1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2014, 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 Debug; use Debug;
30 with Elists; use Elists;
31 with Einfo; use Einfo;
32 with Errout; use Errout;
33 with Eval_Fat; use Eval_Fat;
34 with Exp_Ch3; use Exp_Ch3;
35 with Exp_Ch9; use Exp_Ch9;
36 with Exp_Disp; use Exp_Disp;
37 with Exp_Dist; use Exp_Dist;
38 with Exp_Tss; use Exp_Tss;
39 with Exp_Util; use Exp_Util;
40 with Fname; use Fname;
41 with Freeze; use Freeze;
42 with Ghost; use Ghost;
43 with Itypes; use Itypes;
44 with Layout; use Layout;
46 with Lib.Xref; use Lib.Xref;
47 with Namet; use Namet;
48 with Nmake; use Nmake;
50 with Restrict; use Restrict;
51 with Rident; use Rident;
52 with Rtsfind; use Rtsfind;
54 with Sem_Aux; use Sem_Aux;
55 with Sem_Case; use Sem_Case;
56 with Sem_Cat; use Sem_Cat;
57 with Sem_Ch6; use Sem_Ch6;
58 with Sem_Ch7; use Sem_Ch7;
59 with Sem_Ch8; use Sem_Ch8;
60 with Sem_Ch10; use Sem_Ch10;
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_Prag; use Sem_Prag;
69 with Sem_Res; use Sem_Res;
70 with Sem_Smem; use Sem_Smem;
71 with Sem_Type; use Sem_Type;
72 with Sem_Util; use Sem_Util;
73 with Sem_Warn; use Sem_Warn;
74 with Stand; use Stand;
75 with Sinfo; use Sinfo;
76 with Sinput; use Sinput;
77 with Snames; use Snames;
78 with Targparm; use Targparm;
79 with Tbuild; use Tbuild;
80 with Ttypes; use Ttypes;
81 with Uintp; use Uintp;
82 with Urealp; use Urealp;
84 package body Sem_Ch3 is
86 -----------------------
87 -- Local Subprograms --
88 -----------------------
90 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id);
91 -- Ada 2005 (AI-251): Add the tag components corresponding to all the
92 -- abstract interface types implemented by a record type or a derived
95 procedure Analyze_Object_Contract (Obj_Id : Entity_Id);
96 -- Analyze all delayed pragmas chained on the contract of object Obj_Id as
97 -- if they appeared at the end of the declarative region. The pragmas to be
105 procedure Build_Derived_Type
107 Parent_Type : Entity_Id;
108 Derived_Type : Entity_Id;
109 Is_Completion : Boolean;
110 Derive_Subps : Boolean := True);
111 -- Create and decorate a Derived_Type given the Parent_Type entity. N is
112 -- the N_Full_Type_Declaration node containing the derived type definition.
113 -- Parent_Type is the entity for the parent type in the derived type
114 -- definition and Derived_Type the actual derived type. Is_Completion must
115 -- be set to False if Derived_Type is the N_Defining_Identifier node in N
116 -- (i.e. Derived_Type = Defining_Identifier (N)). In this case N is not the
117 -- completion of a private type declaration. If Is_Completion is set to
118 -- True, N is the completion of a private type declaration and Derived_Type
119 -- is different from the defining identifier inside N (i.e. Derived_Type /=
120 -- Defining_Identifier (N)). Derive_Subps indicates whether the parent
121 -- subprograms should be derived. The only case where this parameter is
122 -- False is when Build_Derived_Type is recursively called to process an
123 -- implicit derived full type for a type derived from a private type (in
124 -- that case the subprograms must only be derived for the private view of
127 -- ??? These flags need a bit of re-examination and re-documentation:
128 -- ??? are they both necessary (both seem related to the recursion)?
130 procedure Build_Derived_Access_Type
132 Parent_Type : Entity_Id;
133 Derived_Type : Entity_Id);
134 -- Subsidiary procedure to Build_Derived_Type. For a derived access type,
135 -- create an implicit base if the parent type is constrained or if the
136 -- subtype indication has a constraint.
138 procedure Build_Derived_Array_Type
140 Parent_Type : Entity_Id;
141 Derived_Type : Entity_Id);
142 -- Subsidiary procedure to Build_Derived_Type. For a derived array type,
143 -- create an implicit base if the parent type is constrained or if the
144 -- subtype indication has a constraint.
146 procedure Build_Derived_Concurrent_Type
148 Parent_Type : Entity_Id;
149 Derived_Type : Entity_Id);
150 -- Subsidiary procedure to Build_Derived_Type. For a derived task or
151 -- protected type, inherit entries and protected subprograms, check
152 -- legality of discriminant constraints if any.
154 procedure Build_Derived_Enumeration_Type
156 Parent_Type : Entity_Id;
157 Derived_Type : Entity_Id);
158 -- Subsidiary procedure to Build_Derived_Type. For a derived enumeration
159 -- type, we must create a new list of literals. Types derived from
160 -- Character and [Wide_]Wide_Character are special-cased.
162 procedure Build_Derived_Numeric_Type
164 Parent_Type : Entity_Id;
165 Derived_Type : Entity_Id);
166 -- Subsidiary procedure to Build_Derived_Type. For numeric types, create
167 -- an anonymous base type, and propagate constraint to subtype if needed.
169 procedure Build_Derived_Private_Type
171 Parent_Type : Entity_Id;
172 Derived_Type : Entity_Id;
173 Is_Completion : Boolean;
174 Derive_Subps : Boolean := True);
175 -- Subsidiary procedure to Build_Derived_Type. This procedure is complex
176 -- because the parent may or may not have a completion, and the derivation
177 -- may itself be a completion.
179 procedure Build_Derived_Record_Type
181 Parent_Type : Entity_Id;
182 Derived_Type : Entity_Id;
183 Derive_Subps : Boolean := True);
184 -- Subsidiary procedure used for tagged and untagged record types
185 -- by Build_Derived_Type and Analyze_Private_Extension_Declaration.
186 -- All parameters are as in Build_Derived_Type except that N, in
187 -- addition to being an N_Full_Type_Declaration node, can also be an
188 -- N_Private_Extension_Declaration node. See the definition of this routine
189 -- for much more info. Derive_Subps indicates whether subprograms should be
190 -- derived from the parent type. The only case where Derive_Subps is False
191 -- is for an implicit derived full type for a type derived from a private
192 -- type (see Build_Derived_Type).
194 procedure Build_Discriminal (Discrim : Entity_Id);
195 -- Create the discriminal corresponding to discriminant Discrim, that is
196 -- the parameter corresponding to Discrim to be used in initialization
197 -- procedures for the type where Discrim is a discriminant. Discriminals
198 -- are not used during semantic analysis, and are not fully defined
199 -- entities until expansion. Thus they are not given a scope until
200 -- initialization procedures are built.
202 function Build_Discriminant_Constraints
205 Derived_Def : Boolean := False) return Elist_Id;
206 -- Validate discriminant constraints and return the list of the constraints
207 -- in order of discriminant declarations, where T is the discriminated
208 -- unconstrained type. Def is the N_Subtype_Indication node where the
209 -- discriminants constraints for T are specified. Derived_Def is True
210 -- when building the discriminant constraints in a derived type definition
211 -- of the form "type D (...) is new T (xxx)". In this case T is the parent
212 -- type and Def is the constraint "(xxx)" on T and this routine sets the
213 -- Corresponding_Discriminant field of the discriminants in the derived
214 -- type D to point to the corresponding discriminants in the parent type T.
216 procedure Build_Discriminated_Subtype
220 Related_Nod : Node_Id;
221 For_Access : Boolean := False);
222 -- Subsidiary procedure to Constrain_Discriminated_Type and to
223 -- Process_Incomplete_Dependents. Given
225 -- T (a possibly discriminated base type)
226 -- Def_Id (a very partially built subtype for T),
228 -- the call completes Def_Id to be the appropriate E_*_Subtype.
230 -- The Elist is the list of discriminant constraints if any (it is set
231 -- to No_Elist if T is not a discriminated type, and to an empty list if
232 -- T has discriminants but there are no discriminant constraints). The
233 -- Related_Nod is the same as Decl_Node in Create_Constrained_Components.
234 -- The For_Access says whether or not this subtype is really constraining
235 -- an access type. That is its sole purpose is the designated type of an
236 -- access type -- in which case a Private_Subtype Is_For_Access_Subtype
237 -- is built to avoid freezing T when the access subtype is frozen.
239 function Build_Scalar_Bound
242 Der_T : Entity_Id) return Node_Id;
243 -- The bounds of a derived scalar type are conversions of the bounds of
244 -- the parent type. Optimize the representation if the bounds are literals.
245 -- Needs a more complete spec--what are the parameters exactly, and what
246 -- exactly is the returned value, and how is Bound affected???
248 procedure Build_Underlying_Full_View
252 -- If the completion of a private type is itself derived from a private
253 -- type, or if the full view of a private subtype is itself private, the
254 -- back-end has no way to compute the actual size of this type. We build
255 -- an internal subtype declaration of the proper parent type to convey
256 -- this information. This extra mechanism is needed because a full
257 -- view cannot itself have a full view (it would get clobbered during
260 procedure Check_Access_Discriminant_Requires_Limited
263 -- Check the restriction that the type to which an access discriminant
264 -- belongs must be a concurrent type or a descendant of a type with
265 -- the reserved word 'limited' in its declaration.
267 procedure Check_Anonymous_Access_Components
271 Comp_List : Node_Id);
272 -- Ada 2005 AI-382: an access component in a record definition can refer to
273 -- the enclosing record, in which case it denotes the type itself, and not
274 -- the current instance of the type. We create an anonymous access type for
275 -- the component, and flag it as an access to a component, so accessibility
276 -- checks are properly performed on it. The declaration of the access type
277 -- is placed ahead of that of the record to prevent order-of-elaboration
278 -- circularity issues in Gigi. We create an incomplete type for the record
279 -- declaration, which is the designated type of the anonymous access.
281 procedure Check_Delta_Expression (E : Node_Id);
282 -- Check that the expression represented by E is suitable for use as a
283 -- delta expression, i.e. it is of real type and is static.
285 procedure Check_Digits_Expression (E : Node_Id);
286 -- Check that the expression represented by E is suitable for use as a
287 -- digits expression, i.e. it is of integer type, positive and static.
289 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id);
290 -- Validate the initialization of an object declaration. T is the required
291 -- type, and Exp is the initialization expression.
293 procedure Check_Interfaces (N : Node_Id; Def : Node_Id);
294 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
296 procedure Check_Or_Process_Discriminants
299 Prev : Entity_Id := Empty);
300 -- If N is the full declaration of the completion T of an incomplete or
301 -- private type, check its discriminants (which are already known to be
302 -- conformant with those of the partial view, see Find_Type_Name),
303 -- otherwise process them. Prev is the entity of the partial declaration,
306 procedure Check_Real_Bound (Bound : Node_Id);
307 -- Check given bound for being of real type and static. If not, post an
308 -- appropriate message, and rewrite the bound with the real literal zero.
310 procedure Constant_Redeclaration
314 -- Various checks on legality of full declaration of deferred constant.
315 -- Id is the entity for the redeclaration, N is the N_Object_Declaration,
316 -- node. The caller has not yet set any attributes of this entity.
318 function Contain_Interface
320 Ifaces : Elist_Id) return Boolean;
321 -- Ada 2005: Determine whether Iface is present in the list Ifaces
323 procedure Convert_Scalar_Bounds
325 Parent_Type : Entity_Id;
326 Derived_Type : Entity_Id;
328 -- For derived scalar types, convert the bounds in the type definition to
329 -- the derived type, and complete their analysis. Given a constraint of the
330 -- form ".. new T range Lo .. Hi", Lo and Hi are analyzed and resolved with
331 -- T'Base, the parent_type. The bounds of the derived type (the anonymous
332 -- base) are copies of Lo and Hi. Finally, the bounds of the derived
333 -- subtype are conversions of those bounds to the derived_type, so that
334 -- their typing is consistent.
336 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id);
337 -- Copies attributes from array base type T2 to array base type T1. Copies
338 -- only attributes that apply to base types, but not subtypes.
340 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id);
341 -- Copies attributes from array subtype T2 to array subtype T1. Copies
342 -- attributes that apply to both subtypes and base types.
344 procedure Create_Constrained_Components
348 Constraints : Elist_Id);
349 -- Build the list of entities for a constrained discriminated record
350 -- subtype. If a component depends on a discriminant, replace its subtype
351 -- using the discriminant values in the discriminant constraint. Subt
352 -- is the defining identifier for the subtype whose list of constrained
353 -- entities we will create. Decl_Node is the type declaration node where
354 -- we will attach all the itypes created. Typ is the base discriminated
355 -- type for the subtype Subt. Constraints is the list of discriminant
356 -- constraints for Typ.
358 function Constrain_Component_Type
360 Constrained_Typ : Entity_Id;
361 Related_Node : Node_Id;
363 Constraints : Elist_Id) return Entity_Id;
364 -- Given a discriminated base type Typ, a list of discriminant constraints,
365 -- Constraints, for Typ and a component Comp of Typ, create and return the
366 -- type corresponding to Etype (Comp) where all discriminant references
367 -- are replaced with the corresponding constraint. If Etype (Comp) contains
368 -- no discriminant references then it is returned as-is. Constrained_Typ
369 -- is the final constrained subtype to which the constrained component
370 -- belongs. Related_Node is the node where we attach all created itypes.
372 procedure Constrain_Access
373 (Def_Id : in out Entity_Id;
375 Related_Nod : Node_Id);
376 -- Apply a list of constraints to an access type. If Def_Id is empty, it is
377 -- an anonymous type created for a subtype indication. In that case it is
378 -- created in the procedure and attached to Related_Nod.
380 procedure Constrain_Array
381 (Def_Id : in out Entity_Id;
383 Related_Nod : Node_Id;
384 Related_Id : Entity_Id;
386 -- Apply a list of index constraints to an unconstrained array type. The
387 -- first parameter is the entity for the resulting subtype. A value of
388 -- Empty for Def_Id indicates that an implicit type must be created, but
389 -- creation is delayed (and must be done by this procedure) because other
390 -- subsidiary implicit types must be created first (which is why Def_Id
391 -- is an in/out parameter). The second parameter is a subtype indication
392 -- node for the constrained array to be created (e.g. something of the
393 -- form string (1 .. 10)). Related_Nod gives the place where this type
394 -- has to be inserted in the tree. The Related_Id and Suffix parameters
395 -- are used to build the associated Implicit type name.
397 procedure Constrain_Concurrent
398 (Def_Id : in out Entity_Id;
400 Related_Nod : Node_Id;
401 Related_Id : Entity_Id;
403 -- Apply list of discriminant constraints to an unconstrained concurrent
406 -- SI is the N_Subtype_Indication node containing the constraint and
407 -- the unconstrained type to constrain.
409 -- Def_Id is the entity for the resulting constrained subtype. A value
410 -- of Empty for Def_Id indicates that an implicit type must be created,
411 -- but creation is delayed (and must be done by this procedure) because
412 -- other subsidiary implicit types must be created first (which is why
413 -- Def_Id is an in/out parameter).
415 -- Related_Nod gives the place where this type has to be inserted
418 -- The last two arguments are used to create its external name if needed.
420 function Constrain_Corresponding_Record
421 (Prot_Subt : Entity_Id;
422 Corr_Rec : Entity_Id;
423 Related_Nod : Node_Id) return Entity_Id;
424 -- When constraining a protected type or task type with discriminants,
425 -- constrain the corresponding record with the same discriminant values.
427 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id);
428 -- Constrain a decimal fixed point type with a digits constraint and/or a
429 -- range constraint, and build E_Decimal_Fixed_Point_Subtype entity.
431 procedure Constrain_Discriminated_Type
434 Related_Nod : Node_Id;
435 For_Access : Boolean := False);
436 -- Process discriminant constraints of composite type. Verify that values
437 -- have been provided for all discriminants, that the original type is
438 -- unconstrained, and that the types of the supplied expressions match
439 -- the discriminant types. The first three parameters are like in routine
440 -- Constrain_Concurrent. See Build_Discriminated_Subtype for an explanation
443 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id);
444 -- Constrain an enumeration type with a range constraint. This is identical
445 -- to Constrain_Integer, but for the Ekind of the resulting subtype.
447 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id);
448 -- Constrain a floating point type with either a digits constraint
449 -- and/or a range constraint, building a E_Floating_Point_Subtype.
451 procedure Constrain_Index
454 Related_Nod : Node_Id;
455 Related_Id : Entity_Id;
458 -- Process an index constraint S in a constrained array declaration. The
459 -- constraint can be a subtype name, or a range with or without an explicit
460 -- subtype mark. The index is the corresponding index of the unconstrained
461 -- array. The Related_Id and Suffix parameters are used to build the
462 -- associated Implicit type name.
464 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id);
465 -- Build subtype of a signed or modular integer type
467 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id);
468 -- Constrain an ordinary fixed point type with a range constraint, and
469 -- build an E_Ordinary_Fixed_Point_Subtype entity.
471 procedure Copy_And_Swap (Priv, Full : Entity_Id);
472 -- Copy the Priv entity into the entity of its full declaration then swap
473 -- the two entities in such a manner that the former private type is now
474 -- seen as a full type.
476 procedure Decimal_Fixed_Point_Type_Declaration
479 -- Create a new decimal fixed point type, and apply the constraint to
480 -- obtain a subtype of this new type.
482 procedure Complete_Private_Subtype
485 Full_Base : Entity_Id;
486 Related_Nod : Node_Id);
487 -- Complete the implicit full view of a private subtype by setting the
488 -- appropriate semantic fields. If the full view of the parent is a record
489 -- type, build constrained components of subtype.
491 procedure Derive_Progenitor_Subprograms
492 (Parent_Type : Entity_Id;
493 Tagged_Type : Entity_Id);
494 -- Ada 2005 (AI-251): To complete type derivation, collect the primitive
495 -- operations of progenitors of Tagged_Type, and replace the subsidiary
496 -- subtypes with Tagged_Type, to build the specs of the inherited interface
497 -- primitives. The derived primitives are aliased to those of the
498 -- interface. This routine takes care also of transferring to the full view
499 -- subprograms associated with the partial view of Tagged_Type that cover
500 -- interface primitives.
502 procedure Derived_Standard_Character
504 Parent_Type : Entity_Id;
505 Derived_Type : Entity_Id);
506 -- Subsidiary procedure to Build_Derived_Enumeration_Type which handles
507 -- derivations from types Standard.Character and Standard.Wide_Character.
509 procedure Derived_Type_Declaration
512 Is_Completion : Boolean);
513 -- Process a derived type declaration. Build_Derived_Type is invoked
514 -- to process the actual derived type definition. Parameters N and
515 -- Is_Completion have the same meaning as in Build_Derived_Type.
516 -- T is the N_Defining_Identifier for the entity defined in the
517 -- N_Full_Type_Declaration node N, that is T is the derived type.
519 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id);
520 -- Insert each literal in symbol table, as an overloadable identifier. Each
521 -- enumeration type is mapped into a sequence of integers, and each literal
522 -- is defined as a constant with integer value. If any of the literals are
523 -- character literals, the type is a character type, which means that
524 -- strings are legal aggregates for arrays of components of the type.
526 function Expand_To_Stored_Constraint
528 Constraint : Elist_Id) return Elist_Id;
529 -- Given a constraint (i.e. a list of expressions) on the discriminants of
530 -- Typ, expand it into a constraint on the stored discriminants and return
531 -- the new list of expressions constraining the stored discriminants.
533 function Find_Type_Of_Object
535 Related_Nod : Node_Id) return Entity_Id;
536 -- Get type entity for object referenced by Obj_Def, attaching the implicit
537 -- types generated to Related_Nod.
539 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id);
540 -- Create a new float and apply the constraint to obtain subtype of it
542 function Has_Range_Constraint (N : Node_Id) return Boolean;
543 -- Given an N_Subtype_Indication node N, return True if a range constraint
544 -- is present, either directly, or as part of a digits or delta constraint.
545 -- In addition, a digits constraint in the decimal case returns True, since
546 -- it establishes a default range if no explicit range is present.
548 function Inherit_Components
550 Parent_Base : Entity_Id;
551 Derived_Base : Entity_Id;
553 Inherit_Discr : Boolean;
554 Discs : Elist_Id) return Elist_Id;
555 -- Called from Build_Derived_Record_Type to inherit the components of
556 -- Parent_Base (a base type) into the Derived_Base (the derived base type).
557 -- For more information on derived types and component inheritance please
558 -- consult the comment above the body of Build_Derived_Record_Type.
560 -- N is the original derived type declaration
562 -- Is_Tagged is set if we are dealing with tagged types
564 -- If Inherit_Discr is set, Derived_Base inherits its discriminants from
565 -- Parent_Base, otherwise no discriminants are inherited.
567 -- Discs gives the list of constraints that apply to Parent_Base in the
568 -- derived type declaration. If Discs is set to No_Elist, then we have
569 -- the following situation:
571 -- type Parent (D1..Dn : ..) is [tagged] record ...;
572 -- type Derived is new Parent [with ...];
574 -- which gets treated as
576 -- type Derived (D1..Dn : ..) is new Parent (D1,..,Dn) [with ...];
578 -- For untagged types the returned value is an association list. The list
579 -- starts from the association (Parent_Base => Derived_Base), and then it
580 -- contains a sequence of the associations of the form
582 -- (Old_Component => New_Component),
584 -- where Old_Component is the Entity_Id of a component in Parent_Base and
585 -- New_Component is the Entity_Id of the corresponding component in
586 -- Derived_Base. For untagged records, this association list is needed when
587 -- copying the record declaration for the derived base. In the tagged case
588 -- the value returned is irrelevant.
590 procedure Inherit_Predicate_Flags (Subt, Par : Entity_Id);
591 -- Propagate static and dynamic predicate flags from a parent to the
592 -- subtype in a subtype declaration with and without constraints.
594 function Is_EVF_Procedure (Subp : Entity_Id) return Boolean;
595 -- Subsidiary to Check_Abstract_Overriding and Derive_Subprogram.
596 -- Determine whether subprogram Subp is a procedure subject to pragma
597 -- Extensions_Visible with value False and has at least one controlling
598 -- parameter of mode OUT.
600 function Is_Valid_Constraint_Kind
602 Constraint_Kind : Node_Kind) return Boolean;
603 -- Returns True if it is legal to apply the given kind of constraint to the
604 -- given kind of type (index constraint to an array type, for example).
606 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id);
607 -- Create new modular type. Verify that modulus is in bounds
609 procedure New_Concatenation_Op (Typ : Entity_Id);
610 -- Create an abbreviated declaration for an operator in order to
611 -- materialize concatenation on array types.
613 procedure Ordinary_Fixed_Point_Type_Declaration
616 -- Create a new ordinary fixed point type, and apply the constraint to
617 -- obtain subtype of it.
619 procedure Prepare_Private_Subtype_Completion
621 Related_Nod : Node_Id);
622 -- Id is a subtype of some private type. Creates the full declaration
623 -- associated with Id whenever possible, i.e. when the full declaration
624 -- of the base type is already known. Records each subtype into
625 -- Private_Dependents of the base type.
627 procedure Process_Incomplete_Dependents
631 -- Process all entities that depend on an incomplete type. There include
632 -- subtypes, subprogram types that mention the incomplete type in their
633 -- profiles, and subprogram with access parameters that designate the
636 -- Inc_T is the defining identifier of an incomplete type declaration, its
637 -- Ekind is E_Incomplete_Type.
639 -- N is the corresponding N_Full_Type_Declaration for Inc_T.
641 -- Full_T is N's defining identifier.
643 -- Subtypes of incomplete types with discriminants are completed when the
644 -- parent type is. This is simpler than private subtypes, because they can
645 -- only appear in the same scope, and there is no need to exchange views.
646 -- Similarly, access_to_subprogram types may have a parameter or a return
647 -- type that is an incomplete type, and that must be replaced with the
650 -- If the full type is tagged, subprogram with access parameters that
651 -- designated the incomplete may be primitive operations of the full type,
652 -- and have to be processed accordingly.
654 procedure Process_Real_Range_Specification (Def : Node_Id);
655 -- Given the type definition for a real type, this procedure processes and
656 -- checks the real range specification of this type definition if one is
657 -- present. If errors are found, error messages are posted, and the
658 -- Real_Range_Specification of Def is reset to Empty.
660 procedure Propagate_Default_Init_Cond_Attributes
661 (From_Typ : Entity_Id;
663 Parent_To_Derivation : Boolean := False;
664 Private_To_Full_View : Boolean := False);
665 -- Subsidiary to routines Build_Derived_Type and Process_Full_View. Inherit
666 -- all attributes related to pragma Default_Initial_Condition from From_Typ
667 -- to To_Typ. Flag Parent_To_Derivation should be set when the context is
668 -- the creation of a derived type. Flag Private_To_Full_View should be set
669 -- when processing both views of a private type.
671 procedure Record_Type_Declaration
675 -- Process a record type declaration (for both untagged and tagged
676 -- records). Parameters T and N are exactly like in procedure
677 -- Derived_Type_Declaration, except that no flag Is_Completion is needed
678 -- for this routine. If this is the completion of an incomplete type
679 -- declaration, Prev is the entity of the incomplete declaration, used for
680 -- cross-referencing. Otherwise Prev = T.
682 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id);
683 -- This routine is used to process the actual record type definition (both
684 -- for untagged and tagged records). Def is a record type definition node.
685 -- This procedure analyzes the components in this record type definition.
686 -- Prev_T is the entity for the enclosing record type. It is provided so
687 -- that its Has_Task flag can be set if any of the component have Has_Task
688 -- set. If the declaration is the completion of an incomplete type
689 -- declaration, Prev_T is the original incomplete type, whose full view is
692 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id);
693 -- Subsidiary to Build_Derived_Record_Type. For untagged records, we
694 -- build a copy of the declaration tree of the parent, and we create
695 -- independently the list of components for the derived type. Semantic
696 -- information uses the component entities, but record representation
697 -- clauses are validated on the declaration tree. This procedure replaces
698 -- discriminants and components in the declaration with those that have
699 -- been created by Inherit_Components.
701 procedure Set_Fixed_Range
706 -- Build a range node with the given bounds and set it as the Scalar_Range
707 -- of the given fixed-point type entity. Loc is the source location used
708 -- for the constructed range. See body for further details.
710 procedure Set_Scalar_Range_For_Subtype
714 -- This routine is used to set the scalar range field for a subtype given
715 -- Def_Id, the entity for the subtype, and R, the range expression for the
716 -- scalar range. Subt provides the parent subtype to be used to analyze,
717 -- resolve, and check the given range.
719 procedure Set_Default_SSO (T : Entity_Id);
720 -- T is the entity for an array or record being declared. This procedure
721 -- sets the flags SSO_Set_Low_By_Default/SSO_Set_High_By_Default according
722 -- to the setting of Opt.Default_SSO.
724 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id);
725 -- Create a new signed integer entity, and apply the constraint to obtain
726 -- the required first named subtype of this type.
728 procedure Set_Stored_Constraint_From_Discriminant_Constraint
730 -- E is some record type. This routine computes E's Stored_Constraint
731 -- from its Discriminant_Constraint.
733 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id);
734 -- Check that an entity in a list of progenitors is an interface,
735 -- emit error otherwise.
737 -----------------------
738 -- Access_Definition --
739 -----------------------
741 function Access_Definition
742 (Related_Nod : Node_Id;
743 N : Node_Id) return Entity_Id
745 Anon_Type : Entity_Id;
746 Anon_Scope : Entity_Id;
747 Desig_Type : Entity_Id;
748 Enclosing_Prot_Type : Entity_Id := Empty;
751 Check_SPARK_05_Restriction ("access type is not allowed", N);
753 if Is_Entry (Current_Scope)
754 and then Is_Task_Type (Etype (Scope (Current_Scope)))
756 Error_Msg_N ("task entries cannot have access parameters", N);
760 -- Ada 2005: For an object declaration the corresponding anonymous
761 -- type is declared in the current scope.
763 -- If the access definition is the return type of another access to
764 -- function, scope is the current one, because it is the one of the
765 -- current type declaration, except for the pathological case below.
767 if Nkind_In (Related_Nod, N_Object_Declaration,
768 N_Access_Function_Definition)
770 Anon_Scope := Current_Scope;
772 -- A pathological case: function returning access functions that
773 -- return access functions, etc. Each anonymous access type created
774 -- is in the enclosing scope of the outermost function.
781 while Nkind_In (Par, N_Access_Function_Definition,
787 if Nkind (Par) = N_Function_Specification then
788 Anon_Scope := Scope (Defining_Entity (Par));
792 -- For the anonymous function result case, retrieve the scope of the
793 -- function specification's associated entity rather than using the
794 -- current scope. The current scope will be the function itself if the
795 -- formal part is currently being analyzed, but will be the parent scope
796 -- in the case of a parameterless function, and we always want to use
797 -- the function's parent scope. Finally, if the function is a child
798 -- unit, we must traverse the tree to retrieve the proper entity.
800 elsif Nkind (Related_Nod) = N_Function_Specification
801 and then Nkind (Parent (N)) /= N_Parameter_Specification
803 -- If the current scope is a protected type, the anonymous access
804 -- is associated with one of the protected operations, and must
805 -- be available in the scope that encloses the protected declaration.
806 -- Otherwise the type is in the scope enclosing the subprogram.
808 -- If the function has formals, The return type of a subprogram
809 -- declaration is analyzed in the scope of the subprogram (see
810 -- Process_Formals) and thus the protected type, if present, is
811 -- the scope of the current function scope.
813 if Ekind (Current_Scope) = E_Protected_Type then
814 Enclosing_Prot_Type := Current_Scope;
816 elsif Ekind (Current_Scope) = E_Function
817 and then Ekind (Scope (Current_Scope)) = E_Protected_Type
819 Enclosing_Prot_Type := Scope (Current_Scope);
822 if Present (Enclosing_Prot_Type) then
823 Anon_Scope := Scope (Enclosing_Prot_Type);
826 Anon_Scope := Scope (Defining_Entity (Related_Nod));
829 -- For an access type definition, if the current scope is a child
830 -- unit it is the scope of the type.
832 elsif Is_Compilation_Unit (Current_Scope) then
833 Anon_Scope := Current_Scope;
835 -- For access formals, access components, and access discriminants, the
836 -- scope is that of the enclosing declaration,
839 Anon_Scope := Scope (Current_Scope);
844 (E_Anonymous_Access_Type, Related_Nod, Scope_Id => Anon_Scope);
847 and then Ada_Version >= Ada_2005
849 Error_Msg_N ("ALL is not permitted for anonymous access types", N);
852 -- Ada 2005 (AI-254): In case of anonymous access to subprograms call
853 -- the corresponding semantic routine
855 if Present (Access_To_Subprogram_Definition (N)) then
857 -- Compiler runtime units are compiled in Ada 2005 mode when building
858 -- the runtime library but must also be compilable in Ada 95 mode
859 -- (when bootstrapping the compiler).
861 Check_Compiler_Unit ("anonymous access to subprogram", N);
863 Access_Subprogram_Declaration
864 (T_Name => Anon_Type,
865 T_Def => Access_To_Subprogram_Definition (N));
867 if Ekind (Anon_Type) = E_Access_Protected_Subprogram_Type then
869 (Anon_Type, E_Anonymous_Access_Protected_Subprogram_Type);
871 Set_Ekind (Anon_Type, E_Anonymous_Access_Subprogram_Type);
874 Set_Can_Use_Internal_Rep
875 (Anon_Type, not Always_Compatible_Rep_On_Target);
877 -- If the anonymous access is associated with a protected operation,
878 -- create a reference to it after the enclosing protected definition
879 -- because the itype will be used in the subsequent bodies.
881 if Ekind (Current_Scope) = E_Protected_Type then
882 Build_Itype_Reference (Anon_Type, Parent (Current_Scope));
888 Find_Type (Subtype_Mark (N));
889 Desig_Type := Entity (Subtype_Mark (N));
891 Set_Directly_Designated_Type (Anon_Type, Desig_Type);
892 Set_Etype (Anon_Type, Anon_Type);
894 -- Make sure the anonymous access type has size and alignment fields
895 -- set, as required by gigi. This is necessary in the case of the
896 -- Task_Body_Procedure.
898 if not Has_Private_Component (Desig_Type) then
899 Layout_Type (Anon_Type);
902 -- Ada 2005 (AI-231): Ada 2005 semantics for anonymous access differs
903 -- from Ada 95 semantics. In Ada 2005, anonymous access must specify if
904 -- the null value is allowed. In Ada 95 the null value is never allowed.
906 if Ada_Version >= Ada_2005 then
907 Set_Can_Never_Be_Null (Anon_Type, Null_Exclusion_Present (N));
909 Set_Can_Never_Be_Null (Anon_Type, True);
912 -- The anonymous access type is as public as the discriminated type or
913 -- subprogram that defines it. It is imported (for back-end purposes)
914 -- if the designated type is.
916 Set_Is_Public (Anon_Type, Is_Public (Scope (Anon_Type)));
918 -- Ada 2005 (AI-231): Propagate the access-constant attribute
920 Set_Is_Access_Constant (Anon_Type, Constant_Present (N));
922 -- The context is either a subprogram declaration, object declaration,
923 -- or an access discriminant, in a private or a full type declaration.
924 -- In the case of a subprogram, if the designated type is incomplete,
925 -- the operation will be a primitive operation of the full type, to be
926 -- updated subsequently. If the type is imported through a limited_with
927 -- clause, the subprogram is not a primitive operation of the type
928 -- (which is declared elsewhere in some other scope).
930 if Ekind (Desig_Type) = E_Incomplete_Type
931 and then not From_Limited_With (Desig_Type)
932 and then Is_Overloadable (Current_Scope)
934 Append_Elmt (Current_Scope, Private_Dependents (Desig_Type));
935 Set_Has_Delayed_Freeze (Current_Scope);
938 -- Ada 2005: If the designated type is an interface that may contain
939 -- tasks, create a Master entity for the declaration. This must be done
940 -- before expansion of the full declaration, because the declaration may
941 -- include an expression that is an allocator, whose expansion needs the
942 -- proper Master for the created tasks.
944 if Nkind (Related_Nod) = N_Object_Declaration and then Expander_Active
946 if Is_Interface (Desig_Type) and then Is_Limited_Record (Desig_Type)
948 Build_Class_Wide_Master (Anon_Type);
950 -- Similarly, if the type is an anonymous access that designates
951 -- tasks, create a master entity for it in the current context.
953 elsif Has_Task (Desig_Type) and then Comes_From_Source (Related_Nod)
955 Build_Master_Entity (Defining_Identifier (Related_Nod));
956 Build_Master_Renaming (Anon_Type);
960 -- For a private component of a protected type, it is imperative that
961 -- the back-end elaborate the type immediately after the protected
962 -- declaration, because this type will be used in the declarations
963 -- created for the component within each protected body, so we must
964 -- create an itype reference for it now.
966 if Nkind (Parent (Related_Nod)) = N_Protected_Definition then
967 Build_Itype_Reference (Anon_Type, Parent (Parent (Related_Nod)));
969 -- Similarly, if the access definition is the return result of a
970 -- function, create an itype reference for it because it will be used
971 -- within the function body. For a regular function that is not a
972 -- compilation unit, insert reference after the declaration. For a
973 -- protected operation, insert it after the enclosing protected type
974 -- declaration. In either case, do not create a reference for a type
975 -- obtained through a limited_with clause, because this would introduce
976 -- semantic dependencies.
978 -- Similarly, do not create a reference if the designated type is a
979 -- generic formal, because no use of it will reach the backend.
981 elsif Nkind (Related_Nod) = N_Function_Specification
982 and then not From_Limited_With (Desig_Type)
983 and then not Is_Generic_Type (Desig_Type)
985 if Present (Enclosing_Prot_Type) then
986 Build_Itype_Reference (Anon_Type, Parent (Enclosing_Prot_Type));
988 elsif Is_List_Member (Parent (Related_Nod))
989 and then Nkind (Parent (N)) /= N_Parameter_Specification
991 Build_Itype_Reference (Anon_Type, Parent (Related_Nod));
994 -- Finally, create an itype reference for an object declaration of an
995 -- anonymous access type. This is strictly necessary only for deferred
996 -- constants, but in any case will avoid out-of-scope problems in the
999 elsif Nkind (Related_Nod) = N_Object_Declaration then
1000 Build_Itype_Reference (Anon_Type, Related_Nod);
1004 end Access_Definition;
1006 -----------------------------------
1007 -- Access_Subprogram_Declaration --
1008 -----------------------------------
1010 procedure Access_Subprogram_Declaration
1011 (T_Name : Entity_Id;
1014 procedure Check_For_Premature_Usage (Def : Node_Id);
1015 -- Check that type T_Name is not used, directly or recursively, as a
1016 -- parameter or a return type in Def. Def is either a subtype, an
1017 -- access_definition, or an access_to_subprogram_definition.
1019 -------------------------------
1020 -- Check_For_Premature_Usage --
1021 -------------------------------
1023 procedure Check_For_Premature_Usage (Def : Node_Id) is
1027 -- Check for a subtype mark
1029 if Nkind (Def) in N_Has_Etype then
1030 if Etype (Def) = T_Name then
1032 ("type& cannot be used before end of its declaration", Def);
1035 -- If this is not a subtype, then this is an access_definition
1037 elsif Nkind (Def) = N_Access_Definition then
1038 if Present (Access_To_Subprogram_Definition (Def)) then
1039 Check_For_Premature_Usage
1040 (Access_To_Subprogram_Definition (Def));
1042 Check_For_Premature_Usage (Subtype_Mark (Def));
1045 -- The only cases left are N_Access_Function_Definition and
1046 -- N_Access_Procedure_Definition.
1049 if Present (Parameter_Specifications (Def)) then
1050 Param := First (Parameter_Specifications (Def));
1051 while Present (Param) loop
1052 Check_For_Premature_Usage (Parameter_Type (Param));
1053 Param := Next (Param);
1057 if Nkind (Def) = N_Access_Function_Definition then
1058 Check_For_Premature_Usage (Result_Definition (Def));
1061 end Check_For_Premature_Usage;
1065 Formals : constant List_Id := Parameter_Specifications (T_Def);
1068 Desig_Type : constant Entity_Id :=
1069 Create_Itype (E_Subprogram_Type, Parent (T_Def));
1071 -- Start of processing for Access_Subprogram_Declaration
1074 Check_SPARK_05_Restriction ("access type is not allowed", T_Def);
1076 -- Associate the Itype node with the inner full-type declaration or
1077 -- subprogram spec or entry body. This is required to handle nested
1078 -- anonymous declarations. For example:
1081 -- (X : access procedure
1082 -- (Y : access procedure
1085 D_Ityp := Associated_Node_For_Itype (Desig_Type);
1086 while not (Nkind_In (D_Ityp, N_Full_Type_Declaration,
1087 N_Private_Type_Declaration,
1088 N_Private_Extension_Declaration,
1089 N_Procedure_Specification,
1090 N_Function_Specification,
1094 Nkind_In (D_Ityp, N_Object_Declaration,
1095 N_Object_Renaming_Declaration,
1096 N_Formal_Object_Declaration,
1097 N_Formal_Type_Declaration,
1098 N_Task_Type_Declaration,
1099 N_Protected_Type_Declaration))
1101 D_Ityp := Parent (D_Ityp);
1102 pragma Assert (D_Ityp /= Empty);
1105 Set_Associated_Node_For_Itype (Desig_Type, D_Ityp);
1107 if Nkind_In (D_Ityp, N_Procedure_Specification,
1108 N_Function_Specification)
1110 Set_Scope (Desig_Type, Scope (Defining_Entity (D_Ityp)));
1112 elsif Nkind_In (D_Ityp, N_Full_Type_Declaration,
1113 N_Object_Declaration,
1114 N_Object_Renaming_Declaration,
1115 N_Formal_Type_Declaration)
1117 Set_Scope (Desig_Type, Scope (Defining_Identifier (D_Ityp)));
1120 if Nkind (T_Def) = N_Access_Function_Definition then
1121 if Nkind (Result_Definition (T_Def)) = N_Access_Definition then
1123 Acc : constant Node_Id := Result_Definition (T_Def);
1126 if Present (Access_To_Subprogram_Definition (Acc))
1128 Protected_Present (Access_To_Subprogram_Definition (Acc))
1132 Replace_Anonymous_Access_To_Protected_Subprogram
1138 Access_Definition (T_Def, Result_Definition (T_Def)));
1143 Analyze (Result_Definition (T_Def));
1146 Typ : constant Entity_Id := Entity (Result_Definition (T_Def));
1149 -- If a null exclusion is imposed on the result type, then
1150 -- create a null-excluding itype (an access subtype) and use
1151 -- it as the function's Etype.
1153 if Is_Access_Type (Typ)
1154 and then Null_Exclusion_In_Return_Present (T_Def)
1156 Set_Etype (Desig_Type,
1157 Create_Null_Excluding_Itype
1159 Related_Nod => T_Def,
1160 Scope_Id => Current_Scope));
1163 if From_Limited_With (Typ) then
1165 -- AI05-151: Incomplete types are allowed in all basic
1166 -- declarations, including access to subprograms.
1168 if Ada_Version >= Ada_2012 then
1173 ("illegal use of incomplete type&",
1174 Result_Definition (T_Def), Typ);
1177 elsif Ekind (Current_Scope) = E_Package
1178 and then In_Private_Part (Current_Scope)
1180 if Ekind (Typ) = E_Incomplete_Type then
1181 Append_Elmt (Desig_Type, Private_Dependents (Typ));
1183 elsif Is_Class_Wide_Type (Typ)
1184 and then Ekind (Etype (Typ)) = E_Incomplete_Type
1187 (Desig_Type, Private_Dependents (Etype (Typ)));
1191 Set_Etype (Desig_Type, Typ);
1196 if not (Is_Type (Etype (Desig_Type))) then
1198 ("expect type in function specification",
1199 Result_Definition (T_Def));
1203 Set_Etype (Desig_Type, Standard_Void_Type);
1206 if Present (Formals) then
1207 Push_Scope (Desig_Type);
1209 -- Some special tests here. These special tests can be removed
1210 -- if and when Itypes always have proper parent pointers to their
1213 -- Special test 1) Link defining_identifier of formals. Required by
1214 -- First_Formal to provide its functionality.
1220 F := First (Formals);
1222 -- In ASIS mode, the access_to_subprogram may be analyzed twice,
1223 -- when it is part of an unconstrained type and subtype expansion
1224 -- is disabled. To avoid back-end problems with shared profiles,
1225 -- use previous subprogram type as the designated type, and then
1226 -- remove scope added above.
1228 if ASIS_Mode and then Present (Scope (Defining_Identifier (F)))
1230 Set_Etype (T_Name, T_Name);
1231 Init_Size_Align (T_Name);
1232 Set_Directly_Designated_Type (T_Name,
1233 Scope (Defining_Identifier (F)));
1238 while Present (F) loop
1239 if No (Parent (Defining_Identifier (F))) then
1240 Set_Parent (Defining_Identifier (F), F);
1247 Process_Formals (Formals, Parent (T_Def));
1249 -- Special test 2) End_Scope requires that the parent pointer be set
1250 -- to something reasonable, but Itypes don't have parent pointers. So
1251 -- we set it and then unset it ???
1253 Set_Parent (Desig_Type, T_Name);
1255 Set_Parent (Desig_Type, Empty);
1258 -- Check for premature usage of the type being defined
1260 Check_For_Premature_Usage (T_Def);
1262 -- The return type and/or any parameter type may be incomplete. Mark the
1263 -- subprogram_type as depending on the incomplete type, so that it can
1264 -- be updated when the full type declaration is seen. This only applies
1265 -- to incomplete types declared in some enclosing scope, not to limited
1266 -- views from other packages.
1268 -- Prior to Ada 2012, access to functions can only have in_parameters.
1270 if Present (Formals) then
1271 Formal := First_Formal (Desig_Type);
1272 while Present (Formal) loop
1273 if Ekind (Formal) /= E_In_Parameter
1274 and then Nkind (T_Def) = N_Access_Function_Definition
1275 and then Ada_Version < Ada_2012
1277 Error_Msg_N ("functions can only have IN parameters", Formal);
1280 if Ekind (Etype (Formal)) = E_Incomplete_Type
1281 and then In_Open_Scopes (Scope (Etype (Formal)))
1283 Append_Elmt (Desig_Type, Private_Dependents (Etype (Formal)));
1284 Set_Has_Delayed_Freeze (Desig_Type);
1287 Next_Formal (Formal);
1291 -- Check whether an indirect call without actuals may be possible. This
1292 -- is used when resolving calls whose result is then indexed.
1294 May_Need_Actuals (Desig_Type);
1296 -- If the return type is incomplete, this is legal as long as the type
1297 -- is declared in the current scope and will be completed in it (rather
1298 -- than being part of limited view).
1300 if Ekind (Etype (Desig_Type)) = E_Incomplete_Type
1301 and then not Has_Delayed_Freeze (Desig_Type)
1302 and then In_Open_Scopes (Scope (Etype (Desig_Type)))
1304 Append_Elmt (Desig_Type, Private_Dependents (Etype (Desig_Type)));
1305 Set_Has_Delayed_Freeze (Desig_Type);
1308 Check_Delayed_Subprogram (Desig_Type);
1310 if Protected_Present (T_Def) then
1311 Set_Ekind (T_Name, E_Access_Protected_Subprogram_Type);
1312 Set_Convention (Desig_Type, Convention_Protected);
1314 Set_Ekind (T_Name, E_Access_Subprogram_Type);
1317 Set_Can_Use_Internal_Rep (T_Name, not Always_Compatible_Rep_On_Target);
1319 Set_Etype (T_Name, T_Name);
1320 Init_Size_Align (T_Name);
1321 Set_Directly_Designated_Type (T_Name, Desig_Type);
1323 Generate_Reference_To_Formals (T_Name);
1325 -- Ada 2005 (AI-231): Propagate the null-excluding attribute
1327 Set_Can_Never_Be_Null (T_Name, Null_Exclusion_Present (T_Def));
1329 Check_Restriction (No_Access_Subprograms, T_Def);
1330 end Access_Subprogram_Declaration;
1332 ----------------------------
1333 -- Access_Type_Declaration --
1334 ----------------------------
1336 procedure Access_Type_Declaration (T : Entity_Id; Def : Node_Id) is
1337 P : constant Node_Id := Parent (Def);
1338 S : constant Node_Id := Subtype_Indication (Def);
1340 Full_Desig : Entity_Id;
1343 Check_SPARK_05_Restriction ("access type is not allowed", Def);
1345 -- Check for permissible use of incomplete type
1347 if Nkind (S) /= N_Subtype_Indication then
1350 if Ekind (Root_Type (Entity (S))) = E_Incomplete_Type then
1351 Set_Directly_Designated_Type (T, Entity (S));
1353 -- If the designated type is a limited view, we cannot tell if
1354 -- the full view contains tasks, and there is no way to handle
1355 -- that full view in a client. We create a master entity for the
1356 -- scope, which will be used when a client determines that one
1359 if From_Limited_With (Entity (S))
1360 and then not Is_Class_Wide_Type (Entity (S))
1362 Set_Ekind (T, E_Access_Type);
1363 Build_Master_Entity (T);
1364 Build_Master_Renaming (T);
1368 Set_Directly_Designated_Type (T, Process_Subtype (S, P, T, 'P'));
1371 -- If the access definition is of the form: ACCESS NOT NULL ..
1372 -- the subtype indication must be of an access type. Create
1373 -- a null-excluding subtype of it.
1375 if Null_Excluding_Subtype (Def) then
1376 if not Is_Access_Type (Entity (S)) then
1377 Error_Msg_N ("null exclusion must apply to access type", Def);
1381 Loc : constant Source_Ptr := Sloc (S);
1383 Nam : constant Entity_Id := Make_Temporary (Loc, 'S');
1387 Make_Subtype_Declaration (Loc,
1388 Defining_Identifier => Nam,
1389 Subtype_Indication =>
1390 New_Occurrence_Of (Entity (S), Loc));
1391 Set_Null_Exclusion_Present (Decl);
1392 Insert_Before (Parent (Def), Decl);
1394 Set_Entity (S, Nam);
1400 Set_Directly_Designated_Type (T,
1401 Process_Subtype (S, P, T, 'P'));
1404 if All_Present (Def) or Constant_Present (Def) then
1405 Set_Ekind (T, E_General_Access_Type);
1407 Set_Ekind (T, E_Access_Type);
1410 Full_Desig := Designated_Type (T);
1412 if Base_Type (Full_Desig) = T then
1413 Error_Msg_N ("access type cannot designate itself", S);
1415 -- In Ada 2005, the type may have a limited view through some unit in
1416 -- its own context, allowing the following circularity that cannot be
1417 -- detected earlier.
1419 elsif Is_Class_Wide_Type (Full_Desig) and then Etype (Full_Desig) = T
1422 ("access type cannot designate its own classwide type", S);
1424 -- Clean up indication of tagged status to prevent cascaded errors
1426 Set_Is_Tagged_Type (T, False);
1431 -- If the type has appeared already in a with_type clause, it is frozen
1432 -- and the pointer size is already set. Else, initialize.
1434 if not From_Limited_With (T) then
1435 Init_Size_Align (T);
1438 -- Note that Has_Task is always false, since the access type itself
1439 -- is not a task type. See Einfo for more description on this point.
1440 -- Exactly the same consideration applies to Has_Controlled_Component
1441 -- and to Has_Protected.
1443 Set_Has_Task (T, False);
1444 Set_Has_Controlled_Component (T, False);
1445 Set_Has_Protected (T, False);
1447 -- Initialize field Finalization_Master explicitly to Empty, to avoid
1448 -- problems where an incomplete view of this entity has been previously
1449 -- established by a limited with and an overlaid version of this field
1450 -- (Stored_Constraint) was initialized for the incomplete view.
1452 -- This reset is performed in most cases except where the access type
1453 -- has been created for the purposes of allocating or deallocating a
1454 -- build-in-place object. Such access types have explicitly set pools
1455 -- and finalization masters.
1457 if No (Associated_Storage_Pool (T)) then
1458 Set_Finalization_Master (T, Empty);
1461 -- Ada 2005 (AI-231): Propagate the null-excluding and access-constant
1464 Set_Can_Never_Be_Null (T, Null_Exclusion_Present (Def));
1465 Set_Is_Access_Constant (T, Constant_Present (Def));
1466 end Access_Type_Declaration;
1468 ----------------------------------
1469 -- Add_Interface_Tag_Components --
1470 ----------------------------------
1472 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id) is
1473 Loc : constant Source_Ptr := Sloc (N);
1477 procedure Add_Tag (Iface : Entity_Id);
1478 -- Add tag for one of the progenitor interfaces
1484 procedure Add_Tag (Iface : Entity_Id) is
1491 pragma Assert (Is_Tagged_Type (Iface) and then Is_Interface (Iface));
1493 -- This is a reasonable place to propagate predicates
1495 if Has_Predicates (Iface) then
1496 Set_Has_Predicates (Typ);
1500 Make_Component_Definition (Loc,
1501 Aliased_Present => True,
1502 Subtype_Indication =>
1503 New_Occurrence_Of (RTE (RE_Interface_Tag), Loc));
1505 Tag := Make_Temporary (Loc, 'V');
1508 Make_Component_Declaration (Loc,
1509 Defining_Identifier => Tag,
1510 Component_Definition => Def);
1512 Analyze_Component_Declaration (Decl);
1514 Set_Analyzed (Decl);
1515 Set_Ekind (Tag, E_Component);
1517 Set_Is_Aliased (Tag);
1518 Set_Related_Type (Tag, Iface);
1519 Init_Component_Location (Tag);
1521 pragma Assert (Is_Frozen (Iface));
1523 Set_DT_Entry_Count (Tag,
1524 DT_Entry_Count (First_Entity (Iface)));
1526 if No (Last_Tag) then
1529 Insert_After (Last_Tag, Decl);
1534 -- If the ancestor has discriminants we need to give special support
1535 -- to store the offset_to_top value of the secondary dispatch tables.
1536 -- For this purpose we add a supplementary component just after the
1537 -- field that contains the tag associated with each secondary DT.
1539 if Typ /= Etype (Typ) and then Has_Discriminants (Etype (Typ)) then
1541 Make_Component_Definition (Loc,
1542 Subtype_Indication =>
1543 New_Occurrence_Of (RTE (RE_Storage_Offset), Loc));
1545 Offset := Make_Temporary (Loc, 'V');
1548 Make_Component_Declaration (Loc,
1549 Defining_Identifier => Offset,
1550 Component_Definition => Def);
1552 Analyze_Component_Declaration (Decl);
1554 Set_Analyzed (Decl);
1555 Set_Ekind (Offset, E_Component);
1556 Set_Is_Aliased (Offset);
1557 Set_Related_Type (Offset, Iface);
1558 Init_Component_Location (Offset);
1559 Insert_After (Last_Tag, Decl);
1570 -- Start of processing for Add_Interface_Tag_Components
1573 if not RTE_Available (RE_Interface_Tag) then
1575 ("(Ada 2005) interface types not supported by this run-time!",
1580 if Ekind (Typ) /= E_Record_Type
1581 or else (Is_Concurrent_Record_Type (Typ)
1582 and then Is_Empty_List (Abstract_Interface_List (Typ)))
1583 or else (not Is_Concurrent_Record_Type (Typ)
1584 and then No (Interfaces (Typ))
1585 and then Is_Empty_Elmt_List (Interfaces (Typ)))
1590 -- Find the current last tag
1592 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1593 Ext := Record_Extension_Part (Type_Definition (N));
1595 pragma Assert (Nkind (Type_Definition (N)) = N_Record_Definition);
1596 Ext := Type_Definition (N);
1601 if not (Present (Component_List (Ext))) then
1602 Set_Null_Present (Ext, False);
1604 Set_Component_List (Ext,
1605 Make_Component_List (Loc,
1606 Component_Items => L,
1607 Null_Present => False));
1609 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1610 L := Component_Items
1612 (Record_Extension_Part
1613 (Type_Definition (N))));
1615 L := Component_Items
1617 (Type_Definition (N)));
1620 -- Find the last tag component
1623 while Present (Comp) loop
1624 if Nkind (Comp) = N_Component_Declaration
1625 and then Is_Tag (Defining_Identifier (Comp))
1634 -- At this point L references the list of components and Last_Tag
1635 -- references the current last tag (if any). Now we add the tag
1636 -- corresponding with all the interfaces that are not implemented
1639 if Present (Interfaces (Typ)) then
1640 Elmt := First_Elmt (Interfaces (Typ));
1641 while Present (Elmt) loop
1642 Add_Tag (Node (Elmt));
1646 end Add_Interface_Tag_Components;
1648 -------------------------------------
1649 -- Add_Internal_Interface_Entities --
1650 -------------------------------------
1652 procedure Add_Internal_Interface_Entities (Tagged_Type : Entity_Id) is
1655 Iface_Elmt : Elmt_Id;
1656 Iface_Prim : Entity_Id;
1657 Ifaces_List : Elist_Id;
1658 New_Subp : Entity_Id := Empty;
1660 Restore_Scope : Boolean := False;
1663 pragma Assert (Ada_Version >= Ada_2005
1664 and then Is_Record_Type (Tagged_Type)
1665 and then Is_Tagged_Type (Tagged_Type)
1666 and then Has_Interfaces (Tagged_Type)
1667 and then not Is_Interface (Tagged_Type));
1669 -- Ensure that the internal entities are added to the scope of the type
1671 if Scope (Tagged_Type) /= Current_Scope then
1672 Push_Scope (Scope (Tagged_Type));
1673 Restore_Scope := True;
1676 Collect_Interfaces (Tagged_Type, Ifaces_List);
1678 Iface_Elmt := First_Elmt (Ifaces_List);
1679 while Present (Iface_Elmt) loop
1680 Iface := Node (Iface_Elmt);
1682 -- Originally we excluded here from this processing interfaces that
1683 -- are parents of Tagged_Type because their primitives are located
1684 -- in the primary dispatch table (and hence no auxiliary internal
1685 -- entities are required to handle secondary dispatch tables in such
1686 -- case). However, these auxiliary entities are also required to
1687 -- handle derivations of interfaces in formals of generics (see
1688 -- Derive_Subprograms).
1690 Elmt := First_Elmt (Primitive_Operations (Iface));
1691 while Present (Elmt) loop
1692 Iface_Prim := Node (Elmt);
1694 if not Is_Predefined_Dispatching_Operation (Iface_Prim) then
1696 Find_Primitive_Covering_Interface
1697 (Tagged_Type => Tagged_Type,
1698 Iface_Prim => Iface_Prim);
1700 if No (Prim) and then Serious_Errors_Detected > 0 then
1704 pragma Assert (Present (Prim));
1706 -- Ada 2012 (AI05-0197): If the name of the covering primitive
1707 -- differs from the name of the interface primitive then it is
1708 -- a private primitive inherited from a parent type. In such
1709 -- case, given that Tagged_Type covers the interface, the
1710 -- inherited private primitive becomes visible. For such
1711 -- purpose we add a new entity that renames the inherited
1712 -- private primitive.
1714 if Chars (Prim) /= Chars (Iface_Prim) then
1715 pragma Assert (Has_Suffix (Prim, 'P'));
1717 (New_Subp => New_Subp,
1718 Parent_Subp => Iface_Prim,
1719 Derived_Type => Tagged_Type,
1720 Parent_Type => Iface);
1721 Set_Alias (New_Subp, Prim);
1722 Set_Is_Abstract_Subprogram
1723 (New_Subp, Is_Abstract_Subprogram (Prim));
1727 (New_Subp => New_Subp,
1728 Parent_Subp => Iface_Prim,
1729 Derived_Type => Tagged_Type,
1730 Parent_Type => Iface);
1732 -- Ada 2005 (AI-251): Decorate internal entity Iface_Subp
1733 -- associated with interface types. These entities are
1734 -- only registered in the list of primitives of its
1735 -- corresponding tagged type because they are only used
1736 -- to fill the contents of the secondary dispatch tables.
1737 -- Therefore they are removed from the homonym chains.
1739 Set_Is_Hidden (New_Subp);
1740 Set_Is_Internal (New_Subp);
1741 Set_Alias (New_Subp, Prim);
1742 Set_Is_Abstract_Subprogram
1743 (New_Subp, Is_Abstract_Subprogram (Prim));
1744 Set_Interface_Alias (New_Subp, Iface_Prim);
1746 -- If the returned type is an interface then propagate it to
1747 -- the returned type. Needed by the thunk to generate the code
1748 -- which displaces "this" to reference the corresponding
1749 -- secondary dispatch table in the returned object.
1751 if Is_Interface (Etype (Iface_Prim)) then
1752 Set_Etype (New_Subp, Etype (Iface_Prim));
1755 -- Internal entities associated with interface types are
1756 -- only registered in the list of primitives of the tagged
1757 -- type. They are only used to fill the contents of the
1758 -- secondary dispatch tables. Therefore they are not needed
1759 -- in the homonym chains.
1761 Remove_Homonym (New_Subp);
1763 -- Hidden entities associated with interfaces must have set
1764 -- the Has_Delay_Freeze attribute to ensure that, in case of
1765 -- locally defined tagged types (or compiling with static
1766 -- dispatch tables generation disabled) the corresponding
1767 -- entry of the secondary dispatch table is filled when
1768 -- such an entity is frozen.
1770 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 Id : constant Entity_Id := Defining_Identifier (N);
1791 E : constant Node_Id := Expression (N);
1792 Typ : constant Node_Id :=
1793 Subtype_Indication (Component_Definition (N));
1797 function Contains_POC (Constr : Node_Id) return Boolean;
1798 -- Determines whether a constraint uses the discriminant of a record
1799 -- type thus becoming a per-object constraint (POC).
1801 function Is_Known_Limited (Typ : Entity_Id) return Boolean;
1802 -- Typ is the type of the current component, check whether this type is
1803 -- a limited type. Used to validate declaration against that of
1804 -- enclosing record.
1810 function Contains_POC (Constr : Node_Id) return Boolean is
1812 -- Prevent cascaded errors
1814 if Error_Posted (Constr) then
1818 case Nkind (Constr) is
1819 when N_Attribute_Reference =>
1820 return Attribute_Name (Constr) = Name_Access
1821 and then Prefix (Constr) = Scope (Entity (Prefix (Constr)));
1823 when N_Discriminant_Association =>
1824 return Denotes_Discriminant (Expression (Constr));
1826 when N_Identifier =>
1827 return Denotes_Discriminant (Constr);
1829 when N_Index_Or_Discriminant_Constraint =>
1834 IDC := First (Constraints (Constr));
1835 while Present (IDC) loop
1837 -- One per-object constraint is sufficient
1839 if Contains_POC (IDC) then
1850 return Denotes_Discriminant (Low_Bound (Constr))
1852 Denotes_Discriminant (High_Bound (Constr));
1854 when N_Range_Constraint =>
1855 return Denotes_Discriminant (Range_Expression (Constr));
1863 ----------------------
1864 -- Is_Known_Limited --
1865 ----------------------
1867 function Is_Known_Limited (Typ : Entity_Id) return Boolean is
1868 P : constant Entity_Id := Etype (Typ);
1869 R : constant Entity_Id := Root_Type (Typ);
1872 if Is_Limited_Record (Typ) then
1875 -- If the root type is limited (and not a limited interface)
1876 -- so is the current type
1878 elsif Is_Limited_Record (R)
1879 and then (not Is_Interface (R) or else not Is_Limited_Interface (R))
1883 -- Else the type may have a limited interface progenitor, but a
1884 -- limited record parent.
1886 elsif R /= P and then Is_Limited_Record (P) then
1892 end Is_Known_Limited;
1894 -- Start of processing for Analyze_Component_Declaration
1897 Generate_Definition (Id);
1900 if Present (Typ) then
1901 T := Find_Type_Of_Object
1902 (Subtype_Indication (Component_Definition (N)), N);
1904 if not Nkind_In (Typ, N_Identifier, N_Expanded_Name) then
1905 Check_SPARK_05_Restriction ("subtype mark required", Typ);
1908 -- Ada 2005 (AI-230): Access Definition case
1911 pragma Assert (Present
1912 (Access_Definition (Component_Definition (N))));
1914 T := Access_Definition
1916 N => Access_Definition (Component_Definition (N)));
1917 Set_Is_Local_Anonymous_Access (T);
1919 -- Ada 2005 (AI-254)
1921 if Present (Access_To_Subprogram_Definition
1922 (Access_Definition (Component_Definition (N))))
1923 and then Protected_Present (Access_To_Subprogram_Definition
1925 (Component_Definition (N))))
1927 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1931 -- If the subtype is a constrained subtype of the enclosing record,
1932 -- (which must have a partial view) the back-end does not properly
1933 -- handle the recursion. Rewrite the component declaration with an
1934 -- explicit subtype indication, which is acceptable to Gigi. We can copy
1935 -- the tree directly because side effects have already been removed from
1936 -- discriminant constraints.
1938 if Ekind (T) = E_Access_Subtype
1939 and then Is_Entity_Name (Subtype_Indication (Component_Definition (N)))
1940 and then Comes_From_Source (T)
1941 and then Nkind (Parent (T)) = N_Subtype_Declaration
1942 and then Etype (Directly_Designated_Type (T)) = Current_Scope
1945 (Subtype_Indication (Component_Definition (N)),
1946 New_Copy_Tree (Subtype_Indication (Parent (T))));
1947 T := Find_Type_Of_Object
1948 (Subtype_Indication (Component_Definition (N)), N);
1951 -- If the component declaration includes a default expression, then we
1952 -- check that the component is not of a limited type (RM 3.7(5)),
1953 -- and do the special preanalysis of the expression (see section on
1954 -- "Handling of Default and Per-Object Expressions" in the spec of
1958 Check_SPARK_05_Restriction ("default expression is not allowed", E);
1959 Preanalyze_Default_Expression (E, T);
1960 Check_Initialization (T, E);
1962 if Ada_Version >= Ada_2005
1963 and then Ekind (T) = E_Anonymous_Access_Type
1964 and then Etype (E) /= Any_Type
1966 -- Check RM 3.9.2(9): "if the expected type for an expression is
1967 -- an anonymous access-to-specific tagged type, then the object
1968 -- designated by the expression shall not be dynamically tagged
1969 -- unless it is a controlling operand in a call on a dispatching
1972 if Is_Tagged_Type (Directly_Designated_Type (T))
1974 Ekind (Directly_Designated_Type (T)) /= E_Class_Wide_Type
1976 Ekind (Directly_Designated_Type (Etype (E))) =
1980 ("access to specific tagged type required (RM 3.9.2(9))", E);
1983 -- (Ada 2005: AI-230): Accessibility check for anonymous
1986 if Type_Access_Level (Etype (E)) >
1987 Deepest_Type_Access_Level (T)
1990 ("expression has deeper access level than component " &
1991 "(RM 3.10.2 (12.2))", E);
1994 -- The initialization expression is a reference to an access
1995 -- discriminant. The type of the discriminant is always deeper
1996 -- than any access type.
1998 if Ekind (Etype (E)) = E_Anonymous_Access_Type
1999 and then Is_Entity_Name (E)
2000 and then Ekind (Entity (E)) = E_In_Parameter
2001 and then Present (Discriminal_Link (Entity (E)))
2004 ("discriminant has deeper accessibility level than target",
2010 -- The parent type may be a private view with unknown discriminants,
2011 -- and thus unconstrained. Regular components must be constrained.
2013 if Is_Indefinite_Subtype (T) and then Chars (Id) /= Name_uParent then
2014 if Is_Class_Wide_Type (T) then
2016 ("class-wide subtype with unknown discriminants" &
2017 " in component declaration",
2018 Subtype_Indication (Component_Definition (N)));
2021 ("unconstrained subtype in component declaration",
2022 Subtype_Indication (Component_Definition (N)));
2025 -- Components cannot be abstract, except for the special case of
2026 -- the _Parent field (case of extending an abstract tagged type)
2028 elsif Is_Abstract_Type (T) and then Chars (Id) /= Name_uParent then
2029 Error_Msg_N ("type of a component cannot be abstract", N);
2033 Set_Is_Aliased (Id, Aliased_Present (Component_Definition (N)));
2035 -- The component declaration may have a per-object constraint, set
2036 -- the appropriate flag in the defining identifier of the subtype.
2038 if Present (Subtype_Indication (Component_Definition (N))) then
2040 Sindic : constant Node_Id :=
2041 Subtype_Indication (Component_Definition (N));
2043 if Nkind (Sindic) = N_Subtype_Indication
2044 and then Present (Constraint (Sindic))
2045 and then Contains_POC (Constraint (Sindic))
2047 Set_Has_Per_Object_Constraint (Id);
2052 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
2053 -- out some static checks.
2055 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
2056 Null_Exclusion_Static_Checks (N);
2059 -- If this component is private (or depends on a private type), flag the
2060 -- record type to indicate that some operations are not available.
2062 P := Private_Component (T);
2066 -- Check for circular definitions
2068 if P = Any_Type then
2069 Set_Etype (Id, Any_Type);
2071 -- There is a gap in the visibility of operations only if the
2072 -- component type is not defined in the scope of the record type.
2074 elsif Scope (P) = Scope (Current_Scope) then
2077 elsif Is_Limited_Type (P) then
2078 Set_Is_Limited_Composite (Current_Scope);
2081 Set_Is_Private_Composite (Current_Scope);
2086 and then Is_Limited_Type (T)
2087 and then Chars (Id) /= Name_uParent
2088 and then Is_Tagged_Type (Current_Scope)
2090 if Is_Derived_Type (Current_Scope)
2091 and then not Is_Known_Limited (Current_Scope)
2094 ("extension of nonlimited type cannot have limited components",
2097 if Is_Interface (Root_Type (Current_Scope)) then
2099 ("\limitedness is not inherited from limited interface", N);
2100 Error_Msg_N ("\add LIMITED to type indication", N);
2103 Explain_Limited_Type (T, N);
2104 Set_Etype (Id, Any_Type);
2105 Set_Is_Limited_Composite (Current_Scope, False);
2107 elsif not Is_Derived_Type (Current_Scope)
2108 and then not Is_Limited_Record (Current_Scope)
2109 and then not Is_Concurrent_Type (Current_Scope)
2112 ("nonlimited tagged type cannot have limited components", N);
2113 Explain_Limited_Type (T, N);
2114 Set_Etype (Id, Any_Type);
2115 Set_Is_Limited_Composite (Current_Scope, False);
2119 Set_Original_Record_Component (Id, Id);
2121 if Has_Aspects (N) then
2122 Analyze_Aspect_Specifications (N, Id);
2125 Analyze_Dimension (N);
2126 end Analyze_Component_Declaration;
2128 --------------------------
2129 -- Analyze_Declarations --
2130 --------------------------
2132 procedure Analyze_Declarations (L : List_Id) is
2135 procedure Adjust_Decl;
2136 -- Adjust Decl not to include implicit label declarations, since these
2137 -- have strange Sloc values that result in elaboration check problems.
2138 -- (They have the sloc of the label as found in the source, and that
2139 -- is ahead of the current declarative part).
2141 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id);
2142 -- Determine whether Body_Decl denotes the body of a late controlled
2143 -- primitive (either Initialize, Adjust or Finalize). If this is the
2144 -- case, add a proper spec if the body lacks one. The spec is inserted
2145 -- before Body_Decl and immedately analyzed.
2147 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id);
2148 -- Spec_Id is the entity of a package that may define abstract states.
2149 -- If the states have visible refinement, remove the visibility of each
2150 -- constituent at the end of the package body declarations.
2156 procedure Adjust_Decl is
2158 while Present (Prev (Decl))
2159 and then Nkind (Decl) = N_Implicit_Label_Declaration
2165 --------------------------------------
2166 -- Handle_Late_Controlled_Primitive --
2167 --------------------------------------
2169 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id) is
2170 Body_Spec : constant Node_Id := Specification (Body_Decl);
2171 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2172 Loc : constant Source_Ptr := Sloc (Body_Id);
2173 Params : constant List_Id :=
2174 Parameter_Specifications (Body_Spec);
2176 Spec_Id : Entity_Id;
2180 -- Consider only procedure bodies whose name matches one of the three
2181 -- controlled primitives.
2183 if Nkind (Body_Spec) /= N_Procedure_Specification
2184 or else not Nam_In (Chars (Body_Id), Name_Adjust,
2190 -- A controlled primitive must have exactly one formal which is not
2191 -- an anonymous access type.
2193 elsif List_Length (Params) /= 1 then
2197 Typ := Parameter_Type (First (Params));
2199 if Nkind (Typ) = N_Access_Definition then
2205 -- The type of the formal must be derived from [Limited_]Controlled
2207 if not Is_Controlled (Entity (Typ)) then
2211 -- Check whether a specification exists for this body. We do not
2212 -- analyze the spec of the body in full, because it will be analyzed
2213 -- again when the body is properly analyzed, and we cannot create
2214 -- duplicate entries in the formals chain. We look for an explicit
2215 -- specification because the body may be an overriding operation and
2216 -- an inherited spec may be present.
2218 Spec_Id := Current_Entity (Body_Id);
2220 while Present (Spec_Id) loop
2221 if Ekind_In (Spec_Id, E_Procedure, E_Generic_Procedure)
2222 and then Scope (Spec_Id) = Current_Scope
2223 and then Present (First_Formal (Spec_Id))
2224 and then No (Next_Formal (First_Formal (Spec_Id)))
2225 and then Etype (First_Formal (Spec_Id)) = Entity (Typ)
2226 and then Comes_From_Source (Spec_Id)
2231 Spec_Id := Homonym (Spec_Id);
2234 -- At this point the body is known to be a late controlled primitive.
2235 -- Generate a matching spec and insert it before the body. Note the
2236 -- use of Copy_Separate_Tree - we want an entirely separate semantic
2237 -- tree in this case.
2239 Spec := Copy_Separate_Tree (Body_Spec);
2241 -- Ensure that the subprogram declaration does not inherit the null
2242 -- indicator from the body as we now have a proper spec/body pair.
2244 Set_Null_Present (Spec, False);
2246 Insert_Before_And_Analyze (Body_Decl,
2247 Make_Subprogram_Declaration (Loc, Specification => Spec));
2248 end Handle_Late_Controlled_Primitive;
2250 --------------------------------
2251 -- Remove_Visible_Refinements --
2252 --------------------------------
2254 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id) is
2255 State_Elmt : Elmt_Id;
2257 if Present (Abstract_States (Spec_Id)) then
2258 State_Elmt := First_Elmt (Abstract_States (Spec_Id));
2259 while Present (State_Elmt) loop
2260 Set_Has_Visible_Refinement (Node (State_Elmt), False);
2261 Next_Elmt (State_Elmt);
2264 end Remove_Visible_Refinements;
2269 Freeze_From : Entity_Id := Empty;
2270 Next_Decl : Node_Id;
2271 Spec_Id : Entity_Id;
2273 Body_Seen : Boolean := False;
2274 -- Flag set when the first body [stub] is encountered
2276 In_Package_Body : Boolean := False;
2277 -- Flag set when the current declaration list belongs to a package body
2279 -- Start of processing for Analyze_Declarations
2282 if Restriction_Check_Required (SPARK_05) then
2283 Check_Later_Vs_Basic_Declarations (L, During_Parsing => False);
2287 while Present (Decl) loop
2289 -- Package spec cannot contain a package declaration in SPARK
2291 if Nkind (Decl) = N_Package_Declaration
2292 and then Nkind (Parent (L)) = N_Package_Specification
2294 Check_SPARK_05_Restriction
2295 ("package specification cannot contain a package declaration",
2299 -- Complete analysis of declaration
2302 Next_Decl := Next (Decl);
2304 if No (Freeze_From) then
2305 Freeze_From := First_Entity (Current_Scope);
2308 -- At the end of a declarative part, freeze remaining entities
2309 -- declared in it. The end of the visible declarations of package
2310 -- specification is not the end of a declarative part if private
2311 -- declarations are present. The end of a package declaration is a
2312 -- freezing point only if it a library package. A task definition or
2313 -- protected type definition is not a freeze point either. Finally,
2314 -- we do not freeze entities in generic scopes, because there is no
2315 -- code generated for them and freeze nodes will be generated for
2318 -- The end of a package instantiation is not a freeze point, but
2319 -- for now we make it one, because the generic body is inserted
2320 -- (currently) immediately after. Generic instantiations will not
2321 -- be a freeze point once delayed freezing of bodies is implemented.
2322 -- (This is needed in any case for early instantiations ???).
2324 if No (Next_Decl) then
2325 if Nkind_In (Parent (L), N_Component_List,
2327 N_Protected_Definition)
2331 elsif Nkind (Parent (L)) /= N_Package_Specification then
2332 if Nkind (Parent (L)) = N_Package_Body then
2333 Freeze_From := First_Entity (Current_Scope);
2336 -- There may have been several freezing points previously,
2337 -- for example object declarations or subprogram bodies, but
2338 -- at the end of a declarative part we check freezing from
2339 -- the beginning, even though entities may already be frozen,
2340 -- in order to perform visibility checks on delayed aspects.
2343 Freeze_All (First_Entity (Current_Scope), Decl);
2344 Freeze_From := Last_Entity (Current_Scope);
2346 elsif Scope (Current_Scope) /= Standard_Standard
2347 and then not Is_Child_Unit (Current_Scope)
2348 and then No (Generic_Parent (Parent (L)))
2352 elsif L /= Visible_Declarations (Parent (L))
2353 or else No (Private_Declarations (Parent (L)))
2354 or else Is_Empty_List (Private_Declarations (Parent (L)))
2357 Freeze_All (First_Entity (Current_Scope), Decl);
2358 Freeze_From := Last_Entity (Current_Scope);
2361 -- If next node is a body then freeze all types before the body.
2362 -- An exception occurs for some expander-generated bodies. If these
2363 -- are generated at places where in general language rules would not
2364 -- allow a freeze point, then we assume that the expander has
2365 -- explicitly checked that all required types are properly frozen,
2366 -- and we do not cause general freezing here. This special circuit
2367 -- is used when the encountered body is marked as having already
2370 -- In all other cases (bodies that come from source, and expander
2371 -- generated bodies that have not been analyzed yet), freeze all
2372 -- types now. Note that in the latter case, the expander must take
2373 -- care to attach the bodies at a proper place in the tree so as to
2374 -- not cause unwanted freezing at that point.
2376 elsif not Analyzed (Next_Decl) and then Is_Body (Next_Decl) then
2378 -- When a controlled type is frozen, the expander generates stream
2379 -- and controlled type support routines. If the freeze is caused
2380 -- by the stand alone body of Initialize, Adjust and Finalize, the
2381 -- expander will end up using the wrong version of these routines
2382 -- as the body has not been processed yet. To remedy this, detect
2383 -- a late controlled primitive and create a proper spec for it.
2384 -- This ensures that the primitive will override its inherited
2385 -- counterpart before the freeze takes place.
2387 -- If the declaration we just processed is a body, do not attempt
2388 -- to examine Next_Decl as the late primitive idiom can only apply
2389 -- to the first encountered body.
2391 -- The spec of the late primitive is not generated in ASIS mode to
2392 -- ensure a consistent list of primitives that indicates the true
2393 -- semantic structure of the program (which is not relevant when
2394 -- generating executable code.
2396 -- ??? a cleaner approach may be possible and/or this solution
2397 -- could be extended to general-purpose late primitives, TBD.
2399 if not ASIS_Mode and then not Body_Seen and then not Is_Body (Decl)
2403 if Nkind (Next_Decl) = N_Subprogram_Body then
2404 Handle_Late_Controlled_Primitive (Next_Decl);
2409 Freeze_All (Freeze_From, Decl);
2410 Freeze_From := Last_Entity (Current_Scope);
2416 -- Analyze the contracts of packages and their bodies
2419 Context := Parent (L);
2421 if Nkind (Context) = N_Package_Specification then
2423 -- When a package has private declarations, its contract must be
2424 -- analyzed at the end of the said declarations. This way both the
2425 -- analysis and freeze actions are properly synchronized in case
2426 -- of private type use within the contract.
2428 if L = Private_Declarations (Context) then
2429 Analyze_Package_Contract (Defining_Entity (Context));
2431 -- Build the bodies of the default initial condition procedures
2432 -- for all types subject to pragma Default_Initial_Condition.
