1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2015, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Aspects; use Aspects;
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Contracts; use Contracts;
30 with Debug; use Debug;
31 with Elists; use Elists;
32 with Einfo; use Einfo;
33 with Errout; use Errout;
34 with Eval_Fat; use Eval_Fat;
35 with Exp_Ch3; use Exp_Ch3;
36 with Exp_Ch9; use Exp_Ch9;
37 with Exp_Disp; use Exp_Disp;
38 with Exp_Dist; use Exp_Dist;
39 with Exp_Tss; use Exp_Tss;
40 with Exp_Util; use Exp_Util;
41 with Fname; use Fname;
42 with Freeze; use Freeze;
43 with Ghost; use Ghost;
44 with Itypes; use Itypes;
45 with Layout; use Layout;
47 with Lib.Xref; use Lib.Xref;
48 with Namet; use Namet;
49 with Nmake; use Nmake;
51 with Restrict; use Restrict;
52 with Rident; use Rident;
53 with Rtsfind; use Rtsfind;
55 with Sem_Aux; use Sem_Aux;
56 with Sem_Case; use Sem_Case;
57 with Sem_Cat; use Sem_Cat;
58 with Sem_Ch6; use Sem_Ch6;
59 with Sem_Ch7; use Sem_Ch7;
60 with Sem_Ch8; use Sem_Ch8;
61 with Sem_Ch13; use Sem_Ch13;
62 with Sem_Dim; use Sem_Dim;
63 with Sem_Disp; use Sem_Disp;
64 with Sem_Dist; use Sem_Dist;
65 with Sem_Elim; use Sem_Elim;
66 with Sem_Eval; use Sem_Eval;
67 with Sem_Mech; use Sem_Mech;
68 with Sem_Res; use Sem_Res;
69 with Sem_Smem; use Sem_Smem;
70 with Sem_Type; use Sem_Type;
71 with Sem_Util; use Sem_Util;
72 with Sem_Warn; use Sem_Warn;
73 with Stand; use Stand;
74 with Sinfo; use Sinfo;
75 with Sinput; use Sinput;
76 with Snames; use Snames;
77 with Targparm; use Targparm;
78 with Tbuild; use Tbuild;
79 with Ttypes; use Ttypes;
80 with Uintp; use Uintp;
81 with Urealp; use Urealp;
83 package body Sem_Ch3 is
85 -----------------------
86 -- Local Subprograms --
87 -----------------------
89 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id);
90 -- Ada 2005 (AI-251): Add the tag components corresponding to all the
91 -- abstract interface types implemented by a record type or a derived
94 procedure Build_Derived_Type
96 Parent_Type : Entity_Id;
97 Derived_Type : Entity_Id;
98 Is_Completion : Boolean;
99 Derive_Subps : Boolean := True);
100 -- Create and decorate a Derived_Type given the Parent_Type entity. N is
101 -- the N_Full_Type_Declaration node containing the derived type definition.
102 -- Parent_Type is the entity for the parent type in the derived type
103 -- definition and Derived_Type the actual derived type. Is_Completion must
104 -- be set to False if Derived_Type is the N_Defining_Identifier node in N
105 -- (i.e. Derived_Type = Defining_Identifier (N)). In this case N is not the
106 -- completion of a private type declaration. If Is_Completion is set to
107 -- True, N is the completion of a private type declaration and Derived_Type
108 -- is different from the defining identifier inside N (i.e. Derived_Type /=
109 -- Defining_Identifier (N)). Derive_Subps indicates whether the parent
110 -- subprograms should be derived. The only case where this parameter is
111 -- False is when Build_Derived_Type is recursively called to process an
112 -- implicit derived full type for a type derived from a private type (in
113 -- that case the subprograms must only be derived for the private view of
116 -- ??? These flags need a bit of re-examination and re-documentation:
117 -- ??? are they both necessary (both seem related to the recursion)?
119 procedure Build_Derived_Access_Type
121 Parent_Type : Entity_Id;
122 Derived_Type : Entity_Id);
123 -- Subsidiary procedure to Build_Derived_Type. For a derived access type,
124 -- create an implicit base if the parent type is constrained or if the
125 -- subtype indication has a constraint.
127 procedure Build_Derived_Array_Type
129 Parent_Type : Entity_Id;
130 Derived_Type : Entity_Id);
131 -- Subsidiary procedure to Build_Derived_Type. For a derived array type,
132 -- create an implicit base if the parent type is constrained or if the
133 -- subtype indication has a constraint.
135 procedure Build_Derived_Concurrent_Type
137 Parent_Type : Entity_Id;
138 Derived_Type : Entity_Id);
139 -- Subsidiary procedure to Build_Derived_Type. For a derived task or
140 -- protected type, inherit entries and protected subprograms, check
141 -- legality of discriminant constraints if any.
143 procedure Build_Derived_Enumeration_Type
145 Parent_Type : Entity_Id;
146 Derived_Type : Entity_Id);
147 -- Subsidiary procedure to Build_Derived_Type. For a derived enumeration
148 -- type, we must create a new list of literals. Types derived from
149 -- Character and [Wide_]Wide_Character are special-cased.
151 procedure Build_Derived_Numeric_Type
153 Parent_Type : Entity_Id;
154 Derived_Type : Entity_Id);
155 -- Subsidiary procedure to Build_Derived_Type. For numeric types, create
156 -- an anonymous base type, and propagate constraint to subtype if needed.
158 procedure Build_Derived_Private_Type
160 Parent_Type : Entity_Id;
161 Derived_Type : Entity_Id;
162 Is_Completion : Boolean;
163 Derive_Subps : Boolean := True);
164 -- Subsidiary procedure to Build_Derived_Type. This procedure is complex
165 -- because the parent may or may not have a completion, and the derivation
166 -- may itself be a completion.
168 procedure Build_Derived_Record_Type
170 Parent_Type : Entity_Id;
171 Derived_Type : Entity_Id;
172 Derive_Subps : Boolean := True);
173 -- Subsidiary procedure used for tagged and untagged record types
174 -- by Build_Derived_Type and Analyze_Private_Extension_Declaration.
175 -- All parameters are as in Build_Derived_Type except that N, in
176 -- addition to being an N_Full_Type_Declaration node, can also be an
177 -- N_Private_Extension_Declaration node. See the definition of this routine
178 -- for much more info. Derive_Subps indicates whether subprograms should be
179 -- derived from the parent type. The only case where Derive_Subps is False
180 -- is for an implicit derived full type for a type derived from a private
181 -- type (see Build_Derived_Type).
183 procedure Build_Discriminal (Discrim : Entity_Id);
184 -- Create the discriminal corresponding to discriminant Discrim, that is
185 -- the parameter corresponding to Discrim to be used in initialization
186 -- procedures for the type where Discrim is a discriminant. Discriminals
187 -- are not used during semantic analysis, and are not fully defined
188 -- entities until expansion. Thus they are not given a scope until
189 -- initialization procedures are built.
191 function Build_Discriminant_Constraints
194 Derived_Def : Boolean := False) return Elist_Id;
195 -- Validate discriminant constraints and return the list of the constraints
196 -- in order of discriminant declarations, where T is the discriminated
197 -- unconstrained type. Def is the N_Subtype_Indication node where the
198 -- discriminants constraints for T are specified. Derived_Def is True
199 -- when building the discriminant constraints in a derived type definition
200 -- of the form "type D (...) is new T (xxx)". In this case T is the parent
201 -- type and Def is the constraint "(xxx)" on T and this routine sets the
202 -- Corresponding_Discriminant field of the discriminants in the derived
203 -- type D to point to the corresponding discriminants in the parent type T.
205 procedure Build_Discriminated_Subtype
209 Related_Nod : Node_Id;
210 For_Access : Boolean := False);
211 -- Subsidiary procedure to Constrain_Discriminated_Type and to
212 -- Process_Incomplete_Dependents. Given
214 -- T (a possibly discriminated base type)
215 -- Def_Id (a very partially built subtype for T),
217 -- the call completes Def_Id to be the appropriate E_*_Subtype.
219 -- The Elist is the list of discriminant constraints if any (it is set
220 -- to No_Elist if T is not a discriminated type, and to an empty list if
221 -- T has discriminants but there are no discriminant constraints). The
222 -- Related_Nod is the same as Decl_Node in Create_Constrained_Components.
223 -- The For_Access says whether or not this subtype is really constraining
224 -- an access type. That is its sole purpose is the designated type of an
225 -- access type -- in which case a Private_Subtype Is_For_Access_Subtype
226 -- is built to avoid freezing T when the access subtype is frozen.
228 function Build_Scalar_Bound
231 Der_T : Entity_Id) return Node_Id;
232 -- The bounds of a derived scalar type are conversions of the bounds of
233 -- the parent type. Optimize the representation if the bounds are literals.
234 -- Needs a more complete spec--what are the parameters exactly, and what
235 -- exactly is the returned value, and how is Bound affected???
237 procedure Build_Underlying_Full_View
241 -- If the completion of a private type is itself derived from a private
242 -- type, or if the full view of a private subtype is itself private, the
243 -- back-end has no way to compute the actual size of this type. We build
244 -- an internal subtype declaration of the proper parent type to convey
245 -- this information. This extra mechanism is needed because a full
246 -- view cannot itself have a full view (it would get clobbered during
249 procedure Check_Access_Discriminant_Requires_Limited
252 -- Check the restriction that the type to which an access discriminant
253 -- belongs must be a concurrent type or a descendant of a type with
254 -- the reserved word 'limited' in its declaration.
256 procedure Check_Anonymous_Access_Components
260 Comp_List : Node_Id);
261 -- Ada 2005 AI-382: an access component in a record definition can refer to
262 -- the enclosing record, in which case it denotes the type itself, and not
263 -- the current instance of the type. We create an anonymous access type for
264 -- the component, and flag it as an access to a component, so accessibility
265 -- checks are properly performed on it. The declaration of the access type
266 -- is placed ahead of that of the record to prevent order-of-elaboration
267 -- circularity issues in Gigi. We create an incomplete type for the record
268 -- declaration, which is the designated type of the anonymous access.
270 procedure Check_Delta_Expression (E : Node_Id);
271 -- Check that the expression represented by E is suitable for use as a
272 -- delta expression, i.e. it is of real type and is static.
274 procedure Check_Digits_Expression (E : Node_Id);
275 -- Check that the expression represented by E is suitable for use as a
276 -- digits expression, i.e. it is of integer type, positive and static.
278 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id);
279 -- Validate the initialization of an object declaration. T is the required
280 -- type, and Exp is the initialization expression.
282 procedure Check_Interfaces (N : Node_Id; Def : Node_Id);
283 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
285 procedure Check_Or_Process_Discriminants
288 Prev : Entity_Id := Empty);
289 -- If N is the full declaration of the completion T of an incomplete or
290 -- private type, check its discriminants (which are already known to be
291 -- conformant with those of the partial view, see Find_Type_Name),
292 -- otherwise process them. Prev is the entity of the partial declaration,
295 procedure Check_Real_Bound (Bound : Node_Id);
296 -- Check given bound for being of real type and static. If not, post an
297 -- appropriate message, and rewrite the bound with the real literal zero.
299 procedure Constant_Redeclaration
303 -- Various checks on legality of full declaration of deferred constant.
304 -- Id is the entity for the redeclaration, N is the N_Object_Declaration,
305 -- node. The caller has not yet set any attributes of this entity.
307 function Contain_Interface
309 Ifaces : Elist_Id) return Boolean;
310 -- Ada 2005: Determine whether Iface is present in the list Ifaces
312 procedure Convert_Scalar_Bounds
314 Parent_Type : Entity_Id;
315 Derived_Type : Entity_Id;
317 -- For derived scalar types, convert the bounds in the type definition to
318 -- the derived type, and complete their analysis. Given a constraint of the
319 -- form ".. new T range Lo .. Hi", Lo and Hi are analyzed and resolved with
320 -- T'Base, the parent_type. The bounds of the derived type (the anonymous
321 -- base) are copies of Lo and Hi. Finally, the bounds of the derived
322 -- subtype are conversions of those bounds to the derived_type, so that
323 -- their typing is consistent.
325 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id);
326 -- Copies attributes from array base type T2 to array base type T1. Copies
327 -- only attributes that apply to base types, but not subtypes.
329 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id);
330 -- Copies attributes from array subtype T2 to array subtype T1. Copies
331 -- attributes that apply to both subtypes and base types.
333 procedure Create_Constrained_Components
337 Constraints : Elist_Id);
338 -- Build the list of entities for a constrained discriminated record
339 -- subtype. If a component depends on a discriminant, replace its subtype
340 -- using the discriminant values in the discriminant constraint. Subt
341 -- is the defining identifier for the subtype whose list of constrained
342 -- entities we will create. Decl_Node is the type declaration node where
343 -- we will attach all the itypes created. Typ is the base discriminated
344 -- type for the subtype Subt. Constraints is the list of discriminant
345 -- constraints for Typ.
347 function Constrain_Component_Type
349 Constrained_Typ : Entity_Id;
350 Related_Node : Node_Id;
352 Constraints : Elist_Id) return Entity_Id;
353 -- Given a discriminated base type Typ, a list of discriminant constraints,
354 -- Constraints, for Typ and a component Comp of Typ, create and return the
355 -- type corresponding to Etype (Comp) where all discriminant references
356 -- are replaced with the corresponding constraint. If Etype (Comp) contains
357 -- no discriminant references then it is returned as-is. Constrained_Typ
358 -- is the final constrained subtype to which the constrained component
359 -- belongs. Related_Node is the node where we attach all created itypes.
361 procedure Constrain_Access
362 (Def_Id : in out Entity_Id;
364 Related_Nod : Node_Id);
365 -- Apply a list of constraints to an access type. If Def_Id is empty, it is
366 -- an anonymous type created for a subtype indication. In that case it is
367 -- created in the procedure and attached to Related_Nod.
369 procedure Constrain_Array
370 (Def_Id : in out Entity_Id;
372 Related_Nod : Node_Id;
373 Related_Id : Entity_Id;
375 -- Apply a list of index constraints to an unconstrained array type. The
376 -- first parameter is the entity for the resulting subtype. A value of
377 -- Empty for Def_Id indicates that an implicit type must be created, but
378 -- creation is delayed (and must be done by this procedure) because other
379 -- subsidiary implicit types must be created first (which is why Def_Id
380 -- is an in/out parameter). The second parameter is a subtype indication
381 -- node for the constrained array to be created (e.g. something of the
382 -- form string (1 .. 10)). Related_Nod gives the place where this type
383 -- has to be inserted in the tree. The Related_Id and Suffix parameters
384 -- are used to build the associated Implicit type name.
386 procedure Constrain_Concurrent
387 (Def_Id : in out Entity_Id;
389 Related_Nod : Node_Id;
390 Related_Id : Entity_Id;
392 -- Apply list of discriminant constraints to an unconstrained concurrent
395 -- SI is the N_Subtype_Indication node containing the constraint and
396 -- the unconstrained type to constrain.
398 -- Def_Id is the entity for the resulting constrained subtype. A value
399 -- of Empty for Def_Id indicates that an implicit type must be created,
400 -- but creation is delayed (and must be done by this procedure) because
401 -- other subsidiary implicit types must be created first (which is why
402 -- Def_Id is an in/out parameter).
404 -- Related_Nod gives the place where this type has to be inserted
407 -- The last two arguments are used to create its external name if needed.
409 function Constrain_Corresponding_Record
410 (Prot_Subt : Entity_Id;
411 Corr_Rec : Entity_Id;
412 Related_Nod : Node_Id) return Entity_Id;
413 -- When constraining a protected type or task type with discriminants,
414 -- constrain the corresponding record with the same discriminant values.
416 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id);
417 -- Constrain a decimal fixed point type with a digits constraint and/or a
418 -- range constraint, and build E_Decimal_Fixed_Point_Subtype entity.
420 procedure Constrain_Discriminated_Type
423 Related_Nod : Node_Id;
424 For_Access : Boolean := False);
425 -- Process discriminant constraints of composite type. Verify that values
426 -- have been provided for all discriminants, that the original type is
427 -- unconstrained, and that the types of the supplied expressions match
428 -- the discriminant types. The first three parameters are like in routine
429 -- Constrain_Concurrent. See Build_Discriminated_Subtype for an explanation
432 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id);
433 -- Constrain an enumeration type with a range constraint. This is identical
434 -- to Constrain_Integer, but for the Ekind of the resulting subtype.
436 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id);
437 -- Constrain a floating point type with either a digits constraint
438 -- and/or a range constraint, building a E_Floating_Point_Subtype.
440 procedure Constrain_Index
443 Related_Nod : Node_Id;
444 Related_Id : Entity_Id;
447 -- Process an index constraint S in a constrained array declaration. The
448 -- constraint can be a subtype name, or a range with or without an explicit
449 -- subtype mark. The index is the corresponding index of the unconstrained
450 -- array. The Related_Id and Suffix parameters are used to build the
451 -- associated Implicit type name.
453 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id);
454 -- Build subtype of a signed or modular integer type
456 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id);
457 -- Constrain an ordinary fixed point type with a range constraint, and
458 -- build an E_Ordinary_Fixed_Point_Subtype entity.
460 procedure Copy_And_Swap (Priv, Full : Entity_Id);
461 -- Copy the Priv entity into the entity of its full declaration then swap
462 -- the two entities in such a manner that the former private type is now
463 -- seen as a full type.
465 procedure Decimal_Fixed_Point_Type_Declaration
468 -- Create a new decimal fixed point type, and apply the constraint to
469 -- obtain a subtype of this new type.
471 procedure Complete_Private_Subtype
474 Full_Base : Entity_Id;
475 Related_Nod : Node_Id);
476 -- Complete the implicit full view of a private subtype by setting the
477 -- appropriate semantic fields. If the full view of the parent is a record
478 -- type, build constrained components of subtype.
480 procedure Derive_Progenitor_Subprograms
481 (Parent_Type : Entity_Id;
482 Tagged_Type : Entity_Id);
483 -- Ada 2005 (AI-251): To complete type derivation, collect the primitive
484 -- operations of progenitors of Tagged_Type, and replace the subsidiary
485 -- subtypes with Tagged_Type, to build the specs of the inherited interface
486 -- primitives. The derived primitives are aliased to those of the
487 -- interface. This routine takes care also of transferring to the full view
488 -- subprograms associated with the partial view of Tagged_Type that cover
489 -- interface primitives.
491 procedure Derived_Standard_Character
493 Parent_Type : Entity_Id;
494 Derived_Type : Entity_Id);
495 -- Subsidiary procedure to Build_Derived_Enumeration_Type which handles
496 -- derivations from types Standard.Character and Standard.Wide_Character.
498 procedure Derived_Type_Declaration
501 Is_Completion : Boolean);
502 -- Process a derived type declaration. Build_Derived_Type is invoked
503 -- to process the actual derived type definition. Parameters N and
504 -- Is_Completion have the same meaning as in Build_Derived_Type.
505 -- T is the N_Defining_Identifier for the entity defined in the
506 -- N_Full_Type_Declaration node N, that is T is the derived type.
508 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id);
509 -- Insert each literal in symbol table, as an overloadable identifier. Each
510 -- enumeration type is mapped into a sequence of integers, and each literal
511 -- is defined as a constant with integer value. If any of the literals are
512 -- character literals, the type is a character type, which means that
513 -- strings are legal aggregates for arrays of components of the type.
515 function Expand_To_Stored_Constraint
517 Constraint : Elist_Id) return Elist_Id;
518 -- Given a constraint (i.e. a list of expressions) on the discriminants of
519 -- Typ, expand it into a constraint on the stored discriminants and return
520 -- the new list of expressions constraining the stored discriminants.
522 function Find_Type_Of_Object
524 Related_Nod : Node_Id) return Entity_Id;
525 -- Get type entity for object referenced by Obj_Def, attaching the implicit
526 -- types generated to Related_Nod.
528 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id);
529 -- Create a new float and apply the constraint to obtain subtype of it
531 function Has_Range_Constraint (N : Node_Id) return Boolean;
532 -- Given an N_Subtype_Indication node N, return True if a range constraint
533 -- is present, either directly, or as part of a digits or delta constraint.
534 -- In addition, a digits constraint in the decimal case returns True, since
535 -- it establishes a default range if no explicit range is present.
537 function Inherit_Components
539 Parent_Base : Entity_Id;
540 Derived_Base : Entity_Id;
542 Inherit_Discr : Boolean;
543 Discs : Elist_Id) return Elist_Id;
544 -- Called from Build_Derived_Record_Type to inherit the components of
545 -- Parent_Base (a base type) into the Derived_Base (the derived base type).
546 -- For more information on derived types and component inheritance please
547 -- consult the comment above the body of Build_Derived_Record_Type.
549 -- N is the original derived type declaration
551 -- Is_Tagged is set if we are dealing with tagged types
553 -- If Inherit_Discr is set, Derived_Base inherits its discriminants from
554 -- Parent_Base, otherwise no discriminants are inherited.
556 -- Discs gives the list of constraints that apply to Parent_Base in the
557 -- derived type declaration. If Discs is set to No_Elist, then we have
558 -- the following situation:
560 -- type Parent (D1..Dn : ..) is [tagged] record ...;
561 -- type Derived is new Parent [with ...];
563 -- which gets treated as
565 -- type Derived (D1..Dn : ..) is new Parent (D1,..,Dn) [with ...];
567 -- For untagged types the returned value is an association list. The list
568 -- starts from the association (Parent_Base => Derived_Base), and then it
569 -- contains a sequence of the associations of the form
571 -- (Old_Component => New_Component),
573 -- where Old_Component is the Entity_Id of a component in Parent_Base and
574 -- New_Component is the Entity_Id of the corresponding component in
575 -- Derived_Base. For untagged records, this association list is needed when
576 -- copying the record declaration for the derived base. In the tagged case
577 -- the value returned is irrelevant.
579 procedure Inherit_Predicate_Flags (Subt, Par : Entity_Id);
580 -- Propagate static and dynamic predicate flags from a parent to the
581 -- subtype in a subtype declaration with and without constraints.
583 function Is_EVF_Procedure (Subp : Entity_Id) return Boolean;
584 -- Subsidiary to Check_Abstract_Overriding and Derive_Subprogram.
585 -- Determine whether subprogram Subp is a procedure subject to pragma
586 -- Extensions_Visible with value False and has at least one controlling
587 -- parameter of mode OUT.
589 function Is_Valid_Constraint_Kind
591 Constraint_Kind : Node_Kind) return Boolean;
592 -- Returns True if it is legal to apply the given kind of constraint to the
593 -- given kind of type (index constraint to an array type, for example).
595 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id);
596 -- Create new modular type. Verify that modulus is in bounds
598 procedure New_Concatenation_Op (Typ : Entity_Id);
599 -- Create an abbreviated declaration for an operator in order to
600 -- materialize concatenation on array types.
602 procedure Ordinary_Fixed_Point_Type_Declaration
605 -- Create a new ordinary fixed point type, and apply the constraint to
606 -- obtain subtype of it.
608 procedure Prepare_Private_Subtype_Completion
610 Related_Nod : Node_Id);
611 -- Id is a subtype of some private type. Creates the full declaration
612 -- associated with Id whenever possible, i.e. when the full declaration
613 -- of the base type is already known. Records each subtype into
614 -- Private_Dependents of the base type.
616 procedure Process_Incomplete_Dependents
620 -- Process all entities that depend on an incomplete type. There include
621 -- subtypes, subprogram types that mention the incomplete type in their
622 -- profiles, and subprogram with access parameters that designate the
625 -- Inc_T is the defining identifier of an incomplete type declaration, its
626 -- Ekind is E_Incomplete_Type.
628 -- N is the corresponding N_Full_Type_Declaration for Inc_T.
630 -- Full_T is N's defining identifier.
632 -- Subtypes of incomplete types with discriminants are completed when the
633 -- parent type is. This is simpler than private subtypes, because they can
634 -- only appear in the same scope, and there is no need to exchange views.
635 -- Similarly, access_to_subprogram types may have a parameter or a return
636 -- type that is an incomplete type, and that must be replaced with the
639 -- If the full type is tagged, subprogram with access parameters that
640 -- designated the incomplete may be primitive operations of the full type,
641 -- and have to be processed accordingly.
643 procedure Process_Real_Range_Specification (Def : Node_Id);
644 -- Given the type definition for a real type, this procedure processes and
645 -- checks the real range specification of this type definition if one is
646 -- present. If errors are found, error messages are posted, and the
647 -- Real_Range_Specification of Def is reset to Empty.
649 procedure Propagate_Default_Init_Cond_Attributes
650 (From_Typ : Entity_Id;
652 Parent_To_Derivation : Boolean := False;
653 Private_To_Full_View : Boolean := False);
654 -- Subsidiary to routines Build_Derived_Type and Process_Full_View. Inherit
655 -- all attributes related to pragma Default_Initial_Condition from From_Typ
656 -- to To_Typ. Flag Parent_To_Derivation should be set when the context is
657 -- the creation of a derived type. Flag Private_To_Full_View should be set
658 -- when processing both views of a private type.
660 procedure Record_Type_Declaration
664 -- Process a record type declaration (for both untagged and tagged
665 -- records). Parameters T and N are exactly like in procedure
666 -- Derived_Type_Declaration, except that no flag Is_Completion is needed
667 -- for this routine. If this is the completion of an incomplete type
668 -- declaration, Prev is the entity of the incomplete declaration, used for
669 -- cross-referencing. Otherwise Prev = T.
671 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id);
672 -- This routine is used to process the actual record type definition (both
673 -- for untagged and tagged records). Def is a record type definition node.
674 -- This procedure analyzes the components in this record type definition.
675 -- Prev_T is the entity for the enclosing record type. It is provided so
676 -- that its Has_Task flag can be set if any of the component have Has_Task
677 -- set. If the declaration is the completion of an incomplete type
678 -- declaration, Prev_T is the original incomplete type, whose full view is
681 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id);
682 -- Subsidiary to Build_Derived_Record_Type. For untagged records, we
683 -- build a copy of the declaration tree of the parent, and we create
684 -- independently the list of components for the derived type. Semantic
685 -- information uses the component entities, but record representation
686 -- clauses are validated on the declaration tree. This procedure replaces
687 -- discriminants and components in the declaration with those that have
688 -- been created by Inherit_Components.
690 procedure Set_Fixed_Range
695 -- Build a range node with the given bounds and set it as the Scalar_Range
696 -- of the given fixed-point type entity. Loc is the source location used
697 -- for the constructed range. See body for further details.
699 procedure Set_Scalar_Range_For_Subtype
703 -- This routine is used to set the scalar range field for a subtype given
704 -- Def_Id, the entity for the subtype, and R, the range expression for the
705 -- scalar range. Subt provides the parent subtype to be used to analyze,
706 -- resolve, and check the given range.
708 procedure Set_Default_SSO (T : Entity_Id);
709 -- T is the entity for an array or record being declared. This procedure
710 -- sets the flags SSO_Set_Low_By_Default/SSO_Set_High_By_Default according
711 -- to the setting of Opt.Default_SSO.
713 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id);
714 -- Create a new signed integer entity, and apply the constraint to obtain
715 -- the required first named subtype of this type.
717 procedure Set_Stored_Constraint_From_Discriminant_Constraint
719 -- E is some record type. This routine computes E's Stored_Constraint
720 -- from its Discriminant_Constraint.
722 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id);
723 -- Check that an entity in a list of progenitors is an interface,
724 -- emit error otherwise.
726 -----------------------
727 -- Access_Definition --
728 -----------------------
730 function Access_Definition
731 (Related_Nod : Node_Id;
732 N : Node_Id) return Entity_Id
734 Anon_Type : Entity_Id;
735 Anon_Scope : Entity_Id;
736 Desig_Type : Entity_Id;
737 Enclosing_Prot_Type : Entity_Id := Empty;
740 Check_SPARK_05_Restriction ("access type is not allowed", N);
742 if Is_Entry (Current_Scope)
743 and then Is_Task_Type (Etype (Scope (Current_Scope)))
745 Error_Msg_N ("task entries cannot have access parameters", N);
749 -- Ada 2005: For an object declaration the corresponding anonymous
750 -- type is declared in the current scope.
752 -- If the access definition is the return type of another access to
753 -- function, scope is the current one, because it is the one of the
754 -- current type declaration, except for the pathological case below.
756 if Nkind_In (Related_Nod, N_Object_Declaration,
757 N_Access_Function_Definition)
759 Anon_Scope := Current_Scope;
761 -- A pathological case: function returning access functions that
762 -- return access functions, etc. Each anonymous access type created
763 -- is in the enclosing scope of the outermost function.
770 while Nkind_In (Par, N_Access_Function_Definition,
776 if Nkind (Par) = N_Function_Specification then
777 Anon_Scope := Scope (Defining_Entity (Par));
781 -- For the anonymous function result case, retrieve the scope of the
782 -- function specification's associated entity rather than using the
783 -- current scope. The current scope will be the function itself if the
784 -- formal part is currently being analyzed, but will be the parent scope
785 -- in the case of a parameterless function, and we always want to use
786 -- the function's parent scope. Finally, if the function is a child
787 -- unit, we must traverse the tree to retrieve the proper entity.
789 elsif Nkind (Related_Nod) = N_Function_Specification
790 and then Nkind (Parent (N)) /= N_Parameter_Specification
792 -- If the current scope is a protected type, the anonymous access
793 -- is associated with one of the protected operations, and must
794 -- be available in the scope that encloses the protected declaration.
795 -- Otherwise the type is in the scope enclosing the subprogram.
797 -- If the function has formals, The return type of a subprogram
798 -- declaration is analyzed in the scope of the subprogram (see
799 -- Process_Formals) and thus the protected type, if present, is
800 -- the scope of the current function scope.
802 if Ekind (Current_Scope) = E_Protected_Type then
803 Enclosing_Prot_Type := Current_Scope;
805 elsif Ekind (Current_Scope) = E_Function
806 and then Ekind (Scope (Current_Scope)) = E_Protected_Type
808 Enclosing_Prot_Type := Scope (Current_Scope);
811 if Present (Enclosing_Prot_Type) then
812 Anon_Scope := Scope (Enclosing_Prot_Type);
815 Anon_Scope := Scope (Defining_Entity (Related_Nod));
818 -- For an access type definition, if the current scope is a child
819 -- unit it is the scope of the type.
821 elsif Is_Compilation_Unit (Current_Scope) then
822 Anon_Scope := Current_Scope;
824 -- For access formals, access components, and access discriminants, the
825 -- scope is that of the enclosing declaration,
828 Anon_Scope := Scope (Current_Scope);
833 (E_Anonymous_Access_Type, Related_Nod, Scope_Id => Anon_Scope);
836 and then Ada_Version >= Ada_2005
838 Error_Msg_N ("ALL is not permitted for anonymous access types", N);
841 -- Ada 2005 (AI-254): In case of anonymous access to subprograms call
842 -- the corresponding semantic routine
844 if Present (Access_To_Subprogram_Definition (N)) then
846 -- Compiler runtime units are compiled in Ada 2005 mode when building
847 -- the runtime library but must also be compilable in Ada 95 mode
848 -- (when bootstrapping the compiler).
850 Check_Compiler_Unit ("anonymous access to subprogram", N);
852 Access_Subprogram_Declaration
853 (T_Name => Anon_Type,
854 T_Def => Access_To_Subprogram_Definition (N));
856 if Ekind (Anon_Type) = E_Access_Protected_Subprogram_Type then
858 (Anon_Type, E_Anonymous_Access_Protected_Subprogram_Type);
860 Set_Ekind (Anon_Type, E_Anonymous_Access_Subprogram_Type);
863 Set_Can_Use_Internal_Rep
864 (Anon_Type, not Always_Compatible_Rep_On_Target);
866 -- If the anonymous access is associated with a protected operation,
867 -- create a reference to it after the enclosing protected definition
868 -- because the itype will be used in the subsequent bodies.
870 -- If the anonymous access itself is protected, a full type
871 -- declaratiton will be created for it, so that the equivalent
872 -- record type can be constructed. For further details, see
873 -- Replace_Anonymous_Access_To_Protected-Subprogram.
875 if Ekind (Current_Scope) = E_Protected_Type
876 and then not Protected_Present (Access_To_Subprogram_Definition (N))
878 Build_Itype_Reference (Anon_Type, Parent (Current_Scope));
884 Find_Type (Subtype_Mark (N));
885 Desig_Type := Entity (Subtype_Mark (N));
887 Set_Directly_Designated_Type (Anon_Type, Desig_Type);
888 Set_Etype (Anon_Type, Anon_Type);
890 -- Make sure the anonymous access type has size and alignment fields
891 -- set, as required by gigi. This is necessary in the case of the
892 -- Task_Body_Procedure.
894 if not Has_Private_Component (Desig_Type) then
895 Layout_Type (Anon_Type);
898 -- Ada 2005 (AI-231): Ada 2005 semantics for anonymous access differs
899 -- from Ada 95 semantics. In Ada 2005, anonymous access must specify if
900 -- the null value is allowed. In Ada 95 the null value is never allowed.
902 if Ada_Version >= Ada_2005 then
903 Set_Can_Never_Be_Null (Anon_Type, Null_Exclusion_Present (N));
905 Set_Can_Never_Be_Null (Anon_Type, True);
908 -- The anonymous access type is as public as the discriminated type or
909 -- subprogram that defines it. It is imported (for back-end purposes)
910 -- if the designated type is.
912 Set_Is_Public (Anon_Type, Is_Public (Scope (Anon_Type)));
914 -- Ada 2005 (AI-231): Propagate the access-constant attribute
916 Set_Is_Access_Constant (Anon_Type, Constant_Present (N));
918 -- The context is either a subprogram declaration, object declaration,
919 -- or an access discriminant, in a private or a full type declaration.
920 -- In the case of a subprogram, if the designated type is incomplete,
921 -- the operation will be a primitive operation of the full type, to be
922 -- updated subsequently. If the type is imported through a limited_with
923 -- clause, the subprogram is not a primitive operation of the type
924 -- (which is declared elsewhere in some other scope).
926 if Ekind (Desig_Type) = E_Incomplete_Type
927 and then not From_Limited_With (Desig_Type)
928 and then Is_Overloadable (Current_Scope)
930 Append_Elmt (Current_Scope, Private_Dependents (Desig_Type));
931 Set_Has_Delayed_Freeze (Current_Scope);
934 -- Ada 2005: If the designated type is an interface that may contain
935 -- tasks, create a Master entity for the declaration. This must be done
936 -- before expansion of the full declaration, because the declaration may
937 -- include an expression that is an allocator, whose expansion needs the
938 -- proper Master for the created tasks.
940 if Nkind (Related_Nod) = N_Object_Declaration and then Expander_Active
942 if Is_Interface (Desig_Type) and then Is_Limited_Record (Desig_Type)
944 Build_Class_Wide_Master (Anon_Type);
946 -- Similarly, if the type is an anonymous access that designates
947 -- tasks, create a master entity for it in the current context.
949 elsif Has_Task (Desig_Type) and then Comes_From_Source (Related_Nod)
951 Build_Master_Entity (Defining_Identifier (Related_Nod));
952 Build_Master_Renaming (Anon_Type);
956 -- For a private component of a protected type, it is imperative that
957 -- the back-end elaborate the type immediately after the protected
958 -- declaration, because this type will be used in the declarations
959 -- created for the component within each protected body, so we must
960 -- create an itype reference for it now.
962 if Nkind (Parent (Related_Nod)) = N_Protected_Definition then
963 Build_Itype_Reference (Anon_Type, Parent (Parent (Related_Nod)));
965 -- Similarly, if the access definition is the return result of a
966 -- function, create an itype reference for it because it will be used
967 -- within the function body. For a regular function that is not a
968 -- compilation unit, insert reference after the declaration. For a
969 -- protected operation, insert it after the enclosing protected type
970 -- declaration. In either case, do not create a reference for a type
971 -- obtained through a limited_with clause, because this would introduce
972 -- semantic dependencies.
974 -- Similarly, do not create a reference if the designated type is a
975 -- generic formal, because no use of it will reach the backend.
977 elsif Nkind (Related_Nod) = N_Function_Specification
978 and then not From_Limited_With (Desig_Type)
979 and then not Is_Generic_Type (Desig_Type)
981 if Present (Enclosing_Prot_Type) then
982 Build_Itype_Reference (Anon_Type, Parent (Enclosing_Prot_Type));
984 elsif Is_List_Member (Parent (Related_Nod))
985 and then Nkind (Parent (N)) /= N_Parameter_Specification
987 Build_Itype_Reference (Anon_Type, Parent (Related_Nod));
990 -- Finally, create an itype reference for an object declaration of an
991 -- anonymous access type. This is strictly necessary only for deferred
992 -- constants, but in any case will avoid out-of-scope problems in the
995 elsif Nkind (Related_Nod) = N_Object_Declaration then
996 Build_Itype_Reference (Anon_Type, Related_Nod);
1000 end Access_Definition;
1002 -----------------------------------
1003 -- Access_Subprogram_Declaration --
1004 -----------------------------------
1006 procedure Access_Subprogram_Declaration
1007 (T_Name : Entity_Id;
1010 procedure Check_For_Premature_Usage (Def : Node_Id);
1011 -- Check that type T_Name is not used, directly or recursively, as a
1012 -- parameter or a return type in Def. Def is either a subtype, an
1013 -- access_definition, or an access_to_subprogram_definition.
1015 -------------------------------
1016 -- Check_For_Premature_Usage --
1017 -------------------------------
1019 procedure Check_For_Premature_Usage (Def : Node_Id) is
1023 -- Check for a subtype mark
1025 if Nkind (Def) in N_Has_Etype then
1026 if Etype (Def) = T_Name then
1028 ("type& cannot be used before end of its declaration", Def);
1031 -- If this is not a subtype, then this is an access_definition
1033 elsif Nkind (Def) = N_Access_Definition then
1034 if Present (Access_To_Subprogram_Definition (Def)) then
1035 Check_For_Premature_Usage
1036 (Access_To_Subprogram_Definition (Def));
1038 Check_For_Premature_Usage (Subtype_Mark (Def));
1041 -- The only cases left are N_Access_Function_Definition and
1042 -- N_Access_Procedure_Definition.
1045 if Present (Parameter_Specifications (Def)) then
1046 Param := First (Parameter_Specifications (Def));
1047 while Present (Param) loop
1048 Check_For_Premature_Usage (Parameter_Type (Param));
1049 Param := Next (Param);
1053 if Nkind (Def) = N_Access_Function_Definition then
1054 Check_For_Premature_Usage (Result_Definition (Def));
1057 end Check_For_Premature_Usage;
1061 Formals : constant List_Id := Parameter_Specifications (T_Def);
1064 Desig_Type : constant Entity_Id :=
1065 Create_Itype (E_Subprogram_Type, Parent (T_Def));
1067 -- Start of processing for Access_Subprogram_Declaration
1070 Check_SPARK_05_Restriction ("access type is not allowed", T_Def);
1072 -- Associate the Itype node with the inner full-type declaration or
1073 -- subprogram spec or entry body. This is required to handle nested
1074 -- anonymous declarations. For example:
1077 -- (X : access procedure
1078 -- (Y : access procedure
1081 D_Ityp := Associated_Node_For_Itype (Desig_Type);
1082 while not (Nkind_In (D_Ityp, N_Full_Type_Declaration,
1083 N_Private_Type_Declaration,
1084 N_Private_Extension_Declaration,
1085 N_Procedure_Specification,
1086 N_Function_Specification,
1090 Nkind_In (D_Ityp, N_Object_Declaration,
1091 N_Object_Renaming_Declaration,
1092 N_Formal_Object_Declaration,
1093 N_Formal_Type_Declaration,
1094 N_Task_Type_Declaration,
1095 N_Protected_Type_Declaration))
1097 D_Ityp := Parent (D_Ityp);
1098 pragma Assert (D_Ityp /= Empty);
1101 Set_Associated_Node_For_Itype (Desig_Type, D_Ityp);
1103 if Nkind_In (D_Ityp, N_Procedure_Specification,
1104 N_Function_Specification)
1106 Set_Scope (Desig_Type, Scope (Defining_Entity (D_Ityp)));
1108 elsif Nkind_In (D_Ityp, N_Full_Type_Declaration,
1109 N_Object_Declaration,
1110 N_Object_Renaming_Declaration,
1111 N_Formal_Type_Declaration)
1113 Set_Scope (Desig_Type, Scope (Defining_Identifier (D_Ityp)));
1116 if Nkind (T_Def) = N_Access_Function_Definition then
1117 if Nkind (Result_Definition (T_Def)) = N_Access_Definition then
1119 Acc : constant Node_Id := Result_Definition (T_Def);
1122 if Present (Access_To_Subprogram_Definition (Acc))
1124 Protected_Present (Access_To_Subprogram_Definition (Acc))
1128 Replace_Anonymous_Access_To_Protected_Subprogram
1134 Access_Definition (T_Def, Result_Definition (T_Def)));
1139 Analyze (Result_Definition (T_Def));
1142 Typ : constant Entity_Id := Entity (Result_Definition (T_Def));
1145 -- If a null exclusion is imposed on the result type, then
1146 -- create a null-excluding itype (an access subtype) and use
1147 -- it as the function's Etype.
1149 if Is_Access_Type (Typ)
1150 and then Null_Exclusion_In_Return_Present (T_Def)
1152 Set_Etype (Desig_Type,
1153 Create_Null_Excluding_Itype
1155 Related_Nod => T_Def,
1156 Scope_Id => Current_Scope));
1159 if From_Limited_With (Typ) then
1161 -- AI05-151: Incomplete types are allowed in all basic
1162 -- declarations, including access to subprograms.
1164 if Ada_Version >= Ada_2012 then
1169 ("illegal use of incomplete type&",
1170 Result_Definition (T_Def), Typ);
1173 elsif Ekind (Current_Scope) = E_Package
1174 and then In_Private_Part (Current_Scope)
1176 if Ekind (Typ) = E_Incomplete_Type then
1177 Append_Elmt (Desig_Type, Private_Dependents (Typ));
1179 elsif Is_Class_Wide_Type (Typ)
1180 and then Ekind (Etype (Typ)) = E_Incomplete_Type
1183 (Desig_Type, Private_Dependents (Etype (Typ)));
1187 Set_Etype (Desig_Type, Typ);
1192 if not (Is_Type (Etype (Desig_Type))) then
1194 ("expect type in function specification",
1195 Result_Definition (T_Def));
1199 Set_Etype (Desig_Type, Standard_Void_Type);
1202 if Present (Formals) then
1203 Push_Scope (Desig_Type);
1205 -- Some special tests here. These special tests can be removed
1206 -- if and when Itypes always have proper parent pointers to their
1209 -- Special test 1) Link defining_identifier of formals. Required by
1210 -- First_Formal to provide its functionality.
1216 F := First (Formals);
1218 -- In ASIS mode, the access_to_subprogram may be analyzed twice,
1219 -- when it is part of an unconstrained type and subtype expansion
1220 -- is disabled. To avoid back-end problems with shared profiles,
1221 -- use previous subprogram type as the designated type, and then
1222 -- remove scope added above.
1224 if ASIS_Mode and then Present (Scope (Defining_Identifier (F)))
1226 Set_Etype (T_Name, T_Name);
1227 Init_Size_Align (T_Name);
1228 Set_Directly_Designated_Type (T_Name,
1229 Scope (Defining_Identifier (F)));
1234 while Present (F) loop
1235 if No (Parent (Defining_Identifier (F))) then
1236 Set_Parent (Defining_Identifier (F), F);
1243 Process_Formals (Formals, Parent (T_Def));
1245 -- Special test 2) End_Scope requires that the parent pointer be set
1246 -- to something reasonable, but Itypes don't have parent pointers. So
1247 -- we set it and then unset it ???
1249 Set_Parent (Desig_Type, T_Name);
1251 Set_Parent (Desig_Type, Empty);
1254 -- Check for premature usage of the type being defined
1256 Check_For_Premature_Usage (T_Def);
1258 -- The return type and/or any parameter type may be incomplete. Mark the
1259 -- subprogram_type as depending on the incomplete type, so that it can
1260 -- be updated when the full type declaration is seen. This only applies
1261 -- to incomplete types declared in some enclosing scope, not to limited
1262 -- views from other packages.
1264 -- Prior to Ada 2012, access to functions can only have in_parameters.
1266 if Present (Formals) then
1267 Formal := First_Formal (Desig_Type);
1268 while Present (Formal) loop
1269 if Ekind (Formal) /= E_In_Parameter
1270 and then Nkind (T_Def) = N_Access_Function_Definition
1271 and then Ada_Version < Ada_2012
1273 Error_Msg_N ("functions can only have IN parameters", Formal);
1276 if Ekind (Etype (Formal)) = E_Incomplete_Type
1277 and then In_Open_Scopes (Scope (Etype (Formal)))
1279 Append_Elmt (Desig_Type, Private_Dependents (Etype (Formal)));
1280 Set_Has_Delayed_Freeze (Desig_Type);
1283 Next_Formal (Formal);
1287 -- Check whether an indirect call without actuals may be possible. This
1288 -- is used when resolving calls whose result is then indexed.
1290 May_Need_Actuals (Desig_Type);
1292 -- If the return type is incomplete, this is legal as long as the type
1293 -- is declared in the current scope and will be completed in it (rather
1294 -- than being part of limited view).
1296 if Ekind (Etype (Desig_Type)) = E_Incomplete_Type
1297 and then not Has_Delayed_Freeze (Desig_Type)
1298 and then In_Open_Scopes (Scope (Etype (Desig_Type)))
1300 Append_Elmt (Desig_Type, Private_Dependents (Etype (Desig_Type)));
1301 Set_Has_Delayed_Freeze (Desig_Type);
1304 Check_Delayed_Subprogram (Desig_Type);
1306 if Protected_Present (T_Def) then
1307 Set_Ekind (T_Name, E_Access_Protected_Subprogram_Type);
1308 Set_Convention (Desig_Type, Convention_Protected);
1310 Set_Ekind (T_Name, E_Access_Subprogram_Type);
1313 Set_Can_Use_Internal_Rep (T_Name, not Always_Compatible_Rep_On_Target);
1315 Set_Etype (T_Name, T_Name);
1316 Init_Size_Align (T_Name);
1317 Set_Directly_Designated_Type (T_Name, Desig_Type);
1319 Generate_Reference_To_Formals (T_Name);
1321 -- Ada 2005 (AI-231): Propagate the null-excluding attribute
1323 Set_Can_Never_Be_Null (T_Name, Null_Exclusion_Present (T_Def));
1325 Check_Restriction (No_Access_Subprograms, T_Def);
1326 end Access_Subprogram_Declaration;
1328 ----------------------------
1329 -- Access_Type_Declaration --
1330 ----------------------------
1332 procedure Access_Type_Declaration (T : Entity_Id; Def : Node_Id) is
1333 P : constant Node_Id := Parent (Def);
1334 S : constant Node_Id := Subtype_Indication (Def);
1336 Full_Desig : Entity_Id;
1339 Check_SPARK_05_Restriction ("access type is not allowed", Def);
1341 -- Check for permissible use of incomplete type
1343 if Nkind (S) /= N_Subtype_Indication then
1346 if Ekind (Root_Type (Entity (S))) = E_Incomplete_Type then
1347 Set_Directly_Designated_Type (T, Entity (S));
1349 -- If the designated type is a limited view, we cannot tell if
1350 -- the full view contains tasks, and there is no way to handle
1351 -- that full view in a client. We create a master entity for the
1352 -- scope, which will be used when a client determines that one
1355 if From_Limited_With (Entity (S))
1356 and then not Is_Class_Wide_Type (Entity (S))
1358 Set_Ekind (T, E_Access_Type);
1359 Build_Master_Entity (T);
1360 Build_Master_Renaming (T);
1364 Set_Directly_Designated_Type (T, Process_Subtype (S, P, T, 'P'));
1367 -- If the access definition is of the form: ACCESS NOT NULL ..
1368 -- the subtype indication must be of an access type. Create
1369 -- a null-excluding subtype of it.
1371 if Null_Excluding_Subtype (Def) then
1372 if not Is_Access_Type (Entity (S)) then
1373 Error_Msg_N ("null exclusion must apply to access type", Def);
1377 Loc : constant Source_Ptr := Sloc (S);
1379 Nam : constant Entity_Id := Make_Temporary (Loc, 'S');
1383 Make_Subtype_Declaration (Loc,
1384 Defining_Identifier => Nam,
1385 Subtype_Indication =>
1386 New_Occurrence_Of (Entity (S), Loc));
1387 Set_Null_Exclusion_Present (Decl);
1388 Insert_Before (Parent (Def), Decl);
1390 Set_Entity (S, Nam);
1396 Set_Directly_Designated_Type (T,
1397 Process_Subtype (S, P, T, 'P'));
1400 if All_Present (Def) or Constant_Present (Def) then
1401 Set_Ekind (T, E_General_Access_Type);
1403 Set_Ekind (T, E_Access_Type);
1406 Full_Desig := Designated_Type (T);
1408 if Base_Type (Full_Desig) = T then
1409 Error_Msg_N ("access type cannot designate itself", S);
1411 -- In Ada 2005, the type may have a limited view through some unit in
1412 -- its own context, allowing the following circularity that cannot be
1413 -- detected earlier.
1415 elsif Is_Class_Wide_Type (Full_Desig) and then Etype (Full_Desig) = T
1418 ("access type cannot designate its own classwide type", S);
1420 -- Clean up indication of tagged status to prevent cascaded errors
1422 Set_Is_Tagged_Type (T, False);
1427 -- If the type has appeared already in a with_type clause, it is frozen
1428 -- and the pointer size is already set. Else, initialize.
1430 if not From_Limited_With (T) then
1431 Init_Size_Align (T);
1434 -- Note that Has_Task is always false, since the access type itself
1435 -- is not a task type. See Einfo for more description on this point.
1436 -- Exactly the same consideration applies to Has_Controlled_Component
1437 -- and to Has_Protected.
1439 Set_Has_Task (T, False);
1440 Set_Has_Controlled_Component (T, False);
1441 Set_Has_Protected (T, False);
1443 -- Initialize field Finalization_Master explicitly to Empty, to avoid
1444 -- problems where an incomplete view of this entity has been previously
1445 -- established by a limited with and an overlaid version of this field
1446 -- (Stored_Constraint) was initialized for the incomplete view.
1448 -- This reset is performed in most cases except where the access type
1449 -- has been created for the purposes of allocating or deallocating a
1450 -- build-in-place object. Such access types have explicitly set pools
1451 -- and finalization masters.
1453 if No (Associated_Storage_Pool (T)) then
1454 Set_Finalization_Master (T, Empty);
1457 -- Ada 2005 (AI-231): Propagate the null-excluding and access-constant
1460 Set_Can_Never_Be_Null (T, Null_Exclusion_Present (Def));
1461 Set_Is_Access_Constant (T, Constant_Present (Def));
1462 end Access_Type_Declaration;
1464 ----------------------------------
1465 -- Add_Interface_Tag_Components --
1466 ----------------------------------
1468 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id) is
1469 Loc : constant Source_Ptr := Sloc (N);
1473 procedure Add_Tag (Iface : Entity_Id);
1474 -- Add tag for one of the progenitor interfaces
1480 procedure Add_Tag (Iface : Entity_Id) is
1487 pragma Assert (Is_Tagged_Type (Iface) and then Is_Interface (Iface));
1489 -- This is a reasonable place to propagate predicates
1491 if Has_Predicates (Iface) then
1492 Set_Has_Predicates (Typ);
1496 Make_Component_Definition (Loc,
1497 Aliased_Present => True,
1498 Subtype_Indication =>
1499 New_Occurrence_Of (RTE (RE_Interface_Tag), Loc));
1501 Tag := Make_Temporary (Loc, 'V');
1504 Make_Component_Declaration (Loc,
1505 Defining_Identifier => Tag,
1506 Component_Definition => Def);
1508 Analyze_Component_Declaration (Decl);
1510 Set_Analyzed (Decl);
1511 Set_Ekind (Tag, E_Component);
1513 Set_Is_Aliased (Tag);
1514 Set_Related_Type (Tag, Iface);
1515 Init_Component_Location (Tag);
1517 pragma Assert (Is_Frozen (Iface));
1519 Set_DT_Entry_Count (Tag,
1520 DT_Entry_Count (First_Entity (Iface)));
1522 if No (Last_Tag) then
1525 Insert_After (Last_Tag, Decl);
1530 -- If the ancestor has discriminants we need to give special support
1531 -- to store the offset_to_top value of the secondary dispatch tables.
1532 -- For this purpose we add a supplementary component just after the
1533 -- field that contains the tag associated with each secondary DT.
1535 if Typ /= Etype (Typ) and then Has_Discriminants (Etype (Typ)) then
1537 Make_Component_Definition (Loc,
1538 Subtype_Indication =>
1539 New_Occurrence_Of (RTE (RE_Storage_Offset), Loc));
1541 Offset := Make_Temporary (Loc, 'V');
1544 Make_Component_Declaration (Loc,
1545 Defining_Identifier => Offset,
1546 Component_Definition => Def);
1548 Analyze_Component_Declaration (Decl);
1550 Set_Analyzed (Decl);
1551 Set_Ekind (Offset, E_Component);
1552 Set_Is_Aliased (Offset);
1553 Set_Related_Type (Offset, Iface);
1554 Init_Component_Location (Offset);
1555 Insert_After (Last_Tag, Decl);
1566 -- Start of processing for Add_Interface_Tag_Components
1569 if not RTE_Available (RE_Interface_Tag) then
1571 ("(Ada 2005) interface types not supported by this run-time!",
1576 if Ekind (Typ) /= E_Record_Type
1577 or else (Is_Concurrent_Record_Type (Typ)
1578 and then Is_Empty_List (Abstract_Interface_List (Typ)))
1579 or else (not Is_Concurrent_Record_Type (Typ)
1580 and then No (Interfaces (Typ))
1581 and then Is_Empty_Elmt_List (Interfaces (Typ)))
1586 -- Find the current last tag
1588 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1589 Ext := Record_Extension_Part (Type_Definition (N));
1591 pragma Assert (Nkind (Type_Definition (N)) = N_Record_Definition);
1592 Ext := Type_Definition (N);
1597 if not (Present (Component_List (Ext))) then
1598 Set_Null_Present (Ext, False);
1600 Set_Component_List (Ext,
1601 Make_Component_List (Loc,
1602 Component_Items => L,
1603 Null_Present => False));
1605 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1606 L := Component_Items
1608 (Record_Extension_Part
1609 (Type_Definition (N))));
1611 L := Component_Items
1613 (Type_Definition (N)));
1616 -- Find the last tag component
1619 while Present (Comp) loop
1620 if Nkind (Comp) = N_Component_Declaration
1621 and then Is_Tag (Defining_Identifier (Comp))
1630 -- At this point L references the list of components and Last_Tag
1631 -- references the current last tag (if any). Now we add the tag
1632 -- corresponding with all the interfaces that are not implemented
1635 if Present (Interfaces (Typ)) then
1636 Elmt := First_Elmt (Interfaces (Typ));
1637 while Present (Elmt) loop
1638 Add_Tag (Node (Elmt));
1642 end Add_Interface_Tag_Components;
1644 -------------------------------------
1645 -- Add_Internal_Interface_Entities --
1646 -------------------------------------
1648 procedure Add_Internal_Interface_Entities (Tagged_Type : Entity_Id) is
1651 Iface_Elmt : Elmt_Id;
1652 Iface_Prim : Entity_Id;
1653 Ifaces_List : Elist_Id;
1654 New_Subp : Entity_Id := Empty;
1656 Restore_Scope : Boolean := False;
1659 pragma Assert (Ada_Version >= Ada_2005
1660 and then Is_Record_Type (Tagged_Type)
1661 and then Is_Tagged_Type (Tagged_Type)
1662 and then Has_Interfaces (Tagged_Type)
1663 and then not Is_Interface (Tagged_Type));
1665 -- Ensure that the internal entities are added to the scope of the type
1667 if Scope (Tagged_Type) /= Current_Scope then
1668 Push_Scope (Scope (Tagged_Type));
1669 Restore_Scope := True;
1672 Collect_Interfaces (Tagged_Type, Ifaces_List);
1674 Iface_Elmt := First_Elmt (Ifaces_List);
1675 while Present (Iface_Elmt) loop
1676 Iface := Node (Iface_Elmt);
1678 -- Originally we excluded here from this processing interfaces that
1679 -- are parents of Tagged_Type because their primitives are located
1680 -- in the primary dispatch table (and hence no auxiliary internal
1681 -- entities are required to handle secondary dispatch tables in such
1682 -- case). However, these auxiliary entities are also required to
1683 -- handle derivations of interfaces in formals of generics (see
1684 -- Derive_Subprograms).
1686 Elmt := First_Elmt (Primitive_Operations (Iface));
1687 while Present (Elmt) loop
1688 Iface_Prim := Node (Elmt);
1690 if not Is_Predefined_Dispatching_Operation (Iface_Prim) then
1692 Find_Primitive_Covering_Interface
1693 (Tagged_Type => Tagged_Type,
1694 Iface_Prim => Iface_Prim);
1696 if No (Prim) and then Serious_Errors_Detected > 0 then
1700 pragma Assert (Present (Prim));
1702 -- Ada 2012 (AI05-0197): If the name of the covering primitive
1703 -- differs from the name of the interface primitive then it is
1704 -- a private primitive inherited from a parent type. In such
1705 -- case, given that Tagged_Type covers the interface, the
1706 -- inherited private primitive becomes visible. For such
1707 -- purpose we add a new entity that renames the inherited
1708 -- private primitive.
1710 if Chars (Prim) /= Chars (Iface_Prim) then
1711 pragma Assert (Has_Suffix (Prim, 'P'));
1713 (New_Subp => New_Subp,
1714 Parent_Subp => Iface_Prim,
1715 Derived_Type => Tagged_Type,
1716 Parent_Type => Iface);
1717 Set_Alias (New_Subp, Prim);
1718 Set_Is_Abstract_Subprogram
1719 (New_Subp, Is_Abstract_Subprogram (Prim));
1723 (New_Subp => New_Subp,
1724 Parent_Subp => Iface_Prim,
1725 Derived_Type => Tagged_Type,
1726 Parent_Type => Iface);
1728 -- Ada 2005 (AI-251): Decorate internal entity Iface_Subp
1729 -- associated with interface types. These entities are
1730 -- only registered in the list of primitives of its
1731 -- corresponding tagged type because they are only used
1732 -- to fill the contents of the secondary dispatch tables.
1733 -- Therefore they are removed from the homonym chains.
1735 Set_Is_Hidden (New_Subp);
1736 Set_Is_Internal (New_Subp);
1737 Set_Alias (New_Subp, Prim);
1738 Set_Is_Abstract_Subprogram
1739 (New_Subp, Is_Abstract_Subprogram (Prim));
1740 Set_Interface_Alias (New_Subp, Iface_Prim);
1742 -- If the returned type is an interface then propagate it to
1743 -- the returned type. Needed by the thunk to generate the code
1744 -- which displaces "this" to reference the corresponding
1745 -- secondary dispatch table in the returned object.
1747 if Is_Interface (Etype (Iface_Prim)) then
1748 Set_Etype (New_Subp, Etype (Iface_Prim));
1751 -- Internal entities associated with interface types are only
1752 -- registered in the list of primitives of the tagged type.
1753 -- They are only used to fill the contents of the secondary
1754 -- dispatch tables. Therefore they are not needed in the
1757 Remove_Homonym (New_Subp);
1759 -- Hidden entities associated with interfaces must have set
1760 -- the Has_Delay_Freeze attribute to ensure that, in case
1761 -- of locally defined tagged types (or compiling with static
1762 -- dispatch tables generation disabled) the corresponding
1763 -- entry of the secondary dispatch table is filled when such
1764 -- an entity is frozen. This is an expansion activity that must
1765 -- be suppressed for ASIS because it leads to gigi elaboration
1766 -- issues in annotate mode.
1768 if not ASIS_Mode then
1769 Set_Has_Delayed_Freeze (New_Subp);
1777 Next_Elmt (Iface_Elmt);
1780 if Restore_Scope then
1783 end Add_Internal_Interface_Entities;
1785 -----------------------------------
1786 -- Analyze_Component_Declaration --
1787 -----------------------------------
1789 procedure Analyze_Component_Declaration (N : Node_Id) is
1790 Loc : constant Source_Ptr := Sloc (Component_Definition (N));
1791 Id : constant Entity_Id := Defining_Identifier (N);
1792 E : constant Node_Id := Expression (N);
1793 Typ : constant Node_Id :=
1794 Subtype_Indication (Component_Definition (N));
1798 function Contains_POC (Constr : Node_Id) return Boolean;
1799 -- Determines whether a constraint uses the discriminant of a record
1800 -- type thus becoming a per-object constraint (POC).
1802 function Is_Known_Limited (Typ : Entity_Id) return Boolean;
1803 -- Typ is the type of the current component, check whether this type is
1804 -- a limited type. Used to validate declaration against that of
1805 -- enclosing record.
1811 function Contains_POC (Constr : Node_Id) return Boolean is
1813 -- Prevent cascaded errors
1815 if Error_Posted (Constr) then
1819 case Nkind (Constr) is
1820 when N_Attribute_Reference =>
1821 return Attribute_Name (Constr) = Name_Access
1822 and then Prefix (Constr) = Scope (Entity (Prefix (Constr)));
1824 when N_Discriminant_Association =>
1825 return Denotes_Discriminant (Expression (Constr));
1827 when N_Identifier =>
1828 return Denotes_Discriminant (Constr);
1830 when N_Index_Or_Discriminant_Constraint =>
1835 IDC := First (Constraints (Constr));
1836 while Present (IDC) loop
1838 -- One per-object constraint is sufficient
1840 if Contains_POC (IDC) then
1851 return Denotes_Discriminant (Low_Bound (Constr))
1853 Denotes_Discriminant (High_Bound (Constr));
1855 when N_Range_Constraint =>
1856 return Denotes_Discriminant (Range_Expression (Constr));
1864 ----------------------
1865 -- Is_Known_Limited --
1866 ----------------------
1868 function Is_Known_Limited (Typ : Entity_Id) return Boolean is
1869 P : constant Entity_Id := Etype (Typ);
1870 R : constant Entity_Id := Root_Type (Typ);
1873 if Is_Limited_Record (Typ) then
1876 -- If the root type is limited (and not a limited interface)
1877 -- so is the current type
1879 elsif Is_Limited_Record (R)
1880 and then (not Is_Interface (R) or else not Is_Limited_Interface (R))
1884 -- Else the type may have a limited interface progenitor, but a
1885 -- limited record parent.
1887 elsif R /= P and then Is_Limited_Record (P) then
1893 end Is_Known_Limited;
1895 -- Start of processing for Analyze_Component_Declaration
1898 Generate_Definition (Id);
1901 if Present (Typ) then
1902 T := Find_Type_Of_Object
1903 (Subtype_Indication (Component_Definition (N)), N);
1905 if not Nkind_In (Typ, N_Identifier, N_Expanded_Name) then
1906 Check_SPARK_05_Restriction ("subtype mark required", Typ);
1909 -- Ada 2005 (AI-230): Access Definition case
1912 pragma Assert (Present
1913 (Access_Definition (Component_Definition (N))));
1915 T := Access_Definition
1917 N => Access_Definition (Component_Definition (N)));
1918 Set_Is_Local_Anonymous_Access (T);
1920 -- Ada 2005 (AI-254)
1922 if Present (Access_To_Subprogram_Definition
1923 (Access_Definition (Component_Definition (N))))
1924 and then Protected_Present (Access_To_Subprogram_Definition
1926 (Component_Definition (N))))
1928 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1932 -- If the subtype is a constrained subtype of the enclosing record,
1933 -- (which must have a partial view) the back-end does not properly
1934 -- handle the recursion. Rewrite the component declaration with an
1935 -- explicit subtype indication, which is acceptable to Gigi. We can copy
1936 -- the tree directly because side effects have already been removed from
1937 -- discriminant constraints.
1939 if Ekind (T) = E_Access_Subtype
1940 and then Is_Entity_Name (Subtype_Indication (Component_Definition (N)))
1941 and then Comes_From_Source (T)
1942 and then Nkind (Parent (T)) = N_Subtype_Declaration
1943 and then Etype (Directly_Designated_Type (T)) = Current_Scope
1946 (Subtype_Indication (Component_Definition (N)),
1947 New_Copy_Tree (Subtype_Indication (Parent (T))));
1948 T := Find_Type_Of_Object
1949 (Subtype_Indication (Component_Definition (N)), N);
1952 -- If the component declaration includes a default expression, then we
1953 -- check that the component is not of a limited type (RM 3.7(5)),
1954 -- and do the special preanalysis of the expression (see section on
1955 -- "Handling of Default and Per-Object Expressions" in the spec of
1959 Check_SPARK_05_Restriction ("default expression is not allowed", E);
1960 Preanalyze_Default_Expression (E, T);
1961 Check_Initialization (T, E);
1963 if Ada_Version >= Ada_2005
1964 and then Ekind (T) = E_Anonymous_Access_Type
1965 and then Etype (E) /= Any_Type
1967 -- Check RM 3.9.2(9): "if the expected type for an expression is
1968 -- an anonymous access-to-specific tagged type, then the object
1969 -- designated by the expression shall not be dynamically tagged
1970 -- unless it is a controlling operand in a call on a dispatching
1973 if Is_Tagged_Type (Directly_Designated_Type (T))
1975 Ekind (Directly_Designated_Type (T)) /= E_Class_Wide_Type
1977 Ekind (Directly_Designated_Type (Etype (E))) =
1981 ("access to specific tagged type required (RM 3.9.2(9))", E);
1984 -- (Ada 2005: AI-230): Accessibility check for anonymous
1987 if Type_Access_Level (Etype (E)) >
1988 Deepest_Type_Access_Level (T)
1991 ("expression has deeper access level than component " &
1992 "(RM 3.10.2 (12.2))", E);
1995 -- The initialization expression is a reference to an access
1996 -- discriminant. The type of the discriminant is always deeper
1997 -- than any access type.
1999 if Ekind (Etype (E)) = E_Anonymous_Access_Type
2000 and then Is_Entity_Name (E)
2001 and then Ekind (Entity (E)) = E_In_Parameter
2002 and then Present (Discriminal_Link (Entity (E)))
2005 ("discriminant has deeper accessibility level than target",
2011 -- The parent type may be a private view with unknown discriminants,
2012 -- and thus unconstrained. Regular components must be constrained.
2014 if not Is_Definite_Subtype (T) and then Chars (Id) /= Name_uParent then
2015 if Is_Class_Wide_Type (T) then
2017 ("class-wide subtype with unknown discriminants" &
2018 " in component declaration",
2019 Subtype_Indication (Component_Definition (N)));
2022 ("unconstrained subtype in component declaration",
2023 Subtype_Indication (Component_Definition (N)));
2026 -- Components cannot be abstract, except for the special case of
2027 -- the _Parent field (case of extending an abstract tagged type)
2029 elsif Is_Abstract_Type (T) and then Chars (Id) /= Name_uParent then
2030 Error_Msg_N ("type of a component cannot be abstract", N);
2034 Set_Is_Aliased (Id, Aliased_Present (Component_Definition (N)));
2036 -- The component declaration may have a per-object constraint, set
2037 -- the appropriate flag in the defining identifier of the subtype.
2039 if Present (Subtype_Indication (Component_Definition (N))) then
2041 Sindic : constant Node_Id :=
2042 Subtype_Indication (Component_Definition (N));
2044 if Nkind (Sindic) = N_Subtype_Indication
2045 and then Present (Constraint (Sindic))
2046 and then Contains_POC (Constraint (Sindic))
2048 Set_Has_Per_Object_Constraint (Id);
2053 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
2054 -- out some static checks.
2056 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
2057 Null_Exclusion_Static_Checks (N);
2060 -- If this component is private (or depends on a private type), flag the
2061 -- record type to indicate that some operations are not available.
2063 P := Private_Component (T);
2067 -- Check for circular definitions
2069 if P = Any_Type then
2070 Set_Etype (Id, Any_Type);
2072 -- There is a gap in the visibility of operations only if the
2073 -- component type is not defined in the scope of the record type.
2075 elsif Scope (P) = Scope (Current_Scope) then
2078 elsif Is_Limited_Type (P) then
2079 Set_Is_Limited_Composite (Current_Scope);
2082 Set_Is_Private_Composite (Current_Scope);
2087 and then Is_Limited_Type (T)
2088 and then Chars (Id) /= Name_uParent
2089 and then Is_Tagged_Type (Current_Scope)
2091 if Is_Derived_Type (Current_Scope)
2092 and then not Is_Known_Limited (Current_Scope)
2095 ("extension of nonlimited type cannot have limited components",
2098 if Is_Interface (Root_Type (Current_Scope)) then
2100 ("\limitedness is not inherited from limited interface", N);
2101 Error_Msg_N ("\add LIMITED to type indication", N);
2104 Explain_Limited_Type (T, N);
2105 Set_Etype (Id, Any_Type);
2106 Set_Is_Limited_Composite (Current_Scope, False);
2108 elsif not Is_Derived_Type (Current_Scope)
2109 and then not Is_Limited_Record (Current_Scope)
2110 and then not Is_Concurrent_Type (Current_Scope)
2113 ("nonlimited tagged type cannot have limited components", N);
2114 Explain_Limited_Type (T, N);
2115 Set_Etype (Id, Any_Type);
2116 Set_Is_Limited_Composite (Current_Scope, False);
2120 -- If the component is an unconstrained task or protected type with
2121 -- discriminants, the component and the enclosing record are limited
2122 -- and the component is constrained by its default values. Compute
2123 -- its actual subtype, else it may be allocated the maximum size by
2124 -- the backend, and possibly overflow.
2126 if Is_Concurrent_Type (T)
2127 and then not Is_Constrained (T)
2128 and then Has_Discriminants (T)
2129 and then not Has_Discriminants (Current_Scope)
2132 Act_T : constant Entity_Id := Build_Default_Subtype (T, N);
2135 Set_Etype (Id, Act_T);
2137 -- Rewrite component definition to use the constrained subtype
2139 Rewrite (Component_Definition (N),
2140 Make_Component_Definition (Loc,
2141 Subtype_Indication => New_Occurrence_Of (Act_T, Loc)));
2145 Set_Original_Record_Component (Id, Id);
2147 if Has_Aspects (N) then
2148 Analyze_Aspect_Specifications (N, Id);
2151 Analyze_Dimension (N);
2152 end Analyze_Component_Declaration;
2154 --------------------------
2155 -- Analyze_Declarations --
2156 --------------------------
2158 procedure Analyze_Declarations (L : List_Id) is
2161 procedure Adjust_Decl;
2162 -- Adjust Decl not to include implicit label declarations, since these
2163 -- have strange Sloc values that result in elaboration check problems.
2164 -- (They have the sloc of the label as found in the source, and that
2165 -- is ahead of the current declarative part).
2167 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id);
2168 -- Determine whether Body_Decl denotes the body of a late controlled
2169 -- primitive (either Initialize, Adjust or Finalize). If this is the
2170 -- case, add a proper spec if the body lacks one. The spec is inserted
2171 -- before Body_Decl and immedately analyzed.
2173 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id);
2174 -- Spec_Id is the entity of a package that may define abstract states.
2175 -- If the states have visible refinement, remove the visibility of each
2176 -- constituent at the end of the package body declarations.
2182 procedure Adjust_Decl is
2184 while Present (Prev (Decl))
2185 and then Nkind (Decl) = N_Implicit_Label_Declaration
2191 --------------------------------------
2192 -- Handle_Late_Controlled_Primitive --
2193 --------------------------------------
2195 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id) is
2196 Body_Spec : constant Node_Id := Specification (Body_Decl);
2197 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2198 Loc : constant Source_Ptr := Sloc (Body_Id);
2199 Params : constant List_Id :=
2200 Parameter_Specifications (Body_Spec);
2202 Spec_Id : Entity_Id;
2206 -- Consider only procedure bodies whose name matches one of the three
2207 -- controlled primitives.
2209 if Nkind (Body_Spec) /= N_Procedure_Specification
2210 or else not Nam_In (Chars (Body_Id), Name_Adjust,
2216 -- A controlled primitive must have exactly one formal which is not
2217 -- an anonymous access type.
2219 elsif List_Length (Params) /= 1 then
2223 Typ := Parameter_Type (First (Params));
2225 if Nkind (Typ) = N_Access_Definition then
2231 -- The type of the formal must be derived from [Limited_]Controlled
2233 if not Is_Controlled (Entity (Typ)) then
2237 -- Check whether a specification exists for this body. We do not
2238 -- analyze the spec of the body in full, because it will be analyzed
2239 -- again when the body is properly analyzed, and we cannot create
2240 -- duplicate entries in the formals chain. We look for an explicit
2241 -- specification because the body may be an overriding operation and
2242 -- an inherited spec may be present.
2244 Spec_Id := Current_Entity (Body_Id);
2246 while Present (Spec_Id) loop
2247 if Ekind_In (Spec_Id, E_Procedure, E_Generic_Procedure)
2248 and then Scope (Spec_Id) = Current_Scope
2249 and then Present (First_Formal (Spec_Id))
2250 and then No (Next_Formal (First_Formal (Spec_Id)))
2251 and then Etype (First_Formal (Spec_Id)) = Entity (Typ)
2252 and then Comes_From_Source (Spec_Id)
2257 Spec_Id := Homonym (Spec_Id);
2260 -- At this point the body is known to be a late controlled primitive.
2261 -- Generate a matching spec and insert it before the body. Note the
2262 -- use of Copy_Separate_Tree - we want an entirely separate semantic
2263 -- tree in this case.
2265 Spec := Copy_Separate_Tree (Body_Spec);
2267 -- Ensure that the subprogram declaration does not inherit the null
2268 -- indicator from the body as we now have a proper spec/body pair.
2270 Set_Null_Present (Spec, False);
2272 Insert_Before_And_Analyze (Body_Decl,
2273 Make_Subprogram_Declaration (Loc, Specification => Spec));
2274 end Handle_Late_Controlled_Primitive;
2276 --------------------------------
2277 -- Remove_Visible_Refinements --
2278 --------------------------------
2280 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id) is
2281 State_Elmt : Elmt_Id;
2283 if Present (Abstract_States (Spec_Id)) then
2284 State_Elmt := First_Elmt (Abstract_States (Spec_Id));
2285 while Present (State_Elmt) loop
2286 Set_Has_Visible_Refinement (Node (State_Elmt), False);
2287 Next_Elmt (State_Elmt);
2290 end Remove_Visible_Refinements;
2294 Context : Node_Id := Empty;
2295 Freeze_From : Entity_Id := Empty;
2296 Next_Decl : Node_Id;
2298 Body_Seen : Boolean := False;
2299 -- Flag set when the first body [stub] is encountered
2301 -- Start of processing for Analyze_Declarations
2304 if Restriction_Check_Required (SPARK_05) then
2305 Check_Later_Vs_Basic_Declarations (L, During_Parsing => False);
2309 while Present (Decl) loop
2311 -- Package spec cannot contain a package declaration in SPARK
2313 if Nkind (Decl) = N_Package_Declaration
2314 and then Nkind (Parent (L)) = N_Package_Specification
2316 Check_SPARK_05_Restriction
2317 ("package specification cannot contain a package declaration",
2321 -- Complete analysis of declaration
2324 Next_Decl := Next (Decl);
2326 if No (Freeze_From) then
2327 Freeze_From := First_Entity (Current_Scope);
2330 -- At the end of a declarative part, freeze remaining entities
2331 -- declared in it. The end of the visible declarations of package
2332 -- specification is not the end of a declarative part if private
2333 -- declarations are present. The end of a package declaration is a
2334 -- freezing point only if it a library package. A task definition or
2335 -- protected type definition is not a freeze point either. Finally,
2336 -- we do not freeze entities in generic scopes, because there is no
2337 -- code generated for them and freeze nodes will be generated for
2340 -- The end of a package instantiation is not a freeze point, but
2341 -- for now we make it one, because the generic body is inserted
2342 -- (currently) immediately after. Generic instantiations will not
2343 -- be a freeze point once delayed freezing of bodies is implemented.
2344 -- (This is needed in any case for early instantiations ???).
2346 if No (Next_Decl) then
2347 if Nkind_In (Parent (L), N_Component_List,
2349 N_Protected_Definition)
2353 elsif Nkind (Parent (L)) /= N_Package_Specification then
2354 if Nkind (Parent (L)) = N_Package_Body then
2355 Freeze_From := First_Entity (Current_Scope);
2358 -- There may have been several freezing points previously,
2359 -- for example object declarations or subprogram bodies, but
2360 -- at the end of a declarative part we check freezing from
2361 -- the beginning, even though entities may already be frozen,
2362 -- in order to perform visibility checks on delayed aspects.
2365 Freeze_All (First_Entity (Current_Scope), Decl);
2366 Freeze_From := Last_Entity (Current_Scope);
2368 elsif Scope (Current_Scope) /= Standard_Standard
2369 and then not Is_Child_Unit (Current_Scope)
2370 and then No (Generic_Parent (Parent (L)))
2374 elsif L /= Visible_Declarations (Parent (L))
2375 or else No (Private_Declarations (Parent (L)))
2376 or else Is_Empty_List (Private_Declarations (Parent (L)))
2379 Freeze_All (First_Entity (Current_Scope), Decl);
2380 Freeze_From := Last_Entity (Current_Scope);
2382 -- At the end of the visible declarations the expressions in
2383 -- aspects of all entities declared so far must be resolved.
2384 -- The entities themselves might be frozen later, and the
2385 -- generated pragmas and attribute definition clauses analyzed
2386 -- in full at that point, but name resolution must take place
2388 -- In addition to being the proper semantics, this is mandatory
2389 -- within generic units, because global name capture requires
2390 -- those expressions to be analyzed, given that the generated
2391 -- pragmas do not appear in the original generic tree.
2393 elsif Serious_Errors_Detected = 0 then
2398 E := First_Entity (Current_Scope);
2399 while Present (E) loop
2400 Resolve_Aspect_Expressions (E);
2406 -- If next node is a body then freeze all types before the body.
2407 -- An exception occurs for some expander-generated bodies. If these
2408 -- are generated at places where in general language rules would not
2409 -- allow a freeze point, then we assume that the expander has
2410 -- explicitly checked that all required types are properly frozen,
2411 -- and we do not cause general freezing here. This special circuit
2412 -- is used when the encountered body is marked as having already
2415 -- In all other cases (bodies that come from source, and expander
2416 -- generated bodies that have not been analyzed yet), freeze all
2417 -- types now. Note that in the latter case, the expander must take
2418 -- care to attach the bodies at a proper place in the tree so as to
2419 -- not cause unwanted freezing at that point.
2421 elsif not Analyzed (Next_Decl) and then Is_Body (Next_Decl) then
2423 -- When a controlled type is frozen, the expander generates stream
2424 -- and controlled type support routines. If the freeze is caused
2425 -- by the stand alone body of Initialize, Adjust and Finalize, the
2426 -- expander will end up using the wrong version of these routines
2427 -- as the body has not been processed yet. To remedy this, detect
2428 -- a late controlled primitive and create a proper spec for it.
