1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2015, 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 classwide 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_Controlled_Component (T, False);
1441 Set_Has_Protected (T, False);
1443 -- Initialize field Finalization_Master explicitly to Empty, to avoid
1444 -- problems where an incomplete view of this entity has been previously
1445 -- established by a limited with and an overlaid version of this field
1446 -- (Stored_Constraint) was initialized for the incomplete view.
1448 -- This reset is performed in most cases except where the access type
1449 -- has been created for the purposes of allocating or deallocating a
1450 -- build-in-place object. Such access types have explicitly set pools
1451 -- and finalization masters.
1453 if No (Associated_Storage_Pool (T)) then
1454 Set_Finalization_Master (T, Empty);
1457 -- Ada 2005 (AI-231): Propagate the null-excluding and access-constant
1460 Set_Can_Never_Be_Null (T, Null_Exclusion_Present (Def));
1461 Set_Is_Access_Constant (T, Constant_Present (Def));
1462 end Access_Type_Declaration;
1464 ----------------------------------
1465 -- Add_Interface_Tag_Components --
1466 ----------------------------------
1468 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id) is
1469 Loc : constant Source_Ptr := Sloc (N);
1473 procedure Add_Tag (Iface : Entity_Id);
1474 -- Add tag for one of the progenitor interfaces
1480 procedure Add_Tag (Iface : Entity_Id) is
1487 pragma Assert (Is_Tagged_Type (Iface) and then Is_Interface (Iface));
1489 -- This is a reasonable place to propagate predicates
1491 if Has_Predicates (Iface) then
1492 Set_Has_Predicates (Typ);
1496 Make_Component_Definition (Loc,
1497 Aliased_Present => True,
1498 Subtype_Indication =>
1499 New_Occurrence_Of (RTE (RE_Interface_Tag), Loc));
1501 Tag := Make_Temporary (Loc, 'V');
1504 Make_Component_Declaration (Loc,
1505 Defining_Identifier => Tag,
1506 Component_Definition => Def);
1508 Analyze_Component_Declaration (Decl);
1510 Set_Analyzed (Decl);
1511 Set_Ekind (Tag, E_Component);
1513 Set_Is_Aliased (Tag);
1514 Set_Related_Type (Tag, Iface);
1515 Init_Component_Location (Tag);
1517 pragma Assert (Is_Frozen (Iface));
1519 Set_DT_Entry_Count (Tag,
1520 DT_Entry_Count (First_Entity (Iface)));
1522 if No (Last_Tag) then
1525 Insert_After (Last_Tag, Decl);
1530 -- If the ancestor has discriminants we need to give special support
1531 -- to store the offset_to_top value of the secondary dispatch tables.
1532 -- For this purpose we add a supplementary component just after the
1533 -- field that contains the tag associated with each secondary DT.
1535 if Typ /= Etype (Typ) and then Has_Discriminants (Etype (Typ)) then
1537 Make_Component_Definition (Loc,
1538 Subtype_Indication =>
1539 New_Occurrence_Of (RTE (RE_Storage_Offset), Loc));
1541 Offset := Make_Temporary (Loc, 'V');
1544 Make_Component_Declaration (Loc,
1545 Defining_Identifier => Offset,
1546 Component_Definition => Def);
1548 Analyze_Component_Declaration (Decl);
1550 Set_Analyzed (Decl);
1551 Set_Ekind (Offset, E_Component);
1552 Set_Is_Aliased (Offset);
1553 Set_Related_Type (Offset, Iface);
1554 Init_Component_Location (Offset);
1555 Insert_After (Last_Tag, Decl);
1566 -- Start of processing for Add_Interface_Tag_Components
1569 if not RTE_Available (RE_Interface_Tag) then
1571 ("(Ada 2005) interface types not supported by this run-time!",
1576 if Ekind (Typ) /= E_Record_Type
1577 or else (Is_Concurrent_Record_Type (Typ)
1578 and then Is_Empty_List (Abstract_Interface_List (Typ)))
1579 or else (not Is_Concurrent_Record_Type (Typ)
1580 and then No (Interfaces (Typ))
1581 and then Is_Empty_Elmt_List (Interfaces (Typ)))
1586 -- Find the current last tag
1588 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1589 Ext := Record_Extension_Part (Type_Definition (N));
1591 pragma Assert (Nkind (Type_Definition (N)) = N_Record_Definition);
1592 Ext := Type_Definition (N);
1597 if not (Present (Component_List (Ext))) then
1598 Set_Null_Present (Ext, False);
1600 Set_Component_List (Ext,
1601 Make_Component_List (Loc,
1602 Component_Items => L,
1603 Null_Present => False));
1605 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1606 L := Component_Items
1608 (Record_Extension_Part
1609 (Type_Definition (N))));
1611 L := Component_Items
1613 (Type_Definition (N)));
1616 -- Find the last tag component
1619 while Present (Comp) loop
1620 if Nkind (Comp) = N_Component_Declaration
1621 and then Is_Tag (Defining_Identifier (Comp))
1630 -- At this point L references the list of components and Last_Tag
1631 -- references the current last tag (if any). Now we add the tag
1632 -- corresponding with all the interfaces that are not implemented
1635 if Present (Interfaces (Typ)) then
1636 Elmt := First_Elmt (Interfaces (Typ));
1637 while Present (Elmt) loop
1638 Add_Tag (Node (Elmt));
1642 end Add_Interface_Tag_Components;
1644 -------------------------------------
1645 -- Add_Internal_Interface_Entities --
1646 -------------------------------------
1648 procedure Add_Internal_Interface_Entities (Tagged_Type : Entity_Id) is
1651 Iface_Elmt : Elmt_Id;
1652 Iface_Prim : Entity_Id;
1653 Ifaces_List : Elist_Id;
1654 New_Subp : Entity_Id := Empty;
1656 Restore_Scope : Boolean := False;
1659 pragma Assert (Ada_Version >= Ada_2005
1660 and then Is_Record_Type (Tagged_Type)
1661 and then Is_Tagged_Type (Tagged_Type)
1662 and then Has_Interfaces (Tagged_Type)
1663 and then not Is_Interface (Tagged_Type));
1665 -- Ensure that the internal entities are added to the scope of the type
1667 if Scope (Tagged_Type) /= Current_Scope then
1668 Push_Scope (Scope (Tagged_Type));
1669 Restore_Scope := True;
1672 Collect_Interfaces (Tagged_Type, Ifaces_List);
1674 Iface_Elmt := First_Elmt (Ifaces_List);
1675 while Present (Iface_Elmt) loop
1676 Iface := Node (Iface_Elmt);
1678 -- Originally we excluded here from this processing interfaces that
1679 -- are parents of Tagged_Type because their primitives are located
1680 -- in the primary dispatch table (and hence no auxiliary internal
1681 -- entities are required to handle secondary dispatch tables in such
1682 -- case). However, these auxiliary entities are also required to
1683 -- handle derivations of interfaces in formals of generics (see
1684 -- Derive_Subprograms).
1686 Elmt := First_Elmt (Primitive_Operations (Iface));
1687 while Present (Elmt) loop
1688 Iface_Prim := Node (Elmt);
1690 if not Is_Predefined_Dispatching_Operation (Iface_Prim) then
1692 Find_Primitive_Covering_Interface
1693 (Tagged_Type => Tagged_Type,
1694 Iface_Prim => Iface_Prim);
1696 if No (Prim) and then Serious_Errors_Detected > 0 then
1700 pragma Assert (Present (Prim));
1702 -- Ada 2012 (AI05-0197): If the name of the covering primitive
1703 -- differs from the name of the interface primitive then it is
1704 -- a private primitive inherited from a parent type. In such
1705 -- case, given that Tagged_Type covers the interface, the
1706 -- inherited private primitive becomes visible. For such
1707 -- purpose we add a new entity that renames the inherited
1708 -- private primitive.
1710 if Chars (Prim) /= Chars (Iface_Prim) then
1711 pragma Assert (Has_Suffix (Prim, 'P'));
1713 (New_Subp => New_Subp,
1714 Parent_Subp => Iface_Prim,
1715 Derived_Type => Tagged_Type,
1716 Parent_Type => Iface);
1717 Set_Alias (New_Subp, Prim);
1718 Set_Is_Abstract_Subprogram
1719 (New_Subp, Is_Abstract_Subprogram (Prim));
1723 (New_Subp => New_Subp,
1724 Parent_Subp => Iface_Prim,
1725 Derived_Type => Tagged_Type,
1726 Parent_Type => Iface);
1728 -- Ada 2005 (AI-251): Decorate internal entity Iface_Subp
1729 -- associated with interface types. These entities are
1730 -- only registered in the list of primitives of its
1731 -- corresponding tagged type because they are only used
1732 -- to fill the contents of the secondary dispatch tables.
1733 -- Therefore they are removed from the homonym chains.
1735 Set_Is_Hidden (New_Subp);
1736 Set_Is_Internal (New_Subp);
1737 Set_Alias (New_Subp, Prim);
1738 Set_Is_Abstract_Subprogram
1739 (New_Subp, Is_Abstract_Subprogram (Prim));
1740 Set_Interface_Alias (New_Subp, Iface_Prim);
1742 -- If the returned type is an interface then propagate it to
1743 -- the returned type. Needed by the thunk to generate the code
1744 -- which displaces "this" to reference the corresponding
1745 -- secondary dispatch table in the returned object.
1747 if Is_Interface (Etype (Iface_Prim)) then
1748 Set_Etype (New_Subp, Etype (Iface_Prim));
1751 -- Internal entities associated with interface types are only
1752 -- registered in the list of primitives of the tagged type.
1753 -- They are only used to fill the contents of the secondary
1754 -- dispatch tables. Therefore they are not needed in the
1757 Remove_Homonym (New_Subp);
1759 -- Hidden entities associated with interfaces must have set
1760 -- the Has_Delay_Freeze attribute to ensure that, in case
1761 -- of locally defined tagged types (or compiling with static
1762 -- dispatch tables generation disabled) the corresponding
1763 -- entry of the secondary dispatch table is filled when such
1764 -- an entity is frozen. This is an expansion activity that must
1765 -- be suppressed for ASIS because it leads to gigi elaboration
1766 -- issues in annotate mode.
1768 if not ASIS_Mode then
1769 Set_Has_Delayed_Freeze (New_Subp);
1777 Next_Elmt (Iface_Elmt);
1780 if Restore_Scope then
1783 end Add_Internal_Interface_Entities;
1785 -----------------------------------
1786 -- Analyze_Component_Declaration --
1787 -----------------------------------
1789 procedure Analyze_Component_Declaration (N : Node_Id) is
1790 Loc : constant Source_Ptr := Sloc (Component_Definition (N));
1791 Id : constant Entity_Id := Defining_Identifier (N);
1792 E : constant Node_Id := Expression (N);
1793 Typ : constant Node_Id :=
1794 Subtype_Indication (Component_Definition (N));
1798 function Contains_POC (Constr : Node_Id) return Boolean;
1799 -- Determines whether a constraint uses the discriminant of a record
1800 -- type thus becoming a per-object constraint (POC).
1802 function Is_Known_Limited (Typ : Entity_Id) return Boolean;
1803 -- Typ is the type of the current component, check whether this type is
1804 -- a limited type. Used to validate declaration against that of
1805 -- enclosing record.
1811 function Contains_POC (Constr : Node_Id) return Boolean is
1813 -- Prevent cascaded errors
1815 if Error_Posted (Constr) then
1819 case Nkind (Constr) is
1820 when N_Attribute_Reference =>
1821 return Attribute_Name (Constr) = Name_Access
1822 and then Prefix (Constr) = Scope (Entity (Prefix (Constr)));
1824 when N_Discriminant_Association =>
1825 return Denotes_Discriminant (Expression (Constr));
1827 when N_Identifier =>
1828 return Denotes_Discriminant (Constr);
1830 when N_Index_Or_Discriminant_Constraint =>
1835 IDC := First (Constraints (Constr));
1836 while Present (IDC) loop
1838 -- One per-object constraint is sufficient
1840 if Contains_POC (IDC) then
1851 return Denotes_Discriminant (Low_Bound (Constr))
1853 Denotes_Discriminant (High_Bound (Constr));
1855 when N_Range_Constraint =>
1856 return Denotes_Discriminant (Range_Expression (Constr));
1864 ----------------------
1865 -- Is_Known_Limited --
1866 ----------------------
1868 function Is_Known_Limited (Typ : Entity_Id) return Boolean is
1869 P : constant Entity_Id := Etype (Typ);
1870 R : constant Entity_Id := Root_Type (Typ);
1873 if Is_Limited_Record (Typ) then
1876 -- If the root type is limited (and not a limited interface)
1877 -- so is the current type
1879 elsif Is_Limited_Record (R)
1880 and then (not Is_Interface (R) or else not Is_Limited_Interface (R))
1884 -- Else the type may have a limited interface progenitor, but a
1885 -- limited record parent.
1887 elsif R /= P and then Is_Limited_Record (P) then
1893 end Is_Known_Limited;
1895 -- Start of processing for Analyze_Component_Declaration
1898 Generate_Definition (Id);
1901 if Present (Typ) then
1902 T := Find_Type_Of_Object
1903 (Subtype_Indication (Component_Definition (N)), N);
1905 if not Nkind_In (Typ, N_Identifier, N_Expanded_Name) then
1906 Check_SPARK_05_Restriction ("subtype mark required", Typ);
1909 -- Ada 2005 (AI-230): Access Definition case
1912 pragma Assert (Present
1913 (Access_Definition (Component_Definition (N))));
1915 T := Access_Definition
1917 N => Access_Definition (Component_Definition (N)));
1918 Set_Is_Local_Anonymous_Access (T);
1920 -- Ada 2005 (AI-254)
1922 if Present (Access_To_Subprogram_Definition
1923 (Access_Definition (Component_Definition (N))))
1924 and then Protected_Present (Access_To_Subprogram_Definition
1926 (Component_Definition (N))))
1928 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1932 -- If the subtype is a constrained subtype of the enclosing record,
1933 -- (which must have a partial view) the back-end does not properly
1934 -- handle the recursion. Rewrite the component declaration with an
1935 -- explicit subtype indication, which is acceptable to Gigi. We can copy
1936 -- the tree directly because side effects have already been removed from
1937 -- discriminant constraints.
1939 if Ekind (T) = E_Access_Subtype
1940 and then Is_Entity_Name (Subtype_Indication (Component_Definition (N)))
1941 and then Comes_From_Source (T)
1942 and then Nkind (Parent (T)) = N_Subtype_Declaration
1943 and then Etype (Directly_Designated_Type (T)) = Current_Scope
1946 (Subtype_Indication (Component_Definition (N)),
1947 New_Copy_Tree (Subtype_Indication (Parent (T))));
1948 T := Find_Type_Of_Object
1949 (Subtype_Indication (Component_Definition (N)), N);
1952 -- If the component declaration includes a default expression, then we
1953 -- check that the component is not of a limited type (RM 3.7(5)),
1954 -- and do the special preanalysis of the expression (see section on
1955 -- "Handling of Default and Per-Object Expressions" in the spec of
1959 Check_SPARK_05_Restriction ("default expression is not allowed", E);
1960 Preanalyze_Default_Expression (E, T);
1961 Check_Initialization (T, E);
1963 if Ada_Version >= Ada_2005
1964 and then Ekind (T) = E_Anonymous_Access_Type
1965 and then Etype (E) /= Any_Type
1967 -- Check RM 3.9.2(9): "if the expected type for an expression is
1968 -- an anonymous access-to-specific tagged type, then the object
1969 -- designated by the expression shall not be dynamically tagged
1970 -- unless it is a controlling operand in a call on a dispatching
1973 if Is_Tagged_Type (Directly_Designated_Type (T))
1975 Ekind (Directly_Designated_Type (T)) /= E_Class_Wide_Type
1977 Ekind (Directly_Designated_Type (Etype (E))) =
1981 ("access to specific tagged type required (RM 3.9.2(9))", E);
1984 -- (Ada 2005: AI-230): Accessibility check for anonymous
1987 if Type_Access_Level (Etype (E)) >
1988 Deepest_Type_Access_Level (T)
1991 ("expression has deeper access level than component " &
1992 "(RM 3.10.2 (12.2))", E);
1995 -- The initialization expression is a reference to an access
1996 -- discriminant. The type of the discriminant is always deeper
1997 -- than any access type.
1999 if Ekind (Etype (E)) = E_Anonymous_Access_Type
2000 and then Is_Entity_Name (E)
2001 and then Ekind (Entity (E)) = E_In_Parameter
2002 and then Present (Discriminal_Link (Entity (E)))
2005 ("discriminant has deeper accessibility level than target",
2011 -- The parent type may be a private view with unknown discriminants,
2012 -- and thus unconstrained. Regular components must be constrained.
2014 if not Is_Definite_Subtype (T) and then Chars (Id) /= Name_uParent then
2015 if Is_Class_Wide_Type (T) then
2017 ("class-wide subtype with unknown discriminants" &
2018 " in component declaration",
2019 Subtype_Indication (Component_Definition (N)));
2022 ("unconstrained subtype in component declaration",
2023 Subtype_Indication (Component_Definition (N)));
2026 -- Components cannot be abstract, except for the special case of
2027 -- the _Parent field (case of extending an abstract tagged type)
2029 elsif Is_Abstract_Type (T) and then Chars (Id) /= Name_uParent then
2030 Error_Msg_N ("type of a component cannot be abstract", N);
2034 Set_Is_Aliased (Id, Aliased_Present (Component_Definition (N)));
2036 -- The component declaration may have a per-object constraint, set
2037 -- the appropriate flag in the defining identifier of the subtype.
2039 if Present (Subtype_Indication (Component_Definition (N))) then
2041 Sindic : constant Node_Id :=
2042 Subtype_Indication (Component_Definition (N));
2044 if Nkind (Sindic) = N_Subtype_Indication
2045 and then Present (Constraint (Sindic))
2046 and then Contains_POC (Constraint (Sindic))
2048 Set_Has_Per_Object_Constraint (Id);
2053 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
2054 -- out some static checks.
2056 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
2057 Null_Exclusion_Static_Checks (N);
2060 -- If this component is private (or depends on a private type), flag the
2061 -- record type to indicate that some operations are not available.
2063 P := Private_Component (T);
2067 -- Check for circular definitions
2069 if P = Any_Type then
2070 Set_Etype (Id, Any_Type);
2072 -- There is a gap in the visibility of operations only if the
2073 -- component type is not defined in the scope of the record type.
2075 elsif Scope (P) = Scope (Current_Scope) then
2078 elsif Is_Limited_Type (P) then
2079 Set_Is_Limited_Composite (Current_Scope);
2082 Set_Is_Private_Composite (Current_Scope);
2087 and then Is_Limited_Type (T)
2088 and then Chars (Id) /= Name_uParent
2089 and then Is_Tagged_Type (Current_Scope)
2091 if Is_Derived_Type (Current_Scope)
2092 and then not Is_Known_Limited (Current_Scope)
2095 ("extension of nonlimited type cannot have limited components",
2098 if Is_Interface (Root_Type (Current_Scope)) then
2100 ("\limitedness is not inherited from limited interface", N);
2101 Error_Msg_N ("\add LIMITED to type indication", N);
2104 Explain_Limited_Type (T, N);
2105 Set_Etype (Id, Any_Type);
2106 Set_Is_Limited_Composite (Current_Scope, False);
2108 elsif not Is_Derived_Type (Current_Scope)
2109 and then not Is_Limited_Record (Current_Scope)
2110 and then not Is_Concurrent_Type (Current_Scope)
2113 ("nonlimited tagged type cannot have limited components", N);
2114 Explain_Limited_Type (T, N);
2115 Set_Etype (Id, Any_Type);
2116 Set_Is_Limited_Composite (Current_Scope, False);
2120 -- If the component is an unconstrained task or protected type with
2121 -- discriminants, the component and the enclosing record are limited
2122 -- and the component is constrained by its default values. Compute
2123 -- its actual subtype, else it may be allocated the maximum size by
2124 -- the backend, and possibly overflow.
2126 if Is_Concurrent_Type (T)
2127 and then not Is_Constrained (T)
2128 and then Has_Discriminants (T)
2129 and then not Has_Discriminants (Current_Scope)
2132 Act_T : constant Entity_Id := Build_Default_Subtype (T, N);
2135 Set_Etype (Id, Act_T);
2137 -- Rewrite component definition to use the constrained subtype
2139 Rewrite (Component_Definition (N),
2140 Make_Component_Definition (Loc,
2141 Subtype_Indication => New_Occurrence_Of (Act_T, Loc)));
2145 Set_Original_Record_Component (Id, Id);
2147 if Has_Aspects (N) then
2148 Analyze_Aspect_Specifications (N, Id);
2151 Analyze_Dimension (N);
2152 end Analyze_Component_Declaration;
2154 --------------------------
2155 -- Analyze_Declarations --
2156 --------------------------
2158 procedure Analyze_Declarations (L : List_Id) is
2161 procedure Adjust_Decl;
2162 -- Adjust Decl not to include implicit label declarations, since these
2163 -- have strange Sloc values that result in elaboration check problems.
2164 -- (They have the sloc of the label as found in the source, and that
2165 -- is ahead of the current declarative part).
2167 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id);
2168 -- Determine whether Body_Decl denotes the body of a late controlled
2169 -- primitive (either Initialize, Adjust or Finalize). If this is the
2170 -- case, add a proper spec if the body lacks one. The spec is inserted
2171 -- before Body_Decl and immedately analyzed.
2173 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id);
2174 -- Spec_Id is the entity of a package that may define abstract states.
2175 -- If the states have visible refinement, remove the visibility of each
2176 -- constituent at the end of the package body declarations.
2182 procedure Adjust_Decl is
2184 while Present (Prev (Decl))
2185 and then Nkind (Decl) = N_Implicit_Label_Declaration
2191 --------------------------------------
2192 -- Handle_Late_Controlled_Primitive --
2193 --------------------------------------
2195 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id) is
2196 Body_Spec : constant Node_Id := Specification (Body_Decl);
2197 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2198 Loc : constant Source_Ptr := Sloc (Body_Id);
2199 Params : constant List_Id :=
2200 Parameter_Specifications (Body_Spec);
2202 Spec_Id : Entity_Id;
2206 -- Consider only procedure bodies whose name matches one of the three
2207 -- controlled primitives.
2209 if Nkind (Body_Spec) /= N_Procedure_Specification
2210 or else not Nam_In (Chars (Body_Id), Name_Adjust,
2216 -- A controlled primitive must have exactly one formal which is not
2217 -- an anonymous access type.
2219 elsif List_Length (Params) /= 1 then
2223 Typ := Parameter_Type (First (Params));
2225 if Nkind (Typ) = N_Access_Definition then
2231 -- The type of the formal must be derived from [Limited_]Controlled
2233 if not Is_Controlled (Entity (Typ)) then
2237 -- Check whether a specification exists for this body. We do not
2238 -- analyze the spec of the body in full, because it will be analyzed
2239 -- again when the body is properly analyzed, and we cannot create
2240 -- duplicate entries in the formals chain. We look for an explicit
2241 -- specification because the body may be an overriding operation and
2242 -- an inherited spec may be present.
2244 Spec_Id := Current_Entity (Body_Id);
2246 while Present (Spec_Id) loop
2247 if Ekind_In (Spec_Id, E_Procedure, E_Generic_Procedure)
2248 and then Scope (Spec_Id) = Current_Scope
2249 and then Present (First_Formal (Spec_Id))
2250 and then No (Next_Formal (First_Formal (Spec_Id)))
2251 and then Etype (First_Formal (Spec_Id)) = Entity (Typ)
2252 and then Comes_From_Source (Spec_Id)
2257 Spec_Id := Homonym (Spec_Id);
2260 -- At this point the body is known to be a late controlled primitive.
2261 -- Generate a matching spec and insert it before the body. Note the
2262 -- use of Copy_Separate_Tree - we want an entirely separate semantic
2263 -- tree in this case.
2265 Spec := Copy_Separate_Tree (Body_Spec);
2267 -- Ensure that the subprogram declaration does not inherit the null
2268 -- indicator from the body as we now have a proper spec/body pair.
2270 Set_Null_Present (Spec, False);
2272 Insert_Before_And_Analyze (Body_Decl,
2273 Make_Subprogram_Declaration (Loc, Specification => Spec));
2274 end Handle_Late_Controlled_Primitive;
2276 --------------------------------
2277 -- Remove_Visible_Refinements --
2278 --------------------------------
2280 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id) is
2281 State_Elmt : Elmt_Id;
2283 if Present (Abstract_States (Spec_Id)) then
2284 State_Elmt := First_Elmt (Abstract_States (Spec_Id));
2285 while Present (State_Elmt) loop
2286 Set_Has_Visible_Refinement (Node (State_Elmt), False);
2287 Next_Elmt (State_Elmt);
2290 end Remove_Visible_Refinements;
2294 Context : Node_Id := Empty;
2295 Freeze_From : Entity_Id := Empty;
2296 Next_Decl : Node_Id;
2298 Body_Seen : Boolean := False;
2299 -- Flag set when the first body [stub] is encountered
2301 -- Start of processing for Analyze_Declarations
2304 if Restriction_Check_Required (SPARK_05) then
2305 Check_Later_Vs_Basic_Declarations (L, During_Parsing => False);
2309 while Present (Decl) loop
2311 -- Package spec cannot contain a package declaration in SPARK
2313 if Nkind (Decl) = N_Package_Declaration
2314 and then Nkind (Parent (L)) = N_Package_Specification
2316 Check_SPARK_05_Restriction
2317 ("package specification cannot contain a package declaration",
2321 -- Complete analysis of declaration
2324 Next_Decl := Next (Decl);
2326 if No (Freeze_From) then
2327 Freeze_From := First_Entity (Current_Scope);
2330 -- At the end of a declarative part, freeze remaining entities
2331 -- declared in it. The end of the visible declarations of package
2332 -- specification is not the end of a declarative part if private
2333 -- declarations are present. The end of a package declaration is a
2334 -- freezing point only if it a library package. A task definition or
2335 -- protected type definition is not a freeze point either. Finally,
2336 -- we do not freeze entities in generic scopes, because there is no
2337 -- code generated for them and freeze nodes will be generated for
2340 -- The end of a package instantiation is not a freeze point, but
2341 -- for now we make it one, because the generic body is inserted
2342 -- (currently) immediately after. Generic instantiations will not
2343 -- be a freeze point once delayed freezing of bodies is implemented.
2344 -- (This is needed in any case for early instantiations ???).
2346 if No (Next_Decl) then
2347 if Nkind_In (Parent (L), N_Component_List,
2349 N_Protected_Definition)
2353 elsif Nkind (Parent (L)) /= N_Package_Specification then
2354 if Nkind (Parent (L)) = N_Package_Body then
2355 Freeze_From := First_Entity (Current_Scope);
2358 -- There may have been several freezing points previously,
2359 -- for example object declarations or subprogram bodies, but
2360 -- at the end of a declarative part we check freezing from
2361 -- the beginning, even though entities may already be frozen,
2362 -- in order to perform visibility checks on delayed aspects.
2365 Freeze_All (First_Entity (Current_Scope), Decl);
2366 Freeze_From := Last_Entity (Current_Scope);
2368 elsif Scope (Current_Scope) /= Standard_Standard
2369 and then not Is_Child_Unit (Current_Scope)
2370 and then No (Generic_Parent (Parent (L)))
2374 elsif L /= Visible_Declarations (Parent (L))
2375 or else No (Private_Declarations (Parent (L)))
2376 or else Is_Empty_List (Private_Declarations (Parent (L)))
2379 Freeze_All (First_Entity (Current_Scope), Decl);
2380 Freeze_From := Last_Entity (Current_Scope);
2382 -- At the end of the visible declarations the expressions in
2383 -- aspects of all entities declared so far must be resolved.
2384 -- The entities themselves might be frozen later, and the
2385 -- generated pragmas and attribute definition clauses analyzed
2386 -- in full at that point, but name resolution must take place
2388 -- In addition to being the proper semantics, this is mandatory
2389 -- within generic units, because global name capture requires
2390 -- those expressions to be analyzed, given that the generated
2391 -- pragmas do not appear in the original generic tree.
2393 elsif Serious_Errors_Detected = 0 then
2398 E := First_Entity (Current_Scope);
2399 while Present (E) loop
2400 Resolve_Aspect_Expressions (E);
2406 -- If next node is a body then freeze all types before the body.
2407 -- An exception occurs for some expander-generated bodies. If these
2408 -- are generated at places where in general language rules would not
2409 -- allow a freeze point, then we assume that the expander has
2410 -- explicitly checked that all required types are properly frozen,
2411 -- and we do not cause general freezing here. This special circuit
2412 -- is used when the encountered body is marked as having already
2415 -- In all other cases (bodies that come from source, and expander
2416 -- generated bodies that have not been analyzed yet), freeze all
2417 -- types now. Note that in the latter case, the expander must take
2418 -- care to attach the bodies at a proper place in the tree so as to
2419 -- not cause unwanted freezing at that point.
2421 elsif not Analyzed (Next_Decl) and then Is_Body (Next_Decl) then
2423 -- When a controlled type is frozen, the expander generates stream
2424 -- and controlled type support routines. If the freeze is caused
2425 -- by the stand alone body of Initialize, Adjust and Finalize, the
2426 -- expander will end up using the wrong version of these routines
2427 -- as the body has not been processed yet. To remedy this, detect
2428 -- a late controlled primitive and create a proper spec for it.
2429 -- This ensures that the primitive will override its inherited
2430 -- counterpart before the freeze takes place.
2432 -- If the declaration we just processed is a body, do not attempt
2433 -- to examine Next_Decl as the late primitive idiom can only apply
2434 -- to the first encountered body.
2436 -- The spec of the late primitive is not generated in ASIS mode to
2437 -- ensure a consistent list of primitives that indicates the true
2438 -- semantic structure of the program (which is not relevant when
2439 -- generating executable code.
2441 -- ??? a cleaner approach may be possible and/or this solution
2442 -- could be extended to general-purpose late primitives, TBD.
2444 if not ASIS_Mode and then not Body_Seen and then not Is_Body (Decl)
2448 if Nkind (Next_Decl) = N_Subprogram_Body then
2449 Handle_Late_Controlled_Primitive (Next_Decl);
2454 Freeze_All (Freeze_From, Decl);
2455 Freeze_From := Last_Entity (Current_Scope);
2461 -- Analyze the contracts of packages and their bodies
2464 Context := Parent (L);
2466 if Nkind (Context) = N_Package_Specification then
2468 -- When a package has private declarations, its contract must be
2469 -- analyzed at the end of the said declarations. This way both the
2470 -- analysis and freeze actions are properly synchronized in case
2471 -- of private type use within the contract.
2473 if L = Private_Declarations (Context) then
2474 Analyze_Package_Contract (Defining_Entity (Context));
2476 -- Build the bodies of the default initial condition procedures
2477 -- for all types subject to pragma Default_Initial_Condition.
2478 -- From a purely Ada stand point, this is a freezing activity,
2479 -- however freezing is not available under GNATprove_Mode. To
2480 -- accomodate both scenarios, the bodies are build at the end
2481 -- of private declaration analysis.
2483 Build_Default_Init_Cond_Procedure_Bodies (L);
2485 -- Otherwise the contract is analyzed at the end of the visible
2488 elsif L = Visible_Declarations (Context)
2489 and then No (Private_Declarations (Context))
2491 Analyze_Package_Contract (Defining_Entity (Context));
2494 elsif Nkind (Context) = N_Package_Body then
2495 Analyze_Package_Body_Contract (Defining_Entity (Context));
2498 -- Analyze the contracts of eligible constructs (see below) due to
2499 -- the delayed visibility needs of their aspects and pragmas.
2502 while Present (Decl) loop
2504 -- Entry or subprogram declarations
2506 if Nkind_In (Decl, N_Abstract_Subprogram_Declaration,
2507 N_Entry_Declaration,
2508 N_Generic_Subprogram_Declaration,
2509 N_Subprogram_Declaration)
2511 Analyze_Entry_Or_Subprogram_Contract (Defining_Entity (Decl));
2513 -- Entry or subprogram bodies
2515 elsif Nkind_In (Decl, N_Entry_Body, N_Subprogram_Body) then
2516 Analyze_Entry_Or_Subprogram_Body_Contract
2517 (Defining_Entity (Decl));
2521 elsif Nkind (Decl) = N_Object_Declaration then
2522 Analyze_Object_Contract (Defining_Entity (Decl));
2526 elsif Nkind_In (Decl, N_Protected_Type_Declaration,
2527 N_Single_Protected_Declaration)
2529 Analyze_Protected_Contract (Defining_Entity (Decl));
2531 -- Subprogram body stubs
2533 elsif Nkind (Decl) = N_Subprogram_Body_Stub then
2534 Analyze_Subprogram_Body_Stub_Contract (Defining_Entity (Decl));
2538 elsif Nkind_In (Decl, N_Single_Task_Declaration,
2539 N_Task_Type_Declaration)
2541 Analyze_Task_Contract (Defining_Entity (Decl));
2547 if Nkind (Context) = N_Package_Body then
2549 -- Ensure that all abstract states and objects declared in the
2550 -- state space of a package body are utilized as constituents.
2552 Check_Unused_Body_States (Defining_Entity (Context));
2554 -- State refinements are visible upto the end the of the package
2555 -- body declarations. Hide the state refinements from visibility
2556 -- to restore the original state conditions.
2558 Remove_Visible_Refinements (Corresponding_Spec (Context));
2561 end Analyze_Declarations;
2563 -----------------------------------
2564 -- Analyze_Full_Type_Declaration --
2565 -----------------------------------
2567 procedure Analyze_Full_Type_Declaration (N : Node_Id) is
2568 Def : constant Node_Id := Type_Definition (N);
2569 Def_Id : constant Entity_Id := Defining_Identifier (N);
2573 Is_Remote : constant Boolean :=
2574 (Is_Remote_Types (Current_Scope)
2575 or else Is_Remote_Call_Interface (Current_Scope))
2576 and then not (In_Private_Part (Current_Scope)
2577 or else In_Package_Body (Current_Scope));
2579 procedure Check_Nonoverridable_Aspects;
2580 -- Apply the rule in RM 13.1.1(18.4/4) on iterator aspects that cannot
2581 -- be overridden, and can only be confirmed on derivation.
2583 procedure Check_Ops_From_Incomplete_Type;
2584 -- If there is a tagged incomplete partial view of the type, traverse
2585 -- the primitives of the incomplete view and change the type of any
2586 -- controlling formals and result to indicate the full view. The
2587 -- primitives will be added to the full type's primitive operations
2588 -- list later in Sem_Disp.Check_Operation_From_Incomplete_Type (which
2589 -- is called from Process_Incomplete_Dependents).
2591 ----------------------------------
2592 -- Check_Nonoverridable_Aspects --
2593 ----------------------------------
2595 procedure Check_Nonoverridable_Aspects is
2596 Prev_Aspects : constant List_Id :=
2597 Aspect_Specifications (Parent (Def_Id));
2598 Par_Type : Entity_Id;
2600 function Has_Aspect_Spec
2602 Aspect_Name : Name_Id) return Boolean;
2603 -- Check whether a list of aspect specifications includes an entry
2604 -- for a specific aspect. The list is either that of a partial or
2607 ---------------------
2608 -- Has_Aspect_Spec --
2609 ---------------------
2611 function Has_Aspect_Spec
2613 Aspect_Name : Name_Id) return Boolean
2617 Spec := First (Specs);
2618 while Present (Spec) loop
2619 if Chars (Identifier (Spec)) = Aspect_Name then
2625 end Has_Aspect_Spec;
2627 -- Start of processing for Check_Nonoverridable_Aspects
2631 -- Get parent type of derived type. Note that Prev is the entity
2632 -- in the partial declaration, but its contents are now those of
2633 -- full view, while Def_Id reflects the partial view.
2635 if Is_Private_Type (Def_Id) then
2636 Par_Type := Etype (Full_View (Def_Id));
2638 Par_Type := Etype (Def_Id);
2641 -- If there is an inherited Implicit_Dereference, verify that it is
2642 -- made explicit in the partial view.
2644 if Has_Discriminants (Base_Type (Par_Type))
2645 and then Nkind (Parent (Prev)) = N_Full_Type_Declaration
2646 and then Present (Discriminant_Specifications (Parent (Prev)))
2647 and then Present (Get_Reference_Discriminant (Par_Type))
2650 not Has_Aspect_Spec (Prev_Aspects, Name_Implicit_Dereference)
2653 ("type does not inherit implicit dereference", Prev);
2656 -- If one of the views has the aspect specified, verify that it
2657 -- is consistent with that of the parent.
2660 Par_Discr : constant Entity_Id :=
2661 Get_Reference_Discriminant (Par_Type);
2662 Cur_Discr : constant Entity_Id :=
2663 Get_Reference_Discriminant (Prev);
2665 if Corresponding_Discriminant (Cur_Discr) /= Par_Discr then
2666 Error_Msg_N ("aspect incosistent with that of parent", N);
2672 -- TBD : other nonoverridable aspects.
2673 end Check_Nonoverridable_Aspects;
2675 ------------------------------------
2676 -- Check_Ops_From_Incomplete_Type --
2677 ------------------------------------
2679 procedure Check_Ops_From_Incomplete_Type is
2686 and then Ekind (Prev) = E_Incomplete_Type
2687 and then Is_Tagged_Type (Prev)
2688 and then Is_Tagged_Type (T)
2690 Elmt := First_Elmt (Primitive_Operations (Prev));
2691 while Present (Elmt) loop
2694 Formal := First_Formal (Op);
2695 while Present (Formal) loop
2696 if Etype (Formal) = Prev then
2697 Set_Etype (Formal, T);
2700 Next_Formal (Formal);
2703 if Etype (Op) = Prev then
2710 end Check_Ops_From_Incomplete_Type;
2712 -- Start of processing for Analyze_Full_Type_Declaration
2715 Prev := Find_Type_Name (N);
2717 -- The full view, if present, now points to the current type. If there
2718 -- is an incomplete partial view, set a link to it, to simplify the
2719 -- retrieval of primitive operations of the type.
2721 -- Ada 2005 (AI-50217): If the type was previously decorated when
2722 -- imported through a LIMITED WITH clause, it appears as incomplete
2723 -- but has no full view.
2725 if Ekind (Prev) = E_Incomplete_Type
2726 and then Present (Full_View (Prev))
2728 T := Full_View (Prev);
2729 Set_Incomplete_View (N, Parent (Prev));
2734 Set_Is_Pure (T, Is_Pure (Current_Scope));
2736 -- We set the flag Is_First_Subtype here. It is needed to set the
2737 -- corresponding flag for the Implicit class-wide-type created
2738 -- during tagged types processing.
2740 Set_Is_First_Subtype (T, True);
2742 -- Only composite types other than array types are allowed to have
2747 -- For derived types, the rule will be checked once we've figured
2748 -- out the parent type.
2750 when N_Derived_Type_Definition =>
2753 -- For record types, discriminants are allowed, unless we are in
2756 when N_Record_Definition =>
2757 if Present (Discriminant_Specifications (N)) then
2758 Check_SPARK_05_Restriction
2759 ("discriminant type is not allowed",
2761 (First (Discriminant_Specifications (N))));
2765 if Present (Discriminant_Specifications (N)) then
2767 ("elementary or array type cannot have discriminants",
2769 (First (Discriminant_Specifications (N))));
2773 -- Elaborate the type definition according to kind, and generate
2774 -- subsidiary (implicit) subtypes where needed. We skip this if it was
2775 -- already done (this happens during the reanalysis that follows a call
2776 -- to the high level optimizer).
2778 if not Analyzed (T) then
2782 when N_Access_To_Subprogram_Definition =>
2783 Access_Subprogram_Declaration (T, Def);
2785 -- If this is a remote access to subprogram, we must create the
2786 -- equivalent fat pointer type, and related subprograms.
2789 Process_Remote_AST_Declaration (N);
2792 -- Validate categorization rule against access type declaration
2793 -- usually a violation in Pure unit, Shared_Passive unit.
2795 Validate_Access_Type_Declaration (T, N);
2797 when N_Access_To_Object_Definition =>
2798 Access_Type_Declaration (T, Def);
2800 -- Validate categorization rule against access type declaration
2801 -- usually a violation in Pure unit, Shared_Passive unit.
2803 Validate_Access_Type_Declaration (T, N);
2805 -- If we are in a Remote_Call_Interface package and define a
2806 -- RACW, then calling stubs and specific stream attributes
2810 and then Is_Remote_Access_To_Class_Wide_Type (Def_Id)
2812 Add_RACW_Features (Def_Id);
2815 when N_Array_Type_Definition =>
2816 Array_Type_Declaration (T, Def);
2818 when N_Derived_Type_Definition =>
2819 Derived_Type_Declaration (T, N, T /= Def_Id);
2821 when N_Enumeration_Type_Definition =>
2822 Enumeration_Type_Declaration (T, Def);
2824 when N_Floating_Point_Definition =>
2825 Floating_Point_Type_Declaration (T, Def);
2827 when N_Decimal_Fixed_Point_Definition =>
2828 Decimal_Fixed_Point_Type_Declaration (T, Def);
2830 when N_Ordinary_Fixed_Point_Definition =>
2831 Ordinary_Fixed_Point_Type_Declaration (T, Def);
2833 when N_Signed_Integer_Type_Definition =>
2834 Signed_Integer_Type_Declaration (T, Def);
2836 when N_Modular_Type_Definition =>
2837 Modular_Type_Declaration (T, Def);
2839 when N_Record_Definition =>
2840 Record_Type_Declaration (T, N, Prev);
2842 -- If declaration has a parse error, nothing to elaborate.
2848 raise Program_Error;
2853 if Etype (T) = Any_Type then
2857 -- Controlled type is not allowed in SPARK
2859 if Is_Visibly_Controlled (T) then
2860 Check_SPARK_05_Restriction ("controlled type is not allowed", N);
2863 -- A type declared within a Ghost region is automatically Ghost
2864 -- (SPARK RM 6.9(2)).
2866 if Ghost_Mode > None then
2867 Set_Is_Ghost_Entity (T);
2870 -- Some common processing for all types
2872 Set_Depends_On_Private (T, Has_Private_Component (T));
2873 Check_Ops_From_Incomplete_Type;
2875 -- Both the declared entity, and its anonymous base type if one was
2876 -- created, need freeze nodes allocated.
2879 B : constant Entity_Id := Base_Type (T);
2882 -- In the case where the base type differs from the first subtype, we
2883 -- pre-allocate a freeze node, and set the proper link to the first
2884 -- subtype. Freeze_Entity will use this preallocated freeze node when
2885 -- it freezes the entity.
2887 -- This does not apply if the base type is a generic type, whose
2888 -- declaration is independent of the current derived definition.
2890 if B /= T and then not Is_Generic_Type (B) then
2891 Ensure_Freeze_Node (B);
2892 Set_First_Subtype_Link (Freeze_Node (B), T);
2895 -- A type that is imported through a limited_with clause cannot
2896 -- generate any code, and thus need not be frozen. However, an access
2897 -- type with an imported designated type needs a finalization list,
2898 -- which may be referenced in some other package that has non-limited
2899 -- visibility on the designated type. Thus we must create the
2900 -- finalization list at the point the access type is frozen, to
2901 -- prevent unsatisfied references at link time.
2903 if not From_Limited_With (T) or else Is_Access_Type (T) then
2904 Set_Has_Delayed_Freeze (T);
2908 -- Case where T is the full declaration of some private type which has
2909 -- been swapped in Defining_Identifier (N).
2911 if T /= Def_Id and then Is_Private_Type (Def_Id) then
2912 Process_Full_View (N, T, Def_Id);
2914 -- Record the reference. The form of this is a little strange, since
2915 -- the full declaration has been swapped in. So the first parameter
2916 -- here represents the entity to which a reference is made which is
2917 -- the "real" entity, i.e. the one swapped in, and the second
2918 -- parameter provides the reference location.
2920 -- Also, we want to kill Has_Pragma_Unreferenced temporarily here
2921 -- since we don't want a complaint about the full type being an
2922 -- unwanted reference to the private type
2925 B : constant Boolean := Has_Pragma_Unreferenced (T);
2927 Set_Has_Pragma_Unreferenced (T, False);
2928 Generate_Reference (T, T, 'c');
2929 Set_Has_Pragma_Unreferenced (T, B);
2932 Set_Completion_Referenced (Def_Id);
2934 -- For completion of incomplete type, process incomplete dependents
2935 -- and always mark the full type as referenced (it is the incomplete
2936 -- type that we get for any real reference).
2938 elsif Ekind (Prev) = E_Incomplete_Type then
2939 Process_Incomplete_Dependents (N, T, Prev);
2940 Generate_Reference (Prev, Def_Id, 'c');
2941 Set_Completion_Referenced (Def_Id);
2943 -- If not private type or incomplete type completion, this is a real
2944 -- definition of a new entity, so record it.
2947 Generate_Definition (Def_Id);
2950 -- Propagate any pending access types whose finalization masters need to
2951 -- be fully initialized from the partial to the full view. Guard against
2952 -- an illegal full view that remains unanalyzed.
2954 if Is_Type (Def_Id) and then Is_Incomplete_Or_Private_Type (Prev) then
2955 Set_Pending_Access_Types (Def_Id, Pending_Access_Types (Prev));
2958 if Chars (Scope (Def_Id)) = Name_System
2959 and then Chars (Def_Id) = Name_Address
2960 and then Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (N)))
2962 Set_Is_Descendent_Of_Address (Def_Id);
2963 Set_Is_Descendent_Of_Address (Base_Type (Def_Id));
2964 Set_Is_Descendent_Of_Address (Prev);
2967 Set_Optimize_Alignment_Flags (Def_Id);
2968 Check_Eliminated (Def_Id);
2970 -- If the declaration is a completion and aspects are present, apply
2971 -- them to the entity for the type which is currently the partial
2972 -- view, but which is the one that will be frozen.
2974 if Has_Aspects (N) then
2976 -- In most cases the partial view is a private type, and both views
2977 -- appear in different declarative parts. In the unusual case where
2978 -- the partial view is incomplete, perform the analysis on the
2979 -- full view, to prevent freezing anomalies with the corresponding
2980 -- class-wide type, which otherwise might be frozen before the
2981 -- dispatch table is built.
2984 and then Ekind (Prev) /= E_Incomplete_Type
2986 Analyze_Aspect_Specifications (N, Prev);
2991 Analyze_Aspect_Specifications (N, Def_Id);
2995 if Is_Derived_Type (Prev)
2996 and then Def_Id /= Prev
2998 Check_Nonoverridable_Aspects;
3000 end Analyze_Full_Type_Declaration;
3002 ----------------------------------
3003 -- Analyze_Incomplete_Type_Decl --
3004 ----------------------------------
3006 procedure Analyze_Incomplete_Type_Decl (N : Node_Id) is
3007 F : constant Boolean := Is_Pure (Current_Scope);
3011 Check_SPARK_05_Restriction ("incomplete type is not allowed", N);
3013 Generate_Definition (Defining_Identifier (N));
3015 -- Process an incomplete declaration. The identifier must not have been
3016 -- declared already in the scope. However, an incomplete declaration may
3017 -- appear in the private part of a package, for a private type that has
3018 -- already been declared.
3020 -- In this case, the discriminants (if any) must match
3022 T := Find_Type_Name (N);
3024 Set_Ekind (T, E_Incomplete_Type);
3025 Init_Size_Align (T);
3026 Set_Is_First_Subtype (T, True);
3029 -- An incomplete type declared within a Ghost region is automatically
3030 -- Ghost (SPARK RM 6.9(2)).
3032 if Ghost_Mode > None then
3033 Set_Is_Ghost_Entity (T);
3036 -- Ada 2005 (AI-326): Minimum decoration to give support to tagged
3037 -- incomplete types.
3039 if Tagged_Present (N) then
3040 Set_Is_Tagged_Type (T, True);
3041 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
3042 Make_Class_Wide_Type (T);
3043 Set_Direct_Primitive_Operations (T, New_Elmt_List);
3046 Set_Stored_Constraint (T, No_Elist);
3048 if Present (Discriminant_Specifications (N)) then
3050 Process_Discriminants (N);
3054 -- If the type has discriminants, nontrivial subtypes may be declared
3055 -- before the full view of the type. The full views of those subtypes
3056 -- will be built after the full view of the type.
3058 Set_Private_Dependents (T, New_Elmt_List);
3060 end Analyze_Incomplete_Type_Decl;
3062 -----------------------------------
3063 -- Analyze_Interface_Declaration --
3064 -----------------------------------
3066 procedure Analyze_Interface_Declaration (T : Entity_Id; Def : Node_Id) is
3067 CW : constant Entity_Id := Class_Wide_Type (T);
3070 Set_Is_Tagged_Type (T);
3071 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
3073 Set_Is_Limited_Record (T, Limited_Present (Def)
3074 or else Task_Present (Def)
3075 or else Protected_Present (Def)
3076 or else Synchronized_Present (Def));
3078 -- Type is abstract if full declaration carries keyword, or if previous
3079 -- partial view did.
3081 Set_Is_Abstract_Type (T);
3082 Set_Is_Interface (T);
3084 -- Type is a limited interface if it includes the keyword limited, task,
3085 -- protected, or synchronized.
3087 Set_Is_Limited_Interface
3088 (T, Limited_Present (Def)
3089 or else Protected_Present (Def)
3090 or else Synchronized_Present (Def)
3091 or else Task_Present (Def));
3093 Set_Interfaces (T, New_Elmt_List);
3094 Set_Direct_Primitive_Operations (T, New_Elmt_List);
3096 -- Complete the decoration of the class-wide entity if it was already
3097 -- built (i.e. during the creation of the limited view)
3099 if Present (CW) then
3100 Set_Is_Interface (CW);
3101 Set_Is_Limited_Interface (CW, Is_Limited_Interface (T));
3104 -- Check runtime support for synchronized interfaces
3106 if (Is_Task_Interface (T)
3107 or else Is_Protected_Interface (T)
3108 or else Is_Synchronized_Interface (T))
3109 and then not RTE_Available (RE_Select_Specific_Data)
3111 Error_Msg_CRT ("synchronized interfaces", T);
3113 end Analyze_Interface_Declaration;
3115 -----------------------------
3116 -- Analyze_Itype_Reference --
3117 -----------------------------
3119 -- Nothing to do. This node is placed in the tree only for the benefit of
3120 -- back end processing, and has no effect on the semantic processing.
3122 procedure Analyze_Itype_Reference (N : Node_Id) is
3124 pragma Assert (Is_Itype (Itype (N)));
3126 end Analyze_Itype_Reference;
3128 --------------------------------
3129 -- Analyze_Number_Declaration --
3130 --------------------------------
3132 procedure Analyze_Number_Declaration (N : Node_Id) is
3133 E : constant Node_Id := Expression (N);
3134 Id : constant Entity_Id := Defining_Identifier (N);
3135 Index : Interp_Index;
3140 Generate_Definition (Id);
3143 -- A number declared within a Ghost region is automatically Ghost
3144 -- (SPARK RM 6.9(2)).
3146 if Ghost_Mode > None then
3147 Set_Is_Ghost_Entity (Id);
3150 -- This is an optimization of a common case of an integer literal
3152 if Nkind (E) = N_Integer_Literal then
3153 Set_Is_Static_Expression (E, True);
3154 Set_Etype (E, Universal_Integer);
3156 Set_Etype (Id, Universal_Integer);
3157 Set_Ekind (Id, E_Named_Integer);
3158 Set_Is_Frozen (Id, True);
3162 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3164 -- Process expression, replacing error by integer zero, to avoid
3165 -- cascaded errors or aborts further along in the processing
3167 -- Replace Error by integer zero, which seems least likely to cause
3171 Rewrite (E, Make_Integer_Literal (Sloc (E), Uint_0));
3172 Set_Error_Posted (E);
3177 -- Verify that the expression is static and numeric. If
3178 -- the expression is overloaded, we apply the preference
3179 -- rule that favors root numeric types.
3181 if not Is_Overloaded (E) then
3183 if Has_Dynamic_Predicate_Aspect (T) then
3185 ("subtype has dynamic predicate, "
3186 & "not allowed in number declaration", N);
3192 Get_First_Interp (E, Index, It);
3193 while Present (It.Typ) loop
3194 if (Is_Integer_Type (It.Typ) or else Is_Real_Type (It.Typ))
3195 and then (Scope (Base_Type (It.Typ))) = Standard_Standard
3197 if T = Any_Type then
3200 elsif It.Typ = Universal_Real
3202 It.Typ = Universal_Integer
3204 -- Choose universal interpretation over any other
3211 Get_Next_Interp (Index, It);
3215 if Is_Integer_Type (T) then
3217 Set_Etype (Id, Universal_Integer);
3218 Set_Ekind (Id, E_Named_Integer);
3220 elsif Is_Real_Type (T) then
3222 -- Because the real value is converted to universal_real, this is a
3223 -- legal context for a universal fixed expression.
3225 if T = Universal_Fixed then
3227 Loc : constant Source_Ptr := Sloc (N);
3228 Conv : constant Node_Id := Make_Type_Conversion (Loc,
3230 New_Occurrence_Of (Universal_Real, Loc),
3231 Expression => Relocate_Node (E));
3238 elsif T = Any_Fixed then
3239 Error_Msg_N ("illegal context for mixed mode operation", E);
3241 -- Expression is of the form : universal_fixed * integer. Try to
3242 -- resolve as universal_real.
3244 T := Universal_Real;
3249 Set_Etype (Id, Universal_Real);
3250 Set_Ekind (Id, E_Named_Real);
3253 Wrong_Type (E, Any_Numeric);
3257 Set_Ekind (Id, E_Constant);
3258 Set_Never_Set_In_Source (Id, True);
3259 Set_Is_True_Constant (Id, True);
3263 if Nkind_In (E, N_Integer_Literal, N_Real_Literal) then
3264 Set_Etype (E, Etype (Id));
3267 if not Is_OK_Static_Expression (E) then
3268 Flag_Non_Static_Expr
3269 ("non-static expression used in number declaration!", E);
3270 Rewrite (E, Make_Integer_Literal (Sloc (N), 1));
3271 Set_Etype (E, Any_Type);
3274 Analyze_Dimension (N);
3275 end Analyze_Number_Declaration;
3277 --------------------------------
3278 -- Analyze_Object_Declaration --
3279 --------------------------------
3281 procedure Analyze_Object_Declaration (N : Node_Id) is
3282 Loc : constant Source_Ptr := Sloc (N);
3283 Id : constant Entity_Id := Defining_Identifier (N);
3287 E : Node_Id := Expression (N);
3288 -- E is set to Expression (N) throughout this routine. When
3289 -- Expression (N) is modified, E is changed accordingly.
3291 Prev_Entity : Entity_Id := Empty;
3293 function Count_Tasks (T : Entity_Id) return Uint;
3294 -- This function is called when a non-generic library level object of a
3295 -- task type is declared. Its function is to count the static number of
3296 -- tasks declared within the type (it is only called if Has_Task is set
3297 -- for T). As a side effect, if an array of tasks with non-static bounds
3298 -- or a variant record type is encountered, Check_Restriction is called
3299 -- indicating the count is unknown.
3301 function Delayed_Aspect_Present return Boolean;
3302 -- If the declaration has an expression that is an aggregate, and it
3303 -- has aspects that require delayed analysis, the resolution of the
3304 -- aggregate must be deferred to the freeze point of the objet. This
3305 -- special processing was created for address clauses, but it must
3306 -- also apply to Alignment. This must be done before the aspect
3307 -- specifications are analyzed because we must handle the aggregate
3308 -- before the analysis of the object declaration is complete.
3310 -- Any other relevant delayed aspects on object declarations ???
3316 function Count_Tasks (T : Entity_Id) return Uint is
3322 if Is_Task_Type (T) then
3325 elsif Is_Record_Type (T) then
3326 if Has_Discriminants (T) then
3327 Check_Restriction (Max_Tasks, N);
3332 C := First_Component (T);
3333 while Present (C) loop
3334 V := V + Count_Tasks (Etype (C));
3341 elsif Is_Array_Type (T) then
3342 X := First_Index (T);
3343 V := Count_Tasks (Component_Type (T));
3344 while Present (X) loop
3347 if not Is_OK_Static_Subtype (C) then
3348 Check_Restriction (Max_Tasks, N);
3351 V := V * (UI_Max (Uint_0,
3352 Expr_Value (Type_High_Bound (C)) -
3353 Expr_Value (Type_Low_Bound (C)) + Uint_1));
3366 ----------------------------
3367 -- Delayed_Aspect_Present --
3368 ----------------------------
3370 function Delayed_Aspect_Present return Boolean is
3375 if Present (Aspect_Specifications (N)) then
3376 A := First (Aspect_Specifications (N));
3377 A_Id := Get_Aspect_Id (Chars (Identifier (A)));
3378 while Present (A) loop
3379 if A_Id = Aspect_Alignment or else A_Id = Aspect_Address then
3388 end Delayed_Aspect_Present;
3392 Save_Ghost_Mode : constant Ghost_Mode_Type := Ghost_Mode;
3394 -- Start of processing for Analyze_Object_Declaration
3397 -- There are three kinds of implicit types generated by an
3398 -- object declaration:
3400 -- 1. Those generated by the original Object Definition
3402 -- 2. Those generated by the Expression
3404 -- 3. Those used to constrain the Object Definition with the
3405 -- expression constraints when the definition is unconstrained.
3407 -- They must be generated in this order to avoid order of elaboration
3408 -- issues. Thus the first step (after entering the name) is to analyze
3409 -- the object definition.
3411 if Constant_Present (N) then
3412 Prev_Entity := Current_Entity_In_Scope (Id);
3414 if Present (Prev_Entity)
3416 -- If the homograph is an implicit subprogram, it is overridden
3417 -- by the current declaration.
3419 ((Is_Overloadable (Prev_Entity)
3420 and then Is_Inherited_Operation (Prev_Entity))
3422 -- The current object is a discriminal generated for an entry
3423 -- family index. Even though the index is a constant, in this
3424 -- particular context there is no true constant redeclaration.
3425 -- Enter_Name will handle the visibility.
3428 (Is_Discriminal (Id)
3429 and then Ekind (Discriminal_Link (Id)) =
3430 E_Entry_Index_Parameter)
3432 -- The current object is the renaming for a generic declared
3433 -- within the instance.
3436 (Ekind (Prev_Entity) = E_Package
3437 and then Nkind (Parent (Prev_Entity)) =
3438 N_Package_Renaming_Declaration
3439 and then not Comes_From_Source (Prev_Entity)
3441 Is_Generic_Instance (Renamed_Entity (Prev_Entity))))
3443 Prev_Entity := Empty;
3447 -- The object declaration is Ghost when it is subject to pragma Ghost or
3448 -- completes a deferred Ghost constant. Set the mode now to ensure that
3449 -- any nodes generated during analysis and expansion are properly marked
3452 Set_Ghost_Mode (N, Prev_Entity);
3454 if Present (Prev_Entity) then
3455 Constant_Redeclaration (Id, N, T);
3457 Generate_Reference (Prev_Entity, Id, 'c');
3458 Set_Completion_Referenced (Id);
3460 if Error_Posted (N) then
3462 -- Type mismatch or illegal redeclaration, Do not analyze
3463 -- expression to avoid cascaded errors.
3465 T := Find_Type_Of_Object (Object_Definition (N), N);
3467 Set_Ekind (Id, E_Variable);
3471 -- In the normal case, enter identifier at the start to catch premature
3472 -- usage in the initialization expression.
3475 Generate_Definition (Id);
3478 Mark_Coextensions (N, Object_Definition (N));
3480 T := Find_Type_Of_Object (Object_Definition (N), N);
3482 if Nkind (Object_Definition (N)) = N_Access_Definition
3484 (Access_To_Subprogram_Definition (Object_Definition (N)))
3485 and then Protected_Present
3486 (Access_To_Subprogram_Definition (Object_Definition (N)))
3488 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
3491 if Error_Posted (Id) then
3493 Set_Ekind (Id, E_Variable);
3498 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
3499 -- out some static checks
3501 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
3503 -- In case of aggregates we must also take care of the correct
3504 -- initialization of nested aggregates bug this is done at the
3505 -- point of the analysis of the aggregate (see sem_aggr.adb).
3507 if Present (Expression (N))
3508 and then Nkind (Expression (N)) = N_Aggregate
3514 Save_Typ : constant Entity_Id := Etype (Id);
3516 Set_Etype (Id, T); -- Temp. decoration for static checks
3517 Null_Exclusion_Static_Checks (N);
3518 Set_Etype (Id, Save_Typ);
3523 -- Object is marked pure if it is in a pure scope
3525 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3527 -- If deferred constant, make sure context is appropriate. We detect
3528 -- a deferred constant as a constant declaration with no expression.
3529 -- A deferred constant can appear in a package body if its completion
3530 -- is by means of an interface pragma.
3532 if Constant_Present (N) and then No (E) then
3534 -- A deferred constant may appear in the declarative part of the
3535 -- following constructs:
3539 -- extended return statements
3542 -- subprogram bodies
3545 -- When declared inside a package spec, a deferred constant must be
3546 -- completed by a full constant declaration or pragma Import. In all
3547 -- other cases, the only proper completion is pragma Import. Extended
3548 -- return statements are flagged as invalid contexts because they do
3549 -- not have a declarative part and so cannot accommodate the pragma.
3551 if Ekind (Current_Scope) = E_Return_Statement then
3553 ("invalid context for deferred constant declaration (RM 7.4)",
3556 ("\declaration requires an initialization expression",
3558 Set_Constant_Present (N, False);
3560 -- In Ada 83, deferred constant must be of private type
3562 elsif not Is_Private_Type (T) then
3563 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
3565 ("(Ada 83) deferred constant must be private type", N);
3569 -- If not a deferred constant, then the object declaration freezes
3570 -- its type, unless the object is of an anonymous type and has delayed
3571 -- aspects. In that case the type is frozen when the object itself is.
3574 Check_Fully_Declared (T, N);
3576 if Has_Delayed_Aspects (Id)
3577 and then Is_Array_Type (T)
3578 and then Is_Itype (T)
3580 Set_Has_Delayed_Freeze (T);
3582 Freeze_Before (N, T);
3586 -- If the object was created by a constrained array definition, then
3587 -- set the link in both the anonymous base type and anonymous subtype
3588 -- that are built to represent the array type to point to the object.
3590 if Nkind (Object_Definition (Declaration_Node (Id))) =
3591 N_Constrained_Array_Definition
3593 Set_Related_Array_Object (T, Id);
3594 Set_Related_Array_Object (Base_Type (T), Id);
3597 -- Special checks for protected objects not at library level
3599 if Is_Protected_Type (T)
3600 and then not Is_Library_Level_Entity (Id)
3602 Check_Restriction (No_Local_Protected_Objects, Id);
3604 -- Protected objects with interrupt handlers must be at library level
3606 -- Ada 2005: This test is not needed (and the corresponding clause
3607 -- in the RM is removed) because accessibility checks are sufficient
3608 -- to make handlers not at the library level illegal.
3610 -- AI05-0303: The AI is in fact a binding interpretation, and thus
3611 -- applies to the '95 version of the language as well.
3613 if Has_Interrupt_Handler (T) and then Ada_Version < Ada_95 then
3615 ("interrupt object can only be declared at library level", Id);
3619 -- The actual subtype of the object is the nominal subtype, unless
3620 -- the nominal one is unconstrained and obtained from the expression.
3624 -- These checks should be performed before the initialization expression
3625 -- is considered, so that the Object_Definition node is still the same
3626 -- as in source code.
3628 -- In SPARK, the nominal subtype is always given by a subtype mark
3629 -- and must not be unconstrained. (The only exception to this is the
3630 -- acceptance of declarations of constants of type String.)
3632 if not Nkind_In (Object_Definition (N), N_Expanded_Name, N_Identifier)
3634 Check_SPARK_05_Restriction
3635 ("subtype mark required", Object_Definition (N));
3637 elsif Is_Array_Type (T)
3638 and then not Is_Constrained (T)
3639 and then T /= Standard_String
3641 Check_SPARK_05_Restriction
3642 ("subtype mark of constrained type expected",
3643 Object_Definition (N));
3646 -- There are no aliased objects in SPARK
3648 if Aliased_Present (N) then
3649 Check_SPARK_05_Restriction ("aliased object is not allowed", N);
3652 -- Process initialization expression if present and not in error
3654 if Present (E) and then E /= Error then
3656 -- Generate an error in case of CPP class-wide object initialization.
3657 -- Required because otherwise the expansion of the class-wide
3658 -- assignment would try to use 'size to initialize the object
3659 -- (primitive that is not available in CPP tagged types).
3661 if Is_Class_Wide_Type (Act_T)
3663 (Is_CPP_Class (Root_Type (Etype (Act_T)))
3665 (Present (Full_View (Root_Type (Etype (Act_T))))
3667 Is_CPP_Class (Full_View (Root_Type (Etype (Act_T))))))
3670 ("predefined assignment not available for 'C'P'P tagged types",
3674 Mark_Coextensions (N, E);
3677 -- In case of errors detected in the analysis of the expression,
3678 -- decorate it with the expected type to avoid cascaded errors
3680 if No (Etype (E)) then
3684 -- If an initialization expression is present, then we set the
3685 -- Is_True_Constant flag. It will be reset if this is a variable
3686 -- and it is indeed modified.
3688 Set_Is_True_Constant (Id, True);
3690 -- If we are analyzing a constant declaration, set its completion
3691 -- flag after analyzing and resolving the expression.
3693 if Constant_Present (N) then
3694 Set_Has_Completion (Id);
3697 -- Set type and resolve (type may be overridden later on). Note:
3698 -- Ekind (Id) must still be E_Void at this point so that incorrect
3699 -- early usage within E is properly diagnosed.
3703 -- If the expression is an aggregate we must look ahead to detect
3704 -- the possible presence of an address clause, and defer resolution
3705 -- and expansion of the aggregate to the freeze point of the entity.
3707 -- This is not always legal because the aggregate may contain other
3708 -- references that need freezing, e.g. references to other entities
3709 -- with address clauses. In any case, when compiling with -gnatI the
3710 -- presence of the address clause must be ignored.
3712 if Comes_From_Source (N)
3713 and then Expander_Active
3714 and then Nkind (E) = N_Aggregate
3716 ((Present (Following_Address_Clause (N))
3717 and then not Ignore_Rep_Clauses)
3718 or else Delayed_Aspect_Present)
3726 -- No further action needed if E is a call to an inlined function
3727 -- which returns an unconstrained type and it has been expanded into
3728 -- a procedure call. In that case N has been replaced by an object
3729 -- declaration without initializing expression and it has been
3730 -- analyzed (see Expand_Inlined_Call).
3732 if Back_End_Inlining
3733 and then Expander_Active
3734 and then Nkind (E) = N_Function_Call
3735 and then Nkind (Name (E)) in N_Has_Entity
3736 and then Is_Inlined (Entity (Name (E)))
3737 and then not Is_Constrained (Etype (E))
3738 and then Analyzed (N)
3739 and then No (Expression (N))
3741 Ghost_Mode := Save_Ghost_Mode;
3745 -- If E is null and has been replaced by an N_Raise_Constraint_Error
3746 -- node (which was marked already-analyzed), we need to set the type
3747 -- to something other than Any_Access in order to keep gigi happy.
3749 if Etype (E) = Any_Access then
3753 -- If the object is an access to variable, the initialization
3754 -- expression cannot be an access to constant.
3756 if Is_Access_Type (T)
3757 and then not Is_Access_Constant (T)
3758 and then Is_Access_Type (Etype (E))
3759 and then Is_Access_Constant (Etype (E))
3762 ("access to variable cannot be initialized with an "
3763 & "access-to-constant expression", E);
3766 if not Assignment_OK (N) then
3767 Check_Initialization (T, E);
3770 Check_Unset_Reference (E);
3772 -- If this is a variable, then set current value. If this is a
3773 -- declared constant of a scalar type with a static expression,
3774 -- indicate that it is always valid.
3776 if not Constant_Present (N) then
3777 if Compile_Time_Known_Value (E) then
3778 Set_Current_Value (Id, E);
3781 elsif Is_Scalar_Type (T) and then Is_OK_Static_Expression (E) then
3782 Set_Is_Known_Valid (Id);
3785 -- Deal with setting of null flags
3787 if Is_Access_Type (T) then
3788 if Known_Non_Null (E) then
3789 Set_Is_Known_Non_Null (Id, True);
3790 elsif Known_Null (E) and then not Can_Never_Be_Null (Id) then
3791 Set_Is_Known_Null (Id, True);
3795 -- Check incorrect use of dynamically tagged expressions
3797 if Is_Tagged_Type (T) then
3798 Check_Dynamically_Tagged_Expression
3804 Apply_Scalar_Range_Check (E, T);
3805 Apply_Static_Length_Check (E, T);
3807 if Nkind (Original_Node (N)) = N_Object_Declaration
3808 and then Comes_From_Source (Original_Node (N))
3810 -- Only call test if needed
3812 and then Restriction_Check_Required (SPARK_05)
3813 and then not Is_SPARK_05_Initialization_Expr (Original_Node (E))
3815 Check_SPARK_05_Restriction
3816 ("initialization expression is not appropriate", E);
3819 -- A formal parameter of a specific tagged type whose related
3820 -- subprogram is subject to pragma Extensions_Visible with value
3821 -- "False" cannot be implicitly converted to a class-wide type by
3822 -- means of an initialization expression (SPARK RM 6.1.7(3)).
3824 if Is_Class_Wide_Type (T) and then Is_EVF_Expression (E) then
3826 ("formal parameter with Extensions_Visible False cannot be "
3827 & "implicitly converted to class-wide type", E);
3831 -- If the No_Streams restriction is set, check that the type of the
3832 -- object is not, and does not contain, any subtype derived from
3833 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
3834 -- Has_Stream just for efficiency reasons. There is no point in
3835 -- spending time on a Has_Stream check if the restriction is not set.
3837 if Restriction_Check_Required (No_Streams) then
3838 if Has_Stream (T) then
3839 Check_Restriction (No_Streams, N);
3843 -- Deal with predicate check before we start to do major rewriting. It
3844 -- is OK to initialize and then check the initialized value, since the
3845 -- object goes out of scope if we get a predicate failure. Note that we
3846 -- do this in the analyzer and not the expander because the analyzer
3847 -- does some substantial rewriting in some cases.
3849 -- We need a predicate check if the type has predicates, and if either
3850 -- there is an initializing expression, or for default initialization
3851 -- when we have at least one case of an explicit default initial value
3852 -- and then this is not an internal declaration whose initialization
3853 -- comes later (as for an aggregate expansion).
3855 if not Suppress_Assignment_Checks (N)
3856 and then Present (Predicate_Function (T))
3857 and then not No_Initialization (N)
3861 Is_Partially_Initialized_Type (T, Include_Implicit => False))
3863 -- If the type has a static predicate and the expression is known at
3864 -- compile time, see if the expression satisfies the predicate.
3867 Check_Expression_Against_Static_Predicate (E, T);
3871 Make_Predicate_Check (T, New_Occurrence_Of (Id, Loc)));
3874 -- Case of unconstrained type
3876 if not Is_Definite_Subtype (T) then
3878 -- In SPARK, a declaration of unconstrained type is allowed
3879 -- only for constants of type string.
3881 if Is_String_Type (T) and then not Constant_Present (N) then
3882 Check_SPARK_05_Restriction
3883 ("declaration of object of unconstrained type not allowed", N);
3886 -- Nothing to do in deferred constant case
3888 if Constant_Present (N) and then No (E) then
3891 -- Case of no initialization present
3894 if No_Initialization (N) then
3897 elsif Is_Class_Wide_Type (T) then
3899 ("initialization required in class-wide declaration ", N);
3903 ("unconstrained subtype not allowed (need initialization)",
3904 Object_Definition (N));
3906 if Is_Record_Type (T) and then Has_Discriminants (T) then
3908 ("\provide initial value or explicit discriminant values",
3909 Object_Definition (N));
3912 ("\or give default discriminant values for type&",
3913 Object_Definition (N), T);
3915 elsif Is_Array_Type (T) then
3917 ("\provide initial value or explicit array bounds",
3918 Object_Definition (N));
3922 -- Case of initialization present but in error. Set initial
3923 -- expression as absent (but do not make above complaints)
3925 elsif E = Error then
3926 Set_Expression (N, Empty);
3929 -- Case of initialization present
3932 -- Check restrictions in Ada 83
3934 if not Constant_Present (N) then
3936 -- Unconstrained variables not allowed in Ada 83 mode
3938 if Ada_Version = Ada_83
3939 and then Comes_From_Source (Object_Definition (N))
3942 ("(Ada 83) unconstrained variable not allowed",
3943 Object_Definition (N));
3947 -- Now we constrain the variable from the initializing expression
3949 -- If the expression is an aggregate, it has been expanded into
3950 -- individual assignments. Retrieve the actual type from the
3951 -- expanded construct.
