1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2016, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Aspects; use Aspects;
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Contracts; use Contracts;
30 with Debug; use Debug;
31 with Elists; use Elists;
32 with Einfo; use Einfo;
33 with Errout; use Errout;
34 with Eval_Fat; use Eval_Fat;
35 with Exp_Ch3; use Exp_Ch3;
36 with Exp_Ch9; use Exp_Ch9;
37 with Exp_Disp; use Exp_Disp;
38 with Exp_Dist; use Exp_Dist;
39 with Exp_Tss; use Exp_Tss;
40 with Exp_Util; use Exp_Util;
41 with Fname; use Fname;
42 with Freeze; use Freeze;
43 with Ghost; use Ghost;
44 with Itypes; use Itypes;
45 with Layout; use Layout;
47 with Lib.Xref; use Lib.Xref;
48 with Namet; use Namet;
49 with Nmake; use Nmake;
51 with Restrict; use Restrict;
52 with Rident; use Rident;
53 with Rtsfind; use Rtsfind;
55 with Sem_Aux; use Sem_Aux;
56 with Sem_Case; use Sem_Case;
57 with Sem_Cat; use Sem_Cat;
58 with Sem_Ch6; use Sem_Ch6;
59 with Sem_Ch7; use Sem_Ch7;
60 with Sem_Ch8; use Sem_Ch8;
61 with Sem_Ch13; use Sem_Ch13;
62 with Sem_Dim; use Sem_Dim;
63 with Sem_Disp; use Sem_Disp;
64 with Sem_Dist; use Sem_Dist;
65 with Sem_Elim; use Sem_Elim;
66 with Sem_Eval; use Sem_Eval;
67 with Sem_Mech; use Sem_Mech;
68 with Sem_Res; use Sem_Res;
69 with Sem_Smem; use Sem_Smem;
70 with Sem_Type; use Sem_Type;
71 with Sem_Util; use Sem_Util;
72 with Sem_Warn; use Sem_Warn;
73 with Stand; use Stand;
74 with Sinfo; use Sinfo;
75 with Sinput; use Sinput;
76 with Snames; use Snames;
77 with Targparm; use Targparm;
78 with Tbuild; use Tbuild;
79 with Ttypes; use Ttypes;
80 with Uintp; use Uintp;
81 with Urealp; use Urealp;
83 package body Sem_Ch3 is
85 -----------------------
86 -- Local Subprograms --
87 -----------------------
89 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id);
90 -- Ada 2005 (AI-251): Add the tag components corresponding to all the
91 -- abstract interface types implemented by a record type or a derived
94 procedure Build_Derived_Type
96 Parent_Type : Entity_Id;
97 Derived_Type : Entity_Id;
98 Is_Completion : Boolean;
99 Derive_Subps : Boolean := True);
100 -- Create and decorate a Derived_Type given the Parent_Type entity. N is
101 -- the N_Full_Type_Declaration node containing the derived type definition.
102 -- Parent_Type is the entity for the parent type in the derived type
103 -- definition and Derived_Type the actual derived type. Is_Completion must
104 -- be set to False if Derived_Type is the N_Defining_Identifier node in N
105 -- (i.e. Derived_Type = Defining_Identifier (N)). In this case N is not the
106 -- completion of a private type declaration. If Is_Completion is set to
107 -- True, N is the completion of a private type declaration and Derived_Type
108 -- is different from the defining identifier inside N (i.e. Derived_Type /=
109 -- Defining_Identifier (N)). Derive_Subps indicates whether the parent
110 -- subprograms should be derived. The only case where this parameter is
111 -- False is when Build_Derived_Type is recursively called to process an
112 -- implicit derived full type for a type derived from a private type (in
113 -- that case the subprograms must only be derived for the private view of
116 -- ??? These flags need a bit of re-examination and re-documentation:
117 -- ??? are they both necessary (both seem related to the recursion)?
119 procedure Build_Derived_Access_Type
121 Parent_Type : Entity_Id;
122 Derived_Type : Entity_Id);
123 -- Subsidiary procedure to Build_Derived_Type. For a derived access type,
124 -- create an implicit base if the parent type is constrained or if the
125 -- subtype indication has a constraint.
127 procedure Build_Derived_Array_Type
129 Parent_Type : Entity_Id;
130 Derived_Type : Entity_Id);
131 -- Subsidiary procedure to Build_Derived_Type. For a derived array type,
132 -- create an implicit base if the parent type is constrained or if the
133 -- subtype indication has a constraint.
135 procedure Build_Derived_Concurrent_Type
137 Parent_Type : Entity_Id;
138 Derived_Type : Entity_Id);
139 -- Subsidiary procedure to Build_Derived_Type. For a derived task or
140 -- protected type, inherit entries and protected subprograms, check
141 -- legality of discriminant constraints if any.
143 procedure Build_Derived_Enumeration_Type
145 Parent_Type : Entity_Id;
146 Derived_Type : Entity_Id);
147 -- Subsidiary procedure to Build_Derived_Type. For a derived enumeration
148 -- type, we must create a new list of literals. Types derived from
149 -- Character and [Wide_]Wide_Character are special-cased.
151 procedure Build_Derived_Numeric_Type
153 Parent_Type : Entity_Id;
154 Derived_Type : Entity_Id);
155 -- Subsidiary procedure to Build_Derived_Type. For numeric types, create
156 -- an anonymous base type, and propagate constraint to subtype if needed.
158 procedure Build_Derived_Private_Type
160 Parent_Type : Entity_Id;
161 Derived_Type : Entity_Id;
162 Is_Completion : Boolean;
163 Derive_Subps : Boolean := True);
164 -- Subsidiary procedure to Build_Derived_Type. This procedure is complex
165 -- because the parent may or may not have a completion, and the derivation
166 -- may itself be a completion.
168 procedure Build_Derived_Record_Type
170 Parent_Type : Entity_Id;
171 Derived_Type : Entity_Id;
172 Derive_Subps : Boolean := True);
173 -- Subsidiary procedure used for tagged and untagged record types
174 -- by Build_Derived_Type and Analyze_Private_Extension_Declaration.
175 -- All parameters are as in Build_Derived_Type except that N, in
176 -- addition to being an N_Full_Type_Declaration node, can also be an
177 -- N_Private_Extension_Declaration node. See the definition of this routine
178 -- for much more info. Derive_Subps indicates whether subprograms should be
179 -- derived from the parent type. The only case where Derive_Subps is False
180 -- is for an implicit derived full type for a type derived from a private
181 -- type (see Build_Derived_Type).
183 procedure Build_Discriminal (Discrim : Entity_Id);
184 -- Create the discriminal corresponding to discriminant Discrim, that is
185 -- the parameter corresponding to Discrim to be used in initialization
186 -- procedures for the type where Discrim is a discriminant. Discriminals
187 -- are not used during semantic analysis, and are not fully defined
188 -- entities until expansion. Thus they are not given a scope until
189 -- initialization procedures are built.
191 function Build_Discriminant_Constraints
194 Derived_Def : Boolean := False) return Elist_Id;
195 -- Validate discriminant constraints and return the list of the constraints
196 -- in order of discriminant declarations, where T is the discriminated
197 -- unconstrained type. Def is the N_Subtype_Indication node where the
198 -- discriminants constraints for T are specified. Derived_Def is True
199 -- when building the discriminant constraints in a derived type definition
200 -- of the form "type D (...) is new T (xxx)". In this case T is the parent
201 -- type and Def is the constraint "(xxx)" on T and this routine sets the
202 -- Corresponding_Discriminant field of the discriminants in the derived
203 -- type D to point to the corresponding discriminants in the parent type T.
205 procedure Build_Discriminated_Subtype
209 Related_Nod : Node_Id;
210 For_Access : Boolean := False);
211 -- Subsidiary procedure to Constrain_Discriminated_Type and to
212 -- Process_Incomplete_Dependents. Given
214 -- T (a possibly discriminated base type)
215 -- Def_Id (a very partially built subtype for T),
217 -- the call completes Def_Id to be the appropriate E_*_Subtype.
219 -- The Elist is the list of discriminant constraints if any (it is set
220 -- to No_Elist if T is not a discriminated type, and to an empty list if
221 -- T has discriminants but there are no discriminant constraints). The
222 -- Related_Nod is the same as Decl_Node in Create_Constrained_Components.
223 -- The For_Access says whether or not this subtype is really constraining
224 -- an access type. That is its sole purpose is the designated type of an
225 -- access type -- in which case a Private_Subtype Is_For_Access_Subtype
226 -- is built to avoid freezing T when the access subtype is frozen.
228 function Build_Scalar_Bound
231 Der_T : Entity_Id) return Node_Id;
232 -- The bounds of a derived scalar type are conversions of the bounds of
233 -- the parent type. Optimize the representation if the bounds are literals.
234 -- Needs a more complete spec--what are the parameters exactly, and what
235 -- exactly is the returned value, and how is Bound affected???
237 procedure Build_Underlying_Full_View
241 -- If the completion of a private type is itself derived from a private
242 -- type, or if the full view of a private subtype is itself private, the
243 -- back-end has no way to compute the actual size of this type. We build
244 -- an internal subtype declaration of the proper parent type to convey
245 -- this information. This extra mechanism is needed because a full
246 -- view cannot itself have a full view (it would get clobbered during
249 procedure Check_Access_Discriminant_Requires_Limited
252 -- Check the restriction that the type to which an access discriminant
253 -- belongs must be a concurrent type or a descendant of a type with
254 -- the reserved word 'limited' in its declaration.
256 procedure Check_Anonymous_Access_Components
260 Comp_List : Node_Id);
261 -- Ada 2005 AI-382: an access component in a record definition can refer to
262 -- the enclosing record, in which case it denotes the type itself, and not
263 -- the current instance of the type. We create an anonymous access type for
264 -- the component, and flag it as an access to a component, so accessibility
265 -- checks are properly performed on it. The declaration of the access type
266 -- is placed ahead of that of the record to prevent order-of-elaboration
267 -- circularity issues in Gigi. We create an incomplete type for the record
268 -- declaration, which is the designated type of the anonymous access.
270 procedure Check_Delta_Expression (E : Node_Id);
271 -- Check that the expression represented by E is suitable for use as a
272 -- delta expression, i.e. it is of real type and is static.
274 procedure Check_Digits_Expression (E : Node_Id);
275 -- Check that the expression represented by E is suitable for use as a
276 -- digits expression, i.e. it is of integer type, positive and static.
278 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id);
279 -- Validate the initialization of an object declaration. T is the required
280 -- type, and Exp is the initialization expression.
282 procedure Check_Interfaces (N : Node_Id; Def : Node_Id);
283 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
285 procedure Check_Or_Process_Discriminants
288 Prev : Entity_Id := Empty);
289 -- If N is the full declaration of the completion T of an incomplete or
290 -- private type, check its discriminants (which are already known to be
291 -- conformant with those of the partial view, see Find_Type_Name),
292 -- otherwise process them. Prev is the entity of the partial declaration,
295 procedure Check_Real_Bound (Bound : Node_Id);
296 -- Check given bound for being of real type and static. If not, post an
297 -- appropriate message, and rewrite the bound with the real literal zero.
299 procedure Constant_Redeclaration
303 -- Various checks on legality of full declaration of deferred constant.
304 -- Id is the entity for the redeclaration, N is the N_Object_Declaration,
305 -- node. The caller has not yet set any attributes of this entity.
307 function Contain_Interface
309 Ifaces : Elist_Id) return Boolean;
310 -- Ada 2005: Determine whether Iface is present in the list Ifaces
312 procedure Convert_Scalar_Bounds
314 Parent_Type : Entity_Id;
315 Derived_Type : Entity_Id;
317 -- For derived scalar types, convert the bounds in the type definition to
318 -- the derived type, and complete their analysis. Given a constraint of the
319 -- form ".. new T range Lo .. Hi", Lo and Hi are analyzed and resolved with
320 -- T'Base, the parent_type. The bounds of the derived type (the anonymous
321 -- base) are copies of Lo and Hi. Finally, the bounds of the derived
322 -- subtype are conversions of those bounds to the derived_type, so that
323 -- their typing is consistent.
325 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id);
326 -- Copies attributes from array base type T2 to array base type T1. Copies
327 -- only attributes that apply to base types, but not subtypes.
329 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id);
330 -- Copies attributes from array subtype T2 to array subtype T1. Copies
331 -- attributes that apply to both subtypes and base types.
333 procedure Create_Constrained_Components
337 Constraints : Elist_Id);
338 -- Build the list of entities for a constrained discriminated record
339 -- subtype. If a component depends on a discriminant, replace its subtype
340 -- using the discriminant values in the discriminant constraint. Subt
341 -- is the defining identifier for the subtype whose list of constrained
342 -- entities we will create. Decl_Node is the type declaration node where
343 -- we will attach all the itypes created. Typ is the base discriminated
344 -- type for the subtype Subt. Constraints is the list of discriminant
345 -- constraints for Typ.
347 function Constrain_Component_Type
349 Constrained_Typ : Entity_Id;
350 Related_Node : Node_Id;
352 Constraints : Elist_Id) return Entity_Id;
353 -- Given a discriminated base type Typ, a list of discriminant constraints,
354 -- Constraints, for Typ and a component Comp of Typ, create and return the
355 -- type corresponding to Etype (Comp) where all discriminant references
356 -- are replaced with the corresponding constraint. If Etype (Comp) contains
357 -- no discriminant references then it is returned as-is. Constrained_Typ
358 -- is the final constrained subtype to which the constrained component
359 -- belongs. Related_Node is the node where we attach all created itypes.
361 procedure Constrain_Access
362 (Def_Id : in out Entity_Id;
364 Related_Nod : Node_Id);
365 -- Apply a list of constraints to an access type. If Def_Id is empty, it is
366 -- an anonymous type created for a subtype indication. In that case it is
367 -- created in the procedure and attached to Related_Nod.
369 procedure Constrain_Array
370 (Def_Id : in out Entity_Id;
372 Related_Nod : Node_Id;
373 Related_Id : Entity_Id;
375 -- Apply a list of index constraints to an unconstrained array type. The
376 -- first parameter is the entity for the resulting subtype. A value of
377 -- Empty for Def_Id indicates that an implicit type must be created, but
378 -- creation is delayed (and must be done by this procedure) because other
379 -- subsidiary implicit types must be created first (which is why Def_Id
380 -- is an in/out parameter). The second parameter is a subtype indication
381 -- node for the constrained array to be created (e.g. something of the
382 -- form string (1 .. 10)). Related_Nod gives the place where this type
383 -- has to be inserted in the tree. The Related_Id and Suffix parameters
384 -- are used to build the associated Implicit type name.
386 procedure Constrain_Concurrent
387 (Def_Id : in out Entity_Id;
389 Related_Nod : Node_Id;
390 Related_Id : Entity_Id;
392 -- Apply list of discriminant constraints to an unconstrained concurrent
395 -- SI is the N_Subtype_Indication node containing the constraint and
396 -- the unconstrained type to constrain.
398 -- Def_Id is the entity for the resulting constrained subtype. A value
399 -- of Empty for Def_Id indicates that an implicit type must be created,
400 -- but creation is delayed (and must be done by this procedure) because
401 -- other subsidiary implicit types must be created first (which is why
402 -- Def_Id is an in/out parameter).
404 -- Related_Nod gives the place where this type has to be inserted
407 -- The last two arguments are used to create its external name if needed.
409 function Constrain_Corresponding_Record
410 (Prot_Subt : Entity_Id;
411 Corr_Rec : Entity_Id;
412 Related_Nod : Node_Id) return Entity_Id;
413 -- When constraining a protected type or task type with discriminants,
414 -- constrain the corresponding record with the same discriminant values.
416 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id);
417 -- Constrain a decimal fixed point type with a digits constraint and/or a
418 -- range constraint, and build E_Decimal_Fixed_Point_Subtype entity.
420 procedure Constrain_Discriminated_Type
423 Related_Nod : Node_Id;
424 For_Access : Boolean := False);
425 -- Process discriminant constraints of composite type. Verify that values
426 -- have been provided for all discriminants, that the original type is
427 -- unconstrained, and that the types of the supplied expressions match
428 -- the discriminant types. The first three parameters are like in routine
429 -- Constrain_Concurrent. See Build_Discriminated_Subtype for an explanation
432 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id);
433 -- Constrain an enumeration type with a range constraint. This is identical
434 -- to Constrain_Integer, but for the Ekind of the resulting subtype.
436 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id);
437 -- Constrain a floating point type with either a digits constraint
438 -- and/or a range constraint, building a E_Floating_Point_Subtype.
440 procedure Constrain_Index
443 Related_Nod : Node_Id;
444 Related_Id : Entity_Id;
447 -- Process an index constraint S in a constrained array declaration. The
448 -- constraint can be a subtype name, or a range with or without an explicit
449 -- subtype mark. The index is the corresponding index of the unconstrained
450 -- array. The Related_Id and Suffix parameters are used to build the
451 -- associated Implicit type name.
453 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id);
454 -- Build subtype of a signed or modular integer type
456 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id);
457 -- Constrain an ordinary fixed point type with a range constraint, and
458 -- build an E_Ordinary_Fixed_Point_Subtype entity.
460 procedure Copy_And_Swap (Priv, Full : Entity_Id);
461 -- Copy the Priv entity into the entity of its full declaration then swap
462 -- the two entities in such a manner that the former private type is now
463 -- seen as a full type.
465 procedure Decimal_Fixed_Point_Type_Declaration
468 -- Create a new decimal fixed point type, and apply the constraint to
469 -- obtain a subtype of this new type.
471 procedure Complete_Private_Subtype
474 Full_Base : Entity_Id;
475 Related_Nod : Node_Id);
476 -- Complete the implicit full view of a private subtype by setting the
477 -- appropriate semantic fields. If the full view of the parent is a record
478 -- type, build constrained components of subtype.
480 procedure Derive_Progenitor_Subprograms
481 (Parent_Type : Entity_Id;
482 Tagged_Type : Entity_Id);
483 -- Ada 2005 (AI-251): To complete type derivation, collect the primitive
484 -- operations of progenitors of Tagged_Type, and replace the subsidiary
485 -- subtypes with Tagged_Type, to build the specs of the inherited interface
486 -- primitives. The derived primitives are aliased to those of the
487 -- interface. This routine takes care also of transferring to the full view
488 -- subprograms associated with the partial view of Tagged_Type that cover
489 -- interface primitives.
491 procedure Derived_Standard_Character
493 Parent_Type : Entity_Id;
494 Derived_Type : Entity_Id);
495 -- Subsidiary procedure to Build_Derived_Enumeration_Type which handles
496 -- derivations from types Standard.Character and Standard.Wide_Character.
498 procedure Derived_Type_Declaration
501 Is_Completion : Boolean);
502 -- Process a derived type declaration. Build_Derived_Type is invoked
503 -- to process the actual derived type definition. Parameters N and
504 -- Is_Completion have the same meaning as in Build_Derived_Type.
505 -- T is the N_Defining_Identifier for the entity defined in the
506 -- N_Full_Type_Declaration node N, that is T is the derived type.
508 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id);
509 -- Insert each literal in symbol table, as an overloadable identifier. Each
510 -- enumeration type is mapped into a sequence of integers, and each literal
511 -- is defined as a constant with integer value. If any of the literals are
512 -- character literals, the type is a character type, which means that
513 -- strings are legal aggregates for arrays of components of the type.
515 function Expand_To_Stored_Constraint
517 Constraint : Elist_Id) return Elist_Id;
518 -- Given a constraint (i.e. a list of expressions) on the discriminants of
519 -- Typ, expand it into a constraint on the stored discriminants and return
520 -- the new list of expressions constraining the stored discriminants.
522 function Find_Type_Of_Object
524 Related_Nod : Node_Id) return Entity_Id;
525 -- Get type entity for object referenced by Obj_Def, attaching the implicit
526 -- types generated to Related_Nod.
528 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id);
529 -- Create a new float and apply the constraint to obtain subtype of it
531 function Has_Range_Constraint (N : Node_Id) return Boolean;
532 -- Given an N_Subtype_Indication node N, return True if a range constraint
533 -- is present, either directly, or as part of a digits or delta constraint.
534 -- In addition, a digits constraint in the decimal case returns True, since
535 -- it establishes a default range if no explicit range is present.
537 function Inherit_Components
539 Parent_Base : Entity_Id;
540 Derived_Base : Entity_Id;
542 Inherit_Discr : Boolean;
543 Discs : Elist_Id) return Elist_Id;
544 -- Called from Build_Derived_Record_Type to inherit the components of
545 -- Parent_Base (a base type) into the Derived_Base (the derived base type).
546 -- For more information on derived types and component inheritance please
547 -- consult the comment above the body of Build_Derived_Record_Type.
549 -- N is the original derived type declaration
551 -- Is_Tagged is set if we are dealing with tagged types
553 -- If Inherit_Discr is set, Derived_Base inherits its discriminants from
554 -- Parent_Base, otherwise no discriminants are inherited.
556 -- Discs gives the list of constraints that apply to Parent_Base in the
557 -- derived type declaration. If Discs is set to No_Elist, then we have
558 -- the following situation:
560 -- type Parent (D1..Dn : ..) is [tagged] record ...;
561 -- type Derived is new Parent [with ...];
563 -- which gets treated as
565 -- type Derived (D1..Dn : ..) is new Parent (D1,..,Dn) [with ...];
567 -- For untagged types the returned value is an association list. The list
568 -- starts from the association (Parent_Base => Derived_Base), and then it
569 -- contains a sequence of the associations of the form
571 -- (Old_Component => New_Component),
573 -- where Old_Component is the Entity_Id of a component in Parent_Base and
574 -- New_Component is the Entity_Id of the corresponding component in
575 -- Derived_Base. For untagged records, this association list is needed when
576 -- copying the record declaration for the derived base. In the tagged case
577 -- the value returned is irrelevant.
579 procedure Inherit_Predicate_Flags (Subt, Par : Entity_Id);
580 -- Propagate static and dynamic predicate flags from a parent to the
581 -- subtype in a subtype declaration with and without constraints.
583 function Is_EVF_Procedure (Subp : Entity_Id) return Boolean;
584 -- Subsidiary to Check_Abstract_Overriding and Derive_Subprogram.
585 -- Determine whether subprogram Subp is a procedure subject to pragma
586 -- Extensions_Visible with value False and has at least one controlling
587 -- parameter of mode OUT.
589 function Is_Valid_Constraint_Kind
591 Constraint_Kind : Node_Kind) return Boolean;
592 -- Returns True if it is legal to apply the given kind of constraint to the
593 -- given kind of type (index constraint to an array type, for example).
595 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id);
596 -- Create new modular type. Verify that modulus is in bounds
598 procedure New_Concatenation_Op (Typ : Entity_Id);
599 -- Create an abbreviated declaration for an operator in order to
600 -- materialize concatenation on array types.
602 procedure Ordinary_Fixed_Point_Type_Declaration
605 -- Create a new ordinary fixed point type, and apply the constraint to
606 -- obtain subtype of it.
608 procedure Prepare_Private_Subtype_Completion
610 Related_Nod : Node_Id);
611 -- Id is a subtype of some private type. Creates the full declaration
612 -- associated with Id whenever possible, i.e. when the full declaration
613 -- of the base type is already known. Records each subtype into
614 -- Private_Dependents of the base type.
616 procedure Process_Incomplete_Dependents
620 -- Process all entities that depend on an incomplete type. There include
621 -- subtypes, subprogram types that mention the incomplete type in their
622 -- profiles, and subprogram with access parameters that designate the
625 -- Inc_T is the defining identifier of an incomplete type declaration, its
626 -- Ekind is E_Incomplete_Type.
628 -- N is the corresponding N_Full_Type_Declaration for Inc_T.
630 -- Full_T is N's defining identifier.
632 -- Subtypes of incomplete types with discriminants are completed when the
633 -- parent type is. This is simpler than private subtypes, because they can
634 -- only appear in the same scope, and there is no need to exchange views.
635 -- Similarly, access_to_subprogram types may have a parameter or a return
636 -- type that is an incomplete type, and that must be replaced with the
639 -- If the full type is tagged, subprogram with access parameters that
640 -- designated the incomplete may be primitive operations of the full type,
641 -- and have to be processed accordingly.
643 procedure Process_Real_Range_Specification (Def : Node_Id);
644 -- Given the type definition for a real type, this procedure processes and
645 -- checks the real range specification of this type definition if one is
646 -- present. If errors are found, error messages are posted, and the
647 -- Real_Range_Specification of Def is reset to Empty.
649 procedure Propagate_Default_Init_Cond_Attributes
650 (From_Typ : Entity_Id;
652 Parent_To_Derivation : Boolean := False;
653 Private_To_Full_View : Boolean := False);
654 -- Subsidiary to routines Build_Derived_Type and Process_Full_View. Inherit
655 -- all attributes related to pragma Default_Initial_Condition from From_Typ
656 -- to To_Typ. Flag Parent_To_Derivation should be set when the context is
657 -- the creation of a derived type. Flag Private_To_Full_View should be set
658 -- when processing both views of a private type.
660 procedure Record_Type_Declaration
664 -- Process a record type declaration (for both untagged and tagged
665 -- records). Parameters T and N are exactly like in procedure
666 -- Derived_Type_Declaration, except that no flag Is_Completion is needed
667 -- for this routine. If this is the completion of an incomplete type
668 -- declaration, Prev is the entity of the incomplete declaration, used for
669 -- cross-referencing. Otherwise Prev = T.
671 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id);
672 -- This routine is used to process the actual record type definition (both
673 -- for untagged and tagged records). Def is a record type definition node.
674 -- This procedure analyzes the components in this record type definition.
675 -- Prev_T is the entity for the enclosing record type. It is provided so
676 -- that its Has_Task flag can be set if any of the component have Has_Task
677 -- set. If the declaration is the completion of an incomplete type
678 -- declaration, Prev_T is the original incomplete type, whose full view is
681 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id);
682 -- Subsidiary to Build_Derived_Record_Type. For untagged records, we
683 -- build a copy of the declaration tree of the parent, and we create
684 -- independently the list of components for the derived type. Semantic
685 -- information uses the component entities, but record representation
686 -- clauses are validated on the declaration tree. This procedure replaces
687 -- discriminants and components in the declaration with those that have
688 -- been created by Inherit_Components.
690 procedure Set_Fixed_Range
695 -- Build a range node with the given bounds and set it as the Scalar_Range
696 -- of the given fixed-point type entity. Loc is the source location used
697 -- for the constructed range. See body for further details.
699 procedure Set_Scalar_Range_For_Subtype
703 -- This routine is used to set the scalar range field for a subtype given
704 -- Def_Id, the entity for the subtype, and R, the range expression for the
705 -- scalar range. Subt provides the parent subtype to be used to analyze,
706 -- resolve, and check the given range.
708 procedure Set_Default_SSO (T : Entity_Id);
709 -- T is the entity for an array or record being declared. This procedure
710 -- sets the flags SSO_Set_Low_By_Default/SSO_Set_High_By_Default according
711 -- to the setting of Opt.Default_SSO.
713 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id);
714 -- Create a new signed integer entity, and apply the constraint to obtain
715 -- the required first named subtype of this type.
717 procedure Set_Stored_Constraint_From_Discriminant_Constraint
719 -- E is some record type. This routine computes E's Stored_Constraint
720 -- from its Discriminant_Constraint.
722 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id);
723 -- Check that an entity in a list of progenitors is an interface,
724 -- emit error otherwise.
726 -----------------------
727 -- Access_Definition --
728 -----------------------
730 function Access_Definition
731 (Related_Nod : Node_Id;
732 N : Node_Id) return Entity_Id
734 Anon_Type : Entity_Id;
735 Anon_Scope : Entity_Id;
736 Desig_Type : Entity_Id;
737 Enclosing_Prot_Type : Entity_Id := Empty;
740 Check_SPARK_05_Restriction ("access type is not allowed", N);
742 if Is_Entry (Current_Scope)
743 and then Is_Task_Type (Etype (Scope (Current_Scope)))
745 Error_Msg_N ("task entries cannot have access parameters", N);
749 -- Ada 2005: For an object declaration the corresponding anonymous
750 -- type is declared in the current scope.
752 -- If the access definition is the return type of another access to
753 -- function, scope is the current one, because it is the one of the
754 -- current type declaration, except for the pathological case below.
756 if Nkind_In (Related_Nod, N_Object_Declaration,
757 N_Access_Function_Definition)
759 Anon_Scope := Current_Scope;
761 -- A pathological case: function returning access functions that
762 -- return access functions, etc. Each anonymous access type created
763 -- is in the enclosing scope of the outermost function.
770 while Nkind_In (Par, N_Access_Function_Definition,
776 if Nkind (Par) = N_Function_Specification then
777 Anon_Scope := Scope (Defining_Entity (Par));
781 -- For the anonymous function result case, retrieve the scope of the
782 -- function specification's associated entity rather than using the
783 -- current scope. The current scope will be the function itself if the
784 -- formal part is currently being analyzed, but will be the parent scope
785 -- in the case of a parameterless function, and we always want to use
786 -- the function's parent scope. Finally, if the function is a child
787 -- unit, we must traverse the tree to retrieve the proper entity.
789 elsif Nkind (Related_Nod) = N_Function_Specification
790 and then Nkind (Parent (N)) /= N_Parameter_Specification
792 -- If the current scope is a protected type, the anonymous access
793 -- is associated with one of the protected operations, and must
794 -- be available in the scope that encloses the protected declaration.
795 -- Otherwise the type is in the scope enclosing the subprogram.
797 -- If the function has formals, The return type of a subprogram
798 -- declaration is analyzed in the scope of the subprogram (see
799 -- Process_Formals) and thus the protected type, if present, is
800 -- the scope of the current function scope.
802 if Ekind (Current_Scope) = E_Protected_Type then
803 Enclosing_Prot_Type := Current_Scope;
805 elsif Ekind (Current_Scope) = E_Function
806 and then Ekind (Scope (Current_Scope)) = E_Protected_Type
808 Enclosing_Prot_Type := Scope (Current_Scope);
811 if Present (Enclosing_Prot_Type) then
812 Anon_Scope := Scope (Enclosing_Prot_Type);
815 Anon_Scope := Scope (Defining_Entity (Related_Nod));
818 -- For an access type definition, if the current scope is a child
819 -- unit it is the scope of the type.
821 elsif Is_Compilation_Unit (Current_Scope) then
822 Anon_Scope := Current_Scope;
824 -- For access formals, access components, and access discriminants, the
825 -- scope is that of the enclosing declaration,
828 Anon_Scope := Scope (Current_Scope);
833 (E_Anonymous_Access_Type, Related_Nod, Scope_Id => Anon_Scope);
836 and then Ada_Version >= Ada_2005
838 Error_Msg_N ("ALL is not permitted for anonymous access types", N);
841 -- Ada 2005 (AI-254): In case of anonymous access to subprograms call
842 -- the corresponding semantic routine
844 if Present (Access_To_Subprogram_Definition (N)) then
846 -- Compiler runtime units are compiled in Ada 2005 mode when building
847 -- the runtime library but must also be compilable in Ada 95 mode
848 -- (when bootstrapping the compiler).
850 Check_Compiler_Unit ("anonymous access to subprogram", N);
852 Access_Subprogram_Declaration
853 (T_Name => Anon_Type,
854 T_Def => Access_To_Subprogram_Definition (N));
856 if Ekind (Anon_Type) = E_Access_Protected_Subprogram_Type then
858 (Anon_Type, E_Anonymous_Access_Protected_Subprogram_Type);
860 Set_Ekind (Anon_Type, E_Anonymous_Access_Subprogram_Type);
863 Set_Can_Use_Internal_Rep
864 (Anon_Type, not Always_Compatible_Rep_On_Target);
866 -- If the anonymous access is associated with a protected operation,
867 -- create a reference to it after the enclosing protected definition
868 -- because the itype will be used in the subsequent bodies.
870 -- If the anonymous access itself is protected, a full type
871 -- declaratiton will be created for it, so that the equivalent
872 -- record type can be constructed. For further details, see
873 -- Replace_Anonymous_Access_To_Protected-Subprogram.
875 if Ekind (Current_Scope) = E_Protected_Type
876 and then not Protected_Present (Access_To_Subprogram_Definition (N))
878 Build_Itype_Reference (Anon_Type, Parent (Current_Scope));
884 Find_Type (Subtype_Mark (N));
885 Desig_Type := Entity (Subtype_Mark (N));
887 Set_Directly_Designated_Type (Anon_Type, Desig_Type);
888 Set_Etype (Anon_Type, Anon_Type);
890 -- Make sure the anonymous access type has size and alignment fields
891 -- set, as required by gigi. This is necessary in the case of the
892 -- Task_Body_Procedure.
894 if not Has_Private_Component (Desig_Type) then
895 Layout_Type (Anon_Type);
898 -- Ada 2005 (AI-231): Ada 2005 semantics for anonymous access differs
899 -- from Ada 95 semantics. In Ada 2005, anonymous access must specify if
900 -- the null value is allowed. In Ada 95 the null value is never allowed.
902 if Ada_Version >= Ada_2005 then
903 Set_Can_Never_Be_Null (Anon_Type, Null_Exclusion_Present (N));
905 Set_Can_Never_Be_Null (Anon_Type, True);
908 -- The anonymous access type is as public as the discriminated type or
909 -- subprogram that defines it. It is imported (for back-end purposes)
910 -- if the designated type is.
912 Set_Is_Public (Anon_Type, Is_Public (Scope (Anon_Type)));
914 -- Ada 2005 (AI-231): Propagate the access-constant attribute
916 Set_Is_Access_Constant (Anon_Type, Constant_Present (N));
918 -- The context is either a subprogram declaration, object declaration,
919 -- or an access discriminant, in a private or a full type declaration.
920 -- In the case of a subprogram, if the designated type is incomplete,
921 -- the operation will be a primitive operation of the full type, to be
922 -- updated subsequently. If the type is imported through a limited_with
923 -- clause, the subprogram is not a primitive operation of the type
924 -- (which is declared elsewhere in some other scope).
926 if Ekind (Desig_Type) = E_Incomplete_Type
927 and then not From_Limited_With (Desig_Type)
928 and then Is_Overloadable (Current_Scope)
930 Append_Elmt (Current_Scope, Private_Dependents (Desig_Type));
931 Set_Has_Delayed_Freeze (Current_Scope);
934 -- Ada 2005: If the designated type is an interface that may contain
935 -- tasks, create a Master entity for the declaration. This must be done
936 -- before expansion of the full declaration, because the declaration may
937 -- include an expression that is an allocator, whose expansion needs the
938 -- proper Master for the created tasks.
940 if Nkind (Related_Nod) = N_Object_Declaration and then Expander_Active
942 if Is_Interface (Desig_Type) and then Is_Limited_Record (Desig_Type)
944 Build_Class_Wide_Master (Anon_Type);
946 -- Similarly, if the type is an anonymous access that designates
947 -- tasks, create a master entity for it in the current context.
949 elsif Has_Task (Desig_Type) and then Comes_From_Source (Related_Nod)
951 Build_Master_Entity (Defining_Identifier (Related_Nod));
952 Build_Master_Renaming (Anon_Type);
956 -- For a private component of a protected type, it is imperative that
957 -- the back-end elaborate the type immediately after the protected
958 -- declaration, because this type will be used in the declarations
959 -- created for the component within each protected body, so we must
960 -- create an itype reference for it now.
962 if Nkind (Parent (Related_Nod)) = N_Protected_Definition then
963 Build_Itype_Reference (Anon_Type, Parent (Parent (Related_Nod)));
965 -- Similarly, if the access definition is the return result of a
966 -- function, create an itype reference for it because it will be used
967 -- within the function body. For a regular function that is not a
968 -- compilation unit, insert reference after the declaration. For a
969 -- protected operation, insert it after the enclosing protected type
970 -- declaration. In either case, do not create a reference for a type
971 -- obtained through a limited_with clause, because this would introduce
972 -- semantic dependencies.
974 -- Similarly, do not create a reference if the designated type is a
975 -- generic formal, because no use of it will reach the backend.
977 elsif Nkind (Related_Nod) = N_Function_Specification
978 and then not From_Limited_With (Desig_Type)
979 and then not Is_Generic_Type (Desig_Type)
981 if Present (Enclosing_Prot_Type) then
982 Build_Itype_Reference (Anon_Type, Parent (Enclosing_Prot_Type));
984 elsif Is_List_Member (Parent (Related_Nod))
985 and then Nkind (Parent (N)) /= N_Parameter_Specification
987 Build_Itype_Reference (Anon_Type, Parent (Related_Nod));
990 -- Finally, create an itype reference for an object declaration of an
991 -- anonymous access type. This is strictly necessary only for deferred
992 -- constants, but in any case will avoid out-of-scope problems in the
995 elsif Nkind (Related_Nod) = N_Object_Declaration then
996 Build_Itype_Reference (Anon_Type, Related_Nod);
1000 end Access_Definition;
1002 -----------------------------------
1003 -- Access_Subprogram_Declaration --
1004 -----------------------------------
1006 procedure Access_Subprogram_Declaration
1007 (T_Name : Entity_Id;
1010 procedure Check_For_Premature_Usage (Def : Node_Id);
1011 -- Check that type T_Name is not used, directly or recursively, as a
1012 -- parameter or a return type in Def. Def is either a subtype, an
1013 -- access_definition, or an access_to_subprogram_definition.
1015 -------------------------------
1016 -- Check_For_Premature_Usage --
1017 -------------------------------
1019 procedure Check_For_Premature_Usage (Def : Node_Id) is
1023 -- Check for a subtype mark
1025 if Nkind (Def) in N_Has_Etype then
1026 if Etype (Def) = T_Name then
1028 ("type& cannot be used before end of its declaration", Def);
1031 -- If this is not a subtype, then this is an access_definition
1033 elsif Nkind (Def) = N_Access_Definition then
1034 if Present (Access_To_Subprogram_Definition (Def)) then
1035 Check_For_Premature_Usage
1036 (Access_To_Subprogram_Definition (Def));
1038 Check_For_Premature_Usage (Subtype_Mark (Def));
1041 -- The only cases left are N_Access_Function_Definition and
1042 -- N_Access_Procedure_Definition.
1045 if Present (Parameter_Specifications (Def)) then
1046 Param := First (Parameter_Specifications (Def));
1047 while Present (Param) loop
1048 Check_For_Premature_Usage (Parameter_Type (Param));
1049 Param := Next (Param);
1053 if Nkind (Def) = N_Access_Function_Definition then
1054 Check_For_Premature_Usage (Result_Definition (Def));
1057 end Check_For_Premature_Usage;
1061 Formals : constant List_Id := Parameter_Specifications (T_Def);
1064 Desig_Type : constant Entity_Id :=
1065 Create_Itype (E_Subprogram_Type, Parent (T_Def));
1067 -- Start of processing for Access_Subprogram_Declaration
1070 Check_SPARK_05_Restriction ("access type is not allowed", T_Def);
1072 -- Associate the Itype node with the inner full-type declaration or
1073 -- subprogram spec or entry body. This is required to handle nested
1074 -- anonymous declarations. For example:
1077 -- (X : access procedure
1078 -- (Y : access procedure
1081 D_Ityp := Associated_Node_For_Itype (Desig_Type);
1082 while not (Nkind_In (D_Ityp, N_Full_Type_Declaration,
1083 N_Private_Type_Declaration,
1084 N_Private_Extension_Declaration,
1085 N_Procedure_Specification,
1086 N_Function_Specification,
1090 Nkind_In (D_Ityp, N_Object_Declaration,
1091 N_Object_Renaming_Declaration,
1092 N_Formal_Object_Declaration,
1093 N_Formal_Type_Declaration,
1094 N_Task_Type_Declaration,
1095 N_Protected_Type_Declaration))
1097 D_Ityp := Parent (D_Ityp);
1098 pragma Assert (D_Ityp /= Empty);
1101 Set_Associated_Node_For_Itype (Desig_Type, D_Ityp);
1103 if Nkind_In (D_Ityp, N_Procedure_Specification,
1104 N_Function_Specification)
1106 Set_Scope (Desig_Type, Scope (Defining_Entity (D_Ityp)));
1108 elsif Nkind_In (D_Ityp, N_Full_Type_Declaration,
1109 N_Object_Declaration,
1110 N_Object_Renaming_Declaration,
1111 N_Formal_Type_Declaration)
1113 Set_Scope (Desig_Type, Scope (Defining_Identifier (D_Ityp)));
1116 if Nkind (T_Def) = N_Access_Function_Definition then
1117 if Nkind (Result_Definition (T_Def)) = N_Access_Definition then
1119 Acc : constant Node_Id := Result_Definition (T_Def);
1122 if Present (Access_To_Subprogram_Definition (Acc))
1124 Protected_Present (Access_To_Subprogram_Definition (Acc))
1128 Replace_Anonymous_Access_To_Protected_Subprogram
1134 Access_Definition (T_Def, Result_Definition (T_Def)));
1139 Analyze (Result_Definition (T_Def));
1142 Typ : constant Entity_Id := Entity (Result_Definition (T_Def));
1145 -- If a null exclusion is imposed on the result type, then
1146 -- create a null-excluding itype (an access subtype) and use
1147 -- it as the function's Etype.
1149 if Is_Access_Type (Typ)
1150 and then Null_Exclusion_In_Return_Present (T_Def)
1152 Set_Etype (Desig_Type,
1153 Create_Null_Excluding_Itype
1155 Related_Nod => T_Def,
1156 Scope_Id => Current_Scope));
1159 if From_Limited_With (Typ) then
1161 -- AI05-151: Incomplete types are allowed in all basic
1162 -- declarations, including access to subprograms.
1164 if Ada_Version >= Ada_2012 then
1169 ("illegal use of incomplete type&",
1170 Result_Definition (T_Def), Typ);
1173 elsif Ekind (Current_Scope) = E_Package
1174 and then In_Private_Part (Current_Scope)
1176 if Ekind (Typ) = E_Incomplete_Type then
1177 Append_Elmt (Desig_Type, Private_Dependents (Typ));
1179 elsif Is_Class_Wide_Type (Typ)
1180 and then Ekind (Etype (Typ)) = E_Incomplete_Type
1183 (Desig_Type, Private_Dependents (Etype (Typ)));
1187 Set_Etype (Desig_Type, Typ);
1192 if not (Is_Type (Etype (Desig_Type))) then
1194 ("expect type in function specification",
1195 Result_Definition (T_Def));
1199 Set_Etype (Desig_Type, Standard_Void_Type);
1202 if Present (Formals) then
1203 Push_Scope (Desig_Type);
1205 -- Some special tests here. These special tests can be removed
1206 -- if and when Itypes always have proper parent pointers to their
1209 -- Special test 1) Link defining_identifier of formals. Required by
1210 -- First_Formal to provide its functionality.
1216 F := First (Formals);
1218 -- In ASIS mode, the access_to_subprogram may be analyzed twice,
1219 -- when it is part of an unconstrained type and subtype expansion
1220 -- is disabled. To avoid back-end problems with shared profiles,
1221 -- use previous subprogram type as the designated type, and then
1222 -- remove scope added above.
1224 if ASIS_Mode and then Present (Scope (Defining_Identifier (F)))
1226 Set_Etype (T_Name, T_Name);
1227 Init_Size_Align (T_Name);
1228 Set_Directly_Designated_Type (T_Name,
1229 Scope (Defining_Identifier (F)));
1234 while Present (F) loop
1235 if No (Parent (Defining_Identifier (F))) then
1236 Set_Parent (Defining_Identifier (F), F);
1243 Process_Formals (Formals, Parent (T_Def));
1245 -- Special test 2) End_Scope requires that the parent pointer be set
1246 -- to something reasonable, but Itypes don't have parent pointers. So
1247 -- we set it and then unset it ???
1249 Set_Parent (Desig_Type, T_Name);
1251 Set_Parent (Desig_Type, Empty);
1254 -- Check for premature usage of the type being defined
1256 Check_For_Premature_Usage (T_Def);
1258 -- The return type and/or any parameter type may be incomplete. Mark the
1259 -- subprogram_type as depending on the incomplete type, so that it can
1260 -- be updated when the full type declaration is seen. This only applies
1261 -- to incomplete types declared in some enclosing scope, not to limited
1262 -- views from other packages.
1264 -- Prior to Ada 2012, access to functions can only have in_parameters.
1266 if Present (Formals) then
1267 Formal := First_Formal (Desig_Type);
1268 while Present (Formal) loop
1269 if Ekind (Formal) /= E_In_Parameter
1270 and then Nkind (T_Def) = N_Access_Function_Definition
1271 and then Ada_Version < Ada_2012
1273 Error_Msg_N ("functions can only have IN parameters", Formal);
1276 if Ekind (Etype (Formal)) = E_Incomplete_Type
1277 and then In_Open_Scopes (Scope (Etype (Formal)))
1279 Append_Elmt (Desig_Type, Private_Dependents (Etype (Formal)));
1280 Set_Has_Delayed_Freeze (Desig_Type);
1283 Next_Formal (Formal);
1287 -- Check whether an indirect call without actuals may be possible. This
1288 -- is used when resolving calls whose result is then indexed.
1290 May_Need_Actuals (Desig_Type);
1292 -- If the return type is incomplete, this is legal as long as the type
1293 -- is declared in the current scope and will be completed in it (rather
1294 -- than being part of limited view).
1296 if Ekind (Etype (Desig_Type)) = E_Incomplete_Type
1297 and then not Has_Delayed_Freeze (Desig_Type)
1298 and then In_Open_Scopes (Scope (Etype (Desig_Type)))
1300 Append_Elmt (Desig_Type, Private_Dependents (Etype (Desig_Type)));
1301 Set_Has_Delayed_Freeze (Desig_Type);
1304 Check_Delayed_Subprogram (Desig_Type);
1306 if Protected_Present (T_Def) then
1307 Set_Ekind (T_Name, E_Access_Protected_Subprogram_Type);
1308 Set_Convention (Desig_Type, Convention_Protected);
1310 Set_Ekind (T_Name, E_Access_Subprogram_Type);
1313 Set_Can_Use_Internal_Rep (T_Name, not Always_Compatible_Rep_On_Target);
1315 Set_Etype (T_Name, T_Name);
1316 Init_Size_Align (T_Name);
1317 Set_Directly_Designated_Type (T_Name, Desig_Type);
1319 Generate_Reference_To_Formals (T_Name);
1321 -- Ada 2005 (AI-231): Propagate the null-excluding attribute
1323 Set_Can_Never_Be_Null (T_Name, Null_Exclusion_Present (T_Def));
1325 Check_Restriction (No_Access_Subprograms, T_Def);
1326 end Access_Subprogram_Declaration;
1328 ----------------------------
1329 -- Access_Type_Declaration --
1330 ----------------------------
1332 procedure Access_Type_Declaration (T : Entity_Id; Def : Node_Id) is
1333 P : constant Node_Id := Parent (Def);
1334 S : constant Node_Id := Subtype_Indication (Def);
1336 Full_Desig : Entity_Id;
1339 Check_SPARK_05_Restriction ("access type is not allowed", Def);
1341 -- Check for permissible use of incomplete type
1343 if Nkind (S) /= N_Subtype_Indication then
1346 if Ekind (Root_Type (Entity (S))) = E_Incomplete_Type then
1347 Set_Directly_Designated_Type (T, Entity (S));
1349 -- If the designated type is a limited view, we cannot tell if
1350 -- the full view contains tasks, and there is no way to handle
1351 -- that full view in a client. We create a master entity for the
1352 -- scope, which will be used when a client determines that one
1355 if From_Limited_With (Entity (S))
1356 and then not Is_Class_Wide_Type (Entity (S))
1358 Set_Ekind (T, E_Access_Type);
1359 Build_Master_Entity (T);
1360 Build_Master_Renaming (T);
1364 Set_Directly_Designated_Type (T, Process_Subtype (S, P, T, 'P'));
1367 -- If the access definition is of the form: ACCESS NOT NULL ..
1368 -- the subtype indication must be of an access type. Create
1369 -- a null-excluding subtype of it.
1371 if Null_Excluding_Subtype (Def) then
1372 if not Is_Access_Type (Entity (S)) then
1373 Error_Msg_N ("null exclusion must apply to access type", Def);
1377 Loc : constant Source_Ptr := Sloc (S);
1379 Nam : constant Entity_Id := Make_Temporary (Loc, 'S');
1383 Make_Subtype_Declaration (Loc,
1384 Defining_Identifier => Nam,
1385 Subtype_Indication =>
1386 New_Occurrence_Of (Entity (S), Loc));
1387 Set_Null_Exclusion_Present (Decl);
1388 Insert_Before (Parent (Def), Decl);
1390 Set_Entity (S, Nam);
1396 Set_Directly_Designated_Type (T,
1397 Process_Subtype (S, P, T, 'P'));
1400 if All_Present (Def) or Constant_Present (Def) then
1401 Set_Ekind (T, E_General_Access_Type);
1403 Set_Ekind (T, E_Access_Type);
1406 Full_Desig := Designated_Type (T);
1408 if Base_Type (Full_Desig) = T then
1409 Error_Msg_N ("access type cannot designate itself", S);
1411 -- In Ada 2005, the type may have a limited view through some unit in
1412 -- its own context, allowing the following circularity that cannot be
1413 -- detected earlier.
1415 elsif Is_Class_Wide_Type (Full_Desig) and then Etype (Full_Desig) = T
1418 ("access type cannot designate its own class-wide type", S);
1420 -- Clean up indication of tagged status to prevent cascaded errors
1422 Set_Is_Tagged_Type (T, False);
1427 -- If the type has appeared already in a with_type clause, it is frozen
1428 -- and the pointer size is already set. Else, initialize.
1430 if not From_Limited_With (T) then
1431 Init_Size_Align (T);
1434 -- Note that Has_Task is always false, since the access type itself
1435 -- is not a task type. See Einfo for more description on this point.
1436 -- Exactly the same consideration applies to Has_Controlled_Component
1437 -- and to Has_Protected.
1439 Set_Has_Task (T, False);
1440 Set_Has_Protected (T, False);
1441 Set_Has_Timing_Event (T, False);
1442 Set_Has_Controlled_Component (T, False);
1444 -- Initialize field Finalization_Master explicitly to Empty, to avoid
1445 -- problems where an incomplete view of this entity has been previously
1446 -- established by a limited with and an overlaid version of this field
1447 -- (Stored_Constraint) was initialized for the incomplete view.
1449 -- This reset is performed in most cases except where the access type
1450 -- has been created for the purposes of allocating or deallocating a
1451 -- build-in-place object. Such access types have explicitly set pools
1452 -- and finalization masters.
1454 if No (Associated_Storage_Pool (T)) then
1455 Set_Finalization_Master (T, Empty);
1458 -- Ada 2005 (AI-231): Propagate the null-excluding and access-constant
1461 Set_Can_Never_Be_Null (T, Null_Exclusion_Present (Def));
1462 Set_Is_Access_Constant (T, Constant_Present (Def));
1463 end Access_Type_Declaration;
1465 ----------------------------------
1466 -- Add_Interface_Tag_Components --
1467 ----------------------------------
1469 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id) is
1470 Loc : constant Source_Ptr := Sloc (N);
1474 procedure Add_Tag (Iface : Entity_Id);
1475 -- Add tag for one of the progenitor interfaces
1481 procedure Add_Tag (Iface : Entity_Id) is
1488 pragma Assert (Is_Tagged_Type (Iface) and then Is_Interface (Iface));
1490 -- This is a reasonable place to propagate predicates
1492 if Has_Predicates (Iface) then
1493 Set_Has_Predicates (Typ);
1497 Make_Component_Definition (Loc,
1498 Aliased_Present => True,
1499 Subtype_Indication =>
1500 New_Occurrence_Of (RTE (RE_Interface_Tag), Loc));
1502 Tag := Make_Temporary (Loc, 'V');
1505 Make_Component_Declaration (Loc,
1506 Defining_Identifier => Tag,
1507 Component_Definition => Def);
1509 Analyze_Component_Declaration (Decl);
1511 Set_Analyzed (Decl);
1512 Set_Ekind (Tag, E_Component);
1514 Set_Is_Aliased (Tag);
1515 Set_Related_Type (Tag, Iface);
1516 Init_Component_Location (Tag);
1518 pragma Assert (Is_Frozen (Iface));
1520 Set_DT_Entry_Count (Tag,
1521 DT_Entry_Count (First_Entity (Iface)));
1523 if No (Last_Tag) then
1526 Insert_After (Last_Tag, Decl);
1531 -- If the ancestor has discriminants we need to give special support
1532 -- to store the offset_to_top value of the secondary dispatch tables.
1533 -- For this purpose we add a supplementary component just after the
1534 -- field that contains the tag associated with each secondary DT.
1536 if Typ /= Etype (Typ) and then Has_Discriminants (Etype (Typ)) then
1538 Make_Component_Definition (Loc,
1539 Subtype_Indication =>
1540 New_Occurrence_Of (RTE (RE_Storage_Offset), Loc));
1542 Offset := Make_Temporary (Loc, 'V');
1545 Make_Component_Declaration (Loc,
1546 Defining_Identifier => Offset,
1547 Component_Definition => Def);
1549 Analyze_Component_Declaration (Decl);
1551 Set_Analyzed (Decl);
1552 Set_Ekind (Offset, E_Component);
1553 Set_Is_Aliased (Offset);
1554 Set_Related_Type (Offset, Iface);
1555 Init_Component_Location (Offset);
1556 Insert_After (Last_Tag, Decl);
1567 -- Start of processing for Add_Interface_Tag_Components
1570 if not RTE_Available (RE_Interface_Tag) then
1572 ("(Ada 2005) interface types not supported by this run-time!",
1577 if Ekind (Typ) /= E_Record_Type
1578 or else (Is_Concurrent_Record_Type (Typ)
1579 and then Is_Empty_List (Abstract_Interface_List (Typ)))
1580 or else (not Is_Concurrent_Record_Type (Typ)
1581 and then No (Interfaces (Typ))
1582 and then Is_Empty_Elmt_List (Interfaces (Typ)))
1587 -- Find the current last tag
1589 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1590 Ext := Record_Extension_Part (Type_Definition (N));
1592 pragma Assert (Nkind (Type_Definition (N)) = N_Record_Definition);
1593 Ext := Type_Definition (N);
1598 if not (Present (Component_List (Ext))) then
1599 Set_Null_Present (Ext, False);
1601 Set_Component_List (Ext,
1602 Make_Component_List (Loc,
1603 Component_Items => L,
1604 Null_Present => False));
1606 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1607 L := Component_Items
1609 (Record_Extension_Part
1610 (Type_Definition (N))));
1612 L := Component_Items
1614 (Type_Definition (N)));
1617 -- Find the last tag component
1620 while Present (Comp) loop
1621 if Nkind (Comp) = N_Component_Declaration
1622 and then Is_Tag (Defining_Identifier (Comp))
1631 -- At this point L references the list of components and Last_Tag
1632 -- references the current last tag (if any). Now we add the tag
1633 -- corresponding with all the interfaces that are not implemented
1636 if Present (Interfaces (Typ)) then
1637 Elmt := First_Elmt (Interfaces (Typ));
1638 while Present (Elmt) loop
1639 Add_Tag (Node (Elmt));
1643 end Add_Interface_Tag_Components;
1645 -------------------------------------
1646 -- Add_Internal_Interface_Entities --
1647 -------------------------------------
1649 procedure Add_Internal_Interface_Entities (Tagged_Type : Entity_Id) is
1652 Iface_Elmt : Elmt_Id;
1653 Iface_Prim : Entity_Id;
1654 Ifaces_List : Elist_Id;
1655 New_Subp : Entity_Id := Empty;
1657 Restore_Scope : Boolean := False;
1660 pragma Assert (Ada_Version >= Ada_2005
1661 and then Is_Record_Type (Tagged_Type)
1662 and then Is_Tagged_Type (Tagged_Type)
1663 and then Has_Interfaces (Tagged_Type)
1664 and then not Is_Interface (Tagged_Type));
1666 -- Ensure that the internal entities are added to the scope of the type
1668 if Scope (Tagged_Type) /= Current_Scope then
1669 Push_Scope (Scope (Tagged_Type));
1670 Restore_Scope := True;
1673 Collect_Interfaces (Tagged_Type, Ifaces_List);
1675 Iface_Elmt := First_Elmt (Ifaces_List);
1676 while Present (Iface_Elmt) loop
1677 Iface := Node (Iface_Elmt);
1679 -- Originally we excluded here from this processing interfaces that
1680 -- are parents of Tagged_Type because their primitives are located
1681 -- in the primary dispatch table (and hence no auxiliary internal
1682 -- entities are required to handle secondary dispatch tables in such
1683 -- case). However, these auxiliary entities are also required to
1684 -- handle derivations of interfaces in formals of generics (see
1685 -- Derive_Subprograms).
1687 Elmt := First_Elmt (Primitive_Operations (Iface));
1688 while Present (Elmt) loop
1689 Iface_Prim := Node (Elmt);
1691 if not Is_Predefined_Dispatching_Operation (Iface_Prim) then
1693 Find_Primitive_Covering_Interface
1694 (Tagged_Type => Tagged_Type,
1695 Iface_Prim => Iface_Prim);
1697 if No (Prim) and then Serious_Errors_Detected > 0 then
1701 pragma Assert (Present (Prim));
1703 -- Ada 2012 (AI05-0197): If the name of the covering primitive
1704 -- differs from the name of the interface primitive then it is
1705 -- a private primitive inherited from a parent type. In such
1706 -- case, given that Tagged_Type covers the interface, the
1707 -- inherited private primitive becomes visible. For such
1708 -- purpose we add a new entity that renames the inherited
1709 -- private primitive.
1711 if Chars (Prim) /= Chars (Iface_Prim) then
1712 pragma Assert (Has_Suffix (Prim, 'P'));
1714 (New_Subp => New_Subp,
1715 Parent_Subp => Iface_Prim,
1716 Derived_Type => Tagged_Type,
1717 Parent_Type => Iface);
1718 Set_Alias (New_Subp, Prim);
1719 Set_Is_Abstract_Subprogram
1720 (New_Subp, Is_Abstract_Subprogram (Prim));
1724 (New_Subp => New_Subp,
1725 Parent_Subp => Iface_Prim,
1726 Derived_Type => Tagged_Type,
1727 Parent_Type => Iface);
1729 -- Ada 2005 (AI-251): Decorate internal entity Iface_Subp
1730 -- associated with interface types. These entities are
1731 -- only registered in the list of primitives of its
1732 -- corresponding tagged type because they are only used
1733 -- to fill the contents of the secondary dispatch tables.
1734 -- Therefore they are removed from the homonym chains.
1736 Set_Is_Hidden (New_Subp);
1737 Set_Is_Internal (New_Subp);
1738 Set_Alias (New_Subp, Prim);
1739 Set_Is_Abstract_Subprogram
1740 (New_Subp, Is_Abstract_Subprogram (Prim));
1741 Set_Interface_Alias (New_Subp, Iface_Prim);
1743 -- If the returned type is an interface then propagate it to
1744 -- the returned type. Needed by the thunk to generate the code
1745 -- which displaces "this" to reference the corresponding
1746 -- secondary dispatch table in the returned object.
1748 if Is_Interface (Etype (Iface_Prim)) then
1749 Set_Etype (New_Subp, Etype (Iface_Prim));
1752 -- Internal entities associated with interface types are only
1753 -- registered in the list of primitives of the tagged type.
1754 -- They are only used to fill the contents of the secondary
1755 -- dispatch tables. Therefore they are not needed in the
1758 Remove_Homonym (New_Subp);
1760 -- Hidden entities associated with interfaces must have set
1761 -- the Has_Delay_Freeze attribute to ensure that, in case
1762 -- of locally defined tagged types (or compiling with static
1763 -- dispatch tables generation disabled) the corresponding
1764 -- entry of the secondary dispatch table is filled when such
1765 -- an entity is frozen. This is an expansion activity that must
1766 -- be suppressed for ASIS because it leads to gigi elaboration
1767 -- issues in annotate mode.
1769 if not ASIS_Mode then
1770 Set_Has_Delayed_Freeze (New_Subp);
1778 Next_Elmt (Iface_Elmt);
1781 if Restore_Scope then
1784 end Add_Internal_Interface_Entities;
1786 -----------------------------------
1787 -- Analyze_Component_Declaration --
1788 -----------------------------------
1790 procedure Analyze_Component_Declaration (N : Node_Id) is
1791 Loc : constant Source_Ptr := Sloc (Component_Definition (N));
1792 Id : constant Entity_Id := Defining_Identifier (N);
1793 E : constant Node_Id := Expression (N);
1794 Typ : constant Node_Id :=
1795 Subtype_Indication (Component_Definition (N));
1799 function Contains_POC (Constr : Node_Id) return Boolean;
1800 -- Determines whether a constraint uses the discriminant of a record
1801 -- type thus becoming a per-object constraint (POC).
1803 function Is_Known_Limited (Typ : Entity_Id) return Boolean;
1804 -- Typ is the type of the current component, check whether this type is
1805 -- a limited type. Used to validate declaration against that of
1806 -- enclosing record.
1812 function Contains_POC (Constr : Node_Id) return Boolean is
1814 -- Prevent cascaded errors
1816 if Error_Posted (Constr) then
1820 case Nkind (Constr) is
1821 when N_Attribute_Reference =>
1822 return Attribute_Name (Constr) = Name_Access
1823 and then Prefix (Constr) = Scope (Entity (Prefix (Constr)));
1825 when N_Discriminant_Association =>
1826 return Denotes_Discriminant (Expression (Constr));
1828 when N_Identifier =>
1829 return Denotes_Discriminant (Constr);
1831 when N_Index_Or_Discriminant_Constraint =>
1836 IDC := First (Constraints (Constr));
1837 while Present (IDC) loop
1839 -- One per-object constraint is sufficient
1841 if Contains_POC (IDC) then
1852 return Denotes_Discriminant (Low_Bound (Constr))
1854 Denotes_Discriminant (High_Bound (Constr));
1856 when N_Range_Constraint =>
1857 return Denotes_Discriminant (Range_Expression (Constr));
1865 ----------------------
1866 -- Is_Known_Limited --
1867 ----------------------
1869 function Is_Known_Limited (Typ : Entity_Id) return Boolean is
1870 P : constant Entity_Id := Etype (Typ);
1871 R : constant Entity_Id := Root_Type (Typ);
1874 if Is_Limited_Record (Typ) then
1877 -- If the root type is limited (and not a limited interface)
1878 -- so is the current type
1880 elsif Is_Limited_Record (R)
1881 and then (not Is_Interface (R) or else not Is_Limited_Interface (R))
1885 -- Else the type may have a limited interface progenitor, but a
1886 -- limited record parent.
1888 elsif R /= P and then Is_Limited_Record (P) then
1894 end Is_Known_Limited;
1896 -- Start of processing for Analyze_Component_Declaration
1899 Generate_Definition (Id);
1902 if Present (Typ) then
1903 T := Find_Type_Of_Object
1904 (Subtype_Indication (Component_Definition (N)), N);
1906 if not Nkind_In (Typ, N_Identifier, N_Expanded_Name) then
1907 Check_SPARK_05_Restriction ("subtype mark required", Typ);
1910 -- Ada 2005 (AI-230): Access Definition case
1913 pragma Assert (Present
1914 (Access_Definition (Component_Definition (N))));
1916 T := Access_Definition
1918 N => Access_Definition (Component_Definition (N)));
1919 Set_Is_Local_Anonymous_Access (T);
1921 -- Ada 2005 (AI-254)
1923 if Present (Access_To_Subprogram_Definition
1924 (Access_Definition (Component_Definition (N))))
1925 and then Protected_Present (Access_To_Subprogram_Definition
1927 (Component_Definition (N))))
1929 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1933 -- If the subtype is a constrained subtype of the enclosing record,
1934 -- (which must have a partial view) the back-end does not properly
1935 -- handle the recursion. Rewrite the component declaration with an
1936 -- explicit subtype indication, which is acceptable to Gigi. We can copy
1937 -- the tree directly because side effects have already been removed from
1938 -- discriminant constraints.
1940 if Ekind (T) = E_Access_Subtype
1941 and then Is_Entity_Name (Subtype_Indication (Component_Definition (N)))
1942 and then Comes_From_Source (T)
1943 and then Nkind (Parent (T)) = N_Subtype_Declaration
1944 and then Etype (Directly_Designated_Type (T)) = Current_Scope
1947 (Subtype_Indication (Component_Definition (N)),
1948 New_Copy_Tree (Subtype_Indication (Parent (T))));
1949 T := Find_Type_Of_Object
1950 (Subtype_Indication (Component_Definition (N)), N);
1953 -- If the component declaration includes a default expression, then we
1954 -- check that the component is not of a limited type (RM 3.7(5)),
1955 -- and do the special preanalysis of the expression (see section on
1956 -- "Handling of Default and Per-Object Expressions" in the spec of
1960 Check_SPARK_05_Restriction ("default expression is not allowed", E);
1961 Preanalyze_Default_Expression (E, T);
1962 Check_Initialization (T, E);
1964 if Ada_Version >= Ada_2005
1965 and then Ekind (T) = E_Anonymous_Access_Type
1966 and then Etype (E) /= Any_Type
1968 -- Check RM 3.9.2(9): "if the expected type for an expression is
1969 -- an anonymous access-to-specific tagged type, then the object
1970 -- designated by the expression shall not be dynamically tagged
1971 -- unless it is a controlling operand in a call on a dispatching
1974 if Is_Tagged_Type (Directly_Designated_Type (T))
1976 Ekind (Directly_Designated_Type (T)) /= E_Class_Wide_Type
1978 Ekind (Directly_Designated_Type (Etype (E))) =
1982 ("access to specific tagged type required (RM 3.9.2(9))", E);
1985 -- (Ada 2005: AI-230): Accessibility check for anonymous
1988 if Type_Access_Level (Etype (E)) >
1989 Deepest_Type_Access_Level (T)
1992 ("expression has deeper access level than component " &
1993 "(RM 3.10.2 (12.2))", E);
1996 -- The initialization expression is a reference to an access
1997 -- discriminant. The type of the discriminant is always deeper
1998 -- than any access type.
2000 if Ekind (Etype (E)) = E_Anonymous_Access_Type
2001 and then Is_Entity_Name (E)
2002 and then Ekind (Entity (E)) = E_In_Parameter
2003 and then Present (Discriminal_Link (Entity (E)))
2006 ("discriminant has deeper accessibility level than target",
2012 -- The parent type may be a private view with unknown discriminants,
2013 -- and thus unconstrained. Regular components must be constrained.
2015 if not Is_Definite_Subtype (T) and then Chars (Id) /= Name_uParent then
2016 if Is_Class_Wide_Type (T) then
2018 ("class-wide subtype with unknown discriminants" &
2019 " in component declaration",
2020 Subtype_Indication (Component_Definition (N)));
2023 ("unconstrained subtype in component declaration",
2024 Subtype_Indication (Component_Definition (N)));
2027 -- Components cannot be abstract, except for the special case of
2028 -- the _Parent field (case of extending an abstract tagged type)
2030 elsif Is_Abstract_Type (T) and then Chars (Id) /= Name_uParent then
2031 Error_Msg_N ("type of a component cannot be abstract", N);
2035 Set_Is_Aliased (Id, Aliased_Present (Component_Definition (N)));
2037 -- The component declaration may have a per-object constraint, set
2038 -- the appropriate flag in the defining identifier of the subtype.
2040 if Present (Subtype_Indication (Component_Definition (N))) then
2042 Sindic : constant Node_Id :=
2043 Subtype_Indication (Component_Definition (N));
2045 if Nkind (Sindic) = N_Subtype_Indication
2046 and then Present (Constraint (Sindic))
2047 and then Contains_POC (Constraint (Sindic))
2049 Set_Has_Per_Object_Constraint (Id);
2054 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
2055 -- out some static checks.
2057 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
2058 Null_Exclusion_Static_Checks (N);
2061 -- If this component is private (or depends on a private type), flag the
2062 -- record type to indicate that some operations are not available.
2064 P := Private_Component (T);
2068 -- Check for circular definitions
2070 if P = Any_Type then
2071 Set_Etype (Id, Any_Type);
2073 -- There is a gap in the visibility of operations only if the
2074 -- component type is not defined in the scope of the record type.
2076 elsif Scope (P) = Scope (Current_Scope) then
2079 elsif Is_Limited_Type (P) then
2080 Set_Is_Limited_Composite (Current_Scope);
2083 Set_Is_Private_Composite (Current_Scope);
2088 and then Is_Limited_Type (T)
2089 and then Chars (Id) /= Name_uParent
2090 and then Is_Tagged_Type (Current_Scope)
2092 if Is_Derived_Type (Current_Scope)
2093 and then not Is_Known_Limited (Current_Scope)
2096 ("extension of nonlimited type cannot have limited components",
2099 if Is_Interface (Root_Type (Current_Scope)) then
2101 ("\limitedness is not inherited from limited interface", N);
2102 Error_Msg_N ("\add LIMITED to type indication", N);
2105 Explain_Limited_Type (T, N);
2106 Set_Etype (Id, Any_Type);
2107 Set_Is_Limited_Composite (Current_Scope, False);
2109 elsif not Is_Derived_Type (Current_Scope)
2110 and then not Is_Limited_Record (Current_Scope)
2111 and then not Is_Concurrent_Type (Current_Scope)
2114 ("nonlimited tagged type cannot have limited components", N);
2115 Explain_Limited_Type (T, N);
2116 Set_Etype (Id, Any_Type);
2117 Set_Is_Limited_Composite (Current_Scope, False);
2121 -- If the component is an unconstrained task or protected type with
2122 -- discriminants, the component and the enclosing record are limited
2123 -- and the component is constrained by its default values. Compute
2124 -- its actual subtype, else it may be allocated the maximum size by
2125 -- the backend, and possibly overflow.
2127 if Is_Concurrent_Type (T)
2128 and then not Is_Constrained (T)
2129 and then Has_Discriminants (T)
2130 and then not Has_Discriminants (Current_Scope)
2133 Act_T : constant Entity_Id := Build_Default_Subtype (T, N);
2136 Set_Etype (Id, Act_T);
2138 -- Rewrite component definition to use the constrained subtype
2140 Rewrite (Component_Definition (N),
2141 Make_Component_Definition (Loc,
2142 Subtype_Indication => New_Occurrence_Of (Act_T, Loc)));
2146 Set_Original_Record_Component (Id, Id);
2148 if Has_Aspects (N) then
2149 Analyze_Aspect_Specifications (N, Id);
2152 Analyze_Dimension (N);
2153 end Analyze_Component_Declaration;
2155 --------------------------
2156 -- Analyze_Declarations --
2157 --------------------------
2159 procedure Analyze_Declarations (L : List_Id) is
2162 procedure Adjust_Decl;
2163 -- Adjust Decl not to include implicit label declarations, since these
2164 -- have strange Sloc values that result in elaboration check problems.
2165 -- (They have the sloc of the label as found in the source, and that
2166 -- is ahead of the current declarative part).
2168 procedure Check_Entry_Contracts;
2169 -- Perform a pre-analysis of the pre- and postconditions of an entry
2170 -- declaration. This must be done before full resolution and creation
2171 -- of the parameter block, etc. to catch illegal uses within the
2172 -- contract expression. Full analysis of the expression is done when
2173 -- the contract is processed.
2175 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id);
2176 -- Determine whether Body_Decl denotes the body of a late controlled
2177 -- primitive (either Initialize, Adjust or Finalize). If this is the
2178 -- case, add a proper spec if the body lacks one. The spec is inserted
2179 -- before Body_Decl and immediately analyzed.
2181 procedure Remove_Partial_Visible_Refinements (Spec_Id : Entity_Id);
2182 -- Spec_Id is the entity of a package that may define abstract states,
2183 -- and in the case of a child unit, whose ancestors may define abstract
2184 -- states. If the states have partial visible refinement, remove the
2185 -- partial visibility of each constituent at the end of the package
2186 -- spec and body declarations.
2188 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id);
2189 -- Spec_Id is the entity of a package that may define abstract states.
2190 -- If the states have visible refinement, remove the visibility of each
2191 -- constituent at the end of the package body declaration.
2197 procedure Adjust_Decl is
2199 while Present (Prev (Decl))
2200 and then Nkind (Decl) = N_Implicit_Label_Declaration
2206 ---------------------------
2207 -- Check_Entry_Contracts --
2208 ---------------------------
2210 procedure Check_Entry_Contracts is
2216 Ent := First_Entity (Current_Scope);
2217 while Present (Ent) loop
2219 -- This only concerns entries with pre/postconditions
2221 if Ekind (Ent) = E_Entry
2222 and then Present (Contract (Ent))
2223 and then Present (Pre_Post_Conditions (Contract (Ent)))
2225 ASN := Pre_Post_Conditions (Contract (Ent));
2227 Install_Formals (Ent);
2229 -- Pre/postconditions are rewritten as Check pragmas. Analysis
2230 -- is performed on a copy of the pragma expression, to prevent
2231 -- modifying the original expression.
2233 while Present (ASN) loop
2234 if Nkind (ASN) = N_Pragma then
2238 (First (Pragma_Argument_Associations (ASN))));
2239 Set_Parent (Exp, ASN);
2241 -- ??? why not Preanalyze_Assert_Expression
2246 ASN := Next_Pragma (ASN);
2254 end Check_Entry_Contracts;
2256 --------------------------------------
2257 -- Handle_Late_Controlled_Primitive --
2258 --------------------------------------
2260 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id) is
2261 Body_Spec : constant Node_Id := Specification (Body_Decl);
2262 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2263 Loc : constant Source_Ptr := Sloc (Body_Id);
2264 Params : constant List_Id :=
2265 Parameter_Specifications (Body_Spec);
2267 Spec_Id : Entity_Id;
2271 -- Consider only procedure bodies whose name matches one of the three
2272 -- controlled primitives.
2274 if Nkind (Body_Spec) /= N_Procedure_Specification
2275 or else not Nam_In (Chars (Body_Id), Name_Adjust,
2281 -- A controlled primitive must have exactly one formal which is not
2282 -- an anonymous access type.
2284 elsif List_Length (Params) /= 1 then
2288 Typ := Parameter_Type (First (Params));
2290 if Nkind (Typ) = N_Access_Definition then
2296 -- The type of the formal must be derived from [Limited_]Controlled
2298 if not Is_Controlled (Entity (Typ)) then
2302 -- Check whether a specification exists for this body. We do not
2303 -- analyze the spec of the body in full, because it will be analyzed
2304 -- again when the body is properly analyzed, and we cannot create
2305 -- duplicate entries in the formals chain. We look for an explicit
2306 -- specification because the body may be an overriding operation and
2307 -- an inherited spec may be present.
2309 Spec_Id := Current_Entity (Body_Id);
2311 while Present (Spec_Id) loop
2312 if Ekind_In (Spec_Id, E_Procedure, E_Generic_Procedure)
2313 and then Scope (Spec_Id) = Current_Scope
2314 and then Present (First_Formal (Spec_Id))
2315 and then No (Next_Formal (First_Formal (Spec_Id)))
2316 and then Etype (First_Formal (Spec_Id)) = Entity (Typ)
2317 and then Comes_From_Source (Spec_Id)
2322 Spec_Id := Homonym (Spec_Id);
2325 -- At this point the body is known to be a late controlled primitive.
2326 -- Generate a matching spec and insert it before the body. Note the
2327 -- use of Copy_Separate_Tree - we want an entirely separate semantic
2328 -- tree in this case.
2330 Spec := Copy_Separate_Tree (Body_Spec);
2332 -- Ensure that the subprogram declaration does not inherit the null
2333 -- indicator from the body as we now have a proper spec/body pair.
2335 Set_Null_Present (Spec, False);
2337 -- Ensure that the freeze node is inserted after the declaration of
2338 -- the primitive since its expansion will freeze the primitive.
2340 Decl := Make_Subprogram_Declaration (Loc, Specification => Spec);
2342 Insert_Before_And_Analyze (Body_Decl, Decl);
2343 end Handle_Late_Controlled_Primitive;
2345 ----------------------------------------
2346 -- Remove_Partial_Visible_Refinements --
2347 ----------------------------------------
2349 procedure Remove_Partial_Visible_Refinements (Spec_Id : Entity_Id) is
2350 State_Elmt : Elmt_Id;
2352 if Present (Abstract_States (Spec_Id)) then
2353 State_Elmt := First_Elmt (Abstract_States (Spec_Id));
2354 while Present (State_Elmt) loop
2355 Set_Has_Partial_Visible_Refinement (Node (State_Elmt), False);
2356 Next_Elmt (State_Elmt);
2360 -- For a child unit, also hide the partial state refinement from
2361 -- ancestor packages.
2363 if Is_Child_Unit (Spec_Id) then
2364 Remove_Partial_Visible_Refinements (Scope (Spec_Id));
2366 end Remove_Partial_Visible_Refinements;
2368 --------------------------------
2369 -- Remove_Visible_Refinements --
2370 --------------------------------
2372 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id) is
2373 State_Elmt : Elmt_Id;
2375 if Present (Abstract_States (Spec_Id)) then
2376 State_Elmt := First_Elmt (Abstract_States (Spec_Id));
2377 while Present (State_Elmt) loop
2378 Set_Has_Visible_Refinement (Node (State_Elmt), False);
2379 Next_Elmt (State_Elmt);
2382 end Remove_Visible_Refinements;
2386 Context : Node_Id := Empty;
2387 Freeze_From : Entity_Id := Empty;
2388 Next_Decl : Node_Id;
2390 Body_Seen : Boolean := False;
2391 -- Flag set when the first body [stub] is encountered
2393 -- Start of processing for Analyze_Declarations
2396 if Restriction_Check_Required (SPARK_05) then
2397 Check_Later_Vs_Basic_Declarations (L, During_Parsing => False);
2401 while Present (Decl) loop
2403 -- Package spec cannot contain a package declaration in SPARK
2405 if Nkind (Decl) = N_Package_Declaration
2406 and then Nkind (Parent (L)) = N_Package_Specification
2408 Check_SPARK_05_Restriction
2409 ("package specification cannot contain a package declaration",
2413 -- Complete analysis of declaration
2416 Next_Decl := Next (Decl);
2418 if No (Freeze_From) then
2419 Freeze_From := First_Entity (Current_Scope);
2422 -- At the end of a declarative part, freeze remaining entities
2423 -- declared in it. The end of the visible declarations of package
2424 -- specification is not the end of a declarative part if private
2425 -- declarations are present. The end of a package declaration is a
2426 -- freezing point only if it a library package. A task definition or
2427 -- protected type definition is not a freeze point either. Finally,
2428 -- we do not freeze entities in generic scopes, because there is no
2429 -- code generated for them and freeze nodes will be generated for
2432 -- The end of a package instantiation is not a freeze point, but
2433 -- for now we make it one, because the generic body is inserted
2434 -- (currently) immediately after. Generic instantiations will not
2435 -- be a freeze point once delayed freezing of bodies is implemented.
2436 -- (This is needed in any case for early instantiations ???).
2438 if No (Next_Decl) then
2439 if Nkind (Parent (L)) = N_Component_List then
2442 elsif Nkind_In (Parent (L), N_Protected_Definition,
2445 Check_Entry_Contracts;
2447 elsif Nkind (Parent (L)) /= N_Package_Specification then
2448 if Nkind (Parent (L)) = N_Package_Body then
2449 Freeze_From := First_Entity (Current_Scope);
2452 -- There may have been several freezing points previously,
2453 -- for example object declarations or subprogram bodies, but
2454 -- at the end of a declarative part we check freezing from
2455 -- the beginning, even though entities may already be frozen,
2456 -- in order to perform visibility checks on delayed aspects.
2459 Freeze_All (First_Entity (Current_Scope), Decl);
2460 Freeze_From := Last_Entity (Current_Scope);
2462 elsif Scope (Current_Scope) /= Standard_Standard
2463 and then not Is_Child_Unit (Current_Scope)
2464 and then No (Generic_Parent (Parent (L)))
2468 elsif L /= Visible_Declarations (Parent (L))
2469 or else No (Private_Declarations (Parent (L)))
2470 or else Is_Empty_List (Private_Declarations (Parent (L)))
2473 Freeze_All (First_Entity (Current_Scope), Decl);
2474 Freeze_From := Last_Entity (Current_Scope);
2476 -- At the end of the visible declarations the expressions in
2477 -- aspects of all entities declared so far must be resolved.
