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));
4836 Copy_Dimensions (From => T, To => Id);
4838 when Signed_Integer_Kind =>
4839 Set_Ekind (Id, E_Signed_Integer_Subtype);
4840 Set_Scalar_Range (Id, Scalar_Range (T));
4841 Set_Is_Constrained (Id, Is_Constrained (T));
4842 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4843 Set_RM_Size (Id, RM_Size (T));
4844 Inherit_Predicate_Flags (Id, T);
4846 when Modular_Integer_Kind =>
4847 Set_Ekind (Id, E_Modular_Integer_Subtype);
4848 Set_Scalar_Range (Id, Scalar_Range (T));
4849 Set_Is_Constrained (Id, Is_Constrained (T));
4850 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4851 Set_RM_Size (Id, RM_Size (T));
4852 Inherit_Predicate_Flags (Id, T);
4854 when Class_Wide_Kind =>
4855 Set_Ekind (Id, E_Class_Wide_Subtype);
4856 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4857 Set_Cloned_Subtype (Id, T);
4858 Set_Is_Tagged_Type (Id, True);
4859 Set_Has_Unknown_Discriminants
4861 Set_No_Tagged_Streams_Pragma
4862 (Id, No_Tagged_Streams_Pragma (T));
4864 if Ekind (T) = E_Class_Wide_Subtype then
4865 Set_Equivalent_Type (Id, Equivalent_Type (T));
4868 when E_Record_Type | E_Record_Subtype =>
4869 Set_Ekind (Id, E_Record_Subtype);
4871 if Ekind (T) = E_Record_Subtype
4872 and then Present (Cloned_Subtype (T))
4874 Set_Cloned_Subtype (Id, Cloned_Subtype (T));
4876 Set_Cloned_Subtype (Id, T);
4879 Set_First_Entity (Id, First_Entity (T));
4880 Set_Last_Entity (Id, Last_Entity (T));
4881 Set_Has_Discriminants (Id, Has_Discriminants (T));
4882 Set_Is_Constrained (Id, Is_Constrained (T));
4883 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4884 Set_Has_Implicit_Dereference
4885 (Id, Has_Implicit_Dereference (T));
4886 Set_Has_Unknown_Discriminants
4887 (Id, Has_Unknown_Discriminants (T));
4889 if Has_Discriminants (T) then
4890 Set_Discriminant_Constraint
4891 (Id, Discriminant_Constraint (T));
4892 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4894 elsif Has_Unknown_Discriminants (Id) then
4895 Set_Discriminant_Constraint (Id, No_Elist);
4898 if Is_Tagged_Type (T) then
4899 Set_Is_Tagged_Type (Id, True);
4900 Set_No_Tagged_Streams_Pragma
4901 (Id, No_Tagged_Streams_Pragma (T));
4902 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4903 Set_Direct_Primitive_Operations
4904 (Id, Direct_Primitive_Operations (T));
4905 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4907 if Is_Interface (T) then
4908 Set_Is_Interface (Id);
4909 Set_Is_Limited_Interface (Id, Is_Limited_Interface (T));
4913 when Private_Kind =>
4914 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4915 Set_Has_Discriminants (Id, Has_Discriminants (T));
4916 Set_Is_Constrained (Id, Is_Constrained (T));
4917 Set_First_Entity (Id, First_Entity (T));
4918 Set_Last_Entity (Id, Last_Entity (T));
4919 Set_Private_Dependents (Id, New_Elmt_List);
4920 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4921 Set_Has_Implicit_Dereference
4922 (Id, Has_Implicit_Dereference (T));
4923 Set_Has_Unknown_Discriminants
4924 (Id, Has_Unknown_Discriminants (T));
4925 Set_Known_To_Have_Preelab_Init
4926 (Id, Known_To_Have_Preelab_Init (T));
4928 if Is_Tagged_Type (T) then
4929 Set_Is_Tagged_Type (Id);
4930 Set_No_Tagged_Streams_Pragma (Id,
4931 No_Tagged_Streams_Pragma (T));
4932 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4933 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4934 Set_Direct_Primitive_Operations (Id,
4935 Direct_Primitive_Operations (T));
4938 -- In general the attributes of the subtype of a private type
4939 -- are the attributes of the partial view of parent. However,
4940 -- the full view may be a discriminated type, and the subtype
4941 -- must share the discriminant constraint to generate correct
4942 -- calls to initialization procedures.
4944 if Has_Discriminants (T) then
4945 Set_Discriminant_Constraint
4946 (Id, Discriminant_Constraint (T));
4947 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4949 elsif Present (Full_View (T))
4950 and then Has_Discriminants (Full_View (T))
4952 Set_Discriminant_Constraint
4953 (Id, Discriminant_Constraint (Full_View (T)));
4954 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4956 -- This would seem semantically correct, but apparently
4957 -- generates spurious errors about missing components ???
4959 -- Set_Has_Discriminants (Id);
4962 Prepare_Private_Subtype_Completion (Id, N);
4964 -- If this is the subtype of a constrained private type with
4965 -- discriminants that has got a full view and we also have
4966 -- built a completion just above, show that the completion
4967 -- is a clone of the full view to the back-end.
4969 if Has_Discriminants (T)
4970 and then not Has_Unknown_Discriminants (T)
4971 and then not Is_Empty_Elmt_List (Discriminant_Constraint (T))
4972 and then Present (Full_View (T))
4973 and then Present (Full_View (Id))
4975 Set_Cloned_Subtype (Full_View (Id), Full_View (T));
4979 Set_Ekind (Id, E_Access_Subtype);
4980 Set_Is_Constrained (Id, Is_Constrained (T));
4981 Set_Is_Access_Constant
4982 (Id, Is_Access_Constant (T));
4983 Set_Directly_Designated_Type
4984 (Id, Designated_Type (T));
4985 Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T));
4987 -- A Pure library_item must not contain the declaration of a
4988 -- named access type, except within a subprogram, generic
4989 -- subprogram, task unit, or protected unit, or if it has
4990 -- a specified Storage_Size of zero (RM05-10.2.1(15.4-15.5)).
4992 if Comes_From_Source (Id)
4993 and then In_Pure_Unit
4994 and then not In_Subprogram_Task_Protected_Unit
4995 and then not No_Pool_Assigned (Id)
4998 ("named access types not allowed in pure unit", N);
5001 when Concurrent_Kind =>
5002 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
5003 Set_Corresponding_Record_Type (Id,
5004 Corresponding_Record_Type (T));
5005 Set_First_Entity (Id, First_Entity (T));
5006 Set_First_Private_Entity (Id, First_Private_Entity (T));
5007 Set_Has_Discriminants (Id, Has_Discriminants (T));
5008 Set_Is_Constrained (Id, Is_Constrained (T));
5009 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
5010 Set_Last_Entity (Id, Last_Entity (T));
5012 if Is_Tagged_Type (T) then
5013 Set_No_Tagged_Streams_Pragma
5014 (Id, No_Tagged_Streams_Pragma (T));
5017 if Has_Discriminants (T) then
5018 Set_Discriminant_Constraint
5019 (Id, Discriminant_Constraint (T));
5020 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5023 when Incomplete_Kind =>
5024 if Ada_Version >= Ada_2005 then
5026 -- In Ada 2005 an incomplete type can be explicitly tagged:
5027 -- propagate indication. Note that we also have to include
5028 -- subtypes for Ada 2012 extended use of incomplete types.
5030 Set_Ekind (Id, E_Incomplete_Subtype);
5031 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
5032 Set_Private_Dependents (Id, New_Elmt_List);
5034 if Is_Tagged_Type (Id) then
5035 Set_No_Tagged_Streams_Pragma
5036 (Id, No_Tagged_Streams_Pragma (T));
5037 Set_Direct_Primitive_Operations (Id, New_Elmt_List);
5040 -- Ada 2005 (AI-412): Decorate an incomplete subtype of an
5041 -- incomplete type visible through a limited with clause.
5043 if From_Limited_With (T)
5044 and then Present (Non_Limited_View (T))
5046 Set_From_Limited_With (Id);
5047 Set_Non_Limited_View (Id, Non_Limited_View (T));
5049 -- Ada 2005 (AI-412): Add the regular incomplete subtype
5050 -- to the private dependents of the original incomplete
5051 -- type for future transformation.
5054 Append_Elmt (Id, Private_Dependents (T));
5057 -- If the subtype name denotes an incomplete type an error
5058 -- was already reported by Process_Subtype.
5061 Set_Etype (Id, Any_Type);
5065 raise Program_Error;
5069 if Etype (Id) = Any_Type then
5073 -- Some common processing on all types
5075 Set_Size_Info (Id, T);
5076 Set_First_Rep_Item (Id, First_Rep_Item (T));
5078 -- If the parent type is a generic actual, so is the subtype. This may
5079 -- happen in a nested instance. Why Comes_From_Source test???
5081 if not Comes_From_Source (N) then
5082 Set_Is_Generic_Actual_Type (Id, Is_Generic_Actual_Type (T));
5087 Set_Is_Immediately_Visible (Id, True);
5088 Set_Depends_On_Private (Id, Has_Private_Component (T));
5089 Set_Is_Descendent_Of_Address (Id, Is_Descendent_Of_Address (T));
5091 if Is_Interface (T) then
5092 Set_Is_Interface (Id);
5095 if Present (Generic_Parent_Type (N))
5097 (Nkind (Parent (Generic_Parent_Type (N))) /=
5098 N_Formal_Type_Declaration
5099 or else Nkind (Formal_Type_Definition
5100 (Parent (Generic_Parent_Type (N)))) /=
5101 N_Formal_Private_Type_Definition)
5103 if Is_Tagged_Type (Id) then
5105 -- If this is a generic actual subtype for a synchronized type,
5106 -- the primitive operations are those of the corresponding record
5107 -- for which there is a separate subtype declaration.
5109 if Is_Concurrent_Type (Id) then
5111 elsif Is_Class_Wide_Type (Id) then
5112 Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T));
5114 Derive_Subprograms (Generic_Parent_Type (N), Id, T);
5117 elsif Scope (Etype (Id)) /= Standard_Standard then
5118 Derive_Subprograms (Generic_Parent_Type (N), Id);
5122 if Is_Private_Type (T) and then Present (Full_View (T)) then
5123 Conditional_Delay (Id, Full_View (T));
5125 -- The subtypes of components or subcomponents of protected types
5126 -- do not need freeze nodes, which would otherwise appear in the
5127 -- wrong scope (before the freeze node for the protected type). The
5128 -- proper subtypes are those of the subcomponents of the corresponding
5131 elsif Ekind (Scope (Id)) /= E_Protected_Type
5132 and then Present (Scope (Scope (Id))) -- error defense
5133 and then Ekind (Scope (Scope (Id))) /= E_Protected_Type
5135 Conditional_Delay (Id, T);
5138 -- Check that Constraint_Error is raised for a scalar subtype indication
5139 -- when the lower or upper bound of a non-null range lies outside the
5140 -- range of the type mark.
5142 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5143 if Is_Scalar_Type (Etype (Id))
5144 and then Scalar_Range (Id) /=
5145 Scalar_Range (Etype (Subtype_Mark
5146 (Subtype_Indication (N))))
5150 Etype (Subtype_Mark (Subtype_Indication (N))));
5152 -- In the array case, check compatibility for each index
5154 elsif Is_Array_Type (Etype (Id)) and then Present (First_Index (Id))
5156 -- This really should be a subprogram that finds the indications
5160 Subt_Index : Node_Id := First_Index (Id);
5161 Target_Index : Node_Id :=
5163 (Subtype_Mark (Subtype_Indication (N))));
5164 Has_Dyn_Chk : Boolean := Has_Dynamic_Range_Check (N);
5167 while Present (Subt_Index) loop
5168 if ((Nkind (Subt_Index) = N_Identifier
5169 and then Ekind (Entity (Subt_Index)) in Scalar_Kind)
5170 or else Nkind (Subt_Index) = N_Subtype_Indication)
5172 Nkind (Scalar_Range (Etype (Subt_Index))) = N_Range
5175 Target_Typ : constant Entity_Id :=
5176 Etype (Target_Index);
5180 (Scalar_Range (Etype (Subt_Index)),
5183 Defining_Identifier (N));
5185 -- Reset Has_Dynamic_Range_Check on the subtype to
5186 -- prevent elision of the index check due to a dynamic
5187 -- check generated for a preceding index (needed since
5188 -- Insert_Range_Checks tries to avoid generating
5189 -- redundant checks on a given declaration).
5191 Set_Has_Dynamic_Range_Check (N, False);
5197 Sloc (Defining_Identifier (N)));
5199 -- Record whether this index involved a dynamic check
5202 Has_Dyn_Chk or else Has_Dynamic_Range_Check (N);
5206 Next_Index (Subt_Index);
5207 Next_Index (Target_Index);
5210 -- Finally, mark whether the subtype involves dynamic checks
5212 Set_Has_Dynamic_Range_Check (N, Has_Dyn_Chk);
5217 -- A type invariant applies to any subtype in its scope, in particular
5218 -- to a generic actual.
5220 if Has_Invariants (T) and then In_Open_Scopes (Scope (T)) then
5221 Set_Has_Invariants (Id);
5222 Set_Invariant_Procedure (Id, Invariant_Procedure (T));
5225 -- Make sure that generic actual types are properly frozen. The subtype
5226 -- is marked as a generic actual type when the enclosing instance is
5227 -- analyzed, so here we identify the subtype from the tree structure.
5230 and then Is_Generic_Actual_Type (Id)
5231 and then In_Instance
5232 and then not Comes_From_Source (N)
5233 and then Nkind (Subtype_Indication (N)) /= N_Subtype_Indication
5234 and then Is_Frozen (T)
5236 Freeze_Before (N, Id);
5239 Set_Optimize_Alignment_Flags (Id);
5240 Check_Eliminated (Id);
5243 if Has_Aspects (N) then
5244 Analyze_Aspect_Specifications (N, Id);
5247 Analyze_Dimension (N);
5249 -- Check No_Dynamic_Sized_Objects restriction, which disallows subtype
5250 -- indications on composite types where the constraints are dynamic.
5251 -- Note that object declarations and aggregates generate implicit
5252 -- subtype declarations, which this covers. One special case is that the
5253 -- implicitly generated "=" for discriminated types includes an
5254 -- offending subtype declaration, which is harmless, so we ignore it
5257 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5259 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
5261 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint
5262 and then not (Is_Internal (Id)
5263 and then Is_TSS (Scope (Id),
5264 TSS_Composite_Equality))
5265 and then not Within_Init_Proc
5266 and then not All_Composite_Constraints_Static (Cstr)
5268 Check_Restriction (No_Dynamic_Sized_Objects, Cstr);
5272 end Analyze_Subtype_Declaration;
5274 --------------------------------
5275 -- Analyze_Subtype_Indication --
5276 --------------------------------
5278 procedure Analyze_Subtype_Indication (N : Node_Id) is
5279 T : constant Entity_Id := Subtype_Mark (N);
5280 R : constant Node_Id := Range_Expression (Constraint (N));
5287 Set_Etype (N, Etype (R));
5288 Resolve (R, Entity (T));
5290 Set_Error_Posted (R);
5291 Set_Error_Posted (T);
5293 end Analyze_Subtype_Indication;
5295 --------------------------
5296 -- Analyze_Variant_Part --
5297 --------------------------
5299 procedure Analyze_Variant_Part (N : Node_Id) is
5300 Discr_Name : Node_Id;
5301 Discr_Type : Entity_Id;
5303 procedure Process_Variant (A : Node_Id);
5304 -- Analyze declarations for a single variant
5306 package Analyze_Variant_Choices is
5307 new Generic_Analyze_Choices (Process_Variant);
5308 use Analyze_Variant_Choices;
5310 ---------------------
5311 -- Process_Variant --
5312 ---------------------
5314 procedure Process_Variant (A : Node_Id) is
5315 CL : constant Node_Id := Component_List (A);
5317 if not Null_Present (CL) then
5318 Analyze_Declarations (Component_Items (CL));
5320 if Present (Variant_Part (CL)) then
5321 Analyze (Variant_Part (CL));
5324 end Process_Variant;
5326 -- Start of processing for Analyze_Variant_Part
5329 Discr_Name := Name (N);
5330 Analyze (Discr_Name);
5332 -- If Discr_Name bad, get out (prevent cascaded errors)
5334 if Etype (Discr_Name) = Any_Type then
5338 -- Check invalid discriminant in variant part
5340 if Ekind (Entity (Discr_Name)) /= E_Discriminant then
5341 Error_Msg_N ("invalid discriminant name in variant part", Discr_Name);
5344 Discr_Type := Etype (Entity (Discr_Name));
5346 if not Is_Discrete_Type (Discr_Type) then
5348 ("discriminant in a variant part must be of a discrete type",
5353 -- Now analyze the choices, which also analyzes the declarations that
5354 -- are associated with each choice.
5356 Analyze_Choices (Variants (N), Discr_Type);
5358 -- Note: we used to instantiate and call Check_Choices here to check
5359 -- that the choices covered the discriminant, but it's too early to do
5360 -- that because of statically predicated subtypes, whose analysis may
5361 -- be deferred to their freeze point which may be as late as the freeze
5362 -- point of the containing record. So this call is now to be found in
5363 -- Freeze_Record_Declaration.
5365 end Analyze_Variant_Part;
5367 ----------------------------
5368 -- Array_Type_Declaration --
5369 ----------------------------
5371 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is
5372 Component_Def : constant Node_Id := Component_Definition (Def);
5373 Component_Typ : constant Node_Id := Subtype_Indication (Component_Def);
5374 Element_Type : Entity_Id;
5375 Implicit_Base : Entity_Id;
5377 Related_Id : Entity_Id := Empty;
5379 P : constant Node_Id := Parent (Def);
5383 if Nkind (Def) = N_Constrained_Array_Definition then
5384 Index := First (Discrete_Subtype_Definitions (Def));
5386 Index := First (Subtype_Marks (Def));
5389 -- Find proper names for the implicit types which may be public. In case
5390 -- of anonymous arrays we use the name of the first object of that type
5394 Related_Id := Defining_Identifier (P);
5400 while Present (Index) loop
5403 -- Test for odd case of trying to index a type by the type itself
5405 if Is_Entity_Name (Index) and then Entity (Index) = T then
5406 Error_Msg_N ("type& cannot be indexed by itself", Index);
5407 Set_Entity (Index, Standard_Boolean);
5408 Set_Etype (Index, Standard_Boolean);
5411 -- Check SPARK restriction requiring a subtype mark
5413 if not Nkind_In (Index, N_Identifier, N_Expanded_Name) then
5414 Check_SPARK_05_Restriction ("subtype mark required", Index);
5417 -- Add a subtype declaration for each index of private array type
5418 -- declaration whose etype is also private. For example:
5421 -- type Index is private;
5423 -- type Table is array (Index) of ...
5426 -- This is currently required by the expander for the internally
5427 -- generated equality subprogram of records with variant parts in
5428 -- which the etype of some component is such private type.
5430 if Ekind (Current_Scope) = E_Package
5431 and then In_Private_Part (Current_Scope)
5432 and then Has_Private_Declaration (Etype (Index))
5435 Loc : constant Source_Ptr := Sloc (Def);
5440 New_E := Make_Temporary (Loc, 'T');
5441 Set_Is_Internal (New_E);
5444 Make_Subtype_Declaration (Loc,
5445 Defining_Identifier => New_E,
5446 Subtype_Indication =>
5447 New_Occurrence_Of (Etype (Index), Loc));
5449 Insert_Before (Parent (Def), Decl);
5451 Set_Etype (Index, New_E);
5453 -- If the index is a range the Entity attribute is not
5454 -- available. Example:
5457 -- type T is private;
5459 -- type T is new Natural;
5460 -- Table : array (T(1) .. T(10)) of Boolean;
5463 if Nkind (Index) /= N_Range then
5464 Set_Entity (Index, New_E);
5469 Make_Index (Index, P, Related_Id, Nb_Index);
5471 -- Check error of subtype with predicate for index type
5473 Bad_Predicated_Subtype_Use
5474 ("subtype& has predicate, not allowed as index subtype",
5475 Index, Etype (Index));
5477 -- Move to next index
5480 Nb_Index := Nb_Index + 1;
5483 -- Process subtype indication if one is present
5485 if Present (Component_Typ) then
5486 Element_Type := Process_Subtype (Component_Typ, P, Related_Id, 'C');
5488 Set_Etype (Component_Typ, Element_Type);
5490 if not Nkind_In (Component_Typ, N_Identifier, N_Expanded_Name) then
5491 Check_SPARK_05_Restriction
5492 ("subtype mark required", Component_Typ);
5495 -- Ada 2005 (AI-230): Access Definition case
5497 else pragma Assert (Present (Access_Definition (Component_Def)));
5499 -- Indicate that the anonymous access type is created by the
5500 -- array type declaration.
5502 Element_Type := Access_Definition
5504 N => Access_Definition (Component_Def));
5505 Set_Is_Local_Anonymous_Access (Element_Type);
5507 -- Propagate the parent. This field is needed if we have to generate
5508 -- the master_id associated with an anonymous access to task type
5509 -- component (see Expand_N_Full_Type_Declaration.Build_Master)
5511 Set_Parent (Element_Type, Parent (T));
5513 -- Ada 2005 (AI-230): In case of components that are anonymous access
5514 -- types the level of accessibility depends on the enclosing type
5517 Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230)
5519 -- Ada 2005 (AI-254)
5522 CD : constant Node_Id :=
5523 Access_To_Subprogram_Definition
5524 (Access_Definition (Component_Def));
5526 if Present (CD) and then Protected_Present (CD) then
5528 Replace_Anonymous_Access_To_Protected_Subprogram (Def);
5533 -- Constrained array case
5536 T := Create_Itype (E_Void, P, Related_Id, 'T');
5539 if Nkind (Def) = N_Constrained_Array_Definition then
5541 -- Establish Implicit_Base as unconstrained base type
5543 Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B');
5545 Set_Etype (Implicit_Base, Implicit_Base);
5546 Set_Scope (Implicit_Base, Current_Scope);
5547 Set_Has_Delayed_Freeze (Implicit_Base);
5548 Set_Default_SSO (Implicit_Base);
5550 -- The constrained array type is a subtype of the unconstrained one
5552 Set_Ekind (T, E_Array_Subtype);
5553 Init_Size_Align (T);
5554 Set_Etype (T, Implicit_Base);
5555 Set_Scope (T, Current_Scope);
5556 Set_Is_Constrained (T);
5558 First (Discrete_Subtype_Definitions (Def)));
5559 Set_Has_Delayed_Freeze (T);
5561 -- Complete setup of implicit base type
5563 Set_First_Index (Implicit_Base, First_Index (T));
5564 Set_Component_Type (Implicit_Base, Element_Type);
5565 Set_Has_Task (Implicit_Base, Has_Task (Element_Type));
5566 Set_Has_Protected (Implicit_Base, Has_Protected (Element_Type));
5567 Set_Component_Size (Implicit_Base, Uint_0);
5568 Set_Packed_Array_Impl_Type (Implicit_Base, Empty);
5569 Set_Has_Controlled_Component (Implicit_Base,
5570 Has_Controlled_Component (Element_Type)
5571 or else Is_Controlled_Active (Element_Type));
5572 Set_Finalize_Storage_Only (Implicit_Base,
5573 Finalize_Storage_Only (Element_Type));
5575 -- Inherit the "ghostness" from the constrained array type
5577 if Ghost_Mode > None or else Is_Ghost_Entity (T) then
5578 Set_Is_Ghost_Entity (Implicit_Base);
5581 -- Unconstrained array case
5584 Set_Ekind (T, E_Array_Type);
5585 Init_Size_Align (T);
5587 Set_Scope (T, Current_Scope);
5588 Set_Component_Size (T, Uint_0);
5589 Set_Is_Constrained (T, False);
5590 Set_First_Index (T, First (Subtype_Marks (Def)));
5591 Set_Has_Delayed_Freeze (T, True);
5592 Set_Has_Task (T, Has_Task (Element_Type));
5593 Set_Has_Protected (T, Has_Protected (Element_Type));
5594 Set_Has_Controlled_Component (T, Has_Controlled_Component
5597 Is_Controlled_Active (Element_Type));
5598 Set_Finalize_Storage_Only (T, Finalize_Storage_Only
5600 Set_Default_SSO (T);
5603 -- Common attributes for both cases
5605 Set_Component_Type (Base_Type (T), Element_Type);
5606 Set_Packed_Array_Impl_Type (T, Empty);
5608 if Aliased_Present (Component_Definition (Def)) then
5609 Check_SPARK_05_Restriction
5610 ("aliased is not allowed", Component_Definition (Def));
5611 Set_Has_Aliased_Components (Etype (T));
5614 -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the
5615 -- array type to ensure that objects of this type are initialized.
5617 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (Element_Type) then
5618 Set_Can_Never_Be_Null (T);
5620 if Null_Exclusion_Present (Component_Definition (Def))
5622 -- No need to check itypes because in their case this check was
5623 -- done at their point of creation
5625 and then not Is_Itype (Element_Type)
5628 ("`NOT NULL` not allowed (null already excluded)",
5629 Subtype_Indication (Component_Definition (Def)));
5633 Priv := Private_Component (Element_Type);
5635 if Present (Priv) then
5637 -- Check for circular definitions
5639 if Priv = Any_Type then
5640 Set_Component_Type (Etype (T), Any_Type);
5642 -- There is a gap in the visibility of operations on the composite
5643 -- type only if the component type is defined in a different scope.
5645 elsif Scope (Priv) = Current_Scope then
5648 elsif Is_Limited_Type (Priv) then
5649 Set_Is_Limited_Composite (Etype (T));
5650 Set_Is_Limited_Composite (T);
5652 Set_Is_Private_Composite (Etype (T));
5653 Set_Is_Private_Composite (T);
5657 -- A syntax error in the declaration itself may lead to an empty index
5658 -- list, in which case do a minimal patch.
5660 if No (First_Index (T)) then
5661 Error_Msg_N ("missing index definition in array type declaration", T);
5664 Indexes : constant List_Id :=
5665 New_List (New_Occurrence_Of (Any_Id, Sloc (T)));
5667 Set_Discrete_Subtype_Definitions (Def, Indexes);
5668 Set_First_Index (T, First (Indexes));
5673 -- Create a concatenation operator for the new type. Internal array
5674 -- types created for packed entities do not need such, they are
5675 -- compatible with the user-defined type.
5677 if Number_Dimensions (T) = 1
5678 and then not Is_Packed_Array_Impl_Type (T)
5680 New_Concatenation_Op (T);
5683 -- In the case of an unconstrained array the parser has already verified
5684 -- that all the indexes are unconstrained but we still need to make sure
5685 -- that the element type is constrained.
5687 if not Is_Definite_Subtype (Element_Type) then
5689 ("unconstrained element type in array declaration",
5690 Subtype_Indication (Component_Def));
5692 elsif Is_Abstract_Type (Element_Type) then
5694 ("the type of a component cannot be abstract",
5695 Subtype_Indication (Component_Def));
5698 -- There may be an invariant declared for the component type, but
5699 -- the construction of the component invariant checking procedure
5700 -- takes place during expansion.
5701 end Array_Type_Declaration;
5703 ------------------------------------------------------
5704 -- Replace_Anonymous_Access_To_Protected_Subprogram --
5705 ------------------------------------------------------
5707 function Replace_Anonymous_Access_To_Protected_Subprogram
5708 (N : Node_Id) return Entity_Id
5710 Loc : constant Source_Ptr := Sloc (N);
5712 Curr_Scope : constant Scope_Stack_Entry :=
5713 Scope_Stack.Table (Scope_Stack.Last);
5715 Anon : constant Entity_Id := Make_Temporary (Loc, 'S');
5718 -- Access definition in declaration
5721 -- Object definition or formal definition with an access definition
5724 -- Declaration of anonymous access to subprogram type
5727 -- Original specification in access to subprogram
5732 Set_Is_Internal (Anon);
5735 when N_Component_Declaration |
5736 N_Unconstrained_Array_Definition |
5737 N_Constrained_Array_Definition =>
5738 Comp := Component_Definition (N);
5739 Acc := Access_Definition (Comp);
5741 when N_Discriminant_Specification =>
5742 Comp := Discriminant_Type (N);
5745 when N_Parameter_Specification =>
5746 Comp := Parameter_Type (N);
5749 when N_Access_Function_Definition =>
5750 Comp := Result_Definition (N);
5753 when N_Object_Declaration =>
5754 Comp := Object_Definition (N);
5757 when N_Function_Specification =>
5758 Comp := Result_Definition (N);
5762 raise Program_Error;
5765 Spec := Access_To_Subprogram_Definition (Acc);
5768 Make_Full_Type_Declaration (Loc,
5769 Defining_Identifier => Anon,
5770 Type_Definition => Copy_Separate_Tree (Spec));
5772 Mark_Rewrite_Insertion (Decl);
5774 -- In ASIS mode, analyze the profile on the original node, because
5775 -- the separate copy does not provide enough links to recover the
5776 -- original tree. Analysis is limited to type annotations, within
5777 -- a temporary scope that serves as an anonymous subprogram to collect
5778 -- otherwise useless temporaries and itypes.
5782 Typ : constant Entity_Id := Make_Temporary (Loc, 'S');
5785 if Nkind (Spec) = N_Access_Function_Definition then
5786 Set_Ekind (Typ, E_Function);
5788 Set_Ekind (Typ, E_Procedure);
5791 Set_Parent (Typ, N);
5792 Set_Scope (Typ, Current_Scope);
5795 -- Nothing to do if procedure is parameterless
5797 if Present (Parameter_Specifications (Spec)) then
5798 Process_Formals (Parameter_Specifications (Spec), Spec);
5801 if Nkind (Spec) = N_Access_Function_Definition then
5803 Def : constant Node_Id := Result_Definition (Spec);
5806 -- The result might itself be an anonymous access type, so
5809 if Nkind (Def) = N_Access_Definition then
5810 if Present (Access_To_Subprogram_Definition (Def)) then
5813 Replace_Anonymous_Access_To_Protected_Subprogram
5816 Find_Type (Subtype_Mark (Def));
5829 -- Insert the new declaration in the nearest enclosing scope. If the
5830 -- node is a body and N is its return type, the declaration belongs in
5831 -- the enclosing scope.
5835 if Nkind (P) = N_Subprogram_Body
5836 and then Nkind (N) = N_Function_Specification
5841 while Present (P) and then not Has_Declarations (P) loop
5845 pragma Assert (Present (P));
5847 if Nkind (P) = N_Package_Specification then
5848 Prepend (Decl, Visible_Declarations (P));
5850 Prepend (Decl, Declarations (P));
5853 -- Replace the anonymous type with an occurrence of the new declaration.
5854 -- In all cases the rewritten node does not have the null-exclusion
5855 -- attribute because (if present) it was already inherited by the
5856 -- anonymous entity (Anon). Thus, in case of components we do not
5857 -- inherit this attribute.
5859 if Nkind (N) = N_Parameter_Specification then
5860 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5861 Set_Etype (Defining_Identifier (N), Anon);
5862 Set_Null_Exclusion_Present (N, False);
5864 elsif Nkind (N) = N_Object_Declaration then
5865 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5866 Set_Etype (Defining_Identifier (N), Anon);
5868 elsif Nkind (N) = N_Access_Function_Definition then
5869 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5871 elsif Nkind (N) = N_Function_Specification then
5872 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5873 Set_Etype (Defining_Unit_Name (N), Anon);
5877 Make_Component_Definition (Loc,
5878 Subtype_Indication => New_Occurrence_Of (Anon, Loc)));
5881 Mark_Rewrite_Insertion (Comp);
5883 if Nkind_In (N, N_Object_Declaration, N_Access_Function_Definition)
5884 or else (Nkind (Parent (N)) = N_Full_Type_Declaration
5885 and then not Is_Type (Current_Scope))
5888 -- Declaration can be analyzed in the current scope.
5893 -- Temporarily remove the current scope (record or subprogram) from
5894 -- the stack to add the new declarations to the enclosing scope.
5895 -- The anonymous entity is an Itype with the proper attributes.
5897 Scope_Stack.Decrement_Last;
5899 Set_Is_Itype (Anon);
5900 Set_Associated_Node_For_Itype (Anon, N);
5901 Scope_Stack.Append (Curr_Scope);
5904 Set_Ekind (Anon, E_Anonymous_Access_Protected_Subprogram_Type);
5905 Set_Can_Use_Internal_Rep (Anon, not Always_Compatible_Rep_On_Target);
5907 end Replace_Anonymous_Access_To_Protected_Subprogram;
5909 -------------------------------
5910 -- Build_Derived_Access_Type --
5911 -------------------------------
5913 procedure Build_Derived_Access_Type
5915 Parent_Type : Entity_Id;
5916 Derived_Type : Entity_Id)
5918 S : constant Node_Id := Subtype_Indication (Type_Definition (N));
5920 Desig_Type : Entity_Id;
5922 Discr_Con_Elist : Elist_Id;
5923 Discr_Con_El : Elmt_Id;
5927 -- Set the designated type so it is available in case this is an access
5928 -- to a self-referential type, e.g. a standard list type with a next
5929 -- pointer. Will be reset after subtype is built.
5931 Set_Directly_Designated_Type
5932 (Derived_Type, Designated_Type (Parent_Type));
5934 Subt := Process_Subtype (S, N);
5936 if Nkind (S) /= N_Subtype_Indication
5937 and then Subt /= Base_Type (Subt)
5939 Set_Ekind (Derived_Type, E_Access_Subtype);
5942 if Ekind (Derived_Type) = E_Access_Subtype then
5944 Pbase : constant Entity_Id := Base_Type (Parent_Type);
5945 Ibase : constant Entity_Id :=
5946 Create_Itype (Ekind (Pbase), N, Derived_Type, 'B');
5947 Svg_Chars : constant Name_Id := Chars (Ibase);
5948 Svg_Next_E : constant Entity_Id := Next_Entity (Ibase);
5951 Copy_Node (Pbase, Ibase);
5953 Set_Chars (Ibase, Svg_Chars);
5954 Set_Next_Entity (Ibase, Svg_Next_E);
5955 Set_Sloc (Ibase, Sloc (Derived_Type));
5956 Set_Scope (Ibase, Scope (Derived_Type));
5957 Set_Freeze_Node (Ibase, Empty);
5958 Set_Is_Frozen (Ibase, False);
5959 Set_Comes_From_Source (Ibase, False);
5960 Set_Is_First_Subtype (Ibase, False);
5962 Set_Etype (Ibase, Pbase);
5963 Set_Etype (Derived_Type, Ibase);
5967 Set_Directly_Designated_Type
5968 (Derived_Type, Designated_Type (Subt));
5970 Set_Is_Constrained (Derived_Type, Is_Constrained (Subt));
5971 Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type));
5972 Set_Size_Info (Derived_Type, Parent_Type);
5973 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
5974 Set_Depends_On_Private (Derived_Type,
5975 Has_Private_Component (Derived_Type));
5976 Conditional_Delay (Derived_Type, Subt);
5978 -- Ada 2005 (AI-231): Set the null-exclusion attribute, and verify
5979 -- that it is not redundant.
5981 if Null_Exclusion_Present (Type_Definition (N)) then
5982 Set_Can_Never_Be_Null (Derived_Type);
5984 -- What is with the "AND THEN FALSE" here ???
5986 if Can_Never_Be_Null (Parent_Type)
5990 ("`NOT NULL` not allowed (& already excludes null)",
5994 elsif Can_Never_Be_Null (Parent_Type) then
5995 Set_Can_Never_Be_Null (Derived_Type);
5998 -- Note: we do not copy the Storage_Size_Variable, since we always go to
5999 -- the root type for this information.
6001 -- Apply range checks to discriminants for derived record case
6002 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
6004 Desig_Type := Designated_Type (Derived_Type);
6005 if Is_Composite_Type (Desig_Type)
6006 and then (not Is_Array_Type (Desig_Type))
6007 and then Has_Discriminants (Desig_Type)
6008 and then Base_Type (Desig_Type) /= Desig_Type
6010 Discr_Con_Elist := Discriminant_Constraint (Desig_Type);
6011 Discr_Con_El := First_Elmt (Discr_Con_Elist);
6013 Discr := First_Discriminant (Base_Type (Desig_Type));
6014 while Present (Discr_Con_El) loop
6015 Apply_Range_Check (Node (Discr_Con_El), Etype (Discr));
6016 Next_Elmt (Discr_Con_El);
6017 Next_Discriminant (Discr);
6020 end Build_Derived_Access_Type;
6022 ------------------------------
6023 -- Build_Derived_Array_Type --
6024 ------------------------------
6026 procedure Build_Derived_Array_Type
6028 Parent_Type : Entity_Id;
6029 Derived_Type : Entity_Id)
6031 Loc : constant Source_Ptr := Sloc (N);
6032 Tdef : constant Node_Id := Type_Definition (N);
6033 Indic : constant Node_Id := Subtype_Indication (Tdef);
6034 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
6035 Implicit_Base : Entity_Id;
6036 New_Indic : Node_Id;
6038 procedure Make_Implicit_Base;
6039 -- If the parent subtype is constrained, the derived type is a subtype
6040 -- of an implicit base type derived from the parent base.
6042 ------------------------
6043 -- Make_Implicit_Base --
6044 ------------------------
6046 procedure Make_Implicit_Base is
6049 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
6051 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
6052 Set_Etype (Implicit_Base, Parent_Base);
6054 Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base);
6055 Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base);
6057 Set_Has_Delayed_Freeze (Implicit_Base, True);
6059 -- Inherit the "ghostness" from the parent base type
6061 if Ghost_Mode > None or else Is_Ghost_Entity (Parent_Base) then
6062 Set_Is_Ghost_Entity (Implicit_Base);
6064 end Make_Implicit_Base;
6066 -- Start of processing for Build_Derived_Array_Type
6069 if not Is_Constrained (Parent_Type) then
6070 if Nkind (Indic) /= N_Subtype_Indication then
6071 Set_Ekind (Derived_Type, E_Array_Type);
6073 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
6074 Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type);
6076 Set_Has_Delayed_Freeze (Derived_Type, True);
6080 Set_Etype (Derived_Type, Implicit_Base);
6083 Make_Subtype_Declaration (Loc,
6084 Defining_Identifier => Derived_Type,
6085 Subtype_Indication =>
6086 Make_Subtype_Indication (Loc,
6087 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6088 Constraint => Constraint (Indic)));
6090 Rewrite (N, New_Indic);
6095 if Nkind (Indic) /= N_Subtype_Indication then
6098 Set_Ekind (Derived_Type, Ekind (Parent_Type));
6099 Set_Etype (Derived_Type, Implicit_Base);
6100 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
6103 Error_Msg_N ("illegal constraint on constrained type", Indic);
6107 -- If parent type is not a derived type itself, and is declared in
6108 -- closed scope (e.g. a subprogram), then we must explicitly introduce
6109 -- the new type's concatenation operator since Derive_Subprograms
6110 -- will not inherit the parent's operator. If the parent type is
6111 -- unconstrained, the operator is of the unconstrained base type.
6113 if Number_Dimensions (Parent_Type) = 1
6114 and then not Is_Limited_Type (Parent_Type)
6115 and then not Is_Derived_Type (Parent_Type)
6116 and then not Is_Package_Or_Generic_Package
6117 (Scope (Base_Type (Parent_Type)))
6119 if not Is_Constrained (Parent_Type)
6120 and then Is_Constrained (Derived_Type)
6122 New_Concatenation_Op (Implicit_Base);
6124 New_Concatenation_Op (Derived_Type);
6127 end Build_Derived_Array_Type;
6129 -----------------------------------
6130 -- Build_Derived_Concurrent_Type --
6131 -----------------------------------
6133 procedure Build_Derived_Concurrent_Type
6135 Parent_Type : Entity_Id;
6136 Derived_Type : Entity_Id)
6138 Loc : constant Source_Ptr := Sloc (N);
6140 Corr_Record : constant Entity_Id := Make_Temporary (Loc, 'C');
6141 Corr_Decl : Node_Id;
6142 Corr_Decl_Needed : Boolean;
6143 -- If the derived type has fewer discriminants than its parent, the
6144 -- corresponding record is also a derived type, in order to account for
6145 -- the bound discriminants. We create a full type declaration for it in
6148 Constraint_Present : constant Boolean :=
6149 Nkind (Subtype_Indication (Type_Definition (N))) =
6150 N_Subtype_Indication;
6152 D_Constraint : Node_Id;
6153 New_Constraint : Elist_Id;
6154 Old_Disc : Entity_Id;
6155 New_Disc : Entity_Id;
6159 Set_Stored_Constraint (Derived_Type, No_Elist);
6160 Corr_Decl_Needed := False;
6163 if Present (Discriminant_Specifications (N))
6164 and then Constraint_Present
6166 Old_Disc := First_Discriminant (Parent_Type);
6167 New_Disc := First (Discriminant_Specifications (N));
6168 while Present (New_Disc) and then Present (Old_Disc) loop
6169 Next_Discriminant (Old_Disc);
6174 if Present (Old_Disc) and then Expander_Active then
6176 -- The new type has fewer discriminants, so we need to create a new
6177 -- corresponding record, which is derived from the corresponding
6178 -- record of the parent, and has a stored constraint that captures
6179 -- the values of the discriminant constraints. The corresponding
6180 -- record is needed only if expander is active and code generation is
6183 -- The type declaration for the derived corresponding record has the
6184 -- same discriminant part and constraints as the current declaration.
6185 -- Copy the unanalyzed tree to build declaration.
6187 Corr_Decl_Needed := True;
6188 New_N := Copy_Separate_Tree (N);
6191 Make_Full_Type_Declaration (Loc,
6192 Defining_Identifier => Corr_Record,
6193 Discriminant_Specifications =>
6194 Discriminant_Specifications (New_N),
6196 Make_Derived_Type_Definition (Loc,
6197 Subtype_Indication =>
6198 Make_Subtype_Indication (Loc,
6201 (Corresponding_Record_Type (Parent_Type), Loc),
6204 (Subtype_Indication (Type_Definition (New_N))))));
6207 -- Copy Storage_Size and Relative_Deadline variables if task case
6209 if Is_Task_Type (Parent_Type) then
6210 Set_Storage_Size_Variable (Derived_Type,
6211 Storage_Size_Variable (Parent_Type));
6212 Set_Relative_Deadline_Variable (Derived_Type,
6213 Relative_Deadline_Variable (Parent_Type));
6216 if Present (Discriminant_Specifications (N)) then
6217 Push_Scope (Derived_Type);
6218 Check_Or_Process_Discriminants (N, Derived_Type);
6220 if Constraint_Present then
6222 Expand_To_Stored_Constraint
6224 Build_Discriminant_Constraints
6226 Subtype_Indication (Type_Definition (N)), True));
6231 elsif Constraint_Present then
6233 -- Build constrained subtype, copying the constraint, and derive
6234 -- from it to create a derived constrained type.
6237 Loc : constant Source_Ptr := Sloc (N);
6238 Anon : constant Entity_Id :=
6239 Make_Defining_Identifier (Loc,
6240 Chars => New_External_Name (Chars (Derived_Type), 'T'));
6245 Make_Subtype_Declaration (Loc,
6246 Defining_Identifier => Anon,
6247 Subtype_Indication =>
6248 New_Copy_Tree (Subtype_Indication (Type_Definition (N))));
6249 Insert_Before (N, Decl);
6252 Rewrite (Subtype_Indication (Type_Definition (N)),
6253 New_Occurrence_Of (Anon, Loc));
6254 Set_Analyzed (Derived_Type, False);
6260 -- By default, operations and private data are inherited from parent.
6261 -- However, in the presence of bound discriminants, a new corresponding
6262 -- record will be created, see below.
6264 Set_Has_Discriminants
6265 (Derived_Type, Has_Discriminants (Parent_Type));
6266 Set_Corresponding_Record_Type
6267 (Derived_Type, Corresponding_Record_Type (Parent_Type));
6269 -- Is_Constrained is set according the parent subtype, but is set to
6270 -- False if the derived type is declared with new discriminants.
6274 (Is_Constrained (Parent_Type) or else Constraint_Present)
6275 and then not Present (Discriminant_Specifications (N)));
6277 if Constraint_Present then
6278 if not Has_Discriminants (Parent_Type) then
6279 Error_Msg_N ("untagged parent must have discriminants", N);
6281 elsif Present (Discriminant_Specifications (N)) then
6283 -- Verify that new discriminants are used to constrain old ones
6288 (Constraint (Subtype_Indication (Type_Definition (N)))));
6290 Old_Disc := First_Discriminant (Parent_Type);
6292 while Present (D_Constraint) loop
6293 if Nkind (D_Constraint) /= N_Discriminant_Association then
6295 -- Positional constraint. If it is a reference to a new
6296 -- discriminant, it constrains the corresponding old one.
6298 if Nkind (D_Constraint) = N_Identifier then
6299 New_Disc := First_Discriminant (Derived_Type);
6300 while Present (New_Disc) loop
6301 exit when Chars (New_Disc) = Chars (D_Constraint);
6302 Next_Discriminant (New_Disc);
6305 if Present (New_Disc) then
6306 Set_Corresponding_Discriminant (New_Disc, Old_Disc);
6310 Next_Discriminant (Old_Disc);
6312 -- if this is a named constraint, search by name for the old
6313 -- discriminants constrained by the new one.
6315 elsif Nkind (Expression (D_Constraint)) = N_Identifier then
6317 -- Find new discriminant with that name
6319 New_Disc := First_Discriminant (Derived_Type);
6320 while Present (New_Disc) loop
6322 Chars (New_Disc) = Chars (Expression (D_Constraint));
6323 Next_Discriminant (New_Disc);
6326 if Present (New_Disc) then
6328 -- Verify that new discriminant renames some discriminant
6329 -- of the parent type, and associate the new discriminant
6330 -- with one or more old ones that it renames.
6336 Selector := First (Selector_Names (D_Constraint));
6337 while Present (Selector) loop
6338 Old_Disc := First_Discriminant (Parent_Type);
6339 while Present (Old_Disc) loop
6340 exit when Chars (Old_Disc) = Chars (Selector);
6341 Next_Discriminant (Old_Disc);
6344 if Present (Old_Disc) then
6345 Set_Corresponding_Discriminant
6346 (New_Disc, Old_Disc);
6355 Next (D_Constraint);
6358 New_Disc := First_Discriminant (Derived_Type);
6359 while Present (New_Disc) loop
6360 if No (Corresponding_Discriminant (New_Disc)) then
6362 ("new discriminant& must constrain old one", N, New_Disc);
6365 Subtypes_Statically_Compatible
6367 Etype (Corresponding_Discriminant (New_Disc)))
6370 ("& not statically compatible with parent discriminant",
6374 Next_Discriminant (New_Disc);
6378 elsif Present (Discriminant_Specifications (N)) then
6380 ("missing discriminant constraint in untagged derivation", N);
6383 -- The entity chain of the derived type includes the new discriminants
6384 -- but shares operations with the parent.
6386 if Present (Discriminant_Specifications (N)) then
6387 Old_Disc := First_Discriminant (Parent_Type);
6388 while Present (Old_Disc) loop
6389 if No (Next_Entity (Old_Disc))
6390 or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant
6393 (Last_Entity (Derived_Type), Next_Entity (Old_Disc));
6397 Next_Discriminant (Old_Disc);
6401 Set_First_Entity (Derived_Type, First_Entity (Parent_Type));
6402 if Has_Discriminants (Parent_Type) then
6403 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6404 Set_Discriminant_Constraint (
6405 Derived_Type, Discriminant_Constraint (Parent_Type));
6409 Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type));
6411 Set_Has_Completion (Derived_Type);
6413 if Corr_Decl_Needed then
6414 Set_Stored_Constraint (Derived_Type, New_Constraint);
6415 Insert_After (N, Corr_Decl);
6416 Analyze (Corr_Decl);
6417 Set_Corresponding_Record_Type (Derived_Type, Corr_Record);
6419 end Build_Derived_Concurrent_Type;
6421 ------------------------------------
6422 -- Build_Derived_Enumeration_Type --
6423 ------------------------------------
6425 procedure Build_Derived_Enumeration_Type
6427 Parent_Type : Entity_Id;
6428 Derived_Type : Entity_Id)
6430 Loc : constant Source_Ptr := Sloc (N);
6431 Def : constant Node_Id := Type_Definition (N);
6432 Indic : constant Node_Id := Subtype_Indication (Def);
6433 Implicit_Base : Entity_Id;
6434 Literal : Entity_Id;
6435 New_Lit : Entity_Id;
6436 Literals_List : List_Id;
6437 Type_Decl : Node_Id;
6439 Rang_Expr : Node_Id;
6442 -- Since types Standard.Character and Standard.[Wide_]Wide_Character do
6443 -- not have explicit literals lists we need to process types derived
6444 -- from them specially. This is handled by Derived_Standard_Character.
6445 -- If the parent type is a generic type, there are no literals either,
6446 -- and we construct the same skeletal representation as for the generic
6449 if Is_Standard_Character_Type (Parent_Type) then
6450 Derived_Standard_Character (N, Parent_Type, Derived_Type);
6452 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
6458 if Nkind (Indic) /= N_Subtype_Indication then
6460 Make_Attribute_Reference (Loc,
6461 Attribute_Name => Name_First,
6462 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6463 Set_Etype (Lo, Derived_Type);
6466 Make_Attribute_Reference (Loc,
6467 Attribute_Name => Name_Last,
6468 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6469 Set_Etype (Hi, Derived_Type);
6471 Set_Scalar_Range (Derived_Type,
6477 -- Analyze subtype indication and verify compatibility
6478 -- with parent type.
6480 if Base_Type (Process_Subtype (Indic, N)) /=
6481 Base_Type (Parent_Type)
6484 ("illegal constraint for formal discrete type", N);
6490 -- If a constraint is present, analyze the bounds to catch
6491 -- premature usage of the derived literals.
6493 if Nkind (Indic) = N_Subtype_Indication
6494 and then Nkind (Range_Expression (Constraint (Indic))) = N_Range
6496 Analyze (Low_Bound (Range_Expression (Constraint (Indic))));
6497 Analyze (High_Bound (Range_Expression (Constraint (Indic))));
6500 -- Introduce an implicit base type for the derived type even if there
6501 -- is no constraint attached to it, since this seems closer to the
6502 -- Ada semantics. Build a full type declaration tree for the derived
6503 -- type using the implicit base type as the defining identifier. The
6504 -- build a subtype declaration tree which applies the constraint (if
6505 -- any) have it replace the derived type declaration.
6507 Literal := First_Literal (Parent_Type);
6508 Literals_List := New_List;
6509 while Present (Literal)
6510 and then Ekind (Literal) = E_Enumeration_Literal
6512 -- Literals of the derived type have the same representation as
6513 -- those of the parent type, but this representation can be
6514 -- overridden by an explicit representation clause. Indicate
6515 -- that there is no explicit representation given yet. These
6516 -- derived literals are implicit operations of the new type,
6517 -- and can be overridden by explicit ones.
6519 if Nkind (Literal) = N_Defining_Character_Literal then
6521 Make_Defining_Character_Literal (Loc, Chars (Literal));
6523 New_Lit := Make_Defining_Identifier (Loc, Chars (Literal));
6526 Set_Ekind (New_Lit, E_Enumeration_Literal);
6527 Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal));
6528 Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal));
6529 Set_Enumeration_Rep_Expr (New_Lit, Empty);
6530 Set_Alias (New_Lit, Literal);
6531 Set_Is_Known_Valid (New_Lit, True);
6533 Append (New_Lit, Literals_List);
6534 Next_Literal (Literal);
6538 Make_Defining_Identifier (Sloc (Derived_Type),
6539 Chars => New_External_Name (Chars (Derived_Type), 'B'));
6541 -- Indicate the proper nature of the derived type. This must be done
6542 -- before analysis of the literals, to recognize cases when a literal
6543 -- may be hidden by a previous explicit function definition (cf.
6546 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
6547 Set_Etype (Derived_Type, Implicit_Base);
6550 Make_Full_Type_Declaration (Loc,
6551 Defining_Identifier => Implicit_Base,
6552 Discriminant_Specifications => No_List,
6554 Make_Enumeration_Type_Definition (Loc, Literals_List));
6556 Mark_Rewrite_Insertion (Type_Decl);
6557 Insert_Before (N, Type_Decl);
6558 Analyze (Type_Decl);
6560 -- The anonymous base now has a full declaration, but this base
6561 -- is not a first subtype.
6563 Set_Is_First_Subtype (Implicit_Base, False);
6565 -- After the implicit base is analyzed its Etype needs to be changed
6566 -- to reflect the fact that it is derived from the parent type which
6567 -- was ignored during analysis. We also set the size at this point.
6569 Set_Etype (Implicit_Base, Parent_Type);
6571 Set_Size_Info (Implicit_Base, Parent_Type);
6572 Set_RM_Size (Implicit_Base, RM_Size (Parent_Type));
6573 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type));
6575 -- Copy other flags from parent type
6577 Set_Has_Non_Standard_Rep
6578 (Implicit_Base, Has_Non_Standard_Rep
6580 Set_Has_Pragma_Ordered
6581 (Implicit_Base, Has_Pragma_Ordered
6583 Set_Has_Delayed_Freeze (Implicit_Base);
6585 -- Process the subtype indication including a validation check on the
6586 -- constraint, if any. If a constraint is given, its bounds must be
6587 -- implicitly converted to the new type.
6589 if Nkind (Indic) = N_Subtype_Indication then
6591 R : constant Node_Id :=
6592 Range_Expression (Constraint (Indic));
6595 if Nkind (R) = N_Range then
6596 Hi := Build_Scalar_Bound
6597 (High_Bound (R), Parent_Type, Implicit_Base);
6598 Lo := Build_Scalar_Bound
6599 (Low_Bound (R), Parent_Type, Implicit_Base);
6602 -- Constraint is a Range attribute. Replace with explicit
6603 -- mention of the bounds of the prefix, which must be a
6606 Analyze (Prefix (R));
6608 Convert_To (Implicit_Base,
6609 Make_Attribute_Reference (Loc,
6610 Attribute_Name => Name_Last,
6612 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6615 Convert_To (Implicit_Base,
6616 Make_Attribute_Reference (Loc,
6617 Attribute_Name => Name_First,
6619 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6626 (Type_High_Bound (Parent_Type),
6627 Parent_Type, Implicit_Base);
6630 (Type_Low_Bound (Parent_Type),
6631 Parent_Type, Implicit_Base);
6639 -- If we constructed a default range for the case where no range
6640 -- was given, then the expressions in the range must not freeze
6641 -- since they do not correspond to expressions in the source.
6643 if Nkind (Indic) /= N_Subtype_Indication then
6644 Set_Must_Not_Freeze (Lo);
6645 Set_Must_Not_Freeze (Hi);
6646 Set_Must_Not_Freeze (Rang_Expr);
6650 Make_Subtype_Declaration (Loc,
6651 Defining_Identifier => Derived_Type,
6652 Subtype_Indication =>
6653 Make_Subtype_Indication (Loc,
6654 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6656 Make_Range_Constraint (Loc,
6657 Range_Expression => Rang_Expr))));
6661 -- Propagate the aspects from the original type declaration to the
6662 -- declaration of the implicit base.
6664 Move_Aspects (From => Original_Node (N), To => Type_Decl);
6666 -- Apply a range check. Since this range expression doesn't have an
6667 -- Etype, we have to specifically pass the Source_Typ parameter. Is
6670 if Nkind (Indic) = N_Subtype_Indication then
6672 (Range_Expression (Constraint (Indic)), Parent_Type,
6673 Source_Typ => Entity (Subtype_Mark (Indic)));
6676 end Build_Derived_Enumeration_Type;
6678 --------------------------------
6679 -- Build_Derived_Numeric_Type --
6680 --------------------------------
6682 procedure Build_Derived_Numeric_Type
6684 Parent_Type : Entity_Id;
6685 Derived_Type : Entity_Id)
6687 Loc : constant Source_Ptr := Sloc (N);
6688 Tdef : constant Node_Id := Type_Definition (N);
6689 Indic : constant Node_Id := Subtype_Indication (Tdef);
6690 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
6691 No_Constraint : constant Boolean := Nkind (Indic) /=
6692 N_Subtype_Indication;
6693 Implicit_Base : Entity_Id;
6699 -- Process the subtype indication including a validation check on
6700 -- the constraint if any.
6702 Discard_Node (Process_Subtype (Indic, N));
6704 -- Introduce an implicit base type for the derived type even if there
6705 -- is no constraint attached to it, since this seems closer to the Ada
6709 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
6711 Set_Etype (Implicit_Base, Parent_Base);
6712 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
6713 Set_Size_Info (Implicit_Base, Parent_Base);
6714 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base));
6715 Set_Parent (Implicit_Base, Parent (Derived_Type));
6716 Set_Is_Known_Valid (Implicit_Base, Is_Known_Valid (Parent_Base));
6718 -- Set RM Size for discrete type or decimal fixed-point type
6719 -- Ordinary fixed-point is excluded, why???
6721 if Is_Discrete_Type (Parent_Base)
6722 or else Is_Decimal_Fixed_Point_Type (Parent_Base)
6724 Set_RM_Size (Implicit_Base, RM_Size (Parent_Base));
6727 Set_Has_Delayed_Freeze (Implicit_Base);
6729 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
6730 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
6732 Set_Scalar_Range (Implicit_Base,
6737 if Has_Infinities (Parent_Base) then
6738 Set_Includes_Infinities (Scalar_Range (Implicit_Base));
6741 -- The Derived_Type, which is the entity of the declaration, is a
6742 -- subtype of the implicit base. Its Ekind is a subtype, even in the
6743 -- absence of an explicit constraint.
6745 Set_Etype (Derived_Type, Implicit_Base);
6747 -- If we did not have a constraint, then the Ekind is set from the
6748 -- parent type (otherwise Process_Subtype has set the bounds)
6750 if No_Constraint then
6751 Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type)));
6754 -- If we did not have a range constraint, then set the range from the
6755 -- parent type. Otherwise, the Process_Subtype call has set the bounds.
6757 if No_Constraint or else not Has_Range_Constraint (Indic) then
6758 Set_Scalar_Range (Derived_Type,
6760 Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)),
6761 High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type))));
6762 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6764 if Has_Infinities (Parent_Type) then
6765 Set_Includes_Infinities (Scalar_Range (Derived_Type));
6768 Set_Is_Known_Valid (Derived_Type, Is_Known_Valid (Parent_Type));
6771 Set_Is_Descendent_Of_Address (Derived_Type,
6772 Is_Descendent_Of_Address (Parent_Type));
6773 Set_Is_Descendent_Of_Address (Implicit_Base,
6774 Is_Descendent_Of_Address (Parent_Type));
6776 -- Set remaining type-specific fields, depending on numeric type
6778 if Is_Modular_Integer_Type (Parent_Type) then
6779 Set_Modulus (Implicit_Base, Modulus (Parent_Base));
6781 Set_Non_Binary_Modulus
6782 (Implicit_Base, Non_Binary_Modulus (Parent_Base));
6785 (Implicit_Base, Is_Known_Valid (Parent_Base));
6787 elsif Is_Floating_Point_Type (Parent_Type) then
6789 -- Digits of base type is always copied from the digits value of
6790 -- the parent base type, but the digits of the derived type will
6791 -- already have been set if there was a constraint present.
6793 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6794 Set_Float_Rep (Implicit_Base, Float_Rep (Parent_Base));
6796 if No_Constraint then
6797 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type));
6800 elsif Is_Fixed_Point_Type (Parent_Type) then
6802 -- Small of base type and derived type are always copied from the
6803 -- parent base type, since smalls never change. The delta of the
6804 -- base type is also copied from the parent base type. However the
6805 -- delta of the derived type will have been set already if a
6806 -- constraint was present.
6808 Set_Small_Value (Derived_Type, Small_Value (Parent_Base));
6809 Set_Small_Value (Implicit_Base, Small_Value (Parent_Base));
6810 Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base));
6812 if No_Constraint then
6813 Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type));
6816 -- The scale and machine radix in the decimal case are always
6817 -- copied from the parent base type.
6819 if Is_Decimal_Fixed_Point_Type (Parent_Type) then
6820 Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base));
6821 Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base));
6823 Set_Machine_Radix_10
6824 (Derived_Type, Machine_Radix_10 (Parent_Base));
6825 Set_Machine_Radix_10
6826 (Implicit_Base, Machine_Radix_10 (Parent_Base));
6828 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6830 if No_Constraint then
6831 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base));
6834 -- the analysis of the subtype_indication sets the
6835 -- digits value of the derived type.
