1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2011, 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 Atree; use Atree;
27 with Checks; use Checks;
28 with Debug; use Debug;
29 with Elists; use Elists;
30 with Einfo; use Einfo;
31 with Errout; use Errout;
32 with Eval_Fat; use Eval_Fat;
33 with Exp_Ch3; use Exp_Ch3;
34 with Exp_Ch9; use Exp_Ch9;
35 with Exp_Disp; use Exp_Disp;
36 with Exp_Dist; use Exp_Dist;
37 with Exp_Tss; use Exp_Tss;
38 with Exp_Util; use Exp_Util;
39 with Fname; use Fname;
40 with Freeze; use Freeze;
41 with Itypes; use Itypes;
42 with Layout; use Layout;
44 with Lib.Xref; use Lib.Xref;
45 with Namet; use Namet;
46 with Nmake; use Nmake;
48 with Restrict; use Restrict;
49 with Rident; use Rident;
50 with Rtsfind; use Rtsfind;
52 with Sem_Aux; use Sem_Aux;
53 with Sem_Case; use Sem_Case;
54 with Sem_Cat; use Sem_Cat;
55 with Sem_Ch6; use Sem_Ch6;
56 with Sem_Ch7; use Sem_Ch7;
57 with Sem_Ch8; use Sem_Ch8;
58 with Sem_Ch13; use Sem_Ch13;
59 with Sem_Disp; use Sem_Disp;
60 with Sem_Dist; use Sem_Dist;
61 with Sem_Elim; use Sem_Elim;
62 with Sem_Eval; use Sem_Eval;
63 with Sem_Mech; use Sem_Mech;
64 with Sem_Prag; use Sem_Prag;
65 with Sem_Res; use Sem_Res;
66 with Sem_Smem; use Sem_Smem;
67 with Sem_Type; use Sem_Type;
68 with Sem_Util; use Sem_Util;
69 with Sem_Warn; use Sem_Warn;
70 with Stand; use Stand;
71 with Sinfo; use Sinfo;
72 with Sinput; use Sinput;
73 with Snames; use Snames;
74 with Targparm; use Targparm;
75 with Tbuild; use Tbuild;
76 with Ttypes; use Ttypes;
77 with Uintp; use Uintp;
78 with Urealp; use Urealp;
80 package body Sem_Ch3 is
82 -----------------------
83 -- Local Subprograms --
84 -----------------------
86 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id);
87 -- Ada 2005 (AI-251): Add the tag components corresponding to all the
88 -- abstract interface types implemented by a record type or a derived
91 procedure Build_Derived_Type
93 Parent_Type : Entity_Id;
94 Derived_Type : Entity_Id;
95 Is_Completion : Boolean;
96 Derive_Subps : Boolean := True);
97 -- Create and decorate a Derived_Type given the Parent_Type entity. N is
98 -- the N_Full_Type_Declaration node containing the derived type definition.
99 -- Parent_Type is the entity for the parent type in the derived type
100 -- definition and Derived_Type the actual derived type. Is_Completion must
101 -- be set to False if Derived_Type is the N_Defining_Identifier node in N
102 -- (i.e. Derived_Type = Defining_Identifier (N)). In this case N is not the
103 -- completion of a private type declaration. If Is_Completion is set to
104 -- True, N is the completion of a private type declaration and Derived_Type
105 -- is different from the defining identifier inside N (i.e. Derived_Type /=
106 -- Defining_Identifier (N)). Derive_Subps indicates whether the parent
107 -- subprograms should be derived. The only case where this parameter is
108 -- False is when Build_Derived_Type is recursively called to process an
109 -- implicit derived full type for a type derived from a private type (in
110 -- that case the subprograms must only be derived for the private view of
113 -- ??? These flags need a bit of re-examination and re-documentation:
114 -- ??? are they both necessary (both seem related to the recursion)?
116 procedure Build_Derived_Access_Type
118 Parent_Type : Entity_Id;
119 Derived_Type : Entity_Id);
120 -- Subsidiary procedure to Build_Derived_Type. For a derived access type,
121 -- create an implicit base if the parent type is constrained or if the
122 -- subtype indication has a constraint.
124 procedure Build_Derived_Array_Type
126 Parent_Type : Entity_Id;
127 Derived_Type : Entity_Id);
128 -- Subsidiary procedure to Build_Derived_Type. For a derived array type,
129 -- create an implicit base if the parent type is constrained or if the
130 -- subtype indication has a constraint.
132 procedure Build_Derived_Concurrent_Type
134 Parent_Type : Entity_Id;
135 Derived_Type : Entity_Id);
136 -- Subsidiary procedure to Build_Derived_Type. For a derived task or
137 -- protected type, inherit entries and protected subprograms, check
138 -- legality of discriminant constraints if any.
140 procedure Build_Derived_Enumeration_Type
142 Parent_Type : Entity_Id;
143 Derived_Type : Entity_Id);
144 -- Subsidiary procedure to Build_Derived_Type. For a derived enumeration
145 -- type, we must create a new list of literals. Types derived from
146 -- Character and [Wide_]Wide_Character are special-cased.
148 procedure Build_Derived_Numeric_Type
150 Parent_Type : Entity_Id;
151 Derived_Type : Entity_Id);
152 -- Subsidiary procedure to Build_Derived_Type. For numeric types, create
153 -- an anonymous base type, and propagate constraint to subtype if needed.
155 procedure Build_Derived_Private_Type
157 Parent_Type : Entity_Id;
158 Derived_Type : Entity_Id;
159 Is_Completion : Boolean;
160 Derive_Subps : Boolean := True);
161 -- Subsidiary procedure to Build_Derived_Type. This procedure is complex
162 -- because the parent may or may not have a completion, and the derivation
163 -- may itself be a completion.
165 procedure Build_Derived_Record_Type
167 Parent_Type : Entity_Id;
168 Derived_Type : Entity_Id;
169 Derive_Subps : Boolean := True);
170 -- Subsidiary procedure for Build_Derived_Type and
171 -- Analyze_Private_Extension_Declaration used for tagged and untagged
172 -- record types. All parameters are as in Build_Derived_Type except that
173 -- N, in addition to being an N_Full_Type_Declaration node, can also be an
174 -- N_Private_Extension_Declaration node. See the definition of this routine
175 -- for much more info. Derive_Subps indicates whether subprograms should
176 -- be derived from the parent type. The only case where Derive_Subps is
177 -- False is for an implicit derived full type for a type derived from a
178 -- private type (see Build_Derived_Type).
180 procedure Build_Discriminal (Discrim : Entity_Id);
181 -- Create the discriminal corresponding to discriminant Discrim, that is
182 -- the parameter corresponding to Discrim to be used in initialization
183 -- procedures for the type where Discrim is a discriminant. Discriminals
184 -- are not used during semantic analysis, and are not fully defined
185 -- entities until expansion. Thus they are not given a scope until
186 -- initialization procedures are built.
188 function Build_Discriminant_Constraints
191 Derived_Def : Boolean := False) return Elist_Id;
192 -- Validate discriminant constraints and return the list of the constraints
193 -- in order of discriminant declarations, where T is the discriminated
194 -- unconstrained type. Def is the N_Subtype_Indication node where the
195 -- discriminants constraints for T are specified. Derived_Def is True
196 -- when building the discriminant constraints in a derived type definition
197 -- of the form "type D (...) is new T (xxx)". In this case T is the parent
198 -- type and Def is the constraint "(xxx)" on T and this routine sets the
199 -- Corresponding_Discriminant field of the discriminants in the derived
200 -- type D to point to the corresponding discriminants in the parent type T.
202 procedure Build_Discriminated_Subtype
206 Related_Nod : Node_Id;
207 For_Access : Boolean := False);
208 -- Subsidiary procedure to Constrain_Discriminated_Type and to
209 -- Process_Incomplete_Dependents. Given
211 -- T (a possibly discriminated base type)
212 -- Def_Id (a very partially built subtype for T),
214 -- the call completes Def_Id to be the appropriate E_*_Subtype.
216 -- The Elist is the list of discriminant constraints if any (it is set
217 -- to No_Elist if T is not a discriminated type, and to an empty list if
218 -- T has discriminants but there are no discriminant constraints). The
219 -- Related_Nod is the same as Decl_Node in Create_Constrained_Components.
220 -- The For_Access says whether or not this subtype is really constraining
221 -- an access type. That is its sole purpose is the designated type of an
222 -- access type -- in which case a Private_Subtype Is_For_Access_Subtype
223 -- is built to avoid freezing T when the access subtype is frozen.
225 function Build_Scalar_Bound
228 Der_T : Entity_Id) return Node_Id;
229 -- The bounds of a derived scalar type are conversions of the bounds of
230 -- the parent type. Optimize the representation if the bounds are literals.
231 -- Needs a more complete spec--what are the parameters exactly, and what
232 -- exactly is the returned value, and how is Bound affected???
234 procedure Build_Underlying_Full_View
238 -- If the completion of a private type is itself derived from a private
239 -- type, or if the full view of a private subtype is itself private, the
240 -- back-end has no way to compute the actual size of this type. We build
241 -- an internal subtype declaration of the proper parent type to convey
242 -- this information. This extra mechanism is needed because a full
243 -- view cannot itself have a full view (it would get clobbered during
246 procedure Check_Access_Discriminant_Requires_Limited
249 -- Check the restriction that the type to which an access discriminant
250 -- belongs must be a concurrent type or a descendant of a type with
251 -- the reserved word 'limited' in its declaration.
253 procedure Check_Anonymous_Access_Components
257 Comp_List : Node_Id);
258 -- Ada 2005 AI-382: an access component in a record definition can refer to
259 -- the enclosing record, in which case it denotes the type itself, and not
260 -- the current instance of the type. We create an anonymous access type for
261 -- the component, and flag it as an access to a component, so accessibility
262 -- checks are properly performed on it. The declaration of the access type
263 -- is placed ahead of that of the record to prevent order-of-elaboration
264 -- circularity issues in Gigi. We create an incomplete type for the record
265 -- declaration, which is the designated type of the anonymous access.
267 procedure Check_Delta_Expression (E : Node_Id);
268 -- Check that the expression represented by E is suitable for use as a
269 -- delta expression, i.e. it is of real type and is static.
271 procedure Check_Digits_Expression (E : Node_Id);
272 -- Check that the expression represented by E is suitable for use as a
273 -- digits expression, i.e. it is of integer type, positive and static.
275 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id);
276 -- Validate the initialization of an object declaration. T is the required
277 -- type, and Exp is the initialization expression.
279 procedure Check_Interfaces (N : Node_Id; Def : Node_Id);
280 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
282 procedure Check_Or_Process_Discriminants
285 Prev : Entity_Id := Empty);
286 -- If N is the full declaration of the completion T of an incomplete or
287 -- private type, check its discriminants (which are already known to be
288 -- conformant with those of the partial view, see Find_Type_Name),
289 -- otherwise process them. Prev is the entity of the partial declaration,
292 procedure Check_Real_Bound (Bound : Node_Id);
293 -- Check given bound for being of real type and static. If not, post an
294 -- appropriate message, and rewrite the bound with the real literal zero.
296 procedure Constant_Redeclaration
300 -- Various checks on legality of full declaration of deferred constant.
301 -- Id is the entity for the redeclaration, N is the N_Object_Declaration,
302 -- node. The caller has not yet set any attributes of this entity.
304 function Contain_Interface
306 Ifaces : Elist_Id) return Boolean;
307 -- Ada 2005: Determine whether Iface is present in the list Ifaces
309 procedure Convert_Scalar_Bounds
311 Parent_Type : Entity_Id;
312 Derived_Type : Entity_Id;
314 -- For derived scalar types, convert the bounds in the type definition to
315 -- the derived type, and complete their analysis. Given a constraint of the
316 -- form ".. new T range Lo .. Hi", Lo and Hi are analyzed and resolved with
317 -- T'Base, the parent_type. The bounds of the derived type (the anonymous
318 -- base) are copies of Lo and Hi. Finally, the bounds of the derived
319 -- subtype are conversions of those bounds to the derived_type, so that
320 -- their typing is consistent.
322 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id);
323 -- Copies attributes from array base type T2 to array base type T1. Copies
324 -- only attributes that apply to base types, but not subtypes.
326 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id);
327 -- Copies attributes from array subtype T2 to array subtype T1. Copies
328 -- attributes that apply to both subtypes and base types.
330 procedure Create_Constrained_Components
334 Constraints : Elist_Id);
335 -- Build the list of entities for a constrained discriminated record
336 -- subtype. If a component depends on a discriminant, replace its subtype
337 -- using the discriminant values in the discriminant constraint. Subt
338 -- is the defining identifier for the subtype whose list of constrained
339 -- entities we will create. Decl_Node is the type declaration node where
340 -- we will attach all the itypes created. Typ is the base discriminated
341 -- type for the subtype Subt. Constraints is the list of discriminant
342 -- constraints for Typ.
344 function Constrain_Component_Type
346 Constrained_Typ : Entity_Id;
347 Related_Node : Node_Id;
349 Constraints : Elist_Id) return Entity_Id;
350 -- Given a discriminated base type Typ, a list of discriminant constraint
351 -- Constraints for Typ and a component of Typ, with type Compon_Type,
352 -- create and return the type corresponding to Compon_type where all
353 -- discriminant references are replaced with the corresponding constraint.
354 -- If no discriminant references occur in Compon_Typ then return it as is.
355 -- Constrained_Typ is the final constrained subtype to which the
356 -- constrained Compon_Type belongs. Related_Node is the node where we will
357 -- attach all the itypes created.
359 -- Above description is confused, what is Compon_Type???
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;
413 Related_Id : Entity_Id) return Entity_Id;
414 -- When constraining a protected type or task type with discriminants,
415 -- constrain the corresponding record with the same discriminant values.
417 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id);
418 -- Constrain a decimal fixed point type with a digits constraint and/or a
419 -- range constraint, and build E_Decimal_Fixed_Point_Subtype entity.
421 procedure Constrain_Discriminated_Type
424 Related_Nod : Node_Id;
425 For_Access : Boolean := False);
426 -- Process discriminant constraints of composite type. Verify that values
427 -- have been provided for all discriminants, that the original type is
428 -- unconstrained, and that the types of the supplied expressions match
429 -- the discriminant types. The first three parameters are like in routine
430 -- Constrain_Concurrent. See Build_Discriminated_Subtype for an explanation
433 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id);
434 -- Constrain an enumeration type with a range constraint. This is identical
435 -- to Constrain_Integer, but for the Ekind of the resulting subtype.
437 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id);
438 -- Constrain a floating point type with either a digits constraint
439 -- and/or a range constraint, building a E_Floating_Point_Subtype.
441 procedure Constrain_Index
444 Related_Nod : Node_Id;
445 Related_Id : Entity_Id;
448 -- Process an index constraint S in a constrained array declaration. The
449 -- constraint can be a subtype name, or a range with or without an explicit
450 -- subtype mark. The index is the corresponding index of the unconstrained
451 -- array. The Related_Id and Suffix parameters are used to build the
452 -- associated Implicit type name.
454 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id);
455 -- Build subtype of a signed or modular integer type
457 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id);
458 -- Constrain an ordinary fixed point type with a range constraint, and
459 -- build an E_Ordinary_Fixed_Point_Subtype entity.
461 procedure Copy_And_Swap (Priv, Full : Entity_Id);
462 -- Copy the Priv entity into the entity of its full declaration then swap
463 -- the two entities in such a manner that the former private type is now
464 -- seen as a full type.
466 procedure Decimal_Fixed_Point_Type_Declaration
469 -- Create a new decimal fixed point type, and apply the constraint to
470 -- obtain a subtype of this new type.
472 procedure Complete_Private_Subtype
475 Full_Base : Entity_Id;
476 Related_Nod : Node_Id);
477 -- Complete the implicit full view of a private subtype by setting the
478 -- appropriate semantic fields. If the full view of the parent is a record
479 -- type, build constrained components of subtype.
481 procedure Derive_Progenitor_Subprograms
482 (Parent_Type : Entity_Id;
483 Tagged_Type : Entity_Id);
484 -- Ada 2005 (AI-251): To complete type derivation, collect the primitive
485 -- operations of progenitors of Tagged_Type, and replace the subsidiary
486 -- subtypes with Tagged_Type, to build the specs of the inherited interface
487 -- primitives. The derived primitives are aliased to those of the
488 -- interface. This routine takes care also of transferring to the full view
489 -- subprograms associated with the partial view of Tagged_Type that cover
490 -- interface primitives.
492 procedure Derived_Standard_Character
494 Parent_Type : Entity_Id;
495 Derived_Type : Entity_Id);
496 -- Subsidiary procedure to Build_Derived_Enumeration_Type which handles
497 -- derivations from types Standard.Character and Standard.Wide_Character.
499 procedure Derived_Type_Declaration
502 Is_Completion : Boolean);
503 -- Process a derived type declaration. Build_Derived_Type is invoked
504 -- to process the actual derived type definition. Parameters N and
505 -- Is_Completion have the same meaning as in Build_Derived_Type.
506 -- T is the N_Defining_Identifier for the entity defined in the
507 -- N_Full_Type_Declaration node N, that is T is the derived type.
509 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id);
510 -- Insert each literal in symbol table, as an overloadable identifier. Each
511 -- enumeration type is mapped into a sequence of integers, and each literal
512 -- is defined as a constant with integer value. If any of the literals are
513 -- character literals, the type is a character type, which means that
514 -- strings are legal aggregates for arrays of components of the type.
516 function Expand_To_Stored_Constraint
518 Constraint : Elist_Id) return Elist_Id;
519 -- Given a constraint (i.e. a list of expressions) on the discriminants of
520 -- Typ, expand it into a constraint on the stored discriminants and return
521 -- the new list of expressions constraining the stored discriminants.
523 function Find_Type_Of_Object
525 Related_Nod : Node_Id) return Entity_Id;
526 -- Get type entity for object referenced by Obj_Def, attaching the
527 -- implicit types generated to Related_Nod
529 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id);
530 -- Create a new float and apply the constraint to obtain subtype of it
532 function Has_Range_Constraint (N : Node_Id) return Boolean;
533 -- Given an N_Subtype_Indication node N, return True if a range constraint
534 -- is present, either directly, or as part of a digits or delta constraint.
535 -- In addition, a digits constraint in the decimal case returns True, since
536 -- it establishes a default range if no explicit range is present.
538 function Inherit_Components
540 Parent_Base : Entity_Id;
541 Derived_Base : Entity_Id;
543 Inherit_Discr : Boolean;
544 Discs : Elist_Id) return Elist_Id;
545 -- Called from Build_Derived_Record_Type to inherit the components of
546 -- Parent_Base (a base type) into the Derived_Base (the derived base type).
547 -- For more information on derived types and component inheritance please
548 -- consult the comment above the body of Build_Derived_Record_Type.
550 -- N is the original derived type declaration
552 -- Is_Tagged is set if we are dealing with tagged types
554 -- If Inherit_Discr is set, Derived_Base inherits its discriminants from
555 -- Parent_Base, otherwise no discriminants are inherited.
557 -- Discs gives the list of constraints that apply to Parent_Base in the
558 -- derived type declaration. If Discs is set to No_Elist, then we have
559 -- the following situation:
561 -- type Parent (D1..Dn : ..) is [tagged] record ...;
562 -- type Derived is new Parent [with ...];
564 -- which gets treated as
566 -- type Derived (D1..Dn : ..) is new Parent (D1,..,Dn) [with ...];
568 -- For untagged types the returned value is an association list. The list
569 -- starts from the association (Parent_Base => Derived_Base), and then it
570 -- contains a sequence of the associations of the form
572 -- (Old_Component => New_Component),
574 -- where Old_Component is the Entity_Id of a component in Parent_Base and
575 -- New_Component is the Entity_Id of the corresponding component in
576 -- Derived_Base. For untagged records, this association list is needed when
577 -- copying the record declaration for the derived base. In the tagged case
578 -- the value returned is irrelevant.
580 function Is_Valid_Constraint_Kind
582 Constraint_Kind : Node_Kind) return Boolean;
583 -- Returns True if it is legal to apply the given kind of constraint to the
584 -- given kind of type (index constraint to an array type, for example).
586 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id);
587 -- Create new modular type. Verify that modulus is in bounds
589 procedure New_Concatenation_Op (Typ : Entity_Id);
590 -- Create an abbreviated declaration for an operator in order to
591 -- materialize concatenation on array types.
593 procedure Ordinary_Fixed_Point_Type_Declaration
596 -- Create a new ordinary fixed point type, and apply the constraint to
597 -- obtain subtype of it.
599 procedure Prepare_Private_Subtype_Completion
601 Related_Nod : Node_Id);
602 -- Id is a subtype of some private type. Creates the full declaration
603 -- associated with Id whenever possible, i.e. when the full declaration
604 -- of the base type is already known. Records each subtype into
605 -- Private_Dependents of the base type.
607 procedure Process_Incomplete_Dependents
611 -- Process all entities that depend on an incomplete type. There include
612 -- subtypes, subprogram types that mention the incomplete type in their
613 -- profiles, and subprogram with access parameters that designate the
616 -- Inc_T is the defining identifier of an incomplete type declaration, its
617 -- Ekind is E_Incomplete_Type.
619 -- N is the corresponding N_Full_Type_Declaration for Inc_T.
621 -- Full_T is N's defining identifier.
623 -- Subtypes of incomplete types with discriminants are completed when the
624 -- parent type is. This is simpler than private subtypes, because they can
625 -- only appear in the same scope, and there is no need to exchange views.
626 -- Similarly, access_to_subprogram types may have a parameter or a return
627 -- type that is an incomplete type, and that must be replaced with the
630 -- If the full type is tagged, subprogram with access parameters that
631 -- designated the incomplete may be primitive operations of the full type,
632 -- and have to be processed accordingly.
634 procedure Process_Real_Range_Specification (Def : Node_Id);
635 -- Given the type definition for a real type, this procedure processes and
636 -- checks the real range specification of this type definition if one is
637 -- present. If errors are found, error messages are posted, and the
638 -- Real_Range_Specification of Def is reset to Empty.
640 procedure Record_Type_Declaration
644 -- Process a record type declaration (for both untagged and tagged
645 -- records). Parameters T and N are exactly like in procedure
646 -- Derived_Type_Declaration, except that no flag Is_Completion is needed
647 -- for this routine. If this is the completion of an incomplete type
648 -- declaration, Prev is the entity of the incomplete declaration, used for
649 -- cross-referencing. Otherwise Prev = T.
651 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id);
652 -- This routine is used to process the actual record type definition (both
653 -- for untagged and tagged records). Def is a record type definition node.
654 -- This procedure analyzes the components in this record type definition.
655 -- Prev_T is the entity for the enclosing record type. It is provided so
656 -- that its Has_Task flag can be set if any of the component have Has_Task
657 -- set. If the declaration is the completion of an incomplete type
658 -- declaration, Prev_T is the original incomplete type, whose full view is
661 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id);
662 -- Subsidiary to Build_Derived_Record_Type. For untagged records, we
663 -- build a copy of the declaration tree of the parent, and we create
664 -- independently the list of components for the derived type. Semantic
665 -- information uses the component entities, but record representation
666 -- clauses are validated on the declaration tree. This procedure replaces
667 -- discriminants and components in the declaration with those that have
668 -- been created by Inherit_Components.
670 procedure Set_Fixed_Range
675 -- Build a range node with the given bounds and set it as the Scalar_Range
676 -- of the given fixed-point type entity. Loc is the source location used
677 -- for the constructed range. See body for further details.
679 procedure Set_Scalar_Range_For_Subtype
683 -- This routine is used to set the scalar range field for a subtype given
684 -- Def_Id, the entity for the subtype, and R, the range expression for the
685 -- scalar range. Subt provides the parent subtype to be used to analyze,
686 -- resolve, and check the given range.
688 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id);
689 -- Create a new signed integer entity, and apply the constraint to obtain
690 -- the required first named subtype of this type.
692 procedure Set_Stored_Constraint_From_Discriminant_Constraint
694 -- E is some record type. This routine computes E's Stored_Constraint
695 -- from its Discriminant_Constraint.
697 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id);
698 -- Check that an entity in a list of progenitors is an interface,
699 -- emit error otherwise.
701 -----------------------
702 -- Access_Definition --
703 -----------------------
705 function Access_Definition
706 (Related_Nod : Node_Id;
707 N : Node_Id) return Entity_Id
709 Loc : constant Source_Ptr := Sloc (Related_Nod);
710 Anon_Type : Entity_Id;
711 Anon_Scope : Entity_Id;
712 Desig_Type : Entity_Id;
714 Enclosing_Prot_Type : Entity_Id := Empty;
717 Check_SPARK_Restriction ("access type is not allowed", N);
719 if Is_Entry (Current_Scope)
720 and then Is_Task_Type (Etype (Scope (Current_Scope)))
722 Error_Msg_N ("task entries cannot have access parameters", N);
726 -- Ada 2005: for an object declaration the corresponding anonymous
727 -- type is declared in the current scope.
729 -- If the access definition is the return type of another access to
730 -- function, scope is the current one, because it is the one of the
731 -- current type declaration.
733 if Nkind_In (Related_Nod, N_Object_Declaration,
734 N_Access_Function_Definition)
736 Anon_Scope := Current_Scope;
738 -- For the anonymous function result case, retrieve the scope of the
739 -- function specification's associated entity rather than using the
740 -- current scope. The current scope will be the function itself if the
741 -- formal part is currently being analyzed, but will be the parent scope
742 -- in the case of a parameterless function, and we always want to use
743 -- the function's parent scope. Finally, if the function is a child
744 -- unit, we must traverse the tree to retrieve the proper entity.
746 elsif Nkind (Related_Nod) = N_Function_Specification
747 and then Nkind (Parent (N)) /= N_Parameter_Specification
749 -- If the current scope is a protected type, the anonymous access
750 -- is associated with one of the protected operations, and must
751 -- be available in the scope that encloses the protected declaration.
752 -- Otherwise the type is in the scope enclosing the subprogram.
754 -- If the function has formals, The return type of a subprogram
755 -- declaration is analyzed in the scope of the subprogram (see
756 -- Process_Formals) and thus the protected type, if present, is
757 -- the scope of the current function scope.
759 if Ekind (Current_Scope) = E_Protected_Type then
760 Enclosing_Prot_Type := Current_Scope;
762 elsif Ekind (Current_Scope) = E_Function
763 and then Ekind (Scope (Current_Scope)) = E_Protected_Type
765 Enclosing_Prot_Type := Scope (Current_Scope);
768 if Present (Enclosing_Prot_Type) then
769 Anon_Scope := Scope (Enclosing_Prot_Type);
772 Anon_Scope := Scope (Defining_Entity (Related_Nod));
776 -- For access formals, access components, and access discriminants,
777 -- the scope is that of the enclosing declaration,
779 Anon_Scope := Scope (Current_Scope);
784 (E_Anonymous_Access_Type, Related_Nod, Scope_Id => Anon_Scope);
787 and then Ada_Version >= Ada_2005
789 Error_Msg_N ("ALL is not permitted for anonymous access types", N);
792 -- Ada 2005 (AI-254): In case of anonymous access to subprograms call
793 -- the corresponding semantic routine
795 if Present (Access_To_Subprogram_Definition (N)) then
796 Access_Subprogram_Declaration
797 (T_Name => Anon_Type,
798 T_Def => Access_To_Subprogram_Definition (N));
800 if Ekind (Anon_Type) = E_Access_Protected_Subprogram_Type then
802 (Anon_Type, E_Anonymous_Access_Protected_Subprogram_Type);
805 (Anon_Type, E_Anonymous_Access_Subprogram_Type);
808 Set_Can_Use_Internal_Rep
809 (Anon_Type, not Always_Compatible_Rep_On_Target);
811 -- If the anonymous access is associated with a protected operation
812 -- create a reference to it after the enclosing protected definition
813 -- because the itype will be used in the subsequent bodies.
815 if Ekind (Current_Scope) = E_Protected_Type then
816 Build_Itype_Reference (Anon_Type, Parent (Current_Scope));
822 Find_Type (Subtype_Mark (N));
823 Desig_Type := Entity (Subtype_Mark (N));
825 Set_Directly_Designated_Type (Anon_Type, Desig_Type);
826 Set_Etype (Anon_Type, Anon_Type);
828 -- Make sure the anonymous access type has size and alignment fields
829 -- set, as required by gigi. This is necessary in the case of the
830 -- Task_Body_Procedure.
832 if not Has_Private_Component (Desig_Type) then
833 Layout_Type (Anon_Type);
836 -- Ada 2005 (AI-231): Ada 2005 semantics for anonymous access differs
837 -- from Ada 95 semantics. In Ada 2005, anonymous access must specify if
838 -- the null value is allowed. In Ada 95 the null value is never allowed.
840 if Ada_Version >= Ada_2005 then
841 Set_Can_Never_Be_Null (Anon_Type, Null_Exclusion_Present (N));
843 Set_Can_Never_Be_Null (Anon_Type, True);
846 -- The anonymous access type is as public as the discriminated type or
847 -- subprogram that defines it. It is imported (for back-end purposes)
848 -- if the designated type is.
850 Set_Is_Public (Anon_Type, Is_Public (Scope (Anon_Type)));
852 -- Ada 2005 (AI-231): Propagate the access-constant attribute
854 Set_Is_Access_Constant (Anon_Type, Constant_Present (N));
856 -- The context is either a subprogram declaration, object declaration,
857 -- or an access discriminant, in a private or a full type declaration.
858 -- In the case of a subprogram, if the designated type is incomplete,
859 -- the operation will be a primitive operation of the full type, to be
860 -- updated subsequently. If the type is imported through a limited_with
861 -- clause, the subprogram is not a primitive operation of the type
862 -- (which is declared elsewhere in some other scope).
864 if Ekind (Desig_Type) = E_Incomplete_Type
865 and then not From_With_Type (Desig_Type)
866 and then Is_Overloadable (Current_Scope)
868 Append_Elmt (Current_Scope, Private_Dependents (Desig_Type));
869 Set_Has_Delayed_Freeze (Current_Scope);
872 -- Ada 2005: if the designated type is an interface that may contain
873 -- tasks, create a Master entity for the declaration. This must be done
874 -- before expansion of the full declaration, because the declaration may
875 -- include an expression that is an allocator, whose expansion needs the
876 -- proper Master for the created tasks.
878 if Nkind (Related_Nod) = N_Object_Declaration
879 and then Expander_Active
881 if Is_Interface (Desig_Type)
882 and then Is_Limited_Record (Desig_Type)
884 Build_Class_Wide_Master (Anon_Type);
886 -- Similarly, if the type is an anonymous access that designates
887 -- tasks, create a master entity for it in the current context.
889 elsif Has_Task (Desig_Type)
890 and then Comes_From_Source (Related_Nod)
891 and then not Restriction_Active (No_Task_Hierarchy)
893 if not Has_Master_Entity (Current_Scope) then
895 Make_Object_Declaration (Loc,
896 Defining_Identifier =>
897 Make_Defining_Identifier (Loc, Name_uMaster),
898 Constant_Present => True,
900 New_Reference_To (RTE (RE_Master_Id), Loc),
902 Make_Explicit_Dereference (Loc,
903 New_Reference_To (RTE (RE_Current_Master), Loc)));
905 Insert_Before (Related_Nod, Decl);
908 Set_Master_Id (Anon_Type, Defining_Identifier (Decl));
909 Set_Has_Master_Entity (Current_Scope);
911 Build_Master_Renaming (Related_Nod, Anon_Type);
916 -- For a private component of a protected type, it is imperative that
917 -- the back-end elaborate the type immediately after the protected
918 -- declaration, because this type will be used in the declarations
919 -- created for the component within each protected body, so we must
920 -- create an itype reference for it now.
922 if Nkind (Parent (Related_Nod)) = N_Protected_Definition then
923 Build_Itype_Reference (Anon_Type, Parent (Parent (Related_Nod)));
925 -- Similarly, if the access definition is the return result of a
926 -- function, create an itype reference for it because it will be used
927 -- within the function body. For a regular function that is not a
928 -- compilation unit, insert reference after the declaration. For a
929 -- protected operation, insert it after the enclosing protected type
930 -- declaration. In either case, do not create a reference for a type
931 -- obtained through a limited_with clause, because this would introduce
932 -- semantic dependencies.
934 -- Similarly, do not create a reference if the designated type is a
935 -- generic formal, because no use of it will reach the backend.
937 elsif Nkind (Related_Nod) = N_Function_Specification
938 and then not From_With_Type (Desig_Type)
939 and then not Is_Generic_Type (Desig_Type)
941 if Present (Enclosing_Prot_Type) then
942 Build_Itype_Reference (Anon_Type, Parent (Enclosing_Prot_Type));
944 elsif Is_List_Member (Parent (Related_Nod))
945 and then Nkind (Parent (N)) /= N_Parameter_Specification
947 Build_Itype_Reference (Anon_Type, Parent (Related_Nod));
950 -- Finally, create an itype reference for an object declaration of an
951 -- anonymous access type. This is strictly necessary only for deferred
952 -- constants, but in any case will avoid out-of-scope problems in the
955 elsif Nkind (Related_Nod) = N_Object_Declaration then
956 Build_Itype_Reference (Anon_Type, Related_Nod);
960 end Access_Definition;
962 -----------------------------------
963 -- Access_Subprogram_Declaration --
964 -----------------------------------
966 procedure Access_Subprogram_Declaration
971 procedure Check_For_Premature_Usage (Def : Node_Id);
972 -- Check that type T_Name is not used, directly or recursively, as a
973 -- parameter or a return type in Def. Def is either a subtype, an
974 -- access_definition, or an access_to_subprogram_definition.
976 -------------------------------
977 -- Check_For_Premature_Usage --
978 -------------------------------
980 procedure Check_For_Premature_Usage (Def : Node_Id) is
984 -- Check for a subtype mark
986 if Nkind (Def) in N_Has_Etype then
987 if Etype (Def) = T_Name then
989 ("type& cannot be used before end of its declaration", Def);
992 -- If this is not a subtype, then this is an access_definition
994 elsif Nkind (Def) = N_Access_Definition then
995 if Present (Access_To_Subprogram_Definition (Def)) then
996 Check_For_Premature_Usage
997 (Access_To_Subprogram_Definition (Def));
999 Check_For_Premature_Usage (Subtype_Mark (Def));
1002 -- The only cases left are N_Access_Function_Definition and
1003 -- N_Access_Procedure_Definition.