2478 -- The entities themselves might be frozen later, and the
2479 -- generated pragmas and attribute definition clauses analyzed
2480 -- in full at that point, but name resolution must take place
2482 -- In addition to being the proper semantics, this is mandatory
2483 -- within generic units, because global name capture requires
2484 -- those expressions to be analyzed, given that the generated
2485 -- pragmas do not appear in the original generic tree.
2487 elsif Serious_Errors_Detected = 0 then
2492 E := First_Entity (Current_Scope);
2493 while Present (E) loop
2494 Resolve_Aspect_Expressions (E);
2500 -- If next node is a body then freeze all types before the body.
2501 -- An exception occurs for some expander-generated bodies. If these
2502 -- are generated at places where in general language rules would not
2503 -- allow a freeze point, then we assume that the expander has
2504 -- explicitly checked that all required types are properly frozen,
2505 -- and we do not cause general freezing here. This special circuit
2506 -- is used when the encountered body is marked as having already
2509 -- In all other cases (bodies that come from source, and expander
2510 -- generated bodies that have not been analyzed yet), freeze all
2511 -- types now. Note that in the latter case, the expander must take
2512 -- care to attach the bodies at a proper place in the tree so as to
2513 -- not cause unwanted freezing at that point.
2515 elsif not Analyzed (Next_Decl) and then Is_Body (Next_Decl) then
2517 -- When a controlled type is frozen, the expander generates stream
2518 -- and controlled type support routines. If the freeze is caused
2519 -- by the stand alone body of Initialize, Adjust and Finalize, the
2520 -- expander will end up using the wrong version of these routines
2521 -- as the body has not been processed yet. To remedy this, detect
2522 -- a late controlled primitive and create a proper spec for it.
2523 -- This ensures that the primitive will override its inherited
2524 -- counterpart before the freeze takes place.
2526 -- If the declaration we just processed is a body, do not attempt
2527 -- to examine Next_Decl as the late primitive idiom can only apply
2528 -- to the first encountered body.
2530 -- The spec of the late primitive is not generated in ASIS mode to
2531 -- ensure a consistent list of primitives that indicates the true
2532 -- semantic structure of the program (which is not relevant when
2533 -- generating executable code.
2535 -- ??? a cleaner approach may be possible and/or this solution
2536 -- could be extended to general-purpose late primitives, TBD.
2538 if not ASIS_Mode and then not Body_Seen and then not Is_Body (Decl)
2542 if Nkind (Next_Decl) = N_Subprogram_Body then
2543 Handle_Late_Controlled_Primitive (Next_Decl);
2548 Freeze_All (Freeze_From, Decl);
2549 Freeze_From := Last_Entity (Current_Scope);
2555 -- Analyze the contracts of packages and their bodies
2558 Context := Parent (L);
2560 if Nkind (Context) = N_Package_Specification then
2562 -- When a package has private declarations, its contract must be
2563 -- analyzed at the end of the said declarations. This way both the
2564 -- analysis and freeze actions are properly synchronized in case
2565 -- of private type use within the contract.
2567 if L = Private_Declarations (Context) then
2568 Analyze_Package_Contract (Defining_Entity (Context));
2570 -- Build the bodies of the default initial condition procedures
2571 -- for all types subject to pragma Default_Initial_Condition.
2572 -- From a purely Ada stand point, this is a freezing activity,
2573 -- however freezing is not available under GNATprove_Mode. To
2574 -- accomodate both scenarios, the bodies are build at the end
2575 -- of private declaration analysis.
2577 Build_Default_Init_Cond_Procedure_Bodies (L);
2579 -- Otherwise the contract is analyzed at the end of the visible
2582 elsif L = Visible_Declarations (Context)
2583 and then No (Private_Declarations (Context))
2585 Analyze_Package_Contract (Defining_Entity (Context));
2588 elsif Nkind (Context) = N_Package_Body then
2589 Analyze_Package_Body_Contract (Defining_Entity (Context));
2592 -- Analyze the contracts of various constructs now due to the delayed
2593 -- visibility needs of their aspects and pragmas.
2595 Analyze_Contracts (L);
2597 if Nkind (Context) = N_Package_Body then
2599 -- Ensure that all abstract states and objects declared in the
2600 -- state space of a package body are utilized as constituents.
2602 Check_Unused_Body_States (Defining_Entity (Context));
2604 -- State refinements are visible up to the end of the package body
2605 -- declarations. Hide the state refinements from visibility to
2606 -- restore the original state conditions.
2608 Remove_Visible_Refinements (Corresponding_Spec (Context));
2609 Remove_Partial_Visible_Refinements (Corresponding_Spec (Context));
2611 elsif Nkind (Context) = N_Package_Declaration then
2613 -- Partial state refinements are visible up to the end of the
2614 -- package spec declarations. Hide the partial state refinements
2615 -- from visibility to restore the original state conditions.
2617 Remove_Partial_Visible_Refinements (Corresponding_Spec (Context));
2620 -- Verify that all abstract states found in any package declared in
2621 -- the input declarative list have proper refinements. The check is
2622 -- performed only when the context denotes a block, entry, package,
2623 -- protected, subprogram, or task body (SPARK RM 7.2.2(3)).
2625 Check_State_Refinements (Context);
2627 end Analyze_Declarations;
2629 -----------------------------------
2630 -- Analyze_Full_Type_Declaration --
2631 -----------------------------------
2633 procedure Analyze_Full_Type_Declaration (N : Node_Id) is
2634 Def : constant Node_Id := Type_Definition (N);
2635 Def_Id : constant Entity_Id := Defining_Identifier (N);
2639 Is_Remote : constant Boolean :=
2640 (Is_Remote_Types (Current_Scope)
2641 or else Is_Remote_Call_Interface (Current_Scope))
2642 and then not (In_Private_Part (Current_Scope)
2643 or else In_Package_Body (Current_Scope));
2645 procedure Check_Nonoverridable_Aspects;
2646 -- Apply the rule in RM 13.1.1(18.4/4) on iterator aspects that cannot
2647 -- be overridden, and can only be confirmed on derivation.
2649 procedure Check_Ops_From_Incomplete_Type;
2650 -- If there is a tagged incomplete partial view of the type, traverse
2651 -- the primitives of the incomplete view and change the type of any
2652 -- controlling formals and result to indicate the full view. The
2653 -- primitives will be added to the full type's primitive operations
2654 -- list later in Sem_Disp.Check_Operation_From_Incomplete_Type (which
2655 -- is called from Process_Incomplete_Dependents).
2657 ----------------------------------
2658 -- Check_Nonoverridable_Aspects --
2659 ----------------------------------
2661 procedure Check_Nonoverridable_Aspects is
2662 Prev_Aspects : constant List_Id :=
2663 Aspect_Specifications (Parent (Def_Id));
2664 Par_Type : Entity_Id;
2666 function Has_Aspect_Spec
2668 Aspect_Name : Name_Id) return Boolean;
2669 -- Check whether a list of aspect specifications includes an entry
2670 -- for a specific aspect. The list is either that of a partial or
2673 ---------------------
2674 -- Has_Aspect_Spec --
2675 ---------------------
2677 function Has_Aspect_Spec
2679 Aspect_Name : Name_Id) return Boolean
2683 Spec := First (Specs);
2684 while Present (Spec) loop
2685 if Chars (Identifier (Spec)) = Aspect_Name then
2691 end Has_Aspect_Spec;
2693 -- Start of processing for Check_Nonoverridable_Aspects
2697 -- Get parent type of derived type. Note that Prev is the entity
2698 -- in the partial declaration, but its contents are now those of
2699 -- full view, while Def_Id reflects the partial view.
2701 if Is_Private_Type (Def_Id) then
2702 Par_Type := Etype (Full_View (Def_Id));
2704 Par_Type := Etype (Def_Id);
2707 -- If there is an inherited Implicit_Dereference, verify that it is
2708 -- made explicit in the partial view.
2710 if Has_Discriminants (Base_Type (Par_Type))
2711 and then Nkind (Parent (Prev)) = N_Full_Type_Declaration
2712 and then Present (Discriminant_Specifications (Parent (Prev)))
2713 and then Present (Get_Reference_Discriminant (Par_Type))
2716 not Has_Aspect_Spec (Prev_Aspects, Name_Implicit_Dereference)
2719 ("type does not inherit implicit dereference", Prev);
2722 -- If one of the views has the aspect specified, verify that it
2723 -- is consistent with that of the parent.
2726 Par_Discr : constant Entity_Id :=
2727 Get_Reference_Discriminant (Par_Type);
2728 Cur_Discr : constant Entity_Id :=
2729 Get_Reference_Discriminant (Prev);
2731 if Corresponding_Discriminant (Cur_Discr) /= Par_Discr then
2732 Error_Msg_N ("aspect incosistent with that of parent", N);
2738 -- TBD : other nonoverridable aspects.
2739 end Check_Nonoverridable_Aspects;
2741 ------------------------------------
2742 -- Check_Ops_From_Incomplete_Type --
2743 ------------------------------------
2745 procedure Check_Ops_From_Incomplete_Type is
2752 and then Ekind (Prev) = E_Incomplete_Type
2753 and then Is_Tagged_Type (Prev)
2754 and then Is_Tagged_Type (T)
2756 Elmt := First_Elmt (Primitive_Operations (Prev));
2757 while Present (Elmt) loop
2760 Formal := First_Formal (Op);
2761 while Present (Formal) loop
2762 if Etype (Formal) = Prev then
2763 Set_Etype (Formal, T);
2766 Next_Formal (Formal);
2769 if Etype (Op) = Prev then
2776 end Check_Ops_From_Incomplete_Type;
2778 -- Start of processing for Analyze_Full_Type_Declaration
2781 Prev := Find_Type_Name (N);
2783 -- The full view, if present, now points to the current type. If there
2784 -- is an incomplete partial view, set a link to it, to simplify the
2785 -- retrieval of primitive operations of the type.
2787 -- Ada 2005 (AI-50217): If the type was previously decorated when
2788 -- imported through a LIMITED WITH clause, it appears as incomplete
2789 -- but has no full view.
2791 if Ekind (Prev) = E_Incomplete_Type
2792 and then Present (Full_View (Prev))
2794 T := Full_View (Prev);
2795 Set_Incomplete_View (N, Parent (Prev));
2800 Set_Is_Pure (T, Is_Pure (Current_Scope));
2802 -- We set the flag Is_First_Subtype here. It is needed to set the
2803 -- corresponding flag for the Implicit class-wide-type created
2804 -- during tagged types processing.
2806 Set_Is_First_Subtype (T, True);
2808 -- Only composite types other than array types are allowed to have
2813 -- For derived types, the rule will be checked once we've figured
2814 -- out the parent type.
2816 when N_Derived_Type_Definition =>
2819 -- For record types, discriminants are allowed, unless we are in
2822 when N_Record_Definition =>
2823 if Present (Discriminant_Specifications (N)) then
2824 Check_SPARK_05_Restriction
2825 ("discriminant type is not allowed",
2827 (First (Discriminant_Specifications (N))));
2831 if Present (Discriminant_Specifications (N)) then
2833 ("elementary or array type cannot have discriminants",
2835 (First (Discriminant_Specifications (N))));
2839 -- Elaborate the type definition according to kind, and generate
2840 -- subsidiary (implicit) subtypes where needed. We skip this if it was
2841 -- already done (this happens during the reanalysis that follows a call
2842 -- to the high level optimizer).
2844 if not Analyzed (T) then
2847 -- A type declared within a Ghost region is automatically Ghost
2848 -- (SPARK RM 6.9(2)).
2850 if Ghost_Mode > None then
2851 Set_Is_Ghost_Entity (T);
2855 when N_Access_To_Subprogram_Definition =>
2856 Access_Subprogram_Declaration (T, Def);
2858 -- If this is a remote access to subprogram, we must create the
2859 -- equivalent fat pointer type, and related subprograms.
2862 Process_Remote_AST_Declaration (N);
2865 -- Validate categorization rule against access type declaration
2866 -- usually a violation in Pure unit, Shared_Passive unit.
2868 Validate_Access_Type_Declaration (T, N);
2870 when N_Access_To_Object_Definition =>
2871 Access_Type_Declaration (T, Def);
2873 -- Validate categorization rule against access type declaration
2874 -- usually a violation in Pure unit, Shared_Passive unit.
2876 Validate_Access_Type_Declaration (T, N);
2878 -- If we are in a Remote_Call_Interface package and define a
2879 -- RACW, then calling stubs and specific stream attributes
2883 and then Is_Remote_Access_To_Class_Wide_Type (Def_Id)
2885 Add_RACW_Features (Def_Id);
2888 when N_Array_Type_Definition =>
2889 Array_Type_Declaration (T, Def);
2891 when N_Derived_Type_Definition =>
2892 Derived_Type_Declaration (T, N, T /= Def_Id);
2894 when N_Enumeration_Type_Definition =>
2895 Enumeration_Type_Declaration (T, Def);
2897 when N_Floating_Point_Definition =>
2898 Floating_Point_Type_Declaration (T, Def);
2900 when N_Decimal_Fixed_Point_Definition =>
2901 Decimal_Fixed_Point_Type_Declaration (T, Def);
2903 when N_Ordinary_Fixed_Point_Definition =>
2904 Ordinary_Fixed_Point_Type_Declaration (T, Def);
2906 when N_Signed_Integer_Type_Definition =>
2907 Signed_Integer_Type_Declaration (T, Def);
2909 when N_Modular_Type_Definition =>
2910 Modular_Type_Declaration (T, Def);
2912 when N_Record_Definition =>
2913 Record_Type_Declaration (T, N, Prev);
2915 -- If declaration has a parse error, nothing to elaborate.
2921 raise Program_Error;
2926 if Etype (T) = Any_Type then
2930 -- Controlled type is not allowed in SPARK
2932 if Is_Visibly_Controlled (T) then
2933 Check_SPARK_05_Restriction ("controlled type is not allowed", N);
2936 -- Some common processing for all types
2938 Set_Depends_On_Private (T, Has_Private_Component (T));
2939 Check_Ops_From_Incomplete_Type;
2941 -- Both the declared entity, and its anonymous base type if one was
2942 -- created, need freeze nodes allocated.
2945 B : constant Entity_Id := Base_Type (T);
2948 -- In the case where the base type differs from the first subtype, we
2949 -- pre-allocate a freeze node, and set the proper link to the first
2950 -- subtype. Freeze_Entity will use this preallocated freeze node when
2951 -- it freezes the entity.
2953 -- This does not apply if the base type is a generic type, whose
2954 -- declaration is independent of the current derived definition.
2956 if B /= T and then not Is_Generic_Type (B) then
2957 Ensure_Freeze_Node (B);
2958 Set_First_Subtype_Link (Freeze_Node (B), T);
2961 -- A type that is imported through a limited_with clause cannot
2962 -- generate any code, and thus need not be frozen. However, an access
2963 -- type with an imported designated type needs a finalization list,
2964 -- which may be referenced in some other package that has non-limited
2965 -- visibility on the designated type. Thus we must create the
2966 -- finalization list at the point the access type is frozen, to
2967 -- prevent unsatisfied references at link time.
2969 if not From_Limited_With (T) or else Is_Access_Type (T) then
2970 Set_Has_Delayed_Freeze (T);
2974 -- Case where T is the full declaration of some private type which has
2975 -- been swapped in Defining_Identifier (N).
2977 if T /= Def_Id and then Is_Private_Type (Def_Id) then
2978 Process_Full_View (N, T, Def_Id);
2980 -- Record the reference. The form of this is a little strange, since
2981 -- the full declaration has been swapped in. So the first parameter
2982 -- here represents the entity to which a reference is made which is
2983 -- the "real" entity, i.e. the one swapped in, and the second
2984 -- parameter provides the reference location.
2986 -- Also, we want to kill Has_Pragma_Unreferenced temporarily here
2987 -- since we don't want a complaint about the full type being an
2988 -- unwanted reference to the private type
2991 B : constant Boolean := Has_Pragma_Unreferenced (T);
2993 Set_Has_Pragma_Unreferenced (T, False);
2994 Generate_Reference (T, T, 'c');
2995 Set_Has_Pragma_Unreferenced (T, B);
2998 Set_Completion_Referenced (Def_Id);
3000 -- For completion of incomplete type, process incomplete dependents
3001 -- and always mark the full type as referenced (it is the incomplete
3002 -- type that we get for any real reference).
3004 elsif Ekind (Prev) = E_Incomplete_Type then
3005 Process_Incomplete_Dependents (N, T, Prev);
3006 Generate_Reference (Prev, Def_Id, 'c');
3007 Set_Completion_Referenced (Def_Id);
3009 -- If not private type or incomplete type completion, this is a real
3010 -- definition of a new entity, so record it.
3013 Generate_Definition (Def_Id);
3016 -- Propagate any pending access types whose finalization masters need to
3017 -- be fully initialized from the partial to the full view. Guard against
3018 -- an illegal full view that remains unanalyzed.
3020 if Is_Type (Def_Id) and then Is_Incomplete_Or_Private_Type (Prev) then
3021 Set_Pending_Access_Types (Def_Id, Pending_Access_Types (Prev));
3024 if Chars (Scope (Def_Id)) = Name_System
3025 and then Chars (Def_Id) = Name_Address
3026 and then Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (N)))
3028 Set_Is_Descendant_Of_Address (Def_Id);
3029 Set_Is_Descendant_Of_Address (Base_Type (Def_Id));
3030 Set_Is_Descendant_Of_Address (Prev);
3033 Set_Optimize_Alignment_Flags (Def_Id);
3034 Check_Eliminated (Def_Id);
3036 -- If the declaration is a completion and aspects are present, apply
3037 -- them to the entity for the type which is currently the partial
3038 -- view, but which is the one that will be frozen.
3040 if Has_Aspects (N) then
3042 -- In most cases the partial view is a private type, and both views
3043 -- appear in different declarative parts. In the unusual case where
3044 -- the partial view is incomplete, perform the analysis on the
3045 -- full view, to prevent freezing anomalies with the corresponding
3046 -- class-wide type, which otherwise might be frozen before the
3047 -- dispatch table is built.
3050 and then Ekind (Prev) /= E_Incomplete_Type
3052 Analyze_Aspect_Specifications (N, Prev);
3057 Analyze_Aspect_Specifications (N, Def_Id);
3061 if Is_Derived_Type (Prev)
3062 and then Def_Id /= Prev
3064 Check_Nonoverridable_Aspects;
3066 end Analyze_Full_Type_Declaration;
3068 ----------------------------------
3069 -- Analyze_Incomplete_Type_Decl --
3070 ----------------------------------
3072 procedure Analyze_Incomplete_Type_Decl (N : Node_Id) is
3073 F : constant Boolean := Is_Pure (Current_Scope);
3077 Check_SPARK_05_Restriction ("incomplete type is not allowed", N);
3079 Generate_Definition (Defining_Identifier (N));
3081 -- Process an incomplete declaration. The identifier must not have been
3082 -- declared already in the scope. However, an incomplete declaration may
3083 -- appear in the private part of a package, for a private type that has
3084 -- already been declared.
3086 -- In this case, the discriminants (if any) must match
3088 T := Find_Type_Name (N);
3090 Set_Ekind (T, E_Incomplete_Type);
3091 Init_Size_Align (T);
3092 Set_Is_First_Subtype (T, True);
3095 -- An incomplete type declared within a Ghost region is automatically
3096 -- Ghost (SPARK RM 6.9(2)).
3098 if Ghost_Mode > None then
3099 Set_Is_Ghost_Entity (T);
3102 -- Ada 2005 (AI-326): Minimum decoration to give support to tagged
3103 -- incomplete types.
3105 if Tagged_Present (N) then
3106 Set_Is_Tagged_Type (T, True);
3107 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
3108 Make_Class_Wide_Type (T);
3109 Set_Direct_Primitive_Operations (T, New_Elmt_List);
3112 Set_Stored_Constraint (T, No_Elist);
3114 if Present (Discriminant_Specifications (N)) then
3116 Process_Discriminants (N);
3120 -- If the type has discriminants, nontrivial subtypes may be declared
3121 -- before the full view of the type. The full views of those subtypes
3122 -- will be built after the full view of the type.
3124 Set_Private_Dependents (T, New_Elmt_List);
3126 end Analyze_Incomplete_Type_Decl;
3128 -----------------------------------
3129 -- Analyze_Interface_Declaration --
3130 -----------------------------------
3132 procedure Analyze_Interface_Declaration (T : Entity_Id; Def : Node_Id) is
3133 CW : constant Entity_Id := Class_Wide_Type (T);
3136 Set_Is_Tagged_Type (T);
3137 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
3139 Set_Is_Limited_Record (T, Limited_Present (Def)
3140 or else Task_Present (Def)
3141 or else Protected_Present (Def)
3142 or else Synchronized_Present (Def));
3144 -- Type is abstract if full declaration carries keyword, or if previous
3145 -- partial view did.
3147 Set_Is_Abstract_Type (T);
3148 Set_Is_Interface (T);
3150 -- Type is a limited interface if it includes the keyword limited, task,
3151 -- protected, or synchronized.
3153 Set_Is_Limited_Interface
3154 (T, Limited_Present (Def)
3155 or else Protected_Present (Def)
3156 or else Synchronized_Present (Def)
3157 or else Task_Present (Def));
3159 Set_Interfaces (T, New_Elmt_List);
3160 Set_Direct_Primitive_Operations (T, New_Elmt_List);
3162 -- Complete the decoration of the class-wide entity if it was already
3163 -- built (i.e. during the creation of the limited view)
3165 if Present (CW) then
3166 Set_Is_Interface (CW);
3167 Set_Is_Limited_Interface (CW, Is_Limited_Interface (T));
3170 -- Check runtime support for synchronized interfaces
3172 if (Is_Task_Interface (T)
3173 or else Is_Protected_Interface (T)
3174 or else Is_Synchronized_Interface (T))
3175 and then not RTE_Available (RE_Select_Specific_Data)
3177 Error_Msg_CRT ("synchronized interfaces", T);
3179 end Analyze_Interface_Declaration;
3181 -----------------------------
3182 -- Analyze_Itype_Reference --
3183 -----------------------------
3185 -- Nothing to do. This node is placed in the tree only for the benefit of
3186 -- back end processing, and has no effect on the semantic processing.
3188 procedure Analyze_Itype_Reference (N : Node_Id) is
3190 pragma Assert (Is_Itype (Itype (N)));
3192 end Analyze_Itype_Reference;
3194 --------------------------------
3195 -- Analyze_Number_Declaration --
3196 --------------------------------
3198 procedure Analyze_Number_Declaration (N : Node_Id) is
3199 E : constant Node_Id := Expression (N);
3200 Id : constant Entity_Id := Defining_Identifier (N);
3201 Index : Interp_Index;
3206 Generate_Definition (Id);
3209 -- A number declared within a Ghost region is automatically Ghost
3210 -- (SPARK RM 6.9(2)).
3212 if Ghost_Mode > None then
3213 Set_Is_Ghost_Entity (Id);
3216 -- This is an optimization of a common case of an integer literal
3218 if Nkind (E) = N_Integer_Literal then
3219 Set_Is_Static_Expression (E, True);
3220 Set_Etype (E, Universal_Integer);
3222 Set_Etype (Id, Universal_Integer);
3223 Set_Ekind (Id, E_Named_Integer);
3224 Set_Is_Frozen (Id, True);
3228 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3230 -- Process expression, replacing error by integer zero, to avoid
3231 -- cascaded errors or aborts further along in the processing
3233 -- Replace Error by integer zero, which seems least likely to cause
3237 Rewrite (E, Make_Integer_Literal (Sloc (E), Uint_0));
3238 Set_Error_Posted (E);
3243 -- Verify that the expression is static and numeric. If
3244 -- the expression is overloaded, we apply the preference
3245 -- rule that favors root numeric types.
3247 if not Is_Overloaded (E) then
3249 if Has_Dynamic_Predicate_Aspect (T) then
3251 ("subtype has dynamic predicate, "
3252 & "not allowed in number declaration", N);
3258 Get_First_Interp (E, Index, It);
3259 while Present (It.Typ) loop
3260 if (Is_Integer_Type (It.Typ) or else Is_Real_Type (It.Typ))
3261 and then (Scope (Base_Type (It.Typ))) = Standard_Standard
3263 if T = Any_Type then
3266 elsif It.Typ = Universal_Real
3268 It.Typ = Universal_Integer
3270 -- Choose universal interpretation over any other
3277 Get_Next_Interp (Index, It);
3281 if Is_Integer_Type (T) then
3283 Set_Etype (Id, Universal_Integer);
3284 Set_Ekind (Id, E_Named_Integer);
3286 elsif Is_Real_Type (T) then
3288 -- Because the real value is converted to universal_real, this is a
3289 -- legal context for a universal fixed expression.
3291 if T = Universal_Fixed then
3293 Loc : constant Source_Ptr := Sloc (N);
3294 Conv : constant Node_Id := Make_Type_Conversion (Loc,
3296 New_Occurrence_Of (Universal_Real, Loc),
3297 Expression => Relocate_Node (E));
3304 elsif T = Any_Fixed then
3305 Error_Msg_N ("illegal context for mixed mode operation", E);
3307 -- Expression is of the form : universal_fixed * integer. Try to
3308 -- resolve as universal_real.
3310 T := Universal_Real;
3315 Set_Etype (Id, Universal_Real);
3316 Set_Ekind (Id, E_Named_Real);
3319 Wrong_Type (E, Any_Numeric);
3323 Set_Ekind (Id, E_Constant);
3324 Set_Never_Set_In_Source (Id, True);
3325 Set_Is_True_Constant (Id, True);
3329 if Nkind_In (E, N_Integer_Literal, N_Real_Literal) then
3330 Set_Etype (E, Etype (Id));
3333 if not Is_OK_Static_Expression (E) then
3334 Flag_Non_Static_Expr
3335 ("non-static expression used in number declaration!", E);
3336 Rewrite (E, Make_Integer_Literal (Sloc (N), 1));
3337 Set_Etype (E, Any_Type);
3340 Analyze_Dimension (N);
3341 end Analyze_Number_Declaration;
3343 --------------------------------
3344 -- Analyze_Object_Declaration --
3345 --------------------------------
3347 procedure Analyze_Object_Declaration (N : Node_Id) is
3348 Loc : constant Source_Ptr := Sloc (N);
3349 Id : constant Entity_Id := Defining_Identifier (N);
3353 E : Node_Id := Expression (N);
3354 -- E is set to Expression (N) throughout this routine. When
3355 -- Expression (N) is modified, E is changed accordingly.
3357 Prev_Entity : Entity_Id := Empty;
3359 function Count_Tasks (T : Entity_Id) return Uint;
3360 -- This function is called when a non-generic library level object of a
3361 -- task type is declared. Its function is to count the static number of
3362 -- tasks declared within the type (it is only called if Has_Task is set
3363 -- for T). As a side effect, if an array of tasks with non-static bounds
3364 -- or a variant record type is encountered, Check_Restriction is called
3365 -- indicating the count is unknown.
3367 function Delayed_Aspect_Present return Boolean;
3368 -- If the declaration has an expression that is an aggregate, and it
3369 -- has aspects that require delayed analysis, the resolution of the
3370 -- aggregate must be deferred to the freeze point of the objet. This
3371 -- special processing was created for address clauses, but it must
3372 -- also apply to Alignment. This must be done before the aspect
3373 -- specifications are analyzed because we must handle the aggregate
3374 -- before the analysis of the object declaration is complete.
3376 -- Any other relevant delayed aspects on object declarations ???
3382 function Count_Tasks (T : Entity_Id) return Uint is
3388 if Is_Task_Type (T) then
3391 elsif Is_Record_Type (T) then
3392 if Has_Discriminants (T) then
3393 Check_Restriction (Max_Tasks, N);
3398 C := First_Component (T);
3399 while Present (C) loop
3400 V := V + Count_Tasks (Etype (C));
3407 elsif Is_Array_Type (T) then
3408 X := First_Index (T);
3409 V := Count_Tasks (Component_Type (T));
3410 while Present (X) loop
3413 if not Is_OK_Static_Subtype (C) then
3414 Check_Restriction (Max_Tasks, N);
3417 V := V * (UI_Max (Uint_0,
3418 Expr_Value (Type_High_Bound (C)) -
3419 Expr_Value (Type_Low_Bound (C)) + Uint_1));
3432 ----------------------------
3433 -- Delayed_Aspect_Present --
3434 ----------------------------
3436 function Delayed_Aspect_Present return Boolean is
3441 if Present (Aspect_Specifications (N)) then
3442 A := First (Aspect_Specifications (N));
3443 A_Id := Get_Aspect_Id (Chars (Identifier (A)));
3444 while Present (A) loop
3445 if A_Id = Aspect_Alignment or else A_Id = Aspect_Address then
3454 end Delayed_Aspect_Present;
3458 Save_Ghost_Mode : constant Ghost_Mode_Type := Ghost_Mode;
3459 Related_Id : Entity_Id;
3461 -- Start of processing for Analyze_Object_Declaration
3464 -- There are three kinds of implicit types generated by an
3465 -- object declaration:
3467 -- 1. Those generated by the original Object Definition
3469 -- 2. Those generated by the Expression
3471 -- 3. Those used to constrain the Object Definition with the
3472 -- expression constraints when the definition is unconstrained.
3474 -- They must be generated in this order to avoid order of elaboration
3475 -- issues. Thus the first step (after entering the name) is to analyze
3476 -- the object definition.
3478 if Constant_Present (N) then
3479 Prev_Entity := Current_Entity_In_Scope (Id);
3481 if Present (Prev_Entity)
3483 -- If the homograph is an implicit subprogram, it is overridden
3484 -- by the current declaration.
3486 ((Is_Overloadable (Prev_Entity)
3487 and then Is_Inherited_Operation (Prev_Entity))
3489 -- The current object is a discriminal generated for an entry
3490 -- family index. Even though the index is a constant, in this
3491 -- particular context there is no true constant redeclaration.
3492 -- Enter_Name will handle the visibility.
3495 (Is_Discriminal (Id)
3496 and then Ekind (Discriminal_Link (Id)) =
3497 E_Entry_Index_Parameter)
3499 -- The current object is the renaming for a generic declared
3500 -- within the instance.
3503 (Ekind (Prev_Entity) = E_Package
3504 and then Nkind (Parent (Prev_Entity)) =
3505 N_Package_Renaming_Declaration
3506 and then not Comes_From_Source (Prev_Entity)
3508 Is_Generic_Instance (Renamed_Entity (Prev_Entity)))
3510 -- The entity may be a homonym of a private component of the
3511 -- enclosing protected object, for which we create a local
3512 -- renaming declaration. The declaration is legal, even if
3513 -- useless when it just captures that component.
3516 (Ekind (Scope (Current_Scope)) = E_Protected_Type
3517 and then Nkind (Parent (Prev_Entity)) =
3518 N_Object_Renaming_Declaration))
3520 Prev_Entity := Empty;
3524 -- The object declaration is Ghost when it is subject to pragma Ghost or
3525 -- completes a deferred Ghost constant. Set the mode now to ensure that
3526 -- any nodes generated during analysis and expansion are properly marked
3529 Set_Ghost_Mode (N, Prev_Entity);
3531 if Present (Prev_Entity) then
3532 Constant_Redeclaration (Id, N, T);
3534 Generate_Reference (Prev_Entity, Id, 'c');
3535 Set_Completion_Referenced (Id);
3537 if Error_Posted (N) then
3539 -- Type mismatch or illegal redeclaration; do not analyze
3540 -- expression to avoid cascaded errors.
3542 T := Find_Type_Of_Object (Object_Definition (N), N);
3544 Set_Ekind (Id, E_Variable);
3548 -- In the normal case, enter identifier at the start to catch premature
3549 -- usage in the initialization expression.
3552 Generate_Definition (Id);
3555 Mark_Coextensions (N, Object_Definition (N));
3557 T := Find_Type_Of_Object (Object_Definition (N), N);
3559 if Nkind (Object_Definition (N)) = N_Access_Definition
3561 (Access_To_Subprogram_Definition (Object_Definition (N)))
3562 and then Protected_Present
3563 (Access_To_Subprogram_Definition (Object_Definition (N)))
3565 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
3568 if Error_Posted (Id) then
3570 Set_Ekind (Id, E_Variable);
3575 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
3576 -- out some static checks.
3578 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
3580 -- In case of aggregates we must also take care of the correct
3581 -- initialization of nested aggregates bug this is done at the
3582 -- point of the analysis of the aggregate (see sem_aggr.adb) ???
3584 if Present (Expression (N))
3585 and then Nkind (Expression (N)) = N_Aggregate
3591 Save_Typ : constant Entity_Id := Etype (Id);
3593 Set_Etype (Id, T); -- Temp. decoration for static checks
3594 Null_Exclusion_Static_Checks (N);
3595 Set_Etype (Id, Save_Typ);
3600 -- Object is marked pure if it is in a pure scope
3602 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3604 -- If deferred constant, make sure context is appropriate. We detect
3605 -- a deferred constant as a constant declaration with no expression.
3606 -- A deferred constant can appear in a package body if its completion
3607 -- is by means of an interface pragma.
3609 if Constant_Present (N) and then No (E) then
3611 -- A deferred constant may appear in the declarative part of the
3612 -- following constructs:
3616 -- extended return statements
3619 -- subprogram bodies
3622 -- When declared inside a package spec, a deferred constant must be
3623 -- completed by a full constant declaration or pragma Import. In all
3624 -- other cases, the only proper completion is pragma Import. Extended
3625 -- return statements are flagged as invalid contexts because they do
3626 -- not have a declarative part and so cannot accommodate the pragma.
3628 if Ekind (Current_Scope) = E_Return_Statement then
3630 ("invalid context for deferred constant declaration (RM 7.4)",
3633 ("\declaration requires an initialization expression",
3635 Set_Constant_Present (N, False);
3637 -- In Ada 83, deferred constant must be of private type
3639 elsif not Is_Private_Type (T) then
3640 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
3642 ("(Ada 83) deferred constant must be private type", N);
3646 -- If not a deferred constant, then the object declaration freezes
3647 -- its type, unless the object is of an anonymous type and has delayed
3648 -- aspects. In that case the type is frozen when the object itself is.
3651 Check_Fully_Declared (T, N);
3653 if Has_Delayed_Aspects (Id)
3654 and then Is_Array_Type (T)
3655 and then Is_Itype (T)
3657 Set_Has_Delayed_Freeze (T);
3659 Freeze_Before (N, T);
3663 -- If the object was created by a constrained array definition, then
3664 -- set the link in both the anonymous base type and anonymous subtype
3665 -- that are built to represent the array type to point to the object.
3667 if Nkind (Object_Definition (Declaration_Node (Id))) =
3668 N_Constrained_Array_Definition
3670 Set_Related_Array_Object (T, Id);
3671 Set_Related_Array_Object (Base_Type (T), Id);
3674 -- Special checks for protected objects not at library level
3676 if Has_Protected (T) and then not Is_Library_Level_Entity (Id) then
3677 Check_Restriction (No_Local_Protected_Objects, Id);
3679 -- Protected objects with interrupt handlers must be at library level
3681 -- Ada 2005: This test is not needed (and the corresponding clause
3682 -- in the RM is removed) because accessibility checks are sufficient
3683 -- to make handlers not at the library level illegal.
3685 -- AI05-0303: The AI is in fact a binding interpretation, and thus
3686 -- applies to the '95 version of the language as well.
3688 if Is_Protected_Type (T)
3689 and then Has_Interrupt_Handler (T)
3690 and then Ada_Version < Ada_95
3693 ("interrupt object can only be declared at library level", Id);
3697 -- Check for violation of No_Local_Timing_Events
3699 if Has_Timing_Event (T) and then not Is_Library_Level_Entity (Id) then
3700 Check_Restriction (No_Local_Timing_Events, Id);
3703 -- The actual subtype of the object is the nominal subtype, unless
3704 -- the nominal one is unconstrained and obtained from the expression.
3708 -- These checks should be performed before the initialization expression
3709 -- is considered, so that the Object_Definition node is still the same
3710 -- as in source code.
3712 -- In SPARK, the nominal subtype is always given by a subtype mark
3713 -- and must not be unconstrained. (The only exception to this is the
3714 -- acceptance of declarations of constants of type String.)
3716 if not Nkind_In (Object_Definition (N), N_Expanded_Name, N_Identifier)
3718 Check_SPARK_05_Restriction
3719 ("subtype mark required", Object_Definition (N));
3721 elsif Is_Array_Type (T)
3722 and then not Is_Constrained (T)
3723 and then T /= Standard_String
3725 Check_SPARK_05_Restriction
3726 ("subtype mark of constrained type expected",
3727 Object_Definition (N));
3730 -- There are no aliased objects in SPARK
3732 if Aliased_Present (N) then
3733 Check_SPARK_05_Restriction ("aliased object is not allowed", N);
3736 -- Process initialization expression if present and not in error
3738 if Present (E) and then E /= Error then
3740 -- Generate an error in case of CPP class-wide object initialization.
3741 -- Required because otherwise the expansion of the class-wide
3742 -- assignment would try to use 'size to initialize the object
3743 -- (primitive that is not available in CPP tagged types).
3745 if Is_Class_Wide_Type (Act_T)
3747 (Is_CPP_Class (Root_Type (Etype (Act_T)))
3749 (Present (Full_View (Root_Type (Etype (Act_T))))
3751 Is_CPP_Class (Full_View (Root_Type (Etype (Act_T))))))
3754 ("predefined assignment not available for 'C'P'P tagged types",
3758 Mark_Coextensions (N, E);
3761 -- In case of errors detected in the analysis of the expression,
3762 -- decorate it with the expected type to avoid cascaded errors
3764 if No (Etype (E)) then
3768 -- If an initialization expression is present, then we set the
3769 -- Is_True_Constant flag. It will be reset if this is a variable
3770 -- and it is indeed modified.
3772 Set_Is_True_Constant (Id, True);
3774 -- If we are analyzing a constant declaration, set its completion
3775 -- flag after analyzing and resolving the expression.
3777 if Constant_Present (N) then
3778 Set_Has_Completion (Id);
3781 -- Set type and resolve (type may be overridden later on). Note:
3782 -- Ekind (Id) must still be E_Void at this point so that incorrect
3783 -- early usage within E is properly diagnosed.
3787 -- If the expression is an aggregate we must look ahead to detect
3788 -- the possible presence of an address clause, and defer resolution
3789 -- and expansion of the aggregate to the freeze point of the entity.
3791 -- This is not always legal because the aggregate may contain other
3792 -- references that need freezing, e.g. references to other entities
3793 -- with address clauses. In any case, when compiling with -gnatI the
3794 -- presence of the address clause must be ignored.
3796 if Comes_From_Source (N)
3797 and then Expander_Active
3798 and then Nkind (E) = N_Aggregate
3800 ((Present (Following_Address_Clause (N))
3801 and then not Ignore_Rep_Clauses)
3802 or else Delayed_Aspect_Present)
3810 -- No further action needed if E is a call to an inlined function
3811 -- which returns an unconstrained type and it has been expanded into
3812 -- a procedure call. In that case N has been replaced by an object
3813 -- declaration without initializing expression and it has been
3814 -- analyzed (see Expand_Inlined_Call).
3816 if Back_End_Inlining
3817 and then Expander_Active
3818 and then Nkind (E) = N_Function_Call
3819 and then Nkind (Name (E)) in N_Has_Entity
3820 and then Is_Inlined (Entity (Name (E)))
3821 and then not Is_Constrained (Etype (E))
3822 and then Analyzed (N)
3823 and then No (Expression (N))
3825 Ghost_Mode := Save_Ghost_Mode;
3829 -- If E is null and has been replaced by an N_Raise_Constraint_Error
3830 -- node (which was marked already-analyzed), we need to set the type
3831 -- to something other than Any_Access in order to keep gigi happy.
3833 if Etype (E) = Any_Access then
3837 -- If the object is an access to variable, the initialization
3838 -- expression cannot be an access to constant.
3840 if Is_Access_Type (T)
3841 and then not Is_Access_Constant (T)
3842 and then Is_Access_Type (Etype (E))
3843 and then Is_Access_Constant (Etype (E))
3846 ("access to variable cannot be initialized with an "
3847 & "access-to-constant expression", E);
3850 if not Assignment_OK (N) then
3851 Check_Initialization (T, E);
3854 Check_Unset_Reference (E);
3856 -- If this is a variable, then set current value. If this is a
3857 -- declared constant of a scalar type with a static expression,
3858 -- indicate that it is always valid.
3860 if not Constant_Present (N) then
3861 if Compile_Time_Known_Value (E) then
3862 Set_Current_Value (Id, E);
3865 elsif Is_Scalar_Type (T) and then Is_OK_Static_Expression (E) then
3866 Set_Is_Known_Valid (Id);
3869 -- Deal with setting of null flags
3871 if Is_Access_Type (T) then
3872 if Known_Non_Null (E) then
3873 Set_Is_Known_Non_Null (Id, True);
3874 elsif Known_Null (E) and then not Can_Never_Be_Null (Id) then
3875 Set_Is_Known_Null (Id, True);
3879 -- Check incorrect use of dynamically tagged expressions
3881 if Is_Tagged_Type (T) then
3882 Check_Dynamically_Tagged_Expression
3888 Apply_Scalar_Range_Check (E, T);
3889 Apply_Static_Length_Check (E, T);
3891 if Nkind (Original_Node (N)) = N_Object_Declaration
3892 and then Comes_From_Source (Original_Node (N))
3894 -- Only call test if needed
3896 and then Restriction_Check_Required (SPARK_05)
3897 and then not Is_SPARK_05_Initialization_Expr (Original_Node (E))
3899 Check_SPARK_05_Restriction
3900 ("initialization expression is not appropriate", E);
3903 -- A formal parameter of a specific tagged type whose related
3904 -- subprogram is subject to pragma Extensions_Visible with value
3905 -- "False" cannot be implicitly converted to a class-wide type by
3906 -- means of an initialization expression (SPARK RM 6.1.7(3)). Do
3907 -- not consider internally generated expressions.
3909 if Is_Class_Wide_Type (T)
3910 and then Comes_From_Source (E)
3911 and then Is_EVF_Expression (E)
3914 ("formal parameter cannot be implicitly converted to "
3915 & "class-wide type when Extensions_Visible is False", E);
3919 -- If the No_Streams restriction is set, check that the type of the
3920 -- object is not, and does not contain, any subtype derived from
3921 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
3922 -- Has_Stream just for efficiency reasons. There is no point in
3923 -- spending time on a Has_Stream check if the restriction is not set.
3925 if Restriction_Check_Required (No_Streams) then
3926 if Has_Stream (T) then
3927 Check_Restriction (No_Streams, N);
3931 -- Deal with predicate check before we start to do major rewriting. It
3932 -- is OK to initialize and then check the initialized value, since the
3933 -- object goes out of scope if we get a predicate failure. Note that we
3934 -- do this in the analyzer and not the expander because the analyzer
3935 -- does some substantial rewriting in some cases.
3937 -- We need a predicate check if the type has predicates that are not
3938 -- ignored, and if either there is an initializing expression, or for
3939 -- default initialization when we have at least one case of an explicit
3940 -- default initial value and then this is not an internal declaration
3941 -- whose initialization comes later (as for an aggregate expansion).
3943 if not Suppress_Assignment_Checks (N)
3944 and then Present (Predicate_Function (T))
3945 and then not Predicates_Ignored (T)
3946 and then not No_Initialization (N)
3950 Is_Partially_Initialized_Type (T, Include_Implicit => False))
3952 -- If the type has a static predicate and the expression is known at
3953 -- compile time, see if the expression satisfies the predicate.
3956 Check_Expression_Against_Static_Predicate (E, T);
3959 -- If the type is a null record and there is no explicit initial
3960 -- expression, no predicate check applies.
3962 if No (E) and then Is_Null_Record_Type (T) then
3967 Make_Predicate_Check (T, New_Occurrence_Of (Id, Loc)));
3971 -- Case of unconstrained type
3973 if not Is_Definite_Subtype (T) then
3975 -- In SPARK, a declaration of unconstrained type is allowed
3976 -- only for constants of type string.
3978 if Is_String_Type (T) and then not Constant_Present (N) then
3979 Check_SPARK_05_Restriction
3980 ("declaration of object of unconstrained type not allowed", N);
3983 -- Nothing to do in deferred constant case
3985 if Constant_Present (N) and then No (E) then
3988 -- Case of no initialization present
3991 if No_Initialization (N) then
3994 elsif Is_Class_Wide_Type (T) then
3996 ("initialization required in class-wide declaration ", N);
4000 ("unconstrained subtype not allowed (need initialization)",
4001 Object_Definition (N));
4003 if Is_Record_Type (T) and then Has_Discriminants (T) then
4005 ("\provide initial value or explicit discriminant values",
4006 Object_Definition (N));
4009 ("\or give default discriminant values for type&",
4010 Object_Definition (N), T);
4012 elsif Is_Array_Type (T) then
4014 ("\provide initial value or explicit array bounds",
4015 Object_Definition (N));
4019 -- Case of initialization present but in error. Set initial
4020 -- expression as absent (but do not make above complaints)
4022 elsif E = Error then
4023 Set_Expression (N, Empty);
4026 -- Case of initialization present
4029 -- Check restrictions in Ada 83
4031 if not Constant_Present (N) then
4033 -- Unconstrained variables not allowed in Ada 83 mode
4035 if Ada_Version = Ada_83
4036 and then Comes_From_Source (Object_Definition (N))
4039 ("(Ada 83) unconstrained variable not allowed",
4040 Object_Definition (N));
4044 -- Now we constrain the variable from the initializing expression
4046 -- If the expression is an aggregate, it has been expanded into
4047 -- individual assignments. Retrieve the actual type from the
4048 -- expanded construct.
4050 if Is_Array_Type (T)
4051 and then No_Initialization (N)
4052 and then Nkind (Original_Node (E)) = N_Aggregate
4056 -- In case of class-wide interface object declarations we delay
4057 -- the generation of the equivalent record type declarations until
4058 -- its expansion because there are cases in they are not required.
4060 elsif Is_Interface (T) then
4063 -- In GNATprove mode, Expand_Subtype_From_Expr does nothing. Thus,
4064 -- we should prevent the generation of another Itype with the
4065 -- same name as the one already generated, or we end up with
4066 -- two identical types in GNATprove.
4068 elsif GNATprove_Mode then
4071 -- If the type is an unchecked union, no subtype can be built from
4072 -- the expression. Rewrite declaration as a renaming, which the
4073 -- back-end can handle properly. This is a rather unusual case,
4074 -- because most unchecked_union declarations have default values
4075 -- for discriminants and are thus not indefinite.
4077 elsif Is_Unchecked_Union (T) then
4078 if Constant_Present (N) or else Nkind (E) = N_Function_Call then
4079 Set_Ekind (Id, E_Constant);
4081 Set_Ekind (Id, E_Variable);
4084 -- An object declared within a Ghost region is automatically
4085 -- Ghost (SPARK RM 6.9(2)).
4087 if Ghost_Mode > None then
4088 Set_Is_Ghost_Entity (Id);
4090 -- The Ghost policy in effect at the point of declaration
4091 -- and at the point of completion must match
4092 -- (SPARK RM 6.9(14)).
4094 if Present (Prev_Entity)
4095 and then Is_Ghost_Entity (Prev_Entity)
4097 Check_Ghost_Completion (Prev_Entity, Id);
4102 Make_Object_Renaming_Declaration (Loc,
4103 Defining_Identifier => Id,
4104 Subtype_Mark => New_Occurrence_Of (T, Loc),
4107 Set_Renamed_Object (Id, E);
4108 Freeze_Before (N, T);
4111 Ghost_Mode := Save_Ghost_Mode;
4115 -- Ensure that the generated subtype has a unique external name
4116 -- when the related object is public. This guarantees that the
4117 -- subtype and its bounds will not be affected by switches or
4118 -- pragmas that may offset the internal counter due to extra
4121 if Is_Public (Id) then
4124 Related_Id := Empty;
4127 Expand_Subtype_From_Expr
4130 Subtype_Indic => Object_Definition (N),
4132 Related_Id => Related_Id);
4134 Act_T := Find_Type_Of_Object (Object_Definition (N), N);
4137 Set_Is_Constr_Subt_For_U_Nominal (Act_T);
4139 if Aliased_Present (N) then
4140 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
4143 Freeze_Before (N, Act_T);
4144 Freeze_Before (N, T);
4147 elsif Is_Array_Type (T)
4148 and then No_Initialization (N)
4149 and then (Nkind (Original_Node (E)) = N_Aggregate
4150 or else (Nkind (Original_Node (E)) = N_Qualified_Expression
4151 and then Nkind (Original_Node (Expression
4152 (Original_Node (E)))) = N_Aggregate))
4154 if not Is_Entity_Name (Object_Definition (N)) then
4156 Check_Compile_Time_Size (Act_T);
4158 if Aliased_Present (N) then
4159 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
4163 -- When the given object definition and the aggregate are specified
4164 -- independently, and their lengths might differ do a length check.
4165 -- This cannot happen if the aggregate is of the form (others =>...)
4167 if not Is_Constrained (T) then
4170 elsif Nkind (E) = N_Raise_Constraint_Error then
4172 -- Aggregate is statically illegal. Place back in declaration
4174 Set_Expression (N, E);
4175 Set_No_Initialization (N, False);
4177 elsif T = Etype (E) then
4180 elsif Nkind (E) = N_Aggregate
4181 and then Present (Component_Associations (E))
4182 and then Present (Choices (First (Component_Associations (E))))
4183 and then Nkind (First
4184 (Choices (First (Component_Associations (E))))) = N_Others_Choice
4189 Apply_Length_Check (E, T);
4192 -- If the type is limited unconstrained with defaulted discriminants and
4193 -- there is no expression, then the object is constrained by the
4194 -- defaults, so it is worthwhile building the corresponding subtype.
4196 elsif (Is_Limited_Record (T) or else Is_Concurrent_Type (T))
4197 and then not Is_Constrained (T)
4198 and then Has_Discriminants (T)
4201 Act_T := Build_Default_Subtype (T, N);
4203 -- Ada 2005: A limited object may be initialized by means of an
4204 -- aggregate. If the type has default discriminants it has an
4205 -- unconstrained nominal type, Its actual subtype will be obtained
4206 -- from the aggregate, and not from the default discriminants.
4211 Rewrite (Object_Definition (N), New_Occurrence_Of (Act_T, Loc));
4213 elsif Nkind (E) = N_Function_Call
4214 and then Constant_Present (N)
4215 and then Has_Unconstrained_Elements (Etype (E))
4217 -- The back-end has problems with constants of a discriminated type
4218 -- with defaults, if the initial value is a function call. We
4219 -- generate an intermediate temporary that will receive a reference
4220 -- to the result of the call. The initialization expression then
4221 -- becomes a dereference of that temporary.
4223 Remove_Side_Effects (E);
4225 -- If this is a constant declaration of an unconstrained type and
4226 -- the initialization is an aggregate, we can use the subtype of the
4227 -- aggregate for the declared entity because it is immutable.
4229 elsif not Is_Constrained (T)
4230 and then Has_Discriminants (T)
4231 and then Constant_Present (N)
4232 and then not Has_Unchecked_Union (T)
4233 and then Nkind (E) = N_Aggregate
4238 -- Check No_Wide_Characters restriction
4240 Check_Wide_Character_Restriction (T, Object_Definition (N));
4242 -- Indicate this is not set in source. Certainly true for constants, and
4243 -- true for variables so far (will be reset for a variable if and when
4244 -- we encounter a modification in the source).
4246 Set_Never_Set_In_Source (Id);
4248 -- Now establish the proper kind and type of the object
4250 if Constant_Present (N) then
4251 Set_Ekind (Id, E_Constant);
4252 Set_Is_True_Constant (Id);
4255 Set_Ekind (Id, E_Variable);
4257 -- A variable is set as shared passive if it appears in a shared
4258 -- passive package, and is at the outer level. This is not done for
4259 -- entities generated during expansion, because those are always
4260 -- manipulated locally.
4262 if Is_Shared_Passive (Current_Scope)
4263 and then Is_Library_Level_Entity (Id)
4264 and then Comes_From_Source (Id)
4266 Set_Is_Shared_Passive (Id);
4267 Check_Shared_Var (Id, T, N);
4270 -- Set Has_Initial_Value if initializing expression present. Note
4271 -- that if there is no initializing expression, we leave the state
4272 -- of this flag unchanged (usually it will be False, but notably in
4273 -- the case of exception choice variables, it will already be true).
4276 Set_Has_Initial_Value (Id);
4280 -- Initialize alignment and size and capture alignment setting
4282 Init_Alignment (Id);
4284 Set_Optimize_Alignment_Flags (Id);
4286 -- An object declared within a Ghost region is automatically Ghost
4287 -- (SPARK RM 6.9(2)).
4289 if Ghost_Mode > None
4290 or else (Present (Prev_Entity) and then Is_Ghost_Entity (Prev_Entity))
4292 Set_Is_Ghost_Entity (Id);
4294 -- The Ghost policy in effect at the point of declaration and at the
4295 -- point of completion must match (SPARK RM 6.9(14)).
4297 if Present (Prev_Entity) and then Is_Ghost_Entity (Prev_Entity) then
4298 Check_Ghost_Completion (Prev_Entity, Id);
4302 -- Deal with aliased case
4304 if Aliased_Present (N) then
4305 Set_Is_Aliased (Id);
4307 -- If the object is aliased and the type is unconstrained with
4308 -- defaulted discriminants and there is no expression, then the
4309 -- object is constrained by the defaults, so it is worthwhile
4310 -- building the corresponding subtype.
4312 -- Ada 2005 (AI-363): If the aliased object is discriminated and
4313 -- unconstrained, then only establish an actual subtype if the
4314 -- nominal subtype is indefinite. In definite cases the object is
4315 -- unconstrained in Ada 2005.
4318 and then Is_Record_Type (T)
4319 and then not Is_Constrained (T)
4320 and then Has_Discriminants (T)
4321 and then (Ada_Version < Ada_2005
4322 or else not Is_Definite_Subtype (T))
4324 Set_Actual_Subtype (Id, Build_Default_Subtype (T, N));
4328 -- Now we can set the type of the object
4330 Set_Etype (Id, Act_T);
4332 -- Non-constant object is marked to be treated as volatile if type is
4333 -- volatile and we clear the Current_Value setting that may have been
4334 -- set above. Doing so for constants isn't required and might interfere
4335 -- with possible uses of the object as a static expression in contexts
4336 -- incompatible with volatility (e.g. as a case-statement alternative).
4338 if Ekind (Id) /= E_Constant and then Treat_As_Volatile (Etype (Id)) then
4339 Set_Treat_As_Volatile (Id);
4340 Set_Current_Value (Id, Empty);
4343 -- Deal with controlled types
4345 if Has_Controlled_Component (Etype (Id))
4346 or else Is_Controlled (Etype (Id))
4348 if not Is_Library_Level_Entity (Id) then
4349 Check_Restriction (No_Nested_Finalization, N);
4351 Validate_Controlled_Object (Id);
4355 if Has_Task (Etype (Id)) then
4356 Check_Restriction (No_Tasking, N);
4358 -- Deal with counting max tasks
4360 -- Nothing to do if inside a generic
4362 if Inside_A_Generic then
4365 -- If library level entity, then count tasks
4367 elsif Is_Library_Level_Entity (Id) then
4368 Check_Restriction (Max_Tasks, N, Count_Tasks (Etype (Id)));
4370 -- If not library level entity, then indicate we don't know max
4371 -- tasks and also check task hierarchy restriction and blocking
4372 -- operation (since starting a task is definitely blocking).
4375 Check_Restriction (Max_Tasks, N);
4376 Check_Restriction (No_Task_Hierarchy, N);
4377 Check_Potentially_Blocking_Operation (N);
4380 -- A rather specialized test. If we see two tasks being declared
4381 -- of the same type in the same object declaration, and the task
4382 -- has an entry with an address clause, we know that program error
4383 -- will be raised at run time since we can't have two tasks with
4384 -- entries at the same address.
4386 if Is_Task_Type (Etype (Id)) and then More_Ids (N) then
4391 E := First_Entity (Etype (Id));
4392 while Present (E) loop
4393 if Ekind (E) = E_Entry
4394 and then Present (Get_Attribute_Definition_Clause
4395 (E, Attribute_Address))
4397 Error_Msg_Warn := SPARK_Mode /= On;
4399 ("more than one task with same entry address<<", N);
4400 Error_Msg_N ("\Program_Error [<<", N);
4402 Make_Raise_Program_Error (Loc,
4403 Reason => PE_Duplicated_Entry_Address));
4413 -- Some simple constant-propagation: if the expression is a constant
4414 -- string initialized with a literal, share the literal. This avoids
4418 and then Is_Entity_Name (E)
4419 and then Ekind (Entity (E)) = E_Constant
4420 and then Base_Type (Etype (E)) = Standard_String
4423 Val : constant Node_Id := Constant_Value (Entity (E));
4425 if Present (Val) and then Nkind (Val) = N_String_Literal then
4426 Rewrite (E, New_Copy (Val));
4431 -- Another optimization: if the nominal subtype is unconstrained and
4432 -- the expression is a function call that returns an unconstrained
4433 -- type, rewrite the declaration as a renaming of the result of the
4434 -- call. The exceptions below are cases where the copy is expected,
4435 -- either by the back end (Aliased case) or by the semantics, as for
4436 -- initializing controlled types or copying tags for class-wide types.
4439 and then Nkind (E) = N_Explicit_Dereference
4440 and then Nkind (Original_Node (E)) = N_Function_Call
4441 and then not Is_Library_Level_Entity (Id)
4442 and then not Is_Constrained (Underlying_Type (T))
4443 and then not Is_Aliased (Id)
4444 and then not Is_Class_Wide_Type (T)
4445 and then not Is_Controlled_Active (T)
4446 and then not Has_Controlled_Component (Base_Type (T))
4447 and then Expander_Active
4450 Make_Object_Renaming_Declaration (Loc,
4451 Defining_Identifier => Id,
4452 Access_Definition => Empty,
4453 Subtype_Mark => New_Occurrence_Of
4454 (Base_Type (Etype (Id)), Loc),
4457 Set_Renamed_Object (Id, E);
4459 -- Force generation of debugging information for the constant and for
4460 -- the renamed function call.
4462 Set_Debug_Info_Needed (Id);
4463 Set_Debug_Info_Needed (Entity (Prefix (E)));
4466 if Present (Prev_Entity)
4467 and then Is_Frozen (Prev_Entity)
4468 and then not Error_Posted (Id)
4470 Error_Msg_N ("full constant declaration appears too late", N);
4473 Check_Eliminated (Id);
4475 -- Deal with setting In_Private_Part flag if in private part
4477 if Ekind (Scope (Id)) = E_Package
4478 and then In_Private_Part (Scope (Id))
4480 Set_In_Private_Part (Id);
4484 -- Initialize the refined state of a variable here because this is a
4485 -- common destination for legal and illegal object declarations.
4487 if Ekind (Id) = E_Variable then
4488 Set_Encapsulating_State (Id, Empty);
4491 if Has_Aspects (N) then
4492 Analyze_Aspect_Specifications (N, Id);
4495 Analyze_Dimension (N);
4497 -- Verify whether the object declaration introduces an illegal hidden
4498 -- state within a package subject to a null abstract state.
4500 if Ekind (Id) = E_Variable then
4501 Check_No_Hidden_State (Id);
4504 Ghost_Mode := Save_Ghost_Mode;
4505 end Analyze_Object_Declaration;
4507 ---------------------------
4508 -- Analyze_Others_Choice --
4509 ---------------------------
4511 -- Nothing to do for the others choice node itself, the semantic analysis
4512 -- of the others choice will occur as part of the processing of the parent
4514 procedure Analyze_Others_Choice (N : Node_Id) is
4515 pragma Warnings (Off, N);
4518 end Analyze_Others_Choice;
4520 -------------------------------------------
4521 -- Analyze_Private_Extension_Declaration --
4522 -------------------------------------------
4524 procedure Analyze_Private_Extension_Declaration (N : Node_Id) is
4525 Indic : constant Node_Id := Subtype_Indication (N);
4526 T : constant Entity_Id := Defining_Identifier (N);
4528 Iface_Elmt : Elmt_Id;
4529 Parent_Base : Entity_Id;
4530 Parent_Type : Entity_Id;
4533 -- Ada 2005 (AI-251): Decorate all names in list of ancestor interfaces
4535 if Is_Non_Empty_List (Interface_List (N)) then
4541 Intf := First (Interface_List (N));
4542 while Present (Intf) loop
4543 T := Find_Type_Of_Subtype_Indic (Intf);
4545 Diagnose_Interface (Intf, T);
4551 Generate_Definition (T);
4553 -- For other than Ada 2012, just enter the name in the current scope
4555 if Ada_Version < Ada_2012 then
4558 -- Ada 2012 (AI05-0162): Enter the name in the current scope handling
4559 -- case of private type that completes an incomplete type.
4566 Prev := Find_Type_Name (N);
4568 pragma Assert (Prev = T
4569 or else (Ekind (Prev) = E_Incomplete_Type
4570 and then Present (Full_View (Prev))
4571 and then Full_View (Prev) = T));
4575 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
4576 Parent_Base := Base_Type (Parent_Type);
4578 if Parent_Type = Any_Type or else Etype (Parent_Type) = Any_Type then
4579 Set_Ekind (T, Ekind (Parent_Type));
4580 Set_Etype (T, Any_Type);
4583 elsif not Is_Tagged_Type (Parent_Type) then
4585 ("parent of type extension must be a tagged type ", Indic);
4588 elsif Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
4589 Error_Msg_N ("premature derivation of incomplete type", Indic);
4592 elsif Is_Concurrent_Type (Parent_Type) then
4594 ("parent type of a private extension cannot be a synchronized "
4595 & "tagged type (RM 3.9.1 (3/1))", N);
4597 Set_Etype (T, Any_Type);
4598 Set_Ekind (T, E_Limited_Private_Type);
4599 Set_Private_Dependents (T, New_Elmt_List);
4600 Set_Error_Posted (T);
4604 -- Perhaps the parent type should be changed to the class-wide type's
4605 -- specific type in this case to prevent cascading errors ???
4607 if Is_Class_Wide_Type (Parent_Type) then
4609 ("parent of type extension must not be a class-wide type", Indic);
4613 if (not Is_Package_Or_Generic_Package (Current_Scope)
4614 and then Nkind (Parent (N)) /= N_Generic_Subprogram_Declaration)
4615 or else In_Private_Part (Current_Scope)
4617 Error_Msg_N ("invalid context for private extension", N);
4620 -- Set common attributes
4622 Set_Is_Pure (T, Is_Pure (Current_Scope));
4623 Set_Scope (T, Current_Scope);
4624 Set_Ekind (T, E_Record_Type_With_Private);
4625 Init_Size_Align (T);
4626 Set_Default_SSO (T);
4628 Set_Etype (T, Parent_Base);
4629 Propagate_Concurrent_Flags (T, Parent_Base);
4631 Set_Convention (T, Convention (Parent_Type));
4632 Set_First_Rep_Item (T, First_Rep_Item (Parent_Type));
4633 Set_Is_First_Subtype (T);
4634 Make_Class_Wide_Type (T);
4636 if Unknown_Discriminants_Present (N) then
4637 Set_Discriminant_Constraint (T, No_Elist);
4640 Build_Derived_Record_Type (N, Parent_Type, T);
4642 -- A private extension inherits any class-wide invariants coming from a
4643 -- parent type or an interface. Note that the invariant procedure of the
4644 -- parent type should not be inherited because the private extension may
4645 -- define invariants of its own.
4647 if Has_Inheritable_Invariants (Parent_Type) then
4648 Set_Has_Inherited_Invariants (T);
4650 elsif Present (Interfaces (T)) then
4651 Iface_Elmt := First_Elmt (Interfaces (T));
4652 while Present (Iface_Elmt) loop
4653 Iface := Node (Iface_Elmt);
4655 if Has_Inheritable_Invariants (Iface) then
4656 Set_Has_Inherited_Invariants (T);
4660 Next_Elmt (Iface_Elmt);
4664 -- Ada 2005 (AI-443): Synchronized private extension or a rewritten
4665 -- synchronized formal derived type.
4667 if Ada_Version >= Ada_2005 and then Synchronized_Present (N) then
4668 Set_Is_Limited_Record (T);
4670 -- Formal derived type case
4672 if Is_Generic_Type (T) then
4674 -- The parent must be a tagged limited type or a synchronized
4677 if (not Is_Tagged_Type (Parent_Type)
4678 or else not Is_Limited_Type (Parent_Type))
4680 (not Is_Interface (Parent_Type)
4681 or else not Is_Synchronized_Interface (Parent_Type))
4684 ("parent type of & must be tagged limited or synchronized",
4688 -- The progenitors (if any) must be limited or synchronized
4691 if Present (Interfaces (T)) then
4692 Iface_Elmt := First_Elmt (Interfaces (T));
4693 while Present (Iface_Elmt) loop
4694 Iface := Node (Iface_Elmt);
4696 if not Is_Limited_Interface (Iface)
4697 and then not Is_Synchronized_Interface (Iface)
4700 ("progenitor & must be limited or synchronized",
4704 Next_Elmt (Iface_Elmt);
4708 -- Regular derived extension, the parent must be a limited or
4709 -- synchronized interface.
4712 if not Is_Interface (Parent_Type)
4713 or else (not Is_Limited_Interface (Parent_Type)
4714 and then not Is_Synchronized_Interface (Parent_Type))
4717 ("parent type of & must be limited interface", N, T);
4721 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
4722 -- extension with a synchronized parent must be explicitly declared
4723 -- synchronized, because the full view will be a synchronized type.
4724 -- This must be checked before the check for limited types below,
4725 -- to ensure that types declared limited are not allowed to extend
4726 -- synchronized interfaces.
4728 elsif Is_Interface (Parent_Type)
4729 and then Is_Synchronized_Interface (Parent_Type)
4730 and then not Synchronized_Present (N)
4733 ("private extension of& must be explicitly synchronized",
4736 elsif Limited_Present (N) then
4737 Set_Is_Limited_Record (T);
4739 if not Is_Limited_Type (Parent_Type)
4741 (not Is_Interface (Parent_Type)
4742 or else not Is_Limited_Interface (Parent_Type))
4744 Error_Msg_NE ("parent type& of limited extension must be limited",
4750 if Has_Aspects (N) then
4751 Analyze_Aspect_Specifications (N, T);
4753 end Analyze_Private_Extension_Declaration;
4755 ---------------------------------
4756 -- Analyze_Subtype_Declaration --
4757 ---------------------------------
4759 procedure Analyze_Subtype_Declaration
4761 Skip : Boolean := False)
4763 Id : constant Entity_Id := Defining_Identifier (N);
4764 R_Checks : Check_Result;
4768 Generate_Definition (Id);
4769 Set_Is_Pure (Id, Is_Pure (Current_Scope));
4770 Init_Size_Align (Id);
4772 -- The following guard condition on Enter_Name is to handle cases where
4773 -- the defining identifier has already been entered into the scope but
4774 -- the declaration as a whole needs to be analyzed.
4776 -- This case in particular happens for derived enumeration types. The
4777 -- derived enumeration type is processed as an inserted enumeration type
4778 -- declaration followed by a rewritten subtype declaration. The defining
4779 -- identifier, however, is entered into the name scope very early in the
4780 -- processing of the original type declaration and therefore needs to be
4781 -- avoided here, when the created subtype declaration is analyzed. (See
4782 -- Build_Derived_Types)
4784 -- This also happens when the full view of a private type is derived
4785 -- type with constraints. In this case the entity has been introduced
4786 -- in the private declaration.
4788 -- Finally this happens in some complex cases when validity checks are
4789 -- enabled, where the same subtype declaration may be analyzed twice.
4790 -- This can happen if the subtype is created by the pre-analysis of
4791 -- an attribute tht gives the range of a loop statement, and the loop
4792 -- itself appears within an if_statement that will be rewritten during
4796 or else (Present (Etype (Id))
4797 and then (Is_Private_Type (Etype (Id))
4798 or else Is_Task_Type (Etype (Id))
4799 or else Is_Rewrite_Substitution (N)))
4803 elsif Current_Entity (Id) = Id then
4810 T := Process_Subtype (Subtype_Indication (N), N, Id, 'P');
4812 -- Class-wide equivalent types of records with unknown discriminants
4813 -- involve the generation of an itype which serves as the private view
4814 -- of a constrained record subtype. In such cases the base type of the
4815 -- current subtype we are processing is the private itype. Use the full
4816 -- of the private itype when decorating various attributes.
4819 and then Is_Private_Type (T)
4820 and then Present (Full_View (T))
4825 -- Inherit common attributes
4827 Set_Is_Volatile (Id, Is_Volatile (T));
4828 Set_Treat_As_Volatile (Id, Treat_As_Volatile (T));
4829 Set_Is_Generic_Type (Id, Is_Generic_Type (Base_Type (T)));
4830 Set_Convention (Id, Convention (T));
4832 -- If ancestor has predicates then so does the subtype, and in addition
4833 -- we must delay the freeze to properly arrange predicate inheritance.
4835 -- The Ancestor_Type test is really unpleasant, there seem to be cases
4836 -- in which T = ID, so the above tests and assignments do nothing???
4838 if Has_Predicates (T)
4839 or else (Present (Ancestor_Subtype (T))
4840 and then Has_Predicates (Ancestor_Subtype (T)))
4842 Set_Has_Predicates (Id);
4843 Set_Has_Delayed_Freeze (Id);
4845 -- Generated subtypes inherit the predicate function from the parent
4846 -- (no aspects to examine on the generated declaration).
4848 if not Comes_From_Source (N) then
4849 Set_Ekind (Id, Ekind (T));
4851 if Present (Predicate_Function (T)) then
4852 Set_Predicate_Function (Id, Predicate_Function (T));
4854 elsif Present (Ancestor_Subtype (T))
4855 and then Has_Predicates (Ancestor_Subtype (T))
4856 and then Present (Predicate_Function (Ancestor_Subtype (T)))
4858 Set_Predicate_Function (Id,
4859 Predicate_Function (Ancestor_Subtype (T)));
4864 -- Subtype of Boolean cannot have a constraint in SPARK
4866 if Is_Boolean_Type (T)
4867 and then Nkind (Subtype_Indication (N)) = N_Subtype_Indication
4869 Check_SPARK_05_Restriction
4870 ("subtype of Boolean cannot have constraint", N);
4873 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4875 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
4881 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint then
4882 One_Cstr := First (Constraints (Cstr));
4883 while Present (One_Cstr) loop
4885 -- Index or discriminant constraint in SPARK must be a
4889 Nkind_In (One_Cstr, N_Identifier, N_Expanded_Name)
4891 Check_SPARK_05_Restriction
4892 ("subtype mark required", One_Cstr);
4894 -- String subtype must have a lower bound of 1 in SPARK.
4895 -- Note that we do not need to test for the non-static case
4896 -- here, since that was already taken care of in
4897 -- Process_Range_Expr_In_Decl.
4899 elsif Base_Type (T) = Standard_String then
4900 Get_Index_Bounds (One_Cstr, Low, High);
4902 if Is_OK_Static_Expression (Low)
4903 and then Expr_Value (Low) /= 1
4905 Check_SPARK_05_Restriction
4906 ("String subtype must have lower bound of 1", N);
4916 -- In the case where there is no constraint given in the subtype
4917 -- indication, Process_Subtype just returns the Subtype_Mark, so its
4918 -- semantic attributes must be established here.
4920 if Nkind (Subtype_Indication (N)) /= N_Subtype_Indication then
4921 Set_Etype (Id, Base_Type (T));
4923 -- Subtype of unconstrained array without constraint is not allowed
4926 if Is_Array_Type (T) and then not Is_Constrained (T) then
4927 Check_SPARK_05_Restriction
4928 ("subtype of unconstrained array must have constraint", N);
4933 Set_Ekind (Id, E_Array_Subtype);
4934 Copy_Array_Subtype_Attributes (Id, T);
4936 when Decimal_Fixed_Point_Kind =>
4937 Set_Ekind (Id, E_Decimal_Fixed_Point_Subtype);
4938 Set_Digits_Value (Id, Digits_Value (T));
4939 Set_Delta_Value (Id, Delta_Value (T));
4940 Set_Scale_Value (Id, Scale_Value (T));
4941 Set_Small_Value (Id, Small_Value (T));
4942 Set_Scalar_Range (Id, Scalar_Range (T));
4943 Set_Machine_Radix_10 (Id, Machine_Radix_10 (T));
4944 Set_Is_Constrained (Id, Is_Constrained (T));
4945 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4946 Set_RM_Size (Id, RM_Size (T));
4948 when Enumeration_Kind =>
4949 Set_Ekind (Id, E_Enumeration_Subtype);
4950 Set_First_Literal (Id, First_Literal (Base_Type (T)));
4951 Set_Scalar_Range (Id, Scalar_Range (T));
4952 Set_Is_Character_Type (Id, Is_Character_Type (T));
4953 Set_Is_Constrained (Id, Is_Constrained (T));
4954 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4955 Set_RM_Size (Id, RM_Size (T));
4956 Inherit_Predicate_Flags (Id, T);
4958 when Ordinary_Fixed_Point_Kind =>
4959 Set_Ekind (Id, E_Ordinary_Fixed_Point_Subtype);
4960 Set_Scalar_Range (Id, Scalar_Range (T));
4961 Set_Small_Value (Id, Small_Value (T));
4962 Set_Delta_Value (Id, Delta_Value (T));
4963 Set_Is_Constrained (Id, Is_Constrained (T));
4964 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4965 Set_RM_Size (Id, RM_Size (T));
4968 Set_Ekind (Id, E_Floating_Point_Subtype);
4969 Set_Scalar_Range (Id, Scalar_Range (T));
4970 Set_Digits_Value (Id, Digits_Value (T));
4971 Set_Is_Constrained (Id, Is_Constrained (T));
4973 -- If the floating point type has dimensions, these will be
4974 -- inherited subsequently when Analyze_Dimensions is called.
4976 when Signed_Integer_Kind =>
4977 Set_Ekind (Id, E_Signed_Integer_Subtype);
4978 Set_Scalar_Range (Id, Scalar_Range (T));
4979 Set_Is_Constrained (Id, Is_Constrained (T));
4980 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4981 Set_RM_Size (Id, RM_Size (T));
4982 Inherit_Predicate_Flags (Id, T);
4984 when Modular_Integer_Kind =>
4985 Set_Ekind (Id, E_Modular_Integer_Subtype);
4986 Set_Scalar_Range (Id, Scalar_Range (T));
4987 Set_Is_Constrained (Id, Is_Constrained (T));
4988 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4989 Set_RM_Size (Id, RM_Size (T));
4990 Inherit_Predicate_Flags (Id, T);
4992 when Class_Wide_Kind =>
4993 Set_Ekind (Id, E_Class_Wide_Subtype);
4994 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4995 Set_Cloned_Subtype (Id, T);
4996 Set_Is_Tagged_Type (Id, True);
4997 Set_Has_Unknown_Discriminants
4999 Set_No_Tagged_Streams_Pragma
5000 (Id, No_Tagged_Streams_Pragma (T));
5002 if Ekind (T) = E_Class_Wide_Subtype then
5003 Set_Equivalent_Type (Id, Equivalent_Type (T));
5006 when E_Record_Type | E_Record_Subtype =>
5007 Set_Ekind (Id, E_Record_Subtype);
5009 if Ekind (T) = E_Record_Subtype
5010 and then Present (Cloned_Subtype (T))
5012 Set_Cloned_Subtype (Id, Cloned_Subtype (T));
5014 Set_Cloned_Subtype (Id, T);
5017 Set_First_Entity (Id, First_Entity (T));
5018 Set_Last_Entity (Id, Last_Entity (T));
5019 Set_Has_Discriminants (Id, Has_Discriminants (T));
5020 Set_Is_Constrained (Id, Is_Constrained (T));
5021 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
5022 Set_Has_Implicit_Dereference
5023 (Id, Has_Implicit_Dereference (T));
5024 Set_Has_Unknown_Discriminants
5025 (Id, Has_Unknown_Discriminants (T));
5027 if Has_Discriminants (T) then
5028 Set_Discriminant_Constraint
5029 (Id, Discriminant_Constraint (T));
5030 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5032 elsif Has_Unknown_Discriminants (Id) then
5033 Set_Discriminant_Constraint (Id, No_Elist);
5036 if Is_Tagged_Type (T) then
5037 Set_Is_Tagged_Type (Id, True);
5038 Set_No_Tagged_Streams_Pragma
5039 (Id, No_Tagged_Streams_Pragma (T));
5040 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
5041 Set_Direct_Primitive_Operations
5042 (Id, Direct_Primitive_Operations (T));
5043 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
5045 if Is_Interface (T) then
5046 Set_Is_Interface (Id);
5047 Set_Is_Limited_Interface (Id, Is_Limited_Interface (T));
5051 when Private_Kind =>
5052 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
5053 Set_Has_Discriminants (Id, Has_Discriminants (T));
5054 Set_Is_Constrained (Id, Is_Constrained (T));
5055 Set_First_Entity (Id, First_Entity (T));
5056 Set_Last_Entity (Id, Last_Entity (T));
5057 Set_Private_Dependents (Id, New_Elmt_List);
5058 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
5059 Set_Has_Implicit_Dereference
5060 (Id, Has_Implicit_Dereference (T));
5061 Set_Has_Unknown_Discriminants
5062 (Id, Has_Unknown_Discriminants (T));
5063 Set_Known_To_Have_Preelab_Init
5064 (Id, Known_To_Have_Preelab_Init (T));
5066 if Is_Tagged_Type (T) then
5067 Set_Is_Tagged_Type (Id);
5068 Set_No_Tagged_Streams_Pragma (Id,
5069 No_Tagged_Streams_Pragma (T));
5070 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
5071 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
5072 Set_Direct_Primitive_Operations (Id,
5073 Direct_Primitive_Operations (T));
5076 -- In general the attributes of the subtype of a private type
5077 -- are the attributes of the partial view of parent. However,
5078 -- the full view may be a discriminated type, and the subtype
5079 -- must share the discriminant constraint to generate correct
5080 -- calls to initialization procedures.
5082 if Has_Discriminants (T) then
5083 Set_Discriminant_Constraint
5084 (Id, Discriminant_Constraint (T));
5085 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5087 elsif Present (Full_View (T))
5088 and then Has_Discriminants (Full_View (T))
5090 Set_Discriminant_Constraint
5091 (Id, Discriminant_Constraint (Full_View (T)));
5092 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5094 -- This would seem semantically correct, but apparently
5095 -- generates spurious errors about missing components ???
5097 -- Set_Has_Discriminants (Id);
5100 Prepare_Private_Subtype_Completion (Id, N);
5102 -- If this is the subtype of a constrained private type with
5103 -- discriminants that has got a full view and we also have
5104 -- built a completion just above, show that the completion
5105 -- is a clone of the full view to the back-end.
5107 if Has_Discriminants (T)
5108 and then not Has_Unknown_Discriminants (T)
5109 and then not Is_Empty_Elmt_List (Discriminant_Constraint (T))
5110 and then Present (Full_View (T))
5111 and then Present (Full_View (Id))
5113 Set_Cloned_Subtype (Full_View (Id), Full_View (T));
5117 Set_Ekind (Id, E_Access_Subtype);
5118 Set_Is_Constrained (Id, Is_Constrained (T));
5119 Set_Is_Access_Constant
5120 (Id, Is_Access_Constant (T));
5121 Set_Directly_Designated_Type
5122 (Id, Designated_Type (T));
5123 Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T));
5125 -- A Pure library_item must not contain the declaration of a
5126 -- named access type, except within a subprogram, generic
5127 -- subprogram, task unit, or protected unit, or if it has
5128 -- a specified Storage_Size of zero (RM05-10.2.1(15.4-15.5)).