2429 -- This ensures that the primitive will override its inherited
2430 -- counterpart before the freeze takes place.
2432 -- If the declaration we just processed is a body, do not attempt
2433 -- to examine Next_Decl as the late primitive idiom can only apply
2434 -- to the first encountered body.
2436 -- The spec of the late primitive is not generated in ASIS mode to
2437 -- ensure a consistent list of primitives that indicates the true
2438 -- semantic structure of the program (which is not relevant when
2439 -- generating executable code.
2441 -- ??? a cleaner approach may be possible and/or this solution
2442 -- could be extended to general-purpose late primitives, TBD.
2444 if not ASIS_Mode and then not Body_Seen and then not Is_Body (Decl)
2448 if Nkind (Next_Decl) = N_Subprogram_Body then
2449 Handle_Late_Controlled_Primitive (Next_Decl);
2454 Freeze_All (Freeze_From, Decl);
2455 Freeze_From := Last_Entity (Current_Scope);
2461 -- Analyze the contracts of packages and their bodies
2464 Context := Parent (L);
2466 if Nkind (Context) = N_Package_Specification then
2468 -- When a package has private declarations, its contract must be
2469 -- analyzed at the end of the said declarations. This way both the
2470 -- analysis and freeze actions are properly synchronized in case
2471 -- of private type use within the contract.
2473 if L = Private_Declarations (Context) then
2474 Analyze_Package_Contract (Defining_Entity (Context));
2476 -- Build the bodies of the default initial condition procedures
2477 -- for all types subject to pragma Default_Initial_Condition.
2478 -- From a purely Ada stand point, this is a freezing activity,
2479 -- however freezing is not available under GNATprove_Mode. To
2480 -- accomodate both scenarios, the bodies are build at the end
2481 -- of private declaration analysis.
2483 Build_Default_Init_Cond_Procedure_Bodies (L);
2485 -- Otherwise the contract is analyzed at the end of the visible
2488 elsif L = Visible_Declarations (Context)
2489 and then No (Private_Declarations (Context))
2491 Analyze_Package_Contract (Defining_Entity (Context));
2494 elsif Nkind (Context) = N_Package_Body then
2495 Analyze_Package_Body_Contract (Defining_Entity (Context));
2498 -- Analyze the contracts of eligible constructs (see below) due to
2499 -- the delayed visibility needs of their aspects and pragmas.
2502 while Present (Decl) loop
2504 -- Entry or subprogram declarations
2506 if Nkind_In (Decl, N_Abstract_Subprogram_Declaration,
2507 N_Entry_Declaration,
2508 N_Generic_Subprogram_Declaration,
2509 N_Subprogram_Declaration)
2511 Analyze_Entry_Or_Subprogram_Contract (Defining_Entity (Decl));
2513 -- Entry or subprogram bodies
2515 elsif Nkind_In (Decl, N_Entry_Body, N_Subprogram_Body) then
2516 Analyze_Entry_Or_Subprogram_Body_Contract
2517 (Defining_Entity (Decl));
2521 elsif Nkind (Decl) = N_Object_Declaration then
2522 Analyze_Object_Contract (Defining_Entity (Decl));
2526 elsif Nkind_In (Decl, N_Protected_Type_Declaration,
2527 N_Single_Protected_Declaration)
2529 Analyze_Protected_Contract (Defining_Entity (Decl));
2531 -- Subprogram body stubs
2533 elsif Nkind (Decl) = N_Subprogram_Body_Stub then
2534 Analyze_Subprogram_Body_Stub_Contract (Defining_Entity (Decl));
2538 elsif Nkind_In (Decl, N_Single_Task_Declaration,
2539 N_Task_Type_Declaration)
2541 Analyze_Task_Contract (Defining_Entity (Decl));
2547 if Nkind (Context) = N_Package_Body then
2549 -- Ensure that all abstract states and objects declared in the
2550 -- state space of a package body are utilized as constituents.
2552 Check_Unused_Body_States (Defining_Entity (Context));
2554 -- State refinements are visible upto the end the of the package
2555 -- body declarations. Hide the state refinements from visibility
2556 -- to restore the original state conditions.
2558 Remove_Visible_Refinements (Corresponding_Spec (Context));
2561 end Analyze_Declarations;
2563 -----------------------------------
2564 -- Analyze_Full_Type_Declaration --
2565 -----------------------------------
2567 procedure Analyze_Full_Type_Declaration (N : Node_Id) is
2568 Def : constant Node_Id := Type_Definition (N);
2569 Def_Id : constant Entity_Id := Defining_Identifier (N);
2573 Is_Remote : constant Boolean :=
2574 (Is_Remote_Types (Current_Scope)
2575 or else Is_Remote_Call_Interface (Current_Scope))
2576 and then not (In_Private_Part (Current_Scope)
2577 or else In_Package_Body (Current_Scope));
2579 procedure Check_Nonoverridable_Aspects;
2580 -- Apply the rule in RM 13.1.1(18.4/4) on iterator aspects that cannot
2581 -- be overridden, and can only be confirmed on derivation.
2583 procedure Check_Ops_From_Incomplete_Type;
2584 -- If there is a tagged incomplete partial view of the type, traverse
2585 -- the primitives of the incomplete view and change the type of any
2586 -- controlling formals and result to indicate the full view. The
2587 -- primitives will be added to the full type's primitive operations
2588 -- list later in Sem_Disp.Check_Operation_From_Incomplete_Type (which
2589 -- is called from Process_Incomplete_Dependents).
2591 ----------------------------------
2592 -- Check_Nonoverridable_Aspects --
2593 ----------------------------------
2595 procedure Check_Nonoverridable_Aspects is
2596 Prev_Aspects : constant List_Id :=
2597 Aspect_Specifications (Parent (Def_Id));
2598 Par_Type : Entity_Id;
2600 function Has_Aspect_Spec
2602 Aspect_Name : Name_Id) return Boolean;
2603 -- Check whether a list of aspect specifications includes an entry
2604 -- for a specific aspect. The list is either that of a partial or
2607 ---------------------
2608 -- Has_Aspect_Spec --
2609 ---------------------
2611 function Has_Aspect_Spec
2613 Aspect_Name : Name_Id) return Boolean
2617 Spec := First (Specs);
2618 while Present (Spec) loop
2619 if Chars (Identifier (Spec)) = Aspect_Name then
2625 end Has_Aspect_Spec;
2627 -- Start of processing for Check_Nonoverridable_Aspects
2631 -- Get parent type of derived type. Note that Prev is the entity
2632 -- in the partial declaration, but its contents are now those of
2633 -- full view, while Def_Id reflects the partial view.
2635 if Is_Private_Type (Def_Id) then
2636 Par_Type := Etype (Full_View (Def_Id));
2638 Par_Type := Etype (Def_Id);
2641 -- If there is an inherited Implicit_Dereference, verify that it is
2642 -- made explicit in the partial view.
2644 if Has_Discriminants (Base_Type (Par_Type))
2645 and then Nkind (Parent (Prev)) = N_Full_Type_Declaration
2646 and then Present (Discriminant_Specifications (Parent (Prev)))
2647 and then Present (Get_Reference_Discriminant (Par_Type))
2650 not Has_Aspect_Spec (Prev_Aspects, Name_Implicit_Dereference)
2653 ("type does not inherit implicit dereference", Prev);
2656 -- If one of the views has the aspect specified, verify that it
2657 -- is consistent with that of the parent.
2660 Par_Discr : constant Entity_Id :=
2661 Get_Reference_Discriminant (Par_Type);
2662 Cur_Discr : constant Entity_Id :=
2663 Get_Reference_Discriminant (Prev);
2665 if Corresponding_Discriminant (Cur_Discr) /= Par_Discr then
2666 Error_Msg_N ("aspect incosistent with that of parent", N);
2672 -- TBD : other nonoverridable aspects.
2673 end Check_Nonoverridable_Aspects;
2675 ------------------------------------
2676 -- Check_Ops_From_Incomplete_Type --
2677 ------------------------------------
2679 procedure Check_Ops_From_Incomplete_Type is
2686 and then Ekind (Prev) = E_Incomplete_Type
2687 and then Is_Tagged_Type (Prev)
2688 and then Is_Tagged_Type (T)
2690 Elmt := First_Elmt (Primitive_Operations (Prev));
2691 while Present (Elmt) loop
2694 Formal := First_Formal (Op);
2695 while Present (Formal) loop
2696 if Etype (Formal) = Prev then
2697 Set_Etype (Formal, T);
2700 Next_Formal (Formal);
2703 if Etype (Op) = Prev then
2710 end Check_Ops_From_Incomplete_Type;
2712 -- Start of processing for Analyze_Full_Type_Declaration
2715 Prev := Find_Type_Name (N);
2717 -- The full view, if present, now points to the current type. If there
2718 -- is an incomplete partial view, set a link to it, to simplify the
2719 -- retrieval of primitive operations of the type.
2721 -- Ada 2005 (AI-50217): If the type was previously decorated when
2722 -- imported through a LIMITED WITH clause, it appears as incomplete
2723 -- but has no full view.
2725 if Ekind (Prev) = E_Incomplete_Type
2726 and then Present (Full_View (Prev))
2728 T := Full_View (Prev);
2729 Set_Incomplete_View (N, Parent (Prev));
2734 Set_Is_Pure (T, Is_Pure (Current_Scope));
2736 -- We set the flag Is_First_Subtype here. It is needed to set the
2737 -- corresponding flag for the Implicit class-wide-type created
2738 -- during tagged types processing.
2740 Set_Is_First_Subtype (T, True);
2742 -- Only composite types other than array types are allowed to have
2747 -- For derived types, the rule will be checked once we've figured
2748 -- out the parent type.
2750 when N_Derived_Type_Definition =>
2753 -- For record types, discriminants are allowed, unless we are in
2756 when N_Record_Definition =>
2757 if Present (Discriminant_Specifications (N)) then
2758 Check_SPARK_05_Restriction
2759 ("discriminant type is not allowed",
2761 (First (Discriminant_Specifications (N))));
2765 if Present (Discriminant_Specifications (N)) then
2767 ("elementary or array type cannot have discriminants",
2769 (First (Discriminant_Specifications (N))));
2773 -- Elaborate the type definition according to kind, and generate
2774 -- subsidiary (implicit) subtypes where needed. We skip this if it was
2775 -- already done (this happens during the reanalysis that follows a call
2776 -- to the high level optimizer).
2778 if not Analyzed (T) then
2782 when N_Access_To_Subprogram_Definition =>
2783 Access_Subprogram_Declaration (T, Def);
2785 -- If this is a remote access to subprogram, we must create the
2786 -- equivalent fat pointer type, and related subprograms.
2789 Process_Remote_AST_Declaration (N);
2792 -- Validate categorization rule against access type declaration
2793 -- usually a violation in Pure unit, Shared_Passive unit.
2795 Validate_Access_Type_Declaration (T, N);
2797 when N_Access_To_Object_Definition =>
2798 Access_Type_Declaration (T, Def);
2800 -- Validate categorization rule against access type declaration
2801 -- usually a violation in Pure unit, Shared_Passive unit.
2803 Validate_Access_Type_Declaration (T, N);
2805 -- If we are in a Remote_Call_Interface package and define a
2806 -- RACW, then calling stubs and specific stream attributes
2810 and then Is_Remote_Access_To_Class_Wide_Type (Def_Id)
2812 Add_RACW_Features (Def_Id);
2815 when N_Array_Type_Definition =>
2816 Array_Type_Declaration (T, Def);
2818 when N_Derived_Type_Definition =>
2819 Derived_Type_Declaration (T, N, T /= Def_Id);
2821 when N_Enumeration_Type_Definition =>
2822 Enumeration_Type_Declaration (T, Def);
2824 when N_Floating_Point_Definition =>
2825 Floating_Point_Type_Declaration (T, Def);
2827 when N_Decimal_Fixed_Point_Definition =>
2828 Decimal_Fixed_Point_Type_Declaration (T, Def);
2830 when N_Ordinary_Fixed_Point_Definition =>
2831 Ordinary_Fixed_Point_Type_Declaration (T, Def);
2833 when N_Signed_Integer_Type_Definition =>
2834 Signed_Integer_Type_Declaration (T, Def);
2836 when N_Modular_Type_Definition =>
2837 Modular_Type_Declaration (T, Def);
2839 when N_Record_Definition =>
2840 Record_Type_Declaration (T, N, Prev);
2842 -- If declaration has a parse error, nothing to elaborate.
2848 raise Program_Error;
2853 if Etype (T) = Any_Type then
2857 -- Controlled type is not allowed in SPARK
2859 if Is_Visibly_Controlled (T) then
2860 Check_SPARK_05_Restriction ("controlled type is not allowed", N);
2863 -- A type declared within a Ghost region is automatically Ghost
2864 -- (SPARK RM 6.9(2)).
2866 if Ghost_Mode > None then
2867 Set_Is_Ghost_Entity (T);
2870 -- Some common processing for all types
2872 Set_Depends_On_Private (T, Has_Private_Component (T));
2873 Check_Ops_From_Incomplete_Type;
2875 -- Both the declared entity, and its anonymous base type if one was
2876 -- created, need freeze nodes allocated.
2879 B : constant Entity_Id := Base_Type (T);
2882 -- In the case where the base type differs from the first subtype, we
2883 -- pre-allocate a freeze node, and set the proper link to the first
2884 -- subtype. Freeze_Entity will use this preallocated freeze node when
2885 -- it freezes the entity.
2887 -- This does not apply if the base type is a generic type, whose
2888 -- declaration is independent of the current derived definition.
2890 if B /= T and then not Is_Generic_Type (B) then
2891 Ensure_Freeze_Node (B);
2892 Set_First_Subtype_Link (Freeze_Node (B), T);
2895 -- A type that is imported through a limited_with clause cannot
2896 -- generate any code, and thus need not be frozen. However, an access
2897 -- type with an imported designated type needs a finalization list,
2898 -- which may be referenced in some other package that has non-limited
2899 -- visibility on the designated type. Thus we must create the
2900 -- finalization list at the point the access type is frozen, to
2901 -- prevent unsatisfied references at link time.
2903 if not From_Limited_With (T) or else Is_Access_Type (T) then
2904 Set_Has_Delayed_Freeze (T);
2908 -- Case where T is the full declaration of some private type which has
2909 -- been swapped in Defining_Identifier (N).
2911 if T /= Def_Id and then Is_Private_Type (Def_Id) then
2912 Process_Full_View (N, T, Def_Id);
2914 -- Record the reference. The form of this is a little strange, since
2915 -- the full declaration has been swapped in. So the first parameter
2916 -- here represents the entity to which a reference is made which is
2917 -- the "real" entity, i.e. the one swapped in, and the second
2918 -- parameter provides the reference location.
2920 -- Also, we want to kill Has_Pragma_Unreferenced temporarily here
2921 -- since we don't want a complaint about the full type being an
2922 -- unwanted reference to the private type
2925 B : constant Boolean := Has_Pragma_Unreferenced (T);
2927 Set_Has_Pragma_Unreferenced (T, False);
2928 Generate_Reference (T, T, 'c');
2929 Set_Has_Pragma_Unreferenced (T, B);
2932 Set_Completion_Referenced (Def_Id);
2934 -- For completion of incomplete type, process incomplete dependents
2935 -- and always mark the full type as referenced (it is the incomplete
2936 -- type that we get for any real reference).
2938 elsif Ekind (Prev) = E_Incomplete_Type then
2939 Process_Incomplete_Dependents (N, T, Prev);
2940 Generate_Reference (Prev, Def_Id, 'c');
2941 Set_Completion_Referenced (Def_Id);
2943 -- If not private type or incomplete type completion, this is a real
2944 -- definition of a new entity, so record it.
2947 Generate_Definition (Def_Id);
2950 -- Propagate any pending access types whose finalization masters need to
2951 -- be fully initialized from the partial to the full view. Guard against
2952 -- an illegal full view that remains unanalyzed.
2954 if Is_Type (Def_Id) and then Is_Incomplete_Or_Private_Type (Prev) then
2955 Set_Pending_Access_Types (Def_Id, Pending_Access_Types (Prev));
2958 if Chars (Scope (Def_Id)) = Name_System
2959 and then Chars (Def_Id) = Name_Address
2960 and then Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (N)))
2962 Set_Is_Descendent_Of_Address (Def_Id);
2963 Set_Is_Descendent_Of_Address (Base_Type (Def_Id));
2964 Set_Is_Descendent_Of_Address (Prev);
2967 Set_Optimize_Alignment_Flags (Def_Id);
2968 Check_Eliminated (Def_Id);
2970 -- If the declaration is a completion and aspects are present, apply
2971 -- them to the entity for the type which is currently the partial
2972 -- view, but which is the one that will be frozen.
2974 if Has_Aspects (N) then
2976 -- In most cases the partial view is a private type, and both views
2977 -- appear in different declarative parts. In the unusual case where
2978 -- the partial view is incomplete, perform the analysis on the
2979 -- full view, to prevent freezing anomalies with the corresponding
2980 -- class-wide type, which otherwise might be frozen before the
2981 -- dispatch table is built.
2984 and then Ekind (Prev) /= E_Incomplete_Type
2986 Analyze_Aspect_Specifications (N, Prev);
2991 Analyze_Aspect_Specifications (N, Def_Id);
2995 if Is_Derived_Type (Prev)
2996 and then Def_Id /= Prev
2998 Check_Nonoverridable_Aspects;
3000 end Analyze_Full_Type_Declaration;
3002 ----------------------------------
3003 -- Analyze_Incomplete_Type_Decl --
3004 ----------------------------------
3006 procedure Analyze_Incomplete_Type_Decl (N : Node_Id) is
3007 F : constant Boolean := Is_Pure (Current_Scope);
3011 Check_SPARK_05_Restriction ("incomplete type is not allowed", N);
3013 Generate_Definition (Defining_Identifier (N));
3015 -- Process an incomplete declaration. The identifier must not have been
3016 -- declared already in the scope. However, an incomplete declaration may
3017 -- appear in the private part of a package, for a private type that has
3018 -- already been declared.
3020 -- In this case, the discriminants (if any) must match
3022 T := Find_Type_Name (N);
3024 Set_Ekind (T, E_Incomplete_Type);
3025 Init_Size_Align (T);
3026 Set_Is_First_Subtype (T, True);
3029 -- An incomplete type declared within a Ghost region is automatically
3030 -- Ghost (SPARK RM 6.9(2)).
3032 if Ghost_Mode > None then
3033 Set_Is_Ghost_Entity (T);
3036 -- Ada 2005 (AI-326): Minimum decoration to give support to tagged
3037 -- incomplete types.
3039 if Tagged_Present (N) then
3040 Set_Is_Tagged_Type (T, True);
3041 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
3042 Make_Class_Wide_Type (T);
3043 Set_Direct_Primitive_Operations (T, New_Elmt_List);
3048 Set_Stored_Constraint (T, No_Elist);
3050 if Present (Discriminant_Specifications (N)) then
3051 Process_Discriminants (N);
3056 -- If the type has discriminants, non-trivial subtypes may be
3057 -- declared before the full view of the type. The full views of those
3058 -- subtypes will be built after the full view of the type.
3060 Set_Private_Dependents (T, New_Elmt_List);
3062 end Analyze_Incomplete_Type_Decl;
3064 -----------------------------------
3065 -- Analyze_Interface_Declaration --
3066 -----------------------------------
3068 procedure Analyze_Interface_Declaration (T : Entity_Id; Def : Node_Id) is
3069 CW : constant Entity_Id := Class_Wide_Type (T);
3072 Set_Is_Tagged_Type (T);
3073 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
3075 Set_Is_Limited_Record (T, Limited_Present (Def)
3076 or else Task_Present (Def)
3077 or else Protected_Present (Def)
3078 or else Synchronized_Present (Def));
3080 -- Type is abstract if full declaration carries keyword, or if previous
3081 -- partial view did.
3083 Set_Is_Abstract_Type (T);
3084 Set_Is_Interface (T);
3086 -- Type is a limited interface if it includes the keyword limited, task,
3087 -- protected, or synchronized.
3089 Set_Is_Limited_Interface
3090 (T, Limited_Present (Def)
3091 or else Protected_Present (Def)
3092 or else Synchronized_Present (Def)
3093 or else Task_Present (Def));
3095 Set_Interfaces (T, New_Elmt_List);
3096 Set_Direct_Primitive_Operations (T, New_Elmt_List);
3098 -- Complete the decoration of the class-wide entity if it was already
3099 -- built (i.e. during the creation of the limited view)
3101 if Present (CW) then
3102 Set_Is_Interface (CW);
3103 Set_Is_Limited_Interface (CW, Is_Limited_Interface (T));
3106 -- Check runtime support for synchronized interfaces
3108 if (Is_Task_Interface (T)
3109 or else Is_Protected_Interface (T)
3110 or else Is_Synchronized_Interface (T))
3111 and then not RTE_Available (RE_Select_Specific_Data)
3113 Error_Msg_CRT ("synchronized interfaces", T);
3115 end Analyze_Interface_Declaration;
3117 -----------------------------
3118 -- Analyze_Itype_Reference --
3119 -----------------------------
3121 -- Nothing to do. This node is placed in the tree only for the benefit of
3122 -- back end processing, and has no effect on the semantic processing.
3124 procedure Analyze_Itype_Reference (N : Node_Id) is
3126 pragma Assert (Is_Itype (Itype (N)));
3128 end Analyze_Itype_Reference;
3130 --------------------------------
3131 -- Analyze_Number_Declaration --
3132 --------------------------------
3134 procedure Analyze_Number_Declaration (N : Node_Id) is
3135 E : constant Node_Id := Expression (N);
3136 Id : constant Entity_Id := Defining_Identifier (N);
3137 Index : Interp_Index;
3142 Generate_Definition (Id);
3145 -- A number declared within a Ghost region is automatically Ghost
3146 -- (SPARK RM 6.9(2)).
3148 if Ghost_Mode > None then
3149 Set_Is_Ghost_Entity (Id);
3152 -- This is an optimization of a common case of an integer literal
3154 if Nkind (E) = N_Integer_Literal then
3155 Set_Is_Static_Expression (E, True);
3156 Set_Etype (E, Universal_Integer);
3158 Set_Etype (Id, Universal_Integer);
3159 Set_Ekind (Id, E_Named_Integer);
3160 Set_Is_Frozen (Id, True);
3164 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3166 -- Process expression, replacing error by integer zero, to avoid
3167 -- cascaded errors or aborts further along in the processing
3169 -- Replace Error by integer zero, which seems least likely to cause
3173 Rewrite (E, Make_Integer_Literal (Sloc (E), Uint_0));
3174 Set_Error_Posted (E);
3179 -- Verify that the expression is static and numeric. If
3180 -- the expression is overloaded, we apply the preference
3181 -- rule that favors root numeric types.
3183 if not Is_Overloaded (E) then
3185 if Has_Dynamic_Predicate_Aspect (T) then
3187 ("subtype has dynamic predicate, "
3188 & "not allowed in number declaration", N);
3194 Get_First_Interp (E, Index, It);
3195 while Present (It.Typ) loop
3196 if (Is_Integer_Type (It.Typ) or else Is_Real_Type (It.Typ))
3197 and then (Scope (Base_Type (It.Typ))) = Standard_Standard
3199 if T = Any_Type then
3202 elsif It.Typ = Universal_Real
3204 It.Typ = Universal_Integer
3206 -- Choose universal interpretation over any other
3213 Get_Next_Interp (Index, It);
3217 if Is_Integer_Type (T) then
3219 Set_Etype (Id, Universal_Integer);
3220 Set_Ekind (Id, E_Named_Integer);
3222 elsif Is_Real_Type (T) then
3224 -- Because the real value is converted to universal_real, this is a
3225 -- legal context for a universal fixed expression.
3227 if T = Universal_Fixed then
3229 Loc : constant Source_Ptr := Sloc (N);
3230 Conv : constant Node_Id := Make_Type_Conversion (Loc,
3232 New_Occurrence_Of (Universal_Real, Loc),
3233 Expression => Relocate_Node (E));
3240 elsif T = Any_Fixed then
3241 Error_Msg_N ("illegal context for mixed mode operation", E);
3243 -- Expression is of the form : universal_fixed * integer. Try to
3244 -- resolve as universal_real.
3246 T := Universal_Real;
3251 Set_Etype (Id, Universal_Real);
3252 Set_Ekind (Id, E_Named_Real);
3255 Wrong_Type (E, Any_Numeric);
3259 Set_Ekind (Id, E_Constant);
3260 Set_Never_Set_In_Source (Id, True);
3261 Set_Is_True_Constant (Id, True);
3265 if Nkind_In (E, N_Integer_Literal, N_Real_Literal) then
3266 Set_Etype (E, Etype (Id));
3269 if not Is_OK_Static_Expression (E) then
3270 Flag_Non_Static_Expr
3271 ("non-static expression used in number declaration!", E);
3272 Rewrite (E, Make_Integer_Literal (Sloc (N), 1));
3273 Set_Etype (E, Any_Type);
3275 end Analyze_Number_Declaration;
3277 --------------------------------
3278 -- Analyze_Object_Declaration --
3279 --------------------------------
3281 procedure Analyze_Object_Declaration (N : Node_Id) is
3282 Loc : constant Source_Ptr := Sloc (N);
3283 Id : constant Entity_Id := Defining_Identifier (N);
3287 E : Node_Id := Expression (N);
3288 -- E is set to Expression (N) throughout this routine. When
3289 -- Expression (N) is modified, E is changed accordingly.
3291 Prev_Entity : Entity_Id := Empty;
3293 function Count_Tasks (T : Entity_Id) return Uint;
3294 -- This function is called when a non-generic library level object of a
3295 -- task type is declared. Its function is to count the static number of
3296 -- tasks declared within the type (it is only called if Has_Task is set
3297 -- for T). As a side effect, if an array of tasks with non-static bounds
3298 -- or a variant record type is encountered, Check_Restriction is called
3299 -- indicating the count is unknown.
3301 function Delayed_Aspect_Present return Boolean;
3302 -- If the declaration has an expression that is an aggregate, and it
3303 -- has aspects that require delayed analysis, the resolution of the
3304 -- aggregate must be deferred to the freeze point of the objet. This
3305 -- special processing was created for address clauses, but it must
3306 -- also apply to Alignment. This must be done before the aspect
3307 -- specifications are analyzed because we must handle the aggregate
3308 -- before the analysis of the object declaration is complete.
3310 -- Any other relevant delayed aspects on object declarations ???
3316 function Count_Tasks (T : Entity_Id) return Uint is
3322 if Is_Task_Type (T) then
3325 elsif Is_Record_Type (T) then
3326 if Has_Discriminants (T) then
3327 Check_Restriction (Max_Tasks, N);
3332 C := First_Component (T);
3333 while Present (C) loop
3334 V := V + Count_Tasks (Etype (C));
3341 elsif Is_Array_Type (T) then
3342 X := First_Index (T);
3343 V := Count_Tasks (Component_Type (T));
3344 while Present (X) loop
3347 if not Is_OK_Static_Subtype (C) then
3348 Check_Restriction (Max_Tasks, N);
3351 V := V * (UI_Max (Uint_0,
3352 Expr_Value (Type_High_Bound (C)) -
3353 Expr_Value (Type_Low_Bound (C)) + Uint_1));
3366 ----------------------------
3367 -- Delayed_Aspect_Present --
3368 ----------------------------
3370 function Delayed_Aspect_Present return Boolean is
3375 if Present (Aspect_Specifications (N)) then
3376 A := First (Aspect_Specifications (N));
3377 A_Id := Get_Aspect_Id (Chars (Identifier (A)));
3378 while Present (A) loop
3379 if A_Id = Aspect_Alignment or else A_Id = Aspect_Address then
3388 end Delayed_Aspect_Present;
3392 Save_Ghost_Mode : constant Ghost_Mode_Type := Ghost_Mode;
3394 -- Start of processing for Analyze_Object_Declaration
3397 -- There are three kinds of implicit types generated by an
3398 -- object declaration:
3400 -- 1. Those generated by the original Object Definition
3402 -- 2. Those generated by the Expression
3404 -- 3. Those used to constrain the Object Definition with the
3405 -- expression constraints when the definition is unconstrained.
3407 -- They must be generated in this order to avoid order of elaboration
3408 -- issues. Thus the first step (after entering the name) is to analyze
3409 -- the object definition.
3411 if Constant_Present (N) then
3412 Prev_Entity := Current_Entity_In_Scope (Id);
3414 if Present (Prev_Entity)
3416 -- If the homograph is an implicit subprogram, it is overridden
3417 -- by the current declaration.
3419 ((Is_Overloadable (Prev_Entity)
3420 and then Is_Inherited_Operation (Prev_Entity))
3422 -- The current object is a discriminal generated for an entry
3423 -- family index. Even though the index is a constant, in this
3424 -- particular context there is no true constant redeclaration.
3425 -- Enter_Name will handle the visibility.
3428 (Is_Discriminal (Id)
3429 and then Ekind (Discriminal_Link (Id)) =
3430 E_Entry_Index_Parameter)
3432 -- The current object is the renaming for a generic declared
3433 -- within the instance.
3436 (Ekind (Prev_Entity) = E_Package
3437 and then Nkind (Parent (Prev_Entity)) =
3438 N_Package_Renaming_Declaration
3439 and then not Comes_From_Source (Prev_Entity)
3441 Is_Generic_Instance (Renamed_Entity (Prev_Entity))))
3443 Prev_Entity := Empty;
3447 -- The object declaration is Ghost when it is subject to pragma Ghost or
3448 -- completes a deferred Ghost constant. Set the mode now to ensure that
3449 -- any nodes generated during analysis and expansion are properly marked
3452 Set_Ghost_Mode (N, Prev_Entity);
3454 if Present (Prev_Entity) then
3455 Constant_Redeclaration (Id, N, T);
3457 Generate_Reference (Prev_Entity, Id, 'c');
3458 Set_Completion_Referenced (Id);
3460 if Error_Posted (N) then
3462 -- Type mismatch or illegal redeclaration, Do not analyze
3463 -- expression to avoid cascaded errors.
3465 T := Find_Type_Of_Object (Object_Definition (N), N);
3467 Set_Ekind (Id, E_Variable);
3471 -- In the normal case, enter identifier at the start to catch premature
3472 -- usage in the initialization expression.
3475 Generate_Definition (Id);
3478 Mark_Coextensions (N, Object_Definition (N));
3480 T := Find_Type_Of_Object (Object_Definition (N), N);
3482 if Nkind (Object_Definition (N)) = N_Access_Definition
3484 (Access_To_Subprogram_Definition (Object_Definition (N)))
3485 and then Protected_Present
3486 (Access_To_Subprogram_Definition (Object_Definition (N)))
3488 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
3491 if Error_Posted (Id) then
3493 Set_Ekind (Id, E_Variable);
3498 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
3499 -- out some static checks
3501 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
3503 -- In case of aggregates we must also take care of the correct
3504 -- initialization of nested aggregates bug this is done at the
3505 -- point of the analysis of the aggregate (see sem_aggr.adb).
3507 if Present (Expression (N))
3508 and then Nkind (Expression (N)) = N_Aggregate
3514 Save_Typ : constant Entity_Id := Etype (Id);
3516 Set_Etype (Id, T); -- Temp. decoration for static checks
3517 Null_Exclusion_Static_Checks (N);
3518 Set_Etype (Id, Save_Typ);
3523 -- Object is marked pure if it is in a pure scope
3525 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3527 -- If deferred constant, make sure context is appropriate. We detect
3528 -- a deferred constant as a constant declaration with no expression.
3529 -- A deferred constant can appear in a package body if its completion
3530 -- is by means of an interface pragma.
3532 if Constant_Present (N) and then No (E) then
3534 -- A deferred constant may appear in the declarative part of the
3535 -- following constructs:
3539 -- extended return statements
3542 -- subprogram bodies
3545 -- When declared inside a package spec, a deferred constant must be
3546 -- completed by a full constant declaration or pragma Import. In all
3547 -- other cases, the only proper completion is pragma Import. Extended
3548 -- return statements are flagged as invalid contexts because they do
3549 -- not have a declarative part and so cannot accommodate the pragma.
3551 if Ekind (Current_Scope) = E_Return_Statement then
3553 ("invalid context for deferred constant declaration (RM 7.4)",
3556 ("\declaration requires an initialization expression",
3558 Set_Constant_Present (N, False);
3560 -- In Ada 83, deferred constant must be of private type
3562 elsif not Is_Private_Type (T) then
3563 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
3565 ("(Ada 83) deferred constant must be private type", N);
3569 -- If not a deferred constant, then the object declaration freezes
3570 -- its type, unless the object is of an anonymous type and has delayed
3571 -- aspects. In that case the type is frozen when the object itself is.
3574 Check_Fully_Declared (T, N);
3576 if Has_Delayed_Aspects (Id)
3577 and then Is_Array_Type (T)
3578 and then Is_Itype (T)
3580 Set_Has_Delayed_Freeze (T);
3582 Freeze_Before (N, T);
3586 -- If the object was created by a constrained array definition, then
3587 -- set the link in both the anonymous base type and anonymous subtype
3588 -- that are built to represent the array type to point to the object.
3590 if Nkind (Object_Definition (Declaration_Node (Id))) =
3591 N_Constrained_Array_Definition
3593 Set_Related_Array_Object (T, Id);
3594 Set_Related_Array_Object (Base_Type (T), Id);
3597 -- Special checks for protected objects not at library level
3599 if Is_Protected_Type (T)
3600 and then not Is_Library_Level_Entity (Id)
3602 Check_Restriction (No_Local_Protected_Objects, Id);
3604 -- Protected objects with interrupt handlers must be at library level
3606 -- Ada 2005: This test is not needed (and the corresponding clause
3607 -- in the RM is removed) because accessibility checks are sufficient
3608 -- to make handlers not at the library level illegal.
3610 -- AI05-0303: The AI is in fact a binding interpretation, and thus
3611 -- applies to the '95 version of the language as well.
3613 if Has_Interrupt_Handler (T) and then Ada_Version < Ada_95 then
3615 ("interrupt object can only be declared at library level", Id);
3619 -- The actual subtype of the object is the nominal subtype, unless
3620 -- the nominal one is unconstrained and obtained from the expression.
3624 -- These checks should be performed before the initialization expression
3625 -- is considered, so that the Object_Definition node is still the same
3626 -- as in source code.
3628 -- In SPARK, the nominal subtype is always given by a subtype mark
3629 -- and must not be unconstrained. (The only exception to this is the
3630 -- acceptance of declarations of constants of type String.)
3632 if not Nkind_In (Object_Definition (N), N_Expanded_Name, N_Identifier)
3634 Check_SPARK_05_Restriction
3635 ("subtype mark required", Object_Definition (N));
3637 elsif Is_Array_Type (T)
3638 and then not Is_Constrained (T)
3639 and then T /= Standard_String
3641 Check_SPARK_05_Restriction
3642 ("subtype mark of constrained type expected",
3643 Object_Definition (N));
3646 -- There are no aliased objects in SPARK
3648 if Aliased_Present (N) then
3649 Check_SPARK_05_Restriction ("aliased object is not allowed", N);
3652 -- Process initialization expression if present and not in error
3654 if Present (E) and then E /= Error then
3656 -- Generate an error in case of CPP class-wide object initialization.
3657 -- Required because otherwise the expansion of the class-wide
3658 -- assignment would try to use 'size to initialize the object
3659 -- (primitive that is not available in CPP tagged types).
3661 if Is_Class_Wide_Type (Act_T)
3663 (Is_CPP_Class (Root_Type (Etype (Act_T)))
3665 (Present (Full_View (Root_Type (Etype (Act_T))))
3667 Is_CPP_Class (Full_View (Root_Type (Etype (Act_T))))))
3670 ("predefined assignment not available for 'C'P'P tagged types",
3674 Mark_Coextensions (N, E);
3677 -- In case of errors detected in the analysis of the expression,
3678 -- decorate it with the expected type to avoid cascaded errors
3680 if No (Etype (E)) then
3684 -- If an initialization expression is present, then we set the
3685 -- Is_True_Constant flag. It will be reset if this is a variable
3686 -- and it is indeed modified.
3688 Set_Is_True_Constant (Id, True);
3690 -- If we are analyzing a constant declaration, set its completion
3691 -- flag after analyzing and resolving the expression.
3693 if Constant_Present (N) then
3694 Set_Has_Completion (Id);
3697 -- Set type and resolve (type may be overridden later on). Note:
3698 -- Ekind (Id) must still be E_Void at this point so that incorrect
3699 -- early usage within E is properly diagnosed.
3703 -- If the expression is an aggregate we must look ahead to detect
3704 -- the possible presence of an address clause, and defer resolution
3705 -- and expansion of the aggregate to the freeze point of the entity.
3707 -- This is not always legal because the aggregate may contain other
3708 -- references that need freezing, e.g. references to other entities
3709 -- with address clauses. In any case, when compiling with -gnatI the
3710 -- presence of the address clause must be ignored.
3712 if Comes_From_Source (N)
3713 and then Expander_Active
3714 and then Nkind (E) = N_Aggregate
3716 ((Present (Following_Address_Clause (N))
3717 and then not Ignore_Rep_Clauses)
3718 or else Delayed_Aspect_Present)
3726 -- No further action needed if E is a call to an inlined function
3727 -- which returns an unconstrained type and it has been expanded into
3728 -- a procedure call. In that case N has been replaced by an object
3729 -- declaration without initializing expression and it has been
3730 -- analyzed (see Expand_Inlined_Call).
3732 if Back_End_Inlining
3733 and then Expander_Active
3734 and then Nkind (E) = N_Function_Call
3735 and then Nkind (Name (E)) in N_Has_Entity
3736 and then Is_Inlined (Entity (Name (E)))
3737 and then not Is_Constrained (Etype (E))
3738 and then Analyzed (N)
3739 and then No (Expression (N))
3741 Ghost_Mode := Save_Ghost_Mode;
3745 -- If E is null and has been replaced by an N_Raise_Constraint_Error
3746 -- node (which was marked already-analyzed), we need to set the type
3747 -- to something other than Any_Access in order to keep gigi happy.
3749 if Etype (E) = Any_Access then
3753 -- If the object is an access to variable, the initialization
3754 -- expression cannot be an access to constant.
3756 if Is_Access_Type (T)
3757 and then not Is_Access_Constant (T)
3758 and then Is_Access_Type (Etype (E))
3759 and then Is_Access_Constant (Etype (E))
3762 ("access to variable cannot be initialized with an "
3763 & "access-to-constant expression", E);
3766 if not Assignment_OK (N) then
3767 Check_Initialization (T, E);
3770 Check_Unset_Reference (E);
3772 -- If this is a variable, then set current value. If this is a
3773 -- declared constant of a scalar type with a static expression,
3774 -- indicate that it is always valid.
3776 if not Constant_Present (N) then
3777 if Compile_Time_Known_Value (E) then
3778 Set_Current_Value (Id, E);
3781 elsif Is_Scalar_Type (T) and then Is_OK_Static_Expression (E) then
3782 Set_Is_Known_Valid (Id);
3785 -- Deal with setting of null flags
3787 if Is_Access_Type (T) then
3788 if Known_Non_Null (E) then
3789 Set_Is_Known_Non_Null (Id, True);
3790 elsif Known_Null (E) and then not Can_Never_Be_Null (Id) then
3791 Set_Is_Known_Null (Id, True);
3795 -- Check incorrect use of dynamically tagged expressions
3797 if Is_Tagged_Type (T) then
3798 Check_Dynamically_Tagged_Expression
3804 Apply_Scalar_Range_Check (E, T);
3805 Apply_Static_Length_Check (E, T);
3807 if Nkind (Original_Node (N)) = N_Object_Declaration
3808 and then Comes_From_Source (Original_Node (N))
3810 -- Only call test if needed
3812 and then Restriction_Check_Required (SPARK_05)
3813 and then not Is_SPARK_05_Initialization_Expr (Original_Node (E))
3815 Check_SPARK_05_Restriction
3816 ("initialization expression is not appropriate", E);
3819 -- A formal parameter of a specific tagged type whose related
3820 -- subprogram is subject to pragma Extensions_Visible with value
3821 -- "False" cannot be implicitly converted to a class-wide type by
3822 -- means of an initialization expression (SPARK RM 6.1.7(3)).
3824 if Is_Class_Wide_Type (T) and then Is_EVF_Expression (E) then
3826 ("formal parameter with Extensions_Visible False cannot be "
3827 & "implicitly converted to class-wide type", E);
3831 -- If the No_Streams restriction is set, check that the type of the
3832 -- object is not, and does not contain, any subtype derived from
3833 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
3834 -- Has_Stream just for efficiency reasons. There is no point in
3835 -- spending time on a Has_Stream check if the restriction is not set.
3837 if Restriction_Check_Required (No_Streams) then
3838 if Has_Stream (T) then
3839 Check_Restriction (No_Streams, N);
3843 -- Deal with predicate check before we start to do major rewriting. It
3844 -- is OK to initialize and then check the initialized value, since the
3845 -- object goes out of scope if we get a predicate failure. Note that we
3846 -- do this in the analyzer and not the expander because the analyzer
3847 -- does some substantial rewriting in some cases.
3849 -- We need a predicate check if the type has predicates, and if either
3850 -- there is an initializing expression, or for default initialization
3851 -- when we have at least one case of an explicit default initial value
3852 -- and then this is not an internal declaration whose initialization
3853 -- comes later (as for an aggregate expansion).
3855 if not Suppress_Assignment_Checks (N)
3856 and then Present (Predicate_Function (T))
3857 and then not No_Initialization (N)
3861 Is_Partially_Initialized_Type (T, Include_Implicit => False))
3863 -- If the type has a static predicate and the expression is known at
3864 -- compile time, see if the expression satisfies the predicate.
3867 Check_Expression_Against_Static_Predicate (E, T);
3871 Make_Predicate_Check (T, New_Occurrence_Of (Id, Loc)));
3874 -- Case of unconstrained type
3876 if not Is_Definite_Subtype (T) then
3878 -- In SPARK, a declaration of unconstrained type is allowed
3879 -- only for constants of type string.
3881 if Is_String_Type (T) and then not Constant_Present (N) then
3882 Check_SPARK_05_Restriction
3883 ("declaration of object of unconstrained type not allowed", N);
3886 -- Nothing to do in deferred constant case
3888 if Constant_Present (N) and then No (E) then
3891 -- Case of no initialization present
3894 if No_Initialization (N) then
3897 elsif Is_Class_Wide_Type (T) then
3899 ("initialization required in class-wide declaration ", N);
3903 ("unconstrained subtype not allowed (need initialization)",
3904 Object_Definition (N));
3906 if Is_Record_Type (T) and then Has_Discriminants (T) then
3908 ("\provide initial value or explicit discriminant values",
3909 Object_Definition (N));
3912 ("\or give default discriminant values for type&",
3913 Object_Definition (N), T);
3915 elsif Is_Array_Type (T) then
3917 ("\provide initial value or explicit array bounds",
3918 Object_Definition (N));
3922 -- Case of initialization present but in error. Set initial
3923 -- expression as absent (but do not make above complaints)
3925 elsif E = Error then
3926 Set_Expression (N, Empty);
3929 -- Case of initialization present
3932 -- Check restrictions in Ada 83
3934 if not Constant_Present (N) then
3936 -- Unconstrained variables not allowed in Ada 83 mode
3938 if Ada_Version = Ada_83
3939 and then Comes_From_Source (Object_Definition (N))
3942 ("(Ada 83) unconstrained variable not allowed",
3943 Object_Definition (N));
3947 -- Now we constrain the variable from the initializing expression
3949 -- If the expression is an aggregate, it has been expanded into
3950 -- individual assignments. Retrieve the actual type from the
3951 -- expanded construct.
3953 if Is_Array_Type (T)
3954 and then No_Initialization (N)
3955 and then Nkind (Original_Node (E)) = N_Aggregate
3959 -- In case of class-wide interface object declarations we delay
3960 -- the generation of the equivalent record type declarations until
3961 -- its expansion because there are cases in they are not required.
3963 elsif Is_Interface (T) then
3966 -- In GNATprove mode, Expand_Subtype_From_Expr does nothing. Thus,
3967 -- we should prevent the generation of another Itype with the
3968 -- same name as the one already generated, or we end up with
3969 -- two identical types in GNATprove.
3971 elsif GNATprove_Mode then
3974 -- If the type is an unchecked union, no subtype can be built from
3975 -- the expression. Rewrite declaration as a renaming, which the
3976 -- back-end can handle properly. This is a rather unusual case,
3977 -- because most unchecked_union declarations have default values
3978 -- for discriminants and are thus not indefinite.
3980 elsif Is_Unchecked_Union (T) then
3981 if Constant_Present (N) or else Nkind (E) = N_Function_Call then
3982 Set_Ekind (Id, E_Constant);
3984 Set_Ekind (Id, E_Variable);
3987 -- An object declared within a Ghost region is automatically
3988 -- Ghost (SPARK RM 6.9(2)).
3990 if Ghost_Mode > None then
3991 Set_Is_Ghost_Entity (Id);
3993 -- The Ghost policy in effect at the point of declaration
3994 -- and at the point of completion must match
3995 -- (SPARK RM 6.9(14)).
3997 if Present (Prev_Entity)
3998 and then Is_Ghost_Entity (Prev_Entity)
4000 Check_Ghost_Completion (Prev_Entity, Id);
4005 Make_Object_Renaming_Declaration (Loc,
4006 Defining_Identifier => Id,
4007 Subtype_Mark => New_Occurrence_Of (T, Loc),
4010 Set_Renamed_Object (Id, E);
4011 Freeze_Before (N, T);
4014 Ghost_Mode := Save_Ghost_Mode;
4018 Expand_Subtype_From_Expr (N, T, Object_Definition (N), E);
4019 Act_T := Find_Type_Of_Object (Object_Definition (N), N);
4022 Set_Is_Constr_Subt_For_U_Nominal (Act_T);
4024 if Aliased_Present (N) then
4025 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
4028 Freeze_Before (N, Act_T);
4029 Freeze_Before (N, T);
4032 elsif Is_Array_Type (T)
4033 and then No_Initialization (N)
4034 and then Nkind (Original_Node (E)) = N_Aggregate
4036 if not Is_Entity_Name (Object_Definition (N)) then
4038 Check_Compile_Time_Size (Act_T);
4040 if Aliased_Present (N) then
4041 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
4045 -- When the given object definition and the aggregate are specified
4046 -- independently, and their lengths might differ do a length check.
4047 -- This cannot happen if the aggregate is of the form (others =>...)
4049 if not Is_Constrained (T) then
4052 elsif Nkind (E) = N_Raise_Constraint_Error then
4054 -- Aggregate is statically illegal. Place back in declaration
4056 Set_Expression (N, E);
4057 Set_No_Initialization (N, False);
4059 elsif T = Etype (E) then
4062 elsif Nkind (E) = N_Aggregate
4063 and then Present (Component_Associations (E))
4064 and then Present (Choices (First (Component_Associations (E))))
4065 and then Nkind (First
4066 (Choices (First (Component_Associations (E))))) = N_Others_Choice
4071 Apply_Length_Check (E, T);
4074 -- If the type is limited unconstrained with defaulted discriminants and
4075 -- there is no expression, then the object is constrained by the
4076 -- defaults, so it is worthwhile building the corresponding subtype.
4078 elsif (Is_Limited_Record (T) or else Is_Concurrent_Type (T))
4079 and then not Is_Constrained (T)
4080 and then Has_Discriminants (T)
4083 Act_T := Build_Default_Subtype (T, N);
4085 -- Ada 2005: A limited object may be initialized by means of an
4086 -- aggregate. If the type has default discriminants it has an
4087 -- unconstrained nominal type, Its actual subtype will be obtained
4088 -- from the aggregate, and not from the default discriminants.
4093 Rewrite (Object_Definition (N), New_Occurrence_Of (Act_T, Loc));
4095 elsif Nkind (E) = N_Function_Call
4096 and then Constant_Present (N)
4097 and then Has_Unconstrained_Elements (Etype (E))
4099 -- The back-end has problems with constants of a discriminated type
4100 -- with defaults, if the initial value is a function call. We
4101 -- generate an intermediate temporary that will receive a reference
4102 -- to the result of the call. The initialization expression then
4103 -- becomes a dereference of that temporary.
4105 Remove_Side_Effects (E);
4107 -- If this is a constant declaration of an unconstrained type and
4108 -- the initialization is an aggregate, we can use the subtype of the
4109 -- aggregate for the declared entity because it is immutable.
4111 elsif not Is_Constrained (T)
4112 and then Has_Discriminants (T)
4113 and then Constant_Present (N)
4114 and then not Has_Unchecked_Union (T)
4115 and then Nkind (E) = N_Aggregate
4120 -- Check No_Wide_Characters restriction
4122 Check_Wide_Character_Restriction (T, Object_Definition (N));
4124 -- Indicate this is not set in source. Certainly true for constants, and
4125 -- true for variables so far (will be reset for a variable if and when
4126 -- we encounter a modification in the source).
4128 Set_Never_Set_In_Source (Id);
4130 -- Now establish the proper kind and type of the object
4132 if Constant_Present (N) then
4133 Set_Ekind (Id, E_Constant);
4134 Set_Is_True_Constant (Id);
4137 Set_Ekind (Id, E_Variable);
4139 -- A variable is set as shared passive if it appears in a shared
4140 -- passive package, and is at the outer level. This is not done for
4141 -- entities generated during expansion, because those are always
4142 -- manipulated locally.
4144 if Is_Shared_Passive (Current_Scope)
4145 and then Is_Library_Level_Entity (Id)
4146 and then Comes_From_Source (Id)
4148 Set_Is_Shared_Passive (Id);
4149 Check_Shared_Var (Id, T, N);
4152 -- Set Has_Initial_Value if initializing expression present. Note
4153 -- that if there is no initializing expression, we leave the state
4154 -- of this flag unchanged (usually it will be False, but notably in
4155 -- the case of exception choice variables, it will already be true).
4158 Set_Has_Initial_Value (Id);
4162 -- Initialize alignment and size and capture alignment setting
4164 Init_Alignment (Id);
4166 Set_Optimize_Alignment_Flags (Id);
4168 -- An object declared within a Ghost region is automatically Ghost
4169 -- (SPARK RM 6.9(2)).
4171 if Ghost_Mode > None
4172 or else (Present (Prev_Entity) and then Is_Ghost_Entity (Prev_Entity))
4174 Set_Is_Ghost_Entity (Id);
4176 -- The Ghost policy in effect at the point of declaration and at the
4177 -- point of completion must match (SPARK RM 6.9(14)).
4179 if Present (Prev_Entity) and then Is_Ghost_Entity (Prev_Entity) then
4180 Check_Ghost_Completion (Prev_Entity, Id);
4184 -- Deal with aliased case
4186 if Aliased_Present (N) then
4187 Set_Is_Aliased (Id);
4189 -- If the object is aliased and the type is unconstrained with
4190 -- defaulted discriminants and there is no expression, then the
4191 -- object is constrained by the defaults, so it is worthwhile
4192 -- building the corresponding subtype.
4194 -- Ada 2005 (AI-363): If the aliased object is discriminated and
4195 -- unconstrained, then only establish an actual subtype if the
4196 -- nominal subtype is indefinite. In definite cases the object is
4197 -- unconstrained in Ada 2005.
4200 and then Is_Record_Type (T)
4201 and then not Is_Constrained (T)
4202 and then Has_Discriminants (T)
4203 and then (Ada_Version < Ada_2005
4204 or else not Is_Definite_Subtype (T))
4206 Set_Actual_Subtype (Id, Build_Default_Subtype (T, N));
4210 -- Now we can set the type of the object
4212 Set_Etype (Id, Act_T);
4214 -- Non-constant object is marked to be treated as volatile if type is
4215 -- volatile and we clear the Current_Value setting that may have been
4216 -- set above. Doing so for constants isn't required and might interfere
4217 -- with possible uses of the object as a static expression in contexts
4218 -- incompatible with volatility (e.g. as a case-statement alternative).
4220 if Ekind (Id) /= E_Constant and then Treat_As_Volatile (Etype (Id)) then
4221 Set_Treat_As_Volatile (Id);
4222 Set_Current_Value (Id, Empty);
4225 -- Deal with controlled types
4227 if Has_Controlled_Component (Etype (Id))
4228 or else Is_Controlled (Etype (Id))
4230 if not Is_Library_Level_Entity (Id) then
4231 Check_Restriction (No_Nested_Finalization, N);
4233 Validate_Controlled_Object (Id);
4237 if Has_Task (Etype (Id)) then
4238 Check_Restriction (No_Tasking, N);
4240 -- Deal with counting max tasks
4242 -- Nothing to do if inside a generic
4244 if Inside_A_Generic then
4247 -- If library level entity, then count tasks
4249 elsif Is_Library_Level_Entity (Id) then
4250 Check_Restriction (Max_Tasks, N, Count_Tasks (Etype (Id)));
4252 -- If not library level entity, then indicate we don't know max
4253 -- tasks and also check task hierarchy restriction and blocking
4254 -- operation (since starting a task is definitely blocking).
4257 Check_Restriction (Max_Tasks, N);
4258 Check_Restriction (No_Task_Hierarchy, N);
4259 Check_Potentially_Blocking_Operation (N);
4262 -- A rather specialized test. If we see two tasks being declared
4263 -- of the same type in the same object declaration, and the task
4264 -- has an entry with an address clause, we know that program error
4265 -- will be raised at run time since we can't have two tasks with
4266 -- entries at the same address.
4268 if Is_Task_Type (Etype (Id)) and then More_Ids (N) then
4273 E := First_Entity (Etype (Id));
4274 while Present (E) loop
4275 if Ekind (E) = E_Entry
4276 and then Present (Get_Attribute_Definition_Clause
4277 (E, Attribute_Address))
4279 Error_Msg_Warn := SPARK_Mode /= On;
4281 ("more than one task with same entry address<<", N);
4282 Error_Msg_N ("\Program_Error [<<", N);
4284 Make_Raise_Program_Error (Loc,
4285 Reason => PE_Duplicated_Entry_Address));
4295 -- Some simple constant-propagation: if the expression is a constant
4296 -- string initialized with a literal, share the literal. This avoids
4300 and then Is_Entity_Name (E)
4301 and then Ekind (Entity (E)) = E_Constant
4302 and then Base_Type (Etype (E)) = Standard_String
4305 Val : constant Node_Id := Constant_Value (Entity (E));
4307 if Present (Val) and then Nkind (Val) = N_String_Literal then
4308 Rewrite (E, New_Copy (Val));
4313 -- Another optimization: if the nominal subtype is unconstrained and
4314 -- the expression is a function call that returns an unconstrained
4315 -- type, rewrite the declaration as a renaming of the result of the
4316 -- call. The exceptions below are cases where the copy is expected,
4317 -- either by the back end (Aliased case) or by the semantics, as for
4318 -- initializing controlled types or copying tags for classwide types.
4321 and then Nkind (E) = N_Explicit_Dereference
4322 and then Nkind (Original_Node (E)) = N_Function_Call
4323 and then not Is_Library_Level_Entity (Id)
4324 and then not Is_Constrained (Underlying_Type (T))
4325 and then not Is_Aliased (Id)
4326 and then not Is_Class_Wide_Type (T)
4327 and then not Is_Controlled_Active (T)
4328 and then not Has_Controlled_Component (Base_Type (T))
4329 and then Expander_Active
4332 Make_Object_Renaming_Declaration (Loc,
4333 Defining_Identifier => Id,
4334 Access_Definition => Empty,
4335 Subtype_Mark => New_Occurrence_Of
4336 (Base_Type (Etype (Id)), Loc),
4339 Set_Renamed_Object (Id, E);
4341 -- Force generation of debugging information for the constant and for
4342 -- the renamed function call.
4344 Set_Debug_Info_Needed (Id);
4345 Set_Debug_Info_Needed (Entity (Prefix (E)));
4348 if Present (Prev_Entity)
4349 and then Is_Frozen (Prev_Entity)
4350 and then not Error_Posted (Id)
4352 Error_Msg_N ("full constant declaration appears too late", N);
4355 Check_Eliminated (Id);
4357 -- Deal with setting In_Private_Part flag if in private part
4359 if Ekind (Scope (Id)) = E_Package
4360 and then In_Private_Part (Scope (Id))
4362 Set_In_Private_Part (Id);
4365 -- Check for violation of No_Local_Timing_Events
4367 if Restriction_Check_Required (No_Local_Timing_Events)
4368 and then not Is_Library_Level_Entity (Id)
4369 and then Is_RTE (Etype (Id), RE_Timing_Event)
4371 Check_Restriction (No_Local_Timing_Events, N);
4375 -- Initialize the refined state of a variable here because this is a
4376 -- common destination for legal and illegal object declarations.
4378 if Ekind (Id) = E_Variable then
4379 Set_Encapsulating_State (Id, Empty);
4382 if Has_Aspects (N) then
4383 Analyze_Aspect_Specifications (N, Id);
4386 Analyze_Dimension (N);
4388 -- Verify whether the object declaration introduces an illegal hidden
4389 -- state within a package subject to a null abstract state.
4391 if Ekind (Id) = E_Variable then
4392 Check_No_Hidden_State (Id);
4395 Ghost_Mode := Save_Ghost_Mode;
4396 end Analyze_Object_Declaration;
4398 ---------------------------
4399 -- Analyze_Others_Choice --
4400 ---------------------------
4402 -- Nothing to do for the others choice node itself, the semantic analysis
4403 -- of the others choice will occur as part of the processing of the parent
4405 procedure Analyze_Others_Choice (N : Node_Id) is
4406 pragma Warnings (Off, N);
4409 end Analyze_Others_Choice;
4411 -------------------------------------------
4412 -- Analyze_Private_Extension_Declaration --
4413 -------------------------------------------
4415 procedure Analyze_Private_Extension_Declaration (N : Node_Id) is
4416 Indic : constant Node_Id := Subtype_Indication (N);
4417 T : constant Entity_Id := Defining_Identifier (N);
4418 Parent_Base : Entity_Id;
4419 Parent_Type : Entity_Id;
4422 -- Ada 2005 (AI-251): Decorate all names in list of ancestor interfaces
4424 if Is_Non_Empty_List (Interface_List (N)) then
4430 Intf := First (Interface_List (N));
4431 while Present (Intf) loop
4432 T := Find_Type_Of_Subtype_Indic (Intf);
4434 Diagnose_Interface (Intf, T);
4440 Generate_Definition (T);
4442 -- For other than Ada 2012, just enter the name in the current scope
4444 if Ada_Version < Ada_2012 then
4447 -- Ada 2012 (AI05-0162): Enter the name in the current scope handling
4448 -- case of private type that completes an incomplete type.
4455 Prev := Find_Type_Name (N);
4457 pragma Assert (Prev = T
4458 or else (Ekind (Prev) = E_Incomplete_Type
4459 and then Present (Full_View (Prev))
4460 and then Full_View (Prev) = T));
4464 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
4465 Parent_Base := Base_Type (Parent_Type);
4467 if Parent_Type = Any_Type or else Etype (Parent_Type) = Any_Type then
4468 Set_Ekind (T, Ekind (Parent_Type));
4469 Set_Etype (T, Any_Type);
4472 elsif not Is_Tagged_Type (Parent_Type) then
4474 ("parent of type extension must be a tagged type ", Indic);
4477 elsif Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
4478 Error_Msg_N ("premature derivation of incomplete type", Indic);
4481 elsif Is_Concurrent_Type (Parent_Type) then
4483 ("parent type of a private extension cannot be "
4484 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
4486 Set_Etype (T, Any_Type);
4487 Set_Ekind (T, E_Limited_Private_Type);
4488 Set_Private_Dependents (T, New_Elmt_List);
4489 Set_Error_Posted (T);
4493 -- Perhaps the parent type should be changed to the class-wide type's
4494 -- specific type in this case to prevent cascading errors ???
4496 if Is_Class_Wide_Type (Parent_Type) then
4498 ("parent of type extension must not be a class-wide type", Indic);
4502 if (not Is_Package_Or_Generic_Package (Current_Scope)
4503 and then Nkind (Parent (N)) /= N_Generic_Subprogram_Declaration)
4504 or else In_Private_Part (Current_Scope)
4507 Error_Msg_N ("invalid context for private extension", N);
4510 -- Set common attributes
4512 Set_Is_Pure (T, Is_Pure (Current_Scope));
4513 Set_Scope (T, Current_Scope);
4514 Set_Ekind (T, E_Record_Type_With_Private);
4515 Init_Size_Align (T);
4516 Set_Default_SSO (T);
4518 Set_Etype (T, Parent_Base);
4519 Set_Has_Task (T, Has_Task (Parent_Base));
4520 Set_Has_Protected (T, Has_Task (Parent_Base));
4522 Set_Convention (T, Convention (Parent_Type));
4523 Set_First_Rep_Item (T, First_Rep_Item (Parent_Type));
4524 Set_Is_First_Subtype (T);
4525 Make_Class_Wide_Type (T);
4527 if Unknown_Discriminants_Present (N) then
4528 Set_Discriminant_Constraint (T, No_Elist);
4531 Build_Derived_Record_Type (N, Parent_Type, T);
4533 -- Propagate inherited invariant information. The new type has
4534 -- invariants, if the parent type has inheritable invariants,
4535 -- and these invariants can in turn be inherited.
4537 if Has_Inheritable_Invariants (Parent_Type) then
4538 Set_Has_Inheritable_Invariants (T);
4539 Set_Has_Invariants (T);
4542 -- Ada 2005 (AI-443): Synchronized private extension or a rewritten
4543 -- synchronized formal derived type.
4545 if Ada_Version >= Ada_2005 and then Synchronized_Present (N) then
4546 Set_Is_Limited_Record (T);
4548 -- Formal derived type case
4550 if Is_Generic_Type (T) then
4552 -- The parent must be a tagged limited type or a synchronized
4555 if (not Is_Tagged_Type (Parent_Type)
4556 or else not Is_Limited_Type (Parent_Type))
4558 (not Is_Interface (Parent_Type)
4559 or else not Is_Synchronized_Interface (Parent_Type))
4561 Error_Msg_NE ("parent type of & must be tagged limited " &
4562 "or synchronized", N, T);
4565 -- The progenitors (if any) must be limited or synchronized
4568 if Present (Interfaces (T)) then
4571 Iface_Elmt : Elmt_Id;
4574 Iface_Elmt := First_Elmt (Interfaces (T));
4575 while Present (Iface_Elmt) loop
4576 Iface := Node (Iface_Elmt);
4578 if not Is_Limited_Interface (Iface)
4579 and then not Is_Synchronized_Interface (Iface)
4581 Error_Msg_NE ("progenitor & must be limited " &
4582 "or synchronized", N, Iface);
4585 Next_Elmt (Iface_Elmt);
4590 -- Regular derived extension, the parent must be a limited or
4591 -- synchronized interface.
4594 if not Is_Interface (Parent_Type)
4595 or else (not Is_Limited_Interface (Parent_Type)
4596 and then not Is_Synchronized_Interface (Parent_Type))
4599 ("parent type of & must be limited interface", N, T);
4603 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
4604 -- extension with a synchronized parent must be explicitly declared
4605 -- synchronized, because the full view will be a synchronized type.
4606 -- This must be checked before the check for limited types below,
4607 -- to ensure that types declared limited are not allowed to extend
4608 -- synchronized interfaces.
4610 elsif Is_Interface (Parent_Type)
4611 and then Is_Synchronized_Interface (Parent_Type)
4612 and then not Synchronized_Present (N)
4615 ("private extension of& must be explicitly synchronized",
4618 elsif Limited_Present (N) then
4619 Set_Is_Limited_Record (T);
4621 if not Is_Limited_Type (Parent_Type)
4623 (not Is_Interface (Parent_Type)
4624 or else not Is_Limited_Interface (Parent_Type))
4626 Error_Msg_NE ("parent type& of limited extension must be limited",
4632 if Has_Aspects (N) then
4633 Analyze_Aspect_Specifications (N, T);
4635 end Analyze_Private_Extension_Declaration;
4637 ---------------------------------
4638 -- Analyze_Subtype_Declaration --
4639 ---------------------------------
4641 procedure Analyze_Subtype_Declaration
4643 Skip : Boolean := False)
4645 Id : constant Entity_Id := Defining_Identifier (N);
4646 R_Checks : Check_Result;
4650 Generate_Definition (Id);
4651 Set_Is_Pure (Id, Is_Pure (Current_Scope));
4652 Init_Size_Align (Id);
4654 -- The following guard condition on Enter_Name is to handle cases where
4655 -- the defining identifier has already been entered into the scope but
4656 -- the declaration as a whole needs to be analyzed.
4658 -- This case in particular happens for derived enumeration types. The
4659 -- derived enumeration type is processed as an inserted enumeration type
4660 -- declaration followed by a rewritten subtype declaration. The defining
4661 -- identifier, however, is entered into the name scope very early in the
4662 -- processing of the original type declaration and therefore needs to be
4663 -- avoided here, when the created subtype declaration is analyzed. (See
4664 -- Build_Derived_Types)
4666 -- This also happens when the full view of a private type is derived
4667 -- type with constraints. In this case the entity has been introduced
4668 -- in the private declaration.
4670 -- Finally this happens in some complex cases when validity checks are
4671 -- enabled, where the same subtype declaration may be analyzed twice.
4672 -- This can happen if the subtype is created by the pre-analysis of
4673 -- an attribute tht gives the range of a loop statement, and the loop
4674 -- itself appears within an if_statement that will be rewritten during
4678 or else (Present (Etype (Id))
4679 and then (Is_Private_Type (Etype (Id))
4680 or else Is_Task_Type (Etype (Id))
4681 or else Is_Rewrite_Substitution (N)))
4685 elsif Current_Entity (Id) = Id then
4692 T := Process_Subtype (Subtype_Indication (N), N, Id, 'P');
4694 -- Class-wide equivalent types of records with unknown discriminants
4695 -- involve the generation of an itype which serves as the private view
4696 -- of a constrained record subtype. In such cases the base type of the
4697 -- current subtype we are processing is the private itype. Use the full
4698 -- of the private itype when decorating various attributes.
4701 and then Is_Private_Type (T)
4702 and then Present (Full_View (T))
4707 -- Inherit common attributes
4709 Set_Is_Volatile (Id, Is_Volatile (T));
4710 Set_Treat_As_Volatile (Id, Treat_As_Volatile (T));
4711 Set_Is_Generic_Type (Id, Is_Generic_Type (Base_Type (T)));
4712 Set_Convention (Id, Convention (T));
4714 -- If ancestor has predicates then so does the subtype, and in addition
4715 -- we must delay the freeze to properly arrange predicate inheritance.
4717 -- The Ancestor_Type test is really unpleasant, there seem to be cases
4718 -- in which T = ID, so the above tests and assignments do nothing???
4720 if Has_Predicates (T)
4721 or else (Present (Ancestor_Subtype (T))
4722 and then Has_Predicates (Ancestor_Subtype (T)))
4724 Set_Has_Predicates (Id);
4725 Set_Has_Delayed_Freeze (Id);
4728 -- Subtype of Boolean cannot have a constraint in SPARK
4730 if Is_Boolean_Type (T)
4731 and then Nkind (Subtype_Indication (N)) = N_Subtype_Indication
4733 Check_SPARK_05_Restriction
4734 ("subtype of Boolean cannot have constraint", N);
4737 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4739 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
4745 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint then
4746 One_Cstr := First (Constraints (Cstr));
4747 while Present (One_Cstr) loop
4749 -- Index or discriminant constraint in SPARK must be a
4753 Nkind_In (One_Cstr, N_Identifier, N_Expanded_Name)
4755 Check_SPARK_05_Restriction
4756 ("subtype mark required", One_Cstr);
4758 -- String subtype must have a lower bound of 1 in SPARK.
4759 -- Note that we do not need to test for the non-static case
4760 -- here, since that was already taken care of in
4761 -- Process_Range_Expr_In_Decl.
4763 elsif Base_Type (T) = Standard_String then
4764 Get_Index_Bounds (One_Cstr, Low, High);
4766 if Is_OK_Static_Expression (Low)
4767 and then Expr_Value (Low) /= 1
4769 Check_SPARK_05_Restriction
4770 ("String subtype must have lower bound of 1", N);
4780 -- In the case where there is no constraint given in the subtype
4781 -- indication, Process_Subtype just returns the Subtype_Mark, so its
4782 -- semantic attributes must be established here.
4784 if Nkind (Subtype_Indication (N)) /= N_Subtype_Indication then
4785 Set_Etype (Id, Base_Type (T));
4787 -- Subtype of unconstrained array without constraint is not allowed
4790 if Is_Array_Type (T) and then not Is_Constrained (T) then
4791 Check_SPARK_05_Restriction
4792 ("subtype of unconstrained array must have constraint", N);
4797 Set_Ekind (Id, E_Array_Subtype);
4798 Copy_Array_Subtype_Attributes (Id, T);
4800 when Decimal_Fixed_Point_Kind =>
4801 Set_Ekind (Id, E_Decimal_Fixed_Point_Subtype);
4802 Set_Digits_Value (Id, Digits_Value (T));
4803 Set_Delta_Value (Id, Delta_Value (T));
4804 Set_Scale_Value (Id, Scale_Value (T));
4805 Set_Small_Value (Id, Small_Value (T));
4806 Set_Scalar_Range (Id, Scalar_Range (T));
4807 Set_Machine_Radix_10 (Id, Machine_Radix_10 (T));
4808 Set_Is_Constrained (Id, Is_Constrained (T));
4809 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4810 Set_RM_Size (Id, RM_Size (T));
4812 when Enumeration_Kind =>
4813 Set_Ekind (Id, E_Enumeration_Subtype);
4814 Set_First_Literal (Id, First_Literal (Base_Type (T)));
4815 Set_Scalar_Range (Id, Scalar_Range (T));
4816 Set_Is_Character_Type (Id, Is_Character_Type (T));
4817 Set_Is_Constrained (Id, Is_Constrained (T));
4818 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4819 Set_RM_Size (Id, RM_Size (T));
4820 Inherit_Predicate_Flags (Id, T);
4822 when Ordinary_Fixed_Point_Kind =>
4823 Set_Ekind (Id, E_Ordinary_Fixed_Point_Subtype);
4824 Set_Scalar_Range (Id, Scalar_Range (T));
4825 Set_Small_Value (Id, Small_Value (T));
4826 Set_Delta_Value (Id, Delta_Value (T));
4827 Set_Is_Constrained (Id, Is_Constrained (T));
4828 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4829 Set_RM_Size (Id, RM_Size (T));
4832 Set_Ekind (Id, E_Floating_Point_Subtype);
4833 Set_Scalar_Range (Id, Scalar_Range (T));
4834 Set_Digits_Value (Id, Digits_Value (T));
4835 Set_Is_Constrained (Id, Is_Constrained (T));
4837 when Signed_Integer_Kind =>
4838 Set_Ekind (Id, E_Signed_Integer_Subtype);
4839 Set_Scalar_Range (Id, Scalar_Range (T));
4840 Set_Is_Constrained (Id, Is_Constrained (T));
4841 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4842 Set_RM_Size (Id, RM_Size (T));
4843 Inherit_Predicate_Flags (Id, T);
4845 when Modular_Integer_Kind =>
4846 Set_Ekind (Id, E_Modular_Integer_Subtype);
4847 Set_Scalar_Range (Id, Scalar_Range (T));
4848 Set_Is_Constrained (Id, Is_Constrained (T));
4849 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4850 Set_RM_Size (Id, RM_Size (T));
4851 Inherit_Predicate_Flags (Id, T);
4853 when Class_Wide_Kind =>
4854 Set_Ekind (Id, E_Class_Wide_Subtype);
4855 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4856 Set_Cloned_Subtype (Id, T);
4857 Set_Is_Tagged_Type (Id, True);
4858 Set_Has_Unknown_Discriminants
4860 Set_No_Tagged_Streams_Pragma
4861 (Id, No_Tagged_Streams_Pragma (T));
4863 if Ekind (T) = E_Class_Wide_Subtype then
4864 Set_Equivalent_Type (Id, Equivalent_Type (T));
4867 when E_Record_Type | E_Record_Subtype =>
4868 Set_Ekind (Id, E_Record_Subtype);
4870 if Ekind (T) = E_Record_Subtype
4871 and then Present (Cloned_Subtype (T))
4873 Set_Cloned_Subtype (Id, Cloned_Subtype (T));
4875 Set_Cloned_Subtype (Id, T);
4878 Set_First_Entity (Id, First_Entity (T));
4879 Set_Last_Entity (Id, Last_Entity (T));
4880 Set_Has_Discriminants (Id, Has_Discriminants (T));
4881 Set_Is_Constrained (Id, Is_Constrained (T));
4882 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4883 Set_Has_Implicit_Dereference
4884 (Id, Has_Implicit_Dereference (T));
4885 Set_Has_Unknown_Discriminants
4886 (Id, Has_Unknown_Discriminants (T));
4888 if Has_Discriminants (T) then
4889 Set_Discriminant_Constraint
4890 (Id, Discriminant_Constraint (T));
4891 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4893 elsif Has_Unknown_Discriminants (Id) then
4894 Set_Discriminant_Constraint (Id, No_Elist);
4897 if Is_Tagged_Type (T) then
4898 Set_Is_Tagged_Type (Id, True);
4899 Set_No_Tagged_Streams_Pragma
4900 (Id, No_Tagged_Streams_Pragma (T));
4901 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4902 Set_Direct_Primitive_Operations
4903 (Id, Direct_Primitive_Operations (T));
4904 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4906 if Is_Interface (T) then
4907 Set_Is_Interface (Id);
4908 Set_Is_Limited_Interface (Id, Is_Limited_Interface (T));
4912 when Private_Kind =>
4913 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4914 Set_Has_Discriminants (Id, Has_Discriminants (T));
4915 Set_Is_Constrained (Id, Is_Constrained (T));
4916 Set_First_Entity (Id, First_Entity (T));
4917 Set_Last_Entity (Id, Last_Entity (T));
4918 Set_Private_Dependents (Id, New_Elmt_List);
4919 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4920 Set_Has_Implicit_Dereference
4921 (Id, Has_Implicit_Dereference (T));
4922 Set_Has_Unknown_Discriminants
4923 (Id, Has_Unknown_Discriminants (T));
4924 Set_Known_To_Have_Preelab_Init
4925 (Id, Known_To_Have_Preelab_Init (T));
4927 if Is_Tagged_Type (T) then
4928 Set_Is_Tagged_Type (Id);
4929 Set_No_Tagged_Streams_Pragma (Id,
4930 No_Tagged_Streams_Pragma (T));
4931 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4932 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4933 Set_Direct_Primitive_Operations (Id,
4934 Direct_Primitive_Operations (T));
4937 -- In general the attributes of the subtype of a private type
4938 -- are the attributes of the partial view of parent. However,
4939 -- the full view may be a discriminated type, and the subtype
4940 -- must share the discriminant constraint to generate correct
4941 -- calls to initialization procedures.
4943 if Has_Discriminants (T) then
4944 Set_Discriminant_Constraint
4945 (Id, Discriminant_Constraint (T));
4946 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4948 elsif Present (Full_View (T))
4949 and then Has_Discriminants (Full_View (T))
4951 Set_Discriminant_Constraint
4952 (Id, Discriminant_Constraint (Full_View (T)));
4953 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4955 -- This would seem semantically correct, but apparently
4956 -- generates spurious errors about missing components ???
4958 -- Set_Has_Discriminants (Id);
4961 Prepare_Private_Subtype_Completion (Id, N);
4963 -- If this is the subtype of a constrained private type with
4964 -- discriminants that has got a full view and we also have
4965 -- built a completion just above, show that the completion
4966 -- is a clone of the full view to the back-end.
4968 if Has_Discriminants (T)
4969 and then not Has_Unknown_Discriminants (T)
4970 and then not Is_Empty_Elmt_List (Discriminant_Constraint (T))
4971 and then Present (Full_View (T))
4972 and then Present (Full_View (Id))
4974 Set_Cloned_Subtype (Full_View (Id), Full_View (T));
4978 Set_Ekind (Id, E_Access_Subtype);
4979 Set_Is_Constrained (Id, Is_Constrained (T));
4980 Set_Is_Access_Constant
4981 (Id, Is_Access_Constant (T));
4982 Set_Directly_Designated_Type
4983 (Id, Designated_Type (T));
4984 Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T));
4986 -- A Pure library_item must not contain the declaration of a
4987 -- named access type, except within a subprogram, generic
4988 -- subprogram, task unit, or protected unit, or if it has
4989 -- a specified Storage_Size of zero (RM05-10.2.1(15.4-15.5)).
4991 if Comes_From_Source (Id)
4992 and then In_Pure_Unit
4993 and then not In_Subprogram_Task_Protected_Unit
4994 and then not No_Pool_Assigned (Id)
4997 ("named access types not allowed in pure unit", N);
5000 when Concurrent_Kind =>
5001 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
5002 Set_Corresponding_Record_Type (Id,
5003 Corresponding_Record_Type (T));
5004 Set_First_Entity (Id, First_Entity (T));
5005 Set_First_Private_Entity (Id, First_Private_Entity (T));
5006 Set_Has_Discriminants (Id, Has_Discriminants (T));
5007 Set_Is_Constrained (Id, Is_Constrained (T));
5008 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
5009 Set_Last_Entity (Id, Last_Entity (T));
5011 if Is_Tagged_Type (T) then
5012 Set_No_Tagged_Streams_Pragma
5013 (Id, No_Tagged_Streams_Pragma (T));
5016 if Has_Discriminants (T) then
5017 Set_Discriminant_Constraint
5018 (Id, Discriminant_Constraint (T));
5019 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5022 when Incomplete_Kind =>
5023 if Ada_Version >= Ada_2005 then
5025 -- In Ada 2005 an incomplete type can be explicitly tagged:
5026 -- propagate indication. Note that we also have to include
5027 -- subtypes for Ada 2012 extended use of incomplete types.
5029 Set_Ekind (Id, E_Incomplete_Subtype);
5030 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
5031 Set_Private_Dependents (Id, New_Elmt_List);
5033 if Is_Tagged_Type (Id) then
5034 Set_No_Tagged_Streams_Pragma
5035 (Id, No_Tagged_Streams_Pragma (T));
5036 Set_Direct_Primitive_Operations (Id, New_Elmt_List);
5039 -- Ada 2005 (AI-412): Decorate an incomplete subtype of an
5040 -- incomplete type visible through a limited with clause.
5042 if From_Limited_With (T)
5043 and then Present (Non_Limited_View (T))
5045 Set_From_Limited_With (Id);
5046 Set_Non_Limited_View (Id, Non_Limited_View (T));
5048 -- Ada 2005 (AI-412): Add the regular incomplete subtype
5049 -- to the private dependents of the original incomplete
5050 -- type for future transformation.