1006 if Present (Parameter_Specifications (Def)) then
1007 Param := First (Parameter_Specifications (Def));
1008 while Present (Param) loop
1009 Check_For_Premature_Usage (Parameter_Type (Param));
1010 Param := Next (Param);
1014 if Nkind (Def) = N_Access_Function_Definition then
1015 Check_For_Premature_Usage (Result_Definition (Def));
1018 end Check_For_Premature_Usage;
1022 Formals : constant List_Id := Parameter_Specifications (T_Def);
1025 Desig_Type : constant Entity_Id :=
1026 Create_Itype (E_Subprogram_Type, Parent (T_Def));
1028 -- Start of processing for Access_Subprogram_Declaration
1031 Check_SPARK_Restriction ("access type is not allowed", T_Def);
1033 -- Associate the Itype node with the inner full-type declaration or
1034 -- subprogram spec or entry body. This is required to handle nested
1035 -- anonymous declarations. For example:
1038 -- (X : access procedure
1039 -- (Y : access procedure
1042 D_Ityp := Associated_Node_For_Itype (Desig_Type);
1043 while not (Nkind_In (D_Ityp, N_Full_Type_Declaration,
1044 N_Private_Type_Declaration,
1045 N_Private_Extension_Declaration,
1046 N_Procedure_Specification,
1047 N_Function_Specification,
1051 Nkind_In (D_Ityp, N_Object_Declaration,
1052 N_Object_Renaming_Declaration,
1053 N_Formal_Object_Declaration,
1054 N_Formal_Type_Declaration,
1055 N_Task_Type_Declaration,
1056 N_Protected_Type_Declaration))
1058 D_Ityp := Parent (D_Ityp);
1059 pragma Assert (D_Ityp /= Empty);
1062 Set_Associated_Node_For_Itype (Desig_Type, D_Ityp);
1064 if Nkind_In (D_Ityp, N_Procedure_Specification,
1065 N_Function_Specification)
1067 Set_Scope (Desig_Type, Scope (Defining_Entity (D_Ityp)));
1069 elsif Nkind_In (D_Ityp, N_Full_Type_Declaration,
1070 N_Object_Declaration,
1071 N_Object_Renaming_Declaration,
1072 N_Formal_Type_Declaration)
1074 Set_Scope (Desig_Type, Scope (Defining_Identifier (D_Ityp)));
1077 if Nkind (T_Def) = N_Access_Function_Definition then
1078 if Nkind (Result_Definition (T_Def)) = N_Access_Definition then
1080 Acc : constant Node_Id := Result_Definition (T_Def);
1083 if Present (Access_To_Subprogram_Definition (Acc))
1085 Protected_Present (Access_To_Subprogram_Definition (Acc))
1089 Replace_Anonymous_Access_To_Protected_Subprogram
1095 Access_Definition (T_Def, Result_Definition (T_Def)));
1100 Analyze (Result_Definition (T_Def));
1103 Typ : constant Entity_Id := Entity (Result_Definition (T_Def));
1106 -- If a null exclusion is imposed on the result type, then
1107 -- create a null-excluding itype (an access subtype) and use
1108 -- it as the function's Etype.
1110 if Is_Access_Type (Typ)
1111 and then Null_Exclusion_In_Return_Present (T_Def)
1113 Set_Etype (Desig_Type,
1114 Create_Null_Excluding_Itype
1116 Related_Nod => T_Def,
1117 Scope_Id => Current_Scope));
1120 if From_With_Type (Typ) then
1122 -- AI05-151: Incomplete types are allowed in all basic
1123 -- declarations, including access to subprograms.
1125 if Ada_Version >= Ada_2012 then
1130 ("illegal use of incomplete type&",
1131 Result_Definition (T_Def), Typ);
1134 elsif Ekind (Current_Scope) = E_Package
1135 and then In_Private_Part (Current_Scope)
1137 if Ekind (Typ) = E_Incomplete_Type then
1138 Append_Elmt (Desig_Type, Private_Dependents (Typ));
1140 elsif Is_Class_Wide_Type (Typ)
1141 and then Ekind (Etype (Typ)) = E_Incomplete_Type
1144 (Desig_Type, Private_Dependents (Etype (Typ)));
1148 Set_Etype (Desig_Type, Typ);
1153 if not (Is_Type (Etype (Desig_Type))) then
1155 ("expect type in function specification",
1156 Result_Definition (T_Def));
1160 Set_Etype (Desig_Type, Standard_Void_Type);
1163 if Present (Formals) then
1164 Push_Scope (Desig_Type);
1166 -- A bit of a kludge here. These kludges will be removed when Itypes
1167 -- have proper parent pointers to their declarations???
1169 -- Kludge 1) Link defining_identifier of formals. Required by
1170 -- First_Formal to provide its functionality.
1176 F := First (Formals);
1178 -- In ASIS mode, the access_to_subprogram may be analyzed twice,
1179 -- when it is part of an unconstrained type and subtype expansion
1180 -- is disabled. To avoid back-end problems with shared profiles,
1181 -- use previous subprogram type as the designated type.
1184 and then Present (Scope (Defining_Identifier (F)))
1186 Set_Etype (T_Name, T_Name);
1187 Init_Size_Align (T_Name);
1188 Set_Directly_Designated_Type (T_Name,
1189 Scope (Defining_Identifier (F)));
1193 while Present (F) loop
1194 if No (Parent (Defining_Identifier (F))) then
1195 Set_Parent (Defining_Identifier (F), F);
1202 Process_Formals (Formals, Parent (T_Def));
1204 -- Kludge 2) End_Scope requires that the parent pointer be set to
1205 -- something reasonable, but Itypes don't have parent pointers. So
1206 -- we set it and then unset it ???
1208 Set_Parent (Desig_Type, T_Name);
1210 Set_Parent (Desig_Type, Empty);
1213 -- Check for premature usage of the type being defined
1215 Check_For_Premature_Usage (T_Def);
1217 -- The return type and/or any parameter type may be incomplete. Mark
1218 -- the subprogram_type as depending on the incomplete type, so that
1219 -- it can be updated when the full type declaration is seen. This
1220 -- only applies to incomplete types declared in some enclosing scope,
1221 -- not to limited views from other packages.
1223 if Present (Formals) then
1224 Formal := First_Formal (Desig_Type);
1225 while Present (Formal) loop
1226 if Ekind (Formal) /= E_In_Parameter
1227 and then Nkind (T_Def) = N_Access_Function_Definition
1229 Error_Msg_N ("functions can only have IN parameters", Formal);
1232 if Ekind (Etype (Formal)) = E_Incomplete_Type
1233 and then In_Open_Scopes (Scope (Etype (Formal)))
1235 Append_Elmt (Desig_Type, Private_Dependents (Etype (Formal)));
1236 Set_Has_Delayed_Freeze (Desig_Type);
1239 Next_Formal (Formal);
1243 -- If the return type is incomplete, this is legal as long as the
1244 -- type is declared in the current scope and will be completed in
1245 -- it (rather than being part of limited view).
1247 if Ekind (Etype (Desig_Type)) = E_Incomplete_Type
1248 and then not Has_Delayed_Freeze (Desig_Type)
1249 and then In_Open_Scopes (Scope (Etype (Desig_Type)))
1251 Append_Elmt (Desig_Type, Private_Dependents (Etype (Desig_Type)));
1252 Set_Has_Delayed_Freeze (Desig_Type);
1255 Check_Delayed_Subprogram (Desig_Type);
1257 if Protected_Present (T_Def) then
1258 Set_Ekind (T_Name, E_Access_Protected_Subprogram_Type);
1259 Set_Convention (Desig_Type, Convention_Protected);
1261 Set_Ekind (T_Name, E_Access_Subprogram_Type);
1264 Set_Can_Use_Internal_Rep (T_Name, not Always_Compatible_Rep_On_Target);
1266 Set_Etype (T_Name, T_Name);
1267 Init_Size_Align (T_Name);
1268 Set_Directly_Designated_Type (T_Name, Desig_Type);
1270 -- Ada 2005 (AI-231): Propagate the null-excluding attribute
1272 Set_Can_Never_Be_Null (T_Name, Null_Exclusion_Present (T_Def));
1274 Check_Restriction (No_Access_Subprograms, T_Def);
1275 end Access_Subprogram_Declaration;
1277 ----------------------------
1278 -- Access_Type_Declaration --
1279 ----------------------------
1281 procedure Access_Type_Declaration (T : Entity_Id; Def : Node_Id) is
1282 P : constant Node_Id := Parent (Def);
1283 S : constant Node_Id := Subtype_Indication (Def);
1285 Full_Desig : Entity_Id;
1288 Check_SPARK_Restriction ("access type is not allowed", Def);
1290 -- Check for permissible use of incomplete type
1292 if Nkind (S) /= N_Subtype_Indication then
1295 if Ekind (Root_Type (Entity (S))) = E_Incomplete_Type then
1296 Set_Directly_Designated_Type (T, Entity (S));
1298 Set_Directly_Designated_Type (T,
1299 Process_Subtype (S, P, T, 'P'));
1303 Set_Directly_Designated_Type (T,
1304 Process_Subtype (S, P, T, 'P'));
1307 if All_Present (Def) or Constant_Present (Def) then
1308 Set_Ekind (T, E_General_Access_Type);
1310 Set_Ekind (T, E_Access_Type);
1313 Full_Desig := Designated_Type (T);
1315 if Base_Type (Full_Desig) = T then
1316 Error_Msg_N ("access type cannot designate itself", S);
1318 -- In Ada 2005, the type may have a limited view through some unit
1319 -- in its own context, allowing the following circularity that cannot
1320 -- be detected earlier
1322 elsif Is_Class_Wide_Type (Full_Desig)
1323 and then Etype (Full_Desig) = T
1326 ("access type cannot designate its own classwide type", S);
1328 -- Clean up indication of tagged status to prevent cascaded errors
1330 Set_Is_Tagged_Type (T, False);
1335 -- If the type has appeared already in a with_type clause, it is
1336 -- frozen and the pointer size is already set. Else, initialize.
1338 if not From_With_Type (T) then
1339 Init_Size_Align (T);
1342 -- Note that Has_Task is always false, since the access type itself
1343 -- is not a task type. See Einfo for more description on this point.
1344 -- Exactly the same consideration applies to Has_Controlled_Component.
1346 Set_Has_Task (T, False);
1347 Set_Has_Controlled_Component (T, False);
1349 -- Initialize Associated_Collection explicitly to Empty, to avoid
1350 -- problems where an incomplete view of this entity has been previously
1351 -- established by a limited with and an overlaid version of this field
1352 -- (Stored_Constraint) was initialized for the incomplete view.
1354 -- This reset is performed in most cases except where the access type
1355 -- has been created for the purposes of allocating or deallocating a
1356 -- build-in-place object. Such access types have explicitly set pools
1359 if No (Associated_Storage_Pool (T)) then
1360 Set_Associated_Collection (T, Empty);
1363 -- Ada 2005 (AI-231): Propagate the null-excluding and access-constant
1366 Set_Can_Never_Be_Null (T, Null_Exclusion_Present (Def));
1367 Set_Is_Access_Constant (T, Constant_Present (Def));
1368 end Access_Type_Declaration;
1370 ----------------------------------
1371 -- Add_Interface_Tag_Components --
1372 ----------------------------------
1374 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id) is
1375 Loc : constant Source_Ptr := Sloc (N);
1379 procedure Add_Tag (Iface : Entity_Id);
1380 -- Add tag for one of the progenitor interfaces
1386 procedure Add_Tag (Iface : Entity_Id) is
1393 pragma Assert (Is_Tagged_Type (Iface)
1394 and then Is_Interface (Iface));
1396 -- This is a reasonable place to propagate predicates
1398 if Has_Predicates (Iface) then
1399 Set_Has_Predicates (Typ);
1403 Make_Component_Definition (Loc,
1404 Aliased_Present => True,
1405 Subtype_Indication =>
1406 New_Occurrence_Of (RTE (RE_Interface_Tag), Loc));
1408 Tag := Make_Temporary (Loc, 'V');
1411 Make_Component_Declaration (Loc,
1412 Defining_Identifier => Tag,
1413 Component_Definition => Def);
1415 Analyze_Component_Declaration (Decl);
1417 Set_Analyzed (Decl);
1418 Set_Ekind (Tag, E_Component);
1420 Set_Is_Aliased (Tag);
1421 Set_Related_Type (Tag, Iface);
1422 Init_Component_Location (Tag);
1424 pragma Assert (Is_Frozen (Iface));
1426 Set_DT_Entry_Count (Tag,
1427 DT_Entry_Count (First_Entity (Iface)));
1429 if No (Last_Tag) then
1432 Insert_After (Last_Tag, Decl);
1437 -- If the ancestor has discriminants we need to give special support
1438 -- to store the offset_to_top value of the secondary dispatch tables.
1439 -- For this purpose we add a supplementary component just after the
1440 -- field that contains the tag associated with each secondary DT.
1442 if Typ /= Etype (Typ)
1443 and then Has_Discriminants (Etype (Typ))
1446 Make_Component_Definition (Loc,
1447 Subtype_Indication =>
1448 New_Occurrence_Of (RTE (RE_Storage_Offset), Loc));
1450 Offset := Make_Temporary (Loc, 'V');
1453 Make_Component_Declaration (Loc,
1454 Defining_Identifier => Offset,
1455 Component_Definition => Def);
1457 Analyze_Component_Declaration (Decl);
1459 Set_Analyzed (Decl);
1460 Set_Ekind (Offset, E_Component);
1461 Set_Is_Aliased (Offset);
1462 Set_Related_Type (Offset, Iface);
1463 Init_Component_Location (Offset);
1464 Insert_After (Last_Tag, Decl);
1475 -- Start of processing for Add_Interface_Tag_Components
1478 if not RTE_Available (RE_Interface_Tag) then
1480 ("(Ada 2005) interface types not supported by this run-time!",
1485 if Ekind (Typ) /= E_Record_Type
1486 or else (Is_Concurrent_Record_Type (Typ)
1487 and then Is_Empty_List (Abstract_Interface_List (Typ)))
1488 or else (not Is_Concurrent_Record_Type (Typ)
1489 and then No (Interfaces (Typ))
1490 and then Is_Empty_Elmt_List (Interfaces (Typ)))
1495 -- Find the current last tag
1497 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1498 Ext := Record_Extension_Part (Type_Definition (N));
1500 pragma Assert (Nkind (Type_Definition (N)) = N_Record_Definition);
1501 Ext := Type_Definition (N);
1506 if not (Present (Component_List (Ext))) then
1507 Set_Null_Present (Ext, False);
1509 Set_Component_List (Ext,
1510 Make_Component_List (Loc,
1511 Component_Items => L,
1512 Null_Present => False));
1514 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1515 L := Component_Items
1517 (Record_Extension_Part
1518 (Type_Definition (N))));
1520 L := Component_Items
1522 (Type_Definition (N)));
1525 -- Find the last tag component
1528 while Present (Comp) loop
1529 if Nkind (Comp) = N_Component_Declaration
1530 and then Is_Tag (Defining_Identifier (Comp))
1539 -- At this point L references the list of components and Last_Tag
1540 -- references the current last tag (if any). Now we add the tag
1541 -- corresponding with all the interfaces that are not implemented
1544 if Present (Interfaces (Typ)) then
1545 Elmt := First_Elmt (Interfaces (Typ));
1546 while Present (Elmt) loop
1547 Add_Tag (Node (Elmt));
1551 end Add_Interface_Tag_Components;
1553 -------------------------------------
1554 -- Add_Internal_Interface_Entities --
1555 -------------------------------------
1557 procedure Add_Internal_Interface_Entities (Tagged_Type : Entity_Id) is
1560 Iface_Elmt : Elmt_Id;
1561 Iface_Prim : Entity_Id;
1562 Ifaces_List : Elist_Id;
1563 New_Subp : Entity_Id := Empty;
1565 Restore_Scope : Boolean := False;
1568 pragma Assert (Ada_Version >= Ada_2005
1569 and then Is_Record_Type (Tagged_Type)
1570 and then Is_Tagged_Type (Tagged_Type)
1571 and then Has_Interfaces (Tagged_Type)
1572 and then not Is_Interface (Tagged_Type));
1574 -- Ensure that the internal entities are added to the scope of the type
1576 if Scope (Tagged_Type) /= Current_Scope then
1577 Push_Scope (Scope (Tagged_Type));
1578 Restore_Scope := True;
1581 Collect_Interfaces (Tagged_Type, Ifaces_List);
1583 Iface_Elmt := First_Elmt (Ifaces_List);
1584 while Present (Iface_Elmt) loop
1585 Iface := Node (Iface_Elmt);
1587 -- Originally we excluded here from this processing interfaces that
1588 -- are parents of Tagged_Type because their primitives are located
1589 -- in the primary dispatch table (and hence no auxiliary internal
1590 -- entities are required to handle secondary dispatch tables in such
1591 -- case). However, these auxiliary entities are also required to
1592 -- handle derivations of interfaces in formals of generics (see
1593 -- Derive_Subprograms).
1595 Elmt := First_Elmt (Primitive_Operations (Iface));
1596 while Present (Elmt) loop
1597 Iface_Prim := Node (Elmt);
1599 if not Is_Predefined_Dispatching_Operation (Iface_Prim) then
1601 Find_Primitive_Covering_Interface
1602 (Tagged_Type => Tagged_Type,
1603 Iface_Prim => Iface_Prim);
1605 pragma Assert (Present (Prim));
1607 -- Ada 2012 (AI05-0197): If the name of the covering primitive
1608 -- differs from the name of the interface primitive then it is
1609 -- a private primitive inherited from a parent type. In such
1610 -- case, given that Tagged_Type covers the interface, the
1611 -- inherited private primitive becomes visible. For such
1612 -- purpose we add a new entity that renames the inherited
1613 -- private primitive.
1615 if Chars (Prim) /= Chars (Iface_Prim) then
1616 pragma Assert (Has_Suffix (Prim, 'P'));
1618 (New_Subp => New_Subp,
1619 Parent_Subp => Iface_Prim,
1620 Derived_Type => Tagged_Type,
1621 Parent_Type => Iface);
1622 Set_Alias (New_Subp, Prim);
1623 Set_Is_Abstract_Subprogram
1624 (New_Subp, Is_Abstract_Subprogram (Prim));
1628 (New_Subp => New_Subp,
1629 Parent_Subp => Iface_Prim,
1630 Derived_Type => Tagged_Type,
1631 Parent_Type => Iface);
1633 -- Ada 2005 (AI-251): Decorate internal entity Iface_Subp
1634 -- associated with interface types. These entities are
1635 -- only registered in the list of primitives of its
1636 -- corresponding tagged type because they are only used
1637 -- to fill the contents of the secondary dispatch tables.
1638 -- Therefore they are removed from the homonym chains.
1640 Set_Is_Hidden (New_Subp);
1641 Set_Is_Internal (New_Subp);
1642 Set_Alias (New_Subp, Prim);
1643 Set_Is_Abstract_Subprogram
1644 (New_Subp, Is_Abstract_Subprogram (Prim));
1645 Set_Interface_Alias (New_Subp, Iface_Prim);
1647 -- Internal entities associated with interface types are
1648 -- only registered in the list of primitives of the tagged
1649 -- type. They are only used to fill the contents of the
1650 -- secondary dispatch tables. Therefore they are not needed
1651 -- in the homonym chains.
1653 Remove_Homonym (New_Subp);
1655 -- Hidden entities associated with interfaces must have set
1656 -- the Has_Delay_Freeze attribute to ensure that, in case of
1657 -- locally defined tagged types (or compiling with static
1658 -- dispatch tables generation disabled) the corresponding
1659 -- entry of the secondary dispatch table is filled when
1660 -- such an entity is frozen.
1662 Set_Has_Delayed_Freeze (New_Subp);
1668 Next_Elmt (Iface_Elmt);
1671 if Restore_Scope then
1674 end Add_Internal_Interface_Entities;
1676 -----------------------------------
1677 -- Analyze_Component_Declaration --
1678 -----------------------------------
1680 procedure Analyze_Component_Declaration (N : Node_Id) is
1681 Id : constant Entity_Id := Defining_Identifier (N);
1682 E : constant Node_Id := Expression (N);
1683 Typ : constant Node_Id :=
1684 Subtype_Indication (Component_Definition (N));
1688 function Contains_POC (Constr : Node_Id) return Boolean;
1689 -- Determines whether a constraint uses the discriminant of a record
1690 -- type thus becoming a per-object constraint (POC).
1692 function Is_Known_Limited (Typ : Entity_Id) return Boolean;
1693 -- Typ is the type of the current component, check whether this type is
1694 -- a limited type. Used to validate declaration against that of
1695 -- enclosing record.
1701 function Contains_POC (Constr : Node_Id) return Boolean is
1703 -- Prevent cascaded errors
1705 if Error_Posted (Constr) then
1709 case Nkind (Constr) is
1710 when N_Attribute_Reference =>
1712 Attribute_Name (Constr) = Name_Access
1713 and then Prefix (Constr) = Scope (Entity (Prefix (Constr)));
1715 when N_Discriminant_Association =>
1716 return Denotes_Discriminant (Expression (Constr));
1718 when N_Identifier =>
1719 return Denotes_Discriminant (Constr);
1721 when N_Index_Or_Discriminant_Constraint =>
1726 IDC := First (Constraints (Constr));
1727 while Present (IDC) loop
1729 -- One per-object constraint is sufficient
1731 if Contains_POC (IDC) then
1742 return Denotes_Discriminant (Low_Bound (Constr))
1744 Denotes_Discriminant (High_Bound (Constr));
1746 when N_Range_Constraint =>
1747 return Denotes_Discriminant (Range_Expression (Constr));
1755 ----------------------
1756 -- Is_Known_Limited --
1757 ----------------------
1759 function Is_Known_Limited (Typ : Entity_Id) return Boolean is
1760 P : constant Entity_Id := Etype (Typ);
1761 R : constant Entity_Id := Root_Type (Typ);
1764 if Is_Limited_Record (Typ) then
1767 -- If the root type is limited (and not a limited interface)
1768 -- so is the current type
1770 elsif Is_Limited_Record (R)
1772 (not Is_Interface (R)
1773 or else not Is_Limited_Interface (R))
1777 -- Else the type may have a limited interface progenitor, but a
1778 -- limited record parent.
1781 and then Is_Limited_Record (P)
1788 end Is_Known_Limited;
1790 -- Start of processing for Analyze_Component_Declaration
1793 Generate_Definition (Id);
1796 if Present (Typ) then
1797 T := Find_Type_Of_Object
1798 (Subtype_Indication (Component_Definition (N)), N);
1800 if not Nkind_In (Typ, N_Identifier, N_Expanded_Name) then
1801 Check_SPARK_Restriction ("subtype mark required", Typ);
1804 -- Ada 2005 (AI-230): Access Definition case
1807 pragma Assert (Present
1808 (Access_Definition (Component_Definition (N))));
1810 T := Access_Definition
1812 N => Access_Definition (Component_Definition (N)));
1813 Set_Is_Local_Anonymous_Access (T);
1815 -- Ada 2005 (AI-254)
1817 if Present (Access_To_Subprogram_Definition
1818 (Access_Definition (Component_Definition (N))))
1819 and then Protected_Present (Access_To_Subprogram_Definition
1821 (Component_Definition (N))))
1823 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1827 -- If the subtype is a constrained subtype of the enclosing record,
1828 -- (which must have a partial view) the back-end does not properly
1829 -- handle the recursion. Rewrite the component declaration with an
1830 -- explicit subtype indication, which is acceptable to Gigi. We can copy
1831 -- the tree directly because side effects have already been removed from
1832 -- discriminant constraints.
1834 if Ekind (T) = E_Access_Subtype
1835 and then Is_Entity_Name (Subtype_Indication (Component_Definition (N)))
1836 and then Comes_From_Source (T)
1837 and then Nkind (Parent (T)) = N_Subtype_Declaration
1838 and then Etype (Directly_Designated_Type (T)) = Current_Scope
1841 (Subtype_Indication (Component_Definition (N)),
1842 New_Copy_Tree (Subtype_Indication (Parent (T))));
1843 T := Find_Type_Of_Object
1844 (Subtype_Indication (Component_Definition (N)), N);
1847 -- If the component declaration includes a default expression, then we
1848 -- check that the component is not of a limited type (RM 3.7(5)),
1849 -- and do the special preanalysis of the expression (see section on
1850 -- "Handling of Default and Per-Object Expressions" in the spec of
1854 Check_SPARK_Restriction ("default expression is not allowed", E);
1855 Preanalyze_Spec_Expression (E, T);
1856 Check_Initialization (T, E);
1858 if Ada_Version >= Ada_2005
1859 and then Ekind (T) = E_Anonymous_Access_Type
1860 and then Etype (E) /= Any_Type
1862 -- Check RM 3.9.2(9): "if the expected type for an expression is
1863 -- an anonymous access-to-specific tagged type, then the object
1864 -- designated by the expression shall not be dynamically tagged
1865 -- unless it is a controlling operand in a call on a dispatching
1868 if Is_Tagged_Type (Directly_Designated_Type (T))
1870 Ekind (Directly_Designated_Type (T)) /= E_Class_Wide_Type
1872 Ekind (Directly_Designated_Type (Etype (E))) =
1876 ("access to specific tagged type required (RM 3.9.2(9))", E);
1879 -- (Ada 2005: AI-230): Accessibility check for anonymous
1882 if Type_Access_Level (Etype (E)) > Type_Access_Level (T) then
1884 ("expression has deeper access level than component " &
1885 "(RM 3.10.2 (12.2))", E);
1888 -- The initialization expression is a reference to an access
1889 -- discriminant. The type of the discriminant is always deeper
1890 -- than any access type.
1892 if Ekind (Etype (E)) = E_Anonymous_Access_Type
1893 and then Is_Entity_Name (E)
1894 and then Ekind (Entity (E)) = E_In_Parameter
1895 and then Present (Discriminal_Link (Entity (E)))
1898 ("discriminant has deeper accessibility level than target",
1904 -- The parent type may be a private view with unknown discriminants,
1905 -- and thus unconstrained. Regular components must be constrained.
1907 if Is_Indefinite_Subtype (T) and then Chars (Id) /= Name_uParent then
1908 if Is_Class_Wide_Type (T) then
1910 ("class-wide subtype with unknown discriminants" &
1911 " in component declaration",
1912 Subtype_Indication (Component_Definition (N)));
1915 ("unconstrained subtype in component declaration",
1916 Subtype_Indication (Component_Definition (N)));
1919 -- Components cannot be abstract, except for the special case of
1920 -- the _Parent field (case of extending an abstract tagged type)
1922 elsif Is_Abstract_Type (T) and then Chars (Id) /= Name_uParent then
1923 Error_Msg_N ("type of a component cannot be abstract", N);
1927 Set_Is_Aliased (Id, Aliased_Present (Component_Definition (N)));
1929 -- The component declaration may have a per-object constraint, set
1930 -- the appropriate flag in the defining identifier of the subtype.
1932 if Present (Subtype_Indication (Component_Definition (N))) then
1934 Sindic : constant Node_Id :=
1935 Subtype_Indication (Component_Definition (N));
1937 if Nkind (Sindic) = N_Subtype_Indication
1938 and then Present (Constraint (Sindic))
1939 and then Contains_POC (Constraint (Sindic))
1941 Set_Has_Per_Object_Constraint (Id);
1946 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
1947 -- out some static checks.
1949 if Ada_Version >= Ada_2005
1950 and then Can_Never_Be_Null (T)
1952 Null_Exclusion_Static_Checks (N);
1955 -- If this component is private (or depends on a private type), flag the
1956 -- record type to indicate that some operations are not available.
1958 P := Private_Component (T);
1962 -- Check for circular definitions
1964 if P = Any_Type then
1965 Set_Etype (Id, Any_Type);
1967 -- There is a gap in the visibility of operations only if the
1968 -- component type is not defined in the scope of the record type.
1970 elsif Scope (P) = Scope (Current_Scope) then
1973 elsif Is_Limited_Type (P) then
1974 Set_Is_Limited_Composite (Current_Scope);
1977 Set_Is_Private_Composite (Current_Scope);
1982 and then Is_Limited_Type (T)
1983 and then Chars (Id) /= Name_uParent
1984 and then Is_Tagged_Type (Current_Scope)
1986 if Is_Derived_Type (Current_Scope)
1987 and then not Is_Known_Limited (Current_Scope)
1990 ("extension of nonlimited type cannot have limited components",
1993 if Is_Interface (Root_Type (Current_Scope)) then
1995 ("\limitedness is not inherited from limited interface", N);
1996 Error_Msg_N ("\add LIMITED to type indication", N);
1999 Explain_Limited_Type (T, N);
2000 Set_Etype (Id, Any_Type);
2001 Set_Is_Limited_Composite (Current_Scope, False);
2003 elsif not Is_Derived_Type (Current_Scope)
2004 and then not Is_Limited_Record (Current_Scope)
2005 and then not Is_Concurrent_Type (Current_Scope)
2008 ("nonlimited tagged type cannot have limited components", N);
2009 Explain_Limited_Type (T, N);
2010 Set_Etype (Id, Any_Type);
2011 Set_Is_Limited_Composite (Current_Scope, False);
2015 Set_Original_Record_Component (Id, Id);
2017 if Has_Aspects (N) then
2018 Analyze_Aspect_Specifications (N, Id);
2020 end Analyze_Component_Declaration;
2022 --------------------------
2023 -- Analyze_Declarations --
2024 --------------------------
2026 procedure Analyze_Declarations (L : List_Id) is
2028 Freeze_From : Entity_Id := Empty;
2029 Next_Node : Node_Id;
2032 -- Adjust D not to include implicit label declarations, since these
2033 -- have strange Sloc values that result in elaboration check problems.
2034 -- (They have the sloc of the label as found in the source, and that
2035 -- is ahead of the current declarative part).
2041 procedure Adjust_D is
2043 while Present (Prev (D))
2044 and then Nkind (D) = N_Implicit_Label_Declaration
2050 -- Start of processing for Analyze_Declarations
2053 if SPARK_Mode or else Restriction_Check_Required (SPARK) then
2054 Check_Later_Vs_Basic_Declarations (L, During_Parsing => False);
2058 while Present (D) loop
2060 -- Package specification cannot contain a package declaration in
2063 if Nkind (D) = N_Package_Declaration
2064 and then Nkind (Parent (L)) = N_Package_Specification
2066 Check_SPARK_Restriction ("package specification cannot contain "
2067 & "a package declaration", D);
2070 -- Complete analysis of declaration
2073 Next_Node := Next (D);
2075 if No (Freeze_From) then
2076 Freeze_From := First_Entity (Current_Scope);
2079 -- At the end of a declarative part, freeze remaining entities
2080 -- declared in it. The end of the visible declarations of package
2081 -- specification is not the end of a declarative part if private
2082 -- declarations are present. The end of a package declaration is a
2083 -- freezing point only if it a library package. A task definition or
2084 -- protected type definition is not a freeze point either. Finally,
2085 -- we do not freeze entities in generic scopes, because there is no
2086 -- code generated for them and freeze nodes will be generated for
2089 -- The end of a package instantiation is not a freeze point, but
2090 -- for now we make it one, because the generic body is inserted
2091 -- (currently) immediately after. Generic instantiations will not
2092 -- be a freeze point once delayed freezing of bodies is implemented.
2093 -- (This is needed in any case for early instantiations ???).
2095 if No (Next_Node) then
2096 if Nkind_In (Parent (L), N_Component_List,
2098 N_Protected_Definition)
2102 elsif Nkind (Parent (L)) /= N_Package_Specification then
2103 if Nkind (Parent (L)) = N_Package_Body then
2104 Freeze_From := First_Entity (Current_Scope);
2108 Freeze_All (Freeze_From, D);
2109 Freeze_From := Last_Entity (Current_Scope);
2111 elsif Scope (Current_Scope) /= Standard_Standard
2112 and then not Is_Child_Unit (Current_Scope)
2113 and then No (Generic_Parent (Parent (L)))
2117 elsif L /= Visible_Declarations (Parent (L))
2118 or else No (Private_Declarations (Parent (L)))
2119 or else Is_Empty_List (Private_Declarations (Parent (L)))
2122 Freeze_All (Freeze_From, D);
2123 Freeze_From := Last_Entity (Current_Scope);
2126 -- If next node is a body then freeze all types before the body.
2127 -- An exception occurs for some expander-generated bodies. If these
2128 -- are generated at places where in general language rules would not
2129 -- allow a freeze point, then we assume that the expander has
2130 -- explicitly checked that all required types are properly frozen,
2131 -- and we do not cause general freezing here. This special circuit
2132 -- is used when the encountered body is marked as having already
2135 -- In all other cases (bodies that come from source, and expander
2136 -- generated bodies that have not been analyzed yet), freeze all
2137 -- types now. Note that in the latter case, the expander must take
2138 -- care to attach the bodies at a proper place in the tree so as to
2139 -- not cause unwanted freezing at that point.
2141 elsif not Analyzed (Next_Node)
2142 and then (Nkind_In (Next_Node, N_Subprogram_Body,
2148 Nkind (Next_Node) in N_Body_Stub)
2151 Freeze_All (Freeze_From, D);
2152 Freeze_From := Last_Entity (Current_Scope);
2158 -- One more thing to do, we need to scan the declarations to check
2159 -- for any precondition/postcondition pragmas (Pre/Post aspects have
2160 -- by this stage been converted into corresponding pragmas). It is
2161 -- at this point that we analyze the expressions in such pragmas,
2162 -- to implement the delayed visibility requirement.