3953 if Is_Array_Type (T)
3954 and then No_Initialization (N)
3955 and then Nkind (Original_Node (E)) = N_Aggregate
3959 -- In case of class-wide interface object declarations we delay
3960 -- the generation of the equivalent record type declarations until
3961 -- its expansion because there are cases in they are not required.
3963 elsif Is_Interface (T) then
3966 -- In GNATprove mode, Expand_Subtype_From_Expr does nothing. Thus,
3967 -- we should prevent the generation of another Itype with the
3968 -- same name as the one already generated, or we end up with
3969 -- two identical types in GNATprove.
3971 elsif GNATprove_Mode then
3974 -- If the type is an unchecked union, no subtype can be built from
3975 -- the expression. Rewrite declaration as a renaming, which the
3976 -- back-end can handle properly. This is a rather unusual case,
3977 -- because most unchecked_union declarations have default values
3978 -- for discriminants and are thus not indefinite.
3980 elsif Is_Unchecked_Union (T) then
3981 if Constant_Present (N) or else Nkind (E) = N_Function_Call then
3982 Set_Ekind (Id, E_Constant);
3984 Set_Ekind (Id, E_Variable);
3987 -- An object declared within a Ghost region is automatically
3988 -- Ghost (SPARK RM 6.9(2)).
3990 if Ghost_Mode > None then
3991 Set_Is_Ghost_Entity (Id);
3993 -- The Ghost policy in effect at the point of declaration
3994 -- and at the point of completion must match
3995 -- (SPARK RM 6.9(14)).
3997 if Present (Prev_Entity)
3998 and then Is_Ghost_Entity (Prev_Entity)
4000 Check_Ghost_Completion (Prev_Entity, Id);
4005 Make_Object_Renaming_Declaration (Loc,
4006 Defining_Identifier => Id,
4007 Subtype_Mark => New_Occurrence_Of (T, Loc),
4010 Set_Renamed_Object (Id, E);
4011 Freeze_Before (N, T);
4014 Ghost_Mode := Save_Ghost_Mode;
4018 Expand_Subtype_From_Expr (N, T, Object_Definition (N), E);
4019 Act_T := Find_Type_Of_Object (Object_Definition (N), N);
4022 Set_Is_Constr_Subt_For_U_Nominal (Act_T);
4024 if Aliased_Present (N) then
4025 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
4028 Freeze_Before (N, Act_T);
4029 Freeze_Before (N, T);
4032 elsif Is_Array_Type (T)
4033 and then No_Initialization (N)
4034 and then Nkind (Original_Node (E)) = N_Aggregate
4036 if not Is_Entity_Name (Object_Definition (N)) then
4038 Check_Compile_Time_Size (Act_T);
4040 if Aliased_Present (N) then
4041 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
4045 -- When the given object definition and the aggregate are specified
4046 -- independently, and their lengths might differ do a length check.
4047 -- This cannot happen if the aggregate is of the form (others =>...)
4049 if not Is_Constrained (T) then
4052 elsif Nkind (E) = N_Raise_Constraint_Error then
4054 -- Aggregate is statically illegal. Place back in declaration
4056 Set_Expression (N, E);
4057 Set_No_Initialization (N, False);
4059 elsif T = Etype (E) then
4062 elsif Nkind (E) = N_Aggregate
4063 and then Present (Component_Associations (E))
4064 and then Present (Choices (First (Component_Associations (E))))
4065 and then Nkind (First
4066 (Choices (First (Component_Associations (E))))) = N_Others_Choice
4071 Apply_Length_Check (E, T);
4074 -- If the type is limited unconstrained with defaulted discriminants and
4075 -- there is no expression, then the object is constrained by the
4076 -- defaults, so it is worthwhile building the corresponding subtype.
4078 elsif (Is_Limited_Record (T) or else Is_Concurrent_Type (T))
4079 and then not Is_Constrained (T)
4080 and then Has_Discriminants (T)
4083 Act_T := Build_Default_Subtype (T, N);
4085 -- Ada 2005: A limited object may be initialized by means of an
4086 -- aggregate. If the type has default discriminants it has an
4087 -- unconstrained nominal type, Its actual subtype will be obtained
4088 -- from the aggregate, and not from the default discriminants.
4093 Rewrite (Object_Definition (N), New_Occurrence_Of (Act_T, Loc));
4095 elsif Nkind (E) = N_Function_Call
4096 and then Constant_Present (N)
4097 and then Has_Unconstrained_Elements (Etype (E))
4099 -- The back-end has problems with constants of a discriminated type
4100 -- with defaults, if the initial value is a function call. We
4101 -- generate an intermediate temporary that will receive a reference
4102 -- to the result of the call. The initialization expression then
4103 -- becomes a dereference of that temporary.
4105 Remove_Side_Effects (E);
4107 -- If this is a constant declaration of an unconstrained type and
4108 -- the initialization is an aggregate, we can use the subtype of the
4109 -- aggregate for the declared entity because it is immutable.
4111 elsif not Is_Constrained (T)
4112 and then Has_Discriminants (T)
4113 and then Constant_Present (N)
4114 and then not Has_Unchecked_Union (T)
4115 and then Nkind (E) = N_Aggregate
4120 -- Check No_Wide_Characters restriction
4122 Check_Wide_Character_Restriction (T, Object_Definition (N));
4124 -- Indicate this is not set in source. Certainly true for constants, and
4125 -- true for variables so far (will be reset for a variable if and when
4126 -- we encounter a modification in the source).
4128 Set_Never_Set_In_Source (Id);
4130 -- Now establish the proper kind and type of the object
4132 if Constant_Present (N) then
4133 Set_Ekind (Id, E_Constant);
4134 Set_Is_True_Constant (Id);
4137 Set_Ekind (Id, E_Variable);
4139 -- A variable is set as shared passive if it appears in a shared
4140 -- passive package, and is at the outer level. This is not done for
4141 -- entities generated during expansion, because those are always
4142 -- manipulated locally.
4144 if Is_Shared_Passive (Current_Scope)
4145 and then Is_Library_Level_Entity (Id)
4146 and then Comes_From_Source (Id)
4148 Set_Is_Shared_Passive (Id);
4149 Check_Shared_Var (Id, T, N);
4152 -- Set Has_Initial_Value if initializing expression present. Note
4153 -- that if there is no initializing expression, we leave the state
4154 -- of this flag unchanged (usually it will be False, but notably in
4155 -- the case of exception choice variables, it will already be true).
4158 Set_Has_Initial_Value (Id);
4162 -- Initialize alignment and size and capture alignment setting
4164 Init_Alignment (Id);
4166 Set_Optimize_Alignment_Flags (Id);
4168 -- An object declared within a Ghost region is automatically Ghost
4169 -- (SPARK RM 6.9(2)).
4171 if Ghost_Mode > None
4172 or else (Present (Prev_Entity) and then Is_Ghost_Entity (Prev_Entity))
4174 Set_Is_Ghost_Entity (Id);
4176 -- The Ghost policy in effect at the point of declaration and at the
4177 -- point of completion must match (SPARK RM 6.9(14)).
4179 if Present (Prev_Entity) and then Is_Ghost_Entity (Prev_Entity) then
4180 Check_Ghost_Completion (Prev_Entity, Id);
4184 -- Deal with aliased case
4186 if Aliased_Present (N) then
4187 Set_Is_Aliased (Id);
4189 -- If the object is aliased and the type is unconstrained with
4190 -- defaulted discriminants and there is no expression, then the
4191 -- object is constrained by the defaults, so it is worthwhile
4192 -- building the corresponding subtype.
4194 -- Ada 2005 (AI-363): If the aliased object is discriminated and
4195 -- unconstrained, then only establish an actual subtype if the
4196 -- nominal subtype is indefinite. In definite cases the object is
4197 -- unconstrained in Ada 2005.
4200 and then Is_Record_Type (T)
4201 and then not Is_Constrained (T)
4202 and then Has_Discriminants (T)
4203 and then (Ada_Version < Ada_2005
4204 or else not Is_Definite_Subtype (T))
4206 Set_Actual_Subtype (Id, Build_Default_Subtype (T, N));
4210 -- Now we can set the type of the object
4212 Set_Etype (Id, Act_T);
4214 -- Non-constant object is marked to be treated as volatile if type is
4215 -- volatile and we clear the Current_Value setting that may have been
4216 -- set above. Doing so for constants isn't required and might interfere
4217 -- with possible uses of the object as a static expression in contexts
4218 -- incompatible with volatility (e.g. as a case-statement alternative).
4220 if Ekind (Id) /= E_Constant and then Treat_As_Volatile (Etype (Id)) then
4221 Set_Treat_As_Volatile (Id);
4222 Set_Current_Value (Id, Empty);
4225 -- Deal with controlled types
4227 if Has_Controlled_Component (Etype (Id))
4228 or else Is_Controlled (Etype (Id))
4230 if not Is_Library_Level_Entity (Id) then
4231 Check_Restriction (No_Nested_Finalization, N);
4233 Validate_Controlled_Object (Id);
4237 if Has_Task (Etype (Id)) then
4238 Check_Restriction (No_Tasking, N);
4240 -- Deal with counting max tasks
4242 -- Nothing to do if inside a generic
4244 if Inside_A_Generic then
4247 -- If library level entity, then count tasks
4249 elsif Is_Library_Level_Entity (Id) then
4250 Check_Restriction (Max_Tasks, N, Count_Tasks (Etype (Id)));
4252 -- If not library level entity, then indicate we don't know max
4253 -- tasks and also check task hierarchy restriction and blocking
4254 -- operation (since starting a task is definitely blocking).
4257 Check_Restriction (Max_Tasks, N);
4258 Check_Restriction (No_Task_Hierarchy, N);
4259 Check_Potentially_Blocking_Operation (N);
4262 -- A rather specialized test. If we see two tasks being declared
4263 -- of the same type in the same object declaration, and the task
4264 -- has an entry with an address clause, we know that program error
4265 -- will be raised at run time since we can't have two tasks with
4266 -- entries at the same address.
4268 if Is_Task_Type (Etype (Id)) and then More_Ids (N) then
4273 E := First_Entity (Etype (Id));
4274 while Present (E) loop
4275 if Ekind (E) = E_Entry
4276 and then Present (Get_Attribute_Definition_Clause
4277 (E, Attribute_Address))
4279 Error_Msg_Warn := SPARK_Mode /= On;
4281 ("more than one task with same entry address<<", N);
4282 Error_Msg_N ("\Program_Error [<<", N);
4284 Make_Raise_Program_Error (Loc,
4285 Reason => PE_Duplicated_Entry_Address));
4295 -- Some simple constant-propagation: if the expression is a constant
4296 -- string initialized with a literal, share the literal. This avoids
4300 and then Is_Entity_Name (E)
4301 and then Ekind (Entity (E)) = E_Constant
4302 and then Base_Type (Etype (E)) = Standard_String
4305 Val : constant Node_Id := Constant_Value (Entity (E));
4307 if Present (Val) and then Nkind (Val) = N_String_Literal then
4308 Rewrite (E, New_Copy (Val));
4313 -- Another optimization: if the nominal subtype is unconstrained and
4314 -- the expression is a function call that returns an unconstrained
4315 -- type, rewrite the declaration as a renaming of the result of the
4316 -- call. The exceptions below are cases where the copy is expected,
4317 -- either by the back end (Aliased case) or by the semantics, as for
4318 -- initializing controlled types or copying tags for classwide types.
4321 and then Nkind (E) = N_Explicit_Dereference
4322 and then Nkind (Original_Node (E)) = N_Function_Call
4323 and then not Is_Library_Level_Entity (Id)
4324 and then not Is_Constrained (Underlying_Type (T))
4325 and then not Is_Aliased (Id)
4326 and then not Is_Class_Wide_Type (T)
4327 and then not Is_Controlled_Active (T)
4328 and then not Has_Controlled_Component (Base_Type (T))
4329 and then Expander_Active
4332 Make_Object_Renaming_Declaration (Loc,
4333 Defining_Identifier => Id,
4334 Access_Definition => Empty,
4335 Subtype_Mark => New_Occurrence_Of
4336 (Base_Type (Etype (Id)), Loc),
4339 Set_Renamed_Object (Id, E);
4341 -- Force generation of debugging information for the constant and for
4342 -- the renamed function call.
4344 Set_Debug_Info_Needed (Id);
4345 Set_Debug_Info_Needed (Entity (Prefix (E)));
4348 if Present (Prev_Entity)
4349 and then Is_Frozen (Prev_Entity)
4350 and then not Error_Posted (Id)
4352 Error_Msg_N ("full constant declaration appears too late", N);
4355 Check_Eliminated (Id);
4357 -- Deal with setting In_Private_Part flag if in private part
4359 if Ekind (Scope (Id)) = E_Package
4360 and then In_Private_Part (Scope (Id))
4362 Set_In_Private_Part (Id);
4365 -- Check for violation of No_Local_Timing_Events
4367 if Restriction_Check_Required (No_Local_Timing_Events)
4368 and then not Is_Library_Level_Entity (Id)
4369 and then Is_RTE (Etype (Id), RE_Timing_Event)
4371 Check_Restriction (No_Local_Timing_Events, N);
4375 -- Initialize the refined state of a variable here because this is a
4376 -- common destination for legal and illegal object declarations.
4378 if Ekind (Id) = E_Variable then
4379 Set_Encapsulating_State (Id, Empty);
4382 if Has_Aspects (N) then
4383 Analyze_Aspect_Specifications (N, Id);
4386 Analyze_Dimension (N);
4388 -- Verify whether the object declaration introduces an illegal hidden
4389 -- state within a package subject to a null abstract state.
4391 if Ekind (Id) = E_Variable then
4392 Check_No_Hidden_State (Id);
4395 Ghost_Mode := Save_Ghost_Mode;
4396 end Analyze_Object_Declaration;
4398 ---------------------------
4399 -- Analyze_Others_Choice --
4400 ---------------------------
4402 -- Nothing to do for the others choice node itself, the semantic analysis
4403 -- of the others choice will occur as part of the processing of the parent
4405 procedure Analyze_Others_Choice (N : Node_Id) is
4406 pragma Warnings (Off, N);
4409 end Analyze_Others_Choice;
4411 -------------------------------------------
4412 -- Analyze_Private_Extension_Declaration --
4413 -------------------------------------------
4415 procedure Analyze_Private_Extension_Declaration (N : Node_Id) is
4416 Indic : constant Node_Id := Subtype_Indication (N);
4417 T : constant Entity_Id := Defining_Identifier (N);
4418 Parent_Base : Entity_Id;
4419 Parent_Type : Entity_Id;
4422 -- Ada 2005 (AI-251): Decorate all names in list of ancestor interfaces
4424 if Is_Non_Empty_List (Interface_List (N)) then
4430 Intf := First (Interface_List (N));
4431 while Present (Intf) loop
4432 T := Find_Type_Of_Subtype_Indic (Intf);
4434 Diagnose_Interface (Intf, T);
4440 Generate_Definition (T);
4442 -- For other than Ada 2012, just enter the name in the current scope
4444 if Ada_Version < Ada_2012 then
4447 -- Ada 2012 (AI05-0162): Enter the name in the current scope handling
4448 -- case of private type that completes an incomplete type.
4455 Prev := Find_Type_Name (N);
4457 pragma Assert (Prev = T
4458 or else (Ekind (Prev) = E_Incomplete_Type
4459 and then Present (Full_View (Prev))
4460 and then Full_View (Prev) = T));
4464 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
4465 Parent_Base := Base_Type (Parent_Type);
4467 if Parent_Type = Any_Type or else Etype (Parent_Type) = Any_Type then
4468 Set_Ekind (T, Ekind (Parent_Type));
4469 Set_Etype (T, Any_Type);
4472 elsif not Is_Tagged_Type (Parent_Type) then
4474 ("parent of type extension must be a tagged type ", Indic);
4477 elsif Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
4478 Error_Msg_N ("premature derivation of incomplete type", Indic);
4481 elsif Is_Concurrent_Type (Parent_Type) then
4483 ("parent type of a private extension cannot be "
4484 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
4486 Set_Etype (T, Any_Type);
4487 Set_Ekind (T, E_Limited_Private_Type);
4488 Set_Private_Dependents (T, New_Elmt_List);
4489 Set_Error_Posted (T);
4493 -- Perhaps the parent type should be changed to the class-wide type's
4494 -- specific type in this case to prevent cascading errors ???
4496 if Is_Class_Wide_Type (Parent_Type) then
4498 ("parent of type extension must not be a class-wide type", Indic);
4502 if (not Is_Package_Or_Generic_Package (Current_Scope)
4503 and then Nkind (Parent (N)) /= N_Generic_Subprogram_Declaration)
4504 or else In_Private_Part (Current_Scope)
4507 Error_Msg_N ("invalid context for private extension", N);
4510 -- Set common attributes
4512 Set_Is_Pure (T, Is_Pure (Current_Scope));
4513 Set_Scope (T, Current_Scope);
4514 Set_Ekind (T, E_Record_Type_With_Private);
4515 Init_Size_Align (T);
4516 Set_Default_SSO (T);
4518 Set_Etype (T, Parent_Base);
4519 Set_Has_Task (T, Has_Task (Parent_Base));
4520 Set_Has_Protected (T, Has_Task (Parent_Base));
4522 Set_Convention (T, Convention (Parent_Type));
4523 Set_First_Rep_Item (T, First_Rep_Item (Parent_Type));
4524 Set_Is_First_Subtype (T);
4525 Make_Class_Wide_Type (T);
4527 if Unknown_Discriminants_Present (N) then
4528 Set_Discriminant_Constraint (T, No_Elist);
4531 Build_Derived_Record_Type (N, Parent_Type, T);
4533 -- Propagate inherited invariant information. The new type has
4534 -- invariants, if the parent type has inheritable invariants,
4535 -- and these invariants can in turn be inherited.
4537 if Has_Inheritable_Invariants (Parent_Type) then
4538 Set_Has_Inheritable_Invariants (T);
4539 Set_Has_Invariants (T);
4542 -- Ada 2005 (AI-443): Synchronized private extension or a rewritten
4543 -- synchronized formal derived type.
4545 if Ada_Version >= Ada_2005 and then Synchronized_Present (N) then
4546 Set_Is_Limited_Record (T);
4548 -- Formal derived type case
4550 if Is_Generic_Type (T) then
4552 -- The parent must be a tagged limited type or a synchronized
4555 if (not Is_Tagged_Type (Parent_Type)
4556 or else not Is_Limited_Type (Parent_Type))
4558 (not Is_Interface (Parent_Type)
4559 or else not Is_Synchronized_Interface (Parent_Type))
4561 Error_Msg_NE ("parent type of & must be tagged limited " &
4562 "or synchronized", N, T);
4565 -- The progenitors (if any) must be limited or synchronized
4568 if Present (Interfaces (T)) then
4571 Iface_Elmt : Elmt_Id;
4574 Iface_Elmt := First_Elmt (Interfaces (T));
4575 while Present (Iface_Elmt) loop
4576 Iface := Node (Iface_Elmt);
4578 if not Is_Limited_Interface (Iface)
4579 and then not Is_Synchronized_Interface (Iface)
4581 Error_Msg_NE ("progenitor & must be limited " &
4582 "or synchronized", N, Iface);
4585 Next_Elmt (Iface_Elmt);
4590 -- Regular derived extension, the parent must be a limited or
4591 -- synchronized interface.
4594 if not Is_Interface (Parent_Type)
4595 or else (not Is_Limited_Interface (Parent_Type)
4596 and then not Is_Synchronized_Interface (Parent_Type))
4599 ("parent type of & must be limited interface", N, T);
4603 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
4604 -- extension with a synchronized parent must be explicitly declared
4605 -- synchronized, because the full view will be a synchronized type.
4606 -- This must be checked before the check for limited types below,
4607 -- to ensure that types declared limited are not allowed to extend
4608 -- synchronized interfaces.
4610 elsif Is_Interface (Parent_Type)
4611 and then Is_Synchronized_Interface (Parent_Type)
4612 and then not Synchronized_Present (N)
4615 ("private extension of& must be explicitly synchronized",
4618 elsif Limited_Present (N) then
4619 Set_Is_Limited_Record (T);
4621 if not Is_Limited_Type (Parent_Type)
4623 (not Is_Interface (Parent_Type)
4624 or else not Is_Limited_Interface (Parent_Type))
4626 Error_Msg_NE ("parent type& of limited extension must be limited",
4632 if Has_Aspects (N) then
4633 Analyze_Aspect_Specifications (N, T);
4635 end Analyze_Private_Extension_Declaration;
4637 ---------------------------------
4638 -- Analyze_Subtype_Declaration --
4639 ---------------------------------
4641 procedure Analyze_Subtype_Declaration
4643 Skip : Boolean := False)
4645 Id : constant Entity_Id := Defining_Identifier (N);
4646 R_Checks : Check_Result;
4650 Generate_Definition (Id);
4651 Set_Is_Pure (Id, Is_Pure (Current_Scope));
4652 Init_Size_Align (Id);
4654 -- The following guard condition on Enter_Name is to handle cases where
4655 -- the defining identifier has already been entered into the scope but
4656 -- the declaration as a whole needs to be analyzed.
4658 -- This case in particular happens for derived enumeration types. The
4659 -- derived enumeration type is processed as an inserted enumeration type
4660 -- declaration followed by a rewritten subtype declaration. The defining
4661 -- identifier, however, is entered into the name scope very early in the
4662 -- processing of the original type declaration and therefore needs to be
4663 -- avoided here, when the created subtype declaration is analyzed. (See
4664 -- Build_Derived_Types)
4666 -- This also happens when the full view of a private type is derived
4667 -- type with constraints. In this case the entity has been introduced
4668 -- in the private declaration.
4670 -- Finally this happens in some complex cases when validity checks are
4671 -- enabled, where the same subtype declaration may be analyzed twice.
4672 -- This can happen if the subtype is created by the pre-analysis of
4673 -- an attribute tht gives the range of a loop statement, and the loop
4674 -- itself appears within an if_statement that will be rewritten during
4678 or else (Present (Etype (Id))
4679 and then (Is_Private_Type (Etype (Id))
4680 or else Is_Task_Type (Etype (Id))
4681 or else Is_Rewrite_Substitution (N)))
4685 elsif Current_Entity (Id) = Id then
4692 T := Process_Subtype (Subtype_Indication (N), N, Id, 'P');
4694 -- Class-wide equivalent types of records with unknown discriminants
4695 -- involve the generation of an itype which serves as the private view
4696 -- of a constrained record subtype. In such cases the base type of the
4697 -- current subtype we are processing is the private itype. Use the full
4698 -- of the private itype when decorating various attributes.
4701 and then Is_Private_Type (T)
4702 and then Present (Full_View (T))
4707 -- Inherit common attributes
4709 Set_Is_Volatile (Id, Is_Volatile (T));
4710 Set_Treat_As_Volatile (Id, Treat_As_Volatile (T));
4711 Set_Is_Generic_Type (Id, Is_Generic_Type (Base_Type (T)));
4712 Set_Convention (Id, Convention (T));
4714 -- If ancestor has predicates then so does the subtype, and in addition
4715 -- we must delay the freeze to properly arrange predicate inheritance.
4717 -- The Ancestor_Type test is really unpleasant, there seem to be cases
4718 -- in which T = ID, so the above tests and assignments do nothing???
4720 if Has_Predicates (T)
4721 or else (Present (Ancestor_Subtype (T))
4722 and then Has_Predicates (Ancestor_Subtype (T)))
4724 Set_Has_Predicates (Id);
4725 Set_Has_Delayed_Freeze (Id);
4728 -- Subtype of Boolean cannot have a constraint in SPARK
4730 if Is_Boolean_Type (T)
4731 and then Nkind (Subtype_Indication (N)) = N_Subtype_Indication
4733 Check_SPARK_05_Restriction
4734 ("subtype of Boolean cannot have constraint", N);
4737 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4739 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
4745 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint then
4746 One_Cstr := First (Constraints (Cstr));
4747 while Present (One_Cstr) loop
4749 -- Index or discriminant constraint in SPARK must be a
4753 Nkind_In (One_Cstr, N_Identifier, N_Expanded_Name)
4755 Check_SPARK_05_Restriction
4756 ("subtype mark required", One_Cstr);
4758 -- String subtype must have a lower bound of 1 in SPARK.
4759 -- Note that we do not need to test for the non-static case
4760 -- here, since that was already taken care of in
4761 -- Process_Range_Expr_In_Decl.
4763 elsif Base_Type (T) = Standard_String then
4764 Get_Index_Bounds (One_Cstr, Low, High);
4766 if Is_OK_Static_Expression (Low)
4767 and then Expr_Value (Low) /= 1
4769 Check_SPARK_05_Restriction
4770 ("String subtype must have lower bound of 1", N);
4780 -- In the case where there is no constraint given in the subtype
4781 -- indication, Process_Subtype just returns the Subtype_Mark, so its
4782 -- semantic attributes must be established here.
4784 if Nkind (Subtype_Indication (N)) /= N_Subtype_Indication then
4785 Set_Etype (Id, Base_Type (T));
4787 -- Subtype of unconstrained array without constraint is not allowed
4790 if Is_Array_Type (T) and then not Is_Constrained (T) then
4791 Check_SPARK_05_Restriction
4792 ("subtype of unconstrained array must have constraint", N);
4797 Set_Ekind (Id, E_Array_Subtype);
4798 Copy_Array_Subtype_Attributes (Id, T);
4800 when Decimal_Fixed_Point_Kind =>
4801 Set_Ekind (Id, E_Decimal_Fixed_Point_Subtype);
4802 Set_Digits_Value (Id, Digits_Value (T));
4803 Set_Delta_Value (Id, Delta_Value (T));
4804 Set_Scale_Value (Id, Scale_Value (T));
4805 Set_Small_Value (Id, Small_Value (T));
4806 Set_Scalar_Range (Id, Scalar_Range (T));
4807 Set_Machine_Radix_10 (Id, Machine_Radix_10 (T));
4808 Set_Is_Constrained (Id, Is_Constrained (T));
4809 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4810 Set_RM_Size (Id, RM_Size (T));
4812 when Enumeration_Kind =>
4813 Set_Ekind (Id, E_Enumeration_Subtype);
4814 Set_First_Literal (Id, First_Literal (Base_Type (T)));
4815 Set_Scalar_Range (Id, Scalar_Range (T));
4816 Set_Is_Character_Type (Id, Is_Character_Type (T));
4817 Set_Is_Constrained (Id, Is_Constrained (T));
4818 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4819 Set_RM_Size (Id, RM_Size (T));
4820 Inherit_Predicate_Flags (Id, T);
4822 when Ordinary_Fixed_Point_Kind =>
4823 Set_Ekind (Id, E_Ordinary_Fixed_Point_Subtype);
4824 Set_Scalar_Range (Id, Scalar_Range (T));
4825 Set_Small_Value (Id, Small_Value (T));
4826 Set_Delta_Value (Id, Delta_Value (T));
4827 Set_Is_Constrained (Id, Is_Constrained (T));
4828 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4829 Set_RM_Size (Id, RM_Size (T));
4832 Set_Ekind (Id, E_Floating_Point_Subtype);
4833 Set_Scalar_Range (Id, Scalar_Range (T));
4834 Set_Digits_Value (Id, Digits_Value (T));
4835 Set_Is_Constrained (Id, Is_Constrained (T));
4837 -- If the floating point type has dimensions, these will be
4838 -- inherited subsequently when Analyze_Dimensions is called.
4840 when Signed_Integer_Kind =>
4841 Set_Ekind (Id, E_Signed_Integer_Subtype);
4842 Set_Scalar_Range (Id, Scalar_Range (T));
4843 Set_Is_Constrained (Id, Is_Constrained (T));
4844 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4845 Set_RM_Size (Id, RM_Size (T));
4846 Inherit_Predicate_Flags (Id, T);
4848 when Modular_Integer_Kind =>
4849 Set_Ekind (Id, E_Modular_Integer_Subtype);
4850 Set_Scalar_Range (Id, Scalar_Range (T));
4851 Set_Is_Constrained (Id, Is_Constrained (T));
4852 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4853 Set_RM_Size (Id, RM_Size (T));
4854 Inherit_Predicate_Flags (Id, T);
4856 when Class_Wide_Kind =>
4857 Set_Ekind (Id, E_Class_Wide_Subtype);
4858 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4859 Set_Cloned_Subtype (Id, T);
4860 Set_Is_Tagged_Type (Id, True);
4861 Set_Has_Unknown_Discriminants
4863 Set_No_Tagged_Streams_Pragma
4864 (Id, No_Tagged_Streams_Pragma (T));
4866 if Ekind (T) = E_Class_Wide_Subtype then
4867 Set_Equivalent_Type (Id, Equivalent_Type (T));
4870 when E_Record_Type | E_Record_Subtype =>
4871 Set_Ekind (Id, E_Record_Subtype);
4873 if Ekind (T) = E_Record_Subtype
4874 and then Present (Cloned_Subtype (T))
4876 Set_Cloned_Subtype (Id, Cloned_Subtype (T));
4878 Set_Cloned_Subtype (Id, T);
4881 Set_First_Entity (Id, First_Entity (T));
4882 Set_Last_Entity (Id, Last_Entity (T));
4883 Set_Has_Discriminants (Id, Has_Discriminants (T));
4884 Set_Is_Constrained (Id, Is_Constrained (T));
4885 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4886 Set_Has_Implicit_Dereference
4887 (Id, Has_Implicit_Dereference (T));
4888 Set_Has_Unknown_Discriminants
4889 (Id, Has_Unknown_Discriminants (T));
4891 if Has_Discriminants (T) then
4892 Set_Discriminant_Constraint
4893 (Id, Discriminant_Constraint (T));
4894 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4896 elsif Has_Unknown_Discriminants (Id) then
4897 Set_Discriminant_Constraint (Id, No_Elist);
4900 if Is_Tagged_Type (T) then
4901 Set_Is_Tagged_Type (Id, True);
4902 Set_No_Tagged_Streams_Pragma
4903 (Id, No_Tagged_Streams_Pragma (T));
4904 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4905 Set_Direct_Primitive_Operations
4906 (Id, Direct_Primitive_Operations (T));
4907 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4909 if Is_Interface (T) then
4910 Set_Is_Interface (Id);
4911 Set_Is_Limited_Interface (Id, Is_Limited_Interface (T));
4915 when Private_Kind =>
4916 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4917 Set_Has_Discriminants (Id, Has_Discriminants (T));
4918 Set_Is_Constrained (Id, Is_Constrained (T));
4919 Set_First_Entity (Id, First_Entity (T));
4920 Set_Last_Entity (Id, Last_Entity (T));
4921 Set_Private_Dependents (Id, New_Elmt_List);
4922 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4923 Set_Has_Implicit_Dereference
4924 (Id, Has_Implicit_Dereference (T));
4925 Set_Has_Unknown_Discriminants
4926 (Id, Has_Unknown_Discriminants (T));
4927 Set_Known_To_Have_Preelab_Init
4928 (Id, Known_To_Have_Preelab_Init (T));
4930 if Is_Tagged_Type (T) then
4931 Set_Is_Tagged_Type (Id);
4932 Set_No_Tagged_Streams_Pragma (Id,
4933 No_Tagged_Streams_Pragma (T));
4934 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4935 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4936 Set_Direct_Primitive_Operations (Id,
4937 Direct_Primitive_Operations (T));
4940 -- In general the attributes of the subtype of a private type
4941 -- are the attributes of the partial view of parent. However,
4942 -- the full view may be a discriminated type, and the subtype
4943 -- must share the discriminant constraint to generate correct
4944 -- calls to initialization procedures.
4946 if Has_Discriminants (T) then
4947 Set_Discriminant_Constraint
4948 (Id, Discriminant_Constraint (T));
4949 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4951 elsif Present (Full_View (T))
4952 and then Has_Discriminants (Full_View (T))
4954 Set_Discriminant_Constraint
4955 (Id, Discriminant_Constraint (Full_View (T)));
4956 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4958 -- This would seem semantically correct, but apparently
4959 -- generates spurious errors about missing components ???
4961 -- Set_Has_Discriminants (Id);
4964 Prepare_Private_Subtype_Completion (Id, N);
4966 -- If this is the subtype of a constrained private type with
4967 -- discriminants that has got a full view and we also have
4968 -- built a completion just above, show that the completion
4969 -- is a clone of the full view to the back-end.
4971 if Has_Discriminants (T)
4972 and then not Has_Unknown_Discriminants (T)
4973 and then not Is_Empty_Elmt_List (Discriminant_Constraint (T))
4974 and then Present (Full_View (T))
4975 and then Present (Full_View (Id))
4977 Set_Cloned_Subtype (Full_View (Id), Full_View (T));
4981 Set_Ekind (Id, E_Access_Subtype);
4982 Set_Is_Constrained (Id, Is_Constrained (T));
4983 Set_Is_Access_Constant
4984 (Id, Is_Access_Constant (T));
4985 Set_Directly_Designated_Type
4986 (Id, Designated_Type (T));
4987 Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T));
4989 -- A Pure library_item must not contain the declaration of a
4990 -- named access type, except within a subprogram, generic
4991 -- subprogram, task unit, or protected unit, or if it has
4992 -- a specified Storage_Size of zero (RM05-10.2.1(15.4-15.5)).
4994 if Comes_From_Source (Id)
4995 and then In_Pure_Unit
4996 and then not In_Subprogram_Task_Protected_Unit
4997 and then not No_Pool_Assigned (Id)
5000 ("named access types not allowed in pure unit", N);
5003 when Concurrent_Kind =>
5004 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
5005 Set_Corresponding_Record_Type (Id,
5006 Corresponding_Record_Type (T));
5007 Set_First_Entity (Id, First_Entity (T));
5008 Set_First_Private_Entity (Id, First_Private_Entity (T));
5009 Set_Has_Discriminants (Id, Has_Discriminants (T));
5010 Set_Is_Constrained (Id, Is_Constrained (T));
5011 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
5012 Set_Last_Entity (Id, Last_Entity (T));
5014 if Is_Tagged_Type (T) then
5015 Set_No_Tagged_Streams_Pragma
5016 (Id, No_Tagged_Streams_Pragma (T));
5019 if Has_Discriminants (T) then
5020 Set_Discriminant_Constraint
5021 (Id, Discriminant_Constraint (T));
5022 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5025 when Incomplete_Kind =>
5026 if Ada_Version >= Ada_2005 then
5028 -- In Ada 2005 an incomplete type can be explicitly tagged:
5029 -- propagate indication. Note that we also have to include
5030 -- subtypes for Ada 2012 extended use of incomplete types.
5032 Set_Ekind (Id, E_Incomplete_Subtype);
5033 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
5034 Set_Private_Dependents (Id, New_Elmt_List);
5036 if Is_Tagged_Type (Id) then
5037 Set_No_Tagged_Streams_Pragma
5038 (Id, No_Tagged_Streams_Pragma (T));
5039 Set_Direct_Primitive_Operations (Id, New_Elmt_List);
5042 -- Ada 2005 (AI-412): Decorate an incomplete subtype of an
5043 -- incomplete type visible through a limited with clause.
5045 if From_Limited_With (T)
5046 and then Present (Non_Limited_View (T))
5048 Set_From_Limited_With (Id);
5049 Set_Non_Limited_View (Id, Non_Limited_View (T));
5051 -- Ada 2005 (AI-412): Add the regular incomplete subtype
5052 -- to the private dependents of the original incomplete
5053 -- type for future transformation.
5056 Append_Elmt (Id, Private_Dependents (T));
5059 -- If the subtype name denotes an incomplete type an error
5060 -- was already reported by Process_Subtype.
5063 Set_Etype (Id, Any_Type);
5067 raise Program_Error;
5071 if Etype (Id) = Any_Type then
5075 -- Some common processing on all types
5077 Set_Size_Info (Id, T);
5078 Set_First_Rep_Item (Id, First_Rep_Item (T));
5080 -- If the parent type is a generic actual, so is the subtype. This may
5081 -- happen in a nested instance. Why Comes_From_Source test???
5083 if not Comes_From_Source (N) then
5084 Set_Is_Generic_Actual_Type (Id, Is_Generic_Actual_Type (T));
5089 Set_Is_Immediately_Visible (Id, True);
5090 Set_Depends_On_Private (Id, Has_Private_Component (T));
5091 Set_Is_Descendent_Of_Address (Id, Is_Descendent_Of_Address (T));
5093 if Is_Interface (T) then
5094 Set_Is_Interface (Id);
5097 if Present (Generic_Parent_Type (N))
5099 (Nkind (Parent (Generic_Parent_Type (N))) /=
5100 N_Formal_Type_Declaration
5101 or else Nkind (Formal_Type_Definition
5102 (Parent (Generic_Parent_Type (N)))) /=
5103 N_Formal_Private_Type_Definition)
5105 if Is_Tagged_Type (Id) then
5107 -- If this is a generic actual subtype for a synchronized type,
5108 -- the primitive operations are those of the corresponding record
5109 -- for which there is a separate subtype declaration.
5111 if Is_Concurrent_Type (Id) then
5113 elsif Is_Class_Wide_Type (Id) then
5114 Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T));
5116 Derive_Subprograms (Generic_Parent_Type (N), Id, T);
5119 elsif Scope (Etype (Id)) /= Standard_Standard then
5120 Derive_Subprograms (Generic_Parent_Type (N), Id);
5124 if Is_Private_Type (T) and then Present (Full_View (T)) then
5125 Conditional_Delay (Id, Full_View (T));
5127 -- The subtypes of components or subcomponents of protected types
5128 -- do not need freeze nodes, which would otherwise appear in the
5129 -- wrong scope (before the freeze node for the protected type). The
5130 -- proper subtypes are those of the subcomponents of the corresponding
5133 elsif Ekind (Scope (Id)) /= E_Protected_Type
5134 and then Present (Scope (Scope (Id))) -- error defense
5135 and then Ekind (Scope (Scope (Id))) /= E_Protected_Type
5137 Conditional_Delay (Id, T);
5140 -- Check that Constraint_Error is raised for a scalar subtype indication
5141 -- when the lower or upper bound of a non-null range lies outside the
5142 -- range of the type mark.
5144 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5145 if Is_Scalar_Type (Etype (Id))
5146 and then Scalar_Range (Id) /=
5147 Scalar_Range (Etype (Subtype_Mark
5148 (Subtype_Indication (N))))
5152 Etype (Subtype_Mark (Subtype_Indication (N))));
5154 -- In the array case, check compatibility for each index
5156 elsif Is_Array_Type (Etype (Id)) and then Present (First_Index (Id))
5158 -- This really should be a subprogram that finds the indications
5162 Subt_Index : Node_Id := First_Index (Id);
5163 Target_Index : Node_Id :=
5165 (Subtype_Mark (Subtype_Indication (N))));
5166 Has_Dyn_Chk : Boolean := Has_Dynamic_Range_Check (N);
5169 while Present (Subt_Index) loop
5170 if ((Nkind (Subt_Index) = N_Identifier
5171 and then Ekind (Entity (Subt_Index)) in Scalar_Kind)
5172 or else Nkind (Subt_Index) = N_Subtype_Indication)
5174 Nkind (Scalar_Range (Etype (Subt_Index))) = N_Range
5177 Target_Typ : constant Entity_Id :=
5178 Etype (Target_Index);
5182 (Scalar_Range (Etype (Subt_Index)),
5185 Defining_Identifier (N));
5187 -- Reset Has_Dynamic_Range_Check on the subtype to
5188 -- prevent elision of the index check due to a dynamic
5189 -- check generated for a preceding index (needed since
5190 -- Insert_Range_Checks tries to avoid generating
5191 -- redundant checks on a given declaration).
5193 Set_Has_Dynamic_Range_Check (N, False);
5199 Sloc (Defining_Identifier (N)));
5201 -- Record whether this index involved a dynamic check
5204 Has_Dyn_Chk or else Has_Dynamic_Range_Check (N);
5208 Next_Index (Subt_Index);
5209 Next_Index (Target_Index);
5212 -- Finally, mark whether the subtype involves dynamic checks
5214 Set_Has_Dynamic_Range_Check (N, Has_Dyn_Chk);
5219 -- A type invariant applies to any subtype in its scope, in particular
5220 -- to a generic actual.
5222 if Has_Invariants (T) and then In_Open_Scopes (Scope (T)) then
5223 Set_Has_Invariants (Id);
5224 Set_Invariant_Procedure (Id, Invariant_Procedure (T));
5227 -- Make sure that generic actual types are properly frozen. The subtype
5228 -- is marked as a generic actual type when the enclosing instance is
5229 -- analyzed, so here we identify the subtype from the tree structure.
5232 and then Is_Generic_Actual_Type (Id)
5233 and then In_Instance
5234 and then not Comes_From_Source (N)
5235 and then Nkind (Subtype_Indication (N)) /= N_Subtype_Indication
5236 and then Is_Frozen (T)
5238 Freeze_Before (N, Id);
5241 Set_Optimize_Alignment_Flags (Id);
5242 Check_Eliminated (Id);
5245 if Has_Aspects (N) then
5246 Analyze_Aspect_Specifications (N, Id);
5249 Analyze_Dimension (N);
5251 -- Check No_Dynamic_Sized_Objects restriction, which disallows subtype
5252 -- indications on composite types where the constraints are dynamic.
5253 -- Note that object declarations and aggregates generate implicit
5254 -- subtype declarations, which this covers. One special case is that the
5255 -- implicitly generated "=" for discriminated types includes an
5256 -- offending subtype declaration, which is harmless, so we ignore it
5259 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5261 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
5263 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint
5264 and then not (Is_Internal (Id)
5265 and then Is_TSS (Scope (Id),
5266 TSS_Composite_Equality))
5267 and then not Within_Init_Proc
5268 and then not All_Composite_Constraints_Static (Cstr)
5270 Check_Restriction (No_Dynamic_Sized_Objects, Cstr);
5274 end Analyze_Subtype_Declaration;
5276 --------------------------------
5277 -- Analyze_Subtype_Indication --
5278 --------------------------------
5280 procedure Analyze_Subtype_Indication (N : Node_Id) is
5281 T : constant Entity_Id := Subtype_Mark (N);
5282 R : constant Node_Id := Range_Expression (Constraint (N));
5289 Set_Etype (N, Etype (R));
5290 Resolve (R, Entity (T));
5292 Set_Error_Posted (R);
5293 Set_Error_Posted (T);
5295 end Analyze_Subtype_Indication;
5297 --------------------------
5298 -- Analyze_Variant_Part --
5299 --------------------------
5301 procedure Analyze_Variant_Part (N : Node_Id) is
5302 Discr_Name : Node_Id;
5303 Discr_Type : Entity_Id;
5305 procedure Process_Variant (A : Node_Id);
5306 -- Analyze declarations for a single variant
5308 package Analyze_Variant_Choices is
5309 new Generic_Analyze_Choices (Process_Variant);
5310 use Analyze_Variant_Choices;
5312 ---------------------
5313 -- Process_Variant --
5314 ---------------------
5316 procedure Process_Variant (A : Node_Id) is
5317 CL : constant Node_Id := Component_List (A);
5319 if not Null_Present (CL) then
5320 Analyze_Declarations (Component_Items (CL));
5322 if Present (Variant_Part (CL)) then
5323 Analyze (Variant_Part (CL));
5326 end Process_Variant;
5328 -- Start of processing for Analyze_Variant_Part
5331 Discr_Name := Name (N);
5332 Analyze (Discr_Name);
5334 -- If Discr_Name bad, get out (prevent cascaded errors)
5336 if Etype (Discr_Name) = Any_Type then
5340 -- Check invalid discriminant in variant part
5342 if Ekind (Entity (Discr_Name)) /= E_Discriminant then
5343 Error_Msg_N ("invalid discriminant name in variant part", Discr_Name);
5346 Discr_Type := Etype (Entity (Discr_Name));
5348 if not Is_Discrete_Type (Discr_Type) then
5350 ("discriminant in a variant part must be of a discrete type",
5355 -- Now analyze the choices, which also analyzes the declarations that
5356 -- are associated with each choice.
5358 Analyze_Choices (Variants (N), Discr_Type);
5360 -- Note: we used to instantiate and call Check_Choices here to check
5361 -- that the choices covered the discriminant, but it's too early to do
5362 -- that because of statically predicated subtypes, whose analysis may
5363 -- be deferred to their freeze point which may be as late as the freeze
5364 -- point of the containing record. So this call is now to be found in
5365 -- Freeze_Record_Declaration.
5367 end Analyze_Variant_Part;
5369 ----------------------------
5370 -- Array_Type_Declaration --
5371 ----------------------------
5373 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is
5374 Component_Def : constant Node_Id := Component_Definition (Def);
5375 Component_Typ : constant Node_Id := Subtype_Indication (Component_Def);
5376 Element_Type : Entity_Id;
5377 Implicit_Base : Entity_Id;
5379 Related_Id : Entity_Id := Empty;
5381 P : constant Node_Id := Parent (Def);
5385 if Nkind (Def) = N_Constrained_Array_Definition then
5386 Index := First (Discrete_Subtype_Definitions (Def));
5388 Index := First (Subtype_Marks (Def));
5391 -- Find proper names for the implicit types which may be public. In case
5392 -- of anonymous arrays we use the name of the first object of that type
5396 Related_Id := Defining_Identifier (P);
5402 while Present (Index) loop
5405 -- Test for odd case of trying to index a type by the type itself
5407 if Is_Entity_Name (Index) and then Entity (Index) = T then
5408 Error_Msg_N ("type& cannot be indexed by itself", Index);
5409 Set_Entity (Index, Standard_Boolean);
5410 Set_Etype (Index, Standard_Boolean);
5413 -- Check SPARK restriction requiring a subtype mark
5415 if not Nkind_In (Index, N_Identifier, N_Expanded_Name) then
5416 Check_SPARK_05_Restriction ("subtype mark required", Index);
5419 -- Add a subtype declaration for each index of private array type
5420 -- declaration whose etype is also private. For example:
5423 -- type Index is private;
5425 -- type Table is array (Index) of ...
5428 -- This is currently required by the expander for the internally
5429 -- generated equality subprogram of records with variant parts in
5430 -- which the etype of some component is such private type.
5432 if Ekind (Current_Scope) = E_Package
5433 and then In_Private_Part (Current_Scope)
5434 and then Has_Private_Declaration (Etype (Index))
5437 Loc : constant Source_Ptr := Sloc (Def);
5442 New_E := Make_Temporary (Loc, 'T');
5443 Set_Is_Internal (New_E);
5446 Make_Subtype_Declaration (Loc,
5447 Defining_Identifier => New_E,
5448 Subtype_Indication =>
5449 New_Occurrence_Of (Etype (Index), Loc));
5451 Insert_Before (Parent (Def), Decl);
5453 Set_Etype (Index, New_E);
5455 -- If the index is a range the Entity attribute is not
5456 -- available. Example:
5459 -- type T is private;
5461 -- type T is new Natural;
5462 -- Table : array (T(1) .. T(10)) of Boolean;
5465 if Nkind (Index) /= N_Range then
5466 Set_Entity (Index, New_E);
5471 Make_Index (Index, P, Related_Id, Nb_Index);
5473 -- Check error of subtype with predicate for index type
5475 Bad_Predicated_Subtype_Use
5476 ("subtype& has predicate, not allowed as index subtype",
5477 Index, Etype (Index));
5479 -- Move to next index
5482 Nb_Index := Nb_Index + 1;
5485 -- Process subtype indication if one is present
5487 if Present (Component_Typ) then
5488 Element_Type := Process_Subtype (Component_Typ, P, Related_Id, 'C');
5490 Set_Etype (Component_Typ, Element_Type);
5492 if not Nkind_In (Component_Typ, N_Identifier, N_Expanded_Name) then
5493 Check_SPARK_05_Restriction
5494 ("subtype mark required", Component_Typ);
5497 -- Ada 2005 (AI-230): Access Definition case
5499 else pragma Assert (Present (Access_Definition (Component_Def)));
5501 -- Indicate that the anonymous access type is created by the
5502 -- array type declaration.
5504 Element_Type := Access_Definition
5506 N => Access_Definition (Component_Def));
5507 Set_Is_Local_Anonymous_Access (Element_Type);
5509 -- Propagate the parent. This field is needed if we have to generate
5510 -- the master_id associated with an anonymous access to task type
5511 -- component (see Expand_N_Full_Type_Declaration.Build_Master)
5513 Set_Parent (Element_Type, Parent (T));
5515 -- Ada 2005 (AI-230): In case of components that are anonymous access
5516 -- types the level of accessibility depends on the enclosing type
5519 Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230)
5521 -- Ada 2005 (AI-254)
5524 CD : constant Node_Id :=
5525 Access_To_Subprogram_Definition
5526 (Access_Definition (Component_Def));
5528 if Present (CD) and then Protected_Present (CD) then
5530 Replace_Anonymous_Access_To_Protected_Subprogram (Def);
5535 -- Constrained array case
5538 T := Create_Itype (E_Void, P, Related_Id, 'T');
5541 if Nkind (Def) = N_Constrained_Array_Definition then
5543 -- Establish Implicit_Base as unconstrained base type
5545 Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B');
5547 Set_Etype (Implicit_Base, Implicit_Base);
5548 Set_Scope (Implicit_Base, Current_Scope);
5549 Set_Has_Delayed_Freeze (Implicit_Base);
5550 Set_Default_SSO (Implicit_Base);
5552 -- The constrained array type is a subtype of the unconstrained one
5554 Set_Ekind (T, E_Array_Subtype);
5555 Init_Size_Align (T);
5556 Set_Etype (T, Implicit_Base);
5557 Set_Scope (T, Current_Scope);
5558 Set_Is_Constrained (T);
5560 First (Discrete_Subtype_Definitions (Def)));
5561 Set_Has_Delayed_Freeze (T);
5563 -- Complete setup of implicit base type
5565 Set_First_Index (Implicit_Base, First_Index (T));
5566 Set_Component_Type (Implicit_Base, Element_Type);
5567 Set_Has_Task (Implicit_Base, Has_Task (Element_Type));
5568 Set_Has_Protected (Implicit_Base, Has_Protected (Element_Type));
5569 Set_Component_Size (Implicit_Base, Uint_0);
5570 Set_Packed_Array_Impl_Type (Implicit_Base, Empty);
5571 Set_Has_Controlled_Component (Implicit_Base,
5572 Has_Controlled_Component (Element_Type)
5573 or else Is_Controlled_Active (Element_Type));
5574 Set_Finalize_Storage_Only (Implicit_Base,
5575 Finalize_Storage_Only (Element_Type));
5577 -- Inherit the "ghostness" from the constrained array type
5579 if Ghost_Mode > None or else Is_Ghost_Entity (T) then
5580 Set_Is_Ghost_Entity (Implicit_Base);
5583 -- Unconstrained array case
5586 Set_Ekind (T, E_Array_Type);
5587 Init_Size_Align (T);
5589 Set_Scope (T, Current_Scope);
5590 Set_Component_Size (T, Uint_0);
5591 Set_Is_Constrained (T, False);
5592 Set_First_Index (T, First (Subtype_Marks (Def)));
5593 Set_Has_Delayed_Freeze (T, True);
5594 Set_Has_Task (T, Has_Task (Element_Type));
5595 Set_Has_Protected (T, Has_Protected (Element_Type));
5596 Set_Has_Controlled_Component (T, Has_Controlled_Component
5599 Is_Controlled_Active (Element_Type));
5600 Set_Finalize_Storage_Only (T, Finalize_Storage_Only
5602 Set_Default_SSO (T);
5605 -- Common attributes for both cases
5607 Set_Component_Type (Base_Type (T), Element_Type);
5608 Set_Packed_Array_Impl_Type (T, Empty);
5610 if Aliased_Present (Component_Definition (Def)) then
5611 Check_SPARK_05_Restriction
5612 ("aliased is not allowed", Component_Definition (Def));
5613 Set_Has_Aliased_Components (Etype (T));
5616 -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the
5617 -- array type to ensure that objects of this type are initialized.
5619 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (Element_Type) then
5620 Set_Can_Never_Be_Null (T);
5622 if Null_Exclusion_Present (Component_Definition (Def))
5624 -- No need to check itypes because in their case this check was
5625 -- done at their point of creation
5627 and then not Is_Itype (Element_Type)
5630 ("`NOT NULL` not allowed (null already excluded)",
5631 Subtype_Indication (Component_Definition (Def)));
5635 Priv := Private_Component (Element_Type);
5637 if Present (Priv) then
5639 -- Check for circular definitions
5641 if Priv = Any_Type then
5642 Set_Component_Type (Etype (T), Any_Type);
5644 -- There is a gap in the visibility of operations on the composite
5645 -- type only if the component type is defined in a different scope.
5647 elsif Scope (Priv) = Current_Scope then
5650 elsif Is_Limited_Type (Priv) then
5651 Set_Is_Limited_Composite (Etype (T));
5652 Set_Is_Limited_Composite (T);
5654 Set_Is_Private_Composite (Etype (T));
5655 Set_Is_Private_Composite (T);
5659 -- A syntax error in the declaration itself may lead to an empty index
5660 -- list, in which case do a minimal patch.
5662 if No (First_Index (T)) then
5663 Error_Msg_N ("missing index definition in array type declaration", T);
5666 Indexes : constant List_Id :=
5667 New_List (New_Occurrence_Of (Any_Id, Sloc (T)));
5669 Set_Discrete_Subtype_Definitions (Def, Indexes);
5670 Set_First_Index (T, First (Indexes));
5675 -- Create a concatenation operator for the new type. Internal array
5676 -- types created for packed entities do not need such, they are
5677 -- compatible with the user-defined type.
5679 if Number_Dimensions (T) = 1
5680 and then not Is_Packed_Array_Impl_Type (T)
5682 New_Concatenation_Op (T);
5685 -- In the case of an unconstrained array the parser has already verified
5686 -- that all the indexes are unconstrained but we still need to make sure
5687 -- that the element type is constrained.
5689 if not Is_Definite_Subtype (Element_Type) then
5691 ("unconstrained element type in array declaration",
5692 Subtype_Indication (Component_Def));
5694 elsif Is_Abstract_Type (Element_Type) then
5696 ("the type of a component cannot be abstract",
5697 Subtype_Indication (Component_Def));
5700 -- There may be an invariant declared for the component type, but
5701 -- the construction of the component invariant checking procedure
5702 -- takes place during expansion.
5703 end Array_Type_Declaration;
5705 ------------------------------------------------------
5706 -- Replace_Anonymous_Access_To_Protected_Subprogram --
5707 ------------------------------------------------------
5709 function Replace_Anonymous_Access_To_Protected_Subprogram
5710 (N : Node_Id) return Entity_Id
5712 Loc : constant Source_Ptr := Sloc (N);
5714 Curr_Scope : constant Scope_Stack_Entry :=
5715 Scope_Stack.Table (Scope_Stack.Last);
5717 Anon : constant Entity_Id := Make_Temporary (Loc, 'S');
5720 -- Access definition in declaration
5723 -- Object definition or formal definition with an access definition
5726 -- Declaration of anonymous access to subprogram type
5729 -- Original specification in access to subprogram
5734 Set_Is_Internal (Anon);
5737 when N_Component_Declaration |
5738 N_Unconstrained_Array_Definition |
5739 N_Constrained_Array_Definition =>
5740 Comp := Component_Definition (N);
5741 Acc := Access_Definition (Comp);
5743 when N_Discriminant_Specification =>
5744 Comp := Discriminant_Type (N);
5747 when N_Parameter_Specification =>
5748 Comp := Parameter_Type (N);
5751 when N_Access_Function_Definition =>
5752 Comp := Result_Definition (N);
5755 when N_Object_Declaration =>
5756 Comp := Object_Definition (N);
5759 when N_Function_Specification =>
5760 Comp := Result_Definition (N);
5764 raise Program_Error;
5767 Spec := Access_To_Subprogram_Definition (Acc);
5770 Make_Full_Type_Declaration (Loc,
5771 Defining_Identifier => Anon,
5772 Type_Definition => Copy_Separate_Tree (Spec));
5774 Mark_Rewrite_Insertion (Decl);
5776 -- In ASIS mode, analyze the profile on the original node, because
5777 -- the separate copy does not provide enough links to recover the
5778 -- original tree. Analysis is limited to type annotations, within
5779 -- a temporary scope that serves as an anonymous subprogram to collect
5780 -- otherwise useless temporaries and itypes.
5784 Typ : constant Entity_Id := Make_Temporary (Loc, 'S');
5787 if Nkind (Spec) = N_Access_Function_Definition then
5788 Set_Ekind (Typ, E_Function);
5790 Set_Ekind (Typ, E_Procedure);
5793 Set_Parent (Typ, N);
5794 Set_Scope (Typ, Current_Scope);
5797 -- Nothing to do if procedure is parameterless
5799 if Present (Parameter_Specifications (Spec)) then
5800 Process_Formals (Parameter_Specifications (Spec), Spec);
5803 if Nkind (Spec) = N_Access_Function_Definition then
5805 Def : constant Node_Id := Result_Definition (Spec);
5808 -- The result might itself be an anonymous access type, so
5811 if Nkind (Def) = N_Access_Definition then
5812 if Present (Access_To_Subprogram_Definition (Def)) then
5815 Replace_Anonymous_Access_To_Protected_Subprogram
5818 Find_Type (Subtype_Mark (Def));
5831 -- Insert the new declaration in the nearest enclosing scope. If the
5832 -- node is a body and N is its return type, the declaration belongs in
5833 -- the enclosing scope.
5837 if Nkind (P) = N_Subprogram_Body
5838 and then Nkind (N) = N_Function_Specification
5843 while Present (P) and then not Has_Declarations (P) loop
5847 pragma Assert (Present (P));
5849 if Nkind (P) = N_Package_Specification then
5850 Prepend (Decl, Visible_Declarations (P));
5852 Prepend (Decl, Declarations (P));
5855 -- Replace the anonymous type with an occurrence of the new declaration.
5856 -- In all cases the rewritten node does not have the null-exclusion
5857 -- attribute because (if present) it was already inherited by the
5858 -- anonymous entity (Anon). Thus, in case of components we do not
5859 -- inherit this attribute.
5861 if Nkind (N) = N_Parameter_Specification then
5862 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5863 Set_Etype (Defining_Identifier (N), Anon);
5864 Set_Null_Exclusion_Present (N, False);
5866 elsif Nkind (N) = N_Object_Declaration then
5867 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5868 Set_Etype (Defining_Identifier (N), Anon);
5870 elsif Nkind (N) = N_Access_Function_Definition then
5871 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5873 elsif Nkind (N) = N_Function_Specification then
5874 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5875 Set_Etype (Defining_Unit_Name (N), Anon);
5879 Make_Component_Definition (Loc,
5880 Subtype_Indication => New_Occurrence_Of (Anon, Loc)));
5883 Mark_Rewrite_Insertion (Comp);
5885 if Nkind_In (N, N_Object_Declaration, N_Access_Function_Definition)
5886 or else (Nkind (Parent (N)) = N_Full_Type_Declaration
5887 and then not Is_Type (Current_Scope))
5890 -- Declaration can be analyzed in the current scope.
5895 -- Temporarily remove the current scope (record or subprogram) from
5896 -- the stack to add the new declarations to the enclosing scope.
5897 -- The anonymous entity is an Itype with the proper attributes.
5899 Scope_Stack.Decrement_Last;
5901 Set_Is_Itype (Anon);
5902 Set_Associated_Node_For_Itype (Anon, N);
5903 Scope_Stack.Append (Curr_Scope);
5906 Set_Ekind (Anon, E_Anonymous_Access_Protected_Subprogram_Type);
5907 Set_Can_Use_Internal_Rep (Anon, not Always_Compatible_Rep_On_Target);
5909 end Replace_Anonymous_Access_To_Protected_Subprogram;
5911 -------------------------------
5912 -- Build_Derived_Access_Type --
5913 -------------------------------
5915 procedure Build_Derived_Access_Type
5917 Parent_Type : Entity_Id;
5918 Derived_Type : Entity_Id)
5920 S : constant Node_Id := Subtype_Indication (Type_Definition (N));
5922 Desig_Type : Entity_Id;
5924 Discr_Con_Elist : Elist_Id;
5925 Discr_Con_El : Elmt_Id;
5929 -- Set the designated type so it is available in case this is an access
5930 -- to a self-referential type, e.g. a standard list type with a next
5931 -- pointer. Will be reset after subtype is built.
5933 Set_Directly_Designated_Type
5934 (Derived_Type, Designated_Type (Parent_Type));
5936 Subt := Process_Subtype (S, N);
5938 if Nkind (S) /= N_Subtype_Indication
5939 and then Subt /= Base_Type (Subt)
5941 Set_Ekind (Derived_Type, E_Access_Subtype);
5944 if Ekind (Derived_Type) = E_Access_Subtype then
5946 Pbase : constant Entity_Id := Base_Type (Parent_Type);
5947 Ibase : constant Entity_Id :=
5948 Create_Itype (Ekind (Pbase), N, Derived_Type, 'B');
5949 Svg_Chars : constant Name_Id := Chars (Ibase);
5950 Svg_Next_E : constant Entity_Id := Next_Entity (Ibase);
5953 Copy_Node (Pbase, Ibase);
5955 Set_Chars (Ibase, Svg_Chars);
5956 Set_Next_Entity (Ibase, Svg_Next_E);
5957 Set_Sloc (Ibase, Sloc (Derived_Type));
5958 Set_Scope (Ibase, Scope (Derived_Type));
5959 Set_Freeze_Node (Ibase, Empty);
5960 Set_Is_Frozen (Ibase, False);
5961 Set_Comes_From_Source (Ibase, False);
5962 Set_Is_First_Subtype (Ibase, False);
5964 Set_Etype (Ibase, Pbase);
5965 Set_Etype (Derived_Type, Ibase);
5969 Set_Directly_Designated_Type
5970 (Derived_Type, Designated_Type (Subt));
5972 Set_Is_Constrained (Derived_Type, Is_Constrained (Subt));
5973 Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type));
5974 Set_Size_Info (Derived_Type, Parent_Type);
5975 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
5976 Set_Depends_On_Private (Derived_Type,
5977 Has_Private_Component (Derived_Type));
5978 Conditional_Delay (Derived_Type, Subt);
5980 -- Ada 2005 (AI-231): Set the null-exclusion attribute, and verify
5981 -- that it is not redundant.
5983 if Null_Exclusion_Present (Type_Definition (N)) then
5984 Set_Can_Never_Be_Null (Derived_Type);
5986 -- What is with the "AND THEN FALSE" here ???
5988 if Can_Never_Be_Null (Parent_Type)
5992 ("`NOT NULL` not allowed (& already excludes null)",
5996 elsif Can_Never_Be_Null (Parent_Type) then
5997 Set_Can_Never_Be_Null (Derived_Type);
6000 -- Note: we do not copy the Storage_Size_Variable, since we always go to
6001 -- the root type for this information.
6003 -- Apply range checks to discriminants for derived record case
6004 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
6006 Desig_Type := Designated_Type (Derived_Type);
6007 if Is_Composite_Type (Desig_Type)
6008 and then (not Is_Array_Type (Desig_Type))
6009 and then Has_Discriminants (Desig_Type)
6010 and then Base_Type (Desig_Type) /= Desig_Type
6012 Discr_Con_Elist := Discriminant_Constraint (Desig_Type);
6013 Discr_Con_El := First_Elmt (Discr_Con_Elist);
6015 Discr := First_Discriminant (Base_Type (Desig_Type));
6016 while Present (Discr_Con_El) loop
6017 Apply_Range_Check (Node (Discr_Con_El), Etype (Discr));
6018 Next_Elmt (Discr_Con_El);
6019 Next_Discriminant (Discr);
6022 end Build_Derived_Access_Type;
6024 ------------------------------
6025 -- Build_Derived_Array_Type --
6026 ------------------------------
6028 procedure Build_Derived_Array_Type
6030 Parent_Type : Entity_Id;
6031 Derived_Type : Entity_Id)
6033 Loc : constant Source_Ptr := Sloc (N);
6034 Tdef : constant Node_Id := Type_Definition (N);
6035 Indic : constant Node_Id := Subtype_Indication (Tdef);
6036 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
6037 Implicit_Base : Entity_Id;
6038 New_Indic : Node_Id;
6040 procedure Make_Implicit_Base;
6041 -- If the parent subtype is constrained, the derived type is a subtype
6042 -- of an implicit base type derived from the parent base.
6044 ------------------------
6045 -- Make_Implicit_Base --
6046 ------------------------
6048 procedure Make_Implicit_Base is
6051 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
6053 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
6054 Set_Etype (Implicit_Base, Parent_Base);
6056 Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base);
6057 Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base);
6059 Set_Has_Delayed_Freeze (Implicit_Base, True);
6061 -- Inherit the "ghostness" from the parent base type
6063 if Ghost_Mode > None or else Is_Ghost_Entity (Parent_Base) then
6064 Set_Is_Ghost_Entity (Implicit_Base);
6066 end Make_Implicit_Base;
6068 -- Start of processing for Build_Derived_Array_Type
6071 if not Is_Constrained (Parent_Type) then
6072 if Nkind (Indic) /= N_Subtype_Indication then
6073 Set_Ekind (Derived_Type, E_Array_Type);
6075 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
6076 Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type);
6078 Set_Has_Delayed_Freeze (Derived_Type, True);
6082 Set_Etype (Derived_Type, Implicit_Base);
6085 Make_Subtype_Declaration (Loc,
6086 Defining_Identifier => Derived_Type,
6087 Subtype_Indication =>
6088 Make_Subtype_Indication (Loc,
6089 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6090 Constraint => Constraint (Indic)));
6092 Rewrite (N, New_Indic);
6097 if Nkind (Indic) /= N_Subtype_Indication then
6100 Set_Ekind (Derived_Type, Ekind (Parent_Type));
6101 Set_Etype (Derived_Type, Implicit_Base);
6102 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
6105 Error_Msg_N ("illegal constraint on constrained type", Indic);
6109 -- If parent type is not a derived type itself, and is declared in
6110 -- closed scope (e.g. a subprogram), then we must explicitly introduce
6111 -- the new type's concatenation operator since Derive_Subprograms
6112 -- will not inherit the parent's operator. If the parent type is
6113 -- unconstrained, the operator is of the unconstrained base type.
6115 if Number_Dimensions (Parent_Type) = 1
6116 and then not Is_Limited_Type (Parent_Type)
6117 and then not Is_Derived_Type (Parent_Type)
6118 and then not Is_Package_Or_Generic_Package
6119 (Scope (Base_Type (Parent_Type)))
6121 if not Is_Constrained (Parent_Type)
6122 and then Is_Constrained (Derived_Type)
6124 New_Concatenation_Op (Implicit_Base);
6126 New_Concatenation_Op (Derived_Type);
6129 end Build_Derived_Array_Type;
6131 -----------------------------------
6132 -- Build_Derived_Concurrent_Type --
6133 -----------------------------------
6135 procedure Build_Derived_Concurrent_Type
6137 Parent_Type : Entity_Id;
6138 Derived_Type : Entity_Id)
6140 Loc : constant Source_Ptr := Sloc (N);
6142 Corr_Record : constant Entity_Id := Make_Temporary (Loc, 'C');
6143 Corr_Decl : Node_Id;
6144 Corr_Decl_Needed : Boolean;
6145 -- If the derived type has fewer discriminants than its parent, the
6146 -- corresponding record is also a derived type, in order to account for
6147 -- the bound discriminants. We create a full type declaration for it in
6150 Constraint_Present : constant Boolean :=
6151 Nkind (Subtype_Indication (Type_Definition (N))) =
6152 N_Subtype_Indication;
6154 D_Constraint : Node_Id;
6155 New_Constraint : Elist_Id;
6156 Old_Disc : Entity_Id;
6157 New_Disc : Entity_Id;
6161 Set_Stored_Constraint (Derived_Type, No_Elist);
6162 Corr_Decl_Needed := False;
6165 if Present (Discriminant_Specifications (N))
6166 and then Constraint_Present
6168 Old_Disc := First_Discriminant (Parent_Type);
6169 New_Disc := First (Discriminant_Specifications (N));
6170 while Present (New_Disc) and then Present (Old_Disc) loop
6171 Next_Discriminant (Old_Disc);
6176 if Present (Old_Disc) and then Expander_Active then
6178 -- The new type has fewer discriminants, so we need to create a new
6179 -- corresponding record, which is derived from the corresponding
6180 -- record of the parent, and has a stored constraint that captures
6181 -- the values of the discriminant constraints. The corresponding
6182 -- record is needed only if expander is active and code generation is
6185 -- The type declaration for the derived corresponding record has the
6186 -- same discriminant part and constraints as the current declaration.
6187 -- Copy the unanalyzed tree to build declaration.
6189 Corr_Decl_Needed := True;
6190 New_N := Copy_Separate_Tree (N);
6193 Make_Full_Type_Declaration (Loc,
6194 Defining_Identifier => Corr_Record,
6195 Discriminant_Specifications =>
6196 Discriminant_Specifications (New_N),
6198 Make_Derived_Type_Definition (Loc,
6199 Subtype_Indication =>
6200 Make_Subtype_Indication (Loc,
6203 (Corresponding_Record_Type (Parent_Type), Loc),
6206 (Subtype_Indication (Type_Definition (New_N))))));
6209 -- Copy Storage_Size and Relative_Deadline variables if task case
6211 if Is_Task_Type (Parent_Type) then
6212 Set_Storage_Size_Variable (Derived_Type,
6213 Storage_Size_Variable (Parent_Type));
6214 Set_Relative_Deadline_Variable (Derived_Type,
6215 Relative_Deadline_Variable (Parent_Type));
6218 if Present (Discriminant_Specifications (N)) then
6219 Push_Scope (Derived_Type);
6220 Check_Or_Process_Discriminants (N, Derived_Type);
6222 if Constraint_Present then
6224 Expand_To_Stored_Constraint
6226 Build_Discriminant_Constraints
6228 Subtype_Indication (Type_Definition (N)), True));
6233 elsif Constraint_Present then
6235 -- Build constrained subtype, copying the constraint, and derive
6236 -- from it to create a derived constrained type.
6239 Loc : constant Source_Ptr := Sloc (N);
6240 Anon : constant Entity_Id :=
6241 Make_Defining_Identifier (Loc,
6242 Chars => New_External_Name (Chars (Derived_Type), 'T'));
6247 Make_Subtype_Declaration (Loc,
6248 Defining_Identifier => Anon,
6249 Subtype_Indication =>
6250 New_Copy_Tree (Subtype_Indication (Type_Definition (N))));
6251 Insert_Before (N, Decl);
6254 Rewrite (Subtype_Indication (Type_Definition (N)),
6255 New_Occurrence_Of (Anon, Loc));
6256 Set_Analyzed (Derived_Type, False);
6262 -- By default, operations and private data are inherited from parent.
6263 -- However, in the presence of bound discriminants, a new corresponding
6264 -- record will be created, see below.
6266 Set_Has_Discriminants
6267 (Derived_Type, Has_Discriminants (Parent_Type));
6268 Set_Corresponding_Record_Type
6269 (Derived_Type, Corresponding_Record_Type (Parent_Type));
6271 -- Is_Constrained is set according the parent subtype, but is set to
6272 -- False if the derived type is declared with new discriminants.
6276 (Is_Constrained (Parent_Type) or else Constraint_Present)
6277 and then not Present (Discriminant_Specifications (N)));
6279 if Constraint_Present then
6280 if not Has_Discriminants (Parent_Type) then
6281 Error_Msg_N ("untagged parent must have discriminants", N);
6283 elsif Present (Discriminant_Specifications (N)) then
6285 -- Verify that new discriminants are used to constrain old ones
6290 (Constraint (Subtype_Indication (Type_Definition (N)))));
6292 Old_Disc := First_Discriminant (Parent_Type);
6294 while Present (D_Constraint) loop
6295 if Nkind (D_Constraint) /= N_Discriminant_Association then
6297 -- Positional constraint. If it is a reference to a new
6298 -- discriminant, it constrains the corresponding old one.
6300 if Nkind (D_Constraint) = N_Identifier then
6301 New_Disc := First_Discriminant (Derived_Type);
6302 while Present (New_Disc) loop
6303 exit when Chars (New_Disc) = Chars (D_Constraint);
6304 Next_Discriminant (New_Disc);
6307 if Present (New_Disc) then
6308 Set_Corresponding_Discriminant (New_Disc, Old_Disc);
6312 Next_Discriminant (Old_Disc);
6314 -- if this is a named constraint, search by name for the old
6315 -- discriminants constrained by the new one.