5053 Append_Elmt (Id, Private_Dependents (T));
5056 -- If the subtype name denotes an incomplete type an error
5057 -- was already reported by Process_Subtype.
5060 Set_Etype (Id, Any_Type);
5064 raise Program_Error;
5068 if Etype (Id) = Any_Type then
5072 -- Some common processing on all types
5074 Set_Size_Info (Id, T);
5075 Set_First_Rep_Item (Id, First_Rep_Item (T));
5077 -- If the parent type is a generic actual, so is the subtype. This may
5078 -- happen in a nested instance. Why Comes_From_Source test???
5080 if not Comes_From_Source (N) then
5081 Set_Is_Generic_Actual_Type (Id, Is_Generic_Actual_Type (T));
5086 Set_Is_Immediately_Visible (Id, True);
5087 Set_Depends_On_Private (Id, Has_Private_Component (T));
5088 Set_Is_Descendent_Of_Address (Id, Is_Descendent_Of_Address (T));
5090 if Is_Interface (T) then
5091 Set_Is_Interface (Id);
5094 if Present (Generic_Parent_Type (N))
5096 (Nkind (Parent (Generic_Parent_Type (N))) /=
5097 N_Formal_Type_Declaration
5098 or else Nkind (Formal_Type_Definition
5099 (Parent (Generic_Parent_Type (N)))) /=
5100 N_Formal_Private_Type_Definition)
5102 if Is_Tagged_Type (Id) then
5104 -- If this is a generic actual subtype for a synchronized type,
5105 -- the primitive operations are those of the corresponding record
5106 -- for which there is a separate subtype declaration.
5108 if Is_Concurrent_Type (Id) then
5110 elsif Is_Class_Wide_Type (Id) then
5111 Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T));
5113 Derive_Subprograms (Generic_Parent_Type (N), Id, T);
5116 elsif Scope (Etype (Id)) /= Standard_Standard then
5117 Derive_Subprograms (Generic_Parent_Type (N), Id);
5121 if Is_Private_Type (T) and then Present (Full_View (T)) then
5122 Conditional_Delay (Id, Full_View (T));
5124 -- The subtypes of components or subcomponents of protected types
5125 -- do not need freeze nodes, which would otherwise appear in the
5126 -- wrong scope (before the freeze node for the protected type). The
5127 -- proper subtypes are those of the subcomponents of the corresponding
5130 elsif Ekind (Scope (Id)) /= E_Protected_Type
5131 and then Present (Scope (Scope (Id))) -- error defense
5132 and then Ekind (Scope (Scope (Id))) /= E_Protected_Type
5134 Conditional_Delay (Id, T);
5137 -- Check that Constraint_Error is raised for a scalar subtype indication
5138 -- when the lower or upper bound of a non-null range lies outside the
5139 -- range of the type mark.
5141 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5142 if Is_Scalar_Type (Etype (Id))
5143 and then Scalar_Range (Id) /=
5144 Scalar_Range (Etype (Subtype_Mark
5145 (Subtype_Indication (N))))
5149 Etype (Subtype_Mark (Subtype_Indication (N))));
5151 -- In the array case, check compatibility for each index
5153 elsif Is_Array_Type (Etype (Id)) and then Present (First_Index (Id))
5155 -- This really should be a subprogram that finds the indications
5159 Subt_Index : Node_Id := First_Index (Id);
5160 Target_Index : Node_Id :=
5162 (Subtype_Mark (Subtype_Indication (N))));
5163 Has_Dyn_Chk : Boolean := Has_Dynamic_Range_Check (N);
5166 while Present (Subt_Index) loop
5167 if ((Nkind (Subt_Index) = N_Identifier
5168 and then Ekind (Entity (Subt_Index)) in Scalar_Kind)
5169 or else Nkind (Subt_Index) = N_Subtype_Indication)
5171 Nkind (Scalar_Range (Etype (Subt_Index))) = N_Range
5174 Target_Typ : constant Entity_Id :=
5175 Etype (Target_Index);
5179 (Scalar_Range (Etype (Subt_Index)),
5182 Defining_Identifier (N));
5184 -- Reset Has_Dynamic_Range_Check on the subtype to
5185 -- prevent elision of the index check due to a dynamic
5186 -- check generated for a preceding index (needed since
5187 -- Insert_Range_Checks tries to avoid generating
5188 -- redundant checks on a given declaration).
5190 Set_Has_Dynamic_Range_Check (N, False);
5196 Sloc (Defining_Identifier (N)));
5198 -- Record whether this index involved a dynamic check
5201 Has_Dyn_Chk or else Has_Dynamic_Range_Check (N);
5205 Next_Index (Subt_Index);
5206 Next_Index (Target_Index);
5209 -- Finally, mark whether the subtype involves dynamic checks
5211 Set_Has_Dynamic_Range_Check (N, Has_Dyn_Chk);
5216 -- A type invariant applies to any subtype in its scope, in particular
5217 -- to a generic actual.
5219 if Has_Invariants (T) and then In_Open_Scopes (Scope (T)) then
5220 Set_Has_Invariants (Id);
5221 Set_Invariant_Procedure (Id, Invariant_Procedure (T));
5224 -- Make sure that generic actual types are properly frozen. The subtype
5225 -- is marked as a generic actual type when the enclosing instance is
5226 -- analyzed, so here we identify the subtype from the tree structure.
5229 and then Is_Generic_Actual_Type (Id)
5230 and then In_Instance
5231 and then not Comes_From_Source (N)
5232 and then Nkind (Subtype_Indication (N)) /= N_Subtype_Indication
5233 and then Is_Frozen (T)
5235 Freeze_Before (N, Id);
5238 Set_Optimize_Alignment_Flags (Id);
5239 Check_Eliminated (Id);
5242 if Has_Aspects (N) then
5243 Analyze_Aspect_Specifications (N, Id);
5246 Analyze_Dimension (N);
5248 -- Check No_Dynamic_Sized_Objects restriction, which disallows subtype
5249 -- indications on composite types where the constraints are dynamic.
5250 -- Note that object declarations and aggregates generate implicit
5251 -- subtype declarations, which this covers. One special case is that the
5252 -- implicitly generated "=" for discriminated types includes an
5253 -- offending subtype declaration, which is harmless, so we ignore it
5256 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5258 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
5260 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint
5261 and then not (Is_Internal (Id)
5262 and then Is_TSS (Scope (Id),
5263 TSS_Composite_Equality))
5264 and then not Within_Init_Proc
5265 and then not All_Composite_Constraints_Static (Cstr)
5267 Check_Restriction (No_Dynamic_Sized_Objects, Cstr);
5271 end Analyze_Subtype_Declaration;
5273 --------------------------------
5274 -- Analyze_Subtype_Indication --
5275 --------------------------------
5277 procedure Analyze_Subtype_Indication (N : Node_Id) is
5278 T : constant Entity_Id := Subtype_Mark (N);
5279 R : constant Node_Id := Range_Expression (Constraint (N));
5286 Set_Etype (N, Etype (R));
5287 Resolve (R, Entity (T));
5289 Set_Error_Posted (R);
5290 Set_Error_Posted (T);
5292 end Analyze_Subtype_Indication;
5294 --------------------------
5295 -- Analyze_Variant_Part --
5296 --------------------------
5298 procedure Analyze_Variant_Part (N : Node_Id) is
5299 Discr_Name : Node_Id;
5300 Discr_Type : Entity_Id;
5302 procedure Process_Variant (A : Node_Id);
5303 -- Analyze declarations for a single variant
5305 package Analyze_Variant_Choices is
5306 new Generic_Analyze_Choices (Process_Variant);
5307 use Analyze_Variant_Choices;
5309 ---------------------
5310 -- Process_Variant --
5311 ---------------------
5313 procedure Process_Variant (A : Node_Id) is
5314 CL : constant Node_Id := Component_List (A);
5316 if not Null_Present (CL) then
5317 Analyze_Declarations (Component_Items (CL));
5319 if Present (Variant_Part (CL)) then
5320 Analyze (Variant_Part (CL));
5323 end Process_Variant;
5325 -- Start of processing for Analyze_Variant_Part
5328 Discr_Name := Name (N);
5329 Analyze (Discr_Name);
5331 -- If Discr_Name bad, get out (prevent cascaded errors)
5333 if Etype (Discr_Name) = Any_Type then
5337 -- Check invalid discriminant in variant part
5339 if Ekind (Entity (Discr_Name)) /= E_Discriminant then
5340 Error_Msg_N ("invalid discriminant name in variant part", Discr_Name);
5343 Discr_Type := Etype (Entity (Discr_Name));
5345 if not Is_Discrete_Type (Discr_Type) then
5347 ("discriminant in a variant part must be of a discrete type",
5352 -- Now analyze the choices, which also analyzes the declarations that
5353 -- are associated with each choice.
5355 Analyze_Choices (Variants (N), Discr_Type);
5357 -- Note: we used to instantiate and call Check_Choices here to check
5358 -- that the choices covered the discriminant, but it's too early to do
5359 -- that because of statically predicated subtypes, whose analysis may
5360 -- be deferred to their freeze point which may be as late as the freeze
5361 -- point of the containing record. So this call is now to be found in
5362 -- Freeze_Record_Declaration.
5364 end Analyze_Variant_Part;
5366 ----------------------------
5367 -- Array_Type_Declaration --
5368 ----------------------------
5370 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is
5371 Component_Def : constant Node_Id := Component_Definition (Def);
5372 Component_Typ : constant Node_Id := Subtype_Indication (Component_Def);
5373 Element_Type : Entity_Id;
5374 Implicit_Base : Entity_Id;
5376 Related_Id : Entity_Id := Empty;
5378 P : constant Node_Id := Parent (Def);
5382 if Nkind (Def) = N_Constrained_Array_Definition then
5383 Index := First (Discrete_Subtype_Definitions (Def));
5385 Index := First (Subtype_Marks (Def));
5388 -- Find proper names for the implicit types which may be public. In case
5389 -- of anonymous arrays we use the name of the first object of that type
5393 Related_Id := Defining_Identifier (P);
5399 while Present (Index) loop
5402 -- Test for odd case of trying to index a type by the type itself
5404 if Is_Entity_Name (Index) and then Entity (Index) = T then
5405 Error_Msg_N ("type& cannot be indexed by itself", Index);
5406 Set_Entity (Index, Standard_Boolean);
5407 Set_Etype (Index, Standard_Boolean);
5410 -- Check SPARK restriction requiring a subtype mark
5412 if not Nkind_In (Index, N_Identifier, N_Expanded_Name) then
5413 Check_SPARK_05_Restriction ("subtype mark required", Index);
5416 -- Add a subtype declaration for each index of private array type
5417 -- declaration whose etype is also private. For example:
5420 -- type Index is private;
5422 -- type Table is array (Index) of ...
5425 -- This is currently required by the expander for the internally
5426 -- generated equality subprogram of records with variant parts in
5427 -- which the etype of some component is such private type.
5429 if Ekind (Current_Scope) = E_Package
5430 and then In_Private_Part (Current_Scope)
5431 and then Has_Private_Declaration (Etype (Index))
5434 Loc : constant Source_Ptr := Sloc (Def);
5439 New_E := Make_Temporary (Loc, 'T');
5440 Set_Is_Internal (New_E);
5443 Make_Subtype_Declaration (Loc,
5444 Defining_Identifier => New_E,
5445 Subtype_Indication =>
5446 New_Occurrence_Of (Etype (Index), Loc));
5448 Insert_Before (Parent (Def), Decl);
5450 Set_Etype (Index, New_E);
5452 -- If the index is a range the Entity attribute is not
5453 -- available. Example:
5456 -- type T is private;
5458 -- type T is new Natural;
5459 -- Table : array (T(1) .. T(10)) of Boolean;
5462 if Nkind (Index) /= N_Range then
5463 Set_Entity (Index, New_E);
5468 Make_Index (Index, P, Related_Id, Nb_Index);
5470 -- Check error of subtype with predicate for index type
5472 Bad_Predicated_Subtype_Use
5473 ("subtype& has predicate, not allowed as index subtype",
5474 Index, Etype (Index));
5476 -- Move to next index
5479 Nb_Index := Nb_Index + 1;
5482 -- Process subtype indication if one is present
5484 if Present (Component_Typ) then
5485 Element_Type := Process_Subtype (Component_Typ, P, Related_Id, 'C');
5487 Set_Etype (Component_Typ, Element_Type);
5489 if not Nkind_In (Component_Typ, N_Identifier, N_Expanded_Name) then
5490 Check_SPARK_05_Restriction
5491 ("subtype mark required", Component_Typ);
5494 -- Ada 2005 (AI-230): Access Definition case
5496 else pragma Assert (Present (Access_Definition (Component_Def)));
5498 -- Indicate that the anonymous access type is created by the
5499 -- array type declaration.
5501 Element_Type := Access_Definition
5503 N => Access_Definition (Component_Def));
5504 Set_Is_Local_Anonymous_Access (Element_Type);
5506 -- Propagate the parent. This field is needed if we have to generate
5507 -- the master_id associated with an anonymous access to task type
5508 -- component (see Expand_N_Full_Type_Declaration.Build_Master)
5510 Set_Parent (Element_Type, Parent (T));
5512 -- Ada 2005 (AI-230): In case of components that are anonymous access
5513 -- types the level of accessibility depends on the enclosing type
5516 Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230)
5518 -- Ada 2005 (AI-254)
5521 CD : constant Node_Id :=
5522 Access_To_Subprogram_Definition
5523 (Access_Definition (Component_Def));
5525 if Present (CD) and then Protected_Present (CD) then
5527 Replace_Anonymous_Access_To_Protected_Subprogram (Def);
5532 -- Constrained array case
5535 T := Create_Itype (E_Void, P, Related_Id, 'T');
5538 if Nkind (Def) = N_Constrained_Array_Definition then
5540 -- Establish Implicit_Base as unconstrained base type
5542 Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B');
5544 Set_Etype (Implicit_Base, Implicit_Base);
5545 Set_Scope (Implicit_Base, Current_Scope);
5546 Set_Has_Delayed_Freeze (Implicit_Base);
5547 Set_Default_SSO (Implicit_Base);
5549 -- The constrained array type is a subtype of the unconstrained one
5551 Set_Ekind (T, E_Array_Subtype);
5552 Init_Size_Align (T);
5553 Set_Etype (T, Implicit_Base);
5554 Set_Scope (T, Current_Scope);
5555 Set_Is_Constrained (T);
5557 First (Discrete_Subtype_Definitions (Def)));
5558 Set_Has_Delayed_Freeze (T);
5560 -- Complete setup of implicit base type
5562 Set_First_Index (Implicit_Base, First_Index (T));
5563 Set_Component_Type (Implicit_Base, Element_Type);
5564 Set_Has_Task (Implicit_Base, Has_Task (Element_Type));
5565 Set_Has_Protected (Implicit_Base, Has_Protected (Element_Type));
5566 Set_Component_Size (Implicit_Base, Uint_0);
5567 Set_Packed_Array_Impl_Type (Implicit_Base, Empty);
5568 Set_Has_Controlled_Component (Implicit_Base,
5569 Has_Controlled_Component (Element_Type)
5570 or else Is_Controlled_Active (Element_Type));
5571 Set_Finalize_Storage_Only (Implicit_Base,
5572 Finalize_Storage_Only (Element_Type));
5574 -- Inherit the "ghostness" from the constrained array type
5576 if Ghost_Mode > None or else Is_Ghost_Entity (T) then
5577 Set_Is_Ghost_Entity (Implicit_Base);
5580 -- Unconstrained array case
5583 Set_Ekind (T, E_Array_Type);
5584 Init_Size_Align (T);
5586 Set_Scope (T, Current_Scope);
5587 Set_Component_Size (T, Uint_0);
5588 Set_Is_Constrained (T, False);
5589 Set_First_Index (T, First (Subtype_Marks (Def)));
5590 Set_Has_Delayed_Freeze (T, True);
5591 Set_Has_Task (T, Has_Task (Element_Type));
5592 Set_Has_Protected (T, Has_Protected (Element_Type));
5593 Set_Has_Controlled_Component (T, Has_Controlled_Component
5596 Is_Controlled_Active (Element_Type));
5597 Set_Finalize_Storage_Only (T, Finalize_Storage_Only
5599 Set_Default_SSO (T);
5602 -- Common attributes for both cases
5604 Set_Component_Type (Base_Type (T), Element_Type);
5605 Set_Packed_Array_Impl_Type (T, Empty);
5607 if Aliased_Present (Component_Definition (Def)) then
5608 Check_SPARK_05_Restriction
5609 ("aliased is not allowed", Component_Definition (Def));
5610 Set_Has_Aliased_Components (Etype (T));
5613 -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the
5614 -- array type to ensure that objects of this type are initialized.
5616 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (Element_Type) then
5617 Set_Can_Never_Be_Null (T);
5619 if Null_Exclusion_Present (Component_Definition (Def))
5621 -- No need to check itypes because in their case this check was
5622 -- done at their point of creation
5624 and then not Is_Itype (Element_Type)
5627 ("`NOT NULL` not allowed (null already excluded)",
5628 Subtype_Indication (Component_Definition (Def)));
5632 Priv := Private_Component (Element_Type);
5634 if Present (Priv) then
5636 -- Check for circular definitions
5638 if Priv = Any_Type then
5639 Set_Component_Type (Etype (T), Any_Type);
5641 -- There is a gap in the visibility of operations on the composite
5642 -- type only if the component type is defined in a different scope.
5644 elsif Scope (Priv) = Current_Scope then
5647 elsif Is_Limited_Type (Priv) then
5648 Set_Is_Limited_Composite (Etype (T));
5649 Set_Is_Limited_Composite (T);
5651 Set_Is_Private_Composite (Etype (T));
5652 Set_Is_Private_Composite (T);
5656 -- A syntax error in the declaration itself may lead to an empty index
5657 -- list, in which case do a minimal patch.
5659 if No (First_Index (T)) then
5660 Error_Msg_N ("missing index definition in array type declaration", T);
5663 Indexes : constant List_Id :=
5664 New_List (New_Occurrence_Of (Any_Id, Sloc (T)));
5666 Set_Discrete_Subtype_Definitions (Def, Indexes);
5667 Set_First_Index (T, First (Indexes));
5672 -- Create a concatenation operator for the new type. Internal array
5673 -- types created for packed entities do not need such, they are
5674 -- compatible with the user-defined type.
5676 if Number_Dimensions (T) = 1
5677 and then not Is_Packed_Array_Impl_Type (T)
5679 New_Concatenation_Op (T);
5682 -- In the case of an unconstrained array the parser has already verified
5683 -- that all the indexes are unconstrained but we still need to make sure
5684 -- that the element type is constrained.
5686 if not Is_Definite_Subtype (Element_Type) then
5688 ("unconstrained element type in array declaration",
5689 Subtype_Indication (Component_Def));
5691 elsif Is_Abstract_Type (Element_Type) then
5693 ("the type of a component cannot be abstract",
5694 Subtype_Indication (Component_Def));
5697 -- There may be an invariant declared for the component type, but
5698 -- the construction of the component invariant checking procedure
5699 -- takes place during expansion.
5700 end Array_Type_Declaration;
5702 ------------------------------------------------------
5703 -- Replace_Anonymous_Access_To_Protected_Subprogram --
5704 ------------------------------------------------------
5706 function Replace_Anonymous_Access_To_Protected_Subprogram
5707 (N : Node_Id) return Entity_Id
5709 Loc : constant Source_Ptr := Sloc (N);
5711 Curr_Scope : constant Scope_Stack_Entry :=
5712 Scope_Stack.Table (Scope_Stack.Last);
5714 Anon : constant Entity_Id := Make_Temporary (Loc, 'S');
5717 -- Access definition in declaration
5720 -- Object definition or formal definition with an access definition
5723 -- Declaration of anonymous access to subprogram type
5726 -- Original specification in access to subprogram
5731 Set_Is_Internal (Anon);
5734 when N_Component_Declaration |
5735 N_Unconstrained_Array_Definition |
5736 N_Constrained_Array_Definition =>
5737 Comp := Component_Definition (N);
5738 Acc := Access_Definition (Comp);
5740 when N_Discriminant_Specification =>
5741 Comp := Discriminant_Type (N);
5744 when N_Parameter_Specification =>
5745 Comp := Parameter_Type (N);
5748 when N_Access_Function_Definition =>
5749 Comp := Result_Definition (N);
5752 when N_Object_Declaration =>
5753 Comp := Object_Definition (N);
5756 when N_Function_Specification =>
5757 Comp := Result_Definition (N);
5761 raise Program_Error;
5764 Spec := Access_To_Subprogram_Definition (Acc);
5767 Make_Full_Type_Declaration (Loc,
5768 Defining_Identifier => Anon,
5769 Type_Definition => Copy_Separate_Tree (Spec));
5771 Mark_Rewrite_Insertion (Decl);
5773 -- In ASIS mode, analyze the profile on the original node, because
5774 -- the separate copy does not provide enough links to recover the
5775 -- original tree. Analysis is limited to type annotations, within
5776 -- a temporary scope that serves as an anonymous subprogram to collect
5777 -- otherwise useless temporaries and itypes.
5781 Typ : constant Entity_Id := Make_Temporary (Loc, 'S');
5784 if Nkind (Spec) = N_Access_Function_Definition then
5785 Set_Ekind (Typ, E_Function);
5787 Set_Ekind (Typ, E_Procedure);
5790 Set_Parent (Typ, N);
5791 Set_Scope (Typ, Current_Scope);
5794 -- Nothing to do if procedure is parameterless
5796 if Present (Parameter_Specifications (Spec)) then
5797 Process_Formals (Parameter_Specifications (Spec), Spec);
5800 if Nkind (Spec) = N_Access_Function_Definition then
5802 Def : constant Node_Id := Result_Definition (Spec);
5805 -- The result might itself be an anonymous access type, so
5808 if Nkind (Def) = N_Access_Definition then
5809 if Present (Access_To_Subprogram_Definition (Def)) then
5812 Replace_Anonymous_Access_To_Protected_Subprogram
5815 Find_Type (Subtype_Mark (Def));
5828 -- Insert the new declaration in the nearest enclosing scope. If the
5829 -- node is a body and N is its return type, the declaration belongs in
5830 -- the enclosing scope.
5834 if Nkind (P) = N_Subprogram_Body
5835 and then Nkind (N) = N_Function_Specification
5840 while Present (P) and then not Has_Declarations (P) loop
5844 pragma Assert (Present (P));
5846 if Nkind (P) = N_Package_Specification then
5847 Prepend (Decl, Visible_Declarations (P));
5849 Prepend (Decl, Declarations (P));
5852 -- Replace the anonymous type with an occurrence of the new declaration.
5853 -- In all cases the rewritten node does not have the null-exclusion
5854 -- attribute because (if present) it was already inherited by the
5855 -- anonymous entity (Anon). Thus, in case of components we do not
5856 -- inherit this attribute.
5858 if Nkind (N) = N_Parameter_Specification then
5859 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5860 Set_Etype (Defining_Identifier (N), Anon);
5861 Set_Null_Exclusion_Present (N, False);
5863 elsif Nkind (N) = N_Object_Declaration then
5864 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5865 Set_Etype (Defining_Identifier (N), Anon);
5867 elsif Nkind (N) = N_Access_Function_Definition then
5868 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5870 elsif Nkind (N) = N_Function_Specification then
5871 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5872 Set_Etype (Defining_Unit_Name (N), Anon);
5876 Make_Component_Definition (Loc,
5877 Subtype_Indication => New_Occurrence_Of (Anon, Loc)));
5880 Mark_Rewrite_Insertion (Comp);
5882 if Nkind_In (N, N_Object_Declaration, N_Access_Function_Definition)
5883 or else (Nkind (Parent (N)) = N_Full_Type_Declaration
5884 and then not Is_Type (Current_Scope))
5887 -- Declaration can be analyzed in the current scope.
5892 -- Temporarily remove the current scope (record or subprogram) from
5893 -- the stack to add the new declarations to the enclosing scope.
5894 -- The anonymous entity is an Itype with the proper attributes.
5896 Scope_Stack.Decrement_Last;
5898 Set_Is_Itype (Anon);
5899 Set_Associated_Node_For_Itype (Anon, N);
5900 Scope_Stack.Append (Curr_Scope);
5903 Set_Ekind (Anon, E_Anonymous_Access_Protected_Subprogram_Type);
5904 Set_Can_Use_Internal_Rep (Anon, not Always_Compatible_Rep_On_Target);
5906 end Replace_Anonymous_Access_To_Protected_Subprogram;
5908 -------------------------------
5909 -- Build_Derived_Access_Type --
5910 -------------------------------
5912 procedure Build_Derived_Access_Type
5914 Parent_Type : Entity_Id;
5915 Derived_Type : Entity_Id)
5917 S : constant Node_Id := Subtype_Indication (Type_Definition (N));
5919 Desig_Type : Entity_Id;
5921 Discr_Con_Elist : Elist_Id;
5922 Discr_Con_El : Elmt_Id;
5926 -- Set the designated type so it is available in case this is an access
5927 -- to a self-referential type, e.g. a standard list type with a next
5928 -- pointer. Will be reset after subtype is built.
5930 Set_Directly_Designated_Type
5931 (Derived_Type, Designated_Type (Parent_Type));
5933 Subt := Process_Subtype (S, N);
5935 if Nkind (S) /= N_Subtype_Indication
5936 and then Subt /= Base_Type (Subt)
5938 Set_Ekind (Derived_Type, E_Access_Subtype);
5941 if Ekind (Derived_Type) = E_Access_Subtype then
5943 Pbase : constant Entity_Id := Base_Type (Parent_Type);
5944 Ibase : constant Entity_Id :=
5945 Create_Itype (Ekind (Pbase), N, Derived_Type, 'B');
5946 Svg_Chars : constant Name_Id := Chars (Ibase);
5947 Svg_Next_E : constant Entity_Id := Next_Entity (Ibase);
5950 Copy_Node (Pbase, Ibase);
5952 Set_Chars (Ibase, Svg_Chars);
5953 Set_Next_Entity (Ibase, Svg_Next_E);
5954 Set_Sloc (Ibase, Sloc (Derived_Type));
5955 Set_Scope (Ibase, Scope (Derived_Type));
5956 Set_Freeze_Node (Ibase, Empty);
5957 Set_Is_Frozen (Ibase, False);
5958 Set_Comes_From_Source (Ibase, False);
5959 Set_Is_First_Subtype (Ibase, False);
5961 Set_Etype (Ibase, Pbase);
5962 Set_Etype (Derived_Type, Ibase);
5966 Set_Directly_Designated_Type
5967 (Derived_Type, Designated_Type (Subt));
5969 Set_Is_Constrained (Derived_Type, Is_Constrained (Subt));
5970 Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type));
5971 Set_Size_Info (Derived_Type, Parent_Type);
5972 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
5973 Set_Depends_On_Private (Derived_Type,
5974 Has_Private_Component (Derived_Type));
5975 Conditional_Delay (Derived_Type, Subt);
5977 -- Ada 2005 (AI-231): Set the null-exclusion attribute, and verify
5978 -- that it is not redundant.
5980 if Null_Exclusion_Present (Type_Definition (N)) then
5981 Set_Can_Never_Be_Null (Derived_Type);
5983 -- What is with the "AND THEN FALSE" here ???
5985 if Can_Never_Be_Null (Parent_Type)
5989 ("`NOT NULL` not allowed (& already excludes null)",
5993 elsif Can_Never_Be_Null (Parent_Type) then
5994 Set_Can_Never_Be_Null (Derived_Type);
5997 -- Note: we do not copy the Storage_Size_Variable, since we always go to
5998 -- the root type for this information.
6000 -- Apply range checks to discriminants for derived record case
6001 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
6003 Desig_Type := Designated_Type (Derived_Type);
6004 if Is_Composite_Type (Desig_Type)
6005 and then (not Is_Array_Type (Desig_Type))
6006 and then Has_Discriminants (Desig_Type)
6007 and then Base_Type (Desig_Type) /= Desig_Type
6009 Discr_Con_Elist := Discriminant_Constraint (Desig_Type);
6010 Discr_Con_El := First_Elmt (Discr_Con_Elist);
6012 Discr := First_Discriminant (Base_Type (Desig_Type));
6013 while Present (Discr_Con_El) loop
6014 Apply_Range_Check (Node (Discr_Con_El), Etype (Discr));
6015 Next_Elmt (Discr_Con_El);
6016 Next_Discriminant (Discr);
6019 end Build_Derived_Access_Type;
6021 ------------------------------
6022 -- Build_Derived_Array_Type --
6023 ------------------------------
6025 procedure Build_Derived_Array_Type
6027 Parent_Type : Entity_Id;
6028 Derived_Type : Entity_Id)
6030 Loc : constant Source_Ptr := Sloc (N);
6031 Tdef : constant Node_Id := Type_Definition (N);
6032 Indic : constant Node_Id := Subtype_Indication (Tdef);
6033 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
6034 Implicit_Base : Entity_Id;
6035 New_Indic : Node_Id;
6037 procedure Make_Implicit_Base;
6038 -- If the parent subtype is constrained, the derived type is a subtype
6039 -- of an implicit base type derived from the parent base.
6041 ------------------------
6042 -- Make_Implicit_Base --
6043 ------------------------
6045 procedure Make_Implicit_Base is
6048 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
6050 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
6051 Set_Etype (Implicit_Base, Parent_Base);
6053 Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base);
6054 Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base);
6056 Set_Has_Delayed_Freeze (Implicit_Base, True);
6058 -- Inherit the "ghostness" from the parent base type
6060 if Ghost_Mode > None or else Is_Ghost_Entity (Parent_Base) then
6061 Set_Is_Ghost_Entity (Implicit_Base);
6063 end Make_Implicit_Base;
6065 -- Start of processing for Build_Derived_Array_Type
6068 if not Is_Constrained (Parent_Type) then
6069 if Nkind (Indic) /= N_Subtype_Indication then
6070 Set_Ekind (Derived_Type, E_Array_Type);
6072 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
6073 Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type);
6075 Set_Has_Delayed_Freeze (Derived_Type, True);
6079 Set_Etype (Derived_Type, Implicit_Base);
6082 Make_Subtype_Declaration (Loc,
6083 Defining_Identifier => Derived_Type,
6084 Subtype_Indication =>
6085 Make_Subtype_Indication (Loc,
6086 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6087 Constraint => Constraint (Indic)));
6089 Rewrite (N, New_Indic);
6094 if Nkind (Indic) /= N_Subtype_Indication then
6097 Set_Ekind (Derived_Type, Ekind (Parent_Type));
6098 Set_Etype (Derived_Type, Implicit_Base);
6099 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
6102 Error_Msg_N ("illegal constraint on constrained type", Indic);
6106 -- If parent type is not a derived type itself, and is declared in
6107 -- closed scope (e.g. a subprogram), then we must explicitly introduce
6108 -- the new type's concatenation operator since Derive_Subprograms
6109 -- will not inherit the parent's operator. If the parent type is
6110 -- unconstrained, the operator is of the unconstrained base type.
6112 if Number_Dimensions (Parent_Type) = 1
6113 and then not Is_Limited_Type (Parent_Type)
6114 and then not Is_Derived_Type (Parent_Type)
6115 and then not Is_Package_Or_Generic_Package
6116 (Scope (Base_Type (Parent_Type)))
6118 if not Is_Constrained (Parent_Type)
6119 and then Is_Constrained (Derived_Type)
6121 New_Concatenation_Op (Implicit_Base);
6123 New_Concatenation_Op (Derived_Type);
6126 end Build_Derived_Array_Type;
6128 -----------------------------------
6129 -- Build_Derived_Concurrent_Type --
6130 -----------------------------------
6132 procedure Build_Derived_Concurrent_Type
6134 Parent_Type : Entity_Id;
6135 Derived_Type : Entity_Id)
6137 Loc : constant Source_Ptr := Sloc (N);
6139 Corr_Record : constant Entity_Id := Make_Temporary (Loc, 'C');
6140 Corr_Decl : Node_Id;
6141 Corr_Decl_Needed : Boolean;
6142 -- If the derived type has fewer discriminants than its parent, the
6143 -- corresponding record is also a derived type, in order to account for
6144 -- the bound discriminants. We create a full type declaration for it in
6147 Constraint_Present : constant Boolean :=
6148 Nkind (Subtype_Indication (Type_Definition (N))) =
6149 N_Subtype_Indication;
6151 D_Constraint : Node_Id;
6152 New_Constraint : Elist_Id;
6153 Old_Disc : Entity_Id;
6154 New_Disc : Entity_Id;
6158 Set_Stored_Constraint (Derived_Type, No_Elist);
6159 Corr_Decl_Needed := False;
6162 if Present (Discriminant_Specifications (N))
6163 and then Constraint_Present
6165 Old_Disc := First_Discriminant (Parent_Type);
6166 New_Disc := First (Discriminant_Specifications (N));
6167 while Present (New_Disc) and then Present (Old_Disc) loop
6168 Next_Discriminant (Old_Disc);
6173 if Present (Old_Disc) and then Expander_Active then
6175 -- The new type has fewer discriminants, so we need to create a new
6176 -- corresponding record, which is derived from the corresponding
6177 -- record of the parent, and has a stored constraint that captures
6178 -- the values of the discriminant constraints. The corresponding
6179 -- record is needed only if expander is active and code generation is
6182 -- The type declaration for the derived corresponding record has the
6183 -- same discriminant part and constraints as the current declaration.
6184 -- Copy the unanalyzed tree to build declaration.
6186 Corr_Decl_Needed := True;
6187 New_N := Copy_Separate_Tree (N);
6190 Make_Full_Type_Declaration (Loc,
6191 Defining_Identifier => Corr_Record,
6192 Discriminant_Specifications =>
6193 Discriminant_Specifications (New_N),
6195 Make_Derived_Type_Definition (Loc,
6196 Subtype_Indication =>
6197 Make_Subtype_Indication (Loc,
6200 (Corresponding_Record_Type (Parent_Type), Loc),
6203 (Subtype_Indication (Type_Definition (New_N))))));
6206 -- Copy Storage_Size and Relative_Deadline variables if task case
6208 if Is_Task_Type (Parent_Type) then
6209 Set_Storage_Size_Variable (Derived_Type,
6210 Storage_Size_Variable (Parent_Type));
6211 Set_Relative_Deadline_Variable (Derived_Type,
6212 Relative_Deadline_Variable (Parent_Type));
6215 if Present (Discriminant_Specifications (N)) then
6216 Push_Scope (Derived_Type);
6217 Check_Or_Process_Discriminants (N, Derived_Type);
6219 if Constraint_Present then
6221 Expand_To_Stored_Constraint
6223 Build_Discriminant_Constraints
6225 Subtype_Indication (Type_Definition (N)), True));
6230 elsif Constraint_Present then
6232 -- Build constrained subtype, copying the constraint, and derive
6233 -- from it to create a derived constrained type.
6236 Loc : constant Source_Ptr := Sloc (N);
6237 Anon : constant Entity_Id :=
6238 Make_Defining_Identifier (Loc,
6239 Chars => New_External_Name (Chars (Derived_Type), 'T'));
6244 Make_Subtype_Declaration (Loc,
6245 Defining_Identifier => Anon,
6246 Subtype_Indication =>
6247 New_Copy_Tree (Subtype_Indication (Type_Definition (N))));
6248 Insert_Before (N, Decl);
6251 Rewrite (Subtype_Indication (Type_Definition (N)),
6252 New_Occurrence_Of (Anon, Loc));
6253 Set_Analyzed (Derived_Type, False);
6259 -- By default, operations and private data are inherited from parent.
6260 -- However, in the presence of bound discriminants, a new corresponding
6261 -- record will be created, see below.
6263 Set_Has_Discriminants
6264 (Derived_Type, Has_Discriminants (Parent_Type));
6265 Set_Corresponding_Record_Type
6266 (Derived_Type, Corresponding_Record_Type (Parent_Type));
6268 -- Is_Constrained is set according the parent subtype, but is set to
6269 -- False if the derived type is declared with new discriminants.
6273 (Is_Constrained (Parent_Type) or else Constraint_Present)
6274 and then not Present (Discriminant_Specifications (N)));
6276 if Constraint_Present then
6277 if not Has_Discriminants (Parent_Type) then
6278 Error_Msg_N ("untagged parent must have discriminants", N);
6280 elsif Present (Discriminant_Specifications (N)) then
6282 -- Verify that new discriminants are used to constrain old ones
6287 (Constraint (Subtype_Indication (Type_Definition (N)))));
6289 Old_Disc := First_Discriminant (Parent_Type);
6291 while Present (D_Constraint) loop
6292 if Nkind (D_Constraint) /= N_Discriminant_Association then
6294 -- Positional constraint. If it is a reference to a new
6295 -- discriminant, it constrains the corresponding old one.
6297 if Nkind (D_Constraint) = N_Identifier then
6298 New_Disc := First_Discriminant (Derived_Type);
6299 while Present (New_Disc) loop
6300 exit when Chars (New_Disc) = Chars (D_Constraint);
6301 Next_Discriminant (New_Disc);
6304 if Present (New_Disc) then
6305 Set_Corresponding_Discriminant (New_Disc, Old_Disc);
6309 Next_Discriminant (Old_Disc);
6311 -- if this is a named constraint, search by name for the old
6312 -- discriminants constrained by the new one.
6314 elsif Nkind (Expression (D_Constraint)) = N_Identifier then
6316 -- Find new discriminant with that name
6318 New_Disc := First_Discriminant (Derived_Type);
6319 while Present (New_Disc) loop
6321 Chars (New_Disc) = Chars (Expression (D_Constraint));
6322 Next_Discriminant (New_Disc);
6325 if Present (New_Disc) then
6327 -- Verify that new discriminant renames some discriminant
6328 -- of the parent type, and associate the new discriminant
6329 -- with one or more old ones that it renames.
6335 Selector := First (Selector_Names (D_Constraint));
6336 while Present (Selector) loop
6337 Old_Disc := First_Discriminant (Parent_Type);
6338 while Present (Old_Disc) loop
6339 exit when Chars (Old_Disc) = Chars (Selector);
6340 Next_Discriminant (Old_Disc);
6343 if Present (Old_Disc) then
6344 Set_Corresponding_Discriminant
6345 (New_Disc, Old_Disc);
6354 Next (D_Constraint);
6357 New_Disc := First_Discriminant (Derived_Type);
6358 while Present (New_Disc) loop
6359 if No (Corresponding_Discriminant (New_Disc)) then
6361 ("new discriminant& must constrain old one", N, New_Disc);
6364 Subtypes_Statically_Compatible
6366 Etype (Corresponding_Discriminant (New_Disc)))
6369 ("& not statically compatible with parent discriminant",
6373 Next_Discriminant (New_Disc);
6377 elsif Present (Discriminant_Specifications (N)) then
6379 ("missing discriminant constraint in untagged derivation", N);
6382 -- The entity chain of the derived type includes the new discriminants
6383 -- but shares operations with the parent.
6385 if Present (Discriminant_Specifications (N)) then
6386 Old_Disc := First_Discriminant (Parent_Type);
6387 while Present (Old_Disc) loop
6388 if No (Next_Entity (Old_Disc))
6389 or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant
6392 (Last_Entity (Derived_Type), Next_Entity (Old_Disc));
6396 Next_Discriminant (Old_Disc);
6400 Set_First_Entity (Derived_Type, First_Entity (Parent_Type));
6401 if Has_Discriminants (Parent_Type) then
6402 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6403 Set_Discriminant_Constraint (
6404 Derived_Type, Discriminant_Constraint (Parent_Type));
6408 Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type));
6410 Set_Has_Completion (Derived_Type);
6412 if Corr_Decl_Needed then
6413 Set_Stored_Constraint (Derived_Type, New_Constraint);
6414 Insert_After (N, Corr_Decl);
6415 Analyze (Corr_Decl);
6416 Set_Corresponding_Record_Type (Derived_Type, Corr_Record);
6418 end Build_Derived_Concurrent_Type;
6420 ------------------------------------
6421 -- Build_Derived_Enumeration_Type --
6422 ------------------------------------
6424 procedure Build_Derived_Enumeration_Type
6426 Parent_Type : Entity_Id;
6427 Derived_Type : Entity_Id)
6429 Loc : constant Source_Ptr := Sloc (N);
6430 Def : constant Node_Id := Type_Definition (N);
6431 Indic : constant Node_Id := Subtype_Indication (Def);
6432 Implicit_Base : Entity_Id;
6433 Literal : Entity_Id;
6434 New_Lit : Entity_Id;
6435 Literals_List : List_Id;
6436 Type_Decl : Node_Id;
6438 Rang_Expr : Node_Id;
6441 -- Since types Standard.Character and Standard.[Wide_]Wide_Character do
6442 -- not have explicit literals lists we need to process types derived
6443 -- from them specially. This is handled by Derived_Standard_Character.
6444 -- If the parent type is a generic type, there are no literals either,
6445 -- and we construct the same skeletal representation as for the generic
6448 if Is_Standard_Character_Type (Parent_Type) then
6449 Derived_Standard_Character (N, Parent_Type, Derived_Type);
6451 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
6457 if Nkind (Indic) /= N_Subtype_Indication then
6459 Make_Attribute_Reference (Loc,
6460 Attribute_Name => Name_First,
6461 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6462 Set_Etype (Lo, Derived_Type);
6465 Make_Attribute_Reference (Loc,
6466 Attribute_Name => Name_Last,
6467 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6468 Set_Etype (Hi, Derived_Type);
6470 Set_Scalar_Range (Derived_Type,
6476 -- Analyze subtype indication and verify compatibility
6477 -- with parent type.
6479 if Base_Type (Process_Subtype (Indic, N)) /=
6480 Base_Type (Parent_Type)
6483 ("illegal constraint for formal discrete type", N);
6489 -- If a constraint is present, analyze the bounds to catch
6490 -- premature usage of the derived literals.
6492 if Nkind (Indic) = N_Subtype_Indication
6493 and then Nkind (Range_Expression (Constraint (Indic))) = N_Range
6495 Analyze (Low_Bound (Range_Expression (Constraint (Indic))));
6496 Analyze (High_Bound (Range_Expression (Constraint (Indic))));
6499 -- Introduce an implicit base type for the derived type even if there
6500 -- is no constraint attached to it, since this seems closer to the
6501 -- Ada semantics. Build a full type declaration tree for the derived
6502 -- type using the implicit base type as the defining identifier. The
6503 -- build a subtype declaration tree which applies the constraint (if
6504 -- any) have it replace the derived type declaration.
6506 Literal := First_Literal (Parent_Type);
6507 Literals_List := New_List;
6508 while Present (Literal)
6509 and then Ekind (Literal) = E_Enumeration_Literal
6511 -- Literals of the derived type have the same representation as
6512 -- those of the parent type, but this representation can be
6513 -- overridden by an explicit representation clause. Indicate
6514 -- that there is no explicit representation given yet. These
6515 -- derived literals are implicit operations of the new type,
6516 -- and can be overridden by explicit ones.
6518 if Nkind (Literal) = N_Defining_Character_Literal then
6520 Make_Defining_Character_Literal (Loc, Chars (Literal));
6522 New_Lit := Make_Defining_Identifier (Loc, Chars (Literal));
6525 Set_Ekind (New_Lit, E_Enumeration_Literal);
6526 Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal));
6527 Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal));
6528 Set_Enumeration_Rep_Expr (New_Lit, Empty);
6529 Set_Alias (New_Lit, Literal);
6530 Set_Is_Known_Valid (New_Lit, True);
6532 Append (New_Lit, Literals_List);
6533 Next_Literal (Literal);
6537 Make_Defining_Identifier (Sloc (Derived_Type),
6538 Chars => New_External_Name (Chars (Derived_Type), 'B'));
6540 -- Indicate the proper nature of the derived type. This must be done
6541 -- before analysis of the literals, to recognize cases when a literal
6542 -- may be hidden by a previous explicit function definition (cf.
6545 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
6546 Set_Etype (Derived_Type, Implicit_Base);
6549 Make_Full_Type_Declaration (Loc,
6550 Defining_Identifier => Implicit_Base,
6551 Discriminant_Specifications => No_List,
6553 Make_Enumeration_Type_Definition (Loc, Literals_List));
6555 Mark_Rewrite_Insertion (Type_Decl);
6556 Insert_Before (N, Type_Decl);
6557 Analyze (Type_Decl);
6559 -- The anonymous base now has a full declaration, but this base
6560 -- is not a first subtype.
6562 Set_Is_First_Subtype (Implicit_Base, False);
6564 -- After the implicit base is analyzed its Etype needs to be changed
6565 -- to reflect the fact that it is derived from the parent type which
6566 -- was ignored during analysis. We also set the size at this point.
6568 Set_Etype (Implicit_Base, Parent_Type);
6570 Set_Size_Info (Implicit_Base, Parent_Type);
6571 Set_RM_Size (Implicit_Base, RM_Size (Parent_Type));
6572 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type));
6574 -- Copy other flags from parent type
6576 Set_Has_Non_Standard_Rep
6577 (Implicit_Base, Has_Non_Standard_Rep
6579 Set_Has_Pragma_Ordered
6580 (Implicit_Base, Has_Pragma_Ordered
6582 Set_Has_Delayed_Freeze (Implicit_Base);
6584 -- Process the subtype indication including a validation check on the
6585 -- constraint, if any. If a constraint is given, its bounds must be
6586 -- implicitly converted to the new type.
6588 if Nkind (Indic) = N_Subtype_Indication then
6590 R : constant Node_Id :=
6591 Range_Expression (Constraint (Indic));
6594 if Nkind (R) = N_Range then
6595 Hi := Build_Scalar_Bound
6596 (High_Bound (R), Parent_Type, Implicit_Base);
6597 Lo := Build_Scalar_Bound
6598 (Low_Bound (R), Parent_Type, Implicit_Base);
6601 -- Constraint is a Range attribute. Replace with explicit
6602 -- mention of the bounds of the prefix, which must be a
6605 Analyze (Prefix (R));
6607 Convert_To (Implicit_Base,
6608 Make_Attribute_Reference (Loc,
6609 Attribute_Name => Name_Last,
6611 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6614 Convert_To (Implicit_Base,
6615 Make_Attribute_Reference (Loc,
6616 Attribute_Name => Name_First,
6618 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6625 (Type_High_Bound (Parent_Type),
6626 Parent_Type, Implicit_Base);
6629 (Type_Low_Bound (Parent_Type),
6630 Parent_Type, Implicit_Base);
6638 -- If we constructed a default range for the case where no range
6639 -- was given, then the expressions in the range must not freeze
6640 -- since they do not correspond to expressions in the source.
6642 if Nkind (Indic) /= N_Subtype_Indication then
6643 Set_Must_Not_Freeze (Lo);
6644 Set_Must_Not_Freeze (Hi);
6645 Set_Must_Not_Freeze (Rang_Expr);
6649 Make_Subtype_Declaration (Loc,
6650 Defining_Identifier => Derived_Type,
6651 Subtype_Indication =>
6652 Make_Subtype_Indication (Loc,
6653 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6655 Make_Range_Constraint (Loc,
6656 Range_Expression => Rang_Expr))));
6660 -- Propagate the aspects from the original type declaration to the
6661 -- declaration of the implicit base.
6663 Move_Aspects (From => Original_Node (N), To => Type_Decl);
6665 -- Apply a range check. Since this range expression doesn't have an
6666 -- Etype, we have to specifically pass the Source_Typ parameter. Is
6669 if Nkind (Indic) = N_Subtype_Indication then
6671 (Range_Expression (Constraint (Indic)), Parent_Type,
6672 Source_Typ => Entity (Subtype_Mark (Indic)));
6675 end Build_Derived_Enumeration_Type;
6677 --------------------------------
6678 -- Build_Derived_Numeric_Type --
6679 --------------------------------
6681 procedure Build_Derived_Numeric_Type
6683 Parent_Type : Entity_Id;
6684 Derived_Type : Entity_Id)
6686 Loc : constant Source_Ptr := Sloc (N);
6687 Tdef : constant Node_Id := Type_Definition (N);
6688 Indic : constant Node_Id := Subtype_Indication (Tdef);
6689 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
6690 No_Constraint : constant Boolean := Nkind (Indic) /=
6691 N_Subtype_Indication;
6692 Implicit_Base : Entity_Id;
6698 -- Process the subtype indication including a validation check on
6699 -- the constraint if any.
6701 Discard_Node (Process_Subtype (Indic, N));
6703 -- Introduce an implicit base type for the derived type even if there
6704 -- is no constraint attached to it, since this seems closer to the Ada
6708 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
6710 Set_Etype (Implicit_Base, Parent_Base);
6711 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
6712 Set_Size_Info (Implicit_Base, Parent_Base);
6713 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base));
6714 Set_Parent (Implicit_Base, Parent (Derived_Type));
6715 Set_Is_Known_Valid (Implicit_Base, Is_Known_Valid (Parent_Base));
6717 -- Set RM Size for discrete type or decimal fixed-point type
6718 -- Ordinary fixed-point is excluded, why???
6720 if Is_Discrete_Type (Parent_Base)
6721 or else Is_Decimal_Fixed_Point_Type (Parent_Base)
6723 Set_RM_Size (Implicit_Base, RM_Size (Parent_Base));
6726 Set_Has_Delayed_Freeze (Implicit_Base);
6728 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
6729 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
6731 Set_Scalar_Range (Implicit_Base,
6736 if Has_Infinities (Parent_Base) then
6737 Set_Includes_Infinities (Scalar_Range (Implicit_Base));
6740 -- The Derived_Type, which is the entity of the declaration, is a
6741 -- subtype of the implicit base. Its Ekind is a subtype, even in the
6742 -- absence of an explicit constraint.
6744 Set_Etype (Derived_Type, Implicit_Base);
6746 -- If we did not have a constraint, then the Ekind is set from the
6747 -- parent type (otherwise Process_Subtype has set the bounds)
6749 if No_Constraint then
6750 Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type)));
6753 -- If we did not have a range constraint, then set the range from the
6754 -- parent type. Otherwise, the Process_Subtype call has set the bounds.
6756 if No_Constraint or else not Has_Range_Constraint (Indic) then
6757 Set_Scalar_Range (Derived_Type,
6759 Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)),
6760 High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type))));
6761 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6763 if Has_Infinities (Parent_Type) then
6764 Set_Includes_Infinities (Scalar_Range (Derived_Type));
6767 Set_Is_Known_Valid (Derived_Type, Is_Known_Valid (Parent_Type));
6770 Set_Is_Descendent_Of_Address (Derived_Type,
6771 Is_Descendent_Of_Address (Parent_Type));
6772 Set_Is_Descendent_Of_Address (Implicit_Base,
6773 Is_Descendent_Of_Address (Parent_Type));
6775 -- Set remaining type-specific fields, depending on numeric type
6777 if Is_Modular_Integer_Type (Parent_Type) then
6778 Set_Modulus (Implicit_Base, Modulus (Parent_Base));
6780 Set_Non_Binary_Modulus
6781 (Implicit_Base, Non_Binary_Modulus (Parent_Base));
6784 (Implicit_Base, Is_Known_Valid (Parent_Base));
6786 elsif Is_Floating_Point_Type (Parent_Type) then
6788 -- Digits of base type is always copied from the digits value of
6789 -- the parent base type, but the digits of the derived type will
6790 -- already have been set if there was a constraint present.
6792 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6793 Set_Float_Rep (Implicit_Base, Float_Rep (Parent_Base));
6795 if No_Constraint then
6796 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type));
6799 elsif Is_Fixed_Point_Type (Parent_Type) then
6801 -- Small of base type and derived type are always copied from the
6802 -- parent base type, since smalls never change. The delta of the
6803 -- base type is also copied from the parent base type. However the
6804 -- delta of the derived type will have been set already if a
6805 -- constraint was present.
6807 Set_Small_Value (Derived_Type, Small_Value (Parent_Base));
6808 Set_Small_Value (Implicit_Base, Small_Value (Parent_Base));
6809 Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base));
6811 if No_Constraint then
6812 Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type));
6815 -- The scale and machine radix in the decimal case are always
6816 -- copied from the parent base type.
6818 if Is_Decimal_Fixed_Point_Type (Parent_Type) then
6819 Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base));
6820 Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base));
6822 Set_Machine_Radix_10
6823 (Derived_Type, Machine_Radix_10 (Parent_Base));
6824 Set_Machine_Radix_10
6825 (Implicit_Base, Machine_Radix_10 (Parent_Base));
6827 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6829 if No_Constraint then
6830 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base));
6833 -- the analysis of the subtype_indication sets the
6834 -- digits value of the derived type.
6841 if Is_Integer_Type (Parent_Type) then
6842 Set_Has_Shift_Operator
6843 (Implicit_Base, Has_Shift_Operator (Parent_Type));
6846 -- The type of the bounds is that of the parent type, and they
6847 -- must be converted to the derived type.
6849 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
6851 -- The implicit_base should be frozen when the derived type is frozen,
6852 -- but note that it is used in the conversions of the bounds. For fixed
6853 -- types we delay the determination of the bounds until the proper
6854 -- freezing point. For other numeric types this is rejected by GCC, for
6855 -- reasons that are currently unclear (???), so we choose to freeze the
6856 -- implicit base now. In the case of integers and floating point types
6857 -- this is harmless because subsequent representation clauses cannot
6858 -- affect anything, but it is still baffling that we cannot use the
6859 -- same mechanism for all derived numeric types.
6861 -- There is a further complication: actually some representation
6862 -- clauses can affect the implicit base type. For example, attribute
6863 -- definition clauses for stream-oriented attributes need to set the
6864 -- corresponding TSS entries on the base type, and this normally
6865 -- cannot be done after the base type is frozen, so the circuitry in
6866 -- Sem_Ch13.New_Stream_Subprogram must account for this possibility
6867 -- and not use Set_TSS in this case.
6869 -- There are also consequences for the case of delayed representation
6870 -- aspects for some cases. For example, a Size aspect is delayed and
6871 -- should not be evaluated to the freeze point. This early freezing
6872 -- means that the size attribute evaluation happens too early???
6874 if Is_Fixed_Point_Type (Parent_Type) then
6875 Conditional_Delay (Implicit_Base, Parent_Type);
6877 Freeze_Before (N, Implicit_Base);
6879 end Build_Derived_Numeric_Type;
6881 --------------------------------
6882 -- Build_Derived_Private_Type --
6883 --------------------------------
6885 procedure Build_Derived_Private_Type
6887 Parent_Type : Entity_Id;
6888 Derived_Type : Entity_Id;
6889 Is_Completion : Boolean;
6890 Derive_Subps : Boolean := True)
6892 Loc : constant Source_Ptr := Sloc (N);
6893 Par_Base : constant Entity_Id := Base_Type (Parent_Type);
6894 Par_Scope : constant Entity_Id := Scope (Par_Base);
6895 Full_N : constant Node_Id := New_Copy_Tree (N);
6896 Full_Der : Entity_Id := New_Copy (Derived_Type);
6899 procedure Build_Full_Derivation;
6900 -- Build full derivation, i.e. derive from the full view
6902 procedure Copy_And_Build;
6903 -- Copy derived type declaration, replace parent with its full view,
6904 -- and build derivation
6906 ---------------------------
6907 -- Build_Full_Derivation --
6908 ---------------------------
6910 procedure Build_Full_Derivation is
6912 -- If parent scope is not open, install the declarations
6914 if not In_Open_Scopes (Par_Scope) then
6915 Install_Private_Declarations (Par_Scope);
6916 Install_Visible_Declarations (Par_Scope);
6918 Uninstall_Declarations (Par_Scope);
6920 -- If parent scope is open and in another unit, and parent has a
6921 -- completion, then the derivation is taking place in the visible
6922 -- part of a child unit. In that case retrieve the full view of
6923 -- the parent momentarily.
6925 elsif not In_Same_Source_Unit (N, Parent_Type) then
6926 Full_P := Full_View (Parent_Type);
6927 Exchange_Declarations (Parent_Type);
6929 Exchange_Declarations (Full_P);
6931 -- Otherwise it is a local derivation
6936 end Build_Full_Derivation;
6938 --------------------
6939 -- Copy_And_Build --
6940 --------------------
6942 procedure Copy_And_Build is
6943 Full_Parent : Entity_Id := Parent_Type;
6946 -- If the parent is itself derived from another private type,
6947 -- installing the private declarations has not affected its
6948 -- privacy status, so use its own full view explicitly.
6950 if Is_Private_Type (Full_Parent)
6951 and then Present (Full_View (Full_Parent))
6953 Full_Parent := Full_View (Full_Parent);
6956 -- And its underlying full view if necessary
6958 if Is_Private_Type (Full_Parent)
6959 and then Present (Underlying_Full_View (Full_Parent))
6961 Full_Parent := Underlying_Full_View (Full_Parent);
6964 -- For record, access and most enumeration types, derivation from
6965 -- the full view requires a fully-fledged declaration. In the other
6966 -- cases, just use an itype.
6968 if Ekind (Full_Parent) in Record_Kind
6969 or else Ekind (Full_Parent) in Access_Kind
6971 (Ekind (Full_Parent) in Enumeration_Kind
6972 and then not Is_Standard_Character_Type (Full_Parent)
6973 and then not Is_Generic_Type (Root_Type (Full_Parent)))
6975 -- Copy and adjust declaration to provide a completion for what
6976 -- is originally a private declaration. Indicate that full view
6977 -- is internally generated.
6979 Set_Comes_From_Source (Full_N, False);
6980 Set_Comes_From_Source (Full_Der, False);
6981 Set_Parent (Full_Der, Full_N);
6982 Set_Defining_Identifier (Full_N, Full_Der);
6984 -- If there are no constraints, adjust the subtype mark
6986 if Nkind (Subtype_Indication (Type_Definition (Full_N))) /=
6987 N_Subtype_Indication
6989 Set_Subtype_Indication
6990 (Type_Definition (Full_N),
6991 New_Occurrence_Of (Full_Parent, Sloc (Full_N)));
6994 Insert_After (N, Full_N);
6996 -- Build full view of derived type from full view of parent which
6997 -- is now installed. Subprograms have been derived on the partial
6998 -- view, the completion does not derive them anew.
7000 if Ekind (Full_Parent) in Record_Kind then
7002 -- If parent type is tagged, the completion inherits the proper
7003 -- primitive operations.
7005 if Is_Tagged_Type (Parent_Type) then
7006 Build_Derived_Record_Type
7007 (Full_N, Full_Parent, Full_Der, Derive_Subps);
7009 Build_Derived_Record_Type
7010 (Full_N, Full_Parent, Full_Der, Derive_Subps => False);
7015 (Full_N, Full_Parent, Full_Der,
7016 Is_Completion => False, Derive_Subps => False);
7019 -- The full declaration has been introduced into the tree and
7020 -- processed in the step above. It should not be analyzed again
7021 -- (when encountered later in the current list of declarations)
7022 -- to prevent spurious name conflicts. The full entity remains
7025 Set_Analyzed (Full_N);
7029 Make_Defining_Identifier (Sloc (Derived_Type),
7030 Chars => Chars (Derived_Type));
7031 Set_Is_Itype (Full_Der);
7032 Set_Associated_Node_For_Itype (Full_Der, N);
7033 Set_Parent (Full_Der, N);
7035 (N, Full_Parent, Full_Der,
7036 Is_Completion => False, Derive_Subps => False);
7039 Set_Has_Private_Declaration (Full_Der);
7040 Set_Has_Private_Declaration (Derived_Type);
7042 Set_Scope (Full_Der, Scope (Derived_Type));
7043 Set_Is_First_Subtype (Full_Der, Is_First_Subtype (Derived_Type));
7044 Set_Has_Size_Clause (Full_Der, False);
7045 Set_Has_Alignment_Clause (Full_Der, False);
7046 Set_Has_Delayed_Freeze (Full_Der);
7047 Set_Is_Frozen (Full_Der, False);
7048 Set_Freeze_Node (Full_Der, Empty);
7049 Set_Depends_On_Private (Full_Der, Has_Private_Component (Full_Der));
7050 Set_Is_Public (Full_Der, Is_Public (Derived_Type));
7052 -- The convention on the base type may be set in the private part
7053 -- and not propagated to the subtype until later, so we obtain the
7054 -- convention from the base type of the parent.
7056 Set_Convention (Full_Der, Convention (Base_Type (Full_Parent)));
7059 -- Start of processing for Build_Derived_Private_Type
7062 if Is_Tagged_Type (Parent_Type) then
7063 Full_P := Full_View (Parent_Type);
7065 -- A type extension of a type with unknown discriminants is an
7066 -- indefinite type that the back-end cannot handle directly.
7067 -- We treat it as a private type, and build a completion that is
7068 -- derived from the full view of the parent, and hopefully has
7069 -- known discriminants.
7071 -- If the full view of the parent type has an underlying record view,
7072 -- use it to generate the underlying record view of this derived type
7073 -- (required for chains of derivations with unknown discriminants).
7075 -- Minor optimization: we avoid the generation of useless underlying
7076 -- record view entities if the private type declaration has unknown
7077 -- discriminants but its corresponding full view has no
7080 if Has_Unknown_Discriminants (Parent_Type)
7081 and then Present (Full_P)
7082 and then (Has_Discriminants (Full_P)
7083 or else Present (Underlying_Record_View (Full_P)))
7084 and then not In_Open_Scopes (Par_Scope)
7085 and then Expander_Active
7088 Full_Der : constant Entity_Id := Make_Temporary (Loc, 'T');
7089 New_Ext : constant Node_Id :=
7091 (Record_Extension_Part (Type_Definition (N)));
7095 Build_Derived_Record_Type
7096 (N, Parent_Type, Derived_Type, Derive_Subps);
7098 -- Build anonymous completion, as a derivation from the full
7099 -- view of the parent. This is not a completion in the usual
7100 -- sense, because the current type is not private.
7103 Make_Full_Type_Declaration (Loc,
7104 Defining_Identifier => Full_Der,
7106 Make_Derived_Type_Definition (Loc,
7107 Subtype_Indication =>
7109 (Subtype_Indication (Type_Definition (N))),
7110 Record_Extension_Part => New_Ext));
7112 -- If the parent type has an underlying record view, use it
7113 -- here to build the new underlying record view.
7115 if Present (Underlying_Record_View (Full_P)) then
7117 (Nkind (Subtype_Indication (Type_Definition (Decl)))
7119 Set_Entity (Subtype_Indication (Type_Definition (Decl)),
7120 Underlying_Record_View (Full_P));
7123 Install_Private_Declarations (Par_Scope);
7124 Install_Visible_Declarations (Par_Scope);
7125 Insert_Before (N, Decl);
7127 -- Mark entity as an underlying record view before analysis,
7128 -- to avoid generating the list of its primitive operations
7129 -- (which is not really required for this entity) and thus
7130 -- prevent spurious errors associated with missing overriding
7131 -- of abstract primitives (overridden only for Derived_Type).
7133 Set_Ekind (Full_Der, E_Record_Type);
7134 Set_Is_Underlying_Record_View (Full_Der);
7135 Set_Default_SSO (Full_Der);
7139 pragma Assert (Has_Discriminants (Full_Der)
7140 and then not Has_Unknown_Discriminants (Full_Der));
7142 Uninstall_Declarations (Par_Scope);
7144 -- Freeze the underlying record view, to prevent generation of
7145 -- useless dispatching information, which is simply shared with
7146 -- the real derived type.
7148 Set_Is_Frozen (Full_Der);
7150 -- If the derived type has access discriminants, create
7151 -- references to their anonymous types now, to prevent
7152 -- back-end problems when their first use is in generated
7153 -- bodies of primitives.
7159 E := First_Entity (Full_Der);
7161 while Present (E) loop
7162 if Ekind (E) = E_Discriminant
7163 and then Ekind (Etype (E)) = E_Anonymous_Access_Type
7165 Build_Itype_Reference (Etype (E), Decl);
7172 -- Set up links between real entity and underlying record view
7174 Set_Underlying_Record_View (Derived_Type, Base_Type (Full_Der));
7175 Set_Underlying_Record_View (Base_Type (Full_Der), Derived_Type);
7178 -- If discriminants are known, build derived record
7181 Build_Derived_Record_Type
7182 (N, Parent_Type, Derived_Type, Derive_Subps);
7187 elsif Has_Discriminants (Parent_Type) then
7189 -- Build partial view of derived type from partial view of parent.
7190 -- This must be done before building the full derivation because the
7191 -- second derivation will modify the discriminants of the first and
7192 -- the discriminants are chained with the rest of the components in
7193 -- the full derivation.
7195 Build_Derived_Record_Type
7196 (N, Parent_Type, Derived_Type, Derive_Subps);
7198 -- Build the full derivation if this is not the anonymous derived
7199 -- base type created by Build_Derived_Record_Type in the constrained
7200 -- case (see point 5. of its head comment) since we build it for the
7201 -- derived subtype. And skip it for protected types altogether, as
7202 -- gigi does not use these types directly.
7204 if Present (Full_View (Parent_Type))
7205 and then not Is_Itype (Derived_Type)
7206 and then not (Ekind (Full_View (Parent_Type)) in Protected_Kind)
7209 Der_Base : constant Entity_Id := Base_Type (Derived_Type);
7211 Last_Discr : Entity_Id;
7214 -- If this is not a completion, construct the implicit full
7215 -- view by deriving from the full view of the parent type.
7216 -- But if this is a completion, the derived private type
7217 -- being built is a full view and the full derivation can
7218 -- only be its underlying full view.
7220 Build_Full_Derivation;
7222 if not Is_Completion then
7223 Set_Full_View (Derived_Type, Full_Der);
7225 Set_Underlying_Full_View (Derived_Type, Full_Der);
7228 if not Is_Base_Type (Derived_Type) then
7229 Set_Full_View (Der_Base, Base_Type (Full_Der));
7232 -- Copy the discriminant list from full view to the partial
7233 -- view (base type and its subtype). Gigi requires that the
7234 -- partial and full views have the same discriminants.
7236 -- Note that since the partial view points to discriminants
7237 -- in the full view, their scope will be that of the full
7238 -- view. This might cause some front end problems and need
7241 Discr := First_Discriminant (Base_Type (Full_Der));
7242 Set_First_Entity (Der_Base, Discr);
7245 Last_Discr := Discr;
7246 Next_Discriminant (Discr);
7247 exit when No (Discr);
7250 Set_Last_Entity (Der_Base, Last_Discr);
7251 Set_First_Entity (Derived_Type, First_Entity (Der_Base));
7252 Set_Last_Entity (Derived_Type, Last_Entity (Der_Base));
7254 Set_Stored_Constraint
7255 (Full_Der, Stored_Constraint (Derived_Type));
7259 elsif Present (Full_View (Parent_Type))
7260 and then Has_Discriminants (Full_View (Parent_Type))
7262 if Has_Unknown_Discriminants (Parent_Type)
7263 and then Nkind (Subtype_Indication (Type_Definition (N))) =
7264 N_Subtype_Indication
7267 ("cannot constrain type with unknown discriminants",
7268 Subtype_Indication (Type_Definition (N)));
7272 -- If this is not a completion, construct the implicit full view by
7273 -- deriving from the full view of the parent type. But if this is a
7274 -- completion, the derived private type being built is a full view
7275 -- and the full derivation can only be its underlying full view.
7277 Build_Full_Derivation;
7279 if not Is_Completion then
7280 Set_Full_View (Derived_Type, Full_Der);
7282 Set_Underlying_Full_View (Derived_Type, Full_Der);
7285 -- In any case, the primitive operations are inherited from the
7286 -- parent type, not from the internal full view.
7288 Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type));
7290 if Derive_Subps then
7291 Derive_Subprograms (Parent_Type, Derived_Type);
7294 Set_Stored_Constraint (Derived_Type, No_Elist);
7296 (Derived_Type, Is_Constrained (Full_View (Parent_Type)));
7299 -- Untagged type, No discriminants on either view
7301 if Nkind (Subtype_Indication (Type_Definition (N))) =
7302 N_Subtype_Indication
7305 ("illegal constraint on type without discriminants", N);
7308 if Present (Discriminant_Specifications (N))
7309 and then Present (Full_View (Parent_Type))
7310 and then not Is_Tagged_Type (Full_View (Parent_Type))
7312 Error_Msg_N ("cannot add discriminants to untagged type", N);
7315 Set_Stored_Constraint (Derived_Type, No_Elist);
7316 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
7317 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
7318 Set_Disable_Controlled (Derived_Type, Disable_Controlled
7320 Set_Has_Controlled_Component
7321 (Derived_Type, Has_Controlled_Component
7324 -- Direct controlled types do not inherit Finalize_Storage_Only flag
7326 if not Is_Controlled_Active (Parent_Type) then
7327 Set_Finalize_Storage_Only
7328 (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type));
7331 -- If this is not a completion, construct the implicit full view by
7332 -- deriving from the full view of the parent type.
7334 -- ??? If the parent is untagged private and its completion is
7335 -- tagged, this mechanism will not work because we cannot derive from
7336 -- the tagged full view unless we have an extension.
7338 if Present (Full_View (Parent_Type))
7339 and then not Is_Tagged_Type (Full_View (Parent_Type))
7340 and then not Is_Completion
7342 Build_Full_Derivation;
7343 Set_Full_View (Derived_Type, Full_Der);
7347 Set_Has_Unknown_Discriminants (Derived_Type,
7348 Has_Unknown_Discriminants (Parent_Type));
7350 if Is_Private_Type (Derived_Type) then
7351 Set_Private_Dependents (Derived_Type, New_Elmt_List);
7354 -- If the parent base type is in scope, add the derived type to its
7355 -- list of private dependents, because its full view may become
7356 -- visible subsequently (in a nested private part, a body, or in a
7357 -- further child unit).
7359 if Is_Private_Type (Par_Base) and then In_Open_Scopes (Par_Scope) then
7360 Append_Elmt (Derived_Type, Private_Dependents (Parent_Type));
7362 -- Check for unusual case where a type completed by a private
7363 -- derivation occurs within a package nested in a child unit, and
7364 -- the parent is declared in an ancestor.
7366 if Is_Child_Unit (Scope (Current_Scope))
7367 and then Is_Completion
7368 and then In_Private_Part (Current_Scope)
7369 and then Scope (Parent_Type) /= Current_Scope
7371 -- Note that if the parent has a completion in the private part,
7372 -- (which is itself a derivation from some other private type)
7373 -- it is that completion that is visible, there is no full view
7374 -- available, and no special processing is needed.
7376 and then Present (Full_View (Parent_Type))
7378 -- In this case, the full view of the parent type will become
7379 -- visible in the body of the enclosing child, and only then will
7380 -- the current type be possibly non-private. Build an underlying
7381 -- full view that will be installed when the enclosing child body
7384 if Present (Underlying_Full_View (Derived_Type)) then
7385 Full_Der := Underlying_Full_View (Derived_Type);
7387 Build_Full_Derivation;
7388 Set_Underlying_Full_View (Derived_Type, Full_Der);
7391 -- The full view will be used to swap entities on entry/exit to
7392 -- the body, and must appear in the entity list for the package.
7394 Append_Entity (Full_Der, Scope (Derived_Type));
7397 end Build_Derived_Private_Type;
7399 -------------------------------
7400 -- Build_Derived_Record_Type --
7401 -------------------------------
7405 -- Ideally we would like to use the same model of type derivation for
7406 -- tagged and untagged record types. Unfortunately this is not quite
7407 -- possible because the semantics of representation clauses is different
7408 -- for tagged and untagged records under inheritance. Consider the
7411 -- type R (...) is [tagged] record ... end record;
7412 -- type T (...) is new R (...) [with ...];
7414 -- The representation clauses for T can specify a completely different
7415 -- record layout from R's. Hence the same component can be placed in two
7416 -- very different positions in objects of type T and R. If R and T are
7417 -- tagged types, representation clauses for T can only specify the layout
7418 -- of non inherited components, thus components that are common in R and T
7419 -- have the same position in objects of type R and T.
7421 -- This has two implications. The first is that the entire tree for R's
7422 -- declaration needs to be copied for T in the untagged case, so that T
7423 -- can be viewed as a record type of its own with its own representation
7424 -- clauses. The second implication is the way we handle discriminants.
7425 -- Specifically, in the untagged case we need a way to communicate to Gigi
7426 -- what are the real discriminants in the record, while for the semantics
7427 -- we need to consider those introduced by the user to rename the
7428 -- discriminants in the parent type. This is handled by introducing the
7429 -- notion of stored discriminants. See below for more.
7431 -- Fortunately the way regular components are inherited can be handled in
7432 -- the same way in tagged and untagged types.
7434 -- To complicate things a bit more the private view of a private extension
7435 -- cannot be handled in the same way as the full view (for one thing the
7436 -- semantic rules are somewhat different). We will explain what differs
7439 -- 2. DISCRIMINANTS UNDER INHERITANCE
7441 -- The semantic rules governing the discriminants of derived types are
7444 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
7445 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
7447 -- If parent type has discriminants, then the discriminants that are
7448 -- declared in the derived type are [3.4 (11)]:
7450 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
7453 -- o Otherwise, each discriminant of the parent type (implicitly declared
7454 -- in the same order with the same specifications). In this case, the
7455 -- discriminants are said to be "inherited", or if unknown in the parent
7456 -- are also unknown in the derived type.
7458 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
7460 -- o The parent subtype must be constrained;
7462 -- o If the parent type is not a tagged type, then each discriminant of
7463 -- the derived type must be used in the constraint defining a parent
7464 -- subtype. [Implementation note: This ensures that the new discriminant
7465 -- can share storage with an existing discriminant.]
7467 -- For the derived type each discriminant of the parent type is either
7468 -- inherited, constrained to equal some new discriminant of the derived
7469 -- type, or constrained to the value of an expression.
7471 -- When inherited or constrained to equal some new discriminant, the
7472 -- parent discriminant and the discriminant of the derived type are said
7475 -- If a discriminant of the parent type is constrained to a specific value
7476 -- in the derived type definition, then the discriminant is said to be
7477 -- "specified" by that derived type definition.
7479 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES
7481 -- We have spoken about stored discriminants in point 1 (introduction)
7482 -- above. There are two sort of stored discriminants: implicit and
7483 -- explicit. As long as the derived type inherits the same discriminants as
7484 -- the root record type, stored discriminants are the same as regular
7485 -- discriminants, and are said to be implicit. However, if any discriminant
7486 -- in the root type was renamed in the derived type, then the derived
7487 -- type will contain explicit stored discriminants. Explicit stored
7488 -- discriminants are discriminants in addition to the semantically visible
7489 -- discriminants defined for the derived type. Stored discriminants are
7490 -- used by Gigi to figure out what are the physical discriminants in
7491 -- objects of the derived type (see precise definition in einfo.ads).
7492 -- As an example, consider the following:
7494 -- type R (D1, D2, D3 : Int) is record ... end record;
7495 -- type T1 is new R;
7496 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
7497 -- type T3 is new T2;
7498 -- type T4 (Y : Int) is new T3 (Y, 99);
7500 -- The following table summarizes the discriminants and stored
7501 -- discriminants in R and T1 through T4.
7503 -- Type Discrim Stored Discrim Comment
7504 -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R
7505 -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1
7506 -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2
7507 -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3
7508 -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4
7510 -- Field Corresponding_Discriminant (abbreviated CD below) allows us to
7511 -- find the corresponding discriminant in the parent type, while
7512 -- Original_Record_Component (abbreviated ORC below), the actual physical
7513 -- component that is renamed. Finally the field Is_Completely_Hidden
7514 -- (abbreviated ICH below) is set for all explicit stored discriminants
7515 -- (see einfo.ads for more info). For the above example this gives:
7517 -- Discrim CD ORC ICH
7518 -- ^^^^^^^ ^^ ^^^ ^^^
7519 -- D1 in R empty itself no
7520 -- D2 in R empty itself no
7521 -- D3 in R empty itself no
7523 -- D1 in T1 D1 in R itself no
7524 -- D2 in T1 D2 in R itself no
7525 -- D3 in T1 D3 in R itself no
7527 -- X1 in T2 D3 in T1 D3 in T2 no
7528 -- X2 in T2 D1 in T1 D1 in T2 no
7529 -- D1 in T2 empty itself yes
7530 -- D2 in T2 empty itself yes
7531 -- D3 in T2 empty itself yes
7533 -- X1 in T3 X1 in T2 D3 in T3 no
7534 -- X2 in T3 X2 in T2 D1 in T3 no
7535 -- D1 in T3 empty itself yes
7536 -- D2 in T3 empty itself yes
7537 -- D3 in T3 empty itself yes
7539 -- Y in T4 X1 in T3 D3 in T3 no
7540 -- D1 in T3 empty itself yes
7541 -- D2 in T3 empty itself yes
7542 -- D3 in T3 empty itself yes
7544 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES
7546 -- Type derivation for tagged types is fairly straightforward. If no
7547 -- discriminants are specified by the derived type, these are inherited
7548 -- from the parent. No explicit stored discriminants are ever necessary.
7549 -- The only manipulation that is done to the tree is that of adding a
7550 -- _parent field with parent type and constrained to the same constraint
7551 -- specified for the parent in the derived type definition. For instance:
7553 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
7554 -- type T1 is new R with null record;
7555 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
7557 -- are changed into:
7559 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
7560 -- _parent : R (D1, D2, D3);
7563 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
7564 -- _parent : T1 (X2, 88, X1);
7567 -- The discriminants actually present in R, T1 and T2 as well as their CD,
7568 -- ORC and ICH fields are:
7570 -- Discrim CD ORC ICH
7571 -- ^^^^^^^ ^^ ^^^ ^^^
7572 -- D1 in R empty itself no
7573 -- D2 in R empty itself no
7574 -- D3 in R empty itself no
7576 -- D1 in T1 D1 in R D1 in R no
7577 -- D2 in T1 D2 in R D2 in R no
7578 -- D3 in T1 D3 in R D3 in R no
7580 -- X1 in T2 D3 in T1 D3 in R no
7581 -- X2 in T2 D1 in T1 D1 in R no
7583 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS
7585 -- Regardless of whether we dealing with a tagged or untagged type
7586 -- we will transform all derived type declarations of the form
7588 -- type T is new R (...) [with ...];
7590 -- subtype S is R (...);
7591 -- type T is new S [with ...];
7593 -- type BT is new R [with ...];
7594 -- subtype T is BT (...);
7596 -- That is, the base derived type is constrained only if it has no
7597 -- discriminants. The reason for doing this is that GNAT's semantic model
7598 -- assumes that a base type with discriminants is unconstrained.
7600 -- Note that, strictly speaking, the above transformation is not always
7601 -- correct. Consider for instance the following excerpt from ACVC b34011a:
7603 -- procedure B34011A is
7604 -- type REC (D : integer := 0) is record
7609 -- type T6 is new Rec;
7610 -- function F return T6;
7615 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
7618 -- The definition of Q6.U is illegal. However transforming Q6.U into
7620 -- type BaseU is new T6;
7621 -- subtype U is BaseU (Q6.F.I)
7623 -- turns U into a legal subtype, which is incorrect. To avoid this problem
7624 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
7625 -- the transformation described above.