2172 while Present (Decl) loop
2173 if Nkind (Original_Node (Decl)) = N_Subprogram_Declaration then
2174 Spec := Specification (Original_Node (Decl));
2175 Sent := Defining_Unit_Name (Spec);
2176 Prag := Spec_PPC_List (Sent);
2177 while Present (Prag) loop
2178 Analyze_PPC_In_Decl_Part (Prag, Sent);
2179 Prag := Next_Pragma (Prag);
2186 end Analyze_Declarations;
2188 -----------------------------------
2189 -- Analyze_Full_Type_Declaration --
2190 -----------------------------------
2192 procedure Analyze_Full_Type_Declaration (N : Node_Id) is
2193 Def : constant Node_Id := Type_Definition (N);
2194 Def_Id : constant Entity_Id := Defining_Identifier (N);
2198 Is_Remote : constant Boolean :=
2199 (Is_Remote_Types (Current_Scope)
2200 or else Is_Remote_Call_Interface (Current_Scope))
2201 and then not (In_Private_Part (Current_Scope)
2202 or else In_Package_Body (Current_Scope));
2204 procedure Check_Ops_From_Incomplete_Type;
2205 -- If there is a tagged incomplete partial view of the type, traverse
2206 -- the primitives of the incomplete view and change the type of any
2207 -- controlling formals and result to indicate the full view. The
2208 -- primitives will be added to the full type's primitive operations
2209 -- list later in Sem_Disp.Check_Operation_From_Incomplete_Type (which
2210 -- is called from Process_Incomplete_Dependents).
2212 ------------------------------------
2213 -- Check_Ops_From_Incomplete_Type --
2214 ------------------------------------
2216 procedure Check_Ops_From_Incomplete_Type is
2223 and then Ekind (Prev) = E_Incomplete_Type
2224 and then Is_Tagged_Type (Prev)
2225 and then Is_Tagged_Type (T)
2227 Elmt := First_Elmt (Primitive_Operations (Prev));
2228 while Present (Elmt) loop
2231 Formal := First_Formal (Op);
2232 while Present (Formal) loop
2233 if Etype (Formal) = Prev then
2234 Set_Etype (Formal, T);
2237 Next_Formal (Formal);
2240 if Etype (Op) = Prev then
2247 end Check_Ops_From_Incomplete_Type;
2249 -- Start of processing for Analyze_Full_Type_Declaration
2252 Prev := Find_Type_Name (N);
2254 -- The full view, if present, now points to the current type
2256 -- Ada 2005 (AI-50217): If the type was previously decorated when
2257 -- imported through a LIMITED WITH clause, it appears as incomplete
2258 -- but has no full view.
2260 if Ekind (Prev) = E_Incomplete_Type
2261 and then Present (Full_View (Prev))
2263 T := Full_View (Prev);
2268 Set_Is_Pure (T, Is_Pure (Current_Scope));
2270 -- We set the flag Is_First_Subtype here. It is needed to set the
2271 -- corresponding flag for the Implicit class-wide-type created
2272 -- during tagged types processing.
2274 Set_Is_First_Subtype (T, True);
2276 -- Only composite types other than array types are allowed to have
2281 -- For derived types, the rule will be checked once we've figured
2282 -- out the parent type.
2284 when N_Derived_Type_Definition =>
2287 -- For record types, discriminants are allowed, unless we are in
2290 when N_Record_Definition =>
2291 if Present (Discriminant_Specifications (N)) then
2292 Check_SPARK_Restriction
2293 ("discriminant type is not allowed",
2295 (First (Discriminant_Specifications (N))));
2299 if Present (Discriminant_Specifications (N)) then
2301 ("elementary or array type cannot have discriminants",
2303 (First (Discriminant_Specifications (N))));
2307 -- Elaborate the type definition according to kind, and generate
2308 -- subsidiary (implicit) subtypes where needed. We skip this if it was
2309 -- already done (this happens during the reanalysis that follows a call
2310 -- to the high level optimizer).
2312 if not Analyzed (T) then
2317 when N_Access_To_Subprogram_Definition =>
2318 Access_Subprogram_Declaration (T, Def);
2320 -- If this is a remote access to subprogram, we must create the
2321 -- equivalent fat pointer type, and related subprograms.
2324 Process_Remote_AST_Declaration (N);
2327 -- Validate categorization rule against access type declaration
2328 -- usually a violation in Pure unit, Shared_Passive unit.
2330 Validate_Access_Type_Declaration (T, N);
2332 when N_Access_To_Object_Definition =>
2333 Access_Type_Declaration (T, Def);
2335 -- Validate categorization rule against access type declaration
2336 -- usually a violation in Pure unit, Shared_Passive unit.
2338 Validate_Access_Type_Declaration (T, N);
2340 -- If we are in a Remote_Call_Interface package and define a
2341 -- RACW, then calling stubs and specific stream attributes
2345 and then Is_Remote_Access_To_Class_Wide_Type (Def_Id)
2347 Add_RACW_Features (Def_Id);
2350 -- Set no strict aliasing flag if config pragma seen
2352 if Opt.No_Strict_Aliasing then
2353 Set_No_Strict_Aliasing (Base_Type (Def_Id));
2356 when N_Array_Type_Definition =>
2357 Array_Type_Declaration (T, Def);
2359 when N_Derived_Type_Definition =>
2360 Derived_Type_Declaration (T, N, T /= Def_Id);
2362 when N_Enumeration_Type_Definition =>
2363 Enumeration_Type_Declaration (T, Def);
2365 when N_Floating_Point_Definition =>
2366 Floating_Point_Type_Declaration (T, Def);
2368 when N_Decimal_Fixed_Point_Definition =>
2369 Decimal_Fixed_Point_Type_Declaration (T, Def);
2371 when N_Ordinary_Fixed_Point_Definition =>
2372 Ordinary_Fixed_Point_Type_Declaration (T, Def);
2374 when N_Signed_Integer_Type_Definition =>
2375 Signed_Integer_Type_Declaration (T, Def);
2377 when N_Modular_Type_Definition =>
2378 Modular_Type_Declaration (T, Def);
2380 when N_Record_Definition =>
2381 Record_Type_Declaration (T, N, Prev);
2383 -- If declaration has a parse error, nothing to elaborate.
2389 raise Program_Error;
2394 if Etype (T) = Any_Type then
2398 -- Controlled type is not allowed in SPARK
2400 if Is_Visibly_Controlled (T) then
2401 Check_SPARK_Restriction ("controlled type is not allowed", N);
2404 -- Some common processing for all types
2406 Set_Depends_On_Private (T, Has_Private_Component (T));
2407 Check_Ops_From_Incomplete_Type;
2409 -- Both the declared entity, and its anonymous base type if one
2410 -- was created, need freeze nodes allocated.
2413 B : constant Entity_Id := Base_Type (T);
2416 -- In the case where the base type differs from the first subtype, we
2417 -- pre-allocate a freeze node, and set the proper link to the first
2418 -- subtype. Freeze_Entity will use this preallocated freeze node when
2419 -- it freezes the entity.
2421 -- This does not apply if the base type is a generic type, whose
2422 -- declaration is independent of the current derived definition.
2424 if B /= T and then not Is_Generic_Type (B) then
2425 Ensure_Freeze_Node (B);
2426 Set_First_Subtype_Link (Freeze_Node (B), T);
2429 -- A type that is imported through a limited_with clause cannot
2430 -- generate any code, and thus need not be frozen. However, an access
2431 -- type with an imported designated type needs a finalization list,
2432 -- which may be referenced in some other package that has non-limited
2433 -- visibility on the designated type. Thus we must create the
2434 -- finalization list at the point the access type is frozen, to
2435 -- prevent unsatisfied references at link time.
2437 if not From_With_Type (T) or else Is_Access_Type (T) then
2438 Set_Has_Delayed_Freeze (T);
2442 -- Case where T is the full declaration of some private type which has
2443 -- been swapped in Defining_Identifier (N).
2445 if T /= Def_Id and then Is_Private_Type (Def_Id) then
2446 Process_Full_View (N, T, Def_Id);
2448 -- Record the reference. The form of this is a little strange, since
2449 -- the full declaration has been swapped in. So the first parameter
2450 -- here represents the entity to which a reference is made which is
2451 -- the "real" entity, i.e. the one swapped in, and the second
2452 -- parameter provides the reference location.
2454 -- Also, we want to kill Has_Pragma_Unreferenced temporarily here
2455 -- since we don't want a complaint about the full type being an
2456 -- unwanted reference to the private type
2459 B : constant Boolean := Has_Pragma_Unreferenced (T);
2461 Set_Has_Pragma_Unreferenced (T, False);
2462 Generate_Reference (T, T, 'c');
2463 Set_Has_Pragma_Unreferenced (T, B);
2466 Set_Completion_Referenced (Def_Id);
2468 -- For completion of incomplete type, process incomplete dependents
2469 -- and always mark the full type as referenced (it is the incomplete
2470 -- type that we get for any real reference).
2472 elsif Ekind (Prev) = E_Incomplete_Type then
2473 Process_Incomplete_Dependents (N, T, Prev);
2474 Generate_Reference (Prev, Def_Id, 'c');
2475 Set_Completion_Referenced (Def_Id);
2477 -- If not private type or incomplete type completion, this is a real
2478 -- definition of a new entity, so record it.
2481 Generate_Definition (Def_Id);
2484 if Chars (Scope (Def_Id)) = Name_System
2485 and then Chars (Def_Id) = Name_Address
2486 and then Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (N)))
2488 Set_Is_Descendent_Of_Address (Def_Id);
2489 Set_Is_Descendent_Of_Address (Base_Type (Def_Id));
2490 Set_Is_Descendent_Of_Address (Prev);
2493 Set_Optimize_Alignment_Flags (Def_Id);
2494 Check_Eliminated (Def_Id);
2496 if Has_Aspects (N) then
2497 Analyze_Aspect_Specifications (N, Def_Id);
2499 end Analyze_Full_Type_Declaration;
2501 ----------------------------------
2502 -- Analyze_Incomplete_Type_Decl --
2503 ----------------------------------
2505 procedure Analyze_Incomplete_Type_Decl (N : Node_Id) is
2506 F : constant Boolean := Is_Pure (Current_Scope);
2510 Check_SPARK_Restriction ("incomplete type is not allowed", N);
2512 Generate_Definition (Defining_Identifier (N));
2514 -- Process an incomplete declaration. The identifier must not have been
2515 -- declared already in the scope. However, an incomplete declaration may
2516 -- appear in the private part of a package, for a private type that has
2517 -- already been declared.
2519 -- In this case, the discriminants (if any) must match
2521 T := Find_Type_Name (N);
2523 Set_Ekind (T, E_Incomplete_Type);
2524 Init_Size_Align (T);
2525 Set_Is_First_Subtype (T, True);
2528 -- Ada 2005 (AI-326): Minimum decoration to give support to tagged
2529 -- incomplete types.
2531 if Tagged_Present (N) then
2532 Set_Is_Tagged_Type (T);
2533 Make_Class_Wide_Type (T);
2534 Set_Direct_Primitive_Operations (T, New_Elmt_List);
2539 Set_Stored_Constraint (T, No_Elist);
2541 if Present (Discriminant_Specifications (N)) then
2542 Process_Discriminants (N);
2547 -- If the type has discriminants, non-trivial subtypes may be
2548 -- declared before the full view of the type. The full views of those
2549 -- subtypes will be built after the full view of the type.
2551 Set_Private_Dependents (T, New_Elmt_List);
2553 end Analyze_Incomplete_Type_Decl;
2555 -----------------------------------
2556 -- Analyze_Interface_Declaration --
2557 -----------------------------------
2559 procedure Analyze_Interface_Declaration (T : Entity_Id; Def : Node_Id) is
2560 CW : constant Entity_Id := Class_Wide_Type (T);
2563 Set_Is_Tagged_Type (T);
2565 Set_Is_Limited_Record (T, Limited_Present (Def)
2566 or else Task_Present (Def)
2567 or else Protected_Present (Def)
2568 or else Synchronized_Present (Def));
2570 -- Type is abstract if full declaration carries keyword, or if previous
2571 -- partial view did.
2573 Set_Is_Abstract_Type (T);
2574 Set_Is_Interface (T);
2576 -- Type is a limited interface if it includes the keyword limited, task,
2577 -- protected, or synchronized.
2579 Set_Is_Limited_Interface
2580 (T, Limited_Present (Def)
2581 or else Protected_Present (Def)
2582 or else Synchronized_Present (Def)
2583 or else Task_Present (Def));
2585 Set_Interfaces (T, New_Elmt_List);
2586 Set_Direct_Primitive_Operations (T, New_Elmt_List);
2588 -- Complete the decoration of the class-wide entity if it was already
2589 -- built (i.e. during the creation of the limited view)
2591 if Present (CW) then
2592 Set_Is_Interface (CW);
2593 Set_Is_Limited_Interface (CW, Is_Limited_Interface (T));
2596 -- Check runtime support for synchronized interfaces
2598 if VM_Target = No_VM
2599 and then (Is_Task_Interface (T)
2600 or else Is_Protected_Interface (T)
2601 or else Is_Synchronized_Interface (T))
2602 and then not RTE_Available (RE_Select_Specific_Data)
2604 Error_Msg_CRT ("synchronized interfaces", T);
2606 end Analyze_Interface_Declaration;
2608 -----------------------------
2609 -- Analyze_Itype_Reference --
2610 -----------------------------
2612 -- Nothing to do. This node is placed in the tree only for the benefit of
2613 -- back end processing, and has no effect on the semantic processing.
2615 procedure Analyze_Itype_Reference (N : Node_Id) is
2617 pragma Assert (Is_Itype (Itype (N)));
2619 end Analyze_Itype_Reference;
2621 --------------------------------
2622 -- Analyze_Number_Declaration --
2623 --------------------------------
2625 procedure Analyze_Number_Declaration (N : Node_Id) is
2626 Id : constant Entity_Id := Defining_Identifier (N);
2627 E : constant Node_Id := Expression (N);
2629 Index : Interp_Index;
2633 Generate_Definition (Id);
2636 -- This is an optimization of a common case of an integer literal
2638 if Nkind (E) = N_Integer_Literal then
2639 Set_Is_Static_Expression (E, True);
2640 Set_Etype (E, Universal_Integer);
2642 Set_Etype (Id, Universal_Integer);
2643 Set_Ekind (Id, E_Named_Integer);
2644 Set_Is_Frozen (Id, True);
2648 Set_Is_Pure (Id, Is_Pure (Current_Scope));
2650 -- Process expression, replacing error by integer zero, to avoid
2651 -- cascaded errors or aborts further along in the processing
2653 -- Replace Error by integer zero, which seems least likely to
2654 -- cause cascaded errors.
2657 Rewrite (E, Make_Integer_Literal (Sloc (E), Uint_0));
2658 Set_Error_Posted (E);
2663 -- Verify that the expression is static and numeric. If
2664 -- the expression is overloaded, we apply the preference
2665 -- rule that favors root numeric types.
2667 if not Is_Overloaded (E) then
2673 Get_First_Interp (E, Index, It);
2674 while Present (It.Typ) loop
2675 if (Is_Integer_Type (It.Typ)
2676 or else Is_Real_Type (It.Typ))
2677 and then (Scope (Base_Type (It.Typ))) = Standard_Standard
2679 if T = Any_Type then
2682 elsif It.Typ = Universal_Real
2683 or else It.Typ = Universal_Integer
2685 -- Choose universal interpretation over any other
2692 Get_Next_Interp (Index, It);
2696 if Is_Integer_Type (T) then
2698 Set_Etype (Id, Universal_Integer);
2699 Set_Ekind (Id, E_Named_Integer);
2701 elsif Is_Real_Type (T) then
2703 -- Because the real value is converted to universal_real, this is a
2704 -- legal context for a universal fixed expression.
2706 if T = Universal_Fixed then
2708 Loc : constant Source_Ptr := Sloc (N);
2709 Conv : constant Node_Id := Make_Type_Conversion (Loc,
2711 New_Occurrence_Of (Universal_Real, Loc),
2712 Expression => Relocate_Node (E));
2719 elsif T = Any_Fixed then
2720 Error_Msg_N ("illegal context for mixed mode operation", E);
2722 -- Expression is of the form : universal_fixed * integer. Try to
2723 -- resolve as universal_real.
2725 T := Universal_Real;
2730 Set_Etype (Id, Universal_Real);
2731 Set_Ekind (Id, E_Named_Real);
2734 Wrong_Type (E, Any_Numeric);
2738 Set_Ekind (Id, E_Constant);
2739 Set_Never_Set_In_Source (Id, True);
2740 Set_Is_True_Constant (Id, True);
2744 if Nkind_In (E, N_Integer_Literal, N_Real_Literal) then
2745 Set_Etype (E, Etype (Id));
2748 if not Is_OK_Static_Expression (E) then
2749 Flag_Non_Static_Expr
2750 ("non-static expression used in number declaration!", E);
2751 Rewrite (E, Make_Integer_Literal (Sloc (N), 1));
2752 Set_Etype (E, Any_Type);
2754 end Analyze_Number_Declaration;
2756 --------------------------------
2757 -- Analyze_Object_Declaration --
2758 --------------------------------
2760 procedure Analyze_Object_Declaration (N : Node_Id) is
2761 Loc : constant Source_Ptr := Sloc (N);
2762 Id : constant Entity_Id := Defining_Identifier (N);
2766 E : Node_Id := Expression (N);
2767 -- E is set to Expression (N) throughout this routine. When
2768 -- Expression (N) is modified, E is changed accordingly.
2770 Prev_Entity : Entity_Id := Empty;
2772 function Count_Tasks (T : Entity_Id) return Uint;
2773 -- This function is called when a non-generic library level object of a
2774 -- task type is declared. Its function is to count the static number of
2775 -- tasks declared within the type (it is only called if Has_Tasks is set
2776 -- for T). As a side effect, if an array of tasks with non-static bounds
2777 -- or a variant record type is encountered, Check_Restrictions is called
2778 -- indicating the count is unknown.
2784 function Count_Tasks (T : Entity_Id) return Uint is
2790 if Is_Task_Type (T) then
2793 elsif Is_Record_Type (T) then
2794 if Has_Discriminants (T) then
2795 Check_Restriction (Max_Tasks, N);
2800 C := First_Component (T);
2801 while Present (C) loop
2802 V := V + Count_Tasks (Etype (C));
2809 elsif Is_Array_Type (T) then
2810 X := First_Index (T);
2811 V := Count_Tasks (Component_Type (T));
2812 while Present (X) loop
2815 if not Is_Static_Subtype (C) then
2816 Check_Restriction (Max_Tasks, N);
2819 V := V * (UI_Max (Uint_0,
2820 Expr_Value (Type_High_Bound (C)) -
2821 Expr_Value (Type_Low_Bound (C)) + Uint_1));
2834 -- Start of processing for Analyze_Object_Declaration
2837 -- There are three kinds of implicit types generated by an
2838 -- object declaration:
2840 -- 1. Those generated by the original Object Definition
2842 -- 2. Those generated by the Expression
2844 -- 3. Those used to constrained the Object Definition with the
2845 -- expression constraints when it is unconstrained
2847 -- They must be generated in this order to avoid order of elaboration
2848 -- issues. Thus the first step (after entering the name) is to analyze
2849 -- the object definition.
2851 if Constant_Present (N) then
2852 Prev_Entity := Current_Entity_In_Scope (Id);
2854 if Present (Prev_Entity)
2856 -- If the homograph is an implicit subprogram, it is overridden
2857 -- by the current declaration.
2859 ((Is_Overloadable (Prev_Entity)
2860 and then Is_Inherited_Operation (Prev_Entity))
2862 -- The current object is a discriminal generated for an entry
2863 -- family index. Even though the index is a constant, in this
2864 -- particular context there is no true constant redeclaration.
2865 -- Enter_Name will handle the visibility.
2868 (Is_Discriminal (Id)
2869 and then Ekind (Discriminal_Link (Id)) =
2870 E_Entry_Index_Parameter)
2872 -- The current object is the renaming for a generic declared
2873 -- within the instance.
2876 (Ekind (Prev_Entity) = E_Package
2877 and then Nkind (Parent (Prev_Entity)) =
2878 N_Package_Renaming_Declaration
2879 and then not Comes_From_Source (Prev_Entity)
2880 and then Is_Generic_Instance (Renamed_Entity (Prev_Entity))))
2882 Prev_Entity := Empty;
2886 if Present (Prev_Entity) then
2887 Constant_Redeclaration (Id, N, T);
2889 Generate_Reference (Prev_Entity, Id, 'c');
2890 Set_Completion_Referenced (Id);
2892 if Error_Posted (N) then
2894 -- Type mismatch or illegal redeclaration, Do not analyze
2895 -- expression to avoid cascaded errors.
2897 T := Find_Type_Of_Object (Object_Definition (N), N);
2899 Set_Ekind (Id, E_Variable);
2903 -- In the normal case, enter identifier at the start to catch premature
2904 -- usage in the initialization expression.
2907 Generate_Definition (Id);
2910 Mark_Coextensions (N, Object_Definition (N));
2912 T := Find_Type_Of_Object (Object_Definition (N), N);
2914 if Nkind (Object_Definition (N)) = N_Access_Definition
2916 (Access_To_Subprogram_Definition (Object_Definition (N)))
2917 and then Protected_Present
2918 (Access_To_Subprogram_Definition (Object_Definition (N)))
2920 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
2923 if Error_Posted (Id) then
2925 Set_Ekind (Id, E_Variable);
2930 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
2931 -- out some static checks
2933 if Ada_Version >= Ada_2005
2934 and then Can_Never_Be_Null (T)
2936 -- In case of aggregates we must also take care of the correct
2937 -- initialization of nested aggregates bug this is done at the
2938 -- point of the analysis of the aggregate (see sem_aggr.adb)
2940 if Present (Expression (N))
2941 and then Nkind (Expression (N)) = N_Aggregate
2947 Save_Typ : constant Entity_Id := Etype (Id);
2949 Set_Etype (Id, T); -- Temp. decoration for static checks
2950 Null_Exclusion_Static_Checks (N);
2951 Set_Etype (Id, Save_Typ);
2956 Set_Is_Pure (Id, Is_Pure (Current_Scope));
2958 -- If deferred constant, make sure context is appropriate. We detect
2959 -- a deferred constant as a constant declaration with no expression.
2960 -- A deferred constant can appear in a package body if its completion
2961 -- is by means of an interface pragma.
2963 if Constant_Present (N)
2966 -- A deferred constant may appear in the declarative part of the
2967 -- following constructs:
2971 -- extended return statements
2974 -- subprogram bodies
2977 -- When declared inside a package spec, a deferred constant must be
2978 -- completed by a full constant declaration or pragma Import. In all
2979 -- other cases, the only proper completion is pragma Import. Extended
2980 -- return statements are flagged as invalid contexts because they do
2981 -- not have a declarative part and so cannot accommodate the pragma.
2983 if Ekind (Current_Scope) = E_Return_Statement then
2985 ("invalid context for deferred constant declaration (RM 7.4)",
2988 ("\declaration requires an initialization expression",
2990 Set_Constant_Present (N, False);
2992 -- In Ada 83, deferred constant must be of private type
2994 elsif not Is_Private_Type (T) then
2995 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
2997 ("(Ada 83) deferred constant must be private type", N);
3001 -- If not a deferred constant, then object declaration freezes its type
3004 Check_Fully_Declared (T, N);
3005 Freeze_Before (N, T);
3008 -- If the object was created by a constrained array definition, then
3009 -- set the link in both the anonymous base type and anonymous subtype
3010 -- that are built to represent the array type to point to the object.
3012 if Nkind (Object_Definition (Declaration_Node (Id))) =
3013 N_Constrained_Array_Definition
3015 Set_Related_Array_Object (T, Id);
3016 Set_Related_Array_Object (Base_Type (T), Id);
3019 -- Special checks for protected objects not at library level
3021 if Is_Protected_Type (T)
3022 and then not Is_Library_Level_Entity (Id)
3024 Check_Restriction (No_Local_Protected_Objects, Id);
3026 -- Protected objects with interrupt handlers must be at library level
3028 -- Ada 2005: this test is not needed (and the corresponding clause
3029 -- in the RM is removed) because accessibility checks are sufficient
3030 -- to make handlers not at the library level illegal.
3032 if Has_Interrupt_Handler (T)
3033 and then Ada_Version < Ada_2005
3036 ("interrupt object can only be declared at library level", Id);
3040 -- The actual subtype of the object is the nominal subtype, unless
3041 -- the nominal one is unconstrained and obtained from the expression.
3045 -- The object is in ALFA if-and-only-if its type is in ALFA and it is
3048 if Is_In_ALFA (T) and then not Aliased_Present (N) then
3049 Set_Is_In_ALFA (Id);
3051 Mark_Non_ALFA_Subprogram;
3054 -- These checks should be performed before the initialization expression
3055 -- is considered, so that the Object_Definition node is still the same
3056 -- as in source code.
3058 -- In SPARK, the nominal subtype shall be given by a subtype mark and
3059 -- shall not be unconstrained. (The only exception to this is the
3060 -- admission of declarations of constants of type String.)
3063 Nkind_In (Object_Definition (N), N_Identifier, N_Expanded_Name)
3065 Check_SPARK_Restriction
3066 ("subtype mark required", Object_Definition (N));
3068 elsif Is_Array_Type (T)
3069 and then not Is_Constrained (T)
3070 and then T /= Standard_String
3072 Check_SPARK_Restriction
3073 ("subtype mark of constrained type expected",
3074 Object_Definition (N));
3077 -- There are no aliased objects in SPARK
3079 if Aliased_Present (N) then
3080 Check_SPARK_Restriction ("aliased object is not allowed", N);
3083 -- Process initialization expression if present and not in error
3085 if Present (E) and then E /= Error then
3087 -- Generate an error in case of CPP class-wide object initialization.
3088 -- Required because otherwise the expansion of the class-wide
3089 -- assignment would try to use 'size to initialize the object
3090 -- (primitive that is not available in CPP tagged types).
3092 if Is_Class_Wide_Type (Act_T)
3094 (Is_CPP_Class (Root_Type (Etype (Act_T)))
3096 (Present (Full_View (Root_Type (Etype (Act_T))))
3098 Is_CPP_Class (Full_View (Root_Type (Etype (Act_T))))))
3101 ("predefined assignment not available for 'C'P'P tagged types",
3105 Mark_Coextensions (N, E);
3108 -- In case of errors detected in the analysis of the expression,
3109 -- decorate it with the expected type to avoid cascaded errors
3111 if No (Etype (E)) then
3115 -- If an initialization expression is present, then we set the
3116 -- Is_True_Constant flag. It will be reset if this is a variable
3117 -- and it is indeed modified.
3119 Set_Is_True_Constant (Id, True);
3121 -- If we are analyzing a constant declaration, set its completion
3122 -- flag after analyzing and resolving the expression.
3124 if Constant_Present (N) then
3125 Set_Has_Completion (Id);
3128 -- Set type and resolve (type may be overridden later on)
3133 -- If E is null and has been replaced by an N_Raise_Constraint_Error
3134 -- node (which was marked already-analyzed), we need to set the type
3135 -- to something other than Any_Access in order to keep gigi happy.
3137 if Etype (E) = Any_Access then
3141 -- If the object is an access to variable, the initialization
3142 -- expression cannot be an access to constant.
3144 if Is_Access_Type (T)
3145 and then not Is_Access_Constant (T)
3146 and then Is_Access_Type (Etype (E))
3147 and then Is_Access_Constant (Etype (E))
3150 ("access to variable cannot be initialized "
3151 & "with an access-to-constant expression", E);
3154 if not Assignment_OK (N) then
3155 Check_Initialization (T, E);
3158 Check_Unset_Reference (E);
3160 -- If this is a variable, then set current value. If this is a
3161 -- declared constant of a scalar type with a static expression,
3162 -- indicate that it is always valid.
3164 if not Constant_Present (N) then
3165 if Compile_Time_Known_Value (E) then
3166 Set_Current_Value (Id, E);
3169 elsif Is_Scalar_Type (T)
3170 and then Is_OK_Static_Expression (E)
3172 Set_Is_Known_Valid (Id);
3175 -- Deal with setting of null flags
3177 if Is_Access_Type (T) then
3178 if Known_Non_Null (E) then
3179 Set_Is_Known_Non_Null (Id, True);
3180 elsif Known_Null (E)
3181 and then not Can_Never_Be_Null (Id)
3183 Set_Is_Known_Null (Id, True);
3187 -- Check incorrect use of dynamically tagged expressions.
3189 if Is_Tagged_Type (T) then
3190 Check_Dynamically_Tagged_Expression
3196 Apply_Scalar_Range_Check (E, T);
3197 Apply_Static_Length_Check (E, T);
3199 if Nkind (Original_Node (N)) = N_Object_Declaration
3200 and then Comes_From_Source (Original_Node (N))
3202 -- Only call test if needed
3204 and then Restriction_Check_Required (SPARK)
3205 and then not Is_SPARK_Initialization_Expr (E)
3207 Check_SPARK_Restriction
3208 ("initialization expression is not appropriate", E);
3212 -- If the No_Streams restriction is set, check that the type of the
3213 -- object is not, and does not contain, any subtype derived from
3214 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
3215 -- Has_Stream just for efficiency reasons. There is no point in
3216 -- spending time on a Has_Stream check if the restriction is not set.
3218 if Restriction_Check_Required (No_Streams) then
3219 if Has_Stream (T) then
3220 Check_Restriction (No_Streams, N);
3224 -- Deal with predicate check before we start to do major rewriting.
3225 -- it is OK to initialize and then check the initialized value, since
3226 -- the object goes out of scope if we get a predicate failure. Note
3227 -- that we do this in the analyzer and not the expander because the
3228 -- analyzer does some substantial rewriting in some cases.
3230 -- We need a predicate check if the type has predicates, and if either
3231 -- there is an initializing expression, or for default initialization
3232 -- when we have at least one case of an explicit default initial value.
3234 if not Suppress_Assignment_Checks (N)
3235 and then Present (Predicate_Function (T))
3239 Is_Partially_Initialized_Type (T, Include_Implicit => False))
3242 Make_Predicate_Check (T, New_Occurrence_Of (Id, Loc)));
3245 -- Case of unconstrained type
3247 if Is_Indefinite_Subtype (T) then
3249 -- Nothing to do in deferred constant case
3251 if Constant_Present (N) and then No (E) then
3254 -- Case of no initialization present
3257 if No_Initialization (N) then
3260 elsif Is_Class_Wide_Type (T) then
3262 ("initialization required in class-wide declaration ", N);
3266 ("unconstrained subtype not allowed (need initialization)",
3267 Object_Definition (N));
3269 if Is_Record_Type (T) and then Has_Discriminants (T) then
3271 ("\provide initial value or explicit discriminant values",
3272 Object_Definition (N));
3275 ("\or give default discriminant values for type&",
3276 Object_Definition (N), T);
3278 elsif Is_Array_Type (T) then
3280 ("\provide initial value or explicit array bounds",
3281 Object_Definition (N));
3285 -- Case of initialization present but in error. Set initial
3286 -- expression as absent (but do not make above complaints)
3288 elsif E = Error then
3289 Set_Expression (N, Empty);
3292 -- Case of initialization present
3295 -- Not allowed in Ada 83
3297 if not Constant_Present (N) then
3298 if Ada_Version = Ada_83
3299 and then Comes_From_Source (Object_Definition (N))
3302 ("(Ada 83) unconstrained variable not allowed",
3303 Object_Definition (N));
3307 -- Now we constrain the variable from the initializing expression
3309 -- If the expression is an aggregate, it has been expanded into
3310 -- individual assignments. Retrieve the actual type from the
3311 -- expanded construct.
3313 if Is_Array_Type (T)
3314 and then No_Initialization (N)
3315 and then Nkind (Original_Node (E)) = N_Aggregate
3319 -- In case of class-wide interface object declarations we delay
3320 -- the generation of the equivalent record type declarations until
3321 -- its expansion because there are cases in they are not required.
3323 elsif Is_Interface (T) then
3327 Expand_Subtype_From_Expr (N, T, Object_Definition (N), E);
3328 Act_T := Find_Type_Of_Object (Object_Definition (N), N);
3331 Set_Is_Constr_Subt_For_U_Nominal (Act_T);
3333 if Aliased_Present (N) then
3334 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
3337 Freeze_Before (N, Act_T);
3338 Freeze_Before (N, T);
3341 elsif Is_Array_Type (T)
3342 and then No_Initialization (N)
3343 and then Nkind (Original_Node (E)) = N_Aggregate
3345 if not Is_Entity_Name (Object_Definition (N)) then
3347 Check_Compile_Time_Size (Act_T);
3349 if Aliased_Present (N) then
3350 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
3354 -- When the given object definition and the aggregate are specified
3355 -- independently, and their lengths might differ do a length check.
3356 -- This cannot happen if the aggregate is of the form (others =>...)
3358 if not Is_Constrained (T) then
3361 elsif Nkind (E) = N_Raise_Constraint_Error then
3363 -- Aggregate is statically illegal. Place back in declaration
3365 Set_Expression (N, E);
3366 Set_No_Initialization (N, False);
3368 elsif T = Etype (E) then
3371 elsif Nkind (E) = N_Aggregate
3372 and then Present (Component_Associations (E))
3373 and then Present (Choices (First (Component_Associations (E))))
3374 and then Nkind (First
3375 (Choices (First (Component_Associations (E))))) = N_Others_Choice
3380 Apply_Length_Check (E, T);
3383 -- If the type is limited unconstrained with defaulted discriminants and
3384 -- there is no expression, then the object is constrained by the
3385 -- defaults, so it is worthwhile building the corresponding subtype.
3387 elsif (Is_Limited_Record (T) or else Is_Concurrent_Type (T))
3388 and then not Is_Constrained (T)
3389 and then Has_Discriminants (T)
3392 Act_T := Build_Default_Subtype (T, N);
3394 -- Ada 2005: a limited object may be initialized by means of an
3395 -- aggregate. If the type has default discriminants it has an
3396 -- unconstrained nominal type, Its actual subtype will be obtained
3397 -- from the aggregate, and not from the default discriminants.
3402 Rewrite (Object_Definition (N), New_Occurrence_Of (Act_T, Loc));
3404 elsif Present (Underlying_Type (T))
3405 and then not Is_Constrained (Underlying_Type (T))
3406 and then Has_Discriminants (Underlying_Type (T))
3407 and then Nkind (E) = N_Function_Call
3408 and then Constant_Present (N)
3410 -- The back-end has problems with constants of a discriminated type
3411 -- with defaults, if the initial value is a function call. We
3412 -- generate an intermediate temporary for the result of the call.
3413 -- It is unclear why this should make it acceptable to gcc. ???
3415 Remove_Side_Effects (E);
3417 -- If this is a constant declaration of an unconstrained type and
3418 -- the initialization is an aggregate, we can use the subtype of the
3419 -- aggregate for the declared entity because it is immutable.