6842 if Is_Integer_Type (Parent_Type) then
6843 Set_Has_Shift_Operator
6844 (Implicit_Base, Has_Shift_Operator (Parent_Type));
6847 -- The type of the bounds is that of the parent type, and they
6848 -- must be converted to the derived type.
6850 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
6852 -- The implicit_base should be frozen when the derived type is frozen,
6853 -- but note that it is used in the conversions of the bounds. For fixed
6854 -- types we delay the determination of the bounds until the proper
6855 -- freezing point. For other numeric types this is rejected by GCC, for
6856 -- reasons that are currently unclear (???), so we choose to freeze the
6857 -- implicit base now. In the case of integers and floating point types
6858 -- this is harmless because subsequent representation clauses cannot
6859 -- affect anything, but it is still baffling that we cannot use the
6860 -- same mechanism for all derived numeric types.
6862 -- There is a further complication: actually some representation
6863 -- clauses can affect the implicit base type. For example, attribute
6864 -- definition clauses for stream-oriented attributes need to set the
6865 -- corresponding TSS entries on the base type, and this normally
6866 -- cannot be done after the base type is frozen, so the circuitry in
6867 -- Sem_Ch13.New_Stream_Subprogram must account for this possibility
6868 -- and not use Set_TSS in this case.
6870 -- There are also consequences for the case of delayed representation
6871 -- aspects for some cases. For example, a Size aspect is delayed and
6872 -- should not be evaluated to the freeze point. This early freezing
6873 -- means that the size attribute evaluation happens too early???
6875 if Is_Fixed_Point_Type (Parent_Type) then
6876 Conditional_Delay (Implicit_Base, Parent_Type);
6878 Freeze_Before (N, Implicit_Base);
6880 end Build_Derived_Numeric_Type;
6882 --------------------------------
6883 -- Build_Derived_Private_Type --
6884 --------------------------------
6886 procedure Build_Derived_Private_Type
6888 Parent_Type : Entity_Id;
6889 Derived_Type : Entity_Id;
6890 Is_Completion : Boolean;
6891 Derive_Subps : Boolean := True)
6893 Loc : constant Source_Ptr := Sloc (N);
6894 Par_Base : constant Entity_Id := Base_Type (Parent_Type);
6895 Par_Scope : constant Entity_Id := Scope (Par_Base);
6896 Full_N : constant Node_Id := New_Copy_Tree (N);
6897 Full_Der : Entity_Id := New_Copy (Derived_Type);
6900 procedure Build_Full_Derivation;
6901 -- Build full derivation, i.e. derive from the full view
6903 procedure Copy_And_Build;
6904 -- Copy derived type declaration, replace parent with its full view,
6905 -- and build derivation
6907 ---------------------------
6908 -- Build_Full_Derivation --
6909 ---------------------------
6911 procedure Build_Full_Derivation is
6913 -- If parent scope is not open, install the declarations
6915 if not In_Open_Scopes (Par_Scope) then
6916 Install_Private_Declarations (Par_Scope);
6917 Install_Visible_Declarations (Par_Scope);
6919 Uninstall_Declarations (Par_Scope);
6921 -- If parent scope is open and in another unit, and parent has a
6922 -- completion, then the derivation is taking place in the visible
6923 -- part of a child unit. In that case retrieve the full view of
6924 -- the parent momentarily.
6926 elsif not In_Same_Source_Unit (N, Parent_Type) then
6927 Full_P := Full_View (Parent_Type);
6928 Exchange_Declarations (Parent_Type);
6930 Exchange_Declarations (Full_P);
6932 -- Otherwise it is a local derivation
6937 end Build_Full_Derivation;
6939 --------------------
6940 -- Copy_And_Build --
6941 --------------------
6943 procedure Copy_And_Build is
6944 Full_Parent : Entity_Id := Parent_Type;
6947 -- If the parent is itself derived from another private type,
6948 -- installing the private declarations has not affected its
6949 -- privacy status, so use its own full view explicitly.
6951 if Is_Private_Type (Full_Parent)
6952 and then Present (Full_View (Full_Parent))
6954 Full_Parent := Full_View (Full_Parent);
6957 -- And its underlying full view if necessary
6959 if Is_Private_Type (Full_Parent)
6960 and then Present (Underlying_Full_View (Full_Parent))
6962 Full_Parent := Underlying_Full_View (Full_Parent);
6965 -- For record, access and most enumeration types, derivation from
6966 -- the full view requires a fully-fledged declaration. In the other
6967 -- cases, just use an itype.
6969 if Ekind (Full_Parent) in Record_Kind
6970 or else Ekind (Full_Parent) in Access_Kind
6972 (Ekind (Full_Parent) in Enumeration_Kind
6973 and then not Is_Standard_Character_Type (Full_Parent)
6974 and then not Is_Generic_Type (Root_Type (Full_Parent)))
6976 -- Copy and adjust declaration to provide a completion for what
6977 -- is originally a private declaration. Indicate that full view
6978 -- is internally generated.
6980 Set_Comes_From_Source (Full_N, False);
6981 Set_Comes_From_Source (Full_Der, False);
6982 Set_Parent (Full_Der, Full_N);
6983 Set_Defining_Identifier (Full_N, Full_Der);
6985 -- If there are no constraints, adjust the subtype mark
6987 if Nkind (Subtype_Indication (Type_Definition (Full_N))) /=
6988 N_Subtype_Indication
6990 Set_Subtype_Indication
6991 (Type_Definition (Full_N),
6992 New_Occurrence_Of (Full_Parent, Sloc (Full_N)));
6995 Insert_After (N, Full_N);
6997 -- Build full view of derived type from full view of parent which
6998 -- is now installed. Subprograms have been derived on the partial
6999 -- view, the completion does not derive them anew.
7001 if Ekind (Full_Parent) in Record_Kind then
7003 -- If parent type is tagged, the completion inherits the proper
7004 -- primitive operations.
7006 if Is_Tagged_Type (Parent_Type) then
7007 Build_Derived_Record_Type
7008 (Full_N, Full_Parent, Full_Der, Derive_Subps);
7010 Build_Derived_Record_Type
7011 (Full_N, Full_Parent, Full_Der, Derive_Subps => False);
7016 (Full_N, Full_Parent, Full_Der,
7017 Is_Completion => False, Derive_Subps => False);
7020 -- The full declaration has been introduced into the tree and
7021 -- processed in the step above. It should not be analyzed again
7022 -- (when encountered later in the current list of declarations)
7023 -- to prevent spurious name conflicts. The full entity remains
7026 Set_Analyzed (Full_N);
7030 Make_Defining_Identifier (Sloc (Derived_Type),
7031 Chars => Chars (Derived_Type));
7032 Set_Is_Itype (Full_Der);
7033 Set_Associated_Node_For_Itype (Full_Der, N);
7034 Set_Parent (Full_Der, N);
7036 (N, Full_Parent, Full_Der,
7037 Is_Completion => False, Derive_Subps => False);
7040 Set_Has_Private_Declaration (Full_Der);
7041 Set_Has_Private_Declaration (Derived_Type);
7043 Set_Scope (Full_Der, Scope (Derived_Type));
7044 Set_Is_First_Subtype (Full_Der, Is_First_Subtype (Derived_Type));
7045 Set_Has_Size_Clause (Full_Der, False);
7046 Set_Has_Alignment_Clause (Full_Der, False);
7047 Set_Has_Delayed_Freeze (Full_Der);
7048 Set_Is_Frozen (Full_Der, False);
7049 Set_Freeze_Node (Full_Der, Empty);
7050 Set_Depends_On_Private (Full_Der, Has_Private_Component (Full_Der));
7051 Set_Is_Public (Full_Der, Is_Public (Derived_Type));
7053 -- The convention on the base type may be set in the private part
7054 -- and not propagated to the subtype until later, so we obtain the
7055 -- convention from the base type of the parent.
7057 Set_Convention (Full_Der, Convention (Base_Type (Full_Parent)));
7060 -- Start of processing for Build_Derived_Private_Type
7063 if Is_Tagged_Type (Parent_Type) then
7064 Full_P := Full_View (Parent_Type);
7066 -- A type extension of a type with unknown discriminants is an
7067 -- indefinite type that the back-end cannot handle directly.
7068 -- We treat it as a private type, and build a completion that is
7069 -- derived from the full view of the parent, and hopefully has
7070 -- known discriminants.
7072 -- If the full view of the parent type has an underlying record view,
7073 -- use it to generate the underlying record view of this derived type
7074 -- (required for chains of derivations with unknown discriminants).
7076 -- Minor optimization: we avoid the generation of useless underlying
7077 -- record view entities if the private type declaration has unknown
7078 -- discriminants but its corresponding full view has no
7081 if Has_Unknown_Discriminants (Parent_Type)
7082 and then Present (Full_P)
7083 and then (Has_Discriminants (Full_P)
7084 or else Present (Underlying_Record_View (Full_P)))
7085 and then not In_Open_Scopes (Par_Scope)
7086 and then Expander_Active
7089 Full_Der : constant Entity_Id := Make_Temporary (Loc, 'T');
7090 New_Ext : constant Node_Id :=
7092 (Record_Extension_Part (Type_Definition (N)));
7096 Build_Derived_Record_Type
7097 (N, Parent_Type, Derived_Type, Derive_Subps);
7099 -- Build anonymous completion, as a derivation from the full
7100 -- view of the parent. This is not a completion in the usual
7101 -- sense, because the current type is not private.
7104 Make_Full_Type_Declaration (Loc,
7105 Defining_Identifier => Full_Der,
7107 Make_Derived_Type_Definition (Loc,
7108 Subtype_Indication =>
7110 (Subtype_Indication (Type_Definition (N))),
7111 Record_Extension_Part => New_Ext));
7113 -- If the parent type has an underlying record view, use it
7114 -- here to build the new underlying record view.
7116 if Present (Underlying_Record_View (Full_P)) then
7118 (Nkind (Subtype_Indication (Type_Definition (Decl)))
7120 Set_Entity (Subtype_Indication (Type_Definition (Decl)),
7121 Underlying_Record_View (Full_P));
7124 Install_Private_Declarations (Par_Scope);
7125 Install_Visible_Declarations (Par_Scope);
7126 Insert_Before (N, Decl);
7128 -- Mark entity as an underlying record view before analysis,
7129 -- to avoid generating the list of its primitive operations
7130 -- (which is not really required for this entity) and thus
7131 -- prevent spurious errors associated with missing overriding
7132 -- of abstract primitives (overridden only for Derived_Type).
7134 Set_Ekind (Full_Der, E_Record_Type);
7135 Set_Is_Underlying_Record_View (Full_Der);
7136 Set_Default_SSO (Full_Der);
7140 pragma Assert (Has_Discriminants (Full_Der)
7141 and then not Has_Unknown_Discriminants (Full_Der));
7143 Uninstall_Declarations (Par_Scope);
7145 -- Freeze the underlying record view, to prevent generation of
7146 -- useless dispatching information, which is simply shared with
7147 -- the real derived type.
7149 Set_Is_Frozen (Full_Der);
7151 -- If the derived type has access discriminants, create
7152 -- references to their anonymous types now, to prevent
7153 -- back-end problems when their first use is in generated
7154 -- bodies of primitives.
7160 E := First_Entity (Full_Der);
7162 while Present (E) loop
7163 if Ekind (E) = E_Discriminant
7164 and then Ekind (Etype (E)) = E_Anonymous_Access_Type
7166 Build_Itype_Reference (Etype (E), Decl);
7173 -- Set up links between real entity and underlying record view
7175 Set_Underlying_Record_View (Derived_Type, Base_Type (Full_Der));
7176 Set_Underlying_Record_View (Base_Type (Full_Der), Derived_Type);
7179 -- If discriminants are known, build derived record
7182 Build_Derived_Record_Type
7183 (N, Parent_Type, Derived_Type, Derive_Subps);
7188 elsif Has_Discriminants (Parent_Type) then
7190 -- Build partial view of derived type from partial view of parent.
7191 -- This must be done before building the full derivation because the
7192 -- second derivation will modify the discriminants of the first and
7193 -- the discriminants are chained with the rest of the components in
7194 -- the full derivation.
7196 Build_Derived_Record_Type
7197 (N, Parent_Type, Derived_Type, Derive_Subps);
7199 -- Build the full derivation if this is not the anonymous derived
7200 -- base type created by Build_Derived_Record_Type in the constrained
7201 -- case (see point 5. of its head comment) since we build it for the
7202 -- derived subtype. And skip it for protected types altogether, as
7203 -- gigi does not use these types directly.
7205 if Present (Full_View (Parent_Type))
7206 and then not Is_Itype (Derived_Type)
7207 and then not (Ekind (Full_View (Parent_Type)) in Protected_Kind)
7210 Der_Base : constant Entity_Id := Base_Type (Derived_Type);
7212 Last_Discr : Entity_Id;
7215 -- If this is not a completion, construct the implicit full
7216 -- view by deriving from the full view of the parent type.
7217 -- But if this is a completion, the derived private type
7218 -- being built is a full view and the full derivation can
7219 -- only be its underlying full view.
7221 Build_Full_Derivation;
7223 if not Is_Completion then
7224 Set_Full_View (Derived_Type, Full_Der);
7226 Set_Underlying_Full_View (Derived_Type, Full_Der);
7229 if not Is_Base_Type (Derived_Type) then
7230 Set_Full_View (Der_Base, Base_Type (Full_Der));
7233 -- Copy the discriminant list from full view to the partial
7234 -- view (base type and its subtype). Gigi requires that the
7235 -- partial and full views have the same discriminants.
7237 -- Note that since the partial view points to discriminants
7238 -- in the full view, their scope will be that of the full
7239 -- view. This might cause some front end problems and need
7242 Discr := First_Discriminant (Base_Type (Full_Der));
7243 Set_First_Entity (Der_Base, Discr);
7246 Last_Discr := Discr;
7247 Next_Discriminant (Discr);
7248 exit when No (Discr);
7251 Set_Last_Entity (Der_Base, Last_Discr);
7252 Set_First_Entity (Derived_Type, First_Entity (Der_Base));
7253 Set_Last_Entity (Derived_Type, Last_Entity (Der_Base));
7255 Set_Stored_Constraint
7256 (Full_Der, Stored_Constraint (Derived_Type));
7260 elsif Present (Full_View (Parent_Type))
7261 and then Has_Discriminants (Full_View (Parent_Type))
7263 if Has_Unknown_Discriminants (Parent_Type)
7264 and then Nkind (Subtype_Indication (Type_Definition (N))) =
7265 N_Subtype_Indication
7268 ("cannot constrain type with unknown discriminants",
7269 Subtype_Indication (Type_Definition (N)));
7273 -- If this is not a completion, construct the implicit full view by
7274 -- deriving from the full view of the parent type. But if this is a
7275 -- completion, the derived private type being built is a full view
7276 -- and the full derivation can only be its underlying full view.
7278 Build_Full_Derivation;
7280 if not Is_Completion then
7281 Set_Full_View (Derived_Type, Full_Der);
7283 Set_Underlying_Full_View (Derived_Type, Full_Der);
7286 -- In any case, the primitive operations are inherited from the
7287 -- parent type, not from the internal full view.
7289 Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type));
7291 if Derive_Subps then
7292 Derive_Subprograms (Parent_Type, Derived_Type);
7295 Set_Stored_Constraint (Derived_Type, No_Elist);
7297 (Derived_Type, Is_Constrained (Full_View (Parent_Type)));
7300 -- Untagged type, No discriminants on either view
7302 if Nkind (Subtype_Indication (Type_Definition (N))) =
7303 N_Subtype_Indication
7306 ("illegal constraint on type without discriminants", N);
7309 if Present (Discriminant_Specifications (N))
7310 and then Present (Full_View (Parent_Type))
7311 and then not Is_Tagged_Type (Full_View (Parent_Type))
7313 Error_Msg_N ("cannot add discriminants to untagged type", N);
7316 Set_Stored_Constraint (Derived_Type, No_Elist);
7317 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
7318 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
7319 Set_Disable_Controlled (Derived_Type, Disable_Controlled
7321 Set_Has_Controlled_Component
7322 (Derived_Type, Has_Controlled_Component
7325 -- Direct controlled types do not inherit Finalize_Storage_Only flag
7327 if not Is_Controlled_Active (Parent_Type) then
7328 Set_Finalize_Storage_Only
7329 (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type));
7332 -- If this is not a completion, construct the implicit full view by
7333 -- deriving from the full view of the parent type.
7335 -- ??? If the parent is untagged private and its completion is
7336 -- tagged, this mechanism will not work because we cannot derive from
7337 -- the tagged full view unless we have an extension.
7339 if Present (Full_View (Parent_Type))
7340 and then not Is_Tagged_Type (Full_View (Parent_Type))
7341 and then not Is_Completion
7343 Build_Full_Derivation;
7344 Set_Full_View (Derived_Type, Full_Der);
7348 Set_Has_Unknown_Discriminants (Derived_Type,
7349 Has_Unknown_Discriminants (Parent_Type));
7351 if Is_Private_Type (Derived_Type) then
7352 Set_Private_Dependents (Derived_Type, New_Elmt_List);
7355 -- If the parent base type is in scope, add the derived type to its
7356 -- list of private dependents, because its full view may become
7357 -- visible subsequently (in a nested private part, a body, or in a
7358 -- further child unit).
7360 if Is_Private_Type (Par_Base) and then In_Open_Scopes (Par_Scope) then
7361 Append_Elmt (Derived_Type, Private_Dependents (Parent_Type));
7363 -- Check for unusual case where a type completed by a private
7364 -- derivation occurs within a package nested in a child unit, and
7365 -- the parent is declared in an ancestor.
7367 if Is_Child_Unit (Scope (Current_Scope))
7368 and then Is_Completion
7369 and then In_Private_Part (Current_Scope)
7370 and then Scope (Parent_Type) /= Current_Scope
7372 -- Note that if the parent has a completion in the private part,
7373 -- (which is itself a derivation from some other private type)
7374 -- it is that completion that is visible, there is no full view
7375 -- available, and no special processing is needed.
7377 and then Present (Full_View (Parent_Type))
7379 -- In this case, the full view of the parent type will become
7380 -- visible in the body of the enclosing child, and only then will
7381 -- the current type be possibly non-private. Build an underlying
7382 -- full view that will be installed when the enclosing child body
7385 if Present (Underlying_Full_View (Derived_Type)) then
7386 Full_Der := Underlying_Full_View (Derived_Type);
7388 Build_Full_Derivation;
7389 Set_Underlying_Full_View (Derived_Type, Full_Der);
7392 -- The full view will be used to swap entities on entry/exit to
7393 -- the body, and must appear in the entity list for the package.
7395 Append_Entity (Full_Der, Scope (Derived_Type));
7398 end Build_Derived_Private_Type;
7400 -------------------------------
7401 -- Build_Derived_Record_Type --
7402 -------------------------------
7406 -- Ideally we would like to use the same model of type derivation for
7407 -- tagged and untagged record types. Unfortunately this is not quite
7408 -- possible because the semantics of representation clauses is different
7409 -- for tagged and untagged records under inheritance. Consider the
7412 -- type R (...) is [tagged] record ... end record;
7413 -- type T (...) is new R (...) [with ...];
7415 -- The representation clauses for T can specify a completely different
7416 -- record layout from R's. Hence the same component can be placed in two
7417 -- very different positions in objects of type T and R. If R and T are
7418 -- tagged types, representation clauses for T can only specify the layout
7419 -- of non inherited components, thus components that are common in R and T
7420 -- have the same position in objects of type R and T.
7422 -- This has two implications. The first is that the entire tree for R's
7423 -- declaration needs to be copied for T in the untagged case, so that T
7424 -- can be viewed as a record type of its own with its own representation
7425 -- clauses. The second implication is the way we handle discriminants.
7426 -- Specifically, in the untagged case we need a way to communicate to Gigi
7427 -- what are the real discriminants in the record, while for the semantics
7428 -- we need to consider those introduced by the user to rename the
7429 -- discriminants in the parent type. This is handled by introducing the
7430 -- notion of stored discriminants. See below for more.
7432 -- Fortunately the way regular components are inherited can be handled in
7433 -- the same way in tagged and untagged types.
7435 -- To complicate things a bit more the private view of a private extension
7436 -- cannot be handled in the same way as the full view (for one thing the
7437 -- semantic rules are somewhat different). We will explain what differs
7440 -- 2. DISCRIMINANTS UNDER INHERITANCE
7442 -- The semantic rules governing the discriminants of derived types are
7445 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
7446 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
7448 -- If parent type has discriminants, then the discriminants that are
7449 -- declared in the derived type are [3.4 (11)]:
7451 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
7454 -- o Otherwise, each discriminant of the parent type (implicitly declared
7455 -- in the same order with the same specifications). In this case, the
7456 -- discriminants are said to be "inherited", or if unknown in the parent
7457 -- are also unknown in the derived type.
7459 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
7461 -- o The parent subtype must be constrained;
7463 -- o If the parent type is not a tagged type, then each discriminant of
7464 -- the derived type must be used in the constraint defining a parent
7465 -- subtype. [Implementation note: This ensures that the new discriminant
7466 -- can share storage with an existing discriminant.]
7468 -- For the derived type each discriminant of the parent type is either
7469 -- inherited, constrained to equal some new discriminant of the derived
7470 -- type, or constrained to the value of an expression.
7472 -- When inherited or constrained to equal some new discriminant, the
7473 -- parent discriminant and the discriminant of the derived type are said
7476 -- If a discriminant of the parent type is constrained to a specific value
7477 -- in the derived type definition, then the discriminant is said to be
7478 -- "specified" by that derived type definition.
7480 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES
7482 -- We have spoken about stored discriminants in point 1 (introduction)
7483 -- above. There are two sort of stored discriminants: implicit and
7484 -- explicit. As long as the derived type inherits the same discriminants as
7485 -- the root record type, stored discriminants are the same as regular
7486 -- discriminants, and are said to be implicit. However, if any discriminant
7487 -- in the root type was renamed in the derived type, then the derived
7488 -- type will contain explicit stored discriminants. Explicit stored
7489 -- discriminants are discriminants in addition to the semantically visible
7490 -- discriminants defined for the derived type. Stored discriminants are
7491 -- used by Gigi to figure out what are the physical discriminants in
7492 -- objects of the derived type (see precise definition in einfo.ads).
7493 -- As an example, consider the following:
7495 -- type R (D1, D2, D3 : Int) is record ... end record;
7496 -- type T1 is new R;
7497 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
7498 -- type T3 is new T2;
7499 -- type T4 (Y : Int) is new T3 (Y, 99);
7501 -- The following table summarizes the discriminants and stored
7502 -- discriminants in R and T1 through T4.
7504 -- Type Discrim Stored Discrim Comment
7505 -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R
7506 -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1
7507 -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2
7508 -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3
7509 -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4
7511 -- Field Corresponding_Discriminant (abbreviated CD below) allows us to
7512 -- find the corresponding discriminant in the parent type, while
7513 -- Original_Record_Component (abbreviated ORC below), the actual physical
7514 -- component that is renamed. Finally the field Is_Completely_Hidden
7515 -- (abbreviated ICH below) is set for all explicit stored discriminants
7516 -- (see einfo.ads for more info). For the above example this gives:
7518 -- Discrim CD ORC ICH
7519 -- ^^^^^^^ ^^ ^^^ ^^^
7520 -- D1 in R empty itself no
7521 -- D2 in R empty itself no
7522 -- D3 in R empty itself no
7524 -- D1 in T1 D1 in R itself no
7525 -- D2 in T1 D2 in R itself no
7526 -- D3 in T1 D3 in R itself no
7528 -- X1 in T2 D3 in T1 D3 in T2 no
7529 -- X2 in T2 D1 in T1 D1 in T2 no
7530 -- D1 in T2 empty itself yes
7531 -- D2 in T2 empty itself yes
7532 -- D3 in T2 empty itself yes
7534 -- X1 in T3 X1 in T2 D3 in T3 no
7535 -- X2 in T3 X2 in T2 D1 in T3 no
7536 -- D1 in T3 empty itself yes
7537 -- D2 in T3 empty itself yes
7538 -- D3 in T3 empty itself yes
7540 -- Y in T4 X1 in T3 D3 in T3 no
7541 -- D1 in T3 empty itself yes
7542 -- D2 in T3 empty itself yes
7543 -- D3 in T3 empty itself yes
7545 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES
7547 -- Type derivation for tagged types is fairly straightforward. If no
7548 -- discriminants are specified by the derived type, these are inherited
7549 -- from the parent. No explicit stored discriminants are ever necessary.
7550 -- The only manipulation that is done to the tree is that of adding a
7551 -- _parent field with parent type and constrained to the same constraint
7552 -- specified for the parent in the derived type definition. For instance:
7554 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
7555 -- type T1 is new R with null record;
7556 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
7558 -- are changed into:
7560 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
7561 -- _parent : R (D1, D2, D3);
7564 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
7565 -- _parent : T1 (X2, 88, X1);
7568 -- The discriminants actually present in R, T1 and T2 as well as their CD,
7569 -- ORC and ICH fields are:
7571 -- Discrim CD ORC ICH
7572 -- ^^^^^^^ ^^ ^^^ ^^^
7573 -- D1 in R empty itself no
7574 -- D2 in R empty itself no
7575 -- D3 in R empty itself no
7577 -- D1 in T1 D1 in R D1 in R no
7578 -- D2 in T1 D2 in R D2 in R no
7579 -- D3 in T1 D3 in R D3 in R no
7581 -- X1 in T2 D3 in T1 D3 in R no
7582 -- X2 in T2 D1 in T1 D1 in R no
7584 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS
7586 -- Regardless of whether we dealing with a tagged or untagged type
7587 -- we will transform all derived type declarations of the form
7589 -- type T is new R (...) [with ...];
7591 -- subtype S is R (...);
7592 -- type T is new S [with ...];
7594 -- type BT is new R [with ...];
7595 -- subtype T is BT (...);
7597 -- That is, the base derived type is constrained only if it has no
7598 -- discriminants. The reason for doing this is that GNAT's semantic model
7599 -- assumes that a base type with discriminants is unconstrained.
7601 -- Note that, strictly speaking, the above transformation is not always
7602 -- correct. Consider for instance the following excerpt from ACVC b34011a:
7604 -- procedure B34011A is
7605 -- type REC (D : integer := 0) is record
7610 -- type T6 is new Rec;
7611 -- function F return T6;
7616 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
7619 -- The definition of Q6.U is illegal. However transforming Q6.U into
7621 -- type BaseU is new T6;
7622 -- subtype U is BaseU (Q6.F.I)
7624 -- turns U into a legal subtype, which is incorrect. To avoid this problem
7625 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
7626 -- the transformation described above.
7628 -- There is another instance where the above transformation is incorrect.
7632 -- type Base (D : Integer) is tagged null record;
7633 -- procedure P (X : Base);
7635 -- type Der is new Base (2) with null record;
7636 -- procedure P (X : Der);
7639 -- Then the above transformation turns this into
7641 -- type Der_Base is new Base with null record;
7642 -- -- procedure P (X : Base) is implicitly inherited here
7643 -- -- as procedure P (X : Der_Base).
7645 -- subtype Der is Der_Base (2);
7646 -- procedure P (X : Der);
7647 -- -- The overriding of P (X : Der_Base) is illegal since we
7648 -- -- have a parameter conformance problem.
7650 -- To get around this problem, after having semantically processed Der_Base
7651 -- and the rewritten subtype declaration for Der, we copy Der_Base field
7652 -- Discriminant_Constraint from Der so that when parameter conformance is
7653 -- checked when P is overridden, no semantic errors are flagged.
7655 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS
7657 -- Regardless of whether we are dealing with a tagged or untagged type
7658 -- we will transform all derived type declarations of the form
7660 -- type R (D1, .., Dn : ...) is [tagged] record ...;
7661 -- type T is new R [with ...];
7663 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
7665 -- The reason for such transformation is that it allows us to implement a
7666 -- very clean form of component inheritance as explained below.
7668 -- Note that this transformation is not achieved by direct tree rewriting
7669 -- and manipulation, but rather by redoing the semantic actions that the
7670 -- above transformation will entail. This is done directly in routine
7671 -- Inherit_Components.
7673 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE
7675 -- In both tagged and untagged derived types, regular non discriminant
7676 -- components are inherited in the derived type from the parent type. In
7677 -- the absence of discriminants component, inheritance is straightforward
7678 -- as components can simply be copied from the parent.
7680 -- If the parent has discriminants, inheriting components constrained with
7681 -- these discriminants requires caution. Consider the following example:
7683 -- type R (D1, D2 : Positive) is [tagged] record
7684 -- S : String (D1 .. D2);
7687 -- type T1 is new R [with null record];
7688 -- type T2 (X : positive) is new R (1, X) [with null record];
7690 -- As explained in 6. above, T1 is rewritten as
7691 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
7692 -- which makes the treatment for T1 and T2 identical.
7694 -- What we want when inheriting S, is that references to D1 and D2 in R are
7695 -- replaced with references to their correct constraints, i.e. D1 and D2 in
7696 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
7697 -- with either discriminant references in the derived type or expressions.
7698 -- This replacement is achieved as follows: before inheriting R's
7699 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
7700 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
7701 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
7702 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
7703 -- by String (1 .. X).
7705 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS
7707 -- We explain here the rules governing private type extensions relevant to
7708 -- type derivation. These rules are explained on the following example:
7710 -- type D [(...)] is new A [(...)] with private; <-- partial view
7711 -- type D [(...)] is new P [(...)] with null record; <-- full view
7713 -- Type A is called the ancestor subtype of the private extension.
7714 -- Type P is the parent type of the full view of the private extension. It
7715 -- must be A or a type derived from A.
7717 -- The rules concerning the discriminants of private type extensions are
7720 -- o If a private extension inherits known discriminants from the ancestor
7721 -- subtype, then the full view must also inherit its discriminants from
7722 -- the ancestor subtype and the parent subtype of the full view must be
7723 -- constrained if and only if the ancestor subtype is constrained.
7725 -- o If a partial view has unknown discriminants, then the full view may
7726 -- define a definite or an indefinite subtype, with or without
7729 -- o If a partial view has neither known nor unknown discriminants, then
7730 -- the full view must define a definite subtype.
7732 -- o If the ancestor subtype of a private extension has constrained
7733 -- discriminants, then the parent subtype of the full view must impose a
7734 -- statically matching constraint on those discriminants.
7736 -- This means that only the following forms of private extensions are
7739 -- type D is new A with private; <-- partial view
7740 -- type D is new P with null record; <-- full view
7742 -- If A has no discriminants than P has no discriminants, otherwise P must
7743 -- inherit A's discriminants.
7745 -- type D is new A (...) with private; <-- partial view
7746 -- type D is new P (:::) with null record; <-- full view
7748 -- P must inherit A's discriminants and (...) and (:::) must statically
7751 -- subtype A is R (...);
7752 -- type D is new A with private; <-- partial view
7753 -- type D is new P with null record; <-- full view
7755 -- P must have inherited R's discriminants and must be derived from A or
7756 -- any of its subtypes.
7758 -- type D (..) is new A with private; <-- partial view
7759 -- type D (..) is new P [(:::)] with null record; <-- full view
7761 -- No specific constraints on P's discriminants or constraint (:::).
7762 -- Note that A can be unconstrained, but the parent subtype P must either
7763 -- be constrained or (:::) must be present.
7765 -- type D (..) is new A [(...)] with private; <-- partial view
7766 -- type D (..) is new P [(:::)] with null record; <-- full view
7768 -- P's constraints on A's discriminants must statically match those
7769 -- imposed by (...).
7771 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS
7773 -- The full view of a private extension is handled exactly as described
7774 -- above. The model chose for the private view of a private extension is
7775 -- the same for what concerns discriminants (i.e. they receive the same
7776 -- treatment as in the tagged case). However, the private view of the
7777 -- private extension always inherits the components of the parent base,
7778 -- without replacing any discriminant reference. Strictly speaking this is
7779 -- incorrect. However, Gigi never uses this view to generate code so this
7780 -- is a purely semantic issue. In theory, a set of transformations similar
7781 -- to those given in 5. and 6. above could be applied to private views of
7782 -- private extensions to have the same model of component inheritance as
7783 -- for non private extensions. However, this is not done because it would
7784 -- further complicate private type processing. Semantically speaking, this
7785 -- leaves us in an uncomfortable situation. As an example consider:
7788 -- type R (D : integer) is tagged record
7789 -- S : String (1 .. D);
7791 -- procedure P (X : R);
7792 -- type T is new R (1) with private;
7794 -- type T is new R (1) with null record;
7797 -- This is transformed into:
7800 -- type R (D : integer) is tagged record
7801 -- S : String (1 .. D);
7803 -- procedure P (X : R);
7804 -- type T is new R (1) with private;
7806 -- type BaseT is new R with null record;
7807 -- subtype T is BaseT (1);
7810 -- (strictly speaking the above is incorrect Ada)
7812 -- From the semantic standpoint the private view of private extension T
7813 -- should be flagged as constrained since one can clearly have
7817 -- in a unit withing Pack. However, when deriving subprograms for the
7818 -- private view of private extension T, T must be seen as unconstrained
7819 -- since T has discriminants (this is a constraint of the current
7820 -- subprogram derivation model). Thus, when processing the private view of
7821 -- a private extension such as T, we first mark T as unconstrained, we
7822 -- process it, we perform program derivation and just before returning from
7823 -- Build_Derived_Record_Type we mark T as constrained.
7825 -- ??? Are there are other uncomfortable cases that we will have to
7828 -- 10. RECORD_TYPE_WITH_PRIVATE complications
7830 -- Types that are derived from a visible record type and have a private
7831 -- extension present other peculiarities. They behave mostly like private
7832 -- types, but if they have primitive operations defined, these will not
7833 -- have the proper signatures for further inheritance, because other
7834 -- primitive operations will use the implicit base that we define for
7835 -- private derivations below. This affect subprogram inheritance (see
7836 -- Derive_Subprograms for details). We also derive the implicit base from
7837 -- the base type of the full view, so that the implicit base is a record
7838 -- type and not another private type, This avoids infinite loops.
7840 procedure Build_Derived_Record_Type
7842 Parent_Type : Entity_Id;
7843 Derived_Type : Entity_Id;
7844 Derive_Subps : Boolean := True)
7846 Discriminant_Specs : constant Boolean :=
7847 Present (Discriminant_Specifications (N));
7848 Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type);
7849 Loc : constant Source_Ptr := Sloc (N);
7850 Private_Extension : constant Boolean :=
7851 Nkind (N) = N_Private_Extension_Declaration;
7852 Assoc_List : Elist_Id;
7853 Constraint_Present : Boolean;
7855 Discrim : Entity_Id;
7857 Inherit_Discrims : Boolean := False;
7858 Last_Discrim : Entity_Id;
7859 New_Base : Entity_Id;
7861 New_Discrs : Elist_Id;
7862 New_Indic : Node_Id;
7863 Parent_Base : Entity_Id;
7864 Save_Etype : Entity_Id;
7865 Save_Discr_Constr : Elist_Id;
7866 Save_Next_Entity : Entity_Id;
7869 Discs : Elist_Id := New_Elmt_List;
7870 -- An empty Discs list means that there were no constraints in the
7871 -- subtype indication or that there was an error processing it.
7874 if Ekind (Parent_Type) = E_Record_Type_With_Private
7875 and then Present (Full_View (Parent_Type))
7876 and then Has_Discriminants (Parent_Type)
7878 Parent_Base := Base_Type (Full_View (Parent_Type));
7880 Parent_Base := Base_Type (Parent_Type);
7883 -- AI05-0115 : if this is a derivation from a private type in some
7884 -- other scope that may lead to invisible components for the derived
7885 -- type, mark it accordingly.
7887 if Is_Private_Type (Parent_Type) then
7888 if Scope (Parent_Type) = Scope (Derived_Type) then
7891 elsif In_Open_Scopes (Scope (Parent_Type))
7892 and then In_Private_Part (Scope (Parent_Type))
7897 Set_Has_Private_Ancestor (Derived_Type);
7901 Set_Has_Private_Ancestor
7902 (Derived_Type, Has_Private_Ancestor (Parent_Type));
7905 -- Before we start the previously documented transformations, here is
7906 -- little fix for size and alignment of tagged types. Normally when we
7907 -- derive type D from type P, we copy the size and alignment of P as the
7908 -- default for D, and in the absence of explicit representation clauses
7909 -- for D, the size and alignment are indeed the same as the parent.
7911 -- But this is wrong for tagged types, since fields may be added, and
7912 -- the default size may need to be larger, and the default alignment may
7913 -- need to be larger.
7915 -- We therefore reset the size and alignment fields in the tagged case.
7916 -- Note that the size and alignment will in any case be at least as
7917 -- large as the parent type (since the derived type has a copy of the
7918 -- parent type in the _parent field)
7920 -- The type is also marked as being tagged here, which is needed when
7921 -- processing components with a self-referential anonymous access type
7922 -- in the call to Check_Anonymous_Access_Components below. Note that
7923 -- this flag is also set later on for completeness.
7926 Set_Is_Tagged_Type (Derived_Type);
7927 Init_Size_Align (Derived_Type);
7930 -- STEP 0a: figure out what kind of derived type declaration we have
7932 if Private_Extension then
7934 Set_Ekind (Derived_Type, E_Record_Type_With_Private);
7935 Set_Default_SSO (Derived_Type);
7938 Type_Def := Type_Definition (N);
7940 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
7941 -- Parent_Base can be a private type or private extension. However,
7942 -- for tagged types with an extension the newly added fields are
7943 -- visible and hence the Derived_Type is always an E_Record_Type.
7944 -- (except that the parent may have its own private fields).
7945 -- For untagged types we preserve the Ekind of the Parent_Base.
7947 if Present (Record_Extension_Part (Type_Def)) then
7948 Set_Ekind (Derived_Type, E_Record_Type);
7949 Set_Default_SSO (Derived_Type);
7951 -- Create internal access types for components with anonymous
7954 if Ada_Version >= Ada_2005 then
7955 Check_Anonymous_Access_Components
7956 (N, Derived_Type, Derived_Type,
7957 Component_List (Record_Extension_Part (Type_Def)));
7961 Set_Ekind (Derived_Type, Ekind (Parent_Base));
7965 -- Indic can either be an N_Identifier if the subtype indication
7966 -- contains no constraint or an N_Subtype_Indication if the subtype
7967 -- indication has a constraint.
7969 Indic := Subtype_Indication (Type_Def);
7970 Constraint_Present := (Nkind (Indic) = N_Subtype_Indication);
7972 -- Check that the type has visible discriminants. The type may be
7973 -- a private type with unknown discriminants whose full view has
7974 -- discriminants which are invisible.
7976 if Constraint_Present then
7977 if not Has_Discriminants (Parent_Base)
7979 (Has_Unknown_Discriminants (Parent_Base)
7980 and then Is_Private_Type (Parent_Base))
7983 ("invalid constraint: type has no discriminant",
7984 Constraint (Indic));
7986 Constraint_Present := False;
7987 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7989 elsif Is_Constrained (Parent_Type) then
7991 ("invalid constraint: parent type is already constrained",
7992 Constraint (Indic));
7994 Constraint_Present := False;
7995 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7999 -- STEP 0b: If needed, apply transformation given in point 5. above
8001 if not Private_Extension
8002 and then Has_Discriminants (Parent_Type)
8003 and then not Discriminant_Specs
8004 and then (Is_Constrained (Parent_Type) or else Constraint_Present)
8006 -- First, we must analyze the constraint (see comment in point 5.)
8007 -- The constraint may come from the subtype indication of the full
8010 if Constraint_Present then
8011 New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic);
8013 -- If there is no explicit constraint, there might be one that is
8014 -- inherited from a constrained parent type. In that case verify that
8015 -- it conforms to the constraint in the partial view. In perverse
8016 -- cases the parent subtypes of the partial and full view can have
8017 -- different constraints.
8019 elsif Present (Stored_Constraint (Parent_Type)) then
8020 New_Discrs := Stored_Constraint (Parent_Type);
8023 New_Discrs := No_Elist;
8026 if Has_Discriminants (Derived_Type)
8027 and then Has_Private_Declaration (Derived_Type)
8028 and then Present (Discriminant_Constraint (Derived_Type))
8029 and then Present (New_Discrs)
8031 -- Verify that constraints of the full view statically match
8032 -- those given in the partial view.
8038 C1 := First_Elmt (New_Discrs);
8039 C2 := First_Elmt (Discriminant_Constraint (Derived_Type));
8040 while Present (C1) and then Present (C2) loop
8041 if Fully_Conformant_Expressions (Node (C1), Node (C2))
8043 (Is_OK_Static_Expression (Node (C1))
8044 and then Is_OK_Static_Expression (Node (C2))
8046 Expr_Value (Node (C1)) = Expr_Value (Node (C2)))
8051 if Constraint_Present then
8053 ("constraint not conformant to previous declaration",
8057 ("constraint of full view is incompatible "
8058 & "with partial view", N);
8068 -- Insert and analyze the declaration for the unconstrained base type
8070 New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B');
8073 Make_Full_Type_Declaration (Loc,
8074 Defining_Identifier => New_Base,
8076 Make_Derived_Type_Definition (Loc,
8077 Abstract_Present => Abstract_Present (Type_Def),
8078 Limited_Present => Limited_Present (Type_Def),
8079 Subtype_Indication =>
8080 New_Occurrence_Of (Parent_Base, Loc),
8081 Record_Extension_Part =>
8082 Relocate_Node (Record_Extension_Part (Type_Def)),
8083 Interface_List => Interface_List (Type_Def)));
8085 Set_Parent (New_Decl, Parent (N));
8086 Mark_Rewrite_Insertion (New_Decl);
8087 Insert_Before (N, New_Decl);
8089 -- In the extension case, make sure ancestor is frozen appropriately
8090 -- (see also non-discriminated case below).
8092 if Present (Record_Extension_Part (Type_Def))
8093 or else Is_Interface (Parent_Base)
8095 Freeze_Before (New_Decl, Parent_Type);
8098 -- Note that this call passes False for the Derive_Subps parameter
8099 -- because subprogram derivation is deferred until after creating
8100 -- the subtype (see below).
8103 (New_Decl, Parent_Base, New_Base,
8104 Is_Completion => False, Derive_Subps => False);
8106 -- ??? This needs re-examination to determine whether the
8107 -- above call can simply be replaced by a call to Analyze.
8109 Set_Analyzed (New_Decl);
8111 -- Insert and analyze the declaration for the constrained subtype
8113 if Constraint_Present then
8115 Make_Subtype_Indication (Loc,
8116 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8117 Constraint => Relocate_Node (Constraint (Indic)));
8121 Constr_List : constant List_Id := New_List;
8126 C := First_Elmt (Discriminant_Constraint (Parent_Type));
8127 while Present (C) loop
8130 -- It is safe here to call New_Copy_Tree since we called
8131 -- Force_Evaluation on each constraint previously
8132 -- in Build_Discriminant_Constraints.
8134 Append (New_Copy_Tree (Expr), To => Constr_List);
8140 Make_Subtype_Indication (Loc,
8141 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8143 Make_Index_Or_Discriminant_Constraint (Loc, Constr_List));
8148 Make_Subtype_Declaration (Loc,
8149 Defining_Identifier => Derived_Type,
8150 Subtype_Indication => New_Indic));
8154 -- Derivation of subprograms must be delayed until the full subtype
8155 -- has been established, to ensure proper overriding of subprograms
8156 -- inherited by full types. If the derivations occurred as part of
8157 -- the call to Build_Derived_Type above, then the check for type
8158 -- conformance would fail because earlier primitive subprograms
8159 -- could still refer to the full type prior the change to the new
8160 -- subtype and hence would not match the new base type created here.
8161 -- Subprograms are not derived, however, when Derive_Subps is False
8162 -- (since otherwise there could be redundant derivations).
8164 if Derive_Subps then
8165 Derive_Subprograms (Parent_Type, Derived_Type);
8168 -- For tagged types the Discriminant_Constraint of the new base itype
8169 -- is inherited from the first subtype so that no subtype conformance
8170 -- problem arise when the first subtype overrides primitive
8171 -- operations inherited by the implicit base type.
8174 Set_Discriminant_Constraint
8175 (New_Base, Discriminant_Constraint (Derived_Type));
8181 -- If we get here Derived_Type will have no discriminants or it will be
8182 -- a discriminated unconstrained base type.
8184 -- STEP 1a: perform preliminary actions/checks for derived tagged types
8188 -- The parent type is frozen for non-private extensions (RM 13.14(7))
8189 -- The declaration of a specific descendant of an interface type
8190 -- freezes the interface type (RM 13.14).
8192 if not Private_Extension or else Is_Interface (Parent_Base) then
8193 Freeze_Before (N, Parent_Type);
8196 -- In Ada 2005 (AI-344), the restriction that a derived tagged type
8197 -- cannot be declared at a deeper level than its parent type is
8198 -- removed. The check on derivation within a generic body is also
8199 -- relaxed, but there's a restriction that a derived tagged type
8200 -- cannot be declared in a generic body if it's derived directly
8201 -- or indirectly from a formal type of that generic.
8203 if Ada_Version >= Ada_2005 then
8204 if Present (Enclosing_Generic_Body (Derived_Type)) then
8206 Ancestor_Type : Entity_Id;
8209 -- Check to see if any ancestor of the derived type is a
8212 Ancestor_Type := Parent_Type;
8213 while not Is_Generic_Type (Ancestor_Type)
8214 and then Etype (Ancestor_Type) /= Ancestor_Type
8216 Ancestor_Type := Etype (Ancestor_Type);
8219 -- If the derived type does have a formal type as an
8220 -- ancestor, then it's an error if the derived type is
8221 -- declared within the body of the generic unit that
8222 -- declares the formal type in its generic formal part. It's
8223 -- sufficient to check whether the ancestor type is declared
8224 -- inside the same generic body as the derived type (such as
8225 -- within a nested generic spec), in which case the
8226 -- derivation is legal. If the formal type is declared
8227 -- outside of that generic body, then it's guaranteed that
8228 -- the derived type is declared within the generic body of
8229 -- the generic unit declaring the formal type.
8231 if Is_Generic_Type (Ancestor_Type)
8232 and then Enclosing_Generic_Body (Ancestor_Type) /=
8233 Enclosing_Generic_Body (Derived_Type)
8236 ("parent type of& must not be descendant of formal type"
8237 & " of an enclosing generic body",
8238 Indic, Derived_Type);
8243 elsif Type_Access_Level (Derived_Type) /=
8244 Type_Access_Level (Parent_Type)
8245 and then not Is_Generic_Type (Derived_Type)
8247 if Is_Controlled (Parent_Type) then
8249 ("controlled type must be declared at the library level",
8253 ("type extension at deeper accessibility level than parent",
8259 GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type);
8262 and then GB /= Enclosing_Generic_Body (Parent_Base)
8265 ("parent type of& must not be outside generic body"
8267 Indic, Derived_Type);
8273 -- Ada 2005 (AI-251)
8275 if Ada_Version >= Ada_2005 and then Is_Tagged then
8277 -- "The declaration of a specific descendant of an interface type
8278 -- freezes the interface type" (RM 13.14).
8283 if Is_Non_Empty_List (Interface_List (Type_Def)) then
8284 Iface := First (Interface_List (Type_Def));
8285 while Present (Iface) loop
8286 Freeze_Before (N, Etype (Iface));
8293 -- STEP 1b : preliminary cleanup of the full view of private types
8295 -- If the type is already marked as having discriminants, then it's the
8296 -- completion of a private type or private extension and we need to
8297 -- retain the discriminants from the partial view if the current
8298 -- declaration has Discriminant_Specifications so that we can verify
8299 -- conformance. However, we must remove any existing components that
8300 -- were inherited from the parent (and attached in Copy_And_Swap)
8301 -- because the full type inherits all appropriate components anyway, and
8302 -- we do not want the partial view's components interfering.
8304 if Has_Discriminants (Derived_Type) and then Discriminant_Specs then
8305 Discrim := First_Discriminant (Derived_Type);
8307 Last_Discrim := Discrim;
8308 Next_Discriminant (Discrim);
8309 exit when No (Discrim);
8312 Set_Last_Entity (Derived_Type, Last_Discrim);
8314 -- In all other cases wipe out the list of inherited components (even
8315 -- inherited discriminants), it will be properly rebuilt here.
8318 Set_First_Entity (Derived_Type, Empty);
8319 Set_Last_Entity (Derived_Type, Empty);
8322 -- STEP 1c: Initialize some flags for the Derived_Type
8324 -- The following flags must be initialized here so that
8325 -- Process_Discriminants can check that discriminants of tagged types do
8326 -- not have a default initial value and that access discriminants are
8327 -- only specified for limited records. For completeness, these flags are
8328 -- also initialized along with all the other flags below.
8330 -- AI-419: Limitedness is not inherited from an interface parent, so to
8331 -- be limited in that case the type must be explicitly declared as
8332 -- limited. However, task and protected interfaces are always limited.
8334 if Limited_Present (Type_Def) then
8335 Set_Is_Limited_Record (Derived_Type);
8337 elsif Is_Limited_Record (Parent_Type)
8338 or else (Present (Full_View (Parent_Type))
8339 and then Is_Limited_Record (Full_View (Parent_Type)))
8341 if not Is_Interface (Parent_Type)
8342 or else Is_Synchronized_Interface (Parent_Type)
8343 or else Is_Protected_Interface (Parent_Type)
8344 or else Is_Task_Interface (Parent_Type)
8346 Set_Is_Limited_Record (Derived_Type);
8350 -- STEP 2a: process discriminants of derived type if any
8352 Push_Scope (Derived_Type);
8354 if Discriminant_Specs then
8355 Set_Has_Unknown_Discriminants (Derived_Type, False);
8357 -- The following call initializes fields Has_Discriminants and
8358 -- Discriminant_Constraint, unless we are processing the completion
8359 -- of a private type declaration.
8361 Check_Or_Process_Discriminants (N, Derived_Type);
8363 -- For untagged types, the constraint on the Parent_Type must be
8364 -- present and is used to rename the discriminants.
8366 if not Is_Tagged and then not Has_Discriminants (Parent_Type) then
8367 Error_Msg_N ("untagged parent must have discriminants", Indic);
8369 elsif not Is_Tagged and then not Constraint_Present then
8371 ("discriminant constraint needed for derived untagged records",
8374 -- Otherwise the parent subtype must be constrained unless we have a
8375 -- private extension.
8377 elsif not Constraint_Present
8378 and then not Private_Extension
8379 and then not Is_Constrained (Parent_Type)
8382 ("unconstrained type not allowed in this context", Indic);
8384 elsif Constraint_Present then
8385 -- The following call sets the field Corresponding_Discriminant
8386 -- for the discriminants in the Derived_Type.
8388 Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True);
8390 -- For untagged types all new discriminants must rename
8391 -- discriminants in the parent. For private extensions new
8392 -- discriminants cannot rename old ones (implied by [7.3(13)]).
8394 Discrim := First_Discriminant (Derived_Type);
8395 while Present (Discrim) loop
8397 and then No (Corresponding_Discriminant (Discrim))
8400 ("new discriminants must constrain old ones", Discrim);
8402 elsif Private_Extension
8403 and then Present (Corresponding_Discriminant (Discrim))
8406 ("only static constraints allowed for parent"
8407 & " discriminants in the partial view", Indic);
8411 -- If a new discriminant is used in the constraint, then its
8412 -- subtype must be statically compatible with the parent
8413 -- discriminant's subtype (3.7(15)).
8415 -- However, if the record contains an array constrained by
8416 -- the discriminant but with some different bound, the compiler
8417 -- attemps to create a smaller range for the discriminant type.
8418 -- (See exp_ch3.Adjust_Discriminants). In this case, where
8419 -- the discriminant type is a scalar type, the check must use
8420 -- the original discriminant type in the parent declaration.
8423 Corr_Disc : constant Entity_Id :=
8424 Corresponding_Discriminant (Discrim);
8425 Disc_Type : constant Entity_Id := Etype (Discrim);
8426 Corr_Type : Entity_Id;
8429 if Present (Corr_Disc) then
8430 if Is_Scalar_Type (Disc_Type) then
8432 Entity (Discriminant_Type (Parent (Corr_Disc)));
8434 Corr_Type := Etype (Corr_Disc);
8438 Subtypes_Statically_Compatible (Disc_Type, Corr_Type)
8441 ("subtype must be compatible "
8442 & "with parent discriminant",
8448 Next_Discriminant (Discrim);
8451 -- Check whether the constraints of the full view statically
8452 -- match those imposed by the parent subtype [7.3(13)].
8454 if Present (Stored_Constraint (Derived_Type)) then
8459 C1 := First_Elmt (Discs);
8460 C2 := First_Elmt (Stored_Constraint (Derived_Type));
8461 while Present (C1) and then Present (C2) loop
8463 Fully_Conformant_Expressions (Node (C1), Node (C2))
8466 ("not conformant with previous declaration",
8477 -- STEP 2b: No new discriminants, inherit discriminants if any
8480 if Private_Extension then
8481 Set_Has_Unknown_Discriminants
8483 Has_Unknown_Discriminants (Parent_Type)
8484 or else Unknown_Discriminants_Present (N));
8486 -- The partial view of the parent may have unknown discriminants,
8487 -- but if the full view has discriminants and the parent type is
8488 -- in scope they must be inherited.
8490 elsif Has_Unknown_Discriminants (Parent_Type)
8492 (not Has_Discriminants (Parent_Type)
8493 or else not In_Open_Scopes (Scope (Parent_Type)))
8495 Set_Has_Unknown_Discriminants (Derived_Type);
8498 if not Has_Unknown_Discriminants (Derived_Type)
8499 and then not Has_Unknown_Discriminants (Parent_Base)
8500 and then Has_Discriminants (Parent_Type)
8502 Inherit_Discrims := True;
8503 Set_Has_Discriminants
8504 (Derived_Type, True);
8505 Set_Discriminant_Constraint
8506 (Derived_Type, Discriminant_Constraint (Parent_Base));
8509 -- The following test is true for private types (remember
8510 -- transformation 5. is not applied to those) and in an error
8513 if Constraint_Present then
8514 Discs := Build_Discriminant_Constraints (Parent_Type, Indic);
8517 -- For now mark a new derived type as constrained only if it has no
8518 -- discriminants. At the end of Build_Derived_Record_Type we properly
8519 -- set this flag in the case of private extensions. See comments in
8520 -- point 9. just before body of Build_Derived_Record_Type.
8524 not (Inherit_Discrims
8525 or else Has_Unknown_Discriminants (Derived_Type)));
8528 -- STEP 3: initialize fields of derived type
8530 Set_Is_Tagged_Type (Derived_Type, Is_Tagged);
8531 Set_Stored_Constraint (Derived_Type, No_Elist);
8533 -- Ada 2005 (AI-251): Private type-declarations can implement interfaces
8534 -- but cannot be interfaces
8536 if not Private_Extension
8537 and then Ekind (Derived_Type) /= E_Private_Type
8538 and then Ekind (Derived_Type) /= E_Limited_Private_Type
8540 if Interface_Present (Type_Def) then
8541 Analyze_Interface_Declaration (Derived_Type, Type_Def);
8544 Set_Interfaces (Derived_Type, No_Elist);
8547 -- Fields inherited from the Parent_Type
8549 Set_Has_Specified_Layout
8550 (Derived_Type, Has_Specified_Layout (Parent_Type));
8551 Set_Is_Limited_Composite
8552 (Derived_Type, Is_Limited_Composite (Parent_Type));
8553 Set_Is_Private_Composite
8554 (Derived_Type, Is_Private_Composite (Parent_Type));
8556 if Is_Tagged_Type (Parent_Type) then
8557 Set_No_Tagged_Streams_Pragma
8558 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
8561 -- Fields inherited from the Parent_Base
8563 Set_Has_Controlled_Component
8564 (Derived_Type, Has_Controlled_Component (Parent_Base));
8565 Set_Has_Non_Standard_Rep
8566 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8567 Set_Has_Primitive_Operations
8568 (Derived_Type, Has_Primitive_Operations (Parent_Base));
8570 -- Fields inherited from the Parent_Base in the non-private case
8572 if Ekind (Derived_Type) = E_Record_Type then
8573 Set_Has_Complex_Representation
8574 (Derived_Type, Has_Complex_Representation (Parent_Base));
8577 -- Fields inherited from the Parent_Base for record types
8579 if Is_Record_Type (Derived_Type) then
8581 Parent_Full : Entity_Id;
8584 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
8585 -- Parent_Base can be a private type or private extension. Go
8586 -- to the full view here to get the E_Record_Type specific flags.
8588 if Present (Full_View (Parent_Base)) then
8589 Parent_Full := Full_View (Parent_Base);
8591 Parent_Full := Parent_Base;
8594 Set_OK_To_Reorder_Components
8595 (Derived_Type, OK_To_Reorder_Components (Parent_Full));
8599 -- Set fields for private derived types
8601 if Is_Private_Type (Derived_Type) then
8602 Set_Depends_On_Private (Derived_Type, True);
8603 Set_Private_Dependents (Derived_Type, New_Elmt_List);
8605 -- Inherit fields from non private record types. If this is the
8606 -- completion of a derivation from a private type, the parent itself
8607 -- is private, and the attributes come from its full view, which must
8611 if Is_Private_Type (Parent_Base)
8612 and then not Is_Record_Type (Parent_Base)
8614 Set_Component_Alignment
8615 (Derived_Type, Component_Alignment (Full_View (Parent_Base)));
8617 (Derived_Type, C_Pass_By_Copy (Full_View (Parent_Base)));
8619 Set_Component_Alignment
8620 (Derived_Type, Component_Alignment (Parent_Base));
8622 (Derived_Type, C_Pass_By_Copy (Parent_Base));
8626 -- Set fields for tagged types
8629 Set_Direct_Primitive_Operations (Derived_Type, New_Elmt_List);
8631 -- All tagged types defined in Ada.Finalization are controlled
8633 if Chars (Scope (Derived_Type)) = Name_Finalization
8634 and then Chars (Scope (Scope (Derived_Type))) = Name_Ada
8635 and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard
8637 Set_Is_Controlled (Derived_Type);
8639 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Base));
8642 -- Minor optimization: there is no need to generate the class-wide
8643 -- entity associated with an underlying record view.
8645 if not Is_Underlying_Record_View (Derived_Type) then
8646 Make_Class_Wide_Type (Derived_Type);
8649 Set_Is_Abstract_Type (Derived_Type, Abstract_Present (Type_Def));
8651 if Has_Discriminants (Derived_Type)
8652 and then Constraint_Present
8654 Set_Stored_Constraint
8655 (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs));
8658 if Ada_Version >= Ada_2005 then
8660 Ifaces_List : Elist_Id;
8663 -- Checks rules 3.9.4 (13/2 and 14/2)
8665 if Comes_From_Source (Derived_Type)
8666 and then not Is_Private_Type (Derived_Type)
8667 and then Is_Interface (Parent_Type)
8668 and then not Is_Interface (Derived_Type)
8670 if Is_Task_Interface (Parent_Type) then
8672 ("(Ada 2005) task type required (RM 3.9.4 (13.2))",
8675 elsif Is_Protected_Interface (Parent_Type) then
8677 ("(Ada 2005) protected type required (RM 3.9.4 (14.2))",
8682 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
8684 Check_Interfaces (N, Type_Def);
8686 -- Ada 2005 (AI-251): Collect the list of progenitors that are
8687 -- not already in the parents.
8691 Ifaces_List => Ifaces_List,
8692 Exclude_Parents => True);
8694 Set_Interfaces (Derived_Type, Ifaces_List);
8696 -- If the derived type is the anonymous type created for
8697 -- a declaration whose parent has a constraint, propagate
8698 -- the interface list to the source type. This must be done
8699 -- prior to the completion of the analysis of the source type
8700 -- because the components in the extension may contain current
8701 -- instances whose legality depends on some ancestor.