7627 -- There is another instance where the above transformation is incorrect.
7631 -- type Base (D : Integer) is tagged null record;
7632 -- procedure P (X : Base);
7634 -- type Der is new Base (2) with null record;
7635 -- procedure P (X : Der);
7638 -- Then the above transformation turns this into
7640 -- type Der_Base is new Base with null record;
7641 -- -- procedure P (X : Base) is implicitly inherited here
7642 -- -- as procedure P (X : Der_Base).
7644 -- subtype Der is Der_Base (2);
7645 -- procedure P (X : Der);
7646 -- -- The overriding of P (X : Der_Base) is illegal since we
7647 -- -- have a parameter conformance problem.
7649 -- To get around this problem, after having semantically processed Der_Base
7650 -- and the rewritten subtype declaration for Der, we copy Der_Base field
7651 -- Discriminant_Constraint from Der so that when parameter conformance is
7652 -- checked when P is overridden, no semantic errors are flagged.
7654 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS
7656 -- Regardless of whether we are dealing with a tagged or untagged type
7657 -- we will transform all derived type declarations of the form
7659 -- type R (D1, .., Dn : ...) is [tagged] record ...;
7660 -- type T is new R [with ...];
7662 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
7664 -- The reason for such transformation is that it allows us to implement a
7665 -- very clean form of component inheritance as explained below.
7667 -- Note that this transformation is not achieved by direct tree rewriting
7668 -- and manipulation, but rather by redoing the semantic actions that the
7669 -- above transformation will entail. This is done directly in routine
7670 -- Inherit_Components.
7672 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE
7674 -- In both tagged and untagged derived types, regular non discriminant
7675 -- components are inherited in the derived type from the parent type. In
7676 -- the absence of discriminants component, inheritance is straightforward
7677 -- as components can simply be copied from the parent.
7679 -- If the parent has discriminants, inheriting components constrained with
7680 -- these discriminants requires caution. Consider the following example:
7682 -- type R (D1, D2 : Positive) is [tagged] record
7683 -- S : String (D1 .. D2);
7686 -- type T1 is new R [with null record];
7687 -- type T2 (X : positive) is new R (1, X) [with null record];
7689 -- As explained in 6. above, T1 is rewritten as
7690 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
7691 -- which makes the treatment for T1 and T2 identical.
7693 -- What we want when inheriting S, is that references to D1 and D2 in R are
7694 -- replaced with references to their correct constraints, i.e. D1 and D2 in
7695 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
7696 -- with either discriminant references in the derived type or expressions.
7697 -- This replacement is achieved as follows: before inheriting R's
7698 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
7699 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
7700 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
7701 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
7702 -- by String (1 .. X).
7704 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS
7706 -- We explain here the rules governing private type extensions relevant to
7707 -- type derivation. These rules are explained on the following example:
7709 -- type D [(...)] is new A [(...)] with private; <-- partial view
7710 -- type D [(...)] is new P [(...)] with null record; <-- full view
7712 -- Type A is called the ancestor subtype of the private extension.
7713 -- Type P is the parent type of the full view of the private extension. It
7714 -- must be A or a type derived from A.
7716 -- The rules concerning the discriminants of private type extensions are
7719 -- o If a private extension inherits known discriminants from the ancestor
7720 -- subtype, then the full view must also inherit its discriminants from
7721 -- the ancestor subtype and the parent subtype of the full view must be
7722 -- constrained if and only if the ancestor subtype is constrained.
7724 -- o If a partial view has unknown discriminants, then the full view may
7725 -- define a definite or an indefinite subtype, with or without
7728 -- o If a partial view has neither known nor unknown discriminants, then
7729 -- the full view must define a definite subtype.
7731 -- o If the ancestor subtype of a private extension has constrained
7732 -- discriminants, then the parent subtype of the full view must impose a
7733 -- statically matching constraint on those discriminants.
7735 -- This means that only the following forms of private extensions are
7738 -- type D is new A with private; <-- partial view
7739 -- type D is new P with null record; <-- full view
7741 -- If A has no discriminants than P has no discriminants, otherwise P must
7742 -- inherit A's discriminants.
7744 -- type D is new A (...) with private; <-- partial view
7745 -- type D is new P (:::) with null record; <-- full view
7747 -- P must inherit A's discriminants and (...) and (:::) must statically
7750 -- subtype A is R (...);
7751 -- type D is new A with private; <-- partial view
7752 -- type D is new P with null record; <-- full view
7754 -- P must have inherited R's discriminants and must be derived from A or
7755 -- any of its subtypes.
7757 -- type D (..) is new A with private; <-- partial view
7758 -- type D (..) is new P [(:::)] with null record; <-- full view
7760 -- No specific constraints on P's discriminants or constraint (:::).
7761 -- Note that A can be unconstrained, but the parent subtype P must either
7762 -- be constrained or (:::) must be present.
7764 -- type D (..) is new A [(...)] with private; <-- partial view
7765 -- type D (..) is new P [(:::)] with null record; <-- full view
7767 -- P's constraints on A's discriminants must statically match those
7768 -- imposed by (...).
7770 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS
7772 -- The full view of a private extension is handled exactly as described
7773 -- above. The model chose for the private view of a private extension is
7774 -- the same for what concerns discriminants (i.e. they receive the same
7775 -- treatment as in the tagged case). However, the private view of the
7776 -- private extension always inherits the components of the parent base,
7777 -- without replacing any discriminant reference. Strictly speaking this is
7778 -- incorrect. However, Gigi never uses this view to generate code so this
7779 -- is a purely semantic issue. In theory, a set of transformations similar
7780 -- to those given in 5. and 6. above could be applied to private views of
7781 -- private extensions to have the same model of component inheritance as
7782 -- for non private extensions. However, this is not done because it would
7783 -- further complicate private type processing. Semantically speaking, this
7784 -- leaves us in an uncomfortable situation. As an example consider:
7787 -- type R (D : integer) is tagged record
7788 -- S : String (1 .. D);
7790 -- procedure P (X : R);
7791 -- type T is new R (1) with private;
7793 -- type T is new R (1) with null record;
7796 -- This is transformed into:
7799 -- type R (D : integer) is tagged record
7800 -- S : String (1 .. D);
7802 -- procedure P (X : R);
7803 -- type T is new R (1) with private;
7805 -- type BaseT is new R with null record;
7806 -- subtype T is BaseT (1);
7809 -- (strictly speaking the above is incorrect Ada)
7811 -- From the semantic standpoint the private view of private extension T
7812 -- should be flagged as constrained since one can clearly have
7816 -- in a unit withing Pack. However, when deriving subprograms for the
7817 -- private view of private extension T, T must be seen as unconstrained
7818 -- since T has discriminants (this is a constraint of the current
7819 -- subprogram derivation model). Thus, when processing the private view of
7820 -- a private extension such as T, we first mark T as unconstrained, we
7821 -- process it, we perform program derivation and just before returning from
7822 -- Build_Derived_Record_Type we mark T as constrained.
7824 -- ??? Are there are other uncomfortable cases that we will have to
7827 -- 10. RECORD_TYPE_WITH_PRIVATE complications
7829 -- Types that are derived from a visible record type and have a private
7830 -- extension present other peculiarities. They behave mostly like private
7831 -- types, but if they have primitive operations defined, these will not
7832 -- have the proper signatures for further inheritance, because other
7833 -- primitive operations will use the implicit base that we define for
7834 -- private derivations below. This affect subprogram inheritance (see
7835 -- Derive_Subprograms for details). We also derive the implicit base from
7836 -- the base type of the full view, so that the implicit base is a record
7837 -- type and not another private type, This avoids infinite loops.
7839 procedure Build_Derived_Record_Type
7841 Parent_Type : Entity_Id;
7842 Derived_Type : Entity_Id;
7843 Derive_Subps : Boolean := True)
7845 Discriminant_Specs : constant Boolean :=
7846 Present (Discriminant_Specifications (N));
7847 Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type);
7848 Loc : constant Source_Ptr := Sloc (N);
7849 Private_Extension : constant Boolean :=
7850 Nkind (N) = N_Private_Extension_Declaration;
7851 Assoc_List : Elist_Id;
7852 Constraint_Present : Boolean;
7854 Discrim : Entity_Id;
7856 Inherit_Discrims : Boolean := False;
7857 Last_Discrim : Entity_Id;
7858 New_Base : Entity_Id;
7860 New_Discrs : Elist_Id;
7861 New_Indic : Node_Id;
7862 Parent_Base : Entity_Id;
7863 Save_Etype : Entity_Id;
7864 Save_Discr_Constr : Elist_Id;
7865 Save_Next_Entity : Entity_Id;
7868 Discs : Elist_Id := New_Elmt_List;
7869 -- An empty Discs list means that there were no constraints in the
7870 -- subtype indication or that there was an error processing it.
7873 if Ekind (Parent_Type) = E_Record_Type_With_Private
7874 and then Present (Full_View (Parent_Type))
7875 and then Has_Discriminants (Parent_Type)
7877 Parent_Base := Base_Type (Full_View (Parent_Type));
7879 Parent_Base := Base_Type (Parent_Type);
7882 -- AI05-0115 : if this is a derivation from a private type in some
7883 -- other scope that may lead to invisible components for the derived
7884 -- type, mark it accordingly.
7886 if Is_Private_Type (Parent_Type) then
7887 if Scope (Parent_Type) = Scope (Derived_Type) then
7890 elsif In_Open_Scopes (Scope (Parent_Type))
7891 and then In_Private_Part (Scope (Parent_Type))
7896 Set_Has_Private_Ancestor (Derived_Type);
7900 Set_Has_Private_Ancestor
7901 (Derived_Type, Has_Private_Ancestor (Parent_Type));
7904 -- Before we start the previously documented transformations, here is
7905 -- little fix for size and alignment of tagged types. Normally when we
7906 -- derive type D from type P, we copy the size and alignment of P as the
7907 -- default for D, and in the absence of explicit representation clauses
7908 -- for D, the size and alignment are indeed the same as the parent.
7910 -- But this is wrong for tagged types, since fields may be added, and
7911 -- the default size may need to be larger, and the default alignment may
7912 -- need to be larger.
7914 -- We therefore reset the size and alignment fields in the tagged case.
7915 -- Note that the size and alignment will in any case be at least as
7916 -- large as the parent type (since the derived type has a copy of the
7917 -- parent type in the _parent field)
7919 -- The type is also marked as being tagged here, which is needed when
7920 -- processing components with a self-referential anonymous access type
7921 -- in the call to Check_Anonymous_Access_Components below. Note that
7922 -- this flag is also set later on for completeness.
7925 Set_Is_Tagged_Type (Derived_Type);
7926 Init_Size_Align (Derived_Type);
7929 -- STEP 0a: figure out what kind of derived type declaration we have
7931 if Private_Extension then
7933 Set_Ekind (Derived_Type, E_Record_Type_With_Private);
7934 Set_Default_SSO (Derived_Type);
7937 Type_Def := Type_Definition (N);
7939 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
7940 -- Parent_Base can be a private type or private extension. However,
7941 -- for tagged types with an extension the newly added fields are
7942 -- visible and hence the Derived_Type is always an E_Record_Type.
7943 -- (except that the parent may have its own private fields).
7944 -- For untagged types we preserve the Ekind of the Parent_Base.
7946 if Present (Record_Extension_Part (Type_Def)) then
7947 Set_Ekind (Derived_Type, E_Record_Type);
7948 Set_Default_SSO (Derived_Type);
7950 -- Create internal access types for components with anonymous
7953 if Ada_Version >= Ada_2005 then
7954 Check_Anonymous_Access_Components
7955 (N, Derived_Type, Derived_Type,
7956 Component_List (Record_Extension_Part (Type_Def)));
7960 Set_Ekind (Derived_Type, Ekind (Parent_Base));
7964 -- Indic can either be an N_Identifier if the subtype indication
7965 -- contains no constraint or an N_Subtype_Indication if the subtype
7966 -- indication has a constraint.
7968 Indic := Subtype_Indication (Type_Def);
7969 Constraint_Present := (Nkind (Indic) = N_Subtype_Indication);
7971 -- Check that the type has visible discriminants. The type may be
7972 -- a private type with unknown discriminants whose full view has
7973 -- discriminants which are invisible.
7975 if Constraint_Present then
7976 if not Has_Discriminants (Parent_Base)
7978 (Has_Unknown_Discriminants (Parent_Base)
7979 and then Is_Private_Type (Parent_Base))
7982 ("invalid constraint: type has no discriminant",
7983 Constraint (Indic));
7985 Constraint_Present := False;
7986 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7988 elsif Is_Constrained (Parent_Type) then
7990 ("invalid constraint: parent type is already constrained",
7991 Constraint (Indic));
7993 Constraint_Present := False;
7994 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7998 -- STEP 0b: If needed, apply transformation given in point 5. above
8000 if not Private_Extension
8001 and then Has_Discriminants (Parent_Type)
8002 and then not Discriminant_Specs
8003 and then (Is_Constrained (Parent_Type) or else Constraint_Present)
8005 -- First, we must analyze the constraint (see comment in point 5.)
8006 -- The constraint may come from the subtype indication of the full
8009 if Constraint_Present then
8010 New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic);
8012 -- If there is no explicit constraint, there might be one that is
8013 -- inherited from a constrained parent type. In that case verify that
8014 -- it conforms to the constraint in the partial view. In perverse
8015 -- cases the parent subtypes of the partial and full view can have
8016 -- different constraints.
8018 elsif Present (Stored_Constraint (Parent_Type)) then
8019 New_Discrs := Stored_Constraint (Parent_Type);
8022 New_Discrs := No_Elist;
8025 if Has_Discriminants (Derived_Type)
8026 and then Has_Private_Declaration (Derived_Type)
8027 and then Present (Discriminant_Constraint (Derived_Type))
8028 and then Present (New_Discrs)
8030 -- Verify that constraints of the full view statically match
8031 -- those given in the partial view.
8037 C1 := First_Elmt (New_Discrs);
8038 C2 := First_Elmt (Discriminant_Constraint (Derived_Type));
8039 while Present (C1) and then Present (C2) loop
8040 if Fully_Conformant_Expressions (Node (C1), Node (C2))
8042 (Is_OK_Static_Expression (Node (C1))
8043 and then Is_OK_Static_Expression (Node (C2))
8045 Expr_Value (Node (C1)) = Expr_Value (Node (C2)))
8050 if Constraint_Present then
8052 ("constraint not conformant to previous declaration",
8056 ("constraint of full view is incompatible "
8057 & "with partial view", N);
8067 -- Insert and analyze the declaration for the unconstrained base type
8069 New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B');
8072 Make_Full_Type_Declaration (Loc,
8073 Defining_Identifier => New_Base,
8075 Make_Derived_Type_Definition (Loc,
8076 Abstract_Present => Abstract_Present (Type_Def),
8077 Limited_Present => Limited_Present (Type_Def),
8078 Subtype_Indication =>
8079 New_Occurrence_Of (Parent_Base, Loc),
8080 Record_Extension_Part =>
8081 Relocate_Node (Record_Extension_Part (Type_Def)),
8082 Interface_List => Interface_List (Type_Def)));
8084 Set_Parent (New_Decl, Parent (N));
8085 Mark_Rewrite_Insertion (New_Decl);
8086 Insert_Before (N, New_Decl);
8088 -- In the extension case, make sure ancestor is frozen appropriately
8089 -- (see also non-discriminated case below).
8091 if Present (Record_Extension_Part (Type_Def))
8092 or else Is_Interface (Parent_Base)
8094 Freeze_Before (New_Decl, Parent_Type);
8097 -- Note that this call passes False for the Derive_Subps parameter
8098 -- because subprogram derivation is deferred until after creating
8099 -- the subtype (see below).
8102 (New_Decl, Parent_Base, New_Base,
8103 Is_Completion => False, Derive_Subps => False);
8105 -- ??? This needs re-examination to determine whether the
8106 -- above call can simply be replaced by a call to Analyze.
8108 Set_Analyzed (New_Decl);
8110 -- Insert and analyze the declaration for the constrained subtype
8112 if Constraint_Present then
8114 Make_Subtype_Indication (Loc,
8115 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8116 Constraint => Relocate_Node (Constraint (Indic)));
8120 Constr_List : constant List_Id := New_List;
8125 C := First_Elmt (Discriminant_Constraint (Parent_Type));
8126 while Present (C) loop
8129 -- It is safe here to call New_Copy_Tree since we called
8130 -- Force_Evaluation on each constraint previously
8131 -- in Build_Discriminant_Constraints.
8133 Append (New_Copy_Tree (Expr), To => Constr_List);
8139 Make_Subtype_Indication (Loc,
8140 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8142 Make_Index_Or_Discriminant_Constraint (Loc, Constr_List));
8147 Make_Subtype_Declaration (Loc,
8148 Defining_Identifier => Derived_Type,
8149 Subtype_Indication => New_Indic));
8153 -- Derivation of subprograms must be delayed until the full subtype
8154 -- has been established, to ensure proper overriding of subprograms
8155 -- inherited by full types. If the derivations occurred as part of
8156 -- the call to Build_Derived_Type above, then the check for type
8157 -- conformance would fail because earlier primitive subprograms
8158 -- could still refer to the full type prior the change to the new
8159 -- subtype and hence would not match the new base type created here.
8160 -- Subprograms are not derived, however, when Derive_Subps is False
8161 -- (since otherwise there could be redundant derivations).
8163 if Derive_Subps then
8164 Derive_Subprograms (Parent_Type, Derived_Type);
8167 -- For tagged types the Discriminant_Constraint of the new base itype
8168 -- is inherited from the first subtype so that no subtype conformance
8169 -- problem arise when the first subtype overrides primitive
8170 -- operations inherited by the implicit base type.
8173 Set_Discriminant_Constraint
8174 (New_Base, Discriminant_Constraint (Derived_Type));
8180 -- If we get here Derived_Type will have no discriminants or it will be
8181 -- a discriminated unconstrained base type.
8183 -- STEP 1a: perform preliminary actions/checks for derived tagged types
8187 -- The parent type is frozen for non-private extensions (RM 13.14(7))
8188 -- The declaration of a specific descendant of an interface type
8189 -- freezes the interface type (RM 13.14).
8191 if not Private_Extension or else Is_Interface (Parent_Base) then
8192 Freeze_Before (N, Parent_Type);
8195 -- In Ada 2005 (AI-344), the restriction that a derived tagged type
8196 -- cannot be declared at a deeper level than its parent type is
8197 -- removed. The check on derivation within a generic body is also
8198 -- relaxed, but there's a restriction that a derived tagged type
8199 -- cannot be declared in a generic body if it's derived directly
8200 -- or indirectly from a formal type of that generic.
8202 if Ada_Version >= Ada_2005 then
8203 if Present (Enclosing_Generic_Body (Derived_Type)) then
8205 Ancestor_Type : Entity_Id;
8208 -- Check to see if any ancestor of the derived type is a
8211 Ancestor_Type := Parent_Type;
8212 while not Is_Generic_Type (Ancestor_Type)
8213 and then Etype (Ancestor_Type) /= Ancestor_Type
8215 Ancestor_Type := Etype (Ancestor_Type);
8218 -- If the derived type does have a formal type as an
8219 -- ancestor, then it's an error if the derived type is
8220 -- declared within the body of the generic unit that
8221 -- declares the formal type in its generic formal part. It's
8222 -- sufficient to check whether the ancestor type is declared
8223 -- inside the same generic body as the derived type (such as
8224 -- within a nested generic spec), in which case the
8225 -- derivation is legal. If the formal type is declared
8226 -- outside of that generic body, then it's guaranteed that
8227 -- the derived type is declared within the generic body of
8228 -- the generic unit declaring the formal type.
8230 if Is_Generic_Type (Ancestor_Type)
8231 and then Enclosing_Generic_Body (Ancestor_Type) /=
8232 Enclosing_Generic_Body (Derived_Type)
8235 ("parent type of& must not be descendant of formal type"
8236 & " of an enclosing generic body",
8237 Indic, Derived_Type);
8242 elsif Type_Access_Level (Derived_Type) /=
8243 Type_Access_Level (Parent_Type)
8244 and then not Is_Generic_Type (Derived_Type)
8246 if Is_Controlled (Parent_Type) then
8248 ("controlled type must be declared at the library level",
8252 ("type extension at deeper accessibility level than parent",
8258 GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type);
8261 and then GB /= Enclosing_Generic_Body (Parent_Base)
8264 ("parent type of& must not be outside generic body"
8266 Indic, Derived_Type);
8272 -- Ada 2005 (AI-251)
8274 if Ada_Version >= Ada_2005 and then Is_Tagged then
8276 -- "The declaration of a specific descendant of an interface type
8277 -- freezes the interface type" (RM 13.14).
8282 if Is_Non_Empty_List (Interface_List (Type_Def)) then
8283 Iface := First (Interface_List (Type_Def));
8284 while Present (Iface) loop
8285 Freeze_Before (N, Etype (Iface));
8292 -- STEP 1b : preliminary cleanup of the full view of private types
8294 -- If the type is already marked as having discriminants, then it's the
8295 -- completion of a private type or private extension and we need to
8296 -- retain the discriminants from the partial view if the current
8297 -- declaration has Discriminant_Specifications so that we can verify
8298 -- conformance. However, we must remove any existing components that
8299 -- were inherited from the parent (and attached in Copy_And_Swap)
8300 -- because the full type inherits all appropriate components anyway, and
8301 -- we do not want the partial view's components interfering.
8303 if Has_Discriminants (Derived_Type) and then Discriminant_Specs then
8304 Discrim := First_Discriminant (Derived_Type);
8306 Last_Discrim := Discrim;
8307 Next_Discriminant (Discrim);
8308 exit when No (Discrim);
8311 Set_Last_Entity (Derived_Type, Last_Discrim);
8313 -- In all other cases wipe out the list of inherited components (even
8314 -- inherited discriminants), it will be properly rebuilt here.
8317 Set_First_Entity (Derived_Type, Empty);
8318 Set_Last_Entity (Derived_Type, Empty);
8321 -- STEP 1c: Initialize some flags for the Derived_Type
8323 -- The following flags must be initialized here so that
8324 -- Process_Discriminants can check that discriminants of tagged types do
8325 -- not have a default initial value and that access discriminants are
8326 -- only specified for limited records. For completeness, these flags are
8327 -- also initialized along with all the other flags below.
8329 -- AI-419: Limitedness is not inherited from an interface parent, so to
8330 -- be limited in that case the type must be explicitly declared as
8331 -- limited. However, task and protected interfaces are always limited.
8333 if Limited_Present (Type_Def) then
8334 Set_Is_Limited_Record (Derived_Type);
8336 elsif Is_Limited_Record (Parent_Type)
8337 or else (Present (Full_View (Parent_Type))
8338 and then Is_Limited_Record (Full_View (Parent_Type)))
8340 if not Is_Interface (Parent_Type)
8341 or else Is_Synchronized_Interface (Parent_Type)
8342 or else Is_Protected_Interface (Parent_Type)
8343 or else Is_Task_Interface (Parent_Type)
8345 Set_Is_Limited_Record (Derived_Type);
8349 -- STEP 2a: process discriminants of derived type if any
8351 Push_Scope (Derived_Type);
8353 if Discriminant_Specs then
8354 Set_Has_Unknown_Discriminants (Derived_Type, False);
8356 -- The following call initializes fields Has_Discriminants and
8357 -- Discriminant_Constraint, unless we are processing the completion
8358 -- of a private type declaration.
8360 Check_Or_Process_Discriminants (N, Derived_Type);
8362 -- For untagged types, the constraint on the Parent_Type must be
8363 -- present and is used to rename the discriminants.
8365 if not Is_Tagged and then not Has_Discriminants (Parent_Type) then
8366 Error_Msg_N ("untagged parent must have discriminants", Indic);
8368 elsif not Is_Tagged and then not Constraint_Present then
8370 ("discriminant constraint needed for derived untagged records",
8373 -- Otherwise the parent subtype must be constrained unless we have a
8374 -- private extension.
8376 elsif not Constraint_Present
8377 and then not Private_Extension
8378 and then not Is_Constrained (Parent_Type)
8381 ("unconstrained type not allowed in this context", Indic);
8383 elsif Constraint_Present then
8384 -- The following call sets the field Corresponding_Discriminant
8385 -- for the discriminants in the Derived_Type.
8387 Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True);
8389 -- For untagged types all new discriminants must rename
8390 -- discriminants in the parent. For private extensions new
8391 -- discriminants cannot rename old ones (implied by [7.3(13)]).
8393 Discrim := First_Discriminant (Derived_Type);
8394 while Present (Discrim) loop
8396 and then No (Corresponding_Discriminant (Discrim))
8399 ("new discriminants must constrain old ones", Discrim);
8401 elsif Private_Extension
8402 and then Present (Corresponding_Discriminant (Discrim))
8405 ("only static constraints allowed for parent"
8406 & " discriminants in the partial view", Indic);
8410 -- If a new discriminant is used in the constraint, then its
8411 -- subtype must be statically compatible with the parent
8412 -- discriminant's subtype (3.7(15)).
8414 -- However, if the record contains an array constrained by
8415 -- the discriminant but with some different bound, the compiler
8416 -- attemps to create a smaller range for the discriminant type.
8417 -- (See exp_ch3.Adjust_Discriminants). In this case, where
8418 -- the discriminant type is a scalar type, the check must use
8419 -- the original discriminant type in the parent declaration.
8422 Corr_Disc : constant Entity_Id :=
8423 Corresponding_Discriminant (Discrim);
8424 Disc_Type : constant Entity_Id := Etype (Discrim);
8425 Corr_Type : Entity_Id;
8428 if Present (Corr_Disc) then
8429 if Is_Scalar_Type (Disc_Type) then
8431 Entity (Discriminant_Type (Parent (Corr_Disc)));
8433 Corr_Type := Etype (Corr_Disc);
8437 Subtypes_Statically_Compatible (Disc_Type, Corr_Type)
8440 ("subtype must be compatible "
8441 & "with parent discriminant",
8447 Next_Discriminant (Discrim);
8450 -- Check whether the constraints of the full view statically
8451 -- match those imposed by the parent subtype [7.3(13)].
8453 if Present (Stored_Constraint (Derived_Type)) then
8458 C1 := First_Elmt (Discs);
8459 C2 := First_Elmt (Stored_Constraint (Derived_Type));
8460 while Present (C1) and then Present (C2) loop
8462 Fully_Conformant_Expressions (Node (C1), Node (C2))
8465 ("not conformant with previous declaration",
8476 -- STEP 2b: No new discriminants, inherit discriminants if any
8479 if Private_Extension then
8480 Set_Has_Unknown_Discriminants
8482 Has_Unknown_Discriminants (Parent_Type)
8483 or else Unknown_Discriminants_Present (N));
8485 -- The partial view of the parent may have unknown discriminants,
8486 -- but if the full view has discriminants and the parent type is
8487 -- in scope they must be inherited.
8489 elsif Has_Unknown_Discriminants (Parent_Type)
8491 (not Has_Discriminants (Parent_Type)
8492 or else not In_Open_Scopes (Scope (Parent_Type)))
8494 Set_Has_Unknown_Discriminants (Derived_Type);
8497 if not Has_Unknown_Discriminants (Derived_Type)
8498 and then not Has_Unknown_Discriminants (Parent_Base)
8499 and then Has_Discriminants (Parent_Type)
8501 Inherit_Discrims := True;
8502 Set_Has_Discriminants
8503 (Derived_Type, True);
8504 Set_Discriminant_Constraint
8505 (Derived_Type, Discriminant_Constraint (Parent_Base));
8508 -- The following test is true for private types (remember
8509 -- transformation 5. is not applied to those) and in an error
8512 if Constraint_Present then
8513 Discs := Build_Discriminant_Constraints (Parent_Type, Indic);
8516 -- For now mark a new derived type as constrained only if it has no
8517 -- discriminants. At the end of Build_Derived_Record_Type we properly
8518 -- set this flag in the case of private extensions. See comments in
8519 -- point 9. just before body of Build_Derived_Record_Type.
8523 not (Inherit_Discrims
8524 or else Has_Unknown_Discriminants (Derived_Type)));
8527 -- STEP 3: initialize fields of derived type
8529 Set_Is_Tagged_Type (Derived_Type, Is_Tagged);
8530 Set_Stored_Constraint (Derived_Type, No_Elist);
8532 -- Ada 2005 (AI-251): Private type-declarations can implement interfaces
8533 -- but cannot be interfaces
8535 if not Private_Extension
8536 and then Ekind (Derived_Type) /= E_Private_Type
8537 and then Ekind (Derived_Type) /= E_Limited_Private_Type
8539 if Interface_Present (Type_Def) then
8540 Analyze_Interface_Declaration (Derived_Type, Type_Def);
8543 Set_Interfaces (Derived_Type, No_Elist);
8546 -- Fields inherited from the Parent_Type
8548 Set_Has_Specified_Layout
8549 (Derived_Type, Has_Specified_Layout (Parent_Type));
8550 Set_Is_Limited_Composite
8551 (Derived_Type, Is_Limited_Composite (Parent_Type));
8552 Set_Is_Private_Composite
8553 (Derived_Type, Is_Private_Composite (Parent_Type));
8555 if Is_Tagged_Type (Parent_Type) then
8556 Set_No_Tagged_Streams_Pragma
8557 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
8560 -- Fields inherited from the Parent_Base
8562 Set_Has_Controlled_Component
8563 (Derived_Type, Has_Controlled_Component (Parent_Base));
8564 Set_Has_Non_Standard_Rep
8565 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8566 Set_Has_Primitive_Operations
8567 (Derived_Type, Has_Primitive_Operations (Parent_Base));
8569 -- Fields inherited from the Parent_Base in the non-private case
8571 if Ekind (Derived_Type) = E_Record_Type then
8572 Set_Has_Complex_Representation
8573 (Derived_Type, Has_Complex_Representation (Parent_Base));
8576 -- Fields inherited from the Parent_Base for record types
8578 if Is_Record_Type (Derived_Type) then
8580 Parent_Full : Entity_Id;
8583 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
8584 -- Parent_Base can be a private type or private extension. Go
8585 -- to the full view here to get the E_Record_Type specific flags.
8587 if Present (Full_View (Parent_Base)) then
8588 Parent_Full := Full_View (Parent_Base);
8590 Parent_Full := Parent_Base;
8593 Set_OK_To_Reorder_Components
8594 (Derived_Type, OK_To_Reorder_Components (Parent_Full));
8598 -- Set fields for private derived types
8600 if Is_Private_Type (Derived_Type) then
8601 Set_Depends_On_Private (Derived_Type, True);
8602 Set_Private_Dependents (Derived_Type, New_Elmt_List);
8604 -- Inherit fields from non private record types. If this is the
8605 -- completion of a derivation from a private type, the parent itself
8606 -- is private, and the attributes come from its full view, which must
8610 if Is_Private_Type (Parent_Base)
8611 and then not Is_Record_Type (Parent_Base)
8613 Set_Component_Alignment
8614 (Derived_Type, Component_Alignment (Full_View (Parent_Base)));
8616 (Derived_Type, C_Pass_By_Copy (Full_View (Parent_Base)));
8618 Set_Component_Alignment
8619 (Derived_Type, Component_Alignment (Parent_Base));
8621 (Derived_Type, C_Pass_By_Copy (Parent_Base));
8625 -- Set fields for tagged types
8628 Set_Direct_Primitive_Operations (Derived_Type, New_Elmt_List);
8630 -- All tagged types defined in Ada.Finalization are controlled
8632 if Chars (Scope (Derived_Type)) = Name_Finalization
8633 and then Chars (Scope (Scope (Derived_Type))) = Name_Ada
8634 and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard
8636 Set_Is_Controlled (Derived_Type);
8638 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Base));
8641 -- Minor optimization: there is no need to generate the class-wide
8642 -- entity associated with an underlying record view.
8644 if not Is_Underlying_Record_View (Derived_Type) then
8645 Make_Class_Wide_Type (Derived_Type);
8648 Set_Is_Abstract_Type (Derived_Type, Abstract_Present (Type_Def));
8650 if Has_Discriminants (Derived_Type)
8651 and then Constraint_Present
8653 Set_Stored_Constraint
8654 (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs));
8657 if Ada_Version >= Ada_2005 then
8659 Ifaces_List : Elist_Id;
8662 -- Checks rules 3.9.4 (13/2 and 14/2)
8664 if Comes_From_Source (Derived_Type)
8665 and then not Is_Private_Type (Derived_Type)
8666 and then Is_Interface (Parent_Type)
8667 and then not Is_Interface (Derived_Type)
8669 if Is_Task_Interface (Parent_Type) then
8671 ("(Ada 2005) task type required (RM 3.9.4 (13.2))",
8674 elsif Is_Protected_Interface (Parent_Type) then
8676 ("(Ada 2005) protected type required (RM 3.9.4 (14.2))",
8681 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
8683 Check_Interfaces (N, Type_Def);
8685 -- Ada 2005 (AI-251): Collect the list of progenitors that are
8686 -- not already in the parents.
8690 Ifaces_List => Ifaces_List,
8691 Exclude_Parents => True);
8693 Set_Interfaces (Derived_Type, Ifaces_List);
8695 -- If the derived type is the anonymous type created for
8696 -- a declaration whose parent has a constraint, propagate
8697 -- the interface list to the source type. This must be done
8698 -- prior to the completion of the analysis of the source type
8699 -- because the components in the extension may contain current
8700 -- instances whose legality depends on some ancestor.
8702 if Is_Itype (Derived_Type) then
8704 Def : constant Node_Id :=
8705 Associated_Node_For_Itype (Derived_Type);
8708 and then Nkind (Def) = N_Full_Type_Declaration
8711 (Defining_Identifier (Def), Ifaces_List);
8716 -- Propagate inherited invariant information of parents
8719 if Ada_Version >= Ada_2012
8720 and then not Is_Interface (Derived_Type)
8722 if Has_Inheritable_Invariants (Parent_Type) then
8723 Set_Has_Invariants (Derived_Type);
8724 Set_Has_Inheritable_Invariants (Derived_Type);
8726 elsif not Is_Empty_Elmt_List (Ifaces_List) then
8731 AI := First_Elmt (Ifaces_List);
8732 while Present (AI) loop
8733 if Has_Inheritable_Invariants (Node (AI)) then
8734 Set_Has_Invariants (Derived_Type);
8735 Set_Has_Inheritable_Invariants (Derived_Type);
8746 -- A type extension is automatically Ghost when one of its
8747 -- progenitors is Ghost (SPARK RM 6.9(9)). This property is
8748 -- also inherited when the parent type is Ghost, but this is
8749 -- done in Build_Derived_Type as the mechanism also handles
8750 -- untagged derivations.
8752 if Implements_Ghost_Interface (Derived_Type) then
8753 Set_Is_Ghost_Entity (Derived_Type);
8759 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Base));
8760 Set_Has_Non_Standard_Rep
8761 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8764 -- STEP 4: Inherit components from the parent base and constrain them.
8765 -- Apply the second transformation described in point 6. above.
8767 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
8768 or else not Has_Discriminants (Parent_Type)
8769 or else not Is_Constrained (Parent_Type)
8773 Constrs := Discriminant_Constraint (Parent_Type);
8778 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
8780 -- STEP 5a: Copy the parent record declaration for untagged types
8782 if not Is_Tagged then
8784 -- Discriminant_Constraint (Derived_Type) has been properly
8785 -- constructed. Save it and temporarily set it to Empty because we
8786 -- do not want the call to New_Copy_Tree below to mess this list.
8788 if Has_Discriminants (Derived_Type) then
8789 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
8790 Set_Discriminant_Constraint (Derived_Type, No_Elist);
8792 Save_Discr_Constr := No_Elist;
8795 -- Save the Etype field of Derived_Type. It is correctly set now,
8796 -- but the call to New_Copy tree may remap it to point to itself,
8797 -- which is not what we want. Ditto for the Next_Entity field.
8799 Save_Etype := Etype (Derived_Type);
8800 Save_Next_Entity := Next_Entity (Derived_Type);
8802 -- Assoc_List maps all stored discriminants in the Parent_Base to
8803 -- stored discriminants in the Derived_Type. It is fundamental that
8804 -- no types or itypes with discriminants other than the stored
8805 -- discriminants appear in the entities declared inside
8806 -- Derived_Type, since the back end cannot deal with it.
8810 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
8812 -- Restore the fields saved prior to the New_Copy_Tree call
8813 -- and compute the stored constraint.
8815 Set_Etype (Derived_Type, Save_Etype);
8816 Set_Next_Entity (Derived_Type, Save_Next_Entity);
8818 if Has_Discriminants (Derived_Type) then
8819 Set_Discriminant_Constraint
8820 (Derived_Type, Save_Discr_Constr);
8821 Set_Stored_Constraint
8822 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
8823 Replace_Components (Derived_Type, New_Decl);
8824 Set_Has_Implicit_Dereference
8825 (Derived_Type, Has_Implicit_Dereference (Parent_Type));
8828 -- Insert the new derived type declaration
8830 Rewrite (N, New_Decl);
8832 -- STEP 5b: Complete the processing for record extensions in generics
8834 -- There is no completion for record extensions declared in the
8835 -- parameter part of a generic, so we need to complete processing for
8836 -- these generic record extensions here. The Record_Type_Definition call
8837 -- will change the Ekind of the components from E_Void to E_Component.
8839 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
8840 Record_Type_Definition (Empty, Derived_Type);
8842 -- STEP 5c: Process the record extension for non private tagged types
8844 elsif not Private_Extension then
8845 Expand_Record_Extension (Derived_Type, Type_Def);
8847 -- Note : previously in ASIS mode we set the Parent_Subtype of the
8848 -- derived type to propagate some semantic information. This led
8849 -- to other ASIS failures and has been removed.
8851 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
8852 -- implemented interfaces if we are in expansion mode
8855 and then Has_Interfaces (Derived_Type)
8857 Add_Interface_Tag_Components (N, Derived_Type);
8860 -- Analyze the record extension
8862 Record_Type_Definition
8863 (Record_Extension_Part (Type_Def), Derived_Type);
8868 -- Nothing else to do if there is an error in the derivation.
8869 -- An unusual case: the full view may be derived from a type in an
8870 -- instance, when the partial view was used illegally as an actual
8871 -- in that instance, leading to a circular definition.
8873 if Etype (Derived_Type) = Any_Type
8874 or else Etype (Parent_Type) = Derived_Type
8879 -- Set delayed freeze and then derive subprograms, we need to do
8880 -- this in this order so that derived subprograms inherit the
8881 -- derived freeze if necessary.
8883 Set_Has_Delayed_Freeze (Derived_Type);
8885 if Derive_Subps then
8886 Derive_Subprograms (Parent_Type, Derived_Type);
8889 -- If we have a private extension which defines a constrained derived
8890 -- type mark as constrained here after we have derived subprograms. See
8891 -- comment on point 9. just above the body of Build_Derived_Record_Type.
8893 if Private_Extension and then Inherit_Discrims then
8894 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
8895 Set_Is_Constrained (Derived_Type, True);
8896 Set_Discriminant_Constraint (Derived_Type, Discs);
8898 elsif Is_Constrained (Parent_Type) then
8900 (Derived_Type, True);
8901 Set_Discriminant_Constraint
8902 (Derived_Type, Discriminant_Constraint (Parent_Type));
8906 -- Update the class-wide type, which shares the now-completed entity
8907 -- list with its specific type. In case of underlying record views,
8908 -- we do not generate the corresponding class wide entity.
8911 and then not Is_Underlying_Record_View (Derived_Type)
8914 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
8916 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
8919 Check_Function_Writable_Actuals (N);
8920 end Build_Derived_Record_Type;
8922 ------------------------
8923 -- Build_Derived_Type --
8924 ------------------------
8926 procedure Build_Derived_Type
8928 Parent_Type : Entity_Id;
8929 Derived_Type : Entity_Id;
8930 Is_Completion : Boolean;
8931 Derive_Subps : Boolean := True)
8933 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
8936 -- Set common attributes
8938 Set_Scope (Derived_Type, Current_Scope);
8940 Set_Etype (Derived_Type, Parent_Base);
8941 Set_Ekind (Derived_Type, Ekind (Parent_Base));
8942 Set_Has_Task (Derived_Type, Has_Task (Parent_Base));
8943 Set_Has_Protected (Derived_Type, Has_Protected (Parent_Base));
8945 Set_Size_Info (Derived_Type, Parent_Type);
8946 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
8947 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
8948 Set_Disable_Controlled (Derived_Type, Disable_Controlled (Parent_Type));
8950 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
8951 Set_Is_Volatile (Derived_Type, Is_Volatile (Parent_Type));
8953 if Is_Tagged_Type (Derived_Type) then
8954 Set_No_Tagged_Streams_Pragma
8955 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
8958 -- If the parent has primitive routines, set the derived type link
8960 if Has_Primitive_Operations (Parent_Type) then
8961 Set_Derived_Type_Link (Parent_Base, Derived_Type);
8964 -- If the parent type is a private subtype, the convention on the base
8965 -- type may be set in the private part, and not propagated to the
8966 -- subtype until later, so we obtain the convention from the base type.
8968 Set_Convention (Derived_Type, Convention (Parent_Base));
8970 -- Set SSO default for record or array type
8972 if (Is_Array_Type (Derived_Type) or else Is_Record_Type (Derived_Type))
8973 and then Is_Base_Type (Derived_Type)
8975 Set_Default_SSO (Derived_Type);
8978 -- Propagate invariant information. The new type has invariants if
8979 -- they are inherited from the parent type, and these invariants can
8980 -- be further inherited, so both flags are set.
8982 -- We similarly inherit predicates
8984 if Has_Predicates (Parent_Type) then
8985 Set_Has_Predicates (Derived_Type);
8988 -- The derived type inherits the representation clauses of the parent
8990 Inherit_Rep_Item_Chain (Derived_Type, Parent_Type);
8992 -- Propagate the attributes related to pragma Default_Initial_Condition
8993 -- from the parent type to the private extension. A derived type always
8994 -- inherits the default initial condition flag from the parent type. If
8995 -- the derived type carries its own Default_Initial_Condition pragma,
8996 -- the flag is later reset in Analyze_Pragma. Note that both flags are
8997 -- mutually exclusive.
8999 Propagate_Default_Init_Cond_Attributes
9000 (From_Typ => Parent_Type,
9001 To_Typ => Derived_Type,
9002 Parent_To_Derivation => True);
9004 -- If the parent type has delayed rep aspects, then mark the derived
9005 -- type as possibly inheriting a delayed rep aspect.
9007 if Has_Delayed_Rep_Aspects (Parent_Type) then
9008 Set_May_Inherit_Delayed_Rep_Aspects (Derived_Type);
9011 -- Propagate the attributes related to pragma Ghost from the parent type
9012 -- to the derived type or type extension (SPARK RM 6.9(9)).
9014 if Is_Ghost_Entity (Parent_Type) then
9015 Set_Is_Ghost_Entity (Derived_Type);
9018 -- Type dependent processing
9020 case Ekind (Parent_Type) is
9021 when Numeric_Kind =>
9022 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
9025 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
9029 | Class_Wide_Kind =>
9030 Build_Derived_Record_Type
9031 (N, Parent_Type, Derived_Type, Derive_Subps);
9034 when Enumeration_Kind =>
9035 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
9038 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
9040 when Incomplete_Or_Private_Kind =>
9041 Build_Derived_Private_Type
9042 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
9044 -- For discriminated types, the derivation includes deriving
9045 -- primitive operations. For others it is done below.
9047 if Is_Tagged_Type (Parent_Type)
9048 or else Has_Discriminants (Parent_Type)
9049 or else (Present (Full_View (Parent_Type))
9050 and then Has_Discriminants (Full_View (Parent_Type)))
9055 when Concurrent_Kind =>
9056 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
9059 raise Program_Error;
9062 -- Nothing more to do if some error occurred
9064 if Etype (Derived_Type) = Any_Type then
9068 -- Set delayed freeze and then derive subprograms, we need to do this
9069 -- in this order so that derived subprograms inherit the derived freeze
9072 Set_Has_Delayed_Freeze (Derived_Type);
9074 if Derive_Subps then
9075 Derive_Subprograms (Parent_Type, Derived_Type);
9078 Set_Has_Primitive_Operations
9079 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
9080 end Build_Derived_Type;
9082 -----------------------
9083 -- Build_Discriminal --
9084 -----------------------
9086 procedure Build_Discriminal (Discrim : Entity_Id) is
9087 D_Minal : Entity_Id;
9088 CR_Disc : Entity_Id;
9091 -- A discriminal has the same name as the discriminant
9093 D_Minal := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
9095 Set_Ekind (D_Minal, E_In_Parameter);
9096 Set_Mechanism (D_Minal, Default_Mechanism);
9097 Set_Etype (D_Minal, Etype (Discrim));
9098 Set_Scope (D_Minal, Current_Scope);
9100 Set_Discriminal (Discrim, D_Minal);
9101 Set_Discriminal_Link (D_Minal, Discrim);
9103 -- For task types, build at once the discriminants of the corresponding
9104 -- record, which are needed if discriminants are used in entry defaults
9105 -- and in family bounds.
9107 if Is_Concurrent_Type (Current_Scope)
9109 Is_Limited_Type (Current_Scope)
9111 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
9113 Set_Ekind (CR_Disc, E_In_Parameter);
9114 Set_Mechanism (CR_Disc, Default_Mechanism);
9115 Set_Etype (CR_Disc, Etype (Discrim));
9116 Set_Scope (CR_Disc, Current_Scope);
9117 Set_Discriminal_Link (CR_Disc, Discrim);
9118 Set_CR_Discriminant (Discrim, CR_Disc);
9120 end Build_Discriminal;
9122 ------------------------------------
9123 -- Build_Discriminant_Constraints --
9124 ------------------------------------
9126 function Build_Discriminant_Constraints
9129 Derived_Def : Boolean := False) return Elist_Id
9131 C : constant Node_Id := Constraint (Def);
9132 Nb_Discr : constant Nat := Number_Discriminants (T);
9134 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
9135 -- Saves the expression corresponding to a given discriminant in T
9137 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
9138 -- Return the Position number within array Discr_Expr of a discriminant
9139 -- D within the discriminant list of the discriminated type T.
9141 procedure Process_Discriminant_Expression
9144 -- If this is a discriminant constraint on a partial view, do not
9145 -- generate an overflow check on the discriminant expression. The check
9146 -- will be generated when constraining the full view. Otherwise the
9147 -- backend creates duplicate symbols for the temporaries corresponding
9148 -- to the expressions to be checked, causing spurious assembler errors.
9154 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
9158 Disc := First_Discriminant (T);
9159 for J in Discr_Expr'Range loop
9164 Next_Discriminant (Disc);
9167 -- Note: Since this function is called on discriminants that are
9168 -- known to belong to the discriminated type, falling through the
9169 -- loop with no match signals an internal compiler error.
9171 raise Program_Error;
9174 -------------------------------------
9175 -- Process_Discriminant_Expression --
9176 -------------------------------------
9178 procedure Process_Discriminant_Expression
9182 BDT : constant Entity_Id := Base_Type (Etype (D));
9185 -- If this is a discriminant constraint on a partial view, do
9186 -- not generate an overflow on the discriminant expression. The
9187 -- check will be generated when constraining the full view.
9189 if Is_Private_Type (T)
9190 and then Present (Full_View (T))
9192 Analyze_And_Resolve (Expr, BDT, Suppress => Overflow_Check);
9194 Analyze_And_Resolve (Expr, BDT);
9196 end Process_Discriminant_Expression;
9198 -- Declarations local to Build_Discriminant_Constraints
9202 Elist : constant Elist_Id := New_Elmt_List;
9210 Discrim_Present : Boolean := False;
9212 -- Start of processing for Build_Discriminant_Constraints
9215 -- The following loop will process positional associations only.
9216 -- For a positional association, the (single) discriminant is
9217 -- implicitly specified by position, in textual order (RM 3.7.2).
9219 Discr := First_Discriminant (T);
9220 Constr := First (Constraints (C));
9221 for D in Discr_Expr'Range loop
9222 exit when Nkind (Constr) = N_Discriminant_Association;
9225 Error_Msg_N ("too few discriminants given in constraint", C);
9226 return New_Elmt_List;
9228 elsif Nkind (Constr) = N_Range
9229 or else (Nkind (Constr) = N_Attribute_Reference
9230 and then Attribute_Name (Constr) = Name_Range)
9233 ("a range is not a valid discriminant constraint", Constr);
9234 Discr_Expr (D) := Error;
9237 Process_Discriminant_Expression (Constr, Discr);
9238 Discr_Expr (D) := Constr;
9241 Next_Discriminant (Discr);
9245 if No (Discr) and then Present (Constr) then
9246 Error_Msg_N ("too many discriminants given in constraint", Constr);
9247 return New_Elmt_List;
9250 -- Named associations can be given in any order, but if both positional
9251 -- and named associations are used in the same discriminant constraint,
9252 -- then positional associations must occur first, at their normal
9253 -- position. Hence once a named association is used, the rest of the
9254 -- discriminant constraint must use only named associations.
9256 while Present (Constr) loop
9258 -- Positional association forbidden after a named association
9260 if Nkind (Constr) /= N_Discriminant_Association then
9261 Error_Msg_N ("positional association follows named one", Constr);
9262 return New_Elmt_List;
9264 -- Otherwise it is a named association
9267 -- E records the type of the discriminants in the named
9268 -- association. All the discriminants specified in the same name
9269 -- association must have the same type.
9273 -- Search the list of discriminants in T to see if the simple name
9274 -- given in the constraint matches any of them.
9276 Id := First (Selector_Names (Constr));
9277 while Present (Id) loop
9280 -- If Original_Discriminant is present, we are processing a
9281 -- generic instantiation and this is an instance node. We need
9282 -- to find the name of the corresponding discriminant in the
9283 -- actual record type T and not the name of the discriminant in
9284 -- the generic formal. Example:
9287 -- type G (D : int) is private;
9289 -- subtype W is G (D => 1);
9291 -- type Rec (X : int) is record ... end record;
9292 -- package Q is new P (G => Rec);
9294 -- At the point of the instantiation, formal type G is Rec
9295 -- and therefore when reanalyzing "subtype W is G (D => 1);"
9296 -- which really looks like "subtype W is Rec (D => 1);" at
9297 -- the point of instantiation, we want to find the discriminant
9298 -- that corresponds to D in Rec, i.e. X.
9300 if Present (Original_Discriminant (Id))
9301 and then In_Instance
9303 Discr := Find_Corresponding_Discriminant (Id, T);
9307 Discr := First_Discriminant (T);
9308 while Present (Discr) loop
9309 if Chars (Discr) = Chars (Id) then
9314 Next_Discriminant (Discr);
9318 Error_Msg_N ("& does not match any discriminant", Id);
9319 return New_Elmt_List;
9321 -- If the parent type is a generic formal, preserve the
9322 -- name of the discriminant for subsequent instances.
9323 -- see comment at the beginning of this if statement.
9325 elsif Is_Generic_Type (Root_Type (T)) then
9326 Set_Original_Discriminant (Id, Discr);
9330 Position := Pos_Of_Discr (T, Discr);
9332 if Present (Discr_Expr (Position)) then
9333 Error_Msg_N ("duplicate constraint for discriminant&", Id);
9336 -- Each discriminant specified in the same named association
9337 -- must be associated with a separate copy of the
9338 -- corresponding expression.
9340 if Present (Next (Id)) then
9341 Expr := New_Copy_Tree (Expression (Constr));
9342 Set_Parent (Expr, Parent (Expression (Constr)));
9344 Expr := Expression (Constr);
9347 Discr_Expr (Position) := Expr;
9348 Process_Discriminant_Expression (Expr, Discr);
9351 -- A discriminant association with more than one discriminant
9352 -- name is only allowed if the named discriminants are all of
9353 -- the same type (RM 3.7.1(8)).
9356 E := Base_Type (Etype (Discr));
9358 elsif Base_Type (Etype (Discr)) /= E then
9360 ("all discriminants in an association " &
9361 "must have the same type", Id);
9371 -- A discriminant constraint must provide exactly one value for each
9372 -- discriminant of the type (RM 3.7.1(8)).
9374 for J in Discr_Expr'Range loop
9375 if No (Discr_Expr (J)) then
9376 Error_Msg_N ("too few discriminants given in constraint", C);
9377 return New_Elmt_List;
9381 -- Determine if there are discriminant expressions in the constraint
9383 for J in Discr_Expr'Range loop
9384 if Denotes_Discriminant
9385 (Discr_Expr (J), Check_Concurrent => True)
9387 Discrim_Present := True;
9391 -- Build an element list consisting of the expressions given in the
9392 -- discriminant constraint and apply the appropriate checks. The list
9393 -- is constructed after resolving any named discriminant associations
9394 -- and therefore the expressions appear in the textual order of the
9397 Discr := First_Discriminant (T);
9398 for J in Discr_Expr'Range loop
9399 if Discr_Expr (J) /= Error then
9400 Append_Elmt (Discr_Expr (J), Elist);
9402 -- If any of the discriminant constraints is given by a
9403 -- discriminant and we are in a derived type declaration we
9404 -- have a discriminant renaming. Establish link between new
9405 -- and old discriminant.
9407 if Denotes_Discriminant (Discr_Expr (J)) then
9409 Set_Corresponding_Discriminant
9410 (Entity (Discr_Expr (J)), Discr);
9413 -- Force the evaluation of non-discriminant expressions.
9414 -- If we have found a discriminant in the constraint 3.4(26)
9415 -- and 3.8(18) demand that no range checks are performed are
9416 -- after evaluation. If the constraint is for a component
9417 -- definition that has a per-object constraint, expressions are
9418 -- evaluated but not checked either. In all other cases perform
9422 if Discrim_Present then
9425 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
9427 Has_Per_Object_Constraint
9428 (Defining_Identifier (Parent (Parent (Def))))
9432 elsif Is_Access_Type (Etype (Discr)) then
9433 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
9436 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
9439 Force_Evaluation (Discr_Expr (J));
9442 -- Check that the designated type of an access discriminant's
9443 -- expression is not a class-wide type unless the discriminant's
9444 -- designated type is also class-wide.
9446 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
9447 and then not Is_Class_Wide_Type
9448 (Designated_Type (Etype (Discr)))
9449 and then Etype (Discr_Expr (J)) /= Any_Type
9450 and then Is_Class_Wide_Type
9451 (Designated_Type (Etype (Discr_Expr (J))))
9453 Wrong_Type (Discr_Expr (J), Etype (Discr));
9455 elsif Is_Access_Type (Etype (Discr))
9456 and then not Is_Access_Constant (Etype (Discr))
9457 and then Is_Access_Type (Etype (Discr_Expr (J)))
9458 and then Is_Access_Constant (Etype (Discr_Expr (J)))
9461 ("constraint for discriminant& must be access to variable",
9466 Next_Discriminant (Discr);
9470 end Build_Discriminant_Constraints;
9472 ---------------------------------
9473 -- Build_Discriminated_Subtype --
9474 ---------------------------------
9476 procedure Build_Discriminated_Subtype
9480 Related_Nod : Node_Id;
9481 For_Access : Boolean := False)
9483 Has_Discrs : constant Boolean := Has_Discriminants (T);
9484 Constrained : constant Boolean :=
9486 and then not Is_Empty_Elmt_List (Elist)
9487 and then not Is_Class_Wide_Type (T))
9488 or else Is_Constrained (T);
9491 if Ekind (T) = E_Record_Type then
9493 Set_Ekind (Def_Id, E_Private_Subtype);
9494 Set_Is_For_Access_Subtype (Def_Id, True);
9496 Set_Ekind (Def_Id, E_Record_Subtype);
9499 -- Inherit preelaboration flag from base, for types for which it
9500 -- may have been set: records, private types, protected types.
9502 Set_Known_To_Have_Preelab_Init
9503 (Def_Id, Known_To_Have_Preelab_Init (T));
9505 elsif Ekind (T) = E_Task_Type then
9506 Set_Ekind (Def_Id, E_Task_Subtype);
9508 elsif Ekind (T) = E_Protected_Type then
9509 Set_Ekind (Def_Id, E_Protected_Subtype);
9510 Set_Known_To_Have_Preelab_Init
9511 (Def_Id, Known_To_Have_Preelab_Init (T));
9513 elsif Is_Private_Type (T) then
9514 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
9515 Set_Known_To_Have_Preelab_Init
9516 (Def_Id, Known_To_Have_Preelab_Init (T));
9518 -- Private subtypes may have private dependents
9520 Set_Private_Dependents (Def_Id, New_Elmt_List);
9522 elsif Is_Class_Wide_Type (T) then
9523 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
9526 -- Incomplete type. Attach subtype to list of dependents, to be
9527 -- completed with full view of parent type, unless is it the
9528 -- designated subtype of a record component within an init_proc.
9529 -- This last case arises for a component of an access type whose
9530 -- designated type is incomplete (e.g. a Taft Amendment type).
9531 -- The designated subtype is within an inner scope, and needs no
9532 -- elaboration, because only the access type is needed in the
9533 -- initialization procedure.
9535 Set_Ekind (Def_Id, Ekind (T));
9537 if For_Access and then Within_Init_Proc then
9540 Append_Elmt (Def_Id, Private_Dependents (T));
9544 Set_Etype (Def_Id, T);
9545 Init_Size_Align (Def_Id);
9546 Set_Has_Discriminants (Def_Id, Has_Discrs);
9547 Set_Is_Constrained (Def_Id, Constrained);
9549 Set_First_Entity (Def_Id, First_Entity (T));
9550 Set_Last_Entity (Def_Id, Last_Entity (T));
9551 Set_Has_Implicit_Dereference
9552 (Def_Id, Has_Implicit_Dereference (T));
9554 -- If the subtype is the completion of a private declaration, there may
9555 -- have been representation clauses for the partial view, and they must
9556 -- be preserved. Build_Derived_Type chains the inherited clauses with
9557 -- the ones appearing on the extension. If this comes from a subtype
9558 -- declaration, all clauses are inherited.
9560 if No (First_Rep_Item (Def_Id)) then
9561 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
9564 if Is_Tagged_Type (T) then
9565 Set_Is_Tagged_Type (Def_Id);
9566 Set_No_Tagged_Streams_Pragma (Def_Id, No_Tagged_Streams_Pragma (T));
9567 Make_Class_Wide_Type (Def_Id);
9570 Set_Stored_Constraint (Def_Id, No_Elist);
9573 Set_Discriminant_Constraint (Def_Id, Elist);
9574 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
9577 if Is_Tagged_Type (T) then
9579 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
9580 -- concurrent record type (which has the list of primitive
9583 if Ada_Version >= Ada_2005
9584 and then Is_Concurrent_Type (T)
9586 Set_Corresponding_Record_Type (Def_Id,
9587 Corresponding_Record_Type (T));
9589 Set_Direct_Primitive_Operations (Def_Id,
9590 Direct_Primitive_Operations (T));
9593 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
9596 -- Subtypes introduced by component declarations do not need to be
9597 -- marked as delayed, and do not get freeze nodes, because the semantics
9598 -- verifies that the parents of the subtypes are frozen before the
9599 -- enclosing record is frozen.
9601 if not Is_Type (Scope (Def_Id)) then
9602 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
9604 if Is_Private_Type (T)
9605 and then Present (Full_View (T))
9607 Conditional_Delay (Def_Id, Full_View (T));
9609 Conditional_Delay (Def_Id, T);
9613 if Is_Record_Type (T) then
9614 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
9617 and then not Is_Empty_Elmt_List (Elist)
9618 and then not For_Access
9620 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
9621 elsif not For_Access then
9622 Set_Cloned_Subtype (Def_Id, T);
9625 end Build_Discriminated_Subtype;
9627 ---------------------------
9628 -- Build_Itype_Reference --
9629 ---------------------------
9631 procedure Build_Itype_Reference
9635 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
9638 -- Itype references are only created for use by the back-end
9640 if Inside_A_Generic then
9643 Set_Itype (IR, Ityp);
9644 Insert_After (Nod, IR);
9646 end Build_Itype_Reference;
9648 ------------------------
9649 -- Build_Scalar_Bound --
9650 ------------------------
9652 function Build_Scalar_Bound
9655 Der_T : Entity_Id) return Node_Id
9657 New_Bound : Entity_Id;
9660 -- Note: not clear why this is needed, how can the original bound
9661 -- be unanalyzed at this point? and if it is, what business do we
9662 -- have messing around with it? and why is the base type of the
9663 -- parent type the right type for the resolution. It probably is
9664 -- not. It is OK for the new bound we are creating, but not for
9665 -- the old one??? Still if it never happens, no problem.
9667 Analyze_And_Resolve (Bound, Base_Type (Par_T));
9669 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
9670 New_Bound := New_Copy (Bound);
9671 Set_Etype (New_Bound, Der_T);
9672 Set_Analyzed (New_Bound);
9674 elsif Is_Entity_Name (Bound) then
9675 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
9677 -- The following is almost certainly wrong. What business do we have
9678 -- relocating a node (Bound) that is presumably still attached to
9679 -- the tree elsewhere???
9682 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
9685 Set_Etype (New_Bound, Der_T);
9687 end Build_Scalar_Bound;
9689 --------------------------------
9690 -- Build_Underlying_Full_View --
9691 --------------------------------
9693 procedure Build_Underlying_Full_View
9698 Loc : constant Source_Ptr := Sloc (N);
9699 Subt : constant Entity_Id :=
9700 Make_Defining_Identifier
9701 (Loc, New_External_Name (Chars (Typ), 'S'));
9708 procedure Set_Discriminant_Name (Id : Node_Id);
9709 -- If the derived type has discriminants, they may rename discriminants
9710 -- of the parent. When building the full view of the parent, we need to
9711 -- recover the names of the original discriminants if the constraint is
9712 -- given by named associations.
9714 ---------------------------
9715 -- Set_Discriminant_Name --
9716 ---------------------------
9718 procedure Set_Discriminant_Name (Id : Node_Id) is
9722 Set_Original_Discriminant (Id, Empty);
9724 if Has_Discriminants (Typ) then
9725 Disc := First_Discriminant (Typ);
9726 while Present (Disc) loop
9727 if Chars (Disc) = Chars (Id)
9728 and then Present (Corresponding_Discriminant (Disc))
9730 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
9732 Next_Discriminant (Disc);
9735 end Set_Discriminant_Name;
9737 -- Start of processing for Build_Underlying_Full_View
9740 if Nkind (N) = N_Full_Type_Declaration then
9741 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
9743 elsif Nkind (N) = N_Subtype_Declaration then
9744 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
9746 elsif Nkind (N) = N_Component_Declaration then
9749 (Constraint (Subtype_Indication (Component_Definition (N))));
9752 raise Program_Error;
9755 C := First (Constraints (Constr));
9756 while Present (C) loop
9757 if Nkind (C) = N_Discriminant_Association then
9758 Id := First (Selector_Names (C));
9759 while Present (Id) loop
9760 Set_Discriminant_Name (Id);
9769 Make_Subtype_Declaration (Loc,
9770 Defining_Identifier => Subt,
9771 Subtype_Indication =>
9772 Make_Subtype_Indication (Loc,
9773 Subtype_Mark => New_Occurrence_Of (Par, Loc),
9774 Constraint => New_Copy_Tree (Constr)));
9776 -- If this is a component subtype for an outer itype, it is not
9777 -- a list member, so simply set the parent link for analysis: if
9778 -- the enclosing type does not need to be in a declarative list,
9779 -- neither do the components.
9781 if Is_List_Member (N)
9782 and then Nkind (N) /= N_Component_Declaration
9784 Insert_Before (N, Indic);
9786 Set_Parent (Indic, Parent (N));
9790 Set_Underlying_Full_View (Typ, Full_View (Subt));
9791 end Build_Underlying_Full_View;
9793 -------------------------------
9794 -- Check_Abstract_Overriding --
9795 -------------------------------
9797 procedure Check_Abstract_Overriding (T : Entity_Id) is
9798 Alias_Subp : Entity_Id;
9804 procedure Check_Pragma_Implemented (Subp : Entity_Id);
9805 -- Ada 2012 (AI05-0030): Subprogram Subp overrides an interface routine
9806 -- which has pragma Implemented already set. Check whether Subp's entity
9807 -- kind conforms to the implementation kind of the overridden routine.
9809 procedure Check_Pragma_Implemented
9811 Iface_Subp : Entity_Id);
9812 -- Ada 2012 (AI05-0030): Subprogram Subp overrides interface routine
9813 -- Iface_Subp and both entities have pragma Implemented already set on
9814 -- them. Check whether the two implementation kinds are conforming.
9816 procedure Inherit_Pragma_Implemented
9818 Iface_Subp : Entity_Id);
9819 -- Ada 2012 (AI05-0030): Interface primitive Subp overrides interface
9820 -- subprogram Iface_Subp which has been marked by pragma Implemented.
9821 -- Propagate the implementation kind of Iface_Subp to Subp.
9823 ------------------------------
9824 -- Check_Pragma_Implemented --
9825 ------------------------------
9827 procedure Check_Pragma_Implemented (Subp : Entity_Id) is
9828 Iface_Alias : constant Entity_Id := Interface_Alias (Subp);
9829 Impl_Kind : constant Name_Id := Implementation_Kind (Iface_Alias);
9830 Subp_Alias : constant Entity_Id := Alias (Subp);
9831 Contr_Typ : Entity_Id;
9832 Impl_Subp : Entity_Id;
9835 -- Subp must have an alias since it is a hidden entity used to link
9836 -- an interface subprogram to its overriding counterpart.
9838 pragma Assert (Present (Subp_Alias));
9840 -- Handle aliases to synchronized wrappers
9842 Impl_Subp := Subp_Alias;
9844 if Is_Primitive_Wrapper (Impl_Subp) then
9845 Impl_Subp := Wrapped_Entity (Impl_Subp);
9848 -- Extract the type of the controlling formal
9850 Contr_Typ := Etype (First_Formal (Subp_Alias));
9852 if Is_Concurrent_Record_Type (Contr_Typ) then
9853 Contr_Typ := Corresponding_Concurrent_Type (Contr_Typ);
9856 -- An interface subprogram whose implementation kind is By_Entry must
9857 -- be implemented by an entry.
9859 if Impl_Kind = Name_By_Entry
9860 and then Ekind (Impl_Subp) /= E_Entry
9862 Error_Msg_Node_2 := Iface_Alias;
9864 ("type & must implement abstract subprogram & with an entry",
9865 Subp_Alias, Contr_Typ);
9867 elsif Impl_Kind = Name_By_Protected_Procedure then
9869 -- An interface subprogram whose implementation kind is By_
9870 -- Protected_Procedure cannot be implemented by a primitive
9871 -- procedure of a task type.
9873 if Ekind (Contr_Typ) /= E_Protected_Type then
9874 Error_Msg_Node_2 := Contr_Typ;
9876 ("interface subprogram & cannot be implemented by a " &
9877 "primitive procedure of task type &", Subp_Alias,
9880 -- An interface subprogram whose implementation kind is By_
9881 -- Protected_Procedure must be implemented by a procedure.
9883 elsif Ekind (Impl_Subp) /= E_Procedure then
9884 Error_Msg_Node_2 := Iface_Alias;
9886 ("type & must implement abstract subprogram & with a " &
9887 "procedure", Subp_Alias, Contr_Typ);
9889 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
9890 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
9892 Error_Msg_Name_1 := Impl_Kind;
9894 ("overriding operation& must have synchronization%",
9898 -- If primitive has Optional synchronization, overriding operation
9899 -- must match if it has an explicit synchronization..
9901 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
9902 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
9904 Error_Msg_Name_1 := Impl_Kind;
9906 ("overriding operation& must have syncrhonization%",
9909 end Check_Pragma_Implemented;
9911 ------------------------------
9912 -- Check_Pragma_Implemented --
9913 ------------------------------
9915 procedure Check_Pragma_Implemented
9917 Iface_Subp : Entity_Id)
9919 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
9920 Subp_Kind : constant Name_Id := Implementation_Kind (Subp);
9923 -- Ada 2012 (AI05-0030): The implementation kinds of an overridden
9924 -- and overriding subprogram are different. In general this is an
9925 -- error except when the implementation kind of the overridden
9926 -- subprograms is By_Any or Optional.
9928 if Iface_Kind /= Subp_Kind
9929 and then Iface_Kind /= Name_By_Any
9930 and then Iface_Kind /= Name_Optional
9932 if Iface_Kind = Name_By_Entry then
9934 ("incompatible implementation kind, overridden subprogram " &
9935 "is marked By_Entry", Subp);
9938 ("incompatible implementation kind, overridden subprogram " &
9939 "is marked By_Protected_Procedure", Subp);
9942 end Check_Pragma_Implemented;
9944 --------------------------------
9945 -- Inherit_Pragma_Implemented --
9946 --------------------------------
9948 procedure Inherit_Pragma_Implemented
9950 Iface_Subp : Entity_Id)
9952 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
9953 Loc : constant Source_Ptr := Sloc (Subp);
9954 Impl_Prag : Node_Id;
9957 -- Since the implementation kind is stored as a representation item
9958 -- rather than a flag, create a pragma node.
9962 Chars => Name_Implemented,
9963 Pragma_Argument_Associations => New_List (
9964 Make_Pragma_Argument_Association (Loc,
9965 Expression => New_Occurrence_Of (Subp, Loc)),
9967 Make_Pragma_Argument_Association (Loc,
9968 Expression => Make_Identifier (Loc, Iface_Kind))));
9970 -- The pragma doesn't need to be analyzed because it is internally
9971 -- built. It is safe to directly register it as a rep item since we
9972 -- are only interested in the characters of the implementation kind.
9974 Record_Rep_Item (Subp, Impl_Prag);
9975 end Inherit_Pragma_Implemented;
9977 -- Start of processing for Check_Abstract_Overriding
9980 Op_List := Primitive_Operations (T);
9982 -- Loop to check primitive operations
9984 Elmt := First_Elmt (Op_List);
9985 while Present (Elmt) loop
9986 Subp := Node (Elmt);
9987 Alias_Subp := Alias (Subp);
9989 -- Inherited subprograms are identified by the fact that they do not
9990 -- come from source, and the associated source location is the
9991 -- location of the first subtype of the derived type.
9993 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
9994 -- subprograms that "require overriding".
9996 -- Special exception, do not complain about failure to override the
9997 -- stream routines _Input and _Output, as well as the primitive
9998 -- operations used in dispatching selects since we always provide
9999 -- automatic overridings for these subprograms.
10001 -- The partial view of T may have been a private extension, for
10002 -- which inherited functions dispatching on result are abstract.
10003 -- If the full view is a null extension, there is no need for
10004 -- overriding in Ada 2005, but wrappers need to be built for them
10005 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
10007 if Is_Null_Extension (T)
10008 and then Has_Controlling_Result (Subp)
10009 and then Ada_Version >= Ada_2005
10010 and then Present (Alias_Subp)
10011 and then not Comes_From_Source (Subp)
10012 and then not Is_Abstract_Subprogram (Alias_Subp)
10013 and then not Is_Access_Type (Etype (Subp))
10017 -- Ada 2005 (AI-251): Internal entities of interfaces need no
10018 -- processing because this check is done with the aliased
10021 elsif Present (Interface_Alias (Subp)) then
10024 elsif (Is_Abstract_Subprogram (Subp)
10025 or else Requires_Overriding (Subp)
10027 (Has_Controlling_Result (Subp)
10028 and then Present (Alias_Subp)
10029 and then not Comes_From_Source (Subp)
10030 and then Sloc (Subp) = Sloc (First_Subtype (T))))
10031 and then not Is_TSS (Subp, TSS_Stream_Input)
10032 and then not Is_TSS (Subp, TSS_Stream_Output)
10033 and then not Is_Abstract_Type (T)
10034 and then not Is_Predefined_Interface_Primitive (Subp)
10036 -- Ada 2005 (AI-251): Do not consider hidden entities associated
10037 -- with abstract interface types because the check will be done
10038 -- with the aliased entity (otherwise we generate a duplicated
10041 and then not Present (Interface_Alias (Subp))
10043 if Present (Alias_Subp) then
10045 -- Only perform the check for a derived subprogram when the
10046 -- type has an explicit record extension. This avoids incorrect
10047 -- flagging of abstract subprograms for the case of a type
10048 -- without an extension that is derived from a formal type
10049 -- with a tagged actual (can occur within a private part).
10051 -- Ada 2005 (AI-391): In the case of an inherited function with
10052 -- a controlling result of the type, the rule does not apply if
10053 -- the type is a null extension (unless the parent function
10054 -- itself is abstract, in which case the function must still be
10055 -- be overridden). The expander will generate an overriding
10056 -- wrapper function calling the parent subprogram (see
10057 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
10059 Type_Def := Type_Definition (Parent (T));
10061 if Nkind (Type_Def) = N_Derived_Type_Definition
10062 and then Present (Record_Extension_Part (Type_Def))
10064 (Ada_Version < Ada_2005
10065 or else not Is_Null_Extension (T)
10066 or else Ekind (Subp) = E_Procedure
10067 or else not Has_Controlling_Result (Subp)
10068 or else Is_Abstract_Subprogram (Alias_Subp)
10069 or else Requires_Overriding (Subp)
10070 or else Is_Access_Type (Etype (Subp)))
10072 -- Avoid reporting error in case of abstract predefined
10073 -- primitive inherited from interface type because the
10074 -- body of internally generated predefined primitives
10075 -- of tagged types are generated later by Freeze_Type
10077 if Is_Interface (Root_Type (T))
10078 and then Is_Abstract_Subprogram (Subp)
10079 and then Is_Predefined_Dispatching_Operation (Subp)
10080 and then not Comes_From_Source (Ultimate_Alias (Subp))
10084 -- A null extension is not obliged to override an inherited
10085 -- procedure subject to pragma Extensions_Visible with value
10086 -- False and at least one controlling OUT parameter
10087 -- (SPARK RM 6.1.7(6)).
10089 elsif Is_Null_Extension (T)
10090 and then Is_EVF_Procedure (Subp)
10096 ("type must be declared abstract or & overridden",
10099 -- Traverse the whole chain of aliased subprograms to
10100 -- complete the error notification. This is especially
10101 -- useful for traceability of the chain of entities when
10102 -- the subprogram corresponds with an interface
10103 -- subprogram (which may be defined in another package).
10105 if Present (Alias_Subp) then
10111 while Present (Alias (E)) loop
10113 -- Avoid reporting redundant errors on entities
10114 -- inherited from interfaces
10116 if Sloc (E) /= Sloc (T) then
10117 Error_Msg_Sloc := Sloc (E);
10119 ("\& has been inherited #", T, Subp);
10125 Error_Msg_Sloc := Sloc (E);
10127 -- AI05-0068: report if there is an overriding
10128 -- non-abstract subprogram that is invisible.
10131 and then not Is_Abstract_Subprogram (E)
10134 ("\& subprogram# is not visible",
10137 -- Clarify the case where a non-null extension must
10138 -- override inherited procedure subject to pragma
10139 -- Extensions_Visible with value False and at least
10140 -- one controlling OUT param.
10142 elsif Is_EVF_Procedure (E) then
10144 ("\& # is subject to Extensions_Visible False",
10149 ("\& has been inherited from subprogram #",
10156 -- Ada 2005 (AI-345): Protected or task type implementing
10157 -- abstract interfaces.
10159 elsif Is_Concurrent_Record_Type (T)
10160 and then Present (Interfaces (T))
10162 -- There is no need to check here RM 9.4(11.9/3) since we
10163 -- are processing the corresponding record type and the
10164 -- mode of the overriding subprograms was verified by
10165 -- Check_Conformance when the corresponding concurrent
10166 -- type declaration was analyzed.
10169 ("interface subprogram & must be overridden", T, Subp);
10171 -- Examine primitive operations of synchronized type to find
10172 -- homonyms that have the wrong profile.
10178 Prim := First_Entity (Corresponding_Concurrent_Type (T));
10179 while Present (Prim) loop
10180 if Chars (Prim) = Chars (Subp) then
10182 ("profile is not type conformant with prefixed "
10183 & "view profile of inherited operation&",
10187 Next_Entity (Prim);
10193 Error_Msg_Node_2 := T;
10195 ("abstract subprogram& not allowed for type&", Subp);
10197 -- Also post unconditional warning on the type (unconditional
10198 -- so that if there are more than one of these cases, we get
10199 -- them all, and not just the first one).
10201 Error_Msg_Node_2 := Subp;
10202 Error_Msg_N ("nonabstract type& has abstract subprogram&!", T);
10205 -- A subprogram subject to pragma Extensions_Visible with value
10206 -- "True" cannot override a subprogram subject to the same pragma
10207 -- with value "False" (SPARK RM 6.1.7(5)).
10209 elsif Extensions_Visible_Status (Subp) = Extensions_Visible_True
10210 and then Present (Overridden_Operation (Subp))
10211 and then Extensions_Visible_Status (Overridden_Operation (Subp)) =
10212 Extensions_Visible_False
10214 Error_Msg_Sloc := Sloc (Overridden_Operation (Subp));
10216 ("subprogram & with Extensions_Visible True cannot override "
10217 & "subprogram # with Extensions_Visible False", Subp);
10220 -- Ada 2012 (AI05-0030): Perform checks related to pragma Implemented
10222 -- Subp is an expander-generated procedure which maps an interface
10223 -- alias to a protected wrapper. The interface alias is flagged by
10224 -- pragma Implemented. Ensure that Subp is a procedure when the
10225 -- implementation kind is By_Protected_Procedure or an entry when
10228 if Ada_Version >= Ada_2012
10229 and then Is_Hidden (Subp)
10230 and then Present (Interface_Alias (Subp))
10231 and then Has_Rep_Pragma (Interface_Alias (Subp), Name_Implemented)
10233 Check_Pragma_Implemented (Subp);
10236 -- Subp is an interface primitive which overrides another interface
10237 -- primitive marked with pragma Implemented.
10239 if Ada_Version >= Ada_2012
10240 and then Present (Overridden_Operation (Subp))
10241 and then Has_Rep_Pragma
10242 (Overridden_Operation (Subp), Name_Implemented)
10244 -- If the overriding routine is also marked by Implemented, check
10245 -- that the two implementation kinds are conforming.
10247 if Has_Rep_Pragma (Subp, Name_Implemented) then
10248 Check_Pragma_Implemented
10250 Iface_Subp => Overridden_Operation (Subp));
10252 -- Otherwise the overriding routine inherits the implementation
10253 -- kind from the overridden subprogram.
10256 Inherit_Pragma_Implemented
10258 Iface_Subp => Overridden_Operation (Subp));
10262 -- If the operation is a wrapper for a synchronized primitive, it
10263 -- may be called indirectly through a dispatching select. We assume
10264 -- that it will be referenced elsewhere indirectly, and suppress
10265 -- warnings about an unused entity.