3421 elsif not Is_Constrained (T)
3422 and then Has_Discriminants (T)
3423 and then Constant_Present (N)
3424 and then not Has_Unchecked_Union (T)
3425 and then Nkind (E) = N_Aggregate
3430 -- Check No_Wide_Characters restriction
3432 Check_Wide_Character_Restriction (T, Object_Definition (N));
3434 -- Indicate this is not set in source. Certainly true for constants, and
3435 -- true for variables so far (will be reset for a variable if and when
3436 -- we encounter a modification in the source).
3438 Set_Never_Set_In_Source (Id, True);
3440 -- Now establish the proper kind and type of the object
3442 if Constant_Present (N) then
3443 Set_Ekind (Id, E_Constant);
3444 Set_Is_True_Constant (Id, True);
3447 Set_Ekind (Id, E_Variable);
3449 -- A variable is set as shared passive if it appears in a shared
3450 -- passive package, and is at the outer level. This is not done for
3451 -- entities generated during expansion, because those are always
3452 -- manipulated locally.
3454 if Is_Shared_Passive (Current_Scope)
3455 and then Is_Library_Level_Entity (Id)
3456 and then Comes_From_Source (Id)
3458 Set_Is_Shared_Passive (Id);
3459 Check_Shared_Var (Id, T, N);
3462 -- Set Has_Initial_Value if initializing expression present. Note
3463 -- that if there is no initializing expression, we leave the state
3464 -- of this flag unchanged (usually it will be False, but notably in
3465 -- the case of exception choice variables, it will already be true).
3468 Set_Has_Initial_Value (Id, True);
3472 -- Initialize alignment and size and capture alignment setting
3474 Init_Alignment (Id);
3476 Set_Optimize_Alignment_Flags (Id);
3478 -- Deal with aliased case
3480 if Aliased_Present (N) then
3481 Set_Is_Aliased (Id);
3483 -- If the object is aliased and the type is unconstrained with
3484 -- defaulted discriminants and there is no expression, then the
3485 -- object is constrained by the defaults, so it is worthwhile
3486 -- building the corresponding subtype.
3488 -- Ada 2005 (AI-363): If the aliased object is discriminated and
3489 -- unconstrained, then only establish an actual subtype if the
3490 -- nominal subtype is indefinite. In definite cases the object is
3491 -- unconstrained in Ada 2005.
3494 and then Is_Record_Type (T)
3495 and then not Is_Constrained (T)
3496 and then Has_Discriminants (T)
3497 and then (Ada_Version < Ada_2005 or else Is_Indefinite_Subtype (T))
3499 Set_Actual_Subtype (Id, Build_Default_Subtype (T, N));
3503 -- Now we can set the type of the object
3505 Set_Etype (Id, Act_T);
3507 -- Deal with controlled types
3509 if Has_Controlled_Component (Etype (Id))
3510 or else Is_Controlled (Etype (Id))
3512 if not Is_Library_Level_Entity (Id) then
3513 Check_Restriction (No_Nested_Finalization, N);
3515 Validate_Controlled_Object (Id);
3518 -- Generate a warning when an initialization causes an obvious ABE
3519 -- violation. If the init expression is a simple aggregate there
3520 -- shouldn't be any initialize/adjust call generated. This will be
3521 -- true as soon as aggregates are built in place when possible.
3523 -- ??? at the moment we do not generate warnings for temporaries
3524 -- created for those aggregates although Program_Error might be
3525 -- generated if compiled with -gnato.
3527 if Is_Controlled (Etype (Id))
3528 and then Comes_From_Source (Id)
3531 BT : constant Entity_Id := Base_Type (Etype (Id));
3533 Implicit_Call : Entity_Id;
3534 pragma Warnings (Off, Implicit_Call);
3535 -- ??? what is this for (never referenced!)
3537 function Is_Aggr (N : Node_Id) return Boolean;
3538 -- Check that N is an aggregate
3544 function Is_Aggr (N : Node_Id) return Boolean is
3546 case Nkind (Original_Node (N)) is
3547 when N_Aggregate | N_Extension_Aggregate =>
3550 when N_Qualified_Expression |
3552 N_Unchecked_Type_Conversion =>
3553 return Is_Aggr (Expression (Original_Node (N)));
3561 -- If no underlying type, we already are in an error situation.
3562 -- Do not try to add a warning since we do not have access to
3565 if No (Underlying_Type (BT)) then
3566 Implicit_Call := Empty;
3568 -- A generic type does not have usable primitive operators.
3569 -- Initialization calls are built for instances.
3571 elsif Is_Generic_Type (BT) then
3572 Implicit_Call := Empty;
3574 -- If the init expression is not an aggregate, an adjust call
3575 -- will be generated
3577 elsif Present (E) and then not Is_Aggr (E) then
3578 Implicit_Call := Find_Prim_Op (BT, Name_Adjust);
3580 -- If no init expression and we are not in the deferred
3581 -- constant case, an Initialize call will be generated
3583 elsif No (E) and then not Constant_Present (N) then
3584 Implicit_Call := Find_Prim_Op (BT, Name_Initialize);
3587 Implicit_Call := Empty;
3593 if Has_Task (Etype (Id)) then
3594 Check_Restriction (No_Tasking, N);
3596 -- Deal with counting max tasks
3598 -- Nothing to do if inside a generic
3600 if Inside_A_Generic then
3603 -- If library level entity, then count tasks
3605 elsif Is_Library_Level_Entity (Id) then
3606 Check_Restriction (Max_Tasks, N, Count_Tasks (Etype (Id)));
3608 -- If not library level entity, then indicate we don't know max
3609 -- tasks and also check task hierarchy restriction and blocking
3610 -- operation (since starting a task is definitely blocking!)
3613 Check_Restriction (Max_Tasks, N);
3614 Check_Restriction (No_Task_Hierarchy, N);
3615 Check_Potentially_Blocking_Operation (N);
3618 -- A rather specialized test. If we see two tasks being declared
3619 -- of the same type in the same object declaration, and the task
3620 -- has an entry with an address clause, we know that program error
3621 -- will be raised at run time since we can't have two tasks with
3622 -- entries at the same address.
3624 if Is_Task_Type (Etype (Id)) and then More_Ids (N) then
3629 E := First_Entity (Etype (Id));
3630 while Present (E) loop
3631 if Ekind (E) = E_Entry
3632 and then Present (Get_Attribute_Definition_Clause
3633 (E, Attribute_Address))
3636 ("?more than one task with same entry address", N);
3638 ("\?Program_Error will be raised at run time", N);
3640 Make_Raise_Program_Error (Loc,
3641 Reason => PE_Duplicated_Entry_Address));
3651 -- Some simple constant-propagation: if the expression is a constant
3652 -- string initialized with a literal, share the literal. This avoids
3656 and then Is_Entity_Name (E)
3657 and then Ekind (Entity (E)) = E_Constant
3658 and then Base_Type (Etype (E)) = Standard_String
3661 Val : constant Node_Id := Constant_Value (Entity (E));
3664 and then Nkind (Val) = N_String_Literal
3666 Rewrite (E, New_Copy (Val));
3671 -- Another optimization: if the nominal subtype is unconstrained and
3672 -- the expression is a function call that returns an unconstrained
3673 -- type, rewrite the declaration as a renaming of the result of the
3674 -- call. The exceptions below are cases where the copy is expected,
3675 -- either by the back end (Aliased case) or by the semantics, as for
3676 -- initializing controlled types or copying tags for classwide types.
3679 and then Nkind (E) = N_Explicit_Dereference
3680 and then Nkind (Original_Node (E)) = N_Function_Call
3681 and then not Is_Library_Level_Entity (Id)
3682 and then not Is_Constrained (Underlying_Type (T))
3683 and then not Is_Aliased (Id)
3684 and then not Is_Class_Wide_Type (T)
3685 and then not Is_Controlled (T)
3686 and then not Has_Controlled_Component (Base_Type (T))
3687 and then Expander_Active
3690 Make_Object_Renaming_Declaration (Loc,
3691 Defining_Identifier => Id,
3692 Access_Definition => Empty,
3693 Subtype_Mark => New_Occurrence_Of
3694 (Base_Type (Etype (Id)), Loc),
3697 Set_Renamed_Object (Id, E);
3699 -- Force generation of debugging information for the constant and for
3700 -- the renamed function call.
3702 Set_Debug_Info_Needed (Id);
3703 Set_Debug_Info_Needed (Entity (Prefix (E)));
3706 if Present (Prev_Entity)
3707 and then Is_Frozen (Prev_Entity)
3708 and then not Error_Posted (Id)
3710 Error_Msg_N ("full constant declaration appears too late", N);
3713 Check_Eliminated (Id);
3715 -- Deal with setting In_Private_Part flag if in private part
3717 if Ekind (Scope (Id)) = E_Package
3718 and then In_Private_Part (Scope (Id))
3720 Set_In_Private_Part (Id);
3723 -- Check for violation of No_Local_Timing_Events
3725 if Restriction_Check_Required (No_Local_Timing_Events)
3726 and then not Is_Library_Level_Entity (Id)
3727 and then Is_RTE (Etype (Id), RE_Timing_Event)
3729 Check_Restriction (No_Local_Timing_Events, N);
3733 if Has_Aspects (N) then
3734 Analyze_Aspect_Specifications (N, Id);
3737 -- Generate 'I' xref for object initialization at definition, only used
3738 -- for the local xref section used in ALFA mode.
3740 if ALFA_Mode and then Present (Expression (Original_Node (N))) then
3741 Generate_Reference (Id, Id, 'I');
3743 end Analyze_Object_Declaration;
3745 ---------------------------
3746 -- Analyze_Others_Choice --
3747 ---------------------------
3749 -- Nothing to do for the others choice node itself, the semantic analysis
3750 -- of the others choice will occur as part of the processing of the parent
3752 procedure Analyze_Others_Choice (N : Node_Id) is
3753 pragma Warnings (Off, N);
3756 end Analyze_Others_Choice;
3758 -------------------------------------------
3759 -- Analyze_Private_Extension_Declaration --
3760 -------------------------------------------
3762 procedure Analyze_Private_Extension_Declaration (N : Node_Id) is
3763 T : constant Entity_Id := Defining_Identifier (N);
3764 Indic : constant Node_Id := Subtype_Indication (N);
3765 Parent_Type : Entity_Id;
3766 Parent_Base : Entity_Id;
3769 -- Ada 2005 (AI-251): Decorate all names in list of ancestor interfaces
3771 if Is_Non_Empty_List (Interface_List (N)) then
3777 Intf := First (Interface_List (N));
3778 while Present (Intf) loop
3779 T := Find_Type_Of_Subtype_Indic (Intf);
3781 Diagnose_Interface (Intf, T);
3787 Generate_Definition (T);
3789 -- For other than Ada 2012, just enter the name in the current scope
3791 if Ada_Version < Ada_2012 then
3794 -- Ada 2012 (AI05-0162): Enter the name in the current scope handling
3795 -- case of private type that completes an incomplete type.
3802 Prev := Find_Type_Name (N);
3804 pragma Assert (Prev = T
3805 or else (Ekind (Prev) = E_Incomplete_Type
3806 and then Present (Full_View (Prev))
3807 and then Full_View (Prev) = T));
3811 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
3812 Parent_Base := Base_Type (Parent_Type);
3814 if Parent_Type = Any_Type
3815 or else Etype (Parent_Type) = Any_Type
3817 Set_Ekind (T, Ekind (Parent_Type));
3818 Set_Etype (T, Any_Type);
3821 elsif not Is_Tagged_Type (Parent_Type) then
3823 ("parent of type extension must be a tagged type ", Indic);
3826 elsif Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
3827 Error_Msg_N ("premature derivation of incomplete type", Indic);
3830 elsif Is_Concurrent_Type (Parent_Type) then
3832 ("parent type of a private extension cannot be "
3833 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
3835 Set_Etype (T, Any_Type);
3836 Set_Ekind (T, E_Limited_Private_Type);
3837 Set_Private_Dependents (T, New_Elmt_List);
3838 Set_Error_Posted (T);
3842 -- Perhaps the parent type should be changed to the class-wide type's
3843 -- specific type in this case to prevent cascading errors ???
3845 if Is_Class_Wide_Type (Parent_Type) then
3847 ("parent of type extension must not be a class-wide type", Indic);
3851 if (not Is_Package_Or_Generic_Package (Current_Scope)
3852 and then Nkind (Parent (N)) /= N_Generic_Subprogram_Declaration)
3853 or else In_Private_Part (Current_Scope)
3856 Error_Msg_N ("invalid context for private extension", N);
3859 -- Set common attributes
3861 Set_Is_Pure (T, Is_Pure (Current_Scope));
3862 Set_Scope (T, Current_Scope);
3863 Set_Ekind (T, E_Record_Type_With_Private);
3864 Init_Size_Align (T);
3866 Set_Etype (T, Parent_Base);
3867 Set_Has_Task (T, Has_Task (Parent_Base));
3869 Set_Convention (T, Convention (Parent_Type));
3870 Set_First_Rep_Item (T, First_Rep_Item (Parent_Type));
3871 Set_Is_First_Subtype (T);
3872 Make_Class_Wide_Type (T);
3874 if Unknown_Discriminants_Present (N) then
3875 Set_Discriminant_Constraint (T, No_Elist);
3878 Build_Derived_Record_Type (N, Parent_Type, T);
3880 -- Propagate inherited invariant information. The new type has
3881 -- invariants, if the parent type has inheritable invariants,
3882 -- and these invariants can in turn be inherited.
3884 if Has_Inheritable_Invariants (Parent_Type) then
3885 Set_Has_Inheritable_Invariants (T);
3886 Set_Has_Invariants (T);
3889 -- Ada 2005 (AI-443): Synchronized private extension or a rewritten
3890 -- synchronized formal derived type.
3892 if Ada_Version >= Ada_2005
3893 and then Synchronized_Present (N)
3895 Set_Is_Limited_Record (T);
3897 -- Formal derived type case
3899 if Is_Generic_Type (T) then
3901 -- The parent must be a tagged limited type or a synchronized
3904 if (not Is_Tagged_Type (Parent_Type)
3905 or else not Is_Limited_Type (Parent_Type))
3907 (not Is_Interface (Parent_Type)
3908 or else not Is_Synchronized_Interface (Parent_Type))
3910 Error_Msg_NE ("parent type of & must be tagged limited " &
3911 "or synchronized", N, T);
3914 -- The progenitors (if any) must be limited or synchronized
3917 if Present (Interfaces (T)) then
3920 Iface_Elmt : Elmt_Id;
3923 Iface_Elmt := First_Elmt (Interfaces (T));
3924 while Present (Iface_Elmt) loop
3925 Iface := Node (Iface_Elmt);
3927 if not Is_Limited_Interface (Iface)
3928 and then not Is_Synchronized_Interface (Iface)
3930 Error_Msg_NE ("progenitor & must be limited " &
3931 "or synchronized", N, Iface);
3934 Next_Elmt (Iface_Elmt);
3939 -- Regular derived extension, the parent must be a limited or
3940 -- synchronized interface.
3943 if not Is_Interface (Parent_Type)
3944 or else (not Is_Limited_Interface (Parent_Type)
3946 not Is_Synchronized_Interface (Parent_Type))
3949 ("parent type of & must be limited interface", N, T);
3953 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
3954 -- extension with a synchronized parent must be explicitly declared
3955 -- synchronized, because the full view will be a synchronized type.
3956 -- This must be checked before the check for limited types below,
3957 -- to ensure that types declared limited are not allowed to extend
3958 -- synchronized interfaces.
3960 elsif Is_Interface (Parent_Type)
3961 and then Is_Synchronized_Interface (Parent_Type)
3962 and then not Synchronized_Present (N)
3965 ("private extension of& must be explicitly synchronized",
3968 elsif Limited_Present (N) then
3969 Set_Is_Limited_Record (T);
3971 if not Is_Limited_Type (Parent_Type)
3973 (not Is_Interface (Parent_Type)
3974 or else not Is_Limited_Interface (Parent_Type))
3976 Error_Msg_NE ("parent type& of limited extension must be limited",
3982 if Has_Aspects (N) then
3983 Analyze_Aspect_Specifications (N, T);
3985 end Analyze_Private_Extension_Declaration;
3987 ---------------------------------
3988 -- Analyze_Subtype_Declaration --
3989 ---------------------------------
3991 procedure Analyze_Subtype_Declaration
3993 Skip : Boolean := False)
3995 Id : constant Entity_Id := Defining_Identifier (N);
3997 R_Checks : Check_Result;
4000 Generate_Definition (Id);
4001 Set_Is_Pure (Id, Is_Pure (Current_Scope));
4002 Init_Size_Align (Id);
4004 -- The following guard condition on Enter_Name is to handle cases where
4005 -- the defining identifier has already been entered into the scope but
4006 -- the declaration as a whole needs to be analyzed.
4008 -- This case in particular happens for derived enumeration types. The
4009 -- derived enumeration type is processed as an inserted enumeration type
4010 -- declaration followed by a rewritten subtype declaration. The defining
4011 -- identifier, however, is entered into the name scope very early in the
4012 -- processing of the original type declaration and therefore needs to be
4013 -- avoided here, when the created subtype declaration is analyzed. (See
4014 -- Build_Derived_Types)
4016 -- This also happens when the full view of a private type is derived
4017 -- type with constraints. In this case the entity has been introduced
4018 -- in the private declaration.
4021 or else (Present (Etype (Id))
4022 and then (Is_Private_Type (Etype (Id))
4023 or else Is_Task_Type (Etype (Id))
4024 or else Is_Rewrite_Substitution (N)))
4032 T := Process_Subtype (Subtype_Indication (N), N, Id, 'P');
4034 -- Inherit common attributes
4036 Set_Is_Generic_Type (Id, Is_Generic_Type (Base_Type (T)));
4037 Set_Is_Volatile (Id, Is_Volatile (T));
4038 Set_Treat_As_Volatile (Id, Treat_As_Volatile (T));
4039 Set_Is_Atomic (Id, Is_Atomic (T));
4040 Set_Is_Ada_2005_Only (Id, Is_Ada_2005_Only (T));
4041 Set_Is_Ada_2012_Only (Id, Is_Ada_2012_Only (T));
4042 Set_Convention (Id, Convention (T));
4044 -- If ancestor has predicates then so does the subtype, and in addition
4045 -- we must delay the freeze to properly arrange predicate inheritance.
4047 -- The Ancestor_Type test is a big kludge, there seem to be cases in
4048 -- which T = ID, so the above tests and assignments do nothing???
4050 if Has_Predicates (T)
4051 or else (Present (Ancestor_Subtype (T))
4052 and then Has_Predicates (Ancestor_Subtype (T)))
4054 Set_Has_Predicates (Id);
4055 Set_Has_Delayed_Freeze (Id);
4058 -- Subtype of Boolean cannot have a constraint in SPARK
4060 if Is_Boolean_Type (T)
4061 and then Nkind (Subtype_Indication (N)) = N_Subtype_Indication
4063 Check_SPARK_Restriction
4064 ("subtype of Boolean cannot have constraint", N);
4067 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4069 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
4075 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint then
4076 One_Cstr := First (Constraints (Cstr));
4077 while Present (One_Cstr) loop
4079 -- Index or discriminant constraint in SPARK must be a
4083 Nkind_In (One_Cstr, N_Identifier, N_Expanded_Name)
4085 Check_SPARK_Restriction
4086 ("subtype mark required", One_Cstr);
4088 -- String subtype must have a lower bound of 1 in SPARK.
4089 -- Note that we do not need to test for the non-static case
4090 -- here, since that was already taken care of in
4091 -- Process_Range_Expr_In_Decl.
4093 elsif Base_Type (T) = Standard_String then
4094 Get_Index_Bounds (One_Cstr, Low, High);
4096 if Is_OK_Static_Expression (Low)
4097 and then Expr_Value (Low) /= 1
4099 Check_SPARK_Restriction
4100 ("String subtype must have lower bound of 1", N);
4110 -- In the case where there is no constraint given in the subtype
4111 -- indication, Process_Subtype just returns the Subtype_Mark, so its
4112 -- semantic attributes must be established here.
4114 if Nkind (Subtype_Indication (N)) /= N_Subtype_Indication then
4115 Set_Etype (Id, Base_Type (T));
4117 -- Subtype of unconstrained array without constraint is not allowed
4120 if Is_Array_Type (T)
4121 and then not Is_Constrained (T)
4123 Check_SPARK_Restriction
4124 ("subtype of unconstrained array must have constraint", N);
4129 Set_Ekind (Id, E_Array_Subtype);
4130 Copy_Array_Subtype_Attributes (Id, T);
4132 when Decimal_Fixed_Point_Kind =>
4133 Set_Ekind (Id, E_Decimal_Fixed_Point_Subtype);
4134 Set_Digits_Value (Id, Digits_Value (T));
4135 Set_Delta_Value (Id, Delta_Value (T));
4136 Set_Scale_Value (Id, Scale_Value (T));
4137 Set_Small_Value (Id, Small_Value (T));
4138 Set_Scalar_Range (Id, Scalar_Range (T));
4139 Set_Machine_Radix_10 (Id, Machine_Radix_10 (T));
4140 Set_Is_Constrained (Id, Is_Constrained (T));
4141 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4142 Set_RM_Size (Id, RM_Size (T));
4144 when Enumeration_Kind =>
4145 Set_Ekind (Id, E_Enumeration_Subtype);
4146 Set_First_Literal (Id, First_Literal (Base_Type (T)));
4147 Set_Scalar_Range (Id, Scalar_Range (T));
4148 Set_Is_Character_Type (Id, Is_Character_Type (T));
4149 Set_Is_Constrained (Id, Is_Constrained (T));
4150 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4151 Set_RM_Size (Id, RM_Size (T));
4153 when Ordinary_Fixed_Point_Kind =>
4154 Set_Ekind (Id, E_Ordinary_Fixed_Point_Subtype);
4155 Set_Scalar_Range (Id, Scalar_Range (T));
4156 Set_Small_Value (Id, Small_Value (T));
4157 Set_Delta_Value (Id, Delta_Value (T));
4158 Set_Is_Constrained (Id, Is_Constrained (T));
4159 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4160 Set_RM_Size (Id, RM_Size (T));
4163 Set_Ekind (Id, E_Floating_Point_Subtype);
4164 Set_Scalar_Range (Id, Scalar_Range (T));
4165 Set_Digits_Value (Id, Digits_Value (T));
4166 Set_Is_Constrained (Id, Is_Constrained (T));
4168 when Signed_Integer_Kind =>
4169 Set_Ekind (Id, E_Signed_Integer_Subtype);
4170 Set_Scalar_Range (Id, Scalar_Range (T));
4171 Set_Is_Constrained (Id, Is_Constrained (T));
4172 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4173 Set_RM_Size (Id, RM_Size (T));
4175 when Modular_Integer_Kind =>
4176 Set_Ekind (Id, E_Modular_Integer_Subtype);
4177 Set_Scalar_Range (Id, Scalar_Range (T));
4178 Set_Is_Constrained (Id, Is_Constrained (T));
4179 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4180 Set_RM_Size (Id, RM_Size (T));
4182 when Class_Wide_Kind =>
4183 Set_Ekind (Id, E_Class_Wide_Subtype);
4184 Set_First_Entity (Id, First_Entity (T));
4185 Set_Last_Entity (Id, Last_Entity (T));
4186 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4187 Set_Cloned_Subtype (Id, T);
4188 Set_Is_Tagged_Type (Id, True);
4189 Set_Has_Unknown_Discriminants
4192 if Ekind (T) = E_Class_Wide_Subtype then
4193 Set_Equivalent_Type (Id, Equivalent_Type (T));
4196 when E_Record_Type | E_Record_Subtype =>
4197 Set_Ekind (Id, E_Record_Subtype);
4199 if Ekind (T) = E_Record_Subtype
4200 and then Present (Cloned_Subtype (T))
4202 Set_Cloned_Subtype (Id, Cloned_Subtype (T));
4204 Set_Cloned_Subtype (Id, T);
4207 Set_First_Entity (Id, First_Entity (T));
4208 Set_Last_Entity (Id, Last_Entity (T));
4209 Set_Has_Discriminants (Id, Has_Discriminants (T));
4210 Set_Is_Constrained (Id, Is_Constrained (T));
4211 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4212 Set_Has_Unknown_Discriminants
4213 (Id, Has_Unknown_Discriminants (T));
4215 if Has_Discriminants (T) then
4216 Set_Discriminant_Constraint
4217 (Id, Discriminant_Constraint (T));
4218 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4220 elsif Has_Unknown_Discriminants (Id) then
4221 Set_Discriminant_Constraint (Id, No_Elist);
4224 if Is_Tagged_Type (T) then
4225 Set_Is_Tagged_Type (Id);
4226 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4227 Set_Direct_Primitive_Operations
4228 (Id, Direct_Primitive_Operations (T));
4229 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4231 if Is_Interface (T) then
4232 Set_Is_Interface (Id);
4233 Set_Is_Limited_Interface (Id, Is_Limited_Interface (T));
4237 when Private_Kind =>
4238 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4239 Set_Has_Discriminants (Id, Has_Discriminants (T));
4240 Set_Is_Constrained (Id, Is_Constrained (T));
4241 Set_First_Entity (Id, First_Entity (T));
4242 Set_Last_Entity (Id, Last_Entity (T));
4243 Set_Private_Dependents (Id, New_Elmt_List);
4244 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4245 Set_Has_Unknown_Discriminants
4246 (Id, Has_Unknown_Discriminants (T));
4247 Set_Known_To_Have_Preelab_Init
4248 (Id, Known_To_Have_Preelab_Init (T));
4250 if Is_Tagged_Type (T) then
4251 Set_Is_Tagged_Type (Id);
4252 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4253 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4254 Set_Direct_Primitive_Operations (Id,
4255 Direct_Primitive_Operations (T));
4258 -- In general the attributes of the subtype of a private type
4259 -- are the attributes of the partial view of parent. However,
4260 -- the full view may be a discriminated type, and the subtype
4261 -- must share the discriminant constraint to generate correct
4262 -- calls to initialization procedures.
4264 if Has_Discriminants (T) then
4265 Set_Discriminant_Constraint
4266 (Id, Discriminant_Constraint (T));
4267 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4269 elsif Present (Full_View (T))
4270 and then Has_Discriminants (Full_View (T))
4272 Set_Discriminant_Constraint
4273 (Id, Discriminant_Constraint (Full_View (T)));
4274 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4276 -- This would seem semantically correct, but apparently
4277 -- confuses the back-end. To be explained and checked with
4278 -- current version ???
4280 -- Set_Has_Discriminants (Id);
4283 Prepare_Private_Subtype_Completion (Id, N);
4286 Set_Ekind (Id, E_Access_Subtype);
4287 Set_Is_Constrained (Id, Is_Constrained (T));
4288 Set_Is_Access_Constant
4289 (Id, Is_Access_Constant (T));
4290 Set_Directly_Designated_Type
4291 (Id, Designated_Type (T));
4292 Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T));
4294 -- A Pure library_item must not contain the declaration of a
4295 -- named access type, except within a subprogram, generic
4296 -- subprogram, task unit, or protected unit, or if it has
4297 -- a specified Storage_Size of zero (RM05-10.2.1(15.4-15.5)).
4299 if Comes_From_Source (Id)
4300 and then In_Pure_Unit
4301 and then not In_Subprogram_Task_Protected_Unit
4302 and then not No_Pool_Assigned (Id)
4305 ("named access types not allowed in pure unit", N);
4308 when Concurrent_Kind =>
4309 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4310 Set_Corresponding_Record_Type (Id,
4311 Corresponding_Record_Type (T));
4312 Set_First_Entity (Id, First_Entity (T));
4313 Set_First_Private_Entity (Id, First_Private_Entity (T));
4314 Set_Has_Discriminants (Id, Has_Discriminants (T));
4315 Set_Is_Constrained (Id, Is_Constrained (T));
4316 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
4317 Set_Last_Entity (Id, Last_Entity (T));
4319 if Has_Discriminants (T) then
4320 Set_Discriminant_Constraint (Id,
4321 Discriminant_Constraint (T));
4322 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4325 when E_Incomplete_Type =>
4326 if Ada_Version >= Ada_2005 then
4327 Set_Ekind (Id, E_Incomplete_Subtype);
4329 -- Ada 2005 (AI-412): Decorate an incomplete subtype
4330 -- of an incomplete type visible through a limited
4333 if From_With_Type (T)
4334 and then Present (Non_Limited_View (T))
4336 Set_From_With_Type (Id);
4337 Set_Non_Limited_View (Id, Non_Limited_View (T));
4339 -- Ada 2005 (AI-412): Add the regular incomplete subtype
4340 -- to the private dependents of the original incomplete
4341 -- type for future transformation.
4344 Append_Elmt (Id, Private_Dependents (T));
4347 -- If the subtype name denotes an incomplete type an error
4348 -- was already reported by Process_Subtype.
4351 Set_Etype (Id, Any_Type);
4355 raise Program_Error;
4359 if Etype (Id) = Any_Type then
4363 -- Some common processing on all types
4365 Set_Size_Info (Id, T);
4366 Set_First_Rep_Item (Id, First_Rep_Item (T));
4370 Set_Is_Immediately_Visible (Id, True);
4371 Set_Depends_On_Private (Id, Has_Private_Component (T));
4372 Set_Is_Descendent_Of_Address (Id, Is_Descendent_Of_Address (T));
4374 if Is_Interface (T) then
4375 Set_Is_Interface (Id);
4378 if Present (Generic_Parent_Type (N))
4381 (Parent (Generic_Parent_Type (N))) /= N_Formal_Type_Declaration
4383 (Formal_Type_Definition (Parent (Generic_Parent_Type (N))))
4384 /= N_Formal_Private_Type_Definition)
4386 if Is_Tagged_Type (Id) then
4388 -- If this is a generic actual subtype for a synchronized type,
4389 -- the primitive operations are those of the corresponding record
4390 -- for which there is a separate subtype declaration.
4392 if Is_Concurrent_Type (Id) then
4394 elsif Is_Class_Wide_Type (Id) then
4395 Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T));
4397 Derive_Subprograms (Generic_Parent_Type (N), Id, T);
4400 elsif Scope (Etype (Id)) /= Standard_Standard then
4401 Derive_Subprograms (Generic_Parent_Type (N), Id);
4405 if Is_Private_Type (T)
4406 and then Present (Full_View (T))
4408 Conditional_Delay (Id, Full_View (T));
4410 -- The subtypes of components or subcomponents of protected types
4411 -- do not need freeze nodes, which would otherwise appear in the
4412 -- wrong scope (before the freeze node for the protected type). The
4413 -- proper subtypes are those of the subcomponents of the corresponding
4416 elsif Ekind (Scope (Id)) /= E_Protected_Type
4417 and then Present (Scope (Scope (Id))) -- error defense!
4418 and then Ekind (Scope (Scope (Id))) /= E_Protected_Type
4420 Conditional_Delay (Id, T);
4423 -- Check that Constraint_Error is raised for a scalar subtype indication
4424 -- when the lower or upper bound of a non-null range lies outside the
4425 -- range of the type mark.
4427 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4428 if Is_Scalar_Type (Etype (Id))
4429 and then Scalar_Range (Id) /=
4430 Scalar_Range (Etype (Subtype_Mark
4431 (Subtype_Indication (N))))
4435 Etype (Subtype_Mark (Subtype_Indication (N))));
4437 -- In the array case, check compatibility for each index
4439 elsif Is_Array_Type (Etype (Id))
4440 and then Present (First_Index (Id))
4442 -- This really should be a subprogram that finds the indications
4446 Subt_Index : Node_Id := First_Index (Id);
4447 Target_Index : Node_Id :=
4449 (Subtype_Mark (Subtype_Indication (N))));
4450 Has_Dyn_Chk : Boolean := Has_Dynamic_Range_Check (N);
4453 while Present (Subt_Index) loop
4454 if ((Nkind (Subt_Index) = N_Identifier
4455 and then Ekind (Entity (Subt_Index)) in Scalar_Kind)
4456 or else Nkind (Subt_Index) = N_Subtype_Indication)
4458 Nkind (Scalar_Range (Etype (Subt_Index))) = N_Range
4461 Target_Typ : constant Entity_Id :=
4462 Etype (Target_Index);
4466 (Scalar_Range (Etype (Subt_Index)),
4469 Defining_Identifier (N));
4471 -- Reset Has_Dynamic_Range_Check on the subtype to
4472 -- prevent elision of the index check due to a dynamic
4473 -- check generated for a preceding index (needed since
4474 -- Insert_Range_Checks tries to avoid generating
4475 -- redundant checks on a given declaration).
4477 Set_Has_Dynamic_Range_Check (N, False);
4483 Sloc (Defining_Identifier (N)));
4485 -- Record whether this index involved a dynamic check
4488 Has_Dyn_Chk or else Has_Dynamic_Range_Check (N);
4492 Next_Index (Subt_Index);
4493 Next_Index (Target_Index);
4496 -- Finally, mark whether the subtype involves dynamic checks
4498 Set_Has_Dynamic_Range_Check (N, Has_Dyn_Chk);
4503 -- Make sure that generic actual types are properly frozen. The subtype
4504 -- is marked as a generic actual type when the enclosing instance is
4505 -- analyzed, so here we identify the subtype from the tree structure.
4508 and then Is_Generic_Actual_Type (Id)
4509 and then In_Instance
4510 and then not Comes_From_Source (N)
4511 and then Nkind (Subtype_Indication (N)) /= N_Subtype_Indication
4512 and then Is_Frozen (T)
4514 Freeze_Before (N, Id);
4517 Set_Optimize_Alignment_Flags (Id);
4518 Check_Eliminated (Id);
4521 if Has_Aspects (N) then
4522 Analyze_Aspect_Specifications (N, Id);
4524 end Analyze_Subtype_Declaration;
4526 --------------------------------
4527 -- Analyze_Subtype_Indication --
4528 --------------------------------
4530 procedure Analyze_Subtype_Indication (N : Node_Id) is
4531 T : constant Entity_Id := Subtype_Mark (N);
4532 R : constant Node_Id := Range_Expression (Constraint (N));
4539 Set_Etype (N, Etype (R));
4540 Resolve (R, Entity (T));
4542 Set_Error_Posted (R);
4543 Set_Error_Posted (T);
4545 end Analyze_Subtype_Indication;
4547 --------------------------
4548 -- Analyze_Variant_Part --
4549 --------------------------
4551 procedure Analyze_Variant_Part (N : Node_Id) is
4553 procedure Non_Static_Choice_Error (Choice : Node_Id);
4554 -- Error routine invoked by the generic instantiation below when the
4555 -- variant part has a non static choice.