5130 if Comes_From_Source (Id)
5131 and then In_Pure_Unit
5132 and then not In_Subprogram_Task_Protected_Unit
5133 and then not No_Pool_Assigned (Id)
5136 ("named access types not allowed in pure unit", N);
5139 when Concurrent_Kind =>
5140 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
5141 Set_Corresponding_Record_Type (Id,
5142 Corresponding_Record_Type (T));
5143 Set_First_Entity (Id, First_Entity (T));
5144 Set_First_Private_Entity (Id, First_Private_Entity (T));
5145 Set_Has_Discriminants (Id, Has_Discriminants (T));
5146 Set_Is_Constrained (Id, Is_Constrained (T));
5147 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
5148 Set_Last_Entity (Id, Last_Entity (T));
5150 if Is_Tagged_Type (T) then
5151 Set_No_Tagged_Streams_Pragma
5152 (Id, No_Tagged_Streams_Pragma (T));
5155 if Has_Discriminants (T) then
5156 Set_Discriminant_Constraint
5157 (Id, Discriminant_Constraint (T));
5158 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5161 when Incomplete_Kind =>
5162 if Ada_Version >= Ada_2005 then
5164 -- In Ada 2005 an incomplete type can be explicitly tagged:
5165 -- propagate indication. Note that we also have to include
5166 -- subtypes for Ada 2012 extended use of incomplete types.
5168 Set_Ekind (Id, E_Incomplete_Subtype);
5169 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
5170 Set_Private_Dependents (Id, New_Elmt_List);
5172 if Is_Tagged_Type (Id) then
5173 Set_No_Tagged_Streams_Pragma
5174 (Id, No_Tagged_Streams_Pragma (T));
5175 Set_Direct_Primitive_Operations (Id, New_Elmt_List);
5178 -- Ada 2005 (AI-412): Decorate an incomplete subtype of an
5179 -- incomplete type visible through a limited with clause.
5181 if From_Limited_With (T)
5182 and then Present (Non_Limited_View (T))
5184 Set_From_Limited_With (Id);
5185 Set_Non_Limited_View (Id, Non_Limited_View (T));
5187 -- Ada 2005 (AI-412): Add the regular incomplete subtype
5188 -- to the private dependents of the original incomplete
5189 -- type for future transformation.
5192 Append_Elmt (Id, Private_Dependents (T));
5195 -- If the subtype name denotes an incomplete type an error
5196 -- was already reported by Process_Subtype.
5199 Set_Etype (Id, Any_Type);
5203 raise Program_Error;
5207 if Etype (Id) = Any_Type then
5211 -- Some common processing on all types
5213 Set_Size_Info (Id, T);
5214 Set_First_Rep_Item (Id, First_Rep_Item (T));
5216 -- If the parent type is a generic actual, so is the subtype. This may
5217 -- happen in a nested instance. Why Comes_From_Source test???
5219 if not Comes_From_Source (N) then
5220 Set_Is_Generic_Actual_Type (Id, Is_Generic_Actual_Type (T));
5223 -- If this is a subtype declaration for an actual in an instance,
5224 -- inherit static and dynamic predicates if any.
5226 -- If declaration has no aspect specifications, inherit predicate
5227 -- info as well. Unclear how to handle the case of both specified
5228 -- and inherited predicates ??? Other inherited aspects, such as
5229 -- invariants, should be OK, but the combination with later pragmas
5230 -- may also require special merging.
5232 if Has_Predicates (T)
5233 and then Present (Predicate_Function (T))
5235 ((In_Instance and then not Comes_From_Source (N))
5236 or else No (Aspect_Specifications (N)))
5238 Set_Subprograms_For_Type (Id, Subprograms_For_Type (T));
5240 if Has_Static_Predicate (T) then
5241 Set_Has_Static_Predicate (Id);
5242 Set_Static_Discrete_Predicate (Id, Static_Discrete_Predicate (T));
5246 -- Propagate invariant-related attributes from the base type to the
5249 Propagate_Invariant_Attributes (Id, From_Typ => Base_Type (T));
5251 -- Remaining processing depends on characteristics of base type
5255 Set_Is_Immediately_Visible (Id, True);
5256 Set_Depends_On_Private (Id, Has_Private_Component (T));
5257 Set_Is_Descendant_Of_Address (Id, Is_Descendant_Of_Address (T));
5259 if Is_Interface (T) then
5260 Set_Is_Interface (Id);
5263 if Present (Generic_Parent_Type (N))
5265 (Nkind (Parent (Generic_Parent_Type (N))) /=
5266 N_Formal_Type_Declaration
5267 or else Nkind (Formal_Type_Definition
5268 (Parent (Generic_Parent_Type (N)))) /=
5269 N_Formal_Private_Type_Definition)
5271 if Is_Tagged_Type (Id) then
5273 -- If this is a generic actual subtype for a synchronized type,
5274 -- the primitive operations are those of the corresponding record
5275 -- for which there is a separate subtype declaration.
5277 if Is_Concurrent_Type (Id) then
5279 elsif Is_Class_Wide_Type (Id) then
5280 Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T));
5282 Derive_Subprograms (Generic_Parent_Type (N), Id, T);
5285 elsif Scope (Etype (Id)) /= Standard_Standard then
5286 Derive_Subprograms (Generic_Parent_Type (N), Id);
5290 if Is_Private_Type (T) and then Present (Full_View (T)) then
5291 Conditional_Delay (Id, Full_View (T));
5293 -- The subtypes of components or subcomponents of protected types
5294 -- do not need freeze nodes, which would otherwise appear in the
5295 -- wrong scope (before the freeze node for the protected type). The
5296 -- proper subtypes are those of the subcomponents of the corresponding
5299 elsif Ekind (Scope (Id)) /= E_Protected_Type
5300 and then Present (Scope (Scope (Id))) -- error defense
5301 and then Ekind (Scope (Scope (Id))) /= E_Protected_Type
5303 Conditional_Delay (Id, T);
5306 -- Check that Constraint_Error is raised for a scalar subtype indication
5307 -- when the lower or upper bound of a non-null range lies outside the
5308 -- range of the type mark.
5310 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5311 if Is_Scalar_Type (Etype (Id))
5312 and then Scalar_Range (Id) /=
5314 (Etype (Subtype_Mark (Subtype_Indication (N))))
5318 Etype (Subtype_Mark (Subtype_Indication (N))));
5320 -- In the array case, check compatibility for each index
5322 elsif Is_Array_Type (Etype (Id)) and then Present (First_Index (Id))
5324 -- This really should be a subprogram that finds the indications
5328 Subt_Index : Node_Id := First_Index (Id);
5329 Target_Index : Node_Id :=
5331 (Subtype_Mark (Subtype_Indication (N))));
5332 Has_Dyn_Chk : Boolean := Has_Dynamic_Range_Check (N);
5335 while Present (Subt_Index) loop
5336 if ((Nkind (Subt_Index) = N_Identifier
5337 and then Ekind (Entity (Subt_Index)) in Scalar_Kind)
5338 or else Nkind (Subt_Index) = N_Subtype_Indication)
5340 Nkind (Scalar_Range (Etype (Subt_Index))) = N_Range
5343 Target_Typ : constant Entity_Id :=
5344 Etype (Target_Index);
5348 (Scalar_Range (Etype (Subt_Index)),
5351 Defining_Identifier (N));
5353 -- Reset Has_Dynamic_Range_Check on the subtype to
5354 -- prevent elision of the index check due to a dynamic
5355 -- check generated for a preceding index (needed since
5356 -- Insert_Range_Checks tries to avoid generating
5357 -- redundant checks on a given declaration).
5359 Set_Has_Dynamic_Range_Check (N, False);
5365 Sloc (Defining_Identifier (N)));
5367 -- Record whether this index involved a dynamic check
5370 Has_Dyn_Chk or else Has_Dynamic_Range_Check (N);
5374 Next_Index (Subt_Index);
5375 Next_Index (Target_Index);
5378 -- Finally, mark whether the subtype involves dynamic checks
5380 Set_Has_Dynamic_Range_Check (N, Has_Dyn_Chk);
5385 Set_Optimize_Alignment_Flags (Id);
5386 Check_Eliminated (Id);
5389 if Has_Aspects (N) then
5390 Analyze_Aspect_Specifications (N, Id);
5393 Analyze_Dimension (N);
5395 -- Check No_Dynamic_Sized_Objects restriction, which disallows subtype
5396 -- indications on composite types where the constraints are dynamic.
5397 -- Note that object declarations and aggregates generate implicit
5398 -- subtype declarations, which this covers. One special case is that the
5399 -- implicitly generated "=" for discriminated types includes an
5400 -- offending subtype declaration, which is harmless, so we ignore it
5403 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5405 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
5407 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint
5408 and then not (Is_Internal (Id)
5409 and then Is_TSS (Scope (Id),
5410 TSS_Composite_Equality))
5411 and then not Within_Init_Proc
5412 and then not All_Composite_Constraints_Static (Cstr)
5414 Check_Restriction (No_Dynamic_Sized_Objects, Cstr);
5418 end Analyze_Subtype_Declaration;
5420 --------------------------------
5421 -- Analyze_Subtype_Indication --
5422 --------------------------------
5424 procedure Analyze_Subtype_Indication (N : Node_Id) is
5425 T : constant Entity_Id := Subtype_Mark (N);
5426 R : constant Node_Id := Range_Expression (Constraint (N));
5433 Set_Etype (N, Etype (R));
5434 Resolve (R, Entity (T));
5436 Set_Error_Posted (R);
5437 Set_Error_Posted (T);
5439 end Analyze_Subtype_Indication;
5441 --------------------------
5442 -- Analyze_Variant_Part --
5443 --------------------------
5445 procedure Analyze_Variant_Part (N : Node_Id) is
5446 Discr_Name : Node_Id;
5447 Discr_Type : Entity_Id;
5449 procedure Process_Variant (A : Node_Id);
5450 -- Analyze declarations for a single variant
5452 package Analyze_Variant_Choices is
5453 new Generic_Analyze_Choices (Process_Variant);
5454 use Analyze_Variant_Choices;
5456 ---------------------
5457 -- Process_Variant --
5458 ---------------------
5460 procedure Process_Variant (A : Node_Id) is
5461 CL : constant Node_Id := Component_List (A);
5463 if not Null_Present (CL) then
5464 Analyze_Declarations (Component_Items (CL));
5466 if Present (Variant_Part (CL)) then
5467 Analyze (Variant_Part (CL));
5470 end Process_Variant;
5472 -- Start of processing for Analyze_Variant_Part
5475 Discr_Name := Name (N);
5476 Analyze (Discr_Name);
5478 -- If Discr_Name bad, get out (prevent cascaded errors)
5480 if Etype (Discr_Name) = Any_Type then
5484 -- Check invalid discriminant in variant part
5486 if Ekind (Entity (Discr_Name)) /= E_Discriminant then
5487 Error_Msg_N ("invalid discriminant name in variant part", Discr_Name);
5490 Discr_Type := Etype (Entity (Discr_Name));
5492 if not Is_Discrete_Type (Discr_Type) then
5494 ("discriminant in a variant part must be of a discrete type",
5499 -- Now analyze the choices, which also analyzes the declarations that
5500 -- are associated with each choice.
5502 Analyze_Choices (Variants (N), Discr_Type);
5504 -- Note: we used to instantiate and call Check_Choices here to check
5505 -- that the choices covered the discriminant, but it's too early to do
5506 -- that because of statically predicated subtypes, whose analysis may
5507 -- be deferred to their freeze point which may be as late as the freeze
5508 -- point of the containing record. So this call is now to be found in
5509 -- Freeze_Record_Declaration.
5511 end Analyze_Variant_Part;
5513 ----------------------------
5514 -- Array_Type_Declaration --
5515 ----------------------------
5517 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is
5518 Component_Def : constant Node_Id := Component_Definition (Def);
5519 Component_Typ : constant Node_Id := Subtype_Indication (Component_Def);
5520 Element_Type : Entity_Id;
5521 Implicit_Base : Entity_Id;
5523 Related_Id : Entity_Id := Empty;
5525 P : constant Node_Id := Parent (Def);
5529 if Nkind (Def) = N_Constrained_Array_Definition then
5530 Index := First (Discrete_Subtype_Definitions (Def));
5532 Index := First (Subtype_Marks (Def));
5535 -- Find proper names for the implicit types which may be public. In case
5536 -- of anonymous arrays we use the name of the first object of that type
5540 Related_Id := Defining_Identifier (P);
5546 while Present (Index) loop
5549 -- Test for odd case of trying to index a type by the type itself
5551 if Is_Entity_Name (Index) and then Entity (Index) = T then
5552 Error_Msg_N ("type& cannot be indexed by itself", Index);
5553 Set_Entity (Index, Standard_Boolean);
5554 Set_Etype (Index, Standard_Boolean);
5557 -- Check SPARK restriction requiring a subtype mark
5559 if not Nkind_In (Index, N_Identifier, N_Expanded_Name) then
5560 Check_SPARK_05_Restriction ("subtype mark required", Index);
5563 -- Add a subtype declaration for each index of private array type
5564 -- declaration whose etype is also private. For example:
5567 -- type Index is private;
5569 -- type Table is array (Index) of ...
5572 -- This is currently required by the expander for the internally
5573 -- generated equality subprogram of records with variant parts in
5574 -- which the etype of some component is such private type.
5576 if Ekind (Current_Scope) = E_Package
5577 and then In_Private_Part (Current_Scope)
5578 and then Has_Private_Declaration (Etype (Index))
5581 Loc : constant Source_Ptr := Sloc (Def);
5586 New_E := Make_Temporary (Loc, 'T');
5587 Set_Is_Internal (New_E);
5590 Make_Subtype_Declaration (Loc,
5591 Defining_Identifier => New_E,
5592 Subtype_Indication =>
5593 New_Occurrence_Of (Etype (Index), Loc));
5595 Insert_Before (Parent (Def), Decl);
5597 Set_Etype (Index, New_E);
5599 -- If the index is a range the Entity attribute is not
5600 -- available. Example:
5603 -- type T is private;
5605 -- type T is new Natural;
5606 -- Table : array (T(1) .. T(10)) of Boolean;
5609 if Nkind (Index) /= N_Range then
5610 Set_Entity (Index, New_E);
5615 Make_Index (Index, P, Related_Id, Nb_Index);
5617 -- Check error of subtype with predicate for index type
5619 Bad_Predicated_Subtype_Use
5620 ("subtype& has predicate, not allowed as index subtype",
5621 Index, Etype (Index));
5623 -- Move to next index
5626 Nb_Index := Nb_Index + 1;
5629 -- Process subtype indication if one is present
5631 if Present (Component_Typ) then
5632 Element_Type := Process_Subtype (Component_Typ, P, Related_Id, 'C');
5634 Set_Etype (Component_Typ, Element_Type);
5636 if not Nkind_In (Component_Typ, N_Identifier, N_Expanded_Name) then
5637 Check_SPARK_05_Restriction
5638 ("subtype mark required", Component_Typ);
5641 -- Ada 2005 (AI-230): Access Definition case
5643 else pragma Assert (Present (Access_Definition (Component_Def)));
5645 -- Indicate that the anonymous access type is created by the
5646 -- array type declaration.
5648 Element_Type := Access_Definition
5650 N => Access_Definition (Component_Def));
5651 Set_Is_Local_Anonymous_Access (Element_Type);
5653 -- Propagate the parent. This field is needed if we have to generate
5654 -- the master_id associated with an anonymous access to task type
5655 -- component (see Expand_N_Full_Type_Declaration.Build_Master)
5657 Set_Parent (Element_Type, Parent (T));
5659 -- Ada 2005 (AI-230): In case of components that are anonymous access
5660 -- types the level of accessibility depends on the enclosing type
5663 Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230)
5665 -- Ada 2005 (AI-254)
5668 CD : constant Node_Id :=
5669 Access_To_Subprogram_Definition
5670 (Access_Definition (Component_Def));
5672 if Present (CD) and then Protected_Present (CD) then
5674 Replace_Anonymous_Access_To_Protected_Subprogram (Def);
5679 -- Constrained array case
5682 T := Create_Itype (E_Void, P, Related_Id, 'T');
5685 if Nkind (Def) = N_Constrained_Array_Definition then
5687 -- Establish Implicit_Base as unconstrained base type
5689 Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B');
5691 Set_Etype (Implicit_Base, Implicit_Base);
5692 Set_Scope (Implicit_Base, Current_Scope);
5693 Set_Has_Delayed_Freeze (Implicit_Base);
5694 Set_Default_SSO (Implicit_Base);
5696 -- The constrained array type is a subtype of the unconstrained one
5698 Set_Ekind (T, E_Array_Subtype);
5699 Init_Size_Align (T);
5700 Set_Etype (T, Implicit_Base);
5701 Set_Scope (T, Current_Scope);
5702 Set_Is_Constrained (T);
5704 First (Discrete_Subtype_Definitions (Def)));
5705 Set_Has_Delayed_Freeze (T);
5707 -- Complete setup of implicit base type
5709 Set_Component_Size (Implicit_Base, Uint_0);
5710 Set_Component_Type (Implicit_Base, Element_Type);
5711 Set_Finalize_Storage_Only
5713 Finalize_Storage_Only (Element_Type));
5714 Set_First_Index (Implicit_Base, First_Index (T));
5715 Set_Has_Controlled_Component
5717 Has_Controlled_Component (Element_Type)
5718 or else Is_Controlled_Active (Element_Type));
5719 Set_Packed_Array_Impl_Type
5720 (Implicit_Base, Empty);
5722 Propagate_Concurrent_Flags (Implicit_Base, Element_Type);
5724 -- Inherit the "ghostness" from the constrained array type
5726 if Ghost_Mode > None or else Is_Ghost_Entity (T) then
5727 Set_Is_Ghost_Entity (Implicit_Base);
5730 -- Unconstrained array case
5733 Set_Ekind (T, E_Array_Type);
5734 Init_Size_Align (T);
5736 Set_Scope (T, Current_Scope);
5737 Set_Component_Size (T, Uint_0);
5738 Set_Is_Constrained (T, False);
5739 Set_First_Index (T, First (Subtype_Marks (Def)));
5740 Set_Has_Delayed_Freeze (T, True);
5741 Propagate_Concurrent_Flags (T, Element_Type);
5742 Set_Has_Controlled_Component (T, Has_Controlled_Component
5745 Is_Controlled_Active (Element_Type));
5746 Set_Finalize_Storage_Only (T, Finalize_Storage_Only
5748 Set_Default_SSO (T);
5751 -- Common attributes for both cases
5753 Set_Component_Type (Base_Type (T), Element_Type);
5754 Set_Packed_Array_Impl_Type (T, Empty);
5756 if Aliased_Present (Component_Definition (Def)) then
5757 Check_SPARK_05_Restriction
5758 ("aliased is not allowed", Component_Definition (Def));
5759 Set_Has_Aliased_Components (Etype (T));
5762 -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the
5763 -- array type to ensure that objects of this type are initialized.
5765 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (Element_Type) then
5766 Set_Can_Never_Be_Null (T);
5768 if Null_Exclusion_Present (Component_Definition (Def))
5770 -- No need to check itypes because in their case this check was
5771 -- done at their point of creation
5773 and then not Is_Itype (Element_Type)
5776 ("`NOT NULL` not allowed (null already excluded)",
5777 Subtype_Indication (Component_Definition (Def)));
5781 Priv := Private_Component (Element_Type);
5783 if Present (Priv) then
5785 -- Check for circular definitions
5787 if Priv = Any_Type then
5788 Set_Component_Type (Etype (T), Any_Type);
5790 -- There is a gap in the visibility of operations on the composite
5791 -- type only if the component type is defined in a different scope.
5793 elsif Scope (Priv) = Current_Scope then
5796 elsif Is_Limited_Type (Priv) then
5797 Set_Is_Limited_Composite (Etype (T));
5798 Set_Is_Limited_Composite (T);
5800 Set_Is_Private_Composite (Etype (T));
5801 Set_Is_Private_Composite (T);
5805 -- A syntax error in the declaration itself may lead to an empty index
5806 -- list, in which case do a minimal patch.
5808 if No (First_Index (T)) then
5809 Error_Msg_N ("missing index definition in array type declaration", T);
5812 Indexes : constant List_Id :=
5813 New_List (New_Occurrence_Of (Any_Id, Sloc (T)));
5815 Set_Discrete_Subtype_Definitions (Def, Indexes);
5816 Set_First_Index (T, First (Indexes));
5821 -- Create a concatenation operator for the new type. Internal array
5822 -- types created for packed entities do not need such, they are
5823 -- compatible with the user-defined type.
5825 if Number_Dimensions (T) = 1
5826 and then not Is_Packed_Array_Impl_Type (T)
5828 New_Concatenation_Op (T);
5831 -- In the case of an unconstrained array the parser has already verified
5832 -- that all the indexes are unconstrained but we still need to make sure
5833 -- that the element type is constrained.
5835 if not Is_Definite_Subtype (Element_Type) then
5837 ("unconstrained element type in array declaration",
5838 Subtype_Indication (Component_Def));
5840 elsif Is_Abstract_Type (Element_Type) then
5842 ("the type of a component cannot be abstract",
5843 Subtype_Indication (Component_Def));
5846 -- There may be an invariant declared for the component type, but
5847 -- the construction of the component invariant checking procedure
5848 -- takes place during expansion.
5849 end Array_Type_Declaration;
5851 ------------------------------------------------------
5852 -- Replace_Anonymous_Access_To_Protected_Subprogram --
5853 ------------------------------------------------------
5855 function Replace_Anonymous_Access_To_Protected_Subprogram
5856 (N : Node_Id) return Entity_Id
5858 Loc : constant Source_Ptr := Sloc (N);
5860 Curr_Scope : constant Scope_Stack_Entry :=
5861 Scope_Stack.Table (Scope_Stack.Last);
5863 Anon : constant Entity_Id := Make_Temporary (Loc, 'S');
5866 -- Access definition in declaration
5869 -- Object definition or formal definition with an access definition
5872 -- Declaration of anonymous access to subprogram type
5875 -- Original specification in access to subprogram
5880 Set_Is_Internal (Anon);
5883 when N_Component_Declaration |
5884 N_Unconstrained_Array_Definition |
5885 N_Constrained_Array_Definition =>
5886 Comp := Component_Definition (N);
5887 Acc := Access_Definition (Comp);
5889 when N_Discriminant_Specification =>
5890 Comp := Discriminant_Type (N);
5893 when N_Parameter_Specification =>
5894 Comp := Parameter_Type (N);
5897 when N_Access_Function_Definition =>
5898 Comp := Result_Definition (N);
5901 when N_Object_Declaration =>
5902 Comp := Object_Definition (N);
5905 when N_Function_Specification =>
5906 Comp := Result_Definition (N);
5910 raise Program_Error;
5913 Spec := Access_To_Subprogram_Definition (Acc);
5916 Make_Full_Type_Declaration (Loc,
5917 Defining_Identifier => Anon,
5918 Type_Definition => Copy_Separate_Tree (Spec));
5920 Mark_Rewrite_Insertion (Decl);
5922 -- In ASIS mode, analyze the profile on the original node, because
5923 -- the separate copy does not provide enough links to recover the
5924 -- original tree. Analysis is limited to type annotations, within
5925 -- a temporary scope that serves as an anonymous subprogram to collect
5926 -- otherwise useless temporaries and itypes.
5930 Typ : constant Entity_Id := Make_Temporary (Loc, 'S');
5933 if Nkind (Spec) = N_Access_Function_Definition then
5934 Set_Ekind (Typ, E_Function);
5936 Set_Ekind (Typ, E_Procedure);
5939 Set_Parent (Typ, N);
5940 Set_Scope (Typ, Current_Scope);
5943 -- Nothing to do if procedure is parameterless
5945 if Present (Parameter_Specifications (Spec)) then
5946 Process_Formals (Parameter_Specifications (Spec), Spec);
5949 if Nkind (Spec) = N_Access_Function_Definition then
5951 Def : constant Node_Id := Result_Definition (Spec);
5954 -- The result might itself be an anonymous access type, so
5957 if Nkind (Def) = N_Access_Definition then
5958 if Present (Access_To_Subprogram_Definition (Def)) then
5961 Replace_Anonymous_Access_To_Protected_Subprogram
5964 Find_Type (Subtype_Mark (Def));
5977 -- Insert the new declaration in the nearest enclosing scope. If the
5978 -- parent is a body and N is its return type, the declaration belongs
5979 -- in the enclosing scope. Likewise if N is the type of a parameter.
5983 if Nkind (N) = N_Function_Specification
5984 and then Nkind (P) = N_Subprogram_Body
5987 elsif Nkind (N) = N_Parameter_Specification
5988 and then Nkind (P) in N_Subprogram_Specification
5989 and then Nkind (Parent (P)) = N_Subprogram_Body
5991 P := Parent (Parent (P));
5994 while Present (P) and then not Has_Declarations (P) loop
5998 pragma Assert (Present (P));
6000 if Nkind (P) = N_Package_Specification then
6001 Prepend (Decl, Visible_Declarations (P));
6003 Prepend (Decl, Declarations (P));
6006 -- Replace the anonymous type with an occurrence of the new declaration.
6007 -- In all cases the rewritten node does not have the null-exclusion
6008 -- attribute because (if present) it was already inherited by the
6009 -- anonymous entity (Anon). Thus, in case of components we do not
6010 -- inherit this attribute.
6012 if Nkind (N) = N_Parameter_Specification then
6013 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
6014 Set_Etype (Defining_Identifier (N), Anon);
6015 Set_Null_Exclusion_Present (N, False);
6017 elsif Nkind (N) = N_Object_Declaration then
6018 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
6019 Set_Etype (Defining_Identifier (N), Anon);
6021 elsif Nkind (N) = N_Access_Function_Definition then
6022 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
6024 elsif Nkind (N) = N_Function_Specification then
6025 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
6026 Set_Etype (Defining_Unit_Name (N), Anon);
6030 Make_Component_Definition (Loc,
6031 Subtype_Indication => New_Occurrence_Of (Anon, Loc)));
6034 Mark_Rewrite_Insertion (Comp);
6036 if Nkind_In (N, N_Object_Declaration, N_Access_Function_Definition)
6037 or else (Nkind (Parent (N)) = N_Full_Type_Declaration
6038 and then not Is_Type (Current_Scope))
6041 -- Declaration can be analyzed in the current scope.
6046 -- Temporarily remove the current scope (record or subprogram) from
6047 -- the stack to add the new declarations to the enclosing scope.
6048 -- The anonymous entity is an Itype with the proper attributes.
6050 Scope_Stack.Decrement_Last;
6052 Set_Is_Itype (Anon);
6053 Set_Associated_Node_For_Itype (Anon, N);
6054 Scope_Stack.Append (Curr_Scope);
6057 Set_Ekind (Anon, E_Anonymous_Access_Protected_Subprogram_Type);
6058 Set_Can_Use_Internal_Rep (Anon, not Always_Compatible_Rep_On_Target);
6060 end Replace_Anonymous_Access_To_Protected_Subprogram;
6062 -------------------------------
6063 -- Build_Derived_Access_Type --
6064 -------------------------------
6066 procedure Build_Derived_Access_Type
6068 Parent_Type : Entity_Id;
6069 Derived_Type : Entity_Id)
6071 S : constant Node_Id := Subtype_Indication (Type_Definition (N));
6073 Desig_Type : Entity_Id;
6075 Discr_Con_Elist : Elist_Id;
6076 Discr_Con_El : Elmt_Id;
6080 -- Set the designated type so it is available in case this is an access
6081 -- to a self-referential type, e.g. a standard list type with a next
6082 -- pointer. Will be reset after subtype is built.
6084 Set_Directly_Designated_Type
6085 (Derived_Type, Designated_Type (Parent_Type));
6087 Subt := Process_Subtype (S, N);
6089 if Nkind (S) /= N_Subtype_Indication
6090 and then Subt /= Base_Type (Subt)
6092 Set_Ekind (Derived_Type, E_Access_Subtype);
6095 if Ekind (Derived_Type) = E_Access_Subtype then
6097 Pbase : constant Entity_Id := Base_Type (Parent_Type);
6098 Ibase : constant Entity_Id :=
6099 Create_Itype (Ekind (Pbase), N, Derived_Type, 'B');
6100 Svg_Chars : constant Name_Id := Chars (Ibase);
6101 Svg_Next_E : constant Entity_Id := Next_Entity (Ibase);
6104 Copy_Node (Pbase, Ibase);
6106 -- Restore Itype status after Copy_Node
6108 Set_Is_Itype (Ibase);
6109 Set_Associated_Node_For_Itype (Ibase, N);
6111 Set_Chars (Ibase, Svg_Chars);
6112 Set_Next_Entity (Ibase, Svg_Next_E);
6113 Set_Sloc (Ibase, Sloc (Derived_Type));
6114 Set_Scope (Ibase, Scope (Derived_Type));
6115 Set_Freeze_Node (Ibase, Empty);
6116 Set_Is_Frozen (Ibase, False);
6117 Set_Comes_From_Source (Ibase, False);
6118 Set_Is_First_Subtype (Ibase, False);
6120 Set_Etype (Ibase, Pbase);
6121 Set_Etype (Derived_Type, Ibase);
6125 Set_Directly_Designated_Type
6126 (Derived_Type, Designated_Type (Subt));
6128 Set_Is_Constrained (Derived_Type, Is_Constrained (Subt));
6129 Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type));
6130 Set_Size_Info (Derived_Type, Parent_Type);
6131 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
6132 Set_Depends_On_Private (Derived_Type,
6133 Has_Private_Component (Derived_Type));
6134 Conditional_Delay (Derived_Type, Subt);
6136 -- Ada 2005 (AI-231): Set the null-exclusion attribute, and verify
6137 -- that it is not redundant.
6139 if Null_Exclusion_Present (Type_Definition (N)) then
6140 Set_Can_Never_Be_Null (Derived_Type);
6142 elsif Can_Never_Be_Null (Parent_Type) then
6143 Set_Can_Never_Be_Null (Derived_Type);
6146 -- Note: we do not copy the Storage_Size_Variable, since we always go to
6147 -- the root type for this information.
6149 -- Apply range checks to discriminants for derived record case
6150 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
6152 Desig_Type := Designated_Type (Derived_Type);
6154 if Is_Composite_Type (Desig_Type)
6155 and then (not Is_Array_Type (Desig_Type))
6156 and then Has_Discriminants (Desig_Type)
6157 and then Base_Type (Desig_Type) /= Desig_Type
6159 Discr_Con_Elist := Discriminant_Constraint (Desig_Type);
6160 Discr_Con_El := First_Elmt (Discr_Con_Elist);
6162 Discr := First_Discriminant (Base_Type (Desig_Type));
6163 while Present (Discr_Con_El) loop
6164 Apply_Range_Check (Node (Discr_Con_El), Etype (Discr));
6165 Next_Elmt (Discr_Con_El);
6166 Next_Discriminant (Discr);
6169 end Build_Derived_Access_Type;
6171 ------------------------------
6172 -- Build_Derived_Array_Type --
6173 ------------------------------
6175 procedure Build_Derived_Array_Type
6177 Parent_Type : Entity_Id;
6178 Derived_Type : Entity_Id)
6180 Loc : constant Source_Ptr := Sloc (N);
6181 Tdef : constant Node_Id := Type_Definition (N);
6182 Indic : constant Node_Id := Subtype_Indication (Tdef);
6183 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
6184 Implicit_Base : Entity_Id;
6185 New_Indic : Node_Id;
6187 procedure Make_Implicit_Base;
6188 -- If the parent subtype is constrained, the derived type is a subtype
6189 -- of an implicit base type derived from the parent base.
6191 ------------------------
6192 -- Make_Implicit_Base --
6193 ------------------------
6195 procedure Make_Implicit_Base is
6198 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
6200 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
6201 Set_Etype (Implicit_Base, Parent_Base);
6203 Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base);
6204 Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base);
6206 Set_Has_Delayed_Freeze (Implicit_Base, True);
6208 -- Inherit the "ghostness" from the parent base type
6210 if Ghost_Mode > None or else Is_Ghost_Entity (Parent_Base) then
6211 Set_Is_Ghost_Entity (Implicit_Base);
6213 end Make_Implicit_Base;
6215 -- Start of processing for Build_Derived_Array_Type
6218 if not Is_Constrained (Parent_Type) then
6219 if Nkind (Indic) /= N_Subtype_Indication then
6220 Set_Ekind (Derived_Type, E_Array_Type);
6222 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
6223 Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type);
6225 Set_Has_Delayed_Freeze (Derived_Type, True);
6229 Set_Etype (Derived_Type, Implicit_Base);
6232 Make_Subtype_Declaration (Loc,
6233 Defining_Identifier => Derived_Type,
6234 Subtype_Indication =>
6235 Make_Subtype_Indication (Loc,
6236 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6237 Constraint => Constraint (Indic)));
6239 Rewrite (N, New_Indic);
6244 if Nkind (Indic) /= N_Subtype_Indication then
6247 Set_Ekind (Derived_Type, Ekind (Parent_Type));
6248 Set_Etype (Derived_Type, Implicit_Base);
6249 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
6252 Error_Msg_N ("illegal constraint on constrained type", Indic);
6256 -- If parent type is not a derived type itself, and is declared in
6257 -- closed scope (e.g. a subprogram), then we must explicitly introduce
6258 -- the new type's concatenation operator since Derive_Subprograms
6259 -- will not inherit the parent's operator. If the parent type is
6260 -- unconstrained, the operator is of the unconstrained base type.
6262 if Number_Dimensions (Parent_Type) = 1
6263 and then not Is_Limited_Type (Parent_Type)
6264 and then not Is_Derived_Type (Parent_Type)
6265 and then not Is_Package_Or_Generic_Package
6266 (Scope (Base_Type (Parent_Type)))
6268 if not Is_Constrained (Parent_Type)
6269 and then Is_Constrained (Derived_Type)
6271 New_Concatenation_Op (Implicit_Base);
6273 New_Concatenation_Op (Derived_Type);
6276 end Build_Derived_Array_Type;
6278 -----------------------------------
6279 -- Build_Derived_Concurrent_Type --
6280 -----------------------------------
6282 procedure Build_Derived_Concurrent_Type
6284 Parent_Type : Entity_Id;
6285 Derived_Type : Entity_Id)
6287 Loc : constant Source_Ptr := Sloc (N);
6289 Corr_Record : constant Entity_Id := Make_Temporary (Loc, 'C');
6290 Corr_Decl : Node_Id;
6291 Corr_Decl_Needed : Boolean;
6292 -- If the derived type has fewer discriminants than its parent, the
6293 -- corresponding record is also a derived type, in order to account for
6294 -- the bound discriminants. We create a full type declaration for it in
6297 Constraint_Present : constant Boolean :=
6298 Nkind (Subtype_Indication (Type_Definition (N))) =
6299 N_Subtype_Indication;
6301 D_Constraint : Node_Id;
6302 New_Constraint : Elist_Id;
6303 Old_Disc : Entity_Id;
6304 New_Disc : Entity_Id;
6308 Set_Stored_Constraint (Derived_Type, No_Elist);
6309 Corr_Decl_Needed := False;
6312 if Present (Discriminant_Specifications (N))
6313 and then Constraint_Present
6315 Old_Disc := First_Discriminant (Parent_Type);
6316 New_Disc := First (Discriminant_Specifications (N));
6317 while Present (New_Disc) and then Present (Old_Disc) loop
6318 Next_Discriminant (Old_Disc);
6323 if Present (Old_Disc) and then Expander_Active then
6325 -- The new type has fewer discriminants, so we need to create a new
6326 -- corresponding record, which is derived from the corresponding
6327 -- record of the parent, and has a stored constraint that captures
6328 -- the values of the discriminant constraints. The corresponding
6329 -- record is needed only if expander is active and code generation is
6332 -- The type declaration for the derived corresponding record has the
6333 -- same discriminant part and constraints as the current declaration.
6334 -- Copy the unanalyzed tree to build declaration.
6336 Corr_Decl_Needed := True;
6337 New_N := Copy_Separate_Tree (N);
6340 Make_Full_Type_Declaration (Loc,
6341 Defining_Identifier => Corr_Record,
6342 Discriminant_Specifications =>
6343 Discriminant_Specifications (New_N),
6345 Make_Derived_Type_Definition (Loc,
6346 Subtype_Indication =>
6347 Make_Subtype_Indication (Loc,
6350 (Corresponding_Record_Type (Parent_Type), Loc),
6353 (Subtype_Indication (Type_Definition (New_N))))));
6356 -- Copy Storage_Size and Relative_Deadline variables if task case
6358 if Is_Task_Type (Parent_Type) then
6359 Set_Storage_Size_Variable (Derived_Type,
6360 Storage_Size_Variable (Parent_Type));
6361 Set_Relative_Deadline_Variable (Derived_Type,
6362 Relative_Deadline_Variable (Parent_Type));
6365 if Present (Discriminant_Specifications (N)) then
6366 Push_Scope (Derived_Type);
6367 Check_Or_Process_Discriminants (N, Derived_Type);
6369 if Constraint_Present then
6371 Expand_To_Stored_Constraint
6373 Build_Discriminant_Constraints
6375 Subtype_Indication (Type_Definition (N)), True));
6380 elsif Constraint_Present then
6382 -- Build constrained subtype, copying the constraint, and derive
6383 -- from it to create a derived constrained type.
6386 Loc : constant Source_Ptr := Sloc (N);
6387 Anon : constant Entity_Id :=
6388 Make_Defining_Identifier (Loc,
6389 Chars => New_External_Name (Chars (Derived_Type), 'T'));
6394 Make_Subtype_Declaration (Loc,
6395 Defining_Identifier => Anon,
6396 Subtype_Indication =>
6397 New_Copy_Tree (Subtype_Indication (Type_Definition (N))));
6398 Insert_Before (N, Decl);
6401 Rewrite (Subtype_Indication (Type_Definition (N)),
6402 New_Occurrence_Of (Anon, Loc));
6403 Set_Analyzed (Derived_Type, False);
6409 -- By default, operations and private data are inherited from parent.
6410 -- However, in the presence of bound discriminants, a new corresponding
6411 -- record will be created, see below.
6413 Set_Has_Discriminants
6414 (Derived_Type, Has_Discriminants (Parent_Type));
6415 Set_Corresponding_Record_Type
6416 (Derived_Type, Corresponding_Record_Type (Parent_Type));
6418 -- Is_Constrained is set according the parent subtype, but is set to
6419 -- False if the derived type is declared with new discriminants.
6423 (Is_Constrained (Parent_Type) or else Constraint_Present)
6424 and then not Present (Discriminant_Specifications (N)));
6426 if Constraint_Present then
6427 if not Has_Discriminants (Parent_Type) then
6428 Error_Msg_N ("untagged parent must have discriminants", N);
6430 elsif Present (Discriminant_Specifications (N)) then
6432 -- Verify that new discriminants are used to constrain old ones
6437 (Constraint (Subtype_Indication (Type_Definition (N)))));
6439 Old_Disc := First_Discriminant (Parent_Type);
6441 while Present (D_Constraint) loop
6442 if Nkind (D_Constraint) /= N_Discriminant_Association then
6444 -- Positional constraint. If it is a reference to a new
6445 -- discriminant, it constrains the corresponding old one.
6447 if Nkind (D_Constraint) = N_Identifier then
6448 New_Disc := First_Discriminant (Derived_Type);
6449 while Present (New_Disc) loop
6450 exit when Chars (New_Disc) = Chars (D_Constraint);
6451 Next_Discriminant (New_Disc);
6454 if Present (New_Disc) then
6455 Set_Corresponding_Discriminant (New_Disc, Old_Disc);
6459 Next_Discriminant (Old_Disc);
6461 -- if this is a named constraint, search by name for the old
6462 -- discriminants constrained by the new one.
6464 elsif Nkind (Expression (D_Constraint)) = N_Identifier then
6466 -- Find new discriminant with that name
6468 New_Disc := First_Discriminant (Derived_Type);
6469 while Present (New_Disc) loop
6471 Chars (New_Disc) = Chars (Expression (D_Constraint));
6472 Next_Discriminant (New_Disc);
6475 if Present (New_Disc) then
6477 -- Verify that new discriminant renames some discriminant
6478 -- of the parent type, and associate the new discriminant
6479 -- with one or more old ones that it renames.
6485 Selector := First (Selector_Names (D_Constraint));
6486 while Present (Selector) loop
6487 Old_Disc := First_Discriminant (Parent_Type);
6488 while Present (Old_Disc) loop
6489 exit when Chars (Old_Disc) = Chars (Selector);
6490 Next_Discriminant (Old_Disc);
6493 if Present (Old_Disc) then
6494 Set_Corresponding_Discriminant
6495 (New_Disc, Old_Disc);
6504 Next (D_Constraint);
6507 New_Disc := First_Discriminant (Derived_Type);
6508 while Present (New_Disc) loop
6509 if No (Corresponding_Discriminant (New_Disc)) then
6511 ("new discriminant& must constrain old one", N, New_Disc);
6514 Subtypes_Statically_Compatible
6516 Etype (Corresponding_Discriminant (New_Disc)))
6519 ("& not statically compatible with parent discriminant",
6523 Next_Discriminant (New_Disc);
6527 elsif Present (Discriminant_Specifications (N)) then
6529 ("missing discriminant constraint in untagged derivation", N);
6532 -- The entity chain of the derived type includes the new discriminants
6533 -- but shares operations with the parent.
6535 if Present (Discriminant_Specifications (N)) then
6536 Old_Disc := First_Discriminant (Parent_Type);
6537 while Present (Old_Disc) loop
6538 if No (Next_Entity (Old_Disc))
6539 or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant
6542 (Last_Entity (Derived_Type), Next_Entity (Old_Disc));
6546 Next_Discriminant (Old_Disc);
6550 Set_First_Entity (Derived_Type, First_Entity (Parent_Type));
6551 if Has_Discriminants (Parent_Type) then
6552 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6553 Set_Discriminant_Constraint (
6554 Derived_Type, Discriminant_Constraint (Parent_Type));
6558 Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type));
6560 Set_Has_Completion (Derived_Type);
6562 if Corr_Decl_Needed then
6563 Set_Stored_Constraint (Derived_Type, New_Constraint);
6564 Insert_After (N, Corr_Decl);
6565 Analyze (Corr_Decl);
6566 Set_Corresponding_Record_Type (Derived_Type, Corr_Record);
6568 end Build_Derived_Concurrent_Type;
6570 ------------------------------------
6571 -- Build_Derived_Enumeration_Type --
6572 ------------------------------------
6574 procedure Build_Derived_Enumeration_Type
6576 Parent_Type : Entity_Id;
6577 Derived_Type : Entity_Id)
6579 Loc : constant Source_Ptr := Sloc (N);
6580 Def : constant Node_Id := Type_Definition (N);
6581 Indic : constant Node_Id := Subtype_Indication (Def);
6582 Implicit_Base : Entity_Id;
6583 Literal : Entity_Id;
6584 New_Lit : Entity_Id;
6585 Literals_List : List_Id;
6586 Type_Decl : Node_Id;
6588 Rang_Expr : Node_Id;
6591 -- Since types Standard.Character and Standard.[Wide_]Wide_Character do
6592 -- not have explicit literals lists we need to process types derived
6593 -- from them specially. This is handled by Derived_Standard_Character.
6594 -- If the parent type is a generic type, there are no literals either,
6595 -- and we construct the same skeletal representation as for the generic
6598 if Is_Standard_Character_Type (Parent_Type) then
6599 Derived_Standard_Character (N, Parent_Type, Derived_Type);
6601 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
6607 if Nkind (Indic) /= N_Subtype_Indication then
6609 Make_Attribute_Reference (Loc,
6610 Attribute_Name => Name_First,
6611 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6612 Set_Etype (Lo, Derived_Type);
6615 Make_Attribute_Reference (Loc,
6616 Attribute_Name => Name_Last,
6617 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6618 Set_Etype (Hi, Derived_Type);
6620 Set_Scalar_Range (Derived_Type,
6626 -- Analyze subtype indication and verify compatibility
6627 -- with parent type.
6629 if Base_Type (Process_Subtype (Indic, N)) /=
6630 Base_Type (Parent_Type)
6633 ("illegal constraint for formal discrete type", N);
6639 -- If a constraint is present, analyze the bounds to catch
6640 -- premature usage of the derived literals.
6642 if Nkind (Indic) = N_Subtype_Indication
6643 and then Nkind (Range_Expression (Constraint (Indic))) = N_Range
6645 Analyze (Low_Bound (Range_Expression (Constraint (Indic))));
6646 Analyze (High_Bound (Range_Expression (Constraint (Indic))));
6649 -- Introduce an implicit base type for the derived type even if there
6650 -- is no constraint attached to it, since this seems closer to the
6651 -- Ada semantics. Build a full type declaration tree for the derived
6652 -- type using the implicit base type as the defining identifier. The
6653 -- build a subtype declaration tree which applies the constraint (if
6654 -- any) have it replace the derived type declaration.
6656 Literal := First_Literal (Parent_Type);
6657 Literals_List := New_List;
6658 while Present (Literal)
6659 and then Ekind (Literal) = E_Enumeration_Literal
6661 -- Literals of the derived type have the same representation as
6662 -- those of the parent type, but this representation can be
6663 -- overridden by an explicit representation clause. Indicate
6664 -- that there is no explicit representation given yet. These
6665 -- derived literals are implicit operations of the new type,
6666 -- and can be overridden by explicit ones.
6668 if Nkind (Literal) = N_Defining_Character_Literal then
6670 Make_Defining_Character_Literal (Loc, Chars (Literal));
6672 New_Lit := Make_Defining_Identifier (Loc, Chars (Literal));
6675 Set_Ekind (New_Lit, E_Enumeration_Literal);
6676 Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal));
6677 Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal));
6678 Set_Enumeration_Rep_Expr (New_Lit, Empty);
6679 Set_Alias (New_Lit, Literal);
6680 Set_Is_Known_Valid (New_Lit, True);
6682 Append (New_Lit, Literals_List);
6683 Next_Literal (Literal);
6687 Make_Defining_Identifier (Sloc (Derived_Type),
6688 Chars => New_External_Name (Chars (Derived_Type), 'B'));
6690 -- Indicate the proper nature of the derived type. This must be done
6691 -- before analysis of the literals, to recognize cases when a literal
6692 -- may be hidden by a previous explicit function definition (cf.
6695 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
6696 Set_Etype (Derived_Type, Implicit_Base);
6699 Make_Full_Type_Declaration (Loc,
6700 Defining_Identifier => Implicit_Base,
6701 Discriminant_Specifications => No_List,
6703 Make_Enumeration_Type_Definition (Loc, Literals_List));
6705 Mark_Rewrite_Insertion (Type_Decl);
6706 Insert_Before (N, Type_Decl);
6707 Analyze (Type_Decl);
6709 -- The anonymous base now has a full declaration, but this base
6710 -- is not a first subtype.
6712 Set_Is_First_Subtype (Implicit_Base, False);
6714 -- After the implicit base is analyzed its Etype needs to be changed
6715 -- to reflect the fact that it is derived from the parent type which
6716 -- was ignored during analysis. We also set the size at this point.
6718 Set_Etype (Implicit_Base, Parent_Type);
6720 Set_Size_Info (Implicit_Base, Parent_Type);
6721 Set_RM_Size (Implicit_Base, RM_Size (Parent_Type));
6722 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type));
6724 -- Copy other flags from parent type
6726 Set_Has_Non_Standard_Rep
6727 (Implicit_Base, Has_Non_Standard_Rep
6729 Set_Has_Pragma_Ordered
6730 (Implicit_Base, Has_Pragma_Ordered
6732 Set_Has_Delayed_Freeze (Implicit_Base);
6734 -- Process the subtype indication including a validation check on the
6735 -- constraint, if any. If a constraint is given, its bounds must be
6736 -- implicitly converted to the new type.
6738 if Nkind (Indic) = N_Subtype_Indication then
6740 R : constant Node_Id :=
6741 Range_Expression (Constraint (Indic));
6744 if Nkind (R) = N_Range then
6745 Hi := Build_Scalar_Bound
6746 (High_Bound (R), Parent_Type, Implicit_Base);
6747 Lo := Build_Scalar_Bound
6748 (Low_Bound (R), Parent_Type, Implicit_Base);
6751 -- Constraint is a Range attribute. Replace with explicit
6752 -- mention of the bounds of the prefix, which must be a
6755 Analyze (Prefix (R));
6757 Convert_To (Implicit_Base,
6758 Make_Attribute_Reference (Loc,
6759 Attribute_Name => Name_Last,
6761 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6764 Convert_To (Implicit_Base,
6765 Make_Attribute_Reference (Loc,
6766 Attribute_Name => Name_First,
6768 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6775 (Type_High_Bound (Parent_Type),
6776 Parent_Type, Implicit_Base);
6779 (Type_Low_Bound (Parent_Type),
6780 Parent_Type, Implicit_Base);
6788 -- If we constructed a default range for the case where no range
6789 -- was given, then the expressions in the range must not freeze
6790 -- since they do not correspond to expressions in the source.
6792 if Nkind (Indic) /= N_Subtype_Indication then
6793 Set_Must_Not_Freeze (Lo);
6794 Set_Must_Not_Freeze (Hi);
6795 Set_Must_Not_Freeze (Rang_Expr);
6799 Make_Subtype_Declaration (Loc,
6800 Defining_Identifier => Derived_Type,
6801 Subtype_Indication =>
6802 Make_Subtype_Indication (Loc,
6803 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6805 Make_Range_Constraint (Loc,
6806 Range_Expression => Rang_Expr))));
6810 -- Propagate the aspects from the original type declaration to the
6811 -- declaration of the implicit base.
6813 Move_Aspects (From => Original_Node (N), To => Type_Decl);
6815 -- Apply a range check. Since this range expression doesn't have an
6816 -- Etype, we have to specifically pass the Source_Typ parameter. Is
6819 if Nkind (Indic) = N_Subtype_Indication then
6821 (Range_Expression (Constraint (Indic)), Parent_Type,
6822 Source_Typ => Entity (Subtype_Mark (Indic)));
6825 end Build_Derived_Enumeration_Type;
6827 --------------------------------
6828 -- Build_Derived_Numeric_Type --
6829 --------------------------------
6831 procedure Build_Derived_Numeric_Type
6833 Parent_Type : Entity_Id;
6834 Derived_Type : Entity_Id)
6836 Loc : constant Source_Ptr := Sloc (N);
6837 Tdef : constant Node_Id := Type_Definition (N);
6838 Indic : constant Node_Id := Subtype_Indication (Tdef);
6839 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
6840 No_Constraint : constant Boolean := Nkind (Indic) /=
6841 N_Subtype_Indication;
6842 Implicit_Base : Entity_Id;
6848 -- Process the subtype indication including a validation check on
6849 -- the constraint if any.
6851 Discard_Node (Process_Subtype (Indic, N));
6853 -- Introduce an implicit base type for the derived type even if there
6854 -- is no constraint attached to it, since this seems closer to the Ada
6858 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
6860 Set_Etype (Implicit_Base, Parent_Base);
6861 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
6862 Set_Size_Info (Implicit_Base, Parent_Base);
6863 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base));
6864 Set_Parent (Implicit_Base, Parent (Derived_Type));
6865 Set_Is_Known_Valid (Implicit_Base, Is_Known_Valid (Parent_Base));
6867 -- Set RM Size for discrete type or decimal fixed-point type
6868 -- Ordinary fixed-point is excluded, why???
6870 if Is_Discrete_Type (Parent_Base)
6871 or else Is_Decimal_Fixed_Point_Type (Parent_Base)
6873 Set_RM_Size (Implicit_Base, RM_Size (Parent_Base));
6876 Set_Has_Delayed_Freeze (Implicit_Base);
6878 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
6879 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
6881 Set_Scalar_Range (Implicit_Base,
6886 if Has_Infinities (Parent_Base) then
6887 Set_Includes_Infinities (Scalar_Range (Implicit_Base));
6890 -- The Derived_Type, which is the entity of the declaration, is a
6891 -- subtype of the implicit base. Its Ekind is a subtype, even in the
6892 -- absence of an explicit constraint.
6894 Set_Etype (Derived_Type, Implicit_Base);
6896 -- If we did not have a constraint, then the Ekind is set from the
6897 -- parent type (otherwise Process_Subtype has set the bounds)
6899 if No_Constraint then
6900 Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type)));
6903 -- If we did not have a range constraint, then set the range from the
6904 -- parent type. Otherwise, the Process_Subtype call has set the bounds.
6906 if No_Constraint or else not Has_Range_Constraint (Indic) then
6907 Set_Scalar_Range (Derived_Type,
6909 Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)),
6910 High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type))));
6911 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6913 if Has_Infinities (Parent_Type) then
6914 Set_Includes_Infinities (Scalar_Range (Derived_Type));
6917 Set_Is_Known_Valid (Derived_Type, Is_Known_Valid (Parent_Type));
6920 Set_Is_Descendant_Of_Address (Derived_Type,
6921 Is_Descendant_Of_Address (Parent_Type));
6922 Set_Is_Descendant_Of_Address (Implicit_Base,
6923 Is_Descendant_Of_Address (Parent_Type));
6925 -- Set remaining type-specific fields, depending on numeric type
6927 if Is_Modular_Integer_Type (Parent_Type) then
6928 Set_Modulus (Implicit_Base, Modulus (Parent_Base));
6930 Set_Non_Binary_Modulus
6931 (Implicit_Base, Non_Binary_Modulus (Parent_Base));
6934 (Implicit_Base, Is_Known_Valid (Parent_Base));
6936 elsif Is_Floating_Point_Type (Parent_Type) then
6938 -- Digits of base type is always copied from the digits value of
6939 -- the parent base type, but the digits of the derived type will
6940 -- already have been set if there was a constraint present.
6942 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6943 Set_Float_Rep (Implicit_Base, Float_Rep (Parent_Base));
6945 if No_Constraint then
6946 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type));
6949 elsif Is_Fixed_Point_Type (Parent_Type) then
6951 -- Small of base type and derived type are always copied from the
6952 -- parent base type, since smalls never change. The delta of the
6953 -- base type is also copied from the parent base type. However the
6954 -- delta of the derived type will have been set already if a
6955 -- constraint was present.
6957 Set_Small_Value (Derived_Type, Small_Value (Parent_Base));
6958 Set_Small_Value (Implicit_Base, Small_Value (Parent_Base));
6959 Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base));
6961 if No_Constraint then
6962 Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type));
6965 -- The scale and machine radix in the decimal case are always
6966 -- copied from the parent base type.
6968 if Is_Decimal_Fixed_Point_Type (Parent_Type) then
6969 Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base));
6970 Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base));
6972 Set_Machine_Radix_10
6973 (Derived_Type, Machine_Radix_10 (Parent_Base));
6974 Set_Machine_Radix_10
6975 (Implicit_Base, Machine_Radix_10 (Parent_Base));
6977 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6979 if No_Constraint then
6980 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base));
6983 -- the analysis of the subtype_indication sets the
6984 -- digits value of the derived type.
6991 if Is_Integer_Type (Parent_Type) then
6992 Set_Has_Shift_Operator
6993 (Implicit_Base, Has_Shift_Operator (Parent_Type));
6996 -- The type of the bounds is that of the parent type, and they
6997 -- must be converted to the derived type.
6999 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
7001 -- The implicit_base should be frozen when the derived type is frozen,
7002 -- but note that it is used in the conversions of the bounds. For fixed
7003 -- types we delay the determination of the bounds until the proper
7004 -- freezing point. For other numeric types this is rejected by GCC, for
7005 -- reasons that are currently unclear (???), so we choose to freeze the
7006 -- implicit base now. In the case of integers and floating point types
7007 -- this is harmless because subsequent representation clauses cannot
7008 -- affect anything, but it is still baffling that we cannot use the
7009 -- same mechanism for all derived numeric types.
7011 -- There is a further complication: actually some representation
7012 -- clauses can affect the implicit base type. For example, attribute
7013 -- definition clauses for stream-oriented attributes need to set the
7014 -- corresponding TSS entries on the base type, and this normally
7015 -- cannot be done after the base type is frozen, so the circuitry in
7016 -- Sem_Ch13.New_Stream_Subprogram must account for this possibility
7017 -- and not use Set_TSS in this case.
7019 -- There are also consequences for the case of delayed representation
7020 -- aspects for some cases. For example, a Size aspect is delayed and
7021 -- should not be evaluated to the freeze point. This early freezing
7022 -- means that the size attribute evaluation happens too early???
7024 if Is_Fixed_Point_Type (Parent_Type) then
7025 Conditional_Delay (Implicit_Base, Parent_Type);
7027 Freeze_Before (N, Implicit_Base);
7029 end Build_Derived_Numeric_Type;
7031 --------------------------------
7032 -- Build_Derived_Private_Type --
7033 --------------------------------
7035 procedure Build_Derived_Private_Type
7037 Parent_Type : Entity_Id;
7038 Derived_Type : Entity_Id;
7039 Is_Completion : Boolean;
7040 Derive_Subps : Boolean := True)
7042 Loc : constant Source_Ptr := Sloc (N);
7043 Par_Base : constant Entity_Id := Base_Type (Parent_Type);
7044 Par_Scope : constant Entity_Id := Scope (Par_Base);
7045 Full_N : constant Node_Id := New_Copy_Tree (N);
7046 Full_Der : Entity_Id := New_Copy (Derived_Type);
7049 procedure Build_Full_Derivation;
7050 -- Build full derivation, i.e. derive from the full view
7052 procedure Copy_And_Build;
7053 -- Copy derived type declaration, replace parent with its full view,
7054 -- and build derivation
7056 ---------------------------
7057 -- Build_Full_Derivation --
7058 ---------------------------
7060 procedure Build_Full_Derivation is
7062 -- If parent scope is not open, install the declarations
7064 if not In_Open_Scopes (Par_Scope) then
7065 Install_Private_Declarations (Par_Scope);
7066 Install_Visible_Declarations (Par_Scope);
7068 Uninstall_Declarations (Par_Scope);
7070 -- If parent scope is open and in another unit, and parent has a
7071 -- completion, then the derivation is taking place in the visible
7072 -- part of a child unit. In that case retrieve the full view of
7073 -- the parent momentarily.
7075 elsif not In_Same_Source_Unit (N, Parent_Type) then
7076 Full_P := Full_View (Parent_Type);
7077 Exchange_Declarations (Parent_Type);
7079 Exchange_Declarations (Full_P);
7081 -- Otherwise it is a local derivation
7086 end Build_Full_Derivation;
7088 --------------------
7089 -- Copy_And_Build --
7090 --------------------
7092 procedure Copy_And_Build is
7093 Full_Parent : Entity_Id := Parent_Type;
7096 -- If the parent is itself derived from another private type,
7097 -- installing the private declarations has not affected its
7098 -- privacy status, so use its own full view explicitly.
7100 if Is_Private_Type (Full_Parent)
7101 and then Present (Full_View (Full_Parent))
7103 Full_Parent := Full_View (Full_Parent);
7106 -- And its underlying full view if necessary
7108 if Is_Private_Type (Full_Parent)
7109 and then Present (Underlying_Full_View (Full_Parent))
7111 Full_Parent := Underlying_Full_View (Full_Parent);
7114 -- For record, access and most enumeration types, derivation from
7115 -- the full view requires a fully-fledged declaration. In the other
7116 -- cases, just use an itype.
7118 if Ekind (Full_Parent) in Record_Kind
7119 or else Ekind (Full_Parent) in Access_Kind
7121 (Ekind (Full_Parent) in Enumeration_Kind
7122 and then not Is_Standard_Character_Type (Full_Parent)
7123 and then not Is_Generic_Type (Root_Type (Full_Parent)))
7125 -- Copy and adjust declaration to provide a completion for what
7126 -- is originally a private declaration. Indicate that full view
7127 -- is internally generated.
7129 Set_Comes_From_Source (Full_N, False);
7130 Set_Comes_From_Source (Full_Der, False);
7131 Set_Parent (Full_Der, Full_N);
7132 Set_Defining_Identifier (Full_N, Full_Der);
7134 -- If there are no constraints, adjust the subtype mark
7136 if Nkind (Subtype_Indication (Type_Definition (Full_N))) /=
7137 N_Subtype_Indication
7139 Set_Subtype_Indication
7140 (Type_Definition (Full_N),
7141 New_Occurrence_Of (Full_Parent, Sloc (Full_N)));
7144 Insert_After (N, Full_N);
7146 -- Build full view of derived type from full view of parent which
7147 -- is now installed. Subprograms have been derived on the partial
7148 -- view, the completion does not derive them anew.
7150 if Ekind (Full_Parent) in Record_Kind then
7152 -- If parent type is tagged, the completion inherits the proper
7153 -- primitive operations.
7155 if Is_Tagged_Type (Parent_Type) then
7156 Build_Derived_Record_Type
7157 (Full_N, Full_Parent, Full_Der, Derive_Subps);
7159 Build_Derived_Record_Type
7160 (Full_N, Full_Parent, Full_Der, Derive_Subps => False);
7165 (Full_N, Full_Parent, Full_Der,
7166 Is_Completion => False, Derive_Subps => False);
7169 -- The full declaration has been introduced into the tree and
7170 -- processed in the step above. It should not be analyzed again
7171 -- (when encountered later in the current list of declarations)
7172 -- to prevent spurious name conflicts. The full entity remains
7175 Set_Analyzed (Full_N);
7179 Make_Defining_Identifier (Sloc (Derived_Type),
7180 Chars => Chars (Derived_Type));
7181 Set_Is_Itype (Full_Der);
7182 Set_Associated_Node_For_Itype (Full_Der, N);
7183 Set_Parent (Full_Der, N);
7185 (N, Full_Parent, Full_Der,
7186 Is_Completion => False, Derive_Subps => False);
7189 Set_Has_Private_Declaration (Full_Der);
7190 Set_Has_Private_Declaration (Derived_Type);
7192 Set_Scope (Full_Der, Scope (Derived_Type));
7193 Set_Is_First_Subtype (Full_Der, Is_First_Subtype (Derived_Type));
7194 Set_Has_Size_Clause (Full_Der, False);
7195 Set_Has_Alignment_Clause (Full_Der, False);
7196 Set_Has_Delayed_Freeze (Full_Der);
7197 Set_Is_Frozen (Full_Der, False);
7198 Set_Freeze_Node (Full_Der, Empty);
7199 Set_Depends_On_Private (Full_Der, Has_Private_Component (Full_Der));
7200 Set_Is_Public (Full_Der, Is_Public (Derived_Type));
7202 -- The convention on the base type may be set in the private part
7203 -- and not propagated to the subtype until later, so we obtain the
7204 -- convention from the base type of the parent.
7206 Set_Convention (Full_Der, Convention (Base_Type (Full_Parent)));
7209 -- Start of processing for Build_Derived_Private_Type
7212 if Is_Tagged_Type (Parent_Type) then
7213 Full_P := Full_View (Parent_Type);
7215 -- A type extension of a type with unknown discriminants is an
7216 -- indefinite type that the back-end cannot handle directly.
7217 -- We treat it as a private type, and build a completion that is
7218 -- derived from the full view of the parent, and hopefully has
7219 -- known discriminants.
7221 -- If the full view of the parent type has an underlying record view,
7222 -- use it to generate the underlying record view of this derived type
7223 -- (required for chains of derivations with unknown discriminants).
7225 -- Minor optimization: we avoid the generation of useless underlying
7226 -- record view entities if the private type declaration has unknown
7227 -- discriminants but its corresponding full view has no
7230 if Has_Unknown_Discriminants (Parent_Type)
7231 and then Present (Full_P)
7232 and then (Has_Discriminants (Full_P)
7233 or else Present (Underlying_Record_View (Full_P)))
7234 and then not In_Open_Scopes (Par_Scope)
7235 and then Expander_Active
7238 Full_Der : constant Entity_Id := Make_Temporary (Loc, 'T');
7239 New_Ext : constant Node_Id :=
7241 (Record_Extension_Part (Type_Definition (N)));
7245 Build_Derived_Record_Type
7246 (N, Parent_Type, Derived_Type, Derive_Subps);
7248 -- Build anonymous completion, as a derivation from the full
7249 -- view of the parent. This is not a completion in the usual
7250 -- sense, because the current type is not private.
7253 Make_Full_Type_Declaration (Loc,
7254 Defining_Identifier => Full_Der,
7256 Make_Derived_Type_Definition (Loc,
7257 Subtype_Indication =>
7259 (Subtype_Indication (Type_Definition (N))),
7260 Record_Extension_Part => New_Ext));
7262 -- If the parent type has an underlying record view, use it
7263 -- here to build the new underlying record view.
7265 if Present (Underlying_Record_View (Full_P)) then
7267 (Nkind (Subtype_Indication (Type_Definition (Decl)))
7269 Set_Entity (Subtype_Indication (Type_Definition (Decl)),
7270 Underlying_Record_View (Full_P));
7273 Install_Private_Declarations (Par_Scope);
7274 Install_Visible_Declarations (Par_Scope);
7275 Insert_Before (N, Decl);
7277 -- Mark entity as an underlying record view before analysis,
7278 -- to avoid generating the list of its primitive operations
7279 -- (which is not really required for this entity) and thus
7280 -- prevent spurious errors associated with missing overriding
7281 -- of abstract primitives (overridden only for Derived_Type).
7283 Set_Ekind (Full_Der, E_Record_Type);
7284 Set_Is_Underlying_Record_View (Full_Der);
7285 Set_Default_SSO (Full_Der);
7289 pragma Assert (Has_Discriminants (Full_Der)
7290 and then not Has_Unknown_Discriminants (Full_Der));
7292 Uninstall_Declarations (Par_Scope);
7294 -- Freeze the underlying record view, to prevent generation of
7295 -- useless dispatching information, which is simply shared with
7296 -- the real derived type.
7298 Set_Is_Frozen (Full_Der);
7300 -- If the derived type has access discriminants, create
7301 -- references to their anonymous types now, to prevent
7302 -- back-end problems when their first use is in generated
7303 -- bodies of primitives.
7309 E := First_Entity (Full_Der);
7311 while Present (E) loop
7312 if Ekind (E) = E_Discriminant
7313 and then Ekind (Etype (E)) = E_Anonymous_Access_Type
7315 Build_Itype_Reference (Etype (E), Decl);
7322 -- Set up links between real entity and underlying record view
7324 Set_Underlying_Record_View (Derived_Type, Base_Type (Full_Der));
7325 Set_Underlying_Record_View (Base_Type (Full_Der), Derived_Type);
7328 -- If discriminants are known, build derived record
7331 Build_Derived_Record_Type
7332 (N, Parent_Type, Derived_Type, Derive_Subps);
7337 elsif Has_Discriminants (Parent_Type) then
7339 -- Build partial view of derived type from partial view of parent.
7340 -- This must be done before building the full derivation because the
7341 -- second derivation will modify the discriminants of the first and
7342 -- the discriminants are chained with the rest of the components in
7343 -- the full derivation.
7345 Build_Derived_Record_Type
7346 (N, Parent_Type, Derived_Type, Derive_Subps);
7348 -- Build the full derivation if this is not the anonymous derived
7349 -- base type created by Build_Derived_Record_Type in the constrained
7350 -- case (see point 5. of its head comment) since we build it for the
7351 -- derived subtype. And skip it for protected types altogether, as
7352 -- gigi does not use these types directly.
7354 if Present (Full_View (Parent_Type))
7355 and then not Is_Itype (Derived_Type)
7356 and then not (Ekind (Full_View (Parent_Type)) in Protected_Kind)
7359 Der_Base : constant Entity_Id := Base_Type (Derived_Type);
7361 Last_Discr : Entity_Id;
7364 -- If this is not a completion, construct the implicit full
7365 -- view by deriving from the full view of the parent type.
7366 -- But if this is a completion, the derived private type
7367 -- being built is a full view and the full derivation can
7368 -- only be its underlying full view.
7370 Build_Full_Derivation;
7372 if not Is_Completion then
7373 Set_Full_View (Derived_Type, Full_Der);
7375 Set_Underlying_Full_View (Derived_Type, Full_Der);
7378 if not Is_Base_Type (Derived_Type) then
7379 Set_Full_View (Der_Base, Base_Type (Full_Der));
7382 -- Copy the discriminant list from full view to the partial
7383 -- view (base type and its subtype). Gigi requires that the
7384 -- partial and full views have the same discriminants.
7386 -- Note that since the partial view points to discriminants
7387 -- in the full view, their scope will be that of the full
7388 -- view. This might cause some front end problems and need
7391 Discr := First_Discriminant (Base_Type (Full_Der));
7392 Set_First_Entity (Der_Base, Discr);
7395 Last_Discr := Discr;
7396 Next_Discriminant (Discr);
7397 exit when No (Discr);
7400 Set_Last_Entity (Der_Base, Last_Discr);
7401 Set_First_Entity (Derived_Type, First_Entity (Der_Base));
7402 Set_Last_Entity (Derived_Type, Last_Entity (Der_Base));
7404 Set_Stored_Constraint
7405 (Full_Der, Stored_Constraint (Derived_Type));
7409 elsif Present (Full_View (Parent_Type))
7410 and then Has_Discriminants (Full_View (Parent_Type))
7412 if Has_Unknown_Discriminants (Parent_Type)
7413 and then Nkind (Subtype_Indication (Type_Definition (N))) =
7414 N_Subtype_Indication
7417 ("cannot constrain type with unknown discriminants",
7418 Subtype_Indication (Type_Definition (N)));
7422 -- If this is not a completion, construct the implicit full view by
7423 -- deriving from the full view of the parent type. But if this is a
7424 -- completion, the derived private type being built is a full view
7425 -- and the full derivation can only be its underlying full view.
7427 Build_Full_Derivation;
7429 if not Is_Completion then
7430 Set_Full_View (Derived_Type, Full_Der);
7432 Set_Underlying_Full_View (Derived_Type, Full_Der);
7435 -- In any case, the primitive operations are inherited from the
7436 -- parent type, not from the internal full view.
7438 Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type));
7440 if Derive_Subps then
7441 Derive_Subprograms (Parent_Type, Derived_Type);
7444 Set_Stored_Constraint (Derived_Type, No_Elist);
7446 (Derived_Type, Is_Constrained (Full_View (Parent_Type)));
7449 -- Untagged type, No discriminants on either view
7451 if Nkind (Subtype_Indication (Type_Definition (N))) =
7452 N_Subtype_Indication
7455 ("illegal constraint on type without discriminants", N);
7458 if Present (Discriminant_Specifications (N))
7459 and then Present (Full_View (Parent_Type))
7460 and then not Is_Tagged_Type (Full_View (Parent_Type))
7462 Error_Msg_N ("cannot add discriminants to untagged type", N);
7465 Set_Stored_Constraint (Derived_Type, No_Elist);
7466 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
7467 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
7468 Set_Disable_Controlled (Derived_Type, Disable_Controlled
7470 Set_Has_Controlled_Component
7471 (Derived_Type, Has_Controlled_Component
7474 -- Direct controlled types do not inherit Finalize_Storage_Only flag
7476 if not Is_Controlled_Active (Parent_Type) then
7477 Set_Finalize_Storage_Only
7478 (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type));
7481 -- If this is not a completion, construct the implicit full view by
7482 -- deriving from the full view of the parent type.
7484 -- ??? If the parent is untagged private and its completion is
7485 -- tagged, this mechanism will not work because we cannot derive from
7486 -- the tagged full view unless we have an extension.
7488 if Present (Full_View (Parent_Type))
7489 and then not Is_Tagged_Type (Full_View (Parent_Type))
7490 and then not Is_Completion
7492 Build_Full_Derivation;
7493 Set_Full_View (Derived_Type, Full_Der);
7497 Set_Has_Unknown_Discriminants (Derived_Type,
7498 Has_Unknown_Discriminants (Parent_Type));
7500 if Is_Private_Type (Derived_Type) then
7501 Set_Private_Dependents (Derived_Type, New_Elmt_List);
7504 -- If the parent base type is in scope, add the derived type to its
7505 -- list of private dependents, because its full view may become
7506 -- visible subsequently (in a nested private part, a body, or in a
7507 -- further child unit).
7509 if Is_Private_Type (Par_Base) and then In_Open_Scopes (Par_Scope) then
7510 Append_Elmt (Derived_Type, Private_Dependents (Parent_Type));
7512 -- Check for unusual case where a type completed by a private
7513 -- derivation occurs within a package nested in a child unit, and
7514 -- the parent is declared in an ancestor.
7516 if Is_Child_Unit (Scope (Current_Scope))
7517 and then Is_Completion
7518 and then In_Private_Part (Current_Scope)
7519 and then Scope (Parent_Type) /= Current_Scope
7521 -- Note that if the parent has a completion in the private part,
7522 -- (which is itself a derivation from some other private type)
7523 -- it is that completion that is visible, there is no full view
7524 -- available, and no special processing is needed.
7526 and then Present (Full_View (Parent_Type))
7528 -- In this case, the full view of the parent type will become
7529 -- visible in the body of the enclosing child, and only then will
7530 -- the current type be possibly non-private. Build an underlying
7531 -- full view that will be installed when the enclosing child body
7534 if Present (Underlying_Full_View (Derived_Type)) then
7535 Full_Der := Underlying_Full_View (Derived_Type);
7537 Build_Full_Derivation;
7538 Set_Underlying_Full_View (Derived_Type, Full_Der);
7541 -- The full view will be used to swap entities on entry/exit to
7542 -- the body, and must appear in the entity list for the package.
7544 Append_Entity (Full_Der, Scope (Derived_Type));
7547 end Build_Derived_Private_Type;
7549 -------------------------------
7550 -- Build_Derived_Record_Type --
7551 -------------------------------
7555 -- Ideally we would like to use the same model of type derivation for
7556 -- tagged and untagged record types. Unfortunately this is not quite
7557 -- possible because the semantics of representation clauses is different
7558 -- for tagged and untagged records under inheritance. Consider the
7561 -- type R (...) is [tagged] record ... end record;
7562 -- type T (...) is new R (...) [with ...];
7564 -- The representation clauses for T can specify a completely different
7565 -- record layout from R's. Hence the same component can be placed in two
7566 -- very different positions in objects of type T and R. If R and T are
7567 -- tagged types, representation clauses for T can only specify the layout
7568 -- of non inherited components, thus components that are common in R and T
7569 -- have the same position in objects of type R and T.
7571 -- This has two implications. The first is that the entire tree for R's
7572 -- declaration needs to be copied for T in the untagged case, so that T
7573 -- can be viewed as a record type of its own with its own representation
7574 -- clauses. The second implication is the way we handle discriminants.
7575 -- Specifically, in the untagged case we need a way to communicate to Gigi
7576 -- what are the real discriminants in the record, while for the semantics
7577 -- we need to consider those introduced by the user to rename the
7578 -- discriminants in the parent type. This is handled by introducing the
7579 -- notion of stored discriminants. See below for more.
7581 -- Fortunately the way regular components are inherited can be handled in
7582 -- the same way in tagged and untagged types.
7584 -- To complicate things a bit more the private view of a private extension
7585 -- cannot be handled in the same way as the full view (for one thing the
7586 -- semantic rules are somewhat different). We will explain what differs
7589 -- 2. DISCRIMINANTS UNDER INHERITANCE
7591 -- The semantic rules governing the discriminants of derived types are
7594 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
7595 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
7597 -- If parent type has discriminants, then the discriminants that are
7598 -- declared in the derived type are [3.4 (11)]:
7600 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
7603 -- o Otherwise, each discriminant of the parent type (implicitly declared
7604 -- in the same order with the same specifications). In this case, the
7605 -- discriminants are said to be "inherited", or if unknown in the parent
7606 -- are also unknown in the derived type.
7608 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
7610 -- o The parent subtype must be constrained;
7612 -- o If the parent type is not a tagged type, then each discriminant of
7613 -- the derived type must be used in the constraint defining a parent
7614 -- subtype. [Implementation note: This ensures that the new discriminant
7615 -- can share storage with an existing discriminant.]
7617 -- For the derived type each discriminant of the parent type is either
7618 -- inherited, constrained to equal some new discriminant of the derived
7619 -- type, or constrained to the value of an expression.
7621 -- When inherited or constrained to equal some new discriminant, the
7622 -- parent discriminant and the discriminant of the derived type are said
7625 -- If a discriminant of the parent type is constrained to a specific value
7626 -- in the derived type definition, then the discriminant is said to be
7627 -- "specified" by that derived type definition.
7629 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES
7631 -- We have spoken about stored discriminants in point 1 (introduction)
7632 -- above. There are two sort of stored discriminants: implicit and
7633 -- explicit. As long as the derived type inherits the same discriminants as
7634 -- the root record type, stored discriminants are the same as regular
7635 -- discriminants, and are said to be implicit. However, if any discriminant
7636 -- in the root type was renamed in the derived type, then the derived
7637 -- type will contain explicit stored discriminants. Explicit stored
7638 -- discriminants are discriminants in addition to the semantically visible
7639 -- discriminants defined for the derived type. Stored discriminants are
7640 -- used by Gigi to figure out what are the physical discriminants in
7641 -- objects of the derived type (see precise definition in einfo.ads).
7642 -- As an example, consider the following:
7644 -- type R (D1, D2, D3 : Int) is record ... end record;
7645 -- type T1 is new R;
7646 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
7647 -- type T3 is new T2;
7648 -- type T4 (Y : Int) is new T3 (Y, 99);
7650 -- The following table summarizes the discriminants and stored
7651 -- discriminants in R and T1 through T4.
7653 -- Type Discrim Stored Discrim Comment
7654 -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R
7655 -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1
7656 -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2
7657 -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3
7658 -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4
7660 -- Field Corresponding_Discriminant (abbreviated CD below) allows us to
7661 -- find the corresponding discriminant in the parent type, while
7662 -- Original_Record_Component (abbreviated ORC below), the actual physical
7663 -- component that is renamed. Finally the field Is_Completely_Hidden
7664 -- (abbreviated ICH below) is set for all explicit stored discriminants
7665 -- (see einfo.ads for more info). For the above example this gives:
7667 -- Discrim CD ORC ICH
7668 -- ^^^^^^^ ^^ ^^^ ^^^
7669 -- D1 in R empty itself no
7670 -- D2 in R empty itself no
7671 -- D3 in R empty itself no
7673 -- D1 in T1 D1 in R itself no
7674 -- D2 in T1 D2 in R itself no
7675 -- D3 in T1 D3 in R itself no
7677 -- X1 in T2 D3 in T1 D3 in T2 no
7678 -- X2 in T2 D1 in T1 D1 in T2 no
7679 -- D1 in T2 empty itself yes
7680 -- D2 in T2 empty itself yes
7681 -- D3 in T2 empty itself yes
7683 -- X1 in T3 X1 in T2 D3 in T3 no
7684 -- X2 in T3 X2 in T2 D1 in T3 no
7685 -- D1 in T3 empty itself yes
7686 -- D2 in T3 empty itself yes
7687 -- D3 in T3 empty itself yes
7689 -- Y in T4 X1 in T3 D3 in T3 no
7690 -- D1 in T3 empty itself yes
7691 -- D2 in T3 empty itself yes
7692 -- D3 in T3 empty itself yes
7694 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES
7696 -- Type derivation for tagged types is fairly straightforward. If no
7697 -- discriminants are specified by the derived type, these are inherited
7698 -- from the parent. No explicit stored discriminants are ever necessary.