10267 if Is_Primitive_Wrapper (Subp)
10268 and then Present (Wrapped_Entity (Subp))
10270 Set_Referenced (Wrapped_Entity (Subp));
10275 end Check_Abstract_Overriding;
10277 ------------------------------------------------
10278 -- Check_Access_Discriminant_Requires_Limited --
10279 ------------------------------------------------
10281 procedure Check_Access_Discriminant_Requires_Limited
10286 -- A discriminant_specification for an access discriminant shall appear
10287 -- only in the declaration for a task or protected type, or for a type
10288 -- with the reserved word 'limited' in its definition or in one of its
10289 -- ancestors (RM 3.7(10)).
10291 -- AI-0063: The proper condition is that type must be immutably limited,
10292 -- or else be a partial view.
10294 if Nkind (Discriminant_Type (D)) = N_Access_Definition then
10295 if Is_Limited_View (Current_Scope)
10297 (Nkind (Parent (Current_Scope)) = N_Private_Type_Declaration
10298 and then Limited_Present (Parent (Current_Scope)))
10304 ("access discriminants allowed only for limited types", Loc);
10307 end Check_Access_Discriminant_Requires_Limited;
10309 -----------------------------------
10310 -- Check_Aliased_Component_Types --
10311 -----------------------------------
10313 procedure Check_Aliased_Component_Types (T : Entity_Id) is
10317 -- ??? Also need to check components of record extensions, but not
10318 -- components of protected types (which are always limited).
10320 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
10321 -- types to be unconstrained. This is safe because it is illegal to
10322 -- create access subtypes to such types with explicit discriminant
10325 if not Is_Limited_Type (T) then
10326 if Ekind (T) = E_Record_Type then
10327 C := First_Component (T);
10328 while Present (C) loop
10330 and then Has_Discriminants (Etype (C))
10331 and then not Is_Constrained (Etype (C))
10332 and then not In_Instance_Body
10333 and then Ada_Version < Ada_2005
10336 ("aliased component must be constrained (RM 3.6(11))",
10340 Next_Component (C);
10343 elsif Ekind (T) = E_Array_Type then
10344 if Has_Aliased_Components (T)
10345 and then Has_Discriminants (Component_Type (T))
10346 and then not Is_Constrained (Component_Type (T))
10347 and then not In_Instance_Body
10348 and then Ada_Version < Ada_2005
10351 ("aliased component type must be constrained (RM 3.6(11))",
10356 end Check_Aliased_Component_Types;
10358 ---------------------------------------
10359 -- Check_Anonymous_Access_Components --
10360 ---------------------------------------
10362 procedure Check_Anonymous_Access_Components
10363 (Typ_Decl : Node_Id;
10366 Comp_List : Node_Id)
10368 Loc : constant Source_Ptr := Sloc (Typ_Decl);
10369 Anon_Access : Entity_Id;
10372 Comp_Def : Node_Id;
10374 Type_Def : Node_Id;
10376 procedure Build_Incomplete_Type_Declaration;
10377 -- If the record type contains components that include an access to the
10378 -- current record, then create an incomplete type declaration for the
10379 -- record, to be used as the designated type of the anonymous access.
10380 -- This is done only once, and only if there is no previous partial
10381 -- view of the type.
10383 function Designates_T (Subt : Node_Id) return Boolean;
10384 -- Check whether a node designates the enclosing record type, or 'Class
10387 function Mentions_T (Acc_Def : Node_Id) return Boolean;
10388 -- Check whether an access definition includes a reference to
10389 -- the enclosing record type. The reference can be a subtype mark
10390 -- in the access definition itself, a 'Class attribute reference, or
10391 -- recursively a reference appearing in a parameter specification
10392 -- or result definition of an access_to_subprogram definition.
10394 --------------------------------------
10395 -- Build_Incomplete_Type_Declaration --
10396 --------------------------------------
10398 procedure Build_Incomplete_Type_Declaration is
10403 -- Is_Tagged indicates whether the type is tagged. It is tagged if
10404 -- it's "is new ... with record" or else "is tagged record ...".
10406 Is_Tagged : constant Boolean :=
10407 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
10409 Present (Record_Extension_Part (Type_Definition (Typ_Decl))))
10411 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
10412 and then Tagged_Present (Type_Definition (Typ_Decl)));
10415 -- If there is a previous partial view, no need to create a new one
10416 -- If the partial view, given by Prev, is incomplete, If Prev is
10417 -- a private declaration, full declaration is flagged accordingly.
10419 if Prev /= Typ then
10421 Make_Class_Wide_Type (Prev);
10422 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
10423 Set_Etype (Class_Wide_Type (Typ), Typ);
10428 elsif Has_Private_Declaration (Typ) then
10430 -- If we refer to T'Class inside T, and T is the completion of a
10431 -- private type, then make sure the class-wide type exists.
10434 Make_Class_Wide_Type (Typ);
10439 -- If there was a previous anonymous access type, the incomplete
10440 -- type declaration will have been created already.
10442 elsif Present (Current_Entity (Typ))
10443 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
10444 and then Full_View (Current_Entity (Typ)) = Typ
10447 and then Comes_From_Source (Current_Entity (Typ))
10448 and then not Is_Tagged_Type (Current_Entity (Typ))
10450 Make_Class_Wide_Type (Typ);
10452 ("incomplete view of tagged type should be declared tagged??",
10453 Parent (Current_Entity (Typ)));
10458 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
10459 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
10461 -- Type has already been inserted into the current scope. Remove
10462 -- it, and add incomplete declaration for type, so that subsequent
10463 -- anonymous access types can use it. The entity is unchained from
10464 -- the homonym list and from immediate visibility. After analysis,
10465 -- the entity in the incomplete declaration becomes immediately
10466 -- visible in the record declaration that follows.
10468 H := Current_Entity (Typ);
10471 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
10474 and then Homonym (H) /= Typ
10476 H := Homonym (Typ);
10479 Set_Homonym (H, Homonym (Typ));
10482 Insert_Before (Typ_Decl, Decl);
10484 Set_Full_View (Inc_T, Typ);
10488 -- Create a common class-wide type for both views, and set the
10489 -- Etype of the class-wide type to the full view.
10491 Make_Class_Wide_Type (Inc_T);
10492 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
10493 Set_Etype (Class_Wide_Type (Typ), Typ);
10496 end Build_Incomplete_Type_Declaration;
10502 function Designates_T (Subt : Node_Id) return Boolean is
10503 Type_Id : constant Name_Id := Chars (Typ);
10505 function Names_T (Nam : Node_Id) return Boolean;
10506 -- The record type has not been introduced in the current scope
10507 -- yet, so we must examine the name of the type itself, either
10508 -- an identifier T, or an expanded name of the form P.T, where
10509 -- P denotes the current scope.
10515 function Names_T (Nam : Node_Id) return Boolean is
10517 if Nkind (Nam) = N_Identifier then
10518 return Chars (Nam) = Type_Id;
10520 elsif Nkind (Nam) = N_Selected_Component then
10521 if Chars (Selector_Name (Nam)) = Type_Id then
10522 if Nkind (Prefix (Nam)) = N_Identifier then
10523 return Chars (Prefix (Nam)) = Chars (Current_Scope);
10525 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
10526 return Chars (Selector_Name (Prefix (Nam))) =
10527 Chars (Current_Scope);
10541 -- Start of processing for Designates_T
10544 if Nkind (Subt) = N_Identifier then
10545 return Chars (Subt) = Type_Id;
10547 -- Reference can be through an expanded name which has not been
10548 -- analyzed yet, and which designates enclosing scopes.
10550 elsif Nkind (Subt) = N_Selected_Component then
10551 if Names_T (Subt) then
10554 -- Otherwise it must denote an entity that is already visible.
10555 -- The access definition may name a subtype of the enclosing
10556 -- type, if there is a previous incomplete declaration for it.
10559 Find_Selected_Component (Subt);
10561 Is_Entity_Name (Subt)
10562 and then Scope (Entity (Subt)) = Current_Scope
10564 (Chars (Base_Type (Entity (Subt))) = Type_Id
10566 (Is_Class_Wide_Type (Entity (Subt))
10568 Chars (Etype (Base_Type (Entity (Subt)))) =
10572 -- A reference to the current type may appear as the prefix of
10573 -- a 'Class attribute.
10575 elsif Nkind (Subt) = N_Attribute_Reference
10576 and then Attribute_Name (Subt) = Name_Class
10578 return Names_T (Prefix (Subt));
10589 function Mentions_T (Acc_Def : Node_Id) return Boolean is
10590 Param_Spec : Node_Id;
10592 Acc_Subprg : constant Node_Id :=
10593 Access_To_Subprogram_Definition (Acc_Def);
10596 if No (Acc_Subprg) then
10597 return Designates_T (Subtype_Mark (Acc_Def));
10600 -- Component is an access_to_subprogram: examine its formals,
10601 -- and result definition in the case of an access_to_function.
10603 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
10604 while Present (Param_Spec) loop
10605 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
10606 and then Mentions_T (Parameter_Type (Param_Spec))
10610 elsif Designates_T (Parameter_Type (Param_Spec)) then
10617 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
10618 if Nkind (Result_Definition (Acc_Subprg)) =
10619 N_Access_Definition
10621 return Mentions_T (Result_Definition (Acc_Subprg));
10623 return Designates_T (Result_Definition (Acc_Subprg));
10630 -- Start of processing for Check_Anonymous_Access_Components
10633 if No (Comp_List) then
10637 Comp := First (Component_Items (Comp_List));
10638 while Present (Comp) loop
10639 if Nkind (Comp) = N_Component_Declaration
10641 (Access_Definition (Component_Definition (Comp)))
10643 Mentions_T (Access_Definition (Component_Definition (Comp)))
10645 Comp_Def := Component_Definition (Comp);
10647 Access_To_Subprogram_Definition (Access_Definition (Comp_Def));
10649 Build_Incomplete_Type_Declaration;
10650 Anon_Access := Make_Temporary (Loc, 'S');
10652 -- Create a declaration for the anonymous access type: either
10653 -- an access_to_object or an access_to_subprogram.
10655 if Present (Acc_Def) then
10656 if Nkind (Acc_Def) = N_Access_Function_Definition then
10658 Make_Access_Function_Definition (Loc,
10659 Parameter_Specifications =>
10660 Parameter_Specifications (Acc_Def),
10661 Result_Definition => Result_Definition (Acc_Def));
10664 Make_Access_Procedure_Definition (Loc,
10665 Parameter_Specifications =>
10666 Parameter_Specifications (Acc_Def));
10671 Make_Access_To_Object_Definition (Loc,
10672 Subtype_Indication =>
10674 (Subtype_Mark (Access_Definition (Comp_Def))));
10676 Set_Constant_Present
10677 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
10679 (Type_Def, All_Present (Access_Definition (Comp_Def)));
10682 Set_Null_Exclusion_Present
10684 Null_Exclusion_Present (Access_Definition (Comp_Def)));
10687 Make_Full_Type_Declaration (Loc,
10688 Defining_Identifier => Anon_Access,
10689 Type_Definition => Type_Def);
10691 Insert_Before (Typ_Decl, Decl);
10694 -- If an access to subprogram, create the extra formals
10696 if Present (Acc_Def) then
10697 Create_Extra_Formals (Designated_Type (Anon_Access));
10699 -- If an access to object, preserve entity of designated type,
10700 -- for ASIS use, before rewriting the component definition.
10707 Desig := Entity (Subtype_Indication (Type_Def));
10709 -- If the access definition is to the current record,
10710 -- the visible entity at this point is an incomplete
10711 -- type. Retrieve the full view to simplify ASIS queries
10713 if Ekind (Desig) = E_Incomplete_Type then
10714 Desig := Full_View (Desig);
10718 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
10723 Make_Component_Definition (Loc,
10724 Subtype_Indication =>
10725 New_Occurrence_Of (Anon_Access, Loc)));
10727 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
10728 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
10730 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
10733 Set_Is_Local_Anonymous_Access (Anon_Access);
10739 if Present (Variant_Part (Comp_List)) then
10743 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
10744 while Present (V) loop
10745 Check_Anonymous_Access_Components
10746 (Typ_Decl, Typ, Prev, Component_List (V));
10747 Next_Non_Pragma (V);
10751 end Check_Anonymous_Access_Components;
10753 ----------------------
10754 -- Check_Completion --
10755 ----------------------
10757 procedure Check_Completion (Body_Id : Node_Id := Empty) is
10760 procedure Post_Error;
10761 -- Post error message for lack of completion for entity E
10767 procedure Post_Error is
10768 procedure Missing_Body;
10769 -- Output missing body message
10775 procedure Missing_Body is
10777 -- Spec is in same unit, so we can post on spec
10779 if In_Same_Source_Unit (Body_Id, E) then
10780 Error_Msg_N ("missing body for &", E);
10782 -- Spec is in a separate unit, so we have to post on the body
10785 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
10789 -- Start of processing for Post_Error
10792 if not Comes_From_Source (E) then
10793 if Ekind_In (E, E_Task_Type, E_Protected_Type) then
10795 -- It may be an anonymous protected type created for a
10796 -- single variable. Post error on variable, if present.
10802 Var := First_Entity (Current_Scope);
10803 while Present (Var) loop
10804 exit when Etype (Var) = E
10805 and then Comes_From_Source (Var);
10810 if Present (Var) then
10817 -- If a generated entity has no completion, then either previous
10818 -- semantic errors have disabled the expansion phase, or else we had
10819 -- missing subunits, or else we are compiling without expansion,
10820 -- or else something is very wrong.
10822 if not Comes_From_Source (E) then
10824 (Serious_Errors_Detected > 0
10825 or else Configurable_Run_Time_Violations > 0
10826 or else Subunits_Missing
10827 or else not Expander_Active);
10830 -- Here for source entity
10833 -- Here if no body to post the error message, so we post the error
10834 -- on the declaration that has no completion. This is not really
10835 -- the right place to post it, think about this later ???
10837 if No (Body_Id) then
10838 if Is_Type (E) then
10840 ("missing full declaration for }", Parent (E), E);
10842 Error_Msg_NE ("missing body for &", Parent (E), E);
10845 -- Package body has no completion for a declaration that appears
10846 -- in the corresponding spec. Post error on the body, with a
10847 -- reference to the non-completed declaration.
10850 Error_Msg_Sloc := Sloc (E);
10852 if Is_Type (E) then
10853 Error_Msg_NE ("missing full declaration for }!", Body_Id, E);
10855 elsif Is_Overloadable (E)
10856 and then Current_Entity_In_Scope (E) /= E
10858 -- It may be that the completion is mistyped and appears as
10859 -- a distinct overloading of the entity.
10862 Candidate : constant Entity_Id :=
10863 Current_Entity_In_Scope (E);
10864 Decl : constant Node_Id :=
10865 Unit_Declaration_Node (Candidate);
10868 if Is_Overloadable (Candidate)
10869 and then Ekind (Candidate) = Ekind (E)
10870 and then Nkind (Decl) = N_Subprogram_Body
10871 and then Acts_As_Spec (Decl)
10873 Check_Type_Conformant (Candidate, E);
10889 Pack_Id : constant Entity_Id := Current_Scope;
10891 -- Start of processing for Check_Completion
10894 E := First_Entity (Pack_Id);
10895 while Present (E) loop
10896 if Is_Intrinsic_Subprogram (E) then
10899 -- The following situation requires special handling: a child unit
10900 -- that appears in the context clause of the body of its parent:
10902 -- procedure Parent.Child (...);
10904 -- with Parent.Child;
10905 -- package body Parent is
10907 -- Here Parent.Child appears as a local entity, but should not be
10908 -- flagged as requiring completion, because it is a compilation
10911 -- Ignore missing completion for a subprogram that does not come from
10912 -- source (including the _Call primitive operation of RAS types,
10913 -- which has to have the flag Comes_From_Source for other purposes):
10914 -- we assume that the expander will provide the missing completion.
10915 -- In case of previous errors, other expansion actions that provide
10916 -- bodies for null procedures with not be invoked, so inhibit message
10919 -- Note that E_Operator is not in the list that follows, because
10920 -- this kind is reserved for predefined operators, that are
10921 -- intrinsic and do not need completion.
10923 elsif Ekind_In (E, E_Function,
10925 E_Generic_Function,
10926 E_Generic_Procedure)
10928 if Has_Completion (E) then
10931 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
10934 elsif Is_Subprogram (E)
10935 and then (not Comes_From_Source (E)
10936 or else Chars (E) = Name_uCall)
10941 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
10945 elsif Nkind (Parent (E)) = N_Procedure_Specification
10946 and then Null_Present (Parent (E))
10947 and then Serious_Errors_Detected > 0
10955 elsif Is_Entry (E) then
10956 if not Has_Completion (E) and then
10957 (Ekind (Scope (E)) = E_Protected_Object
10958 or else Ekind (Scope (E)) = E_Protected_Type)
10963 elsif Is_Package_Or_Generic_Package (E) then
10964 if Unit_Requires_Body (E) then
10965 if not Has_Completion (E)
10966 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
10972 elsif not Is_Child_Unit (E) then
10973 May_Need_Implicit_Body (E);
10976 -- A formal incomplete type (Ada 2012) does not require a completion;
10977 -- other incomplete type declarations do.
10979 elsif Ekind (E) = E_Incomplete_Type
10980 and then No (Underlying_Type (E))
10981 and then not Is_Generic_Type (E)
10985 elsif Ekind_In (E, E_Task_Type, E_Protected_Type)
10986 and then not Has_Completion (E)
10990 -- A single task declared in the current scope is a constant, verify
10991 -- that the body of its anonymous type is in the same scope. If the
10992 -- task is defined elsewhere, this may be a renaming declaration for
10993 -- which no completion is needed.
10995 elsif Ekind (E) = E_Constant
10996 and then Ekind (Etype (E)) = E_Task_Type
10997 and then not Has_Completion (Etype (E))
10998 and then Scope (Etype (E)) = Current_Scope
11002 elsif Ekind (E) = E_Protected_Object
11003 and then not Has_Completion (Etype (E))
11007 elsif Ekind (E) = E_Record_Type then
11008 if Is_Tagged_Type (E) then
11009 Check_Abstract_Overriding (E);
11010 Check_Conventions (E);
11013 Check_Aliased_Component_Types (E);
11015 elsif Ekind (E) = E_Array_Type then
11016 Check_Aliased_Component_Types (E);
11022 end Check_Completion;
11024 ------------------------------------
11025 -- Check_CPP_Type_Has_No_Defaults --
11026 ------------------------------------
11028 procedure Check_CPP_Type_Has_No_Defaults (T : Entity_Id) is
11029 Tdef : constant Node_Id := Type_Definition (Declaration_Node (T));
11034 -- Obtain the component list
11036 if Nkind (Tdef) = N_Record_Definition then
11037 Clist := Component_List (Tdef);
11038 else pragma Assert (Nkind (Tdef) = N_Derived_Type_Definition);
11039 Clist := Component_List (Record_Extension_Part (Tdef));
11042 -- Check all components to ensure no default expressions
11044 if Present (Clist) then
11045 Comp := First (Component_Items (Clist));
11046 while Present (Comp) loop
11047 if Present (Expression (Comp)) then
11049 ("component of imported 'C'P'P type cannot have "
11050 & "default expression", Expression (Comp));
11056 end Check_CPP_Type_Has_No_Defaults;
11058 ----------------------------
11059 -- Check_Delta_Expression --
11060 ----------------------------
11062 procedure Check_Delta_Expression (E : Node_Id) is
11064 if not (Is_Real_Type (Etype (E))) then
11065 Wrong_Type (E, Any_Real);
11067 elsif not Is_OK_Static_Expression (E) then
11068 Flag_Non_Static_Expr
11069 ("non-static expression used for delta value!", E);
11071 elsif not UR_Is_Positive (Expr_Value_R (E)) then
11072 Error_Msg_N ("delta expression must be positive", E);
11078 -- If any of above errors occurred, then replace the incorrect
11079 -- expression by the real 0.1, which should prevent further errors.
11082 Make_Real_Literal (Sloc (E), Ureal_Tenth));
11083 Analyze_And_Resolve (E, Standard_Float);
11084 end Check_Delta_Expression;
11086 -----------------------------
11087 -- Check_Digits_Expression --
11088 -----------------------------
11090 procedure Check_Digits_Expression (E : Node_Id) is
11092 if not (Is_Integer_Type (Etype (E))) then
11093 Wrong_Type (E, Any_Integer);
11095 elsif not Is_OK_Static_Expression (E) then
11096 Flag_Non_Static_Expr
11097 ("non-static expression used for digits value!", E);
11099 elsif Expr_Value (E) <= 0 then
11100 Error_Msg_N ("digits value must be greater than zero", E);
11106 -- If any of above errors occurred, then replace the incorrect
11107 -- expression by the integer 1, which should prevent further errors.
11109 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
11110 Analyze_And_Resolve (E, Standard_Integer);
11112 end Check_Digits_Expression;
11114 --------------------------
11115 -- Check_Initialization --
11116 --------------------------
11118 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
11120 -- Special processing for limited types
11122 if Is_Limited_Type (T)
11123 and then not In_Instance
11124 and then not In_Inlined_Body
11126 if not OK_For_Limited_Init (T, Exp) then
11128 -- In GNAT mode, this is just a warning, to allow it to be evilly
11129 -- turned off. Otherwise it is a real error.
11133 ("??cannot initialize entities of limited type!", Exp);
11135 elsif Ada_Version < Ada_2005 then
11137 -- The side effect removal machinery may generate illegal Ada
11138 -- code to avoid the usage of access types and 'reference in
11139 -- SPARK mode. Since this is legal code with respect to theorem
11140 -- proving, do not emit the error.
11143 and then Nkind (Exp) = N_Function_Call
11144 and then Nkind (Parent (Exp)) = N_Object_Declaration
11145 and then not Comes_From_Source
11146 (Defining_Identifier (Parent (Exp)))
11152 ("cannot initialize entities of limited type", Exp);
11153 Explain_Limited_Type (T, Exp);
11157 -- Specialize error message according to kind of illegal
11158 -- initial expression.
11160 if Nkind (Exp) = N_Type_Conversion
11161 and then Nkind (Expression (Exp)) = N_Function_Call
11164 ("illegal context for call"
11165 & " to function with limited result", Exp);
11169 ("initialization of limited object requires aggregate "
11170 & "or function call", Exp);
11176 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag gets
11177 -- set unless we can be sure that no range check is required.
11179 if (GNATprove_Mode or not Expander_Active)
11180 and then Is_Scalar_Type (T)
11181 and then not Is_In_Range (Exp, T, Assume_Valid => True)
11183 Set_Do_Range_Check (Exp);
11185 end Check_Initialization;
11187 ----------------------
11188 -- Check_Interfaces --
11189 ----------------------
11191 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
11192 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
11195 Iface_Def : Node_Id;
11196 Iface_Typ : Entity_Id;
11197 Parent_Node : Node_Id;
11199 Is_Task : Boolean := False;
11200 -- Set True if parent type or any progenitor is a task interface
11202 Is_Protected : Boolean := False;
11203 -- Set True if parent type or any progenitor is a protected interface
11205 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
11206 -- Check that a progenitor is compatible with declaration. If an error
11207 -- message is output, it is posted on Error_Node.
11213 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
11214 Iface_Id : constant Entity_Id :=
11215 Defining_Identifier (Parent (Iface_Def));
11216 Type_Def : Node_Id;
11219 if Nkind (N) = N_Private_Extension_Declaration then
11222 Type_Def := Type_Definition (N);
11225 if Is_Task_Interface (Iface_Id) then
11228 elsif Is_Protected_Interface (Iface_Id) then
11229 Is_Protected := True;
11232 if Is_Synchronized_Interface (Iface_Id) then
11234 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
11235 -- extension derived from a synchronized interface must explicitly
11236 -- be declared synchronized, because the full view will be a
11237 -- synchronized type.
11239 if Nkind (N) = N_Private_Extension_Declaration then
11240 if not Synchronized_Present (N) then
11242 ("private extension of& must be explicitly synchronized",
11246 -- However, by 3.9.4(16/2), a full type that is a record extension
11247 -- is never allowed to derive from a synchronized interface (note
11248 -- that interfaces must be excluded from this check, because those
11249 -- are represented by derived type definitions in some cases).
11251 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11252 and then not Interface_Present (Type_Definition (N))
11254 Error_Msg_N ("record extension cannot derive from synchronized "
11255 & "interface", Error_Node);
11259 -- Check that the characteristics of the progenitor are compatible
11260 -- with the explicit qualifier in the declaration.
11261 -- The check only applies to qualifiers that come from source.
11262 -- Limited_Present also appears in the declaration of corresponding
11263 -- records, and the check does not apply to them.
11265 if Limited_Present (Type_Def)
11267 Is_Concurrent_Record_Type (Defining_Identifier (N))
11269 if Is_Limited_Interface (Parent_Type)
11270 and then not Is_Limited_Interface (Iface_Id)
11273 ("progenitor & must be limited interface",
11274 Error_Node, Iface_Id);
11277 (Task_Present (Iface_Def)
11278 or else Protected_Present (Iface_Def)
11279 or else Synchronized_Present (Iface_Def))
11280 and then Nkind (N) /= N_Private_Extension_Declaration
11281 and then not Error_Posted (N)
11284 ("progenitor & must be limited interface",
11285 Error_Node, Iface_Id);
11288 -- Protected interfaces can only inherit from limited, synchronized
11289 -- or protected interfaces.
11291 elsif Nkind (N) = N_Full_Type_Declaration
11292 and then Protected_Present (Type_Def)
11294 if Limited_Present (Iface_Def)
11295 or else Synchronized_Present (Iface_Def)
11296 or else Protected_Present (Iface_Def)
11300 elsif Task_Present (Iface_Def) then
11301 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11302 & "from task interface", Error_Node);
11305 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11306 & "from non-limited interface", Error_Node);
11309 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
11310 -- limited and synchronized.
11312 elsif Synchronized_Present (Type_Def) then
11313 if Limited_Present (Iface_Def)
11314 or else Synchronized_Present (Iface_Def)
11318 elsif Protected_Present (Iface_Def)
11319 and then Nkind (N) /= N_Private_Extension_Declaration
11321 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11322 & "from protected interface", Error_Node);
11324 elsif Task_Present (Iface_Def)
11325 and then Nkind (N) /= N_Private_Extension_Declaration
11327 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11328 & "from task interface", Error_Node);
11330 elsif not Is_Limited_Interface (Iface_Id) then
11331 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11332 & "from non-limited interface", Error_Node);
11335 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
11336 -- synchronized or task interfaces.
11338 elsif Nkind (N) = N_Full_Type_Declaration
11339 and then Task_Present (Type_Def)
11341 if Limited_Present (Iface_Def)
11342 or else Synchronized_Present (Iface_Def)
11343 or else Task_Present (Iface_Def)
11347 elsif Protected_Present (Iface_Def) then
11348 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11349 & "protected interface", Error_Node);
11352 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11353 & "non-limited interface", Error_Node);
11358 -- Start of processing for Check_Interfaces
11361 if Is_Interface (Parent_Type) then
11362 if Is_Task_Interface (Parent_Type) then
11365 elsif Is_Protected_Interface (Parent_Type) then
11366 Is_Protected := True;
11370 if Nkind (N) = N_Private_Extension_Declaration then
11372 -- Check that progenitors are compatible with declaration
11374 Iface := First (Interface_List (Def));
11375 while Present (Iface) loop
11376 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11378 Parent_Node := Parent (Base_Type (Iface_Typ));
11379 Iface_Def := Type_Definition (Parent_Node);
11381 if not Is_Interface (Iface_Typ) then
11382 Diagnose_Interface (Iface, Iface_Typ);
11384 Check_Ifaces (Iface_Def, Iface);
11390 if Is_Task and Is_Protected then
11392 ("type cannot derive from task and protected interface", N);
11398 -- Full type declaration of derived type.
11399 -- Check compatibility with parent if it is interface type
11401 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11402 and then Is_Interface (Parent_Type)
11404 Parent_Node := Parent (Parent_Type);
11406 -- More detailed checks for interface varieties
11409 (Iface_Def => Type_Definition (Parent_Node),
11410 Error_Node => Subtype_Indication (Type_Definition (N)));
11413 Iface := First (Interface_List (Def));
11414 while Present (Iface) loop
11415 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11417 Parent_Node := Parent (Base_Type (Iface_Typ));
11418 Iface_Def := Type_Definition (Parent_Node);
11420 if not Is_Interface (Iface_Typ) then
11421 Diagnose_Interface (Iface, Iface_Typ);
11424 -- "The declaration of a specific descendant of an interface
11425 -- type freezes the interface type" RM 13.14
11427 Freeze_Before (N, Iface_Typ);
11428 Check_Ifaces (Iface_Def, Error_Node => Iface);
11434 if Is_Task and Is_Protected then
11436 ("type cannot derive from task and protected interface", N);
11438 end Check_Interfaces;
11440 ------------------------------------
11441 -- Check_Or_Process_Discriminants --
11442 ------------------------------------
11444 -- If an incomplete or private type declaration was already given for the
11445 -- type, the discriminants may have already been processed if they were
11446 -- present on the incomplete declaration. In this case a full conformance
11447 -- check has been performed in Find_Type_Name, and we then recheck here
11448 -- some properties that can't be checked on the partial view alone.
11449 -- Otherwise we call Process_Discriminants.
11451 procedure Check_Or_Process_Discriminants
11454 Prev : Entity_Id := Empty)
11457 if Has_Discriminants (T) then
11459 -- Discriminants are already set on T if they were already present
11460 -- on the partial view. Make them visible to component declarations.
11464 -- Discriminant on T (full view) referencing expr on partial view
11466 Prev_D : Entity_Id;
11467 -- Entity of corresponding discriminant on partial view
11470 -- Discriminant specification for full view, expression is
11471 -- the syntactic copy on full view (which has been checked for
11472 -- conformance with partial view), only used here to post error
11476 D := First_Discriminant (T);
11477 New_D := First (Discriminant_Specifications (N));
11478 while Present (D) loop
11479 Prev_D := Current_Entity (D);
11480 Set_Current_Entity (D);
11481 Set_Is_Immediately_Visible (D);
11482 Set_Homonym (D, Prev_D);
11484 -- Handle the case where there is an untagged partial view and
11485 -- the full view is tagged: must disallow discriminants with
11486 -- defaults, unless compiling for Ada 2012, which allows a
11487 -- limited tagged type to have defaulted discriminants (see
11488 -- AI05-0214). However, suppress error here if it was already
11489 -- reported on the default expression of the partial view.
11491 if Is_Tagged_Type (T)
11492 and then Present (Expression (Parent (D)))
11493 and then (not Is_Limited_Type (Current_Scope)
11494 or else Ada_Version < Ada_2012)
11495 and then not Error_Posted (Expression (Parent (D)))
11497 if Ada_Version >= Ada_2012 then
11499 ("discriminants of nonlimited tagged type cannot have "
11501 Expression (New_D));
11504 ("discriminants of tagged type cannot have defaults",
11505 Expression (New_D));
11509 -- Ada 2005 (AI-230): Access discriminant allowed in
11510 -- non-limited record types.
11512 if Ada_Version < Ada_2005 then
11514 -- This restriction gets applied to the full type here. It
11515 -- has already been applied earlier to the partial view.
11517 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
11520 Next_Discriminant (D);
11525 elsif Present (Discriminant_Specifications (N)) then
11526 Process_Discriminants (N, Prev);
11528 end Check_Or_Process_Discriminants;
11530 ----------------------
11531 -- Check_Real_Bound --
11532 ----------------------
11534 procedure Check_Real_Bound (Bound : Node_Id) is
11536 if not Is_Real_Type (Etype (Bound)) then
11538 ("bound in real type definition must be of real type", Bound);
11540 elsif not Is_OK_Static_Expression (Bound) then
11541 Flag_Non_Static_Expr
11542 ("non-static expression used for real type bound!", Bound);
11549 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
11551 Resolve (Bound, Standard_Float);
11552 end Check_Real_Bound;
11554 ------------------------------
11555 -- Complete_Private_Subtype --
11556 ------------------------------
11558 procedure Complete_Private_Subtype
11561 Full_Base : Entity_Id;
11562 Related_Nod : Node_Id)
11564 Save_Next_Entity : Entity_Id;
11565 Save_Homonym : Entity_Id;
11568 -- Set semantic attributes for (implicit) private subtype completion.
11569 -- If the full type has no discriminants, then it is a copy of the
11570 -- full view of the base. Otherwise, it is a subtype of the base with
11571 -- a possible discriminant constraint. Save and restore the original
11572 -- Next_Entity field of full to ensure that the calls to Copy_Node do
11573 -- not corrupt the entity chain.
11575 -- Note that the type of the full view is the same entity as the type
11576 -- of the partial view. In this fashion, the subtype has access to the
11577 -- correct view of the parent.
11579 Save_Next_Entity := Next_Entity (Full);
11580 Save_Homonym := Homonym (Priv);
11582 case Ekind (Full_Base) is
11583 when E_Record_Type |
11589 Copy_Node (Priv, Full);
11591 Set_Has_Discriminants
11592 (Full, Has_Discriminants (Full_Base));
11593 Set_Has_Unknown_Discriminants
11594 (Full, Has_Unknown_Discriminants (Full_Base));
11595 Set_First_Entity (Full, First_Entity (Full_Base));
11596 Set_Last_Entity (Full, Last_Entity (Full_Base));
11598 -- If the underlying base type is constrained, we know that the
11599 -- full view of the subtype is constrained as well (the converse
11600 -- is not necessarily true).
11602 if Is_Constrained (Full_Base) then
11603 Set_Is_Constrained (Full);
11607 Copy_Node (Full_Base, Full);
11609 Set_Chars (Full, Chars (Priv));
11610 Conditional_Delay (Full, Priv);
11611 Set_Sloc (Full, Sloc (Priv));
11614 Set_Next_Entity (Full, Save_Next_Entity);
11615 Set_Homonym (Full, Save_Homonym);
11616 Set_Associated_Node_For_Itype (Full, Related_Nod);
11618 -- Set common attributes for all subtypes: kind, convention, etc.
11620 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
11621 Set_Convention (Full, Convention (Full_Base));
11623 -- The Etype of the full view is inconsistent. Gigi needs to see the
11624 -- structural full view, which is what the current scheme gives: the
11625 -- Etype of the full view is the etype of the full base. However, if the
11626 -- full base is a derived type, the full view then looks like a subtype
11627 -- of the parent, not a subtype of the full base. If instead we write:
11629 -- Set_Etype (Full, Full_Base);
11631 -- then we get inconsistencies in the front-end (confusion between
11632 -- views). Several outstanding bugs are related to this ???
11634 Set_Is_First_Subtype (Full, False);
11635 Set_Scope (Full, Scope (Priv));
11636 Set_Size_Info (Full, Full_Base);
11637 Set_RM_Size (Full, RM_Size (Full_Base));
11638 Set_Is_Itype (Full);
11640 -- A subtype of a private-type-without-discriminants, whose full-view
11641 -- has discriminants with default expressions, is not constrained.
11643 if not Has_Discriminants (Priv) then
11644 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
11646 if Has_Discriminants (Full_Base) then
11647 Set_Discriminant_Constraint
11648 (Full, Discriminant_Constraint (Full_Base));
11650 -- The partial view may have been indefinite, the full view
11653 Set_Has_Unknown_Discriminants
11654 (Full, Has_Unknown_Discriminants (Full_Base));
11658 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
11659 Set_Depends_On_Private (Full, Has_Private_Component (Full));
11661 -- Freeze the private subtype entity if its parent is delayed, and not
11662 -- already frozen. We skip this processing if the type is an anonymous
11663 -- subtype of a record component, or is the corresponding record of a
11664 -- protected type, since these are processed when the enclosing type
11667 if not Is_Type (Scope (Full)) then
11668 Set_Has_Delayed_Freeze (Full,
11669 Has_Delayed_Freeze (Full_Base)
11670 and then (not Is_Frozen (Full_Base)));
11673 Set_Freeze_Node (Full, Empty);
11674 Set_Is_Frozen (Full, False);
11675 Set_Full_View (Priv, Full);
11677 if Has_Discriminants (Full) then
11678 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
11679 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
11681 if Has_Unknown_Discriminants (Full) then
11682 Set_Discriminant_Constraint (Full, No_Elist);
11686 if Ekind (Full_Base) = E_Record_Type
11687 and then Has_Discriminants (Full_Base)
11688 and then Has_Discriminants (Priv) -- might not, if errors
11689 and then not Has_Unknown_Discriminants (Priv)
11690 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
11692 Create_Constrained_Components
11693 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
11695 -- If the full base is itself derived from private, build a congruent
11696 -- subtype of its underlying type, for use by the back end. For a
11697 -- constrained record component, the declaration cannot be placed on
11698 -- the component list, but it must nevertheless be built an analyzed, to
11699 -- supply enough information for Gigi to compute the size of component.
11701 elsif Ekind (Full_Base) in Private_Kind
11702 and then Is_Derived_Type (Full_Base)
11703 and then Has_Discriminants (Full_Base)
11704 and then (Ekind (Current_Scope) /= E_Record_Subtype)
11706 if not Is_Itype (Priv)
11708 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
11710 Build_Underlying_Full_View
11711 (Parent (Priv), Full, Etype (Full_Base));
11713 elsif Nkind (Related_Nod) = N_Component_Declaration then
11714 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
11717 elsif Is_Record_Type (Full_Base) then
11719 -- Show Full is simply a renaming of Full_Base
11721 Set_Cloned_Subtype (Full, Full_Base);
11724 -- It is unsafe to share the bounds of a scalar type, because the Itype
11725 -- is elaborated on demand, and if a bound is non-static then different
11726 -- orders of elaboration in different units will lead to different
11727 -- external symbols.
11729 if Is_Scalar_Type (Full_Base) then
11730 Set_Scalar_Range (Full,
11731 Make_Range (Sloc (Related_Nod),
11733 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
11735 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
11737 -- This completion inherits the bounds of the full parent, but if
11738 -- the parent is an unconstrained floating point type, so is the
11741 if Is_Floating_Point_Type (Full_Base) then
11742 Set_Includes_Infinities
11743 (Scalar_Range (Full), Has_Infinities (Full_Base));
11747 -- ??? It seems that a lot of fields are missing that should be copied
11748 -- from Full_Base to Full. Here are some that are introduced in a
11749 -- non-disruptive way but a cleanup is necessary.
11751 if Is_Tagged_Type (Full_Base) then
11752 Set_Is_Tagged_Type (Full);
11753 Set_Direct_Primitive_Operations
11754 (Full, Direct_Primitive_Operations (Full_Base));
11755 Set_No_Tagged_Streams_Pragma
11756 (Full, No_Tagged_Streams_Pragma (Full_Base));
11758 -- Inherit class_wide type of full_base in case the partial view was
11759 -- not tagged. Otherwise it has already been created when the private
11760 -- subtype was analyzed.
11762 if No (Class_Wide_Type (Full)) then
11763 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
11766 -- If this is a subtype of a protected or task type, constrain its
11767 -- corresponding record, unless this is a subtype without constraints,
11768 -- i.e. a simple renaming as with an actual subtype in an instance.
11770 elsif Is_Concurrent_Type (Full_Base) then
11771 if Has_Discriminants (Full)
11772 and then Present (Corresponding_Record_Type (Full_Base))
11774 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
11776 Set_Corresponding_Record_Type (Full,
11777 Constrain_Corresponding_Record
11778 (Full, Corresponding_Record_Type (Full_Base), Related_Nod));
11781 Set_Corresponding_Record_Type (Full,
11782 Corresponding_Record_Type (Full_Base));
11786 -- Link rep item chain, and also setting of Has_Predicates from private
11787 -- subtype to full subtype, since we will need these on the full subtype
11788 -- to create the predicate function. Note that the full subtype may
11789 -- already have rep items, inherited from the full view of the base
11790 -- type, so we must be sure not to overwrite these entries.
11795 Next_Item : Node_Id;
11798 Item := First_Rep_Item (Full);
11800 -- If no existing rep items on full type, we can just link directly
11801 -- to the list of items on the private type, if any exist.. Same if
11802 -- the rep items are only those inherited from the base
11805 or else Nkind (Item) /= N_Aspect_Specification
11806 or else Entity (Item) = Full_Base)
11807 and then Present (First_Rep_Item (Priv))
11809 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
11811 -- Otherwise, search to the end of items currently linked to the full
11812 -- subtype and append the private items to the end. However, if Priv
11813 -- and Full already have the same list of rep items, then the append
11814 -- is not done, as that would create a circularity.
11816 elsif Item /= First_Rep_Item (Priv) then
11819 Next_Item := Next_Rep_Item (Item);
11820 exit when No (Next_Item);
11823 -- If the private view has aspect specifications, the full view
11824 -- inherits them. Since these aspects may already have been
11825 -- attached to the full view during derivation, do not append
11826 -- them if already present.
11828 if Item = First_Rep_Item (Priv) then
11834 -- And link the private type items at the end of the chain
11837 Set_Next_Rep_Item (Item, First_Rep_Item (Priv));
11842 -- Make sure Has_Predicates is set on full type if it is set on the
11843 -- private type. Note that it may already be set on the full type and
11844 -- if so, we don't want to unset it. Similarly, propagate information
11845 -- about delayed aspects, because the corresponding pragmas must be
11846 -- analyzed when one of the views is frozen. This last step is needed
11847 -- in particular when the full type is a scalar type for which an
11848 -- anonymous base type is constructed.
11850 if Has_Predicates (Priv) then
11851 Set_Has_Predicates (Full);
11854 if Has_Delayed_Aspects (Priv) then
11855 Set_Has_Delayed_Aspects (Full);
11857 end Complete_Private_Subtype;
11859 ----------------------------
11860 -- Constant_Redeclaration --
11861 ----------------------------
11863 procedure Constant_Redeclaration
11868 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
11869 Obj_Def : constant Node_Id := Object_Definition (N);
11872 procedure Check_Possible_Deferred_Completion
11873 (Prev_Id : Entity_Id;
11874 Prev_Obj_Def : Node_Id;
11875 Curr_Obj_Def : Node_Id);
11876 -- Determine whether the two object definitions describe the partial
11877 -- and the full view of a constrained deferred constant. Generate
11878 -- a subtype for the full view and verify that it statically matches
11879 -- the subtype of the partial view.
11881 procedure Check_Recursive_Declaration (Typ : Entity_Id);
11882 -- If deferred constant is an access type initialized with an allocator,
11883 -- check whether there is an illegal recursion in the definition,
11884 -- through a default value of some record subcomponent. This is normally
11885 -- detected when generating init procs, but requires this additional
11886 -- mechanism when expansion is disabled.
11888 ----------------------------------------
11889 -- Check_Possible_Deferred_Completion --
11890 ----------------------------------------
11892 procedure Check_Possible_Deferred_Completion
11893 (Prev_Id : Entity_Id;
11894 Prev_Obj_Def : Node_Id;
11895 Curr_Obj_Def : Node_Id)
11898 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
11899 and then Present (Constraint (Prev_Obj_Def))
11900 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
11901 and then Present (Constraint (Curr_Obj_Def))
11904 Loc : constant Source_Ptr := Sloc (N);
11905 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'S');
11906 Decl : constant Node_Id :=
11907 Make_Subtype_Declaration (Loc,
11908 Defining_Identifier => Def_Id,
11909 Subtype_Indication =>
11910 Relocate_Node (Curr_Obj_Def));
11913 Insert_Before_And_Analyze (N, Decl);
11914 Set_Etype (Id, Def_Id);
11916 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
11917 Error_Msg_Sloc := Sloc (Prev_Id);
11918 Error_Msg_N ("subtype does not statically match deferred "
11919 & "declaration #", N);
11923 end Check_Possible_Deferred_Completion;
11925 ---------------------------------
11926 -- Check_Recursive_Declaration --
11927 ---------------------------------
11929 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
11933 if Is_Record_Type (Typ) then
11934 Comp := First_Component (Typ);
11935 while Present (Comp) loop
11936 if Comes_From_Source (Comp) then
11937 if Present (Expression (Parent (Comp)))
11938 and then Is_Entity_Name (Expression (Parent (Comp)))
11939 and then Entity (Expression (Parent (Comp))) = Prev
11941 Error_Msg_Sloc := Sloc (Parent (Comp));
11943 ("illegal circularity with declaration for & #",
11947 elsif Is_Record_Type (Etype (Comp)) then
11948 Check_Recursive_Declaration (Etype (Comp));
11952 Next_Component (Comp);
11955 end Check_Recursive_Declaration;
11957 -- Start of processing for Constant_Redeclaration
11960 if Nkind (Parent (Prev)) = N_Object_Declaration then
11961 if Nkind (Object_Definition
11962 (Parent (Prev))) = N_Subtype_Indication
11964 -- Find type of new declaration. The constraints of the two
11965 -- views must match statically, but there is no point in
11966 -- creating an itype for the full view.
11968 if Nkind (Obj_Def) = N_Subtype_Indication then
11969 Find_Type (Subtype_Mark (Obj_Def));
11970 New_T := Entity (Subtype_Mark (Obj_Def));
11973 Find_Type (Obj_Def);
11974 New_T := Entity (Obj_Def);
11980 -- The full view may impose a constraint, even if the partial
11981 -- view does not, so construct the subtype.
11983 New_T := Find_Type_Of_Object (Obj_Def, N);
11988 -- Current declaration is illegal, diagnosed below in Enter_Name
11994 -- If previous full declaration or a renaming declaration exists, or if
11995 -- a homograph is present, let Enter_Name handle it, either with an
11996 -- error or with the removal of an overridden implicit subprogram.
11997 -- The previous one is a full declaration if it has an expression
11998 -- (which in the case of an aggregate is indicated by the Init flag).
12000 if Ekind (Prev) /= E_Constant
12001 or else Nkind (Parent (Prev)) = N_Object_Renaming_Declaration
12002 or else Present (Expression (Parent (Prev)))
12003 or else Has_Init_Expression (Parent (Prev))
12004 or else Present (Full_View (Prev))
12008 -- Verify that types of both declarations match, or else that both types
12009 -- are anonymous access types whose designated subtypes statically match
12010 -- (as allowed in Ada 2005 by AI-385).
12012 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
12014 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
12015 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
12016 or else Is_Access_Constant (Etype (New_T)) /=
12017 Is_Access_Constant (Etype (Prev))
12018 or else Can_Never_Be_Null (Etype (New_T)) /=
12019 Can_Never_Be_Null (Etype (Prev))
12020 or else Null_Exclusion_Present (Parent (Prev)) /=
12021 Null_Exclusion_Present (Parent (Id))
12022 or else not Subtypes_Statically_Match
12023 (Designated_Type (Etype (Prev)),
12024 Designated_Type (Etype (New_T))))
12026 Error_Msg_Sloc := Sloc (Prev);
12027 Error_Msg_N ("type does not match declaration#", N);
12028 Set_Full_View (Prev, Id);
12029 Set_Etype (Id, Any_Type);
12031 -- A deferred constant whose type is an anonymous array is always
12032 -- illegal (unless imported). A detailed error message might be
12033 -- helpful for Ada beginners.
12035 if Nkind (Object_Definition (Parent (Prev)))
12036 = N_Constrained_Array_Definition
12037 and then Nkind (Object_Definition (N))
12038 = N_Constrained_Array_Definition
12040 Error_Msg_N ("\each anonymous array is a distinct type", N);
12041 Error_Msg_N ("a deferred constant must have a named type",
12042 Object_Definition (Parent (Prev)));
12046 Null_Exclusion_Present (Parent (Prev))
12047 and then not Null_Exclusion_Present (N)
12049 Error_Msg_Sloc := Sloc (Prev);
12050 Error_Msg_N ("null-exclusion does not match declaration#", N);
12051 Set_Full_View (Prev, Id);
12052 Set_Etype (Id, Any_Type);
12054 -- If so, process the full constant declaration
12057 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
12058 -- the deferred declaration is constrained, then the subtype defined
12059 -- by the subtype_indication in the full declaration shall match it
12062 Check_Possible_Deferred_Completion
12064 Prev_Obj_Def => Object_Definition (Parent (Prev)),
12065 Curr_Obj_Def => Obj_Def);
12067 Set_Full_View (Prev, Id);
12068 Set_Is_Public (Id, Is_Public (Prev));
12069 Set_Is_Internal (Id);
12070 Append_Entity (Id, Current_Scope);
12072 -- Check ALIASED present if present before (RM 7.4(7))
12074 if Is_Aliased (Prev)
12075 and then not Aliased_Present (N)
12077 Error_Msg_Sloc := Sloc (Prev);
12078 Error_Msg_N ("ALIASED required (see declaration #)", N);
12081 -- Check that placement is in private part and that the incomplete
12082 -- declaration appeared in the visible part.
12084 if Ekind (Current_Scope) = E_Package
12085 and then not In_Private_Part (Current_Scope)
12087 Error_Msg_Sloc := Sloc (Prev);
12089 ("full constant for declaration # must be in private part", N);
12091 elsif Ekind (Current_Scope) = E_Package
12093 List_Containing (Parent (Prev)) /=
12094 Visible_Declarations (Package_Specification (Current_Scope))
12097 ("deferred constant must be declared in visible part",
12101 if Is_Access_Type (T)
12102 and then Nkind (Expression (N)) = N_Allocator
12104 Check_Recursive_Declaration (Designated_Type (T));
12107 -- A deferred constant is a visible entity. If type has invariants,
12108 -- verify that the initial value satisfies them.
12110 if Has_Invariants (T) and then Present (Invariant_Procedure (T)) then
12112 Make_Invariant_Call (New_Occurrence_Of (Prev, Sloc (N))));
12115 end Constant_Redeclaration;
12117 ----------------------
12118 -- Constrain_Access --
12119 ----------------------
12121 procedure Constrain_Access
12122 (Def_Id : in out Entity_Id;
12124 Related_Nod : Node_Id)
12126 T : constant Entity_Id := Entity (Subtype_Mark (S));
12127 Desig_Type : constant Entity_Id := Designated_Type (T);
12128 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
12129 Constraint_OK : Boolean := True;
12132 if Is_Array_Type (Desig_Type) then
12133 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
12135 elsif (Is_Record_Type (Desig_Type)
12136 or else Is_Incomplete_Or_Private_Type (Desig_Type))
12137 and then not Is_Constrained (Desig_Type)
12139 -- ??? The following code is a temporary bypass to ignore a
12140 -- discriminant constraint on access type if it is constraining
12141 -- the current record. Avoid creating the implicit subtype of the
12142 -- record we are currently compiling since right now, we cannot
12143 -- handle these. For now, just return the access type itself.
12145 if Desig_Type = Current_Scope
12146 and then No (Def_Id)
12148 Set_Ekind (Desig_Subtype, E_Record_Subtype);
12149 Def_Id := Entity (Subtype_Mark (S));
12151 -- This call added to ensure that the constraint is analyzed
12152 -- (needed for a B test). Note that we still return early from
12153 -- this procedure to avoid recursive processing. ???
12155 Constrain_Discriminated_Type
12156 (Desig_Subtype, S, Related_Nod, For_Access => True);
12160 -- Enforce rule that the constraint is illegal if there is an
12161 -- unconstrained view of the designated type. This means that the
12162 -- partial view (either a private type declaration or a derivation
12163 -- from a private type) has no discriminants. (Defect Report
12164 -- 8652/0008, Technical Corrigendum 1, checked by ACATS B371001).
12166 -- Rule updated for Ada 2005: The private type is said to have
12167 -- a constrained partial view, given that objects of the type
12168 -- can be declared. Furthermore, the rule applies to all access
12169 -- types, unlike the rule concerning default discriminants (see
12172 if (Ekind (T) = E_General_Access_Type or else Ada_Version >= Ada_2005)
12173 and then Has_Private_Declaration (Desig_Type)
12174 and then In_Open_Scopes (Scope (Desig_Type))
12175 and then Has_Discriminants (Desig_Type)
12178 Pack : constant Node_Id :=
12179 Unit_Declaration_Node (Scope (Desig_Type));
12184 if Nkind (Pack) = N_Package_Declaration then
12185 Decls := Visible_Declarations (Specification (Pack));
12186 Decl := First (Decls);
12187 while Present (Decl) loop
12188 if (Nkind (Decl) = N_Private_Type_Declaration
12189 and then Chars (Defining_Identifier (Decl)) =
12190 Chars (Desig_Type))
12193 (Nkind (Decl) = N_Full_Type_Declaration
12195 Chars (Defining_Identifier (Decl)) =
12197 and then Is_Derived_Type (Desig_Type)
12199 Has_Private_Declaration (Etype (Desig_Type)))
12201 if No (Discriminant_Specifications (Decl)) then
12203 ("cannot constrain access type if designated "
12204 & "type has constrained partial view", S);
12216 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
12217 For_Access => True);
12219 elsif Is_Concurrent_Type (Desig_Type)
12220 and then not Is_Constrained (Desig_Type)
12222 Constrain_Concurrent (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
12225 Error_Msg_N ("invalid constraint on access type", S);
12227 -- We simply ignore an invalid constraint
12229 Desig_Subtype := Desig_Type;
12230 Constraint_OK := False;
12233 if No (Def_Id) then
12234 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
12236 Set_Ekind (Def_Id, E_Access_Subtype);
12239 if Constraint_OK then
12240 Set_Etype (Def_Id, Base_Type (T));
12242 if Is_Private_Type (Desig_Type) then
12243 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
12246 Set_Etype (Def_Id, Any_Type);
12249 Set_Size_Info (Def_Id, T);
12250 Set_Is_Constrained (Def_Id, Constraint_OK);
12251 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
12252 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12253 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
12255 Conditional_Delay (Def_Id, T);
12257 -- AI-363 : Subtypes of general access types whose designated types have
12258 -- default discriminants are disallowed. In instances, the rule has to
12259 -- be checked against the actual, of which T is the subtype. In a
12260 -- generic body, the rule is checked assuming that the actual type has
12261 -- defaulted discriminants.
12263 if Ada_Version >= Ada_2005 or else Warn_On_Ada_2005_Compatibility then
12264 if Ekind (Base_Type (T)) = E_General_Access_Type
12265 and then Has_Defaulted_Discriminants (Desig_Type)
12267 if Ada_Version < Ada_2005 then
12269 ("access subtype of general access type would not " &
12270 "be allowed in Ada 2005?y?", S);
12273 ("access subtype of general access type not allowed", S);
12276 Error_Msg_N ("\discriminants have defaults", S);
12278 elsif Is_Access_Type (T)
12279 and then Is_Generic_Type (Desig_Type)
12280 and then Has_Discriminants (Desig_Type)
12281 and then In_Package_Body (Current_Scope)
12283 if Ada_Version < Ada_2005 then
12285 ("access subtype would not be allowed in generic body "
12286 & "in Ada 2005?y?", S);
12289 ("access subtype not allowed in generic body", S);
12293 ("\designated type is a discriminated formal", S);
12296 end Constrain_Access;
12298 ---------------------
12299 -- Constrain_Array --
12300 ---------------------
12302 procedure Constrain_Array
12303 (Def_Id : in out Entity_Id;
12305 Related_Nod : Node_Id;
12306 Related_Id : Entity_Id;
12307 Suffix : Character)
12309 C : constant Node_Id := Constraint (SI);
12310 Number_Of_Constraints : Nat := 0;
12313 Constraint_OK : Boolean := True;
12316 T := Entity (Subtype_Mark (SI));
12318 if Is_Access_Type (T) then
12319 T := Designated_Type (T);
12322 -- If an index constraint follows a subtype mark in a subtype indication
12323 -- then the type or subtype denoted by the subtype mark must not already
12324 -- impose an index constraint. The subtype mark must denote either an
12325 -- unconstrained array type or an access type whose designated type
12326 -- is such an array type... (RM 3.6.1)
12328 if Is_Constrained (T) then
12329 Error_Msg_N ("array type is already constrained", Subtype_Mark (SI));
12330 Constraint_OK := False;
12333 S := First (Constraints (C));
12334 while Present (S) loop
12335 Number_Of_Constraints := Number_Of_Constraints + 1;
12339 -- In either case, the index constraint must provide a discrete
12340 -- range for each index of the array type and the type of each
12341 -- discrete range must be the same as that of the corresponding
12342 -- index. (RM 3.6.1)
12344 if Number_Of_Constraints /= Number_Dimensions (T) then
12345 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
12346 Constraint_OK := False;
12349 S := First (Constraints (C));
12350 Index := First_Index (T);
12353 -- Apply constraints to each index type
12355 for J in 1 .. Number_Of_Constraints loop
12356 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
12364 if No (Def_Id) then
12366 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
12367 Set_Parent (Def_Id, Related_Nod);
12370 Set_Ekind (Def_Id, E_Array_Subtype);
12373 Set_Size_Info (Def_Id, (T));
12374 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12375 Set_Etype (Def_Id, Base_Type (T));
12377 if Constraint_OK then
12378 Set_First_Index (Def_Id, First (Constraints (C)));
12380 Set_First_Index (Def_Id, First_Index (T));
12383 Set_Is_Constrained (Def_Id, True);
12384 Set_Is_Aliased (Def_Id, Is_Aliased (T));
12385 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12387 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
12388 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
12390 -- A subtype does not inherit the Packed_Array_Impl_Type of is parent.
12391 -- We need to initialize the attribute because if Def_Id is previously
12392 -- analyzed through a limited_with clause, it will have the attributes
12393 -- of an incomplete type, one of which is an Elist that overlaps the
12394 -- Packed_Array_Impl_Type field.
12396 Set_Packed_Array_Impl_Type (Def_Id, Empty);
12398 -- Build a freeze node if parent still needs one. Also make sure that
12399 -- the Depends_On_Private status is set because the subtype will need
12400 -- reprocessing at the time the base type does, and also we must set a
12401 -- conditional delay.
12403 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
12404 Conditional_Delay (Def_Id, T);
12405 end Constrain_Array;
12407 ------------------------------
12408 -- Constrain_Component_Type --
12409 ------------------------------
12411 function Constrain_Component_Type
12413 Constrained_Typ : Entity_Id;
12414 Related_Node : Node_Id;
12416 Constraints : Elist_Id) return Entity_Id
12418 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
12419 Compon_Type : constant Entity_Id := Etype (Comp);
12421 function Build_Constrained_Array_Type
12422 (Old_Type : Entity_Id) return Entity_Id;
12423 -- If Old_Type is an array type, one of whose indexes is constrained
12424 -- by a discriminant, build an Itype whose constraint replaces the
12425 -- discriminant with its value in the constraint.
12427 function Build_Constrained_Discriminated_Type
12428 (Old_Type : Entity_Id) return Entity_Id;
12429 -- Ditto for record components
12431 function Build_Constrained_Access_Type
12432 (Old_Type : Entity_Id) return Entity_Id;
12433 -- Ditto for access types. Makes use of previous two functions, to
12434 -- constrain designated type.
12436 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
12437 -- T is an array or discriminated type, C is a list of constraints
12438 -- that apply to T. This routine builds the constrained subtype.
12440 function Is_Discriminant (Expr : Node_Id) return Boolean;
12441 -- Returns True if Expr is a discriminant
12443 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
12444 -- Find the value of discriminant Discrim in Constraint
12446 -----------------------------------
12447 -- Build_Constrained_Access_Type --
12448 -----------------------------------
12450 function Build_Constrained_Access_Type
12451 (Old_Type : Entity_Id) return Entity_Id
12453 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
12455 Desig_Subtype : Entity_Id;
12459 -- if the original access type was not embedded in the enclosing
12460 -- type definition, there is no need to produce a new access
12461 -- subtype. In fact every access type with an explicit constraint
12462 -- generates an itype whose scope is the enclosing record.
12464 if not Is_Type (Scope (Old_Type)) then
12467 elsif Is_Array_Type (Desig_Type) then
12468 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
12470 elsif Has_Discriminants (Desig_Type) then
12472 -- This may be an access type to an enclosing record type for
12473 -- which we are constructing the constrained components. Return
12474 -- the enclosing record subtype. This is not always correct,
12475 -- but avoids infinite recursion. ???
12477 Desig_Subtype := Any_Type;
12479 for J in reverse 0 .. Scope_Stack.Last loop
12480 Scop := Scope_Stack.Table (J).Entity;
12483 and then Base_Type (Scop) = Base_Type (Desig_Type)
12485 Desig_Subtype := Scop;
12488 exit when not Is_Type (Scop);
12491 if Desig_Subtype = Any_Type then
12493 Build_Constrained_Discriminated_Type (Desig_Type);
12500 if Desig_Subtype /= Desig_Type then
12502 -- The Related_Node better be here or else we won't be able
12503 -- to attach new itypes to a node in the tree.
12505 pragma Assert (Present (Related_Node));
12507 Itype := Create_Itype (E_Access_Subtype, Related_Node);
12509 Set_Etype (Itype, Base_Type (Old_Type));
12510 Set_Size_Info (Itype, (Old_Type));
12511 Set_Directly_Designated_Type (Itype, Desig_Subtype);
12512 Set_Depends_On_Private (Itype, Has_Private_Component
12514 Set_Is_Access_Constant (Itype, Is_Access_Constant
12517 -- The new itype needs freezing when it depends on a not frozen
12518 -- type and the enclosing subtype needs freezing.
12520 if Has_Delayed_Freeze (Constrained_Typ)
12521 and then not Is_Frozen (Constrained_Typ)
12523 Conditional_Delay (Itype, Base_Type (Old_Type));
12531 end Build_Constrained_Access_Type;
12533 ----------------------------------
12534 -- Build_Constrained_Array_Type --
12535 ----------------------------------
12537 function Build_Constrained_Array_Type
12538 (Old_Type : Entity_Id) return Entity_Id
12542 Old_Index : Node_Id;
12543 Range_Node : Node_Id;
12544 Constr_List : List_Id;
12546 Need_To_Create_Itype : Boolean := False;
12549 Old_Index := First_Index (Old_Type);
12550 while Present (Old_Index) loop
12551 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
12553 if Is_Discriminant (Lo_Expr)
12555 Is_Discriminant (Hi_Expr)
12557 Need_To_Create_Itype := True;
12560 Next_Index (Old_Index);
12563 if Need_To_Create_Itype then
12564 Constr_List := New_List;
12566 Old_Index := First_Index (Old_Type);
12567 while Present (Old_Index) loop
12568 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
12570 if Is_Discriminant (Lo_Expr) then
12571 Lo_Expr := Get_Discr_Value (Lo_Expr);
12574 if Is_Discriminant (Hi_Expr) then
12575 Hi_Expr := Get_Discr_Value (Hi_Expr);
12580 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
12582 Append (Range_Node, To => Constr_List);
12584 Next_Index (Old_Index);
12587 return Build_Subtype (Old_Type, Constr_List);
12592 end Build_Constrained_Array_Type;
12594 ------------------------------------------
12595 -- Build_Constrained_Discriminated_Type --
12596 ------------------------------------------
12598 function Build_Constrained_Discriminated_Type
12599 (Old_Type : Entity_Id) return Entity_Id
12602 Constr_List : List_Id;
12603 Old_Constraint : Elmt_Id;
12605 Need_To_Create_Itype : Boolean := False;
12608 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
12609 while Present (Old_Constraint) loop
12610 Expr := Node (Old_Constraint);
12612 if Is_Discriminant (Expr) then
12613 Need_To_Create_Itype := True;
12616 Next_Elmt (Old_Constraint);
12619 if Need_To_Create_Itype then
12620 Constr_List := New_List;
12622 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
12623 while Present (Old_Constraint) loop
12624 Expr := Node (Old_Constraint);
12626 if Is_Discriminant (Expr) then
12627 Expr := Get_Discr_Value (Expr);
12630 Append (New_Copy_Tree (Expr), To => Constr_List);
12632 Next_Elmt (Old_Constraint);
12635 return Build_Subtype (Old_Type, Constr_List);
12640 end Build_Constrained_Discriminated_Type;
12642 -------------------
12643 -- Build_Subtype --
12644 -------------------
12646 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
12648 Subtyp_Decl : Node_Id;
12649 Def_Id : Entity_Id;
12650 Btyp : Entity_Id := Base_Type (T);
12653 -- The Related_Node better be here or else we won't be able to
12654 -- attach new itypes to a node in the tree.
12656 pragma Assert (Present (Related_Node));
12658 -- If the view of the component's type is incomplete or private
12659 -- with unknown discriminants, then the constraint must be applied
12660 -- to the full type.
12662 if Has_Unknown_Discriminants (Btyp)
12663 and then Present (Underlying_Type (Btyp))
12665 Btyp := Underlying_Type (Btyp);
12669 Make_Subtype_Indication (Loc,
12670 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
12671 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
12673 Def_Id := Create_Itype (Ekind (T), Related_Node);
12676 Make_Subtype_Declaration (Loc,
12677 Defining_Identifier => Def_Id,
12678 Subtype_Indication => Indic);
12680 Set_Parent (Subtyp_Decl, Parent (Related_Node));
12682 -- Itypes must be analyzed with checks off (see package Itypes)
12684 Analyze (Subtyp_Decl, Suppress => All_Checks);
12689 ---------------------
12690 -- Get_Discr_Value --
12691 ---------------------
12693 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
12698 -- The discriminant may be declared for the type, in which case we
12699 -- find it by iterating over the list of discriminants. If the
12700 -- discriminant is inherited from a parent type, it appears as the
12701 -- corresponding discriminant of the current type. This will be the
12702 -- case when constraining an inherited component whose constraint is
12703 -- given by a discriminant of the parent.
12705 D := First_Discriminant (Typ);
12706 E := First_Elmt (Constraints);
12708 while Present (D) loop
12709 if D = Entity (Discrim)
12710 or else D = CR_Discriminant (Entity (Discrim))
12711 or else Corresponding_Discriminant (D) = Entity (Discrim)
12716 Next_Discriminant (D);
12720 -- The Corresponding_Discriminant mechanism is incomplete, because
12721 -- the correspondence between new and old discriminants is not one
12722 -- to one: one new discriminant can constrain several old ones. In
12723 -- that case, scan sequentially the stored_constraint, the list of
12724 -- discriminants of the parents, and the constraints.
12726 -- Previous code checked for the present of the Stored_Constraint
12727 -- list for the derived type, but did not use it at all. Should it
12728 -- be present when the component is a discriminated task type?
12730 if Is_Derived_Type (Typ)
12731 and then Scope (Entity (Discrim)) = Etype (Typ)
12733 D := First_Discriminant (Etype (Typ));
12734 E := First_Elmt (Constraints);
12735 while Present (D) loop
12736 if D = Entity (Discrim) then
12740 Next_Discriminant (D);
12745 -- Something is wrong if we did not find the value
12747 raise Program_Error;
12748 end Get_Discr_Value;
12750 ---------------------
12751 -- Is_Discriminant --
12752 ---------------------
12754 function Is_Discriminant (Expr : Node_Id) return Boolean is
12755 Discrim_Scope : Entity_Id;
12758 if Denotes_Discriminant (Expr) then
12759 Discrim_Scope := Scope (Entity (Expr));
12761 -- Either we have a reference to one of Typ's discriminants,
12763 pragma Assert (Discrim_Scope = Typ
12765 -- or to the discriminants of the parent type, in the case
12766 -- of a derivation of a tagged type with variants.
12768 or else Discrim_Scope = Etype (Typ)
12769 or else Full_View (Discrim_Scope) = Etype (Typ)
12771 -- or same as above for the case where the discriminants
12772 -- were declared in Typ's private view.
12774 or else (Is_Private_Type (Discrim_Scope)
12775 and then Chars (Discrim_Scope) = Chars (Typ))
12777 -- or else we are deriving from the full view and the
12778 -- discriminant is declared in the private entity.
12780 or else (Is_Private_Type (Typ)
12781 and then Chars (Discrim_Scope) = Chars (Typ))
12783 -- Or we are constrained the corresponding record of a
12784 -- synchronized type that completes a private declaration.
12786 or else (Is_Concurrent_Record_Type (Typ)
12788 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
12790 -- or we have a class-wide type, in which case make sure the
12791 -- discriminant found belongs to the root type.
12793 or else (Is_Class_Wide_Type (Typ)
12794 and then Etype (Typ) = Discrim_Scope));
12799 -- In all other cases we have something wrong
12802 end Is_Discriminant;
12804 -- Start of processing for Constrain_Component_Type
12807 if Nkind (Parent (Comp)) = N_Component_Declaration
12808 and then Comes_From_Source (Parent (Comp))
12809 and then Comes_From_Source
12810 (Subtype_Indication (Component_Definition (Parent (Comp))))
12813 (Subtype_Indication (Component_Definition (Parent (Comp))))
12815 return Compon_Type;
12817 elsif Is_Array_Type (Compon_Type) then
12818 return Build_Constrained_Array_Type (Compon_Type);
12820 elsif Has_Discriminants (Compon_Type) then
12821 return Build_Constrained_Discriminated_Type (Compon_Type);
12823 elsif Is_Access_Type (Compon_Type) then
12824 return Build_Constrained_Access_Type (Compon_Type);
12827 return Compon_Type;
12829 end Constrain_Component_Type;
12831 --------------------------
12832 -- Constrain_Concurrent --
12833 --------------------------
12835 -- For concurrent types, the associated record value type carries the same
12836 -- discriminants, so when we constrain a concurrent type, we must constrain
12837 -- the corresponding record type as well.
12839 procedure Constrain_Concurrent
12840 (Def_Id : in out Entity_Id;
12842 Related_Nod : Node_Id;
12843 Related_Id : Entity_Id;
12844 Suffix : Character)
12846 -- Retrieve Base_Type to ensure getting to the concurrent type in the
12847 -- case of a private subtype (needed when only doing semantic analysis).
12849 T_Ent : Entity_Id := Base_Type (Entity (Subtype_Mark (SI)));
12853 if Is_Access_Type (T_Ent) then
12854 T_Ent := Designated_Type (T_Ent);
12857 T_Val := Corresponding_Record_Type (T_Ent);
12859 if Present (T_Val) then
12861 if No (Def_Id) then
12862 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
12864 -- Elaborate itype now, as it may be used in a subsequent
12865 -- synchronized operation in another scope.
12867 if Nkind (Related_Nod) = N_Full_Type_Declaration then
12868 Build_Itype_Reference (Def_Id, Related_Nod);
12872 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
12874 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12875 Set_Corresponding_Record_Type (Def_Id,
12876 Constrain_Corresponding_Record (Def_Id, T_Val, Related_Nod));
12879 -- If there is no associated record, expansion is disabled and this
12880 -- is a generic context. Create a subtype in any case, so that
12881 -- semantic analysis can proceed.
12883 if No (Def_Id) then
12884 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
12887 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
12889 end Constrain_Concurrent;
12891 ------------------------------------
12892 -- Constrain_Corresponding_Record --
12893 ------------------------------------
12895 function Constrain_Corresponding_Record
12896 (Prot_Subt : Entity_Id;
12897 Corr_Rec : Entity_Id;
12898 Related_Nod : Node_Id) return Entity_Id
12900 T_Sub : constant Entity_Id :=
12901 Create_Itype (E_Record_Subtype, Related_Nod, Corr_Rec, 'C');
12904 Set_Etype (T_Sub, Corr_Rec);
12905 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
12906 Set_Is_Constrained (T_Sub, True);
12907 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
12908 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
12910 if Has_Discriminants (Prot_Subt) then -- False only if errors.
12911 Set_Discriminant_Constraint
12912 (T_Sub, Discriminant_Constraint (Prot_Subt));
12913 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
12914 Create_Constrained_Components
12915 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
12918 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
12920 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
12921 Conditional_Delay (T_Sub, Corr_Rec);
12924 -- This is a component subtype: it will be frozen in the context of
12925 -- the enclosing record's init_proc, so that discriminant references
12926 -- are resolved to discriminals. (Note: we used to skip freezing
12927 -- altogether in that case, which caused errors downstream for
12928 -- components of a bit packed array type).
12930 Set_Has_Delayed_Freeze (T_Sub);
12934 end Constrain_Corresponding_Record;
12936 -----------------------
12937 -- Constrain_Decimal --
12938 -----------------------
12940 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
12941 T : constant Entity_Id := Entity (Subtype_Mark (S));
12942 C : constant Node_Id := Constraint (S);
12943 Loc : constant Source_Ptr := Sloc (C);
12944 Range_Expr : Node_Id;
12945 Digits_Expr : Node_Id;
12950 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
12952 if Nkind (C) = N_Range_Constraint then
12953 Range_Expr := Range_Expression (C);
12954 Digits_Val := Digits_Value (T);
12957 pragma Assert (Nkind (C) = N_Digits_Constraint);
12959 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
12961 Digits_Expr := Digits_Expression (C);
12962 Analyze_And_Resolve (Digits_Expr, Any_Integer);
12964 Check_Digits_Expression (Digits_Expr);
12965 Digits_Val := Expr_Value (Digits_Expr);
12967 if Digits_Val > Digits_Value (T) then
12969 ("digits expression is incompatible with subtype", C);
12970 Digits_Val := Digits_Value (T);
12973 if Present (Range_Constraint (C)) then
12974 Range_Expr := Range_Expression (Range_Constraint (C));
12976 Range_Expr := Empty;
12980 Set_Etype (Def_Id, Base_Type (T));
12981 Set_Size_Info (Def_Id, (T));
12982 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12983 Set_Delta_Value (Def_Id, Delta_Value (T));
12984 Set_Scale_Value (Def_Id, Scale_Value (T));
12985 Set_Small_Value (Def_Id, Small_Value (T));
12986 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
12987 Set_Digits_Value (Def_Id, Digits_Val);
12989 -- Manufacture range from given digits value if no range present
12991 if No (Range_Expr) then
12992 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
12996 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
12998 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
13001 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
13002 Set_Discrete_RM_Size (Def_Id);
13004 -- Unconditionally delay the freeze, since we cannot set size
13005 -- information in all cases correctly until the freeze point.
13007 Set_Has_Delayed_Freeze (Def_Id);
13008 end Constrain_Decimal;
13010 ----------------------------------
13011 -- Constrain_Discriminated_Type --
13012 ----------------------------------
13014 procedure Constrain_Discriminated_Type
13015 (Def_Id : Entity_Id;
13017 Related_Nod : Node_Id;
13018 For_Access : Boolean := False)
13020 E : constant Entity_Id := Entity (Subtype_Mark (S));
13023 Elist : Elist_Id := New_Elmt_List;
13025 procedure Fixup_Bad_Constraint;
13026 -- This is called after finding a bad constraint, and after having
13027 -- posted an appropriate error message. The mission is to leave the
13028 -- entity T in as reasonable state as possible.
13030 --------------------------
13031 -- Fixup_Bad_Constraint --
13032 --------------------------
13034 procedure Fixup_Bad_Constraint is
13036 -- Set a reasonable Ekind for the entity. For an incomplete type,
13037 -- we can't do much, but for other types, we can set the proper
13038 -- corresponding subtype kind.
13040 if Ekind (T) = E_Incomplete_Type then
13041 Set_Ekind (Def_Id, Ekind (T));
13043 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
13046 -- Set Etype to the known type, to reduce chances of cascaded errors
13048 Set_Etype (Def_Id, E);
13049 Set_Error_Posted (Def_Id);
13050 end Fixup_Bad_Constraint;
13052 -- Start of processing for Constrain_Discriminated_Type
13055 C := Constraint (S);
13057 -- A discriminant constraint is only allowed in a subtype indication,
13058 -- after a subtype mark. This subtype mark must denote either a type
13059 -- with discriminants, or an access type whose designated type is a
13060 -- type with discriminants. A discriminant constraint specifies the
13061 -- values of these discriminants (RM 3.7.2(5)).
13063 T := Base_Type (Entity (Subtype_Mark (S)));
13065 if Is_Access_Type (T) then
13066 T := Designated_Type (T);
13069 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal.
13070 -- Avoid generating an error for access-to-incomplete subtypes.
13072 if Ada_Version >= Ada_2005
13073 and then Ekind (T) = E_Incomplete_Type
13074 and then Nkind (Parent (S)) = N_Subtype_Declaration
13075 and then not Is_Itype (Def_Id)
13077 -- A little sanity check, emit an error message if the type
13078 -- has discriminants to begin with. Type T may be a regular
13079 -- incomplete type or imported via a limited with clause.
13081 if Has_Discriminants (T)
13082 or else (From_Limited_With (T)
13083 and then Present (Non_Limited_View (T))
13084 and then Nkind (Parent (Non_Limited_View (T))) =
13085 N_Full_Type_Declaration
13086 and then Present (Discriminant_Specifications
13087 (Parent (Non_Limited_View (T)))))
13090 ("(Ada 2005) incomplete subtype may not be constrained", C);
13092 Error_Msg_N ("invalid constraint: type has no discriminant", C);
13095 Fixup_Bad_Constraint;
13098 -- Check that the type has visible discriminants. The type may be
13099 -- a private type with unknown discriminants whose full view has
13100 -- discriminants which are invisible.
13102 elsif not Has_Discriminants (T)
13104 (Has_Unknown_Discriminants (T)
13105 and then Is_Private_Type (T))
13107 Error_Msg_N ("invalid constraint: type has no discriminant", C);
13108 Fixup_Bad_Constraint;
13111 elsif Is_Constrained (E)
13112 or else (Ekind (E) = E_Class_Wide_Subtype
13113 and then Present (Discriminant_Constraint (E)))
13115 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
13116 Fixup_Bad_Constraint;
13120 -- T may be an unconstrained subtype (e.g. a generic actual).
13121 -- Constraint applies to the base type.
13123 T := Base_Type (T);
13125 Elist := Build_Discriminant_Constraints (T, S);
13127 -- If the list returned was empty we had an error in building the
13128 -- discriminant constraint. We have also already signalled an error
13129 -- in the incomplete type case
13131 if Is_Empty_Elmt_List (Elist) then
13132 Fixup_Bad_Constraint;
13136 Build_Discriminated_Subtype (T, Def_Id, Elist, Related_Nod, For_Access);
13137 end Constrain_Discriminated_Type;
13139 ---------------------------
13140 -- Constrain_Enumeration --
13141 ---------------------------
13143 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
13144 T : constant Entity_Id := Entity (Subtype_Mark (S));
13145 C : constant Node_Id := Constraint (S);
13148 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13150 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
13152 Set_Etype (Def_Id, Base_Type (T));
13153 Set_Size_Info (Def_Id, (T));
13154 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13155 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13157 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13159 Set_Discrete_RM_Size (Def_Id);
13160 end Constrain_Enumeration;
13162 ----------------------
13163 -- Constrain_Float --
13164 ----------------------
13166 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
13167 T : constant Entity_Id := Entity (Subtype_Mark (S));
13173 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
13175 Set_Etype (Def_Id, Base_Type (T));
13176 Set_Size_Info (Def_Id, (T));
13177 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13179 -- Process the constraint
13181 C := Constraint (S);
13183 -- Digits constraint present
13185 if Nkind (C) = N_Digits_Constraint then
13187 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
13188 Check_Restriction (No_Obsolescent_Features, C);
13190 if Warn_On_Obsolescent_Feature then
13192 ("subtype digits constraint is an " &
13193 "obsolescent feature (RM J.3(8))?j?", C);
13196 D := Digits_Expression (C);
13197 Analyze_And_Resolve (D, Any_Integer);
13198 Check_Digits_Expression (D);
13199 Set_Digits_Value (Def_Id, Expr_Value (D));
13201 -- Check that digits value is in range. Obviously we can do this
13202 -- at compile time, but it is strictly a runtime check, and of
13203 -- course there is an ACVC test that checks this.