2433 -- From a purely Ada stand point, this is a freezing activity,
2434 -- however freezing is not available under GNATprove_Mode. To
2435 -- accomodate both scenarios, the bodies are build at the end
2436 -- of private declaration analysis.
2438 Build_Default_Init_Cond_Procedure_Bodies (L);
2440 -- Otherwise the contract is analyzed at the end of the visible
2443 elsif L = Visible_Declarations (Context)
2444 and then No (Private_Declarations (Context))
2446 Analyze_Package_Contract (Defining_Entity (Context));
2449 elsif Nkind (Context) = N_Package_Body then
2450 In_Package_Body := True;
2451 Spec_Id := Corresponding_Spec (Context);
2453 Analyze_Package_Body_Contract (Defining_Entity (Context));
2457 -- Analyze the contracts of subprogram declarations, subprogram bodies
2458 -- and variables now due to the delayed visibility requirements of their
2462 while Present (Decl) loop
2463 if Nkind (Decl) = N_Object_Declaration then
2464 Analyze_Object_Contract (Defining_Entity (Decl));
2466 elsif Nkind_In (Decl, N_Abstract_Subprogram_Declaration,
2467 N_Subprogram_Declaration)
2469 Analyze_Subprogram_Contract (Defining_Entity (Decl));
2471 elsif Nkind (Decl) = N_Subprogram_Body then
2472 Analyze_Subprogram_Body_Contract (Defining_Entity (Decl));
2474 elsif Nkind (Decl) = N_Subprogram_Body_Stub then
2475 Analyze_Subprogram_Body_Stub_Contract (Defining_Entity (Decl));
2481 -- State refinements are visible upto the end the of the package body
2482 -- declarations. Hide the refinements from visibility to restore the
2483 -- original state conditions.
2485 if In_Package_Body then
2486 Remove_Visible_Refinements (Spec_Id);
2488 end Analyze_Declarations;
2490 -----------------------------------
2491 -- Analyze_Full_Type_Declaration --
2492 -----------------------------------
2494 procedure Analyze_Full_Type_Declaration (N : Node_Id) is
2495 Def : constant Node_Id := Type_Definition (N);
2496 Def_Id : constant Entity_Id := Defining_Identifier (N);
2500 Is_Remote : constant Boolean :=
2501 (Is_Remote_Types (Current_Scope)
2502 or else Is_Remote_Call_Interface (Current_Scope))
2503 and then not (In_Private_Part (Current_Scope)
2504 or else In_Package_Body (Current_Scope));
2506 procedure Check_Ops_From_Incomplete_Type;
2507 -- If there is a tagged incomplete partial view of the type, traverse
2508 -- the primitives of the incomplete view and change the type of any
2509 -- controlling formals and result to indicate the full view. The
2510 -- primitives will be added to the full type's primitive operations
2511 -- list later in Sem_Disp.Check_Operation_From_Incomplete_Type (which
2512 -- is called from Process_Incomplete_Dependents).
2514 ------------------------------------
2515 -- Check_Ops_From_Incomplete_Type --
2516 ------------------------------------
2518 procedure Check_Ops_From_Incomplete_Type is
2525 and then Ekind (Prev) = E_Incomplete_Type
2526 and then Is_Tagged_Type (Prev)
2527 and then Is_Tagged_Type (T)
2529 Elmt := First_Elmt (Primitive_Operations (Prev));
2530 while Present (Elmt) loop
2533 Formal := First_Formal (Op);
2534 while Present (Formal) loop
2535 if Etype (Formal) = Prev then
2536 Set_Etype (Formal, T);
2539 Next_Formal (Formal);
2542 if Etype (Op) = Prev then
2549 end Check_Ops_From_Incomplete_Type;
2551 -- Start of processing for Analyze_Full_Type_Declaration
2554 Prev := Find_Type_Name (N);
2556 -- The type declaration may be subject to pragma Ghost with policy
2557 -- Ignore. Set the mode now to ensure that any nodes generated during
2558 -- analysis and expansion are properly flagged as ignored Ghost.
2560 Set_Ghost_Mode (N, Prev);
2562 -- The full view, if present, now points to the current type. If there
2563 -- is an incomplete partial view, set a link to it, to simplify the
2564 -- retrieval of primitive operations of the type.
2566 -- Ada 2005 (AI-50217): If the type was previously decorated when
2567 -- imported through a LIMITED WITH clause, it appears as incomplete
2568 -- but has no full view.
2570 if Ekind (Prev) = E_Incomplete_Type
2571 and then Present (Full_View (Prev))
2573 T := Full_View (Prev);
2574 Set_Incomplete_View (N, Parent (Prev));
2579 Set_Is_Pure (T, Is_Pure (Current_Scope));
2581 -- We set the flag Is_First_Subtype here. It is needed to set the
2582 -- corresponding flag for the Implicit class-wide-type created
2583 -- during tagged types processing.
2585 Set_Is_First_Subtype (T, True);
2587 -- Only composite types other than array types are allowed to have
2592 -- For derived types, the rule will be checked once we've figured
2593 -- out the parent type.
2595 when N_Derived_Type_Definition =>
2598 -- For record types, discriminants are allowed, unless we are in
2601 when N_Record_Definition =>
2602 if Present (Discriminant_Specifications (N)) then
2603 Check_SPARK_05_Restriction
2604 ("discriminant type is not allowed",
2606 (First (Discriminant_Specifications (N))));
2610 if Present (Discriminant_Specifications (N)) then
2612 ("elementary or array type cannot have discriminants",
2614 (First (Discriminant_Specifications (N))));
2618 -- Elaborate the type definition according to kind, and generate
2619 -- subsidiary (implicit) subtypes where needed. We skip this if it was
2620 -- already done (this happens during the reanalysis that follows a call
2621 -- to the high level optimizer).
2623 if not Analyzed (T) then
2627 when N_Access_To_Subprogram_Definition =>
2628 Access_Subprogram_Declaration (T, Def);
2630 -- If this is a remote access to subprogram, we must create the
2631 -- equivalent fat pointer type, and related subprograms.
2634 Process_Remote_AST_Declaration (N);
2637 -- Validate categorization rule against access type declaration
2638 -- usually a violation in Pure unit, Shared_Passive unit.
2640 Validate_Access_Type_Declaration (T, N);
2642 when N_Access_To_Object_Definition =>
2643 Access_Type_Declaration (T, Def);
2645 -- Validate categorization rule against access type declaration
2646 -- usually a violation in Pure unit, Shared_Passive unit.
2648 Validate_Access_Type_Declaration (T, N);
2650 -- If we are in a Remote_Call_Interface package and define a
2651 -- RACW, then calling stubs and specific stream attributes
2655 and then Is_Remote_Access_To_Class_Wide_Type (Def_Id)
2657 Add_RACW_Features (Def_Id);
2660 -- Set no strict aliasing flag if config pragma seen
2662 if Opt.No_Strict_Aliasing then
2663 Set_No_Strict_Aliasing (Base_Type (Def_Id));
2666 when N_Array_Type_Definition =>
2667 Array_Type_Declaration (T, Def);
2669 when N_Derived_Type_Definition =>
2670 Derived_Type_Declaration (T, N, T /= Def_Id);
2672 when N_Enumeration_Type_Definition =>
2673 Enumeration_Type_Declaration (T, Def);
2675 when N_Floating_Point_Definition =>
2676 Floating_Point_Type_Declaration (T, Def);
2678 when N_Decimal_Fixed_Point_Definition =>
2679 Decimal_Fixed_Point_Type_Declaration (T, Def);
2681 when N_Ordinary_Fixed_Point_Definition =>
2682 Ordinary_Fixed_Point_Type_Declaration (T, Def);
2684 when N_Signed_Integer_Type_Definition =>
2685 Signed_Integer_Type_Declaration (T, Def);
2687 when N_Modular_Type_Definition =>
2688 Modular_Type_Declaration (T, Def);
2690 when N_Record_Definition =>
2691 Record_Type_Declaration (T, N, Prev);
2693 -- If declaration has a parse error, nothing to elaborate.
2699 raise Program_Error;
2704 if Etype (T) = Any_Type then
2708 -- Controlled type is not allowed in SPARK
2710 if Is_Visibly_Controlled (T) then
2711 Check_SPARK_05_Restriction ("controlled type is not allowed", N);
2714 -- A type declared within a Ghost region is automatically Ghost
2715 -- (SPARK RM 6.9(2)).
2717 if Comes_From_Source (T) and then Ghost_Mode > None then
2718 Set_Is_Ghost_Entity (T);
2721 -- Some common processing for all types
2723 Set_Depends_On_Private (T, Has_Private_Component (T));
2724 Check_Ops_From_Incomplete_Type;
2726 -- Both the declared entity, and its anonymous base type if one was
2727 -- created, need freeze nodes allocated.
2730 B : constant Entity_Id := Base_Type (T);
2733 -- In the case where the base type differs from the first subtype, we
2734 -- pre-allocate a freeze node, and set the proper link to the first
2735 -- subtype. Freeze_Entity will use this preallocated freeze node when
2736 -- it freezes the entity.
2738 -- This does not apply if the base type is a generic type, whose
2739 -- declaration is independent of the current derived definition.
2741 if B /= T and then not Is_Generic_Type (B) then
2742 Ensure_Freeze_Node (B);
2743 Set_First_Subtype_Link (Freeze_Node (B), T);
2746 -- A type that is imported through a limited_with clause cannot
2747 -- generate any code, and thus need not be frozen. However, an access
2748 -- type with an imported designated type needs a finalization list,
2749 -- which may be referenced in some other package that has non-limited
2750 -- visibility on the designated type. Thus we must create the
2751 -- finalization list at the point the access type is frozen, to
2752 -- prevent unsatisfied references at link time.
2754 if not From_Limited_With (T) or else Is_Access_Type (T) then
2755 Set_Has_Delayed_Freeze (T);
2759 -- Case where T is the full declaration of some private type which has
2760 -- been swapped in Defining_Identifier (N).
2762 if T /= Def_Id and then Is_Private_Type (Def_Id) then
2763 Process_Full_View (N, T, Def_Id);
2765 -- Record the reference. The form of this is a little strange, since
2766 -- the full declaration has been swapped in. So the first parameter
2767 -- here represents the entity to which a reference is made which is
2768 -- the "real" entity, i.e. the one swapped in, and the second
2769 -- parameter provides the reference location.
2771 -- Also, we want to kill Has_Pragma_Unreferenced temporarily here
2772 -- since we don't want a complaint about the full type being an
2773 -- unwanted reference to the private type
2776 B : constant Boolean := Has_Pragma_Unreferenced (T);
2778 Set_Has_Pragma_Unreferenced (T, False);
2779 Generate_Reference (T, T, 'c');
2780 Set_Has_Pragma_Unreferenced (T, B);
2783 Set_Completion_Referenced (Def_Id);
2785 -- For completion of incomplete type, process incomplete dependents
2786 -- and always mark the full type as referenced (it is the incomplete
2787 -- type that we get for any real reference).
2789 elsif Ekind (Prev) = E_Incomplete_Type then
2790 Process_Incomplete_Dependents (N, T, Prev);
2791 Generate_Reference (Prev, Def_Id, 'c');
2792 Set_Completion_Referenced (Def_Id);
2794 -- If not private type or incomplete type completion, this is a real
2795 -- definition of a new entity, so record it.
2798 Generate_Definition (Def_Id);
2801 if Chars (Scope (Def_Id)) = Name_System
2802 and then Chars (Def_Id) = Name_Address
2803 and then Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (N)))
2805 Set_Is_Descendent_Of_Address (Def_Id);
2806 Set_Is_Descendent_Of_Address (Base_Type (Def_Id));
2807 Set_Is_Descendent_Of_Address (Prev);
2810 Set_Optimize_Alignment_Flags (Def_Id);
2811 Check_Eliminated (Def_Id);
2813 -- If the declaration is a completion and aspects are present, apply
2814 -- them to the entity for the type which is currently the partial
2815 -- view, but which is the one that will be frozen.
2817 if Has_Aspects (N) then
2819 -- In most cases the partial view is a private type, and both views
2820 -- appear in different declarative parts. In the unusual case where
2821 -- the partial view is incomplete, perform the analysis on the
2822 -- full view, to prevent freezing anomalies with the corresponding
2823 -- class-wide type, which otherwise might be frozen before the
2824 -- dispatch table is built.
2827 and then Ekind (Prev) /= E_Incomplete_Type
2829 Analyze_Aspect_Specifications (N, Prev);
2834 Analyze_Aspect_Specifications (N, Def_Id);
2837 end Analyze_Full_Type_Declaration;
2839 ----------------------------------
2840 -- Analyze_Incomplete_Type_Decl --
2841 ----------------------------------
2843 procedure Analyze_Incomplete_Type_Decl (N : Node_Id) is
2844 F : constant Boolean := Is_Pure (Current_Scope);
2848 Check_SPARK_05_Restriction ("incomplete type is not allowed", N);
2850 Generate_Definition (Defining_Identifier (N));
2852 -- Process an incomplete declaration. The identifier must not have been
2853 -- declared already in the scope. However, an incomplete declaration may
2854 -- appear in the private part of a package, for a private type that has
2855 -- already been declared.
2857 -- In this case, the discriminants (if any) must match
2859 T := Find_Type_Name (N);
2861 Set_Ekind (T, E_Incomplete_Type);
2862 Init_Size_Align (T);
2863 Set_Is_First_Subtype (T, True);
2866 -- An incomplete type declared within a Ghost region is automatically
2867 -- Ghost (SPARK RM 6.9(2)).
2869 if Ghost_Mode > None then
2870 Set_Is_Ghost_Entity (T);
2873 -- Ada 2005 (AI-326): Minimum decoration to give support to tagged
2874 -- incomplete types.
2876 if Tagged_Present (N) then
2877 Set_Is_Tagged_Type (T, True);
2878 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
2879 Make_Class_Wide_Type (T);
2880 Set_Direct_Primitive_Operations (T, New_Elmt_List);
2885 Set_Stored_Constraint (T, No_Elist);
2887 if Present (Discriminant_Specifications (N)) then
2888 Process_Discriminants (N);
2893 -- If the type has discriminants, non-trivial subtypes may be
2894 -- declared before the full view of the type. The full views of those
2895 -- subtypes will be built after the full view of the type.
2897 Set_Private_Dependents (T, New_Elmt_List);
2899 end Analyze_Incomplete_Type_Decl;
2901 -----------------------------------
2902 -- Analyze_Interface_Declaration --
2903 -----------------------------------
2905 procedure Analyze_Interface_Declaration (T : Entity_Id; Def : Node_Id) is
2906 CW : constant Entity_Id := Class_Wide_Type (T);
2909 Set_Is_Tagged_Type (T);
2910 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
2912 Set_Is_Limited_Record (T, Limited_Present (Def)
2913 or else Task_Present (Def)
2914 or else Protected_Present (Def)
2915 or else Synchronized_Present (Def));
2917 -- Type is abstract if full declaration carries keyword, or if previous
2918 -- partial view did.
2920 Set_Is_Abstract_Type (T);
2921 Set_Is_Interface (T);
2923 -- Type is a limited interface if it includes the keyword limited, task,
2924 -- protected, or synchronized.
2926 Set_Is_Limited_Interface
2927 (T, Limited_Present (Def)
2928 or else Protected_Present (Def)
2929 or else Synchronized_Present (Def)
2930 or else Task_Present (Def));
2932 Set_Interfaces (T, New_Elmt_List);
2933 Set_Direct_Primitive_Operations (T, New_Elmt_List);
2935 -- Complete the decoration of the class-wide entity if it was already
2936 -- built (i.e. during the creation of the limited view)
2938 if Present (CW) then
2939 Set_Is_Interface (CW);
2940 Set_Is_Limited_Interface (CW, Is_Limited_Interface (T));
2943 -- Check runtime support for synchronized interfaces
2945 if VM_Target = No_VM
2946 and then (Is_Task_Interface (T)
2947 or else Is_Protected_Interface (T)
2948 or else Is_Synchronized_Interface (T))
2949 and then not RTE_Available (RE_Select_Specific_Data)
2951 Error_Msg_CRT ("synchronized interfaces", T);
2953 end Analyze_Interface_Declaration;
2955 -----------------------------
2956 -- Analyze_Itype_Reference --
2957 -----------------------------
2959 -- Nothing to do. This node is placed in the tree only for the benefit of
2960 -- back end processing, and has no effect on the semantic processing.
2962 procedure Analyze_Itype_Reference (N : Node_Id) is
2964 pragma Assert (Is_Itype (Itype (N)));
2966 end Analyze_Itype_Reference;
2968 --------------------------------
2969 -- Analyze_Number_Declaration --
2970 --------------------------------
2972 procedure Analyze_Number_Declaration (N : Node_Id) is
2973 Id : constant Entity_Id := Defining_Identifier (N);
2974 E : constant Node_Id := Expression (N);
2976 Index : Interp_Index;
2980 -- The number declaration may be subject to pragma Ghost with policy
2981 -- Ignore. Set the mode now to ensure that any nodes generated during
2982 -- analysis and expansion are properly flagged as ignored Ghost.
2986 Generate_Definition (Id);
2989 -- A number declared within a Ghost region is automatically Ghost
2990 -- (SPARK RM 6.9(2)).
2992 if Ghost_Mode > None then
2993 Set_Is_Ghost_Entity (Id);
2996 -- This is an optimization of a common case of an integer literal
2998 if Nkind (E) = N_Integer_Literal then
2999 Set_Is_Static_Expression (E, True);
3000 Set_Etype (E, Universal_Integer);
3002 Set_Etype (Id, Universal_Integer);
3003 Set_Ekind (Id, E_Named_Integer);
3004 Set_Is_Frozen (Id, True);
3008 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3010 -- Process expression, replacing error by integer zero, to avoid
3011 -- cascaded errors or aborts further along in the processing
3013 -- Replace Error by integer zero, which seems least likely to cause
3017 Rewrite (E, Make_Integer_Literal (Sloc (E), Uint_0));
3018 Set_Error_Posted (E);
3023 -- Verify that the expression is static and numeric. If
3024 -- the expression is overloaded, we apply the preference
3025 -- rule that favors root numeric types.
3027 if not Is_Overloaded (E) then
3029 if Has_Dynamic_Predicate_Aspect (T) then
3031 ("subtype has dynamic predicate, "
3032 & "not allowed in number declaration", N);
3038 Get_First_Interp (E, Index, It);
3039 while Present (It.Typ) loop
3040 if (Is_Integer_Type (It.Typ) or else Is_Real_Type (It.Typ))
3041 and then (Scope (Base_Type (It.Typ))) = Standard_Standard
3043 if T = Any_Type then
3046 elsif It.Typ = Universal_Real
3048 It.Typ = Universal_Integer
3050 -- Choose universal interpretation over any other
3057 Get_Next_Interp (Index, It);
3061 if Is_Integer_Type (T) then
3063 Set_Etype (Id, Universal_Integer);
3064 Set_Ekind (Id, E_Named_Integer);
3066 elsif Is_Real_Type (T) then
3068 -- Because the real value is converted to universal_real, this is a
3069 -- legal context for a universal fixed expression.
3071 if T = Universal_Fixed then
3073 Loc : constant Source_Ptr := Sloc (N);
3074 Conv : constant Node_Id := Make_Type_Conversion (Loc,
3076 New_Occurrence_Of (Universal_Real, Loc),
3077 Expression => Relocate_Node (E));
3084 elsif T = Any_Fixed then
3085 Error_Msg_N ("illegal context for mixed mode operation", E);
3087 -- Expression is of the form : universal_fixed * integer. Try to
3088 -- resolve as universal_real.
3090 T := Universal_Real;
3095 Set_Etype (Id, Universal_Real);
3096 Set_Ekind (Id, E_Named_Real);
3099 Wrong_Type (E, Any_Numeric);
3103 Set_Ekind (Id, E_Constant);
3104 Set_Never_Set_In_Source (Id, True);
3105 Set_Is_True_Constant (Id, True);
3109 if Nkind_In (E, N_Integer_Literal, N_Real_Literal) then
3110 Set_Etype (E, Etype (Id));
3113 if not Is_OK_Static_Expression (E) then
3114 Flag_Non_Static_Expr
3115 ("non-static expression used in number declaration!", E);
3116 Rewrite (E, Make_Integer_Literal (Sloc (N), 1));
3117 Set_Etype (E, Any_Type);
3119 end Analyze_Number_Declaration;
3121 -----------------------------
3122 -- Analyze_Object_Contract --
3123 -----------------------------
3125 procedure Analyze_Object_Contract (Obj_Id : Entity_Id) is
3126 Obj_Typ : constant Entity_Id := Etype (Obj_Id);
3127 AR_Val : Boolean := False;
3128 AW_Val : Boolean := False;
3129 ER_Val : Boolean := False;
3130 EW_Val : Boolean := False;
3132 Seen : Boolean := False;
3135 -- The loop parameter in an element iterator over a formal container
3136 -- is declared with an object declaration but no contracts apply.
3138 if Ekind (Obj_Id) = E_Loop_Parameter then
3142 if Ekind (Obj_Id) = E_Constant then
3144 -- A constant cannot be effectively volatile. This check is only
3145 -- relevant with SPARK_Mode on as it is not a standard Ada legality
3146 -- rule. Do not flag internally-generated constants that map generic
3147 -- formals to actuals in instantiations (SPARK RM 7.1.3(6)).
3150 and then Is_Effectively_Volatile (Obj_Id)
3151 and then No (Corresponding_Generic_Association (Parent (Obj_Id)))
3153 Error_Msg_N ("constant cannot be volatile", Obj_Id);
3156 else pragma Assert (Ekind (Obj_Id) = E_Variable);
3158 -- The following checks are only relevant when SPARK_Mode is on as
3159 -- they are not standard Ada legality rules. Internally generated
3160 -- temporaries are ignored.
3162 if SPARK_Mode = On and then Comes_From_Source (Obj_Id) then
3163 if Is_Effectively_Volatile (Obj_Id) then
3165 -- The declaration of an effectively volatile object must
3166 -- appear at the library level (SPARK RM 7.1.3(7), C.6(6)).
3168 if not Is_Library_Level_Entity (Obj_Id) then
3170 ("volatile variable & must be declared at library level",
3173 -- An object of a discriminated type cannot be effectively
3174 -- volatile (SPARK RM C.6(4)).
3176 elsif Has_Discriminants (Obj_Typ) then
3178 ("discriminated object & cannot be volatile", Obj_Id);
3180 -- An object of a tagged type cannot be effectively volatile
3181 -- (SPARK RM C.6(5)).
3183 elsif Is_Tagged_Type (Obj_Typ) then
3184 Error_Msg_N ("tagged object & cannot be volatile", Obj_Id);
3187 -- The object is not effectively volatile
3190 -- A non-effectively volatile object cannot have effectively
3191 -- volatile components (SPARK RM 7.1.3(7)).
3193 if not Is_Effectively_Volatile (Obj_Id)
3194 and then Has_Volatile_Component (Obj_Typ)
3197 ("non-volatile object & cannot have volatile components",
3203 if Is_Ghost_Entity (Obj_Id) then
3205 -- A Ghost object cannot be effectively volatile (SPARK RM 6.9(8))
3207 if Is_Effectively_Volatile (Obj_Id) then
3208 Error_Msg_N ("ghost variable & cannot be volatile", Obj_Id);
3210 -- A Ghost object cannot be imported or exported (SPARK RM 6.9(8))
3212 elsif Is_Imported (Obj_Id) then
3213 Error_Msg_N ("ghost object & cannot be imported", Obj_Id);
3215 elsif Is_Exported (Obj_Id) then
3216 Error_Msg_N ("ghost object & cannot be exported", Obj_Id);
3220 -- Analyze all external properties
3222 Prag := Get_Pragma (Obj_Id, Pragma_Async_Readers);
3224 if Present (Prag) then
3225 Analyze_External_Property_In_Decl_Part (Prag, AR_Val);
3229 Prag := Get_Pragma (Obj_Id, Pragma_Async_Writers);
3231 if Present (Prag) then
3232 Analyze_External_Property_In_Decl_Part (Prag, AW_Val);
3236 Prag := Get_Pragma (Obj_Id, Pragma_Effective_Reads);
3238 if Present (Prag) then
3239 Analyze_External_Property_In_Decl_Part (Prag, ER_Val);
3243 Prag := Get_Pragma (Obj_Id, Pragma_Effective_Writes);
3245 if Present (Prag) then
3246 Analyze_External_Property_In_Decl_Part (Prag, EW_Val);
3250 -- Verify the mutual interaction of the various external properties
3253 Check_External_Properties (Obj_Id, AR_Val, AW_Val, ER_Val, EW_Val);
3256 -- Check whether the lack of indicator Part_Of agrees with the
3257 -- placement of the variable with respect to the state space.
3259 Prag := Get_Pragma (Obj_Id, Pragma_Part_Of);
3262 Check_Missing_Part_Of (Obj_Id);
3266 -- A ghost object cannot be imported or exported (SPARK RM 6.9(8))
3268 if Is_Ghost_Entity (Obj_Id) then
3269 if Is_Exported (Obj_Id) then
3270 Error_Msg_N ("ghost object & cannot be exported", Obj_Id);
3272 elsif Is_Imported (Obj_Id) then
3273 Error_Msg_N ("ghost object & cannot be imported", Obj_Id);
3276 end Analyze_Object_Contract;
3278 --------------------------------
3279 -- Analyze_Object_Declaration --
3280 --------------------------------
3282 procedure Analyze_Object_Declaration (N : Node_Id) is
3283 Loc : constant Source_Ptr := Sloc (N);
3284 Id : constant Entity_Id := Defining_Identifier (N);
3288 E : Node_Id := Expression (N);
3289 -- E is set to Expression (N) throughout this routine. When
3290 -- Expression (N) is modified, E is changed accordingly.
3292 Prev_Entity : Entity_Id := Empty;
3294 function Count_Tasks (T : Entity_Id) return Uint;
3295 -- This function is called when a non-generic library level object of a
3296 -- task type is declared. Its function is to count the static number of
3297 -- tasks declared within the type (it is only called if Has_Tasks is set
3298 -- for T). As a side effect, if an array of tasks with non-static bounds
3299 -- or a variant record type is encountered, Check_Restrictions is called
3300 -- indicating the count is unknown.
3306 function Count_Tasks (T : Entity_Id) return Uint is
3312 if Is_Task_Type (T) then
3315 elsif Is_Record_Type (T) then
3316 if Has_Discriminants (T) then
3317 Check_Restriction (Max_Tasks, N);
3322 C := First_Component (T);
3323 while Present (C) loop
3324 V := V + Count_Tasks (Etype (C));
3331 elsif Is_Array_Type (T) then
3332 X := First_Index (T);
3333 V := Count_Tasks (Component_Type (T));
3334 while Present (X) loop
3337 if not Is_OK_Static_Subtype (C) then
3338 Check_Restriction (Max_Tasks, N);
3341 V := V * (UI_Max (Uint_0,
3342 Expr_Value (Type_High_Bound (C)) -
3343 Expr_Value (Type_Low_Bound (C)) + Uint_1));
3356 -- Start of processing for Analyze_Object_Declaration
3359 -- There are three kinds of implicit types generated by an
3360 -- object declaration:
3362 -- 1. Those generated by the original Object Definition
3364 -- 2. Those generated by the Expression
3366 -- 3. Those used to constrain the Object Definition with the
3367 -- expression constraints when the definition is unconstrained.
3369 -- They must be generated in this order to avoid order of elaboration
3370 -- issues. Thus the first step (after entering the name) is to analyze
3371 -- the object definition.
3373 if Constant_Present (N) then
3374 Prev_Entity := Current_Entity_In_Scope (Id);
3376 if Present (Prev_Entity)
3378 -- If the homograph is an implicit subprogram, it is overridden
3379 -- by the current declaration.
3381 ((Is_Overloadable (Prev_Entity)
3382 and then Is_Inherited_Operation (Prev_Entity))
3384 -- The current object is a discriminal generated for an entry
3385 -- family index. Even though the index is a constant, in this
3386 -- particular context there is no true constant redeclaration.
3387 -- Enter_Name will handle the visibility.
3390 (Is_Discriminal (Id)
3391 and then Ekind (Discriminal_Link (Id)) =
3392 E_Entry_Index_Parameter)
3394 -- The current object is the renaming for a generic declared
3395 -- within the instance.
3398 (Ekind (Prev_Entity) = E_Package
3399 and then Nkind (Parent (Prev_Entity)) =
3400 N_Package_Renaming_Declaration
3401 and then not Comes_From_Source (Prev_Entity)
3403 Is_Generic_Instance (Renamed_Entity (Prev_Entity))))
3405 Prev_Entity := Empty;
3409 -- The object declaration may be subject to pragma Ghost with policy
3410 -- Ignore. Set the mode now to ensure that any nodes generated during
3411 -- analysis and expansion are properly flagged as ignored Ghost.
3413 Set_Ghost_Mode (N, Prev_Entity);
3415 if Present (Prev_Entity) then
3416 Constant_Redeclaration (Id, N, T);
3418 Generate_Reference (Prev_Entity, Id, 'c');
3419 Set_Completion_Referenced (Id);
3421 if Error_Posted (N) then
3423 -- Type mismatch or illegal redeclaration, Do not analyze
3424 -- expression to avoid cascaded errors.
3426 T := Find_Type_Of_Object (Object_Definition (N), N);
3428 Set_Ekind (Id, E_Variable);
3432 -- In the normal case, enter identifier at the start to catch premature
3433 -- usage in the initialization expression.
3436 Generate_Definition (Id);
3439 Mark_Coextensions (N, Object_Definition (N));
3441 T := Find_Type_Of_Object (Object_Definition (N), N);
3443 if Nkind (Object_Definition (N)) = N_Access_Definition
3445 (Access_To_Subprogram_Definition (Object_Definition (N)))
3446 and then Protected_Present
3447 (Access_To_Subprogram_Definition (Object_Definition (N)))
3449 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
3452 if Error_Posted (Id) then
3454 Set_Ekind (Id, E_Variable);
3459 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
3460 -- out some static checks
3462 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
3464 -- In case of aggregates we must also take care of the correct
3465 -- initialization of nested aggregates bug this is done at the
3466 -- point of the analysis of the aggregate (see sem_aggr.adb).
3468 if Present (Expression (N))
3469 and then Nkind (Expression (N)) = N_Aggregate
3475 Save_Typ : constant Entity_Id := Etype (Id);
3477 Set_Etype (Id, T); -- Temp. decoration for static checks
3478 Null_Exclusion_Static_Checks (N);
3479 Set_Etype (Id, Save_Typ);
3484 -- Object is marked pure if it is in a pure scope
3486 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3488 -- If deferred constant, make sure context is appropriate. We detect
3489 -- a deferred constant as a constant declaration with no expression.
3490 -- A deferred constant can appear in a package body if its completion
3491 -- is by means of an interface pragma.
3493 if Constant_Present (N) and then No (E) then
3495 -- A deferred constant may appear in the declarative part of the
3496 -- following constructs:
3500 -- extended return statements
3503 -- subprogram bodies
3506 -- When declared inside a package spec, a deferred constant must be
3507 -- completed by a full constant declaration or pragma Import. In all
3508 -- other cases, the only proper completion is pragma Import. Extended
3509 -- return statements are flagged as invalid contexts because they do
3510 -- not have a declarative part and so cannot accommodate the pragma.
3512 if Ekind (Current_Scope) = E_Return_Statement then
3514 ("invalid context for deferred constant declaration (RM 7.4)",
3517 ("\declaration requires an initialization expression",
3519 Set_Constant_Present (N, False);
3521 -- In Ada 83, deferred constant must be of private type
3523 elsif not Is_Private_Type (T) then
3524 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
3526 ("(Ada 83) deferred constant must be private type", N);
3530 -- If not a deferred constant, then the object declaration freezes
3531 -- its type, unless the object is of an anonymous type and has delayed
3532 -- aspects. In that case the type is frozen when the object itself is.
3535 Check_Fully_Declared (T, N);
3537 if Has_Delayed_Aspects (Id)
3538 and then Is_Array_Type (T)
3539 and then Is_Itype (T)
3541 Set_Has_Delayed_Freeze (T);
3543 Freeze_Before (N, T);
3547 -- If the object was created by a constrained array definition, then
3548 -- set the link in both the anonymous base type and anonymous subtype
3549 -- that are built to represent the array type to point to the object.
3551 if Nkind (Object_Definition (Declaration_Node (Id))) =
3552 N_Constrained_Array_Definition
3554 Set_Related_Array_Object (T, Id);
3555 Set_Related_Array_Object (Base_Type (T), Id);
3558 -- Special checks for protected objects not at library level
3560 if Is_Protected_Type (T)
3561 and then not Is_Library_Level_Entity (Id)
3563 Check_Restriction (No_Local_Protected_Objects, Id);
3565 -- Protected objects with interrupt handlers must be at library level
3567 -- Ada 2005: This test is not needed (and the corresponding clause
3568 -- in the RM is removed) because accessibility checks are sufficient
3569 -- to make handlers not at the library level illegal.
3571 -- AI05-0303: The AI is in fact a binding interpretation, and thus
3572 -- applies to the '95 version of the language as well.
3574 if Has_Interrupt_Handler (T) and then Ada_Version < Ada_95 then
3576 ("interrupt object can only be declared at library level", Id);
3580 -- The actual subtype of the object is the nominal subtype, unless
3581 -- the nominal one is unconstrained and obtained from the expression.
3585 -- These checks should be performed before the initialization expression
3586 -- is considered, so that the Object_Definition node is still the same
3587 -- as in source code.
3589 -- In SPARK, the nominal subtype is always given by a subtype mark
3590 -- and must not be unconstrained. (The only exception to this is the
3591 -- acceptance of declarations of constants of type String.)
3593 if not Nkind_In (Object_Definition (N), N_Expanded_Name, N_Identifier)
3595 Check_SPARK_05_Restriction
3596 ("subtype mark required", Object_Definition (N));
3598 elsif Is_Array_Type (T)
3599 and then not Is_Constrained (T)
3600 and then T /= Standard_String
3602 Check_SPARK_05_Restriction
3603 ("subtype mark of constrained type expected",
3604 Object_Definition (N));
3607 -- There are no aliased objects in SPARK
3609 if Aliased_Present (N) then
3610 Check_SPARK_05_Restriction ("aliased object is not allowed", N);
3613 -- Process initialization expression if present and not in error
3615 if Present (E) and then E /= Error then
3617 -- Generate an error in case of CPP class-wide object initialization.
3618 -- Required because otherwise the expansion of the class-wide
3619 -- assignment would try to use 'size to initialize the object
3620 -- (primitive that is not available in CPP tagged types).
3622 if Is_Class_Wide_Type (Act_T)
3624 (Is_CPP_Class (Root_Type (Etype (Act_T)))
3626 (Present (Full_View (Root_Type (Etype (Act_T))))
3628 Is_CPP_Class (Full_View (Root_Type (Etype (Act_T))))))
3631 ("predefined assignment not available for 'C'P'P tagged types",
3635 Mark_Coextensions (N, E);
3638 -- In case of errors detected in the analysis of the expression,
3639 -- decorate it with the expected type to avoid cascaded errors
3641 if No (Etype (E)) then
3645 -- If an initialization expression is present, then we set the
3646 -- Is_True_Constant flag. It will be reset if this is a variable
3647 -- and it is indeed modified.
3649 Set_Is_True_Constant (Id, True);
3651 -- If we are analyzing a constant declaration, set its completion
3652 -- flag after analyzing and resolving the expression.
3654 if Constant_Present (N) then
3655 Set_Has_Completion (Id);
3658 -- Set type and resolve (type may be overridden later on). Note:
3659 -- Ekind (Id) must still be E_Void at this point so that incorrect
3660 -- early usage within E is properly diagnosed.
3664 -- If the expression is an aggregate we must look ahead to detect
3665 -- the possible presence of an address clause, and defer resolution
3666 -- and expansion of the aggregate to the freeze point of the entity.
3668 if Comes_From_Source (N)
3669 and then Expander_Active
3670 and then Nkind (E) = N_Aggregate
3671 and then Present (Following_Address_Clause (N))
3679 -- No further action needed if E is a call to an inlined function
3680 -- which returns an unconstrained type and it has been expanded into
3681 -- a procedure call. In that case N has been replaced by an object
3682 -- declaration without initializing expression and it has been
3683 -- analyzed (see Expand_Inlined_Call).
3685 if Back_End_Inlining
3686 and then Expander_Active
3687 and then Nkind (E) = N_Function_Call
3688 and then Nkind (Name (E)) in N_Has_Entity
3689 and then Is_Inlined (Entity (Name (E)))
3690 and then not Is_Constrained (Etype (E))
3691 and then Analyzed (N)
3692 and then No (Expression (N))
3697 -- If E is null and has been replaced by an N_Raise_Constraint_Error
3698 -- node (which was marked already-analyzed), we need to set the type
3699 -- to something other than Any_Access in order to keep gigi happy.
3701 if Etype (E) = Any_Access then
3705 -- If the object is an access to variable, the initialization
3706 -- expression cannot be an access to constant.
3708 if Is_Access_Type (T)
3709 and then not Is_Access_Constant (T)
3710 and then Is_Access_Type (Etype (E))
3711 and then Is_Access_Constant (Etype (E))
3714 ("access to variable cannot be initialized with an "
3715 & "access-to-constant expression", E);
3718 if not Assignment_OK (N) then
3719 Check_Initialization (T, E);
3722 Check_Unset_Reference (E);
3724 -- If this is a variable, then set current value. If this is a
3725 -- declared constant of a scalar type with a static expression,
3726 -- indicate that it is always valid.
3728 if not Constant_Present (N) then
3729 if Compile_Time_Known_Value (E) then
3730 Set_Current_Value (Id, E);
3733 elsif Is_Scalar_Type (T) and then Is_OK_Static_Expression (E) then
3734 Set_Is_Known_Valid (Id);
3737 -- Deal with setting of null flags
3739 if Is_Access_Type (T) then
3740 if Known_Non_Null (E) then
3741 Set_Is_Known_Non_Null (Id, True);
3742 elsif Known_Null (E) and then not Can_Never_Be_Null (Id) then
3743 Set_Is_Known_Null (Id, True);
3747 -- Check incorrect use of dynamically tagged expressions
3749 if Is_Tagged_Type (T) then
3750 Check_Dynamically_Tagged_Expression
3756 Apply_Scalar_Range_Check (E, T);
3757 Apply_Static_Length_Check (E, T);
3759 if Nkind (Original_Node (N)) = N_Object_Declaration
3760 and then Comes_From_Source (Original_Node (N))
3762 -- Only call test if needed
3764 and then Restriction_Check_Required (SPARK_05)
3765 and then not Is_SPARK_05_Initialization_Expr (Original_Node (E))
3767 Check_SPARK_05_Restriction
3768 ("initialization expression is not appropriate", E);
3771 -- A formal parameter of a specific tagged type whose related
3772 -- subprogram is subject to pragma Extensions_Visible with value
3773 -- "False" cannot be implicitly converted to a class-wide type by
3774 -- means of an initialization expression (SPARK RM 6.1.7(3)).
3776 if Is_Class_Wide_Type (T) and then Is_EVF_Expression (E) then
3778 ("formal parameter with Extensions_Visible False cannot be "
3779 & "implicitly converted to class-wide type", E);
3783 -- If the No_Streams restriction is set, check that the type of the
3784 -- object is not, and does not contain, any subtype derived from
3785 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
3786 -- Has_Stream just for efficiency reasons. There is no point in
3787 -- spending time on a Has_Stream check if the restriction is not set.
3789 if Restriction_Check_Required (No_Streams) then
3790 if Has_Stream (T) then
3791 Check_Restriction (No_Streams, N);
3795 -- Deal with predicate check before we start to do major rewriting. It
3796 -- is OK to initialize and then check the initialized value, since the
3797 -- object goes out of scope if we get a predicate failure. Note that we
3798 -- do this in the analyzer and not the expander because the analyzer
3799 -- does some substantial rewriting in some cases.
3801 -- We need a predicate check if the type has predicates, and if either
3802 -- there is an initializing expression, or for default initialization
3803 -- when we have at least one case of an explicit default initial value
3804 -- and then this is not an internal declaration whose initialization
3805 -- comes later (as for an aggregate expansion).
3807 if not Suppress_Assignment_Checks (N)
3808 and then Present (Predicate_Function (T))
3809 and then not No_Initialization (N)
3813 Is_Partially_Initialized_Type (T, Include_Implicit => False))
3815 -- If the type has a static predicate and the expression is known at
3816 -- compile time, see if the expression satisfies the predicate.
3819 Check_Expression_Against_Static_Predicate (E, T);
3823 Make_Predicate_Check (T, New_Occurrence_Of (Id, Loc)));
3826 -- Case of unconstrained type
3828 if Is_Indefinite_Subtype (T) then
3830 -- In SPARK, a declaration of unconstrained type is allowed
3831 -- only for constants of type string.
3833 if Is_String_Type (T) and then not Constant_Present (N) then
3834 Check_SPARK_05_Restriction
3835 ("declaration of object of unconstrained type not allowed", N);
3838 -- Nothing to do in deferred constant case
3840 if Constant_Present (N) and then No (E) then
3843 -- Case of no initialization present
3846 if No_Initialization (N) then
3849 elsif Is_Class_Wide_Type (T) then
3851 ("initialization required in class-wide declaration ", N);
3855 ("unconstrained subtype not allowed (need initialization)",
3856 Object_Definition (N));
3858 if Is_Record_Type (T) and then Has_Discriminants (T) then
3860 ("\provide initial value or explicit discriminant values",
3861 Object_Definition (N));
3864 ("\or give default discriminant values for type&",
3865 Object_Definition (N), T);
3867 elsif Is_Array_Type (T) then
3869 ("\provide initial value or explicit array bounds",
3870 Object_Definition (N));
3874 -- Case of initialization present but in error. Set initial
3875 -- expression as absent (but do not make above complaints)
3877 elsif E = Error then
3878 Set_Expression (N, Empty);
3881 -- Case of initialization present
3884 -- Check restrictions in Ada 83
3886 if not Constant_Present (N) then
3888 -- Unconstrained variables not allowed in Ada 83 mode
3890 if Ada_Version = Ada_83
3891 and then Comes_From_Source (Object_Definition (N))
3894 ("(Ada 83) unconstrained variable not allowed",
3895 Object_Definition (N));
3899 -- Now we constrain the variable from the initializing expression
3901 -- If the expression is an aggregate, it has been expanded into
3902 -- individual assignments. Retrieve the actual type from the
3903 -- expanded construct.
3905 if Is_Array_Type (T)
3906 and then No_Initialization (N)
3907 and then Nkind (Original_Node (E)) = N_Aggregate
3911 -- In case of class-wide interface object declarations we delay
3912 -- the generation of the equivalent record type declarations until
3913 -- its expansion because there are cases in they are not required.
3915 elsif Is_Interface (T) then
3918 -- In GNATprove mode, Expand_Subtype_From_Expr does nothing. Thus,
3919 -- we should prevent the generation of another Itype with the
3920 -- same name as the one already generated, or we end up with
3921 -- two identical types in GNATprove.
3923 elsif GNATprove_Mode then
3926 -- If the type is an unchecked union, no subtype can be built from
3927 -- the expression. Rewrite declaration as a renaming, which the
3928 -- back-end can handle properly. This is a rather unusual case,
3929 -- because most unchecked_union declarations have default values
3930 -- for discriminants and are thus not indefinite.
3932 elsif Is_Unchecked_Union (T) then
3933 if Constant_Present (N) or else Nkind (E) = N_Function_Call then
3934 Set_Ekind (Id, E_Constant);
3936 Set_Ekind (Id, E_Variable);
3939 -- An object declared within a Ghost region is automatically
3940 -- Ghost (SPARK RM 6.9(2)).
3942 if Comes_From_Source (Id) and then Ghost_Mode > None then
3943 Set_Is_Ghost_Entity (Id);
3945 -- The Ghost policy in effect at the point of declaration
3946 -- and at the point of completion must match
3947 -- (SPARK RM 6.9(15)).
3949 if Present (Prev_Entity)
3950 and then Is_Ghost_Entity (Prev_Entity)
3952 Check_Ghost_Completion (Prev_Entity, Id);
3957 Make_Object_Renaming_Declaration (Loc,
3958 Defining_Identifier => Id,
3959 Subtype_Mark => New_Occurrence_Of (T, Loc),
3962 Set_Renamed_Object (Id, E);
3963 Freeze_Before (N, T);
3968 Expand_Subtype_From_Expr (N, T, Object_Definition (N), E);
3969 Act_T := Find_Type_Of_Object (Object_Definition (N), N);
3972 Set_Is_Constr_Subt_For_U_Nominal (Act_T);
3974 if Aliased_Present (N) then
3975 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
3978 Freeze_Before (N, Act_T);
3979 Freeze_Before (N, T);
3982 elsif Is_Array_Type (T)
3983 and then No_Initialization (N)
3984 and then Nkind (Original_Node (E)) = N_Aggregate
3986 if not Is_Entity_Name (Object_Definition (N)) then
3988 Check_Compile_Time_Size (Act_T);
3990 if Aliased_Present (N) then
3991 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
3995 -- When the given object definition and the aggregate are specified
3996 -- independently, and their lengths might differ do a length check.
3997 -- This cannot happen if the aggregate is of the form (others =>...)
3999 if not Is_Constrained (T) then
4002 elsif Nkind (E) = N_Raise_Constraint_Error then
4004 -- Aggregate is statically illegal. Place back in declaration
4006 Set_Expression (N, E);
4007 Set_No_Initialization (N, False);
4009 elsif T = Etype (E) then
4012 elsif Nkind (E) = N_Aggregate
4013 and then Present (Component_Associations (E))
4014 and then Present (Choices (First (Component_Associations (E))))
4015 and then Nkind (First
4016 (Choices (First (Component_Associations (E))))) = N_Others_Choice
4021 Apply_Length_Check (E, T);
4024 -- If the type is limited unconstrained with defaulted discriminants and
4025 -- there is no expression, then the object is constrained by the
4026 -- defaults, so it is worthwhile building the corresponding subtype.
4028 elsif (Is_Limited_Record (T) or else Is_Concurrent_Type (T))
4029 and then not Is_Constrained (T)
4030 and then Has_Discriminants (T)
4033 Act_T := Build_Default_Subtype (T, N);
4035 -- Ada 2005: A limited object may be initialized by means of an
4036 -- aggregate. If the type has default discriminants it has an
4037 -- unconstrained nominal type, Its actual subtype will be obtained
4038 -- from the aggregate, and not from the default discriminants.
4043 Rewrite (Object_Definition (N), New_Occurrence_Of (Act_T, Loc));
4045 elsif Nkind (E) = N_Function_Call
4046 and then Constant_Present (N)
4047 and then Has_Unconstrained_Elements (Etype (E))
4049 -- The back-end has problems with constants of a discriminated type
4050 -- with defaults, if the initial value is a function call. We
4051 -- generate an intermediate temporary that will receive a reference
4052 -- to the result of the call. The initialization expression then
4053 -- becomes a dereference of that temporary.
4055 Remove_Side_Effects (E);
4057 -- If this is a constant declaration of an unconstrained type and
4058 -- the initialization is an aggregate, we can use the subtype of the
4059 -- aggregate for the declared entity because it is immutable.
4061 elsif not Is_Constrained (T)
4062 and then Has_Discriminants (T)
4063 and then Constant_Present (N)
4064 and then not Has_Unchecked_Union (T)
4065 and then Nkind (E) = N_Aggregate
4070 -- Check No_Wide_Characters restriction
4072 Check_Wide_Character_Restriction (T, Object_Definition (N));
4074 -- Indicate this is not set in source. Certainly true for constants, and
4075 -- true for variables so far (will be reset for a variable if and when
4076 -- we encounter a modification in the source).
4078 Set_Never_Set_In_Source (Id);
4080 -- Now establish the proper kind and type of the object
4082 if Constant_Present (N) then
4083 Set_Ekind (Id, E_Constant);
4084 Set_Is_True_Constant (Id);
4087 Set_Ekind (Id, E_Variable);
4089 -- A variable is set as shared passive if it appears in a shared
4090 -- passive package, and is at the outer level. This is not done for
4091 -- entities generated during expansion, because those are always
4092 -- manipulated locally.
4094 if Is_Shared_Passive (Current_Scope)
4095 and then Is_Library_Level_Entity (Id)
4096 and then Comes_From_Source (Id)
4098 Set_Is_Shared_Passive (Id);
4099 Check_Shared_Var (Id, T, N);
4102 -- Set Has_Initial_Value if initializing expression present. Note
4103 -- that if there is no initializing expression, we leave the state
4104 -- of this flag unchanged (usually it will be False, but notably in
4105 -- the case of exception choice variables, it will already be true).
4108 Set_Has_Initial_Value (Id);
4111 Set_Contract (Id, Make_Contract (Sloc (Id)));
4114 -- Initialize alignment and size and capture alignment setting
4116 Init_Alignment (Id);
4118 Set_Optimize_Alignment_Flags (Id);
4120 -- An object declared within a Ghost region is automatically Ghost
4121 -- (SPARK RM 6.9(2)).
4123 if Comes_From_Source (Id)
4124 and then (Ghost_Mode > None
4125 or else (Present (Prev_Entity)
4126 and then Is_Ghost_Entity (Prev_Entity)))
4128 Set_Is_Ghost_Entity (Id);
4130 -- The Ghost policy in effect at the point of declaration and at the
4131 -- point of completion must match (SPARK RM 6.9(16)).
4133 if Present (Prev_Entity) and then Is_Ghost_Entity (Prev_Entity) then
4134 Check_Ghost_Completion (Prev_Entity, Id);
4138 -- Deal with aliased case
4140 if Aliased_Present (N) then
4141 Set_Is_Aliased (Id);
4143 -- If the object is aliased and the type is unconstrained with
4144 -- defaulted discriminants and there is no expression, then the
4145 -- object is constrained by the defaults, so it is worthwhile
4146 -- building the corresponding subtype.
4148 -- Ada 2005 (AI-363): If the aliased object is discriminated and
4149 -- unconstrained, then only establish an actual subtype if the
4150 -- nominal subtype is indefinite. In definite cases the object is
4151 -- unconstrained in Ada 2005.
4154 and then Is_Record_Type (T)
4155 and then not Is_Constrained (T)
4156 and then Has_Discriminants (T)
4157 and then (Ada_Version < Ada_2005 or else Is_Indefinite_Subtype (T))
4159 Set_Actual_Subtype (Id, Build_Default_Subtype (T, N));
4163 -- Now we can set the type of the object
4165 Set_Etype (Id, Act_T);
4167 -- Non-constant object is marked to be treated as volatile if type is
4168 -- volatile and we clear the Current_Value setting that may have been
4169 -- set above. Doing so for constants isn't required and might interfere
4170 -- with possible uses of the object as a static expression in contexts
4171 -- incompatible with volatility (e.g. as a case-statement alternative).
4173 if Ekind (Id) /= E_Constant and then Treat_As_Volatile (Etype (Id)) then
4174 Set_Treat_As_Volatile (Id);
4175 Set_Current_Value (Id, Empty);
4178 -- Deal with controlled types
4180 if Has_Controlled_Component (Etype (Id))
4181 or else Is_Controlled (Etype (Id))
4183 if not Is_Library_Level_Entity (Id) then
4184 Check_Restriction (No_Nested_Finalization, N);
4186 Validate_Controlled_Object (Id);
4190 if Has_Task (Etype (Id)) then
4191 Check_Restriction (No_Tasking, N);
4193 -- Deal with counting max tasks
4195 -- Nothing to do if inside a generic
4197 if Inside_A_Generic then
4200 -- If library level entity, then count tasks
4202 elsif Is_Library_Level_Entity (Id) then
4203 Check_Restriction (Max_Tasks, N, Count_Tasks (Etype (Id)));
4205 -- If not library level entity, then indicate we don't know max
4206 -- tasks and also check task hierarchy restriction and blocking
4207 -- operation (since starting a task is definitely blocking).
4210 Check_Restriction (Max_Tasks, N);
4211 Check_Restriction (No_Task_Hierarchy, N);
4212 Check_Potentially_Blocking_Operation (N);
4215 -- A rather specialized test. If we see two tasks being declared
4216 -- of the same type in the same object declaration, and the task
4217 -- has an entry with an address clause, we know that program error
4218 -- will be raised at run time since we can't have two tasks with
4219 -- entries at the same address.
4221 if Is_Task_Type (Etype (Id)) and then More_Ids (N) then
4226 E := First_Entity (Etype (Id));
4227 while Present (E) loop
4228 if Ekind (E) = E_Entry
4229 and then Present (Get_Attribute_Definition_Clause
4230 (E, Attribute_Address))
4232 Error_Msg_Warn := SPARK_Mode /= On;
4234 ("more than one task with same entry address<<", N);
4235 Error_Msg_N ("\Program_Error [<<", N);
4237 Make_Raise_Program_Error (Loc,
4238 Reason => PE_Duplicated_Entry_Address));
4248 -- Some simple constant-propagation: if the expression is a constant
4249 -- string initialized with a literal, share the literal. This avoids
4253 and then Is_Entity_Name (E)
4254 and then Ekind (Entity (E)) = E_Constant
4255 and then Base_Type (Etype (E)) = Standard_String
4258 Val : constant Node_Id := Constant_Value (Entity (E));
4260 if Present (Val) and then Nkind (Val) = N_String_Literal then
4261 Rewrite (E, New_Copy (Val));
4266 -- Another optimization: if the nominal subtype is unconstrained and
4267 -- the expression is a function call that returns an unconstrained
4268 -- type, rewrite the declaration as a renaming of the result of the
4269 -- call. The exceptions below are cases where the copy is expected,
4270 -- either by the back end (Aliased case) or by the semantics, as for
4271 -- initializing controlled types or copying tags for classwide types.
4274 and then Nkind (E) = N_Explicit_Dereference
4275 and then Nkind (Original_Node (E)) = N_Function_Call
4276 and then not Is_Library_Level_Entity (Id)
4277 and then not Is_Constrained (Underlying_Type (T))
4278 and then not Is_Aliased (Id)
4279 and then not Is_Class_Wide_Type (T)
4280 and then not Is_Controlled (T)
4281 and then not Has_Controlled_Component (Base_Type (T))
4282 and then Expander_Active
4285 Make_Object_Renaming_Declaration (Loc,
4286 Defining_Identifier => Id,
4287 Access_Definition => Empty,
4288 Subtype_Mark => New_Occurrence_Of
4289 (Base_Type (Etype (Id)), Loc),
4292 Set_Renamed_Object (Id, E);
4294 -- Force generation of debugging information for the constant and for
4295 -- the renamed function call.
4297 Set_Debug_Info_Needed (Id);
4298 Set_Debug_Info_Needed (Entity (Prefix (E)));
4301 if Present (Prev_Entity)
4302 and then Is_Frozen (Prev_Entity)
4303 and then not Error_Posted (Id)
4305 Error_Msg_N ("full constant declaration appears too late", N);
4308 Check_Eliminated (Id);
4310 -- Deal with setting In_Private_Part flag if in private part
4312 if Ekind (Scope (Id)) = E_Package and then In_Private_Part (Scope (Id))
4314 Set_In_Private_Part (Id);
4317 -- Check for violation of No_Local_Timing_Events
4319 if Restriction_Check_Required (No_Local_Timing_Events)
4320 and then not Is_Library_Level_Entity (Id)
4321 and then Is_RTE (Etype (Id), RE_Timing_Event)
4323 Check_Restriction (No_Local_Timing_Events, N);
4327 -- Initialize the refined state of a variable here because this is a
4328 -- common destination for legal and illegal object declarations.
4330 if Ekind (Id) = E_Variable then
4331 Set_Encapsulating_State (Id, Empty);
4334 if Has_Aspects (N) then
4335 Analyze_Aspect_Specifications (N, Id);
4338 Analyze_Dimension (N);
4340 -- Verify whether the object declaration introduces an illegal hidden
4341 -- state within a package subject to a null abstract state.
4343 if Ekind (Id) = E_Variable then
4344 Check_No_Hidden_State (Id);
4346 end Analyze_Object_Declaration;
4348 ---------------------------
4349 -- Analyze_Others_Choice --
4350 ---------------------------
4352 -- Nothing to do for the others choice node itself, the semantic analysis
4353 -- of the others choice will occur as part of the processing of the parent
4355 procedure Analyze_Others_Choice (N : Node_Id) is
4356 pragma Warnings (Off, N);
4359 end Analyze_Others_Choice;
4361 -------------------------------------------
4362 -- Analyze_Private_Extension_Declaration --
4363 -------------------------------------------
4365 procedure Analyze_Private_Extension_Declaration (N : Node_Id) is
4366 T : constant Entity_Id := Defining_Identifier (N);
4367 Indic : constant Node_Id := Subtype_Indication (N);
4368 Parent_Type : Entity_Id;
4369 Parent_Base : Entity_Id;
4372 -- The private extension declaration may be subject to pragma Ghost with
4373 -- policy Ignore. Set the mode now to ensure that any nodes generated
4374 -- during analysis and expansion are properly flagged as ignored Ghost.
4378 -- Ada 2005 (AI-251): Decorate all names in list of ancestor interfaces
4380 if Is_Non_Empty_List (Interface_List (N)) then
4386 Intf := First (Interface_List (N));
4387 while Present (Intf) loop
4388 T := Find_Type_Of_Subtype_Indic (Intf);
4390 Diagnose_Interface (Intf, T);
4396 Generate_Definition (T);
4398 -- For other than Ada 2012, just enter the name in the current scope
4400 if Ada_Version < Ada_2012 then
4403 -- Ada 2012 (AI05-0162): Enter the name in the current scope handling
4404 -- case of private type that completes an incomplete type.
4411 Prev := Find_Type_Name (N);
4413 pragma Assert (Prev = T
4414 or else (Ekind (Prev) = E_Incomplete_Type
4415 and then Present (Full_View (Prev))
4416 and then Full_View (Prev) = T));
4420 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
4421 Parent_Base := Base_Type (Parent_Type);
4423 if Parent_Type = Any_Type or else Etype (Parent_Type) = Any_Type then
4424 Set_Ekind (T, Ekind (Parent_Type));
4425 Set_Etype (T, Any_Type);
4428 elsif not Is_Tagged_Type (Parent_Type) then
4430 ("parent of type extension must be a tagged type ", Indic);
4433 elsif Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
4434 Error_Msg_N ("premature derivation of incomplete type", Indic);
4437 elsif Is_Concurrent_Type (Parent_Type) then
4439 ("parent type of a private extension cannot be "
4440 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
4442 Set_Etype (T, Any_Type);
4443 Set_Ekind (T, E_Limited_Private_Type);
4444 Set_Private_Dependents (T, New_Elmt_List);
4445 Set_Error_Posted (T);
4449 -- Perhaps the parent type should be changed to the class-wide type's
4450 -- specific type in this case to prevent cascading errors ???
4452 if Is_Class_Wide_Type (Parent_Type) then
4454 ("parent of type extension must not be a class-wide type", Indic);
4458 if (not Is_Package_Or_Generic_Package (Current_Scope)
4459 and then Nkind (Parent (N)) /= N_Generic_Subprogram_Declaration)
4460 or else In_Private_Part (Current_Scope)
4463 Error_Msg_N ("invalid context for private extension", N);
4466 -- Set common attributes
4468 Set_Is_Pure (T, Is_Pure (Current_Scope));
4469 Set_Scope (T, Current_Scope);
4470 Set_Ekind (T, E_Record_Type_With_Private);
4471 Init_Size_Align (T);
4472 Set_Default_SSO (T);
4474 Set_Etype (T, Parent_Base);
4475 Set_Has_Task (T, Has_Task (Parent_Base));
4476 Set_Has_Protected (T, Has_Task (Parent_Base));
4478 Set_Convention (T, Convention (Parent_Type));
4479 Set_First_Rep_Item (T, First_Rep_Item (Parent_Type));
4480 Set_Is_First_Subtype (T);
4481 Make_Class_Wide_Type (T);
4483 if Unknown_Discriminants_Present (N) then
4484 Set_Discriminant_Constraint (T, No_Elist);
4487 Build_Derived_Record_Type (N, Parent_Type, T);
4489 -- Propagate inherited invariant information. The new type has
4490 -- invariants, if the parent type has inheritable invariants,
4491 -- and these invariants can in turn be inherited.
4493 if Has_Inheritable_Invariants (Parent_Type) then
4494 Set_Has_Inheritable_Invariants (T);
4495 Set_Has_Invariants (T);
4498 -- Ada 2005 (AI-443): Synchronized private extension or a rewritten
4499 -- synchronized formal derived type.
4501 if Ada_Version >= Ada_2005 and then Synchronized_Present (N) then
4502 Set_Is_Limited_Record (T);
4504 -- Formal derived type case
4506 if Is_Generic_Type (T) then
4508 -- The parent must be a tagged limited type or a synchronized
4511 if (not Is_Tagged_Type (Parent_Type)
4512 or else not Is_Limited_Type (Parent_Type))
4514 (not Is_Interface (Parent_Type)
4515 or else not Is_Synchronized_Interface (Parent_Type))
4517 Error_Msg_NE ("parent type of & must be tagged limited " &
4518 "or synchronized", N, T);
4521 -- The progenitors (if any) must be limited or synchronized
4524 if Present (Interfaces (T)) then
4527 Iface_Elmt : Elmt_Id;
4530 Iface_Elmt := First_Elmt (Interfaces (T));
4531 while Present (Iface_Elmt) loop
4532 Iface := Node (Iface_Elmt);
4534 if not Is_Limited_Interface (Iface)
4535 and then not Is_Synchronized_Interface (Iface)
4537 Error_Msg_NE ("progenitor & must be limited " &
4538 "or synchronized", N, Iface);
4541 Next_Elmt (Iface_Elmt);
4546 -- Regular derived extension, the parent must be a limited or
4547 -- synchronized interface.
4550 if not Is_Interface (Parent_Type)
4551 or else (not Is_Limited_Interface (Parent_Type)
4552 and then not Is_Synchronized_Interface (Parent_Type))
4555 ("parent type of & must be limited interface", N, T);
4559 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
4560 -- extension with a synchronized parent must be explicitly declared
4561 -- synchronized, because the full view will be a synchronized type.
4562 -- This must be checked before the check for limited types below,
4563 -- to ensure that types declared limited are not allowed to extend
4564 -- synchronized interfaces.
4566 elsif Is_Interface (Parent_Type)
4567 and then Is_Synchronized_Interface (Parent_Type)
4568 and then not Synchronized_Present (N)
4571 ("private extension of& must be explicitly synchronized",
4574 elsif Limited_Present (N) then
4575 Set_Is_Limited_Record (T);
4577 if not Is_Limited_Type (Parent_Type)
4579 (not Is_Interface (Parent_Type)
4580 or else not Is_Limited_Interface (Parent_Type))
4582 Error_Msg_NE ("parent type& of limited extension must be limited",
4588 if Has_Aspects (N) then
4589 Analyze_Aspect_Specifications (N, T);
4591 end Analyze_Private_Extension_Declaration;
4593 ---------------------------------
4594 -- Analyze_Subtype_Declaration --
4595 ---------------------------------
4597 procedure Analyze_Subtype_Declaration
4599 Skip : Boolean := False)
4601 Id : constant Entity_Id := Defining_Identifier (N);
4603 R_Checks : Check_Result;
4606 -- The subtype declaration may be subject to pragma Ghost with policy
4607 -- Ignore. Set the mode now to ensure that any nodes generated during
4608 -- analysis and expansion are properly flagged as ignored Ghost.
4612 Generate_Definition (Id);
4613 Set_Is_Pure (Id, Is_Pure (Current_Scope));
4614 Init_Size_Align (Id);
4616 -- The following guard condition on Enter_Name is to handle cases where
4617 -- the defining identifier has already been entered into the scope but
4618 -- the declaration as a whole needs to be analyzed.
4620 -- This case in particular happens for derived enumeration types. The
4621 -- derived enumeration type is processed as an inserted enumeration type
4622 -- declaration followed by a rewritten subtype declaration. The defining
4623 -- identifier, however, is entered into the name scope very early in the
4624 -- processing of the original type declaration and therefore needs to be
4625 -- avoided here, when the created subtype declaration is analyzed. (See
4626 -- Build_Derived_Types)
4628 -- This also happens when the full view of a private type is derived
4629 -- type with constraints. In this case the entity has been introduced
4630 -- in the private declaration.
4632 -- Finally this happens in some complex cases when validity checks are
4633 -- enabled, where the same subtype declaration may be analyzed twice.
4634 -- This can happen if the subtype is created by the pre-analysis of
4635 -- an attribute tht gives the range of a loop statement, and the loop
4636 -- itself appears within an if_statement that will be rewritten during
4640 or else (Present (Etype (Id))
4641 and then (Is_Private_Type (Etype (Id))
4642 or else Is_Task_Type (Etype (Id))
4643 or else Is_Rewrite_Substitution (N)))
4647 elsif Current_Entity (Id) = Id then
4654 T := Process_Subtype (Subtype_Indication (N), N, Id, 'P');
4656 -- Class-wide equivalent types of records with unknown discriminants
4657 -- involve the generation of an itype which serves as the private view
4658 -- of a constrained record subtype. In such cases the base type of the
4659 -- current subtype we are processing is the private itype. Use the full
4660 -- of the private itype when decorating various attributes.
4663 and then Is_Private_Type (T)
4664 and then Present (Full_View (T))
4669 -- Inherit common attributes
4671 Set_Is_Volatile (Id, Is_Volatile (T));
4672 Set_Treat_As_Volatile (Id, Treat_As_Volatile (T));
4673 Set_Is_Generic_Type (Id, Is_Generic_Type (Base_Type (T)));
4674 Set_Convention (Id, Convention (T));
4676 -- If ancestor has predicates then so does the subtype, and in addition
4677 -- we must delay the freeze to properly arrange predicate inheritance.
4679 -- The Ancestor_Type test is really unpleasant, there seem to be cases
4680 -- in which T = ID, so the above tests and assignments do nothing???
4682 if Has_Predicates (T)
4683 or else (Present (Ancestor_Subtype (T))
4684 and then Has_Predicates (Ancestor_Subtype (T)))
4686 Set_Has_Predicates (Id);
4687 Set_Has_Delayed_Freeze (Id);
4690 -- Subtype of Boolean cannot have a constraint in SPARK
4692 if Is_Boolean_Type (T)
4693 and then Nkind (Subtype_Indication (N)) = N_Subtype_Indication
4695 Check_SPARK_05_Restriction
4696 ("subtype of Boolean cannot have constraint", N);
4699 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4701 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
4707 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint then
4708 One_Cstr := First (Constraints (Cstr));
4709 while Present (One_Cstr) loop
4711 -- Index or discriminant constraint in SPARK must be a
4715 Nkind_In (One_Cstr, N_Identifier, N_Expanded_Name)
4717 Check_SPARK_05_Restriction
4718 ("subtype mark required", One_Cstr);
4720 -- String subtype must have a lower bound of 1 in SPARK.
4721 -- Note that we do not need to test for the non-static case
4722 -- here, since that was already taken care of in
4723 -- Process_Range_Expr_In_Decl.
4725 elsif Base_Type (T) = Standard_String then
4726 Get_Index_Bounds (One_Cstr, Low, High);
4728 if Is_OK_Static_Expression (Low)
4729 and then Expr_Value (Low) /= 1
4731 Check_SPARK_05_Restriction
4732 ("String subtype must have lower bound of 1", N);
4742 -- In the case where there is no constraint given in the subtype
4743 -- indication, Process_Subtype just returns the Subtype_Mark, so its
4744 -- semantic attributes must be established here.
4746 if Nkind (Subtype_Indication (N)) /= N_Subtype_Indication then
4747 Set_Etype (Id, Base_Type (T));
4749 -- Subtype of unconstrained array without constraint is not allowed
4752 if Is_Array_Type (T) and then not Is_Constrained (T) then
4753 Check_SPARK_05_Restriction
4754 ("subtype of unconstrained array must have constraint", N);
4759 Set_Ekind (Id, E_Array_Subtype);
4760 Copy_Array_Subtype_Attributes (Id, T);
4762 when Decimal_Fixed_Point_Kind =>
4763 Set_Ekind (Id, E_Decimal_Fixed_Point_Subtype);
4764 Set_Digits_Value (Id, Digits_Value (T));
4765 Set_Delta_Value (Id, Delta_Value (T));
4766 Set_Scale_Value (Id, Scale_Value (T));
4767 Set_Small_Value (Id, Small_Value (T));
4768 Set_Scalar_Range (Id, Scalar_Range (T));
4769 Set_Machine_Radix_10 (Id, Machine_Radix_10 (T));
4770 Set_Is_Constrained (Id, Is_Constrained (T));
4771 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4772 Set_RM_Size (Id, RM_Size (T));
4774 when Enumeration_Kind =>
4775 Set_Ekind (Id, E_Enumeration_Subtype);
4776 Set_First_Literal (Id, First_Literal (Base_Type (T)));
4777 Set_Scalar_Range (Id, Scalar_Range (T));
4778 Set_Is_Character_Type (Id, Is_Character_Type (T));
4779 Set_Is_Constrained (Id, Is_Constrained (T));
4780 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4781 Set_RM_Size (Id, RM_Size (T));
4782 Inherit_Predicate_Flags (Id, T);
4784 when Ordinary_Fixed_Point_Kind =>
4785 Set_Ekind (Id, E_Ordinary_Fixed_Point_Subtype);
4786 Set_Scalar_Range (Id, Scalar_Range (T));
4787 Set_Small_Value (Id, Small_Value (T));
4788 Set_Delta_Value (Id, Delta_Value (T));
4789 Set_Is_Constrained (Id, Is_Constrained (T));
4790 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4791 Set_RM_Size (Id, RM_Size (T));
4794 Set_Ekind (Id, E_Floating_Point_Subtype);
4795 Set_Scalar_Range (Id, Scalar_Range (T));
4796 Set_Digits_Value (Id, Digits_Value (T));
4797 Set_Is_Constrained (Id, Is_Constrained (T));
4799 when Signed_Integer_Kind =>
4800 Set_Ekind (Id, E_Signed_Integer_Subtype);
4801 Set_Scalar_Range (Id, Scalar_Range (T));
4802 Set_Is_Constrained (Id, Is_Constrained (T));
4803 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4804 Set_RM_Size (Id, RM_Size (T));
4805 Inherit_Predicate_Flags (Id, T);
4807 when Modular_Integer_Kind =>
4808 Set_Ekind (Id, E_Modular_Integer_Subtype);
4809 Set_Scalar_Range (Id, Scalar_Range (T));
4810 Set_Is_Constrained (Id, Is_Constrained (T));
4811 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4812 Set_RM_Size (Id, RM_Size (T));
4813 Inherit_Predicate_Flags (Id, T);
4815 when Class_Wide_Kind =>
4816 Set_Ekind (Id, E_Class_Wide_Subtype);
4817 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4818 Set_Cloned_Subtype (Id, T);
4819 Set_Is_Tagged_Type (Id, True);
4820 Set_Has_Unknown_Discriminants
4822 Set_No_Tagged_Streams_Pragma
4823 (Id, No_Tagged_Streams_Pragma (T));
4825 if Ekind (T) = E_Class_Wide_Subtype then
4826 Set_Equivalent_Type (Id, Equivalent_Type (T));
4829 when E_Record_Type | E_Record_Subtype =>
4830 Set_Ekind (Id, E_Record_Subtype);
4832 if Ekind (T) = E_Record_Subtype
4833 and then Present (Cloned_Subtype (T))
4835 Set_Cloned_Subtype (Id, Cloned_Subtype (T));
4837 Set_Cloned_Subtype (Id, T);
4840 Set_First_Entity (Id, First_Entity (T));
4841 Set_Last_Entity (Id, Last_Entity (T));
4842 Set_Has_Discriminants (Id, Has_Discriminants (T));
4843 Set_Is_Constrained (Id, Is_Constrained (T));
4844 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4845 Set_Has_Implicit_Dereference
4846 (Id, Has_Implicit_Dereference (T));
4847 Set_Has_Unknown_Discriminants
4848 (Id, Has_Unknown_Discriminants (T));
4850 if Has_Discriminants (T) then
4851 Set_Discriminant_Constraint
4852 (Id, Discriminant_Constraint (T));
4853 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4855 elsif Has_Unknown_Discriminants (Id) then
4856 Set_Discriminant_Constraint (Id, No_Elist);
4859 if Is_Tagged_Type (T) then
4860 Set_Is_Tagged_Type (Id, True);
4861 Set_No_Tagged_Streams_Pragma
4862 (Id, No_Tagged_Streams_Pragma (T));
4863 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4864 Set_Direct_Primitive_Operations
4865 (Id, Direct_Primitive_Operations (T));
4866 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4868 if Is_Interface (T) then
4869 Set_Is_Interface (Id);
4870 Set_Is_Limited_Interface (Id, Is_Limited_Interface (T));
4874 when Private_Kind =>
4875 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4876 Set_Has_Discriminants (Id, Has_Discriminants (T));
4877 Set_Is_Constrained (Id, Is_Constrained (T));
4878 Set_First_Entity (Id, First_Entity (T));
4879 Set_Last_Entity (Id, Last_Entity (T));
4880 Set_Private_Dependents (Id, New_Elmt_List);
4881 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4882 Set_Has_Implicit_Dereference
4883 (Id, Has_Implicit_Dereference (T));
4884 Set_Has_Unknown_Discriminants
4885 (Id, Has_Unknown_Discriminants (T));
4886 Set_Known_To_Have_Preelab_Init
4887 (Id, Known_To_Have_Preelab_Init (T));
4889 if Is_Tagged_Type (T) then
4890 Set_Is_Tagged_Type (Id);
4891 Set_No_Tagged_Streams_Pragma (Id,
4892 No_Tagged_Streams_Pragma (T));
4893 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4894 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4895 Set_Direct_Primitive_Operations (Id,
4896 Direct_Primitive_Operations (T));
4899 -- In general the attributes of the subtype of a private type
4900 -- are the attributes of the partial view of parent. However,
4901 -- the full view may be a discriminated type, and the subtype
4902 -- must share the discriminant constraint to generate correct
4903 -- calls to initialization procedures.
4905 if Has_Discriminants (T) then
4906 Set_Discriminant_Constraint
4907 (Id, Discriminant_Constraint (T));
4908 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4910 elsif Present (Full_View (T))
4911 and then Has_Discriminants (Full_View (T))
4913 Set_Discriminant_Constraint
4914 (Id, Discriminant_Constraint (Full_View (T)));
4915 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4917 -- This would seem semantically correct, but apparently
4918 -- generates spurious errors about missing components ???
4920 -- Set_Has_Discriminants (Id);
4923 Prepare_Private_Subtype_Completion (Id, N);
4925 -- If this is the subtype of a constrained private type with
4926 -- discriminants that has got a full view and we also have
4927 -- built a completion just above, show that the completion
4928 -- is a clone of the full view to the back-end.
4930 if Has_Discriminants (T)
4931 and then not Has_Unknown_Discriminants (T)
4932 and then not Is_Empty_Elmt_List (Discriminant_Constraint (T))
4933 and then Present (Full_View (T))
4934 and then Present (Full_View (Id))
4936 Set_Cloned_Subtype (Full_View (Id), Full_View (T));
4940 Set_Ekind (Id, E_Access_Subtype);
4941 Set_Is_Constrained (Id, Is_Constrained (T));
4942 Set_Is_Access_Constant
4943 (Id, Is_Access_Constant (T));
4944 Set_Directly_Designated_Type
4945 (Id, Designated_Type (T));
4946 Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T));
4948 -- A Pure library_item must not contain the declaration of a
4949 -- named access type, except within a subprogram, generic
4950 -- subprogram, task unit, or protected unit, or if it has
4951 -- a specified Storage_Size of zero (RM05-10.2.1(15.4-15.5)).
4953 if Comes_From_Source (Id)
4954 and then In_Pure_Unit
4955 and then not In_Subprogram_Task_Protected_Unit
4956 and then not No_Pool_Assigned (Id)
4959 ("named access types not allowed in pure unit", N);
4962 when Concurrent_Kind =>
4963 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4964 Set_Corresponding_Record_Type (Id,
4965 Corresponding_Record_Type (T));
4966 Set_First_Entity (Id, First_Entity (T));
4967 Set_First_Private_Entity (Id, First_Private_Entity (T));
4968 Set_Has_Discriminants (Id, Has_Discriminants (T));
4969 Set_Is_Constrained (Id, Is_Constrained (T));
4970 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
4971 Set_Last_Entity (Id, Last_Entity (T));
4973 if Is_Tagged_Type (T) then
4974 Set_No_Tagged_Streams_Pragma
4975 (Id, No_Tagged_Streams_Pragma (T));
4978 if Has_Discriminants (T) then
4979 Set_Discriminant_Constraint (Id,
4980 Discriminant_Constraint (T));
4981 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4984 when E_Incomplete_Type =>
4985 if Ada_Version >= Ada_2005 then
4987 -- In Ada 2005 an incomplete type can be explicitly tagged:
4988 -- propagate indication.
4990 Set_Ekind (Id, E_Incomplete_Subtype);
4991 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
4992 Set_Private_Dependents (Id, New_Elmt_List);
4994 if Is_Tagged_Type (Id) then
4995 Set_No_Tagged_Streams_Pragma
4996 (Id, No_Tagged_Streams_Pragma (T));
4999 -- Ada 2005 (AI-412): Decorate an incomplete subtype of an
5000 -- incomplete type visible through a limited with clause.
5002 if From_Limited_With (T)
5003 and then Present (Non_Limited_View (T))
5005 Set_From_Limited_With (Id);
5006 Set_Non_Limited_View (Id, Non_Limited_View (T));
5008 -- Ada 2005 (AI-412): Add the regular incomplete subtype
5009 -- to the private dependents of the original incomplete
5010 -- type for future transformation.
5013 Append_Elmt (Id, Private_Dependents (T));
5016 -- If the subtype name denotes an incomplete type an error
5017 -- was already reported by Process_Subtype.
5020 Set_Etype (Id, Any_Type);
5024 raise Program_Error;
5028 if Etype (Id) = Any_Type then
5032 -- Some common processing on all types
5034 Set_Size_Info (Id, T);
5035 Set_First_Rep_Item (Id, First_Rep_Item (T));
5037 -- If the parent type is a generic actual, so is the subtype. This may
5038 -- happen in a nested instance. Why Comes_From_Source test???