6317 elsif Nkind (Expression (D_Constraint)) = N_Identifier then
6319 -- Find new discriminant with that name
6321 New_Disc := First_Discriminant (Derived_Type);
6322 while Present (New_Disc) loop
6324 Chars (New_Disc) = Chars (Expression (D_Constraint));
6325 Next_Discriminant (New_Disc);
6328 if Present (New_Disc) then
6330 -- Verify that new discriminant renames some discriminant
6331 -- of the parent type, and associate the new discriminant
6332 -- with one or more old ones that it renames.
6338 Selector := First (Selector_Names (D_Constraint));
6339 while Present (Selector) loop
6340 Old_Disc := First_Discriminant (Parent_Type);
6341 while Present (Old_Disc) loop
6342 exit when Chars (Old_Disc) = Chars (Selector);
6343 Next_Discriminant (Old_Disc);
6346 if Present (Old_Disc) then
6347 Set_Corresponding_Discriminant
6348 (New_Disc, Old_Disc);
6357 Next (D_Constraint);
6360 New_Disc := First_Discriminant (Derived_Type);
6361 while Present (New_Disc) loop
6362 if No (Corresponding_Discriminant (New_Disc)) then
6364 ("new discriminant& must constrain old one", N, New_Disc);
6367 Subtypes_Statically_Compatible
6369 Etype (Corresponding_Discriminant (New_Disc)))
6372 ("& not statically compatible with parent discriminant",
6376 Next_Discriminant (New_Disc);
6380 elsif Present (Discriminant_Specifications (N)) then
6382 ("missing discriminant constraint in untagged derivation", N);
6385 -- The entity chain of the derived type includes the new discriminants
6386 -- but shares operations with the parent.
6388 if Present (Discriminant_Specifications (N)) then
6389 Old_Disc := First_Discriminant (Parent_Type);
6390 while Present (Old_Disc) loop
6391 if No (Next_Entity (Old_Disc))
6392 or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant
6395 (Last_Entity (Derived_Type), Next_Entity (Old_Disc));
6399 Next_Discriminant (Old_Disc);
6403 Set_First_Entity (Derived_Type, First_Entity (Parent_Type));
6404 if Has_Discriminants (Parent_Type) then
6405 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6406 Set_Discriminant_Constraint (
6407 Derived_Type, Discriminant_Constraint (Parent_Type));
6411 Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type));
6413 Set_Has_Completion (Derived_Type);
6415 if Corr_Decl_Needed then
6416 Set_Stored_Constraint (Derived_Type, New_Constraint);
6417 Insert_After (N, Corr_Decl);
6418 Analyze (Corr_Decl);
6419 Set_Corresponding_Record_Type (Derived_Type, Corr_Record);
6421 end Build_Derived_Concurrent_Type;
6423 ------------------------------------
6424 -- Build_Derived_Enumeration_Type --
6425 ------------------------------------
6427 procedure Build_Derived_Enumeration_Type
6429 Parent_Type : Entity_Id;
6430 Derived_Type : Entity_Id)
6432 Loc : constant Source_Ptr := Sloc (N);
6433 Def : constant Node_Id := Type_Definition (N);
6434 Indic : constant Node_Id := Subtype_Indication (Def);
6435 Implicit_Base : Entity_Id;
6436 Literal : Entity_Id;
6437 New_Lit : Entity_Id;
6438 Literals_List : List_Id;
6439 Type_Decl : Node_Id;
6441 Rang_Expr : Node_Id;
6444 -- Since types Standard.Character and Standard.[Wide_]Wide_Character do
6445 -- not have explicit literals lists we need to process types derived
6446 -- from them specially. This is handled by Derived_Standard_Character.
6447 -- If the parent type is a generic type, there are no literals either,
6448 -- and we construct the same skeletal representation as for the generic
6451 if Is_Standard_Character_Type (Parent_Type) then
6452 Derived_Standard_Character (N, Parent_Type, Derived_Type);
6454 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
6460 if Nkind (Indic) /= N_Subtype_Indication then
6462 Make_Attribute_Reference (Loc,
6463 Attribute_Name => Name_First,
6464 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6465 Set_Etype (Lo, Derived_Type);
6468 Make_Attribute_Reference (Loc,
6469 Attribute_Name => Name_Last,
6470 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6471 Set_Etype (Hi, Derived_Type);
6473 Set_Scalar_Range (Derived_Type,
6479 -- Analyze subtype indication and verify compatibility
6480 -- with parent type.
6482 if Base_Type (Process_Subtype (Indic, N)) /=
6483 Base_Type (Parent_Type)
6486 ("illegal constraint for formal discrete type", N);
6492 -- If a constraint is present, analyze the bounds to catch
6493 -- premature usage of the derived literals.
6495 if Nkind (Indic) = N_Subtype_Indication
6496 and then Nkind (Range_Expression (Constraint (Indic))) = N_Range
6498 Analyze (Low_Bound (Range_Expression (Constraint (Indic))));
6499 Analyze (High_Bound (Range_Expression (Constraint (Indic))));
6502 -- Introduce an implicit base type for the derived type even if there
6503 -- is no constraint attached to it, since this seems closer to the
6504 -- Ada semantics. Build a full type declaration tree for the derived
6505 -- type using the implicit base type as the defining identifier. The
6506 -- build a subtype declaration tree which applies the constraint (if
6507 -- any) have it replace the derived type declaration.
6509 Literal := First_Literal (Parent_Type);
6510 Literals_List := New_List;
6511 while Present (Literal)
6512 and then Ekind (Literal) = E_Enumeration_Literal
6514 -- Literals of the derived type have the same representation as
6515 -- those of the parent type, but this representation can be
6516 -- overridden by an explicit representation clause. Indicate
6517 -- that there is no explicit representation given yet. These
6518 -- derived literals are implicit operations of the new type,
6519 -- and can be overridden by explicit ones.
6521 if Nkind (Literal) = N_Defining_Character_Literal then
6523 Make_Defining_Character_Literal (Loc, Chars (Literal));
6525 New_Lit := Make_Defining_Identifier (Loc, Chars (Literal));
6528 Set_Ekind (New_Lit, E_Enumeration_Literal);
6529 Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal));
6530 Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal));
6531 Set_Enumeration_Rep_Expr (New_Lit, Empty);
6532 Set_Alias (New_Lit, Literal);
6533 Set_Is_Known_Valid (New_Lit, True);
6535 Append (New_Lit, Literals_List);
6536 Next_Literal (Literal);
6540 Make_Defining_Identifier (Sloc (Derived_Type),
6541 Chars => New_External_Name (Chars (Derived_Type), 'B'));
6543 -- Indicate the proper nature of the derived type. This must be done
6544 -- before analysis of the literals, to recognize cases when a literal
6545 -- may be hidden by a previous explicit function definition (cf.
6548 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
6549 Set_Etype (Derived_Type, Implicit_Base);
6552 Make_Full_Type_Declaration (Loc,
6553 Defining_Identifier => Implicit_Base,
6554 Discriminant_Specifications => No_List,
6556 Make_Enumeration_Type_Definition (Loc, Literals_List));
6558 Mark_Rewrite_Insertion (Type_Decl);
6559 Insert_Before (N, Type_Decl);
6560 Analyze (Type_Decl);
6562 -- The anonymous base now has a full declaration, but this base
6563 -- is not a first subtype.
6565 Set_Is_First_Subtype (Implicit_Base, False);
6567 -- After the implicit base is analyzed its Etype needs to be changed
6568 -- to reflect the fact that it is derived from the parent type which
6569 -- was ignored during analysis. We also set the size at this point.
6571 Set_Etype (Implicit_Base, Parent_Type);
6573 Set_Size_Info (Implicit_Base, Parent_Type);
6574 Set_RM_Size (Implicit_Base, RM_Size (Parent_Type));
6575 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type));
6577 -- Copy other flags from parent type
6579 Set_Has_Non_Standard_Rep
6580 (Implicit_Base, Has_Non_Standard_Rep
6582 Set_Has_Pragma_Ordered
6583 (Implicit_Base, Has_Pragma_Ordered
6585 Set_Has_Delayed_Freeze (Implicit_Base);
6587 -- Process the subtype indication including a validation check on the
6588 -- constraint, if any. If a constraint is given, its bounds must be
6589 -- implicitly converted to the new type.
6591 if Nkind (Indic) = N_Subtype_Indication then
6593 R : constant Node_Id :=
6594 Range_Expression (Constraint (Indic));
6597 if Nkind (R) = N_Range then
6598 Hi := Build_Scalar_Bound
6599 (High_Bound (R), Parent_Type, Implicit_Base);
6600 Lo := Build_Scalar_Bound
6601 (Low_Bound (R), Parent_Type, Implicit_Base);
6604 -- Constraint is a Range attribute. Replace with explicit
6605 -- mention of the bounds of the prefix, which must be a
6608 Analyze (Prefix (R));
6610 Convert_To (Implicit_Base,
6611 Make_Attribute_Reference (Loc,
6612 Attribute_Name => Name_Last,
6614 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6617 Convert_To (Implicit_Base,
6618 Make_Attribute_Reference (Loc,
6619 Attribute_Name => Name_First,
6621 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6628 (Type_High_Bound (Parent_Type),
6629 Parent_Type, Implicit_Base);
6632 (Type_Low_Bound (Parent_Type),
6633 Parent_Type, Implicit_Base);
6641 -- If we constructed a default range for the case where no range
6642 -- was given, then the expressions in the range must not freeze
6643 -- since they do not correspond to expressions in the source.
6645 if Nkind (Indic) /= N_Subtype_Indication then
6646 Set_Must_Not_Freeze (Lo);
6647 Set_Must_Not_Freeze (Hi);
6648 Set_Must_Not_Freeze (Rang_Expr);
6652 Make_Subtype_Declaration (Loc,
6653 Defining_Identifier => Derived_Type,
6654 Subtype_Indication =>
6655 Make_Subtype_Indication (Loc,
6656 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6658 Make_Range_Constraint (Loc,
6659 Range_Expression => Rang_Expr))));
6663 -- Propagate the aspects from the original type declaration to the
6664 -- declaration of the implicit base.
6666 Move_Aspects (From => Original_Node (N), To => Type_Decl);
6668 -- Apply a range check. Since this range expression doesn't have an
6669 -- Etype, we have to specifically pass the Source_Typ parameter. Is
6672 if Nkind (Indic) = N_Subtype_Indication then
6674 (Range_Expression (Constraint (Indic)), Parent_Type,
6675 Source_Typ => Entity (Subtype_Mark (Indic)));
6678 end Build_Derived_Enumeration_Type;
6680 --------------------------------
6681 -- Build_Derived_Numeric_Type --
6682 --------------------------------
6684 procedure Build_Derived_Numeric_Type
6686 Parent_Type : Entity_Id;
6687 Derived_Type : Entity_Id)
6689 Loc : constant Source_Ptr := Sloc (N);
6690 Tdef : constant Node_Id := Type_Definition (N);
6691 Indic : constant Node_Id := Subtype_Indication (Tdef);
6692 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
6693 No_Constraint : constant Boolean := Nkind (Indic) /=
6694 N_Subtype_Indication;
6695 Implicit_Base : Entity_Id;
6701 -- Process the subtype indication including a validation check on
6702 -- the constraint if any.
6704 Discard_Node (Process_Subtype (Indic, N));
6706 -- Introduce an implicit base type for the derived type even if there
6707 -- is no constraint attached to it, since this seems closer to the Ada
6711 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
6713 Set_Etype (Implicit_Base, Parent_Base);
6714 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
6715 Set_Size_Info (Implicit_Base, Parent_Base);
6716 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base));
6717 Set_Parent (Implicit_Base, Parent (Derived_Type));
6718 Set_Is_Known_Valid (Implicit_Base, Is_Known_Valid (Parent_Base));
6720 -- Set RM Size for discrete type or decimal fixed-point type
6721 -- Ordinary fixed-point is excluded, why???
6723 if Is_Discrete_Type (Parent_Base)
6724 or else Is_Decimal_Fixed_Point_Type (Parent_Base)
6726 Set_RM_Size (Implicit_Base, RM_Size (Parent_Base));
6729 Set_Has_Delayed_Freeze (Implicit_Base);
6731 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
6732 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
6734 Set_Scalar_Range (Implicit_Base,
6739 if Has_Infinities (Parent_Base) then
6740 Set_Includes_Infinities (Scalar_Range (Implicit_Base));
6743 -- The Derived_Type, which is the entity of the declaration, is a
6744 -- subtype of the implicit base. Its Ekind is a subtype, even in the
6745 -- absence of an explicit constraint.
6747 Set_Etype (Derived_Type, Implicit_Base);
6749 -- If we did not have a constraint, then the Ekind is set from the
6750 -- parent type (otherwise Process_Subtype has set the bounds)
6752 if No_Constraint then
6753 Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type)));
6756 -- If we did not have a range constraint, then set the range from the
6757 -- parent type. Otherwise, the Process_Subtype call has set the bounds.
6759 if No_Constraint or else not Has_Range_Constraint (Indic) then
6760 Set_Scalar_Range (Derived_Type,
6762 Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)),
6763 High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type))));
6764 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6766 if Has_Infinities (Parent_Type) then
6767 Set_Includes_Infinities (Scalar_Range (Derived_Type));
6770 Set_Is_Known_Valid (Derived_Type, Is_Known_Valid (Parent_Type));
6773 Set_Is_Descendent_Of_Address (Derived_Type,
6774 Is_Descendent_Of_Address (Parent_Type));
6775 Set_Is_Descendent_Of_Address (Implicit_Base,
6776 Is_Descendent_Of_Address (Parent_Type));
6778 -- Set remaining type-specific fields, depending on numeric type
6780 if Is_Modular_Integer_Type (Parent_Type) then
6781 Set_Modulus (Implicit_Base, Modulus (Parent_Base));
6783 Set_Non_Binary_Modulus
6784 (Implicit_Base, Non_Binary_Modulus (Parent_Base));
6787 (Implicit_Base, Is_Known_Valid (Parent_Base));
6789 elsif Is_Floating_Point_Type (Parent_Type) then
6791 -- Digits of base type is always copied from the digits value of
6792 -- the parent base type, but the digits of the derived type will
6793 -- already have been set if there was a constraint present.
6795 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6796 Set_Float_Rep (Implicit_Base, Float_Rep (Parent_Base));
6798 if No_Constraint then
6799 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type));
6802 elsif Is_Fixed_Point_Type (Parent_Type) then
6804 -- Small of base type and derived type are always copied from the
6805 -- parent base type, since smalls never change. The delta of the
6806 -- base type is also copied from the parent base type. However the
6807 -- delta of the derived type will have been set already if a
6808 -- constraint was present.
6810 Set_Small_Value (Derived_Type, Small_Value (Parent_Base));
6811 Set_Small_Value (Implicit_Base, Small_Value (Parent_Base));
6812 Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base));
6814 if No_Constraint then
6815 Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type));
6818 -- The scale and machine radix in the decimal case are always
6819 -- copied from the parent base type.
6821 if Is_Decimal_Fixed_Point_Type (Parent_Type) then
6822 Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base));
6823 Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base));
6825 Set_Machine_Radix_10
6826 (Derived_Type, Machine_Radix_10 (Parent_Base));
6827 Set_Machine_Radix_10
6828 (Implicit_Base, Machine_Radix_10 (Parent_Base));
6830 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6832 if No_Constraint then
6833 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base));
6836 -- the analysis of the subtype_indication sets the
6837 -- digits value of the derived type.
6844 if Is_Integer_Type (Parent_Type) then
6845 Set_Has_Shift_Operator
6846 (Implicit_Base, Has_Shift_Operator (Parent_Type));
6849 -- The type of the bounds is that of the parent type, and they
6850 -- must be converted to the derived type.
6852 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
6854 -- The implicit_base should be frozen when the derived type is frozen,
6855 -- but note that it is used in the conversions of the bounds. For fixed
6856 -- types we delay the determination of the bounds until the proper
6857 -- freezing point. For other numeric types this is rejected by GCC, for
6858 -- reasons that are currently unclear (???), so we choose to freeze the
6859 -- implicit base now. In the case of integers and floating point types
6860 -- this is harmless because subsequent representation clauses cannot
6861 -- affect anything, but it is still baffling that we cannot use the
6862 -- same mechanism for all derived numeric types.
6864 -- There is a further complication: actually some representation
6865 -- clauses can affect the implicit base type. For example, attribute
6866 -- definition clauses for stream-oriented attributes need to set the
6867 -- corresponding TSS entries on the base type, and this normally
6868 -- cannot be done after the base type is frozen, so the circuitry in
6869 -- Sem_Ch13.New_Stream_Subprogram must account for this possibility
6870 -- and not use Set_TSS in this case.
6872 -- There are also consequences for the case of delayed representation
6873 -- aspects for some cases. For example, a Size aspect is delayed and
6874 -- should not be evaluated to the freeze point. This early freezing
6875 -- means that the size attribute evaluation happens too early???
6877 if Is_Fixed_Point_Type (Parent_Type) then
6878 Conditional_Delay (Implicit_Base, Parent_Type);
6880 Freeze_Before (N, Implicit_Base);
6882 end Build_Derived_Numeric_Type;
6884 --------------------------------
6885 -- Build_Derived_Private_Type --
6886 --------------------------------
6888 procedure Build_Derived_Private_Type
6890 Parent_Type : Entity_Id;
6891 Derived_Type : Entity_Id;
6892 Is_Completion : Boolean;
6893 Derive_Subps : Boolean := True)
6895 Loc : constant Source_Ptr := Sloc (N);
6896 Par_Base : constant Entity_Id := Base_Type (Parent_Type);
6897 Par_Scope : constant Entity_Id := Scope (Par_Base);
6898 Full_N : constant Node_Id := New_Copy_Tree (N);
6899 Full_Der : Entity_Id := New_Copy (Derived_Type);
6902 procedure Build_Full_Derivation;
6903 -- Build full derivation, i.e. derive from the full view
6905 procedure Copy_And_Build;
6906 -- Copy derived type declaration, replace parent with its full view,
6907 -- and build derivation
6909 ---------------------------
6910 -- Build_Full_Derivation --
6911 ---------------------------
6913 procedure Build_Full_Derivation is
6915 -- If parent scope is not open, install the declarations
6917 if not In_Open_Scopes (Par_Scope) then
6918 Install_Private_Declarations (Par_Scope);
6919 Install_Visible_Declarations (Par_Scope);
6921 Uninstall_Declarations (Par_Scope);
6923 -- If parent scope is open and in another unit, and parent has a
6924 -- completion, then the derivation is taking place in the visible
6925 -- part of a child unit. In that case retrieve the full view of
6926 -- the parent momentarily.
6928 elsif not In_Same_Source_Unit (N, Parent_Type) then
6929 Full_P := Full_View (Parent_Type);
6930 Exchange_Declarations (Parent_Type);
6932 Exchange_Declarations (Full_P);
6934 -- Otherwise it is a local derivation
6939 end Build_Full_Derivation;
6941 --------------------
6942 -- Copy_And_Build --
6943 --------------------
6945 procedure Copy_And_Build is
6946 Full_Parent : Entity_Id := Parent_Type;
6949 -- If the parent is itself derived from another private type,
6950 -- installing the private declarations has not affected its
6951 -- privacy status, so use its own full view explicitly.
6953 if Is_Private_Type (Full_Parent)
6954 and then Present (Full_View (Full_Parent))
6956 Full_Parent := Full_View (Full_Parent);
6959 -- And its underlying full view if necessary
6961 if Is_Private_Type (Full_Parent)
6962 and then Present (Underlying_Full_View (Full_Parent))
6964 Full_Parent := Underlying_Full_View (Full_Parent);
6967 -- For record, access and most enumeration types, derivation from
6968 -- the full view requires a fully-fledged declaration. In the other
6969 -- cases, just use an itype.
6971 if Ekind (Full_Parent) in Record_Kind
6972 or else Ekind (Full_Parent) in Access_Kind
6974 (Ekind (Full_Parent) in Enumeration_Kind
6975 and then not Is_Standard_Character_Type (Full_Parent)
6976 and then not Is_Generic_Type (Root_Type (Full_Parent)))
6978 -- Copy and adjust declaration to provide a completion for what
6979 -- is originally a private declaration. Indicate that full view
6980 -- is internally generated.
6982 Set_Comes_From_Source (Full_N, False);
6983 Set_Comes_From_Source (Full_Der, False);
6984 Set_Parent (Full_Der, Full_N);
6985 Set_Defining_Identifier (Full_N, Full_Der);
6987 -- If there are no constraints, adjust the subtype mark
6989 if Nkind (Subtype_Indication (Type_Definition (Full_N))) /=
6990 N_Subtype_Indication
6992 Set_Subtype_Indication
6993 (Type_Definition (Full_N),
6994 New_Occurrence_Of (Full_Parent, Sloc (Full_N)));
6997 Insert_After (N, Full_N);
6999 -- Build full view of derived type from full view of parent which
7000 -- is now installed. Subprograms have been derived on the partial
7001 -- view, the completion does not derive them anew.
7003 if Ekind (Full_Parent) in Record_Kind then
7005 -- If parent type is tagged, the completion inherits the proper
7006 -- primitive operations.
7008 if Is_Tagged_Type (Parent_Type) then
7009 Build_Derived_Record_Type
7010 (Full_N, Full_Parent, Full_Der, Derive_Subps);
7012 Build_Derived_Record_Type
7013 (Full_N, Full_Parent, Full_Der, Derive_Subps => False);
7018 (Full_N, Full_Parent, Full_Der,
7019 Is_Completion => False, Derive_Subps => False);
7022 -- The full declaration has been introduced into the tree and
7023 -- processed in the step above. It should not be analyzed again
7024 -- (when encountered later in the current list of declarations)
7025 -- to prevent spurious name conflicts. The full entity remains
7028 Set_Analyzed (Full_N);
7032 Make_Defining_Identifier (Sloc (Derived_Type),
7033 Chars => Chars (Derived_Type));
7034 Set_Is_Itype (Full_Der);
7035 Set_Associated_Node_For_Itype (Full_Der, N);
7036 Set_Parent (Full_Der, N);
7038 (N, Full_Parent, Full_Der,
7039 Is_Completion => False, Derive_Subps => False);
7042 Set_Has_Private_Declaration (Full_Der);
7043 Set_Has_Private_Declaration (Derived_Type);
7045 Set_Scope (Full_Der, Scope (Derived_Type));
7046 Set_Is_First_Subtype (Full_Der, Is_First_Subtype (Derived_Type));
7047 Set_Has_Size_Clause (Full_Der, False);
7048 Set_Has_Alignment_Clause (Full_Der, False);
7049 Set_Has_Delayed_Freeze (Full_Der);
7050 Set_Is_Frozen (Full_Der, False);
7051 Set_Freeze_Node (Full_Der, Empty);
7052 Set_Depends_On_Private (Full_Der, Has_Private_Component (Full_Der));
7053 Set_Is_Public (Full_Der, Is_Public (Derived_Type));
7055 -- The convention on the base type may be set in the private part
7056 -- and not propagated to the subtype until later, so we obtain the
7057 -- convention from the base type of the parent.
7059 Set_Convention (Full_Der, Convention (Base_Type (Full_Parent)));
7062 -- Start of processing for Build_Derived_Private_Type
7065 if Is_Tagged_Type (Parent_Type) then
7066 Full_P := Full_View (Parent_Type);
7068 -- A type extension of a type with unknown discriminants is an
7069 -- indefinite type that the back-end cannot handle directly.
7070 -- We treat it as a private type, and build a completion that is
7071 -- derived from the full view of the parent, and hopefully has
7072 -- known discriminants.
7074 -- If the full view of the parent type has an underlying record view,
7075 -- use it to generate the underlying record view of this derived type
7076 -- (required for chains of derivations with unknown discriminants).
7078 -- Minor optimization: we avoid the generation of useless underlying
7079 -- record view entities if the private type declaration has unknown
7080 -- discriminants but its corresponding full view has no
7083 if Has_Unknown_Discriminants (Parent_Type)
7084 and then Present (Full_P)
7085 and then (Has_Discriminants (Full_P)
7086 or else Present (Underlying_Record_View (Full_P)))
7087 and then not In_Open_Scopes (Par_Scope)
7088 and then Expander_Active
7091 Full_Der : constant Entity_Id := Make_Temporary (Loc, 'T');
7092 New_Ext : constant Node_Id :=
7094 (Record_Extension_Part (Type_Definition (N)));
7098 Build_Derived_Record_Type
7099 (N, Parent_Type, Derived_Type, Derive_Subps);
7101 -- Build anonymous completion, as a derivation from the full
7102 -- view of the parent. This is not a completion in the usual
7103 -- sense, because the current type is not private.
7106 Make_Full_Type_Declaration (Loc,
7107 Defining_Identifier => Full_Der,
7109 Make_Derived_Type_Definition (Loc,
7110 Subtype_Indication =>
7112 (Subtype_Indication (Type_Definition (N))),
7113 Record_Extension_Part => New_Ext));
7115 -- If the parent type has an underlying record view, use it
7116 -- here to build the new underlying record view.
7118 if Present (Underlying_Record_View (Full_P)) then
7120 (Nkind (Subtype_Indication (Type_Definition (Decl)))
7122 Set_Entity (Subtype_Indication (Type_Definition (Decl)),
7123 Underlying_Record_View (Full_P));
7126 Install_Private_Declarations (Par_Scope);
7127 Install_Visible_Declarations (Par_Scope);
7128 Insert_Before (N, Decl);
7130 -- Mark entity as an underlying record view before analysis,
7131 -- to avoid generating the list of its primitive operations
7132 -- (which is not really required for this entity) and thus
7133 -- prevent spurious errors associated with missing overriding
7134 -- of abstract primitives (overridden only for Derived_Type).
7136 Set_Ekind (Full_Der, E_Record_Type);
7137 Set_Is_Underlying_Record_View (Full_Der);
7138 Set_Default_SSO (Full_Der);
7142 pragma Assert (Has_Discriminants (Full_Der)
7143 and then not Has_Unknown_Discriminants (Full_Der));
7145 Uninstall_Declarations (Par_Scope);
7147 -- Freeze the underlying record view, to prevent generation of
7148 -- useless dispatching information, which is simply shared with
7149 -- the real derived type.
7151 Set_Is_Frozen (Full_Der);
7153 -- If the derived type has access discriminants, create
7154 -- references to their anonymous types now, to prevent
7155 -- back-end problems when their first use is in generated
7156 -- bodies of primitives.
7162 E := First_Entity (Full_Der);
7164 while Present (E) loop
7165 if Ekind (E) = E_Discriminant
7166 and then Ekind (Etype (E)) = E_Anonymous_Access_Type
7168 Build_Itype_Reference (Etype (E), Decl);
7175 -- Set up links between real entity and underlying record view
7177 Set_Underlying_Record_View (Derived_Type, Base_Type (Full_Der));
7178 Set_Underlying_Record_View (Base_Type (Full_Der), Derived_Type);
7181 -- If discriminants are known, build derived record
7184 Build_Derived_Record_Type
7185 (N, Parent_Type, Derived_Type, Derive_Subps);
7190 elsif Has_Discriminants (Parent_Type) then
7192 -- Build partial view of derived type from partial view of parent.
7193 -- This must be done before building the full derivation because the
7194 -- second derivation will modify the discriminants of the first and
7195 -- the discriminants are chained with the rest of the components in
7196 -- the full derivation.
7198 Build_Derived_Record_Type
7199 (N, Parent_Type, Derived_Type, Derive_Subps);
7201 -- Build the full derivation if this is not the anonymous derived
7202 -- base type created by Build_Derived_Record_Type in the constrained
7203 -- case (see point 5. of its head comment) since we build it for the
7204 -- derived subtype. And skip it for protected types altogether, as
7205 -- gigi does not use these types directly.
7207 if Present (Full_View (Parent_Type))
7208 and then not Is_Itype (Derived_Type)
7209 and then not (Ekind (Full_View (Parent_Type)) in Protected_Kind)
7212 Der_Base : constant Entity_Id := Base_Type (Derived_Type);
7214 Last_Discr : Entity_Id;
7217 -- If this is not a completion, construct the implicit full
7218 -- view by deriving from the full view of the parent type.
7219 -- But if this is a completion, the derived private type
7220 -- being built is a full view and the full derivation can
7221 -- only be its underlying full view.
7223 Build_Full_Derivation;
7225 if not Is_Completion then
7226 Set_Full_View (Derived_Type, Full_Der);
7228 Set_Underlying_Full_View (Derived_Type, Full_Der);
7231 if not Is_Base_Type (Derived_Type) then
7232 Set_Full_View (Der_Base, Base_Type (Full_Der));
7235 -- Copy the discriminant list from full view to the partial
7236 -- view (base type and its subtype). Gigi requires that the
7237 -- partial and full views have the same discriminants.
7239 -- Note that since the partial view points to discriminants
7240 -- in the full view, their scope will be that of the full
7241 -- view. This might cause some front end problems and need
7244 Discr := First_Discriminant (Base_Type (Full_Der));
7245 Set_First_Entity (Der_Base, Discr);
7248 Last_Discr := Discr;
7249 Next_Discriminant (Discr);
7250 exit when No (Discr);
7253 Set_Last_Entity (Der_Base, Last_Discr);
7254 Set_First_Entity (Derived_Type, First_Entity (Der_Base));
7255 Set_Last_Entity (Derived_Type, Last_Entity (Der_Base));
7257 Set_Stored_Constraint
7258 (Full_Der, Stored_Constraint (Derived_Type));
7262 elsif Present (Full_View (Parent_Type))
7263 and then Has_Discriminants (Full_View (Parent_Type))
7265 if Has_Unknown_Discriminants (Parent_Type)
7266 and then Nkind (Subtype_Indication (Type_Definition (N))) =
7267 N_Subtype_Indication
7270 ("cannot constrain type with unknown discriminants",
7271 Subtype_Indication (Type_Definition (N)));
7275 -- If this is not a completion, construct the implicit full view by
7276 -- deriving from the full view of the parent type. But if this is a
7277 -- completion, the derived private type being built is a full view
7278 -- and the full derivation can only be its underlying full view.
7280 Build_Full_Derivation;
7282 if not Is_Completion then
7283 Set_Full_View (Derived_Type, Full_Der);
7285 Set_Underlying_Full_View (Derived_Type, Full_Der);
7288 -- In any case, the primitive operations are inherited from the
7289 -- parent type, not from the internal full view.
7291 Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type));
7293 if Derive_Subps then
7294 Derive_Subprograms (Parent_Type, Derived_Type);
7297 Set_Stored_Constraint (Derived_Type, No_Elist);
7299 (Derived_Type, Is_Constrained (Full_View (Parent_Type)));
7302 -- Untagged type, No discriminants on either view
7304 if Nkind (Subtype_Indication (Type_Definition (N))) =
7305 N_Subtype_Indication
7308 ("illegal constraint on type without discriminants", N);
7311 if Present (Discriminant_Specifications (N))
7312 and then Present (Full_View (Parent_Type))
7313 and then not Is_Tagged_Type (Full_View (Parent_Type))
7315 Error_Msg_N ("cannot add discriminants to untagged type", N);
7318 Set_Stored_Constraint (Derived_Type, No_Elist);
7319 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
7320 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
7321 Set_Disable_Controlled (Derived_Type, Disable_Controlled
7323 Set_Has_Controlled_Component
7324 (Derived_Type, Has_Controlled_Component
7327 -- Direct controlled types do not inherit Finalize_Storage_Only flag
7329 if not Is_Controlled_Active (Parent_Type) then
7330 Set_Finalize_Storage_Only
7331 (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type));
7334 -- If this is not a completion, construct the implicit full view by
7335 -- deriving from the full view of the parent type.
7337 -- ??? If the parent is untagged private and its completion is
7338 -- tagged, this mechanism will not work because we cannot derive from
7339 -- the tagged full view unless we have an extension.
7341 if Present (Full_View (Parent_Type))
7342 and then not Is_Tagged_Type (Full_View (Parent_Type))
7343 and then not Is_Completion
7345 Build_Full_Derivation;
7346 Set_Full_View (Derived_Type, Full_Der);
7350 Set_Has_Unknown_Discriminants (Derived_Type,
7351 Has_Unknown_Discriminants (Parent_Type));
7353 if Is_Private_Type (Derived_Type) then
7354 Set_Private_Dependents (Derived_Type, New_Elmt_List);
7357 -- If the parent base type is in scope, add the derived type to its
7358 -- list of private dependents, because its full view may become
7359 -- visible subsequently (in a nested private part, a body, or in a
7360 -- further child unit).
7362 if Is_Private_Type (Par_Base) and then In_Open_Scopes (Par_Scope) then
7363 Append_Elmt (Derived_Type, Private_Dependents (Parent_Type));
7365 -- Check for unusual case where a type completed by a private
7366 -- derivation occurs within a package nested in a child unit, and
7367 -- the parent is declared in an ancestor.
7369 if Is_Child_Unit (Scope (Current_Scope))
7370 and then Is_Completion
7371 and then In_Private_Part (Current_Scope)
7372 and then Scope (Parent_Type) /= Current_Scope
7374 -- Note that if the parent has a completion in the private part,
7375 -- (which is itself a derivation from some other private type)
7376 -- it is that completion that is visible, there is no full view
7377 -- available, and no special processing is needed.
7379 and then Present (Full_View (Parent_Type))
7381 -- In this case, the full view of the parent type will become
7382 -- visible in the body of the enclosing child, and only then will
7383 -- the current type be possibly non-private. Build an underlying
7384 -- full view that will be installed when the enclosing child body
7387 if Present (Underlying_Full_View (Derived_Type)) then
7388 Full_Der := Underlying_Full_View (Derived_Type);
7390 Build_Full_Derivation;
7391 Set_Underlying_Full_View (Derived_Type, Full_Der);
7394 -- The full view will be used to swap entities on entry/exit to
7395 -- the body, and must appear in the entity list for the package.
7397 Append_Entity (Full_Der, Scope (Derived_Type));
7400 end Build_Derived_Private_Type;
7402 -------------------------------
7403 -- Build_Derived_Record_Type --
7404 -------------------------------
7408 -- Ideally we would like to use the same model of type derivation for
7409 -- tagged and untagged record types. Unfortunately this is not quite
7410 -- possible because the semantics of representation clauses is different
7411 -- for tagged and untagged records under inheritance. Consider the
7414 -- type R (...) is [tagged] record ... end record;
7415 -- type T (...) is new R (...) [with ...];
7417 -- The representation clauses for T can specify a completely different
7418 -- record layout from R's. Hence the same component can be placed in two
7419 -- very different positions in objects of type T and R. If R and T are
7420 -- tagged types, representation clauses for T can only specify the layout
7421 -- of non inherited components, thus components that are common in R and T
7422 -- have the same position in objects of type R and T.
7424 -- This has two implications. The first is that the entire tree for R's
7425 -- declaration needs to be copied for T in the untagged case, so that T
7426 -- can be viewed as a record type of its own with its own representation
7427 -- clauses. The second implication is the way we handle discriminants.
7428 -- Specifically, in the untagged case we need a way to communicate to Gigi
7429 -- what are the real discriminants in the record, while for the semantics
7430 -- we need to consider those introduced by the user to rename the
7431 -- discriminants in the parent type. This is handled by introducing the
7432 -- notion of stored discriminants. See below for more.
7434 -- Fortunately the way regular components are inherited can be handled in
7435 -- the same way in tagged and untagged types.
7437 -- To complicate things a bit more the private view of a private extension
7438 -- cannot be handled in the same way as the full view (for one thing the
7439 -- semantic rules are somewhat different). We will explain what differs
7442 -- 2. DISCRIMINANTS UNDER INHERITANCE
7444 -- The semantic rules governing the discriminants of derived types are
7447 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
7448 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
7450 -- If parent type has discriminants, then the discriminants that are
7451 -- declared in the derived type are [3.4 (11)]:
7453 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
7456 -- o Otherwise, each discriminant of the parent type (implicitly declared
7457 -- in the same order with the same specifications). In this case, the
7458 -- discriminants are said to be "inherited", or if unknown in the parent
7459 -- are also unknown in the derived type.
7461 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
7463 -- o The parent subtype must be constrained;
7465 -- o If the parent type is not a tagged type, then each discriminant of
7466 -- the derived type must be used in the constraint defining a parent
7467 -- subtype. [Implementation note: This ensures that the new discriminant
7468 -- can share storage with an existing discriminant.]
7470 -- For the derived type each discriminant of the parent type is either
7471 -- inherited, constrained to equal some new discriminant of the derived
7472 -- type, or constrained to the value of an expression.
7474 -- When inherited or constrained to equal some new discriminant, the
7475 -- parent discriminant and the discriminant of the derived type are said
7478 -- If a discriminant of the parent type is constrained to a specific value
7479 -- in the derived type definition, then the discriminant is said to be
7480 -- "specified" by that derived type definition.
7482 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES
7484 -- We have spoken about stored discriminants in point 1 (introduction)
7485 -- above. There are two sort of stored discriminants: implicit and
7486 -- explicit. As long as the derived type inherits the same discriminants as
7487 -- the root record type, stored discriminants are the same as regular
7488 -- discriminants, and are said to be implicit. However, if any discriminant
7489 -- in the root type was renamed in the derived type, then the derived
7490 -- type will contain explicit stored discriminants. Explicit stored
7491 -- discriminants are discriminants in addition to the semantically visible
7492 -- discriminants defined for the derived type. Stored discriminants are
7493 -- used by Gigi to figure out what are the physical discriminants in
7494 -- objects of the derived type (see precise definition in einfo.ads).
7495 -- As an example, consider the following:
7497 -- type R (D1, D2, D3 : Int) is record ... end record;
7498 -- type T1 is new R;
7499 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
7500 -- type T3 is new T2;
7501 -- type T4 (Y : Int) is new T3 (Y, 99);
7503 -- The following table summarizes the discriminants and stored
7504 -- discriminants in R and T1 through T4.
7506 -- Type Discrim Stored Discrim Comment
7507 -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R
7508 -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1
7509 -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2
7510 -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3
7511 -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4
7513 -- Field Corresponding_Discriminant (abbreviated CD below) allows us to
7514 -- find the corresponding discriminant in the parent type, while
7515 -- Original_Record_Component (abbreviated ORC below), the actual physical
7516 -- component that is renamed. Finally the field Is_Completely_Hidden
7517 -- (abbreviated ICH below) is set for all explicit stored discriminants
7518 -- (see einfo.ads for more info). For the above example this gives:
7520 -- Discrim CD ORC ICH
7521 -- ^^^^^^^ ^^ ^^^ ^^^
7522 -- D1 in R empty itself no
7523 -- D2 in R empty itself no
7524 -- D3 in R empty itself no
7526 -- D1 in T1 D1 in R itself no
7527 -- D2 in T1 D2 in R itself no
7528 -- D3 in T1 D3 in R itself no
7530 -- X1 in T2 D3 in T1 D3 in T2 no
7531 -- X2 in T2 D1 in T1 D1 in T2 no
7532 -- D1 in T2 empty itself yes
7533 -- D2 in T2 empty itself yes
7534 -- D3 in T2 empty itself yes
7536 -- X1 in T3 X1 in T2 D3 in T3 no
7537 -- X2 in T3 X2 in T2 D1 in T3 no
7538 -- D1 in T3 empty itself yes
7539 -- D2 in T3 empty itself yes
7540 -- D3 in T3 empty itself yes
7542 -- Y in T4 X1 in T3 D3 in T3 no
7543 -- D1 in T3 empty itself yes
7544 -- D2 in T3 empty itself yes
7545 -- D3 in T3 empty itself yes
7547 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES
7549 -- Type derivation for tagged types is fairly straightforward. If no
7550 -- discriminants are specified by the derived type, these are inherited
7551 -- from the parent. No explicit stored discriminants are ever necessary.
7552 -- The only manipulation that is done to the tree is that of adding a
7553 -- _parent field with parent type and constrained to the same constraint
7554 -- specified for the parent in the derived type definition. For instance:
7556 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
7557 -- type T1 is new R with null record;
7558 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
7560 -- are changed into:
7562 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
7563 -- _parent : R (D1, D2, D3);
7566 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
7567 -- _parent : T1 (X2, 88, X1);
7570 -- The discriminants actually present in R, T1 and T2 as well as their CD,
7571 -- ORC and ICH fields are:
7573 -- Discrim CD ORC ICH
7574 -- ^^^^^^^ ^^ ^^^ ^^^
7575 -- D1 in R empty itself no
7576 -- D2 in R empty itself no
7577 -- D3 in R empty itself no
7579 -- D1 in T1 D1 in R D1 in R no
7580 -- D2 in T1 D2 in R D2 in R no
7581 -- D3 in T1 D3 in R D3 in R no
7583 -- X1 in T2 D3 in T1 D3 in R no
7584 -- X2 in T2 D1 in T1 D1 in R no
7586 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS
7588 -- Regardless of whether we dealing with a tagged or untagged type
7589 -- we will transform all derived type declarations of the form
7591 -- type T is new R (...) [with ...];
7593 -- subtype S is R (...);
7594 -- type T is new S [with ...];
7596 -- type BT is new R [with ...];
7597 -- subtype T is BT (...);
7599 -- That is, the base derived type is constrained only if it has no
7600 -- discriminants. The reason for doing this is that GNAT's semantic model
7601 -- assumes that a base type with discriminants is unconstrained.
7603 -- Note that, strictly speaking, the above transformation is not always
7604 -- correct. Consider for instance the following excerpt from ACVC b34011a:
7606 -- procedure B34011A is
7607 -- type REC (D : integer := 0) is record
7612 -- type T6 is new Rec;
7613 -- function F return T6;
7618 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
7621 -- The definition of Q6.U is illegal. However transforming Q6.U into
7623 -- type BaseU is new T6;
7624 -- subtype U is BaseU (Q6.F.I)
7626 -- turns U into a legal subtype, which is incorrect. To avoid this problem
7627 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
7628 -- the transformation described above.
7630 -- There is another instance where the above transformation is incorrect.
7634 -- type Base (D : Integer) is tagged null record;
7635 -- procedure P (X : Base);
7637 -- type Der is new Base (2) with null record;
7638 -- procedure P (X : Der);
7641 -- Then the above transformation turns this into
7643 -- type Der_Base is new Base with null record;
7644 -- -- procedure P (X : Base) is implicitly inherited here
7645 -- -- as procedure P (X : Der_Base).
7647 -- subtype Der is Der_Base (2);
7648 -- procedure P (X : Der);
7649 -- -- The overriding of P (X : Der_Base) is illegal since we
7650 -- -- have a parameter conformance problem.
7652 -- To get around this problem, after having semantically processed Der_Base
7653 -- and the rewritten subtype declaration for Der, we copy Der_Base field
7654 -- Discriminant_Constraint from Der so that when parameter conformance is
7655 -- checked when P is overridden, no semantic errors are flagged.
7657 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS
7659 -- Regardless of whether we are dealing with a tagged or untagged type
7660 -- we will transform all derived type declarations of the form
7662 -- type R (D1, .., Dn : ...) is [tagged] record ...;
7663 -- type T is new R [with ...];
7665 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
7667 -- The reason for such transformation is that it allows us to implement a
7668 -- very clean form of component inheritance as explained below.
7670 -- Note that this transformation is not achieved by direct tree rewriting
7671 -- and manipulation, but rather by redoing the semantic actions that the
7672 -- above transformation will entail. This is done directly in routine
7673 -- Inherit_Components.
7675 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE
7677 -- In both tagged and untagged derived types, regular non discriminant
7678 -- components are inherited in the derived type from the parent type. In
7679 -- the absence of discriminants component, inheritance is straightforward
7680 -- as components can simply be copied from the parent.
7682 -- If the parent has discriminants, inheriting components constrained with
7683 -- these discriminants requires caution. Consider the following example:
7685 -- type R (D1, D2 : Positive) is [tagged] record
7686 -- S : String (D1 .. D2);
7689 -- type T1 is new R [with null record];
7690 -- type T2 (X : positive) is new R (1, X) [with null record];
7692 -- As explained in 6. above, T1 is rewritten as
7693 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
7694 -- which makes the treatment for T1 and T2 identical.
7696 -- What we want when inheriting S, is that references to D1 and D2 in R are
7697 -- replaced with references to their correct constraints, i.e. D1 and D2 in
7698 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
7699 -- with either discriminant references in the derived type or expressions.
7700 -- This replacement is achieved as follows: before inheriting R's
7701 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
7702 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
7703 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
7704 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
7705 -- by String (1 .. X).
7707 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS
7709 -- We explain here the rules governing private type extensions relevant to
7710 -- type derivation. These rules are explained on the following example:
7712 -- type D [(...)] is new A [(...)] with private; <-- partial view
7713 -- type D [(...)] is new P [(...)] with null record; <-- full view
7715 -- Type A is called the ancestor subtype of the private extension.
7716 -- Type P is the parent type of the full view of the private extension. It
7717 -- must be A or a type derived from A.
7719 -- The rules concerning the discriminants of private type extensions are
7722 -- o If a private extension inherits known discriminants from the ancestor
7723 -- subtype, then the full view must also inherit its discriminants from
7724 -- the ancestor subtype and the parent subtype of the full view must be
7725 -- constrained if and only if the ancestor subtype is constrained.
7727 -- o If a partial view has unknown discriminants, then the full view may
7728 -- define a definite or an indefinite subtype, with or without
7731 -- o If a partial view has neither known nor unknown discriminants, then
7732 -- the full view must define a definite subtype.
7734 -- o If the ancestor subtype of a private extension has constrained
7735 -- discriminants, then the parent subtype of the full view must impose a
7736 -- statically matching constraint on those discriminants.
7738 -- This means that only the following forms of private extensions are
7741 -- type D is new A with private; <-- partial view
7742 -- type D is new P with null record; <-- full view
7744 -- If A has no discriminants than P has no discriminants, otherwise P must
7745 -- inherit A's discriminants.
7747 -- type D is new A (...) with private; <-- partial view
7748 -- type D is new P (:::) with null record; <-- full view
7750 -- P must inherit A's discriminants and (...) and (:::) must statically
7753 -- subtype A is R (...);
7754 -- type D is new A with private; <-- partial view
7755 -- type D is new P with null record; <-- full view
7757 -- P must have inherited R's discriminants and must be derived from A or
7758 -- any of its subtypes.
7760 -- type D (..) is new A with private; <-- partial view
7761 -- type D (..) is new P [(:::)] with null record; <-- full view
7763 -- No specific constraints on P's discriminants or constraint (:::).
7764 -- Note that A can be unconstrained, but the parent subtype P must either
7765 -- be constrained or (:::) must be present.
7767 -- type D (..) is new A [(...)] with private; <-- partial view
7768 -- type D (..) is new P [(:::)] with null record; <-- full view
7770 -- P's constraints on A's discriminants must statically match those
7771 -- imposed by (...).
7773 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS
7775 -- The full view of a private extension is handled exactly as described
7776 -- above. The model chose for the private view of a private extension is
7777 -- the same for what concerns discriminants (i.e. they receive the same
7778 -- treatment as in the tagged case). However, the private view of the
7779 -- private extension always inherits the components of the parent base,
7780 -- without replacing any discriminant reference. Strictly speaking this is
7781 -- incorrect. However, Gigi never uses this view to generate code so this
7782 -- is a purely semantic issue. In theory, a set of transformations similar
7783 -- to those given in 5. and 6. above could be applied to private views of
7784 -- private extensions to have the same model of component inheritance as
7785 -- for non private extensions. However, this is not done because it would
7786 -- further complicate private type processing. Semantically speaking, this
7787 -- leaves us in an uncomfortable situation. As an example consider:
7790 -- type R (D : integer) is tagged record
7791 -- S : String (1 .. D);
7793 -- procedure P (X : R);
7794 -- type T is new R (1) with private;
7796 -- type T is new R (1) with null record;
7799 -- This is transformed into:
7802 -- type R (D : integer) is tagged record
7803 -- S : String (1 .. D);
7805 -- procedure P (X : R);
7806 -- type T is new R (1) with private;
7808 -- type BaseT is new R with null record;
7809 -- subtype T is BaseT (1);
7812 -- (strictly speaking the above is incorrect Ada)
7814 -- From the semantic standpoint the private view of private extension T
7815 -- should be flagged as constrained since one can clearly have
7819 -- in a unit withing Pack. However, when deriving subprograms for the
7820 -- private view of private extension T, T must be seen as unconstrained
7821 -- since T has discriminants (this is a constraint of the current
7822 -- subprogram derivation model). Thus, when processing the private view of
7823 -- a private extension such as T, we first mark T as unconstrained, we
7824 -- process it, we perform program derivation and just before returning from
7825 -- Build_Derived_Record_Type we mark T as constrained.
7827 -- ??? Are there are other uncomfortable cases that we will have to
7830 -- 10. RECORD_TYPE_WITH_PRIVATE complications
7832 -- Types that are derived from a visible record type and have a private
7833 -- extension present other peculiarities. They behave mostly like private
7834 -- types, but if they have primitive operations defined, these will not
7835 -- have the proper signatures for further inheritance, because other
7836 -- primitive operations will use the implicit base that we define for
7837 -- private derivations below. This affect subprogram inheritance (see
7838 -- Derive_Subprograms for details). We also derive the implicit base from
7839 -- the base type of the full view, so that the implicit base is a record
7840 -- type and not another private type, This avoids infinite loops.
7842 procedure Build_Derived_Record_Type
7844 Parent_Type : Entity_Id;
7845 Derived_Type : Entity_Id;
7846 Derive_Subps : Boolean := True)
7848 Discriminant_Specs : constant Boolean :=
7849 Present (Discriminant_Specifications (N));
7850 Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type);
7851 Loc : constant Source_Ptr := Sloc (N);
7852 Private_Extension : constant Boolean :=
7853 Nkind (N) = N_Private_Extension_Declaration;
7854 Assoc_List : Elist_Id;
7855 Constraint_Present : Boolean;
7857 Discrim : Entity_Id;
7859 Inherit_Discrims : Boolean := False;
7860 Last_Discrim : Entity_Id;
7861 New_Base : Entity_Id;
7863 New_Discrs : Elist_Id;
7864 New_Indic : Node_Id;
7865 Parent_Base : Entity_Id;
7866 Save_Etype : Entity_Id;
7867 Save_Discr_Constr : Elist_Id;
7868 Save_Next_Entity : Entity_Id;
7871 Discs : Elist_Id := New_Elmt_List;
7872 -- An empty Discs list means that there were no constraints in the
7873 -- subtype indication or that there was an error processing it.
7876 if Ekind (Parent_Type) = E_Record_Type_With_Private
7877 and then Present (Full_View (Parent_Type))
7878 and then Has_Discriminants (Parent_Type)
7880 Parent_Base := Base_Type (Full_View (Parent_Type));
7882 Parent_Base := Base_Type (Parent_Type);
7885 -- AI05-0115 : if this is a derivation from a private type in some
7886 -- other scope that may lead to invisible components for the derived
7887 -- type, mark it accordingly.
7889 if Is_Private_Type (Parent_Type) then
7890 if Scope (Parent_Type) = Scope (Derived_Type) then
7893 elsif In_Open_Scopes (Scope (Parent_Type))
7894 and then In_Private_Part (Scope (Parent_Type))
7899 Set_Has_Private_Ancestor (Derived_Type);
7903 Set_Has_Private_Ancestor
7904 (Derived_Type, Has_Private_Ancestor (Parent_Type));
7907 -- Before we start the previously documented transformations, here is
7908 -- little fix for size and alignment of tagged types. Normally when we
7909 -- derive type D from type P, we copy the size and alignment of P as the
7910 -- default for D, and in the absence of explicit representation clauses
7911 -- for D, the size and alignment are indeed the same as the parent.
7913 -- But this is wrong for tagged types, since fields may be added, and
7914 -- the default size may need to be larger, and the default alignment may
7915 -- need to be larger.
7917 -- We therefore reset the size and alignment fields in the tagged case.
7918 -- Note that the size and alignment will in any case be at least as
7919 -- large as the parent type (since the derived type has a copy of the
7920 -- parent type in the _parent field)
7922 -- The type is also marked as being tagged here, which is needed when
7923 -- processing components with a self-referential anonymous access type
7924 -- in the call to Check_Anonymous_Access_Components below. Note that
7925 -- this flag is also set later on for completeness.
7928 Set_Is_Tagged_Type (Derived_Type);
7929 Init_Size_Align (Derived_Type);
7932 -- STEP 0a: figure out what kind of derived type declaration we have
7934 if Private_Extension then
7936 Set_Ekind (Derived_Type, E_Record_Type_With_Private);
7937 Set_Default_SSO (Derived_Type);
7940 Type_Def := Type_Definition (N);
7942 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
7943 -- Parent_Base can be a private type or private extension. However,
7944 -- for tagged types with an extension the newly added fields are
7945 -- visible and hence the Derived_Type is always an E_Record_Type.
7946 -- (except that the parent may have its own private fields).
7947 -- For untagged types we preserve the Ekind of the Parent_Base.
7949 if Present (Record_Extension_Part (Type_Def)) then
7950 Set_Ekind (Derived_Type, E_Record_Type);
7951 Set_Default_SSO (Derived_Type);
7953 -- Create internal access types for components with anonymous
7956 if Ada_Version >= Ada_2005 then
7957 Check_Anonymous_Access_Components
7958 (N, Derived_Type, Derived_Type,
7959 Component_List (Record_Extension_Part (Type_Def)));
7963 Set_Ekind (Derived_Type, Ekind (Parent_Base));
7967 -- Indic can either be an N_Identifier if the subtype indication
7968 -- contains no constraint or an N_Subtype_Indication if the subtype
7969 -- indication has a constraint.
7971 Indic := Subtype_Indication (Type_Def);
7972 Constraint_Present := (Nkind (Indic) = N_Subtype_Indication);
7974 -- Check that the type has visible discriminants. The type may be
7975 -- a private type with unknown discriminants whose full view has
7976 -- discriminants which are invisible.
7978 if Constraint_Present then
7979 if not Has_Discriminants (Parent_Base)
7981 (Has_Unknown_Discriminants (Parent_Base)
7982 and then Is_Private_Type (Parent_Base))
7985 ("invalid constraint: type has no discriminant",
7986 Constraint (Indic));
7988 Constraint_Present := False;
7989 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7991 elsif Is_Constrained (Parent_Type) then
7993 ("invalid constraint: parent type is already constrained",
7994 Constraint (Indic));
7996 Constraint_Present := False;
7997 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
8001 -- STEP 0b: If needed, apply transformation given in point 5. above
8003 if not Private_Extension
8004 and then Has_Discriminants (Parent_Type)
8005 and then not Discriminant_Specs
8006 and then (Is_Constrained (Parent_Type) or else Constraint_Present)
8008 -- First, we must analyze the constraint (see comment in point 5.)
8009 -- The constraint may come from the subtype indication of the full
8012 if Constraint_Present then
8013 New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic);
8015 -- If there is no explicit constraint, there might be one that is
8016 -- inherited from a constrained parent type. In that case verify that
8017 -- it conforms to the constraint in the partial view. In perverse
8018 -- cases the parent subtypes of the partial and full view can have
8019 -- different constraints.
8021 elsif Present (Stored_Constraint (Parent_Type)) then
8022 New_Discrs := Stored_Constraint (Parent_Type);
8025 New_Discrs := No_Elist;
8028 if Has_Discriminants (Derived_Type)
8029 and then Has_Private_Declaration (Derived_Type)
8030 and then Present (Discriminant_Constraint (Derived_Type))
8031 and then Present (New_Discrs)
8033 -- Verify that constraints of the full view statically match
8034 -- those given in the partial view.
8040 C1 := First_Elmt (New_Discrs);
8041 C2 := First_Elmt (Discriminant_Constraint (Derived_Type));
8042 while Present (C1) and then Present (C2) loop
8043 if Fully_Conformant_Expressions (Node (C1), Node (C2))
8045 (Is_OK_Static_Expression (Node (C1))
8046 and then Is_OK_Static_Expression (Node (C2))
8048 Expr_Value (Node (C1)) = Expr_Value (Node (C2)))
8053 if Constraint_Present then
8055 ("constraint not conformant to previous declaration",
8059 ("constraint of full view is incompatible "
8060 & "with partial view", N);
8070 -- Insert and analyze the declaration for the unconstrained base type
8072 New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B');
8075 Make_Full_Type_Declaration (Loc,
8076 Defining_Identifier => New_Base,
8078 Make_Derived_Type_Definition (Loc,
8079 Abstract_Present => Abstract_Present (Type_Def),
8080 Limited_Present => Limited_Present (Type_Def),
8081 Subtype_Indication =>
8082 New_Occurrence_Of (Parent_Base, Loc),
8083 Record_Extension_Part =>
8084 Relocate_Node (Record_Extension_Part (Type_Def)),
8085 Interface_List => Interface_List (Type_Def)));
8087 Set_Parent (New_Decl, Parent (N));
8088 Mark_Rewrite_Insertion (New_Decl);
8089 Insert_Before (N, New_Decl);
8091 -- In the extension case, make sure ancestor is frozen appropriately
8092 -- (see also non-discriminated case below).
8094 if Present (Record_Extension_Part (Type_Def))
8095 or else Is_Interface (Parent_Base)
8097 Freeze_Before (New_Decl, Parent_Type);
8100 -- Note that this call passes False for the Derive_Subps parameter
8101 -- because subprogram derivation is deferred until after creating
8102 -- the subtype (see below).
8105 (New_Decl, Parent_Base, New_Base,
8106 Is_Completion => False, Derive_Subps => False);
8108 -- ??? This needs re-examination to determine whether the
8109 -- above call can simply be replaced by a call to Analyze.
8111 Set_Analyzed (New_Decl);
8113 -- Insert and analyze the declaration for the constrained subtype
8115 if Constraint_Present then
8117 Make_Subtype_Indication (Loc,
8118 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8119 Constraint => Relocate_Node (Constraint (Indic)));
8123 Constr_List : constant List_Id := New_List;
8128 C := First_Elmt (Discriminant_Constraint (Parent_Type));
8129 while Present (C) loop
8132 -- It is safe here to call New_Copy_Tree since we called
8133 -- Force_Evaluation on each constraint previously
8134 -- in Build_Discriminant_Constraints.
8136 Append (New_Copy_Tree (Expr), To => Constr_List);
8142 Make_Subtype_Indication (Loc,
8143 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8145 Make_Index_Or_Discriminant_Constraint (Loc, Constr_List));
8150 Make_Subtype_Declaration (Loc,
8151 Defining_Identifier => Derived_Type,
8152 Subtype_Indication => New_Indic));
8156 -- Derivation of subprograms must be delayed until the full subtype
8157 -- has been established, to ensure proper overriding of subprograms
8158 -- inherited by full types. If the derivations occurred as part of
8159 -- the call to Build_Derived_Type above, then the check for type
8160 -- conformance would fail because earlier primitive subprograms
8161 -- could still refer to the full type prior the change to the new
8162 -- subtype and hence would not match the new base type created here.
8163 -- Subprograms are not derived, however, when Derive_Subps is False
8164 -- (since otherwise there could be redundant derivations).
8166 if Derive_Subps then
8167 Derive_Subprograms (Parent_Type, Derived_Type);
8170 -- For tagged types the Discriminant_Constraint of the new base itype
8171 -- is inherited from the first subtype so that no subtype conformance
8172 -- problem arise when the first subtype overrides primitive
8173 -- operations inherited by the implicit base type.
8176 Set_Discriminant_Constraint
8177 (New_Base, Discriminant_Constraint (Derived_Type));
8183 -- If we get here Derived_Type will have no discriminants or it will be
8184 -- a discriminated unconstrained base type.
8186 -- STEP 1a: perform preliminary actions/checks for derived tagged types
8190 -- The parent type is frozen for non-private extensions (RM 13.14(7))
8191 -- The declaration of a specific descendant of an interface type
8192 -- freezes the interface type (RM 13.14).
8194 if not Private_Extension or else Is_Interface (Parent_Base) then
8195 Freeze_Before (N, Parent_Type);
8198 -- In Ada 2005 (AI-344), the restriction that a derived tagged type
8199 -- cannot be declared at a deeper level than its parent type is
8200 -- removed. The check on derivation within a generic body is also
8201 -- relaxed, but there's a restriction that a derived tagged type
8202 -- cannot be declared in a generic body if it's derived directly
8203 -- or indirectly from a formal type of that generic.
8205 if Ada_Version >= Ada_2005 then
8206 if Present (Enclosing_Generic_Body (Derived_Type)) then
8208 Ancestor_Type : Entity_Id;
8211 -- Check to see if any ancestor of the derived type is a
8214 Ancestor_Type := Parent_Type;
8215 while not Is_Generic_Type (Ancestor_Type)
8216 and then Etype (Ancestor_Type) /= Ancestor_Type
8218 Ancestor_Type := Etype (Ancestor_Type);
8221 -- If the derived type does have a formal type as an
8222 -- ancestor, then it's an error if the derived type is
8223 -- declared within the body of the generic unit that
8224 -- declares the formal type in its generic formal part. It's
8225 -- sufficient to check whether the ancestor type is declared
8226 -- inside the same generic body as the derived type (such as
8227 -- within a nested generic spec), in which case the
8228 -- derivation is legal. If the formal type is declared
8229 -- outside of that generic body, then it's guaranteed that
8230 -- the derived type is declared within the generic body of
8231 -- the generic unit declaring the formal type.
8233 if Is_Generic_Type (Ancestor_Type)
8234 and then Enclosing_Generic_Body (Ancestor_Type) /=
8235 Enclosing_Generic_Body (Derived_Type)
8238 ("parent type of& must not be descendant of formal type"
8239 & " of an enclosing generic body",
8240 Indic, Derived_Type);
8245 elsif Type_Access_Level (Derived_Type) /=
8246 Type_Access_Level (Parent_Type)
8247 and then not Is_Generic_Type (Derived_Type)
8249 if Is_Controlled (Parent_Type) then
8251 ("controlled type must be declared at the library level",
8255 ("type extension at deeper accessibility level than parent",
8261 GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type);
8264 and then GB /= Enclosing_Generic_Body (Parent_Base)
8267 ("parent type of& must not be outside generic body"
8269 Indic, Derived_Type);
8275 -- Ada 2005 (AI-251)
8277 if Ada_Version >= Ada_2005 and then Is_Tagged then
8279 -- "The declaration of a specific descendant of an interface type
8280 -- freezes the interface type" (RM 13.14).
8285 if Is_Non_Empty_List (Interface_List (Type_Def)) then
8286 Iface := First (Interface_List (Type_Def));
8287 while Present (Iface) loop
8288 Freeze_Before (N, Etype (Iface));
8295 -- STEP 1b : preliminary cleanup of the full view of private types
8297 -- If the type is already marked as having discriminants, then it's the
8298 -- completion of a private type or private extension and we need to
8299 -- retain the discriminants from the partial view if the current
8300 -- declaration has Discriminant_Specifications so that we can verify
8301 -- conformance. However, we must remove any existing components that
8302 -- were inherited from the parent (and attached in Copy_And_Swap)
8303 -- because the full type inherits all appropriate components anyway, and
8304 -- we do not want the partial view's components interfering.
8306 if Has_Discriminants (Derived_Type) and then Discriminant_Specs then
8307 Discrim := First_Discriminant (Derived_Type);
8309 Last_Discrim := Discrim;
8310 Next_Discriminant (Discrim);
8311 exit when No (Discrim);
8314 Set_Last_Entity (Derived_Type, Last_Discrim);
8316 -- In all other cases wipe out the list of inherited components (even
8317 -- inherited discriminants), it will be properly rebuilt here.
8320 Set_First_Entity (Derived_Type, Empty);
8321 Set_Last_Entity (Derived_Type, Empty);
8324 -- STEP 1c: Initialize some flags for the Derived_Type
8326 -- The following flags must be initialized here so that
8327 -- Process_Discriminants can check that discriminants of tagged types do
8328 -- not have a default initial value and that access discriminants are
8329 -- only specified for limited records. For completeness, these flags are
8330 -- also initialized along with all the other flags below.
8332 -- AI-419: Limitedness is not inherited from an interface parent, so to
8333 -- be limited in that case the type must be explicitly declared as
8334 -- limited. However, task and protected interfaces are always limited.
8336 if Limited_Present (Type_Def) then
8337 Set_Is_Limited_Record (Derived_Type);
8339 elsif Is_Limited_Record (Parent_Type)
8340 or else (Present (Full_View (Parent_Type))
8341 and then Is_Limited_Record (Full_View (Parent_Type)))
8343 if not Is_Interface (Parent_Type)
8344 or else Is_Synchronized_Interface (Parent_Type)
8345 or else Is_Protected_Interface (Parent_Type)
8346 or else Is_Task_Interface (Parent_Type)
8348 Set_Is_Limited_Record (Derived_Type);
8352 -- STEP 2a: process discriminants of derived type if any
8354 Push_Scope (Derived_Type);
8356 if Discriminant_Specs then
8357 Set_Has_Unknown_Discriminants (Derived_Type, False);
8359 -- The following call initializes fields Has_Discriminants and
8360 -- Discriminant_Constraint, unless we are processing the completion
8361 -- of a private type declaration.
8363 Check_Or_Process_Discriminants (N, Derived_Type);
8365 -- For untagged types, the constraint on the Parent_Type must be
8366 -- present and is used to rename the discriminants.
8368 if not Is_Tagged and then not Has_Discriminants (Parent_Type) then
8369 Error_Msg_N ("untagged parent must have discriminants", Indic);
8371 elsif not Is_Tagged and then not Constraint_Present then
8373 ("discriminant constraint needed for derived untagged records",
8376 -- Otherwise the parent subtype must be constrained unless we have a
8377 -- private extension.
8379 elsif not Constraint_Present
8380 and then not Private_Extension
8381 and then not Is_Constrained (Parent_Type)
8384 ("unconstrained type not allowed in this context", Indic);
8386 elsif Constraint_Present then
8387 -- The following call sets the field Corresponding_Discriminant
8388 -- for the discriminants in the Derived_Type.
8390 Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True);
8392 -- For untagged types all new discriminants must rename
8393 -- discriminants in the parent. For private extensions new
8394 -- discriminants cannot rename old ones (implied by [7.3(13)]).
8396 Discrim := First_Discriminant (Derived_Type);
8397 while Present (Discrim) loop
8399 and then No (Corresponding_Discriminant (Discrim))
8402 ("new discriminants must constrain old ones", Discrim);
8404 elsif Private_Extension
8405 and then Present (Corresponding_Discriminant (Discrim))
8408 ("only static constraints allowed for parent"
8409 & " discriminants in the partial view", Indic);
8413 -- If a new discriminant is used in the constraint, then its
8414 -- subtype must be statically compatible with the parent
8415 -- discriminant's subtype (3.7(15)).
8417 -- However, if the record contains an array constrained by
8418 -- the discriminant but with some different bound, the compiler
8419 -- attemps to create a smaller range for the discriminant type.
8420 -- (See exp_ch3.Adjust_Discriminants). In this case, where
8421 -- the discriminant type is a scalar type, the check must use
8422 -- the original discriminant type in the parent declaration.
8425 Corr_Disc : constant Entity_Id :=
8426 Corresponding_Discriminant (Discrim);
8427 Disc_Type : constant Entity_Id := Etype (Discrim);
8428 Corr_Type : Entity_Id;
8431 if Present (Corr_Disc) then
8432 if Is_Scalar_Type (Disc_Type) then
8434 Entity (Discriminant_Type (Parent (Corr_Disc)));
8436 Corr_Type := Etype (Corr_Disc);
8440 Subtypes_Statically_Compatible (Disc_Type, Corr_Type)
8443 ("subtype must be compatible "
8444 & "with parent discriminant",
8450 Next_Discriminant (Discrim);
8453 -- Check whether the constraints of the full view statically
8454 -- match those imposed by the parent subtype [7.3(13)].
8456 if Present (Stored_Constraint (Derived_Type)) then
8461 C1 := First_Elmt (Discs);
8462 C2 := First_Elmt (Stored_Constraint (Derived_Type));
8463 while Present (C1) and then Present (C2) loop
8465 Fully_Conformant_Expressions (Node (C1), Node (C2))
8468 ("not conformant with previous declaration",
8479 -- STEP 2b: No new discriminants, inherit discriminants if any
8482 if Private_Extension then
8483 Set_Has_Unknown_Discriminants
8485 Has_Unknown_Discriminants (Parent_Type)
8486 or else Unknown_Discriminants_Present (N));
8488 -- The partial view of the parent may have unknown discriminants,
8489 -- but if the full view has discriminants and the parent type is
8490 -- in scope they must be inherited.
8492 elsif Has_Unknown_Discriminants (Parent_Type)
8494 (not Has_Discriminants (Parent_Type)
8495 or else not In_Open_Scopes (Scope (Parent_Type)))
8497 Set_Has_Unknown_Discriminants (Derived_Type);
8500 if not Has_Unknown_Discriminants (Derived_Type)
8501 and then not Has_Unknown_Discriminants (Parent_Base)
8502 and then Has_Discriminants (Parent_Type)
8504 Inherit_Discrims := True;
8505 Set_Has_Discriminants
8506 (Derived_Type, True);
8507 Set_Discriminant_Constraint
8508 (Derived_Type, Discriminant_Constraint (Parent_Base));
8511 -- The following test is true for private types (remember
8512 -- transformation 5. is not applied to those) and in an error
8515 if Constraint_Present then
8516 Discs := Build_Discriminant_Constraints (Parent_Type, Indic);
8519 -- For now mark a new derived type as constrained only if it has no
8520 -- discriminants. At the end of Build_Derived_Record_Type we properly
8521 -- set this flag in the case of private extensions. See comments in
8522 -- point 9. just before body of Build_Derived_Record_Type.
8526 not (Inherit_Discrims
8527 or else Has_Unknown_Discriminants (Derived_Type)));
8530 -- STEP 3: initialize fields of derived type
8532 Set_Is_Tagged_Type (Derived_Type, Is_Tagged);
8533 Set_Stored_Constraint (Derived_Type, No_Elist);
8535 -- Ada 2005 (AI-251): Private type-declarations can implement interfaces
8536 -- but cannot be interfaces
8538 if not Private_Extension
8539 and then Ekind (Derived_Type) /= E_Private_Type
8540 and then Ekind (Derived_Type) /= E_Limited_Private_Type
8542 if Interface_Present (Type_Def) then
8543 Analyze_Interface_Declaration (Derived_Type, Type_Def);
8546 Set_Interfaces (Derived_Type, No_Elist);
8549 -- Fields inherited from the Parent_Type
8551 Set_Has_Specified_Layout
8552 (Derived_Type, Has_Specified_Layout (Parent_Type));
8553 Set_Is_Limited_Composite
8554 (Derived_Type, Is_Limited_Composite (Parent_Type));
8555 Set_Is_Private_Composite
8556 (Derived_Type, Is_Private_Composite (Parent_Type));
8558 if Is_Tagged_Type (Parent_Type) then
8559 Set_No_Tagged_Streams_Pragma
8560 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
8563 -- Fields inherited from the Parent_Base
8565 Set_Has_Controlled_Component
8566 (Derived_Type, Has_Controlled_Component (Parent_Base));
8567 Set_Has_Non_Standard_Rep
8568 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8569 Set_Has_Primitive_Operations
8570 (Derived_Type, Has_Primitive_Operations (Parent_Base));
8572 -- Fields inherited from the Parent_Base in the non-private case
8574 if Ekind (Derived_Type) = E_Record_Type then
8575 Set_Has_Complex_Representation
8576 (Derived_Type, Has_Complex_Representation (Parent_Base));
8579 -- Fields inherited from the Parent_Base for record types
8581 if Is_Record_Type (Derived_Type) then
8583 Parent_Full : Entity_Id;
8586 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
8587 -- Parent_Base can be a private type or private extension. Go
8588 -- to the full view here to get the E_Record_Type specific flags.
8590 if Present (Full_View (Parent_Base)) then
8591 Parent_Full := Full_View (Parent_Base);
8593 Parent_Full := Parent_Base;
8596 Set_OK_To_Reorder_Components
8597 (Derived_Type, OK_To_Reorder_Components (Parent_Full));
8601 -- Set fields for private derived types
8603 if Is_Private_Type (Derived_Type) then
8604 Set_Depends_On_Private (Derived_Type, True);
8605 Set_Private_Dependents (Derived_Type, New_Elmt_List);
8607 -- Inherit fields from non private record types. If this is the
8608 -- completion of a derivation from a private type, the parent itself
8609 -- is private, and the attributes come from its full view, which must
8613 if Is_Private_Type (Parent_Base)
8614 and then not Is_Record_Type (Parent_Base)
8616 Set_Component_Alignment
8617 (Derived_Type, Component_Alignment (Full_View (Parent_Base)));
8619 (Derived_Type, C_Pass_By_Copy (Full_View (Parent_Base)));
8621 Set_Component_Alignment
8622 (Derived_Type, Component_Alignment (Parent_Base));
8624 (Derived_Type, C_Pass_By_Copy (Parent_Base));
8628 -- Set fields for tagged types
8631 Set_Direct_Primitive_Operations (Derived_Type, New_Elmt_List);
8633 -- All tagged types defined in Ada.Finalization are controlled
8635 if Chars (Scope (Derived_Type)) = Name_Finalization
8636 and then Chars (Scope (Scope (Derived_Type))) = Name_Ada
8637 and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard
8639 Set_Is_Controlled (Derived_Type);
8641 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Base));
8644 -- Minor optimization: there is no need to generate the class-wide
8645 -- entity associated with an underlying record view.