7699 -- The only manipulation that is done to the tree is that of adding a
7700 -- _parent field with parent type and constrained to the same constraint
7701 -- specified for the parent in the derived type definition. For instance:
7703 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
7704 -- type T1 is new R with null record;
7705 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
7707 -- are changed into:
7709 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
7710 -- _parent : R (D1, D2, D3);
7713 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
7714 -- _parent : T1 (X2, 88, X1);
7717 -- The discriminants actually present in R, T1 and T2 as well as their CD,
7718 -- ORC and ICH fields are:
7720 -- Discrim CD ORC ICH
7721 -- ^^^^^^^ ^^ ^^^ ^^^
7722 -- D1 in R empty itself no
7723 -- D2 in R empty itself no
7724 -- D3 in R empty itself no
7726 -- D1 in T1 D1 in R D1 in R no
7727 -- D2 in T1 D2 in R D2 in R no
7728 -- D3 in T1 D3 in R D3 in R no
7730 -- X1 in T2 D3 in T1 D3 in R no
7731 -- X2 in T2 D1 in T1 D1 in R no
7733 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS
7735 -- Regardless of whether we dealing with a tagged or untagged type
7736 -- we will transform all derived type declarations of the form
7738 -- type T is new R (...) [with ...];
7740 -- subtype S is R (...);
7741 -- type T is new S [with ...];
7743 -- type BT is new R [with ...];
7744 -- subtype T is BT (...);
7746 -- That is, the base derived type is constrained only if it has no
7747 -- discriminants. The reason for doing this is that GNAT's semantic model
7748 -- assumes that a base type with discriminants is unconstrained.
7750 -- Note that, strictly speaking, the above transformation is not always
7751 -- correct. Consider for instance the following excerpt from ACVC b34011a:
7753 -- procedure B34011A is
7754 -- type REC (D : integer := 0) is record
7759 -- type T6 is new Rec;
7760 -- function F return T6;
7765 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
7768 -- The definition of Q6.U is illegal. However transforming Q6.U into
7770 -- type BaseU is new T6;
7771 -- subtype U is BaseU (Q6.F.I)
7773 -- turns U into a legal subtype, which is incorrect. To avoid this problem
7774 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
7775 -- the transformation described above.
7777 -- There is another instance where the above transformation is incorrect.
7781 -- type Base (D : Integer) is tagged null record;
7782 -- procedure P (X : Base);
7784 -- type Der is new Base (2) with null record;
7785 -- procedure P (X : Der);
7788 -- Then the above transformation turns this into
7790 -- type Der_Base is new Base with null record;
7791 -- -- procedure P (X : Base) is implicitly inherited here
7792 -- -- as procedure P (X : Der_Base).
7794 -- subtype Der is Der_Base (2);
7795 -- procedure P (X : Der);
7796 -- -- The overriding of P (X : Der_Base) is illegal since we
7797 -- -- have a parameter conformance problem.
7799 -- To get around this problem, after having semantically processed Der_Base
7800 -- and the rewritten subtype declaration for Der, we copy Der_Base field
7801 -- Discriminant_Constraint from Der so that when parameter conformance is
7802 -- checked when P is overridden, no semantic errors are flagged.
7804 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS
7806 -- Regardless of whether we are dealing with a tagged or untagged type
7807 -- we will transform all derived type declarations of the form
7809 -- type R (D1, .., Dn : ...) is [tagged] record ...;
7810 -- type T is new R [with ...];
7812 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
7814 -- The reason for such transformation is that it allows us to implement a
7815 -- very clean form of component inheritance as explained below.
7817 -- Note that this transformation is not achieved by direct tree rewriting
7818 -- and manipulation, but rather by redoing the semantic actions that the
7819 -- above transformation will entail. This is done directly in routine
7820 -- Inherit_Components.
7822 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE
7824 -- In both tagged and untagged derived types, regular non discriminant
7825 -- components are inherited in the derived type from the parent type. In
7826 -- the absence of discriminants component, inheritance is straightforward
7827 -- as components can simply be copied from the parent.
7829 -- If the parent has discriminants, inheriting components constrained with
7830 -- these discriminants requires caution. Consider the following example:
7832 -- type R (D1, D2 : Positive) is [tagged] record
7833 -- S : String (D1 .. D2);
7836 -- type T1 is new R [with null record];
7837 -- type T2 (X : positive) is new R (1, X) [with null record];
7839 -- As explained in 6. above, T1 is rewritten as
7840 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
7841 -- which makes the treatment for T1 and T2 identical.
7843 -- What we want when inheriting S, is that references to D1 and D2 in R are
7844 -- replaced with references to their correct constraints, i.e. D1 and D2 in
7845 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
7846 -- with either discriminant references in the derived type or expressions.
7847 -- This replacement is achieved as follows: before inheriting R's
7848 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
7849 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
7850 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
7851 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
7852 -- by String (1 .. X).
7854 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS
7856 -- We explain here the rules governing private type extensions relevant to
7857 -- type derivation. These rules are explained on the following example:
7859 -- type D [(...)] is new A [(...)] with private; <-- partial view
7860 -- type D [(...)] is new P [(...)] with null record; <-- full view
7862 -- Type A is called the ancestor subtype of the private extension.
7863 -- Type P is the parent type of the full view of the private extension. It
7864 -- must be A or a type derived from A.
7866 -- The rules concerning the discriminants of private type extensions are
7869 -- o If a private extension inherits known discriminants from the ancestor
7870 -- subtype, then the full view must also inherit its discriminants from
7871 -- the ancestor subtype and the parent subtype of the full view must be
7872 -- constrained if and only if the ancestor subtype is constrained.
7874 -- o If a partial view has unknown discriminants, then the full view may
7875 -- define a definite or an indefinite subtype, with or without
7878 -- o If a partial view has neither known nor unknown discriminants, then
7879 -- the full view must define a definite subtype.
7881 -- o If the ancestor subtype of a private extension has constrained
7882 -- discriminants, then the parent subtype of the full view must impose a
7883 -- statically matching constraint on those discriminants.
7885 -- This means that only the following forms of private extensions are
7888 -- type D is new A with private; <-- partial view
7889 -- type D is new P with null record; <-- full view
7891 -- If A has no discriminants than P has no discriminants, otherwise P must
7892 -- inherit A's discriminants.
7894 -- type D is new A (...) with private; <-- partial view
7895 -- type D is new P (:::) with null record; <-- full view
7897 -- P must inherit A's discriminants and (...) and (:::) must statically
7900 -- subtype A is R (...);
7901 -- type D is new A with private; <-- partial view
7902 -- type D is new P with null record; <-- full view
7904 -- P must have inherited R's discriminants and must be derived from A or
7905 -- any of its subtypes.
7907 -- type D (..) is new A with private; <-- partial view
7908 -- type D (..) is new P [(:::)] with null record; <-- full view
7910 -- No specific constraints on P's discriminants or constraint (:::).
7911 -- Note that A can be unconstrained, but the parent subtype P must either
7912 -- be constrained or (:::) must be present.
7914 -- type D (..) is new A [(...)] with private; <-- partial view
7915 -- type D (..) is new P [(:::)] with null record; <-- full view
7917 -- P's constraints on A's discriminants must statically match those
7918 -- imposed by (...).
7920 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS
7922 -- The full view of a private extension is handled exactly as described
7923 -- above. The model chose for the private view of a private extension is
7924 -- the same for what concerns discriminants (i.e. they receive the same
7925 -- treatment as in the tagged case). However, the private view of the
7926 -- private extension always inherits the components of the parent base,
7927 -- without replacing any discriminant reference. Strictly speaking this is
7928 -- incorrect. However, Gigi never uses this view to generate code so this
7929 -- is a purely semantic issue. In theory, a set of transformations similar
7930 -- to those given in 5. and 6. above could be applied to private views of
7931 -- private extensions to have the same model of component inheritance as
7932 -- for non private extensions. However, this is not done because it would
7933 -- further complicate private type processing. Semantically speaking, this
7934 -- leaves us in an uncomfortable situation. As an example consider:
7937 -- type R (D : integer) is tagged record
7938 -- S : String (1 .. D);
7940 -- procedure P (X : R);
7941 -- type T is new R (1) with private;
7943 -- type T is new R (1) with null record;
7946 -- This is transformed into:
7949 -- type R (D : integer) is tagged record
7950 -- S : String (1 .. D);
7952 -- procedure P (X : R);
7953 -- type T is new R (1) with private;
7955 -- type BaseT is new R with null record;
7956 -- subtype T is BaseT (1);
7959 -- (strictly speaking the above is incorrect Ada)
7961 -- From the semantic standpoint the private view of private extension T
7962 -- should be flagged as constrained since one can clearly have
7966 -- in a unit withing Pack. However, when deriving subprograms for the
7967 -- private view of private extension T, T must be seen as unconstrained
7968 -- since T has discriminants (this is a constraint of the current
7969 -- subprogram derivation model). Thus, when processing the private view of
7970 -- a private extension such as T, we first mark T as unconstrained, we
7971 -- process it, we perform program derivation and just before returning from
7972 -- Build_Derived_Record_Type we mark T as constrained.
7974 -- ??? Are there are other uncomfortable cases that we will have to
7977 -- 10. RECORD_TYPE_WITH_PRIVATE complications
7979 -- Types that are derived from a visible record type and have a private
7980 -- extension present other peculiarities. They behave mostly like private
7981 -- types, but if they have primitive operations defined, these will not
7982 -- have the proper signatures for further inheritance, because other
7983 -- primitive operations will use the implicit base that we define for
7984 -- private derivations below. This affect subprogram inheritance (see
7985 -- Derive_Subprograms for details). We also derive the implicit base from
7986 -- the base type of the full view, so that the implicit base is a record
7987 -- type and not another private type, This avoids infinite loops.
7989 procedure Build_Derived_Record_Type
7991 Parent_Type : Entity_Id;
7992 Derived_Type : Entity_Id;
7993 Derive_Subps : Boolean := True)
7995 Discriminant_Specs : constant Boolean :=
7996 Present (Discriminant_Specifications (N));
7997 Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type);
7998 Loc : constant Source_Ptr := Sloc (N);
7999 Private_Extension : constant Boolean :=
8000 Nkind (N) = N_Private_Extension_Declaration;
8001 Assoc_List : Elist_Id;
8002 Constraint_Present : Boolean;
8004 Discrim : Entity_Id;
8006 Inherit_Discrims : Boolean := False;
8007 Last_Discrim : Entity_Id;
8008 New_Base : Entity_Id;
8010 New_Discrs : Elist_Id;
8011 New_Indic : Node_Id;
8012 Parent_Base : Entity_Id;
8013 Save_Etype : Entity_Id;
8014 Save_Discr_Constr : Elist_Id;
8015 Save_Next_Entity : Entity_Id;
8018 Discs : Elist_Id := New_Elmt_List;
8019 -- An empty Discs list means that there were no constraints in the
8020 -- subtype indication or that there was an error processing it.
8023 if Ekind (Parent_Type) = E_Record_Type_With_Private
8024 and then Present (Full_View (Parent_Type))
8025 and then Has_Discriminants (Parent_Type)
8027 Parent_Base := Base_Type (Full_View (Parent_Type));
8029 Parent_Base := Base_Type (Parent_Type);
8032 -- AI05-0115 : if this is a derivation from a private type in some
8033 -- other scope that may lead to invisible components for the derived
8034 -- type, mark it accordingly.
8036 if Is_Private_Type (Parent_Type) then
8037 if Scope (Parent_Type) = Scope (Derived_Type) then
8040 elsif In_Open_Scopes (Scope (Parent_Type))
8041 and then In_Private_Part (Scope (Parent_Type))
8046 Set_Has_Private_Ancestor (Derived_Type);
8050 Set_Has_Private_Ancestor
8051 (Derived_Type, Has_Private_Ancestor (Parent_Type));
8054 -- Before we start the previously documented transformations, here is
8055 -- little fix for size and alignment of tagged types. Normally when we
8056 -- derive type D from type P, we copy the size and alignment of P as the
8057 -- default for D, and in the absence of explicit representation clauses
8058 -- for D, the size and alignment are indeed the same as the parent.
8060 -- But this is wrong for tagged types, since fields may be added, and
8061 -- the default size may need to be larger, and the default alignment may
8062 -- need to be larger.
8064 -- We therefore reset the size and alignment fields in the tagged case.
8065 -- Note that the size and alignment will in any case be at least as
8066 -- large as the parent type (since the derived type has a copy of the
8067 -- parent type in the _parent field)
8069 -- The type is also marked as being tagged here, which is needed when
8070 -- processing components with a self-referential anonymous access type
8071 -- in the call to Check_Anonymous_Access_Components below. Note that
8072 -- this flag is also set later on for completeness.
8075 Set_Is_Tagged_Type (Derived_Type);
8076 Init_Size_Align (Derived_Type);
8079 -- STEP 0a: figure out what kind of derived type declaration we have
8081 if Private_Extension then
8083 Set_Ekind (Derived_Type, E_Record_Type_With_Private);
8084 Set_Default_SSO (Derived_Type);
8087 Type_Def := Type_Definition (N);
8089 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
8090 -- Parent_Base can be a private type or private extension. However,
8091 -- for tagged types with an extension the newly added fields are
8092 -- visible and hence the Derived_Type is always an E_Record_Type.
8093 -- (except that the parent may have its own private fields).
8094 -- For untagged types we preserve the Ekind of the Parent_Base.
8096 if Present (Record_Extension_Part (Type_Def)) then
8097 Set_Ekind (Derived_Type, E_Record_Type);
8098 Set_Default_SSO (Derived_Type);
8100 -- Create internal access types for components with anonymous
8103 if Ada_Version >= Ada_2005 then
8104 Check_Anonymous_Access_Components
8105 (N, Derived_Type, Derived_Type,
8106 Component_List (Record_Extension_Part (Type_Def)));
8110 Set_Ekind (Derived_Type, Ekind (Parent_Base));
8114 -- Indic can either be an N_Identifier if the subtype indication
8115 -- contains no constraint or an N_Subtype_Indication if the subtype
8116 -- indication has a constraint.
8118 Indic := Subtype_Indication (Type_Def);
8119 Constraint_Present := (Nkind (Indic) = N_Subtype_Indication);
8121 -- Check that the type has visible discriminants. The type may be
8122 -- a private type with unknown discriminants whose full view has
8123 -- discriminants which are invisible.
8125 if Constraint_Present then
8126 if not Has_Discriminants (Parent_Base)
8128 (Has_Unknown_Discriminants (Parent_Base)
8129 and then Is_Private_Type (Parent_Base))
8132 ("invalid constraint: type has no discriminant",
8133 Constraint (Indic));
8135 Constraint_Present := False;
8136 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
8138 elsif Is_Constrained (Parent_Type) then
8140 ("invalid constraint: parent type is already constrained",
8141 Constraint (Indic));
8143 Constraint_Present := False;
8144 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
8148 -- STEP 0b: If needed, apply transformation given in point 5. above
8150 if not Private_Extension
8151 and then Has_Discriminants (Parent_Type)
8152 and then not Discriminant_Specs
8153 and then (Is_Constrained (Parent_Type) or else Constraint_Present)
8155 -- First, we must analyze the constraint (see comment in point 5.)
8156 -- The constraint may come from the subtype indication of the full
8159 if Constraint_Present then
8160 New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic);
8162 -- If there is no explicit constraint, there might be one that is
8163 -- inherited from a constrained parent type. In that case verify that
8164 -- it conforms to the constraint in the partial view. In perverse
8165 -- cases the parent subtypes of the partial and full view can have
8166 -- different constraints.
8168 elsif Present (Stored_Constraint (Parent_Type)) then
8169 New_Discrs := Stored_Constraint (Parent_Type);
8172 New_Discrs := No_Elist;
8175 if Has_Discriminants (Derived_Type)
8176 and then Has_Private_Declaration (Derived_Type)
8177 and then Present (Discriminant_Constraint (Derived_Type))
8178 and then Present (New_Discrs)
8180 -- Verify that constraints of the full view statically match
8181 -- those given in the partial view.
8187 C1 := First_Elmt (New_Discrs);
8188 C2 := First_Elmt (Discriminant_Constraint (Derived_Type));
8189 while Present (C1) and then Present (C2) loop
8190 if Fully_Conformant_Expressions (Node (C1), Node (C2))
8192 (Is_OK_Static_Expression (Node (C1))
8193 and then Is_OK_Static_Expression (Node (C2))
8195 Expr_Value (Node (C1)) = Expr_Value (Node (C2)))
8200 if Constraint_Present then
8202 ("constraint not conformant to previous declaration",
8206 ("constraint of full view is incompatible "
8207 & "with partial view", N);
8217 -- Insert and analyze the declaration for the unconstrained base type
8219 New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B');
8222 Make_Full_Type_Declaration (Loc,
8223 Defining_Identifier => New_Base,
8225 Make_Derived_Type_Definition (Loc,
8226 Abstract_Present => Abstract_Present (Type_Def),
8227 Limited_Present => Limited_Present (Type_Def),
8228 Subtype_Indication =>
8229 New_Occurrence_Of (Parent_Base, Loc),
8230 Record_Extension_Part =>
8231 Relocate_Node (Record_Extension_Part (Type_Def)),
8232 Interface_List => Interface_List (Type_Def)));
8234 Set_Parent (New_Decl, Parent (N));
8235 Mark_Rewrite_Insertion (New_Decl);
8236 Insert_Before (N, New_Decl);
8238 -- In the extension case, make sure ancestor is frozen appropriately
8239 -- (see also non-discriminated case below).
8241 if Present (Record_Extension_Part (Type_Def))
8242 or else Is_Interface (Parent_Base)
8244 Freeze_Before (New_Decl, Parent_Type);
8247 -- Note that this call passes False for the Derive_Subps parameter
8248 -- because subprogram derivation is deferred until after creating
8249 -- the subtype (see below).
8252 (New_Decl, Parent_Base, New_Base,
8253 Is_Completion => False, Derive_Subps => False);
8255 -- ??? This needs re-examination to determine whether the
8256 -- above call can simply be replaced by a call to Analyze.
8258 Set_Analyzed (New_Decl);
8260 -- Insert and analyze the declaration for the constrained subtype
8262 if Constraint_Present then
8264 Make_Subtype_Indication (Loc,
8265 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8266 Constraint => Relocate_Node (Constraint (Indic)));
8270 Constr_List : constant List_Id := New_List;
8275 C := First_Elmt (Discriminant_Constraint (Parent_Type));
8276 while Present (C) loop
8279 -- It is safe here to call New_Copy_Tree since we called
8280 -- Force_Evaluation on each constraint previously
8281 -- in Build_Discriminant_Constraints.
8283 Append (New_Copy_Tree (Expr), To => Constr_List);
8289 Make_Subtype_Indication (Loc,
8290 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8292 Make_Index_Or_Discriminant_Constraint (Loc, Constr_List));
8297 Make_Subtype_Declaration (Loc,
8298 Defining_Identifier => Derived_Type,
8299 Subtype_Indication => New_Indic));
8303 -- Derivation of subprograms must be delayed until the full subtype
8304 -- has been established, to ensure proper overriding of subprograms
8305 -- inherited by full types. If the derivations occurred as part of
8306 -- the call to Build_Derived_Type above, then the check for type
8307 -- conformance would fail because earlier primitive subprograms
8308 -- could still refer to the full type prior the change to the new
8309 -- subtype and hence would not match the new base type created here.
8310 -- Subprograms are not derived, however, when Derive_Subps is False
8311 -- (since otherwise there could be redundant derivations).
8313 if Derive_Subps then
8314 Derive_Subprograms (Parent_Type, Derived_Type);
8317 -- For tagged types the Discriminant_Constraint of the new base itype
8318 -- is inherited from the first subtype so that no subtype conformance
8319 -- problem arise when the first subtype overrides primitive
8320 -- operations inherited by the implicit base type.
8323 Set_Discriminant_Constraint
8324 (New_Base, Discriminant_Constraint (Derived_Type));
8330 -- If we get here Derived_Type will have no discriminants or it will be
8331 -- a discriminated unconstrained base type.
8333 -- STEP 1a: perform preliminary actions/checks for derived tagged types
8337 -- The parent type is frozen for non-private extensions (RM 13.14(7))
8338 -- The declaration of a specific descendant of an interface type
8339 -- freezes the interface type (RM 13.14).
8341 if not Private_Extension or else Is_Interface (Parent_Base) then
8342 Freeze_Before (N, Parent_Type);
8345 -- In Ada 2005 (AI-344), the restriction that a derived tagged type
8346 -- cannot be declared at a deeper level than its parent type is
8347 -- removed. The check on derivation within a generic body is also
8348 -- relaxed, but there's a restriction that a derived tagged type
8349 -- cannot be declared in a generic body if it's derived directly
8350 -- or indirectly from a formal type of that generic.
8352 if Ada_Version >= Ada_2005 then
8353 if Present (Enclosing_Generic_Body (Derived_Type)) then
8355 Ancestor_Type : Entity_Id;
8358 -- Check to see if any ancestor of the derived type is a
8361 Ancestor_Type := Parent_Type;
8362 while not Is_Generic_Type (Ancestor_Type)
8363 and then Etype (Ancestor_Type) /= Ancestor_Type
8365 Ancestor_Type := Etype (Ancestor_Type);
8368 -- If the derived type does have a formal type as an
8369 -- ancestor, then it's an error if the derived type is
8370 -- declared within the body of the generic unit that
8371 -- declares the formal type in its generic formal part. It's
8372 -- sufficient to check whether the ancestor type is declared
8373 -- inside the same generic body as the derived type (such as
8374 -- within a nested generic spec), in which case the
8375 -- derivation is legal. If the formal type is declared
8376 -- outside of that generic body, then it's guaranteed that
8377 -- the derived type is declared within the generic body of
8378 -- the generic unit declaring the formal type.
8380 if Is_Generic_Type (Ancestor_Type)
8381 and then Enclosing_Generic_Body (Ancestor_Type) /=
8382 Enclosing_Generic_Body (Derived_Type)
8385 ("parent type of& must not be descendant of formal type"
8386 & " of an enclosing generic body",
8387 Indic, Derived_Type);
8392 elsif Type_Access_Level (Derived_Type) /=
8393 Type_Access_Level (Parent_Type)
8394 and then not Is_Generic_Type (Derived_Type)
8396 if Is_Controlled (Parent_Type) then
8398 ("controlled type must be declared at the library level",
8402 ("type extension at deeper accessibility level than parent",
8408 GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type);
8411 and then GB /= Enclosing_Generic_Body (Parent_Base)
8414 ("parent type of& must not be outside generic body"
8416 Indic, Derived_Type);
8422 -- Ada 2005 (AI-251)
8424 if Ada_Version >= Ada_2005 and then Is_Tagged then
8426 -- "The declaration of a specific descendant of an interface type
8427 -- freezes the interface type" (RM 13.14).
8432 if Is_Non_Empty_List (Interface_List (Type_Def)) then
8433 Iface := First (Interface_List (Type_Def));
8434 while Present (Iface) loop
8435 Freeze_Before (N, Etype (Iface));
8442 -- STEP 1b : preliminary cleanup of the full view of private types
8444 -- If the type is already marked as having discriminants, then it's the
8445 -- completion of a private type or private extension and we need to
8446 -- retain the discriminants from the partial view if the current
8447 -- declaration has Discriminant_Specifications so that we can verify
8448 -- conformance. However, we must remove any existing components that
8449 -- were inherited from the parent (and attached in Copy_And_Swap)
8450 -- because the full type inherits all appropriate components anyway, and
8451 -- we do not want the partial view's components interfering.
8453 if Has_Discriminants (Derived_Type) and then Discriminant_Specs then
8454 Discrim := First_Discriminant (Derived_Type);
8456 Last_Discrim := Discrim;
8457 Next_Discriminant (Discrim);
8458 exit when No (Discrim);
8461 Set_Last_Entity (Derived_Type, Last_Discrim);
8463 -- In all other cases wipe out the list of inherited components (even
8464 -- inherited discriminants), it will be properly rebuilt here.
8467 Set_First_Entity (Derived_Type, Empty);
8468 Set_Last_Entity (Derived_Type, Empty);
8471 -- STEP 1c: Initialize some flags for the Derived_Type
8473 -- The following flags must be initialized here so that
8474 -- Process_Discriminants can check that discriminants of tagged types do
8475 -- not have a default initial value and that access discriminants are
8476 -- only specified for limited records. For completeness, these flags are
8477 -- also initialized along with all the other flags below.
8479 -- AI-419: Limitedness is not inherited from an interface parent, so to
8480 -- be limited in that case the type must be explicitly declared as
8481 -- limited. However, task and protected interfaces are always limited.
8483 if Limited_Present (Type_Def) then
8484 Set_Is_Limited_Record (Derived_Type);
8486 elsif Is_Limited_Record (Parent_Type)
8487 or else (Present (Full_View (Parent_Type))
8488 and then Is_Limited_Record (Full_View (Parent_Type)))
8490 if not Is_Interface (Parent_Type)
8491 or else Is_Synchronized_Interface (Parent_Type)
8492 or else Is_Protected_Interface (Parent_Type)
8493 or else Is_Task_Interface (Parent_Type)
8495 Set_Is_Limited_Record (Derived_Type);
8499 -- STEP 2a: process discriminants of derived type if any
8501 Push_Scope (Derived_Type);
8503 if Discriminant_Specs then
8504 Set_Has_Unknown_Discriminants (Derived_Type, False);
8506 -- The following call initializes fields Has_Discriminants and
8507 -- Discriminant_Constraint, unless we are processing the completion
8508 -- of a private type declaration.
8510 Check_Or_Process_Discriminants (N, Derived_Type);
8512 -- For untagged types, the constraint on the Parent_Type must be
8513 -- present and is used to rename the discriminants.
8515 if not Is_Tagged and then not Has_Discriminants (Parent_Type) then
8516 Error_Msg_N ("untagged parent must have discriminants", Indic);
8518 elsif not Is_Tagged and then not Constraint_Present then
8520 ("discriminant constraint needed for derived untagged records",
8523 -- Otherwise the parent subtype must be constrained unless we have a
8524 -- private extension.
8526 elsif not Constraint_Present
8527 and then not Private_Extension
8528 and then not Is_Constrained (Parent_Type)
8531 ("unconstrained type not allowed in this context", Indic);
8533 elsif Constraint_Present then
8534 -- The following call sets the field Corresponding_Discriminant
8535 -- for the discriminants in the Derived_Type.
8537 Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True);
8539 -- For untagged types all new discriminants must rename
8540 -- discriminants in the parent. For private extensions new
8541 -- discriminants cannot rename old ones (implied by [7.3(13)]).
8543 Discrim := First_Discriminant (Derived_Type);
8544 while Present (Discrim) loop
8546 and then No (Corresponding_Discriminant (Discrim))
8549 ("new discriminants must constrain old ones", Discrim);
8551 elsif Private_Extension
8552 and then Present (Corresponding_Discriminant (Discrim))
8555 ("only static constraints allowed for parent"
8556 & " discriminants in the partial view", Indic);
8560 -- If a new discriminant is used in the constraint, then its
8561 -- subtype must be statically compatible with the parent
8562 -- discriminant's subtype (3.7(15)).
8564 -- However, if the record contains an array constrained by
8565 -- the discriminant but with some different bound, the compiler
8566 -- attemps to create a smaller range for the discriminant type.
8567 -- (See exp_ch3.Adjust_Discriminants). In this case, where
8568 -- the discriminant type is a scalar type, the check must use
8569 -- the original discriminant type in the parent declaration.
8572 Corr_Disc : constant Entity_Id :=
8573 Corresponding_Discriminant (Discrim);
8574 Disc_Type : constant Entity_Id := Etype (Discrim);
8575 Corr_Type : Entity_Id;
8578 if Present (Corr_Disc) then
8579 if Is_Scalar_Type (Disc_Type) then
8581 Entity (Discriminant_Type (Parent (Corr_Disc)));
8583 Corr_Type := Etype (Corr_Disc);
8587 Subtypes_Statically_Compatible (Disc_Type, Corr_Type)
8590 ("subtype must be compatible "
8591 & "with parent discriminant",
8597 Next_Discriminant (Discrim);
8600 -- Check whether the constraints of the full view statically
8601 -- match those imposed by the parent subtype [7.3(13)].
8603 if Present (Stored_Constraint (Derived_Type)) then
8608 C1 := First_Elmt (Discs);
8609 C2 := First_Elmt (Stored_Constraint (Derived_Type));
8610 while Present (C1) and then Present (C2) loop
8612 Fully_Conformant_Expressions (Node (C1), Node (C2))
8615 ("not conformant with previous declaration",
8626 -- STEP 2b: No new discriminants, inherit discriminants if any
8629 if Private_Extension then
8630 Set_Has_Unknown_Discriminants
8632 Has_Unknown_Discriminants (Parent_Type)
8633 or else Unknown_Discriminants_Present (N));
8635 -- The partial view of the parent may have unknown discriminants,
8636 -- but if the full view has discriminants and the parent type is
8637 -- in scope they must be inherited.
8639 elsif Has_Unknown_Discriminants (Parent_Type)
8641 (not Has_Discriminants (Parent_Type)
8642 or else not In_Open_Scopes (Scope (Parent_Type)))
8644 Set_Has_Unknown_Discriminants (Derived_Type);
8647 if not Has_Unknown_Discriminants (Derived_Type)
8648 and then not Has_Unknown_Discriminants (Parent_Base)
8649 and then Has_Discriminants (Parent_Type)
8651 Inherit_Discrims := True;
8652 Set_Has_Discriminants
8653 (Derived_Type, True);
8654 Set_Discriminant_Constraint
8655 (Derived_Type, Discriminant_Constraint (Parent_Base));
8658 -- The following test is true for private types (remember
8659 -- transformation 5. is not applied to those) and in an error
8662 if Constraint_Present then
8663 Discs := Build_Discriminant_Constraints (Parent_Type, Indic);
8666 -- For now mark a new derived type as constrained only if it has no
8667 -- discriminants. At the end of Build_Derived_Record_Type we properly
8668 -- set this flag in the case of private extensions. See comments in
8669 -- point 9. just before body of Build_Derived_Record_Type.
8673 not (Inherit_Discrims
8674 or else Has_Unknown_Discriminants (Derived_Type)));
8677 -- STEP 3: initialize fields of derived type
8679 Set_Is_Tagged_Type (Derived_Type, Is_Tagged);
8680 Set_Stored_Constraint (Derived_Type, No_Elist);
8682 -- Ada 2005 (AI-251): Private type-declarations can implement interfaces
8683 -- but cannot be interfaces
8685 if not Private_Extension
8686 and then Ekind (Derived_Type) /= E_Private_Type
8687 and then Ekind (Derived_Type) /= E_Limited_Private_Type
8689 if Interface_Present (Type_Def) then
8690 Analyze_Interface_Declaration (Derived_Type, Type_Def);
8693 Set_Interfaces (Derived_Type, No_Elist);
8696 -- Fields inherited from the Parent_Type
8698 Set_Has_Specified_Layout
8699 (Derived_Type, Has_Specified_Layout (Parent_Type));
8700 Set_Is_Limited_Composite
8701 (Derived_Type, Is_Limited_Composite (Parent_Type));
8702 Set_Is_Private_Composite
8703 (Derived_Type, Is_Private_Composite (Parent_Type));
8705 if Is_Tagged_Type (Parent_Type) then
8706 Set_No_Tagged_Streams_Pragma
8707 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
8710 -- Fields inherited from the Parent_Base
8712 Set_Has_Controlled_Component
8713 (Derived_Type, Has_Controlled_Component (Parent_Base));
8714 Set_Has_Non_Standard_Rep
8715 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8716 Set_Has_Primitive_Operations
8717 (Derived_Type, Has_Primitive_Operations (Parent_Base));
8719 -- Fields inherited from the Parent_Base in the non-private case
8721 if Ekind (Derived_Type) = E_Record_Type then
8722 Set_Has_Complex_Representation
8723 (Derived_Type, Has_Complex_Representation (Parent_Base));
8726 -- Fields inherited from the Parent_Base for record types
8728 if Is_Record_Type (Derived_Type) then
8730 Parent_Full : Entity_Id;
8733 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
8734 -- Parent_Base can be a private type or private extension. Go
8735 -- to the full view here to get the E_Record_Type specific flags.
8737 if Present (Full_View (Parent_Base)) then
8738 Parent_Full := Full_View (Parent_Base);
8740 Parent_Full := Parent_Base;
8743 Set_OK_To_Reorder_Components
8744 (Derived_Type, OK_To_Reorder_Components (Parent_Full));
8748 -- Set fields for private derived types
8750 if Is_Private_Type (Derived_Type) then
8751 Set_Depends_On_Private (Derived_Type, True);
8752 Set_Private_Dependents (Derived_Type, New_Elmt_List);
8754 -- Inherit fields from non private record types. If this is the
8755 -- completion of a derivation from a private type, the parent itself
8756 -- is private, and the attributes come from its full view, which must
8760 if Is_Private_Type (Parent_Base)
8761 and then not Is_Record_Type (Parent_Base)
8763 Set_Component_Alignment
8764 (Derived_Type, Component_Alignment (Full_View (Parent_Base)));
8766 (Derived_Type, C_Pass_By_Copy (Full_View (Parent_Base)));
8768 Set_Component_Alignment
8769 (Derived_Type, Component_Alignment (Parent_Base));
8771 (Derived_Type, C_Pass_By_Copy (Parent_Base));
8775 -- Set fields for tagged types
8778 Set_Direct_Primitive_Operations (Derived_Type, New_Elmt_List);
8780 -- All tagged types defined in Ada.Finalization are controlled
8782 if Chars (Scope (Derived_Type)) = Name_Finalization
8783 and then Chars (Scope (Scope (Derived_Type))) = Name_Ada
8784 and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard
8786 Set_Is_Controlled (Derived_Type);
8788 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Base));
8791 -- Minor optimization: there is no need to generate the class-wide
8792 -- entity associated with an underlying record view.
8794 if not Is_Underlying_Record_View (Derived_Type) then
8795 Make_Class_Wide_Type (Derived_Type);
8798 Set_Is_Abstract_Type (Derived_Type, Abstract_Present (Type_Def));
8800 if Has_Discriminants (Derived_Type)
8801 and then Constraint_Present
8803 Set_Stored_Constraint
8804 (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs));
8807 if Ada_Version >= Ada_2005 then
8809 Ifaces_List : Elist_Id;
8812 -- Checks rules 3.9.4 (13/2 and 14/2)
8814 if Comes_From_Source (Derived_Type)
8815 and then not Is_Private_Type (Derived_Type)
8816 and then Is_Interface (Parent_Type)
8817 and then not Is_Interface (Derived_Type)
8819 if Is_Task_Interface (Parent_Type) then
8821 ("(Ada 2005) task type required (RM 3.9.4 (13.2))",
8824 elsif Is_Protected_Interface (Parent_Type) then
8826 ("(Ada 2005) protected type required (RM 3.9.4 (14.2))",
8831 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
8833 Check_Interfaces (N, Type_Def);
8835 -- Ada 2005 (AI-251): Collect the list of progenitors that are
8836 -- not already in the parents.
8840 Ifaces_List => Ifaces_List,
8841 Exclude_Parents => True);
8843 Set_Interfaces (Derived_Type, Ifaces_List);
8845 -- If the derived type is the anonymous type created for
8846 -- a declaration whose parent has a constraint, propagate
8847 -- the interface list to the source type. This must be done
8848 -- prior to the completion of the analysis of the source type
8849 -- because the components in the extension may contain current
8850 -- instances whose legality depends on some ancestor.
8852 if Is_Itype (Derived_Type) then
8854 Def : constant Node_Id :=
8855 Associated_Node_For_Itype (Derived_Type);
8858 and then Nkind (Def) = N_Full_Type_Declaration
8861 (Defining_Identifier (Def), Ifaces_List);
8866 -- A derived type inherits any class-wide invariants coming
8867 -- from a parent type or an interface. Note that the invariant
8868 -- procedure of the parent type should not be inherited because
8869 -- the derived type may define invariants of its own.
8871 if Ada_Version >= Ada_2012
8872 and then not Is_Interface (Derived_Type)
8874 if Has_Inherited_Invariants (Parent_Type)
8875 or else Has_Inheritable_Invariants (Parent_Type)
8877 Set_Has_Inherited_Invariants (Derived_Type);
8879 elsif not Is_Empty_Elmt_List (Ifaces_List) then
8882 Iface_Elmt : Elmt_Id;
8885 Iface_Elmt := First_Elmt (Ifaces_List);
8886 while Present (Iface_Elmt) loop
8887 Iface := Node (Iface_Elmt);
8889 if Has_Inheritable_Invariants (Iface) then
8890 Set_Has_Inherited_Invariants (Derived_Type);
8894 Next_Elmt (Iface_Elmt);
8900 -- A type extension is automatically Ghost when one of its
8901 -- progenitors is Ghost (SPARK RM 6.9(9)). This property is
8902 -- also inherited when the parent type is Ghost, but this is
8903 -- done in Build_Derived_Type as the mechanism also handles
8904 -- untagged derivations.
8906 if Implements_Ghost_Interface (Derived_Type) then
8907 Set_Is_Ghost_Entity (Derived_Type);
8913 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Base));
8914 Set_Has_Non_Standard_Rep
8915 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8918 -- STEP 4: Inherit components from the parent base and constrain them.
8919 -- Apply the second transformation described in point 6. above.
8921 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
8922 or else not Has_Discriminants (Parent_Type)
8923 or else not Is_Constrained (Parent_Type)
8927 Constrs := Discriminant_Constraint (Parent_Type);
8932 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
8934 -- STEP 5a: Copy the parent record declaration for untagged types
8936 if not Is_Tagged then
8938 -- Discriminant_Constraint (Derived_Type) has been properly
8939 -- constructed. Save it and temporarily set it to Empty because we
8940 -- do not want the call to New_Copy_Tree below to mess this list.
8942 if Has_Discriminants (Derived_Type) then
8943 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
8944 Set_Discriminant_Constraint (Derived_Type, No_Elist);
8946 Save_Discr_Constr := No_Elist;
8949 -- Save the Etype field of Derived_Type. It is correctly set now,
8950 -- but the call to New_Copy tree may remap it to point to itself,
8951 -- which is not what we want. Ditto for the Next_Entity field.
8953 Save_Etype := Etype (Derived_Type);
8954 Save_Next_Entity := Next_Entity (Derived_Type);
8956 -- Assoc_List maps all stored discriminants in the Parent_Base to
8957 -- stored discriminants in the Derived_Type. It is fundamental that
8958 -- no types or itypes with discriminants other than the stored
8959 -- discriminants appear in the entities declared inside
8960 -- Derived_Type, since the back end cannot deal with it.
8964 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
8966 -- Restore the fields saved prior to the New_Copy_Tree call
8967 -- and compute the stored constraint.
8969 Set_Etype (Derived_Type, Save_Etype);
8970 Set_Next_Entity (Derived_Type, Save_Next_Entity);
8972 if Has_Discriminants (Derived_Type) then
8973 Set_Discriminant_Constraint
8974 (Derived_Type, Save_Discr_Constr);
8975 Set_Stored_Constraint
8976 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
8977 Replace_Components (Derived_Type, New_Decl);
8978 Set_Has_Implicit_Dereference
8979 (Derived_Type, Has_Implicit_Dereference (Parent_Type));
8982 -- Insert the new derived type declaration
8984 Rewrite (N, New_Decl);
8986 -- STEP 5b: Complete the processing for record extensions in generics
8988 -- There is no completion for record extensions declared in the
8989 -- parameter part of a generic, so we need to complete processing for
8990 -- these generic record extensions here. The Record_Type_Definition call
8991 -- will change the Ekind of the components from E_Void to E_Component.
8993 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
8994 Record_Type_Definition (Empty, Derived_Type);
8996 -- STEP 5c: Process the record extension for non private tagged types
8998 elsif not Private_Extension then
8999 Expand_Record_Extension (Derived_Type, Type_Def);
9001 -- Note : previously in ASIS mode we set the Parent_Subtype of the
9002 -- derived type to propagate some semantic information. This led
9003 -- to other ASIS failures and has been removed.
9005 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
9006 -- implemented interfaces if we are in expansion mode
9009 and then Has_Interfaces (Derived_Type)
9011 Add_Interface_Tag_Components (N, Derived_Type);
9014 -- Analyze the record extension
9016 Record_Type_Definition
9017 (Record_Extension_Part (Type_Def), Derived_Type);
9022 -- Nothing else to do if there is an error in the derivation.
9023 -- An unusual case: the full view may be derived from a type in an
9024 -- instance, when the partial view was used illegally as an actual
9025 -- in that instance, leading to a circular definition.
9027 if Etype (Derived_Type) = Any_Type
9028 or else Etype (Parent_Type) = Derived_Type
9033 -- Set delayed freeze and then derive subprograms, we need to do
9034 -- this in this order so that derived subprograms inherit the
9035 -- derived freeze if necessary.
9037 Set_Has_Delayed_Freeze (Derived_Type);
9039 if Derive_Subps then
9040 Derive_Subprograms (Parent_Type, Derived_Type);
9043 -- If we have a private extension which defines a constrained derived
9044 -- type mark as constrained here after we have derived subprograms. See
9045 -- comment on point 9. just above the body of Build_Derived_Record_Type.
9047 if Private_Extension and then Inherit_Discrims then
9048 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
9049 Set_Is_Constrained (Derived_Type, True);
9050 Set_Discriminant_Constraint (Derived_Type, Discs);
9052 elsif Is_Constrained (Parent_Type) then
9054 (Derived_Type, True);
9055 Set_Discriminant_Constraint
9056 (Derived_Type, Discriminant_Constraint (Parent_Type));
9060 -- Update the class-wide type, which shares the now-completed entity
9061 -- list with its specific type. In case of underlying record views,
9062 -- we do not generate the corresponding class wide entity.
9065 and then not Is_Underlying_Record_View (Derived_Type)
9068 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
9070 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
9073 Check_Function_Writable_Actuals (N);
9074 end Build_Derived_Record_Type;
9076 ------------------------
9077 -- Build_Derived_Type --
9078 ------------------------
9080 procedure Build_Derived_Type
9082 Parent_Type : Entity_Id;
9083 Derived_Type : Entity_Id;
9084 Is_Completion : Boolean;
9085 Derive_Subps : Boolean := True)
9087 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
9090 -- Set common attributes
9092 Set_Scope (Derived_Type, Current_Scope);
9094 Set_Etype (Derived_Type, Parent_Base);
9095 Set_Ekind (Derived_Type, Ekind (Parent_Base));
9096 Propagate_Concurrent_Flags (Derived_Type, Parent_Base);
9098 Set_Size_Info (Derived_Type, Parent_Type);
9099 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
9100 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
9101 Set_Disable_Controlled (Derived_Type, Disable_Controlled (Parent_Type));
9103 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
9104 Set_Is_Volatile (Derived_Type, Is_Volatile (Parent_Type));
9106 if Is_Tagged_Type (Derived_Type) then
9107 Set_No_Tagged_Streams_Pragma
9108 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
9111 -- If the parent has primitive routines, set the derived type link
9113 if Has_Primitive_Operations (Parent_Type) then
9114 Set_Derived_Type_Link (Parent_Base, Derived_Type);
9117 -- If the parent type is a private subtype, the convention on the base
9118 -- type may be set in the private part, and not propagated to the
9119 -- subtype until later, so we obtain the convention from the base type.
9121 Set_Convention (Derived_Type, Convention (Parent_Base));
9123 -- Set SSO default for record or array type
9125 if (Is_Array_Type (Derived_Type) or else Is_Record_Type (Derived_Type))
9126 and then Is_Base_Type (Derived_Type)
9128 Set_Default_SSO (Derived_Type);
9131 -- Propagate invariant information. The new type has invariants if
9132 -- they are inherited from the parent type, and these invariants can
9133 -- be further inherited, so both flags are set.
9135 -- We similarly inherit predicates
9137 if Has_Predicates (Parent_Type) then
9138 Set_Has_Predicates (Derived_Type);
9141 -- The derived type inherits the representation clauses of the parent
9143 Inherit_Rep_Item_Chain (Derived_Type, Parent_Type);
9145 -- Propagate the attributes related to pragma Default_Initial_Condition
9146 -- from the parent type to the private extension. A derived type always
9147 -- inherits the default initial condition flag from the parent type. If
9148 -- the derived type carries its own Default_Initial_Condition pragma,
9149 -- the flag is later reset in Analyze_Pragma. Note that both flags are
9150 -- mutually exclusive.
9152 Propagate_Default_Init_Cond_Attributes
9153 (From_Typ => Parent_Type,
9154 To_Typ => Derived_Type,
9155 Parent_To_Derivation => True);
9157 -- If the parent type has delayed rep aspects, then mark the derived
9158 -- type as possibly inheriting a delayed rep aspect.
9160 if Has_Delayed_Rep_Aspects (Parent_Type) then
9161 Set_May_Inherit_Delayed_Rep_Aspects (Derived_Type);
9164 -- Propagate the attributes related to pragma Ghost from the parent type
9165 -- to the derived type or type extension (SPARK RM 6.9(9)).
9167 if Is_Ghost_Entity (Parent_Type) then
9168 Set_Is_Ghost_Entity (Derived_Type);
9171 -- Type dependent processing
9173 case Ekind (Parent_Type) is
9174 when Numeric_Kind =>
9175 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
9178 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
9182 | Class_Wide_Kind =>
9183 Build_Derived_Record_Type
9184 (N, Parent_Type, Derived_Type, Derive_Subps);
9187 when Enumeration_Kind =>
9188 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
9191 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
9193 when Incomplete_Or_Private_Kind =>
9194 Build_Derived_Private_Type
9195 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
9197 -- For discriminated types, the derivation includes deriving
9198 -- primitive operations. For others it is done below.
9200 if Is_Tagged_Type (Parent_Type)
9201 or else Has_Discriminants (Parent_Type)
9202 or else (Present (Full_View (Parent_Type))
9203 and then Has_Discriminants (Full_View (Parent_Type)))
9208 when Concurrent_Kind =>
9209 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
9212 raise Program_Error;
9215 -- Nothing more to do if some error occurred
9217 if Etype (Derived_Type) = Any_Type then
9221 -- Set delayed freeze and then derive subprograms, we need to do this
9222 -- in this order so that derived subprograms inherit the derived freeze
9225 Set_Has_Delayed_Freeze (Derived_Type);
9227 if Derive_Subps then
9228 Derive_Subprograms (Parent_Type, Derived_Type);
9231 Set_Has_Primitive_Operations
9232 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
9233 end Build_Derived_Type;
9235 -----------------------
9236 -- Build_Discriminal --
9237 -----------------------
9239 procedure Build_Discriminal (Discrim : Entity_Id) is
9240 D_Minal : Entity_Id;
9241 CR_Disc : Entity_Id;
9244 -- A discriminal has the same name as the discriminant
9246 D_Minal := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
9248 Set_Ekind (D_Minal, E_In_Parameter);
9249 Set_Mechanism (D_Minal, Default_Mechanism);
9250 Set_Etype (D_Minal, Etype (Discrim));
9251 Set_Scope (D_Minal, Current_Scope);
9252 Set_Parent (D_Minal, Parent (Discrim));
9254 Set_Discriminal (Discrim, D_Minal);
9255 Set_Discriminal_Link (D_Minal, Discrim);
9257 -- For task types, build at once the discriminants of the corresponding
9258 -- record, which are needed if discriminants are used in entry defaults
9259 -- and in family bounds.
9261 if Is_Concurrent_Type (Current_Scope)
9263 Is_Limited_Type (Current_Scope)
9265 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
9267 Set_Ekind (CR_Disc, E_In_Parameter);
9268 Set_Mechanism (CR_Disc, Default_Mechanism);
9269 Set_Etype (CR_Disc, Etype (Discrim));
9270 Set_Scope (CR_Disc, Current_Scope);
9271 Set_Discriminal_Link (CR_Disc, Discrim);
9272 Set_CR_Discriminant (Discrim, CR_Disc);
9274 end Build_Discriminal;
9276 ------------------------------------
9277 -- Build_Discriminant_Constraints --
9278 ------------------------------------
9280 function Build_Discriminant_Constraints
9283 Derived_Def : Boolean := False) return Elist_Id
9285 C : constant Node_Id := Constraint (Def);
9286 Nb_Discr : constant Nat := Number_Discriminants (T);
9288 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
9289 -- Saves the expression corresponding to a given discriminant in T
9291 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
9292 -- Return the Position number within array Discr_Expr of a discriminant
9293 -- D within the discriminant list of the discriminated type T.
9295 procedure Process_Discriminant_Expression
9298 -- If this is a discriminant constraint on a partial view, do not
9299 -- generate an overflow check on the discriminant expression. The check
9300 -- will be generated when constraining the full view. Otherwise the
9301 -- backend creates duplicate symbols for the temporaries corresponding
9302 -- to the expressions to be checked, causing spurious assembler errors.
9308 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
9312 Disc := First_Discriminant (T);
9313 for J in Discr_Expr'Range loop
9318 Next_Discriminant (Disc);
9321 -- Note: Since this function is called on discriminants that are
9322 -- known to belong to the discriminated type, falling through the
9323 -- loop with no match signals an internal compiler error.
9325 raise Program_Error;
9328 -------------------------------------
9329 -- Process_Discriminant_Expression --
9330 -------------------------------------
9332 procedure Process_Discriminant_Expression
9336 BDT : constant Entity_Id := Base_Type (Etype (D));
9339 -- If this is a discriminant constraint on a partial view, do
9340 -- not generate an overflow on the discriminant expression. The
9341 -- check will be generated when constraining the full view.
9343 if Is_Private_Type (T)
9344 and then Present (Full_View (T))
9346 Analyze_And_Resolve (Expr, BDT, Suppress => Overflow_Check);
9348 Analyze_And_Resolve (Expr, BDT);
9350 end Process_Discriminant_Expression;
9352 -- Declarations local to Build_Discriminant_Constraints
9356 Elist : constant Elist_Id := New_Elmt_List;
9364 Discrim_Present : Boolean := False;
9366 -- Start of processing for Build_Discriminant_Constraints
9369 -- The following loop will process positional associations only.
9370 -- For a positional association, the (single) discriminant is
9371 -- implicitly specified by position, in textual order (RM 3.7.2).
9373 Discr := First_Discriminant (T);
9374 Constr := First (Constraints (C));
9375 for D in Discr_Expr'Range loop
9376 exit when Nkind (Constr) = N_Discriminant_Association;
9379 Error_Msg_N ("too few discriminants given in constraint", C);
9380 return New_Elmt_List;
9382 elsif Nkind (Constr) = N_Range
9383 or else (Nkind (Constr) = N_Attribute_Reference
9384 and then Attribute_Name (Constr) = Name_Range)
9387 ("a range is not a valid discriminant constraint", Constr);
9388 Discr_Expr (D) := Error;
9391 Process_Discriminant_Expression (Constr, Discr);
9392 Discr_Expr (D) := Constr;
9395 Next_Discriminant (Discr);
9399 if No (Discr) and then Present (Constr) then
9400 Error_Msg_N ("too many discriminants given in constraint", Constr);
9401 return New_Elmt_List;
9404 -- Named associations can be given in any order, but if both positional
9405 -- and named associations are used in the same discriminant constraint,
9406 -- then positional associations must occur first, at their normal
9407 -- position. Hence once a named association is used, the rest of the
9408 -- discriminant constraint must use only named associations.
9410 while Present (Constr) loop
9412 -- Positional association forbidden after a named association
9414 if Nkind (Constr) /= N_Discriminant_Association then
9415 Error_Msg_N ("positional association follows named one", Constr);
9416 return New_Elmt_List;
9418 -- Otherwise it is a named association
9421 -- E records the type of the discriminants in the named
9422 -- association. All the discriminants specified in the same name
9423 -- association must have the same type.
9427 -- Search the list of discriminants in T to see if the simple name
9428 -- given in the constraint matches any of them.
9430 Id := First (Selector_Names (Constr));
9431 while Present (Id) loop
9434 -- If Original_Discriminant is present, we are processing a
9435 -- generic instantiation and this is an instance node. We need
9436 -- to find the name of the corresponding discriminant in the
9437 -- actual record type T and not the name of the discriminant in
9438 -- the generic formal. Example:
9441 -- type G (D : int) is private;
9443 -- subtype W is G (D => 1);
9445 -- type Rec (X : int) is record ... end record;
9446 -- package Q is new P (G => Rec);
9448 -- At the point of the instantiation, formal type G is Rec
9449 -- and therefore when reanalyzing "subtype W is G (D => 1);"
9450 -- which really looks like "subtype W is Rec (D => 1);" at
9451 -- the point of instantiation, we want to find the discriminant
9452 -- that corresponds to D in Rec, i.e. X.
9454 if Present (Original_Discriminant (Id))
9455 and then In_Instance
9457 Discr := Find_Corresponding_Discriminant (Id, T);
9461 Discr := First_Discriminant (T);
9462 while Present (Discr) loop
9463 if Chars (Discr) = Chars (Id) then
9468 Next_Discriminant (Discr);
9472 Error_Msg_N ("& does not match any discriminant", Id);
9473 return New_Elmt_List;
9475 -- If the parent type is a generic formal, preserve the
9476 -- name of the discriminant for subsequent instances.
9477 -- see comment at the beginning of this if statement.
9479 elsif Is_Generic_Type (Root_Type (T)) then
9480 Set_Original_Discriminant (Id, Discr);
9484 Position := Pos_Of_Discr (T, Discr);
9486 if Present (Discr_Expr (Position)) then
9487 Error_Msg_N ("duplicate constraint for discriminant&", Id);
9490 -- Each discriminant specified in the same named association
9491 -- must be associated with a separate copy of the
9492 -- corresponding expression.
9494 if Present (Next (Id)) then
9495 Expr := New_Copy_Tree (Expression (Constr));
9496 Set_Parent (Expr, Parent (Expression (Constr)));
9498 Expr := Expression (Constr);
9501 Discr_Expr (Position) := Expr;
9502 Process_Discriminant_Expression (Expr, Discr);
9505 -- A discriminant association with more than one discriminant
9506 -- name is only allowed if the named discriminants are all of
9507 -- the same type (RM 3.7.1(8)).
9510 E := Base_Type (Etype (Discr));
9512 elsif Base_Type (Etype (Discr)) /= E then
9514 ("all discriminants in an association " &
9515 "must have the same type", Id);
9525 -- A discriminant constraint must provide exactly one value for each
9526 -- discriminant of the type (RM 3.7.1(8)).
9528 for J in Discr_Expr'Range loop
9529 if No (Discr_Expr (J)) then
9530 Error_Msg_N ("too few discriminants given in constraint", C);
9531 return New_Elmt_List;
9535 -- Determine if there are discriminant expressions in the constraint
9537 for J in Discr_Expr'Range loop
9538 if Denotes_Discriminant
9539 (Discr_Expr (J), Check_Concurrent => True)
9541 Discrim_Present := True;
9545 -- Build an element list consisting of the expressions given in the
9546 -- discriminant constraint and apply the appropriate checks. The list
9547 -- is constructed after resolving any named discriminant associations
9548 -- and therefore the expressions appear in the textual order of the
9551 Discr := First_Discriminant (T);
9552 for J in Discr_Expr'Range loop
9553 if Discr_Expr (J) /= Error then
9554 Append_Elmt (Discr_Expr (J), Elist);
9556 -- If any of the discriminant constraints is given by a
9557 -- discriminant and we are in a derived type declaration we
9558 -- have a discriminant renaming. Establish link between new
9559 -- and old discriminant.
9561 if Denotes_Discriminant (Discr_Expr (J)) then
9563 Set_Corresponding_Discriminant
9564 (Entity (Discr_Expr (J)), Discr);
9567 -- Force the evaluation of non-discriminant expressions.
9568 -- If we have found a discriminant in the constraint 3.4(26)
9569 -- and 3.8(18) demand that no range checks are performed are
9570 -- after evaluation. If the constraint is for a component
9571 -- definition that has a per-object constraint, expressions are
9572 -- evaluated but not checked either. In all other cases perform
9576 if Discrim_Present then
9579 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
9581 Has_Per_Object_Constraint
9582 (Defining_Identifier (Parent (Parent (Def))))
9586 elsif Is_Access_Type (Etype (Discr)) then
9587 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
9590 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
9593 Force_Evaluation (Discr_Expr (J));
9596 -- Check that the designated type of an access discriminant's
9597 -- expression is not a class-wide type unless the discriminant's
9598 -- designated type is also class-wide.
9600 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
9601 and then not Is_Class_Wide_Type
9602 (Designated_Type (Etype (Discr)))
9603 and then Etype (Discr_Expr (J)) /= Any_Type
9604 and then Is_Class_Wide_Type
9605 (Designated_Type (Etype (Discr_Expr (J))))
9607 Wrong_Type (Discr_Expr (J), Etype (Discr));
9609 elsif Is_Access_Type (Etype (Discr))
9610 and then not Is_Access_Constant (Etype (Discr))
9611 and then Is_Access_Type (Etype (Discr_Expr (J)))
9612 and then Is_Access_Constant (Etype (Discr_Expr (J)))
9615 ("constraint for discriminant& must be access to variable",
9620 Next_Discriminant (Discr);
9624 end Build_Discriminant_Constraints;
9626 ---------------------------------
9627 -- Build_Discriminated_Subtype --
9628 ---------------------------------
9630 procedure Build_Discriminated_Subtype
9634 Related_Nod : Node_Id;
9635 For_Access : Boolean := False)
9637 Has_Discrs : constant Boolean := Has_Discriminants (T);
9638 Constrained : constant Boolean :=
9640 and then not Is_Empty_Elmt_List (Elist)
9641 and then not Is_Class_Wide_Type (T))
9642 or else Is_Constrained (T);
9645 if Ekind (T) = E_Record_Type then
9647 Set_Ekind (Def_Id, E_Private_Subtype);
9648 Set_Is_For_Access_Subtype (Def_Id, True);
9650 Set_Ekind (Def_Id, E_Record_Subtype);
9653 -- Inherit preelaboration flag from base, for types for which it
9654 -- may have been set: records, private types, protected types.
9656 Set_Known_To_Have_Preelab_Init
9657 (Def_Id, Known_To_Have_Preelab_Init (T));
9659 elsif Ekind (T) = E_Task_Type then
9660 Set_Ekind (Def_Id, E_Task_Subtype);
9662 elsif Ekind (T) = E_Protected_Type then
9663 Set_Ekind (Def_Id, E_Protected_Subtype);
9664 Set_Known_To_Have_Preelab_Init
9665 (Def_Id, Known_To_Have_Preelab_Init (T));
9667 elsif Is_Private_Type (T) then
9668 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
9669 Set_Known_To_Have_Preelab_Init
9670 (Def_Id, Known_To_Have_Preelab_Init (T));
9672 -- Private subtypes may have private dependents
9674 Set_Private_Dependents (Def_Id, New_Elmt_List);
9676 elsif Is_Class_Wide_Type (T) then
9677 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
9680 -- Incomplete type. Attach subtype to list of dependents, to be
9681 -- completed with full view of parent type, unless is it the
9682 -- designated subtype of a record component within an init_proc.
9683 -- This last case arises for a component of an access type whose
9684 -- designated type is incomplete (e.g. a Taft Amendment type).
9685 -- The designated subtype is within an inner scope, and needs no
9686 -- elaboration, because only the access type is needed in the
9687 -- initialization procedure.
9689 Set_Ekind (Def_Id, Ekind (T));
9691 if For_Access and then Within_Init_Proc then
9694 Append_Elmt (Def_Id, Private_Dependents (T));
9698 Set_Etype (Def_Id, T);
9699 Init_Size_Align (Def_Id);
9700 Set_Has_Discriminants (Def_Id, Has_Discrs);
9701 Set_Is_Constrained (Def_Id, Constrained);
9703 Set_First_Entity (Def_Id, First_Entity (T));
9704 Set_Last_Entity (Def_Id, Last_Entity (T));
9705 Set_Has_Implicit_Dereference
9706 (Def_Id, Has_Implicit_Dereference (T));
9708 -- If the subtype is the completion of a private declaration, there may
9709 -- have been representation clauses for the partial view, and they must
9710 -- be preserved. Build_Derived_Type chains the inherited clauses with
9711 -- the ones appearing on the extension. If this comes from a subtype
9712 -- declaration, all clauses are inherited.
9714 if No (First_Rep_Item (Def_Id)) then
9715 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
9718 if Is_Tagged_Type (T) then
9719 Set_Is_Tagged_Type (Def_Id);
9720 Set_No_Tagged_Streams_Pragma (Def_Id, No_Tagged_Streams_Pragma (T));
9721 Make_Class_Wide_Type (Def_Id);
9724 Set_Stored_Constraint (Def_Id, No_Elist);
9727 Set_Discriminant_Constraint (Def_Id, Elist);
9728 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
9731 if Is_Tagged_Type (T) then
9733 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
9734 -- concurrent record type (which has the list of primitive
9737 if Ada_Version >= Ada_2005
9738 and then Is_Concurrent_Type (T)
9740 Set_Corresponding_Record_Type (Def_Id,
9741 Corresponding_Record_Type (T));
9743 Set_Direct_Primitive_Operations (Def_Id,
9744 Direct_Primitive_Operations (T));
9747 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
9750 -- Subtypes introduced by component declarations do not need to be
9751 -- marked as delayed, and do not get freeze nodes, because the semantics
9752 -- verifies that the parents of the subtypes are frozen before the
9753 -- enclosing record is frozen.
9755 if not Is_Type (Scope (Def_Id)) then
9756 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
9758 if Is_Private_Type (T)
9759 and then Present (Full_View (T))
9761 Conditional_Delay (Def_Id, Full_View (T));
9763 Conditional_Delay (Def_Id, T);
9767 if Is_Record_Type (T) then
9768 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
9771 and then not Is_Empty_Elmt_List (Elist)
9772 and then not For_Access
9774 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
9775 elsif not For_Access then
9776 Set_Cloned_Subtype (Def_Id, T);
9779 end Build_Discriminated_Subtype;
9781 ---------------------------
9782 -- Build_Itype_Reference --
9783 ---------------------------
9785 procedure Build_Itype_Reference
9789 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
9792 -- Itype references are only created for use by the back-end
9794 if Inside_A_Generic then
9797 Set_Itype (IR, Ityp);
9798 Insert_After (Nod, IR);
9800 end Build_Itype_Reference;
9802 ------------------------
9803 -- Build_Scalar_Bound --
9804 ------------------------
9806 function Build_Scalar_Bound
9809 Der_T : Entity_Id) return Node_Id
9811 New_Bound : Entity_Id;
9814 -- Note: not clear why this is needed, how can the original bound
9815 -- be unanalyzed at this point? and if it is, what business do we
9816 -- have messing around with it? and why is the base type of the
9817 -- parent type the right type for the resolution. It probably is
9818 -- not. It is OK for the new bound we are creating, but not for
9819 -- the old one??? Still if it never happens, no problem.
9821 Analyze_And_Resolve (Bound, Base_Type (Par_T));
9823 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
9824 New_Bound := New_Copy (Bound);
9825 Set_Etype (New_Bound, Der_T);
9826 Set_Analyzed (New_Bound);
9828 elsif Is_Entity_Name (Bound) then
9829 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
9831 -- The following is almost certainly wrong. What business do we have
9832 -- relocating a node (Bound) that is presumably still attached to
9833 -- the tree elsewhere???
9836 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
9839 Set_Etype (New_Bound, Der_T);
9841 end Build_Scalar_Bound;
9843 --------------------------------
9844 -- Build_Underlying_Full_View --
9845 --------------------------------
9847 procedure Build_Underlying_Full_View
9852 Loc : constant Source_Ptr := Sloc (N);
9853 Subt : constant Entity_Id :=
9854 Make_Defining_Identifier
9855 (Loc, New_External_Name (Chars (Typ), 'S'));
9862 procedure Set_Discriminant_Name (Id : Node_Id);
9863 -- If the derived type has discriminants, they may rename discriminants
9864 -- of the parent. When building the full view of the parent, we need to
9865 -- recover the names of the original discriminants if the constraint is
9866 -- given by named associations.
9868 ---------------------------
9869 -- Set_Discriminant_Name --
9870 ---------------------------
9872 procedure Set_Discriminant_Name (Id : Node_Id) is
9876 Set_Original_Discriminant (Id, Empty);
9878 if Has_Discriminants (Typ) then
9879 Disc := First_Discriminant (Typ);
9880 while Present (Disc) loop
9881 if Chars (Disc) = Chars (Id)
9882 and then Present (Corresponding_Discriminant (Disc))
9884 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
9886 Next_Discriminant (Disc);
9889 end Set_Discriminant_Name;
9891 -- Start of processing for Build_Underlying_Full_View
9894 if Nkind (N) = N_Full_Type_Declaration then
9895 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
9897 elsif Nkind (N) = N_Subtype_Declaration then
9898 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
9900 elsif Nkind (N) = N_Component_Declaration then
9903 (Constraint (Subtype_Indication (Component_Definition (N))));
9906 raise Program_Error;
9909 C := First (Constraints (Constr));
9910 while Present (C) loop
9911 if Nkind (C) = N_Discriminant_Association then
9912 Id := First (Selector_Names (C));
9913 while Present (Id) loop
9914 Set_Discriminant_Name (Id);
9923 Make_Subtype_Declaration (Loc,
9924 Defining_Identifier => Subt,
9925 Subtype_Indication =>
9926 Make_Subtype_Indication (Loc,
9927 Subtype_Mark => New_Occurrence_Of (Par, Loc),
9928 Constraint => New_Copy_Tree (Constr)));
9930 -- If this is a component subtype for an outer itype, it is not
9931 -- a list member, so simply set the parent link for analysis: if
9932 -- the enclosing type does not need to be in a declarative list,
9933 -- neither do the components.
9935 if Is_List_Member (N)
9936 and then Nkind (N) /= N_Component_Declaration
9938 Insert_Before (N, Indic);
9940 Set_Parent (Indic, Parent (N));
9944 Set_Underlying_Full_View (Typ, Full_View (Subt));
9945 end Build_Underlying_Full_View;
9947 -------------------------------
9948 -- Check_Abstract_Overriding --
9949 -------------------------------
9951 procedure Check_Abstract_Overriding (T : Entity_Id) is
9952 Alias_Subp : Entity_Id;
9958 procedure Check_Pragma_Implemented (Subp : Entity_Id);
9959 -- Ada 2012 (AI05-0030): Subprogram Subp overrides an interface routine
9960 -- which has pragma Implemented already set. Check whether Subp's entity
9961 -- kind conforms to the implementation kind of the overridden routine.
9963 procedure Check_Pragma_Implemented
9965 Iface_Subp : Entity_Id);
9966 -- Ada 2012 (AI05-0030): Subprogram Subp overrides interface routine
9967 -- Iface_Subp and both entities have pragma Implemented already set on
9968 -- them. Check whether the two implementation kinds are conforming.
9970 procedure Inherit_Pragma_Implemented
9972 Iface_Subp : Entity_Id);
9973 -- Ada 2012 (AI05-0030): Interface primitive Subp overrides interface
9974 -- subprogram Iface_Subp which has been marked by pragma Implemented.
9975 -- Propagate the implementation kind of Iface_Subp to Subp.
9977 ------------------------------
9978 -- Check_Pragma_Implemented --
9979 ------------------------------
9981 procedure Check_Pragma_Implemented (Subp : Entity_Id) is
9982 Iface_Alias : constant Entity_Id := Interface_Alias (Subp);
9983 Impl_Kind : constant Name_Id := Implementation_Kind (Iface_Alias);
9984 Subp_Alias : constant Entity_Id := Alias (Subp);
9985 Contr_Typ : Entity_Id;
9986 Impl_Subp : Entity_Id;
9989 -- Subp must have an alias since it is a hidden entity used to link
9990 -- an interface subprogram to its overriding counterpart.
9992 pragma Assert (Present (Subp_Alias));
9994 -- Handle aliases to synchronized wrappers
9996 Impl_Subp := Subp_Alias;
9998 if Is_Primitive_Wrapper (Impl_Subp) then
9999 Impl_Subp := Wrapped_Entity (Impl_Subp);
10002 -- Extract the type of the controlling formal
10004 Contr_Typ := Etype (First_Formal (Subp_Alias));
10006 if Is_Concurrent_Record_Type (Contr_Typ) then
10007 Contr_Typ := Corresponding_Concurrent_Type (Contr_Typ);
10010 -- An interface subprogram whose implementation kind is By_Entry must
10011 -- be implemented by an entry.
10013 if Impl_Kind = Name_By_Entry
10014 and then Ekind (Impl_Subp) /= E_Entry
10016 Error_Msg_Node_2 := Iface_Alias;
10018 ("type & must implement abstract subprogram & with an entry",
10019 Subp_Alias, Contr_Typ);
10021 elsif Impl_Kind = Name_By_Protected_Procedure then
10023 -- An interface subprogram whose implementation kind is By_
10024 -- Protected_Procedure cannot be implemented by a primitive
10025 -- procedure of a task type.
10027 if Ekind (Contr_Typ) /= E_Protected_Type then
10028 Error_Msg_Node_2 := Contr_Typ;
10030 ("interface subprogram & cannot be implemented by a " &
10031 "primitive procedure of task type &", Subp_Alias,
10034 -- An interface subprogram whose implementation kind is By_
10035 -- Protected_Procedure must be implemented by a procedure.
10037 elsif Ekind (Impl_Subp) /= E_Procedure then
10038 Error_Msg_Node_2 := Iface_Alias;
10040 ("type & must implement abstract subprogram & with a " &
10041 "procedure", Subp_Alias, Contr_Typ);
10043 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
10044 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
10046 Error_Msg_Name_1 := Impl_Kind;
10048 ("overriding operation& must have synchronization%",
10052 -- If primitive has Optional synchronization, overriding operation
10053 -- must match if it has an explicit synchronization..
10055 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
10056 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
10058 Error_Msg_Name_1 := Impl_Kind;
10060 ("overriding operation& must have syncrhonization%",
10063 end Check_Pragma_Implemented;
10065 ------------------------------
10066 -- Check_Pragma_Implemented --
10067 ------------------------------
10069 procedure Check_Pragma_Implemented
10071 Iface_Subp : Entity_Id)
10073 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
10074 Subp_Kind : constant Name_Id := Implementation_Kind (Subp);
10077 -- Ada 2012 (AI05-0030): The implementation kinds of an overridden
10078 -- and overriding subprogram are different. In general this is an
10079 -- error except when the implementation kind of the overridden
10080 -- subprograms is By_Any or Optional.
10082 if Iface_Kind /= Subp_Kind
10083 and then Iface_Kind /= Name_By_Any
10084 and then Iface_Kind /= Name_Optional
10086 if Iface_Kind = Name_By_Entry then
10088 ("incompatible implementation kind, overridden subprogram " &
10089 "is marked By_Entry", Subp);
10092 ("incompatible implementation kind, overridden subprogram " &
10093 "is marked By_Protected_Procedure", Subp);
10096 end Check_Pragma_Implemented;
10098 --------------------------------
10099 -- Inherit_Pragma_Implemented --
10100 --------------------------------
10102 procedure Inherit_Pragma_Implemented
10104 Iface_Subp : Entity_Id)
10106 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
10107 Loc : constant Source_Ptr := Sloc (Subp);
10108 Impl_Prag : Node_Id;
10111 -- Since the implementation kind is stored as a representation item
10112 -- rather than a flag, create a pragma node.
10116 Chars => Name_Implemented,
10117 Pragma_Argument_Associations => New_List (
10118 Make_Pragma_Argument_Association (Loc,
10119 Expression => New_Occurrence_Of (Subp, Loc)),
10121 Make_Pragma_Argument_Association (Loc,
10122 Expression => Make_Identifier (Loc, Iface_Kind))));
10124 -- The pragma doesn't need to be analyzed because it is internally
10125 -- built. It is safe to directly register it as a rep item since we
10126 -- are only interested in the characters of the implementation kind.
10128 Record_Rep_Item (Subp, Impl_Prag);
10129 end Inherit_Pragma_Implemented;
10131 -- Start of processing for Check_Abstract_Overriding
10134 Op_List := Primitive_Operations (T);
10136 -- Loop to check primitive operations
10138 Elmt := First_Elmt (Op_List);
10139 while Present (Elmt) loop
10140 Subp := Node (Elmt);
10141 Alias_Subp := Alias (Subp);
10143 -- Inherited subprograms are identified by the fact that they do not
10144 -- come from source, and the associated source location is the
10145 -- location of the first subtype of the derived type.
10147 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
10148 -- subprograms that "require overriding".
10150 -- Special exception, do not complain about failure to override the
10151 -- stream routines _Input and _Output, as well as the primitive
10152 -- operations used in dispatching selects since we always provide
10153 -- automatic overridings for these subprograms.
10155 -- The partial view of T may have been a private extension, for
10156 -- which inherited functions dispatching on result are abstract.
10157 -- If the full view is a null extension, there is no need for
10158 -- overriding in Ada 2005, but wrappers need to be built for them
10159 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
10161 if Is_Null_Extension (T)
10162 and then Has_Controlling_Result (Subp)
10163 and then Ada_Version >= Ada_2005
10164 and then Present (Alias_Subp)
10165 and then not Comes_From_Source (Subp)
10166 and then not Is_Abstract_Subprogram (Alias_Subp)
10167 and then not Is_Access_Type (Etype (Subp))
10171 -- Ada 2005 (AI-251): Internal entities of interfaces need no
10172 -- processing because this check is done with the aliased
10175 elsif Present (Interface_Alias (Subp)) then
10178 elsif (Is_Abstract_Subprogram (Subp)
10179 or else Requires_Overriding (Subp)
10181 (Has_Controlling_Result (Subp)
10182 and then Present (Alias_Subp)
10183 and then not Comes_From_Source (Subp)
10184 and then Sloc (Subp) = Sloc (First_Subtype (T))))
10185 and then not Is_TSS (Subp, TSS_Stream_Input)
10186 and then not Is_TSS (Subp, TSS_Stream_Output)
10187 and then not Is_Abstract_Type (T)
10188 and then not Is_Predefined_Interface_Primitive (Subp)
10190 -- Ada 2005 (AI-251): Do not consider hidden entities associated
10191 -- with abstract interface types because the check will be done
10192 -- with the aliased entity (otherwise we generate a duplicated
10195 and then not Present (Interface_Alias (Subp))
10197 if Present (Alias_Subp) then
10199 -- Only perform the check for a derived subprogram when the
10200 -- type has an explicit record extension. This avoids incorrect
10201 -- flagging of abstract subprograms for the case of a type
10202 -- without an extension that is derived from a formal type
10203 -- with a tagged actual (can occur within a private part).
10205 -- Ada 2005 (AI-391): In the case of an inherited function with
10206 -- a controlling result of the type, the rule does not apply if
10207 -- the type is a null extension (unless the parent function
10208 -- itself is abstract, in which case the function must still be
10209 -- be overridden). The expander will generate an overriding
10210 -- wrapper function calling the parent subprogram (see
10211 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
10213 Type_Def := Type_Definition (Parent (T));
10215 if Nkind (Type_Def) = N_Derived_Type_Definition
10216 and then Present (Record_Extension_Part (Type_Def))
10218 (Ada_Version < Ada_2005
10219 or else not Is_Null_Extension (T)
10220 or else Ekind (Subp) = E_Procedure
10221 or else not Has_Controlling_Result (Subp)
10222 or else Is_Abstract_Subprogram (Alias_Subp)
10223 or else Requires_Overriding (Subp)
10224 or else Is_Access_Type (Etype (Subp)))
10226 -- Avoid reporting error in case of abstract predefined
10227 -- primitive inherited from interface type because the
10228 -- body of internally generated predefined primitives
10229 -- of tagged types are generated later by Freeze_Type
10231 if Is_Interface (Root_Type (T))
10232 and then Is_Abstract_Subprogram (Subp)
10233 and then Is_Predefined_Dispatching_Operation (Subp)
10234 and then not Comes_From_Source (Ultimate_Alias (Subp))
10238 -- A null extension is not obliged to override an inherited
10239 -- procedure subject to pragma Extensions_Visible with value
10240 -- False and at least one controlling OUT parameter
10241 -- (SPARK RM 6.1.7(6)).
10243 elsif Is_Null_Extension (T)
10244 and then Is_EVF_Procedure (Subp)
10250 ("type must be declared abstract or & overridden",
10253 -- Traverse the whole chain of aliased subprograms to
10254 -- complete the error notification. This is especially
10255 -- useful for traceability of the chain of entities when
10256 -- the subprogram corresponds with an interface
10257 -- subprogram (which may be defined in another package).
10259 if Present (Alias_Subp) then
10265 while Present (Alias (E)) loop
10267 -- Avoid reporting redundant errors on entities
10268 -- inherited from interfaces
10270 if Sloc (E) /= Sloc (T) then
10271 Error_Msg_Sloc := Sloc (E);
10273 ("\& has been inherited #", T, Subp);
10279 Error_Msg_Sloc := Sloc (E);
10281 -- AI05-0068: report if there is an overriding
10282 -- non-abstract subprogram that is invisible.
10285 and then not Is_Abstract_Subprogram (E)
10288 ("\& subprogram# is not visible",
10291 -- Clarify the case where a non-null extension must
10292 -- override inherited procedure subject to pragma
10293 -- Extensions_Visible with value False and at least
10294 -- one controlling OUT param.
10296 elsif Is_EVF_Procedure (E) then
10298 ("\& # is subject to Extensions_Visible False",
10303 ("\& has been inherited from subprogram #",
10310 -- Ada 2005 (AI-345): Protected or task type implementing
10311 -- abstract interfaces.
10313 elsif Is_Concurrent_Record_Type (T)
10314 and then Present (Interfaces (T))
10316 -- There is no need to check here RM 9.4(11.9/3) since we
10317 -- are processing the corresponding record type and the
10318 -- mode of the overriding subprograms was verified by
10319 -- Check_Conformance when the corresponding concurrent
10320 -- type declaration was analyzed.
10323 ("interface subprogram & must be overridden", T, Subp);
10325 -- Examine primitive operations of synchronized type to find
10326 -- homonyms that have the wrong profile.
10332 Prim := First_Entity (Corresponding_Concurrent_Type (T));
10333 while Present (Prim) loop
10334 if Chars (Prim) = Chars (Subp) then
10336 ("profile is not type conformant with prefixed "
10337 & "view profile of inherited operation&",
10341 Next_Entity (Prim);
10347 Error_Msg_Node_2 := T;
10349 ("abstract subprogram& not allowed for type&", Subp);
10351 -- Also post unconditional warning on the type (unconditional
10352 -- so that if there are more than one of these cases, we get
10353 -- them all, and not just the first one).
10355 Error_Msg_Node_2 := Subp;
10356 Error_Msg_N ("nonabstract type& has abstract subprogram&!", T);
10359 -- A subprogram subject to pragma Extensions_Visible with value
10360 -- "True" cannot override a subprogram subject to the same pragma
10361 -- with value "False" (SPARK RM 6.1.7(5)).
10363 elsif Extensions_Visible_Status (Subp) = Extensions_Visible_True
10364 and then Present (Overridden_Operation (Subp))
10365 and then Extensions_Visible_Status (Overridden_Operation (Subp)) =
10366 Extensions_Visible_False
10368 Error_Msg_Sloc := Sloc (Overridden_Operation (Subp));
10370 ("subprogram & with Extensions_Visible True cannot override "
10371 & "subprogram # with Extensions_Visible False", Subp);
10374 -- Ada 2012 (AI05-0030): Perform checks related to pragma Implemented
10376 -- Subp is an expander-generated procedure which maps an interface
10377 -- alias to a protected wrapper. The interface alias is flagged by
10378 -- pragma Implemented. Ensure that Subp is a procedure when the
10379 -- implementation kind is By_Protected_Procedure or an entry when
10382 if Ada_Version >= Ada_2012
10383 and then Is_Hidden (Subp)
10384 and then Present (Interface_Alias (Subp))
10385 and then Has_Rep_Pragma (Interface_Alias (Subp), Name_Implemented)
10387 Check_Pragma_Implemented (Subp);
10390 -- Subp is an interface primitive which overrides another interface
10391 -- primitive marked with pragma Implemented.
10393 if Ada_Version >= Ada_2012
10394 and then Present (Overridden_Operation (Subp))
10395 and then Has_Rep_Pragma
10396 (Overridden_Operation (Subp), Name_Implemented)
10398 -- If the overriding routine is also marked by Implemented, check
10399 -- that the two implementation kinds are conforming.