5040 if not Comes_From_Source (N) then
5041 Set_Is_Generic_Actual_Type (Id, Is_Generic_Actual_Type (T));
5046 Set_Is_Immediately_Visible (Id, True);
5047 Set_Depends_On_Private (Id, Has_Private_Component (T));
5048 Set_Is_Descendent_Of_Address (Id, Is_Descendent_Of_Address (T));
5050 if Is_Interface (T) then
5051 Set_Is_Interface (Id);
5054 if Present (Generic_Parent_Type (N))
5056 (Nkind (Parent (Generic_Parent_Type (N))) /=
5057 N_Formal_Type_Declaration
5058 or else Nkind (Formal_Type_Definition
5059 (Parent (Generic_Parent_Type (N)))) /=
5060 N_Formal_Private_Type_Definition)
5062 if Is_Tagged_Type (Id) then
5064 -- If this is a generic actual subtype for a synchronized type,
5065 -- the primitive operations are those of the corresponding record
5066 -- for which there is a separate subtype declaration.
5068 if Is_Concurrent_Type (Id) then
5070 elsif Is_Class_Wide_Type (Id) then
5071 Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T));
5073 Derive_Subprograms (Generic_Parent_Type (N), Id, T);
5076 elsif Scope (Etype (Id)) /= Standard_Standard then
5077 Derive_Subprograms (Generic_Parent_Type (N), Id);
5081 if Is_Private_Type (T) and then Present (Full_View (T)) then
5082 Conditional_Delay (Id, Full_View (T));
5084 -- The subtypes of components or subcomponents of protected types
5085 -- do not need freeze nodes, which would otherwise appear in the
5086 -- wrong scope (before the freeze node for the protected type). The
5087 -- proper subtypes are those of the subcomponents of the corresponding
5090 elsif Ekind (Scope (Id)) /= E_Protected_Type
5091 and then Present (Scope (Scope (Id))) -- error defense
5092 and then Ekind (Scope (Scope (Id))) /= E_Protected_Type
5094 Conditional_Delay (Id, T);
5097 -- Check that Constraint_Error is raised for a scalar subtype indication
5098 -- when the lower or upper bound of a non-null range lies outside the
5099 -- range of the type mark.
5101 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5102 if Is_Scalar_Type (Etype (Id))
5103 and then Scalar_Range (Id) /=
5104 Scalar_Range (Etype (Subtype_Mark
5105 (Subtype_Indication (N))))
5109 Etype (Subtype_Mark (Subtype_Indication (N))));
5111 -- In the array case, check compatibility for each index
5113 elsif Is_Array_Type (Etype (Id)) and then Present (First_Index (Id))
5115 -- This really should be a subprogram that finds the indications
5119 Subt_Index : Node_Id := First_Index (Id);
5120 Target_Index : Node_Id :=
5122 (Subtype_Mark (Subtype_Indication (N))));
5123 Has_Dyn_Chk : Boolean := Has_Dynamic_Range_Check (N);
5126 while Present (Subt_Index) loop
5127 if ((Nkind (Subt_Index) = N_Identifier
5128 and then Ekind (Entity (Subt_Index)) in Scalar_Kind)
5129 or else Nkind (Subt_Index) = N_Subtype_Indication)
5131 Nkind (Scalar_Range (Etype (Subt_Index))) = N_Range
5134 Target_Typ : constant Entity_Id :=
5135 Etype (Target_Index);
5139 (Scalar_Range (Etype (Subt_Index)),
5142 Defining_Identifier (N));
5144 -- Reset Has_Dynamic_Range_Check on the subtype to
5145 -- prevent elision of the index check due to a dynamic
5146 -- check generated for a preceding index (needed since
5147 -- Insert_Range_Checks tries to avoid generating
5148 -- redundant checks on a given declaration).
5150 Set_Has_Dynamic_Range_Check (N, False);
5156 Sloc (Defining_Identifier (N)));
5158 -- Record whether this index involved a dynamic check
5161 Has_Dyn_Chk or else Has_Dynamic_Range_Check (N);
5165 Next_Index (Subt_Index);
5166 Next_Index (Target_Index);
5169 -- Finally, mark whether the subtype involves dynamic checks
5171 Set_Has_Dynamic_Range_Check (N, Has_Dyn_Chk);
5176 -- A type invariant applies to any subtype in its scope, in particular
5177 -- to a generic actual.
5179 if Has_Invariants (T) and then In_Open_Scopes (Scope (T)) then
5180 Set_Has_Invariants (Id);
5181 Set_Invariant_Procedure (Id, Invariant_Procedure (T));
5184 -- Make sure that generic actual types are properly frozen. The subtype
5185 -- is marked as a generic actual type when the enclosing instance is
5186 -- analyzed, so here we identify the subtype from the tree structure.
5189 and then Is_Generic_Actual_Type (Id)
5190 and then In_Instance
5191 and then not Comes_From_Source (N)
5192 and then Nkind (Subtype_Indication (N)) /= N_Subtype_Indication
5193 and then Is_Frozen (T)
5195 Freeze_Before (N, Id);
5198 Set_Optimize_Alignment_Flags (Id);
5199 Check_Eliminated (Id);
5202 if Has_Aspects (N) then
5203 Analyze_Aspect_Specifications (N, Id);
5206 Analyze_Dimension (N);
5207 end Analyze_Subtype_Declaration;
5209 --------------------------------
5210 -- Analyze_Subtype_Indication --
5211 --------------------------------
5213 procedure Analyze_Subtype_Indication (N : Node_Id) is
5214 T : constant Entity_Id := Subtype_Mark (N);
5215 R : constant Node_Id := Range_Expression (Constraint (N));
5222 Set_Etype (N, Etype (R));
5223 Resolve (R, Entity (T));
5225 Set_Error_Posted (R);
5226 Set_Error_Posted (T);
5228 end Analyze_Subtype_Indication;
5230 --------------------------
5231 -- Analyze_Variant_Part --
5232 --------------------------
5234 procedure Analyze_Variant_Part (N : Node_Id) is
5235 Discr_Name : Node_Id;
5236 Discr_Type : Entity_Id;
5238 procedure Process_Variant (A : Node_Id);
5239 -- Analyze declarations for a single variant
5241 package Analyze_Variant_Choices is
5242 new Generic_Analyze_Choices (Process_Variant);
5243 use Analyze_Variant_Choices;
5245 ---------------------
5246 -- Process_Variant --
5247 ---------------------
5249 procedure Process_Variant (A : Node_Id) is
5250 CL : constant Node_Id := Component_List (A);
5252 if not Null_Present (CL) then
5253 Analyze_Declarations (Component_Items (CL));
5255 if Present (Variant_Part (CL)) then
5256 Analyze (Variant_Part (CL));
5259 end Process_Variant;
5261 -- Start of processing for Analyze_Variant_Part
5264 Discr_Name := Name (N);
5265 Analyze (Discr_Name);
5267 -- If Discr_Name bad, get out (prevent cascaded errors)
5269 if Etype (Discr_Name) = Any_Type then
5273 -- Check invalid discriminant in variant part
5275 if Ekind (Entity (Discr_Name)) /= E_Discriminant then
5276 Error_Msg_N ("invalid discriminant name in variant part", Discr_Name);
5279 Discr_Type := Etype (Entity (Discr_Name));
5281 if not Is_Discrete_Type (Discr_Type) then
5283 ("discriminant in a variant part must be of a discrete type",
5288 -- Now analyze the choices, which also analyzes the declarations that
5289 -- are associated with each choice.
5291 Analyze_Choices (Variants (N), Discr_Type);
5293 -- Note: we used to instantiate and call Check_Choices here to check
5294 -- that the choices covered the discriminant, but it's too early to do
5295 -- that because of statically predicated subtypes, whose analysis may
5296 -- be deferred to their freeze point which may be as late as the freeze
5297 -- point of the containing record. So this call is now to be found in
5298 -- Freeze_Record_Declaration.
5300 end Analyze_Variant_Part;
5302 ----------------------------
5303 -- Array_Type_Declaration --
5304 ----------------------------
5306 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is
5307 Component_Def : constant Node_Id := Component_Definition (Def);
5308 Component_Typ : constant Node_Id := Subtype_Indication (Component_Def);
5309 Element_Type : Entity_Id;
5310 Implicit_Base : Entity_Id;
5312 Related_Id : Entity_Id := Empty;
5314 P : constant Node_Id := Parent (Def);
5318 if Nkind (Def) = N_Constrained_Array_Definition then
5319 Index := First (Discrete_Subtype_Definitions (Def));
5321 Index := First (Subtype_Marks (Def));
5324 -- Find proper names for the implicit types which may be public. In case
5325 -- of anonymous arrays we use the name of the first object of that type
5329 Related_Id := Defining_Identifier (P);
5335 while Present (Index) loop
5338 -- Test for odd case of trying to index a type by the type itself
5340 if Is_Entity_Name (Index) and then Entity (Index) = T then
5341 Error_Msg_N ("type& cannot be indexed by itself", Index);
5342 Set_Entity (Index, Standard_Boolean);
5343 Set_Etype (Index, Standard_Boolean);
5346 -- Check SPARK restriction requiring a subtype mark
5348 if not Nkind_In (Index, N_Identifier, N_Expanded_Name) then
5349 Check_SPARK_05_Restriction ("subtype mark required", Index);
5352 -- Add a subtype declaration for each index of private array type
5353 -- declaration whose etype is also private. For example:
5356 -- type Index is private;
5358 -- type Table is array (Index) of ...
5361 -- This is currently required by the expander for the internally
5362 -- generated equality subprogram of records with variant parts in
5363 -- which the etype of some component is such private type.
5365 if Ekind (Current_Scope) = E_Package
5366 and then In_Private_Part (Current_Scope)
5367 and then Has_Private_Declaration (Etype (Index))
5370 Loc : constant Source_Ptr := Sloc (Def);
5375 New_E := Make_Temporary (Loc, 'T');
5376 Set_Is_Internal (New_E);
5379 Make_Subtype_Declaration (Loc,
5380 Defining_Identifier => New_E,
5381 Subtype_Indication =>
5382 New_Occurrence_Of (Etype (Index), Loc));
5384 Insert_Before (Parent (Def), Decl);
5386 Set_Etype (Index, New_E);
5388 -- If the index is a range the Entity attribute is not
5389 -- available. Example:
5392 -- type T is private;
5394 -- type T is new Natural;
5395 -- Table : array (T(1) .. T(10)) of Boolean;
5398 if Nkind (Index) /= N_Range then
5399 Set_Entity (Index, New_E);
5404 Make_Index (Index, P, Related_Id, Nb_Index);
5406 -- Check error of subtype with predicate for index type
5408 Bad_Predicated_Subtype_Use
5409 ("subtype& has predicate, not allowed as index subtype",
5410 Index, Etype (Index));
5412 -- Move to next index
5415 Nb_Index := Nb_Index + 1;
5418 -- Process subtype indication if one is present
5420 if Present (Component_Typ) then
5421 Element_Type := Process_Subtype (Component_Typ, P, Related_Id, 'C');
5423 Set_Etype (Component_Typ, Element_Type);
5425 if not Nkind_In (Component_Typ, N_Identifier, N_Expanded_Name) then
5426 Check_SPARK_05_Restriction
5427 ("subtype mark required", Component_Typ);
5430 -- Ada 2005 (AI-230): Access Definition case
5432 else pragma Assert (Present (Access_Definition (Component_Def)));
5434 -- Indicate that the anonymous access type is created by the
5435 -- array type declaration.
5437 Element_Type := Access_Definition
5439 N => Access_Definition (Component_Def));
5440 Set_Is_Local_Anonymous_Access (Element_Type);
5442 -- Propagate the parent. This field is needed if we have to generate
5443 -- the master_id associated with an anonymous access to task type
5444 -- component (see Expand_N_Full_Type_Declaration.Build_Master)
5446 Set_Parent (Element_Type, Parent (T));
5448 -- Ada 2005 (AI-230): In case of components that are anonymous access
5449 -- types the level of accessibility depends on the enclosing type
5452 Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230)
5454 -- Ada 2005 (AI-254)
5457 CD : constant Node_Id :=
5458 Access_To_Subprogram_Definition
5459 (Access_Definition (Component_Def));
5461 if Present (CD) and then Protected_Present (CD) then
5463 Replace_Anonymous_Access_To_Protected_Subprogram (Def);
5468 -- Constrained array case
5471 T := Create_Itype (E_Void, P, Related_Id, 'T');
5474 if Nkind (Def) = N_Constrained_Array_Definition then
5476 -- Establish Implicit_Base as unconstrained base type
5478 Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B');
5480 Set_Etype (Implicit_Base, Implicit_Base);
5481 Set_Scope (Implicit_Base, Current_Scope);
5482 Set_Has_Delayed_Freeze (Implicit_Base);
5483 Set_Default_SSO (Implicit_Base);
5485 -- The constrained array type is a subtype of the unconstrained one
5487 Set_Ekind (T, E_Array_Subtype);
5488 Init_Size_Align (T);
5489 Set_Etype (T, Implicit_Base);
5490 Set_Scope (T, Current_Scope);
5491 Set_Is_Constrained (T);
5493 First (Discrete_Subtype_Definitions (Def)));
5494 Set_Has_Delayed_Freeze (T);
5496 -- Complete setup of implicit base type
5498 Set_First_Index (Implicit_Base, First_Index (T));
5499 Set_Component_Type (Implicit_Base, Element_Type);
5500 Set_Has_Task (Implicit_Base, Has_Task (Element_Type));
5501 Set_Has_Protected (Implicit_Base, Has_Protected (Element_Type));
5502 Set_Component_Size (Implicit_Base, Uint_0);
5503 Set_Packed_Array_Impl_Type (Implicit_Base, Empty);
5504 Set_Has_Controlled_Component (Implicit_Base,
5505 Has_Controlled_Component (Element_Type)
5506 or else Is_Controlled (Element_Type));
5507 Set_Finalize_Storage_Only (Implicit_Base,
5508 Finalize_Storage_Only (Element_Type));
5510 -- Inherit the "ghostness" from the constrained array type
5512 if Is_Ghost_Entity (T) or else Ghost_Mode > None then
5513 Set_Is_Ghost_Entity (Implicit_Base);
5516 -- Unconstrained array case
5519 Set_Ekind (T, E_Array_Type);
5520 Init_Size_Align (T);
5522 Set_Scope (T, Current_Scope);
5523 Set_Component_Size (T, Uint_0);
5524 Set_Is_Constrained (T, False);
5525 Set_First_Index (T, First (Subtype_Marks (Def)));
5526 Set_Has_Delayed_Freeze (T, True);
5527 Set_Has_Task (T, Has_Task (Element_Type));
5528 Set_Has_Protected (T, Has_Protected (Element_Type));
5529 Set_Has_Controlled_Component (T, Has_Controlled_Component
5532 Is_Controlled (Element_Type));
5533 Set_Finalize_Storage_Only (T, Finalize_Storage_Only
5535 Set_Default_SSO (T);
5538 -- Common attributes for both cases
5540 Set_Component_Type (Base_Type (T), Element_Type);
5541 Set_Packed_Array_Impl_Type (T, Empty);
5543 if Aliased_Present (Component_Definition (Def)) then
5544 Check_SPARK_05_Restriction
5545 ("aliased is not allowed", Component_Definition (Def));
5546 Set_Has_Aliased_Components (Etype (T));
5549 -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the
5550 -- array type to ensure that objects of this type are initialized.
5552 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (Element_Type) then
5553 Set_Can_Never_Be_Null (T);
5555 if Null_Exclusion_Present (Component_Definition (Def))
5557 -- No need to check itypes because in their case this check was
5558 -- done at their point of creation
5560 and then not Is_Itype (Element_Type)
5563 ("`NOT NULL` not allowed (null already excluded)",
5564 Subtype_Indication (Component_Definition (Def)));
5568 Priv := Private_Component (Element_Type);
5570 if Present (Priv) then
5572 -- Check for circular definitions
5574 if Priv = Any_Type then
5575 Set_Component_Type (Etype (T), Any_Type);
5577 -- There is a gap in the visibility of operations on the composite
5578 -- type only if the component type is defined in a different scope.
5580 elsif Scope (Priv) = Current_Scope then
5583 elsif Is_Limited_Type (Priv) then
5584 Set_Is_Limited_Composite (Etype (T));
5585 Set_Is_Limited_Composite (T);
5587 Set_Is_Private_Composite (Etype (T));
5588 Set_Is_Private_Composite (T);
5592 -- A syntax error in the declaration itself may lead to an empty index
5593 -- list, in which case do a minimal patch.
5595 if No (First_Index (T)) then
5596 Error_Msg_N ("missing index definition in array type declaration", T);
5599 Indexes : constant List_Id :=
5600 New_List (New_Occurrence_Of (Any_Id, Sloc (T)));
5602 Set_Discrete_Subtype_Definitions (Def, Indexes);
5603 Set_First_Index (T, First (Indexes));
5608 -- Create a concatenation operator for the new type. Internal array
5609 -- types created for packed entities do not need such, they are
5610 -- compatible with the user-defined type.
5612 if Number_Dimensions (T) = 1
5613 and then not Is_Packed_Array_Impl_Type (T)
5615 New_Concatenation_Op (T);
5618 -- In the case of an unconstrained array the parser has already verified
5619 -- that all the indexes are unconstrained but we still need to make sure
5620 -- that the element type is constrained.
5622 if Is_Indefinite_Subtype (Element_Type) then
5624 ("unconstrained element type in array declaration",
5625 Subtype_Indication (Component_Def));
5627 elsif Is_Abstract_Type (Element_Type) then
5629 ("the type of a component cannot be abstract",
5630 Subtype_Indication (Component_Def));
5633 -- There may be an invariant declared for the component type, but
5634 -- the construction of the component invariant checking procedure
5635 -- takes place during expansion.
5636 end Array_Type_Declaration;
5638 ------------------------------------------------------
5639 -- Replace_Anonymous_Access_To_Protected_Subprogram --
5640 ------------------------------------------------------
5642 function Replace_Anonymous_Access_To_Protected_Subprogram
5643 (N : Node_Id) return Entity_Id
5645 Loc : constant Source_Ptr := Sloc (N);
5647 Curr_Scope : constant Scope_Stack_Entry :=
5648 Scope_Stack.Table (Scope_Stack.Last);
5650 Anon : constant Entity_Id := Make_Temporary (Loc, 'S');
5653 -- Access definition in declaration
5656 -- Object definition or formal definition with an access definition
5659 -- Declaration of anonymous access to subprogram type
5662 -- Original specification in access to subprogram
5667 Set_Is_Internal (Anon);
5670 when N_Component_Declaration |
5671 N_Unconstrained_Array_Definition |
5672 N_Constrained_Array_Definition =>
5673 Comp := Component_Definition (N);
5674 Acc := Access_Definition (Comp);
5676 when N_Discriminant_Specification =>
5677 Comp := Discriminant_Type (N);
5680 when N_Parameter_Specification =>
5681 Comp := Parameter_Type (N);
5684 when N_Access_Function_Definition =>
5685 Comp := Result_Definition (N);
5688 when N_Object_Declaration =>
5689 Comp := Object_Definition (N);
5692 when N_Function_Specification =>
5693 Comp := Result_Definition (N);
5697 raise Program_Error;
5700 Spec := Access_To_Subprogram_Definition (Acc);
5703 Make_Full_Type_Declaration (Loc,
5704 Defining_Identifier => Anon,
5705 Type_Definition => Copy_Separate_Tree (Spec));
5707 Mark_Rewrite_Insertion (Decl);
5709 -- In ASIS mode, analyze the profile on the original node, because
5710 -- the separate copy does not provide enough links to recover the
5711 -- original tree. Analysis is limited to type annotations, within
5712 -- a temporary scope that serves as an anonymous subprogram to collect
5713 -- otherwise useless temporaries and itypes.
5717 Typ : constant Entity_Id := Make_Temporary (Loc, 'S');
5720 if Nkind (Spec) = N_Access_Function_Definition then
5721 Set_Ekind (Typ, E_Function);
5723 Set_Ekind (Typ, E_Procedure);
5726 Set_Parent (Typ, N);
5727 Set_Scope (Typ, Current_Scope);
5730 Process_Formals (Parameter_Specifications (Spec), Spec);
5732 if Nkind (Spec) = N_Access_Function_Definition then
5734 Def : constant Node_Id := Result_Definition (Spec);
5737 -- The result might itself be an anonymous access type, so
5740 if Nkind (Def) = N_Access_Definition then
5741 if Present (Access_To_Subprogram_Definition (Def)) then
5744 Replace_Anonymous_Access_To_Protected_Subprogram
5747 Find_Type (Subtype_Mark (Def));
5760 -- Insert the new declaration in the nearest enclosing scope. If the
5761 -- node is a body and N is its return type, the declaration belongs in
5762 -- the enclosing scope.
5766 if Nkind (P) = N_Subprogram_Body
5767 and then Nkind (N) = N_Function_Specification
5772 while Present (P) and then not Has_Declarations (P) loop
5776 pragma Assert (Present (P));
5778 if Nkind (P) = N_Package_Specification then
5779 Prepend (Decl, Visible_Declarations (P));
5781 Prepend (Decl, Declarations (P));
5784 -- Replace the anonymous type with an occurrence of the new declaration.
5785 -- In all cases the rewritten node does not have the null-exclusion
5786 -- attribute because (if present) it was already inherited by the
5787 -- anonymous entity (Anon). Thus, in case of components we do not
5788 -- inherit this attribute.
5790 if Nkind (N) = N_Parameter_Specification then
5791 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5792 Set_Etype (Defining_Identifier (N), Anon);
5793 Set_Null_Exclusion_Present (N, False);
5795 elsif Nkind (N) = N_Object_Declaration then
5796 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5797 Set_Etype (Defining_Identifier (N), Anon);
5799 elsif Nkind (N) = N_Access_Function_Definition then
5800 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5802 elsif Nkind (N) = N_Function_Specification then
5803 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5804 Set_Etype (Defining_Unit_Name (N), Anon);
5808 Make_Component_Definition (Loc,
5809 Subtype_Indication => New_Occurrence_Of (Anon, Loc)));
5812 Mark_Rewrite_Insertion (Comp);
5814 if Nkind_In (N, N_Object_Declaration, N_Access_Function_Definition) then
5818 -- Temporarily remove the current scope (record or subprogram) from
5819 -- the stack to add the new declarations to the enclosing scope.
5821 Scope_Stack.Decrement_Last;
5823 Set_Is_Itype (Anon);
5824 Scope_Stack.Append (Curr_Scope);
5827 Set_Ekind (Anon, E_Anonymous_Access_Protected_Subprogram_Type);
5828 Set_Can_Use_Internal_Rep (Anon, not Always_Compatible_Rep_On_Target);
5830 end Replace_Anonymous_Access_To_Protected_Subprogram;
5832 -------------------------------
5833 -- Build_Derived_Access_Type --
5834 -------------------------------
5836 procedure Build_Derived_Access_Type
5838 Parent_Type : Entity_Id;
5839 Derived_Type : Entity_Id)
5841 S : constant Node_Id := Subtype_Indication (Type_Definition (N));
5843 Desig_Type : Entity_Id;
5845 Discr_Con_Elist : Elist_Id;
5846 Discr_Con_El : Elmt_Id;
5850 -- Set the designated type so it is available in case this is an access
5851 -- to a self-referential type, e.g. a standard list type with a next
5852 -- pointer. Will be reset after subtype is built.
5854 Set_Directly_Designated_Type
5855 (Derived_Type, Designated_Type (Parent_Type));
5857 Subt := Process_Subtype (S, N);
5859 if Nkind (S) /= N_Subtype_Indication
5860 and then Subt /= Base_Type (Subt)
5862 Set_Ekind (Derived_Type, E_Access_Subtype);
5865 if Ekind (Derived_Type) = E_Access_Subtype then
5867 Pbase : constant Entity_Id := Base_Type (Parent_Type);
5868 Ibase : constant Entity_Id :=
5869 Create_Itype (Ekind (Pbase), N, Derived_Type, 'B');
5870 Svg_Chars : constant Name_Id := Chars (Ibase);
5871 Svg_Next_E : constant Entity_Id := Next_Entity (Ibase);
5874 Copy_Node (Pbase, Ibase);
5876 Set_Chars (Ibase, Svg_Chars);
5877 Set_Next_Entity (Ibase, Svg_Next_E);
5878 Set_Sloc (Ibase, Sloc (Derived_Type));
5879 Set_Scope (Ibase, Scope (Derived_Type));
5880 Set_Freeze_Node (Ibase, Empty);
5881 Set_Is_Frozen (Ibase, False);
5882 Set_Comes_From_Source (Ibase, False);
5883 Set_Is_First_Subtype (Ibase, False);
5885 Set_Etype (Ibase, Pbase);
5886 Set_Etype (Derived_Type, Ibase);
5890 Set_Directly_Designated_Type
5891 (Derived_Type, Designated_Type (Subt));
5893 Set_Is_Constrained (Derived_Type, Is_Constrained (Subt));
5894 Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type));
5895 Set_Size_Info (Derived_Type, Parent_Type);
5896 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
5897 Set_Depends_On_Private (Derived_Type,
5898 Has_Private_Component (Derived_Type));
5899 Conditional_Delay (Derived_Type, Subt);
5901 -- Ada 2005 (AI-231): Set the null-exclusion attribute, and verify
5902 -- that it is not redundant.
5904 if Null_Exclusion_Present (Type_Definition (N)) then
5905 Set_Can_Never_Be_Null (Derived_Type);
5907 -- What is with the "AND THEN FALSE" here ???
5909 if Can_Never_Be_Null (Parent_Type)
5913 ("`NOT NULL` not allowed (& already excludes null)",
5917 elsif Can_Never_Be_Null (Parent_Type) then
5918 Set_Can_Never_Be_Null (Derived_Type);
5921 -- Note: we do not copy the Storage_Size_Variable, since we always go to
5922 -- the root type for this information.
5924 -- Apply range checks to discriminants for derived record case
5925 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
5927 Desig_Type := Designated_Type (Derived_Type);
5928 if Is_Composite_Type (Desig_Type)
5929 and then (not Is_Array_Type (Desig_Type))
5930 and then Has_Discriminants (Desig_Type)
5931 and then Base_Type (Desig_Type) /= Desig_Type
5933 Discr_Con_Elist := Discriminant_Constraint (Desig_Type);
5934 Discr_Con_El := First_Elmt (Discr_Con_Elist);
5936 Discr := First_Discriminant (Base_Type (Desig_Type));
5937 while Present (Discr_Con_El) loop
5938 Apply_Range_Check (Node (Discr_Con_El), Etype (Discr));
5939 Next_Elmt (Discr_Con_El);
5940 Next_Discriminant (Discr);
5943 end Build_Derived_Access_Type;
5945 ------------------------------
5946 -- Build_Derived_Array_Type --
5947 ------------------------------
5949 procedure Build_Derived_Array_Type
5951 Parent_Type : Entity_Id;
5952 Derived_Type : Entity_Id)
5954 Loc : constant Source_Ptr := Sloc (N);
5955 Tdef : constant Node_Id := Type_Definition (N);
5956 Indic : constant Node_Id := Subtype_Indication (Tdef);
5957 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
5958 Implicit_Base : Entity_Id;
5959 New_Indic : Node_Id;
5961 procedure Make_Implicit_Base;
5962 -- If the parent subtype is constrained, the derived type is a subtype
5963 -- of an implicit base type derived from the parent base.
5965 ------------------------
5966 -- Make_Implicit_Base --
5967 ------------------------
5969 procedure Make_Implicit_Base is
5972 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
5974 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
5975 Set_Etype (Implicit_Base, Parent_Base);
5977 Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base);
5978 Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base);
5980 Set_Has_Delayed_Freeze (Implicit_Base, True);
5982 -- Inherit the "ghostness" from the parent base type
5984 if Is_Ghost_Entity (Parent_Base) or else Ghost_Mode > None then
5985 Set_Is_Ghost_Entity (Implicit_Base);
5987 end Make_Implicit_Base;
5989 -- Start of processing for Build_Derived_Array_Type
5992 if not Is_Constrained (Parent_Type) then
5993 if Nkind (Indic) /= N_Subtype_Indication then
5994 Set_Ekind (Derived_Type, E_Array_Type);
5996 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
5997 Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type);
5999 Set_Has_Delayed_Freeze (Derived_Type, True);
6003 Set_Etype (Derived_Type, Implicit_Base);
6006 Make_Subtype_Declaration (Loc,
6007 Defining_Identifier => Derived_Type,
6008 Subtype_Indication =>
6009 Make_Subtype_Indication (Loc,
6010 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6011 Constraint => Constraint (Indic)));
6013 Rewrite (N, New_Indic);
6018 if Nkind (Indic) /= N_Subtype_Indication then
6021 Set_Ekind (Derived_Type, Ekind (Parent_Type));
6022 Set_Etype (Derived_Type, Implicit_Base);
6023 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
6026 Error_Msg_N ("illegal constraint on constrained type", Indic);
6030 -- If parent type is not a derived type itself, and is declared in
6031 -- closed scope (e.g. a subprogram), then we must explicitly introduce
6032 -- the new type's concatenation operator since Derive_Subprograms
6033 -- will not inherit the parent's operator. If the parent type is
6034 -- unconstrained, the operator is of the unconstrained base type.
6036 if Number_Dimensions (Parent_Type) = 1
6037 and then not Is_Limited_Type (Parent_Type)
6038 and then not Is_Derived_Type (Parent_Type)
6039 and then not Is_Package_Or_Generic_Package
6040 (Scope (Base_Type (Parent_Type)))
6042 if not Is_Constrained (Parent_Type)
6043 and then Is_Constrained (Derived_Type)
6045 New_Concatenation_Op (Implicit_Base);
6047 New_Concatenation_Op (Derived_Type);
6050 end Build_Derived_Array_Type;
6052 -----------------------------------
6053 -- Build_Derived_Concurrent_Type --
6054 -----------------------------------
6056 procedure Build_Derived_Concurrent_Type
6058 Parent_Type : Entity_Id;
6059 Derived_Type : Entity_Id)
6061 Loc : constant Source_Ptr := Sloc (N);
6063 Corr_Record : constant Entity_Id := Make_Temporary (Loc, 'C');
6064 Corr_Decl : Node_Id;
6065 Corr_Decl_Needed : Boolean;
6066 -- If the derived type has fewer discriminants than its parent, the
6067 -- corresponding record is also a derived type, in order to account for
6068 -- the bound discriminants. We create a full type declaration for it in
6071 Constraint_Present : constant Boolean :=
6072 Nkind (Subtype_Indication (Type_Definition (N))) =
6073 N_Subtype_Indication;
6075 D_Constraint : Node_Id;
6076 New_Constraint : Elist_Id;
6077 Old_Disc : Entity_Id;
6078 New_Disc : Entity_Id;
6082 Set_Stored_Constraint (Derived_Type, No_Elist);
6083 Corr_Decl_Needed := False;
6086 if Present (Discriminant_Specifications (N))
6087 and then Constraint_Present
6089 Old_Disc := First_Discriminant (Parent_Type);
6090 New_Disc := First (Discriminant_Specifications (N));
6091 while Present (New_Disc) and then Present (Old_Disc) loop
6092 Next_Discriminant (Old_Disc);
6097 if Present (Old_Disc) and then Expander_Active then
6099 -- The new type has fewer discriminants, so we need to create a new
6100 -- corresponding record, which is derived from the corresponding
6101 -- record of the parent, and has a stored constraint that captures
6102 -- the values of the discriminant constraints. The corresponding
6103 -- record is needed only if expander is active and code generation is
6106 -- The type declaration for the derived corresponding record has the
6107 -- same discriminant part and constraints as the current declaration.
6108 -- Copy the unanalyzed tree to build declaration.
6110 Corr_Decl_Needed := True;
6111 New_N := Copy_Separate_Tree (N);
6114 Make_Full_Type_Declaration (Loc,
6115 Defining_Identifier => Corr_Record,
6116 Discriminant_Specifications =>
6117 Discriminant_Specifications (New_N),
6119 Make_Derived_Type_Definition (Loc,
6120 Subtype_Indication =>
6121 Make_Subtype_Indication (Loc,
6124 (Corresponding_Record_Type (Parent_Type), Loc),
6127 (Subtype_Indication (Type_Definition (New_N))))));
6130 -- Copy Storage_Size and Relative_Deadline variables if task case
6132 if Is_Task_Type (Parent_Type) then
6133 Set_Storage_Size_Variable (Derived_Type,
6134 Storage_Size_Variable (Parent_Type));
6135 Set_Relative_Deadline_Variable (Derived_Type,
6136 Relative_Deadline_Variable (Parent_Type));
6139 if Present (Discriminant_Specifications (N)) then
6140 Push_Scope (Derived_Type);
6141 Check_Or_Process_Discriminants (N, Derived_Type);
6143 if Constraint_Present then
6145 Expand_To_Stored_Constraint
6147 Build_Discriminant_Constraints
6149 Subtype_Indication (Type_Definition (N)), True));
6154 elsif Constraint_Present then
6156 -- Build constrained subtype, copying the constraint, and derive
6157 -- from it to create a derived constrained type.
6160 Loc : constant Source_Ptr := Sloc (N);
6161 Anon : constant Entity_Id :=
6162 Make_Defining_Identifier (Loc,
6163 Chars => New_External_Name (Chars (Derived_Type), 'T'));
6168 Make_Subtype_Declaration (Loc,
6169 Defining_Identifier => Anon,
6170 Subtype_Indication =>
6171 New_Copy_Tree (Subtype_Indication (Type_Definition (N))));
6172 Insert_Before (N, Decl);
6175 Rewrite (Subtype_Indication (Type_Definition (N)),
6176 New_Occurrence_Of (Anon, Loc));
6177 Set_Analyzed (Derived_Type, False);
6183 -- By default, operations and private data are inherited from parent.
6184 -- However, in the presence of bound discriminants, a new corresponding
6185 -- record will be created, see below.
6187 Set_Has_Discriminants
6188 (Derived_Type, Has_Discriminants (Parent_Type));
6189 Set_Corresponding_Record_Type
6190 (Derived_Type, Corresponding_Record_Type (Parent_Type));
6192 -- Is_Constrained is set according the parent subtype, but is set to
6193 -- False if the derived type is declared with new discriminants.
6197 (Is_Constrained (Parent_Type) or else Constraint_Present)
6198 and then not Present (Discriminant_Specifications (N)));
6200 if Constraint_Present then
6201 if not Has_Discriminants (Parent_Type) then
6202 Error_Msg_N ("untagged parent must have discriminants", N);
6204 elsif Present (Discriminant_Specifications (N)) then
6206 -- Verify that new discriminants are used to constrain old ones
6211 (Constraint (Subtype_Indication (Type_Definition (N)))));
6213 Old_Disc := First_Discriminant (Parent_Type);
6215 while Present (D_Constraint) loop
6216 if Nkind (D_Constraint) /= N_Discriminant_Association then
6218 -- Positional constraint. If it is a reference to a new
6219 -- discriminant, it constrains the corresponding old one.
6221 if Nkind (D_Constraint) = N_Identifier then
6222 New_Disc := First_Discriminant (Derived_Type);
6223 while Present (New_Disc) loop
6224 exit when Chars (New_Disc) = Chars (D_Constraint);
6225 Next_Discriminant (New_Disc);
6228 if Present (New_Disc) then
6229 Set_Corresponding_Discriminant (New_Disc, Old_Disc);
6233 Next_Discriminant (Old_Disc);
6235 -- if this is a named constraint, search by name for the old
6236 -- discriminants constrained by the new one.
6238 elsif Nkind (Expression (D_Constraint)) = N_Identifier then
6240 -- Find new discriminant with that name
6242 New_Disc := First_Discriminant (Derived_Type);
6243 while Present (New_Disc) loop
6245 Chars (New_Disc) = Chars (Expression (D_Constraint));
6246 Next_Discriminant (New_Disc);
6249 if Present (New_Disc) then
6251 -- Verify that new discriminant renames some discriminant
6252 -- of the parent type, and associate the new discriminant
6253 -- with one or more old ones that it renames.
6259 Selector := First (Selector_Names (D_Constraint));
6260 while Present (Selector) loop
6261 Old_Disc := First_Discriminant (Parent_Type);
6262 while Present (Old_Disc) loop
6263 exit when Chars (Old_Disc) = Chars (Selector);
6264 Next_Discriminant (Old_Disc);
6267 if Present (Old_Disc) then
6268 Set_Corresponding_Discriminant
6269 (New_Disc, Old_Disc);
6278 Next (D_Constraint);
6281 New_Disc := First_Discriminant (Derived_Type);
6282 while Present (New_Disc) loop
6283 if No (Corresponding_Discriminant (New_Disc)) then
6285 ("new discriminant& must constrain old one", N, New_Disc);
6288 Subtypes_Statically_Compatible
6290 Etype (Corresponding_Discriminant (New_Disc)))
6293 ("& not statically compatible with parent discriminant",
6297 Next_Discriminant (New_Disc);
6301 elsif Present (Discriminant_Specifications (N)) then
6303 ("missing discriminant constraint in untagged derivation", N);
6306 -- The entity chain of the derived type includes the new discriminants
6307 -- but shares operations with the parent.
6309 if Present (Discriminant_Specifications (N)) then
6310 Old_Disc := First_Discriminant (Parent_Type);
6311 while Present (Old_Disc) loop
6312 if No (Next_Entity (Old_Disc))
6313 or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant
6316 (Last_Entity (Derived_Type), Next_Entity (Old_Disc));
6320 Next_Discriminant (Old_Disc);
6324 Set_First_Entity (Derived_Type, First_Entity (Parent_Type));
6325 if Has_Discriminants (Parent_Type) then
6326 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6327 Set_Discriminant_Constraint (
6328 Derived_Type, Discriminant_Constraint (Parent_Type));
6332 Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type));
6334 Set_Has_Completion (Derived_Type);
6336 if Corr_Decl_Needed then
6337 Set_Stored_Constraint (Derived_Type, New_Constraint);
6338 Insert_After (N, Corr_Decl);
6339 Analyze (Corr_Decl);
6340 Set_Corresponding_Record_Type (Derived_Type, Corr_Record);
6342 end Build_Derived_Concurrent_Type;
6344 ------------------------------------
6345 -- Build_Derived_Enumeration_Type --
6346 ------------------------------------
6348 procedure Build_Derived_Enumeration_Type
6350 Parent_Type : Entity_Id;
6351 Derived_Type : Entity_Id)
6353 Loc : constant Source_Ptr := Sloc (N);
6354 Def : constant Node_Id := Type_Definition (N);
6355 Indic : constant Node_Id := Subtype_Indication (Def);
6356 Implicit_Base : Entity_Id;
6357 Literal : Entity_Id;
6358 New_Lit : Entity_Id;
6359 Literals_List : List_Id;
6360 Type_Decl : Node_Id;
6362 Rang_Expr : Node_Id;
6365 -- Since types Standard.Character and Standard.[Wide_]Wide_Character do
6366 -- not have explicit literals lists we need to process types derived
6367 -- from them specially. This is handled by Derived_Standard_Character.
6368 -- If the parent type is a generic type, there are no literals either,
6369 -- and we construct the same skeletal representation as for the generic
6372 if Is_Standard_Character_Type (Parent_Type) then
6373 Derived_Standard_Character (N, Parent_Type, Derived_Type);
6375 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
6381 if Nkind (Indic) /= N_Subtype_Indication then
6383 Make_Attribute_Reference (Loc,
6384 Attribute_Name => Name_First,
6385 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6386 Set_Etype (Lo, Derived_Type);
6389 Make_Attribute_Reference (Loc,
6390 Attribute_Name => Name_Last,
6391 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6392 Set_Etype (Hi, Derived_Type);
6394 Set_Scalar_Range (Derived_Type,
6400 -- Analyze subtype indication and verify compatibility
6401 -- with parent type.
6403 if Base_Type (Process_Subtype (Indic, N)) /=
6404 Base_Type (Parent_Type)
6407 ("illegal constraint for formal discrete type", N);
6413 -- If a constraint is present, analyze the bounds to catch
6414 -- premature usage of the derived literals.
6416 if Nkind (Indic) = N_Subtype_Indication
6417 and then Nkind (Range_Expression (Constraint (Indic))) = N_Range
6419 Analyze (Low_Bound (Range_Expression (Constraint (Indic))));
6420 Analyze (High_Bound (Range_Expression (Constraint (Indic))));
6423 -- Introduce an implicit base type for the derived type even if there
6424 -- is no constraint attached to it, since this seems closer to the
6425 -- Ada semantics. Build a full type declaration tree for the derived
6426 -- type using the implicit base type as the defining identifier. The
6427 -- build a subtype declaration tree which applies the constraint (if
6428 -- any) have it replace the derived type declaration.
6430 Literal := First_Literal (Parent_Type);
6431 Literals_List := New_List;
6432 while Present (Literal)
6433 and then Ekind (Literal) = E_Enumeration_Literal
6435 -- Literals of the derived type have the same representation as
6436 -- those of the parent type, but this representation can be
6437 -- overridden by an explicit representation clause. Indicate
6438 -- that there is no explicit representation given yet. These
6439 -- derived literals are implicit operations of the new type,
6440 -- and can be overridden by explicit ones.
6442 if Nkind (Literal) = N_Defining_Character_Literal then
6444 Make_Defining_Character_Literal (Loc, Chars (Literal));
6446 New_Lit := Make_Defining_Identifier (Loc, Chars (Literal));
6449 Set_Ekind (New_Lit, E_Enumeration_Literal);
6450 Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal));
6451 Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal));
6452 Set_Enumeration_Rep_Expr (New_Lit, Empty);
6453 Set_Alias (New_Lit, Literal);
6454 Set_Is_Known_Valid (New_Lit, True);
6456 Append (New_Lit, Literals_List);
6457 Next_Literal (Literal);
6461 Make_Defining_Identifier (Sloc (Derived_Type),
6462 Chars => New_External_Name (Chars (Derived_Type), 'B'));
6464 -- Indicate the proper nature of the derived type. This must be done
6465 -- before analysis of the literals, to recognize cases when a literal
6466 -- may be hidden by a previous explicit function definition (cf.
6469 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
6470 Set_Etype (Derived_Type, Implicit_Base);
6473 Make_Full_Type_Declaration (Loc,
6474 Defining_Identifier => Implicit_Base,
6475 Discriminant_Specifications => No_List,
6477 Make_Enumeration_Type_Definition (Loc, Literals_List));
6479 Mark_Rewrite_Insertion (Type_Decl);
6480 Insert_Before (N, Type_Decl);
6481 Analyze (Type_Decl);
6483 -- After the implicit base is analyzed its Etype needs to be changed
6484 -- to reflect the fact that it is derived from the parent type which
6485 -- was ignored during analysis. We also set the size at this point.
6487 Set_Etype (Implicit_Base, Parent_Type);
6489 Set_Size_Info (Implicit_Base, Parent_Type);
6490 Set_RM_Size (Implicit_Base, RM_Size (Parent_Type));
6491 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type));
6493 -- Copy other flags from parent type
6495 Set_Has_Non_Standard_Rep
6496 (Implicit_Base, Has_Non_Standard_Rep
6498 Set_Has_Pragma_Ordered
6499 (Implicit_Base, Has_Pragma_Ordered
6501 Set_Has_Delayed_Freeze (Implicit_Base);
6503 -- Process the subtype indication including a validation check on the
6504 -- constraint, if any. If a constraint is given, its bounds must be
6505 -- implicitly converted to the new type.
6507 if Nkind (Indic) = N_Subtype_Indication then
6509 R : constant Node_Id :=
6510 Range_Expression (Constraint (Indic));
6513 if Nkind (R) = N_Range then
6514 Hi := Build_Scalar_Bound
6515 (High_Bound (R), Parent_Type, Implicit_Base);
6516 Lo := Build_Scalar_Bound
6517 (Low_Bound (R), Parent_Type, Implicit_Base);
6520 -- Constraint is a Range attribute. Replace with explicit
6521 -- mention of the bounds of the prefix, which must be a
6524 Analyze (Prefix (R));
6526 Convert_To (Implicit_Base,
6527 Make_Attribute_Reference (Loc,
6528 Attribute_Name => Name_Last,
6530 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6533 Convert_To (Implicit_Base,
6534 Make_Attribute_Reference (Loc,
6535 Attribute_Name => Name_First,
6537 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6544 (Type_High_Bound (Parent_Type),
6545 Parent_Type, Implicit_Base);
6548 (Type_Low_Bound (Parent_Type),
6549 Parent_Type, Implicit_Base);
6557 -- If we constructed a default range for the case where no range
6558 -- was given, then the expressions in the range must not freeze
6559 -- since they do not correspond to expressions in the source.
6561 if Nkind (Indic) /= N_Subtype_Indication then
6562 Set_Must_Not_Freeze (Lo);
6563 Set_Must_Not_Freeze (Hi);
6564 Set_Must_Not_Freeze (Rang_Expr);
6568 Make_Subtype_Declaration (Loc,
6569 Defining_Identifier => Derived_Type,
6570 Subtype_Indication =>
6571 Make_Subtype_Indication (Loc,
6572 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6574 Make_Range_Constraint (Loc,
6575 Range_Expression => Rang_Expr))));
6579 -- Propagate the aspects from the original type declaration to the
6580 -- declaration of the implicit base.
6582 Move_Aspects (From => Original_Node (N), To => Type_Decl);
6584 -- Apply a range check. Since this range expression doesn't have an
6585 -- Etype, we have to specifically pass the Source_Typ parameter. Is
6588 if Nkind (Indic) = N_Subtype_Indication then
6590 (Range_Expression (Constraint (Indic)), Parent_Type,
6591 Source_Typ => Entity (Subtype_Mark (Indic)));
6594 end Build_Derived_Enumeration_Type;
6596 --------------------------------
6597 -- Build_Derived_Numeric_Type --
6598 --------------------------------
6600 procedure Build_Derived_Numeric_Type
6602 Parent_Type : Entity_Id;
6603 Derived_Type : Entity_Id)
6605 Loc : constant Source_Ptr := Sloc (N);
6606 Tdef : constant Node_Id := Type_Definition (N);
6607 Indic : constant Node_Id := Subtype_Indication (Tdef);
6608 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
6609 No_Constraint : constant Boolean := Nkind (Indic) /=
6610 N_Subtype_Indication;
6611 Implicit_Base : Entity_Id;
6617 -- Process the subtype indication including a validation check on
6618 -- the constraint if any.
6620 Discard_Node (Process_Subtype (Indic, N));
6622 -- Introduce an implicit base type for the derived type even if there
6623 -- is no constraint attached to it, since this seems closer to the Ada
6627 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
6629 Set_Etype (Implicit_Base, Parent_Base);
6630 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
6631 Set_Size_Info (Implicit_Base, Parent_Base);
6632 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base));
6633 Set_Parent (Implicit_Base, Parent (Derived_Type));
6634 Set_Is_Known_Valid (Implicit_Base, Is_Known_Valid (Parent_Base));
6636 -- Set RM Size for discrete type or decimal fixed-point type
6637 -- Ordinary fixed-point is excluded, why???
6639 if Is_Discrete_Type (Parent_Base)
6640 or else Is_Decimal_Fixed_Point_Type (Parent_Base)
6642 Set_RM_Size (Implicit_Base, RM_Size (Parent_Base));
6645 Set_Has_Delayed_Freeze (Implicit_Base);
6647 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
6648 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
6650 Set_Scalar_Range (Implicit_Base,
6655 if Has_Infinities (Parent_Base) then
6656 Set_Includes_Infinities (Scalar_Range (Implicit_Base));
6659 -- The Derived_Type, which is the entity of the declaration, is a
6660 -- subtype of the implicit base. Its Ekind is a subtype, even in the
6661 -- absence of an explicit constraint.
6663 Set_Etype (Derived_Type, Implicit_Base);
6665 -- If we did not have a constraint, then the Ekind is set from the
6666 -- parent type (otherwise Process_Subtype has set the bounds)
6668 if No_Constraint then
6669 Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type)));
6672 -- If we did not have a range constraint, then set the range from the
6673 -- parent type. Otherwise, the Process_Subtype call has set the bounds.
6675 if No_Constraint or else not Has_Range_Constraint (Indic) then
6676 Set_Scalar_Range (Derived_Type,
6678 Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)),
6679 High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type))));
6680 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6682 if Has_Infinities (Parent_Type) then
6683 Set_Includes_Infinities (Scalar_Range (Derived_Type));
6686 Set_Is_Known_Valid (Derived_Type, Is_Known_Valid (Parent_Type));
6689 Set_Is_Descendent_Of_Address (Derived_Type,
6690 Is_Descendent_Of_Address (Parent_Type));
6691 Set_Is_Descendent_Of_Address (Implicit_Base,
6692 Is_Descendent_Of_Address (Parent_Type));
6694 -- Set remaining type-specific fields, depending on numeric type
6696 if Is_Modular_Integer_Type (Parent_Type) then
6697 Set_Modulus (Implicit_Base, Modulus (Parent_Base));
6699 Set_Non_Binary_Modulus
6700 (Implicit_Base, Non_Binary_Modulus (Parent_Base));
6703 (Implicit_Base, Is_Known_Valid (Parent_Base));
6705 elsif Is_Floating_Point_Type (Parent_Type) then
6707 -- Digits of base type is always copied from the digits value of
6708 -- the parent base type, but the digits of the derived type will
6709 -- already have been set if there was a constraint present.
6711 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6712 Set_Float_Rep (Implicit_Base, Float_Rep (Parent_Base));
6714 if No_Constraint then
6715 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type));
6718 elsif Is_Fixed_Point_Type (Parent_Type) then
6720 -- Small of base type and derived type are always copied from the
6721 -- parent base type, since smalls never change. The delta of the
6722 -- base type is also copied from the parent base type. However the
6723 -- delta of the derived type will have been set already if a
6724 -- constraint was present.
6726 Set_Small_Value (Derived_Type, Small_Value (Parent_Base));
6727 Set_Small_Value (Implicit_Base, Small_Value (Parent_Base));
6728 Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base));
6730 if No_Constraint then
6731 Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type));
6734 -- The scale and machine radix in the decimal case are always
6735 -- copied from the parent base type.
6737 if Is_Decimal_Fixed_Point_Type (Parent_Type) then
6738 Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base));
6739 Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base));
6741 Set_Machine_Radix_10
6742 (Derived_Type, Machine_Radix_10 (Parent_Base));
6743 Set_Machine_Radix_10
6744 (Implicit_Base, Machine_Radix_10 (Parent_Base));
6746 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6748 if No_Constraint then
6749 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base));
6752 -- the analysis of the subtype_indication sets the
6753 -- digits value of the derived type.
6760 if Is_Integer_Type (Parent_Type) then
6761 Set_Has_Shift_Operator
6762 (Implicit_Base, Has_Shift_Operator (Parent_Type));
6765 -- The type of the bounds is that of the parent type, and they
6766 -- must be converted to the derived type.
6768 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
6770 -- The implicit_base should be frozen when the derived type is frozen,
6771 -- but note that it is used in the conversions of the bounds. For fixed
6772 -- types we delay the determination of the bounds until the proper
6773 -- freezing point. For other numeric types this is rejected by GCC, for
6774 -- reasons that are currently unclear (???), so we choose to freeze the
6775 -- implicit base now. In the case of integers and floating point types
6776 -- this is harmless because subsequent representation clauses cannot
6777 -- affect anything, but it is still baffling that we cannot use the
6778 -- same mechanism for all derived numeric types.
6780 -- There is a further complication: actually some representation
6781 -- clauses can affect the implicit base type. For example, attribute
6782 -- definition clauses for stream-oriented attributes need to set the
6783 -- corresponding TSS entries on the base type, and this normally
6784 -- cannot be done after the base type is frozen, so the circuitry in
6785 -- Sem_Ch13.New_Stream_Subprogram must account for this possibility
6786 -- and not use Set_TSS in this case.
6788 -- There are also consequences for the case of delayed representation
6789 -- aspects for some cases. For example, a Size aspect is delayed and
6790 -- should not be evaluated to the freeze point. This early freezing
6791 -- means that the size attribute evaluation happens too early???
6793 if Is_Fixed_Point_Type (Parent_Type) then
6794 Conditional_Delay (Implicit_Base, Parent_Type);
6796 Freeze_Before (N, Implicit_Base);
6798 end Build_Derived_Numeric_Type;
6800 --------------------------------
6801 -- Build_Derived_Private_Type --
6802 --------------------------------
6804 procedure Build_Derived_Private_Type
6806 Parent_Type : Entity_Id;
6807 Derived_Type : Entity_Id;
6808 Is_Completion : Boolean;
6809 Derive_Subps : Boolean := True)
6811 Loc : constant Source_Ptr := Sloc (N);
6812 Par_Base : constant Entity_Id := Base_Type (Parent_Type);
6813 Par_Scope : constant Entity_Id := Scope (Par_Base);
6814 Full_N : constant Node_Id := New_Copy_Tree (N);
6815 Full_Der : Entity_Id := New_Copy (Derived_Type);
6818 procedure Build_Full_Derivation;
6819 -- Build full derivation, i.e. derive from the full view
6821 procedure Copy_And_Build;
6822 -- Copy derived type declaration, replace parent with its full view,
6823 -- and build derivation
6825 ---------------------------
6826 -- Build_Full_Derivation --
6827 ---------------------------
6829 procedure Build_Full_Derivation is
6831 -- If parent scope is not open, install the declarations
6833 if not In_Open_Scopes (Par_Scope) then
6834 Install_Private_Declarations (Par_Scope);
6835 Install_Visible_Declarations (Par_Scope);
6837 Uninstall_Declarations (Par_Scope);
6839 -- If parent scope is open and in another unit, and parent has a
6840 -- completion, then the derivation is taking place in the visible
6841 -- part of a child unit. In that case retrieve the full view of
6842 -- the parent momentarily.
6844 elsif not In_Same_Source_Unit (N, Parent_Type) then
6845 Full_P := Full_View (Parent_Type);
6846 Exchange_Declarations (Parent_Type);
6848 Exchange_Declarations (Full_P);
6850 -- Otherwise it is a local derivation
6855 end Build_Full_Derivation;
6857 --------------------
6858 -- Copy_And_Build --
6859 --------------------
6861 procedure Copy_And_Build is
6862 Full_Parent : Entity_Id := Parent_Type;
6865 -- If the parent is itself derived from another private type,
6866 -- installing the private declarations has not affected its
6867 -- privacy status, so use its own full view explicitly.
6869 if Is_Private_Type (Full_Parent)
6870 and then Present (Full_View (Full_Parent))
6872 Full_Parent := Full_View (Full_Parent);
6875 -- And its underlying full view if necessary
6877 if Is_Private_Type (Full_Parent)
6878 and then Present (Underlying_Full_View (Full_Parent))
6880 Full_Parent := Underlying_Full_View (Full_Parent);
6883 -- For record, access and most enumeration types, derivation from
6884 -- the full view requires a fully-fledged declaration. In the other
6885 -- cases, just use an itype.
6887 if Ekind (Full_Parent) in Record_Kind
6888 or else Ekind (Full_Parent) in Access_Kind
6890 (Ekind (Full_Parent) in Enumeration_Kind
6891 and then not Is_Standard_Character_Type (Full_Parent)
6892 and then not Is_Generic_Type (Root_Type (Full_Parent)))
6894 -- Copy and adjust declaration to provide a completion for what
6895 -- is originally a private declaration. Indicate that full view
6896 -- is internally generated.
6898 Set_Comes_From_Source (Full_N, False);
6899 Set_Comes_From_Source (Full_Der, False);
6900 Set_Parent (Full_Der, Full_N);
6901 Set_Defining_Identifier (Full_N, Full_Der);
6903 -- If there are no constraints, adjust the subtype mark
6905 if Nkind (Subtype_Indication (Type_Definition (Full_N))) /=
6906 N_Subtype_Indication
6908 Set_Subtype_Indication
6909 (Type_Definition (Full_N),
6910 New_Occurrence_Of (Full_Parent, Sloc (Full_N)));
6913 Insert_After (N, Full_N);
6915 -- Build full view of derived type from full view of parent which
6916 -- is now installed. Subprograms have been derived on the partial
6917 -- view, the completion does not derive them anew.
6919 if Ekind (Full_Parent) in Record_Kind then
6921 -- If parent type is tagged, the completion inherits the proper
6922 -- primitive operations.
6924 if Is_Tagged_Type (Parent_Type) then
6925 Build_Derived_Record_Type
6926 (Full_N, Full_Parent, Full_Der, Derive_Subps);
6928 Build_Derived_Record_Type
6929 (Full_N, Full_Parent, Full_Der, Derive_Subps => False);
6934 (Full_N, Full_Parent, Full_Der,
6935 Is_Completion => False, Derive_Subps => False);
6938 -- The full declaration has been introduced into the tree and
6939 -- processed in the step above. It should not be analyzed again
6940 -- (when encountered later in the current list of declarations)
6941 -- to prevent spurious name conflicts. The full entity remains
6944 Set_Analyzed (Full_N);
6948 Make_Defining_Identifier (Sloc (Derived_Type),
6949 Chars => Chars (Derived_Type));
6950 Set_Is_Itype (Full_Der);
6951 Set_Associated_Node_For_Itype (Full_Der, N);
6952 Set_Parent (Full_Der, N);
6954 (N, Full_Parent, Full_Der,
6955 Is_Completion => False, Derive_Subps => False);
6958 Set_Has_Private_Declaration (Full_Der);
6959 Set_Has_Private_Declaration (Derived_Type);
6961 Set_Scope (Full_Der, Scope (Derived_Type));
6962 Set_Is_First_Subtype (Full_Der, Is_First_Subtype (Derived_Type));
6963 Set_Has_Size_Clause (Full_Der, False);
6964 Set_Has_Alignment_Clause (Full_Der, False);
6965 Set_Has_Delayed_Freeze (Full_Der);
6966 Set_Is_Frozen (Full_Der, False);
6967 Set_Freeze_Node (Full_Der, Empty);
6968 Set_Depends_On_Private (Full_Der, Has_Private_Component (Full_Der));
6969 Set_Is_Public (Full_Der, Is_Public (Derived_Type));
6971 -- The convention on the base type may be set in the private part
6972 -- and not propagated to the subtype until later, so we obtain the
6973 -- convention from the base type of the parent.
6975 Set_Convention (Full_Der, Convention (Base_Type (Full_Parent)));
6978 -- Start of processing for Build_Derived_Private_Type
6981 if Is_Tagged_Type (Parent_Type) then
6982 Full_P := Full_View (Parent_Type);
6984 -- A type extension of a type with unknown discriminants is an
6985 -- indefinite type that the back-end cannot handle directly.
6986 -- We treat it as a private type, and build a completion that is
6987 -- derived from the full view of the parent, and hopefully has
6988 -- known discriminants.
6990 -- If the full view of the parent type has an underlying record view,
6991 -- use it to generate the underlying record view of this derived type
6992 -- (required for chains of derivations with unknown discriminants).
6994 -- Minor optimization: we avoid the generation of useless underlying
6995 -- record view entities if the private type declaration has unknown
6996 -- discriminants but its corresponding full view has no
6999 if Has_Unknown_Discriminants (Parent_Type)
7000 and then Present (Full_P)
7001 and then (Has_Discriminants (Full_P)
7002 or else Present (Underlying_Record_View (Full_P)))
7003 and then not In_Open_Scopes (Par_Scope)
7004 and then Expander_Active
7007 Full_Der : constant Entity_Id := Make_Temporary (Loc, 'T');
7008 New_Ext : constant Node_Id :=
7010 (Record_Extension_Part (Type_Definition (N)));
7014 Build_Derived_Record_Type
7015 (N, Parent_Type, Derived_Type, Derive_Subps);
7017 -- Build anonymous completion, as a derivation from the full
7018 -- view of the parent. This is not a completion in the usual
7019 -- sense, because the current type is not private.
7022 Make_Full_Type_Declaration (Loc,
7023 Defining_Identifier => Full_Der,
7025 Make_Derived_Type_Definition (Loc,
7026 Subtype_Indication =>
7028 (Subtype_Indication (Type_Definition (N))),
7029 Record_Extension_Part => New_Ext));
7031 -- If the parent type has an underlying record view, use it
7032 -- here to build the new underlying record view.
7034 if Present (Underlying_Record_View (Full_P)) then
7036 (Nkind (Subtype_Indication (Type_Definition (Decl)))
7038 Set_Entity (Subtype_Indication (Type_Definition (Decl)),
7039 Underlying_Record_View (Full_P));
7042 Install_Private_Declarations (Par_Scope);
7043 Install_Visible_Declarations (Par_Scope);
7044 Insert_Before (N, Decl);
7046 -- Mark entity as an underlying record view before analysis,
7047 -- to avoid generating the list of its primitive operations
7048 -- (which is not really required for this entity) and thus
7049 -- prevent spurious errors associated with missing overriding
7050 -- of abstract primitives (overridden only for Derived_Type).
7052 Set_Ekind (Full_Der, E_Record_Type);
7053 Set_Is_Underlying_Record_View (Full_Der);
7054 Set_Default_SSO (Full_Der);
7058 pragma Assert (Has_Discriminants (Full_Der)
7059 and then not Has_Unknown_Discriminants (Full_Der));
7061 Uninstall_Declarations (Par_Scope);
7063 -- Freeze the underlying record view, to prevent generation of
7064 -- useless dispatching information, which is simply shared with
7065 -- the real derived type.
7067 Set_Is_Frozen (Full_Der);
7069 -- If the derived type has access discriminants, create
7070 -- references to their anonymous types now, to prevent
7071 -- back-end problems when their first use is in generated
7072 -- bodies of primitives.
7078 E := First_Entity (Full_Der);
7080 while Present (E) loop
7081 if Ekind (E) = E_Discriminant
7082 and then Ekind (Etype (E)) = E_Anonymous_Access_Type
7084 Build_Itype_Reference (Etype (E), Decl);
7091 -- Set up links between real entity and underlying record view
7093 Set_Underlying_Record_View (Derived_Type, Base_Type (Full_Der));
7094 Set_Underlying_Record_View (Base_Type (Full_Der), Derived_Type);
7097 -- If discriminants are known, build derived record
7100 Build_Derived_Record_Type
7101 (N, Parent_Type, Derived_Type, Derive_Subps);
7106 elsif Has_Discriminants (Parent_Type) then
7108 -- Build partial view of derived type from partial view of parent.
7109 -- This must be done before building the full derivation because the
7110 -- second derivation will modify the discriminants of the first and
7111 -- the discriminants are chained with the rest of the components in
7112 -- the full derivation.
7114 Build_Derived_Record_Type
7115 (N, Parent_Type, Derived_Type, Derive_Subps);
7117 -- Build the full derivation if this is not the anonymous derived
7118 -- base type created by Build_Derived_Record_Type in the constrained
7119 -- case (see point 5. of its head comment) since we build it for the
7120 -- derived subtype. And skip it for protected types altogether, as
7121 -- gigi does not use these types directly.
7123 if Present (Full_View (Parent_Type))
7124 and then not Is_Itype (Derived_Type)
7125 and then not (Ekind (Full_View (Parent_Type)) in Protected_Kind)
7128 Der_Base : constant Entity_Id := Base_Type (Derived_Type);
7130 Last_Discr : Entity_Id;
7133 -- If this is not a completion, construct the implicit full
7134 -- view by deriving from the full view of the parent type.
7135 -- But if this is a completion, the derived private type
7136 -- being built is a full view and the full derivation can
7137 -- only be its underlying full view.
7139 Build_Full_Derivation;
7141 if not Is_Completion then
7142 Set_Full_View (Derived_Type, Full_Der);
7144 Set_Underlying_Full_View (Derived_Type, Full_Der);
7147 if not Is_Base_Type (Derived_Type) then
7148 Set_Full_View (Der_Base, Base_Type (Full_Der));
7151 -- Copy the discriminant list from full view to the partial
7152 -- view (base type and its subtype). Gigi requires that the
7153 -- partial and full views have the same discriminants.
7155 -- Note that since the partial view points to discriminants
7156 -- in the full view, their scope will be that of the full
7157 -- view. This might cause some front end problems and need
7160 Discr := First_Discriminant (Base_Type (Full_Der));
7161 Set_First_Entity (Der_Base, Discr);
7164 Last_Discr := Discr;
7165 Next_Discriminant (Discr);
7166 exit when No (Discr);
7169 Set_Last_Entity (Der_Base, Last_Discr);
7170 Set_First_Entity (Derived_Type, First_Entity (Der_Base));
7171 Set_Last_Entity (Derived_Type, Last_Entity (Der_Base));
7173 Set_Stored_Constraint
7174 (Full_Der, Stored_Constraint (Derived_Type));
7178 elsif Present (Full_View (Parent_Type))
7179 and then Has_Discriminants (Full_View (Parent_Type))
7181 if Has_Unknown_Discriminants (Parent_Type)
7182 and then Nkind (Subtype_Indication (Type_Definition (N))) =
7183 N_Subtype_Indication
7186 ("cannot constrain type with unknown discriminants",
7187 Subtype_Indication (Type_Definition (N)));
7191 -- If this is not a completion, construct the implicit full view by
7192 -- deriving from the full view of the parent type. But if this is a
7193 -- completion, the derived private type being built is a full view
7194 -- and the full derivation can only be its underlying full view.
7196 Build_Full_Derivation;
7198 if not Is_Completion then
7199 Set_Full_View (Derived_Type, Full_Der);
7201 Set_Underlying_Full_View (Derived_Type, Full_Der);
7204 -- In any case, the primitive operations are inherited from the
7205 -- parent type, not from the internal full view.
7207 Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type));
7209 if Derive_Subps then
7210 Derive_Subprograms (Parent_Type, Derived_Type);
7213 Set_Stored_Constraint (Derived_Type, No_Elist);
7215 (Derived_Type, Is_Constrained (Full_View (Parent_Type)));
7218 -- Untagged type, No discriminants on either view
7220 if Nkind (Subtype_Indication (Type_Definition (N))) =
7221 N_Subtype_Indication
7224 ("illegal constraint on type without discriminants", N);
7227 if Present (Discriminant_Specifications (N))
7228 and then Present (Full_View (Parent_Type))
7229 and then not Is_Tagged_Type (Full_View (Parent_Type))
7231 Error_Msg_N ("cannot add discriminants to untagged type", N);
7234 Set_Stored_Constraint (Derived_Type, No_Elist);
7235 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
7236 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
7237 Set_Has_Controlled_Component
7238 (Derived_Type, Has_Controlled_Component
7241 -- Direct controlled types do not inherit Finalize_Storage_Only flag
7243 if not Is_Controlled (Parent_Type) then
7244 Set_Finalize_Storage_Only
7245 (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type));
7248 -- If this is not a completion, construct the implicit full view by
7249 -- deriving from the full view of the parent type.
7251 -- ??? If the parent is untagged private and its completion is
7252 -- tagged, this mechanism will not work because we cannot derive from
7253 -- the tagged full view unless we have an extension.
7255 if Present (Full_View (Parent_Type))
7256 and then not Is_Tagged_Type (Full_View (Parent_Type))
7257 and then not Is_Completion
7259 Build_Full_Derivation;
7260 Set_Full_View (Derived_Type, Full_Der);
7264 Set_Has_Unknown_Discriminants (Derived_Type,
7265 Has_Unknown_Discriminants (Parent_Type));
7267 if Is_Private_Type (Derived_Type) then
7268 Set_Private_Dependents (Derived_Type, New_Elmt_List);
7271 -- If the parent base type is in scope, add the derived type to its
7272 -- list of private dependents, because its full view may become
7273 -- visible subsequently (in a nested private part, a body, or in a
7274 -- further child unit).
7276 if Is_Private_Type (Par_Base) and then In_Open_Scopes (Par_Scope) then
7277 Append_Elmt (Derived_Type, Private_Dependents (Parent_Type));
7279 -- Check for unusual case where a type completed by a private
7280 -- derivation occurs within a package nested in a child unit, and
7281 -- the parent is declared in an ancestor.
7283 if Is_Child_Unit (Scope (Current_Scope))
7284 and then Is_Completion
7285 and then In_Private_Part (Current_Scope)
7286 and then Scope (Parent_Type) /= Current_Scope
7288 -- Note that if the parent has a completion in the private part,
7289 -- (which is itself a derivation from some other private type)
7290 -- it is that completion that is visible, there is no full view
7291 -- available, and no special processing is needed.
7293 and then Present (Full_View (Parent_Type))
7295 -- In this case, the full view of the parent type will become
7296 -- visible in the body of the enclosing child, and only then will
7297 -- the current type be possibly non-private. Build an underlying
7298 -- full view that will be installed when the enclosing child body
7301 if Present (Underlying_Full_View (Derived_Type)) then
7302 Full_Der := Underlying_Full_View (Derived_Type);
7304 Build_Full_Derivation;
7305 Set_Underlying_Full_View (Derived_Type, Full_Der);
7308 -- The full view will be used to swap entities on entry/exit to
7309 -- the body, and must appear in the entity list for the package.
7311 Append_Entity (Full_Der, Scope (Derived_Type));
7314 end Build_Derived_Private_Type;
7316 -------------------------------
7317 -- Build_Derived_Record_Type --
7318 -------------------------------
7322 -- Ideally we would like to use the same model of type derivation for
7323 -- tagged and untagged record types. Unfortunately this is not quite
7324 -- possible because the semantics of representation clauses is different
7325 -- for tagged and untagged records under inheritance. Consider the
7328 -- type R (...) is [tagged] record ... end record;
7329 -- type T (...) is new R (...) [with ...];
7331 -- The representation clauses for T can specify a completely different
7332 -- record layout from R's. Hence the same component can be placed in two
7333 -- very different positions in objects of type T and R. If R and T are
7334 -- tagged types, representation clauses for T can only specify the layout
7335 -- of non inherited components, thus components that are common in R and T
7336 -- have the same position in objects of type R and T.
7338 -- This has two implications. The first is that the entire tree for R's
7339 -- declaration needs to be copied for T in the untagged case, so that T
7340 -- can be viewed as a record type of its own with its own representation
7341 -- clauses. The second implication is the way we handle discriminants.
7342 -- Specifically, in the untagged case we need a way to communicate to Gigi
7343 -- what are the real discriminants in the record, while for the semantics
7344 -- we need to consider those introduced by the user to rename the
7345 -- discriminants in the parent type. This is handled by introducing the
7346 -- notion of stored discriminants. See below for more.
7348 -- Fortunately the way regular components are inherited can be handled in
7349 -- the same way in tagged and untagged types.
7351 -- To complicate things a bit more the private view of a private extension
7352 -- cannot be handled in the same way as the full view (for one thing the
7353 -- semantic rules are somewhat different). We will explain what differs
7356 -- 2. DISCRIMINANTS UNDER INHERITANCE
7358 -- The semantic rules governing the discriminants of derived types are
7361 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
7362 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
7364 -- If parent type has discriminants, then the discriminants that are
7365 -- declared in the derived type are [3.4 (11)]:
7367 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
7370 -- o Otherwise, each discriminant of the parent type (implicitly declared
7371 -- in the same order with the same specifications). In this case, the
7372 -- discriminants are said to be "inherited", or if unknown in the parent
7373 -- are also unknown in the derived type.
7375 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
7377 -- o The parent subtype must be constrained;
7379 -- o If the parent type is not a tagged type, then each discriminant of
7380 -- the derived type must be used in the constraint defining a parent
7381 -- subtype. [Implementation note: This ensures that the new discriminant
7382 -- can share storage with an existing discriminant.]
7384 -- For the derived type each discriminant of the parent type is either
7385 -- inherited, constrained to equal some new discriminant of the derived
7386 -- type, or constrained to the value of an expression.
7388 -- When inherited or constrained to equal some new discriminant, the
7389 -- parent discriminant and the discriminant of the derived type are said
7392 -- If a discriminant of the parent type is constrained to a specific value
7393 -- in the derived type definition, then the discriminant is said to be
7394 -- "specified" by that derived type definition.
7396 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES
7398 -- We have spoken about stored discriminants in point 1 (introduction)
7399 -- above. There are two sort of stored discriminants: implicit and
7400 -- explicit. As long as the derived type inherits the same discriminants as
7401 -- the root record type, stored discriminants are the same as regular
7402 -- discriminants, and are said to be implicit. However, if any discriminant
7403 -- in the root type was renamed in the derived type, then the derived
7404 -- type will contain explicit stored discriminants. Explicit stored
7405 -- discriminants are discriminants in addition to the semantically visible
7406 -- discriminants defined for the derived type. Stored discriminants are
7407 -- used by Gigi to figure out what are the physical discriminants in
7408 -- objects of the derived type (see precise definition in einfo.ads).
7409 -- As an example, consider the following:
7411 -- type R (D1, D2, D3 : Int) is record ... end record;
7412 -- type T1 is new R;
7413 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
7414 -- type T3 is new T2;
7415 -- type T4 (Y : Int) is new T3 (Y, 99);
7417 -- The following table summarizes the discriminants and stored
7418 -- discriminants in R and T1 through T4.
7420 -- Type Discrim Stored Discrim Comment
7421 -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R
7422 -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1
7423 -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2
7424 -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3
7425 -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4
7427 -- Field Corresponding_Discriminant (abbreviated CD below) allows us to
7428 -- find the corresponding discriminant in the parent type, while
7429 -- Original_Record_Component (abbreviated ORC below), the actual physical
7430 -- component that is renamed. Finally the field Is_Completely_Hidden
7431 -- (abbreviated ICH below) is set for all explicit stored discriminants
7432 -- (see einfo.ads for more info). For the above example this gives:
7434 -- Discrim CD ORC ICH
7435 -- ^^^^^^^ ^^ ^^^ ^^^
7436 -- D1 in R empty itself no
7437 -- D2 in R empty itself no
7438 -- D3 in R empty itself no
7440 -- D1 in T1 D1 in R itself no
7441 -- D2 in T1 D2 in R itself no
7442 -- D3 in T1 D3 in R itself no
7444 -- X1 in T2 D3 in T1 D3 in T2 no
7445 -- X2 in T2 D1 in T1 D1 in T2 no
7446 -- D1 in T2 empty itself yes
7447 -- D2 in T2 empty itself yes
7448 -- D3 in T2 empty itself yes
7450 -- X1 in T3 X1 in T2 D3 in T3 no
7451 -- X2 in T3 X2 in T2 D1 in T3 no
7452 -- D1 in T3 empty itself yes
7453 -- D2 in T3 empty itself yes
7454 -- D3 in T3 empty itself yes
7456 -- Y in T4 X1 in T3 D3 in T3 no
7457 -- D1 in T3 empty itself yes
7458 -- D2 in T3 empty itself yes
7459 -- D3 in T3 empty itself yes
7461 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES
7463 -- Type derivation for tagged types is fairly straightforward. If no
7464 -- discriminants are specified by the derived type, these are inherited
7465 -- from the parent. No explicit stored discriminants are ever necessary.
7466 -- The only manipulation that is done to the tree is that of adding a
7467 -- _parent field with parent type and constrained to the same constraint
7468 -- specified for the parent in the derived type definition. For instance:
7470 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
7471 -- type T1 is new R with null record;
7472 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
7474 -- are changed into:
7476 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
7477 -- _parent : R (D1, D2, D3);
7480 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
7481 -- _parent : T1 (X2, 88, X1);
7484 -- The discriminants actually present in R, T1 and T2 as well as their CD,
7485 -- ORC and ICH fields are:
7487 -- Discrim CD ORC ICH
7488 -- ^^^^^^^ ^^ ^^^ ^^^
7489 -- D1 in R empty itself no
7490 -- D2 in R empty itself no
7491 -- D3 in R empty itself no
7493 -- D1 in T1 D1 in R D1 in R no
7494 -- D2 in T1 D2 in R D2 in R no
7495 -- D3 in T1 D3 in R D3 in R no
7497 -- X1 in T2 D3 in T1 D3 in R no
7498 -- X2 in T2 D1 in T1 D1 in R no
7500 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS
7502 -- Regardless of whether we dealing with a tagged or untagged type
7503 -- we will transform all derived type declarations of the form
7505 -- type T is new R (...) [with ...];
7507 -- subtype S is R (...);
7508 -- type T is new S [with ...];
7510 -- type BT is new R [with ...];
7511 -- subtype T is BT (...);
7513 -- That is, the base derived type is constrained only if it has no
7514 -- discriminants. The reason for doing this is that GNAT's semantic model
7515 -- assumes that a base type with discriminants is unconstrained.
7517 -- Note that, strictly speaking, the above transformation is not always
7518 -- correct. Consider for instance the following excerpt from ACVC b34011a:
7520 -- procedure B34011A is
7521 -- type REC (D : integer := 0) is record
7526 -- type T6 is new Rec;
7527 -- function F return T6;
7532 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
7535 -- The definition of Q6.U is illegal. However transforming Q6.U into
7537 -- type BaseU is new T6;
7538 -- subtype U is BaseU (Q6.F.I)
7540 -- turns U into a legal subtype, which is incorrect. To avoid this problem
7541 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
7542 -- the transformation described above.
7544 -- There is another instance where the above transformation is incorrect.
7548 -- type Base (D : Integer) is tagged null record;
7549 -- procedure P (X : Base);
7551 -- type Der is new Base (2) with null record;
7552 -- procedure P (X : Der);
7555 -- Then the above transformation turns this into
7557 -- type Der_Base is new Base with null record;
7558 -- -- procedure P (X : Base) is implicitly inherited here
7559 -- -- as procedure P (X : Der_Base).
7561 -- subtype Der is Der_Base (2);
7562 -- procedure P (X : Der);
7563 -- -- The overriding of P (X : Der_Base) is illegal since we
7564 -- -- have a parameter conformance problem.
7566 -- To get around this problem, after having semantically processed Der_Base
7567 -- and the rewritten subtype declaration for Der, we copy Der_Base field
7568 -- Discriminant_Constraint from Der so that when parameter conformance is
7569 -- checked when P is overridden, no semantic errors are flagged.
7571 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS
7573 -- Regardless of whether we are dealing with a tagged or untagged type
7574 -- we will transform all derived type declarations of the form
7576 -- type R (D1, .., Dn : ...) is [tagged] record ...;
7577 -- type T is new R [with ...];
7579 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
7581 -- The reason for such transformation is that it allows us to implement a
7582 -- very clean form of component inheritance as explained below.
7584 -- Note that this transformation is not achieved by direct tree rewriting
7585 -- and manipulation, but rather by redoing the semantic actions that the
7586 -- above transformation will entail. This is done directly in routine
7587 -- Inherit_Components.