8647 if not Is_Underlying_Record_View (Derived_Type) then
8648 Make_Class_Wide_Type (Derived_Type);
8651 Set_Is_Abstract_Type (Derived_Type, Abstract_Present (Type_Def));
8653 if Has_Discriminants (Derived_Type)
8654 and then Constraint_Present
8656 Set_Stored_Constraint
8657 (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs));
8660 if Ada_Version >= Ada_2005 then
8662 Ifaces_List : Elist_Id;
8665 -- Checks rules 3.9.4 (13/2 and 14/2)
8667 if Comes_From_Source (Derived_Type)
8668 and then not Is_Private_Type (Derived_Type)
8669 and then Is_Interface (Parent_Type)
8670 and then not Is_Interface (Derived_Type)
8672 if Is_Task_Interface (Parent_Type) then
8674 ("(Ada 2005) task type required (RM 3.9.4 (13.2))",
8677 elsif Is_Protected_Interface (Parent_Type) then
8679 ("(Ada 2005) protected type required (RM 3.9.4 (14.2))",
8684 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
8686 Check_Interfaces (N, Type_Def);
8688 -- Ada 2005 (AI-251): Collect the list of progenitors that are
8689 -- not already in the parents.
8693 Ifaces_List => Ifaces_List,
8694 Exclude_Parents => True);
8696 Set_Interfaces (Derived_Type, Ifaces_List);
8698 -- If the derived type is the anonymous type created for
8699 -- a declaration whose parent has a constraint, propagate
8700 -- the interface list to the source type. This must be done
8701 -- prior to the completion of the analysis of the source type
8702 -- because the components in the extension may contain current
8703 -- instances whose legality depends on some ancestor.
8705 if Is_Itype (Derived_Type) then
8707 Def : constant Node_Id :=
8708 Associated_Node_For_Itype (Derived_Type);
8711 and then Nkind (Def) = N_Full_Type_Declaration
8714 (Defining_Identifier (Def), Ifaces_List);
8719 -- Propagate inherited invariant information of parents
8722 if Ada_Version >= Ada_2012
8723 and then not Is_Interface (Derived_Type)
8725 if Has_Inheritable_Invariants (Parent_Type) then
8726 Set_Has_Invariants (Derived_Type);
8727 Set_Has_Inheritable_Invariants (Derived_Type);
8729 elsif not Is_Empty_Elmt_List (Ifaces_List) then
8734 AI := First_Elmt (Ifaces_List);
8735 while Present (AI) loop
8736 if Has_Inheritable_Invariants (Node (AI)) then
8737 Set_Has_Invariants (Derived_Type);
8738 Set_Has_Inheritable_Invariants (Derived_Type);
8749 -- A type extension is automatically Ghost when one of its
8750 -- progenitors is Ghost (SPARK RM 6.9(9)). This property is
8751 -- also inherited when the parent type is Ghost, but this is
8752 -- done in Build_Derived_Type as the mechanism also handles
8753 -- untagged derivations.
8755 if Implements_Ghost_Interface (Derived_Type) then
8756 Set_Is_Ghost_Entity (Derived_Type);
8762 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Base));
8763 Set_Has_Non_Standard_Rep
8764 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8767 -- STEP 4: Inherit components from the parent base and constrain them.
8768 -- Apply the second transformation described in point 6. above.
8770 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
8771 or else not Has_Discriminants (Parent_Type)
8772 or else not Is_Constrained (Parent_Type)
8776 Constrs := Discriminant_Constraint (Parent_Type);
8781 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
8783 -- STEP 5a: Copy the parent record declaration for untagged types
8785 if not Is_Tagged then
8787 -- Discriminant_Constraint (Derived_Type) has been properly
8788 -- constructed. Save it and temporarily set it to Empty because we
8789 -- do not want the call to New_Copy_Tree below to mess this list.
8791 if Has_Discriminants (Derived_Type) then
8792 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
8793 Set_Discriminant_Constraint (Derived_Type, No_Elist);
8795 Save_Discr_Constr := No_Elist;
8798 -- Save the Etype field of Derived_Type. It is correctly set now,
8799 -- but the call to New_Copy tree may remap it to point to itself,
8800 -- which is not what we want. Ditto for the Next_Entity field.
8802 Save_Etype := Etype (Derived_Type);
8803 Save_Next_Entity := Next_Entity (Derived_Type);
8805 -- Assoc_List maps all stored discriminants in the Parent_Base to
8806 -- stored discriminants in the Derived_Type. It is fundamental that
8807 -- no types or itypes with discriminants other than the stored
8808 -- discriminants appear in the entities declared inside
8809 -- Derived_Type, since the back end cannot deal with it.
8813 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
8815 -- Restore the fields saved prior to the New_Copy_Tree call
8816 -- and compute the stored constraint.
8818 Set_Etype (Derived_Type, Save_Etype);
8819 Set_Next_Entity (Derived_Type, Save_Next_Entity);
8821 if Has_Discriminants (Derived_Type) then
8822 Set_Discriminant_Constraint
8823 (Derived_Type, Save_Discr_Constr);
8824 Set_Stored_Constraint
8825 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
8826 Replace_Components (Derived_Type, New_Decl);
8827 Set_Has_Implicit_Dereference
8828 (Derived_Type, Has_Implicit_Dereference (Parent_Type));
8831 -- Insert the new derived type declaration
8833 Rewrite (N, New_Decl);
8835 -- STEP 5b: Complete the processing for record extensions in generics
8837 -- There is no completion for record extensions declared in the
8838 -- parameter part of a generic, so we need to complete processing for
8839 -- these generic record extensions here. The Record_Type_Definition call
8840 -- will change the Ekind of the components from E_Void to E_Component.
8842 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
8843 Record_Type_Definition (Empty, Derived_Type);
8845 -- STEP 5c: Process the record extension for non private tagged types
8847 elsif not Private_Extension then
8848 Expand_Record_Extension (Derived_Type, Type_Def);
8850 -- Note : previously in ASIS mode we set the Parent_Subtype of the
8851 -- derived type to propagate some semantic information. This led
8852 -- to other ASIS failures and has been removed.
8854 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
8855 -- implemented interfaces if we are in expansion mode
8858 and then Has_Interfaces (Derived_Type)
8860 Add_Interface_Tag_Components (N, Derived_Type);
8863 -- Analyze the record extension
8865 Record_Type_Definition
8866 (Record_Extension_Part (Type_Def), Derived_Type);
8871 -- Nothing else to do if there is an error in the derivation.
8872 -- An unusual case: the full view may be derived from a type in an
8873 -- instance, when the partial view was used illegally as an actual
8874 -- in that instance, leading to a circular definition.
8876 if Etype (Derived_Type) = Any_Type
8877 or else Etype (Parent_Type) = Derived_Type
8882 -- Set delayed freeze and then derive subprograms, we need to do
8883 -- this in this order so that derived subprograms inherit the
8884 -- derived freeze if necessary.
8886 Set_Has_Delayed_Freeze (Derived_Type);
8888 if Derive_Subps then
8889 Derive_Subprograms (Parent_Type, Derived_Type);
8892 -- If we have a private extension which defines a constrained derived
8893 -- type mark as constrained here after we have derived subprograms. See
8894 -- comment on point 9. just above the body of Build_Derived_Record_Type.
8896 if Private_Extension and then Inherit_Discrims then
8897 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
8898 Set_Is_Constrained (Derived_Type, True);
8899 Set_Discriminant_Constraint (Derived_Type, Discs);
8901 elsif Is_Constrained (Parent_Type) then
8903 (Derived_Type, True);
8904 Set_Discriminant_Constraint
8905 (Derived_Type, Discriminant_Constraint (Parent_Type));
8909 -- Update the class-wide type, which shares the now-completed entity
8910 -- list with its specific type. In case of underlying record views,
8911 -- we do not generate the corresponding class wide entity.
8914 and then not Is_Underlying_Record_View (Derived_Type)
8917 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
8919 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
8922 Check_Function_Writable_Actuals (N);
8923 end Build_Derived_Record_Type;
8925 ------------------------
8926 -- Build_Derived_Type --
8927 ------------------------
8929 procedure Build_Derived_Type
8931 Parent_Type : Entity_Id;
8932 Derived_Type : Entity_Id;
8933 Is_Completion : Boolean;
8934 Derive_Subps : Boolean := True)
8936 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
8939 -- Set common attributes
8941 Set_Scope (Derived_Type, Current_Scope);
8943 Set_Etype (Derived_Type, Parent_Base);
8944 Set_Ekind (Derived_Type, Ekind (Parent_Base));
8945 Set_Has_Task (Derived_Type, Has_Task (Parent_Base));
8946 Set_Has_Protected (Derived_Type, Has_Protected (Parent_Base));
8948 Set_Size_Info (Derived_Type, Parent_Type);
8949 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
8950 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
8951 Set_Disable_Controlled (Derived_Type, Disable_Controlled (Parent_Type));
8953 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
8954 Set_Is_Volatile (Derived_Type, Is_Volatile (Parent_Type));
8956 if Is_Tagged_Type (Derived_Type) then
8957 Set_No_Tagged_Streams_Pragma
8958 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
8961 -- If the parent has primitive routines, set the derived type link
8963 if Has_Primitive_Operations (Parent_Type) then
8964 Set_Derived_Type_Link (Parent_Base, Derived_Type);
8967 -- If the parent type is a private subtype, the convention on the base
8968 -- type may be set in the private part, and not propagated to the
8969 -- subtype until later, so we obtain the convention from the base type.
8971 Set_Convention (Derived_Type, Convention (Parent_Base));
8973 -- Set SSO default for record or array type
8975 if (Is_Array_Type (Derived_Type) or else Is_Record_Type (Derived_Type))
8976 and then Is_Base_Type (Derived_Type)
8978 Set_Default_SSO (Derived_Type);
8981 -- Propagate invariant information. The new type has invariants if
8982 -- they are inherited from the parent type, and these invariants can
8983 -- be further inherited, so both flags are set.
8985 -- We similarly inherit predicates
8987 if Has_Predicates (Parent_Type) then
8988 Set_Has_Predicates (Derived_Type);
8991 -- The derived type inherits the representation clauses of the parent
8993 Inherit_Rep_Item_Chain (Derived_Type, Parent_Type);
8995 -- Propagate the attributes related to pragma Default_Initial_Condition
8996 -- from the parent type to the private extension. A derived type always
8997 -- inherits the default initial condition flag from the parent type. If
8998 -- the derived type carries its own Default_Initial_Condition pragma,
8999 -- the flag is later reset in Analyze_Pragma. Note that both flags are
9000 -- mutually exclusive.
9002 Propagate_Default_Init_Cond_Attributes
9003 (From_Typ => Parent_Type,
9004 To_Typ => Derived_Type,
9005 Parent_To_Derivation => True);
9007 -- If the parent type has delayed rep aspects, then mark the derived
9008 -- type as possibly inheriting a delayed rep aspect.
9010 if Has_Delayed_Rep_Aspects (Parent_Type) then
9011 Set_May_Inherit_Delayed_Rep_Aspects (Derived_Type);
9014 -- Propagate the attributes related to pragma Ghost from the parent type
9015 -- to the derived type or type extension (SPARK RM 6.9(9)).
9017 if Is_Ghost_Entity (Parent_Type) then
9018 Set_Is_Ghost_Entity (Derived_Type);
9021 -- Type dependent processing
9023 case Ekind (Parent_Type) is
9024 when Numeric_Kind =>
9025 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
9028 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
9032 | Class_Wide_Kind =>
9033 Build_Derived_Record_Type
9034 (N, Parent_Type, Derived_Type, Derive_Subps);
9037 when Enumeration_Kind =>
9038 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
9041 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
9043 when Incomplete_Or_Private_Kind =>
9044 Build_Derived_Private_Type
9045 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
9047 -- For discriminated types, the derivation includes deriving
9048 -- primitive operations. For others it is done below.
9050 if Is_Tagged_Type (Parent_Type)
9051 or else Has_Discriminants (Parent_Type)
9052 or else (Present (Full_View (Parent_Type))
9053 and then Has_Discriminants (Full_View (Parent_Type)))
9058 when Concurrent_Kind =>
9059 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
9062 raise Program_Error;
9065 -- Nothing more to do if some error occurred
9067 if Etype (Derived_Type) = Any_Type then
9071 -- Set delayed freeze and then derive subprograms, we need to do this
9072 -- in this order so that derived subprograms inherit the derived freeze
9075 Set_Has_Delayed_Freeze (Derived_Type);
9077 if Derive_Subps then
9078 Derive_Subprograms (Parent_Type, Derived_Type);
9081 Set_Has_Primitive_Operations
9082 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
9083 end Build_Derived_Type;
9085 -----------------------
9086 -- Build_Discriminal --
9087 -----------------------
9089 procedure Build_Discriminal (Discrim : Entity_Id) is
9090 D_Minal : Entity_Id;
9091 CR_Disc : Entity_Id;
9094 -- A discriminal has the same name as the discriminant
9096 D_Minal := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
9098 Set_Ekind (D_Minal, E_In_Parameter);
9099 Set_Mechanism (D_Minal, Default_Mechanism);
9100 Set_Etype (D_Minal, Etype (Discrim));
9101 Set_Scope (D_Minal, Current_Scope);
9103 Set_Discriminal (Discrim, D_Minal);
9104 Set_Discriminal_Link (D_Minal, Discrim);
9106 -- For task types, build at once the discriminants of the corresponding
9107 -- record, which are needed if discriminants are used in entry defaults
9108 -- and in family bounds.
9110 if Is_Concurrent_Type (Current_Scope)
9112 Is_Limited_Type (Current_Scope)
9114 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
9116 Set_Ekind (CR_Disc, E_In_Parameter);
9117 Set_Mechanism (CR_Disc, Default_Mechanism);
9118 Set_Etype (CR_Disc, Etype (Discrim));
9119 Set_Scope (CR_Disc, Current_Scope);
9120 Set_Discriminal_Link (CR_Disc, Discrim);
9121 Set_CR_Discriminant (Discrim, CR_Disc);
9123 end Build_Discriminal;
9125 ------------------------------------
9126 -- Build_Discriminant_Constraints --
9127 ------------------------------------
9129 function Build_Discriminant_Constraints
9132 Derived_Def : Boolean := False) return Elist_Id
9134 C : constant Node_Id := Constraint (Def);
9135 Nb_Discr : constant Nat := Number_Discriminants (T);
9137 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
9138 -- Saves the expression corresponding to a given discriminant in T
9140 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
9141 -- Return the Position number within array Discr_Expr of a discriminant
9142 -- D within the discriminant list of the discriminated type T.
9144 procedure Process_Discriminant_Expression
9147 -- If this is a discriminant constraint on a partial view, do not
9148 -- generate an overflow check on the discriminant expression. The check
9149 -- will be generated when constraining the full view. Otherwise the
9150 -- backend creates duplicate symbols for the temporaries corresponding
9151 -- to the expressions to be checked, causing spurious assembler errors.
9157 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
9161 Disc := First_Discriminant (T);
9162 for J in Discr_Expr'Range loop
9167 Next_Discriminant (Disc);
9170 -- Note: Since this function is called on discriminants that are
9171 -- known to belong to the discriminated type, falling through the
9172 -- loop with no match signals an internal compiler error.
9174 raise Program_Error;
9177 -------------------------------------
9178 -- Process_Discriminant_Expression --
9179 -------------------------------------
9181 procedure Process_Discriminant_Expression
9185 BDT : constant Entity_Id := Base_Type (Etype (D));
9188 -- If this is a discriminant constraint on a partial view, do
9189 -- not generate an overflow on the discriminant expression. The
9190 -- check will be generated when constraining the full view.
9192 if Is_Private_Type (T)
9193 and then Present (Full_View (T))
9195 Analyze_And_Resolve (Expr, BDT, Suppress => Overflow_Check);
9197 Analyze_And_Resolve (Expr, BDT);
9199 end Process_Discriminant_Expression;
9201 -- Declarations local to Build_Discriminant_Constraints
9205 Elist : constant Elist_Id := New_Elmt_List;
9213 Discrim_Present : Boolean := False;
9215 -- Start of processing for Build_Discriminant_Constraints
9218 -- The following loop will process positional associations only.
9219 -- For a positional association, the (single) discriminant is
9220 -- implicitly specified by position, in textual order (RM 3.7.2).
9222 Discr := First_Discriminant (T);
9223 Constr := First (Constraints (C));
9224 for D in Discr_Expr'Range loop
9225 exit when Nkind (Constr) = N_Discriminant_Association;
9228 Error_Msg_N ("too few discriminants given in constraint", C);
9229 return New_Elmt_List;
9231 elsif Nkind (Constr) = N_Range
9232 or else (Nkind (Constr) = N_Attribute_Reference
9233 and then Attribute_Name (Constr) = Name_Range)
9236 ("a range is not a valid discriminant constraint", Constr);
9237 Discr_Expr (D) := Error;
9240 Process_Discriminant_Expression (Constr, Discr);
9241 Discr_Expr (D) := Constr;
9244 Next_Discriminant (Discr);
9248 if No (Discr) and then Present (Constr) then
9249 Error_Msg_N ("too many discriminants given in constraint", Constr);
9250 return New_Elmt_List;
9253 -- Named associations can be given in any order, but if both positional
9254 -- and named associations are used in the same discriminant constraint,
9255 -- then positional associations must occur first, at their normal
9256 -- position. Hence once a named association is used, the rest of the
9257 -- discriminant constraint must use only named associations.
9259 while Present (Constr) loop
9261 -- Positional association forbidden after a named association
9263 if Nkind (Constr) /= N_Discriminant_Association then
9264 Error_Msg_N ("positional association follows named one", Constr);
9265 return New_Elmt_List;
9267 -- Otherwise it is a named association
9270 -- E records the type of the discriminants in the named
9271 -- association. All the discriminants specified in the same name
9272 -- association must have the same type.
9276 -- Search the list of discriminants in T to see if the simple name
9277 -- given in the constraint matches any of them.
9279 Id := First (Selector_Names (Constr));
9280 while Present (Id) loop
9283 -- If Original_Discriminant is present, we are processing a
9284 -- generic instantiation and this is an instance node. We need
9285 -- to find the name of the corresponding discriminant in the
9286 -- actual record type T and not the name of the discriminant in
9287 -- the generic formal. Example:
9290 -- type G (D : int) is private;
9292 -- subtype W is G (D => 1);
9294 -- type Rec (X : int) is record ... end record;
9295 -- package Q is new P (G => Rec);
9297 -- At the point of the instantiation, formal type G is Rec
9298 -- and therefore when reanalyzing "subtype W is G (D => 1);"
9299 -- which really looks like "subtype W is Rec (D => 1);" at
9300 -- the point of instantiation, we want to find the discriminant
9301 -- that corresponds to D in Rec, i.e. X.
9303 if Present (Original_Discriminant (Id))
9304 and then In_Instance
9306 Discr := Find_Corresponding_Discriminant (Id, T);
9310 Discr := First_Discriminant (T);
9311 while Present (Discr) loop
9312 if Chars (Discr) = Chars (Id) then
9317 Next_Discriminant (Discr);
9321 Error_Msg_N ("& does not match any discriminant", Id);
9322 return New_Elmt_List;
9324 -- If the parent type is a generic formal, preserve the
9325 -- name of the discriminant for subsequent instances.
9326 -- see comment at the beginning of this if statement.
9328 elsif Is_Generic_Type (Root_Type (T)) then
9329 Set_Original_Discriminant (Id, Discr);
9333 Position := Pos_Of_Discr (T, Discr);
9335 if Present (Discr_Expr (Position)) then
9336 Error_Msg_N ("duplicate constraint for discriminant&", Id);
9339 -- Each discriminant specified in the same named association
9340 -- must be associated with a separate copy of the
9341 -- corresponding expression.
9343 if Present (Next (Id)) then
9344 Expr := New_Copy_Tree (Expression (Constr));
9345 Set_Parent (Expr, Parent (Expression (Constr)));
9347 Expr := Expression (Constr);
9350 Discr_Expr (Position) := Expr;
9351 Process_Discriminant_Expression (Expr, Discr);
9354 -- A discriminant association with more than one discriminant
9355 -- name is only allowed if the named discriminants are all of
9356 -- the same type (RM 3.7.1(8)).
9359 E := Base_Type (Etype (Discr));
9361 elsif Base_Type (Etype (Discr)) /= E then
9363 ("all discriminants in an association " &
9364 "must have the same type", Id);
9374 -- A discriminant constraint must provide exactly one value for each
9375 -- discriminant of the type (RM 3.7.1(8)).
9377 for J in Discr_Expr'Range loop
9378 if No (Discr_Expr (J)) then
9379 Error_Msg_N ("too few discriminants given in constraint", C);
9380 return New_Elmt_List;
9384 -- Determine if there are discriminant expressions in the constraint
9386 for J in Discr_Expr'Range loop
9387 if Denotes_Discriminant
9388 (Discr_Expr (J), Check_Concurrent => True)
9390 Discrim_Present := True;
9394 -- Build an element list consisting of the expressions given in the
9395 -- discriminant constraint and apply the appropriate checks. The list
9396 -- is constructed after resolving any named discriminant associations
9397 -- and therefore the expressions appear in the textual order of the
9400 Discr := First_Discriminant (T);
9401 for J in Discr_Expr'Range loop
9402 if Discr_Expr (J) /= Error then
9403 Append_Elmt (Discr_Expr (J), Elist);
9405 -- If any of the discriminant constraints is given by a
9406 -- discriminant and we are in a derived type declaration we
9407 -- have a discriminant renaming. Establish link between new
9408 -- and old discriminant.
9410 if Denotes_Discriminant (Discr_Expr (J)) then
9412 Set_Corresponding_Discriminant
9413 (Entity (Discr_Expr (J)), Discr);
9416 -- Force the evaluation of non-discriminant expressions.
9417 -- If we have found a discriminant in the constraint 3.4(26)
9418 -- and 3.8(18) demand that no range checks are performed are
9419 -- after evaluation. If the constraint is for a component
9420 -- definition that has a per-object constraint, expressions are
9421 -- evaluated but not checked either. In all other cases perform
9425 if Discrim_Present then
9428 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
9430 Has_Per_Object_Constraint
9431 (Defining_Identifier (Parent (Parent (Def))))
9435 elsif Is_Access_Type (Etype (Discr)) then
9436 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
9439 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
9442 Force_Evaluation (Discr_Expr (J));
9445 -- Check that the designated type of an access discriminant's
9446 -- expression is not a class-wide type unless the discriminant's
9447 -- designated type is also class-wide.
9449 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
9450 and then not Is_Class_Wide_Type
9451 (Designated_Type (Etype (Discr)))
9452 and then Etype (Discr_Expr (J)) /= Any_Type
9453 and then Is_Class_Wide_Type
9454 (Designated_Type (Etype (Discr_Expr (J))))
9456 Wrong_Type (Discr_Expr (J), Etype (Discr));
9458 elsif Is_Access_Type (Etype (Discr))
9459 and then not Is_Access_Constant (Etype (Discr))
9460 and then Is_Access_Type (Etype (Discr_Expr (J)))
9461 and then Is_Access_Constant (Etype (Discr_Expr (J)))
9464 ("constraint for discriminant& must be access to variable",
9469 Next_Discriminant (Discr);
9473 end Build_Discriminant_Constraints;
9475 ---------------------------------
9476 -- Build_Discriminated_Subtype --
9477 ---------------------------------
9479 procedure Build_Discriminated_Subtype
9483 Related_Nod : Node_Id;
9484 For_Access : Boolean := False)
9486 Has_Discrs : constant Boolean := Has_Discriminants (T);
9487 Constrained : constant Boolean :=
9489 and then not Is_Empty_Elmt_List (Elist)
9490 and then not Is_Class_Wide_Type (T))
9491 or else Is_Constrained (T);
9494 if Ekind (T) = E_Record_Type then
9496 Set_Ekind (Def_Id, E_Private_Subtype);
9497 Set_Is_For_Access_Subtype (Def_Id, True);
9499 Set_Ekind (Def_Id, E_Record_Subtype);
9502 -- Inherit preelaboration flag from base, for types for which it
9503 -- may have been set: records, private types, protected types.
9505 Set_Known_To_Have_Preelab_Init
9506 (Def_Id, Known_To_Have_Preelab_Init (T));
9508 elsif Ekind (T) = E_Task_Type then
9509 Set_Ekind (Def_Id, E_Task_Subtype);
9511 elsif Ekind (T) = E_Protected_Type then
9512 Set_Ekind (Def_Id, E_Protected_Subtype);
9513 Set_Known_To_Have_Preelab_Init
9514 (Def_Id, Known_To_Have_Preelab_Init (T));
9516 elsif Is_Private_Type (T) then
9517 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
9518 Set_Known_To_Have_Preelab_Init
9519 (Def_Id, Known_To_Have_Preelab_Init (T));
9521 -- Private subtypes may have private dependents
9523 Set_Private_Dependents (Def_Id, New_Elmt_List);
9525 elsif Is_Class_Wide_Type (T) then
9526 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
9529 -- Incomplete type. Attach subtype to list of dependents, to be
9530 -- completed with full view of parent type, unless is it the
9531 -- designated subtype of a record component within an init_proc.
9532 -- This last case arises for a component of an access type whose
9533 -- designated type is incomplete (e.g. a Taft Amendment type).
9534 -- The designated subtype is within an inner scope, and needs no
9535 -- elaboration, because only the access type is needed in the
9536 -- initialization procedure.
9538 Set_Ekind (Def_Id, Ekind (T));
9540 if For_Access and then Within_Init_Proc then
9543 Append_Elmt (Def_Id, Private_Dependents (T));
9547 Set_Etype (Def_Id, T);
9548 Init_Size_Align (Def_Id);
9549 Set_Has_Discriminants (Def_Id, Has_Discrs);
9550 Set_Is_Constrained (Def_Id, Constrained);
9552 Set_First_Entity (Def_Id, First_Entity (T));
9553 Set_Last_Entity (Def_Id, Last_Entity (T));
9554 Set_Has_Implicit_Dereference
9555 (Def_Id, Has_Implicit_Dereference (T));
9557 -- If the subtype is the completion of a private declaration, there may
9558 -- have been representation clauses for the partial view, and they must
9559 -- be preserved. Build_Derived_Type chains the inherited clauses with
9560 -- the ones appearing on the extension. If this comes from a subtype
9561 -- declaration, all clauses are inherited.
9563 if No (First_Rep_Item (Def_Id)) then
9564 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
9567 if Is_Tagged_Type (T) then
9568 Set_Is_Tagged_Type (Def_Id);
9569 Set_No_Tagged_Streams_Pragma (Def_Id, No_Tagged_Streams_Pragma (T));
9570 Make_Class_Wide_Type (Def_Id);
9573 Set_Stored_Constraint (Def_Id, No_Elist);
9576 Set_Discriminant_Constraint (Def_Id, Elist);
9577 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
9580 if Is_Tagged_Type (T) then
9582 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
9583 -- concurrent record type (which has the list of primitive
9586 if Ada_Version >= Ada_2005
9587 and then Is_Concurrent_Type (T)
9589 Set_Corresponding_Record_Type (Def_Id,
9590 Corresponding_Record_Type (T));
9592 Set_Direct_Primitive_Operations (Def_Id,
9593 Direct_Primitive_Operations (T));
9596 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
9599 -- Subtypes introduced by component declarations do not need to be
9600 -- marked as delayed, and do not get freeze nodes, because the semantics
9601 -- verifies that the parents of the subtypes are frozen before the
9602 -- enclosing record is frozen.
9604 if not Is_Type (Scope (Def_Id)) then
9605 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
9607 if Is_Private_Type (T)
9608 and then Present (Full_View (T))
9610 Conditional_Delay (Def_Id, Full_View (T));
9612 Conditional_Delay (Def_Id, T);
9616 if Is_Record_Type (T) then
9617 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
9620 and then not Is_Empty_Elmt_List (Elist)
9621 and then not For_Access
9623 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
9624 elsif not For_Access then
9625 Set_Cloned_Subtype (Def_Id, T);
9628 end Build_Discriminated_Subtype;
9630 ---------------------------
9631 -- Build_Itype_Reference --
9632 ---------------------------
9634 procedure Build_Itype_Reference
9638 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
9641 -- Itype references are only created for use by the back-end
9643 if Inside_A_Generic then
9646 Set_Itype (IR, Ityp);
9647 Insert_After (Nod, IR);
9649 end Build_Itype_Reference;
9651 ------------------------
9652 -- Build_Scalar_Bound --
9653 ------------------------
9655 function Build_Scalar_Bound
9658 Der_T : Entity_Id) return Node_Id
9660 New_Bound : Entity_Id;
9663 -- Note: not clear why this is needed, how can the original bound
9664 -- be unanalyzed at this point? and if it is, what business do we
9665 -- have messing around with it? and why is the base type of the
9666 -- parent type the right type for the resolution. It probably is
9667 -- not. It is OK for the new bound we are creating, but not for
9668 -- the old one??? Still if it never happens, no problem.
9670 Analyze_And_Resolve (Bound, Base_Type (Par_T));
9672 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
9673 New_Bound := New_Copy (Bound);
9674 Set_Etype (New_Bound, Der_T);
9675 Set_Analyzed (New_Bound);
9677 elsif Is_Entity_Name (Bound) then
9678 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
9680 -- The following is almost certainly wrong. What business do we have
9681 -- relocating a node (Bound) that is presumably still attached to
9682 -- the tree elsewhere???
9685 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
9688 Set_Etype (New_Bound, Der_T);
9690 end Build_Scalar_Bound;
9692 --------------------------------
9693 -- Build_Underlying_Full_View --
9694 --------------------------------
9696 procedure Build_Underlying_Full_View
9701 Loc : constant Source_Ptr := Sloc (N);
9702 Subt : constant Entity_Id :=
9703 Make_Defining_Identifier
9704 (Loc, New_External_Name (Chars (Typ), 'S'));
9711 procedure Set_Discriminant_Name (Id : Node_Id);
9712 -- If the derived type has discriminants, they may rename discriminants
9713 -- of the parent. When building the full view of the parent, we need to
9714 -- recover the names of the original discriminants if the constraint is
9715 -- given by named associations.
9717 ---------------------------
9718 -- Set_Discriminant_Name --
9719 ---------------------------
9721 procedure Set_Discriminant_Name (Id : Node_Id) is
9725 Set_Original_Discriminant (Id, Empty);
9727 if Has_Discriminants (Typ) then
9728 Disc := First_Discriminant (Typ);
9729 while Present (Disc) loop
9730 if Chars (Disc) = Chars (Id)
9731 and then Present (Corresponding_Discriminant (Disc))
9733 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
9735 Next_Discriminant (Disc);
9738 end Set_Discriminant_Name;
9740 -- Start of processing for Build_Underlying_Full_View
9743 if Nkind (N) = N_Full_Type_Declaration then
9744 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
9746 elsif Nkind (N) = N_Subtype_Declaration then
9747 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
9749 elsif Nkind (N) = N_Component_Declaration then
9752 (Constraint (Subtype_Indication (Component_Definition (N))));
9755 raise Program_Error;
9758 C := First (Constraints (Constr));
9759 while Present (C) loop
9760 if Nkind (C) = N_Discriminant_Association then
9761 Id := First (Selector_Names (C));
9762 while Present (Id) loop
9763 Set_Discriminant_Name (Id);
9772 Make_Subtype_Declaration (Loc,
9773 Defining_Identifier => Subt,
9774 Subtype_Indication =>
9775 Make_Subtype_Indication (Loc,
9776 Subtype_Mark => New_Occurrence_Of (Par, Loc),
9777 Constraint => New_Copy_Tree (Constr)));
9779 -- If this is a component subtype for an outer itype, it is not
9780 -- a list member, so simply set the parent link for analysis: if
9781 -- the enclosing type does not need to be in a declarative list,
9782 -- neither do the components.
9784 if Is_List_Member (N)
9785 and then Nkind (N) /= N_Component_Declaration
9787 Insert_Before (N, Indic);
9789 Set_Parent (Indic, Parent (N));
9793 Set_Underlying_Full_View (Typ, Full_View (Subt));
9794 end Build_Underlying_Full_View;
9796 -------------------------------
9797 -- Check_Abstract_Overriding --
9798 -------------------------------
9800 procedure Check_Abstract_Overriding (T : Entity_Id) is
9801 Alias_Subp : Entity_Id;
9807 procedure Check_Pragma_Implemented (Subp : Entity_Id);
9808 -- Ada 2012 (AI05-0030): Subprogram Subp overrides an interface routine
9809 -- which has pragma Implemented already set. Check whether Subp's entity
9810 -- kind conforms to the implementation kind of the overridden routine.
9812 procedure Check_Pragma_Implemented
9814 Iface_Subp : Entity_Id);
9815 -- Ada 2012 (AI05-0030): Subprogram Subp overrides interface routine
9816 -- Iface_Subp and both entities have pragma Implemented already set on
9817 -- them. Check whether the two implementation kinds are conforming.
9819 procedure Inherit_Pragma_Implemented
9821 Iface_Subp : Entity_Id);
9822 -- Ada 2012 (AI05-0030): Interface primitive Subp overrides interface
9823 -- subprogram Iface_Subp which has been marked by pragma Implemented.
9824 -- Propagate the implementation kind of Iface_Subp to Subp.
9826 ------------------------------
9827 -- Check_Pragma_Implemented --
9828 ------------------------------
9830 procedure Check_Pragma_Implemented (Subp : Entity_Id) is
9831 Iface_Alias : constant Entity_Id := Interface_Alias (Subp);
9832 Impl_Kind : constant Name_Id := Implementation_Kind (Iface_Alias);
9833 Subp_Alias : constant Entity_Id := Alias (Subp);
9834 Contr_Typ : Entity_Id;
9835 Impl_Subp : Entity_Id;
9838 -- Subp must have an alias since it is a hidden entity used to link
9839 -- an interface subprogram to its overriding counterpart.
9841 pragma Assert (Present (Subp_Alias));
9843 -- Handle aliases to synchronized wrappers
9845 Impl_Subp := Subp_Alias;
9847 if Is_Primitive_Wrapper (Impl_Subp) then
9848 Impl_Subp := Wrapped_Entity (Impl_Subp);
9851 -- Extract the type of the controlling formal
9853 Contr_Typ := Etype (First_Formal (Subp_Alias));
9855 if Is_Concurrent_Record_Type (Contr_Typ) then
9856 Contr_Typ := Corresponding_Concurrent_Type (Contr_Typ);
9859 -- An interface subprogram whose implementation kind is By_Entry must
9860 -- be implemented by an entry.
9862 if Impl_Kind = Name_By_Entry
9863 and then Ekind (Impl_Subp) /= E_Entry
9865 Error_Msg_Node_2 := Iface_Alias;
9867 ("type & must implement abstract subprogram & with an entry",
9868 Subp_Alias, Contr_Typ);
9870 elsif Impl_Kind = Name_By_Protected_Procedure then
9872 -- An interface subprogram whose implementation kind is By_
9873 -- Protected_Procedure cannot be implemented by a primitive
9874 -- procedure of a task type.
9876 if Ekind (Contr_Typ) /= E_Protected_Type then
9877 Error_Msg_Node_2 := Contr_Typ;
9879 ("interface subprogram & cannot be implemented by a " &
9880 "primitive procedure of task type &", Subp_Alias,
9883 -- An interface subprogram whose implementation kind is By_
9884 -- Protected_Procedure must be implemented by a procedure.
9886 elsif Ekind (Impl_Subp) /= E_Procedure then
9887 Error_Msg_Node_2 := Iface_Alias;
9889 ("type & must implement abstract subprogram & with a " &
9890 "procedure", Subp_Alias, Contr_Typ);
9892 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
9893 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
9895 Error_Msg_Name_1 := Impl_Kind;
9897 ("overriding operation& must have synchronization%",
9901 -- If primitive has Optional synchronization, overriding operation
9902 -- must match if it has an explicit synchronization..
9904 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
9905 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
9907 Error_Msg_Name_1 := Impl_Kind;
9909 ("overriding operation& must have syncrhonization%",
9912 end Check_Pragma_Implemented;
9914 ------------------------------
9915 -- Check_Pragma_Implemented --
9916 ------------------------------
9918 procedure Check_Pragma_Implemented
9920 Iface_Subp : Entity_Id)
9922 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
9923 Subp_Kind : constant Name_Id := Implementation_Kind (Subp);
9926 -- Ada 2012 (AI05-0030): The implementation kinds of an overridden
9927 -- and overriding subprogram are different. In general this is an
9928 -- error except when the implementation kind of the overridden
9929 -- subprograms is By_Any or Optional.
9931 if Iface_Kind /= Subp_Kind
9932 and then Iface_Kind /= Name_By_Any
9933 and then Iface_Kind /= Name_Optional
9935 if Iface_Kind = Name_By_Entry then
9937 ("incompatible implementation kind, overridden subprogram " &
9938 "is marked By_Entry", Subp);
9941 ("incompatible implementation kind, overridden subprogram " &
9942 "is marked By_Protected_Procedure", Subp);
9945 end Check_Pragma_Implemented;
9947 --------------------------------
9948 -- Inherit_Pragma_Implemented --
9949 --------------------------------
9951 procedure Inherit_Pragma_Implemented
9953 Iface_Subp : Entity_Id)
9955 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
9956 Loc : constant Source_Ptr := Sloc (Subp);
9957 Impl_Prag : Node_Id;
9960 -- Since the implementation kind is stored as a representation item
9961 -- rather than a flag, create a pragma node.
9965 Chars => Name_Implemented,
9966 Pragma_Argument_Associations => New_List (
9967 Make_Pragma_Argument_Association (Loc,
9968 Expression => New_Occurrence_Of (Subp, Loc)),
9970 Make_Pragma_Argument_Association (Loc,
9971 Expression => Make_Identifier (Loc, Iface_Kind))));
9973 -- The pragma doesn't need to be analyzed because it is internally
9974 -- built. It is safe to directly register it as a rep item since we
9975 -- are only interested in the characters of the implementation kind.
9977 Record_Rep_Item (Subp, Impl_Prag);
9978 end Inherit_Pragma_Implemented;
9980 -- Start of processing for Check_Abstract_Overriding
9983 Op_List := Primitive_Operations (T);
9985 -- Loop to check primitive operations
9987 Elmt := First_Elmt (Op_List);
9988 while Present (Elmt) loop
9989 Subp := Node (Elmt);
9990 Alias_Subp := Alias (Subp);
9992 -- Inherited subprograms are identified by the fact that they do not
9993 -- come from source, and the associated source location is the
9994 -- location of the first subtype of the derived type.
9996 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
9997 -- subprograms that "require overriding".
9999 -- Special exception, do not complain about failure to override the
10000 -- stream routines _Input and _Output, as well as the primitive
10001 -- operations used in dispatching selects since we always provide
10002 -- automatic overridings for these subprograms.
10004 -- The partial view of T may have been a private extension, for
10005 -- which inherited functions dispatching on result are abstract.
10006 -- If the full view is a null extension, there is no need for
10007 -- overriding in Ada 2005, but wrappers need to be built for them
10008 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
10010 if Is_Null_Extension (T)
10011 and then Has_Controlling_Result (Subp)
10012 and then Ada_Version >= Ada_2005
10013 and then Present (Alias_Subp)
10014 and then not Comes_From_Source (Subp)
10015 and then not Is_Abstract_Subprogram (Alias_Subp)
10016 and then not Is_Access_Type (Etype (Subp))
10020 -- Ada 2005 (AI-251): Internal entities of interfaces need no
10021 -- processing because this check is done with the aliased
10024 elsif Present (Interface_Alias (Subp)) then
10027 elsif (Is_Abstract_Subprogram (Subp)
10028 or else Requires_Overriding (Subp)
10030 (Has_Controlling_Result (Subp)
10031 and then Present (Alias_Subp)
10032 and then not Comes_From_Source (Subp)
10033 and then Sloc (Subp) = Sloc (First_Subtype (T))))
10034 and then not Is_TSS (Subp, TSS_Stream_Input)
10035 and then not Is_TSS (Subp, TSS_Stream_Output)
10036 and then not Is_Abstract_Type (T)
10037 and then not Is_Predefined_Interface_Primitive (Subp)
10039 -- Ada 2005 (AI-251): Do not consider hidden entities associated
10040 -- with abstract interface types because the check will be done
10041 -- with the aliased entity (otherwise we generate a duplicated
10044 and then not Present (Interface_Alias (Subp))
10046 if Present (Alias_Subp) then
10048 -- Only perform the check for a derived subprogram when the
10049 -- type has an explicit record extension. This avoids incorrect
10050 -- flagging of abstract subprograms for the case of a type
10051 -- without an extension that is derived from a formal type
10052 -- with a tagged actual (can occur within a private part).
10054 -- Ada 2005 (AI-391): In the case of an inherited function with
10055 -- a controlling result of the type, the rule does not apply if
10056 -- the type is a null extension (unless the parent function
10057 -- itself is abstract, in which case the function must still be
10058 -- be overridden). The expander will generate an overriding
10059 -- wrapper function calling the parent subprogram (see
10060 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
10062 Type_Def := Type_Definition (Parent (T));
10064 if Nkind (Type_Def) = N_Derived_Type_Definition
10065 and then Present (Record_Extension_Part (Type_Def))
10067 (Ada_Version < Ada_2005
10068 or else not Is_Null_Extension (T)
10069 or else Ekind (Subp) = E_Procedure
10070 or else not Has_Controlling_Result (Subp)
10071 or else Is_Abstract_Subprogram (Alias_Subp)
10072 or else Requires_Overriding (Subp)
10073 or else Is_Access_Type (Etype (Subp)))
10075 -- Avoid reporting error in case of abstract predefined
10076 -- primitive inherited from interface type because the
10077 -- body of internally generated predefined primitives
10078 -- of tagged types are generated later by Freeze_Type
10080 if Is_Interface (Root_Type (T))
10081 and then Is_Abstract_Subprogram (Subp)
10082 and then Is_Predefined_Dispatching_Operation (Subp)
10083 and then not Comes_From_Source (Ultimate_Alias (Subp))
10087 -- A null extension is not obliged to override an inherited
10088 -- procedure subject to pragma Extensions_Visible with value
10089 -- False and at least one controlling OUT parameter
10090 -- (SPARK RM 6.1.7(6)).
10092 elsif Is_Null_Extension (T)
10093 and then Is_EVF_Procedure (Subp)
10099 ("type must be declared abstract or & overridden",
10102 -- Traverse the whole chain of aliased subprograms to
10103 -- complete the error notification. This is especially
10104 -- useful for traceability of the chain of entities when
10105 -- the subprogram corresponds with an interface
10106 -- subprogram (which may be defined in another package).
10108 if Present (Alias_Subp) then
10114 while Present (Alias (E)) loop
10116 -- Avoid reporting redundant errors on entities
10117 -- inherited from interfaces
10119 if Sloc (E) /= Sloc (T) then
10120 Error_Msg_Sloc := Sloc (E);
10122 ("\& has been inherited #", T, Subp);
10128 Error_Msg_Sloc := Sloc (E);
10130 -- AI05-0068: report if there is an overriding
10131 -- non-abstract subprogram that is invisible.
10134 and then not Is_Abstract_Subprogram (E)
10137 ("\& subprogram# is not visible",
10140 -- Clarify the case where a non-null extension must
10141 -- override inherited procedure subject to pragma
10142 -- Extensions_Visible with value False and at least
10143 -- one controlling OUT param.
10145 elsif Is_EVF_Procedure (E) then
10147 ("\& # is subject to Extensions_Visible False",
10152 ("\& has been inherited from subprogram #",
10159 -- Ada 2005 (AI-345): Protected or task type implementing
10160 -- abstract interfaces.
10162 elsif Is_Concurrent_Record_Type (T)
10163 and then Present (Interfaces (T))
10165 -- There is no need to check here RM 9.4(11.9/3) since we
10166 -- are processing the corresponding record type and the
10167 -- mode of the overriding subprograms was verified by
10168 -- Check_Conformance when the corresponding concurrent
10169 -- type declaration was analyzed.
10172 ("interface subprogram & must be overridden", T, Subp);
10174 -- Examine primitive operations of synchronized type to find
10175 -- homonyms that have the wrong profile.
10181 Prim := First_Entity (Corresponding_Concurrent_Type (T));
10182 while Present (Prim) loop
10183 if Chars (Prim) = Chars (Subp) then
10185 ("profile is not type conformant with prefixed "
10186 & "view profile of inherited operation&",
10190 Next_Entity (Prim);
10196 Error_Msg_Node_2 := T;
10198 ("abstract subprogram& not allowed for type&", Subp);
10200 -- Also post unconditional warning on the type (unconditional
10201 -- so that if there are more than one of these cases, we get
10202 -- them all, and not just the first one).
10204 Error_Msg_Node_2 := Subp;
10205 Error_Msg_N ("nonabstract type& has abstract subprogram&!", T);
10208 -- A subprogram subject to pragma Extensions_Visible with value
10209 -- "True" cannot override a subprogram subject to the same pragma
10210 -- with value "False" (SPARK RM 6.1.7(5)).
10212 elsif Extensions_Visible_Status (Subp) = Extensions_Visible_True
10213 and then Present (Overridden_Operation (Subp))
10214 and then Extensions_Visible_Status (Overridden_Operation (Subp)) =
10215 Extensions_Visible_False
10217 Error_Msg_Sloc := Sloc (Overridden_Operation (Subp));
10219 ("subprogram & with Extensions_Visible True cannot override "
10220 & "subprogram # with Extensions_Visible False", Subp);
10223 -- Ada 2012 (AI05-0030): Perform checks related to pragma Implemented
10225 -- Subp is an expander-generated procedure which maps an interface
10226 -- alias to a protected wrapper. The interface alias is flagged by
10227 -- pragma Implemented. Ensure that Subp is a procedure when the
10228 -- implementation kind is By_Protected_Procedure or an entry when
10231 if Ada_Version >= Ada_2012
10232 and then Is_Hidden (Subp)
10233 and then Present (Interface_Alias (Subp))
10234 and then Has_Rep_Pragma (Interface_Alias (Subp), Name_Implemented)
10236 Check_Pragma_Implemented (Subp);
10239 -- Subp is an interface primitive which overrides another interface
10240 -- primitive marked with pragma Implemented.
10242 if Ada_Version >= Ada_2012
10243 and then Present (Overridden_Operation (Subp))
10244 and then Has_Rep_Pragma
10245 (Overridden_Operation (Subp), Name_Implemented)
10247 -- If the overriding routine is also marked by Implemented, check
10248 -- that the two implementation kinds are conforming.
10250 if Has_Rep_Pragma (Subp, Name_Implemented) then
10251 Check_Pragma_Implemented
10253 Iface_Subp => Overridden_Operation (Subp));
10255 -- Otherwise the overriding routine inherits the implementation
10256 -- kind from the overridden subprogram.
10259 Inherit_Pragma_Implemented
10261 Iface_Subp => Overridden_Operation (Subp));
10265 -- If the operation is a wrapper for a synchronized primitive, it
10266 -- may be called indirectly through a dispatching select. We assume
10267 -- that it will be referenced elsewhere indirectly, and suppress
10268 -- warnings about an unused entity.
10270 if Is_Primitive_Wrapper (Subp)
10271 and then Present (Wrapped_Entity (Subp))
10273 Set_Referenced (Wrapped_Entity (Subp));
10278 end Check_Abstract_Overriding;
10280 ------------------------------------------------
10281 -- Check_Access_Discriminant_Requires_Limited --
10282 ------------------------------------------------
10284 procedure Check_Access_Discriminant_Requires_Limited
10289 -- A discriminant_specification for an access discriminant shall appear
10290 -- only in the declaration for a task or protected type, or for a type
10291 -- with the reserved word 'limited' in its definition or in one of its
10292 -- ancestors (RM 3.7(10)).
10294 -- AI-0063: The proper condition is that type must be immutably limited,
10295 -- or else be a partial view.
10297 if Nkind (Discriminant_Type (D)) = N_Access_Definition then
10298 if Is_Limited_View (Current_Scope)
10300 (Nkind (Parent (Current_Scope)) = N_Private_Type_Declaration
10301 and then Limited_Present (Parent (Current_Scope)))
10307 ("access discriminants allowed only for limited types", Loc);
10310 end Check_Access_Discriminant_Requires_Limited;
10312 -----------------------------------
10313 -- Check_Aliased_Component_Types --
10314 -----------------------------------
10316 procedure Check_Aliased_Component_Types (T : Entity_Id) is
10320 -- ??? Also need to check components of record extensions, but not
10321 -- components of protected types (which are always limited).
10323 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
10324 -- types to be unconstrained. This is safe because it is illegal to
10325 -- create access subtypes to such types with explicit discriminant
10328 if not Is_Limited_Type (T) then
10329 if Ekind (T) = E_Record_Type then
10330 C := First_Component (T);
10331 while Present (C) loop
10333 and then Has_Discriminants (Etype (C))
10334 and then not Is_Constrained (Etype (C))
10335 and then not In_Instance_Body
10336 and then Ada_Version < Ada_2005
10339 ("aliased component must be constrained (RM 3.6(11))",
10343 Next_Component (C);
10346 elsif Ekind (T) = E_Array_Type then
10347 if Has_Aliased_Components (T)
10348 and then Has_Discriminants (Component_Type (T))
10349 and then not Is_Constrained (Component_Type (T))
10350 and then not In_Instance_Body
10351 and then Ada_Version < Ada_2005
10354 ("aliased component type must be constrained (RM 3.6(11))",
10359 end Check_Aliased_Component_Types;
10361 ---------------------------------------
10362 -- Check_Anonymous_Access_Components --
10363 ---------------------------------------
10365 procedure Check_Anonymous_Access_Components
10366 (Typ_Decl : Node_Id;
10369 Comp_List : Node_Id)
10371 Loc : constant Source_Ptr := Sloc (Typ_Decl);
10372 Anon_Access : Entity_Id;
10375 Comp_Def : Node_Id;
10377 Type_Def : Node_Id;
10379 procedure Build_Incomplete_Type_Declaration;
10380 -- If the record type contains components that include an access to the
10381 -- current record, then create an incomplete type declaration for the
10382 -- record, to be used as the designated type of the anonymous access.
10383 -- This is done only once, and only if there is no previous partial
10384 -- view of the type.
10386 function Designates_T (Subt : Node_Id) return Boolean;
10387 -- Check whether a node designates the enclosing record type, or 'Class
10390 function Mentions_T (Acc_Def : Node_Id) return Boolean;
10391 -- Check whether an access definition includes a reference to
10392 -- the enclosing record type. The reference can be a subtype mark
10393 -- in the access definition itself, a 'Class attribute reference, or
10394 -- recursively a reference appearing in a parameter specification
10395 -- or result definition of an access_to_subprogram definition.
10397 --------------------------------------
10398 -- Build_Incomplete_Type_Declaration --
10399 --------------------------------------
10401 procedure Build_Incomplete_Type_Declaration is
10406 -- Is_Tagged indicates whether the type is tagged. It is tagged if
10407 -- it's "is new ... with record" or else "is tagged record ...".
10409 Is_Tagged : constant Boolean :=
10410 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
10412 Present (Record_Extension_Part (Type_Definition (Typ_Decl))))
10414 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
10415 and then Tagged_Present (Type_Definition (Typ_Decl)));
10418 -- If there is a previous partial view, no need to create a new one
10419 -- If the partial view, given by Prev, is incomplete, If Prev is
10420 -- a private declaration, full declaration is flagged accordingly.
10422 if Prev /= Typ then
10424 Make_Class_Wide_Type (Prev);
10425 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
10426 Set_Etype (Class_Wide_Type (Typ), Typ);
10431 elsif Has_Private_Declaration (Typ) then
10433 -- If we refer to T'Class inside T, and T is the completion of a
10434 -- private type, then make sure the class-wide type exists.
10437 Make_Class_Wide_Type (Typ);
10442 -- If there was a previous anonymous access type, the incomplete
10443 -- type declaration will have been created already.
10445 elsif Present (Current_Entity (Typ))
10446 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
10447 and then Full_View (Current_Entity (Typ)) = Typ
10450 and then Comes_From_Source (Current_Entity (Typ))
10451 and then not Is_Tagged_Type (Current_Entity (Typ))
10453 Make_Class_Wide_Type (Typ);
10455 ("incomplete view of tagged type should be declared tagged??",
10456 Parent (Current_Entity (Typ)));
10461 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
10462 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
10464 -- Type has already been inserted into the current scope. Remove
10465 -- it, and add incomplete declaration for type, so that subsequent
10466 -- anonymous access types can use it. The entity is unchained from
10467 -- the homonym list and from immediate visibility. After analysis,
10468 -- the entity in the incomplete declaration becomes immediately
10469 -- visible in the record declaration that follows.
10471 H := Current_Entity (Typ);
10474 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
10477 and then Homonym (H) /= Typ
10479 H := Homonym (Typ);
10482 Set_Homonym (H, Homonym (Typ));
10485 Insert_Before (Typ_Decl, Decl);
10487 Set_Full_View (Inc_T, Typ);
10491 -- Create a common class-wide type for both views, and set the
10492 -- Etype of the class-wide type to the full view.
10494 Make_Class_Wide_Type (Inc_T);
10495 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
10496 Set_Etype (Class_Wide_Type (Typ), Typ);
10499 end Build_Incomplete_Type_Declaration;
10505 function Designates_T (Subt : Node_Id) return Boolean is
10506 Type_Id : constant Name_Id := Chars (Typ);
10508 function Names_T (Nam : Node_Id) return Boolean;
10509 -- The record type has not been introduced in the current scope
10510 -- yet, so we must examine the name of the type itself, either
10511 -- an identifier T, or an expanded name of the form P.T, where
10512 -- P denotes the current scope.
10518 function Names_T (Nam : Node_Id) return Boolean is
10520 if Nkind (Nam) = N_Identifier then
10521 return Chars (Nam) = Type_Id;
10523 elsif Nkind (Nam) = N_Selected_Component then
10524 if Chars (Selector_Name (Nam)) = Type_Id then
10525 if Nkind (Prefix (Nam)) = N_Identifier then
10526 return Chars (Prefix (Nam)) = Chars (Current_Scope);
10528 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
10529 return Chars (Selector_Name (Prefix (Nam))) =
10530 Chars (Current_Scope);
10544 -- Start of processing for Designates_T
10547 if Nkind (Subt) = N_Identifier then
10548 return Chars (Subt) = Type_Id;
10550 -- Reference can be through an expanded name which has not been
10551 -- analyzed yet, and which designates enclosing scopes.
10553 elsif Nkind (Subt) = N_Selected_Component then
10554 if Names_T (Subt) then
10557 -- Otherwise it must denote an entity that is already visible.
10558 -- The access definition may name a subtype of the enclosing
10559 -- type, if there is a previous incomplete declaration for it.
10562 Find_Selected_Component (Subt);
10564 Is_Entity_Name (Subt)
10565 and then Scope (Entity (Subt)) = Current_Scope
10567 (Chars (Base_Type (Entity (Subt))) = Type_Id
10569 (Is_Class_Wide_Type (Entity (Subt))
10571 Chars (Etype (Base_Type (Entity (Subt)))) =
10575 -- A reference to the current type may appear as the prefix of
10576 -- a 'Class attribute.
10578 elsif Nkind (Subt) = N_Attribute_Reference
10579 and then Attribute_Name (Subt) = Name_Class
10581 return Names_T (Prefix (Subt));
10592 function Mentions_T (Acc_Def : Node_Id) return Boolean is
10593 Param_Spec : Node_Id;
10595 Acc_Subprg : constant Node_Id :=
10596 Access_To_Subprogram_Definition (Acc_Def);
10599 if No (Acc_Subprg) then
10600 return Designates_T (Subtype_Mark (Acc_Def));
10603 -- Component is an access_to_subprogram: examine its formals,
10604 -- and result definition in the case of an access_to_function.
10606 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
10607 while Present (Param_Spec) loop
10608 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
10609 and then Mentions_T (Parameter_Type (Param_Spec))
10613 elsif Designates_T (Parameter_Type (Param_Spec)) then
10620 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
10621 if Nkind (Result_Definition (Acc_Subprg)) =
10622 N_Access_Definition
10624 return Mentions_T (Result_Definition (Acc_Subprg));
10626 return Designates_T (Result_Definition (Acc_Subprg));
10633 -- Start of processing for Check_Anonymous_Access_Components
10636 if No (Comp_List) then
10640 Comp := First (Component_Items (Comp_List));
10641 while Present (Comp) loop
10642 if Nkind (Comp) = N_Component_Declaration
10644 (Access_Definition (Component_Definition (Comp)))
10646 Mentions_T (Access_Definition (Component_Definition (Comp)))
10648 Comp_Def := Component_Definition (Comp);
10650 Access_To_Subprogram_Definition (Access_Definition (Comp_Def));
10652 Build_Incomplete_Type_Declaration;
10653 Anon_Access := Make_Temporary (Loc, 'S');
10655 -- Create a declaration for the anonymous access type: either
10656 -- an access_to_object or an access_to_subprogram.
10658 if Present (Acc_Def) then
10659 if Nkind (Acc_Def) = N_Access_Function_Definition then
10661 Make_Access_Function_Definition (Loc,
10662 Parameter_Specifications =>
10663 Parameter_Specifications (Acc_Def),
10664 Result_Definition => Result_Definition (Acc_Def));
10667 Make_Access_Procedure_Definition (Loc,
10668 Parameter_Specifications =>
10669 Parameter_Specifications (Acc_Def));
10674 Make_Access_To_Object_Definition (Loc,
10675 Subtype_Indication =>
10677 (Subtype_Mark (Access_Definition (Comp_Def))));
10679 Set_Constant_Present
10680 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
10682 (Type_Def, All_Present (Access_Definition (Comp_Def)));
10685 Set_Null_Exclusion_Present
10687 Null_Exclusion_Present (Access_Definition (Comp_Def)));
10690 Make_Full_Type_Declaration (Loc,
10691 Defining_Identifier => Anon_Access,
10692 Type_Definition => Type_Def);
10694 Insert_Before (Typ_Decl, Decl);
10697 -- If an access to subprogram, create the extra formals
10699 if Present (Acc_Def) then
10700 Create_Extra_Formals (Designated_Type (Anon_Access));
10702 -- If an access to object, preserve entity of designated type,
10703 -- for ASIS use, before rewriting the component definition.
10710 Desig := Entity (Subtype_Indication (Type_Def));
10712 -- If the access definition is to the current record,
10713 -- the visible entity at this point is an incomplete
10714 -- type. Retrieve the full view to simplify ASIS queries
10716 if Ekind (Desig) = E_Incomplete_Type then
10717 Desig := Full_View (Desig);
10721 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
10726 Make_Component_Definition (Loc,
10727 Subtype_Indication =>
10728 New_Occurrence_Of (Anon_Access, Loc)));
10730 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
10731 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
10733 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
10736 Set_Is_Local_Anonymous_Access (Anon_Access);
10742 if Present (Variant_Part (Comp_List)) then
10746 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
10747 while Present (V) loop
10748 Check_Anonymous_Access_Components
10749 (Typ_Decl, Typ, Prev, Component_List (V));
10750 Next_Non_Pragma (V);
10754 end Check_Anonymous_Access_Components;
10756 ----------------------
10757 -- Check_Completion --
10758 ----------------------
10760 procedure Check_Completion (Body_Id : Node_Id := Empty) is
10763 procedure Post_Error;
10764 -- Post error message for lack of completion for entity E
10770 procedure Post_Error is
10771 procedure Missing_Body;
10772 -- Output missing body message
10778 procedure Missing_Body is
10780 -- Spec is in same unit, so we can post on spec
10782 if In_Same_Source_Unit (Body_Id, E) then
10783 Error_Msg_N ("missing body for &", E);
10785 -- Spec is in a separate unit, so we have to post on the body
10788 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
10792 -- Start of processing for Post_Error
10795 if not Comes_From_Source (E) then
10796 if Ekind_In (E, E_Task_Type, E_Protected_Type) then
10798 -- It may be an anonymous protected type created for a
10799 -- single variable. Post error on variable, if present.
10805 Var := First_Entity (Current_Scope);
10806 while Present (Var) loop
10807 exit when Etype (Var) = E
10808 and then Comes_From_Source (Var);
10813 if Present (Var) then
10820 -- If a generated entity has no completion, then either previous
10821 -- semantic errors have disabled the expansion phase, or else we had
10822 -- missing subunits, or else we are compiling without expansion,
10823 -- or else something is very wrong.
10825 if not Comes_From_Source (E) then
10827 (Serious_Errors_Detected > 0
10828 or else Configurable_Run_Time_Violations > 0
10829 or else Subunits_Missing
10830 or else not Expander_Active);
10833 -- Here for source entity
10836 -- Here if no body to post the error message, so we post the error
10837 -- on the declaration that has no completion. This is not really
10838 -- the right place to post it, think about this later ???
10840 if No (Body_Id) then
10841 if Is_Type (E) then
10843 ("missing full declaration for }", Parent (E), E);
10845 Error_Msg_NE ("missing body for &", Parent (E), E);
10848 -- Package body has no completion for a declaration that appears
10849 -- in the corresponding spec. Post error on the body, with a
10850 -- reference to the non-completed declaration.
10853 Error_Msg_Sloc := Sloc (E);
10855 if Is_Type (E) then
10856 Error_Msg_NE ("missing full declaration for }!", Body_Id, E);
10858 elsif Is_Overloadable (E)
10859 and then Current_Entity_In_Scope (E) /= E
10861 -- It may be that the completion is mistyped and appears as
10862 -- a distinct overloading of the entity.
10865 Candidate : constant Entity_Id :=
10866 Current_Entity_In_Scope (E);
10867 Decl : constant Node_Id :=
10868 Unit_Declaration_Node (Candidate);
10871 if Is_Overloadable (Candidate)
10872 and then Ekind (Candidate) = Ekind (E)
10873 and then Nkind (Decl) = N_Subprogram_Body
10874 and then Acts_As_Spec (Decl)
10876 Check_Type_Conformant (Candidate, E);
10892 Pack_Id : constant Entity_Id := Current_Scope;
10894 -- Start of processing for Check_Completion
10897 E := First_Entity (Pack_Id);
10898 while Present (E) loop
10899 if Is_Intrinsic_Subprogram (E) then
10902 -- The following situation requires special handling: a child unit
10903 -- that appears in the context clause of the body of its parent:
10905 -- procedure Parent.Child (...);
10907 -- with Parent.Child;
10908 -- package body Parent is
10910 -- Here Parent.Child appears as a local entity, but should not be
10911 -- flagged as requiring completion, because it is a compilation
10914 -- Ignore missing completion for a subprogram that does not come from
10915 -- source (including the _Call primitive operation of RAS types,
10916 -- which has to have the flag Comes_From_Source for other purposes):
10917 -- we assume that the expander will provide the missing completion.
10918 -- In case of previous errors, other expansion actions that provide
10919 -- bodies for null procedures with not be invoked, so inhibit message
10922 -- Note that E_Operator is not in the list that follows, because
10923 -- this kind is reserved for predefined operators, that are
10924 -- intrinsic and do not need completion.
10926 elsif Ekind_In (E, E_Function,
10928 E_Generic_Function,
10929 E_Generic_Procedure)
10931 if Has_Completion (E) then
10934 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
10937 elsif Is_Subprogram (E)
10938 and then (not Comes_From_Source (E)
10939 or else Chars (E) = Name_uCall)
10944 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
10948 elsif Nkind (Parent (E)) = N_Procedure_Specification
10949 and then Null_Present (Parent (E))
10950 and then Serious_Errors_Detected > 0
10958 elsif Is_Entry (E) then
10959 if not Has_Completion (E) and then
10960 (Ekind (Scope (E)) = E_Protected_Object
10961 or else Ekind (Scope (E)) = E_Protected_Type)
10966 elsif Is_Package_Or_Generic_Package (E) then
10967 if Unit_Requires_Body (E) then
10968 if not Has_Completion (E)
10969 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
10975 elsif not Is_Child_Unit (E) then
10976 May_Need_Implicit_Body (E);
10979 -- A formal incomplete type (Ada 2012) does not require a completion;
10980 -- other incomplete type declarations do.
10982 elsif Ekind (E) = E_Incomplete_Type
10983 and then No (Underlying_Type (E))
10984 and then not Is_Generic_Type (E)
10988 elsif Ekind_In (E, E_Task_Type, E_Protected_Type)
10989 and then not Has_Completion (E)
10993 -- A single task declared in the current scope is a constant, verify
10994 -- that the body of its anonymous type is in the same scope. If the
10995 -- task is defined elsewhere, this may be a renaming declaration for
10996 -- which no completion is needed.
10998 elsif Ekind (E) = E_Constant
10999 and then Ekind (Etype (E)) = E_Task_Type
11000 and then not Has_Completion (Etype (E))
11001 and then Scope (Etype (E)) = Current_Scope
11005 elsif Ekind (E) = E_Protected_Object
11006 and then not Has_Completion (Etype (E))
11010 elsif Ekind (E) = E_Record_Type then
11011 if Is_Tagged_Type (E) then
11012 Check_Abstract_Overriding (E);
11013 Check_Conventions (E);
11016 Check_Aliased_Component_Types (E);
11018 elsif Ekind (E) = E_Array_Type then
11019 Check_Aliased_Component_Types (E);
11025 end Check_Completion;
11027 ------------------------------------
11028 -- Check_CPP_Type_Has_No_Defaults --
11029 ------------------------------------
11031 procedure Check_CPP_Type_Has_No_Defaults (T : Entity_Id) is
11032 Tdef : constant Node_Id := Type_Definition (Declaration_Node (T));
11037 -- Obtain the component list
11039 if Nkind (Tdef) = N_Record_Definition then
11040 Clist := Component_List (Tdef);
11041 else pragma Assert (Nkind (Tdef) = N_Derived_Type_Definition);
11042 Clist := Component_List (Record_Extension_Part (Tdef));
11045 -- Check all components to ensure no default expressions
11047 if Present (Clist) then
11048 Comp := First (Component_Items (Clist));
11049 while Present (Comp) loop
11050 if Present (Expression (Comp)) then
11052 ("component of imported 'C'P'P type cannot have "
11053 & "default expression", Expression (Comp));
11059 end Check_CPP_Type_Has_No_Defaults;
11061 ----------------------------
11062 -- Check_Delta_Expression --
11063 ----------------------------
11065 procedure Check_Delta_Expression (E : Node_Id) is
11067 if not (Is_Real_Type (Etype (E))) then
11068 Wrong_Type (E, Any_Real);
11070 elsif not Is_OK_Static_Expression (E) then
11071 Flag_Non_Static_Expr
11072 ("non-static expression used for delta value!", E);
11074 elsif not UR_Is_Positive (Expr_Value_R (E)) then
11075 Error_Msg_N ("delta expression must be positive", E);
11081 -- If any of above errors occurred, then replace the incorrect
11082 -- expression by the real 0.1, which should prevent further errors.
11085 Make_Real_Literal (Sloc (E), Ureal_Tenth));
11086 Analyze_And_Resolve (E, Standard_Float);
11087 end Check_Delta_Expression;
11089 -----------------------------
11090 -- Check_Digits_Expression --
11091 -----------------------------
11093 procedure Check_Digits_Expression (E : Node_Id) is
11095 if not (Is_Integer_Type (Etype (E))) then
11096 Wrong_Type (E, Any_Integer);
11098 elsif not Is_OK_Static_Expression (E) then
11099 Flag_Non_Static_Expr
11100 ("non-static expression used for digits value!", E);
11102 elsif Expr_Value (E) <= 0 then
11103 Error_Msg_N ("digits value must be greater than zero", E);
11109 -- If any of above errors occurred, then replace the incorrect
11110 -- expression by the integer 1, which should prevent further errors.
11112 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
11113 Analyze_And_Resolve (E, Standard_Integer);
11115 end Check_Digits_Expression;
11117 --------------------------
11118 -- Check_Initialization --
11119 --------------------------
11121 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
11123 -- Special processing for limited types
11125 if Is_Limited_Type (T)
11126 and then not In_Instance
11127 and then not In_Inlined_Body
11129 if not OK_For_Limited_Init (T, Exp) then
11131 -- In GNAT mode, this is just a warning, to allow it to be evilly
11132 -- turned off. Otherwise it is a real error.
11136 ("??cannot initialize entities of limited type!", Exp);
11138 elsif Ada_Version < Ada_2005 then
11140 -- The side effect removal machinery may generate illegal Ada
11141 -- code to avoid the usage of access types and 'reference in
11142 -- SPARK mode. Since this is legal code with respect to theorem
11143 -- proving, do not emit the error.
11146 and then Nkind (Exp) = N_Function_Call
11147 and then Nkind (Parent (Exp)) = N_Object_Declaration
11148 and then not Comes_From_Source
11149 (Defining_Identifier (Parent (Exp)))
11155 ("cannot initialize entities of limited type", Exp);
11156 Explain_Limited_Type (T, Exp);
11160 -- Specialize error message according to kind of illegal
11161 -- initial expression.
11163 if Nkind (Exp) = N_Type_Conversion
11164 and then Nkind (Expression (Exp)) = N_Function_Call
11167 ("illegal context for call"
11168 & " to function with limited result", Exp);
11172 ("initialization of limited object requires aggregate "
11173 & "or function call", Exp);
11179 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag gets
11180 -- set unless we can be sure that no range check is required.
11182 if (GNATprove_Mode or not Expander_Active)
11183 and then Is_Scalar_Type (T)
11184 and then not Is_In_Range (Exp, T, Assume_Valid => True)
11186 Set_Do_Range_Check (Exp);
11188 end Check_Initialization;
11190 ----------------------
11191 -- Check_Interfaces --
11192 ----------------------
11194 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
11195 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
11198 Iface_Def : Node_Id;
11199 Iface_Typ : Entity_Id;
11200 Parent_Node : Node_Id;
11202 Is_Task : Boolean := False;
11203 -- Set True if parent type or any progenitor is a task interface
11205 Is_Protected : Boolean := False;
11206 -- Set True if parent type or any progenitor is a protected interface
11208 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
11209 -- Check that a progenitor is compatible with declaration. If an error
11210 -- message is output, it is posted on Error_Node.
11216 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
11217 Iface_Id : constant Entity_Id :=
11218 Defining_Identifier (Parent (Iface_Def));
11219 Type_Def : Node_Id;
11222 if Nkind (N) = N_Private_Extension_Declaration then
11225 Type_Def := Type_Definition (N);
11228 if Is_Task_Interface (Iface_Id) then
11231 elsif Is_Protected_Interface (Iface_Id) then
11232 Is_Protected := True;
11235 if Is_Synchronized_Interface (Iface_Id) then
11237 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
11238 -- extension derived from a synchronized interface must explicitly
11239 -- be declared synchronized, because the full view will be a
11240 -- synchronized type.
11242 if Nkind (N) = N_Private_Extension_Declaration then
11243 if not Synchronized_Present (N) then
11245 ("private extension of& must be explicitly synchronized",
11249 -- However, by 3.9.4(16/2), a full type that is a record extension
11250 -- is never allowed to derive from a synchronized interface (note
11251 -- that interfaces must be excluded from this check, because those
11252 -- are represented by derived type definitions in some cases).
11254 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11255 and then not Interface_Present (Type_Definition (N))
11257 Error_Msg_N ("record extension cannot derive from synchronized "
11258 & "interface", Error_Node);
11262 -- Check that the characteristics of the progenitor are compatible
11263 -- with the explicit qualifier in the declaration.
11264 -- The check only applies to qualifiers that come from source.
11265 -- Limited_Present also appears in the declaration of corresponding
11266 -- records, and the check does not apply to them.
11268 if Limited_Present (Type_Def)
11270 Is_Concurrent_Record_Type (Defining_Identifier (N))
11272 if Is_Limited_Interface (Parent_Type)
11273 and then not Is_Limited_Interface (Iface_Id)
11276 ("progenitor & must be limited interface",
11277 Error_Node, Iface_Id);
11280 (Task_Present (Iface_Def)
11281 or else Protected_Present (Iface_Def)
11282 or else Synchronized_Present (Iface_Def))
11283 and then Nkind (N) /= N_Private_Extension_Declaration
11284 and then not Error_Posted (N)
11287 ("progenitor & must be limited interface",
11288 Error_Node, Iface_Id);
11291 -- Protected interfaces can only inherit from limited, synchronized
11292 -- or protected interfaces.