8703 if Is_Itype (Derived_Type) then
8705 Def : constant Node_Id :=
8706 Associated_Node_For_Itype (Derived_Type);
8709 and then Nkind (Def) = N_Full_Type_Declaration
8712 (Defining_Identifier (Def), Ifaces_List);
8717 -- Propagate inherited invariant information of parents
8720 if Ada_Version >= Ada_2012
8721 and then not Is_Interface (Derived_Type)
8723 if Has_Inheritable_Invariants (Parent_Type) then
8724 Set_Has_Invariants (Derived_Type);
8725 Set_Has_Inheritable_Invariants (Derived_Type);
8727 elsif not Is_Empty_Elmt_List (Ifaces_List) then
8732 AI := First_Elmt (Ifaces_List);
8733 while Present (AI) loop
8734 if Has_Inheritable_Invariants (Node (AI)) then
8735 Set_Has_Invariants (Derived_Type);
8736 Set_Has_Inheritable_Invariants (Derived_Type);
8747 -- A type extension is automatically Ghost when one of its
8748 -- progenitors is Ghost (SPARK RM 6.9(9)). This property is
8749 -- also inherited when the parent type is Ghost, but this is
8750 -- done in Build_Derived_Type as the mechanism also handles
8751 -- untagged derivations.
8753 if Implements_Ghost_Interface (Derived_Type) then
8754 Set_Is_Ghost_Entity (Derived_Type);
8760 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Base));
8761 Set_Has_Non_Standard_Rep
8762 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8765 -- STEP 4: Inherit components from the parent base and constrain them.
8766 -- Apply the second transformation described in point 6. above.
8768 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
8769 or else not Has_Discriminants (Parent_Type)
8770 or else not Is_Constrained (Parent_Type)
8774 Constrs := Discriminant_Constraint (Parent_Type);
8779 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
8781 -- STEP 5a: Copy the parent record declaration for untagged types
8783 if not Is_Tagged then
8785 -- Discriminant_Constraint (Derived_Type) has been properly
8786 -- constructed. Save it and temporarily set it to Empty because we
8787 -- do not want the call to New_Copy_Tree below to mess this list.
8789 if Has_Discriminants (Derived_Type) then
8790 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
8791 Set_Discriminant_Constraint (Derived_Type, No_Elist);
8793 Save_Discr_Constr := No_Elist;
8796 -- Save the Etype field of Derived_Type. It is correctly set now,
8797 -- but the call to New_Copy tree may remap it to point to itself,
8798 -- which is not what we want. Ditto for the Next_Entity field.
8800 Save_Etype := Etype (Derived_Type);
8801 Save_Next_Entity := Next_Entity (Derived_Type);
8803 -- Assoc_List maps all stored discriminants in the Parent_Base to
8804 -- stored discriminants in the Derived_Type. It is fundamental that
8805 -- no types or itypes with discriminants other than the stored
8806 -- discriminants appear in the entities declared inside
8807 -- Derived_Type, since the back end cannot deal with it.
8811 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
8813 -- Restore the fields saved prior to the New_Copy_Tree call
8814 -- and compute the stored constraint.
8816 Set_Etype (Derived_Type, Save_Etype);
8817 Set_Next_Entity (Derived_Type, Save_Next_Entity);
8819 if Has_Discriminants (Derived_Type) then
8820 Set_Discriminant_Constraint
8821 (Derived_Type, Save_Discr_Constr);
8822 Set_Stored_Constraint
8823 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
8824 Replace_Components (Derived_Type, New_Decl);
8825 Set_Has_Implicit_Dereference
8826 (Derived_Type, Has_Implicit_Dereference (Parent_Type));
8829 -- Insert the new derived type declaration
8831 Rewrite (N, New_Decl);
8833 -- STEP 5b: Complete the processing for record extensions in generics
8835 -- There is no completion for record extensions declared in the
8836 -- parameter part of a generic, so we need to complete processing for
8837 -- these generic record extensions here. The Record_Type_Definition call
8838 -- will change the Ekind of the components from E_Void to E_Component.
8840 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
8841 Record_Type_Definition (Empty, Derived_Type);
8843 -- STEP 5c: Process the record extension for non private tagged types
8845 elsif not Private_Extension then
8846 Expand_Record_Extension (Derived_Type, Type_Def);
8848 -- Note : previously in ASIS mode we set the Parent_Subtype of the
8849 -- derived type to propagate some semantic information. This led
8850 -- to other ASIS failures and has been removed.
8852 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
8853 -- implemented interfaces if we are in expansion mode
8856 and then Has_Interfaces (Derived_Type)
8858 Add_Interface_Tag_Components (N, Derived_Type);
8861 -- Analyze the record extension
8863 Record_Type_Definition
8864 (Record_Extension_Part (Type_Def), Derived_Type);
8869 -- Nothing else to do if there is an error in the derivation.
8870 -- An unusual case: the full view may be derived from a type in an
8871 -- instance, when the partial view was used illegally as an actual
8872 -- in that instance, leading to a circular definition.
8874 if Etype (Derived_Type) = Any_Type
8875 or else Etype (Parent_Type) = Derived_Type
8880 -- Set delayed freeze and then derive subprograms, we need to do
8881 -- this in this order so that derived subprograms inherit the
8882 -- derived freeze if necessary.
8884 Set_Has_Delayed_Freeze (Derived_Type);
8886 if Derive_Subps then
8887 Derive_Subprograms (Parent_Type, Derived_Type);
8890 -- If we have a private extension which defines a constrained derived
8891 -- type mark as constrained here after we have derived subprograms. See
8892 -- comment on point 9. just above the body of Build_Derived_Record_Type.
8894 if Private_Extension and then Inherit_Discrims then
8895 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
8896 Set_Is_Constrained (Derived_Type, True);
8897 Set_Discriminant_Constraint (Derived_Type, Discs);
8899 elsif Is_Constrained (Parent_Type) then
8901 (Derived_Type, True);
8902 Set_Discriminant_Constraint
8903 (Derived_Type, Discriminant_Constraint (Parent_Type));
8907 -- Update the class-wide type, which shares the now-completed entity
8908 -- list with its specific type. In case of underlying record views,
8909 -- we do not generate the corresponding class wide entity.
8912 and then not Is_Underlying_Record_View (Derived_Type)
8915 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
8917 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
8920 Check_Function_Writable_Actuals (N);
8921 end Build_Derived_Record_Type;
8923 ------------------------
8924 -- Build_Derived_Type --
8925 ------------------------
8927 procedure Build_Derived_Type
8929 Parent_Type : Entity_Id;
8930 Derived_Type : Entity_Id;
8931 Is_Completion : Boolean;
8932 Derive_Subps : Boolean := True)
8934 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
8937 -- Set common attributes
8939 Set_Scope (Derived_Type, Current_Scope);
8941 Set_Etype (Derived_Type, Parent_Base);
8942 Set_Ekind (Derived_Type, Ekind (Parent_Base));
8943 Set_Has_Task (Derived_Type, Has_Task (Parent_Base));
8944 Set_Has_Protected (Derived_Type, Has_Protected (Parent_Base));
8946 Set_Size_Info (Derived_Type, Parent_Type);
8947 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
8948 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
8949 Set_Disable_Controlled (Derived_Type, Disable_Controlled (Parent_Type));
8951 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
8952 Set_Is_Volatile (Derived_Type, Is_Volatile (Parent_Type));
8954 if Is_Tagged_Type (Derived_Type) then
8955 Set_No_Tagged_Streams_Pragma
8956 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
8959 -- If the parent has primitive routines, set the derived type link
8961 if Has_Primitive_Operations (Parent_Type) then
8962 Set_Derived_Type_Link (Parent_Base, Derived_Type);
8965 -- If the parent type is a private subtype, the convention on the base
8966 -- type may be set in the private part, and not propagated to the
8967 -- subtype until later, so we obtain the convention from the base type.
8969 Set_Convention (Derived_Type, Convention (Parent_Base));
8971 -- Set SSO default for record or array type
8973 if (Is_Array_Type (Derived_Type) or else Is_Record_Type (Derived_Type))
8974 and then Is_Base_Type (Derived_Type)
8976 Set_Default_SSO (Derived_Type);
8979 -- Propagate invariant information. The new type has invariants if
8980 -- they are inherited from the parent type, and these invariants can
8981 -- be further inherited, so both flags are set.
8983 -- We similarly inherit predicates
8985 if Has_Predicates (Parent_Type) then
8986 Set_Has_Predicates (Derived_Type);
8989 -- The derived type inherits the representation clauses of the parent
8991 Inherit_Rep_Item_Chain (Derived_Type, Parent_Type);
8993 -- Propagate the attributes related to pragma Default_Initial_Condition
8994 -- from the parent type to the private extension. A derived type always
8995 -- inherits the default initial condition flag from the parent type. If
8996 -- the derived type carries its own Default_Initial_Condition pragma,
8997 -- the flag is later reset in Analyze_Pragma. Note that both flags are
8998 -- mutually exclusive.
9000 Propagate_Default_Init_Cond_Attributes
9001 (From_Typ => Parent_Type,
9002 To_Typ => Derived_Type,
9003 Parent_To_Derivation => True);
9005 -- If the parent type has delayed rep aspects, then mark the derived
9006 -- type as possibly inheriting a delayed rep aspect.
9008 if Has_Delayed_Rep_Aspects (Parent_Type) then
9009 Set_May_Inherit_Delayed_Rep_Aspects (Derived_Type);
9012 -- Propagate the attributes related to pragma Ghost from the parent type
9013 -- to the derived type or type extension (SPARK RM 6.9(9)).
9015 if Is_Ghost_Entity (Parent_Type) then
9016 Set_Is_Ghost_Entity (Derived_Type);
9019 -- Type dependent processing
9021 case Ekind (Parent_Type) is
9022 when Numeric_Kind =>
9023 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
9026 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
9030 | Class_Wide_Kind =>
9031 Build_Derived_Record_Type
9032 (N, Parent_Type, Derived_Type, Derive_Subps);
9035 when Enumeration_Kind =>
9036 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
9039 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
9041 when Incomplete_Or_Private_Kind =>
9042 Build_Derived_Private_Type
9043 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
9045 -- For discriminated types, the derivation includes deriving
9046 -- primitive operations. For others it is done below.
9048 if Is_Tagged_Type (Parent_Type)
9049 or else Has_Discriminants (Parent_Type)
9050 or else (Present (Full_View (Parent_Type))
9051 and then Has_Discriminants (Full_View (Parent_Type)))
9056 when Concurrent_Kind =>
9057 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
9060 raise Program_Error;
9063 -- Nothing more to do if some error occurred
9065 if Etype (Derived_Type) = Any_Type then
9069 -- Set delayed freeze and then derive subprograms, we need to do this
9070 -- in this order so that derived subprograms inherit the derived freeze
9073 Set_Has_Delayed_Freeze (Derived_Type);
9075 if Derive_Subps then
9076 Derive_Subprograms (Parent_Type, Derived_Type);
9079 Set_Has_Primitive_Operations
9080 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
9081 end Build_Derived_Type;
9083 -----------------------
9084 -- Build_Discriminal --
9085 -----------------------
9087 procedure Build_Discriminal (Discrim : Entity_Id) is
9088 D_Minal : Entity_Id;
9089 CR_Disc : Entity_Id;
9092 -- A discriminal has the same name as the discriminant
9094 D_Minal := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
9096 Set_Ekind (D_Minal, E_In_Parameter);
9097 Set_Mechanism (D_Minal, Default_Mechanism);
9098 Set_Etype (D_Minal, Etype (Discrim));
9099 Set_Scope (D_Minal, Current_Scope);
9101 Set_Discriminal (Discrim, D_Minal);
9102 Set_Discriminal_Link (D_Minal, Discrim);
9104 -- For task types, build at once the discriminants of the corresponding
9105 -- record, which are needed if discriminants are used in entry defaults
9106 -- and in family bounds.
9108 if Is_Concurrent_Type (Current_Scope)
9110 Is_Limited_Type (Current_Scope)
9112 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
9114 Set_Ekind (CR_Disc, E_In_Parameter);
9115 Set_Mechanism (CR_Disc, Default_Mechanism);
9116 Set_Etype (CR_Disc, Etype (Discrim));
9117 Set_Scope (CR_Disc, Current_Scope);
9118 Set_Discriminal_Link (CR_Disc, Discrim);
9119 Set_CR_Discriminant (Discrim, CR_Disc);
9121 end Build_Discriminal;
9123 ------------------------------------
9124 -- Build_Discriminant_Constraints --
9125 ------------------------------------
9127 function Build_Discriminant_Constraints
9130 Derived_Def : Boolean := False) return Elist_Id
9132 C : constant Node_Id := Constraint (Def);
9133 Nb_Discr : constant Nat := Number_Discriminants (T);
9135 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
9136 -- Saves the expression corresponding to a given discriminant in T
9138 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
9139 -- Return the Position number within array Discr_Expr of a discriminant
9140 -- D within the discriminant list of the discriminated type T.
9142 procedure Process_Discriminant_Expression
9145 -- If this is a discriminant constraint on a partial view, do not
9146 -- generate an overflow check on the discriminant expression. The check
9147 -- will be generated when constraining the full view. Otherwise the
9148 -- backend creates duplicate symbols for the temporaries corresponding
9149 -- to the expressions to be checked, causing spurious assembler errors.
9155 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
9159 Disc := First_Discriminant (T);
9160 for J in Discr_Expr'Range loop
9165 Next_Discriminant (Disc);
9168 -- Note: Since this function is called on discriminants that are
9169 -- known to belong to the discriminated type, falling through the
9170 -- loop with no match signals an internal compiler error.
9172 raise Program_Error;
9175 -------------------------------------
9176 -- Process_Discriminant_Expression --
9177 -------------------------------------
9179 procedure Process_Discriminant_Expression
9183 BDT : constant Entity_Id := Base_Type (Etype (D));
9186 -- If this is a discriminant constraint on a partial view, do
9187 -- not generate an overflow on the discriminant expression. The
9188 -- check will be generated when constraining the full view.
9190 if Is_Private_Type (T)
9191 and then Present (Full_View (T))
9193 Analyze_And_Resolve (Expr, BDT, Suppress => Overflow_Check);
9195 Analyze_And_Resolve (Expr, BDT);
9197 end Process_Discriminant_Expression;
9199 -- Declarations local to Build_Discriminant_Constraints
9203 Elist : constant Elist_Id := New_Elmt_List;
9211 Discrim_Present : Boolean := False;
9213 -- Start of processing for Build_Discriminant_Constraints
9216 -- The following loop will process positional associations only.
9217 -- For a positional association, the (single) discriminant is
9218 -- implicitly specified by position, in textual order (RM 3.7.2).
9220 Discr := First_Discriminant (T);
9221 Constr := First (Constraints (C));
9222 for D in Discr_Expr'Range loop
9223 exit when Nkind (Constr) = N_Discriminant_Association;
9226 Error_Msg_N ("too few discriminants given in constraint", C);
9227 return New_Elmt_List;
9229 elsif Nkind (Constr) = N_Range
9230 or else (Nkind (Constr) = N_Attribute_Reference
9231 and then Attribute_Name (Constr) = Name_Range)
9234 ("a range is not a valid discriminant constraint", Constr);
9235 Discr_Expr (D) := Error;
9238 Process_Discriminant_Expression (Constr, Discr);
9239 Discr_Expr (D) := Constr;
9242 Next_Discriminant (Discr);
9246 if No (Discr) and then Present (Constr) then
9247 Error_Msg_N ("too many discriminants given in constraint", Constr);
9248 return New_Elmt_List;
9251 -- Named associations can be given in any order, but if both positional
9252 -- and named associations are used in the same discriminant constraint,
9253 -- then positional associations must occur first, at their normal
9254 -- position. Hence once a named association is used, the rest of the
9255 -- discriminant constraint must use only named associations.
9257 while Present (Constr) loop
9259 -- Positional association forbidden after a named association
9261 if Nkind (Constr) /= N_Discriminant_Association then
9262 Error_Msg_N ("positional association follows named one", Constr);
9263 return New_Elmt_List;
9265 -- Otherwise it is a named association
9268 -- E records the type of the discriminants in the named
9269 -- association. All the discriminants specified in the same name
9270 -- association must have the same type.
9274 -- Search the list of discriminants in T to see if the simple name
9275 -- given in the constraint matches any of them.
9277 Id := First (Selector_Names (Constr));
9278 while Present (Id) loop
9281 -- If Original_Discriminant is present, we are processing a
9282 -- generic instantiation and this is an instance node. We need
9283 -- to find the name of the corresponding discriminant in the
9284 -- actual record type T and not the name of the discriminant in
9285 -- the generic formal. Example:
9288 -- type G (D : int) is private;
9290 -- subtype W is G (D => 1);
9292 -- type Rec (X : int) is record ... end record;
9293 -- package Q is new P (G => Rec);
9295 -- At the point of the instantiation, formal type G is Rec
9296 -- and therefore when reanalyzing "subtype W is G (D => 1);"
9297 -- which really looks like "subtype W is Rec (D => 1);" at
9298 -- the point of instantiation, we want to find the discriminant
9299 -- that corresponds to D in Rec, i.e. X.
9301 if Present (Original_Discriminant (Id))
9302 and then In_Instance
9304 Discr := Find_Corresponding_Discriminant (Id, T);
9308 Discr := First_Discriminant (T);
9309 while Present (Discr) loop
9310 if Chars (Discr) = Chars (Id) then
9315 Next_Discriminant (Discr);
9319 Error_Msg_N ("& does not match any discriminant", Id);
9320 return New_Elmt_List;
9322 -- If the parent type is a generic formal, preserve the
9323 -- name of the discriminant for subsequent instances.
9324 -- see comment at the beginning of this if statement.
9326 elsif Is_Generic_Type (Root_Type (T)) then
9327 Set_Original_Discriminant (Id, Discr);
9331 Position := Pos_Of_Discr (T, Discr);
9333 if Present (Discr_Expr (Position)) then
9334 Error_Msg_N ("duplicate constraint for discriminant&", Id);
9337 -- Each discriminant specified in the same named association
9338 -- must be associated with a separate copy of the
9339 -- corresponding expression.
9341 if Present (Next (Id)) then
9342 Expr := New_Copy_Tree (Expression (Constr));
9343 Set_Parent (Expr, Parent (Expression (Constr)));
9345 Expr := Expression (Constr);
9348 Discr_Expr (Position) := Expr;
9349 Process_Discriminant_Expression (Expr, Discr);
9352 -- A discriminant association with more than one discriminant
9353 -- name is only allowed if the named discriminants are all of
9354 -- the same type (RM 3.7.1(8)).
9357 E := Base_Type (Etype (Discr));
9359 elsif Base_Type (Etype (Discr)) /= E then
9361 ("all discriminants in an association " &
9362 "must have the same type", Id);
9372 -- A discriminant constraint must provide exactly one value for each
9373 -- discriminant of the type (RM 3.7.1(8)).
9375 for J in Discr_Expr'Range loop
9376 if No (Discr_Expr (J)) then
9377 Error_Msg_N ("too few discriminants given in constraint", C);
9378 return New_Elmt_List;
9382 -- Determine if there are discriminant expressions in the constraint
9384 for J in Discr_Expr'Range loop
9385 if Denotes_Discriminant
9386 (Discr_Expr (J), Check_Concurrent => True)
9388 Discrim_Present := True;
9392 -- Build an element list consisting of the expressions given in the
9393 -- discriminant constraint and apply the appropriate checks. The list
9394 -- is constructed after resolving any named discriminant associations
9395 -- and therefore the expressions appear in the textual order of the
9398 Discr := First_Discriminant (T);
9399 for J in Discr_Expr'Range loop
9400 if Discr_Expr (J) /= Error then
9401 Append_Elmt (Discr_Expr (J), Elist);
9403 -- If any of the discriminant constraints is given by a
9404 -- discriminant and we are in a derived type declaration we
9405 -- have a discriminant renaming. Establish link between new
9406 -- and old discriminant.
9408 if Denotes_Discriminant (Discr_Expr (J)) then
9410 Set_Corresponding_Discriminant
9411 (Entity (Discr_Expr (J)), Discr);
9414 -- Force the evaluation of non-discriminant expressions.
9415 -- If we have found a discriminant in the constraint 3.4(26)
9416 -- and 3.8(18) demand that no range checks are performed are
9417 -- after evaluation. If the constraint is for a component
9418 -- definition that has a per-object constraint, expressions are
9419 -- evaluated but not checked either. In all other cases perform
9423 if Discrim_Present then
9426 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
9428 Has_Per_Object_Constraint
9429 (Defining_Identifier (Parent (Parent (Def))))
9433 elsif Is_Access_Type (Etype (Discr)) then
9434 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
9437 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
9440 Force_Evaluation (Discr_Expr (J));
9443 -- Check that the designated type of an access discriminant's
9444 -- expression is not a class-wide type unless the discriminant's
9445 -- designated type is also class-wide.
9447 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
9448 and then not Is_Class_Wide_Type
9449 (Designated_Type (Etype (Discr)))
9450 and then Etype (Discr_Expr (J)) /= Any_Type
9451 and then Is_Class_Wide_Type
9452 (Designated_Type (Etype (Discr_Expr (J))))
9454 Wrong_Type (Discr_Expr (J), Etype (Discr));
9456 elsif Is_Access_Type (Etype (Discr))
9457 and then not Is_Access_Constant (Etype (Discr))
9458 and then Is_Access_Type (Etype (Discr_Expr (J)))
9459 and then Is_Access_Constant (Etype (Discr_Expr (J)))
9462 ("constraint for discriminant& must be access to variable",
9467 Next_Discriminant (Discr);
9471 end Build_Discriminant_Constraints;
9473 ---------------------------------
9474 -- Build_Discriminated_Subtype --
9475 ---------------------------------
9477 procedure Build_Discriminated_Subtype
9481 Related_Nod : Node_Id;
9482 For_Access : Boolean := False)
9484 Has_Discrs : constant Boolean := Has_Discriminants (T);
9485 Constrained : constant Boolean :=
9487 and then not Is_Empty_Elmt_List (Elist)
9488 and then not Is_Class_Wide_Type (T))
9489 or else Is_Constrained (T);
9492 if Ekind (T) = E_Record_Type then
9494 Set_Ekind (Def_Id, E_Private_Subtype);
9495 Set_Is_For_Access_Subtype (Def_Id, True);
9497 Set_Ekind (Def_Id, E_Record_Subtype);
9500 -- Inherit preelaboration flag from base, for types for which it
9501 -- may have been set: records, private types, protected types.
9503 Set_Known_To_Have_Preelab_Init
9504 (Def_Id, Known_To_Have_Preelab_Init (T));
9506 elsif Ekind (T) = E_Task_Type then
9507 Set_Ekind (Def_Id, E_Task_Subtype);
9509 elsif Ekind (T) = E_Protected_Type then
9510 Set_Ekind (Def_Id, E_Protected_Subtype);
9511 Set_Known_To_Have_Preelab_Init
9512 (Def_Id, Known_To_Have_Preelab_Init (T));
9514 elsif Is_Private_Type (T) then
9515 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
9516 Set_Known_To_Have_Preelab_Init
9517 (Def_Id, Known_To_Have_Preelab_Init (T));
9519 -- Private subtypes may have private dependents
9521 Set_Private_Dependents (Def_Id, New_Elmt_List);
9523 elsif Is_Class_Wide_Type (T) then
9524 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
9527 -- Incomplete type. Attach subtype to list of dependents, to be
9528 -- completed with full view of parent type, unless is it the
9529 -- designated subtype of a record component within an init_proc.
9530 -- This last case arises for a component of an access type whose
9531 -- designated type is incomplete (e.g. a Taft Amendment type).
9532 -- The designated subtype is within an inner scope, and needs no
9533 -- elaboration, because only the access type is needed in the
9534 -- initialization procedure.
9536 Set_Ekind (Def_Id, Ekind (T));
9538 if For_Access and then Within_Init_Proc then
9541 Append_Elmt (Def_Id, Private_Dependents (T));
9545 Set_Etype (Def_Id, T);
9546 Init_Size_Align (Def_Id);
9547 Set_Has_Discriminants (Def_Id, Has_Discrs);
9548 Set_Is_Constrained (Def_Id, Constrained);
9550 Set_First_Entity (Def_Id, First_Entity (T));
9551 Set_Last_Entity (Def_Id, Last_Entity (T));
9552 Set_Has_Implicit_Dereference
9553 (Def_Id, Has_Implicit_Dereference (T));
9555 -- If the subtype is the completion of a private declaration, there may
9556 -- have been representation clauses for the partial view, and they must
9557 -- be preserved. Build_Derived_Type chains the inherited clauses with
9558 -- the ones appearing on the extension. If this comes from a subtype
9559 -- declaration, all clauses are inherited.
9561 if No (First_Rep_Item (Def_Id)) then
9562 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
9565 if Is_Tagged_Type (T) then
9566 Set_Is_Tagged_Type (Def_Id);
9567 Set_No_Tagged_Streams_Pragma (Def_Id, No_Tagged_Streams_Pragma (T));
9568 Make_Class_Wide_Type (Def_Id);
9571 Set_Stored_Constraint (Def_Id, No_Elist);
9574 Set_Discriminant_Constraint (Def_Id, Elist);
9575 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
9578 if Is_Tagged_Type (T) then
9580 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
9581 -- concurrent record type (which has the list of primitive
9584 if Ada_Version >= Ada_2005
9585 and then Is_Concurrent_Type (T)
9587 Set_Corresponding_Record_Type (Def_Id,
9588 Corresponding_Record_Type (T));
9590 Set_Direct_Primitive_Operations (Def_Id,
9591 Direct_Primitive_Operations (T));
9594 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
9597 -- Subtypes introduced by component declarations do not need to be
9598 -- marked as delayed, and do not get freeze nodes, because the semantics
9599 -- verifies that the parents of the subtypes are frozen before the
9600 -- enclosing record is frozen.
9602 if not Is_Type (Scope (Def_Id)) then
9603 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
9605 if Is_Private_Type (T)
9606 and then Present (Full_View (T))
9608 Conditional_Delay (Def_Id, Full_View (T));
9610 Conditional_Delay (Def_Id, T);
9614 if Is_Record_Type (T) then
9615 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
9618 and then not Is_Empty_Elmt_List (Elist)
9619 and then not For_Access
9621 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
9622 elsif not For_Access then
9623 Set_Cloned_Subtype (Def_Id, T);
9626 end Build_Discriminated_Subtype;
9628 ---------------------------
9629 -- Build_Itype_Reference --
9630 ---------------------------
9632 procedure Build_Itype_Reference
9636 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
9639 -- Itype references are only created for use by the back-end
9641 if Inside_A_Generic then
9644 Set_Itype (IR, Ityp);
9645 Insert_After (Nod, IR);
9647 end Build_Itype_Reference;
9649 ------------------------
9650 -- Build_Scalar_Bound --
9651 ------------------------
9653 function Build_Scalar_Bound
9656 Der_T : Entity_Id) return Node_Id
9658 New_Bound : Entity_Id;
9661 -- Note: not clear why this is needed, how can the original bound
9662 -- be unanalyzed at this point? and if it is, what business do we
9663 -- have messing around with it? and why is the base type of the
9664 -- parent type the right type for the resolution. It probably is
9665 -- not. It is OK for the new bound we are creating, but not for
9666 -- the old one??? Still if it never happens, no problem.
9668 Analyze_And_Resolve (Bound, Base_Type (Par_T));
9670 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
9671 New_Bound := New_Copy (Bound);
9672 Set_Etype (New_Bound, Der_T);
9673 Set_Analyzed (New_Bound);
9675 elsif Is_Entity_Name (Bound) then
9676 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
9678 -- The following is almost certainly wrong. What business do we have
9679 -- relocating a node (Bound) that is presumably still attached to
9680 -- the tree elsewhere???
9683 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
9686 Set_Etype (New_Bound, Der_T);
9688 end Build_Scalar_Bound;
9690 --------------------------------
9691 -- Build_Underlying_Full_View --
9692 --------------------------------
9694 procedure Build_Underlying_Full_View
9699 Loc : constant Source_Ptr := Sloc (N);
9700 Subt : constant Entity_Id :=
9701 Make_Defining_Identifier
9702 (Loc, New_External_Name (Chars (Typ), 'S'));
9709 procedure Set_Discriminant_Name (Id : Node_Id);
9710 -- If the derived type has discriminants, they may rename discriminants
9711 -- of the parent. When building the full view of the parent, we need to
9712 -- recover the names of the original discriminants if the constraint is
9713 -- given by named associations.
9715 ---------------------------
9716 -- Set_Discriminant_Name --
9717 ---------------------------
9719 procedure Set_Discriminant_Name (Id : Node_Id) is
9723 Set_Original_Discriminant (Id, Empty);
9725 if Has_Discriminants (Typ) then
9726 Disc := First_Discriminant (Typ);
9727 while Present (Disc) loop
9728 if Chars (Disc) = Chars (Id)
9729 and then Present (Corresponding_Discriminant (Disc))
9731 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
9733 Next_Discriminant (Disc);
9736 end Set_Discriminant_Name;
9738 -- Start of processing for Build_Underlying_Full_View
9741 if Nkind (N) = N_Full_Type_Declaration then
9742 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
9744 elsif Nkind (N) = N_Subtype_Declaration then
9745 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
9747 elsif Nkind (N) = N_Component_Declaration then
9750 (Constraint (Subtype_Indication (Component_Definition (N))));
9753 raise Program_Error;
9756 C := First (Constraints (Constr));
9757 while Present (C) loop
9758 if Nkind (C) = N_Discriminant_Association then
9759 Id := First (Selector_Names (C));
9760 while Present (Id) loop
9761 Set_Discriminant_Name (Id);
9770 Make_Subtype_Declaration (Loc,
9771 Defining_Identifier => Subt,
9772 Subtype_Indication =>
9773 Make_Subtype_Indication (Loc,
9774 Subtype_Mark => New_Occurrence_Of (Par, Loc),
9775 Constraint => New_Copy_Tree (Constr)));
9777 -- If this is a component subtype for an outer itype, it is not
9778 -- a list member, so simply set the parent link for analysis: if
9779 -- the enclosing type does not need to be in a declarative list,
9780 -- neither do the components.
9782 if Is_List_Member (N)
9783 and then Nkind (N) /= N_Component_Declaration
9785 Insert_Before (N, Indic);
9787 Set_Parent (Indic, Parent (N));
9791 Set_Underlying_Full_View (Typ, Full_View (Subt));
9792 end Build_Underlying_Full_View;
9794 -------------------------------
9795 -- Check_Abstract_Overriding --
9796 -------------------------------
9798 procedure Check_Abstract_Overriding (T : Entity_Id) is
9799 Alias_Subp : Entity_Id;
9805 procedure Check_Pragma_Implemented (Subp : Entity_Id);
9806 -- Ada 2012 (AI05-0030): Subprogram Subp overrides an interface routine
9807 -- which has pragma Implemented already set. Check whether Subp's entity
9808 -- kind conforms to the implementation kind of the overridden routine.
9810 procedure Check_Pragma_Implemented
9812 Iface_Subp : Entity_Id);
9813 -- Ada 2012 (AI05-0030): Subprogram Subp overrides interface routine
9814 -- Iface_Subp and both entities have pragma Implemented already set on
9815 -- them. Check whether the two implementation kinds are conforming.
9817 procedure Inherit_Pragma_Implemented
9819 Iface_Subp : Entity_Id);
9820 -- Ada 2012 (AI05-0030): Interface primitive Subp overrides interface
9821 -- subprogram Iface_Subp which has been marked by pragma Implemented.
9822 -- Propagate the implementation kind of Iface_Subp to Subp.
9824 ------------------------------
9825 -- Check_Pragma_Implemented --
9826 ------------------------------
9828 procedure Check_Pragma_Implemented (Subp : Entity_Id) is
9829 Iface_Alias : constant Entity_Id := Interface_Alias (Subp);
9830 Impl_Kind : constant Name_Id := Implementation_Kind (Iface_Alias);
9831 Subp_Alias : constant Entity_Id := Alias (Subp);
9832 Contr_Typ : Entity_Id;
9833 Impl_Subp : Entity_Id;
9836 -- Subp must have an alias since it is a hidden entity used to link
9837 -- an interface subprogram to its overriding counterpart.
9839 pragma Assert (Present (Subp_Alias));
9841 -- Handle aliases to synchronized wrappers
9843 Impl_Subp := Subp_Alias;
9845 if Is_Primitive_Wrapper (Impl_Subp) then
9846 Impl_Subp := Wrapped_Entity (Impl_Subp);
9849 -- Extract the type of the controlling formal
9851 Contr_Typ := Etype (First_Formal (Subp_Alias));
9853 if Is_Concurrent_Record_Type (Contr_Typ) then
9854 Contr_Typ := Corresponding_Concurrent_Type (Contr_Typ);
9857 -- An interface subprogram whose implementation kind is By_Entry must
9858 -- be implemented by an entry.
9860 if Impl_Kind = Name_By_Entry
9861 and then Ekind (Impl_Subp) /= E_Entry
9863 Error_Msg_Node_2 := Iface_Alias;
9865 ("type & must implement abstract subprogram & with an entry",
9866 Subp_Alias, Contr_Typ);
9868 elsif Impl_Kind = Name_By_Protected_Procedure then
9870 -- An interface subprogram whose implementation kind is By_
9871 -- Protected_Procedure cannot be implemented by a primitive
9872 -- procedure of a task type.
9874 if Ekind (Contr_Typ) /= E_Protected_Type then
9875 Error_Msg_Node_2 := Contr_Typ;
9877 ("interface subprogram & cannot be implemented by a " &
9878 "primitive procedure of task type &", Subp_Alias,
9881 -- An interface subprogram whose implementation kind is By_
9882 -- Protected_Procedure must be implemented by a procedure.
9884 elsif Ekind (Impl_Subp) /= E_Procedure then
9885 Error_Msg_Node_2 := Iface_Alias;
9887 ("type & must implement abstract subprogram & with a " &
9888 "procedure", Subp_Alias, Contr_Typ);
9890 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
9891 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
9893 Error_Msg_Name_1 := Impl_Kind;
9895 ("overriding operation& must have synchronization%",
9899 -- If primitive has Optional synchronization, overriding operation
9900 -- must match if it has an explicit synchronization..
9902 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
9903 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
9905 Error_Msg_Name_1 := Impl_Kind;
9907 ("overriding operation& must have syncrhonization%",
9910 end Check_Pragma_Implemented;
9912 ------------------------------
9913 -- Check_Pragma_Implemented --
9914 ------------------------------
9916 procedure Check_Pragma_Implemented
9918 Iface_Subp : Entity_Id)
9920 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
9921 Subp_Kind : constant Name_Id := Implementation_Kind (Subp);
9924 -- Ada 2012 (AI05-0030): The implementation kinds of an overridden
9925 -- and overriding subprogram are different. In general this is an
9926 -- error except when the implementation kind of the overridden
9927 -- subprograms is By_Any or Optional.
9929 if Iface_Kind /= Subp_Kind
9930 and then Iface_Kind /= Name_By_Any
9931 and then Iface_Kind /= Name_Optional
9933 if Iface_Kind = Name_By_Entry then
9935 ("incompatible implementation kind, overridden subprogram " &
9936 "is marked By_Entry", Subp);
9939 ("incompatible implementation kind, overridden subprogram " &
9940 "is marked By_Protected_Procedure", Subp);
9943 end Check_Pragma_Implemented;
9945 --------------------------------
9946 -- Inherit_Pragma_Implemented --
9947 --------------------------------
9949 procedure Inherit_Pragma_Implemented
9951 Iface_Subp : Entity_Id)
9953 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
9954 Loc : constant Source_Ptr := Sloc (Subp);
9955 Impl_Prag : Node_Id;
9958 -- Since the implementation kind is stored as a representation item
9959 -- rather than a flag, create a pragma node.
9963 Chars => Name_Implemented,
9964 Pragma_Argument_Associations => New_List (
9965 Make_Pragma_Argument_Association (Loc,
9966 Expression => New_Occurrence_Of (Subp, Loc)),
9968 Make_Pragma_Argument_Association (Loc,
9969 Expression => Make_Identifier (Loc, Iface_Kind))));
9971 -- The pragma doesn't need to be analyzed because it is internally
9972 -- built. It is safe to directly register it as a rep item since we
9973 -- are only interested in the characters of the implementation kind.
9975 Record_Rep_Item (Subp, Impl_Prag);
9976 end Inherit_Pragma_Implemented;
9978 -- Start of processing for Check_Abstract_Overriding
9981 Op_List := Primitive_Operations (T);
9983 -- Loop to check primitive operations
9985 Elmt := First_Elmt (Op_List);
9986 while Present (Elmt) loop
9987 Subp := Node (Elmt);
9988 Alias_Subp := Alias (Subp);
9990 -- Inherited subprograms are identified by the fact that they do not
9991 -- come from source, and the associated source location is the
9992 -- location of the first subtype of the derived type.
9994 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
9995 -- subprograms that "require overriding".
9997 -- Special exception, do not complain about failure to override the
9998 -- stream routines _Input and _Output, as well as the primitive
9999 -- operations used in dispatching selects since we always provide
10000 -- automatic overridings for these subprograms.
10002 -- The partial view of T may have been a private extension, for
10003 -- which inherited functions dispatching on result are abstract.
10004 -- If the full view is a null extension, there is no need for
10005 -- overriding in Ada 2005, but wrappers need to be built for them
10006 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
10008 if Is_Null_Extension (T)
10009 and then Has_Controlling_Result (Subp)
10010 and then Ada_Version >= Ada_2005
10011 and then Present (Alias_Subp)
10012 and then not Comes_From_Source (Subp)
10013 and then not Is_Abstract_Subprogram (Alias_Subp)
10014 and then not Is_Access_Type (Etype (Subp))
10018 -- Ada 2005 (AI-251): Internal entities of interfaces need no
10019 -- processing because this check is done with the aliased
10022 elsif Present (Interface_Alias (Subp)) then
10025 elsif (Is_Abstract_Subprogram (Subp)
10026 or else Requires_Overriding (Subp)
10028 (Has_Controlling_Result (Subp)
10029 and then Present (Alias_Subp)
10030 and then not Comes_From_Source (Subp)
10031 and then Sloc (Subp) = Sloc (First_Subtype (T))))
10032 and then not Is_TSS (Subp, TSS_Stream_Input)
10033 and then not Is_TSS (Subp, TSS_Stream_Output)
10034 and then not Is_Abstract_Type (T)
10035 and then not Is_Predefined_Interface_Primitive (Subp)
10037 -- Ada 2005 (AI-251): Do not consider hidden entities associated
10038 -- with abstract interface types because the check will be done
10039 -- with the aliased entity (otherwise we generate a duplicated
10042 and then not Present (Interface_Alias (Subp))
10044 if Present (Alias_Subp) then
10046 -- Only perform the check for a derived subprogram when the
10047 -- type has an explicit record extension. This avoids incorrect
10048 -- flagging of abstract subprograms for the case of a type
10049 -- without an extension that is derived from a formal type
10050 -- with a tagged actual (can occur within a private part).
10052 -- Ada 2005 (AI-391): In the case of an inherited function with
10053 -- a controlling result of the type, the rule does not apply if
10054 -- the type is a null extension (unless the parent function
10055 -- itself is abstract, in which case the function must still be
10056 -- be overridden). The expander will generate an overriding
10057 -- wrapper function calling the parent subprogram (see
10058 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
10060 Type_Def := Type_Definition (Parent (T));
10062 if Nkind (Type_Def) = N_Derived_Type_Definition
10063 and then Present (Record_Extension_Part (Type_Def))
10065 (Ada_Version < Ada_2005
10066 or else not Is_Null_Extension (T)
10067 or else Ekind (Subp) = E_Procedure
10068 or else not Has_Controlling_Result (Subp)
10069 or else Is_Abstract_Subprogram (Alias_Subp)
10070 or else Requires_Overriding (Subp)
10071 or else Is_Access_Type (Etype (Subp)))
10073 -- Avoid reporting error in case of abstract predefined
10074 -- primitive inherited from interface type because the
10075 -- body of internally generated predefined primitives
10076 -- of tagged types are generated later by Freeze_Type
10078 if Is_Interface (Root_Type (T))
10079 and then Is_Abstract_Subprogram (Subp)
10080 and then Is_Predefined_Dispatching_Operation (Subp)
10081 and then not Comes_From_Source (Ultimate_Alias (Subp))
10085 -- A null extension is not obliged to override an inherited
10086 -- procedure subject to pragma Extensions_Visible with value
10087 -- False and at least one controlling OUT parameter
10088 -- (SPARK RM 6.1.7(6)).
10090 elsif Is_Null_Extension (T)
10091 and then Is_EVF_Procedure (Subp)
10097 ("type must be declared abstract or & overridden",
10100 -- Traverse the whole chain of aliased subprograms to
10101 -- complete the error notification. This is especially
10102 -- useful for traceability of the chain of entities when
10103 -- the subprogram corresponds with an interface
10104 -- subprogram (which may be defined in another package).
10106 if Present (Alias_Subp) then
10112 while Present (Alias (E)) loop
10114 -- Avoid reporting redundant errors on entities
10115 -- inherited from interfaces
10117 if Sloc (E) /= Sloc (T) then
10118 Error_Msg_Sloc := Sloc (E);
10120 ("\& has been inherited #", T, Subp);
10126 Error_Msg_Sloc := Sloc (E);
10128 -- AI05-0068: report if there is an overriding
10129 -- non-abstract subprogram that is invisible.
10132 and then not Is_Abstract_Subprogram (E)
10135 ("\& subprogram# is not visible",
10138 -- Clarify the case where a non-null extension must
10139 -- override inherited procedure subject to pragma
10140 -- Extensions_Visible with value False and at least
10141 -- one controlling OUT param.
10143 elsif Is_EVF_Procedure (E) then
10145 ("\& # is subject to Extensions_Visible False",
10150 ("\& has been inherited from subprogram #",
10157 -- Ada 2005 (AI-345): Protected or task type implementing
10158 -- abstract interfaces.
10160 elsif Is_Concurrent_Record_Type (T)
10161 and then Present (Interfaces (T))
10163 -- There is no need to check here RM 9.4(11.9/3) since we
10164 -- are processing the corresponding record type and the
10165 -- mode of the overriding subprograms was verified by
10166 -- Check_Conformance when the corresponding concurrent
10167 -- type declaration was analyzed.
10170 ("interface subprogram & must be overridden", T, Subp);
10172 -- Examine primitive operations of synchronized type to find
10173 -- homonyms that have the wrong profile.
10179 Prim := First_Entity (Corresponding_Concurrent_Type (T));
10180 while Present (Prim) loop
10181 if Chars (Prim) = Chars (Subp) then
10183 ("profile is not type conformant with prefixed "
10184 & "view profile of inherited operation&",
10188 Next_Entity (Prim);
10194 Error_Msg_Node_2 := T;
10196 ("abstract subprogram& not allowed for type&", Subp);
10198 -- Also post unconditional warning on the type (unconditional
10199 -- so that if there are more than one of these cases, we get
10200 -- them all, and not just the first one).
10202 Error_Msg_Node_2 := Subp;
10203 Error_Msg_N ("nonabstract type& has abstract subprogram&!", T);
10206 -- A subprogram subject to pragma Extensions_Visible with value
10207 -- "True" cannot override a subprogram subject to the same pragma
10208 -- with value "False" (SPARK RM 6.1.7(5)).
10210 elsif Extensions_Visible_Status (Subp) = Extensions_Visible_True
10211 and then Present (Overridden_Operation (Subp))
10212 and then Extensions_Visible_Status (Overridden_Operation (Subp)) =
10213 Extensions_Visible_False
10215 Error_Msg_Sloc := Sloc (Overridden_Operation (Subp));
10217 ("subprogram & with Extensions_Visible True cannot override "
10218 & "subprogram # with Extensions_Visible False", Subp);
10221 -- Ada 2012 (AI05-0030): Perform checks related to pragma Implemented
10223 -- Subp is an expander-generated procedure which maps an interface
10224 -- alias to a protected wrapper. The interface alias is flagged by
10225 -- pragma Implemented. Ensure that Subp is a procedure when the
10226 -- implementation kind is By_Protected_Procedure or an entry when
10229 if Ada_Version >= Ada_2012
10230 and then Is_Hidden (Subp)
10231 and then Present (Interface_Alias (Subp))
10232 and then Has_Rep_Pragma (Interface_Alias (Subp), Name_Implemented)
10234 Check_Pragma_Implemented (Subp);
10237 -- Subp is an interface primitive which overrides another interface
10238 -- primitive marked with pragma Implemented.
10240 if Ada_Version >= Ada_2012
10241 and then Present (Overridden_Operation (Subp))
10242 and then Has_Rep_Pragma
10243 (Overridden_Operation (Subp), Name_Implemented)
10245 -- If the overriding routine is also marked by Implemented, check
10246 -- that the two implementation kinds are conforming.
10248 if Has_Rep_Pragma (Subp, Name_Implemented) then
10249 Check_Pragma_Implemented
10251 Iface_Subp => Overridden_Operation (Subp));
10253 -- Otherwise the overriding routine inherits the implementation
10254 -- kind from the overridden subprogram.
10257 Inherit_Pragma_Implemented
10259 Iface_Subp => Overridden_Operation (Subp));
10263 -- If the operation is a wrapper for a synchronized primitive, it
10264 -- may be called indirectly through a dispatching select. We assume
10265 -- that it will be referenced elsewhere indirectly, and suppress
10266 -- warnings about an unused entity.
10268 if Is_Primitive_Wrapper (Subp)
10269 and then Present (Wrapped_Entity (Subp))
10271 Set_Referenced (Wrapped_Entity (Subp));
10276 end Check_Abstract_Overriding;
10278 ------------------------------------------------
10279 -- Check_Access_Discriminant_Requires_Limited --
10280 ------------------------------------------------
10282 procedure Check_Access_Discriminant_Requires_Limited
10287 -- A discriminant_specification for an access discriminant shall appear
10288 -- only in the declaration for a task or protected type, or for a type
10289 -- with the reserved word 'limited' in its definition or in one of its
10290 -- ancestors (RM 3.7(10)).
10292 -- AI-0063: The proper condition is that type must be immutably limited,
10293 -- or else be a partial view.
10295 if Nkind (Discriminant_Type (D)) = N_Access_Definition then
10296 if Is_Limited_View (Current_Scope)
10298 (Nkind (Parent (Current_Scope)) = N_Private_Type_Declaration
10299 and then Limited_Present (Parent (Current_Scope)))
10305 ("access discriminants allowed only for limited types", Loc);
10308 end Check_Access_Discriminant_Requires_Limited;
10310 -----------------------------------
10311 -- Check_Aliased_Component_Types --
10312 -----------------------------------
10314 procedure Check_Aliased_Component_Types (T : Entity_Id) is
10318 -- ??? Also need to check components of record extensions, but not
10319 -- components of protected types (which are always limited).
10321 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
10322 -- types to be unconstrained. This is safe because it is illegal to
10323 -- create access subtypes to such types with explicit discriminant
10326 if not Is_Limited_Type (T) then
10327 if Ekind (T) = E_Record_Type then
10328 C := First_Component (T);
10329 while Present (C) loop
10331 and then Has_Discriminants (Etype (C))
10332 and then not Is_Constrained (Etype (C))
10333 and then not In_Instance_Body
10334 and then Ada_Version < Ada_2005
10337 ("aliased component must be constrained (RM 3.6(11))",
10341 Next_Component (C);
10344 elsif Ekind (T) = E_Array_Type then
10345 if Has_Aliased_Components (T)
10346 and then Has_Discriminants (Component_Type (T))
10347 and then not Is_Constrained (Component_Type (T))
10348 and then not In_Instance_Body
10349 and then Ada_Version < Ada_2005
10352 ("aliased component type must be constrained (RM 3.6(11))",
10357 end Check_Aliased_Component_Types;
10359 ---------------------------------------
10360 -- Check_Anonymous_Access_Components --
10361 ---------------------------------------
10363 procedure Check_Anonymous_Access_Components
10364 (Typ_Decl : Node_Id;
10367 Comp_List : Node_Id)
10369 Loc : constant Source_Ptr := Sloc (Typ_Decl);
10370 Anon_Access : Entity_Id;
10373 Comp_Def : Node_Id;
10375 Type_Def : Node_Id;
10377 procedure Build_Incomplete_Type_Declaration;
10378 -- If the record type contains components that include an access to the
10379 -- current record, then create an incomplete type declaration for the
10380 -- record, to be used as the designated type of the anonymous access.
10381 -- This is done only once, and only if there is no previous partial
10382 -- view of the type.
10384 function Designates_T (Subt : Node_Id) return Boolean;
10385 -- Check whether a node designates the enclosing record type, or 'Class
10388 function Mentions_T (Acc_Def : Node_Id) return Boolean;
10389 -- Check whether an access definition includes a reference to
10390 -- the enclosing record type. The reference can be a subtype mark
10391 -- in the access definition itself, a 'Class attribute reference, or
10392 -- recursively a reference appearing in a parameter specification
10393 -- or result definition of an access_to_subprogram definition.
10395 --------------------------------------
10396 -- Build_Incomplete_Type_Declaration --
10397 --------------------------------------
10399 procedure Build_Incomplete_Type_Declaration is
10404 -- Is_Tagged indicates whether the type is tagged. It is tagged if
10405 -- it's "is new ... with record" or else "is tagged record ...".
10407 Is_Tagged : constant Boolean :=
10408 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
10410 Present (Record_Extension_Part (Type_Definition (Typ_Decl))))
10412 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
10413 and then Tagged_Present (Type_Definition (Typ_Decl)));
10416 -- If there is a previous partial view, no need to create a new one
10417 -- If the partial view, given by Prev, is incomplete, If Prev is
10418 -- a private declaration, full declaration is flagged accordingly.
10420 if Prev /= Typ then
10422 Make_Class_Wide_Type (Prev);
10423 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
10424 Set_Etype (Class_Wide_Type (Typ), Typ);
10429 elsif Has_Private_Declaration (Typ) then
10431 -- If we refer to T'Class inside T, and T is the completion of a
10432 -- private type, then make sure the class-wide type exists.
10435 Make_Class_Wide_Type (Typ);
10440 -- If there was a previous anonymous access type, the incomplete
10441 -- type declaration will have been created already.
10443 elsif Present (Current_Entity (Typ))
10444 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
10445 and then Full_View (Current_Entity (Typ)) = Typ
10448 and then Comes_From_Source (Current_Entity (Typ))
10449 and then not Is_Tagged_Type (Current_Entity (Typ))
10451 Make_Class_Wide_Type (Typ);
10453 ("incomplete view of tagged type should be declared tagged??",
10454 Parent (Current_Entity (Typ)));
10459 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
10460 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
10462 -- Type has already been inserted into the current scope. Remove
10463 -- it, and add incomplete declaration for type, so that subsequent
10464 -- anonymous access types can use it. The entity is unchained from
10465 -- the homonym list and from immediate visibility. After analysis,
10466 -- the entity in the incomplete declaration becomes immediately
10467 -- visible in the record declaration that follows.
10469 H := Current_Entity (Typ);
10472 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
10475 and then Homonym (H) /= Typ
10477 H := Homonym (Typ);
10480 Set_Homonym (H, Homonym (Typ));
10483 Insert_Before (Typ_Decl, Decl);
10485 Set_Full_View (Inc_T, Typ);
10489 -- Create a common class-wide type for both views, and set the
10490 -- Etype of the class-wide type to the full view.
10492 Make_Class_Wide_Type (Inc_T);
10493 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
10494 Set_Etype (Class_Wide_Type (Typ), Typ);
10497 end Build_Incomplete_Type_Declaration;
10503 function Designates_T (Subt : Node_Id) return Boolean is
10504 Type_Id : constant Name_Id := Chars (Typ);
10506 function Names_T (Nam : Node_Id) return Boolean;
10507 -- The record type has not been introduced in the current scope
10508 -- yet, so we must examine the name of the type itself, either
10509 -- an identifier T, or an expanded name of the form P.T, where
10510 -- P denotes the current scope.
10516 function Names_T (Nam : Node_Id) return Boolean is
10518 if Nkind (Nam) = N_Identifier then
10519 return Chars (Nam) = Type_Id;
10521 elsif Nkind (Nam) = N_Selected_Component then
10522 if Chars (Selector_Name (Nam)) = Type_Id then
10523 if Nkind (Prefix (Nam)) = N_Identifier then
10524 return Chars (Prefix (Nam)) = Chars (Current_Scope);
10526 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
10527 return Chars (Selector_Name (Prefix (Nam))) =
10528 Chars (Current_Scope);
10542 -- Start of processing for Designates_T
10545 if Nkind (Subt) = N_Identifier then
10546 return Chars (Subt) = Type_Id;
10548 -- Reference can be through an expanded name which has not been
10549 -- analyzed yet, and which designates enclosing scopes.
10551 elsif Nkind (Subt) = N_Selected_Component then
10552 if Names_T (Subt) then
10555 -- Otherwise it must denote an entity that is already visible.
10556 -- The access definition may name a subtype of the enclosing
10557 -- type, if there is a previous incomplete declaration for it.
10560 Find_Selected_Component (Subt);
10562 Is_Entity_Name (Subt)
10563 and then Scope (Entity (Subt)) = Current_Scope
10565 (Chars (Base_Type (Entity (Subt))) = Type_Id
10567 (Is_Class_Wide_Type (Entity (Subt))
10569 Chars (Etype (Base_Type (Entity (Subt)))) =
10573 -- A reference to the current type may appear as the prefix of
10574 -- a 'Class attribute.
10576 elsif Nkind (Subt) = N_Attribute_Reference
10577 and then Attribute_Name (Subt) = Name_Class
10579 return Names_T (Prefix (Subt));
10590 function Mentions_T (Acc_Def : Node_Id) return Boolean is
10591 Param_Spec : Node_Id;
10593 Acc_Subprg : constant Node_Id :=
10594 Access_To_Subprogram_Definition (Acc_Def);
10597 if No (Acc_Subprg) then
10598 return Designates_T (Subtype_Mark (Acc_Def));
10601 -- Component is an access_to_subprogram: examine its formals,
10602 -- and result definition in the case of an access_to_function.
10604 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
10605 while Present (Param_Spec) loop
10606 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
10607 and then Mentions_T (Parameter_Type (Param_Spec))
10611 elsif Designates_T (Parameter_Type (Param_Spec)) then
10618 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
10619 if Nkind (Result_Definition (Acc_Subprg)) =
10620 N_Access_Definition
10622 return Mentions_T (Result_Definition (Acc_Subprg));
10624 return Designates_T (Result_Definition (Acc_Subprg));
10631 -- Start of processing for Check_Anonymous_Access_Components
10634 if No (Comp_List) then
10638 Comp := First (Component_Items (Comp_List));
10639 while Present (Comp) loop
10640 if Nkind (Comp) = N_Component_Declaration
10642 (Access_Definition (Component_Definition (Comp)))
10644 Mentions_T (Access_Definition (Component_Definition (Comp)))
10646 Comp_Def := Component_Definition (Comp);
10648 Access_To_Subprogram_Definition (Access_Definition (Comp_Def));
10650 Build_Incomplete_Type_Declaration;
10651 Anon_Access := Make_Temporary (Loc, 'S');
10653 -- Create a declaration for the anonymous access type: either
10654 -- an access_to_object or an access_to_subprogram.
10656 if Present (Acc_Def) then
10657 if Nkind (Acc_Def) = N_Access_Function_Definition then
10659 Make_Access_Function_Definition (Loc,
10660 Parameter_Specifications =>
10661 Parameter_Specifications (Acc_Def),
10662 Result_Definition => Result_Definition (Acc_Def));
10665 Make_Access_Procedure_Definition (Loc,
10666 Parameter_Specifications =>
10667 Parameter_Specifications (Acc_Def));
10672 Make_Access_To_Object_Definition (Loc,
10673 Subtype_Indication =>
10675 (Subtype_Mark (Access_Definition (Comp_Def))));
10677 Set_Constant_Present
10678 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
10680 (Type_Def, All_Present (Access_Definition (Comp_Def)));
10683 Set_Null_Exclusion_Present
10685 Null_Exclusion_Present (Access_Definition (Comp_Def)));
10688 Make_Full_Type_Declaration (Loc,
10689 Defining_Identifier => Anon_Access,
10690 Type_Definition => Type_Def);
10692 Insert_Before (Typ_Decl, Decl);
10695 -- If an access to subprogram, create the extra formals
10697 if Present (Acc_Def) then
10698 Create_Extra_Formals (Designated_Type (Anon_Access));
10700 -- If an access to object, preserve entity of designated type,
10701 -- for ASIS use, before rewriting the component definition.
10708 Desig := Entity (Subtype_Indication (Type_Def));
10710 -- If the access definition is to the current record,
10711 -- the visible entity at this point is an incomplete
10712 -- type. Retrieve the full view to simplify ASIS queries
10714 if Ekind (Desig) = E_Incomplete_Type then
10715 Desig := Full_View (Desig);
10719 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
10724 Make_Component_Definition (Loc,
10725 Subtype_Indication =>
10726 New_Occurrence_Of (Anon_Access, Loc)));
10728 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
10729 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
10731 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
10734 Set_Is_Local_Anonymous_Access (Anon_Access);
10740 if Present (Variant_Part (Comp_List)) then
10744 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
10745 while Present (V) loop
10746 Check_Anonymous_Access_Components
10747 (Typ_Decl, Typ, Prev, Component_List (V));
10748 Next_Non_Pragma (V);
10752 end Check_Anonymous_Access_Components;
10754 ----------------------
10755 -- Check_Completion --
10756 ----------------------
10758 procedure Check_Completion (Body_Id : Node_Id := Empty) is
10761 procedure Post_Error;
10762 -- Post error message for lack of completion for entity E
10768 procedure Post_Error is
10769 procedure Missing_Body;
10770 -- Output missing body message
10776 procedure Missing_Body is
10778 -- Spec is in same unit, so we can post on spec
10780 if In_Same_Source_Unit (Body_Id, E) then
10781 Error_Msg_N ("missing body for &", E);
10783 -- Spec is in a separate unit, so we have to post on the body
10786 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
10790 -- Start of processing for Post_Error
10793 if not Comes_From_Source (E) then
10794 if Ekind_In (E, E_Task_Type, E_Protected_Type) then
10796 -- It may be an anonymous protected type created for a
10797 -- single variable. Post error on variable, if present.
10803 Var := First_Entity (Current_Scope);
10804 while Present (Var) loop
10805 exit when Etype (Var) = E
10806 and then Comes_From_Source (Var);
10811 if Present (Var) then
10818 -- If a generated entity has no completion, then either previous
10819 -- semantic errors have disabled the expansion phase, or else we had
10820 -- missing subunits, or else we are compiling without expansion,
10821 -- or else something is very wrong.
10823 if not Comes_From_Source (E) then
10825 (Serious_Errors_Detected > 0
10826 or else Configurable_Run_Time_Violations > 0
10827 or else Subunits_Missing
10828 or else not Expander_Active);
10831 -- Here for source entity
10834 -- Here if no body to post the error message, so we post the error
10835 -- on the declaration that has no completion. This is not really
10836 -- the right place to post it, think about this later ???
10838 if No (Body_Id) then
10839 if Is_Type (E) then
10841 ("missing full declaration for }", Parent (E), E);
10843 Error_Msg_NE ("missing body for &", Parent (E), E);
10846 -- Package body has no completion for a declaration that appears
10847 -- in the corresponding spec. Post error on the body, with a
10848 -- reference to the non-completed declaration.
10851 Error_Msg_Sloc := Sloc (E);
10853 if Is_Type (E) then
10854 Error_Msg_NE ("missing full declaration for }!", Body_Id, E);
10856 elsif Is_Overloadable (E)
10857 and then Current_Entity_In_Scope (E) /= E
10859 -- It may be that the completion is mistyped and appears as
10860 -- a distinct overloading of the entity.