7589 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE
7591 -- In both tagged and untagged derived types, regular non discriminant
7592 -- components are inherited in the derived type from the parent type. In
7593 -- the absence of discriminants component, inheritance is straightforward
7594 -- as components can simply be copied from the parent.
7596 -- If the parent has discriminants, inheriting components constrained with
7597 -- these discriminants requires caution. Consider the following example:
7599 -- type R (D1, D2 : Positive) is [tagged] record
7600 -- S : String (D1 .. D2);
7603 -- type T1 is new R [with null record];
7604 -- type T2 (X : positive) is new R (1, X) [with null record];
7606 -- As explained in 6. above, T1 is rewritten as
7607 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
7608 -- which makes the treatment for T1 and T2 identical.
7610 -- What we want when inheriting S, is that references to D1 and D2 in R are
7611 -- replaced with references to their correct constraints, i.e. D1 and D2 in
7612 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
7613 -- with either discriminant references in the derived type or expressions.
7614 -- This replacement is achieved as follows: before inheriting R's
7615 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
7616 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
7617 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
7618 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
7619 -- by String (1 .. X).
7621 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS
7623 -- We explain here the rules governing private type extensions relevant to
7624 -- type derivation. These rules are explained on the following example:
7626 -- type D [(...)] is new A [(...)] with private; <-- partial view
7627 -- type D [(...)] is new P [(...)] with null record; <-- full view
7629 -- Type A is called the ancestor subtype of the private extension.
7630 -- Type P is the parent type of the full view of the private extension. It
7631 -- must be A or a type derived from A.
7633 -- The rules concerning the discriminants of private type extensions are
7636 -- o If a private extension inherits known discriminants from the ancestor
7637 -- subtype, then the full view must also inherit its discriminants from
7638 -- the ancestor subtype and the parent subtype of the full view must be
7639 -- constrained if and only if the ancestor subtype is constrained.
7641 -- o If a partial view has unknown discriminants, then the full view may
7642 -- define a definite or an indefinite subtype, with or without
7645 -- o If a partial view has neither known nor unknown discriminants, then
7646 -- the full view must define a definite subtype.
7648 -- o If the ancestor subtype of a private extension has constrained
7649 -- discriminants, then the parent subtype of the full view must impose a
7650 -- statically matching constraint on those discriminants.
7652 -- This means that only the following forms of private extensions are
7655 -- type D is new A with private; <-- partial view
7656 -- type D is new P with null record; <-- full view
7658 -- If A has no discriminants than P has no discriminants, otherwise P must
7659 -- inherit A's discriminants.
7661 -- type D is new A (...) with private; <-- partial view
7662 -- type D is new P (:::) with null record; <-- full view
7664 -- P must inherit A's discriminants and (...) and (:::) must statically
7667 -- subtype A is R (...);
7668 -- type D is new A with private; <-- partial view
7669 -- type D is new P with null record; <-- full view
7671 -- P must have inherited R's discriminants and must be derived from A or
7672 -- any of its subtypes.
7674 -- type D (..) is new A with private; <-- partial view
7675 -- type D (..) is new P [(:::)] with null record; <-- full view
7677 -- No specific constraints on P's discriminants or constraint (:::).
7678 -- Note that A can be unconstrained, but the parent subtype P must either
7679 -- be constrained or (:::) must be present.
7681 -- type D (..) is new A [(...)] with private; <-- partial view
7682 -- type D (..) is new P [(:::)] with null record; <-- full view
7684 -- P's constraints on A's discriminants must statically match those
7685 -- imposed by (...).
7687 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS
7689 -- The full view of a private extension is handled exactly as described
7690 -- above. The model chose for the private view of a private extension is
7691 -- the same for what concerns discriminants (i.e. they receive the same
7692 -- treatment as in the tagged case). However, the private view of the
7693 -- private extension always inherits the components of the parent base,
7694 -- without replacing any discriminant reference. Strictly speaking this is
7695 -- incorrect. However, Gigi never uses this view to generate code so this
7696 -- is a purely semantic issue. In theory, a set of transformations similar
7697 -- to those given in 5. and 6. above could be applied to private views of
7698 -- private extensions to have the same model of component inheritance as
7699 -- for non private extensions. However, this is not done because it would
7700 -- further complicate private type processing. Semantically speaking, this
7701 -- leaves us in an uncomfortable situation. As an example consider:
7704 -- type R (D : integer) is tagged record
7705 -- S : String (1 .. D);
7707 -- procedure P (X : R);
7708 -- type T is new R (1) with private;
7710 -- type T is new R (1) with null record;
7713 -- This is transformed into:
7716 -- type R (D : integer) is tagged record
7717 -- S : String (1 .. D);
7719 -- procedure P (X : R);
7720 -- type T is new R (1) with private;
7722 -- type BaseT is new R with null record;
7723 -- subtype T is BaseT (1);
7726 -- (strictly speaking the above is incorrect Ada)
7728 -- From the semantic standpoint the private view of private extension T
7729 -- should be flagged as constrained since one can clearly have
7733 -- in a unit withing Pack. However, when deriving subprograms for the
7734 -- private view of private extension T, T must be seen as unconstrained
7735 -- since T has discriminants (this is a constraint of the current
7736 -- subprogram derivation model). Thus, when processing the private view of
7737 -- a private extension such as T, we first mark T as unconstrained, we
7738 -- process it, we perform program derivation and just before returning from
7739 -- Build_Derived_Record_Type we mark T as constrained.
7741 -- ??? Are there are other uncomfortable cases that we will have to
7744 -- 10. RECORD_TYPE_WITH_PRIVATE complications
7746 -- Types that are derived from a visible record type and have a private
7747 -- extension present other peculiarities. They behave mostly like private
7748 -- types, but if they have primitive operations defined, these will not
7749 -- have the proper signatures for further inheritance, because other
7750 -- primitive operations will use the implicit base that we define for
7751 -- private derivations below. This affect subprogram inheritance (see
7752 -- Derive_Subprograms for details). We also derive the implicit base from
7753 -- the base type of the full view, so that the implicit base is a record
7754 -- type and not another private type, This avoids infinite loops.
7756 procedure Build_Derived_Record_Type
7758 Parent_Type : Entity_Id;
7759 Derived_Type : Entity_Id;
7760 Derive_Subps : Boolean := True)
7762 Discriminant_Specs : constant Boolean :=
7763 Present (Discriminant_Specifications (N));
7764 Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type);
7765 Loc : constant Source_Ptr := Sloc (N);
7766 Private_Extension : constant Boolean :=
7767 Nkind (N) = N_Private_Extension_Declaration;
7768 Assoc_List : Elist_Id;
7769 Constraint_Present : Boolean;
7771 Discrim : Entity_Id;
7773 Inherit_Discrims : Boolean := False;
7774 Last_Discrim : Entity_Id;
7775 New_Base : Entity_Id;
7777 New_Discrs : Elist_Id;
7778 New_Indic : Node_Id;
7779 Parent_Base : Entity_Id;
7780 Save_Etype : Entity_Id;
7781 Save_Discr_Constr : Elist_Id;
7782 Save_Next_Entity : Entity_Id;
7785 Discs : Elist_Id := New_Elmt_List;
7786 -- An empty Discs list means that there were no constraints in the
7787 -- subtype indication or that there was an error processing it.
7790 if Ekind (Parent_Type) = E_Record_Type_With_Private
7791 and then Present (Full_View (Parent_Type))
7792 and then Has_Discriminants (Parent_Type)
7794 Parent_Base := Base_Type (Full_View (Parent_Type));
7796 Parent_Base := Base_Type (Parent_Type);
7799 -- AI05-0115 : if this is a derivation from a private type in some
7800 -- other scope that may lead to invisible components for the derived
7801 -- type, mark it accordingly.
7803 if Is_Private_Type (Parent_Type) then
7804 if Scope (Parent_Type) = Scope (Derived_Type) then
7807 elsif In_Open_Scopes (Scope (Parent_Type))
7808 and then In_Private_Part (Scope (Parent_Type))
7813 Set_Has_Private_Ancestor (Derived_Type);
7817 Set_Has_Private_Ancestor
7818 (Derived_Type, Has_Private_Ancestor (Parent_Type));
7821 -- Before we start the previously documented transformations, here is
7822 -- little fix for size and alignment of tagged types. Normally when we
7823 -- derive type D from type P, we copy the size and alignment of P as the
7824 -- default for D, and in the absence of explicit representation clauses
7825 -- for D, the size and alignment are indeed the same as the parent.
7827 -- But this is wrong for tagged types, since fields may be added, and
7828 -- the default size may need to be larger, and the default alignment may
7829 -- need to be larger.
7831 -- We therefore reset the size and alignment fields in the tagged case.
7832 -- Note that the size and alignment will in any case be at least as
7833 -- large as the parent type (since the derived type has a copy of the
7834 -- parent type in the _parent field)
7836 -- The type is also marked as being tagged here, which is needed when
7837 -- processing components with a self-referential anonymous access type
7838 -- in the call to Check_Anonymous_Access_Components below. Note that
7839 -- this flag is also set later on for completeness.
7842 Set_Is_Tagged_Type (Derived_Type);
7843 Init_Size_Align (Derived_Type);
7846 -- STEP 0a: figure out what kind of derived type declaration we have
7848 if Private_Extension then
7850 Set_Ekind (Derived_Type, E_Record_Type_With_Private);
7851 Set_Default_SSO (Derived_Type);
7854 Type_Def := Type_Definition (N);
7856 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
7857 -- Parent_Base can be a private type or private extension. However,
7858 -- for tagged types with an extension the newly added fields are
7859 -- visible and hence the Derived_Type is always an E_Record_Type.
7860 -- (except that the parent may have its own private fields).
7861 -- For untagged types we preserve the Ekind of the Parent_Base.
7863 if Present (Record_Extension_Part (Type_Def)) then
7864 Set_Ekind (Derived_Type, E_Record_Type);
7865 Set_Default_SSO (Derived_Type);
7867 -- Create internal access types for components with anonymous
7870 if Ada_Version >= Ada_2005 then
7871 Check_Anonymous_Access_Components
7872 (N, Derived_Type, Derived_Type,
7873 Component_List (Record_Extension_Part (Type_Def)));
7877 Set_Ekind (Derived_Type, Ekind (Parent_Base));
7881 -- Indic can either be an N_Identifier if the subtype indication
7882 -- contains no constraint or an N_Subtype_Indication if the subtype
7883 -- indication has a constraint.
7885 Indic := Subtype_Indication (Type_Def);
7886 Constraint_Present := (Nkind (Indic) = N_Subtype_Indication);
7888 -- Check that the type has visible discriminants. The type may be
7889 -- a private type with unknown discriminants whose full view has
7890 -- discriminants which are invisible.
7892 if Constraint_Present then
7893 if not Has_Discriminants (Parent_Base)
7895 (Has_Unknown_Discriminants (Parent_Base)
7896 and then Is_Private_Type (Parent_Base))
7899 ("invalid constraint: type has no discriminant",
7900 Constraint (Indic));
7902 Constraint_Present := False;
7903 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7905 elsif Is_Constrained (Parent_Type) then
7907 ("invalid constraint: parent type is already constrained",
7908 Constraint (Indic));
7910 Constraint_Present := False;
7911 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7915 -- STEP 0b: If needed, apply transformation given in point 5. above
7917 if not Private_Extension
7918 and then Has_Discriminants (Parent_Type)
7919 and then not Discriminant_Specs
7920 and then (Is_Constrained (Parent_Type) or else Constraint_Present)
7922 -- First, we must analyze the constraint (see comment in point 5.)
7923 -- The constraint may come from the subtype indication of the full
7926 if Constraint_Present then
7927 New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic);
7929 -- If there is no explicit constraint, there might be one that is
7930 -- inherited from a constrained parent type. In that case verify that
7931 -- it conforms to the constraint in the partial view. In perverse
7932 -- cases the parent subtypes of the partial and full view can have
7933 -- different constraints.
7935 elsif Present (Stored_Constraint (Parent_Type)) then
7936 New_Discrs := Stored_Constraint (Parent_Type);
7939 New_Discrs := No_Elist;
7942 if Has_Discriminants (Derived_Type)
7943 and then Has_Private_Declaration (Derived_Type)
7944 and then Present (Discriminant_Constraint (Derived_Type))
7945 and then Present (New_Discrs)
7947 -- Verify that constraints of the full view statically match
7948 -- those given in the partial view.
7954 C1 := First_Elmt (New_Discrs);
7955 C2 := First_Elmt (Discriminant_Constraint (Derived_Type));
7956 while Present (C1) and then Present (C2) loop
7957 if Fully_Conformant_Expressions (Node (C1), Node (C2))
7959 (Is_OK_Static_Expression (Node (C1))
7960 and then Is_OK_Static_Expression (Node (C2))
7962 Expr_Value (Node (C1)) = Expr_Value (Node (C2)))
7967 if Constraint_Present then
7969 ("constraint not conformant to previous declaration",
7973 ("constraint of full view is incompatible "
7974 & "with partial view", N);
7984 -- Insert and analyze the declaration for the unconstrained base type
7986 New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B');
7989 Make_Full_Type_Declaration (Loc,
7990 Defining_Identifier => New_Base,
7992 Make_Derived_Type_Definition (Loc,
7993 Abstract_Present => Abstract_Present (Type_Def),
7994 Limited_Present => Limited_Present (Type_Def),
7995 Subtype_Indication =>
7996 New_Occurrence_Of (Parent_Base, Loc),
7997 Record_Extension_Part =>
7998 Relocate_Node (Record_Extension_Part (Type_Def)),
7999 Interface_List => Interface_List (Type_Def)));
8001 Set_Parent (New_Decl, Parent (N));
8002 Mark_Rewrite_Insertion (New_Decl);
8003 Insert_Before (N, New_Decl);
8005 -- In the extension case, make sure ancestor is frozen appropriately
8006 -- (see also non-discriminated case below).
8008 if Present (Record_Extension_Part (Type_Def))
8009 or else Is_Interface (Parent_Base)
8011 Freeze_Before (New_Decl, Parent_Type);
8014 -- Note that this call passes False for the Derive_Subps parameter
8015 -- because subprogram derivation is deferred until after creating
8016 -- the subtype (see below).
8019 (New_Decl, Parent_Base, New_Base,
8020 Is_Completion => False, Derive_Subps => False);
8022 -- ??? This needs re-examination to determine whether the
8023 -- above call can simply be replaced by a call to Analyze.
8025 Set_Analyzed (New_Decl);
8027 -- Insert and analyze the declaration for the constrained subtype
8029 if Constraint_Present then
8031 Make_Subtype_Indication (Loc,
8032 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8033 Constraint => Relocate_Node (Constraint (Indic)));
8037 Constr_List : constant List_Id := New_List;
8042 C := First_Elmt (Discriminant_Constraint (Parent_Type));
8043 while Present (C) loop
8046 -- It is safe here to call New_Copy_Tree since
8047 -- Force_Evaluation was called on each constraint in
8048 -- Build_Discriminant_Constraints.
8050 Append (New_Copy_Tree (Expr), To => Constr_List);
8056 Make_Subtype_Indication (Loc,
8057 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8059 Make_Index_Or_Discriminant_Constraint (Loc, Constr_List));
8064 Make_Subtype_Declaration (Loc,
8065 Defining_Identifier => Derived_Type,
8066 Subtype_Indication => New_Indic));
8070 -- Derivation of subprograms must be delayed until the full subtype
8071 -- has been established, to ensure proper overriding of subprograms
8072 -- inherited by full types. If the derivations occurred as part of
8073 -- the call to Build_Derived_Type above, then the check for type
8074 -- conformance would fail because earlier primitive subprograms
8075 -- could still refer to the full type prior the change to the new
8076 -- subtype and hence would not match the new base type created here.
8077 -- Subprograms are not derived, however, when Derive_Subps is False
8078 -- (since otherwise there could be redundant derivations).
8080 if Derive_Subps then
8081 Derive_Subprograms (Parent_Type, Derived_Type);
8084 -- For tagged types the Discriminant_Constraint of the new base itype
8085 -- is inherited from the first subtype so that no subtype conformance
8086 -- problem arise when the first subtype overrides primitive
8087 -- operations inherited by the implicit base type.
8090 Set_Discriminant_Constraint
8091 (New_Base, Discriminant_Constraint (Derived_Type));
8097 -- If we get here Derived_Type will have no discriminants or it will be
8098 -- a discriminated unconstrained base type.
8100 -- STEP 1a: perform preliminary actions/checks for derived tagged types
8104 -- The parent type is frozen for non-private extensions (RM 13.14(7))
8105 -- The declaration of a specific descendant of an interface type
8106 -- freezes the interface type (RM 13.14).
8108 if not Private_Extension or else Is_Interface (Parent_Base) then
8109 Freeze_Before (N, Parent_Type);
8112 -- In Ada 2005 (AI-344), the restriction that a derived tagged type
8113 -- cannot be declared at a deeper level than its parent type is
8114 -- removed. The check on derivation within a generic body is also
8115 -- relaxed, but there's a restriction that a derived tagged type
8116 -- cannot be declared in a generic body if it's derived directly
8117 -- or indirectly from a formal type of that generic.
8119 if Ada_Version >= Ada_2005 then
8120 if Present (Enclosing_Generic_Body (Derived_Type)) then
8122 Ancestor_Type : Entity_Id;
8125 -- Check to see if any ancestor of the derived type is a
8128 Ancestor_Type := Parent_Type;
8129 while not Is_Generic_Type (Ancestor_Type)
8130 and then Etype (Ancestor_Type) /= Ancestor_Type
8132 Ancestor_Type := Etype (Ancestor_Type);
8135 -- If the derived type does have a formal type as an
8136 -- ancestor, then it's an error if the derived type is
8137 -- declared within the body of the generic unit that
8138 -- declares the formal type in its generic formal part. It's
8139 -- sufficient to check whether the ancestor type is declared
8140 -- inside the same generic body as the derived type (such as
8141 -- within a nested generic spec), in which case the
8142 -- derivation is legal. If the formal type is declared
8143 -- outside of that generic body, then it's guaranteed that
8144 -- the derived type is declared within the generic body of
8145 -- the generic unit declaring the formal type.
8147 if Is_Generic_Type (Ancestor_Type)
8148 and then Enclosing_Generic_Body (Ancestor_Type) /=
8149 Enclosing_Generic_Body (Derived_Type)
8152 ("parent type of& must not be descendant of formal type"
8153 & " of an enclosing generic body",
8154 Indic, Derived_Type);
8159 elsif Type_Access_Level (Derived_Type) /=
8160 Type_Access_Level (Parent_Type)
8161 and then not Is_Generic_Type (Derived_Type)
8163 if Is_Controlled (Parent_Type) then
8165 ("controlled type must be declared at the library level",
8169 ("type extension at deeper accessibility level than parent",
8175 GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type);
8178 and then GB /= Enclosing_Generic_Body (Parent_Base)
8181 ("parent type of& must not be outside generic body"
8183 Indic, Derived_Type);
8189 -- Ada 2005 (AI-251)
8191 if Ada_Version >= Ada_2005 and then Is_Tagged then
8193 -- "The declaration of a specific descendant of an interface type
8194 -- freezes the interface type" (RM 13.14).
8199 if Is_Non_Empty_List (Interface_List (Type_Def)) then
8200 Iface := First (Interface_List (Type_Def));
8201 while Present (Iface) loop
8202 Freeze_Before (N, Etype (Iface));
8209 -- STEP 1b : preliminary cleanup of the full view of private types
8211 -- If the type is already marked as having discriminants, then it's the
8212 -- completion of a private type or private extension and we need to
8213 -- retain the discriminants from the partial view if the current
8214 -- declaration has Discriminant_Specifications so that we can verify
8215 -- conformance. However, we must remove any existing components that
8216 -- were inherited from the parent (and attached in Copy_And_Swap)
8217 -- because the full type inherits all appropriate components anyway, and
8218 -- we do not want the partial view's components interfering.
8220 if Has_Discriminants (Derived_Type) and then Discriminant_Specs then
8221 Discrim := First_Discriminant (Derived_Type);
8223 Last_Discrim := Discrim;
8224 Next_Discriminant (Discrim);
8225 exit when No (Discrim);
8228 Set_Last_Entity (Derived_Type, Last_Discrim);
8230 -- In all other cases wipe out the list of inherited components (even
8231 -- inherited discriminants), it will be properly rebuilt here.
8234 Set_First_Entity (Derived_Type, Empty);
8235 Set_Last_Entity (Derived_Type, Empty);
8238 -- STEP 1c: Initialize some flags for the Derived_Type
8240 -- The following flags must be initialized here so that
8241 -- Process_Discriminants can check that discriminants of tagged types do
8242 -- not have a default initial value and that access discriminants are
8243 -- only specified for limited records. For completeness, these flags are
8244 -- also initialized along with all the other flags below.
8246 -- AI-419: Limitedness is not inherited from an interface parent, so to
8247 -- be limited in that case the type must be explicitly declared as
8248 -- limited. However, task and protected interfaces are always limited.
8250 if Limited_Present (Type_Def) then
8251 Set_Is_Limited_Record (Derived_Type);
8253 elsif Is_Limited_Record (Parent_Type)
8254 or else (Present (Full_View (Parent_Type))
8255 and then Is_Limited_Record (Full_View (Parent_Type)))
8257 if not Is_Interface (Parent_Type)
8258 or else Is_Synchronized_Interface (Parent_Type)
8259 or else Is_Protected_Interface (Parent_Type)
8260 or else Is_Task_Interface (Parent_Type)
8262 Set_Is_Limited_Record (Derived_Type);
8266 -- STEP 2a: process discriminants of derived type if any
8268 Push_Scope (Derived_Type);
8270 if Discriminant_Specs then
8271 Set_Has_Unknown_Discriminants (Derived_Type, False);
8273 -- The following call initializes fields Has_Discriminants and
8274 -- Discriminant_Constraint, unless we are processing the completion
8275 -- of a private type declaration.
8277 Check_Or_Process_Discriminants (N, Derived_Type);
8279 -- For untagged types, the constraint on the Parent_Type must be
8280 -- present and is used to rename the discriminants.
8282 if not Is_Tagged and then not Has_Discriminants (Parent_Type) then
8283 Error_Msg_N ("untagged parent must have discriminants", Indic);
8285 elsif not Is_Tagged and then not Constraint_Present then
8287 ("discriminant constraint needed for derived untagged records",
8290 -- Otherwise the parent subtype must be constrained unless we have a
8291 -- private extension.
8293 elsif not Constraint_Present
8294 and then not Private_Extension
8295 and then not Is_Constrained (Parent_Type)
8298 ("unconstrained type not allowed in this context", Indic);
8300 elsif Constraint_Present then
8301 -- The following call sets the field Corresponding_Discriminant
8302 -- for the discriminants in the Derived_Type.
8304 Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True);
8306 -- For untagged types all new discriminants must rename
8307 -- discriminants in the parent. For private extensions new
8308 -- discriminants cannot rename old ones (implied by [7.3(13)]).
8310 Discrim := First_Discriminant (Derived_Type);
8311 while Present (Discrim) loop
8313 and then No (Corresponding_Discriminant (Discrim))
8316 ("new discriminants must constrain old ones", Discrim);
8318 elsif Private_Extension
8319 and then Present (Corresponding_Discriminant (Discrim))
8322 ("only static constraints allowed for parent"
8323 & " discriminants in the partial view", Indic);
8327 -- If a new discriminant is used in the constraint, then its
8328 -- subtype must be statically compatible with the parent
8329 -- discriminant's subtype (3.7(15)).
8331 -- However, if the record contains an array constrained by
8332 -- the discriminant but with some different bound, the compiler
8333 -- attemps to create a smaller range for the discriminant type.
8334 -- (See exp_ch3.Adjust_Discriminants). In this case, where
8335 -- the discriminant type is a scalar type, the check must use
8336 -- the original discriminant type in the parent declaration.
8339 Corr_Disc : constant Entity_Id :=
8340 Corresponding_Discriminant (Discrim);
8341 Disc_Type : constant Entity_Id := Etype (Discrim);
8342 Corr_Type : Entity_Id;
8345 if Present (Corr_Disc) then
8346 if Is_Scalar_Type (Disc_Type) then
8348 Entity (Discriminant_Type (Parent (Corr_Disc)));
8350 Corr_Type := Etype (Corr_Disc);
8354 Subtypes_Statically_Compatible (Disc_Type, Corr_Type)
8357 ("subtype must be compatible "
8358 & "with parent discriminant",
8364 Next_Discriminant (Discrim);
8367 -- Check whether the constraints of the full view statically
8368 -- match those imposed by the parent subtype [7.3(13)].
8370 if Present (Stored_Constraint (Derived_Type)) then
8375 C1 := First_Elmt (Discs);
8376 C2 := First_Elmt (Stored_Constraint (Derived_Type));
8377 while Present (C1) and then Present (C2) loop
8379 Fully_Conformant_Expressions (Node (C1), Node (C2))
8382 ("not conformant with previous declaration",
8393 -- STEP 2b: No new discriminants, inherit discriminants if any
8396 if Private_Extension then
8397 Set_Has_Unknown_Discriminants
8399 Has_Unknown_Discriminants (Parent_Type)
8400 or else Unknown_Discriminants_Present (N));
8402 -- The partial view of the parent may have unknown discriminants,
8403 -- but if the full view has discriminants and the parent type is
8404 -- in scope they must be inherited.
8406 elsif Has_Unknown_Discriminants (Parent_Type)
8408 (not Has_Discriminants (Parent_Type)
8409 or else not In_Open_Scopes (Scope (Parent_Type)))
8411 Set_Has_Unknown_Discriminants (Derived_Type);
8414 if not Has_Unknown_Discriminants (Derived_Type)
8415 and then not Has_Unknown_Discriminants (Parent_Base)
8416 and then Has_Discriminants (Parent_Type)
8418 Inherit_Discrims := True;
8419 Set_Has_Discriminants
8420 (Derived_Type, True);
8421 Set_Discriminant_Constraint
8422 (Derived_Type, Discriminant_Constraint (Parent_Base));
8425 -- The following test is true for private types (remember
8426 -- transformation 5. is not applied to those) and in an error
8429 if Constraint_Present then
8430 Discs := Build_Discriminant_Constraints (Parent_Type, Indic);
8433 -- For now mark a new derived type as constrained only if it has no
8434 -- discriminants. At the end of Build_Derived_Record_Type we properly
8435 -- set this flag in the case of private extensions. See comments in
8436 -- point 9. just before body of Build_Derived_Record_Type.
8440 not (Inherit_Discrims
8441 or else Has_Unknown_Discriminants (Derived_Type)));
8444 -- STEP 3: initialize fields of derived type
8446 Set_Is_Tagged_Type (Derived_Type, Is_Tagged);
8447 Set_Stored_Constraint (Derived_Type, No_Elist);
8449 -- Ada 2005 (AI-251): Private type-declarations can implement interfaces
8450 -- but cannot be interfaces
8452 if not Private_Extension
8453 and then Ekind (Derived_Type) /= E_Private_Type
8454 and then Ekind (Derived_Type) /= E_Limited_Private_Type
8456 if Interface_Present (Type_Def) then
8457 Analyze_Interface_Declaration (Derived_Type, Type_Def);
8460 Set_Interfaces (Derived_Type, No_Elist);
8463 -- Fields inherited from the Parent_Type
8465 Set_Has_Specified_Layout
8466 (Derived_Type, Has_Specified_Layout (Parent_Type));
8467 Set_Is_Limited_Composite
8468 (Derived_Type, Is_Limited_Composite (Parent_Type));
8469 Set_Is_Private_Composite
8470 (Derived_Type, Is_Private_Composite (Parent_Type));
8472 if Is_Tagged_Type (Parent_Type) then
8473 Set_No_Tagged_Streams_Pragma
8474 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
8477 -- Fields inherited from the Parent_Base
8479 Set_Has_Controlled_Component
8480 (Derived_Type, Has_Controlled_Component (Parent_Base));
8481 Set_Has_Non_Standard_Rep
8482 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8483 Set_Has_Primitive_Operations
8484 (Derived_Type, Has_Primitive_Operations (Parent_Base));
8486 -- Fields inherited from the Parent_Base in the non-private case
8488 if Ekind (Derived_Type) = E_Record_Type then
8489 Set_Has_Complex_Representation
8490 (Derived_Type, Has_Complex_Representation (Parent_Base));
8493 -- Fields inherited from the Parent_Base for record types
8495 if Is_Record_Type (Derived_Type) then
8497 Parent_Full : Entity_Id;
8500 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
8501 -- Parent_Base can be a private type or private extension. Go
8502 -- to the full view here to get the E_Record_Type specific flags.
8504 if Present (Full_View (Parent_Base)) then
8505 Parent_Full := Full_View (Parent_Base);
8507 Parent_Full := Parent_Base;
8510 Set_OK_To_Reorder_Components
8511 (Derived_Type, OK_To_Reorder_Components (Parent_Full));
8515 -- Set fields for private derived types
8517 if Is_Private_Type (Derived_Type) then
8518 Set_Depends_On_Private (Derived_Type, True);
8519 Set_Private_Dependents (Derived_Type, New_Elmt_List);
8521 -- Inherit fields from non private record types. If this is the
8522 -- completion of a derivation from a private type, the parent itself
8523 -- is private, and the attributes come from its full view, which must
8527 if Is_Private_Type (Parent_Base)
8528 and then not Is_Record_Type (Parent_Base)
8530 Set_Component_Alignment
8531 (Derived_Type, Component_Alignment (Full_View (Parent_Base)));
8533 (Derived_Type, C_Pass_By_Copy (Full_View (Parent_Base)));
8535 Set_Component_Alignment
8536 (Derived_Type, Component_Alignment (Parent_Base));
8538 (Derived_Type, C_Pass_By_Copy (Parent_Base));
8542 -- Set fields for tagged types
8545 Set_Direct_Primitive_Operations (Derived_Type, New_Elmt_List);
8547 -- All tagged types defined in Ada.Finalization are controlled
8549 if Chars (Scope (Derived_Type)) = Name_Finalization
8550 and then Chars (Scope (Scope (Derived_Type))) = Name_Ada
8551 and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard
8553 Set_Is_Controlled (Derived_Type);
8555 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Base));
8558 -- Minor optimization: there is no need to generate the class-wide
8559 -- entity associated with an underlying record view.
8561 if not Is_Underlying_Record_View (Derived_Type) then
8562 Make_Class_Wide_Type (Derived_Type);
8565 Set_Is_Abstract_Type (Derived_Type, Abstract_Present (Type_Def));
8567 if Has_Discriminants (Derived_Type)
8568 and then Constraint_Present
8570 Set_Stored_Constraint
8571 (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs));
8574 if Ada_Version >= Ada_2005 then
8576 Ifaces_List : Elist_Id;
8579 -- Checks rules 3.9.4 (13/2 and 14/2)
8581 if Comes_From_Source (Derived_Type)
8582 and then not Is_Private_Type (Derived_Type)
8583 and then Is_Interface (Parent_Type)
8584 and then not Is_Interface (Derived_Type)
8586 if Is_Task_Interface (Parent_Type) then
8588 ("(Ada 2005) task type required (RM 3.9.4 (13.2))",
8591 elsif Is_Protected_Interface (Parent_Type) then
8593 ("(Ada 2005) protected type required (RM 3.9.4 (14.2))",
8598 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
8600 Check_Interfaces (N, Type_Def);
8602 -- Ada 2005 (AI-251): Collect the list of progenitors that are
8603 -- not already in the parents.
8607 Ifaces_List => Ifaces_List,
8608 Exclude_Parents => True);
8610 Set_Interfaces (Derived_Type, Ifaces_List);
8612 -- If the derived type is the anonymous type created for
8613 -- a declaration whose parent has a constraint, propagate
8614 -- the interface list to the source type. This must be done
8615 -- prior to the completion of the analysis of the source type
8616 -- because the components in the extension may contain current
8617 -- instances whose legality depends on some ancestor.
8619 if Is_Itype (Derived_Type) then
8621 Def : constant Node_Id :=
8622 Associated_Node_For_Itype (Derived_Type);
8625 and then Nkind (Def) = N_Full_Type_Declaration
8628 (Defining_Identifier (Def), Ifaces_List);
8633 -- A type extension is automatically Ghost when one of its
8634 -- progenitors is Ghost (SPARK RM 6.9(9)). This property is
8635 -- also inherited when the parent type is Ghost, but this is
8636 -- done in Build_Derived_Type as the mechanism also handles
8637 -- untagged derivations.
8639 if Implements_Ghost_Interface (Derived_Type) then
8640 Set_Is_Ghost_Entity (Derived_Type);
8646 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Base));
8647 Set_Has_Non_Standard_Rep
8648 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8651 -- STEP 4: Inherit components from the parent base and constrain them.
8652 -- Apply the second transformation described in point 6. above.
8654 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
8655 or else not Has_Discriminants (Parent_Type)
8656 or else not Is_Constrained (Parent_Type)
8660 Constrs := Discriminant_Constraint (Parent_Type);
8665 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
8667 -- STEP 5a: Copy the parent record declaration for untagged types
8669 if not Is_Tagged then
8671 -- Discriminant_Constraint (Derived_Type) has been properly
8672 -- constructed. Save it and temporarily set it to Empty because we
8673 -- do not want the call to New_Copy_Tree below to mess this list.
8675 if Has_Discriminants (Derived_Type) then
8676 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
8677 Set_Discriminant_Constraint (Derived_Type, No_Elist);
8679 Save_Discr_Constr := No_Elist;
8682 -- Save the Etype field of Derived_Type. It is correctly set now,
8683 -- but the call to New_Copy tree may remap it to point to itself,
8684 -- which is not what we want. Ditto for the Next_Entity field.
8686 Save_Etype := Etype (Derived_Type);
8687 Save_Next_Entity := Next_Entity (Derived_Type);
8689 -- Assoc_List maps all stored discriminants in the Parent_Base to
8690 -- stored discriminants in the Derived_Type. It is fundamental that
8691 -- no types or itypes with discriminants other than the stored
8692 -- discriminants appear in the entities declared inside
8693 -- Derived_Type, since the back end cannot deal with it.
8697 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
8699 -- Restore the fields saved prior to the New_Copy_Tree call
8700 -- and compute the stored constraint.
8702 Set_Etype (Derived_Type, Save_Etype);
8703 Set_Next_Entity (Derived_Type, Save_Next_Entity);
8705 if Has_Discriminants (Derived_Type) then
8706 Set_Discriminant_Constraint
8707 (Derived_Type, Save_Discr_Constr);
8708 Set_Stored_Constraint
8709 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
8710 Replace_Components (Derived_Type, New_Decl);
8711 Set_Has_Implicit_Dereference
8712 (Derived_Type, Has_Implicit_Dereference (Parent_Type));
8715 -- Insert the new derived type declaration
8717 Rewrite (N, New_Decl);
8719 -- STEP 5b: Complete the processing for record extensions in generics
8721 -- There is no completion for record extensions declared in the
8722 -- parameter part of a generic, so we need to complete processing for
8723 -- these generic record extensions here. The Record_Type_Definition call
8724 -- will change the Ekind of the components from E_Void to E_Component.
8726 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
8727 Record_Type_Definition (Empty, Derived_Type);
8729 -- STEP 5c: Process the record extension for non private tagged types
8731 elsif not Private_Extension then
8732 Expand_Record_Extension (Derived_Type, Type_Def);
8734 -- Note : previously in ASIS mode we set the Parent_Subtype of the
8735 -- derived type to propagate some semantic information. This led
8736 -- to other ASIS failures and has been removed.
8738 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
8739 -- implemented interfaces if we are in expansion mode
8742 and then Has_Interfaces (Derived_Type)
8744 Add_Interface_Tag_Components (N, Derived_Type);
8747 -- Analyze the record extension
8749 Record_Type_Definition
8750 (Record_Extension_Part (Type_Def), Derived_Type);
8755 -- Nothing else to do if there is an error in the derivation.
8756 -- An unusual case: the full view may be derived from a type in an
8757 -- instance, when the partial view was used illegally as an actual
8758 -- in that instance, leading to a circular definition.
8760 if Etype (Derived_Type) = Any_Type
8761 or else Etype (Parent_Type) = Derived_Type
8766 -- Set delayed freeze and then derive subprograms, we need to do
8767 -- this in this order so that derived subprograms inherit the
8768 -- derived freeze if necessary.
8770 Set_Has_Delayed_Freeze (Derived_Type);
8772 if Derive_Subps then
8773 Derive_Subprograms (Parent_Type, Derived_Type);
8776 -- If we have a private extension which defines a constrained derived
8777 -- type mark as constrained here after we have derived subprograms. See
8778 -- comment on point 9. just above the body of Build_Derived_Record_Type.
8780 if Private_Extension and then Inherit_Discrims then
8781 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
8782 Set_Is_Constrained (Derived_Type, True);
8783 Set_Discriminant_Constraint (Derived_Type, Discs);
8785 elsif Is_Constrained (Parent_Type) then
8787 (Derived_Type, True);
8788 Set_Discriminant_Constraint
8789 (Derived_Type, Discriminant_Constraint (Parent_Type));
8793 -- Update the class-wide type, which shares the now-completed entity
8794 -- list with its specific type. In case of underlying record views,
8795 -- we do not generate the corresponding class wide entity.
8798 and then not Is_Underlying_Record_View (Derived_Type)
8801 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
8803 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
8806 Check_Function_Writable_Actuals (N);
8807 end Build_Derived_Record_Type;
8809 ------------------------
8810 -- Build_Derived_Type --
8811 ------------------------
8813 procedure Build_Derived_Type
8815 Parent_Type : Entity_Id;
8816 Derived_Type : Entity_Id;
8817 Is_Completion : Boolean;
8818 Derive_Subps : Boolean := True)
8820 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
8823 -- Set common attributes
8825 Set_Scope (Derived_Type, Current_Scope);
8827 Set_Etype (Derived_Type, Parent_Base);
8828 Set_Ekind (Derived_Type, Ekind (Parent_Base));
8829 Set_Has_Task (Derived_Type, Has_Task (Parent_Base));
8830 Set_Has_Protected (Derived_Type, Has_Protected (Parent_Base));
8832 Set_Size_Info (Derived_Type, Parent_Type);
8833 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
8834 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
8835 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
8836 Set_Is_Volatile (Derived_Type, Is_Volatile (Parent_Type));
8838 if Is_Tagged_Type (Derived_Type) then
8839 Set_No_Tagged_Streams_Pragma
8840 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
8843 -- If the parent has primitive routines, set the derived type link
8845 if Has_Primitive_Operations (Parent_Type) then
8846 Set_Derived_Type_Link (Parent_Base, Derived_Type);
8849 -- If the parent type is a private subtype, the convention on the base
8850 -- type may be set in the private part, and not propagated to the
8851 -- subtype until later, so we obtain the convention from the base type.
8853 Set_Convention (Derived_Type, Convention (Parent_Base));
8855 -- Set SSO default for record or array type
8857 if (Is_Array_Type (Derived_Type) or else Is_Record_Type (Derived_Type))
8858 and then Is_Base_Type (Derived_Type)
8860 Set_Default_SSO (Derived_Type);
8863 -- Propagate invariant information. The new type has invariants if
8864 -- they are inherited from the parent type, and these invariants can
8865 -- be further inherited, so both flags are set.
8867 -- We similarly inherit predicates
8869 if Has_Predicates (Parent_Type) then
8870 Set_Has_Predicates (Derived_Type);
8873 -- The derived type inherits the representation clauses of the parent
8875 Inherit_Rep_Item_Chain (Derived_Type, Parent_Type);
8877 -- Propagate the attributes related to pragma Default_Initial_Condition
8878 -- from the parent type to the private extension. A derived type always
8879 -- inherits the default initial condition flag from the parent type. If
8880 -- the derived type carries its own Default_Initial_Condition pragma,
8881 -- the flag is later reset in Analyze_Pragma. Note that both flags are
8882 -- mutually exclusive.
8884 Propagate_Default_Init_Cond_Attributes
8885 (From_Typ => Parent_Type,
8886 To_Typ => Derived_Type,
8887 Parent_To_Derivation => True);
8889 -- If the parent type has delayed rep aspects, then mark the derived
8890 -- type as possibly inheriting a delayed rep aspect.
8892 if Has_Delayed_Rep_Aspects (Parent_Type) then
8893 Set_May_Inherit_Delayed_Rep_Aspects (Derived_Type);
8896 -- Propagate the attributes related to pragma Ghost from the parent type
8897 -- to the derived type or type extension (SPARK RM 6.9(9)).
8899 if Is_Ghost_Entity (Parent_Type) then
8900 Set_Is_Ghost_Entity (Derived_Type);
8903 -- Type dependent processing
8905 case Ekind (Parent_Type) is
8906 when Numeric_Kind =>
8907 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
8910 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
8914 | Class_Wide_Kind =>
8915 Build_Derived_Record_Type
8916 (N, Parent_Type, Derived_Type, Derive_Subps);
8919 when Enumeration_Kind =>
8920 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
8923 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
8925 when Incomplete_Or_Private_Kind =>
8926 Build_Derived_Private_Type
8927 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
8929 -- For discriminated types, the derivation includes deriving
8930 -- primitive operations. For others it is done below.
8932 if Is_Tagged_Type (Parent_Type)
8933 or else Has_Discriminants (Parent_Type)
8934 or else (Present (Full_View (Parent_Type))
8935 and then Has_Discriminants (Full_View (Parent_Type)))
8940 when Concurrent_Kind =>
8941 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
8944 raise Program_Error;
8947 -- Nothing more to do if some error occurred
8949 if Etype (Derived_Type) = Any_Type then
8953 -- Set delayed freeze and then derive subprograms, we need to do this
8954 -- in this order so that derived subprograms inherit the derived freeze
8957 Set_Has_Delayed_Freeze (Derived_Type);
8959 if Derive_Subps then
8960 Derive_Subprograms (Parent_Type, Derived_Type);
8963 Set_Has_Primitive_Operations
8964 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
8965 end Build_Derived_Type;
8967 -----------------------
8968 -- Build_Discriminal --
8969 -----------------------
8971 procedure Build_Discriminal (Discrim : Entity_Id) is
8972 D_Minal : Entity_Id;
8973 CR_Disc : Entity_Id;
8976 -- A discriminal has the same name as the discriminant
8978 D_Minal := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
8980 Set_Ekind (D_Minal, E_In_Parameter);
8981 Set_Mechanism (D_Minal, Default_Mechanism);
8982 Set_Etype (D_Minal, Etype (Discrim));
8983 Set_Scope (D_Minal, Current_Scope);
8985 Set_Discriminal (Discrim, D_Minal);
8986 Set_Discriminal_Link (D_Minal, Discrim);
8988 -- For task types, build at once the discriminants of the corresponding
8989 -- record, which are needed if discriminants are used in entry defaults
8990 -- and in family bounds.
8992 if Is_Concurrent_Type (Current_Scope)
8994 Is_Limited_Type (Current_Scope)
8996 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
8998 Set_Ekind (CR_Disc, E_In_Parameter);
8999 Set_Mechanism (CR_Disc, Default_Mechanism);
9000 Set_Etype (CR_Disc, Etype (Discrim));
9001 Set_Scope (CR_Disc, Current_Scope);
9002 Set_Discriminal_Link (CR_Disc, Discrim);
9003 Set_CR_Discriminant (Discrim, CR_Disc);
9005 end Build_Discriminal;
9007 ------------------------------------
9008 -- Build_Discriminant_Constraints --
9009 ------------------------------------
9011 function Build_Discriminant_Constraints
9014 Derived_Def : Boolean := False) return Elist_Id
9016 C : constant Node_Id := Constraint (Def);
9017 Nb_Discr : constant Nat := Number_Discriminants (T);
9019 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
9020 -- Saves the expression corresponding to a given discriminant in T
9022 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
9023 -- Return the Position number within array Discr_Expr of a discriminant
9024 -- D within the discriminant list of the discriminated type T.
9026 procedure Process_Discriminant_Expression
9029 -- If this is a discriminant constraint on a partial view, do not
9030 -- generate an overflow check on the discriminant expression. The check
9031 -- will be generated when constraining the full view. Otherwise the
9032 -- backend creates duplicate symbols for the temporaries corresponding
9033 -- to the expressions to be checked, causing spurious assembler errors.
9039 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
9043 Disc := First_Discriminant (T);
9044 for J in Discr_Expr'Range loop
9049 Next_Discriminant (Disc);
9052 -- Note: Since this function is called on discriminants that are
9053 -- known to belong to the discriminated type, falling through the
9054 -- loop with no match signals an internal compiler error.
9056 raise Program_Error;
9059 -------------------------------------
9060 -- Process_Discriminant_Expression --
9061 -------------------------------------
9063 procedure Process_Discriminant_Expression
9067 BDT : constant Entity_Id := Base_Type (Etype (D));
9070 -- If this is a discriminant constraint on a partial view, do
9071 -- not generate an overflow on the discriminant expression. The
9072 -- check will be generated when constraining the full view.
9074 if Is_Private_Type (T)
9075 and then Present (Full_View (T))
9077 Analyze_And_Resolve (Expr, BDT, Suppress => Overflow_Check);
9079 Analyze_And_Resolve (Expr, BDT);
9081 end Process_Discriminant_Expression;
9083 -- Declarations local to Build_Discriminant_Constraints
9087 Elist : constant Elist_Id := New_Elmt_List;
9095 Discrim_Present : Boolean := False;
9097 -- Start of processing for Build_Discriminant_Constraints
9100 -- The following loop will process positional associations only.
9101 -- For a positional association, the (single) discriminant is
9102 -- implicitly specified by position, in textual order (RM 3.7.2).
9104 Discr := First_Discriminant (T);
9105 Constr := First (Constraints (C));
9106 for D in Discr_Expr'Range loop
9107 exit when Nkind (Constr) = N_Discriminant_Association;
9110 Error_Msg_N ("too few discriminants given in constraint", C);
9111 return New_Elmt_List;
9113 elsif Nkind (Constr) = N_Range
9114 or else (Nkind (Constr) = N_Attribute_Reference
9115 and then Attribute_Name (Constr) = Name_Range)
9118 ("a range is not a valid discriminant constraint", Constr);
9119 Discr_Expr (D) := Error;
9122 Process_Discriminant_Expression (Constr, Discr);
9123 Discr_Expr (D) := Constr;
9126 Next_Discriminant (Discr);
9130 if No (Discr) and then Present (Constr) then
9131 Error_Msg_N ("too many discriminants given in constraint", Constr);
9132 return New_Elmt_List;
9135 -- Named associations can be given in any order, but if both positional
9136 -- and named associations are used in the same discriminant constraint,
9137 -- then positional associations must occur first, at their normal
9138 -- position. Hence once a named association is used, the rest of the
9139 -- discriminant constraint must use only named associations.
9141 while Present (Constr) loop
9143 -- Positional association forbidden after a named association
9145 if Nkind (Constr) /= N_Discriminant_Association then
9146 Error_Msg_N ("positional association follows named one", Constr);
9147 return New_Elmt_List;
9149 -- Otherwise it is a named association
9152 -- E records the type of the discriminants in the named
9153 -- association. All the discriminants specified in the same name
9154 -- association must have the same type.
9158 -- Search the list of discriminants in T to see if the simple name
9159 -- given in the constraint matches any of them.
9161 Id := First (Selector_Names (Constr));
9162 while Present (Id) loop
9165 -- If Original_Discriminant is present, we are processing a
9166 -- generic instantiation and this is an instance node. We need
9167 -- to find the name of the corresponding discriminant in the
9168 -- actual record type T and not the name of the discriminant in
9169 -- the generic formal. Example:
9172 -- type G (D : int) is private;
9174 -- subtype W is G (D => 1);
9176 -- type Rec (X : int) is record ... end record;
9177 -- package Q is new P (G => Rec);
9179 -- At the point of the instantiation, formal type G is Rec
9180 -- and therefore when reanalyzing "subtype W is G (D => 1);"
9181 -- which really looks like "subtype W is Rec (D => 1);" at
9182 -- the point of instantiation, we want to find the discriminant
9183 -- that corresponds to D in Rec, i.e. X.
9185 if Present (Original_Discriminant (Id))
9186 and then In_Instance
9188 Discr := Find_Corresponding_Discriminant (Id, T);
9192 Discr := First_Discriminant (T);
9193 while Present (Discr) loop
9194 if Chars (Discr) = Chars (Id) then
9199 Next_Discriminant (Discr);
9203 Error_Msg_N ("& does not match any discriminant", Id);
9204 return New_Elmt_List;
9206 -- If the parent type is a generic formal, preserve the
9207 -- name of the discriminant for subsequent instances.
9208 -- see comment at the beginning of this if statement.
9210 elsif Is_Generic_Type (Root_Type (T)) then
9211 Set_Original_Discriminant (Id, Discr);
9215 Position := Pos_Of_Discr (T, Discr);
9217 if Present (Discr_Expr (Position)) then
9218 Error_Msg_N ("duplicate constraint for discriminant&", Id);
9221 -- Each discriminant specified in the same named association
9222 -- must be associated with a separate copy of the
9223 -- corresponding expression.
9225 if Present (Next (Id)) then
9226 Expr := New_Copy_Tree (Expression (Constr));
9227 Set_Parent (Expr, Parent (Expression (Constr)));
9229 Expr := Expression (Constr);
9232 Discr_Expr (Position) := Expr;
9233 Process_Discriminant_Expression (Expr, Discr);
9236 -- A discriminant association with more than one discriminant
9237 -- name is only allowed if the named discriminants are all of
9238 -- the same type (RM 3.7.1(8)).
9241 E := Base_Type (Etype (Discr));
9243 elsif Base_Type (Etype (Discr)) /= E then
9245 ("all discriminants in an association " &
9246 "must have the same type", Id);
9256 -- A discriminant constraint must provide exactly one value for each
9257 -- discriminant of the type (RM 3.7.1(8)).
9259 for J in Discr_Expr'Range loop
9260 if No (Discr_Expr (J)) then
9261 Error_Msg_N ("too few discriminants given in constraint", C);
9262 return New_Elmt_List;
9266 -- Determine if there are discriminant expressions in the constraint
9268 for J in Discr_Expr'Range loop
9269 if Denotes_Discriminant
9270 (Discr_Expr (J), Check_Concurrent => True)
9272 Discrim_Present := True;
9276 -- Build an element list consisting of the expressions given in the
9277 -- discriminant constraint and apply the appropriate checks. The list
9278 -- is constructed after resolving any named discriminant associations
9279 -- and therefore the expressions appear in the textual order of the
9282 Discr := First_Discriminant (T);
9283 for J in Discr_Expr'Range loop
9284 if Discr_Expr (J) /= Error then
9285 Append_Elmt (Discr_Expr (J), Elist);
9287 -- If any of the discriminant constraints is given by a
9288 -- discriminant and we are in a derived type declaration we
9289 -- have a discriminant renaming. Establish link between new
9290 -- and old discriminant.
9292 if Denotes_Discriminant (Discr_Expr (J)) then
9294 Set_Corresponding_Discriminant
9295 (Entity (Discr_Expr (J)), Discr);
9298 -- Force the evaluation of non-discriminant expressions.
9299 -- If we have found a discriminant in the constraint 3.4(26)
9300 -- and 3.8(18) demand that no range checks are performed are
9301 -- after evaluation. If the constraint is for a component
9302 -- definition that has a per-object constraint, expressions are
9303 -- evaluated but not checked either. In all other cases perform
9307 if Discrim_Present then
9310 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
9312 Has_Per_Object_Constraint
9313 (Defining_Identifier (Parent (Parent (Def))))
9317 elsif Is_Access_Type (Etype (Discr)) then
9318 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
9321 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
9324 Force_Evaluation (Discr_Expr (J));
9327 -- Check that the designated type of an access discriminant's
9328 -- expression is not a class-wide type unless the discriminant's
9329 -- designated type is also class-wide.
9331 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
9332 and then not Is_Class_Wide_Type
9333 (Designated_Type (Etype (Discr)))
9334 and then Etype (Discr_Expr (J)) /= Any_Type
9335 and then Is_Class_Wide_Type
9336 (Designated_Type (Etype (Discr_Expr (J))))
9338 Wrong_Type (Discr_Expr (J), Etype (Discr));
9340 elsif Is_Access_Type (Etype (Discr))
9341 and then not Is_Access_Constant (Etype (Discr))
9342 and then Is_Access_Type (Etype (Discr_Expr (J)))
9343 and then Is_Access_Constant (Etype (Discr_Expr (J)))
9346 ("constraint for discriminant& must be access to variable",
9351 Next_Discriminant (Discr);
9355 end Build_Discriminant_Constraints;
9357 ---------------------------------
9358 -- Build_Discriminated_Subtype --
9359 ---------------------------------
9361 procedure Build_Discriminated_Subtype
9365 Related_Nod : Node_Id;
9366 For_Access : Boolean := False)
9368 Has_Discrs : constant Boolean := Has_Discriminants (T);
9369 Constrained : constant Boolean :=
9371 and then not Is_Empty_Elmt_List (Elist)
9372 and then not Is_Class_Wide_Type (T))
9373 or else Is_Constrained (T);
9376 if Ekind (T) = E_Record_Type then
9378 Set_Ekind (Def_Id, E_Private_Subtype);
9379 Set_Is_For_Access_Subtype (Def_Id, True);
9381 Set_Ekind (Def_Id, E_Record_Subtype);
9384 -- Inherit preelaboration flag from base, for types for which it
9385 -- may have been set: records, private types, protected types.
9387 Set_Known_To_Have_Preelab_Init
9388 (Def_Id, Known_To_Have_Preelab_Init (T));
9390 elsif Ekind (T) = E_Task_Type then
9391 Set_Ekind (Def_Id, E_Task_Subtype);
9393 elsif Ekind (T) = E_Protected_Type then
9394 Set_Ekind (Def_Id, E_Protected_Subtype);
9395 Set_Known_To_Have_Preelab_Init
9396 (Def_Id, Known_To_Have_Preelab_Init (T));
9398 elsif Is_Private_Type (T) then
9399 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
9400 Set_Known_To_Have_Preelab_Init
9401 (Def_Id, Known_To_Have_Preelab_Init (T));
9403 -- Private subtypes may have private dependents
9405 Set_Private_Dependents (Def_Id, New_Elmt_List);
9407 elsif Is_Class_Wide_Type (T) then
9408 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
9411 -- Incomplete type. Attach subtype to list of dependents, to be
9412 -- completed with full view of parent type, unless is it the
9413 -- designated subtype of a record component within an init_proc.
9414 -- This last case arises for a component of an access type whose
9415 -- designated type is incomplete (e.g. a Taft Amendment type).
9416 -- The designated subtype is within an inner scope, and needs no
9417 -- elaboration, because only the access type is needed in the
9418 -- initialization procedure.
9420 Set_Ekind (Def_Id, Ekind (T));
9422 if For_Access and then Within_Init_Proc then
9425 Append_Elmt (Def_Id, Private_Dependents (T));
9429 Set_Etype (Def_Id, T);
9430 Init_Size_Align (Def_Id);
9431 Set_Has_Discriminants (Def_Id, Has_Discrs);
9432 Set_Is_Constrained (Def_Id, Constrained);
9434 Set_First_Entity (Def_Id, First_Entity (T));
9435 Set_Last_Entity (Def_Id, Last_Entity (T));
9436 Set_Has_Implicit_Dereference
9437 (Def_Id, Has_Implicit_Dereference (T));
9439 -- If the subtype is the completion of a private declaration, there may
9440 -- have been representation clauses for the partial view, and they must
9441 -- be preserved. Build_Derived_Type chains the inherited clauses with
9442 -- the ones appearing on the extension. If this comes from a subtype
9443 -- declaration, all clauses are inherited.
9445 if No (First_Rep_Item (Def_Id)) then
9446 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
9449 if Is_Tagged_Type (T) then
9450 Set_Is_Tagged_Type (Def_Id);
9451 Set_No_Tagged_Streams_Pragma (Def_Id, No_Tagged_Streams_Pragma (T));
9452 Make_Class_Wide_Type (Def_Id);
9455 Set_Stored_Constraint (Def_Id, No_Elist);
9458 Set_Discriminant_Constraint (Def_Id, Elist);
9459 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
9462 if Is_Tagged_Type (T) then
9464 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
9465 -- concurrent record type (which has the list of primitive
9468 if Ada_Version >= Ada_2005
9469 and then Is_Concurrent_Type (T)
9471 Set_Corresponding_Record_Type (Def_Id,
9472 Corresponding_Record_Type (T));
9474 Set_Direct_Primitive_Operations (Def_Id,
9475 Direct_Primitive_Operations (T));
9478 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
9481 -- Subtypes introduced by component declarations do not need to be
9482 -- marked as delayed, and do not get freeze nodes, because the semantics
9483 -- verifies that the parents of the subtypes are frozen before the
9484 -- enclosing record is frozen.
9486 if not Is_Type (Scope (Def_Id)) then
9487 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
9489 if Is_Private_Type (T)
9490 and then Present (Full_View (T))
9492 Conditional_Delay (Def_Id, Full_View (T));
9494 Conditional_Delay (Def_Id, T);
9498 if Is_Record_Type (T) then
9499 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
9502 and then not Is_Empty_Elmt_List (Elist)
9503 and then not For_Access
9505 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
9506 elsif not For_Access then
9507 Set_Cloned_Subtype (Def_Id, T);
9510 end Build_Discriminated_Subtype;
9512 ---------------------------
9513 -- Build_Itype_Reference --
9514 ---------------------------
9516 procedure Build_Itype_Reference
9520 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
9523 -- Itype references are only created for use by the back-end
9525 if Inside_A_Generic then
9528 Set_Itype (IR, Ityp);
9529 Insert_After (Nod, IR);
9531 end Build_Itype_Reference;
9533 ------------------------
9534 -- Build_Scalar_Bound --
9535 ------------------------
9537 function Build_Scalar_Bound
9540 Der_T : Entity_Id) return Node_Id
9542 New_Bound : Entity_Id;
9545 -- Note: not clear why this is needed, how can the original bound
9546 -- be unanalyzed at this point? and if it is, what business do we
9547 -- have messing around with it? and why is the base type of the
9548 -- parent type the right type for the resolution. It probably is
9549 -- not. It is OK for the new bound we are creating, but not for
9550 -- the old one??? Still if it never happens, no problem.
9552 Analyze_And_Resolve (Bound, Base_Type (Par_T));
9554 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
9555 New_Bound := New_Copy (Bound);
9556 Set_Etype (New_Bound, Der_T);
9557 Set_Analyzed (New_Bound);
9559 elsif Is_Entity_Name (Bound) then
9560 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
9562 -- The following is almost certainly wrong. What business do we have
9563 -- relocating a node (Bound) that is presumably still attached to
9564 -- the tree elsewhere???
9567 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
9570 Set_Etype (New_Bound, Der_T);
9572 end Build_Scalar_Bound;
9574 --------------------------------
9575 -- Build_Underlying_Full_View --
9576 --------------------------------
9578 procedure Build_Underlying_Full_View
9583 Loc : constant Source_Ptr := Sloc (N);
9584 Subt : constant Entity_Id :=
9585 Make_Defining_Identifier
9586 (Loc, New_External_Name (Chars (Typ), 'S'));
9593 procedure Set_Discriminant_Name (Id : Node_Id);
9594 -- If the derived type has discriminants, they may rename discriminants
9595 -- of the parent. When building the full view of the parent, we need to
9596 -- recover the names of the original discriminants if the constraint is
9597 -- given by named associations.
9599 ---------------------------
9600 -- Set_Discriminant_Name --
9601 ---------------------------
9603 procedure Set_Discriminant_Name (Id : Node_Id) is
9607 Set_Original_Discriminant (Id, Empty);
9609 if Has_Discriminants (Typ) then
9610 Disc := First_Discriminant (Typ);
9611 while Present (Disc) loop
9612 if Chars (Disc) = Chars (Id)
9613 and then Present (Corresponding_Discriminant (Disc))
9615 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
9617 Next_Discriminant (Disc);
9620 end Set_Discriminant_Name;
9622 -- Start of processing for Build_Underlying_Full_View
9625 if Nkind (N) = N_Full_Type_Declaration then
9626 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
9628 elsif Nkind (N) = N_Subtype_Declaration then
9629 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
9631 elsif Nkind (N) = N_Component_Declaration then
9634 (Constraint (Subtype_Indication (Component_Definition (N))));
9637 raise Program_Error;
9640 C := First (Constraints (Constr));
9641 while Present (C) loop
9642 if Nkind (C) = N_Discriminant_Association then
9643 Id := First (Selector_Names (C));
9644 while Present (Id) loop
9645 Set_Discriminant_Name (Id);
9654 Make_Subtype_Declaration (Loc,
9655 Defining_Identifier => Subt,
9656 Subtype_Indication =>
9657 Make_Subtype_Indication (Loc,
9658 Subtype_Mark => New_Occurrence_Of (Par, Loc),
9659 Constraint => New_Copy_Tree (Constr)));
9661 -- If this is a component subtype for an outer itype, it is not
9662 -- a list member, so simply set the parent link for analysis: if
9663 -- the enclosing type does not need to be in a declarative list,
9664 -- neither do the components.
9666 if Is_List_Member (N)
9667 and then Nkind (N) /= N_Component_Declaration
9669 Insert_Before (N, Indic);
9671 Set_Parent (Indic, Parent (N));
9675 Set_Underlying_Full_View (Typ, Full_View (Subt));
9676 end Build_Underlying_Full_View;
9678 -------------------------------
9679 -- Check_Abstract_Overriding --
9680 -------------------------------
9682 procedure Check_Abstract_Overriding (T : Entity_Id) is
9683 Alias_Subp : Entity_Id;
9689 procedure Check_Pragma_Implemented (Subp : Entity_Id);
9690 -- Ada 2012 (AI05-0030): Subprogram Subp overrides an interface routine
9691 -- which has pragma Implemented already set. Check whether Subp's entity
9692 -- kind conforms to the implementation kind of the overridden routine.
9694 procedure Check_Pragma_Implemented
9696 Iface_Subp : Entity_Id);
9697 -- Ada 2012 (AI05-0030): Subprogram Subp overrides interface routine
9698 -- Iface_Subp and both entities have pragma Implemented already set on
9699 -- them. Check whether the two implementation kinds are conforming.
9701 procedure Inherit_Pragma_Implemented
9703 Iface_Subp : Entity_Id);
9704 -- Ada 2012 (AI05-0030): Interface primitive Subp overrides interface
9705 -- subprogram Iface_Subp which has been marked by pragma Implemented.
9706 -- Propagate the implementation kind of Iface_Subp to Subp.
9708 ------------------------------
9709 -- Check_Pragma_Implemented --
9710 ------------------------------
9712 procedure Check_Pragma_Implemented (Subp : Entity_Id) is
9713 Iface_Alias : constant Entity_Id := Interface_Alias (Subp);
9714 Impl_Kind : constant Name_Id := Implementation_Kind (Iface_Alias);
9715 Subp_Alias : constant Entity_Id := Alias (Subp);
9716 Contr_Typ : Entity_Id;
9717 Impl_Subp : Entity_Id;
9720 -- Subp must have an alias since it is a hidden entity used to link
9721 -- an interface subprogram to its overriding counterpart.
9723 pragma Assert (Present (Subp_Alias));
9725 -- Handle aliases to synchronized wrappers
9727 Impl_Subp := Subp_Alias;
9729 if Is_Primitive_Wrapper (Impl_Subp) then
9730 Impl_Subp := Wrapped_Entity (Impl_Subp);
9733 -- Extract the type of the controlling formal
9735 Contr_Typ := Etype (First_Formal (Subp_Alias));
9737 if Is_Concurrent_Record_Type (Contr_Typ) then
9738 Contr_Typ := Corresponding_Concurrent_Type (Contr_Typ);
9741 -- An interface subprogram whose implementation kind is By_Entry must
9742 -- be implemented by an entry.
9744 if Impl_Kind = Name_By_Entry
9745 and then Ekind (Impl_Subp) /= E_Entry
9747 Error_Msg_Node_2 := Iface_Alias;
9749 ("type & must implement abstract subprogram & with an entry",
9750 Subp_Alias, Contr_Typ);
9752 elsif Impl_Kind = Name_By_Protected_Procedure then
9754 -- An interface subprogram whose implementation kind is By_
9755 -- Protected_Procedure cannot be implemented by a primitive
9756 -- procedure of a task type.
9758 if Ekind (Contr_Typ) /= E_Protected_Type then
9759 Error_Msg_Node_2 := Contr_Typ;
9761 ("interface subprogram & cannot be implemented by a " &
9762 "primitive procedure of task type &", Subp_Alias,
9765 -- An interface subprogram whose implementation kind is By_
9766 -- Protected_Procedure must be implemented by a procedure.
9768 elsif Ekind (Impl_Subp) /= E_Procedure then
9769 Error_Msg_Node_2 := Iface_Alias;
9771 ("type & must implement abstract subprogram & with a " &
9772 "procedure", Subp_Alias, Contr_Typ);
9774 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
9775 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
9777 Error_Msg_Name_1 := Impl_Kind;
9779 ("overriding operation& must have synchronization%",
9783 -- If primitive has Optional synchronization, overriding operation
9784 -- must match if it has an explicit synchronization..
9786 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
9787 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
9789 Error_Msg_Name_1 := Impl_Kind;
9791 ("overriding operation& must have syncrhonization%",
9794 end Check_Pragma_Implemented;
9796 ------------------------------
9797 -- Check_Pragma_Implemented --
9798 ------------------------------
9800 procedure Check_Pragma_Implemented
9802 Iface_Subp : Entity_Id)
9804 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
9805 Subp_Kind : constant Name_Id := Implementation_Kind (Subp);
9808 -- Ada 2012 (AI05-0030): The implementation kinds of an overridden
9809 -- and overriding subprogram are different. In general this is an
9810 -- error except when the implementation kind of the overridden
9811 -- subprograms is By_Any or Optional.
9813 if Iface_Kind /= Subp_Kind
9814 and then Iface_Kind /= Name_By_Any
9815 and then Iface_Kind /= Name_Optional
9817 if Iface_Kind = Name_By_Entry then
9819 ("incompatible implementation kind, overridden subprogram " &
9820 "is marked By_Entry", Subp);
9823 ("incompatible implementation kind, overridden subprogram " &
9824 "is marked By_Protected_Procedure", Subp);
9827 end Check_Pragma_Implemented;
9829 --------------------------------
9830 -- Inherit_Pragma_Implemented --
9831 --------------------------------
9833 procedure Inherit_Pragma_Implemented
9835 Iface_Subp : Entity_Id)
9837 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
9838 Loc : constant Source_Ptr := Sloc (Subp);
9839 Impl_Prag : Node_Id;
9842 -- Since the implementation kind is stored as a representation item
9843 -- rather than a flag, create a pragma node.
9847 Chars => Name_Implemented,
9848 Pragma_Argument_Associations => New_List (
9849 Make_Pragma_Argument_Association (Loc,
9850 Expression => New_Occurrence_Of (Subp, Loc)),
9852 Make_Pragma_Argument_Association (Loc,
9853 Expression => Make_Identifier (Loc, Iface_Kind))));
9855 -- The pragma doesn't need to be analyzed because it is internally
9856 -- built. It is safe to directly register it as a rep item since we
9857 -- are only interested in the characters of the implementation kind.
9859 Record_Rep_Item (Subp, Impl_Prag);
9860 end Inherit_Pragma_Implemented;
9862 -- Start of processing for Check_Abstract_Overriding
9865 Op_List := Primitive_Operations (T);
9867 -- Loop to check primitive operations
9869 Elmt := First_Elmt (Op_List);
9870 while Present (Elmt) loop
9871 Subp := Node (Elmt);
9872 Alias_Subp := Alias (Subp);
9874 -- Inherited subprograms are identified by the fact that they do not
9875 -- come from source, and the associated source location is the
9876 -- location of the first subtype of the derived type.
9878 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
9879 -- subprograms that "require overriding".
9881 -- Special exception, do not complain about failure to override the
9882 -- stream routines _Input and _Output, as well as the primitive
9883 -- operations used in dispatching selects since we always provide
9884 -- automatic overridings for these subprograms.
9886 -- Also ignore this rule for convention CIL since .NET libraries
9887 -- do bizarre things with interfaces???
9889 -- The partial view of T may have been a private extension, for
9890 -- which inherited functions dispatching on result are abstract.
9891 -- If the full view is a null extension, there is no need for
9892 -- overriding in Ada 2005, but wrappers need to be built for them
9893 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
9895 if Is_Null_Extension (T)
9896 and then Has_Controlling_Result (Subp)
9897 and then Ada_Version >= Ada_2005
9898 and then Present (Alias_Subp)
9899 and then not Comes_From_Source (Subp)
9900 and then not Is_Abstract_Subprogram (Alias_Subp)
9901 and then not Is_Access_Type (Etype (Subp))
9905 -- Ada 2005 (AI-251): Internal entities of interfaces need no
9906 -- processing because this check is done with the aliased
9909 elsif Present (Interface_Alias (Subp)) then
9912 elsif (Is_Abstract_Subprogram (Subp)
9913 or else Requires_Overriding (Subp)
9915 (Has_Controlling_Result (Subp)
9916 and then Present (Alias_Subp)
9917 and then not Comes_From_Source (Subp)
9918 and then Sloc (Subp) = Sloc (First_Subtype (T))))
9919 and then not Is_TSS (Subp, TSS_Stream_Input)
9920 and then not Is_TSS (Subp, TSS_Stream_Output)
9921 and then not Is_Abstract_Type (T)
9922 and then Convention (T) /= Convention_CIL
9923 and then not Is_Predefined_Interface_Primitive (Subp)
9925 -- Ada 2005 (AI-251): Do not consider hidden entities associated
9926 -- with abstract interface types because the check will be done
9927 -- with the aliased entity (otherwise we generate a duplicated
9930 and then not Present (Interface_Alias (Subp))
9932 if Present (Alias_Subp) then
9934 -- Only perform the check for a derived subprogram when the
9935 -- type has an explicit record extension. This avoids incorrect
9936 -- flagging of abstract subprograms for the case of a type
9937 -- without an extension that is derived from a formal type
9938 -- with a tagged actual (can occur within a private part).
9940 -- Ada 2005 (AI-391): In the case of an inherited function with
9941 -- a controlling result of the type, the rule does not apply if
9942 -- the type is a null extension (unless the parent function
9943 -- itself is abstract, in which case the function must still be
9944 -- be overridden). The expander will generate an overriding
9945 -- wrapper function calling the parent subprogram (see
9946 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
9948 Type_Def := Type_Definition (Parent (T));
9950 if Nkind (Type_Def) = N_Derived_Type_Definition
9951 and then Present (Record_Extension_Part (Type_Def))
9953 (Ada_Version < Ada_2005
9954 or else not Is_Null_Extension (T)
9955 or else Ekind (Subp) = E_Procedure
9956 or else not Has_Controlling_Result (Subp)
9957 or else Is_Abstract_Subprogram (Alias_Subp)
9958 or else Requires_Overriding (Subp)
9959 or else Is_Access_Type (Etype (Subp)))
9961 -- Avoid reporting error in case of abstract predefined
9962 -- primitive inherited from interface type because the
9963 -- body of internally generated predefined primitives
9964 -- of tagged types are generated later by Freeze_Type
9966 if Is_Interface (Root_Type (T))
9967 and then Is_Abstract_Subprogram (Subp)
9968 and then Is_Predefined_Dispatching_Operation (Subp)
9969 and then not Comes_From_Source (Ultimate_Alias (Subp))
9973 -- A null extension is not obliged to override an inherited
9974 -- procedure subject to pragma Extensions_Visible with value
9975 -- False and at least one controlling OUT parameter
9976 -- (SPARK RM 6.1.7(6)).
9978 elsif Is_Null_Extension (T)
9979 and then Is_EVF_Procedure (Subp)
9985 ("type must be declared abstract or & overridden",
9988 -- Traverse the whole chain of aliased subprograms to
9989 -- complete the error notification. This is especially
9990 -- useful for traceability of the chain of entities when
9991 -- the subprogram corresponds with an interface
9992 -- subprogram (which may be defined in another package).
9994 if Present (Alias_Subp) then
10000 while Present (Alias (E)) loop
10002 -- Avoid reporting redundant errors on entities
10003 -- inherited from interfaces
10005 if Sloc (E) /= Sloc (T) then
10006 Error_Msg_Sloc := Sloc (E);
10008 ("\& has been inherited #", T, Subp);
10014 Error_Msg_Sloc := Sloc (E);
10016 -- AI05-0068: report if there is an overriding
10017 -- non-abstract subprogram that is invisible.
10020 and then not Is_Abstract_Subprogram (E)
10023 ("\& subprogram# is not visible",
10026 -- Clarify the case where a non-null extension must
10027 -- override inherited procedure subject to pragma
10028 -- Extensions_Visible with value False and at least
10029 -- one controlling OUT param.
10031 elsif Is_EVF_Procedure (E) then
10033 ("\& # is subject to Extensions_Visible False",
10038 ("\& has been inherited from subprogram #",
10045 -- Ada 2005 (AI-345): Protected or task type implementing
10046 -- abstract interfaces.
10048 elsif Is_Concurrent_Record_Type (T)
10049 and then Present (Interfaces (T))
10051 -- If an inherited subprogram is implemented by a protected
10052 -- procedure or an entry, then the first parameter of the
10053 -- inherited subprogram shall be of mode OUT or IN OUT, or
10054 -- an access-to-variable parameter (RM 9.4(11.9/3))
10056 if Is_Protected_Type (Corresponding_Concurrent_Type (T))
10057 and then Ekind (First_Formal (Subp)) = E_In_Parameter
10058 and then Ekind (Subp) /= E_Function
10059 and then not Is_Predefined_Dispatching_Operation (Subp)
10061 Error_Msg_PT (T, Subp);
10063 -- Some other kind of overriding failure
10067 ("interface subprogram & must be overridden",
10070 -- Examine primitive operations of synchronized type,
10071 -- to find homonyms that have the wrong profile.
10078 First_Entity (Corresponding_Concurrent_Type (T));
10079 while Present (Prim) loop
10080 if Chars (Prim) = Chars (Subp) then
10082 ("profile is not type conformant with "
10083 & "prefixed view profile of "
10084 & "inherited operation&", Prim, Subp);
10087 Next_Entity (Prim);
10094 Error_Msg_Node_2 := T;
10096 ("abstract subprogram& not allowed for type&", Subp);
10098 -- Also post unconditional warning on the type (unconditional
10099 -- so that if there are more than one of these cases, we get
10100 -- them all, and not just the first one).
10102 Error_Msg_Node_2 := Subp;
10103 Error_Msg_N ("nonabstract type& has abstract subprogram&!", T);
10106 -- A subprogram subject to pragma Extensions_Visible with value
10107 -- "True" cannot override a subprogram subject to the same pragma
10108 -- with value "False" (SPARK RM 6.1.7(5)).
10110 elsif Extensions_Visible_Status (Subp) = Extensions_Visible_True
10111 and then Present (Overridden_Operation (Subp))
10112 and then Extensions_Visible_Status (Overridden_Operation (Subp)) =
10113 Extensions_Visible_False
10115 Error_Msg_Sloc := Sloc (Overridden_Operation (Subp));
10117 ("subprogram & with Extensions_Visible True cannot override "
10118 & "subprogram # with Extensions_Visible False", Subp);
10121 -- Ada 2012 (AI05-0030): Perform checks related to pragma Implemented
10123 -- Subp is an expander-generated procedure which maps an interface
10124 -- alias to a protected wrapper. The interface alias is flagged by
10125 -- pragma Implemented. Ensure that Subp is a procedure when the
10126 -- implementation kind is By_Protected_Procedure or an entry when
10129 if Ada_Version >= Ada_2012
10130 and then Is_Hidden (Subp)
10131 and then Present (Interface_Alias (Subp))
10132 and then Has_Rep_Pragma (Interface_Alias (Subp), Name_Implemented)
10134 Check_Pragma_Implemented (Subp);
10137 -- Subp is an interface primitive which overrides another interface
10138 -- primitive marked with pragma Implemented.
10140 if Ada_Version >= Ada_2012
10141 and then Present (Overridden_Operation (Subp))
10142 and then Has_Rep_Pragma
10143 (Overridden_Operation (Subp), Name_Implemented)
10145 -- If the overriding routine is also marked by Implemented, check
10146 -- that the two implementation kinds are conforming.
10148 if Has_Rep_Pragma (Subp, Name_Implemented) then
10149 Check_Pragma_Implemented
10151 Iface_Subp => Overridden_Operation (Subp));
10153 -- Otherwise the overriding routine inherits the implementation
10154 -- kind from the overridden subprogram.
10157 Inherit_Pragma_Implemented
10159 Iface_Subp => Overridden_Operation (Subp));
10163 -- If the operation is a wrapper for a synchronized primitive, it
10164 -- may be called indirectly through a dispatching select. We assume
10165 -- that it will be referenced elsewhere indirectly, and suppress
10166 -- warnings about an unused entity.
10168 if Is_Primitive_Wrapper (Subp)
10169 and then Present (Wrapped_Entity (Subp))
10171 Set_Referenced (Wrapped_Entity (Subp));
10176 end Check_Abstract_Overriding;
10178 ------------------------------------------------
10179 -- Check_Access_Discriminant_Requires_Limited --
10180 ------------------------------------------------
10182 procedure Check_Access_Discriminant_Requires_Limited
10187 -- A discriminant_specification for an access discriminant shall appear
10188 -- only in the declaration for a task or protected type, or for a type
10189 -- with the reserved word 'limited' in its definition or in one of its
10190 -- ancestors (RM 3.7(10)).
10192 -- AI-0063: The proper condition is that type must be immutably limited,
10193 -- or else be a partial view.
10195 if Nkind (Discriminant_Type (D)) = N_Access_Definition then
10196 if Is_Limited_View (Current_Scope)
10198 (Nkind (Parent (Current_Scope)) = N_Private_Type_Declaration
10199 and then Limited_Present (Parent (Current_Scope)))
10205 ("access discriminants allowed only for limited types", Loc);
10208 end Check_Access_Discriminant_Requires_Limited;
10210 -----------------------------------
10211 -- Check_Aliased_Component_Types --
10212 -----------------------------------
10214 procedure Check_Aliased_Component_Types (T : Entity_Id) is
10218 -- ??? Also need to check components of record extensions, but not
10219 -- components of protected types (which are always limited).