13205 if Digits_Value (Def_Id) > Digits_Value (T) then
13206 Error_Msg_Uint_1 := Digits_Value (T);
13207 Error_Msg_N ("??digits value is too large, maximum is ^", D);
13209 Make_Raise_Constraint_Error (Sloc (D),
13210 Reason => CE_Range_Check_Failed);
13211 Insert_Action (Declaration_Node (Def_Id), Rais);
13214 C := Range_Constraint (C);
13216 -- No digits constraint present
13219 Set_Digits_Value (Def_Id, Digits_Value (T));
13222 -- Range constraint present
13224 if Nkind (C) = N_Range_Constraint then
13225 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13227 -- No range constraint present
13230 pragma Assert (No (C));
13231 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13234 Set_Is_Constrained (Def_Id);
13235 end Constrain_Float;
13237 ---------------------
13238 -- Constrain_Index --
13239 ---------------------
13241 procedure Constrain_Index
13244 Related_Nod : Node_Id;
13245 Related_Id : Entity_Id;
13246 Suffix : Character;
13247 Suffix_Index : Nat)
13249 Def_Id : Entity_Id;
13250 R : Node_Id := Empty;
13251 T : constant Entity_Id := Etype (Index);
13255 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
13256 Set_Etype (Def_Id, Base_Type (T));
13258 if Nkind (S) = N_Range
13260 (Nkind (S) = N_Attribute_Reference
13261 and then Attribute_Name (S) = Name_Range)
13263 -- A Range attribute will be transformed into N_Range by Resolve
13269 Process_Range_Expr_In_Decl (R, T);
13271 if not Error_Posted (S)
13273 (Nkind (S) /= N_Range
13274 or else not Covers (T, (Etype (Low_Bound (S))))
13275 or else not Covers (T, (Etype (High_Bound (S)))))
13277 if Base_Type (T) /= Any_Type
13278 and then Etype (Low_Bound (S)) /= Any_Type
13279 and then Etype (High_Bound (S)) /= Any_Type
13281 Error_Msg_N ("range expected", S);
13285 elsif Nkind (S) = N_Subtype_Indication then
13287 -- The parser has verified that this is a discrete indication
13289 Resolve_Discrete_Subtype_Indication (S, T);
13290 Bad_Predicated_Subtype_Use
13291 ("subtype& has predicate, not allowed in index constraint",
13292 S, Entity (Subtype_Mark (S)));
13294 R := Range_Expression (Constraint (S));
13296 -- Capture values of bounds and generate temporaries for them if
13297 -- needed, since checks may cause duplication of the expressions
13298 -- which must not be reevaluated.
13300 -- The forced evaluation removes side effects from expressions, which
13301 -- should occur also in GNATprove mode. Otherwise, we end up with
13302 -- unexpected insertions of actions at places where this is not
13303 -- supposed to occur, e.g. on default parameters of a call.
13305 if Expander_Active or GNATprove_Mode then
13307 (Low_Bound (R), Related_Id => Def_Id, Is_Low_Bound => True);
13309 (High_Bound (R), Related_Id => Def_Id, Is_High_Bound => True);
13312 elsif Nkind (S) = N_Discriminant_Association then
13314 -- Syntactically valid in subtype indication
13316 Error_Msg_N ("invalid index constraint", S);
13317 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13320 -- Subtype_Mark case, no anonymous subtypes to construct
13325 if Is_Entity_Name (S) then
13326 if not Is_Type (Entity (S)) then
13327 Error_Msg_N ("expect subtype mark for index constraint", S);
13329 elsif Base_Type (Entity (S)) /= Base_Type (T) then
13330 Wrong_Type (S, Base_Type (T));
13332 -- Check error of subtype with predicate in index constraint
13335 Bad_Predicated_Subtype_Use
13336 ("subtype& has predicate, not allowed in index constraint",
13343 Error_Msg_N ("invalid index constraint", S);
13344 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13349 -- Complete construction of the Itype
13351 if Is_Modular_Integer_Type (T) then
13352 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13354 elsif Is_Integer_Type (T) then
13355 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13358 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13359 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13360 Set_First_Literal (Def_Id, First_Literal (T));
13363 Set_Size_Info (Def_Id, (T));
13364 Set_RM_Size (Def_Id, RM_Size (T));
13365 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13367 Set_Scalar_Range (Def_Id, R);
13369 Set_Etype (S, Def_Id);
13370 Set_Discrete_RM_Size (Def_Id);
13371 end Constrain_Index;
13373 -----------------------
13374 -- Constrain_Integer --
13375 -----------------------
13377 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
13378 T : constant Entity_Id := Entity (Subtype_Mark (S));
13379 C : constant Node_Id := Constraint (S);
13382 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13384 if Is_Modular_Integer_Type (T) then
13385 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13387 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13390 Set_Etype (Def_Id, Base_Type (T));
13391 Set_Size_Info (Def_Id, (T));
13392 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13393 Set_Discrete_RM_Size (Def_Id);
13394 end Constrain_Integer;
13396 ------------------------------
13397 -- Constrain_Ordinary_Fixed --
13398 ------------------------------
13400 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
13401 T : constant Entity_Id := Entity (Subtype_Mark (S));
13407 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
13408 Set_Etype (Def_Id, Base_Type (T));
13409 Set_Size_Info (Def_Id, (T));
13410 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13411 Set_Small_Value (Def_Id, Small_Value (T));
13413 -- Process the constraint
13415 C := Constraint (S);
13417 -- Delta constraint present
13419 if Nkind (C) = N_Delta_Constraint then
13421 Check_SPARK_05_Restriction ("delta constraint is not allowed", S);
13422 Check_Restriction (No_Obsolescent_Features, C);
13424 if Warn_On_Obsolescent_Feature then
13426 ("subtype delta constraint is an " &
13427 "obsolescent feature (RM J.3(7))?j?");
13430 D := Delta_Expression (C);
13431 Analyze_And_Resolve (D, Any_Real);
13432 Check_Delta_Expression (D);
13433 Set_Delta_Value (Def_Id, Expr_Value_R (D));
13435 -- Check that delta value is in range. Obviously we can do this
13436 -- at compile time, but it is strictly a runtime check, and of
13437 -- course there is an ACVC test that checks this.
13439 if Delta_Value (Def_Id) < Delta_Value (T) then
13440 Error_Msg_N ("??delta value is too small", D);
13442 Make_Raise_Constraint_Error (Sloc (D),
13443 Reason => CE_Range_Check_Failed);
13444 Insert_Action (Declaration_Node (Def_Id), Rais);
13447 C := Range_Constraint (C);
13449 -- No delta constraint present
13452 Set_Delta_Value (Def_Id, Delta_Value (T));
13455 -- Range constraint present
13457 if Nkind (C) = N_Range_Constraint then
13458 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13460 -- No range constraint present
13463 pragma Assert (No (C));
13464 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13467 Set_Discrete_RM_Size (Def_Id);
13469 -- Unconditionally delay the freeze, since we cannot set size
13470 -- information in all cases correctly until the freeze point.
13472 Set_Has_Delayed_Freeze (Def_Id);
13473 end Constrain_Ordinary_Fixed;
13475 -----------------------
13476 -- Contain_Interface --
13477 -----------------------
13479 function Contain_Interface
13480 (Iface : Entity_Id;
13481 Ifaces : Elist_Id) return Boolean
13483 Iface_Elmt : Elmt_Id;
13486 if Present (Ifaces) then
13487 Iface_Elmt := First_Elmt (Ifaces);
13488 while Present (Iface_Elmt) loop
13489 if Node (Iface_Elmt) = Iface then
13493 Next_Elmt (Iface_Elmt);
13498 end Contain_Interface;
13500 ---------------------------
13501 -- Convert_Scalar_Bounds --
13502 ---------------------------
13504 procedure Convert_Scalar_Bounds
13506 Parent_Type : Entity_Id;
13507 Derived_Type : Entity_Id;
13510 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
13517 -- Defend against previous errors
13519 if No (Scalar_Range (Derived_Type)) then
13520 Check_Error_Detected;
13524 Lo := Build_Scalar_Bound
13525 (Type_Low_Bound (Derived_Type),
13526 Parent_Type, Implicit_Base);
13528 Hi := Build_Scalar_Bound
13529 (Type_High_Bound (Derived_Type),
13530 Parent_Type, Implicit_Base);
13537 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
13539 Set_Parent (Rng, N);
13540 Set_Scalar_Range (Derived_Type, Rng);
13542 -- Analyze the bounds
13544 Analyze_And_Resolve (Lo, Implicit_Base);
13545 Analyze_And_Resolve (Hi, Implicit_Base);
13547 -- Analyze the range itself, except that we do not analyze it if
13548 -- the bounds are real literals, and we have a fixed-point type.
13549 -- The reason for this is that we delay setting the bounds in this
13550 -- case till we know the final Small and Size values (see circuit
13551 -- in Freeze.Freeze_Fixed_Point_Type for further details).
13553 if Is_Fixed_Point_Type (Parent_Type)
13554 and then Nkind (Lo) = N_Real_Literal
13555 and then Nkind (Hi) = N_Real_Literal
13559 -- Here we do the analysis of the range
13561 -- Note: we do this manually, since if we do a normal Analyze and
13562 -- Resolve call, there are problems with the conversions used for
13563 -- the derived type range.
13566 Set_Etype (Rng, Implicit_Base);
13567 Set_Analyzed (Rng, True);
13569 end Convert_Scalar_Bounds;
13571 -------------------
13572 -- Copy_And_Swap --
13573 -------------------
13575 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
13577 -- Initialize new full declaration entity by copying the pertinent
13578 -- fields of the corresponding private declaration entity.
13580 -- We temporarily set Ekind to a value appropriate for a type to
13581 -- avoid assert failures in Einfo from checking for setting type
13582 -- attributes on something that is not a type. Ekind (Priv) is an
13583 -- appropriate choice, since it allowed the attributes to be set
13584 -- in the first place. This Ekind value will be modified later.
13586 Set_Ekind (Full, Ekind (Priv));
13588 -- Also set Etype temporarily to Any_Type, again, in the absence
13589 -- of errors, it will be properly reset, and if there are errors,
13590 -- then we want a value of Any_Type to remain.
13592 Set_Etype (Full, Any_Type);
13594 -- Now start copying attributes
13596 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
13598 if Has_Discriminants (Full) then
13599 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
13600 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
13603 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
13604 Set_Homonym (Full, Homonym (Priv));
13605 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
13606 Set_Is_Public (Full, Is_Public (Priv));
13607 Set_Is_Pure (Full, Is_Pure (Priv));
13608 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
13609 Set_Has_Pragma_Unmodified (Full, Has_Pragma_Unmodified (Priv));
13610 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
13611 Set_Has_Pragma_Unreferenced_Objects
13612 (Full, Has_Pragma_Unreferenced_Objects
13615 Conditional_Delay (Full, Priv);
13617 if Is_Tagged_Type (Full) then
13618 Set_Direct_Primitive_Operations
13619 (Full, Direct_Primitive_Operations (Priv));
13620 Set_No_Tagged_Streams_Pragma
13621 (Full, No_Tagged_Streams_Pragma (Priv));
13623 if Is_Base_Type (Priv) then
13624 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
13628 Set_Is_Volatile (Full, Is_Volatile (Priv));
13629 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
13630 Set_Scope (Full, Scope (Priv));
13631 Set_Next_Entity (Full, Next_Entity (Priv));
13632 Set_First_Entity (Full, First_Entity (Priv));
13633 Set_Last_Entity (Full, Last_Entity (Priv));
13635 -- If access types have been recorded for later handling, keep them in
13636 -- the full view so that they get handled when the full view freeze
13637 -- node is expanded.
13639 if Present (Freeze_Node (Priv))
13640 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
13642 Ensure_Freeze_Node (Full);
13643 Set_Access_Types_To_Process
13644 (Freeze_Node (Full),
13645 Access_Types_To_Process (Freeze_Node (Priv)));
13648 -- Swap the two entities. Now Private is the full type entity and Full
13649 -- is the private one. They will be swapped back at the end of the
13650 -- private part. This swapping ensures that the entity that is visible
13651 -- in the private part is the full declaration.
13653 Exchange_Entities (Priv, Full);
13654 Append_Entity (Full, Scope (Full));
13657 -------------------------------------
13658 -- Copy_Array_Base_Type_Attributes --
13659 -------------------------------------
13661 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
13663 Set_Component_Alignment (T1, Component_Alignment (T2));
13664 Set_Component_Type (T1, Component_Type (T2));
13665 Set_Component_Size (T1, Component_Size (T2));
13666 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
13667 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
13668 Set_Has_Protected (T1, Has_Protected (T2));
13669 Set_Has_Task (T1, Has_Task (T2));
13670 Set_Is_Packed (T1, Is_Packed (T2));
13671 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
13672 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
13673 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
13674 end Copy_Array_Base_Type_Attributes;
13676 -----------------------------------
13677 -- Copy_Array_Subtype_Attributes --
13678 -----------------------------------
13680 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
13682 Set_Size_Info (T1, T2);
13684 Set_First_Index (T1, First_Index (T2));
13685 Set_Is_Aliased (T1, Is_Aliased (T2));
13686 Set_Is_Volatile (T1, Is_Volatile (T2));
13687 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
13688 Set_Is_Constrained (T1, Is_Constrained (T2));
13689 Set_Depends_On_Private (T1, Has_Private_Component (T2));
13690 Inherit_Rep_Item_Chain (T1, T2);
13691 Set_Convention (T1, Convention (T2));
13692 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
13693 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
13694 Set_Packed_Array_Impl_Type (T1, Packed_Array_Impl_Type (T2));
13695 end Copy_Array_Subtype_Attributes;
13697 -----------------------------------
13698 -- Create_Constrained_Components --
13699 -----------------------------------
13701 procedure Create_Constrained_Components
13703 Decl_Node : Node_Id;
13705 Constraints : Elist_Id)
13707 Loc : constant Source_Ptr := Sloc (Subt);
13708 Comp_List : constant Elist_Id := New_Elmt_List;
13709 Parent_Type : constant Entity_Id := Etype (Typ);
13710 Assoc_List : constant List_Id := New_List;
13711 Discr_Val : Elmt_Id;
13715 Is_Static : Boolean := True;
13717 procedure Collect_Fixed_Components (Typ : Entity_Id);
13718 -- Collect parent type components that do not appear in a variant part
13720 procedure Create_All_Components;
13721 -- Iterate over Comp_List to create the components of the subtype
13723 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
13724 -- Creates a new component from Old_Compon, copying all the fields from
13725 -- it, including its Etype, inserts the new component in the Subt entity
13726 -- chain and returns the new component.
13728 function Is_Variant_Record (T : Entity_Id) return Boolean;
13729 -- If true, and discriminants are static, collect only components from
13730 -- variants selected by discriminant values.
13732 ------------------------------
13733 -- Collect_Fixed_Components --
13734 ------------------------------
13736 procedure Collect_Fixed_Components (Typ : Entity_Id) is
13738 -- Build association list for discriminants, and find components of the
13739 -- variant part selected by the values of the discriminants.
13741 Old_C := First_Discriminant (Typ);
13742 Discr_Val := First_Elmt (Constraints);
13743 while Present (Old_C) loop
13744 Append_To (Assoc_List,
13745 Make_Component_Association (Loc,
13746 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
13747 Expression => New_Copy (Node (Discr_Val))));
13749 Next_Elmt (Discr_Val);
13750 Next_Discriminant (Old_C);
13753 -- The tag and the possible parent component are unconditionally in
13756 if Is_Tagged_Type (Typ) or else Has_Controlled_Component (Typ) then
13757 Old_C := First_Component (Typ);
13758 while Present (Old_C) loop
13759 if Nam_In (Chars (Old_C), Name_uTag, Name_uParent) then
13760 Append_Elmt (Old_C, Comp_List);
13763 Next_Component (Old_C);
13766 end Collect_Fixed_Components;
13768 ---------------------------
13769 -- Create_All_Components --
13770 ---------------------------
13772 procedure Create_All_Components is
13776 Comp := First_Elmt (Comp_List);
13777 while Present (Comp) loop
13778 Old_C := Node (Comp);
13779 New_C := Create_Component (Old_C);
13783 Constrain_Component_Type
13784 (Old_C, Subt, Decl_Node, Typ, Constraints));
13785 Set_Is_Public (New_C, Is_Public (Subt));
13789 end Create_All_Components;
13791 ----------------------
13792 -- Create_Component --
13793 ----------------------
13795 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
13796 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
13799 if Ekind (Old_Compon) = E_Discriminant
13800 and then Is_Completely_Hidden (Old_Compon)
13802 -- This is a shadow discriminant created for a discriminant of
13803 -- the parent type, which needs to be present in the subtype.
13804 -- Give the shadow discriminant an internal name that cannot
13805 -- conflict with that of visible components.
13807 Set_Chars (New_Compon, New_Internal_Name ('C'));
13810 -- Set the parent so we have a proper link for freezing etc. This is
13811 -- not a real parent pointer, since of course our parent does not own
13812 -- up to us and reference us, we are an illegitimate child of the
13813 -- original parent.
13815 Set_Parent (New_Compon, Parent (Old_Compon));
13817 -- If the old component's Esize was already determined and is a
13818 -- static value, then the new component simply inherits it. Otherwise
13819 -- the old component's size may require run-time determination, but
13820 -- the new component's size still might be statically determinable
13821 -- (if, for example it has a static constraint). In that case we want
13822 -- Layout_Type to recompute the component's size, so we reset its
13823 -- size and positional fields.
13825 if Frontend_Layout_On_Target
13826 and then not Known_Static_Esize (Old_Compon)
13828 Set_Esize (New_Compon, Uint_0);
13829 Init_Normalized_First_Bit (New_Compon);
13830 Init_Normalized_Position (New_Compon);
13831 Init_Normalized_Position_Max (New_Compon);
13834 -- We do not want this node marked as Comes_From_Source, since
13835 -- otherwise it would get first class status and a separate cross-
13836 -- reference line would be generated. Illegitimate children do not
13837 -- rate such recognition.
13839 Set_Comes_From_Source (New_Compon, False);
13841 -- But it is a real entity, and a birth certificate must be properly
13842 -- registered by entering it into the entity list.
13844 Enter_Name (New_Compon);
13847 end Create_Component;
13849 -----------------------
13850 -- Is_Variant_Record --
13851 -----------------------
13853 function Is_Variant_Record (T : Entity_Id) return Boolean is
13855 return Nkind (Parent (T)) = N_Full_Type_Declaration
13856 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
13857 and then Present (Component_List (Type_Definition (Parent (T))))
13860 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
13861 end Is_Variant_Record;
13863 -- Start of processing for Create_Constrained_Components
13866 pragma Assert (Subt /= Base_Type (Subt));
13867 pragma Assert (Typ = Base_Type (Typ));
13869 Set_First_Entity (Subt, Empty);
13870 Set_Last_Entity (Subt, Empty);
13872 -- Check whether constraint is fully static, in which case we can
13873 -- optimize the list of components.
13875 Discr_Val := First_Elmt (Constraints);
13876 while Present (Discr_Val) loop
13877 if not Is_OK_Static_Expression (Node (Discr_Val)) then
13878 Is_Static := False;
13882 Next_Elmt (Discr_Val);
13885 Set_Has_Static_Discriminants (Subt, Is_Static);
13889 -- Inherit the discriminants of the parent type
13891 Add_Discriminants : declare
13897 Old_C := First_Discriminant (Typ);
13899 while Present (Old_C) loop
13900 Num_Disc := Num_Disc + 1;
13901 New_C := Create_Component (Old_C);
13902 Set_Is_Public (New_C, Is_Public (Subt));
13903 Next_Discriminant (Old_C);
13906 -- For an untagged derived subtype, the number of discriminants may
13907 -- be smaller than the number of inherited discriminants, because
13908 -- several of them may be renamed by a single new discriminant or
13909 -- constrained. In this case, add the hidden discriminants back into
13910 -- the subtype, because they need to be present if the optimizer of
13911 -- the GCC 4.x back-end decides to break apart assignments between
13912 -- objects using the parent view into member-wise assignments.
13916 if Is_Derived_Type (Typ)
13917 and then not Is_Tagged_Type (Typ)
13919 Old_C := First_Stored_Discriminant (Typ);
13921 while Present (Old_C) loop
13922 Num_Gird := Num_Gird + 1;
13923 Next_Stored_Discriminant (Old_C);
13927 if Num_Gird > Num_Disc then
13929 -- Find out multiple uses of new discriminants, and add hidden
13930 -- components for the extra renamed discriminants. We recognize
13931 -- multiple uses through the Corresponding_Discriminant of a
13932 -- new discriminant: if it constrains several old discriminants,
13933 -- this field points to the last one in the parent type. The
13934 -- stored discriminants of the derived type have the same name
13935 -- as those of the parent.
13939 New_Discr : Entity_Id;
13940 Old_Discr : Entity_Id;
13943 Constr := First_Elmt (Stored_Constraint (Typ));
13944 Old_Discr := First_Stored_Discriminant (Typ);
13945 while Present (Constr) loop
13946 if Is_Entity_Name (Node (Constr))
13947 and then Ekind (Entity (Node (Constr))) = E_Discriminant
13949 New_Discr := Entity (Node (Constr));
13951 if Chars (Corresponding_Discriminant (New_Discr)) /=
13954 -- The new discriminant has been used to rename a
13955 -- subsequent old discriminant. Introduce a shadow
13956 -- component for the current old discriminant.
13958 New_C := Create_Component (Old_Discr);
13959 Set_Original_Record_Component (New_C, Old_Discr);
13963 -- The constraint has eliminated the old discriminant.
13964 -- Introduce a shadow component.
13966 New_C := Create_Component (Old_Discr);
13967 Set_Original_Record_Component (New_C, Old_Discr);
13970 Next_Elmt (Constr);
13971 Next_Stored_Discriminant (Old_Discr);
13975 end Add_Discriminants;
13978 and then Is_Variant_Record (Typ)
13980 Collect_Fixed_Components (Typ);
13982 Gather_Components (
13984 Component_List (Type_Definition (Parent (Typ))),
13985 Governed_By => Assoc_List,
13987 Report_Errors => Errors);
13988 pragma Assert (not Errors);
13990 Create_All_Components;
13992 -- If the subtype declaration is created for a tagged type derivation
13993 -- with constraints, we retrieve the record definition of the parent
13994 -- type to select the components of the proper variant.
13997 and then Is_Tagged_Type (Typ)
13998 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
14000 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
14001 and then Is_Variant_Record (Parent_Type)
14003 Collect_Fixed_Components (Typ);
14007 Component_List (Type_Definition (Parent (Parent_Type))),
14008 Governed_By => Assoc_List,
14010 Report_Errors => Errors);
14012 -- Note: previously there was a check at this point that no errors
14013 -- were detected. As a consequence of AI05-220 there may be an error
14014 -- if an inherited discriminant that controls a variant has a non-
14015 -- static constraint.
14017 -- If the tagged derivation has a type extension, collect all the
14018 -- new components therein.
14020 if Present (Record_Extension_Part (Type_Definition (Parent (Typ))))
14022 Old_C := First_Component (Typ);
14023 while Present (Old_C) loop
14024 if Original_Record_Component (Old_C) = Old_C
14025 and then Chars (Old_C) /= Name_uTag
14026 and then Chars (Old_C) /= Name_uParent
14028 Append_Elmt (Old_C, Comp_List);
14031 Next_Component (Old_C);
14035 Create_All_Components;
14038 -- If discriminants are not static, or if this is a multi-level type
14039 -- extension, we have to include all components of the parent type.
14041 Old_C := First_Component (Typ);
14042 while Present (Old_C) loop
14043 New_C := Create_Component (Old_C);
14047 Constrain_Component_Type
14048 (Old_C, Subt, Decl_Node, Typ, Constraints));
14049 Set_Is_Public (New_C, Is_Public (Subt));
14051 Next_Component (Old_C);
14056 end Create_Constrained_Components;
14058 ------------------------------------------
14059 -- Decimal_Fixed_Point_Type_Declaration --
14060 ------------------------------------------
14062 procedure Decimal_Fixed_Point_Type_Declaration
14066 Loc : constant Source_Ptr := Sloc (Def);
14067 Digs_Expr : constant Node_Id := Digits_Expression (Def);
14068 Delta_Expr : constant Node_Id := Delta_Expression (Def);
14069 Implicit_Base : Entity_Id;
14076 Check_SPARK_05_Restriction
14077 ("decimal fixed point type is not allowed", Def);
14078 Check_Restriction (No_Fixed_Point, Def);
14080 -- Create implicit base type
14083 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
14084 Set_Etype (Implicit_Base, Implicit_Base);
14086 -- Analyze and process delta expression
14088 Analyze_And_Resolve (Delta_Expr, Universal_Real);
14090 Check_Delta_Expression (Delta_Expr);
14091 Delta_Val := Expr_Value_R (Delta_Expr);
14093 -- Check delta is power of 10, and determine scale value from it
14099 Scale_Val := Uint_0;
14102 if Val < Ureal_1 then
14103 while Val < Ureal_1 loop
14104 Val := Val * Ureal_10;
14105 Scale_Val := Scale_Val + 1;
14108 if Scale_Val > 18 then
14109 Error_Msg_N ("scale exceeds maximum value of 18", Def);
14110 Scale_Val := UI_From_Int (+18);
14114 while Val > Ureal_1 loop
14115 Val := Val / Ureal_10;
14116 Scale_Val := Scale_Val - 1;
14119 if Scale_Val < -18 then
14120 Error_Msg_N ("scale is less than minimum value of -18", Def);
14121 Scale_Val := UI_From_Int (-18);
14125 if Val /= Ureal_1 then
14126 Error_Msg_N ("delta expression must be a power of 10", Def);
14127 Delta_Val := Ureal_10 ** (-Scale_Val);
14131 -- Set delta, scale and small (small = delta for decimal type)
14133 Set_Delta_Value (Implicit_Base, Delta_Val);
14134 Set_Scale_Value (Implicit_Base, Scale_Val);
14135 Set_Small_Value (Implicit_Base, Delta_Val);
14137 -- Analyze and process digits expression
14139 Analyze_And_Resolve (Digs_Expr, Any_Integer);
14140 Check_Digits_Expression (Digs_Expr);
14141 Digs_Val := Expr_Value (Digs_Expr);
14143 if Digs_Val > 18 then
14144 Digs_Val := UI_From_Int (+18);
14145 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
14148 Set_Digits_Value (Implicit_Base, Digs_Val);
14149 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
14151 -- Set range of base type from digits value for now. This will be
14152 -- expanded to represent the true underlying base range by Freeze.
14154 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
14156 -- Note: We leave size as zero for now, size will be set at freeze
14157 -- time. We have to do this for ordinary fixed-point, because the size
14158 -- depends on the specified small, and we might as well do the same for
14159 -- decimal fixed-point.
14161 pragma Assert (Esize (Implicit_Base) = Uint_0);
14163 -- If there are bounds given in the declaration use them as the
14164 -- bounds of the first named subtype.
14166 if Present (Real_Range_Specification (Def)) then
14168 RRS : constant Node_Id := Real_Range_Specification (Def);
14169 Low : constant Node_Id := Low_Bound (RRS);
14170 High : constant Node_Id := High_Bound (RRS);
14175 Analyze_And_Resolve (Low, Any_Real);
14176 Analyze_And_Resolve (High, Any_Real);
14177 Check_Real_Bound (Low);
14178 Check_Real_Bound (High);
14179 Low_Val := Expr_Value_R (Low);
14180 High_Val := Expr_Value_R (High);
14182 if Low_Val < (-Bound_Val) then
14184 ("range low bound too small for digits value", Low);
14185 Low_Val := -Bound_Val;
14188 if High_Val > Bound_Val then
14190 ("range high bound too large for digits value", High);
14191 High_Val := Bound_Val;
14194 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
14197 -- If no explicit range, use range that corresponds to given
14198 -- digits value. This will end up as the final range for the
14202 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
14205 -- Complete entity for first subtype. The inheritance of the rep item
14206 -- chain ensures that SPARK-related pragmas are not clobbered when the
14207 -- decimal fixed point type acts as a full view of a private type.
14209 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
14210 Set_Etype (T, Implicit_Base);
14211 Set_Size_Info (T, Implicit_Base);
14212 Inherit_Rep_Item_Chain (T, Implicit_Base);
14213 Set_Digits_Value (T, Digs_Val);
14214 Set_Delta_Value (T, Delta_Val);
14215 Set_Small_Value (T, Delta_Val);
14216 Set_Scale_Value (T, Scale_Val);
14217 Set_Is_Constrained (T);
14218 end Decimal_Fixed_Point_Type_Declaration;
14220 -----------------------------------
14221 -- Derive_Progenitor_Subprograms --
14222 -----------------------------------
14224 procedure Derive_Progenitor_Subprograms
14225 (Parent_Type : Entity_Id;
14226 Tagged_Type : Entity_Id)
14231 Iface_Elmt : Elmt_Id;
14232 Iface_Subp : Entity_Id;
14233 New_Subp : Entity_Id := Empty;
14234 Prim_Elmt : Elmt_Id;
14239 pragma Assert (Ada_Version >= Ada_2005
14240 and then Is_Record_Type (Tagged_Type)
14241 and then Is_Tagged_Type (Tagged_Type)
14242 and then Has_Interfaces (Tagged_Type));
14244 -- Step 1: Transfer to the full-view primitives associated with the
14245 -- partial-view that cover interface primitives. Conceptually this
14246 -- work should be done later by Process_Full_View; done here to
14247 -- simplify its implementation at later stages. It can be safely
14248 -- done here because interfaces must be visible in the partial and
14249 -- private view (RM 7.3(7.3/2)).
14251 -- Small optimization: This work is only required if the parent may
14252 -- have entities whose Alias attribute reference an interface primitive.
14253 -- Such a situation may occur if the parent is an abstract type and the
14254 -- primitive has not been yet overridden or if the parent is a generic
14255 -- formal type covering interfaces.
14257 -- If the tagged type is not abstract, it cannot have abstract
14258 -- primitives (the only entities in the list of primitives of
14259 -- non-abstract tagged types that can reference abstract primitives
14260 -- through its Alias attribute are the internal entities that have
14261 -- attribute Interface_Alias, and these entities are generated later
14262 -- by Add_Internal_Interface_Entities).
14264 if In_Private_Part (Current_Scope)
14265 and then (Is_Abstract_Type (Parent_Type)
14267 Is_Generic_Type (Parent_Type))
14269 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
14270 while Present (Elmt) loop
14271 Subp := Node (Elmt);
14273 -- At this stage it is not possible to have entities in the list
14274 -- of primitives that have attribute Interface_Alias.
14276 pragma Assert (No (Interface_Alias (Subp)));
14278 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
14280 if Is_Interface (Typ) then
14281 E := Find_Primitive_Covering_Interface
14282 (Tagged_Type => Tagged_Type,
14283 Iface_Prim => Subp);
14286 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
14288 Replace_Elmt (Elmt, E);
14289 Remove_Homonym (Subp);
14297 -- Step 2: Add primitives of progenitors that are not implemented by
14298 -- parents of Tagged_Type.
14300 if Present (Interfaces (Base_Type (Tagged_Type))) then
14301 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
14302 while Present (Iface_Elmt) loop
14303 Iface := Node (Iface_Elmt);
14305 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
14306 while Present (Prim_Elmt) loop
14307 Iface_Subp := Node (Prim_Elmt);
14309 -- Exclude derivation of predefined primitives except those
14310 -- that come from source, or are inherited from one that comes
14311 -- from source. Required to catch declarations of equality
14312 -- operators of interfaces. For example:
14314 -- type Iface is interface;
14315 -- function "=" (Left, Right : Iface) return Boolean;
14317 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
14318 or else Comes_From_Source (Ultimate_Alias (Iface_Subp))
14320 E := Find_Primitive_Covering_Interface
14321 (Tagged_Type => Tagged_Type,
14322 Iface_Prim => Iface_Subp);
14324 -- If not found we derive a new primitive leaving its alias
14325 -- attribute referencing the interface primitive.
14329 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14331 -- Ada 2012 (AI05-0197): If the covering primitive's name
14332 -- differs from the name of the interface primitive then it
14333 -- is a private primitive inherited from a parent type. In
14334 -- such case, given that Tagged_Type covers the interface,
14335 -- the inherited private primitive becomes visible. For such
14336 -- purpose we add a new entity that renames the inherited
14337 -- private primitive.
14339 elsif Chars (E) /= Chars (Iface_Subp) then
14340 pragma Assert (Has_Suffix (E, 'P'));
14342 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14343 Set_Alias (New_Subp, E);
14344 Set_Is_Abstract_Subprogram (New_Subp,
14345 Is_Abstract_Subprogram (E));
14347 -- Propagate to the full view interface entities associated
14348 -- with the partial view.
14350 elsif In_Private_Part (Current_Scope)
14351 and then Present (Alias (E))
14352 and then Alias (E) = Iface_Subp
14354 List_Containing (Parent (E)) /=
14355 Private_Declarations
14357 (Unit_Declaration_Node (Current_Scope)))
14359 Append_Elmt (E, Primitive_Operations (Tagged_Type));
14363 Next_Elmt (Prim_Elmt);
14366 Next_Elmt (Iface_Elmt);
14369 end Derive_Progenitor_Subprograms;
14371 -----------------------
14372 -- Derive_Subprogram --
14373 -----------------------
14375 procedure Derive_Subprogram
14376 (New_Subp : in out Entity_Id;
14377 Parent_Subp : Entity_Id;
14378 Derived_Type : Entity_Id;
14379 Parent_Type : Entity_Id;
14380 Actual_Subp : Entity_Id := Empty)
14382 Formal : Entity_Id;
14383 -- Formal parameter of parent primitive operation
14385 Formal_Of_Actual : Entity_Id;
14386 -- Formal parameter of actual operation, when the derivation is to
14387 -- create a renaming for a primitive operation of an actual in an
14390 New_Formal : Entity_Id;
14391 -- Formal of inherited operation
14393 Visible_Subp : Entity_Id := Parent_Subp;
14395 function Is_Private_Overriding return Boolean;
14396 -- If Subp is a private overriding of a visible operation, the inherited
14397 -- operation derives from the overridden op (even though its body is the
14398 -- overriding one) and the inherited operation is visible now. See
14399 -- sem_disp to see the full details of the handling of the overridden
14400 -- subprogram, which is removed from the list of primitive operations of
14401 -- the type. The overridden subprogram is saved locally in Visible_Subp,
14402 -- and used to diagnose abstract operations that need overriding in the
14405 procedure Replace_Type (Id, New_Id : Entity_Id);
14406 -- When the type is an anonymous access type, create a new access type
14407 -- designating the derived type.
14409 procedure Set_Derived_Name;
14410 -- This procedure sets the appropriate Chars name for New_Subp. This
14411 -- is normally just a copy of the parent name. An exception arises for
14412 -- type support subprograms, where the name is changed to reflect the
14413 -- name of the derived type, e.g. if type foo is derived from type bar,
14414 -- then a procedure barDA is derived with a name fooDA.
14416 ---------------------------
14417 -- Is_Private_Overriding --
14418 ---------------------------
14420 function Is_Private_Overriding return Boolean is
14424 -- If the parent is not a dispatching operation there is no
14425 -- need to investigate overridings
14427 if not Is_Dispatching_Operation (Parent_Subp) then
14431 -- The visible operation that is overridden is a homonym of the
14432 -- parent subprogram. We scan the homonym chain to find the one
14433 -- whose alias is the subprogram we are deriving.
14435 Prev := Current_Entity (Parent_Subp);
14436 while Present (Prev) loop
14437 if Ekind (Prev) = Ekind (Parent_Subp)
14438 and then Alias (Prev) = Parent_Subp
14439 and then Scope (Parent_Subp) = Scope (Prev)
14440 and then not Is_Hidden (Prev)
14442 Visible_Subp := Prev;
14446 Prev := Homonym (Prev);
14450 end Is_Private_Overriding;
14456 procedure Replace_Type (Id, New_Id : Entity_Id) is
14457 Id_Type : constant Entity_Id := Etype (Id);
14458 Acc_Type : Entity_Id;
14459 Par : constant Node_Id := Parent (Derived_Type);
14462 -- When the type is an anonymous access type, create a new access
14463 -- type designating the derived type. This itype must be elaborated
14464 -- at the point of the derivation, not on subsequent calls that may
14465 -- be out of the proper scope for Gigi, so we insert a reference to
14466 -- it after the derivation.
14468 if Ekind (Id_Type) = E_Anonymous_Access_Type then
14470 Desig_Typ : Entity_Id := Designated_Type (Id_Type);
14473 if Ekind (Desig_Typ) = E_Record_Type_With_Private
14474 and then Present (Full_View (Desig_Typ))
14475 and then not Is_Private_Type (Parent_Type)
14477 Desig_Typ := Full_View (Desig_Typ);
14480 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
14482 -- Ada 2005 (AI-251): Handle also derivations of abstract
14483 -- interface primitives.
14485 or else (Is_Interface (Desig_Typ)
14486 and then not Is_Class_Wide_Type (Desig_Typ))
14488 Acc_Type := New_Copy (Id_Type);
14489 Set_Etype (Acc_Type, Acc_Type);
14490 Set_Scope (Acc_Type, New_Subp);
14492 -- Set size of anonymous access type. If we have an access
14493 -- to an unconstrained array, this is a fat pointer, so it
14494 -- is sizes at twice addtress size.
14496 if Is_Array_Type (Desig_Typ)
14497 and then not Is_Constrained (Desig_Typ)
14499 Init_Size (Acc_Type, 2 * System_Address_Size);
14501 -- Other cases use a thin pointer
14504 Init_Size (Acc_Type, System_Address_Size);
14507 -- Set remaining characterstics of anonymous access type
14509 Init_Alignment (Acc_Type);
14510 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
14512 Set_Etype (New_Id, Acc_Type);
14513 Set_Scope (New_Id, New_Subp);
14515 -- Create a reference to it
14517 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
14520 Set_Etype (New_Id, Id_Type);
14524 -- In Ada2012, a formal may have an incomplete type but the type
14525 -- derivation that inherits the primitive follows the full view.
14527 elsif Base_Type (Id_Type) = Base_Type (Parent_Type)
14529 (Ekind (Id_Type) = E_Record_Type_With_Private
14530 and then Present (Full_View (Id_Type))
14532 Base_Type (Full_View (Id_Type)) = Base_Type (Parent_Type))
14534 (Ada_Version >= Ada_2012
14535 and then Ekind (Id_Type) = E_Incomplete_Type
14536 and then Full_View (Id_Type) = Parent_Type)
14538 -- Constraint checks on formals are generated during expansion,
14539 -- based on the signature of the original subprogram. The bounds
14540 -- of the derived type are not relevant, and thus we can use
14541 -- the base type for the formals. However, the return type may be
14542 -- used in a context that requires that the proper static bounds
14543 -- be used (a case statement, for example) and for those cases
14544 -- we must use the derived type (first subtype), not its base.
14546 -- If the derived_type_definition has no constraints, we know that
14547 -- the derived type has the same constraints as the first subtype
14548 -- of the parent, and we can also use it rather than its base,
14549 -- which can lead to more efficient code.
14551 if Etype (Id) = Parent_Type then
14552 if Is_Scalar_Type (Parent_Type)
14554 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
14556 Set_Etype (New_Id, Derived_Type);
14558 elsif Nkind (Par) = N_Full_Type_Declaration
14560 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
14563 (Subtype_Indication (Type_Definition (Par)))
14565 Set_Etype (New_Id, Derived_Type);
14568 Set_Etype (New_Id, Base_Type (Derived_Type));
14572 Set_Etype (New_Id, Base_Type (Derived_Type));
14576 Set_Etype (New_Id, Etype (Id));
14580 ----------------------
14581 -- Set_Derived_Name --
14582 ----------------------
14584 procedure Set_Derived_Name is
14585 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
14587 if Nm = TSS_Null then
14588 Set_Chars (New_Subp, Chars (Parent_Subp));
14590 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
14592 end Set_Derived_Name;
14594 -- Start of processing for Derive_Subprogram
14597 New_Subp := New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
14598 Set_Ekind (New_Subp, Ekind (Parent_Subp));
14600 -- Check whether the inherited subprogram is a private operation that
14601 -- should be inherited but not yet made visible. Such subprograms can
14602 -- become visible at a later point (e.g., the private part of a public
14603 -- child unit) via Declare_Inherited_Private_Subprograms. If the
14604 -- following predicate is true, then this is not such a private
14605 -- operation and the subprogram simply inherits the name of the parent
14606 -- subprogram. Note the special check for the names of controlled
14607 -- operations, which are currently exempted from being inherited with
14608 -- a hidden name because they must be findable for generation of
14609 -- implicit run-time calls.
14611 if not Is_Hidden (Parent_Subp)
14612 or else Is_Internal (Parent_Subp)
14613 or else Is_Private_Overriding
14614 or else Is_Internal_Name (Chars (Parent_Subp))
14615 or else Nam_In (Chars (Parent_Subp), Name_Initialize,
14621 -- An inherited dispatching equality will be overridden by an internally
14622 -- generated one, or by an explicit one, so preserve its name and thus
14623 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
14624 -- private operation it may become invisible if the full view has
14625 -- progenitors, and the dispatch table will be malformed.
14626 -- We check that the type is limited to handle the anomalous declaration
14627 -- of Limited_Controlled, which is derived from a non-limited type, and
14628 -- which is handled specially elsewhere as well.
14630 elsif Chars (Parent_Subp) = Name_Op_Eq
14631 and then Is_Dispatching_Operation (Parent_Subp)
14632 and then Etype (Parent_Subp) = Standard_Boolean
14633 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
14635 Etype (First_Formal (Parent_Subp)) =
14636 Etype (Next_Formal (First_Formal (Parent_Subp)))
14640 -- If parent is hidden, this can be a regular derivation if the
14641 -- parent is immediately visible in a non-instantiating context,
14642 -- or if we are in the private part of an instance. This test
14643 -- should still be refined ???
14645 -- The test for In_Instance_Not_Visible avoids inheriting the derived
14646 -- operation as a non-visible operation in cases where the parent
14647 -- subprogram might not be visible now, but was visible within the
14648 -- original generic, so it would be wrong to make the inherited
14649 -- subprogram non-visible now. (Not clear if this test is fully
14650 -- correct; are there any cases where we should declare the inherited
14651 -- operation as not visible to avoid it being overridden, e.g., when
14652 -- the parent type is a generic actual with private primitives ???)
14654 -- (they should be treated the same as other private inherited
14655 -- subprograms, but it's not clear how to do this cleanly). ???
14657 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
14658 and then Is_Immediately_Visible (Parent_Subp)
14659 and then not In_Instance)
14660 or else In_Instance_Not_Visible
14664 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
14665 -- overrides an interface primitive because interface primitives
14666 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
14668 elsif Ada_Version >= Ada_2005
14669 and then Is_Dispatching_Operation (Parent_Subp)
14670 and then Covers_Some_Interface (Parent_Subp)
14674 -- Otherwise, the type is inheriting a private operation, so enter
14675 -- it with a special name so it can't be overridden.
14678 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
14681 Set_Parent (New_Subp, Parent (Derived_Type));
14683 if Present (Actual_Subp) then
14684 Replace_Type (Actual_Subp, New_Subp);
14686 Replace_Type (Parent_Subp, New_Subp);
14689 Conditional_Delay (New_Subp, Parent_Subp);
14691 -- If we are creating a renaming for a primitive operation of an
14692 -- actual of a generic derived type, we must examine the signature
14693 -- of the actual primitive, not that of the generic formal, which for
14694 -- example may be an interface. However the name and initial value
14695 -- of the inherited operation are those of the formal primitive.
14697 Formal := First_Formal (Parent_Subp);
14699 if Present (Actual_Subp) then
14700 Formal_Of_Actual := First_Formal (Actual_Subp);
14702 Formal_Of_Actual := Empty;
14705 while Present (Formal) loop
14706 New_Formal := New_Copy (Formal);
14708 -- Normally we do not go copying parents, but in the case of
14709 -- formals, we need to link up to the declaration (which is the
14710 -- parameter specification), and it is fine to link up to the
14711 -- original formal's parameter specification in this case.
14713 Set_Parent (New_Formal, Parent (Formal));
14714 Append_Entity (New_Formal, New_Subp);
14716 if Present (Formal_Of_Actual) then
14717 Replace_Type (Formal_Of_Actual, New_Formal);
14718 Next_Formal (Formal_Of_Actual);
14720 Replace_Type (Formal, New_Formal);
14723 Next_Formal (Formal);
14726 -- If this derivation corresponds to a tagged generic actual, then
14727 -- primitive operations rename those of the actual. Otherwise the
14728 -- primitive operations rename those of the parent type, If the parent
14729 -- renames an intrinsic operator, so does the new subprogram. We except
14730 -- concatenation, which is always properly typed, and does not get
14731 -- expanded as other intrinsic operations.
14733 if No (Actual_Subp) then
14734 if Is_Intrinsic_Subprogram (Parent_Subp) then
14735 Set_Is_Intrinsic_Subprogram (New_Subp);
14737 if Present (Alias (Parent_Subp))
14738 and then Chars (Parent_Subp) /= Name_Op_Concat
14740 Set_Alias (New_Subp, Alias (Parent_Subp));
14742 Set_Alias (New_Subp, Parent_Subp);
14746 Set_Alias (New_Subp, Parent_Subp);
14750 Set_Alias (New_Subp, Actual_Subp);
14753 -- Inherit the "ghostness" from the parent subprogram
14755 if Is_Ghost_Entity (Alias (New_Subp)) then
14756 Set_Is_Ghost_Entity (New_Subp);
14759 -- Derived subprograms of a tagged type must inherit the convention
14760 -- of the parent subprogram (a requirement of AI-117). Derived
14761 -- subprograms of untagged types simply get convention Ada by default.
14763 -- If the derived type is a tagged generic formal type with unknown
14764 -- discriminants, its convention is intrinsic (RM 6.3.1 (8)).
14766 -- However, if the type is derived from a generic formal, the further
14767 -- inherited subprogram has the convention of the non-generic ancestor.
14768 -- Otherwise there would be no way to override the operation.
14769 -- (This is subject to forthcoming ARG discussions).
14771 if Is_Tagged_Type (Derived_Type) then
14772 if Is_Generic_Type (Derived_Type)
14773 and then Has_Unknown_Discriminants (Derived_Type)
14775 Set_Convention (New_Subp, Convention_Intrinsic);
14778 if Is_Generic_Type (Parent_Type)
14779 and then Has_Unknown_Discriminants (Parent_Type)
14781 Set_Convention (New_Subp, Convention (Alias (Parent_Subp)));
14783 Set_Convention (New_Subp, Convention (Parent_Subp));
14788 -- Predefined controlled operations retain their name even if the parent
14789 -- is hidden (see above), but they are not primitive operations if the
14790 -- ancestor is not visible, for example if the parent is a private
14791 -- extension completed with a controlled extension. Note that a full
14792 -- type that is controlled can break privacy: the flag Is_Controlled is
14793 -- set on both views of the type.
14795 if Is_Controlled (Parent_Type)
14796 and then Nam_In (Chars (Parent_Subp), Name_Initialize,
14799 and then Is_Hidden (Parent_Subp)
14800 and then not Is_Visibly_Controlled (Parent_Type)
14802 Set_Is_Hidden (New_Subp);
14805 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
14806 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
14808 if Ekind (Parent_Subp) = E_Procedure then
14809 Set_Is_Valued_Procedure
14810 (New_Subp, Is_Valued_Procedure (Parent_Subp));
14812 Set_Has_Controlling_Result
14813 (New_Subp, Has_Controlling_Result (Parent_Subp));
14816 -- No_Return must be inherited properly. If this is overridden in the
14817 -- case of a dispatching operation, then a check is made in Sem_Disp
14818 -- that the overriding operation is also No_Return (no such check is
14819 -- required for the case of non-dispatching operation.
14821 Set_No_Return (New_Subp, No_Return (Parent_Subp));
14823 -- A derived function with a controlling result is abstract. If the
14824 -- Derived_Type is a nonabstract formal generic derived type, then
14825 -- inherited operations are not abstract: the required check is done at
14826 -- instantiation time. If the derivation is for a generic actual, the
14827 -- function is not abstract unless the actual is.
14829 if Is_Generic_Type (Derived_Type)
14830 and then not Is_Abstract_Type (Derived_Type)
14834 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
14835 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
14837 -- A subprogram subject to pragma Extensions_Visible with value False
14838 -- requires overriding if the subprogram has at least one controlling
14839 -- OUT parameter (SPARK RM 6.1.7(6)).
14841 elsif Ada_Version >= Ada_2005
14842 and then (Is_Abstract_Subprogram (Alias (New_Subp))
14843 or else (Is_Tagged_Type (Derived_Type)
14844 and then Etype (New_Subp) = Derived_Type
14845 and then not Is_Null_Extension (Derived_Type))
14846 or else (Is_Tagged_Type (Derived_Type)
14847 and then Ekind (Etype (New_Subp)) =
14848 E_Anonymous_Access_Type
14849 and then Designated_Type (Etype (New_Subp)) =
14851 and then not Is_Null_Extension (Derived_Type))
14852 or else (Comes_From_Source (Alias (New_Subp))
14853 and then Is_EVF_Procedure (Alias (New_Subp))))
14854 and then No (Actual_Subp)
14856 if not Is_Tagged_Type (Derived_Type)
14857 or else Is_Abstract_Type (Derived_Type)
14858 or else Is_Abstract_Subprogram (Alias (New_Subp))
14860 Set_Is_Abstract_Subprogram (New_Subp);
14862 Set_Requires_Overriding (New_Subp);
14865 elsif Ada_Version < Ada_2005
14866 and then (Is_Abstract_Subprogram (Alias (New_Subp))
14867 or else (Is_Tagged_Type (Derived_Type)
14868 and then Etype (New_Subp) = Derived_Type
14869 and then No (Actual_Subp)))
14871 Set_Is_Abstract_Subprogram (New_Subp);
14873 -- AI05-0097 : an inherited operation that dispatches on result is
14874 -- abstract if the derived type is abstract, even if the parent type
14875 -- is concrete and the derived type is a null extension.
14877 elsif Has_Controlling_Result (Alias (New_Subp))
14878 and then Is_Abstract_Type (Etype (New_Subp))
14880 Set_Is_Abstract_Subprogram (New_Subp);
14882 -- Finally, if the parent type is abstract we must verify that all
14883 -- inherited operations are either non-abstract or overridden, or that
14884 -- the derived type itself is abstract (this check is performed at the
14885 -- end of a package declaration, in Check_Abstract_Overriding). A
14886 -- private overriding in the parent type will not be visible in the
14887 -- derivation if we are not in an inner package or in a child unit of
14888 -- the parent type, in which case the abstractness of the inherited
14889 -- operation is carried to the new subprogram.
14891 elsif Is_Abstract_Type (Parent_Type)
14892 and then not In_Open_Scopes (Scope (Parent_Type))
14893 and then Is_Private_Overriding
14894 and then Is_Abstract_Subprogram (Visible_Subp)
14896 if No (Actual_Subp) then
14897 Set_Alias (New_Subp, Visible_Subp);
14898 Set_Is_Abstract_Subprogram (New_Subp, True);
14901 -- If this is a derivation for an instance of a formal derived
14902 -- type, abstractness comes from the primitive operation of the
14903 -- actual, not from the operation inherited from the ancestor.
14905 Set_Is_Abstract_Subprogram
14906 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
14910 New_Overloaded_Entity (New_Subp, Derived_Type);
14912 -- Check for case of a derived subprogram for the instantiation of a
14913 -- formal derived tagged type, if so mark the subprogram as dispatching
14914 -- and inherit the dispatching attributes of the actual subprogram. The
14915 -- derived subprogram is effectively renaming of the actual subprogram,
14916 -- so it needs to have the same attributes as the actual.
14918 if Present (Actual_Subp)
14919 and then Is_Dispatching_Operation (Actual_Subp)
14921 Set_Is_Dispatching_Operation (New_Subp);
14923 if Present (DTC_Entity (Actual_Subp)) then
14924 Set_DTC_Entity (New_Subp, DTC_Entity (Actual_Subp));
14925 Set_DT_Position_Value (New_Subp, DT_Position (Actual_Subp));
14929 -- Indicate that a derived subprogram does not require a body and that
14930 -- it does not require processing of default expressions.
14932 Set_Has_Completion (New_Subp);
14933 Set_Default_Expressions_Processed (New_Subp);
14935 if Ekind (New_Subp) = E_Function then
14936 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
14938 end Derive_Subprogram;
14940 ------------------------
14941 -- Derive_Subprograms --
14942 ------------------------
14944 procedure Derive_Subprograms
14945 (Parent_Type : Entity_Id;
14946 Derived_Type : Entity_Id;
14947 Generic_Actual : Entity_Id := Empty)
14949 Op_List : constant Elist_Id :=
14950 Collect_Primitive_Operations (Parent_Type);
14952 function Check_Derived_Type return Boolean;
14953 -- Check that all the entities derived from Parent_Type are found in
14954 -- the list of primitives of Derived_Type exactly in the same order.
14956 procedure Derive_Interface_Subprogram
14957 (New_Subp : in out Entity_Id;
14959 Actual_Subp : Entity_Id);
14960 -- Derive New_Subp from the ultimate alias of the parent subprogram Subp
14961 -- (which is an interface primitive). If Generic_Actual is present then
14962 -- Actual_Subp is the actual subprogram corresponding with the generic
14963 -- subprogram Subp.
14965 function Check_Derived_Type return Boolean is
14969 New_Subp : Entity_Id;
14974 -- Traverse list of entities in the current scope searching for
14975 -- an incomplete type whose full-view is derived type
14977 E := First_Entity (Scope (Derived_Type));
14978 while Present (E) and then E /= Derived_Type loop
14979 if Ekind (E) = E_Incomplete_Type
14980 and then Present (Full_View (E))
14981 and then Full_View (E) = Derived_Type
14983 -- Disable this test if Derived_Type completes an incomplete
14984 -- type because in such case more primitives can be added
14985 -- later to the list of primitives of Derived_Type by routine
14986 -- Process_Incomplete_Dependents
14991 E := Next_Entity (E);
14994 List := Collect_Primitive_Operations (Derived_Type);
14995 Elmt := First_Elmt (List);
14997 Op_Elmt := First_Elmt (Op_List);
14998 while Present (Op_Elmt) loop
14999 Subp := Node (Op_Elmt);
15000 New_Subp := Node (Elmt);
15002 -- At this early stage Derived_Type has no entities with attribute
15003 -- Interface_Alias. In addition, such primitives are always
15004 -- located at the end of the list of primitives of Parent_Type.
15005 -- Therefore, if found we can safely stop processing pending
15008 exit when Present (Interface_Alias (Subp));
15010 -- Handle hidden entities
15012 if not Is_Predefined_Dispatching_Operation (Subp)
15013 and then Is_Hidden (Subp)
15015 if Present (New_Subp)
15016 and then Primitive_Names_Match (Subp, New_Subp)
15022 if not Present (New_Subp)
15023 or else Ekind (Subp) /= Ekind (New_Subp)
15024 or else not Primitive_Names_Match (Subp, New_Subp)
15032 Next_Elmt (Op_Elmt);
15036 end Check_Derived_Type;
15038 ---------------------------------
15039 -- Derive_Interface_Subprogram --
15040 ---------------------------------
15042 procedure Derive_Interface_Subprogram
15043 (New_Subp : in out Entity_Id;
15045 Actual_Subp : Entity_Id)
15047 Iface_Subp : constant Entity_Id := Ultimate_Alias (Subp);
15048 Iface_Type : constant Entity_Id := Find_Dispatching_Type (Iface_Subp);
15051 pragma Assert (Is_Interface (Iface_Type));
15054 (New_Subp => New_Subp,
15055 Parent_Subp => Iface_Subp,
15056 Derived_Type => Derived_Type,
15057 Parent_Type => Iface_Type,
15058 Actual_Subp => Actual_Subp);
15060 -- Given that this new interface entity corresponds with a primitive
15061 -- of the parent that was not overridden we must leave it associated
15062 -- with its parent primitive to ensure that it will share the same
15063 -- dispatch table slot when overridden. We must set the Alias to Subp
15064 -- (instead of Iface_Subp), and we must fix Is_Abstract_Subprogram
15065 -- (in case we inherited Subp from Iface_Type via a nonabstract
15066 -- generic formal type).
15068 if No (Actual_Subp) then
15069 Set_Alias (New_Subp, Subp);
15072 T : Entity_Id := Find_Dispatching_Type (Subp);
15074 while Etype (T) /= T loop
15075 if Is_Generic_Type (T) and then not Is_Abstract_Type (T) then
15076 Set_Is_Abstract_Subprogram (New_Subp, False);
15084 -- For instantiations this is not needed since the previous call to
15085 -- Derive_Subprogram leaves the entity well decorated.
15088 pragma Assert (Alias (New_Subp) = Actual_Subp);
15091 end Derive_Interface_Subprogram;
15095 Alias_Subp : Entity_Id;
15096 Act_List : Elist_Id;
15097 Act_Elmt : Elmt_Id;
15098 Act_Subp : Entity_Id := Empty;
15100 Need_Search : Boolean := False;
15101 New_Subp : Entity_Id := Empty;
15102 Parent_Base : Entity_Id;
15105 -- Start of processing for Derive_Subprograms
15108 if Ekind (Parent_Type) = E_Record_Type_With_Private
15109 and then Has_Discriminants (Parent_Type)
15110 and then Present (Full_View (Parent_Type))
15112 Parent_Base := Full_View (Parent_Type);
15114 Parent_Base := Parent_Type;
15117 if Present (Generic_Actual) then
15118 Act_List := Collect_Primitive_Operations (Generic_Actual);
15119 Act_Elmt := First_Elmt (Act_List);
15121 Act_List := No_Elist;
15122 Act_Elmt := No_Elmt;
15125 -- Derive primitives inherited from the parent. Note that if the generic
15126 -- actual is present, this is not really a type derivation, it is a
15127 -- completion within an instance.
15129 -- Case 1: Derived_Type does not implement interfaces
15131 if not Is_Tagged_Type (Derived_Type)
15132 or else (not Has_Interfaces (Derived_Type)
15133 and then not (Present (Generic_Actual)
15134 and then Has_Interfaces (Generic_Actual)))
15136 Elmt := First_Elmt (Op_List);
15137 while Present (Elmt) loop
15138 Subp := Node (Elmt);
15140 -- Literals are derived earlier in the process of building the
15141 -- derived type, and are skipped here.
15143 if Ekind (Subp) = E_Enumeration_Literal then
15146 -- The actual is a direct descendant and the common primitive
15147 -- operations appear in the same order.
15149 -- If the generic parent type is present, the derived type is an
15150 -- instance of a formal derived type, and within the instance its
15151 -- operations are those of the actual. We derive from the formal
15152 -- type but make the inherited operations aliases of the
15153 -- corresponding operations of the actual.
15156 pragma Assert (No (Node (Act_Elmt))
15157 or else (Primitive_Names_Match (Subp, Node (Act_Elmt))
15160 (Subp, Node (Act_Elmt),
15161 Skip_Controlling_Formals => True)));
15164 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
15166 if Present (Act_Elmt) then
15167 Next_Elmt (Act_Elmt);
15174 -- Case 2: Derived_Type implements interfaces
15177 -- If the parent type has no predefined primitives we remove
15178 -- predefined primitives from the list of primitives of generic
15179 -- actual to simplify the complexity of this algorithm.
15181 if Present (Generic_Actual) then
15183 Has_Predefined_Primitives : Boolean := False;
15186 -- Check if the parent type has predefined primitives
15188 Elmt := First_Elmt (Op_List);
15189 while Present (Elmt) loop
15190 Subp := Node (Elmt);
15192 if Is_Predefined_Dispatching_Operation (Subp)
15193 and then not Comes_From_Source (Ultimate_Alias (Subp))
15195 Has_Predefined_Primitives := True;
15202 -- Remove predefined primitives of Generic_Actual. We must use
15203 -- an auxiliary list because in case of tagged types the value
15204 -- returned by Collect_Primitive_Operations is the value stored
15205 -- in its Primitive_Operations attribute (and we don't want to
15206 -- modify its current contents).
15208 if not Has_Predefined_Primitives then
15210 Aux_List : constant Elist_Id := New_Elmt_List;
15213 Elmt := First_Elmt (Act_List);
15214 while Present (Elmt) loop
15215 Subp := Node (Elmt);
15217 if not Is_Predefined_Dispatching_Operation (Subp)
15218 or else Comes_From_Source (Subp)
15220 Append_Elmt (Subp, Aux_List);
15226 Act_List := Aux_List;
15230 Act_Elmt := First_Elmt (Act_List);
15231 Act_Subp := Node (Act_Elmt);
15235 -- Stage 1: If the generic actual is not present we derive the
15236 -- primitives inherited from the parent type. If the generic parent
15237 -- type is present, the derived type is an instance of a formal
15238 -- derived type, and within the instance its operations are those of
15239 -- the actual. We derive from the formal type but make the inherited
15240 -- operations aliases of the corresponding operations of the actual.
15242 Elmt := First_Elmt (Op_List);
15243 while Present (Elmt) loop
15244 Subp := Node (Elmt);
15245 Alias_Subp := Ultimate_Alias (Subp);
15247 -- Do not derive internal entities of the parent that link
15248 -- interface primitives with their covering primitive. These
15249 -- entities will be added to this type when frozen.
15251 if Present (Interface_Alias (Subp)) then
15255 -- If the generic actual is present find the corresponding
15256 -- operation in the generic actual. If the parent type is a
15257 -- direct ancestor of the derived type then, even if it is an
15258 -- interface, the operations are inherited from the primary
15259 -- dispatch table and are in the proper order. If we detect here
15260 -- that primitives are not in the same order we traverse the list
15261 -- of primitive operations of the actual to find the one that
15262 -- implements the interface primitive.
15266 (Present (Generic_Actual)
15267 and then Present (Act_Subp)
15269 (Primitive_Names_Match (Subp, Act_Subp)
15271 Type_Conformant (Subp, Act_Subp,
15272 Skip_Controlling_Formals => True)))
15274 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual,
15275 Use_Full_View => True));
15277 -- Remember that we need searching for all pending primitives
15279 Need_Search := True;
15281 -- Handle entities associated with interface primitives
15283 if Present (Alias_Subp)
15284 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
15285 and then not Is_Predefined_Dispatching_Operation (Subp)
15287 -- Search for the primitive in the homonym chain
15290 Find_Primitive_Covering_Interface
15291 (Tagged_Type => Generic_Actual,
15292 Iface_Prim => Alias_Subp);
15294 -- Previous search may not locate primitives covering
15295 -- interfaces defined in generics units or instantiations.
15296 -- (it fails if the covering primitive has formals whose
15297 -- type is also defined in generics or instantiations).
15298 -- In such case we search in the list of primitives of the
15299 -- generic actual for the internal entity that links the
15300 -- interface primitive and the covering primitive.
15303 and then Is_Generic_Type (Parent_Type)
15305 -- This code has been designed to handle only generic
15306 -- formals that implement interfaces that are defined
15307 -- in a generic unit or instantiation. If this code is
15308 -- needed for other cases we must review it because
15309 -- (given that it relies on Original_Location to locate
15310 -- the primitive of Generic_Actual that covers the
15311 -- interface) it could leave linked through attribute
15312 -- Alias entities of unrelated instantiations).
15316 (Scope (Find_Dispatching_Type (Alias_Subp)))
15318 Instantiation_Depth
15319 (Sloc (Find_Dispatching_Type (Alias_Subp))) > 0);
15322 Iface_Prim_Loc : constant Source_Ptr :=
15323 Original_Location (Sloc (Alias_Subp));
15330 First_Elmt (Primitive_Operations (Generic_Actual));
15332 Search : while Present (Elmt) loop
15333 Prim := Node (Elmt);
15335 if Present (Interface_Alias (Prim))
15336 and then Original_Location
15337 (Sloc (Interface_Alias (Prim))) =
15340 Act_Subp := Alias (Prim);
15349 pragma Assert (Present (Act_Subp)
15350 or else Is_Abstract_Type (Generic_Actual)
15351 or else Serious_Errors_Detected > 0);
15353 -- Handle predefined primitives plus the rest of user-defined
15357 Act_Elmt := First_Elmt (Act_List);
15358 while Present (Act_Elmt) loop
15359 Act_Subp := Node (Act_Elmt);
15361 exit when Primitive_Names_Match (Subp, Act_Subp)
15362 and then Type_Conformant
15364 Skip_Controlling_Formals => True)
15365 and then No (Interface_Alias (Act_Subp));
15367 Next_Elmt (Act_Elmt);
15370 if No (Act_Elmt) then
15376 -- Case 1: If the parent is a limited interface then it has the
15377 -- predefined primitives of synchronized interfaces. However, the
15378 -- actual type may be a non-limited type and hence it does not
15379 -- have such primitives.
15381 if Present (Generic_Actual)
15382 and then not Present (Act_Subp)
15383 and then Is_Limited_Interface (Parent_Base)
15384 and then Is_Predefined_Interface_Primitive (Subp)
15388 -- Case 2: Inherit entities associated with interfaces that were
15389 -- not covered by the parent type. We exclude here null interface
15390 -- primitives because they do not need special management.
15392 -- We also exclude interface operations that are renamings. If the
15393 -- subprogram is an explicit renaming of an interface primitive,
15394 -- it is a regular primitive operation, and the presence of its
15395 -- alias is not relevant: it has to be derived like any other
15398 elsif Present (Alias (Subp))
15399 and then Nkind (Unit_Declaration_Node (Subp)) /=
15400 N_Subprogram_Renaming_Declaration
15401 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
15403 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
15404 and then Null_Present (Parent (Alias_Subp)))
15406 -- If this is an abstract private type then we transfer the
15407 -- derivation of the interface primitive from the partial view
15408 -- to the full view. This is safe because all the interfaces
15409 -- must be visible in the partial view. Done to avoid adding
15410 -- a new interface derivation to the private part of the
15411 -- enclosing package; otherwise this new derivation would be
15412 -- decorated as hidden when the analysis of the enclosing
15413 -- package completes.
15415 if Is_Abstract_Type (Derived_Type)
15416 and then In_Private_Part (Current_Scope)
15417 and then Has_Private_Declaration (Derived_Type)
15420 Partial_View : Entity_Id;
15425 Partial_View := First_Entity (Current_Scope);
15427 exit when No (Partial_View)
15428 or else (Has_Private_Declaration (Partial_View)
15430 Full_View (Partial_View) = Derived_Type);
15432 Next_Entity (Partial_View);
15435 -- If the partial view was not found then the source code
15436 -- has errors and the derivation is not needed.
15438 if Present (Partial_View) then
15440 First_Elmt (Primitive_Operations (Partial_View));
15441 while Present (Elmt) loop
15442 Ent := Node (Elmt);
15444 if Present (Alias (Ent))
15445 and then Ultimate_Alias (Ent) = Alias (Subp)
15448 (Ent, Primitive_Operations (Derived_Type));
15455 -- If the interface primitive was not found in the
15456 -- partial view then this interface primitive was
15457 -- overridden. We add a derivation to activate in
15458 -- Derive_Progenitor_Subprograms the machinery to
15462 Derive_Interface_Subprogram
15463 (New_Subp => New_Subp,
15465 Actual_Subp => Act_Subp);
15470 Derive_Interface_Subprogram
15471 (New_Subp => New_Subp,
15473 Actual_Subp => Act_Subp);
15476 -- Case 3: Common derivation
15480 (New_Subp => New_Subp,
15481 Parent_Subp => Subp,
15482 Derived_Type => Derived_Type,
15483 Parent_Type => Parent_Base,
15484 Actual_Subp => Act_Subp);
15487 -- No need to update Act_Elm if we must search for the
15488 -- corresponding operation in the generic actual
15491 and then Present (Act_Elmt)
15493 Next_Elmt (Act_Elmt);
15494 Act_Subp := Node (Act_Elmt);
15501 -- Inherit additional operations from progenitors. If the derived
15502 -- type is a generic actual, there are not new primitive operations
15503 -- for the type because it has those of the actual, and therefore
15504 -- nothing needs to be done. The renamings generated above are not
15505 -- primitive operations, and their purpose is simply to make the
15506 -- proper operations visible within an instantiation.
15508 if No (Generic_Actual) then
15509 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
15513 -- Final check: Direct descendants must have their primitives in the
15514 -- same order. We exclude from this test untagged types and instances
15515 -- of formal derived types. We skip this test if we have already
15516 -- reported serious errors in the sources.
15518 pragma Assert (not Is_Tagged_Type (Derived_Type)
15519 or else Present (Generic_Actual)
15520 or else Serious_Errors_Detected > 0
15521 or else Check_Derived_Type);
15522 end Derive_Subprograms;
15524 --------------------------------
15525 -- Derived_Standard_Character --
15526 --------------------------------
15528 procedure Derived_Standard_Character
15530 Parent_Type : Entity_Id;
15531 Derived_Type : Entity_Id)
15533 Loc : constant Source_Ptr := Sloc (N);
15534 Def : constant Node_Id := Type_Definition (N);
15535 Indic : constant Node_Id := Subtype_Indication (Def);
15536 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
15537 Implicit_Base : constant Entity_Id :=
15539 (E_Enumeration_Type, N, Derived_Type, 'B');
15545 Discard_Node (Process_Subtype (Indic, N));
15547 Set_Etype (Implicit_Base, Parent_Base);
15548 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
15549 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
15551 Set_Is_Character_Type (Implicit_Base, True);
15552 Set_Has_Delayed_Freeze (Implicit_Base);
15554 -- The bounds of the implicit base are the bounds of the parent base.
15555 -- Note that their type is the parent base.
15557 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
15558 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
15560 Set_Scalar_Range (Implicit_Base,
15563 High_Bound => Hi));
15565 Conditional_Delay (Derived_Type, Parent_Type);
15567 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
15568 Set_Etype (Derived_Type, Implicit_Base);
15569 Set_Size_Info (Derived_Type, Parent_Type);
15571 if Unknown_RM_Size (Derived_Type) then
15572 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
15575 Set_Is_Character_Type (Derived_Type, True);
15577 if Nkind (Indic) /= N_Subtype_Indication then
15579 -- If no explicit constraint, the bounds are those
15580 -- of the parent type.
15582 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
15583 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
15584 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
15587 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
15589 -- Because the implicit base is used in the conversion of the bounds, we
15590 -- have to freeze it now. This is similar to what is done for numeric
15591 -- types, and it equally suspicious, but otherwise a non-static bound
15592 -- will have a reference to an unfrozen type, which is rejected by Gigi
15593 -- (???). This requires specific care for definition of stream
15594 -- attributes. For details, see comments at the end of
15595 -- Build_Derived_Numeric_Type.
15597 Freeze_Before (N, Implicit_Base);
15598 end Derived_Standard_Character;
15600 ------------------------------
15601 -- Derived_Type_Declaration --
15602 ------------------------------
15604 procedure Derived_Type_Declaration
15607 Is_Completion : Boolean)
15609 Parent_Type : Entity_Id;
15611 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
15612 -- Check whether the parent type is a generic formal, or derives
15613 -- directly or indirectly from one.
15615 ------------------------
15616 -- Comes_From_Generic --
15617 ------------------------
15619 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
15621 if Is_Generic_Type (Typ) then
15624 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
15627 elsif Is_Private_Type (Typ)
15628 and then Present (Full_View (Typ))
15629 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
15633 elsif Is_Generic_Actual_Type (Typ) then
15639 end Comes_From_Generic;
15643 Def : constant Node_Id := Type_Definition (N);
15644 Iface_Def : Node_Id;
15645 Indic : constant Node_Id := Subtype_Indication (Def);
15646 Extension : constant Node_Id := Record_Extension_Part (Def);
15647 Parent_Node : Node_Id;
15650 -- Start of processing for Derived_Type_Declaration
15653 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
15655 -- Ada 2005 (AI-251): In case of interface derivation check that the
15656 -- parent is also an interface.
15658 if Interface_Present (Def) then
15659 Check_SPARK_05_Restriction ("interface is not allowed", Def);
15661 if not Is_Interface (Parent_Type) then
15662 Diagnose_Interface (Indic, Parent_Type);
15665 Parent_Node := Parent (Base_Type (Parent_Type));
15666 Iface_Def := Type_Definition (Parent_Node);
15668 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
15669 -- other limited interfaces.
15671 if Limited_Present (Def) then
15672 if Limited_Present (Iface_Def) then
15675 elsif Protected_Present (Iface_Def) then
15677 ("descendant of & must be declared as a protected "
15678 & "interface", N, Parent_Type);
15680 elsif Synchronized_Present (Iface_Def) then
15682 ("descendant of & must be declared as a synchronized "
15683 & "interface", N, Parent_Type);
15685 elsif Task_Present (Iface_Def) then
15687 ("descendant of & must be declared as a task interface",
15692 ("(Ada 2005) limited interface cannot inherit from "
15693 & "non-limited interface", Indic);
15696 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
15697 -- from non-limited or limited interfaces.
15699 elsif not Protected_Present (Def)
15700 and then not Synchronized_Present (Def)
15701 and then not Task_Present (Def)
15703 if Limited_Present (Iface_Def) then
15706 elsif Protected_Present (Iface_Def) then
15708 ("descendant of & must be declared as a protected "
15709 & "interface", N, Parent_Type);
15711 elsif Synchronized_Present (Iface_Def) then
15713 ("descendant of & must be declared as a synchronized "
15714 & "interface", N, Parent_Type);
15716 elsif Task_Present (Iface_Def) then
15718 ("descendant of & must be declared as a task interface",
15727 if Is_Tagged_Type (Parent_Type)
15728 and then Is_Concurrent_Type (Parent_Type)
15729 and then not Is_Interface (Parent_Type)
15732 ("parent type of a record extension cannot be a synchronized "
15733 & "tagged type (RM 3.9.1 (3/1))", N);
15734 Set_Etype (T, Any_Type);
15738 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
15741 if Is_Tagged_Type (Parent_Type)
15742 and then Is_Non_Empty_List (Interface_List (Def))
15749 Intf := First (Interface_List (Def));
15750 while Present (Intf) loop
15751 T := Find_Type_Of_Subtype_Indic (Intf);
15753 if not Is_Interface (T) then
15754 Diagnose_Interface (Intf, T);
15756 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
15757 -- a limited type from having a nonlimited progenitor.
15759 elsif (Limited_Present (Def)
15760 or else (not Is_Interface (Parent_Type)
15761 and then Is_Limited_Type (Parent_Type)))
15762 and then not Is_Limited_Interface (T)
15765 ("progenitor interface& of limited type must be limited",
15774 if Parent_Type = Any_Type
15775 or else Etype (Parent_Type) = Any_Type
15776 or else (Is_Class_Wide_Type (Parent_Type)
15777 and then Etype (Parent_Type) = T)
15779 -- If Parent_Type is undefined or illegal, make new type into a
15780 -- subtype of Any_Type, and set a few attributes to prevent cascaded
15781 -- errors. If this is a self-definition, emit error now.
15783 if T = Parent_Type or else T = Etype (Parent_Type) then
15784 Error_Msg_N ("type cannot be used in its own definition", Indic);
15787 Set_Ekind (T, Ekind (Parent_Type));
15788 Set_Etype (T, Any_Type);
15789 Set_Scalar_Range (T, Scalar_Range (Any_Type));
15791 if Is_Tagged_Type (T)
15792 and then Is_Record_Type (T)
15794 Set_Direct_Primitive_Operations (T, New_Elmt_List);
15800 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
15801 -- an interface is special because the list of interfaces in the full
15802 -- view can be given in any order. For example:
15804 -- type A is interface;
15805 -- type B is interface and A;
15806 -- type D is new B with private;
15808 -- type D is new A and B with null record; -- 1 --
15810 -- In this case we perform the following transformation of -1-:
15812 -- type D is new B and A with null record;
15814 -- If the parent of the full-view covers the parent of the partial-view
15815 -- we have two possible cases:
15817 -- 1) They have the same parent
15818 -- 2) The parent of the full-view implements some further interfaces
15820 -- In both cases we do not need to perform the transformation. In the
15821 -- first case the source program is correct and the transformation is
15822 -- not needed; in the second case the source program does not fulfill
15823 -- the no-hidden interfaces rule (AI-396) and the error will be reported
15826 -- This transformation not only simplifies the rest of the analysis of
15827 -- this type declaration but also simplifies the correct generation of
15828 -- the object layout to the expander.
15830 if In_Private_Part (Current_Scope)
15831 and then Is_Interface (Parent_Type)
15835 Partial_View : Entity_Id;
15836 Partial_View_Parent : Entity_Id;
15837 New_Iface : Node_Id;
15840 -- Look for the associated private type declaration
15842 Partial_View := First_Entity (Current_Scope);
15844 exit when No (Partial_View)
15845 or else (Has_Private_Declaration (Partial_View)
15846 and then Full_View (Partial_View) = T);
15848 Next_Entity (Partial_View);
15851 -- If the partial view was not found then the source code has
15852 -- errors and the transformation is not needed.
15854 if Present (Partial_View) then
15855 Partial_View_Parent := Etype (Partial_View);
15857 -- If the parent of the full-view covers the parent of the
15858 -- partial-view we have nothing else to do.
15860 if Interface_Present_In_Ancestor
15861 (Parent_Type, Partial_View_Parent)
15865 -- Traverse the list of interfaces of the full-view to look
15866 -- for the parent of the partial-view and perform the tree
15870 Iface := First (Interface_List (Def));
15871 while Present (Iface) loop
15872 if Etype (Iface) = Etype (Partial_View) then
15873 Rewrite (Subtype_Indication (Def),
15874 New_Copy (Subtype_Indication
15875 (Parent (Partial_View))));
15878 Make_Identifier (Sloc (N), Chars (Parent_Type));
15879 Append (New_Iface, Interface_List (Def));
15881 -- Analyze the transformed code
15883 Derived_Type_Declaration (T, N, Is_Completion);
15894 -- Only composite types other than array types are allowed to have
15897 if Present (Discriminant_Specifications (N)) then
15898 if (Is_Elementary_Type (Parent_Type)
15900 Is_Array_Type (Parent_Type))
15901 and then not Error_Posted (N)
15904 ("elementary or array type cannot have discriminants",
15905 Defining_Identifier (First (Discriminant_Specifications (N))));
15906 Set_Has_Discriminants (T, False);
15908 -- The type is allowed to have discriminants
15911 Check_SPARK_05_Restriction ("discriminant type is not allowed", N);
15915 -- In Ada 83, a derived type defined in a package specification cannot
15916 -- be used for further derivation until the end of its visible part.