11294 elsif Nkind (N) = N_Full_Type_Declaration
11295 and then Protected_Present (Type_Def)
11297 if Limited_Present (Iface_Def)
11298 or else Synchronized_Present (Iface_Def)
11299 or else Protected_Present (Iface_Def)
11303 elsif Task_Present (Iface_Def) then
11304 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11305 & "from task interface", Error_Node);
11308 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11309 & "from non-limited interface", Error_Node);
11312 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
11313 -- limited and synchronized.
11315 elsif Synchronized_Present (Type_Def) then
11316 if Limited_Present (Iface_Def)
11317 or else Synchronized_Present (Iface_Def)
11321 elsif Protected_Present (Iface_Def)
11322 and then Nkind (N) /= N_Private_Extension_Declaration
11324 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11325 & "from protected interface", Error_Node);
11327 elsif Task_Present (Iface_Def)
11328 and then Nkind (N) /= N_Private_Extension_Declaration
11330 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11331 & "from task interface", Error_Node);
11333 elsif not Is_Limited_Interface (Iface_Id) then
11334 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11335 & "from non-limited interface", Error_Node);
11338 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
11339 -- synchronized or task interfaces.
11341 elsif Nkind (N) = N_Full_Type_Declaration
11342 and then Task_Present (Type_Def)
11344 if Limited_Present (Iface_Def)
11345 or else Synchronized_Present (Iface_Def)
11346 or else Task_Present (Iface_Def)
11350 elsif Protected_Present (Iface_Def) then
11351 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11352 & "protected interface", Error_Node);
11355 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11356 & "non-limited interface", Error_Node);
11361 -- Start of processing for Check_Interfaces
11364 if Is_Interface (Parent_Type) then
11365 if Is_Task_Interface (Parent_Type) then
11368 elsif Is_Protected_Interface (Parent_Type) then
11369 Is_Protected := True;
11373 if Nkind (N) = N_Private_Extension_Declaration then
11375 -- Check that progenitors are compatible with declaration
11377 Iface := First (Interface_List (Def));
11378 while Present (Iface) loop
11379 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11381 Parent_Node := Parent (Base_Type (Iface_Typ));
11382 Iface_Def := Type_Definition (Parent_Node);
11384 if not Is_Interface (Iface_Typ) then
11385 Diagnose_Interface (Iface, Iface_Typ);
11387 Check_Ifaces (Iface_Def, Iface);
11393 if Is_Task and Is_Protected then
11395 ("type cannot derive from task and protected interface", N);
11401 -- Full type declaration of derived type.
11402 -- Check compatibility with parent if it is interface type
11404 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11405 and then Is_Interface (Parent_Type)
11407 Parent_Node := Parent (Parent_Type);
11409 -- More detailed checks for interface varieties
11412 (Iface_Def => Type_Definition (Parent_Node),
11413 Error_Node => Subtype_Indication (Type_Definition (N)));
11416 Iface := First (Interface_List (Def));
11417 while Present (Iface) loop
11418 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11420 Parent_Node := Parent (Base_Type (Iface_Typ));
11421 Iface_Def := Type_Definition (Parent_Node);
11423 if not Is_Interface (Iface_Typ) then
11424 Diagnose_Interface (Iface, Iface_Typ);
11427 -- "The declaration of a specific descendant of an interface
11428 -- type freezes the interface type" RM 13.14
11430 Freeze_Before (N, Iface_Typ);
11431 Check_Ifaces (Iface_Def, Error_Node => Iface);
11437 if Is_Task and Is_Protected then
11439 ("type cannot derive from task and protected interface", N);
11441 end Check_Interfaces;
11443 ------------------------------------
11444 -- Check_Or_Process_Discriminants --
11445 ------------------------------------
11447 -- If an incomplete or private type declaration was already given for the
11448 -- type, the discriminants may have already been processed if they were
11449 -- present on the incomplete declaration. In this case a full conformance
11450 -- check has been performed in Find_Type_Name, and we then recheck here
11451 -- some properties that can't be checked on the partial view alone.
11452 -- Otherwise we call Process_Discriminants.
11454 procedure Check_Or_Process_Discriminants
11457 Prev : Entity_Id := Empty)
11460 if Has_Discriminants (T) then
11462 -- Discriminants are already set on T if they were already present
11463 -- on the partial view. Make them visible to component declarations.
11467 -- Discriminant on T (full view) referencing expr on partial view
11469 Prev_D : Entity_Id;
11470 -- Entity of corresponding discriminant on partial view
11473 -- Discriminant specification for full view, expression is
11474 -- the syntactic copy on full view (which has been checked for
11475 -- conformance with partial view), only used here to post error
11479 D := First_Discriminant (T);
11480 New_D := First (Discriminant_Specifications (N));
11481 while Present (D) loop
11482 Prev_D := Current_Entity (D);
11483 Set_Current_Entity (D);
11484 Set_Is_Immediately_Visible (D);
11485 Set_Homonym (D, Prev_D);
11487 -- Handle the case where there is an untagged partial view and
11488 -- the full view is tagged: must disallow discriminants with
11489 -- defaults, unless compiling for Ada 2012, which allows a
11490 -- limited tagged type to have defaulted discriminants (see
11491 -- AI05-0214). However, suppress error here if it was already
11492 -- reported on the default expression of the partial view.
11494 if Is_Tagged_Type (T)
11495 and then Present (Expression (Parent (D)))
11496 and then (not Is_Limited_Type (Current_Scope)
11497 or else Ada_Version < Ada_2012)
11498 and then not Error_Posted (Expression (Parent (D)))
11500 if Ada_Version >= Ada_2012 then
11502 ("discriminants of nonlimited tagged type cannot have "
11504 Expression (New_D));
11507 ("discriminants of tagged type cannot have defaults",
11508 Expression (New_D));
11512 -- Ada 2005 (AI-230): Access discriminant allowed in
11513 -- non-limited record types.
11515 if Ada_Version < Ada_2005 then
11517 -- This restriction gets applied to the full type here. It
11518 -- has already been applied earlier to the partial view.
11520 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
11523 Next_Discriminant (D);
11528 elsif Present (Discriminant_Specifications (N)) then
11529 Process_Discriminants (N, Prev);
11531 end Check_Or_Process_Discriminants;
11533 ----------------------
11534 -- Check_Real_Bound --
11535 ----------------------
11537 procedure Check_Real_Bound (Bound : Node_Id) is
11539 if not Is_Real_Type (Etype (Bound)) then
11541 ("bound in real type definition must be of real type", Bound);
11543 elsif not Is_OK_Static_Expression (Bound) then
11544 Flag_Non_Static_Expr
11545 ("non-static expression used for real type bound!", Bound);
11552 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
11554 Resolve (Bound, Standard_Float);
11555 end Check_Real_Bound;
11557 ------------------------------
11558 -- Complete_Private_Subtype --
11559 ------------------------------
11561 procedure Complete_Private_Subtype
11564 Full_Base : Entity_Id;
11565 Related_Nod : Node_Id)
11567 Save_Next_Entity : Entity_Id;
11568 Save_Homonym : Entity_Id;
11571 -- Set semantic attributes for (implicit) private subtype completion.
11572 -- If the full type has no discriminants, then it is a copy of the
11573 -- full view of the base. Otherwise, it is a subtype of the base with
11574 -- a possible discriminant constraint. Save and restore the original
11575 -- Next_Entity field of full to ensure that the calls to Copy_Node do
11576 -- not corrupt the entity chain.
11578 -- Note that the type of the full view is the same entity as the type
11579 -- of the partial view. In this fashion, the subtype has access to the
11580 -- correct view of the parent.
11582 Save_Next_Entity := Next_Entity (Full);
11583 Save_Homonym := Homonym (Priv);
11585 case Ekind (Full_Base) is
11586 when E_Record_Type |
11592 Copy_Node (Priv, Full);
11594 Set_Has_Discriminants
11595 (Full, Has_Discriminants (Full_Base));
11596 Set_Has_Unknown_Discriminants
11597 (Full, Has_Unknown_Discriminants (Full_Base));
11598 Set_First_Entity (Full, First_Entity (Full_Base));
11599 Set_Last_Entity (Full, Last_Entity (Full_Base));
11601 -- If the underlying base type is constrained, we know that the
11602 -- full view of the subtype is constrained as well (the converse
11603 -- is not necessarily true).
11605 if Is_Constrained (Full_Base) then
11606 Set_Is_Constrained (Full);
11610 Copy_Node (Full_Base, Full);
11612 Set_Chars (Full, Chars (Priv));
11613 Conditional_Delay (Full, Priv);
11614 Set_Sloc (Full, Sloc (Priv));
11617 Set_Next_Entity (Full, Save_Next_Entity);
11618 Set_Homonym (Full, Save_Homonym);
11619 Set_Associated_Node_For_Itype (Full, Related_Nod);
11621 -- Set common attributes for all subtypes: kind, convention, etc.
11623 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
11624 Set_Convention (Full, Convention (Full_Base));
11626 -- The Etype of the full view is inconsistent. Gigi needs to see the
11627 -- structural full view, which is what the current scheme gives: the
11628 -- Etype of the full view is the etype of the full base. However, if the
11629 -- full base is a derived type, the full view then looks like a subtype
11630 -- of the parent, not a subtype of the full base. If instead we write:
11632 -- Set_Etype (Full, Full_Base);
11634 -- then we get inconsistencies in the front-end (confusion between
11635 -- views). Several outstanding bugs are related to this ???
11637 Set_Is_First_Subtype (Full, False);
11638 Set_Scope (Full, Scope (Priv));
11639 Set_Size_Info (Full, Full_Base);
11640 Set_RM_Size (Full, RM_Size (Full_Base));
11641 Set_Is_Itype (Full);
11643 -- A subtype of a private-type-without-discriminants, whose full-view
11644 -- has discriminants with default expressions, is not constrained.
11646 if not Has_Discriminants (Priv) then
11647 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
11649 if Has_Discriminants (Full_Base) then
11650 Set_Discriminant_Constraint
11651 (Full, Discriminant_Constraint (Full_Base));
11653 -- The partial view may have been indefinite, the full view
11656 Set_Has_Unknown_Discriminants
11657 (Full, Has_Unknown_Discriminants (Full_Base));
11661 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
11662 Set_Depends_On_Private (Full, Has_Private_Component (Full));
11664 -- Freeze the private subtype entity if its parent is delayed, and not
11665 -- already frozen. We skip this processing if the type is an anonymous
11666 -- subtype of a record component, or is the corresponding record of a
11667 -- protected type, since these are processed when the enclosing type
11670 if not Is_Type (Scope (Full)) then
11671 Set_Has_Delayed_Freeze (Full,
11672 Has_Delayed_Freeze (Full_Base)
11673 and then (not Is_Frozen (Full_Base)));
11676 Set_Freeze_Node (Full, Empty);
11677 Set_Is_Frozen (Full, False);
11678 Set_Full_View (Priv, Full);
11680 if Has_Discriminants (Full) then
11681 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
11682 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
11684 if Has_Unknown_Discriminants (Full) then
11685 Set_Discriminant_Constraint (Full, No_Elist);
11689 if Ekind (Full_Base) = E_Record_Type
11690 and then Has_Discriminants (Full_Base)
11691 and then Has_Discriminants (Priv) -- might not, if errors
11692 and then not Has_Unknown_Discriminants (Priv)
11693 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
11695 Create_Constrained_Components
11696 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
11698 -- If the full base is itself derived from private, build a congruent
11699 -- subtype of its underlying type, for use by the back end. For a
11700 -- constrained record component, the declaration cannot be placed on
11701 -- the component list, but it must nevertheless be built an analyzed, to
11702 -- supply enough information for Gigi to compute the size of component.
11704 elsif Ekind (Full_Base) in Private_Kind
11705 and then Is_Derived_Type (Full_Base)
11706 and then Has_Discriminants (Full_Base)
11707 and then (Ekind (Current_Scope) /= E_Record_Subtype)
11709 if not Is_Itype (Priv)
11711 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
11713 Build_Underlying_Full_View
11714 (Parent (Priv), Full, Etype (Full_Base));
11716 elsif Nkind (Related_Nod) = N_Component_Declaration then
11717 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
11720 elsif Is_Record_Type (Full_Base) then
11722 -- Show Full is simply a renaming of Full_Base
11724 Set_Cloned_Subtype (Full, Full_Base);
11727 -- It is unsafe to share the bounds of a scalar type, because the Itype
11728 -- is elaborated on demand, and if a bound is non-static then different
11729 -- orders of elaboration in different units will lead to different
11730 -- external symbols.
11732 if Is_Scalar_Type (Full_Base) then
11733 Set_Scalar_Range (Full,
11734 Make_Range (Sloc (Related_Nod),
11736 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
11738 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
11740 -- This completion inherits the bounds of the full parent, but if
11741 -- the parent is an unconstrained floating point type, so is the
11744 if Is_Floating_Point_Type (Full_Base) then
11745 Set_Includes_Infinities
11746 (Scalar_Range (Full), Has_Infinities (Full_Base));
11750 -- ??? It seems that a lot of fields are missing that should be copied
11751 -- from Full_Base to Full. Here are some that are introduced in a
11752 -- non-disruptive way but a cleanup is necessary.
11754 if Is_Tagged_Type (Full_Base) then
11755 Set_Is_Tagged_Type (Full);
11756 Set_Direct_Primitive_Operations
11757 (Full, Direct_Primitive_Operations (Full_Base));
11758 Set_No_Tagged_Streams_Pragma
11759 (Full, No_Tagged_Streams_Pragma (Full_Base));
11761 -- Inherit class_wide type of full_base in case the partial view was
11762 -- not tagged. Otherwise it has already been created when the private
11763 -- subtype was analyzed.
11765 if No (Class_Wide_Type (Full)) then
11766 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
11769 -- If this is a subtype of a protected or task type, constrain its
11770 -- corresponding record, unless this is a subtype without constraints,
11771 -- i.e. a simple renaming as with an actual subtype in an instance.
11773 elsif Is_Concurrent_Type (Full_Base) then
11774 if Has_Discriminants (Full)
11775 and then Present (Corresponding_Record_Type (Full_Base))
11777 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
11779 Set_Corresponding_Record_Type (Full,
11780 Constrain_Corresponding_Record
11781 (Full, Corresponding_Record_Type (Full_Base), Related_Nod));
11784 Set_Corresponding_Record_Type (Full,
11785 Corresponding_Record_Type (Full_Base));
11789 -- Link rep item chain, and also setting of Has_Predicates from private
11790 -- subtype to full subtype, since we will need these on the full subtype
11791 -- to create the predicate function. Note that the full subtype may
11792 -- already have rep items, inherited from the full view of the base
11793 -- type, so we must be sure not to overwrite these entries.
11798 Next_Item : Node_Id;
11801 Item := First_Rep_Item (Full);
11803 -- If no existing rep items on full type, we can just link directly
11804 -- to the list of items on the private type, if any exist.. Same if
11805 -- the rep items are only those inherited from the base
11808 or else Nkind (Item) /= N_Aspect_Specification
11809 or else Entity (Item) = Full_Base)
11810 and then Present (First_Rep_Item (Priv))
11812 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
11814 -- Otherwise, search to the end of items currently linked to the full
11815 -- subtype and append the private items to the end. However, if Priv
11816 -- and Full already have the same list of rep items, then the append
11817 -- is not done, as that would create a circularity.
11819 elsif Item /= First_Rep_Item (Priv) then
11822 Next_Item := Next_Rep_Item (Item);
11823 exit when No (Next_Item);
11826 -- If the private view has aspect specifications, the full view
11827 -- inherits them. Since these aspects may already have been
11828 -- attached to the full view during derivation, do not append
11829 -- them if already present.
11831 if Item = First_Rep_Item (Priv) then
11837 -- And link the private type items at the end of the chain
11840 Set_Next_Rep_Item (Item, First_Rep_Item (Priv));
11845 -- Make sure Has_Predicates is set on full type if it is set on the
11846 -- private type. Note that it may already be set on the full type and
11847 -- if so, we don't want to unset it. Similarly, propagate information
11848 -- about delayed aspects, because the corresponding pragmas must be
11849 -- analyzed when one of the views is frozen. This last step is needed
11850 -- in particular when the full type is a scalar type for which an
11851 -- anonymous base type is constructed.
11853 if Has_Predicates (Priv) then
11854 Set_Has_Predicates (Full);
11857 if Has_Delayed_Aspects (Priv) then
11858 Set_Has_Delayed_Aspects (Full);
11860 end Complete_Private_Subtype;
11862 ----------------------------
11863 -- Constant_Redeclaration --
11864 ----------------------------
11866 procedure Constant_Redeclaration
11871 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
11872 Obj_Def : constant Node_Id := Object_Definition (N);
11875 procedure Check_Possible_Deferred_Completion
11876 (Prev_Id : Entity_Id;
11877 Prev_Obj_Def : Node_Id;
11878 Curr_Obj_Def : Node_Id);
11879 -- Determine whether the two object definitions describe the partial
11880 -- and the full view of a constrained deferred constant. Generate
11881 -- a subtype for the full view and verify that it statically matches
11882 -- the subtype of the partial view.
11884 procedure Check_Recursive_Declaration (Typ : Entity_Id);
11885 -- If deferred constant is an access type initialized with an allocator,
11886 -- check whether there is an illegal recursion in the definition,
11887 -- through a default value of some record subcomponent. This is normally
11888 -- detected when generating init procs, but requires this additional
11889 -- mechanism when expansion is disabled.
11891 ----------------------------------------
11892 -- Check_Possible_Deferred_Completion --
11893 ----------------------------------------
11895 procedure Check_Possible_Deferred_Completion
11896 (Prev_Id : Entity_Id;
11897 Prev_Obj_Def : Node_Id;
11898 Curr_Obj_Def : Node_Id)
11901 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
11902 and then Present (Constraint (Prev_Obj_Def))
11903 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
11904 and then Present (Constraint (Curr_Obj_Def))
11907 Loc : constant Source_Ptr := Sloc (N);
11908 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'S');
11909 Decl : constant Node_Id :=
11910 Make_Subtype_Declaration (Loc,
11911 Defining_Identifier => Def_Id,
11912 Subtype_Indication =>
11913 Relocate_Node (Curr_Obj_Def));
11916 Insert_Before_And_Analyze (N, Decl);
11917 Set_Etype (Id, Def_Id);
11919 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
11920 Error_Msg_Sloc := Sloc (Prev_Id);
11921 Error_Msg_N ("subtype does not statically match deferred "
11922 & "declaration #", N);
11926 end Check_Possible_Deferred_Completion;
11928 ---------------------------------
11929 -- Check_Recursive_Declaration --
11930 ---------------------------------
11932 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
11936 if Is_Record_Type (Typ) then
11937 Comp := First_Component (Typ);
11938 while Present (Comp) loop
11939 if Comes_From_Source (Comp) then
11940 if Present (Expression (Parent (Comp)))
11941 and then Is_Entity_Name (Expression (Parent (Comp)))
11942 and then Entity (Expression (Parent (Comp))) = Prev
11944 Error_Msg_Sloc := Sloc (Parent (Comp));
11946 ("illegal circularity with declaration for & #",
11950 elsif Is_Record_Type (Etype (Comp)) then
11951 Check_Recursive_Declaration (Etype (Comp));
11955 Next_Component (Comp);
11958 end Check_Recursive_Declaration;
11960 -- Start of processing for Constant_Redeclaration
11963 if Nkind (Parent (Prev)) = N_Object_Declaration then
11964 if Nkind (Object_Definition
11965 (Parent (Prev))) = N_Subtype_Indication
11967 -- Find type of new declaration. The constraints of the two
11968 -- views must match statically, but there is no point in
11969 -- creating an itype for the full view.
11971 if Nkind (Obj_Def) = N_Subtype_Indication then
11972 Find_Type (Subtype_Mark (Obj_Def));
11973 New_T := Entity (Subtype_Mark (Obj_Def));
11976 Find_Type (Obj_Def);
11977 New_T := Entity (Obj_Def);
11983 -- The full view may impose a constraint, even if the partial
11984 -- view does not, so construct the subtype.
11986 New_T := Find_Type_Of_Object (Obj_Def, N);
11991 -- Current declaration is illegal, diagnosed below in Enter_Name
11997 -- If previous full declaration or a renaming declaration exists, or if
11998 -- a homograph is present, let Enter_Name handle it, either with an
11999 -- error or with the removal of an overridden implicit subprogram.
12000 -- The previous one is a full declaration if it has an expression
12001 -- (which in the case of an aggregate is indicated by the Init flag).
12003 if Ekind (Prev) /= E_Constant
12004 or else Nkind (Parent (Prev)) = N_Object_Renaming_Declaration
12005 or else Present (Expression (Parent (Prev)))
12006 or else Has_Init_Expression (Parent (Prev))
12007 or else Present (Full_View (Prev))
12011 -- Verify that types of both declarations match, or else that both types
12012 -- are anonymous access types whose designated subtypes statically match
12013 -- (as allowed in Ada 2005 by AI-385).
12015 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
12017 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
12018 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
12019 or else Is_Access_Constant (Etype (New_T)) /=
12020 Is_Access_Constant (Etype (Prev))
12021 or else Can_Never_Be_Null (Etype (New_T)) /=
12022 Can_Never_Be_Null (Etype (Prev))
12023 or else Null_Exclusion_Present (Parent (Prev)) /=
12024 Null_Exclusion_Present (Parent (Id))
12025 or else not Subtypes_Statically_Match
12026 (Designated_Type (Etype (Prev)),
12027 Designated_Type (Etype (New_T))))
12029 Error_Msg_Sloc := Sloc (Prev);
12030 Error_Msg_N ("type does not match declaration#", N);
12031 Set_Full_View (Prev, Id);
12032 Set_Etype (Id, Any_Type);
12034 -- A deferred constant whose type is an anonymous array is always
12035 -- illegal (unless imported). A detailed error message might be
12036 -- helpful for Ada beginners.
12038 if Nkind (Object_Definition (Parent (Prev)))
12039 = N_Constrained_Array_Definition
12040 and then Nkind (Object_Definition (N))
12041 = N_Constrained_Array_Definition
12043 Error_Msg_N ("\each anonymous array is a distinct type", N);
12044 Error_Msg_N ("a deferred constant must have a named type",
12045 Object_Definition (Parent (Prev)));
12049 Null_Exclusion_Present (Parent (Prev))
12050 and then not Null_Exclusion_Present (N)
12052 Error_Msg_Sloc := Sloc (Prev);
12053 Error_Msg_N ("null-exclusion does not match declaration#", N);
12054 Set_Full_View (Prev, Id);
12055 Set_Etype (Id, Any_Type);
12057 -- If so, process the full constant declaration
12060 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
12061 -- the deferred declaration is constrained, then the subtype defined
12062 -- by the subtype_indication in the full declaration shall match it
12065 Check_Possible_Deferred_Completion
12067 Prev_Obj_Def => Object_Definition (Parent (Prev)),
12068 Curr_Obj_Def => Obj_Def);
12070 Set_Full_View (Prev, Id);
12071 Set_Is_Public (Id, Is_Public (Prev));
12072 Set_Is_Internal (Id);
12073 Append_Entity (Id, Current_Scope);
12075 -- Check ALIASED present if present before (RM 7.4(7))
12077 if Is_Aliased (Prev)
12078 and then not Aliased_Present (N)
12080 Error_Msg_Sloc := Sloc (Prev);
12081 Error_Msg_N ("ALIASED required (see declaration #)", N);
12084 -- Check that placement is in private part and that the incomplete
12085 -- declaration appeared in the visible part.
12087 if Ekind (Current_Scope) = E_Package
12088 and then not In_Private_Part (Current_Scope)
12090 Error_Msg_Sloc := Sloc (Prev);
12092 ("full constant for declaration # must be in private part", N);
12094 elsif Ekind (Current_Scope) = E_Package
12096 List_Containing (Parent (Prev)) /=
12097 Visible_Declarations (Package_Specification (Current_Scope))
12100 ("deferred constant must be declared in visible part",
12104 if Is_Access_Type (T)
12105 and then Nkind (Expression (N)) = N_Allocator
12107 Check_Recursive_Declaration (Designated_Type (T));
12110 -- A deferred constant is a visible entity. If type has invariants,
12111 -- verify that the initial value satisfies them.
12113 if Has_Invariants (T) and then Present (Invariant_Procedure (T)) then
12115 Make_Invariant_Call (New_Occurrence_Of (Prev, Sloc (N))));
12118 end Constant_Redeclaration;
12120 ----------------------
12121 -- Constrain_Access --
12122 ----------------------
12124 procedure Constrain_Access
12125 (Def_Id : in out Entity_Id;
12127 Related_Nod : Node_Id)
12129 T : constant Entity_Id := Entity (Subtype_Mark (S));
12130 Desig_Type : constant Entity_Id := Designated_Type (T);
12131 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
12132 Constraint_OK : Boolean := True;
12135 if Is_Array_Type (Desig_Type) then
12136 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
12138 elsif (Is_Record_Type (Desig_Type)
12139 or else Is_Incomplete_Or_Private_Type (Desig_Type))
12140 and then not Is_Constrained (Desig_Type)
12142 -- ??? The following code is a temporary bypass to ignore a
12143 -- discriminant constraint on access type if it is constraining
12144 -- the current record. Avoid creating the implicit subtype of the
12145 -- record we are currently compiling since right now, we cannot
12146 -- handle these. For now, just return the access type itself.
12148 if Desig_Type = Current_Scope
12149 and then No (Def_Id)
12151 Set_Ekind (Desig_Subtype, E_Record_Subtype);
12152 Def_Id := Entity (Subtype_Mark (S));
12154 -- This call added to ensure that the constraint is analyzed
12155 -- (needed for a B test). Note that we still return early from
12156 -- this procedure to avoid recursive processing. ???
12158 Constrain_Discriminated_Type
12159 (Desig_Subtype, S, Related_Nod, For_Access => True);
12163 -- Enforce rule that the constraint is illegal if there is an
12164 -- unconstrained view of the designated type. This means that the
12165 -- partial view (either a private type declaration or a derivation
12166 -- from a private type) has no discriminants. (Defect Report
12167 -- 8652/0008, Technical Corrigendum 1, checked by ACATS B371001).
12169 -- Rule updated for Ada 2005: The private type is said to have
12170 -- a constrained partial view, given that objects of the type
12171 -- can be declared. Furthermore, the rule applies to all access
12172 -- types, unlike the rule concerning default discriminants (see
12175 if (Ekind (T) = E_General_Access_Type or else Ada_Version >= Ada_2005)
12176 and then Has_Private_Declaration (Desig_Type)
12177 and then In_Open_Scopes (Scope (Desig_Type))
12178 and then Has_Discriminants (Desig_Type)
12181 Pack : constant Node_Id :=
12182 Unit_Declaration_Node (Scope (Desig_Type));
12187 if Nkind (Pack) = N_Package_Declaration then
12188 Decls := Visible_Declarations (Specification (Pack));
12189 Decl := First (Decls);
12190 while Present (Decl) loop
12191 if (Nkind (Decl) = N_Private_Type_Declaration
12192 and then Chars (Defining_Identifier (Decl)) =
12193 Chars (Desig_Type))
12196 (Nkind (Decl) = N_Full_Type_Declaration
12198 Chars (Defining_Identifier (Decl)) =
12200 and then Is_Derived_Type (Desig_Type)
12202 Has_Private_Declaration (Etype (Desig_Type)))
12204 if No (Discriminant_Specifications (Decl)) then
12206 ("cannot constrain access type if designated "
12207 & "type has constrained partial view", S);
12219 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
12220 For_Access => True);
12222 elsif Is_Concurrent_Type (Desig_Type)
12223 and then not Is_Constrained (Desig_Type)
12225 Constrain_Concurrent (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
12228 Error_Msg_N ("invalid constraint on access type", S);
12230 -- We simply ignore an invalid constraint
12232 Desig_Subtype := Desig_Type;
12233 Constraint_OK := False;
12236 if No (Def_Id) then
12237 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
12239 Set_Ekind (Def_Id, E_Access_Subtype);
12242 if Constraint_OK then
12243 Set_Etype (Def_Id, Base_Type (T));
12245 if Is_Private_Type (Desig_Type) then
12246 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
12249 Set_Etype (Def_Id, Any_Type);
12252 Set_Size_Info (Def_Id, T);
12253 Set_Is_Constrained (Def_Id, Constraint_OK);
12254 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
12255 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12256 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
12258 Conditional_Delay (Def_Id, T);
12260 -- AI-363 : Subtypes of general access types whose designated types have
12261 -- default discriminants are disallowed. In instances, the rule has to
12262 -- be checked against the actual, of which T is the subtype. In a
12263 -- generic body, the rule is checked assuming that the actual type has
12264 -- defaulted discriminants.
12266 if Ada_Version >= Ada_2005 or else Warn_On_Ada_2005_Compatibility then
12267 if Ekind (Base_Type (T)) = E_General_Access_Type
12268 and then Has_Defaulted_Discriminants (Desig_Type)
12270 if Ada_Version < Ada_2005 then
12272 ("access subtype of general access type would not " &
12273 "be allowed in Ada 2005?y?", S);
12276 ("access subtype of general access type not allowed", S);
12279 Error_Msg_N ("\discriminants have defaults", S);
12281 elsif Is_Access_Type (T)
12282 and then Is_Generic_Type (Desig_Type)
12283 and then Has_Discriminants (Desig_Type)
12284 and then In_Package_Body (Current_Scope)
12286 if Ada_Version < Ada_2005 then
12288 ("access subtype would not be allowed in generic body "
12289 & "in Ada 2005?y?", S);
12292 ("access subtype not allowed in generic body", S);
12296 ("\designated type is a discriminated formal", S);
12299 end Constrain_Access;
12301 ---------------------
12302 -- Constrain_Array --
12303 ---------------------
12305 procedure Constrain_Array
12306 (Def_Id : in out Entity_Id;
12308 Related_Nod : Node_Id;
12309 Related_Id : Entity_Id;
12310 Suffix : Character)
12312 C : constant Node_Id := Constraint (SI);
12313 Number_Of_Constraints : Nat := 0;
12316 Constraint_OK : Boolean := True;
12319 T := Entity (Subtype_Mark (SI));
12321 if Is_Access_Type (T) then
12322 T := Designated_Type (T);
12325 -- If an index constraint follows a subtype mark in a subtype indication
12326 -- then the type or subtype denoted by the subtype mark must not already
12327 -- impose an index constraint. The subtype mark must denote either an
12328 -- unconstrained array type or an access type whose designated type
12329 -- is such an array type... (RM 3.6.1)
12331 if Is_Constrained (T) then
12332 Error_Msg_N ("array type is already constrained", Subtype_Mark (SI));
12333 Constraint_OK := False;
12336 S := First (Constraints (C));
12337 while Present (S) loop
12338 Number_Of_Constraints := Number_Of_Constraints + 1;
12342 -- In either case, the index constraint must provide a discrete
12343 -- range for each index of the array type and the type of each
12344 -- discrete range must be the same as that of the corresponding
12345 -- index. (RM 3.6.1)
12347 if Number_Of_Constraints /= Number_Dimensions (T) then
12348 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
12349 Constraint_OK := False;
12352 S := First (Constraints (C));
12353 Index := First_Index (T);
12356 -- Apply constraints to each index type
12358 for J in 1 .. Number_Of_Constraints loop
12359 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
12367 if No (Def_Id) then
12369 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
12370 Set_Parent (Def_Id, Related_Nod);
12373 Set_Ekind (Def_Id, E_Array_Subtype);
12376 Set_Size_Info (Def_Id, (T));
12377 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12378 Set_Etype (Def_Id, Base_Type (T));
12380 if Constraint_OK then
12381 Set_First_Index (Def_Id, First (Constraints (C)));
12383 Set_First_Index (Def_Id, First_Index (T));
12386 Set_Is_Constrained (Def_Id, True);
12387 Set_Is_Aliased (Def_Id, Is_Aliased (T));
12388 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12390 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
12391 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
12393 -- A subtype does not inherit the Packed_Array_Impl_Type of is parent.
12394 -- We need to initialize the attribute because if Def_Id is previously
12395 -- analyzed through a limited_with clause, it will have the attributes
12396 -- of an incomplete type, one of which is an Elist that overlaps the
12397 -- Packed_Array_Impl_Type field.
12399 Set_Packed_Array_Impl_Type (Def_Id, Empty);
12401 -- Build a freeze node if parent still needs one. Also make sure that
12402 -- the Depends_On_Private status is set because the subtype will need
12403 -- reprocessing at the time the base type does, and also we must set a
12404 -- conditional delay.
12406 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
12407 Conditional_Delay (Def_Id, T);
12408 end Constrain_Array;
12410 ------------------------------
12411 -- Constrain_Component_Type --
12412 ------------------------------
12414 function Constrain_Component_Type
12416 Constrained_Typ : Entity_Id;
12417 Related_Node : Node_Id;
12419 Constraints : Elist_Id) return Entity_Id
12421 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
12422 Compon_Type : constant Entity_Id := Etype (Comp);
12424 function Build_Constrained_Array_Type
12425 (Old_Type : Entity_Id) return Entity_Id;
12426 -- If Old_Type is an array type, one of whose indexes is constrained
12427 -- by a discriminant, build an Itype whose constraint replaces the
12428 -- discriminant with its value in the constraint.
12430 function Build_Constrained_Discriminated_Type
12431 (Old_Type : Entity_Id) return Entity_Id;
12432 -- Ditto for record components
12434 function Build_Constrained_Access_Type
12435 (Old_Type : Entity_Id) return Entity_Id;
12436 -- Ditto for access types. Makes use of previous two functions, to
12437 -- constrain designated type.
12439 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
12440 -- T is an array or discriminated type, C is a list of constraints
12441 -- that apply to T. This routine builds the constrained subtype.
12443 function Is_Discriminant (Expr : Node_Id) return Boolean;
12444 -- Returns True if Expr is a discriminant
12446 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
12447 -- Find the value of discriminant Discrim in Constraint
12449 -----------------------------------
12450 -- Build_Constrained_Access_Type --
12451 -----------------------------------
12453 function Build_Constrained_Access_Type
12454 (Old_Type : Entity_Id) return Entity_Id
12456 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
12458 Desig_Subtype : Entity_Id;
12462 -- if the original access type was not embedded in the enclosing
12463 -- type definition, there is no need to produce a new access
12464 -- subtype. In fact every access type with an explicit constraint
12465 -- generates an itype whose scope is the enclosing record.
12467 if not Is_Type (Scope (Old_Type)) then
12470 elsif Is_Array_Type (Desig_Type) then
12471 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
12473 elsif Has_Discriminants (Desig_Type) then
12475 -- This may be an access type to an enclosing record type for
12476 -- which we are constructing the constrained components. Return
12477 -- the enclosing record subtype. This is not always correct,
12478 -- but avoids infinite recursion. ???
12480 Desig_Subtype := Any_Type;
12482 for J in reverse 0 .. Scope_Stack.Last loop
12483 Scop := Scope_Stack.Table (J).Entity;
12486 and then Base_Type (Scop) = Base_Type (Desig_Type)
12488 Desig_Subtype := Scop;
12491 exit when not Is_Type (Scop);
12494 if Desig_Subtype = Any_Type then
12496 Build_Constrained_Discriminated_Type (Desig_Type);
12503 if Desig_Subtype /= Desig_Type then
12505 -- The Related_Node better be here or else we won't be able
12506 -- to attach new itypes to a node in the tree.
12508 pragma Assert (Present (Related_Node));
12510 Itype := Create_Itype (E_Access_Subtype, Related_Node);
12512 Set_Etype (Itype, Base_Type (Old_Type));
12513 Set_Size_Info (Itype, (Old_Type));
12514 Set_Directly_Designated_Type (Itype, Desig_Subtype);
12515 Set_Depends_On_Private (Itype, Has_Private_Component
12517 Set_Is_Access_Constant (Itype, Is_Access_Constant
12520 -- The new itype needs freezing when it depends on a not frozen
12521 -- type and the enclosing subtype needs freezing.
12523 if Has_Delayed_Freeze (Constrained_Typ)
12524 and then not Is_Frozen (Constrained_Typ)
12526 Conditional_Delay (Itype, Base_Type (Old_Type));
12534 end Build_Constrained_Access_Type;
12536 ----------------------------------
12537 -- Build_Constrained_Array_Type --
12538 ----------------------------------
12540 function Build_Constrained_Array_Type
12541 (Old_Type : Entity_Id) return Entity_Id
12545 Old_Index : Node_Id;
12546 Range_Node : Node_Id;
12547 Constr_List : List_Id;
12549 Need_To_Create_Itype : Boolean := False;
12552 Old_Index := First_Index (Old_Type);
12553 while Present (Old_Index) loop
12554 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
12556 if Is_Discriminant (Lo_Expr)
12558 Is_Discriminant (Hi_Expr)
12560 Need_To_Create_Itype := True;
12563 Next_Index (Old_Index);
12566 if Need_To_Create_Itype then
12567 Constr_List := New_List;
12569 Old_Index := First_Index (Old_Type);
12570 while Present (Old_Index) loop
12571 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
12573 if Is_Discriminant (Lo_Expr) then
12574 Lo_Expr := Get_Discr_Value (Lo_Expr);
12577 if Is_Discriminant (Hi_Expr) then
12578 Hi_Expr := Get_Discr_Value (Hi_Expr);
12583 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
12585 Append (Range_Node, To => Constr_List);
12587 Next_Index (Old_Index);
12590 return Build_Subtype (Old_Type, Constr_List);
12595 end Build_Constrained_Array_Type;
12597 ------------------------------------------
12598 -- Build_Constrained_Discriminated_Type --
12599 ------------------------------------------
12601 function Build_Constrained_Discriminated_Type
12602 (Old_Type : Entity_Id) return Entity_Id
12605 Constr_List : List_Id;
12606 Old_Constraint : Elmt_Id;
12608 Need_To_Create_Itype : Boolean := False;
12611 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
12612 while Present (Old_Constraint) loop
12613 Expr := Node (Old_Constraint);
12615 if Is_Discriminant (Expr) then
12616 Need_To_Create_Itype := True;
12619 Next_Elmt (Old_Constraint);
12622 if Need_To_Create_Itype then
12623 Constr_List := New_List;
12625 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
12626 while Present (Old_Constraint) loop
12627 Expr := Node (Old_Constraint);
12629 if Is_Discriminant (Expr) then
12630 Expr := Get_Discr_Value (Expr);
12633 Append (New_Copy_Tree (Expr), To => Constr_List);
12635 Next_Elmt (Old_Constraint);
12638 return Build_Subtype (Old_Type, Constr_List);
12643 end Build_Constrained_Discriminated_Type;
12645 -------------------
12646 -- Build_Subtype --
12647 -------------------
12649 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
12651 Subtyp_Decl : Node_Id;
12652 Def_Id : Entity_Id;
12653 Btyp : Entity_Id := Base_Type (T);
12656 -- The Related_Node better be here or else we won't be able to
12657 -- attach new itypes to a node in the tree.
12659 pragma Assert (Present (Related_Node));
12661 -- If the view of the component's type is incomplete or private
12662 -- with unknown discriminants, then the constraint must be applied
12663 -- to the full type.
12665 if Has_Unknown_Discriminants (Btyp)
12666 and then Present (Underlying_Type (Btyp))
12668 Btyp := Underlying_Type (Btyp);
12672 Make_Subtype_Indication (Loc,
12673 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
12674 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
12676 Def_Id := Create_Itype (Ekind (T), Related_Node);
12679 Make_Subtype_Declaration (Loc,
12680 Defining_Identifier => Def_Id,
12681 Subtype_Indication => Indic);
12683 Set_Parent (Subtyp_Decl, Parent (Related_Node));
12685 -- Itypes must be analyzed with checks off (see package Itypes)
12687 Analyze (Subtyp_Decl, Suppress => All_Checks);
12692 ---------------------
12693 -- Get_Discr_Value --
12694 ---------------------
12696 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
12701 -- The discriminant may be declared for the type, in which case we
12702 -- find it by iterating over the list of discriminants. If the
12703 -- discriminant is inherited from a parent type, it appears as the
12704 -- corresponding discriminant of the current type. This will be the
12705 -- case when constraining an inherited component whose constraint is
12706 -- given by a discriminant of the parent.
12708 D := First_Discriminant (Typ);
12709 E := First_Elmt (Constraints);
12711 while Present (D) loop
12712 if D = Entity (Discrim)
12713 or else D = CR_Discriminant (Entity (Discrim))
12714 or else Corresponding_Discriminant (D) = Entity (Discrim)
12719 Next_Discriminant (D);
12723 -- The Corresponding_Discriminant mechanism is incomplete, because
12724 -- the correspondence between new and old discriminants is not one
12725 -- to one: one new discriminant can constrain several old ones. In
12726 -- that case, scan sequentially the stored_constraint, the list of
12727 -- discriminants of the parents, and the constraints.
12729 -- Previous code checked for the present of the Stored_Constraint
12730 -- list for the derived type, but did not use it at all. Should it
12731 -- be present when the component is a discriminated task type?
12733 if Is_Derived_Type (Typ)
12734 and then Scope (Entity (Discrim)) = Etype (Typ)
12736 D := First_Discriminant (Etype (Typ));
12737 E := First_Elmt (Constraints);
12738 while Present (D) loop
12739 if D = Entity (Discrim) then
12743 Next_Discriminant (D);
12748 -- Something is wrong if we did not find the value
12750 raise Program_Error;
12751 end Get_Discr_Value;
12753 ---------------------
12754 -- Is_Discriminant --
12755 ---------------------
12757 function Is_Discriminant (Expr : Node_Id) return Boolean is
12758 Discrim_Scope : Entity_Id;
12761 if Denotes_Discriminant (Expr) then
12762 Discrim_Scope := Scope (Entity (Expr));
12764 -- Either we have a reference to one of Typ's discriminants,
12766 pragma Assert (Discrim_Scope = Typ
12768 -- or to the discriminants of the parent type, in the case
12769 -- of a derivation of a tagged type with variants.
12771 or else Discrim_Scope = Etype (Typ)
12772 or else Full_View (Discrim_Scope) = Etype (Typ)
12774 -- or same as above for the case where the discriminants
12775 -- were declared in Typ's private view.
12777 or else (Is_Private_Type (Discrim_Scope)
12778 and then Chars (Discrim_Scope) = Chars (Typ))
12780 -- or else we are deriving from the full view and the
12781 -- discriminant is declared in the private entity.
12783 or else (Is_Private_Type (Typ)
12784 and then Chars (Discrim_Scope) = Chars (Typ))
12786 -- Or we are constrained the corresponding record of a
12787 -- synchronized type that completes a private declaration.
12789 or else (Is_Concurrent_Record_Type (Typ)
12791 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
12793 -- or we have a class-wide type, in which case make sure the
12794 -- discriminant found belongs to the root type.
12796 or else (Is_Class_Wide_Type (Typ)
12797 and then Etype (Typ) = Discrim_Scope));
12802 -- In all other cases we have something wrong
12805 end Is_Discriminant;
12807 -- Start of processing for Constrain_Component_Type
12810 if Nkind (Parent (Comp)) = N_Component_Declaration
12811 and then Comes_From_Source (Parent (Comp))
12812 and then Comes_From_Source
12813 (Subtype_Indication (Component_Definition (Parent (Comp))))
12816 (Subtype_Indication (Component_Definition (Parent (Comp))))
12818 return Compon_Type;
12820 elsif Is_Array_Type (Compon_Type) then
12821 return Build_Constrained_Array_Type (Compon_Type);
12823 elsif Has_Discriminants (Compon_Type) then
12824 return Build_Constrained_Discriminated_Type (Compon_Type);
12826 elsif Is_Access_Type (Compon_Type) then
12827 return Build_Constrained_Access_Type (Compon_Type);
12830 return Compon_Type;
12832 end Constrain_Component_Type;
12834 --------------------------
12835 -- Constrain_Concurrent --
12836 --------------------------
12838 -- For concurrent types, the associated record value type carries the same
12839 -- discriminants, so when we constrain a concurrent type, we must constrain
12840 -- the corresponding record type as well.
12842 procedure Constrain_Concurrent
12843 (Def_Id : in out Entity_Id;
12845 Related_Nod : Node_Id;
12846 Related_Id : Entity_Id;
12847 Suffix : Character)
12849 -- Retrieve Base_Type to ensure getting to the concurrent type in the
12850 -- case of a private subtype (needed when only doing semantic analysis).
12852 T_Ent : Entity_Id := Base_Type (Entity (Subtype_Mark (SI)));
12856 if Is_Access_Type (T_Ent) then
12857 T_Ent := Designated_Type (T_Ent);
12860 T_Val := Corresponding_Record_Type (T_Ent);
12862 if Present (T_Val) then
12864 if No (Def_Id) then
12865 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
12867 -- Elaborate itype now, as it may be used in a subsequent
12868 -- synchronized operation in another scope.
12870 if Nkind (Related_Nod) = N_Full_Type_Declaration then
12871 Build_Itype_Reference (Def_Id, Related_Nod);
12875 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
12877 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12878 Set_Corresponding_Record_Type (Def_Id,
12879 Constrain_Corresponding_Record (Def_Id, T_Val, Related_Nod));
12882 -- If there is no associated record, expansion is disabled and this
12883 -- is a generic context. Create a subtype in any case, so that
12884 -- semantic analysis can proceed.
12886 if No (Def_Id) then
12887 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
12890 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
12892 end Constrain_Concurrent;
12894 ------------------------------------
12895 -- Constrain_Corresponding_Record --
12896 ------------------------------------
12898 function Constrain_Corresponding_Record
12899 (Prot_Subt : Entity_Id;
12900 Corr_Rec : Entity_Id;
12901 Related_Nod : Node_Id) return Entity_Id
12903 T_Sub : constant Entity_Id :=
12904 Create_Itype (E_Record_Subtype, Related_Nod, Corr_Rec, 'C');
12907 Set_Etype (T_Sub, Corr_Rec);
12908 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
12909 Set_Is_Constrained (T_Sub, True);
12910 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
12911 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
12913 if Has_Discriminants (Prot_Subt) then -- False only if errors.
12914 Set_Discriminant_Constraint
12915 (T_Sub, Discriminant_Constraint (Prot_Subt));
12916 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
12917 Create_Constrained_Components
12918 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
12921 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
12923 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
12924 Conditional_Delay (T_Sub, Corr_Rec);
12927 -- This is a component subtype: it will be frozen in the context of
12928 -- the enclosing record's init_proc, so that discriminant references
12929 -- are resolved to discriminals. (Note: we used to skip freezing
12930 -- altogether in that case, which caused errors downstream for
12931 -- components of a bit packed array type).
12933 Set_Has_Delayed_Freeze (T_Sub);
12937 end Constrain_Corresponding_Record;
12939 -----------------------
12940 -- Constrain_Decimal --
12941 -----------------------
12943 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
12944 T : constant Entity_Id := Entity (Subtype_Mark (S));
12945 C : constant Node_Id := Constraint (S);
12946 Loc : constant Source_Ptr := Sloc (C);
12947 Range_Expr : Node_Id;
12948 Digits_Expr : Node_Id;
12953 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
12955 if Nkind (C) = N_Range_Constraint then
12956 Range_Expr := Range_Expression (C);
12957 Digits_Val := Digits_Value (T);
12960 pragma Assert (Nkind (C) = N_Digits_Constraint);
12962 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
12964 Digits_Expr := Digits_Expression (C);
12965 Analyze_And_Resolve (Digits_Expr, Any_Integer);
12967 Check_Digits_Expression (Digits_Expr);
12968 Digits_Val := Expr_Value (Digits_Expr);
12970 if Digits_Val > Digits_Value (T) then
12972 ("digits expression is incompatible with subtype", C);
12973 Digits_Val := Digits_Value (T);
12976 if Present (Range_Constraint (C)) then
12977 Range_Expr := Range_Expression (Range_Constraint (C));
12979 Range_Expr := Empty;
12983 Set_Etype (Def_Id, Base_Type (T));
12984 Set_Size_Info (Def_Id, (T));
12985 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12986 Set_Delta_Value (Def_Id, Delta_Value (T));
12987 Set_Scale_Value (Def_Id, Scale_Value (T));
12988 Set_Small_Value (Def_Id, Small_Value (T));
12989 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
12990 Set_Digits_Value (Def_Id, Digits_Val);
12992 -- Manufacture range from given digits value if no range present
12994 if No (Range_Expr) then
12995 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
12999 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
13001 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
13004 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
13005 Set_Discrete_RM_Size (Def_Id);
13007 -- Unconditionally delay the freeze, since we cannot set size
13008 -- information in all cases correctly until the freeze point.
13010 Set_Has_Delayed_Freeze (Def_Id);
13011 end Constrain_Decimal;
13013 ----------------------------------
13014 -- Constrain_Discriminated_Type --
13015 ----------------------------------
13017 procedure Constrain_Discriminated_Type
13018 (Def_Id : Entity_Id;
13020 Related_Nod : Node_Id;
13021 For_Access : Boolean := False)
13023 E : constant Entity_Id := Entity (Subtype_Mark (S));
13026 Elist : Elist_Id := New_Elmt_List;
13028 procedure Fixup_Bad_Constraint;
13029 -- This is called after finding a bad constraint, and after having
13030 -- posted an appropriate error message. The mission is to leave the
13031 -- entity T in as reasonable state as possible.
13033 --------------------------
13034 -- Fixup_Bad_Constraint --
13035 --------------------------
13037 procedure Fixup_Bad_Constraint is
13039 -- Set a reasonable Ekind for the entity. For an incomplete type,
13040 -- we can't do much, but for other types, we can set the proper
13041 -- corresponding subtype kind.
13043 if Ekind (T) = E_Incomplete_Type then
13044 Set_Ekind (Def_Id, Ekind (T));
13046 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
13049 -- Set Etype to the known type, to reduce chances of cascaded errors
13051 Set_Etype (Def_Id, E);
13052 Set_Error_Posted (Def_Id);
13053 end Fixup_Bad_Constraint;
13055 -- Start of processing for Constrain_Discriminated_Type
13058 C := Constraint (S);
13060 -- A discriminant constraint is only allowed in a subtype indication,
13061 -- after a subtype mark. This subtype mark must denote either a type
13062 -- with discriminants, or an access type whose designated type is a
13063 -- type with discriminants. A discriminant constraint specifies the
13064 -- values of these discriminants (RM 3.7.2(5)).
13066 T := Base_Type (Entity (Subtype_Mark (S)));
13068 if Is_Access_Type (T) then
13069 T := Designated_Type (T);
13072 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal.
13073 -- Avoid generating an error for access-to-incomplete subtypes.
13075 if Ada_Version >= Ada_2005
13076 and then Ekind (T) = E_Incomplete_Type
13077 and then Nkind (Parent (S)) = N_Subtype_Declaration
13078 and then not Is_Itype (Def_Id)
13080 -- A little sanity check, emit an error message if the type
13081 -- has discriminants to begin with. Type T may be a regular
13082 -- incomplete type or imported via a limited with clause.
13084 if Has_Discriminants (T)
13085 or else (From_Limited_With (T)
13086 and then Present (Non_Limited_View (T))
13087 and then Nkind (Parent (Non_Limited_View (T))) =
13088 N_Full_Type_Declaration
13089 and then Present (Discriminant_Specifications
13090 (Parent (Non_Limited_View (T)))))
13093 ("(Ada 2005) incomplete subtype may not be constrained", C);
13095 Error_Msg_N ("invalid constraint: type has no discriminant", C);
13098 Fixup_Bad_Constraint;
13101 -- Check that the type has visible discriminants. The type may be
13102 -- a private type with unknown discriminants whose full view has
13103 -- discriminants which are invisible.
13105 elsif not Has_Discriminants (T)
13107 (Has_Unknown_Discriminants (T)
13108 and then Is_Private_Type (T))
13110 Error_Msg_N ("invalid constraint: type has no discriminant", C);
13111 Fixup_Bad_Constraint;
13114 elsif Is_Constrained (E)
13115 or else (Ekind (E) = E_Class_Wide_Subtype
13116 and then Present (Discriminant_Constraint (E)))
13118 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
13119 Fixup_Bad_Constraint;
13123 -- T may be an unconstrained subtype (e.g. a generic actual).
13124 -- Constraint applies to the base type.
13126 T := Base_Type (T);
13128 Elist := Build_Discriminant_Constraints (T, S);
13130 -- If the list returned was empty we had an error in building the
13131 -- discriminant constraint. We have also already signalled an error
13132 -- in the incomplete type case
13134 if Is_Empty_Elmt_List (Elist) then
13135 Fixup_Bad_Constraint;
13139 Build_Discriminated_Subtype (T, Def_Id, Elist, Related_Nod, For_Access);
13140 end Constrain_Discriminated_Type;
13142 ---------------------------
13143 -- Constrain_Enumeration --
13144 ---------------------------
13146 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
13147 T : constant Entity_Id := Entity (Subtype_Mark (S));
13148 C : constant Node_Id := Constraint (S);
13151 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13153 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
13155 Set_Etype (Def_Id, Base_Type (T));
13156 Set_Size_Info (Def_Id, (T));
13157 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13158 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13160 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13162 Set_Discrete_RM_Size (Def_Id);
13163 end Constrain_Enumeration;
13165 ----------------------
13166 -- Constrain_Float --
13167 ----------------------
13169 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
13170 T : constant Entity_Id := Entity (Subtype_Mark (S));
13176 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
13178 Set_Etype (Def_Id, Base_Type (T));
13179 Set_Size_Info (Def_Id, (T));
13180 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13182 -- Process the constraint
13184 C := Constraint (S);
13186 -- Digits constraint present
13188 if Nkind (C) = N_Digits_Constraint then
13190 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
13191 Check_Restriction (No_Obsolescent_Features, C);
13193 if Warn_On_Obsolescent_Feature then
13195 ("subtype digits constraint is an " &
13196 "obsolescent feature (RM J.3(8))?j?", C);
13199 D := Digits_Expression (C);
13200 Analyze_And_Resolve (D, Any_Integer);
13201 Check_Digits_Expression (D);
13202 Set_Digits_Value (Def_Id, Expr_Value (D));
13204 -- Check that digits value is in range. Obviously we can do this
13205 -- at compile time, but it is strictly a runtime check, and of
13206 -- course there is an ACVC test that checks this.
13208 if Digits_Value (Def_Id) > Digits_Value (T) then
13209 Error_Msg_Uint_1 := Digits_Value (T);
13210 Error_Msg_N ("??digits value is too large, maximum is ^", D);
13212 Make_Raise_Constraint_Error (Sloc (D),
13213 Reason => CE_Range_Check_Failed);
13214 Insert_Action (Declaration_Node (Def_Id), Rais);
13217 C := Range_Constraint (C);
13219 -- No digits constraint present
13222 Set_Digits_Value (Def_Id, Digits_Value (T));
13225 -- Range constraint present
13227 if Nkind (C) = N_Range_Constraint then
13228 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13230 -- No range constraint present
13233 pragma Assert (No (C));
13234 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13237 Set_Is_Constrained (Def_Id);
13238 end Constrain_Float;
13240 ---------------------
13241 -- Constrain_Index --
13242 ---------------------
13244 procedure Constrain_Index
13247 Related_Nod : Node_Id;
13248 Related_Id : Entity_Id;
13249 Suffix : Character;
13250 Suffix_Index : Nat)
13252 Def_Id : Entity_Id;
13253 R : Node_Id := Empty;
13254 T : constant Entity_Id := Etype (Index);
13258 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
13259 Set_Etype (Def_Id, Base_Type (T));
13261 if Nkind (S) = N_Range
13263 (Nkind (S) = N_Attribute_Reference
13264 and then Attribute_Name (S) = Name_Range)
13266 -- A Range attribute will be transformed into N_Range by Resolve
13272 Process_Range_Expr_In_Decl (R, T);
13274 if not Error_Posted (S)
13276 (Nkind (S) /= N_Range
13277 or else not Covers (T, (Etype (Low_Bound (S))))
13278 or else not Covers (T, (Etype (High_Bound (S)))))
13280 if Base_Type (T) /= Any_Type
13281 and then Etype (Low_Bound (S)) /= Any_Type
13282 and then Etype (High_Bound (S)) /= Any_Type
13284 Error_Msg_N ("range expected", S);
13288 elsif Nkind (S) = N_Subtype_Indication then
13290 -- The parser has verified that this is a discrete indication
13292 Resolve_Discrete_Subtype_Indication (S, T);
13293 Bad_Predicated_Subtype_Use
13294 ("subtype& has predicate, not allowed in index constraint",
13295 S, Entity (Subtype_Mark (S)));
13297 R := Range_Expression (Constraint (S));
13299 -- Capture values of bounds and generate temporaries for them if
13300 -- needed, since checks may cause duplication of the expressions
13301 -- which must not be reevaluated.
13303 -- The forced evaluation removes side effects from expressions, which
13304 -- should occur also in GNATprove mode. Otherwise, we end up with
13305 -- unexpected insertions of actions at places where this is not
13306 -- supposed to occur, e.g. on default parameters of a call.
13308 if Expander_Active or GNATprove_Mode then
13310 (Low_Bound (R), Related_Id => Def_Id, Is_Low_Bound => True);
13312 (High_Bound (R), Related_Id => Def_Id, Is_High_Bound => True);
13315 elsif Nkind (S) = N_Discriminant_Association then
13317 -- Syntactically valid in subtype indication
13319 Error_Msg_N ("invalid index constraint", S);
13320 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13323 -- Subtype_Mark case, no anonymous subtypes to construct
13328 if Is_Entity_Name (S) then
13329 if not Is_Type (Entity (S)) then
13330 Error_Msg_N ("expect subtype mark for index constraint", S);
13332 elsif Base_Type (Entity (S)) /= Base_Type (T) then
13333 Wrong_Type (S, Base_Type (T));
13335 -- Check error of subtype with predicate in index constraint
13338 Bad_Predicated_Subtype_Use
13339 ("subtype& has predicate, not allowed in index constraint",
13346 Error_Msg_N ("invalid index constraint", S);
13347 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13352 -- Complete construction of the Itype
13354 if Is_Modular_Integer_Type (T) then
13355 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13357 elsif Is_Integer_Type (T) then
13358 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13361 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13362 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13363 Set_First_Literal (Def_Id, First_Literal (T));
13366 Set_Size_Info (Def_Id, (T));
13367 Set_RM_Size (Def_Id, RM_Size (T));
13368 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13370 Set_Scalar_Range (Def_Id, R);
13372 Set_Etype (S, Def_Id);
13373 Set_Discrete_RM_Size (Def_Id);
13374 end Constrain_Index;
13376 -----------------------
13377 -- Constrain_Integer --
13378 -----------------------
13380 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
13381 T : constant Entity_Id := Entity (Subtype_Mark (S));
13382 C : constant Node_Id := Constraint (S);
13385 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13387 if Is_Modular_Integer_Type (T) then
13388 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13390 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13393 Set_Etype (Def_Id, Base_Type (T));
13394 Set_Size_Info (Def_Id, (T));
13395 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13396 Set_Discrete_RM_Size (Def_Id);
13397 end Constrain_Integer;
13399 ------------------------------
13400 -- Constrain_Ordinary_Fixed --
13401 ------------------------------
13403 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
13404 T : constant Entity_Id := Entity (Subtype_Mark (S));
13410 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
13411 Set_Etype (Def_Id, Base_Type (T));
13412 Set_Size_Info (Def_Id, (T));
13413 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13414 Set_Small_Value (Def_Id, Small_Value (T));
13416 -- Process the constraint
13418 C := Constraint (S);
13420 -- Delta constraint present
13422 if Nkind (C) = N_Delta_Constraint then
13424 Check_SPARK_05_Restriction ("delta constraint is not allowed", S);
13425 Check_Restriction (No_Obsolescent_Features, C);
13427 if Warn_On_Obsolescent_Feature then
13429 ("subtype delta constraint is an " &
13430 "obsolescent feature (RM J.3(7))?j?");
13433 D := Delta_Expression (C);
13434 Analyze_And_Resolve (D, Any_Real);
13435 Check_Delta_Expression (D);
13436 Set_Delta_Value (Def_Id, Expr_Value_R (D));
13438 -- Check that delta value is in range. Obviously we can do this
13439 -- at compile time, but it is strictly a runtime check, and of
13440 -- course there is an ACVC test that checks this.
13442 if Delta_Value (Def_Id) < Delta_Value (T) then
13443 Error_Msg_N ("??delta value is too small", D);
13445 Make_Raise_Constraint_Error (Sloc (D),
13446 Reason => CE_Range_Check_Failed);
13447 Insert_Action (Declaration_Node (Def_Id), Rais);
13450 C := Range_Constraint (C);
13452 -- No delta constraint present
13455 Set_Delta_Value (Def_Id, Delta_Value (T));
13458 -- Range constraint present
13460 if Nkind (C) = N_Range_Constraint then
13461 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13463 -- No range constraint present
13466 pragma Assert (No (C));
13467 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13470 Set_Discrete_RM_Size (Def_Id);
13472 -- Unconditionally delay the freeze, since we cannot set size
13473 -- information in all cases correctly until the freeze point.
13475 Set_Has_Delayed_Freeze (Def_Id);
13476 end Constrain_Ordinary_Fixed;
13478 -----------------------
13479 -- Contain_Interface --
13480 -----------------------
13482 function Contain_Interface
13483 (Iface : Entity_Id;
13484 Ifaces : Elist_Id) return Boolean
13486 Iface_Elmt : Elmt_Id;
13489 if Present (Ifaces) then
13490 Iface_Elmt := First_Elmt (Ifaces);
13491 while Present (Iface_Elmt) loop
13492 if Node (Iface_Elmt) = Iface then
13496 Next_Elmt (Iface_Elmt);
13501 end Contain_Interface;
13503 ---------------------------
13504 -- Convert_Scalar_Bounds --
13505 ---------------------------
13507 procedure Convert_Scalar_Bounds
13509 Parent_Type : Entity_Id;
13510 Derived_Type : Entity_Id;
13513 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
13520 -- Defend against previous errors
13522 if No (Scalar_Range (Derived_Type)) then
13523 Check_Error_Detected;
13527 Lo := Build_Scalar_Bound
13528 (Type_Low_Bound (Derived_Type),
13529 Parent_Type, Implicit_Base);
13531 Hi := Build_Scalar_Bound
13532 (Type_High_Bound (Derived_Type),
13533 Parent_Type, Implicit_Base);
13540 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
13542 Set_Parent (Rng, N);
13543 Set_Scalar_Range (Derived_Type, Rng);
13545 -- Analyze the bounds
13547 Analyze_And_Resolve (Lo, Implicit_Base);
13548 Analyze_And_Resolve (Hi, Implicit_Base);
13550 -- Analyze the range itself, except that we do not analyze it if
13551 -- the bounds are real literals, and we have a fixed-point type.
13552 -- The reason for this is that we delay setting the bounds in this
13553 -- case till we know the final Small and Size values (see circuit
13554 -- in Freeze.Freeze_Fixed_Point_Type for further details).
13556 if Is_Fixed_Point_Type (Parent_Type)
13557 and then Nkind (Lo) = N_Real_Literal
13558 and then Nkind (Hi) = N_Real_Literal
13562 -- Here we do the analysis of the range
13564 -- Note: we do this manually, since if we do a normal Analyze and
13565 -- Resolve call, there are problems with the conversions used for
13566 -- the derived type range.
13569 Set_Etype (Rng, Implicit_Base);
13570 Set_Analyzed (Rng, True);
13572 end Convert_Scalar_Bounds;
13574 -------------------
13575 -- Copy_And_Swap --
13576 -------------------
13578 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
13580 -- Initialize new full declaration entity by copying the pertinent
13581 -- fields of the corresponding private declaration entity.
13583 -- We temporarily set Ekind to a value appropriate for a type to
13584 -- avoid assert failures in Einfo from checking for setting type
13585 -- attributes on something that is not a type. Ekind (Priv) is an
13586 -- appropriate choice, since it allowed the attributes to be set
13587 -- in the first place. This Ekind value will be modified later.
13589 Set_Ekind (Full, Ekind (Priv));
13591 -- Also set Etype temporarily to Any_Type, again, in the absence
13592 -- of errors, it will be properly reset, and if there are errors,
13593 -- then we want a value of Any_Type to remain.
13595 Set_Etype (Full, Any_Type);
13597 -- Now start copying attributes
13599 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
13601 if Has_Discriminants (Full) then
13602 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
13603 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
13606 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
13607 Set_Homonym (Full, Homonym (Priv));
13608 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
13609 Set_Is_Public (Full, Is_Public (Priv));
13610 Set_Is_Pure (Full, Is_Pure (Priv));
13611 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
13612 Set_Has_Pragma_Unmodified (Full, Has_Pragma_Unmodified (Priv));
13613 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
13614 Set_Has_Pragma_Unreferenced_Objects
13615 (Full, Has_Pragma_Unreferenced_Objects
13618 Conditional_Delay (Full, Priv);
13620 if Is_Tagged_Type (Full) then
13621 Set_Direct_Primitive_Operations
13622 (Full, Direct_Primitive_Operations (Priv));
13623 Set_No_Tagged_Streams_Pragma
13624 (Full, No_Tagged_Streams_Pragma (Priv));
13626 if Is_Base_Type (Priv) then
13627 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
13631 Set_Is_Volatile (Full, Is_Volatile (Priv));
13632 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
13633 Set_Scope (Full, Scope (Priv));
13634 Set_Next_Entity (Full, Next_Entity (Priv));
13635 Set_First_Entity (Full, First_Entity (Priv));
13636 Set_Last_Entity (Full, Last_Entity (Priv));
13638 -- If access types have been recorded for later handling, keep them in
13639 -- the full view so that they get handled when the full view freeze
13640 -- node is expanded.
13642 if Present (Freeze_Node (Priv))
13643 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
13645 Ensure_Freeze_Node (Full);
13646 Set_Access_Types_To_Process
13647 (Freeze_Node (Full),
13648 Access_Types_To_Process (Freeze_Node (Priv)));
13651 -- Swap the two entities. Now Private is the full type entity and Full
13652 -- is the private one. They will be swapped back at the end of the
13653 -- private part. This swapping ensures that the entity that is visible
13654 -- in the private part is the full declaration.
13656 Exchange_Entities (Priv, Full);
13657 Append_Entity (Full, Scope (Full));
13660 -------------------------------------
13661 -- Copy_Array_Base_Type_Attributes --
13662 -------------------------------------
13664 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
13666 Set_Component_Alignment (T1, Component_Alignment (T2));
13667 Set_Component_Type (T1, Component_Type (T2));
13668 Set_Component_Size (T1, Component_Size (T2));
13669 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
13670 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
13671 Set_Has_Protected (T1, Has_Protected (T2));
13672 Set_Has_Task (T1, Has_Task (T2));
13673 Set_Is_Packed (T1, Is_Packed (T2));
13674 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
13675 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
13676 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
13677 end Copy_Array_Base_Type_Attributes;
13679 -----------------------------------
13680 -- Copy_Array_Subtype_Attributes --
13681 -----------------------------------
13683 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
13685 Set_Size_Info (T1, T2);
13687 Set_First_Index (T1, First_Index (T2));
13688 Set_Is_Aliased (T1, Is_Aliased (T2));
13689 Set_Is_Volatile (T1, Is_Volatile (T2));
13690 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
13691 Set_Is_Constrained (T1, Is_Constrained (T2));
13692 Set_Depends_On_Private (T1, Has_Private_Component (T2));
13693 Inherit_Rep_Item_Chain (T1, T2);
13694 Set_Convention (T1, Convention (T2));
13695 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
13696 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
13697 Set_Packed_Array_Impl_Type (T1, Packed_Array_Impl_Type (T2));
13698 end Copy_Array_Subtype_Attributes;
13700 -----------------------------------
13701 -- Create_Constrained_Components --
13702 -----------------------------------
13704 procedure Create_Constrained_Components
13706 Decl_Node : Node_Id;
13708 Constraints : Elist_Id)
13710 Loc : constant Source_Ptr := Sloc (Subt);
13711 Comp_List : constant Elist_Id := New_Elmt_List;
13712 Parent_Type : constant Entity_Id := Etype (Typ);
13713 Assoc_List : constant List_Id := New_List;
13714 Discr_Val : Elmt_Id;
13718 Is_Static : Boolean := True;
13720 procedure Collect_Fixed_Components (Typ : Entity_Id);
13721 -- Collect parent type components that do not appear in a variant part
13723 procedure Create_All_Components;
13724 -- Iterate over Comp_List to create the components of the subtype
13726 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
13727 -- Creates a new component from Old_Compon, copying all the fields from
13728 -- it, including its Etype, inserts the new component in the Subt entity
13729 -- chain and returns the new component.
13731 function Is_Variant_Record (T : Entity_Id) return Boolean;
13732 -- If true, and discriminants are static, collect only components from
13733 -- variants selected by discriminant values.
13735 ------------------------------
13736 -- Collect_Fixed_Components --
13737 ------------------------------
13739 procedure Collect_Fixed_Components (Typ : Entity_Id) is
13741 -- Build association list for discriminants, and find components of the
13742 -- variant part selected by the values of the discriminants.
13744 Old_C := First_Discriminant (Typ);
13745 Discr_Val := First_Elmt (Constraints);
13746 while Present (Old_C) loop
13747 Append_To (Assoc_List,
13748 Make_Component_Association (Loc,
13749 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
13750 Expression => New_Copy (Node (Discr_Val))));
13752 Next_Elmt (Discr_Val);
13753 Next_Discriminant (Old_C);
13756 -- The tag and the possible parent component are unconditionally in
13759 if Is_Tagged_Type (Typ) or else Has_Controlled_Component (Typ) then
13760 Old_C := First_Component (Typ);
13761 while Present (Old_C) loop
13762 if Nam_In (Chars (Old_C), Name_uTag, Name_uParent) then
13763 Append_Elmt (Old_C, Comp_List);
13766 Next_Component (Old_C);
13769 end Collect_Fixed_Components;
13771 ---------------------------
13772 -- Create_All_Components --
13773 ---------------------------
13775 procedure Create_All_Components is
13779 Comp := First_Elmt (Comp_List);
13780 while Present (Comp) loop
13781 Old_C := Node (Comp);
13782 New_C := Create_Component (Old_C);
13786 Constrain_Component_Type
13787 (Old_C, Subt, Decl_Node, Typ, Constraints));
13788 Set_Is_Public (New_C, Is_Public (Subt));
13792 end Create_All_Components;
13794 ----------------------
13795 -- Create_Component --
13796 ----------------------
13798 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
13799 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
13802 if Ekind (Old_Compon) = E_Discriminant
13803 and then Is_Completely_Hidden (Old_Compon)
13805 -- This is a shadow discriminant created for a discriminant of
13806 -- the parent type, which needs to be present in the subtype.
13807 -- Give the shadow discriminant an internal name that cannot
13808 -- conflict with that of visible components.
13810 Set_Chars (New_Compon, New_Internal_Name ('C'));
13813 -- Set the parent so we have a proper link for freezing etc. This is
13814 -- not a real parent pointer, since of course our parent does not own
13815 -- up to us and reference us, we are an illegitimate child of the
13816 -- original parent.
13818 Set_Parent (New_Compon, Parent (Old_Compon));
13820 -- If the old component's Esize was already determined and is a
13821 -- static value, then the new component simply inherits it. Otherwise
13822 -- the old component's size may require run-time determination, but
13823 -- the new component's size still might be statically determinable
13824 -- (if, for example it has a static constraint). In that case we want
13825 -- Layout_Type to recompute the component's size, so we reset its
13826 -- size and positional fields.
13828 if Frontend_Layout_On_Target
13829 and then not Known_Static_Esize (Old_Compon)
13831 Set_Esize (New_Compon, Uint_0);
13832 Init_Normalized_First_Bit (New_Compon);
13833 Init_Normalized_Position (New_Compon);
13834 Init_Normalized_Position_Max (New_Compon);
13837 -- We do not want this node marked as Comes_From_Source, since
13838 -- otherwise it would get first class status and a separate cross-
13839 -- reference line would be generated. Illegitimate children do not
13840 -- rate such recognition.
13842 Set_Comes_From_Source (New_Compon, False);
13844 -- But it is a real entity, and a birth certificate must be properly
13845 -- registered by entering it into the entity list.
13847 Enter_Name (New_Compon);
13850 end Create_Component;
13852 -----------------------
13853 -- Is_Variant_Record --
13854 -----------------------
13856 function Is_Variant_Record (T : Entity_Id) return Boolean is
13858 return Nkind (Parent (T)) = N_Full_Type_Declaration
13859 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
13860 and then Present (Component_List (Type_Definition (Parent (T))))
13863 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
13864 end Is_Variant_Record;
13866 -- Start of processing for Create_Constrained_Components
13869 pragma Assert (Subt /= Base_Type (Subt));
13870 pragma Assert (Typ = Base_Type (Typ));
13872 Set_First_Entity (Subt, Empty);
13873 Set_Last_Entity (Subt, Empty);
13875 -- Check whether constraint is fully static, in which case we can
13876 -- optimize the list of components.