10401 if Has_Rep_Pragma (Subp, Name_Implemented) then
10402 Check_Pragma_Implemented
10404 Iface_Subp => Overridden_Operation (Subp));
10406 -- Otherwise the overriding routine inherits the implementation
10407 -- kind from the overridden subprogram.
10410 Inherit_Pragma_Implemented
10412 Iface_Subp => Overridden_Operation (Subp));
10416 -- If the operation is a wrapper for a synchronized primitive, it
10417 -- may be called indirectly through a dispatching select. We assume
10418 -- that it will be referenced elsewhere indirectly, and suppress
10419 -- warnings about an unused entity.
10421 if Is_Primitive_Wrapper (Subp)
10422 and then Present (Wrapped_Entity (Subp))
10424 Set_Referenced (Wrapped_Entity (Subp));
10429 end Check_Abstract_Overriding;
10431 ------------------------------------------------
10432 -- Check_Access_Discriminant_Requires_Limited --
10433 ------------------------------------------------
10435 procedure Check_Access_Discriminant_Requires_Limited
10440 -- A discriminant_specification for an access discriminant shall appear
10441 -- only in the declaration for a task or protected type, or for a type
10442 -- with the reserved word 'limited' in its definition or in one of its
10443 -- ancestors (RM 3.7(10)).
10445 -- AI-0063: The proper condition is that type must be immutably limited,
10446 -- or else be a partial view.
10448 if Nkind (Discriminant_Type (D)) = N_Access_Definition then
10449 if Is_Limited_View (Current_Scope)
10451 (Nkind (Parent (Current_Scope)) = N_Private_Type_Declaration
10452 and then Limited_Present (Parent (Current_Scope)))
10458 ("access discriminants allowed only for limited types", Loc);
10461 end Check_Access_Discriminant_Requires_Limited;
10463 -----------------------------------
10464 -- Check_Aliased_Component_Types --
10465 -----------------------------------
10467 procedure Check_Aliased_Component_Types (T : Entity_Id) is
10471 -- ??? Also need to check components of record extensions, but not
10472 -- components of protected types (which are always limited).
10474 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
10475 -- types to be unconstrained. This is safe because it is illegal to
10476 -- create access subtypes to such types with explicit discriminant
10479 if not Is_Limited_Type (T) then
10480 if Ekind (T) = E_Record_Type then
10481 C := First_Component (T);
10482 while Present (C) loop
10484 and then Has_Discriminants (Etype (C))
10485 and then not Is_Constrained (Etype (C))
10486 and then not In_Instance_Body
10487 and then Ada_Version < Ada_2005
10490 ("aliased component must be constrained (RM 3.6(11))",
10494 Next_Component (C);
10497 elsif Ekind (T) = E_Array_Type then
10498 if Has_Aliased_Components (T)
10499 and then Has_Discriminants (Component_Type (T))
10500 and then not Is_Constrained (Component_Type (T))
10501 and then not In_Instance_Body
10502 and then Ada_Version < Ada_2005
10505 ("aliased component type must be constrained (RM 3.6(11))",
10510 end Check_Aliased_Component_Types;
10512 ---------------------------------------
10513 -- Check_Anonymous_Access_Components --
10514 ---------------------------------------
10516 procedure Check_Anonymous_Access_Components
10517 (Typ_Decl : Node_Id;
10520 Comp_List : Node_Id)
10522 Loc : constant Source_Ptr := Sloc (Typ_Decl);
10523 Anon_Access : Entity_Id;
10526 Comp_Def : Node_Id;
10528 Type_Def : Node_Id;
10530 procedure Build_Incomplete_Type_Declaration;
10531 -- If the record type contains components that include an access to the
10532 -- current record, then create an incomplete type declaration for the
10533 -- record, to be used as the designated type of the anonymous access.
10534 -- This is done only once, and only if there is no previous partial
10535 -- view of the type.
10537 function Designates_T (Subt : Node_Id) return Boolean;
10538 -- Check whether a node designates the enclosing record type, or 'Class
10541 function Mentions_T (Acc_Def : Node_Id) return Boolean;
10542 -- Check whether an access definition includes a reference to
10543 -- the enclosing record type. The reference can be a subtype mark
10544 -- in the access definition itself, a 'Class attribute reference, or
10545 -- recursively a reference appearing in a parameter specification
10546 -- or result definition of an access_to_subprogram definition.
10548 --------------------------------------
10549 -- Build_Incomplete_Type_Declaration --
10550 --------------------------------------
10552 procedure Build_Incomplete_Type_Declaration is
10557 -- Is_Tagged indicates whether the type is tagged. It is tagged if
10558 -- it's "is new ... with record" or else "is tagged record ...".
10560 Is_Tagged : constant Boolean :=
10561 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
10563 Present (Record_Extension_Part (Type_Definition (Typ_Decl))))
10565 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
10566 and then Tagged_Present (Type_Definition (Typ_Decl)));
10569 -- If there is a previous partial view, no need to create a new one
10570 -- If the partial view, given by Prev, is incomplete, If Prev is
10571 -- a private declaration, full declaration is flagged accordingly.
10573 if Prev /= Typ then
10575 Make_Class_Wide_Type (Prev);
10576 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
10577 Set_Etype (Class_Wide_Type (Typ), Typ);
10582 elsif Has_Private_Declaration (Typ) then
10584 -- If we refer to T'Class inside T, and T is the completion of a
10585 -- private type, then make sure the class-wide type exists.
10588 Make_Class_Wide_Type (Typ);
10593 -- If there was a previous anonymous access type, the incomplete
10594 -- type declaration will have been created already.
10596 elsif Present (Current_Entity (Typ))
10597 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
10598 and then Full_View (Current_Entity (Typ)) = Typ
10601 and then Comes_From_Source (Current_Entity (Typ))
10602 and then not Is_Tagged_Type (Current_Entity (Typ))
10604 Make_Class_Wide_Type (Typ);
10606 ("incomplete view of tagged type should be declared tagged??",
10607 Parent (Current_Entity (Typ)));
10612 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
10613 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
10615 -- Type has already been inserted into the current scope. Remove
10616 -- it, and add incomplete declaration for type, so that subsequent
10617 -- anonymous access types can use it. The entity is unchained from
10618 -- the homonym list and from immediate visibility. After analysis,
10619 -- the entity in the incomplete declaration becomes immediately
10620 -- visible in the record declaration that follows.
10622 H := Current_Entity (Typ);
10625 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
10628 and then Homonym (H) /= Typ
10630 H := Homonym (Typ);
10633 Set_Homonym (H, Homonym (Typ));
10636 Insert_Before (Typ_Decl, Decl);
10638 Set_Full_View (Inc_T, Typ);
10642 -- Create a common class-wide type for both views, and set the
10643 -- Etype of the class-wide type to the full view.
10645 Make_Class_Wide_Type (Inc_T);
10646 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
10647 Set_Etype (Class_Wide_Type (Typ), Typ);
10650 end Build_Incomplete_Type_Declaration;
10656 function Designates_T (Subt : Node_Id) return Boolean is
10657 Type_Id : constant Name_Id := Chars (Typ);
10659 function Names_T (Nam : Node_Id) return Boolean;
10660 -- The record type has not been introduced in the current scope
10661 -- yet, so we must examine the name of the type itself, either
10662 -- an identifier T, or an expanded name of the form P.T, where
10663 -- P denotes the current scope.
10669 function Names_T (Nam : Node_Id) return Boolean is
10671 if Nkind (Nam) = N_Identifier then
10672 return Chars (Nam) = Type_Id;
10674 elsif Nkind (Nam) = N_Selected_Component then
10675 if Chars (Selector_Name (Nam)) = Type_Id then
10676 if Nkind (Prefix (Nam)) = N_Identifier then
10677 return Chars (Prefix (Nam)) = Chars (Current_Scope);
10679 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
10680 return Chars (Selector_Name (Prefix (Nam))) =
10681 Chars (Current_Scope);
10695 -- Start of processing for Designates_T
10698 if Nkind (Subt) = N_Identifier then
10699 return Chars (Subt) = Type_Id;
10701 -- Reference can be through an expanded name which has not been
10702 -- analyzed yet, and which designates enclosing scopes.
10704 elsif Nkind (Subt) = N_Selected_Component then
10705 if Names_T (Subt) then
10708 -- Otherwise it must denote an entity that is already visible.
10709 -- The access definition may name a subtype of the enclosing
10710 -- type, if there is a previous incomplete declaration for it.
10713 Find_Selected_Component (Subt);
10715 Is_Entity_Name (Subt)
10716 and then Scope (Entity (Subt)) = Current_Scope
10718 (Chars (Base_Type (Entity (Subt))) = Type_Id
10720 (Is_Class_Wide_Type (Entity (Subt))
10722 Chars (Etype (Base_Type (Entity (Subt)))) =
10726 -- A reference to the current type may appear as the prefix of
10727 -- a 'Class attribute.
10729 elsif Nkind (Subt) = N_Attribute_Reference
10730 and then Attribute_Name (Subt) = Name_Class
10732 return Names_T (Prefix (Subt));
10743 function Mentions_T (Acc_Def : Node_Id) return Boolean is
10744 Param_Spec : Node_Id;
10746 Acc_Subprg : constant Node_Id :=
10747 Access_To_Subprogram_Definition (Acc_Def);
10750 if No (Acc_Subprg) then
10751 return Designates_T (Subtype_Mark (Acc_Def));
10754 -- Component is an access_to_subprogram: examine its formals,
10755 -- and result definition in the case of an access_to_function.
10757 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
10758 while Present (Param_Spec) loop
10759 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
10760 and then Mentions_T (Parameter_Type (Param_Spec))
10764 elsif Designates_T (Parameter_Type (Param_Spec)) then
10771 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
10772 if Nkind (Result_Definition (Acc_Subprg)) =
10773 N_Access_Definition
10775 return Mentions_T (Result_Definition (Acc_Subprg));
10777 return Designates_T (Result_Definition (Acc_Subprg));
10784 -- Start of processing for Check_Anonymous_Access_Components
10787 if No (Comp_List) then
10791 Comp := First (Component_Items (Comp_List));
10792 while Present (Comp) loop
10793 if Nkind (Comp) = N_Component_Declaration
10795 (Access_Definition (Component_Definition (Comp)))
10797 Mentions_T (Access_Definition (Component_Definition (Comp)))
10799 Comp_Def := Component_Definition (Comp);
10801 Access_To_Subprogram_Definition (Access_Definition (Comp_Def));
10803 Build_Incomplete_Type_Declaration;
10804 Anon_Access := Make_Temporary (Loc, 'S');
10806 -- Create a declaration for the anonymous access type: either
10807 -- an access_to_object or an access_to_subprogram.
10809 if Present (Acc_Def) then
10810 if Nkind (Acc_Def) = N_Access_Function_Definition then
10812 Make_Access_Function_Definition (Loc,
10813 Parameter_Specifications =>
10814 Parameter_Specifications (Acc_Def),
10815 Result_Definition => Result_Definition (Acc_Def));
10818 Make_Access_Procedure_Definition (Loc,
10819 Parameter_Specifications =>
10820 Parameter_Specifications (Acc_Def));
10825 Make_Access_To_Object_Definition (Loc,
10826 Subtype_Indication =>
10828 (Subtype_Mark (Access_Definition (Comp_Def))));
10830 Set_Constant_Present
10831 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
10833 (Type_Def, All_Present (Access_Definition (Comp_Def)));
10836 Set_Null_Exclusion_Present
10838 Null_Exclusion_Present (Access_Definition (Comp_Def)));
10841 Make_Full_Type_Declaration (Loc,
10842 Defining_Identifier => Anon_Access,
10843 Type_Definition => Type_Def);
10845 Insert_Before (Typ_Decl, Decl);
10848 -- If an access to subprogram, create the extra formals
10850 if Present (Acc_Def) then
10851 Create_Extra_Formals (Designated_Type (Anon_Access));
10853 -- If an access to object, preserve entity of designated type,
10854 -- for ASIS use, before rewriting the component definition.
10861 Desig := Entity (Subtype_Indication (Type_Def));
10863 -- If the access definition is to the current record,
10864 -- the visible entity at this point is an incomplete
10865 -- type. Retrieve the full view to simplify ASIS queries
10867 if Ekind (Desig) = E_Incomplete_Type then
10868 Desig := Full_View (Desig);
10872 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
10877 Make_Component_Definition (Loc,
10878 Subtype_Indication =>
10879 New_Occurrence_Of (Anon_Access, Loc)));
10881 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
10882 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
10884 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
10887 Set_Is_Local_Anonymous_Access (Anon_Access);
10893 if Present (Variant_Part (Comp_List)) then
10897 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
10898 while Present (V) loop
10899 Check_Anonymous_Access_Components
10900 (Typ_Decl, Typ, Prev, Component_List (V));
10901 Next_Non_Pragma (V);
10905 end Check_Anonymous_Access_Components;
10907 ----------------------
10908 -- Check_Completion --
10909 ----------------------
10911 procedure Check_Completion (Body_Id : Node_Id := Empty) is
10914 procedure Post_Error;
10915 -- Post error message for lack of completion for entity E
10921 procedure Post_Error is
10922 procedure Missing_Body;
10923 -- Output missing body message
10929 procedure Missing_Body is
10931 -- Spec is in same unit, so we can post on spec
10933 if In_Same_Source_Unit (Body_Id, E) then
10934 Error_Msg_N ("missing body for &", E);
10936 -- Spec is in a separate unit, so we have to post on the body
10939 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
10943 -- Start of processing for Post_Error
10946 if not Comes_From_Source (E) then
10947 if Ekind_In (E, E_Task_Type, E_Protected_Type) then
10949 -- It may be an anonymous protected type created for a
10950 -- single variable. Post error on variable, if present.
10956 Var := First_Entity (Current_Scope);
10957 while Present (Var) loop
10958 exit when Etype (Var) = E
10959 and then Comes_From_Source (Var);
10964 if Present (Var) then
10971 -- If a generated entity has no completion, then either previous
10972 -- semantic errors have disabled the expansion phase, or else we had
10973 -- missing subunits, or else we are compiling without expansion,
10974 -- or else something is very wrong.
10976 if not Comes_From_Source (E) then
10978 (Serious_Errors_Detected > 0
10979 or else Configurable_Run_Time_Violations > 0
10980 or else Subunits_Missing
10981 or else not Expander_Active);
10984 -- Here for source entity
10987 -- Here if no body to post the error message, so we post the error
10988 -- on the declaration that has no completion. This is not really
10989 -- the right place to post it, think about this later ???
10991 if No (Body_Id) then
10992 if Is_Type (E) then
10994 ("missing full declaration for }", Parent (E), E);
10996 Error_Msg_NE ("missing body for &", Parent (E), E);
10999 -- Package body has no completion for a declaration that appears
11000 -- in the corresponding spec. Post error on the body, with a
11001 -- reference to the non-completed declaration.
11004 Error_Msg_Sloc := Sloc (E);
11006 if Is_Type (E) then
11007 Error_Msg_NE ("missing full declaration for }!", Body_Id, E);
11009 elsif Is_Overloadable (E)
11010 and then Current_Entity_In_Scope (E) /= E
11012 -- It may be that the completion is mistyped and appears as
11013 -- a distinct overloading of the entity.
11016 Candidate : constant Entity_Id :=
11017 Current_Entity_In_Scope (E);
11018 Decl : constant Node_Id :=
11019 Unit_Declaration_Node (Candidate);
11022 if Is_Overloadable (Candidate)
11023 and then Ekind (Candidate) = Ekind (E)
11024 and then Nkind (Decl) = N_Subprogram_Body
11025 and then Acts_As_Spec (Decl)
11027 Check_Type_Conformant (Candidate, E);
11043 Pack_Id : constant Entity_Id := Current_Scope;
11045 -- Start of processing for Check_Completion
11048 E := First_Entity (Pack_Id);
11049 while Present (E) loop
11050 if Is_Intrinsic_Subprogram (E) then
11053 -- The following situation requires special handling: a child unit
11054 -- that appears in the context clause of the body of its parent:
11056 -- procedure Parent.Child (...);
11058 -- with Parent.Child;
11059 -- package body Parent is
11061 -- Here Parent.Child appears as a local entity, but should not be
11062 -- flagged as requiring completion, because it is a compilation
11065 -- Ignore missing completion for a subprogram that does not come from
11066 -- source (including the _Call primitive operation of RAS types,
11067 -- which has to have the flag Comes_From_Source for other purposes):
11068 -- we assume that the expander will provide the missing completion.
11069 -- In case of previous errors, other expansion actions that provide
11070 -- bodies for null procedures with not be invoked, so inhibit message
11073 -- Note that E_Operator is not in the list that follows, because
11074 -- this kind is reserved for predefined operators, that are
11075 -- intrinsic and do not need completion.
11077 elsif Ekind_In (E, E_Function,
11079 E_Generic_Function,
11080 E_Generic_Procedure)
11082 if Has_Completion (E) then
11085 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
11088 elsif Is_Subprogram (E)
11089 and then (not Comes_From_Source (E)
11090 or else Chars (E) = Name_uCall)
11095 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
11099 elsif Nkind (Parent (E)) = N_Procedure_Specification
11100 and then Null_Present (Parent (E))
11101 and then Serious_Errors_Detected > 0
11109 elsif Is_Entry (E) then
11110 if not Has_Completion (E) and then
11111 (Ekind (Scope (E)) = E_Protected_Object
11112 or else Ekind (Scope (E)) = E_Protected_Type)
11117 elsif Is_Package_Or_Generic_Package (E) then
11118 if Unit_Requires_Body (E) then
11119 if not Has_Completion (E)
11120 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
11126 elsif not Is_Child_Unit (E) then
11127 May_Need_Implicit_Body (E);
11130 -- A formal incomplete type (Ada 2012) does not require a completion;
11131 -- other incomplete type declarations do.
11133 elsif Ekind (E) = E_Incomplete_Type
11134 and then No (Underlying_Type (E))
11135 and then not Is_Generic_Type (E)
11139 elsif Ekind_In (E, E_Task_Type, E_Protected_Type)
11140 and then not Has_Completion (E)
11144 -- A single task declared in the current scope is a constant, verify
11145 -- that the body of its anonymous type is in the same scope. If the
11146 -- task is defined elsewhere, this may be a renaming declaration for
11147 -- which no completion is needed.
11149 elsif Ekind (E) = E_Constant
11150 and then Ekind (Etype (E)) = E_Task_Type
11151 and then not Has_Completion (Etype (E))
11152 and then Scope (Etype (E)) = Current_Scope
11156 elsif Ekind (E) = E_Protected_Object
11157 and then not Has_Completion (Etype (E))
11161 elsif Ekind (E) = E_Record_Type then
11162 if Is_Tagged_Type (E) then
11163 Check_Abstract_Overriding (E);
11164 Check_Conventions (E);
11167 Check_Aliased_Component_Types (E);
11169 elsif Ekind (E) = E_Array_Type then
11170 Check_Aliased_Component_Types (E);
11176 end Check_Completion;
11178 ------------------------------------
11179 -- Check_CPP_Type_Has_No_Defaults --
11180 ------------------------------------
11182 procedure Check_CPP_Type_Has_No_Defaults (T : Entity_Id) is
11183 Tdef : constant Node_Id := Type_Definition (Declaration_Node (T));
11188 -- Obtain the component list
11190 if Nkind (Tdef) = N_Record_Definition then
11191 Clist := Component_List (Tdef);
11192 else pragma Assert (Nkind (Tdef) = N_Derived_Type_Definition);
11193 Clist := Component_List (Record_Extension_Part (Tdef));
11196 -- Check all components to ensure no default expressions
11198 if Present (Clist) then
11199 Comp := First (Component_Items (Clist));
11200 while Present (Comp) loop
11201 if Present (Expression (Comp)) then
11203 ("component of imported 'C'P'P type cannot have "
11204 & "default expression", Expression (Comp));
11210 end Check_CPP_Type_Has_No_Defaults;
11212 ----------------------------
11213 -- Check_Delta_Expression --
11214 ----------------------------
11216 procedure Check_Delta_Expression (E : Node_Id) is
11218 if not (Is_Real_Type (Etype (E))) then
11219 Wrong_Type (E, Any_Real);
11221 elsif not Is_OK_Static_Expression (E) then
11222 Flag_Non_Static_Expr
11223 ("non-static expression used for delta value!", E);
11225 elsif not UR_Is_Positive (Expr_Value_R (E)) then
11226 Error_Msg_N ("delta expression must be positive", E);
11232 -- If any of above errors occurred, then replace the incorrect
11233 -- expression by the real 0.1, which should prevent further errors.
11236 Make_Real_Literal (Sloc (E), Ureal_Tenth));
11237 Analyze_And_Resolve (E, Standard_Float);
11238 end Check_Delta_Expression;
11240 -----------------------------
11241 -- Check_Digits_Expression --
11242 -----------------------------
11244 procedure Check_Digits_Expression (E : Node_Id) is
11246 if not (Is_Integer_Type (Etype (E))) then
11247 Wrong_Type (E, Any_Integer);
11249 elsif not Is_OK_Static_Expression (E) then
11250 Flag_Non_Static_Expr
11251 ("non-static expression used for digits value!", E);
11253 elsif Expr_Value (E) <= 0 then
11254 Error_Msg_N ("digits value must be greater than zero", E);
11260 -- If any of above errors occurred, then replace the incorrect
11261 -- expression by the integer 1, which should prevent further errors.
11263 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
11264 Analyze_And_Resolve (E, Standard_Integer);
11266 end Check_Digits_Expression;
11268 --------------------------
11269 -- Check_Initialization --
11270 --------------------------
11272 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
11274 -- Special processing for limited types
11276 if Is_Limited_Type (T)
11277 and then not In_Instance
11278 and then not In_Inlined_Body
11280 if not OK_For_Limited_Init (T, Exp) then
11282 -- In GNAT mode, this is just a warning, to allow it to be evilly
11283 -- turned off. Otherwise it is a real error.
11287 ("??cannot initialize entities of limited type!", Exp);
11289 elsif Ada_Version < Ada_2005 then
11291 -- The side effect removal machinery may generate illegal Ada
11292 -- code to avoid the usage of access types and 'reference in
11293 -- SPARK mode. Since this is legal code with respect to theorem
11294 -- proving, do not emit the error.
11297 and then Nkind (Exp) = N_Function_Call
11298 and then Nkind (Parent (Exp)) = N_Object_Declaration
11299 and then not Comes_From_Source
11300 (Defining_Identifier (Parent (Exp)))
11306 ("cannot initialize entities of limited type", Exp);
11307 Explain_Limited_Type (T, Exp);
11311 -- Specialize error message according to kind of illegal
11312 -- initial expression.
11314 if Nkind (Exp) = N_Type_Conversion
11315 and then Nkind (Expression (Exp)) = N_Function_Call
11318 ("illegal context for call"
11319 & " to function with limited result", Exp);
11323 ("initialization of limited object requires aggregate "
11324 & "or function call", Exp);
11330 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag gets
11331 -- set unless we can be sure that no range check is required.
11333 if (GNATprove_Mode or not Expander_Active)
11334 and then Is_Scalar_Type (T)
11335 and then not Is_In_Range (Exp, T, Assume_Valid => True)
11337 Set_Do_Range_Check (Exp);
11339 end Check_Initialization;
11341 ----------------------
11342 -- Check_Interfaces --
11343 ----------------------
11345 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
11346 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
11349 Iface_Def : Node_Id;
11350 Iface_Typ : Entity_Id;
11351 Parent_Node : Node_Id;
11353 Is_Task : Boolean := False;
11354 -- Set True if parent type or any progenitor is a task interface
11356 Is_Protected : Boolean := False;
11357 -- Set True if parent type or any progenitor is a protected interface
11359 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
11360 -- Check that a progenitor is compatible with declaration. If an error
11361 -- message is output, it is posted on Error_Node.
11367 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
11368 Iface_Id : constant Entity_Id :=
11369 Defining_Identifier (Parent (Iface_Def));
11370 Type_Def : Node_Id;
11373 if Nkind (N) = N_Private_Extension_Declaration then
11376 Type_Def := Type_Definition (N);
11379 if Is_Task_Interface (Iface_Id) then
11382 elsif Is_Protected_Interface (Iface_Id) then
11383 Is_Protected := True;
11386 if Is_Synchronized_Interface (Iface_Id) then
11388 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
11389 -- extension derived from a synchronized interface must explicitly
11390 -- be declared synchronized, because the full view will be a
11391 -- synchronized type.
11393 if Nkind (N) = N_Private_Extension_Declaration then
11394 if not Synchronized_Present (N) then
11396 ("private extension of& must be explicitly synchronized",
11400 -- However, by 3.9.4(16/2), a full type that is a record extension
11401 -- is never allowed to derive from a synchronized interface (note
11402 -- that interfaces must be excluded from this check, because those
11403 -- are represented by derived type definitions in some cases).
11405 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11406 and then not Interface_Present (Type_Definition (N))
11408 Error_Msg_N ("record extension cannot derive from synchronized "
11409 & "interface", Error_Node);
11413 -- Check that the characteristics of the progenitor are compatible
11414 -- with the explicit qualifier in the declaration.
11415 -- The check only applies to qualifiers that come from source.
11416 -- Limited_Present also appears in the declaration of corresponding
11417 -- records, and the check does not apply to them.
11419 if Limited_Present (Type_Def)
11421 Is_Concurrent_Record_Type (Defining_Identifier (N))
11423 if Is_Limited_Interface (Parent_Type)
11424 and then not Is_Limited_Interface (Iface_Id)
11427 ("progenitor & must be limited interface",
11428 Error_Node, Iface_Id);
11431 (Task_Present (Iface_Def)
11432 or else Protected_Present (Iface_Def)
11433 or else Synchronized_Present (Iface_Def))
11434 and then Nkind (N) /= N_Private_Extension_Declaration
11435 and then not Error_Posted (N)
11438 ("progenitor & must be limited interface",
11439 Error_Node, Iface_Id);
11442 -- Protected interfaces can only inherit from limited, synchronized
11443 -- or protected interfaces.
11445 elsif Nkind (N) = N_Full_Type_Declaration
11446 and then Protected_Present (Type_Def)
11448 if Limited_Present (Iface_Def)
11449 or else Synchronized_Present (Iface_Def)
11450 or else Protected_Present (Iface_Def)
11454 elsif Task_Present (Iface_Def) then
11455 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11456 & "from task interface", Error_Node);
11459 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11460 & "from non-limited interface", Error_Node);
11463 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
11464 -- limited and synchronized.
11466 elsif Synchronized_Present (Type_Def) then
11467 if Limited_Present (Iface_Def)
11468 or else Synchronized_Present (Iface_Def)
11472 elsif Protected_Present (Iface_Def)
11473 and then Nkind (N) /= N_Private_Extension_Declaration
11475 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11476 & "from protected interface", Error_Node);
11478 elsif Task_Present (Iface_Def)
11479 and then Nkind (N) /= N_Private_Extension_Declaration
11481 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11482 & "from task interface", Error_Node);
11484 elsif not Is_Limited_Interface (Iface_Id) then
11485 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11486 & "from non-limited interface", Error_Node);
11489 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
11490 -- synchronized or task interfaces.
11492 elsif Nkind (N) = N_Full_Type_Declaration
11493 and then Task_Present (Type_Def)
11495 if Limited_Present (Iface_Def)
11496 or else Synchronized_Present (Iface_Def)
11497 or else Task_Present (Iface_Def)
11501 elsif Protected_Present (Iface_Def) then
11502 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11503 & "protected interface", Error_Node);
11506 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11507 & "non-limited interface", Error_Node);
11512 -- Start of processing for Check_Interfaces
11515 if Is_Interface (Parent_Type) then
11516 if Is_Task_Interface (Parent_Type) then
11519 elsif Is_Protected_Interface (Parent_Type) then
11520 Is_Protected := True;
11524 if Nkind (N) = N_Private_Extension_Declaration then
11526 -- Check that progenitors are compatible with declaration
11528 Iface := First (Interface_List (Def));
11529 while Present (Iface) loop
11530 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11532 Parent_Node := Parent (Base_Type (Iface_Typ));
11533 Iface_Def := Type_Definition (Parent_Node);
11535 if not Is_Interface (Iface_Typ) then
11536 Diagnose_Interface (Iface, Iface_Typ);
11538 Check_Ifaces (Iface_Def, Iface);
11544 if Is_Task and Is_Protected then
11546 ("type cannot derive from task and protected interface", N);
11552 -- Full type declaration of derived type.
11553 -- Check compatibility with parent if it is interface type
11555 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11556 and then Is_Interface (Parent_Type)
11558 Parent_Node := Parent (Parent_Type);
11560 -- More detailed checks for interface varieties
11563 (Iface_Def => Type_Definition (Parent_Node),
11564 Error_Node => Subtype_Indication (Type_Definition (N)));
11567 Iface := First (Interface_List (Def));
11568 while Present (Iface) loop
11569 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11571 Parent_Node := Parent (Base_Type (Iface_Typ));
11572 Iface_Def := Type_Definition (Parent_Node);
11574 if not Is_Interface (Iface_Typ) then
11575 Diagnose_Interface (Iface, Iface_Typ);
11578 -- "The declaration of a specific descendant of an interface
11579 -- type freezes the interface type" RM 13.14
11581 Freeze_Before (N, Iface_Typ);
11582 Check_Ifaces (Iface_Def, Error_Node => Iface);
11588 if Is_Task and Is_Protected then
11590 ("type cannot derive from task and protected interface", N);
11592 end Check_Interfaces;
11594 ------------------------------------
11595 -- Check_Or_Process_Discriminants --
11596 ------------------------------------
11598 -- If an incomplete or private type declaration was already given for the
11599 -- type, the discriminants may have already been processed if they were
11600 -- present on the incomplete declaration. In this case a full conformance
11601 -- check has been performed in Find_Type_Name, and we then recheck here
11602 -- some properties that can't be checked on the partial view alone.
11603 -- Otherwise we call Process_Discriminants.
11605 procedure Check_Or_Process_Discriminants
11608 Prev : Entity_Id := Empty)
11611 if Has_Discriminants (T) then
11613 -- Discriminants are already set on T if they were already present
11614 -- on the partial view. Make them visible to component declarations.
11618 -- Discriminant on T (full view) referencing expr on partial view
11620 Prev_D : Entity_Id;
11621 -- Entity of corresponding discriminant on partial view
11624 -- Discriminant specification for full view, expression is
11625 -- the syntactic copy on full view (which has been checked for
11626 -- conformance with partial view), only used here to post error
11630 D := First_Discriminant (T);
11631 New_D := First (Discriminant_Specifications (N));
11632 while Present (D) loop
11633 Prev_D := Current_Entity (D);
11634 Set_Current_Entity (D);
11635 Set_Is_Immediately_Visible (D);
11636 Set_Homonym (D, Prev_D);
11638 -- Handle the case where there is an untagged partial view and
11639 -- the full view is tagged: must disallow discriminants with
11640 -- defaults, unless compiling for Ada 2012, which allows a
11641 -- limited tagged type to have defaulted discriminants (see
11642 -- AI05-0214). However, suppress error here if it was already
11643 -- reported on the default expression of the partial view.
11645 if Is_Tagged_Type (T)
11646 and then Present (Expression (Parent (D)))
11647 and then (not Is_Limited_Type (Current_Scope)
11648 or else Ada_Version < Ada_2012)
11649 and then not Error_Posted (Expression (Parent (D)))
11651 if Ada_Version >= Ada_2012 then
11653 ("discriminants of nonlimited tagged type cannot have "
11655 Expression (New_D));
11658 ("discriminants of tagged type cannot have defaults",
11659 Expression (New_D));
11663 -- Ada 2005 (AI-230): Access discriminant allowed in
11664 -- non-limited record types.
11666 if Ada_Version < Ada_2005 then
11668 -- This restriction gets applied to the full type here. It
11669 -- has already been applied earlier to the partial view.
11671 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
11674 Next_Discriminant (D);
11679 elsif Present (Discriminant_Specifications (N)) then
11680 Process_Discriminants (N, Prev);
11682 end Check_Or_Process_Discriminants;
11684 ----------------------
11685 -- Check_Real_Bound --
11686 ----------------------
11688 procedure Check_Real_Bound (Bound : Node_Id) is
11690 if not Is_Real_Type (Etype (Bound)) then
11692 ("bound in real type definition must be of real type", Bound);
11694 elsif not Is_OK_Static_Expression (Bound) then
11695 Flag_Non_Static_Expr
11696 ("non-static expression used for real type bound!", Bound);
11703 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
11705 Resolve (Bound, Standard_Float);
11706 end Check_Real_Bound;
11708 ------------------------------
11709 -- Complete_Private_Subtype --
11710 ------------------------------
11712 procedure Complete_Private_Subtype
11715 Full_Base : Entity_Id;
11716 Related_Nod : Node_Id)
11718 Save_Next_Entity : Entity_Id;
11719 Save_Homonym : Entity_Id;
11722 -- Set semantic attributes for (implicit) private subtype completion.
11723 -- If the full type has no discriminants, then it is a copy of the
11724 -- full view of the base. Otherwise, it is a subtype of the base with
11725 -- a possible discriminant constraint. Save and restore the original
11726 -- Next_Entity field of full to ensure that the calls to Copy_Node do
11727 -- not corrupt the entity chain.
11729 -- Note that the type of the full view is the same entity as the type
11730 -- of the partial view. In this fashion, the subtype has access to the
11731 -- correct view of the parent.
11733 Save_Next_Entity := Next_Entity (Full);
11734 Save_Homonym := Homonym (Priv);
11736 case Ekind (Full_Base) is
11737 when E_Record_Type |
11743 Copy_Node (Priv, Full);
11745 Set_Has_Discriminants
11746 (Full, Has_Discriminants (Full_Base));
11747 Set_Has_Unknown_Discriminants
11748 (Full, Has_Unknown_Discriminants (Full_Base));
11749 Set_First_Entity (Full, First_Entity (Full_Base));
11750 Set_Last_Entity (Full, Last_Entity (Full_Base));
11752 -- If the underlying base type is constrained, we know that the
11753 -- full view of the subtype is constrained as well (the converse
11754 -- is not necessarily true).
11756 if Is_Constrained (Full_Base) then
11757 Set_Is_Constrained (Full);
11761 Copy_Node (Full_Base, Full);
11763 Set_Chars (Full, Chars (Priv));
11764 Conditional_Delay (Full, Priv);
11765 Set_Sloc (Full, Sloc (Priv));
11768 Set_Next_Entity (Full, Save_Next_Entity);
11769 Set_Homonym (Full, Save_Homonym);
11770 Set_Associated_Node_For_Itype (Full, Related_Nod);
11772 -- Set common attributes for all subtypes: kind, convention, etc.
11774 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
11775 Set_Convention (Full, Convention (Full_Base));
11777 -- The Etype of the full view is inconsistent. Gigi needs to see the
11778 -- structural full view, which is what the current scheme gives: the
11779 -- Etype of the full view is the etype of the full base. However, if the
11780 -- full base is a derived type, the full view then looks like a subtype
11781 -- of the parent, not a subtype of the full base. If instead we write:
11783 -- Set_Etype (Full, Full_Base);
11785 -- then we get inconsistencies in the front-end (confusion between
11786 -- views). Several outstanding bugs are related to this ???
11788 Set_Is_First_Subtype (Full, False);
11789 Set_Scope (Full, Scope (Priv));
11790 Set_Size_Info (Full, Full_Base);
11791 Set_RM_Size (Full, RM_Size (Full_Base));
11792 Set_Is_Itype (Full);
11794 -- A subtype of a private-type-without-discriminants, whose full-view
11795 -- has discriminants with default expressions, is not constrained.
11797 if not Has_Discriminants (Priv) then
11798 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
11800 if Has_Discriminants (Full_Base) then
11801 Set_Discriminant_Constraint
11802 (Full, Discriminant_Constraint (Full_Base));
11804 -- The partial view may have been indefinite, the full view
11807 Set_Has_Unknown_Discriminants
11808 (Full, Has_Unknown_Discriminants (Full_Base));
11812 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
11813 Set_Depends_On_Private (Full, Has_Private_Component (Full));
11815 -- Freeze the private subtype entity if its parent is delayed, and not
11816 -- already frozen. We skip this processing if the type is an anonymous
11817 -- subtype of a record component, or is the corresponding record of a
11818 -- protected type, since these are processed when the enclosing type
11821 if not Is_Type (Scope (Full)) then
11822 Set_Has_Delayed_Freeze (Full,
11823 Has_Delayed_Freeze (Full_Base)
11824 and then (not Is_Frozen (Full_Base)));
11827 Set_Freeze_Node (Full, Empty);
11828 Set_Is_Frozen (Full, False);
11829 Set_Full_View (Priv, Full);
11831 if Has_Discriminants (Full) then
11832 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
11833 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
11835 if Has_Unknown_Discriminants (Full) then
11836 Set_Discriminant_Constraint (Full, No_Elist);
11840 if Ekind (Full_Base) = E_Record_Type
11841 and then Has_Discriminants (Full_Base)
11842 and then Has_Discriminants (Priv) -- might not, if errors
11843 and then not Has_Unknown_Discriminants (Priv)
11844 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
11846 Create_Constrained_Components
11847 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
11849 -- If the full base is itself derived from private, build a congruent
11850 -- subtype of its underlying type, for use by the back end. For a
11851 -- constrained record component, the declaration cannot be placed on
11852 -- the component list, but it must nevertheless be built an analyzed, to
11853 -- supply enough information for Gigi to compute the size of component.
11855 elsif Ekind (Full_Base) in Private_Kind
11856 and then Is_Derived_Type (Full_Base)
11857 and then Has_Discriminants (Full_Base)
11858 and then (Ekind (Current_Scope) /= E_Record_Subtype)
11860 if not Is_Itype (Priv)
11862 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
11864 Build_Underlying_Full_View
11865 (Parent (Priv), Full, Etype (Full_Base));
11867 elsif Nkind (Related_Nod) = N_Component_Declaration then
11868 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
11871 elsif Is_Record_Type (Full_Base) then
11873 -- Show Full is simply a renaming of Full_Base
11875 Set_Cloned_Subtype (Full, Full_Base);
11878 -- It is unsafe to share the bounds of a scalar type, because the Itype
11879 -- is elaborated on demand, and if a bound is non-static then different
11880 -- orders of elaboration in different units will lead to different
11881 -- external symbols.
11883 if Is_Scalar_Type (Full_Base) then
11884 Set_Scalar_Range (Full,
11885 Make_Range (Sloc (Related_Nod),
11887 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
11889 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
11891 -- This completion inherits the bounds of the full parent, but if
11892 -- the parent is an unconstrained floating point type, so is the
11895 if Is_Floating_Point_Type (Full_Base) then
11896 Set_Includes_Infinities
11897 (Scalar_Range (Full), Has_Infinities (Full_Base));
11901 -- ??? It seems that a lot of fields are missing that should be copied
11902 -- from Full_Base to Full. Here are some that are introduced in a
11903 -- non-disruptive way but a cleanup is necessary.
11905 if Is_Tagged_Type (Full_Base) then
11906 Set_Is_Tagged_Type (Full);
11907 Set_Direct_Primitive_Operations
11908 (Full, Direct_Primitive_Operations (Full_Base));
11909 Set_No_Tagged_Streams_Pragma
11910 (Full, No_Tagged_Streams_Pragma (Full_Base));
11912 -- Inherit class_wide type of full_base in case the partial view was
11913 -- not tagged. Otherwise it has already been created when the private
11914 -- subtype was analyzed.
11916 if No (Class_Wide_Type (Full)) then
11917 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
11920 -- If this is a subtype of a protected or task type, constrain its
11921 -- corresponding record, unless this is a subtype without constraints,
11922 -- i.e. a simple renaming as with an actual subtype in an instance.
11924 elsif Is_Concurrent_Type (Full_Base) then
11925 if Has_Discriminants (Full)
11926 and then Present (Corresponding_Record_Type (Full_Base))
11928 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
11930 Set_Corresponding_Record_Type (Full,
11931 Constrain_Corresponding_Record
11932 (Full, Corresponding_Record_Type (Full_Base), Related_Nod));
11935 Set_Corresponding_Record_Type (Full,
11936 Corresponding_Record_Type (Full_Base));
11940 -- Link rep item chain, and also setting of Has_Predicates from private
11941 -- subtype to full subtype, since we will need these on the full subtype
11942 -- to create the predicate function. Note that the full subtype may
11943 -- already have rep items, inherited from the full view of the base
11944 -- type, so we must be sure not to overwrite these entries.
11949 Next_Item : Node_Id;
11950 Priv_Item : Node_Id;
11953 Item := First_Rep_Item (Full);
11954 Priv_Item := First_Rep_Item (Priv);
11956 -- If no existing rep items on full type, we can just link directly
11957 -- to the list of items on the private type, if any exist.. Same if
11958 -- the rep items are only those inherited from the base
11961 or else Nkind (Item) /= N_Aspect_Specification
11962 or else Entity (Item) = Full_Base)
11963 and then Present (First_Rep_Item (Priv))
11965 Set_First_Rep_Item (Full, Priv_Item);
11967 -- Otherwise, search to the end of items currently linked to the full
11968 -- subtype and append the private items to the end. However, if Priv
11969 -- and Full already have the same list of rep items, then the append
11970 -- is not done, as that would create a circularity.
11972 -- The partial view may have a predicate and the rep item lists of
11973 -- both views agree when inherited from the same ancestor. In that
11974 -- case, simply propagate the list from one view to the other.
11975 -- A more complex analysis needed here ???
11977 elsif Present (Priv_Item)
11978 and then Item = Next_Rep_Item (Priv_Item)
11980 Set_First_Rep_Item (Full, Priv_Item);
11982 elsif Item /= Priv_Item then
11985 Next_Item := Next_Rep_Item (Item);
11986 exit when No (Next_Item);
11989 -- If the private view has aspect specifications, the full view
11990 -- inherits them. Since these aspects may already have been
11991 -- attached to the full view during derivation, do not append
11992 -- them if already present.
11994 if Item = First_Rep_Item (Priv) then
12000 -- And link the private type items at the end of the chain
12003 Set_Next_Rep_Item (Item, First_Rep_Item (Priv));
12008 -- Make sure Has_Predicates is set on full type if it is set on the
12009 -- private type. Note that it may already be set on the full type and
12010 -- if so, we don't want to unset it. Similarly, propagate information
12011 -- about delayed aspects, because the corresponding pragmas must be
12012 -- analyzed when one of the views is frozen. This last step is needed
12013 -- in particular when the full type is a scalar type for which an
12014 -- anonymous base type is constructed.
12016 -- The predicate functions are generated either at the freeze point
12017 -- of the type or at the end of the visible part, and we must avoid
12018 -- generating them twice.
12020 if Has_Predicates (Priv) then
12021 Set_Has_Predicates (Full);
12023 if Present (Predicate_Function (Priv))
12024 and then No (Predicate_Function (Full))
12026 Set_Predicate_Function (Full, Predicate_Function (Priv));
12030 if Has_Delayed_Aspects (Priv) then
12031 Set_Has_Delayed_Aspects (Full);
12033 end Complete_Private_Subtype;
12035 ----------------------------
12036 -- Constant_Redeclaration --
12037 ----------------------------
12039 procedure Constant_Redeclaration
12044 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
12045 Obj_Def : constant Node_Id := Object_Definition (N);
12048 procedure Check_Possible_Deferred_Completion
12049 (Prev_Id : Entity_Id;
12050 Prev_Obj_Def : Node_Id;
12051 Curr_Obj_Def : Node_Id);
12052 -- Determine whether the two object definitions describe the partial
12053 -- and the full view of a constrained deferred constant. Generate
12054 -- a subtype for the full view and verify that it statically matches
12055 -- the subtype of the partial view.
12057 procedure Check_Recursive_Declaration (Typ : Entity_Id);
12058 -- If deferred constant is an access type initialized with an allocator,
12059 -- check whether there is an illegal recursion in the definition,
12060 -- through a default value of some record subcomponent. This is normally
12061 -- detected when generating init procs, but requires this additional
12062 -- mechanism when expansion is disabled.
12064 ----------------------------------------
12065 -- Check_Possible_Deferred_Completion --
12066 ----------------------------------------
12068 procedure Check_Possible_Deferred_Completion
12069 (Prev_Id : Entity_Id;
12070 Prev_Obj_Def : Node_Id;
12071 Curr_Obj_Def : Node_Id)
12074 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
12075 and then Present (Constraint (Prev_Obj_Def))
12076 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
12077 and then Present (Constraint (Curr_Obj_Def))
12080 Loc : constant Source_Ptr := Sloc (N);
12081 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'S');
12082 Decl : constant Node_Id :=
12083 Make_Subtype_Declaration (Loc,
12084 Defining_Identifier => Def_Id,
12085 Subtype_Indication =>
12086 Relocate_Node (Curr_Obj_Def));
12089 Insert_Before_And_Analyze (N, Decl);
12090 Set_Etype (Id, Def_Id);
12092 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
12093 Error_Msg_Sloc := Sloc (Prev_Id);
12094 Error_Msg_N ("subtype does not statically match deferred "
12095 & "declaration #", N);
12099 end Check_Possible_Deferred_Completion;
12101 ---------------------------------
12102 -- Check_Recursive_Declaration --
12103 ---------------------------------
12105 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
12109 if Is_Record_Type (Typ) then
12110 Comp := First_Component (Typ);
12111 while Present (Comp) loop
12112 if Comes_From_Source (Comp) then
12113 if Present (Expression (Parent (Comp)))
12114 and then Is_Entity_Name (Expression (Parent (Comp)))
12115 and then Entity (Expression (Parent (Comp))) = Prev
12117 Error_Msg_Sloc := Sloc (Parent (Comp));
12119 ("illegal circularity with declaration for & #",
12123 elsif Is_Record_Type (Etype (Comp)) then
12124 Check_Recursive_Declaration (Etype (Comp));
12128 Next_Component (Comp);
12131 end Check_Recursive_Declaration;
12133 -- Start of processing for Constant_Redeclaration
12136 if Nkind (Parent (Prev)) = N_Object_Declaration then
12137 if Nkind (Object_Definition
12138 (Parent (Prev))) = N_Subtype_Indication
12140 -- Find type of new declaration. The constraints of the two
12141 -- views must match statically, but there is no point in
12142 -- creating an itype for the full view.
12144 if Nkind (Obj_Def) = N_Subtype_Indication then
12145 Find_Type (Subtype_Mark (Obj_Def));
12146 New_T := Entity (Subtype_Mark (Obj_Def));
12149 Find_Type (Obj_Def);
12150 New_T := Entity (Obj_Def);
12156 -- The full view may impose a constraint, even if the partial
12157 -- view does not, so construct the subtype.
12159 New_T := Find_Type_Of_Object (Obj_Def, N);
12164 -- Current declaration is illegal, diagnosed below in Enter_Name
12170 -- If previous full declaration or a renaming declaration exists, or if
12171 -- a homograph is present, let Enter_Name handle it, either with an
12172 -- error or with the removal of an overridden implicit subprogram.
12173 -- The previous one is a full declaration if it has an expression
12174 -- (which in the case of an aggregate is indicated by the Init flag).
12176 if Ekind (Prev) /= E_Constant
12177 or else Nkind (Parent (Prev)) = N_Object_Renaming_Declaration
12178 or else Present (Expression (Parent (Prev)))
12179 or else Has_Init_Expression (Parent (Prev))
12180 or else Present (Full_View (Prev))
12184 -- Verify that types of both declarations match, or else that both types
12185 -- are anonymous access types whose designated subtypes statically match
12186 -- (as allowed in Ada 2005 by AI-385).
12188 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
12190 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
12191 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
12192 or else Is_Access_Constant (Etype (New_T)) /=
12193 Is_Access_Constant (Etype (Prev))
12194 or else Can_Never_Be_Null (Etype (New_T)) /=
12195 Can_Never_Be_Null (Etype (Prev))
12196 or else Null_Exclusion_Present (Parent (Prev)) /=
12197 Null_Exclusion_Present (Parent (Id))
12198 or else not Subtypes_Statically_Match
12199 (Designated_Type (Etype (Prev)),
12200 Designated_Type (Etype (New_T))))
12202 Error_Msg_Sloc := Sloc (Prev);
12203 Error_Msg_N ("type does not match declaration#", N);
12204 Set_Full_View (Prev, Id);
12205 Set_Etype (Id, Any_Type);
12207 -- A deferred constant whose type is an anonymous array is always
12208 -- illegal (unless imported). A detailed error message might be
12209 -- helpful for Ada beginners.
12211 if Nkind (Object_Definition (Parent (Prev)))
12212 = N_Constrained_Array_Definition
12213 and then Nkind (Object_Definition (N))
12214 = N_Constrained_Array_Definition
12216 Error_Msg_N ("\each anonymous array is a distinct type", N);
12217 Error_Msg_N ("a deferred constant must have a named type",
12218 Object_Definition (Parent (Prev)));
12222 Null_Exclusion_Present (Parent (Prev))
12223 and then not Null_Exclusion_Present (N)
12225 Error_Msg_Sloc := Sloc (Prev);
12226 Error_Msg_N ("null-exclusion does not match declaration#", N);
12227 Set_Full_View (Prev, Id);
12228 Set_Etype (Id, Any_Type);
12230 -- If so, process the full constant declaration
12233 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
12234 -- the deferred declaration is constrained, then the subtype defined
12235 -- by the subtype_indication in the full declaration shall match it
12238 Check_Possible_Deferred_Completion
12240 Prev_Obj_Def => Object_Definition (Parent (Prev)),
12241 Curr_Obj_Def => Obj_Def);
12243 Set_Full_View (Prev, Id);
12244 Set_Is_Public (Id, Is_Public (Prev));
12245 Set_Is_Internal (Id);
12246 Append_Entity (Id, Current_Scope);
12248 -- Check ALIASED present if present before (RM 7.4(7))
12250 if Is_Aliased (Prev)
12251 and then not Aliased_Present (N)
12253 Error_Msg_Sloc := Sloc (Prev);
12254 Error_Msg_N ("ALIASED required (see declaration #)", N);
12257 -- Check that placement is in private part and that the incomplete
12258 -- declaration appeared in the visible part.
12260 if Ekind (Current_Scope) = E_Package
12261 and then not In_Private_Part (Current_Scope)
12263 Error_Msg_Sloc := Sloc (Prev);
12265 ("full constant for declaration # must be in private part", N);
12267 elsif Ekind (Current_Scope) = E_Package
12269 List_Containing (Parent (Prev)) /=
12270 Visible_Declarations (Package_Specification (Current_Scope))
12273 ("deferred constant must be declared in visible part",
12277 if Is_Access_Type (T)
12278 and then Nkind (Expression (N)) = N_Allocator
12280 Check_Recursive_Declaration (Designated_Type (T));
12283 -- A deferred constant is a visible entity. If type has invariants,
12284 -- verify that the initial value satisfies them.
12286 if Has_Invariants (T) and then Present (Invariant_Procedure (T)) then
12288 Make_Invariant_Call (New_Occurrence_Of (Prev, Sloc (N))));
12291 end Constant_Redeclaration;
12293 ----------------------
12294 -- Constrain_Access --
12295 ----------------------
12297 procedure Constrain_Access
12298 (Def_Id : in out Entity_Id;
12300 Related_Nod : Node_Id)
12302 T : constant Entity_Id := Entity (Subtype_Mark (S));
12303 Desig_Type : constant Entity_Id := Designated_Type (T);
12304 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
12305 Constraint_OK : Boolean := True;
12308 if Is_Array_Type (Desig_Type) then
12309 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
12311 elsif (Is_Record_Type (Desig_Type)
12312 or else Is_Incomplete_Or_Private_Type (Desig_Type))
12313 and then not Is_Constrained (Desig_Type)
12315 -- ??? The following code is a temporary bypass to ignore a
12316 -- discriminant constraint on access type if it is constraining
12317 -- the current record. Avoid creating the implicit subtype of the
12318 -- record we are currently compiling since right now, we cannot
12319 -- handle these. For now, just return the access type itself.
12321 if Desig_Type = Current_Scope
12322 and then No (Def_Id)
12324 Set_Ekind (Desig_Subtype, E_Record_Subtype);
12325 Def_Id := Entity (Subtype_Mark (S));
12327 -- This call added to ensure that the constraint is analyzed
12328 -- (needed for a B test). Note that we still return early from
12329 -- this procedure to avoid recursive processing. ???
12331 Constrain_Discriminated_Type
12332 (Desig_Subtype, S, Related_Nod, For_Access => True);
12336 -- Enforce rule that the constraint is illegal if there is an
12337 -- unconstrained view of the designated type. This means that the
12338 -- partial view (either a private type declaration or a derivation
12339 -- from a private type) has no discriminants. (Defect Report
12340 -- 8652/0008, Technical Corrigendum 1, checked by ACATS B371001).
12342 -- Rule updated for Ada 2005: The private type is said to have
12343 -- a constrained partial view, given that objects of the type
12344 -- can be declared. Furthermore, the rule applies to all access
12345 -- types, unlike the rule concerning default discriminants (see
12348 if (Ekind (T) = E_General_Access_Type or else Ada_Version >= Ada_2005)
12349 and then Has_Private_Declaration (Desig_Type)
12350 and then In_Open_Scopes (Scope (Desig_Type))
12351 and then Has_Discriminants (Desig_Type)
12354 Pack : constant Node_Id :=
12355 Unit_Declaration_Node (Scope (Desig_Type));
12360 if Nkind (Pack) = N_Package_Declaration then
12361 Decls := Visible_Declarations (Specification (Pack));
12362 Decl := First (Decls);
12363 while Present (Decl) loop
12364 if (Nkind (Decl) = N_Private_Type_Declaration
12365 and then Chars (Defining_Identifier (Decl)) =
12366 Chars (Desig_Type))
12369 (Nkind (Decl) = N_Full_Type_Declaration
12371 Chars (Defining_Identifier (Decl)) =
12373 and then Is_Derived_Type (Desig_Type)
12375 Has_Private_Declaration (Etype (Desig_Type)))
12377 if No (Discriminant_Specifications (Decl)) then
12379 ("cannot constrain access type if designated "
12380 & "type has constrained partial view", S);
12392 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
12393 For_Access => True);
12395 elsif Is_Concurrent_Type (Desig_Type)
12396 and then not Is_Constrained (Desig_Type)
12398 Constrain_Concurrent (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
12401 Error_Msg_N ("invalid constraint on access type", S);
12403 -- We simply ignore an invalid constraint
12405 Desig_Subtype := Desig_Type;
12406 Constraint_OK := False;
12409 if No (Def_Id) then
12410 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
12412 Set_Ekind (Def_Id, E_Access_Subtype);
12415 if Constraint_OK then
12416 Set_Etype (Def_Id, Base_Type (T));
12418 if Is_Private_Type (Desig_Type) then
12419 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
12422 Set_Etype (Def_Id, Any_Type);
12425 Set_Size_Info (Def_Id, T);
12426 Set_Is_Constrained (Def_Id, Constraint_OK);
12427 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
12428 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12429 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
12431 Conditional_Delay (Def_Id, T);
12433 -- AI-363 : Subtypes of general access types whose designated types have
12434 -- default discriminants are disallowed. In instances, the rule has to
12435 -- be checked against the actual, of which T is the subtype. In a
12436 -- generic body, the rule is checked assuming that the actual type has
12437 -- defaulted discriminants.
12439 if Ada_Version >= Ada_2005 or else Warn_On_Ada_2005_Compatibility then
12440 if Ekind (Base_Type (T)) = E_General_Access_Type
12441 and then Has_Defaulted_Discriminants (Desig_Type)
12443 if Ada_Version < Ada_2005 then
12445 ("access subtype of general access type would not " &
12446 "be allowed in Ada 2005?y?", S);
12449 ("access subtype of general access type not allowed", S);
12452 Error_Msg_N ("\discriminants have defaults", S);
12454 elsif Is_Access_Type (T)
12455 and then Is_Generic_Type (Desig_Type)
12456 and then Has_Discriminants (Desig_Type)
12457 and then In_Package_Body (Current_Scope)
12459 if Ada_Version < Ada_2005 then
12461 ("access subtype would not be allowed in generic body "
12462 & "in Ada 2005?y?", S);
12465 ("access subtype not allowed in generic body", S);
12469 ("\designated type is a discriminated formal", S);
12472 end Constrain_Access;
12474 ---------------------
12475 -- Constrain_Array --
12476 ---------------------
12478 procedure Constrain_Array
12479 (Def_Id : in out Entity_Id;
12481 Related_Nod : Node_Id;
12482 Related_Id : Entity_Id;
12483 Suffix : Character)
12485 C : constant Node_Id := Constraint (SI);
12486 Number_Of_Constraints : Nat := 0;
12489 Constraint_OK : Boolean := True;
12492 T := Entity (Subtype_Mark (SI));
12494 if Is_Access_Type (T) then
12495 T := Designated_Type (T);
12498 -- If an index constraint follows a subtype mark in a subtype indication
12499 -- then the type or subtype denoted by the subtype mark must not already
12500 -- impose an index constraint. The subtype mark must denote either an
12501 -- unconstrained array type or an access type whose designated type
12502 -- is such an array type... (RM 3.6.1)
12504 if Is_Constrained (T) then
12505 Error_Msg_N ("array type is already constrained", Subtype_Mark (SI));
12506 Constraint_OK := False;
12509 S := First (Constraints (C));
12510 while Present (S) loop
12511 Number_Of_Constraints := Number_Of_Constraints + 1;
12515 -- In either case, the index constraint must provide a discrete
12516 -- range for each index of the array type and the type of each
12517 -- discrete range must be the same as that of the corresponding
12518 -- index. (RM 3.6.1)
12520 if Number_Of_Constraints /= Number_Dimensions (T) then
12521 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
12522 Constraint_OK := False;
12525 S := First (Constraints (C));
12526 Index := First_Index (T);
12529 -- Apply constraints to each index type
12531 for J in 1 .. Number_Of_Constraints loop
12532 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
12540 if No (Def_Id) then
12542 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
12543 Set_Parent (Def_Id, Related_Nod);
12546 Set_Ekind (Def_Id, E_Array_Subtype);
12549 Set_Size_Info (Def_Id, (T));
12550 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12551 Set_Etype (Def_Id, Base_Type (T));
12553 if Constraint_OK then
12554 Set_First_Index (Def_Id, First (Constraints (C)));
12556 Set_First_Index (Def_Id, First_Index (T));
12559 Set_Is_Constrained (Def_Id, True);
12560 Set_Is_Aliased (Def_Id, Is_Aliased (T));
12561 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12563 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
12564 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
12566 -- A subtype does not inherit the Packed_Array_Impl_Type of is parent.
12567 -- We need to initialize the attribute because if Def_Id is previously
12568 -- analyzed through a limited_with clause, it will have the attributes
12569 -- of an incomplete type, one of which is an Elist that overlaps the
12570 -- Packed_Array_Impl_Type field.
12572 Set_Packed_Array_Impl_Type (Def_Id, Empty);
12574 -- Build a freeze node if parent still needs one. Also make sure that
12575 -- the Depends_On_Private status is set because the subtype will need
12576 -- reprocessing at the time the base type does, and also we must set a
12577 -- conditional delay.
12579 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
12580 Conditional_Delay (Def_Id, T);
12581 end Constrain_Array;
12583 ------------------------------
12584 -- Constrain_Component_Type --
12585 ------------------------------
12587 function Constrain_Component_Type
12589 Constrained_Typ : Entity_Id;
12590 Related_Node : Node_Id;
12592 Constraints : Elist_Id) return Entity_Id
12594 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
12595 Compon_Type : constant Entity_Id := Etype (Comp);
12597 function Build_Constrained_Array_Type
12598 (Old_Type : Entity_Id) return Entity_Id;
12599 -- If Old_Type is an array type, one of whose indexes is constrained
12600 -- by a discriminant, build an Itype whose constraint replaces the
12601 -- discriminant with its value in the constraint.
12603 function Build_Constrained_Discriminated_Type
12604 (Old_Type : Entity_Id) return Entity_Id;
12605 -- Ditto for record components
12607 function Build_Constrained_Access_Type
12608 (Old_Type : Entity_Id) return Entity_Id;
12609 -- Ditto for access types. Makes use of previous two functions, to
12610 -- constrain designated type.
12612 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
12613 -- T is an array or discriminated type, C is a list of constraints
12614 -- that apply to T. This routine builds the constrained subtype.
12616 function Is_Discriminant (Expr : Node_Id) return Boolean;
12617 -- Returns True if Expr is a discriminant
12619 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
12620 -- Find the value of discriminant Discrim in Constraint
12622 -----------------------------------
12623 -- Build_Constrained_Access_Type --
12624 -----------------------------------
12626 function Build_Constrained_Access_Type
12627 (Old_Type : Entity_Id) return Entity_Id
12629 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
12631 Desig_Subtype : Entity_Id;
12635 -- if the original access type was not embedded in the enclosing
12636 -- type definition, there is no need to produce a new access
12637 -- subtype. In fact every access type with an explicit constraint
12638 -- generates an itype whose scope is the enclosing record.
12640 if not Is_Type (Scope (Old_Type)) then
12643 elsif Is_Array_Type (Desig_Type) then
12644 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
12646 elsif Has_Discriminants (Desig_Type) then
12648 -- This may be an access type to an enclosing record type for
12649 -- which we are constructing the constrained components. Return
12650 -- the enclosing record subtype. This is not always correct,
12651 -- but avoids infinite recursion. ???
12653 Desig_Subtype := Any_Type;
12655 for J in reverse 0 .. Scope_Stack.Last loop
12656 Scop := Scope_Stack.Table (J).Entity;
12659 and then Base_Type (Scop) = Base_Type (Desig_Type)
12661 Desig_Subtype := Scop;
12664 exit when not Is_Type (Scop);
12667 if Desig_Subtype = Any_Type then
12669 Build_Constrained_Discriminated_Type (Desig_Type);
12676 if Desig_Subtype /= Desig_Type then
12678 -- The Related_Node better be here or else we won't be able
12679 -- to attach new itypes to a node in the tree.
12681 pragma Assert (Present (Related_Node));
12683 Itype := Create_Itype (E_Access_Subtype, Related_Node);
12685 Set_Etype (Itype, Base_Type (Old_Type));
12686 Set_Size_Info (Itype, (Old_Type));
12687 Set_Directly_Designated_Type (Itype, Desig_Subtype);
12688 Set_Depends_On_Private (Itype, Has_Private_Component
12690 Set_Is_Access_Constant (Itype, Is_Access_Constant
12693 -- The new itype needs freezing when it depends on a not frozen
12694 -- type and the enclosing subtype needs freezing.
12696 if Has_Delayed_Freeze (Constrained_Typ)
12697 and then not Is_Frozen (Constrained_Typ)
12699 Conditional_Delay (Itype, Base_Type (Old_Type));
12707 end Build_Constrained_Access_Type;
12709 ----------------------------------
12710 -- Build_Constrained_Array_Type --
12711 ----------------------------------
12713 function Build_Constrained_Array_Type
12714 (Old_Type : Entity_Id) return Entity_Id
12718 Old_Index : Node_Id;
12719 Range_Node : Node_Id;
12720 Constr_List : List_Id;
12722 Need_To_Create_Itype : Boolean := False;
12725 Old_Index := First_Index (Old_Type);
12726 while Present (Old_Index) loop
12727 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
12729 if Is_Discriminant (Lo_Expr)
12731 Is_Discriminant (Hi_Expr)
12733 Need_To_Create_Itype := True;
12736 Next_Index (Old_Index);
12739 if Need_To_Create_Itype then
12740 Constr_List := New_List;
12742 Old_Index := First_Index (Old_Type);
12743 while Present (Old_Index) loop
12744 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
12746 if Is_Discriminant (Lo_Expr) then
12747 Lo_Expr := Get_Discr_Value (Lo_Expr);
12750 if Is_Discriminant (Hi_Expr) then
12751 Hi_Expr := Get_Discr_Value (Hi_Expr);
12756 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
12758 Append (Range_Node, To => Constr_List);
12760 Next_Index (Old_Index);
12763 return Build_Subtype (Old_Type, Constr_List);
12768 end Build_Constrained_Array_Type;
12770 ------------------------------------------
12771 -- Build_Constrained_Discriminated_Type --
12772 ------------------------------------------
12774 function Build_Constrained_Discriminated_Type
12775 (Old_Type : Entity_Id) return Entity_Id
12778 Constr_List : List_Id;
12779 Old_Constraint : Elmt_Id;
12781 Need_To_Create_Itype : Boolean := False;
12784 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
12785 while Present (Old_Constraint) loop
12786 Expr := Node (Old_Constraint);
12788 if Is_Discriminant (Expr) then
12789 Need_To_Create_Itype := True;
12792 Next_Elmt (Old_Constraint);
12795 if Need_To_Create_Itype then
12796 Constr_List := New_List;
12798 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
12799 while Present (Old_Constraint) loop
12800 Expr := Node (Old_Constraint);
12802 if Is_Discriminant (Expr) then
12803 Expr := Get_Discr_Value (Expr);
12806 Append (New_Copy_Tree (Expr), To => Constr_List);
12808 Next_Elmt (Old_Constraint);
12811 return Build_Subtype (Old_Type, Constr_List);
12816 end Build_Constrained_Discriminated_Type;
12818 -------------------
12819 -- Build_Subtype --
12820 -------------------
12822 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
12824 Subtyp_Decl : Node_Id;
12825 Def_Id : Entity_Id;
12826 Btyp : Entity_Id := Base_Type (T);
12829 -- The Related_Node better be here or else we won't be able to
12830 -- attach new itypes to a node in the tree.
12832 pragma Assert (Present (Related_Node));
12834 -- If the view of the component's type is incomplete or private
12835 -- with unknown discriminants, then the constraint must be applied
12836 -- to the full type.
12838 if Has_Unknown_Discriminants (Btyp)
12839 and then Present (Underlying_Type (Btyp))
12841 Btyp := Underlying_Type (Btyp);
12845 Make_Subtype_Indication (Loc,
12846 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
12847 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
12849 Def_Id := Create_Itype (Ekind (T), Related_Node);
12852 Make_Subtype_Declaration (Loc,
12853 Defining_Identifier => Def_Id,
12854 Subtype_Indication => Indic);
12856 Set_Parent (Subtyp_Decl, Parent (Related_Node));
12858 -- Itypes must be analyzed with checks off (see package Itypes)
12860 Analyze (Subtyp_Decl, Suppress => All_Checks);
12865 ---------------------
12866 -- Get_Discr_Value --
12867 ---------------------
12869 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
12874 -- The discriminant may be declared for the type, in which case we
12875 -- find it by iterating over the list of discriminants. If the
12876 -- discriminant is inherited from a parent type, it appears as the
12877 -- corresponding discriminant of the current type. This will be the
12878 -- case when constraining an inherited component whose constraint is
12879 -- given by a discriminant of the parent.
12881 D := First_Discriminant (Typ);
12882 E := First_Elmt (Constraints);
12884 while Present (D) loop
12885 if D = Entity (Discrim)
12886 or else D = CR_Discriminant (Entity (Discrim))
12887 or else Corresponding_Discriminant (D) = Entity (Discrim)
12892 Next_Discriminant (D);
12896 -- The Corresponding_Discriminant mechanism is incomplete, because
12897 -- the correspondence between new and old discriminants is not one
12898 -- to one: one new discriminant can constrain several old ones. In
12899 -- that case, scan sequentially the stored_constraint, the list of
12900 -- discriminants of the parents, and the constraints.
12902 -- Previous code checked for the present of the Stored_Constraint
12903 -- list for the derived type, but did not use it at all. Should it
12904 -- be present when the component is a discriminated task type?
12906 if Is_Derived_Type (Typ)
12907 and then Scope (Entity (Discrim)) = Etype (Typ)
12909 D := First_Discriminant (Etype (Typ));
12910 E := First_Elmt (Constraints);
12911 while Present (D) loop
12912 if D = Entity (Discrim) then
12916 Next_Discriminant (D);
12921 -- Something is wrong if we did not find the value
12923 raise Program_Error;
12924 end Get_Discr_Value;
12926 ---------------------
12927 -- Is_Discriminant --
12928 ---------------------
12930 function Is_Discriminant (Expr : Node_Id) return Boolean is
12931 Discrim_Scope : Entity_Id;
12934 if Denotes_Discriminant (Expr) then
12935 Discrim_Scope := Scope (Entity (Expr));
12937 -- Either we have a reference to one of Typ's discriminants,
12939 pragma Assert (Discrim_Scope = Typ
12941 -- or to the discriminants of the parent type, in the case
12942 -- of a derivation of a tagged type with variants.
12944 or else Discrim_Scope = Etype (Typ)
12945 or else Full_View (Discrim_Scope) = Etype (Typ)
12947 -- or same as above for the case where the discriminants
12948 -- were declared in Typ's private view.
12950 or else (Is_Private_Type (Discrim_Scope)
12951 and then Chars (Discrim_Scope) = Chars (Typ))
12953 -- or else we are deriving from the full view and the
12954 -- discriminant is declared in the private entity.
12956 or else (Is_Private_Type (Typ)
12957 and then Chars (Discrim_Scope) = Chars (Typ))
12959 -- Or we are constrained the corresponding record of a
12960 -- synchronized type that completes a private declaration.
12962 or else (Is_Concurrent_Record_Type (Typ)
12964 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
12966 -- or we have a class-wide type, in which case make sure the
12967 -- discriminant found belongs to the root type.
12969 or else (Is_Class_Wide_Type (Typ)
12970 and then Etype (Typ) = Discrim_Scope));
12975 -- In all other cases we have something wrong
12978 end Is_Discriminant;
12980 -- Start of processing for Constrain_Component_Type
12983 if Nkind (Parent (Comp)) = N_Component_Declaration
12984 and then Comes_From_Source (Parent (Comp))
12985 and then Comes_From_Source
12986 (Subtype_Indication (Component_Definition (Parent (Comp))))
12989 (Subtype_Indication (Component_Definition (Parent (Comp))))
12991 return Compon_Type;
12993 elsif Is_Array_Type (Compon_Type) then
12994 return Build_Constrained_Array_Type (Compon_Type);
12996 elsif Has_Discriminants (Compon_Type) then
12997 return Build_Constrained_Discriminated_Type (Compon_Type);
12999 elsif Is_Access_Type (Compon_Type) then
13000 return Build_Constrained_Access_Type (Compon_Type);
13003 return Compon_Type;
13005 end Constrain_Component_Type;
13007 --------------------------
13008 -- Constrain_Concurrent --
13009 --------------------------
13011 -- For concurrent types, the associated record value type carries the same
13012 -- discriminants, so when we constrain a concurrent type, we must constrain
13013 -- the corresponding record type as well.
13015 procedure Constrain_Concurrent
13016 (Def_Id : in out Entity_Id;
13018 Related_Nod : Node_Id;
13019 Related_Id : Entity_Id;
13020 Suffix : Character)
13022 -- Retrieve Base_Type to ensure getting to the concurrent type in the
13023 -- case of a private subtype (needed when only doing semantic analysis).
13025 T_Ent : Entity_Id := Base_Type (Entity (Subtype_Mark (SI)));
13029 if Is_Access_Type (T_Ent) then
13030 T_Ent := Designated_Type (T_Ent);
13033 T_Val := Corresponding_Record_Type (T_Ent);
13035 if Present (T_Val) then
13037 if No (Def_Id) then
13038 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
13040 -- Elaborate itype now, as it may be used in a subsequent
13041 -- synchronized operation in another scope.
13043 if Nkind (Related_Nod) = N_Full_Type_Declaration then
13044 Build_Itype_Reference (Def_Id, Related_Nod);
13048 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
13050 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
13051 Set_Corresponding_Record_Type (Def_Id,
13052 Constrain_Corresponding_Record (Def_Id, T_Val, Related_Nod));
13055 -- If there is no associated record, expansion is disabled and this
13056 -- is a generic context. Create a subtype in any case, so that
13057 -- semantic analysis can proceed.
13059 if No (Def_Id) then
13060 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
13063 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
13065 end Constrain_Concurrent;
13067 ------------------------------------
13068 -- Constrain_Corresponding_Record --
13069 ------------------------------------
13071 function Constrain_Corresponding_Record
13072 (Prot_Subt : Entity_Id;
13073 Corr_Rec : Entity_Id;
13074 Related_Nod : Node_Id) return Entity_Id
13076 T_Sub : constant Entity_Id :=
13077 Create_Itype (E_Record_Subtype, Related_Nod, Corr_Rec, 'C');
13080 Set_Etype (T_Sub, Corr_Rec);
13081 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
13082 Set_Is_Constrained (T_Sub, True);
13083 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
13084 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
13086 if Has_Discriminants (Prot_Subt) then -- False only if errors.
13087 Set_Discriminant_Constraint
13088 (T_Sub, Discriminant_Constraint (Prot_Subt));
13089 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
13090 Create_Constrained_Components
13091 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
13094 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
13096 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
13097 Conditional_Delay (T_Sub, Corr_Rec);
13100 -- This is a component subtype: it will be frozen in the context of
13101 -- the enclosing record's init_proc, so that discriminant references
13102 -- are resolved to discriminals. (Note: we used to skip freezing
13103 -- altogether in that case, which caused errors downstream for
13104 -- components of a bit packed array type).
13106 Set_Has_Delayed_Freeze (T_Sub);
13110 end Constrain_Corresponding_Record;
13112 -----------------------
13113 -- Constrain_Decimal --
13114 -----------------------
13116 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
13117 T : constant Entity_Id := Entity (Subtype_Mark (S));
13118 C : constant Node_Id := Constraint (S);
13119 Loc : constant Source_Ptr := Sloc (C);
13120 Range_Expr : Node_Id;
13121 Digits_Expr : Node_Id;
13126 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
13128 if Nkind (C) = N_Range_Constraint then
13129 Range_Expr := Range_Expression (C);
13130 Digits_Val := Digits_Value (T);
13133 pragma Assert (Nkind (C) = N_Digits_Constraint);
13135 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
13137 Digits_Expr := Digits_Expression (C);
13138 Analyze_And_Resolve (Digits_Expr, Any_Integer);
13140 Check_Digits_Expression (Digits_Expr);
13141 Digits_Val := Expr_Value (Digits_Expr);
13143 if Digits_Val > Digits_Value (T) then
13145 ("digits expression is incompatible with subtype", C);
13146 Digits_Val := Digits_Value (T);
13149 if Present (Range_Constraint (C)) then
13150 Range_Expr := Range_Expression (Range_Constraint (C));
13152 Range_Expr := Empty;
13156 Set_Etype (Def_Id, Base_Type (T));
13157 Set_Size_Info (Def_Id, (T));
13158 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13159 Set_Delta_Value (Def_Id, Delta_Value (T));
13160 Set_Scale_Value (Def_Id, Scale_Value (T));
13161 Set_Small_Value (Def_Id, Small_Value (T));
13162 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
13163 Set_Digits_Value (Def_Id, Digits_Val);
13165 -- Manufacture range from given digits value if no range present
13167 if No (Range_Expr) then
13168 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
13172 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
13174 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
13177 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
13178 Set_Discrete_RM_Size (Def_Id);
13180 -- Unconditionally delay the freeze, since we cannot set size
13181 -- information in all cases correctly until the freeze point.
13183 Set_Has_Delayed_Freeze (Def_Id);
13184 end Constrain_Decimal;
13186 ----------------------------------
13187 -- Constrain_Discriminated_Type --
13188 ----------------------------------
13190 procedure Constrain_Discriminated_Type
13191 (Def_Id : Entity_Id;
13193 Related_Nod : Node_Id;
13194 For_Access : Boolean := False)
13196 E : Entity_Id := Entity (Subtype_Mark (S));
13199 procedure Fixup_Bad_Constraint;
13200 -- Called after finding a bad constraint, and after having posted an
13201 -- appropriate error message. The goal is to leave type Def_Id in as
13202 -- reasonable state as possible.
13204 --------------------------
13205 -- Fixup_Bad_Constraint --
13206 --------------------------
13208 procedure Fixup_Bad_Constraint is
13210 -- Set a reasonable Ekind for the entity. For an incomplete type,
13211 -- we can't do much, but for other types, we can set the proper
13212 -- corresponding subtype kind.
13214 if Ekind (T) = E_Incomplete_Type then
13215 Set_Ekind (Def_Id, Ekind (T));
13217 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
13220 -- Set Etype to the known type, to reduce chances of cascaded errors
13222 Set_Etype (Def_Id, E);
13223 Set_Error_Posted (Def_Id);
13224 end Fixup_Bad_Constraint;
13229 Constr : Elist_Id := New_Elmt_List;
13231 -- Start of processing for Constrain_Discriminated_Type
13234 C := Constraint (S);
13236 -- A discriminant constraint is only allowed in a subtype indication,
13237 -- after a subtype mark. This subtype mark must denote either a type
13238 -- with discriminants, or an access type whose designated type is a
13239 -- type with discriminants. A discriminant constraint specifies the
13240 -- values of these discriminants (RM 3.7.2(5)).
13242 T := Base_Type (Entity (Subtype_Mark (S)));
13244 if Is_Access_Type (T) then
13245 T := Designated_Type (T);
13248 -- In an instance it may be necessary to retrieve the full view of a
13249 -- type with unknown discriminants, or a full view with defaulted
13250 -- discriminants. In other contexts the constraint is illegal.
13253 and then Is_Private_Type (T)
13254 and then Present (Full_View (T))
13256 (Has_Unknown_Discriminants (T)
13258 (not Has_Discriminants (T)
13259 and then Has_Discriminants (Full_View (T))
13260 and then Present (Discriminant_Default_Value
13261 (First_Discriminant (Full_View (T))))))
13263 T := Full_View (T);
13264 E := Full_View (E);
13267 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal. Avoid
13268 -- generating an error for access-to-incomplete subtypes.
13270 if Ada_Version >= Ada_2005
13271 and then Ekind (T) = E_Incomplete_Type
13272 and then Nkind (Parent (S)) = N_Subtype_Declaration
13273 and then not Is_Itype (Def_Id)
13275 -- A little sanity check: emit an error message if the type has
13276 -- discriminants to begin with. Type T may be a regular incomplete
13277 -- type or imported via a limited with clause.
13279 if Has_Discriminants (T)
13280 or else (From_Limited_With (T)
13281 and then Present (Non_Limited_View (T))
13282 and then Nkind (Parent (Non_Limited_View (T))) =
13283 N_Full_Type_Declaration
13284 and then Present (Discriminant_Specifications
13285 (Parent (Non_Limited_View (T)))))
13288 ("(Ada 2005) incomplete subtype may not be constrained", C);
13290 Error_Msg_N ("invalid constraint: type has no discriminant", C);
13293 Fixup_Bad_Constraint;
13296 -- Check that the type has visible discriminants. The type may be
13297 -- a private type with unknown discriminants whose full view has
13298 -- discriminants which are invisible.
13300 elsif not Has_Discriminants (T)
13302 (Has_Unknown_Discriminants (T)
13303 and then Is_Private_Type (T))
13305 Error_Msg_N ("invalid constraint: type has no discriminant", C);
13306 Fixup_Bad_Constraint;
13309 elsif Is_Constrained (E)
13310 or else (Ekind (E) = E_Class_Wide_Subtype
13311 and then Present (Discriminant_Constraint (E)))
13313 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
13314 Fixup_Bad_Constraint;
13318 -- T may be an unconstrained subtype (e.g. a generic actual). Constraint
13319 -- applies to the base type.