15917 -- Note that derivation in the private part of the package is allowed.
15919 if Ada_Version = Ada_83
15920 and then Is_Derived_Type (Parent_Type)
15921 and then In_Visible_Part (Scope (Parent_Type))
15923 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
15925 ("(Ada 83): premature use of type for derivation", Indic);
15929 -- Check for early use of incomplete or private type
15931 if Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
15932 Error_Msg_N ("premature derivation of incomplete type", Indic);
15935 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
15936 and then not Comes_From_Generic (Parent_Type))
15937 or else Has_Private_Component (Parent_Type)
15939 -- The ancestor type of a formal type can be incomplete, in which
15940 -- case only the operations of the partial view are available in the
15941 -- generic. Subsequent checks may be required when the full view is
15942 -- analyzed to verify that a derivation from a tagged type has an
15945 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
15948 elsif No (Underlying_Type (Parent_Type))
15949 or else Has_Private_Component (Parent_Type)
15952 ("premature derivation of derived or private type", Indic);
15954 -- Flag the type itself as being in error, this prevents some
15955 -- nasty problems with subsequent uses of the malformed type.
15957 Set_Error_Posted (T);
15959 -- Check that within the immediate scope of an untagged partial
15960 -- view it's illegal to derive from the partial view if the
15961 -- full view is tagged. (7.3(7))
15963 -- We verify that the Parent_Type is a partial view by checking
15964 -- that it is not a Full_Type_Declaration (i.e. a private type or
15965 -- private extension declaration), to distinguish a partial view
15966 -- from a derivation from a private type which also appears as
15967 -- E_Private_Type. If the parent base type is not declared in an
15968 -- enclosing scope there is no need to check.
15970 elsif Present (Full_View (Parent_Type))
15971 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
15972 and then not Is_Tagged_Type (Parent_Type)
15973 and then Is_Tagged_Type (Full_View (Parent_Type))
15974 and then In_Open_Scopes (Scope (Base_Type (Parent_Type)))
15977 ("premature derivation from type with tagged full view",
15982 -- Check that form of derivation is appropriate
15984 Taggd := Is_Tagged_Type (Parent_Type);
15986 -- Set the parent type to the class-wide type's specific type in this
15987 -- case to prevent cascading errors
15989 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
15990 Error_Msg_N ("parent type must not be a class-wide type", Indic);
15991 Set_Etype (T, Etype (Parent_Type));
15995 if Present (Extension) and then not Taggd then
15997 ("type derived from untagged type cannot have extension", Indic);
15999 elsif No (Extension) and then Taggd then
16001 -- If this declaration is within a private part (or body) of a
16002 -- generic instantiation then the derivation is allowed (the parent
16003 -- type can only appear tagged in this case if it's a generic actual
16004 -- type, since it would otherwise have been rejected in the analysis
16005 -- of the generic template).
16007 if not Is_Generic_Actual_Type (Parent_Type)
16008 or else In_Visible_Part (Scope (Parent_Type))
16010 if Is_Class_Wide_Type (Parent_Type) then
16012 ("parent type must not be a class-wide type", Indic);
16014 -- Use specific type to prevent cascaded errors.
16016 Parent_Type := Etype (Parent_Type);
16020 ("type derived from tagged type must have extension", Indic);
16025 -- AI-443: Synchronized formal derived types require a private
16026 -- extension. There is no point in checking the ancestor type or
16027 -- the progenitors since the construct is wrong to begin with.
16029 if Ada_Version >= Ada_2005
16030 and then Is_Generic_Type (T)
16031 and then Present (Original_Node (N))
16034 Decl : constant Node_Id := Original_Node (N);
16037 if Nkind (Decl) = N_Formal_Type_Declaration
16038 and then Nkind (Formal_Type_Definition (Decl)) =
16039 N_Formal_Derived_Type_Definition
16040 and then Synchronized_Present (Formal_Type_Definition (Decl))
16041 and then No (Extension)
16043 -- Avoid emitting a duplicate error message
16045 and then not Error_Posted (Indic)
16048 ("synchronized derived type must have extension", N);
16053 if Null_Exclusion_Present (Def)
16054 and then not Is_Access_Type (Parent_Type)
16056 Error_Msg_N ("null exclusion can only apply to an access type", N);
16059 -- Avoid deriving parent primitives of underlying record views
16061 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
16062 Derive_Subps => not Is_Underlying_Record_View (T));
16064 -- AI-419: The parent type of an explicitly limited derived type must
16065 -- be a limited type or a limited interface.
16067 if Limited_Present (Def) then
16068 Set_Is_Limited_Record (T);
16070 if Is_Interface (T) then
16071 Set_Is_Limited_Interface (T);
16074 if not Is_Limited_Type (Parent_Type)
16076 (not Is_Interface (Parent_Type)
16077 or else not Is_Limited_Interface (Parent_Type))
16079 -- AI05-0096: a derivation in the private part of an instance is
16080 -- legal if the generic formal is untagged limited, and the actual
16083 if Is_Generic_Actual_Type (Parent_Type)
16084 and then In_Private_Part (Current_Scope)
16087 (Generic_Parent_Type (Parent (Parent_Type)))
16093 ("parent type& of limited type must be limited",
16099 -- In SPARK, there are no derived type definitions other than type
16100 -- extensions of tagged record types.
16102 if No (Extension) then
16103 Check_SPARK_05_Restriction
16104 ("derived type is not allowed", Original_Node (N));
16106 end Derived_Type_Declaration;
16108 ------------------------
16109 -- Diagnose_Interface --
16110 ------------------------
16112 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
16114 if not Is_Interface (E) and then E /= Any_Type then
16115 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
16117 end Diagnose_Interface;
16119 ----------------------------------
16120 -- Enumeration_Type_Declaration --
16121 ----------------------------------
16123 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
16130 -- Create identifier node representing lower bound
16132 B_Node := New_Node (N_Identifier, Sloc (Def));
16133 L := First (Literals (Def));
16134 Set_Chars (B_Node, Chars (L));
16135 Set_Entity (B_Node, L);
16136 Set_Etype (B_Node, T);
16137 Set_Is_Static_Expression (B_Node, True);
16139 R_Node := New_Node (N_Range, Sloc (Def));
16140 Set_Low_Bound (R_Node, B_Node);
16142 Set_Ekind (T, E_Enumeration_Type);
16143 Set_First_Literal (T, L);
16145 Set_Is_Constrained (T);
16149 -- Loop through literals of enumeration type setting pos and rep values
16150 -- except that if the Ekind is already set, then it means the literal
16151 -- was already constructed (case of a derived type declaration and we
16152 -- should not disturb the Pos and Rep values.
16154 while Present (L) loop
16155 if Ekind (L) /= E_Enumeration_Literal then
16156 Set_Ekind (L, E_Enumeration_Literal);
16157 Set_Enumeration_Pos (L, Ev);
16158 Set_Enumeration_Rep (L, Ev);
16159 Set_Is_Known_Valid (L, True);
16163 New_Overloaded_Entity (L);
16164 Generate_Definition (L);
16165 Set_Convention (L, Convention_Intrinsic);
16167 -- Case of character literal
16169 if Nkind (L) = N_Defining_Character_Literal then
16170 Set_Is_Character_Type (T, True);
16172 -- Check violation of No_Wide_Characters
16174 if Restriction_Check_Required (No_Wide_Characters) then
16175 Get_Name_String (Chars (L));
16177 if Name_Len >= 3 and then Name_Buffer (1 .. 2) = "QW" then
16178 Check_Restriction (No_Wide_Characters, L);
16187 -- Now create a node representing upper bound
16189 B_Node := New_Node (N_Identifier, Sloc (Def));
16190 Set_Chars (B_Node, Chars (Last (Literals (Def))));
16191 Set_Entity (B_Node, Last (Literals (Def)));
16192 Set_Etype (B_Node, T);
16193 Set_Is_Static_Expression (B_Node, True);
16195 Set_High_Bound (R_Node, B_Node);
16197 -- Initialize various fields of the type. Some of this information
16198 -- may be overwritten later through rep.clauses.
16200 Set_Scalar_Range (T, R_Node);
16201 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
16202 Set_Enum_Esize (T);
16203 Set_Enum_Pos_To_Rep (T, Empty);
16205 -- Set Discard_Names if configuration pragma set, or if there is
16206 -- a parameterless pragma in the current declarative region
16208 if Global_Discard_Names or else Discard_Names (Scope (T)) then
16209 Set_Discard_Names (T);
16212 -- Process end label if there is one
16214 if Present (Def) then
16215 Process_End_Label (Def, 'e', T);
16217 end Enumeration_Type_Declaration;
16219 ---------------------------------
16220 -- Expand_To_Stored_Constraint --
16221 ---------------------------------
16223 function Expand_To_Stored_Constraint
16225 Constraint : Elist_Id) return Elist_Id
16227 Explicitly_Discriminated_Type : Entity_Id;
16228 Expansion : Elist_Id;
16229 Discriminant : Entity_Id;
16231 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
16232 -- Find the nearest type that actually specifies discriminants
16234 ---------------------------------
16235 -- Type_With_Explicit_Discrims --
16236 ---------------------------------
16238 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
16239 Typ : constant E := Base_Type (Id);
16242 if Ekind (Typ) in Incomplete_Or_Private_Kind then
16243 if Present (Full_View (Typ)) then
16244 return Type_With_Explicit_Discrims (Full_View (Typ));
16248 if Has_Discriminants (Typ) then
16253 if Etype (Typ) = Typ then
16255 elsif Has_Discriminants (Typ) then
16258 return Type_With_Explicit_Discrims (Etype (Typ));
16261 end Type_With_Explicit_Discrims;
16263 -- Start of processing for Expand_To_Stored_Constraint
16266 if No (Constraint) or else Is_Empty_Elmt_List (Constraint) then
16270 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
16272 if No (Explicitly_Discriminated_Type) then
16276 Expansion := New_Elmt_List;
16279 First_Stored_Discriminant (Explicitly_Discriminated_Type);
16280 while Present (Discriminant) loop
16282 (Get_Discriminant_Value
16283 (Discriminant, Explicitly_Discriminated_Type, Constraint),
16285 Next_Stored_Discriminant (Discriminant);
16289 end Expand_To_Stored_Constraint;
16291 ---------------------------
16292 -- Find_Hidden_Interface --
16293 ---------------------------
16295 function Find_Hidden_Interface
16297 Dest : Elist_Id) return Entity_Id
16300 Iface_Elmt : Elmt_Id;
16303 if Present (Src) and then Present (Dest) then
16304 Iface_Elmt := First_Elmt (Src);
16305 while Present (Iface_Elmt) loop
16306 Iface := Node (Iface_Elmt);
16308 if Is_Interface (Iface)
16309 and then not Contain_Interface (Iface, Dest)
16314 Next_Elmt (Iface_Elmt);
16319 end Find_Hidden_Interface;
16321 --------------------
16322 -- Find_Type_Name --
16323 --------------------
16325 function Find_Type_Name (N : Node_Id) return Entity_Id is
16326 Id : constant Entity_Id := Defining_Identifier (N);
16328 New_Id : Entity_Id;
16329 Prev_Par : Node_Id;
16331 procedure Check_Duplicate_Aspects;
16332 -- Check that aspects specified in a completion have not been specified
16333 -- already in the partial view. Type_Invariant and others can be
16334 -- specified on either view but never on both.
16336 procedure Tag_Mismatch;
16337 -- Diagnose a tagged partial view whose full view is untagged.
16338 -- We post the message on the full view, with a reference to
16339 -- the previous partial view. The partial view can be private
16340 -- or incomplete, and these are handled in a different manner,
16341 -- so we determine the position of the error message from the
16342 -- respective slocs of both.
16344 -----------------------------
16345 -- Check_Duplicate_Aspects --
16346 -----------------------------
16348 procedure Check_Duplicate_Aspects is
16349 Prev_Aspects : constant List_Id := Aspect_Specifications (Prev_Par);
16350 Full_Aspects : constant List_Id := Aspect_Specifications (N);
16351 F_Spec, P_Spec : Node_Id;
16354 if Present (Full_Aspects) then
16355 F_Spec := First (Full_Aspects);
16356 while Present (F_Spec) loop
16357 if Present (Prev_Aspects) then
16358 P_Spec := First (Prev_Aspects);
16359 while Present (P_Spec) loop
16360 if Chars (Identifier (P_Spec)) =
16361 Chars (Identifier (F_Spec))
16364 ("aspect already specified in private declaration",
16374 if Has_Discriminants (Prev)
16375 and then not Has_Unknown_Discriminants (Prev)
16376 and then Chars (Identifier (F_Spec)) =
16377 Name_Implicit_Dereference
16379 Error_Msg_N ("cannot specify aspect " &
16380 "if partial view has known discriminants", F_Spec);
16386 end Check_Duplicate_Aspects;
16392 procedure Tag_Mismatch is
16394 if Sloc (Prev) < Sloc (Id) then
16395 if Ada_Version >= Ada_2012
16396 and then Nkind (N) = N_Private_Type_Declaration
16399 ("declaration of private } must be a tagged type ", Id, Prev);
16402 ("full declaration of } must be a tagged type ", Id, Prev);
16406 if Ada_Version >= Ada_2012
16407 and then Nkind (N) = N_Private_Type_Declaration
16410 ("declaration of private } must be a tagged type ", Prev, Id);
16413 ("full declaration of } must be a tagged type ", Prev, Id);
16418 -- Start of processing for Find_Type_Name
16421 -- Find incomplete declaration, if one was given
16423 Prev := Current_Entity_In_Scope (Id);
16425 -- New type declaration
16431 -- Previous declaration exists
16434 Prev_Par := Parent (Prev);
16436 -- Error if not incomplete/private case except if previous
16437 -- declaration is implicit, etc. Enter_Name will emit error if
16440 if not Is_Incomplete_Or_Private_Type (Prev) then
16444 -- Check invalid completion of private or incomplete type
16446 elsif not Nkind_In (N, N_Full_Type_Declaration,
16447 N_Task_Type_Declaration,
16448 N_Protected_Type_Declaration)
16450 (Ada_Version < Ada_2012
16451 or else not Is_Incomplete_Type (Prev)
16452 or else not Nkind_In (N, N_Private_Type_Declaration,
16453 N_Private_Extension_Declaration))
16455 -- Completion must be a full type declarations (RM 7.3(4))
16457 Error_Msg_Sloc := Sloc (Prev);
16458 Error_Msg_NE ("invalid completion of }", Id, Prev);
16460 -- Set scope of Id to avoid cascaded errors. Entity is never
16461 -- examined again, except when saving globals in generics.
16463 Set_Scope (Id, Current_Scope);
16466 -- If this is a repeated incomplete declaration, no further
16467 -- checks are possible.
16469 if Nkind (N) = N_Incomplete_Type_Declaration then
16473 -- Case of full declaration of incomplete type
16475 elsif Ekind (Prev) = E_Incomplete_Type
16476 and then (Ada_Version < Ada_2012
16477 or else No (Full_View (Prev))
16478 or else not Is_Private_Type (Full_View (Prev)))
16480 -- Indicate that the incomplete declaration has a matching full
16481 -- declaration. The defining occurrence of the incomplete
16482 -- declaration remains the visible one, and the procedure
16483 -- Get_Full_View dereferences it whenever the type is used.
16485 if Present (Full_View (Prev)) then
16486 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
16489 Set_Full_View (Prev, Id);
16490 Append_Entity (Id, Current_Scope);
16491 Set_Is_Public (Id, Is_Public (Prev));
16492 Set_Is_Internal (Id);
16495 -- If the incomplete view is tagged, a class_wide type has been
16496 -- created already. Use it for the private type as well, in order
16497 -- to prevent multiple incompatible class-wide types that may be
16498 -- created for self-referential anonymous access components.
16500 if Is_Tagged_Type (Prev)
16501 and then Present (Class_Wide_Type (Prev))
16503 Set_Ekind (Id, Ekind (Prev)); -- will be reset later
16504 Set_Class_Wide_Type (Id, Class_Wide_Type (Prev));
16506 -- The type of the classwide type is the current Id. Previously
16507 -- this was not done for private declarations because of order-
16508 -- of elaboration issues in the back-end, but gigi now handles
16511 Set_Etype (Class_Wide_Type (Id), Id);
16514 -- Case of full declaration of private type
16517 -- If the private type was a completion of an incomplete type then
16518 -- update Prev to reference the private type
16520 if Ada_Version >= Ada_2012
16521 and then Ekind (Prev) = E_Incomplete_Type
16522 and then Present (Full_View (Prev))
16523 and then Is_Private_Type (Full_View (Prev))
16525 Prev := Full_View (Prev);
16526 Prev_Par := Parent (Prev);
16529 if Nkind (N) = N_Full_Type_Declaration
16531 (Type_Definition (N), N_Record_Definition,
16532 N_Derived_Type_Definition)
16533 and then Interface_Present (Type_Definition (N))
16536 ("completion of private type cannot be an interface", N);
16539 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
16540 if Etype (Prev) /= Prev then
16542 -- Prev is a private subtype or a derived type, and needs
16545 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
16548 elsif Ekind (Prev) = E_Private_Type
16549 and then Nkind_In (N, N_Task_Type_Declaration,
16550 N_Protected_Type_Declaration)
16553 ("completion of nonlimited type cannot be limited", N);
16555 elsif Ekind (Prev) = E_Record_Type_With_Private
16556 and then Nkind_In (N, N_Task_Type_Declaration,
16557 N_Protected_Type_Declaration)
16559 if not Is_Limited_Record (Prev) then
16561 ("completion of nonlimited type cannot be limited", N);
16563 elsif No (Interface_List (N)) then
16565 ("completion of tagged private type must be tagged",
16570 -- Ada 2005 (AI-251): Private extension declaration of a task
16571 -- type or a protected type. This case arises when covering
16572 -- interface types.
16574 elsif Nkind_In (N, N_Task_Type_Declaration,
16575 N_Protected_Type_Declaration)
16579 elsif Nkind (N) /= N_Full_Type_Declaration
16580 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
16583 ("full view of private extension must be an extension", N);
16585 elsif not (Abstract_Present (Parent (Prev)))
16586 and then Abstract_Present (Type_Definition (N))
16589 ("full view of non-abstract extension cannot be abstract", N);
16592 if not In_Private_Part (Current_Scope) then
16594 ("declaration of full view must appear in private part", N);
16597 if Ada_Version >= Ada_2012 then
16598 Check_Duplicate_Aspects;
16601 Copy_And_Swap (Prev, Id);
16602 Set_Has_Private_Declaration (Prev);
16603 Set_Has_Private_Declaration (Id);
16605 -- AI12-0133: Indicate whether we have a partial view with
16606 -- unknown discriminants, in which case initialization of objects
16607 -- of the type do not receive an invariant check.
16609 Set_Partial_View_Has_Unknown_Discr
16610 (Prev, Has_Unknown_Discriminants (Id));
16612 -- Preserve aspect and iterator flags that may have been set on
16613 -- the partial view.
16615 Set_Has_Delayed_Aspects (Prev, Has_Delayed_Aspects (Id));
16616 Set_Has_Implicit_Dereference (Prev, Has_Implicit_Dereference (Id));
16618 -- If no error, propagate freeze_node from private to full view.
16619 -- It may have been generated for an early operational item.
16621 if Present (Freeze_Node (Id))
16622 and then Serious_Errors_Detected = 0
16623 and then No (Full_View (Id))
16625 Set_Freeze_Node (Prev, Freeze_Node (Id));
16626 Set_Freeze_Node (Id, Empty);
16627 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
16630 Set_Full_View (Id, Prev);
16634 -- Verify that full declaration conforms to partial one
16636 if Is_Incomplete_Or_Private_Type (Prev)
16637 and then Present (Discriminant_Specifications (Prev_Par))
16639 if Present (Discriminant_Specifications (N)) then
16640 if Ekind (Prev) = E_Incomplete_Type then
16641 Check_Discriminant_Conformance (N, Prev, Prev);
16643 Check_Discriminant_Conformance (N, Prev, Id);
16648 ("missing discriminants in full type declaration", N);
16650 -- To avoid cascaded errors on subsequent use, share the
16651 -- discriminants of the partial view.
16653 Set_Discriminant_Specifications (N,
16654 Discriminant_Specifications (Prev_Par));
16658 -- A prior untagged partial view can have an associated class-wide
16659 -- type due to use of the class attribute, and in this case the full
16660 -- type must also be tagged. This Ada 95 usage is deprecated in favor
16661 -- of incomplete tagged declarations, but we check for it.
16664 and then (Is_Tagged_Type (Prev)
16665 or else Present (Class_Wide_Type (Prev)))
16667 -- Ada 2012 (AI05-0162): A private type may be the completion of
16668 -- an incomplete type.
16670 if Ada_Version >= Ada_2012
16671 and then Is_Incomplete_Type (Prev)
16672 and then Nkind_In (N, N_Private_Type_Declaration,
16673 N_Private_Extension_Declaration)
16675 -- No need to check private extensions since they are tagged
16677 if Nkind (N) = N_Private_Type_Declaration
16678 and then not Tagged_Present (N)
16683 -- The full declaration is either a tagged type (including
16684 -- a synchronized type that implements interfaces) or a
16685 -- type extension, otherwise this is an error.
16687 elsif Nkind_In (N, N_Task_Type_Declaration,
16688 N_Protected_Type_Declaration)
16690 if No (Interface_List (N)) and then not Error_Posted (N) then
16694 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
16696 -- Indicate that the previous declaration (tagged incomplete
16697 -- or private declaration) requires the same on the full one.
16699 if not Tagged_Present (Type_Definition (N)) then
16701 Set_Is_Tagged_Type (Id);
16704 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
16705 if No (Record_Extension_Part (Type_Definition (N))) then
16707 ("full declaration of } must be a record extension",
16710 -- Set some attributes to produce a usable full view
16712 Set_Is_Tagged_Type (Id);
16721 and then Nkind (Parent (Prev)) = N_Incomplete_Type_Declaration
16722 and then Present (Premature_Use (Parent (Prev)))
16724 Error_Msg_Sloc := Sloc (N);
16726 ("\full declaration #", Premature_Use (Parent (Prev)));
16731 end Find_Type_Name;
16733 -------------------------
16734 -- Find_Type_Of_Object --
16735 -------------------------
16737 function Find_Type_Of_Object
16738 (Obj_Def : Node_Id;
16739 Related_Nod : Node_Id) return Entity_Id
16741 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
16742 P : Node_Id := Parent (Obj_Def);
16747 -- If the parent is a component_definition node we climb to the
16748 -- component_declaration node
16750 if Nkind (P) = N_Component_Definition then
16754 -- Case of an anonymous array subtype
16756 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
16757 N_Unconstrained_Array_Definition)
16760 Array_Type_Declaration (T, Obj_Def);
16762 -- Create an explicit subtype whenever possible
16764 elsif Nkind (P) /= N_Component_Declaration
16765 and then Def_Kind = N_Subtype_Indication
16767 -- Base name of subtype on object name, which will be unique in
16768 -- the current scope.
16770 -- If this is a duplicate declaration, return base type, to avoid
16771 -- generating duplicate anonymous types.
16773 if Error_Posted (P) then
16774 Analyze (Subtype_Mark (Obj_Def));
16775 return Entity (Subtype_Mark (Obj_Def));
16780 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
16782 T := Make_Defining_Identifier (Sloc (P), Nam);
16784 Insert_Action (Obj_Def,
16785 Make_Subtype_Declaration (Sloc (P),
16786 Defining_Identifier => T,
16787 Subtype_Indication => Relocate_Node (Obj_Def)));
16789 -- This subtype may need freezing, and this will not be done
16790 -- automatically if the object declaration is not in declarative
16791 -- part. Since this is an object declaration, the type cannot always
16792 -- be frozen here. Deferred constants do not freeze their type
16793 -- (which often enough will be private).
16795 if Nkind (P) = N_Object_Declaration
16796 and then Constant_Present (P)
16797 and then No (Expression (P))
16801 -- Here we freeze the base type of object type to catch premature use
16802 -- of discriminated private type without a full view.
16805 Insert_Actions (Obj_Def, Freeze_Entity (Base_Type (T), P));
16808 -- Ada 2005 AI-406: the object definition in an object declaration
16809 -- can be an access definition.
16811 elsif Def_Kind = N_Access_Definition then
16812 T := Access_Definition (Related_Nod, Obj_Def);
16814 Set_Is_Local_Anonymous_Access
16816 V => (Ada_Version < Ada_2012)
16817 or else (Nkind (P) /= N_Object_Declaration)
16818 or else Is_Library_Level_Entity (Defining_Identifier (P)));
16820 -- Otherwise, the object definition is just a subtype_mark
16823 T := Process_Subtype (Obj_Def, Related_Nod);
16825 -- If expansion is disabled an object definition that is an aggregate
16826 -- will not get expanded and may lead to scoping problems in the back
16827 -- end, if the object is referenced in an inner scope. In that case
16828 -- create an itype reference for the object definition now. This
16829 -- may be redundant in some cases, but harmless.
16832 and then Nkind (Related_Nod) = N_Object_Declaration
16835 Build_Itype_Reference (T, Related_Nod);
16840 end Find_Type_Of_Object;
16842 --------------------------------
16843 -- Find_Type_Of_Subtype_Indic --
16844 --------------------------------
16846 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
16850 -- Case of subtype mark with a constraint
16852 if Nkind (S) = N_Subtype_Indication then
16853 Find_Type (Subtype_Mark (S));
16854 Typ := Entity (Subtype_Mark (S));
16857 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
16860 ("incorrect constraint for this kind of type", Constraint (S));
16861 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
16864 -- Otherwise we have a subtype mark without a constraint
16866 elsif Error_Posted (S) then
16867 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
16875 -- Check No_Wide_Characters restriction
16877 Check_Wide_Character_Restriction (Typ, S);
16880 end Find_Type_Of_Subtype_Indic;
16882 -------------------------------------
16883 -- Floating_Point_Type_Declaration --
16884 -------------------------------------
16886 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
16887 Digs : constant Node_Id := Digits_Expression (Def);
16888 Max_Digs_Val : constant Uint := Digits_Value (Standard_Long_Long_Float);
16890 Base_Typ : Entity_Id;
16891 Implicit_Base : Entity_Id;
16894 function Can_Derive_From (E : Entity_Id) return Boolean;
16895 -- Find if given digits value, and possibly a specified range, allows
16896 -- derivation from specified type
16898 function Find_Base_Type return Entity_Id;
16899 -- Find a predefined base type that Def can derive from, or generate
16900 -- an error and substitute Long_Long_Float if none exists.
16902 ---------------------
16903 -- Can_Derive_From --
16904 ---------------------
16906 function Can_Derive_From (E : Entity_Id) return Boolean is
16907 Spec : constant Entity_Id := Real_Range_Specification (Def);
16910 -- Check specified "digits" constraint
16912 if Digs_Val > Digits_Value (E) then
16916 -- Check for matching range, if specified
16918 if Present (Spec) then
16919 if Expr_Value_R (Type_Low_Bound (E)) >
16920 Expr_Value_R (Low_Bound (Spec))
16925 if Expr_Value_R (Type_High_Bound (E)) <
16926 Expr_Value_R (High_Bound (Spec))
16933 end Can_Derive_From;
16935 --------------------
16936 -- Find_Base_Type --
16937 --------------------
16939 function Find_Base_Type return Entity_Id is
16940 Choice : Elmt_Id := First_Elmt (Predefined_Float_Types);
16943 -- Iterate over the predefined types in order, returning the first
16944 -- one that Def can derive from.
16946 while Present (Choice) loop
16947 if Can_Derive_From (Node (Choice)) then
16948 return Node (Choice);
16951 Next_Elmt (Choice);
16954 -- If we can't derive from any existing type, use Long_Long_Float
16955 -- and give appropriate message explaining the problem.
16957 if Digs_Val > Max_Digs_Val then
16958 -- It might be the case that there is a type with the requested
16959 -- range, just not the combination of digits and range.
16962 ("no predefined type has requested range and precision",
16963 Real_Range_Specification (Def));
16967 ("range too large for any predefined type",
16968 Real_Range_Specification (Def));
16971 return Standard_Long_Long_Float;
16972 end Find_Base_Type;
16974 -- Start of processing for Floating_Point_Type_Declaration
16977 Check_Restriction (No_Floating_Point, Def);
16979 -- Create an implicit base type
16982 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
16984 -- Analyze and verify digits value
16986 Analyze_And_Resolve (Digs, Any_Integer);
16987 Check_Digits_Expression (Digs);
16988 Digs_Val := Expr_Value (Digs);
16990 -- Process possible range spec and find correct type to derive from
16992 Process_Real_Range_Specification (Def);
16994 -- Check that requested number of digits is not too high.
16996 if Digs_Val > Max_Digs_Val then
16998 -- The check for Max_Base_Digits may be somewhat expensive, as it
16999 -- requires reading System, so only do it when necessary.
17002 Max_Base_Digits : constant Uint :=
17005 (Parent (RTE (RE_Max_Base_Digits))));
17008 if Digs_Val > Max_Base_Digits then
17009 Error_Msg_Uint_1 := Max_Base_Digits;
17010 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
17012 elsif No (Real_Range_Specification (Def)) then
17013 Error_Msg_Uint_1 := Max_Digs_Val;
17014 Error_Msg_N ("types with more than ^ digits need range spec "
17015 & "(RM 3.5.7(6))", Digs);
17020 -- Find a suitable type to derive from or complain and use a substitute
17022 Base_Typ := Find_Base_Type;
17024 -- If there are bounds given in the declaration use them as the bounds
17025 -- of the type, otherwise use the bounds of the predefined base type
17026 -- that was chosen based on the Digits value.
17028 if Present (Real_Range_Specification (Def)) then
17029 Set_Scalar_Range (T, Real_Range_Specification (Def));
17030 Set_Is_Constrained (T);
17032 -- The bounds of this range must be converted to machine numbers
17033 -- in accordance with RM 4.9(38).
17035 Bound := Type_Low_Bound (T);
17037 if Nkind (Bound) = N_Real_Literal then
17039 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
17040 Set_Is_Machine_Number (Bound);
17043 Bound := Type_High_Bound (T);
17045 if Nkind (Bound) = N_Real_Literal then
17047 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
17048 Set_Is_Machine_Number (Bound);
17052 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
17055 -- Complete definition of implicit base and declared first subtype. The
17056 -- inheritance of the rep item chain ensures that SPARK-related pragmas
17057 -- are not clobbered when the floating point type acts as a full view of
17060 Set_Etype (Implicit_Base, Base_Typ);
17061 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
17062 Set_Size_Info (Implicit_Base, Base_Typ);
17063 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
17064 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
17065 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
17066 Set_Float_Rep (Implicit_Base, Float_Rep (Base_Typ));
17068 Set_Ekind (T, E_Floating_Point_Subtype);
17069 Set_Etype (T, Implicit_Base);
17070 Set_Size_Info (T, Implicit_Base);
17071 Set_RM_Size (T, RM_Size (Implicit_Base));
17072 Inherit_Rep_Item_Chain (T, Implicit_Base);
17073 Set_Digits_Value (T, Digs_Val);
17074 end Floating_Point_Type_Declaration;
17076 ----------------------------
17077 -- Get_Discriminant_Value --
17078 ----------------------------
17080 -- This is the situation:
17082 -- There is a non-derived type
17084 -- type T0 (Dx, Dy, Dz...)
17086 -- There are zero or more levels of derivation, with each derivation
17087 -- either purely inheriting the discriminants, or defining its own.
17089 -- type Ti is new Ti-1
17091 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
17093 -- subtype Ti is ...
17095 -- The subtype issue is avoided by the use of Original_Record_Component,
17096 -- and the fact that derived subtypes also derive the constraints.
17098 -- This chain leads back from
17100 -- Typ_For_Constraint
17102 -- Typ_For_Constraint has discriminants, and the value for each
17103 -- discriminant is given by its corresponding Elmt of Constraints.
17105 -- Discriminant is some discriminant in this hierarchy
17107 -- We need to return its value
17109 -- We do this by recursively searching each level, and looking for
17110 -- Discriminant. Once we get to the bottom, we start backing up
17111 -- returning the value for it which may in turn be a discriminant
17112 -- further up, so on the backup we continue the substitution.
17114 function Get_Discriminant_Value
17115 (Discriminant : Entity_Id;
17116 Typ_For_Constraint : Entity_Id;
17117 Constraint : Elist_Id) return Node_Id
17119 function Root_Corresponding_Discriminant
17120 (Discr : Entity_Id) return Entity_Id;
17121 -- Given a discriminant, traverse the chain of inherited discriminants
17122 -- and return the topmost discriminant.
17124 function Search_Derivation_Levels
17126 Discrim_Values : Elist_Id;
17127 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
17128 -- This is the routine that performs the recursive search of levels
17129 -- as described above.
17131 -------------------------------------
17132 -- Root_Corresponding_Discriminant --
17133 -------------------------------------
17135 function Root_Corresponding_Discriminant
17136 (Discr : Entity_Id) return Entity_Id
17142 while Present (Corresponding_Discriminant (D)) loop
17143 D := Corresponding_Discriminant (D);
17147 end Root_Corresponding_Discriminant;
17149 ------------------------------
17150 -- Search_Derivation_Levels --
17151 ------------------------------
17153 function Search_Derivation_Levels
17155 Discrim_Values : Elist_Id;
17156 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
17160 Result : Node_Or_Entity_Id;
17161 Result_Entity : Node_Id;
17164 -- If inappropriate type, return Error, this happens only in
17165 -- cascaded error situations, and we want to avoid a blow up.
17167 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
17171 -- Look deeper if possible. Use Stored_Constraints only for
17172 -- untagged types. For tagged types use the given constraint.
17173 -- This asymmetry needs explanation???
17175 if not Stored_Discrim_Values
17176 and then Present (Stored_Constraint (Ti))
17177 and then not Is_Tagged_Type (Ti)
17180 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
17183 Td : constant Entity_Id := Etype (Ti);
17187 Result := Discriminant;
17190 if Present (Stored_Constraint (Ti)) then
17192 Search_Derivation_Levels
17193 (Td, Stored_Constraint (Ti), True);
17196 Search_Derivation_Levels
17197 (Td, Discrim_Values, Stored_Discrim_Values);
17203 -- Extra underlying places to search, if not found above. For
17204 -- concurrent types, the relevant discriminant appears in the
17205 -- corresponding record. For a type derived from a private type
17206 -- without discriminant, the full view inherits the discriminants
17207 -- of the full view of the parent.
17209 if Result = Discriminant then
17210 if Is_Concurrent_Type (Ti)
17211 and then Present (Corresponding_Record_Type (Ti))
17214 Search_Derivation_Levels (
17215 Corresponding_Record_Type (Ti),
17217 Stored_Discrim_Values);
17219 elsif Is_Private_Type (Ti)
17220 and then not Has_Discriminants (Ti)
17221 and then Present (Full_View (Ti))
17222 and then Etype (Full_View (Ti)) /= Ti
17225 Search_Derivation_Levels (
17228 Stored_Discrim_Values);
17232 -- If Result is not a (reference to a) discriminant, return it,
17233 -- otherwise set Result_Entity to the discriminant.
17235 if Nkind (Result) = N_Defining_Identifier then
17236 pragma Assert (Result = Discriminant);
17237 Result_Entity := Result;
17240 if not Denotes_Discriminant (Result) then
17244 Result_Entity := Entity (Result);
17247 -- See if this level of derivation actually has discriminants because
17248 -- tagged derivations can add them, hence the lower levels need not
17251 if not Has_Discriminants (Ti) then
17255 -- Scan Ti's discriminants for Result_Entity, and return its
17256 -- corresponding value, if any.
17258 Result_Entity := Original_Record_Component (Result_Entity);
17260 Assoc := First_Elmt (Discrim_Values);
17262 if Stored_Discrim_Values then
17263 Disc := First_Stored_Discriminant (Ti);
17265 Disc := First_Discriminant (Ti);
17268 while Present (Disc) loop
17269 pragma Assert (Present (Assoc));
17271 if Original_Record_Component (Disc) = Result_Entity then
17272 return Node (Assoc);
17277 if Stored_Discrim_Values then
17278 Next_Stored_Discriminant (Disc);
17280 Next_Discriminant (Disc);
17284 -- Could not find it
17287 end Search_Derivation_Levels;
17291 Result : Node_Or_Entity_Id;
17293 -- Start of processing for Get_Discriminant_Value
17296 -- ??? This routine is a gigantic mess and will be deleted. For the
17297 -- time being just test for the trivial case before calling recurse.
17299 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
17305 D := First_Discriminant (Typ_For_Constraint);
17306 E := First_Elmt (Constraint);
17307 while Present (D) loop
17308 if Chars (D) = Chars (Discriminant) then
17312 Next_Discriminant (D);
17318 Result := Search_Derivation_Levels
17319 (Typ_For_Constraint, Constraint, False);
17321 -- ??? hack to disappear when this routine is gone
17323 if Nkind (Result) = N_Defining_Identifier then
17329 D := First_Discriminant (Typ_For_Constraint);
17330 E := First_Elmt (Constraint);
17331 while Present (D) loop
17332 if Root_Corresponding_Discriminant (D) = Discriminant then
17336 Next_Discriminant (D);
17342 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
17344 end Get_Discriminant_Value;
17346 --------------------------
17347 -- Has_Range_Constraint --
17348 --------------------------
17350 function Has_Range_Constraint (N : Node_Id) return Boolean is
17351 C : constant Node_Id := Constraint (N);
17354 if Nkind (C) = N_Range_Constraint then
17357 elsif Nkind (C) = N_Digits_Constraint then
17359 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
17360 or else Present (Range_Constraint (C));
17362 elsif Nkind (C) = N_Delta_Constraint then
17363 return Present (Range_Constraint (C));
17368 end Has_Range_Constraint;
17370 ------------------------
17371 -- Inherit_Components --
17372 ------------------------
17374 function Inherit_Components
17376 Parent_Base : Entity_Id;
17377 Derived_Base : Entity_Id;
17378 Is_Tagged : Boolean;
17379 Inherit_Discr : Boolean;
17380 Discs : Elist_Id) return Elist_Id
17382 Assoc_List : constant Elist_Id := New_Elmt_List;
17384 procedure Inherit_Component
17385 (Old_C : Entity_Id;
17386 Plain_Discrim : Boolean := False;
17387 Stored_Discrim : Boolean := False);
17388 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
17389 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
17390 -- True, Old_C is a stored discriminant. If they are both false then
17391 -- Old_C is a regular component.
17393 -----------------------
17394 -- Inherit_Component --
17395 -----------------------
17397 procedure Inherit_Component
17398 (Old_C : Entity_Id;
17399 Plain_Discrim : Boolean := False;
17400 Stored_Discrim : Boolean := False)
17402 procedure Set_Anonymous_Type (Id : Entity_Id);
17403 -- Id denotes the entity of an access discriminant or anonymous
17404 -- access component. Set the type of Id to either the same type of
17405 -- Old_C or create a new one depending on whether the parent and
17406 -- the child types are in the same scope.
17408 ------------------------
17409 -- Set_Anonymous_Type --
17410 ------------------------
17412 procedure Set_Anonymous_Type (Id : Entity_Id) is
17413 Old_Typ : constant Entity_Id := Etype (Old_C);
17416 if Scope (Parent_Base) = Scope (Derived_Base) then
17417 Set_Etype (Id, Old_Typ);
17419 -- The parent and the derived type are in two different scopes.
17420 -- Reuse the type of the original discriminant / component by
17421 -- copying it in order to preserve all attributes.
17425 Typ : constant Entity_Id := New_Copy (Old_Typ);
17428 Set_Etype (Id, Typ);
17430 -- Since we do not generate component declarations for
17431 -- inherited components, associate the itype with the
17434 Set_Associated_Node_For_Itype (Typ, Parent (Derived_Base));
17435 Set_Scope (Typ, Derived_Base);
17438 end Set_Anonymous_Type;
17440 -- Local variables and constants
17442 New_C : constant Entity_Id := New_Copy (Old_C);
17444 Corr_Discrim : Entity_Id;
17445 Discrim : Entity_Id;
17447 -- Start of processing for Inherit_Component
17450 pragma Assert (not Is_Tagged or not Stored_Discrim);
17452 Set_Parent (New_C, Parent (Old_C));
17454 -- Regular discriminants and components must be inserted in the scope
17455 -- of the Derived_Base. Do it here.
17457 if not Stored_Discrim then
17458 Enter_Name (New_C);
17461 -- For tagged types the Original_Record_Component must point to
17462 -- whatever this field was pointing to in the parent type. This has
17463 -- already been achieved by the call to New_Copy above.
17465 if not Is_Tagged then
17466 Set_Original_Record_Component (New_C, New_C);
17469 -- Set the proper type of an access discriminant
17471 if Ekind (New_C) = E_Discriminant
17472 and then Ekind (Etype (New_C)) = E_Anonymous_Access_Type
17474 Set_Anonymous_Type (New_C);
17477 -- If we have inherited a component then see if its Etype contains
17478 -- references to Parent_Base discriminants. In this case, replace
17479 -- these references with the constraints given in Discs. We do not
17480 -- do this for the partial view of private types because this is
17481 -- not needed (only the components of the full view will be used
17482 -- for code generation) and cause problem. We also avoid this
17483 -- transformation in some error situations.
17485 if Ekind (New_C) = E_Component then
17487 -- Set the proper type of an anonymous access component
17489 if Ekind (Etype (New_C)) = E_Anonymous_Access_Type then
17490 Set_Anonymous_Type (New_C);
17492 elsif (Is_Private_Type (Derived_Base)
17493 and then not Is_Generic_Type (Derived_Base))
17494 or else (Is_Empty_Elmt_List (Discs)
17495 and then not Expander_Active)
17497 Set_Etype (New_C, Etype (Old_C));
17500 -- The current component introduces a circularity of the
17503 -- limited with Pack_2;
17504 -- package Pack_1 is
17505 -- type T_1 is tagged record
17506 -- Comp : access Pack_2.T_2;
17512 -- package Pack_2 is
17513 -- type T_2 is new Pack_1.T_1 with ...;
17518 Constrain_Component_Type
17519 (Old_C, Derived_Base, N, Parent_Base, Discs));
17523 -- In derived tagged types it is illegal to reference a non
17524 -- discriminant component in the parent type. To catch this, mark
17525 -- these components with an Ekind of E_Void. This will be reset in
17526 -- Record_Type_Definition after processing the record extension of
17527 -- the derived type.
17529 -- If the declaration is a private extension, there is no further
17530 -- record extension to process, and the components retain their
17531 -- current kind, because they are visible at this point.
17533 if Is_Tagged and then Ekind (New_C) = E_Component
17534 and then Nkind (N) /= N_Private_Extension_Declaration
17536 Set_Ekind (New_C, E_Void);
17539 if Plain_Discrim then
17540 Set_Corresponding_Discriminant (New_C, Old_C);
17541 Build_Discriminal (New_C);
17543 -- If we are explicitly inheriting a stored discriminant it will be
17544 -- completely hidden.
17546 elsif Stored_Discrim then
17547 Set_Corresponding_Discriminant (New_C, Empty);
17548 Set_Discriminal (New_C, Empty);
17549 Set_Is_Completely_Hidden (New_C);
17551 -- Set the Original_Record_Component of each discriminant in the
17552 -- derived base to point to the corresponding stored that we just
17555 Discrim := First_Discriminant (Derived_Base);
17556 while Present (Discrim) loop
17557 Corr_Discrim := Corresponding_Discriminant (Discrim);
17559 -- Corr_Discrim could be missing in an error situation
17561 if Present (Corr_Discrim)
17562 and then Original_Record_Component (Corr_Discrim) = Old_C
17564 Set_Original_Record_Component (Discrim, New_C);
17567 Next_Discriminant (Discrim);
17570 Append_Entity (New_C, Derived_Base);
17573 if not Is_Tagged then
17574 Append_Elmt (Old_C, Assoc_List);
17575 Append_Elmt (New_C, Assoc_List);
17577 end Inherit_Component;
17579 -- Variables local to Inherit_Component
17581 Loc : constant Source_Ptr := Sloc (N);
17583 Parent_Discrim : Entity_Id;
17584 Stored_Discrim : Entity_Id;
17586 Component : Entity_Id;
17588 -- Start of processing for Inherit_Components
17591 if not Is_Tagged then
17592 Append_Elmt (Parent_Base, Assoc_List);
17593 Append_Elmt (Derived_Base, Assoc_List);
17596 -- Inherit parent discriminants if needed
17598 if Inherit_Discr then
17599 Parent_Discrim := First_Discriminant (Parent_Base);
17600 while Present (Parent_Discrim) loop
17601 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
17602 Next_Discriminant (Parent_Discrim);
17606 -- Create explicit stored discrims for untagged types when necessary
17608 if not Has_Unknown_Discriminants (Derived_Base)
17609 and then Has_Discriminants (Parent_Base)
17610 and then not Is_Tagged
17613 or else First_Discriminant (Parent_Base) /=
17614 First_Stored_Discriminant (Parent_Base))
17616 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
17617 while Present (Stored_Discrim) loop
17618 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
17619 Next_Stored_Discriminant (Stored_Discrim);
17623 -- See if we can apply the second transformation for derived types, as
17624 -- explained in point 6. in the comments above Build_Derived_Record_Type
17625 -- This is achieved by appending Derived_Base discriminants into Discs,
17626 -- which has the side effect of returning a non empty Discs list to the
17627 -- caller of Inherit_Components, which is what we want. This must be
17628 -- done for private derived types if there are explicit stored
17629 -- discriminants, to ensure that we can retrieve the values of the
17630 -- constraints provided in the ancestors.
17633 and then Is_Empty_Elmt_List (Discs)
17634 and then Present (First_Discriminant (Derived_Base))
17636 (not Is_Private_Type (Derived_Base)
17637 or else Is_Completely_Hidden
17638 (First_Stored_Discriminant (Derived_Base))
17639 or else Is_Generic_Type (Derived_Base))
17641 D := First_Discriminant (Derived_Base);
17642 while Present (D) loop
17643 Append_Elmt (New_Occurrence_Of (D, Loc), Discs);
17644 Next_Discriminant (D);
17648 -- Finally, inherit non-discriminant components unless they are not
17649 -- visible because defined or inherited from the full view of the
17650 -- parent. Don't inherit the _parent field of the parent type.
17652 Component := First_Entity (Parent_Base);
17653 while Present (Component) loop
17655 -- Ada 2005 (AI-251): Do not inherit components associated with
17656 -- secondary tags of the parent.
17658 if Ekind (Component) = E_Component
17659 and then Present (Related_Type (Component))
17663 elsif Ekind (Component) /= E_Component
17664 or else Chars (Component) = Name_uParent
17668 -- If the derived type is within the parent type's declarative
17669 -- region, then the components can still be inherited even though
17670 -- they aren't visible at this point. This can occur for cases
17671 -- such as within public child units where the components must
17672 -- become visible upon entering the child unit's private part.
17674 elsif not Is_Visible_Component (Component)
17675 and then not In_Open_Scopes (Scope (Parent_Base))
17679 elsif Ekind_In (Derived_Base, E_Private_Type,
17680 E_Limited_Private_Type)
17685 Inherit_Component (Component);
17688 Next_Entity (Component);
17691 -- For tagged derived types, inherited discriminants cannot be used in
17692 -- component declarations of the record extension part. To achieve this
17693 -- we mark the inherited discriminants as not visible.
17695 if Is_Tagged and then Inherit_Discr then
17696 D := First_Discriminant (Derived_Base);
17697 while Present (D) loop
17698 Set_Is_Immediately_Visible (D, False);
17699 Next_Discriminant (D);
17704 end Inherit_Components;
17706 -----------------------------
17707 -- Inherit_Predicate_Flags --
17708 -----------------------------
17710 procedure Inherit_Predicate_Flags (Subt, Par : Entity_Id) is
17712 Set_Has_Predicates (Subt, Has_Predicates (Par));
17713 Set_Has_Static_Predicate_Aspect
17714 (Subt, Has_Static_Predicate_Aspect (Par));
17715 Set_Has_Dynamic_Predicate_Aspect
17716 (Subt, Has_Dynamic_Predicate_Aspect (Par));
17717 end Inherit_Predicate_Flags;
17719 ----------------------
17720 -- Is_EVF_Procedure --
17721 ----------------------
17723 function Is_EVF_Procedure (Subp : Entity_Id) return Boolean is
17724 Formal : Entity_Id;
17727 -- Examine the formals of an Extensions_Visible False procedure looking
17728 -- for a controlling OUT parameter.
17730 if Ekind (Subp) = E_Procedure
17731 and then Extensions_Visible_Status (Subp) = Extensions_Visible_False
17733 Formal := First_Formal (Subp);
17734 while Present (Formal) loop
17735 if Ekind (Formal) = E_Out_Parameter
17736 and then Is_Controlling_Formal (Formal)
17741 Next_Formal (Formal);
17746 end Is_EVF_Procedure;
17748 -----------------------
17749 -- Is_Null_Extension --
17750 -----------------------
17752 function Is_Null_Extension (T : Entity_Id) return Boolean is
17753 Type_Decl : constant Node_Id := Parent (Base_Type (T));
17754 Comp_List : Node_Id;
17758 if Nkind (Type_Decl) /= N_Full_Type_Declaration
17759 or else not Is_Tagged_Type (T)
17760 or else Nkind (Type_Definition (Type_Decl)) /=
17761 N_Derived_Type_Definition
17762 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
17768 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
17770 if Present (Discriminant_Specifications (Type_Decl)) then
17773 elsif Present (Comp_List)
17774 and then Is_Non_Empty_List (Component_Items (Comp_List))
17776 Comp := First (Component_Items (Comp_List));
17778 -- Only user-defined components are relevant. The component list
17779 -- may also contain a parent component and internal components
17780 -- corresponding to secondary tags, but these do not determine
17781 -- whether this is a null extension.
17783 while Present (Comp) loop
17784 if Comes_From_Source (Comp) then
17796 end Is_Null_Extension;
17798 ------------------------------
17799 -- Is_Valid_Constraint_Kind --
17800 ------------------------------
17802 function Is_Valid_Constraint_Kind
17803 (T_Kind : Type_Kind;
17804 Constraint_Kind : Node_Kind) return Boolean
17808 when Enumeration_Kind |
17810 return Constraint_Kind = N_Range_Constraint;
17812 when Decimal_Fixed_Point_Kind =>
17813 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
17814 N_Range_Constraint);
17816 when Ordinary_Fixed_Point_Kind =>
17817 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
17818 N_Range_Constraint);
17821 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
17822 N_Range_Constraint);
17829 E_Incomplete_Type |
17832 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
17835 return True; -- Error will be detected later
17837 end Is_Valid_Constraint_Kind;
17839 --------------------------
17840 -- Is_Visible_Component --
17841 --------------------------
17843 function Is_Visible_Component
17845 N : Node_Id := Empty) return Boolean
17847 Original_Comp : Entity_Id := Empty;
17848 Original_Type : Entity_Id;
17849 Type_Scope : Entity_Id;
17851 function Is_Local_Type (Typ : Entity_Id) return Boolean;
17852 -- Check whether parent type of inherited component is declared locally,
17853 -- possibly within a nested package or instance. The current scope is
17854 -- the derived record itself.
17856 -------------------
17857 -- Is_Local_Type --
17858 -------------------
17860 function Is_Local_Type (Typ : Entity_Id) return Boolean is
17864 Scop := Scope (Typ);
17865 while Present (Scop)
17866 and then Scop /= Standard_Standard
17868 if Scop = Scope (Current_Scope) then
17872 Scop := Scope (Scop);
17878 -- Start of processing for Is_Visible_Component
17881 if Ekind_In (C, E_Component, E_Discriminant) then
17882 Original_Comp := Original_Record_Component (C);
17885 if No (Original_Comp) then
17887 -- Premature usage, or previous error
17892 Original_Type := Scope (Original_Comp);
17893 Type_Scope := Scope (Base_Type (Scope (C)));
17896 -- This test only concerns tagged types
17898 if not Is_Tagged_Type (Original_Type) then
17901 -- If it is _Parent or _Tag, there is no visibility issue
17903 elsif not Comes_From_Source (Original_Comp) then
17906 -- Discriminants are visible unless the (private) type has unknown
17907 -- discriminants. If the discriminant reference is inserted for a
17908 -- discriminant check on a full view it is also visible.
17910 elsif Ekind (Original_Comp) = E_Discriminant
17912 (not Has_Unknown_Discriminants (Original_Type)
17913 or else (Present (N)
17914 and then Nkind (N) = N_Selected_Component
17915 and then Nkind (Prefix (N)) = N_Type_Conversion
17916 and then not Comes_From_Source (Prefix (N))))
17920 -- In the body of an instantiation, no need to check for the visibility
17923 elsif In_Instance_Body then
17926 -- If the component has been declared in an ancestor which is currently
17927 -- a private type, then it is not visible. The same applies if the
17928 -- component's containing type is not in an open scope and the original
17929 -- component's enclosing type is a visible full view of a private type
17930 -- (which can occur in cases where an attempt is being made to reference
17931 -- a component in a sibling package that is inherited from a visible
17932 -- component of a type in an ancestor package; the component in the
17933 -- sibling package should not be visible even though the component it
17934 -- inherited from is visible). This does not apply however in the case
17935 -- where the scope of the type is a private child unit, or when the
17936 -- parent comes from a local package in which the ancestor is currently
17937 -- visible. The latter suppression of visibility is needed for cases
17938 -- that are tested in B730006.
17940 elsif Is_Private_Type (Original_Type)
17942 (not Is_Private_Descendant (Type_Scope)
17943 and then not In_Open_Scopes (Type_Scope)
17944 and then Has_Private_Declaration (Original_Type))
17946 -- If the type derives from an entity in a formal package, there
17947 -- are no additional visible components.
17949 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
17950 N_Formal_Package_Declaration
17954 -- if we are not in the private part of the current package, there
17955 -- are no additional visible components.
17957 elsif Ekind (Scope (Current_Scope)) = E_Package
17958 and then not In_Private_Part (Scope (Current_Scope))
17963 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
17964 and then In_Open_Scopes (Scope (Original_Type))
17965 and then Is_Local_Type (Type_Scope);
17968 -- There is another weird way in which a component may be invisible when
17969 -- the private and the full view are not derived from the same ancestor.
17970 -- Here is an example :
17972 -- type A1 is tagged record F1 : integer; end record;
17973 -- type A2 is new A1 with record F2 : integer; end record;
17974 -- type T is new A1 with private;
17976 -- type T is new A2 with null record;
17978 -- In this case, the full view of T inherits F1 and F2 but the private
17979 -- view inherits only F1
17983 Ancestor : Entity_Id := Scope (C);
17987 if Ancestor = Original_Type then
17990 -- The ancestor may have a partial view of the original type,
17991 -- but if the full view is in scope, as in a child body, the
17992 -- component is visible.
17994 elsif In_Private_Part (Scope (Original_Type))
17995 and then Full_View (Ancestor) = Original_Type
17999 elsif Ancestor = Etype (Ancestor) then
18001 -- No further ancestors to examine
18006 Ancestor := Etype (Ancestor);
18010 end Is_Visible_Component;
18012 --------------------------
18013 -- Make_Class_Wide_Type --
18014 --------------------------
18016 procedure Make_Class_Wide_Type (T : Entity_Id) is
18017 CW_Type : Entity_Id;
18019 Next_E : Entity_Id;
18022 if Present (Class_Wide_Type (T)) then
18024 -- The class-wide type is a partially decorated entity created for a
18025 -- unanalyzed tagged type referenced through a limited with clause.
18026 -- When the tagged type is analyzed, its class-wide type needs to be
18027 -- redecorated. Note that we reuse the entity created by Decorate_
18028 -- Tagged_Type in order to preserve all links.
18030 if Materialize_Entity (Class_Wide_Type (T)) then
18031 CW_Type := Class_Wide_Type (T);
18032 Set_Materialize_Entity (CW_Type, False);
18034 -- The class wide type can have been defined by the partial view, in
18035 -- which case everything is already done.
18041 -- Default case, we need to create a new class-wide type
18045 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
18048 -- Inherit root type characteristics
18050 CW_Name := Chars (CW_Type);
18051 Next_E := Next_Entity (CW_Type);
18052 Copy_Node (T, CW_Type);
18053 Set_Comes_From_Source (CW_Type, False);
18054 Set_Chars (CW_Type, CW_Name);
18055 Set_Parent (CW_Type, Parent (T));
18056 Set_Next_Entity (CW_Type, Next_E);
18058 -- Ensure we have a new freeze node for the class-wide type. The partial
18059 -- view may have freeze action of its own, requiring a proper freeze
18060 -- node, and the same freeze node cannot be shared between the two
18063 Set_Has_Delayed_Freeze (CW_Type);
18064 Set_Freeze_Node (CW_Type, Empty);
18066 -- Customize the class-wide type: It has no prim. op., it cannot be
18067 -- abstract and its Etype points back to the specific root type.
18069 Set_Ekind (CW_Type, E_Class_Wide_Type);
18070 Set_Is_Tagged_Type (CW_Type, True);
18071 Set_Direct_Primitive_Operations (CW_Type, New_Elmt_List);
18072 Set_Is_Abstract_Type (CW_Type, False);
18073 Set_Is_Constrained (CW_Type, False);
18074 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
18075 Set_Default_SSO (CW_Type);
18077 if Ekind (T) = E_Class_Wide_Subtype then
18078 Set_Etype (CW_Type, Etype (Base_Type (T)));
18080 Set_Etype (CW_Type, T);
18083 Set_No_Tagged_Streams_Pragma (CW_Type, No_Tagged_Streams);
18085 -- If this is the class_wide type of a constrained subtype, it does
18086 -- not have discriminants.
18088 Set_Has_Discriminants (CW_Type,
18089 Has_Discriminants (T) and then not Is_Constrained (T));
18091 Set_Has_Unknown_Discriminants (CW_Type, True);
18092 Set_Class_Wide_Type (T, CW_Type);
18093 Set_Equivalent_Type (CW_Type, Empty);
18095 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
18097 Set_Class_Wide_Type (CW_Type, CW_Type);
18099 -- Inherit the "ghostness" from the root tagged type
18101 if Ghost_Mode > None or else Is_Ghost_Entity (T) then
18102 Set_Is_Ghost_Entity (CW_Type);
18104 end Make_Class_Wide_Type;
18110 procedure Make_Index
18112 Related_Nod : Node_Id;
18113 Related_Id : Entity_Id := Empty;
18114 Suffix_Index : Nat := 1;
18115 In_Iter_Schm : Boolean := False)
18119 Def_Id : Entity_Id := Empty;
18120 Found : Boolean := False;
18123 -- For a discrete range used in a constrained array definition and
18124 -- defined by a range, an implicit conversion to the predefined type
18125 -- INTEGER is assumed if each bound is either a numeric literal, a named
18126 -- number, or an attribute, and the type of both bounds (prior to the
18127 -- implicit conversion) is the type universal_integer. Otherwise, both
18128 -- bounds must be of the same discrete type, other than universal
18129 -- integer; this type must be determinable independently of the
18130 -- context, but using the fact that the type must be discrete and that
18131 -- both bounds must have the same type.
18133 -- Character literals also have a universal type in the absence of
18134 -- of additional context, and are resolved to Standard_Character.
18136 if Nkind (N) = N_Range then
18138 -- The index is given by a range constraint. The bounds are known
18139 -- to be of a consistent type.
18141 if not Is_Overloaded (N) then
18144 -- For universal bounds, choose the specific predefined type
18146 if T = Universal_Integer then
18147 T := Standard_Integer;
18149 elsif T = Any_Character then
18150 Ambiguous_Character (Low_Bound (N));
18152 T := Standard_Character;
18155 -- The node may be overloaded because some user-defined operators
18156 -- are available, but if a universal interpretation exists it is
18157 -- also the selected one.
18159 elsif Universal_Interpretation (N) = Universal_Integer then
18160 T := Standard_Integer;
18166 Ind : Interp_Index;
18170 Get_First_Interp (N, Ind, It);
18171 while Present (It.Typ) loop
18172 if Is_Discrete_Type (It.Typ) then
18175 and then not Covers (It.Typ, T)
18176 and then not Covers (T, It.Typ)
18178 Error_Msg_N ("ambiguous bounds in discrete range", N);
18186 Get_Next_Interp (Ind, It);
18189 if T = Any_Type then
18190 Error_Msg_N ("discrete type required for range", N);
18191 Set_Etype (N, Any_Type);
18194 elsif T = Universal_Integer then
18195 T := Standard_Integer;
18200 if not Is_Discrete_Type (T) then
18201 Error_Msg_N ("discrete type required for range", N);
18202 Set_Etype (N, Any_Type);
18206 if Nkind (Low_Bound (N)) = N_Attribute_Reference
18207 and then Attribute_Name (Low_Bound (N)) = Name_First
18208 and then Is_Entity_Name (Prefix (Low_Bound (N)))
18209 and then Is_Type (Entity (Prefix (Low_Bound (N))))
18210 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (N))))
18212 -- The type of the index will be the type of the prefix, as long
18213 -- as the upper bound is 'Last of the same type.
18215 Def_Id := Entity (Prefix (Low_Bound (N)));
18217 if Nkind (High_Bound (N)) /= N_Attribute_Reference
18218 or else Attribute_Name (High_Bound (N)) /= Name_Last
18219 or else not Is_Entity_Name (Prefix (High_Bound (N)))
18220 or else Entity (Prefix (High_Bound (N))) /= Def_Id
18227 Process_Range_Expr_In_Decl (R, T, In_Iter_Schm => In_Iter_Schm);
18229 elsif Nkind (N) = N_Subtype_Indication then
18231 -- The index is given by a subtype with a range constraint
18233 T := Base_Type (Entity (Subtype_Mark (N)));
18235 if not Is_Discrete_Type (T) then
18236 Error_Msg_N ("discrete type required for range", N);
18237 Set_Etype (N, Any_Type);
18241 R := Range_Expression (Constraint (N));
18244 Process_Range_Expr_In_Decl
18245 (R, Entity (Subtype_Mark (N)), In_Iter_Schm => In_Iter_Schm);
18247 elsif Nkind (N) = N_Attribute_Reference then
18249 -- Catch beginner's error (use of attribute other than 'Range)
18251 if Attribute_Name (N) /= Name_Range then
18252 Error_Msg_N ("expect attribute ''Range", N);
18253 Set_Etype (N, Any_Type);
18257 -- If the node denotes the range of a type mark, that is also the
18258 -- resulting type, and we do not need to create an Itype for it.
18260 if Is_Entity_Name (Prefix (N))
18261 and then Comes_From_Source (N)
18262 and then Is_Type (Entity (Prefix (N)))
18263 and then Is_Discrete_Type (Entity (Prefix (N)))
18265 Def_Id := Entity (Prefix (N));
18268 Analyze_And_Resolve (N);
18272 -- If none of the above, must be a subtype. We convert this to a
18273 -- range attribute reference because in the case of declared first
18274 -- named subtypes, the types in the range reference can be different
18275 -- from the type of the entity. A range attribute normalizes the
18276 -- reference and obtains the correct types for the bounds.
18278 -- This transformation is in the nature of an expansion, is only
18279 -- done if expansion is active. In particular, it is not done on
18280 -- formal generic types, because we need to retain the name of the
18281 -- original index for instantiation purposes.
18284 if not Is_Entity_Name (N) or else not Is_Type (Entity (N)) then
18285 Error_Msg_N ("invalid subtype mark in discrete range ", N);
18286 Set_Etype (N, Any_Integer);
18290 -- The type mark may be that of an incomplete type. It is only
18291 -- now that we can get the full view, previous analysis does
18292 -- not look specifically for a type mark.
18294 Set_Entity (N, Get_Full_View (Entity (N)));
18295 Set_Etype (N, Entity (N));
18296 Def_Id := Entity (N);
18298 if not Is_Discrete_Type (Def_Id) then
18299 Error_Msg_N ("discrete type required for index", N);
18300 Set_Etype (N, Any_Type);
18305 if Expander_Active then
18307 Make_Attribute_Reference (Sloc (N),
18308 Attribute_Name => Name_Range,
18309 Prefix => Relocate_Node (N)));
18311 -- The original was a subtype mark that does not freeze. This
18312 -- means that the rewritten version must not freeze either.
18314 Set_Must_Not_Freeze (N);
18315 Set_Must_Not_Freeze (Prefix (N));
18316 Analyze_And_Resolve (N);
18320 -- If expander is inactive, type is legal, nothing else to construct
18327 if not Is_Discrete_Type (T) then
18328 Error_Msg_N ("discrete type required for range", N);
18329 Set_Etype (N, Any_Type);
18332 elsif T = Any_Type then
18333 Set_Etype (N, Any_Type);
18337 -- We will now create the appropriate Itype to describe the range, but
18338 -- first a check. If we originally had a subtype, then we just label
18339 -- the range with this subtype. Not only is there no need to construct
18340 -- a new subtype, but it is wrong to do so for two reasons:
18342 -- 1. A legality concern, if we have a subtype, it must not freeze,
18343 -- and the Itype would cause freezing incorrectly
18345 -- 2. An efficiency concern, if we created an Itype, it would not be
18346 -- recognized as the same type for the purposes of eliminating
18347 -- checks in some circumstances.
18349 -- We signal this case by setting the subtype entity in Def_Id
18351 if No (Def_Id) then
18353 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
18354 Set_Etype (Def_Id, Base_Type (T));
18356 if Is_Signed_Integer_Type (T) then
18357 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
18359 elsif Is_Modular_Integer_Type (T) then
18360 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
18363 Set_Ekind (Def_Id, E_Enumeration_Subtype);
18364 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
18365 Set_First_Literal (Def_Id, First_Literal (T));
18368 Set_Size_Info (Def_Id, (T));
18369 Set_RM_Size (Def_Id, RM_Size (T));
18370 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
18372 Set_Scalar_Range (Def_Id, R);
18373 Conditional_Delay (Def_Id, T);
18375 if Nkind (N) = N_Subtype_Indication then
18376 Inherit_Predicate_Flags (Def_Id, Entity (Subtype_Mark (N)));
18379 -- In the subtype indication case, if the immediate parent of the
18380 -- new subtype is non-static, then the subtype we create is non-
18381 -- static, even if its bounds are static.
18383 if Nkind (N) = N_Subtype_Indication
18384 and then not Is_OK_Static_Subtype (Entity (Subtype_Mark (N)))
18386 Set_Is_Non_Static_Subtype (Def_Id);
18390 -- Final step is to label the index with this constructed type
18392 Set_Etype (N, Def_Id);
18395 ------------------------------
18396 -- Modular_Type_Declaration --
18397 ------------------------------
18399 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
18400 Mod_Expr : constant Node_Id := Expression (Def);
18403 procedure Set_Modular_Size (Bits : Int);
18404 -- Sets RM_Size to Bits, and Esize to normal word size above this
18406 ----------------------
18407 -- Set_Modular_Size --
18408 ----------------------
18410 procedure Set_Modular_Size (Bits : Int) is
18412 Set_RM_Size (T, UI_From_Int (Bits));
18417 elsif Bits <= 16 then
18418 Init_Esize (T, 16);
18420 elsif Bits <= 32 then
18421 Init_Esize (T, 32);
18424 Init_Esize (T, System_Max_Binary_Modulus_Power);
18427 if not Non_Binary_Modulus (T) and then Esize (T) = RM_Size (T) then
18428 Set_Is_Known_Valid (T);
18430 end Set_Modular_Size;
18432 -- Start of processing for Modular_Type_Declaration
18435 -- If the mod expression is (exactly) 2 * literal, where literal is
18436 -- 64 or less,then almost certainly the * was meant to be **. Warn.
18438 if Warn_On_Suspicious_Modulus_Value
18439 and then Nkind (Mod_Expr) = N_Op_Multiply
18440 and then Nkind (Left_Opnd (Mod_Expr)) = N_Integer_Literal
18441 and then Intval (Left_Opnd (Mod_Expr)) = Uint_2
18442 and then Nkind (Right_Opnd (Mod_Expr)) = N_Integer_Literal
18443 and then Intval (Right_Opnd (Mod_Expr)) <= Uint_64
18446 ("suspicious MOD value, was '*'* intended'??M?", Mod_Expr);
18449 -- Proceed with analysis of mod expression
18451 Analyze_And_Resolve (Mod_Expr, Any_Integer);
18453 Set_Ekind (T, E_Modular_Integer_Type);
18454 Init_Alignment (T);
18455 Set_Is_Constrained (T);
18457 if not Is_OK_Static_Expression (Mod_Expr) then
18458 Flag_Non_Static_Expr
18459 ("non-static expression used for modular type bound!", Mod_Expr);
18460 M_Val := 2 ** System_Max_Binary_Modulus_Power;
18462 M_Val := Expr_Value (Mod_Expr);
18466 Error_Msg_N ("modulus value must be positive", Mod_Expr);
18467 M_Val := 2 ** System_Max_Binary_Modulus_Power;
18470 if M_Val > 2 ** Standard_Long_Integer_Size then
18471 Check_Restriction (No_Long_Long_Integers, Mod_Expr);
18474 Set_Modulus (T, M_Val);
18476 -- Create bounds for the modular type based on the modulus given in
18477 -- the type declaration and then analyze and resolve those bounds.
18479 Set_Scalar_Range (T,
18480 Make_Range (Sloc (Mod_Expr),
18481 Low_Bound => Make_Integer_Literal (Sloc (Mod_Expr), 0),
18482 High_Bound => Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
18484 -- Properly analyze the literals for the range. We do this manually
18485 -- because we can't go calling Resolve, since we are resolving these
18486 -- bounds with the type, and this type is certainly not complete yet.
18488 Set_Etype (Low_Bound (Scalar_Range (T)), T);
18489 Set_Etype (High_Bound (Scalar_Range (T)), T);
18490 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
18491 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
18493 -- Loop through powers of two to find number of bits required
18495 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
18499 if M_Val = 2 ** Bits then
18500 Set_Modular_Size (Bits);
18505 elsif M_Val < 2 ** Bits then
18506 Check_SPARK_05_Restriction ("modulus should be a power of 2", T);
18507 Set_Non_Binary_Modulus (T);
18509 if Bits > System_Max_Nonbinary_Modulus_Power then
18510 Error_Msg_Uint_1 :=
18511 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
18513 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
18514 Set_Modular_Size (System_Max_Binary_Modulus_Power);
18518 -- In the nonbinary case, set size as per RM 13.3(55)
18520 Set_Modular_Size (Bits);
18527 -- If we fall through, then the size exceed System.Max_Binary_Modulus
18528 -- so we just signal an error and set the maximum size.
18530 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
18531 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
18533 Set_Modular_Size (System_Max_Binary_Modulus_Power);
18534 Init_Alignment (T);
18536 end Modular_Type_Declaration;
18538 --------------------------
18539 -- New_Concatenation_Op --
18540 --------------------------
18542 procedure New_Concatenation_Op (Typ : Entity_Id) is
18543 Loc : constant Source_Ptr := Sloc (Typ);
18546 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
18547 -- Create abbreviated declaration for the formal of a predefined
18548 -- Operator 'Op' of type 'Typ'
18550 --------------------
18551 -- Make_Op_Formal --
18552 --------------------
18554 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
18555 Formal : Entity_Id;
18557 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
18558 Set_Etype (Formal, Typ);
18559 Set_Mechanism (Formal, Default_Mechanism);
18561 end Make_Op_Formal;
18563 -- Start of processing for New_Concatenation_Op
18566 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
18568 Set_Ekind (Op, E_Operator);
18569 Set_Scope (Op, Current_Scope);
18570 Set_Etype (Op, Typ);
18571 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
18572 Set_Is_Immediately_Visible (Op);
18573 Set_Is_Intrinsic_Subprogram (Op);
18574 Set_Has_Completion (Op);
18575 Append_Entity (Op, Current_Scope);
18577 Set_Name_Entity_Id (Name_Op_Concat, Op);
18579 Append_Entity (Make_Op_Formal (Typ, Op), Op);
18580 Append_Entity (Make_Op_Formal (Typ, Op), Op);
18581 end New_Concatenation_Op;
18583 -------------------------
18584 -- OK_For_Limited_Init --
18585 -------------------------
18587 -- ???Check all calls of this, and compare the conditions under which it's
18590 function OK_For_Limited_Init
18592 Exp : Node_Id) return Boolean
18595 return Is_CPP_Constructor_Call (Exp)
18596 or else (Ada_Version >= Ada_2005
18597 and then not Debug_Flag_Dot_L
18598 and then OK_For_Limited_Init_In_05 (Typ, Exp));
18599 end OK_For_Limited_Init;
18601 -------------------------------
18602 -- OK_For_Limited_Init_In_05 --
18603 -------------------------------
18605 function OK_For_Limited_Init_In_05
18607 Exp : Node_Id) return Boolean
18610 -- An object of a limited interface type can be initialized with any
18611 -- expression of a nonlimited descendant type.
18613 if Is_Class_Wide_Type (Typ)
18614 and then Is_Limited_Interface (Typ)
18615 and then not Is_Limited_Type (Etype (Exp))
18620 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
18621 -- case of limited aggregates (including extension aggregates), and
18622 -- function calls. The function call may have been given in prefixed
18623 -- notation, in which case the original node is an indexed component.
18624 -- If the function is parameterless, the original node was an explicit
18625 -- dereference. The function may also be parameterless, in which case
18626 -- the source node is just an identifier.
18628 case Nkind (Original_Node (Exp)) is
18629 when N_Aggregate | N_Extension_Aggregate | N_Function_Call | N_Op =>
18632 when N_Identifier =>
18633 return Present (Entity (Original_Node (Exp)))
18634 and then Ekind (Entity (Original_Node (Exp))) = E_Function;
18636 when N_Qualified_Expression =>
18638 OK_For_Limited_Init_In_05
18639 (Typ, Expression (Original_Node (Exp)));
18641 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
18642 -- with a function call, the expander has rewritten the call into an
18643 -- N_Type_Conversion node to force displacement of the pointer to
18644 -- reference the component containing the secondary dispatch table.
18645 -- Otherwise a type conversion is not a legal context.
18646 -- A return statement for a build-in-place function returning a
18647 -- synchronized type also introduces an unchecked conversion.
18649 when N_Type_Conversion |
18650 N_Unchecked_Type_Conversion =>
18651 return not Comes_From_Source (Exp)
18653 OK_For_Limited_Init_In_05
18654 (Typ, Expression (Original_Node (Exp)));
18656 when N_Indexed_Component |
18657 N_Selected_Component |
18658 N_Explicit_Dereference =>
18659 return Nkind (Exp) = N_Function_Call;
18661 -- A use of 'Input is a function call, hence allowed. Normally the
18662 -- attribute will be changed to a call, but the attribute by itself
18663 -- can occur with -gnatc.
18665 when N_Attribute_Reference =>
18666 return Attribute_Name (Original_Node (Exp)) = Name_Input;
18668 -- For a case expression, all dependent expressions must be legal
18670 when N_Case_Expression =>
18675 Alt := First (Alternatives (Original_Node (Exp)));
18676 while Present (Alt) loop
18677 if not OK_For_Limited_Init_In_05 (Typ, Expression (Alt)) then
18687 -- For an if expression, all dependent expressions must be legal
18689 when N_If_Expression =>
18691 Then_Expr : constant Node_Id :=
18692 Next (First (Expressions (Original_Node (Exp))));
18693 Else_Expr : constant Node_Id := Next (Then_Expr);
18695 return OK_For_Limited_Init_In_05 (Typ, Then_Expr)
18697 OK_For_Limited_Init_In_05 (Typ, Else_Expr);
18703 end OK_For_Limited_Init_In_05;
18705 -------------------------------------------
18706 -- Ordinary_Fixed_Point_Type_Declaration --
18707 -------------------------------------------
18709 procedure Ordinary_Fixed_Point_Type_Declaration
18713 Loc : constant Source_Ptr := Sloc (Def);
18714 Delta_Expr : constant Node_Id := Delta_Expression (Def);
18715 RRS : constant Node_Id := Real_Range_Specification (Def);
18716 Implicit_Base : Entity_Id;
18723 Check_Restriction (No_Fixed_Point, Def);
18725 -- Create implicit base type
18728 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
18729 Set_Etype (Implicit_Base, Implicit_Base);
18731 -- Analyze and process delta expression
18733 Analyze_And_Resolve (Delta_Expr, Any_Real);
18735 Check_Delta_Expression (Delta_Expr);
18736 Delta_Val := Expr_Value_R (Delta_Expr);
18738 Set_Delta_Value (Implicit_Base, Delta_Val);
18740 -- Compute default small from given delta, which is the largest power
18741 -- of two that does not exceed the given delta value.
18751 if Delta_Val < Ureal_1 then
18752 while Delta_Val < Tmp loop
18753 Tmp := Tmp / Ureal_2;
18754 Scale := Scale + 1;
18759 Tmp := Tmp * Ureal_2;
18760 exit when Tmp > Delta_Val;
18761 Scale := Scale - 1;
18765 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
18768 Set_Small_Value (Implicit_Base, Small_Val);
18770 -- If no range was given, set a dummy range
18772 if RRS <= Empty_Or_Error then
18773 Low_Val := -Small_Val;
18774 High_Val := Small_Val;
18776 -- Otherwise analyze and process given range
18780 Low : constant Node_Id := Low_Bound (RRS);
18781 High : constant Node_Id := High_Bound (RRS);
18784 Analyze_And_Resolve (Low, Any_Real);
18785 Analyze_And_Resolve (High, Any_Real);
18786 Check_Real_Bound (Low);
18787 Check_Real_Bound (High);
18789 -- Obtain and set the range
18791 Low_Val := Expr_Value_R (Low);
18792 High_Val := Expr_Value_R (High);
18794 if Low_Val > High_Val then
18795 Error_Msg_NE ("??fixed point type& has null range", Def, T);
18800 -- The range for both the implicit base and the declared first subtype
18801 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
18802 -- set a temporary range in place. Note that the bounds of the base
18803 -- type will be widened to be symmetrical and to fill the available
18804 -- bits when the type is frozen.
18806 -- We could do this with all discrete types, and probably should, but
18807 -- we absolutely have to do it for fixed-point, since the end-points
18808 -- of the range and the size are determined by the small value, which
18809 -- could be reset before the freeze point.
18811 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
18812 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
18814 -- Complete definition of first subtype. The inheritance of the rep item
18815 -- chain ensures that SPARK-related pragmas are not clobbered when the
18816 -- ordinary fixed point type acts as a full view of a private type.