13878 Discr_Val := First_Elmt (Constraints);
13879 while Present (Discr_Val) loop
13880 if not Is_OK_Static_Expression (Node (Discr_Val)) then
13881 Is_Static := False;
13885 Next_Elmt (Discr_Val);
13888 Set_Has_Static_Discriminants (Subt, Is_Static);
13892 -- Inherit the discriminants of the parent type
13894 Add_Discriminants : declare
13900 Old_C := First_Discriminant (Typ);
13902 while Present (Old_C) loop
13903 Num_Disc := Num_Disc + 1;
13904 New_C := Create_Component (Old_C);
13905 Set_Is_Public (New_C, Is_Public (Subt));
13906 Next_Discriminant (Old_C);
13909 -- For an untagged derived subtype, the number of discriminants may
13910 -- be smaller than the number of inherited discriminants, because
13911 -- several of them may be renamed by a single new discriminant or
13912 -- constrained. In this case, add the hidden discriminants back into
13913 -- the subtype, because they need to be present if the optimizer of
13914 -- the GCC 4.x back-end decides to break apart assignments between
13915 -- objects using the parent view into member-wise assignments.
13919 if Is_Derived_Type (Typ)
13920 and then not Is_Tagged_Type (Typ)
13922 Old_C := First_Stored_Discriminant (Typ);
13924 while Present (Old_C) loop
13925 Num_Gird := Num_Gird + 1;
13926 Next_Stored_Discriminant (Old_C);
13930 if Num_Gird > Num_Disc then
13932 -- Find out multiple uses of new discriminants, and add hidden
13933 -- components for the extra renamed discriminants. We recognize
13934 -- multiple uses through the Corresponding_Discriminant of a
13935 -- new discriminant: if it constrains several old discriminants,
13936 -- this field points to the last one in the parent type. The
13937 -- stored discriminants of the derived type have the same name
13938 -- as those of the parent.
13942 New_Discr : Entity_Id;
13943 Old_Discr : Entity_Id;
13946 Constr := First_Elmt (Stored_Constraint (Typ));
13947 Old_Discr := First_Stored_Discriminant (Typ);
13948 while Present (Constr) loop
13949 if Is_Entity_Name (Node (Constr))
13950 and then Ekind (Entity (Node (Constr))) = E_Discriminant
13952 New_Discr := Entity (Node (Constr));
13954 if Chars (Corresponding_Discriminant (New_Discr)) /=
13957 -- The new discriminant has been used to rename a
13958 -- subsequent old discriminant. Introduce a shadow
13959 -- component for the current old discriminant.
13961 New_C := Create_Component (Old_Discr);
13962 Set_Original_Record_Component (New_C, Old_Discr);
13966 -- The constraint has eliminated the old discriminant.
13967 -- Introduce a shadow component.
13969 New_C := Create_Component (Old_Discr);
13970 Set_Original_Record_Component (New_C, Old_Discr);
13973 Next_Elmt (Constr);
13974 Next_Stored_Discriminant (Old_Discr);
13978 end Add_Discriminants;
13981 and then Is_Variant_Record (Typ)
13983 Collect_Fixed_Components (Typ);
13985 Gather_Components (
13987 Component_List (Type_Definition (Parent (Typ))),
13988 Governed_By => Assoc_List,
13990 Report_Errors => Errors);
13991 pragma Assert (not Errors);
13993 Create_All_Components;
13995 -- If the subtype declaration is created for a tagged type derivation
13996 -- with constraints, we retrieve the record definition of the parent
13997 -- type to select the components of the proper variant.
14000 and then Is_Tagged_Type (Typ)
14001 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
14003 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
14004 and then Is_Variant_Record (Parent_Type)
14006 Collect_Fixed_Components (Typ);
14010 Component_List (Type_Definition (Parent (Parent_Type))),
14011 Governed_By => Assoc_List,
14013 Report_Errors => Errors);
14015 -- Note: previously there was a check at this point that no errors
14016 -- were detected. As a consequence of AI05-220 there may be an error
14017 -- if an inherited discriminant that controls a variant has a non-
14018 -- static constraint.
14020 -- If the tagged derivation has a type extension, collect all the
14021 -- new components therein.
14023 if Present (Record_Extension_Part (Type_Definition (Parent (Typ))))
14025 Old_C := First_Component (Typ);
14026 while Present (Old_C) loop
14027 if Original_Record_Component (Old_C) = Old_C
14028 and then Chars (Old_C) /= Name_uTag
14029 and then Chars (Old_C) /= Name_uParent
14031 Append_Elmt (Old_C, Comp_List);
14034 Next_Component (Old_C);
14038 Create_All_Components;
14041 -- If discriminants are not static, or if this is a multi-level type
14042 -- extension, we have to include all components of the parent type.
14044 Old_C := First_Component (Typ);
14045 while Present (Old_C) loop
14046 New_C := Create_Component (Old_C);
14050 Constrain_Component_Type
14051 (Old_C, Subt, Decl_Node, Typ, Constraints));
14052 Set_Is_Public (New_C, Is_Public (Subt));
14054 Next_Component (Old_C);
14059 end Create_Constrained_Components;
14061 ------------------------------------------
14062 -- Decimal_Fixed_Point_Type_Declaration --
14063 ------------------------------------------
14065 procedure Decimal_Fixed_Point_Type_Declaration
14069 Loc : constant Source_Ptr := Sloc (Def);
14070 Digs_Expr : constant Node_Id := Digits_Expression (Def);
14071 Delta_Expr : constant Node_Id := Delta_Expression (Def);
14072 Implicit_Base : Entity_Id;
14079 Check_SPARK_05_Restriction
14080 ("decimal fixed point type is not allowed", Def);
14081 Check_Restriction (No_Fixed_Point, Def);
14083 -- Create implicit base type
14086 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
14087 Set_Etype (Implicit_Base, Implicit_Base);
14089 -- Analyze and process delta expression
14091 Analyze_And_Resolve (Delta_Expr, Universal_Real);
14093 Check_Delta_Expression (Delta_Expr);
14094 Delta_Val := Expr_Value_R (Delta_Expr);
14096 -- Check delta is power of 10, and determine scale value from it
14102 Scale_Val := Uint_0;
14105 if Val < Ureal_1 then
14106 while Val < Ureal_1 loop
14107 Val := Val * Ureal_10;
14108 Scale_Val := Scale_Val + 1;
14111 if Scale_Val > 18 then
14112 Error_Msg_N ("scale exceeds maximum value of 18", Def);
14113 Scale_Val := UI_From_Int (+18);
14117 while Val > Ureal_1 loop
14118 Val := Val / Ureal_10;
14119 Scale_Val := Scale_Val - 1;
14122 if Scale_Val < -18 then
14123 Error_Msg_N ("scale is less than minimum value of -18", Def);
14124 Scale_Val := UI_From_Int (-18);
14128 if Val /= Ureal_1 then
14129 Error_Msg_N ("delta expression must be a power of 10", Def);
14130 Delta_Val := Ureal_10 ** (-Scale_Val);
14134 -- Set delta, scale and small (small = delta for decimal type)
14136 Set_Delta_Value (Implicit_Base, Delta_Val);
14137 Set_Scale_Value (Implicit_Base, Scale_Val);
14138 Set_Small_Value (Implicit_Base, Delta_Val);
14140 -- Analyze and process digits expression
14142 Analyze_And_Resolve (Digs_Expr, Any_Integer);
14143 Check_Digits_Expression (Digs_Expr);
14144 Digs_Val := Expr_Value (Digs_Expr);
14146 if Digs_Val > 18 then
14147 Digs_Val := UI_From_Int (+18);
14148 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
14151 Set_Digits_Value (Implicit_Base, Digs_Val);
14152 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
14154 -- Set range of base type from digits value for now. This will be
14155 -- expanded to represent the true underlying base range by Freeze.
14157 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
14159 -- Note: We leave size as zero for now, size will be set at freeze
14160 -- time. We have to do this for ordinary fixed-point, because the size
14161 -- depends on the specified small, and we might as well do the same for
14162 -- decimal fixed-point.
14164 pragma Assert (Esize (Implicit_Base) = Uint_0);
14166 -- If there are bounds given in the declaration use them as the
14167 -- bounds of the first named subtype.
14169 if Present (Real_Range_Specification (Def)) then
14171 RRS : constant Node_Id := Real_Range_Specification (Def);
14172 Low : constant Node_Id := Low_Bound (RRS);
14173 High : constant Node_Id := High_Bound (RRS);
14178 Analyze_And_Resolve (Low, Any_Real);
14179 Analyze_And_Resolve (High, Any_Real);
14180 Check_Real_Bound (Low);
14181 Check_Real_Bound (High);
14182 Low_Val := Expr_Value_R (Low);
14183 High_Val := Expr_Value_R (High);
14185 if Low_Val < (-Bound_Val) then
14187 ("range low bound too small for digits value", Low);
14188 Low_Val := -Bound_Val;
14191 if High_Val > Bound_Val then
14193 ("range high bound too large for digits value", High);
14194 High_Val := Bound_Val;
14197 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
14200 -- If no explicit range, use range that corresponds to given
14201 -- digits value. This will end up as the final range for the
14205 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
14208 -- Complete entity for first subtype. The inheritance of the rep item
14209 -- chain ensures that SPARK-related pragmas are not clobbered when the
14210 -- decimal fixed point type acts as a full view of a private type.
14212 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
14213 Set_Etype (T, Implicit_Base);
14214 Set_Size_Info (T, Implicit_Base);
14215 Inherit_Rep_Item_Chain (T, Implicit_Base);
14216 Set_Digits_Value (T, Digs_Val);
14217 Set_Delta_Value (T, Delta_Val);
14218 Set_Small_Value (T, Delta_Val);
14219 Set_Scale_Value (T, Scale_Val);
14220 Set_Is_Constrained (T);
14221 end Decimal_Fixed_Point_Type_Declaration;
14223 -----------------------------------
14224 -- Derive_Progenitor_Subprograms --
14225 -----------------------------------
14227 procedure Derive_Progenitor_Subprograms
14228 (Parent_Type : Entity_Id;
14229 Tagged_Type : Entity_Id)
14234 Iface_Elmt : Elmt_Id;
14235 Iface_Subp : Entity_Id;
14236 New_Subp : Entity_Id := Empty;
14237 Prim_Elmt : Elmt_Id;
14242 pragma Assert (Ada_Version >= Ada_2005
14243 and then Is_Record_Type (Tagged_Type)
14244 and then Is_Tagged_Type (Tagged_Type)
14245 and then Has_Interfaces (Tagged_Type));
14247 -- Step 1: Transfer to the full-view primitives associated with the
14248 -- partial-view that cover interface primitives. Conceptually this
14249 -- work should be done later by Process_Full_View; done here to
14250 -- simplify its implementation at later stages. It can be safely
14251 -- done here because interfaces must be visible in the partial and
14252 -- private view (RM 7.3(7.3/2)).
14254 -- Small optimization: This work is only required if the parent may
14255 -- have entities whose Alias attribute reference an interface primitive.
14256 -- Such a situation may occur if the parent is an abstract type and the
14257 -- primitive has not been yet overridden or if the parent is a generic
14258 -- formal type covering interfaces.
14260 -- If the tagged type is not abstract, it cannot have abstract
14261 -- primitives (the only entities in the list of primitives of
14262 -- non-abstract tagged types that can reference abstract primitives
14263 -- through its Alias attribute are the internal entities that have
14264 -- attribute Interface_Alias, and these entities are generated later
14265 -- by Add_Internal_Interface_Entities).
14267 if In_Private_Part (Current_Scope)
14268 and then (Is_Abstract_Type (Parent_Type)
14270 Is_Generic_Type (Parent_Type))
14272 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
14273 while Present (Elmt) loop
14274 Subp := Node (Elmt);
14276 -- At this stage it is not possible to have entities in the list
14277 -- of primitives that have attribute Interface_Alias.
14279 pragma Assert (No (Interface_Alias (Subp)));
14281 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
14283 if Is_Interface (Typ) then
14284 E := Find_Primitive_Covering_Interface
14285 (Tagged_Type => Tagged_Type,
14286 Iface_Prim => Subp);
14289 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
14291 Replace_Elmt (Elmt, E);
14292 Remove_Homonym (Subp);
14300 -- Step 2: Add primitives of progenitors that are not implemented by
14301 -- parents of Tagged_Type.
14303 if Present (Interfaces (Base_Type (Tagged_Type))) then
14304 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
14305 while Present (Iface_Elmt) loop
14306 Iface := Node (Iface_Elmt);
14308 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
14309 while Present (Prim_Elmt) loop
14310 Iface_Subp := Node (Prim_Elmt);
14312 -- Exclude derivation of predefined primitives except those
14313 -- that come from source, or are inherited from one that comes
14314 -- from source. Required to catch declarations of equality
14315 -- operators of interfaces. For example:
14317 -- type Iface is interface;
14318 -- function "=" (Left, Right : Iface) return Boolean;
14320 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
14321 or else Comes_From_Source (Ultimate_Alias (Iface_Subp))
14323 E := Find_Primitive_Covering_Interface
14324 (Tagged_Type => Tagged_Type,
14325 Iface_Prim => Iface_Subp);
14327 -- If not found we derive a new primitive leaving its alias
14328 -- attribute referencing the interface primitive.
14332 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14334 -- Ada 2012 (AI05-0197): If the covering primitive's name
14335 -- differs from the name of the interface primitive then it
14336 -- is a private primitive inherited from a parent type. In
14337 -- such case, given that Tagged_Type covers the interface,
14338 -- the inherited private primitive becomes visible. For such
14339 -- purpose we add a new entity that renames the inherited
14340 -- private primitive.
14342 elsif Chars (E) /= Chars (Iface_Subp) then
14343 pragma Assert (Has_Suffix (E, 'P'));
14345 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14346 Set_Alias (New_Subp, E);
14347 Set_Is_Abstract_Subprogram (New_Subp,
14348 Is_Abstract_Subprogram (E));
14350 -- Propagate to the full view interface entities associated
14351 -- with the partial view.
14353 elsif In_Private_Part (Current_Scope)
14354 and then Present (Alias (E))
14355 and then Alias (E) = Iface_Subp
14357 List_Containing (Parent (E)) /=
14358 Private_Declarations
14360 (Unit_Declaration_Node (Current_Scope)))
14362 Append_Elmt (E, Primitive_Operations (Tagged_Type));
14366 Next_Elmt (Prim_Elmt);
14369 Next_Elmt (Iface_Elmt);
14372 end Derive_Progenitor_Subprograms;
14374 -----------------------
14375 -- Derive_Subprogram --
14376 -----------------------
14378 procedure Derive_Subprogram
14379 (New_Subp : in out Entity_Id;
14380 Parent_Subp : Entity_Id;
14381 Derived_Type : Entity_Id;
14382 Parent_Type : Entity_Id;
14383 Actual_Subp : Entity_Id := Empty)
14385 Formal : Entity_Id;
14386 -- Formal parameter of parent primitive operation
14388 Formal_Of_Actual : Entity_Id;
14389 -- Formal parameter of actual operation, when the derivation is to
14390 -- create a renaming for a primitive operation of an actual in an
14393 New_Formal : Entity_Id;
14394 -- Formal of inherited operation
14396 Visible_Subp : Entity_Id := Parent_Subp;
14398 function Is_Private_Overriding return Boolean;
14399 -- If Subp is a private overriding of a visible operation, the inherited
14400 -- operation derives from the overridden op (even though its body is the
14401 -- overriding one) and the inherited operation is visible now. See
14402 -- sem_disp to see the full details of the handling of the overridden
14403 -- subprogram, which is removed from the list of primitive operations of
14404 -- the type. The overridden subprogram is saved locally in Visible_Subp,
14405 -- and used to diagnose abstract operations that need overriding in the
14408 procedure Replace_Type (Id, New_Id : Entity_Id);
14409 -- When the type is an anonymous access type, create a new access type
14410 -- designating the derived type.
14412 procedure Set_Derived_Name;
14413 -- This procedure sets the appropriate Chars name for New_Subp. This
14414 -- is normally just a copy of the parent name. An exception arises for
14415 -- type support subprograms, where the name is changed to reflect the
14416 -- name of the derived type, e.g. if type foo is derived from type bar,
14417 -- then a procedure barDA is derived with a name fooDA.
14419 ---------------------------
14420 -- Is_Private_Overriding --
14421 ---------------------------
14423 function Is_Private_Overriding return Boolean is
14427 -- If the parent is not a dispatching operation there is no
14428 -- need to investigate overridings
14430 if not Is_Dispatching_Operation (Parent_Subp) then
14434 -- The visible operation that is overridden is a homonym of the
14435 -- parent subprogram. We scan the homonym chain to find the one
14436 -- whose alias is the subprogram we are deriving.
14438 Prev := Current_Entity (Parent_Subp);
14439 while Present (Prev) loop
14440 if Ekind (Prev) = Ekind (Parent_Subp)
14441 and then Alias (Prev) = Parent_Subp
14442 and then Scope (Parent_Subp) = Scope (Prev)
14443 and then not Is_Hidden (Prev)
14445 Visible_Subp := Prev;
14449 Prev := Homonym (Prev);
14453 end Is_Private_Overriding;
14459 procedure Replace_Type (Id, New_Id : Entity_Id) is
14460 Id_Type : constant Entity_Id := Etype (Id);
14461 Acc_Type : Entity_Id;
14462 Par : constant Node_Id := Parent (Derived_Type);
14465 -- When the type is an anonymous access type, create a new access
14466 -- type designating the derived type. This itype must be elaborated
14467 -- at the point of the derivation, not on subsequent calls that may
14468 -- be out of the proper scope for Gigi, so we insert a reference to
14469 -- it after the derivation.
14471 if Ekind (Id_Type) = E_Anonymous_Access_Type then
14473 Desig_Typ : Entity_Id := Designated_Type (Id_Type);
14476 if Ekind (Desig_Typ) = E_Record_Type_With_Private
14477 and then Present (Full_View (Desig_Typ))
14478 and then not Is_Private_Type (Parent_Type)
14480 Desig_Typ := Full_View (Desig_Typ);
14483 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
14485 -- Ada 2005 (AI-251): Handle also derivations of abstract
14486 -- interface primitives.
14488 or else (Is_Interface (Desig_Typ)
14489 and then not Is_Class_Wide_Type (Desig_Typ))
14491 Acc_Type := New_Copy (Id_Type);
14492 Set_Etype (Acc_Type, Acc_Type);
14493 Set_Scope (Acc_Type, New_Subp);
14495 -- Set size of anonymous access type. If we have an access
14496 -- to an unconstrained array, this is a fat pointer, so it
14497 -- is sizes at twice addtress size.
14499 if Is_Array_Type (Desig_Typ)
14500 and then not Is_Constrained (Desig_Typ)
14502 Init_Size (Acc_Type, 2 * System_Address_Size);
14504 -- Other cases use a thin pointer
14507 Init_Size (Acc_Type, System_Address_Size);
14510 -- Set remaining characterstics of anonymous access type
14512 Init_Alignment (Acc_Type);
14513 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
14515 Set_Etype (New_Id, Acc_Type);
14516 Set_Scope (New_Id, New_Subp);
14518 -- Create a reference to it
14520 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
14523 Set_Etype (New_Id, Id_Type);
14527 -- In Ada2012, a formal may have an incomplete type but the type
14528 -- derivation that inherits the primitive follows the full view.
14530 elsif Base_Type (Id_Type) = Base_Type (Parent_Type)
14532 (Ekind (Id_Type) = E_Record_Type_With_Private
14533 and then Present (Full_View (Id_Type))
14535 Base_Type (Full_View (Id_Type)) = Base_Type (Parent_Type))
14537 (Ada_Version >= Ada_2012
14538 and then Ekind (Id_Type) = E_Incomplete_Type
14539 and then Full_View (Id_Type) = Parent_Type)
14541 -- Constraint checks on formals are generated during expansion,
14542 -- based on the signature of the original subprogram. The bounds
14543 -- of the derived type are not relevant, and thus we can use
14544 -- the base type for the formals. However, the return type may be
14545 -- used in a context that requires that the proper static bounds
14546 -- be used (a case statement, for example) and for those cases
14547 -- we must use the derived type (first subtype), not its base.
14549 -- If the derived_type_definition has no constraints, we know that
14550 -- the derived type has the same constraints as the first subtype
14551 -- of the parent, and we can also use it rather than its base,
14552 -- which can lead to more efficient code.
14554 if Etype (Id) = Parent_Type then
14555 if Is_Scalar_Type (Parent_Type)
14557 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
14559 Set_Etype (New_Id, Derived_Type);
14561 elsif Nkind (Par) = N_Full_Type_Declaration
14563 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
14566 (Subtype_Indication (Type_Definition (Par)))
14568 Set_Etype (New_Id, Derived_Type);
14571 Set_Etype (New_Id, Base_Type (Derived_Type));
14575 Set_Etype (New_Id, Base_Type (Derived_Type));
14579 Set_Etype (New_Id, Etype (Id));
14583 ----------------------
14584 -- Set_Derived_Name --
14585 ----------------------
14587 procedure Set_Derived_Name is
14588 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
14590 if Nm = TSS_Null then
14591 Set_Chars (New_Subp, Chars (Parent_Subp));
14593 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
14595 end Set_Derived_Name;
14597 -- Start of processing for Derive_Subprogram
14600 New_Subp := New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
14601 Set_Ekind (New_Subp, Ekind (Parent_Subp));
14603 -- Check whether the inherited subprogram is a private operation that
14604 -- should be inherited but not yet made visible. Such subprograms can
14605 -- become visible at a later point (e.g., the private part of a public
14606 -- child unit) via Declare_Inherited_Private_Subprograms. If the
14607 -- following predicate is true, then this is not such a private
14608 -- operation and the subprogram simply inherits the name of the parent
14609 -- subprogram. Note the special check for the names of controlled
14610 -- operations, which are currently exempted from being inherited with
14611 -- a hidden name because they must be findable for generation of
14612 -- implicit run-time calls.
14614 if not Is_Hidden (Parent_Subp)
14615 or else Is_Internal (Parent_Subp)
14616 or else Is_Private_Overriding
14617 or else Is_Internal_Name (Chars (Parent_Subp))
14618 or else Nam_In (Chars (Parent_Subp), Name_Initialize,
14624 -- An inherited dispatching equality will be overridden by an internally
14625 -- generated one, or by an explicit one, so preserve its name and thus
14626 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
14627 -- private operation it may become invisible if the full view has
14628 -- progenitors, and the dispatch table will be malformed.
14629 -- We check that the type is limited to handle the anomalous declaration
14630 -- of Limited_Controlled, which is derived from a non-limited type, and
14631 -- which is handled specially elsewhere as well.
14633 elsif Chars (Parent_Subp) = Name_Op_Eq
14634 and then Is_Dispatching_Operation (Parent_Subp)
14635 and then Etype (Parent_Subp) = Standard_Boolean
14636 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
14638 Etype (First_Formal (Parent_Subp)) =
14639 Etype (Next_Formal (First_Formal (Parent_Subp)))
14643 -- If parent is hidden, this can be a regular derivation if the
14644 -- parent is immediately visible in a non-instantiating context,
14645 -- or if we are in the private part of an instance. This test
14646 -- should still be refined ???
14648 -- The test for In_Instance_Not_Visible avoids inheriting the derived
14649 -- operation as a non-visible operation in cases where the parent
14650 -- subprogram might not be visible now, but was visible within the
14651 -- original generic, so it would be wrong to make the inherited
14652 -- subprogram non-visible now. (Not clear if this test is fully
14653 -- correct; are there any cases where we should declare the inherited
14654 -- operation as not visible to avoid it being overridden, e.g., when
14655 -- the parent type is a generic actual with private primitives ???)
14657 -- (they should be treated the same as other private inherited
14658 -- subprograms, but it's not clear how to do this cleanly). ???
14660 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
14661 and then Is_Immediately_Visible (Parent_Subp)
14662 and then not In_Instance)
14663 or else In_Instance_Not_Visible
14667 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
14668 -- overrides an interface primitive because interface primitives
14669 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
14671 elsif Ada_Version >= Ada_2005
14672 and then Is_Dispatching_Operation (Parent_Subp)
14673 and then Covers_Some_Interface (Parent_Subp)
14677 -- Otherwise, the type is inheriting a private operation, so enter
14678 -- it with a special name so it can't be overridden.
14681 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
14684 Set_Parent (New_Subp, Parent (Derived_Type));
14686 if Present (Actual_Subp) then
14687 Replace_Type (Actual_Subp, New_Subp);
14689 Replace_Type (Parent_Subp, New_Subp);
14692 Conditional_Delay (New_Subp, Parent_Subp);
14694 -- If we are creating a renaming for a primitive operation of an
14695 -- actual of a generic derived type, we must examine the signature
14696 -- of the actual primitive, not that of the generic formal, which for
14697 -- example may be an interface. However the name and initial value
14698 -- of the inherited operation are those of the formal primitive.
14700 Formal := First_Formal (Parent_Subp);
14702 if Present (Actual_Subp) then
14703 Formal_Of_Actual := First_Formal (Actual_Subp);
14705 Formal_Of_Actual := Empty;
14708 while Present (Formal) loop
14709 New_Formal := New_Copy (Formal);
14711 -- Normally we do not go copying parents, but in the case of
14712 -- formals, we need to link up to the declaration (which is the
14713 -- parameter specification), and it is fine to link up to the
14714 -- original formal's parameter specification in this case.
14716 Set_Parent (New_Formal, Parent (Formal));
14717 Append_Entity (New_Formal, New_Subp);
14719 if Present (Formal_Of_Actual) then
14720 Replace_Type (Formal_Of_Actual, New_Formal);
14721 Next_Formal (Formal_Of_Actual);
14723 Replace_Type (Formal, New_Formal);
14726 Next_Formal (Formal);
14729 -- If this derivation corresponds to a tagged generic actual, then
14730 -- primitive operations rename those of the actual. Otherwise the
14731 -- primitive operations rename those of the parent type, If the parent
14732 -- renames an intrinsic operator, so does the new subprogram. We except
14733 -- concatenation, which is always properly typed, and does not get
14734 -- expanded as other intrinsic operations.
14736 if No (Actual_Subp) then
14737 if Is_Intrinsic_Subprogram (Parent_Subp) then
14738 Set_Is_Intrinsic_Subprogram (New_Subp);
14740 if Present (Alias (Parent_Subp))
14741 and then Chars (Parent_Subp) /= Name_Op_Concat
14743 Set_Alias (New_Subp, Alias (Parent_Subp));
14745 Set_Alias (New_Subp, Parent_Subp);
14749 Set_Alias (New_Subp, Parent_Subp);
14753 Set_Alias (New_Subp, Actual_Subp);
14756 -- Inherit the "ghostness" from the parent subprogram
14758 if Is_Ghost_Entity (Alias (New_Subp)) then
14759 Set_Is_Ghost_Entity (New_Subp);
14762 -- Derived subprograms of a tagged type must inherit the convention
14763 -- of the parent subprogram (a requirement of AI-117). Derived
14764 -- subprograms of untagged types simply get convention Ada by default.
14766 -- If the derived type is a tagged generic formal type with unknown
14767 -- discriminants, its convention is intrinsic (RM 6.3.1 (8)).
14769 -- However, if the type is derived from a generic formal, the further
14770 -- inherited subprogram has the convention of the non-generic ancestor.
14771 -- Otherwise there would be no way to override the operation.
14772 -- (This is subject to forthcoming ARG discussions).
14774 if Is_Tagged_Type (Derived_Type) then
14775 if Is_Generic_Type (Derived_Type)
14776 and then Has_Unknown_Discriminants (Derived_Type)
14778 Set_Convention (New_Subp, Convention_Intrinsic);
14781 if Is_Generic_Type (Parent_Type)
14782 and then Has_Unknown_Discriminants (Parent_Type)
14784 Set_Convention (New_Subp, Convention (Alias (Parent_Subp)));
14786 Set_Convention (New_Subp, Convention (Parent_Subp));
14791 -- Predefined controlled operations retain their name even if the parent
14792 -- is hidden (see above), but they are not primitive operations if the
14793 -- ancestor is not visible, for example if the parent is a private
14794 -- extension completed with a controlled extension. Note that a full
14795 -- type that is controlled can break privacy: the flag Is_Controlled is
14796 -- set on both views of the type.
14798 if Is_Controlled (Parent_Type)
14799 and then Nam_In (Chars (Parent_Subp), Name_Initialize,
14802 and then Is_Hidden (Parent_Subp)
14803 and then not Is_Visibly_Controlled (Parent_Type)
14805 Set_Is_Hidden (New_Subp);
14808 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
14809 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
14811 if Ekind (Parent_Subp) = E_Procedure then
14812 Set_Is_Valued_Procedure
14813 (New_Subp, Is_Valued_Procedure (Parent_Subp));
14815 Set_Has_Controlling_Result
14816 (New_Subp, Has_Controlling_Result (Parent_Subp));
14819 -- No_Return must be inherited properly. If this is overridden in the
14820 -- case of a dispatching operation, then a check is made in Sem_Disp
14821 -- that the overriding operation is also No_Return (no such check is
14822 -- required for the case of non-dispatching operation.
14824 Set_No_Return (New_Subp, No_Return (Parent_Subp));
14826 -- A derived function with a controlling result is abstract. If the
14827 -- Derived_Type is a nonabstract formal generic derived type, then
14828 -- inherited operations are not abstract: the required check is done at
14829 -- instantiation time. If the derivation is for a generic actual, the
14830 -- function is not abstract unless the actual is.
14832 if Is_Generic_Type (Derived_Type)
14833 and then not Is_Abstract_Type (Derived_Type)
14837 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
14838 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
14840 -- A subprogram subject to pragma Extensions_Visible with value False
14841 -- requires overriding if the subprogram has at least one controlling
14842 -- OUT parameter (SPARK RM 6.1.7(6)).
14844 elsif Ada_Version >= Ada_2005
14845 and then (Is_Abstract_Subprogram (Alias (New_Subp))
14846 or else (Is_Tagged_Type (Derived_Type)
14847 and then Etype (New_Subp) = Derived_Type
14848 and then not Is_Null_Extension (Derived_Type))
14849 or else (Is_Tagged_Type (Derived_Type)
14850 and then Ekind (Etype (New_Subp)) =
14851 E_Anonymous_Access_Type
14852 and then Designated_Type (Etype (New_Subp)) =
14854 and then not Is_Null_Extension (Derived_Type))
14855 or else (Comes_From_Source (Alias (New_Subp))
14856 and then Is_EVF_Procedure (Alias (New_Subp))))
14857 and then No (Actual_Subp)
14859 if not Is_Tagged_Type (Derived_Type)
14860 or else Is_Abstract_Type (Derived_Type)
14861 or else Is_Abstract_Subprogram (Alias (New_Subp))
14863 Set_Is_Abstract_Subprogram (New_Subp);
14865 Set_Requires_Overriding (New_Subp);
14868 elsif Ada_Version < Ada_2005
14869 and then (Is_Abstract_Subprogram (Alias (New_Subp))
14870 or else (Is_Tagged_Type (Derived_Type)
14871 and then Etype (New_Subp) = Derived_Type
14872 and then No (Actual_Subp)))
14874 Set_Is_Abstract_Subprogram (New_Subp);
14876 -- AI05-0097 : an inherited operation that dispatches on result is
14877 -- abstract if the derived type is abstract, even if the parent type
14878 -- is concrete and the derived type is a null extension.
14880 elsif Has_Controlling_Result (Alias (New_Subp))
14881 and then Is_Abstract_Type (Etype (New_Subp))
14883 Set_Is_Abstract_Subprogram (New_Subp);
14885 -- Finally, if the parent type is abstract we must verify that all
14886 -- inherited operations are either non-abstract or overridden, or that
14887 -- the derived type itself is abstract (this check is performed at the
14888 -- end of a package declaration, in Check_Abstract_Overriding). A
14889 -- private overriding in the parent type will not be visible in the
14890 -- derivation if we are not in an inner package or in a child unit of
14891 -- the parent type, in which case the abstractness of the inherited
14892 -- operation is carried to the new subprogram.
14894 elsif Is_Abstract_Type (Parent_Type)
14895 and then not In_Open_Scopes (Scope (Parent_Type))
14896 and then Is_Private_Overriding
14897 and then Is_Abstract_Subprogram (Visible_Subp)
14899 if No (Actual_Subp) then
14900 Set_Alias (New_Subp, Visible_Subp);
14901 Set_Is_Abstract_Subprogram (New_Subp, True);
14904 -- If this is a derivation for an instance of a formal derived
14905 -- type, abstractness comes from the primitive operation of the
14906 -- actual, not from the operation inherited from the ancestor.
14908 Set_Is_Abstract_Subprogram
14909 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
14913 New_Overloaded_Entity (New_Subp, Derived_Type);
14915 -- Check for case of a derived subprogram for the instantiation of a
14916 -- formal derived tagged type, if so mark the subprogram as dispatching
14917 -- and inherit the dispatching attributes of the actual subprogram. The
14918 -- derived subprogram is effectively renaming of the actual subprogram,
14919 -- so it needs to have the same attributes as the actual.
14921 if Present (Actual_Subp)
14922 and then Is_Dispatching_Operation (Actual_Subp)
14924 Set_Is_Dispatching_Operation (New_Subp);
14926 if Present (DTC_Entity (Actual_Subp)) then
14927 Set_DTC_Entity (New_Subp, DTC_Entity (Actual_Subp));
14928 Set_DT_Position_Value (New_Subp, DT_Position (Actual_Subp));
14932 -- Indicate that a derived subprogram does not require a body and that
14933 -- it does not require processing of default expressions.
14935 Set_Has_Completion (New_Subp);
14936 Set_Default_Expressions_Processed (New_Subp);
14938 if Ekind (New_Subp) = E_Function then
14939 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
14941 end Derive_Subprogram;
14943 ------------------------
14944 -- Derive_Subprograms --
14945 ------------------------
14947 procedure Derive_Subprograms
14948 (Parent_Type : Entity_Id;
14949 Derived_Type : Entity_Id;
14950 Generic_Actual : Entity_Id := Empty)
14952 Op_List : constant Elist_Id :=
14953 Collect_Primitive_Operations (Parent_Type);
14955 function Check_Derived_Type return Boolean;
14956 -- Check that all the entities derived from Parent_Type are found in
14957 -- the list of primitives of Derived_Type exactly in the same order.
14959 procedure Derive_Interface_Subprogram
14960 (New_Subp : in out Entity_Id;
14962 Actual_Subp : Entity_Id);
14963 -- Derive New_Subp from the ultimate alias of the parent subprogram Subp
14964 -- (which is an interface primitive). If Generic_Actual is present then
14965 -- Actual_Subp is the actual subprogram corresponding with the generic
14966 -- subprogram Subp.
14968 function Check_Derived_Type return Boolean is
14972 New_Subp : Entity_Id;
14977 -- Traverse list of entities in the current scope searching for
14978 -- an incomplete type whose full-view is derived type
14980 E := First_Entity (Scope (Derived_Type));
14981 while Present (E) and then E /= Derived_Type loop
14982 if Ekind (E) = E_Incomplete_Type
14983 and then Present (Full_View (E))
14984 and then Full_View (E) = Derived_Type
14986 -- Disable this test if Derived_Type completes an incomplete
14987 -- type because in such case more primitives can be added
14988 -- later to the list of primitives of Derived_Type by routine
14989 -- Process_Incomplete_Dependents
14994 E := Next_Entity (E);
14997 List := Collect_Primitive_Operations (Derived_Type);
14998 Elmt := First_Elmt (List);
15000 Op_Elmt := First_Elmt (Op_List);
15001 while Present (Op_Elmt) loop
15002 Subp := Node (Op_Elmt);
15003 New_Subp := Node (Elmt);
15005 -- At this early stage Derived_Type has no entities with attribute
15006 -- Interface_Alias. In addition, such primitives are always
15007 -- located at the end of the list of primitives of Parent_Type.
15008 -- Therefore, if found we can safely stop processing pending
15011 exit when Present (Interface_Alias (Subp));
15013 -- Handle hidden entities
15015 if not Is_Predefined_Dispatching_Operation (Subp)
15016 and then Is_Hidden (Subp)
15018 if Present (New_Subp)
15019 and then Primitive_Names_Match (Subp, New_Subp)
15025 if not Present (New_Subp)
15026 or else Ekind (Subp) /= Ekind (New_Subp)
15027 or else not Primitive_Names_Match (Subp, New_Subp)
15035 Next_Elmt (Op_Elmt);
15039 end Check_Derived_Type;
15041 ---------------------------------
15042 -- Derive_Interface_Subprogram --
15043 ---------------------------------
15045 procedure Derive_Interface_Subprogram
15046 (New_Subp : in out Entity_Id;
15048 Actual_Subp : Entity_Id)
15050 Iface_Subp : constant Entity_Id := Ultimate_Alias (Subp);
15051 Iface_Type : constant Entity_Id := Find_Dispatching_Type (Iface_Subp);
15054 pragma Assert (Is_Interface (Iface_Type));
15057 (New_Subp => New_Subp,
15058 Parent_Subp => Iface_Subp,
15059 Derived_Type => Derived_Type,
15060 Parent_Type => Iface_Type,
15061 Actual_Subp => Actual_Subp);
15063 -- Given that this new interface entity corresponds with a primitive
15064 -- of the parent that was not overridden we must leave it associated
15065 -- with its parent primitive to ensure that it will share the same
15066 -- dispatch table slot when overridden. We must set the Alias to Subp
15067 -- (instead of Iface_Subp), and we must fix Is_Abstract_Subprogram
15068 -- (in case we inherited Subp from Iface_Type via a nonabstract
15069 -- generic formal type).
15071 if No (Actual_Subp) then
15072 Set_Alias (New_Subp, Subp);
15075 T : Entity_Id := Find_Dispatching_Type (Subp);
15077 while Etype (T) /= T loop
15078 if Is_Generic_Type (T) and then not Is_Abstract_Type (T) then
15079 Set_Is_Abstract_Subprogram (New_Subp, False);
15087 -- For instantiations this is not needed since the previous call to
15088 -- Derive_Subprogram leaves the entity well decorated.
15091 pragma Assert (Alias (New_Subp) = Actual_Subp);
15094 end Derive_Interface_Subprogram;
15098 Alias_Subp : Entity_Id;
15099 Act_List : Elist_Id;
15100 Act_Elmt : Elmt_Id;
15101 Act_Subp : Entity_Id := Empty;
15103 Need_Search : Boolean := False;
15104 New_Subp : Entity_Id := Empty;
15105 Parent_Base : Entity_Id;
15108 -- Start of processing for Derive_Subprograms
15111 if Ekind (Parent_Type) = E_Record_Type_With_Private
15112 and then Has_Discriminants (Parent_Type)
15113 and then Present (Full_View (Parent_Type))
15115 Parent_Base := Full_View (Parent_Type);
15117 Parent_Base := Parent_Type;
15120 if Present (Generic_Actual) then
15121 Act_List := Collect_Primitive_Operations (Generic_Actual);
15122 Act_Elmt := First_Elmt (Act_List);
15124 Act_List := No_Elist;
15125 Act_Elmt := No_Elmt;
15128 -- Derive primitives inherited from the parent. Note that if the generic
15129 -- actual is present, this is not really a type derivation, it is a
15130 -- completion within an instance.
15132 -- Case 1: Derived_Type does not implement interfaces
15134 if not Is_Tagged_Type (Derived_Type)
15135 or else (not Has_Interfaces (Derived_Type)
15136 and then not (Present (Generic_Actual)
15137 and then Has_Interfaces (Generic_Actual)))
15139 Elmt := First_Elmt (Op_List);
15140 while Present (Elmt) loop
15141 Subp := Node (Elmt);
15143 -- Literals are derived earlier in the process of building the
15144 -- derived type, and are skipped here.
15146 if Ekind (Subp) = E_Enumeration_Literal then
15149 -- The actual is a direct descendant and the common primitive
15150 -- operations appear in the same order.
15152 -- If the generic parent type is present, the derived type is an
15153 -- instance of a formal derived type, and within the instance its
15154 -- operations are those of the actual. We derive from the formal
15155 -- type but make the inherited operations aliases of the
15156 -- corresponding operations of the actual.
15159 pragma Assert (No (Node (Act_Elmt))
15160 or else (Primitive_Names_Match (Subp, Node (Act_Elmt))
15163 (Subp, Node (Act_Elmt),
15164 Skip_Controlling_Formals => True)));
15167 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
15169 if Present (Act_Elmt) then
15170 Next_Elmt (Act_Elmt);
15177 -- Case 2: Derived_Type implements interfaces
15180 -- If the parent type has no predefined primitives we remove
15181 -- predefined primitives from the list of primitives of generic
15182 -- actual to simplify the complexity of this algorithm.
15184 if Present (Generic_Actual) then
15186 Has_Predefined_Primitives : Boolean := False;
15189 -- Check if the parent type has predefined primitives
15191 Elmt := First_Elmt (Op_List);
15192 while Present (Elmt) loop
15193 Subp := Node (Elmt);
15195 if Is_Predefined_Dispatching_Operation (Subp)
15196 and then not Comes_From_Source (Ultimate_Alias (Subp))
15198 Has_Predefined_Primitives := True;
15205 -- Remove predefined primitives of Generic_Actual. We must use
15206 -- an auxiliary list because in case of tagged types the value
15207 -- returned by Collect_Primitive_Operations is the value stored
15208 -- in its Primitive_Operations attribute (and we don't want to
15209 -- modify its current contents).
15211 if not Has_Predefined_Primitives then
15213 Aux_List : constant Elist_Id := New_Elmt_List;
15216 Elmt := First_Elmt (Act_List);
15217 while Present (Elmt) loop
15218 Subp := Node (Elmt);
15220 if not Is_Predefined_Dispatching_Operation (Subp)
15221 or else Comes_From_Source (Subp)
15223 Append_Elmt (Subp, Aux_List);
15229 Act_List := Aux_List;
15233 Act_Elmt := First_Elmt (Act_List);
15234 Act_Subp := Node (Act_Elmt);
15238 -- Stage 1: If the generic actual is not present we derive the
15239 -- primitives inherited from the parent type. If the generic parent
15240 -- type is present, the derived type is an instance of a formal
15241 -- derived type, and within the instance its operations are those of
15242 -- the actual. We derive from the formal type but make the inherited
15243 -- operations aliases of the corresponding operations of the actual.
15245 Elmt := First_Elmt (Op_List);
15246 while Present (Elmt) loop
15247 Subp := Node (Elmt);
15248 Alias_Subp := Ultimate_Alias (Subp);
15250 -- Do not derive internal entities of the parent that link
15251 -- interface primitives with their covering primitive. These
15252 -- entities will be added to this type when frozen.
15254 if Present (Interface_Alias (Subp)) then
15258 -- If the generic actual is present find the corresponding
15259 -- operation in the generic actual. If the parent type is a
15260 -- direct ancestor of the derived type then, even if it is an
15261 -- interface, the operations are inherited from the primary
15262 -- dispatch table and are in the proper order. If we detect here
15263 -- that primitives are not in the same order we traverse the list
15264 -- of primitive operations of the actual to find the one that
15265 -- implements the interface primitive.
15269 (Present (Generic_Actual)
15270 and then Present (Act_Subp)
15272 (Primitive_Names_Match (Subp, Act_Subp)
15274 Type_Conformant (Subp, Act_Subp,
15275 Skip_Controlling_Formals => True)))
15277 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual,
15278 Use_Full_View => True));
15280 -- Remember that we need searching for all pending primitives
15282 Need_Search := True;
15284 -- Handle entities associated with interface primitives
15286 if Present (Alias_Subp)
15287 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
15288 and then not Is_Predefined_Dispatching_Operation (Subp)
15290 -- Search for the primitive in the homonym chain
15293 Find_Primitive_Covering_Interface
15294 (Tagged_Type => Generic_Actual,
15295 Iface_Prim => Alias_Subp);
15297 -- Previous search may not locate primitives covering
15298 -- interfaces defined in generics units or instantiations.
15299 -- (it fails if the covering primitive has formals whose
15300 -- type is also defined in generics or instantiations).
15301 -- In such case we search in the list of primitives of the
15302 -- generic actual for the internal entity that links the
15303 -- interface primitive and the covering primitive.
15306 and then Is_Generic_Type (Parent_Type)
15308 -- This code has been designed to handle only generic
15309 -- formals that implement interfaces that are defined
15310 -- in a generic unit or instantiation. If this code is
15311 -- needed for other cases we must review it because
15312 -- (given that it relies on Original_Location to locate
15313 -- the primitive of Generic_Actual that covers the
15314 -- interface) it could leave linked through attribute
15315 -- Alias entities of unrelated instantiations).
15319 (Scope (Find_Dispatching_Type (Alias_Subp)))
15321 Instantiation_Depth
15322 (Sloc (Find_Dispatching_Type (Alias_Subp))) > 0);
15325 Iface_Prim_Loc : constant Source_Ptr :=
15326 Original_Location (Sloc (Alias_Subp));
15333 First_Elmt (Primitive_Operations (Generic_Actual));
15335 Search : while Present (Elmt) loop
15336 Prim := Node (Elmt);
15338 if Present (Interface_Alias (Prim))
15339 and then Original_Location
15340 (Sloc (Interface_Alias (Prim))) =
15343 Act_Subp := Alias (Prim);
15352 pragma Assert (Present (Act_Subp)
15353 or else Is_Abstract_Type (Generic_Actual)
15354 or else Serious_Errors_Detected > 0);
15356 -- Handle predefined primitives plus the rest of user-defined
15360 Act_Elmt := First_Elmt (Act_List);
15361 while Present (Act_Elmt) loop
15362 Act_Subp := Node (Act_Elmt);
15364 exit when Primitive_Names_Match (Subp, Act_Subp)
15365 and then Type_Conformant
15367 Skip_Controlling_Formals => True)
15368 and then No (Interface_Alias (Act_Subp));
15370 Next_Elmt (Act_Elmt);
15373 if No (Act_Elmt) then
15379 -- Case 1: If the parent is a limited interface then it has the
15380 -- predefined primitives of synchronized interfaces. However, the
15381 -- actual type may be a non-limited type and hence it does not
15382 -- have such primitives.
15384 if Present (Generic_Actual)
15385 and then not Present (Act_Subp)
15386 and then Is_Limited_Interface (Parent_Base)
15387 and then Is_Predefined_Interface_Primitive (Subp)
15391 -- Case 2: Inherit entities associated with interfaces that were
15392 -- not covered by the parent type. We exclude here null interface
15393 -- primitives because they do not need special management.
15395 -- We also exclude interface operations that are renamings. If the
15396 -- subprogram is an explicit renaming of an interface primitive,
15397 -- it is a regular primitive operation, and the presence of its
15398 -- alias is not relevant: it has to be derived like any other
15401 elsif Present (Alias (Subp))
15402 and then Nkind (Unit_Declaration_Node (Subp)) /=
15403 N_Subprogram_Renaming_Declaration
15404 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
15406 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
15407 and then Null_Present (Parent (Alias_Subp)))
15409 -- If this is an abstract private type then we transfer the
15410 -- derivation of the interface primitive from the partial view
15411 -- to the full view. This is safe because all the interfaces
15412 -- must be visible in the partial view. Done to avoid adding
15413 -- a new interface derivation to the private part of the
15414 -- enclosing package; otherwise this new derivation would be
15415 -- decorated as hidden when the analysis of the enclosing
15416 -- package completes.
15418 if Is_Abstract_Type (Derived_Type)
15419 and then In_Private_Part (Current_Scope)
15420 and then Has_Private_Declaration (Derived_Type)
15423 Partial_View : Entity_Id;
15428 Partial_View := First_Entity (Current_Scope);
15430 exit when No (Partial_View)
15431 or else (Has_Private_Declaration (Partial_View)
15433 Full_View (Partial_View) = Derived_Type);
15435 Next_Entity (Partial_View);
15438 -- If the partial view was not found then the source code
15439 -- has errors and the derivation is not needed.
15441 if Present (Partial_View) then
15443 First_Elmt (Primitive_Operations (Partial_View));
15444 while Present (Elmt) loop
15445 Ent := Node (Elmt);
15447 if Present (Alias (Ent))
15448 and then Ultimate_Alias (Ent) = Alias (Subp)
15451 (Ent, Primitive_Operations (Derived_Type));
15458 -- If the interface primitive was not found in the
15459 -- partial view then this interface primitive was
15460 -- overridden. We add a derivation to activate in
15461 -- Derive_Progenitor_Subprograms the machinery to
15465 Derive_Interface_Subprogram
15466 (New_Subp => New_Subp,
15468 Actual_Subp => Act_Subp);
15473 Derive_Interface_Subprogram
15474 (New_Subp => New_Subp,
15476 Actual_Subp => Act_Subp);
15479 -- Case 3: Common derivation
15483 (New_Subp => New_Subp,
15484 Parent_Subp => Subp,
15485 Derived_Type => Derived_Type,
15486 Parent_Type => Parent_Base,
15487 Actual_Subp => Act_Subp);
15490 -- No need to update Act_Elm if we must search for the
15491 -- corresponding operation in the generic actual
15494 and then Present (Act_Elmt)
15496 Next_Elmt (Act_Elmt);
15497 Act_Subp := Node (Act_Elmt);
15504 -- Inherit additional operations from progenitors. If the derived
15505 -- type is a generic actual, there are not new primitive operations
15506 -- for the type because it has those of the actual, and therefore
15507 -- nothing needs to be done. The renamings generated above are not
15508 -- primitive operations, and their purpose is simply to make the
15509 -- proper operations visible within an instantiation.
15511 if No (Generic_Actual) then
15512 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
15516 -- Final check: Direct descendants must have their primitives in the
15517 -- same order. We exclude from this test untagged types and instances
15518 -- of formal derived types. We skip this test if we have already
15519 -- reported serious errors in the sources.
15521 pragma Assert (not Is_Tagged_Type (Derived_Type)
15522 or else Present (Generic_Actual)
15523 or else Serious_Errors_Detected > 0
15524 or else Check_Derived_Type);
15525 end Derive_Subprograms;
15527 --------------------------------
15528 -- Derived_Standard_Character --
15529 --------------------------------
15531 procedure Derived_Standard_Character
15533 Parent_Type : Entity_Id;
15534 Derived_Type : Entity_Id)
15536 Loc : constant Source_Ptr := Sloc (N);
15537 Def : constant Node_Id := Type_Definition (N);
15538 Indic : constant Node_Id := Subtype_Indication (Def);
15539 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
15540 Implicit_Base : constant Entity_Id :=
15542 (E_Enumeration_Type, N, Derived_Type, 'B');
15548 Discard_Node (Process_Subtype (Indic, N));
15550 Set_Etype (Implicit_Base, Parent_Base);
15551 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
15552 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
15554 Set_Is_Character_Type (Implicit_Base, True);
15555 Set_Has_Delayed_Freeze (Implicit_Base);
15557 -- The bounds of the implicit base are the bounds of the parent base.
15558 -- Note that their type is the parent base.
15560 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
15561 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
15563 Set_Scalar_Range (Implicit_Base,
15566 High_Bound => Hi));
15568 Conditional_Delay (Derived_Type, Parent_Type);
15570 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
15571 Set_Etype (Derived_Type, Implicit_Base);
15572 Set_Size_Info (Derived_Type, Parent_Type);
15574 if Unknown_RM_Size (Derived_Type) then
15575 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
15578 Set_Is_Character_Type (Derived_Type, True);
15580 if Nkind (Indic) /= N_Subtype_Indication then
15582 -- If no explicit constraint, the bounds are those
15583 -- of the parent type.
15585 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
15586 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
15587 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
15590 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
15592 -- Because the implicit base is used in the conversion of the bounds, we
15593 -- have to freeze it now. This is similar to what is done for numeric
15594 -- types, and it equally suspicious, but otherwise a non-static bound
15595 -- will have a reference to an unfrozen type, which is rejected by Gigi
15596 -- (???). This requires specific care for definition of stream
15597 -- attributes. For details, see comments at the end of
15598 -- Build_Derived_Numeric_Type.
15600 Freeze_Before (N, Implicit_Base);
15601 end Derived_Standard_Character;
15603 ------------------------------
15604 -- Derived_Type_Declaration --
15605 ------------------------------
15607 procedure Derived_Type_Declaration
15610 Is_Completion : Boolean)
15612 Parent_Type : Entity_Id;
15614 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
15615 -- Check whether the parent type is a generic formal, or derives
15616 -- directly or indirectly from one.
15618 ------------------------
15619 -- Comes_From_Generic --
15620 ------------------------
15622 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
15624 if Is_Generic_Type (Typ) then
15627 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
15630 elsif Is_Private_Type (Typ)
15631 and then Present (Full_View (Typ))
15632 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
15636 elsif Is_Generic_Actual_Type (Typ) then
15642 end Comes_From_Generic;
15646 Def : constant Node_Id := Type_Definition (N);
15647 Iface_Def : Node_Id;
15648 Indic : constant Node_Id := Subtype_Indication (Def);
15649 Extension : constant Node_Id := Record_Extension_Part (Def);
15650 Parent_Node : Node_Id;
15653 -- Start of processing for Derived_Type_Declaration
15656 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
15658 -- Ada 2005 (AI-251): In case of interface derivation check that the
15659 -- parent is also an interface.
15661 if Interface_Present (Def) then
15662 Check_SPARK_05_Restriction ("interface is not allowed", Def);
15664 if not Is_Interface (Parent_Type) then
15665 Diagnose_Interface (Indic, Parent_Type);
15668 Parent_Node := Parent (Base_Type (Parent_Type));
15669 Iface_Def := Type_Definition (Parent_Node);
15671 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
15672 -- other limited interfaces.
15674 if Limited_Present (Def) then
15675 if Limited_Present (Iface_Def) then
15678 elsif Protected_Present (Iface_Def) then
15680 ("descendant of & must be declared as a protected "
15681 & "interface", N, Parent_Type);
15683 elsif Synchronized_Present (Iface_Def) then
15685 ("descendant of & must be declared as a synchronized "
15686 & "interface", N, Parent_Type);
15688 elsif Task_Present (Iface_Def) then
15690 ("descendant of & must be declared as a task interface",
15695 ("(Ada 2005) limited interface cannot inherit from "
15696 & "non-limited interface", Indic);
15699 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
15700 -- from non-limited or limited interfaces.
15702 elsif not Protected_Present (Def)
15703 and then not Synchronized_Present (Def)
15704 and then not Task_Present (Def)
15706 if Limited_Present (Iface_Def) then
15709 elsif Protected_Present (Iface_Def) then
15711 ("descendant of & must be declared as a protected "
15712 & "interface", N, Parent_Type);
15714 elsif Synchronized_Present (Iface_Def) then
15716 ("descendant of & must be declared as a synchronized "
15717 & "interface", N, Parent_Type);
15719 elsif Task_Present (Iface_Def) then
15721 ("descendant of & must be declared as a task interface",
15730 if Is_Tagged_Type (Parent_Type)
15731 and then Is_Concurrent_Type (Parent_Type)
15732 and then not Is_Interface (Parent_Type)
15735 ("parent type of a record extension cannot be a synchronized "
15736 & "tagged type (RM 3.9.1 (3/1))", N);
15737 Set_Etype (T, Any_Type);
15741 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
15744 if Is_Tagged_Type (Parent_Type)
15745 and then Is_Non_Empty_List (Interface_List (Def))
15752 Intf := First (Interface_List (Def));
15753 while Present (Intf) loop
15754 T := Find_Type_Of_Subtype_Indic (Intf);
15756 if not Is_Interface (T) then
15757 Diagnose_Interface (Intf, T);
15759 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
15760 -- a limited type from having a nonlimited progenitor.
15762 elsif (Limited_Present (Def)
15763 or else (not Is_Interface (Parent_Type)
15764 and then Is_Limited_Type (Parent_Type)))
15765 and then not Is_Limited_Interface (T)
15768 ("progenitor interface& of limited type must be limited",
15777 if Parent_Type = Any_Type
15778 or else Etype (Parent_Type) = Any_Type
15779 or else (Is_Class_Wide_Type (Parent_Type)
15780 and then Etype (Parent_Type) = T)
15782 -- If Parent_Type is undefined or illegal, make new type into a
15783 -- subtype of Any_Type, and set a few attributes to prevent cascaded
15784 -- errors. If this is a self-definition, emit error now.
15786 if T = Parent_Type or else T = Etype (Parent_Type) then
15787 Error_Msg_N ("type cannot be used in its own definition", Indic);
15790 Set_Ekind (T, Ekind (Parent_Type));
15791 Set_Etype (T, Any_Type);
15792 Set_Scalar_Range (T, Scalar_Range (Any_Type));
15794 if Is_Tagged_Type (T)
15795 and then Is_Record_Type (T)
15797 Set_Direct_Primitive_Operations (T, New_Elmt_List);
15803 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
15804 -- an interface is special because the list of interfaces in the full
15805 -- view can be given in any order. For example:
15807 -- type A is interface;
15808 -- type B is interface and A;
15809 -- type D is new B with private;
15811 -- type D is new A and B with null record; -- 1 --
15813 -- In this case we perform the following transformation of -1-:
15815 -- type D is new B and A with null record;
15817 -- If the parent of the full-view covers the parent of the partial-view
15818 -- we have two possible cases:
15820 -- 1) They have the same parent
15821 -- 2) The parent of the full-view implements some further interfaces
15823 -- In both cases we do not need to perform the transformation. In the
15824 -- first case the source program is correct and the transformation is
15825 -- not needed; in the second case the source program does not fulfill
15826 -- the no-hidden interfaces rule (AI-396) and the error will be reported
15829 -- This transformation not only simplifies the rest of the analysis of
15830 -- this type declaration but also simplifies the correct generation of
15831 -- the object layout to the expander.
15833 if In_Private_Part (Current_Scope)
15834 and then Is_Interface (Parent_Type)
15838 Partial_View : Entity_Id;
15839 Partial_View_Parent : Entity_Id;
15840 New_Iface : Node_Id;
15843 -- Look for the associated private type declaration
15845 Partial_View := First_Entity (Current_Scope);
15847 exit when No (Partial_View)
15848 or else (Has_Private_Declaration (Partial_View)
15849 and then Full_View (Partial_View) = T);
15851 Next_Entity (Partial_View);
15854 -- If the partial view was not found then the source code has
15855 -- errors and the transformation is not needed.
15857 if Present (Partial_View) then
15858 Partial_View_Parent := Etype (Partial_View);
15860 -- If the parent of the full-view covers the parent of the
15861 -- partial-view we have nothing else to do.
15863 if Interface_Present_In_Ancestor
15864 (Parent_Type, Partial_View_Parent)
15868 -- Traverse the list of interfaces of the full-view to look
15869 -- for the parent of the partial-view and perform the tree
15873 Iface := First (Interface_List (Def));
15874 while Present (Iface) loop
15875 if Etype (Iface) = Etype (Partial_View) then
15876 Rewrite (Subtype_Indication (Def),
15877 New_Copy (Subtype_Indication
15878 (Parent (Partial_View))));
15881 Make_Identifier (Sloc (N), Chars (Parent_Type));
15882 Append (New_Iface, Interface_List (Def));
15884 -- Analyze the transformed code
15886 Derived_Type_Declaration (T, N, Is_Completion);
15897 -- Only composite types other than array types are allowed to have
15900 if Present (Discriminant_Specifications (N)) then
15901 if (Is_Elementary_Type (Parent_Type)
15903 Is_Array_Type (Parent_Type))
15904 and then not Error_Posted (N)
15907 ("elementary or array type cannot have discriminants",
15908 Defining_Identifier (First (Discriminant_Specifications (N))));
15909 Set_Has_Discriminants (T, False);
15911 -- The type is allowed to have discriminants
15914 Check_SPARK_05_Restriction ("discriminant type is not allowed", N);
15918 -- In Ada 83, a derived type defined in a package specification cannot
15919 -- be used for further derivation until the end of its visible part.
15920 -- Note that derivation in the private part of the package is allowed.
15922 if Ada_Version = Ada_83
15923 and then Is_Derived_Type (Parent_Type)
15924 and then In_Visible_Part (Scope (Parent_Type))
15926 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
15928 ("(Ada 83): premature use of type for derivation", Indic);
15932 -- Check for early use of incomplete or private type
15934 if Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
15935 Error_Msg_N ("premature derivation of incomplete type", Indic);
15938 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
15939 and then not Comes_From_Generic (Parent_Type))
15940 or else Has_Private_Component (Parent_Type)
15942 -- The ancestor type of a formal type can be incomplete, in which
15943 -- case only the operations of the partial view are available in the
15944 -- generic. Subsequent checks may be required when the full view is
15945 -- analyzed to verify that a derivation from a tagged type has an
15948 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
15951 elsif No (Underlying_Type (Parent_Type))
15952 or else Has_Private_Component (Parent_Type)
15955 ("premature derivation of derived or private type", Indic);
15957 -- Flag the type itself as being in error, this prevents some
15958 -- nasty problems with subsequent uses of the malformed type.
15960 Set_Error_Posted (T);
15962 -- Check that within the immediate scope of an untagged partial
15963 -- view it's illegal to derive from the partial view if the
15964 -- full view is tagged. (7.3(7))
15966 -- We verify that the Parent_Type is a partial view by checking
15967 -- that it is not a Full_Type_Declaration (i.e. a private type or
15968 -- private extension declaration), to distinguish a partial view
15969 -- from a derivation from a private type which also appears as
15970 -- E_Private_Type. If the parent base type is not declared in an
15971 -- enclosing scope there is no need to check.
15973 elsif Present (Full_View (Parent_Type))
15974 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
15975 and then not Is_Tagged_Type (Parent_Type)
15976 and then Is_Tagged_Type (Full_View (Parent_Type))
15977 and then In_Open_Scopes (Scope (Base_Type (Parent_Type)))
15980 ("premature derivation from type with tagged full view",
15985 -- Check that form of derivation is appropriate
15987 Taggd := Is_Tagged_Type (Parent_Type);
15989 -- Set the parent type to the class-wide type's specific type in this
15990 -- case to prevent cascading errors
15992 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
15993 Error_Msg_N ("parent type must not be a class-wide type", Indic);
15994 Set_Etype (T, Etype (Parent_Type));
15998 if Present (Extension) and then not Taggd then
16000 ("type derived from untagged type cannot have extension", Indic);
16002 elsif No (Extension) and then Taggd then
16004 -- If this declaration is within a private part (or body) of a
16005 -- generic instantiation then the derivation is allowed (the parent
16006 -- type can only appear tagged in this case if it's a generic actual
16007 -- type, since it would otherwise have been rejected in the analysis
16008 -- of the generic template).
16010 if not Is_Generic_Actual_Type (Parent_Type)
16011 or else In_Visible_Part (Scope (Parent_Type))
16013 if Is_Class_Wide_Type (Parent_Type) then
16015 ("parent type must not be a class-wide type", Indic);
16017 -- Use specific type to prevent cascaded errors.
16019 Parent_Type := Etype (Parent_Type);
16023 ("type derived from tagged type must have extension", Indic);
16028 -- AI-443: Synchronized formal derived types require a private
16029 -- extension. There is no point in checking the ancestor type or
16030 -- the progenitors since the construct is wrong to begin with.
16032 if Ada_Version >= Ada_2005
16033 and then Is_Generic_Type (T)
16034 and then Present (Original_Node (N))
16037 Decl : constant Node_Id := Original_Node (N);
16040 if Nkind (Decl) = N_Formal_Type_Declaration
16041 and then Nkind (Formal_Type_Definition (Decl)) =
16042 N_Formal_Derived_Type_Definition
16043 and then Synchronized_Present (Formal_Type_Definition (Decl))
16044 and then No (Extension)
16046 -- Avoid emitting a duplicate error message
16048 and then not Error_Posted (Indic)
16051 ("synchronized derived type must have extension", N);
16056 if Null_Exclusion_Present (Def)
16057 and then not Is_Access_Type (Parent_Type)
16059 Error_Msg_N ("null exclusion can only apply to an access type", N);
16062 -- Avoid deriving parent primitives of underlying record views
16064 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
16065 Derive_Subps => not Is_Underlying_Record_View (T));
16067 -- AI-419: The parent type of an explicitly limited derived type must
16068 -- be a limited type or a limited interface.
16070 if Limited_Present (Def) then
16071 Set_Is_Limited_Record (T);
16073 if Is_Interface (T) then
16074 Set_Is_Limited_Interface (T);
16077 if not Is_Limited_Type (Parent_Type)
16079 (not Is_Interface (Parent_Type)
16080 or else not Is_Limited_Interface (Parent_Type))
16082 -- AI05-0096: a derivation in the private part of an instance is
16083 -- legal if the generic formal is untagged limited, and the actual
16086 if Is_Generic_Actual_Type (Parent_Type)
16087 and then In_Private_Part (Current_Scope)
16090 (Generic_Parent_Type (Parent (Parent_Type)))
16096 ("parent type& of limited type must be limited",
16102 -- In SPARK, there are no derived type definitions other than type
16103 -- extensions of tagged record types.
16105 if No (Extension) then
16106 Check_SPARK_05_Restriction
16107 ("derived type is not allowed", Original_Node (N));
16109 end Derived_Type_Declaration;
16111 ------------------------
16112 -- Diagnose_Interface --
16113 ------------------------
16115 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
16117 if not Is_Interface (E) and then E /= Any_Type then
16118 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
16120 end Diagnose_Interface;
16122 ----------------------------------
16123 -- Enumeration_Type_Declaration --
16124 ----------------------------------
16126 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
16133 -- Create identifier node representing lower bound
16135 B_Node := New_Node (N_Identifier, Sloc (Def));
16136 L := First (Literals (Def));
16137 Set_Chars (B_Node, Chars (L));
16138 Set_Entity (B_Node, L);
16139 Set_Etype (B_Node, T);
16140 Set_Is_Static_Expression (B_Node, True);
16142 R_Node := New_Node (N_Range, Sloc (Def));
16143 Set_Low_Bound (R_Node, B_Node);
16145 Set_Ekind (T, E_Enumeration_Type);
16146 Set_First_Literal (T, L);
16148 Set_Is_Constrained (T);
16152 -- Loop through literals of enumeration type setting pos and rep values
16153 -- except that if the Ekind is already set, then it means the literal
16154 -- was already constructed (case of a derived type declaration and we
16155 -- should not disturb the Pos and Rep values.
16157 while Present (L) loop
16158 if Ekind (L) /= E_Enumeration_Literal then
16159 Set_Ekind (L, E_Enumeration_Literal);
16160 Set_Enumeration_Pos (L, Ev);
16161 Set_Enumeration_Rep (L, Ev);
16162 Set_Is_Known_Valid (L, True);
16166 New_Overloaded_Entity (L);
16167 Generate_Definition (L);
16168 Set_Convention (L, Convention_Intrinsic);
16170 -- Case of character literal
16172 if Nkind (L) = N_Defining_Character_Literal then
16173 Set_Is_Character_Type (T, True);
16175 -- Check violation of No_Wide_Characters
16177 if Restriction_Check_Required (No_Wide_Characters) then
16178 Get_Name_String (Chars (L));
16180 if Name_Len >= 3 and then Name_Buffer (1 .. 2) = "QW" then
16181 Check_Restriction (No_Wide_Characters, L);
16190 -- Now create a node representing upper bound
16192 B_Node := New_Node (N_Identifier, Sloc (Def));
16193 Set_Chars (B_Node, Chars (Last (Literals (Def))));
16194 Set_Entity (B_Node, Last (Literals (Def)));
16195 Set_Etype (B_Node, T);
16196 Set_Is_Static_Expression (B_Node, True);
16198 Set_High_Bound (R_Node, B_Node);
16200 -- Initialize various fields of the type. Some of this information
16201 -- may be overwritten later through rep.clauses.
16203 Set_Scalar_Range (T, R_Node);
16204 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
16205 Set_Enum_Esize (T);
16206 Set_Enum_Pos_To_Rep (T, Empty);
16208 -- Set Discard_Names if configuration pragma set, or if there is
16209 -- a parameterless pragma in the current declarative region
16211 if Global_Discard_Names or else Discard_Names (Scope (T)) then
16212 Set_Discard_Names (T);
16215 -- Process end label if there is one
16217 if Present (Def) then
16218 Process_End_Label (Def, 'e', T);
16220 end Enumeration_Type_Declaration;
16222 ---------------------------------
16223 -- Expand_To_Stored_Constraint --
16224 ---------------------------------
16226 function Expand_To_Stored_Constraint
16228 Constraint : Elist_Id) return Elist_Id
16230 Explicitly_Discriminated_Type : Entity_Id;
16231 Expansion : Elist_Id;
16232 Discriminant : Entity_Id;
16234 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
16235 -- Find the nearest type that actually specifies discriminants
16237 ---------------------------------
16238 -- Type_With_Explicit_Discrims --
16239 ---------------------------------
16241 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
16242 Typ : constant E := Base_Type (Id);
16245 if Ekind (Typ) in Incomplete_Or_Private_Kind then
16246 if Present (Full_View (Typ)) then
16247 return Type_With_Explicit_Discrims (Full_View (Typ));
16251 if Has_Discriminants (Typ) then
16256 if Etype (Typ) = Typ then
16258 elsif Has_Discriminants (Typ) then
16261 return Type_With_Explicit_Discrims (Etype (Typ));
16264 end Type_With_Explicit_Discrims;
16266 -- Start of processing for Expand_To_Stored_Constraint
16269 if No (Constraint) or else Is_Empty_Elmt_List (Constraint) then
16273 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
16275 if No (Explicitly_Discriminated_Type) then
16279 Expansion := New_Elmt_List;
16282 First_Stored_Discriminant (Explicitly_Discriminated_Type);
16283 while Present (Discriminant) loop
16285 (Get_Discriminant_Value
16286 (Discriminant, Explicitly_Discriminated_Type, Constraint),
16288 Next_Stored_Discriminant (Discriminant);
16292 end Expand_To_Stored_Constraint;
16294 ---------------------------
16295 -- Find_Hidden_Interface --
16296 ---------------------------
16298 function Find_Hidden_Interface
16300 Dest : Elist_Id) return Entity_Id
16303 Iface_Elmt : Elmt_Id;
16306 if Present (Src) and then Present (Dest) then
16307 Iface_Elmt := First_Elmt (Src);
16308 while Present (Iface_Elmt) loop
16309 Iface := Node (Iface_Elmt);
16311 if Is_Interface (Iface)
16312 and then not Contain_Interface (Iface, Dest)
16317 Next_Elmt (Iface_Elmt);
16322 end Find_Hidden_Interface;
16324 --------------------
16325 -- Find_Type_Name --
16326 --------------------
16328 function Find_Type_Name (N : Node_Id) return Entity_Id is
16329 Id : constant Entity_Id := Defining_Identifier (N);
16331 New_Id : Entity_Id;
16332 Prev_Par : Node_Id;
16334 procedure Check_Duplicate_Aspects;
16335 -- Check that aspects specified in a completion have not been specified
16336 -- already in the partial view. Type_Invariant and others can be
16337 -- specified on either view but never on both.
16339 procedure Tag_Mismatch;
16340 -- Diagnose a tagged partial view whose full view is untagged.
16341 -- We post the message on the full view, with a reference to
16342 -- the previous partial view. The partial view can be private
16343 -- or incomplete, and these are handled in a different manner,
16344 -- so we determine the position of the error message from the
16345 -- respective slocs of both.