4557 procedure Process_Declarations (Variant : Node_Id);
4558 -- Analyzes all the declarations associated with a Variant. Needed by
4559 -- the generic instantiation below.
4561 package Variant_Choices_Processing is new
4562 Generic_Choices_Processing
4563 (Get_Alternatives => Variants,
4564 Get_Choices => Discrete_Choices,
4565 Process_Empty_Choice => No_OP,
4566 Process_Non_Static_Choice => Non_Static_Choice_Error,
4567 Process_Associated_Node => Process_Declarations);
4568 use Variant_Choices_Processing;
4569 -- Instantiation of the generic choice processing package
4571 -----------------------------
4572 -- Non_Static_Choice_Error --
4573 -----------------------------
4575 procedure Non_Static_Choice_Error (Choice : Node_Id) is
4577 Flag_Non_Static_Expr
4578 ("choice given in variant part is not static!", Choice);
4579 end Non_Static_Choice_Error;
4581 --------------------------
4582 -- Process_Declarations --
4583 --------------------------
4585 procedure Process_Declarations (Variant : Node_Id) is
4587 if not Null_Present (Component_List (Variant)) then
4588 Analyze_Declarations (Component_Items (Component_List (Variant)));
4590 if Present (Variant_Part (Component_List (Variant))) then
4591 Analyze (Variant_Part (Component_List (Variant)));
4594 end Process_Declarations;
4598 Discr_Name : Node_Id;
4599 Discr_Type : Entity_Id;
4601 Dont_Care : Boolean;
4602 Others_Present : Boolean := False;
4604 pragma Warnings (Off, Dont_Care);
4605 pragma Warnings (Off, Others_Present);
4606 -- We don't care about the assigned values of any of these
4608 -- Start of processing for Analyze_Variant_Part
4611 Discr_Name := Name (N);
4612 Analyze (Discr_Name);
4614 -- If Discr_Name bad, get out (prevent cascaded errors)
4616 if Etype (Discr_Name) = Any_Type then
4620 -- Check invalid discriminant in variant part
4622 if Ekind (Entity (Discr_Name)) /= E_Discriminant then
4623 Error_Msg_N ("invalid discriminant name in variant part", Discr_Name);
4626 Discr_Type := Etype (Entity (Discr_Name));
4628 if not Is_Discrete_Type (Discr_Type) then
4630 ("discriminant in a variant part must be of a discrete type",
4635 -- Call the instantiated Analyze_Choices which does the rest of the work
4637 Analyze_Choices (N, Discr_Type, Dont_Care, Others_Present);
4638 end Analyze_Variant_Part;
4640 ----------------------------
4641 -- Array_Type_Declaration --
4642 ----------------------------
4644 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is
4645 Component_Def : constant Node_Id := Component_Definition (Def);
4646 Component_Typ : constant Node_Id := Subtype_Indication (Component_Def);
4647 Element_Type : Entity_Id;
4648 Implicit_Base : Entity_Id;
4650 Related_Id : Entity_Id := Empty;
4652 P : constant Node_Id := Parent (Def);
4654 T_In_ALFA : Boolean := True;
4657 if Nkind (Def) = N_Constrained_Array_Definition then
4658 Index := First (Discrete_Subtype_Definitions (Def));
4660 Index := First (Subtype_Marks (Def));
4663 -- Find proper names for the implicit types which may be public. In case
4664 -- of anonymous arrays we use the name of the first object of that type
4668 Related_Id := Defining_Identifier (P);
4674 while Present (Index) loop
4677 if not Nkind_In (Index, N_Identifier, N_Expanded_Name) then
4678 Check_SPARK_Restriction ("subtype mark required", Index);
4681 if Present (Etype (Index))
4682 and then not Is_In_ALFA (Etype (Index))
4687 -- Add a subtype declaration for each index of private array type
4688 -- declaration whose etype is also private. For example:
4691 -- type Index is private;
4693 -- type Table is array (Index) of ...
4696 -- This is currently required by the expander for the internally
4697 -- generated equality subprogram of records with variant parts in
4698 -- which the etype of some component is such private type.
4700 if Ekind (Current_Scope) = E_Package
4701 and then In_Private_Part (Current_Scope)
4702 and then Has_Private_Declaration (Etype (Index))
4705 Loc : constant Source_Ptr := Sloc (Def);
4710 New_E := Make_Temporary (Loc, 'T');
4711 Set_Is_Internal (New_E);
4714 Make_Subtype_Declaration (Loc,
4715 Defining_Identifier => New_E,
4716 Subtype_Indication =>
4717 New_Occurrence_Of (Etype (Index), Loc));
4719 Insert_Before (Parent (Def), Decl);
4721 Set_Etype (Index, New_E);
4723 -- If the index is a range the Entity attribute is not
4724 -- available. Example:
4727 -- type T is private;
4729 -- type T is new Natural;
4730 -- Table : array (T(1) .. T(10)) of Boolean;
4733 if Nkind (Index) /= N_Range then
4734 Set_Entity (Index, New_E);
4739 Make_Index (Index, P, Related_Id, Nb_Index);
4741 -- Check error of subtype with predicate for index type
4743 Bad_Predicated_Subtype_Use
4744 ("subtype& has predicate, not allowed as index subtype",
4745 Index, Etype (Index));
4747 -- Move to next index
4750 Nb_Index := Nb_Index + 1;
4753 -- Process subtype indication if one is present
4755 if Present (Component_Typ) then
4756 Element_Type := Process_Subtype (Component_Typ, P, Related_Id, 'C');
4758 if not Nkind_In (Component_Typ, N_Identifier, N_Expanded_Name) then
4759 Check_SPARK_Restriction ("subtype mark required", Component_Typ);
4762 if Present (Element_Type)
4763 and then not Is_In_ALFA (Element_Type)
4768 -- Ada 2005 (AI-230): Access Definition case
4770 else pragma Assert (Present (Access_Definition (Component_Def)));
4774 -- Indicate that the anonymous access type is created by the
4775 -- array type declaration.
4777 Element_Type := Access_Definition
4779 N => Access_Definition (Component_Def));
4780 Set_Is_Local_Anonymous_Access (Element_Type);
4782 -- Propagate the parent. This field is needed if we have to generate
4783 -- the master_id associated with an anonymous access to task type
4784 -- component (see Expand_N_Full_Type_Declaration.Build_Master)
4786 Set_Parent (Element_Type, Parent (T));
4788 -- Ada 2005 (AI-230): In case of components that are anonymous access
4789 -- types the level of accessibility depends on the enclosing type
4792 Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230)
4794 -- Ada 2005 (AI-254)
4797 CD : constant Node_Id :=
4798 Access_To_Subprogram_Definition
4799 (Access_Definition (Component_Def));
4801 if Present (CD) and then Protected_Present (CD) then
4803 Replace_Anonymous_Access_To_Protected_Subprogram (Def);
4808 -- Constrained array case
4811 T := Create_Itype (E_Void, P, Related_Id, 'T');
4814 if Nkind (Def) = N_Constrained_Array_Definition then
4816 -- Establish Implicit_Base as unconstrained base type
4818 Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B');
4820 Set_Etype (Implicit_Base, Implicit_Base);
4821 Set_Scope (Implicit_Base, Current_Scope);
4822 Set_Has_Delayed_Freeze (Implicit_Base);
4824 -- The constrained array type is a subtype of the unconstrained one
4826 Set_Ekind (T, E_Array_Subtype);
4827 Init_Size_Align (T);
4828 Set_Etype (T, Implicit_Base);
4829 Set_Scope (T, Current_Scope);
4830 Set_Is_Constrained (T, True);
4831 Set_First_Index (T, First (Discrete_Subtype_Definitions (Def)));
4832 Set_Has_Delayed_Freeze (T);
4834 -- Complete setup of implicit base type
4836 Set_First_Index (Implicit_Base, First_Index (T));
4837 Set_Component_Type (Implicit_Base, Element_Type);
4838 Set_Has_Task (Implicit_Base, Has_Task (Element_Type));
4839 Set_Component_Size (Implicit_Base, Uint_0);
4840 Set_Packed_Array_Type (Implicit_Base, Empty);
4841 Set_Has_Controlled_Component
4842 (Implicit_Base, Has_Controlled_Component
4844 or else Is_Controlled
4846 Set_Finalize_Storage_Only
4847 (Implicit_Base, Finalize_Storage_Only
4850 -- Final check for static bounds on array
4852 if not Has_Static_Array_Bounds (T) then
4856 -- Unconstrained array case
4859 Set_Ekind (T, E_Array_Type);
4860 Init_Size_Align (T);
4862 Set_Scope (T, Current_Scope);
4863 Set_Component_Size (T, Uint_0);
4864 Set_Is_Constrained (T, False);
4865 Set_First_Index (T, First (Subtype_Marks (Def)));
4866 Set_Has_Delayed_Freeze (T, True);
4867 Set_Has_Task (T, Has_Task (Element_Type));
4868 Set_Has_Controlled_Component (T, Has_Controlled_Component
4871 Is_Controlled (Element_Type));
4872 Set_Finalize_Storage_Only (T, Finalize_Storage_Only
4876 -- Common attributes for both cases
4878 Set_Component_Type (Base_Type (T), Element_Type);
4879 Set_Packed_Array_Type (T, Empty);
4880 Set_Is_In_ALFA (T, T_In_ALFA);
4882 if Aliased_Present (Component_Definition (Def)) then
4883 Check_SPARK_Restriction
4884 ("aliased is not allowed", Component_Definition (Def));
4885 Set_Has_Aliased_Components (Etype (T));
4888 -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the
4889 -- array type to ensure that objects of this type are initialized.
4891 if Ada_Version >= Ada_2005
4892 and then Can_Never_Be_Null (Element_Type)
4894 Set_Can_Never_Be_Null (T);
4896 if Null_Exclusion_Present (Component_Definition (Def))
4898 -- No need to check itypes because in their case this check was
4899 -- done at their point of creation
4901 and then not Is_Itype (Element_Type)
4904 ("`NOT NULL` not allowed (null already excluded)",
4905 Subtype_Indication (Component_Definition (Def)));
4909 Priv := Private_Component (Element_Type);
4911 if Present (Priv) then
4913 -- Check for circular definitions
4915 if Priv = Any_Type then
4916 Set_Component_Type (Etype (T), Any_Type);
4918 -- There is a gap in the visibility of operations on the composite
4919 -- type only if the component type is defined in a different scope.
4921 elsif Scope (Priv) = Current_Scope then
4924 elsif Is_Limited_Type (Priv) then
4925 Set_Is_Limited_Composite (Etype (T));
4926 Set_Is_Limited_Composite (T);
4928 Set_Is_Private_Composite (Etype (T));
4929 Set_Is_Private_Composite (T);
4933 -- A syntax error in the declaration itself may lead to an empty index
4934 -- list, in which case do a minimal patch.
4936 if No (First_Index (T)) then
4937 Error_Msg_N ("missing index definition in array type declaration", T);
4940 Indexes : constant List_Id :=
4941 New_List (New_Occurrence_Of (Any_Id, Sloc (T)));
4943 Set_Discrete_Subtype_Definitions (Def, Indexes);
4944 Set_First_Index (T, First (Indexes));
4949 -- Create a concatenation operator for the new type. Internal array
4950 -- types created for packed entities do not need such, they are
4951 -- compatible with the user-defined type.
4953 if Number_Dimensions (T) = 1
4954 and then not Is_Packed_Array_Type (T)
4956 New_Concatenation_Op (T);
4959 -- In the case of an unconstrained array the parser has already verified
4960 -- that all the indexes are unconstrained but we still need to make sure
4961 -- that the element type is constrained.
4963 if Is_Indefinite_Subtype (Element_Type) then
4965 ("unconstrained element type in array declaration",
4966 Subtype_Indication (Component_Def));
4968 elsif Is_Abstract_Type (Element_Type) then
4970 ("the type of a component cannot be abstract",
4971 Subtype_Indication (Component_Def));
4973 end Array_Type_Declaration;
4975 ------------------------------------------------------
4976 -- Replace_Anonymous_Access_To_Protected_Subprogram --
4977 ------------------------------------------------------
4979 function Replace_Anonymous_Access_To_Protected_Subprogram
4980 (N : Node_Id) return Entity_Id
4982 Loc : constant Source_Ptr := Sloc (N);
4984 Curr_Scope : constant Scope_Stack_Entry :=
4985 Scope_Stack.Table (Scope_Stack.Last);
4987 Anon : constant Entity_Id := Make_Temporary (Loc, 'S');
4994 Set_Is_Internal (Anon);
4997 when N_Component_Declaration |
4998 N_Unconstrained_Array_Definition |
4999 N_Constrained_Array_Definition =>
5000 Comp := Component_Definition (N);
5001 Acc := Access_Definition (Comp);
5003 when N_Discriminant_Specification =>
5004 Comp := Discriminant_Type (N);
5007 when N_Parameter_Specification =>
5008 Comp := Parameter_Type (N);
5011 when N_Access_Function_Definition =>
5012 Comp := Result_Definition (N);
5015 when N_Object_Declaration =>
5016 Comp := Object_Definition (N);
5019 when N_Function_Specification =>
5020 Comp := Result_Definition (N);
5024 raise Program_Error;
5027 Decl := Make_Full_Type_Declaration (Loc,
5028 Defining_Identifier => Anon,
5030 Copy_Separate_Tree (Access_To_Subprogram_Definition (Acc)));
5032 Mark_Rewrite_Insertion (Decl);
5034 -- Insert the new declaration in the nearest enclosing scope. If the
5035 -- node is a body and N is its return type, the declaration belongs in
5036 -- the enclosing scope.
5040 if Nkind (P) = N_Subprogram_Body
5041 and then Nkind (N) = N_Function_Specification
5046 while Present (P) and then not Has_Declarations (P) loop
5050 pragma Assert (Present (P));
5052 if Nkind (P) = N_Package_Specification then
5053 Prepend (Decl, Visible_Declarations (P));
5055 Prepend (Decl, Declarations (P));
5058 -- Replace the anonymous type with an occurrence of the new declaration.
5059 -- In all cases the rewritten node does not have the null-exclusion
5060 -- attribute because (if present) it was already inherited by the
5061 -- anonymous entity (Anon). Thus, in case of components we do not
5062 -- inherit this attribute.
5064 if Nkind (N) = N_Parameter_Specification then
5065 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5066 Set_Etype (Defining_Identifier (N), Anon);
5067 Set_Null_Exclusion_Present (N, False);
5069 elsif Nkind (N) = N_Object_Declaration then
5070 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5071 Set_Etype (Defining_Identifier (N), Anon);
5073 elsif Nkind (N) = N_Access_Function_Definition then
5074 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5076 elsif Nkind (N) = N_Function_Specification then
5077 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5078 Set_Etype (Defining_Unit_Name (N), Anon);
5082 Make_Component_Definition (Loc,
5083 Subtype_Indication => New_Occurrence_Of (Anon, Loc)));
5086 Mark_Rewrite_Insertion (Comp);
5088 if Nkind_In (N, N_Object_Declaration, N_Access_Function_Definition) then
5092 -- Temporarily remove the current scope (record or subprogram) from
5093 -- the stack to add the new declarations to the enclosing scope.
5095 Scope_Stack.Decrement_Last;
5097 Set_Is_Itype (Anon);
5098 Scope_Stack.Append (Curr_Scope);
5101 Set_Ekind (Anon, E_Anonymous_Access_Protected_Subprogram_Type);
5102 Set_Can_Use_Internal_Rep (Anon, not Always_Compatible_Rep_On_Target);
5104 end Replace_Anonymous_Access_To_Protected_Subprogram;
5106 -------------------------------
5107 -- Build_Derived_Access_Type --
5108 -------------------------------
5110 procedure Build_Derived_Access_Type
5112 Parent_Type : Entity_Id;
5113 Derived_Type : Entity_Id)
5115 S : constant Node_Id := Subtype_Indication (Type_Definition (N));
5117 Desig_Type : Entity_Id;
5119 Discr_Con_Elist : Elist_Id;
5120 Discr_Con_El : Elmt_Id;
5124 -- Set the designated type so it is available in case this is an access
5125 -- to a self-referential type, e.g. a standard list type with a next
5126 -- pointer. Will be reset after subtype is built.
5128 Set_Directly_Designated_Type
5129 (Derived_Type, Designated_Type (Parent_Type));
5131 Subt := Process_Subtype (S, N);
5133 if Nkind (S) /= N_Subtype_Indication
5134 and then Subt /= Base_Type (Subt)
5136 Set_Ekind (Derived_Type, E_Access_Subtype);
5139 if Ekind (Derived_Type) = E_Access_Subtype then
5141 Pbase : constant Entity_Id := Base_Type (Parent_Type);
5142 Ibase : constant Entity_Id :=
5143 Create_Itype (Ekind (Pbase), N, Derived_Type, 'B');
5144 Svg_Chars : constant Name_Id := Chars (Ibase);
5145 Svg_Next_E : constant Entity_Id := Next_Entity (Ibase);
5148 Copy_Node (Pbase, Ibase);
5150 Set_Chars (Ibase, Svg_Chars);
5151 Set_Next_Entity (Ibase, Svg_Next_E);
5152 Set_Sloc (Ibase, Sloc (Derived_Type));
5153 Set_Scope (Ibase, Scope (Derived_Type));
5154 Set_Freeze_Node (Ibase, Empty);
5155 Set_Is_Frozen (Ibase, False);
5156 Set_Comes_From_Source (Ibase, False);
5157 Set_Is_First_Subtype (Ibase, False);
5159 Set_Etype (Ibase, Pbase);
5160 Set_Etype (Derived_Type, Ibase);
5164 Set_Directly_Designated_Type
5165 (Derived_Type, Designated_Type (Subt));
5167 Set_Is_Constrained (Derived_Type, Is_Constrained (Subt));
5168 Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type));
5169 Set_Size_Info (Derived_Type, Parent_Type);
5170 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
5171 Set_Depends_On_Private (Derived_Type,
5172 Has_Private_Component (Derived_Type));
5173 Conditional_Delay (Derived_Type, Subt);
5175 -- Ada 2005 (AI-231): Set the null-exclusion attribute, and verify
5176 -- that it is not redundant.
5178 if Null_Exclusion_Present (Type_Definition (N)) then
5179 Set_Can_Never_Be_Null (Derived_Type);
5181 if Can_Never_Be_Null (Parent_Type)
5185 ("`NOT NULL` not allowed (& already excludes null)",
5189 elsif Can_Never_Be_Null (Parent_Type) then
5190 Set_Can_Never_Be_Null (Derived_Type);
5193 -- Note: we do not copy the Storage_Size_Variable, since we always go to
5194 -- the root type for this information.
5196 -- Apply range checks to discriminants for derived record case
5197 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
5199 Desig_Type := Designated_Type (Derived_Type);
5200 if Is_Composite_Type (Desig_Type)
5201 and then (not Is_Array_Type (Desig_Type))
5202 and then Has_Discriminants (Desig_Type)
5203 and then Base_Type (Desig_Type) /= Desig_Type
5205 Discr_Con_Elist := Discriminant_Constraint (Desig_Type);
5206 Discr_Con_El := First_Elmt (Discr_Con_Elist);
5208 Discr := First_Discriminant (Base_Type (Desig_Type));
5209 while Present (Discr_Con_El) loop
5210 Apply_Range_Check (Node (Discr_Con_El), Etype (Discr));
5211 Next_Elmt (Discr_Con_El);
5212 Next_Discriminant (Discr);
5215 end Build_Derived_Access_Type;
5217 ------------------------------
5218 -- Build_Derived_Array_Type --
5219 ------------------------------
5221 procedure Build_Derived_Array_Type
5223 Parent_Type : Entity_Id;
5224 Derived_Type : Entity_Id)
5226 Loc : constant Source_Ptr := Sloc (N);
5227 Tdef : constant Node_Id := Type_Definition (N);
5228 Indic : constant Node_Id := Subtype_Indication (Tdef);
5229 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
5230 Implicit_Base : Entity_Id;
5231 New_Indic : Node_Id;
5233 procedure Make_Implicit_Base;
5234 -- If the parent subtype is constrained, the derived type is a subtype
5235 -- of an implicit base type derived from the parent base.
5237 ------------------------
5238 -- Make_Implicit_Base --
5239 ------------------------
5241 procedure Make_Implicit_Base is
5244 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
5246 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
5247 Set_Etype (Implicit_Base, Parent_Base);
5249 Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base);
5250 Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base);
5252 Set_Has_Delayed_Freeze (Implicit_Base, True);
5253 end Make_Implicit_Base;
5255 -- Start of processing for Build_Derived_Array_Type
5258 if not Is_Constrained (Parent_Type) then
5259 if Nkind (Indic) /= N_Subtype_Indication then
5260 Set_Ekind (Derived_Type, E_Array_Type);
5262 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
5263 Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type);
5265 Set_Has_Delayed_Freeze (Derived_Type, True);
5269 Set_Etype (Derived_Type, Implicit_Base);
5272 Make_Subtype_Declaration (Loc,
5273 Defining_Identifier => Derived_Type,
5274 Subtype_Indication =>
5275 Make_Subtype_Indication (Loc,
5276 Subtype_Mark => New_Reference_To (Implicit_Base, Loc),
5277 Constraint => Constraint (Indic)));
5279 Rewrite (N, New_Indic);
5284 if Nkind (Indic) /= N_Subtype_Indication then
5287 Set_Ekind (Derived_Type, Ekind (Parent_Type));
5288 Set_Etype (Derived_Type, Implicit_Base);
5289 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
5292 Error_Msg_N ("illegal constraint on constrained type", Indic);
5296 -- If parent type is not a derived type itself, and is declared in
5297 -- closed scope (e.g. a subprogram), then we must explicitly introduce
5298 -- the new type's concatenation operator since Derive_Subprograms
5299 -- will not inherit the parent's operator. If the parent type is
5300 -- unconstrained, the operator is of the unconstrained base type.
5302 if Number_Dimensions (Parent_Type) = 1
5303 and then not Is_Limited_Type (Parent_Type)
5304 and then not Is_Derived_Type (Parent_Type)
5305 and then not Is_Package_Or_Generic_Package
5306 (Scope (Base_Type (Parent_Type)))
5308 if not Is_Constrained (Parent_Type)
5309 and then Is_Constrained (Derived_Type)
5311 New_Concatenation_Op (Implicit_Base);
5313 New_Concatenation_Op (Derived_Type);
5316 end Build_Derived_Array_Type;
5318 -----------------------------------
5319 -- Build_Derived_Concurrent_Type --
5320 -----------------------------------
5322 procedure Build_Derived_Concurrent_Type
5324 Parent_Type : Entity_Id;
5325 Derived_Type : Entity_Id)
5327 Loc : constant Source_Ptr := Sloc (N);
5329 Corr_Record : constant Entity_Id := Make_Temporary (Loc, 'C');
5330 Corr_Decl : Node_Id;
5331 Corr_Decl_Needed : Boolean;
5332 -- If the derived type has fewer discriminants than its parent, the
5333 -- corresponding record is also a derived type, in order to account for
5334 -- the bound discriminants. We create a full type declaration for it in
5337 Constraint_Present : constant Boolean :=
5338 Nkind (Subtype_Indication (Type_Definition (N))) =
5339 N_Subtype_Indication;
5341 D_Constraint : Node_Id;
5342 New_Constraint : Elist_Id;
5343 Old_Disc : Entity_Id;
5344 New_Disc : Entity_Id;
5348 Set_Stored_Constraint (Derived_Type, No_Elist);
5349 Corr_Decl_Needed := False;
5352 if Present (Discriminant_Specifications (N))
5353 and then Constraint_Present
5355 Old_Disc := First_Discriminant (Parent_Type);
5356 New_Disc := First (Discriminant_Specifications (N));
5357 while Present (New_Disc) and then Present (Old_Disc) loop
5358 Next_Discriminant (Old_Disc);
5363 if Present (Old_Disc) and then Expander_Active then
5365 -- The new type has fewer discriminants, so we need to create a new
5366 -- corresponding record, which is derived from the corresponding
5367 -- record of the parent, and has a stored constraint that captures
5368 -- the values of the discriminant constraints. The corresponding
5369 -- record is needed only if expander is active and code generation is
5372 -- The type declaration for the derived corresponding record has the
5373 -- same discriminant part and constraints as the current declaration.
5374 -- Copy the unanalyzed tree to build declaration.
5376 Corr_Decl_Needed := True;
5377 New_N := Copy_Separate_Tree (N);
5380 Make_Full_Type_Declaration (Loc,
5381 Defining_Identifier => Corr_Record,
5382 Discriminant_Specifications =>
5383 Discriminant_Specifications (New_N),
5385 Make_Derived_Type_Definition (Loc,
5386 Subtype_Indication =>
5387 Make_Subtype_Indication (Loc,
5390 (Corresponding_Record_Type (Parent_Type), Loc),
5393 (Subtype_Indication (Type_Definition (New_N))))));
5396 -- Copy Storage_Size and Relative_Deadline variables if task case
5398 if Is_Task_Type (Parent_Type) then
5399 Set_Storage_Size_Variable (Derived_Type,
5400 Storage_Size_Variable (Parent_Type));
5401 Set_Relative_Deadline_Variable (Derived_Type,
5402 Relative_Deadline_Variable (Parent_Type));
5405 if Present (Discriminant_Specifications (N)) then
5406 Push_Scope (Derived_Type);
5407 Check_Or_Process_Discriminants (N, Derived_Type);
5409 if Constraint_Present then
5411 Expand_To_Stored_Constraint
5413 Build_Discriminant_Constraints
5415 Subtype_Indication (Type_Definition (N)), True));
5420 elsif Constraint_Present then
5422 -- Build constrained subtype and derive from it
5425 Loc : constant Source_Ptr := Sloc (N);
5426 Anon : constant Entity_Id :=
5427 Make_Defining_Identifier (Loc,
5428 Chars => New_External_Name (Chars (Derived_Type), 'T'));
5433 Make_Subtype_Declaration (Loc,
5434 Defining_Identifier => Anon,
5435 Subtype_Indication =>
5436 Subtype_Indication (Type_Definition (N)));
5437 Insert_Before (N, Decl);
5440 Rewrite (Subtype_Indication (Type_Definition (N)),
5441 New_Occurrence_Of (Anon, Loc));
5442 Set_Analyzed (Derived_Type, False);
5448 -- By default, operations and private data are inherited from parent.
5449 -- However, in the presence of bound discriminants, a new corresponding
5450 -- record will be created, see below.
5452 Set_Has_Discriminants
5453 (Derived_Type, Has_Discriminants (Parent_Type));
5454 Set_Corresponding_Record_Type
5455 (Derived_Type, Corresponding_Record_Type (Parent_Type));
5457 -- Is_Constrained is set according the parent subtype, but is set to
5458 -- False if the derived type is declared with new discriminants.
5462 (Is_Constrained (Parent_Type) or else Constraint_Present)
5463 and then not Present (Discriminant_Specifications (N)));
5465 if Constraint_Present then
5466 if not Has_Discriminants (Parent_Type) then
5467 Error_Msg_N ("untagged parent must have discriminants", N);
5469 elsif Present (Discriminant_Specifications (N)) then
5471 -- Verify that new discriminants are used to constrain old ones
5476 (Constraint (Subtype_Indication (Type_Definition (N)))));
5478 Old_Disc := First_Discriminant (Parent_Type);
5480 while Present (D_Constraint) loop
5481 if Nkind (D_Constraint) /= N_Discriminant_Association then
5483 -- Positional constraint. If it is a reference to a new
5484 -- discriminant, it constrains the corresponding old one.
5486 if Nkind (D_Constraint) = N_Identifier then
5487 New_Disc := First_Discriminant (Derived_Type);
5488 while Present (New_Disc) loop
5489 exit when Chars (New_Disc) = Chars (D_Constraint);
5490 Next_Discriminant (New_Disc);
5493 if Present (New_Disc) then
5494 Set_Corresponding_Discriminant (New_Disc, Old_Disc);
5498 Next_Discriminant (Old_Disc);
5500 -- if this is a named constraint, search by name for the old
5501 -- discriminants constrained by the new one.
5503 elsif Nkind (Expression (D_Constraint)) = N_Identifier then
5505 -- Find new discriminant with that name
5507 New_Disc := First_Discriminant (Derived_Type);
5508 while Present (New_Disc) loop
5510 Chars (New_Disc) = Chars (Expression (D_Constraint));
5511 Next_Discriminant (New_Disc);
5514 if Present (New_Disc) then
5516 -- Verify that new discriminant renames some discriminant
5517 -- of the parent type, and associate the new discriminant
5518 -- with one or more old ones that it renames.
5524 Selector := First (Selector_Names (D_Constraint));
5525 while Present (Selector) loop
5526 Old_Disc := First_Discriminant (Parent_Type);
5527 while Present (Old_Disc) loop
5528 exit when Chars (Old_Disc) = Chars (Selector);
5529 Next_Discriminant (Old_Disc);
5532 if Present (Old_Disc) then
5533 Set_Corresponding_Discriminant
5534 (New_Disc, Old_Disc);
5543 Next (D_Constraint);
5546 New_Disc := First_Discriminant (Derived_Type);
5547 while Present (New_Disc) loop
5548 if No (Corresponding_Discriminant (New_Disc)) then
5550 ("new discriminant& must constrain old one", N, New_Disc);
5553 Subtypes_Statically_Compatible
5555 Etype (Corresponding_Discriminant (New_Disc)))
5558 ("& not statically compatible with parent discriminant",
5562 Next_Discriminant (New_Disc);
5566 elsif Present (Discriminant_Specifications (N)) then
5568 ("missing discriminant constraint in untagged derivation", N);
5571 -- The entity chain of the derived type includes the new discriminants
5572 -- but shares operations with the parent.
5574 if Present (Discriminant_Specifications (N)) then
5575 Old_Disc := First_Discriminant (Parent_Type);
5576 while Present (Old_Disc) loop
5577 if No (Next_Entity (Old_Disc))
5578 or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant
5581 (Last_Entity (Derived_Type), Next_Entity (Old_Disc));
5585 Next_Discriminant (Old_Disc);
5589 Set_First_Entity (Derived_Type, First_Entity (Parent_Type));
5590 if Has_Discriminants (Parent_Type) then
5591 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
5592 Set_Discriminant_Constraint (
5593 Derived_Type, Discriminant_Constraint (Parent_Type));
5597 Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type));
5599 Set_Has_Completion (Derived_Type);
5601 if Corr_Decl_Needed then
5602 Set_Stored_Constraint (Derived_Type, New_Constraint);
5603 Insert_After (N, Corr_Decl);
5604 Analyze (Corr_Decl);
5605 Set_Corresponding_Record_Type (Derived_Type, Corr_Record);
5607 end Build_Derived_Concurrent_Type;
5609 ------------------------------------
5610 -- Build_Derived_Enumeration_Type --
5611 ------------------------------------
5613 procedure Build_Derived_Enumeration_Type
5615 Parent_Type : Entity_Id;
5616 Derived_Type : Entity_Id)
5618 Loc : constant Source_Ptr := Sloc (N);
5619 Def : constant Node_Id := Type_Definition (N);
5620 Indic : constant Node_Id := Subtype_Indication (Def);
5621 Implicit_Base : Entity_Id;
5622 Literal : Entity_Id;
5623 New_Lit : Entity_Id;
5624 Literals_List : List_Id;
5625 Type_Decl : Node_Id;
5627 Rang_Expr : Node_Id;
5630 -- Since types Standard.Character and Standard.[Wide_]Wide_Character do
5631 -- not have explicit literals lists we need to process types derived
5632 -- from them specially. This is handled by Derived_Standard_Character.
5633 -- If the parent type is a generic type, there are no literals either,
5634 -- and we construct the same skeletal representation as for the generic
5637 if Is_Standard_Character_Type (Parent_Type) then
5638 Derived_Standard_Character (N, Parent_Type, Derived_Type);
5640 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
5646 if Nkind (Indic) /= N_Subtype_Indication then
5648 Make_Attribute_Reference (Loc,
5649 Attribute_Name => Name_First,
5650 Prefix => New_Reference_To (Derived_Type, Loc));
5651 Set_Etype (Lo, Derived_Type);
5654 Make_Attribute_Reference (Loc,
5655 Attribute_Name => Name_Last,
5656 Prefix => New_Reference_To (Derived_Type, Loc));
5657 Set_Etype (Hi, Derived_Type);
5659 Set_Scalar_Range (Derived_Type,
5665 -- Analyze subtype indication and verify compatibility
5666 -- with parent type.
5668 if Base_Type (Process_Subtype (Indic, N)) /=
5669 Base_Type (Parent_Type)
5672 ("illegal constraint for formal discrete type", N);
5678 -- If a constraint is present, analyze the bounds to catch
5679 -- premature usage of the derived literals.
5681 if Nkind (Indic) = N_Subtype_Indication
5682 and then Nkind (Range_Expression (Constraint (Indic))) = N_Range
5684 Analyze (Low_Bound (Range_Expression (Constraint (Indic))));
5685 Analyze (High_Bound (Range_Expression (Constraint (Indic))));
5688 -- Introduce an implicit base type for the derived type even if there
5689 -- is no constraint attached to it, since this seems closer to the
5690 -- Ada semantics. Build a full type declaration tree for the derived
5691 -- type using the implicit base type as the defining identifier. The
5692 -- build a subtype declaration tree which applies the constraint (if
5693 -- any) have it replace the derived type declaration.
5695 Literal := First_Literal (Parent_Type);
5696 Literals_List := New_List;
5697 while Present (Literal)
5698 and then Ekind (Literal) = E_Enumeration_Literal
5700 -- Literals of the derived type have the same representation as
5701 -- those of the parent type, but this representation can be
5702 -- overridden by an explicit representation clause. Indicate
5703 -- that there is no explicit representation given yet. These
5704 -- derived literals are implicit operations of the new type,
5705 -- and can be overridden by explicit ones.