10221 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
10222 -- types to be unconstrained. This is safe because it is illegal to
10223 -- create access subtypes to such types with explicit discriminant
10226 if not Is_Limited_Type (T) then
10227 if Ekind (T) = E_Record_Type then
10228 C := First_Component (T);
10229 while Present (C) loop
10231 and then Has_Discriminants (Etype (C))
10232 and then not Is_Constrained (Etype (C))
10233 and then not In_Instance_Body
10234 and then Ada_Version < Ada_2005
10237 ("aliased component must be constrained (RM 3.6(11))",
10241 Next_Component (C);
10244 elsif Ekind (T) = E_Array_Type then
10245 if Has_Aliased_Components (T)
10246 and then Has_Discriminants (Component_Type (T))
10247 and then not Is_Constrained (Component_Type (T))
10248 and then not In_Instance_Body
10249 and then Ada_Version < Ada_2005
10252 ("aliased component type must be constrained (RM 3.6(11))",
10257 end Check_Aliased_Component_Types;
10259 ---------------------------------------
10260 -- Check_Anonymous_Access_Components --
10261 ---------------------------------------
10263 procedure Check_Anonymous_Access_Components
10264 (Typ_Decl : Node_Id;
10267 Comp_List : Node_Id)
10269 Loc : constant Source_Ptr := Sloc (Typ_Decl);
10270 Anon_Access : Entity_Id;
10273 Comp_Def : Node_Id;
10275 Type_Def : Node_Id;
10277 procedure Build_Incomplete_Type_Declaration;
10278 -- If the record type contains components that include an access to the
10279 -- current record, then create an incomplete type declaration for the
10280 -- record, to be used as the designated type of the anonymous access.
10281 -- This is done only once, and only if there is no previous partial
10282 -- view of the type.
10284 function Designates_T (Subt : Node_Id) return Boolean;
10285 -- Check whether a node designates the enclosing record type, or 'Class
10288 function Mentions_T (Acc_Def : Node_Id) return Boolean;
10289 -- Check whether an access definition includes a reference to
10290 -- the enclosing record type. The reference can be a subtype mark
10291 -- in the access definition itself, a 'Class attribute reference, or
10292 -- recursively a reference appearing in a parameter specification
10293 -- or result definition of an access_to_subprogram definition.
10295 --------------------------------------
10296 -- Build_Incomplete_Type_Declaration --
10297 --------------------------------------
10299 procedure Build_Incomplete_Type_Declaration is
10304 -- Is_Tagged indicates whether the type is tagged. It is tagged if
10305 -- it's "is new ... with record" or else "is tagged record ...".
10307 Is_Tagged : constant Boolean :=
10308 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
10310 Present (Record_Extension_Part (Type_Definition (Typ_Decl))))
10312 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
10313 and then Tagged_Present (Type_Definition (Typ_Decl)));
10316 -- If there is a previous partial view, no need to create a new one
10317 -- If the partial view, given by Prev, is incomplete, If Prev is
10318 -- a private declaration, full declaration is flagged accordingly.
10320 if Prev /= Typ then
10322 Make_Class_Wide_Type (Prev);
10323 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
10324 Set_Etype (Class_Wide_Type (Typ), Typ);
10329 elsif Has_Private_Declaration (Typ) then
10331 -- If we refer to T'Class inside T, and T is the completion of a
10332 -- private type, then make sure the class-wide type exists.
10335 Make_Class_Wide_Type (Typ);
10340 -- If there was a previous anonymous access type, the incomplete
10341 -- type declaration will have been created already.
10343 elsif Present (Current_Entity (Typ))
10344 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
10345 and then Full_View (Current_Entity (Typ)) = Typ
10348 and then Comes_From_Source (Current_Entity (Typ))
10349 and then not Is_Tagged_Type (Current_Entity (Typ))
10351 Make_Class_Wide_Type (Typ);
10353 ("incomplete view of tagged type should be declared tagged??",
10354 Parent (Current_Entity (Typ)));
10359 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
10360 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
10362 -- Type has already been inserted into the current scope. Remove
10363 -- it, and add incomplete declaration for type, so that subsequent
10364 -- anonymous access types can use it. The entity is unchained from
10365 -- the homonym list and from immediate visibility. After analysis,
10366 -- the entity in the incomplete declaration becomes immediately
10367 -- visible in the record declaration that follows.
10369 H := Current_Entity (Typ);
10372 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
10375 and then Homonym (H) /= Typ
10377 H := Homonym (Typ);
10380 Set_Homonym (H, Homonym (Typ));
10383 Insert_Before (Typ_Decl, Decl);
10385 Set_Full_View (Inc_T, Typ);
10389 -- Create a common class-wide type for both views, and set the
10390 -- Etype of the class-wide type to the full view.
10392 Make_Class_Wide_Type (Inc_T);
10393 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
10394 Set_Etype (Class_Wide_Type (Typ), Typ);
10397 end Build_Incomplete_Type_Declaration;
10403 function Designates_T (Subt : Node_Id) return Boolean is
10404 Type_Id : constant Name_Id := Chars (Typ);
10406 function Names_T (Nam : Node_Id) return Boolean;
10407 -- The record type has not been introduced in the current scope
10408 -- yet, so we must examine the name of the type itself, either
10409 -- an identifier T, or an expanded name of the form P.T, where
10410 -- P denotes the current scope.
10416 function Names_T (Nam : Node_Id) return Boolean is
10418 if Nkind (Nam) = N_Identifier then
10419 return Chars (Nam) = Type_Id;
10421 elsif Nkind (Nam) = N_Selected_Component then
10422 if Chars (Selector_Name (Nam)) = Type_Id then
10423 if Nkind (Prefix (Nam)) = N_Identifier then
10424 return Chars (Prefix (Nam)) = Chars (Current_Scope);
10426 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
10427 return Chars (Selector_Name (Prefix (Nam))) =
10428 Chars (Current_Scope);
10442 -- Start of processing for Designates_T
10445 if Nkind (Subt) = N_Identifier then
10446 return Chars (Subt) = Type_Id;
10448 -- Reference can be through an expanded name which has not been
10449 -- analyzed yet, and which designates enclosing scopes.
10451 elsif Nkind (Subt) = N_Selected_Component then
10452 if Names_T (Subt) then
10455 -- Otherwise it must denote an entity that is already visible.
10456 -- The access definition may name a subtype of the enclosing
10457 -- type, if there is a previous incomplete declaration for it.
10460 Find_Selected_Component (Subt);
10462 Is_Entity_Name (Subt)
10463 and then Scope (Entity (Subt)) = Current_Scope
10465 (Chars (Base_Type (Entity (Subt))) = Type_Id
10467 (Is_Class_Wide_Type (Entity (Subt))
10469 Chars (Etype (Base_Type (Entity (Subt)))) =
10473 -- A reference to the current type may appear as the prefix of
10474 -- a 'Class attribute.
10476 elsif Nkind (Subt) = N_Attribute_Reference
10477 and then Attribute_Name (Subt) = Name_Class
10479 return Names_T (Prefix (Subt));
10490 function Mentions_T (Acc_Def : Node_Id) return Boolean is
10491 Param_Spec : Node_Id;
10493 Acc_Subprg : constant Node_Id :=
10494 Access_To_Subprogram_Definition (Acc_Def);
10497 if No (Acc_Subprg) then
10498 return Designates_T (Subtype_Mark (Acc_Def));
10501 -- Component is an access_to_subprogram: examine its formals,
10502 -- and result definition in the case of an access_to_function.
10504 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
10505 while Present (Param_Spec) loop
10506 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
10507 and then Mentions_T (Parameter_Type (Param_Spec))
10511 elsif Designates_T (Parameter_Type (Param_Spec)) then
10518 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
10519 if Nkind (Result_Definition (Acc_Subprg)) =
10520 N_Access_Definition
10522 return Mentions_T (Result_Definition (Acc_Subprg));
10524 return Designates_T (Result_Definition (Acc_Subprg));
10531 -- Start of processing for Check_Anonymous_Access_Components
10534 if No (Comp_List) then
10538 Comp := First (Component_Items (Comp_List));
10539 while Present (Comp) loop
10540 if Nkind (Comp) = N_Component_Declaration
10542 (Access_Definition (Component_Definition (Comp)))
10544 Mentions_T (Access_Definition (Component_Definition (Comp)))
10546 Comp_Def := Component_Definition (Comp);
10548 Access_To_Subprogram_Definition (Access_Definition (Comp_Def));
10550 Build_Incomplete_Type_Declaration;
10551 Anon_Access := Make_Temporary (Loc, 'S');
10553 -- Create a declaration for the anonymous access type: either
10554 -- an access_to_object or an access_to_subprogram.
10556 if Present (Acc_Def) then
10557 if Nkind (Acc_Def) = N_Access_Function_Definition then
10559 Make_Access_Function_Definition (Loc,
10560 Parameter_Specifications =>
10561 Parameter_Specifications (Acc_Def),
10562 Result_Definition => Result_Definition (Acc_Def));
10565 Make_Access_Procedure_Definition (Loc,
10566 Parameter_Specifications =>
10567 Parameter_Specifications (Acc_Def));
10572 Make_Access_To_Object_Definition (Loc,
10573 Subtype_Indication =>
10575 (Subtype_Mark (Access_Definition (Comp_Def))));
10577 Set_Constant_Present
10578 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
10580 (Type_Def, All_Present (Access_Definition (Comp_Def)));
10583 Set_Null_Exclusion_Present
10585 Null_Exclusion_Present (Access_Definition (Comp_Def)));
10588 Make_Full_Type_Declaration (Loc,
10589 Defining_Identifier => Anon_Access,
10590 Type_Definition => Type_Def);
10592 Insert_Before (Typ_Decl, Decl);
10595 -- If an access to subprogram, create the extra formals
10597 if Present (Acc_Def) then
10598 Create_Extra_Formals (Designated_Type (Anon_Access));
10600 -- If an access to object, preserve entity of designated type,
10601 -- for ASIS use, before rewriting the component definition.
10608 Desig := Entity (Subtype_Indication (Type_Def));
10610 -- If the access definition is to the current record,
10611 -- the visible entity at this point is an incomplete
10612 -- type. Retrieve the full view to simplify ASIS queries
10614 if Ekind (Desig) = E_Incomplete_Type then
10615 Desig := Full_View (Desig);
10619 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
10624 Make_Component_Definition (Loc,
10625 Subtype_Indication =>
10626 New_Occurrence_Of (Anon_Access, Loc)));
10628 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
10629 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
10631 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
10634 Set_Is_Local_Anonymous_Access (Anon_Access);
10640 if Present (Variant_Part (Comp_List)) then
10644 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
10645 while Present (V) loop
10646 Check_Anonymous_Access_Components
10647 (Typ_Decl, Typ, Prev, Component_List (V));
10648 Next_Non_Pragma (V);
10652 end Check_Anonymous_Access_Components;
10654 ----------------------
10655 -- Check_Completion --
10656 ----------------------
10658 procedure Check_Completion (Body_Id : Node_Id := Empty) is
10661 procedure Post_Error;
10662 -- Post error message for lack of completion for entity E
10668 procedure Post_Error is
10670 procedure Missing_Body;
10671 -- Output missing body message
10677 procedure Missing_Body is
10679 -- Spec is in same unit, so we can post on spec
10681 if In_Same_Source_Unit (Body_Id, E) then
10682 Error_Msg_N ("missing body for &", E);
10684 -- Spec is in a separate unit, so we have to post on the body
10687 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
10691 -- Start of processing for Post_Error
10694 if not Comes_From_Source (E) then
10696 if Ekind_In (E, E_Task_Type, E_Protected_Type) then
10698 -- It may be an anonymous protected type created for a
10699 -- single variable. Post error on variable, if present.
10705 Var := First_Entity (Current_Scope);
10706 while Present (Var) loop
10707 exit when Etype (Var) = E
10708 and then Comes_From_Source (Var);
10713 if Present (Var) then
10720 -- If a generated entity has no completion, then either previous
10721 -- semantic errors have disabled the expansion phase, or else we had
10722 -- missing subunits, or else we are compiling without expansion,
10723 -- or else something is very wrong.
10725 if not Comes_From_Source (E) then
10727 (Serious_Errors_Detected > 0
10728 or else Configurable_Run_Time_Violations > 0
10729 or else Subunits_Missing
10730 or else not Expander_Active);
10733 -- Here for source entity
10736 -- Here if no body to post the error message, so we post the error
10737 -- on the declaration that has no completion. This is not really
10738 -- the right place to post it, think about this later ???
10740 if No (Body_Id) then
10741 if Is_Type (E) then
10743 ("missing full declaration for }", Parent (E), E);
10745 Error_Msg_NE ("missing body for &", Parent (E), E);
10748 -- Package body has no completion for a declaration that appears
10749 -- in the corresponding spec. Post error on the body, with a
10750 -- reference to the non-completed declaration.
10753 Error_Msg_Sloc := Sloc (E);
10755 if Is_Type (E) then
10756 Error_Msg_NE ("missing full declaration for }!", Body_Id, E);
10758 elsif Is_Overloadable (E)
10759 and then Current_Entity_In_Scope (E) /= E
10761 -- It may be that the completion is mistyped and appears as
10762 -- a distinct overloading of the entity.
10765 Candidate : constant Entity_Id :=
10766 Current_Entity_In_Scope (E);
10767 Decl : constant Node_Id :=
10768 Unit_Declaration_Node (Candidate);
10771 if Is_Overloadable (Candidate)
10772 and then Ekind (Candidate) = Ekind (E)
10773 and then Nkind (Decl) = N_Subprogram_Body
10774 and then Acts_As_Spec (Decl)
10776 Check_Type_Conformant (Candidate, E);
10792 Pack_Id : constant Entity_Id := Current_Scope;
10794 -- Start of processing for Check_Completion
10797 E := First_Entity (Pack_Id);
10798 while Present (E) loop
10799 if Is_Intrinsic_Subprogram (E) then
10802 -- A Ghost entity declared in a non-Ghost package does not force the
10803 -- need for a body (SPARK RM 6.9(11)).
10805 elsif not Is_Ghost_Entity (Pack_Id) and then Is_Ghost_Entity (E) then
10808 -- The following situation requires special handling: a child unit
10809 -- that appears in the context clause of the body of its parent:
10811 -- procedure Parent.Child (...);
10813 -- with Parent.Child;
10814 -- package body Parent is
10816 -- Here Parent.Child appears as a local entity, but should not be
10817 -- flagged as requiring completion, because it is a compilation
10820 -- Ignore missing completion for a subprogram that does not come from
10821 -- source (including the _Call primitive operation of RAS types,
10822 -- which has to have the flag Comes_From_Source for other purposes):
10823 -- we assume that the expander will provide the missing completion.
10824 -- In case of previous errors, other expansion actions that provide
10825 -- bodies for null procedures with not be invoked, so inhibit message
10828 -- Note that E_Operator is not in the list that follows, because
10829 -- this kind is reserved for predefined operators, that are
10830 -- intrinsic and do not need completion.
10832 elsif Ekind_In (E, E_Function,
10834 E_Generic_Function,
10835 E_Generic_Procedure)
10837 if Has_Completion (E) then
10840 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
10843 elsif Is_Subprogram (E)
10844 and then (not Comes_From_Source (E)
10845 or else Chars (E) = Name_uCall)
10850 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
10854 elsif Nkind (Parent (E)) = N_Procedure_Specification
10855 and then Null_Present (Parent (E))
10856 and then Serious_Errors_Detected > 0
10864 elsif Is_Entry (E) then
10865 if not Has_Completion (E) and then
10866 (Ekind (Scope (E)) = E_Protected_Object
10867 or else Ekind (Scope (E)) = E_Protected_Type)
10872 elsif Is_Package_Or_Generic_Package (E) then
10873 if Unit_Requires_Body (E) then
10874 if not Has_Completion (E)
10875 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
10881 elsif not Is_Child_Unit (E) then
10882 May_Need_Implicit_Body (E);
10885 -- A formal incomplete type (Ada 2012) does not require a completion;
10886 -- other incomplete type declarations do.
10888 elsif Ekind (E) = E_Incomplete_Type
10889 and then No (Underlying_Type (E))
10890 and then not Is_Generic_Type (E)
10894 elsif Ekind_In (E, E_Task_Type, E_Protected_Type)
10895 and then not Has_Completion (E)
10899 -- A single task declared in the current scope is a constant, verify
10900 -- that the body of its anonymous type is in the same scope. If the
10901 -- task is defined elsewhere, this may be a renaming declaration for
10902 -- which no completion is needed.
10904 elsif Ekind (E) = E_Constant
10905 and then Ekind (Etype (E)) = E_Task_Type
10906 and then not Has_Completion (Etype (E))
10907 and then Scope (Etype (E)) = Current_Scope
10911 elsif Ekind (E) = E_Protected_Object
10912 and then not Has_Completion (Etype (E))
10916 elsif Ekind (E) = E_Record_Type then
10917 if Is_Tagged_Type (E) then
10918 Check_Abstract_Overriding (E);
10919 Check_Conventions (E);
10922 Check_Aliased_Component_Types (E);
10924 elsif Ekind (E) = E_Array_Type then
10925 Check_Aliased_Component_Types (E);
10931 end Check_Completion;
10933 ------------------------------------
10934 -- Check_CPP_Type_Has_No_Defaults --
10935 ------------------------------------
10937 procedure Check_CPP_Type_Has_No_Defaults (T : Entity_Id) is
10938 Tdef : constant Node_Id := Type_Definition (Declaration_Node (T));
10943 -- Obtain the component list
10945 if Nkind (Tdef) = N_Record_Definition then
10946 Clist := Component_List (Tdef);
10947 else pragma Assert (Nkind (Tdef) = N_Derived_Type_Definition);
10948 Clist := Component_List (Record_Extension_Part (Tdef));
10951 -- Check all components to ensure no default expressions
10953 if Present (Clist) then
10954 Comp := First (Component_Items (Clist));
10955 while Present (Comp) loop
10956 if Present (Expression (Comp)) then
10958 ("component of imported 'C'P'P type cannot have "
10959 & "default expression", Expression (Comp));
10965 end Check_CPP_Type_Has_No_Defaults;
10967 ----------------------------
10968 -- Check_Delta_Expression --
10969 ----------------------------
10971 procedure Check_Delta_Expression (E : Node_Id) is
10973 if not (Is_Real_Type (Etype (E))) then
10974 Wrong_Type (E, Any_Real);
10976 elsif not Is_OK_Static_Expression (E) then
10977 Flag_Non_Static_Expr
10978 ("non-static expression used for delta value!", E);
10980 elsif not UR_Is_Positive (Expr_Value_R (E)) then
10981 Error_Msg_N ("delta expression must be positive", E);
10987 -- If any of above errors occurred, then replace the incorrect
10988 -- expression by the real 0.1, which should prevent further errors.
10991 Make_Real_Literal (Sloc (E), Ureal_Tenth));
10992 Analyze_And_Resolve (E, Standard_Float);
10993 end Check_Delta_Expression;
10995 -----------------------------
10996 -- Check_Digits_Expression --
10997 -----------------------------
10999 procedure Check_Digits_Expression (E : Node_Id) is
11001 if not (Is_Integer_Type (Etype (E))) then
11002 Wrong_Type (E, Any_Integer);
11004 elsif not Is_OK_Static_Expression (E) then
11005 Flag_Non_Static_Expr
11006 ("non-static expression used for digits value!", E);
11008 elsif Expr_Value (E) <= 0 then
11009 Error_Msg_N ("digits value must be greater than zero", E);
11015 -- If any of above errors occurred, then replace the incorrect
11016 -- expression by the integer 1, which should prevent further errors.
11018 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
11019 Analyze_And_Resolve (E, Standard_Integer);
11021 end Check_Digits_Expression;
11023 --------------------------
11024 -- Check_Initialization --
11025 --------------------------
11027 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
11029 -- Special processing for limited types
11031 if Is_Limited_Type (T)
11032 and then not In_Instance
11033 and then not In_Inlined_Body
11035 if not OK_For_Limited_Init (T, Exp) then
11037 -- In GNAT mode, this is just a warning, to allow it to be evilly
11038 -- turned off. Otherwise it is a real error.
11042 ("??cannot initialize entities of limited type!", Exp);
11044 elsif Ada_Version < Ada_2005 then
11046 -- The side effect removal machinery may generate illegal Ada
11047 -- code to avoid the usage of access types and 'reference in
11048 -- SPARK mode. Since this is legal code with respect to theorem
11049 -- proving, do not emit the error.
11052 and then Nkind (Exp) = N_Function_Call
11053 and then Nkind (Parent (Exp)) = N_Object_Declaration
11054 and then not Comes_From_Source
11055 (Defining_Identifier (Parent (Exp)))
11061 ("cannot initialize entities of limited type", Exp);
11062 Explain_Limited_Type (T, Exp);
11066 -- Specialize error message according to kind of illegal
11067 -- initial expression.
11069 if Nkind (Exp) = N_Type_Conversion
11070 and then Nkind (Expression (Exp)) = N_Function_Call
11073 ("illegal context for call"
11074 & " to function with limited result", Exp);
11078 ("initialization of limited object requires aggregate "
11079 & "or function call", Exp);
11085 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag gets
11086 -- set unless we can be sure that no range check is required.
11088 if (GNATprove_Mode or not Expander_Active)
11089 and then Is_Scalar_Type (T)
11090 and then not Is_In_Range (Exp, T, Assume_Valid => True)
11092 Set_Do_Range_Check (Exp);
11094 end Check_Initialization;
11096 ----------------------
11097 -- Check_Interfaces --
11098 ----------------------
11100 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
11101 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
11104 Iface_Def : Node_Id;
11105 Iface_Typ : Entity_Id;
11106 Parent_Node : Node_Id;
11108 Is_Task : Boolean := False;
11109 -- Set True if parent type or any progenitor is a task interface
11111 Is_Protected : Boolean := False;
11112 -- Set True if parent type or any progenitor is a protected interface
11114 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
11115 -- Check that a progenitor is compatible with declaration. If an error
11116 -- message is output, it is posted on Error_Node.
11122 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
11123 Iface_Id : constant Entity_Id :=
11124 Defining_Identifier (Parent (Iface_Def));
11125 Type_Def : Node_Id;
11128 if Nkind (N) = N_Private_Extension_Declaration then
11131 Type_Def := Type_Definition (N);
11134 if Is_Task_Interface (Iface_Id) then
11137 elsif Is_Protected_Interface (Iface_Id) then
11138 Is_Protected := True;
11141 if Is_Synchronized_Interface (Iface_Id) then
11143 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
11144 -- extension derived from a synchronized interface must explicitly
11145 -- be declared synchronized, because the full view will be a
11146 -- synchronized type.
11148 if Nkind (N) = N_Private_Extension_Declaration then
11149 if not Synchronized_Present (N) then
11151 ("private extension of& must be explicitly synchronized",
11155 -- However, by 3.9.4(16/2), a full type that is a record extension
11156 -- is never allowed to derive from a synchronized interface (note
11157 -- that interfaces must be excluded from this check, because those
11158 -- are represented by derived type definitions in some cases).
11160 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11161 and then not Interface_Present (Type_Definition (N))
11163 Error_Msg_N ("record extension cannot derive from synchronized "
11164 & "interface", Error_Node);
11168 -- Check that the characteristics of the progenitor are compatible
11169 -- with the explicit qualifier in the declaration.
11170 -- The check only applies to qualifiers that come from source.
11171 -- Limited_Present also appears in the declaration of corresponding
11172 -- records, and the check does not apply to them.
11174 if Limited_Present (Type_Def)
11176 Is_Concurrent_Record_Type (Defining_Identifier (N))
11178 if Is_Limited_Interface (Parent_Type)
11179 and then not Is_Limited_Interface (Iface_Id)
11182 ("progenitor & must be limited interface",
11183 Error_Node, Iface_Id);
11186 (Task_Present (Iface_Def)
11187 or else Protected_Present (Iface_Def)
11188 or else Synchronized_Present (Iface_Def))
11189 and then Nkind (N) /= N_Private_Extension_Declaration
11190 and then not Error_Posted (N)
11193 ("progenitor & must be limited interface",
11194 Error_Node, Iface_Id);
11197 -- Protected interfaces can only inherit from limited, synchronized
11198 -- or protected interfaces.
11200 elsif Nkind (N) = N_Full_Type_Declaration
11201 and then Protected_Present (Type_Def)
11203 if Limited_Present (Iface_Def)
11204 or else Synchronized_Present (Iface_Def)
11205 or else Protected_Present (Iface_Def)
11209 elsif Task_Present (Iface_Def) then
11210 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11211 & "from task interface", Error_Node);
11214 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11215 & "from non-limited interface", Error_Node);
11218 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
11219 -- limited and synchronized.
11221 elsif Synchronized_Present (Type_Def) then
11222 if Limited_Present (Iface_Def)
11223 or else Synchronized_Present (Iface_Def)
11227 elsif Protected_Present (Iface_Def)
11228 and then Nkind (N) /= N_Private_Extension_Declaration
11230 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11231 & "from protected interface", Error_Node);
11233 elsif Task_Present (Iface_Def)
11234 and then Nkind (N) /= N_Private_Extension_Declaration
11236 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11237 & "from task interface", Error_Node);
11239 elsif not Is_Limited_Interface (Iface_Id) then
11240 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11241 & "from non-limited interface", Error_Node);
11244 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
11245 -- synchronized or task interfaces.
11247 elsif Nkind (N) = N_Full_Type_Declaration
11248 and then Task_Present (Type_Def)
11250 if Limited_Present (Iface_Def)
11251 or else Synchronized_Present (Iface_Def)
11252 or else Task_Present (Iface_Def)
11256 elsif Protected_Present (Iface_Def) then
11257 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11258 & "protected interface", Error_Node);
11261 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11262 & "non-limited interface", Error_Node);
11267 -- Start of processing for Check_Interfaces
11270 if Is_Interface (Parent_Type) then
11271 if Is_Task_Interface (Parent_Type) then
11274 elsif Is_Protected_Interface (Parent_Type) then
11275 Is_Protected := True;
11279 if Nkind (N) = N_Private_Extension_Declaration then
11281 -- Check that progenitors are compatible with declaration
11283 Iface := First (Interface_List (Def));
11284 while Present (Iface) loop
11285 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11287 Parent_Node := Parent (Base_Type (Iface_Typ));
11288 Iface_Def := Type_Definition (Parent_Node);
11290 if not Is_Interface (Iface_Typ) then
11291 Diagnose_Interface (Iface, Iface_Typ);
11293 Check_Ifaces (Iface_Def, Iface);
11299 if Is_Task and Is_Protected then
11301 ("type cannot derive from task and protected interface", N);
11307 -- Full type declaration of derived type.
11308 -- Check compatibility with parent if it is interface type
11310 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11311 and then Is_Interface (Parent_Type)
11313 Parent_Node := Parent (Parent_Type);
11315 -- More detailed checks for interface varieties
11318 (Iface_Def => Type_Definition (Parent_Node),
11319 Error_Node => Subtype_Indication (Type_Definition (N)));
11322 Iface := First (Interface_List (Def));
11323 while Present (Iface) loop
11324 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11326 Parent_Node := Parent (Base_Type (Iface_Typ));
11327 Iface_Def := Type_Definition (Parent_Node);
11329 if not Is_Interface (Iface_Typ) then
11330 Diagnose_Interface (Iface, Iface_Typ);
11333 -- "The declaration of a specific descendant of an interface
11334 -- type freezes the interface type" RM 13.14
11336 Freeze_Before (N, Iface_Typ);
11337 Check_Ifaces (Iface_Def, Error_Node => Iface);
11343 if Is_Task and Is_Protected then
11345 ("type cannot derive from task and protected interface", N);
11347 end Check_Interfaces;
11349 ------------------------------------
11350 -- Check_Or_Process_Discriminants --
11351 ------------------------------------
11353 -- If an incomplete or private type declaration was already given for the
11354 -- type, the discriminants may have already been processed if they were
11355 -- present on the incomplete declaration. In this case a full conformance
11356 -- check has been performed in Find_Type_Name, and we then recheck here
11357 -- some properties that can't be checked on the partial view alone.
11358 -- Otherwise we call Process_Discriminants.
11360 procedure Check_Or_Process_Discriminants
11363 Prev : Entity_Id := Empty)
11366 if Has_Discriminants (T) then
11368 -- Discriminants are already set on T if they were already present
11369 -- on the partial view. Make them visible to component declarations.
11373 -- Discriminant on T (full view) referencing expr on partial view
11375 Prev_D : Entity_Id;
11376 -- Entity of corresponding discriminant on partial view
11379 -- Discriminant specification for full view, expression is
11380 -- the syntactic copy on full view (which has been checked for
11381 -- conformance with partial view), only used here to post error
11385 D := First_Discriminant (T);
11386 New_D := First (Discriminant_Specifications (N));
11387 while Present (D) loop
11388 Prev_D := Current_Entity (D);
11389 Set_Current_Entity (D);
11390 Set_Is_Immediately_Visible (D);
11391 Set_Homonym (D, Prev_D);
11393 -- Handle the case where there is an untagged partial view and
11394 -- the full view is tagged: must disallow discriminants with
11395 -- defaults, unless compiling for Ada 2012, which allows a
11396 -- limited tagged type to have defaulted discriminants (see
11397 -- AI05-0214). However, suppress error here if it was already
11398 -- reported on the default expression of the partial view.
11400 if Is_Tagged_Type (T)
11401 and then Present (Expression (Parent (D)))
11402 and then (not Is_Limited_Type (Current_Scope)
11403 or else Ada_Version < Ada_2012)
11404 and then not Error_Posted (Expression (Parent (D)))
11406 if Ada_Version >= Ada_2012 then
11408 ("discriminants of nonlimited tagged type cannot have "
11410 Expression (New_D));
11413 ("discriminants of tagged type cannot have defaults",
11414 Expression (New_D));
11418 -- Ada 2005 (AI-230): Access discriminant allowed in
11419 -- non-limited record types.
11421 if Ada_Version < Ada_2005 then
11423 -- This restriction gets applied to the full type here. It
11424 -- has already been applied earlier to the partial view.
11426 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
11429 Next_Discriminant (D);
11434 elsif Present (Discriminant_Specifications (N)) then
11435 Process_Discriminants (N, Prev);
11437 end Check_Or_Process_Discriminants;
11439 ----------------------
11440 -- Check_Real_Bound --
11441 ----------------------
11443 procedure Check_Real_Bound (Bound : Node_Id) is
11445 if not Is_Real_Type (Etype (Bound)) then
11447 ("bound in real type definition must be of real type", Bound);
11449 elsif not Is_OK_Static_Expression (Bound) then
11450 Flag_Non_Static_Expr
11451 ("non-static expression used for real type bound!", Bound);
11458 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
11460 Resolve (Bound, Standard_Float);
11461 end Check_Real_Bound;
11463 ------------------------------
11464 -- Complete_Private_Subtype --
11465 ------------------------------
11467 procedure Complete_Private_Subtype
11470 Full_Base : Entity_Id;
11471 Related_Nod : Node_Id)
11473 Save_Next_Entity : Entity_Id;
11474 Save_Homonym : Entity_Id;
11477 -- Set semantic attributes for (implicit) private subtype completion.
11478 -- If the full type has no discriminants, then it is a copy of the
11479 -- full view of the base. Otherwise, it is a subtype of the base with
11480 -- a possible discriminant constraint. Save and restore the original
11481 -- Next_Entity field of full to ensure that the calls to Copy_Node do
11482 -- not corrupt the entity chain.
11484 -- Note that the type of the full view is the same entity as the type
11485 -- of the partial view. In this fashion, the subtype has access to the
11486 -- correct view of the parent.
11488 Save_Next_Entity := Next_Entity (Full);
11489 Save_Homonym := Homonym (Priv);
11491 case Ekind (Full_Base) is
11492 when E_Record_Type |
11498 Copy_Node (Priv, Full);
11500 Set_Has_Discriminants
11501 (Full, Has_Discriminants (Full_Base));
11502 Set_Has_Unknown_Discriminants
11503 (Full, Has_Unknown_Discriminants (Full_Base));
11504 Set_First_Entity (Full, First_Entity (Full_Base));
11505 Set_Last_Entity (Full, Last_Entity (Full_Base));
11507 -- If the underlying base type is constrained, we know that the
11508 -- full view of the subtype is constrained as well (the converse
11509 -- is not necessarily true).
11511 if Is_Constrained (Full_Base) then
11512 Set_Is_Constrained (Full);
11516 Copy_Node (Full_Base, Full);
11518 Set_Chars (Full, Chars (Priv));
11519 Conditional_Delay (Full, Priv);
11520 Set_Sloc (Full, Sloc (Priv));
11523 Set_Next_Entity (Full, Save_Next_Entity);
11524 Set_Homonym (Full, Save_Homonym);
11525 Set_Associated_Node_For_Itype (Full, Related_Nod);
11527 -- Set common attributes for all subtypes: kind, convention, etc.
11529 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
11530 Set_Convention (Full, Convention (Full_Base));
11532 -- The Etype of the full view is inconsistent. Gigi needs to see the
11533 -- structural full view, which is what the current scheme gives: the
11534 -- Etype of the full view is the etype of the full base. However, if the
11535 -- full base is a derived type, the full view then looks like a subtype
11536 -- of the parent, not a subtype of the full base. If instead we write:
11538 -- Set_Etype (Full, Full_Base);
11540 -- then we get inconsistencies in the front-end (confusion between
11541 -- views). Several outstanding bugs are related to this ???
11543 Set_Is_First_Subtype (Full, False);
11544 Set_Scope (Full, Scope (Priv));
11545 Set_Size_Info (Full, Full_Base);
11546 Set_RM_Size (Full, RM_Size (Full_Base));
11547 Set_Is_Itype (Full);
11549 -- A subtype of a private-type-without-discriminants, whose full-view
11550 -- has discriminants with default expressions, is not constrained.
11552 if not Has_Discriminants (Priv) then
11553 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
11555 if Has_Discriminants (Full_Base) then
11556 Set_Discriminant_Constraint
11557 (Full, Discriminant_Constraint (Full_Base));
11559 -- The partial view may have been indefinite, the full view
11562 Set_Has_Unknown_Discriminants
11563 (Full, Has_Unknown_Discriminants (Full_Base));
11567 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
11568 Set_Depends_On_Private (Full, Has_Private_Component (Full));
11570 -- Freeze the private subtype entity if its parent is delayed, and not
11571 -- already frozen. We skip this processing if the type is an anonymous
11572 -- subtype of a record component, or is the corresponding record of a
11573 -- protected type, since ???
11575 if not Is_Type (Scope (Full)) then
11576 Set_Has_Delayed_Freeze (Full,
11577 Has_Delayed_Freeze (Full_Base)
11578 and then (not Is_Frozen (Full_Base)));
11581 Set_Freeze_Node (Full, Empty);
11582 Set_Is_Frozen (Full, False);
11583 Set_Full_View (Priv, Full);
11585 if Has_Discriminants (Full) then
11586 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
11587 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
11589 if Has_Unknown_Discriminants (Full) then
11590 Set_Discriminant_Constraint (Full, No_Elist);
11594 if Ekind (Full_Base) = E_Record_Type
11595 and then Has_Discriminants (Full_Base)
11596 and then Has_Discriminants (Priv) -- might not, if errors
11597 and then not Has_Unknown_Discriminants (Priv)
11598 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
11600 Create_Constrained_Components
11601 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
11603 -- If the full base is itself derived from private, build a congruent
11604 -- subtype of its underlying type, for use by the back end. For a
11605 -- constrained record component, the declaration cannot be placed on
11606 -- the component list, but it must nevertheless be built an analyzed, to
11607 -- supply enough information for Gigi to compute the size of component.
11609 elsif Ekind (Full_Base) in Private_Kind
11610 and then Is_Derived_Type (Full_Base)
11611 and then Has_Discriminants (Full_Base)
11612 and then (Ekind (Current_Scope) /= E_Record_Subtype)
11614 if not Is_Itype (Priv)
11616 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
11618 Build_Underlying_Full_View
11619 (Parent (Priv), Full, Etype (Full_Base));
11621 elsif Nkind (Related_Nod) = N_Component_Declaration then
11622 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
11625 elsif Is_Record_Type (Full_Base) then
11627 -- Show Full is simply a renaming of Full_Base
11629 Set_Cloned_Subtype (Full, Full_Base);
11632 -- It is unsafe to share the bounds of a scalar type, because the Itype
11633 -- is elaborated on demand, and if a bound is non-static then different
11634 -- orders of elaboration in different units will lead to different
11635 -- external symbols.
11637 if Is_Scalar_Type (Full_Base) then
11638 Set_Scalar_Range (Full,
11639 Make_Range (Sloc (Related_Nod),
11641 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
11643 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
11645 -- This completion inherits the bounds of the full parent, but if
11646 -- the parent is an unconstrained floating point type, so is the
11649 if Is_Floating_Point_Type (Full_Base) then
11650 Set_Includes_Infinities
11651 (Scalar_Range (Full), Has_Infinities (Full_Base));
11655 -- ??? It seems that a lot of fields are missing that should be copied
11656 -- from Full_Base to Full. Here are some that are introduced in a
11657 -- non-disruptive way but a cleanup is necessary.
11659 if Is_Tagged_Type (Full_Base) then
11660 Set_Is_Tagged_Type (Full);
11661 Set_Direct_Primitive_Operations
11662 (Full, Direct_Primitive_Operations (Full_Base));
11663 Set_No_Tagged_Streams_Pragma
11664 (Full, No_Tagged_Streams_Pragma (Full_Base));
11666 -- Inherit class_wide type of full_base in case the partial view was
11667 -- not tagged. Otherwise it has already been created when the private
11668 -- subtype was analyzed.
11670 if No (Class_Wide_Type (Full)) then
11671 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
11674 -- If this is a subtype of a protected or task type, constrain its
11675 -- corresponding record, unless this is a subtype without constraints,
11676 -- i.e. a simple renaming as with an actual subtype in an instance.
11678 elsif Is_Concurrent_Type (Full_Base) then
11679 if Has_Discriminants (Full)
11680 and then Present (Corresponding_Record_Type (Full_Base))
11682 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
11684 Set_Corresponding_Record_Type (Full,
11685 Constrain_Corresponding_Record
11686 (Full, Corresponding_Record_Type (Full_Base), Related_Nod));
11689 Set_Corresponding_Record_Type (Full,
11690 Corresponding_Record_Type (Full_Base));
11694 -- Link rep item chain, and also setting of Has_Predicates from private
11695 -- subtype to full subtype, since we will need these on the full subtype
11696 -- to create the predicate function. Note that the full subtype may
11697 -- already have rep items, inherited from the full view of the base
11698 -- type, so we must be sure not to overwrite these entries.
11703 Next_Item : Node_Id;
11706 Item := First_Rep_Item (Full);
11708 -- If no existing rep items on full type, we can just link directly
11709 -- to the list of items on the private type, if any exist.. Same if
11710 -- the rep items are only those inherited from the base
11713 or else Nkind (Item) /= N_Aspect_Specification
11714 or else Entity (Item) = Full_Base)
11715 and then Present (First_Rep_Item (Priv))
11717 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
11719 -- Otherwise, search to the end of items currently linked to the full
11720 -- subtype and append the private items to the end. However, if Priv
11721 -- and Full already have the same list of rep items, then the append
11722 -- is not done, as that would create a circularity.
11724 elsif Item /= First_Rep_Item (Priv) then
11727 Next_Item := Next_Rep_Item (Item);
11728 exit when No (Next_Item);
11731 -- If the private view has aspect specifications, the full view
11732 -- inherits them. Since these aspects may already have been
11733 -- attached to the full view during derivation, do not append
11734 -- them if already present.
11736 if Item = First_Rep_Item (Priv) then
11742 -- And link the private type items at the end of the chain
11745 Set_Next_Rep_Item (Item, First_Rep_Item (Priv));
11750 -- Make sure Has_Predicates is set on full type if it is set on the
11751 -- private type. Note that it may already be set on the full type and
11752 -- if so, we don't want to unset it.
11754 if Has_Predicates (Priv) then
11755 Set_Has_Predicates (Full);
11757 end Complete_Private_Subtype;
11759 ----------------------------
11760 -- Constant_Redeclaration --
11761 ----------------------------
11763 procedure Constant_Redeclaration
11768 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
11769 Obj_Def : constant Node_Id := Object_Definition (N);
11772 procedure Check_Possible_Deferred_Completion
11773 (Prev_Id : Entity_Id;
11774 Prev_Obj_Def : Node_Id;
11775 Curr_Obj_Def : Node_Id);
11776 -- Determine whether the two object definitions describe the partial
11777 -- and the full view of a constrained deferred constant. Generate
11778 -- a subtype for the full view and verify that it statically matches
11779 -- the subtype of the partial view.
11781 procedure Check_Recursive_Declaration (Typ : Entity_Id);
11782 -- If deferred constant is an access type initialized with an allocator,
11783 -- check whether there is an illegal recursion in the definition,
11784 -- through a default value of some record subcomponent. This is normally
11785 -- detected when generating init procs, but requires this additional
11786 -- mechanism when expansion is disabled.
11788 ----------------------------------------
11789 -- Check_Possible_Deferred_Completion --
11790 ----------------------------------------
11792 procedure Check_Possible_Deferred_Completion
11793 (Prev_Id : Entity_Id;
11794 Prev_Obj_Def : Node_Id;
11795 Curr_Obj_Def : Node_Id)
11798 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
11799 and then Present (Constraint (Prev_Obj_Def))
11800 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
11801 and then Present (Constraint (Curr_Obj_Def))
11804 Loc : constant Source_Ptr := Sloc (N);
11805 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'S');
11806 Decl : constant Node_Id :=
11807 Make_Subtype_Declaration (Loc,
11808 Defining_Identifier => Def_Id,
11809 Subtype_Indication =>
11810 Relocate_Node (Curr_Obj_Def));
11813 Insert_Before_And_Analyze (N, Decl);
11814 Set_Etype (Id, Def_Id);
11816 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
11817 Error_Msg_Sloc := Sloc (Prev_Id);
11818 Error_Msg_N ("subtype does not statically match deferred "
11819 & "declaration #", N);
11823 end Check_Possible_Deferred_Completion;
11825 ---------------------------------
11826 -- Check_Recursive_Declaration --
11827 ---------------------------------
11829 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
11833 if Is_Record_Type (Typ) then
11834 Comp := First_Component (Typ);
11835 while Present (Comp) loop
11836 if Comes_From_Source (Comp) then
11837 if Present (Expression (Parent (Comp)))
11838 and then Is_Entity_Name (Expression (Parent (Comp)))
11839 and then Entity (Expression (Parent (Comp))) = Prev
11841 Error_Msg_Sloc := Sloc (Parent (Comp));
11843 ("illegal circularity with declaration for & #",
11847 elsif Is_Record_Type (Etype (Comp)) then
11848 Check_Recursive_Declaration (Etype (Comp));
11852 Next_Component (Comp);
11855 end Check_Recursive_Declaration;
11857 -- Start of processing for Constant_Redeclaration
11860 if Nkind (Parent (Prev)) = N_Object_Declaration then
11861 if Nkind (Object_Definition
11862 (Parent (Prev))) = N_Subtype_Indication
11864 -- Find type of new declaration. The constraints of the two
11865 -- views must match statically, but there is no point in
11866 -- creating an itype for the full view.
11868 if Nkind (Obj_Def) = N_Subtype_Indication then
11869 Find_Type (Subtype_Mark (Obj_Def));
11870 New_T := Entity (Subtype_Mark (Obj_Def));
11873 Find_Type (Obj_Def);
11874 New_T := Entity (Obj_Def);
11880 -- The full view may impose a constraint, even if the partial
11881 -- view does not, so construct the subtype.
11883 New_T := Find_Type_Of_Object (Obj_Def, N);
11888 -- Current declaration is illegal, diagnosed below in Enter_Name
11894 -- If previous full declaration or a renaming declaration exists, or if
11895 -- a homograph is present, let Enter_Name handle it, either with an
11896 -- error or with the removal of an overridden implicit subprogram.
11897 -- The previous one is a full declaration if it has an expression
11898 -- (which in the case of an aggregate is indicated by the Init flag).
11900 if Ekind (Prev) /= E_Constant
11901 or else Nkind (Parent (Prev)) = N_Object_Renaming_Declaration
11902 or else Present (Expression (Parent (Prev)))
11903 or else Has_Init_Expression (Parent (Prev))
11904 or else Present (Full_View (Prev))
11908 -- Verify that types of both declarations match, or else that both types
11909 -- are anonymous access types whose designated subtypes statically match
11910 -- (as allowed in Ada 2005 by AI-385).
11912 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
11914 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
11915 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
11916 or else Is_Access_Constant (Etype (New_T)) /=
11917 Is_Access_Constant (Etype (Prev))
11918 or else Can_Never_Be_Null (Etype (New_T)) /=
11919 Can_Never_Be_Null (Etype (Prev))
11920 or else Null_Exclusion_Present (Parent (Prev)) /=
11921 Null_Exclusion_Present (Parent (Id))
11922 or else not Subtypes_Statically_Match
11923 (Designated_Type (Etype (Prev)),
11924 Designated_Type (Etype (New_T))))
11926 Error_Msg_Sloc := Sloc (Prev);
11927 Error_Msg_N ("type does not match declaration#", N);
11928 Set_Full_View (Prev, Id);
11929 Set_Etype (Id, Any_Type);
11931 -- A deferred constant whose type is an anonymous array is always
11932 -- illegal (unless imported). A detailed error message might be
11933 -- helpful for Ada beginners.
11935 if Nkind (Object_Definition (Parent (Prev)))
11936 = N_Constrained_Array_Definition
11937 and then Nkind (Object_Definition (N))
11938 = N_Constrained_Array_Definition
11940 Error_Msg_N ("\each anonymous array is a distinct type", N);
11941 Error_Msg_N ("a deferred constant must have a named type",
11942 Object_Definition (Parent (Prev)));
11946 Null_Exclusion_Present (Parent (Prev))
11947 and then not Null_Exclusion_Present (N)
11949 Error_Msg_Sloc := Sloc (Prev);
11950 Error_Msg_N ("null-exclusion does not match declaration#", N);
11951 Set_Full_View (Prev, Id);
11952 Set_Etype (Id, Any_Type);
11954 -- If so, process the full constant declaration
11957 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
11958 -- the deferred declaration is constrained, then the subtype defined
11959 -- by the subtype_indication in the full declaration shall match it
11962 Check_Possible_Deferred_Completion
11964 Prev_Obj_Def => Object_Definition (Parent (Prev)),
11965 Curr_Obj_Def => Obj_Def);
11967 Set_Full_View (Prev, Id);
11968 Set_Is_Public (Id, Is_Public (Prev));
11969 Set_Is_Internal (Id);
11970 Append_Entity (Id, Current_Scope);
11972 -- Check ALIASED present if present before (RM 7.4(7))
11974 if Is_Aliased (Prev)
11975 and then not Aliased_Present (N)
11977 Error_Msg_Sloc := Sloc (Prev);
11978 Error_Msg_N ("ALIASED required (see declaration #)", N);
11981 -- Check that placement is in private part and that the incomplete
11982 -- declaration appeared in the visible part.
11984 if Ekind (Current_Scope) = E_Package
11985 and then not In_Private_Part (Current_Scope)
11987 Error_Msg_Sloc := Sloc (Prev);
11989 ("full constant for declaration # must be in private part", N);
11991 elsif Ekind (Current_Scope) = E_Package
11993 List_Containing (Parent (Prev)) /=
11994 Visible_Declarations (Package_Specification (Current_Scope))
11997 ("deferred constant must be declared in visible part",
12001 if Is_Access_Type (T)
12002 and then Nkind (Expression (N)) = N_Allocator
12004 Check_Recursive_Declaration (Designated_Type (T));
12007 -- A deferred constant is a visible entity. If type has invariants,
12008 -- verify that the initial value satisfies them.
12010 if Has_Invariants (T) and then Present (Invariant_Procedure (T)) then
12012 Make_Invariant_Call (New_Occurrence_Of (Prev, Sloc (N))));
12015 end Constant_Redeclaration;
12017 ----------------------
12018 -- Constrain_Access --
12019 ----------------------
12021 procedure Constrain_Access
12022 (Def_Id : in out Entity_Id;
12024 Related_Nod : Node_Id)
12026 T : constant Entity_Id := Entity (Subtype_Mark (S));
12027 Desig_Type : constant Entity_Id := Designated_Type (T);
12028 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
12029 Constraint_OK : Boolean := True;
12032 if Is_Array_Type (Desig_Type) then
12033 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
12035 elsif (Is_Record_Type (Desig_Type)
12036 or else Is_Incomplete_Or_Private_Type (Desig_Type))
12037 and then not Is_Constrained (Desig_Type)
12039 -- ??? The following code is a temporary bypass to ignore a
12040 -- discriminant constraint on access type if it is constraining
12041 -- the current record. Avoid creating the implicit subtype of the
12042 -- record we are currently compiling since right now, we cannot
12043 -- handle these. For now, just return the access type itself.
12045 if Desig_Type = Current_Scope
12046 and then No (Def_Id)
12048 Set_Ekind (Desig_Subtype, E_Record_Subtype);
12049 Def_Id := Entity (Subtype_Mark (S));
12051 -- This call added to ensure that the constraint is analyzed
12052 -- (needed for a B test). Note that we still return early from
12053 -- this procedure to avoid recursive processing. ???
12055 Constrain_Discriminated_Type
12056 (Desig_Subtype, S, Related_Nod, For_Access => True);
12060 -- Enforce rule that the constraint is illegal if there is an
12061 -- unconstrained view of the designated type. This means that the
12062 -- partial view (either a private type declaration or a derivation
12063 -- from a private type) has no discriminants. (Defect Report
12064 -- 8652/0008, Technical Corrigendum 1, checked by ACATS B371001).
12066 -- Rule updated for Ada 2005: The private type is said to have
12067 -- a constrained partial view, given that objects of the type
12068 -- can be declared. Furthermore, the rule applies to all access
12069 -- types, unlike the rule concerning default discriminants (see
12072 if (Ekind (T) = E_General_Access_Type or else Ada_Version >= Ada_2005)
12073 and then Has_Private_Declaration (Desig_Type)
12074 and then In_Open_Scopes (Scope (Desig_Type))
12075 and then Has_Discriminants (Desig_Type)
12078 Pack : constant Node_Id :=
12079 Unit_Declaration_Node (Scope (Desig_Type));
12084 if Nkind (Pack) = N_Package_Declaration then
12085 Decls := Visible_Declarations (Specification (Pack));
12086 Decl := First (Decls);
12087 while Present (Decl) loop
12088 if (Nkind (Decl) = N_Private_Type_Declaration
12089 and then Chars (Defining_Identifier (Decl)) =
12090 Chars (Desig_Type))
12093 (Nkind (Decl) = N_Full_Type_Declaration
12095 Chars (Defining_Identifier (Decl)) =
12097 and then Is_Derived_Type (Desig_Type)
12099 Has_Private_Declaration (Etype (Desig_Type)))
12101 if No (Discriminant_Specifications (Decl)) then
12103 ("cannot constrain access type if designated "
12104 & "type has constrained partial view", S);
12116 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
12117 For_Access => True);
12119 elsif Is_Concurrent_Type (Desig_Type)
12120 and then not Is_Constrained (Desig_Type)
12122 Constrain_Concurrent (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
12125 Error_Msg_N ("invalid constraint on access type", S);
12127 -- We simply ignore an invalid constraint
12129 Desig_Subtype := Desig_Type;
12130 Constraint_OK := False;
12133 if No (Def_Id) then
12134 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
12136 Set_Ekind (Def_Id, E_Access_Subtype);
12139 if Constraint_OK then
12140 Set_Etype (Def_Id, Base_Type (T));
12142 if Is_Private_Type (Desig_Type) then
12143 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
12146 Set_Etype (Def_Id, Any_Type);
12149 Set_Size_Info (Def_Id, T);
12150 Set_Is_Constrained (Def_Id, Constraint_OK);
12151 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
12152 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12153 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
12155 Conditional_Delay (Def_Id, T);
12157 -- AI-363 : Subtypes of general access types whose designated types have
12158 -- default discriminants are disallowed. In instances, the rule has to
12159 -- be checked against the actual, of which T is the subtype. In a
12160 -- generic body, the rule is checked assuming that the actual type has
12161 -- defaulted discriminants.
12163 if Ada_Version >= Ada_2005 or else Warn_On_Ada_2005_Compatibility then
12164 if Ekind (Base_Type (T)) = E_General_Access_Type
12165 and then Has_Defaulted_Discriminants (Desig_Type)
12167 if Ada_Version < Ada_2005 then
12169 ("access subtype of general access type would not " &
12170 "be allowed in Ada 2005?y?", S);
12173 ("access subtype of general access type not allowed", S);
12176 Error_Msg_N ("\discriminants have defaults", S);
12178 elsif Is_Access_Type (T)
12179 and then Is_Generic_Type (Desig_Type)
12180 and then Has_Discriminants (Desig_Type)
12181 and then In_Package_Body (Current_Scope)
12183 if Ada_Version < Ada_2005 then
12185 ("access subtype would not be allowed in generic body "
12186 & "in Ada 2005?y?", S);
12189 ("access subtype not allowed in generic body", S);
12193 ("\designated type is a discriminated formal", S);
12196 end Constrain_Access;
12198 ---------------------
12199 -- Constrain_Array --
12200 ---------------------
12202 procedure Constrain_Array
12203 (Def_Id : in out Entity_Id;
12205 Related_Nod : Node_Id;
12206 Related_Id : Entity_Id;
12207 Suffix : Character)
12209 C : constant Node_Id := Constraint (SI);
12210 Number_Of_Constraints : Nat := 0;
12213 Constraint_OK : Boolean := True;
12216 T := Entity (Subtype_Mark (SI));
12218 if Is_Access_Type (T) then
12219 T := Designated_Type (T);
12222 -- If an index constraint follows a subtype mark in a subtype indication
12223 -- then the type or subtype denoted by the subtype mark must not already
12224 -- impose an index constraint. The subtype mark must denote either an
12225 -- unconstrained array type or an access type whose designated type
12226 -- is such an array type... (RM 3.6.1)
12228 if Is_Constrained (T) then
12229 Error_Msg_N ("array type is already constrained", Subtype_Mark (SI));
12230 Constraint_OK := False;
12233 S := First (Constraints (C));
12234 while Present (S) loop
12235 Number_Of_Constraints := Number_Of_Constraints + 1;
12239 -- In either case, the index constraint must provide a discrete
12240 -- range for each index of the array type and the type of each
12241 -- discrete range must be the same as that of the corresponding
12242 -- index. (RM 3.6.1)
12244 if Number_Of_Constraints /= Number_Dimensions (T) then
12245 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
12246 Constraint_OK := False;
12249 S := First (Constraints (C));
12250 Index := First_Index (T);
12253 -- Apply constraints to each index type
12255 for J in 1 .. Number_Of_Constraints loop
12256 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
12264 if No (Def_Id) then
12266 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
12267 Set_Parent (Def_Id, Related_Nod);
12270 Set_Ekind (Def_Id, E_Array_Subtype);
12273 Set_Size_Info (Def_Id, (T));
12274 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12275 Set_Etype (Def_Id, Base_Type (T));
12277 if Constraint_OK then
12278 Set_First_Index (Def_Id, First (Constraints (C)));
12280 Set_First_Index (Def_Id, First_Index (T));
12283 Set_Is_Constrained (Def_Id, True);
12284 Set_Is_Aliased (Def_Id, Is_Aliased (T));
12285 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12287 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
12288 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
12290 -- A subtype does not inherit the Packed_Array_Impl_Type of is parent.
12291 -- We need to initialize the attribute because if Def_Id is previously
12292 -- analyzed through a limited_with clause, it will have the attributes
12293 -- of an incomplete type, one of which is an Elist that overlaps the
12294 -- Packed_Array_Impl_Type field.
12296 Set_Packed_Array_Impl_Type (Def_Id, Empty);
12298 -- Build a freeze node if parent still needs one. Also make sure that
12299 -- the Depends_On_Private status is set because the subtype will need
12300 -- reprocessing at the time the base type does, and also we must set a
12301 -- conditional delay.
12303 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
12304 Conditional_Delay (Def_Id, T);
12305 end Constrain_Array;
12307 ------------------------------
12308 -- Constrain_Component_Type --
12309 ------------------------------
12311 function Constrain_Component_Type
12313 Constrained_Typ : Entity_Id;
12314 Related_Node : Node_Id;
12316 Constraints : Elist_Id) return Entity_Id
12318 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
12319 Compon_Type : constant Entity_Id := Etype (Comp);
12321 function Build_Constrained_Array_Type
12322 (Old_Type : Entity_Id) return Entity_Id;
12323 -- If Old_Type is an array type, one of whose indexes is constrained
12324 -- by a discriminant, build an Itype whose constraint replaces the
12325 -- discriminant with its value in the constraint.
12327 function Build_Constrained_Discriminated_Type
12328 (Old_Type : Entity_Id) return Entity_Id;
12329 -- Ditto for record components
12331 function Build_Constrained_Access_Type
12332 (Old_Type : Entity_Id) return Entity_Id;
12333 -- Ditto for access types. Makes use of previous two functions, to
12334 -- constrain designated type.
12336 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
12337 -- T is an array or discriminated type, C is a list of constraints
12338 -- that apply to T. This routine builds the constrained subtype.
12340 function Is_Discriminant (Expr : Node_Id) return Boolean;
12341 -- Returns True if Expr is a discriminant
12343 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
12344 -- Find the value of discriminant Discrim in Constraint
12346 -----------------------------------
12347 -- Build_Constrained_Access_Type --
12348 -----------------------------------
12350 function Build_Constrained_Access_Type
12351 (Old_Type : Entity_Id) return Entity_Id
12353 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
12355 Desig_Subtype : Entity_Id;
12359 -- if the original access type was not embedded in the enclosing
12360 -- type definition, there is no need to produce a new access
12361 -- subtype. In fact every access type with an explicit constraint
12362 -- generates an itype whose scope is the enclosing record.
12364 if not Is_Type (Scope (Old_Type)) then
12367 elsif Is_Array_Type (Desig_Type) then
12368 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
12370 elsif Has_Discriminants (Desig_Type) then
12372 -- This may be an access type to an enclosing record type for
12373 -- which we are constructing the constrained components. Return
12374 -- the enclosing record subtype. This is not always correct,
12375 -- but avoids infinite recursion. ???
12377 Desig_Subtype := Any_Type;
12379 for J in reverse 0 .. Scope_Stack.Last loop
12380 Scop := Scope_Stack.Table (J).Entity;
12383 and then Base_Type (Scop) = Base_Type (Desig_Type)
12385 Desig_Subtype := Scop;
12388 exit when not Is_Type (Scop);
12391 if Desig_Subtype = Any_Type then
12393 Build_Constrained_Discriminated_Type (Desig_Type);
12400 if Desig_Subtype /= Desig_Type then
12402 -- The Related_Node better be here or else we won't be able
12403 -- to attach new itypes to a node in the tree.
12405 pragma Assert (Present (Related_Node));
12407 Itype := Create_Itype (E_Access_Subtype, Related_Node);
12409 Set_Etype (Itype, Base_Type (Old_Type));
12410 Set_Size_Info (Itype, (Old_Type));
12411 Set_Directly_Designated_Type (Itype, Desig_Subtype);
12412 Set_Depends_On_Private (Itype, Has_Private_Component
12414 Set_Is_Access_Constant (Itype, Is_Access_Constant
12417 -- The new itype needs freezing when it depends on a not frozen
12418 -- type and the enclosing subtype needs freezing.
12420 if Has_Delayed_Freeze (Constrained_Typ)
12421 and then not Is_Frozen (Constrained_Typ)
12423 Conditional_Delay (Itype, Base_Type (Old_Type));
12431 end Build_Constrained_Access_Type;
12433 ----------------------------------
12434 -- Build_Constrained_Array_Type --
12435 ----------------------------------
12437 function Build_Constrained_Array_Type
12438 (Old_Type : Entity_Id) return Entity_Id
12442 Old_Index : Node_Id;
12443 Range_Node : Node_Id;
12444 Constr_List : List_Id;
12446 Need_To_Create_Itype : Boolean := False;
12449 Old_Index := First_Index (Old_Type);
12450 while Present (Old_Index) loop
12451 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
12453 if Is_Discriminant (Lo_Expr)
12455 Is_Discriminant (Hi_Expr)
12457 Need_To_Create_Itype := True;
12460 Next_Index (Old_Index);
12463 if Need_To_Create_Itype then
12464 Constr_List := New_List;
12466 Old_Index := First_Index (Old_Type);
12467 while Present (Old_Index) loop
12468 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
12470 if Is_Discriminant (Lo_Expr) then
12471 Lo_Expr := Get_Discr_Value (Lo_Expr);
12474 if Is_Discriminant (Hi_Expr) then
12475 Hi_Expr := Get_Discr_Value (Hi_Expr);
12480 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
12482 Append (Range_Node, To => Constr_List);
12484 Next_Index (Old_Index);
12487 return Build_Subtype (Old_Type, Constr_List);
12492 end Build_Constrained_Array_Type;
12494 ------------------------------------------
12495 -- Build_Constrained_Discriminated_Type --
12496 ------------------------------------------
12498 function Build_Constrained_Discriminated_Type
12499 (Old_Type : Entity_Id) return Entity_Id
12502 Constr_List : List_Id;
12503 Old_Constraint : Elmt_Id;
12505 Need_To_Create_Itype : Boolean := False;
12508 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
12509 while Present (Old_Constraint) loop
12510 Expr := Node (Old_Constraint);
12512 if Is_Discriminant (Expr) then
12513 Need_To_Create_Itype := True;
12516 Next_Elmt (Old_Constraint);
12519 if Need_To_Create_Itype then
12520 Constr_List := New_List;
12522 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
12523 while Present (Old_Constraint) loop
12524 Expr := Node (Old_Constraint);
12526 if Is_Discriminant (Expr) then
12527 Expr := Get_Discr_Value (Expr);
12530 Append (New_Copy_Tree (Expr), To => Constr_List);
12532 Next_Elmt (Old_Constraint);
12535 return Build_Subtype (Old_Type, Constr_List);
12540 end Build_Constrained_Discriminated_Type;
12542 -------------------
12543 -- Build_Subtype --
12544 -------------------
12546 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
12548 Subtyp_Decl : Node_Id;
12549 Def_Id : Entity_Id;
12550 Btyp : Entity_Id := Base_Type (T);
12553 -- The Related_Node better be here or else we won't be able to
12554 -- attach new itypes to a node in the tree.
12556 pragma Assert (Present (Related_Node));
12558 -- If the view of the component's type is incomplete or private
12559 -- with unknown discriminants, then the constraint must be applied
12560 -- to the full type.
12562 if Has_Unknown_Discriminants (Btyp)
12563 and then Present (Underlying_Type (Btyp))
12565 Btyp := Underlying_Type (Btyp);
12569 Make_Subtype_Indication (Loc,
12570 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
12571 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
12573 Def_Id := Create_Itype (Ekind (T), Related_Node);
12576 Make_Subtype_Declaration (Loc,
12577 Defining_Identifier => Def_Id,
12578 Subtype_Indication => Indic);
12580 Set_Parent (Subtyp_Decl, Parent (Related_Node));
12582 -- Itypes must be analyzed with checks off (see package Itypes)
12584 Analyze (Subtyp_Decl, Suppress => All_Checks);
12589 ---------------------
12590 -- Get_Discr_Value --
12591 ---------------------
12593 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
12598 -- The discriminant may be declared for the type, in which case we
12599 -- find it by iterating over the list of discriminants. If the
12600 -- discriminant is inherited from a parent type, it appears as the
12601 -- corresponding discriminant of the current type. This will be the
12602 -- case when constraining an inherited component whose constraint is
12603 -- given by a discriminant of the parent.
12605 D := First_Discriminant (Typ);
12606 E := First_Elmt (Constraints);
12608 while Present (D) loop
12609 if D = Entity (Discrim)
12610 or else D = CR_Discriminant (Entity (Discrim))
12611 or else Corresponding_Discriminant (D) = Entity (Discrim)
12616 Next_Discriminant (D);
12620 -- The Corresponding_Discriminant mechanism is incomplete, because
12621 -- the correspondence between new and old discriminants is not one
12622 -- to one: one new discriminant can constrain several old ones. In
12623 -- that case, scan sequentially the stored_constraint, the list of
12624 -- discriminants of the parents, and the constraints.
12626 -- Previous code checked for the present of the Stored_Constraint
12627 -- list for the derived type, but did not use it at all. Should it
12628 -- be present when the component is a discriminated task type?
12630 if Is_Derived_Type (Typ)
12631 and then Scope (Entity (Discrim)) = Etype (Typ)
12633 D := First_Discriminant (Etype (Typ));
12634 E := First_Elmt (Constraints);
12635 while Present (D) loop
12636 if D = Entity (Discrim) then
12640 Next_Discriminant (D);
12645 -- Something is wrong if we did not find the value
12647 raise Program_Error;
12648 end Get_Discr_Value;
12650 ---------------------
12651 -- Is_Discriminant --
12652 ---------------------
12654 function Is_Discriminant (Expr : Node_Id) return Boolean is
12655 Discrim_Scope : Entity_Id;
12658 if Denotes_Discriminant (Expr) then
12659 Discrim_Scope := Scope (Entity (Expr));
12661 -- Either we have a reference to one of Typ's discriminants,
12663 pragma Assert (Discrim_Scope = Typ
12665 -- or to the discriminants of the parent type, in the case
12666 -- of a derivation of a tagged type with variants.
12668 or else Discrim_Scope = Etype (Typ)
12669 or else Full_View (Discrim_Scope) = Etype (Typ)
12671 -- or same as above for the case where the discriminants
12672 -- were declared in Typ's private view.
12674 or else (Is_Private_Type (Discrim_Scope)
12675 and then Chars (Discrim_Scope) = Chars (Typ))
12677 -- or else we are deriving from the full view and the
12678 -- discriminant is declared in the private entity.
12680 or else (Is_Private_Type (Typ)
12681 and then Chars (Discrim_Scope) = Chars (Typ))
12683 -- Or we are constrained the corresponding record of a
12684 -- synchronized type that completes a private declaration.
12686 or else (Is_Concurrent_Record_Type (Typ)
12688 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
12690 -- or we have a class-wide type, in which case make sure the
12691 -- discriminant found belongs to the root type.
12693 or else (Is_Class_Wide_Type (Typ)
12694 and then Etype (Typ) = Discrim_Scope));
12699 -- In all other cases we have something wrong
12702 end Is_Discriminant;
12704 -- Start of processing for Constrain_Component_Type
12707 if Nkind (Parent (Comp)) = N_Component_Declaration
12708 and then Comes_From_Source (Parent (Comp))
12709 and then Comes_From_Source
12710 (Subtype_Indication (Component_Definition (Parent (Comp))))
12713 (Subtype_Indication (Component_Definition (Parent (Comp))))
12715 return Compon_Type;
12717 elsif Is_Array_Type (Compon_Type) then
12718 return Build_Constrained_Array_Type (Compon_Type);
12720 elsif Has_Discriminants (Compon_Type) then
12721 return Build_Constrained_Discriminated_Type (Compon_Type);
12723 elsif Is_Access_Type (Compon_Type) then
12724 return Build_Constrained_Access_Type (Compon_Type);
12727 return Compon_Type;
12729 end Constrain_Component_Type;
12731 --------------------------
12732 -- Constrain_Concurrent --
12733 --------------------------
12735 -- For concurrent types, the associated record value type carries the same
12736 -- discriminants, so when we constrain a concurrent type, we must constrain
12737 -- the corresponding record type as well.
12739 procedure Constrain_Concurrent
12740 (Def_Id : in out Entity_Id;
12742 Related_Nod : Node_Id;
12743 Related_Id : Entity_Id;
12744 Suffix : Character)
12746 -- Retrieve Base_Type to ensure getting to the concurrent type in the
12747 -- case of a private subtype (needed when only doing semantic analysis).
12749 T_Ent : Entity_Id := Base_Type (Entity (Subtype_Mark (SI)));
12753 if Is_Access_Type (T_Ent) then
12754 T_Ent := Designated_Type (T_Ent);
12757 T_Val := Corresponding_Record_Type (T_Ent);
12759 if Present (T_Val) then
12761 if No (Def_Id) then
12762 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
12765 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
12767 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12768 Set_Corresponding_Record_Type (Def_Id,
12769 Constrain_Corresponding_Record (Def_Id, T_Val, Related_Nod));
12772 -- If there is no associated record, expansion is disabled and this
12773 -- is a generic context. Create a subtype in any case, so that
12774 -- semantic analysis can proceed.
12776 if No (Def_Id) then
12777 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
12780 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
12782 end Constrain_Concurrent;
12784 ------------------------------------
12785 -- Constrain_Corresponding_Record --
12786 ------------------------------------
12788 function Constrain_Corresponding_Record
12789 (Prot_Subt : Entity_Id;
12790 Corr_Rec : Entity_Id;
12791 Related_Nod : Node_Id) return Entity_Id
12793 T_Sub : constant Entity_Id :=
12794 Create_Itype (E_Record_Subtype, Related_Nod, Corr_Rec, 'C');
12797 Set_Etype (T_Sub, Corr_Rec);
12798 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
12799 Set_Is_Constrained (T_Sub, True);
12800 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
12801 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
12803 if Has_Discriminants (Prot_Subt) then -- False only if errors.
12804 Set_Discriminant_Constraint
12805 (T_Sub, Discriminant_Constraint (Prot_Subt));
12806 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
12807 Create_Constrained_Components
12808 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
12811 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
12813 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
12814 Conditional_Delay (T_Sub, Corr_Rec);
12817 -- This is a component subtype: it will be frozen in the context of
12818 -- the enclosing record's init_proc, so that discriminant references
12819 -- are resolved to discriminals. (Note: we used to skip freezing
12820 -- altogether in that case, which caused errors downstream for
12821 -- components of a bit packed array type).
12823 Set_Has_Delayed_Freeze (T_Sub);
12827 end Constrain_Corresponding_Record;
12829 -----------------------
12830 -- Constrain_Decimal --
12831 -----------------------
12833 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
12834 T : constant Entity_Id := Entity (Subtype_Mark (S));
12835 C : constant Node_Id := Constraint (S);
12836 Loc : constant Source_Ptr := Sloc (C);
12837 Range_Expr : Node_Id;
12838 Digits_Expr : Node_Id;
12843 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
12845 if Nkind (C) = N_Range_Constraint then
12846 Range_Expr := Range_Expression (C);
12847 Digits_Val := Digits_Value (T);
12850 pragma Assert (Nkind (C) = N_Digits_Constraint);
12852 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
12854 Digits_Expr := Digits_Expression (C);
12855 Analyze_And_Resolve (Digits_Expr, Any_Integer);
12857 Check_Digits_Expression (Digits_Expr);
12858 Digits_Val := Expr_Value (Digits_Expr);
12860 if Digits_Val > Digits_Value (T) then
12862 ("digits expression is incompatible with subtype", C);
12863 Digits_Val := Digits_Value (T);
12866 if Present (Range_Constraint (C)) then
12867 Range_Expr := Range_Expression (Range_Constraint (C));
12869 Range_Expr := Empty;
12873 Set_Etype (Def_Id, Base_Type (T));
12874 Set_Size_Info (Def_Id, (T));
12875 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12876 Set_Delta_Value (Def_Id, Delta_Value (T));
12877 Set_Scale_Value (Def_Id, Scale_Value (T));
12878 Set_Small_Value (Def_Id, Small_Value (T));
12879 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
12880 Set_Digits_Value (Def_Id, Digits_Val);
12882 -- Manufacture range from given digits value if no range present
12884 if No (Range_Expr) then
12885 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
12889 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
12891 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
12894 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
12895 Set_Discrete_RM_Size (Def_Id);
12897 -- Unconditionally delay the freeze, since we cannot set size
12898 -- information in all cases correctly until the freeze point.
12900 Set_Has_Delayed_Freeze (Def_Id);
12901 end Constrain_Decimal;
12903 ----------------------------------
12904 -- Constrain_Discriminated_Type --
12905 ----------------------------------
12907 procedure Constrain_Discriminated_Type
12908 (Def_Id : Entity_Id;
12910 Related_Nod : Node_Id;
12911 For_Access : Boolean := False)
12913 E : constant Entity_Id := Entity (Subtype_Mark (S));
12916 Elist : Elist_Id := New_Elmt_List;
12918 procedure Fixup_Bad_Constraint;
12919 -- This is called after finding a bad constraint, and after having
12920 -- posted an appropriate error message. The mission is to leave the
12921 -- entity T in as reasonable state as possible.
12923 --------------------------
12924 -- Fixup_Bad_Constraint --
12925 --------------------------
12927 procedure Fixup_Bad_Constraint is
12929 -- Set a reasonable Ekind for the entity. For an incomplete type,
12930 -- we can't do much, but for other types, we can set the proper
12931 -- corresponding subtype kind.
12933 if Ekind (T) = E_Incomplete_Type then
12934 Set_Ekind (Def_Id, Ekind (T));
12936 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
12939 -- Set Etype to the known type, to reduce chances of cascaded errors
12941 Set_Etype (Def_Id, E);
12942 Set_Error_Posted (Def_Id);
12943 end Fixup_Bad_Constraint;
12945 -- Start of processing for Constrain_Discriminated_Type
12948 C := Constraint (S);
12950 -- A discriminant constraint is only allowed in a subtype indication,
12951 -- after a subtype mark. This subtype mark must denote either a type
12952 -- with discriminants, or an access type whose designated type is a
12953 -- type with discriminants. A discriminant constraint specifies the
12954 -- values of these discriminants (RM 3.7.2(5)).
12956 T := Base_Type (Entity (Subtype_Mark (S)));
12958 if Is_Access_Type (T) then
12959 T := Designated_Type (T);
12962 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal.
12963 -- Avoid generating an error for access-to-incomplete subtypes.
12965 if Ada_Version >= Ada_2005
12966 and then Ekind (T) = E_Incomplete_Type
12967 and then Nkind (Parent (S)) = N_Subtype_Declaration
12968 and then not Is_Itype (Def_Id)
12970 -- A little sanity check, emit an error message if the type
12971 -- has discriminants to begin with. Type T may be a regular
12972 -- incomplete type or imported via a limited with clause.
12974 if Has_Discriminants (T)
12975 or else (From_Limited_With (T)
12976 and then Present (Non_Limited_View (T))
12977 and then Nkind (Parent (Non_Limited_View (T))) =
12978 N_Full_Type_Declaration
12979 and then Present (Discriminant_Specifications
12980 (Parent (Non_Limited_View (T)))))
12983 ("(Ada 2005) incomplete subtype may not be constrained", C);
12985 Error_Msg_N ("invalid constraint: type has no discriminant", C);
12988 Fixup_Bad_Constraint;
12991 -- Check that the type has visible discriminants. The type may be
12992 -- a private type with unknown discriminants whose full view has
12993 -- discriminants which are invisible.
12995 elsif not Has_Discriminants (T)
12997 (Has_Unknown_Discriminants (T)
12998 and then Is_Private_Type (T))
13000 Error_Msg_N ("invalid constraint: type has no discriminant", C);
13001 Fixup_Bad_Constraint;
13004 elsif Is_Constrained (E)
13005 or else (Ekind (E) = E_Class_Wide_Subtype
13006 and then Present (Discriminant_Constraint (E)))
13008 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
13009 Fixup_Bad_Constraint;
13013 -- T may be an unconstrained subtype (e.g. a generic actual).
13014 -- Constraint applies to the base type.
13016 T := Base_Type (T);
13018 Elist := Build_Discriminant_Constraints (T, S);
13020 -- If the list returned was empty we had an error in building the
13021 -- discriminant constraint. We have also already signalled an error
13022 -- in the incomplete type case
13024 if Is_Empty_Elmt_List (Elist) then
13025 Fixup_Bad_Constraint;
13029 Build_Discriminated_Subtype (T, Def_Id, Elist, Related_Nod, For_Access);
13030 end Constrain_Discriminated_Type;
13032 ---------------------------
13033 -- Constrain_Enumeration --
13034 ---------------------------
13036 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
13037 T : constant Entity_Id := Entity (Subtype_Mark (S));
13038 C : constant Node_Id := Constraint (S);
13041 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13043 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
13045 Set_Etype (Def_Id, Base_Type (T));
13046 Set_Size_Info (Def_Id, (T));
13047 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13048 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13050 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13052 Set_Discrete_RM_Size (Def_Id);
13053 end Constrain_Enumeration;
13055 ----------------------
13056 -- Constrain_Float --
13057 ----------------------
13059 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
13060 T : constant Entity_Id := Entity (Subtype_Mark (S));
13066 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
13068 Set_Etype (Def_Id, Base_Type (T));
13069 Set_Size_Info (Def_Id, (T));
13070 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13072 -- Process the constraint
13074 C := Constraint (S);
13076 -- Digits constraint present
13078 if Nkind (C) = N_Digits_Constraint then
13080 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
13081 Check_Restriction (No_Obsolescent_Features, C);
13083 if Warn_On_Obsolescent_Feature then
13085 ("subtype digits constraint is an " &
13086 "obsolescent feature (RM J.3(8))?j?", C);
13089 D := Digits_Expression (C);
13090 Analyze_And_Resolve (D, Any_Integer);
13091 Check_Digits_Expression (D);
13092 Set_Digits_Value (Def_Id, Expr_Value (D));
13094 -- Check that digits value is in range. Obviously we can do this
13095 -- at compile time, but it is strictly a runtime check, and of
13096 -- course there is an ACVC test that checks this.