13321 T := Base_Type (T);
13323 Constr := Build_Discriminant_Constraints (T, S);
13325 -- If the list returned was empty we had an error in building the
13326 -- discriminant constraint. We have also already signalled an error
13327 -- in the incomplete type case
13329 if Is_Empty_Elmt_List (Constr) then
13330 Fixup_Bad_Constraint;
13334 Build_Discriminated_Subtype (T, Def_Id, Constr, Related_Nod, For_Access);
13335 end Constrain_Discriminated_Type;
13337 ---------------------------
13338 -- Constrain_Enumeration --
13339 ---------------------------
13341 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
13342 T : constant Entity_Id := Entity (Subtype_Mark (S));
13343 C : constant Node_Id := Constraint (S);
13346 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13348 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
13350 Set_Etype (Def_Id, Base_Type (T));
13351 Set_Size_Info (Def_Id, (T));
13352 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13353 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13355 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13357 Set_Discrete_RM_Size (Def_Id);
13358 end Constrain_Enumeration;
13360 ----------------------
13361 -- Constrain_Float --
13362 ----------------------
13364 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
13365 T : constant Entity_Id := Entity (Subtype_Mark (S));
13371 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
13373 Set_Etype (Def_Id, Base_Type (T));
13374 Set_Size_Info (Def_Id, (T));
13375 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13377 -- Process the constraint
13379 C := Constraint (S);
13381 -- Digits constraint present
13383 if Nkind (C) = N_Digits_Constraint then
13385 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
13386 Check_Restriction (No_Obsolescent_Features, C);
13388 if Warn_On_Obsolescent_Feature then
13390 ("subtype digits constraint is an " &
13391 "obsolescent feature (RM J.3(8))?j?", C);
13394 D := Digits_Expression (C);
13395 Analyze_And_Resolve (D, Any_Integer);
13396 Check_Digits_Expression (D);
13397 Set_Digits_Value (Def_Id, Expr_Value (D));
13399 -- Check that digits value is in range. Obviously we can do this
13400 -- at compile time, but it is strictly a runtime check, and of
13401 -- course there is an ACVC test that checks this.
13403 if Digits_Value (Def_Id) > Digits_Value (T) then
13404 Error_Msg_Uint_1 := Digits_Value (T);
13405 Error_Msg_N ("??digits value is too large, maximum is ^", D);
13407 Make_Raise_Constraint_Error (Sloc (D),
13408 Reason => CE_Range_Check_Failed);
13409 Insert_Action (Declaration_Node (Def_Id), Rais);
13412 C := Range_Constraint (C);
13414 -- No digits constraint present
13417 Set_Digits_Value (Def_Id, Digits_Value (T));
13420 -- Range constraint present
13422 if Nkind (C) = N_Range_Constraint then
13423 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13425 -- No range constraint present
13428 pragma Assert (No (C));
13429 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13432 Set_Is_Constrained (Def_Id);
13433 end Constrain_Float;
13435 ---------------------
13436 -- Constrain_Index --
13437 ---------------------
13439 procedure Constrain_Index
13442 Related_Nod : Node_Id;
13443 Related_Id : Entity_Id;
13444 Suffix : Character;
13445 Suffix_Index : Nat)
13447 Def_Id : Entity_Id;
13448 R : Node_Id := Empty;
13449 T : constant Entity_Id := Etype (Index);
13453 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
13454 Set_Etype (Def_Id, Base_Type (T));
13456 if Nkind (S) = N_Range
13458 (Nkind (S) = N_Attribute_Reference
13459 and then Attribute_Name (S) = Name_Range)
13461 -- A Range attribute will be transformed into N_Range by Resolve
13467 Process_Range_Expr_In_Decl (R, T);
13469 if not Error_Posted (S)
13471 (Nkind (S) /= N_Range
13472 or else not Covers (T, (Etype (Low_Bound (S))))
13473 or else not Covers (T, (Etype (High_Bound (S)))))
13475 if Base_Type (T) /= Any_Type
13476 and then Etype (Low_Bound (S)) /= Any_Type
13477 and then Etype (High_Bound (S)) /= Any_Type
13479 Error_Msg_N ("range expected", S);
13483 elsif Nkind (S) = N_Subtype_Indication then
13485 -- The parser has verified that this is a discrete indication
13487 Resolve_Discrete_Subtype_Indication (S, T);
13488 Bad_Predicated_Subtype_Use
13489 ("subtype& has predicate, not allowed in index constraint",
13490 S, Entity (Subtype_Mark (S)));
13492 R := Range_Expression (Constraint (S));
13494 -- Capture values of bounds and generate temporaries for them if
13495 -- needed, since checks may cause duplication of the expressions
13496 -- which must not be reevaluated.
13498 -- The forced evaluation removes side effects from expressions, which
13499 -- should occur also in GNATprove mode. Otherwise, we end up with
13500 -- unexpected insertions of actions at places where this is not
13501 -- supposed to occur, e.g. on default parameters of a call.
13503 if Expander_Active or GNATprove_Mode then
13505 (Low_Bound (R), Related_Id => Def_Id, Is_Low_Bound => True);
13507 (High_Bound (R), Related_Id => Def_Id, Is_High_Bound => True);
13510 elsif Nkind (S) = N_Discriminant_Association then
13512 -- Syntactically valid in subtype indication
13514 Error_Msg_N ("invalid index constraint", S);
13515 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13518 -- Subtype_Mark case, no anonymous subtypes to construct
13523 if Is_Entity_Name (S) then
13524 if not Is_Type (Entity (S)) then
13525 Error_Msg_N ("expect subtype mark for index constraint", S);
13527 elsif Base_Type (Entity (S)) /= Base_Type (T) then
13528 Wrong_Type (S, Base_Type (T));
13530 -- Check error of subtype with predicate in index constraint
13533 Bad_Predicated_Subtype_Use
13534 ("subtype& has predicate, not allowed in index constraint",
13541 Error_Msg_N ("invalid index constraint", S);
13542 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13547 -- Complete construction of the Itype
13549 if Is_Modular_Integer_Type (T) then
13550 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13552 elsif Is_Integer_Type (T) then
13553 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13556 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13557 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13558 Set_First_Literal (Def_Id, First_Literal (T));
13561 Set_Size_Info (Def_Id, (T));
13562 Set_RM_Size (Def_Id, RM_Size (T));
13563 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13565 Set_Scalar_Range (Def_Id, R);
13567 Set_Etype (S, Def_Id);
13568 Set_Discrete_RM_Size (Def_Id);
13569 end Constrain_Index;
13571 -----------------------
13572 -- Constrain_Integer --
13573 -----------------------
13575 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
13576 T : constant Entity_Id := Entity (Subtype_Mark (S));
13577 C : constant Node_Id := Constraint (S);
13580 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13582 if Is_Modular_Integer_Type (T) then
13583 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13585 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13588 Set_Etype (Def_Id, Base_Type (T));
13589 Set_Size_Info (Def_Id, (T));
13590 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13591 Set_Discrete_RM_Size (Def_Id);
13592 end Constrain_Integer;
13594 ------------------------------
13595 -- Constrain_Ordinary_Fixed --
13596 ------------------------------
13598 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
13599 T : constant Entity_Id := Entity (Subtype_Mark (S));
13605 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
13606 Set_Etype (Def_Id, Base_Type (T));
13607 Set_Size_Info (Def_Id, (T));
13608 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13609 Set_Small_Value (Def_Id, Small_Value (T));
13611 -- Process the constraint
13613 C := Constraint (S);
13615 -- Delta constraint present
13617 if Nkind (C) = N_Delta_Constraint then
13619 Check_SPARK_05_Restriction ("delta constraint is not allowed", S);
13620 Check_Restriction (No_Obsolescent_Features, C);
13622 if Warn_On_Obsolescent_Feature then
13624 ("subtype delta constraint is an " &
13625 "obsolescent feature (RM J.3(7))?j?");
13628 D := Delta_Expression (C);
13629 Analyze_And_Resolve (D, Any_Real);
13630 Check_Delta_Expression (D);
13631 Set_Delta_Value (Def_Id, Expr_Value_R (D));
13633 -- Check that delta value is in range. Obviously we can do this
13634 -- at compile time, but it is strictly a runtime check, and of
13635 -- course there is an ACVC test that checks this.
13637 if Delta_Value (Def_Id) < Delta_Value (T) then
13638 Error_Msg_N ("??delta value is too small", D);
13640 Make_Raise_Constraint_Error (Sloc (D),
13641 Reason => CE_Range_Check_Failed);
13642 Insert_Action (Declaration_Node (Def_Id), Rais);
13645 C := Range_Constraint (C);
13647 -- No delta constraint present
13650 Set_Delta_Value (Def_Id, Delta_Value (T));
13653 -- Range constraint present
13655 if Nkind (C) = N_Range_Constraint then
13656 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13658 -- No range constraint present
13661 pragma Assert (No (C));
13662 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13665 Set_Discrete_RM_Size (Def_Id);
13667 -- Unconditionally delay the freeze, since we cannot set size
13668 -- information in all cases correctly until the freeze point.
13670 Set_Has_Delayed_Freeze (Def_Id);
13671 end Constrain_Ordinary_Fixed;
13673 -----------------------
13674 -- Contain_Interface --
13675 -----------------------
13677 function Contain_Interface
13678 (Iface : Entity_Id;
13679 Ifaces : Elist_Id) return Boolean
13681 Iface_Elmt : Elmt_Id;
13684 if Present (Ifaces) then
13685 Iface_Elmt := First_Elmt (Ifaces);
13686 while Present (Iface_Elmt) loop
13687 if Node (Iface_Elmt) = Iface then
13691 Next_Elmt (Iface_Elmt);
13696 end Contain_Interface;
13698 ---------------------------
13699 -- Convert_Scalar_Bounds --
13700 ---------------------------
13702 procedure Convert_Scalar_Bounds
13704 Parent_Type : Entity_Id;
13705 Derived_Type : Entity_Id;
13708 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
13715 -- Defend against previous errors
13717 if No (Scalar_Range (Derived_Type)) then
13718 Check_Error_Detected;
13722 Lo := Build_Scalar_Bound
13723 (Type_Low_Bound (Derived_Type),
13724 Parent_Type, Implicit_Base);
13726 Hi := Build_Scalar_Bound
13727 (Type_High_Bound (Derived_Type),
13728 Parent_Type, Implicit_Base);
13735 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
13737 Set_Parent (Rng, N);
13738 Set_Scalar_Range (Derived_Type, Rng);
13740 -- Analyze the bounds
13742 Analyze_And_Resolve (Lo, Implicit_Base);
13743 Analyze_And_Resolve (Hi, Implicit_Base);
13745 -- Analyze the range itself, except that we do not analyze it if
13746 -- the bounds are real literals, and we have a fixed-point type.
13747 -- The reason for this is that we delay setting the bounds in this
13748 -- case till we know the final Small and Size values (see circuit
13749 -- in Freeze.Freeze_Fixed_Point_Type for further details).
13751 if Is_Fixed_Point_Type (Parent_Type)
13752 and then Nkind (Lo) = N_Real_Literal
13753 and then Nkind (Hi) = N_Real_Literal
13757 -- Here we do the analysis of the range
13759 -- Note: we do this manually, since if we do a normal Analyze and
13760 -- Resolve call, there are problems with the conversions used for
13761 -- the derived type range.
13764 Set_Etype (Rng, Implicit_Base);
13765 Set_Analyzed (Rng, True);
13767 end Convert_Scalar_Bounds;
13769 -------------------
13770 -- Copy_And_Swap --
13771 -------------------
13773 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
13775 -- Initialize new full declaration entity by copying the pertinent
13776 -- fields of the corresponding private declaration entity.
13778 -- We temporarily set Ekind to a value appropriate for a type to
13779 -- avoid assert failures in Einfo from checking for setting type
13780 -- attributes on something that is not a type. Ekind (Priv) is an
13781 -- appropriate choice, since it allowed the attributes to be set
13782 -- in the first place. This Ekind value will be modified later.
13784 Set_Ekind (Full, Ekind (Priv));
13786 -- Also set Etype temporarily to Any_Type, again, in the absence
13787 -- of errors, it will be properly reset, and if there are errors,
13788 -- then we want a value of Any_Type to remain.
13790 Set_Etype (Full, Any_Type);
13792 -- Now start copying attributes
13794 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
13796 if Has_Discriminants (Full) then
13797 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
13798 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
13801 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
13802 Set_Homonym (Full, Homonym (Priv));
13803 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
13804 Set_Is_Public (Full, Is_Public (Priv));
13805 Set_Is_Pure (Full, Is_Pure (Priv));
13806 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
13807 Set_Has_Pragma_Unmodified (Full, Has_Pragma_Unmodified (Priv));
13808 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
13809 Set_Has_Pragma_Unreferenced_Objects
13810 (Full, Has_Pragma_Unreferenced_Objects
13813 Conditional_Delay (Full, Priv);
13815 if Is_Tagged_Type (Full) then
13816 Set_Direct_Primitive_Operations
13817 (Full, Direct_Primitive_Operations (Priv));
13818 Set_No_Tagged_Streams_Pragma
13819 (Full, No_Tagged_Streams_Pragma (Priv));
13821 if Is_Base_Type (Priv) then
13822 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
13826 Set_Is_Volatile (Full, Is_Volatile (Priv));
13827 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
13828 Set_Scope (Full, Scope (Priv));
13829 Set_Next_Entity (Full, Next_Entity (Priv));
13830 Set_First_Entity (Full, First_Entity (Priv));
13831 Set_Last_Entity (Full, Last_Entity (Priv));
13833 -- If access types have been recorded for later handling, keep them in
13834 -- the full view so that they get handled when the full view freeze
13835 -- node is expanded.
13837 if Present (Freeze_Node (Priv))
13838 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
13840 Ensure_Freeze_Node (Full);
13841 Set_Access_Types_To_Process
13842 (Freeze_Node (Full),
13843 Access_Types_To_Process (Freeze_Node (Priv)));
13846 -- Swap the two entities. Now Private is the full type entity and Full
13847 -- is the private one. They will be swapped back at the end of the
13848 -- private part. This swapping ensures that the entity that is visible
13849 -- in the private part is the full declaration.
13851 Exchange_Entities (Priv, Full);
13852 Append_Entity (Full, Scope (Full));
13855 -------------------------------------
13856 -- Copy_Array_Base_Type_Attributes --
13857 -------------------------------------
13859 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
13861 Set_Component_Alignment (T1, Component_Alignment (T2));
13862 Set_Component_Type (T1, Component_Type (T2));
13863 Set_Component_Size (T1, Component_Size (T2));
13864 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
13865 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
13866 Propagate_Concurrent_Flags (T1, T2);
13867 Set_Is_Packed (T1, Is_Packed (T2));
13868 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
13869 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
13870 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
13871 end Copy_Array_Base_Type_Attributes;
13873 -----------------------------------
13874 -- Copy_Array_Subtype_Attributes --
13875 -----------------------------------
13877 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
13879 Set_Size_Info (T1, T2);
13881 Set_First_Index (T1, First_Index (T2));
13882 Set_Is_Aliased (T1, Is_Aliased (T2));
13883 Set_Is_Volatile (T1, Is_Volatile (T2));
13884 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
13885 Set_Is_Constrained (T1, Is_Constrained (T2));
13886 Set_Depends_On_Private (T1, Has_Private_Component (T2));
13887 Inherit_Rep_Item_Chain (T1, T2);
13888 Set_Convention (T1, Convention (T2));
13889 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
13890 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
13891 Set_Packed_Array_Impl_Type (T1, Packed_Array_Impl_Type (T2));
13892 end Copy_Array_Subtype_Attributes;
13894 -----------------------------------
13895 -- Create_Constrained_Components --
13896 -----------------------------------
13898 procedure Create_Constrained_Components
13900 Decl_Node : Node_Id;
13902 Constraints : Elist_Id)
13904 Loc : constant Source_Ptr := Sloc (Subt);
13905 Comp_List : constant Elist_Id := New_Elmt_List;
13906 Parent_Type : constant Entity_Id := Etype (Typ);
13907 Assoc_List : constant List_Id := New_List;
13908 Discr_Val : Elmt_Id;
13912 Is_Static : Boolean := True;
13914 procedure Collect_Fixed_Components (Typ : Entity_Id);
13915 -- Collect parent type components that do not appear in a variant part
13917 procedure Create_All_Components;
13918 -- Iterate over Comp_List to create the components of the subtype
13920 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
13921 -- Creates a new component from Old_Compon, copying all the fields from
13922 -- it, including its Etype, inserts the new component in the Subt entity
13923 -- chain and returns the new component.
13925 function Is_Variant_Record (T : Entity_Id) return Boolean;
13926 -- If true, and discriminants are static, collect only components from
13927 -- variants selected by discriminant values.
13929 ------------------------------
13930 -- Collect_Fixed_Components --
13931 ------------------------------
13933 procedure Collect_Fixed_Components (Typ : Entity_Id) is
13935 -- Build association list for discriminants, and find components of the
13936 -- variant part selected by the values of the discriminants.
13938 Old_C := First_Discriminant (Typ);
13939 Discr_Val := First_Elmt (Constraints);
13940 while Present (Old_C) loop
13941 Append_To (Assoc_List,
13942 Make_Component_Association (Loc,
13943 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
13944 Expression => New_Copy (Node (Discr_Val))));
13946 Next_Elmt (Discr_Val);
13947 Next_Discriminant (Old_C);
13950 -- The tag and the possible parent component are unconditionally in
13953 if Is_Tagged_Type (Typ) or else Has_Controlled_Component (Typ) then
13954 Old_C := First_Component (Typ);
13955 while Present (Old_C) loop
13956 if Nam_In (Chars (Old_C), Name_uTag, Name_uParent) then
13957 Append_Elmt (Old_C, Comp_List);
13960 Next_Component (Old_C);
13963 end Collect_Fixed_Components;
13965 ---------------------------
13966 -- Create_All_Components --
13967 ---------------------------
13969 procedure Create_All_Components is
13973 Comp := First_Elmt (Comp_List);
13974 while Present (Comp) loop
13975 Old_C := Node (Comp);
13976 New_C := Create_Component (Old_C);
13980 Constrain_Component_Type
13981 (Old_C, Subt, Decl_Node, Typ, Constraints));
13982 Set_Is_Public (New_C, Is_Public (Subt));
13986 end Create_All_Components;
13988 ----------------------
13989 -- Create_Component --
13990 ----------------------
13992 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
13993 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
13996 if Ekind (Old_Compon) = E_Discriminant
13997 and then Is_Completely_Hidden (Old_Compon)
13999 -- This is a shadow discriminant created for a discriminant of
14000 -- the parent type, which needs to be present in the subtype.
14001 -- Give the shadow discriminant an internal name that cannot
14002 -- conflict with that of visible components.
14004 Set_Chars (New_Compon, New_Internal_Name ('C'));
14007 -- Set the parent so we have a proper link for freezing etc. This is
14008 -- not a real parent pointer, since of course our parent does not own
14009 -- up to us and reference us, we are an illegitimate child of the
14010 -- original parent.
14012 Set_Parent (New_Compon, Parent (Old_Compon));
14014 -- If the old component's Esize was already determined and is a
14015 -- static value, then the new component simply inherits it. Otherwise
14016 -- the old component's size may require run-time determination, but
14017 -- the new component's size still might be statically determinable
14018 -- (if, for example it has a static constraint). In that case we want
14019 -- Layout_Type to recompute the component's size, so we reset its
14020 -- size and positional fields.
14022 if Frontend_Layout_On_Target
14023 and then not Known_Static_Esize (Old_Compon)
14025 Set_Esize (New_Compon, Uint_0);
14026 Init_Normalized_First_Bit (New_Compon);
14027 Init_Normalized_Position (New_Compon);
14028 Init_Normalized_Position_Max (New_Compon);
14031 -- We do not want this node marked as Comes_From_Source, since
14032 -- otherwise it would get first class status and a separate cross-
14033 -- reference line would be generated. Illegitimate children do not
14034 -- rate such recognition.
14036 Set_Comes_From_Source (New_Compon, False);
14038 -- But it is a real entity, and a birth certificate must be properly
14039 -- registered by entering it into the entity list.
14041 Enter_Name (New_Compon);
14044 end Create_Component;
14046 -----------------------
14047 -- Is_Variant_Record --
14048 -----------------------
14050 function Is_Variant_Record (T : Entity_Id) return Boolean is
14052 return Nkind (Parent (T)) = N_Full_Type_Declaration
14053 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
14054 and then Present (Component_List (Type_Definition (Parent (T))))
14057 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
14058 end Is_Variant_Record;
14060 -- Start of processing for Create_Constrained_Components
14063 pragma Assert (Subt /= Base_Type (Subt));
14064 pragma Assert (Typ = Base_Type (Typ));
14066 Set_First_Entity (Subt, Empty);
14067 Set_Last_Entity (Subt, Empty);
14069 -- Check whether constraint is fully static, in which case we can
14070 -- optimize the list of components.
14072 Discr_Val := First_Elmt (Constraints);
14073 while Present (Discr_Val) loop
14074 if not Is_OK_Static_Expression (Node (Discr_Val)) then
14075 Is_Static := False;
14079 Next_Elmt (Discr_Val);
14082 Set_Has_Static_Discriminants (Subt, Is_Static);
14086 -- Inherit the discriminants of the parent type
14088 Add_Discriminants : declare
14094 Old_C := First_Discriminant (Typ);
14096 while Present (Old_C) loop
14097 Num_Disc := Num_Disc + 1;
14098 New_C := Create_Component (Old_C);
14099 Set_Is_Public (New_C, Is_Public (Subt));
14100 Next_Discriminant (Old_C);
14103 -- For an untagged derived subtype, the number of discriminants may
14104 -- be smaller than the number of inherited discriminants, because
14105 -- several of them may be renamed by a single new discriminant or
14106 -- constrained. In this case, add the hidden discriminants back into
14107 -- the subtype, because they need to be present if the optimizer of
14108 -- the GCC 4.x back-end decides to break apart assignments between
14109 -- objects using the parent view into member-wise assignments.
14113 if Is_Derived_Type (Typ)
14114 and then not Is_Tagged_Type (Typ)
14116 Old_C := First_Stored_Discriminant (Typ);
14118 while Present (Old_C) loop
14119 Num_Gird := Num_Gird + 1;
14120 Next_Stored_Discriminant (Old_C);
14124 if Num_Gird > Num_Disc then
14126 -- Find out multiple uses of new discriminants, and add hidden
14127 -- components for the extra renamed discriminants. We recognize
14128 -- multiple uses through the Corresponding_Discriminant of a
14129 -- new discriminant: if it constrains several old discriminants,
14130 -- this field points to the last one in the parent type. The
14131 -- stored discriminants of the derived type have the same name
14132 -- as those of the parent.
14136 New_Discr : Entity_Id;
14137 Old_Discr : Entity_Id;
14140 Constr := First_Elmt (Stored_Constraint (Typ));
14141 Old_Discr := First_Stored_Discriminant (Typ);
14142 while Present (Constr) loop
14143 if Is_Entity_Name (Node (Constr))
14144 and then Ekind (Entity (Node (Constr))) = E_Discriminant
14146 New_Discr := Entity (Node (Constr));
14148 if Chars (Corresponding_Discriminant (New_Discr)) /=
14151 -- The new discriminant has been used to rename a
14152 -- subsequent old discriminant. Introduce a shadow
14153 -- component for the current old discriminant.
14155 New_C := Create_Component (Old_Discr);
14156 Set_Original_Record_Component (New_C, Old_Discr);
14160 -- The constraint has eliminated the old discriminant.
14161 -- Introduce a shadow component.
14163 New_C := Create_Component (Old_Discr);
14164 Set_Original_Record_Component (New_C, Old_Discr);
14167 Next_Elmt (Constr);
14168 Next_Stored_Discriminant (Old_Discr);
14172 end Add_Discriminants;
14175 and then Is_Variant_Record (Typ)
14177 Collect_Fixed_Components (Typ);
14179 Gather_Components (
14181 Component_List (Type_Definition (Parent (Typ))),
14182 Governed_By => Assoc_List,
14184 Report_Errors => Errors);
14185 pragma Assert (not Errors);
14187 Create_All_Components;
14189 -- If the subtype declaration is created for a tagged type derivation
14190 -- with constraints, we retrieve the record definition of the parent
14191 -- type to select the components of the proper variant.
14194 and then Is_Tagged_Type (Typ)
14195 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
14197 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
14198 and then Is_Variant_Record (Parent_Type)
14200 Collect_Fixed_Components (Typ);
14204 Component_List (Type_Definition (Parent (Parent_Type))),
14205 Governed_By => Assoc_List,
14207 Report_Errors => Errors);
14209 -- Note: previously there was a check at this point that no errors
14210 -- were detected. As a consequence of AI05-220 there may be an error
14211 -- if an inherited discriminant that controls a variant has a non-
14212 -- static constraint.
14214 -- If the tagged derivation has a type extension, collect all the
14215 -- new components therein.
14217 if Present (Record_Extension_Part (Type_Definition (Parent (Typ))))
14219 Old_C := First_Component (Typ);
14220 while Present (Old_C) loop
14221 if Original_Record_Component (Old_C) = Old_C
14222 and then Chars (Old_C) /= Name_uTag
14223 and then Chars (Old_C) /= Name_uParent
14225 Append_Elmt (Old_C, Comp_List);
14228 Next_Component (Old_C);
14232 Create_All_Components;
14235 -- If discriminants are not static, or if this is a multi-level type
14236 -- extension, we have to include all components of the parent type.
14238 Old_C := First_Component (Typ);
14239 while Present (Old_C) loop
14240 New_C := Create_Component (Old_C);
14244 Constrain_Component_Type
14245 (Old_C, Subt, Decl_Node, Typ, Constraints));
14246 Set_Is_Public (New_C, Is_Public (Subt));
14248 Next_Component (Old_C);
14253 end Create_Constrained_Components;
14255 ------------------------------------------
14256 -- Decimal_Fixed_Point_Type_Declaration --
14257 ------------------------------------------
14259 procedure Decimal_Fixed_Point_Type_Declaration
14263 Loc : constant Source_Ptr := Sloc (Def);
14264 Digs_Expr : constant Node_Id := Digits_Expression (Def);
14265 Delta_Expr : constant Node_Id := Delta_Expression (Def);
14266 Implicit_Base : Entity_Id;
14273 Check_SPARK_05_Restriction
14274 ("decimal fixed point type is not allowed", Def);
14275 Check_Restriction (No_Fixed_Point, Def);
14277 -- Create implicit base type
14280 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
14281 Set_Etype (Implicit_Base, Implicit_Base);
14283 -- Analyze and process delta expression
14285 Analyze_And_Resolve (Delta_Expr, Universal_Real);
14287 Check_Delta_Expression (Delta_Expr);
14288 Delta_Val := Expr_Value_R (Delta_Expr);
14290 -- Check delta is power of 10, and determine scale value from it
14296 Scale_Val := Uint_0;
14299 if Val < Ureal_1 then
14300 while Val < Ureal_1 loop
14301 Val := Val * Ureal_10;
14302 Scale_Val := Scale_Val + 1;
14305 if Scale_Val > 18 then
14306 Error_Msg_N ("scale exceeds maximum value of 18", Def);
14307 Scale_Val := UI_From_Int (+18);
14311 while Val > Ureal_1 loop
14312 Val := Val / Ureal_10;
14313 Scale_Val := Scale_Val - 1;
14316 if Scale_Val < -18 then
14317 Error_Msg_N ("scale is less than minimum value of -18", Def);
14318 Scale_Val := UI_From_Int (-18);
14322 if Val /= Ureal_1 then
14323 Error_Msg_N ("delta expression must be a power of 10", Def);
14324 Delta_Val := Ureal_10 ** (-Scale_Val);
14328 -- Set delta, scale and small (small = delta for decimal type)
14330 Set_Delta_Value (Implicit_Base, Delta_Val);
14331 Set_Scale_Value (Implicit_Base, Scale_Val);
14332 Set_Small_Value (Implicit_Base, Delta_Val);
14334 -- Analyze and process digits expression
14336 Analyze_And_Resolve (Digs_Expr, Any_Integer);
14337 Check_Digits_Expression (Digs_Expr);
14338 Digs_Val := Expr_Value (Digs_Expr);
14340 if Digs_Val > 18 then
14341 Digs_Val := UI_From_Int (+18);
14342 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
14345 Set_Digits_Value (Implicit_Base, Digs_Val);
14346 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
14348 -- Set range of base type from digits value for now. This will be
14349 -- expanded to represent the true underlying base range by Freeze.
14351 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
14353 -- Note: We leave size as zero for now, size will be set at freeze
14354 -- time. We have to do this for ordinary fixed-point, because the size
14355 -- depends on the specified small, and we might as well do the same for
14356 -- decimal fixed-point.
14358 pragma Assert (Esize (Implicit_Base) = Uint_0);
14360 -- If there are bounds given in the declaration use them as the
14361 -- bounds of the first named subtype.
14363 if Present (Real_Range_Specification (Def)) then
14365 RRS : constant Node_Id := Real_Range_Specification (Def);
14366 Low : constant Node_Id := Low_Bound (RRS);
14367 High : constant Node_Id := High_Bound (RRS);
14372 Analyze_And_Resolve (Low, Any_Real);
14373 Analyze_And_Resolve (High, Any_Real);
14374 Check_Real_Bound (Low);
14375 Check_Real_Bound (High);
14376 Low_Val := Expr_Value_R (Low);
14377 High_Val := Expr_Value_R (High);
14379 if Low_Val < (-Bound_Val) then
14381 ("range low bound too small for digits value", Low);
14382 Low_Val := -Bound_Val;
14385 if High_Val > Bound_Val then
14387 ("range high bound too large for digits value", High);
14388 High_Val := Bound_Val;
14391 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
14394 -- If no explicit range, use range that corresponds to given
14395 -- digits value. This will end up as the final range for the
14399 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
14402 -- Complete entity for first subtype. The inheritance of the rep item
14403 -- chain ensures that SPARK-related pragmas are not clobbered when the
14404 -- decimal fixed point type acts as a full view of a private type.
14406 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
14407 Set_Etype (T, Implicit_Base);
14408 Set_Size_Info (T, Implicit_Base);
14409 Inherit_Rep_Item_Chain (T, Implicit_Base);
14410 Set_Digits_Value (T, Digs_Val);
14411 Set_Delta_Value (T, Delta_Val);
14412 Set_Small_Value (T, Delta_Val);
14413 Set_Scale_Value (T, Scale_Val);
14414 Set_Is_Constrained (T);
14415 end Decimal_Fixed_Point_Type_Declaration;
14417 -----------------------------------
14418 -- Derive_Progenitor_Subprograms --
14419 -----------------------------------
14421 procedure Derive_Progenitor_Subprograms
14422 (Parent_Type : Entity_Id;
14423 Tagged_Type : Entity_Id)
14428 Iface_Elmt : Elmt_Id;
14429 Iface_Subp : Entity_Id;
14430 New_Subp : Entity_Id := Empty;
14431 Prim_Elmt : Elmt_Id;
14436 pragma Assert (Ada_Version >= Ada_2005
14437 and then Is_Record_Type (Tagged_Type)
14438 and then Is_Tagged_Type (Tagged_Type)
14439 and then Has_Interfaces (Tagged_Type));
14441 -- Step 1: Transfer to the full-view primitives associated with the
14442 -- partial-view that cover interface primitives. Conceptually this
14443 -- work should be done later by Process_Full_View; done here to
14444 -- simplify its implementation at later stages. It can be safely
14445 -- done here because interfaces must be visible in the partial and
14446 -- private view (RM 7.3(7.3/2)).
14448 -- Small optimization: This work is only required if the parent may
14449 -- have entities whose Alias attribute reference an interface primitive.
14450 -- Such a situation may occur if the parent is an abstract type and the
14451 -- primitive has not been yet overridden or if the parent is a generic
14452 -- formal type covering interfaces.
14454 -- If the tagged type is not abstract, it cannot have abstract
14455 -- primitives (the only entities in the list of primitives of
14456 -- non-abstract tagged types that can reference abstract primitives
14457 -- through its Alias attribute are the internal entities that have
14458 -- attribute Interface_Alias, and these entities are generated later
14459 -- by Add_Internal_Interface_Entities).
14461 if In_Private_Part (Current_Scope)
14462 and then (Is_Abstract_Type (Parent_Type)
14464 Is_Generic_Type (Parent_Type))
14466 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
14467 while Present (Elmt) loop
14468 Subp := Node (Elmt);
14470 -- At this stage it is not possible to have entities in the list
14471 -- of primitives that have attribute Interface_Alias.
14473 pragma Assert (No (Interface_Alias (Subp)));
14475 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
14477 if Is_Interface (Typ) then
14478 E := Find_Primitive_Covering_Interface
14479 (Tagged_Type => Tagged_Type,
14480 Iface_Prim => Subp);
14483 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
14485 Replace_Elmt (Elmt, E);
14486 Remove_Homonym (Subp);
14494 -- Step 2: Add primitives of progenitors that are not implemented by
14495 -- parents of Tagged_Type.
14497 if Present (Interfaces (Base_Type (Tagged_Type))) then
14498 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
14499 while Present (Iface_Elmt) loop
14500 Iface := Node (Iface_Elmt);
14502 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
14503 while Present (Prim_Elmt) loop
14504 Iface_Subp := Node (Prim_Elmt);
14506 -- Exclude derivation of predefined primitives except those
14507 -- that come from source, or are inherited from one that comes
14508 -- from source. Required to catch declarations of equality
14509 -- operators of interfaces. For example:
14511 -- type Iface is interface;
14512 -- function "=" (Left, Right : Iface) return Boolean;
14514 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
14515 or else Comes_From_Source (Ultimate_Alias (Iface_Subp))
14517 E := Find_Primitive_Covering_Interface
14518 (Tagged_Type => Tagged_Type,
14519 Iface_Prim => Iface_Subp);
14521 -- If not found we derive a new primitive leaving its alias
14522 -- attribute referencing the interface primitive.
14526 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14528 -- Ada 2012 (AI05-0197): If the covering primitive's name
14529 -- differs from the name of the interface primitive then it
14530 -- is a private primitive inherited from a parent type. In
14531 -- such case, given that Tagged_Type covers the interface,
14532 -- the inherited private primitive becomes visible. For such
14533 -- purpose we add a new entity that renames the inherited
14534 -- private primitive.
14536 elsif Chars (E) /= Chars (Iface_Subp) then
14537 pragma Assert (Has_Suffix (E, 'P'));
14539 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14540 Set_Alias (New_Subp, E);
14541 Set_Is_Abstract_Subprogram (New_Subp,
14542 Is_Abstract_Subprogram (E));
14544 -- Propagate to the full view interface entities associated
14545 -- with the partial view.
14547 elsif In_Private_Part (Current_Scope)
14548 and then Present (Alias (E))
14549 and then Alias (E) = Iface_Subp
14551 List_Containing (Parent (E)) /=
14552 Private_Declarations
14554 (Unit_Declaration_Node (Current_Scope)))
14556 Append_Elmt (E, Primitive_Operations (Tagged_Type));
14560 Next_Elmt (Prim_Elmt);
14563 Next_Elmt (Iface_Elmt);
14566 end Derive_Progenitor_Subprograms;
14568 -----------------------
14569 -- Derive_Subprogram --
14570 -----------------------
14572 procedure Derive_Subprogram
14573 (New_Subp : out Entity_Id;
14574 Parent_Subp : Entity_Id;
14575 Derived_Type : Entity_Id;
14576 Parent_Type : Entity_Id;
14577 Actual_Subp : Entity_Id := Empty)
14579 Formal : Entity_Id;
14580 -- Formal parameter of parent primitive operation
14582 Formal_Of_Actual : Entity_Id;
14583 -- Formal parameter of actual operation, when the derivation is to
14584 -- create a renaming for a primitive operation of an actual in an
14587 New_Formal : Entity_Id;
14588 -- Formal of inherited operation
14590 Visible_Subp : Entity_Id := Parent_Subp;
14592 function Is_Private_Overriding return Boolean;
14593 -- If Subp is a private overriding of a visible operation, the inherited
14594 -- operation derives from the overridden op (even though its body is the
14595 -- overriding one) and the inherited operation is visible now. See
14596 -- sem_disp to see the full details of the handling of the overridden
14597 -- subprogram, which is removed from the list of primitive operations of
14598 -- the type. The overridden subprogram is saved locally in Visible_Subp,
14599 -- and used to diagnose abstract operations that need overriding in the
14602 procedure Replace_Type (Id, New_Id : Entity_Id);
14603 -- When the type is an anonymous access type, create a new access type
14604 -- designating the derived type.
14606 procedure Set_Derived_Name;
14607 -- This procedure sets the appropriate Chars name for New_Subp. This
14608 -- is normally just a copy of the parent name. An exception arises for
14609 -- type support subprograms, where the name is changed to reflect the
14610 -- name of the derived type, e.g. if type foo is derived from type bar,
14611 -- then a procedure barDA is derived with a name fooDA.
14613 ---------------------------
14614 -- Is_Private_Overriding --
14615 ---------------------------
14617 function Is_Private_Overriding return Boolean is
14621 -- If the parent is not a dispatching operation there is no
14622 -- need to investigate overridings
14624 if not Is_Dispatching_Operation (Parent_Subp) then
14628 -- The visible operation that is overridden is a homonym of the
14629 -- parent subprogram. We scan the homonym chain to find the one
14630 -- whose alias is the subprogram we are deriving.
14632 Prev := Current_Entity (Parent_Subp);
14633 while Present (Prev) loop
14634 if Ekind (Prev) = Ekind (Parent_Subp)
14635 and then Alias (Prev) = Parent_Subp
14636 and then Scope (Parent_Subp) = Scope (Prev)
14637 and then not Is_Hidden (Prev)
14639 Visible_Subp := Prev;
14643 Prev := Homonym (Prev);
14647 end Is_Private_Overriding;
14653 procedure Replace_Type (Id, New_Id : Entity_Id) is
14654 Id_Type : constant Entity_Id := Etype (Id);
14655 Acc_Type : Entity_Id;
14656 Par : constant Node_Id := Parent (Derived_Type);
14659 -- When the type is an anonymous access type, create a new access
14660 -- type designating the derived type. This itype must be elaborated
14661 -- at the point of the derivation, not on subsequent calls that may
14662 -- be out of the proper scope for Gigi, so we insert a reference to
14663 -- it after the derivation.
14665 if Ekind (Id_Type) = E_Anonymous_Access_Type then
14667 Desig_Typ : Entity_Id := Designated_Type (Id_Type);
14670 if Ekind (Desig_Typ) = E_Record_Type_With_Private
14671 and then Present (Full_View (Desig_Typ))
14672 and then not Is_Private_Type (Parent_Type)
14674 Desig_Typ := Full_View (Desig_Typ);
14677 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
14679 -- Ada 2005 (AI-251): Handle also derivations of abstract
14680 -- interface primitives.
14682 or else (Is_Interface (Desig_Typ)
14683 and then not Is_Class_Wide_Type (Desig_Typ))
14685 Acc_Type := New_Copy (Id_Type);
14686 Set_Etype (Acc_Type, Acc_Type);
14687 Set_Scope (Acc_Type, New_Subp);
14689 -- Set size of anonymous access type. If we have an access
14690 -- to an unconstrained array, this is a fat pointer, so it
14691 -- is sizes at twice addtress size.
14693 if Is_Array_Type (Desig_Typ)
14694 and then not Is_Constrained (Desig_Typ)
14696 Init_Size (Acc_Type, 2 * System_Address_Size);
14698 -- Other cases use a thin pointer
14701 Init_Size (Acc_Type, System_Address_Size);
14704 -- Set remaining characterstics of anonymous access type
14706 Init_Alignment (Acc_Type);
14707 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
14709 Set_Etype (New_Id, Acc_Type);
14710 Set_Scope (New_Id, New_Subp);
14712 -- Create a reference to it
14714 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
14717 Set_Etype (New_Id, Id_Type);
14721 -- In Ada2012, a formal may have an incomplete type but the type
14722 -- derivation that inherits the primitive follows the full view.
14724 elsif Base_Type (Id_Type) = Base_Type (Parent_Type)
14726 (Ekind (Id_Type) = E_Record_Type_With_Private
14727 and then Present (Full_View (Id_Type))
14729 Base_Type (Full_View (Id_Type)) = Base_Type (Parent_Type))
14731 (Ada_Version >= Ada_2012
14732 and then Ekind (Id_Type) = E_Incomplete_Type
14733 and then Full_View (Id_Type) = Parent_Type)
14735 -- Constraint checks on formals are generated during expansion,
14736 -- based on the signature of the original subprogram. The bounds
14737 -- of the derived type are not relevant, and thus we can use
14738 -- the base type for the formals. However, the return type may be
14739 -- used in a context that requires that the proper static bounds
14740 -- be used (a case statement, for example) and for those cases
14741 -- we must use the derived type (first subtype), not its base.
14743 -- If the derived_type_definition has no constraints, we know that
14744 -- the derived type has the same constraints as the first subtype
14745 -- of the parent, and we can also use it rather than its base,
14746 -- which can lead to more efficient code.
14748 if Etype (Id) = Parent_Type then
14749 if Is_Scalar_Type (Parent_Type)
14751 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
14753 Set_Etype (New_Id, Derived_Type);
14755 elsif Nkind (Par) = N_Full_Type_Declaration
14757 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
14760 (Subtype_Indication (Type_Definition (Par)))
14762 Set_Etype (New_Id, Derived_Type);
14765 Set_Etype (New_Id, Base_Type (Derived_Type));
14769 Set_Etype (New_Id, Base_Type (Derived_Type));
14773 Set_Etype (New_Id, Etype (Id));
14777 ----------------------
14778 -- Set_Derived_Name --
14779 ----------------------
14781 procedure Set_Derived_Name is
14782 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
14784 if Nm = TSS_Null then
14785 Set_Chars (New_Subp, Chars (Parent_Subp));
14787 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
14789 end Set_Derived_Name;
14791 -- Start of processing for Derive_Subprogram
14794 New_Subp := New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
14795 Set_Ekind (New_Subp, Ekind (Parent_Subp));
14797 -- Check whether the inherited subprogram is a private operation that
14798 -- should be inherited but not yet made visible. Such subprograms can
14799 -- become visible at a later point (e.g., the private part of a public
14800 -- child unit) via Declare_Inherited_Private_Subprograms. If the
14801 -- following predicate is true, then this is not such a private
14802 -- operation and the subprogram simply inherits the name of the parent
14803 -- subprogram. Note the special check for the names of controlled
14804 -- operations, which are currently exempted from being inherited with
14805 -- a hidden name because they must be findable for generation of
14806 -- implicit run-time calls.
14808 if not Is_Hidden (Parent_Subp)
14809 or else Is_Internal (Parent_Subp)
14810 or else Is_Private_Overriding
14811 or else Is_Internal_Name (Chars (Parent_Subp))
14812 or else (Is_Controlled (Parent_Type)
14813 and then Nam_In (Chars (Parent_Subp), Name_Adjust,
14819 -- An inherited dispatching equality will be overridden by an internally
14820 -- generated one, or by an explicit one, so preserve its name and thus
14821 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
14822 -- private operation it may become invisible if the full view has
14823 -- progenitors, and the dispatch table will be malformed.
14824 -- We check that the type is limited to handle the anomalous declaration
14825 -- of Limited_Controlled, which is derived from a non-limited type, and
14826 -- which is handled specially elsewhere as well.
14828 elsif Chars (Parent_Subp) = Name_Op_Eq
14829 and then Is_Dispatching_Operation (Parent_Subp)
14830 and then Etype (Parent_Subp) = Standard_Boolean
14831 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
14833 Etype (First_Formal (Parent_Subp)) =
14834 Etype (Next_Formal (First_Formal (Parent_Subp)))
14838 -- If parent is hidden, this can be a regular derivation if the
14839 -- parent is immediately visible in a non-instantiating context,
14840 -- or if we are in the private part of an instance. This test
14841 -- should still be refined ???
14843 -- The test for In_Instance_Not_Visible avoids inheriting the derived
14844 -- operation as a non-visible operation in cases where the parent
14845 -- subprogram might not be visible now, but was visible within the
14846 -- original generic, so it would be wrong to make the inherited
14847 -- subprogram non-visible now. (Not clear if this test is fully
14848 -- correct; are there any cases where we should declare the inherited
14849 -- operation as not visible to avoid it being overridden, e.g., when
14850 -- the parent type is a generic actual with private primitives ???)
14852 -- (they should be treated the same as other private inherited
14853 -- subprograms, but it's not clear how to do this cleanly). ???
14855 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
14856 and then Is_Immediately_Visible (Parent_Subp)
14857 and then not In_Instance)
14858 or else In_Instance_Not_Visible
14862 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
14863 -- overrides an interface primitive because interface primitives
14864 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
14866 elsif Ada_Version >= Ada_2005
14867 and then Is_Dispatching_Operation (Parent_Subp)
14868 and then Covers_Some_Interface (Parent_Subp)
14872 -- Otherwise, the type is inheriting a private operation, so enter it
14873 -- with a special name so it can't be overridden.
14876 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
14879 Set_Parent (New_Subp, Parent (Derived_Type));
14881 if Present (Actual_Subp) then
14882 Replace_Type (Actual_Subp, New_Subp);
14884 Replace_Type (Parent_Subp, New_Subp);
14887 Conditional_Delay (New_Subp, Parent_Subp);
14889 -- If we are creating a renaming for a primitive operation of an
14890 -- actual of a generic derived type, we must examine the signature
14891 -- of the actual primitive, not that of the generic formal, which for
14892 -- example may be an interface. However the name and initial value
14893 -- of the inherited operation are those of the formal primitive.
14895 Formal := First_Formal (Parent_Subp);
14897 if Present (Actual_Subp) then
14898 Formal_Of_Actual := First_Formal (Actual_Subp);
14900 Formal_Of_Actual := Empty;
14903 while Present (Formal) loop
14904 New_Formal := New_Copy (Formal);
14906 -- Normally we do not go copying parents, but in the case of
14907 -- formals, we need to link up to the declaration (which is the
14908 -- parameter specification), and it is fine to link up to the
14909 -- original formal's parameter specification in this case.
14911 Set_Parent (New_Formal, Parent (Formal));
14912 Append_Entity (New_Formal, New_Subp);
14914 if Present (Formal_Of_Actual) then
14915 Replace_Type (Formal_Of_Actual, New_Formal);
14916 Next_Formal (Formal_Of_Actual);
14918 Replace_Type (Formal, New_Formal);
14921 Next_Formal (Formal);
14924 -- If this derivation corresponds to a tagged generic actual, then
14925 -- primitive operations rename those of the actual. Otherwise the
14926 -- primitive operations rename those of the parent type, If the parent
14927 -- renames an intrinsic operator, so does the new subprogram. We except
14928 -- concatenation, which is always properly typed, and does not get
14929 -- expanded as other intrinsic operations.
14931 if No (Actual_Subp) then
14932 if Is_Intrinsic_Subprogram (Parent_Subp) then
14933 Set_Is_Intrinsic_Subprogram (New_Subp);
14935 if Present (Alias (Parent_Subp))
14936 and then Chars (Parent_Subp) /= Name_Op_Concat
14938 Set_Alias (New_Subp, Alias (Parent_Subp));
14940 Set_Alias (New_Subp, Parent_Subp);
14944 Set_Alias (New_Subp, Parent_Subp);
14948 Set_Alias (New_Subp, Actual_Subp);
14951 -- Inherit the "ghostness" from the parent subprogram
14953 if Is_Ghost_Entity (Alias (New_Subp)) then
14954 Set_Is_Ghost_Entity (New_Subp);
14957 -- Derived subprograms of a tagged type must inherit the convention
14958 -- of the parent subprogram (a requirement of AI-117). Derived
14959 -- subprograms of untagged types simply get convention Ada by default.
14961 -- If the derived type is a tagged generic formal type with unknown
14962 -- discriminants, its convention is intrinsic (RM 6.3.1 (8)).
14964 -- However, if the type is derived from a generic formal, the further
14965 -- inherited subprogram has the convention of the non-generic ancestor.
14966 -- Otherwise there would be no way to override the operation.
14967 -- (This is subject to forthcoming ARG discussions).
14969 if Is_Tagged_Type (Derived_Type) then
14970 if Is_Generic_Type (Derived_Type)
14971 and then Has_Unknown_Discriminants (Derived_Type)
14973 Set_Convention (New_Subp, Convention_Intrinsic);
14976 if Is_Generic_Type (Parent_Type)
14977 and then Has_Unknown_Discriminants (Parent_Type)
14979 Set_Convention (New_Subp, Convention (Alias (Parent_Subp)));
14981 Set_Convention (New_Subp, Convention (Parent_Subp));
14986 -- Predefined controlled operations retain their name even if the parent
14987 -- is hidden (see above), but they are not primitive operations if the
14988 -- ancestor is not visible, for example if the parent is a private
14989 -- extension completed with a controlled extension. Note that a full
14990 -- type that is controlled can break privacy: the flag Is_Controlled is
14991 -- set on both views of the type.
14993 if Is_Controlled (Parent_Type)
14994 and then Nam_In (Chars (Parent_Subp), Name_Initialize,
14997 and then Is_Hidden (Parent_Subp)
14998 and then not Is_Visibly_Controlled (Parent_Type)
15000 Set_Is_Hidden (New_Subp);
15003 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
15004 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
15006 if Ekind (Parent_Subp) = E_Procedure then
15007 Set_Is_Valued_Procedure
15008 (New_Subp, Is_Valued_Procedure (Parent_Subp));
15010 Set_Has_Controlling_Result
15011 (New_Subp, Has_Controlling_Result (Parent_Subp));
15014 -- No_Return must be inherited properly. If this is overridden in the
15015 -- case of a dispatching operation, then a check is made in Sem_Disp
15016 -- that the overriding operation is also No_Return (no such check is
15017 -- required for the case of non-dispatching operation.
15019 Set_No_Return (New_Subp, No_Return (Parent_Subp));
15021 -- A derived function with a controlling result is abstract. If the
15022 -- Derived_Type is a nonabstract formal generic derived type, then
15023 -- inherited operations are not abstract: the required check is done at
15024 -- instantiation time. If the derivation is for a generic actual, the
15025 -- function is not abstract unless the actual is.
15027 if Is_Generic_Type (Derived_Type)
15028 and then not Is_Abstract_Type (Derived_Type)
15032 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
15033 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
15035 -- A subprogram subject to pragma Extensions_Visible with value False
15036 -- requires overriding if the subprogram has at least one controlling
15037 -- OUT parameter (SPARK RM 6.1.7(6)).
15039 elsif Ada_Version >= Ada_2005
15040 and then (Is_Abstract_Subprogram (Alias (New_Subp))
15041 or else (Is_Tagged_Type (Derived_Type)
15042 and then Etype (New_Subp) = Derived_Type
15043 and then not Is_Null_Extension (Derived_Type))
15044 or else (Is_Tagged_Type (Derived_Type)
15045 and then Ekind (Etype (New_Subp)) =
15046 E_Anonymous_Access_Type
15047 and then Designated_Type (Etype (New_Subp)) =
15049 and then not Is_Null_Extension (Derived_Type))
15050 or else (Comes_From_Source (Alias (New_Subp))
15051 and then Is_EVF_Procedure (Alias (New_Subp))))
15052 and then No (Actual_Subp)
15054 if not Is_Tagged_Type (Derived_Type)
15055 or else Is_Abstract_Type (Derived_Type)
15056 or else Is_Abstract_Subprogram (Alias (New_Subp))
15058 Set_Is_Abstract_Subprogram (New_Subp);
15060 Set_Requires_Overriding (New_Subp);
15063 elsif Ada_Version < Ada_2005
15064 and then (Is_Abstract_Subprogram (Alias (New_Subp))
15065 or else (Is_Tagged_Type (Derived_Type)
15066 and then Etype (New_Subp) = Derived_Type
15067 and then No (Actual_Subp)))
15069 Set_Is_Abstract_Subprogram (New_Subp);
15071 -- AI05-0097 : an inherited operation that dispatches on result is
15072 -- abstract if the derived type is abstract, even if the parent type
15073 -- is concrete and the derived type is a null extension.
15075 elsif Has_Controlling_Result (Alias (New_Subp))
15076 and then Is_Abstract_Type (Etype (New_Subp))
15078 Set_Is_Abstract_Subprogram (New_Subp);
15080 -- Finally, if the parent type is abstract we must verify that all
15081 -- inherited operations are either non-abstract or overridden, or that
15082 -- the derived type itself is abstract (this check is performed at the
15083 -- end of a package declaration, in Check_Abstract_Overriding). A
15084 -- private overriding in the parent type will not be visible in the
15085 -- derivation if we are not in an inner package or in a child unit of
15086 -- the parent type, in which case the abstractness of the inherited
15087 -- operation is carried to the new subprogram.
15089 elsif Is_Abstract_Type (Parent_Type)
15090 and then not In_Open_Scopes (Scope (Parent_Type))
15091 and then Is_Private_Overriding
15092 and then Is_Abstract_Subprogram (Visible_Subp)
15094 if No (Actual_Subp) then
15095 Set_Alias (New_Subp, Visible_Subp);
15096 Set_Is_Abstract_Subprogram (New_Subp, True);
15099 -- If this is a derivation for an instance of a formal derived
15100 -- type, abstractness comes from the primitive operation of the
15101 -- actual, not from the operation inherited from the ancestor.
15103 Set_Is_Abstract_Subprogram
15104 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
15108 New_Overloaded_Entity (New_Subp, Derived_Type);
15110 -- Check for case of a derived subprogram for the instantiation of a
15111 -- formal derived tagged type, if so mark the subprogram as dispatching
15112 -- and inherit the dispatching attributes of the actual subprogram. The
15113 -- derived subprogram is effectively renaming of the actual subprogram,
15114 -- so it needs to have the same attributes as the actual.
15116 if Present (Actual_Subp)
15117 and then Is_Dispatching_Operation (Actual_Subp)
15119 Set_Is_Dispatching_Operation (New_Subp);
15121 if Present (DTC_Entity (Actual_Subp)) then
15122 Set_DTC_Entity (New_Subp, DTC_Entity (Actual_Subp));
15123 Set_DT_Position_Value (New_Subp, DT_Position (Actual_Subp));
15127 -- Indicate that a derived subprogram does not require a body and that
15128 -- it does not require processing of default expressions.
15130 Set_Has_Completion (New_Subp);
15131 Set_Default_Expressions_Processed (New_Subp);
15133 if Ekind (New_Subp) = E_Function then
15134 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
15136 end Derive_Subprogram;
15138 ------------------------
15139 -- Derive_Subprograms --
15140 ------------------------
15142 procedure Derive_Subprograms
15143 (Parent_Type : Entity_Id;
15144 Derived_Type : Entity_Id;
15145 Generic_Actual : Entity_Id := Empty)
15147 Op_List : constant Elist_Id :=
15148 Collect_Primitive_Operations (Parent_Type);
15150 function Check_Derived_Type return Boolean;
15151 -- Check that all the entities derived from Parent_Type are found in
15152 -- the list of primitives of Derived_Type exactly in the same order.
15154 procedure Derive_Interface_Subprogram
15155 (New_Subp : out Entity_Id;
15157 Actual_Subp : Entity_Id);
15158 -- Derive New_Subp from the ultimate alias of the parent subprogram Subp
15159 -- (which is an interface primitive). If Generic_Actual is present then
15160 -- Actual_Subp is the actual subprogram corresponding with the generic
15161 -- subprogram Subp.
15163 function Check_Derived_Type return Boolean is
15167 New_Subp : Entity_Id;
15172 -- Traverse list of entities in the current scope searching for
15173 -- an incomplete type whose full-view is derived type
15175 E := First_Entity (Scope (Derived_Type));
15176 while Present (E) and then E /= Derived_Type loop
15177 if Ekind (E) = E_Incomplete_Type
15178 and then Present (Full_View (E))
15179 and then Full_View (E) = Derived_Type
15181 -- Disable this test if Derived_Type completes an incomplete
15182 -- type because in such case more primitives can be added
15183 -- later to the list of primitives of Derived_Type by routine
15184 -- Process_Incomplete_Dependents
15189 E := Next_Entity (E);
15192 List := Collect_Primitive_Operations (Derived_Type);
15193 Elmt := First_Elmt (List);
15195 Op_Elmt := First_Elmt (Op_List);
15196 while Present (Op_Elmt) loop
15197 Subp := Node (Op_Elmt);
15198 New_Subp := Node (Elmt);
15200 -- At this early stage Derived_Type has no entities with attribute
15201 -- Interface_Alias. In addition, such primitives are always
15202 -- located at the end of the list of primitives of Parent_Type.
15203 -- Therefore, if found we can safely stop processing pending
15206 exit when Present (Interface_Alias (Subp));
15208 -- Handle hidden entities
15210 if not Is_Predefined_Dispatching_Operation (Subp)
15211 and then Is_Hidden (Subp)
15213 if Present (New_Subp)
15214 and then Primitive_Names_Match (Subp, New_Subp)
15220 if not Present (New_Subp)
15221 or else Ekind (Subp) /= Ekind (New_Subp)
15222 or else not Primitive_Names_Match (Subp, New_Subp)
15230 Next_Elmt (Op_Elmt);
15234 end Check_Derived_Type;
15236 ---------------------------------
15237 -- Derive_Interface_Subprogram --
15238 ---------------------------------
15240 procedure Derive_Interface_Subprogram
15241 (New_Subp : out Entity_Id;
15243 Actual_Subp : Entity_Id)
15245 Iface_Subp : constant Entity_Id := Ultimate_Alias (Subp);
15246 Iface_Type : constant Entity_Id := Find_Dispatching_Type (Iface_Subp);
15249 pragma Assert (Is_Interface (Iface_Type));
15252 (New_Subp => New_Subp,
15253 Parent_Subp => Iface_Subp,
15254 Derived_Type => Derived_Type,
15255 Parent_Type => Iface_Type,
15256 Actual_Subp => Actual_Subp);
15258 -- Given that this new interface entity corresponds with a primitive
15259 -- of the parent that was not overridden we must leave it associated
15260 -- with its parent primitive to ensure that it will share the same
15261 -- dispatch table slot when overridden. We must set the Alias to Subp
15262 -- (instead of Iface_Subp), and we must fix Is_Abstract_Subprogram
15263 -- (in case we inherited Subp from Iface_Type via a nonabstract
15264 -- generic formal type).
15266 if No (Actual_Subp) then
15267 Set_Alias (New_Subp, Subp);
15270 T : Entity_Id := Find_Dispatching_Type (Subp);
15272 while Etype (T) /= T loop
15273 if Is_Generic_Type (T) and then not Is_Abstract_Type (T) then
15274 Set_Is_Abstract_Subprogram (New_Subp, False);
15282 -- For instantiations this is not needed since the previous call to
15283 -- Derive_Subprogram leaves the entity well decorated.
15286 pragma Assert (Alias (New_Subp) = Actual_Subp);
15289 end Derive_Interface_Subprogram;
15293 Alias_Subp : Entity_Id;
15294 Act_List : Elist_Id;
15295 Act_Elmt : Elmt_Id;
15296 Act_Subp : Entity_Id := Empty;
15298 Need_Search : Boolean := False;
15299 New_Subp : Entity_Id := Empty;
15300 Parent_Base : Entity_Id;
15303 -- Start of processing for Derive_Subprograms
15306 if Ekind (Parent_Type) = E_Record_Type_With_Private
15307 and then Has_Discriminants (Parent_Type)
15308 and then Present (Full_View (Parent_Type))
15310 Parent_Base := Full_View (Parent_Type);
15312 Parent_Base := Parent_Type;
15315 if Present (Generic_Actual) then
15316 Act_List := Collect_Primitive_Operations (Generic_Actual);
15317 Act_Elmt := First_Elmt (Act_List);
15319 Act_List := No_Elist;
15320 Act_Elmt := No_Elmt;
15323 -- Derive primitives inherited from the parent. Note that if the generic
15324 -- actual is present, this is not really a type derivation, it is a
15325 -- completion within an instance.
15327 -- Case 1: Derived_Type does not implement interfaces
15329 if not Is_Tagged_Type (Derived_Type)
15330 or else (not Has_Interfaces (Derived_Type)
15331 and then not (Present (Generic_Actual)
15332 and then Has_Interfaces (Generic_Actual)))
15334 Elmt := First_Elmt (Op_List);
15335 while Present (Elmt) loop
15336 Subp := Node (Elmt);
15338 -- Literals are derived earlier in the process of building the
15339 -- derived type, and are skipped here.
15341 if Ekind (Subp) = E_Enumeration_Literal then
15344 -- The actual is a direct descendant and the common primitive
15345 -- operations appear in the same order.
15347 -- If the generic parent type is present, the derived type is an
15348 -- instance of a formal derived type, and within the instance its
15349 -- operations are those of the actual. We derive from the formal
15350 -- type but make the inherited operations aliases of the
15351 -- corresponding operations of the actual.
15354 pragma Assert (No (Node (Act_Elmt))
15355 or else (Primitive_Names_Match (Subp, Node (Act_Elmt))
15358 (Subp, Node (Act_Elmt),
15359 Skip_Controlling_Formals => True)));
15362 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
15364 if Present (Act_Elmt) then
15365 Next_Elmt (Act_Elmt);
15372 -- Case 2: Derived_Type implements interfaces
15375 -- If the parent type has no predefined primitives we remove
15376 -- predefined primitives from the list of primitives of generic
15377 -- actual to simplify the complexity of this algorithm.
15379 if Present (Generic_Actual) then
15381 Has_Predefined_Primitives : Boolean := False;
15384 -- Check if the parent type has predefined primitives
15386 Elmt := First_Elmt (Op_List);
15387 while Present (Elmt) loop
15388 Subp := Node (Elmt);
15390 if Is_Predefined_Dispatching_Operation (Subp)
15391 and then not Comes_From_Source (Ultimate_Alias (Subp))
15393 Has_Predefined_Primitives := True;
15400 -- Remove predefined primitives of Generic_Actual. We must use
15401 -- an auxiliary list because in case of tagged types the value
15402 -- returned by Collect_Primitive_Operations is the value stored
15403 -- in its Primitive_Operations attribute (and we don't want to
15404 -- modify its current contents).
15406 if not Has_Predefined_Primitives then
15408 Aux_List : constant Elist_Id := New_Elmt_List;
15411 Elmt := First_Elmt (Act_List);
15412 while Present (Elmt) loop
15413 Subp := Node (Elmt);
15415 if not Is_Predefined_Dispatching_Operation (Subp)
15416 or else Comes_From_Source (Subp)
15418 Append_Elmt (Subp, Aux_List);
15424 Act_List := Aux_List;
15428 Act_Elmt := First_Elmt (Act_List);
15429 Act_Subp := Node (Act_Elmt);
15433 -- Stage 1: If the generic actual is not present we derive the
15434 -- primitives inherited from the parent type. If the generic parent
15435 -- type is present, the derived type is an instance of a formal
15436 -- derived type, and within the instance its operations are those of
15437 -- the actual. We derive from the formal type but make the inherited
15438 -- operations aliases of the corresponding operations of the actual.
15440 Elmt := First_Elmt (Op_List);
15441 while Present (Elmt) loop
15442 Subp := Node (Elmt);
15443 Alias_Subp := Ultimate_Alias (Subp);
15445 -- Do not derive internal entities of the parent that link
15446 -- interface primitives with their covering primitive. These
15447 -- entities will be added to this type when frozen.
15449 if Present (Interface_Alias (Subp)) then
15453 -- If the generic actual is present find the corresponding
15454 -- operation in the generic actual. If the parent type is a
15455 -- direct ancestor of the derived type then, even if it is an
15456 -- interface, the operations are inherited from the primary
15457 -- dispatch table and are in the proper order. If we detect here
15458 -- that primitives are not in the same order we traverse the list
15459 -- of primitive operations of the actual to find the one that
15460 -- implements the interface primitive.
15464 (Present (Generic_Actual)
15465 and then Present (Act_Subp)
15467 (Primitive_Names_Match (Subp, Act_Subp)
15469 Type_Conformant (Subp, Act_Subp,
15470 Skip_Controlling_Formals => True)))
15472 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual,
15473 Use_Full_View => True));
15475 -- Remember that we need searching for all pending primitives
15477 Need_Search := True;
15479 -- Handle entities associated with interface primitives
15481 if Present (Alias_Subp)
15482 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
15483 and then not Is_Predefined_Dispatching_Operation (Subp)
15485 -- Search for the primitive in the homonym chain
15488 Find_Primitive_Covering_Interface
15489 (Tagged_Type => Generic_Actual,
15490 Iface_Prim => Alias_Subp);
15492 -- Previous search may not locate primitives covering
15493 -- interfaces defined in generics units or instantiations.
15494 -- (it fails if the covering primitive has formals whose
15495 -- type is also defined in generics or instantiations).
15496 -- In such case we search in the list of primitives of the
15497 -- generic actual for the internal entity that links the
15498 -- interface primitive and the covering primitive.
15501 and then Is_Generic_Type (Parent_Type)
15503 -- This code has been designed to handle only generic
15504 -- formals that implement interfaces that are defined
15505 -- in a generic unit or instantiation. If this code is
15506 -- needed for other cases we must review it because
15507 -- (given that it relies on Original_Location to locate
15508 -- the primitive of Generic_Actual that covers the
15509 -- interface) it could leave linked through attribute
15510 -- Alias entities of unrelated instantiations).
15514 (Scope (Find_Dispatching_Type (Alias_Subp)))
15516 Instantiation_Depth
15517 (Sloc (Find_Dispatching_Type (Alias_Subp))) > 0);
15520 Iface_Prim_Loc : constant Source_Ptr :=
15521 Original_Location (Sloc (Alias_Subp));
15528 First_Elmt (Primitive_Operations (Generic_Actual));
15530 Search : while Present (Elmt) loop
15531 Prim := Node (Elmt);
15533 if Present (Interface_Alias (Prim))
15534 and then Original_Location
15535 (Sloc (Interface_Alias (Prim))) =
15538 Act_Subp := Alias (Prim);
15547 pragma Assert (Present (Act_Subp)
15548 or else Is_Abstract_Type (Generic_Actual)
15549 or else Serious_Errors_Detected > 0);
15551 -- Handle predefined primitives plus the rest of user-defined
15555 Act_Elmt := First_Elmt (Act_List);
15556 while Present (Act_Elmt) loop
15557 Act_Subp := Node (Act_Elmt);
15559 exit when Primitive_Names_Match (Subp, Act_Subp)
15560 and then Type_Conformant
15562 Skip_Controlling_Formals => True)
15563 and then No (Interface_Alias (Act_Subp));
15565 Next_Elmt (Act_Elmt);
15568 if No (Act_Elmt) then
15574 -- Case 1: If the parent is a limited interface then it has the
15575 -- predefined primitives of synchronized interfaces. However, the
15576 -- actual type may be a non-limited type and hence it does not
15577 -- have such primitives.
15579 if Present (Generic_Actual)
15580 and then not Present (Act_Subp)
15581 and then Is_Limited_Interface (Parent_Base)
15582 and then Is_Predefined_Interface_Primitive (Subp)
15586 -- Case 2: Inherit entities associated with interfaces that were
15587 -- not covered by the parent type. We exclude here null interface
15588 -- primitives because they do not need special management.
15590 -- We also exclude interface operations that are renamings. If the
15591 -- subprogram is an explicit renaming of an interface primitive,
15592 -- it is a regular primitive operation, and the presence of its
15593 -- alias is not relevant: it has to be derived like any other
15596 elsif Present (Alias (Subp))
15597 and then Nkind (Unit_Declaration_Node (Subp)) /=
15598 N_Subprogram_Renaming_Declaration
15599 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
15601 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
15602 and then Null_Present (Parent (Alias_Subp)))
15604 -- If this is an abstract private type then we transfer the
15605 -- derivation of the interface primitive from the partial view
15606 -- to the full view. This is safe because all the interfaces
15607 -- must be visible in the partial view. Done to avoid adding
15608 -- a new interface derivation to the private part of the
15609 -- enclosing package; otherwise this new derivation would be
15610 -- decorated as hidden when the analysis of the enclosing
15611 -- package completes.
15613 if Is_Abstract_Type (Derived_Type)
15614 and then In_Private_Part (Current_Scope)
15615 and then Has_Private_Declaration (Derived_Type)
15618 Partial_View : Entity_Id;
15623 Partial_View := First_Entity (Current_Scope);
15625 exit when No (Partial_View)
15626 or else (Has_Private_Declaration (Partial_View)
15628 Full_View (Partial_View) = Derived_Type);
15630 Next_Entity (Partial_View);
15633 -- If the partial view was not found then the source code
15634 -- has errors and the derivation is not needed.
15636 if Present (Partial_View) then
15638 First_Elmt (Primitive_Operations (Partial_View));
15639 while Present (Elmt) loop
15640 Ent := Node (Elmt);
15642 if Present (Alias (Ent))
15643 and then Ultimate_Alias (Ent) = Alias (Subp)
15646 (Ent, Primitive_Operations (Derived_Type));
15653 -- If the interface primitive was not found in the
15654 -- partial view then this interface primitive was
15655 -- overridden. We add a derivation to activate in
15656 -- Derive_Progenitor_Subprograms the machinery to
15660 Derive_Interface_Subprogram
15661 (New_Subp => New_Subp,
15663 Actual_Subp => Act_Subp);
15668 Derive_Interface_Subprogram
15669 (New_Subp => New_Subp,
15671 Actual_Subp => Act_Subp);
15674 -- Case 3: Common derivation
15678 (New_Subp => New_Subp,
15679 Parent_Subp => Subp,
15680 Derived_Type => Derived_Type,
15681 Parent_Type => Parent_Base,
15682 Actual_Subp => Act_Subp);
15685 -- No need to update Act_Elm if we must search for the
15686 -- corresponding operation in the generic actual
15689 and then Present (Act_Elmt)
15691 Next_Elmt (Act_Elmt);
15692 Act_Subp := Node (Act_Elmt);
15699 -- Inherit additional operations from progenitors. If the derived
15700 -- type is a generic actual, there are not new primitive operations
15701 -- for the type because it has those of the actual, and therefore
15702 -- nothing needs to be done. The renamings generated above are not
15703 -- primitive operations, and their purpose is simply to make the
15704 -- proper operations visible within an instantiation.
15706 if No (Generic_Actual) then
15707 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
15711 -- Final check: Direct descendants must have their primitives in the
15712 -- same order. We exclude from this test untagged types and instances
15713 -- of formal derived types. We skip this test if we have already
15714 -- reported serious errors in the sources.
15716 pragma Assert (not Is_Tagged_Type (Derived_Type)
15717 or else Present (Generic_Actual)
15718 or else Serious_Errors_Detected > 0
15719 or else Check_Derived_Type);
15720 end Derive_Subprograms;
15722 --------------------------------
15723 -- Derived_Standard_Character --
15724 --------------------------------
15726 procedure Derived_Standard_Character
15728 Parent_Type : Entity_Id;
15729 Derived_Type : Entity_Id)
15731 Loc : constant Source_Ptr := Sloc (N);
15732 Def : constant Node_Id := Type_Definition (N);
15733 Indic : constant Node_Id := Subtype_Indication (Def);
15734 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
15735 Implicit_Base : constant Entity_Id :=
15737 (E_Enumeration_Type, N, Derived_Type, 'B');
15743 Discard_Node (Process_Subtype (Indic, N));
15745 Set_Etype (Implicit_Base, Parent_Base);
15746 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
15747 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
15749 Set_Is_Character_Type (Implicit_Base, True);
15750 Set_Has_Delayed_Freeze (Implicit_Base);
15752 -- The bounds of the implicit base are the bounds of the parent base.
15753 -- Note that their type is the parent base.
15755 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
15756 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
15758 Set_Scalar_Range (Implicit_Base,
15761 High_Bound => Hi));
15763 Conditional_Delay (Derived_Type, Parent_Type);
15765 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
15766 Set_Etype (Derived_Type, Implicit_Base);
15767 Set_Size_Info (Derived_Type, Parent_Type);
15769 if Unknown_RM_Size (Derived_Type) then
15770 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
15773 Set_Is_Character_Type (Derived_Type, True);
15775 if Nkind (Indic) /= N_Subtype_Indication then
15777 -- If no explicit constraint, the bounds are those
15778 -- of the parent type.
15780 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
15781 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
15782 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
15785 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
15787 -- Because the implicit base is used in the conversion of the bounds, we
15788 -- have to freeze it now. This is similar to what is done for numeric
15789 -- types, and it equally suspicious, but otherwise a non-static bound
15790 -- will have a reference to an unfrozen type, which is rejected by Gigi
15791 -- (???). This requires specific care for definition of stream
15792 -- attributes. For details, see comments at the end of
15793 -- Build_Derived_Numeric_Type.
15795 Freeze_Before (N, Implicit_Base);
15796 end Derived_Standard_Character;
15798 ------------------------------
15799 -- Derived_Type_Declaration --
15800 ------------------------------
15802 procedure Derived_Type_Declaration
15805 Is_Completion : Boolean)
15807 Parent_Type : Entity_Id;
15809 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
15810 -- Check whether the parent type is a generic formal, or derives
15811 -- directly or indirectly from one.
15813 ------------------------
15814 -- Comes_From_Generic --
15815 ------------------------
15817 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
15819 if Is_Generic_Type (Typ) then
15822 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
15825 elsif Is_Private_Type (Typ)
15826 and then Present (Full_View (Typ))
15827 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
15831 elsif Is_Generic_Actual_Type (Typ) then
15837 end Comes_From_Generic;
15841 Def : constant Node_Id := Type_Definition (N);
15842 Iface_Def : Node_Id;
15843 Indic : constant Node_Id := Subtype_Indication (Def);
15844 Extension : constant Node_Id := Record_Extension_Part (Def);
15845 Parent_Node : Node_Id;
15848 -- Start of processing for Derived_Type_Declaration
15851 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
15853 -- Ada 2005 (AI-251): In case of interface derivation check that the
15854 -- parent is also an interface.
15856 if Interface_Present (Def) then
15857 Check_SPARK_05_Restriction ("interface is not allowed", Def);
15859 if not Is_Interface (Parent_Type) then
15860 Diagnose_Interface (Indic, Parent_Type);
15863 Parent_Node := Parent (Base_Type (Parent_Type));
15864 Iface_Def := Type_Definition (Parent_Node);
15866 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
15867 -- other limited interfaces.
15869 if Limited_Present (Def) then
15870 if Limited_Present (Iface_Def) then
15873 elsif Protected_Present (Iface_Def) then
15875 ("descendant of & must be declared as a protected "
15876 & "interface", N, Parent_Type);
15878 elsif Synchronized_Present (Iface_Def) then
15880 ("descendant of & must be declared as a synchronized "
15881 & "interface", N, Parent_Type);
15883 elsif Task_Present (Iface_Def) then
15885 ("descendant of & must be declared as a task interface",
15890 ("(Ada 2005) limited interface cannot inherit from "
15891 & "non-limited interface", Indic);
15894 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
15895 -- from non-limited or limited interfaces.
15897 elsif not Protected_Present (Def)
15898 and then not Synchronized_Present (Def)
15899 and then not Task_Present (Def)
15901 if Limited_Present (Iface_Def) then
15904 elsif Protected_Present (Iface_Def) then
15906 ("descendant of & must be declared as a protected "
15907 & "interface", N, Parent_Type);
15909 elsif Synchronized_Present (Iface_Def) then
15911 ("descendant of & must be declared as a synchronized "
15912 & "interface", N, Parent_Type);
15914 elsif Task_Present (Iface_Def) then
15916 ("descendant of & must be declared as a task interface",
15925 if Is_Tagged_Type (Parent_Type)
15926 and then Is_Concurrent_Type (Parent_Type)
15927 and then not Is_Interface (Parent_Type)
15930 ("parent type of a record extension cannot be a synchronized "
15931 & "tagged type (RM 3.9.1 (3/1))", N);
15932 Set_Etype (T, Any_Type);
15936 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
15939 if Is_Tagged_Type (Parent_Type)
15940 and then Is_Non_Empty_List (Interface_List (Def))
15947 Intf := First (Interface_List (Def));
15948 while Present (Intf) loop
15949 T := Find_Type_Of_Subtype_Indic (Intf);
15951 if not Is_Interface (T) then
15952 Diagnose_Interface (Intf, T);
15954 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
15955 -- a limited type from having a nonlimited progenitor.
15957 elsif (Limited_Present (Def)
15958 or else (not Is_Interface (Parent_Type)
15959 and then Is_Limited_Type (Parent_Type)))
15960 and then not Is_Limited_Interface (T)
15963 ("progenitor interface& of limited type must be limited",
15972 if Parent_Type = Any_Type
15973 or else Etype (Parent_Type) = Any_Type
15974 or else (Is_Class_Wide_Type (Parent_Type)
15975 and then Etype (Parent_Type) = T)
15977 -- If Parent_Type is undefined or illegal, make new type into a
15978 -- subtype of Any_Type, and set a few attributes to prevent cascaded
15979 -- errors. If this is a self-definition, emit error now.
15981 if T = Parent_Type or else T = Etype (Parent_Type) then
15982 Error_Msg_N ("type cannot be used in its own definition", Indic);
15985 Set_Ekind (T, Ekind (Parent_Type));
15986 Set_Etype (T, Any_Type);
15987 Set_Scalar_Range (T, Scalar_Range (Any_Type));
15989 if Is_Tagged_Type (T)
15990 and then Is_Record_Type (T)
15992 Set_Direct_Primitive_Operations (T, New_Elmt_List);
15998 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
15999 -- an interface is special because the list of interfaces in the full
16000 -- view can be given in any order. For example:
16002 -- type A is interface;
16003 -- type B is interface and A;
16004 -- type D is new B with private;
16006 -- type D is new A and B with null record; -- 1 --
16008 -- In this case we perform the following transformation of -1-:
16010 -- type D is new B and A with null record;
16012 -- If the parent of the full-view covers the parent of the partial-view
16013 -- we have two possible cases:
16015 -- 1) They have the same parent
16016 -- 2) The parent of the full-view implements some further interfaces
16018 -- In both cases we do not need to perform the transformation. In the
16019 -- first case the source program is correct and the transformation is
16020 -- not needed; in the second case the source program does not fulfill
16021 -- the no-hidden interfaces rule (AI-396) and the error will be reported
16024 -- This transformation not only simplifies the rest of the analysis of
16025 -- this type declaration but also simplifies the correct generation of
16026 -- the object layout to the expander.
16028 if In_Private_Part (Current_Scope)
16029 and then Is_Interface (Parent_Type)
16033 Partial_View : Entity_Id;
16034 Partial_View_Parent : Entity_Id;
16035 New_Iface : Node_Id;
16038 -- Look for the associated private type declaration
16040 Partial_View := First_Entity (Current_Scope);
16042 exit when No (Partial_View)
16043 or else (Has_Private_Declaration (Partial_View)
16044 and then Full_View (Partial_View) = T);
16046 Next_Entity (Partial_View);
16049 -- If the partial view was not found then the source code has
16050 -- errors and the transformation is not needed.
16052 if Present (Partial_View) then
16053 Partial_View_Parent := Etype (Partial_View);
16055 -- If the parent of the full-view covers the parent of the
16056 -- partial-view we have nothing else to do.
16058 if Interface_Present_In_Ancestor
16059 (Parent_Type, Partial_View_Parent)
16063 -- Traverse the list of interfaces of the full-view to look
16064 -- for the parent of the partial-view and perform the tree
16068 Iface := First (Interface_List (Def));
16069 while Present (Iface) loop
16070 if Etype (Iface) = Etype (Partial_View) then
16071 Rewrite (Subtype_Indication (Def),
16072 New_Copy (Subtype_Indication
16073 (Parent (Partial_View))));
16076 Make_Identifier (Sloc (N), Chars (Parent_Type));
16077 Append (New_Iface, Interface_List (Def));
16079 -- Analyze the transformed code
16081 Derived_Type_Declaration (T, N, Is_Completion);
16092 -- Only composite types other than array types are allowed to have
16095 if Present (Discriminant_Specifications (N)) then
16096 if (Is_Elementary_Type (Parent_Type)
16098 Is_Array_Type (Parent_Type))
16099 and then not Error_Posted (N)
16102 ("elementary or array type cannot have discriminants",
16103 Defining_Identifier (First (Discriminant_Specifications (N))));
16104 Set_Has_Discriminants (T, False);
16106 -- The type is allowed to have discriminants
16109 Check_SPARK_05_Restriction ("discriminant type is not allowed", N);
16113 -- In Ada 83, a derived type defined in a package specification cannot
16114 -- be used for further derivation until the end of its visible part.