10863 Candidate : constant Entity_Id :=
10864 Current_Entity_In_Scope (E);
10865 Decl : constant Node_Id :=
10866 Unit_Declaration_Node (Candidate);
10869 if Is_Overloadable (Candidate)
10870 and then Ekind (Candidate) = Ekind (E)
10871 and then Nkind (Decl) = N_Subprogram_Body
10872 and then Acts_As_Spec (Decl)
10874 Check_Type_Conformant (Candidate, E);
10890 Pack_Id : constant Entity_Id := Current_Scope;
10892 -- Start of processing for Check_Completion
10895 E := First_Entity (Pack_Id);
10896 while Present (E) loop
10897 if Is_Intrinsic_Subprogram (E) then
10900 -- The following situation requires special handling: a child unit
10901 -- that appears in the context clause of the body of its parent:
10903 -- procedure Parent.Child (...);
10905 -- with Parent.Child;
10906 -- package body Parent is
10908 -- Here Parent.Child appears as a local entity, but should not be
10909 -- flagged as requiring completion, because it is a compilation
10912 -- Ignore missing completion for a subprogram that does not come from
10913 -- source (including the _Call primitive operation of RAS types,
10914 -- which has to have the flag Comes_From_Source for other purposes):
10915 -- we assume that the expander will provide the missing completion.
10916 -- In case of previous errors, other expansion actions that provide
10917 -- bodies for null procedures with not be invoked, so inhibit message
10920 -- Note that E_Operator is not in the list that follows, because
10921 -- this kind is reserved for predefined operators, that are
10922 -- intrinsic and do not need completion.
10924 elsif Ekind_In (E, E_Function,
10926 E_Generic_Function,
10927 E_Generic_Procedure)
10929 if Has_Completion (E) then
10932 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
10935 elsif Is_Subprogram (E)
10936 and then (not Comes_From_Source (E)
10937 or else Chars (E) = Name_uCall)
10942 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
10946 elsif Nkind (Parent (E)) = N_Procedure_Specification
10947 and then Null_Present (Parent (E))
10948 and then Serious_Errors_Detected > 0
10956 elsif Is_Entry (E) then
10957 if not Has_Completion (E) and then
10958 (Ekind (Scope (E)) = E_Protected_Object
10959 or else Ekind (Scope (E)) = E_Protected_Type)
10964 elsif Is_Package_Or_Generic_Package (E) then
10965 if Unit_Requires_Body (E) then
10966 if not Has_Completion (E)
10967 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
10973 elsif not Is_Child_Unit (E) then
10974 May_Need_Implicit_Body (E);
10977 -- A formal incomplete type (Ada 2012) does not require a completion;
10978 -- other incomplete type declarations do.
10980 elsif Ekind (E) = E_Incomplete_Type
10981 and then No (Underlying_Type (E))
10982 and then not Is_Generic_Type (E)
10986 elsif Ekind_In (E, E_Task_Type, E_Protected_Type)
10987 and then not Has_Completion (E)
10991 -- A single task declared in the current scope is a constant, verify
10992 -- that the body of its anonymous type is in the same scope. If the
10993 -- task is defined elsewhere, this may be a renaming declaration for
10994 -- which no completion is needed.
10996 elsif Ekind (E) = E_Constant
10997 and then Ekind (Etype (E)) = E_Task_Type
10998 and then not Has_Completion (Etype (E))
10999 and then Scope (Etype (E)) = Current_Scope
11003 elsif Ekind (E) = E_Protected_Object
11004 and then not Has_Completion (Etype (E))
11008 elsif Ekind (E) = E_Record_Type then
11009 if Is_Tagged_Type (E) then
11010 Check_Abstract_Overriding (E);
11011 Check_Conventions (E);
11014 Check_Aliased_Component_Types (E);
11016 elsif Ekind (E) = E_Array_Type then
11017 Check_Aliased_Component_Types (E);
11023 end Check_Completion;
11025 ------------------------------------
11026 -- Check_CPP_Type_Has_No_Defaults --
11027 ------------------------------------
11029 procedure Check_CPP_Type_Has_No_Defaults (T : Entity_Id) is
11030 Tdef : constant Node_Id := Type_Definition (Declaration_Node (T));
11035 -- Obtain the component list
11037 if Nkind (Tdef) = N_Record_Definition then
11038 Clist := Component_List (Tdef);
11039 else pragma Assert (Nkind (Tdef) = N_Derived_Type_Definition);
11040 Clist := Component_List (Record_Extension_Part (Tdef));
11043 -- Check all components to ensure no default expressions
11045 if Present (Clist) then
11046 Comp := First (Component_Items (Clist));
11047 while Present (Comp) loop
11048 if Present (Expression (Comp)) then
11050 ("component of imported 'C'P'P type cannot have "
11051 & "default expression", Expression (Comp));
11057 end Check_CPP_Type_Has_No_Defaults;
11059 ----------------------------
11060 -- Check_Delta_Expression --
11061 ----------------------------
11063 procedure Check_Delta_Expression (E : Node_Id) is
11065 if not (Is_Real_Type (Etype (E))) then
11066 Wrong_Type (E, Any_Real);
11068 elsif not Is_OK_Static_Expression (E) then
11069 Flag_Non_Static_Expr
11070 ("non-static expression used for delta value!", E);
11072 elsif not UR_Is_Positive (Expr_Value_R (E)) then
11073 Error_Msg_N ("delta expression must be positive", E);
11079 -- If any of above errors occurred, then replace the incorrect
11080 -- expression by the real 0.1, which should prevent further errors.
11083 Make_Real_Literal (Sloc (E), Ureal_Tenth));
11084 Analyze_And_Resolve (E, Standard_Float);
11085 end Check_Delta_Expression;
11087 -----------------------------
11088 -- Check_Digits_Expression --
11089 -----------------------------
11091 procedure Check_Digits_Expression (E : Node_Id) is
11093 if not (Is_Integer_Type (Etype (E))) then
11094 Wrong_Type (E, Any_Integer);
11096 elsif not Is_OK_Static_Expression (E) then
11097 Flag_Non_Static_Expr
11098 ("non-static expression used for digits value!", E);
11100 elsif Expr_Value (E) <= 0 then
11101 Error_Msg_N ("digits value must be greater than zero", E);
11107 -- If any of above errors occurred, then replace the incorrect
11108 -- expression by the integer 1, which should prevent further errors.
11110 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
11111 Analyze_And_Resolve (E, Standard_Integer);
11113 end Check_Digits_Expression;
11115 --------------------------
11116 -- Check_Initialization --
11117 --------------------------
11119 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
11121 -- Special processing for limited types
11123 if Is_Limited_Type (T)
11124 and then not In_Instance
11125 and then not In_Inlined_Body
11127 if not OK_For_Limited_Init (T, Exp) then
11129 -- In GNAT mode, this is just a warning, to allow it to be evilly
11130 -- turned off. Otherwise it is a real error.
11134 ("??cannot initialize entities of limited type!", Exp);
11136 elsif Ada_Version < Ada_2005 then
11138 -- The side effect removal machinery may generate illegal Ada
11139 -- code to avoid the usage of access types and 'reference in
11140 -- SPARK mode. Since this is legal code with respect to theorem
11141 -- proving, do not emit the error.
11144 and then Nkind (Exp) = N_Function_Call
11145 and then Nkind (Parent (Exp)) = N_Object_Declaration
11146 and then not Comes_From_Source
11147 (Defining_Identifier (Parent (Exp)))
11153 ("cannot initialize entities of limited type", Exp);
11154 Explain_Limited_Type (T, Exp);
11158 -- Specialize error message according to kind of illegal
11159 -- initial expression.
11161 if Nkind (Exp) = N_Type_Conversion
11162 and then Nkind (Expression (Exp)) = N_Function_Call
11165 ("illegal context for call"
11166 & " to function with limited result", Exp);
11170 ("initialization of limited object requires aggregate "
11171 & "or function call", Exp);
11177 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag gets
11178 -- set unless we can be sure that no range check is required.
11180 if (GNATprove_Mode or not Expander_Active)
11181 and then Is_Scalar_Type (T)
11182 and then not Is_In_Range (Exp, T, Assume_Valid => True)
11184 Set_Do_Range_Check (Exp);
11186 end Check_Initialization;
11188 ----------------------
11189 -- Check_Interfaces --
11190 ----------------------
11192 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
11193 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
11196 Iface_Def : Node_Id;
11197 Iface_Typ : Entity_Id;
11198 Parent_Node : Node_Id;
11200 Is_Task : Boolean := False;
11201 -- Set True if parent type or any progenitor is a task interface
11203 Is_Protected : Boolean := False;
11204 -- Set True if parent type or any progenitor is a protected interface
11206 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
11207 -- Check that a progenitor is compatible with declaration. If an error
11208 -- message is output, it is posted on Error_Node.
11214 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
11215 Iface_Id : constant Entity_Id :=
11216 Defining_Identifier (Parent (Iface_Def));
11217 Type_Def : Node_Id;
11220 if Nkind (N) = N_Private_Extension_Declaration then
11223 Type_Def := Type_Definition (N);
11226 if Is_Task_Interface (Iface_Id) then
11229 elsif Is_Protected_Interface (Iface_Id) then
11230 Is_Protected := True;
11233 if Is_Synchronized_Interface (Iface_Id) then
11235 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
11236 -- extension derived from a synchronized interface must explicitly
11237 -- be declared synchronized, because the full view will be a
11238 -- synchronized type.
11240 if Nkind (N) = N_Private_Extension_Declaration then
11241 if not Synchronized_Present (N) then
11243 ("private extension of& must be explicitly synchronized",
11247 -- However, by 3.9.4(16/2), a full type that is a record extension
11248 -- is never allowed to derive from a synchronized interface (note
11249 -- that interfaces must be excluded from this check, because those
11250 -- are represented by derived type definitions in some cases).
11252 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11253 and then not Interface_Present (Type_Definition (N))
11255 Error_Msg_N ("record extension cannot derive from synchronized "
11256 & "interface", Error_Node);
11260 -- Check that the characteristics of the progenitor are compatible
11261 -- with the explicit qualifier in the declaration.
11262 -- The check only applies to qualifiers that come from source.
11263 -- Limited_Present also appears in the declaration of corresponding
11264 -- records, and the check does not apply to them.
11266 if Limited_Present (Type_Def)
11268 Is_Concurrent_Record_Type (Defining_Identifier (N))
11270 if Is_Limited_Interface (Parent_Type)
11271 and then not Is_Limited_Interface (Iface_Id)
11274 ("progenitor & must be limited interface",
11275 Error_Node, Iface_Id);
11278 (Task_Present (Iface_Def)
11279 or else Protected_Present (Iface_Def)
11280 or else Synchronized_Present (Iface_Def))
11281 and then Nkind (N) /= N_Private_Extension_Declaration
11282 and then not Error_Posted (N)
11285 ("progenitor & must be limited interface",
11286 Error_Node, Iface_Id);
11289 -- Protected interfaces can only inherit from limited, synchronized
11290 -- or protected interfaces.
11292 elsif Nkind (N) = N_Full_Type_Declaration
11293 and then Protected_Present (Type_Def)
11295 if Limited_Present (Iface_Def)
11296 or else Synchronized_Present (Iface_Def)
11297 or else Protected_Present (Iface_Def)
11301 elsif Task_Present (Iface_Def) then
11302 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11303 & "from task interface", Error_Node);
11306 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11307 & "from non-limited interface", Error_Node);
11310 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
11311 -- limited and synchronized.
11313 elsif Synchronized_Present (Type_Def) then
11314 if Limited_Present (Iface_Def)
11315 or else Synchronized_Present (Iface_Def)
11319 elsif Protected_Present (Iface_Def)
11320 and then Nkind (N) /= N_Private_Extension_Declaration
11322 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11323 & "from protected interface", Error_Node);
11325 elsif Task_Present (Iface_Def)
11326 and then Nkind (N) /= N_Private_Extension_Declaration
11328 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11329 & "from task interface", Error_Node);
11331 elsif not Is_Limited_Interface (Iface_Id) then
11332 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11333 & "from non-limited interface", Error_Node);
11336 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
11337 -- synchronized or task interfaces.
11339 elsif Nkind (N) = N_Full_Type_Declaration
11340 and then Task_Present (Type_Def)
11342 if Limited_Present (Iface_Def)
11343 or else Synchronized_Present (Iface_Def)
11344 or else Task_Present (Iface_Def)
11348 elsif Protected_Present (Iface_Def) then
11349 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11350 & "protected interface", Error_Node);
11353 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11354 & "non-limited interface", Error_Node);
11359 -- Start of processing for Check_Interfaces
11362 if Is_Interface (Parent_Type) then
11363 if Is_Task_Interface (Parent_Type) then
11366 elsif Is_Protected_Interface (Parent_Type) then
11367 Is_Protected := True;
11371 if Nkind (N) = N_Private_Extension_Declaration then
11373 -- Check that progenitors are compatible with declaration
11375 Iface := First (Interface_List (Def));
11376 while Present (Iface) loop
11377 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11379 Parent_Node := Parent (Base_Type (Iface_Typ));
11380 Iface_Def := Type_Definition (Parent_Node);
11382 if not Is_Interface (Iface_Typ) then
11383 Diagnose_Interface (Iface, Iface_Typ);
11385 Check_Ifaces (Iface_Def, Iface);
11391 if Is_Task and Is_Protected then
11393 ("type cannot derive from task and protected interface", N);
11399 -- Full type declaration of derived type.
11400 -- Check compatibility with parent if it is interface type
11402 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11403 and then Is_Interface (Parent_Type)
11405 Parent_Node := Parent (Parent_Type);
11407 -- More detailed checks for interface varieties
11410 (Iface_Def => Type_Definition (Parent_Node),
11411 Error_Node => Subtype_Indication (Type_Definition (N)));
11414 Iface := First (Interface_List (Def));
11415 while Present (Iface) loop
11416 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11418 Parent_Node := Parent (Base_Type (Iface_Typ));
11419 Iface_Def := Type_Definition (Parent_Node);
11421 if not Is_Interface (Iface_Typ) then
11422 Diagnose_Interface (Iface, Iface_Typ);
11425 -- "The declaration of a specific descendant of an interface
11426 -- type freezes the interface type" RM 13.14
11428 Freeze_Before (N, Iface_Typ);
11429 Check_Ifaces (Iface_Def, Error_Node => Iface);
11435 if Is_Task and Is_Protected then
11437 ("type cannot derive from task and protected interface", N);
11439 end Check_Interfaces;
11441 ------------------------------------
11442 -- Check_Or_Process_Discriminants --
11443 ------------------------------------
11445 -- If an incomplete or private type declaration was already given for the
11446 -- type, the discriminants may have already been processed if they were
11447 -- present on the incomplete declaration. In this case a full conformance
11448 -- check has been performed in Find_Type_Name, and we then recheck here
11449 -- some properties that can't be checked on the partial view alone.
11450 -- Otherwise we call Process_Discriminants.
11452 procedure Check_Or_Process_Discriminants
11455 Prev : Entity_Id := Empty)
11458 if Has_Discriminants (T) then
11460 -- Discriminants are already set on T if they were already present
11461 -- on the partial view. Make them visible to component declarations.
11465 -- Discriminant on T (full view) referencing expr on partial view
11467 Prev_D : Entity_Id;
11468 -- Entity of corresponding discriminant on partial view
11471 -- Discriminant specification for full view, expression is
11472 -- the syntactic copy on full view (which has been checked for
11473 -- conformance with partial view), only used here to post error
11477 D := First_Discriminant (T);
11478 New_D := First (Discriminant_Specifications (N));
11479 while Present (D) loop
11480 Prev_D := Current_Entity (D);
11481 Set_Current_Entity (D);
11482 Set_Is_Immediately_Visible (D);
11483 Set_Homonym (D, Prev_D);
11485 -- Handle the case where there is an untagged partial view and
11486 -- the full view is tagged: must disallow discriminants with
11487 -- defaults, unless compiling for Ada 2012, which allows a
11488 -- limited tagged type to have defaulted discriminants (see
11489 -- AI05-0214). However, suppress error here if it was already
11490 -- reported on the default expression of the partial view.
11492 if Is_Tagged_Type (T)
11493 and then Present (Expression (Parent (D)))
11494 and then (not Is_Limited_Type (Current_Scope)
11495 or else Ada_Version < Ada_2012)
11496 and then not Error_Posted (Expression (Parent (D)))
11498 if Ada_Version >= Ada_2012 then
11500 ("discriminants of nonlimited tagged type cannot have "
11502 Expression (New_D));
11505 ("discriminants of tagged type cannot have defaults",
11506 Expression (New_D));
11510 -- Ada 2005 (AI-230): Access discriminant allowed in
11511 -- non-limited record types.
11513 if Ada_Version < Ada_2005 then
11515 -- This restriction gets applied to the full type here. It
11516 -- has already been applied earlier to the partial view.
11518 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
11521 Next_Discriminant (D);
11526 elsif Present (Discriminant_Specifications (N)) then
11527 Process_Discriminants (N, Prev);
11529 end Check_Or_Process_Discriminants;
11531 ----------------------
11532 -- Check_Real_Bound --
11533 ----------------------
11535 procedure Check_Real_Bound (Bound : Node_Id) is
11537 if not Is_Real_Type (Etype (Bound)) then
11539 ("bound in real type definition must be of real type", Bound);
11541 elsif not Is_OK_Static_Expression (Bound) then
11542 Flag_Non_Static_Expr
11543 ("non-static expression used for real type bound!", Bound);
11550 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
11552 Resolve (Bound, Standard_Float);
11553 end Check_Real_Bound;
11555 ------------------------------
11556 -- Complete_Private_Subtype --
11557 ------------------------------
11559 procedure Complete_Private_Subtype
11562 Full_Base : Entity_Id;
11563 Related_Nod : Node_Id)
11565 Save_Next_Entity : Entity_Id;
11566 Save_Homonym : Entity_Id;
11569 -- Set semantic attributes for (implicit) private subtype completion.
11570 -- If the full type has no discriminants, then it is a copy of the
11571 -- full view of the base. Otherwise, it is a subtype of the base with
11572 -- a possible discriminant constraint. Save and restore the original
11573 -- Next_Entity field of full to ensure that the calls to Copy_Node do
11574 -- not corrupt the entity chain.
11576 -- Note that the type of the full view is the same entity as the type
11577 -- of the partial view. In this fashion, the subtype has access to the
11578 -- correct view of the parent.
11580 Save_Next_Entity := Next_Entity (Full);
11581 Save_Homonym := Homonym (Priv);
11583 case Ekind (Full_Base) is
11584 when E_Record_Type |
11590 Copy_Node (Priv, Full);
11592 Set_Has_Discriminants
11593 (Full, Has_Discriminants (Full_Base));
11594 Set_Has_Unknown_Discriminants
11595 (Full, Has_Unknown_Discriminants (Full_Base));
11596 Set_First_Entity (Full, First_Entity (Full_Base));
11597 Set_Last_Entity (Full, Last_Entity (Full_Base));
11599 -- If the underlying base type is constrained, we know that the
11600 -- full view of the subtype is constrained as well (the converse
11601 -- is not necessarily true).
11603 if Is_Constrained (Full_Base) then
11604 Set_Is_Constrained (Full);
11608 Copy_Node (Full_Base, Full);
11610 Set_Chars (Full, Chars (Priv));
11611 Conditional_Delay (Full, Priv);
11612 Set_Sloc (Full, Sloc (Priv));
11615 Set_Next_Entity (Full, Save_Next_Entity);
11616 Set_Homonym (Full, Save_Homonym);
11617 Set_Associated_Node_For_Itype (Full, Related_Nod);
11619 -- Set common attributes for all subtypes: kind, convention, etc.
11621 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
11622 Set_Convention (Full, Convention (Full_Base));
11624 -- The Etype of the full view is inconsistent. Gigi needs to see the
11625 -- structural full view, which is what the current scheme gives: the
11626 -- Etype of the full view is the etype of the full base. However, if the
11627 -- full base is a derived type, the full view then looks like a subtype
11628 -- of the parent, not a subtype of the full base. If instead we write:
11630 -- Set_Etype (Full, Full_Base);
11632 -- then we get inconsistencies in the front-end (confusion between
11633 -- views). Several outstanding bugs are related to this ???
11635 Set_Is_First_Subtype (Full, False);
11636 Set_Scope (Full, Scope (Priv));
11637 Set_Size_Info (Full, Full_Base);
11638 Set_RM_Size (Full, RM_Size (Full_Base));
11639 Set_Is_Itype (Full);
11641 -- A subtype of a private-type-without-discriminants, whose full-view
11642 -- has discriminants with default expressions, is not constrained.
11644 if not Has_Discriminants (Priv) then
11645 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
11647 if Has_Discriminants (Full_Base) then
11648 Set_Discriminant_Constraint
11649 (Full, Discriminant_Constraint (Full_Base));
11651 -- The partial view may have been indefinite, the full view
11654 Set_Has_Unknown_Discriminants
11655 (Full, Has_Unknown_Discriminants (Full_Base));
11659 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
11660 Set_Depends_On_Private (Full, Has_Private_Component (Full));
11662 -- Freeze the private subtype entity if its parent is delayed, and not
11663 -- already frozen. We skip this processing if the type is an anonymous
11664 -- subtype of a record component, or is the corresponding record of a
11665 -- protected type, since these are processed when the enclosing type
11668 if not Is_Type (Scope (Full)) then
11669 Set_Has_Delayed_Freeze (Full,
11670 Has_Delayed_Freeze (Full_Base)
11671 and then (not Is_Frozen (Full_Base)));
11674 Set_Freeze_Node (Full, Empty);
11675 Set_Is_Frozen (Full, False);
11676 Set_Full_View (Priv, Full);
11678 if Has_Discriminants (Full) then
11679 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
11680 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
11682 if Has_Unknown_Discriminants (Full) then
11683 Set_Discriminant_Constraint (Full, No_Elist);
11687 if Ekind (Full_Base) = E_Record_Type
11688 and then Has_Discriminants (Full_Base)
11689 and then Has_Discriminants (Priv) -- might not, if errors
11690 and then not Has_Unknown_Discriminants (Priv)
11691 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
11693 Create_Constrained_Components
11694 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
11696 -- If the full base is itself derived from private, build a congruent
11697 -- subtype of its underlying type, for use by the back end. For a
11698 -- constrained record component, the declaration cannot be placed on
11699 -- the component list, but it must nevertheless be built an analyzed, to
11700 -- supply enough information for Gigi to compute the size of component.
11702 elsif Ekind (Full_Base) in Private_Kind
11703 and then Is_Derived_Type (Full_Base)
11704 and then Has_Discriminants (Full_Base)
11705 and then (Ekind (Current_Scope) /= E_Record_Subtype)
11707 if not Is_Itype (Priv)
11709 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
11711 Build_Underlying_Full_View
11712 (Parent (Priv), Full, Etype (Full_Base));
11714 elsif Nkind (Related_Nod) = N_Component_Declaration then
11715 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
11718 elsif Is_Record_Type (Full_Base) then
11720 -- Show Full is simply a renaming of Full_Base
11722 Set_Cloned_Subtype (Full, Full_Base);
11725 -- It is unsafe to share the bounds of a scalar type, because the Itype
11726 -- is elaborated on demand, and if a bound is non-static then different
11727 -- orders of elaboration in different units will lead to different
11728 -- external symbols.
11730 if Is_Scalar_Type (Full_Base) then
11731 Set_Scalar_Range (Full,
11732 Make_Range (Sloc (Related_Nod),
11734 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
11736 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
11738 -- This completion inherits the bounds of the full parent, but if
11739 -- the parent is an unconstrained floating point type, so is the
11742 if Is_Floating_Point_Type (Full_Base) then
11743 Set_Includes_Infinities
11744 (Scalar_Range (Full), Has_Infinities (Full_Base));
11748 -- ??? It seems that a lot of fields are missing that should be copied
11749 -- from Full_Base to Full. Here are some that are introduced in a
11750 -- non-disruptive way but a cleanup is necessary.
11752 if Is_Tagged_Type (Full_Base) then
11753 Set_Is_Tagged_Type (Full);
11754 Set_Direct_Primitive_Operations
11755 (Full, Direct_Primitive_Operations (Full_Base));
11756 Set_No_Tagged_Streams_Pragma
11757 (Full, No_Tagged_Streams_Pragma (Full_Base));
11759 -- Inherit class_wide type of full_base in case the partial view was
11760 -- not tagged. Otherwise it has already been created when the private
11761 -- subtype was analyzed.
11763 if No (Class_Wide_Type (Full)) then
11764 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
11767 -- If this is a subtype of a protected or task type, constrain its
11768 -- corresponding record, unless this is a subtype without constraints,
11769 -- i.e. a simple renaming as with an actual subtype in an instance.
11771 elsif Is_Concurrent_Type (Full_Base) then
11772 if Has_Discriminants (Full)
11773 and then Present (Corresponding_Record_Type (Full_Base))
11775 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
11777 Set_Corresponding_Record_Type (Full,
11778 Constrain_Corresponding_Record
11779 (Full, Corresponding_Record_Type (Full_Base), Related_Nod));
11782 Set_Corresponding_Record_Type (Full,
11783 Corresponding_Record_Type (Full_Base));
11787 -- Link rep item chain, and also setting of Has_Predicates from private
11788 -- subtype to full subtype, since we will need these on the full subtype
11789 -- to create the predicate function. Note that the full subtype may
11790 -- already have rep items, inherited from the full view of the base
11791 -- type, so we must be sure not to overwrite these entries.
11796 Next_Item : Node_Id;
11799 Item := First_Rep_Item (Full);
11801 -- If no existing rep items on full type, we can just link directly
11802 -- to the list of items on the private type, if any exist.. Same if
11803 -- the rep items are only those inherited from the base
11806 or else Nkind (Item) /= N_Aspect_Specification
11807 or else Entity (Item) = Full_Base)
11808 and then Present (First_Rep_Item (Priv))
11810 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
11812 -- Otherwise, search to the end of items currently linked to the full
11813 -- subtype and append the private items to the end. However, if Priv
11814 -- and Full already have the same list of rep items, then the append
11815 -- is not done, as that would create a circularity.
11817 elsif Item /= First_Rep_Item (Priv) then
11820 Next_Item := Next_Rep_Item (Item);
11821 exit when No (Next_Item);
11824 -- If the private view has aspect specifications, the full view
11825 -- inherits them. Since these aspects may already have been
11826 -- attached to the full view during derivation, do not append
11827 -- them if already present.
11829 if Item = First_Rep_Item (Priv) then
11835 -- And link the private type items at the end of the chain
11838 Set_Next_Rep_Item (Item, First_Rep_Item (Priv));
11843 -- Make sure Has_Predicates is set on full type if it is set on the
11844 -- private type. Note that it may already be set on the full type and
11845 -- if so, we don't want to unset it. Similarly, propagate information
11846 -- about delayed aspects, because the corresponding pragmas must be
11847 -- analyzed when one of the views is frozen. This last step is needed
11848 -- in particular when the full type is a scalar type for which an
11849 -- anonymous base type is constructed.
11851 if Has_Predicates (Priv) then
11852 Set_Has_Predicates (Full);
11855 if Has_Delayed_Aspects (Priv) then
11856 Set_Has_Delayed_Aspects (Full);
11858 end Complete_Private_Subtype;
11860 ----------------------------
11861 -- Constant_Redeclaration --
11862 ----------------------------
11864 procedure Constant_Redeclaration
11869 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
11870 Obj_Def : constant Node_Id := Object_Definition (N);
11873 procedure Check_Possible_Deferred_Completion
11874 (Prev_Id : Entity_Id;
11875 Prev_Obj_Def : Node_Id;
11876 Curr_Obj_Def : Node_Id);
11877 -- Determine whether the two object definitions describe the partial
11878 -- and the full view of a constrained deferred constant. Generate
11879 -- a subtype for the full view and verify that it statically matches
11880 -- the subtype of the partial view.
11882 procedure Check_Recursive_Declaration (Typ : Entity_Id);
11883 -- If deferred constant is an access type initialized with an allocator,
11884 -- check whether there is an illegal recursion in the definition,
11885 -- through a default value of some record subcomponent. This is normally
11886 -- detected when generating init procs, but requires this additional
11887 -- mechanism when expansion is disabled.
11889 ----------------------------------------
11890 -- Check_Possible_Deferred_Completion --
11891 ----------------------------------------
11893 procedure Check_Possible_Deferred_Completion
11894 (Prev_Id : Entity_Id;
11895 Prev_Obj_Def : Node_Id;
11896 Curr_Obj_Def : Node_Id)
11899 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
11900 and then Present (Constraint (Prev_Obj_Def))
11901 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
11902 and then Present (Constraint (Curr_Obj_Def))
11905 Loc : constant Source_Ptr := Sloc (N);
11906 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'S');
11907 Decl : constant Node_Id :=
11908 Make_Subtype_Declaration (Loc,
11909 Defining_Identifier => Def_Id,
11910 Subtype_Indication =>
11911 Relocate_Node (Curr_Obj_Def));
11914 Insert_Before_And_Analyze (N, Decl);
11915 Set_Etype (Id, Def_Id);
11917 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
11918 Error_Msg_Sloc := Sloc (Prev_Id);
11919 Error_Msg_N ("subtype does not statically match deferred "
11920 & "declaration #", N);
11924 end Check_Possible_Deferred_Completion;
11926 ---------------------------------
11927 -- Check_Recursive_Declaration --
11928 ---------------------------------
11930 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
11934 if Is_Record_Type (Typ) then
11935 Comp := First_Component (Typ);
11936 while Present (Comp) loop
11937 if Comes_From_Source (Comp) then
11938 if Present (Expression (Parent (Comp)))
11939 and then Is_Entity_Name (Expression (Parent (Comp)))
11940 and then Entity (Expression (Parent (Comp))) = Prev
11942 Error_Msg_Sloc := Sloc (Parent (Comp));
11944 ("illegal circularity with declaration for & #",
11948 elsif Is_Record_Type (Etype (Comp)) then
11949 Check_Recursive_Declaration (Etype (Comp));
11953 Next_Component (Comp);
11956 end Check_Recursive_Declaration;
11958 -- Start of processing for Constant_Redeclaration
11961 if Nkind (Parent (Prev)) = N_Object_Declaration then
11962 if Nkind (Object_Definition
11963 (Parent (Prev))) = N_Subtype_Indication
11965 -- Find type of new declaration. The constraints of the two
11966 -- views must match statically, but there is no point in
11967 -- creating an itype for the full view.
11969 if Nkind (Obj_Def) = N_Subtype_Indication then
11970 Find_Type (Subtype_Mark (Obj_Def));
11971 New_T := Entity (Subtype_Mark (Obj_Def));
11974 Find_Type (Obj_Def);
11975 New_T := Entity (Obj_Def);
11981 -- The full view may impose a constraint, even if the partial
11982 -- view does not, so construct the subtype.
11984 New_T := Find_Type_Of_Object (Obj_Def, N);
11989 -- Current declaration is illegal, diagnosed below in Enter_Name
11995 -- If previous full declaration or a renaming declaration exists, or if
11996 -- a homograph is present, let Enter_Name handle it, either with an
11997 -- error or with the removal of an overridden implicit subprogram.
11998 -- The previous one is a full declaration if it has an expression
11999 -- (which in the case of an aggregate is indicated by the Init flag).
12001 if Ekind (Prev) /= E_Constant
12002 or else Nkind (Parent (Prev)) = N_Object_Renaming_Declaration
12003 or else Present (Expression (Parent (Prev)))
12004 or else Has_Init_Expression (Parent (Prev))
12005 or else Present (Full_View (Prev))
12009 -- Verify that types of both declarations match, or else that both types
12010 -- are anonymous access types whose designated subtypes statically match
12011 -- (as allowed in Ada 2005 by AI-385).
12013 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
12015 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
12016 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
12017 or else Is_Access_Constant (Etype (New_T)) /=
12018 Is_Access_Constant (Etype (Prev))
12019 or else Can_Never_Be_Null (Etype (New_T)) /=
12020 Can_Never_Be_Null (Etype (Prev))
12021 or else Null_Exclusion_Present (Parent (Prev)) /=
12022 Null_Exclusion_Present (Parent (Id))
12023 or else not Subtypes_Statically_Match
12024 (Designated_Type (Etype (Prev)),
12025 Designated_Type (Etype (New_T))))
12027 Error_Msg_Sloc := Sloc (Prev);
12028 Error_Msg_N ("type does not match declaration#", N);
12029 Set_Full_View (Prev, Id);
12030 Set_Etype (Id, Any_Type);
12032 -- A deferred constant whose type is an anonymous array is always
12033 -- illegal (unless imported). A detailed error message might be
12034 -- helpful for Ada beginners.
12036 if Nkind (Object_Definition (Parent (Prev)))
12037 = N_Constrained_Array_Definition
12038 and then Nkind (Object_Definition (N))
12039 = N_Constrained_Array_Definition
12041 Error_Msg_N ("\each anonymous array is a distinct type", N);
12042 Error_Msg_N ("a deferred constant must have a named type",
12043 Object_Definition (Parent (Prev)));
12047 Null_Exclusion_Present (Parent (Prev))
12048 and then not Null_Exclusion_Present (N)
12050 Error_Msg_Sloc := Sloc (Prev);
12051 Error_Msg_N ("null-exclusion does not match declaration#", N);
12052 Set_Full_View (Prev, Id);
12053 Set_Etype (Id, Any_Type);
12055 -- If so, process the full constant declaration
12058 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
12059 -- the deferred declaration is constrained, then the subtype defined
12060 -- by the subtype_indication in the full declaration shall match it
12063 Check_Possible_Deferred_Completion
12065 Prev_Obj_Def => Object_Definition (Parent (Prev)),
12066 Curr_Obj_Def => Obj_Def);
12068 Set_Full_View (Prev, Id);
12069 Set_Is_Public (Id, Is_Public (Prev));
12070 Set_Is_Internal (Id);
12071 Append_Entity (Id, Current_Scope);
12073 -- Check ALIASED present if present before (RM 7.4(7))
12075 if Is_Aliased (Prev)
12076 and then not Aliased_Present (N)
12078 Error_Msg_Sloc := Sloc (Prev);
12079 Error_Msg_N ("ALIASED required (see declaration #)", N);
12082 -- Check that placement is in private part and that the incomplete
12083 -- declaration appeared in the visible part.
12085 if Ekind (Current_Scope) = E_Package
12086 and then not In_Private_Part (Current_Scope)
12088 Error_Msg_Sloc := Sloc (Prev);
12090 ("full constant for declaration # must be in private part", N);
12092 elsif Ekind (Current_Scope) = E_Package
12094 List_Containing (Parent (Prev)) /=
12095 Visible_Declarations (Package_Specification (Current_Scope))
12098 ("deferred constant must be declared in visible part",
12102 if Is_Access_Type (T)
12103 and then Nkind (Expression (N)) = N_Allocator
12105 Check_Recursive_Declaration (Designated_Type (T));
12108 -- A deferred constant is a visible entity. If type has invariants,
12109 -- verify that the initial value satisfies them.
12111 if Has_Invariants (T) and then Present (Invariant_Procedure (T)) then
12113 Make_Invariant_Call (New_Occurrence_Of (Prev, Sloc (N))));
12116 end Constant_Redeclaration;
12118 ----------------------
12119 -- Constrain_Access --
12120 ----------------------
12122 procedure Constrain_Access
12123 (Def_Id : in out Entity_Id;
12125 Related_Nod : Node_Id)
12127 T : constant Entity_Id := Entity (Subtype_Mark (S));
12128 Desig_Type : constant Entity_Id := Designated_Type (T);
12129 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
12130 Constraint_OK : Boolean := True;
12133 if Is_Array_Type (Desig_Type) then
12134 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
12136 elsif (Is_Record_Type (Desig_Type)
12137 or else Is_Incomplete_Or_Private_Type (Desig_Type))
12138 and then not Is_Constrained (Desig_Type)
12140 -- ??? The following code is a temporary bypass to ignore a
12141 -- discriminant constraint on access type if it is constraining
12142 -- the current record. Avoid creating the implicit subtype of the
12143 -- record we are currently compiling since right now, we cannot
12144 -- handle these. For now, just return the access type itself.
12146 if Desig_Type = Current_Scope
12147 and then No (Def_Id)
12149 Set_Ekind (Desig_Subtype, E_Record_Subtype);
12150 Def_Id := Entity (Subtype_Mark (S));
12152 -- This call added to ensure that the constraint is analyzed
12153 -- (needed for a B test). Note that we still return early from
12154 -- this procedure to avoid recursive processing. ???
12156 Constrain_Discriminated_Type
12157 (Desig_Subtype, S, Related_Nod, For_Access => True);
12161 -- Enforce rule that the constraint is illegal if there is an
12162 -- unconstrained view of the designated type. This means that the
12163 -- partial view (either a private type declaration or a derivation
12164 -- from a private type) has no discriminants. (Defect Report
12165 -- 8652/0008, Technical Corrigendum 1, checked by ACATS B371001).
12167 -- Rule updated for Ada 2005: The private type is said to have
12168 -- a constrained partial view, given that objects of the type
12169 -- can be declared. Furthermore, the rule applies to all access
12170 -- types, unlike the rule concerning default discriminants (see
12173 if (Ekind (T) = E_General_Access_Type or else Ada_Version >= Ada_2005)
12174 and then Has_Private_Declaration (Desig_Type)
12175 and then In_Open_Scopes (Scope (Desig_Type))
12176 and then Has_Discriminants (Desig_Type)
12179 Pack : constant Node_Id :=
12180 Unit_Declaration_Node (Scope (Desig_Type));
12185 if Nkind (Pack) = N_Package_Declaration then
12186 Decls := Visible_Declarations (Specification (Pack));
12187 Decl := First (Decls);
12188 while Present (Decl) loop
12189 if (Nkind (Decl) = N_Private_Type_Declaration
12190 and then Chars (Defining_Identifier (Decl)) =
12191 Chars (Desig_Type))
12194 (Nkind (Decl) = N_Full_Type_Declaration
12196 Chars (Defining_Identifier (Decl)) =
12198 and then Is_Derived_Type (Desig_Type)
12200 Has_Private_Declaration (Etype (Desig_Type)))
12202 if No (Discriminant_Specifications (Decl)) then
12204 ("cannot constrain access type if designated "
12205 & "type has constrained partial view", S);
12217 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
12218 For_Access => True);
12220 elsif Is_Concurrent_Type (Desig_Type)
12221 and then not Is_Constrained (Desig_Type)
12223 Constrain_Concurrent (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
12226 Error_Msg_N ("invalid constraint on access type", S);
12228 -- We simply ignore an invalid constraint
12230 Desig_Subtype := Desig_Type;
12231 Constraint_OK := False;
12234 if No (Def_Id) then
12235 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
12237 Set_Ekind (Def_Id, E_Access_Subtype);
12240 if Constraint_OK then
12241 Set_Etype (Def_Id, Base_Type (T));
12243 if Is_Private_Type (Desig_Type) then
12244 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
12247 Set_Etype (Def_Id, Any_Type);
12250 Set_Size_Info (Def_Id, T);
12251 Set_Is_Constrained (Def_Id, Constraint_OK);
12252 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
12253 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12254 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
12256 Conditional_Delay (Def_Id, T);
12258 -- AI-363 : Subtypes of general access types whose designated types have
12259 -- default discriminants are disallowed. In instances, the rule has to
12260 -- be checked against the actual, of which T is the subtype. In a
12261 -- generic body, the rule is checked assuming that the actual type has
12262 -- defaulted discriminants.
12264 if Ada_Version >= Ada_2005 or else Warn_On_Ada_2005_Compatibility then
12265 if Ekind (Base_Type (T)) = E_General_Access_Type
12266 and then Has_Defaulted_Discriminants (Desig_Type)
12268 if Ada_Version < Ada_2005 then
12270 ("access subtype of general access type would not " &
12271 "be allowed in Ada 2005?y?", S);
12274 ("access subtype of general access type not allowed", S);
12277 Error_Msg_N ("\discriminants have defaults", S);
12279 elsif Is_Access_Type (T)
12280 and then Is_Generic_Type (Desig_Type)
12281 and then Has_Discriminants (Desig_Type)
12282 and then In_Package_Body (Current_Scope)
12284 if Ada_Version < Ada_2005 then
12286 ("access subtype would not be allowed in generic body "
12287 & "in Ada 2005?y?", S);
12290 ("access subtype not allowed in generic body", S);
12294 ("\designated type is a discriminated formal", S);
12297 end Constrain_Access;
12299 ---------------------
12300 -- Constrain_Array --
12301 ---------------------
12303 procedure Constrain_Array
12304 (Def_Id : in out Entity_Id;
12306 Related_Nod : Node_Id;
12307 Related_Id : Entity_Id;
12308 Suffix : Character)
12310 C : constant Node_Id := Constraint (SI);
12311 Number_Of_Constraints : Nat := 0;
12314 Constraint_OK : Boolean := True;
12317 T := Entity (Subtype_Mark (SI));
12319 if Is_Access_Type (T) then
12320 T := Designated_Type (T);
12323 -- If an index constraint follows a subtype mark in a subtype indication
12324 -- then the type or subtype denoted by the subtype mark must not already
12325 -- impose an index constraint. The subtype mark must denote either an
12326 -- unconstrained array type or an access type whose designated type
12327 -- is such an array type... (RM 3.6.1)
12329 if Is_Constrained (T) then
12330 Error_Msg_N ("array type is already constrained", Subtype_Mark (SI));
12331 Constraint_OK := False;
12334 S := First (Constraints (C));
12335 while Present (S) loop
12336 Number_Of_Constraints := Number_Of_Constraints + 1;
12340 -- In either case, the index constraint must provide a discrete
12341 -- range for each index of the array type and the type of each
12342 -- discrete range must be the same as that of the corresponding
12343 -- index. (RM 3.6.1)
12345 if Number_Of_Constraints /= Number_Dimensions (T) then
12346 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
12347 Constraint_OK := False;
12350 S := First (Constraints (C));
12351 Index := First_Index (T);
12354 -- Apply constraints to each index type
12356 for J in 1 .. Number_Of_Constraints loop
12357 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
12365 if No (Def_Id) then
12367 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
12368 Set_Parent (Def_Id, Related_Nod);
12371 Set_Ekind (Def_Id, E_Array_Subtype);
12374 Set_Size_Info (Def_Id, (T));
12375 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12376 Set_Etype (Def_Id, Base_Type (T));
12378 if Constraint_OK then
12379 Set_First_Index (Def_Id, First (Constraints (C)));
12381 Set_First_Index (Def_Id, First_Index (T));
12384 Set_Is_Constrained (Def_Id, True);
12385 Set_Is_Aliased (Def_Id, Is_Aliased (T));
12386 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12388 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
12389 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
12391 -- A subtype does not inherit the Packed_Array_Impl_Type of is parent.
12392 -- We need to initialize the attribute because if Def_Id is previously
12393 -- analyzed through a limited_with clause, it will have the attributes
12394 -- of an incomplete type, one of which is an Elist that overlaps the
12395 -- Packed_Array_Impl_Type field.
12397 Set_Packed_Array_Impl_Type (Def_Id, Empty);
12399 -- Build a freeze node if parent still needs one. Also make sure that
12400 -- the Depends_On_Private status is set because the subtype will need
12401 -- reprocessing at the time the base type does, and also we must set a
12402 -- conditional delay.
12404 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
12405 Conditional_Delay (Def_Id, T);
12406 end Constrain_Array;
12408 ------------------------------
12409 -- Constrain_Component_Type --
12410 ------------------------------
12412 function Constrain_Component_Type
12414 Constrained_Typ : Entity_Id;
12415 Related_Node : Node_Id;
12417 Constraints : Elist_Id) return Entity_Id
12419 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
12420 Compon_Type : constant Entity_Id := Etype (Comp);
12422 function Build_Constrained_Array_Type
12423 (Old_Type : Entity_Id) return Entity_Id;
12424 -- If Old_Type is an array type, one of whose indexes is constrained
12425 -- by a discriminant, build an Itype whose constraint replaces the
12426 -- discriminant with its value in the constraint.
12428 function Build_Constrained_Discriminated_Type
12429 (Old_Type : Entity_Id) return Entity_Id;
12430 -- Ditto for record components
12432 function Build_Constrained_Access_Type
12433 (Old_Type : Entity_Id) return Entity_Id;
12434 -- Ditto for access types. Makes use of previous two functions, to
12435 -- constrain designated type.
12437 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
12438 -- T is an array or discriminated type, C is a list of constraints
12439 -- that apply to T. This routine builds the constrained subtype.
12441 function Is_Discriminant (Expr : Node_Id) return Boolean;
12442 -- Returns True if Expr is a discriminant
12444 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
12445 -- Find the value of discriminant Discrim in Constraint
12447 -----------------------------------
12448 -- Build_Constrained_Access_Type --
12449 -----------------------------------
12451 function Build_Constrained_Access_Type
12452 (Old_Type : Entity_Id) return Entity_Id
12454 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
12456 Desig_Subtype : Entity_Id;
12460 -- if the original access type was not embedded in the enclosing
12461 -- type definition, there is no need to produce a new access
12462 -- subtype. In fact every access type with an explicit constraint
12463 -- generates an itype whose scope is the enclosing record.
12465 if not Is_Type (Scope (Old_Type)) then
12468 elsif Is_Array_Type (Desig_Type) then
12469 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
12471 elsif Has_Discriminants (Desig_Type) then
12473 -- This may be an access type to an enclosing record type for
12474 -- which we are constructing the constrained components. Return
12475 -- the enclosing record subtype. This is not always correct,
12476 -- but avoids infinite recursion. ???
12478 Desig_Subtype := Any_Type;
12480 for J in reverse 0 .. Scope_Stack.Last loop
12481 Scop := Scope_Stack.Table (J).Entity;
12484 and then Base_Type (Scop) = Base_Type (Desig_Type)
12486 Desig_Subtype := Scop;
12489 exit when not Is_Type (Scop);
12492 if Desig_Subtype = Any_Type then
12494 Build_Constrained_Discriminated_Type (Desig_Type);
12501 if Desig_Subtype /= Desig_Type then
12503 -- The Related_Node better be here or else we won't be able
12504 -- to attach new itypes to a node in the tree.
12506 pragma Assert (Present (Related_Node));
12508 Itype := Create_Itype (E_Access_Subtype, Related_Node);
12510 Set_Etype (Itype, Base_Type (Old_Type));
12511 Set_Size_Info (Itype, (Old_Type));
12512 Set_Directly_Designated_Type (Itype, Desig_Subtype);
12513 Set_Depends_On_Private (Itype, Has_Private_Component
12515 Set_Is_Access_Constant (Itype, Is_Access_Constant
12518 -- The new itype needs freezing when it depends on a not frozen
12519 -- type and the enclosing subtype needs freezing.
12521 if Has_Delayed_Freeze (Constrained_Typ)
12522 and then not Is_Frozen (Constrained_Typ)
12524 Conditional_Delay (Itype, Base_Type (Old_Type));
12532 end Build_Constrained_Access_Type;
12534 ----------------------------------
12535 -- Build_Constrained_Array_Type --
12536 ----------------------------------
12538 function Build_Constrained_Array_Type
12539 (Old_Type : Entity_Id) return Entity_Id
12543 Old_Index : Node_Id;
12544 Range_Node : Node_Id;
12545 Constr_List : List_Id;
12547 Need_To_Create_Itype : Boolean := False;
12550 Old_Index := First_Index (Old_Type);
12551 while Present (Old_Index) loop
12552 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
12554 if Is_Discriminant (Lo_Expr)
12556 Is_Discriminant (Hi_Expr)
12558 Need_To_Create_Itype := True;
12561 Next_Index (Old_Index);
12564 if Need_To_Create_Itype then
12565 Constr_List := New_List;
12567 Old_Index := First_Index (Old_Type);
12568 while Present (Old_Index) loop
12569 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
12571 if Is_Discriminant (Lo_Expr) then
12572 Lo_Expr := Get_Discr_Value (Lo_Expr);
12575 if Is_Discriminant (Hi_Expr) then
12576 Hi_Expr := Get_Discr_Value (Hi_Expr);
12581 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
12583 Append (Range_Node, To => Constr_List);
12585 Next_Index (Old_Index);
12588 return Build_Subtype (Old_Type, Constr_List);
12593 end Build_Constrained_Array_Type;
12595 ------------------------------------------
12596 -- Build_Constrained_Discriminated_Type --
12597 ------------------------------------------
12599 function Build_Constrained_Discriminated_Type
12600 (Old_Type : Entity_Id) return Entity_Id
12603 Constr_List : List_Id;
12604 Old_Constraint : Elmt_Id;
12606 Need_To_Create_Itype : Boolean := False;
12609 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
12610 while Present (Old_Constraint) loop
12611 Expr := Node (Old_Constraint);
12613 if Is_Discriminant (Expr) then
12614 Need_To_Create_Itype := True;
12617 Next_Elmt (Old_Constraint);
12620 if Need_To_Create_Itype then
12621 Constr_List := New_List;
12623 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
12624 while Present (Old_Constraint) loop
12625 Expr := Node (Old_Constraint);
12627 if Is_Discriminant (Expr) then
12628 Expr := Get_Discr_Value (Expr);
12631 Append (New_Copy_Tree (Expr), To => Constr_List);
12633 Next_Elmt (Old_Constraint);
12636 return Build_Subtype (Old_Type, Constr_List);
12641 end Build_Constrained_Discriminated_Type;
12643 -------------------
12644 -- Build_Subtype --
12645 -------------------
12647 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
12649 Subtyp_Decl : Node_Id;
12650 Def_Id : Entity_Id;
12651 Btyp : Entity_Id := Base_Type (T);
12654 -- The Related_Node better be here or else we won't be able to
12655 -- attach new itypes to a node in the tree.
12657 pragma Assert (Present (Related_Node));
12659 -- If the view of the component's type is incomplete or private
12660 -- with unknown discriminants, then the constraint must be applied
12661 -- to the full type.
12663 if Has_Unknown_Discriminants (Btyp)
12664 and then Present (Underlying_Type (Btyp))
12666 Btyp := Underlying_Type (Btyp);
12670 Make_Subtype_Indication (Loc,
12671 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
12672 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
12674 Def_Id := Create_Itype (Ekind (T), Related_Node);
12677 Make_Subtype_Declaration (Loc,
12678 Defining_Identifier => Def_Id,
12679 Subtype_Indication => Indic);
12681 Set_Parent (Subtyp_Decl, Parent (Related_Node));
12683 -- Itypes must be analyzed with checks off (see package Itypes)
12685 Analyze (Subtyp_Decl, Suppress => All_Checks);
12690 ---------------------
12691 -- Get_Discr_Value --
12692 ---------------------
12694 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
12699 -- The discriminant may be declared for the type, in which case we
12700 -- find it by iterating over the list of discriminants. If the
12701 -- discriminant is inherited from a parent type, it appears as the
12702 -- corresponding discriminant of the current type. This will be the
12703 -- case when constraining an inherited component whose constraint is
12704 -- given by a discriminant of the parent.
12706 D := First_Discriminant (Typ);
12707 E := First_Elmt (Constraints);
12709 while Present (D) loop
12710 if D = Entity (Discrim)
12711 or else D = CR_Discriminant (Entity (Discrim))
12712 or else Corresponding_Discriminant (D) = Entity (Discrim)
12717 Next_Discriminant (D);
12721 -- The Corresponding_Discriminant mechanism is incomplete, because
12722 -- the correspondence between new and old discriminants is not one
12723 -- to one: one new discriminant can constrain several old ones. In
12724 -- that case, scan sequentially the stored_constraint, the list of
12725 -- discriminants of the parents, and the constraints.
12727 -- Previous code checked for the present of the Stored_Constraint
12728 -- list for the derived type, but did not use it at all. Should it
12729 -- be present when the component is a discriminated task type?
12731 if Is_Derived_Type (Typ)
12732 and then Scope (Entity (Discrim)) = Etype (Typ)
12734 D := First_Discriminant (Etype (Typ));
12735 E := First_Elmt (Constraints);
12736 while Present (D) loop
12737 if D = Entity (Discrim) then
12741 Next_Discriminant (D);
12746 -- Something is wrong if we did not find the value
12748 raise Program_Error;
12749 end Get_Discr_Value;
12751 ---------------------
12752 -- Is_Discriminant --
12753 ---------------------
12755 function Is_Discriminant (Expr : Node_Id) return Boolean is
12756 Discrim_Scope : Entity_Id;
12759 if Denotes_Discriminant (Expr) then
12760 Discrim_Scope := Scope (Entity (Expr));
12762 -- Either we have a reference to one of Typ's discriminants,
12764 pragma Assert (Discrim_Scope = Typ
12766 -- or to the discriminants of the parent type, in the case
12767 -- of a derivation of a tagged type with variants.
12769 or else Discrim_Scope = Etype (Typ)
12770 or else Full_View (Discrim_Scope) = Etype (Typ)
12772 -- or same as above for the case where the discriminants
12773 -- were declared in Typ's private view.
12775 or else (Is_Private_Type (Discrim_Scope)
12776 and then Chars (Discrim_Scope) = Chars (Typ))
12778 -- or else we are deriving from the full view and the
12779 -- discriminant is declared in the private entity.
12781 or else (Is_Private_Type (Typ)
12782 and then Chars (Discrim_Scope) = Chars (Typ))
12784 -- Or we are constrained the corresponding record of a
12785 -- synchronized type that completes a private declaration.
12787 or else (Is_Concurrent_Record_Type (Typ)
12789 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
12791 -- or we have a class-wide type, in which case make sure the
12792 -- discriminant found belongs to the root type.
12794 or else (Is_Class_Wide_Type (Typ)
12795 and then Etype (Typ) = Discrim_Scope));
12800 -- In all other cases we have something wrong
12803 end Is_Discriminant;
12805 -- Start of processing for Constrain_Component_Type
12808 if Nkind (Parent (Comp)) = N_Component_Declaration
12809 and then Comes_From_Source (Parent (Comp))
12810 and then Comes_From_Source
12811 (Subtype_Indication (Component_Definition (Parent (Comp))))
12814 (Subtype_Indication (Component_Definition (Parent (Comp))))
12816 return Compon_Type;
12818 elsif Is_Array_Type (Compon_Type) then
12819 return Build_Constrained_Array_Type (Compon_Type);
12821 elsif Has_Discriminants (Compon_Type) then
12822 return Build_Constrained_Discriminated_Type (Compon_Type);
12824 elsif Is_Access_Type (Compon_Type) then
12825 return Build_Constrained_Access_Type (Compon_Type);
12828 return Compon_Type;
12830 end Constrain_Component_Type;
12832 --------------------------
12833 -- Constrain_Concurrent --
12834 --------------------------
12836 -- For concurrent types, the associated record value type carries the same
12837 -- discriminants, so when we constrain a concurrent type, we must constrain
12838 -- the corresponding record type as well.
12840 procedure Constrain_Concurrent
12841 (Def_Id : in out Entity_Id;
12843 Related_Nod : Node_Id;
12844 Related_Id : Entity_Id;
12845 Suffix : Character)
12847 -- Retrieve Base_Type to ensure getting to the concurrent type in the
12848 -- case of a private subtype (needed when only doing semantic analysis).
12850 T_Ent : Entity_Id := Base_Type (Entity (Subtype_Mark (SI)));
12854 if Is_Access_Type (T_Ent) then
12855 T_Ent := Designated_Type (T_Ent);
12858 T_Val := Corresponding_Record_Type (T_Ent);
12860 if Present (T_Val) then
12862 if No (Def_Id) then
12863 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
12865 -- Elaborate itype now, as it may be used in a subsequent
12866 -- synchronized operation in another scope.
12868 if Nkind (Related_Nod) = N_Full_Type_Declaration then
12869 Build_Itype_Reference (Def_Id, Related_Nod);
12873 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
12875 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12876 Set_Corresponding_Record_Type (Def_Id,
12877 Constrain_Corresponding_Record (Def_Id, T_Val, Related_Nod));
12880 -- If there is no associated record, expansion is disabled and this
12881 -- is a generic context. Create a subtype in any case, so that
12882 -- semantic analysis can proceed.
12884 if No (Def_Id) then
12885 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
12888 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
12890 end Constrain_Concurrent;
12892 ------------------------------------
12893 -- Constrain_Corresponding_Record --
12894 ------------------------------------
12896 function Constrain_Corresponding_Record
12897 (Prot_Subt : Entity_Id;
12898 Corr_Rec : Entity_Id;
12899 Related_Nod : Node_Id) return Entity_Id
12901 T_Sub : constant Entity_Id :=
12902 Create_Itype (E_Record_Subtype, Related_Nod, Corr_Rec, 'C');
12905 Set_Etype (T_Sub, Corr_Rec);
12906 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
12907 Set_Is_Constrained (T_Sub, True);
12908 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
12909 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
12911 if Has_Discriminants (Prot_Subt) then -- False only if errors.
12912 Set_Discriminant_Constraint
12913 (T_Sub, Discriminant_Constraint (Prot_Subt));
12914 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
12915 Create_Constrained_Components
12916 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
12919 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
12921 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
12922 Conditional_Delay (T_Sub, Corr_Rec);
12925 -- This is a component subtype: it will be frozen in the context of
12926 -- the enclosing record's init_proc, so that discriminant references
12927 -- are resolved to discriminals. (Note: we used to skip freezing
12928 -- altogether in that case, which caused errors downstream for
12929 -- components of a bit packed array type).
12931 Set_Has_Delayed_Freeze (T_Sub);
12935 end Constrain_Corresponding_Record;
12937 -----------------------
12938 -- Constrain_Decimal --
12939 -----------------------
12941 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
12942 T : constant Entity_Id := Entity (Subtype_Mark (S));
12943 C : constant Node_Id := Constraint (S);
12944 Loc : constant Source_Ptr := Sloc (C);
12945 Range_Expr : Node_Id;
12946 Digits_Expr : Node_Id;
12951 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
12953 if Nkind (C) = N_Range_Constraint then
12954 Range_Expr := Range_Expression (C);
12955 Digits_Val := Digits_Value (T);
12958 pragma Assert (Nkind (C) = N_Digits_Constraint);
12960 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
12962 Digits_Expr := Digits_Expression (C);
12963 Analyze_And_Resolve (Digits_Expr, Any_Integer);
12965 Check_Digits_Expression (Digits_Expr);
12966 Digits_Val := Expr_Value (Digits_Expr);
12968 if Digits_Val > Digits_Value (T) then
12970 ("digits expression is incompatible with subtype", C);
12971 Digits_Val := Digits_Value (T);
12974 if Present (Range_Constraint (C)) then
12975 Range_Expr := Range_Expression (Range_Constraint (C));
12977 Range_Expr := Empty;
12981 Set_Etype (Def_Id, Base_Type (T));
12982 Set_Size_Info (Def_Id, (T));
12983 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12984 Set_Delta_Value (Def_Id, Delta_Value (T));
12985 Set_Scale_Value (Def_Id, Scale_Value (T));
12986 Set_Small_Value (Def_Id, Small_Value (T));
12987 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
12988 Set_Digits_Value (Def_Id, Digits_Val);
12990 -- Manufacture range from given digits value if no range present
12992 if No (Range_Expr) then
12993 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
12997 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
12999 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
13002 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
13003 Set_Discrete_RM_Size (Def_Id);
13005 -- Unconditionally delay the freeze, since we cannot set size
13006 -- information in all cases correctly until the freeze point.
13008 Set_Has_Delayed_Freeze (Def_Id);
13009 end Constrain_Decimal;
13011 ----------------------------------
13012 -- Constrain_Discriminated_Type --
13013 ----------------------------------
13015 procedure Constrain_Discriminated_Type
13016 (Def_Id : Entity_Id;
13018 Related_Nod : Node_Id;
13019 For_Access : Boolean := False)
13021 E : constant Entity_Id := Entity (Subtype_Mark (S));
13024 Elist : Elist_Id := New_Elmt_List;
13026 procedure Fixup_Bad_Constraint;
13027 -- This is called after finding a bad constraint, and after having
13028 -- posted an appropriate error message. The mission is to leave the
13029 -- entity T in as reasonable state as possible.
13031 --------------------------
13032 -- Fixup_Bad_Constraint --
13033 --------------------------
13035 procedure Fixup_Bad_Constraint is
13037 -- Set a reasonable Ekind for the entity. For an incomplete type,
13038 -- we can't do much, but for other types, we can set the proper
13039 -- corresponding subtype kind.
13041 if Ekind (T) = E_Incomplete_Type then
13042 Set_Ekind (Def_Id, Ekind (T));
13044 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
13047 -- Set Etype to the known type, to reduce chances of cascaded errors
13049 Set_Etype (Def_Id, E);
13050 Set_Error_Posted (Def_Id);
13051 end Fixup_Bad_Constraint;
13053 -- Start of processing for Constrain_Discriminated_Type
13056 C := Constraint (S);
13058 -- A discriminant constraint is only allowed in a subtype indication,
13059 -- after a subtype mark. This subtype mark must denote either a type
13060 -- with discriminants, or an access type whose designated type is a
13061 -- type with discriminants. A discriminant constraint specifies the
13062 -- values of these discriminants (RM 3.7.2(5)).