13098 if Digits_Value (Def_Id) > Digits_Value (T) then
13099 Error_Msg_Uint_1 := Digits_Value (T);
13100 Error_Msg_N ("??digits value is too large, maximum is ^", D);
13102 Make_Raise_Constraint_Error (Sloc (D),
13103 Reason => CE_Range_Check_Failed);
13104 Insert_Action (Declaration_Node (Def_Id), Rais);
13107 C := Range_Constraint (C);
13109 -- No digits constraint present
13112 Set_Digits_Value (Def_Id, Digits_Value (T));
13115 -- Range constraint present
13117 if Nkind (C) = N_Range_Constraint then
13118 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13120 -- No range constraint present
13123 pragma Assert (No (C));
13124 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13127 Set_Is_Constrained (Def_Id);
13128 end Constrain_Float;
13130 ---------------------
13131 -- Constrain_Index --
13132 ---------------------
13134 procedure Constrain_Index
13137 Related_Nod : Node_Id;
13138 Related_Id : Entity_Id;
13139 Suffix : Character;
13140 Suffix_Index : Nat)
13142 Def_Id : Entity_Id;
13143 R : Node_Id := Empty;
13144 T : constant Entity_Id := Etype (Index);
13147 if Nkind (S) = N_Range
13149 (Nkind (S) = N_Attribute_Reference
13150 and then Attribute_Name (S) = Name_Range)
13152 -- A Range attribute will be transformed into N_Range by Resolve
13158 Process_Range_Expr_In_Decl (R, T);
13160 if not Error_Posted (S)
13162 (Nkind (S) /= N_Range
13163 or else not Covers (T, (Etype (Low_Bound (S))))
13164 or else not Covers (T, (Etype (High_Bound (S)))))
13166 if Base_Type (T) /= Any_Type
13167 and then Etype (Low_Bound (S)) /= Any_Type
13168 and then Etype (High_Bound (S)) /= Any_Type
13170 Error_Msg_N ("range expected", S);
13174 elsif Nkind (S) = N_Subtype_Indication then
13176 -- The parser has verified that this is a discrete indication
13178 Resolve_Discrete_Subtype_Indication (S, T);
13179 Bad_Predicated_Subtype_Use
13180 ("subtype& has predicate, not allowed in index constraint",
13181 S, Entity (Subtype_Mark (S)));
13183 R := Range_Expression (Constraint (S));
13185 -- Capture values of bounds and generate temporaries for them if
13186 -- needed, since checks may cause duplication of the expressions
13187 -- which must not be reevaluated.
13189 -- The forced evaluation removes side effects from expressions, which
13190 -- should occur also in GNATprove mode. Otherwise, we end up with
13191 -- unexpected insertions of actions at places where this is not
13192 -- supposed to occur, e.g. on default parameters of a call.
13194 if Expander_Active or GNATprove_Mode then
13195 Force_Evaluation (Low_Bound (R));
13196 Force_Evaluation (High_Bound (R));
13199 elsif Nkind (S) = N_Discriminant_Association then
13201 -- Syntactically valid in subtype indication
13203 Error_Msg_N ("invalid index constraint", S);
13204 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13207 -- Subtype_Mark case, no anonymous subtypes to construct
13212 if Is_Entity_Name (S) then
13213 if not Is_Type (Entity (S)) then
13214 Error_Msg_N ("expect subtype mark for index constraint", S);
13216 elsif Base_Type (Entity (S)) /= Base_Type (T) then
13217 Wrong_Type (S, Base_Type (T));
13219 -- Check error of subtype with predicate in index constraint
13222 Bad_Predicated_Subtype_Use
13223 ("subtype& has predicate, not allowed in index constraint",
13230 Error_Msg_N ("invalid index constraint", S);
13231 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13237 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
13239 Set_Etype (Def_Id, Base_Type (T));
13241 if Is_Modular_Integer_Type (T) then
13242 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13244 elsif Is_Integer_Type (T) then
13245 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13248 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13249 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13250 Set_First_Literal (Def_Id, First_Literal (T));
13253 Set_Size_Info (Def_Id, (T));
13254 Set_RM_Size (Def_Id, RM_Size (T));
13255 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13257 Set_Scalar_Range (Def_Id, R);
13259 Set_Etype (S, Def_Id);
13260 Set_Discrete_RM_Size (Def_Id);
13261 end Constrain_Index;
13263 -----------------------
13264 -- Constrain_Integer --
13265 -----------------------
13267 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
13268 T : constant Entity_Id := Entity (Subtype_Mark (S));
13269 C : constant Node_Id := Constraint (S);
13272 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13274 if Is_Modular_Integer_Type (T) then
13275 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13277 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13280 Set_Etype (Def_Id, Base_Type (T));
13281 Set_Size_Info (Def_Id, (T));
13282 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13283 Set_Discrete_RM_Size (Def_Id);
13284 end Constrain_Integer;
13286 ------------------------------
13287 -- Constrain_Ordinary_Fixed --
13288 ------------------------------
13290 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
13291 T : constant Entity_Id := Entity (Subtype_Mark (S));
13297 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
13298 Set_Etype (Def_Id, Base_Type (T));
13299 Set_Size_Info (Def_Id, (T));
13300 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13301 Set_Small_Value (Def_Id, Small_Value (T));
13303 -- Process the constraint
13305 C := Constraint (S);
13307 -- Delta constraint present
13309 if Nkind (C) = N_Delta_Constraint then
13311 Check_SPARK_05_Restriction ("delta constraint is not allowed", S);
13312 Check_Restriction (No_Obsolescent_Features, C);
13314 if Warn_On_Obsolescent_Feature then
13316 ("subtype delta constraint is an " &
13317 "obsolescent feature (RM J.3(7))?j?");
13320 D := Delta_Expression (C);
13321 Analyze_And_Resolve (D, Any_Real);
13322 Check_Delta_Expression (D);
13323 Set_Delta_Value (Def_Id, Expr_Value_R (D));
13325 -- Check that delta value is in range. Obviously we can do this
13326 -- at compile time, but it is strictly a runtime check, and of
13327 -- course there is an ACVC test that checks this.
13329 if Delta_Value (Def_Id) < Delta_Value (T) then
13330 Error_Msg_N ("??delta value is too small", D);
13332 Make_Raise_Constraint_Error (Sloc (D),
13333 Reason => CE_Range_Check_Failed);
13334 Insert_Action (Declaration_Node (Def_Id), Rais);
13337 C := Range_Constraint (C);
13339 -- No delta constraint present
13342 Set_Delta_Value (Def_Id, Delta_Value (T));
13345 -- Range constraint present
13347 if Nkind (C) = N_Range_Constraint then
13348 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13350 -- No range constraint present
13353 pragma Assert (No (C));
13354 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13358 Set_Discrete_RM_Size (Def_Id);
13360 -- Unconditionally delay the freeze, since we cannot set size
13361 -- information in all cases correctly until the freeze point.
13363 Set_Has_Delayed_Freeze (Def_Id);
13364 end Constrain_Ordinary_Fixed;
13366 -----------------------
13367 -- Contain_Interface --
13368 -----------------------
13370 function Contain_Interface
13371 (Iface : Entity_Id;
13372 Ifaces : Elist_Id) return Boolean
13374 Iface_Elmt : Elmt_Id;
13377 if Present (Ifaces) then
13378 Iface_Elmt := First_Elmt (Ifaces);
13379 while Present (Iface_Elmt) loop
13380 if Node (Iface_Elmt) = Iface then
13384 Next_Elmt (Iface_Elmt);
13389 end Contain_Interface;
13391 ---------------------------
13392 -- Convert_Scalar_Bounds --
13393 ---------------------------
13395 procedure Convert_Scalar_Bounds
13397 Parent_Type : Entity_Id;
13398 Derived_Type : Entity_Id;
13401 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
13408 -- Defend against previous errors
13410 if No (Scalar_Range (Derived_Type)) then
13411 Check_Error_Detected;
13415 Lo := Build_Scalar_Bound
13416 (Type_Low_Bound (Derived_Type),
13417 Parent_Type, Implicit_Base);
13419 Hi := Build_Scalar_Bound
13420 (Type_High_Bound (Derived_Type),
13421 Parent_Type, Implicit_Base);
13428 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
13430 Set_Parent (Rng, N);
13431 Set_Scalar_Range (Derived_Type, Rng);
13433 -- Analyze the bounds
13435 Analyze_And_Resolve (Lo, Implicit_Base);
13436 Analyze_And_Resolve (Hi, Implicit_Base);
13438 -- Analyze the range itself, except that we do not analyze it if
13439 -- the bounds are real literals, and we have a fixed-point type.
13440 -- The reason for this is that we delay setting the bounds in this
13441 -- case till we know the final Small and Size values (see circuit
13442 -- in Freeze.Freeze_Fixed_Point_Type for further details).
13444 if Is_Fixed_Point_Type (Parent_Type)
13445 and then Nkind (Lo) = N_Real_Literal
13446 and then Nkind (Hi) = N_Real_Literal
13450 -- Here we do the analysis of the range
13452 -- Note: we do this manually, since if we do a normal Analyze and
13453 -- Resolve call, there are problems with the conversions used for
13454 -- the derived type range.
13457 Set_Etype (Rng, Implicit_Base);
13458 Set_Analyzed (Rng, True);
13460 end Convert_Scalar_Bounds;
13462 -------------------
13463 -- Copy_And_Swap --
13464 -------------------
13466 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
13468 -- Initialize new full declaration entity by copying the pertinent
13469 -- fields of the corresponding private declaration entity.
13471 -- We temporarily set Ekind to a value appropriate for a type to
13472 -- avoid assert failures in Einfo from checking for setting type
13473 -- attributes on something that is not a type. Ekind (Priv) is an
13474 -- appropriate choice, since it allowed the attributes to be set
13475 -- in the first place. This Ekind value will be modified later.
13477 Set_Ekind (Full, Ekind (Priv));
13479 -- Also set Etype temporarily to Any_Type, again, in the absence
13480 -- of errors, it will be properly reset, and if there are errors,
13481 -- then we want a value of Any_Type to remain.
13483 Set_Etype (Full, Any_Type);
13485 -- Now start copying attributes
13487 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
13489 if Has_Discriminants (Full) then
13490 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
13491 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
13494 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
13495 Set_Homonym (Full, Homonym (Priv));
13496 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
13497 Set_Is_Public (Full, Is_Public (Priv));
13498 Set_Is_Pure (Full, Is_Pure (Priv));
13499 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
13500 Set_Has_Pragma_Unmodified (Full, Has_Pragma_Unmodified (Priv));
13501 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
13502 Set_Has_Pragma_Unreferenced_Objects
13503 (Full, Has_Pragma_Unreferenced_Objects
13506 Conditional_Delay (Full, Priv);
13508 if Is_Tagged_Type (Full) then
13509 Set_Direct_Primitive_Operations
13510 (Full, Direct_Primitive_Operations (Priv));
13511 Set_No_Tagged_Streams_Pragma
13512 (Full, No_Tagged_Streams_Pragma (Priv));
13514 if Is_Base_Type (Priv) then
13515 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
13519 Set_Is_Volatile (Full, Is_Volatile (Priv));
13520 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
13521 Set_Scope (Full, Scope (Priv));
13522 Set_Next_Entity (Full, Next_Entity (Priv));
13523 Set_First_Entity (Full, First_Entity (Priv));
13524 Set_Last_Entity (Full, Last_Entity (Priv));
13526 -- If access types have been recorded for later handling, keep them in
13527 -- the full view so that they get handled when the full view freeze
13528 -- node is expanded.
13530 if Present (Freeze_Node (Priv))
13531 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
13533 Ensure_Freeze_Node (Full);
13534 Set_Access_Types_To_Process
13535 (Freeze_Node (Full),
13536 Access_Types_To_Process (Freeze_Node (Priv)));
13539 -- Swap the two entities. Now Private is the full type entity and Full
13540 -- is the private one. They will be swapped back at the end of the
13541 -- private part. This swapping ensures that the entity that is visible
13542 -- in the private part is the full declaration.
13544 Exchange_Entities (Priv, Full);
13545 Append_Entity (Full, Scope (Full));
13548 -------------------------------------
13549 -- Copy_Array_Base_Type_Attributes --
13550 -------------------------------------
13552 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
13554 Set_Component_Alignment (T1, Component_Alignment (T2));
13555 Set_Component_Type (T1, Component_Type (T2));
13556 Set_Component_Size (T1, Component_Size (T2));
13557 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
13558 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
13559 Set_Has_Protected (T1, Has_Protected (T2));
13560 Set_Has_Task (T1, Has_Task (T2));
13561 Set_Is_Packed (T1, Is_Packed (T2));
13562 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
13563 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
13564 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
13565 end Copy_Array_Base_Type_Attributes;
13567 -----------------------------------
13568 -- Copy_Array_Subtype_Attributes --
13569 -----------------------------------
13571 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
13573 Set_Size_Info (T1, T2);
13575 Set_First_Index (T1, First_Index (T2));
13576 Set_Is_Aliased (T1, Is_Aliased (T2));
13577 Set_Is_Volatile (T1, Is_Volatile (T2));
13578 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
13579 Set_Is_Constrained (T1, Is_Constrained (T2));
13580 Set_Depends_On_Private (T1, Has_Private_Component (T2));
13581 Inherit_Rep_Item_Chain (T1, T2);
13582 Set_Convention (T1, Convention (T2));
13583 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
13584 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
13585 Set_Packed_Array_Impl_Type (T1, Packed_Array_Impl_Type (T2));
13586 end Copy_Array_Subtype_Attributes;
13588 -----------------------------------
13589 -- Create_Constrained_Components --
13590 -----------------------------------
13592 procedure Create_Constrained_Components
13594 Decl_Node : Node_Id;
13596 Constraints : Elist_Id)
13598 Loc : constant Source_Ptr := Sloc (Subt);
13599 Comp_List : constant Elist_Id := New_Elmt_List;
13600 Parent_Type : constant Entity_Id := Etype (Typ);
13601 Assoc_List : constant List_Id := New_List;
13602 Discr_Val : Elmt_Id;
13606 Is_Static : Boolean := True;
13608 procedure Collect_Fixed_Components (Typ : Entity_Id);
13609 -- Collect parent type components that do not appear in a variant part
13611 procedure Create_All_Components;
13612 -- Iterate over Comp_List to create the components of the subtype
13614 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
13615 -- Creates a new component from Old_Compon, copying all the fields from
13616 -- it, including its Etype, inserts the new component in the Subt entity
13617 -- chain and returns the new component.
13619 function Is_Variant_Record (T : Entity_Id) return Boolean;
13620 -- If true, and discriminants are static, collect only components from
13621 -- variants selected by discriminant values.
13623 ------------------------------
13624 -- Collect_Fixed_Components --
13625 ------------------------------
13627 procedure Collect_Fixed_Components (Typ : Entity_Id) is
13629 -- Build association list for discriminants, and find components of the
13630 -- variant part selected by the values of the discriminants.
13632 Old_C := First_Discriminant (Typ);
13633 Discr_Val := First_Elmt (Constraints);
13634 while Present (Old_C) loop
13635 Append_To (Assoc_List,
13636 Make_Component_Association (Loc,
13637 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
13638 Expression => New_Copy (Node (Discr_Val))));
13640 Next_Elmt (Discr_Val);
13641 Next_Discriminant (Old_C);
13644 -- The tag and the possible parent component are unconditionally in
13647 if Is_Tagged_Type (Typ) or else Has_Controlled_Component (Typ) then
13648 Old_C := First_Component (Typ);
13649 while Present (Old_C) loop
13650 if Nam_In (Chars (Old_C), Name_uTag, Name_uParent) then
13651 Append_Elmt (Old_C, Comp_List);
13654 Next_Component (Old_C);
13657 end Collect_Fixed_Components;
13659 ---------------------------
13660 -- Create_All_Components --
13661 ---------------------------
13663 procedure Create_All_Components is
13667 Comp := First_Elmt (Comp_List);
13668 while Present (Comp) loop
13669 Old_C := Node (Comp);
13670 New_C := Create_Component (Old_C);
13674 Constrain_Component_Type
13675 (Old_C, Subt, Decl_Node, Typ, Constraints));
13676 Set_Is_Public (New_C, Is_Public (Subt));
13680 end Create_All_Components;
13682 ----------------------
13683 -- Create_Component --
13684 ----------------------
13686 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
13687 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
13690 if Ekind (Old_Compon) = E_Discriminant
13691 and then Is_Completely_Hidden (Old_Compon)
13693 -- This is a shadow discriminant created for a discriminant of
13694 -- the parent type, which needs to be present in the subtype.
13695 -- Give the shadow discriminant an internal name that cannot
13696 -- conflict with that of visible components.
13698 Set_Chars (New_Compon, New_Internal_Name ('C'));
13701 -- Set the parent so we have a proper link for freezing etc. This is
13702 -- not a real parent pointer, since of course our parent does not own
13703 -- up to us and reference us, we are an illegitimate child of the
13704 -- original parent.
13706 Set_Parent (New_Compon, Parent (Old_Compon));
13708 -- If the old component's Esize was already determined and is a
13709 -- static value, then the new component simply inherits it. Otherwise
13710 -- the old component's size may require run-time determination, but
13711 -- the new component's size still might be statically determinable
13712 -- (if, for example it has a static constraint). In that case we want
13713 -- Layout_Type to recompute the component's size, so we reset its
13714 -- size and positional fields.
13716 if Frontend_Layout_On_Target
13717 and then not Known_Static_Esize (Old_Compon)
13719 Set_Esize (New_Compon, Uint_0);
13720 Init_Normalized_First_Bit (New_Compon);
13721 Init_Normalized_Position (New_Compon);
13722 Init_Normalized_Position_Max (New_Compon);
13725 -- We do not want this node marked as Comes_From_Source, since
13726 -- otherwise it would get first class status and a separate cross-
13727 -- reference line would be generated. Illegitimate children do not
13728 -- rate such recognition.
13730 Set_Comes_From_Source (New_Compon, False);
13732 -- But it is a real entity, and a birth certificate must be properly
13733 -- registered by entering it into the entity list.
13735 Enter_Name (New_Compon);
13738 end Create_Component;
13740 -----------------------
13741 -- Is_Variant_Record --
13742 -----------------------
13744 function Is_Variant_Record (T : Entity_Id) return Boolean is
13746 return Nkind (Parent (T)) = N_Full_Type_Declaration
13747 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
13748 and then Present (Component_List (Type_Definition (Parent (T))))
13751 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
13752 end Is_Variant_Record;
13754 -- Start of processing for Create_Constrained_Components
13757 pragma Assert (Subt /= Base_Type (Subt));
13758 pragma Assert (Typ = Base_Type (Typ));
13760 Set_First_Entity (Subt, Empty);
13761 Set_Last_Entity (Subt, Empty);
13763 -- Check whether constraint is fully static, in which case we can
13764 -- optimize the list of components.
13766 Discr_Val := First_Elmt (Constraints);
13767 while Present (Discr_Val) loop
13768 if not Is_OK_Static_Expression (Node (Discr_Val)) then
13769 Is_Static := False;
13773 Next_Elmt (Discr_Val);
13776 Set_Has_Static_Discriminants (Subt, Is_Static);
13780 -- Inherit the discriminants of the parent type
13782 Add_Discriminants : declare
13788 Old_C := First_Discriminant (Typ);
13790 while Present (Old_C) loop
13791 Num_Disc := Num_Disc + 1;
13792 New_C := Create_Component (Old_C);
13793 Set_Is_Public (New_C, Is_Public (Subt));
13794 Next_Discriminant (Old_C);
13797 -- For an untagged derived subtype, the number of discriminants may
13798 -- be smaller than the number of inherited discriminants, because
13799 -- several of them may be renamed by a single new discriminant or
13800 -- constrained. In this case, add the hidden discriminants back into
13801 -- the subtype, because they need to be present if the optimizer of
13802 -- the GCC 4.x back-end decides to break apart assignments between
13803 -- objects using the parent view into member-wise assignments.
13807 if Is_Derived_Type (Typ)
13808 and then not Is_Tagged_Type (Typ)
13810 Old_C := First_Stored_Discriminant (Typ);
13812 while Present (Old_C) loop
13813 Num_Gird := Num_Gird + 1;
13814 Next_Stored_Discriminant (Old_C);
13818 if Num_Gird > Num_Disc then
13820 -- Find out multiple uses of new discriminants, and add hidden
13821 -- components for the extra renamed discriminants. We recognize
13822 -- multiple uses through the Corresponding_Discriminant of a
13823 -- new discriminant: if it constrains several old discriminants,
13824 -- this field points to the last one in the parent type. The
13825 -- stored discriminants of the derived type have the same name
13826 -- as those of the parent.
13830 New_Discr : Entity_Id;
13831 Old_Discr : Entity_Id;
13834 Constr := First_Elmt (Stored_Constraint (Typ));
13835 Old_Discr := First_Stored_Discriminant (Typ);
13836 while Present (Constr) loop
13837 if Is_Entity_Name (Node (Constr))
13838 and then Ekind (Entity (Node (Constr))) = E_Discriminant
13840 New_Discr := Entity (Node (Constr));
13842 if Chars (Corresponding_Discriminant (New_Discr)) /=
13845 -- The new discriminant has been used to rename a
13846 -- subsequent old discriminant. Introduce a shadow
13847 -- component for the current old discriminant.
13849 New_C := Create_Component (Old_Discr);
13850 Set_Original_Record_Component (New_C, Old_Discr);
13854 -- The constraint has eliminated the old discriminant.
13855 -- Introduce a shadow component.
13857 New_C := Create_Component (Old_Discr);
13858 Set_Original_Record_Component (New_C, Old_Discr);
13861 Next_Elmt (Constr);
13862 Next_Stored_Discriminant (Old_Discr);
13866 end Add_Discriminants;
13869 and then Is_Variant_Record (Typ)
13871 Collect_Fixed_Components (Typ);
13873 Gather_Components (
13875 Component_List (Type_Definition (Parent (Typ))),
13876 Governed_By => Assoc_List,
13878 Report_Errors => Errors);
13879 pragma Assert (not Errors);
13881 Create_All_Components;
13883 -- If the subtype declaration is created for a tagged type derivation
13884 -- with constraints, we retrieve the record definition of the parent
13885 -- type to select the components of the proper variant.
13888 and then Is_Tagged_Type (Typ)
13889 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
13891 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
13892 and then Is_Variant_Record (Parent_Type)
13894 Collect_Fixed_Components (Typ);
13896 Gather_Components (
13898 Component_List (Type_Definition (Parent (Parent_Type))),
13899 Governed_By => Assoc_List,
13901 Report_Errors => Errors);
13902 pragma Assert (not Errors);
13904 -- If the tagged derivation has a type extension, collect all the
13905 -- new components therein.
13908 (Record_Extension_Part (Type_Definition (Parent (Typ))))
13910 Old_C := First_Component (Typ);
13911 while Present (Old_C) loop
13912 if Original_Record_Component (Old_C) = Old_C
13913 and then Chars (Old_C) /= Name_uTag
13914 and then Chars (Old_C) /= Name_uParent
13916 Append_Elmt (Old_C, Comp_List);
13919 Next_Component (Old_C);
13923 Create_All_Components;
13926 -- If discriminants are not static, or if this is a multi-level type
13927 -- extension, we have to include all components of the parent type.
13929 Old_C := First_Component (Typ);
13930 while Present (Old_C) loop
13931 New_C := Create_Component (Old_C);
13935 Constrain_Component_Type
13936 (Old_C, Subt, Decl_Node, Typ, Constraints));
13937 Set_Is_Public (New_C, Is_Public (Subt));
13939 Next_Component (Old_C);
13944 end Create_Constrained_Components;
13946 ------------------------------------------
13947 -- Decimal_Fixed_Point_Type_Declaration --
13948 ------------------------------------------
13950 procedure Decimal_Fixed_Point_Type_Declaration
13954 Loc : constant Source_Ptr := Sloc (Def);
13955 Digs_Expr : constant Node_Id := Digits_Expression (Def);
13956 Delta_Expr : constant Node_Id := Delta_Expression (Def);
13957 Implicit_Base : Entity_Id;
13964 Check_SPARK_05_Restriction
13965 ("decimal fixed point type is not allowed", Def);
13966 Check_Restriction (No_Fixed_Point, Def);
13968 -- Create implicit base type
13971 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
13972 Set_Etype (Implicit_Base, Implicit_Base);
13974 -- Analyze and process delta expression
13976 Analyze_And_Resolve (Delta_Expr, Universal_Real);
13978 Check_Delta_Expression (Delta_Expr);
13979 Delta_Val := Expr_Value_R (Delta_Expr);
13981 -- Check delta is power of 10, and determine scale value from it
13987 Scale_Val := Uint_0;
13990 if Val < Ureal_1 then
13991 while Val < Ureal_1 loop
13992 Val := Val * Ureal_10;
13993 Scale_Val := Scale_Val + 1;
13996 if Scale_Val > 18 then
13997 Error_Msg_N ("scale exceeds maximum value of 18", Def);
13998 Scale_Val := UI_From_Int (+18);
14002 while Val > Ureal_1 loop
14003 Val := Val / Ureal_10;
14004 Scale_Val := Scale_Val - 1;
14007 if Scale_Val < -18 then
14008 Error_Msg_N ("scale is less than minimum value of -18", Def);
14009 Scale_Val := UI_From_Int (-18);
14013 if Val /= Ureal_1 then
14014 Error_Msg_N ("delta expression must be a power of 10", Def);
14015 Delta_Val := Ureal_10 ** (-Scale_Val);
14019 -- Set delta, scale and small (small = delta for decimal type)
14021 Set_Delta_Value (Implicit_Base, Delta_Val);
14022 Set_Scale_Value (Implicit_Base, Scale_Val);
14023 Set_Small_Value (Implicit_Base, Delta_Val);
14025 -- Analyze and process digits expression
14027 Analyze_And_Resolve (Digs_Expr, Any_Integer);
14028 Check_Digits_Expression (Digs_Expr);
14029 Digs_Val := Expr_Value (Digs_Expr);
14031 if Digs_Val > 18 then
14032 Digs_Val := UI_From_Int (+18);
14033 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
14036 Set_Digits_Value (Implicit_Base, Digs_Val);
14037 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
14039 -- Set range of base type from digits value for now. This will be
14040 -- expanded to represent the true underlying base range by Freeze.
14042 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
14044 -- Note: We leave size as zero for now, size will be set at freeze
14045 -- time. We have to do this for ordinary fixed-point, because the size
14046 -- depends on the specified small, and we might as well do the same for
14047 -- decimal fixed-point.
14049 pragma Assert (Esize (Implicit_Base) = Uint_0);
14051 -- If there are bounds given in the declaration use them as the
14052 -- bounds of the first named subtype.
14054 if Present (Real_Range_Specification (Def)) then
14056 RRS : constant Node_Id := Real_Range_Specification (Def);
14057 Low : constant Node_Id := Low_Bound (RRS);
14058 High : constant Node_Id := High_Bound (RRS);
14063 Analyze_And_Resolve (Low, Any_Real);
14064 Analyze_And_Resolve (High, Any_Real);
14065 Check_Real_Bound (Low);
14066 Check_Real_Bound (High);
14067 Low_Val := Expr_Value_R (Low);
14068 High_Val := Expr_Value_R (High);
14070 if Low_Val < (-Bound_Val) then
14072 ("range low bound too small for digits value", Low);
14073 Low_Val := -Bound_Val;
14076 if High_Val > Bound_Val then
14078 ("range high bound too large for digits value", High);
14079 High_Val := Bound_Val;
14082 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
14085 -- If no explicit range, use range that corresponds to given
14086 -- digits value. This will end up as the final range for the
14090 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
14093 -- Complete entity for first subtype. The inheritance of the rep item
14094 -- chain ensures that SPARK-related pragmas are not clobbered when the
14095 -- decimal fixed point type acts as a full view of a private type.
14097 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
14098 Set_Etype (T, Implicit_Base);
14099 Set_Size_Info (T, Implicit_Base);
14100 Inherit_Rep_Item_Chain (T, Implicit_Base);
14101 Set_Digits_Value (T, Digs_Val);
14102 Set_Delta_Value (T, Delta_Val);
14103 Set_Small_Value (T, Delta_Val);
14104 Set_Scale_Value (T, Scale_Val);
14105 Set_Is_Constrained (T);
14106 end Decimal_Fixed_Point_Type_Declaration;
14108 -----------------------------------
14109 -- Derive_Progenitor_Subprograms --
14110 -----------------------------------
14112 procedure Derive_Progenitor_Subprograms
14113 (Parent_Type : Entity_Id;
14114 Tagged_Type : Entity_Id)
14119 Iface_Elmt : Elmt_Id;
14120 Iface_Subp : Entity_Id;
14121 New_Subp : Entity_Id := Empty;
14122 Prim_Elmt : Elmt_Id;
14127 pragma Assert (Ada_Version >= Ada_2005
14128 and then Is_Record_Type (Tagged_Type)
14129 and then Is_Tagged_Type (Tagged_Type)
14130 and then Has_Interfaces (Tagged_Type));
14132 -- Step 1: Transfer to the full-view primitives associated with the
14133 -- partial-view that cover interface primitives. Conceptually this
14134 -- work should be done later by Process_Full_View; done here to
14135 -- simplify its implementation at later stages. It can be safely
14136 -- done here because interfaces must be visible in the partial and
14137 -- private view (RM 7.3(7.3/2)).
14139 -- Small optimization: This work is only required if the parent may
14140 -- have entities whose Alias attribute reference an interface primitive.
14141 -- Such a situation may occur if the parent is an abstract type and the
14142 -- primitive has not been yet overridden or if the parent is a generic
14143 -- formal type covering interfaces.
14145 -- If the tagged type is not abstract, it cannot have abstract
14146 -- primitives (the only entities in the list of primitives of
14147 -- non-abstract tagged types that can reference abstract primitives
14148 -- through its Alias attribute are the internal entities that have
14149 -- attribute Interface_Alias, and these entities are generated later
14150 -- by Add_Internal_Interface_Entities).
14152 if In_Private_Part (Current_Scope)
14153 and then (Is_Abstract_Type (Parent_Type)
14155 Is_Generic_Type (Parent_Type))
14157 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
14158 while Present (Elmt) loop
14159 Subp := Node (Elmt);
14161 -- At this stage it is not possible to have entities in the list
14162 -- of primitives that have attribute Interface_Alias.
14164 pragma Assert (No (Interface_Alias (Subp)));
14166 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
14168 if Is_Interface (Typ) then
14169 E := Find_Primitive_Covering_Interface
14170 (Tagged_Type => Tagged_Type,
14171 Iface_Prim => Subp);
14174 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
14176 Replace_Elmt (Elmt, E);
14177 Remove_Homonym (Subp);
14185 -- Step 2: Add primitives of progenitors that are not implemented by
14186 -- parents of Tagged_Type.
14188 if Present (Interfaces (Base_Type (Tagged_Type))) then
14189 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
14190 while Present (Iface_Elmt) loop
14191 Iface := Node (Iface_Elmt);
14193 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
14194 while Present (Prim_Elmt) loop
14195 Iface_Subp := Node (Prim_Elmt);
14197 -- Exclude derivation of predefined primitives except those
14198 -- that come from source, or are inherited from one that comes
14199 -- from source. Required to catch declarations of equality
14200 -- operators of interfaces. For example:
14202 -- type Iface is interface;
14203 -- function "=" (Left, Right : Iface) return Boolean;
14205 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
14206 or else Comes_From_Source (Ultimate_Alias (Iface_Subp))
14208 E := Find_Primitive_Covering_Interface
14209 (Tagged_Type => Tagged_Type,
14210 Iface_Prim => Iface_Subp);
14212 -- If not found we derive a new primitive leaving its alias
14213 -- attribute referencing the interface primitive.
14217 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14219 -- Ada 2012 (AI05-0197): If the covering primitive's name
14220 -- differs from the name of the interface primitive then it
14221 -- is a private primitive inherited from a parent type. In
14222 -- such case, given that Tagged_Type covers the interface,
14223 -- the inherited private primitive becomes visible. For such
14224 -- purpose we add a new entity that renames the inherited
14225 -- private primitive.
14227 elsif Chars (E) /= Chars (Iface_Subp) then
14228 pragma Assert (Has_Suffix (E, 'P'));
14230 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14231 Set_Alias (New_Subp, E);
14232 Set_Is_Abstract_Subprogram (New_Subp,
14233 Is_Abstract_Subprogram (E));
14235 -- Propagate to the full view interface entities associated
14236 -- with the partial view.
14238 elsif In_Private_Part (Current_Scope)
14239 and then Present (Alias (E))
14240 and then Alias (E) = Iface_Subp
14242 List_Containing (Parent (E)) /=
14243 Private_Declarations
14245 (Unit_Declaration_Node (Current_Scope)))
14247 Append_Elmt (E, Primitive_Operations (Tagged_Type));
14251 Next_Elmt (Prim_Elmt);
14254 Next_Elmt (Iface_Elmt);
14257 end Derive_Progenitor_Subprograms;
14259 -----------------------
14260 -- Derive_Subprogram --
14261 -----------------------
14263 procedure Derive_Subprogram
14264 (New_Subp : in out Entity_Id;
14265 Parent_Subp : Entity_Id;
14266 Derived_Type : Entity_Id;
14267 Parent_Type : Entity_Id;
14268 Actual_Subp : Entity_Id := Empty)
14270 Formal : Entity_Id;
14271 -- Formal parameter of parent primitive operation
14273 Formal_Of_Actual : Entity_Id;
14274 -- Formal parameter of actual operation, when the derivation is to
14275 -- create a renaming for a primitive operation of an actual in an
14278 New_Formal : Entity_Id;
14279 -- Formal of inherited operation
14281 Visible_Subp : Entity_Id := Parent_Subp;
14283 function Is_Private_Overriding return Boolean;
14284 -- If Subp is a private overriding of a visible operation, the inherited
14285 -- operation derives from the overridden op (even though its body is the
14286 -- overriding one) and the inherited operation is visible now. See
14287 -- sem_disp to see the full details of the handling of the overridden
14288 -- subprogram, which is removed from the list of primitive operations of
14289 -- the type. The overridden subprogram is saved locally in Visible_Subp,
14290 -- and used to diagnose abstract operations that need overriding in the
14293 procedure Replace_Type (Id, New_Id : Entity_Id);
14294 -- When the type is an anonymous access type, create a new access type
14295 -- designating the derived type.
14297 procedure Set_Derived_Name;
14298 -- This procedure sets the appropriate Chars name for New_Subp. This
14299 -- is normally just a copy of the parent name. An exception arises for
14300 -- type support subprograms, where the name is changed to reflect the
14301 -- name of the derived type, e.g. if type foo is derived from type bar,
14302 -- then a procedure barDA is derived with a name fooDA.
14304 ---------------------------
14305 -- Is_Private_Overriding --
14306 ---------------------------
14308 function Is_Private_Overriding return Boolean is
14312 -- If the parent is not a dispatching operation there is no
14313 -- need to investigate overridings
14315 if not Is_Dispatching_Operation (Parent_Subp) then
14319 -- The visible operation that is overridden is a homonym of the
14320 -- parent subprogram. We scan the homonym chain to find the one
14321 -- whose alias is the subprogram we are deriving.
14323 Prev := Current_Entity (Parent_Subp);
14324 while Present (Prev) loop
14325 if Ekind (Prev) = Ekind (Parent_Subp)
14326 and then Alias (Prev) = Parent_Subp
14327 and then Scope (Parent_Subp) = Scope (Prev)
14328 and then not Is_Hidden (Prev)
14330 Visible_Subp := Prev;
14334 Prev := Homonym (Prev);
14338 end Is_Private_Overriding;
14344 procedure Replace_Type (Id, New_Id : Entity_Id) is
14345 Id_Type : constant Entity_Id := Etype (Id);
14346 Acc_Type : Entity_Id;
14347 Par : constant Node_Id := Parent (Derived_Type);
14350 -- When the type is an anonymous access type, create a new access
14351 -- type designating the derived type. This itype must be elaborated
14352 -- at the point of the derivation, not on subsequent calls that may
14353 -- be out of the proper scope for Gigi, so we insert a reference to
14354 -- it after the derivation.
14356 if Ekind (Id_Type) = E_Anonymous_Access_Type then
14358 Desig_Typ : Entity_Id := Designated_Type (Id_Type);
14361 if Ekind (Desig_Typ) = E_Record_Type_With_Private
14362 and then Present (Full_View (Desig_Typ))
14363 and then not Is_Private_Type (Parent_Type)
14365 Desig_Typ := Full_View (Desig_Typ);
14368 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
14370 -- Ada 2005 (AI-251): Handle also derivations of abstract
14371 -- interface primitives.
14373 or else (Is_Interface (Desig_Typ)
14374 and then not Is_Class_Wide_Type (Desig_Typ))
14376 Acc_Type := New_Copy (Id_Type);
14377 Set_Etype (Acc_Type, Acc_Type);
14378 Set_Scope (Acc_Type, New_Subp);
14380 -- Set size of anonymous access type. If we have an access
14381 -- to an unconstrained array, this is a fat pointer, so it
14382 -- is sizes at twice addtress size.
14384 if Is_Array_Type (Desig_Typ)
14385 and then not Is_Constrained (Desig_Typ)
14387 Init_Size (Acc_Type, 2 * System_Address_Size);
14389 -- Other cases use a thin pointer
14392 Init_Size (Acc_Type, System_Address_Size);
14395 -- Set remaining characterstics of anonymous access type
14397 Init_Alignment (Acc_Type);
14398 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
14400 Set_Etype (New_Id, Acc_Type);
14401 Set_Scope (New_Id, New_Subp);
14403 -- Create a reference to it
14405 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
14408 Set_Etype (New_Id, Id_Type);
14412 -- In Ada2012, a formal may have an incomplete type but the type
14413 -- derivation that inherits the primitive follows the full view.
14415 elsif Base_Type (Id_Type) = Base_Type (Parent_Type)
14417 (Ekind (Id_Type) = E_Record_Type_With_Private
14418 and then Present (Full_View (Id_Type))
14420 Base_Type (Full_View (Id_Type)) = Base_Type (Parent_Type))
14422 (Ada_Version >= Ada_2012
14423 and then Ekind (Id_Type) = E_Incomplete_Type
14424 and then Full_View (Id_Type) = Parent_Type)
14426 -- Constraint checks on formals are generated during expansion,
14427 -- based on the signature of the original subprogram. The bounds
14428 -- of the derived type are not relevant, and thus we can use
14429 -- the base type for the formals. However, the return type may be
14430 -- used in a context that requires that the proper static bounds
14431 -- be used (a case statement, for example) and for those cases
14432 -- we must use the derived type (first subtype), not its base.
14434 -- If the derived_type_definition has no constraints, we know that
14435 -- the derived type has the same constraints as the first subtype
14436 -- of the parent, and we can also use it rather than its base,
14437 -- which can lead to more efficient code.
14439 if Etype (Id) = Parent_Type then
14440 if Is_Scalar_Type (Parent_Type)
14442 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
14444 Set_Etype (New_Id, Derived_Type);
14446 elsif Nkind (Par) = N_Full_Type_Declaration
14448 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
14451 (Subtype_Indication (Type_Definition (Par)))
14453 Set_Etype (New_Id, Derived_Type);
14456 Set_Etype (New_Id, Base_Type (Derived_Type));
14460 Set_Etype (New_Id, Base_Type (Derived_Type));
14464 Set_Etype (New_Id, Etype (Id));
14468 ----------------------
14469 -- Set_Derived_Name --
14470 ----------------------
14472 procedure Set_Derived_Name is
14473 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
14475 if Nm = TSS_Null then
14476 Set_Chars (New_Subp, Chars (Parent_Subp));
14478 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
14480 end Set_Derived_Name;
14482 -- Start of processing for Derive_Subprogram
14485 New_Subp := New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
14486 Set_Ekind (New_Subp, Ekind (Parent_Subp));
14487 Set_Contract (New_Subp, Make_Contract (Sloc (New_Subp)));
14489 -- Check whether the inherited subprogram is a private operation that
14490 -- should be inherited but not yet made visible. Such subprograms can
14491 -- become visible at a later point (e.g., the private part of a public
14492 -- child unit) via Declare_Inherited_Private_Subprograms. If the
14493 -- following predicate is true, then this is not such a private
14494 -- operation and the subprogram simply inherits the name of the parent
14495 -- subprogram. Note the special check for the names of controlled
14496 -- operations, which are currently exempted from being inherited with
14497 -- a hidden name because they must be findable for generation of
14498 -- implicit run-time calls.
14500 if not Is_Hidden (Parent_Subp)
14501 or else Is_Internal (Parent_Subp)
14502 or else Is_Private_Overriding
14503 or else Is_Internal_Name (Chars (Parent_Subp))
14504 or else Nam_In (Chars (Parent_Subp), Name_Initialize,
14510 -- An inherited dispatching equality will be overridden by an internally
14511 -- generated one, or by an explicit one, so preserve its name and thus
14512 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
14513 -- private operation it may become invisible if the full view has
14514 -- progenitors, and the dispatch table will be malformed.
14515 -- We check that the type is limited to handle the anomalous declaration
14516 -- of Limited_Controlled, which is derived from a non-limited type, and
14517 -- which is handled specially elsewhere as well.
14519 elsif Chars (Parent_Subp) = Name_Op_Eq
14520 and then Is_Dispatching_Operation (Parent_Subp)
14521 and then Etype (Parent_Subp) = Standard_Boolean
14522 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
14524 Etype (First_Formal (Parent_Subp)) =
14525 Etype (Next_Formal (First_Formal (Parent_Subp)))
14529 -- If parent is hidden, this can be a regular derivation if the
14530 -- parent is immediately visible in a non-instantiating context,
14531 -- or if we are in the private part of an instance. This test
14532 -- should still be refined ???
14534 -- The test for In_Instance_Not_Visible avoids inheriting the derived
14535 -- operation as a non-visible operation in cases where the parent
14536 -- subprogram might not be visible now, but was visible within the
14537 -- original generic, so it would be wrong to make the inherited
14538 -- subprogram non-visible now. (Not clear if this test is fully
14539 -- correct; are there any cases where we should declare the inherited
14540 -- operation as not visible to avoid it being overridden, e.g., when
14541 -- the parent type is a generic actual with private primitives ???)
14543 -- (they should be treated the same as other private inherited
14544 -- subprograms, but it's not clear how to do this cleanly). ???
14546 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
14547 and then Is_Immediately_Visible (Parent_Subp)
14548 and then not In_Instance)
14549 or else In_Instance_Not_Visible
14553 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
14554 -- overrides an interface primitive because interface primitives
14555 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
14557 elsif Ada_Version >= Ada_2005
14558 and then Is_Dispatching_Operation (Parent_Subp)
14559 and then Covers_Some_Interface (Parent_Subp)
14563 -- Otherwise, the type is inheriting a private operation, so enter
14564 -- it with a special name so it can't be overridden.
14567 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
14570 Set_Parent (New_Subp, Parent (Derived_Type));
14572 if Present (Actual_Subp) then
14573 Replace_Type (Actual_Subp, New_Subp);
14575 Replace_Type (Parent_Subp, New_Subp);
14578 Conditional_Delay (New_Subp, Parent_Subp);
14580 -- If we are creating a renaming for a primitive operation of an
14581 -- actual of a generic derived type, we must examine the signature
14582 -- of the actual primitive, not that of the generic formal, which for
14583 -- example may be an interface. However the name and initial value
14584 -- of the inherited operation are those of the formal primitive.
14586 Formal := First_Formal (Parent_Subp);
14588 if Present (Actual_Subp) then
14589 Formal_Of_Actual := First_Formal (Actual_Subp);
14591 Formal_Of_Actual := Empty;
14594 while Present (Formal) loop
14595 New_Formal := New_Copy (Formal);
14597 -- Normally we do not go copying parents, but in the case of
14598 -- formals, we need to link up to the declaration (which is the
14599 -- parameter specification), and it is fine to link up to the
14600 -- original formal's parameter specification in this case.
14602 Set_Parent (New_Formal, Parent (Formal));
14603 Append_Entity (New_Formal, New_Subp);
14605 if Present (Formal_Of_Actual) then
14606 Replace_Type (Formal_Of_Actual, New_Formal);
14607 Next_Formal (Formal_Of_Actual);
14609 Replace_Type (Formal, New_Formal);
14612 Next_Formal (Formal);
14615 -- If this derivation corresponds to a tagged generic actual, then
14616 -- primitive operations rename those of the actual. Otherwise the
14617 -- primitive operations rename those of the parent type, If the parent
14618 -- renames an intrinsic operator, so does the new subprogram. We except
14619 -- concatenation, which is always properly typed, and does not get
14620 -- expanded as other intrinsic operations.
14622 if No (Actual_Subp) then
14623 if Is_Intrinsic_Subprogram (Parent_Subp) then
14624 Set_Is_Intrinsic_Subprogram (New_Subp);
14626 if Present (Alias (Parent_Subp))
14627 and then Chars (Parent_Subp) /= Name_Op_Concat
14629 Set_Alias (New_Subp, Alias (Parent_Subp));
14631 Set_Alias (New_Subp, Parent_Subp);
14635 Set_Alias (New_Subp, Parent_Subp);
14639 Set_Alias (New_Subp, Actual_Subp);
14642 -- Inherit the "ghostness" from the parent subprogram
14644 if Is_Ghost_Entity (Alias (New_Subp)) then
14645 Set_Is_Ghost_Entity (New_Subp);
14648 -- Derived subprograms of a tagged type must inherit the convention
14649 -- of the parent subprogram (a requirement of AI-117). Derived
14650 -- subprograms of untagged types simply get convention Ada by default.
14652 -- If the derived type is a tagged generic formal type with unknown
14653 -- discriminants, its convention is intrinsic (RM 6.3.1 (8)).
14655 -- However, if the type is derived from a generic formal, the further
14656 -- inherited subprogram has the convention of the non-generic ancestor.
14657 -- Otherwise there would be no way to override the operation.
14658 -- (This is subject to forthcoming ARG discussions).
14660 if Is_Tagged_Type (Derived_Type) then
14661 if Is_Generic_Type (Derived_Type)
14662 and then Has_Unknown_Discriminants (Derived_Type)
14664 Set_Convention (New_Subp, Convention_Intrinsic);
14667 if Is_Generic_Type (Parent_Type)
14668 and then Has_Unknown_Discriminants (Parent_Type)
14670 Set_Convention (New_Subp, Convention (Alias (Parent_Subp)));
14672 Set_Convention (New_Subp, Convention (Parent_Subp));
14677 -- Predefined controlled operations retain their name even if the parent
14678 -- is hidden (see above), but they are not primitive operations if the
14679 -- ancestor is not visible, for example if the parent is a private
14680 -- extension completed with a controlled extension. Note that a full
14681 -- type that is controlled can break privacy: the flag Is_Controlled is
14682 -- set on both views of the type.
14684 if Is_Controlled (Parent_Type)
14685 and then Nam_In (Chars (Parent_Subp), Name_Initialize,
14688 and then Is_Hidden (Parent_Subp)
14689 and then not Is_Visibly_Controlled (Parent_Type)
14691 Set_Is_Hidden (New_Subp);
14694 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
14695 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
14697 if Ekind (Parent_Subp) = E_Procedure then
14698 Set_Is_Valued_Procedure
14699 (New_Subp, Is_Valued_Procedure (Parent_Subp));
14701 Set_Has_Controlling_Result
14702 (New_Subp, Has_Controlling_Result (Parent_Subp));
14705 -- No_Return must be inherited properly. If this is overridden in the
14706 -- case of a dispatching operation, then a check is made in Sem_Disp
14707 -- that the overriding operation is also No_Return (no such check is
14708 -- required for the case of non-dispatching operation.
14710 Set_No_Return (New_Subp, No_Return (Parent_Subp));
14712 -- A derived function with a controlling result is abstract. If the
14713 -- Derived_Type is a nonabstract formal generic derived type, then
14714 -- inherited operations are not abstract: the required check is done at
14715 -- instantiation time. If the derivation is for a generic actual, the
14716 -- function is not abstract unless the actual is.
14718 if Is_Generic_Type (Derived_Type)
14719 and then not Is_Abstract_Type (Derived_Type)
14723 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
14724 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
14726 -- A subprogram subject to pragma Extensions_Visible with value False
14727 -- requires overriding if the subprogram has at least one controlling
14728 -- OUT parameter (SPARK RM 6.1.7(6)).
14730 elsif Ada_Version >= Ada_2005
14731 and then (Is_Abstract_Subprogram (Alias (New_Subp))
14732 or else (Is_Tagged_Type (Derived_Type)
14733 and then Etype (New_Subp) = Derived_Type
14734 and then not Is_Null_Extension (Derived_Type))
14735 or else (Is_Tagged_Type (Derived_Type)
14736 and then Ekind (Etype (New_Subp)) =
14737 E_Anonymous_Access_Type
14738 and then Designated_Type (Etype (New_Subp)) =
14740 and then not Is_Null_Extension (Derived_Type))
14741 or else (Comes_From_Source (Alias (New_Subp))
14742 and then Is_EVF_Procedure (Alias (New_Subp))))
14743 and then No (Actual_Subp)
14745 if not Is_Tagged_Type (Derived_Type)
14746 or else Is_Abstract_Type (Derived_Type)
14747 or else Is_Abstract_Subprogram (Alias (New_Subp))
14749 Set_Is_Abstract_Subprogram (New_Subp);
14751 Set_Requires_Overriding (New_Subp);
14754 elsif Ada_Version < Ada_2005
14755 and then (Is_Abstract_Subprogram (Alias (New_Subp))
14756 or else (Is_Tagged_Type (Derived_Type)
14757 and then Etype (New_Subp) = Derived_Type
14758 and then No (Actual_Subp)))
14760 Set_Is_Abstract_Subprogram (New_Subp);
14762 -- AI05-0097 : an inherited operation that dispatches on result is
14763 -- abstract if the derived type is abstract, even if the parent type
14764 -- is concrete and the derived type is a null extension.
14766 elsif Has_Controlling_Result (Alias (New_Subp))
14767 and then Is_Abstract_Type (Etype (New_Subp))
14769 Set_Is_Abstract_Subprogram (New_Subp);
14771 -- Finally, if the parent type is abstract we must verify that all
14772 -- inherited operations are either non-abstract or overridden, or that
14773 -- the derived type itself is abstract (this check is performed at the
14774 -- end of a package declaration, in Check_Abstract_Overriding). A
14775 -- private overriding in the parent type will not be visible in the
14776 -- derivation if we are not in an inner package or in a child unit of
14777 -- the parent type, in which case the abstractness of the inherited
14778 -- operation is carried to the new subprogram.
14780 elsif Is_Abstract_Type (Parent_Type)
14781 and then not In_Open_Scopes (Scope (Parent_Type))
14782 and then Is_Private_Overriding
14783 and then Is_Abstract_Subprogram (Visible_Subp)
14785 if No (Actual_Subp) then
14786 Set_Alias (New_Subp, Visible_Subp);
14787 Set_Is_Abstract_Subprogram (New_Subp, True);
14790 -- If this is a derivation for an instance of a formal derived
14791 -- type, abstractness comes from the primitive operation of the
14792 -- actual, not from the operation inherited from the ancestor.
14794 Set_Is_Abstract_Subprogram
14795 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
14799 New_Overloaded_Entity (New_Subp, Derived_Type);
14801 -- Check for case of a derived subprogram for the instantiation of a
14802 -- formal derived tagged type, if so mark the subprogram as dispatching
14803 -- and inherit the dispatching attributes of the actual subprogram. The
14804 -- derived subprogram is effectively renaming of the actual subprogram,
14805 -- so it needs to have the same attributes as the actual.
14807 if Present (Actual_Subp)
14808 and then Is_Dispatching_Operation (Actual_Subp)
14810 Set_Is_Dispatching_Operation (New_Subp);
14812 if Present (DTC_Entity (Actual_Subp)) then
14813 Set_DTC_Entity (New_Subp, DTC_Entity (Actual_Subp));
14814 Set_DT_Position (New_Subp, DT_Position (Actual_Subp));
14818 -- Indicate that a derived subprogram does not require a body and that
14819 -- it does not require processing of default expressions.
14821 Set_Has_Completion (New_Subp);
14822 Set_Default_Expressions_Processed (New_Subp);
14824 if Ekind (New_Subp) = E_Function then
14825 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
14827 end Derive_Subprogram;
14829 ------------------------
14830 -- Derive_Subprograms --
14831 ------------------------
14833 procedure Derive_Subprograms
14834 (Parent_Type : Entity_Id;
14835 Derived_Type : Entity_Id;
14836 Generic_Actual : Entity_Id := Empty)
14838 Op_List : constant Elist_Id :=
14839 Collect_Primitive_Operations (Parent_Type);
14841 function Check_Derived_Type return Boolean;
14842 -- Check that all the entities derived from Parent_Type are found in
14843 -- the list of primitives of Derived_Type exactly in the same order.
14845 procedure Derive_Interface_Subprogram
14846 (New_Subp : in out Entity_Id;
14848 Actual_Subp : Entity_Id);
14849 -- Derive New_Subp from the ultimate alias of the parent subprogram Subp
14850 -- (which is an interface primitive). If Generic_Actual is present then
14851 -- Actual_Subp is the actual subprogram corresponding with the generic
14852 -- subprogram Subp.
14854 function Check_Derived_Type return Boolean is
14858 New_Subp : Entity_Id;
14863 -- Traverse list of entities in the current scope searching for
14864 -- an incomplete type whose full-view is derived type
14866 E := First_Entity (Scope (Derived_Type));
14867 while Present (E) and then E /= Derived_Type loop
14868 if Ekind (E) = E_Incomplete_Type
14869 and then Present (Full_View (E))
14870 and then Full_View (E) = Derived_Type
14872 -- Disable this test if Derived_Type completes an incomplete
14873 -- type because in such case more primitives can be added
14874 -- later to the list of primitives of Derived_Type by routine
14875 -- Process_Incomplete_Dependents
14880 E := Next_Entity (E);
14883 List := Collect_Primitive_Operations (Derived_Type);
14884 Elmt := First_Elmt (List);
14886 Op_Elmt := First_Elmt (Op_List);
14887 while Present (Op_Elmt) loop
14888 Subp := Node (Op_Elmt);
14889 New_Subp := Node (Elmt);
14891 -- At this early stage Derived_Type has no entities with attribute
14892 -- Interface_Alias. In addition, such primitives are always
14893 -- located at the end of the list of primitives of Parent_Type.
14894 -- Therefore, if found we can safely stop processing pending
14897 exit when Present (Interface_Alias (Subp));
14899 -- Handle hidden entities
14901 if not Is_Predefined_Dispatching_Operation (Subp)
14902 and then Is_Hidden (Subp)
14904 if Present (New_Subp)
14905 and then Primitive_Names_Match (Subp, New_Subp)
14911 if not Present (New_Subp)
14912 or else Ekind (Subp) /= Ekind (New_Subp)
14913 or else not Primitive_Names_Match (Subp, New_Subp)
14921 Next_Elmt (Op_Elmt);
14925 end Check_Derived_Type;
14927 ---------------------------------
14928 -- Derive_Interface_Subprogram --
14929 ---------------------------------
14931 procedure Derive_Interface_Subprogram
14932 (New_Subp : in out Entity_Id;
14934 Actual_Subp : Entity_Id)
14936 Iface_Subp : constant Entity_Id := Ultimate_Alias (Subp);
14937 Iface_Type : constant Entity_Id := Find_Dispatching_Type (Iface_Subp);
14940 pragma Assert (Is_Interface (Iface_Type));
14943 (New_Subp => New_Subp,
14944 Parent_Subp => Iface_Subp,
14945 Derived_Type => Derived_Type,
14946 Parent_Type => Iface_Type,
14947 Actual_Subp => Actual_Subp);
14949 -- Given that this new interface entity corresponds with a primitive
14950 -- of the parent that was not overridden we must leave it associated
14951 -- with its parent primitive to ensure that it will share the same
14952 -- dispatch table slot when overridden.
14954 if No (Actual_Subp) then
14955 Set_Alias (New_Subp, Subp);
14957 -- For instantiations this is not needed since the previous call to
14958 -- Derive_Subprogram leaves the entity well decorated.
14961 pragma Assert (Alias (New_Subp) = Actual_Subp);
14964 end Derive_Interface_Subprogram;
14968 Alias_Subp : Entity_Id;
14969 Act_List : Elist_Id;
14970 Act_Elmt : Elmt_Id;
14971 Act_Subp : Entity_Id := Empty;
14973 Need_Search : Boolean := False;
14974 New_Subp : Entity_Id := Empty;
14975 Parent_Base : Entity_Id;
14978 -- Start of processing for Derive_Subprograms
14981 if Ekind (Parent_Type) = E_Record_Type_With_Private
14982 and then Has_Discriminants (Parent_Type)
14983 and then Present (Full_View (Parent_Type))
14985 Parent_Base := Full_View (Parent_Type);
14987 Parent_Base := Parent_Type;
14990 if Present (Generic_Actual) then
14991 Act_List := Collect_Primitive_Operations (Generic_Actual);
14992 Act_Elmt := First_Elmt (Act_List);
14994 Act_List := No_Elist;
14995 Act_Elmt := No_Elmt;
14998 -- Derive primitives inherited from the parent. Note that if the generic
14999 -- actual is present, this is not really a type derivation, it is a
15000 -- completion within an instance.
15002 -- Case 1: Derived_Type does not implement interfaces
15004 if not Is_Tagged_Type (Derived_Type)
15005 or else (not Has_Interfaces (Derived_Type)
15006 and then not (Present (Generic_Actual)
15007 and then Has_Interfaces (Generic_Actual)))
15009 Elmt := First_Elmt (Op_List);
15010 while Present (Elmt) loop
15011 Subp := Node (Elmt);
15013 -- Literals are derived earlier in the process of building the
15014 -- derived type, and are skipped here.
15016 if Ekind (Subp) = E_Enumeration_Literal then
15019 -- The actual is a direct descendant and the common primitive
15020 -- operations appear in the same order.
15022 -- If the generic parent type is present, the derived type is an
15023 -- instance of a formal derived type, and within the instance its
15024 -- operations are those of the actual. We derive from the formal
15025 -- type but make the inherited operations aliases of the
15026 -- corresponding operations of the actual.
15029 pragma Assert (No (Node (Act_Elmt))
15030 or else (Primitive_Names_Match (Subp, Node (Act_Elmt))
15033 (Subp, Node (Act_Elmt),
15034 Skip_Controlling_Formals => True)));
15037 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
15039 if Present (Act_Elmt) then
15040 Next_Elmt (Act_Elmt);
15047 -- Case 2: Derived_Type implements interfaces
15050 -- If the parent type has no predefined primitives we remove
15051 -- predefined primitives from the list of primitives of generic
15052 -- actual to simplify the complexity of this algorithm.
15054 if Present (Generic_Actual) then
15056 Has_Predefined_Primitives : Boolean := False;
15059 -- Check if the parent type has predefined primitives
15061 Elmt := First_Elmt (Op_List);
15062 while Present (Elmt) loop
15063 Subp := Node (Elmt);
15065 if Is_Predefined_Dispatching_Operation (Subp)
15066 and then not Comes_From_Source (Ultimate_Alias (Subp))
15068 Has_Predefined_Primitives := True;
15075 -- Remove predefined primitives of Generic_Actual. We must use
15076 -- an auxiliary list because in case of tagged types the value
15077 -- returned by Collect_Primitive_Operations is the value stored
15078 -- in its Primitive_Operations attribute (and we don't want to
15079 -- modify its current contents).
15081 if not Has_Predefined_Primitives then
15083 Aux_List : constant Elist_Id := New_Elmt_List;
15086 Elmt := First_Elmt (Act_List);
15087 while Present (Elmt) loop
15088 Subp := Node (Elmt);
15090 if not Is_Predefined_Dispatching_Operation (Subp)
15091 or else Comes_From_Source (Subp)
15093 Append_Elmt (Subp, Aux_List);
15099 Act_List := Aux_List;
15103 Act_Elmt := First_Elmt (Act_List);
15104 Act_Subp := Node (Act_Elmt);
15108 -- Stage 1: If the generic actual is not present we derive the
15109 -- primitives inherited from the parent type. If the generic parent
15110 -- type is present, the derived type is an instance of a formal
15111 -- derived type, and within the instance its operations are those of
15112 -- the actual. We derive from the formal type but make the inherited
15113 -- operations aliases of the corresponding operations of the actual.
15115 Elmt := First_Elmt (Op_List);
15116 while Present (Elmt) loop
15117 Subp := Node (Elmt);
15118 Alias_Subp := Ultimate_Alias (Subp);
15120 -- Do not derive internal entities of the parent that link
15121 -- interface primitives with their covering primitive. These
15122 -- entities will be added to this type when frozen.
15124 if Present (Interface_Alias (Subp)) then
15128 -- If the generic actual is present find the corresponding
15129 -- operation in the generic actual. If the parent type is a
15130 -- direct ancestor of the derived type then, even if it is an
15131 -- interface, the operations are inherited from the primary
15132 -- dispatch table and are in the proper order. If we detect here
15133 -- that primitives are not in the same order we traverse the list
15134 -- of primitive operations of the actual to find the one that
15135 -- implements the interface primitive.
15139 (Present (Generic_Actual)
15140 and then Present (Act_Subp)
15142 (Primitive_Names_Match (Subp, Act_Subp)
15144 Type_Conformant (Subp, Act_Subp,
15145 Skip_Controlling_Formals => True)))
15147 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual,
15148 Use_Full_View => True));
15150 -- Remember that we need searching for all pending primitives
15152 Need_Search := True;
15154 -- Handle entities associated with interface primitives
15156 if Present (Alias_Subp)
15157 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
15158 and then not Is_Predefined_Dispatching_Operation (Subp)
15160 -- Search for the primitive in the homonym chain
15163 Find_Primitive_Covering_Interface
15164 (Tagged_Type => Generic_Actual,
15165 Iface_Prim => Alias_Subp);
15167 -- Previous search may not locate primitives covering
15168 -- interfaces defined in generics units or instantiations.
15169 -- (it fails if the covering primitive has formals whose
15170 -- type is also defined in generics or instantiations).
15171 -- In such case we search in the list of primitives of the
15172 -- generic actual for the internal entity that links the
15173 -- interface primitive and the covering primitive.
15176 and then Is_Generic_Type (Parent_Type)
15178 -- This code has been designed to handle only generic
15179 -- formals that implement interfaces that are defined
15180 -- in a generic unit or instantiation. If this code is
15181 -- needed for other cases we must review it because
15182 -- (given that it relies on Original_Location to locate
15183 -- the primitive of Generic_Actual that covers the
15184 -- interface) it could leave linked through attribute
15185 -- Alias entities of unrelated instantiations).
15189 (Scope (Find_Dispatching_Type (Alias_Subp)))
15191 Instantiation_Depth
15192 (Sloc (Find_Dispatching_Type (Alias_Subp))) > 0);
15195 Iface_Prim_Loc : constant Source_Ptr :=
15196 Original_Location (Sloc (Alias_Subp));
15203 First_Elmt (Primitive_Operations (Generic_Actual));
15205 Search : while Present (Elmt) loop
15206 Prim := Node (Elmt);
15208 if Present (Interface_Alias (Prim))
15209 and then Original_Location
15210 (Sloc (Interface_Alias (Prim))) =
15213 Act_Subp := Alias (Prim);
15222 pragma Assert (Present (Act_Subp)
15223 or else Is_Abstract_Type (Generic_Actual)
15224 or else Serious_Errors_Detected > 0);
15226 -- Handle predefined primitives plus the rest of user-defined
15230 Act_Elmt := First_Elmt (Act_List);
15231 while Present (Act_Elmt) loop
15232 Act_Subp := Node (Act_Elmt);
15234 exit when Primitive_Names_Match (Subp, Act_Subp)
15235 and then Type_Conformant
15237 Skip_Controlling_Formals => True)
15238 and then No (Interface_Alias (Act_Subp));
15240 Next_Elmt (Act_Elmt);
15243 if No (Act_Elmt) then
15249 -- Case 1: If the parent is a limited interface then it has the
15250 -- predefined primitives of synchronized interfaces. However, the
15251 -- actual type may be a non-limited type and hence it does not
15252 -- have such primitives.
15254 if Present (Generic_Actual)
15255 and then not Present (Act_Subp)
15256 and then Is_Limited_Interface (Parent_Base)
15257 and then Is_Predefined_Interface_Primitive (Subp)
15261 -- Case 2: Inherit entities associated with interfaces that were
15262 -- not covered by the parent type. We exclude here null interface
15263 -- primitives because they do not need special management.
15265 -- We also exclude interface operations that are renamings. If the
15266 -- subprogram is an explicit renaming of an interface primitive,
15267 -- it is a regular primitive operation, and the presence of its
15268 -- alias is not relevant: it has to be derived like any other
15271 elsif Present (Alias (Subp))
15272 and then Nkind (Unit_Declaration_Node (Subp)) /=
15273 N_Subprogram_Renaming_Declaration
15274 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
15276 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
15277 and then Null_Present (Parent (Alias_Subp)))
15279 -- If this is an abstract private type then we transfer the
15280 -- derivation of the interface primitive from the partial view
15281 -- to the full view. This is safe because all the interfaces
15282 -- must be visible in the partial view. Done to avoid adding
15283 -- a new interface derivation to the private part of the
15284 -- enclosing package; otherwise this new derivation would be
15285 -- decorated as hidden when the analysis of the enclosing
15286 -- package completes.
15288 if Is_Abstract_Type (Derived_Type)
15289 and then In_Private_Part (Current_Scope)
15290 and then Has_Private_Declaration (Derived_Type)
15293 Partial_View : Entity_Id;
15298 Partial_View := First_Entity (Current_Scope);
15300 exit when No (Partial_View)
15301 or else (Has_Private_Declaration (Partial_View)
15303 Full_View (Partial_View) = Derived_Type);
15305 Next_Entity (Partial_View);
15308 -- If the partial view was not found then the source code
15309 -- has errors and the derivation is not needed.
15311 if Present (Partial_View) then
15313 First_Elmt (Primitive_Operations (Partial_View));
15314 while Present (Elmt) loop
15315 Ent := Node (Elmt);
15317 if Present (Alias (Ent))
15318 and then Ultimate_Alias (Ent) = Alias (Subp)
15321 (Ent, Primitive_Operations (Derived_Type));
15328 -- If the interface primitive was not found in the
15329 -- partial view then this interface primitive was
15330 -- overridden. We add a derivation to activate in
15331 -- Derive_Progenitor_Subprograms the machinery to
15335 Derive_Interface_Subprogram
15336 (New_Subp => New_Subp,
15338 Actual_Subp => Act_Subp);
15343 Derive_Interface_Subprogram
15344 (New_Subp => New_Subp,
15346 Actual_Subp => Act_Subp);
15349 -- Case 3: Common derivation
15353 (New_Subp => New_Subp,
15354 Parent_Subp => Subp,
15355 Derived_Type => Derived_Type,
15356 Parent_Type => Parent_Base,
15357 Actual_Subp => Act_Subp);
15360 -- No need to update Act_Elm if we must search for the
15361 -- corresponding operation in the generic actual
15364 and then Present (Act_Elmt)
15366 Next_Elmt (Act_Elmt);
15367 Act_Subp := Node (Act_Elmt);
15374 -- Inherit additional operations from progenitors. If the derived
15375 -- type is a generic actual, there are not new primitive operations
15376 -- for the type because it has those of the actual, and therefore
15377 -- nothing needs to be done. The renamings generated above are not
15378 -- primitive operations, and their purpose is simply to make the
15379 -- proper operations visible within an instantiation.
15381 if No (Generic_Actual) then
15382 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
15386 -- Final check: Direct descendants must have their primitives in the
15387 -- same order. We exclude from this test untagged types and instances
15388 -- of formal derived types. We skip this test if we have already
15389 -- reported serious errors in the sources.
15391 pragma Assert (not Is_Tagged_Type (Derived_Type)
15392 or else Present (Generic_Actual)
15393 or else Serious_Errors_Detected > 0
15394 or else Check_Derived_Type);
15395 end Derive_Subprograms;
15397 --------------------------------
15398 -- Derived_Standard_Character --
15399 --------------------------------
15401 procedure Derived_Standard_Character
15403 Parent_Type : Entity_Id;
15404 Derived_Type : Entity_Id)
15406 Loc : constant Source_Ptr := Sloc (N);
15407 Def : constant Node_Id := Type_Definition (N);
15408 Indic : constant Node_Id := Subtype_Indication (Def);
15409 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
15410 Implicit_Base : constant Entity_Id :=
15412 (E_Enumeration_Type, N, Derived_Type, 'B');
15418 Discard_Node (Process_Subtype (Indic, N));
15420 Set_Etype (Implicit_Base, Parent_Base);
15421 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
15422 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
15424 Set_Is_Character_Type (Implicit_Base, True);
15425 Set_Has_Delayed_Freeze (Implicit_Base);
15427 -- The bounds of the implicit base are the bounds of the parent base.
15428 -- Note that their type is the parent base.
15430 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
15431 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
15433 Set_Scalar_Range (Implicit_Base,
15436 High_Bound => Hi));
15438 Conditional_Delay (Derived_Type, Parent_Type);
15440 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
15441 Set_Etype (Derived_Type, Implicit_Base);
15442 Set_Size_Info (Derived_Type, Parent_Type);
15444 if Unknown_RM_Size (Derived_Type) then
15445 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
15448 Set_Is_Character_Type (Derived_Type, True);
15450 if Nkind (Indic) /= N_Subtype_Indication then
15452 -- If no explicit constraint, the bounds are those
15453 -- of the parent type.
15455 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
15456 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
15457 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
15460 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
15462 -- Because the implicit base is used in the conversion of the bounds, we
15463 -- have to freeze it now. This is similar to what is done for numeric
15464 -- types, and it equally suspicious, but otherwise a non-static bound
15465 -- will have a reference to an unfrozen type, which is rejected by Gigi
15466 -- (???). This requires specific care for definition of stream
15467 -- attributes. For details, see comments at the end of
15468 -- Build_Derived_Numeric_Type.
15470 Freeze_Before (N, Implicit_Base);
15471 end Derived_Standard_Character;
15473 ------------------------------
15474 -- Derived_Type_Declaration --
15475 ------------------------------
15477 procedure Derived_Type_Declaration
15480 Is_Completion : Boolean)
15482 Parent_Type : Entity_Id;
15484 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
15485 -- Check whether the parent type is a generic formal, or derives
15486 -- directly or indirectly from one.
15488 ------------------------
15489 -- Comes_From_Generic --
15490 ------------------------
15492 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
15494 if Is_Generic_Type (Typ) then
15497 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
15500 elsif Is_Private_Type (Typ)
15501 and then Present (Full_View (Typ))
15502 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
15506 elsif Is_Generic_Actual_Type (Typ) then
15512 end Comes_From_Generic;
15516 Def : constant Node_Id := Type_Definition (N);
15517 Iface_Def : Node_Id;
15518 Indic : constant Node_Id := Subtype_Indication (Def);
15519 Extension : constant Node_Id := Record_Extension_Part (Def);
15520 Parent_Node : Node_Id;
15523 -- Start of processing for Derived_Type_Declaration
15526 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
15528 -- Ada 2005 (AI-251): In case of interface derivation check that the
15529 -- parent is also an interface.
15531 if Interface_Present (Def) then
15532 Check_SPARK_05_Restriction ("interface is not allowed", Def);
15534 if not Is_Interface (Parent_Type) then
15535 Diagnose_Interface (Indic, Parent_Type);
15538 Parent_Node := Parent (Base_Type (Parent_Type));
15539 Iface_Def := Type_Definition (Parent_Node);
15541 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
15542 -- other limited interfaces.
15544 if Limited_Present (Def) then
15545 if Limited_Present (Iface_Def) then
15548 elsif Protected_Present (Iface_Def) then
15550 ("descendant of& must be declared"
15551 & " as a protected interface",
15554 elsif Synchronized_Present (Iface_Def) then
15556 ("descendant of& must be declared"
15557 & " as a synchronized interface",
15560 elsif Task_Present (Iface_Def) then
15562 ("descendant of& must be declared as a task interface",
15567 ("(Ada 2005) limited interface cannot "
15568 & "inherit from non-limited interface", Indic);
15571 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
15572 -- from non-limited or limited interfaces.
15574 elsif not Protected_Present (Def)
15575 and then not Synchronized_Present (Def)
15576 and then not Task_Present (Def)
15578 if Limited_Present (Iface_Def) then
15581 elsif Protected_Present (Iface_Def) then
15583 ("descendant of& must be declared"
15584 & " as a protected interface",
15587 elsif Synchronized_Present (Iface_Def) then
15589 ("descendant of& must be declared"
15590 & " as a synchronized interface",
15593 elsif Task_Present (Iface_Def) then
15595 ("descendant of& must be declared as a task interface",
15604 if Is_Tagged_Type (Parent_Type)
15605 and then Is_Concurrent_Type (Parent_Type)
15606 and then not Is_Interface (Parent_Type)
15609 ("parent type of a record extension cannot be "
15610 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
15611 Set_Etype (T, Any_Type);
15615 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
15618 if Is_Tagged_Type (Parent_Type)
15619 and then Is_Non_Empty_List (Interface_List (Def))
15626 Intf := First (Interface_List (Def));
15627 while Present (Intf) loop
15628 T := Find_Type_Of_Subtype_Indic (Intf);
15630 if not Is_Interface (T) then
15631 Diagnose_Interface (Intf, T);
15633 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
15634 -- a limited type from having a nonlimited progenitor.
15636 elsif (Limited_Present (Def)
15637 or else (not Is_Interface (Parent_Type)
15638 and then Is_Limited_Type (Parent_Type)))
15639 and then not Is_Limited_Interface (T)
15642 ("progenitor interface& of limited type must be limited",
15651 if Parent_Type = Any_Type
15652 or else Etype (Parent_Type) = Any_Type
15653 or else (Is_Class_Wide_Type (Parent_Type)
15654 and then Etype (Parent_Type) = T)
15656 -- If Parent_Type is undefined or illegal, make new type into a
15657 -- subtype of Any_Type, and set a few attributes to prevent cascaded
15658 -- errors. If this is a self-definition, emit error now.
15660 if T = Parent_Type or else T = Etype (Parent_Type) then
15661 Error_Msg_N ("type cannot be used in its own definition", Indic);
15664 Set_Ekind (T, Ekind (Parent_Type));
15665 Set_Etype (T, Any_Type);
15666 Set_Scalar_Range (T, Scalar_Range (Any_Type));
15668 if Is_Tagged_Type (T)
15669 and then Is_Record_Type (T)
15671 Set_Direct_Primitive_Operations (T, New_Elmt_List);
15677 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
15678 -- an interface is special because the list of interfaces in the full
15679 -- view can be given in any order. For example:
15681 -- type A is interface;
15682 -- type B is interface and A;
15683 -- type D is new B with private;
15685 -- type D is new A and B with null record; -- 1 --
15687 -- In this case we perform the following transformation of -1-:
15689 -- type D is new B and A with null record;
15691 -- If the parent of the full-view covers the parent of the partial-view
15692 -- we have two possible cases:
15694 -- 1) They have the same parent
15695 -- 2) The parent of the full-view implements some further interfaces
15697 -- In both cases we do not need to perform the transformation. In the
15698 -- first case the source program is correct and the transformation is
15699 -- not needed; in the second case the source program does not fulfill
15700 -- the no-hidden interfaces rule (AI-396) and the error will be reported
15703 -- This transformation not only simplifies the rest of the analysis of
15704 -- this type declaration but also simplifies the correct generation of
15705 -- the object layout to the expander.
15707 if In_Private_Part (Current_Scope)
15708 and then Is_Interface (Parent_Type)
15712 Partial_View : Entity_Id;
15713 Partial_View_Parent : Entity_Id;
15714 New_Iface : Node_Id;
15717 -- Look for the associated private type declaration
15719 Partial_View := First_Entity (Current_Scope);
15721 exit when No (Partial_View)
15722 or else (Has_Private_Declaration (Partial_View)
15723 and then Full_View (Partial_View) = T);
15725 Next_Entity (Partial_View);
15728 -- If the partial view was not found then the source code has
15729 -- errors and the transformation is not needed.
15731 if Present (Partial_View) then
15732 Partial_View_Parent := Etype (Partial_View);
15734 -- If the parent of the full-view covers the parent of the
15735 -- partial-view we have nothing else to do.
15737 if Interface_Present_In_Ancestor
15738 (Parent_Type, Partial_View_Parent)
15742 -- Traverse the list of interfaces of the full-view to look
15743 -- for the parent of the partial-view and perform the tree
15747 Iface := First (Interface_List (Def));
15748 while Present (Iface) loop
15749 if Etype (Iface) = Etype (Partial_View) then
15750 Rewrite (Subtype_Indication (Def),
15751 New_Copy (Subtype_Indication
15752 (Parent (Partial_View))));
15755 Make_Identifier (Sloc (N), Chars (Parent_Type));
15756 Append (New_Iface, Interface_List (Def));
15758 -- Analyze the transformed code
15760 Derived_Type_Declaration (T, N, Is_Completion);
15771 -- Only composite types other than array types are allowed to have
15774 if Present (Discriminant_Specifications (N)) then
15775 if (Is_Elementary_Type (Parent_Type)
15777 Is_Array_Type (Parent_Type))
15778 and then not Error_Posted (N)
15781 ("elementary or array type cannot have discriminants",
15782 Defining_Identifier (First (Discriminant_Specifications (N))));
15783 Set_Has_Discriminants (T, False);
15785 -- The type is allowed to have discriminants
15788 Check_SPARK_05_Restriction ("discriminant type is not allowed", N);
15792 -- In Ada 83, a derived type defined in a package specification cannot
15793 -- be used for further derivation until the end of its visible part.
15794 -- Note that derivation in the private part of the package is allowed.
15796 if Ada_Version = Ada_83
15797 and then Is_Derived_Type (Parent_Type)
15798 and then In_Visible_Part (Scope (Parent_Type))
15800 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
15802 ("(Ada 83): premature use of type for derivation", Indic);
15806 -- Check for early use of incomplete or private type
15808 if Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
15809 Error_Msg_N ("premature derivation of incomplete type", Indic);
15812 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
15813 and then not Comes_From_Generic (Parent_Type))
15814 or else Has_Private_Component (Parent_Type)
15816 -- The ancestor type of a formal type can be incomplete, in which
15817 -- case only the operations of the partial view are available in the
15818 -- generic. Subsequent checks may be required when the full view is
15819 -- analyzed to verify that a derivation from a tagged type has an
15822 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
15825 elsif No (Underlying_Type (Parent_Type))
15826 or else Has_Private_Component (Parent_Type)
15829 ("premature derivation of derived or private type", Indic);
15831 -- Flag the type itself as being in error, this prevents some
15832 -- nasty problems with subsequent uses of the malformed type.