5707 if Nkind (Literal) = N_Defining_Character_Literal then
5709 Make_Defining_Character_Literal (Loc, Chars (Literal));
5711 New_Lit := Make_Defining_Identifier (Loc, Chars (Literal));
5714 Set_Ekind (New_Lit, E_Enumeration_Literal);
5715 Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal));
5716 Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal));
5717 Set_Enumeration_Rep_Expr (New_Lit, Empty);
5718 Set_Alias (New_Lit, Literal);
5719 Set_Is_Known_Valid (New_Lit, True);
5721 Append (New_Lit, Literals_List);
5722 Next_Literal (Literal);
5726 Make_Defining_Identifier (Sloc (Derived_Type),
5727 Chars => New_External_Name (Chars (Derived_Type), 'B'));
5729 -- Indicate the proper nature of the derived type. This must be done
5730 -- before analysis of the literals, to recognize cases when a literal
5731 -- may be hidden by a previous explicit function definition (cf.
5734 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
5735 Set_Etype (Derived_Type, Implicit_Base);
5738 Make_Full_Type_Declaration (Loc,
5739 Defining_Identifier => Implicit_Base,
5740 Discriminant_Specifications => No_List,
5742 Make_Enumeration_Type_Definition (Loc, Literals_List));
5744 Mark_Rewrite_Insertion (Type_Decl);
5745 Insert_Before (N, Type_Decl);
5746 Analyze (Type_Decl);
5748 -- After the implicit base is analyzed its Etype needs to be changed
5749 -- to reflect the fact that it is derived from the parent type which
5750 -- was ignored during analysis. We also set the size at this point.
5752 Set_Etype (Implicit_Base, Parent_Type);
5754 Set_Size_Info (Implicit_Base, Parent_Type);
5755 Set_RM_Size (Implicit_Base, RM_Size (Parent_Type));
5756 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type));
5758 -- Copy other flags from parent type
5760 Set_Has_Non_Standard_Rep
5761 (Implicit_Base, Has_Non_Standard_Rep
5763 Set_Has_Pragma_Ordered
5764 (Implicit_Base, Has_Pragma_Ordered
5766 Set_Has_Delayed_Freeze (Implicit_Base);
5768 -- Process the subtype indication including a validation check on the
5769 -- constraint, if any. If a constraint is given, its bounds must be
5770 -- implicitly converted to the new type.
5772 if Nkind (Indic) = N_Subtype_Indication then
5774 R : constant Node_Id :=
5775 Range_Expression (Constraint (Indic));
5778 if Nkind (R) = N_Range then
5779 Hi := Build_Scalar_Bound
5780 (High_Bound (R), Parent_Type, Implicit_Base);
5781 Lo := Build_Scalar_Bound
5782 (Low_Bound (R), Parent_Type, Implicit_Base);
5785 -- Constraint is a Range attribute. Replace with explicit
5786 -- mention of the bounds of the prefix, which must be a
5789 Analyze (Prefix (R));
5791 Convert_To (Implicit_Base,
5792 Make_Attribute_Reference (Loc,
5793 Attribute_Name => Name_Last,
5795 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
5798 Convert_To (Implicit_Base,
5799 Make_Attribute_Reference (Loc,
5800 Attribute_Name => Name_First,
5802 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
5809 (Type_High_Bound (Parent_Type),
5810 Parent_Type, Implicit_Base);
5813 (Type_Low_Bound (Parent_Type),
5814 Parent_Type, Implicit_Base);
5822 -- If we constructed a default range for the case where no range
5823 -- was given, then the expressions in the range must not freeze
5824 -- since they do not correspond to expressions in the source.
5826 if Nkind (Indic) /= N_Subtype_Indication then
5827 Set_Must_Not_Freeze (Lo);
5828 Set_Must_Not_Freeze (Hi);
5829 Set_Must_Not_Freeze (Rang_Expr);
5833 Make_Subtype_Declaration (Loc,
5834 Defining_Identifier => Derived_Type,
5835 Subtype_Indication =>
5836 Make_Subtype_Indication (Loc,
5837 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
5839 Make_Range_Constraint (Loc,
5840 Range_Expression => Rang_Expr))));
5844 -- If pragma Discard_Names applies on the first subtype of the parent
5845 -- type, then it must be applied on this subtype as well.
5847 if Einfo.Discard_Names (First_Subtype (Parent_Type)) then
5848 Set_Discard_Names (Derived_Type);
5851 -- Apply a range check. Since this range expression doesn't have an
5852 -- Etype, we have to specifically pass the Source_Typ parameter. Is
5855 if Nkind (Indic) = N_Subtype_Indication then
5856 Apply_Range_Check (Range_Expression (Constraint (Indic)),
5858 Source_Typ => Entity (Subtype_Mark (Indic)));
5861 end Build_Derived_Enumeration_Type;
5863 --------------------------------
5864 -- Build_Derived_Numeric_Type --
5865 --------------------------------
5867 procedure Build_Derived_Numeric_Type
5869 Parent_Type : Entity_Id;
5870 Derived_Type : Entity_Id)
5872 Loc : constant Source_Ptr := Sloc (N);
5873 Tdef : constant Node_Id := Type_Definition (N);
5874 Indic : constant Node_Id := Subtype_Indication (Tdef);
5875 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
5876 No_Constraint : constant Boolean := Nkind (Indic) /=
5877 N_Subtype_Indication;
5878 Implicit_Base : Entity_Id;
5884 -- Process the subtype indication including a validation check on
5885 -- the constraint if any.
5887 Discard_Node (Process_Subtype (Indic, N));
5889 -- Introduce an implicit base type for the derived type even if there
5890 -- is no constraint attached to it, since this seems closer to the Ada
5894 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
5896 Set_Etype (Implicit_Base, Parent_Base);
5897 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
5898 Set_Size_Info (Implicit_Base, Parent_Base);
5899 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base));
5900 Set_Parent (Implicit_Base, Parent (Derived_Type));
5901 Set_Is_Known_Valid (Implicit_Base, Is_Known_Valid (Parent_Base));
5903 -- Set RM Size for discrete type or decimal fixed-point type
5904 -- Ordinary fixed-point is excluded, why???
5906 if Is_Discrete_Type (Parent_Base)
5907 or else Is_Decimal_Fixed_Point_Type (Parent_Base)
5909 Set_RM_Size (Implicit_Base, RM_Size (Parent_Base));
5912 Set_Has_Delayed_Freeze (Implicit_Base);
5914 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
5915 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
5917 Set_Scalar_Range (Implicit_Base,
5922 if Has_Infinities (Parent_Base) then
5923 Set_Includes_Infinities (Scalar_Range (Implicit_Base));
5926 -- The Derived_Type, which is the entity of the declaration, is a
5927 -- subtype of the implicit base. Its Ekind is a subtype, even in the
5928 -- absence of an explicit constraint.
5930 Set_Etype (Derived_Type, Implicit_Base);
5932 -- If we did not have a constraint, then the Ekind is set from the
5933 -- parent type (otherwise Process_Subtype has set the bounds)
5935 if No_Constraint then
5936 Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type)));
5939 -- If we did not have a range constraint, then set the range from the
5940 -- parent type. Otherwise, the Process_Subtype call has set the bounds.
5943 or else not Has_Range_Constraint (Indic)
5945 Set_Scalar_Range (Derived_Type,
5947 Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)),
5948 High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type))));
5949 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
5951 if Has_Infinities (Parent_Type) then
5952 Set_Includes_Infinities (Scalar_Range (Derived_Type));
5955 Set_Is_Known_Valid (Derived_Type, Is_Known_Valid (Parent_Type));
5958 Set_Is_Descendent_Of_Address (Derived_Type,
5959 Is_Descendent_Of_Address (Parent_Type));
5960 Set_Is_Descendent_Of_Address (Implicit_Base,
5961 Is_Descendent_Of_Address (Parent_Type));
5963 -- Set remaining type-specific fields, depending on numeric type
5965 if Is_Modular_Integer_Type (Parent_Type) then
5966 Set_Modulus (Implicit_Base, Modulus (Parent_Base));
5968 Set_Non_Binary_Modulus
5969 (Implicit_Base, Non_Binary_Modulus (Parent_Base));
5972 (Implicit_Base, Is_Known_Valid (Parent_Base));
5974 elsif Is_Floating_Point_Type (Parent_Type) then
5976 -- Digits of base type is always copied from the digits value of
5977 -- the parent base type, but the digits of the derived type will
5978 -- already have been set if there was a constraint present.
5980 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
5981 Set_Float_Rep (Implicit_Base, Float_Rep (Parent_Base));
5983 if No_Constraint then
5984 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type));
5987 elsif Is_Fixed_Point_Type (Parent_Type) then
5989 -- Small of base type and derived type are always copied from the
5990 -- parent base type, since smalls never change. The delta of the
5991 -- base type is also copied from the parent base type. However the
5992 -- delta of the derived type will have been set already if a
5993 -- constraint was present.
5995 Set_Small_Value (Derived_Type, Small_Value (Parent_Base));
5996 Set_Small_Value (Implicit_Base, Small_Value (Parent_Base));
5997 Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base));
5999 if No_Constraint then
6000 Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type));
6003 -- The scale and machine radix in the decimal case are always
6004 -- copied from the parent base type.
6006 if Is_Decimal_Fixed_Point_Type (Parent_Type) then
6007 Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base));
6008 Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base));
6010 Set_Machine_Radix_10
6011 (Derived_Type, Machine_Radix_10 (Parent_Base));
6012 Set_Machine_Radix_10
6013 (Implicit_Base, Machine_Radix_10 (Parent_Base));
6015 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6017 if No_Constraint then
6018 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base));
6021 -- the analysis of the subtype_indication sets the
6022 -- digits value of the derived type.
6029 -- The type of the bounds is that of the parent type, and they
6030 -- must be converted to the derived type.
6032 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
6034 -- The implicit_base should be frozen when the derived type is frozen,
6035 -- but note that it is used in the conversions of the bounds. For fixed
6036 -- types we delay the determination of the bounds until the proper
6037 -- freezing point. For other numeric types this is rejected by GCC, for
6038 -- reasons that are currently unclear (???), so we choose to freeze the
6039 -- implicit base now. In the case of integers and floating point types
6040 -- this is harmless because subsequent representation clauses cannot
6041 -- affect anything, but it is still baffling that we cannot use the
6042 -- same mechanism for all derived numeric types.
6044 -- There is a further complication: actually *some* representation
6045 -- clauses can affect the implicit base type. Namely, attribute
6046 -- definition clauses for stream-oriented attributes need to set the
6047 -- corresponding TSS entries on the base type, and this normally cannot
6048 -- be done after the base type is frozen, so the circuitry in
6049 -- Sem_Ch13.New_Stream_Subprogram must account for this possibility and
6050 -- not use Set_TSS in this case.
6052 if Is_Fixed_Point_Type (Parent_Type) then
6053 Conditional_Delay (Implicit_Base, Parent_Type);
6055 Freeze_Before (N, Implicit_Base);
6057 end Build_Derived_Numeric_Type;
6059 --------------------------------
6060 -- Build_Derived_Private_Type --
6061 --------------------------------
6063 procedure Build_Derived_Private_Type
6065 Parent_Type : Entity_Id;
6066 Derived_Type : Entity_Id;
6067 Is_Completion : Boolean;
6068 Derive_Subps : Boolean := True)
6070 Loc : constant Source_Ptr := Sloc (N);
6071 Der_Base : Entity_Id;
6073 Full_Decl : Node_Id := Empty;
6074 Full_Der : Entity_Id;
6076 Last_Discr : Entity_Id;
6077 Par_Scope : constant Entity_Id := Scope (Base_Type (Parent_Type));
6078 Swapped : Boolean := False;
6080 procedure Copy_And_Build;
6081 -- Copy derived type declaration, replace parent with its full view,
6082 -- and analyze new declaration.
6084 --------------------
6085 -- Copy_And_Build --
6086 --------------------
6088 procedure Copy_And_Build is
6092 if Ekind (Parent_Type) in Record_Kind
6094 (Ekind (Parent_Type) in Enumeration_Kind
6095 and then not Is_Standard_Character_Type (Parent_Type)
6096 and then not Is_Generic_Type (Root_Type (Parent_Type)))
6098 Full_N := New_Copy_Tree (N);
6099 Insert_After (N, Full_N);
6100 Build_Derived_Type (
6101 Full_N, Parent_Type, Full_Der, True, Derive_Subps => False);
6104 Build_Derived_Type (
6105 N, Parent_Type, Full_Der, True, Derive_Subps => False);
6109 -- Start of processing for Build_Derived_Private_Type
6112 if Is_Tagged_Type (Parent_Type) then
6113 Full_P := Full_View (Parent_Type);
6115 -- A type extension of a type with unknown discriminants is an
6116 -- indefinite type that the back-end cannot handle directly.
6117 -- We treat it as a private type, and build a completion that is
6118 -- derived from the full view of the parent, and hopefully has
6119 -- known discriminants.
6121 -- If the full view of the parent type has an underlying record view,
6122 -- use it to generate the underlying record view of this derived type
6123 -- (required for chains of derivations with unknown discriminants).
6125 -- Minor optimization: we avoid the generation of useless underlying
6126 -- record view entities if the private type declaration has unknown
6127 -- discriminants but its corresponding full view has no
6130 if Has_Unknown_Discriminants (Parent_Type)
6131 and then Present (Full_P)
6132 and then (Has_Discriminants (Full_P)
6133 or else Present (Underlying_Record_View (Full_P)))
6134 and then not In_Open_Scopes (Par_Scope)
6135 and then Expander_Active
6138 Full_Der : constant Entity_Id := Make_Temporary (Loc, 'T');
6139 New_Ext : constant Node_Id :=
6141 (Record_Extension_Part (Type_Definition (N)));
6145 Build_Derived_Record_Type
6146 (N, Parent_Type, Derived_Type, Derive_Subps);
6148 -- Build anonymous completion, as a derivation from the full
6149 -- view of the parent. This is not a completion in the usual
6150 -- sense, because the current type is not private.
6153 Make_Full_Type_Declaration (Loc,
6154 Defining_Identifier => Full_Der,
6156 Make_Derived_Type_Definition (Loc,
6157 Subtype_Indication =>
6159 (Subtype_Indication (Type_Definition (N))),
6160 Record_Extension_Part => New_Ext));
6162 -- If the parent type has an underlying record view, use it
6163 -- here to build the new underlying record view.
6165 if Present (Underlying_Record_View (Full_P)) then
6167 (Nkind (Subtype_Indication (Type_Definition (Decl)))
6169 Set_Entity (Subtype_Indication (Type_Definition (Decl)),
6170 Underlying_Record_View (Full_P));
6173 Install_Private_Declarations (Par_Scope);
6174 Install_Visible_Declarations (Par_Scope);
6175 Insert_Before (N, Decl);
6177 -- Mark entity as an underlying record view before analysis,
6178 -- to avoid generating the list of its primitive operations
6179 -- (which is not really required for this entity) and thus
6180 -- prevent spurious errors associated with missing overriding
6181 -- of abstract primitives (overridden only for Derived_Type).
6183 Set_Ekind (Full_Der, E_Record_Type);
6184 Set_Is_Underlying_Record_View (Full_Der);
6188 pragma Assert (Has_Discriminants (Full_Der)
6189 and then not Has_Unknown_Discriminants (Full_Der));
6191 Uninstall_Declarations (Par_Scope);
6193 -- Freeze the underlying record view, to prevent generation of
6194 -- useless dispatching information, which is simply shared with
6195 -- the real derived type.
6197 Set_Is_Frozen (Full_Der);
6199 -- Set up links between real entity and underlying record view
6201 Set_Underlying_Record_View (Derived_Type, Base_Type (Full_Der));
6202 Set_Underlying_Record_View (Base_Type (Full_Der), Derived_Type);
6205 -- If discriminants are known, build derived record
6208 Build_Derived_Record_Type
6209 (N, Parent_Type, Derived_Type, Derive_Subps);
6214 elsif Has_Discriminants (Parent_Type) then
6215 if Present (Full_View (Parent_Type)) then
6216 if not Is_Completion then
6218 -- Copy declaration for subsequent analysis, to provide a
6219 -- completion for what is a private declaration. Indicate that
6220 -- the full type is internally generated.
6222 Full_Decl := New_Copy_Tree (N);
6223 Full_Der := New_Copy (Derived_Type);
6224 Set_Comes_From_Source (Full_Decl, False);
6225 Set_Comes_From_Source (Full_Der, False);
6226 Set_Parent (Full_Der, Full_Decl);
6228 Insert_After (N, Full_Decl);
6231 -- If this is a completion, the full view being built is itself
6232 -- private. We build a subtype of the parent with the same
6233 -- constraints as this full view, to convey to the back end the
6234 -- constrained components and the size of this subtype. If the
6235 -- parent is constrained, its full view can serve as the
6236 -- underlying full view of the derived type.
6238 if No (Discriminant_Specifications (N)) then
6239 if Nkind (Subtype_Indication (Type_Definition (N))) =
6240 N_Subtype_Indication
6242 Build_Underlying_Full_View (N, Derived_Type, Parent_Type);
6244 elsif Is_Constrained (Full_View (Parent_Type)) then
6245 Set_Underlying_Full_View
6246 (Derived_Type, Full_View (Parent_Type));
6250 -- If there are new discriminants, the parent subtype is
6251 -- constrained by them, but it is not clear how to build
6252 -- the Underlying_Full_View in this case???
6259 -- Build partial view of derived type from partial view of parent
6261 Build_Derived_Record_Type
6262 (N, Parent_Type, Derived_Type, Derive_Subps);
6264 if Present (Full_View (Parent_Type)) and then not Is_Completion then
6265 if not In_Open_Scopes (Par_Scope)
6266 or else not In_Same_Source_Unit (N, Parent_Type)
6268 -- Swap partial and full views temporarily
6270 Install_Private_Declarations (Par_Scope);
6271 Install_Visible_Declarations (Par_Scope);
6275 -- Build full view of derived type from full view of parent which
6276 -- is now installed. Subprograms have been derived on the partial
6277 -- view, the completion does not derive them anew.
6279 if not Is_Tagged_Type (Parent_Type) then
6281 -- If the parent is itself derived from another private type,
6282 -- installing the private declarations has not affected its
6283 -- privacy status, so use its own full view explicitly.
6285 if Is_Private_Type (Parent_Type) then
6286 Build_Derived_Record_Type
6287 (Full_Decl, Full_View (Parent_Type), Full_Der, False);
6289 Build_Derived_Record_Type
6290 (Full_Decl, Parent_Type, Full_Der, False);
6294 -- If full view of parent is tagged, the completion inherits
6295 -- the proper primitive operations.
6297 Set_Defining_Identifier (Full_Decl, Full_Der);
6298 Build_Derived_Record_Type
6299 (Full_Decl, Parent_Type, Full_Der, Derive_Subps);
6302 -- The full declaration has been introduced into the tree and
6303 -- processed in the step above. It should not be analyzed again
6304 -- (when encountered later in the current list of declarations)
6305 -- to prevent spurious name conflicts. The full entity remains
6308 Set_Analyzed (Full_Decl);
6311 Uninstall_Declarations (Par_Scope);
6313 if In_Open_Scopes (Par_Scope) then
6314 Install_Visible_Declarations (Par_Scope);
6318 Der_Base := Base_Type (Derived_Type);
6319 Set_Full_View (Derived_Type, Full_Der);
6320 Set_Full_View (Der_Base, Base_Type (Full_Der));
6322 -- Copy the discriminant list from full view to the partial views
6323 -- (base type and its subtype). Gigi requires that the partial and
6324 -- full views have the same discriminants.
6326 -- Note that since the partial view is pointing to discriminants
6327 -- in the full view, their scope will be that of the full view.
6328 -- This might cause some front end problems and need adjustment???
6330 Discr := First_Discriminant (Base_Type (Full_Der));
6331 Set_First_Entity (Der_Base, Discr);
6334 Last_Discr := Discr;
6335 Next_Discriminant (Discr);
6336 exit when No (Discr);
6339 Set_Last_Entity (Der_Base, Last_Discr);
6341 Set_First_Entity (Derived_Type, First_Entity (Der_Base));
6342 Set_Last_Entity (Derived_Type, Last_Entity (Der_Base));
6343 Set_Stored_Constraint (Full_Der, Stored_Constraint (Derived_Type));
6346 -- If this is a completion, the derived type stays private and
6347 -- there is no need to create a further full view, except in the
6348 -- unusual case when the derivation is nested within a child unit,
6354 elsif Present (Full_View (Parent_Type))
6355 and then Has_Discriminants (Full_View (Parent_Type))
6357 if Has_Unknown_Discriminants (Parent_Type)
6358 and then Nkind (Subtype_Indication (Type_Definition (N))) =
6359 N_Subtype_Indication
6362 ("cannot constrain type with unknown discriminants",
6363 Subtype_Indication (Type_Definition (N)));
6367 -- If full view of parent is a record type, build full view as a
6368 -- derivation from the parent's full view. Partial view remains
6369 -- private. For code generation and linking, the full view must have
6370 -- the same public status as the partial one. This full view is only
6371 -- needed if the parent type is in an enclosing scope, so that the
6372 -- full view may actually become visible, e.g. in a child unit. This
6373 -- is both more efficient, and avoids order of freezing problems with
6374 -- the added entities.
6376 if not Is_Private_Type (Full_View (Parent_Type))
6377 and then (In_Open_Scopes (Scope (Parent_Type)))
6380 Make_Defining_Identifier
6381 (Sloc (Derived_Type), Chars (Derived_Type));
6382 Set_Is_Itype (Full_Der);
6383 Set_Has_Private_Declaration (Full_Der);
6384 Set_Has_Private_Declaration (Derived_Type);
6385 Set_Associated_Node_For_Itype (Full_Der, N);
6386 Set_Parent (Full_Der, Parent (Derived_Type));
6387 Set_Full_View (Derived_Type, Full_Der);
6388 Set_Is_Public (Full_Der, Is_Public (Derived_Type));
6389 Full_P := Full_View (Parent_Type);
6390 Exchange_Declarations (Parent_Type);
6392 Exchange_Declarations (Full_P);
6395 Build_Derived_Record_Type
6396 (N, Full_View (Parent_Type), Derived_Type,
6397 Derive_Subps => False);
6400 -- In any case, the primitive operations are inherited from the
6401 -- parent type, not from the internal full view.
6403 Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type));
6405 if Derive_Subps then
6406 Derive_Subprograms (Parent_Type, Derived_Type);
6410 -- Untagged type, No discriminants on either view
6412 if Nkind (Subtype_Indication (Type_Definition (N))) =
6413 N_Subtype_Indication
6416 ("illegal constraint on type without discriminants", N);
6419 if Present (Discriminant_Specifications (N))
6420 and then Present (Full_View (Parent_Type))
6421 and then not Is_Tagged_Type (Full_View (Parent_Type))
6423 Error_Msg_N ("cannot add discriminants to untagged type", N);
6426 Set_Stored_Constraint (Derived_Type, No_Elist);
6427 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6428 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
6429 Set_Has_Controlled_Component
6430 (Derived_Type, Has_Controlled_Component
6433 -- Direct controlled types do not inherit Finalize_Storage_Only flag
6435 if not Is_Controlled (Parent_Type) then
6436 Set_Finalize_Storage_Only
6437 (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type));
6440 -- Construct the implicit full view by deriving from full view of the
6441 -- parent type. In order to get proper visibility, we install the
6442 -- parent scope and its declarations.
6444 -- ??? If the parent is untagged private and its completion is
6445 -- tagged, this mechanism will not work because we cannot derive from
6446 -- the tagged full view unless we have an extension.
6448 if Present (Full_View (Parent_Type))
6449 and then not Is_Tagged_Type (Full_View (Parent_Type))
6450 and then not Is_Completion
6453 Make_Defining_Identifier
6454 (Sloc (Derived_Type), Chars (Derived_Type));
6455 Set_Is_Itype (Full_Der);
6456 Set_Has_Private_Declaration (Full_Der);
6457 Set_Has_Private_Declaration (Derived_Type);
6458 Set_Associated_Node_For_Itype (Full_Der, N);
6459 Set_Parent (Full_Der, Parent (Derived_Type));
6460 Set_Full_View (Derived_Type, Full_Der);
6462 if not In_Open_Scopes (Par_Scope) then
6463 Install_Private_Declarations (Par_Scope);
6464 Install_Visible_Declarations (Par_Scope);
6466 Uninstall_Declarations (Par_Scope);
6468 -- If parent scope is open and in another unit, and parent has a
6469 -- completion, then the derivation is taking place in the visible
6470 -- part of a child unit. In that case retrieve the full view of
6471 -- the parent momentarily.
6473 elsif not In_Same_Source_Unit (N, Parent_Type) then
6474 Full_P := Full_View (Parent_Type);
6475 Exchange_Declarations (Parent_Type);
6477 Exchange_Declarations (Full_P);
6479 -- Otherwise it is a local derivation
6485 Set_Scope (Full_Der, Current_Scope);
6486 Set_Is_First_Subtype (Full_Der,
6487 Is_First_Subtype (Derived_Type));
6488 Set_Has_Size_Clause (Full_Der, False);
6489 Set_Has_Alignment_Clause (Full_Der, False);
6490 Set_Next_Entity (Full_Der, Empty);
6491 Set_Has_Delayed_Freeze (Full_Der);
6492 Set_Is_Frozen (Full_Der, False);
6493 Set_Freeze_Node (Full_Der, Empty);
6494 Set_Depends_On_Private (Full_Der,
6495 Has_Private_Component (Full_Der));
6496 Set_Public_Status (Full_Der);
6500 Set_Has_Unknown_Discriminants (Derived_Type,
6501 Has_Unknown_Discriminants (Parent_Type));
6503 if Is_Private_Type (Derived_Type) then
6504 Set_Private_Dependents (Derived_Type, New_Elmt_List);
6507 if Is_Private_Type (Parent_Type)
6508 and then Base_Type (Parent_Type) = Parent_Type
6509 and then In_Open_Scopes (Scope (Parent_Type))
6511 Append_Elmt (Derived_Type, Private_Dependents (Parent_Type));
6513 if Is_Child_Unit (Scope (Current_Scope))
6514 and then Is_Completion
6515 and then In_Private_Part (Current_Scope)
6516 and then Scope (Parent_Type) /= Current_Scope
6518 -- This is the unusual case where a type completed by a private
6519 -- derivation occurs within a package nested in a child unit, and
6520 -- the parent is declared in an ancestor. In this case, the full
6521 -- view of the parent type will become visible in the body of
6522 -- the enclosing child, and only then will the current type be
6523 -- possibly non-private. We build a underlying full view that
6524 -- will be installed when the enclosing child body is compiled.
6527 Make_Defining_Identifier
6528 (Sloc (Derived_Type), Chars (Derived_Type));
6529 Set_Is_Itype (Full_Der);
6530 Build_Itype_Reference (Full_Der, N);
6532 -- The full view will be used to swap entities on entry/exit to
6533 -- the body, and must appear in the entity list for the package.
6535 Append_Entity (Full_Der, Scope (Derived_Type));
6536 Set_Has_Private_Declaration (Full_Der);
6537 Set_Has_Private_Declaration (Derived_Type);
6538 Set_Associated_Node_For_Itype (Full_Der, N);
6539 Set_Parent (Full_Der, Parent (Derived_Type));
6540 Full_P := Full_View (Parent_Type);
6541 Exchange_Declarations (Parent_Type);
6543 Exchange_Declarations (Full_P);
6544 Set_Underlying_Full_View (Derived_Type, Full_Der);
6547 end Build_Derived_Private_Type;
6549 -------------------------------
6550 -- Build_Derived_Record_Type --
6551 -------------------------------
6555 -- Ideally we would like to use the same model of type derivation for
6556 -- tagged and untagged record types. Unfortunately this is not quite
6557 -- possible because the semantics of representation clauses is different
6558 -- for tagged and untagged records under inheritance. Consider the
6561 -- type R (...) is [tagged] record ... end record;
6562 -- type T (...) is new R (...) [with ...];
6564 -- The representation clauses for T can specify a completely different
6565 -- record layout from R's. Hence the same component can be placed in two
6566 -- very different positions in objects of type T and R. If R and T are
6567 -- tagged types, representation clauses for T can only specify the layout
6568 -- of non inherited components, thus components that are common in R and T
6569 -- have the same position in objects of type R and T.
6571 -- This has two implications. The first is that the entire tree for R's
6572 -- declaration needs to be copied for T in the untagged case, so that T
6573 -- can be viewed as a record type of its own with its own representation
6574 -- clauses. The second implication is the way we handle discriminants.
6575 -- Specifically, in the untagged case we need a way to communicate to Gigi
6576 -- what are the real discriminants in the record, while for the semantics
6577 -- we need to consider those introduced by the user to rename the
6578 -- discriminants in the parent type. This is handled by introducing the
6579 -- notion of stored discriminants. See below for more.
6581 -- Fortunately the way regular components are inherited can be handled in
6582 -- the same way in tagged and untagged types.
6584 -- To complicate things a bit more the private view of a private extension
6585 -- cannot be handled in the same way as the full view (for one thing the
6586 -- semantic rules are somewhat different). We will explain what differs
6589 -- 2. DISCRIMINANTS UNDER INHERITANCE
6591 -- The semantic rules governing the discriminants of derived types are
6594 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
6595 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
6597 -- If parent type has discriminants, then the discriminants that are
6598 -- declared in the derived type are [3.4 (11)]:
6600 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
6603 -- o Otherwise, each discriminant of the parent type (implicitly declared
6604 -- in the same order with the same specifications). In this case, the
6605 -- discriminants are said to be "inherited", or if unknown in the parent
6606 -- are also unknown in the derived type.
6608 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
6610 -- o The parent subtype shall be constrained;
6612 -- o If the parent type is not a tagged type, then each discriminant of
6613 -- the derived type shall be used in the constraint defining a parent
6614 -- subtype. [Implementation note: This ensures that the new discriminant
6615 -- can share storage with an existing discriminant.]
6617 -- For the derived type each discriminant of the parent type is either
6618 -- inherited, constrained to equal some new discriminant of the derived
6619 -- type, or constrained to the value of an expression.
6621 -- When inherited or constrained to equal some new discriminant, the
6622 -- parent discriminant and the discriminant of the derived type are said
6625 -- If a discriminant of the parent type is constrained to a specific value
6626 -- in the derived type definition, then the discriminant is said to be
6627 -- "specified" by that derived type definition.
6629 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES
6631 -- We have spoken about stored discriminants in point 1 (introduction)
6632 -- above. There are two sort of stored discriminants: implicit and
6633 -- explicit. As long as the derived type inherits the same discriminants as
6634 -- the root record type, stored discriminants are the same as regular
6635 -- discriminants, and are said to be implicit. However, if any discriminant
6636 -- in the root type was renamed in the derived type, then the derived
6637 -- type will contain explicit stored discriminants. Explicit stored
6638 -- discriminants are discriminants in addition to the semantically visible
6639 -- discriminants defined for the derived type. Stored discriminants are
6640 -- used by Gigi to figure out what are the physical discriminants in
6641 -- objects of the derived type (see precise definition in einfo.ads).
6642 -- As an example, consider the following:
6644 -- type R (D1, D2, D3 : Int) is record ... end record;
6645 -- type T1 is new R;
6646 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
6647 -- type T3 is new T2;
6648 -- type T4 (Y : Int) is new T3 (Y, 99);
6650 -- The following table summarizes the discriminants and stored
6651 -- discriminants in R and T1 through T4.
6653 -- Type Discrim Stored Discrim Comment
6654 -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R
6655 -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1
6656 -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2
6657 -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3
6658 -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4
6660 -- Field Corresponding_Discriminant (abbreviated CD below) allows us to
6661 -- find the corresponding discriminant in the parent type, while
6662 -- Original_Record_Component (abbreviated ORC below), the actual physical
6663 -- component that is renamed. Finally the field Is_Completely_Hidden
6664 -- (abbreviated ICH below) is set for all explicit stored discriminants
6665 -- (see einfo.ads for more info). For the above example this gives:
6667 -- Discrim CD ORC ICH
6668 -- ^^^^^^^ ^^ ^^^ ^^^
6669 -- D1 in R empty itself no
6670 -- D2 in R empty itself no
6671 -- D3 in R empty itself no
6673 -- D1 in T1 D1 in R itself no
6674 -- D2 in T1 D2 in R itself no
6675 -- D3 in T1 D3 in R itself no
6677 -- X1 in T2 D3 in T1 D3 in T2 no
6678 -- X2 in T2 D1 in T1 D1 in T2 no
6679 -- D1 in T2 empty itself yes
6680 -- D2 in T2 empty itself yes
6681 -- D3 in T2 empty itself yes
6683 -- X1 in T3 X1 in T2 D3 in T3 no
6684 -- X2 in T3 X2 in T2 D1 in T3 no
6685 -- D1 in T3 empty itself yes
6686 -- D2 in T3 empty itself yes
6687 -- D3 in T3 empty itself yes
6689 -- Y in T4 X1 in T3 D3 in T3 no
6690 -- D1 in T3 empty itself yes
6691 -- D2 in T3 empty itself yes
6692 -- D3 in T3 empty itself yes
6694 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES
6696 -- Type derivation for tagged types is fairly straightforward. If no
6697 -- discriminants are specified by the derived type, these are inherited
6698 -- from the parent. No explicit stored discriminants are ever necessary.
6699 -- The only manipulation that is done to the tree is that of adding a
6700 -- _parent field with parent type and constrained to the same constraint
6701 -- specified for the parent in the derived type definition. For instance:
6703 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
6704 -- type T1 is new R with null record;
6705 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
6707 -- are changed into:
6709 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
6710 -- _parent : R (D1, D2, D3);
6713 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
6714 -- _parent : T1 (X2, 88, X1);
6717 -- The discriminants actually present in R, T1 and T2 as well as their CD,
6718 -- ORC and ICH fields are:
6720 -- Discrim CD ORC ICH
6721 -- ^^^^^^^ ^^ ^^^ ^^^
6722 -- D1 in R empty itself no
6723 -- D2 in R empty itself no
6724 -- D3 in R empty itself no
6726 -- D1 in T1 D1 in R D1 in R no
6727 -- D2 in T1 D2 in R D2 in R no
6728 -- D3 in T1 D3 in R D3 in R no
6730 -- X1 in T2 D3 in T1 D3 in R no
6731 -- X2 in T2 D1 in T1 D1 in R no
6733 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS
6735 -- Regardless of whether we dealing with a tagged or untagged type
6736 -- we will transform all derived type declarations of the form
6738 -- type T is new R (...) [with ...];
6740 -- subtype S is R (...);
6741 -- type T is new S [with ...];
6743 -- type BT is new R [with ...];
6744 -- subtype T is BT (...);
6746 -- That is, the base derived type is constrained only if it has no
6747 -- discriminants. The reason for doing this is that GNAT's semantic model
6748 -- assumes that a base type with discriminants is unconstrained.