13064 T := Base_Type (Entity (Subtype_Mark (S)));
13066 if Is_Access_Type (T) then
13067 T := Designated_Type (T);
13070 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal.
13071 -- Avoid generating an error for access-to-incomplete subtypes.
13073 if Ada_Version >= Ada_2005
13074 and then Ekind (T) = E_Incomplete_Type
13075 and then Nkind (Parent (S)) = N_Subtype_Declaration
13076 and then not Is_Itype (Def_Id)
13078 -- A little sanity check, emit an error message if the type
13079 -- has discriminants to begin with. Type T may be a regular
13080 -- incomplete type or imported via a limited with clause.
13082 if Has_Discriminants (T)
13083 or else (From_Limited_With (T)
13084 and then Present (Non_Limited_View (T))
13085 and then Nkind (Parent (Non_Limited_View (T))) =
13086 N_Full_Type_Declaration
13087 and then Present (Discriminant_Specifications
13088 (Parent (Non_Limited_View (T)))))
13091 ("(Ada 2005) incomplete subtype may not be constrained", C);
13093 Error_Msg_N ("invalid constraint: type has no discriminant", C);
13096 Fixup_Bad_Constraint;
13099 -- Check that the type has visible discriminants. The type may be
13100 -- a private type with unknown discriminants whose full view has
13101 -- discriminants which are invisible.
13103 elsif not Has_Discriminants (T)
13105 (Has_Unknown_Discriminants (T)
13106 and then Is_Private_Type (T))
13108 Error_Msg_N ("invalid constraint: type has no discriminant", C);
13109 Fixup_Bad_Constraint;
13112 elsif Is_Constrained (E)
13113 or else (Ekind (E) = E_Class_Wide_Subtype
13114 and then Present (Discriminant_Constraint (E)))
13116 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
13117 Fixup_Bad_Constraint;
13121 -- T may be an unconstrained subtype (e.g. a generic actual).
13122 -- Constraint applies to the base type.
13124 T := Base_Type (T);
13126 Elist := Build_Discriminant_Constraints (T, S);
13128 -- If the list returned was empty we had an error in building the
13129 -- discriminant constraint. We have also already signalled an error
13130 -- in the incomplete type case
13132 if Is_Empty_Elmt_List (Elist) then
13133 Fixup_Bad_Constraint;
13137 Build_Discriminated_Subtype (T, Def_Id, Elist, Related_Nod, For_Access);
13138 end Constrain_Discriminated_Type;
13140 ---------------------------
13141 -- Constrain_Enumeration --
13142 ---------------------------
13144 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
13145 T : constant Entity_Id := Entity (Subtype_Mark (S));
13146 C : constant Node_Id := Constraint (S);
13149 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13151 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
13153 Set_Etype (Def_Id, Base_Type (T));
13154 Set_Size_Info (Def_Id, (T));
13155 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13156 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13158 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13160 Set_Discrete_RM_Size (Def_Id);
13161 end Constrain_Enumeration;
13163 ----------------------
13164 -- Constrain_Float --
13165 ----------------------
13167 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
13168 T : constant Entity_Id := Entity (Subtype_Mark (S));
13174 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
13176 Set_Etype (Def_Id, Base_Type (T));
13177 Set_Size_Info (Def_Id, (T));
13178 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13180 -- Process the constraint
13182 C := Constraint (S);
13184 -- Digits constraint present
13186 if Nkind (C) = N_Digits_Constraint then
13188 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
13189 Check_Restriction (No_Obsolescent_Features, C);
13191 if Warn_On_Obsolescent_Feature then
13193 ("subtype digits constraint is an " &
13194 "obsolescent feature (RM J.3(8))?j?", C);
13197 D := Digits_Expression (C);
13198 Analyze_And_Resolve (D, Any_Integer);
13199 Check_Digits_Expression (D);
13200 Set_Digits_Value (Def_Id, Expr_Value (D));
13202 -- Check that digits value is in range. Obviously we can do this
13203 -- at compile time, but it is strictly a runtime check, and of
13204 -- course there is an ACVC test that checks this.
13206 if Digits_Value (Def_Id) > Digits_Value (T) then
13207 Error_Msg_Uint_1 := Digits_Value (T);
13208 Error_Msg_N ("??digits value is too large, maximum is ^", D);
13210 Make_Raise_Constraint_Error (Sloc (D),
13211 Reason => CE_Range_Check_Failed);
13212 Insert_Action (Declaration_Node (Def_Id), Rais);
13215 C := Range_Constraint (C);
13217 -- No digits constraint present
13220 Set_Digits_Value (Def_Id, Digits_Value (T));
13223 -- Range constraint present
13225 if Nkind (C) = N_Range_Constraint then
13226 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13228 -- No range constraint present
13231 pragma Assert (No (C));
13232 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13235 Set_Is_Constrained (Def_Id);
13236 end Constrain_Float;
13238 ---------------------
13239 -- Constrain_Index --
13240 ---------------------
13242 procedure Constrain_Index
13245 Related_Nod : Node_Id;
13246 Related_Id : Entity_Id;
13247 Suffix : Character;
13248 Suffix_Index : Nat)
13250 Def_Id : Entity_Id;
13251 R : Node_Id := Empty;
13252 T : constant Entity_Id := Etype (Index);
13256 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
13257 Set_Etype (Def_Id, Base_Type (T));
13259 if Nkind (S) = N_Range
13261 (Nkind (S) = N_Attribute_Reference
13262 and then Attribute_Name (S) = Name_Range)
13264 -- A Range attribute will be transformed into N_Range by Resolve
13270 Process_Range_Expr_In_Decl (R, T);
13272 if not Error_Posted (S)
13274 (Nkind (S) /= N_Range
13275 or else not Covers (T, (Etype (Low_Bound (S))))
13276 or else not Covers (T, (Etype (High_Bound (S)))))
13278 if Base_Type (T) /= Any_Type
13279 and then Etype (Low_Bound (S)) /= Any_Type
13280 and then Etype (High_Bound (S)) /= Any_Type
13282 Error_Msg_N ("range expected", S);
13286 elsif Nkind (S) = N_Subtype_Indication then
13288 -- The parser has verified that this is a discrete indication
13290 Resolve_Discrete_Subtype_Indication (S, T);
13291 Bad_Predicated_Subtype_Use
13292 ("subtype& has predicate, not allowed in index constraint",
13293 S, Entity (Subtype_Mark (S)));
13295 R := Range_Expression (Constraint (S));
13297 -- Capture values of bounds and generate temporaries for them if
13298 -- needed, since checks may cause duplication of the expressions
13299 -- which must not be reevaluated.
13301 -- The forced evaluation removes side effects from expressions, which
13302 -- should occur also in GNATprove mode. Otherwise, we end up with
13303 -- unexpected insertions of actions at places where this is not
13304 -- supposed to occur, e.g. on default parameters of a call.
13306 if Expander_Active or GNATprove_Mode then
13308 (Low_Bound (R), Related_Id => Def_Id, Is_Low_Bound => True);
13310 (High_Bound (R), Related_Id => Def_Id, Is_High_Bound => True);
13313 elsif Nkind (S) = N_Discriminant_Association then
13315 -- Syntactically valid in subtype indication
13317 Error_Msg_N ("invalid index constraint", S);
13318 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13321 -- Subtype_Mark case, no anonymous subtypes to construct
13326 if Is_Entity_Name (S) then
13327 if not Is_Type (Entity (S)) then
13328 Error_Msg_N ("expect subtype mark for index constraint", S);
13330 elsif Base_Type (Entity (S)) /= Base_Type (T) then
13331 Wrong_Type (S, Base_Type (T));
13333 -- Check error of subtype with predicate in index constraint
13336 Bad_Predicated_Subtype_Use
13337 ("subtype& has predicate, not allowed in index constraint",
13344 Error_Msg_N ("invalid index constraint", S);
13345 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13350 -- Complete construction of the Itype
13352 if Is_Modular_Integer_Type (T) then
13353 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13355 elsif Is_Integer_Type (T) then
13356 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13359 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13360 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13361 Set_First_Literal (Def_Id, First_Literal (T));
13364 Set_Size_Info (Def_Id, (T));
13365 Set_RM_Size (Def_Id, RM_Size (T));
13366 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13368 Set_Scalar_Range (Def_Id, R);
13370 Set_Etype (S, Def_Id);
13371 Set_Discrete_RM_Size (Def_Id);
13372 end Constrain_Index;
13374 -----------------------
13375 -- Constrain_Integer --
13376 -----------------------
13378 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
13379 T : constant Entity_Id := Entity (Subtype_Mark (S));
13380 C : constant Node_Id := Constraint (S);
13383 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13385 if Is_Modular_Integer_Type (T) then
13386 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13388 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13391 Set_Etype (Def_Id, Base_Type (T));
13392 Set_Size_Info (Def_Id, (T));
13393 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13394 Set_Discrete_RM_Size (Def_Id);
13395 end Constrain_Integer;
13397 ------------------------------
13398 -- Constrain_Ordinary_Fixed --
13399 ------------------------------
13401 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
13402 T : constant Entity_Id := Entity (Subtype_Mark (S));
13408 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
13409 Set_Etype (Def_Id, Base_Type (T));
13410 Set_Size_Info (Def_Id, (T));
13411 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13412 Set_Small_Value (Def_Id, Small_Value (T));
13414 -- Process the constraint
13416 C := Constraint (S);
13418 -- Delta constraint present
13420 if Nkind (C) = N_Delta_Constraint then
13422 Check_SPARK_05_Restriction ("delta constraint is not allowed", S);
13423 Check_Restriction (No_Obsolescent_Features, C);
13425 if Warn_On_Obsolescent_Feature then
13427 ("subtype delta constraint is an " &
13428 "obsolescent feature (RM J.3(7))?j?");
13431 D := Delta_Expression (C);
13432 Analyze_And_Resolve (D, Any_Real);
13433 Check_Delta_Expression (D);
13434 Set_Delta_Value (Def_Id, Expr_Value_R (D));
13436 -- Check that delta value is in range. Obviously we can do this
13437 -- at compile time, but it is strictly a runtime check, and of
13438 -- course there is an ACVC test that checks this.
13440 if Delta_Value (Def_Id) < Delta_Value (T) then
13441 Error_Msg_N ("??delta value is too small", D);
13443 Make_Raise_Constraint_Error (Sloc (D),
13444 Reason => CE_Range_Check_Failed);
13445 Insert_Action (Declaration_Node (Def_Id), Rais);
13448 C := Range_Constraint (C);
13450 -- No delta constraint present
13453 Set_Delta_Value (Def_Id, Delta_Value (T));
13456 -- Range constraint present
13458 if Nkind (C) = N_Range_Constraint then
13459 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13461 -- No range constraint present
13464 pragma Assert (No (C));
13465 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13468 Set_Discrete_RM_Size (Def_Id);
13470 -- Unconditionally delay the freeze, since we cannot set size
13471 -- information in all cases correctly until the freeze point.
13473 Set_Has_Delayed_Freeze (Def_Id);
13474 end Constrain_Ordinary_Fixed;
13476 -----------------------
13477 -- Contain_Interface --
13478 -----------------------
13480 function Contain_Interface
13481 (Iface : Entity_Id;
13482 Ifaces : Elist_Id) return Boolean
13484 Iface_Elmt : Elmt_Id;
13487 if Present (Ifaces) then
13488 Iface_Elmt := First_Elmt (Ifaces);
13489 while Present (Iface_Elmt) loop
13490 if Node (Iface_Elmt) = Iface then
13494 Next_Elmt (Iface_Elmt);
13499 end Contain_Interface;
13501 ---------------------------
13502 -- Convert_Scalar_Bounds --
13503 ---------------------------
13505 procedure Convert_Scalar_Bounds
13507 Parent_Type : Entity_Id;
13508 Derived_Type : Entity_Id;
13511 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
13518 -- Defend against previous errors
13520 if No (Scalar_Range (Derived_Type)) then
13521 Check_Error_Detected;
13525 Lo := Build_Scalar_Bound
13526 (Type_Low_Bound (Derived_Type),
13527 Parent_Type, Implicit_Base);
13529 Hi := Build_Scalar_Bound
13530 (Type_High_Bound (Derived_Type),
13531 Parent_Type, Implicit_Base);
13538 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
13540 Set_Parent (Rng, N);
13541 Set_Scalar_Range (Derived_Type, Rng);
13543 -- Analyze the bounds
13545 Analyze_And_Resolve (Lo, Implicit_Base);
13546 Analyze_And_Resolve (Hi, Implicit_Base);
13548 -- Analyze the range itself, except that we do not analyze it if
13549 -- the bounds are real literals, and we have a fixed-point type.
13550 -- The reason for this is that we delay setting the bounds in this
13551 -- case till we know the final Small and Size values (see circuit
13552 -- in Freeze.Freeze_Fixed_Point_Type for further details).
13554 if Is_Fixed_Point_Type (Parent_Type)
13555 and then Nkind (Lo) = N_Real_Literal
13556 and then Nkind (Hi) = N_Real_Literal
13560 -- Here we do the analysis of the range
13562 -- Note: we do this manually, since if we do a normal Analyze and
13563 -- Resolve call, there are problems with the conversions used for
13564 -- the derived type range.
13567 Set_Etype (Rng, Implicit_Base);
13568 Set_Analyzed (Rng, True);
13570 end Convert_Scalar_Bounds;
13572 -------------------
13573 -- Copy_And_Swap --
13574 -------------------
13576 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
13578 -- Initialize new full declaration entity by copying the pertinent
13579 -- fields of the corresponding private declaration entity.
13581 -- We temporarily set Ekind to a value appropriate for a type to
13582 -- avoid assert failures in Einfo from checking for setting type
13583 -- attributes on something that is not a type. Ekind (Priv) is an
13584 -- appropriate choice, since it allowed the attributes to be set
13585 -- in the first place. This Ekind value will be modified later.
13587 Set_Ekind (Full, Ekind (Priv));
13589 -- Also set Etype temporarily to Any_Type, again, in the absence
13590 -- of errors, it will be properly reset, and if there are errors,
13591 -- then we want a value of Any_Type to remain.
13593 Set_Etype (Full, Any_Type);
13595 -- Now start copying attributes
13597 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
13599 if Has_Discriminants (Full) then
13600 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
13601 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
13604 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
13605 Set_Homonym (Full, Homonym (Priv));
13606 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
13607 Set_Is_Public (Full, Is_Public (Priv));
13608 Set_Is_Pure (Full, Is_Pure (Priv));
13609 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
13610 Set_Has_Pragma_Unmodified (Full, Has_Pragma_Unmodified (Priv));
13611 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
13612 Set_Has_Pragma_Unreferenced_Objects
13613 (Full, Has_Pragma_Unreferenced_Objects
13616 Conditional_Delay (Full, Priv);
13618 if Is_Tagged_Type (Full) then
13619 Set_Direct_Primitive_Operations
13620 (Full, Direct_Primitive_Operations (Priv));
13621 Set_No_Tagged_Streams_Pragma
13622 (Full, No_Tagged_Streams_Pragma (Priv));
13624 if Is_Base_Type (Priv) then
13625 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
13629 Set_Is_Volatile (Full, Is_Volatile (Priv));
13630 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
13631 Set_Scope (Full, Scope (Priv));
13632 Set_Next_Entity (Full, Next_Entity (Priv));
13633 Set_First_Entity (Full, First_Entity (Priv));
13634 Set_Last_Entity (Full, Last_Entity (Priv));
13636 -- If access types have been recorded for later handling, keep them in
13637 -- the full view so that they get handled when the full view freeze
13638 -- node is expanded.
13640 if Present (Freeze_Node (Priv))
13641 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
13643 Ensure_Freeze_Node (Full);
13644 Set_Access_Types_To_Process
13645 (Freeze_Node (Full),
13646 Access_Types_To_Process (Freeze_Node (Priv)));
13649 -- Swap the two entities. Now Private is the full type entity and Full
13650 -- is the private one. They will be swapped back at the end of the
13651 -- private part. This swapping ensures that the entity that is visible
13652 -- in the private part is the full declaration.
13654 Exchange_Entities (Priv, Full);
13655 Append_Entity (Full, Scope (Full));
13658 -------------------------------------
13659 -- Copy_Array_Base_Type_Attributes --
13660 -------------------------------------
13662 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
13664 Set_Component_Alignment (T1, Component_Alignment (T2));
13665 Set_Component_Type (T1, Component_Type (T2));
13666 Set_Component_Size (T1, Component_Size (T2));
13667 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
13668 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
13669 Set_Has_Protected (T1, Has_Protected (T2));
13670 Set_Has_Task (T1, Has_Task (T2));
13671 Set_Is_Packed (T1, Is_Packed (T2));
13672 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
13673 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
13674 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
13675 end Copy_Array_Base_Type_Attributes;
13677 -----------------------------------
13678 -- Copy_Array_Subtype_Attributes --
13679 -----------------------------------
13681 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
13683 Set_Size_Info (T1, T2);
13685 Set_First_Index (T1, First_Index (T2));
13686 Set_Is_Aliased (T1, Is_Aliased (T2));
13687 Set_Is_Volatile (T1, Is_Volatile (T2));
13688 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
13689 Set_Is_Constrained (T1, Is_Constrained (T2));
13690 Set_Depends_On_Private (T1, Has_Private_Component (T2));
13691 Inherit_Rep_Item_Chain (T1, T2);
13692 Set_Convention (T1, Convention (T2));
13693 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
13694 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
13695 Set_Packed_Array_Impl_Type (T1, Packed_Array_Impl_Type (T2));
13696 end Copy_Array_Subtype_Attributes;
13698 -----------------------------------
13699 -- Create_Constrained_Components --
13700 -----------------------------------
13702 procedure Create_Constrained_Components
13704 Decl_Node : Node_Id;
13706 Constraints : Elist_Id)
13708 Loc : constant Source_Ptr := Sloc (Subt);
13709 Comp_List : constant Elist_Id := New_Elmt_List;
13710 Parent_Type : constant Entity_Id := Etype (Typ);
13711 Assoc_List : constant List_Id := New_List;
13712 Discr_Val : Elmt_Id;
13716 Is_Static : Boolean := True;
13718 procedure Collect_Fixed_Components (Typ : Entity_Id);
13719 -- Collect parent type components that do not appear in a variant part
13721 procedure Create_All_Components;
13722 -- Iterate over Comp_List to create the components of the subtype
13724 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
13725 -- Creates a new component from Old_Compon, copying all the fields from
13726 -- it, including its Etype, inserts the new component in the Subt entity
13727 -- chain and returns the new component.
13729 function Is_Variant_Record (T : Entity_Id) return Boolean;
13730 -- If true, and discriminants are static, collect only components from
13731 -- variants selected by discriminant values.
13733 ------------------------------
13734 -- Collect_Fixed_Components --
13735 ------------------------------
13737 procedure Collect_Fixed_Components (Typ : Entity_Id) is
13739 -- Build association list for discriminants, and find components of the
13740 -- variant part selected by the values of the discriminants.
13742 Old_C := First_Discriminant (Typ);
13743 Discr_Val := First_Elmt (Constraints);
13744 while Present (Old_C) loop
13745 Append_To (Assoc_List,
13746 Make_Component_Association (Loc,
13747 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
13748 Expression => New_Copy (Node (Discr_Val))));
13750 Next_Elmt (Discr_Val);
13751 Next_Discriminant (Old_C);
13754 -- The tag and the possible parent component are unconditionally in
13757 if Is_Tagged_Type (Typ) or else Has_Controlled_Component (Typ) then
13758 Old_C := First_Component (Typ);
13759 while Present (Old_C) loop
13760 if Nam_In (Chars (Old_C), Name_uTag, Name_uParent) then
13761 Append_Elmt (Old_C, Comp_List);
13764 Next_Component (Old_C);
13767 end Collect_Fixed_Components;
13769 ---------------------------
13770 -- Create_All_Components --
13771 ---------------------------
13773 procedure Create_All_Components is
13777 Comp := First_Elmt (Comp_List);
13778 while Present (Comp) loop
13779 Old_C := Node (Comp);
13780 New_C := Create_Component (Old_C);
13784 Constrain_Component_Type
13785 (Old_C, Subt, Decl_Node, Typ, Constraints));
13786 Set_Is_Public (New_C, Is_Public (Subt));
13790 end Create_All_Components;
13792 ----------------------
13793 -- Create_Component --
13794 ----------------------
13796 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
13797 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
13800 if Ekind (Old_Compon) = E_Discriminant
13801 and then Is_Completely_Hidden (Old_Compon)
13803 -- This is a shadow discriminant created for a discriminant of
13804 -- the parent type, which needs to be present in the subtype.
13805 -- Give the shadow discriminant an internal name that cannot
13806 -- conflict with that of visible components.
13808 Set_Chars (New_Compon, New_Internal_Name ('C'));
13811 -- Set the parent so we have a proper link for freezing etc. This is
13812 -- not a real parent pointer, since of course our parent does not own
13813 -- up to us and reference us, we are an illegitimate child of the
13814 -- original parent.
13816 Set_Parent (New_Compon, Parent (Old_Compon));
13818 -- If the old component's Esize was already determined and is a
13819 -- static value, then the new component simply inherits it. Otherwise
13820 -- the old component's size may require run-time determination, but
13821 -- the new component's size still might be statically determinable
13822 -- (if, for example it has a static constraint). In that case we want
13823 -- Layout_Type to recompute the component's size, so we reset its
13824 -- size and positional fields.
13826 if Frontend_Layout_On_Target
13827 and then not Known_Static_Esize (Old_Compon)
13829 Set_Esize (New_Compon, Uint_0);
13830 Init_Normalized_First_Bit (New_Compon);
13831 Init_Normalized_Position (New_Compon);
13832 Init_Normalized_Position_Max (New_Compon);
13835 -- We do not want this node marked as Comes_From_Source, since
13836 -- otherwise it would get first class status and a separate cross-
13837 -- reference line would be generated. Illegitimate children do not
13838 -- rate such recognition.
13840 Set_Comes_From_Source (New_Compon, False);
13842 -- But it is a real entity, and a birth certificate must be properly
13843 -- registered by entering it into the entity list.
13845 Enter_Name (New_Compon);
13848 end Create_Component;
13850 -----------------------
13851 -- Is_Variant_Record --
13852 -----------------------
13854 function Is_Variant_Record (T : Entity_Id) return Boolean is
13856 return Nkind (Parent (T)) = N_Full_Type_Declaration
13857 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
13858 and then Present (Component_List (Type_Definition (Parent (T))))
13861 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
13862 end Is_Variant_Record;
13864 -- Start of processing for Create_Constrained_Components
13867 pragma Assert (Subt /= Base_Type (Subt));
13868 pragma Assert (Typ = Base_Type (Typ));
13870 Set_First_Entity (Subt, Empty);
13871 Set_Last_Entity (Subt, Empty);
13873 -- Check whether constraint is fully static, in which case we can
13874 -- optimize the list of components.
13876 Discr_Val := First_Elmt (Constraints);
13877 while Present (Discr_Val) loop
13878 if not Is_OK_Static_Expression (Node (Discr_Val)) then
13879 Is_Static := False;
13883 Next_Elmt (Discr_Val);
13886 Set_Has_Static_Discriminants (Subt, Is_Static);
13890 -- Inherit the discriminants of the parent type
13892 Add_Discriminants : declare
13898 Old_C := First_Discriminant (Typ);
13900 while Present (Old_C) loop
13901 Num_Disc := Num_Disc + 1;
13902 New_C := Create_Component (Old_C);
13903 Set_Is_Public (New_C, Is_Public (Subt));
13904 Next_Discriminant (Old_C);
13907 -- For an untagged derived subtype, the number of discriminants may
13908 -- be smaller than the number of inherited discriminants, because
13909 -- several of them may be renamed by a single new discriminant or
13910 -- constrained. In this case, add the hidden discriminants back into
13911 -- the subtype, because they need to be present if the optimizer of
13912 -- the GCC 4.x back-end decides to break apart assignments between
13913 -- objects using the parent view into member-wise assignments.
13917 if Is_Derived_Type (Typ)
13918 and then not Is_Tagged_Type (Typ)
13920 Old_C := First_Stored_Discriminant (Typ);
13922 while Present (Old_C) loop
13923 Num_Gird := Num_Gird + 1;
13924 Next_Stored_Discriminant (Old_C);
13928 if Num_Gird > Num_Disc then
13930 -- Find out multiple uses of new discriminants, and add hidden
13931 -- components for the extra renamed discriminants. We recognize
13932 -- multiple uses through the Corresponding_Discriminant of a
13933 -- new discriminant: if it constrains several old discriminants,
13934 -- this field points to the last one in the parent type. The
13935 -- stored discriminants of the derived type have the same name
13936 -- as those of the parent.
13940 New_Discr : Entity_Id;
13941 Old_Discr : Entity_Id;
13944 Constr := First_Elmt (Stored_Constraint (Typ));
13945 Old_Discr := First_Stored_Discriminant (Typ);
13946 while Present (Constr) loop
13947 if Is_Entity_Name (Node (Constr))
13948 and then Ekind (Entity (Node (Constr))) = E_Discriminant
13950 New_Discr := Entity (Node (Constr));
13952 if Chars (Corresponding_Discriminant (New_Discr)) /=
13955 -- The new discriminant has been used to rename a
13956 -- subsequent old discriminant. Introduce a shadow
13957 -- component for the current old discriminant.
13959 New_C := Create_Component (Old_Discr);
13960 Set_Original_Record_Component (New_C, Old_Discr);
13964 -- The constraint has eliminated the old discriminant.
13965 -- Introduce a shadow component.
13967 New_C := Create_Component (Old_Discr);
13968 Set_Original_Record_Component (New_C, Old_Discr);
13971 Next_Elmt (Constr);
13972 Next_Stored_Discriminant (Old_Discr);
13976 end Add_Discriminants;
13979 and then Is_Variant_Record (Typ)
13981 Collect_Fixed_Components (Typ);
13983 Gather_Components (
13985 Component_List (Type_Definition (Parent (Typ))),
13986 Governed_By => Assoc_List,
13988 Report_Errors => Errors);
13989 pragma Assert (not Errors);
13991 Create_All_Components;
13993 -- If the subtype declaration is created for a tagged type derivation
13994 -- with constraints, we retrieve the record definition of the parent
13995 -- type to select the components of the proper variant.
13998 and then Is_Tagged_Type (Typ)
13999 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
14001 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
14002 and then Is_Variant_Record (Parent_Type)
14004 Collect_Fixed_Components (Typ);
14008 Component_List (Type_Definition (Parent (Parent_Type))),
14009 Governed_By => Assoc_List,
14011 Report_Errors => Errors);
14013 -- Note: previously there was a check at this point that no errors
14014 -- were detected. As a consequence of AI05-220 there may be an error
14015 -- if an inherited discriminant that controls a variant has a non-
14016 -- static constraint.
14018 -- If the tagged derivation has a type extension, collect all the
14019 -- new components therein.
14021 if Present (Record_Extension_Part (Type_Definition (Parent (Typ))))
14023 Old_C := First_Component (Typ);
14024 while Present (Old_C) loop
14025 if Original_Record_Component (Old_C) = Old_C
14026 and then Chars (Old_C) /= Name_uTag
14027 and then Chars (Old_C) /= Name_uParent
14029 Append_Elmt (Old_C, Comp_List);
14032 Next_Component (Old_C);
14036 Create_All_Components;
14039 -- If discriminants are not static, or if this is a multi-level type
14040 -- extension, we have to include all components of the parent type.
14042 Old_C := First_Component (Typ);
14043 while Present (Old_C) loop
14044 New_C := Create_Component (Old_C);
14048 Constrain_Component_Type
14049 (Old_C, Subt, Decl_Node, Typ, Constraints));
14050 Set_Is_Public (New_C, Is_Public (Subt));
14052 Next_Component (Old_C);
14057 end Create_Constrained_Components;
14059 ------------------------------------------
14060 -- Decimal_Fixed_Point_Type_Declaration --
14061 ------------------------------------------
14063 procedure Decimal_Fixed_Point_Type_Declaration
14067 Loc : constant Source_Ptr := Sloc (Def);
14068 Digs_Expr : constant Node_Id := Digits_Expression (Def);
14069 Delta_Expr : constant Node_Id := Delta_Expression (Def);
14070 Implicit_Base : Entity_Id;
14077 Check_SPARK_05_Restriction
14078 ("decimal fixed point type is not allowed", Def);
14079 Check_Restriction (No_Fixed_Point, Def);
14081 -- Create implicit base type
14084 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
14085 Set_Etype (Implicit_Base, Implicit_Base);
14087 -- Analyze and process delta expression
14089 Analyze_And_Resolve (Delta_Expr, Universal_Real);
14091 Check_Delta_Expression (Delta_Expr);
14092 Delta_Val := Expr_Value_R (Delta_Expr);
14094 -- Check delta is power of 10, and determine scale value from it
14100 Scale_Val := Uint_0;
14103 if Val < Ureal_1 then
14104 while Val < Ureal_1 loop
14105 Val := Val * Ureal_10;
14106 Scale_Val := Scale_Val + 1;
14109 if Scale_Val > 18 then
14110 Error_Msg_N ("scale exceeds maximum value of 18", Def);
14111 Scale_Val := UI_From_Int (+18);
14115 while Val > Ureal_1 loop
14116 Val := Val / Ureal_10;
14117 Scale_Val := Scale_Val - 1;
14120 if Scale_Val < -18 then
14121 Error_Msg_N ("scale is less than minimum value of -18", Def);
14122 Scale_Val := UI_From_Int (-18);
14126 if Val /= Ureal_1 then
14127 Error_Msg_N ("delta expression must be a power of 10", Def);
14128 Delta_Val := Ureal_10 ** (-Scale_Val);
14132 -- Set delta, scale and small (small = delta for decimal type)
14134 Set_Delta_Value (Implicit_Base, Delta_Val);
14135 Set_Scale_Value (Implicit_Base, Scale_Val);
14136 Set_Small_Value (Implicit_Base, Delta_Val);
14138 -- Analyze and process digits expression
14140 Analyze_And_Resolve (Digs_Expr, Any_Integer);
14141 Check_Digits_Expression (Digs_Expr);
14142 Digs_Val := Expr_Value (Digs_Expr);
14144 if Digs_Val > 18 then
14145 Digs_Val := UI_From_Int (+18);
14146 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
14149 Set_Digits_Value (Implicit_Base, Digs_Val);
14150 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
14152 -- Set range of base type from digits value for now. This will be
14153 -- expanded to represent the true underlying base range by Freeze.
14155 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
14157 -- Note: We leave size as zero for now, size will be set at freeze
14158 -- time. We have to do this for ordinary fixed-point, because the size
14159 -- depends on the specified small, and we might as well do the same for
14160 -- decimal fixed-point.
14162 pragma Assert (Esize (Implicit_Base) = Uint_0);
14164 -- If there are bounds given in the declaration use them as the
14165 -- bounds of the first named subtype.
14167 if Present (Real_Range_Specification (Def)) then
14169 RRS : constant Node_Id := Real_Range_Specification (Def);
14170 Low : constant Node_Id := Low_Bound (RRS);
14171 High : constant Node_Id := High_Bound (RRS);
14176 Analyze_And_Resolve (Low, Any_Real);
14177 Analyze_And_Resolve (High, Any_Real);
14178 Check_Real_Bound (Low);
14179 Check_Real_Bound (High);
14180 Low_Val := Expr_Value_R (Low);
14181 High_Val := Expr_Value_R (High);
14183 if Low_Val < (-Bound_Val) then
14185 ("range low bound too small for digits value", Low);
14186 Low_Val := -Bound_Val;
14189 if High_Val > Bound_Val then
14191 ("range high bound too large for digits value", High);
14192 High_Val := Bound_Val;
14195 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
14198 -- If no explicit range, use range that corresponds to given
14199 -- digits value. This will end up as the final range for the
14203 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
14206 -- Complete entity for first subtype. The inheritance of the rep item
14207 -- chain ensures that SPARK-related pragmas are not clobbered when the
14208 -- decimal fixed point type acts as a full view of a private type.
14210 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
14211 Set_Etype (T, Implicit_Base);
14212 Set_Size_Info (T, Implicit_Base);
14213 Inherit_Rep_Item_Chain (T, Implicit_Base);
14214 Set_Digits_Value (T, Digs_Val);
14215 Set_Delta_Value (T, Delta_Val);
14216 Set_Small_Value (T, Delta_Val);
14217 Set_Scale_Value (T, Scale_Val);
14218 Set_Is_Constrained (T);
14219 end Decimal_Fixed_Point_Type_Declaration;
14221 -----------------------------------
14222 -- Derive_Progenitor_Subprograms --
14223 -----------------------------------
14225 procedure Derive_Progenitor_Subprograms
14226 (Parent_Type : Entity_Id;
14227 Tagged_Type : Entity_Id)
14232 Iface_Elmt : Elmt_Id;
14233 Iface_Subp : Entity_Id;
14234 New_Subp : Entity_Id := Empty;
14235 Prim_Elmt : Elmt_Id;
14240 pragma Assert (Ada_Version >= Ada_2005
14241 and then Is_Record_Type (Tagged_Type)
14242 and then Is_Tagged_Type (Tagged_Type)
14243 and then Has_Interfaces (Tagged_Type));
14245 -- Step 1: Transfer to the full-view primitives associated with the
14246 -- partial-view that cover interface primitives. Conceptually this
14247 -- work should be done later by Process_Full_View; done here to
14248 -- simplify its implementation at later stages. It can be safely
14249 -- done here because interfaces must be visible in the partial and
14250 -- private view (RM 7.3(7.3/2)).
14252 -- Small optimization: This work is only required if the parent may
14253 -- have entities whose Alias attribute reference an interface primitive.
14254 -- Such a situation may occur if the parent is an abstract type and the
14255 -- primitive has not been yet overridden or if the parent is a generic
14256 -- formal type covering interfaces.
14258 -- If the tagged type is not abstract, it cannot have abstract
14259 -- primitives (the only entities in the list of primitives of
14260 -- non-abstract tagged types that can reference abstract primitives
14261 -- through its Alias attribute are the internal entities that have
14262 -- attribute Interface_Alias, and these entities are generated later
14263 -- by Add_Internal_Interface_Entities).
14265 if In_Private_Part (Current_Scope)
14266 and then (Is_Abstract_Type (Parent_Type)
14268 Is_Generic_Type (Parent_Type))
14270 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
14271 while Present (Elmt) loop
14272 Subp := Node (Elmt);
14274 -- At this stage it is not possible to have entities in the list
14275 -- of primitives that have attribute Interface_Alias.
14277 pragma Assert (No (Interface_Alias (Subp)));
14279 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
14281 if Is_Interface (Typ) then
14282 E := Find_Primitive_Covering_Interface
14283 (Tagged_Type => Tagged_Type,
14284 Iface_Prim => Subp);
14287 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
14289 Replace_Elmt (Elmt, E);
14290 Remove_Homonym (Subp);
14298 -- Step 2: Add primitives of progenitors that are not implemented by
14299 -- parents of Tagged_Type.
14301 if Present (Interfaces (Base_Type (Tagged_Type))) then
14302 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
14303 while Present (Iface_Elmt) loop
14304 Iface := Node (Iface_Elmt);
14306 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
14307 while Present (Prim_Elmt) loop
14308 Iface_Subp := Node (Prim_Elmt);
14310 -- Exclude derivation of predefined primitives except those
14311 -- that come from source, or are inherited from one that comes
14312 -- from source. Required to catch declarations of equality
14313 -- operators of interfaces. For example:
14315 -- type Iface is interface;
14316 -- function "=" (Left, Right : Iface) return Boolean;
14318 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
14319 or else Comes_From_Source (Ultimate_Alias (Iface_Subp))
14321 E := Find_Primitive_Covering_Interface
14322 (Tagged_Type => Tagged_Type,
14323 Iface_Prim => Iface_Subp);
14325 -- If not found we derive a new primitive leaving its alias
14326 -- attribute referencing the interface primitive.
14330 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14332 -- Ada 2012 (AI05-0197): If the covering primitive's name
14333 -- differs from the name of the interface primitive then it
14334 -- is a private primitive inherited from a parent type. In
14335 -- such case, given that Tagged_Type covers the interface,
14336 -- the inherited private primitive becomes visible. For such
14337 -- purpose we add a new entity that renames the inherited
14338 -- private primitive.
14340 elsif Chars (E) /= Chars (Iface_Subp) then
14341 pragma Assert (Has_Suffix (E, 'P'));
14343 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14344 Set_Alias (New_Subp, E);
14345 Set_Is_Abstract_Subprogram (New_Subp,
14346 Is_Abstract_Subprogram (E));
14348 -- Propagate to the full view interface entities associated
14349 -- with the partial view.
14351 elsif In_Private_Part (Current_Scope)
14352 and then Present (Alias (E))
14353 and then Alias (E) = Iface_Subp
14355 List_Containing (Parent (E)) /=
14356 Private_Declarations
14358 (Unit_Declaration_Node (Current_Scope)))
14360 Append_Elmt (E, Primitive_Operations (Tagged_Type));
14364 Next_Elmt (Prim_Elmt);
14367 Next_Elmt (Iface_Elmt);
14370 end Derive_Progenitor_Subprograms;
14372 -----------------------
14373 -- Derive_Subprogram --
14374 -----------------------
14376 procedure Derive_Subprogram
14377 (New_Subp : in out Entity_Id;
14378 Parent_Subp : Entity_Id;
14379 Derived_Type : Entity_Id;
14380 Parent_Type : Entity_Id;
14381 Actual_Subp : Entity_Id := Empty)
14383 Formal : Entity_Id;
14384 -- Formal parameter of parent primitive operation
14386 Formal_Of_Actual : Entity_Id;
14387 -- Formal parameter of actual operation, when the derivation is to
14388 -- create a renaming for a primitive operation of an actual in an
14391 New_Formal : Entity_Id;
14392 -- Formal of inherited operation
14394 Visible_Subp : Entity_Id := Parent_Subp;
14396 function Is_Private_Overriding return Boolean;
14397 -- If Subp is a private overriding of a visible operation, the inherited
14398 -- operation derives from the overridden op (even though its body is the
14399 -- overriding one) and the inherited operation is visible now. See
14400 -- sem_disp to see the full details of the handling of the overridden
14401 -- subprogram, which is removed from the list of primitive operations of
14402 -- the type. The overridden subprogram is saved locally in Visible_Subp,
14403 -- and used to diagnose abstract operations that need overriding in the
14406 procedure Replace_Type (Id, New_Id : Entity_Id);
14407 -- When the type is an anonymous access type, create a new access type
14408 -- designating the derived type.
14410 procedure Set_Derived_Name;
14411 -- This procedure sets the appropriate Chars name for New_Subp. This
14412 -- is normally just a copy of the parent name. An exception arises for
14413 -- type support subprograms, where the name is changed to reflect the
14414 -- name of the derived type, e.g. if type foo is derived from type bar,
14415 -- then a procedure barDA is derived with a name fooDA.
14417 ---------------------------
14418 -- Is_Private_Overriding --
14419 ---------------------------
14421 function Is_Private_Overriding return Boolean is
14425 -- If the parent is not a dispatching operation there is no
14426 -- need to investigate overridings
14428 if not Is_Dispatching_Operation (Parent_Subp) then
14432 -- The visible operation that is overridden is a homonym of the
14433 -- parent subprogram. We scan the homonym chain to find the one
14434 -- whose alias is the subprogram we are deriving.
14436 Prev := Current_Entity (Parent_Subp);
14437 while Present (Prev) loop
14438 if Ekind (Prev) = Ekind (Parent_Subp)
14439 and then Alias (Prev) = Parent_Subp
14440 and then Scope (Parent_Subp) = Scope (Prev)
14441 and then not Is_Hidden (Prev)
14443 Visible_Subp := Prev;
14447 Prev := Homonym (Prev);
14451 end Is_Private_Overriding;
14457 procedure Replace_Type (Id, New_Id : Entity_Id) is
14458 Id_Type : constant Entity_Id := Etype (Id);
14459 Acc_Type : Entity_Id;
14460 Par : constant Node_Id := Parent (Derived_Type);
14463 -- When the type is an anonymous access type, create a new access
14464 -- type designating the derived type. This itype must be elaborated
14465 -- at the point of the derivation, not on subsequent calls that may
14466 -- be out of the proper scope for Gigi, so we insert a reference to
14467 -- it after the derivation.
14469 if Ekind (Id_Type) = E_Anonymous_Access_Type then
14471 Desig_Typ : Entity_Id := Designated_Type (Id_Type);
14474 if Ekind (Desig_Typ) = E_Record_Type_With_Private
14475 and then Present (Full_View (Desig_Typ))
14476 and then not Is_Private_Type (Parent_Type)
14478 Desig_Typ := Full_View (Desig_Typ);
14481 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
14483 -- Ada 2005 (AI-251): Handle also derivations of abstract
14484 -- interface primitives.
14486 or else (Is_Interface (Desig_Typ)
14487 and then not Is_Class_Wide_Type (Desig_Typ))
14489 Acc_Type := New_Copy (Id_Type);
14490 Set_Etype (Acc_Type, Acc_Type);
14491 Set_Scope (Acc_Type, New_Subp);
14493 -- Set size of anonymous access type. If we have an access
14494 -- to an unconstrained array, this is a fat pointer, so it
14495 -- is sizes at twice addtress size.
14497 if Is_Array_Type (Desig_Typ)
14498 and then not Is_Constrained (Desig_Typ)
14500 Init_Size (Acc_Type, 2 * System_Address_Size);
14502 -- Other cases use a thin pointer
14505 Init_Size (Acc_Type, System_Address_Size);
14508 -- Set remaining characterstics of anonymous access type
14510 Init_Alignment (Acc_Type);
14511 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
14513 Set_Etype (New_Id, Acc_Type);
14514 Set_Scope (New_Id, New_Subp);
14516 -- Create a reference to it
14518 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
14521 Set_Etype (New_Id, Id_Type);
14525 -- In Ada2012, a formal may have an incomplete type but the type
14526 -- derivation that inherits the primitive follows the full view.
14528 elsif Base_Type (Id_Type) = Base_Type (Parent_Type)
14530 (Ekind (Id_Type) = E_Record_Type_With_Private
14531 and then Present (Full_View (Id_Type))
14533 Base_Type (Full_View (Id_Type)) = Base_Type (Parent_Type))
14535 (Ada_Version >= Ada_2012
14536 and then Ekind (Id_Type) = E_Incomplete_Type
14537 and then Full_View (Id_Type) = Parent_Type)
14539 -- Constraint checks on formals are generated during expansion,
14540 -- based on the signature of the original subprogram. The bounds
14541 -- of the derived type are not relevant, and thus we can use
14542 -- the base type for the formals. However, the return type may be
14543 -- used in a context that requires that the proper static bounds
14544 -- be used (a case statement, for example) and for those cases
14545 -- we must use the derived type (first subtype), not its base.
14547 -- If the derived_type_definition has no constraints, we know that
14548 -- the derived type has the same constraints as the first subtype
14549 -- of the parent, and we can also use it rather than its base,
14550 -- which can lead to more efficient code.
14552 if Etype (Id) = Parent_Type then
14553 if Is_Scalar_Type (Parent_Type)
14555 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
14557 Set_Etype (New_Id, Derived_Type);
14559 elsif Nkind (Par) = N_Full_Type_Declaration
14561 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
14564 (Subtype_Indication (Type_Definition (Par)))
14566 Set_Etype (New_Id, Derived_Type);
14569 Set_Etype (New_Id, Base_Type (Derived_Type));
14573 Set_Etype (New_Id, Base_Type (Derived_Type));
14577 Set_Etype (New_Id, Etype (Id));
14581 ----------------------
14582 -- Set_Derived_Name --
14583 ----------------------
14585 procedure Set_Derived_Name is
14586 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
14588 if Nm = TSS_Null then
14589 Set_Chars (New_Subp, Chars (Parent_Subp));
14591 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
14593 end Set_Derived_Name;
14595 -- Start of processing for Derive_Subprogram
14598 New_Subp := New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
14599 Set_Ekind (New_Subp, Ekind (Parent_Subp));
14601 -- Check whether the inherited subprogram is a private operation that
14602 -- should be inherited but not yet made visible. Such subprograms can
14603 -- become visible at a later point (e.g., the private part of a public
14604 -- child unit) via Declare_Inherited_Private_Subprograms. If the
14605 -- following predicate is true, then this is not such a private
14606 -- operation and the subprogram simply inherits the name of the parent
14607 -- subprogram. Note the special check for the names of controlled
14608 -- operations, which are currently exempted from being inherited with
14609 -- a hidden name because they must be findable for generation of
14610 -- implicit run-time calls.
14612 if not Is_Hidden (Parent_Subp)
14613 or else Is_Internal (Parent_Subp)
14614 or else Is_Private_Overriding
14615 or else Is_Internal_Name (Chars (Parent_Subp))
14616 or else Nam_In (Chars (Parent_Subp), Name_Initialize,
14622 -- An inherited dispatching equality will be overridden by an internally
14623 -- generated one, or by an explicit one, so preserve its name and thus
14624 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
14625 -- private operation it may become invisible if the full view has
14626 -- progenitors, and the dispatch table will be malformed.
14627 -- We check that the type is limited to handle the anomalous declaration
14628 -- of Limited_Controlled, which is derived from a non-limited type, and
14629 -- which is handled specially elsewhere as well.
14631 elsif Chars (Parent_Subp) = Name_Op_Eq
14632 and then Is_Dispatching_Operation (Parent_Subp)
14633 and then Etype (Parent_Subp) = Standard_Boolean
14634 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
14636 Etype (First_Formal (Parent_Subp)) =
14637 Etype (Next_Formal (First_Formal (Parent_Subp)))
14641 -- If parent is hidden, this can be a regular derivation if the
14642 -- parent is immediately visible in a non-instantiating context,
14643 -- or if we are in the private part of an instance. This test
14644 -- should still be refined ???
14646 -- The test for In_Instance_Not_Visible avoids inheriting the derived
14647 -- operation as a non-visible operation in cases where the parent
14648 -- subprogram might not be visible now, but was visible within the
14649 -- original generic, so it would be wrong to make the inherited
14650 -- subprogram non-visible now. (Not clear if this test is fully
14651 -- correct; are there any cases where we should declare the inherited
14652 -- operation as not visible to avoid it being overridden, e.g., when
14653 -- the parent type is a generic actual with private primitives ???)
14655 -- (they should be treated the same as other private inherited
14656 -- subprograms, but it's not clear how to do this cleanly). ???
14658 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
14659 and then Is_Immediately_Visible (Parent_Subp)
14660 and then not In_Instance)
14661 or else In_Instance_Not_Visible
14665 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
14666 -- overrides an interface primitive because interface primitives
14667 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
14669 elsif Ada_Version >= Ada_2005
14670 and then Is_Dispatching_Operation (Parent_Subp)
14671 and then Covers_Some_Interface (Parent_Subp)
14675 -- Otherwise, the type is inheriting a private operation, so enter
14676 -- it with a special name so it can't be overridden.
14679 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
14682 Set_Parent (New_Subp, Parent (Derived_Type));
14684 if Present (Actual_Subp) then
14685 Replace_Type (Actual_Subp, New_Subp);
14687 Replace_Type (Parent_Subp, New_Subp);
14690 Conditional_Delay (New_Subp, Parent_Subp);
14692 -- If we are creating a renaming for a primitive operation of an
14693 -- actual of a generic derived type, we must examine the signature
14694 -- of the actual primitive, not that of the generic formal, which for
14695 -- example may be an interface. However the name and initial value
14696 -- of the inherited operation are those of the formal primitive.
14698 Formal := First_Formal (Parent_Subp);
14700 if Present (Actual_Subp) then
14701 Formal_Of_Actual := First_Formal (Actual_Subp);
14703 Formal_Of_Actual := Empty;
14706 while Present (Formal) loop
14707 New_Formal := New_Copy (Formal);
14709 -- Normally we do not go copying parents, but in the case of
14710 -- formals, we need to link up to the declaration (which is the
14711 -- parameter specification), and it is fine to link up to the
14712 -- original formal's parameter specification in this case.
14714 Set_Parent (New_Formal, Parent (Formal));
14715 Append_Entity (New_Formal, New_Subp);
14717 if Present (Formal_Of_Actual) then
14718 Replace_Type (Formal_Of_Actual, New_Formal);
14719 Next_Formal (Formal_Of_Actual);
14721 Replace_Type (Formal, New_Formal);
14724 Next_Formal (Formal);
14727 -- If this derivation corresponds to a tagged generic actual, then
14728 -- primitive operations rename those of the actual. Otherwise the
14729 -- primitive operations rename those of the parent type, If the parent
14730 -- renames an intrinsic operator, so does the new subprogram. We except
14731 -- concatenation, which is always properly typed, and does not get
14732 -- expanded as other intrinsic operations.
14734 if No (Actual_Subp) then
14735 if Is_Intrinsic_Subprogram (Parent_Subp) then
14736 Set_Is_Intrinsic_Subprogram (New_Subp);
14738 if Present (Alias (Parent_Subp))
14739 and then Chars (Parent_Subp) /= Name_Op_Concat
14741 Set_Alias (New_Subp, Alias (Parent_Subp));
14743 Set_Alias (New_Subp, Parent_Subp);
14747 Set_Alias (New_Subp, Parent_Subp);
14751 Set_Alias (New_Subp, Actual_Subp);
14754 -- Inherit the "ghostness" from the parent subprogram
14756 if Is_Ghost_Entity (Alias (New_Subp)) then
14757 Set_Is_Ghost_Entity (New_Subp);
14760 -- Derived subprograms of a tagged type must inherit the convention
14761 -- of the parent subprogram (a requirement of AI-117). Derived
14762 -- subprograms of untagged types simply get convention Ada by default.
14764 -- If the derived type is a tagged generic formal type with unknown
14765 -- discriminants, its convention is intrinsic (RM 6.3.1 (8)).
14767 -- However, if the type is derived from a generic formal, the further
14768 -- inherited subprogram has the convention of the non-generic ancestor.
14769 -- Otherwise there would be no way to override the operation.
14770 -- (This is subject to forthcoming ARG discussions).
14772 if Is_Tagged_Type (Derived_Type) then
14773 if Is_Generic_Type (Derived_Type)
14774 and then Has_Unknown_Discriminants (Derived_Type)
14776 Set_Convention (New_Subp, Convention_Intrinsic);
14779 if Is_Generic_Type (Parent_Type)
14780 and then Has_Unknown_Discriminants (Parent_Type)
14782 Set_Convention (New_Subp, Convention (Alias (Parent_Subp)));
14784 Set_Convention (New_Subp, Convention (Parent_Subp));
14789 -- Predefined controlled operations retain their name even if the parent
14790 -- is hidden (see above), but they are not primitive operations if the
14791 -- ancestor is not visible, for example if the parent is a private
14792 -- extension completed with a controlled extension. Note that a full
14793 -- type that is controlled can break privacy: the flag Is_Controlled is
14794 -- set on both views of the type.
14796 if Is_Controlled (Parent_Type)
14797 and then Nam_In (Chars (Parent_Subp), Name_Initialize,
14800 and then Is_Hidden (Parent_Subp)
14801 and then not Is_Visibly_Controlled (Parent_Type)
14803 Set_Is_Hidden (New_Subp);
14806 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
14807 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
14809 if Ekind (Parent_Subp) = E_Procedure then
14810 Set_Is_Valued_Procedure
14811 (New_Subp, Is_Valued_Procedure (Parent_Subp));
14813 Set_Has_Controlling_Result
14814 (New_Subp, Has_Controlling_Result (Parent_Subp));
14817 -- No_Return must be inherited properly. If this is overridden in the
14818 -- case of a dispatching operation, then a check is made in Sem_Disp
14819 -- that the overriding operation is also No_Return (no such check is
14820 -- required for the case of non-dispatching operation.
14822 Set_No_Return (New_Subp, No_Return (Parent_Subp));
14824 -- A derived function with a controlling result is abstract. If the
14825 -- Derived_Type is a nonabstract formal generic derived type, then
14826 -- inherited operations are not abstract: the required check is done at
14827 -- instantiation time. If the derivation is for a generic actual, the
14828 -- function is not abstract unless the actual is.
14830 if Is_Generic_Type (Derived_Type)
14831 and then not Is_Abstract_Type (Derived_Type)
14835 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
14836 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
14838 -- A subprogram subject to pragma Extensions_Visible with value False
14839 -- requires overriding if the subprogram has at least one controlling
14840 -- OUT parameter (SPARK RM 6.1.7(6)).
14842 elsif Ada_Version >= Ada_2005
14843 and then (Is_Abstract_Subprogram (Alias (New_Subp))
14844 or else (Is_Tagged_Type (Derived_Type)
14845 and then Etype (New_Subp) = Derived_Type
14846 and then not Is_Null_Extension (Derived_Type))
14847 or else (Is_Tagged_Type (Derived_Type)
14848 and then Ekind (Etype (New_Subp)) =
14849 E_Anonymous_Access_Type
14850 and then Designated_Type (Etype (New_Subp)) =
14852 and then not Is_Null_Extension (Derived_Type))
14853 or else (Comes_From_Source (Alias (New_Subp))
14854 and then Is_EVF_Procedure (Alias (New_Subp))))
14855 and then No (Actual_Subp)
14857 if not Is_Tagged_Type (Derived_Type)
14858 or else Is_Abstract_Type (Derived_Type)
14859 or else Is_Abstract_Subprogram (Alias (New_Subp))
14861 Set_Is_Abstract_Subprogram (New_Subp);
14863 Set_Requires_Overriding (New_Subp);
14866 elsif Ada_Version < Ada_2005
14867 and then (Is_Abstract_Subprogram (Alias (New_Subp))
14868 or else (Is_Tagged_Type (Derived_Type)
14869 and then Etype (New_Subp) = Derived_Type
14870 and then No (Actual_Subp)))
14872 Set_Is_Abstract_Subprogram (New_Subp);
14874 -- AI05-0097 : an inherited operation that dispatches on result is
14875 -- abstract if the derived type is abstract, even if the parent type
14876 -- is concrete and the derived type is a null extension.
14878 elsif Has_Controlling_Result (Alias (New_Subp))
14879 and then Is_Abstract_Type (Etype (New_Subp))
14881 Set_Is_Abstract_Subprogram (New_Subp);
14883 -- Finally, if the parent type is abstract we must verify that all
14884 -- inherited operations are either non-abstract or overridden, or that
14885 -- the derived type itself is abstract (this check is performed at the
14886 -- end of a package declaration, in Check_Abstract_Overriding). A
14887 -- private overriding in the parent type will not be visible in the
14888 -- derivation if we are not in an inner package or in a child unit of
14889 -- the parent type, in which case the abstractness of the inherited
14890 -- operation is carried to the new subprogram.
14892 elsif Is_Abstract_Type (Parent_Type)
14893 and then not In_Open_Scopes (Scope (Parent_Type))
14894 and then Is_Private_Overriding
14895 and then Is_Abstract_Subprogram (Visible_Subp)
14897 if No (Actual_Subp) then
14898 Set_Alias (New_Subp, Visible_Subp);
14899 Set_Is_Abstract_Subprogram (New_Subp, True);
14902 -- If this is a derivation for an instance of a formal derived
14903 -- type, abstractness comes from the primitive operation of the
14904 -- actual, not from the operation inherited from the ancestor.
14906 Set_Is_Abstract_Subprogram
14907 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
14911 New_Overloaded_Entity (New_Subp, Derived_Type);
14913 -- Check for case of a derived subprogram for the instantiation of a
14914 -- formal derived tagged type, if so mark the subprogram as dispatching
14915 -- and inherit the dispatching attributes of the actual subprogram. The
14916 -- derived subprogram is effectively renaming of the actual subprogram,
14917 -- so it needs to have the same attributes as the actual.
14919 if Present (Actual_Subp)
14920 and then Is_Dispatching_Operation (Actual_Subp)
14922 Set_Is_Dispatching_Operation (New_Subp);
14924 if Present (DTC_Entity (Actual_Subp)) then
14925 Set_DTC_Entity (New_Subp, DTC_Entity (Actual_Subp));
14926 Set_DT_Position_Value (New_Subp, DT_Position (Actual_Subp));
14930 -- Indicate that a derived subprogram does not require a body and that
14931 -- it does not require processing of default expressions.
14933 Set_Has_Completion (New_Subp);
14934 Set_Default_Expressions_Processed (New_Subp);
14936 if Ekind (New_Subp) = E_Function then
14937 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
14939 end Derive_Subprogram;
14941 ------------------------
14942 -- Derive_Subprograms --
14943 ------------------------
14945 procedure Derive_Subprograms
14946 (Parent_Type : Entity_Id;
14947 Derived_Type : Entity_Id;
14948 Generic_Actual : Entity_Id := Empty)
14950 Op_List : constant Elist_Id :=
14951 Collect_Primitive_Operations (Parent_Type);
14953 function Check_Derived_Type return Boolean;
14954 -- Check that all the entities derived from Parent_Type are found in
14955 -- the list of primitives of Derived_Type exactly in the same order.
14957 procedure Derive_Interface_Subprogram
14958 (New_Subp : in out Entity_Id;
14960 Actual_Subp : Entity_Id);
14961 -- Derive New_Subp from the ultimate alias of the parent subprogram Subp
14962 -- (which is an interface primitive). If Generic_Actual is present then
14963 -- Actual_Subp is the actual subprogram corresponding with the generic
14964 -- subprogram Subp.
14966 function Check_Derived_Type return Boolean is
14970 New_Subp : Entity_Id;
14975 -- Traverse list of entities in the current scope searching for
14976 -- an incomplete type whose full-view is derived type
14978 E := First_Entity (Scope (Derived_Type));
14979 while Present (E) and then E /= Derived_Type loop
14980 if Ekind (E) = E_Incomplete_Type
14981 and then Present (Full_View (E))
14982 and then Full_View (E) = Derived_Type
14984 -- Disable this test if Derived_Type completes an incomplete
14985 -- type because in such case more primitives can be added
14986 -- later to the list of primitives of Derived_Type by routine
14987 -- Process_Incomplete_Dependents
14992 E := Next_Entity (E);
14995 List := Collect_Primitive_Operations (Derived_Type);
14996 Elmt := First_Elmt (List);
14998 Op_Elmt := First_Elmt (Op_List);
14999 while Present (Op_Elmt) loop
15000 Subp := Node (Op_Elmt);
15001 New_Subp := Node (Elmt);
15003 -- At this early stage Derived_Type has no entities with attribute
15004 -- Interface_Alias. In addition, such primitives are always
15005 -- located at the end of the list of primitives of Parent_Type.
15006 -- Therefore, if found we can safely stop processing pending
15009 exit when Present (Interface_Alias (Subp));
15011 -- Handle hidden entities
15013 if not Is_Predefined_Dispatching_Operation (Subp)
15014 and then Is_Hidden (Subp)
15016 if Present (New_Subp)
15017 and then Primitive_Names_Match (Subp, New_Subp)
15023 if not Present (New_Subp)
15024 or else Ekind (Subp) /= Ekind (New_Subp)
15025 or else not Primitive_Names_Match (Subp, New_Subp)
15033 Next_Elmt (Op_Elmt);
15037 end Check_Derived_Type;
15039 ---------------------------------
15040 -- Derive_Interface_Subprogram --
15041 ---------------------------------
15043 procedure Derive_Interface_Subprogram
15044 (New_Subp : in out Entity_Id;
15046 Actual_Subp : Entity_Id)
15048 Iface_Subp : constant Entity_Id := Ultimate_Alias (Subp);
15049 Iface_Type : constant Entity_Id := Find_Dispatching_Type (Iface_Subp);
15052 pragma Assert (Is_Interface (Iface_Type));
15055 (New_Subp => New_Subp,
15056 Parent_Subp => Iface_Subp,
15057 Derived_Type => Derived_Type,
15058 Parent_Type => Iface_Type,
15059 Actual_Subp => Actual_Subp);
15061 -- Given that this new interface entity corresponds with a primitive
15062 -- of the parent that was not overridden we must leave it associated
15063 -- with its parent primitive to ensure that it will share the same
15064 -- dispatch table slot when overridden. We must set the Alias to Subp
15065 -- (instead of Iface_Subp), and we must fix Is_Abstract_Subprogram
15066 -- (in case we inherited Subp from Iface_Type via a nonabstract
15067 -- generic formal type).