16347 -----------------------------
16348 -- Check_Duplicate_Aspects --
16349 -----------------------------
16351 procedure Check_Duplicate_Aspects is
16352 Prev_Aspects : constant List_Id := Aspect_Specifications (Prev_Par);
16353 Full_Aspects : constant List_Id := Aspect_Specifications (N);
16354 F_Spec, P_Spec : Node_Id;
16357 if Present (Full_Aspects) then
16358 F_Spec := First (Full_Aspects);
16359 while Present (F_Spec) loop
16360 if Present (Prev_Aspects) then
16361 P_Spec := First (Prev_Aspects);
16362 while Present (P_Spec) loop
16363 if Chars (Identifier (P_Spec)) =
16364 Chars (Identifier (F_Spec))
16367 ("aspect already specified in private declaration",
16377 if Has_Discriminants (Prev)
16378 and then not Has_Unknown_Discriminants (Prev)
16379 and then Chars (Identifier (F_Spec)) =
16380 Name_Implicit_Dereference
16382 Error_Msg_N ("cannot specify aspect " &
16383 "if partial view has known discriminants", F_Spec);
16389 end Check_Duplicate_Aspects;
16395 procedure Tag_Mismatch is
16397 if Sloc (Prev) < Sloc (Id) then
16398 if Ada_Version >= Ada_2012
16399 and then Nkind (N) = N_Private_Type_Declaration
16402 ("declaration of private } must be a tagged type ", Id, Prev);
16405 ("full declaration of } must be a tagged type ", Id, Prev);
16409 if Ada_Version >= Ada_2012
16410 and then Nkind (N) = N_Private_Type_Declaration
16413 ("declaration of private } must be a tagged type ", Prev, Id);
16416 ("full declaration of } must be a tagged type ", Prev, Id);
16421 -- Start of processing for Find_Type_Name
16424 -- Find incomplete declaration, if one was given
16426 Prev := Current_Entity_In_Scope (Id);
16428 -- New type declaration
16434 -- Previous declaration exists
16437 Prev_Par := Parent (Prev);
16439 -- Error if not incomplete/private case except if previous
16440 -- declaration is implicit, etc. Enter_Name will emit error if
16443 if not Is_Incomplete_Or_Private_Type (Prev) then
16447 -- Check invalid completion of private or incomplete type
16449 elsif not Nkind_In (N, N_Full_Type_Declaration,
16450 N_Task_Type_Declaration,
16451 N_Protected_Type_Declaration)
16453 (Ada_Version < Ada_2012
16454 or else not Is_Incomplete_Type (Prev)
16455 or else not Nkind_In (N, N_Private_Type_Declaration,
16456 N_Private_Extension_Declaration))
16458 -- Completion must be a full type declarations (RM 7.3(4))
16460 Error_Msg_Sloc := Sloc (Prev);
16461 Error_Msg_NE ("invalid completion of }", Id, Prev);
16463 -- Set scope of Id to avoid cascaded errors. Entity is never
16464 -- examined again, except when saving globals in generics.
16466 Set_Scope (Id, Current_Scope);
16469 -- If this is a repeated incomplete declaration, no further
16470 -- checks are possible.
16472 if Nkind (N) = N_Incomplete_Type_Declaration then
16476 -- Case of full declaration of incomplete type
16478 elsif Ekind (Prev) = E_Incomplete_Type
16479 and then (Ada_Version < Ada_2012
16480 or else No (Full_View (Prev))
16481 or else not Is_Private_Type (Full_View (Prev)))
16483 -- Indicate that the incomplete declaration has a matching full
16484 -- declaration. The defining occurrence of the incomplete
16485 -- declaration remains the visible one, and the procedure
16486 -- Get_Full_View dereferences it whenever the type is used.
16488 if Present (Full_View (Prev)) then
16489 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
16492 Set_Full_View (Prev, Id);
16493 Append_Entity (Id, Current_Scope);
16494 Set_Is_Public (Id, Is_Public (Prev));
16495 Set_Is_Internal (Id);
16498 -- If the incomplete view is tagged, a class_wide type has been
16499 -- created already. Use it for the private type as well, in order
16500 -- to prevent multiple incompatible class-wide types that may be
16501 -- created for self-referential anonymous access components.
16503 if Is_Tagged_Type (Prev)
16504 and then Present (Class_Wide_Type (Prev))
16506 Set_Ekind (Id, Ekind (Prev)); -- will be reset later
16507 Set_Class_Wide_Type (Id, Class_Wide_Type (Prev));
16509 -- The type of the classwide type is the current Id. Previously
16510 -- this was not done for private declarations because of order-
16511 -- of elaboration issues in the back-end, but gigi now handles
16514 Set_Etype (Class_Wide_Type (Id), Id);
16517 -- Case of full declaration of private type
16520 -- If the private type was a completion of an incomplete type then
16521 -- update Prev to reference the private type
16523 if Ada_Version >= Ada_2012
16524 and then Ekind (Prev) = E_Incomplete_Type
16525 and then Present (Full_View (Prev))
16526 and then Is_Private_Type (Full_View (Prev))
16528 Prev := Full_View (Prev);
16529 Prev_Par := Parent (Prev);
16532 if Nkind (N) = N_Full_Type_Declaration
16534 (Type_Definition (N), N_Record_Definition,
16535 N_Derived_Type_Definition)
16536 and then Interface_Present (Type_Definition (N))
16539 ("completion of private type cannot be an interface", N);
16542 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
16543 if Etype (Prev) /= Prev then
16545 -- Prev is a private subtype or a derived type, and needs
16548 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
16551 elsif Ekind (Prev) = E_Private_Type
16552 and then Nkind_In (N, N_Task_Type_Declaration,
16553 N_Protected_Type_Declaration)
16556 ("completion of nonlimited type cannot be limited", N);
16558 elsif Ekind (Prev) = E_Record_Type_With_Private
16559 and then Nkind_In (N, N_Task_Type_Declaration,
16560 N_Protected_Type_Declaration)
16562 if not Is_Limited_Record (Prev) then
16564 ("completion of nonlimited type cannot be limited", N);
16566 elsif No (Interface_List (N)) then
16568 ("completion of tagged private type must be tagged",
16573 -- Ada 2005 (AI-251): Private extension declaration of a task
16574 -- type or a protected type. This case arises when covering
16575 -- interface types.
16577 elsif Nkind_In (N, N_Task_Type_Declaration,
16578 N_Protected_Type_Declaration)
16582 elsif Nkind (N) /= N_Full_Type_Declaration
16583 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
16586 ("full view of private extension must be an extension", N);
16588 elsif not (Abstract_Present (Parent (Prev)))
16589 and then Abstract_Present (Type_Definition (N))
16592 ("full view of non-abstract extension cannot be abstract", N);
16595 if not In_Private_Part (Current_Scope) then
16597 ("declaration of full view must appear in private part", N);
16600 if Ada_Version >= Ada_2012 then
16601 Check_Duplicate_Aspects;
16604 Copy_And_Swap (Prev, Id);
16605 Set_Has_Private_Declaration (Prev);
16606 Set_Has_Private_Declaration (Id);
16608 -- AI12-0133: Indicate whether we have a partial view with
16609 -- unknown discriminants, in which case initialization of objects
16610 -- of the type do not receive an invariant check.
16612 Set_Partial_View_Has_Unknown_Discr
16613 (Prev, Has_Unknown_Discriminants (Id));
16615 -- Preserve aspect and iterator flags that may have been set on
16616 -- the partial view.
16618 Set_Has_Delayed_Aspects (Prev, Has_Delayed_Aspects (Id));
16619 Set_Has_Implicit_Dereference (Prev, Has_Implicit_Dereference (Id));
16621 -- If no error, propagate freeze_node from private to full view.
16622 -- It may have been generated for an early operational item.
16624 if Present (Freeze_Node (Id))
16625 and then Serious_Errors_Detected = 0
16626 and then No (Full_View (Id))
16628 Set_Freeze_Node (Prev, Freeze_Node (Id));
16629 Set_Freeze_Node (Id, Empty);
16630 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
16633 Set_Full_View (Id, Prev);
16637 -- Verify that full declaration conforms to partial one
16639 if Is_Incomplete_Or_Private_Type (Prev)
16640 and then Present (Discriminant_Specifications (Prev_Par))
16642 if Present (Discriminant_Specifications (N)) then
16643 if Ekind (Prev) = E_Incomplete_Type then
16644 Check_Discriminant_Conformance (N, Prev, Prev);
16646 Check_Discriminant_Conformance (N, Prev, Id);
16651 ("missing discriminants in full type declaration", N);
16653 -- To avoid cascaded errors on subsequent use, share the
16654 -- discriminants of the partial view.
16656 Set_Discriminant_Specifications (N,
16657 Discriminant_Specifications (Prev_Par));
16661 -- A prior untagged partial view can have an associated class-wide
16662 -- type due to use of the class attribute, and in this case the full
16663 -- type must also be tagged. This Ada 95 usage is deprecated in favor
16664 -- of incomplete tagged declarations, but we check for it.
16667 and then (Is_Tagged_Type (Prev)
16668 or else Present (Class_Wide_Type (Prev)))
16670 -- Ada 2012 (AI05-0162): A private type may be the completion of
16671 -- an incomplete type.
16673 if Ada_Version >= Ada_2012
16674 and then Is_Incomplete_Type (Prev)
16675 and then Nkind_In (N, N_Private_Type_Declaration,
16676 N_Private_Extension_Declaration)
16678 -- No need to check private extensions since they are tagged
16680 if Nkind (N) = N_Private_Type_Declaration
16681 and then not Tagged_Present (N)
16686 -- The full declaration is either a tagged type (including
16687 -- a synchronized type that implements interfaces) or a
16688 -- type extension, otherwise this is an error.
16690 elsif Nkind_In (N, N_Task_Type_Declaration,
16691 N_Protected_Type_Declaration)
16693 if No (Interface_List (N)) and then not Error_Posted (N) then
16697 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
16699 -- Indicate that the previous declaration (tagged incomplete
16700 -- or private declaration) requires the same on the full one.
16702 if not Tagged_Present (Type_Definition (N)) then
16704 Set_Is_Tagged_Type (Id);
16707 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
16708 if No (Record_Extension_Part (Type_Definition (N))) then
16710 ("full declaration of } must be a record extension",
16713 -- Set some attributes to produce a usable full view
16715 Set_Is_Tagged_Type (Id);
16724 and then Nkind (Parent (Prev)) = N_Incomplete_Type_Declaration
16725 and then Present (Premature_Use (Parent (Prev)))
16727 Error_Msg_Sloc := Sloc (N);
16729 ("\full declaration #", Premature_Use (Parent (Prev)));
16734 end Find_Type_Name;
16736 -------------------------
16737 -- Find_Type_Of_Object --
16738 -------------------------
16740 function Find_Type_Of_Object
16741 (Obj_Def : Node_Id;
16742 Related_Nod : Node_Id) return Entity_Id
16744 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
16745 P : Node_Id := Parent (Obj_Def);
16750 -- If the parent is a component_definition node we climb to the
16751 -- component_declaration node
16753 if Nkind (P) = N_Component_Definition then
16757 -- Case of an anonymous array subtype
16759 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
16760 N_Unconstrained_Array_Definition)
16763 Array_Type_Declaration (T, Obj_Def);
16765 -- Create an explicit subtype whenever possible
16767 elsif Nkind (P) /= N_Component_Declaration
16768 and then Def_Kind = N_Subtype_Indication
16770 -- Base name of subtype on object name, which will be unique in
16771 -- the current scope.
16773 -- If this is a duplicate declaration, return base type, to avoid
16774 -- generating duplicate anonymous types.
16776 if Error_Posted (P) then
16777 Analyze (Subtype_Mark (Obj_Def));
16778 return Entity (Subtype_Mark (Obj_Def));
16783 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
16785 T := Make_Defining_Identifier (Sloc (P), Nam);
16787 Insert_Action (Obj_Def,
16788 Make_Subtype_Declaration (Sloc (P),
16789 Defining_Identifier => T,
16790 Subtype_Indication => Relocate_Node (Obj_Def)));
16792 -- This subtype may need freezing, and this will not be done
16793 -- automatically if the object declaration is not in declarative
16794 -- part. Since this is an object declaration, the type cannot always
16795 -- be frozen here. Deferred constants do not freeze their type
16796 -- (which often enough will be private).
16798 if Nkind (P) = N_Object_Declaration
16799 and then Constant_Present (P)
16800 and then No (Expression (P))
16804 -- Here we freeze the base type of object type to catch premature use
16805 -- of discriminated private type without a full view.
16808 Insert_Actions (Obj_Def, Freeze_Entity (Base_Type (T), P));
16811 -- Ada 2005 AI-406: the object definition in an object declaration
16812 -- can be an access definition.
16814 elsif Def_Kind = N_Access_Definition then
16815 T := Access_Definition (Related_Nod, Obj_Def);
16817 Set_Is_Local_Anonymous_Access
16819 V => (Ada_Version < Ada_2012)
16820 or else (Nkind (P) /= N_Object_Declaration)
16821 or else Is_Library_Level_Entity (Defining_Identifier (P)));
16823 -- Otherwise, the object definition is just a subtype_mark
16826 T := Process_Subtype (Obj_Def, Related_Nod);
16828 -- If expansion is disabled an object definition that is an aggregate
16829 -- will not get expanded and may lead to scoping problems in the back
16830 -- end, if the object is referenced in an inner scope. In that case
16831 -- create an itype reference for the object definition now. This
16832 -- may be redundant in some cases, but harmless.
16835 and then Nkind (Related_Nod) = N_Object_Declaration
16838 Build_Itype_Reference (T, Related_Nod);
16843 end Find_Type_Of_Object;
16845 --------------------------------
16846 -- Find_Type_Of_Subtype_Indic --
16847 --------------------------------
16849 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
16853 -- Case of subtype mark with a constraint
16855 if Nkind (S) = N_Subtype_Indication then
16856 Find_Type (Subtype_Mark (S));
16857 Typ := Entity (Subtype_Mark (S));
16860 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
16863 ("incorrect constraint for this kind of type", Constraint (S));
16864 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
16867 -- Otherwise we have a subtype mark without a constraint
16869 elsif Error_Posted (S) then
16870 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
16878 -- Check No_Wide_Characters restriction
16880 Check_Wide_Character_Restriction (Typ, S);
16883 end Find_Type_Of_Subtype_Indic;
16885 -------------------------------------
16886 -- Floating_Point_Type_Declaration --
16887 -------------------------------------
16889 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
16890 Digs : constant Node_Id := Digits_Expression (Def);
16891 Max_Digs_Val : constant Uint := Digits_Value (Standard_Long_Long_Float);
16893 Base_Typ : Entity_Id;
16894 Implicit_Base : Entity_Id;
16897 function Can_Derive_From (E : Entity_Id) return Boolean;
16898 -- Find if given digits value, and possibly a specified range, allows
16899 -- derivation from specified type
16901 function Find_Base_Type return Entity_Id;
16902 -- Find a predefined base type that Def can derive from, or generate
16903 -- an error and substitute Long_Long_Float if none exists.
16905 ---------------------
16906 -- Can_Derive_From --
16907 ---------------------
16909 function Can_Derive_From (E : Entity_Id) return Boolean is
16910 Spec : constant Entity_Id := Real_Range_Specification (Def);
16913 -- Check specified "digits" constraint
16915 if Digs_Val > Digits_Value (E) then
16919 -- Check for matching range, if specified
16921 if Present (Spec) then
16922 if Expr_Value_R (Type_Low_Bound (E)) >
16923 Expr_Value_R (Low_Bound (Spec))
16928 if Expr_Value_R (Type_High_Bound (E)) <
16929 Expr_Value_R (High_Bound (Spec))
16936 end Can_Derive_From;
16938 --------------------
16939 -- Find_Base_Type --
16940 --------------------
16942 function Find_Base_Type return Entity_Id is
16943 Choice : Elmt_Id := First_Elmt (Predefined_Float_Types);
16946 -- Iterate over the predefined types in order, returning the first
16947 -- one that Def can derive from.
16949 while Present (Choice) loop
16950 if Can_Derive_From (Node (Choice)) then
16951 return Node (Choice);
16954 Next_Elmt (Choice);
16957 -- If we can't derive from any existing type, use Long_Long_Float
16958 -- and give appropriate message explaining the problem.
16960 if Digs_Val > Max_Digs_Val then
16961 -- It might be the case that there is a type with the requested
16962 -- range, just not the combination of digits and range.
16965 ("no predefined type has requested range and precision",
16966 Real_Range_Specification (Def));
16970 ("range too large for any predefined type",
16971 Real_Range_Specification (Def));
16974 return Standard_Long_Long_Float;
16975 end Find_Base_Type;
16977 -- Start of processing for Floating_Point_Type_Declaration
16980 Check_Restriction (No_Floating_Point, Def);
16982 -- Create an implicit base type
16985 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
16987 -- Analyze and verify digits value
16989 Analyze_And_Resolve (Digs, Any_Integer);
16990 Check_Digits_Expression (Digs);
16991 Digs_Val := Expr_Value (Digs);
16993 -- Process possible range spec and find correct type to derive from
16995 Process_Real_Range_Specification (Def);
16997 -- Check that requested number of digits is not too high.
16999 if Digs_Val > Max_Digs_Val then
17001 -- The check for Max_Base_Digits may be somewhat expensive, as it
17002 -- requires reading System, so only do it when necessary.
17005 Max_Base_Digits : constant Uint :=
17008 (Parent (RTE (RE_Max_Base_Digits))));
17011 if Digs_Val > Max_Base_Digits then
17012 Error_Msg_Uint_1 := Max_Base_Digits;
17013 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
17015 elsif No (Real_Range_Specification (Def)) then
17016 Error_Msg_Uint_1 := Max_Digs_Val;
17017 Error_Msg_N ("types with more than ^ digits need range spec "
17018 & "(RM 3.5.7(6))", Digs);
17023 -- Find a suitable type to derive from or complain and use a substitute
17025 Base_Typ := Find_Base_Type;
17027 -- If there are bounds given in the declaration use them as the bounds
17028 -- of the type, otherwise use the bounds of the predefined base type
17029 -- that was chosen based on the Digits value.
17031 if Present (Real_Range_Specification (Def)) then
17032 Set_Scalar_Range (T, Real_Range_Specification (Def));
17033 Set_Is_Constrained (T);
17035 -- The bounds of this range must be converted to machine numbers
17036 -- in accordance with RM 4.9(38).
17038 Bound := Type_Low_Bound (T);
17040 if Nkind (Bound) = N_Real_Literal then
17042 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
17043 Set_Is_Machine_Number (Bound);
17046 Bound := Type_High_Bound (T);
17048 if Nkind (Bound) = N_Real_Literal then
17050 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
17051 Set_Is_Machine_Number (Bound);
17055 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
17058 -- Complete definition of implicit base and declared first subtype. The
17059 -- inheritance of the rep item chain ensures that SPARK-related pragmas
17060 -- are not clobbered when the floating point type acts as a full view of
17063 Set_Etype (Implicit_Base, Base_Typ);
17064 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
17065 Set_Size_Info (Implicit_Base, Base_Typ);
17066 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
17067 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
17068 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
17069 Set_Float_Rep (Implicit_Base, Float_Rep (Base_Typ));
17071 Set_Ekind (T, E_Floating_Point_Subtype);
17072 Set_Etype (T, Implicit_Base);
17073 Set_Size_Info (T, Implicit_Base);
17074 Set_RM_Size (T, RM_Size (Implicit_Base));
17075 Inherit_Rep_Item_Chain (T, Implicit_Base);
17076 Set_Digits_Value (T, Digs_Val);
17077 end Floating_Point_Type_Declaration;
17079 ----------------------------
17080 -- Get_Discriminant_Value --
17081 ----------------------------
17083 -- This is the situation:
17085 -- There is a non-derived type
17087 -- type T0 (Dx, Dy, Dz...)
17089 -- There are zero or more levels of derivation, with each derivation
17090 -- either purely inheriting the discriminants, or defining its own.
17092 -- type Ti is new Ti-1
17094 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
17096 -- subtype Ti is ...
17098 -- The subtype issue is avoided by the use of Original_Record_Component,
17099 -- and the fact that derived subtypes also derive the constraints.
17101 -- This chain leads back from
17103 -- Typ_For_Constraint
17105 -- Typ_For_Constraint has discriminants, and the value for each
17106 -- discriminant is given by its corresponding Elmt of Constraints.
17108 -- Discriminant is some discriminant in this hierarchy
17110 -- We need to return its value
17112 -- We do this by recursively searching each level, and looking for
17113 -- Discriminant. Once we get to the bottom, we start backing up
17114 -- returning the value for it which may in turn be a discriminant
17115 -- further up, so on the backup we continue the substitution.
17117 function Get_Discriminant_Value
17118 (Discriminant : Entity_Id;
17119 Typ_For_Constraint : Entity_Id;
17120 Constraint : Elist_Id) return Node_Id
17122 function Root_Corresponding_Discriminant
17123 (Discr : Entity_Id) return Entity_Id;
17124 -- Given a discriminant, traverse the chain of inherited discriminants
17125 -- and return the topmost discriminant.
17127 function Search_Derivation_Levels
17129 Discrim_Values : Elist_Id;
17130 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
17131 -- This is the routine that performs the recursive search of levels
17132 -- as described above.
17134 -------------------------------------
17135 -- Root_Corresponding_Discriminant --
17136 -------------------------------------
17138 function Root_Corresponding_Discriminant
17139 (Discr : Entity_Id) return Entity_Id
17145 while Present (Corresponding_Discriminant (D)) loop
17146 D := Corresponding_Discriminant (D);
17150 end Root_Corresponding_Discriminant;
17152 ------------------------------
17153 -- Search_Derivation_Levels --
17154 ------------------------------
17156 function Search_Derivation_Levels
17158 Discrim_Values : Elist_Id;
17159 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
17163 Result : Node_Or_Entity_Id;
17164 Result_Entity : Node_Id;
17167 -- If inappropriate type, return Error, this happens only in
17168 -- cascaded error situations, and we want to avoid a blow up.
17170 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
17174 -- Look deeper if possible. Use Stored_Constraints only for
17175 -- untagged types. For tagged types use the given constraint.
17176 -- This asymmetry needs explanation???
17178 if not Stored_Discrim_Values
17179 and then Present (Stored_Constraint (Ti))
17180 and then not Is_Tagged_Type (Ti)
17183 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
17186 Td : constant Entity_Id := Etype (Ti);
17190 Result := Discriminant;
17193 if Present (Stored_Constraint (Ti)) then
17195 Search_Derivation_Levels
17196 (Td, Stored_Constraint (Ti), True);
17199 Search_Derivation_Levels
17200 (Td, Discrim_Values, Stored_Discrim_Values);
17206 -- Extra underlying places to search, if not found above. For
17207 -- concurrent types, the relevant discriminant appears in the
17208 -- corresponding record. For a type derived from a private type
17209 -- without discriminant, the full view inherits the discriminants
17210 -- of the full view of the parent.
17212 if Result = Discriminant then
17213 if Is_Concurrent_Type (Ti)
17214 and then Present (Corresponding_Record_Type (Ti))
17217 Search_Derivation_Levels (
17218 Corresponding_Record_Type (Ti),
17220 Stored_Discrim_Values);
17222 elsif Is_Private_Type (Ti)
17223 and then not Has_Discriminants (Ti)
17224 and then Present (Full_View (Ti))
17225 and then Etype (Full_View (Ti)) /= Ti
17228 Search_Derivation_Levels (
17231 Stored_Discrim_Values);
17235 -- If Result is not a (reference to a) discriminant, return it,
17236 -- otherwise set Result_Entity to the discriminant.
17238 if Nkind (Result) = N_Defining_Identifier then
17239 pragma Assert (Result = Discriminant);
17240 Result_Entity := Result;
17243 if not Denotes_Discriminant (Result) then
17247 Result_Entity := Entity (Result);
17250 -- See if this level of derivation actually has discriminants because
17251 -- tagged derivations can add them, hence the lower levels need not
17254 if not Has_Discriminants (Ti) then
17258 -- Scan Ti's discriminants for Result_Entity, and return its
17259 -- corresponding value, if any.
17261 Result_Entity := Original_Record_Component (Result_Entity);
17263 Assoc := First_Elmt (Discrim_Values);
17265 if Stored_Discrim_Values then
17266 Disc := First_Stored_Discriminant (Ti);
17268 Disc := First_Discriminant (Ti);
17271 while Present (Disc) loop
17272 pragma Assert (Present (Assoc));
17274 if Original_Record_Component (Disc) = Result_Entity then
17275 return Node (Assoc);
17280 if Stored_Discrim_Values then
17281 Next_Stored_Discriminant (Disc);
17283 Next_Discriminant (Disc);
17287 -- Could not find it
17290 end Search_Derivation_Levels;
17294 Result : Node_Or_Entity_Id;
17296 -- Start of processing for Get_Discriminant_Value
17299 -- ??? This routine is a gigantic mess and will be deleted. For the
17300 -- time being just test for the trivial case before calling recurse.
17302 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
17308 D := First_Discriminant (Typ_For_Constraint);
17309 E := First_Elmt (Constraint);
17310 while Present (D) loop
17311 if Chars (D) = Chars (Discriminant) then
17315 Next_Discriminant (D);
17321 Result := Search_Derivation_Levels
17322 (Typ_For_Constraint, Constraint, False);
17324 -- ??? hack to disappear when this routine is gone
17326 if Nkind (Result) = N_Defining_Identifier then
17332 D := First_Discriminant (Typ_For_Constraint);
17333 E := First_Elmt (Constraint);
17334 while Present (D) loop
17335 if Root_Corresponding_Discriminant (D) = Discriminant then
17339 Next_Discriminant (D);
17345 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
17347 end Get_Discriminant_Value;
17349 --------------------------
17350 -- Has_Range_Constraint --
17351 --------------------------
17353 function Has_Range_Constraint (N : Node_Id) return Boolean is
17354 C : constant Node_Id := Constraint (N);
17357 if Nkind (C) = N_Range_Constraint then
17360 elsif Nkind (C) = N_Digits_Constraint then
17362 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
17363 or else Present (Range_Constraint (C));
17365 elsif Nkind (C) = N_Delta_Constraint then
17366 return Present (Range_Constraint (C));
17371 end Has_Range_Constraint;
17373 ------------------------
17374 -- Inherit_Components --
17375 ------------------------
17377 function Inherit_Components
17379 Parent_Base : Entity_Id;
17380 Derived_Base : Entity_Id;
17381 Is_Tagged : Boolean;
17382 Inherit_Discr : Boolean;
17383 Discs : Elist_Id) return Elist_Id
17385 Assoc_List : constant Elist_Id := New_Elmt_List;
17387 procedure Inherit_Component
17388 (Old_C : Entity_Id;
17389 Plain_Discrim : Boolean := False;
17390 Stored_Discrim : Boolean := False);
17391 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
17392 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
17393 -- True, Old_C is a stored discriminant. If they are both false then
17394 -- Old_C is a regular component.
17396 -----------------------
17397 -- Inherit_Component --
17398 -----------------------
17400 procedure Inherit_Component
17401 (Old_C : Entity_Id;
17402 Plain_Discrim : Boolean := False;
17403 Stored_Discrim : Boolean := False)
17405 procedure Set_Anonymous_Type (Id : Entity_Id);
17406 -- Id denotes the entity of an access discriminant or anonymous
17407 -- access component. Set the type of Id to either the same type of
17408 -- Old_C or create a new one depending on whether the parent and
17409 -- the child types are in the same scope.
17411 ------------------------
17412 -- Set_Anonymous_Type --
17413 ------------------------
17415 procedure Set_Anonymous_Type (Id : Entity_Id) is
17416 Old_Typ : constant Entity_Id := Etype (Old_C);
17419 if Scope (Parent_Base) = Scope (Derived_Base) then
17420 Set_Etype (Id, Old_Typ);
17422 -- The parent and the derived type are in two different scopes.
17423 -- Reuse the type of the original discriminant / component by
17424 -- copying it in order to preserve all attributes.
17428 Typ : constant Entity_Id := New_Copy (Old_Typ);
17431 Set_Etype (Id, Typ);
17433 -- Since we do not generate component declarations for
17434 -- inherited components, associate the itype with the
17437 Set_Associated_Node_For_Itype (Typ, Parent (Derived_Base));
17438 Set_Scope (Typ, Derived_Base);
17441 end Set_Anonymous_Type;
17443 -- Local variables and constants
17445 New_C : constant Entity_Id := New_Copy (Old_C);
17447 Corr_Discrim : Entity_Id;
17448 Discrim : Entity_Id;
17450 -- Start of processing for Inherit_Component
17453 pragma Assert (not Is_Tagged or not Stored_Discrim);
17455 Set_Parent (New_C, Parent (Old_C));
17457 -- Regular discriminants and components must be inserted in the scope
17458 -- of the Derived_Base. Do it here.
17460 if not Stored_Discrim then
17461 Enter_Name (New_C);
17464 -- For tagged types the Original_Record_Component must point to
17465 -- whatever this field was pointing to in the parent type. This has
17466 -- already been achieved by the call to New_Copy above.
17468 if not Is_Tagged then
17469 Set_Original_Record_Component (New_C, New_C);
17472 -- Set the proper type of an access discriminant
17474 if Ekind (New_C) = E_Discriminant
17475 and then Ekind (Etype (New_C)) = E_Anonymous_Access_Type
17477 Set_Anonymous_Type (New_C);
17480 -- If we have inherited a component then see if its Etype contains
17481 -- references to Parent_Base discriminants. In this case, replace
17482 -- these references with the constraints given in Discs. We do not
17483 -- do this for the partial view of private types because this is
17484 -- not needed (only the components of the full view will be used
17485 -- for code generation) and cause problem. We also avoid this
17486 -- transformation in some error situations.
17488 if Ekind (New_C) = E_Component then
17490 -- Set the proper type of an anonymous access component
17492 if Ekind (Etype (New_C)) = E_Anonymous_Access_Type then
17493 Set_Anonymous_Type (New_C);
17495 elsif (Is_Private_Type (Derived_Base)
17496 and then not Is_Generic_Type (Derived_Base))
17497 or else (Is_Empty_Elmt_List (Discs)
17498 and then not Expander_Active)
17500 Set_Etype (New_C, Etype (Old_C));
17503 -- The current component introduces a circularity of the
17506 -- limited with Pack_2;
17507 -- package Pack_1 is
17508 -- type T_1 is tagged record
17509 -- Comp : access Pack_2.T_2;
17515 -- package Pack_2 is
17516 -- type T_2 is new Pack_1.T_1 with ...;
17521 Constrain_Component_Type
17522 (Old_C, Derived_Base, N, Parent_Base, Discs));
17526 -- In derived tagged types it is illegal to reference a non
17527 -- discriminant component in the parent type. To catch this, mark
17528 -- these components with an Ekind of E_Void. This will be reset in
17529 -- Record_Type_Definition after processing the record extension of
17530 -- the derived type.
17532 -- If the declaration is a private extension, there is no further
17533 -- record extension to process, and the components retain their
17534 -- current kind, because they are visible at this point.
17536 if Is_Tagged and then Ekind (New_C) = E_Component
17537 and then Nkind (N) /= N_Private_Extension_Declaration
17539 Set_Ekind (New_C, E_Void);
17542 if Plain_Discrim then
17543 Set_Corresponding_Discriminant (New_C, Old_C);
17544 Build_Discriminal (New_C);
17546 -- If we are explicitly inheriting a stored discriminant it will be
17547 -- completely hidden.
17549 elsif Stored_Discrim then
17550 Set_Corresponding_Discriminant (New_C, Empty);
17551 Set_Discriminal (New_C, Empty);
17552 Set_Is_Completely_Hidden (New_C);
17554 -- Set the Original_Record_Component of each discriminant in the
17555 -- derived base to point to the corresponding stored that we just
17558 Discrim := First_Discriminant (Derived_Base);
17559 while Present (Discrim) loop
17560 Corr_Discrim := Corresponding_Discriminant (Discrim);
17562 -- Corr_Discrim could be missing in an error situation
17564 if Present (Corr_Discrim)
17565 and then Original_Record_Component (Corr_Discrim) = Old_C
17567 Set_Original_Record_Component (Discrim, New_C);
17570 Next_Discriminant (Discrim);
17573 Append_Entity (New_C, Derived_Base);
17576 if not Is_Tagged then
17577 Append_Elmt (Old_C, Assoc_List);
17578 Append_Elmt (New_C, Assoc_List);
17580 end Inherit_Component;
17582 -- Variables local to Inherit_Component
17584 Loc : constant Source_Ptr := Sloc (N);
17586 Parent_Discrim : Entity_Id;
17587 Stored_Discrim : Entity_Id;
17589 Component : Entity_Id;
17591 -- Start of processing for Inherit_Components
17594 if not Is_Tagged then
17595 Append_Elmt (Parent_Base, Assoc_List);
17596 Append_Elmt (Derived_Base, Assoc_List);
17599 -- Inherit parent discriminants if needed
17601 if Inherit_Discr then
17602 Parent_Discrim := First_Discriminant (Parent_Base);
17603 while Present (Parent_Discrim) loop
17604 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
17605 Next_Discriminant (Parent_Discrim);
17609 -- Create explicit stored discrims for untagged types when necessary
17611 if not Has_Unknown_Discriminants (Derived_Base)
17612 and then Has_Discriminants (Parent_Base)
17613 and then not Is_Tagged
17616 or else First_Discriminant (Parent_Base) /=
17617 First_Stored_Discriminant (Parent_Base))
17619 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
17620 while Present (Stored_Discrim) loop
17621 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
17622 Next_Stored_Discriminant (Stored_Discrim);
17626 -- See if we can apply the second transformation for derived types, as
17627 -- explained in point 6. in the comments above Build_Derived_Record_Type
17628 -- This is achieved by appending Derived_Base discriminants into Discs,
17629 -- which has the side effect of returning a non empty Discs list to the
17630 -- caller of Inherit_Components, which is what we want. This must be
17631 -- done for private derived types if there are explicit stored
17632 -- discriminants, to ensure that we can retrieve the values of the
17633 -- constraints provided in the ancestors.
17636 and then Is_Empty_Elmt_List (Discs)
17637 and then Present (First_Discriminant (Derived_Base))
17639 (not Is_Private_Type (Derived_Base)
17640 or else Is_Completely_Hidden
17641 (First_Stored_Discriminant (Derived_Base))
17642 or else Is_Generic_Type (Derived_Base))
17644 D := First_Discriminant (Derived_Base);
17645 while Present (D) loop
17646 Append_Elmt (New_Occurrence_Of (D, Loc), Discs);
17647 Next_Discriminant (D);
17651 -- Finally, inherit non-discriminant components unless they are not
17652 -- visible because defined or inherited from the full view of the
17653 -- parent. Don't inherit the _parent field of the parent type.
17655 Component := First_Entity (Parent_Base);
17656 while Present (Component) loop
17658 -- Ada 2005 (AI-251): Do not inherit components associated with
17659 -- secondary tags of the parent.
17661 if Ekind (Component) = E_Component
17662 and then Present (Related_Type (Component))
17666 elsif Ekind (Component) /= E_Component
17667 or else Chars (Component) = Name_uParent
17671 -- If the derived type is within the parent type's declarative
17672 -- region, then the components can still be inherited even though
17673 -- they aren't visible at this point. This can occur for cases
17674 -- such as within public child units where the components must
17675 -- become visible upon entering the child unit's private part.
17677 elsif not Is_Visible_Component (Component)
17678 and then not In_Open_Scopes (Scope (Parent_Base))
17682 elsif Ekind_In (Derived_Base, E_Private_Type,
17683 E_Limited_Private_Type)
17688 Inherit_Component (Component);
17691 Next_Entity (Component);
17694 -- For tagged derived types, inherited discriminants cannot be used in
17695 -- component declarations of the record extension part. To achieve this
17696 -- we mark the inherited discriminants as not visible.
17698 if Is_Tagged and then Inherit_Discr then
17699 D := First_Discriminant (Derived_Base);
17700 while Present (D) loop
17701 Set_Is_Immediately_Visible (D, False);
17702 Next_Discriminant (D);
17707 end Inherit_Components;
17709 -----------------------------
17710 -- Inherit_Predicate_Flags --
17711 -----------------------------
17713 procedure Inherit_Predicate_Flags (Subt, Par : Entity_Id) is
17715 Set_Has_Predicates (Subt, Has_Predicates (Par));
17716 Set_Has_Static_Predicate_Aspect
17717 (Subt, Has_Static_Predicate_Aspect (Par));
17718 Set_Has_Dynamic_Predicate_Aspect
17719 (Subt, Has_Dynamic_Predicate_Aspect (Par));
17720 end Inherit_Predicate_Flags;
17722 ----------------------
17723 -- Is_EVF_Procedure --
17724 ----------------------
17726 function Is_EVF_Procedure (Subp : Entity_Id) return Boolean is
17727 Formal : Entity_Id;
17730 -- Examine the formals of an Extensions_Visible False procedure looking
17731 -- for a controlling OUT parameter.
17733 if Ekind (Subp) = E_Procedure
17734 and then Extensions_Visible_Status (Subp) = Extensions_Visible_False
17736 Formal := First_Formal (Subp);
17737 while Present (Formal) loop
17738 if Ekind (Formal) = E_Out_Parameter
17739 and then Is_Controlling_Formal (Formal)
17744 Next_Formal (Formal);
17749 end Is_EVF_Procedure;
17751 -----------------------
17752 -- Is_Null_Extension --
17753 -----------------------
17755 function Is_Null_Extension (T : Entity_Id) return Boolean is
17756 Type_Decl : constant Node_Id := Parent (Base_Type (T));
17757 Comp_List : Node_Id;
17761 if Nkind (Type_Decl) /= N_Full_Type_Declaration
17762 or else not Is_Tagged_Type (T)
17763 or else Nkind (Type_Definition (Type_Decl)) /=
17764 N_Derived_Type_Definition
17765 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
17771 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
17773 if Present (Discriminant_Specifications (Type_Decl)) then
17776 elsif Present (Comp_List)
17777 and then Is_Non_Empty_List (Component_Items (Comp_List))
17779 Comp := First (Component_Items (Comp_List));
17781 -- Only user-defined components are relevant. The component list
17782 -- may also contain a parent component and internal components
17783 -- corresponding to secondary tags, but these do not determine
17784 -- whether this is a null extension.
17786 while Present (Comp) loop
17787 if Comes_From_Source (Comp) then
17799 end Is_Null_Extension;
17801 ------------------------------
17802 -- Is_Valid_Constraint_Kind --
17803 ------------------------------
17805 function Is_Valid_Constraint_Kind
17806 (T_Kind : Type_Kind;
17807 Constraint_Kind : Node_Kind) return Boolean
17811 when Enumeration_Kind |
17813 return Constraint_Kind = N_Range_Constraint;
17815 when Decimal_Fixed_Point_Kind =>
17816 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
17817 N_Range_Constraint);
17819 when Ordinary_Fixed_Point_Kind =>
17820 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
17821 N_Range_Constraint);
17824 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
17825 N_Range_Constraint);
17832 E_Incomplete_Type |
17835 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
17838 return True; -- Error will be detected later
17840 end Is_Valid_Constraint_Kind;
17842 --------------------------
17843 -- Is_Visible_Component --
17844 --------------------------
17846 function Is_Visible_Component
17848 N : Node_Id := Empty) return Boolean
17850 Original_Comp : Entity_Id := Empty;
17851 Original_Type : Entity_Id;
17852 Type_Scope : Entity_Id;
17854 function Is_Local_Type (Typ : Entity_Id) return Boolean;
17855 -- Check whether parent type of inherited component is declared locally,
17856 -- possibly within a nested package or instance. The current scope is
17857 -- the derived record itself.
17859 -------------------
17860 -- Is_Local_Type --
17861 -------------------
17863 function Is_Local_Type (Typ : Entity_Id) return Boolean is
17867 Scop := Scope (Typ);
17868 while Present (Scop)
17869 and then Scop /= Standard_Standard
17871 if Scop = Scope (Current_Scope) then
17875 Scop := Scope (Scop);
17881 -- Start of processing for Is_Visible_Component
17884 if Ekind_In (C, E_Component, E_Discriminant) then
17885 Original_Comp := Original_Record_Component (C);
17888 if No (Original_Comp) then
17890 -- Premature usage, or previous error
17895 Original_Type := Scope (Original_Comp);
17896 Type_Scope := Scope (Base_Type (Scope (C)));
17899 -- This test only concerns tagged types
17901 if not Is_Tagged_Type (Original_Type) then
17904 -- If it is _Parent or _Tag, there is no visibility issue
17906 elsif not Comes_From_Source (Original_Comp) then
17909 -- Discriminants are visible unless the (private) type has unknown
17910 -- discriminants. If the discriminant reference is inserted for a
17911 -- discriminant check on a full view it is also visible.
17913 elsif Ekind (Original_Comp) = E_Discriminant
17915 (not Has_Unknown_Discriminants (Original_Type)
17916 or else (Present (N)
17917 and then Nkind (N) = N_Selected_Component
17918 and then Nkind (Prefix (N)) = N_Type_Conversion
17919 and then not Comes_From_Source (Prefix (N))))
17923 -- In the body of an instantiation, no need to check for the visibility
17926 elsif In_Instance_Body then
17929 -- If the component has been declared in an ancestor which is currently
17930 -- a private type, then it is not visible. The same applies if the
17931 -- component's containing type is not in an open scope and the original
17932 -- component's enclosing type is a visible full view of a private type
17933 -- (which can occur in cases where an attempt is being made to reference
17934 -- a component in a sibling package that is inherited from a visible
17935 -- component of a type in an ancestor package; the component in the
17936 -- sibling package should not be visible even though the component it
17937 -- inherited from is visible). This does not apply however in the case
17938 -- where the scope of the type is a private child unit, or when the
17939 -- parent comes from a local package in which the ancestor is currently
17940 -- visible. The latter suppression of visibility is needed for cases
17941 -- that are tested in B730006.
17943 elsif Is_Private_Type (Original_Type)
17945 (not Is_Private_Descendant (Type_Scope)
17946 and then not In_Open_Scopes (Type_Scope)
17947 and then Has_Private_Declaration (Original_Type))
17949 -- If the type derives from an entity in a formal package, there
17950 -- are no additional visible components.
17952 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
17953 N_Formal_Package_Declaration
17957 -- if we are not in the private part of the current package, there
17958 -- are no additional visible components.
17960 elsif Ekind (Scope (Current_Scope)) = E_Package
17961 and then not In_Private_Part (Scope (Current_Scope))
17966 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
17967 and then In_Open_Scopes (Scope (Original_Type))
17968 and then Is_Local_Type (Type_Scope);
17971 -- There is another weird way in which a component may be invisible when
17972 -- the private and the full view are not derived from the same ancestor.
17973 -- Here is an example :
17975 -- type A1 is tagged record F1 : integer; end record;
17976 -- type A2 is new A1 with record F2 : integer; end record;
17977 -- type T is new A1 with private;
17979 -- type T is new A2 with null record;
17981 -- In this case, the full view of T inherits F1 and F2 but the private
17982 -- view inherits only F1
17986 Ancestor : Entity_Id := Scope (C);
17990 if Ancestor = Original_Type then
17993 -- The ancestor may have a partial view of the original type,
17994 -- but if the full view is in scope, as in a child body, the
17995 -- component is visible.
17997 elsif In_Private_Part (Scope (Original_Type))
17998 and then Full_View (Ancestor) = Original_Type
18002 elsif Ancestor = Etype (Ancestor) then
18004 -- No further ancestors to examine
18009 Ancestor := Etype (Ancestor);
18013 end Is_Visible_Component;
18015 --------------------------
18016 -- Make_Class_Wide_Type --
18017 --------------------------
18019 procedure Make_Class_Wide_Type (T : Entity_Id) is
18020 CW_Type : Entity_Id;
18022 Next_E : Entity_Id;
18025 if Present (Class_Wide_Type (T)) then
18027 -- The class-wide type is a partially decorated entity created for a
18028 -- unanalyzed tagged type referenced through a limited with clause.
18029 -- When the tagged type is analyzed, its class-wide type needs to be
18030 -- redecorated. Note that we reuse the entity created by Decorate_
18031 -- Tagged_Type in order to preserve all links.
18033 if Materialize_Entity (Class_Wide_Type (T)) then
18034 CW_Type := Class_Wide_Type (T);
18035 Set_Materialize_Entity (CW_Type, False);
18037 -- The class wide type can have been defined by the partial view, in
18038 -- which case everything is already done.
18044 -- Default case, we need to create a new class-wide type
18048 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
18051 -- Inherit root type characteristics
18053 CW_Name := Chars (CW_Type);
18054 Next_E := Next_Entity (CW_Type);
18055 Copy_Node (T, CW_Type);
18056 Set_Comes_From_Source (CW_Type, False);
18057 Set_Chars (CW_Type, CW_Name);
18058 Set_Parent (CW_Type, Parent (T));
18059 Set_Next_Entity (CW_Type, Next_E);
18061 -- Ensure we have a new freeze node for the class-wide type. The partial
18062 -- view may have freeze action of its own, requiring a proper freeze
18063 -- node, and the same freeze node cannot be shared between the two
18066 Set_Has_Delayed_Freeze (CW_Type);
18067 Set_Freeze_Node (CW_Type, Empty);
18069 -- Customize the class-wide type: It has no prim. op., it cannot be
18070 -- abstract and its Etype points back to the specific root type.
18072 Set_Ekind (CW_Type, E_Class_Wide_Type);
18073 Set_Is_Tagged_Type (CW_Type, True);
18074 Set_Direct_Primitive_Operations (CW_Type, New_Elmt_List);
18075 Set_Is_Abstract_Type (CW_Type, False);
18076 Set_Is_Constrained (CW_Type, False);
18077 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
18078 Set_Default_SSO (CW_Type);
18080 if Ekind (T) = E_Class_Wide_Subtype then
18081 Set_Etype (CW_Type, Etype (Base_Type (T)));
18083 Set_Etype (CW_Type, T);
18086 Set_No_Tagged_Streams_Pragma (CW_Type, No_Tagged_Streams);
18088 -- If this is the class_wide type of a constrained subtype, it does
18089 -- not have discriminants.
18091 Set_Has_Discriminants (CW_Type,
18092 Has_Discriminants (T) and then not Is_Constrained (T));
18094 Set_Has_Unknown_Discriminants (CW_Type, True);
18095 Set_Class_Wide_Type (T, CW_Type);
18096 Set_Equivalent_Type (CW_Type, Empty);
18098 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
18100 Set_Class_Wide_Type (CW_Type, CW_Type);
18102 -- Inherit the "ghostness" from the root tagged type
18104 if Ghost_Mode > None or else Is_Ghost_Entity (T) then
18105 Set_Is_Ghost_Entity (CW_Type);
18107 end Make_Class_Wide_Type;
18113 procedure Make_Index
18115 Related_Nod : Node_Id;
18116 Related_Id : Entity_Id := Empty;
18117 Suffix_Index : Nat := 1;
18118 In_Iter_Schm : Boolean := False)
18122 Def_Id : Entity_Id := Empty;
18123 Found : Boolean := False;
18126 -- For a discrete range used in a constrained array definition and
18127 -- defined by a range, an implicit conversion to the predefined type
18128 -- INTEGER is assumed if each bound is either a numeric literal, a named
18129 -- number, or an attribute, and the type of both bounds (prior to the
18130 -- implicit conversion) is the type universal_integer. Otherwise, both
18131 -- bounds must be of the same discrete type, other than universal
18132 -- integer; this type must be determinable independently of the
18133 -- context, but using the fact that the type must be discrete and that
18134 -- both bounds must have the same type.
18136 -- Character literals also have a universal type in the absence of
18137 -- of additional context, and are resolved to Standard_Character.
18139 if Nkind (N) = N_Range then
18141 -- The index is given by a range constraint. The bounds are known
18142 -- to be of a consistent type.
18144 if not Is_Overloaded (N) then
18147 -- For universal bounds, choose the specific predefined type
18149 if T = Universal_Integer then
18150 T := Standard_Integer;
18152 elsif T = Any_Character then
18153 Ambiguous_Character (Low_Bound (N));
18155 T := Standard_Character;
18158 -- The node may be overloaded because some user-defined operators
18159 -- are available, but if a universal interpretation exists it is
18160 -- also the selected one.
18162 elsif Universal_Interpretation (N) = Universal_Integer then
18163 T := Standard_Integer;
18169 Ind : Interp_Index;
18173 Get_First_Interp (N, Ind, It);
18174 while Present (It.Typ) loop
18175 if Is_Discrete_Type (It.Typ) then
18178 and then not Covers (It.Typ, T)
18179 and then not Covers (T, It.Typ)
18181 Error_Msg_N ("ambiguous bounds in discrete range", N);
18189 Get_Next_Interp (Ind, It);
18192 if T = Any_Type then
18193 Error_Msg_N ("discrete type required for range", N);
18194 Set_Etype (N, Any_Type);
18197 elsif T = Universal_Integer then
18198 T := Standard_Integer;
18203 if not Is_Discrete_Type (T) then
18204 Error_Msg_N ("discrete type required for range", N);
18205 Set_Etype (N, Any_Type);
18209 if Nkind (Low_Bound (N)) = N_Attribute_Reference
18210 and then Attribute_Name (Low_Bound (N)) = Name_First
18211 and then Is_Entity_Name (Prefix (Low_Bound (N)))
18212 and then Is_Type (Entity (Prefix (Low_Bound (N))))
18213 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (N))))
18215 -- The type of the index will be the type of the prefix, as long
18216 -- as the upper bound is 'Last of the same type.
18218 Def_Id := Entity (Prefix (Low_Bound (N)));
18220 if Nkind (High_Bound (N)) /= N_Attribute_Reference
18221 or else Attribute_Name (High_Bound (N)) /= Name_Last
18222 or else not Is_Entity_Name (Prefix (High_Bound (N)))
18223 or else Entity (Prefix (High_Bound (N))) /= Def_Id
18230 Process_Range_Expr_In_Decl (R, T, In_Iter_Schm => In_Iter_Schm);
18232 elsif Nkind (N) = N_Subtype_Indication then
18234 -- The index is given by a subtype with a range constraint
18236 T := Base_Type (Entity (Subtype_Mark (N)));
18238 if not Is_Discrete_Type (T) then
18239 Error_Msg_N ("discrete type required for range", N);
18240 Set_Etype (N, Any_Type);
18244 R := Range_Expression (Constraint (N));
18247 Process_Range_Expr_In_Decl
18248 (R, Entity (Subtype_Mark (N)), In_Iter_Schm => In_Iter_Schm);
18250 elsif Nkind (N) = N_Attribute_Reference then
18252 -- Catch beginner's error (use of attribute other than 'Range)
18254 if Attribute_Name (N) /= Name_Range then
18255 Error_Msg_N ("expect attribute ''Range", N);
18256 Set_Etype (N, Any_Type);
18260 -- If the node denotes the range of a type mark, that is also the
18261 -- resulting type, and we do not need to create an Itype for it.
18263 if Is_Entity_Name (Prefix (N))
18264 and then Comes_From_Source (N)
18265 and then Is_Type (Entity (Prefix (N)))
18266 and then Is_Discrete_Type (Entity (Prefix (N)))
18268 Def_Id := Entity (Prefix (N));
18271 Analyze_And_Resolve (N);
18275 -- If none of the above, must be a subtype. We convert this to a
18276 -- range attribute reference because in the case of declared first
18277 -- named subtypes, the types in the range reference can be different
18278 -- from the type of the entity. A range attribute normalizes the
18279 -- reference and obtains the correct types for the bounds.
18281 -- This transformation is in the nature of an expansion, is only
18282 -- done if expansion is active. In particular, it is not done on
18283 -- formal generic types, because we need to retain the name of the
18284 -- original index for instantiation purposes.
18287 if not Is_Entity_Name (N) or else not Is_Type (Entity (N)) then
18288 Error_Msg_N ("invalid subtype mark in discrete range ", N);
18289 Set_Etype (N, Any_Integer);
18293 -- The type mark may be that of an incomplete type. It is only
18294 -- now that we can get the full view, previous analysis does
18295 -- not look specifically for a type mark.
18297 Set_Entity (N, Get_Full_View (Entity (N)));
18298 Set_Etype (N, Entity (N));
18299 Def_Id := Entity (N);
18301 if not Is_Discrete_Type (Def_Id) then
18302 Error_Msg_N ("discrete type required for index", N);
18303 Set_Etype (N, Any_Type);
18308 if Expander_Active then
18310 Make_Attribute_Reference (Sloc (N),
18311 Attribute_Name => Name_Range,
18312 Prefix => Relocate_Node (N)));
18314 -- The original was a subtype mark that does not freeze. This
18315 -- means that the rewritten version must not freeze either.
18317 Set_Must_Not_Freeze (N);
18318 Set_Must_Not_Freeze (Prefix (N));
18319 Analyze_And_Resolve (N);
18323 -- If expander is inactive, type is legal, nothing else to construct
18330 if not Is_Discrete_Type (T) then
18331 Error_Msg_N ("discrete type required for range", N);
18332 Set_Etype (N, Any_Type);
18335 elsif T = Any_Type then
18336 Set_Etype (N, Any_Type);
18340 -- We will now create the appropriate Itype to describe the range, but
18341 -- first a check. If we originally had a subtype, then we just label
18342 -- the range with this subtype. Not only is there no need to construct
18343 -- a new subtype, but it is wrong to do so for two reasons:
18345 -- 1. A legality concern, if we have a subtype, it must not freeze,
18346 -- and the Itype would cause freezing incorrectly
18348 -- 2. An efficiency concern, if we created an Itype, it would not be
18349 -- recognized as the same type for the purposes of eliminating
18350 -- checks in some circumstances.
18352 -- We signal this case by setting the subtype entity in Def_Id
18354 if No (Def_Id) then
18356 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
18357 Set_Etype (Def_Id, Base_Type (T));
18359 if Is_Signed_Integer_Type (T) then
18360 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
18362 elsif Is_Modular_Integer_Type (T) then
18363 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
18366 Set_Ekind (Def_Id, E_Enumeration_Subtype);
18367 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
18368 Set_First_Literal (Def_Id, First_Literal (T));
18371 Set_Size_Info (Def_Id, (T));
18372 Set_RM_Size (Def_Id, RM_Size (T));
18373 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
18375 Set_Scalar_Range (Def_Id, R);
18376 Conditional_Delay (Def_Id, T);
18378 if Nkind (N) = N_Subtype_Indication then
18379 Inherit_Predicate_Flags (Def_Id, Entity (Subtype_Mark (N)));
18382 -- In the subtype indication case, if the immediate parent of the
18383 -- new subtype is non-static, then the subtype we create is non-
18384 -- static, even if its bounds are static.
18386 if Nkind (N) = N_Subtype_Indication
18387 and then not Is_OK_Static_Subtype (Entity (Subtype_Mark (N)))
18389 Set_Is_Non_Static_Subtype (Def_Id);
18393 -- Final step is to label the index with this constructed type
18395 Set_Etype (N, Def_Id);
18398 ------------------------------
18399 -- Modular_Type_Declaration --
18400 ------------------------------
18402 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
18403 Mod_Expr : constant Node_Id := Expression (Def);
18406 procedure Set_Modular_Size (Bits : Int);
18407 -- Sets RM_Size to Bits, and Esize to normal word size above this
18409 ----------------------
18410 -- Set_Modular_Size --
18411 ----------------------
18413 procedure Set_Modular_Size (Bits : Int) is
18415 Set_RM_Size (T, UI_From_Int (Bits));
18420 elsif Bits <= 16 then
18421 Init_Esize (T, 16);
18423 elsif Bits <= 32 then
18424 Init_Esize (T, 32);
18427 Init_Esize (T, System_Max_Binary_Modulus_Power);
18430 if not Non_Binary_Modulus (T) and then Esize (T) = RM_Size (T) then
18431 Set_Is_Known_Valid (T);
18433 end Set_Modular_Size;
18435 -- Start of processing for Modular_Type_Declaration
18438 -- If the mod expression is (exactly) 2 * literal, where literal is
18439 -- 64 or less,then almost certainly the * was meant to be **. Warn.
18441 if Warn_On_Suspicious_Modulus_Value
18442 and then Nkind (Mod_Expr) = N_Op_Multiply
18443 and then Nkind (Left_Opnd (Mod_Expr)) = N_Integer_Literal
18444 and then Intval (Left_Opnd (Mod_Expr)) = Uint_2
18445 and then Nkind (Right_Opnd (Mod_Expr)) = N_Integer_Literal
18446 and then Intval (Right_Opnd (Mod_Expr)) <= Uint_64
18449 ("suspicious MOD value, was '*'* intended'??M?", Mod_Expr);
18452 -- Proceed with analysis of mod expression
18454 Analyze_And_Resolve (Mod_Expr, Any_Integer);
18456 Set_Ekind (T, E_Modular_Integer_Type);
18457 Init_Alignment (T);
18458 Set_Is_Constrained (T);
18460 if not Is_OK_Static_Expression (Mod_Expr) then
18461 Flag_Non_Static_Expr
18462 ("non-static expression used for modular type bound!", Mod_Expr);
18463 M_Val := 2 ** System_Max_Binary_Modulus_Power;
18465 M_Val := Expr_Value (Mod_Expr);
18469 Error_Msg_N ("modulus value must be positive", Mod_Expr);
18470 M_Val := 2 ** System_Max_Binary_Modulus_Power;
18473 if M_Val > 2 ** Standard_Long_Integer_Size then
18474 Check_Restriction (No_Long_Long_Integers, Mod_Expr);
18477 Set_Modulus (T, M_Val);
18479 -- Create bounds for the modular type based on the modulus given in
18480 -- the type declaration and then analyze and resolve those bounds.
18482 Set_Scalar_Range (T,
18483 Make_Range (Sloc (Mod_Expr),
18484 Low_Bound => Make_Integer_Literal (Sloc (Mod_Expr), 0),
18485 High_Bound => Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
18487 -- Properly analyze the literals for the range. We do this manually
18488 -- because we can't go calling Resolve, since we are resolving these
18489 -- bounds with the type, and this type is certainly not complete yet.
18491 Set_Etype (Low_Bound (Scalar_Range (T)), T);
18492 Set_Etype (High_Bound (Scalar_Range (T)), T);
18493 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
18494 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
18496 -- Loop through powers of two to find number of bits required
18498 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
18502 if M_Val = 2 ** Bits then
18503 Set_Modular_Size (Bits);
18508 elsif M_Val < 2 ** Bits then
18509 Check_SPARK_05_Restriction ("modulus should be a power of 2", T);
18510 Set_Non_Binary_Modulus (T);
18512 if Bits > System_Max_Nonbinary_Modulus_Power then
18513 Error_Msg_Uint_1 :=
18514 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
18516 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
18517 Set_Modular_Size (System_Max_Binary_Modulus_Power);
18521 -- In the nonbinary case, set size as per RM 13.3(55)
18523 Set_Modular_Size (Bits);
18530 -- If we fall through, then the size exceed System.Max_Binary_Modulus
18531 -- so we just signal an error and set the maximum size.
18533 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
18534 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
18536 Set_Modular_Size (System_Max_Binary_Modulus_Power);
18537 Init_Alignment (T);
18539 end Modular_Type_Declaration;
18541 --------------------------
18542 -- New_Concatenation_Op --
18543 --------------------------
18545 procedure New_Concatenation_Op (Typ : Entity_Id) is
18546 Loc : constant Source_Ptr := Sloc (Typ);
18549 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
18550 -- Create abbreviated declaration for the formal of a predefined
18551 -- Operator 'Op' of type 'Typ'
18553 --------------------
18554 -- Make_Op_Formal --
18555 --------------------
18557 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
18558 Formal : Entity_Id;
18560 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
18561 Set_Etype (Formal, Typ);
18562 Set_Mechanism (Formal, Default_Mechanism);
18564 end Make_Op_Formal;
18566 -- Start of processing for New_Concatenation_Op
18569 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
18571 Set_Ekind (Op, E_Operator);
18572 Set_Scope (Op, Current_Scope);
18573 Set_Etype (Op, Typ);
18574 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
18575 Set_Is_Immediately_Visible (Op);
18576 Set_Is_Intrinsic_Subprogram (Op);
18577 Set_Has_Completion (Op);
18578 Append_Entity (Op, Current_Scope);
18580 Set_Name_Entity_Id (Name_Op_Concat, Op);
18582 Append_Entity (Make_Op_Formal (Typ, Op), Op);
18583 Append_Entity (Make_Op_Formal (Typ, Op), Op);
18584 end New_Concatenation_Op;
18586 -------------------------
18587 -- OK_For_Limited_Init --
18588 -------------------------
18590 -- ???Check all calls of this, and compare the conditions under which it's
18593 function OK_For_Limited_Init
18595 Exp : Node_Id) return Boolean
18598 return Is_CPP_Constructor_Call (Exp)
18599 or else (Ada_Version >= Ada_2005
18600 and then not Debug_Flag_Dot_L
18601 and then OK_For_Limited_Init_In_05 (Typ, Exp));
18602 end OK_For_Limited_Init;
18604 -------------------------------
18605 -- OK_For_Limited_Init_In_05 --
18606 -------------------------------
18608 function OK_For_Limited_Init_In_05
18610 Exp : Node_Id) return Boolean
18613 -- An object of a limited interface type can be initialized with any
18614 -- expression of a nonlimited descendant type.
18616 if Is_Class_Wide_Type (Typ)
18617 and then Is_Limited_Interface (Typ)
18618 and then not Is_Limited_Type (Etype (Exp))
18623 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
18624 -- case of limited aggregates (including extension aggregates), and
18625 -- function calls. The function call may have been given in prefixed
18626 -- notation, in which case the original node is an indexed component.
18627 -- If the function is parameterless, the original node was an explicit
18628 -- dereference. The function may also be parameterless, in which case
18629 -- the source node is just an identifier.
18631 -- A branch of a conditional expression may have been removed if the
18632 -- condition is statically known. This happens during expansion, and
18633 -- thus will not happen if previous errors were encountered. The check
18634 -- will have been performed on the chosen branch, which replaces the
18635 -- original conditional expression.
18641 case Nkind (Original_Node (Exp)) is
18642 when N_Aggregate | N_Extension_Aggregate | N_Function_Call | N_Op =>
18645 when N_Identifier =>
18646 return Present (Entity (Original_Node (Exp)))
18647 and then Ekind (Entity (Original_Node (Exp))) = E_Function;
18649 when N_Qualified_Expression =>
18651 OK_For_Limited_Init_In_05
18652 (Typ, Expression (Original_Node (Exp)));
18654 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
18655 -- with a function call, the expander has rewritten the call into an
18656 -- N_Type_Conversion node to force displacement of the pointer to
18657 -- reference the component containing the secondary dispatch table.
18658 -- Otherwise a type conversion is not a legal context.
18659 -- A return statement for a build-in-place function returning a
18660 -- synchronized type also introduces an unchecked conversion.
18662 when N_Type_Conversion |
18663 N_Unchecked_Type_Conversion =>
18664 return not Comes_From_Source (Exp)
18666 OK_For_Limited_Init_In_05
18667 (Typ, Expression (Original_Node (Exp)));
18669 when N_Indexed_Component |
18670 N_Selected_Component |
18671 N_Explicit_Dereference =>
18672 return Nkind (Exp) = N_Function_Call;
18674 -- A use of 'Input is a function call, hence allowed. Normally the
18675 -- attribute will be changed to a call, but the attribute by itself
18676 -- can occur with -gnatc.
18678 when N_Attribute_Reference =>
18679 return Attribute_Name (Original_Node (Exp)) = Name_Input;
18681 -- For a case expression, all dependent expressions must be legal
18683 when N_Case_Expression =>
18688 Alt := First (Alternatives (Original_Node (Exp)));
18689 while Present (Alt) loop
18690 if not OK_For_Limited_Init_In_05 (Typ, Expression (Alt)) then
18700 -- For an if expression, all dependent expressions must be legal
18702 when N_If_Expression =>
18704 Then_Expr : constant Node_Id :=
18705 Next (First (Expressions (Original_Node (Exp))));
18706 Else_Expr : constant Node_Id := Next (Then_Expr);
18708 return OK_For_Limited_Init_In_05 (Typ, Then_Expr)
18710 OK_For_Limited_Init_In_05 (Typ, Else_Expr);
18716 end OK_For_Limited_Init_In_05;
18718 -------------------------------------------
18719 -- Ordinary_Fixed_Point_Type_Declaration --
18720 -------------------------------------------
18722 procedure Ordinary_Fixed_Point_Type_Declaration
18726 Loc : constant Source_Ptr := Sloc (Def);
18727 Delta_Expr : constant Node_Id := Delta_Expression (Def);
18728 RRS : constant Node_Id := Real_Range_Specification (Def);
18729 Implicit_Base : Entity_Id;
18736 Check_Restriction (No_Fixed_Point, Def);
18738 -- Create implicit base type
18741 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
18742 Set_Etype (Implicit_Base, Implicit_Base);
18744 -- Analyze and process delta expression
18746 Analyze_And_Resolve (Delta_Expr, Any_Real);
18748 Check_Delta_Expression (Delta_Expr);
18749 Delta_Val := Expr_Value_R (Delta_Expr);
18751 Set_Delta_Value (Implicit_Base, Delta_Val);
18753 -- Compute default small from given delta, which is the largest power
18754 -- of two that does not exceed the given delta value.
18764 if Delta_Val < Ureal_1 then
18765 while Delta_Val < Tmp loop
18766 Tmp := Tmp / Ureal_2;
18767 Scale := Scale + 1;
18772 Tmp := Tmp * Ureal_2;
18773 exit when Tmp > Delta_Val;
18774 Scale := Scale - 1;
18778 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
18781 Set_Small_Value (Implicit_Base, Small_Val);
18783 -- If no range was given, set a dummy range
18785 if RRS <= Empty_Or_Error then
18786 Low_Val := -Small_Val;
18787 High_Val := Small_Val;
18789 -- Otherwise analyze and process given range
18793 Low : constant Node_Id := Low_Bound (RRS);
18794 High : constant Node_Id := High_Bound (RRS);
18797 Analyze_And_Resolve (Low, Any_Real);
18798 Analyze_And_Resolve (High, Any_Real);
18799 Check_Real_Bound (Low);
18800 Check_Real_Bound (High);
18802 -- Obtain and set the range
18804 Low_Val := Expr_Value_R (Low);
18805 High_Val := Expr_Value_R (High);
18807 if Low_Val > High_Val then
18808 Error_Msg_NE ("??fixed point type& has null range", Def, T);
18813 -- The range for both the implicit base and the declared first subtype
18814 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
18815 -- set a temporary range in place. Note that the bounds of the base
18816 -- type will be widened to be symmetrical and to fill the available
18817 -- bits when the type is frozen.
18819 -- We could do this with all discrete types, and probably should, but
18820 -- we absolutely have to do it for fixed-point, since the end-points
18821 -- of the range and the size are determined by the small value, which
18822 -- could be reset before the freeze point.
18824 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
18825 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
18827 -- Complete definition of first subtype. The inheritance of the rep item
18828 -- chain ensures that SPARK-related pragmas are not clobbered when the
18829 -- ordinary fixed point type acts as a full view of a private type.
18831 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
18832 Set_Etype (T, Implicit_Base);
18833 Init_Size_Align (T);
18834 Inherit_Rep_Item_Chain (T, Implicit_Base);
18835 Set_Small_Value (T, Small_Val);
18836 Set_Delta_Value (T, Delta_Val);
18837 Set_Is_Constrained (T);
18838 end Ordinary_Fixed_Point_Type_Declaration;
18840 ----------------------------------
18841 -- Preanalyze_Assert_Expression --
18842 ----------------------------------
18844 procedure Preanalyze_Assert_Expression (N : Node_Id; T : Entity_Id) is
18846 In_Assertion_Expr := In_Assertion_Expr + 1;
18847 Preanalyze_Spec_Expression (N, T);
18848 In_Assertion_Expr := In_Assertion_Expr - 1;
18849 end Preanalyze_Assert_Expression;
18851 -----------------------------------
18852 -- Preanalyze_Default_Expression --
18853 -----------------------------------
18855 procedure Preanalyze_Default_Expression (N : Node_Id; T : Entity_Id) is
18856 Save_In_Default_Expr : constant Boolean := In_Default_Expr;
18858 In_Default_Expr := True;
18859 Preanalyze_Spec_Expression (N, T);
18860 In_Default_Expr := Save_In_Default_Expr;
18861 end Preanalyze_Default_Expression;
18863 --------------------------------
18864 -- Preanalyze_Spec_Expression --
18865 --------------------------------
18867 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
18868 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
18870 In_Spec_Expression := True;
18871 Preanalyze_And_Resolve (N, T);
18872 In_Spec_Expression := Save_In_Spec_Expression;
18873 end Preanalyze_Spec_Expression;
18875 ----------------------------------------
18876 -- Prepare_Private_Subtype_Completion --
18877 ----------------------------------------
18879 procedure Prepare_Private_Subtype_Completion
18881 Related_Nod : Node_Id)
18883 Id_B : constant Entity_Id := Base_Type (Id);
18884 Full_B : Entity_Id := Full_View (Id_B);
18888 if Present (Full_B) then
18890 -- Get to the underlying full view if necessary
18892 if Is_Private_Type (Full_B)
18893 and then Present (Underlying_Full_View (Full_B))
18895 Full_B := Underlying_Full_View (Full_B);
18898 -- The Base_Type is already completed, we can complete the subtype
18899 -- now. We have to create a new entity with the same name, Thus we
18900 -- can't use Create_Itype.
18902 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
18903 Set_Is_Itype (Full);
18904 Set_Associated_Node_For_Itype (Full, Related_Nod);
18905 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
18908 -- The parent subtype may be private, but the base might not, in some
18909 -- nested instances. In that case, the subtype does not need to be
18910 -- exchanged. It would still be nice to make private subtypes and their
18911 -- bases consistent at all times ???
18913 if Is_Private_Type (Id_B) then
18914 Append_Elmt (Id, Private_Dependents (Id_B));
18916 end Prepare_Private_Subtype_Completion;
18918 ---------------------------
18919 -- Process_Discriminants --
18920 ---------------------------
18922 procedure Process_Discriminants
18924 Prev : Entity_Id := Empty)
18926 Elist : constant Elist_Id := New_Elmt_List;
18929 Discr_Number : Uint;
18930 Discr_Type : Entity_Id;
18931 Default_Present : Boolean := False;
18932 Default_Not_Present : Boolean := False;
18935 -- A composite type other than an array type can have discriminants.
18936 -- On entry, the current scope is the composite type.
18938 -- The discriminants are initially entered into the scope of the type
18939 -- via Enter_Name with the default Ekind of E_Void to prevent premature
18940 -- use, as explained at the end of this procedure.
18942 Discr := First (Discriminant_Specifications (N));
18943 while Present (Discr) loop
18944 Enter_Name (Defining_Identifier (Discr));
18946 -- For navigation purposes we add a reference to the discriminant
18947 -- in the entity for the type. If the current declaration is a
18948 -- completion, place references on the partial view. Otherwise the
18949 -- type is the current scope.
18951 if Present (Prev) then
18953 -- The references go on the partial view, if present. If the
18954 -- partial view has discriminants, the references have been
18955 -- generated already.
18957 if not Has_Discriminants (Prev) then
18958 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
18962 (Current_Scope, Defining_Identifier (Discr), 'd');
18965 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
18966 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
18968 -- Ada 2005 (AI-254)
18970 if Present (Access_To_Subprogram_Definition
18971 (Discriminant_Type (Discr)))
18972 and then Protected_Present (Access_To_Subprogram_Definition
18973 (Discriminant_Type (Discr)))
18976 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
18980 Find_Type (Discriminant_Type (Discr));
18981 Discr_Type := Etype (Discriminant_Type (Discr));
18983 if Error_Posted (Discriminant_Type (Discr)) then
18984 Discr_Type := Any_Type;
18988 -- Handling of discriminants that are access types
18990 if Is_Access_Type (Discr_Type) then
18992 -- Ada 2005 (AI-230): Access discriminant allowed in non-
18993 -- limited record types
18995 if Ada_Version < Ada_2005 then
18996 Check_Access_Discriminant_Requires_Limited
18997 (Discr, Discriminant_Type (Discr));
19000 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
19002 ("(Ada 83) access discriminant not allowed", Discr);
19005 -- If not access type, must be a discrete type
19007 elsif not Is_Discrete_Type (Discr_Type) then
19009 ("discriminants must have a discrete or access type",
19010 Discriminant_Type (Discr));
19013 Set_Etype (Defining_Identifier (Discr), Discr_Type);
19015 -- If a discriminant specification includes the assignment compound
19016 -- delimiter followed by an expression, the expression is the default
19017 -- expression of the discriminant; the default expression must be of
19018 -- the type of the discriminant. (RM 3.7.1) Since this expression is
19019 -- a default expression, we do the special preanalysis, since this
19020 -- expression does not freeze (see section "Handling of Default and
19021 -- Per-Object Expressions" in spec of package Sem).
19023 if Present (Expression (Discr)) then
19024 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
19028 if Nkind (N) = N_Formal_Type_Declaration then
19030 ("discriminant defaults not allowed for formal type",
19031 Expression (Discr));
19033 -- Flag an error for a tagged type with defaulted discriminants,
19034 -- excluding limited tagged types when compiling for Ada 2012
19035 -- (see AI05-0214).
19037 elsif Is_Tagged_Type (Current_Scope)
19038 and then (not Is_Limited_Type (Current_Scope)
19039 or else Ada_Version < Ada_2012)
19040 and then Comes_From_Source (N)
19042 -- Note: see similar test in Check_Or_Process_Discriminants, to
19043 -- handle the (illegal) case of the completion of an untagged
19044 -- view with discriminants with defaults by a tagged full view.