6750 -- Note that, strictly speaking, the above transformation is not always
6751 -- correct. Consider for instance the following excerpt from ACVC b34011a:
6753 -- procedure B34011A is
6754 -- type REC (D : integer := 0) is record
6759 -- type T6 is new Rec;
6760 -- function F return T6;
6765 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
6768 -- The definition of Q6.U is illegal. However transforming Q6.U into
6770 -- type BaseU is new T6;
6771 -- subtype U is BaseU (Q6.F.I)
6773 -- turns U into a legal subtype, which is incorrect. To avoid this problem
6774 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
6775 -- the transformation described above.
6777 -- There is another instance where the above transformation is incorrect.
6781 -- type Base (D : Integer) is tagged null record;
6782 -- procedure P (X : Base);
6784 -- type Der is new Base (2) with null record;
6785 -- procedure P (X : Der);
6788 -- Then the above transformation turns this into
6790 -- type Der_Base is new Base with null record;
6791 -- -- procedure P (X : Base) is implicitly inherited here
6792 -- -- as procedure P (X : Der_Base).
6794 -- subtype Der is Der_Base (2);
6795 -- procedure P (X : Der);
6796 -- -- The overriding of P (X : Der_Base) is illegal since we
6797 -- -- have a parameter conformance problem.
6799 -- To get around this problem, after having semantically processed Der_Base
6800 -- and the rewritten subtype declaration for Der, we copy Der_Base field
6801 -- Discriminant_Constraint from Der so that when parameter conformance is
6802 -- checked when P is overridden, no semantic errors are flagged.
6804 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS
6806 -- Regardless of whether we are dealing with a tagged or untagged type
6807 -- we will transform all derived type declarations of the form
6809 -- type R (D1, .., Dn : ...) is [tagged] record ...;
6810 -- type T is new R [with ...];
6812 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
6814 -- The reason for such transformation is that it allows us to implement a
6815 -- very clean form of component inheritance as explained below.
6817 -- Note that this transformation is not achieved by direct tree rewriting
6818 -- and manipulation, but rather by redoing the semantic actions that the
6819 -- above transformation will entail. This is done directly in routine
6820 -- Inherit_Components.
6822 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE
6824 -- In both tagged and untagged derived types, regular non discriminant
6825 -- components are inherited in the derived type from the parent type. In
6826 -- the absence of discriminants component, inheritance is straightforward
6827 -- as components can simply be copied from the parent.
6829 -- If the parent has discriminants, inheriting components constrained with
6830 -- these discriminants requires caution. Consider the following example:
6832 -- type R (D1, D2 : Positive) is [tagged] record
6833 -- S : String (D1 .. D2);
6836 -- type T1 is new R [with null record];
6837 -- type T2 (X : positive) is new R (1, X) [with null record];
6839 -- As explained in 6. above, T1 is rewritten as
6840 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
6841 -- which makes the treatment for T1 and T2 identical.
6843 -- What we want when inheriting S, is that references to D1 and D2 in R are
6844 -- replaced with references to their correct constraints, i.e. D1 and D2 in
6845 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
6846 -- with either discriminant references in the derived type or expressions.
6847 -- This replacement is achieved as follows: before inheriting R's
6848 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
6849 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
6850 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
6851 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
6852 -- by String (1 .. X).
6854 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS
6856 -- We explain here the rules governing private type extensions relevant to
6857 -- type derivation. These rules are explained on the following example:
6859 -- type D [(...)] is new A [(...)] with private; <-- partial view
6860 -- type D [(...)] is new P [(...)] with null record; <-- full view
6862 -- Type A is called the ancestor subtype of the private extension.
6863 -- Type P is the parent type of the full view of the private extension. It
6864 -- must be A or a type derived from A.
6866 -- The rules concerning the discriminants of private type extensions are
6869 -- o If a private extension inherits known discriminants from the ancestor
6870 -- subtype, then the full view shall also inherit its discriminants from
6871 -- the ancestor subtype and the parent subtype of the full view shall be
6872 -- constrained if and only if the ancestor subtype is constrained.
6874 -- o If a partial view has unknown discriminants, then the full view may
6875 -- define a definite or an indefinite subtype, with or without
6878 -- o If a partial view has neither known nor unknown discriminants, then
6879 -- the full view shall define a definite subtype.
6881 -- o If the ancestor subtype of a private extension has constrained
6882 -- discriminants, then the parent subtype of the full view shall impose a
6883 -- statically matching constraint on those discriminants.
6885 -- This means that only the following forms of private extensions are
6888 -- type D is new A with private; <-- partial view
6889 -- type D is new P with null record; <-- full view
6891 -- If A has no discriminants than P has no discriminants, otherwise P must
6892 -- inherit A's discriminants.
6894 -- type D is new A (...) with private; <-- partial view
6895 -- type D is new P (:::) with null record; <-- full view
6897 -- P must inherit A's discriminants and (...) and (:::) must statically
6900 -- subtype A is R (...);
6901 -- type D is new A with private; <-- partial view
6902 -- type D is new P with null record; <-- full view
6904 -- P must have inherited R's discriminants and must be derived from A or
6905 -- any of its subtypes.
6907 -- type D (..) is new A with private; <-- partial view
6908 -- type D (..) is new P [(:::)] with null record; <-- full view
6910 -- No specific constraints on P's discriminants or constraint (:::).
6911 -- Note that A can be unconstrained, but the parent subtype P must either
6912 -- be constrained or (:::) must be present.
6914 -- type D (..) is new A [(...)] with private; <-- partial view
6915 -- type D (..) is new P [(:::)] with null record; <-- full view
6917 -- P's constraints on A's discriminants must statically match those
6918 -- imposed by (...).
6920 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS
6922 -- The full view of a private extension is handled exactly as described
6923 -- above. The model chose for the private view of a private extension is
6924 -- the same for what concerns discriminants (i.e. they receive the same
6925 -- treatment as in the tagged case). However, the private view of the
6926 -- private extension always inherits the components of the parent base,
6927 -- without replacing any discriminant reference. Strictly speaking this is
6928 -- incorrect. However, Gigi never uses this view to generate code so this
6929 -- is a purely semantic issue. In theory, a set of transformations similar
6930 -- to those given in 5. and 6. above could be applied to private views of
6931 -- private extensions to have the same model of component inheritance as
6932 -- for non private extensions. However, this is not done because it would
6933 -- further complicate private type processing. Semantically speaking, this
6934 -- leaves us in an uncomfortable situation. As an example consider:
6937 -- type R (D : integer) is tagged record
6938 -- S : String (1 .. D);
6940 -- procedure P (X : R);
6941 -- type T is new R (1) with private;
6943 -- type T is new R (1) with null record;
6946 -- This is transformed into:
6949 -- type R (D : integer) is tagged record
6950 -- S : String (1 .. D);
6952 -- procedure P (X : R);
6953 -- type T is new R (1) with private;
6955 -- type BaseT is new R with null record;
6956 -- subtype T is BaseT (1);
6959 -- (strictly speaking the above is incorrect Ada)
6961 -- From the semantic standpoint the private view of private extension T
6962 -- should be flagged as constrained since one can clearly have
6966 -- in a unit withing Pack. However, when deriving subprograms for the
6967 -- private view of private extension T, T must be seen as unconstrained
6968 -- since T has discriminants (this is a constraint of the current
6969 -- subprogram derivation model). Thus, when processing the private view of
6970 -- a private extension such as T, we first mark T as unconstrained, we
6971 -- process it, we perform program derivation and just before returning from
6972 -- Build_Derived_Record_Type we mark T as constrained.
6974 -- ??? Are there are other uncomfortable cases that we will have to
6977 -- 10. RECORD_TYPE_WITH_PRIVATE complications
6979 -- Types that are derived from a visible record type and have a private
6980 -- extension present other peculiarities. They behave mostly like private
6981 -- types, but if they have primitive operations defined, these will not
6982 -- have the proper signatures for further inheritance, because other
6983 -- primitive operations will use the implicit base that we define for
6984 -- private derivations below. This affect subprogram inheritance (see
6985 -- Derive_Subprograms for details). We also derive the implicit base from
6986 -- the base type of the full view, so that the implicit base is a record
6987 -- type and not another private type, This avoids infinite loops.
6989 procedure Build_Derived_Record_Type
6991 Parent_Type : Entity_Id;
6992 Derived_Type : Entity_Id;
6993 Derive_Subps : Boolean := True)
6995 Discriminant_Specs : constant Boolean :=
6996 Present (Discriminant_Specifications (N));
6997 Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type);
6998 Loc : constant Source_Ptr := Sloc (N);
6999 Private_Extension : constant Boolean :=
7000 Nkind (N) = N_Private_Extension_Declaration;
7001 Assoc_List : Elist_Id;
7002 Constraint_Present : Boolean;
7004 Discrim : Entity_Id;
7006 Inherit_Discrims : Boolean := False;
7007 Last_Discrim : Entity_Id;
7008 New_Base : Entity_Id;
7010 New_Discrs : Elist_Id;
7011 New_Indic : Node_Id;
7012 Parent_Base : Entity_Id;
7013 Save_Etype : Entity_Id;
7014 Save_Discr_Constr : Elist_Id;
7015 Save_Next_Entity : Entity_Id;
7018 Discs : Elist_Id := New_Elmt_List;
7019 -- An empty Discs list means that there were no constraints in the
7020 -- subtype indication or that there was an error processing it.
7023 if Ekind (Parent_Type) = E_Record_Type_With_Private
7024 and then Present (Full_View (Parent_Type))
7025 and then Has_Discriminants (Parent_Type)
7027 Parent_Base := Base_Type (Full_View (Parent_Type));
7029 Parent_Base := Base_Type (Parent_Type);
7032 -- Before we start the previously documented transformations, here is
7033 -- little fix for size and alignment of tagged types. Normally when we
7034 -- derive type D from type P, we copy the size and alignment of P as the
7035 -- default for D, and in the absence of explicit representation clauses
7036 -- for D, the size and alignment are indeed the same as the parent.
7038 -- But this is wrong for tagged types, since fields may be added, and
7039 -- the default size may need to be larger, and the default alignment may
7040 -- need to be larger.
7042 -- We therefore reset the size and alignment fields in the tagged case.
7043 -- Note that the size and alignment will in any case be at least as
7044 -- large as the parent type (since the derived type has a copy of the
7045 -- parent type in the _parent field)
7047 -- The type is also marked as being tagged here, which is needed when
7048 -- processing components with a self-referential anonymous access type
7049 -- in the call to Check_Anonymous_Access_Components below. Note that
7050 -- this flag is also set later on for completeness.
7053 Set_Is_Tagged_Type (Derived_Type);
7054 Init_Size_Align (Derived_Type);
7057 -- STEP 0a: figure out what kind of derived type declaration we have
7059 if Private_Extension then
7061 Set_Ekind (Derived_Type, E_Record_Type_With_Private);
7064 Type_Def := Type_Definition (N);
7066 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
7067 -- Parent_Base can be a private type or private extension. However,
7068 -- for tagged types with an extension the newly added fields are
7069 -- visible and hence the Derived_Type is always an E_Record_Type.
7070 -- (except that the parent may have its own private fields).
7071 -- For untagged types we preserve the Ekind of the Parent_Base.
7073 if Present (Record_Extension_Part (Type_Def)) then
7074 Set_Ekind (Derived_Type, E_Record_Type);
7076 -- Create internal access types for components with anonymous
7079 if Ada_Version >= Ada_2005 then
7080 Check_Anonymous_Access_Components
7081 (N, Derived_Type, Derived_Type,
7082 Component_List (Record_Extension_Part (Type_Def)));
7086 Set_Ekind (Derived_Type, Ekind (Parent_Base));
7090 -- Indic can either be an N_Identifier if the subtype indication
7091 -- contains no constraint or an N_Subtype_Indication if the subtype
7092 -- indication has a constraint.
7094 Indic := Subtype_Indication (Type_Def);
7095 Constraint_Present := (Nkind (Indic) = N_Subtype_Indication);
7097 -- Check that the type has visible discriminants. The type may be
7098 -- a private type with unknown discriminants whose full view has
7099 -- discriminants which are invisible.
7101 if Constraint_Present then
7102 if not Has_Discriminants (Parent_Base)
7104 (Has_Unknown_Discriminants (Parent_Base)
7105 and then Is_Private_Type (Parent_Base))
7108 ("invalid constraint: type has no discriminant",
7109 Constraint (Indic));
7111 Constraint_Present := False;
7112 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7114 elsif Is_Constrained (Parent_Type) then
7116 ("invalid constraint: parent type is already constrained",
7117 Constraint (Indic));
7119 Constraint_Present := False;
7120 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7124 -- STEP 0b: If needed, apply transformation given in point 5. above
7126 if not Private_Extension
7127 and then Has_Discriminants (Parent_Type)
7128 and then not Discriminant_Specs
7129 and then (Is_Constrained (Parent_Type) or else Constraint_Present)
7131 -- First, we must analyze the constraint (see comment in point 5.)
7133 if Constraint_Present then
7134 New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic);
7136 if Has_Discriminants (Derived_Type)
7137 and then Has_Private_Declaration (Derived_Type)
7138 and then Present (Discriminant_Constraint (Derived_Type))
7140 -- Verify that constraints of the full view statically match
7141 -- those given in the partial view.
7147 C1 := First_Elmt (New_Discrs);
7148 C2 := First_Elmt (Discriminant_Constraint (Derived_Type));
7149 while Present (C1) and then Present (C2) loop
7150 if Fully_Conformant_Expressions (Node (C1), Node (C2))
7152 (Is_OK_Static_Expression (Node (C1))
7154 Is_OK_Static_Expression (Node (C2))
7156 Expr_Value (Node (C1)) = Expr_Value (Node (C2)))
7162 "constraint not conformant to previous declaration",
7173 -- Insert and analyze the declaration for the unconstrained base type
7175 New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B');
7178 Make_Full_Type_Declaration (Loc,
7179 Defining_Identifier => New_Base,
7181 Make_Derived_Type_Definition (Loc,
7182 Abstract_Present => Abstract_Present (Type_Def),
7183 Limited_Present => Limited_Present (Type_Def),
7184 Subtype_Indication =>
7185 New_Occurrence_Of (Parent_Base, Loc),
7186 Record_Extension_Part =>
7187 Relocate_Node (Record_Extension_Part (Type_Def)),
7188 Interface_List => Interface_List (Type_Def)));
7190 Set_Parent (New_Decl, Parent (N));
7191 Mark_Rewrite_Insertion (New_Decl);
7192 Insert_Before (N, New_Decl);
7194 -- In the extension case, make sure ancestor is frozen appropriately
7195 -- (see also non-discriminated case below).
7197 if Present (Record_Extension_Part (Type_Def))
7198 or else Is_Interface (Parent_Base)
7200 Freeze_Before (New_Decl, Parent_Type);
7203 -- Note that this call passes False for the Derive_Subps parameter
7204 -- because subprogram derivation is deferred until after creating
7205 -- the subtype (see below).
7208 (New_Decl, Parent_Base, New_Base,
7209 Is_Completion => True, Derive_Subps => False);
7211 -- ??? This needs re-examination to determine whether the
7212 -- above call can simply be replaced by a call to Analyze.
7214 Set_Analyzed (New_Decl);
7216 -- Insert and analyze the declaration for the constrained subtype
7218 if Constraint_Present then
7220 Make_Subtype_Indication (Loc,
7221 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
7222 Constraint => Relocate_Node (Constraint (Indic)));
7226 Constr_List : constant List_Id := New_List;
7231 C := First_Elmt (Discriminant_Constraint (Parent_Type));
7232 while Present (C) loop
7235 -- It is safe here to call New_Copy_Tree since
7236 -- Force_Evaluation was called on each constraint in
7237 -- Build_Discriminant_Constraints.
7239 Append (New_Copy_Tree (Expr), To => Constr_List);
7245 Make_Subtype_Indication (Loc,
7246 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
7248 Make_Index_Or_Discriminant_Constraint (Loc, Constr_List));
7253 Make_Subtype_Declaration (Loc,
7254 Defining_Identifier => Derived_Type,
7255 Subtype_Indication => New_Indic));
7259 -- Derivation of subprograms must be delayed until the full subtype
7260 -- has been established, to ensure proper overriding of subprograms
7261 -- inherited by full types. If the derivations occurred as part of
7262 -- the call to Build_Derived_Type above, then the check for type
7263 -- conformance would fail because earlier primitive subprograms
7264 -- could still refer to the full type prior the change to the new
7265 -- subtype and hence would not match the new base type created here.
7266 -- Subprograms are not derived, however, when Derive_Subps is False
7267 -- (since otherwise there could be redundant derivations).
7269 if Derive_Subps then
7270 Derive_Subprograms (Parent_Type, Derived_Type);
7273 -- For tagged types the Discriminant_Constraint of the new base itype
7274 -- is inherited from the first subtype so that no subtype conformance
7275 -- problem arise when the first subtype overrides primitive
7276 -- operations inherited by the implicit base type.
7279 Set_Discriminant_Constraint
7280 (New_Base, Discriminant_Constraint (Derived_Type));
7286 -- If we get here Derived_Type will have no discriminants or it will be
7287 -- a discriminated unconstrained base type.
7289 -- STEP 1a: perform preliminary actions/checks for derived tagged types
7293 -- The parent type is frozen for non-private extensions (RM 13.14(7))
7294 -- The declaration of a specific descendant of an interface type
7295 -- freezes the interface type (RM 13.14).
7297 if not Private_Extension or else Is_Interface (Parent_Base) then
7298 Freeze_Before (N, Parent_Type);
7301 -- In Ada 2005 (AI-344), the restriction that a derived tagged type
7302 -- cannot be declared at a deeper level than its parent type is
7303 -- removed. The check on derivation within a generic body is also
7304 -- relaxed, but there's a restriction that a derived tagged type
7305 -- cannot be declared in a generic body if it's derived directly
7306 -- or indirectly from a formal type of that generic.
7308 if Ada_Version >= Ada_2005 then
7309 if Present (Enclosing_Generic_Body (Derived_Type)) then
7311 Ancestor_Type : Entity_Id;
7314 -- Check to see if any ancestor of the derived type is a
7317 Ancestor_Type := Parent_Type;
7318 while not Is_Generic_Type (Ancestor_Type)
7319 and then Etype (Ancestor_Type) /= Ancestor_Type
7321 Ancestor_Type := Etype (Ancestor_Type);
7324 -- If the derived type does have a formal type as an
7325 -- ancestor, then it's an error if the derived type is
7326 -- declared within the body of the generic unit that
7327 -- declares the formal type in its generic formal part. It's
7328 -- sufficient to check whether the ancestor type is declared
7329 -- inside the same generic body as the derived type (such as
7330 -- within a nested generic spec), in which case the
7331 -- derivation is legal. If the formal type is declared
7332 -- outside of that generic body, then it's guaranteed that
7333 -- the derived type is declared within the generic body of
7334 -- the generic unit declaring the formal type.
7336 if Is_Generic_Type (Ancestor_Type)
7337 and then Enclosing_Generic_Body (Ancestor_Type) /=
7338 Enclosing_Generic_Body (Derived_Type)
7341 ("parent type of& must not be descendant of formal type"
7342 & " of an enclosing generic body",
7343 Indic, Derived_Type);
7348 elsif Type_Access_Level (Derived_Type) /=
7349 Type_Access_Level (Parent_Type)
7350 and then not Is_Generic_Type (Derived_Type)
7352 if Is_Controlled (Parent_Type) then
7354 ("controlled type must be declared at the library level",
7358 ("type extension at deeper accessibility level than parent",
7364 GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type);
7368 and then GB /= Enclosing_Generic_Body (Parent_Base)
7371 ("parent type of& must not be outside generic body"
7373 Indic, Derived_Type);
7379 -- Ada 2005 (AI-251)
7381 if Ada_Version >= Ada_2005 and then Is_Tagged then
7383 -- "The declaration of a specific descendant of an interface type
7384 -- freezes the interface type" (RM 13.14).
7389 if Is_Non_Empty_List (Interface_List (Type_Def)) then
7390 Iface := First (Interface_List (Type_Def));
7391 while Present (Iface) loop
7392 Freeze_Before (N, Etype (Iface));
7399 -- STEP 1b : preliminary cleanup of the full view of private types
7401 -- If the type is already marked as having discriminants, then it's the
7402 -- completion of a private type or private extension and we need to
7403 -- retain the discriminants from the partial view if the current
7404 -- declaration has Discriminant_Specifications so that we can verify
7405 -- conformance. However, we must remove any existing components that
7406 -- were inherited from the parent (and attached in Copy_And_Swap)
7407 -- because the full type inherits all appropriate components anyway, and
7408 -- we do not want the partial view's components interfering.
7410 if Has_Discriminants (Derived_Type) and then Discriminant_Specs then
7411 Discrim := First_Discriminant (Derived_Type);
7413 Last_Discrim := Discrim;
7414 Next_Discriminant (Discrim);
7415 exit when No (Discrim);
7418 Set_Last_Entity (Derived_Type, Last_Discrim);
7420 -- In all other cases wipe out the list of inherited components (even
7421 -- inherited discriminants), it will be properly rebuilt here.
7424 Set_First_Entity (Derived_Type, Empty);
7425 Set_Last_Entity (Derived_Type, Empty);
7428 -- STEP 1c: Initialize some flags for the Derived_Type
7430 -- The following flags must be initialized here so that
7431 -- Process_Discriminants can check that discriminants of tagged types do
7432 -- not have a default initial value and that access discriminants are
7433 -- only specified for limited records. For completeness, these flags are
7434 -- also initialized along with all the other flags below.
7436 -- AI-419: Limitedness is not inherited from an interface parent, so to
7437 -- be limited in that case the type must be explicitly declared as
7438 -- limited. However, task and protected interfaces are always limited.
7440 if Limited_Present (Type_Def) then
7441 Set_Is_Limited_Record (Derived_Type);
7443 elsif Is_Limited_Record (Parent_Type)
7444 or else (Present (Full_View (Parent_Type))
7445 and then Is_Limited_Record (Full_View (Parent_Type)))
7447 if not Is_Interface (Parent_Type)
7448 or else Is_Synchronized_Interface (Parent_Type)
7449 or else Is_Protected_Interface (Parent_Type)
7450 or else Is_Task_Interface (Parent_Type)
7452 Set_Is_Limited_Record (Derived_Type);
7456 -- STEP 2a: process discriminants of derived type if any
7458 Push_Scope (Derived_Type);
7460 if Discriminant_Specs then
7461 Set_Has_Unknown_Discriminants (Derived_Type, False);
7463 -- The following call initializes fields Has_Discriminants and
7464 -- Discriminant_Constraint, unless we are processing the completion
7465 -- of a private type declaration.
7467 Check_Or_Process_Discriminants (N, Derived_Type);
7469 -- For untagged types, the constraint on the Parent_Type must be
7470 -- present and is used to rename the discriminants.
7472 if not Is_Tagged and then not Has_Discriminants (Parent_Type) then
7473 Error_Msg_N ("untagged parent must have discriminants", Indic);
7475 elsif not Is_Tagged and then not Constraint_Present then
7477 ("discriminant constraint needed for derived untagged records",
7480 -- Otherwise the parent subtype must be constrained unless we have a
7481 -- private extension.
7483 elsif not Constraint_Present
7484 and then not Private_Extension
7485 and then not Is_Constrained (Parent_Type)
7488 ("unconstrained type not allowed in this context", Indic);
7490 elsif Constraint_Present then
7491 -- The following call sets the field Corresponding_Discriminant
7492 -- for the discriminants in the Derived_Type.
7494 Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True);
7496 -- For untagged types all new discriminants must rename
7497 -- discriminants in the parent. For private extensions new
7498 -- discriminants cannot rename old ones (implied by [7.3(13)]).
7500 Discrim := First_Discriminant (Derived_Type);
7501 while Present (Discrim) loop
7503 and then No (Corresponding_Discriminant (Discrim))
7506 ("new discriminants must constrain old ones", Discrim);
7508 elsif Private_Extension
7509 and then Present (Corresponding_Discriminant (Discrim))
7512 ("only static constraints allowed for parent"
7513 & " discriminants in the partial view", Indic);
7517 -- If a new discriminant is used in the constraint, then its
7518 -- subtype must be statically compatible with the parent
7519 -- discriminant's subtype (3.7(15)).
7521 if Present (Corresponding_Discriminant (Discrim))
7523 not Subtypes_Statically_Compatible
7525 Etype (Corresponding_Discriminant (Discrim)))
7528 ("subtype must be compatible with parent discriminant",
7532 Next_Discriminant (Discrim);
7535 -- Check whether the constraints of the full view statically
7536 -- match those imposed by the parent subtype [7.3(13)].
7538 if Present (Stored_Constraint (Derived_Type)) then
7543 C1 := First_Elmt (Discs);
7544 C2 := First_Elmt (Stored_Constraint (Derived_Type));
7545 while Present (C1) and then Present (C2) loop
7547 Fully_Conformant_Expressions (Node (C1), Node (C2))
7550 ("not conformant with previous declaration",
7561 -- STEP 2b: No new discriminants, inherit discriminants if any
7564 if Private_Extension then
7565 Set_Has_Unknown_Discriminants
7567 Has_Unknown_Discriminants (Parent_Type)
7568 or else Unknown_Discriminants_Present (N));
7570 -- The partial view of the parent may have unknown discriminants,
7571 -- but if the full view has discriminants and the parent type is
7572 -- in scope they must be inherited.
7574 elsif Has_Unknown_Discriminants (Parent_Type)
7576 (not Has_Discriminants (Parent_Type)
7577 or else not In_Open_Scopes (Scope (Parent_Type)))
7579 Set_Has_Unknown_Discriminants (Derived_Type);
7582 if not Has_Unknown_Discriminants (Derived_Type)
7583 and then not Has_Unknown_Discriminants (Parent_Base)
7584 and then Has_Discriminants (Parent_Type)
7586 Inherit_Discrims := True;
7587 Set_Has_Discriminants
7588 (Derived_Type, True);
7589 Set_Discriminant_Constraint
7590 (Derived_Type, Discriminant_Constraint (Parent_Base));
7593 -- The following test is true for private types (remember
7594 -- transformation 5. is not applied to those) and in an error
7597 if Constraint_Present then
7598 Discs := Build_Discriminant_Constraints (Parent_Type, Indic);
7601 -- For now mark a new derived type as constrained only if it has no
7602 -- discriminants. At the end of Build_Derived_Record_Type we properly
7603 -- set this flag in the case of private extensions. See comments in
7604 -- point 9. just before body of Build_Derived_Record_Type.
7608 not (Inherit_Discrims
7609 or else Has_Unknown_Discriminants (Derived_Type)));
7612 -- STEP 3: initialize fields of derived type
7614 Set_Is_Tagged_Type (Derived_Type, Is_Tagged);
7615 Set_Stored_Constraint (Derived_Type, No_Elist);
7617 -- Ada 2005 (AI-251): Private type-declarations can implement interfaces
7618 -- but cannot be interfaces
7620 if not Private_Extension
7621 and then Ekind (Derived_Type) /= E_Private_Type
7622 and then Ekind (Derived_Type) /= E_Limited_Private_Type
7624 if Interface_Present (Type_Def) then
7625 Analyze_Interface_Declaration (Derived_Type, Type_Def);
7628 Set_Interfaces (Derived_Type, No_Elist);
7631 -- Fields inherited from the Parent_Type
7634 (Derived_Type, Einfo.Discard_Names (Parent_Type));
7635 Set_Has_Specified_Layout
7636 (Derived_Type, Has_Specified_Layout (Parent_Type));
7637 Set_Is_Limited_Composite
7638 (Derived_Type, Is_Limited_Composite (Parent_Type));
7639 Set_Is_Private_Composite
7640 (Derived_Type, Is_Private_Composite (Parent_Type));
7642 -- Fields inherited from the Parent_Base
7644 Set_Has_Controlled_Component
7645 (Derived_Type, Has_Controlled_Component (Parent_Base));
7646 Set_Has_Non_Standard_Rep
7647 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
7648 Set_Has_Primitive_Operations
7649 (Derived_Type, Has_Primitive_Operations (Parent_Base));
7651 -- Fields inherited from the Parent_Base in the non-private case
7653 if Ekind (Derived_Type) = E_Record_Type then
7654 Set_Has_Complex_Representation
7655 (Derived_Type, Has_Complex_Representation (Parent_Base));
7658 -- Fields inherited from the Parent_Base for record types
7660 if Is_Record_Type (Derived_Type) then
7662 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
7663 -- Parent_Base can be a private type or private extension.
7665 if Present (Full_View (Parent_Base)) then
7666 Set_OK_To_Reorder_Components
7668 OK_To_Reorder_Components (Full_View (Parent_Base)));
7669 Set_Reverse_Bit_Order
7670 (Derived_Type, Reverse_Bit_Order (Full_View (Parent_Base)));
7672 Set_OK_To_Reorder_Components
7673 (Derived_Type, OK_To_Reorder_Components (Parent_Base));
7674 Set_Reverse_Bit_Order
7675 (Derived_Type, Reverse_Bit_Order (Parent_Base));
7679 -- Direct controlled types do not inherit Finalize_Storage_Only flag
7681 if not Is_Controlled (Parent_Type) then
7682 Set_Finalize_Storage_Only
7683 (Derived_Type, Finalize_Storage_Only (Parent_Type));
7686 -- Set fields for private derived types
7688 if Is_Private_Type (Derived_Type) then
7689 Set_Depends_On_Private (Derived_Type, True);
7690 Set_Private_Dependents (Derived_Type, New_Elmt_List);
7692 -- Inherit fields from non private record types. If this is the
7693 -- completion of a derivation from a private type, the parent itself
7694 -- is private, and the attributes come from its full view, which must
7698 if Is_Private_Type (Parent_Base)
7699 and then not Is_Record_Type (Parent_Base)
7701 Set_Component_Alignment
7702 (Derived_Type, Component_Alignment (Full_View (Parent_Base)));
7704 (Derived_Type, C_Pass_By_Copy (Full_View (Parent_Base)));
7706 Set_Component_Alignment
7707 (Derived_Type, Component_Alignment (Parent_Base));
7709 (Derived_Type, C_Pass_By_Copy (Parent_Base));
7713 -- Set fields for tagged types
7716 Set_Direct_Primitive_Operations (Derived_Type, New_Elmt_List);
7718 -- All tagged types defined in Ada.Finalization are controlled
7720 if Chars (Scope (Derived_Type)) = Name_Finalization
7721 and then Chars (Scope (Scope (Derived_Type))) = Name_Ada
7722 and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard
7724 Set_Is_Controlled (Derived_Type);
7726 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Base));
7729 -- Minor optimization: there is no need to generate the class-wide
7730 -- entity associated with an underlying record view.
7732 if not Is_Underlying_Record_View (Derived_Type) then
7733 Make_Class_Wide_Type (Derived_Type);
7736 Set_Is_Abstract_Type (Derived_Type, Abstract_Present (Type_Def));
7738 if Has_Discriminants (Derived_Type)
7739 and then Constraint_Present
7741 Set_Stored_Constraint
7742 (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs));
7745 if Ada_Version >= Ada_2005 then
7747 Ifaces_List : Elist_Id;
7750 -- Checks rules 3.9.4 (13/2 and 14/2)
7752 if Comes_From_Source (Derived_Type)
7753 and then not Is_Private_Type (Derived_Type)
7754 and then Is_Interface (Parent_Type)
7755 and then not Is_Interface (Derived_Type)
7757 if Is_Task_Interface (Parent_Type) then
7759 ("(Ada 2005) task type required (RM 3.9.4 (13.2))",
7762 elsif Is_Protected_Interface (Parent_Type) then
7764 ("(Ada 2005) protected type required (RM 3.9.4 (14.2))",
7769 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
7771 Check_Interfaces (N, Type_Def);
7773 -- Ada 2005 (AI-251): Collect the list of progenitors that are
7774 -- not already in the parents.
7778 Ifaces_List => Ifaces_List,
7779 Exclude_Parents => True);
7781 Set_Interfaces (Derived_Type, Ifaces_List);
7783 -- If the derived type is the anonymous type created for
7784 -- a declaration whose parent has a constraint, propagate
7785 -- the interface list to the source type. This must be done
7786 -- prior to the completion of the analysis of the source type
7787 -- because the components in the extension may contain current
7788 -- instances whose legality depends on some ancestor.
7790 if Is_Itype (Derived_Type) then
7792 Def : constant Node_Id :=
7793 Associated_Node_For_Itype (Derived_Type);
7796 and then Nkind (Def) = N_Full_Type_Declaration
7799 (Defining_Identifier (Def), Ifaces_List);
7807 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Base));
7808 Set_Has_Non_Standard_Rep
7809 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
7812 -- STEP 4: Inherit components from the parent base and constrain them.
7813 -- Apply the second transformation described in point 6. above.
7815 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
7816 or else not Has_Discriminants (Parent_Type)
7817 or else not Is_Constrained (Parent_Type)
7821 Constrs := Discriminant_Constraint (Parent_Type);
7826 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
7828 -- STEP 5a: Copy the parent record declaration for untagged types
7830 if not Is_Tagged then
7832 -- Discriminant_Constraint (Derived_Type) has been properly
7833 -- constructed. Save it and temporarily set it to Empty because we
7834 -- do not want the call to New_Copy_Tree below to mess this list.
7836 if Has_Discriminants (Derived_Type) then
7837 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
7838 Set_Discriminant_Constraint (Derived_Type, No_Elist);
7840 Save_Discr_Constr := No_Elist;
7843 -- Save the Etype field of Derived_Type. It is correctly set now,
7844 -- but the call to New_Copy tree may remap it to point to itself,
7845 -- which is not what we want. Ditto for the Next_Entity field.