16115 -- Note that derivation in the private part of the package is allowed.
16117 if Ada_Version = Ada_83
16118 and then Is_Derived_Type (Parent_Type)
16119 and then In_Visible_Part (Scope (Parent_Type))
16121 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
16123 ("(Ada 83): premature use of type for derivation", Indic);
16127 -- Check for early use of incomplete or private type
16129 if Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
16130 Error_Msg_N ("premature derivation of incomplete type", Indic);
16133 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
16134 and then not Comes_From_Generic (Parent_Type))
16135 or else Has_Private_Component (Parent_Type)
16137 -- The ancestor type of a formal type can be incomplete, in which
16138 -- case only the operations of the partial view are available in the
16139 -- generic. Subsequent checks may be required when the full view is
16140 -- analyzed to verify that a derivation from a tagged type has an
16143 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
16146 elsif No (Underlying_Type (Parent_Type))
16147 or else Has_Private_Component (Parent_Type)
16150 ("premature derivation of derived or private type", Indic);
16152 -- Flag the type itself as being in error, this prevents some
16153 -- nasty problems with subsequent uses of the malformed type.
16155 Set_Error_Posted (T);
16157 -- Check that within the immediate scope of an untagged partial
16158 -- view it's illegal to derive from the partial view if the
16159 -- full view is tagged. (7.3(7))
16161 -- We verify that the Parent_Type is a partial view by checking
16162 -- that it is not a Full_Type_Declaration (i.e. a private type or
16163 -- private extension declaration), to distinguish a partial view
16164 -- from a derivation from a private type which also appears as
16165 -- E_Private_Type. If the parent base type is not declared in an
16166 -- enclosing scope there is no need to check.
16168 elsif Present (Full_View (Parent_Type))
16169 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
16170 and then not Is_Tagged_Type (Parent_Type)
16171 and then Is_Tagged_Type (Full_View (Parent_Type))
16172 and then In_Open_Scopes (Scope (Base_Type (Parent_Type)))
16175 ("premature derivation from type with tagged full view",
16180 -- Check that form of derivation is appropriate
16182 Taggd := Is_Tagged_Type (Parent_Type);
16184 -- Set the parent type to the class-wide type's specific type in this
16185 -- case to prevent cascading errors
16187 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
16188 Error_Msg_N ("parent type must not be a class-wide type", Indic);
16189 Set_Etype (T, Etype (Parent_Type));
16193 if Present (Extension) and then not Taggd then
16195 ("type derived from untagged type cannot have extension", Indic);
16197 elsif No (Extension) and then Taggd then
16199 -- If this declaration is within a private part (or body) of a
16200 -- generic instantiation then the derivation is allowed (the parent
16201 -- type can only appear tagged in this case if it's a generic actual
16202 -- type, since it would otherwise have been rejected in the analysis
16203 -- of the generic template).
16205 if not Is_Generic_Actual_Type (Parent_Type)
16206 or else In_Visible_Part (Scope (Parent_Type))
16208 if Is_Class_Wide_Type (Parent_Type) then
16210 ("parent type must not be a class-wide type", Indic);
16212 -- Use specific type to prevent cascaded errors.
16214 Parent_Type := Etype (Parent_Type);
16218 ("type derived from tagged type must have extension", Indic);
16223 -- AI-443: Synchronized formal derived types require a private
16224 -- extension. There is no point in checking the ancestor type or
16225 -- the progenitors since the construct is wrong to begin with.
16227 if Ada_Version >= Ada_2005
16228 and then Is_Generic_Type (T)
16229 and then Present (Original_Node (N))
16232 Decl : constant Node_Id := Original_Node (N);
16235 if Nkind (Decl) = N_Formal_Type_Declaration
16236 and then Nkind (Formal_Type_Definition (Decl)) =
16237 N_Formal_Derived_Type_Definition
16238 and then Synchronized_Present (Formal_Type_Definition (Decl))
16239 and then No (Extension)
16241 -- Avoid emitting a duplicate error message
16243 and then not Error_Posted (Indic)
16246 ("synchronized derived type must have extension", N);
16251 if Null_Exclusion_Present (Def)
16252 and then not Is_Access_Type (Parent_Type)
16254 Error_Msg_N ("null exclusion can only apply to an access type", N);
16257 -- Avoid deriving parent primitives of underlying record views
16259 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
16260 Derive_Subps => not Is_Underlying_Record_View (T));
16262 -- AI-419: The parent type of an explicitly limited derived type must
16263 -- be a limited type or a limited interface.
16265 if Limited_Present (Def) then
16266 Set_Is_Limited_Record (T);
16268 if Is_Interface (T) then
16269 Set_Is_Limited_Interface (T);
16272 if not Is_Limited_Type (Parent_Type)
16274 (not Is_Interface (Parent_Type)
16275 or else not Is_Limited_Interface (Parent_Type))
16277 -- AI05-0096: a derivation in the private part of an instance is
16278 -- legal if the generic formal is untagged limited, and the actual
16281 if Is_Generic_Actual_Type (Parent_Type)
16282 and then In_Private_Part (Current_Scope)
16285 (Generic_Parent_Type (Parent (Parent_Type)))
16291 ("parent type& of limited type must be limited",
16297 -- In SPARK, there are no derived type definitions other than type
16298 -- extensions of tagged record types.
16300 if No (Extension) then
16301 Check_SPARK_05_Restriction
16302 ("derived type is not allowed", Original_Node (N));
16304 end Derived_Type_Declaration;
16306 ------------------------
16307 -- Diagnose_Interface --
16308 ------------------------
16310 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
16312 if not Is_Interface (E) and then E /= Any_Type then
16313 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
16315 end Diagnose_Interface;
16317 ----------------------------------
16318 -- Enumeration_Type_Declaration --
16319 ----------------------------------
16321 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
16328 -- Create identifier node representing lower bound
16330 B_Node := New_Node (N_Identifier, Sloc (Def));
16331 L := First (Literals (Def));
16332 Set_Chars (B_Node, Chars (L));
16333 Set_Entity (B_Node, L);
16334 Set_Etype (B_Node, T);
16335 Set_Is_Static_Expression (B_Node, True);
16337 R_Node := New_Node (N_Range, Sloc (Def));
16338 Set_Low_Bound (R_Node, B_Node);
16340 Set_Ekind (T, E_Enumeration_Type);
16341 Set_First_Literal (T, L);
16343 Set_Is_Constrained (T);
16347 -- Loop through literals of enumeration type setting pos and rep values
16348 -- except that if the Ekind is already set, then it means the literal
16349 -- was already constructed (case of a derived type declaration and we
16350 -- should not disturb the Pos and Rep values.
16352 while Present (L) loop
16353 if Ekind (L) /= E_Enumeration_Literal then
16354 Set_Ekind (L, E_Enumeration_Literal);
16355 Set_Enumeration_Pos (L, Ev);
16356 Set_Enumeration_Rep (L, Ev);
16357 Set_Is_Known_Valid (L, True);
16361 New_Overloaded_Entity (L);
16362 Generate_Definition (L);
16363 Set_Convention (L, Convention_Intrinsic);
16365 -- Case of character literal
16367 if Nkind (L) = N_Defining_Character_Literal then
16368 Set_Is_Character_Type (T, True);
16370 -- Check violation of No_Wide_Characters
16372 if Restriction_Check_Required (No_Wide_Characters) then
16373 Get_Name_String (Chars (L));
16375 if Name_Len >= 3 and then Name_Buffer (1 .. 2) = "QW" then
16376 Check_Restriction (No_Wide_Characters, L);
16385 -- Now create a node representing upper bound
16387 B_Node := New_Node (N_Identifier, Sloc (Def));
16388 Set_Chars (B_Node, Chars (Last (Literals (Def))));
16389 Set_Entity (B_Node, Last (Literals (Def)));
16390 Set_Etype (B_Node, T);
16391 Set_Is_Static_Expression (B_Node, True);
16393 Set_High_Bound (R_Node, B_Node);
16395 -- Initialize various fields of the type. Some of this information
16396 -- may be overwritten later through rep.clauses.
16398 Set_Scalar_Range (T, R_Node);
16399 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
16400 Set_Enum_Esize (T);
16401 Set_Enum_Pos_To_Rep (T, Empty);
16403 -- Set Discard_Names if configuration pragma set, or if there is
16404 -- a parameterless pragma in the current declarative region
16406 if Global_Discard_Names or else Discard_Names (Scope (T)) then
16407 Set_Discard_Names (T);
16410 -- Process end label if there is one
16412 if Present (Def) then
16413 Process_End_Label (Def, 'e', T);
16415 end Enumeration_Type_Declaration;
16417 ---------------------------------
16418 -- Expand_To_Stored_Constraint --
16419 ---------------------------------
16421 function Expand_To_Stored_Constraint
16423 Constraint : Elist_Id) return Elist_Id
16425 Explicitly_Discriminated_Type : Entity_Id;
16426 Expansion : Elist_Id;
16427 Discriminant : Entity_Id;
16429 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
16430 -- Find the nearest type that actually specifies discriminants
16432 ---------------------------------
16433 -- Type_With_Explicit_Discrims --
16434 ---------------------------------
16436 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
16437 Typ : constant E := Base_Type (Id);
16440 if Ekind (Typ) in Incomplete_Or_Private_Kind then
16441 if Present (Full_View (Typ)) then
16442 return Type_With_Explicit_Discrims (Full_View (Typ));
16446 if Has_Discriminants (Typ) then
16451 if Etype (Typ) = Typ then
16453 elsif Has_Discriminants (Typ) then
16456 return Type_With_Explicit_Discrims (Etype (Typ));
16459 end Type_With_Explicit_Discrims;
16461 -- Start of processing for Expand_To_Stored_Constraint
16464 if No (Constraint) or else Is_Empty_Elmt_List (Constraint) then
16468 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
16470 if No (Explicitly_Discriminated_Type) then
16474 Expansion := New_Elmt_List;
16477 First_Stored_Discriminant (Explicitly_Discriminated_Type);
16478 while Present (Discriminant) loop
16480 (Get_Discriminant_Value
16481 (Discriminant, Explicitly_Discriminated_Type, Constraint),
16483 Next_Stored_Discriminant (Discriminant);
16487 end Expand_To_Stored_Constraint;
16489 ---------------------------
16490 -- Find_Hidden_Interface --
16491 ---------------------------
16493 function Find_Hidden_Interface
16495 Dest : Elist_Id) return Entity_Id
16498 Iface_Elmt : Elmt_Id;
16501 if Present (Src) and then Present (Dest) then
16502 Iface_Elmt := First_Elmt (Src);
16503 while Present (Iface_Elmt) loop
16504 Iface := Node (Iface_Elmt);
16506 if Is_Interface (Iface)
16507 and then not Contain_Interface (Iface, Dest)
16512 Next_Elmt (Iface_Elmt);
16517 end Find_Hidden_Interface;
16519 --------------------
16520 -- Find_Type_Name --
16521 --------------------
16523 function Find_Type_Name (N : Node_Id) return Entity_Id is
16524 Id : constant Entity_Id := Defining_Identifier (N);
16525 New_Id : Entity_Id;
16527 Prev_Par : Node_Id;
16529 procedure Check_Duplicate_Aspects;
16530 -- Check that aspects specified in a completion have not been specified
16531 -- already in the partial view.
16533 procedure Tag_Mismatch;
16534 -- Diagnose a tagged partial view whose full view is untagged. We post
16535 -- the message on the full view, with a reference to the previous
16536 -- partial view. The partial view can be private or incomplete, and
16537 -- these are handled in a different manner, so we determine the position
16538 -- of the error message from the respective slocs of both.
16540 -----------------------------
16541 -- Check_Duplicate_Aspects --
16542 -----------------------------
16544 procedure Check_Duplicate_Aspects is
16545 function Get_Partial_View_Aspect (Asp : Node_Id) return Node_Id;
16546 -- Return the corresponding aspect of the partial view which matches
16547 -- the aspect id of Asp. Return Empty is no such aspect exists.
16549 -----------------------------
16550 -- Get_Partial_View_Aspect --
16551 -----------------------------
16553 function Get_Partial_View_Aspect (Asp : Node_Id) return Node_Id is
16554 Asp_Id : constant Aspect_Id := Get_Aspect_Id (Asp);
16555 Prev_Asps : constant List_Id := Aspect_Specifications (Prev_Par);
16556 Prev_Asp : Node_Id;
16559 if Present (Prev_Asps) then
16560 Prev_Asp := First (Prev_Asps);
16561 while Present (Prev_Asp) loop
16562 if Get_Aspect_Id (Prev_Asp) = Asp_Id then
16571 end Get_Partial_View_Aspect;
16575 Full_Asps : constant List_Id := Aspect_Specifications (N);
16576 Full_Asp : Node_Id;
16577 Part_Asp : Node_Id;
16579 -- Start of processing for Check_Duplicate_Aspects
16582 if Present (Full_Asps) then
16583 Full_Asp := First (Full_Asps);
16584 while Present (Full_Asp) loop
16585 Part_Asp := Get_Partial_View_Aspect (Full_Asp);
16587 -- An aspect and its class-wide counterpart are two distinct
16588 -- aspects and may apply to both views of an entity.
16590 if Present (Part_Asp)
16591 and then Class_Present (Part_Asp) = Class_Present (Full_Asp)
16594 ("aspect already specified in private declaration",
16601 if Has_Discriminants (Prev)
16602 and then not Has_Unknown_Discriminants (Prev)
16603 and then Get_Aspect_Id (Full_Asp) =
16604 Aspect_Implicit_Dereference
16607 ("cannot specify aspect if partial view has known "
16608 & "discriminants", Full_Asp);
16614 end Check_Duplicate_Aspects;
16620 procedure Tag_Mismatch is
16622 if Sloc (Prev) < Sloc (Id) then
16623 if Ada_Version >= Ada_2012
16624 and then Nkind (N) = N_Private_Type_Declaration
16627 ("declaration of private } must be a tagged type ", Id, Prev);
16630 ("full declaration of } must be a tagged type ", Id, Prev);
16634 if Ada_Version >= Ada_2012
16635 and then Nkind (N) = N_Private_Type_Declaration
16638 ("declaration of private } must be a tagged type ", Prev, Id);
16641 ("full declaration of } must be a tagged type ", Prev, Id);
16646 -- Start of processing for Find_Type_Name
16649 -- Find incomplete declaration, if one was given
16651 Prev := Current_Entity_In_Scope (Id);
16653 -- New type declaration
16659 -- Previous declaration exists
16662 Prev_Par := Parent (Prev);
16664 -- Error if not incomplete/private case except if previous
16665 -- declaration is implicit, etc. Enter_Name will emit error if
16668 if not Is_Incomplete_Or_Private_Type (Prev) then
16672 -- Check invalid completion of private or incomplete type
16674 elsif not Nkind_In (N, N_Full_Type_Declaration,
16675 N_Task_Type_Declaration,
16676 N_Protected_Type_Declaration)
16678 (Ada_Version < Ada_2012
16679 or else not Is_Incomplete_Type (Prev)
16680 or else not Nkind_In (N, N_Private_Type_Declaration,
16681 N_Private_Extension_Declaration))
16683 -- Completion must be a full type declarations (RM 7.3(4))
16685 Error_Msg_Sloc := Sloc (Prev);
16686 Error_Msg_NE ("invalid completion of }", Id, Prev);
16688 -- Set scope of Id to avoid cascaded errors. Entity is never
16689 -- examined again, except when saving globals in generics.
16691 Set_Scope (Id, Current_Scope);
16694 -- If this is a repeated incomplete declaration, no further
16695 -- checks are possible.
16697 if Nkind (N) = N_Incomplete_Type_Declaration then
16701 -- Case of full declaration of incomplete type
16703 elsif Ekind (Prev) = E_Incomplete_Type
16704 and then (Ada_Version < Ada_2012
16705 or else No (Full_View (Prev))
16706 or else not Is_Private_Type (Full_View (Prev)))
16708 -- Indicate that the incomplete declaration has a matching full
16709 -- declaration. The defining occurrence of the incomplete
16710 -- declaration remains the visible one, and the procedure
16711 -- Get_Full_View dereferences it whenever the type is used.
16713 if Present (Full_View (Prev)) then
16714 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
16717 Set_Full_View (Prev, Id);
16718 Append_Entity (Id, Current_Scope);
16719 Set_Is_Public (Id, Is_Public (Prev));
16720 Set_Is_Internal (Id);
16723 -- If the incomplete view is tagged, a class_wide type has been
16724 -- created already. Use it for the private type as well, in order
16725 -- to prevent multiple incompatible class-wide types that may be
16726 -- created for self-referential anonymous access components.
16728 if Is_Tagged_Type (Prev)
16729 and then Present (Class_Wide_Type (Prev))
16731 Set_Ekind (Id, Ekind (Prev)); -- will be reset later
16732 Set_Class_Wide_Type (Id, Class_Wide_Type (Prev));
16734 -- Type of the class-wide type is the current Id. Previously
16735 -- this was not done for private declarations because of order-
16736 -- of-elaboration issues in the back end, but gigi now handles
16739 Set_Etype (Class_Wide_Type (Id), Id);
16742 -- Case of full declaration of private type
16745 -- If the private type was a completion of an incomplete type then
16746 -- update Prev to reference the private type
16748 if Ada_Version >= Ada_2012
16749 and then Ekind (Prev) = E_Incomplete_Type
16750 and then Present (Full_View (Prev))
16751 and then Is_Private_Type (Full_View (Prev))
16753 Prev := Full_View (Prev);
16754 Prev_Par := Parent (Prev);
16757 if Nkind (N) = N_Full_Type_Declaration
16759 (Type_Definition (N), N_Record_Definition,
16760 N_Derived_Type_Definition)
16761 and then Interface_Present (Type_Definition (N))
16764 ("completion of private type cannot be an interface", N);
16767 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
16768 if Etype (Prev) /= Prev then
16770 -- Prev is a private subtype or a derived type, and needs
16773 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
16776 elsif Ekind (Prev) = E_Private_Type
16777 and then Nkind_In (N, N_Task_Type_Declaration,
16778 N_Protected_Type_Declaration)
16781 ("completion of nonlimited type cannot be limited", N);
16783 elsif Ekind (Prev) = E_Record_Type_With_Private
16784 and then Nkind_In (N, N_Task_Type_Declaration,
16785 N_Protected_Type_Declaration)
16787 if not Is_Limited_Record (Prev) then
16789 ("completion of nonlimited type cannot be limited", N);
16791 elsif No (Interface_List (N)) then
16793 ("completion of tagged private type must be tagged",
16798 -- Ada 2005 (AI-251): Private extension declaration of a task
16799 -- type or a protected type. This case arises when covering
16800 -- interface types.
16802 elsif Nkind_In (N, N_Task_Type_Declaration,
16803 N_Protected_Type_Declaration)
16807 elsif Nkind (N) /= N_Full_Type_Declaration
16808 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
16811 ("full view of private extension must be an extension", N);
16813 elsif not (Abstract_Present (Parent (Prev)))
16814 and then Abstract_Present (Type_Definition (N))
16817 ("full view of non-abstract extension cannot be abstract", N);
16820 if not In_Private_Part (Current_Scope) then
16822 ("declaration of full view must appear in private part", N);
16825 if Ada_Version >= Ada_2012 then
16826 Check_Duplicate_Aspects;
16829 Copy_And_Swap (Prev, Id);
16830 Set_Has_Private_Declaration (Prev);
16831 Set_Has_Private_Declaration (Id);
16833 -- AI12-0133: Indicate whether we have a partial view with
16834 -- unknown discriminants, in which case initialization of objects
16835 -- of the type do not receive an invariant check.
16837 Set_Partial_View_Has_Unknown_Discr
16838 (Prev, Has_Unknown_Discriminants (Id));
16840 -- Preserve aspect and iterator flags that may have been set on
16841 -- the partial view.
16843 Set_Has_Delayed_Aspects (Prev, Has_Delayed_Aspects (Id));
16844 Set_Has_Implicit_Dereference (Prev, Has_Implicit_Dereference (Id));
16846 -- If no error, propagate freeze_node from private to full view.
16847 -- It may have been generated for an early operational item.
16849 if Present (Freeze_Node (Id))
16850 and then Serious_Errors_Detected = 0
16851 and then No (Full_View (Id))
16853 Set_Freeze_Node (Prev, Freeze_Node (Id));
16854 Set_Freeze_Node (Id, Empty);
16855 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
16858 Set_Full_View (Id, Prev);
16862 -- Verify that full declaration conforms to partial one
16864 if Is_Incomplete_Or_Private_Type (Prev)
16865 and then Present (Discriminant_Specifications (Prev_Par))
16867 if Present (Discriminant_Specifications (N)) then
16868 if Ekind (Prev) = E_Incomplete_Type then
16869 Check_Discriminant_Conformance (N, Prev, Prev);
16871 Check_Discriminant_Conformance (N, Prev, Id);
16876 ("missing discriminants in full type declaration", N);
16878 -- To avoid cascaded errors on subsequent use, share the
16879 -- discriminants of the partial view.
16881 Set_Discriminant_Specifications (N,
16882 Discriminant_Specifications (Prev_Par));
16886 -- A prior untagged partial view can have an associated class-wide
16887 -- type due to use of the class attribute, and in this case the full
16888 -- type must also be tagged. This Ada 95 usage is deprecated in favor
16889 -- of incomplete tagged declarations, but we check for it.
16892 and then (Is_Tagged_Type (Prev)
16893 or else Present (Class_Wide_Type (Prev)))
16895 -- Ada 2012 (AI05-0162): A private type may be the completion of
16896 -- an incomplete type.
16898 if Ada_Version >= Ada_2012
16899 and then Is_Incomplete_Type (Prev)
16900 and then Nkind_In (N, N_Private_Type_Declaration,
16901 N_Private_Extension_Declaration)
16903 -- No need to check private extensions since they are tagged
16905 if Nkind (N) = N_Private_Type_Declaration
16906 and then not Tagged_Present (N)
16911 -- The full declaration is either a tagged type (including
16912 -- a synchronized type that implements interfaces) or a
16913 -- type extension, otherwise this is an error.
16915 elsif Nkind_In (N, N_Task_Type_Declaration,
16916 N_Protected_Type_Declaration)
16918 if No (Interface_List (N)) and then not Error_Posted (N) then
16922 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
16924 -- Indicate that the previous declaration (tagged incomplete
16925 -- or private declaration) requires the same on the full one.
16927 if not Tagged_Present (Type_Definition (N)) then
16929 Set_Is_Tagged_Type (Id);
16932 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
16933 if No (Record_Extension_Part (Type_Definition (N))) then
16935 ("full declaration of } must be a record extension",
16938 -- Set some attributes to produce a usable full view
16940 Set_Is_Tagged_Type (Id);
16949 and then Nkind (Parent (Prev)) = N_Incomplete_Type_Declaration
16950 and then Present (Premature_Use (Parent (Prev)))
16952 Error_Msg_Sloc := Sloc (N);
16954 ("\full declaration #", Premature_Use (Parent (Prev)));
16959 end Find_Type_Name;
16961 -------------------------
16962 -- Find_Type_Of_Object --
16963 -------------------------
16965 function Find_Type_Of_Object
16966 (Obj_Def : Node_Id;
16967 Related_Nod : Node_Id) return Entity_Id
16969 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
16970 P : Node_Id := Parent (Obj_Def);
16975 -- If the parent is a component_definition node we climb to the
16976 -- component_declaration node
16978 if Nkind (P) = N_Component_Definition then
16982 -- Case of an anonymous array subtype
16984 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
16985 N_Unconstrained_Array_Definition)
16988 Array_Type_Declaration (T, Obj_Def);
16990 -- Create an explicit subtype whenever possible
16992 elsif Nkind (P) /= N_Component_Declaration
16993 and then Def_Kind = N_Subtype_Indication
16995 -- Base name of subtype on object name, which will be unique in
16996 -- the current scope.
16998 -- If this is a duplicate declaration, return base type, to avoid
16999 -- generating duplicate anonymous types.
17001 if Error_Posted (P) then
17002 Analyze (Subtype_Mark (Obj_Def));
17003 return Entity (Subtype_Mark (Obj_Def));
17008 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
17010 T := Make_Defining_Identifier (Sloc (P), Nam);
17012 Insert_Action (Obj_Def,
17013 Make_Subtype_Declaration (Sloc (P),
17014 Defining_Identifier => T,
17015 Subtype_Indication => Relocate_Node (Obj_Def)));
17017 -- This subtype may need freezing, and this will not be done
17018 -- automatically if the object declaration is not in declarative
17019 -- part. Since this is an object declaration, the type cannot always
17020 -- be frozen here. Deferred constants do not freeze their type
17021 -- (which often enough will be private).
17023 if Nkind (P) = N_Object_Declaration
17024 and then Constant_Present (P)
17025 and then No (Expression (P))
17029 -- Here we freeze the base type of object type to catch premature use
17030 -- of discriminated private type without a full view.
17033 Insert_Actions (Obj_Def, Freeze_Entity (Base_Type (T), P));
17036 -- Ada 2005 AI-406: the object definition in an object declaration
17037 -- can be an access definition.
17039 elsif Def_Kind = N_Access_Definition then
17040 T := Access_Definition (Related_Nod, Obj_Def);
17042 Set_Is_Local_Anonymous_Access
17044 V => (Ada_Version < Ada_2012)
17045 or else (Nkind (P) /= N_Object_Declaration)
17046 or else Is_Library_Level_Entity (Defining_Identifier (P)));
17048 -- Otherwise, the object definition is just a subtype_mark
17051 T := Process_Subtype (Obj_Def, Related_Nod);
17053 -- If expansion is disabled an object definition that is an aggregate
17054 -- will not get expanded and may lead to scoping problems in the back
17055 -- end, if the object is referenced in an inner scope. In that case
17056 -- create an itype reference for the object definition now. This
17057 -- may be redundant in some cases, but harmless.
17060 and then Nkind (Related_Nod) = N_Object_Declaration
17063 Build_Itype_Reference (T, Related_Nod);
17068 end Find_Type_Of_Object;
17070 --------------------------------
17071 -- Find_Type_Of_Subtype_Indic --
17072 --------------------------------
17074 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
17078 -- Case of subtype mark with a constraint
17080 if Nkind (S) = N_Subtype_Indication then
17081 Find_Type (Subtype_Mark (S));
17082 Typ := Entity (Subtype_Mark (S));
17085 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
17088 ("incorrect constraint for this kind of type", Constraint (S));
17089 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
17092 -- Otherwise we have a subtype mark without a constraint
17094 elsif Error_Posted (S) then
17095 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
17103 -- Check No_Wide_Characters restriction
17105 Check_Wide_Character_Restriction (Typ, S);
17108 end Find_Type_Of_Subtype_Indic;
17110 -------------------------------------
17111 -- Floating_Point_Type_Declaration --
17112 -------------------------------------
17114 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
17115 Digs : constant Node_Id := Digits_Expression (Def);
17116 Max_Digs_Val : constant Uint := Digits_Value (Standard_Long_Long_Float);
17118 Base_Typ : Entity_Id;
17119 Implicit_Base : Entity_Id;
17122 function Can_Derive_From (E : Entity_Id) return Boolean;
17123 -- Find if given digits value, and possibly a specified range, allows
17124 -- derivation from specified type
17126 function Find_Base_Type return Entity_Id;
17127 -- Find a predefined base type that Def can derive from, or generate
17128 -- an error and substitute Long_Long_Float if none exists.
17130 ---------------------
17131 -- Can_Derive_From --
17132 ---------------------
17134 function Can_Derive_From (E : Entity_Id) return Boolean is
17135 Spec : constant Entity_Id := Real_Range_Specification (Def);
17138 -- Check specified "digits" constraint
17140 if Digs_Val > Digits_Value (E) then
17144 -- Check for matching range, if specified
17146 if Present (Spec) then
17147 if Expr_Value_R (Type_Low_Bound (E)) >
17148 Expr_Value_R (Low_Bound (Spec))
17153 if Expr_Value_R (Type_High_Bound (E)) <
17154 Expr_Value_R (High_Bound (Spec))
17161 end Can_Derive_From;
17163 --------------------
17164 -- Find_Base_Type --
17165 --------------------
17167 function Find_Base_Type return Entity_Id is
17168 Choice : Elmt_Id := First_Elmt (Predefined_Float_Types);
17171 -- Iterate over the predefined types in order, returning the first
17172 -- one that Def can derive from.
17174 while Present (Choice) loop
17175 if Can_Derive_From (Node (Choice)) then
17176 return Node (Choice);
17179 Next_Elmt (Choice);
17182 -- If we can't derive from any existing type, use Long_Long_Float
17183 -- and give appropriate message explaining the problem.
17185 if Digs_Val > Max_Digs_Val then
17186 -- It might be the case that there is a type with the requested
17187 -- range, just not the combination of digits and range.
17190 ("no predefined type has requested range and precision",
17191 Real_Range_Specification (Def));
17195 ("range too large for any predefined type",
17196 Real_Range_Specification (Def));
17199 return Standard_Long_Long_Float;
17200 end Find_Base_Type;
17202 -- Start of processing for Floating_Point_Type_Declaration
17205 Check_Restriction (No_Floating_Point, Def);
17207 -- Create an implicit base type
17210 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
17212 -- Analyze and verify digits value
17214 Analyze_And_Resolve (Digs, Any_Integer);
17215 Check_Digits_Expression (Digs);
17216 Digs_Val := Expr_Value (Digs);
17218 -- Process possible range spec and find correct type to derive from
17220 Process_Real_Range_Specification (Def);
17222 -- Check that requested number of digits is not too high.
17224 if Digs_Val > Max_Digs_Val then
17226 -- The check for Max_Base_Digits may be somewhat expensive, as it
17227 -- requires reading System, so only do it when necessary.
17230 Max_Base_Digits : constant Uint :=
17233 (Parent (RTE (RE_Max_Base_Digits))));
17236 if Digs_Val > Max_Base_Digits then
17237 Error_Msg_Uint_1 := Max_Base_Digits;
17238 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
17240 elsif No (Real_Range_Specification (Def)) then
17241 Error_Msg_Uint_1 := Max_Digs_Val;
17242 Error_Msg_N ("types with more than ^ digits need range spec "
17243 & "(RM 3.5.7(6))", Digs);
17248 -- Find a suitable type to derive from or complain and use a substitute
17250 Base_Typ := Find_Base_Type;
17252 -- If there are bounds given in the declaration use them as the bounds
17253 -- of the type, otherwise use the bounds of the predefined base type
17254 -- that was chosen based on the Digits value.
17256 if Present (Real_Range_Specification (Def)) then
17257 Set_Scalar_Range (T, Real_Range_Specification (Def));
17258 Set_Is_Constrained (T);
17260 -- The bounds of this range must be converted to machine numbers
17261 -- in accordance with RM 4.9(38).
17263 Bound := Type_Low_Bound (T);
17265 if Nkind (Bound) = N_Real_Literal then
17267 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
17268 Set_Is_Machine_Number (Bound);
17271 Bound := Type_High_Bound (T);
17273 if Nkind (Bound) = N_Real_Literal then
17275 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
17276 Set_Is_Machine_Number (Bound);
17280 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
17283 -- Complete definition of implicit base and declared first subtype. The
17284 -- inheritance of the rep item chain ensures that SPARK-related pragmas
17285 -- are not clobbered when the floating point type acts as a full view of
17288 Set_Etype (Implicit_Base, Base_Typ);
17289 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
17290 Set_Size_Info (Implicit_Base, Base_Typ);
17291 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
17292 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
17293 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
17294 Set_Float_Rep (Implicit_Base, Float_Rep (Base_Typ));
17296 Set_Ekind (T, E_Floating_Point_Subtype);
17297 Set_Etype (T, Implicit_Base);
17298 Set_Size_Info (T, Implicit_Base);
17299 Set_RM_Size (T, RM_Size (Implicit_Base));
17300 Inherit_Rep_Item_Chain (T, Implicit_Base);
17301 Set_Digits_Value (T, Digs_Val);
17302 end Floating_Point_Type_Declaration;
17304 ----------------------------
17305 -- Get_Discriminant_Value --
17306 ----------------------------
17308 -- This is the situation:
17310 -- There is a non-derived type
17312 -- type T0 (Dx, Dy, Dz...)
17314 -- There are zero or more levels of derivation, with each derivation
17315 -- either purely inheriting the discriminants, or defining its own.
17317 -- type Ti is new Ti-1
17319 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
17321 -- subtype Ti is ...
17323 -- The subtype issue is avoided by the use of Original_Record_Component,
17324 -- and the fact that derived subtypes also derive the constraints.
17326 -- This chain leads back from
17328 -- Typ_For_Constraint
17330 -- Typ_For_Constraint has discriminants, and the value for each
17331 -- discriminant is given by its corresponding Elmt of Constraints.
17333 -- Discriminant is some discriminant in this hierarchy
17335 -- We need to return its value
17337 -- We do this by recursively searching each level, and looking for
17338 -- Discriminant. Once we get to the bottom, we start backing up
17339 -- returning the value for it which may in turn be a discriminant
17340 -- further up, so on the backup we continue the substitution.
17342 function Get_Discriminant_Value
17343 (Discriminant : Entity_Id;
17344 Typ_For_Constraint : Entity_Id;
17345 Constraint : Elist_Id) return Node_Id
17347 function Root_Corresponding_Discriminant
17348 (Discr : Entity_Id) return Entity_Id;
17349 -- Given a discriminant, traverse the chain of inherited discriminants
17350 -- and return the topmost discriminant.
17352 function Search_Derivation_Levels
17354 Discrim_Values : Elist_Id;
17355 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
17356 -- This is the routine that performs the recursive search of levels
17357 -- as described above.
17359 -------------------------------------
17360 -- Root_Corresponding_Discriminant --
17361 -------------------------------------
17363 function Root_Corresponding_Discriminant
17364 (Discr : Entity_Id) return Entity_Id
17370 while Present (Corresponding_Discriminant (D)) loop
17371 D := Corresponding_Discriminant (D);
17375 end Root_Corresponding_Discriminant;
17377 ------------------------------
17378 -- Search_Derivation_Levels --
17379 ------------------------------
17381 function Search_Derivation_Levels
17383 Discrim_Values : Elist_Id;
17384 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
17388 Result : Node_Or_Entity_Id;
17389 Result_Entity : Node_Id;
17392 -- If inappropriate type, return Error, this happens only in
17393 -- cascaded error situations, and we want to avoid a blow up.
17395 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
17399 -- Look deeper if possible. Use Stored_Constraints only for
17400 -- untagged types. For tagged types use the given constraint.
17401 -- This asymmetry needs explanation???
17403 if not Stored_Discrim_Values
17404 and then Present (Stored_Constraint (Ti))
17405 and then not Is_Tagged_Type (Ti)
17408 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
17411 Td : constant Entity_Id := Etype (Ti);
17415 Result := Discriminant;
17418 if Present (Stored_Constraint (Ti)) then
17420 Search_Derivation_Levels
17421 (Td, Stored_Constraint (Ti), True);
17424 Search_Derivation_Levels
17425 (Td, Discrim_Values, Stored_Discrim_Values);
17431 -- Extra underlying places to search, if not found above. For
17432 -- concurrent types, the relevant discriminant appears in the
17433 -- corresponding record. For a type derived from a private type
17434 -- without discriminant, the full view inherits the discriminants
17435 -- of the full view of the parent.
17437 if Result = Discriminant then
17438 if Is_Concurrent_Type (Ti)
17439 and then Present (Corresponding_Record_Type (Ti))
17442 Search_Derivation_Levels (
17443 Corresponding_Record_Type (Ti),
17445 Stored_Discrim_Values);
17447 elsif Is_Private_Type (Ti)
17448 and then not Has_Discriminants (Ti)
17449 and then Present (Full_View (Ti))
17450 and then Etype (Full_View (Ti)) /= Ti
17453 Search_Derivation_Levels (
17456 Stored_Discrim_Values);
17460 -- If Result is not a (reference to a) discriminant, return it,
17461 -- otherwise set Result_Entity to the discriminant.
17463 if Nkind (Result) = N_Defining_Identifier then
17464 pragma Assert (Result = Discriminant);
17465 Result_Entity := Result;
17468 if not Denotes_Discriminant (Result) then
17472 Result_Entity := Entity (Result);
17475 -- See if this level of derivation actually has discriminants because
17476 -- tagged derivations can add them, hence the lower levels need not
17479 if not Has_Discriminants (Ti) then
17483 -- Scan Ti's discriminants for Result_Entity, and return its
17484 -- corresponding value, if any.
17486 Result_Entity := Original_Record_Component (Result_Entity);
17488 Assoc := First_Elmt (Discrim_Values);
17490 if Stored_Discrim_Values then
17491 Disc := First_Stored_Discriminant (Ti);
17493 Disc := First_Discriminant (Ti);
17496 while Present (Disc) loop
17497 pragma Assert (Present (Assoc));
17499 if Original_Record_Component (Disc) = Result_Entity then
17500 return Node (Assoc);
17505 if Stored_Discrim_Values then
17506 Next_Stored_Discriminant (Disc);
17508 Next_Discriminant (Disc);
17512 -- Could not find it
17515 end Search_Derivation_Levels;
17519 Result : Node_Or_Entity_Id;
17521 -- Start of processing for Get_Discriminant_Value
17524 -- ??? This routine is a gigantic mess and will be deleted. For the
17525 -- time being just test for the trivial case before calling recurse.
17527 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
17533 D := First_Discriminant (Typ_For_Constraint);
17534 E := First_Elmt (Constraint);
17535 while Present (D) loop
17536 if Chars (D) = Chars (Discriminant) then
17540 Next_Discriminant (D);
17546 Result := Search_Derivation_Levels
17547 (Typ_For_Constraint, Constraint, False);
17549 -- ??? hack to disappear when this routine is gone
17551 if Nkind (Result) = N_Defining_Identifier then
17557 D := First_Discriminant (Typ_For_Constraint);
17558 E := First_Elmt (Constraint);
17559 while Present (D) loop
17560 if Root_Corresponding_Discriminant (D) = Discriminant then
17564 Next_Discriminant (D);
17570 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
17572 end Get_Discriminant_Value;
17574 --------------------------
17575 -- Has_Range_Constraint --
17576 --------------------------
17578 function Has_Range_Constraint (N : Node_Id) return Boolean is
17579 C : constant Node_Id := Constraint (N);
17582 if Nkind (C) = N_Range_Constraint then
17585 elsif Nkind (C) = N_Digits_Constraint then
17587 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
17588 or else Present (Range_Constraint (C));
17590 elsif Nkind (C) = N_Delta_Constraint then
17591 return Present (Range_Constraint (C));
17596 end Has_Range_Constraint;
17598 ------------------------
17599 -- Inherit_Components --
17600 ------------------------
17602 function Inherit_Components
17604 Parent_Base : Entity_Id;
17605 Derived_Base : Entity_Id;
17606 Is_Tagged : Boolean;
17607 Inherit_Discr : Boolean;
17608 Discs : Elist_Id) return Elist_Id
17610 Assoc_List : constant Elist_Id := New_Elmt_List;
17612 procedure Inherit_Component
17613 (Old_C : Entity_Id;
17614 Plain_Discrim : Boolean := False;
17615 Stored_Discrim : Boolean := False);
17616 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
17617 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
17618 -- True, Old_C is a stored discriminant. If they are both false then
17619 -- Old_C is a regular component.
17621 -----------------------
17622 -- Inherit_Component --
17623 -----------------------
17625 procedure Inherit_Component
17626 (Old_C : Entity_Id;
17627 Plain_Discrim : Boolean := False;
17628 Stored_Discrim : Boolean := False)
17630 procedure Set_Anonymous_Type (Id : Entity_Id);
17631 -- Id denotes the entity of an access discriminant or anonymous
17632 -- access component. Set the type of Id to either the same type of
17633 -- Old_C or create a new one depending on whether the parent and
17634 -- the child types are in the same scope.
17636 ------------------------
17637 -- Set_Anonymous_Type --
17638 ------------------------
17640 procedure Set_Anonymous_Type (Id : Entity_Id) is
17641 Old_Typ : constant Entity_Id := Etype (Old_C);
17644 if Scope (Parent_Base) = Scope (Derived_Base) then
17645 Set_Etype (Id, Old_Typ);
17647 -- The parent and the derived type are in two different scopes.
17648 -- Reuse the type of the original discriminant / component by
17649 -- copying it in order to preserve all attributes.
17653 Typ : constant Entity_Id := New_Copy (Old_Typ);
17656 Set_Etype (Id, Typ);
17658 -- Since we do not generate component declarations for
17659 -- inherited components, associate the itype with the
17662 Set_Associated_Node_For_Itype (Typ, Parent (Derived_Base));
17663 Set_Scope (Typ, Derived_Base);
17666 end Set_Anonymous_Type;
17668 -- Local variables and constants
17670 New_C : constant Entity_Id := New_Copy (Old_C);
17672 Corr_Discrim : Entity_Id;
17673 Discrim : Entity_Id;
17675 -- Start of processing for Inherit_Component
17678 pragma Assert (not Is_Tagged or not Stored_Discrim);
17680 Set_Parent (New_C, Parent (Old_C));
17682 -- Regular discriminants and components must be inserted in the scope
17683 -- of the Derived_Base. Do it here.
17685 if not Stored_Discrim then
17686 Enter_Name (New_C);
17689 -- For tagged types the Original_Record_Component must point to
17690 -- whatever this field was pointing to in the parent type. This has
17691 -- already been achieved by the call to New_Copy above.
17693 if not Is_Tagged then
17694 Set_Original_Record_Component (New_C, New_C);
17697 -- Set the proper type of an access discriminant
17699 if Ekind (New_C) = E_Discriminant
17700 and then Ekind (Etype (New_C)) = E_Anonymous_Access_Type
17702 Set_Anonymous_Type (New_C);
17705 -- If we have inherited a component then see if its Etype contains
17706 -- references to Parent_Base discriminants. In this case, replace
17707 -- these references with the constraints given in Discs. We do not
17708 -- do this for the partial view of private types because this is
17709 -- not needed (only the components of the full view will be used
17710 -- for code generation) and cause problem. We also avoid this
17711 -- transformation in some error situations.
17713 if Ekind (New_C) = E_Component then
17715 -- Set the proper type of an anonymous access component
17717 if Ekind (Etype (New_C)) = E_Anonymous_Access_Type then
17718 Set_Anonymous_Type (New_C);
17720 elsif (Is_Private_Type (Derived_Base)
17721 and then not Is_Generic_Type (Derived_Base))
17722 or else (Is_Empty_Elmt_List (Discs)
17723 and then not Expander_Active)
17725 Set_Etype (New_C, Etype (Old_C));
17728 -- The current component introduces a circularity of the
17731 -- limited with Pack_2;
17732 -- package Pack_1 is
17733 -- type T_1 is tagged record
17734 -- Comp : access Pack_2.T_2;
17740 -- package Pack_2 is
17741 -- type T_2 is new Pack_1.T_1 with ...;
17746 Constrain_Component_Type
17747 (Old_C, Derived_Base, N, Parent_Base, Discs));
17751 -- In derived tagged types it is illegal to reference a non
17752 -- discriminant component in the parent type. To catch this, mark
17753 -- these components with an Ekind of E_Void. This will be reset in
17754 -- Record_Type_Definition after processing the record extension of
17755 -- the derived type.
17757 -- If the declaration is a private extension, there is no further
17758 -- record extension to process, and the components retain their
17759 -- current kind, because they are visible at this point.
17761 if Is_Tagged and then Ekind (New_C) = E_Component
17762 and then Nkind (N) /= N_Private_Extension_Declaration
17764 Set_Ekind (New_C, E_Void);
17767 if Plain_Discrim then
17768 Set_Corresponding_Discriminant (New_C, Old_C);
17769 Build_Discriminal (New_C);
17771 -- If we are explicitly inheriting a stored discriminant it will be
17772 -- completely hidden.
17774 elsif Stored_Discrim then
17775 Set_Corresponding_Discriminant (New_C, Empty);
17776 Set_Discriminal (New_C, Empty);
17777 Set_Is_Completely_Hidden (New_C);
17779 -- Set the Original_Record_Component of each discriminant in the
17780 -- derived base to point to the corresponding stored that we just
17783 Discrim := First_Discriminant (Derived_Base);
17784 while Present (Discrim) loop
17785 Corr_Discrim := Corresponding_Discriminant (Discrim);
17787 -- Corr_Discrim could be missing in an error situation
17789 if Present (Corr_Discrim)
17790 and then Original_Record_Component (Corr_Discrim) = Old_C
17792 Set_Original_Record_Component (Discrim, New_C);
17795 Next_Discriminant (Discrim);
17798 Append_Entity (New_C, Derived_Base);
17801 if not Is_Tagged then
17802 Append_Elmt (Old_C, Assoc_List);
17803 Append_Elmt (New_C, Assoc_List);
17805 end Inherit_Component;
17807 -- Variables local to Inherit_Component
17809 Loc : constant Source_Ptr := Sloc (N);
17811 Parent_Discrim : Entity_Id;
17812 Stored_Discrim : Entity_Id;
17814 Component : Entity_Id;
17816 -- Start of processing for Inherit_Components
17819 if not Is_Tagged then
17820 Append_Elmt (Parent_Base, Assoc_List);
17821 Append_Elmt (Derived_Base, Assoc_List);
17824 -- Inherit parent discriminants if needed
17826 if Inherit_Discr then
17827 Parent_Discrim := First_Discriminant (Parent_Base);
17828 while Present (Parent_Discrim) loop
17829 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
17830 Next_Discriminant (Parent_Discrim);
17834 -- Create explicit stored discrims for untagged types when necessary
17836 if not Has_Unknown_Discriminants (Derived_Base)
17837 and then Has_Discriminants (Parent_Base)
17838 and then not Is_Tagged
17841 or else First_Discriminant (Parent_Base) /=
17842 First_Stored_Discriminant (Parent_Base))
17844 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
17845 while Present (Stored_Discrim) loop
17846 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
17847 Next_Stored_Discriminant (Stored_Discrim);
17851 -- See if we can apply the second transformation for derived types, as
17852 -- explained in point 6. in the comments above Build_Derived_Record_Type
17853 -- This is achieved by appending Derived_Base discriminants into Discs,
17854 -- which has the side effect of returning a non empty Discs list to the
17855 -- caller of Inherit_Components, which is what we want. This must be
17856 -- done for private derived types if there are explicit stored
17857 -- discriminants, to ensure that we can retrieve the values of the
17858 -- constraints provided in the ancestors.
17861 and then Is_Empty_Elmt_List (Discs)
17862 and then Present (First_Discriminant (Derived_Base))
17864 (not Is_Private_Type (Derived_Base)
17865 or else Is_Completely_Hidden
17866 (First_Stored_Discriminant (Derived_Base))
17867 or else Is_Generic_Type (Derived_Base))
17869 D := First_Discriminant (Derived_Base);
17870 while Present (D) loop
17871 Append_Elmt (New_Occurrence_Of (D, Loc), Discs);
17872 Next_Discriminant (D);
17876 -- Finally, inherit non-discriminant components unless they are not
17877 -- visible because defined or inherited from the full view of the
17878 -- parent. Don't inherit the _parent field of the parent type.
17880 Component := First_Entity (Parent_Base);
17881 while Present (Component) loop
17883 -- Ada 2005 (AI-251): Do not inherit components associated with
17884 -- secondary tags of the parent.
17886 if Ekind (Component) = E_Component
17887 and then Present (Related_Type (Component))
17891 elsif Ekind (Component) /= E_Component
17892 or else Chars (Component) = Name_uParent
17896 -- If the derived type is within the parent type's declarative
17897 -- region, then the components can still be inherited even though
17898 -- they aren't visible at this point. This can occur for cases
17899 -- such as within public child units where the components must
17900 -- become visible upon entering the child unit's private part.
17902 elsif not Is_Visible_Component (Component)
17903 and then not In_Open_Scopes (Scope (Parent_Base))
17907 elsif Ekind_In (Derived_Base, E_Private_Type,
17908 E_Limited_Private_Type)
17913 Inherit_Component (Component);
17916 Next_Entity (Component);
17919 -- For tagged derived types, inherited discriminants cannot be used in
17920 -- component declarations of the record extension part. To achieve this
17921 -- we mark the inherited discriminants as not visible.
17923 if Is_Tagged and then Inherit_Discr then
17924 D := First_Discriminant (Derived_Base);
17925 while Present (D) loop
17926 Set_Is_Immediately_Visible (D, False);
17927 Next_Discriminant (D);
17932 end Inherit_Components;
17934 -----------------------------
17935 -- Inherit_Predicate_Flags --
17936 -----------------------------
17938 procedure Inherit_Predicate_Flags (Subt, Par : Entity_Id) is
17940 Set_Has_Predicates (Subt, Has_Predicates (Par));
17941 Set_Has_Static_Predicate_Aspect
17942 (Subt, Has_Static_Predicate_Aspect (Par));
17943 Set_Has_Dynamic_Predicate_Aspect
17944 (Subt, Has_Dynamic_Predicate_Aspect (Par));
17945 end Inherit_Predicate_Flags;
17947 ----------------------
17948 -- Is_EVF_Procedure --
17949 ----------------------
17951 function Is_EVF_Procedure (Subp : Entity_Id) return Boolean is
17952 Formal : Entity_Id;
17955 -- Examine the formals of an Extensions_Visible False procedure looking
17956 -- for a controlling OUT parameter.
17958 if Ekind (Subp) = E_Procedure
17959 and then Extensions_Visible_Status (Subp) = Extensions_Visible_False
17961 Formal := First_Formal (Subp);
17962 while Present (Formal) loop
17963 if Ekind (Formal) = E_Out_Parameter
17964 and then Is_Controlling_Formal (Formal)
17969 Next_Formal (Formal);
17974 end Is_EVF_Procedure;
17976 -----------------------
17977 -- Is_Null_Extension --
17978 -----------------------
17980 function Is_Null_Extension (T : Entity_Id) return Boolean is
17981 Type_Decl : constant Node_Id := Parent (Base_Type (T));
17982 Comp_List : Node_Id;
17986 if Nkind (Type_Decl) /= N_Full_Type_Declaration
17987 or else not Is_Tagged_Type (T)
17988 or else Nkind (Type_Definition (Type_Decl)) /=
17989 N_Derived_Type_Definition
17990 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
17996 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
17998 if Present (Discriminant_Specifications (Type_Decl)) then
18001 elsif Present (Comp_List)
18002 and then Is_Non_Empty_List (Component_Items (Comp_List))
18004 Comp := First (Component_Items (Comp_List));
18006 -- Only user-defined components are relevant. The component list
18007 -- may also contain a parent component and internal components
18008 -- corresponding to secondary tags, but these do not determine
18009 -- whether this is a null extension.
18011 while Present (Comp) loop
18012 if Comes_From_Source (Comp) then
18024 end Is_Null_Extension;
18026 ------------------------------
18027 -- Is_Valid_Constraint_Kind --
18028 ------------------------------
18030 function Is_Valid_Constraint_Kind
18031 (T_Kind : Type_Kind;
18032 Constraint_Kind : Node_Kind) return Boolean
18036 when Enumeration_Kind |
18038 return Constraint_Kind = N_Range_Constraint;
18040 when Decimal_Fixed_Point_Kind =>
18041 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
18042 N_Range_Constraint);
18044 when Ordinary_Fixed_Point_Kind =>
18045 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
18046 N_Range_Constraint);
18049 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
18050 N_Range_Constraint);
18057 E_Incomplete_Type |
18060 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
18063 return True; -- Error will be detected later
18065 end Is_Valid_Constraint_Kind;
18067 --------------------------
18068 -- Is_Visible_Component --
18069 --------------------------
18071 function Is_Visible_Component
18073 N : Node_Id := Empty) return Boolean
18075 Original_Comp : Entity_Id := Empty;
18076 Original_Type : Entity_Id;
18077 Type_Scope : Entity_Id;
18079 function Is_Local_Type (Typ : Entity_Id) return Boolean;
18080 -- Check whether parent type of inherited component is declared locally,
18081 -- possibly within a nested package or instance. The current scope is
18082 -- the derived record itself.
18084 -------------------
18085 -- Is_Local_Type --
18086 -------------------
18088 function Is_Local_Type (Typ : Entity_Id) return Boolean is
18092 Scop := Scope (Typ);
18093 while Present (Scop)
18094 and then Scop /= Standard_Standard
18096 if Scop = Scope (Current_Scope) then
18100 Scop := Scope (Scop);
18106 -- Start of processing for Is_Visible_Component
18109 if Ekind_In (C, E_Component, E_Discriminant) then
18110 Original_Comp := Original_Record_Component (C);
18113 if No (Original_Comp) then
18115 -- Premature usage, or previous error
18120 Original_Type := Scope (Original_Comp);
18121 Type_Scope := Scope (Base_Type (Scope (C)));
18124 -- This test only concerns tagged types
18126 if not Is_Tagged_Type (Original_Type) then
18129 -- If it is _Parent or _Tag, there is no visibility issue
18131 elsif not Comes_From_Source (Original_Comp) then
18134 -- Discriminants are visible unless the (private) type has unknown
18135 -- discriminants. If the discriminant reference is inserted for a
18136 -- discriminant check on a full view it is also visible.
18138 elsif Ekind (Original_Comp) = E_Discriminant
18140 (not Has_Unknown_Discriminants (Original_Type)
18141 or else (Present (N)
18142 and then Nkind (N) = N_Selected_Component
18143 and then Nkind (Prefix (N)) = N_Type_Conversion
18144 and then not Comes_From_Source (Prefix (N))))
18148 -- In the body of an instantiation, check the visibility of a component
18149 -- in case it has a homograph that is a primitive operation of a private
18150 -- type which was not visible in the generic unit.
18152 -- Should Is_Prefixed_Call be propagated from template to instance???
18154 elsif In_Instance_Body then
18155 if not Is_Tagged_Type (Original_Type)
18156 or else not Is_Private_Type (Original_Type)
18162 Subp_Elmt : Elmt_Id;
18165 Subp_Elmt := First_Elmt (Primitive_Operations (Original_Type));
18166 while Present (Subp_Elmt) loop
18168 -- The component is hidden by a primitive operation
18170 if Chars (Node (Subp_Elmt)) = Chars (C) then
18174 Next_Elmt (Subp_Elmt);
18181 -- If the component has been declared in an ancestor which is currently
18182 -- a private type, then it is not visible. The same applies if the
18183 -- component's containing type is not in an open scope and the original
18184 -- component's enclosing type is a visible full view of a private type
18185 -- (which can occur in cases where an attempt is being made to reference
18186 -- a component in a sibling package that is inherited from a visible
18187 -- component of a type in an ancestor package; the component in the
18188 -- sibling package should not be visible even though the component it
18189 -- inherited from is visible). This does not apply however in the case
18190 -- where the scope of the type is a private child unit, or when the
18191 -- parent comes from a local package in which the ancestor is currently
18192 -- visible. The latter suppression of visibility is needed for cases
18193 -- that are tested in B730006.
18195 elsif Is_Private_Type (Original_Type)
18197 (not Is_Private_Descendant (Type_Scope)
18198 and then not In_Open_Scopes (Type_Scope)
18199 and then Has_Private_Declaration (Original_Type))
18201 -- If the type derives from an entity in a formal package, there
18202 -- are no additional visible components.
18204 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
18205 N_Formal_Package_Declaration
18209 -- if we are not in the private part of the current package, there
18210 -- are no additional visible components.
18212 elsif Ekind (Scope (Current_Scope)) = E_Package
18213 and then not In_Private_Part (Scope (Current_Scope))
18218 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
18219 and then In_Open_Scopes (Scope (Original_Type))
18220 and then Is_Local_Type (Type_Scope);
18223 -- There is another weird way in which a component may be invisible when
18224 -- the private and the full view are not derived from the same ancestor.
18225 -- Here is an example :
18227 -- type A1 is tagged record F1 : integer; end record;
18228 -- type A2 is new A1 with record F2 : integer; end record;
18229 -- type T is new A1 with private;
18231 -- type T is new A2 with null record;
18233 -- In this case, the full view of T inherits F1 and F2 but the private
18234 -- view inherits only F1
18238 Ancestor : Entity_Id := Scope (C);
18242 if Ancestor = Original_Type then
18245 -- The ancestor may have a partial view of the original type,
18246 -- but if the full view is in scope, as in a child body, the
18247 -- component is visible.
18249 elsif In_Private_Part (Scope (Original_Type))
18250 and then Full_View (Ancestor) = Original_Type
18254 elsif Ancestor = Etype (Ancestor) then
18256 -- No further ancestors to examine
18261 Ancestor := Etype (Ancestor);
18265 end Is_Visible_Component;
18267 --------------------------
18268 -- Make_Class_Wide_Type --
18269 --------------------------
18271 procedure Make_Class_Wide_Type (T : Entity_Id) is
18272 CW_Type : Entity_Id;
18274 Next_E : Entity_Id;
18277 if Present (Class_Wide_Type (T)) then
18279 -- The class-wide type is a partially decorated entity created for a
18280 -- unanalyzed tagged type referenced through a limited with clause.
18281 -- When the tagged type is analyzed, its class-wide type needs to be
18282 -- redecorated. Note that we reuse the entity created by Decorate_
18283 -- Tagged_Type in order to preserve all links.
18285 if Materialize_Entity (Class_Wide_Type (T)) then
18286 CW_Type := Class_Wide_Type (T);
18287 Set_Materialize_Entity (CW_Type, False);
18289 -- The class wide type can have been defined by the partial view, in
18290 -- which case everything is already done.
18296 -- Default case, we need to create a new class-wide type
18300 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
18303 -- Inherit root type characteristics
18305 CW_Name := Chars (CW_Type);
18306 Next_E := Next_Entity (CW_Type);
18307 Copy_Node (T, CW_Type);
18308 Set_Comes_From_Source (CW_Type, False);
18309 Set_Chars (CW_Type, CW_Name);
18310 Set_Parent (CW_Type, Parent (T));
18311 Set_Next_Entity (CW_Type, Next_E);
18313 -- Ensure we have a new freeze node for the class-wide type. The partial
18314 -- view may have freeze action of its own, requiring a proper freeze
18315 -- node, and the same freeze node cannot be shared between the two
18318 Set_Has_Delayed_Freeze (CW_Type);
18319 Set_Freeze_Node (CW_Type, Empty);
18321 -- Customize the class-wide type: It has no prim. op., it cannot be
18322 -- abstract and its Etype points back to the specific root type.
18324 Set_Ekind (CW_Type, E_Class_Wide_Type);
18325 Set_Is_Tagged_Type (CW_Type, True);
18326 Set_Direct_Primitive_Operations (CW_Type, New_Elmt_List);
18327 Set_Is_Abstract_Type (CW_Type, False);
18328 Set_Is_Constrained (CW_Type, False);
18329 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
18330 Set_Default_SSO (CW_Type);
18332 if Ekind (T) = E_Class_Wide_Subtype then
18333 Set_Etype (CW_Type, Etype (Base_Type (T)));
18335 Set_Etype (CW_Type, T);
18338 Set_No_Tagged_Streams_Pragma (CW_Type, No_Tagged_Streams);
18340 -- If this is the class_wide type of a constrained subtype, it does
18341 -- not have discriminants.
18343 Set_Has_Discriminants (CW_Type,
18344 Has_Discriminants (T) and then not Is_Constrained (T));
18346 Set_Has_Unknown_Discriminants (CW_Type, True);
18347 Set_Class_Wide_Type (T, CW_Type);
18348 Set_Equivalent_Type (CW_Type, Empty);
18350 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
18352 Set_Class_Wide_Type (CW_Type, CW_Type);
18354 -- Inherit the "ghostness" from the root tagged type
18356 if Ghost_Mode > None or else Is_Ghost_Entity (T) then
18357 Set_Is_Ghost_Entity (CW_Type);
18359 end Make_Class_Wide_Type;
18365 procedure Make_Index
18367 Related_Nod : Node_Id;
18368 Related_Id : Entity_Id := Empty;
18369 Suffix_Index : Nat := 1;
18370 In_Iter_Schm : Boolean := False)
18374 Def_Id : Entity_Id := Empty;
18375 Found : Boolean := False;
18378 -- For a discrete range used in a constrained array definition and
18379 -- defined by a range, an implicit conversion to the predefined type
18380 -- INTEGER is assumed if each bound is either a numeric literal, a named
18381 -- number, or an attribute, and the type of both bounds (prior to the
18382 -- implicit conversion) is the type universal_integer. Otherwise, both
18383 -- bounds must be of the same discrete type, other than universal
18384 -- integer; this type must be determinable independently of the
18385 -- context, but using the fact that the type must be discrete and that
18386 -- both bounds must have the same type.
18388 -- Character literals also have a universal type in the absence of
18389 -- of additional context, and are resolved to Standard_Character.
18391 if Nkind (N) = N_Range then
18393 -- The index is given by a range constraint. The bounds are known
18394 -- to be of a consistent type.
18396 if not Is_Overloaded (N) then
18399 -- For universal bounds, choose the specific predefined type
18401 if T = Universal_Integer then
18402 T := Standard_Integer;
18404 elsif T = Any_Character then
18405 Ambiguous_Character (Low_Bound (N));
18407 T := Standard_Character;
18410 -- The node may be overloaded because some user-defined operators
18411 -- are available, but if a universal interpretation exists it is
18412 -- also the selected one.
18414 elsif Universal_Interpretation (N) = Universal_Integer then
18415 T := Standard_Integer;
18421 Ind : Interp_Index;
18425 Get_First_Interp (N, Ind, It);
18426 while Present (It.Typ) loop
18427 if Is_Discrete_Type (It.Typ) then
18430 and then not Covers (It.Typ, T)
18431 and then not Covers (T, It.Typ)
18433 Error_Msg_N ("ambiguous bounds in discrete range", N);
18441 Get_Next_Interp (Ind, It);
18444 if T = Any_Type then
18445 Error_Msg_N ("discrete type required for range", N);
18446 Set_Etype (N, Any_Type);
18449 elsif T = Universal_Integer then
18450 T := Standard_Integer;
18455 if not Is_Discrete_Type (T) then
18456 Error_Msg_N ("discrete type required for range", N);
18457 Set_Etype (N, Any_Type);
18461 if Nkind (Low_Bound (N)) = N_Attribute_Reference
18462 and then Attribute_Name (Low_Bound (N)) = Name_First
18463 and then Is_Entity_Name (Prefix (Low_Bound (N)))
18464 and then Is_Type (Entity (Prefix (Low_Bound (N))))
18465 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (N))))
18467 -- The type of the index will be the type of the prefix, as long
18468 -- as the upper bound is 'Last of the same type.
18470 Def_Id := Entity (Prefix (Low_Bound (N)));
18472 if Nkind (High_Bound (N)) /= N_Attribute_Reference
18473 or else Attribute_Name (High_Bound (N)) /= Name_Last
18474 or else not Is_Entity_Name (Prefix (High_Bound (N)))
18475 or else Entity (Prefix (High_Bound (N))) /= Def_Id
18482 Process_Range_Expr_In_Decl (R, T, In_Iter_Schm => In_Iter_Schm);
18484 elsif Nkind (N) = N_Subtype_Indication then
18486 -- The index is given by a subtype with a range constraint
18488 T := Base_Type (Entity (Subtype_Mark (N)));
18490 if not Is_Discrete_Type (T) then
18491 Error_Msg_N ("discrete type required for range", N);
18492 Set_Etype (N, Any_Type);
18496 R := Range_Expression (Constraint (N));
18499 Process_Range_Expr_In_Decl
18500 (R, Entity (Subtype_Mark (N)), In_Iter_Schm => In_Iter_Schm);
18502 elsif Nkind (N) = N_Attribute_Reference then
18504 -- Catch beginner's error (use of attribute other than 'Range)
18506 if Attribute_Name (N) /= Name_Range then
18507 Error_Msg_N ("expect attribute ''Range", N);
18508 Set_Etype (N, Any_Type);
18512 -- If the node denotes the range of a type mark, that is also the
18513 -- resulting type, and we do not need to create an Itype for it.
18515 if Is_Entity_Name (Prefix (N))
18516 and then Comes_From_Source (N)
18517 and then Is_Type (Entity (Prefix (N)))
18518 and then Is_Discrete_Type (Entity (Prefix (N)))
18520 Def_Id := Entity (Prefix (N));
18523 Analyze_And_Resolve (N);
18527 -- If none of the above, must be a subtype. We convert this to a
18528 -- range attribute reference because in the case of declared first
18529 -- named subtypes, the types in the range reference can be different
18530 -- from the type of the entity. A range attribute normalizes the
18531 -- reference and obtains the correct types for the bounds.
18533 -- This transformation is in the nature of an expansion, is only
18534 -- done if expansion is active. In particular, it is not done on
18535 -- formal generic types, because we need to retain the name of the
18536 -- original index for instantiation purposes.
18539 if not Is_Entity_Name (N) or else not Is_Type (Entity (N)) then
18540 Error_Msg_N ("invalid subtype mark in discrete range ", N);
18541 Set_Etype (N, Any_Integer);
18545 -- The type mark may be that of an incomplete type. It is only
18546 -- now that we can get the full view, previous analysis does
18547 -- not look specifically for a type mark.
18549 Set_Entity (N, Get_Full_View (Entity (N)));
18550 Set_Etype (N, Entity (N));
18551 Def_Id := Entity (N);
18553 if not Is_Discrete_Type (Def_Id) then
18554 Error_Msg_N ("discrete type required for index", N);
18555 Set_Etype (N, Any_Type);
18560 if Expander_Active then
18562 Make_Attribute_Reference (Sloc (N),
18563 Attribute_Name => Name_Range,
18564 Prefix => Relocate_Node (N)));
18566 -- The original was a subtype mark that does not freeze. This
18567 -- means that the rewritten version must not freeze either.
18569 Set_Must_Not_Freeze (N);
18570 Set_Must_Not_Freeze (Prefix (N));
18571 Analyze_And_Resolve (N);
18575 -- If expander is inactive, type is legal, nothing else to construct
18582 if not Is_Discrete_Type (T) then
18583 Error_Msg_N ("discrete type required for range", N);
18584 Set_Etype (N, Any_Type);
18587 elsif T = Any_Type then
18588 Set_Etype (N, Any_Type);
18592 -- We will now create the appropriate Itype to describe the range, but
18593 -- first a check. If we originally had a subtype, then we just label
18594 -- the range with this subtype. Not only is there no need to construct
18595 -- a new subtype, but it is wrong to do so for two reasons:
18597 -- 1. A legality concern, if we have a subtype, it must not freeze,
18598 -- and the Itype would cause freezing incorrectly
18600 -- 2. An efficiency concern, if we created an Itype, it would not be
18601 -- recognized as the same type for the purposes of eliminating
18602 -- checks in some circumstances.
18604 -- We signal this case by setting the subtype entity in Def_Id
18606 if No (Def_Id) then
18608 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
18609 Set_Etype (Def_Id, Base_Type (T));
18611 if Is_Signed_Integer_Type (T) then
18612 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
18614 elsif Is_Modular_Integer_Type (T) then
18615 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
18618 Set_Ekind (Def_Id, E_Enumeration_Subtype);
18619 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
18620 Set_First_Literal (Def_Id, First_Literal (T));
18623 Set_Size_Info (Def_Id, (T));
18624 Set_RM_Size (Def_Id, RM_Size (T));
18625 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
18627 Set_Scalar_Range (Def_Id, R);
18628 Conditional_Delay (Def_Id, T);
18630 if Nkind (N) = N_Subtype_Indication then
18631 Inherit_Predicate_Flags (Def_Id, Entity (Subtype_Mark (N)));
18634 -- In the subtype indication case, if the immediate parent of the
18635 -- new subtype is non-static, then the subtype we create is non-
18636 -- static, even if its bounds are static.
18638 if Nkind (N) = N_Subtype_Indication
18639 and then not Is_OK_Static_Subtype (Entity (Subtype_Mark (N)))
18641 Set_Is_Non_Static_Subtype (Def_Id);
18645 -- Final step is to label the index with this constructed type
18647 Set_Etype (N, Def_Id);
18650 ------------------------------
18651 -- Modular_Type_Declaration --
18652 ------------------------------
18654 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
18655 Mod_Expr : constant Node_Id := Expression (Def);
18658 procedure Set_Modular_Size (Bits : Int);
18659 -- Sets RM_Size to Bits, and Esize to normal word size above this
18661 ----------------------
18662 -- Set_Modular_Size --
18663 ----------------------
18665 procedure Set_Modular_Size (Bits : Int) is
18667 Set_RM_Size (T, UI_From_Int (Bits));
18672 elsif Bits <= 16 then
18673 Init_Esize (T, 16);
18675 elsif Bits <= 32 then
18676 Init_Esize (T, 32);
18679 Init_Esize (T, System_Max_Binary_Modulus_Power);
18682 if not Non_Binary_Modulus (T) and then Esize (T) = RM_Size (T) then
18683 Set_Is_Known_Valid (T);
18685 end Set_Modular_Size;
18687 -- Start of processing for Modular_Type_Declaration
18690 -- If the mod expression is (exactly) 2 * literal, where literal is
18691 -- 64 or less,then almost certainly the * was meant to be **. Warn.
18693 if Warn_On_Suspicious_Modulus_Value
18694 and then Nkind (Mod_Expr) = N_Op_Multiply
18695 and then Nkind (Left_Opnd (Mod_Expr)) = N_Integer_Literal
18696 and then Intval (Left_Opnd (Mod_Expr)) = Uint_2
18697 and then Nkind (Right_Opnd (Mod_Expr)) = N_Integer_Literal
18698 and then Intval (Right_Opnd (Mod_Expr)) <= Uint_64
18701 ("suspicious MOD value, was '*'* intended'??M?", Mod_Expr);
18704 -- Proceed with analysis of mod expression
18706 Analyze_And_Resolve (Mod_Expr, Any_Integer);
18708 Set_Ekind (T, E_Modular_Integer_Type);
18709 Init_Alignment (T);
18710 Set_Is_Constrained (T);
18712 if not Is_OK_Static_Expression (Mod_Expr) then
18713 Flag_Non_Static_Expr
18714 ("non-static expression used for modular type bound!", Mod_Expr);
18715 M_Val := 2 ** System_Max_Binary_Modulus_Power;
18717 M_Val := Expr_Value (Mod_Expr);
18721 Error_Msg_N ("modulus value must be positive", Mod_Expr);
18722 M_Val := 2 ** System_Max_Binary_Modulus_Power;
18725 if M_Val > 2 ** Standard_Long_Integer_Size then
18726 Check_Restriction (No_Long_Long_Integers, Mod_Expr);
18729 Set_Modulus (T, M_Val);
18731 -- Create bounds for the modular type based on the modulus given in
18732 -- the type declaration and then analyze and resolve those bounds.
18734 Set_Scalar_Range (T,
18735 Make_Range (Sloc (Mod_Expr),
18736 Low_Bound => Make_Integer_Literal (Sloc (Mod_Expr), 0),
18737 High_Bound => Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
18739 -- Properly analyze the literals for the range. We do this manually
18740 -- because we can't go calling Resolve, since we are resolving these
18741 -- bounds with the type, and this type is certainly not complete yet.
18743 Set_Etype (Low_Bound (Scalar_Range (T)), T);
18744 Set_Etype (High_Bound (Scalar_Range (T)), T);
18745 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
18746 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
18748 -- Loop through powers of two to find number of bits required
18750 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
18754 if M_Val = 2 ** Bits then
18755 Set_Modular_Size (Bits);
18760 elsif M_Val < 2 ** Bits then
18761 Check_SPARK_05_Restriction ("modulus should be a power of 2", T);
18762 Set_Non_Binary_Modulus (T);
18764 if Bits > System_Max_Nonbinary_Modulus_Power then
18765 Error_Msg_Uint_1 :=
18766 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
18768 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
18769 Set_Modular_Size (System_Max_Binary_Modulus_Power);
18773 -- In the nonbinary case, set size as per RM 13.3(55)
18775 Set_Modular_Size (Bits);
18782 -- If we fall through, then the size exceed System.Max_Binary_Modulus
18783 -- so we just signal an error and set the maximum size.
18785 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
18786 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
18788 Set_Modular_Size (System_Max_Binary_Modulus_Power);
18789 Init_Alignment (T);
18791 end Modular_Type_Declaration;
18793 --------------------------
18794 -- New_Concatenation_Op --
18795 --------------------------
18797 procedure New_Concatenation_Op (Typ : Entity_Id) is
18798 Loc : constant Source_Ptr := Sloc (Typ);
18801 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
18802 -- Create abbreviated declaration for the formal of a predefined
18803 -- Operator 'Op' of type 'Typ'
18805 --------------------
18806 -- Make_Op_Formal --
18807 --------------------
18809 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
18810 Formal : Entity_Id;
18812 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
18813 Set_Etype (Formal, Typ);
18814 Set_Mechanism (Formal, Default_Mechanism);
18816 end Make_Op_Formal;
18818 -- Start of processing for New_Concatenation_Op
18821 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
18823 Set_Ekind (Op, E_Operator);
18824 Set_Scope (Op, Current_Scope);
18825 Set_Etype (Op, Typ);
18826 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
18827 Set_Is_Immediately_Visible (Op);
18828 Set_Is_Intrinsic_Subprogram (Op);
18829 Set_Has_Completion (Op);
18830 Append_Entity (Op, Current_Scope);
18832 Set_Name_Entity_Id (Name_Op_Concat, Op);
18834 Append_Entity (Make_Op_Formal (Typ, Op), Op);
18835 Append_Entity (Make_Op_Formal (Typ, Op), Op);
18836 end New_Concatenation_Op;
18838 -------------------------
18839 -- OK_For_Limited_Init --
18840 -------------------------
18842 -- ???Check all calls of this, and compare the conditions under which it's
18845 function OK_For_Limited_Init
18847 Exp : Node_Id) return Boolean
18850 return Is_CPP_Constructor_Call (Exp)
18851 or else (Ada_Version >= Ada_2005
18852 and then not Debug_Flag_Dot_L
18853 and then OK_For_Limited_Init_In_05 (Typ, Exp));
18854 end OK_For_Limited_Init;
18856 -------------------------------
18857 -- OK_For_Limited_Init_In_05 --
18858 -------------------------------
18860 function OK_For_Limited_Init_In_05
18862 Exp : Node_Id) return Boolean
18865 -- An object of a limited interface type can be initialized with any
18866 -- expression of a nonlimited descendant type. However this does not
18867 -- apply if this is a view conversion of some other expression. This
18868 -- is checked below.
18870 if Is_Class_Wide_Type (Typ)
18871 and then Is_Limited_Interface (Typ)
18872 and then not Is_Limited_Type (Etype (Exp))
18873 and then Nkind (Exp) /= N_Type_Conversion
18878 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
18879 -- case of limited aggregates (including extension aggregates), and
18880 -- function calls. The function call may have been given in prefixed
18881 -- notation, in which case the original node is an indexed component.
18882 -- If the function is parameterless, the original node was an explicit
18883 -- dereference. The function may also be parameterless, in which case
18884 -- the source node is just an identifier.
18886 -- A branch of a conditional expression may have been removed if the
18887 -- condition is statically known. This happens during expansion, and
18888 -- thus will not happen if previous errors were encountered. The check
18889 -- will have been performed on the chosen branch, which replaces the
18890 -- original conditional expression.
18896 case Nkind (Original_Node (Exp)) is
18897 when N_Aggregate | N_Extension_Aggregate | N_Function_Call | N_Op =>
18900 when N_Identifier =>
18901 return Present (Entity (Original_Node (Exp)))
18902 and then Ekind (Entity (Original_Node (Exp))) = E_Function;
18904 when N_Qualified_Expression =>
18906 OK_For_Limited_Init_In_05
18907 (Typ, Expression (Original_Node (Exp)));
18909 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
18910 -- with a function call, the expander has rewritten the call into an
18911 -- N_Type_Conversion node to force displacement of the pointer to
18912 -- reference the component containing the secondary dispatch table.
18913 -- Otherwise a type conversion is not a legal context.
18914 -- A return statement for a build-in-place function returning a
18915 -- synchronized type also introduces an unchecked conversion.
18917 when N_Type_Conversion |
18918 N_Unchecked_Type_Conversion =>
18919 return not Comes_From_Source (Exp)
18921 OK_For_Limited_Init_In_05
18922 (Typ, Expression (Original_Node (Exp)));
18924 when N_Indexed_Component |
18925 N_Selected_Component |
18926 N_Explicit_Dereference =>
18927 return Nkind (Exp) = N_Function_Call;
18929 -- A use of 'Input is a function call, hence allowed. Normally the
18930 -- attribute will be changed to a call, but the attribute by itself
18931 -- can occur with -gnatc.
18933 when N_Attribute_Reference =>
18934 return Attribute_Name (Original_Node (Exp)) = Name_Input;
18936 -- For a case expression, all dependent expressions must be legal
18938 when N_Case_Expression =>
18943 Alt := First (Alternatives (Original_Node (Exp)));
18944 while Present (Alt) loop
18945 if not OK_For_Limited_Init_In_05 (Typ, Expression (Alt)) then
18955 -- For an if expression, all dependent expressions must be legal
18957 when N_If_Expression =>
18959 Then_Expr : constant Node_Id :=
18960 Next (First (Expressions (Original_Node (Exp))));
18961 Else_Expr : constant Node_Id := Next (Then_Expr);
18963 return OK_For_Limited_Init_In_05 (Typ, Then_Expr)
18965 OK_For_Limited_Init_In_05 (Typ, Else_Expr);
18971 end OK_For_Limited_Init_In_05;
18973 -------------------------------------------
18974 -- Ordinary_Fixed_Point_Type_Declaration --
18975 -------------------------------------------
18977 procedure Ordinary_Fixed_Point_Type_Declaration
18981 Loc : constant Source_Ptr := Sloc (Def);
18982 Delta_Expr : constant Node_Id := Delta_Expression (Def);
18983 RRS : constant Node_Id := Real_Range_Specification (Def);
18984 Implicit_Base : Entity_Id;
18991 Check_Restriction (No_Fixed_Point, Def);
18993 -- Create implicit base type
18996 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
18997 Set_Etype (Implicit_Base, Implicit_Base);
18999 -- Analyze and process delta expression
19001 Analyze_And_Resolve (Delta_Expr, Any_Real);
19003 Check_Delta_Expression (Delta_Expr);
19004 Delta_Val := Expr_Value_R (Delta_Expr);
19006 Set_Delta_Value (Implicit_Base, Delta_Val);
19008 -- Compute default small from given delta, which is the largest power
19009 -- of two that does not exceed the given delta value.
19019 if Delta_Val < Ureal_1 then
19020 while Delta_Val < Tmp loop
19021 Tmp := Tmp / Ureal_2;
19022 Scale := Scale + 1;
19027 Tmp := Tmp * Ureal_2;
19028 exit when Tmp > Delta_Val;
19029 Scale := Scale - 1;
19033 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
19036 Set_Small_Value (Implicit_Base, Small_Val);
19038 -- If no range was given, set a dummy range
19040 if RRS <= Empty_Or_Error then
19041 Low_Val := -Small_Val;
19042 High_Val := Small_Val;
19044 -- Otherwise analyze and process given range
19048 Low : constant Node_Id := Low_Bound (RRS);
19049 High : constant Node_Id := High_Bound (RRS);
19052 Analyze_And_Resolve (Low, Any_Real);
19053 Analyze_And_Resolve (High, Any_Real);
19054 Check_Real_Bound (Low);
19055 Check_Real_Bound (High);
19057 -- Obtain and set the range
19059 Low_Val := Expr_Value_R (Low);
19060 High_Val := Expr_Value_R (High);
19062 if Low_Val > High_Val then
19063 Error_Msg_NE ("??fixed point type& has null range", Def, T);
19068 -- The range for both the implicit base and the declared first subtype
19069 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
19070 -- set a temporary range in place. Note that the bounds of the base
19071 -- type will be widened to be symmetrical and to fill the available
19072 -- bits when the type is frozen.