19045 -- We skip the check if Discr does not come from source, to
19046 -- account for the case of an untagged derived type providing
19047 -- defaults for a renamed discriminant from a private untagged
19048 -- ancestor with a tagged full view (ACATS B460006).
19050 if Ada_Version >= Ada_2012 then
19052 ("discriminants of nonlimited tagged type cannot have"
19054 Expression (Discr));
19057 ("discriminants of tagged type cannot have defaults",
19058 Expression (Discr));
19062 Default_Present := True;
19063 Append_Elmt (Expression (Discr), Elist);
19065 -- Tag the defining identifiers for the discriminants with
19066 -- their corresponding default expressions from the tree.
19068 Set_Discriminant_Default_Value
19069 (Defining_Identifier (Discr), Expression (Discr));
19072 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag
19073 -- gets set unless we can be sure that no range check is required.
19075 if (GNATprove_Mode or not Expander_Active)
19078 (Expression (Discr), Discr_Type, Assume_Valid => True)
19080 Set_Do_Range_Check (Expression (Discr));
19083 -- No default discriminant value given
19086 Default_Not_Present := True;
19089 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
19090 -- Discr_Type but with the null-exclusion attribute
19092 if Ada_Version >= Ada_2005 then
19094 -- Ada 2005 (AI-231): Static checks
19096 if Can_Never_Be_Null (Discr_Type) then
19097 Null_Exclusion_Static_Checks (Discr);
19099 elsif Is_Access_Type (Discr_Type)
19100 and then Null_Exclusion_Present (Discr)
19102 -- No need to check itypes because in their case this check
19103 -- was done at their point of creation
19105 and then not Is_Itype (Discr_Type)
19107 if Can_Never_Be_Null (Discr_Type) then
19109 ("`NOT NULL` not allowed (& already excludes null)",
19114 Set_Etype (Defining_Identifier (Discr),
19115 Create_Null_Excluding_Itype
19117 Related_Nod => Discr));
19119 -- Check for improper null exclusion if the type is otherwise
19120 -- legal for a discriminant.
19122 elsif Null_Exclusion_Present (Discr)
19123 and then Is_Discrete_Type (Discr_Type)
19126 ("null exclusion can only apply to an access type", Discr);
19129 -- Ada 2005 (AI-402): access discriminants of nonlimited types
19130 -- can't have defaults. Synchronized types, or types that are
19131 -- explicitly limited are fine, but special tests apply to derived
19132 -- types in generics: in a generic body we have to assume the
19133 -- worst, and therefore defaults are not allowed if the parent is
19134 -- a generic formal private type (see ACATS B370001).
19136 if Is_Access_Type (Discr_Type) and then Default_Present then
19137 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
19138 or else Is_Limited_Record (Current_Scope)
19139 or else Is_Concurrent_Type (Current_Scope)
19140 or else Is_Concurrent_Record_Type (Current_Scope)
19141 or else Ekind (Current_Scope) = E_Limited_Private_Type
19143 if not Is_Derived_Type (Current_Scope)
19144 or else not Is_Generic_Type (Etype (Current_Scope))
19145 or else not In_Package_Body (Scope (Etype (Current_Scope)))
19146 or else Limited_Present
19147 (Type_Definition (Parent (Current_Scope)))
19153 ("access discriminants of nonlimited types cannot "
19154 & "have defaults", Expression (Discr));
19157 elsif Present (Expression (Discr)) then
19159 ("(Ada 2005) access discriminants of nonlimited types "
19160 & "cannot have defaults", Expression (Discr));
19165 -- A discriminant cannot be effectively volatile (SPARK RM 7.1.3(6)).
19166 -- This check is relevant only when SPARK_Mode is on as it is not a
19167 -- standard Ada legality rule.
19170 and then Is_Effectively_Volatile (Defining_Identifier (Discr))
19172 Error_Msg_N ("discriminant cannot be volatile", Discr);
19178 -- An element list consisting of the default expressions of the
19179 -- discriminants is constructed in the above loop and used to set
19180 -- the Discriminant_Constraint attribute for the type. If an object
19181 -- is declared of this (record or task) type without any explicit
19182 -- discriminant constraint given, this element list will form the
19183 -- actual parameters for the corresponding initialization procedure
19186 Set_Discriminant_Constraint (Current_Scope, Elist);
19187 Set_Stored_Constraint (Current_Scope, No_Elist);
19189 -- Default expressions must be provided either for all or for none
19190 -- of the discriminants of a discriminant part. (RM 3.7.1)
19192 if Default_Present and then Default_Not_Present then
19194 ("incomplete specification of defaults for discriminants", N);
19197 -- The use of the name of a discriminant is not allowed in default
19198 -- expressions of a discriminant part if the specification of the
19199 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
19201 -- To detect this, the discriminant names are entered initially with an
19202 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
19203 -- attempt to use a void entity (for example in an expression that is
19204 -- type-checked) produces the error message: premature usage. Now after
19205 -- completing the semantic analysis of the discriminant part, we can set
19206 -- the Ekind of all the discriminants appropriately.
19208 Discr := First (Discriminant_Specifications (N));
19209 Discr_Number := Uint_1;
19210 while Present (Discr) loop
19211 Id := Defining_Identifier (Discr);
19212 Set_Ekind (Id, E_Discriminant);
19213 Init_Component_Location (Id);
19215 Set_Discriminant_Number (Id, Discr_Number);
19217 -- Make sure this is always set, even in illegal programs
19219 Set_Corresponding_Discriminant (Id, Empty);
19221 -- Initialize the Original_Record_Component to the entity itself.
19222 -- Inherit_Components will propagate the right value to
19223 -- discriminants in derived record types.
19225 Set_Original_Record_Component (Id, Id);
19227 -- Create the discriminal for the discriminant
19229 Build_Discriminal (Id);
19232 Discr_Number := Discr_Number + 1;
19235 Set_Has_Discriminants (Current_Scope);
19236 end Process_Discriminants;
19238 -----------------------
19239 -- Process_Full_View --
19240 -----------------------
19242 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
19243 procedure Collect_Implemented_Interfaces
19245 Ifaces : Elist_Id);
19246 -- Ada 2005: Gather all the interfaces that Typ directly or
19247 -- inherently implements. Duplicate entries are not added to
19248 -- the list Ifaces.
19250 ------------------------------------
19251 -- Collect_Implemented_Interfaces --
19252 ------------------------------------
19254 procedure Collect_Implemented_Interfaces
19259 Iface_Elmt : Elmt_Id;
19262 -- Abstract interfaces are only associated with tagged record types
19264 if not Is_Tagged_Type (Typ) or else not Is_Record_Type (Typ) then
19268 -- Recursively climb to the ancestors
19270 if Etype (Typ) /= Typ
19272 -- Protect the frontend against wrong cyclic declarations like:
19274 -- type B is new A with private;
19275 -- type C is new A with private;
19277 -- type B is new C with null record;
19278 -- type C is new B with null record;
19280 and then Etype (Typ) /= Priv_T
19281 and then Etype (Typ) /= Full_T
19283 -- Keep separate the management of private type declarations
19285 if Ekind (Typ) = E_Record_Type_With_Private then
19287 -- Handle the following illegal usage:
19288 -- type Private_Type is tagged private;
19290 -- type Private_Type is new Type_Implementing_Iface;
19292 if Present (Full_View (Typ))
19293 and then Etype (Typ) /= Full_View (Typ)
19295 if Is_Interface (Etype (Typ)) then
19296 Append_Unique_Elmt (Etype (Typ), Ifaces);
19299 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
19302 -- Non-private types
19305 if Is_Interface (Etype (Typ)) then
19306 Append_Unique_Elmt (Etype (Typ), Ifaces);
19309 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
19313 -- Handle entities in the list of abstract interfaces
19315 if Present (Interfaces (Typ)) then
19316 Iface_Elmt := First_Elmt (Interfaces (Typ));
19317 while Present (Iface_Elmt) loop
19318 Iface := Node (Iface_Elmt);
19320 pragma Assert (Is_Interface (Iface));
19322 if not Contain_Interface (Iface, Ifaces) then
19323 Append_Elmt (Iface, Ifaces);
19324 Collect_Implemented_Interfaces (Iface, Ifaces);
19327 Next_Elmt (Iface_Elmt);
19330 end Collect_Implemented_Interfaces;
19334 Full_Indic : Node_Id;
19335 Full_Parent : Entity_Id;
19336 Priv_Parent : Entity_Id;
19338 -- Start of processing for Process_Full_View
19341 -- First some sanity checks that must be done after semantic
19342 -- decoration of the full view and thus cannot be placed with other
19343 -- similar checks in Find_Type_Name
19345 if not Is_Limited_Type (Priv_T)
19346 and then (Is_Limited_Type (Full_T)
19347 or else Is_Limited_Composite (Full_T))
19349 if In_Instance then
19353 ("completion of nonlimited type cannot be limited", Full_T);
19354 Explain_Limited_Type (Full_T, Full_T);
19357 elsif Is_Abstract_Type (Full_T)
19358 and then not Is_Abstract_Type (Priv_T)
19361 ("completion of nonabstract type cannot be abstract", Full_T);
19363 elsif Is_Tagged_Type (Priv_T)
19364 and then Is_Limited_Type (Priv_T)
19365 and then not Is_Limited_Type (Full_T)
19367 -- If pragma CPP_Class was applied to the private declaration
19368 -- propagate the limitedness to the full-view
19370 if Is_CPP_Class (Priv_T) then
19371 Set_Is_Limited_Record (Full_T);
19373 -- GNAT allow its own definition of Limited_Controlled to disobey
19374 -- this rule in order in ease the implementation. This test is safe
19375 -- because Root_Controlled is defined in a child of System that
19376 -- normal programs are not supposed to use.
19378 elsif Is_RTE (Etype (Full_T), RE_Root_Controlled) then
19379 Set_Is_Limited_Composite (Full_T);
19382 ("completion of limited tagged type must be limited", Full_T);
19385 elsif Is_Generic_Type (Priv_T) then
19386 Error_Msg_N ("generic type cannot have a completion", Full_T);
19389 -- Check that ancestor interfaces of private and full views are
19390 -- consistent. We omit this check for synchronized types because
19391 -- they are performed on the corresponding record type when frozen.
19393 if Ada_Version >= Ada_2005
19394 and then Is_Tagged_Type (Priv_T)
19395 and then Is_Tagged_Type (Full_T)
19396 and then not Is_Concurrent_Type (Full_T)
19400 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
19401 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
19404 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
19405 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
19407 -- Ada 2005 (AI-251): The partial view shall be a descendant of
19408 -- an interface type if and only if the full type is descendant
19409 -- of the interface type (AARM 7.3 (7.3/2)).
19411 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
19413 if Present (Iface) then
19415 ("interface in partial view& not implemented by full type "
19416 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
19419 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
19421 if Present (Iface) then
19423 ("interface & not implemented by partial view "
19424 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
19429 if Is_Tagged_Type (Priv_T)
19430 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19431 and then Is_Derived_Type (Full_T)
19433 Priv_Parent := Etype (Priv_T);
19435 -- The full view of a private extension may have been transformed
19436 -- into an unconstrained derived type declaration and a subtype
19437 -- declaration (see build_derived_record_type for details).
19439 if Nkind (N) = N_Subtype_Declaration then
19440 Full_Indic := Subtype_Indication (N);
19441 Full_Parent := Etype (Base_Type (Full_T));
19443 Full_Indic := Subtype_Indication (Type_Definition (N));
19444 Full_Parent := Etype (Full_T);
19447 -- Check that the parent type of the full type is a descendant of
19448 -- the ancestor subtype given in the private extension. If either
19449 -- entity has an Etype equal to Any_Type then we had some previous
19450 -- error situation [7.3(8)].
19452 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
19455 -- Ada 2005 (AI-251): Interfaces in the full type can be given in
19456 -- any order. Therefore we don't have to check that its parent must
19457 -- be a descendant of the parent of the private type declaration.
19459 elsif Is_Interface (Priv_Parent)
19460 and then Is_Interface (Full_Parent)
19464 -- Ada 2005 (AI-251): If the parent of the private type declaration
19465 -- is an interface there is no need to check that it is an ancestor
19466 -- of the associated full type declaration. The required tests for
19467 -- this case are performed by Build_Derived_Record_Type.
19469 elsif not Is_Interface (Base_Type (Priv_Parent))
19470 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
19473 ("parent of full type must descend from parent"
19474 & " of private extension", Full_Indic);
19476 -- First check a formal restriction, and then proceed with checking
19477 -- Ada rules. Since the formal restriction is not a serious error, we
19478 -- don't prevent further error detection for this check, hence the
19482 -- In formal mode, when completing a private extension the type
19483 -- named in the private part must be exactly the same as that
19484 -- named in the visible part.
19486 if Priv_Parent /= Full_Parent then
19487 Error_Msg_Name_1 := Chars (Priv_Parent);
19488 Check_SPARK_05_Restriction ("% expected", Full_Indic);
19491 -- Check the rules of 7.3(10): if the private extension inherits
19492 -- known discriminants, then the full type must also inherit those
19493 -- discriminants from the same (ancestor) type, and the parent
19494 -- subtype of the full type must be constrained if and only if
19495 -- the ancestor subtype of the private extension is constrained.
19497 if No (Discriminant_Specifications (Parent (Priv_T)))
19498 and then not Has_Unknown_Discriminants (Priv_T)
19499 and then Has_Discriminants (Base_Type (Priv_Parent))
19502 Priv_Indic : constant Node_Id :=
19503 Subtype_Indication (Parent (Priv_T));
19505 Priv_Constr : constant Boolean :=
19506 Is_Constrained (Priv_Parent)
19508 Nkind (Priv_Indic) = N_Subtype_Indication
19510 Is_Constrained (Entity (Priv_Indic));
19512 Full_Constr : constant Boolean :=
19513 Is_Constrained (Full_Parent)
19515 Nkind (Full_Indic) = N_Subtype_Indication
19517 Is_Constrained (Entity (Full_Indic));
19519 Priv_Discr : Entity_Id;
19520 Full_Discr : Entity_Id;
19523 Priv_Discr := First_Discriminant (Priv_Parent);
19524 Full_Discr := First_Discriminant (Full_Parent);
19525 while Present (Priv_Discr) and then Present (Full_Discr) loop
19526 if Original_Record_Component (Priv_Discr) =
19527 Original_Record_Component (Full_Discr)
19529 Corresponding_Discriminant (Priv_Discr) =
19530 Corresponding_Discriminant (Full_Discr)
19537 Next_Discriminant (Priv_Discr);
19538 Next_Discriminant (Full_Discr);
19541 if Present (Priv_Discr) or else Present (Full_Discr) then
19543 ("full view must inherit discriminants of the parent"
19544 & " type used in the private extension", Full_Indic);
19546 elsif Priv_Constr and then not Full_Constr then
19548 ("parent subtype of full type must be constrained",
19551 elsif Full_Constr and then not Priv_Constr then
19553 ("parent subtype of full type must be unconstrained",
19558 -- Check the rules of 7.3(12): if a partial view has neither
19559 -- known or unknown discriminants, then the full type
19560 -- declaration shall define a definite subtype.
19562 elsif not Has_Unknown_Discriminants (Priv_T)
19563 and then not Has_Discriminants (Priv_T)
19564 and then not Is_Constrained (Full_T)
19567 ("full view must define a constrained type if partial view"
19568 & " has no discriminants", Full_T);
19571 -- ??????? Do we implement the following properly ?????
19572 -- If the ancestor subtype of a private extension has constrained
19573 -- discriminants, then the parent subtype of the full view shall
19574 -- impose a statically matching constraint on those discriminants
19579 -- For untagged types, verify that a type without discriminants is
19580 -- not completed with an unconstrained type. A separate error message
19581 -- is produced if the full type has defaulted discriminants.
19583 if Is_Definite_Subtype (Priv_T)
19584 and then not Is_Definite_Subtype (Full_T)
19586 Error_Msg_Sloc := Sloc (Parent (Priv_T));
19588 ("full view of& not compatible with declaration#",
19591 if not Is_Tagged_Type (Full_T) then
19593 ("\one is constrained, the other unconstrained", Full_T);
19598 -- AI-419: verify that the use of "limited" is consistent
19601 Orig_Decl : constant Node_Id := Original_Node (N);
19604 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19605 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
19607 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
19609 if not Limited_Present (Parent (Priv_T))
19610 and then not Synchronized_Present (Parent (Priv_T))
19611 and then Limited_Present (Type_Definition (Orig_Decl))
19614 ("full view of non-limited extension cannot be limited", N);
19616 -- Conversely, if the partial view carries the limited keyword,
19617 -- the full view must as well, even if it may be redundant.
19619 elsif Limited_Present (Parent (Priv_T))
19620 and then not Limited_Present (Type_Definition (Orig_Decl))
19623 ("full view of limited extension must be explicitly limited",
19629 -- Ada 2005 (AI-443): A synchronized private extension must be
19630 -- completed by a task or protected type.
19632 if Ada_Version >= Ada_2005
19633 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19634 and then Synchronized_Present (Parent (Priv_T))
19635 and then not Is_Concurrent_Type (Full_T)
19637 Error_Msg_N ("full view of synchronized extension must " &
19638 "be synchronized type", N);
19641 -- Ada 2005 AI-363: if the full view has discriminants with
19642 -- defaults, it is illegal to declare constrained access subtypes
19643 -- whose designated type is the current type. This allows objects
19644 -- of the type that are declared in the heap to be unconstrained.
19646 if not Has_Unknown_Discriminants (Priv_T)
19647 and then not Has_Discriminants (Priv_T)
19648 and then Has_Discriminants (Full_T)
19650 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
19652 Set_Has_Constrained_Partial_View (Full_T);
19653 Set_Has_Constrained_Partial_View (Priv_T);
19656 -- Create a full declaration for all its subtypes recorded in
19657 -- Private_Dependents and swap them similarly to the base type. These
19658 -- are subtypes that have been define before the full declaration of
19659 -- the private type. We also swap the entry in Private_Dependents list
19660 -- so we can properly restore the private view on exit from the scope.
19663 Priv_Elmt : Elmt_Id;
19664 Priv_Scop : Entity_Id;
19669 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
19670 while Present (Priv_Elmt) loop
19671 Priv := Node (Priv_Elmt);
19672 Priv_Scop := Scope (Priv);
19674 if Ekind_In (Priv, E_Private_Subtype,
19675 E_Limited_Private_Subtype,
19676 E_Record_Subtype_With_Private)
19678 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
19679 Set_Is_Itype (Full);
19680 Set_Parent (Full, Parent (Priv));
19681 Set_Associated_Node_For_Itype (Full, N);
19683 -- Now we need to complete the private subtype, but since the
19684 -- base type has already been swapped, we must also swap the
19685 -- subtypes (and thus, reverse the arguments in the call to
19686 -- Complete_Private_Subtype). Also note that we may need to
19687 -- re-establish the scope of the private subtype.
19689 Copy_And_Swap (Priv, Full);
19691 if not In_Open_Scopes (Priv_Scop) then
19692 Push_Scope (Priv_Scop);
19695 -- Reset Priv_Scop to Empty to indicate no scope was pushed
19697 Priv_Scop := Empty;
19700 Complete_Private_Subtype (Full, Priv, Full_T, N);
19702 if Present (Priv_Scop) then
19706 Replace_Elmt (Priv_Elmt, Full);
19709 Next_Elmt (Priv_Elmt);
19713 -- If the private view was tagged, copy the new primitive operations
19714 -- from the private view to the full view.
19716 if Is_Tagged_Type (Full_T) then
19718 Disp_Typ : Entity_Id;
19719 Full_List : Elist_Id;
19721 Prim_Elmt : Elmt_Id;
19722 Priv_List : Elist_Id;
19726 L : Elist_Id) return Boolean;
19727 -- Determine whether list L contains element E
19735 L : Elist_Id) return Boolean
19737 List_Elmt : Elmt_Id;
19740 List_Elmt := First_Elmt (L);
19741 while Present (List_Elmt) loop
19742 if Node (List_Elmt) = E then
19746 Next_Elmt (List_Elmt);
19752 -- Start of processing
19755 if Is_Tagged_Type (Priv_T) then
19756 Priv_List := Primitive_Operations (Priv_T);
19757 Prim_Elmt := First_Elmt (Priv_List);
19759 -- In the case of a concurrent type completing a private tagged
19760 -- type, primitives may have been declared in between the two
19761 -- views. These subprograms need to be wrapped the same way
19762 -- entries and protected procedures are handled because they
19763 -- cannot be directly shared by the two views.
19765 if Is_Concurrent_Type (Full_T) then
19767 Conc_Typ : constant Entity_Id :=
19768 Corresponding_Record_Type (Full_T);
19769 Curr_Nod : Node_Id := Parent (Conc_Typ);
19770 Wrap_Spec : Node_Id;
19773 while Present (Prim_Elmt) loop
19774 Prim := Node (Prim_Elmt);
19776 if Comes_From_Source (Prim)
19777 and then not Is_Abstract_Subprogram (Prim)
19780 Make_Subprogram_Declaration (Sloc (Prim),
19784 Obj_Typ => Conc_Typ,
19786 Parameter_Specifications (
19789 Insert_After (Curr_Nod, Wrap_Spec);
19790 Curr_Nod := Wrap_Spec;
19792 Analyze (Wrap_Spec);
19795 Next_Elmt (Prim_Elmt);
19801 -- For non-concurrent types, transfer explicit primitives, but
19802 -- omit those inherited from the parent of the private view
19803 -- since they will be re-inherited later on.
19806 Full_List := Primitive_Operations (Full_T);
19808 while Present (Prim_Elmt) loop
19809 Prim := Node (Prim_Elmt);
19811 if Comes_From_Source (Prim)
19812 and then not Contains (Prim, Full_List)
19814 Append_Elmt (Prim, Full_List);
19817 Next_Elmt (Prim_Elmt);
19821 -- Untagged private view
19824 Full_List := Primitive_Operations (Full_T);
19826 -- In this case the partial view is untagged, so here we locate
19827 -- all of the earlier primitives that need to be treated as
19828 -- dispatching (those that appear between the two views). Note
19829 -- that these additional operations must all be new operations
19830 -- (any earlier operations that override inherited operations
19831 -- of the full view will already have been inserted in the
19832 -- primitives list, marked by Check_Operation_From_Private_View
19833 -- as dispatching. Note that implicit "/=" operators are
19834 -- excluded from being added to the primitives list since they
19835 -- shouldn't be treated as dispatching (tagged "/=" is handled
19838 Prim := Next_Entity (Full_T);
19839 while Present (Prim) and then Prim /= Priv_T loop
19840 if Ekind_In (Prim, E_Procedure, E_Function) then
19841 Disp_Typ := Find_Dispatching_Type (Prim);
19843 if Disp_Typ = Full_T
19844 and then (Chars (Prim) /= Name_Op_Ne
19845 or else Comes_From_Source (Prim))
19847 Check_Controlling_Formals (Full_T, Prim);
19849 if not Is_Dispatching_Operation (Prim) then
19850 Append_Elmt (Prim, Full_List);
19851 Set_Is_Dispatching_Operation (Prim, True);
19852 Set_DT_Position_Value (Prim, No_Uint);
19855 elsif Is_Dispatching_Operation (Prim)
19856 and then Disp_Typ /= Full_T
19859 -- Verify that it is not otherwise controlled by a
19860 -- formal or a return value of type T.
19862 Check_Controlling_Formals (Disp_Typ, Prim);
19866 Next_Entity (Prim);
19870 -- For the tagged case, the two views can share the same primitive
19871 -- operations list and the same class-wide type. Update attributes
19872 -- of the class-wide type which depend on the full declaration.
19874 if Is_Tagged_Type (Priv_T) then
19875 Set_Direct_Primitive_Operations (Priv_T, Full_List);
19876 Set_Class_Wide_Type
19877 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
19879 Set_Has_Task (Class_Wide_Type (Priv_T), Has_Task (Full_T));
19881 (Class_Wide_Type (Priv_T), Has_Protected (Full_T));
19886 -- Ada 2005 AI 161: Check preelaborable initialization consistency
19888 if Known_To_Have_Preelab_Init (Priv_T) then
19890 -- Case where there is a pragma Preelaborable_Initialization. We
19891 -- always allow this in predefined units, which is cheating a bit,
19892 -- but it means we don't have to struggle to meet the requirements in
19893 -- the RM for having Preelaborable Initialization. Otherwise we
19894 -- require that the type meets the RM rules. But we can't check that
19895 -- yet, because of the rule about overriding Initialize, so we simply
19896 -- set a flag that will be checked at freeze time.
19898 if not In_Predefined_Unit (Full_T) then
19899 Set_Must_Have_Preelab_Init (Full_T);
19903 -- If pragma CPP_Class was applied to the private type declaration,
19904 -- propagate it now to the full type declaration.
19906 if Is_CPP_Class (Priv_T) then
19907 Set_Is_CPP_Class (Full_T);
19908 Set_Convention (Full_T, Convention_CPP);
19910 -- Check that components of imported CPP types do not have default
19913 Check_CPP_Type_Has_No_Defaults (Full_T);
19916 -- If the private view has user specified stream attributes, then so has
19919 -- Why the test, how could these flags be already set in Full_T ???
19921 if Has_Specified_Stream_Read (Priv_T) then
19922 Set_Has_Specified_Stream_Read (Full_T);
19925 if Has_Specified_Stream_Write (Priv_T) then
19926 Set_Has_Specified_Stream_Write (Full_T);
19929 if Has_Specified_Stream_Input (Priv_T) then
19930 Set_Has_Specified_Stream_Input (Full_T);
19933 if Has_Specified_Stream_Output (Priv_T) then
19934 Set_Has_Specified_Stream_Output (Full_T);
19937 -- Propagate the attributes related to pragma Default_Initial_Condition
19938 -- from the private to the full view. Note that both flags are mutually
19941 if Has_Default_Init_Cond (Priv_T)
19942 or else Has_Inherited_Default_Init_Cond (Priv_T)
19944 Propagate_Default_Init_Cond_Attributes
19945 (From_Typ => Priv_T,
19947 Private_To_Full_View => True);
19949 -- In the case where the full view is derived from another private type,
19950 -- the attributes related to pragma Default_Initial_Condition must be
19951 -- propagated from the full to the private view to maintain consistency
19955 -- type Parent_Typ is private
19956 -- with Default_Initial_Condition ...;
19958 -- type Parent_Typ is ...;
19961 -- with Pack; use Pack;
19962 -- package Pack_2 is
19963 -- type Deriv_Typ is private; -- must inherit
19965 -- type Deriv_Typ is new Parent_Typ; -- must inherit
19968 elsif Has_Default_Init_Cond (Full_T)
19969 or else Has_Inherited_Default_Init_Cond (Full_T)
19971 Propagate_Default_Init_Cond_Attributes
19972 (From_Typ => Full_T,
19974 Private_To_Full_View => True);
19977 if Is_Ghost_Entity (Priv_T) then
19979 -- The Ghost policy in effect at the point of declaration and at the
19980 -- point of completion must match (SPARK RM 6.9(14)).
19982 Check_Ghost_Completion (Priv_T, Full_T);
19984 -- In the case where the private view of a tagged type lacks a parent
19985 -- type and is subject to pragma Ghost, ensure that the parent type
19986 -- specified by the full view is also Ghost (SPARK RM 6.9(9)).
19988 if Is_Derived_Type (Full_T) then
19989 Check_Ghost_Derivation (Full_T);
19992 -- Propagate the attributes related to pragma Ghost from the private
19993 -- to the full view.
19995 Mark_Full_View_As_Ghost (Priv_T, Full_T);
19998 -- Propagate invariants to full type
20000 if Has_Invariants (Priv_T) then
20001 Set_Has_Invariants (Full_T);
20002 Set_Invariant_Procedure (Full_T, Invariant_Procedure (Priv_T));
20005 if Has_Inheritable_Invariants (Priv_T) then
20006 Set_Has_Inheritable_Invariants (Full_T);
20009 -- Check hidden inheritance of class-wide type invariants
20011 if Ada_Version >= Ada_2012
20012 and then not Has_Inheritable_Invariants (Full_T)
20013 and then In_Private_Part (Current_Scope)
20014 and then Has_Interfaces (Full_T)
20021 Collect_Interfaces (Full_T, Ifaces, Exclude_Parents => True);
20023 AI := First_Elmt (Ifaces);
20024 while Present (AI) loop
20025 if Has_Inheritable_Invariants (Node (AI)) then
20027 ("hidden inheritance of class-wide type invariants " &
20037 -- Propagate predicates to full type, and predicate function if already
20038 -- defined. It is not clear that this can actually happen? the partial
20039 -- view cannot be frozen yet, and the predicate function has not been
20040 -- built. Still it is a cheap check and seems safer to make it.
20042 if Has_Predicates (Priv_T) then
20043 if Present (Predicate_Function (Priv_T)) then
20044 Set_Predicate_Function (Full_T, Predicate_Function (Priv_T));
20047 Set_Has_Predicates (Full_T);
20049 end Process_Full_View;
20051 -----------------------------------
20052 -- Process_Incomplete_Dependents --
20053 -----------------------------------
20055 procedure Process_Incomplete_Dependents
20057 Full_T : Entity_Id;
20060 Inc_Elmt : Elmt_Id;
20061 Priv_Dep : Entity_Id;
20062 New_Subt : Entity_Id;
20064 Disc_Constraint : Elist_Id;
20067 if No (Private_Dependents (Inc_T)) then
20071 -- Itypes that may be generated by the completion of an incomplete
20072 -- subtype are not used by the back-end and not attached to the tree.
20073 -- They are created only for constraint-checking purposes.
20075 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
20076 while Present (Inc_Elmt) loop
20077 Priv_Dep := Node (Inc_Elmt);
20079 if Ekind (Priv_Dep) = E_Subprogram_Type then
20081 -- An Access_To_Subprogram type may have a return type or a
20082 -- parameter type that is incomplete. Replace with the full view.
20084 if Etype (Priv_Dep) = Inc_T then
20085 Set_Etype (Priv_Dep, Full_T);
20089 Formal : Entity_Id;
20092 Formal := First_Formal (Priv_Dep);
20093 while Present (Formal) loop
20094 if Etype (Formal) = Inc_T then
20095 Set_Etype (Formal, Full_T);
20098 Next_Formal (Formal);
20102 elsif Is_Overloadable (Priv_Dep) then
20104 -- If a subprogram in the incomplete dependents list is primitive
20105 -- for a tagged full type then mark it as a dispatching operation,
20106 -- check whether it overrides an inherited subprogram, and check
20107 -- restrictions on its controlling formals. Note that a protected
20108 -- operation is never dispatching: only its wrapper operation
20109 -- (which has convention Ada) is.
20111 if Is_Tagged_Type (Full_T)
20112 and then Is_Primitive (Priv_Dep)
20113 and then Convention (Priv_Dep) /= Convention_Protected
20115 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
20116 Set_Is_Dispatching_Operation (Priv_Dep);
20117 Check_Controlling_Formals (Full_T, Priv_Dep);
20120 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
20122 -- Can happen during processing of a body before the completion
20123 -- of a TA type. Ignore, because spec is also on dependent list.
20127 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
20128 -- corresponding subtype of the full view.
20130 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype then
20131 Set_Subtype_Indication
20132 (Parent (Priv_Dep), New_Occurrence_Of (Full_T, Sloc (Priv_Dep)));
20133 Set_Etype (Priv_Dep, Full_T);
20134 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
20135 Set_Analyzed (Parent (Priv_Dep), False);
20137 -- Reanalyze the declaration, suppressing the call to
20138 -- Enter_Name to avoid duplicate names.
20140 Analyze_Subtype_Declaration
20141 (N => Parent (Priv_Dep),
20144 -- Dependent is a subtype
20147 -- We build a new subtype indication using the full view of the
20148 -- incomplete parent. The discriminant constraints have been
20149 -- elaborated already at the point of the subtype declaration.
20151 New_Subt := Create_Itype (E_Void, N);
20153 if Has_Discriminants (Full_T) then
20154 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
20156 Disc_Constraint := No_Elist;
20159 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
20160 Set_Full_View (Priv_Dep, New_Subt);
20163 Next_Elmt (Inc_Elmt);
20165 end Process_Incomplete_Dependents;
20167 --------------------------------
20168 -- Process_Range_Expr_In_Decl --
20169 --------------------------------
20171 procedure Process_Range_Expr_In_Decl
20174 Subtyp : Entity_Id := Empty;
20175 Check_List : List_Id := Empty_List;
20176 R_Check_Off : Boolean := False;
20177 In_Iter_Schm : Boolean := False)
20180 R_Checks : Check_Result;
20181 Insert_Node : Node_Id;
20182 Def_Id : Entity_Id;
20185 Analyze_And_Resolve (R, Base_Type (T));
20187 if Nkind (R) = N_Range then
20189 -- In SPARK, all ranges should be static, with the exception of the
20190 -- discrete type definition of a loop parameter specification.
20192 if not In_Iter_Schm
20193 and then not Is_OK_Static_Range (R)
20195 Check_SPARK_05_Restriction ("range should be static", R);
20198 Lo := Low_Bound (R);
20199 Hi := High_Bound (R);
20201 -- Validity checks on the range of a quantified expression are
20202 -- delayed until the construct is transformed into a loop.
20204 if Nkind (Parent (R)) = N_Loop_Parameter_Specification
20205 and then Nkind (Parent (Parent (R))) = N_Quantified_Expression
20209 -- We need to ensure validity of the bounds here, because if we
20210 -- go ahead and do the expansion, then the expanded code will get
20211 -- analyzed with range checks suppressed and we miss the check.
20213 -- WARNING: The capture of the range bounds with xxx_FIRST/_LAST and
20214 -- the temporaries generated by routine Remove_Side_Effects by means
20215 -- of validity checks must use the same names. When a range appears
20216 -- in the parent of a generic, the range is processed with checks
20217 -- disabled as part of the generic context and with checks enabled
20218 -- for code generation purposes. This leads to link issues as the
20219 -- generic contains references to xxx_FIRST/_LAST, but the inlined
20220 -- template sees the temporaries generated by Remove_Side_Effects.
20223 Validity_Check_Range (R, Subtyp);
20226 -- If there were errors in the declaration, try and patch up some
20227 -- common mistakes in the bounds. The cases handled are literals
20228 -- which are Integer where the expected type is Real and vice versa.
20229 -- These corrections allow the compilation process to proceed further
20230 -- along since some basic assumptions of the format of the bounds
20233 if Etype (R) = Any_Type then
20234 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
20236 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
20238 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
20240 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
20242 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
20244 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
20246 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
20248 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
20255 -- If the bounds of the range have been mistakenly given as string
20256 -- literals (perhaps in place of character literals), then an error
20257 -- has already been reported, but we rewrite the string literal as a
20258 -- bound of the range's type to avoid blowups in later processing
20259 -- that looks at static values.
20261 if Nkind (Lo) = N_String_Literal then
20263 Make_Attribute_Reference (Sloc (Lo),
20264 Prefix => New_Occurrence_Of (T, Sloc (Lo)),
20265 Attribute_Name => Name_First));
20266 Analyze_And_Resolve (Lo);
20269 if Nkind (Hi) = N_String_Literal then
20271 Make_Attribute_Reference (Sloc (Hi),
20272 Prefix => New_Occurrence_Of (T, Sloc (Hi)),
20273 Attribute_Name => Name_First));
20274 Analyze_And_Resolve (Hi);
20277 -- If bounds aren't scalar at this point then exit, avoiding
20278 -- problems with further processing of the range in this procedure.
20280 if not Is_Scalar_Type (Etype (Lo)) then
20284 -- Resolve (actually Sem_Eval) has checked that the bounds are in
20285 -- then range of the base type. Here we check whether the bounds
20286 -- are in the range of the subtype itself. Note that if the bounds
20287 -- represent the null range the Constraint_Error exception should
20290 -- ??? The following code should be cleaned up as follows
20292 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
20293 -- is done in the call to Range_Check (R, T); below
20295 -- 2. The use of R_Check_Off should be investigated and possibly
20296 -- removed, this would clean up things a bit.
20298 if Is_Null_Range (Lo, Hi) then
20302 -- Capture values of bounds and generate temporaries for them
20303 -- if needed, before applying checks, since checks may cause
20304 -- duplication of the expression without forcing evaluation.
20306 -- The forced evaluation removes side effects from expressions,
20307 -- which should occur also in GNATprove mode. Otherwise, we end up
20308 -- with unexpected insertions of actions at places where this is
20309 -- not supposed to occur, e.g. on default parameters of a call.
20311 if Expander_Active or GNATprove_Mode then
20313 -- Call Force_Evaluation to create declarations as needed to
20314 -- deal with side effects, and also create typ_FIRST/LAST
20315 -- entities for bounds if we have a subtype name.
20317 -- Note: we do this transformation even if expansion is not
20318 -- active if we are in GNATprove_Mode since the transformation
20319 -- is in general required to ensure that the resulting tree has
20320 -- proper Ada semantics.
20323 (Lo, Related_Id => Subtyp, Is_Low_Bound => True);
20325 (Hi, Related_Id => Subtyp, Is_High_Bound => True);
20328 -- We use a flag here instead of suppressing checks on the type
20329 -- because the type we check against isn't necessarily the place
20330 -- where we put the check.
20332 if not R_Check_Off then
20333 R_Checks := Get_Range_Checks (R, T);
20335 -- Look up tree to find an appropriate insertion point. We
20336 -- can't just use insert_actions because later processing
20337 -- depends on the insertion node. Prior to Ada 2012 the
20338 -- insertion point could only be a declaration or a loop, but
20339 -- quantified expressions can appear within any context in an
20340 -- expression, and the insertion point can be any statement,
20341 -- pragma, or declaration.
20343 Insert_Node := Parent (R);
20344 while Present (Insert_Node) loop
20346 Nkind (Insert_Node) in N_Declaration
20349 (Insert_Node, N_Component_Declaration,
20350 N_Loop_Parameter_Specification,
20351 N_Function_Specification,
20352 N_Procedure_Specification);
20354 exit when Nkind (Insert_Node) in N_Later_Decl_Item
20355 or else Nkind (Insert_Node) in
20356 N_Statement_Other_Than_Procedure_Call
20357 or else Nkind_In (Insert_Node, N_Procedure_Call_Statement,
20360 Insert_Node := Parent (Insert_Node);
20363 -- Why would Type_Decl not be present??? Without this test,
20364 -- short regression tests fail.
20366 if Present (Insert_Node) then
20368 -- Case of loop statement. Verify that the range is part
20369 -- of the subtype indication of the iteration scheme.
20371 if Nkind (Insert_Node) = N_Loop_Statement then
20376 Indic := Parent (R);
20377 while Present (Indic)
20378 and then Nkind (Indic) /= N_Subtype_Indication
20380 Indic := Parent (Indic);
20383 if Present (Indic) then
20384 Def_Id := Etype (Subtype_Mark (Indic));
20386 Insert_Range_Checks
20390 Sloc (Insert_Node),
20392 Do_Before => True);
20396 -- Insertion before a declaration. If the declaration
20397 -- includes discriminants, the list of applicable checks
20398 -- is given by the caller.
20400 elsif Nkind (Insert_Node) in N_Declaration then
20401 Def_Id := Defining_Identifier (Insert_Node);
20403 if (Ekind (Def_Id) = E_Record_Type
20404 and then Depends_On_Discriminant (R))
20406 (Ekind (Def_Id) = E_Protected_Type
20407 and then Has_Discriminants (Def_Id))
20409 Append_Range_Checks
20411 Check_List, Def_Id, Sloc (Insert_Node), R);
20414 Insert_Range_Checks
20416 Insert_Node, Def_Id, Sloc (Insert_Node), R);
20420 -- Insertion before a statement. Range appears in the
20421 -- context of a quantified expression. Insertion will
20422 -- take place when expression is expanded.
20431 -- Case of other than an explicit N_Range node
20433 -- The forced evaluation removes side effects from expressions, which
20434 -- should occur also in GNATprove mode. Otherwise, we end up with
20435 -- unexpected insertions of actions at places where this is not
20436 -- supposed to occur, e.g. on default parameters of a call.
20438 elsif Expander_Active or GNATprove_Mode then
20439 Get_Index_Bounds (R, Lo, Hi);
20440 Force_Evaluation (Lo);
20441 Force_Evaluation (Hi);
20443 end Process_Range_Expr_In_Decl;
20445 --------------------------------------
20446 -- Process_Real_Range_Specification --
20447 --------------------------------------
20449 procedure Process_Real_Range_Specification (Def : Node_Id) is
20450 Spec : constant Node_Id := Real_Range_Specification (Def);
20453 Err : Boolean := False;
20455 procedure Analyze_Bound (N : Node_Id);
20456 -- Analyze and check one bound
20458 -------------------
20459 -- Analyze_Bound --
20460 -------------------
20462 procedure Analyze_Bound (N : Node_Id) is
20464 Analyze_And_Resolve (N, Any_Real);
20466 if not Is_OK_Static_Expression (N) then
20467 Flag_Non_Static_Expr
20468 ("bound in real type definition is not static!", N);
20473 -- Start of processing for Process_Real_Range_Specification
20476 if Present (Spec) then
20477 Lo := Low_Bound (Spec);
20478 Hi := High_Bound (Spec);
20479 Analyze_Bound (Lo);
20480 Analyze_Bound (Hi);
20482 -- If error, clear away junk range specification
20485 Set_Real_Range_Specification (Def, Empty);
20488 end Process_Real_Range_Specification;
20490 ---------------------
20491 -- Process_Subtype --
20492 ---------------------
20494 function Process_Subtype
20496 Related_Nod : Node_Id;
20497 Related_Id : Entity_Id := Empty;
20498 Suffix : Character := ' ') return Entity_Id
20501 Def_Id : Entity_Id;
20502 Error_Node : Node_Id;
20503 Full_View_Id : Entity_Id;
20504 Subtype_Mark_Id : Entity_Id;
20506 May_Have_Null_Exclusion : Boolean;
20508 procedure Check_Incomplete (T : Entity_Id);
20509 -- Called to verify that an incomplete type is not used prematurely
20511 ----------------------
20512 -- Check_Incomplete --
20513 ----------------------
20515 procedure Check_Incomplete (T : Entity_Id) is
20517 -- Ada 2005 (AI-412): Incomplete subtypes are legal
20519 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
20521 not (Ada_Version >= Ada_2005
20523 (Nkind (Parent (T)) = N_Subtype_Declaration
20524 or else (Nkind (Parent (T)) = N_Subtype_Indication
20525 and then Nkind (Parent (Parent (T))) =
20526 N_Subtype_Declaration)))
20528 Error_Msg_N ("invalid use of type before its full declaration", T);
20530 end Check_Incomplete;
20532 -- Start of processing for Process_Subtype
20535 -- Case of no constraints present
20537 if Nkind (S) /= N_Subtype_Indication then
20539 Check_Incomplete (S);
20542 -- Ada 2005 (AI-231): Static check
20544 if Ada_Version >= Ada_2005
20545 and then Present (P)
20546 and then Null_Exclusion_Present (P)
20547 and then Nkind (P) /= N_Access_To_Object_Definition
20548 and then not Is_Access_Type (Entity (S))
20550 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
20553 -- The following is ugly, can't we have a range or even a flag???
20555 May_Have_Null_Exclusion :=
20556 Nkind_In (P, N_Access_Definition,
20557 N_Access_Function_Definition,
20558 N_Access_Procedure_Definition,
20559 N_Access_To_Object_Definition,
20561 N_Component_Definition)
20563 Nkind_In (P, N_Derived_Type_Definition,
20564 N_Discriminant_Specification,
20565 N_Formal_Object_Declaration,
20566 N_Object_Declaration,
20567 N_Object_Renaming_Declaration,
20568 N_Parameter_Specification,
20569 N_Subtype_Declaration);
20571 -- Create an Itype that is a duplicate of Entity (S) but with the
20572 -- null-exclusion attribute.
20574 if May_Have_Null_Exclusion
20575 and then Is_Access_Type (Entity (S))
20576 and then Null_Exclusion_Present (P)
20578 -- No need to check the case of an access to object definition.
20579 -- It is correct to define double not-null pointers.
20582 -- type Not_Null_Int_Ptr is not null access Integer;
20583 -- type Acc is not null access Not_Null_Int_Ptr;
20585 and then Nkind (P) /= N_Access_To_Object_Definition
20587 if Can_Never_Be_Null (Entity (S)) then
20588 case Nkind (Related_Nod) is
20589 when N_Full_Type_Declaration =>
20590 if Nkind (Type_Definition (Related_Nod))
20591 in N_Array_Type_Definition
20595 (Component_Definition
20596 (Type_Definition (Related_Nod)));
20599 Subtype_Indication (Type_Definition (Related_Nod));
20602 when N_Subtype_Declaration =>
20603 Error_Node := Subtype_Indication (Related_Nod);
20605 when N_Object_Declaration =>
20606 Error_Node := Object_Definition (Related_Nod);
20608 when N_Component_Declaration =>
20610 Subtype_Indication (Component_Definition (Related_Nod));
20612 when N_Allocator =>
20613 Error_Node := Expression (Related_Nod);
20616 pragma Assert (False);
20617 Error_Node := Related_Nod;
20621 ("`NOT NULL` not allowed (& already excludes null)",
20627 Create_Null_Excluding_Itype
20629 Related_Nod => P));
20630 Set_Entity (S, Etype (S));
20635 -- Case of constraint present, so that we have an N_Subtype_Indication
20636 -- node (this node is created only if constraints are present).
20639 Find_Type (Subtype_Mark (S));
20641 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
20643 (Nkind (Parent (S)) = N_Subtype_Declaration
20644 and then Is_Itype (Defining_Identifier (Parent (S))))
20646 Check_Incomplete (Subtype_Mark (S));
20650 Subtype_Mark_Id := Entity (Subtype_Mark (S));
20652 -- Explicit subtype declaration case
20654 if Nkind (P) = N_Subtype_Declaration then
20655 Def_Id := Defining_Identifier (P);
20657 -- Explicit derived type definition case
20659 elsif Nkind (P) = N_Derived_Type_Definition then
20660 Def_Id := Defining_Identifier (Parent (P));
20662 -- Implicit case, the Def_Id must be created as an implicit type.
20663 -- The one exception arises in the case of concurrent types, array
20664 -- and access types, where other subsidiary implicit types may be
20665 -- created and must appear before the main implicit type. In these
20666 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
20667 -- has not yet been called to create Def_Id.
20670 if Is_Array_Type (Subtype_Mark_Id)
20671 or else Is_Concurrent_Type (Subtype_Mark_Id)
20672 or else Is_Access_Type (Subtype_Mark_Id)
20676 -- For the other cases, we create a new unattached Itype,
20677 -- and set the indication to ensure it gets attached later.
20681 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
20685 -- If the kind of constraint is invalid for this kind of type,
20686 -- then give an error, and then pretend no constraint was given.
20688 if not Is_Valid_Constraint_Kind
20689 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
20692 ("incorrect constraint for this kind of type", Constraint (S));
20694 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
20696 -- Set Ekind of orphan itype, to prevent cascaded errors
20698 if Present (Def_Id) then
20699 Set_Ekind (Def_Id, Ekind (Any_Type));
20702 -- Make recursive call, having got rid of the bogus constraint
20704 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
20707 -- Remaining processing depends on type. Select on Base_Type kind to
20708 -- ensure getting to the concrete type kind in the case of a private
20709 -- subtype (needed when only doing semantic analysis).
20711 case Ekind (Base_Type (Subtype_Mark_Id)) is
20712 when Access_Kind =>
20714 -- If this is a constraint on a class-wide type, discard it.
20715 -- There is currently no way to express a partial discriminant
20716 -- constraint on a type with unknown discriminants. This is
20717 -- a pathology that the ACATS wisely decides not to test.
20719 if Is_Class_Wide_Type (Designated_Type (Subtype_Mark_Id)) then
20720 if Comes_From_Source (S) then
20722 ("constraint on class-wide type ignored??",
20726 if Nkind (P) = N_Subtype_Declaration then
20727 Set_Subtype_Indication (P,
20728 New_Occurrence_Of (Subtype_Mark_Id, Sloc (S)));
20731 return Subtype_Mark_Id;
20734 Constrain_Access (Def_Id, S, Related_Nod);
20737 and then Is_Itype (Designated_Type (Def_Id))
20738 and then Nkind (Related_Nod) = N_Subtype_Declaration
20739 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
20741 Build_Itype_Reference
20742 (Designated_Type (Def_Id), Related_Nod);
20746 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
20748 when Decimal_Fixed_Point_Kind =>
20749 Constrain_Decimal (Def_Id, S);
20751 when Enumeration_Kind =>
20752 Constrain_Enumeration (Def_Id, S);
20753 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
20755 when Ordinary_Fixed_Point_Kind =>
20756 Constrain_Ordinary_Fixed (Def_Id, S);
20759 Constrain_Float (Def_Id, S);
20761 when Integer_Kind =>
20762 Constrain_Integer (Def_Id, S);
20763 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
20765 when E_Record_Type |
20768 E_Incomplete_Type =>
20769 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
20771 if Ekind (Def_Id) = E_Incomplete_Type then
20772 Set_Private_Dependents (Def_Id, New_Elmt_List);
20775 when Private_Kind =>
20776 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
20777 Set_Private_Dependents (Def_Id, New_Elmt_List);
20779 -- In case of an invalid constraint prevent further processing
20780 -- since the type constructed is missing expected fields.
20782 if Etype (Def_Id) = Any_Type then
20786 -- If the full view is that of a task with discriminants,
20787 -- we must constrain both the concurrent type and its
20788 -- corresponding record type. Otherwise we will just propagate
20789 -- the constraint to the full view, if available.
20791 if Present (Full_View (Subtype_Mark_Id))
20792 and then Has_Discriminants (Subtype_Mark_Id)
20793 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
20796 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
20798 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
20799 Constrain_Concurrent (Full_View_Id, S,
20800 Related_Nod, Related_Id, Suffix);
20801 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
20802 Set_Full_View (Def_Id, Full_View_Id);
20804 -- Introduce an explicit reference to the private subtype,
20805 -- to prevent scope anomalies in gigi if first use appears
20806 -- in a nested context, e.g. a later function body.
20807 -- Should this be generated in other contexts than a full
20808 -- type declaration?
20810 if Is_Itype (Def_Id)
20812 Nkind (Parent (P)) = N_Full_Type_Declaration
20814 Build_Itype_Reference (Def_Id, Parent (P));
20818 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
20821 when Concurrent_Kind =>
20822 Constrain_Concurrent (Def_Id, S,
20823 Related_Nod, Related_Id, Suffix);
20826 Error_Msg_N ("invalid subtype mark in subtype indication", S);
20829 -- Size and Convention are always inherited from the base type
20831 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
20832 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
20836 end Process_Subtype;
20838 --------------------------------------------
20839 -- Propagate_Default_Init_Cond_Attributes --
20840 --------------------------------------------
20842 procedure Propagate_Default_Init_Cond_Attributes
20843 (From_Typ : Entity_Id;
20844 To_Typ : Entity_Id;
20845 Parent_To_Derivation : Boolean := False;
20846 Private_To_Full_View : Boolean := False)
20848 procedure Remove_Default_Init_Cond_Procedure (Typ : Entity_Id);
20849 -- Remove the default initial procedure (if any) from the rep chain of
20852 ----------------------------------------
20853 -- Remove_Default_Init_Cond_Procedure --
20854 ----------------------------------------
20856 procedure Remove_Default_Init_Cond_Procedure (Typ : Entity_Id) is
20857 Found : Boolean := False;
20863 Subp := Subprograms_For_Type (Typ);
20864 while Present (Subp) loop
20865 if Is_Default_Init_Cond_Procedure (Subp) then
20871 Subp := Subprograms_For_Type (Subp);
20875 Set_Subprograms_For_Type (Prev, Subprograms_For_Type (Subp));
20876 Set_Subprograms_For_Type (Subp, Empty);
20878 end Remove_Default_Init_Cond_Procedure;
20882 Inherit_Procedure : Boolean := False;
20884 -- Start of processing for Propagate_Default_Init_Cond_Attributes
20887 if Has_Default_Init_Cond (From_Typ) then
20889 -- A derived type inherits the attributes from its parent type
20891 if Parent_To_Derivation then
20892 Set_Has_Inherited_Default_Init_Cond (To_Typ);
20894 -- A full view shares the attributes with its private view
20897 Set_Has_Default_Init_Cond (To_Typ);
20900 Inherit_Procedure := True;
20902 -- Due to the order of expansion, a derived private type is processed
20903 -- by two routines which both attempt to set the attributes related
20904 -- to pragma Default_Initial_Condition - Build_Derived_Type and then
20905 -- Process_Full_View.
20908 -- type Parent_Typ is private
20909 -- with Default_Initial_Condition ...;
20911 -- type Parent_Typ is ...;
20914 -- with Pack; use Pack;
20915 -- package Pack_2 is
20916 -- type Deriv_Typ is private
20917 -- with Default_Initial_Condition ...;
20919 -- type Deriv_Typ is new Parent_Typ;
20922 -- When Build_Derived_Type operates, it sets the attributes on the
20923 -- full view without taking into account that the private view may
20924 -- define its own default initial condition procedure. This becomes
20925 -- apparent in Process_Full_View which must undo some of the work by
20926 -- Build_Derived_Type and propagate the attributes from the private
20927 -- to the full view.
20929 if Private_To_Full_View then
20930 Set_Has_Inherited_Default_Init_Cond (To_Typ, False);
20931 Remove_Default_Init_Cond_Procedure (To_Typ);
20934 -- A type must inherit the default initial condition procedure from a
20935 -- parent type when the parent itself is inheriting the procedure or
20936 -- when it is defining one. This circuitry is also used when dealing
20937 -- with the private / full view of a type.
20939 elsif Has_Inherited_Default_Init_Cond (From_Typ)
20940 or (Parent_To_Derivation
20941 and Present (Get_Pragma
20942 (From_Typ, Pragma_Default_Initial_Condition)))
20944 Set_Has_Inherited_Default_Init_Cond (To_Typ);
20945 Inherit_Procedure := True;
20948 if Inherit_Procedure
20949 and then No (Default_Init_Cond_Procedure (To_Typ))
20951 Set_Default_Init_Cond_Procedure
20952 (To_Typ, Default_Init_Cond_Procedure (From_Typ));
20954 end Propagate_Default_Init_Cond_Attributes;
20956 -----------------------------
20957 -- Record_Type_Declaration --
20958 -----------------------------
20960 procedure Record_Type_Declaration
20965 Def : constant Node_Id := Type_Definition (N);
20966 Is_Tagged : Boolean;
20967 Tag_Comp : Entity_Id;
20970 -- These flags must be initialized before calling Process_Discriminants
20971 -- because this routine makes use of them.
20973 Set_Ekind (T, E_Record_Type);
20975 Init_Size_Align (T);
20976 Set_Interfaces (T, No_Elist);
20977 Set_Stored_Constraint (T, No_Elist);
20978 Set_Default_SSO (T);
20982 if Ada_Version < Ada_2005 or else not Interface_Present (Def) then
20983 if Limited_Present (Def) then
20984 Check_SPARK_05_Restriction ("limited is not allowed", N);
20987 if Abstract_Present (Def) then
20988 Check_SPARK_05_Restriction ("abstract is not allowed", N);
20991 -- The flag Is_Tagged_Type might have already been set by
20992 -- Find_Type_Name if it detected an error for declaration T. This
20993 -- arises in the case of private tagged types where the full view
20994 -- omits the word tagged.
20997 Tagged_Present (Def)
20998 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
21000 Set_Is_Limited_Record (T, Limited_Present (Def));
21003 Set_Is_Tagged_Type (T, True);
21004 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
21007 -- Type is abstract if full declaration carries keyword, or if
21008 -- previous partial view did.
21010 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
21011 or else Abstract_Present (Def));
21014 Check_SPARK_05_Restriction ("interface is not allowed", N);
21017 Analyze_Interface_Declaration (T, Def);
21019 if Present (Discriminant_Specifications (N)) then
21021 ("interface types cannot have discriminants",
21022 Defining_Identifier
21023 (First (Discriminant_Specifications (N))));
21027 -- First pass: if there are self-referential access components,
21028 -- create the required anonymous access type declarations, and if
21029 -- need be an incomplete type declaration for T itself.
21031 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
21033 if Ada_Version >= Ada_2005
21034 and then Present (Interface_List (Def))
21036 Check_Interfaces (N, Def);
21039 Ifaces_List : Elist_Id;
21042 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
21043 -- already in the parents.
21047 Ifaces_List => Ifaces_List,
21048 Exclude_Parents => True);
21050 Set_Interfaces (T, Ifaces_List);
21054 -- Records constitute a scope for the component declarations within.
21055 -- The scope is created prior to the processing of these declarations.
21056 -- Discriminants are processed first, so that they are visible when
21057 -- processing the other components. The Ekind of the record type itself
21058 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
21060 -- Enter record scope
21064 -- If an incomplete or private type declaration was already given for
21065 -- the type, then this scope already exists, and the discriminants have
21066 -- been declared within. We must verify that the full declaration
21067 -- matches the incomplete one.
21069 Check_Or_Process_Discriminants (N, T, Prev);
21071 Set_Is_Constrained (T, not Has_Discriminants (T));
21072 Set_Has_Delayed_Freeze (T, True);
21074 -- For tagged types add a manually analyzed component corresponding
21075 -- to the component _tag, the corresponding piece of tree will be
21076 -- expanded as part of the freezing actions if it is not a CPP_Class.
21080 -- Do not add the tag unless we are in expansion mode
21082 if Expander_Active then
21083 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
21084 Enter_Name (Tag_Comp);
21086 Set_Ekind (Tag_Comp, E_Component);
21087 Set_Is_Tag (Tag_Comp);
21088 Set_Is_Aliased (Tag_Comp);
21089 Set_Etype (Tag_Comp, RTE (RE_Tag));
21090 Set_DT_Entry_Count (Tag_Comp, No_Uint);
21091 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
21092 Init_Component_Location (Tag_Comp);
21094 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
21095 -- implemented interfaces.
21097 if Has_Interfaces (T) then
21098 Add_Interface_Tag_Components (N, T);
21102 Make_Class_Wide_Type (T);
21103 Set_Direct_Primitive_Operations (T, New_Elmt_List);
21106 -- We must suppress range checks when processing record components in
21107 -- the presence of discriminants, since we don't want spurious checks to
21108 -- be generated during their analysis, but Suppress_Range_Checks flags
21109 -- must be reset the after processing the record definition.
21111 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
21112 -- couldn't we just use the normal range check suppression method here.
21113 -- That would seem cleaner ???
21115 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
21116 Set_Kill_Range_Checks (T, True);
21117 Record_Type_Definition (Def, Prev);
21118 Set_Kill_Range_Checks (T, False);
21120 Record_Type_Definition (Def, Prev);
21123 -- Exit from record scope
21127 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
21128 -- the implemented interfaces and associate them an aliased entity.
21131 and then not Is_Empty_List (Interface_List (Def))
21133 Derive_Progenitor_Subprograms (T, T);
21136 Check_Function_Writable_Actuals (N);
21137 end Record_Type_Declaration;
21139 ----------------------------
21140 -- Record_Type_Definition --
21141 ----------------------------
21143 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
21144 Component : Entity_Id;
21145 Ctrl_Components : Boolean := False;
21146 Final_Storage_Only : Boolean;
21150 if Ekind (Prev_T) = E_Incomplete_Type then
21151 T := Full_View (Prev_T);
21156 -- In SPARK, tagged types and type extensions may only be declared in
21157 -- the specification of library unit packages.
21159 if Present (Def) and then Is_Tagged_Type (T) then
21165 if Nkind (Parent (Def)) = N_Full_Type_Declaration then
21166 Typ := Parent (Def);
21169 (Nkind (Parent (Def)) = N_Derived_Type_Definition);
21170 Typ := Parent (Parent (Def));
21173 Ctxt := Parent (Typ);
21175 if Nkind (Ctxt) = N_Package_Body
21176 and then Nkind (Parent (Ctxt)) = N_Compilation_Unit
21178 Check_SPARK_05_Restriction
21179 ("type should be defined in package specification", Typ);
21181 elsif Nkind (Ctxt) /= N_Package_Specification
21182 or else Nkind (Parent (Parent (Ctxt))) /= N_Compilation_Unit
21184 Check_SPARK_05_Restriction
21185 ("type should be defined in library unit package", Typ);
21190 Final_Storage_Only := not Is_Controlled_Active (T);
21192 -- Ada 2005: Check whether an explicit Limited is present in a derived
21193 -- type declaration.
21195 if Nkind (Parent (Def)) = N_Derived_Type_Definition
21196 and then Limited_Present (Parent (Def))
21198 Set_Is_Limited_Record (T);
21201 -- If the component list of a record type is defined by the reserved
21202 -- word null and there is no discriminant part, then the record type has
21203 -- no components and all records of the type are null records (RM 3.7)
21204 -- This procedure is also called to process the extension part of a
21205 -- record extension, in which case the current scope may have inherited
21209 or else No (Component_List (Def))
21210 or else Null_Present (Component_List (Def))
21212 if not Is_Tagged_Type (T) then
21213 Check_SPARK_05_Restriction ("untagged record cannot be null", Def);
21217 Analyze_Declarations (Component_Items (Component_List (Def)));
21219 if Present (Variant_Part (Component_List (Def))) then
21220 Check_SPARK_05_Restriction ("variant part is not allowed", Def);
21221 Analyze (Variant_Part (Component_List (Def)));
21225 -- After completing the semantic analysis of the record definition,
21226 -- record components, both new and inherited, are accessible. Set their
21227 -- kind accordingly. Exclude malformed itypes from illegal declarations,
21228 -- whose Ekind may be void.
21230 Component := First_Entity (Current_Scope);
21231 while Present (Component) loop
21232 if Ekind (Component) = E_Void
21233 and then not Is_Itype (Component)
21235 Set_Ekind (Component, E_Component);
21236 Init_Component_Location (Component);
21239 if Has_Task (Etype (Component)) then
21243 if Has_Protected (Etype (Component)) then
21244 Set_Has_Protected (T);
21247 if Ekind (Component) /= E_Component then
21250 -- Do not set Has_Controlled_Component on a class-wide equivalent
21251 -- type. See Make_CW_Equivalent_Type.
21253 elsif not Is_Class_Wide_Equivalent_Type (T)
21254 and then (Has_Controlled_Component (Etype (Component))
21255 or else (Chars (Component) /= Name_uParent
21256 and then Is_Controlled_Active
21257 (Etype (Component))))
21259 Set_Has_Controlled_Component (T, True);
21260 Final_Storage_Only :=
21262 and then Finalize_Storage_Only (Etype (Component));
21263 Ctrl_Components := True;
21266 Next_Entity (Component);
21269 -- A Type is Finalize_Storage_Only only if all its controlled components
21272 if Ctrl_Components then
21273 Set_Finalize_Storage_Only (T, Final_Storage_Only);
21276 -- Place reference to end record on the proper entity, which may
21277 -- be a partial view.
21279 if Present (Def) then
21280 Process_End_Label (Def, 'e', Prev_T);
21282 end Record_Type_Definition;
21284 ------------------------
21285 -- Replace_Components --
21286 ------------------------
21288 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
21289 function Process (N : Node_Id) return Traverse_Result;
21295 function Process (N : Node_Id) return Traverse_Result is
21299 if Nkind (N) = N_Discriminant_Specification then
21300 Comp := First_Discriminant (Typ);
21301 while Present (Comp) loop
21302 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21303 Set_Defining_Identifier (N, Comp);
21307 Next_Discriminant (Comp);
21310 elsif Nkind (N) = N_Component_Declaration then
21311 Comp := First_Component (Typ);
21312 while Present (Comp) loop
21313 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21314 Set_Defining_Identifier (N, Comp);
21318 Next_Component (Comp);
21325 procedure Replace is new Traverse_Proc (Process);
21327 -- Start of processing for Replace_Components
21331 end Replace_Components;
21333 -------------------------------
21334 -- Set_Completion_Referenced --
21335 -------------------------------
21337 procedure Set_Completion_Referenced (E : Entity_Id) is
21339 -- If in main unit, mark entity that is a completion as referenced,
21340 -- warnings go on the partial view when needed.
21342 if In_Extended_Main_Source_Unit (E) then
21343 Set_Referenced (E);
21345 end Set_Completion_Referenced;
21347 ---------------------
21348 -- Set_Default_SSO --
21349 ---------------------
21351 procedure Set_Default_SSO (T : Entity_Id) is
21353 case Opt.Default_SSO is
21357 Set_SSO_Set_Low_By_Default (T, True);
21359 Set_SSO_Set_High_By_Default (T, True);
21361 raise Program_Error;
21363 end Set_Default_SSO;
21365 ---------------------
21366 -- Set_Fixed_Range --
21367 ---------------------
21369 -- The range for fixed-point types is complicated by the fact that we
21370 -- do not know the exact end points at the time of the declaration. This
21371 -- is true for three reasons:
21373 -- A size clause may affect the fudging of the end-points.
21374 -- A small clause may affect the values of the end-points.
21375 -- We try to include the end-points if it does not affect the size.
21377 -- This means that the actual end-points must be established at the
21378 -- point when the type is frozen. Meanwhile, we first narrow the range
21379 -- as permitted (so that it will fit if necessary in a small specified
21380 -- size), and then build a range subtree with these narrowed bounds.
21381 -- Set_Fixed_Range constructs the range from real literal values, and
21382 -- sets the range as the Scalar_Range of the given fixed-point type entity.
21384 -- The parent of this range is set to point to the entity so that it is
21385 -- properly hooked into the tree (unlike normal Scalar_Range entries for
21386 -- other scalar types, which are just pointers to the range in the
21387 -- original tree, this would otherwise be an orphan).
21389 -- The tree is left unanalyzed. When the type is frozen, the processing
21390 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
21391 -- analyzed, and uses this as an indication that it should complete
21392 -- work on the range (it will know the final small and size values).
21394 procedure Set_Fixed_Range
21400 S : constant Node_Id :=
21402 Low_Bound => Make_Real_Literal (Loc, Lo),
21403 High_Bound => Make_Real_Literal (Loc, Hi));
21405 Set_Scalar_Range (E, S);
21408 -- Before the freeze point, the bounds of a fixed point are universal
21409 -- and carry the corresponding type.
21411 Set_Etype (Low_Bound (S), Universal_Real);
21412 Set_Etype (High_Bound (S), Universal_Real);
21413 end Set_Fixed_Range;
21415 ----------------------------------
21416 -- Set_Scalar_Range_For_Subtype --
21417 ----------------------------------
21419 procedure Set_Scalar_Range_For_Subtype
21420 (Def_Id : Entity_Id;
21424 Kind : constant Entity_Kind := Ekind (Def_Id);
21427 -- Defend against previous error
21429 if Nkind (R) = N_Error then
21433 Set_Scalar_Range (Def_Id, R);
21435 -- We need to link the range into the tree before resolving it so
21436 -- that types that are referenced, including importantly the subtype
21437 -- itself, are properly frozen (Freeze_Expression requires that the
21438 -- expression be properly linked into the tree). Of course if it is
21439 -- already linked in, then we do not disturb the current link.
21441 if No (Parent (R)) then
21442 Set_Parent (R, Def_Id);
21445 -- Reset the kind of the subtype during analysis of the range, to
21446 -- catch possible premature use in the bounds themselves.
21448 Set_Ekind (Def_Id, E_Void);
21449 Process_Range_Expr_In_Decl (R, Subt, Subtyp => Def_Id);
21450 Set_Ekind (Def_Id, Kind);
21451 end Set_Scalar_Range_For_Subtype;
21453 --------------------------------------------------------
21454 -- Set_Stored_Constraint_From_Discriminant_Constraint --
21455 --------------------------------------------------------
21457 procedure Set_Stored_Constraint_From_Discriminant_Constraint
21461 -- Make sure set if encountered during Expand_To_Stored_Constraint
21463 Set_Stored_Constraint (E, No_Elist);
21465 -- Give it the right value
21467 if Is_Constrained (E) and then Has_Discriminants (E) then
21468 Set_Stored_Constraint (E,
21469 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
21471 end Set_Stored_Constraint_From_Discriminant_Constraint;
21473 -------------------------------------
21474 -- Signed_Integer_Type_Declaration --
21475 -------------------------------------
21477 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
21478 Implicit_Base : Entity_Id;
21479 Base_Typ : Entity_Id;
21482 Errs : Boolean := False;
21486 function Can_Derive_From (E : Entity_Id) return Boolean;
21487 -- Determine whether given bounds allow derivation from specified type
21489 procedure Check_Bound (Expr : Node_Id);
21490 -- Check bound to make sure it is integral and static. If not, post
21491 -- appropriate error message and set Errs flag
21493 ---------------------
21494 -- Can_Derive_From --
21495 ---------------------
21497 -- Note we check both bounds against both end values, to deal with
21498 -- strange types like ones with a range of 0 .. -12341234.
21500 function Can_Derive_From (E : Entity_Id) return Boolean is
21501 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
21502 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
21504 return Lo <= Lo_Val and then Lo_Val <= Hi
21506 Lo <= Hi_Val and then Hi_Val <= Hi;
21507 end Can_Derive_From;
21513 procedure Check_Bound (Expr : Node_Id) is
21515 -- If a range constraint is used as an integer type definition, each
21516 -- bound of the range must be defined by a static expression of some
21517 -- integer type, but the two bounds need not have the same integer
21518 -- type (Negative bounds are allowed.) (RM 3.5.4)
21520 if not Is_Integer_Type (Etype (Expr)) then
21522 ("integer type definition bounds must be of integer type", Expr);
21525 elsif not Is_OK_Static_Expression (Expr) then
21526 Flag_Non_Static_Expr
21527 ("non-static expression used for integer type bound!", Expr);
21530 -- The bounds are folded into literals, and we set their type to be
21531 -- universal, to avoid typing difficulties: we cannot set the type
21532 -- of the literal to the new type, because this would be a forward
21533 -- reference for the back end, and if the original type is user-
21534 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
21537 if Is_Entity_Name (Expr) then
21538 Fold_Uint (Expr, Expr_Value (Expr), True);
21541 Set_Etype (Expr, Universal_Integer);
21545 -- Start of processing for Signed_Integer_Type_Declaration
21548 -- Create an anonymous base type
21551 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
21553 -- Analyze and check the bounds, they can be of any integer type
21555 Lo := Low_Bound (Def);
21556 Hi := High_Bound (Def);
21558 -- Arbitrarily use Integer as the type if either bound had an error
21560 if Hi = Error or else Lo = Error then
21561 Base_Typ := Any_Integer;
21562 Set_Error_Posted (T, True);
21564 -- Here both bounds are OK expressions
21567 Analyze_And_Resolve (Lo, Any_Integer);
21568 Analyze_And_Resolve (Hi, Any_Integer);
21574 Hi := Type_High_Bound (Standard_Long_Long_Integer);
21575 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
21578 -- Find type to derive from
21580 Lo_Val := Expr_Value (Lo);
21581 Hi_Val := Expr_Value (Hi);
21583 if Can_Derive_From (Standard_Short_Short_Integer) then
21584 Base_Typ := Base_Type (Standard_Short_Short_Integer);
21586 elsif Can_Derive_From (Standard_Short_Integer) then
21587 Base_Typ := Base_Type (Standard_Short_Integer);
21589 elsif Can_Derive_From (Standard_Integer) then
21590 Base_Typ := Base_Type (Standard_Integer);
21592 elsif Can_Derive_From (Standard_Long_Integer) then
21593 Base_Typ := Base_Type (Standard_Long_Integer);
21595 elsif Can_Derive_From (Standard_Long_Long_Integer) then
21596 Check_Restriction (No_Long_Long_Integers, Def);
21597 Base_Typ := Base_Type (Standard_Long_Long_Integer);
21600 Base_Typ := Base_Type (Standard_Long_Long_Integer);
21601 Error_Msg_N ("integer type definition bounds out of range", Def);
21602 Hi := Type_High_Bound (Standard_Long_Long_Integer);
21603 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
21607 -- Complete both implicit base and declared first subtype entities. The
21608 -- inheritance of the rep item chain ensures that SPARK-related pragmas
21609 -- are not clobbered when the signed integer type acts as a full view of
21612 Set_Etype (Implicit_Base, Base_Typ);
21613 Set_Size_Info (Implicit_Base, Base_Typ);
21614 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
21615 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
21616 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
21618 Set_Ekind (T, E_Signed_Integer_Subtype);
21619 Set_Etype (T, Implicit_Base);
21620 Set_Size_Info (T, Implicit_Base);
21621 Inherit_Rep_Item_Chain (T, Implicit_Base);
21622 Set_Scalar_Range (T, Def);
21623 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
21624 Set_Is_Constrained (T);
21625 end Signed_Integer_Type_Declaration;