15069 if No (Actual_Subp) then
15070 Set_Alias (New_Subp, Subp);
15073 T : Entity_Id := Find_Dispatching_Type (Subp);
15075 while Etype (T) /= T loop
15076 if Is_Generic_Type (T) and then not Is_Abstract_Type (T) then
15077 Set_Is_Abstract_Subprogram (New_Subp, False);
15085 -- For instantiations this is not needed since the previous call to
15086 -- Derive_Subprogram leaves the entity well decorated.
15089 pragma Assert (Alias (New_Subp) = Actual_Subp);
15092 end Derive_Interface_Subprogram;
15096 Alias_Subp : Entity_Id;
15097 Act_List : Elist_Id;
15098 Act_Elmt : Elmt_Id;
15099 Act_Subp : Entity_Id := Empty;
15101 Need_Search : Boolean := False;
15102 New_Subp : Entity_Id := Empty;
15103 Parent_Base : Entity_Id;
15106 -- Start of processing for Derive_Subprograms
15109 if Ekind (Parent_Type) = E_Record_Type_With_Private
15110 and then Has_Discriminants (Parent_Type)
15111 and then Present (Full_View (Parent_Type))
15113 Parent_Base := Full_View (Parent_Type);
15115 Parent_Base := Parent_Type;
15118 if Present (Generic_Actual) then
15119 Act_List := Collect_Primitive_Operations (Generic_Actual);
15120 Act_Elmt := First_Elmt (Act_List);
15122 Act_List := No_Elist;
15123 Act_Elmt := No_Elmt;
15126 -- Derive primitives inherited from the parent. Note that if the generic
15127 -- actual is present, this is not really a type derivation, it is a
15128 -- completion within an instance.
15130 -- Case 1: Derived_Type does not implement interfaces
15132 if not Is_Tagged_Type (Derived_Type)
15133 or else (not Has_Interfaces (Derived_Type)
15134 and then not (Present (Generic_Actual)
15135 and then Has_Interfaces (Generic_Actual)))
15137 Elmt := First_Elmt (Op_List);
15138 while Present (Elmt) loop
15139 Subp := Node (Elmt);
15141 -- Literals are derived earlier in the process of building the
15142 -- derived type, and are skipped here.
15144 if Ekind (Subp) = E_Enumeration_Literal then
15147 -- The actual is a direct descendant and the common primitive
15148 -- operations appear in the same order.
15150 -- If the generic parent type is present, the derived type is an
15151 -- instance of a formal derived type, and within the instance its
15152 -- operations are those of the actual. We derive from the formal
15153 -- type but make the inherited operations aliases of the
15154 -- corresponding operations of the actual.
15157 pragma Assert (No (Node (Act_Elmt))
15158 or else (Primitive_Names_Match (Subp, Node (Act_Elmt))
15161 (Subp, Node (Act_Elmt),
15162 Skip_Controlling_Formals => True)));
15165 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
15167 if Present (Act_Elmt) then
15168 Next_Elmt (Act_Elmt);
15175 -- Case 2: Derived_Type implements interfaces
15178 -- If the parent type has no predefined primitives we remove
15179 -- predefined primitives from the list of primitives of generic
15180 -- actual to simplify the complexity of this algorithm.
15182 if Present (Generic_Actual) then
15184 Has_Predefined_Primitives : Boolean := False;
15187 -- Check if the parent type has predefined primitives
15189 Elmt := First_Elmt (Op_List);
15190 while Present (Elmt) loop
15191 Subp := Node (Elmt);
15193 if Is_Predefined_Dispatching_Operation (Subp)
15194 and then not Comes_From_Source (Ultimate_Alias (Subp))
15196 Has_Predefined_Primitives := True;
15203 -- Remove predefined primitives of Generic_Actual. We must use
15204 -- an auxiliary list because in case of tagged types the value
15205 -- returned by Collect_Primitive_Operations is the value stored
15206 -- in its Primitive_Operations attribute (and we don't want to
15207 -- modify its current contents).
15209 if not Has_Predefined_Primitives then
15211 Aux_List : constant Elist_Id := New_Elmt_List;
15214 Elmt := First_Elmt (Act_List);
15215 while Present (Elmt) loop
15216 Subp := Node (Elmt);
15218 if not Is_Predefined_Dispatching_Operation (Subp)
15219 or else Comes_From_Source (Subp)
15221 Append_Elmt (Subp, Aux_List);
15227 Act_List := Aux_List;
15231 Act_Elmt := First_Elmt (Act_List);
15232 Act_Subp := Node (Act_Elmt);
15236 -- Stage 1: If the generic actual is not present we derive the
15237 -- primitives inherited from the parent type. If the generic parent
15238 -- type is present, the derived type is an instance of a formal
15239 -- derived type, and within the instance its operations are those of
15240 -- the actual. We derive from the formal type but make the inherited
15241 -- operations aliases of the corresponding operations of the actual.
15243 Elmt := First_Elmt (Op_List);
15244 while Present (Elmt) loop
15245 Subp := Node (Elmt);
15246 Alias_Subp := Ultimate_Alias (Subp);
15248 -- Do not derive internal entities of the parent that link
15249 -- interface primitives with their covering primitive. These
15250 -- entities will be added to this type when frozen.
15252 if Present (Interface_Alias (Subp)) then
15256 -- If the generic actual is present find the corresponding
15257 -- operation in the generic actual. If the parent type is a
15258 -- direct ancestor of the derived type then, even if it is an
15259 -- interface, the operations are inherited from the primary
15260 -- dispatch table and are in the proper order. If we detect here
15261 -- that primitives are not in the same order we traverse the list
15262 -- of primitive operations of the actual to find the one that
15263 -- implements the interface primitive.
15267 (Present (Generic_Actual)
15268 and then Present (Act_Subp)
15270 (Primitive_Names_Match (Subp, Act_Subp)
15272 Type_Conformant (Subp, Act_Subp,
15273 Skip_Controlling_Formals => True)))
15275 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual,
15276 Use_Full_View => True));
15278 -- Remember that we need searching for all pending primitives
15280 Need_Search := True;
15282 -- Handle entities associated with interface primitives
15284 if Present (Alias_Subp)
15285 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
15286 and then not Is_Predefined_Dispatching_Operation (Subp)
15288 -- Search for the primitive in the homonym chain
15291 Find_Primitive_Covering_Interface
15292 (Tagged_Type => Generic_Actual,
15293 Iface_Prim => Alias_Subp);
15295 -- Previous search may not locate primitives covering
15296 -- interfaces defined in generics units or instantiations.
15297 -- (it fails if the covering primitive has formals whose
15298 -- type is also defined in generics or instantiations).
15299 -- In such case we search in the list of primitives of the
15300 -- generic actual for the internal entity that links the
15301 -- interface primitive and the covering primitive.
15304 and then Is_Generic_Type (Parent_Type)
15306 -- This code has been designed to handle only generic
15307 -- formals that implement interfaces that are defined
15308 -- in a generic unit or instantiation. If this code is
15309 -- needed for other cases we must review it because
15310 -- (given that it relies on Original_Location to locate
15311 -- the primitive of Generic_Actual that covers the
15312 -- interface) it could leave linked through attribute
15313 -- Alias entities of unrelated instantiations).
15317 (Scope (Find_Dispatching_Type (Alias_Subp)))
15319 Instantiation_Depth
15320 (Sloc (Find_Dispatching_Type (Alias_Subp))) > 0);
15323 Iface_Prim_Loc : constant Source_Ptr :=
15324 Original_Location (Sloc (Alias_Subp));
15331 First_Elmt (Primitive_Operations (Generic_Actual));
15333 Search : while Present (Elmt) loop
15334 Prim := Node (Elmt);
15336 if Present (Interface_Alias (Prim))
15337 and then Original_Location
15338 (Sloc (Interface_Alias (Prim))) =
15341 Act_Subp := Alias (Prim);
15350 pragma Assert (Present (Act_Subp)
15351 or else Is_Abstract_Type (Generic_Actual)
15352 or else Serious_Errors_Detected > 0);
15354 -- Handle predefined primitives plus the rest of user-defined
15358 Act_Elmt := First_Elmt (Act_List);
15359 while Present (Act_Elmt) loop
15360 Act_Subp := Node (Act_Elmt);
15362 exit when Primitive_Names_Match (Subp, Act_Subp)
15363 and then Type_Conformant
15365 Skip_Controlling_Formals => True)
15366 and then No (Interface_Alias (Act_Subp));
15368 Next_Elmt (Act_Elmt);
15371 if No (Act_Elmt) then
15377 -- Case 1: If the parent is a limited interface then it has the
15378 -- predefined primitives of synchronized interfaces. However, the
15379 -- actual type may be a non-limited type and hence it does not
15380 -- have such primitives.
15382 if Present (Generic_Actual)
15383 and then not Present (Act_Subp)
15384 and then Is_Limited_Interface (Parent_Base)
15385 and then Is_Predefined_Interface_Primitive (Subp)
15389 -- Case 2: Inherit entities associated with interfaces that were
15390 -- not covered by the parent type. We exclude here null interface
15391 -- primitives because they do not need special management.
15393 -- We also exclude interface operations that are renamings. If the
15394 -- subprogram is an explicit renaming of an interface primitive,
15395 -- it is a regular primitive operation, and the presence of its
15396 -- alias is not relevant: it has to be derived like any other
15399 elsif Present (Alias (Subp))
15400 and then Nkind (Unit_Declaration_Node (Subp)) /=
15401 N_Subprogram_Renaming_Declaration
15402 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
15404 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
15405 and then Null_Present (Parent (Alias_Subp)))
15407 -- If this is an abstract private type then we transfer the
15408 -- derivation of the interface primitive from the partial view
15409 -- to the full view. This is safe because all the interfaces
15410 -- must be visible in the partial view. Done to avoid adding
15411 -- a new interface derivation to the private part of the
15412 -- enclosing package; otherwise this new derivation would be
15413 -- decorated as hidden when the analysis of the enclosing
15414 -- package completes.
15416 if Is_Abstract_Type (Derived_Type)
15417 and then In_Private_Part (Current_Scope)
15418 and then Has_Private_Declaration (Derived_Type)
15421 Partial_View : Entity_Id;
15426 Partial_View := First_Entity (Current_Scope);
15428 exit when No (Partial_View)
15429 or else (Has_Private_Declaration (Partial_View)
15431 Full_View (Partial_View) = Derived_Type);
15433 Next_Entity (Partial_View);
15436 -- If the partial view was not found then the source code
15437 -- has errors and the derivation is not needed.
15439 if Present (Partial_View) then
15441 First_Elmt (Primitive_Operations (Partial_View));
15442 while Present (Elmt) loop
15443 Ent := Node (Elmt);
15445 if Present (Alias (Ent))
15446 and then Ultimate_Alias (Ent) = Alias (Subp)
15449 (Ent, Primitive_Operations (Derived_Type));
15456 -- If the interface primitive was not found in the
15457 -- partial view then this interface primitive was
15458 -- overridden. We add a derivation to activate in
15459 -- Derive_Progenitor_Subprograms the machinery to
15463 Derive_Interface_Subprogram
15464 (New_Subp => New_Subp,
15466 Actual_Subp => Act_Subp);
15471 Derive_Interface_Subprogram
15472 (New_Subp => New_Subp,
15474 Actual_Subp => Act_Subp);
15477 -- Case 3: Common derivation
15481 (New_Subp => New_Subp,
15482 Parent_Subp => Subp,
15483 Derived_Type => Derived_Type,
15484 Parent_Type => Parent_Base,
15485 Actual_Subp => Act_Subp);
15488 -- No need to update Act_Elm if we must search for the
15489 -- corresponding operation in the generic actual
15492 and then Present (Act_Elmt)
15494 Next_Elmt (Act_Elmt);
15495 Act_Subp := Node (Act_Elmt);
15502 -- Inherit additional operations from progenitors. If the derived
15503 -- type is a generic actual, there are not new primitive operations
15504 -- for the type because it has those of the actual, and therefore
15505 -- nothing needs to be done. The renamings generated above are not
15506 -- primitive operations, and their purpose is simply to make the
15507 -- proper operations visible within an instantiation.
15509 if No (Generic_Actual) then
15510 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
15514 -- Final check: Direct descendants must have their primitives in the
15515 -- same order. We exclude from this test untagged types and instances
15516 -- of formal derived types. We skip this test if we have already
15517 -- reported serious errors in the sources.
15519 pragma Assert (not Is_Tagged_Type (Derived_Type)
15520 or else Present (Generic_Actual)
15521 or else Serious_Errors_Detected > 0
15522 or else Check_Derived_Type);
15523 end Derive_Subprograms;
15525 --------------------------------
15526 -- Derived_Standard_Character --
15527 --------------------------------
15529 procedure Derived_Standard_Character
15531 Parent_Type : Entity_Id;
15532 Derived_Type : Entity_Id)
15534 Loc : constant Source_Ptr := Sloc (N);
15535 Def : constant Node_Id := Type_Definition (N);
15536 Indic : constant Node_Id := Subtype_Indication (Def);
15537 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
15538 Implicit_Base : constant Entity_Id :=
15540 (E_Enumeration_Type, N, Derived_Type, 'B');
15546 Discard_Node (Process_Subtype (Indic, N));
15548 Set_Etype (Implicit_Base, Parent_Base);
15549 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
15550 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
15552 Set_Is_Character_Type (Implicit_Base, True);
15553 Set_Has_Delayed_Freeze (Implicit_Base);
15555 -- The bounds of the implicit base are the bounds of the parent base.
15556 -- Note that their type is the parent base.
15558 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
15559 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
15561 Set_Scalar_Range (Implicit_Base,
15564 High_Bound => Hi));
15566 Conditional_Delay (Derived_Type, Parent_Type);
15568 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
15569 Set_Etype (Derived_Type, Implicit_Base);
15570 Set_Size_Info (Derived_Type, Parent_Type);
15572 if Unknown_RM_Size (Derived_Type) then
15573 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
15576 Set_Is_Character_Type (Derived_Type, True);
15578 if Nkind (Indic) /= N_Subtype_Indication then
15580 -- If no explicit constraint, the bounds are those
15581 -- of the parent type.
15583 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
15584 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
15585 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
15588 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
15590 -- Because the implicit base is used in the conversion of the bounds, we
15591 -- have to freeze it now. This is similar to what is done for numeric
15592 -- types, and it equally suspicious, but otherwise a non-static bound
15593 -- will have a reference to an unfrozen type, which is rejected by Gigi
15594 -- (???). This requires specific care for definition of stream
15595 -- attributes. For details, see comments at the end of
15596 -- Build_Derived_Numeric_Type.
15598 Freeze_Before (N, Implicit_Base);
15599 end Derived_Standard_Character;
15601 ------------------------------
15602 -- Derived_Type_Declaration --
15603 ------------------------------
15605 procedure Derived_Type_Declaration
15608 Is_Completion : Boolean)
15610 Parent_Type : Entity_Id;
15612 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
15613 -- Check whether the parent type is a generic formal, or derives
15614 -- directly or indirectly from one.
15616 ------------------------
15617 -- Comes_From_Generic --
15618 ------------------------
15620 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
15622 if Is_Generic_Type (Typ) then
15625 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
15628 elsif Is_Private_Type (Typ)
15629 and then Present (Full_View (Typ))
15630 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
15634 elsif Is_Generic_Actual_Type (Typ) then
15640 end Comes_From_Generic;
15644 Def : constant Node_Id := Type_Definition (N);
15645 Iface_Def : Node_Id;
15646 Indic : constant Node_Id := Subtype_Indication (Def);
15647 Extension : constant Node_Id := Record_Extension_Part (Def);
15648 Parent_Node : Node_Id;
15651 -- Start of processing for Derived_Type_Declaration
15654 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
15656 -- Ada 2005 (AI-251): In case of interface derivation check that the
15657 -- parent is also an interface.
15659 if Interface_Present (Def) then
15660 Check_SPARK_05_Restriction ("interface is not allowed", Def);
15662 if not Is_Interface (Parent_Type) then
15663 Diagnose_Interface (Indic, Parent_Type);
15666 Parent_Node := Parent (Base_Type (Parent_Type));
15667 Iface_Def := Type_Definition (Parent_Node);
15669 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
15670 -- other limited interfaces.
15672 if Limited_Present (Def) then
15673 if Limited_Present (Iface_Def) then
15676 elsif Protected_Present (Iface_Def) then
15678 ("descendant of & must be declared as a protected "
15679 & "interface", N, Parent_Type);
15681 elsif Synchronized_Present (Iface_Def) then
15683 ("descendant of & must be declared as a synchronized "
15684 & "interface", N, Parent_Type);
15686 elsif Task_Present (Iface_Def) then
15688 ("descendant of & must be declared as a task interface",
15693 ("(Ada 2005) limited interface cannot inherit from "
15694 & "non-limited interface", Indic);
15697 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
15698 -- from non-limited or limited interfaces.
15700 elsif not Protected_Present (Def)
15701 and then not Synchronized_Present (Def)
15702 and then not Task_Present (Def)
15704 if Limited_Present (Iface_Def) then
15707 elsif Protected_Present (Iface_Def) then
15709 ("descendant of & must be declared as a protected "
15710 & "interface", N, Parent_Type);
15712 elsif Synchronized_Present (Iface_Def) then
15714 ("descendant of & must be declared as a synchronized "
15715 & "interface", N, Parent_Type);
15717 elsif Task_Present (Iface_Def) then
15719 ("descendant of & must be declared as a task interface",
15728 if Is_Tagged_Type (Parent_Type)
15729 and then Is_Concurrent_Type (Parent_Type)
15730 and then not Is_Interface (Parent_Type)
15733 ("parent type of a record extension cannot be a synchronized "
15734 & "tagged type (RM 3.9.1 (3/1))", N);
15735 Set_Etype (T, Any_Type);
15739 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
15742 if Is_Tagged_Type (Parent_Type)
15743 and then Is_Non_Empty_List (Interface_List (Def))
15750 Intf := First (Interface_List (Def));
15751 while Present (Intf) loop
15752 T := Find_Type_Of_Subtype_Indic (Intf);
15754 if not Is_Interface (T) then
15755 Diagnose_Interface (Intf, T);
15757 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
15758 -- a limited type from having a nonlimited progenitor.
15760 elsif (Limited_Present (Def)
15761 or else (not Is_Interface (Parent_Type)
15762 and then Is_Limited_Type (Parent_Type)))
15763 and then not Is_Limited_Interface (T)
15766 ("progenitor interface& of limited type must be limited",
15775 if Parent_Type = Any_Type
15776 or else Etype (Parent_Type) = Any_Type
15777 or else (Is_Class_Wide_Type (Parent_Type)
15778 and then Etype (Parent_Type) = T)
15780 -- If Parent_Type is undefined or illegal, make new type into a
15781 -- subtype of Any_Type, and set a few attributes to prevent cascaded
15782 -- errors. If this is a self-definition, emit error now.
15784 if T = Parent_Type or else T = Etype (Parent_Type) then
15785 Error_Msg_N ("type cannot be used in its own definition", Indic);
15788 Set_Ekind (T, Ekind (Parent_Type));
15789 Set_Etype (T, Any_Type);
15790 Set_Scalar_Range (T, Scalar_Range (Any_Type));
15792 if Is_Tagged_Type (T)
15793 and then Is_Record_Type (T)
15795 Set_Direct_Primitive_Operations (T, New_Elmt_List);
15801 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
15802 -- an interface is special because the list of interfaces in the full
15803 -- view can be given in any order. For example:
15805 -- type A is interface;
15806 -- type B is interface and A;
15807 -- type D is new B with private;
15809 -- type D is new A and B with null record; -- 1 --
15811 -- In this case we perform the following transformation of -1-:
15813 -- type D is new B and A with null record;
15815 -- If the parent of the full-view covers the parent of the partial-view
15816 -- we have two possible cases:
15818 -- 1) They have the same parent
15819 -- 2) The parent of the full-view implements some further interfaces
15821 -- In both cases we do not need to perform the transformation. In the
15822 -- first case the source program is correct and the transformation is
15823 -- not needed; in the second case the source program does not fulfill
15824 -- the no-hidden interfaces rule (AI-396) and the error will be reported
15827 -- This transformation not only simplifies the rest of the analysis of
15828 -- this type declaration but also simplifies the correct generation of
15829 -- the object layout to the expander.
15831 if In_Private_Part (Current_Scope)
15832 and then Is_Interface (Parent_Type)
15836 Partial_View : Entity_Id;
15837 Partial_View_Parent : Entity_Id;
15838 New_Iface : Node_Id;
15841 -- Look for the associated private type declaration
15843 Partial_View := First_Entity (Current_Scope);
15845 exit when No (Partial_View)
15846 or else (Has_Private_Declaration (Partial_View)
15847 and then Full_View (Partial_View) = T);
15849 Next_Entity (Partial_View);
15852 -- If the partial view was not found then the source code has
15853 -- errors and the transformation is not needed.
15855 if Present (Partial_View) then
15856 Partial_View_Parent := Etype (Partial_View);
15858 -- If the parent of the full-view covers the parent of the
15859 -- partial-view we have nothing else to do.
15861 if Interface_Present_In_Ancestor
15862 (Parent_Type, Partial_View_Parent)
15866 -- Traverse the list of interfaces of the full-view to look
15867 -- for the parent of the partial-view and perform the tree
15871 Iface := First (Interface_List (Def));
15872 while Present (Iface) loop
15873 if Etype (Iface) = Etype (Partial_View) then
15874 Rewrite (Subtype_Indication (Def),
15875 New_Copy (Subtype_Indication
15876 (Parent (Partial_View))));
15879 Make_Identifier (Sloc (N), Chars (Parent_Type));
15880 Append (New_Iface, Interface_List (Def));
15882 -- Analyze the transformed code
15884 Derived_Type_Declaration (T, N, Is_Completion);
15895 -- Only composite types other than array types are allowed to have
15898 if Present (Discriminant_Specifications (N)) then
15899 if (Is_Elementary_Type (Parent_Type)
15901 Is_Array_Type (Parent_Type))
15902 and then not Error_Posted (N)
15905 ("elementary or array type cannot have discriminants",
15906 Defining_Identifier (First (Discriminant_Specifications (N))));
15907 Set_Has_Discriminants (T, False);
15909 -- The type is allowed to have discriminants
15912 Check_SPARK_05_Restriction ("discriminant type is not allowed", N);
15916 -- In Ada 83, a derived type defined in a package specification cannot
15917 -- be used for further derivation until the end of its visible part.
15918 -- Note that derivation in the private part of the package is allowed.
15920 if Ada_Version = Ada_83
15921 and then Is_Derived_Type (Parent_Type)
15922 and then In_Visible_Part (Scope (Parent_Type))
15924 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
15926 ("(Ada 83): premature use of type for derivation", Indic);
15930 -- Check for early use of incomplete or private type
15932 if Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
15933 Error_Msg_N ("premature derivation of incomplete type", Indic);
15936 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
15937 and then not Comes_From_Generic (Parent_Type))
15938 or else Has_Private_Component (Parent_Type)
15940 -- The ancestor type of a formal type can be incomplete, in which
15941 -- case only the operations of the partial view are available in the
15942 -- generic. Subsequent checks may be required when the full view is
15943 -- analyzed to verify that a derivation from a tagged type has an
15946 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
15949 elsif No (Underlying_Type (Parent_Type))
15950 or else Has_Private_Component (Parent_Type)
15953 ("premature derivation of derived or private type", Indic);
15955 -- Flag the type itself as being in error, this prevents some
15956 -- nasty problems with subsequent uses of the malformed type.
15958 Set_Error_Posted (T);
15960 -- Check that within the immediate scope of an untagged partial
15961 -- view it's illegal to derive from the partial view if the
15962 -- full view is tagged. (7.3(7))
15964 -- We verify that the Parent_Type is a partial view by checking
15965 -- that it is not a Full_Type_Declaration (i.e. a private type or
15966 -- private extension declaration), to distinguish a partial view
15967 -- from a derivation from a private type which also appears as
15968 -- E_Private_Type. If the parent base type is not declared in an
15969 -- enclosing scope there is no need to check.
15971 elsif Present (Full_View (Parent_Type))
15972 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
15973 and then not Is_Tagged_Type (Parent_Type)
15974 and then Is_Tagged_Type (Full_View (Parent_Type))
15975 and then In_Open_Scopes (Scope (Base_Type (Parent_Type)))
15978 ("premature derivation from type with tagged full view",
15983 -- Check that form of derivation is appropriate
15985 Taggd := Is_Tagged_Type (Parent_Type);
15987 -- Set the parent type to the class-wide type's specific type in this
15988 -- case to prevent cascading errors
15990 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
15991 Error_Msg_N ("parent type must not be a class-wide type", Indic);
15992 Set_Etype (T, Etype (Parent_Type));
15996 if Present (Extension) and then not Taggd then
15998 ("type derived from untagged type cannot have extension", Indic);
16000 elsif No (Extension) and then Taggd then
16002 -- If this declaration is within a private part (or body) of a
16003 -- generic instantiation then the derivation is allowed (the parent
16004 -- type can only appear tagged in this case if it's a generic actual
16005 -- type, since it would otherwise have been rejected in the analysis
16006 -- of the generic template).
16008 if not Is_Generic_Actual_Type (Parent_Type)
16009 or else In_Visible_Part (Scope (Parent_Type))
16011 if Is_Class_Wide_Type (Parent_Type) then
16013 ("parent type must not be a class-wide type", Indic);
16015 -- Use specific type to prevent cascaded errors.
16017 Parent_Type := Etype (Parent_Type);
16021 ("type derived from tagged type must have extension", Indic);
16026 -- AI-443: Synchronized formal derived types require a private
16027 -- extension. There is no point in checking the ancestor type or
16028 -- the progenitors since the construct is wrong to begin with.
16030 if Ada_Version >= Ada_2005
16031 and then Is_Generic_Type (T)
16032 and then Present (Original_Node (N))
16035 Decl : constant Node_Id := Original_Node (N);
16038 if Nkind (Decl) = N_Formal_Type_Declaration
16039 and then Nkind (Formal_Type_Definition (Decl)) =
16040 N_Formal_Derived_Type_Definition
16041 and then Synchronized_Present (Formal_Type_Definition (Decl))
16042 and then No (Extension)
16044 -- Avoid emitting a duplicate error message
16046 and then not Error_Posted (Indic)
16049 ("synchronized derived type must have extension", N);
16054 if Null_Exclusion_Present (Def)
16055 and then not Is_Access_Type (Parent_Type)
16057 Error_Msg_N ("null exclusion can only apply to an access type", N);
16060 -- Avoid deriving parent primitives of underlying record views
16062 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
16063 Derive_Subps => not Is_Underlying_Record_View (T));
16065 -- AI-419: The parent type of an explicitly limited derived type must
16066 -- be a limited type or a limited interface.
16068 if Limited_Present (Def) then
16069 Set_Is_Limited_Record (T);
16071 if Is_Interface (T) then
16072 Set_Is_Limited_Interface (T);
16075 if not Is_Limited_Type (Parent_Type)
16077 (not Is_Interface (Parent_Type)
16078 or else not Is_Limited_Interface (Parent_Type))
16080 -- AI05-0096: a derivation in the private part of an instance is
16081 -- legal if the generic formal is untagged limited, and the actual
16084 if Is_Generic_Actual_Type (Parent_Type)
16085 and then In_Private_Part (Current_Scope)
16088 (Generic_Parent_Type (Parent (Parent_Type)))
16094 ("parent type& of limited type must be limited",
16100 -- In SPARK, there are no derived type definitions other than type
16101 -- extensions of tagged record types.
16103 if No (Extension) then
16104 Check_SPARK_05_Restriction
16105 ("derived type is not allowed", Original_Node (N));
16107 end Derived_Type_Declaration;
16109 ------------------------
16110 -- Diagnose_Interface --
16111 ------------------------
16113 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
16115 if not Is_Interface (E) and then E /= Any_Type then
16116 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
16118 end Diagnose_Interface;
16120 ----------------------------------
16121 -- Enumeration_Type_Declaration --
16122 ----------------------------------
16124 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
16131 -- Create identifier node representing lower bound
16133 B_Node := New_Node (N_Identifier, Sloc (Def));
16134 L := First (Literals (Def));
16135 Set_Chars (B_Node, Chars (L));
16136 Set_Entity (B_Node, L);
16137 Set_Etype (B_Node, T);
16138 Set_Is_Static_Expression (B_Node, True);
16140 R_Node := New_Node (N_Range, Sloc (Def));
16141 Set_Low_Bound (R_Node, B_Node);
16143 Set_Ekind (T, E_Enumeration_Type);
16144 Set_First_Literal (T, L);
16146 Set_Is_Constrained (T);
16150 -- Loop through literals of enumeration type setting pos and rep values
16151 -- except that if the Ekind is already set, then it means the literal
16152 -- was already constructed (case of a derived type declaration and we
16153 -- should not disturb the Pos and Rep values.
16155 while Present (L) loop
16156 if Ekind (L) /= E_Enumeration_Literal then
16157 Set_Ekind (L, E_Enumeration_Literal);
16158 Set_Enumeration_Pos (L, Ev);
16159 Set_Enumeration_Rep (L, Ev);
16160 Set_Is_Known_Valid (L, True);
16164 New_Overloaded_Entity (L);
16165 Generate_Definition (L);
16166 Set_Convention (L, Convention_Intrinsic);
16168 -- Case of character literal
16170 if Nkind (L) = N_Defining_Character_Literal then
16171 Set_Is_Character_Type (T, True);
16173 -- Check violation of No_Wide_Characters
16175 if Restriction_Check_Required (No_Wide_Characters) then
16176 Get_Name_String (Chars (L));
16178 if Name_Len >= 3 and then Name_Buffer (1 .. 2) = "QW" then
16179 Check_Restriction (No_Wide_Characters, L);
16188 -- Now create a node representing upper bound
16190 B_Node := New_Node (N_Identifier, Sloc (Def));
16191 Set_Chars (B_Node, Chars (Last (Literals (Def))));
16192 Set_Entity (B_Node, Last (Literals (Def)));
16193 Set_Etype (B_Node, T);
16194 Set_Is_Static_Expression (B_Node, True);
16196 Set_High_Bound (R_Node, B_Node);
16198 -- Initialize various fields of the type. Some of this information
16199 -- may be overwritten later through rep.clauses.
16201 Set_Scalar_Range (T, R_Node);
16202 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
16203 Set_Enum_Esize (T);
16204 Set_Enum_Pos_To_Rep (T, Empty);
16206 -- Set Discard_Names if configuration pragma set, or if there is
16207 -- a parameterless pragma in the current declarative region
16209 if Global_Discard_Names or else Discard_Names (Scope (T)) then
16210 Set_Discard_Names (T);
16213 -- Process end label if there is one
16215 if Present (Def) then
16216 Process_End_Label (Def, 'e', T);
16218 end Enumeration_Type_Declaration;
16220 ---------------------------------
16221 -- Expand_To_Stored_Constraint --
16222 ---------------------------------
16224 function Expand_To_Stored_Constraint
16226 Constraint : Elist_Id) return Elist_Id
16228 Explicitly_Discriminated_Type : Entity_Id;
16229 Expansion : Elist_Id;
16230 Discriminant : Entity_Id;
16232 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
16233 -- Find the nearest type that actually specifies discriminants
16235 ---------------------------------
16236 -- Type_With_Explicit_Discrims --
16237 ---------------------------------
16239 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
16240 Typ : constant E := Base_Type (Id);
16243 if Ekind (Typ) in Incomplete_Or_Private_Kind then
16244 if Present (Full_View (Typ)) then
16245 return Type_With_Explicit_Discrims (Full_View (Typ));
16249 if Has_Discriminants (Typ) then
16254 if Etype (Typ) = Typ then
16256 elsif Has_Discriminants (Typ) then
16259 return Type_With_Explicit_Discrims (Etype (Typ));
16262 end Type_With_Explicit_Discrims;
16264 -- Start of processing for Expand_To_Stored_Constraint
16267 if No (Constraint) or else Is_Empty_Elmt_List (Constraint) then
16271 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
16273 if No (Explicitly_Discriminated_Type) then
16277 Expansion := New_Elmt_List;
16280 First_Stored_Discriminant (Explicitly_Discriminated_Type);
16281 while Present (Discriminant) loop
16283 (Get_Discriminant_Value
16284 (Discriminant, Explicitly_Discriminated_Type, Constraint),
16286 Next_Stored_Discriminant (Discriminant);
16290 end Expand_To_Stored_Constraint;
16292 ---------------------------
16293 -- Find_Hidden_Interface --
16294 ---------------------------
16296 function Find_Hidden_Interface
16298 Dest : Elist_Id) return Entity_Id
16301 Iface_Elmt : Elmt_Id;
16304 if Present (Src) and then Present (Dest) then
16305 Iface_Elmt := First_Elmt (Src);
16306 while Present (Iface_Elmt) loop
16307 Iface := Node (Iface_Elmt);
16309 if Is_Interface (Iface)
16310 and then not Contain_Interface (Iface, Dest)
16315 Next_Elmt (Iface_Elmt);
16320 end Find_Hidden_Interface;
16322 --------------------
16323 -- Find_Type_Name --
16324 --------------------
16326 function Find_Type_Name (N : Node_Id) return Entity_Id is
16327 Id : constant Entity_Id := Defining_Identifier (N);
16329 New_Id : Entity_Id;
16330 Prev_Par : Node_Id;
16332 procedure Check_Duplicate_Aspects;
16333 -- Check that aspects specified in a completion have not been specified
16334 -- already in the partial view. Type_Invariant and others can be
16335 -- specified on either view but never on both.
16337 procedure Tag_Mismatch;
16338 -- Diagnose a tagged partial view whose full view is untagged.
16339 -- We post the message on the full view, with a reference to
16340 -- the previous partial view. The partial view can be private
16341 -- or incomplete, and these are handled in a different manner,
16342 -- so we determine the position of the error message from the
16343 -- respective slocs of both.
16345 -----------------------------
16346 -- Check_Duplicate_Aspects --
16347 -----------------------------
16349 procedure Check_Duplicate_Aspects is
16350 Prev_Aspects : constant List_Id := Aspect_Specifications (Prev_Par);
16351 Full_Aspects : constant List_Id := Aspect_Specifications (N);
16352 F_Spec, P_Spec : Node_Id;
16355 if Present (Full_Aspects) then
16356 F_Spec := First (Full_Aspects);
16357 while Present (F_Spec) loop
16358 if Present (Prev_Aspects) then
16359 P_Spec := First (Prev_Aspects);
16360 while Present (P_Spec) loop
16361 if Chars (Identifier (P_Spec)) =
16362 Chars (Identifier (F_Spec))
16365 ("aspect already specified in private declaration",
16375 if Has_Discriminants (Prev)
16376 and then not Has_Unknown_Discriminants (Prev)
16377 and then Chars (Identifier (F_Spec)) =
16378 Name_Implicit_Dereference
16380 Error_Msg_N ("cannot specify aspect " &
16381 "if partial view has known discriminants", F_Spec);
16387 end Check_Duplicate_Aspects;
16393 procedure Tag_Mismatch is
16395 if Sloc (Prev) < Sloc (Id) then
16396 if Ada_Version >= Ada_2012
16397 and then Nkind (N) = N_Private_Type_Declaration
16400 ("declaration of private } must be a tagged type ", Id, Prev);
16403 ("full declaration of } must be a tagged type ", Id, Prev);
16407 if Ada_Version >= Ada_2012
16408 and then Nkind (N) = N_Private_Type_Declaration
16411 ("declaration of private } must be a tagged type ", Prev, Id);
16414 ("full declaration of } must be a tagged type ", Prev, Id);
16419 -- Start of processing for Find_Type_Name
16422 -- Find incomplete declaration, if one was given
16424 Prev := Current_Entity_In_Scope (Id);
16426 -- New type declaration
16432 -- Previous declaration exists
16435 Prev_Par := Parent (Prev);
16437 -- Error if not incomplete/private case except if previous
16438 -- declaration is implicit, etc. Enter_Name will emit error if
16441 if not Is_Incomplete_Or_Private_Type (Prev) then
16445 -- Check invalid completion of private or incomplete type
16447 elsif not Nkind_In (N, N_Full_Type_Declaration,
16448 N_Task_Type_Declaration,
16449 N_Protected_Type_Declaration)
16451 (Ada_Version < Ada_2012
16452 or else not Is_Incomplete_Type (Prev)
16453 or else not Nkind_In (N, N_Private_Type_Declaration,
16454 N_Private_Extension_Declaration))
16456 -- Completion must be a full type declarations (RM 7.3(4))
16458 Error_Msg_Sloc := Sloc (Prev);
16459 Error_Msg_NE ("invalid completion of }", Id, Prev);
16461 -- Set scope of Id to avoid cascaded errors. Entity is never
16462 -- examined again, except when saving globals in generics.
16464 Set_Scope (Id, Current_Scope);
16467 -- If this is a repeated incomplete declaration, no further
16468 -- checks are possible.
16470 if Nkind (N) = N_Incomplete_Type_Declaration then
16474 -- Case of full declaration of incomplete type
16476 elsif Ekind (Prev) = E_Incomplete_Type
16477 and then (Ada_Version < Ada_2012
16478 or else No (Full_View (Prev))
16479 or else not Is_Private_Type (Full_View (Prev)))
16481 -- Indicate that the incomplete declaration has a matching full
16482 -- declaration. The defining occurrence of the incomplete
16483 -- declaration remains the visible one, and the procedure
16484 -- Get_Full_View dereferences it whenever the type is used.
16486 if Present (Full_View (Prev)) then
16487 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
16490 Set_Full_View (Prev, Id);
16491 Append_Entity (Id, Current_Scope);
16492 Set_Is_Public (Id, Is_Public (Prev));
16493 Set_Is_Internal (Id);
16496 -- If the incomplete view is tagged, a class_wide type has been
16497 -- created already. Use it for the private type as well, in order
16498 -- to prevent multiple incompatible class-wide types that may be
16499 -- created for self-referential anonymous access components.
16501 if Is_Tagged_Type (Prev)
16502 and then Present (Class_Wide_Type (Prev))
16504 Set_Ekind (Id, Ekind (Prev)); -- will be reset later
16505 Set_Class_Wide_Type (Id, Class_Wide_Type (Prev));
16507 -- The type of the classwide type is the current Id. Previously
16508 -- this was not done for private declarations because of order-
16509 -- of elaboration issues in the back-end, but gigi now handles
16512 Set_Etype (Class_Wide_Type (Id), Id);
16515 -- Case of full declaration of private type
16518 -- If the private type was a completion of an incomplete type then
16519 -- update Prev to reference the private type
16521 if Ada_Version >= Ada_2012
16522 and then Ekind (Prev) = E_Incomplete_Type
16523 and then Present (Full_View (Prev))
16524 and then Is_Private_Type (Full_View (Prev))
16526 Prev := Full_View (Prev);
16527 Prev_Par := Parent (Prev);
16530 if Nkind (N) = N_Full_Type_Declaration
16532 (Type_Definition (N), N_Record_Definition,
16533 N_Derived_Type_Definition)
16534 and then Interface_Present (Type_Definition (N))
16537 ("completion of private type cannot be an interface", N);
16540 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
16541 if Etype (Prev) /= Prev then
16543 -- Prev is a private subtype or a derived type, and needs
16546 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
16549 elsif Ekind (Prev) = E_Private_Type
16550 and then Nkind_In (N, N_Task_Type_Declaration,
16551 N_Protected_Type_Declaration)
16554 ("completion of nonlimited type cannot be limited", N);
16556 elsif Ekind (Prev) = E_Record_Type_With_Private
16557 and then Nkind_In (N, N_Task_Type_Declaration,
16558 N_Protected_Type_Declaration)
16560 if not Is_Limited_Record (Prev) then
16562 ("completion of nonlimited type cannot be limited", N);
16564 elsif No (Interface_List (N)) then
16566 ("completion of tagged private type must be tagged",
16571 -- Ada 2005 (AI-251): Private extension declaration of a task
16572 -- type or a protected type. This case arises when covering
16573 -- interface types.
16575 elsif Nkind_In (N, N_Task_Type_Declaration,
16576 N_Protected_Type_Declaration)
16580 elsif Nkind (N) /= N_Full_Type_Declaration
16581 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
16584 ("full view of private extension must be an extension", N);
16586 elsif not (Abstract_Present (Parent (Prev)))
16587 and then Abstract_Present (Type_Definition (N))
16590 ("full view of non-abstract extension cannot be abstract", N);
16593 if not In_Private_Part (Current_Scope) then
16595 ("declaration of full view must appear in private part", N);
16598 if Ada_Version >= Ada_2012 then
16599 Check_Duplicate_Aspects;
16602 Copy_And_Swap (Prev, Id);
16603 Set_Has_Private_Declaration (Prev);
16604 Set_Has_Private_Declaration (Id);
16606 -- AI12-0133: Indicate whether we have a partial view with
16607 -- unknown discriminants, in which case initialization of objects
16608 -- of the type do not receive an invariant check.
16610 Set_Partial_View_Has_Unknown_Discr
16611 (Prev, Has_Unknown_Discriminants (Id));
16613 -- Preserve aspect and iterator flags that may have been set on
16614 -- the partial view.
16616 Set_Has_Delayed_Aspects (Prev, Has_Delayed_Aspects (Id));
16617 Set_Has_Implicit_Dereference (Prev, Has_Implicit_Dereference (Id));
16619 -- If no error, propagate freeze_node from private to full view.
16620 -- It may have been generated for an early operational item.
16622 if Present (Freeze_Node (Id))
16623 and then Serious_Errors_Detected = 0
16624 and then No (Full_View (Id))
16626 Set_Freeze_Node (Prev, Freeze_Node (Id));
16627 Set_Freeze_Node (Id, Empty);
16628 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
16631 Set_Full_View (Id, Prev);
16635 -- Verify that full declaration conforms to partial one
16637 if Is_Incomplete_Or_Private_Type (Prev)
16638 and then Present (Discriminant_Specifications (Prev_Par))
16640 if Present (Discriminant_Specifications (N)) then
16641 if Ekind (Prev) = E_Incomplete_Type then
16642 Check_Discriminant_Conformance (N, Prev, Prev);
16644 Check_Discriminant_Conformance (N, Prev, Id);
16649 ("missing discriminants in full type declaration", N);
16651 -- To avoid cascaded errors on subsequent use, share the
16652 -- discriminants of the partial view.
16654 Set_Discriminant_Specifications (N,
16655 Discriminant_Specifications (Prev_Par));
16659 -- A prior untagged partial view can have an associated class-wide
16660 -- type due to use of the class attribute, and in this case the full
16661 -- type must also be tagged. This Ada 95 usage is deprecated in favor
16662 -- of incomplete tagged declarations, but we check for it.
16665 and then (Is_Tagged_Type (Prev)
16666 or else Present (Class_Wide_Type (Prev)))
16668 -- Ada 2012 (AI05-0162): A private type may be the completion of
16669 -- an incomplete type.
16671 if Ada_Version >= Ada_2012
16672 and then Is_Incomplete_Type (Prev)
16673 and then Nkind_In (N, N_Private_Type_Declaration,
16674 N_Private_Extension_Declaration)
16676 -- No need to check private extensions since they are tagged
16678 if Nkind (N) = N_Private_Type_Declaration
16679 and then not Tagged_Present (N)
16684 -- The full declaration is either a tagged type (including
16685 -- a synchronized type that implements interfaces) or a
16686 -- type extension, otherwise this is an error.
16688 elsif Nkind_In (N, N_Task_Type_Declaration,
16689 N_Protected_Type_Declaration)
16691 if No (Interface_List (N)) and then not Error_Posted (N) then
16695 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
16697 -- Indicate that the previous declaration (tagged incomplete
16698 -- or private declaration) requires the same on the full one.
16700 if not Tagged_Present (Type_Definition (N)) then
16702 Set_Is_Tagged_Type (Id);
16705 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
16706 if No (Record_Extension_Part (Type_Definition (N))) then
16708 ("full declaration of } must be a record extension",
16711 -- Set some attributes to produce a usable full view
16713 Set_Is_Tagged_Type (Id);
16722 and then Nkind (Parent (Prev)) = N_Incomplete_Type_Declaration
16723 and then Present (Premature_Use (Parent (Prev)))
16725 Error_Msg_Sloc := Sloc (N);
16727 ("\full declaration #", Premature_Use (Parent (Prev)));
16732 end Find_Type_Name;
16734 -------------------------
16735 -- Find_Type_Of_Object --
16736 -------------------------
16738 function Find_Type_Of_Object
16739 (Obj_Def : Node_Id;
16740 Related_Nod : Node_Id) return Entity_Id
16742 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
16743 P : Node_Id := Parent (Obj_Def);
16748 -- If the parent is a component_definition node we climb to the
16749 -- component_declaration node
16751 if Nkind (P) = N_Component_Definition then
16755 -- Case of an anonymous array subtype
16757 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
16758 N_Unconstrained_Array_Definition)
16761 Array_Type_Declaration (T, Obj_Def);
16763 -- Create an explicit subtype whenever possible
16765 elsif Nkind (P) /= N_Component_Declaration
16766 and then Def_Kind = N_Subtype_Indication
16768 -- Base name of subtype on object name, which will be unique in
16769 -- the current scope.
16771 -- If this is a duplicate declaration, return base type, to avoid
16772 -- generating duplicate anonymous types.
16774 if Error_Posted (P) then
16775 Analyze (Subtype_Mark (Obj_Def));
16776 return Entity (Subtype_Mark (Obj_Def));
16781 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
16783 T := Make_Defining_Identifier (Sloc (P), Nam);
16785 Insert_Action (Obj_Def,
16786 Make_Subtype_Declaration (Sloc (P),
16787 Defining_Identifier => T,
16788 Subtype_Indication => Relocate_Node (Obj_Def)));
16790 -- This subtype may need freezing, and this will not be done
16791 -- automatically if the object declaration is not in declarative
16792 -- part. Since this is an object declaration, the type cannot always
16793 -- be frozen here. Deferred constants do not freeze their type
16794 -- (which often enough will be private).
16796 if Nkind (P) = N_Object_Declaration
16797 and then Constant_Present (P)
16798 and then No (Expression (P))
16802 -- Here we freeze the base type of object type to catch premature use
16803 -- of discriminated private type without a full view.
16806 Insert_Actions (Obj_Def, Freeze_Entity (Base_Type (T), P));
16809 -- Ada 2005 AI-406: the object definition in an object declaration
16810 -- can be an access definition.
16812 elsif Def_Kind = N_Access_Definition then
16813 T := Access_Definition (Related_Nod, Obj_Def);
16815 Set_Is_Local_Anonymous_Access
16817 V => (Ada_Version < Ada_2012)
16818 or else (Nkind (P) /= N_Object_Declaration)
16819 or else Is_Library_Level_Entity (Defining_Identifier (P)));
16821 -- Otherwise, the object definition is just a subtype_mark
16824 T := Process_Subtype (Obj_Def, Related_Nod);
16826 -- If expansion is disabled an object definition that is an aggregate
16827 -- will not get expanded and may lead to scoping problems in the back
16828 -- end, if the object is referenced in an inner scope. In that case
16829 -- create an itype reference for the object definition now. This
16830 -- may be redundant in some cases, but harmless.
16833 and then Nkind (Related_Nod) = N_Object_Declaration
16836 Build_Itype_Reference (T, Related_Nod);
16841 end Find_Type_Of_Object;
16843 --------------------------------
16844 -- Find_Type_Of_Subtype_Indic --
16845 --------------------------------
16847 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
16851 -- Case of subtype mark with a constraint
16853 if Nkind (S) = N_Subtype_Indication then
16854 Find_Type (Subtype_Mark (S));
16855 Typ := Entity (Subtype_Mark (S));
16858 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
16861 ("incorrect constraint for this kind of type", Constraint (S));
16862 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
16865 -- Otherwise we have a subtype mark without a constraint
16867 elsif Error_Posted (S) then
16868 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
16876 -- Check No_Wide_Characters restriction
16878 Check_Wide_Character_Restriction (Typ, S);
16881 end Find_Type_Of_Subtype_Indic;
16883 -------------------------------------
16884 -- Floating_Point_Type_Declaration --
16885 -------------------------------------
16887 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
16888 Digs : constant Node_Id := Digits_Expression (Def);
16889 Max_Digs_Val : constant Uint := Digits_Value (Standard_Long_Long_Float);
16891 Base_Typ : Entity_Id;
16892 Implicit_Base : Entity_Id;
16895 function Can_Derive_From (E : Entity_Id) return Boolean;
16896 -- Find if given digits value, and possibly a specified range, allows
16897 -- derivation from specified type
16899 function Find_Base_Type return Entity_Id;
16900 -- Find a predefined base type that Def can derive from, or generate
16901 -- an error and substitute Long_Long_Float if none exists.
16903 ---------------------
16904 -- Can_Derive_From --
16905 ---------------------
16907 function Can_Derive_From (E : Entity_Id) return Boolean is
16908 Spec : constant Entity_Id := Real_Range_Specification (Def);
16911 -- Check specified "digits" constraint
16913 if Digs_Val > Digits_Value (E) then
16917 -- Check for matching range, if specified
16919 if Present (Spec) then
16920 if Expr_Value_R (Type_Low_Bound (E)) >
16921 Expr_Value_R (Low_Bound (Spec))
16926 if Expr_Value_R (Type_High_Bound (E)) <
16927 Expr_Value_R (High_Bound (Spec))
16934 end Can_Derive_From;
16936 --------------------
16937 -- Find_Base_Type --
16938 --------------------
16940 function Find_Base_Type return Entity_Id is
16941 Choice : Elmt_Id := First_Elmt (Predefined_Float_Types);
16944 -- Iterate over the predefined types in order, returning the first
16945 -- one that Def can derive from.
16947 while Present (Choice) loop
16948 if Can_Derive_From (Node (Choice)) then
16949 return Node (Choice);
16952 Next_Elmt (Choice);
16955 -- If we can't derive from any existing type, use Long_Long_Float
16956 -- and give appropriate message explaining the problem.
16958 if Digs_Val > Max_Digs_Val then
16959 -- It might be the case that there is a type with the requested
16960 -- range, just not the combination of digits and range.
16963 ("no predefined type has requested range and precision",
16964 Real_Range_Specification (Def));
16968 ("range too large for any predefined type",
16969 Real_Range_Specification (Def));
16972 return Standard_Long_Long_Float;
16973 end Find_Base_Type;
16975 -- Start of processing for Floating_Point_Type_Declaration
16978 Check_Restriction (No_Floating_Point, Def);
16980 -- Create an implicit base type
16983 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
16985 -- Analyze and verify digits value
16987 Analyze_And_Resolve (Digs, Any_Integer);
16988 Check_Digits_Expression (Digs);
16989 Digs_Val := Expr_Value (Digs);
16991 -- Process possible range spec and find correct type to derive from
16993 Process_Real_Range_Specification (Def);
16995 -- Check that requested number of digits is not too high.
16997 if Digs_Val > Max_Digs_Val then
16999 -- The check for Max_Base_Digits may be somewhat expensive, as it
17000 -- requires reading System, so only do it when necessary.
17003 Max_Base_Digits : constant Uint :=
17006 (Parent (RTE (RE_Max_Base_Digits))));
17009 if Digs_Val > Max_Base_Digits then
17010 Error_Msg_Uint_1 := Max_Base_Digits;
17011 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
17013 elsif No (Real_Range_Specification (Def)) then
17014 Error_Msg_Uint_1 := Max_Digs_Val;
17015 Error_Msg_N ("types with more than ^ digits need range spec "
17016 & "(RM 3.5.7(6))", Digs);
17021 -- Find a suitable type to derive from or complain and use a substitute
17023 Base_Typ := Find_Base_Type;
17025 -- If there are bounds given in the declaration use them as the bounds
17026 -- of the type, otherwise use the bounds of the predefined base type
17027 -- that was chosen based on the Digits value.
17029 if Present (Real_Range_Specification (Def)) then
17030 Set_Scalar_Range (T, Real_Range_Specification (Def));
17031 Set_Is_Constrained (T);
17033 -- The bounds of this range must be converted to machine numbers
17034 -- in accordance with RM 4.9(38).
17036 Bound := Type_Low_Bound (T);
17038 if Nkind (Bound) = N_Real_Literal then
17040 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
17041 Set_Is_Machine_Number (Bound);
17044 Bound := Type_High_Bound (T);
17046 if Nkind (Bound) = N_Real_Literal then
17048 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
17049 Set_Is_Machine_Number (Bound);
17053 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
17056 -- Complete definition of implicit base and declared first subtype. The
17057 -- inheritance of the rep item chain ensures that SPARK-related pragmas
17058 -- are not clobbered when the floating point type acts as a full view of
17061 Set_Etype (Implicit_Base, Base_Typ);
17062 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
17063 Set_Size_Info (Implicit_Base, Base_Typ);
17064 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
17065 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
17066 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
17067 Set_Float_Rep (Implicit_Base, Float_Rep (Base_Typ));
17069 Set_Ekind (T, E_Floating_Point_Subtype);
17070 Set_Etype (T, Implicit_Base);
17071 Set_Size_Info (T, Implicit_Base);
17072 Set_RM_Size (T, RM_Size (Implicit_Base));
17073 Inherit_Rep_Item_Chain (T, Implicit_Base);
17074 Set_Digits_Value (T, Digs_Val);
17075 end Floating_Point_Type_Declaration;
17077 ----------------------------
17078 -- Get_Discriminant_Value --
17079 ----------------------------
17081 -- This is the situation:
17083 -- There is a non-derived type
17085 -- type T0 (Dx, Dy, Dz...)
17087 -- There are zero or more levels of derivation, with each derivation
17088 -- either purely inheriting the discriminants, or defining its own.
17090 -- type Ti is new Ti-1
17092 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
17094 -- subtype Ti is ...
17096 -- The subtype issue is avoided by the use of Original_Record_Component,
17097 -- and the fact that derived subtypes also derive the constraints.
17099 -- This chain leads back from
17101 -- Typ_For_Constraint
17103 -- Typ_For_Constraint has discriminants, and the value for each
17104 -- discriminant is given by its corresponding Elmt of Constraints.
17106 -- Discriminant is some discriminant in this hierarchy
17108 -- We need to return its value
17110 -- We do this by recursively searching each level, and looking for
17111 -- Discriminant. Once we get to the bottom, we start backing up
17112 -- returning the value for it which may in turn be a discriminant
17113 -- further up, so on the backup we continue the substitution.
17115 function Get_Discriminant_Value
17116 (Discriminant : Entity_Id;
17117 Typ_For_Constraint : Entity_Id;
17118 Constraint : Elist_Id) return Node_Id
17120 function Root_Corresponding_Discriminant
17121 (Discr : Entity_Id) return Entity_Id;
17122 -- Given a discriminant, traverse the chain of inherited discriminants
17123 -- and return the topmost discriminant.
17125 function Search_Derivation_Levels
17127 Discrim_Values : Elist_Id;
17128 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
17129 -- This is the routine that performs the recursive search of levels
17130 -- as described above.
17132 -------------------------------------
17133 -- Root_Corresponding_Discriminant --
17134 -------------------------------------
17136 function Root_Corresponding_Discriminant
17137 (Discr : Entity_Id) return Entity_Id
17143 while Present (Corresponding_Discriminant (D)) loop
17144 D := Corresponding_Discriminant (D);
17148 end Root_Corresponding_Discriminant;
17150 ------------------------------
17151 -- Search_Derivation_Levels --
17152 ------------------------------
17154 function Search_Derivation_Levels
17156 Discrim_Values : Elist_Id;
17157 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
17161 Result : Node_Or_Entity_Id;
17162 Result_Entity : Node_Id;
17165 -- If inappropriate type, return Error, this happens only in
17166 -- cascaded error situations, and we want to avoid a blow up.
17168 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
17172 -- Look deeper if possible. Use Stored_Constraints only for
17173 -- untagged types. For tagged types use the given constraint.
17174 -- This asymmetry needs explanation???
17176 if not Stored_Discrim_Values
17177 and then Present (Stored_Constraint (Ti))
17178 and then not Is_Tagged_Type (Ti)
17181 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
17184 Td : constant Entity_Id := Etype (Ti);
17188 Result := Discriminant;
17191 if Present (Stored_Constraint (Ti)) then
17193 Search_Derivation_Levels
17194 (Td, Stored_Constraint (Ti), True);
17197 Search_Derivation_Levels
17198 (Td, Discrim_Values, Stored_Discrim_Values);
17204 -- Extra underlying places to search, if not found above. For
17205 -- concurrent types, the relevant discriminant appears in the
17206 -- corresponding record. For a type derived from a private type
17207 -- without discriminant, the full view inherits the discriminants
17208 -- of the full view of the parent.
17210 if Result = Discriminant then
17211 if Is_Concurrent_Type (Ti)
17212 and then Present (Corresponding_Record_Type (Ti))
17215 Search_Derivation_Levels (
17216 Corresponding_Record_Type (Ti),
17218 Stored_Discrim_Values);
17220 elsif Is_Private_Type (Ti)
17221 and then not Has_Discriminants (Ti)
17222 and then Present (Full_View (Ti))
17223 and then Etype (Full_View (Ti)) /= Ti
17226 Search_Derivation_Levels (
17229 Stored_Discrim_Values);
17233 -- If Result is not a (reference to a) discriminant, return it,
17234 -- otherwise set Result_Entity to the discriminant.
17236 if Nkind (Result) = N_Defining_Identifier then
17237 pragma Assert (Result = Discriminant);
17238 Result_Entity := Result;
17241 if not Denotes_Discriminant (Result) then
17245 Result_Entity := Entity (Result);
17248 -- See if this level of derivation actually has discriminants because
17249 -- tagged derivations can add them, hence the lower levels need not
17252 if not Has_Discriminants (Ti) then
17256 -- Scan Ti's discriminants for Result_Entity, and return its
17257 -- corresponding value, if any.
17259 Result_Entity := Original_Record_Component (Result_Entity);
17261 Assoc := First_Elmt (Discrim_Values);
17263 if Stored_Discrim_Values then
17264 Disc := First_Stored_Discriminant (Ti);
17266 Disc := First_Discriminant (Ti);
17269 while Present (Disc) loop
17270 pragma Assert (Present (Assoc));
17272 if Original_Record_Component (Disc) = Result_Entity then
17273 return Node (Assoc);
17278 if Stored_Discrim_Values then
17279 Next_Stored_Discriminant (Disc);
17281 Next_Discriminant (Disc);
17285 -- Could not find it
17288 end Search_Derivation_Levels;
17292 Result : Node_Or_Entity_Id;
17294 -- Start of processing for Get_Discriminant_Value
17297 -- ??? This routine is a gigantic mess and will be deleted. For the
17298 -- time being just test for the trivial case before calling recurse.
17300 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
17306 D := First_Discriminant (Typ_For_Constraint);
17307 E := First_Elmt (Constraint);
17308 while Present (D) loop
17309 if Chars (D) = Chars (Discriminant) then
17313 Next_Discriminant (D);
17319 Result := Search_Derivation_Levels
17320 (Typ_For_Constraint, Constraint, False);
17322 -- ??? hack to disappear when this routine is gone
17324 if Nkind (Result) = N_Defining_Identifier then
17330 D := First_Discriminant (Typ_For_Constraint);
17331 E := First_Elmt (Constraint);
17332 while Present (D) loop
17333 if Root_Corresponding_Discriminant (D) = Discriminant then
17337 Next_Discriminant (D);
17343 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
17345 end Get_Discriminant_Value;
17347 --------------------------
17348 -- Has_Range_Constraint --
17349 --------------------------
17351 function Has_Range_Constraint (N : Node_Id) return Boolean is
17352 C : constant Node_Id := Constraint (N);
17355 if Nkind (C) = N_Range_Constraint then
17358 elsif Nkind (C) = N_Digits_Constraint then
17360 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
17361 or else Present (Range_Constraint (C));
17363 elsif Nkind (C) = N_Delta_Constraint then
17364 return Present (Range_Constraint (C));
17369 end Has_Range_Constraint;
17371 ------------------------
17372 -- Inherit_Components --
17373 ------------------------
17375 function Inherit_Components
17377 Parent_Base : Entity_Id;
17378 Derived_Base : Entity_Id;
17379 Is_Tagged : Boolean;
17380 Inherit_Discr : Boolean;
17381 Discs : Elist_Id) return Elist_Id
17383 Assoc_List : constant Elist_Id := New_Elmt_List;
17385 procedure Inherit_Component
17386 (Old_C : Entity_Id;
17387 Plain_Discrim : Boolean := False;
17388 Stored_Discrim : Boolean := False);
17389 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
17390 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
17391 -- True, Old_C is a stored discriminant. If they are both false then
17392 -- Old_C is a regular component.