15834 Set_Error_Posted (T);
15836 -- Check that within the immediate scope of an untagged partial
15837 -- view it's illegal to derive from the partial view if the
15838 -- full view is tagged. (7.3(7))
15840 -- We verify that the Parent_Type is a partial view by checking
15841 -- that it is not a Full_Type_Declaration (i.e. a private type or
15842 -- private extension declaration), to distinguish a partial view
15843 -- from a derivation from a private type which also appears as
15844 -- E_Private_Type. If the parent base type is not declared in an
15845 -- enclosing scope there is no need to check.
15847 elsif Present (Full_View (Parent_Type))
15848 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
15849 and then not Is_Tagged_Type (Parent_Type)
15850 and then Is_Tagged_Type (Full_View (Parent_Type))
15851 and then In_Open_Scopes (Scope (Base_Type (Parent_Type)))
15854 ("premature derivation from type with tagged full view",
15859 -- Check that form of derivation is appropriate
15861 Taggd := Is_Tagged_Type (Parent_Type);
15863 -- Set the parent type to the class-wide type's specific type in this
15864 -- case to prevent cascading errors
15866 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
15867 Error_Msg_N ("parent type must not be a class-wide type", Indic);
15868 Set_Etype (T, Etype (Parent_Type));
15872 if Present (Extension) and then not Taggd then
15874 ("type derived from untagged type cannot have extension", Indic);
15876 elsif No (Extension) and then Taggd then
15878 -- If this declaration is within a private part (or body) of a
15879 -- generic instantiation then the derivation is allowed (the parent
15880 -- type can only appear tagged in this case if it's a generic actual
15881 -- type, since it would otherwise have been rejected in the analysis
15882 -- of the generic template).
15884 if not Is_Generic_Actual_Type (Parent_Type)
15885 or else In_Visible_Part (Scope (Parent_Type))
15887 if Is_Class_Wide_Type (Parent_Type) then
15889 ("parent type must not be a class-wide type", Indic);
15891 -- Use specific type to prevent cascaded errors.
15893 Parent_Type := Etype (Parent_Type);
15897 ("type derived from tagged type must have extension", Indic);
15902 -- AI-443: Synchronized formal derived types require a private
15903 -- extension. There is no point in checking the ancestor type or
15904 -- the progenitors since the construct is wrong to begin with.
15906 if Ada_Version >= Ada_2005
15907 and then Is_Generic_Type (T)
15908 and then Present (Original_Node (N))
15911 Decl : constant Node_Id := Original_Node (N);
15914 if Nkind (Decl) = N_Formal_Type_Declaration
15915 and then Nkind (Formal_Type_Definition (Decl)) =
15916 N_Formal_Derived_Type_Definition
15917 and then Synchronized_Present (Formal_Type_Definition (Decl))
15918 and then No (Extension)
15920 -- Avoid emitting a duplicate error message
15922 and then not Error_Posted (Indic)
15925 ("synchronized derived type must have extension", N);
15930 if Null_Exclusion_Present (Def)
15931 and then not Is_Access_Type (Parent_Type)
15933 Error_Msg_N ("null exclusion can only apply to an access type", N);
15936 -- Avoid deriving parent primitives of underlying record views
15938 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
15939 Derive_Subps => not Is_Underlying_Record_View (T));
15941 -- AI-419: The parent type of an explicitly limited derived type must
15942 -- be a limited type or a limited interface.
15944 if Limited_Present (Def) then
15945 Set_Is_Limited_Record (T);
15947 if Is_Interface (T) then
15948 Set_Is_Limited_Interface (T);
15951 if not Is_Limited_Type (Parent_Type)
15953 (not Is_Interface (Parent_Type)
15954 or else not Is_Limited_Interface (Parent_Type))
15956 -- AI05-0096: a derivation in the private part of an instance is
15957 -- legal if the generic formal is untagged limited, and the actual
15960 if Is_Generic_Actual_Type (Parent_Type)
15961 and then In_Private_Part (Current_Scope)
15964 (Generic_Parent_Type (Parent (Parent_Type)))
15970 ("parent type& of limited type must be limited",
15976 -- In SPARK, there are no derived type definitions other than type
15977 -- extensions of tagged record types.
15979 if No (Extension) then
15980 Check_SPARK_05_Restriction
15981 ("derived type is not allowed", Original_Node (N));
15983 end Derived_Type_Declaration;
15985 ------------------------
15986 -- Diagnose_Interface --
15987 ------------------------
15989 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
15991 if not Is_Interface (E) and then E /= Any_Type then
15992 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
15994 end Diagnose_Interface;
15996 ----------------------------------
15997 -- Enumeration_Type_Declaration --
15998 ----------------------------------
16000 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
16007 -- Create identifier node representing lower bound
16009 B_Node := New_Node (N_Identifier, Sloc (Def));
16010 L := First (Literals (Def));
16011 Set_Chars (B_Node, Chars (L));
16012 Set_Entity (B_Node, L);
16013 Set_Etype (B_Node, T);
16014 Set_Is_Static_Expression (B_Node, True);
16016 R_Node := New_Node (N_Range, Sloc (Def));
16017 Set_Low_Bound (R_Node, B_Node);
16019 Set_Ekind (T, E_Enumeration_Type);
16020 Set_First_Literal (T, L);
16022 Set_Is_Constrained (T);
16026 -- Loop through literals of enumeration type setting pos and rep values
16027 -- except that if the Ekind is already set, then it means the literal
16028 -- was already constructed (case of a derived type declaration and we
16029 -- should not disturb the Pos and Rep values.
16031 while Present (L) loop
16032 if Ekind (L) /= E_Enumeration_Literal then
16033 Set_Ekind (L, E_Enumeration_Literal);
16034 Set_Enumeration_Pos (L, Ev);
16035 Set_Enumeration_Rep (L, Ev);
16036 Set_Is_Known_Valid (L, True);
16040 New_Overloaded_Entity (L);
16041 Generate_Definition (L);
16042 Set_Convention (L, Convention_Intrinsic);
16044 -- Case of character literal
16046 if Nkind (L) = N_Defining_Character_Literal then
16047 Set_Is_Character_Type (T, True);
16049 -- Check violation of No_Wide_Characters
16051 if Restriction_Check_Required (No_Wide_Characters) then
16052 Get_Name_String (Chars (L));
16054 if Name_Len >= 3 and then Name_Buffer (1 .. 2) = "QW" then
16055 Check_Restriction (No_Wide_Characters, L);
16064 -- Now create a node representing upper bound
16066 B_Node := New_Node (N_Identifier, Sloc (Def));
16067 Set_Chars (B_Node, Chars (Last (Literals (Def))));
16068 Set_Entity (B_Node, Last (Literals (Def)));
16069 Set_Etype (B_Node, T);
16070 Set_Is_Static_Expression (B_Node, True);
16072 Set_High_Bound (R_Node, B_Node);
16074 -- Initialize various fields of the type. Some of this information
16075 -- may be overwritten later through rep.clauses.
16077 Set_Scalar_Range (T, R_Node);
16078 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
16079 Set_Enum_Esize (T);
16080 Set_Enum_Pos_To_Rep (T, Empty);
16082 -- Set Discard_Names if configuration pragma set, or if there is
16083 -- a parameterless pragma in the current declarative region
16085 if Global_Discard_Names or else Discard_Names (Scope (T)) then
16086 Set_Discard_Names (T);
16089 -- Process end label if there is one
16091 if Present (Def) then
16092 Process_End_Label (Def, 'e', T);
16094 end Enumeration_Type_Declaration;
16096 ---------------------------------
16097 -- Expand_To_Stored_Constraint --
16098 ---------------------------------
16100 function Expand_To_Stored_Constraint
16102 Constraint : Elist_Id) return Elist_Id
16104 Explicitly_Discriminated_Type : Entity_Id;
16105 Expansion : Elist_Id;
16106 Discriminant : Entity_Id;
16108 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
16109 -- Find the nearest type that actually specifies discriminants
16111 ---------------------------------
16112 -- Type_With_Explicit_Discrims --
16113 ---------------------------------
16115 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
16116 Typ : constant E := Base_Type (Id);
16119 if Ekind (Typ) in Incomplete_Or_Private_Kind then
16120 if Present (Full_View (Typ)) then
16121 return Type_With_Explicit_Discrims (Full_View (Typ));
16125 if Has_Discriminants (Typ) then
16130 if Etype (Typ) = Typ then
16132 elsif Has_Discriminants (Typ) then
16135 return Type_With_Explicit_Discrims (Etype (Typ));
16138 end Type_With_Explicit_Discrims;
16140 -- Start of processing for Expand_To_Stored_Constraint
16143 if No (Constraint) or else Is_Empty_Elmt_List (Constraint) then
16147 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
16149 if No (Explicitly_Discriminated_Type) then
16153 Expansion := New_Elmt_List;
16156 First_Stored_Discriminant (Explicitly_Discriminated_Type);
16157 while Present (Discriminant) loop
16159 (Get_Discriminant_Value
16160 (Discriminant, Explicitly_Discriminated_Type, Constraint),
16162 Next_Stored_Discriminant (Discriminant);
16166 end Expand_To_Stored_Constraint;
16168 ---------------------------
16169 -- Find_Hidden_Interface --
16170 ---------------------------
16172 function Find_Hidden_Interface
16174 Dest : Elist_Id) return Entity_Id
16177 Iface_Elmt : Elmt_Id;
16180 if Present (Src) and then Present (Dest) then
16181 Iface_Elmt := First_Elmt (Src);
16182 while Present (Iface_Elmt) loop
16183 Iface := Node (Iface_Elmt);
16185 if Is_Interface (Iface)
16186 and then not Contain_Interface (Iface, Dest)
16191 Next_Elmt (Iface_Elmt);
16196 end Find_Hidden_Interface;
16198 --------------------
16199 -- Find_Type_Name --
16200 --------------------
16202 function Find_Type_Name (N : Node_Id) return Entity_Id is
16203 Id : constant Entity_Id := Defining_Identifier (N);
16205 New_Id : Entity_Id;
16206 Prev_Par : Node_Id;
16208 procedure Check_Duplicate_Aspects;
16209 -- Check that aspects specified in a completion have not been specified
16210 -- already in the partial view. Type_Invariant and others can be
16211 -- specified on either view but never on both.
16213 procedure Tag_Mismatch;
16214 -- Diagnose a tagged partial view whose full view is untagged.
16215 -- We post the message on the full view, with a reference to
16216 -- the previous partial view. The partial view can be private
16217 -- or incomplete, and these are handled in a different manner,
16218 -- so we determine the position of the error message from the
16219 -- respective slocs of both.
16221 -----------------------------
16222 -- Check_Duplicate_Aspects --
16223 -----------------------------
16224 procedure Check_Duplicate_Aspects is
16225 Prev_Aspects : constant List_Id := Aspect_Specifications (Prev_Par);
16226 Full_Aspects : constant List_Id := Aspect_Specifications (N);
16227 F_Spec, P_Spec : Node_Id;
16230 if Present (Prev_Aspects) and then Present (Full_Aspects) then
16231 F_Spec := First (Full_Aspects);
16232 while Present (F_Spec) loop
16233 P_Spec := First (Prev_Aspects);
16234 while Present (P_Spec) loop
16235 if Chars (Identifier (P_Spec)) = Chars (Identifier (F_Spec))
16238 ("aspect already specified in private declaration",
16250 end Check_Duplicate_Aspects;
16256 procedure Tag_Mismatch is
16258 if Sloc (Prev) < Sloc (Id) then
16259 if Ada_Version >= Ada_2012
16260 and then Nkind (N) = N_Private_Type_Declaration
16263 ("declaration of private } must be a tagged type ", Id, Prev);
16266 ("full declaration of } must be a tagged type ", Id, Prev);
16270 if Ada_Version >= Ada_2012
16271 and then Nkind (N) = N_Private_Type_Declaration
16274 ("declaration of private } must be a tagged type ", Prev, Id);
16277 ("full declaration of } must be a tagged type ", Prev, Id);
16282 -- Start of processing for Find_Type_Name
16285 -- Find incomplete declaration, if one was given
16287 Prev := Current_Entity_In_Scope (Id);
16289 -- New type declaration
16295 -- Previous declaration exists
16298 Prev_Par := Parent (Prev);
16300 -- Error if not incomplete/private case except if previous
16301 -- declaration is implicit, etc. Enter_Name will emit error if
16304 if not Is_Incomplete_Or_Private_Type (Prev) then
16308 -- Check invalid completion of private or incomplete type
16310 elsif not Nkind_In (N, N_Full_Type_Declaration,
16311 N_Task_Type_Declaration,
16312 N_Protected_Type_Declaration)
16314 (Ada_Version < Ada_2012
16315 or else not Is_Incomplete_Type (Prev)
16316 or else not Nkind_In (N, N_Private_Type_Declaration,
16317 N_Private_Extension_Declaration))
16319 -- Completion must be a full type declarations (RM 7.3(4))
16321 Error_Msg_Sloc := Sloc (Prev);
16322 Error_Msg_NE ("invalid completion of }", Id, Prev);
16324 -- Set scope of Id to avoid cascaded errors. Entity is never
16325 -- examined again, except when saving globals in generics.
16327 Set_Scope (Id, Current_Scope);
16330 -- If this is a repeated incomplete declaration, no further
16331 -- checks are possible.
16333 if Nkind (N) = N_Incomplete_Type_Declaration then
16337 -- Case of full declaration of incomplete type
16339 elsif Ekind (Prev) = E_Incomplete_Type
16340 and then (Ada_Version < Ada_2012
16341 or else No (Full_View (Prev))
16342 or else not Is_Private_Type (Full_View (Prev)))
16344 -- Indicate that the incomplete declaration has a matching full
16345 -- declaration. The defining occurrence of the incomplete
16346 -- declaration remains the visible one, and the procedure
16347 -- Get_Full_View dereferences it whenever the type is used.
16349 if Present (Full_View (Prev)) then
16350 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
16353 Set_Full_View (Prev, Id);
16354 Append_Entity (Id, Current_Scope);
16355 Set_Is_Public (Id, Is_Public (Prev));
16356 Set_Is_Internal (Id);
16359 -- If the incomplete view is tagged, a class_wide type has been
16360 -- created already. Use it for the private type as well, in order
16361 -- to prevent multiple incompatible class-wide types that may be
16362 -- created for self-referential anonymous access components.
16364 if Is_Tagged_Type (Prev)
16365 and then Present (Class_Wide_Type (Prev))
16367 Set_Ekind (Id, Ekind (Prev)); -- will be reset later
16368 Set_Class_Wide_Type (Id, Class_Wide_Type (Prev));
16370 -- The type of the classwide type is the current Id. Previously
16371 -- this was not done for private declarations because of order-
16372 -- of elaboration issues in the back-end, but gigi now handles
16375 Set_Etype (Class_Wide_Type (Id), Id);
16378 -- Case of full declaration of private type
16381 -- If the private type was a completion of an incomplete type then
16382 -- update Prev to reference the private type
16384 if Ada_Version >= Ada_2012
16385 and then Ekind (Prev) = E_Incomplete_Type
16386 and then Present (Full_View (Prev))
16387 and then Is_Private_Type (Full_View (Prev))
16389 Prev := Full_View (Prev);
16390 Prev_Par := Parent (Prev);
16393 if Nkind (N) = N_Full_Type_Declaration
16395 (Type_Definition (N), N_Record_Definition,
16396 N_Derived_Type_Definition)
16397 and then Interface_Present (Type_Definition (N))
16400 ("completion of private type cannot be an interface", N);
16403 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
16404 if Etype (Prev) /= Prev then
16406 -- Prev is a private subtype or a derived type, and needs
16409 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
16412 elsif Ekind (Prev) = E_Private_Type
16413 and then Nkind_In (N, N_Task_Type_Declaration,
16414 N_Protected_Type_Declaration)
16417 ("completion of nonlimited type cannot be limited", N);
16419 elsif Ekind (Prev) = E_Record_Type_With_Private
16420 and then Nkind_In (N, N_Task_Type_Declaration,
16421 N_Protected_Type_Declaration)
16423 if not Is_Limited_Record (Prev) then
16425 ("completion of nonlimited type cannot be limited", N);
16427 elsif No (Interface_List (N)) then
16429 ("completion of tagged private type must be tagged",
16434 -- Ada 2005 (AI-251): Private extension declaration of a task
16435 -- type or a protected type. This case arises when covering
16436 -- interface types.
16438 elsif Nkind_In (N, N_Task_Type_Declaration,
16439 N_Protected_Type_Declaration)
16443 elsif Nkind (N) /= N_Full_Type_Declaration
16444 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
16447 ("full view of private extension must be an extension", N);
16449 elsif not (Abstract_Present (Parent (Prev)))
16450 and then Abstract_Present (Type_Definition (N))
16453 ("full view of non-abstract extension cannot be abstract", N);
16456 if not In_Private_Part (Current_Scope) then
16458 ("declaration of full view must appear in private part", N);
16461 if Ada_Version >= Ada_2012 then
16462 Check_Duplicate_Aspects;
16465 Copy_And_Swap (Prev, Id);
16466 Set_Has_Private_Declaration (Prev);
16467 Set_Has_Private_Declaration (Id);
16469 -- Preserve aspect and iterator flags that may have been set on
16470 -- the partial view.
16472 Set_Has_Delayed_Aspects (Prev, Has_Delayed_Aspects (Id));
16473 Set_Has_Implicit_Dereference (Prev, Has_Implicit_Dereference (Id));
16475 -- If no error, propagate freeze_node from private to full view.
16476 -- It may have been generated for an early operational item.
16478 if Present (Freeze_Node (Id))
16479 and then Serious_Errors_Detected = 0
16480 and then No (Full_View (Id))
16482 Set_Freeze_Node (Prev, Freeze_Node (Id));
16483 Set_Freeze_Node (Id, Empty);
16484 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
16487 Set_Full_View (Id, Prev);
16491 -- Verify that full declaration conforms to partial one
16493 if Is_Incomplete_Or_Private_Type (Prev)
16494 and then Present (Discriminant_Specifications (Prev_Par))
16496 if Present (Discriminant_Specifications (N)) then
16497 if Ekind (Prev) = E_Incomplete_Type then
16498 Check_Discriminant_Conformance (N, Prev, Prev);
16500 Check_Discriminant_Conformance (N, Prev, Id);
16505 ("missing discriminants in full type declaration", N);
16507 -- To avoid cascaded errors on subsequent use, share the
16508 -- discriminants of the partial view.
16510 Set_Discriminant_Specifications (N,
16511 Discriminant_Specifications (Prev_Par));
16515 -- A prior untagged partial view can have an associated class-wide
16516 -- type due to use of the class attribute, and in this case the full
16517 -- type must also be tagged. This Ada 95 usage is deprecated in favor
16518 -- of incomplete tagged declarations, but we check for it.
16521 and then (Is_Tagged_Type (Prev)
16522 or else Present (Class_Wide_Type (Prev)))
16524 -- Ada 2012 (AI05-0162): A private type may be the completion of
16525 -- an incomplete type.
16527 if Ada_Version >= Ada_2012
16528 and then Is_Incomplete_Type (Prev)
16529 and then Nkind_In (N, N_Private_Type_Declaration,
16530 N_Private_Extension_Declaration)
16532 -- No need to check private extensions since they are tagged
16534 if Nkind (N) = N_Private_Type_Declaration
16535 and then not Tagged_Present (N)
16540 -- The full declaration is either a tagged type (including
16541 -- a synchronized type that implements interfaces) or a
16542 -- type extension, otherwise this is an error.
16544 elsif Nkind_In (N, N_Task_Type_Declaration,
16545 N_Protected_Type_Declaration)
16547 if No (Interface_List (N)) and then not Error_Posted (N) then
16551 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
16553 -- Indicate that the previous declaration (tagged incomplete
16554 -- or private declaration) requires the same on the full one.
16556 if not Tagged_Present (Type_Definition (N)) then
16558 Set_Is_Tagged_Type (Id);
16561 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
16562 if No (Record_Extension_Part (Type_Definition (N))) then
16564 ("full declaration of } must be a record extension",
16567 -- Set some attributes to produce a usable full view
16569 Set_Is_Tagged_Type (Id);
16578 and then Nkind (Parent (Prev)) = N_Incomplete_Type_Declaration
16579 and then Present (Premature_Use (Parent (Prev)))
16581 Error_Msg_Sloc := Sloc (N);
16583 ("\full declaration #", Premature_Use (Parent (Prev)));
16588 end Find_Type_Name;
16590 -------------------------
16591 -- Find_Type_Of_Object --
16592 -------------------------
16594 function Find_Type_Of_Object
16595 (Obj_Def : Node_Id;
16596 Related_Nod : Node_Id) return Entity_Id
16598 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
16599 P : Node_Id := Parent (Obj_Def);
16604 -- If the parent is a component_definition node we climb to the
16605 -- component_declaration node
16607 if Nkind (P) = N_Component_Definition then
16611 -- Case of an anonymous array subtype
16613 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
16614 N_Unconstrained_Array_Definition)
16617 Array_Type_Declaration (T, Obj_Def);
16619 -- Create an explicit subtype whenever possible
16621 elsif Nkind (P) /= N_Component_Declaration
16622 and then Def_Kind = N_Subtype_Indication
16624 -- Base name of subtype on object name, which will be unique in
16625 -- the current scope.
16627 -- If this is a duplicate declaration, return base type, to avoid
16628 -- generating duplicate anonymous types.
16630 if Error_Posted (P) then
16631 Analyze (Subtype_Mark (Obj_Def));
16632 return Entity (Subtype_Mark (Obj_Def));
16637 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
16639 T := Make_Defining_Identifier (Sloc (P), Nam);
16641 Insert_Action (Obj_Def,
16642 Make_Subtype_Declaration (Sloc (P),
16643 Defining_Identifier => T,
16644 Subtype_Indication => Relocate_Node (Obj_Def)));
16646 -- This subtype may need freezing, and this will not be done
16647 -- automatically if the object declaration is not in declarative
16648 -- part. Since this is an object declaration, the type cannot always
16649 -- be frozen here. Deferred constants do not freeze their type
16650 -- (which often enough will be private).
16652 if Nkind (P) = N_Object_Declaration
16653 and then Constant_Present (P)
16654 and then No (Expression (P))
16658 -- Here we freeze the base type of object type to catch premature use
16659 -- of discriminated private type without a full view.
16662 Insert_Actions (Obj_Def, Freeze_Entity (Base_Type (T), P));
16665 -- Ada 2005 AI-406: the object definition in an object declaration
16666 -- can be an access definition.
16668 elsif Def_Kind = N_Access_Definition then
16669 T := Access_Definition (Related_Nod, Obj_Def);
16671 Set_Is_Local_Anonymous_Access
16673 V => (Ada_Version < Ada_2012)
16674 or else (Nkind (P) /= N_Object_Declaration)
16675 or else Is_Library_Level_Entity (Defining_Identifier (P)));
16677 -- Otherwise, the object definition is just a subtype_mark
16680 T := Process_Subtype (Obj_Def, Related_Nod);
16682 -- If expansion is disabled an object definition that is an aggregate
16683 -- will not get expanded and may lead to scoping problems in the back
16684 -- end, if the object is referenced in an inner scope. In that case
16685 -- create an itype reference for the object definition now. This
16686 -- may be redundant in some cases, but harmless.
16689 and then Nkind (Related_Nod) = N_Object_Declaration
16692 Build_Itype_Reference (T, Related_Nod);
16697 end Find_Type_Of_Object;
16699 --------------------------------
16700 -- Find_Type_Of_Subtype_Indic --
16701 --------------------------------
16703 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
16707 -- Case of subtype mark with a constraint
16709 if Nkind (S) = N_Subtype_Indication then
16710 Find_Type (Subtype_Mark (S));
16711 Typ := Entity (Subtype_Mark (S));
16714 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
16717 ("incorrect constraint for this kind of type", Constraint (S));
16718 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
16721 -- Otherwise we have a subtype mark without a constraint
16723 elsif Error_Posted (S) then
16724 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
16732 -- Check No_Wide_Characters restriction
16734 Check_Wide_Character_Restriction (Typ, S);
16737 end Find_Type_Of_Subtype_Indic;
16739 -------------------------------------
16740 -- Floating_Point_Type_Declaration --
16741 -------------------------------------
16743 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
16744 Digs : constant Node_Id := Digits_Expression (Def);
16745 Max_Digs_Val : constant Uint := Digits_Value (Standard_Long_Long_Float);
16747 Base_Typ : Entity_Id;
16748 Implicit_Base : Entity_Id;
16751 function Can_Derive_From (E : Entity_Id) return Boolean;
16752 -- Find if given digits value, and possibly a specified range, allows
16753 -- derivation from specified type
16755 function Find_Base_Type return Entity_Id;
16756 -- Find a predefined base type that Def can derive from, or generate
16757 -- an error and substitute Long_Long_Float if none exists.
16759 ---------------------
16760 -- Can_Derive_From --
16761 ---------------------
16763 function Can_Derive_From (E : Entity_Id) return Boolean is
16764 Spec : constant Entity_Id := Real_Range_Specification (Def);
16767 -- Check specified "digits" constraint
16769 if Digs_Val > Digits_Value (E) then
16773 -- Check for matching range, if specified
16775 if Present (Spec) then
16776 if Expr_Value_R (Type_Low_Bound (E)) >
16777 Expr_Value_R (Low_Bound (Spec))
16782 if Expr_Value_R (Type_High_Bound (E)) <
16783 Expr_Value_R (High_Bound (Spec))
16790 end Can_Derive_From;
16792 --------------------
16793 -- Find_Base_Type --
16794 --------------------
16796 function Find_Base_Type return Entity_Id is
16797 Choice : Elmt_Id := First_Elmt (Predefined_Float_Types);
16800 -- Iterate over the predefined types in order, returning the first
16801 -- one that Def can derive from.
16803 while Present (Choice) loop
16804 if Can_Derive_From (Node (Choice)) then
16805 return Node (Choice);
16808 Next_Elmt (Choice);
16811 -- If we can't derive from any existing type, use Long_Long_Float
16812 -- and give appropriate message explaining the problem.
16814 if Digs_Val > Max_Digs_Val then
16815 -- It might be the case that there is a type with the requested
16816 -- range, just not the combination of digits and range.
16819 ("no predefined type has requested range and precision",
16820 Real_Range_Specification (Def));
16824 ("range too large for any predefined type",
16825 Real_Range_Specification (Def));
16828 return Standard_Long_Long_Float;
16829 end Find_Base_Type;
16831 -- Start of processing for Floating_Point_Type_Declaration
16834 Check_Restriction (No_Floating_Point, Def);
16836 -- Create an implicit base type
16839 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
16841 -- Analyze and verify digits value
16843 Analyze_And_Resolve (Digs, Any_Integer);
16844 Check_Digits_Expression (Digs);
16845 Digs_Val := Expr_Value (Digs);
16847 -- Process possible range spec and find correct type to derive from
16849 Process_Real_Range_Specification (Def);
16851 -- Check that requested number of digits is not too high.
16853 if Digs_Val > Max_Digs_Val then
16855 -- The check for Max_Base_Digits may be somewhat expensive, as it
16856 -- requires reading System, so only do it when necessary.
16859 Max_Base_Digits : constant Uint :=
16862 (Parent (RTE (RE_Max_Base_Digits))));
16865 if Digs_Val > Max_Base_Digits then
16866 Error_Msg_Uint_1 := Max_Base_Digits;
16867 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
16869 elsif No (Real_Range_Specification (Def)) then
16870 Error_Msg_Uint_1 := Max_Digs_Val;
16871 Error_Msg_N ("types with more than ^ digits need range spec "
16872 & "(RM 3.5.7(6))", Digs);
16877 -- Find a suitable type to derive from or complain and use a substitute
16879 Base_Typ := Find_Base_Type;
16881 -- If there are bounds given in the declaration use them as the bounds
16882 -- of the type, otherwise use the bounds of the predefined base type
16883 -- that was chosen based on the Digits value.
16885 if Present (Real_Range_Specification (Def)) then
16886 Set_Scalar_Range (T, Real_Range_Specification (Def));
16887 Set_Is_Constrained (T);
16889 -- The bounds of this range must be converted to machine numbers
16890 -- in accordance with RM 4.9(38).
16892 Bound := Type_Low_Bound (T);
16894 if Nkind (Bound) = N_Real_Literal then
16896 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
16897 Set_Is_Machine_Number (Bound);
16900 Bound := Type_High_Bound (T);
16902 if Nkind (Bound) = N_Real_Literal then
16904 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
16905 Set_Is_Machine_Number (Bound);
16909 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
16912 -- Complete definition of implicit base and declared first subtype. The
16913 -- inheritance of the rep item chain ensures that SPARK-related pragmas
16914 -- are not clobbered when the floating point type acts as a full view of
16917 Set_Etype (Implicit_Base, Base_Typ);
16918 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
16919 Set_Size_Info (Implicit_Base, Base_Typ);
16920 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
16921 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
16922 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
16923 Set_Float_Rep (Implicit_Base, Float_Rep (Base_Typ));
16925 Set_Ekind (T, E_Floating_Point_Subtype);
16926 Set_Etype (T, Implicit_Base);
16927 Set_Size_Info (T, Implicit_Base);
16928 Set_RM_Size (T, RM_Size (Implicit_Base));
16929 Inherit_Rep_Item_Chain (T, Implicit_Base);
16930 Set_Digits_Value (T, Digs_Val);
16931 end Floating_Point_Type_Declaration;
16933 ----------------------------
16934 -- Get_Discriminant_Value --
16935 ----------------------------
16937 -- This is the situation:
16939 -- There is a non-derived type
16941 -- type T0 (Dx, Dy, Dz...)
16943 -- There are zero or more levels of derivation, with each derivation
16944 -- either purely inheriting the discriminants, or defining its own.
16946 -- type Ti is new Ti-1
16948 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
16950 -- subtype Ti is ...
16952 -- The subtype issue is avoided by the use of Original_Record_Component,
16953 -- and the fact that derived subtypes also derive the constraints.
16955 -- This chain leads back from
16957 -- Typ_For_Constraint
16959 -- Typ_For_Constraint has discriminants, and the value for each
16960 -- discriminant is given by its corresponding Elmt of Constraints.
16962 -- Discriminant is some discriminant in this hierarchy
16964 -- We need to return its value
16966 -- We do this by recursively searching each level, and looking for
16967 -- Discriminant. Once we get to the bottom, we start backing up
16968 -- returning the value for it which may in turn be a discriminant
16969 -- further up, so on the backup we continue the substitution.
16971 function Get_Discriminant_Value
16972 (Discriminant : Entity_Id;
16973 Typ_For_Constraint : Entity_Id;
16974 Constraint : Elist_Id) return Node_Id
16976 function Root_Corresponding_Discriminant
16977 (Discr : Entity_Id) return Entity_Id;
16978 -- Given a discriminant, traverse the chain of inherited discriminants
16979 -- and return the topmost discriminant.
16981 function Search_Derivation_Levels
16983 Discrim_Values : Elist_Id;
16984 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
16985 -- This is the routine that performs the recursive search of levels
16986 -- as described above.
16988 -------------------------------------
16989 -- Root_Corresponding_Discriminant --
16990 -------------------------------------
16992 function Root_Corresponding_Discriminant
16993 (Discr : Entity_Id) return Entity_Id
16999 while Present (Corresponding_Discriminant (D)) loop
17000 D := Corresponding_Discriminant (D);
17004 end Root_Corresponding_Discriminant;
17006 ------------------------------
17007 -- Search_Derivation_Levels --
17008 ------------------------------
17010 function Search_Derivation_Levels
17012 Discrim_Values : Elist_Id;
17013 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
17017 Result : Node_Or_Entity_Id;
17018 Result_Entity : Node_Id;
17021 -- If inappropriate type, return Error, this happens only in
17022 -- cascaded error situations, and we want to avoid a blow up.
17024 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
17028 -- Look deeper if possible. Use Stored_Constraints only for
17029 -- untagged types. For tagged types use the given constraint.
17030 -- This asymmetry needs explanation???
17032 if not Stored_Discrim_Values
17033 and then Present (Stored_Constraint (Ti))
17034 and then not Is_Tagged_Type (Ti)
17037 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
17040 Td : constant Entity_Id := Etype (Ti);
17044 Result := Discriminant;
17047 if Present (Stored_Constraint (Ti)) then
17049 Search_Derivation_Levels
17050 (Td, Stored_Constraint (Ti), True);
17053 Search_Derivation_Levels
17054 (Td, Discrim_Values, Stored_Discrim_Values);
17060 -- Extra underlying places to search, if not found above. For
17061 -- concurrent types, the relevant discriminant appears in the
17062 -- corresponding record. For a type derived from a private type
17063 -- without discriminant, the full view inherits the discriminants
17064 -- of the full view of the parent.
17066 if Result = Discriminant then
17067 if Is_Concurrent_Type (Ti)
17068 and then Present (Corresponding_Record_Type (Ti))
17071 Search_Derivation_Levels (
17072 Corresponding_Record_Type (Ti),
17074 Stored_Discrim_Values);
17076 elsif Is_Private_Type (Ti)
17077 and then not Has_Discriminants (Ti)
17078 and then Present (Full_View (Ti))
17079 and then Etype (Full_View (Ti)) /= Ti
17082 Search_Derivation_Levels (
17085 Stored_Discrim_Values);
17089 -- If Result is not a (reference to a) discriminant, return it,
17090 -- otherwise set Result_Entity to the discriminant.
17092 if Nkind (Result) = N_Defining_Identifier then
17093 pragma Assert (Result = Discriminant);
17094 Result_Entity := Result;
17097 if not Denotes_Discriminant (Result) then
17101 Result_Entity := Entity (Result);
17104 -- See if this level of derivation actually has discriminants because
17105 -- tagged derivations can add them, hence the lower levels need not
17108 if not Has_Discriminants (Ti) then
17112 -- Scan Ti's discriminants for Result_Entity, and return its
17113 -- corresponding value, if any.
17115 Result_Entity := Original_Record_Component (Result_Entity);
17117 Assoc := First_Elmt (Discrim_Values);
17119 if Stored_Discrim_Values then
17120 Disc := First_Stored_Discriminant (Ti);
17122 Disc := First_Discriminant (Ti);
17125 while Present (Disc) loop
17126 pragma Assert (Present (Assoc));
17128 if Original_Record_Component (Disc) = Result_Entity then
17129 return Node (Assoc);
17134 if Stored_Discrim_Values then
17135 Next_Stored_Discriminant (Disc);
17137 Next_Discriminant (Disc);
17141 -- Could not find it
17144 end Search_Derivation_Levels;
17148 Result : Node_Or_Entity_Id;
17150 -- Start of processing for Get_Discriminant_Value
17153 -- ??? This routine is a gigantic mess and will be deleted. For the
17154 -- time being just test for the trivial case before calling recurse.
17156 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
17162 D := First_Discriminant (Typ_For_Constraint);
17163 E := First_Elmt (Constraint);
17164 while Present (D) loop
17165 if Chars (D) = Chars (Discriminant) then
17169 Next_Discriminant (D);
17175 Result := Search_Derivation_Levels
17176 (Typ_For_Constraint, Constraint, False);
17178 -- ??? hack to disappear when this routine is gone
17180 if Nkind (Result) = N_Defining_Identifier then
17186 D := First_Discriminant (Typ_For_Constraint);
17187 E := First_Elmt (Constraint);
17188 while Present (D) loop
17189 if Root_Corresponding_Discriminant (D) = Discriminant then
17193 Next_Discriminant (D);
17199 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
17201 end Get_Discriminant_Value;
17203 --------------------------
17204 -- Has_Range_Constraint --
17205 --------------------------
17207 function Has_Range_Constraint (N : Node_Id) return Boolean is
17208 C : constant Node_Id := Constraint (N);
17211 if Nkind (C) = N_Range_Constraint then
17214 elsif Nkind (C) = N_Digits_Constraint then
17216 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
17217 or else Present (Range_Constraint (C));
17219 elsif Nkind (C) = N_Delta_Constraint then
17220 return Present (Range_Constraint (C));
17225 end Has_Range_Constraint;
17227 ------------------------
17228 -- Inherit_Components --
17229 ------------------------
17231 function Inherit_Components
17233 Parent_Base : Entity_Id;
17234 Derived_Base : Entity_Id;
17235 Is_Tagged : Boolean;
17236 Inherit_Discr : Boolean;
17237 Discs : Elist_Id) return Elist_Id
17239 Assoc_List : constant Elist_Id := New_Elmt_List;
17241 procedure Inherit_Component
17242 (Old_C : Entity_Id;
17243 Plain_Discrim : Boolean := False;
17244 Stored_Discrim : Boolean := False);
17245 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
17246 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
17247 -- True, Old_C is a stored discriminant. If they are both false then
17248 -- Old_C is a regular component.
17250 -----------------------
17251 -- Inherit_Component --
17252 -----------------------
17254 procedure Inherit_Component
17255 (Old_C : Entity_Id;
17256 Plain_Discrim : Boolean := False;
17257 Stored_Discrim : Boolean := False)
17259 procedure Set_Anonymous_Type (Id : Entity_Id);
17260 -- Id denotes the entity of an access discriminant or anonymous
17261 -- access component. Set the type of Id to either the same type of
17262 -- Old_C or create a new one depending on whether the parent and
17263 -- the child types are in the same scope.
17265 ------------------------
17266 -- Set_Anonymous_Type --
17267 ------------------------
17269 procedure Set_Anonymous_Type (Id : Entity_Id) is
17270 Old_Typ : constant Entity_Id := Etype (Old_C);
17273 if Scope (Parent_Base) = Scope (Derived_Base) then
17274 Set_Etype (Id, Old_Typ);
17276 -- The parent and the derived type are in two different scopes.
17277 -- Reuse the type of the original discriminant / component by
17278 -- copying it in order to preserve all attributes.
17282 Typ : constant Entity_Id := New_Copy (Old_Typ);
17285 Set_Etype (Id, Typ);
17287 -- Since we do not generate component declarations for
17288 -- inherited components, associate the itype with the
17291 Set_Associated_Node_For_Itype (Typ, Parent (Derived_Base));
17292 Set_Scope (Typ, Derived_Base);
17295 end Set_Anonymous_Type;
17297 -- Local variables and constants
17299 New_C : constant Entity_Id := New_Copy (Old_C);
17301 Corr_Discrim : Entity_Id;
17302 Discrim : Entity_Id;
17304 -- Start of processing for Inherit_Component
17307 pragma Assert (not Is_Tagged or not Stored_Discrim);
17309 Set_Parent (New_C, Parent (Old_C));
17311 -- Regular discriminants and components must be inserted in the scope
17312 -- of the Derived_Base. Do it here.
17314 if not Stored_Discrim then
17315 Enter_Name (New_C);
17318 -- For tagged types the Original_Record_Component must point to
17319 -- whatever this field was pointing to in the parent type. This has
17320 -- already been achieved by the call to New_Copy above.
17322 if not Is_Tagged then
17323 Set_Original_Record_Component (New_C, New_C);
17326 -- Set the proper type of an access discriminant
17328 if Ekind (New_C) = E_Discriminant
17329 and then Ekind (Etype (New_C)) = E_Anonymous_Access_Type
17331 Set_Anonymous_Type (New_C);
17334 -- If we have inherited a component then see if its Etype contains
17335 -- references to Parent_Base discriminants. In this case, replace
17336 -- these references with the constraints given in Discs. We do not
17337 -- do this for the partial view of private types because this is
17338 -- not needed (only the components of the full view will be used
17339 -- for code generation) and cause problem. We also avoid this
17340 -- transformation in some error situations.
17342 if Ekind (New_C) = E_Component then
17344 -- Set the proper type of an anonymous access component
17346 if Ekind (Etype (New_C)) = E_Anonymous_Access_Type then
17347 Set_Anonymous_Type (New_C);
17349 elsif (Is_Private_Type (Derived_Base)
17350 and then not Is_Generic_Type (Derived_Base))
17351 or else (Is_Empty_Elmt_List (Discs)
17352 and then not Expander_Active)
17354 Set_Etype (New_C, Etype (Old_C));
17357 -- The current component introduces a circularity of the
17360 -- limited with Pack_2;
17361 -- package Pack_1 is
17362 -- type T_1 is tagged record
17363 -- Comp : access Pack_2.T_2;
17369 -- package Pack_2 is
17370 -- type T_2 is new Pack_1.T_1 with ...;
17375 Constrain_Component_Type
17376 (Old_C, Derived_Base, N, Parent_Base, Discs));
17380 -- In derived tagged types it is illegal to reference a non
17381 -- discriminant component in the parent type. To catch this, mark
17382 -- these components with an Ekind of E_Void. This will be reset in
17383 -- Record_Type_Definition after processing the record extension of
17384 -- the derived type.
17386 -- If the declaration is a private extension, there is no further
17387 -- record extension to process, and the components retain their
17388 -- current kind, because they are visible at this point.
17390 if Is_Tagged and then Ekind (New_C) = E_Component
17391 and then Nkind (N) /= N_Private_Extension_Declaration
17393 Set_Ekind (New_C, E_Void);
17396 if Plain_Discrim then
17397 Set_Corresponding_Discriminant (New_C, Old_C);
17398 Build_Discriminal (New_C);
17400 -- If we are explicitly inheriting a stored discriminant it will be
17401 -- completely hidden.
17403 elsif Stored_Discrim then
17404 Set_Corresponding_Discriminant (New_C, Empty);
17405 Set_Discriminal (New_C, Empty);
17406 Set_Is_Completely_Hidden (New_C);
17408 -- Set the Original_Record_Component of each discriminant in the
17409 -- derived base to point to the corresponding stored that we just
17412 Discrim := First_Discriminant (Derived_Base);
17413 while Present (Discrim) loop
17414 Corr_Discrim := Corresponding_Discriminant (Discrim);
17416 -- Corr_Discrim could be missing in an error situation
17418 if Present (Corr_Discrim)
17419 and then Original_Record_Component (Corr_Discrim) = Old_C
17421 Set_Original_Record_Component (Discrim, New_C);
17424 Next_Discriminant (Discrim);
17427 Append_Entity (New_C, Derived_Base);
17430 if not Is_Tagged then
17431 Append_Elmt (Old_C, Assoc_List);
17432 Append_Elmt (New_C, Assoc_List);
17434 end Inherit_Component;
17436 -- Variables local to Inherit_Component
17438 Loc : constant Source_Ptr := Sloc (N);
17440 Parent_Discrim : Entity_Id;
17441 Stored_Discrim : Entity_Id;
17443 Component : Entity_Id;
17445 -- Start of processing for Inherit_Components
17448 if not Is_Tagged then
17449 Append_Elmt (Parent_Base, Assoc_List);
17450 Append_Elmt (Derived_Base, Assoc_List);
17453 -- Inherit parent discriminants if needed
17455 if Inherit_Discr then
17456 Parent_Discrim := First_Discriminant (Parent_Base);
17457 while Present (Parent_Discrim) loop
17458 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
17459 Next_Discriminant (Parent_Discrim);
17463 -- Create explicit stored discrims for untagged types when necessary
17465 if not Has_Unknown_Discriminants (Derived_Base)
17466 and then Has_Discriminants (Parent_Base)
17467 and then not Is_Tagged
17470 or else First_Discriminant (Parent_Base) /=
17471 First_Stored_Discriminant (Parent_Base))
17473 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
17474 while Present (Stored_Discrim) loop
17475 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
17476 Next_Stored_Discriminant (Stored_Discrim);
17480 -- See if we can apply the second transformation for derived types, as
17481 -- explained in point 6. in the comments above Build_Derived_Record_Type
17482 -- This is achieved by appending Derived_Base discriminants into Discs,
17483 -- which has the side effect of returning a non empty Discs list to the
17484 -- caller of Inherit_Components, which is what we want. This must be
17485 -- done for private derived types if there are explicit stored
17486 -- discriminants, to ensure that we can retrieve the values of the
17487 -- constraints provided in the ancestors.
17490 and then Is_Empty_Elmt_List (Discs)
17491 and then Present (First_Discriminant (Derived_Base))
17493 (not Is_Private_Type (Derived_Base)
17494 or else Is_Completely_Hidden
17495 (First_Stored_Discriminant (Derived_Base))
17496 or else Is_Generic_Type (Derived_Base))
17498 D := First_Discriminant (Derived_Base);
17499 while Present (D) loop
17500 Append_Elmt (New_Occurrence_Of (D, Loc), Discs);
17501 Next_Discriminant (D);
17505 -- Finally, inherit non-discriminant components unless they are not
17506 -- visible because defined or inherited from the full view of the
17507 -- parent. Don't inherit the _parent field of the parent type.
17509 Component := First_Entity (Parent_Base);
17510 while Present (Component) loop
17512 -- Ada 2005 (AI-251): Do not inherit components associated with
17513 -- secondary tags of the parent.
17515 if Ekind (Component) = E_Component
17516 and then Present (Related_Type (Component))
17520 elsif Ekind (Component) /= E_Component
17521 or else Chars (Component) = Name_uParent
17525 -- If the derived type is within the parent type's declarative
17526 -- region, then the components can still be inherited even though
17527 -- they aren't visible at this point. This can occur for cases
17528 -- such as within public child units where the components must
17529 -- become visible upon entering the child unit's private part.
17531 elsif not Is_Visible_Component (Component)
17532 and then not In_Open_Scopes (Scope (Parent_Base))
17536 elsif Ekind_In (Derived_Base, E_Private_Type,
17537 E_Limited_Private_Type)
17542 Inherit_Component (Component);
17545 Next_Entity (Component);
17548 -- For tagged derived types, inherited discriminants cannot be used in
17549 -- component declarations of the record extension part. To achieve this
17550 -- we mark the inherited discriminants as not visible.
17552 if Is_Tagged and then Inherit_Discr then
17553 D := First_Discriminant (Derived_Base);
17554 while Present (D) loop
17555 Set_Is_Immediately_Visible (D, False);
17556 Next_Discriminant (D);
17561 end Inherit_Components;
17563 -----------------------------
17564 -- Inherit_Predicate_Flags --
17565 -----------------------------
17567 procedure Inherit_Predicate_Flags (Subt, Par : Entity_Id) is
17569 Set_Has_Predicates (Subt, Has_Predicates (Par));
17570 Set_Has_Static_Predicate_Aspect
17571 (Subt, Has_Static_Predicate_Aspect (Par));
17572 Set_Has_Dynamic_Predicate_Aspect
17573 (Subt, Has_Dynamic_Predicate_Aspect (Par));
17574 end Inherit_Predicate_Flags;
17576 ----------------------
17577 -- Is_EVF_Procedure --
17578 ----------------------
17580 function Is_EVF_Procedure (Subp : Entity_Id) return Boolean is
17581 Formal : Entity_Id;
17584 -- Examine the formals of an Extensions_Visible False procedure looking
17585 -- for a controlling OUT parameter.
17587 if Ekind (Subp) = E_Procedure
17588 and then Extensions_Visible_Status (Subp) = Extensions_Visible_False
17590 Formal := First_Formal (Subp);
17591 while Present (Formal) loop
17592 if Ekind (Formal) = E_Out_Parameter
17593 and then Is_Controlling_Formal (Formal)
17598 Next_Formal (Formal);
17603 end Is_EVF_Procedure;
17605 -----------------------
17606 -- Is_Null_Extension --
17607 -----------------------
17609 function Is_Null_Extension (T : Entity_Id) return Boolean is
17610 Type_Decl : constant Node_Id := Parent (Base_Type (T));
17611 Comp_List : Node_Id;
17615 if Nkind (Type_Decl) /= N_Full_Type_Declaration
17616 or else not Is_Tagged_Type (T)
17617 or else Nkind (Type_Definition (Type_Decl)) /=
17618 N_Derived_Type_Definition
17619 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
17625 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
17627 if Present (Discriminant_Specifications (Type_Decl)) then
17630 elsif Present (Comp_List)
17631 and then Is_Non_Empty_List (Component_Items (Comp_List))
17633 Comp := First (Component_Items (Comp_List));
17635 -- Only user-defined components are relevant. The component list
17636 -- may also contain a parent component and internal components
17637 -- corresponding to secondary tags, but these do not determine
17638 -- whether this is a null extension.
17640 while Present (Comp) loop
17641 if Comes_From_Source (Comp) then
17653 end Is_Null_Extension;
17655 ------------------------------
17656 -- Is_Valid_Constraint_Kind --
17657 ------------------------------
17659 function Is_Valid_Constraint_Kind
17660 (T_Kind : Type_Kind;
17661 Constraint_Kind : Node_Kind) return Boolean
17665 when Enumeration_Kind |
17667 return Constraint_Kind = N_Range_Constraint;
17669 when Decimal_Fixed_Point_Kind =>
17670 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
17671 N_Range_Constraint);
17673 when Ordinary_Fixed_Point_Kind =>
17674 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
17675 N_Range_Constraint);
17678 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
17679 N_Range_Constraint);
17686 E_Incomplete_Type |
17689 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
17692 return True; -- Error will be detected later
17694 end Is_Valid_Constraint_Kind;
17696 --------------------------
17697 -- Is_Visible_Component --
17698 --------------------------
17700 function Is_Visible_Component
17702 N : Node_Id := Empty) return Boolean
17704 Original_Comp : Entity_Id := Empty;
17705 Original_Scope : Entity_Id;
17706 Type_Scope : Entity_Id;
17708 function Is_Local_Type (Typ : Entity_Id) return Boolean;
17709 -- Check whether parent type of inherited component is declared locally,
17710 -- possibly within a nested package or instance. The current scope is
17711 -- the derived record itself.
17713 -------------------
17714 -- Is_Local_Type --
17715 -------------------
17717 function Is_Local_Type (Typ : Entity_Id) return Boolean is
17721 Scop := Scope (Typ);
17722 while Present (Scop)
17723 and then Scop /= Standard_Standard
17725 if Scop = Scope (Current_Scope) then
17729 Scop := Scope (Scop);
17735 -- Start of processing for Is_Visible_Component
17738 if Ekind_In (C, E_Component, E_Discriminant) then
17739 Original_Comp := Original_Record_Component (C);
17742 if No (Original_Comp) then
17744 -- Premature usage, or previous error
17749 Original_Scope := Scope (Original_Comp);
17750 Type_Scope := Scope (Base_Type (Scope (C)));
17753 -- This test only concerns tagged types
17755 if not Is_Tagged_Type (Original_Scope) then
17758 -- If it is _Parent or _Tag, there is no visibility issue
17760 elsif not Comes_From_Source (Original_Comp) then
17763 -- Discriminants are visible unless the (private) type has unknown
17764 -- discriminants. If the discriminant reference is inserted for a
17765 -- discriminant check on a full view it is also visible.
17767 elsif Ekind (Original_Comp) = E_Discriminant
17769 (not Has_Unknown_Discriminants (Original_Scope)
17770 or else (Present (N)
17771 and then Nkind (N) = N_Selected_Component
17772 and then Nkind (Prefix (N)) = N_Type_Conversion
17773 and then not Comes_From_Source (Prefix (N))))
17777 -- In the body of an instantiation, no need to check for the visibility
17780 elsif In_Instance_Body then
17783 -- If the component has been declared in an ancestor which is currently
17784 -- a private type, then it is not visible. The same applies if the
17785 -- component's containing type is not in an open scope and the original
17786 -- component's enclosing type is a visible full view of a private type
17787 -- (which can occur in cases where an attempt is being made to reference
17788 -- a component in a sibling package that is inherited from a visible
17789 -- component of a type in an ancestor package; the component in the
17790 -- sibling package should not be visible even though the component it
17791 -- inherited from is visible). This does not apply however in the case
17792 -- where the scope of the type is a private child unit, or when the
17793 -- parent comes from a local package in which the ancestor is currently
17794 -- visible. The latter suppression of visibility is needed for cases
17795 -- that are tested in B730006.
17797 elsif Is_Private_Type (Original_Scope)
17799 (not Is_Private_Descendant (Type_Scope)
17800 and then not In_Open_Scopes (Type_Scope)
17801 and then Has_Private_Declaration (Original_Scope))
17803 -- If the type derives from an entity in a formal package, there
17804 -- are no additional visible components.
17806 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
17807 N_Formal_Package_Declaration
17811 -- if we are not in the private part of the current package, there
17812 -- are no additional visible components.
17814 elsif Ekind (Scope (Current_Scope)) = E_Package
17815 and then not In_Private_Part (Scope (Current_Scope))
17820 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
17821 and then In_Open_Scopes (Scope (Original_Scope))
17822 and then Is_Local_Type (Type_Scope);
17825 -- There is another weird way in which a component may be invisible when
17826 -- the private and the full view are not derived from the same ancestor.
17827 -- Here is an example :
17829 -- type A1 is tagged record F1 : integer; end record;
17830 -- type A2 is new A1 with record F2 : integer; end record;
17831 -- type T is new A1 with private;
17833 -- type T is new A2 with null record;
17835 -- In this case, the full view of T inherits F1 and F2 but the private
17836 -- view inherits only F1
17840 Ancestor : Entity_Id := Scope (C);
17844 if Ancestor = Original_Scope then
17846 elsif Ancestor = Etype (Ancestor) then
17850 Ancestor := Etype (Ancestor);
17854 end Is_Visible_Component;
17856 --------------------------
17857 -- Make_Class_Wide_Type --
17858 --------------------------
17860 procedure Make_Class_Wide_Type (T : Entity_Id) is
17861 CW_Type : Entity_Id;
17863 Next_E : Entity_Id;
17866 if Present (Class_Wide_Type (T)) then
17868 -- The class-wide type is a partially decorated entity created for a
17869 -- unanalyzed tagged type referenced through a limited with clause.
17870 -- When the tagged type is analyzed, its class-wide type needs to be
17871 -- redecorated. Note that we reuse the entity created by Decorate_
17872 -- Tagged_Type in order to preserve all links.
17874 if Materialize_Entity (Class_Wide_Type (T)) then
17875 CW_Type := Class_Wide_Type (T);
17876 Set_Materialize_Entity (CW_Type, False);
17878 -- The class wide type can have been defined by the partial view, in
17879 -- which case everything is already done.
17885 -- Default case, we need to create a new class-wide type
17889 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
17892 -- Inherit root type characteristics
17894 CW_Name := Chars (CW_Type);
17895 Next_E := Next_Entity (CW_Type);
17896 Copy_Node (T, CW_Type);
17897 Set_Comes_From_Source (CW_Type, False);
17898 Set_Chars (CW_Type, CW_Name);
17899 Set_Parent (CW_Type, Parent (T));
17900 Set_Next_Entity (CW_Type, Next_E);
17902 -- Ensure we have a new freeze node for the class-wide type. The partial
17903 -- view may have freeze action of its own, requiring a proper freeze
17904 -- node, and the same freeze node cannot be shared between the two
17907 Set_Has_Delayed_Freeze (CW_Type);
17908 Set_Freeze_Node (CW_Type, Empty);
17910 -- Customize the class-wide type: It has no prim. op., it cannot be
17911 -- abstract and its Etype points back to the specific root type.
17913 Set_Ekind (CW_Type, E_Class_Wide_Type);
17914 Set_Is_Tagged_Type (CW_Type, True);
17915 Set_Direct_Primitive_Operations (CW_Type, New_Elmt_List);
17916 Set_Is_Abstract_Type (CW_Type, False);
17917 Set_Is_Constrained (CW_Type, False);
17918 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
17919 Set_Default_SSO (CW_Type);
17921 if Ekind (T) = E_Class_Wide_Subtype then
17922 Set_Etype (CW_Type, Etype (Base_Type (T)));
17924 Set_Etype (CW_Type, T);
17927 Set_No_Tagged_Streams_Pragma (CW_Type, No_Tagged_Streams);
17929 -- If this is the class_wide type of a constrained subtype, it does
17930 -- not have discriminants.
17932 Set_Has_Discriminants (CW_Type,
17933 Has_Discriminants (T) and then not Is_Constrained (T));
17935 Set_Has_Unknown_Discriminants (CW_Type, True);
17936 Set_Class_Wide_Type (T, CW_Type);
17937 Set_Equivalent_Type (CW_Type, Empty);
17939 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
17941 Set_Class_Wide_Type (CW_Type, CW_Type);
17942 end Make_Class_Wide_Type;
17948 procedure Make_Index
17950 Related_Nod : Node_Id;
17951 Related_Id : Entity_Id := Empty;
17952 Suffix_Index : Nat := 1;
17953 In_Iter_Schm : Boolean := False)
17957 Def_Id : Entity_Id := Empty;
17958 Found : Boolean := False;
17961 -- For a discrete range used in a constrained array definition and
17962 -- defined by a range, an implicit conversion to the predefined type
17963 -- INTEGER is assumed if each bound is either a numeric literal, a named
17964 -- number, or an attribute, and the type of both bounds (prior to the
17965 -- implicit conversion) is the type universal_integer. Otherwise, both
17966 -- bounds must be of the same discrete type, other than universal
17967 -- integer; this type must be determinable independently of the
17968 -- context, but using the fact that the type must be discrete and that
17969 -- both bounds must have the same type.
17971 -- Character literals also have a universal type in the absence of
17972 -- of additional context, and are resolved to Standard_Character.
17974 if Nkind (N) = N_Range then
17976 -- The index is given by a range constraint. The bounds are known
17977 -- to be of a consistent type.
17979 if not Is_Overloaded (N) then
17982 -- For universal bounds, choose the specific predefined type
17984 if T = Universal_Integer then
17985 T := Standard_Integer;
17987 elsif T = Any_Character then
17988 Ambiguous_Character (Low_Bound (N));
17990 T := Standard_Character;
17993 -- The node may be overloaded because some user-defined operators
17994 -- are available, but if a universal interpretation exists it is
17995 -- also the selected one.
17997 elsif Universal_Interpretation (N) = Universal_Integer then
17998 T := Standard_Integer;
18004 Ind : Interp_Index;
18008 Get_First_Interp (N, Ind, It);
18009 while Present (It.Typ) loop
18010 if Is_Discrete_Type (It.Typ) then
18013 and then not Covers (It.Typ, T)
18014 and then not Covers (T, It.Typ)
18016 Error_Msg_N ("ambiguous bounds in discrete range", N);
18024 Get_Next_Interp (Ind, It);
18027 if T = Any_Type then
18028 Error_Msg_N ("discrete type required for range", N);
18029 Set_Etype (N, Any_Type);
18032 elsif T = Universal_Integer then
18033 T := Standard_Integer;
18038 if not Is_Discrete_Type (T) then
18039 Error_Msg_N ("discrete type required for range", N);
18040 Set_Etype (N, Any_Type);
18044 if Nkind (Low_Bound (N)) = N_Attribute_Reference
18045 and then Attribute_Name (Low_Bound (N)) = Name_First
18046 and then Is_Entity_Name (Prefix (Low_Bound (N)))
18047 and then Is_Type (Entity (Prefix (Low_Bound (N))))
18048 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (N))))
18050 -- The type of the index will be the type of the prefix, as long
18051 -- as the upper bound is 'Last of the same type.
18053 Def_Id := Entity (Prefix (Low_Bound (N)));
18055 if Nkind (High_Bound (N)) /= N_Attribute_Reference
18056 or else Attribute_Name (High_Bound (N)) /= Name_Last
18057 or else not Is_Entity_Name (Prefix (High_Bound (N)))
18058 or else Entity (Prefix (High_Bound (N))) /= Def_Id
18065 Process_Range_Expr_In_Decl (R, T, In_Iter_Schm => In_Iter_Schm);
18067 elsif Nkind (N) = N_Subtype_Indication then
18069 -- The index is given by a subtype with a range constraint
18071 T := Base_Type (Entity (Subtype_Mark (N)));
18073 if not Is_Discrete_Type (T) then
18074 Error_Msg_N ("discrete type required for range", N);
18075 Set_Etype (N, Any_Type);
18079 R := Range_Expression (Constraint (N));
18082 Process_Range_Expr_In_Decl
18083 (R, Entity (Subtype_Mark (N)), In_Iter_Schm => In_Iter_Schm);
18085 elsif Nkind (N) = N_Attribute_Reference then
18087 -- Catch beginner's error (use of attribute other than 'Range)
18089 if Attribute_Name (N) /= Name_Range then
18090 Error_Msg_N ("expect attribute ''Range", N);
18091 Set_Etype (N, Any_Type);
18095 -- If the node denotes the range of a type mark, that is also the
18096 -- resulting type, and we do not need to create an Itype for it.
18098 if Is_Entity_Name (Prefix (N))
18099 and then Comes_From_Source (N)
18100 and then Is_Type (Entity (Prefix (N)))
18101 and then Is_Discrete_Type (Entity (Prefix (N)))
18103 Def_Id := Entity (Prefix (N));
18106 Analyze_And_Resolve (N);
18110 -- If none of the above, must be a subtype. We convert this to a
18111 -- range attribute reference because in the case of declared first
18112 -- named subtypes, the types in the range reference can be different
18113 -- from the type of the entity. A range attribute normalizes the
18114 -- reference and obtains the correct types for the bounds.
18116 -- This transformation is in the nature of an expansion, is only
18117 -- done if expansion is active. In particular, it is not done on
18118 -- formal generic types, because we need to retain the name of the
18119 -- original index for instantiation purposes.
18122 if not Is_Entity_Name (N) or else not Is_Type (Entity (N)) then
18123 Error_Msg_N ("invalid subtype mark in discrete range ", N);
18124 Set_Etype (N, Any_Integer);
18128 -- The type mark may be that of an incomplete type. It is only
18129 -- now that we can get the full view, previous analysis does
18130 -- not look specifically for a type mark.
18132 Set_Entity (N, Get_Full_View (Entity (N)));
18133 Set_Etype (N, Entity (N));
18134 Def_Id := Entity (N);
18136 if not Is_Discrete_Type (Def_Id) then
18137 Error_Msg_N ("discrete type required for index", N);
18138 Set_Etype (N, Any_Type);
18143 if Expander_Active then
18145 Make_Attribute_Reference (Sloc (N),
18146 Attribute_Name => Name_Range,
18147 Prefix => Relocate_Node (N)));
18149 -- The original was a subtype mark that does not freeze. This
18150 -- means that the rewritten version must not freeze either.
18152 Set_Must_Not_Freeze (N);
18153 Set_Must_Not_Freeze (Prefix (N));
18154 Analyze_And_Resolve (N);
18158 -- If expander is inactive, type is legal, nothing else to construct
18165 if not Is_Discrete_Type (T) then
18166 Error_Msg_N ("discrete type required for range", N);
18167 Set_Etype (N, Any_Type);
18170 elsif T = Any_Type then
18171 Set_Etype (N, Any_Type);
18175 -- We will now create the appropriate Itype to describe the range, but
18176 -- first a check. If we originally had a subtype, then we just label
18177 -- the range with this subtype. Not only is there no need to construct
18178 -- a new subtype, but it is wrong to do so for two reasons:
18180 -- 1. A legality concern, if we have a subtype, it must not freeze,
18181 -- and the Itype would cause freezing incorrectly
18183 -- 2. An efficiency concern, if we created an Itype, it would not be
18184 -- recognized as the same type for the purposes of eliminating
18185 -- checks in some circumstances.
18187 -- We signal this case by setting the subtype entity in Def_Id
18189 if No (Def_Id) then
18191 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
18192 Set_Etype (Def_Id, Base_Type (T));
18194 if Is_Signed_Integer_Type (T) then
18195 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
18197 elsif Is_Modular_Integer_Type (T) then
18198 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
18201 Set_Ekind (Def_Id, E_Enumeration_Subtype);
18202 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
18203 Set_First_Literal (Def_Id, First_Literal (T));
18206 Set_Size_Info (Def_Id, (T));
18207 Set_RM_Size (Def_Id, RM_Size (T));
18208 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
18210 Set_Scalar_Range (Def_Id, R);
18211 Conditional_Delay (Def_Id, T);
18213 if Nkind (N) = N_Subtype_Indication then
18214 Inherit_Predicate_Flags (Def_Id, Entity (Subtype_Mark (N)));
18217 -- In the subtype indication case, if the immediate parent of the
18218 -- new subtype is non-static, then the subtype we create is non-
18219 -- static, even if its bounds are static.
18221 if Nkind (N) = N_Subtype_Indication
18222 and then not Is_OK_Static_Subtype (Entity (Subtype_Mark (N)))
18224 Set_Is_Non_Static_Subtype (Def_Id);
18228 -- Final step is to label the index with this constructed type
18230 Set_Etype (N, Def_Id);
18233 ------------------------------
18234 -- Modular_Type_Declaration --
18235 ------------------------------
18237 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
18238 Mod_Expr : constant Node_Id := Expression (Def);
18241 procedure Set_Modular_Size (Bits : Int);
18242 -- Sets RM_Size to Bits, and Esize to normal word size above this
18244 ----------------------
18245 -- Set_Modular_Size --
18246 ----------------------
18248 procedure Set_Modular_Size (Bits : Int) is
18250 Set_RM_Size (T, UI_From_Int (Bits));
18255 elsif Bits <= 16 then
18256 Init_Esize (T, 16);
18258 elsif Bits <= 32 then
18259 Init_Esize (T, 32);
18262 Init_Esize (T, System_Max_Binary_Modulus_Power);
18265 if not Non_Binary_Modulus (T) and then Esize (T) = RM_Size (T) then
18266 Set_Is_Known_Valid (T);
18268 end Set_Modular_Size;
18270 -- Start of processing for Modular_Type_Declaration
18273 -- If the mod expression is (exactly) 2 * literal, where literal is
18274 -- 64 or less,then almost certainly the * was meant to be **. Warn.
18276 if Warn_On_Suspicious_Modulus_Value
18277 and then Nkind (Mod_Expr) = N_Op_Multiply
18278 and then Nkind (Left_Opnd (Mod_Expr)) = N_Integer_Literal
18279 and then Intval (Left_Opnd (Mod_Expr)) = Uint_2
18280 and then Nkind (Right_Opnd (Mod_Expr)) = N_Integer_Literal
18281 and then Intval (Right_Opnd (Mod_Expr)) <= Uint_64
18284 ("suspicious MOD value, was '*'* intended'??M?", Mod_Expr);
18287 -- Proceed with analysis of mod expression
18289 Analyze_And_Resolve (Mod_Expr, Any_Integer);
18291 Set_Ekind (T, E_Modular_Integer_Type);
18292 Init_Alignment (T);
18293 Set_Is_Constrained (T);
18295 if not Is_OK_Static_Expression (Mod_Expr) then
18296 Flag_Non_Static_Expr
18297 ("non-static expression used for modular type bound!", Mod_Expr);
18298 M_Val := 2 ** System_Max_Binary_Modulus_Power;
18300 M_Val := Expr_Value (Mod_Expr);
18304 Error_Msg_N ("modulus value must be positive", Mod_Expr);
18305 M_Val := 2 ** System_Max_Binary_Modulus_Power;
18308 if M_Val > 2 ** Standard_Long_Integer_Size then
18309 Check_Restriction (No_Long_Long_Integers, Mod_Expr);
18312 Set_Modulus (T, M_Val);
18314 -- Create bounds for the modular type based on the modulus given in
18315 -- the type declaration and then analyze and resolve those bounds.
18317 Set_Scalar_Range (T,
18318 Make_Range (Sloc (Mod_Expr),
18319 Low_Bound => Make_Integer_Literal (Sloc (Mod_Expr), 0),
18320 High_Bound => Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
18322 -- Properly analyze the literals for the range. We do this manually
18323 -- because we can't go calling Resolve, since we are resolving these
18324 -- bounds with the type, and this type is certainly not complete yet.
18326 Set_Etype (Low_Bound (Scalar_Range (T)), T);
18327 Set_Etype (High_Bound (Scalar_Range (T)), T);
18328 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
18329 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
18331 -- Loop through powers of two to find number of bits required
18333 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
18337 if M_Val = 2 ** Bits then
18338 Set_Modular_Size (Bits);
18343 elsif M_Val < 2 ** Bits then
18344 Check_SPARK_05_Restriction ("modulus should be a power of 2", T);
18345 Set_Non_Binary_Modulus (T);
18347 if Bits > System_Max_Nonbinary_Modulus_Power then
18348 Error_Msg_Uint_1 :=
18349 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
18351 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
18352 Set_Modular_Size (System_Max_Binary_Modulus_Power);
18356 -- In the non-binary case, set size as per RM 13.3(55)
18358 Set_Modular_Size (Bits);
18365 -- If we fall through, then the size exceed System.Max_Binary_Modulus
18366 -- so we just signal an error and set the maximum size.
18368 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
18369 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
18371 Set_Modular_Size (System_Max_Binary_Modulus_Power);
18372 Init_Alignment (T);
18374 end Modular_Type_Declaration;
18376 --------------------------
18377 -- New_Concatenation_Op --
18378 --------------------------
18380 procedure New_Concatenation_Op (Typ : Entity_Id) is
18381 Loc : constant Source_Ptr := Sloc (Typ);
18384 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
18385 -- Create abbreviated declaration for the formal of a predefined
18386 -- Operator 'Op' of type 'Typ'
18388 --------------------
18389 -- Make_Op_Formal --
18390 --------------------
18392 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
18393 Formal : Entity_Id;
18395 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
18396 Set_Etype (Formal, Typ);
18397 Set_Mechanism (Formal, Default_Mechanism);
18399 end Make_Op_Formal;
18401 -- Start of processing for New_Concatenation_Op
18404 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
18406 Set_Ekind (Op, E_Operator);
18407 Set_Scope (Op, Current_Scope);
18408 Set_Etype (Op, Typ);
18409 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
18410 Set_Is_Immediately_Visible (Op);
18411 Set_Is_Intrinsic_Subprogram (Op);
18412 Set_Has_Completion (Op);
18413 Append_Entity (Op, Current_Scope);
18415 Set_Name_Entity_Id (Name_Op_Concat, Op);
18417 Append_Entity (Make_Op_Formal (Typ, Op), Op);
18418 Append_Entity (Make_Op_Formal (Typ, Op), Op);
18419 end New_Concatenation_Op;
18421 -------------------------
18422 -- OK_For_Limited_Init --
18423 -------------------------
18425 -- ???Check all calls of this, and compare the conditions under which it's
18428 function OK_For_Limited_Init
18430 Exp : Node_Id) return Boolean
18433 return Is_CPP_Constructor_Call (Exp)
18434 or else (Ada_Version >= Ada_2005
18435 and then not Debug_Flag_Dot_L
18436 and then OK_For_Limited_Init_In_05 (Typ, Exp));
18437 end OK_For_Limited_Init;
18439 -------------------------------
18440 -- OK_For_Limited_Init_In_05 --
18441 -------------------------------
18443 function OK_For_Limited_Init_In_05
18445 Exp : Node_Id) return Boolean
18448 -- An object of a limited interface type can be initialized with any
18449 -- expression of a nonlimited descendant type.
18451 if Is_Class_Wide_Type (Typ)
18452 and then Is_Limited_Interface (Typ)
18453 and then not Is_Limited_Type (Etype (Exp))
18458 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
18459 -- case of limited aggregates (including extension aggregates), and
18460 -- function calls. The function call may have been given in prefixed
18461 -- notation, in which case the original node is an indexed component.
18462 -- If the function is parameterless, the original node was an explicit
18463 -- dereference. The function may also be parameterless, in which case
18464 -- the source node is just an identifier.
18466 case Nkind (Original_Node (Exp)) is
18467 when N_Aggregate | N_Extension_Aggregate | N_Function_Call | N_Op =>
18470 when N_Identifier =>
18471 return Present (Entity (Original_Node (Exp)))
18472 and then Ekind (Entity (Original_Node (Exp))) = E_Function;
18474 when N_Qualified_Expression =>
18476 OK_For_Limited_Init_In_05
18477 (Typ, Expression (Original_Node (Exp)));
18479 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
18480 -- with a function call, the expander has rewritten the call into an
18481 -- N_Type_Conversion node to force displacement of the pointer to
18482 -- reference the component containing the secondary dispatch table.
18483 -- Otherwise a type conversion is not a legal context.
18484 -- A return statement for a build-in-place function returning a
18485 -- synchronized type also introduces an unchecked conversion.
18487 when N_Type_Conversion |
18488 N_Unchecked_Type_Conversion =>
18489 return not Comes_From_Source (Exp)
18491 OK_For_Limited_Init_In_05
18492 (Typ, Expression (Original_Node (Exp)));
18494 when N_Indexed_Component |
18495 N_Selected_Component |
18496 N_Explicit_Dereference =>
18497 return Nkind (Exp) = N_Function_Call;
18499 -- A use of 'Input is a function call, hence allowed. Normally the
18500 -- attribute will be changed to a call, but the attribute by itself
18501 -- can occur with -gnatc.
18503 when N_Attribute_Reference =>
18504 return Attribute_Name (Original_Node (Exp)) = Name_Input;
18506 -- For a case expression, all dependent expressions must be legal
18508 when N_Case_Expression =>
18513 Alt := First (Alternatives (Original_Node (Exp)));
18514 while Present (Alt) loop
18515 if not OK_For_Limited_Init_In_05 (Typ, Expression (Alt)) then
18525 -- For an if expression, all dependent expressions must be legal
18527 when N_If_Expression =>
18529 Then_Expr : constant Node_Id :=
18530 Next (First (Expressions (Original_Node (Exp))));
18531 Else_Expr : constant Node_Id := Next (Then_Expr);
18533 return OK_For_Limited_Init_In_05 (Typ, Then_Expr)
18535 OK_For_Limited_Init_In_05 (Typ, Else_Expr);
18541 end OK_For_Limited_Init_In_05;
18543 -------------------------------------------
18544 -- Ordinary_Fixed_Point_Type_Declaration --
18545 -------------------------------------------
18547 procedure Ordinary_Fixed_Point_Type_Declaration
18551 Loc : constant Source_Ptr := Sloc (Def);
18552 Delta_Expr : constant Node_Id := Delta_Expression (Def);
18553 RRS : constant Node_Id := Real_Range_Specification (Def);
18554 Implicit_Base : Entity_Id;
18561 Check_Restriction (No_Fixed_Point, Def);
18563 -- Create implicit base type
18566 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
18567 Set_Etype (Implicit_Base, Implicit_Base);
18569 -- Analyze and process delta expression
18571 Analyze_And_Resolve (Delta_Expr, Any_Real);
18573 Check_Delta_Expression (Delta_Expr);
18574 Delta_Val := Expr_Value_R (Delta_Expr);
18576 Set_Delta_Value (Implicit_Base, Delta_Val);
18578 -- Compute default small from given delta, which is the largest power
18579 -- of two that does not exceed the given delta value.
18589 if Delta_Val < Ureal_1 then
18590 while Delta_Val < Tmp loop
18591 Tmp := Tmp / Ureal_2;
18592 Scale := Scale + 1;
18597 Tmp := Tmp * Ureal_2;
18598 exit when Tmp > Delta_Val;
18599 Scale := Scale - 1;
18603 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
18606 Set_Small_Value (Implicit_Base, Small_Val);
18608 -- If no range was given, set a dummy range
18610 if RRS <= Empty_Or_Error then
18611 Low_Val := -Small_Val;
18612 High_Val := Small_Val;
18614 -- Otherwise analyze and process given range
18618 Low : constant Node_Id := Low_Bound (RRS);
18619 High : constant Node_Id := High_Bound (RRS);
18622 Analyze_And_Resolve (Low, Any_Real);
18623 Analyze_And_Resolve (High, Any_Real);
18624 Check_Real_Bound (Low);
18625 Check_Real_Bound (High);
18627 -- Obtain and set the range
18629 Low_Val := Expr_Value_R (Low);
18630 High_Val := Expr_Value_R (High);
18632 if Low_Val > High_Val then
18633 Error_Msg_NE ("??fixed point type& has null range", Def, T);
18638 -- The range for both the implicit base and the declared first subtype
18639 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
18640 -- set a temporary range in place. Note that the bounds of the base
18641 -- type will be widened to be symmetrical and to fill the available
18642 -- bits when the type is frozen.
18644 -- We could do this with all discrete types, and probably should, but
18645 -- we absolutely have to do it for fixed-point, since the end-points
18646 -- of the range and the size are determined by the small value, which
18647 -- could be reset before the freeze point.
18649 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
18650 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
18652 -- Complete definition of first subtype. The inheritance of the rep item
18653 -- chain ensures that SPARK-related pragmas are not clobbered when the
18654 -- ordinary fixed point type acts as a full view of a private type.
18656 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
18657 Set_Etype (T, Implicit_Base);
18658 Init_Size_Align (T);
18659 Inherit_Rep_Item_Chain (T, Implicit_Base);
18660 Set_Small_Value (T, Small_Val);
18661 Set_Delta_Value (T, Delta_Val);
18662 Set_Is_Constrained (T);
18663 end Ordinary_Fixed_Point_Type_Declaration;
18665 ----------------------------------
18666 -- Preanalyze_Assert_Expression --
18667 ----------------------------------
18669 procedure Preanalyze_Assert_Expression (N : Node_Id; T : Entity_Id) is
18671 In_Assertion_Expr := In_Assertion_Expr + 1;
18672 Preanalyze_Spec_Expression (N, T);
18673 In_Assertion_Expr := In_Assertion_Expr - 1;
18674 end Preanalyze_Assert_Expression;
18676 -----------------------------------
18677 -- Preanalyze_Default_Expression --
18678 -----------------------------------
18680 procedure Preanalyze_Default_Expression (N : Node_Id; T : Entity_Id) is
18681 Save_In_Default_Expr : constant Boolean := In_Default_Expr;
18683 In_Default_Expr := True;
18684 Preanalyze_Spec_Expression (N, T);
18685 In_Default_Expr := Save_In_Default_Expr;
18686 end Preanalyze_Default_Expression;
18688 --------------------------------
18689 -- Preanalyze_Spec_Expression --
18690 --------------------------------
18692 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
18693 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
18695 In_Spec_Expression := True;
18696 Preanalyze_And_Resolve (N, T);
18697 In_Spec_Expression := Save_In_Spec_Expression;
18698 end Preanalyze_Spec_Expression;
18700 ----------------------------------------
18701 -- Prepare_Private_Subtype_Completion --
18702 ----------------------------------------
18704 procedure Prepare_Private_Subtype_Completion
18706 Related_Nod : Node_Id)
18708 Id_B : constant Entity_Id := Base_Type (Id);
18709 Full_B : Entity_Id := Full_View (Id_B);
18713 if Present (Full_B) then
18715 -- Get to the underlying full view if necessary
18717 if Is_Private_Type (Full_B)
18718 and then Present (Underlying_Full_View (Full_B))
18720 Full_B := Underlying_Full_View (Full_B);
18723 -- The Base_Type is already completed, we can complete the subtype
18724 -- now. We have to create a new entity with the same name, Thus we
18725 -- can't use Create_Itype.