19074 -- We could do this with all discrete types, and probably should, but
19075 -- we absolutely have to do it for fixed-point, since the end-points
19076 -- of the range and the size are determined by the small value, which
19077 -- could be reset before the freeze point.
19079 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
19080 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
19082 -- Complete definition of first subtype. The inheritance of the rep item
19083 -- chain ensures that SPARK-related pragmas are not clobbered when the
19084 -- ordinary fixed point type acts as a full view of a private type.
19086 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
19087 Set_Etype (T, Implicit_Base);
19088 Init_Size_Align (T);
19089 Inherit_Rep_Item_Chain (T, Implicit_Base);
19090 Set_Small_Value (T, Small_Val);
19091 Set_Delta_Value (T, Delta_Val);
19092 Set_Is_Constrained (T);
19093 end Ordinary_Fixed_Point_Type_Declaration;
19095 ----------------------------------
19096 -- Preanalyze_Assert_Expression --
19097 ----------------------------------
19099 procedure Preanalyze_Assert_Expression (N : Node_Id; T : Entity_Id) is
19101 In_Assertion_Expr := In_Assertion_Expr + 1;
19102 Preanalyze_Spec_Expression (N, T);
19103 In_Assertion_Expr := In_Assertion_Expr - 1;
19104 end Preanalyze_Assert_Expression;
19106 -----------------------------------
19107 -- Preanalyze_Default_Expression --
19108 -----------------------------------
19110 procedure Preanalyze_Default_Expression (N : Node_Id; T : Entity_Id) is
19111 Save_In_Default_Expr : constant Boolean := In_Default_Expr;
19113 In_Default_Expr := True;
19114 Preanalyze_Spec_Expression (N, T);
19115 In_Default_Expr := Save_In_Default_Expr;
19116 end Preanalyze_Default_Expression;
19118 --------------------------------
19119 -- Preanalyze_Spec_Expression --
19120 --------------------------------
19122 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
19123 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
19125 In_Spec_Expression := True;
19126 Preanalyze_And_Resolve (N, T);
19127 In_Spec_Expression := Save_In_Spec_Expression;
19128 end Preanalyze_Spec_Expression;
19130 ----------------------------------------
19131 -- Prepare_Private_Subtype_Completion --
19132 ----------------------------------------
19134 procedure Prepare_Private_Subtype_Completion
19136 Related_Nod : Node_Id)
19138 Id_B : constant Entity_Id := Base_Type (Id);
19139 Full_B : Entity_Id := Full_View (Id_B);
19143 if Present (Full_B) then
19145 -- Get to the underlying full view if necessary
19147 if Is_Private_Type (Full_B)
19148 and then Present (Underlying_Full_View (Full_B))
19150 Full_B := Underlying_Full_View (Full_B);
19153 -- The Base_Type is already completed, we can complete the subtype
19154 -- now. We have to create a new entity with the same name, Thus we
19155 -- can't use Create_Itype.
19157 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
19158 Set_Is_Itype (Full);
19159 Set_Associated_Node_For_Itype (Full, Related_Nod);
19160 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
19163 -- The parent subtype may be private, but the base might not, in some
19164 -- nested instances. In that case, the subtype does not need to be
19165 -- exchanged. It would still be nice to make private subtypes and their
19166 -- bases consistent at all times ???
19168 if Is_Private_Type (Id_B) then
19169 Append_Elmt (Id, Private_Dependents (Id_B));
19171 end Prepare_Private_Subtype_Completion;
19173 ---------------------------
19174 -- Process_Discriminants --
19175 ---------------------------
19177 procedure Process_Discriminants
19179 Prev : Entity_Id := Empty)
19181 Elist : constant Elist_Id := New_Elmt_List;
19184 Discr_Number : Uint;
19185 Discr_Type : Entity_Id;
19186 Default_Present : Boolean := False;
19187 Default_Not_Present : Boolean := False;
19190 -- A composite type other than an array type can have discriminants.
19191 -- On entry, the current scope is the composite type.
19193 -- The discriminants are initially entered into the scope of the type
19194 -- via Enter_Name with the default Ekind of E_Void to prevent premature
19195 -- use, as explained at the end of this procedure.
19197 Discr := First (Discriminant_Specifications (N));
19198 while Present (Discr) loop
19199 Enter_Name (Defining_Identifier (Discr));
19201 -- For navigation purposes we add a reference to the discriminant
19202 -- in the entity for the type. If the current declaration is a
19203 -- completion, place references on the partial view. Otherwise the
19204 -- type is the current scope.
19206 if Present (Prev) then
19208 -- The references go on the partial view, if present. If the
19209 -- partial view has discriminants, the references have been
19210 -- generated already.
19212 if not Has_Discriminants (Prev) then
19213 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
19217 (Current_Scope, Defining_Identifier (Discr), 'd');
19220 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
19221 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
19223 -- Ada 2005 (AI-254)
19225 if Present (Access_To_Subprogram_Definition
19226 (Discriminant_Type (Discr)))
19227 and then Protected_Present (Access_To_Subprogram_Definition
19228 (Discriminant_Type (Discr)))
19231 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
19235 Find_Type (Discriminant_Type (Discr));
19236 Discr_Type := Etype (Discriminant_Type (Discr));
19238 if Error_Posted (Discriminant_Type (Discr)) then
19239 Discr_Type := Any_Type;
19243 -- Handling of discriminants that are access types
19245 if Is_Access_Type (Discr_Type) then
19247 -- Ada 2005 (AI-230): Access discriminant allowed in non-
19248 -- limited record types
19250 if Ada_Version < Ada_2005 then
19251 Check_Access_Discriminant_Requires_Limited
19252 (Discr, Discriminant_Type (Discr));
19255 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
19257 ("(Ada 83) access discriminant not allowed", Discr);
19260 -- If not access type, must be a discrete type
19262 elsif not Is_Discrete_Type (Discr_Type) then
19264 ("discriminants must have a discrete or access type",
19265 Discriminant_Type (Discr));
19268 Set_Etype (Defining_Identifier (Discr), Discr_Type);
19270 -- If a discriminant specification includes the assignment compound
19271 -- delimiter followed by an expression, the expression is the default
19272 -- expression of the discriminant; the default expression must be of
19273 -- the type of the discriminant. (RM 3.7.1) Since this expression is
19274 -- a default expression, we do the special preanalysis, since this
19275 -- expression does not freeze (see section "Handling of Default and
19276 -- Per-Object Expressions" in spec of package Sem).
19278 if Present (Expression (Discr)) then
19279 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
19283 if Nkind (N) = N_Formal_Type_Declaration then
19285 ("discriminant defaults not allowed for formal type",
19286 Expression (Discr));
19288 -- Flag an error for a tagged type with defaulted discriminants,
19289 -- excluding limited tagged types when compiling for Ada 2012
19290 -- (see AI05-0214).
19292 elsif Is_Tagged_Type (Current_Scope)
19293 and then (not Is_Limited_Type (Current_Scope)
19294 or else Ada_Version < Ada_2012)
19295 and then Comes_From_Source (N)
19297 -- Note: see similar test in Check_Or_Process_Discriminants, to
19298 -- handle the (illegal) case of the completion of an untagged
19299 -- view with discriminants with defaults by a tagged full view.
19300 -- We skip the check if Discr does not come from source, to
19301 -- account for the case of an untagged derived type providing
19302 -- defaults for a renamed discriminant from a private untagged
19303 -- ancestor with a tagged full view (ACATS B460006).
19305 if Ada_Version >= Ada_2012 then
19307 ("discriminants of nonlimited tagged type cannot have"
19309 Expression (Discr));
19312 ("discriminants of tagged type cannot have defaults",
19313 Expression (Discr));
19317 Default_Present := True;
19318 Append_Elmt (Expression (Discr), Elist);
19320 -- Tag the defining identifiers for the discriminants with
19321 -- their corresponding default expressions from the tree.
19323 Set_Discriminant_Default_Value
19324 (Defining_Identifier (Discr), Expression (Discr));
19327 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag
19328 -- gets set unless we can be sure that no range check is required.
19330 if (GNATprove_Mode or not Expander_Active)
19333 (Expression (Discr), Discr_Type, Assume_Valid => True)
19335 Set_Do_Range_Check (Expression (Discr));
19338 -- No default discriminant value given
19341 Default_Not_Present := True;
19344 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
19345 -- Discr_Type but with the null-exclusion attribute
19347 if Ada_Version >= Ada_2005 then
19349 -- Ada 2005 (AI-231): Static checks
19351 if Can_Never_Be_Null (Discr_Type) then
19352 Null_Exclusion_Static_Checks (Discr);
19354 elsif Is_Access_Type (Discr_Type)
19355 and then Null_Exclusion_Present (Discr)
19357 -- No need to check itypes because in their case this check
19358 -- was done at their point of creation
19360 and then not Is_Itype (Discr_Type)
19362 if Can_Never_Be_Null (Discr_Type) then
19364 ("`NOT NULL` not allowed (& already excludes null)",
19369 Set_Etype (Defining_Identifier (Discr),
19370 Create_Null_Excluding_Itype
19372 Related_Nod => Discr));
19374 -- Check for improper null exclusion if the type is otherwise
19375 -- legal for a discriminant.
19377 elsif Null_Exclusion_Present (Discr)
19378 and then Is_Discrete_Type (Discr_Type)
19381 ("null exclusion can only apply to an access type", Discr);
19384 -- Ada 2005 (AI-402): access discriminants of nonlimited types
19385 -- can't have defaults. Synchronized types, or types that are
19386 -- explicitly limited are fine, but special tests apply to derived
19387 -- types in generics: in a generic body we have to assume the
19388 -- worst, and therefore defaults are not allowed if the parent is
19389 -- a generic formal private type (see ACATS B370001).
19391 if Is_Access_Type (Discr_Type) and then Default_Present then
19392 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
19393 or else Is_Limited_Record (Current_Scope)
19394 or else Is_Concurrent_Type (Current_Scope)
19395 or else Is_Concurrent_Record_Type (Current_Scope)
19396 or else Ekind (Current_Scope) = E_Limited_Private_Type
19398 if not Is_Derived_Type (Current_Scope)
19399 or else not Is_Generic_Type (Etype (Current_Scope))
19400 or else not In_Package_Body (Scope (Etype (Current_Scope)))
19401 or else Limited_Present
19402 (Type_Definition (Parent (Current_Scope)))
19408 ("access discriminants of nonlimited types cannot "
19409 & "have defaults", Expression (Discr));
19412 elsif Present (Expression (Discr)) then
19414 ("(Ada 2005) access discriminants of nonlimited types "
19415 & "cannot have defaults", Expression (Discr));
19420 -- A discriminant cannot be effectively volatile (SPARK RM 7.1.3(6)).
19421 -- This check is relevant only when SPARK_Mode is on as it is not a
19422 -- standard Ada legality rule.
19425 and then Is_Effectively_Volatile (Defining_Identifier (Discr))
19427 Error_Msg_N ("discriminant cannot be volatile", Discr);
19433 -- An element list consisting of the default expressions of the
19434 -- discriminants is constructed in the above loop and used to set
19435 -- the Discriminant_Constraint attribute for the type. If an object
19436 -- is declared of this (record or task) type without any explicit
19437 -- discriminant constraint given, this element list will form the
19438 -- actual parameters for the corresponding initialization procedure
19441 Set_Discriminant_Constraint (Current_Scope, Elist);
19442 Set_Stored_Constraint (Current_Scope, No_Elist);
19444 -- Default expressions must be provided either for all or for none
19445 -- of the discriminants of a discriminant part. (RM 3.7.1)
19447 if Default_Present and then Default_Not_Present then
19449 ("incomplete specification of defaults for discriminants", N);
19452 -- The use of the name of a discriminant is not allowed in default
19453 -- expressions of a discriminant part if the specification of the
19454 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
19456 -- To detect this, the discriminant names are entered initially with an
19457 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
19458 -- attempt to use a void entity (for example in an expression that is
19459 -- type-checked) produces the error message: premature usage. Now after
19460 -- completing the semantic analysis of the discriminant part, we can set
19461 -- the Ekind of all the discriminants appropriately.
19463 Discr := First (Discriminant_Specifications (N));
19464 Discr_Number := Uint_1;
19465 while Present (Discr) loop
19466 Id := Defining_Identifier (Discr);
19467 Set_Ekind (Id, E_Discriminant);
19468 Init_Component_Location (Id);
19470 Set_Discriminant_Number (Id, Discr_Number);
19472 -- Make sure this is always set, even in illegal programs
19474 Set_Corresponding_Discriminant (Id, Empty);
19476 -- Initialize the Original_Record_Component to the entity itself.
19477 -- Inherit_Components will propagate the right value to
19478 -- discriminants in derived record types.
19480 Set_Original_Record_Component (Id, Id);
19482 -- Create the discriminal for the discriminant
19484 Build_Discriminal (Id);
19487 Discr_Number := Discr_Number + 1;
19490 Set_Has_Discriminants (Current_Scope);
19491 end Process_Discriminants;
19493 -----------------------
19494 -- Process_Full_View --
19495 -----------------------
19497 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
19498 procedure Collect_Implemented_Interfaces
19500 Ifaces : Elist_Id);
19501 -- Ada 2005: Gather all the interfaces that Typ directly or
19502 -- inherently implements. Duplicate entries are not added to
19503 -- the list Ifaces.
19505 ------------------------------------
19506 -- Collect_Implemented_Interfaces --
19507 ------------------------------------
19509 procedure Collect_Implemented_Interfaces
19514 Iface_Elmt : Elmt_Id;
19517 -- Abstract interfaces are only associated with tagged record types
19519 if not Is_Tagged_Type (Typ) or else not Is_Record_Type (Typ) then
19523 -- Recursively climb to the ancestors
19525 if Etype (Typ) /= Typ
19527 -- Protect the frontend against wrong cyclic declarations like:
19529 -- type B is new A with private;
19530 -- type C is new A with private;
19532 -- type B is new C with null record;
19533 -- type C is new B with null record;
19535 and then Etype (Typ) /= Priv_T
19536 and then Etype (Typ) /= Full_T
19538 -- Keep separate the management of private type declarations
19540 if Ekind (Typ) = E_Record_Type_With_Private then
19542 -- Handle the following illegal usage:
19543 -- type Private_Type is tagged private;
19545 -- type Private_Type is new Type_Implementing_Iface;
19547 if Present (Full_View (Typ))
19548 and then Etype (Typ) /= Full_View (Typ)
19550 if Is_Interface (Etype (Typ)) then
19551 Append_Unique_Elmt (Etype (Typ), Ifaces);
19554 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
19557 -- Non-private types
19560 if Is_Interface (Etype (Typ)) then
19561 Append_Unique_Elmt (Etype (Typ), Ifaces);
19564 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
19568 -- Handle entities in the list of abstract interfaces
19570 if Present (Interfaces (Typ)) then
19571 Iface_Elmt := First_Elmt (Interfaces (Typ));
19572 while Present (Iface_Elmt) loop
19573 Iface := Node (Iface_Elmt);
19575 pragma Assert (Is_Interface (Iface));
19577 if not Contain_Interface (Iface, Ifaces) then
19578 Append_Elmt (Iface, Ifaces);
19579 Collect_Implemented_Interfaces (Iface, Ifaces);
19582 Next_Elmt (Iface_Elmt);
19585 end Collect_Implemented_Interfaces;
19589 Full_Indic : Node_Id;
19590 Full_Parent : Entity_Id;
19591 Priv_Parent : Entity_Id;
19593 -- Start of processing for Process_Full_View
19596 -- First some sanity checks that must be done after semantic
19597 -- decoration of the full view and thus cannot be placed with other
19598 -- similar checks in Find_Type_Name
19600 if not Is_Limited_Type (Priv_T)
19601 and then (Is_Limited_Type (Full_T)
19602 or else Is_Limited_Composite (Full_T))
19604 if In_Instance then
19608 ("completion of nonlimited type cannot be limited", Full_T);
19609 Explain_Limited_Type (Full_T, Full_T);
19612 elsif Is_Abstract_Type (Full_T)
19613 and then not Is_Abstract_Type (Priv_T)
19616 ("completion of nonabstract type cannot be abstract", Full_T);
19618 elsif Is_Tagged_Type (Priv_T)
19619 and then Is_Limited_Type (Priv_T)
19620 and then not Is_Limited_Type (Full_T)
19622 -- If pragma CPP_Class was applied to the private declaration
19623 -- propagate the limitedness to the full-view
19625 if Is_CPP_Class (Priv_T) then
19626 Set_Is_Limited_Record (Full_T);
19628 -- GNAT allow its own definition of Limited_Controlled to disobey
19629 -- this rule in order in ease the implementation. This test is safe
19630 -- because Root_Controlled is defined in a child of System that
19631 -- normal programs are not supposed to use.
19633 elsif Is_RTE (Etype (Full_T), RE_Root_Controlled) then
19634 Set_Is_Limited_Composite (Full_T);
19637 ("completion of limited tagged type must be limited", Full_T);
19640 elsif Is_Generic_Type (Priv_T) then
19641 Error_Msg_N ("generic type cannot have a completion", Full_T);
19644 -- Check that ancestor interfaces of private and full views are
19645 -- consistent. We omit this check for synchronized types because
19646 -- they are performed on the corresponding record type when frozen.
19648 if Ada_Version >= Ada_2005
19649 and then Is_Tagged_Type (Priv_T)
19650 and then Is_Tagged_Type (Full_T)
19651 and then not Is_Concurrent_Type (Full_T)
19655 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
19656 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
19659 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
19660 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
19662 -- Ada 2005 (AI-251): The partial view shall be a descendant of
19663 -- an interface type if and only if the full type is descendant
19664 -- of the interface type (AARM 7.3 (7.3/2)).
19666 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
19668 if Present (Iface) then
19670 ("interface in partial view& not implemented by full type "
19671 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
19674 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
19676 if Present (Iface) then
19678 ("interface & not implemented by partial view "
19679 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
19684 if Is_Tagged_Type (Priv_T)
19685 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19686 and then Is_Derived_Type (Full_T)
19688 Priv_Parent := Etype (Priv_T);
19690 -- The full view of a private extension may have been transformed
19691 -- into an unconstrained derived type declaration and a subtype
19692 -- declaration (see build_derived_record_type for details).
19694 if Nkind (N) = N_Subtype_Declaration then
19695 Full_Indic := Subtype_Indication (N);
19696 Full_Parent := Etype (Base_Type (Full_T));
19698 Full_Indic := Subtype_Indication (Type_Definition (N));
19699 Full_Parent := Etype (Full_T);
19702 -- Check that the parent type of the full type is a descendant of
19703 -- the ancestor subtype given in the private extension. If either
19704 -- entity has an Etype equal to Any_Type then we had some previous
19705 -- error situation [7.3(8)].
19707 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
19710 -- Ada 2005 (AI-251): Interfaces in the full type can be given in
19711 -- any order. Therefore we don't have to check that its parent must
19712 -- be a descendant of the parent of the private type declaration.
19714 elsif Is_Interface (Priv_Parent)
19715 and then Is_Interface (Full_Parent)
19719 -- Ada 2005 (AI-251): If the parent of the private type declaration
19720 -- is an interface there is no need to check that it is an ancestor
19721 -- of the associated full type declaration. The required tests for
19722 -- this case are performed by Build_Derived_Record_Type.
19724 elsif not Is_Interface (Base_Type (Priv_Parent))
19725 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
19728 ("parent of full type must descend from parent of private "
19729 & "extension", Full_Indic);
19731 -- First check a formal restriction, and then proceed with checking
19732 -- Ada rules. Since the formal restriction is not a serious error, we
19733 -- don't prevent further error detection for this check, hence the
19737 -- In formal mode, when completing a private extension the type
19738 -- named in the private part must be exactly the same as that
19739 -- named in the visible part.
19741 if Priv_Parent /= Full_Parent then
19742 Error_Msg_Name_1 := Chars (Priv_Parent);
19743 Check_SPARK_05_Restriction ("% expected", Full_Indic);
19746 -- Check the rules of 7.3(10): if the private extension inherits
19747 -- known discriminants, then the full type must also inherit those
19748 -- discriminants from the same (ancestor) type, and the parent
19749 -- subtype of the full type must be constrained if and only if
19750 -- the ancestor subtype of the private extension is constrained.
19752 if No (Discriminant_Specifications (Parent (Priv_T)))
19753 and then not Has_Unknown_Discriminants (Priv_T)
19754 and then Has_Discriminants (Base_Type (Priv_Parent))
19757 Priv_Indic : constant Node_Id :=
19758 Subtype_Indication (Parent (Priv_T));
19760 Priv_Constr : constant Boolean :=
19761 Is_Constrained (Priv_Parent)
19763 Nkind (Priv_Indic) = N_Subtype_Indication
19765 Is_Constrained (Entity (Priv_Indic));
19767 Full_Constr : constant Boolean :=
19768 Is_Constrained (Full_Parent)
19770 Nkind (Full_Indic) = N_Subtype_Indication
19772 Is_Constrained (Entity (Full_Indic));
19774 Priv_Discr : Entity_Id;
19775 Full_Discr : Entity_Id;
19778 Priv_Discr := First_Discriminant (Priv_Parent);
19779 Full_Discr := First_Discriminant (Full_Parent);
19780 while Present (Priv_Discr) and then Present (Full_Discr) loop
19781 if Original_Record_Component (Priv_Discr) =
19782 Original_Record_Component (Full_Discr)
19784 Corresponding_Discriminant (Priv_Discr) =
19785 Corresponding_Discriminant (Full_Discr)
19792 Next_Discriminant (Priv_Discr);
19793 Next_Discriminant (Full_Discr);
19796 if Present (Priv_Discr) or else Present (Full_Discr) then
19798 ("full view must inherit discriminants of the parent "
19799 & "type used in the private extension", Full_Indic);
19801 elsif Priv_Constr and then not Full_Constr then
19803 ("parent subtype of full type must be constrained",
19806 elsif Full_Constr and then not Priv_Constr then
19808 ("parent subtype of full type must be unconstrained",
19813 -- Check the rules of 7.3(12): if a partial view has neither
19814 -- known or unknown discriminants, then the full type
19815 -- declaration shall define a definite subtype.
19817 elsif not Has_Unknown_Discriminants (Priv_T)
19818 and then not Has_Discriminants (Priv_T)
19819 and then not Is_Constrained (Full_T)
19822 ("full view must define a constrained type if partial view "
19823 & "has no discriminants", Full_T);
19826 -- ??????? Do we implement the following properly ?????
19827 -- If the ancestor subtype of a private extension has constrained
19828 -- discriminants, then the parent subtype of the full view shall
19829 -- impose a statically matching constraint on those discriminants
19834 -- For untagged types, verify that a type without discriminants is
19835 -- not completed with an unconstrained type. A separate error message
19836 -- is produced if the full type has defaulted discriminants.
19838 if Is_Definite_Subtype (Priv_T)
19839 and then not Is_Definite_Subtype (Full_T)
19841 Error_Msg_Sloc := Sloc (Parent (Priv_T));
19843 ("full view of& not compatible with declaration#",
19846 if not Is_Tagged_Type (Full_T) then
19848 ("\one is constrained, the other unconstrained", Full_T);
19853 -- AI-419: verify that the use of "limited" is consistent
19856 Orig_Decl : constant Node_Id := Original_Node (N);
19859 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19860 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
19862 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
19864 if not Limited_Present (Parent (Priv_T))
19865 and then not Synchronized_Present (Parent (Priv_T))
19866 and then Limited_Present (Type_Definition (Orig_Decl))
19869 ("full view of non-limited extension cannot be limited", N);
19871 -- Conversely, if the partial view carries the limited keyword,
19872 -- the full view must as well, even if it may be redundant.
19874 elsif Limited_Present (Parent (Priv_T))
19875 and then not Limited_Present (Type_Definition (Orig_Decl))
19878 ("full view of limited extension must be explicitly limited",
19884 -- Ada 2005 (AI-443): A synchronized private extension must be
19885 -- completed by a task or protected type.
19887 if Ada_Version >= Ada_2005
19888 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19889 and then Synchronized_Present (Parent (Priv_T))
19890 and then not Is_Concurrent_Type (Full_T)
19892 Error_Msg_N ("full view of synchronized extension must " &
19893 "be synchronized type", N);
19896 -- Ada 2005 AI-363: if the full view has discriminants with
19897 -- defaults, it is illegal to declare constrained access subtypes
19898 -- whose designated type is the current type. This allows objects
19899 -- of the type that are declared in the heap to be unconstrained.
19901 if not Has_Unknown_Discriminants (Priv_T)
19902 and then not Has_Discriminants (Priv_T)
19903 and then Has_Discriminants (Full_T)
19905 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
19907 Set_Has_Constrained_Partial_View (Full_T);
19908 Set_Has_Constrained_Partial_View (Priv_T);
19911 -- Create a full declaration for all its subtypes recorded in
19912 -- Private_Dependents and swap them similarly to the base type. These
19913 -- are subtypes that have been define before the full declaration of
19914 -- the private type. We also swap the entry in Private_Dependents list
19915 -- so we can properly restore the private view on exit from the scope.
19918 Priv_Elmt : Elmt_Id;
19919 Priv_Scop : Entity_Id;
19924 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
19925 while Present (Priv_Elmt) loop
19926 Priv := Node (Priv_Elmt);
19927 Priv_Scop := Scope (Priv);
19929 if Ekind_In (Priv, E_Private_Subtype,
19930 E_Limited_Private_Subtype,
19931 E_Record_Subtype_With_Private)
19933 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
19934 Set_Is_Itype (Full);
19935 Set_Parent (Full, Parent (Priv));
19936 Set_Associated_Node_For_Itype (Full, N);
19938 -- Now we need to complete the private subtype, but since the
19939 -- base type has already been swapped, we must also swap the
19940 -- subtypes (and thus, reverse the arguments in the call to
19941 -- Complete_Private_Subtype). Also note that we may need to
19942 -- re-establish the scope of the private subtype.
19944 Copy_And_Swap (Priv, Full);
19946 if not In_Open_Scopes (Priv_Scop) then
19947 Push_Scope (Priv_Scop);
19950 -- Reset Priv_Scop to Empty to indicate no scope was pushed
19952 Priv_Scop := Empty;
19955 Complete_Private_Subtype (Full, Priv, Full_T, N);
19957 if Present (Priv_Scop) then
19961 Replace_Elmt (Priv_Elmt, Full);
19964 Next_Elmt (Priv_Elmt);
19968 -- If the private view was tagged, copy the new primitive operations
19969 -- from the private view to the full view.
19971 if Is_Tagged_Type (Full_T) then
19973 Disp_Typ : Entity_Id;
19974 Full_List : Elist_Id;
19976 Prim_Elmt : Elmt_Id;
19977 Priv_List : Elist_Id;
19981 L : Elist_Id) return Boolean;
19982 -- Determine whether list L contains element E
19990 L : Elist_Id) return Boolean
19992 List_Elmt : Elmt_Id;
19995 List_Elmt := First_Elmt (L);
19996 while Present (List_Elmt) loop
19997 if Node (List_Elmt) = E then
20001 Next_Elmt (List_Elmt);
20007 -- Start of processing
20010 if Is_Tagged_Type (Priv_T) then
20011 Priv_List := Primitive_Operations (Priv_T);
20012 Prim_Elmt := First_Elmt (Priv_List);
20014 -- In the case of a concurrent type completing a private tagged
20015 -- type, primitives may have been declared in between the two
20016 -- views. These subprograms need to be wrapped the same way
20017 -- entries and protected procedures are handled because they
20018 -- cannot be directly shared by the two views.
20020 if Is_Concurrent_Type (Full_T) then
20022 Conc_Typ : constant Entity_Id :=
20023 Corresponding_Record_Type (Full_T);
20024 Curr_Nod : Node_Id := Parent (Conc_Typ);
20025 Wrap_Spec : Node_Id;
20028 while Present (Prim_Elmt) loop
20029 Prim := Node (Prim_Elmt);
20031 if Comes_From_Source (Prim)
20032 and then not Is_Abstract_Subprogram (Prim)
20035 Make_Subprogram_Declaration (Sloc (Prim),
20039 Obj_Typ => Conc_Typ,
20041 Parameter_Specifications
20044 Insert_After (Curr_Nod, Wrap_Spec);
20045 Curr_Nod := Wrap_Spec;
20047 Analyze (Wrap_Spec);
20049 -- Remove the wrapper from visibility to avoid
20050 -- spurious conflict with the wrapped entity.
20052 Set_Is_Immediately_Visible
20053 (Defining_Entity (Specification (Wrap_Spec)),
20057 Next_Elmt (Prim_Elmt);
20063 -- For non-concurrent types, transfer explicit primitives, but
20064 -- omit those inherited from the parent of the private view
20065 -- since they will be re-inherited later on.
20068 Full_List := Primitive_Operations (Full_T);
20070 while Present (Prim_Elmt) loop
20071 Prim := Node (Prim_Elmt);
20073 if Comes_From_Source (Prim)
20074 and then not Contains (Prim, Full_List)
20076 Append_Elmt (Prim, Full_List);
20079 Next_Elmt (Prim_Elmt);
20083 -- Untagged private view
20086 Full_List := Primitive_Operations (Full_T);
20088 -- In this case the partial view is untagged, so here we locate
20089 -- all of the earlier primitives that need to be treated as
20090 -- dispatching (those that appear between the two views). Note
20091 -- that these additional operations must all be new operations
20092 -- (any earlier operations that override inherited operations
20093 -- of the full view will already have been inserted in the
20094 -- primitives list, marked by Check_Operation_From_Private_View
20095 -- as dispatching. Note that implicit "/=" operators are
20096 -- excluded from being added to the primitives list since they
20097 -- shouldn't be treated as dispatching (tagged "/=" is handled
20100 Prim := Next_Entity (Full_T);
20101 while Present (Prim) and then Prim /= Priv_T loop
20102 if Ekind_In (Prim, E_Procedure, E_Function) then
20103 Disp_Typ := Find_Dispatching_Type (Prim);
20105 if Disp_Typ = Full_T
20106 and then (Chars (Prim) /= Name_Op_Ne
20107 or else Comes_From_Source (Prim))
20109 Check_Controlling_Formals (Full_T, Prim);
20111 if not Is_Dispatching_Operation (Prim) then
20112 Append_Elmt (Prim, Full_List);
20113 Set_Is_Dispatching_Operation (Prim, True);
20114 Set_DT_Position_Value (Prim, No_Uint);
20117 elsif Is_Dispatching_Operation (Prim)
20118 and then Disp_Typ /= Full_T
20121 -- Verify that it is not otherwise controlled by a
20122 -- formal or a return value of type T.
20124 Check_Controlling_Formals (Disp_Typ, Prim);
20128 Next_Entity (Prim);
20132 -- For the tagged case, the two views can share the same primitive
20133 -- operations list and the same class-wide type. Update attributes
20134 -- of the class-wide type which depend on the full declaration.
20136 if Is_Tagged_Type (Priv_T) then
20137 Set_Direct_Primitive_Operations (Priv_T, Full_List);
20138 Set_Class_Wide_Type
20139 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
20141 Propagate_Concurrent_Flags (Class_Wide_Type (Priv_T), Full_T);
20146 -- Ada 2005 AI 161: Check preelaborable initialization consistency
20148 if Known_To_Have_Preelab_Init (Priv_T) then
20150 -- Case where there is a pragma Preelaborable_Initialization. We
20151 -- always allow this in predefined units, which is cheating a bit,
20152 -- but it means we don't have to struggle to meet the requirements in
20153 -- the RM for having Preelaborable Initialization. Otherwise we
20154 -- require that the type meets the RM rules. But we can't check that
20155 -- yet, because of the rule about overriding Initialize, so we simply
20156 -- set a flag that will be checked at freeze time.
20158 if not In_Predefined_Unit (Full_T) then
20159 Set_Must_Have_Preelab_Init (Full_T);
20163 -- If pragma CPP_Class was applied to the private type declaration,
20164 -- propagate it now to the full type declaration.
20166 if Is_CPP_Class (Priv_T) then
20167 Set_Is_CPP_Class (Full_T);
20168 Set_Convention (Full_T, Convention_CPP);
20170 -- Check that components of imported CPP types do not have default
20173 Check_CPP_Type_Has_No_Defaults (Full_T);
20176 -- If the private view has user specified stream attributes, then so has
20179 -- Why the test, how could these flags be already set in Full_T ???
20181 if Has_Specified_Stream_Read (Priv_T) then
20182 Set_Has_Specified_Stream_Read (Full_T);
20185 if Has_Specified_Stream_Write (Priv_T) then
20186 Set_Has_Specified_Stream_Write (Full_T);
20189 if Has_Specified_Stream_Input (Priv_T) then
20190 Set_Has_Specified_Stream_Input (Full_T);
20193 if Has_Specified_Stream_Output (Priv_T) then
20194 Set_Has_Specified_Stream_Output (Full_T);
20197 -- Propagate the attributes related to pragma Default_Initial_Condition
20198 -- from the private to the full view. Note that both flags are mutually
20201 if Has_Default_Init_Cond (Priv_T)
20202 or else Has_Inherited_Default_Init_Cond (Priv_T)
20204 Propagate_Default_Init_Cond_Attributes
20205 (From_Typ => Priv_T,
20207 Private_To_Full_View => True);
20209 -- In the case where the full view is derived from another private type,
20210 -- the attributes related to pragma Default_Initial_Condition must be
20211 -- propagated from the full to the private view to maintain consistency
20215 -- type Parent_Typ is private
20216 -- with Default_Initial_Condition ...;
20218 -- type Parent_Typ is ...;
20221 -- with Pack; use Pack;
20222 -- package Pack_2 is
20223 -- type Deriv_Typ is private; -- must inherit
20225 -- type Deriv_Typ is new Parent_Typ; -- must inherit
20228 elsif Has_Default_Init_Cond (Full_T)
20229 or else Has_Inherited_Default_Init_Cond (Full_T)
20231 Propagate_Default_Init_Cond_Attributes
20232 (From_Typ => Full_T,
20234 Private_To_Full_View => True);
20237 if Is_Ghost_Entity (Priv_T) then
20239 -- The Ghost policy in effect at the point of declaration and at the
20240 -- point of completion must match (SPARK RM 6.9(14)).
20242 Check_Ghost_Completion (Priv_T, Full_T);
20244 -- Propagate the attributes related to pragma Ghost from the private
20245 -- to the full view.
20247 Mark_Full_View_As_Ghost (Priv_T, Full_T);
20250 -- Propagate invariant-related attributes from the private view to the
20251 -- full view and its base type.
20253 Propagate_Invariant_Attributes (Full_T, From_Typ => Priv_T);
20254 Propagate_Invariant_Attributes (Base_Type (Full_T), From_Typ => Priv_T);
20256 -- AI12-0041: Detect an attempt to inherit a class-wide type invariant
20257 -- in the full view without advertising the inheritance in the partial
20258 -- view. This can only occur when the partial view has no parent type
20259 -- and the full view has an interface as a parent. Any other scenarios
20260 -- are illegal because implemented interfaces must match between the
20263 if Is_Tagged_Type (Priv_T) and then Is_Tagged_Type (Full_T) then
20265 Full_Par : constant Entity_Id := Etype (Full_T);
20266 Priv_Par : constant Entity_Id := Etype (Priv_T);
20269 if not Is_Interface (Priv_Par)
20270 and then Is_Interface (Full_Par)
20271 and then Has_Inheritable_Invariants (Full_Par)
20274 ("hidden inheritance of class-wide type invariants not "
20280 -- Propagate predicates to full type, and predicate function if already
20281 -- defined. It is not clear that this can actually happen? the partial
20282 -- view cannot be frozen yet, and the predicate function has not been
20283 -- built. Still it is a cheap check and seems safer to make it.
20285 if Has_Predicates (Priv_T) then
20286 Set_Has_Predicates (Full_T);
20288 if Present (Predicate_Function (Priv_T)) then
20289 Set_Predicate_Function (Full_T, Predicate_Function (Priv_T));
20292 end Process_Full_View;
20294 -----------------------------------
20295 -- Process_Incomplete_Dependents --
20296 -----------------------------------
20298 procedure Process_Incomplete_Dependents
20300 Full_T : Entity_Id;
20303 Inc_Elmt : Elmt_Id;
20304 Priv_Dep : Entity_Id;
20305 New_Subt : Entity_Id;
20307 Disc_Constraint : Elist_Id;
20310 if No (Private_Dependents (Inc_T)) then
20314 -- Itypes that may be generated by the completion of an incomplete
20315 -- subtype are not used by the back-end and not attached to the tree.
20316 -- They are created only for constraint-checking purposes.
20318 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
20319 while Present (Inc_Elmt) loop
20320 Priv_Dep := Node (Inc_Elmt);
20322 if Ekind (Priv_Dep) = E_Subprogram_Type then
20324 -- An Access_To_Subprogram type may have a return type or a
20325 -- parameter type that is incomplete. Replace with the full view.
20327 if Etype (Priv_Dep) = Inc_T then
20328 Set_Etype (Priv_Dep, Full_T);
20332 Formal : Entity_Id;
20335 Formal := First_Formal (Priv_Dep);
20336 while Present (Formal) loop
20337 if Etype (Formal) = Inc_T then
20338 Set_Etype (Formal, Full_T);
20341 Next_Formal (Formal);
20345 elsif Is_Overloadable (Priv_Dep) then
20347 -- If a subprogram in the incomplete dependents list is primitive
20348 -- for a tagged full type then mark it as a dispatching operation,
20349 -- check whether it overrides an inherited subprogram, and check
20350 -- restrictions on its controlling formals. Note that a protected
20351 -- operation is never dispatching: only its wrapper operation
20352 -- (which has convention Ada) is.
20354 if Is_Tagged_Type (Full_T)
20355 and then Is_Primitive (Priv_Dep)
20356 and then Convention (Priv_Dep) /= Convention_Protected
20358 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
20359 Set_Is_Dispatching_Operation (Priv_Dep);
20360 Check_Controlling_Formals (Full_T, Priv_Dep);
20363 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
20365 -- Can happen during processing of a body before the completion
20366 -- of a TA type. Ignore, because spec is also on dependent list.
20370 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
20371 -- corresponding subtype of the full view.
20373 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype then
20374 Set_Subtype_Indication
20375 (Parent (Priv_Dep), New_Occurrence_Of (Full_T, Sloc (Priv_Dep)));
20376 Set_Etype (Priv_Dep, Full_T);
20377 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
20378 Set_Analyzed (Parent (Priv_Dep), False);
20380 -- Reanalyze the declaration, suppressing the call to
20381 -- Enter_Name to avoid duplicate names.
20383 Analyze_Subtype_Declaration
20384 (N => Parent (Priv_Dep),
20387 -- Dependent is a subtype
20390 -- We build a new subtype indication using the full view of the
20391 -- incomplete parent. The discriminant constraints have been
20392 -- elaborated already at the point of the subtype declaration.
20394 New_Subt := Create_Itype (E_Void, N);
20396 if Has_Discriminants (Full_T) then
20397 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
20399 Disc_Constraint := No_Elist;
20402 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
20403 Set_Full_View (Priv_Dep, New_Subt);
20406 Next_Elmt (Inc_Elmt);
20408 end Process_Incomplete_Dependents;
20410 --------------------------------
20411 -- Process_Range_Expr_In_Decl --
20412 --------------------------------
20414 procedure Process_Range_Expr_In_Decl
20417 Subtyp : Entity_Id := Empty;
20418 Check_List : List_Id := Empty_List;
20419 R_Check_Off : Boolean := False;
20420 In_Iter_Schm : Boolean := False)
20423 R_Checks : Check_Result;
20424 Insert_Node : Node_Id;
20425 Def_Id : Entity_Id;
20428 Analyze_And_Resolve (R, Base_Type (T));
20430 if Nkind (R) = N_Range then
20432 -- In SPARK, all ranges should be static, with the exception of the
20433 -- discrete type definition of a loop parameter specification.
20435 if not In_Iter_Schm
20436 and then not Is_OK_Static_Range (R)
20438 Check_SPARK_05_Restriction ("range should be static", R);
20441 Lo := Low_Bound (R);
20442 Hi := High_Bound (R);
20444 -- Validity checks on the range of a quantified expression are
20445 -- delayed until the construct is transformed into a loop.
20447 if Nkind (Parent (R)) = N_Loop_Parameter_Specification
20448 and then Nkind (Parent (Parent (R))) = N_Quantified_Expression
20452 -- We need to ensure validity of the bounds here, because if we
20453 -- go ahead and do the expansion, then the expanded code will get
20454 -- analyzed with range checks suppressed and we miss the check.
20456 -- WARNING: The capture of the range bounds with xxx_FIRST/_LAST and
20457 -- the temporaries generated by routine Remove_Side_Effects by means
20458 -- of validity checks must use the same names. When a range appears
20459 -- in the parent of a generic, the range is processed with checks
20460 -- disabled as part of the generic context and with checks enabled
20461 -- for code generation purposes. This leads to link issues as the
20462 -- generic contains references to xxx_FIRST/_LAST, but the inlined
20463 -- template sees the temporaries generated by Remove_Side_Effects.
20466 Validity_Check_Range (R, Subtyp);
20469 -- If there were errors in the declaration, try and patch up some
20470 -- common mistakes in the bounds. The cases handled are literals
20471 -- which are Integer where the expected type is Real and vice versa.
20472 -- These corrections allow the compilation process to proceed further
20473 -- along since some basic assumptions of the format of the bounds
20476 if Etype (R) = Any_Type then
20477 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
20479 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
20481 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
20483 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
20485 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
20487 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
20489 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
20491 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
20498 -- If the bounds of the range have been mistakenly given as string
20499 -- literals (perhaps in place of character literals), then an error
20500 -- has already been reported, but we rewrite the string literal as a
20501 -- bound of the range's type to avoid blowups in later processing
20502 -- that looks at static values.
20504 if Nkind (Lo) = N_String_Literal then
20506 Make_Attribute_Reference (Sloc (Lo),
20507 Prefix => New_Occurrence_Of (T, Sloc (Lo)),
20508 Attribute_Name => Name_First));
20509 Analyze_And_Resolve (Lo);
20512 if Nkind (Hi) = N_String_Literal then
20514 Make_Attribute_Reference (Sloc (Hi),
20515 Prefix => New_Occurrence_Of (T, Sloc (Hi)),
20516 Attribute_Name => Name_First));
20517 Analyze_And_Resolve (Hi);
20520 -- If bounds aren't scalar at this point then exit, avoiding
20521 -- problems with further processing of the range in this procedure.
20523 if not Is_Scalar_Type (Etype (Lo)) then
20527 -- Resolve (actually Sem_Eval) has checked that the bounds are in
20528 -- then range of the base type. Here we check whether the bounds
20529 -- are in the range of the subtype itself. Note that if the bounds
20530 -- represent the null range the Constraint_Error exception should
20533 -- ??? The following code should be cleaned up as follows
20535 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
20536 -- is done in the call to Range_Check (R, T); below
20538 -- 2. The use of R_Check_Off should be investigated and possibly
20539 -- removed, this would clean up things a bit.
20541 if Is_Null_Range (Lo, Hi) then
20545 -- Capture values of bounds and generate temporaries for them
20546 -- if needed, before applying checks, since checks may cause
20547 -- duplication of the expression without forcing evaluation.
20549 -- The forced evaluation removes side effects from expressions,
20550 -- which should occur also in GNATprove mode. Otherwise, we end up
20551 -- with unexpected insertions of actions at places where this is
20552 -- not supposed to occur, e.g. on default parameters of a call.
20554 if Expander_Active or GNATprove_Mode then
20556 -- Call Force_Evaluation to create declarations as needed to
20557 -- deal with side effects, and also create typ_FIRST/LAST
20558 -- entities for bounds if we have a subtype name.
20560 -- Note: we do this transformation even if expansion is not
20561 -- active if we are in GNATprove_Mode since the transformation
20562 -- is in general required to ensure that the resulting tree has
20563 -- proper Ada semantics.
20566 (Lo, Related_Id => Subtyp, Is_Low_Bound => True);
20568 (Hi, Related_Id => Subtyp, Is_High_Bound => True);
20571 -- We use a flag here instead of suppressing checks on the type
20572 -- because the type we check against isn't necessarily the place
20573 -- where we put the check.
20575 if not R_Check_Off then
20576 R_Checks := Get_Range_Checks (R, T);
20578 -- Look up tree to find an appropriate insertion point. We
20579 -- can't just use insert_actions because later processing
20580 -- depends on the insertion node. Prior to Ada 2012 the
20581 -- insertion point could only be a declaration or a loop, but
20582 -- quantified expressions can appear within any context in an
20583 -- expression, and the insertion point can be any statement,
20584 -- pragma, or declaration.
20586 Insert_Node := Parent (R);
20587 while Present (Insert_Node) loop
20589 Nkind (Insert_Node) in N_Declaration
20592 (Insert_Node, N_Component_Declaration,
20593 N_Loop_Parameter_Specification,
20594 N_Function_Specification,
20595 N_Procedure_Specification);
20597 exit when Nkind (Insert_Node) in N_Later_Decl_Item
20598 or else Nkind (Insert_Node) in
20599 N_Statement_Other_Than_Procedure_Call
20600 or else Nkind_In (Insert_Node, N_Procedure_Call_Statement,
20603 Insert_Node := Parent (Insert_Node);
20606 -- Why would Type_Decl not be present??? Without this test,
20607 -- short regression tests fail.
20609 if Present (Insert_Node) then
20611 -- Case of loop statement. Verify that the range is part
20612 -- of the subtype indication of the iteration scheme.
20614 if Nkind (Insert_Node) = N_Loop_Statement then
20619 Indic := Parent (R);
20620 while Present (Indic)
20621 and then Nkind (Indic) /= N_Subtype_Indication
20623 Indic := Parent (Indic);
20626 if Present (Indic) then
20627 Def_Id := Etype (Subtype_Mark (Indic));
20629 Insert_Range_Checks
20633 Sloc (Insert_Node),
20635 Do_Before => True);
20639 -- Insertion before a declaration. If the declaration
20640 -- includes discriminants, the list of applicable checks
20641 -- is given by the caller.
20643 elsif Nkind (Insert_Node) in N_Declaration then
20644 Def_Id := Defining_Identifier (Insert_Node);
20646 if (Ekind (Def_Id) = E_Record_Type
20647 and then Depends_On_Discriminant (R))
20649 (Ekind (Def_Id) = E_Protected_Type
20650 and then Has_Discriminants (Def_Id))
20652 Append_Range_Checks
20654 Check_List, Def_Id, Sloc (Insert_Node), R);
20657 Insert_Range_Checks
20659 Insert_Node, Def_Id, Sloc (Insert_Node), R);
20663 -- Insertion before a statement. Range appears in the
20664 -- context of a quantified expression. Insertion will
20665 -- take place when expression is expanded.
20674 -- Case of other than an explicit N_Range node
20676 -- The forced evaluation removes side effects from expressions, which
20677 -- should occur also in GNATprove mode. Otherwise, we end up with
20678 -- unexpected insertions of actions at places where this is not
20679 -- supposed to occur, e.g. on default parameters of a call.
20681 elsif Expander_Active or GNATprove_Mode then
20682 Get_Index_Bounds (R, Lo, Hi);
20683 Force_Evaluation (Lo);
20684 Force_Evaluation (Hi);
20686 end Process_Range_Expr_In_Decl;
20688 --------------------------------------
20689 -- Process_Real_Range_Specification --
20690 --------------------------------------
20692 procedure Process_Real_Range_Specification (Def : Node_Id) is
20693 Spec : constant Node_Id := Real_Range_Specification (Def);
20696 Err : Boolean := False;
20698 procedure Analyze_Bound (N : Node_Id);
20699 -- Analyze and check one bound
20701 -------------------
20702 -- Analyze_Bound --
20703 -------------------
20705 procedure Analyze_Bound (N : Node_Id) is
20707 Analyze_And_Resolve (N, Any_Real);
20709 if not Is_OK_Static_Expression (N) then
20710 Flag_Non_Static_Expr
20711 ("bound in real type definition is not static!", N);
20716 -- Start of processing for Process_Real_Range_Specification
20719 if Present (Spec) then
20720 Lo := Low_Bound (Spec);
20721 Hi := High_Bound (Spec);
20722 Analyze_Bound (Lo);
20723 Analyze_Bound (Hi);
20725 -- If error, clear away junk range specification
20728 Set_Real_Range_Specification (Def, Empty);
20731 end Process_Real_Range_Specification;
20733 ---------------------
20734 -- Process_Subtype --
20735 ---------------------
20737 function Process_Subtype
20739 Related_Nod : Node_Id;
20740 Related_Id : Entity_Id := Empty;
20741 Suffix : Character := ' ') return Entity_Id
20744 Def_Id : Entity_Id;
20745 Error_Node : Node_Id;
20746 Full_View_Id : Entity_Id;
20747 Subtype_Mark_Id : Entity_Id;
20749 May_Have_Null_Exclusion : Boolean;
20751 procedure Check_Incomplete (T : Node_Id);
20752 -- Called to verify that an incomplete type is not used prematurely
20754 ----------------------
20755 -- Check_Incomplete --
20756 ----------------------
20758 procedure Check_Incomplete (T : Node_Id) is
20760 -- Ada 2005 (AI-412): Incomplete subtypes are legal
20762 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
20764 not (Ada_Version >= Ada_2005
20766 (Nkind (Parent (T)) = N_Subtype_Declaration
20767 or else (Nkind (Parent (T)) = N_Subtype_Indication
20768 and then Nkind (Parent (Parent (T))) =
20769 N_Subtype_Declaration)))
20771 Error_Msg_N ("invalid use of type before its full declaration", T);
20773 end Check_Incomplete;
20775 -- Start of processing for Process_Subtype
20778 -- Case of no constraints present
20780 if Nkind (S) /= N_Subtype_Indication then
20782 Check_Incomplete (S);
20785 -- Ada 2005 (AI-231): Static check
20787 if Ada_Version >= Ada_2005
20788 and then Present (P)
20789 and then Null_Exclusion_Present (P)
20790 and then Nkind (P) /= N_Access_To_Object_Definition
20791 and then not Is_Access_Type (Entity (S))
20793 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
20796 -- The following is ugly, can't we have a range or even a flag???
20798 May_Have_Null_Exclusion :=
20799 Nkind_In (P, N_Access_Definition,
20800 N_Access_Function_Definition,
20801 N_Access_Procedure_Definition,
20802 N_Access_To_Object_Definition,
20804 N_Component_Definition)
20806 Nkind_In (P, N_Derived_Type_Definition,
20807 N_Discriminant_Specification,
20808 N_Formal_Object_Declaration,
20809 N_Object_Declaration,
20810 N_Object_Renaming_Declaration,
20811 N_Parameter_Specification,
20812 N_Subtype_Declaration);
20814 -- Create an Itype that is a duplicate of Entity (S) but with the
20815 -- null-exclusion attribute.
20817 if May_Have_Null_Exclusion
20818 and then Is_Access_Type (Entity (S))
20819 and then Null_Exclusion_Present (P)
20821 -- No need to check the case of an access to object definition.
20822 -- It is correct to define double not-null pointers.
20825 -- type Not_Null_Int_Ptr is not null access Integer;
20826 -- type Acc is not null access Not_Null_Int_Ptr;
20828 and then Nkind (P) /= N_Access_To_Object_Definition
20830 if Can_Never_Be_Null (Entity (S)) then
20831 case Nkind (Related_Nod) is
20832 when N_Full_Type_Declaration =>
20833 if Nkind (Type_Definition (Related_Nod))
20834 in N_Array_Type_Definition
20838 (Component_Definition
20839 (Type_Definition (Related_Nod)));
20842 Subtype_Indication (Type_Definition (Related_Nod));
20845 when N_Subtype_Declaration =>
20846 Error_Node := Subtype_Indication (Related_Nod);
20848 when N_Object_Declaration =>
20849 Error_Node := Object_Definition (Related_Nod);
20851 when N_Component_Declaration =>
20853 Subtype_Indication (Component_Definition (Related_Nod));
20855 when N_Allocator =>
20856 Error_Node := Expression (Related_Nod);
20859 pragma Assert (False);
20860 Error_Node := Related_Nod;
20864 ("`NOT NULL` not allowed (& already excludes null)",
20870 Create_Null_Excluding_Itype
20872 Related_Nod => P));
20873 Set_Entity (S, Etype (S));
20878 -- Case of constraint present, so that we have an N_Subtype_Indication
20879 -- node (this node is created only if constraints are present).
20882 Find_Type (Subtype_Mark (S));
20884 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
20886 (Nkind (Parent (S)) = N_Subtype_Declaration
20887 and then Is_Itype (Defining_Identifier (Parent (S))))
20889 Check_Incomplete (Subtype_Mark (S));
20893 Subtype_Mark_Id := Entity (Subtype_Mark (S));
20895 -- Explicit subtype declaration case
20897 if Nkind (P) = N_Subtype_Declaration then
20898 Def_Id := Defining_Identifier (P);
20900 -- Explicit derived type definition case
20902 elsif Nkind (P) = N_Derived_Type_Definition then
20903 Def_Id := Defining_Identifier (Parent (P));
20905 -- Implicit case, the Def_Id must be created as an implicit type.
20906 -- The one exception arises in the case of concurrent types, array
20907 -- and access types, where other subsidiary implicit types may be
20908 -- created and must appear before the main implicit type. In these
20909 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
20910 -- has not yet been called to create Def_Id.
20913 if Is_Array_Type (Subtype_Mark_Id)
20914 or else Is_Concurrent_Type (Subtype_Mark_Id)
20915 or else Is_Access_Type (Subtype_Mark_Id)
20919 -- For the other cases, we create a new unattached Itype,
20920 -- and set the indication to ensure it gets attached later.
20924 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
20928 -- If the kind of constraint is invalid for this kind of type,
20929 -- then give an error, and then pretend no constraint was given.
20931 if not Is_Valid_Constraint_Kind
20932 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
20935 ("incorrect constraint for this kind of type", Constraint (S));
20937 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
20939 -- Set Ekind of orphan itype, to prevent cascaded errors
20941 if Present (Def_Id) then
20942 Set_Ekind (Def_Id, Ekind (Any_Type));
20945 -- Make recursive call, having got rid of the bogus constraint
20947 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
20950 -- Remaining processing depends on type. Select on Base_Type kind to
20951 -- ensure getting to the concrete type kind in the case of a private
20952 -- subtype (needed when only doing semantic analysis).
20954 case Ekind (Base_Type (Subtype_Mark_Id)) is
20955 when Access_Kind =>
20957 -- If this is a constraint on a class-wide type, discard it.
20958 -- There is currently no way to express a partial discriminant
20959 -- constraint on a type with unknown discriminants. This is
20960 -- a pathology that the ACATS wisely decides not to test.
20962 if Is_Class_Wide_Type (Designated_Type (Subtype_Mark_Id)) then
20963 if Comes_From_Source (S) then
20965 ("constraint on class-wide type ignored??",
20969 if Nkind (P) = N_Subtype_Declaration then
20970 Set_Subtype_Indication (P,
20971 New_Occurrence_Of (Subtype_Mark_Id, Sloc (S)));
20974 return Subtype_Mark_Id;
20977 Constrain_Access (Def_Id, S, Related_Nod);
20980 and then Is_Itype (Designated_Type (Def_Id))
20981 and then Nkind (Related_Nod) = N_Subtype_Declaration
20982 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
20984 Build_Itype_Reference
20985 (Designated_Type (Def_Id), Related_Nod);
20989 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
20991 when Decimal_Fixed_Point_Kind =>
20992 Constrain_Decimal (Def_Id, S);
20994 when Enumeration_Kind =>
20995 Constrain_Enumeration (Def_Id, S);
20996 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
20998 when Ordinary_Fixed_Point_Kind =>
20999 Constrain_Ordinary_Fixed (Def_Id, S);
21002 Constrain_Float (Def_Id, S);
21004 when Integer_Kind =>
21005 Constrain_Integer (Def_Id, S);
21006 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
21008 when E_Record_Type |
21011 E_Incomplete_Type =>
21012 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
21014 if Ekind (Def_Id) = E_Incomplete_Type then
21015 Set_Private_Dependents (Def_Id, New_Elmt_List);
21018 when Private_Kind =>
21019 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
21021 -- The base type may be private but Def_Id may be a full view
21024 if Is_Private_Type (Def_Id) then
21025 Set_Private_Dependents (Def_Id, New_Elmt_List);
21028 -- In case of an invalid constraint prevent further processing
21029 -- since the type constructed is missing expected fields.
21031 if Etype (Def_Id) = Any_Type then
21035 -- If the full view is that of a task with discriminants,
21036 -- we must constrain both the concurrent type and its
21037 -- corresponding record type. Otherwise we will just propagate
21038 -- the constraint to the full view, if available.
21040 if Present (Full_View (Subtype_Mark_Id))
21041 and then Has_Discriminants (Subtype_Mark_Id)
21042 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
21045 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
21047 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
21048 Constrain_Concurrent (Full_View_Id, S,
21049 Related_Nod, Related_Id, Suffix);
21050 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
21051 Set_Full_View (Def_Id, Full_View_Id);
21053 -- Introduce an explicit reference to the private subtype,
21054 -- to prevent scope anomalies in gigi if first use appears
21055 -- in a nested context, e.g. a later function body.
21056 -- Should this be generated in other contexts than a full
21057 -- type declaration?
21059 if Is_Itype (Def_Id)
21061 Nkind (Parent (P)) = N_Full_Type_Declaration
21063 Build_Itype_Reference (Def_Id, Parent (P));
21067 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
21070 when Concurrent_Kind =>
21071 Constrain_Concurrent (Def_Id, S,
21072 Related_Nod, Related_Id, Suffix);
21075 Error_Msg_N ("invalid subtype mark in subtype indication", S);
21078 -- Size and Convention are always inherited from the base type
21080 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
21081 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
21085 end Process_Subtype;
21087 --------------------------------------------
21088 -- Propagate_Default_Init_Cond_Attributes --
21089 --------------------------------------------
21091 procedure Propagate_Default_Init_Cond_Attributes
21092 (From_Typ : Entity_Id;
21093 To_Typ : Entity_Id;
21094 Parent_To_Derivation : Boolean := False;
21095 Private_To_Full_View : Boolean := False)
21097 procedure Remove_Default_Init_Cond_Procedure (Typ : Entity_Id);
21098 -- Remove the default initial condition procedure (if any) from the
21099 -- Subprograms_For_Type chain of type Typ.
21101 ----------------------------------------
21102 -- Remove_Default_Init_Cond_Procedure --
21103 ----------------------------------------
21105 procedure Remove_Default_Init_Cond_Procedure (Typ : Entity_Id) is
21106 Subps : constant Elist_Id := Subprograms_For_Type (Typ);
21107 Subp_Elmt : Elmt_Id;
21108 Subp_Id : Entity_Id;
21111 if Present (Subps) then
21112 Subp_Elmt := First_Elmt (Subps);
21113 while Present (Subp_Elmt) loop
21114 Subp_Id := Node (Subp_Elmt);
21116 if Is_Default_Init_Cond_Procedure (Subp_Id) then
21117 Remove_Elmt (Subps, Subp_Elmt);
21121 Next_Elmt (Subp_Elmt);
21124 end Remove_Default_Init_Cond_Procedure;
21128 Inherit_Procedure : Boolean := False;
21130 -- Start of processing for Propagate_Default_Init_Cond_Attributes
21133 if Has_Default_Init_Cond (From_Typ) then
21135 -- A derived type inherits the attributes from its parent type
21137 if Parent_To_Derivation then
21138 Set_Has_Inherited_Default_Init_Cond (To_Typ);
21140 -- A full view shares the attributes with its private view
21143 Set_Has_Default_Init_Cond (To_Typ);
21146 Inherit_Procedure := True;
21148 -- Due to the order of expansion, a derived private type is processed
21149 -- by two routines which both attempt to set the attributes related
21150 -- to pragma Default_Initial_Condition - Build_Derived_Type and then
21151 -- Process_Full_View.
21154 -- type Parent_Typ is private
21155 -- with Default_Initial_Condition ...;
21157 -- type Parent_Typ is ...;
21160 -- with Pack; use Pack;
21161 -- package Pack_2 is
21162 -- type Deriv_Typ is private
21163 -- with Default_Initial_Condition ...;
21165 -- type Deriv_Typ is new Parent_Typ;
21168 -- When Build_Derived_Type operates, it sets the attributes on the
21169 -- full view without taking into account that the private view may
21170 -- define its own default initial condition procedure. This becomes
21171 -- apparent in Process_Full_View which must undo some of the work by
21172 -- Build_Derived_Type and propagate the attributes from the private
21173 -- to the full view.
21175 if Private_To_Full_View then
21176 Set_Has_Inherited_Default_Init_Cond (To_Typ, False);
21177 Remove_Default_Init_Cond_Procedure (To_Typ);
21180 -- A type must inherit the default initial condition procedure from a
21181 -- parent type when the parent itself is inheriting the procedure or
21182 -- when it is defining one. This circuitry is also used when dealing
21183 -- with the private / full view of a type.
21185 elsif Has_Inherited_Default_Init_Cond (From_Typ)
21186 or (Parent_To_Derivation
21187 and Present (Get_Pragma
21188 (From_Typ, Pragma_Default_Initial_Condition)))
21190 Set_Has_Inherited_Default_Init_Cond (To_Typ);
21191 Inherit_Procedure := True;
21194 if Inherit_Procedure
21195 and then No (Default_Init_Cond_Procedure (To_Typ))
21197 Set_Default_Init_Cond_Procedure
21198 (To_Typ, Default_Init_Cond_Procedure (From_Typ));
21200 end Propagate_Default_Init_Cond_Attributes;
21202 -----------------------------
21203 -- Record_Type_Declaration --
21204 -----------------------------
21206 procedure Record_Type_Declaration
21211 Def : constant Node_Id := Type_Definition (N);
21212 Is_Tagged : Boolean;
21213 Tag_Comp : Entity_Id;
21216 -- These flags must be initialized before calling Process_Discriminants
21217 -- because this routine makes use of them.
21219 Set_Ekind (T, E_Record_Type);
21221 Init_Size_Align (T);
21222 Set_Interfaces (T, No_Elist);
21223 Set_Stored_Constraint (T, No_Elist);
21224 Set_Default_SSO (T);
21228 if Ada_Version < Ada_2005 or else not Interface_Present (Def) then
21229 if Limited_Present (Def) then
21230 Check_SPARK_05_Restriction ("limited is not allowed", N);
21233 if Abstract_Present (Def) then
21234 Check_SPARK_05_Restriction ("abstract is not allowed", N);
21237 -- The flag Is_Tagged_Type might have already been set by
21238 -- Find_Type_Name if it detected an error for declaration T. This
21239 -- arises in the case of private tagged types where the full view
21240 -- omits the word tagged.
21243 Tagged_Present (Def)
21244 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
21246 Set_Is_Limited_Record (T, Limited_Present (Def));
21249 Set_Is_Tagged_Type (T, True);
21250 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
21253 -- Type is abstract if full declaration carries keyword, or if
21254 -- previous partial view did.
21256 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
21257 or else Abstract_Present (Def));
21260 Check_SPARK_05_Restriction ("interface is not allowed", N);
21263 Analyze_Interface_Declaration (T, Def);
21265 if Present (Discriminant_Specifications (N)) then
21267 ("interface types cannot have discriminants",
21268 Defining_Identifier
21269 (First (Discriminant_Specifications (N))));
21273 -- First pass: if there are self-referential access components,
21274 -- create the required anonymous access type declarations, and if
21275 -- need be an incomplete type declaration for T itself.
21277 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
21279 if Ada_Version >= Ada_2005
21280 and then Present (Interface_List (Def))
21282 Check_Interfaces (N, Def);
21285 Ifaces_List : Elist_Id;
21288 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
21289 -- already in the parents.
21293 Ifaces_List => Ifaces_List,
21294 Exclude_Parents => True);
21296 Set_Interfaces (T, Ifaces_List);
21300 -- Records constitute a scope for the component declarations within.
21301 -- The scope is created prior to the processing of these declarations.
21302 -- Discriminants are processed first, so that they are visible when
21303 -- processing the other components. The Ekind of the record type itself
21304 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
21306 -- Enter record scope
21310 -- If an incomplete or private type declaration was already given for
21311 -- the type, then this scope already exists, and the discriminants have
21312 -- been declared within. We must verify that the full declaration
21313 -- matches the incomplete one.
21315 Check_Or_Process_Discriminants (N, T, Prev);
21317 Set_Is_Constrained (T, not Has_Discriminants (T));
21318 Set_Has_Delayed_Freeze (T, True);
21320 -- For tagged types add a manually analyzed component corresponding
21321 -- to the component _tag, the corresponding piece of tree will be
21322 -- expanded as part of the freezing actions if it is not a CPP_Class.
21326 -- Do not add the tag unless we are in expansion mode
21328 if Expander_Active then
21329 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
21330 Enter_Name (Tag_Comp);
21332 Set_Ekind (Tag_Comp, E_Component);
21333 Set_Is_Tag (Tag_Comp);
21334 Set_Is_Aliased (Tag_Comp);
21335 Set_Etype (Tag_Comp, RTE (RE_Tag));
21336 Set_DT_Entry_Count (Tag_Comp, No_Uint);
21337 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
21338 Init_Component_Location (Tag_Comp);
21340 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
21341 -- implemented interfaces.
21343 if Has_Interfaces (T) then
21344 Add_Interface_Tag_Components (N, T);
21348 Make_Class_Wide_Type (T);
21349 Set_Direct_Primitive_Operations (T, New_Elmt_List);
21352 -- We must suppress range checks when processing record components in
21353 -- the presence of discriminants, since we don't want spurious checks to
21354 -- be generated during their analysis, but Suppress_Range_Checks flags
21355 -- must be reset the after processing the record definition.
21357 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
21358 -- couldn't we just use the normal range check suppression method here.
21359 -- That would seem cleaner ???
21361 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
21362 Set_Kill_Range_Checks (T, True);
21363 Record_Type_Definition (Def, Prev);
21364 Set_Kill_Range_Checks (T, False);
21366 Record_Type_Definition (Def, Prev);
21369 -- Exit from record scope
21373 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
21374 -- the implemented interfaces and associate them an aliased entity.
21377 and then not Is_Empty_List (Interface_List (Def))
21379 Derive_Progenitor_Subprograms (T, T);
21382 Check_Function_Writable_Actuals (N);
21383 end Record_Type_Declaration;
21385 ----------------------------
21386 -- Record_Type_Definition --
21387 ----------------------------
21389 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
21390 Component : Entity_Id;
21391 Ctrl_Components : Boolean := False;
21392 Final_Storage_Only : Boolean;
21396 if Ekind (Prev_T) = E_Incomplete_Type then
21397 T := Full_View (Prev_T);
21402 -- In SPARK, tagged types and type extensions may only be declared in
21403 -- the specification of library unit packages.
21405 if Present (Def) and then Is_Tagged_Type (T) then
21411 if Nkind (Parent (Def)) = N_Full_Type_Declaration then
21412 Typ := Parent (Def);
21415 (Nkind (Parent (Def)) = N_Derived_Type_Definition);
21416 Typ := Parent (Parent (Def));
21419 Ctxt := Parent (Typ);
21421 if Nkind (Ctxt) = N_Package_Body
21422 and then Nkind (Parent (Ctxt)) = N_Compilation_Unit
21424 Check_SPARK_05_Restriction
21425 ("type should be defined in package specification", Typ);
21427 elsif Nkind (Ctxt) /= N_Package_Specification
21428 or else Nkind (Parent (Parent (Ctxt))) /= N_Compilation_Unit
21430 Check_SPARK_05_Restriction
21431 ("type should be defined in library unit package", Typ);
21436 Final_Storage_Only := not Is_Controlled_Active (T);
21438 -- Ada 2005: Check whether an explicit Limited is present in a derived
21439 -- type declaration.
21441 if Nkind (Parent (Def)) = N_Derived_Type_Definition
21442 and then Limited_Present (Parent (Def))
21444 Set_Is_Limited_Record (T);
21447 -- If the component list of a record type is defined by the reserved
21448 -- word null and there is no discriminant part, then the record type has
21449 -- no components and all records of the type are null records (RM 3.7)
21450 -- This procedure is also called to process the extension part of a
21451 -- record extension, in which case the current scope may have inherited
21455 or else No (Component_List (Def))
21456 or else Null_Present (Component_List (Def))
21458 if not Is_Tagged_Type (T) then
21459 Check_SPARK_05_Restriction ("untagged record cannot be null", Def);
21463 Analyze_Declarations (Component_Items (Component_List (Def)));
21465 if Present (Variant_Part (Component_List (Def))) then
21466 Check_SPARK_05_Restriction ("variant part is not allowed", Def);
21467 Analyze (Variant_Part (Component_List (Def)));
21471 -- After completing the semantic analysis of the record definition,
21472 -- record components, both new and inherited, are accessible. Set their
21473 -- kind accordingly. Exclude malformed itypes from illegal declarations,
21474 -- whose Ekind may be void.
21476 Component := First_Entity (Current_Scope);
21477 while Present (Component) loop
21478 if Ekind (Component) = E_Void
21479 and then not Is_Itype (Component)
21481 Set_Ekind (Component, E_Component);
21482 Init_Component_Location (Component);
21485 Propagate_Concurrent_Flags (T, Etype (Component));
21487 if Ekind (Component) /= E_Component then
21490 -- Do not set Has_Controlled_Component on a class-wide equivalent
21491 -- type. See Make_CW_Equivalent_Type.
21493 elsif not Is_Class_Wide_Equivalent_Type (T)
21494 and then (Has_Controlled_Component (Etype (Component))
21495 or else (Chars (Component) /= Name_uParent
21496 and then Is_Controlled_Active
21497 (Etype (Component))))
21499 Set_Has_Controlled_Component (T, True);
21500 Final_Storage_Only :=
21502 and then Finalize_Storage_Only (Etype (Component));
21503 Ctrl_Components := True;
21506 Next_Entity (Component);
21509 -- A Type is Finalize_Storage_Only only if all its controlled components
21512 if Ctrl_Components then
21513 Set_Finalize_Storage_Only (T, Final_Storage_Only);
21516 -- Place reference to end record on the proper entity, which may
21517 -- be a partial view.
21519 if Present (Def) then
21520 Process_End_Label (Def, 'e', Prev_T);
21522 end Record_Type_Definition;
21524 ------------------------
21525 -- Replace_Components --
21526 ------------------------
21528 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
21529 function Process (N : Node_Id) return Traverse_Result;
21535 function Process (N : Node_Id) return Traverse_Result is
21539 if Nkind (N) = N_Discriminant_Specification then
21540 Comp := First_Discriminant (Typ);
21541 while Present (Comp) loop
21542 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21543 Set_Defining_Identifier (N, Comp);
21547 Next_Discriminant (Comp);
21550 elsif Nkind (N) = N_Component_Declaration then
21551 Comp := First_Component (Typ);
21552 while Present (Comp) loop
21553 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21554 Set_Defining_Identifier (N, Comp);
21558 Next_Component (Comp);
21565 procedure Replace is new Traverse_Proc (Process);
21567 -- Start of processing for Replace_Components
21571 end Replace_Components;
21573 -------------------------------
21574 -- Set_Completion_Referenced --
21575 -------------------------------
21577 procedure Set_Completion_Referenced (E : Entity_Id) is
21579 -- If in main unit, mark entity that is a completion as referenced,
21580 -- warnings go on the partial view when needed.
21582 if In_Extended_Main_Source_Unit (E) then
21583 Set_Referenced (E);
21585 end Set_Completion_Referenced;
21587 ---------------------
21588 -- Set_Default_SSO --
21589 ---------------------
21591 procedure Set_Default_SSO (T : Entity_Id) is
21593 case Opt.Default_SSO is
21597 Set_SSO_Set_Low_By_Default (T, True);
21599 Set_SSO_Set_High_By_Default (T, True);
21601 raise Program_Error;
21603 end Set_Default_SSO;
21605 ---------------------
21606 -- Set_Fixed_Range --
21607 ---------------------
21609 -- The range for fixed-point types is complicated by the fact that we
21610 -- do not know the exact end points at the time of the declaration. This
21611 -- is true for three reasons:
21613 -- A size clause may affect the fudging of the end-points.
21614 -- A small clause may affect the values of the end-points.
21615 -- We try to include the end-points if it does not affect the size.
21617 -- This means that the actual end-points must be established at the
21618 -- point when the type is frozen. Meanwhile, we first narrow the range
21619 -- as permitted (so that it will fit if necessary in a small specified
21620 -- size), and then build a range subtree with these narrowed bounds.
21621 -- Set_Fixed_Range constructs the range from real literal values, and
21622 -- sets the range as the Scalar_Range of the given fixed-point type entity.
21624 -- The parent of this range is set to point to the entity so that it is
21625 -- properly hooked into the tree (unlike normal Scalar_Range entries for
21626 -- other scalar types, which are just pointers to the range in the
21627 -- original tree, this would otherwise be an orphan).
21629 -- The tree is left unanalyzed. When the type is frozen, the processing
21630 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
21631 -- analyzed, and uses this as an indication that it should complete
21632 -- work on the range (it will know the final small and size values).
21634 procedure Set_Fixed_Range
21640 S : constant Node_Id :=
21642 Low_Bound => Make_Real_Literal (Loc, Lo),
21643 High_Bound => Make_Real_Literal (Loc, Hi));
21645 Set_Scalar_Range (E, S);
21648 -- Before the freeze point, the bounds of a fixed point are universal
21649 -- and carry the corresponding type.
21651 Set_Etype (Low_Bound (S), Universal_Real);
21652 Set_Etype (High_Bound (S), Universal_Real);
21653 end Set_Fixed_Range;
21655 ----------------------------------
21656 -- Set_Scalar_Range_For_Subtype --
21657 ----------------------------------
21659 procedure Set_Scalar_Range_For_Subtype
21660 (Def_Id : Entity_Id;
21664 Kind : constant Entity_Kind := Ekind (Def_Id);
21667 -- Defend against previous error
21669 if Nkind (R) = N_Error then
21673 Set_Scalar_Range (Def_Id, R);
21675 -- We need to link the range into the tree before resolving it so
21676 -- that types that are referenced, including importantly the subtype
21677 -- itself, are properly frozen (Freeze_Expression requires that the
21678 -- expression be properly linked into the tree). Of course if it is
21679 -- already linked in, then we do not disturb the current link.
21681 if No (Parent (R)) then
21682 Set_Parent (R, Def_Id);
21685 -- Reset the kind of the subtype during analysis of the range, to
21686 -- catch possible premature use in the bounds themselves.
21688 Set_Ekind (Def_Id, E_Void);
21689 Process_Range_Expr_In_Decl (R, Subt, Subtyp => Def_Id);
21690 Set_Ekind (Def_Id, Kind);
21691 end Set_Scalar_Range_For_Subtype;
21693 --------------------------------------------------------
21694 -- Set_Stored_Constraint_From_Discriminant_Constraint --
21695 --------------------------------------------------------
21697 procedure Set_Stored_Constraint_From_Discriminant_Constraint
21701 -- Make sure set if encountered during Expand_To_Stored_Constraint
21703 Set_Stored_Constraint (E, No_Elist);
21705 -- Give it the right value
21707 if Is_Constrained (E) and then Has_Discriminants (E) then
21708 Set_Stored_Constraint (E,
21709 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
21711 end Set_Stored_Constraint_From_Discriminant_Constraint;
21713 -------------------------------------
21714 -- Signed_Integer_Type_Declaration --
21715 -------------------------------------
21717 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
21718 Implicit_Base : Entity_Id;
21719 Base_Typ : Entity_Id;
21722 Errs : Boolean := False;
21726 function Can_Derive_From (E : Entity_Id) return Boolean;
21727 -- Determine whether given bounds allow derivation from specified type
21729 procedure Check_Bound (Expr : Node_Id);
21730 -- Check bound to make sure it is integral and static. If not, post
21731 -- appropriate error message and set Errs flag
21733 ---------------------
21734 -- Can_Derive_From --
21735 ---------------------
21737 -- Note we check both bounds against both end values, to deal with
21738 -- strange types like ones with a range of 0 .. -12341234.
21740 function Can_Derive_From (E : Entity_Id) return Boolean is
21741 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
21742 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
21744 return Lo <= Lo_Val and then Lo_Val <= Hi
21746 Lo <= Hi_Val and then Hi_Val <= Hi;
21747 end Can_Derive_From;
21753 procedure Check_Bound (Expr : Node_Id) is
21755 -- If a range constraint is used as an integer type definition, each
21756 -- bound of the range must be defined by a static expression of some
21757 -- integer type, but the two bounds need not have the same integer
21758 -- type (Negative bounds are allowed.) (RM 3.5.4)
21760 if not Is_Integer_Type (Etype (Expr)) then
21762 ("integer type definition bounds must be of integer type", Expr);
21765 elsif not Is_OK_Static_Expression (Expr) then
21766 Flag_Non_Static_Expr
21767 ("non-static expression used for integer type bound!", Expr);
21770 -- The bounds are folded into literals, and we set their type to be
21771 -- universal, to avoid typing difficulties: we cannot set the type
21772 -- of the literal to the new type, because this would be a forward
21773 -- reference for the back end, and if the original type is user-
21774 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
21777 if Is_Entity_Name (Expr) then
21778 Fold_Uint (Expr, Expr_Value (Expr), True);
21781 Set_Etype (Expr, Universal_Integer);
21785 -- Start of processing for Signed_Integer_Type_Declaration
21788 -- Create an anonymous base type
21791 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
21793 -- Analyze and check the bounds, they can be of any integer type
21795 Lo := Low_Bound (Def);
21796 Hi := High_Bound (Def);
21798 -- Arbitrarily use Integer as the type if either bound had an error
21800 if Hi = Error or else Lo = Error then
21801 Base_Typ := Any_Integer;
21802 Set_Error_Posted (T, True);
21804 -- Here both bounds are OK expressions
21807 Analyze_And_Resolve (Lo, Any_Integer);
21808 Analyze_And_Resolve (Hi, Any_Integer);
21814 Hi := Type_High_Bound (Standard_Long_Long_Integer);
21815 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
21818 -- Find type to derive from
21820 Lo_Val := Expr_Value (Lo);
21821 Hi_Val := Expr_Value (Hi);
21823 if Can_Derive_From (Standard_Short_Short_Integer) then
21824 Base_Typ := Base_Type (Standard_Short_Short_Integer);
21826 elsif Can_Derive_From (Standard_Short_Integer) then
21827 Base_Typ := Base_Type (Standard_Short_Integer);
21829 elsif Can_Derive_From (Standard_Integer) then
21830 Base_Typ := Base_Type (Standard_Integer);
21832 elsif Can_Derive_From (Standard_Long_Integer) then
21833 Base_Typ := Base_Type (Standard_Long_Integer);
21835 elsif Can_Derive_From (Standard_Long_Long_Integer) then
21836 Check_Restriction (No_Long_Long_Integers, Def);
21837 Base_Typ := Base_Type (Standard_Long_Long_Integer);
21840 Base_Typ := Base_Type (Standard_Long_Long_Integer);
21841 Error_Msg_N ("integer type definition bounds out of range", Def);
21842 Hi := Type_High_Bound (Standard_Long_Long_Integer);
21843 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
21847 -- Complete both implicit base and declared first subtype entities. The
21848 -- inheritance of the rep item chain ensures that SPARK-related pragmas
21849 -- are not clobbered when the signed integer type acts as a full view of
21852 Set_Etype (Implicit_Base, Base_Typ);
21853 Set_Size_Info (Implicit_Base, Base_Typ);
21854 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
21855 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
21856 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
21858 Set_Ekind (T, E_Signed_Integer_Subtype);
21859 Set_Etype (T, Implicit_Base);
21860 Set_Size_Info (T, Implicit_Base);
21861 Inherit_Rep_Item_Chain (T, Implicit_Base);
21862 Set_Scalar_Range (T, Def);
21863 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
21864 Set_Is_Constrained (T);
21865 end Signed_Integer_Type_Declaration;