17394 -----------------------
17395 -- Inherit_Component --
17396 -----------------------
17398 procedure Inherit_Component
17399 (Old_C : Entity_Id;
17400 Plain_Discrim : Boolean := False;
17401 Stored_Discrim : Boolean := False)
17403 procedure Set_Anonymous_Type (Id : Entity_Id);
17404 -- Id denotes the entity of an access discriminant or anonymous
17405 -- access component. Set the type of Id to either the same type of
17406 -- Old_C or create a new one depending on whether the parent and
17407 -- the child types are in the same scope.
17409 ------------------------
17410 -- Set_Anonymous_Type --
17411 ------------------------
17413 procedure Set_Anonymous_Type (Id : Entity_Id) is
17414 Old_Typ : constant Entity_Id := Etype (Old_C);
17417 if Scope (Parent_Base) = Scope (Derived_Base) then
17418 Set_Etype (Id, Old_Typ);
17420 -- The parent and the derived type are in two different scopes.
17421 -- Reuse the type of the original discriminant / component by
17422 -- copying it in order to preserve all attributes.
17426 Typ : constant Entity_Id := New_Copy (Old_Typ);
17429 Set_Etype (Id, Typ);
17431 -- Since we do not generate component declarations for
17432 -- inherited components, associate the itype with the
17435 Set_Associated_Node_For_Itype (Typ, Parent (Derived_Base));
17436 Set_Scope (Typ, Derived_Base);
17439 end Set_Anonymous_Type;
17441 -- Local variables and constants
17443 New_C : constant Entity_Id := New_Copy (Old_C);
17445 Corr_Discrim : Entity_Id;
17446 Discrim : Entity_Id;
17448 -- Start of processing for Inherit_Component
17451 pragma Assert (not Is_Tagged or not Stored_Discrim);
17453 Set_Parent (New_C, Parent (Old_C));
17455 -- Regular discriminants and components must be inserted in the scope
17456 -- of the Derived_Base. Do it here.
17458 if not Stored_Discrim then
17459 Enter_Name (New_C);
17462 -- For tagged types the Original_Record_Component must point to
17463 -- whatever this field was pointing to in the parent type. This has
17464 -- already been achieved by the call to New_Copy above.
17466 if not Is_Tagged then
17467 Set_Original_Record_Component (New_C, New_C);
17470 -- Set the proper type of an access discriminant
17472 if Ekind (New_C) = E_Discriminant
17473 and then Ekind (Etype (New_C)) = E_Anonymous_Access_Type
17475 Set_Anonymous_Type (New_C);
17478 -- If we have inherited a component then see if its Etype contains
17479 -- references to Parent_Base discriminants. In this case, replace
17480 -- these references with the constraints given in Discs. We do not
17481 -- do this for the partial view of private types because this is
17482 -- not needed (only the components of the full view will be used
17483 -- for code generation) and cause problem. We also avoid this
17484 -- transformation in some error situations.
17486 if Ekind (New_C) = E_Component then
17488 -- Set the proper type of an anonymous access component
17490 if Ekind (Etype (New_C)) = E_Anonymous_Access_Type then
17491 Set_Anonymous_Type (New_C);
17493 elsif (Is_Private_Type (Derived_Base)
17494 and then not Is_Generic_Type (Derived_Base))
17495 or else (Is_Empty_Elmt_List (Discs)
17496 and then not Expander_Active)
17498 Set_Etype (New_C, Etype (Old_C));
17501 -- The current component introduces a circularity of the
17504 -- limited with Pack_2;
17505 -- package Pack_1 is
17506 -- type T_1 is tagged record
17507 -- Comp : access Pack_2.T_2;
17513 -- package Pack_2 is
17514 -- type T_2 is new Pack_1.T_1 with ...;
17519 Constrain_Component_Type
17520 (Old_C, Derived_Base, N, Parent_Base, Discs));
17524 -- In derived tagged types it is illegal to reference a non
17525 -- discriminant component in the parent type. To catch this, mark
17526 -- these components with an Ekind of E_Void. This will be reset in
17527 -- Record_Type_Definition after processing the record extension of
17528 -- the derived type.
17530 -- If the declaration is a private extension, there is no further
17531 -- record extension to process, and the components retain their
17532 -- current kind, because they are visible at this point.
17534 if Is_Tagged and then Ekind (New_C) = E_Component
17535 and then Nkind (N) /= N_Private_Extension_Declaration
17537 Set_Ekind (New_C, E_Void);
17540 if Plain_Discrim then
17541 Set_Corresponding_Discriminant (New_C, Old_C);
17542 Build_Discriminal (New_C);
17544 -- If we are explicitly inheriting a stored discriminant it will be
17545 -- completely hidden.
17547 elsif Stored_Discrim then
17548 Set_Corresponding_Discriminant (New_C, Empty);
17549 Set_Discriminal (New_C, Empty);
17550 Set_Is_Completely_Hidden (New_C);
17552 -- Set the Original_Record_Component of each discriminant in the
17553 -- derived base to point to the corresponding stored that we just
17556 Discrim := First_Discriminant (Derived_Base);
17557 while Present (Discrim) loop
17558 Corr_Discrim := Corresponding_Discriminant (Discrim);
17560 -- Corr_Discrim could be missing in an error situation
17562 if Present (Corr_Discrim)
17563 and then Original_Record_Component (Corr_Discrim) = Old_C
17565 Set_Original_Record_Component (Discrim, New_C);
17568 Next_Discriminant (Discrim);
17571 Append_Entity (New_C, Derived_Base);
17574 if not Is_Tagged then
17575 Append_Elmt (Old_C, Assoc_List);
17576 Append_Elmt (New_C, Assoc_List);
17578 end Inherit_Component;
17580 -- Variables local to Inherit_Component
17582 Loc : constant Source_Ptr := Sloc (N);
17584 Parent_Discrim : Entity_Id;
17585 Stored_Discrim : Entity_Id;
17587 Component : Entity_Id;
17589 -- Start of processing for Inherit_Components
17592 if not Is_Tagged then
17593 Append_Elmt (Parent_Base, Assoc_List);
17594 Append_Elmt (Derived_Base, Assoc_List);
17597 -- Inherit parent discriminants if needed
17599 if Inherit_Discr then
17600 Parent_Discrim := First_Discriminant (Parent_Base);
17601 while Present (Parent_Discrim) loop
17602 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
17603 Next_Discriminant (Parent_Discrim);
17607 -- Create explicit stored discrims for untagged types when necessary
17609 if not Has_Unknown_Discriminants (Derived_Base)
17610 and then Has_Discriminants (Parent_Base)
17611 and then not Is_Tagged
17614 or else First_Discriminant (Parent_Base) /=
17615 First_Stored_Discriminant (Parent_Base))
17617 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
17618 while Present (Stored_Discrim) loop
17619 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
17620 Next_Stored_Discriminant (Stored_Discrim);
17624 -- See if we can apply the second transformation for derived types, as
17625 -- explained in point 6. in the comments above Build_Derived_Record_Type
17626 -- This is achieved by appending Derived_Base discriminants into Discs,
17627 -- which has the side effect of returning a non empty Discs list to the
17628 -- caller of Inherit_Components, which is what we want. This must be
17629 -- done for private derived types if there are explicit stored
17630 -- discriminants, to ensure that we can retrieve the values of the
17631 -- constraints provided in the ancestors.
17634 and then Is_Empty_Elmt_List (Discs)
17635 and then Present (First_Discriminant (Derived_Base))
17637 (not Is_Private_Type (Derived_Base)
17638 or else Is_Completely_Hidden
17639 (First_Stored_Discriminant (Derived_Base))
17640 or else Is_Generic_Type (Derived_Base))
17642 D := First_Discriminant (Derived_Base);
17643 while Present (D) loop
17644 Append_Elmt (New_Occurrence_Of (D, Loc), Discs);
17645 Next_Discriminant (D);
17649 -- Finally, inherit non-discriminant components unless they are not
17650 -- visible because defined or inherited from the full view of the
17651 -- parent. Don't inherit the _parent field of the parent type.
17653 Component := First_Entity (Parent_Base);
17654 while Present (Component) loop
17656 -- Ada 2005 (AI-251): Do not inherit components associated with
17657 -- secondary tags of the parent.
17659 if Ekind (Component) = E_Component
17660 and then Present (Related_Type (Component))
17664 elsif Ekind (Component) /= E_Component
17665 or else Chars (Component) = Name_uParent
17669 -- If the derived type is within the parent type's declarative
17670 -- region, then the components can still be inherited even though
17671 -- they aren't visible at this point. This can occur for cases
17672 -- such as within public child units where the components must
17673 -- become visible upon entering the child unit's private part.
17675 elsif not Is_Visible_Component (Component)
17676 and then not In_Open_Scopes (Scope (Parent_Base))
17680 elsif Ekind_In (Derived_Base, E_Private_Type,
17681 E_Limited_Private_Type)
17686 Inherit_Component (Component);
17689 Next_Entity (Component);
17692 -- For tagged derived types, inherited discriminants cannot be used in
17693 -- component declarations of the record extension part. To achieve this
17694 -- we mark the inherited discriminants as not visible.
17696 if Is_Tagged and then Inherit_Discr then
17697 D := First_Discriminant (Derived_Base);
17698 while Present (D) loop
17699 Set_Is_Immediately_Visible (D, False);
17700 Next_Discriminant (D);
17705 end Inherit_Components;
17707 -----------------------------
17708 -- Inherit_Predicate_Flags --
17709 -----------------------------
17711 procedure Inherit_Predicate_Flags (Subt, Par : Entity_Id) is
17713 Set_Has_Predicates (Subt, Has_Predicates (Par));
17714 Set_Has_Static_Predicate_Aspect
17715 (Subt, Has_Static_Predicate_Aspect (Par));
17716 Set_Has_Dynamic_Predicate_Aspect
17717 (Subt, Has_Dynamic_Predicate_Aspect (Par));
17718 end Inherit_Predicate_Flags;
17720 ----------------------
17721 -- Is_EVF_Procedure --
17722 ----------------------
17724 function Is_EVF_Procedure (Subp : Entity_Id) return Boolean is
17725 Formal : Entity_Id;
17728 -- Examine the formals of an Extensions_Visible False procedure looking
17729 -- for a controlling OUT parameter.
17731 if Ekind (Subp) = E_Procedure
17732 and then Extensions_Visible_Status (Subp) = Extensions_Visible_False
17734 Formal := First_Formal (Subp);
17735 while Present (Formal) loop
17736 if Ekind (Formal) = E_Out_Parameter
17737 and then Is_Controlling_Formal (Formal)
17742 Next_Formal (Formal);
17747 end Is_EVF_Procedure;
17749 -----------------------
17750 -- Is_Null_Extension --
17751 -----------------------
17753 function Is_Null_Extension (T : Entity_Id) return Boolean is
17754 Type_Decl : constant Node_Id := Parent (Base_Type (T));
17755 Comp_List : Node_Id;
17759 if Nkind (Type_Decl) /= N_Full_Type_Declaration
17760 or else not Is_Tagged_Type (T)
17761 or else Nkind (Type_Definition (Type_Decl)) /=
17762 N_Derived_Type_Definition
17763 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
17769 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
17771 if Present (Discriminant_Specifications (Type_Decl)) then
17774 elsif Present (Comp_List)
17775 and then Is_Non_Empty_List (Component_Items (Comp_List))
17777 Comp := First (Component_Items (Comp_List));
17779 -- Only user-defined components are relevant. The component list
17780 -- may also contain a parent component and internal components
17781 -- corresponding to secondary tags, but these do not determine
17782 -- whether this is a null extension.
17784 while Present (Comp) loop
17785 if Comes_From_Source (Comp) then
17797 end Is_Null_Extension;
17799 ------------------------------
17800 -- Is_Valid_Constraint_Kind --
17801 ------------------------------
17803 function Is_Valid_Constraint_Kind
17804 (T_Kind : Type_Kind;
17805 Constraint_Kind : Node_Kind) return Boolean
17809 when Enumeration_Kind |
17811 return Constraint_Kind = N_Range_Constraint;
17813 when Decimal_Fixed_Point_Kind =>
17814 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
17815 N_Range_Constraint);
17817 when Ordinary_Fixed_Point_Kind =>
17818 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
17819 N_Range_Constraint);
17822 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
17823 N_Range_Constraint);
17830 E_Incomplete_Type |
17833 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
17836 return True; -- Error will be detected later
17838 end Is_Valid_Constraint_Kind;
17840 --------------------------
17841 -- Is_Visible_Component --
17842 --------------------------
17844 function Is_Visible_Component
17846 N : Node_Id := Empty) return Boolean
17848 Original_Comp : Entity_Id := Empty;
17849 Original_Type : Entity_Id;
17850 Type_Scope : Entity_Id;
17852 function Is_Local_Type (Typ : Entity_Id) return Boolean;
17853 -- Check whether parent type of inherited component is declared locally,
17854 -- possibly within a nested package or instance. The current scope is
17855 -- the derived record itself.
17857 -------------------
17858 -- Is_Local_Type --
17859 -------------------
17861 function Is_Local_Type (Typ : Entity_Id) return Boolean is
17865 Scop := Scope (Typ);
17866 while Present (Scop)
17867 and then Scop /= Standard_Standard
17869 if Scop = Scope (Current_Scope) then
17873 Scop := Scope (Scop);
17879 -- Start of processing for Is_Visible_Component
17882 if Ekind_In (C, E_Component, E_Discriminant) then
17883 Original_Comp := Original_Record_Component (C);
17886 if No (Original_Comp) then
17888 -- Premature usage, or previous error
17893 Original_Type := Scope (Original_Comp);
17894 Type_Scope := Scope (Base_Type (Scope (C)));
17897 -- This test only concerns tagged types
17899 if not Is_Tagged_Type (Original_Type) then
17902 -- If it is _Parent or _Tag, there is no visibility issue
17904 elsif not Comes_From_Source (Original_Comp) then
17907 -- Discriminants are visible unless the (private) type has unknown
17908 -- discriminants. If the discriminant reference is inserted for a
17909 -- discriminant check on a full view it is also visible.
17911 elsif Ekind (Original_Comp) = E_Discriminant
17913 (not Has_Unknown_Discriminants (Original_Type)
17914 or else (Present (N)
17915 and then Nkind (N) = N_Selected_Component
17916 and then Nkind (Prefix (N)) = N_Type_Conversion
17917 and then not Comes_From_Source (Prefix (N))))
17921 -- In the body of an instantiation, no need to check for the visibility
17924 elsif In_Instance_Body then
17927 -- If the component has been declared in an ancestor which is currently
17928 -- a private type, then it is not visible. The same applies if the
17929 -- component's containing type is not in an open scope and the original
17930 -- component's enclosing type is a visible full view of a private type
17931 -- (which can occur in cases where an attempt is being made to reference
17932 -- a component in a sibling package that is inherited from a visible
17933 -- component of a type in an ancestor package; the component in the
17934 -- sibling package should not be visible even though the component it
17935 -- inherited from is visible). This does not apply however in the case
17936 -- where the scope of the type is a private child unit, or when the
17937 -- parent comes from a local package in which the ancestor is currently
17938 -- visible. The latter suppression of visibility is needed for cases
17939 -- that are tested in B730006.
17941 elsif Is_Private_Type (Original_Type)
17943 (not Is_Private_Descendant (Type_Scope)
17944 and then not In_Open_Scopes (Type_Scope)
17945 and then Has_Private_Declaration (Original_Type))
17947 -- If the type derives from an entity in a formal package, there
17948 -- are no additional visible components.
17950 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
17951 N_Formal_Package_Declaration
17955 -- if we are not in the private part of the current package, there
17956 -- are no additional visible components.
17958 elsif Ekind (Scope (Current_Scope)) = E_Package
17959 and then not In_Private_Part (Scope (Current_Scope))
17964 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
17965 and then In_Open_Scopes (Scope (Original_Type))
17966 and then Is_Local_Type (Type_Scope);
17969 -- There is another weird way in which a component may be invisible when
17970 -- the private and the full view are not derived from the same ancestor.
17971 -- Here is an example :
17973 -- type A1 is tagged record F1 : integer; end record;
17974 -- type A2 is new A1 with record F2 : integer; end record;
17975 -- type T is new A1 with private;
17977 -- type T is new A2 with null record;
17979 -- In this case, the full view of T inherits F1 and F2 but the private
17980 -- view inherits only F1
17984 Ancestor : Entity_Id := Scope (C);
17988 if Ancestor = Original_Type then
17991 -- The ancestor may have a partial view of the original type,
17992 -- but if the full view is in scope, as in a child body, the
17993 -- component is visible.
17995 elsif In_Private_Part (Scope (Original_Type))
17996 and then Full_View (Ancestor) = Original_Type
18000 elsif Ancestor = Etype (Ancestor) then
18002 -- No further ancestors to examine
18007 Ancestor := Etype (Ancestor);
18011 end Is_Visible_Component;
18013 --------------------------
18014 -- Make_Class_Wide_Type --
18015 --------------------------
18017 procedure Make_Class_Wide_Type (T : Entity_Id) is
18018 CW_Type : Entity_Id;
18020 Next_E : Entity_Id;
18023 if Present (Class_Wide_Type (T)) then
18025 -- The class-wide type is a partially decorated entity created for a
18026 -- unanalyzed tagged type referenced through a limited with clause.
18027 -- When the tagged type is analyzed, its class-wide type needs to be
18028 -- redecorated. Note that we reuse the entity created by Decorate_
18029 -- Tagged_Type in order to preserve all links.
18031 if Materialize_Entity (Class_Wide_Type (T)) then
18032 CW_Type := Class_Wide_Type (T);
18033 Set_Materialize_Entity (CW_Type, False);
18035 -- The class wide type can have been defined by the partial view, in
18036 -- which case everything is already done.
18042 -- Default case, we need to create a new class-wide type
18046 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
18049 -- Inherit root type characteristics
18051 CW_Name := Chars (CW_Type);
18052 Next_E := Next_Entity (CW_Type);
18053 Copy_Node (T, CW_Type);
18054 Set_Comes_From_Source (CW_Type, False);
18055 Set_Chars (CW_Type, CW_Name);
18056 Set_Parent (CW_Type, Parent (T));
18057 Set_Next_Entity (CW_Type, Next_E);
18059 -- Ensure we have a new freeze node for the class-wide type. The partial
18060 -- view may have freeze action of its own, requiring a proper freeze
18061 -- node, and the same freeze node cannot be shared between the two
18064 Set_Has_Delayed_Freeze (CW_Type);
18065 Set_Freeze_Node (CW_Type, Empty);
18067 -- Customize the class-wide type: It has no prim. op., it cannot be
18068 -- abstract and its Etype points back to the specific root type.
18070 Set_Ekind (CW_Type, E_Class_Wide_Type);
18071 Set_Is_Tagged_Type (CW_Type, True);
18072 Set_Direct_Primitive_Operations (CW_Type, New_Elmt_List);
18073 Set_Is_Abstract_Type (CW_Type, False);
18074 Set_Is_Constrained (CW_Type, False);
18075 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
18076 Set_Default_SSO (CW_Type);
18078 if Ekind (T) = E_Class_Wide_Subtype then
18079 Set_Etype (CW_Type, Etype (Base_Type (T)));
18081 Set_Etype (CW_Type, T);
18084 Set_No_Tagged_Streams_Pragma (CW_Type, No_Tagged_Streams);
18086 -- If this is the class_wide type of a constrained subtype, it does
18087 -- not have discriminants.
18089 Set_Has_Discriminants (CW_Type,
18090 Has_Discriminants (T) and then not Is_Constrained (T));
18092 Set_Has_Unknown_Discriminants (CW_Type, True);
18093 Set_Class_Wide_Type (T, CW_Type);
18094 Set_Equivalent_Type (CW_Type, Empty);
18096 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
18098 Set_Class_Wide_Type (CW_Type, CW_Type);
18100 -- Inherit the "ghostness" from the root tagged type
18102 if Ghost_Mode > None or else Is_Ghost_Entity (T) then
18103 Set_Is_Ghost_Entity (CW_Type);
18105 end Make_Class_Wide_Type;
18111 procedure Make_Index
18113 Related_Nod : Node_Id;
18114 Related_Id : Entity_Id := Empty;
18115 Suffix_Index : Nat := 1;
18116 In_Iter_Schm : Boolean := False)
18120 Def_Id : Entity_Id := Empty;
18121 Found : Boolean := False;
18124 -- For a discrete range used in a constrained array definition and
18125 -- defined by a range, an implicit conversion to the predefined type
18126 -- INTEGER is assumed if each bound is either a numeric literal, a named
18127 -- number, or an attribute, and the type of both bounds (prior to the
18128 -- implicit conversion) is the type universal_integer. Otherwise, both
18129 -- bounds must be of the same discrete type, other than universal
18130 -- integer; this type must be determinable independently of the
18131 -- context, but using the fact that the type must be discrete and that
18132 -- both bounds must have the same type.
18134 -- Character literals also have a universal type in the absence of
18135 -- of additional context, and are resolved to Standard_Character.
18137 if Nkind (N) = N_Range then
18139 -- The index is given by a range constraint. The bounds are known
18140 -- to be of a consistent type.
18142 if not Is_Overloaded (N) then
18145 -- For universal bounds, choose the specific predefined type
18147 if T = Universal_Integer then
18148 T := Standard_Integer;
18150 elsif T = Any_Character then
18151 Ambiguous_Character (Low_Bound (N));
18153 T := Standard_Character;
18156 -- The node may be overloaded because some user-defined operators
18157 -- are available, but if a universal interpretation exists it is
18158 -- also the selected one.
18160 elsif Universal_Interpretation (N) = Universal_Integer then
18161 T := Standard_Integer;
18167 Ind : Interp_Index;
18171 Get_First_Interp (N, Ind, It);
18172 while Present (It.Typ) loop
18173 if Is_Discrete_Type (It.Typ) then
18176 and then not Covers (It.Typ, T)
18177 and then not Covers (T, It.Typ)
18179 Error_Msg_N ("ambiguous bounds in discrete range", N);
18187 Get_Next_Interp (Ind, It);
18190 if T = Any_Type then
18191 Error_Msg_N ("discrete type required for range", N);
18192 Set_Etype (N, Any_Type);
18195 elsif T = Universal_Integer then
18196 T := Standard_Integer;
18201 if not Is_Discrete_Type (T) then
18202 Error_Msg_N ("discrete type required for range", N);
18203 Set_Etype (N, Any_Type);
18207 if Nkind (Low_Bound (N)) = N_Attribute_Reference
18208 and then Attribute_Name (Low_Bound (N)) = Name_First
18209 and then Is_Entity_Name (Prefix (Low_Bound (N)))
18210 and then Is_Type (Entity (Prefix (Low_Bound (N))))
18211 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (N))))
18213 -- The type of the index will be the type of the prefix, as long
18214 -- as the upper bound is 'Last of the same type.
18216 Def_Id := Entity (Prefix (Low_Bound (N)));
18218 if Nkind (High_Bound (N)) /= N_Attribute_Reference
18219 or else Attribute_Name (High_Bound (N)) /= Name_Last
18220 or else not Is_Entity_Name (Prefix (High_Bound (N)))
18221 or else Entity (Prefix (High_Bound (N))) /= Def_Id
18228 Process_Range_Expr_In_Decl (R, T, In_Iter_Schm => In_Iter_Schm);
18230 elsif Nkind (N) = N_Subtype_Indication then
18232 -- The index is given by a subtype with a range constraint
18234 T := Base_Type (Entity (Subtype_Mark (N)));
18236 if not Is_Discrete_Type (T) then
18237 Error_Msg_N ("discrete type required for range", N);
18238 Set_Etype (N, Any_Type);
18242 R := Range_Expression (Constraint (N));
18245 Process_Range_Expr_In_Decl
18246 (R, Entity (Subtype_Mark (N)), In_Iter_Schm => In_Iter_Schm);
18248 elsif Nkind (N) = N_Attribute_Reference then
18250 -- Catch beginner's error (use of attribute other than 'Range)
18252 if Attribute_Name (N) /= Name_Range then
18253 Error_Msg_N ("expect attribute ''Range", N);
18254 Set_Etype (N, Any_Type);
18258 -- If the node denotes the range of a type mark, that is also the
18259 -- resulting type, and we do not need to create an Itype for it.
18261 if Is_Entity_Name (Prefix (N))
18262 and then Comes_From_Source (N)
18263 and then Is_Type (Entity (Prefix (N)))
18264 and then Is_Discrete_Type (Entity (Prefix (N)))
18266 Def_Id := Entity (Prefix (N));
18269 Analyze_And_Resolve (N);
18273 -- If none of the above, must be a subtype. We convert this to a
18274 -- range attribute reference because in the case of declared first
18275 -- named subtypes, the types in the range reference can be different
18276 -- from the type of the entity. A range attribute normalizes the
18277 -- reference and obtains the correct types for the bounds.
18279 -- This transformation is in the nature of an expansion, is only
18280 -- done if expansion is active. In particular, it is not done on
18281 -- formal generic types, because we need to retain the name of the
18282 -- original index for instantiation purposes.
18285 if not Is_Entity_Name (N) or else not Is_Type (Entity (N)) then
18286 Error_Msg_N ("invalid subtype mark in discrete range ", N);
18287 Set_Etype (N, Any_Integer);
18291 -- The type mark may be that of an incomplete type. It is only
18292 -- now that we can get the full view, previous analysis does
18293 -- not look specifically for a type mark.
18295 Set_Entity (N, Get_Full_View (Entity (N)));
18296 Set_Etype (N, Entity (N));
18297 Def_Id := Entity (N);
18299 if not Is_Discrete_Type (Def_Id) then
18300 Error_Msg_N ("discrete type required for index", N);
18301 Set_Etype (N, Any_Type);
18306 if Expander_Active then
18308 Make_Attribute_Reference (Sloc (N),
18309 Attribute_Name => Name_Range,
18310 Prefix => Relocate_Node (N)));
18312 -- The original was a subtype mark that does not freeze. This
18313 -- means that the rewritten version must not freeze either.
18315 Set_Must_Not_Freeze (N);
18316 Set_Must_Not_Freeze (Prefix (N));
18317 Analyze_And_Resolve (N);
18321 -- If expander is inactive, type is legal, nothing else to construct
18328 if not Is_Discrete_Type (T) then
18329 Error_Msg_N ("discrete type required for range", N);
18330 Set_Etype (N, Any_Type);
18333 elsif T = Any_Type then
18334 Set_Etype (N, Any_Type);
18338 -- We will now create the appropriate Itype to describe the range, but
18339 -- first a check. If we originally had a subtype, then we just label
18340 -- the range with this subtype. Not only is there no need to construct
18341 -- a new subtype, but it is wrong to do so for two reasons:
18343 -- 1. A legality concern, if we have a subtype, it must not freeze,
18344 -- and the Itype would cause freezing incorrectly
18346 -- 2. An efficiency concern, if we created an Itype, it would not be
18347 -- recognized as the same type for the purposes of eliminating
18348 -- checks in some circumstances.
18350 -- We signal this case by setting the subtype entity in Def_Id
18352 if No (Def_Id) then
18354 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
18355 Set_Etype (Def_Id, Base_Type (T));
18357 if Is_Signed_Integer_Type (T) then
18358 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
18360 elsif Is_Modular_Integer_Type (T) then
18361 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
18364 Set_Ekind (Def_Id, E_Enumeration_Subtype);
18365 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
18366 Set_First_Literal (Def_Id, First_Literal (T));
18369 Set_Size_Info (Def_Id, (T));
18370 Set_RM_Size (Def_Id, RM_Size (T));
18371 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
18373 Set_Scalar_Range (Def_Id, R);
18374 Conditional_Delay (Def_Id, T);
18376 if Nkind (N) = N_Subtype_Indication then
18377 Inherit_Predicate_Flags (Def_Id, Entity (Subtype_Mark (N)));
18380 -- In the subtype indication case, if the immediate parent of the
18381 -- new subtype is non-static, then the subtype we create is non-
18382 -- static, even if its bounds are static.
18384 if Nkind (N) = N_Subtype_Indication
18385 and then not Is_OK_Static_Subtype (Entity (Subtype_Mark (N)))
18387 Set_Is_Non_Static_Subtype (Def_Id);
18391 -- Final step is to label the index with this constructed type
18393 Set_Etype (N, Def_Id);
18396 ------------------------------
18397 -- Modular_Type_Declaration --
18398 ------------------------------
18400 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
18401 Mod_Expr : constant Node_Id := Expression (Def);
18404 procedure Set_Modular_Size (Bits : Int);
18405 -- Sets RM_Size to Bits, and Esize to normal word size above this
18407 ----------------------
18408 -- Set_Modular_Size --
18409 ----------------------
18411 procedure Set_Modular_Size (Bits : Int) is
18413 Set_RM_Size (T, UI_From_Int (Bits));
18418 elsif Bits <= 16 then
18419 Init_Esize (T, 16);
18421 elsif Bits <= 32 then
18422 Init_Esize (T, 32);
18425 Init_Esize (T, System_Max_Binary_Modulus_Power);
18428 if not Non_Binary_Modulus (T) and then Esize (T) = RM_Size (T) then
18429 Set_Is_Known_Valid (T);
18431 end Set_Modular_Size;
18433 -- Start of processing for Modular_Type_Declaration
18436 -- If the mod expression is (exactly) 2 * literal, where literal is
18437 -- 64 or less,then almost certainly the * was meant to be **. Warn.
18439 if Warn_On_Suspicious_Modulus_Value
18440 and then Nkind (Mod_Expr) = N_Op_Multiply
18441 and then Nkind (Left_Opnd (Mod_Expr)) = N_Integer_Literal
18442 and then Intval (Left_Opnd (Mod_Expr)) = Uint_2
18443 and then Nkind (Right_Opnd (Mod_Expr)) = N_Integer_Literal
18444 and then Intval (Right_Opnd (Mod_Expr)) <= Uint_64
18447 ("suspicious MOD value, was '*'* intended'??M?", Mod_Expr);
18450 -- Proceed with analysis of mod expression
18452 Analyze_And_Resolve (Mod_Expr, Any_Integer);
18454 Set_Ekind (T, E_Modular_Integer_Type);
18455 Init_Alignment (T);
18456 Set_Is_Constrained (T);
18458 if not Is_OK_Static_Expression (Mod_Expr) then
18459 Flag_Non_Static_Expr
18460 ("non-static expression used for modular type bound!", Mod_Expr);
18461 M_Val := 2 ** System_Max_Binary_Modulus_Power;
18463 M_Val := Expr_Value (Mod_Expr);
18467 Error_Msg_N ("modulus value must be positive", Mod_Expr);
18468 M_Val := 2 ** System_Max_Binary_Modulus_Power;
18471 if M_Val > 2 ** Standard_Long_Integer_Size then
18472 Check_Restriction (No_Long_Long_Integers, Mod_Expr);
18475 Set_Modulus (T, M_Val);
18477 -- Create bounds for the modular type based on the modulus given in
18478 -- the type declaration and then analyze and resolve those bounds.
18480 Set_Scalar_Range (T,
18481 Make_Range (Sloc (Mod_Expr),
18482 Low_Bound => Make_Integer_Literal (Sloc (Mod_Expr), 0),
18483 High_Bound => Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
18485 -- Properly analyze the literals for the range. We do this manually
18486 -- because we can't go calling Resolve, since we are resolving these
18487 -- bounds with the type, and this type is certainly not complete yet.
18489 Set_Etype (Low_Bound (Scalar_Range (T)), T);
18490 Set_Etype (High_Bound (Scalar_Range (T)), T);
18491 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
18492 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
18494 -- Loop through powers of two to find number of bits required
18496 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
18500 if M_Val = 2 ** Bits then
18501 Set_Modular_Size (Bits);
18506 elsif M_Val < 2 ** Bits then
18507 Check_SPARK_05_Restriction ("modulus should be a power of 2", T);
18508 Set_Non_Binary_Modulus (T);
18510 if Bits > System_Max_Nonbinary_Modulus_Power then
18511 Error_Msg_Uint_1 :=
18512 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
18514 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
18515 Set_Modular_Size (System_Max_Binary_Modulus_Power);
18519 -- In the nonbinary case, set size as per RM 13.3(55)
18521 Set_Modular_Size (Bits);
18528 -- If we fall through, then the size exceed System.Max_Binary_Modulus
18529 -- so we just signal an error and set the maximum size.
18531 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
18532 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
18534 Set_Modular_Size (System_Max_Binary_Modulus_Power);
18535 Init_Alignment (T);
18537 end Modular_Type_Declaration;
18539 --------------------------
18540 -- New_Concatenation_Op --
18541 --------------------------
18543 procedure New_Concatenation_Op (Typ : Entity_Id) is
18544 Loc : constant Source_Ptr := Sloc (Typ);
18547 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
18548 -- Create abbreviated declaration for the formal of a predefined
18549 -- Operator 'Op' of type 'Typ'
18551 --------------------
18552 -- Make_Op_Formal --
18553 --------------------
18555 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
18556 Formal : Entity_Id;
18558 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
18559 Set_Etype (Formal, Typ);
18560 Set_Mechanism (Formal, Default_Mechanism);
18562 end Make_Op_Formal;
18564 -- Start of processing for New_Concatenation_Op
18567 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
18569 Set_Ekind (Op, E_Operator);
18570 Set_Scope (Op, Current_Scope);
18571 Set_Etype (Op, Typ);
18572 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
18573 Set_Is_Immediately_Visible (Op);
18574 Set_Is_Intrinsic_Subprogram (Op);
18575 Set_Has_Completion (Op);
18576 Append_Entity (Op, Current_Scope);
18578 Set_Name_Entity_Id (Name_Op_Concat, Op);
18580 Append_Entity (Make_Op_Formal (Typ, Op), Op);
18581 Append_Entity (Make_Op_Formal (Typ, Op), Op);
18582 end New_Concatenation_Op;
18584 -------------------------
18585 -- OK_For_Limited_Init --
18586 -------------------------
18588 -- ???Check all calls of this, and compare the conditions under which it's
18591 function OK_For_Limited_Init
18593 Exp : Node_Id) return Boolean
18596 return Is_CPP_Constructor_Call (Exp)
18597 or else (Ada_Version >= Ada_2005
18598 and then not Debug_Flag_Dot_L
18599 and then OK_For_Limited_Init_In_05 (Typ, Exp));
18600 end OK_For_Limited_Init;
18602 -------------------------------
18603 -- OK_For_Limited_Init_In_05 --
18604 -------------------------------
18606 function OK_For_Limited_Init_In_05
18608 Exp : Node_Id) return Boolean
18611 -- An object of a limited interface type can be initialized with any
18612 -- expression of a nonlimited descendant type.
18614 if Is_Class_Wide_Type (Typ)
18615 and then Is_Limited_Interface (Typ)
18616 and then not Is_Limited_Type (Etype (Exp))
18621 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
18622 -- case of limited aggregates (including extension aggregates), and
18623 -- function calls. The function call may have been given in prefixed
18624 -- notation, in which case the original node is an indexed component.
18625 -- If the function is parameterless, the original node was an explicit
18626 -- dereference. The function may also be parameterless, in which case
18627 -- the source node is just an identifier.
18629 -- A branch of a conditional expression may have been removed if the
18630 -- condition is statically known. This happens during expansion, and
18631 -- thus will not happen if previous errors were encountered. The check
18632 -- will have been performed on the chosen branch, which replaces the
18633 -- original conditional expression.
18639 case Nkind (Original_Node (Exp)) is
18640 when N_Aggregate | N_Extension_Aggregate | N_Function_Call | N_Op =>
18643 when N_Identifier =>
18644 return Present (Entity (Original_Node (Exp)))
18645 and then Ekind (Entity (Original_Node (Exp))) = E_Function;
18647 when N_Qualified_Expression =>
18649 OK_For_Limited_Init_In_05
18650 (Typ, Expression (Original_Node (Exp)));
18652 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
18653 -- with a function call, the expander has rewritten the call into an
18654 -- N_Type_Conversion node to force displacement of the pointer to
18655 -- reference the component containing the secondary dispatch table.
18656 -- Otherwise a type conversion is not a legal context.
18657 -- A return statement for a build-in-place function returning a
18658 -- synchronized type also introduces an unchecked conversion.
18660 when N_Type_Conversion |
18661 N_Unchecked_Type_Conversion =>
18662 return not Comes_From_Source (Exp)
18664 OK_For_Limited_Init_In_05
18665 (Typ, Expression (Original_Node (Exp)));
18667 when N_Indexed_Component |
18668 N_Selected_Component |
18669 N_Explicit_Dereference =>
18670 return Nkind (Exp) = N_Function_Call;
18672 -- A use of 'Input is a function call, hence allowed. Normally the
18673 -- attribute will be changed to a call, but the attribute by itself
18674 -- can occur with -gnatc.
18676 when N_Attribute_Reference =>
18677 return Attribute_Name (Original_Node (Exp)) = Name_Input;
18679 -- For a case expression, all dependent expressions must be legal
18681 when N_Case_Expression =>
18686 Alt := First (Alternatives (Original_Node (Exp)));
18687 while Present (Alt) loop
18688 if not OK_For_Limited_Init_In_05 (Typ, Expression (Alt)) then
18698 -- For an if expression, all dependent expressions must be legal
18700 when N_If_Expression =>
18702 Then_Expr : constant Node_Id :=
18703 Next (First (Expressions (Original_Node (Exp))));
18704 Else_Expr : constant Node_Id := Next (Then_Expr);
18706 return OK_For_Limited_Init_In_05 (Typ, Then_Expr)
18708 OK_For_Limited_Init_In_05 (Typ, Else_Expr);
18714 end OK_For_Limited_Init_In_05;
18716 -------------------------------------------
18717 -- Ordinary_Fixed_Point_Type_Declaration --
18718 -------------------------------------------
18720 procedure Ordinary_Fixed_Point_Type_Declaration
18724 Loc : constant Source_Ptr := Sloc (Def);
18725 Delta_Expr : constant Node_Id := Delta_Expression (Def);
18726 RRS : constant Node_Id := Real_Range_Specification (Def);
18727 Implicit_Base : Entity_Id;
18734 Check_Restriction (No_Fixed_Point, Def);
18736 -- Create implicit base type
18739 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
18740 Set_Etype (Implicit_Base, Implicit_Base);
18742 -- Analyze and process delta expression
18744 Analyze_And_Resolve (Delta_Expr, Any_Real);
18746 Check_Delta_Expression (Delta_Expr);
18747 Delta_Val := Expr_Value_R (Delta_Expr);
18749 Set_Delta_Value (Implicit_Base, Delta_Val);
18751 -- Compute default small from given delta, which is the largest power
18752 -- of two that does not exceed the given delta value.
18762 if Delta_Val < Ureal_1 then
18763 while Delta_Val < Tmp loop
18764 Tmp := Tmp / Ureal_2;
18765 Scale := Scale + 1;
18770 Tmp := Tmp * Ureal_2;
18771 exit when Tmp > Delta_Val;
18772 Scale := Scale - 1;
18776 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
18779 Set_Small_Value (Implicit_Base, Small_Val);
18781 -- If no range was given, set a dummy range
18783 if RRS <= Empty_Or_Error then
18784 Low_Val := -Small_Val;
18785 High_Val := Small_Val;
18787 -- Otherwise analyze and process given range
18791 Low : constant Node_Id := Low_Bound (RRS);
18792 High : constant Node_Id := High_Bound (RRS);
18795 Analyze_And_Resolve (Low, Any_Real);
18796 Analyze_And_Resolve (High, Any_Real);
18797 Check_Real_Bound (Low);
18798 Check_Real_Bound (High);
18800 -- Obtain and set the range
18802 Low_Val := Expr_Value_R (Low);
18803 High_Val := Expr_Value_R (High);
18805 if Low_Val > High_Val then
18806 Error_Msg_NE ("??fixed point type& has null range", Def, T);
18811 -- The range for both the implicit base and the declared first subtype
18812 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
18813 -- set a temporary range in place. Note that the bounds of the base
18814 -- type will be widened to be symmetrical and to fill the available
18815 -- bits when the type is frozen.
18817 -- We could do this with all discrete types, and probably should, but
18818 -- we absolutely have to do it for fixed-point, since the end-points
18819 -- of the range and the size are determined by the small value, which
18820 -- could be reset before the freeze point.
18822 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
18823 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
18825 -- Complete definition of first subtype. The inheritance of the rep item
18826 -- chain ensures that SPARK-related pragmas are not clobbered when the
18827 -- ordinary fixed point type acts as a full view of a private type.
18829 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
18830 Set_Etype (T, Implicit_Base);
18831 Init_Size_Align (T);
18832 Inherit_Rep_Item_Chain (T, Implicit_Base);
18833 Set_Small_Value (T, Small_Val);
18834 Set_Delta_Value (T, Delta_Val);
18835 Set_Is_Constrained (T);
18836 end Ordinary_Fixed_Point_Type_Declaration;
18838 ----------------------------------
18839 -- Preanalyze_Assert_Expression --
18840 ----------------------------------
18842 procedure Preanalyze_Assert_Expression (N : Node_Id; T : Entity_Id) is
18844 In_Assertion_Expr := In_Assertion_Expr + 1;
18845 Preanalyze_Spec_Expression (N, T);
18846 In_Assertion_Expr := In_Assertion_Expr - 1;
18847 end Preanalyze_Assert_Expression;
18849 -----------------------------------
18850 -- Preanalyze_Default_Expression --
18851 -----------------------------------
18853 procedure Preanalyze_Default_Expression (N : Node_Id; T : Entity_Id) is
18854 Save_In_Default_Expr : constant Boolean := In_Default_Expr;
18856 In_Default_Expr := True;
18857 Preanalyze_Spec_Expression (N, T);
18858 In_Default_Expr := Save_In_Default_Expr;
18859 end Preanalyze_Default_Expression;
18861 --------------------------------
18862 -- Preanalyze_Spec_Expression --
18863 --------------------------------
18865 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
18866 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
18868 In_Spec_Expression := True;
18869 Preanalyze_And_Resolve (N, T);
18870 In_Spec_Expression := Save_In_Spec_Expression;
18871 end Preanalyze_Spec_Expression;
18873 ----------------------------------------
18874 -- Prepare_Private_Subtype_Completion --
18875 ----------------------------------------
18877 procedure Prepare_Private_Subtype_Completion
18879 Related_Nod : Node_Id)
18881 Id_B : constant Entity_Id := Base_Type (Id);
18882 Full_B : Entity_Id := Full_View (Id_B);
18886 if Present (Full_B) then
18888 -- Get to the underlying full view if necessary
18890 if Is_Private_Type (Full_B)
18891 and then Present (Underlying_Full_View (Full_B))
18893 Full_B := Underlying_Full_View (Full_B);
18896 -- The Base_Type is already completed, we can complete the subtype
18897 -- now. We have to create a new entity with the same name, Thus we
18898 -- can't use Create_Itype.
18900 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
18901 Set_Is_Itype (Full);
18902 Set_Associated_Node_For_Itype (Full, Related_Nod);
18903 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
18906 -- The parent subtype may be private, but the base might not, in some
18907 -- nested instances. In that case, the subtype does not need to be
18908 -- exchanged. It would still be nice to make private subtypes and their
18909 -- bases consistent at all times ???
18911 if Is_Private_Type (Id_B) then
18912 Append_Elmt (Id, Private_Dependents (Id_B));
18914 end Prepare_Private_Subtype_Completion;
18916 ---------------------------
18917 -- Process_Discriminants --
18918 ---------------------------
18920 procedure Process_Discriminants
18922 Prev : Entity_Id := Empty)
18924 Elist : constant Elist_Id := New_Elmt_List;
18927 Discr_Number : Uint;
18928 Discr_Type : Entity_Id;
18929 Default_Present : Boolean := False;
18930 Default_Not_Present : Boolean := False;
18933 -- A composite type other than an array type can have discriminants.
18934 -- On entry, the current scope is the composite type.
18936 -- The discriminants are initially entered into the scope of the type
18937 -- via Enter_Name with the default Ekind of E_Void to prevent premature
18938 -- use, as explained at the end of this procedure.
18940 Discr := First (Discriminant_Specifications (N));
18941 while Present (Discr) loop
18942 Enter_Name (Defining_Identifier (Discr));
18944 -- For navigation purposes we add a reference to the discriminant
18945 -- in the entity for the type. If the current declaration is a
18946 -- completion, place references on the partial view. Otherwise the
18947 -- type is the current scope.
18949 if Present (Prev) then
18951 -- The references go on the partial view, if present. If the
18952 -- partial view has discriminants, the references have been
18953 -- generated already.
18955 if not Has_Discriminants (Prev) then
18956 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
18960 (Current_Scope, Defining_Identifier (Discr), 'd');
18963 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
18964 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
18966 -- Ada 2005 (AI-254)
18968 if Present (Access_To_Subprogram_Definition
18969 (Discriminant_Type (Discr)))
18970 and then Protected_Present (Access_To_Subprogram_Definition
18971 (Discriminant_Type (Discr)))
18974 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
18978 Find_Type (Discriminant_Type (Discr));
18979 Discr_Type := Etype (Discriminant_Type (Discr));
18981 if Error_Posted (Discriminant_Type (Discr)) then
18982 Discr_Type := Any_Type;
18986 -- Handling of discriminants that are access types
18988 if Is_Access_Type (Discr_Type) then
18990 -- Ada 2005 (AI-230): Access discriminant allowed in non-
18991 -- limited record types
18993 if Ada_Version < Ada_2005 then
18994 Check_Access_Discriminant_Requires_Limited
18995 (Discr, Discriminant_Type (Discr));
18998 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
19000 ("(Ada 83) access discriminant not allowed", Discr);
19003 -- If not access type, must be a discrete type
19005 elsif not Is_Discrete_Type (Discr_Type) then
19007 ("discriminants must have a discrete or access type",
19008 Discriminant_Type (Discr));
19011 Set_Etype (Defining_Identifier (Discr), Discr_Type);
19013 -- If a discriminant specification includes the assignment compound
19014 -- delimiter followed by an expression, the expression is the default
19015 -- expression of the discriminant; the default expression must be of
19016 -- the type of the discriminant. (RM 3.7.1) Since this expression is
19017 -- a default expression, we do the special preanalysis, since this
19018 -- expression does not freeze (see section "Handling of Default and
19019 -- Per-Object Expressions" in spec of package Sem).
19021 if Present (Expression (Discr)) then
19022 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
19026 if Nkind (N) = N_Formal_Type_Declaration then
19028 ("discriminant defaults not allowed for formal type",
19029 Expression (Discr));
19031 -- Flag an error for a tagged type with defaulted discriminants,
19032 -- excluding limited tagged types when compiling for Ada 2012
19033 -- (see AI05-0214).
19035 elsif Is_Tagged_Type (Current_Scope)
19036 and then (not Is_Limited_Type (Current_Scope)
19037 or else Ada_Version < Ada_2012)
19038 and then Comes_From_Source (N)
19040 -- Note: see similar test in Check_Or_Process_Discriminants, to
19041 -- handle the (illegal) case of the completion of an untagged
19042 -- view with discriminants with defaults by a tagged full view.
19043 -- We skip the check if Discr does not come from source, to
19044 -- account for the case of an untagged derived type providing
19045 -- defaults for a renamed discriminant from a private untagged
19046 -- ancestor with a tagged full view (ACATS B460006).
19048 if Ada_Version >= Ada_2012 then
19050 ("discriminants of nonlimited tagged type cannot have"
19052 Expression (Discr));
19055 ("discriminants of tagged type cannot have defaults",
19056 Expression (Discr));
19060 Default_Present := True;
19061 Append_Elmt (Expression (Discr), Elist);
19063 -- Tag the defining identifiers for the discriminants with
19064 -- their corresponding default expressions from the tree.
19066 Set_Discriminant_Default_Value
19067 (Defining_Identifier (Discr), Expression (Discr));
19070 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag
19071 -- gets set unless we can be sure that no range check is required.
19073 if (GNATprove_Mode or not Expander_Active)
19076 (Expression (Discr), Discr_Type, Assume_Valid => True)
19078 Set_Do_Range_Check (Expression (Discr));
19081 -- No default discriminant value given
19084 Default_Not_Present := True;
19087 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
19088 -- Discr_Type but with the null-exclusion attribute
19090 if Ada_Version >= Ada_2005 then
19092 -- Ada 2005 (AI-231): Static checks
19094 if Can_Never_Be_Null (Discr_Type) then
19095 Null_Exclusion_Static_Checks (Discr);
19097 elsif Is_Access_Type (Discr_Type)
19098 and then Null_Exclusion_Present (Discr)
19100 -- No need to check itypes because in their case this check
19101 -- was done at their point of creation
19103 and then not Is_Itype (Discr_Type)
19105 if Can_Never_Be_Null (Discr_Type) then
19107 ("`NOT NULL` not allowed (& already excludes null)",
19112 Set_Etype (Defining_Identifier (Discr),
19113 Create_Null_Excluding_Itype
19115 Related_Nod => Discr));
19117 -- Check for improper null exclusion if the type is otherwise
19118 -- legal for a discriminant.
19120 elsif Null_Exclusion_Present (Discr)
19121 and then Is_Discrete_Type (Discr_Type)
19124 ("null exclusion can only apply to an access type", Discr);
19127 -- Ada 2005 (AI-402): access discriminants of nonlimited types
19128 -- can't have defaults. Synchronized types, or types that are
19129 -- explicitly limited are fine, but special tests apply to derived
19130 -- types in generics: in a generic body we have to assume the
19131 -- worst, and therefore defaults are not allowed if the parent is
19132 -- a generic formal private type (see ACATS B370001).
19134 if Is_Access_Type (Discr_Type) and then Default_Present then
19135 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
19136 or else Is_Limited_Record (Current_Scope)
19137 or else Is_Concurrent_Type (Current_Scope)
19138 or else Is_Concurrent_Record_Type (Current_Scope)
19139 or else Ekind (Current_Scope) = E_Limited_Private_Type
19141 if not Is_Derived_Type (Current_Scope)
19142 or else not Is_Generic_Type (Etype (Current_Scope))
19143 or else not In_Package_Body (Scope (Etype (Current_Scope)))
19144 or else Limited_Present
19145 (Type_Definition (Parent (Current_Scope)))
19151 ("access discriminants of nonlimited types cannot "
19152 & "have defaults", Expression (Discr));
19155 elsif Present (Expression (Discr)) then
19157 ("(Ada 2005) access discriminants of nonlimited types "
19158 & "cannot have defaults", Expression (Discr));
19163 -- A discriminant cannot be effectively volatile (SPARK RM 7.1.3(6)).
19164 -- This check is relevant only when SPARK_Mode is on as it is not a
19165 -- standard Ada legality rule.
19168 and then Is_Effectively_Volatile (Defining_Identifier (Discr))
19170 Error_Msg_N ("discriminant cannot be volatile", Discr);
19176 -- An element list consisting of the default expressions of the
19177 -- discriminants is constructed in the above loop and used to set
19178 -- the Discriminant_Constraint attribute for the type. If an object
19179 -- is declared of this (record or task) type without any explicit
19180 -- discriminant constraint given, this element list will form the
19181 -- actual parameters for the corresponding initialization procedure
19184 Set_Discriminant_Constraint (Current_Scope, Elist);
19185 Set_Stored_Constraint (Current_Scope, No_Elist);
19187 -- Default expressions must be provided either for all or for none
19188 -- of the discriminants of a discriminant part. (RM 3.7.1)
19190 if Default_Present and then Default_Not_Present then
19192 ("incomplete specification of defaults for discriminants", N);
19195 -- The use of the name of a discriminant is not allowed in default
19196 -- expressions of a discriminant part if the specification of the
19197 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
19199 -- To detect this, the discriminant names are entered initially with an
19200 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
19201 -- attempt to use a void entity (for example in an expression that is
19202 -- type-checked) produces the error message: premature usage. Now after
19203 -- completing the semantic analysis of the discriminant part, we can set
19204 -- the Ekind of all the discriminants appropriately.
19206 Discr := First (Discriminant_Specifications (N));
19207 Discr_Number := Uint_1;
19208 while Present (Discr) loop
19209 Id := Defining_Identifier (Discr);
19210 Set_Ekind (Id, E_Discriminant);
19211 Init_Component_Location (Id);
19213 Set_Discriminant_Number (Id, Discr_Number);
19215 -- Make sure this is always set, even in illegal programs
19217 Set_Corresponding_Discriminant (Id, Empty);
19219 -- Initialize the Original_Record_Component to the entity itself.
19220 -- Inherit_Components will propagate the right value to
19221 -- discriminants in derived record types.
19223 Set_Original_Record_Component (Id, Id);
19225 -- Create the discriminal for the discriminant
19227 Build_Discriminal (Id);
19230 Discr_Number := Discr_Number + 1;
19233 Set_Has_Discriminants (Current_Scope);
19234 end Process_Discriminants;
19236 -----------------------
19237 -- Process_Full_View --
19238 -----------------------
19240 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
19241 procedure Collect_Implemented_Interfaces
19243 Ifaces : Elist_Id);
19244 -- Ada 2005: Gather all the interfaces that Typ directly or
19245 -- inherently implements. Duplicate entries are not added to
19246 -- the list Ifaces.
19248 ------------------------------------
19249 -- Collect_Implemented_Interfaces --
19250 ------------------------------------
19252 procedure Collect_Implemented_Interfaces
19257 Iface_Elmt : Elmt_Id;
19260 -- Abstract interfaces are only associated with tagged record types
19262 if not Is_Tagged_Type (Typ) or else not Is_Record_Type (Typ) then
19266 -- Recursively climb to the ancestors
19268 if Etype (Typ) /= Typ
19270 -- Protect the frontend against wrong cyclic declarations like:
19272 -- type B is new A with private;
19273 -- type C is new A with private;
19275 -- type B is new C with null record;
19276 -- type C is new B with null record;
19278 and then Etype (Typ) /= Priv_T
19279 and then Etype (Typ) /= Full_T
19281 -- Keep separate the management of private type declarations
19283 if Ekind (Typ) = E_Record_Type_With_Private then
19285 -- Handle the following illegal usage:
19286 -- type Private_Type is tagged private;
19288 -- type Private_Type is new Type_Implementing_Iface;
19290 if Present (Full_View (Typ))
19291 and then Etype (Typ) /= Full_View (Typ)
19293 if Is_Interface (Etype (Typ)) then
19294 Append_Unique_Elmt (Etype (Typ), Ifaces);
19297 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
19300 -- Non-private types
19303 if Is_Interface (Etype (Typ)) then
19304 Append_Unique_Elmt (Etype (Typ), Ifaces);
19307 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
19311 -- Handle entities in the list of abstract interfaces
19313 if Present (Interfaces (Typ)) then
19314 Iface_Elmt := First_Elmt (Interfaces (Typ));
19315 while Present (Iface_Elmt) loop
19316 Iface := Node (Iface_Elmt);
19318 pragma Assert (Is_Interface (Iface));
19320 if not Contain_Interface (Iface, Ifaces) then
19321 Append_Elmt (Iface, Ifaces);
19322 Collect_Implemented_Interfaces (Iface, Ifaces);
19325 Next_Elmt (Iface_Elmt);
19328 end Collect_Implemented_Interfaces;
19332 Full_Indic : Node_Id;
19333 Full_Parent : Entity_Id;
19334 Priv_Parent : Entity_Id;
19336 -- Start of processing for Process_Full_View
19339 -- First some sanity checks that must be done after semantic
19340 -- decoration of the full view and thus cannot be placed with other
19341 -- similar checks in Find_Type_Name
19343 if not Is_Limited_Type (Priv_T)
19344 and then (Is_Limited_Type (Full_T)
19345 or else Is_Limited_Composite (Full_T))
19347 if In_Instance then
19351 ("completion of nonlimited type cannot be limited", Full_T);
19352 Explain_Limited_Type (Full_T, Full_T);
19355 elsif Is_Abstract_Type (Full_T)
19356 and then not Is_Abstract_Type (Priv_T)
19359 ("completion of nonabstract type cannot be abstract", Full_T);
19361 elsif Is_Tagged_Type (Priv_T)
19362 and then Is_Limited_Type (Priv_T)
19363 and then not Is_Limited_Type (Full_T)
19365 -- If pragma CPP_Class was applied to the private declaration
19366 -- propagate the limitedness to the full-view
19368 if Is_CPP_Class (Priv_T) then
19369 Set_Is_Limited_Record (Full_T);
19371 -- GNAT allow its own definition of Limited_Controlled to disobey
19372 -- this rule in order in ease the implementation. This test is safe
19373 -- because Root_Controlled is defined in a child of System that
19374 -- normal programs are not supposed to use.
19376 elsif Is_RTE (Etype (Full_T), RE_Root_Controlled) then
19377 Set_Is_Limited_Composite (Full_T);
19380 ("completion of limited tagged type must be limited", Full_T);
19383 elsif Is_Generic_Type (Priv_T) then
19384 Error_Msg_N ("generic type cannot have a completion", Full_T);
19387 -- Check that ancestor interfaces of private and full views are
19388 -- consistent. We omit this check for synchronized types because
19389 -- they are performed on the corresponding record type when frozen.
19391 if Ada_Version >= Ada_2005
19392 and then Is_Tagged_Type (Priv_T)
19393 and then Is_Tagged_Type (Full_T)
19394 and then not Is_Concurrent_Type (Full_T)
19398 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
19399 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
19402 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
19403 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
19405 -- Ada 2005 (AI-251): The partial view shall be a descendant of
19406 -- an interface type if and only if the full type is descendant
19407 -- of the interface type (AARM 7.3 (7.3/2)).
19409 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
19411 if Present (Iface) then
19413 ("interface in partial view& not implemented by full type "
19414 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
19417 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
19419 if Present (Iface) then
19421 ("interface & not implemented by partial view "
19422 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
19427 if Is_Tagged_Type (Priv_T)
19428 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19429 and then Is_Derived_Type (Full_T)
19431 Priv_Parent := Etype (Priv_T);
19433 -- The full view of a private extension may have been transformed
19434 -- into an unconstrained derived type declaration and a subtype
19435 -- declaration (see build_derived_record_type for details).
19437 if Nkind (N) = N_Subtype_Declaration then
19438 Full_Indic := Subtype_Indication (N);
19439 Full_Parent := Etype (Base_Type (Full_T));
19441 Full_Indic := Subtype_Indication (Type_Definition (N));
19442 Full_Parent := Etype (Full_T);
19445 -- Check that the parent type of the full type is a descendant of
19446 -- the ancestor subtype given in the private extension. If either
19447 -- entity has an Etype equal to Any_Type then we had some previous
19448 -- error situation [7.3(8)].
19450 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
19453 -- Ada 2005 (AI-251): Interfaces in the full type can be given in
19454 -- any order. Therefore we don't have to check that its parent must
19455 -- be a descendant of the parent of the private type declaration.
19457 elsif Is_Interface (Priv_Parent)
19458 and then Is_Interface (Full_Parent)
19462 -- Ada 2005 (AI-251): If the parent of the private type declaration
19463 -- is an interface there is no need to check that it is an ancestor
19464 -- of the associated full type declaration. The required tests for
19465 -- this case are performed by Build_Derived_Record_Type.
19467 elsif not Is_Interface (Base_Type (Priv_Parent))
19468 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
19471 ("parent of full type must descend from parent"
19472 & " of private extension", Full_Indic);
19474 -- First check a formal restriction, and then proceed with checking
19475 -- Ada rules. Since the formal restriction is not a serious error, we
19476 -- don't prevent further error detection for this check, hence the
19480 -- In formal mode, when completing a private extension the type
19481 -- named in the private part must be exactly the same as that
19482 -- named in the visible part.