18818 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
18819 Set_Etype (T, Implicit_Base);
18820 Init_Size_Align (T);
18821 Inherit_Rep_Item_Chain (T, Implicit_Base);
18822 Set_Small_Value (T, Small_Val);
18823 Set_Delta_Value (T, Delta_Val);
18824 Set_Is_Constrained (T);
18825 end Ordinary_Fixed_Point_Type_Declaration;
18827 ----------------------------------
18828 -- Preanalyze_Assert_Expression --
18829 ----------------------------------
18831 procedure Preanalyze_Assert_Expression (N : Node_Id; T : Entity_Id) is
18833 In_Assertion_Expr := In_Assertion_Expr + 1;
18834 Preanalyze_Spec_Expression (N, T);
18835 In_Assertion_Expr := In_Assertion_Expr - 1;
18836 end Preanalyze_Assert_Expression;
18838 -----------------------------------
18839 -- Preanalyze_Default_Expression --
18840 -----------------------------------
18842 procedure Preanalyze_Default_Expression (N : Node_Id; T : Entity_Id) is
18843 Save_In_Default_Expr : constant Boolean := In_Default_Expr;
18845 In_Default_Expr := True;
18846 Preanalyze_Spec_Expression (N, T);
18847 In_Default_Expr := Save_In_Default_Expr;
18848 end Preanalyze_Default_Expression;
18850 --------------------------------
18851 -- Preanalyze_Spec_Expression --
18852 --------------------------------
18854 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
18855 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
18857 In_Spec_Expression := True;
18858 Preanalyze_And_Resolve (N, T);
18859 In_Spec_Expression := Save_In_Spec_Expression;
18860 end Preanalyze_Spec_Expression;
18862 ----------------------------------------
18863 -- Prepare_Private_Subtype_Completion --
18864 ----------------------------------------
18866 procedure Prepare_Private_Subtype_Completion
18868 Related_Nod : Node_Id)
18870 Id_B : constant Entity_Id := Base_Type (Id);
18871 Full_B : Entity_Id := Full_View (Id_B);
18875 if Present (Full_B) then
18877 -- Get to the underlying full view if necessary
18879 if Is_Private_Type (Full_B)
18880 and then Present (Underlying_Full_View (Full_B))
18882 Full_B := Underlying_Full_View (Full_B);
18885 -- The Base_Type is already completed, we can complete the subtype
18886 -- now. We have to create a new entity with the same name, Thus we
18887 -- can't use Create_Itype.
18889 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
18890 Set_Is_Itype (Full);
18891 Set_Associated_Node_For_Itype (Full, Related_Nod);
18892 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
18895 -- The parent subtype may be private, but the base might not, in some
18896 -- nested instances. In that case, the subtype does not need to be
18897 -- exchanged. It would still be nice to make private subtypes and their
18898 -- bases consistent at all times ???
18900 if Is_Private_Type (Id_B) then
18901 Append_Elmt (Id, Private_Dependents (Id_B));
18903 end Prepare_Private_Subtype_Completion;
18905 ---------------------------
18906 -- Process_Discriminants --
18907 ---------------------------
18909 procedure Process_Discriminants
18911 Prev : Entity_Id := Empty)
18913 Elist : constant Elist_Id := New_Elmt_List;
18916 Discr_Number : Uint;
18917 Discr_Type : Entity_Id;
18918 Default_Present : Boolean := False;
18919 Default_Not_Present : Boolean := False;
18922 -- A composite type other than an array type can have discriminants.
18923 -- On entry, the current scope is the composite type.
18925 -- The discriminants are initially entered into the scope of the type
18926 -- via Enter_Name with the default Ekind of E_Void to prevent premature
18927 -- use, as explained at the end of this procedure.
18929 Discr := First (Discriminant_Specifications (N));
18930 while Present (Discr) loop
18931 Enter_Name (Defining_Identifier (Discr));
18933 -- For navigation purposes we add a reference to the discriminant
18934 -- in the entity for the type. If the current declaration is a
18935 -- completion, place references on the partial view. Otherwise the
18936 -- type is the current scope.
18938 if Present (Prev) then
18940 -- The references go on the partial view, if present. If the
18941 -- partial view has discriminants, the references have been
18942 -- generated already.
18944 if not Has_Discriminants (Prev) then
18945 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
18949 (Current_Scope, Defining_Identifier (Discr), 'd');
18952 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
18953 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
18955 -- Ada 2005 (AI-254)
18957 if Present (Access_To_Subprogram_Definition
18958 (Discriminant_Type (Discr)))
18959 and then Protected_Present (Access_To_Subprogram_Definition
18960 (Discriminant_Type (Discr)))
18963 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
18967 Find_Type (Discriminant_Type (Discr));
18968 Discr_Type := Etype (Discriminant_Type (Discr));
18970 if Error_Posted (Discriminant_Type (Discr)) then
18971 Discr_Type := Any_Type;
18975 -- Handling of discriminants that are access types
18977 if Is_Access_Type (Discr_Type) then
18979 -- Ada 2005 (AI-230): Access discriminant allowed in non-
18980 -- limited record types
18982 if Ada_Version < Ada_2005 then
18983 Check_Access_Discriminant_Requires_Limited
18984 (Discr, Discriminant_Type (Discr));
18987 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
18989 ("(Ada 83) access discriminant not allowed", Discr);
18992 -- If not access type, must be a discrete type
18994 elsif not Is_Discrete_Type (Discr_Type) then
18996 ("discriminants must have a discrete or access type",
18997 Discriminant_Type (Discr));
19000 Set_Etype (Defining_Identifier (Discr), Discr_Type);
19002 -- If a discriminant specification includes the assignment compound
19003 -- delimiter followed by an expression, the expression is the default
19004 -- expression of the discriminant; the default expression must be of
19005 -- the type of the discriminant. (RM 3.7.1) Since this expression is
19006 -- a default expression, we do the special preanalysis, since this
19007 -- expression does not freeze (see section "Handling of Default and
19008 -- Per-Object Expressions" in spec of package Sem).
19010 if Present (Expression (Discr)) then
19011 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
19015 if Nkind (N) = N_Formal_Type_Declaration then
19017 ("discriminant defaults not allowed for formal type",
19018 Expression (Discr));
19020 -- Flag an error for a tagged type with defaulted discriminants,
19021 -- excluding limited tagged types when compiling for Ada 2012
19022 -- (see AI05-0214).
19024 elsif Is_Tagged_Type (Current_Scope)
19025 and then (not Is_Limited_Type (Current_Scope)
19026 or else Ada_Version < Ada_2012)
19027 and then Comes_From_Source (N)
19029 -- Note: see similar test in Check_Or_Process_Discriminants, to
19030 -- handle the (illegal) case of the completion of an untagged
19031 -- view with discriminants with defaults by a tagged full view.
19032 -- We skip the check if Discr does not come from source, to
19033 -- account for the case of an untagged derived type providing
19034 -- defaults for a renamed discriminant from a private untagged
19035 -- ancestor with a tagged full view (ACATS B460006).
19037 if Ada_Version >= Ada_2012 then
19039 ("discriminants of nonlimited tagged type cannot have"
19041 Expression (Discr));
19044 ("discriminants of tagged type cannot have defaults",
19045 Expression (Discr));
19049 Default_Present := True;
19050 Append_Elmt (Expression (Discr), Elist);
19052 -- Tag the defining identifiers for the discriminants with
19053 -- their corresponding default expressions from the tree.
19055 Set_Discriminant_Default_Value
19056 (Defining_Identifier (Discr), Expression (Discr));
19059 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag
19060 -- gets set unless we can be sure that no range check is required.
19062 if (GNATprove_Mode or not Expander_Active)
19065 (Expression (Discr), Discr_Type, Assume_Valid => True)
19067 Set_Do_Range_Check (Expression (Discr));
19070 -- No default discriminant value given
19073 Default_Not_Present := True;
19076 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
19077 -- Discr_Type but with the null-exclusion attribute
19079 if Ada_Version >= Ada_2005 then
19081 -- Ada 2005 (AI-231): Static checks
19083 if Can_Never_Be_Null (Discr_Type) then
19084 Null_Exclusion_Static_Checks (Discr);
19086 elsif Is_Access_Type (Discr_Type)
19087 and then Null_Exclusion_Present (Discr)
19089 -- No need to check itypes because in their case this check
19090 -- was done at their point of creation
19092 and then not Is_Itype (Discr_Type)
19094 if Can_Never_Be_Null (Discr_Type) then
19096 ("`NOT NULL` not allowed (& already excludes null)",
19101 Set_Etype (Defining_Identifier (Discr),
19102 Create_Null_Excluding_Itype
19104 Related_Nod => Discr));
19106 -- Check for improper null exclusion if the type is otherwise
19107 -- legal for a discriminant.
19109 elsif Null_Exclusion_Present (Discr)
19110 and then Is_Discrete_Type (Discr_Type)
19113 ("null exclusion can only apply to an access type", Discr);
19116 -- Ada 2005 (AI-402): access discriminants of nonlimited types
19117 -- can't have defaults. Synchronized types, or types that are
19118 -- explicitly limited are fine, but special tests apply to derived
19119 -- types in generics: in a generic body we have to assume the
19120 -- worst, and therefore defaults are not allowed if the parent is
19121 -- a generic formal private type (see ACATS B370001).
19123 if Is_Access_Type (Discr_Type) and then Default_Present then
19124 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
19125 or else Is_Limited_Record (Current_Scope)
19126 or else Is_Concurrent_Type (Current_Scope)
19127 or else Is_Concurrent_Record_Type (Current_Scope)
19128 or else Ekind (Current_Scope) = E_Limited_Private_Type
19130 if not Is_Derived_Type (Current_Scope)
19131 or else not Is_Generic_Type (Etype (Current_Scope))
19132 or else not In_Package_Body (Scope (Etype (Current_Scope)))
19133 or else Limited_Present
19134 (Type_Definition (Parent (Current_Scope)))
19140 ("access discriminants of nonlimited types cannot "
19141 & "have defaults", Expression (Discr));
19144 elsif Present (Expression (Discr)) then
19146 ("(Ada 2005) access discriminants of nonlimited types "
19147 & "cannot have defaults", Expression (Discr));
19152 -- A discriminant cannot be effectively volatile (SPARK RM 7.1.3(6)).
19153 -- This check is relevant only when SPARK_Mode is on as it is not a
19154 -- standard Ada legality rule.
19157 and then Is_Effectively_Volatile (Defining_Identifier (Discr))
19159 Error_Msg_N ("discriminant cannot be volatile", Discr);
19165 -- An element list consisting of the default expressions of the
19166 -- discriminants is constructed in the above loop and used to set
19167 -- the Discriminant_Constraint attribute for the type. If an object
19168 -- is declared of this (record or task) type without any explicit
19169 -- discriminant constraint given, this element list will form the
19170 -- actual parameters for the corresponding initialization procedure
19173 Set_Discriminant_Constraint (Current_Scope, Elist);
19174 Set_Stored_Constraint (Current_Scope, No_Elist);
19176 -- Default expressions must be provided either for all or for none
19177 -- of the discriminants of a discriminant part. (RM 3.7.1)
19179 if Default_Present and then Default_Not_Present then
19181 ("incomplete specification of defaults for discriminants", N);
19184 -- The use of the name of a discriminant is not allowed in default
19185 -- expressions of a discriminant part if the specification of the
19186 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
19188 -- To detect this, the discriminant names are entered initially with an
19189 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
19190 -- attempt to use a void entity (for example in an expression that is
19191 -- type-checked) produces the error message: premature usage. Now after
19192 -- completing the semantic analysis of the discriminant part, we can set
19193 -- the Ekind of all the discriminants appropriately.
19195 Discr := First (Discriminant_Specifications (N));
19196 Discr_Number := Uint_1;
19197 while Present (Discr) loop
19198 Id := Defining_Identifier (Discr);
19199 Set_Ekind (Id, E_Discriminant);
19200 Init_Component_Location (Id);
19202 Set_Discriminant_Number (Id, Discr_Number);
19204 -- Make sure this is always set, even in illegal programs
19206 Set_Corresponding_Discriminant (Id, Empty);
19208 -- Initialize the Original_Record_Component to the entity itself.
19209 -- Inherit_Components will propagate the right value to
19210 -- discriminants in derived record types.
19212 Set_Original_Record_Component (Id, Id);
19214 -- Create the discriminal for the discriminant
19216 Build_Discriminal (Id);
19219 Discr_Number := Discr_Number + 1;
19222 Set_Has_Discriminants (Current_Scope);
19223 end Process_Discriminants;
19225 -----------------------
19226 -- Process_Full_View --
19227 -----------------------
19229 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
19230 procedure Collect_Implemented_Interfaces
19232 Ifaces : Elist_Id);
19233 -- Ada 2005: Gather all the interfaces that Typ directly or
19234 -- inherently implements. Duplicate entries are not added to
19235 -- the list Ifaces.
19237 ------------------------------------
19238 -- Collect_Implemented_Interfaces --
19239 ------------------------------------
19241 procedure Collect_Implemented_Interfaces
19246 Iface_Elmt : Elmt_Id;
19249 -- Abstract interfaces are only associated with tagged record types
19251 if not Is_Tagged_Type (Typ) or else not Is_Record_Type (Typ) then
19255 -- Recursively climb to the ancestors
19257 if Etype (Typ) /= Typ
19259 -- Protect the frontend against wrong cyclic declarations like:
19261 -- type B is new A with private;
19262 -- type C is new A with private;
19264 -- type B is new C with null record;
19265 -- type C is new B with null record;
19267 and then Etype (Typ) /= Priv_T
19268 and then Etype (Typ) /= Full_T
19270 -- Keep separate the management of private type declarations
19272 if Ekind (Typ) = E_Record_Type_With_Private then
19274 -- Handle the following illegal usage:
19275 -- type Private_Type is tagged private;
19277 -- type Private_Type is new Type_Implementing_Iface;
19279 if Present (Full_View (Typ))
19280 and then Etype (Typ) /= Full_View (Typ)
19282 if Is_Interface (Etype (Typ)) then
19283 Append_Unique_Elmt (Etype (Typ), Ifaces);
19286 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
19289 -- Non-private types
19292 if Is_Interface (Etype (Typ)) then
19293 Append_Unique_Elmt (Etype (Typ), Ifaces);
19296 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
19300 -- Handle entities in the list of abstract interfaces
19302 if Present (Interfaces (Typ)) then
19303 Iface_Elmt := First_Elmt (Interfaces (Typ));
19304 while Present (Iface_Elmt) loop
19305 Iface := Node (Iface_Elmt);
19307 pragma Assert (Is_Interface (Iface));
19309 if not Contain_Interface (Iface, Ifaces) then
19310 Append_Elmt (Iface, Ifaces);
19311 Collect_Implemented_Interfaces (Iface, Ifaces);
19314 Next_Elmt (Iface_Elmt);
19317 end Collect_Implemented_Interfaces;
19321 Full_Indic : Node_Id;
19322 Full_Parent : Entity_Id;
19323 Priv_Parent : Entity_Id;
19325 -- Start of processing for Process_Full_View
19328 -- First some sanity checks that must be done after semantic
19329 -- decoration of the full view and thus cannot be placed with other
19330 -- similar checks in Find_Type_Name
19332 if not Is_Limited_Type (Priv_T)
19333 and then (Is_Limited_Type (Full_T)
19334 or else Is_Limited_Composite (Full_T))
19336 if In_Instance then
19340 ("completion of nonlimited type cannot be limited", Full_T);
19341 Explain_Limited_Type (Full_T, Full_T);
19344 elsif Is_Abstract_Type (Full_T)
19345 and then not Is_Abstract_Type (Priv_T)
19348 ("completion of nonabstract type cannot be abstract", Full_T);
19350 elsif Is_Tagged_Type (Priv_T)
19351 and then Is_Limited_Type (Priv_T)
19352 and then not Is_Limited_Type (Full_T)
19354 -- If pragma CPP_Class was applied to the private declaration
19355 -- propagate the limitedness to the full-view
19357 if Is_CPP_Class (Priv_T) then
19358 Set_Is_Limited_Record (Full_T);
19360 -- GNAT allow its own definition of Limited_Controlled to disobey
19361 -- this rule in order in ease the implementation. This test is safe
19362 -- because Root_Controlled is defined in a child of System that
19363 -- normal programs are not supposed to use.
19365 elsif Is_RTE (Etype (Full_T), RE_Root_Controlled) then
19366 Set_Is_Limited_Composite (Full_T);
19369 ("completion of limited tagged type must be limited", Full_T);
19372 elsif Is_Generic_Type (Priv_T) then
19373 Error_Msg_N ("generic type cannot have a completion", Full_T);
19376 -- Check that ancestor interfaces of private and full views are
19377 -- consistent. We omit this check for synchronized types because
19378 -- they are performed on the corresponding record type when frozen.
19380 if Ada_Version >= Ada_2005
19381 and then Is_Tagged_Type (Priv_T)
19382 and then Is_Tagged_Type (Full_T)
19383 and then not Is_Concurrent_Type (Full_T)
19387 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
19388 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
19391 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
19392 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
19394 -- Ada 2005 (AI-251): The partial view shall be a descendant of
19395 -- an interface type if and only if the full type is descendant
19396 -- of the interface type (AARM 7.3 (7.3/2)).
19398 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
19400 if Present (Iface) then
19402 ("interface in partial view& not implemented by full type "
19403 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
19406 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
19408 if Present (Iface) then
19410 ("interface & not implemented by partial view "
19411 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
19416 if Is_Tagged_Type (Priv_T)
19417 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19418 and then Is_Derived_Type (Full_T)
19420 Priv_Parent := Etype (Priv_T);
19422 -- The full view of a private extension may have been transformed
19423 -- into an unconstrained derived type declaration and a subtype
19424 -- declaration (see build_derived_record_type for details).
19426 if Nkind (N) = N_Subtype_Declaration then
19427 Full_Indic := Subtype_Indication (N);
19428 Full_Parent := Etype (Base_Type (Full_T));
19430 Full_Indic := Subtype_Indication (Type_Definition (N));
19431 Full_Parent := Etype (Full_T);
19434 -- Check that the parent type of the full type is a descendant of
19435 -- the ancestor subtype given in the private extension. If either
19436 -- entity has an Etype equal to Any_Type then we had some previous
19437 -- error situation [7.3(8)].
19439 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
19442 -- Ada 2005 (AI-251): Interfaces in the full type can be given in
19443 -- any order. Therefore we don't have to check that its parent must
19444 -- be a descendant of the parent of the private type declaration.
19446 elsif Is_Interface (Priv_Parent)
19447 and then Is_Interface (Full_Parent)
19451 -- Ada 2005 (AI-251): If the parent of the private type declaration
19452 -- is an interface there is no need to check that it is an ancestor
19453 -- of the associated full type declaration. The required tests for
19454 -- this case are performed by Build_Derived_Record_Type.
19456 elsif not Is_Interface (Base_Type (Priv_Parent))
19457 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
19460 ("parent of full type must descend from parent"
19461 & " of private extension", Full_Indic);
19463 -- First check a formal restriction, and then proceed with checking
19464 -- Ada rules. Since the formal restriction is not a serious error, we
19465 -- don't prevent further error detection for this check, hence the
19469 -- In formal mode, when completing a private extension the type
19470 -- named in the private part must be exactly the same as that
19471 -- named in the visible part.
19473 if Priv_Parent /= Full_Parent then
19474 Error_Msg_Name_1 := Chars (Priv_Parent);
19475 Check_SPARK_05_Restriction ("% expected", Full_Indic);
19478 -- Check the rules of 7.3(10): if the private extension inherits
19479 -- known discriminants, then the full type must also inherit those
19480 -- discriminants from the same (ancestor) type, and the parent
19481 -- subtype of the full type must be constrained if and only if
19482 -- the ancestor subtype of the private extension is constrained.
19484 if No (Discriminant_Specifications (Parent (Priv_T)))
19485 and then not Has_Unknown_Discriminants (Priv_T)
19486 and then Has_Discriminants (Base_Type (Priv_Parent))
19489 Priv_Indic : constant Node_Id :=
19490 Subtype_Indication (Parent (Priv_T));
19492 Priv_Constr : constant Boolean :=
19493 Is_Constrained (Priv_Parent)
19495 Nkind (Priv_Indic) = N_Subtype_Indication
19497 Is_Constrained (Entity (Priv_Indic));
19499 Full_Constr : constant Boolean :=
19500 Is_Constrained (Full_Parent)
19502 Nkind (Full_Indic) = N_Subtype_Indication
19504 Is_Constrained (Entity (Full_Indic));
19506 Priv_Discr : Entity_Id;
19507 Full_Discr : Entity_Id;
19510 Priv_Discr := First_Discriminant (Priv_Parent);
19511 Full_Discr := First_Discriminant (Full_Parent);
19512 while Present (Priv_Discr) and then Present (Full_Discr) loop
19513 if Original_Record_Component (Priv_Discr) =
19514 Original_Record_Component (Full_Discr)
19516 Corresponding_Discriminant (Priv_Discr) =
19517 Corresponding_Discriminant (Full_Discr)
19524 Next_Discriminant (Priv_Discr);
19525 Next_Discriminant (Full_Discr);
19528 if Present (Priv_Discr) or else Present (Full_Discr) then
19530 ("full view must inherit discriminants of the parent"
19531 & " type used in the private extension", Full_Indic);
19533 elsif Priv_Constr and then not Full_Constr then
19535 ("parent subtype of full type must be constrained",
19538 elsif Full_Constr and then not Priv_Constr then
19540 ("parent subtype of full type must be unconstrained",
19545 -- Check the rules of 7.3(12): if a partial view has neither
19546 -- known or unknown discriminants, then the full type
19547 -- declaration shall define a definite subtype.
19549 elsif not Has_Unknown_Discriminants (Priv_T)
19550 and then not Has_Discriminants (Priv_T)
19551 and then not Is_Constrained (Full_T)
19554 ("full view must define a constrained type if partial view"
19555 & " has no discriminants", Full_T);
19558 -- ??????? Do we implement the following properly ?????
19559 -- If the ancestor subtype of a private extension has constrained
19560 -- discriminants, then the parent subtype of the full view shall
19561 -- impose a statically matching constraint on those discriminants
19566 -- For untagged types, verify that a type without discriminants is
19567 -- not completed with an unconstrained type. A separate error message
19568 -- is produced if the full type has defaulted discriminants.
19570 if Is_Definite_Subtype (Priv_T)
19571 and then not Is_Definite_Subtype (Full_T)
19573 Error_Msg_Sloc := Sloc (Parent (Priv_T));
19575 ("full view of& not compatible with declaration#",
19578 if not Is_Tagged_Type (Full_T) then
19580 ("\one is constrained, the other unconstrained", Full_T);
19585 -- AI-419: verify that the use of "limited" is consistent
19588 Orig_Decl : constant Node_Id := Original_Node (N);
19591 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19592 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
19594 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
19596 if not Limited_Present (Parent (Priv_T))
19597 and then not Synchronized_Present (Parent (Priv_T))
19598 and then Limited_Present (Type_Definition (Orig_Decl))
19601 ("full view of non-limited extension cannot be limited", N);
19603 -- Conversely, if the partial view carries the limited keyword,
19604 -- the full view must as well, even if it may be redundant.
19606 elsif Limited_Present (Parent (Priv_T))
19607 and then not Limited_Present (Type_Definition (Orig_Decl))
19610 ("full view of limited extension must be explicitly limited",
19616 -- Ada 2005 (AI-443): A synchronized private extension must be
19617 -- completed by a task or protected type.
19619 if Ada_Version >= Ada_2005
19620 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19621 and then Synchronized_Present (Parent (Priv_T))
19622 and then not Is_Concurrent_Type (Full_T)
19624 Error_Msg_N ("full view of synchronized extension must " &
19625 "be synchronized type", N);
19628 -- Ada 2005 AI-363: if the full view has discriminants with
19629 -- defaults, it is illegal to declare constrained access subtypes
19630 -- whose designated type is the current type. This allows objects
19631 -- of the type that are declared in the heap to be unconstrained.
19633 if not Has_Unknown_Discriminants (Priv_T)
19634 and then not Has_Discriminants (Priv_T)
19635 and then Has_Discriminants (Full_T)
19637 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
19639 Set_Has_Constrained_Partial_View (Full_T);
19640 Set_Has_Constrained_Partial_View (Priv_T);
19643 -- Create a full declaration for all its subtypes recorded in
19644 -- Private_Dependents and swap them similarly to the base type. These
19645 -- are subtypes that have been define before the full declaration of
19646 -- the private type. We also swap the entry in Private_Dependents list
19647 -- so we can properly restore the private view on exit from the scope.
19650 Priv_Elmt : Elmt_Id;
19651 Priv_Scop : Entity_Id;
19656 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
19657 while Present (Priv_Elmt) loop
19658 Priv := Node (Priv_Elmt);
19659 Priv_Scop := Scope (Priv);
19661 if Ekind_In (Priv, E_Private_Subtype,
19662 E_Limited_Private_Subtype,
19663 E_Record_Subtype_With_Private)
19665 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
19666 Set_Is_Itype (Full);
19667 Set_Parent (Full, Parent (Priv));
19668 Set_Associated_Node_For_Itype (Full, N);
19670 -- Now we need to complete the private subtype, but since the
19671 -- base type has already been swapped, we must also swap the
19672 -- subtypes (and thus, reverse the arguments in the call to
19673 -- Complete_Private_Subtype). Also note that we may need to
19674 -- re-establish the scope of the private subtype.
19676 Copy_And_Swap (Priv, Full);
19678 if not In_Open_Scopes (Priv_Scop) then
19679 Push_Scope (Priv_Scop);
19682 -- Reset Priv_Scop to Empty to indicate no scope was pushed
19684 Priv_Scop := Empty;
19687 Complete_Private_Subtype (Full, Priv, Full_T, N);
19689 if Present (Priv_Scop) then
19693 Replace_Elmt (Priv_Elmt, Full);
19696 Next_Elmt (Priv_Elmt);
19700 -- If the private view was tagged, copy the new primitive operations
19701 -- from the private view to the full view.
19703 if Is_Tagged_Type (Full_T) then
19705 Disp_Typ : Entity_Id;
19706 Full_List : Elist_Id;
19708 Prim_Elmt : Elmt_Id;
19709 Priv_List : Elist_Id;
19713 L : Elist_Id) return Boolean;
19714 -- Determine whether list L contains element E
19722 L : Elist_Id) return Boolean
19724 List_Elmt : Elmt_Id;
19727 List_Elmt := First_Elmt (L);
19728 while Present (List_Elmt) loop
19729 if Node (List_Elmt) = E then
19733 Next_Elmt (List_Elmt);
19739 -- Start of processing
19742 if Is_Tagged_Type (Priv_T) then
19743 Priv_List := Primitive_Operations (Priv_T);
19744 Prim_Elmt := First_Elmt (Priv_List);
19746 -- In the case of a concurrent type completing a private tagged
19747 -- type, primitives may have been declared in between the two
19748 -- views. These subprograms need to be wrapped the same way
19749 -- entries and protected procedures are handled because they
19750 -- cannot be directly shared by the two views.
19752 if Is_Concurrent_Type (Full_T) then
19754 Conc_Typ : constant Entity_Id :=
19755 Corresponding_Record_Type (Full_T);
19756 Curr_Nod : Node_Id := Parent (Conc_Typ);
19757 Wrap_Spec : Node_Id;
19760 while Present (Prim_Elmt) loop
19761 Prim := Node (Prim_Elmt);
19763 if Comes_From_Source (Prim)
19764 and then not Is_Abstract_Subprogram (Prim)
19767 Make_Subprogram_Declaration (Sloc (Prim),
19771 Obj_Typ => Conc_Typ,
19773 Parameter_Specifications (
19776 Insert_After (Curr_Nod, Wrap_Spec);
19777 Curr_Nod := Wrap_Spec;
19779 Analyze (Wrap_Spec);
19782 Next_Elmt (Prim_Elmt);
19788 -- For non-concurrent types, transfer explicit primitives, but
19789 -- omit those inherited from the parent of the private view
19790 -- since they will be re-inherited later on.
19793 Full_List := Primitive_Operations (Full_T);
19795 while Present (Prim_Elmt) loop
19796 Prim := Node (Prim_Elmt);
19798 if Comes_From_Source (Prim)
19799 and then not Contains (Prim, Full_List)
19801 Append_Elmt (Prim, Full_List);
19804 Next_Elmt (Prim_Elmt);
19808 -- Untagged private view
19811 Full_List := Primitive_Operations (Full_T);
19813 -- In this case the partial view is untagged, so here we locate
19814 -- all of the earlier primitives that need to be treated as
19815 -- dispatching (those that appear between the two views). Note
19816 -- that these additional operations must all be new operations
19817 -- (any earlier operations that override inherited operations
19818 -- of the full view will already have been inserted in the
19819 -- primitives list, marked by Check_Operation_From_Private_View
19820 -- as dispatching. Note that implicit "/=" operators are
19821 -- excluded from being added to the primitives list since they
19822 -- shouldn't be treated as dispatching (tagged "/=" is handled
19825 Prim := Next_Entity (Full_T);
19826 while Present (Prim) and then Prim /= Priv_T loop
19827 if Ekind_In (Prim, E_Procedure, E_Function) then
19828 Disp_Typ := Find_Dispatching_Type (Prim);
19830 if Disp_Typ = Full_T
19831 and then (Chars (Prim) /= Name_Op_Ne
19832 or else Comes_From_Source (Prim))
19834 Check_Controlling_Formals (Full_T, Prim);
19836 if not Is_Dispatching_Operation (Prim) then
19837 Append_Elmt (Prim, Full_List);
19838 Set_Is_Dispatching_Operation (Prim, True);
19839 Set_DT_Position_Value (Prim, No_Uint);
19842 elsif Is_Dispatching_Operation (Prim)
19843 and then Disp_Typ /= Full_T
19846 -- Verify that it is not otherwise controlled by a
19847 -- formal or a return value of type T.
19849 Check_Controlling_Formals (Disp_Typ, Prim);
19853 Next_Entity (Prim);
19857 -- For the tagged case, the two views can share the same primitive
19858 -- operations list and the same class-wide type. Update attributes
19859 -- of the class-wide type which depend on the full declaration.
19861 if Is_Tagged_Type (Priv_T) then
19862 Set_Direct_Primitive_Operations (Priv_T, Full_List);
19863 Set_Class_Wide_Type
19864 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
19866 Set_Has_Task (Class_Wide_Type (Priv_T), Has_Task (Full_T));
19868 (Class_Wide_Type (Priv_T), Has_Protected (Full_T));
19873 -- Ada 2005 AI 161: Check preelaborable initialization consistency
19875 if Known_To_Have_Preelab_Init (Priv_T) then
19877 -- Case where there is a pragma Preelaborable_Initialization. We
19878 -- always allow this in predefined units, which is cheating a bit,
19879 -- but it means we don't have to struggle to meet the requirements in
19880 -- the RM for having Preelaborable Initialization. Otherwise we
19881 -- require that the type meets the RM rules. But we can't check that
19882 -- yet, because of the rule about overriding Initialize, so we simply
19883 -- set a flag that will be checked at freeze time.
19885 if not In_Predefined_Unit (Full_T) then
19886 Set_Must_Have_Preelab_Init (Full_T);
19890 -- If pragma CPP_Class was applied to the private type declaration,
19891 -- propagate it now to the full type declaration.
19893 if Is_CPP_Class (Priv_T) then
19894 Set_Is_CPP_Class (Full_T);
19895 Set_Convention (Full_T, Convention_CPP);
19897 -- Check that components of imported CPP types do not have default
19900 Check_CPP_Type_Has_No_Defaults (Full_T);
19903 -- If the private view has user specified stream attributes, then so has
19906 -- Why the test, how could these flags be already set in Full_T ???
19908 if Has_Specified_Stream_Read (Priv_T) then
19909 Set_Has_Specified_Stream_Read (Full_T);
19912 if Has_Specified_Stream_Write (Priv_T) then
19913 Set_Has_Specified_Stream_Write (Full_T);
19916 if Has_Specified_Stream_Input (Priv_T) then
19917 Set_Has_Specified_Stream_Input (Full_T);
19920 if Has_Specified_Stream_Output (Priv_T) then
19921 Set_Has_Specified_Stream_Output (Full_T);
19924 -- Propagate the attributes related to pragma Default_Initial_Condition
19925 -- from the private to the full view. Note that both flags are mutually
19928 if Has_Default_Init_Cond (Priv_T)
19929 or else Has_Inherited_Default_Init_Cond (Priv_T)
19931 Propagate_Default_Init_Cond_Attributes
19932 (From_Typ => Priv_T,
19934 Private_To_Full_View => True);
19936 -- In the case where the full view is derived from another private type,
19937 -- the attributes related to pragma Default_Initial_Condition must be
19938 -- propagated from the full to the private view to maintain consistency
19942 -- type Parent_Typ is private
19943 -- with Default_Initial_Condition ...;
19945 -- type Parent_Typ is ...;
19948 -- with Pack; use Pack;
19949 -- package Pack_2 is
19950 -- type Deriv_Typ is private; -- must inherit
19952 -- type Deriv_Typ is new Parent_Typ; -- must inherit
19955 elsif Has_Default_Init_Cond (Full_T)
19956 or else Has_Inherited_Default_Init_Cond (Full_T)
19958 Propagate_Default_Init_Cond_Attributes
19959 (From_Typ => Full_T,
19961 Private_To_Full_View => True);
19964 if Is_Ghost_Entity (Priv_T) then
19966 -- The Ghost policy in effect at the point of declaration and at the
19967 -- point of completion must match (SPARK RM 6.9(14)).
19969 Check_Ghost_Completion (Priv_T, Full_T);
19971 -- In the case where the private view of a tagged type lacks a parent
19972 -- type and is subject to pragma Ghost, ensure that the parent type
19973 -- specified by the full view is also Ghost (SPARK RM 6.9(9)).
19975 if Is_Derived_Type (Full_T) then
19976 Check_Ghost_Derivation (Full_T);
19979 -- Propagate the attributes related to pragma Ghost from the private
19980 -- to the full view.
19982 Mark_Full_View_As_Ghost (Priv_T, Full_T);
19985 -- Propagate invariants to full type
19987 if Has_Invariants (Priv_T) then
19988 Set_Has_Invariants (Full_T);
19989 Set_Invariant_Procedure (Full_T, Invariant_Procedure (Priv_T));
19992 if Has_Inheritable_Invariants (Priv_T) then
19993 Set_Has_Inheritable_Invariants (Full_T);
19996 -- Check hidden inheritance of class-wide type invariants
19998 if Ada_Version >= Ada_2012
19999 and then not Has_Inheritable_Invariants (Full_T)
20000 and then In_Private_Part (Current_Scope)
20001 and then Has_Interfaces (Full_T)
20008 Collect_Interfaces (Full_T, Ifaces, Exclude_Parents => True);
20010 AI := First_Elmt (Ifaces);
20011 while Present (AI) loop
20012 if Has_Inheritable_Invariants (Node (AI)) then
20014 ("hidden inheritance of class-wide type invariants " &
20024 -- Propagate predicates to full type, and predicate function if already
20025 -- defined. It is not clear that this can actually happen? the partial
20026 -- view cannot be frozen yet, and the predicate function has not been
20027 -- built. Still it is a cheap check and seems safer to make it.
20029 if Has_Predicates (Priv_T) then
20030 if Present (Predicate_Function (Priv_T)) then
20031 Set_Predicate_Function (Full_T, Predicate_Function (Priv_T));
20034 Set_Has_Predicates (Full_T);
20036 end Process_Full_View;
20038 -----------------------------------
20039 -- Process_Incomplete_Dependents --
20040 -----------------------------------
20042 procedure Process_Incomplete_Dependents
20044 Full_T : Entity_Id;
20047 Inc_Elmt : Elmt_Id;
20048 Priv_Dep : Entity_Id;
20049 New_Subt : Entity_Id;
20051 Disc_Constraint : Elist_Id;
20054 if No (Private_Dependents (Inc_T)) then
20058 -- Itypes that may be generated by the completion of an incomplete
20059 -- subtype are not used by the back-end and not attached to the tree.
20060 -- They are created only for constraint-checking purposes.
20062 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
20063 while Present (Inc_Elmt) loop
20064 Priv_Dep := Node (Inc_Elmt);
20066 if Ekind (Priv_Dep) = E_Subprogram_Type then
20068 -- An Access_To_Subprogram type may have a return type or a
20069 -- parameter type that is incomplete. Replace with the full view.
20071 if Etype (Priv_Dep) = Inc_T then
20072 Set_Etype (Priv_Dep, Full_T);
20076 Formal : Entity_Id;
20079 Formal := First_Formal (Priv_Dep);
20080 while Present (Formal) loop
20081 if Etype (Formal) = Inc_T then
20082 Set_Etype (Formal, Full_T);
20085 Next_Formal (Formal);
20089 elsif Is_Overloadable (Priv_Dep) then
20091 -- If a subprogram in the incomplete dependents list is primitive
20092 -- for a tagged full type then mark it as a dispatching operation,
20093 -- check whether it overrides an inherited subprogram, and check
20094 -- restrictions on its controlling formals. Note that a protected
20095 -- operation is never dispatching: only its wrapper operation
20096 -- (which has convention Ada) is.
20098 if Is_Tagged_Type (Full_T)
20099 and then Is_Primitive (Priv_Dep)
20100 and then Convention (Priv_Dep) /= Convention_Protected
20102 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
20103 Set_Is_Dispatching_Operation (Priv_Dep);
20104 Check_Controlling_Formals (Full_T, Priv_Dep);
20107 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
20109 -- Can happen during processing of a body before the completion
20110 -- of a TA type. Ignore, because spec is also on dependent list.
20114 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
20115 -- corresponding subtype of the full view.
20117 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype then
20118 Set_Subtype_Indication
20119 (Parent (Priv_Dep), New_Occurrence_Of (Full_T, Sloc (Priv_Dep)));
20120 Set_Etype (Priv_Dep, Full_T);
20121 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
20122 Set_Analyzed (Parent (Priv_Dep), False);
20124 -- Reanalyze the declaration, suppressing the call to
20125 -- Enter_Name to avoid duplicate names.
20127 Analyze_Subtype_Declaration
20128 (N => Parent (Priv_Dep),
20131 -- Dependent is a subtype
20134 -- We build a new subtype indication using the full view of the
20135 -- incomplete parent. The discriminant constraints have been
20136 -- elaborated already at the point of the subtype declaration.
20138 New_Subt := Create_Itype (E_Void, N);
20140 if Has_Discriminants (Full_T) then
20141 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
20143 Disc_Constraint := No_Elist;
20146 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
20147 Set_Full_View (Priv_Dep, New_Subt);
20150 Next_Elmt (Inc_Elmt);
20152 end Process_Incomplete_Dependents;
20154 --------------------------------
20155 -- Process_Range_Expr_In_Decl --
20156 --------------------------------
20158 procedure Process_Range_Expr_In_Decl
20161 Subtyp : Entity_Id := Empty;
20162 Check_List : List_Id := Empty_List;
20163 R_Check_Off : Boolean := False;
20164 In_Iter_Schm : Boolean := False)
20167 R_Checks : Check_Result;
20168 Insert_Node : Node_Id;
20169 Def_Id : Entity_Id;
20172 Analyze_And_Resolve (R, Base_Type (T));
20174 if Nkind (R) = N_Range then
20176 -- In SPARK, all ranges should be static, with the exception of the
20177 -- discrete type definition of a loop parameter specification.
20179 if not In_Iter_Schm
20180 and then not Is_OK_Static_Range (R)
20182 Check_SPARK_05_Restriction ("range should be static", R);
20185 Lo := Low_Bound (R);
20186 Hi := High_Bound (R);
20188 -- Validity checks on the range of a quantified expression are
20189 -- delayed until the construct is transformed into a loop.
20191 if Nkind (Parent (R)) = N_Loop_Parameter_Specification
20192 and then Nkind (Parent (Parent (R))) = N_Quantified_Expression
20196 -- We need to ensure validity of the bounds here, because if we
20197 -- go ahead and do the expansion, then the expanded code will get
20198 -- analyzed with range checks suppressed and we miss the check.
20200 -- WARNING: The capture of the range bounds with xxx_FIRST/_LAST and
20201 -- the temporaries generated by routine Remove_Side_Effects by means
20202 -- of validity checks must use the same names. When a range appears
20203 -- in the parent of a generic, the range is processed with checks
20204 -- disabled as part of the generic context and with checks enabled
20205 -- for code generation purposes. This leads to link issues as the
20206 -- generic contains references to xxx_FIRST/_LAST, but the inlined
20207 -- template sees the temporaries generated by Remove_Side_Effects.
20210 Validity_Check_Range (R, Subtyp);
20213 -- If there were errors in the declaration, try and patch up some
20214 -- common mistakes in the bounds. The cases handled are literals
20215 -- which are Integer where the expected type is Real and vice versa.
20216 -- These corrections allow the compilation process to proceed further
20217 -- along since some basic assumptions of the format of the bounds
20220 if Etype (R) = Any_Type then
20221 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
20223 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
20225 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
20227 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
20229 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
20231 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
20233 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
20235 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
20242 -- If the bounds of the range have been mistakenly given as string
20243 -- literals (perhaps in place of character literals), then an error
20244 -- has already been reported, but we rewrite the string literal as a
20245 -- bound of the range's type to avoid blowups in later processing
20246 -- that looks at static values.
20248 if Nkind (Lo) = N_String_Literal then
20250 Make_Attribute_Reference (Sloc (Lo),
20251 Prefix => New_Occurrence_Of (T, Sloc (Lo)),
20252 Attribute_Name => Name_First));
20253 Analyze_And_Resolve (Lo);
20256 if Nkind (Hi) = N_String_Literal then
20258 Make_Attribute_Reference (Sloc (Hi),
20259 Prefix => New_Occurrence_Of (T, Sloc (Hi)),
20260 Attribute_Name => Name_First));
20261 Analyze_And_Resolve (Hi);
20264 -- If bounds aren't scalar at this point then exit, avoiding
20265 -- problems with further processing of the range in this procedure.
20267 if not Is_Scalar_Type (Etype (Lo)) then
20271 -- Resolve (actually Sem_Eval) has checked that the bounds are in
20272 -- then range of the base type. Here we check whether the bounds
20273 -- are in the range of the subtype itself. Note that if the bounds
20274 -- represent the null range the Constraint_Error exception should
20277 -- ??? The following code should be cleaned up as follows
20279 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
20280 -- is done in the call to Range_Check (R, T); below
20282 -- 2. The use of R_Check_Off should be investigated and possibly
20283 -- removed, this would clean up things a bit.
20285 if Is_Null_Range (Lo, Hi) then
20289 -- Capture values of bounds and generate temporaries for them
20290 -- if needed, before applying checks, since checks may cause
20291 -- duplication of the expression without forcing evaluation.
20293 -- The forced evaluation removes side effects from expressions,
20294 -- which should occur also in GNATprove mode. Otherwise, we end up
20295 -- with unexpected insertions of actions at places where this is
20296 -- not supposed to occur, e.g. on default parameters of a call.
20298 if Expander_Active or GNATprove_Mode then
20300 -- Call Force_Evaluation to create declarations as needed to
20301 -- deal with side effects, and also create typ_FIRST/LAST
20302 -- entities for bounds if we have a subtype name.
20304 -- Note: we do this transformation even if expansion is not
20305 -- active if we are in GNATprove_Mode since the transformation
20306 -- is in general required to ensure that the resulting tree has
20307 -- proper Ada semantics.
20310 (Lo, Related_Id => Subtyp, Is_Low_Bound => True);
20312 (Hi, Related_Id => Subtyp, Is_High_Bound => True);
20315 -- We use a flag here instead of suppressing checks on the type
20316 -- because the type we check against isn't necessarily the place
20317 -- where we put the check.
20319 if not R_Check_Off then
20320 R_Checks := Get_Range_Checks (R, T);
20322 -- Look up tree to find an appropriate insertion point. We
20323 -- can't just use insert_actions because later processing
20324 -- depends on the insertion node. Prior to Ada 2012 the
20325 -- insertion point could only be a declaration or a loop, but
20326 -- quantified expressions can appear within any context in an
20327 -- expression, and the insertion point can be any statement,
20328 -- pragma, or declaration.
20330 Insert_Node := Parent (R);
20331 while Present (Insert_Node) loop
20333 Nkind (Insert_Node) in N_Declaration
20336 (Insert_Node, N_Component_Declaration,
20337 N_Loop_Parameter_Specification,
20338 N_Function_Specification,
20339 N_Procedure_Specification);
20341 exit when Nkind (Insert_Node) in N_Later_Decl_Item
20342 or else Nkind (Insert_Node) in
20343 N_Statement_Other_Than_Procedure_Call
20344 or else Nkind_In (Insert_Node, N_Procedure_Call_Statement,
20347 Insert_Node := Parent (Insert_Node);
20350 -- Why would Type_Decl not be present??? Without this test,
20351 -- short regression tests fail.
20353 if Present (Insert_Node) then
20355 -- Case of loop statement. Verify that the range is part
20356 -- of the subtype indication of the iteration scheme.
20358 if Nkind (Insert_Node) = N_Loop_Statement then
20363 Indic := Parent (R);
20364 while Present (Indic)
20365 and then Nkind (Indic) /= N_Subtype_Indication
20367 Indic := Parent (Indic);
20370 if Present (Indic) then
20371 Def_Id := Etype (Subtype_Mark (Indic));
20373 Insert_Range_Checks
20377 Sloc (Insert_Node),
20379 Do_Before => True);
20383 -- Insertion before a declaration. If the declaration
20384 -- includes discriminants, the list of applicable checks
20385 -- is given by the caller.
20387 elsif Nkind (Insert_Node) in N_Declaration then
20388 Def_Id := Defining_Identifier (Insert_Node);
20390 if (Ekind (Def_Id) = E_Record_Type
20391 and then Depends_On_Discriminant (R))
20393 (Ekind (Def_Id) = E_Protected_Type
20394 and then Has_Discriminants (Def_Id))
20396 Append_Range_Checks
20398 Check_List, Def_Id, Sloc (Insert_Node), R);
20401 Insert_Range_Checks
20403 Insert_Node, Def_Id, Sloc (Insert_Node), R);
20407 -- Insertion before a statement. Range appears in the
20408 -- context of a quantified expression. Insertion will
20409 -- take place when expression is expanded.
20418 -- Case of other than an explicit N_Range node
20420 -- The forced evaluation removes side effects from expressions, which
20421 -- should occur also in GNATprove mode. Otherwise, we end up with
20422 -- unexpected insertions of actions at places where this is not
20423 -- supposed to occur, e.g. on default parameters of a call.
20425 elsif Expander_Active or GNATprove_Mode then
20426 Get_Index_Bounds (R, Lo, Hi);
20427 Force_Evaluation (Lo);
20428 Force_Evaluation (Hi);
20430 end Process_Range_Expr_In_Decl;
20432 --------------------------------------
20433 -- Process_Real_Range_Specification --
20434 --------------------------------------
20436 procedure Process_Real_Range_Specification (Def : Node_Id) is
20437 Spec : constant Node_Id := Real_Range_Specification (Def);
20440 Err : Boolean := False;
20442 procedure Analyze_Bound (N : Node_Id);
20443 -- Analyze and check one bound
20445 -------------------
20446 -- Analyze_Bound --
20447 -------------------
20449 procedure Analyze_Bound (N : Node_Id) is
20451 Analyze_And_Resolve (N, Any_Real);
20453 if not Is_OK_Static_Expression (N) then
20454 Flag_Non_Static_Expr
20455 ("bound in real type definition is not static!", N);
20460 -- Start of processing for Process_Real_Range_Specification
20463 if Present (Spec) then
20464 Lo := Low_Bound (Spec);
20465 Hi := High_Bound (Spec);
20466 Analyze_Bound (Lo);
20467 Analyze_Bound (Hi);
20469 -- If error, clear away junk range specification
20472 Set_Real_Range_Specification (Def, Empty);
20475 end Process_Real_Range_Specification;
20477 ---------------------
20478 -- Process_Subtype --
20479 ---------------------
20481 function Process_Subtype
20483 Related_Nod : Node_Id;
20484 Related_Id : Entity_Id := Empty;
20485 Suffix : Character := ' ') return Entity_Id
20488 Def_Id : Entity_Id;
20489 Error_Node : Node_Id;
20490 Full_View_Id : Entity_Id;
20491 Subtype_Mark_Id : Entity_Id;
20493 May_Have_Null_Exclusion : Boolean;
20495 procedure Check_Incomplete (T : Entity_Id);
20496 -- Called to verify that an incomplete type is not used prematurely
20498 ----------------------
20499 -- Check_Incomplete --
20500 ----------------------
20502 procedure Check_Incomplete (T : Entity_Id) is
20504 -- Ada 2005 (AI-412): Incomplete subtypes are legal
20506 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
20508 not (Ada_Version >= Ada_2005
20510 (Nkind (Parent (T)) = N_Subtype_Declaration
20511 or else (Nkind (Parent (T)) = N_Subtype_Indication
20512 and then Nkind (Parent (Parent (T))) =
20513 N_Subtype_Declaration)))
20515 Error_Msg_N ("invalid use of type before its full declaration", T);
20517 end Check_Incomplete;
20519 -- Start of processing for Process_Subtype
20522 -- Case of no constraints present
20524 if Nkind (S) /= N_Subtype_Indication then
20526 Check_Incomplete (S);
20529 -- Ada 2005 (AI-231): Static check
20531 if Ada_Version >= Ada_2005
20532 and then Present (P)
20533 and then Null_Exclusion_Present (P)
20534 and then Nkind (P) /= N_Access_To_Object_Definition
20535 and then not Is_Access_Type (Entity (S))
20537 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
20540 -- The following is ugly, can't we have a range or even a flag???
20542 May_Have_Null_Exclusion :=
20543 Nkind_In (P, N_Access_Definition,
20544 N_Access_Function_Definition,
20545 N_Access_Procedure_Definition,
20546 N_Access_To_Object_Definition,
20548 N_Component_Definition)
20550 Nkind_In (P, N_Derived_Type_Definition,
20551 N_Discriminant_Specification,
20552 N_Formal_Object_Declaration,
20553 N_Object_Declaration,
20554 N_Object_Renaming_Declaration,
20555 N_Parameter_Specification,
20556 N_Subtype_Declaration);
20558 -- Create an Itype that is a duplicate of Entity (S) but with the
20559 -- null-exclusion attribute.
20561 if May_Have_Null_Exclusion
20562 and then Is_Access_Type (Entity (S))
20563 and then Null_Exclusion_Present (P)
20565 -- No need to check the case of an access to object definition.
20566 -- It is correct to define double not-null pointers.
20569 -- type Not_Null_Int_Ptr is not null access Integer;
20570 -- type Acc is not null access Not_Null_Int_Ptr;
20572 and then Nkind (P) /= N_Access_To_Object_Definition
20574 if Can_Never_Be_Null (Entity (S)) then
20575 case Nkind (Related_Nod) is
20576 when N_Full_Type_Declaration =>
20577 if Nkind (Type_Definition (Related_Nod))
20578 in N_Array_Type_Definition
20582 (Component_Definition
20583 (Type_Definition (Related_Nod)));
20586 Subtype_Indication (Type_Definition (Related_Nod));
20589 when N_Subtype_Declaration =>
20590 Error_Node := Subtype_Indication (Related_Nod);
20592 when N_Object_Declaration =>
20593 Error_Node := Object_Definition (Related_Nod);
20595 when N_Component_Declaration =>
20597 Subtype_Indication (Component_Definition (Related_Nod));
20599 when N_Allocator =>
20600 Error_Node := Expression (Related_Nod);
20603 pragma Assert (False);
20604 Error_Node := Related_Nod;
20608 ("`NOT NULL` not allowed (& already excludes null)",
20614 Create_Null_Excluding_Itype
20616 Related_Nod => P));
20617 Set_Entity (S, Etype (S));
20622 -- Case of constraint present, so that we have an N_Subtype_Indication
20623 -- node (this node is created only if constraints are present).
20626 Find_Type (Subtype_Mark (S));
20628 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
20630 (Nkind (Parent (S)) = N_Subtype_Declaration
20631 and then Is_Itype (Defining_Identifier (Parent (S))))
20633 Check_Incomplete (Subtype_Mark (S));
20637 Subtype_Mark_Id := Entity (Subtype_Mark (S));
20639 -- Explicit subtype declaration case
20641 if Nkind (P) = N_Subtype_Declaration then
20642 Def_Id := Defining_Identifier (P);
20644 -- Explicit derived type definition case
20646 elsif Nkind (P) = N_Derived_Type_Definition then
20647 Def_Id := Defining_Identifier (Parent (P));
20649 -- Implicit case, the Def_Id must be created as an implicit type.
20650 -- The one exception arises in the case of concurrent types, array
20651 -- and access types, where other subsidiary implicit types may be
20652 -- created and must appear before the main implicit type. In these
20653 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
20654 -- has not yet been called to create Def_Id.
20657 if Is_Array_Type (Subtype_Mark_Id)
20658 or else Is_Concurrent_Type (Subtype_Mark_Id)
20659 or else Is_Access_Type (Subtype_Mark_Id)
20663 -- For the other cases, we create a new unattached Itype,
20664 -- and set the indication to ensure it gets attached later.
20668 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
20672 -- If the kind of constraint is invalid for this kind of type,
20673 -- then give an error, and then pretend no constraint was given.
20675 if not Is_Valid_Constraint_Kind
20676 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
20679 ("incorrect constraint for this kind of type", Constraint (S));
20681 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
20683 -- Set Ekind of orphan itype, to prevent cascaded errors
20685 if Present (Def_Id) then
20686 Set_Ekind (Def_Id, Ekind (Any_Type));
20689 -- Make recursive call, having got rid of the bogus constraint
20691 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
20694 -- Remaining processing depends on type. Select on Base_Type kind to
20695 -- ensure getting to the concrete type kind in the case of a private
20696 -- subtype (needed when only doing semantic analysis).
20698 case Ekind (Base_Type (Subtype_Mark_Id)) is
20699 when Access_Kind =>
20701 -- If this is a constraint on a class-wide type, discard it.
20702 -- There is currently no way to express a partial discriminant
20703 -- constraint on a type with unknown discriminants. This is
20704 -- a pathology that the ACATS wisely decides not to test.
20706 if Is_Class_Wide_Type (Designated_Type (Subtype_Mark_Id)) then
20707 if Comes_From_Source (S) then
20709 ("constraint on class-wide type ignored??",
20713 if Nkind (P) = N_Subtype_Declaration then
20714 Set_Subtype_Indication (P,
20715 New_Occurrence_Of (Subtype_Mark_Id, Sloc (S)));
20718 return Subtype_Mark_Id;
20721 Constrain_Access (Def_Id, S, Related_Nod);
20724 and then Is_Itype (Designated_Type (Def_Id))
20725 and then Nkind (Related_Nod) = N_Subtype_Declaration
20726 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
20728 Build_Itype_Reference
20729 (Designated_Type (Def_Id), Related_Nod);
20733 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
20735 when Decimal_Fixed_Point_Kind =>
20736 Constrain_Decimal (Def_Id, S);
20738 when Enumeration_Kind =>
20739 Constrain_Enumeration (Def_Id, S);
20740 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
20742 when Ordinary_Fixed_Point_Kind =>
20743 Constrain_Ordinary_Fixed (Def_Id, S);
20746 Constrain_Float (Def_Id, S);
20748 when Integer_Kind =>
20749 Constrain_Integer (Def_Id, S);
20750 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
20752 when E_Record_Type |
20755 E_Incomplete_Type =>
20756 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
20758 if Ekind (Def_Id) = E_Incomplete_Type then
20759 Set_Private_Dependents (Def_Id, New_Elmt_List);
20762 when Private_Kind =>
20763 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
20764 Set_Private_Dependents (Def_Id, New_Elmt_List);
20766 -- In case of an invalid constraint prevent further processing
20767 -- since the type constructed is missing expected fields.
20769 if Etype (Def_Id) = Any_Type then
20773 -- If the full view is that of a task with discriminants,
20774 -- we must constrain both the concurrent type and its
20775 -- corresponding record type. Otherwise we will just propagate
20776 -- the constraint to the full view, if available.
20778 if Present (Full_View (Subtype_Mark_Id))
20779 and then Has_Discriminants (Subtype_Mark_Id)
20780 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
20783 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
20785 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
20786 Constrain_Concurrent (Full_View_Id, S,
20787 Related_Nod, Related_Id, Suffix);
20788 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
20789 Set_Full_View (Def_Id, Full_View_Id);
20791 -- Introduce an explicit reference to the private subtype,
20792 -- to prevent scope anomalies in gigi if first use appears
20793 -- in a nested context, e.g. a later function body.
20794 -- Should this be generated in other contexts than a full
20795 -- type declaration?
20797 if Is_Itype (Def_Id)
20799 Nkind (Parent (P)) = N_Full_Type_Declaration
20801 Build_Itype_Reference (Def_Id, Parent (P));
20805 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
20808 when Concurrent_Kind =>
20809 Constrain_Concurrent (Def_Id, S,
20810 Related_Nod, Related_Id, Suffix);
20813 Error_Msg_N ("invalid subtype mark in subtype indication", S);
20816 -- Size and Convention are always inherited from the base type
20818 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
20819 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
20823 end Process_Subtype;
20825 --------------------------------------------
20826 -- Propagate_Default_Init_Cond_Attributes --
20827 --------------------------------------------
20829 procedure Propagate_Default_Init_Cond_Attributes
20830 (From_Typ : Entity_Id;
20831 To_Typ : Entity_Id;
20832 Parent_To_Derivation : Boolean := False;
20833 Private_To_Full_View : Boolean := False)
20835 procedure Remove_Default_Init_Cond_Procedure (Typ : Entity_Id);
20836 -- Remove the default initial procedure (if any) from the rep chain of
20839 ----------------------------------------
20840 -- Remove_Default_Init_Cond_Procedure --
20841 ----------------------------------------
20843 procedure Remove_Default_Init_Cond_Procedure (Typ : Entity_Id) is
20844 Found : Boolean := False;
20850 Subp := Subprograms_For_Type (Typ);
20851 while Present (Subp) loop
20852 if Is_Default_Init_Cond_Procedure (Subp) then
20858 Subp := Subprograms_For_Type (Subp);
20862 Set_Subprograms_For_Type (Prev, Subprograms_For_Type (Subp));
20863 Set_Subprograms_For_Type (Subp, Empty);
20865 end Remove_Default_Init_Cond_Procedure;
20869 Inherit_Procedure : Boolean := False;
20871 -- Start of processing for Propagate_Default_Init_Cond_Attributes
20874 if Has_Default_Init_Cond (From_Typ) then
20876 -- A derived type inherits the attributes from its parent type
20878 if Parent_To_Derivation then
20879 Set_Has_Inherited_Default_Init_Cond (To_Typ);
20881 -- A full view shares the attributes with its private view
20884 Set_Has_Default_Init_Cond (To_Typ);
20887 Inherit_Procedure := True;
20889 -- Due to the order of expansion, a derived private type is processed
20890 -- by two routines which both attempt to set the attributes related
20891 -- to pragma Default_Initial_Condition - Build_Derived_Type and then
20892 -- Process_Full_View.
20895 -- type Parent_Typ is private
20896 -- with Default_Initial_Condition ...;
20898 -- type Parent_Typ is ...;
20901 -- with Pack; use Pack;
20902 -- package Pack_2 is
20903 -- type Deriv_Typ is private
20904 -- with Default_Initial_Condition ...;
20906 -- type Deriv_Typ is new Parent_Typ;
20909 -- When Build_Derived_Type operates, it sets the attributes on the
20910 -- full view without taking into account that the private view may
20911 -- define its own default initial condition procedure. This becomes
20912 -- apparent in Process_Full_View which must undo some of the work by
20913 -- Build_Derived_Type and propagate the attributes from the private
20914 -- to the full view.
20916 if Private_To_Full_View then
20917 Set_Has_Inherited_Default_Init_Cond (To_Typ, False);
20918 Remove_Default_Init_Cond_Procedure (To_Typ);
20921 -- A type must inherit the default initial condition procedure from a
20922 -- parent type when the parent itself is inheriting the procedure or
20923 -- when it is defining one. This circuitry is also used when dealing
20924 -- with the private / full view of a type.
20926 elsif Has_Inherited_Default_Init_Cond (From_Typ)
20927 or (Parent_To_Derivation
20928 and Present (Get_Pragma
20929 (From_Typ, Pragma_Default_Initial_Condition)))
20931 Set_Has_Inherited_Default_Init_Cond (To_Typ);
20932 Inherit_Procedure := True;
20935 if Inherit_Procedure
20936 and then No (Default_Init_Cond_Procedure (To_Typ))
20938 Set_Default_Init_Cond_Procedure
20939 (To_Typ, Default_Init_Cond_Procedure (From_Typ));
20941 end Propagate_Default_Init_Cond_Attributes;
20943 -----------------------------
20944 -- Record_Type_Declaration --
20945 -----------------------------
20947 procedure Record_Type_Declaration
20952 Def : constant Node_Id := Type_Definition (N);
20953 Is_Tagged : Boolean;
20954 Tag_Comp : Entity_Id;
20957 -- These flags must be initialized before calling Process_Discriminants
20958 -- because this routine makes use of them.
20960 Set_Ekind (T, E_Record_Type);
20962 Init_Size_Align (T);
20963 Set_Interfaces (T, No_Elist);
20964 Set_Stored_Constraint (T, No_Elist);
20965 Set_Default_SSO (T);
20969 if Ada_Version < Ada_2005 or else not Interface_Present (Def) then
20970 if Limited_Present (Def) then
20971 Check_SPARK_05_Restriction ("limited is not allowed", N);
20974 if Abstract_Present (Def) then
20975 Check_SPARK_05_Restriction ("abstract is not allowed", N);
20978 -- The flag Is_Tagged_Type might have already been set by
20979 -- Find_Type_Name if it detected an error for declaration T. This
20980 -- arises in the case of private tagged types where the full view
20981 -- omits the word tagged.
20984 Tagged_Present (Def)
20985 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
20987 Set_Is_Limited_Record (T, Limited_Present (Def));
20990 Set_Is_Tagged_Type (T, True);
20991 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
20994 -- Type is abstract if full declaration carries keyword, or if
20995 -- previous partial view did.
20997 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
20998 or else Abstract_Present (Def));
21001 Check_SPARK_05_Restriction ("interface is not allowed", N);
21004 Analyze_Interface_Declaration (T, Def);
21006 if Present (Discriminant_Specifications (N)) then
21008 ("interface types cannot have discriminants",
21009 Defining_Identifier
21010 (First (Discriminant_Specifications (N))));
21014 -- First pass: if there are self-referential access components,
21015 -- create the required anonymous access type declarations, and if
21016 -- need be an incomplete type declaration for T itself.
21018 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
21020 if Ada_Version >= Ada_2005
21021 and then Present (Interface_List (Def))
21023 Check_Interfaces (N, Def);
21026 Ifaces_List : Elist_Id;
21029 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
21030 -- already in the parents.
21034 Ifaces_List => Ifaces_List,
21035 Exclude_Parents => True);
21037 Set_Interfaces (T, Ifaces_List);
21041 -- Records constitute a scope for the component declarations within.
21042 -- The scope is created prior to the processing of these declarations.
21043 -- Discriminants are processed first, so that they are visible when
21044 -- processing the other components. The Ekind of the record type itself
21045 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
21047 -- Enter record scope
21051 -- If an incomplete or private type declaration was already given for
21052 -- the type, then this scope already exists, and the discriminants have
21053 -- been declared within. We must verify that the full declaration
21054 -- matches the incomplete one.
21056 Check_Or_Process_Discriminants (N, T, Prev);
21058 Set_Is_Constrained (T, not Has_Discriminants (T));
21059 Set_Has_Delayed_Freeze (T, True);
21061 -- For tagged types add a manually analyzed component corresponding
21062 -- to the component _tag, the corresponding piece of tree will be
21063 -- expanded as part of the freezing actions if it is not a CPP_Class.
21067 -- Do not add the tag unless we are in expansion mode
21069 if Expander_Active then
21070 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
21071 Enter_Name (Tag_Comp);
21073 Set_Ekind (Tag_Comp, E_Component);
21074 Set_Is_Tag (Tag_Comp);
21075 Set_Is_Aliased (Tag_Comp);
21076 Set_Etype (Tag_Comp, RTE (RE_Tag));
21077 Set_DT_Entry_Count (Tag_Comp, No_Uint);
21078 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
21079 Init_Component_Location (Tag_Comp);
21081 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
21082 -- implemented interfaces.
21084 if Has_Interfaces (T) then
21085 Add_Interface_Tag_Components (N, T);
21089 Make_Class_Wide_Type (T);
21090 Set_Direct_Primitive_Operations (T, New_Elmt_List);
21093 -- We must suppress range checks when processing record components in
21094 -- the presence of discriminants, since we don't want spurious checks to
21095 -- be generated during their analysis, but Suppress_Range_Checks flags
21096 -- must be reset the after processing the record definition.
21098 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
21099 -- couldn't we just use the normal range check suppression method here.
21100 -- That would seem cleaner ???
21102 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
21103 Set_Kill_Range_Checks (T, True);
21104 Record_Type_Definition (Def, Prev);
21105 Set_Kill_Range_Checks (T, False);
21107 Record_Type_Definition (Def, Prev);
21110 -- Exit from record scope
21114 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
21115 -- the implemented interfaces and associate them an aliased entity.
21118 and then not Is_Empty_List (Interface_List (Def))
21120 Derive_Progenitor_Subprograms (T, T);
21123 Check_Function_Writable_Actuals (N);
21124 end Record_Type_Declaration;
21126 ----------------------------
21127 -- Record_Type_Definition --
21128 ----------------------------
21130 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
21131 Component : Entity_Id;
21132 Ctrl_Components : Boolean := False;
21133 Final_Storage_Only : Boolean;
21137 if Ekind (Prev_T) = E_Incomplete_Type then
21138 T := Full_View (Prev_T);
21143 -- In SPARK, tagged types and type extensions may only be declared in
21144 -- the specification of library unit packages.
21146 if Present (Def) and then Is_Tagged_Type (T) then
21152 if Nkind (Parent (Def)) = N_Full_Type_Declaration then
21153 Typ := Parent (Def);
21156 (Nkind (Parent (Def)) = N_Derived_Type_Definition);
21157 Typ := Parent (Parent (Def));
21160 Ctxt := Parent (Typ);
21162 if Nkind (Ctxt) = N_Package_Body
21163 and then Nkind (Parent (Ctxt)) = N_Compilation_Unit
21165 Check_SPARK_05_Restriction
21166 ("type should be defined in package specification", Typ);
21168 elsif Nkind (Ctxt) /= N_Package_Specification
21169 or else Nkind (Parent (Parent (Ctxt))) /= N_Compilation_Unit
21171 Check_SPARK_05_Restriction
21172 ("type should be defined in library unit package", Typ);
21177 Final_Storage_Only := not Is_Controlled_Active (T);
21179 -- Ada 2005: Check whether an explicit Limited is present in a derived
21180 -- type declaration.
21182 if Nkind (Parent (Def)) = N_Derived_Type_Definition
21183 and then Limited_Present (Parent (Def))
21185 Set_Is_Limited_Record (T);
21188 -- If the component list of a record type is defined by the reserved
21189 -- word null and there is no discriminant part, then the record type has
21190 -- no components and all records of the type are null records (RM 3.7)
21191 -- This procedure is also called to process the extension part of a
21192 -- record extension, in which case the current scope may have inherited
21196 or else No (Component_List (Def))
21197 or else Null_Present (Component_List (Def))
21199 if not Is_Tagged_Type (T) then
21200 Check_SPARK_05_Restriction ("untagged record cannot be null", Def);
21204 Analyze_Declarations (Component_Items (Component_List (Def)));
21206 if Present (Variant_Part (Component_List (Def))) then
21207 Check_SPARK_05_Restriction ("variant part is not allowed", Def);
21208 Analyze (Variant_Part (Component_List (Def)));
21212 -- After completing the semantic analysis of the record definition,
21213 -- record components, both new and inherited, are accessible. Set their
21214 -- kind accordingly. Exclude malformed itypes from illegal declarations,
21215 -- whose Ekind may be void.
21217 Component := First_Entity (Current_Scope);
21218 while Present (Component) loop
21219 if Ekind (Component) = E_Void
21220 and then not Is_Itype (Component)
21222 Set_Ekind (Component, E_Component);
21223 Init_Component_Location (Component);
21226 if Has_Task (Etype (Component)) then
21230 if Has_Protected (Etype (Component)) then
21231 Set_Has_Protected (T);
21234 if Ekind (Component) /= E_Component then
21237 -- Do not set Has_Controlled_Component on a class-wide equivalent
21238 -- type. See Make_CW_Equivalent_Type.
21240 elsif not Is_Class_Wide_Equivalent_Type (T)
21241 and then (Has_Controlled_Component (Etype (Component))
21242 or else (Chars (Component) /= Name_uParent
21243 and then Is_Controlled_Active
21244 (Etype (Component))))
21246 Set_Has_Controlled_Component (T, True);
21247 Final_Storage_Only :=
21249 and then Finalize_Storage_Only (Etype (Component));
21250 Ctrl_Components := True;
21253 Next_Entity (Component);
21256 -- A Type is Finalize_Storage_Only only if all its controlled components
21259 if Ctrl_Components then
21260 Set_Finalize_Storage_Only (T, Final_Storage_Only);
21263 -- Place reference to end record on the proper entity, which may
21264 -- be a partial view.
21266 if Present (Def) then
21267 Process_End_Label (Def, 'e', Prev_T);
21269 end Record_Type_Definition;
21271 ------------------------
21272 -- Replace_Components --
21273 ------------------------
21275 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
21276 function Process (N : Node_Id) return Traverse_Result;
21282 function Process (N : Node_Id) return Traverse_Result is
21286 if Nkind (N) = N_Discriminant_Specification then
21287 Comp := First_Discriminant (Typ);
21288 while Present (Comp) loop
21289 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21290 Set_Defining_Identifier (N, Comp);
21294 Next_Discriminant (Comp);
21297 elsif Nkind (N) = N_Component_Declaration then
21298 Comp := First_Component (Typ);
21299 while Present (Comp) loop
21300 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21301 Set_Defining_Identifier (N, Comp);
21305 Next_Component (Comp);
21312 procedure Replace is new Traverse_Proc (Process);
21314 -- Start of processing for Replace_Components
21318 end Replace_Components;
21320 -------------------------------
21321 -- Set_Completion_Referenced --
21322 -------------------------------
21324 procedure Set_Completion_Referenced (E : Entity_Id) is
21326 -- If in main unit, mark entity that is a completion as referenced,
21327 -- warnings go on the partial view when needed.
21329 if In_Extended_Main_Source_Unit (E) then
21330 Set_Referenced (E);
21332 end Set_Completion_Referenced;
21334 ---------------------
21335 -- Set_Default_SSO --
21336 ---------------------
21338 procedure Set_Default_SSO (T : Entity_Id) is
21340 case Opt.Default_SSO is
21344 Set_SSO_Set_Low_By_Default (T, True);
21346 Set_SSO_Set_High_By_Default (T, True);
21348 raise Program_Error;
21350 end Set_Default_SSO;
21352 ---------------------
21353 -- Set_Fixed_Range --
21354 ---------------------
21356 -- The range for fixed-point types is complicated by the fact that we
21357 -- do not know the exact end points at the time of the declaration. This
21358 -- is true for three reasons:
21360 -- A size clause may affect the fudging of the end-points.
21361 -- A small clause may affect the values of the end-points.
21362 -- We try to include the end-points if it does not affect the size.
21364 -- This means that the actual end-points must be established at the
21365 -- point when the type is frozen. Meanwhile, we first narrow the range
21366 -- as permitted (so that it will fit if necessary in a small specified
21367 -- size), and then build a range subtree with these narrowed bounds.
21368 -- Set_Fixed_Range constructs the range from real literal values, and
21369 -- sets the range as the Scalar_Range of the given fixed-point type entity.
21371 -- The parent of this range is set to point to the entity so that it is
21372 -- properly hooked into the tree (unlike normal Scalar_Range entries for
21373 -- other scalar types, which are just pointers to the range in the
21374 -- original tree, this would otherwise be an orphan).
21376 -- The tree is left unanalyzed. When the type is frozen, the processing
21377 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
21378 -- analyzed, and uses this as an indication that it should complete
21379 -- work on the range (it will know the final small and size values).
21381 procedure Set_Fixed_Range
21387 S : constant Node_Id :=
21389 Low_Bound => Make_Real_Literal (Loc, Lo),
21390 High_Bound => Make_Real_Literal (Loc, Hi));
21392 Set_Scalar_Range (E, S);
21395 -- Before the freeze point, the bounds of a fixed point are universal
21396 -- and carry the corresponding type.
21398 Set_Etype (Low_Bound (S), Universal_Real);
21399 Set_Etype (High_Bound (S), Universal_Real);
21400 end Set_Fixed_Range;
21402 ----------------------------------
21403 -- Set_Scalar_Range_For_Subtype --
21404 ----------------------------------
21406 procedure Set_Scalar_Range_For_Subtype
21407 (Def_Id : Entity_Id;
21411 Kind : constant Entity_Kind := Ekind (Def_Id);
21414 -- Defend against previous error
21416 if Nkind (R) = N_Error then
21420 Set_Scalar_Range (Def_Id, R);
21422 -- We need to link the range into the tree before resolving it so
21423 -- that types that are referenced, including importantly the subtype
21424 -- itself, are properly frozen (Freeze_Expression requires that the
21425 -- expression be properly linked into the tree). Of course if it is
21426 -- already linked in, then we do not disturb the current link.
21428 if No (Parent (R)) then
21429 Set_Parent (R, Def_Id);
21432 -- Reset the kind of the subtype during analysis of the range, to
21433 -- catch possible premature use in the bounds themselves.
21435 Set_Ekind (Def_Id, E_Void);
21436 Process_Range_Expr_In_Decl (R, Subt, Subtyp => Def_Id);
21437 Set_Ekind (Def_Id, Kind);
21438 end Set_Scalar_Range_For_Subtype;
21440 --------------------------------------------------------
21441 -- Set_Stored_Constraint_From_Discriminant_Constraint --
21442 --------------------------------------------------------
21444 procedure Set_Stored_Constraint_From_Discriminant_Constraint
21448 -- Make sure set if encountered during Expand_To_Stored_Constraint
21450 Set_Stored_Constraint (E, No_Elist);
21452 -- Give it the right value
21454 if Is_Constrained (E) and then Has_Discriminants (E) then
21455 Set_Stored_Constraint (E,
21456 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
21458 end Set_Stored_Constraint_From_Discriminant_Constraint;
21460 -------------------------------------
21461 -- Signed_Integer_Type_Declaration --
21462 -------------------------------------
21464 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
21465 Implicit_Base : Entity_Id;
21466 Base_Typ : Entity_Id;
21469 Errs : Boolean := False;
21473 function Can_Derive_From (E : Entity_Id) return Boolean;
21474 -- Determine whether given bounds allow derivation from specified type
21476 procedure Check_Bound (Expr : Node_Id);
21477 -- Check bound to make sure it is integral and static. If not, post
21478 -- appropriate error message and set Errs flag
21480 ---------------------
21481 -- Can_Derive_From --
21482 ---------------------
21484 -- Note we check both bounds against both end values, to deal with
21485 -- strange types like ones with a range of 0 .. -12341234.
21487 function Can_Derive_From (E : Entity_Id) return Boolean is
21488 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
21489 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
21491 return Lo <= Lo_Val and then Lo_Val <= Hi
21493 Lo <= Hi_Val and then Hi_Val <= Hi;
21494 end Can_Derive_From;
21500 procedure Check_Bound (Expr : Node_Id) is
21502 -- If a range constraint is used as an integer type definition, each
21503 -- bound of the range must be defined by a static expression of some
21504 -- integer type, but the two bounds need not have the same integer
21505 -- type (Negative bounds are allowed.) (RM 3.5.4)
21507 if not Is_Integer_Type (Etype (Expr)) then
21509 ("integer type definition bounds must be of integer type", Expr);
21512 elsif not Is_OK_Static_Expression (Expr) then
21513 Flag_Non_Static_Expr
21514 ("non-static expression used for integer type bound!", Expr);
21517 -- The bounds are folded into literals, and we set their type to be
21518 -- universal, to avoid typing difficulties: we cannot set the type
21519 -- of the literal to the new type, because this would be a forward
21520 -- reference for the back end, and if the original type is user-
21521 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
21524 if Is_Entity_Name (Expr) then
21525 Fold_Uint (Expr, Expr_Value (Expr), True);
21528 Set_Etype (Expr, Universal_Integer);
21532 -- Start of processing for Signed_Integer_Type_Declaration
21535 -- Create an anonymous base type
21538 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
21540 -- Analyze and check the bounds, they can be of any integer type
21542 Lo := Low_Bound (Def);
21543 Hi := High_Bound (Def);
21545 -- Arbitrarily use Integer as the type if either bound had an error
21547 if Hi = Error or else Lo = Error then
21548 Base_Typ := Any_Integer;
21549 Set_Error_Posted (T, True);
21551 -- Here both bounds are OK expressions
21554 Analyze_And_Resolve (Lo, Any_Integer);
21555 Analyze_And_Resolve (Hi, Any_Integer);
21561 Hi := Type_High_Bound (Standard_Long_Long_Integer);
21562 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
21565 -- Find type to derive from
21567 Lo_Val := Expr_Value (Lo);
21568 Hi_Val := Expr_Value (Hi);
21570 if Can_Derive_From (Standard_Short_Short_Integer) then
21571 Base_Typ := Base_Type (Standard_Short_Short_Integer);
21573 elsif Can_Derive_From (Standard_Short_Integer) then
21574 Base_Typ := Base_Type (Standard_Short_Integer);
21576 elsif Can_Derive_From (Standard_Integer) then
21577 Base_Typ := Base_Type (Standard_Integer);
21579 elsif Can_Derive_From (Standard_Long_Integer) then
21580 Base_Typ := Base_Type (Standard_Long_Integer);
21582 elsif Can_Derive_From (Standard_Long_Long_Integer) then
21583 Check_Restriction (No_Long_Long_Integers, Def);
21584 Base_Typ := Base_Type (Standard_Long_Long_Integer);
21587 Base_Typ := Base_Type (Standard_Long_Long_Integer);
21588 Error_Msg_N ("integer type definition bounds out of range", Def);
21589 Hi := Type_High_Bound (Standard_Long_Long_Integer);
21590 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
21594 -- Complete both implicit base and declared first subtype entities. The
21595 -- inheritance of the rep item chain ensures that SPARK-related pragmas
21596 -- are not clobbered when the signed integer type acts as a full view of
21599 Set_Etype (Implicit_Base, Base_Typ);
21600 Set_Size_Info (Implicit_Base, Base_Typ);
21601 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
21602 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
21603 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
21605 Set_Ekind (T, E_Signed_Integer_Subtype);
21606 Set_Etype (T, Implicit_Base);
21607 Set_Size_Info (T, Implicit_Base);
21608 Inherit_Rep_Item_Chain (T, Implicit_Base);
21609 Set_Scalar_Range (T, Def);
21610 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
21611 Set_Is_Constrained (T);
21612 end Signed_Integer_Type_Declaration;