18727 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
18728 Set_Is_Itype (Full);
18729 Set_Associated_Node_For_Itype (Full, Related_Nod);
18730 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
18733 -- The parent subtype may be private, but the base might not, in some
18734 -- nested instances. In that case, the subtype does not need to be
18735 -- exchanged. It would still be nice to make private subtypes and their
18736 -- bases consistent at all times ???
18738 if Is_Private_Type (Id_B) then
18739 Append_Elmt (Id, Private_Dependents (Id_B));
18741 end Prepare_Private_Subtype_Completion;
18743 ---------------------------
18744 -- Process_Discriminants --
18745 ---------------------------
18747 procedure Process_Discriminants
18749 Prev : Entity_Id := Empty)
18751 Elist : constant Elist_Id := New_Elmt_List;
18754 Discr_Number : Uint;
18755 Discr_Type : Entity_Id;
18756 Default_Present : Boolean := False;
18757 Default_Not_Present : Boolean := False;
18760 -- A composite type other than an array type can have discriminants.
18761 -- On entry, the current scope is the composite type.
18763 -- The discriminants are initially entered into the scope of the type
18764 -- via Enter_Name with the default Ekind of E_Void to prevent premature
18765 -- use, as explained at the end of this procedure.
18767 Discr := First (Discriminant_Specifications (N));
18768 while Present (Discr) loop
18769 Enter_Name (Defining_Identifier (Discr));
18771 -- For navigation purposes we add a reference to the discriminant
18772 -- in the entity for the type. If the current declaration is a
18773 -- completion, place references on the partial view. Otherwise the
18774 -- type is the current scope.
18776 if Present (Prev) then
18778 -- The references go on the partial view, if present. If the
18779 -- partial view has discriminants, the references have been
18780 -- generated already.
18782 if not Has_Discriminants (Prev) then
18783 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
18787 (Current_Scope, Defining_Identifier (Discr), 'd');
18790 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
18791 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
18793 -- Ada 2005 (AI-254)
18795 if Present (Access_To_Subprogram_Definition
18796 (Discriminant_Type (Discr)))
18797 and then Protected_Present (Access_To_Subprogram_Definition
18798 (Discriminant_Type (Discr)))
18801 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
18805 Find_Type (Discriminant_Type (Discr));
18806 Discr_Type := Etype (Discriminant_Type (Discr));
18808 if Error_Posted (Discriminant_Type (Discr)) then
18809 Discr_Type := Any_Type;
18813 -- Handling of discriminants that are access types
18815 if Is_Access_Type (Discr_Type) then
18817 -- Ada 2005 (AI-230): Access discriminant allowed in non-
18818 -- limited record types
18820 if Ada_Version < Ada_2005 then
18821 Check_Access_Discriminant_Requires_Limited
18822 (Discr, Discriminant_Type (Discr));
18825 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
18827 ("(Ada 83) access discriminant not allowed", Discr);
18830 -- If not access type, must be a discrete type
18832 elsif not Is_Discrete_Type (Discr_Type) then
18834 ("discriminants must have a discrete or access type",
18835 Discriminant_Type (Discr));
18838 Set_Etype (Defining_Identifier (Discr), Discr_Type);
18840 -- If a discriminant specification includes the assignment compound
18841 -- delimiter followed by an expression, the expression is the default
18842 -- expression of the discriminant; the default expression must be of
18843 -- the type of the discriminant. (RM 3.7.1) Since this expression is
18844 -- a default expression, we do the special preanalysis, since this
18845 -- expression does not freeze (see section "Handling of Default and
18846 -- Per-Object Expressions" in spec of package Sem).
18848 if Present (Expression (Discr)) then
18849 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
18853 if Nkind (N) = N_Formal_Type_Declaration then
18855 ("discriminant defaults not allowed for formal type",
18856 Expression (Discr));
18858 -- Flag an error for a tagged type with defaulted discriminants,
18859 -- excluding limited tagged types when compiling for Ada 2012
18860 -- (see AI05-0214).
18862 elsif Is_Tagged_Type (Current_Scope)
18863 and then (not Is_Limited_Type (Current_Scope)
18864 or else Ada_Version < Ada_2012)
18865 and then Comes_From_Source (N)
18867 -- Note: see similar test in Check_Or_Process_Discriminants, to
18868 -- handle the (illegal) case of the completion of an untagged
18869 -- view with discriminants with defaults by a tagged full view.
18870 -- We skip the check if Discr does not come from source, to
18871 -- account for the case of an untagged derived type providing
18872 -- defaults for a renamed discriminant from a private untagged
18873 -- ancestor with a tagged full view (ACATS B460006).
18875 if Ada_Version >= Ada_2012 then
18877 ("discriminants of nonlimited tagged type cannot have"
18879 Expression (Discr));
18882 ("discriminants of tagged type cannot have defaults",
18883 Expression (Discr));
18887 Default_Present := True;
18888 Append_Elmt (Expression (Discr), Elist);
18890 -- Tag the defining identifiers for the discriminants with
18891 -- their corresponding default expressions from the tree.
18893 Set_Discriminant_Default_Value
18894 (Defining_Identifier (Discr), Expression (Discr));
18897 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag
18898 -- gets set unless we can be sure that no range check is required.
18900 if (GNATprove_Mode or not Expander_Active)
18903 (Expression (Discr), Discr_Type, Assume_Valid => True)
18905 Set_Do_Range_Check (Expression (Discr));
18908 -- No default discriminant value given
18911 Default_Not_Present := True;
18914 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
18915 -- Discr_Type but with the null-exclusion attribute
18917 if Ada_Version >= Ada_2005 then
18919 -- Ada 2005 (AI-231): Static checks
18921 if Can_Never_Be_Null (Discr_Type) then
18922 Null_Exclusion_Static_Checks (Discr);
18924 elsif Is_Access_Type (Discr_Type)
18925 and then Null_Exclusion_Present (Discr)
18927 -- No need to check itypes because in their case this check
18928 -- was done at their point of creation
18930 and then not Is_Itype (Discr_Type)
18932 if Can_Never_Be_Null (Discr_Type) then
18934 ("`NOT NULL` not allowed (& already excludes null)",
18939 Set_Etype (Defining_Identifier (Discr),
18940 Create_Null_Excluding_Itype
18942 Related_Nod => Discr));
18944 -- Check for improper null exclusion if the type is otherwise
18945 -- legal for a discriminant.
18947 elsif Null_Exclusion_Present (Discr)
18948 and then Is_Discrete_Type (Discr_Type)
18951 ("null exclusion can only apply to an access type", Discr);
18954 -- Ada 2005 (AI-402): access discriminants of nonlimited types
18955 -- can't have defaults. Synchronized types, or types that are
18956 -- explicitly limited are fine, but special tests apply to derived
18957 -- types in generics: in a generic body we have to assume the
18958 -- worst, and therefore defaults are not allowed if the parent is
18959 -- a generic formal private type (see ACATS B370001).
18961 if Is_Access_Type (Discr_Type) and then Default_Present then
18962 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
18963 or else Is_Limited_Record (Current_Scope)
18964 or else Is_Concurrent_Type (Current_Scope)
18965 or else Is_Concurrent_Record_Type (Current_Scope)
18966 or else Ekind (Current_Scope) = E_Limited_Private_Type
18968 if not Is_Derived_Type (Current_Scope)
18969 or else not Is_Generic_Type (Etype (Current_Scope))
18970 or else not In_Package_Body (Scope (Etype (Current_Scope)))
18971 or else Limited_Present
18972 (Type_Definition (Parent (Current_Scope)))
18978 ("access discriminants of nonlimited types cannot "
18979 & "have defaults", Expression (Discr));
18982 elsif Present (Expression (Discr)) then
18984 ("(Ada 2005) access discriminants of nonlimited types "
18985 & "cannot have defaults", Expression (Discr));
18990 -- A discriminant cannot be effectively volatile. This check is only
18991 -- relevant when SPARK_Mode is on as it is not standard Ada legality
18992 -- rule (SPARK RM 7.1.3(6)).
18995 and then Is_Effectively_Volatile (Defining_Identifier (Discr))
18997 Error_Msg_N ("discriminant cannot be volatile", Discr);
19003 -- An element list consisting of the default expressions of the
19004 -- discriminants is constructed in the above loop and used to set
19005 -- the Discriminant_Constraint attribute for the type. If an object
19006 -- is declared of this (record or task) type without any explicit
19007 -- discriminant constraint given, this element list will form the
19008 -- actual parameters for the corresponding initialization procedure
19011 Set_Discriminant_Constraint (Current_Scope, Elist);
19012 Set_Stored_Constraint (Current_Scope, No_Elist);
19014 -- Default expressions must be provided either for all or for none
19015 -- of the discriminants of a discriminant part. (RM 3.7.1)
19017 if Default_Present and then Default_Not_Present then
19019 ("incomplete specification of defaults for discriminants", N);
19022 -- The use of the name of a discriminant is not allowed in default
19023 -- expressions of a discriminant part if the specification of the
19024 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
19026 -- To detect this, the discriminant names are entered initially with an
19027 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
19028 -- attempt to use a void entity (for example in an expression that is
19029 -- type-checked) produces the error message: premature usage. Now after
19030 -- completing the semantic analysis of the discriminant part, we can set
19031 -- the Ekind of all the discriminants appropriately.
19033 Discr := First (Discriminant_Specifications (N));
19034 Discr_Number := Uint_1;
19035 while Present (Discr) loop
19036 Id := Defining_Identifier (Discr);
19037 Set_Ekind (Id, E_Discriminant);
19038 Init_Component_Location (Id);
19040 Set_Discriminant_Number (Id, Discr_Number);
19042 -- Make sure this is always set, even in illegal programs
19044 Set_Corresponding_Discriminant (Id, Empty);
19046 -- Initialize the Original_Record_Component to the entity itself.
19047 -- Inherit_Components will propagate the right value to
19048 -- discriminants in derived record types.
19050 Set_Original_Record_Component (Id, Id);
19052 -- Create the discriminal for the discriminant
19054 Build_Discriminal (Id);
19057 Discr_Number := Discr_Number + 1;
19060 Set_Has_Discriminants (Current_Scope);
19061 end Process_Discriminants;
19063 -----------------------
19064 -- Process_Full_View --
19065 -----------------------
19067 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
19068 procedure Collect_Implemented_Interfaces
19070 Ifaces : Elist_Id);
19071 -- Ada 2005: Gather all the interfaces that Typ directly or
19072 -- inherently implements. Duplicate entries are not added to
19073 -- the list Ifaces.
19075 ------------------------------------
19076 -- Collect_Implemented_Interfaces --
19077 ------------------------------------
19079 procedure Collect_Implemented_Interfaces
19084 Iface_Elmt : Elmt_Id;
19087 -- Abstract interfaces are only associated with tagged record types
19089 if not Is_Tagged_Type (Typ) or else not Is_Record_Type (Typ) then
19093 -- Recursively climb to the ancestors
19095 if Etype (Typ) /= Typ
19097 -- Protect the frontend against wrong cyclic declarations like:
19099 -- type B is new A with private;
19100 -- type C is new A with private;
19102 -- type B is new C with null record;
19103 -- type C is new B with null record;
19105 and then Etype (Typ) /= Priv_T
19106 and then Etype (Typ) /= Full_T
19108 -- Keep separate the management of private type declarations
19110 if Ekind (Typ) = E_Record_Type_With_Private then
19112 -- Handle the following illegal usage:
19113 -- type Private_Type is tagged private;
19115 -- type Private_Type is new Type_Implementing_Iface;
19117 if Present (Full_View (Typ))
19118 and then Etype (Typ) /= Full_View (Typ)
19120 if Is_Interface (Etype (Typ)) then
19121 Append_Unique_Elmt (Etype (Typ), Ifaces);
19124 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
19127 -- Non-private types
19130 if Is_Interface (Etype (Typ)) then
19131 Append_Unique_Elmt (Etype (Typ), Ifaces);
19134 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
19138 -- Handle entities in the list of abstract interfaces
19140 if Present (Interfaces (Typ)) then
19141 Iface_Elmt := First_Elmt (Interfaces (Typ));
19142 while Present (Iface_Elmt) loop
19143 Iface := Node (Iface_Elmt);
19145 pragma Assert (Is_Interface (Iface));
19147 if not Contain_Interface (Iface, Ifaces) then
19148 Append_Elmt (Iface, Ifaces);
19149 Collect_Implemented_Interfaces (Iface, Ifaces);
19152 Next_Elmt (Iface_Elmt);
19155 end Collect_Implemented_Interfaces;
19159 Full_Indic : Node_Id;
19160 Full_Parent : Entity_Id;
19161 Priv_Parent : Entity_Id;
19163 -- Start of processing for Process_Full_View
19166 -- First some sanity checks that must be done after semantic
19167 -- decoration of the full view and thus cannot be placed with other
19168 -- similar checks in Find_Type_Name
19170 if not Is_Limited_Type (Priv_T)
19171 and then (Is_Limited_Type (Full_T)
19172 or else Is_Limited_Composite (Full_T))
19174 if In_Instance then
19178 ("completion of nonlimited type cannot be limited", Full_T);
19179 Explain_Limited_Type (Full_T, Full_T);
19182 elsif Is_Abstract_Type (Full_T)
19183 and then not Is_Abstract_Type (Priv_T)
19186 ("completion of nonabstract type cannot be abstract", Full_T);
19188 elsif Is_Tagged_Type (Priv_T)
19189 and then Is_Limited_Type (Priv_T)
19190 and then not Is_Limited_Type (Full_T)
19192 -- If pragma CPP_Class was applied to the private declaration
19193 -- propagate the limitedness to the full-view
19195 if Is_CPP_Class (Priv_T) then
19196 Set_Is_Limited_Record (Full_T);
19198 -- GNAT allow its own definition of Limited_Controlled to disobey
19199 -- this rule in order in ease the implementation. This test is safe
19200 -- because Root_Controlled is defined in a child of System that
19201 -- normal programs are not supposed to use.
19203 elsif Is_RTE (Etype (Full_T), RE_Root_Controlled) then
19204 Set_Is_Limited_Composite (Full_T);
19207 ("completion of limited tagged type must be limited", Full_T);
19210 elsif Is_Generic_Type (Priv_T) then
19211 Error_Msg_N ("generic type cannot have a completion", Full_T);
19214 -- Check that ancestor interfaces of private and full views are
19215 -- consistent. We omit this check for synchronized types because
19216 -- they are performed on the corresponding record type when frozen.
19218 if Ada_Version >= Ada_2005
19219 and then Is_Tagged_Type (Priv_T)
19220 and then Is_Tagged_Type (Full_T)
19221 and then not Is_Concurrent_Type (Full_T)
19225 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
19226 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
19229 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
19230 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
19232 -- Ada 2005 (AI-251): The partial view shall be a descendant of
19233 -- an interface type if and only if the full type is descendant
19234 -- of the interface type (AARM 7.3 (7.3/2)).
19236 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
19238 if Present (Iface) then
19240 ("interface in partial view& not implemented by full type "
19241 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
19244 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
19246 if Present (Iface) then
19248 ("interface & not implemented by partial view "
19249 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
19254 if Is_Tagged_Type (Priv_T)
19255 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19256 and then Is_Derived_Type (Full_T)
19258 Priv_Parent := Etype (Priv_T);
19260 -- The full view of a private extension may have been transformed
19261 -- into an unconstrained derived type declaration and a subtype
19262 -- declaration (see build_derived_record_type for details).
19264 if Nkind (N) = N_Subtype_Declaration then
19265 Full_Indic := Subtype_Indication (N);
19266 Full_Parent := Etype (Base_Type (Full_T));
19268 Full_Indic := Subtype_Indication (Type_Definition (N));
19269 Full_Parent := Etype (Full_T);
19272 -- Check that the parent type of the full type is a descendant of
19273 -- the ancestor subtype given in the private extension. If either
19274 -- entity has an Etype equal to Any_Type then we had some previous
19275 -- error situation [7.3(8)].
19277 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
19280 -- Ada 2005 (AI-251): Interfaces in the full type can be given in
19281 -- any order. Therefore we don't have to check that its parent must
19282 -- be a descendant of the parent of the private type declaration.
19284 elsif Is_Interface (Priv_Parent)
19285 and then Is_Interface (Full_Parent)
19289 -- Ada 2005 (AI-251): If the parent of the private type declaration
19290 -- is an interface there is no need to check that it is an ancestor
19291 -- of the associated full type declaration. The required tests for
19292 -- this case are performed by Build_Derived_Record_Type.
19294 elsif not Is_Interface (Base_Type (Priv_Parent))
19295 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
19298 ("parent of full type must descend from parent"
19299 & " of private extension", Full_Indic);
19301 -- First check a formal restriction, and then proceed with checking
19302 -- Ada rules. Since the formal restriction is not a serious error, we
19303 -- don't prevent further error detection for this check, hence the
19307 -- In formal mode, when completing a private extension the type
19308 -- named in the private part must be exactly the same as that
19309 -- named in the visible part.
19311 if Priv_Parent /= Full_Parent then
19312 Error_Msg_Name_1 := Chars (Priv_Parent);
19313 Check_SPARK_05_Restriction ("% expected", Full_Indic);
19316 -- Check the rules of 7.3(10): if the private extension inherits
19317 -- known discriminants, then the full type must also inherit those
19318 -- discriminants from the same (ancestor) type, and the parent
19319 -- subtype of the full type must be constrained if and only if
19320 -- the ancestor subtype of the private extension is constrained.
19322 if No (Discriminant_Specifications (Parent (Priv_T)))
19323 and then not Has_Unknown_Discriminants (Priv_T)
19324 and then Has_Discriminants (Base_Type (Priv_Parent))
19327 Priv_Indic : constant Node_Id :=
19328 Subtype_Indication (Parent (Priv_T));
19330 Priv_Constr : constant Boolean :=
19331 Is_Constrained (Priv_Parent)
19333 Nkind (Priv_Indic) = N_Subtype_Indication
19335 Is_Constrained (Entity (Priv_Indic));
19337 Full_Constr : constant Boolean :=
19338 Is_Constrained (Full_Parent)
19340 Nkind (Full_Indic) = N_Subtype_Indication
19342 Is_Constrained (Entity (Full_Indic));
19344 Priv_Discr : Entity_Id;
19345 Full_Discr : Entity_Id;
19348 Priv_Discr := First_Discriminant (Priv_Parent);
19349 Full_Discr := First_Discriminant (Full_Parent);
19350 while Present (Priv_Discr) and then Present (Full_Discr) loop
19351 if Original_Record_Component (Priv_Discr) =
19352 Original_Record_Component (Full_Discr)
19354 Corresponding_Discriminant (Priv_Discr) =
19355 Corresponding_Discriminant (Full_Discr)
19362 Next_Discriminant (Priv_Discr);
19363 Next_Discriminant (Full_Discr);
19366 if Present (Priv_Discr) or else Present (Full_Discr) then
19368 ("full view must inherit discriminants of the parent"
19369 & " type used in the private extension", Full_Indic);
19371 elsif Priv_Constr and then not Full_Constr then
19373 ("parent subtype of full type must be constrained",
19376 elsif Full_Constr and then not Priv_Constr then
19378 ("parent subtype of full type must be unconstrained",
19383 -- Check the rules of 7.3(12): if a partial view has neither
19384 -- known or unknown discriminants, then the full type
19385 -- declaration shall define a definite subtype.
19387 elsif not Has_Unknown_Discriminants (Priv_T)
19388 and then not Has_Discriminants (Priv_T)
19389 and then not Is_Constrained (Full_T)
19392 ("full view must define a constrained type if partial view"
19393 & " has no discriminants", Full_T);
19396 -- ??????? Do we implement the following properly ?????
19397 -- If the ancestor subtype of a private extension has constrained
19398 -- discriminants, then the parent subtype of the full view shall
19399 -- impose a statically matching constraint on those discriminants
19404 -- For untagged types, verify that a type without discriminants is
19405 -- not completed with an unconstrained type. A separate error message
19406 -- is produced if the full type has defaulted discriminants.
19408 if not Is_Indefinite_Subtype (Priv_T)
19409 and then Is_Indefinite_Subtype (Full_T)
19411 Error_Msg_Sloc := Sloc (Parent (Priv_T));
19413 ("full view of& not compatible with declaration#",
19416 if not Is_Tagged_Type (Full_T) then
19418 ("\one is constrained, the other unconstrained", Full_T);
19423 -- AI-419: verify that the use of "limited" is consistent
19426 Orig_Decl : constant Node_Id := Original_Node (N);
19429 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19430 and then not Limited_Present (Parent (Priv_T))
19431 and then not Synchronized_Present (Parent (Priv_T))
19432 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
19434 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
19435 and then Limited_Present (Type_Definition (Orig_Decl))
19438 ("full view of non-limited extension cannot be limited", N);
19442 -- Ada 2005 (AI-443): A synchronized private extension must be
19443 -- completed by a task or protected type.
19445 if Ada_Version >= Ada_2005
19446 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19447 and then Synchronized_Present (Parent (Priv_T))
19448 and then not Is_Concurrent_Type (Full_T)
19450 Error_Msg_N ("full view of synchronized extension must " &
19451 "be synchronized type", N);
19454 -- Ada 2005 AI-363: if the full view has discriminants with
19455 -- defaults, it is illegal to declare constrained access subtypes
19456 -- whose designated type is the current type. This allows objects
19457 -- of the type that are declared in the heap to be unconstrained.
19459 if not Has_Unknown_Discriminants (Priv_T)
19460 and then not Has_Discriminants (Priv_T)
19461 and then Has_Discriminants (Full_T)
19463 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
19465 Set_Has_Constrained_Partial_View (Full_T);
19466 Set_Has_Constrained_Partial_View (Priv_T);
19469 -- Create a full declaration for all its subtypes recorded in
19470 -- Private_Dependents and swap them similarly to the base type. These
19471 -- are subtypes that have been define before the full declaration of
19472 -- the private type. We also swap the entry in Private_Dependents list
19473 -- so we can properly restore the private view on exit from the scope.
19476 Priv_Elmt : Elmt_Id;
19477 Priv_Scop : Entity_Id;
19482 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
19483 while Present (Priv_Elmt) loop
19484 Priv := Node (Priv_Elmt);
19485 Priv_Scop := Scope (Priv);
19487 if Ekind_In (Priv, E_Private_Subtype,
19488 E_Limited_Private_Subtype,
19489 E_Record_Subtype_With_Private)
19491 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
19492 Set_Is_Itype (Full);
19493 Set_Parent (Full, Parent (Priv));
19494 Set_Associated_Node_For_Itype (Full, N);
19496 -- Now we need to complete the private subtype, but since the
19497 -- base type has already been swapped, we must also swap the
19498 -- subtypes (and thus, reverse the arguments in the call to
19499 -- Complete_Private_Subtype). Also note that we may need to
19500 -- re-establish the scope of the private subtype.
19502 Copy_And_Swap (Priv, Full);
19504 if not In_Open_Scopes (Priv_Scop) then
19505 Push_Scope (Priv_Scop);
19508 -- Reset Priv_Scop to Empty to indicate no scope was pushed
19510 Priv_Scop := Empty;
19513 Complete_Private_Subtype (Full, Priv, Full_T, N);
19515 if Present (Priv_Scop) then
19519 Replace_Elmt (Priv_Elmt, Full);
19522 Next_Elmt (Priv_Elmt);
19526 -- If the private view was tagged, copy the new primitive operations
19527 -- from the private view to the full view.
19529 if Is_Tagged_Type (Full_T) then
19531 Disp_Typ : Entity_Id;
19532 Full_List : Elist_Id;
19534 Prim_Elmt : Elmt_Id;
19535 Priv_List : Elist_Id;
19539 L : Elist_Id) return Boolean;
19540 -- Determine whether list L contains element E
19548 L : Elist_Id) return Boolean
19550 List_Elmt : Elmt_Id;
19553 List_Elmt := First_Elmt (L);
19554 while Present (List_Elmt) loop
19555 if Node (List_Elmt) = E then
19559 Next_Elmt (List_Elmt);
19565 -- Start of processing
19568 if Is_Tagged_Type (Priv_T) then
19569 Priv_List := Primitive_Operations (Priv_T);
19570 Prim_Elmt := First_Elmt (Priv_List);
19572 -- In the case of a concurrent type completing a private tagged
19573 -- type, primitives may have been declared in between the two
19574 -- views. These subprograms need to be wrapped the same way
19575 -- entries and protected procedures are handled because they
19576 -- cannot be directly shared by the two views.
19578 if Is_Concurrent_Type (Full_T) then
19580 Conc_Typ : constant Entity_Id :=
19581 Corresponding_Record_Type (Full_T);
19582 Curr_Nod : Node_Id := Parent (Conc_Typ);
19583 Wrap_Spec : Node_Id;
19586 while Present (Prim_Elmt) loop
19587 Prim := Node (Prim_Elmt);
19589 if Comes_From_Source (Prim)
19590 and then not Is_Abstract_Subprogram (Prim)
19593 Make_Subprogram_Declaration (Sloc (Prim),
19597 Obj_Typ => Conc_Typ,
19599 Parameter_Specifications (
19602 Insert_After (Curr_Nod, Wrap_Spec);
19603 Curr_Nod := Wrap_Spec;
19605 Analyze (Wrap_Spec);
19608 Next_Elmt (Prim_Elmt);
19614 -- For non-concurrent types, transfer explicit primitives, but
19615 -- omit those inherited from the parent of the private view
19616 -- since they will be re-inherited later on.
19619 Full_List := Primitive_Operations (Full_T);
19621 while Present (Prim_Elmt) loop
19622 Prim := Node (Prim_Elmt);
19624 if Comes_From_Source (Prim)
19625 and then not Contains (Prim, Full_List)
19627 Append_Elmt (Prim, Full_List);
19630 Next_Elmt (Prim_Elmt);
19634 -- Untagged private view
19637 Full_List := Primitive_Operations (Full_T);
19639 -- In this case the partial view is untagged, so here we locate
19640 -- all of the earlier primitives that need to be treated as
19641 -- dispatching (those that appear between the two views). Note
19642 -- that these additional operations must all be new operations
19643 -- (any earlier operations that override inherited operations
19644 -- of the full view will already have been inserted in the
19645 -- primitives list, marked by Check_Operation_From_Private_View
19646 -- as dispatching. Note that implicit "/=" operators are
19647 -- excluded from being added to the primitives list since they
19648 -- shouldn't be treated as dispatching (tagged "/=" is handled
19651 Prim := Next_Entity (Full_T);
19652 while Present (Prim) and then Prim /= Priv_T loop
19653 if Ekind_In (Prim, E_Procedure, E_Function) then
19654 Disp_Typ := Find_Dispatching_Type (Prim);
19656 if Disp_Typ = Full_T
19657 and then (Chars (Prim) /= Name_Op_Ne
19658 or else Comes_From_Source (Prim))
19660 Check_Controlling_Formals (Full_T, Prim);
19662 if not Is_Dispatching_Operation (Prim) then
19663 Append_Elmt (Prim, Full_List);
19664 Set_Is_Dispatching_Operation (Prim, True);
19665 Set_DT_Position (Prim, No_Uint);
19668 elsif Is_Dispatching_Operation (Prim)
19669 and then Disp_Typ /= Full_T
19672 -- Verify that it is not otherwise controlled by a
19673 -- formal or a return value of type T.
19675 Check_Controlling_Formals (Disp_Typ, Prim);
19679 Next_Entity (Prim);
19683 -- For the tagged case, the two views can share the same primitive
19684 -- operations list and the same class-wide type. Update attributes
19685 -- of the class-wide type which depend on the full declaration.
19687 if Is_Tagged_Type (Priv_T) then
19688 Set_Direct_Primitive_Operations (Priv_T, Full_List);
19689 Set_Class_Wide_Type
19690 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
19692 Set_Has_Task (Class_Wide_Type (Priv_T), Has_Task (Full_T));
19694 (Class_Wide_Type (Priv_T), Has_Protected (Full_T));
19699 -- Ada 2005 AI 161: Check preelaborable initialization consistency
19701 if Known_To_Have_Preelab_Init (Priv_T) then
19703 -- Case where there is a pragma Preelaborable_Initialization. We
19704 -- always allow this in predefined units, which is cheating a bit,
19705 -- but it means we don't have to struggle to meet the requirements in
19706 -- the RM for having Preelaborable Initialization. Otherwise we
19707 -- require that the type meets the RM rules. But we can't check that
19708 -- yet, because of the rule about overriding Initialize, so we simply
19709 -- set a flag that will be checked at freeze time.
19711 if not In_Predefined_Unit (Full_T) then
19712 Set_Must_Have_Preelab_Init (Full_T);
19716 -- If pragma CPP_Class was applied to the private type declaration,
19717 -- propagate it now to the full type declaration.
19719 if Is_CPP_Class (Priv_T) then
19720 Set_Is_CPP_Class (Full_T);
19721 Set_Convention (Full_T, Convention_CPP);
19723 -- Check that components of imported CPP types do not have default
19726 Check_CPP_Type_Has_No_Defaults (Full_T);
19729 -- If the private view has user specified stream attributes, then so has
19732 -- Why the test, how could these flags be already set in Full_T ???
19734 if Has_Specified_Stream_Read (Priv_T) then
19735 Set_Has_Specified_Stream_Read (Full_T);
19738 if Has_Specified_Stream_Write (Priv_T) then
19739 Set_Has_Specified_Stream_Write (Full_T);
19742 if Has_Specified_Stream_Input (Priv_T) then
19743 Set_Has_Specified_Stream_Input (Full_T);
19746 if Has_Specified_Stream_Output (Priv_T) then
19747 Set_Has_Specified_Stream_Output (Full_T);
19750 -- Propagate the attributes related to pragma Default_Initial_Condition
19751 -- from the private to the full view. Note that both flags are mutually
19754 if Has_Default_Init_Cond (Priv_T)
19755 or else Has_Inherited_Default_Init_Cond (Priv_T)
19757 Propagate_Default_Init_Cond_Attributes
19758 (From_Typ => Priv_T,
19760 Private_To_Full_View => True);
19762 -- In the case where the full view is derived from another private type,
19763 -- the attributes related to pragma Default_Initial_Condition must be
19764 -- propagated from the full to the private view to maintain consistency
19768 -- type Parent_Typ is private
19769 -- with Default_Initial_Condition ...;
19771 -- type Parent_Typ is ...;
19774 -- with Pack; use Pack;
19775 -- package Pack_2 is
19776 -- type Deriv_Typ is private; -- must inherit
19778 -- type Deriv_Typ is new Parent_Typ; -- must inherit
19781 elsif Has_Default_Init_Cond (Full_T)
19782 or else Has_Inherited_Default_Init_Cond (Full_T)
19784 Propagate_Default_Init_Cond_Attributes
19785 (From_Typ => Full_T,
19787 Private_To_Full_View => True);
19790 -- Propagate the attributes related to pragma Ghost from the private to
19793 if Is_Ghost_Entity (Priv_T) then
19794 Set_Is_Ghost_Entity (Full_T);
19796 -- The Ghost policy in effect at the point of declaration and at the
19797 -- point of completion must match (SPARK RM 6.9(15)).
19799 Check_Ghost_Completion (Priv_T, Full_T);
19801 -- In the case where the private view of a tagged type lacks a parent
19802 -- type and is subject to pragma Ghost, ensure that the parent type
19803 -- specified by the full view is also Ghost (SPARK RM 6.9(9)).
19805 if Is_Derived_Type (Full_T) then
19806 Check_Ghost_Derivation (Full_T);
19810 -- Propagate invariants to full type
19812 if Has_Invariants (Priv_T) then
19813 Set_Has_Invariants (Full_T);
19814 Set_Invariant_Procedure (Full_T, Invariant_Procedure (Priv_T));
19817 if Has_Inheritable_Invariants (Priv_T) then
19818 Set_Has_Inheritable_Invariants (Full_T);
19821 -- Propagate predicates to full type, and predicate function if already
19822 -- defined. It is not clear that this can actually happen? the partial
19823 -- view cannot be frozen yet, and the predicate function has not been
19824 -- built. Still it is a cheap check and seems safer to make it.
19826 if Has_Predicates (Priv_T) then
19827 if Present (Predicate_Function (Priv_T)) then
19828 Set_Predicate_Function (Full_T, Predicate_Function (Priv_T));
19831 Set_Has_Predicates (Full_T);
19833 end Process_Full_View;
19835 -----------------------------------
19836 -- Process_Incomplete_Dependents --
19837 -----------------------------------
19839 procedure Process_Incomplete_Dependents
19841 Full_T : Entity_Id;
19844 Inc_Elmt : Elmt_Id;
19845 Priv_Dep : Entity_Id;
19846 New_Subt : Entity_Id;
19848 Disc_Constraint : Elist_Id;
19851 if No (Private_Dependents (Inc_T)) then
19855 -- Itypes that may be generated by the completion of an incomplete
19856 -- subtype are not used by the back-end and not attached to the tree.
19857 -- They are created only for constraint-checking purposes.
19859 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
19860 while Present (Inc_Elmt) loop
19861 Priv_Dep := Node (Inc_Elmt);
19863 if Ekind (Priv_Dep) = E_Subprogram_Type then
19865 -- An Access_To_Subprogram type may have a return type or a
19866 -- parameter type that is incomplete. Replace with the full view.
19868 if Etype (Priv_Dep) = Inc_T then
19869 Set_Etype (Priv_Dep, Full_T);
19873 Formal : Entity_Id;
19876 Formal := First_Formal (Priv_Dep);
19877 while Present (Formal) loop
19878 if Etype (Formal) = Inc_T then
19879 Set_Etype (Formal, Full_T);
19882 Next_Formal (Formal);
19886 elsif Is_Overloadable (Priv_Dep) then
19888 -- If a subprogram in the incomplete dependents list is primitive
19889 -- for a tagged full type then mark it as a dispatching operation,
19890 -- check whether it overrides an inherited subprogram, and check
19891 -- restrictions on its controlling formals. Note that a protected
19892 -- operation is never dispatching: only its wrapper operation
19893 -- (which has convention Ada) is.
19895 if Is_Tagged_Type (Full_T)
19896 and then Is_Primitive (Priv_Dep)
19897 and then Convention (Priv_Dep) /= Convention_Protected
19899 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
19900 Set_Is_Dispatching_Operation (Priv_Dep);
19901 Check_Controlling_Formals (Full_T, Priv_Dep);
19904 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
19906 -- Can happen during processing of a body before the completion
19907 -- of a TA type. Ignore, because spec is also on dependent list.
19911 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
19912 -- corresponding subtype of the full view.
19914 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype then
19915 Set_Subtype_Indication
19916 (Parent (Priv_Dep), New_Occurrence_Of (Full_T, Sloc (Priv_Dep)));
19917 Set_Etype (Priv_Dep, Full_T);
19918 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
19919 Set_Analyzed (Parent (Priv_Dep), False);
19921 -- Reanalyze the declaration, suppressing the call to
19922 -- Enter_Name to avoid duplicate names.
19924 Analyze_Subtype_Declaration
19925 (N => Parent (Priv_Dep),
19928 -- Dependent is a subtype
19931 -- We build a new subtype indication using the full view of the
19932 -- incomplete parent. The discriminant constraints have been
19933 -- elaborated already at the point of the subtype declaration.
19935 New_Subt := Create_Itype (E_Void, N);
19937 if Has_Discriminants (Full_T) then
19938 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
19940 Disc_Constraint := No_Elist;
19943 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
19944 Set_Full_View (Priv_Dep, New_Subt);
19947 Next_Elmt (Inc_Elmt);
19949 end Process_Incomplete_Dependents;
19951 --------------------------------
19952 -- Process_Range_Expr_In_Decl --
19953 --------------------------------
19955 procedure Process_Range_Expr_In_Decl
19958 Subtyp : Entity_Id := Empty;
19959 Check_List : List_Id := Empty_List;
19960 R_Check_Off : Boolean := False;
19961 In_Iter_Schm : Boolean := False)
19964 R_Checks : Check_Result;
19965 Insert_Node : Node_Id;
19966 Def_Id : Entity_Id;
19969 Analyze_And_Resolve (R, Base_Type (T));
19971 if Nkind (R) = N_Range then
19973 -- In SPARK, all ranges should be static, with the exception of the
19974 -- discrete type definition of a loop parameter specification.
19976 if not In_Iter_Schm
19977 and then not Is_OK_Static_Range (R)
19979 Check_SPARK_05_Restriction ("range should be static", R);
19982 Lo := Low_Bound (R);
19983 Hi := High_Bound (R);
19985 -- Validity checks on the range of a quantified expression are
19986 -- delayed until the construct is transformed into a loop.
19988 if Nkind (Parent (R)) = N_Loop_Parameter_Specification
19989 and then Nkind (Parent (Parent (R))) = N_Quantified_Expression
19993 -- We need to ensure validity of the bounds here, because if we
19994 -- go ahead and do the expansion, then the expanded code will get
19995 -- analyzed with range checks suppressed and we miss the check.
19997 -- WARNING: The capture of the range bounds with xxx_FIRST/_LAST and
19998 -- the temporaries generated by routine Remove_Side_Effects by means
19999 -- of validity checks must use the same names. When a range appears
20000 -- in the parent of a generic, the range is processed with checks
20001 -- disabled as part of the generic context and with checks enabled
20002 -- for code generation purposes. This leads to link issues as the
20003 -- generic contains references to xxx_FIRST/_LAST, but the inlined
20004 -- template sees the temporaries generated by Remove_Side_Effects.
20007 Validity_Check_Range (R, Subtyp);
20010 -- If there were errors in the declaration, try and patch up some
20011 -- common mistakes in the bounds. The cases handled are literals
20012 -- which are Integer where the expected type is Real and vice versa.
20013 -- These corrections allow the compilation process to proceed further
20014 -- along since some basic assumptions of the format of the bounds
20017 if Etype (R) = Any_Type then
20018 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
20020 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
20022 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
20024 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
20026 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
20028 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
20030 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
20032 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
20039 -- If the bounds of the range have been mistakenly given as string
20040 -- literals (perhaps in place of character literals), then an error
20041 -- has already been reported, but we rewrite the string literal as a
20042 -- bound of the range's type to avoid blowups in later processing
20043 -- that looks at static values.
20045 if Nkind (Lo) = N_String_Literal then
20047 Make_Attribute_Reference (Sloc (Lo),
20048 Prefix => New_Occurrence_Of (T, Sloc (Lo)),
20049 Attribute_Name => Name_First));
20050 Analyze_And_Resolve (Lo);
20053 if Nkind (Hi) = N_String_Literal then
20055 Make_Attribute_Reference (Sloc (Hi),
20056 Prefix => New_Occurrence_Of (T, Sloc (Hi)),
20057 Attribute_Name => Name_First));
20058 Analyze_And_Resolve (Hi);
20061 -- If bounds aren't scalar at this point then exit, avoiding
20062 -- problems with further processing of the range in this procedure.
20064 if not Is_Scalar_Type (Etype (Lo)) then
20068 -- Resolve (actually Sem_Eval) has checked that the bounds are in
20069 -- then range of the base type. Here we check whether the bounds
20070 -- are in the range of the subtype itself. Note that if the bounds
20071 -- represent the null range the Constraint_Error exception should
20074 -- ??? The following code should be cleaned up as follows
20076 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
20077 -- is done in the call to Range_Check (R, T); below
20079 -- 2. The use of R_Check_Off should be investigated and possibly
20080 -- removed, this would clean up things a bit.
20082 if Is_Null_Range (Lo, Hi) then
20086 -- Capture values of bounds and generate temporaries for them
20087 -- if needed, before applying checks, since checks may cause
20088 -- duplication of the expression without forcing evaluation.
20090 -- The forced evaluation removes side effects from expressions,
20091 -- which should occur also in GNATprove mode. Otherwise, we end up
20092 -- with unexpected insertions of actions at places where this is
20093 -- not supposed to occur, e.g. on default parameters of a call.
20095 if Expander_Active or GNATprove_Mode then
20097 -- If no subtype name, then just call Force_Evaluation to
20098 -- create declarations as needed to deal with side effects.
20099 -- Also ignore calls from within a record type, where we
20100 -- have possible scoping issues.
20102 if No (Subtyp) or else Is_Record_Type (Current_Scope) then
20103 Force_Evaluation (Lo);
20104 Force_Evaluation (Hi);
20106 -- If a subtype is given, then we capture the bounds if they
20107 -- are not known at compile time, using constant identifiers
20108 -- xxx_FIRST and xxx_LAST where xxx is the name of the subtype.
20110 -- Note: we do this transformation even if expansion is not
20111 -- active, and in particular we do it in GNATprove_Mode since
20112 -- the transformation is in general required to ensure that the
20113 -- resulting tree has proper Ada semantics.
20115 -- Historical note: We used to just do Force_Evaluation calls
20116 -- in all cases, but it is better to capture the bounds with
20117 -- proper non-serialized names, since these will be accessed
20118 -- from other units, and hence may be public, and also we can
20119 -- then expand 'First and 'Last references to be references to
20120 -- these special names.
20123 if not Compile_Time_Known_Value (Lo)
20125 -- No need to capture bounds if they already are
20126 -- references to constants.
20128 and then not (Is_Entity_Name (Lo)
20129 and then Is_Constant_Object (Entity (Lo)))
20132 Loc : constant Source_Ptr := Sloc (Lo);
20133 Lov : constant Entity_Id :=
20134 Make_Defining_Identifier (Loc,
20136 New_External_Name (Chars (Subtyp), "_FIRST"));
20139 Make_Object_Declaration (Loc,
20140 Defining_Identifier => Lov,
20141 Object_Definition =>
20142 New_Occurrence_Of (Base_Type (T), Loc),
20143 Constant_Present => True,
20144 Expression => Relocate_Node (Lo)));
20145 Rewrite (Lo, New_Occurrence_Of (Lov, Loc));
20149 if not Compile_Time_Known_Value (Hi)
20150 and then not (Is_Entity_Name (Hi)
20151 and then Is_Constant_Object (Entity (Hi)))
20154 Loc : constant Source_Ptr := Sloc (Hi);
20155 Hiv : constant Entity_Id :=
20156 Make_Defining_Identifier (Loc,
20158 New_External_Name (Chars (Subtyp), "_LAST"));
20161 Make_Object_Declaration (Loc,
20162 Defining_Identifier => Hiv,
20163 Object_Definition =>
20164 New_Occurrence_Of (Base_Type (T), Loc),
20165 Constant_Present => True,
20166 Expression => Relocate_Node (Hi)));
20167 Rewrite (Hi, New_Occurrence_Of (Hiv, Loc));
20173 -- We use a flag here instead of suppressing checks on the
20174 -- type because the type we check against isn't necessarily
20175 -- the place where we put the check.
20177 if not R_Check_Off then
20178 R_Checks := Get_Range_Checks (R, T);
20180 -- Look up tree to find an appropriate insertion point. We
20181 -- can't just use insert_actions because later processing
20182 -- depends on the insertion node. Prior to Ada 2012 the
20183 -- insertion point could only be a declaration or a loop, but
20184 -- quantified expressions can appear within any context in an
20185 -- expression, and the insertion point can be any statement,
20186 -- pragma, or declaration.
20188 Insert_Node := Parent (R);
20189 while Present (Insert_Node) loop
20191 Nkind (Insert_Node) in N_Declaration
20194 (Insert_Node, N_Component_Declaration,
20195 N_Loop_Parameter_Specification,
20196 N_Function_Specification,
20197 N_Procedure_Specification);
20199 exit when Nkind (Insert_Node) in N_Later_Decl_Item
20200 or else Nkind (Insert_Node) in
20201 N_Statement_Other_Than_Procedure_Call
20202 or else Nkind_In (Insert_Node, N_Procedure_Call_Statement,
20205 Insert_Node := Parent (Insert_Node);
20208 -- Why would Type_Decl not be present??? Without this test,
20209 -- short regression tests fail.
20211 if Present (Insert_Node) then
20213 -- Case of loop statement. Verify that the range is part
20214 -- of the subtype indication of the iteration scheme.
20216 if Nkind (Insert_Node) = N_Loop_Statement then
20221 Indic := Parent (R);
20222 while Present (Indic)
20223 and then Nkind (Indic) /= N_Subtype_Indication
20225 Indic := Parent (Indic);
20228 if Present (Indic) then
20229 Def_Id := Etype (Subtype_Mark (Indic));
20231 Insert_Range_Checks
20235 Sloc (Insert_Node),
20237 Do_Before => True);
20241 -- Insertion before a declaration. If the declaration
20242 -- includes discriminants, the list of applicable checks
20243 -- is given by the caller.
20245 elsif Nkind (Insert_Node) in N_Declaration then
20246 Def_Id := Defining_Identifier (Insert_Node);
20248 if (Ekind (Def_Id) = E_Record_Type
20249 and then Depends_On_Discriminant (R))
20251 (Ekind (Def_Id) = E_Protected_Type
20252 and then Has_Discriminants (Def_Id))
20254 Append_Range_Checks
20256 Check_List, Def_Id, Sloc (Insert_Node), R);
20259 Insert_Range_Checks
20261 Insert_Node, Def_Id, Sloc (Insert_Node), R);
20265 -- Insertion before a statement. Range appears in the
20266 -- context of a quantified expression. Insertion will
20267 -- take place when expression is expanded.
20276 -- Case of other than an explicit N_Range node
20278 -- The forced evaluation removes side effects from expressions, which
20279 -- should occur also in GNATprove mode. Otherwise, we end up with
20280 -- unexpected insertions of actions at places where this is not
20281 -- supposed to occur, e.g. on default parameters of a call.
20283 elsif Expander_Active or GNATprove_Mode then
20284 Get_Index_Bounds (R, Lo, Hi);
20285 Force_Evaluation (Lo);
20286 Force_Evaluation (Hi);
20288 end Process_Range_Expr_In_Decl;
20290 --------------------------------------
20291 -- Process_Real_Range_Specification --
20292 --------------------------------------
20294 procedure Process_Real_Range_Specification (Def : Node_Id) is
20295 Spec : constant Node_Id := Real_Range_Specification (Def);
20298 Err : Boolean := False;
20300 procedure Analyze_Bound (N : Node_Id);
20301 -- Analyze and check one bound
20303 -------------------
20304 -- Analyze_Bound --
20305 -------------------
20307 procedure Analyze_Bound (N : Node_Id) is
20309 Analyze_And_Resolve (N, Any_Real);
20311 if not Is_OK_Static_Expression (N) then
20312 Flag_Non_Static_Expr
20313 ("bound in real type definition is not static!", N);
20318 -- Start of processing for Process_Real_Range_Specification
20321 if Present (Spec) then
20322 Lo := Low_Bound (Spec);
20323 Hi := High_Bound (Spec);
20324 Analyze_Bound (Lo);
20325 Analyze_Bound (Hi);
20327 -- If error, clear away junk range specification
20330 Set_Real_Range_Specification (Def, Empty);
20333 end Process_Real_Range_Specification;
20335 ---------------------
20336 -- Process_Subtype --
20337 ---------------------
20339 function Process_Subtype
20341 Related_Nod : Node_Id;
20342 Related_Id : Entity_Id := Empty;
20343 Suffix : Character := ' ') return Entity_Id
20346 Def_Id : Entity_Id;
20347 Error_Node : Node_Id;
20348 Full_View_Id : Entity_Id;
20349 Subtype_Mark_Id : Entity_Id;
20351 May_Have_Null_Exclusion : Boolean;
20353 procedure Check_Incomplete (T : Entity_Id);
20354 -- Called to verify that an incomplete type is not used prematurely
20356 ----------------------
20357 -- Check_Incomplete --
20358 ----------------------
20360 procedure Check_Incomplete (T : Entity_Id) is
20362 -- Ada 2005 (AI-412): Incomplete subtypes are legal
20364 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
20366 not (Ada_Version >= Ada_2005
20368 (Nkind (Parent (T)) = N_Subtype_Declaration
20369 or else (Nkind (Parent (T)) = N_Subtype_Indication
20370 and then Nkind (Parent (Parent (T))) =
20371 N_Subtype_Declaration)))
20373 Error_Msg_N ("invalid use of type before its full declaration", T);
20375 end Check_Incomplete;
20377 -- Start of processing for Process_Subtype
20380 -- Case of no constraints present
20382 if Nkind (S) /= N_Subtype_Indication then
20384 Check_Incomplete (S);
20387 -- Ada 2005 (AI-231): Static check
20389 if Ada_Version >= Ada_2005
20390 and then Present (P)
20391 and then Null_Exclusion_Present (P)
20392 and then Nkind (P) /= N_Access_To_Object_Definition
20393 and then not Is_Access_Type (Entity (S))
20395 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
20398 -- The following is ugly, can't we have a range or even a flag???
20400 May_Have_Null_Exclusion :=
20401 Nkind_In (P, N_Access_Definition,
20402 N_Access_Function_Definition,
20403 N_Access_Procedure_Definition,
20404 N_Access_To_Object_Definition,
20406 N_Component_Definition)
20408 Nkind_In (P, N_Derived_Type_Definition,
20409 N_Discriminant_Specification,
20410 N_Formal_Object_Declaration,
20411 N_Object_Declaration,
20412 N_Object_Renaming_Declaration,
20413 N_Parameter_Specification,
20414 N_Subtype_Declaration);
20416 -- Create an Itype that is a duplicate of Entity (S) but with the
20417 -- null-exclusion attribute.
20419 if May_Have_Null_Exclusion
20420 and then Is_Access_Type (Entity (S))
20421 and then Null_Exclusion_Present (P)
20423 -- No need to check the case of an access to object definition.
20424 -- It is correct to define double not-null pointers.
20427 -- type Not_Null_Int_Ptr is not null access Integer;
20428 -- type Acc is not null access Not_Null_Int_Ptr;
20430 and then Nkind (P) /= N_Access_To_Object_Definition
20432 if Can_Never_Be_Null (Entity (S)) then
20433 case Nkind (Related_Nod) is
20434 when N_Full_Type_Declaration =>
20435 if Nkind (Type_Definition (Related_Nod))
20436 in N_Array_Type_Definition
20440 (Component_Definition
20441 (Type_Definition (Related_Nod)));
20444 Subtype_Indication (Type_Definition (Related_Nod));
20447 when N_Subtype_Declaration =>
20448 Error_Node := Subtype_Indication (Related_Nod);
20450 when N_Object_Declaration =>
20451 Error_Node := Object_Definition (Related_Nod);
20453 when N_Component_Declaration =>
20455 Subtype_Indication (Component_Definition (Related_Nod));
20457 when N_Allocator =>
20458 Error_Node := Expression (Related_Nod);
20461 pragma Assert (False);
20462 Error_Node := Related_Nod;
20466 ("`NOT NULL` not allowed (& already excludes null)",
20472 Create_Null_Excluding_Itype
20474 Related_Nod => P));
20475 Set_Entity (S, Etype (S));
20480 -- Case of constraint present, so that we have an N_Subtype_Indication
20481 -- node (this node is created only if constraints are present).
20484 Find_Type (Subtype_Mark (S));
20486 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
20488 (Nkind (Parent (S)) = N_Subtype_Declaration
20489 and then Is_Itype (Defining_Identifier (Parent (S))))
20491 Check_Incomplete (Subtype_Mark (S));
20495 Subtype_Mark_Id := Entity (Subtype_Mark (S));
20497 -- Explicit subtype declaration case
20499 if Nkind (P) = N_Subtype_Declaration then
20500 Def_Id := Defining_Identifier (P);
20502 -- Explicit derived type definition case
20504 elsif Nkind (P) = N_Derived_Type_Definition then
20505 Def_Id := Defining_Identifier (Parent (P));
20507 -- Implicit case, the Def_Id must be created as an implicit type.
20508 -- The one exception arises in the case of concurrent types, array
20509 -- and access types, where other subsidiary implicit types may be
20510 -- created and must appear before the main implicit type. In these
20511 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
20512 -- has not yet been called to create Def_Id.
20515 if Is_Array_Type (Subtype_Mark_Id)
20516 or else Is_Concurrent_Type (Subtype_Mark_Id)
20517 or else Is_Access_Type (Subtype_Mark_Id)
20521 -- For the other cases, we create a new unattached Itype,
20522 -- and set the indication to ensure it gets attached later.
20526 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
20530 -- If the kind of constraint is invalid for this kind of type,
20531 -- then give an error, and then pretend no constraint was given.
20533 if not Is_Valid_Constraint_Kind
20534 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
20537 ("incorrect constraint for this kind of type", Constraint (S));
20539 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
20541 -- Set Ekind of orphan itype, to prevent cascaded errors
20543 if Present (Def_Id) then
20544 Set_Ekind (Def_Id, Ekind (Any_Type));
20547 -- Make recursive call, having got rid of the bogus constraint
20549 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
20552 -- Remaining processing depends on type. Select on Base_Type kind to
20553 -- ensure getting to the concrete type kind in the case of a private
20554 -- subtype (needed when only doing semantic analysis).
20556 case Ekind (Base_Type (Subtype_Mark_Id)) is
20557 when Access_Kind =>
20559 -- If this is a constraint on a class-wide type, discard it.
20560 -- There is currently no way to express a partial discriminant
20561 -- constraint on a type with unknown discriminants. This is
20562 -- a pathology that the ACATS wisely decides not to test.
20564 if Is_Class_Wide_Type (Designated_Type (Subtype_Mark_Id)) then
20565 if Comes_From_Source (S) then
20567 ("constraint on class-wide type ignored??",
20571 if Nkind (P) = N_Subtype_Declaration then
20572 Set_Subtype_Indication (P,
20573 New_Occurrence_Of (Subtype_Mark_Id, Sloc (S)));
20576 return Subtype_Mark_Id;
20579 Constrain_Access (Def_Id, S, Related_Nod);
20582 and then Is_Itype (Designated_Type (Def_Id))
20583 and then Nkind (Related_Nod) = N_Subtype_Declaration
20584 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
20586 Build_Itype_Reference
20587 (Designated_Type (Def_Id), Related_Nod);
20591 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
20593 when Decimal_Fixed_Point_Kind =>
20594 Constrain_Decimal (Def_Id, S);
20596 when Enumeration_Kind =>
20597 Constrain_Enumeration (Def_Id, S);
20598 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
20600 when Ordinary_Fixed_Point_Kind =>
20601 Constrain_Ordinary_Fixed (Def_Id, S);
20604 Constrain_Float (Def_Id, S);
20606 when Integer_Kind =>
20607 Constrain_Integer (Def_Id, S);
20608 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
20610 when E_Record_Type |
20613 E_Incomplete_Type =>
20614 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
20616 if Ekind (Def_Id) = E_Incomplete_Type then
20617 Set_Private_Dependents (Def_Id, New_Elmt_List);
20620 when Private_Kind =>
20621 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
20622 Set_Private_Dependents (Def_Id, New_Elmt_List);
20624 -- In case of an invalid constraint prevent further processing
20625 -- since the type constructed is missing expected fields.
20627 if Etype (Def_Id) = Any_Type then
20631 -- If the full view is that of a task with discriminants,
20632 -- we must constrain both the concurrent type and its
20633 -- corresponding record type. Otherwise we will just propagate
20634 -- the constraint to the full view, if available.
20636 if Present (Full_View (Subtype_Mark_Id))
20637 and then Has_Discriminants (Subtype_Mark_Id)
20638 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
20641 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
20643 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
20644 Constrain_Concurrent (Full_View_Id, S,
20645 Related_Nod, Related_Id, Suffix);
20646 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
20647 Set_Full_View (Def_Id, Full_View_Id);
20649 -- Introduce an explicit reference to the private subtype,
20650 -- to prevent scope anomalies in gigi if first use appears
20651 -- in a nested context, e.g. a later function body.
20652 -- Should this be generated in other contexts than a full
20653 -- type declaration?
20655 if Is_Itype (Def_Id)
20657 Nkind (Parent (P)) = N_Full_Type_Declaration
20659 Build_Itype_Reference (Def_Id, Parent (P));
20663 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
20666 when Concurrent_Kind =>
20667 Constrain_Concurrent (Def_Id, S,
20668 Related_Nod, Related_Id, Suffix);
20671 Error_Msg_N ("invalid subtype mark in subtype indication", S);
20674 -- Size and Convention are always inherited from the base type
20676 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
20677 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
20681 end Process_Subtype;
20683 --------------------------------------------
20684 -- Propagate_Default_Init_Cond_Attributes --
20685 --------------------------------------------
20687 procedure Propagate_Default_Init_Cond_Attributes
20688 (From_Typ : Entity_Id;
20689 To_Typ : Entity_Id;
20690 Parent_To_Derivation : Boolean := False;
20691 Private_To_Full_View : Boolean := False)
20693 procedure Remove_Default_Init_Cond_Procedure (Typ : Entity_Id);
20694 -- Remove the default initial procedure (if any) from the rep chain of
20697 ----------------------------------------
20698 -- Remove_Default_Init_Cond_Procedure --
20699 ----------------------------------------
20701 procedure Remove_Default_Init_Cond_Procedure (Typ : Entity_Id) is
20702 Found : Boolean := False;
20708 Subp := Subprograms_For_Type (Typ);
20709 while Present (Subp) loop
20710 if Is_Default_Init_Cond_Procedure (Subp) then
20716 Subp := Subprograms_For_Type (Subp);
20720 Set_Subprograms_For_Type (Prev, Subprograms_For_Type (Subp));
20721 Set_Subprograms_For_Type (Subp, Empty);
20723 end Remove_Default_Init_Cond_Procedure;
20727 Inherit_Procedure : Boolean := False;
20729 -- Start of processing for Propagate_Default_Init_Cond_Attributes
20732 if Has_Default_Init_Cond (From_Typ) then
20734 -- A derived type inherits the attributes from its parent type
20736 if Parent_To_Derivation then
20737 Set_Has_Inherited_Default_Init_Cond (To_Typ);
20739 -- A full view shares the attributes with its private view
20742 Set_Has_Default_Init_Cond (To_Typ);
20745 Inherit_Procedure := True;
20747 -- Due to the order of expansion, a derived private type is processed
20748 -- by two routines which both attempt to set the attributes related
20749 -- to pragma Default_Initial_Condition - Build_Derived_Type and then
20750 -- Process_Full_View.
20753 -- type Parent_Typ is private
20754 -- with Default_Initial_Condition ...;
20756 -- type Parent_Typ is ...;
20759 -- with Pack; use Pack;
20760 -- package Pack_2 is
20761 -- type Deriv_Typ is private
20762 -- with Default_Initial_Condition ...;
20764 -- type Deriv_Typ is new Parent_Typ;
20767 -- When Build_Derived_Type operates, it sets the attributes on the
20768 -- full view without taking into account that the private view may
20769 -- define its own default initial condition procedure. This becomes
20770 -- apparent in Process_Full_View which must undo some of the work by
20771 -- Build_Derived_Type and propagate the attributes from the private
20772 -- to the full view.
20774 if Private_To_Full_View then
20775 Set_Has_Inherited_Default_Init_Cond (To_Typ, False);
20776 Remove_Default_Init_Cond_Procedure (To_Typ);
20779 -- A type must inherit the default initial condition procedure from a
20780 -- parent type when the parent itself is inheriting the procedure or
20781 -- when it is defining one. This circuitry is also used when dealing
20782 -- with the private / full view of a type.
20784 elsif Has_Inherited_Default_Init_Cond (From_Typ)
20785 or (Parent_To_Derivation
20786 and Present (Get_Pragma
20787 (From_Typ, Pragma_Default_Initial_Condition)))
20789 Set_Has_Inherited_Default_Init_Cond (To_Typ);
20790 Inherit_Procedure := True;
20793 if Inherit_Procedure
20794 and then No (Default_Init_Cond_Procedure (To_Typ))
20796 Set_Default_Init_Cond_Procedure
20797 (To_Typ, Default_Init_Cond_Procedure (From_Typ));
20799 end Propagate_Default_Init_Cond_Attributes;
20801 -----------------------------
20802 -- Record_Type_Declaration --
20803 -----------------------------
20805 procedure Record_Type_Declaration
20810 Def : constant Node_Id := Type_Definition (N);
20811 Is_Tagged : Boolean;
20812 Tag_Comp : Entity_Id;
20815 -- These flags must be initialized before calling Process_Discriminants
20816 -- because this routine makes use of them.
20818 Set_Ekind (T, E_Record_Type);
20820 Init_Size_Align (T);
20821 Set_Interfaces (T, No_Elist);
20822 Set_Stored_Constraint (T, No_Elist);
20823 Set_Default_SSO (T);
20827 if Ada_Version < Ada_2005 or else not Interface_Present (Def) then
20828 if Limited_Present (Def) then
20829 Check_SPARK_05_Restriction ("limited is not allowed", N);
20832 if Abstract_Present (Def) then
20833 Check_SPARK_05_Restriction ("abstract is not allowed", N);
20836 -- The flag Is_Tagged_Type might have already been set by
20837 -- Find_Type_Name if it detected an error for declaration T. This
20838 -- arises in the case of private tagged types where the full view
20839 -- omits the word tagged.
20842 Tagged_Present (Def)
20843 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
20845 Set_Is_Limited_Record (T, Limited_Present (Def));
20848 Set_Is_Tagged_Type (T, True);
20849 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
20852 -- Type is abstract if full declaration carries keyword, or if
20853 -- previous partial view did.
20855 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
20856 or else Abstract_Present (Def));
20859 Check_SPARK_05_Restriction ("interface is not allowed", N);
20862 Analyze_Interface_Declaration (T, Def);
20864 if Present (Discriminant_Specifications (N)) then
20866 ("interface types cannot have discriminants",
20867 Defining_Identifier
20868 (First (Discriminant_Specifications (N))));
20872 -- First pass: if there are self-referential access components,
20873 -- create the required anonymous access type declarations, and if
20874 -- need be an incomplete type declaration for T itself.
20876 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
20878 if Ada_Version >= Ada_2005
20879 and then Present (Interface_List (Def))
20881 Check_Interfaces (N, Def);
20884 Ifaces_List : Elist_Id;
20887 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
20888 -- already in the parents.
20892 Ifaces_List => Ifaces_List,
20893 Exclude_Parents => True);
20895 Set_Interfaces (T, Ifaces_List);
20899 -- Records constitute a scope for the component declarations within.
20900 -- The scope is created prior to the processing of these declarations.
20901 -- Discriminants are processed first, so that they are visible when
20902 -- processing the other components. The Ekind of the record type itself
20903 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
20905 -- Enter record scope
20909 -- If an incomplete or private type declaration was already given for
20910 -- the type, then this scope already exists, and the discriminants have
20911 -- been declared within. We must verify that the full declaration
20912 -- matches the incomplete one.
20914 Check_Or_Process_Discriminants (N, T, Prev);
20916 Set_Is_Constrained (T, not Has_Discriminants (T));
20917 Set_Has_Delayed_Freeze (T, True);
20919 -- For tagged types add a manually analyzed component corresponding
20920 -- to the component _tag, the corresponding piece of tree will be
20921 -- expanded as part of the freezing actions if it is not a CPP_Class.
20925 -- Do not add the tag unless we are in expansion mode
20927 if Expander_Active then
20928 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
20929 Enter_Name (Tag_Comp);
20931 Set_Ekind (Tag_Comp, E_Component);
20932 Set_Is_Tag (Tag_Comp);
20933 Set_Is_Aliased (Tag_Comp);
20934 Set_Etype (Tag_Comp, RTE (RE_Tag));
20935 Set_DT_Entry_Count (Tag_Comp, No_Uint);
20936 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
20937 Init_Component_Location (Tag_Comp);
20939 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
20940 -- implemented interfaces.
20942 if Has_Interfaces (T) then
20943 Add_Interface_Tag_Components (N, T);
20947 Make_Class_Wide_Type (T);
20948 Set_Direct_Primitive_Operations (T, New_Elmt_List);
20951 -- We must suppress range checks when processing record components in
20952 -- the presence of discriminants, since we don't want spurious checks to
20953 -- be generated during their analysis, but Suppress_Range_Checks flags
20954 -- must be reset the after processing the record definition.
20956 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
20957 -- couldn't we just use the normal range check suppression method here.
20958 -- That would seem cleaner ???
20960 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
20961 Set_Kill_Range_Checks (T, True);
20962 Record_Type_Definition (Def, Prev);
20963 Set_Kill_Range_Checks (T, False);
20965 Record_Type_Definition (Def, Prev);
20968 -- Exit from record scope
20972 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
20973 -- the implemented interfaces and associate them an aliased entity.
20976 and then not Is_Empty_List (Interface_List (Def))
20978 Derive_Progenitor_Subprograms (T, T);
20981 Check_Function_Writable_Actuals (N);
20982 end Record_Type_Declaration;
20984 ----------------------------
20985 -- Record_Type_Definition --
20986 ----------------------------
20988 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
20989 Component : Entity_Id;
20990 Ctrl_Components : Boolean := False;
20991 Final_Storage_Only : Boolean;
20995 if Ekind (Prev_T) = E_Incomplete_Type then
20996 T := Full_View (Prev_T);
21001 -- In SPARK, tagged types and type extensions may only be declared in
21002 -- the specification of library unit packages.
21004 if Present (Def) and then Is_Tagged_Type (T) then
21010 if Nkind (Parent (Def)) = N_Full_Type_Declaration then
21011 Typ := Parent (Def);
21014 (Nkind (Parent (Def)) = N_Derived_Type_Definition);
21015 Typ := Parent (Parent (Def));
21018 Ctxt := Parent (Typ);
21020 if Nkind (Ctxt) = N_Package_Body
21021 and then Nkind (Parent (Ctxt)) = N_Compilation_Unit
21023 Check_SPARK_05_Restriction
21024 ("type should be defined in package specification", Typ);
21026 elsif Nkind (Ctxt) /= N_Package_Specification
21027 or else Nkind (Parent (Parent (Ctxt))) /= N_Compilation_Unit
21029 Check_SPARK_05_Restriction
21030 ("type should be defined in library unit package", Typ);
21035 Final_Storage_Only := not Is_Controlled (T);
21037 -- Ada 2005: Check whether an explicit Limited is present in a derived
21038 -- type declaration.
21040 if Nkind (Parent (Def)) = N_Derived_Type_Definition
21041 and then Limited_Present (Parent (Def))
21043 Set_Is_Limited_Record (T);
21046 -- If the component list of a record type is defined by the reserved
21047 -- word null and there is no discriminant part, then the record type has
21048 -- no components and all records of the type are null records (RM 3.7)
21049 -- This procedure is also called to process the extension part of a
21050 -- record extension, in which case the current scope may have inherited
21054 or else No (Component_List (Def))
21055 or else Null_Present (Component_List (Def))
21057 if not Is_Tagged_Type (T) then
21058 Check_SPARK_05_Restriction ("untagged record cannot be null", Def);
21062 Analyze_Declarations (Component_Items (Component_List (Def)));
21064 if Present (Variant_Part (Component_List (Def))) then
21065 Check_SPARK_05_Restriction ("variant part is not allowed", Def);
21066 Analyze (Variant_Part (Component_List (Def)));
21070 -- After completing the semantic analysis of the record definition,
21071 -- record components, both new and inherited, are accessible. Set their
21072 -- kind accordingly. Exclude malformed itypes from illegal declarations,
21073 -- whose Ekind may be void.
21075 Component := First_Entity (Current_Scope);
21076 while Present (Component) loop
21077 if Ekind (Component) = E_Void
21078 and then not Is_Itype (Component)
21080 Set_Ekind (Component, E_Component);
21081 Init_Component_Location (Component);
21084 if Has_Task (Etype (Component)) then
21088 if Has_Protected (Etype (Component)) then
21089 Set_Has_Protected (T);
21092 if Ekind (Component) /= E_Component then
21095 -- Do not set Has_Controlled_Component on a class-wide equivalent
21096 -- type. See Make_CW_Equivalent_Type.
21098 elsif not Is_Class_Wide_Equivalent_Type (T)
21099 and then (Has_Controlled_Component (Etype (Component))
21100 or else (Chars (Component) /= Name_uParent
21101 and then Is_Controlled (Etype (Component))))
21103 Set_Has_Controlled_Component (T, True);
21104 Final_Storage_Only :=
21106 and then Finalize_Storage_Only (Etype (Component));
21107 Ctrl_Components := True;
21110 Next_Entity (Component);
21113 -- A Type is Finalize_Storage_Only only if all its controlled components
21116 if Ctrl_Components then
21117 Set_Finalize_Storage_Only (T, Final_Storage_Only);
21120 -- Place reference to end record on the proper entity, which may
21121 -- be a partial view.
21123 if Present (Def) then
21124 Process_End_Label (Def, 'e', Prev_T);
21126 end Record_Type_Definition;
21128 ------------------------
21129 -- Replace_Components --
21130 ------------------------
21132 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
21133 function Process (N : Node_Id) return Traverse_Result;
21139 function Process (N : Node_Id) return Traverse_Result is
21143 if Nkind (N) = N_Discriminant_Specification then
21144 Comp := First_Discriminant (Typ);
21145 while Present (Comp) loop
21146 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21147 Set_Defining_Identifier (N, Comp);
21151 Next_Discriminant (Comp);
21154 elsif Nkind (N) = N_Component_Declaration then
21155 Comp := First_Component (Typ);
21156 while Present (Comp) loop
21157 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21158 Set_Defining_Identifier (N, Comp);
21162 Next_Component (Comp);
21169 procedure Replace is new Traverse_Proc (Process);
21171 -- Start of processing for Replace_Components
21175 end Replace_Components;
21177 -------------------------------
21178 -- Set_Completion_Referenced --
21179 -------------------------------
21181 procedure Set_Completion_Referenced (E : Entity_Id) is
21183 -- If in main unit, mark entity that is a completion as referenced,
21184 -- warnings go on the partial view when needed.
21186 if In_Extended_Main_Source_Unit (E) then
21187 Set_Referenced (E);
21189 end Set_Completion_Referenced;
21191 ---------------------
21192 -- Set_Default_SSO --
21193 ---------------------
21195 procedure Set_Default_SSO (T : Entity_Id) is
21197 case Opt.Default_SSO is
21201 Set_SSO_Set_Low_By_Default (T, True);
21203 Set_SSO_Set_High_By_Default (T, True);
21205 raise Program_Error;
21207 end Set_Default_SSO;
21209 ---------------------
21210 -- Set_Fixed_Range --
21211 ---------------------
21213 -- The range for fixed-point types is complicated by the fact that we
21214 -- do not know the exact end points at the time of the declaration. This
21215 -- is true for three reasons:
21217 -- A size clause may affect the fudging of the end-points.
21218 -- A small clause may affect the values of the end-points.
21219 -- We try to include the end-points if it does not affect the size.
21221 -- This means that the actual end-points must be established at the
21222 -- point when the type is frozen. Meanwhile, we first narrow the range
21223 -- as permitted (so that it will fit if necessary in a small specified
21224 -- size), and then build a range subtree with these narrowed bounds.
21225 -- Set_Fixed_Range constructs the range from real literal values, and
21226 -- sets the range as the Scalar_Range of the given fixed-point type entity.
21228 -- The parent of this range is set to point to the entity so that it is
21229 -- properly hooked into the tree (unlike normal Scalar_Range entries for
21230 -- other scalar types, which are just pointers to the range in the
21231 -- original tree, this would otherwise be an orphan).
21233 -- The tree is left unanalyzed. When the type is frozen, the processing
21234 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
21235 -- analyzed, and uses this as an indication that it should complete
21236 -- work on the range (it will know the final small and size values).
21238 procedure Set_Fixed_Range
21244 S : constant Node_Id :=
21246 Low_Bound => Make_Real_Literal (Loc, Lo),
21247 High_Bound => Make_Real_Literal (Loc, Hi));
21249 Set_Scalar_Range (E, S);
21252 -- Before the freeze point, the bounds of a fixed point are universal
21253 -- and carry the corresponding type.
21255 Set_Etype (Low_Bound (S), Universal_Real);
21256 Set_Etype (High_Bound (S), Universal_Real);
21257 end Set_Fixed_Range;
21259 ----------------------------------
21260 -- Set_Scalar_Range_For_Subtype --
21261 ----------------------------------
21263 procedure Set_Scalar_Range_For_Subtype
21264 (Def_Id : Entity_Id;
21268 Kind : constant Entity_Kind := Ekind (Def_Id);
21271 -- Defend against previous error
21273 if Nkind (R) = N_Error then
21277 Set_Scalar_Range (Def_Id, R);
21279 -- We need to link the range into the tree before resolving it so
21280 -- that types that are referenced, including importantly the subtype
21281 -- itself, are properly frozen (Freeze_Expression requires that the
21282 -- expression be properly linked into the tree). Of course if it is
21283 -- already linked in, then we do not disturb the current link.
21285 if No (Parent (R)) then
21286 Set_Parent (R, Def_Id);
21289 -- Reset the kind of the subtype during analysis of the range, to
21290 -- catch possible premature use in the bounds themselves.
21292 Set_Ekind (Def_Id, E_Void);
21293 Process_Range_Expr_In_Decl (R, Subt, Subtyp => Def_Id);
21294 Set_Ekind (Def_Id, Kind);
21295 end Set_Scalar_Range_For_Subtype;
21297 --------------------------------------------------------
21298 -- Set_Stored_Constraint_From_Discriminant_Constraint --
21299 --------------------------------------------------------
21301 procedure Set_Stored_Constraint_From_Discriminant_Constraint
21305 -- Make sure set if encountered during Expand_To_Stored_Constraint
21307 Set_Stored_Constraint (E, No_Elist);
21309 -- Give it the right value
21311 if Is_Constrained (E) and then Has_Discriminants (E) then
21312 Set_Stored_Constraint (E,
21313 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
21315 end Set_Stored_Constraint_From_Discriminant_Constraint;
21317 -------------------------------------
21318 -- Signed_Integer_Type_Declaration --
21319 -------------------------------------
21321 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
21322 Implicit_Base : Entity_Id;
21323 Base_Typ : Entity_Id;
21326 Errs : Boolean := False;
21330 function Can_Derive_From (E : Entity_Id) return Boolean;
21331 -- Determine whether given bounds allow derivation from specified type
21333 procedure Check_Bound (Expr : Node_Id);
21334 -- Check bound to make sure it is integral and static. If not, post
21335 -- appropriate error message and set Errs flag
21337 ---------------------
21338 -- Can_Derive_From --
21339 ---------------------
21341 -- Note we check both bounds against both end values, to deal with
21342 -- strange types like ones with a range of 0 .. -12341234.
21344 function Can_Derive_From (E : Entity_Id) return Boolean is
21345 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
21346 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
21348 return Lo <= Lo_Val and then Lo_Val <= Hi
21350 Lo <= Hi_Val and then Hi_Val <= Hi;
21351 end Can_Derive_From;
21357 procedure Check_Bound (Expr : Node_Id) is
21359 -- If a range constraint is used as an integer type definition, each
21360 -- bound of the range must be defined by a static expression of some
21361 -- integer type, but the two bounds need not have the same integer
21362 -- type (Negative bounds are allowed.) (RM 3.5.4)
21364 if not Is_Integer_Type (Etype (Expr)) then
21366 ("integer type definition bounds must be of integer type", Expr);
21369 elsif not Is_OK_Static_Expression (Expr) then
21370 Flag_Non_Static_Expr
21371 ("non-static expression used for integer type bound!", Expr);
21374 -- The bounds are folded into literals, and we set their type to be
21375 -- universal, to avoid typing difficulties: we cannot set the type
21376 -- of the literal to the new type, because this would be a forward
21377 -- reference for the back end, and if the original type is user-
21378 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
21381 if Is_Entity_Name (Expr) then
21382 Fold_Uint (Expr, Expr_Value (Expr), True);
21385 Set_Etype (Expr, Universal_Integer);
21389 -- Start of processing for Signed_Integer_Type_Declaration
21392 -- Create an anonymous base type
21395 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
21397 -- Analyze and check the bounds, they can be of any integer type
21399 Lo := Low_Bound (Def);
21400 Hi := High_Bound (Def);
21402 -- Arbitrarily use Integer as the type if either bound had an error
21404 if Hi = Error or else Lo = Error then
21405 Base_Typ := Any_Integer;
21406 Set_Error_Posted (T, True);
21408 -- Here both bounds are OK expressions
21411 Analyze_And_Resolve (Lo, Any_Integer);
21412 Analyze_And_Resolve (Hi, Any_Integer);
21418 Hi := Type_High_Bound (Standard_Long_Long_Integer);
21419 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
21422 -- Find type to derive from
21424 Lo_Val := Expr_Value (Lo);
21425 Hi_Val := Expr_Value (Hi);
21427 if Can_Derive_From (Standard_Short_Short_Integer) then
21428 Base_Typ := Base_Type (Standard_Short_Short_Integer);
21430 elsif Can_Derive_From (Standard_Short_Integer) then
21431 Base_Typ := Base_Type (Standard_Short_Integer);
21433 elsif Can_Derive_From (Standard_Integer) then
21434 Base_Typ := Base_Type (Standard_Integer);
21436 elsif Can_Derive_From (Standard_Long_Integer) then
21437 Base_Typ := Base_Type (Standard_Long_Integer);
21439 elsif Can_Derive_From (Standard_Long_Long_Integer) then
21440 Check_Restriction (No_Long_Long_Integers, Def);
21441 Base_Typ := Base_Type (Standard_Long_Long_Integer);
21444 Base_Typ := Base_Type (Standard_Long_Long_Integer);
21445 Error_Msg_N ("integer type definition bounds out of range", Def);
21446 Hi := Type_High_Bound (Standard_Long_Long_Integer);
21447 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
21451 -- Complete both implicit base and declared first subtype entities. The
21452 -- inheritance of the rep item chain ensures that SPARK-related pragmas
21453 -- are not clobbered when the signed integer type acts as a full view of
21456 Set_Etype (Implicit_Base, Base_Typ);
21457 Set_Size_Info (Implicit_Base, Base_Typ);
21458 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
21459 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
21460 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
21462 Set_Ekind (T, E_Signed_Integer_Subtype);
21463 Set_Etype (T, Implicit_Base);
21464 Set_Size_Info (T, Implicit_Base);
21465 Inherit_Rep_Item_Chain (T, Implicit_Base);
21466 Set_Scalar_Range (T, Def);
21467 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
21468 Set_Is_Constrained (T);
21469 end Signed_Integer_Type_Declaration;