19484 if Priv_Parent /= Full_Parent then
19485 Error_Msg_Name_1 := Chars (Priv_Parent);
19486 Check_SPARK_05_Restriction ("% expected", Full_Indic);
19489 -- Check the rules of 7.3(10): if the private extension inherits
19490 -- known discriminants, then the full type must also inherit those
19491 -- discriminants from the same (ancestor) type, and the parent
19492 -- subtype of the full type must be constrained if and only if
19493 -- the ancestor subtype of the private extension is constrained.
19495 if No (Discriminant_Specifications (Parent (Priv_T)))
19496 and then not Has_Unknown_Discriminants (Priv_T)
19497 and then Has_Discriminants (Base_Type (Priv_Parent))
19500 Priv_Indic : constant Node_Id :=
19501 Subtype_Indication (Parent (Priv_T));
19503 Priv_Constr : constant Boolean :=
19504 Is_Constrained (Priv_Parent)
19506 Nkind (Priv_Indic) = N_Subtype_Indication
19508 Is_Constrained (Entity (Priv_Indic));
19510 Full_Constr : constant Boolean :=
19511 Is_Constrained (Full_Parent)
19513 Nkind (Full_Indic) = N_Subtype_Indication
19515 Is_Constrained (Entity (Full_Indic));
19517 Priv_Discr : Entity_Id;
19518 Full_Discr : Entity_Id;
19521 Priv_Discr := First_Discriminant (Priv_Parent);
19522 Full_Discr := First_Discriminant (Full_Parent);
19523 while Present (Priv_Discr) and then Present (Full_Discr) loop
19524 if Original_Record_Component (Priv_Discr) =
19525 Original_Record_Component (Full_Discr)
19527 Corresponding_Discriminant (Priv_Discr) =
19528 Corresponding_Discriminant (Full_Discr)
19535 Next_Discriminant (Priv_Discr);
19536 Next_Discriminant (Full_Discr);
19539 if Present (Priv_Discr) or else Present (Full_Discr) then
19541 ("full view must inherit discriminants of the parent"
19542 & " type used in the private extension", Full_Indic);
19544 elsif Priv_Constr and then not Full_Constr then
19546 ("parent subtype of full type must be constrained",
19549 elsif Full_Constr and then not Priv_Constr then
19551 ("parent subtype of full type must be unconstrained",
19556 -- Check the rules of 7.3(12): if a partial view has neither
19557 -- known or unknown discriminants, then the full type
19558 -- declaration shall define a definite subtype.
19560 elsif not Has_Unknown_Discriminants (Priv_T)
19561 and then not Has_Discriminants (Priv_T)
19562 and then not Is_Constrained (Full_T)
19565 ("full view must define a constrained type if partial view"
19566 & " has no discriminants", Full_T);
19569 -- ??????? Do we implement the following properly ?????
19570 -- If the ancestor subtype of a private extension has constrained
19571 -- discriminants, then the parent subtype of the full view shall
19572 -- impose a statically matching constraint on those discriminants
19577 -- For untagged types, verify that a type without discriminants is
19578 -- not completed with an unconstrained type. A separate error message
19579 -- is produced if the full type has defaulted discriminants.
19581 if Is_Definite_Subtype (Priv_T)
19582 and then not Is_Definite_Subtype (Full_T)
19584 Error_Msg_Sloc := Sloc (Parent (Priv_T));
19586 ("full view of& not compatible with declaration#",
19589 if not Is_Tagged_Type (Full_T) then
19591 ("\one is constrained, the other unconstrained", Full_T);
19596 -- AI-419: verify that the use of "limited" is consistent
19599 Orig_Decl : constant Node_Id := Original_Node (N);
19602 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19603 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
19605 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
19607 if not Limited_Present (Parent (Priv_T))
19608 and then not Synchronized_Present (Parent (Priv_T))
19609 and then Limited_Present (Type_Definition (Orig_Decl))
19612 ("full view of non-limited extension cannot be limited", N);
19614 -- Conversely, if the partial view carries the limited keyword,
19615 -- the full view must as well, even if it may be redundant.
19617 elsif Limited_Present (Parent (Priv_T))
19618 and then not Limited_Present (Type_Definition (Orig_Decl))
19621 ("full view of limited extension must be explicitly limited",
19627 -- Ada 2005 (AI-443): A synchronized private extension must be
19628 -- completed by a task or protected type.
19630 if Ada_Version >= Ada_2005
19631 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19632 and then Synchronized_Present (Parent (Priv_T))
19633 and then not Is_Concurrent_Type (Full_T)
19635 Error_Msg_N ("full view of synchronized extension must " &
19636 "be synchronized type", N);
19639 -- Ada 2005 AI-363: if the full view has discriminants with
19640 -- defaults, it is illegal to declare constrained access subtypes
19641 -- whose designated type is the current type. This allows objects
19642 -- of the type that are declared in the heap to be unconstrained.
19644 if not Has_Unknown_Discriminants (Priv_T)
19645 and then not Has_Discriminants (Priv_T)
19646 and then Has_Discriminants (Full_T)
19648 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
19650 Set_Has_Constrained_Partial_View (Full_T);
19651 Set_Has_Constrained_Partial_View (Priv_T);
19654 -- Create a full declaration for all its subtypes recorded in
19655 -- Private_Dependents and swap them similarly to the base type. These
19656 -- are subtypes that have been define before the full declaration of
19657 -- the private type. We also swap the entry in Private_Dependents list
19658 -- so we can properly restore the private view on exit from the scope.
19661 Priv_Elmt : Elmt_Id;
19662 Priv_Scop : Entity_Id;
19667 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
19668 while Present (Priv_Elmt) loop
19669 Priv := Node (Priv_Elmt);
19670 Priv_Scop := Scope (Priv);
19672 if Ekind_In (Priv, E_Private_Subtype,
19673 E_Limited_Private_Subtype,
19674 E_Record_Subtype_With_Private)
19676 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
19677 Set_Is_Itype (Full);
19678 Set_Parent (Full, Parent (Priv));
19679 Set_Associated_Node_For_Itype (Full, N);
19681 -- Now we need to complete the private subtype, but since the
19682 -- base type has already been swapped, we must also swap the
19683 -- subtypes (and thus, reverse the arguments in the call to
19684 -- Complete_Private_Subtype). Also note that we may need to
19685 -- re-establish the scope of the private subtype.
19687 Copy_And_Swap (Priv, Full);
19689 if not In_Open_Scopes (Priv_Scop) then
19690 Push_Scope (Priv_Scop);
19693 -- Reset Priv_Scop to Empty to indicate no scope was pushed
19695 Priv_Scop := Empty;
19698 Complete_Private_Subtype (Full, Priv, Full_T, N);
19700 if Present (Priv_Scop) then
19704 Replace_Elmt (Priv_Elmt, Full);
19707 Next_Elmt (Priv_Elmt);
19711 -- If the private view was tagged, copy the new primitive operations
19712 -- from the private view to the full view.
19714 if Is_Tagged_Type (Full_T) then
19716 Disp_Typ : Entity_Id;
19717 Full_List : Elist_Id;
19719 Prim_Elmt : Elmt_Id;
19720 Priv_List : Elist_Id;
19724 L : Elist_Id) return Boolean;
19725 -- Determine whether list L contains element E
19733 L : Elist_Id) return Boolean
19735 List_Elmt : Elmt_Id;
19738 List_Elmt := First_Elmt (L);
19739 while Present (List_Elmt) loop
19740 if Node (List_Elmt) = E then
19744 Next_Elmt (List_Elmt);
19750 -- Start of processing
19753 if Is_Tagged_Type (Priv_T) then
19754 Priv_List := Primitive_Operations (Priv_T);
19755 Prim_Elmt := First_Elmt (Priv_List);
19757 -- In the case of a concurrent type completing a private tagged
19758 -- type, primitives may have been declared in between the two
19759 -- views. These subprograms need to be wrapped the same way
19760 -- entries and protected procedures are handled because they
19761 -- cannot be directly shared by the two views.
19763 if Is_Concurrent_Type (Full_T) then
19765 Conc_Typ : constant Entity_Id :=
19766 Corresponding_Record_Type (Full_T);
19767 Curr_Nod : Node_Id := Parent (Conc_Typ);
19768 Wrap_Spec : Node_Id;
19771 while Present (Prim_Elmt) loop
19772 Prim := Node (Prim_Elmt);
19774 if Comes_From_Source (Prim)
19775 and then not Is_Abstract_Subprogram (Prim)
19778 Make_Subprogram_Declaration (Sloc (Prim),
19782 Obj_Typ => Conc_Typ,
19784 Parameter_Specifications (
19787 Insert_After (Curr_Nod, Wrap_Spec);
19788 Curr_Nod := Wrap_Spec;
19790 Analyze (Wrap_Spec);
19793 Next_Elmt (Prim_Elmt);
19799 -- For non-concurrent types, transfer explicit primitives, but
19800 -- omit those inherited from the parent of the private view
19801 -- since they will be re-inherited later on.
19804 Full_List := Primitive_Operations (Full_T);
19806 while Present (Prim_Elmt) loop
19807 Prim := Node (Prim_Elmt);
19809 if Comes_From_Source (Prim)
19810 and then not Contains (Prim, Full_List)
19812 Append_Elmt (Prim, Full_List);
19815 Next_Elmt (Prim_Elmt);
19819 -- Untagged private view
19822 Full_List := Primitive_Operations (Full_T);
19824 -- In this case the partial view is untagged, so here we locate
19825 -- all of the earlier primitives that need to be treated as
19826 -- dispatching (those that appear between the two views). Note
19827 -- that these additional operations must all be new operations
19828 -- (any earlier operations that override inherited operations
19829 -- of the full view will already have been inserted in the
19830 -- primitives list, marked by Check_Operation_From_Private_View
19831 -- as dispatching. Note that implicit "/=" operators are
19832 -- excluded from being added to the primitives list since they
19833 -- shouldn't be treated as dispatching (tagged "/=" is handled
19836 Prim := Next_Entity (Full_T);
19837 while Present (Prim) and then Prim /= Priv_T loop
19838 if Ekind_In (Prim, E_Procedure, E_Function) then
19839 Disp_Typ := Find_Dispatching_Type (Prim);
19841 if Disp_Typ = Full_T
19842 and then (Chars (Prim) /= Name_Op_Ne
19843 or else Comes_From_Source (Prim))
19845 Check_Controlling_Formals (Full_T, Prim);
19847 if not Is_Dispatching_Operation (Prim) then
19848 Append_Elmt (Prim, Full_List);
19849 Set_Is_Dispatching_Operation (Prim, True);
19850 Set_DT_Position_Value (Prim, No_Uint);
19853 elsif Is_Dispatching_Operation (Prim)
19854 and then Disp_Typ /= Full_T
19857 -- Verify that it is not otherwise controlled by a
19858 -- formal or a return value of type T.
19860 Check_Controlling_Formals (Disp_Typ, Prim);
19864 Next_Entity (Prim);
19868 -- For the tagged case, the two views can share the same primitive
19869 -- operations list and the same class-wide type. Update attributes
19870 -- of the class-wide type which depend on the full declaration.
19872 if Is_Tagged_Type (Priv_T) then
19873 Set_Direct_Primitive_Operations (Priv_T, Full_List);
19874 Set_Class_Wide_Type
19875 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
19877 Set_Has_Task (Class_Wide_Type (Priv_T), Has_Task (Full_T));
19879 (Class_Wide_Type (Priv_T), Has_Protected (Full_T));
19884 -- Ada 2005 AI 161: Check preelaborable initialization consistency
19886 if Known_To_Have_Preelab_Init (Priv_T) then
19888 -- Case where there is a pragma Preelaborable_Initialization. We
19889 -- always allow this in predefined units, which is cheating a bit,
19890 -- but it means we don't have to struggle to meet the requirements in
19891 -- the RM for having Preelaborable Initialization. Otherwise we
19892 -- require that the type meets the RM rules. But we can't check that
19893 -- yet, because of the rule about overriding Initialize, so we simply
19894 -- set a flag that will be checked at freeze time.
19896 if not In_Predefined_Unit (Full_T) then
19897 Set_Must_Have_Preelab_Init (Full_T);
19901 -- If pragma CPP_Class was applied to the private type declaration,
19902 -- propagate it now to the full type declaration.
19904 if Is_CPP_Class (Priv_T) then
19905 Set_Is_CPP_Class (Full_T);
19906 Set_Convention (Full_T, Convention_CPP);
19908 -- Check that components of imported CPP types do not have default
19911 Check_CPP_Type_Has_No_Defaults (Full_T);
19914 -- If the private view has user specified stream attributes, then so has
19917 -- Why the test, how could these flags be already set in Full_T ???
19919 if Has_Specified_Stream_Read (Priv_T) then
19920 Set_Has_Specified_Stream_Read (Full_T);
19923 if Has_Specified_Stream_Write (Priv_T) then
19924 Set_Has_Specified_Stream_Write (Full_T);
19927 if Has_Specified_Stream_Input (Priv_T) then
19928 Set_Has_Specified_Stream_Input (Full_T);
19931 if Has_Specified_Stream_Output (Priv_T) then
19932 Set_Has_Specified_Stream_Output (Full_T);
19935 -- Propagate the attributes related to pragma Default_Initial_Condition
19936 -- from the private to the full view. Note that both flags are mutually
19939 if Has_Default_Init_Cond (Priv_T)
19940 or else Has_Inherited_Default_Init_Cond (Priv_T)
19942 Propagate_Default_Init_Cond_Attributes
19943 (From_Typ => Priv_T,
19945 Private_To_Full_View => True);
19947 -- In the case where the full view is derived from another private type,
19948 -- the attributes related to pragma Default_Initial_Condition must be
19949 -- propagated from the full to the private view to maintain consistency
19953 -- type Parent_Typ is private
19954 -- with Default_Initial_Condition ...;
19956 -- type Parent_Typ is ...;
19959 -- with Pack; use Pack;
19960 -- package Pack_2 is
19961 -- type Deriv_Typ is private; -- must inherit
19963 -- type Deriv_Typ is new Parent_Typ; -- must inherit
19966 elsif Has_Default_Init_Cond (Full_T)
19967 or else Has_Inherited_Default_Init_Cond (Full_T)
19969 Propagate_Default_Init_Cond_Attributes
19970 (From_Typ => Full_T,
19972 Private_To_Full_View => True);
19975 if Is_Ghost_Entity (Priv_T) then
19977 -- The Ghost policy in effect at the point of declaration and at the
19978 -- point of completion must match (SPARK RM 6.9(14)).
19980 Check_Ghost_Completion (Priv_T, Full_T);
19982 -- In the case where the private view of a tagged type lacks a parent
19983 -- type and is subject to pragma Ghost, ensure that the parent type
19984 -- specified by the full view is also Ghost (SPARK RM 6.9(9)).
19986 if Is_Derived_Type (Full_T) then
19987 Check_Ghost_Derivation (Full_T);
19990 -- Propagate the attributes related to pragma Ghost from the private
19991 -- to the full view.
19993 Mark_Full_View_As_Ghost (Priv_T, Full_T);
19996 -- Propagate invariants to full type
19998 if Has_Invariants (Priv_T) then
19999 Set_Has_Invariants (Full_T);
20000 Set_Invariant_Procedure (Full_T, Invariant_Procedure (Priv_T));
20003 if Has_Inheritable_Invariants (Priv_T) then
20004 Set_Has_Inheritable_Invariants (Full_T);
20007 -- Check hidden inheritance of class-wide type invariants
20009 if Ada_Version >= Ada_2012
20010 and then not Has_Inheritable_Invariants (Full_T)
20011 and then In_Private_Part (Current_Scope)
20012 and then Has_Interfaces (Full_T)
20019 Collect_Interfaces (Full_T, Ifaces, Exclude_Parents => True);
20021 AI := First_Elmt (Ifaces);
20022 while Present (AI) loop
20023 if Has_Inheritable_Invariants (Node (AI)) then
20025 ("hidden inheritance of class-wide type invariants " &
20035 -- Propagate predicates to full type, and predicate function if already
20036 -- defined. It is not clear that this can actually happen? the partial
20037 -- view cannot be frozen yet, and the predicate function has not been
20038 -- built. Still it is a cheap check and seems safer to make it.
20040 if Has_Predicates (Priv_T) then
20041 if Present (Predicate_Function (Priv_T)) then
20042 Set_Predicate_Function (Full_T, Predicate_Function (Priv_T));
20045 Set_Has_Predicates (Full_T);
20047 end Process_Full_View;
20049 -----------------------------------
20050 -- Process_Incomplete_Dependents --
20051 -----------------------------------
20053 procedure Process_Incomplete_Dependents
20055 Full_T : Entity_Id;
20058 Inc_Elmt : Elmt_Id;
20059 Priv_Dep : Entity_Id;
20060 New_Subt : Entity_Id;
20062 Disc_Constraint : Elist_Id;
20065 if No (Private_Dependents (Inc_T)) then
20069 -- Itypes that may be generated by the completion of an incomplete
20070 -- subtype are not used by the back-end and not attached to the tree.
20071 -- They are created only for constraint-checking purposes.
20073 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
20074 while Present (Inc_Elmt) loop
20075 Priv_Dep := Node (Inc_Elmt);
20077 if Ekind (Priv_Dep) = E_Subprogram_Type then
20079 -- An Access_To_Subprogram type may have a return type or a
20080 -- parameter type that is incomplete. Replace with the full view.
20082 if Etype (Priv_Dep) = Inc_T then
20083 Set_Etype (Priv_Dep, Full_T);
20087 Formal : Entity_Id;
20090 Formal := First_Formal (Priv_Dep);
20091 while Present (Formal) loop
20092 if Etype (Formal) = Inc_T then
20093 Set_Etype (Formal, Full_T);
20096 Next_Formal (Formal);
20100 elsif Is_Overloadable (Priv_Dep) then
20102 -- If a subprogram in the incomplete dependents list is primitive
20103 -- for a tagged full type then mark it as a dispatching operation,
20104 -- check whether it overrides an inherited subprogram, and check
20105 -- restrictions on its controlling formals. Note that a protected
20106 -- operation is never dispatching: only its wrapper operation
20107 -- (which has convention Ada) is.
20109 if Is_Tagged_Type (Full_T)
20110 and then Is_Primitive (Priv_Dep)
20111 and then Convention (Priv_Dep) /= Convention_Protected
20113 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
20114 Set_Is_Dispatching_Operation (Priv_Dep);
20115 Check_Controlling_Formals (Full_T, Priv_Dep);
20118 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
20120 -- Can happen during processing of a body before the completion
20121 -- of a TA type. Ignore, because spec is also on dependent list.
20125 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
20126 -- corresponding subtype of the full view.
20128 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype then
20129 Set_Subtype_Indication
20130 (Parent (Priv_Dep), New_Occurrence_Of (Full_T, Sloc (Priv_Dep)));
20131 Set_Etype (Priv_Dep, Full_T);
20132 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
20133 Set_Analyzed (Parent (Priv_Dep), False);
20135 -- Reanalyze the declaration, suppressing the call to
20136 -- Enter_Name to avoid duplicate names.
20138 Analyze_Subtype_Declaration
20139 (N => Parent (Priv_Dep),
20142 -- Dependent is a subtype
20145 -- We build a new subtype indication using the full view of the
20146 -- incomplete parent. The discriminant constraints have been
20147 -- elaborated already at the point of the subtype declaration.
20149 New_Subt := Create_Itype (E_Void, N);
20151 if Has_Discriminants (Full_T) then
20152 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
20154 Disc_Constraint := No_Elist;
20157 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
20158 Set_Full_View (Priv_Dep, New_Subt);
20161 Next_Elmt (Inc_Elmt);
20163 end Process_Incomplete_Dependents;
20165 --------------------------------
20166 -- Process_Range_Expr_In_Decl --
20167 --------------------------------
20169 procedure Process_Range_Expr_In_Decl
20172 Subtyp : Entity_Id := Empty;
20173 Check_List : List_Id := Empty_List;
20174 R_Check_Off : Boolean := False;
20175 In_Iter_Schm : Boolean := False)
20178 R_Checks : Check_Result;
20179 Insert_Node : Node_Id;
20180 Def_Id : Entity_Id;
20183 Analyze_And_Resolve (R, Base_Type (T));
20185 if Nkind (R) = N_Range then
20187 -- In SPARK, all ranges should be static, with the exception of the
20188 -- discrete type definition of a loop parameter specification.
20190 if not In_Iter_Schm
20191 and then not Is_OK_Static_Range (R)
20193 Check_SPARK_05_Restriction ("range should be static", R);
20196 Lo := Low_Bound (R);
20197 Hi := High_Bound (R);
20199 -- Validity checks on the range of a quantified expression are
20200 -- delayed until the construct is transformed into a loop.
20202 if Nkind (Parent (R)) = N_Loop_Parameter_Specification
20203 and then Nkind (Parent (Parent (R))) = N_Quantified_Expression
20207 -- We need to ensure validity of the bounds here, because if we
20208 -- go ahead and do the expansion, then the expanded code will get
20209 -- analyzed with range checks suppressed and we miss the check.
20211 -- WARNING: The capture of the range bounds with xxx_FIRST/_LAST and
20212 -- the temporaries generated by routine Remove_Side_Effects by means
20213 -- of validity checks must use the same names. When a range appears
20214 -- in the parent of a generic, the range is processed with checks
20215 -- disabled as part of the generic context and with checks enabled
20216 -- for code generation purposes. This leads to link issues as the
20217 -- generic contains references to xxx_FIRST/_LAST, but the inlined
20218 -- template sees the temporaries generated by Remove_Side_Effects.
20221 Validity_Check_Range (R, Subtyp);
20224 -- If there were errors in the declaration, try and patch up some
20225 -- common mistakes in the bounds. The cases handled are literals
20226 -- which are Integer where the expected type is Real and vice versa.
20227 -- These corrections allow the compilation process to proceed further
20228 -- along since some basic assumptions of the format of the bounds
20231 if Etype (R) = Any_Type then
20232 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
20234 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
20236 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
20238 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
20240 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
20242 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
20244 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
20246 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
20253 -- If the bounds of the range have been mistakenly given as string
20254 -- literals (perhaps in place of character literals), then an error
20255 -- has already been reported, but we rewrite the string literal as a
20256 -- bound of the range's type to avoid blowups in later processing
20257 -- that looks at static values.
20259 if Nkind (Lo) = N_String_Literal then
20261 Make_Attribute_Reference (Sloc (Lo),
20262 Prefix => New_Occurrence_Of (T, Sloc (Lo)),
20263 Attribute_Name => Name_First));
20264 Analyze_And_Resolve (Lo);
20267 if Nkind (Hi) = N_String_Literal then
20269 Make_Attribute_Reference (Sloc (Hi),
20270 Prefix => New_Occurrence_Of (T, Sloc (Hi)),
20271 Attribute_Name => Name_First));
20272 Analyze_And_Resolve (Hi);
20275 -- If bounds aren't scalar at this point then exit, avoiding
20276 -- problems with further processing of the range in this procedure.
20278 if not Is_Scalar_Type (Etype (Lo)) then
20282 -- Resolve (actually Sem_Eval) has checked that the bounds are in
20283 -- then range of the base type. Here we check whether the bounds
20284 -- are in the range of the subtype itself. Note that if the bounds
20285 -- represent the null range the Constraint_Error exception should
20288 -- ??? The following code should be cleaned up as follows
20290 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
20291 -- is done in the call to Range_Check (R, T); below
20293 -- 2. The use of R_Check_Off should be investigated and possibly
20294 -- removed, this would clean up things a bit.
20296 if Is_Null_Range (Lo, Hi) then
20300 -- Capture values of bounds and generate temporaries for them
20301 -- if needed, before applying checks, since checks may cause
20302 -- duplication of the expression without forcing evaluation.
20304 -- The forced evaluation removes side effects from expressions,
20305 -- which should occur also in GNATprove mode. Otherwise, we end up
20306 -- with unexpected insertions of actions at places where this is
20307 -- not supposed to occur, e.g. on default parameters of a call.
20309 if Expander_Active or GNATprove_Mode then
20311 -- Call Force_Evaluation to create declarations as needed to
20312 -- deal with side effects, and also create typ_FIRST/LAST
20313 -- entities for bounds if we have a subtype name.
20315 -- Note: we do this transformation even if expansion is not
20316 -- active if we are in GNATprove_Mode since the transformation
20317 -- is in general required to ensure that the resulting tree has
20318 -- proper Ada semantics.
20321 (Lo, Related_Id => Subtyp, Is_Low_Bound => True);
20323 (Hi, Related_Id => Subtyp, Is_High_Bound => True);
20326 -- We use a flag here instead of suppressing checks on the type
20327 -- because the type we check against isn't necessarily the place
20328 -- where we put the check.
20330 if not R_Check_Off then
20331 R_Checks := Get_Range_Checks (R, T);
20333 -- Look up tree to find an appropriate insertion point. We
20334 -- can't just use insert_actions because later processing
20335 -- depends on the insertion node. Prior to Ada 2012 the
20336 -- insertion point could only be a declaration or a loop, but
20337 -- quantified expressions can appear within any context in an
20338 -- expression, and the insertion point can be any statement,
20339 -- pragma, or declaration.
20341 Insert_Node := Parent (R);
20342 while Present (Insert_Node) loop
20344 Nkind (Insert_Node) in N_Declaration
20347 (Insert_Node, N_Component_Declaration,
20348 N_Loop_Parameter_Specification,
20349 N_Function_Specification,
20350 N_Procedure_Specification);
20352 exit when Nkind (Insert_Node) in N_Later_Decl_Item
20353 or else Nkind (Insert_Node) in
20354 N_Statement_Other_Than_Procedure_Call
20355 or else Nkind_In (Insert_Node, N_Procedure_Call_Statement,
20358 Insert_Node := Parent (Insert_Node);
20361 -- Why would Type_Decl not be present??? Without this test,
20362 -- short regression tests fail.
20364 if Present (Insert_Node) then
20366 -- Case of loop statement. Verify that the range is part
20367 -- of the subtype indication of the iteration scheme.
20369 if Nkind (Insert_Node) = N_Loop_Statement then
20374 Indic := Parent (R);
20375 while Present (Indic)
20376 and then Nkind (Indic) /= N_Subtype_Indication
20378 Indic := Parent (Indic);
20381 if Present (Indic) then
20382 Def_Id := Etype (Subtype_Mark (Indic));
20384 Insert_Range_Checks
20388 Sloc (Insert_Node),
20390 Do_Before => True);
20394 -- Insertion before a declaration. If the declaration
20395 -- includes discriminants, the list of applicable checks
20396 -- is given by the caller.
20398 elsif Nkind (Insert_Node) in N_Declaration then
20399 Def_Id := Defining_Identifier (Insert_Node);
20401 if (Ekind (Def_Id) = E_Record_Type
20402 and then Depends_On_Discriminant (R))
20404 (Ekind (Def_Id) = E_Protected_Type
20405 and then Has_Discriminants (Def_Id))
20407 Append_Range_Checks
20409 Check_List, Def_Id, Sloc (Insert_Node), R);
20412 Insert_Range_Checks
20414 Insert_Node, Def_Id, Sloc (Insert_Node), R);
20418 -- Insertion before a statement. Range appears in the
20419 -- context of a quantified expression. Insertion will
20420 -- take place when expression is expanded.
20429 -- Case of other than an explicit N_Range node
20431 -- The forced evaluation removes side effects from expressions, which
20432 -- should occur also in GNATprove mode. Otherwise, we end up with
20433 -- unexpected insertions of actions at places where this is not
20434 -- supposed to occur, e.g. on default parameters of a call.
20436 elsif Expander_Active or GNATprove_Mode then
20437 Get_Index_Bounds (R, Lo, Hi);
20438 Force_Evaluation (Lo);
20439 Force_Evaluation (Hi);
20441 end Process_Range_Expr_In_Decl;
20443 --------------------------------------
20444 -- Process_Real_Range_Specification --
20445 --------------------------------------
20447 procedure Process_Real_Range_Specification (Def : Node_Id) is
20448 Spec : constant Node_Id := Real_Range_Specification (Def);
20451 Err : Boolean := False;
20453 procedure Analyze_Bound (N : Node_Id);
20454 -- Analyze and check one bound
20456 -------------------
20457 -- Analyze_Bound --
20458 -------------------
20460 procedure Analyze_Bound (N : Node_Id) is
20462 Analyze_And_Resolve (N, Any_Real);
20464 if not Is_OK_Static_Expression (N) then
20465 Flag_Non_Static_Expr
20466 ("bound in real type definition is not static!", N);
20471 -- Start of processing for Process_Real_Range_Specification
20474 if Present (Spec) then
20475 Lo := Low_Bound (Spec);
20476 Hi := High_Bound (Spec);
20477 Analyze_Bound (Lo);
20478 Analyze_Bound (Hi);
20480 -- If error, clear away junk range specification
20483 Set_Real_Range_Specification (Def, Empty);
20486 end Process_Real_Range_Specification;
20488 ---------------------
20489 -- Process_Subtype --
20490 ---------------------
20492 function Process_Subtype
20494 Related_Nod : Node_Id;
20495 Related_Id : Entity_Id := Empty;
20496 Suffix : Character := ' ') return Entity_Id
20499 Def_Id : Entity_Id;
20500 Error_Node : Node_Id;
20501 Full_View_Id : Entity_Id;
20502 Subtype_Mark_Id : Entity_Id;
20504 May_Have_Null_Exclusion : Boolean;
20506 procedure Check_Incomplete (T : Entity_Id);
20507 -- Called to verify that an incomplete type is not used prematurely
20509 ----------------------
20510 -- Check_Incomplete --
20511 ----------------------
20513 procedure Check_Incomplete (T : Entity_Id) is
20515 -- Ada 2005 (AI-412): Incomplete subtypes are legal
20517 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
20519 not (Ada_Version >= Ada_2005
20521 (Nkind (Parent (T)) = N_Subtype_Declaration
20522 or else (Nkind (Parent (T)) = N_Subtype_Indication
20523 and then Nkind (Parent (Parent (T))) =
20524 N_Subtype_Declaration)))
20526 Error_Msg_N ("invalid use of type before its full declaration", T);
20528 end Check_Incomplete;
20530 -- Start of processing for Process_Subtype
20533 -- Case of no constraints present
20535 if Nkind (S) /= N_Subtype_Indication then
20537 Check_Incomplete (S);
20540 -- Ada 2005 (AI-231): Static check
20542 if Ada_Version >= Ada_2005
20543 and then Present (P)
20544 and then Null_Exclusion_Present (P)
20545 and then Nkind (P) /= N_Access_To_Object_Definition
20546 and then not Is_Access_Type (Entity (S))
20548 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
20551 -- The following is ugly, can't we have a range or even a flag???
20553 May_Have_Null_Exclusion :=
20554 Nkind_In (P, N_Access_Definition,
20555 N_Access_Function_Definition,
20556 N_Access_Procedure_Definition,
20557 N_Access_To_Object_Definition,
20559 N_Component_Definition)
20561 Nkind_In (P, N_Derived_Type_Definition,
20562 N_Discriminant_Specification,
20563 N_Formal_Object_Declaration,
20564 N_Object_Declaration,
20565 N_Object_Renaming_Declaration,
20566 N_Parameter_Specification,
20567 N_Subtype_Declaration);
20569 -- Create an Itype that is a duplicate of Entity (S) but with the
20570 -- null-exclusion attribute.
20572 if May_Have_Null_Exclusion
20573 and then Is_Access_Type (Entity (S))
20574 and then Null_Exclusion_Present (P)
20576 -- No need to check the case of an access to object definition.
20577 -- It is correct to define double not-null pointers.
20580 -- type Not_Null_Int_Ptr is not null access Integer;
20581 -- type Acc is not null access Not_Null_Int_Ptr;
20583 and then Nkind (P) /= N_Access_To_Object_Definition
20585 if Can_Never_Be_Null (Entity (S)) then
20586 case Nkind (Related_Nod) is
20587 when N_Full_Type_Declaration =>
20588 if Nkind (Type_Definition (Related_Nod))
20589 in N_Array_Type_Definition
20593 (Component_Definition
20594 (Type_Definition (Related_Nod)));
20597 Subtype_Indication (Type_Definition (Related_Nod));
20600 when N_Subtype_Declaration =>
20601 Error_Node := Subtype_Indication (Related_Nod);
20603 when N_Object_Declaration =>
20604 Error_Node := Object_Definition (Related_Nod);
20606 when N_Component_Declaration =>
20608 Subtype_Indication (Component_Definition (Related_Nod));
20610 when N_Allocator =>
20611 Error_Node := Expression (Related_Nod);
20614 pragma Assert (False);
20615 Error_Node := Related_Nod;
20619 ("`NOT NULL` not allowed (& already excludes null)",
20625 Create_Null_Excluding_Itype
20627 Related_Nod => P));
20628 Set_Entity (S, Etype (S));
20633 -- Case of constraint present, so that we have an N_Subtype_Indication
20634 -- node (this node is created only if constraints are present).
20637 Find_Type (Subtype_Mark (S));
20639 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
20641 (Nkind (Parent (S)) = N_Subtype_Declaration
20642 and then Is_Itype (Defining_Identifier (Parent (S))))
20644 Check_Incomplete (Subtype_Mark (S));
20648 Subtype_Mark_Id := Entity (Subtype_Mark (S));
20650 -- Explicit subtype declaration case
20652 if Nkind (P) = N_Subtype_Declaration then
20653 Def_Id := Defining_Identifier (P);
20655 -- Explicit derived type definition case
20657 elsif Nkind (P) = N_Derived_Type_Definition then
20658 Def_Id := Defining_Identifier (Parent (P));
20660 -- Implicit case, the Def_Id must be created as an implicit type.
20661 -- The one exception arises in the case of concurrent types, array
20662 -- and access types, where other subsidiary implicit types may be
20663 -- created and must appear before the main implicit type. In these
20664 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
20665 -- has not yet been called to create Def_Id.
20668 if Is_Array_Type (Subtype_Mark_Id)
20669 or else Is_Concurrent_Type (Subtype_Mark_Id)
20670 or else Is_Access_Type (Subtype_Mark_Id)
20674 -- For the other cases, we create a new unattached Itype,
20675 -- and set the indication to ensure it gets attached later.
20679 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
20683 -- If the kind of constraint is invalid for this kind of type,
20684 -- then give an error, and then pretend no constraint was given.
20686 if not Is_Valid_Constraint_Kind
20687 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
20690 ("incorrect constraint for this kind of type", Constraint (S));
20692 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
20694 -- Set Ekind of orphan itype, to prevent cascaded errors
20696 if Present (Def_Id) then
20697 Set_Ekind (Def_Id, Ekind (Any_Type));
20700 -- Make recursive call, having got rid of the bogus constraint
20702 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
20705 -- Remaining processing depends on type. Select on Base_Type kind to
20706 -- ensure getting to the concrete type kind in the case of a private
20707 -- subtype (needed when only doing semantic analysis).
20709 case Ekind (Base_Type (Subtype_Mark_Id)) is
20710 when Access_Kind =>
20712 -- If this is a constraint on a class-wide type, discard it.
20713 -- There is currently no way to express a partial discriminant
20714 -- constraint on a type with unknown discriminants. This is
20715 -- a pathology that the ACATS wisely decides not to test.
20717 if Is_Class_Wide_Type (Designated_Type (Subtype_Mark_Id)) then
20718 if Comes_From_Source (S) then
20720 ("constraint on class-wide type ignored??",
20724 if Nkind (P) = N_Subtype_Declaration then
20725 Set_Subtype_Indication (P,
20726 New_Occurrence_Of (Subtype_Mark_Id, Sloc (S)));
20729 return Subtype_Mark_Id;
20732 Constrain_Access (Def_Id, S, Related_Nod);
20735 and then Is_Itype (Designated_Type (Def_Id))
20736 and then Nkind (Related_Nod) = N_Subtype_Declaration
20737 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
20739 Build_Itype_Reference
20740 (Designated_Type (Def_Id), Related_Nod);
20744 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
20746 when Decimal_Fixed_Point_Kind =>
20747 Constrain_Decimal (Def_Id, S);
20749 when Enumeration_Kind =>
20750 Constrain_Enumeration (Def_Id, S);
20751 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
20753 when Ordinary_Fixed_Point_Kind =>
20754 Constrain_Ordinary_Fixed (Def_Id, S);
20757 Constrain_Float (Def_Id, S);
20759 when Integer_Kind =>
20760 Constrain_Integer (Def_Id, S);
20761 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
20763 when E_Record_Type |
20766 E_Incomplete_Type =>
20767 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
20769 if Ekind (Def_Id) = E_Incomplete_Type then
20770 Set_Private_Dependents (Def_Id, New_Elmt_List);
20773 when Private_Kind =>
20774 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
20775 Set_Private_Dependents (Def_Id, New_Elmt_List);
20777 -- In case of an invalid constraint prevent further processing
20778 -- since the type constructed is missing expected fields.
20780 if Etype (Def_Id) = Any_Type then
20784 -- If the full view is that of a task with discriminants,
20785 -- we must constrain both the concurrent type and its
20786 -- corresponding record type. Otherwise we will just propagate
20787 -- the constraint to the full view, if available.
20789 if Present (Full_View (Subtype_Mark_Id))
20790 and then Has_Discriminants (Subtype_Mark_Id)
20791 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
20794 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
20796 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
20797 Constrain_Concurrent (Full_View_Id, S,
20798 Related_Nod, Related_Id, Suffix);
20799 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
20800 Set_Full_View (Def_Id, Full_View_Id);
20802 -- Introduce an explicit reference to the private subtype,
20803 -- to prevent scope anomalies in gigi if first use appears
20804 -- in a nested context, e.g. a later function body.
20805 -- Should this be generated in other contexts than a full
20806 -- type declaration?
20808 if Is_Itype (Def_Id)
20810 Nkind (Parent (P)) = N_Full_Type_Declaration
20812 Build_Itype_Reference (Def_Id, Parent (P));
20816 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
20819 when Concurrent_Kind =>
20820 Constrain_Concurrent (Def_Id, S,
20821 Related_Nod, Related_Id, Suffix);
20824 Error_Msg_N ("invalid subtype mark in subtype indication", S);
20827 -- Size and Convention are always inherited from the base type
20829 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
20830 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
20834 end Process_Subtype;
20836 --------------------------------------------
20837 -- Propagate_Default_Init_Cond_Attributes --
20838 --------------------------------------------
20840 procedure Propagate_Default_Init_Cond_Attributes
20841 (From_Typ : Entity_Id;
20842 To_Typ : Entity_Id;
20843 Parent_To_Derivation : Boolean := False;
20844 Private_To_Full_View : Boolean := False)
20846 procedure Remove_Default_Init_Cond_Procedure (Typ : Entity_Id);
20847 -- Remove the default initial procedure (if any) from the rep chain of
20850 ----------------------------------------
20851 -- Remove_Default_Init_Cond_Procedure --
20852 ----------------------------------------
20854 procedure Remove_Default_Init_Cond_Procedure (Typ : Entity_Id) is
20855 Found : Boolean := False;
20861 Subp := Subprograms_For_Type (Typ);
20862 while Present (Subp) loop
20863 if Is_Default_Init_Cond_Procedure (Subp) then
20869 Subp := Subprograms_For_Type (Subp);
20873 Set_Subprograms_For_Type (Prev, Subprograms_For_Type (Subp));
20874 Set_Subprograms_For_Type (Subp, Empty);
20876 end Remove_Default_Init_Cond_Procedure;
20880 Inherit_Procedure : Boolean := False;
20882 -- Start of processing for Propagate_Default_Init_Cond_Attributes
20885 if Has_Default_Init_Cond (From_Typ) then
20887 -- A derived type inherits the attributes from its parent type
20889 if Parent_To_Derivation then
20890 Set_Has_Inherited_Default_Init_Cond (To_Typ);
20892 -- A full view shares the attributes with its private view
20895 Set_Has_Default_Init_Cond (To_Typ);
20898 Inherit_Procedure := True;
20900 -- Due to the order of expansion, a derived private type is processed
20901 -- by two routines which both attempt to set the attributes related
20902 -- to pragma Default_Initial_Condition - Build_Derived_Type and then
20903 -- Process_Full_View.
20906 -- type Parent_Typ is private
20907 -- with Default_Initial_Condition ...;
20909 -- type Parent_Typ is ...;
20912 -- with Pack; use Pack;
20913 -- package Pack_2 is
20914 -- type Deriv_Typ is private
20915 -- with Default_Initial_Condition ...;
20917 -- type Deriv_Typ is new Parent_Typ;
20920 -- When Build_Derived_Type operates, it sets the attributes on the
20921 -- full view without taking into account that the private view may
20922 -- define its own default initial condition procedure. This becomes
20923 -- apparent in Process_Full_View which must undo some of the work by
20924 -- Build_Derived_Type and propagate the attributes from the private
20925 -- to the full view.
20927 if Private_To_Full_View then
20928 Set_Has_Inherited_Default_Init_Cond (To_Typ, False);
20929 Remove_Default_Init_Cond_Procedure (To_Typ);
20932 -- A type must inherit the default initial condition procedure from a
20933 -- parent type when the parent itself is inheriting the procedure or
20934 -- when it is defining one. This circuitry is also used when dealing
20935 -- with the private / full view of a type.
20937 elsif Has_Inherited_Default_Init_Cond (From_Typ)
20938 or (Parent_To_Derivation
20939 and Present (Get_Pragma
20940 (From_Typ, Pragma_Default_Initial_Condition)))
20942 Set_Has_Inherited_Default_Init_Cond (To_Typ);
20943 Inherit_Procedure := True;
20946 if Inherit_Procedure
20947 and then No (Default_Init_Cond_Procedure (To_Typ))
20949 Set_Default_Init_Cond_Procedure
20950 (To_Typ, Default_Init_Cond_Procedure (From_Typ));
20952 end Propagate_Default_Init_Cond_Attributes;
20954 -----------------------------
20955 -- Record_Type_Declaration --
20956 -----------------------------
20958 procedure Record_Type_Declaration
20963 Def : constant Node_Id := Type_Definition (N);
20964 Is_Tagged : Boolean;
20965 Tag_Comp : Entity_Id;
20968 -- These flags must be initialized before calling Process_Discriminants
20969 -- because this routine makes use of them.
20971 Set_Ekind (T, E_Record_Type);
20973 Init_Size_Align (T);
20974 Set_Interfaces (T, No_Elist);
20975 Set_Stored_Constraint (T, No_Elist);
20976 Set_Default_SSO (T);
20980 if Ada_Version < Ada_2005 or else not Interface_Present (Def) then
20981 if Limited_Present (Def) then
20982 Check_SPARK_05_Restriction ("limited is not allowed", N);
20985 if Abstract_Present (Def) then
20986 Check_SPARK_05_Restriction ("abstract is not allowed", N);
20989 -- The flag Is_Tagged_Type might have already been set by
20990 -- Find_Type_Name if it detected an error for declaration T. This
20991 -- arises in the case of private tagged types where the full view
20992 -- omits the word tagged.
20995 Tagged_Present (Def)
20996 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
20998 Set_Is_Limited_Record (T, Limited_Present (Def));
21001 Set_Is_Tagged_Type (T, True);
21002 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
21005 -- Type is abstract if full declaration carries keyword, or if
21006 -- previous partial view did.
21008 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
21009 or else Abstract_Present (Def));
21012 Check_SPARK_05_Restriction ("interface is not allowed", N);
21015 Analyze_Interface_Declaration (T, Def);
21017 if Present (Discriminant_Specifications (N)) then
21019 ("interface types cannot have discriminants",
21020 Defining_Identifier
21021 (First (Discriminant_Specifications (N))));
21025 -- First pass: if there are self-referential access components,
21026 -- create the required anonymous access type declarations, and if
21027 -- need be an incomplete type declaration for T itself.
21029 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
21031 if Ada_Version >= Ada_2005
21032 and then Present (Interface_List (Def))
21034 Check_Interfaces (N, Def);
21037 Ifaces_List : Elist_Id;
21040 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
21041 -- already in the parents.
21045 Ifaces_List => Ifaces_List,
21046 Exclude_Parents => True);
21048 Set_Interfaces (T, Ifaces_List);
21052 -- Records constitute a scope for the component declarations within.
21053 -- The scope is created prior to the processing of these declarations.
21054 -- Discriminants are processed first, so that they are visible when
21055 -- processing the other components. The Ekind of the record type itself
21056 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
21058 -- Enter record scope
21062 -- If an incomplete or private type declaration was already given for
21063 -- the type, then this scope already exists, and the discriminants have
21064 -- been declared within. We must verify that the full declaration
21065 -- matches the incomplete one.
21067 Check_Or_Process_Discriminants (N, T, Prev);
21069 Set_Is_Constrained (T, not Has_Discriminants (T));
21070 Set_Has_Delayed_Freeze (T, True);
21072 -- For tagged types add a manually analyzed component corresponding
21073 -- to the component _tag, the corresponding piece of tree will be
21074 -- expanded as part of the freezing actions if it is not a CPP_Class.
21078 -- Do not add the tag unless we are in expansion mode
21080 if Expander_Active then
21081 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
21082 Enter_Name (Tag_Comp);
21084 Set_Ekind (Tag_Comp, E_Component);
21085 Set_Is_Tag (Tag_Comp);
21086 Set_Is_Aliased (Tag_Comp);
21087 Set_Etype (Tag_Comp, RTE (RE_Tag));
21088 Set_DT_Entry_Count (Tag_Comp, No_Uint);
21089 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
21090 Init_Component_Location (Tag_Comp);
21092 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
21093 -- implemented interfaces.
21095 if Has_Interfaces (T) then
21096 Add_Interface_Tag_Components (N, T);
21100 Make_Class_Wide_Type (T);
21101 Set_Direct_Primitive_Operations (T, New_Elmt_List);
21104 -- We must suppress range checks when processing record components in
21105 -- the presence of discriminants, since we don't want spurious checks to
21106 -- be generated during their analysis, but Suppress_Range_Checks flags
21107 -- must be reset the after processing the record definition.
21109 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
21110 -- couldn't we just use the normal range check suppression method here.
21111 -- That would seem cleaner ???
21113 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
21114 Set_Kill_Range_Checks (T, True);
21115 Record_Type_Definition (Def, Prev);
21116 Set_Kill_Range_Checks (T, False);
21118 Record_Type_Definition (Def, Prev);
21121 -- Exit from record scope
21125 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
21126 -- the implemented interfaces and associate them an aliased entity.
21129 and then not Is_Empty_List (Interface_List (Def))
21131 Derive_Progenitor_Subprograms (T, T);
21134 Check_Function_Writable_Actuals (N);
21135 end Record_Type_Declaration;
21137 ----------------------------
21138 -- Record_Type_Definition --
21139 ----------------------------
21141 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
21142 Component : Entity_Id;
21143 Ctrl_Components : Boolean := False;
21144 Final_Storage_Only : Boolean;
21148 if Ekind (Prev_T) = E_Incomplete_Type then
21149 T := Full_View (Prev_T);
21154 -- In SPARK, tagged types and type extensions may only be declared in
21155 -- the specification of library unit packages.
21157 if Present (Def) and then Is_Tagged_Type (T) then
21163 if Nkind (Parent (Def)) = N_Full_Type_Declaration then
21164 Typ := Parent (Def);
21167 (Nkind (Parent (Def)) = N_Derived_Type_Definition);
21168 Typ := Parent (Parent (Def));
21171 Ctxt := Parent (Typ);
21173 if Nkind (Ctxt) = N_Package_Body
21174 and then Nkind (Parent (Ctxt)) = N_Compilation_Unit
21176 Check_SPARK_05_Restriction
21177 ("type should be defined in package specification", Typ);
21179 elsif Nkind (Ctxt) /= N_Package_Specification
21180 or else Nkind (Parent (Parent (Ctxt))) /= N_Compilation_Unit
21182 Check_SPARK_05_Restriction
21183 ("type should be defined in library unit package", Typ);
21188 Final_Storage_Only := not Is_Controlled_Active (T);
21190 -- Ada 2005: Check whether an explicit Limited is present in a derived
21191 -- type declaration.
21193 if Nkind (Parent (Def)) = N_Derived_Type_Definition
21194 and then Limited_Present (Parent (Def))
21196 Set_Is_Limited_Record (T);
21199 -- If the component list of a record type is defined by the reserved
21200 -- word null and there is no discriminant part, then the record type has
21201 -- no components and all records of the type are null records (RM 3.7)
21202 -- This procedure is also called to process the extension part of a
21203 -- record extension, in which case the current scope may have inherited
21207 or else No (Component_List (Def))
21208 or else Null_Present (Component_List (Def))
21210 if not Is_Tagged_Type (T) then
21211 Check_SPARK_05_Restriction ("untagged record cannot be null", Def);
21215 Analyze_Declarations (Component_Items (Component_List (Def)));
21217 if Present (Variant_Part (Component_List (Def))) then
21218 Check_SPARK_05_Restriction ("variant part is not allowed", Def);
21219 Analyze (Variant_Part (Component_List (Def)));
21223 -- After completing the semantic analysis of the record definition,
21224 -- record components, both new and inherited, are accessible. Set their
21225 -- kind accordingly. Exclude malformed itypes from illegal declarations,
21226 -- whose Ekind may be void.
21228 Component := First_Entity (Current_Scope);
21229 while Present (Component) loop
21230 if Ekind (Component) = E_Void
21231 and then not Is_Itype (Component)
21233 Set_Ekind (Component, E_Component);
21234 Init_Component_Location (Component);
21237 if Has_Task (Etype (Component)) then
21241 if Has_Protected (Etype (Component)) then
21242 Set_Has_Protected (T);
21245 if Ekind (Component) /= E_Component then
21248 -- Do not set Has_Controlled_Component on a class-wide equivalent
21249 -- type. See Make_CW_Equivalent_Type.
21251 elsif not Is_Class_Wide_Equivalent_Type (T)
21252 and then (Has_Controlled_Component (Etype (Component))
21253 or else (Chars (Component) /= Name_uParent
21254 and then Is_Controlled_Active
21255 (Etype (Component))))
21257 Set_Has_Controlled_Component (T, True);
21258 Final_Storage_Only :=
21260 and then Finalize_Storage_Only (Etype (Component));
21261 Ctrl_Components := True;
21264 Next_Entity (Component);
21267 -- A Type is Finalize_Storage_Only only if all its controlled components
21270 if Ctrl_Components then
21271 Set_Finalize_Storage_Only (T, Final_Storage_Only);
21274 -- Place reference to end record on the proper entity, which may
21275 -- be a partial view.
21277 if Present (Def) then
21278 Process_End_Label (Def, 'e', Prev_T);
21280 end Record_Type_Definition;
21282 ------------------------
21283 -- Replace_Components --
21284 ------------------------
21286 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
21287 function Process (N : Node_Id) return Traverse_Result;
21293 function Process (N : Node_Id) return Traverse_Result is
21297 if Nkind (N) = N_Discriminant_Specification then
21298 Comp := First_Discriminant (Typ);
21299 while Present (Comp) loop
21300 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21301 Set_Defining_Identifier (N, Comp);
21305 Next_Discriminant (Comp);
21308 elsif Nkind (N) = N_Component_Declaration then
21309 Comp := First_Component (Typ);
21310 while Present (Comp) loop
21311 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21312 Set_Defining_Identifier (N, Comp);
21316 Next_Component (Comp);
21323 procedure Replace is new Traverse_Proc (Process);
21325 -- Start of processing for Replace_Components
21329 end Replace_Components;
21331 -------------------------------
21332 -- Set_Completion_Referenced --
21333 -------------------------------
21335 procedure Set_Completion_Referenced (E : Entity_Id) is
21337 -- If in main unit, mark entity that is a completion as referenced,
21338 -- warnings go on the partial view when needed.
21340 if In_Extended_Main_Source_Unit (E) then
21341 Set_Referenced (E);
21343 end Set_Completion_Referenced;
21345 ---------------------
21346 -- Set_Default_SSO --
21347 ---------------------
21349 procedure Set_Default_SSO (T : Entity_Id) is
21351 case Opt.Default_SSO is
21355 Set_SSO_Set_Low_By_Default (T, True);
21357 Set_SSO_Set_High_By_Default (T, True);
21359 raise Program_Error;
21361 end Set_Default_SSO;
21363 ---------------------
21364 -- Set_Fixed_Range --
21365 ---------------------
21367 -- The range for fixed-point types is complicated by the fact that we
21368 -- do not know the exact end points at the time of the declaration. This
21369 -- is true for three reasons:
21371 -- A size clause may affect the fudging of the end-points.
21372 -- A small clause may affect the values of the end-points.
21373 -- We try to include the end-points if it does not affect the size.
21375 -- This means that the actual end-points must be established at the
21376 -- point when the type is frozen. Meanwhile, we first narrow the range
21377 -- as permitted (so that it will fit if necessary in a small specified
21378 -- size), and then build a range subtree with these narrowed bounds.
21379 -- Set_Fixed_Range constructs the range from real literal values, and
21380 -- sets the range as the Scalar_Range of the given fixed-point type entity.
21382 -- The parent of this range is set to point to the entity so that it is
21383 -- properly hooked into the tree (unlike normal Scalar_Range entries for
21384 -- other scalar types, which are just pointers to the range in the
21385 -- original tree, this would otherwise be an orphan).
21387 -- The tree is left unanalyzed. When the type is frozen, the processing
21388 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
21389 -- analyzed, and uses this as an indication that it should complete
21390 -- work on the range (it will know the final small and size values).
21392 procedure Set_Fixed_Range
21398 S : constant Node_Id :=
21400 Low_Bound => Make_Real_Literal (Loc, Lo),
21401 High_Bound => Make_Real_Literal (Loc, Hi));
21403 Set_Scalar_Range (E, S);
21406 -- Before the freeze point, the bounds of a fixed point are universal
21407 -- and carry the corresponding type.
21409 Set_Etype (Low_Bound (S), Universal_Real);
21410 Set_Etype (High_Bound (S), Universal_Real);
21411 end Set_Fixed_Range;
21413 ----------------------------------
21414 -- Set_Scalar_Range_For_Subtype --
21415 ----------------------------------
21417 procedure Set_Scalar_Range_For_Subtype
21418 (Def_Id : Entity_Id;
21422 Kind : constant Entity_Kind := Ekind (Def_Id);
21425 -- Defend against previous error
21427 if Nkind (R) = N_Error then
21431 Set_Scalar_Range (Def_Id, R);
21433 -- We need to link the range into the tree before resolving it so
21434 -- that types that are referenced, including importantly the subtype
21435 -- itself, are properly frozen (Freeze_Expression requires that the
21436 -- expression be properly linked into the tree). Of course if it is
21437 -- already linked in, then we do not disturb the current link.
21439 if No (Parent (R)) then
21440 Set_Parent (R, Def_Id);
21443 -- Reset the kind of the subtype during analysis of the range, to
21444 -- catch possible premature use in the bounds themselves.
21446 Set_Ekind (Def_Id, E_Void);
21447 Process_Range_Expr_In_Decl (R, Subt, Subtyp => Def_Id);
21448 Set_Ekind (Def_Id, Kind);
21449 end Set_Scalar_Range_For_Subtype;
21451 --------------------------------------------------------
21452 -- Set_Stored_Constraint_From_Discriminant_Constraint --
21453 --------------------------------------------------------
21455 procedure Set_Stored_Constraint_From_Discriminant_Constraint
21459 -- Make sure set if encountered during Expand_To_Stored_Constraint
21461 Set_Stored_Constraint (E, No_Elist);
21463 -- Give it the right value
21465 if Is_Constrained (E) and then Has_Discriminants (E) then
21466 Set_Stored_Constraint (E,
21467 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
21469 end Set_Stored_Constraint_From_Discriminant_Constraint;
21471 -------------------------------------
21472 -- Signed_Integer_Type_Declaration --
21473 -------------------------------------
21475 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
21476 Implicit_Base : Entity_Id;
21477 Base_Typ : Entity_Id;
21480 Errs : Boolean := False;
21484 function Can_Derive_From (E : Entity_Id) return Boolean;
21485 -- Determine whether given bounds allow derivation from specified type
21487 procedure Check_Bound (Expr : Node_Id);
21488 -- Check bound to make sure it is integral and static. If not, post
21489 -- appropriate error message and set Errs flag
21491 ---------------------
21492 -- Can_Derive_From --
21493 ---------------------
21495 -- Note we check both bounds against both end values, to deal with
21496 -- strange types like ones with a range of 0 .. -12341234.
21498 function Can_Derive_From (E : Entity_Id) return Boolean is
21499 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
21500 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
21502 return Lo <= Lo_Val and then Lo_Val <= Hi
21504 Lo <= Hi_Val and then Hi_Val <= Hi;
21505 end Can_Derive_From;
21511 procedure Check_Bound (Expr : Node_Id) is
21513 -- If a range constraint is used as an integer type definition, each
21514 -- bound of the range must be defined by a static expression of some
21515 -- integer type, but the two bounds need not have the same integer
21516 -- type (Negative bounds are allowed.) (RM 3.5.4)
21518 if not Is_Integer_Type (Etype (Expr)) then
21520 ("integer type definition bounds must be of integer type", Expr);
21523 elsif not Is_OK_Static_Expression (Expr) then
21524 Flag_Non_Static_Expr
21525 ("non-static expression used for integer type bound!", Expr);
21528 -- The bounds are folded into literals, and we set their type to be
21529 -- universal, to avoid typing difficulties: we cannot set the type
21530 -- of the literal to the new type, because this would be a forward
21531 -- reference for the back end, and if the original type is user-
21532 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
21535 if Is_Entity_Name (Expr) then
21536 Fold_Uint (Expr, Expr_Value (Expr), True);
21539 Set_Etype (Expr, Universal_Integer);
21543 -- Start of processing for Signed_Integer_Type_Declaration
21546 -- Create an anonymous base type
21549 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
21551 -- Analyze and check the bounds, they can be of any integer type
21553 Lo := Low_Bound (Def);
21554 Hi := High_Bound (Def);
21556 -- Arbitrarily use Integer as the type if either bound had an error
21558 if Hi = Error or else Lo = Error then
21559 Base_Typ := Any_Integer;
21560 Set_Error_Posted (T, True);
21562 -- Here both bounds are OK expressions
21565 Analyze_And_Resolve (Lo, Any_Integer);
21566 Analyze_And_Resolve (Hi, Any_Integer);
21572 Hi := Type_High_Bound (Standard_Long_Long_Integer);
21573 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
21576 -- Find type to derive from
21578 Lo_Val := Expr_Value (Lo);
21579 Hi_Val := Expr_Value (Hi);
21581 if Can_Derive_From (Standard_Short_Short_Integer) then
21582 Base_Typ := Base_Type (Standard_Short_Short_Integer);
21584 elsif Can_Derive_From (Standard_Short_Integer) then
21585 Base_Typ := Base_Type (Standard_Short_Integer);
21587 elsif Can_Derive_From (Standard_Integer) then
21588 Base_Typ := Base_Type (Standard_Integer);
21590 elsif Can_Derive_From (Standard_Long_Integer) then
21591 Base_Typ := Base_Type (Standard_Long_Integer);
21593 elsif Can_Derive_From (Standard_Long_Long_Integer) then
21594 Check_Restriction (No_Long_Long_Integers, Def);
21595 Base_Typ := Base_Type (Standard_Long_Long_Integer);
21598 Base_Typ := Base_Type (Standard_Long_Long_Integer);
21599 Error_Msg_N ("integer type definition bounds out of range", Def);
21600 Hi := Type_High_Bound (Standard_Long_Long_Integer);
21601 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
21605 -- Complete both implicit base and declared first subtype entities. The
21606 -- inheritance of the rep item chain ensures that SPARK-related pragmas
21607 -- are not clobbered when the signed integer type acts as a full view of
21610 Set_Etype (Implicit_Base, Base_Typ);
21611 Set_Size_Info (Implicit_Base, Base_Typ);
21612 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
21613 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
21614 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
21616 Set_Ekind (T, E_Signed_Integer_Subtype);
21617 Set_Etype (T, Implicit_Base);
21618 Set_Size_Info (T, Implicit_Base);
21619 Inherit_Rep_Item_Chain (T, Implicit_Base);
21620 Set_Scalar_Range (T, Def);
21621 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
21622 Set_Is_Constrained (T);
21623 end Signed_Integer_Type_Declaration;