7847 Save_Etype := Etype (Derived_Type);
7848 Save_Next_Entity := Next_Entity (Derived_Type);
7850 -- Assoc_List maps all stored discriminants in the Parent_Base to
7851 -- stored discriminants in the Derived_Type. It is fundamental that
7852 -- no types or itypes with discriminants other than the stored
7853 -- discriminants appear in the entities declared inside
7854 -- Derived_Type, since the back end cannot deal with it.
7858 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
7860 -- Restore the fields saved prior to the New_Copy_Tree call
7861 -- and compute the stored constraint.
7863 Set_Etype (Derived_Type, Save_Etype);
7864 Set_Next_Entity (Derived_Type, Save_Next_Entity);
7866 if Has_Discriminants (Derived_Type) then
7867 Set_Discriminant_Constraint
7868 (Derived_Type, Save_Discr_Constr);
7869 Set_Stored_Constraint
7870 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
7871 Replace_Components (Derived_Type, New_Decl);
7874 -- Insert the new derived type declaration
7876 Rewrite (N, New_Decl);
7878 -- STEP 5b: Complete the processing for record extensions in generics
7880 -- There is no completion for record extensions declared in the
7881 -- parameter part of a generic, so we need to complete processing for
7882 -- these generic record extensions here. The Record_Type_Definition call
7883 -- will change the Ekind of the components from E_Void to E_Component.
7885 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
7886 Record_Type_Definition (Empty, Derived_Type);
7888 -- STEP 5c: Process the record extension for non private tagged types
7890 elsif not Private_Extension then
7892 -- Add the _parent field in the derived type
7894 Expand_Record_Extension (Derived_Type, Type_Def);
7896 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
7897 -- implemented interfaces if we are in expansion mode
7900 and then Has_Interfaces (Derived_Type)
7902 Add_Interface_Tag_Components (N, Derived_Type);
7905 -- Analyze the record extension
7907 Record_Type_Definition
7908 (Record_Extension_Part (Type_Def), Derived_Type);
7913 -- Nothing else to do if there is an error in the derivation.
7914 -- An unusual case: the full view may be derived from a type in an
7915 -- instance, when the partial view was used illegally as an actual
7916 -- in that instance, leading to a circular definition.
7918 if Etype (Derived_Type) = Any_Type
7919 or else Etype (Parent_Type) = Derived_Type
7924 -- Set delayed freeze and then derive subprograms, we need to do
7925 -- this in this order so that derived subprograms inherit the
7926 -- derived freeze if necessary.
7928 Set_Has_Delayed_Freeze (Derived_Type);
7930 if Derive_Subps then
7931 Derive_Subprograms (Parent_Type, Derived_Type);
7934 -- If we have a private extension which defines a constrained derived
7935 -- type mark as constrained here after we have derived subprograms. See
7936 -- comment on point 9. just above the body of Build_Derived_Record_Type.
7938 if Private_Extension and then Inherit_Discrims then
7939 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
7940 Set_Is_Constrained (Derived_Type, True);
7941 Set_Discriminant_Constraint (Derived_Type, Discs);
7943 elsif Is_Constrained (Parent_Type) then
7945 (Derived_Type, True);
7946 Set_Discriminant_Constraint
7947 (Derived_Type, Discriminant_Constraint (Parent_Type));
7951 -- Update the class-wide type, which shares the now-completed entity
7952 -- list with its specific type. In case of underlying record views,
7953 -- we do not generate the corresponding class wide entity.
7956 and then not Is_Underlying_Record_View (Derived_Type)
7959 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
7961 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
7964 -- Update the scope of anonymous access types of discriminants and other
7965 -- components, to prevent scope anomalies in gigi, when the derivation
7966 -- appears in a scope nested within that of the parent.
7972 D := First_Entity (Derived_Type);
7973 while Present (D) loop
7974 if Ekind_In (D, E_Discriminant, E_Component) then
7975 if Is_Itype (Etype (D))
7976 and then Ekind (Etype (D)) = E_Anonymous_Access_Type
7978 Set_Scope (Etype (D), Current_Scope);
7985 end Build_Derived_Record_Type;
7987 ------------------------
7988 -- Build_Derived_Type --
7989 ------------------------
7991 procedure Build_Derived_Type
7993 Parent_Type : Entity_Id;
7994 Derived_Type : Entity_Id;
7995 Is_Completion : Boolean;
7996 Derive_Subps : Boolean := True)
7998 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
8001 -- Set common attributes
8003 Set_Scope (Derived_Type, Current_Scope);
8005 Set_Ekind (Derived_Type, Ekind (Parent_Base));
8006 Set_Etype (Derived_Type, Parent_Base);
8007 Set_Has_Task (Derived_Type, Has_Task (Parent_Base));
8009 Set_Size_Info (Derived_Type, Parent_Type);
8010 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
8011 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
8012 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
8014 -- If the parent type is a private subtype, the convention on the base
8015 -- type may be set in the private part, and not propagated to the
8016 -- subtype until later, so we obtain the convention from the base type.
8018 Set_Convention (Derived_Type, Convention (Parent_Base));
8020 -- Propagate invariant information. The new type has invariants if
8021 -- they are inherited from the parent type, and these invariants can
8022 -- be further inherited, so both flags are set.
8024 if Has_Inheritable_Invariants (Parent_Type) then
8025 Set_Has_Inheritable_Invariants (Derived_Type);
8026 Set_Has_Invariants (Derived_Type);
8029 -- We similarly inherit predicates
8031 if Has_Predicates (Parent_Type) then
8032 Set_Has_Predicates (Derived_Type);
8035 -- The derived type inherits the representation clauses of the parent.
8036 -- However, for a private type that is completed by a derivation, there
8037 -- may be operation attributes that have been specified already (stream
8038 -- attributes and External_Tag) and those must be provided. Finally,
8039 -- if the partial view is a private extension, the representation items
8040 -- of the parent have been inherited already, and should not be chained
8041 -- twice to the derived type.
8043 if Is_Tagged_Type (Parent_Type)
8044 and then Present (First_Rep_Item (Derived_Type))
8046 -- The existing items are either operational items or items inherited
8047 -- from a private extension declaration.
8051 -- Used to iterate over representation items of the derived type
8054 -- Last representation item of the (non-empty) representation
8055 -- item list of the derived type.
8057 Found : Boolean := False;
8060 Rep := First_Rep_Item (Derived_Type);
8062 while Present (Rep) loop
8063 if Rep = First_Rep_Item (Parent_Type) then
8068 Rep := Next_Rep_Item (Rep);
8070 if Present (Rep) then
8076 -- Here if we either encountered the parent type's first rep
8077 -- item on the derived type's rep item list (in which case
8078 -- Found is True, and we have nothing else to do), or if we
8079 -- reached the last rep item of the derived type, which is
8080 -- Last_Rep, in which case we further chain the parent type's
8081 -- rep items to those of the derived type.
8084 Set_Next_Rep_Item (Last_Rep, First_Rep_Item (Parent_Type));
8089 Set_First_Rep_Item (Derived_Type, First_Rep_Item (Parent_Type));
8092 case Ekind (Parent_Type) is
8093 when Numeric_Kind =>
8094 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
8097 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
8101 | Class_Wide_Kind =>
8102 Build_Derived_Record_Type
8103 (N, Parent_Type, Derived_Type, Derive_Subps);
8106 when Enumeration_Kind =>
8107 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
8110 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
8112 when Incomplete_Or_Private_Kind =>
8113 Build_Derived_Private_Type
8114 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
8116 -- For discriminated types, the derivation includes deriving
8117 -- primitive operations. For others it is done below.
8119 if Is_Tagged_Type (Parent_Type)
8120 or else Has_Discriminants (Parent_Type)
8121 or else (Present (Full_View (Parent_Type))
8122 and then Has_Discriminants (Full_View (Parent_Type)))
8127 when Concurrent_Kind =>
8128 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
8131 raise Program_Error;
8134 if Etype (Derived_Type) = Any_Type then
8138 -- Set delayed freeze and then derive subprograms, we need to do this
8139 -- in this order so that derived subprograms inherit the derived freeze
8142 Set_Has_Delayed_Freeze (Derived_Type);
8143 if Derive_Subps then
8144 Derive_Subprograms (Parent_Type, Derived_Type);
8147 Set_Has_Primitive_Operations
8148 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
8149 end Build_Derived_Type;
8151 -----------------------
8152 -- Build_Discriminal --
8153 -----------------------
8155 procedure Build_Discriminal (Discrim : Entity_Id) is
8156 D_Minal : Entity_Id;
8157 CR_Disc : Entity_Id;
8160 -- A discriminal has the same name as the discriminant
8162 D_Minal := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
8164 Set_Ekind (D_Minal, E_In_Parameter);
8165 Set_Mechanism (D_Minal, Default_Mechanism);
8166 Set_Etype (D_Minal, Etype (Discrim));
8167 Set_Scope (D_Minal, Current_Scope);
8169 Set_Discriminal (Discrim, D_Minal);
8170 Set_Discriminal_Link (D_Minal, Discrim);
8172 -- For task types, build at once the discriminants of the corresponding
8173 -- record, which are needed if discriminants are used in entry defaults
8174 -- and in family bounds.
8176 if Is_Concurrent_Type (Current_Scope)
8177 or else Is_Limited_Type (Current_Scope)
8179 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
8181 Set_Ekind (CR_Disc, E_In_Parameter);
8182 Set_Mechanism (CR_Disc, Default_Mechanism);
8183 Set_Etype (CR_Disc, Etype (Discrim));
8184 Set_Scope (CR_Disc, Current_Scope);
8185 Set_Discriminal_Link (CR_Disc, Discrim);
8186 Set_CR_Discriminant (Discrim, CR_Disc);
8188 end Build_Discriminal;
8190 ------------------------------------
8191 -- Build_Discriminant_Constraints --
8192 ------------------------------------
8194 function Build_Discriminant_Constraints
8197 Derived_Def : Boolean := False) return Elist_Id
8199 C : constant Node_Id := Constraint (Def);
8200 Nb_Discr : constant Nat := Number_Discriminants (T);
8202 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
8203 -- Saves the expression corresponding to a given discriminant in T
8205 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
8206 -- Return the Position number within array Discr_Expr of a discriminant
8207 -- D within the discriminant list of the discriminated type T.
8213 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
8217 Disc := First_Discriminant (T);
8218 for J in Discr_Expr'Range loop
8223 Next_Discriminant (Disc);
8226 -- Note: Since this function is called on discriminants that are
8227 -- known to belong to the discriminated type, falling through the
8228 -- loop with no match signals an internal compiler error.
8230 raise Program_Error;
8233 -- Declarations local to Build_Discriminant_Constraints
8237 Elist : constant Elist_Id := New_Elmt_List;
8245 Discrim_Present : Boolean := False;
8247 -- Start of processing for Build_Discriminant_Constraints
8250 -- The following loop will process positional associations only.
8251 -- For a positional association, the (single) discriminant is
8252 -- implicitly specified by position, in textual order (RM 3.7.2).
8254 Discr := First_Discriminant (T);
8255 Constr := First (Constraints (C));
8256 for D in Discr_Expr'Range loop
8257 exit when Nkind (Constr) = N_Discriminant_Association;
8260 Error_Msg_N ("too few discriminants given in constraint", C);
8261 return New_Elmt_List;
8263 elsif Nkind (Constr) = N_Range
8264 or else (Nkind (Constr) = N_Attribute_Reference
8266 Attribute_Name (Constr) = Name_Range)
8269 ("a range is not a valid discriminant constraint", Constr);
8270 Discr_Expr (D) := Error;
8273 Analyze_And_Resolve (Constr, Base_Type (Etype (Discr)));
8274 Discr_Expr (D) := Constr;
8277 Next_Discriminant (Discr);
8281 if No (Discr) and then Present (Constr) then
8282 Error_Msg_N ("too many discriminants given in constraint", Constr);
8283 return New_Elmt_List;
8286 -- Named associations can be given in any order, but if both positional
8287 -- and named associations are used in the same discriminant constraint,
8288 -- then positional associations must occur first, at their normal
8289 -- position. Hence once a named association is used, the rest of the
8290 -- discriminant constraint must use only named associations.
8292 while Present (Constr) loop
8294 -- Positional association forbidden after a named association
8296 if Nkind (Constr) /= N_Discriminant_Association then
8297 Error_Msg_N ("positional association follows named one", Constr);
8298 return New_Elmt_List;
8300 -- Otherwise it is a named association
8303 -- E records the type of the discriminants in the named
8304 -- association. All the discriminants specified in the same name
8305 -- association must have the same type.
8309 -- Search the list of discriminants in T to see if the simple name
8310 -- given in the constraint matches any of them.
8312 Id := First (Selector_Names (Constr));
8313 while Present (Id) loop
8316 -- If Original_Discriminant is present, we are processing a
8317 -- generic instantiation and this is an instance node. We need
8318 -- to find the name of the corresponding discriminant in the
8319 -- actual record type T and not the name of the discriminant in
8320 -- the generic formal. Example:
8323 -- type G (D : int) is private;
8325 -- subtype W is G (D => 1);
8327 -- type Rec (X : int) is record ... end record;
8328 -- package Q is new P (G => Rec);
8330 -- At the point of the instantiation, formal type G is Rec
8331 -- and therefore when reanalyzing "subtype W is G (D => 1);"
8332 -- which really looks like "subtype W is Rec (D => 1);" at
8333 -- the point of instantiation, we want to find the discriminant
8334 -- that corresponds to D in Rec, i.e. X.
8336 if Present (Original_Discriminant (Id))
8337 and then In_Instance
8339 Discr := Find_Corresponding_Discriminant (Id, T);
8343 Discr := First_Discriminant (T);
8344 while Present (Discr) loop
8345 if Chars (Discr) = Chars (Id) then
8350 Next_Discriminant (Discr);
8354 Error_Msg_N ("& does not match any discriminant", Id);
8355 return New_Elmt_List;
8357 -- If the parent type is a generic formal, preserve the
8358 -- name of the discriminant for subsequent instances.
8359 -- see comment at the beginning of this if statement.
8361 elsif Is_Generic_Type (Root_Type (T)) then
8362 Set_Original_Discriminant (Id, Discr);
8366 Position := Pos_Of_Discr (T, Discr);
8368 if Present (Discr_Expr (Position)) then
8369 Error_Msg_N ("duplicate constraint for discriminant&", Id);
8372 -- Each discriminant specified in the same named association
8373 -- must be associated with a separate copy of the
8374 -- corresponding expression.
8376 if Present (Next (Id)) then
8377 Expr := New_Copy_Tree (Expression (Constr));
8378 Set_Parent (Expr, Parent (Expression (Constr)));
8380 Expr := Expression (Constr);
8383 Discr_Expr (Position) := Expr;
8384 Analyze_And_Resolve (Expr, Base_Type (Etype (Discr)));
8387 -- A discriminant association with more than one discriminant
8388 -- name is only allowed if the named discriminants are all of
8389 -- the same type (RM 3.7.1(8)).
8392 E := Base_Type (Etype (Discr));
8394 elsif Base_Type (Etype (Discr)) /= E then
8396 ("all discriminants in an association " &
8397 "must have the same type", Id);
8407 -- A discriminant constraint must provide exactly one value for each
8408 -- discriminant of the type (RM 3.7.1(8)).
8410 for J in Discr_Expr'Range loop
8411 if No (Discr_Expr (J)) then
8412 Error_Msg_N ("too few discriminants given in constraint", C);
8413 return New_Elmt_List;
8417 -- Determine if there are discriminant expressions in the constraint
8419 for J in Discr_Expr'Range loop
8420 if Denotes_Discriminant
8421 (Discr_Expr (J), Check_Concurrent => True)
8423 Discrim_Present := True;
8427 -- Build an element list consisting of the expressions given in the
8428 -- discriminant constraint and apply the appropriate checks. The list
8429 -- is constructed after resolving any named discriminant associations
8430 -- and therefore the expressions appear in the textual order of the
8433 Discr := First_Discriminant (T);
8434 for J in Discr_Expr'Range loop
8435 if Discr_Expr (J) /= Error then
8436 Append_Elmt (Discr_Expr (J), Elist);
8438 -- If any of the discriminant constraints is given by a
8439 -- discriminant and we are in a derived type declaration we
8440 -- have a discriminant renaming. Establish link between new
8441 -- and old discriminant.
8443 if Denotes_Discriminant (Discr_Expr (J)) then
8445 Set_Corresponding_Discriminant
8446 (Entity (Discr_Expr (J)), Discr);
8449 -- Force the evaluation of non-discriminant expressions.
8450 -- If we have found a discriminant in the constraint 3.4(26)
8451 -- and 3.8(18) demand that no range checks are performed are
8452 -- after evaluation. If the constraint is for a component
8453 -- definition that has a per-object constraint, expressions are
8454 -- evaluated but not checked either. In all other cases perform
8458 if Discrim_Present then
8461 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
8463 Has_Per_Object_Constraint
8464 (Defining_Identifier (Parent (Parent (Def))))
8468 elsif Is_Access_Type (Etype (Discr)) then
8469 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
8472 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
8475 Force_Evaluation (Discr_Expr (J));
8478 -- Check that the designated type of an access discriminant's
8479 -- expression is not a class-wide type unless the discriminant's
8480 -- designated type is also class-wide.
8482 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
8483 and then not Is_Class_Wide_Type
8484 (Designated_Type (Etype (Discr)))
8485 and then Etype (Discr_Expr (J)) /= Any_Type
8486 and then Is_Class_Wide_Type
8487 (Designated_Type (Etype (Discr_Expr (J))))
8489 Wrong_Type (Discr_Expr (J), Etype (Discr));
8491 elsif Is_Access_Type (Etype (Discr))
8492 and then not Is_Access_Constant (Etype (Discr))
8493 and then Is_Access_Type (Etype (Discr_Expr (J)))
8494 and then Is_Access_Constant (Etype (Discr_Expr (J)))
8497 ("constraint for discriminant& must be access to variable",
8502 Next_Discriminant (Discr);
8506 end Build_Discriminant_Constraints;
8508 ---------------------------------
8509 -- Build_Discriminated_Subtype --
8510 ---------------------------------
8512 procedure Build_Discriminated_Subtype
8516 Related_Nod : Node_Id;
8517 For_Access : Boolean := False)
8519 Has_Discrs : constant Boolean := Has_Discriminants (T);
8520 Constrained : constant Boolean :=
8522 and then not Is_Empty_Elmt_List (Elist)
8523 and then not Is_Class_Wide_Type (T))
8524 or else Is_Constrained (T);
8527 if Ekind (T) = E_Record_Type then
8529 Set_Ekind (Def_Id, E_Private_Subtype);
8530 Set_Is_For_Access_Subtype (Def_Id, True);
8532 Set_Ekind (Def_Id, E_Record_Subtype);
8535 -- Inherit preelaboration flag from base, for types for which it
8536 -- may have been set: records, private types, protected types.
8538 Set_Known_To_Have_Preelab_Init
8539 (Def_Id, Known_To_Have_Preelab_Init (T));
8541 elsif Ekind (T) = E_Task_Type then
8542 Set_Ekind (Def_Id, E_Task_Subtype);
8544 elsif Ekind (T) = E_Protected_Type then
8545 Set_Ekind (Def_Id, E_Protected_Subtype);
8546 Set_Known_To_Have_Preelab_Init
8547 (Def_Id, Known_To_Have_Preelab_Init (T));
8549 elsif Is_Private_Type (T) then
8550 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
8551 Set_Known_To_Have_Preelab_Init
8552 (Def_Id, Known_To_Have_Preelab_Init (T));
8554 elsif Is_Class_Wide_Type (T) then
8555 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
8558 -- Incomplete type. Attach subtype to list of dependents, to be
8559 -- completed with full view of parent type, unless is it the
8560 -- designated subtype of a record component within an init_proc.
8561 -- This last case arises for a component of an access type whose
8562 -- designated type is incomplete (e.g. a Taft Amendment type).
8563 -- The designated subtype is within an inner scope, and needs no
8564 -- elaboration, because only the access type is needed in the
8565 -- initialization procedure.
8567 Set_Ekind (Def_Id, Ekind (T));
8569 if For_Access and then Within_Init_Proc then
8572 Append_Elmt (Def_Id, Private_Dependents (T));
8576 Set_Etype (Def_Id, T);
8577 Init_Size_Align (Def_Id);
8578 Set_Has_Discriminants (Def_Id, Has_Discrs);
8579 Set_Is_Constrained (Def_Id, Constrained);
8581 Set_First_Entity (Def_Id, First_Entity (T));
8582 Set_Last_Entity (Def_Id, Last_Entity (T));
8584 -- If the subtype is the completion of a private declaration, there may
8585 -- have been representation clauses for the partial view, and they must
8586 -- be preserved. Build_Derived_Type chains the inherited clauses with
8587 -- the ones appearing on the extension. If this comes from a subtype
8588 -- declaration, all clauses are inherited.
8590 if No (First_Rep_Item (Def_Id)) then
8591 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
8594 if Is_Tagged_Type (T) then
8595 Set_Is_Tagged_Type (Def_Id);
8596 Make_Class_Wide_Type (Def_Id);
8599 Set_Stored_Constraint (Def_Id, No_Elist);
8602 Set_Discriminant_Constraint (Def_Id, Elist);
8603 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
8606 if Is_Tagged_Type (T) then
8608 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
8609 -- concurrent record type (which has the list of primitive
8612 if Ada_Version >= Ada_2005
8613 and then Is_Concurrent_Type (T)
8615 Set_Corresponding_Record_Type (Def_Id,
8616 Corresponding_Record_Type (T));
8618 Set_Direct_Primitive_Operations (Def_Id,
8619 Direct_Primitive_Operations (T));
8622 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
8625 -- Subtypes introduced by component declarations do not need to be
8626 -- marked as delayed, and do not get freeze nodes, because the semantics
8627 -- verifies that the parents of the subtypes are frozen before the
8628 -- enclosing record is frozen.
8630 if not Is_Type (Scope (Def_Id)) then
8631 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
8633 if Is_Private_Type (T)
8634 and then Present (Full_View (T))
8636 Conditional_Delay (Def_Id, Full_View (T));
8638 Conditional_Delay (Def_Id, T);
8642 if Is_Record_Type (T) then
8643 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
8646 and then not Is_Empty_Elmt_List (Elist)
8647 and then not For_Access
8649 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
8650 elsif not For_Access then
8651 Set_Cloned_Subtype (Def_Id, T);
8654 end Build_Discriminated_Subtype;
8656 ---------------------------
8657 -- Build_Itype_Reference --
8658 ---------------------------
8660 procedure Build_Itype_Reference
8664 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
8667 -- Itype references are only created for use by the back-end
8669 if Inside_A_Generic then
8672 Set_Itype (IR, Ityp);
8673 Insert_After (Nod, IR);
8675 end Build_Itype_Reference;
8677 ------------------------
8678 -- Build_Scalar_Bound --
8679 ------------------------
8681 function Build_Scalar_Bound
8684 Der_T : Entity_Id) return Node_Id
8686 New_Bound : Entity_Id;
8689 -- Note: not clear why this is needed, how can the original bound
8690 -- be unanalyzed at this point? and if it is, what business do we
8691 -- have messing around with it? and why is the base type of the
8692 -- parent type the right type for the resolution. It probably is
8693 -- not! It is OK for the new bound we are creating, but not for
8694 -- the old one??? Still if it never happens, no problem!
8696 Analyze_And_Resolve (Bound, Base_Type (Par_T));
8698 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
8699 New_Bound := New_Copy (Bound);
8700 Set_Etype (New_Bound, Der_T);
8701 Set_Analyzed (New_Bound);
8703 elsif Is_Entity_Name (Bound) then
8704 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
8706 -- The following is almost certainly wrong. What business do we have
8707 -- relocating a node (Bound) that is presumably still attached to
8708 -- the tree elsewhere???
8711 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
8714 Set_Etype (New_Bound, Der_T);
8716 end Build_Scalar_Bound;
8718 --------------------------------
8719 -- Build_Underlying_Full_View --
8720 --------------------------------
8722 procedure Build_Underlying_Full_View
8727 Loc : constant Source_Ptr := Sloc (N);
8728 Subt : constant Entity_Id :=
8729 Make_Defining_Identifier
8730 (Loc, New_External_Name (Chars (Typ), 'S'));
8737 procedure Set_Discriminant_Name (Id : Node_Id);
8738 -- If the derived type has discriminants, they may rename discriminants
8739 -- of the parent. When building the full view of the parent, we need to
8740 -- recover the names of the original discriminants if the constraint is
8741 -- given by named associations.
8743 ---------------------------
8744 -- Set_Discriminant_Name --
8745 ---------------------------
8747 procedure Set_Discriminant_Name (Id : Node_Id) is
8751 Set_Original_Discriminant (Id, Empty);
8753 if Has_Discriminants (Typ) then
8754 Disc := First_Discriminant (Typ);
8755 while Present (Disc) loop
8756 if Chars (Disc) = Chars (Id)
8757 and then Present (Corresponding_Discriminant (Disc))
8759 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
8761 Next_Discriminant (Disc);
8764 end Set_Discriminant_Name;
8766 -- Start of processing for Build_Underlying_Full_View
8769 if Nkind (N) = N_Full_Type_Declaration then
8770 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
8772 elsif Nkind (N) = N_Subtype_Declaration then
8773 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
8775 elsif Nkind (N) = N_Component_Declaration then
8778 (Constraint (Subtype_Indication (Component_Definition (N))));
8781 raise Program_Error;
8784 C := First (Constraints (Constr));
8785 while Present (C) loop
8786 if Nkind (C) = N_Discriminant_Association then
8787 Id := First (Selector_Names (C));
8788 while Present (Id) loop
8789 Set_Discriminant_Name (Id);
8798 Make_Subtype_Declaration (Loc,
8799 Defining_Identifier => Subt,
8800 Subtype_Indication =>
8801 Make_Subtype_Indication (Loc,
8802 Subtype_Mark => New_Reference_To (Par, Loc),
8803 Constraint => New_Copy_Tree (Constr)));
8805 -- If this is a component subtype for an outer itype, it is not
8806 -- a list member, so simply set the parent link for analysis: if
8807 -- the enclosing type does not need to be in a declarative list,
8808 -- neither do the components.
8810 if Is_List_Member (N)
8811 and then Nkind (N) /= N_Component_Declaration
8813 Insert_Before (N, Indic);
8815 Set_Parent (Indic, Parent (N));
8819 Set_Underlying_Full_View (Typ, Full_View (Subt));
8820 end Build_Underlying_Full_View;
8822 -------------------------------
8823 -- Check_Abstract_Overriding --
8824 -------------------------------
8826 procedure Check_Abstract_Overriding (T : Entity_Id) is
8827 Alias_Subp : Entity_Id;
8833 procedure Check_Pragma_Implemented (Subp : Entity_Id);
8834 -- Ada 2012 (AI05-0030): Subprogram Subp overrides an interface routine
8835 -- which has pragma Implemented already set. Check whether Subp's entity
8836 -- kind conforms to the implementation kind of the overridden routine.
8838 procedure Check_Pragma_Implemented
8840 Iface_Subp : Entity_Id);
8841 -- Ada 2012 (AI05-0030): Subprogram Subp overrides interface routine
8842 -- Iface_Subp and both entities have pragma Implemented already set on
8843 -- them. Check whether the two implementation kinds are conforming.
8845 procedure Inherit_Pragma_Implemented
8847 Iface_Subp : Entity_Id);
8848 -- Ada 2012 (AI05-0030): Interface primitive Subp overrides interface
8849 -- subprogram Iface_Subp which has been marked by pragma Implemented.
8850 -- Propagate the implementation kind of Iface_Subp to Subp.
8852 ------------------------------
8853 -- Check_Pragma_Implemented --
8854 ------------------------------
8856 procedure Check_Pragma_Implemented (Subp : Entity_Id) is
8857 Iface_Alias : constant Entity_Id := Interface_Alias (Subp);
8858 Impl_Kind : constant Name_Id := Implementation_Kind (Iface_Alias);
8859 Contr_Typ : Entity_Id;
8862 -- Subp must have an alias since it is a hidden entity used to link
8863 -- an interface subprogram to its overriding counterpart.
8865 pragma Assert (Present (Alias (Subp)));
8867 -- Extract the type of the controlling formal
8869 Contr_Typ := Etype (First_Formal (Alias (Subp)));
8871 if Is_Concurrent_Record_Type (Contr_Typ) then
8872 Contr_Typ := Corresponding_Concurrent_Type (Contr_Typ);
8875 -- An interface subprogram whose implementation kind is By_Entry must
8876 -- be implemented by an entry.
8878 if Impl_Kind = Name_By_Entry
8879 and then Ekind (Wrapped_Entity (Alias (Subp))) /= E_Entry
8881 Error_Msg_Node_2 := Iface_Alias;
8883 ("type & must implement abstract subprogram & with an entry",
8884 Alias (Subp), Contr_Typ);
8886 elsif Impl_Kind = Name_By_Protected_Procedure then
8888 -- An interface subprogram whose implementation kind is By_
8889 -- Protected_Procedure cannot be implemented by a primitive
8890 -- procedure of a task type.
8892 if Ekind (Contr_Typ) /= E_Protected_Type then
8893 Error_Msg_Node_2 := Contr_Typ;
8895 ("interface subprogram & cannot be implemented by a " &
8896 "primitive procedure of task type &", Alias (Subp),
8899 -- An interface subprogram whose implementation kind is By_
8900 -- Protected_Procedure must be implemented by a procedure.
8902 elsif Is_Primitive_Wrapper (Alias (Subp))
8903 and then Ekind (Wrapped_Entity (Alias (Subp))) /= E_Procedure
8905 Error_Msg_Node_2 := Iface_Alias;
8907 ("type & must implement abstract subprogram & with a " &
8908 "procedure", Alias (Subp), Contr_Typ);
8911 end Check_Pragma_Implemented;
8913 ------------------------------
8914 -- Check_Pragma_Implemented --
8915 ------------------------------
8917 procedure Check_Pragma_Implemented
8919 Iface_Subp : Entity_Id)
8921 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
8922 Subp_Kind : constant Name_Id := Implementation_Kind (Subp);
8925 -- Ada 2012 (AI05-0030): The implementation kinds of an overridden
8926 -- and overriding subprogram are different. In general this is an
8927 -- error except when the implementation kind of the overridden
8928 -- subprograms is By_Any.
8930 if Iface_Kind /= Subp_Kind
8931 and then Iface_Kind /= Name_By_Any
8933 if Iface_Kind = Name_By_Entry then
8935 ("incompatible implementation kind, overridden subprogram " &
8936 "is marked By_Entry", Subp);
8939 ("incompatible implementation kind, overridden subprogram " &
8940 "is marked By_Protected_Procedure", Subp);
8943 end Check_Pragma_Implemented;
8945 --------------------------------
8946 -- Inherit_Pragma_Implemented --
8947 --------------------------------
8949 procedure Inherit_Pragma_Implemented
8951 Iface_Subp : Entity_Id)
8953 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
8954 Loc : constant Source_Ptr := Sloc (Subp);
8955 Impl_Prag : Node_Id;
8958 -- Since the implementation kind is stored as a representation item
8959 -- rather than a flag, create a pragma node.
8963 Chars => Name_Implemented,
8964 Pragma_Argument_Associations => New_List (
8965 Make_Pragma_Argument_Association (Loc,
8967 New_Reference_To (Subp, Loc)),
8969 Make_Pragma_Argument_Association (Loc,
8970 Expression => Make_Identifier (Loc, Iface_Kind))));
8972 -- The pragma doesn't need to be analyzed because it is internally
8973 -- build. It is safe to directly register it as a rep item since we
8974 -- are only interested in the characters of the implementation kind.
8976 Record_Rep_Item (Subp, Impl_Prag);
8977 end Inherit_Pragma_Implemented;
8979 -- Start of processing for Check_Abstract_Overriding
8982 Op_List := Primitive_Operations (T);
8984 -- Loop to check primitive operations
8986 Elmt := First_Elmt (Op_List);
8987 while Present (Elmt) loop
8988 Subp := Node (Elmt);
8989 Alias_Subp := Alias (Subp);
8991 -- Inherited subprograms are identified by the fact that they do not
8992 -- come from source, and the associated source location is the
8993 -- location of the first subtype of the derived type.
8995 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
8996 -- subprograms that "require overriding".
8998 -- Special exception, do not complain about failure to override the
8999 -- stream routines _Input and _Output, as well as the primitive
9000 -- operations used in dispatching selects since we always provide
9001 -- automatic overridings for these subprograms.
9003 -- Also ignore this rule for convention CIL since .NET libraries
9004 -- do bizarre things with interfaces???
9006 -- The partial view of T may have been a private extension, for
9007 -- which inherited functions dispatching on result are abstract.
9008 -- If the full view is a null extension, there is no need for
9009 -- overriding in Ada2005, but wrappers need to be built for them
9010 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
9012 if Is_Null_Extension (T)
9013 and then Has_Controlling_Result (Subp)
9014 and then Ada_Version >= Ada_2005
9015 and then Present (Alias_Subp)
9016 and then not Comes_From_Source (Subp)
9017 and then not Is_Abstract_Subprogram (Alias_Subp)
9018 and then not Is_Access_Type (Etype (Subp))
9022 -- Ada 2005 (AI-251): Internal entities of interfaces need no
9023 -- processing because this check is done with the aliased
9026 elsif Present (Interface_Alias (Subp)) then
9029 elsif (Is_Abstract_Subprogram (Subp)
9030 or else Requires_Overriding (Subp)
9032 (Has_Controlling_Result (Subp)
9033 and then Present (Alias_Subp)
9034 and then not Comes_From_Source (Subp)
9035 and then Sloc (Subp) = Sloc (First_Subtype (T))))
9036 and then not Is_TSS (Subp, TSS_Stream_Input)
9037 and then not Is_TSS (Subp, TSS_Stream_Output)
9038 and then not Is_Abstract_Type (T)
9039 and then Convention (T) /= Convention_CIL
9040 and then not Is_Predefined_Interface_Primitive (Subp)
9042 -- Ada 2005 (AI-251): Do not consider hidden entities associated
9043 -- with abstract interface types because the check will be done
9044 -- with the aliased entity (otherwise we generate a duplicated
9047 and then not Present (Interface_Alias (Subp))
9049 if Present (Alias_Subp) then
9051 -- Only perform the check for a derived subprogram when the
9052 -- type has an explicit record extension. This avoids incorrect
9053 -- flagging of abstract subprograms for the case of a type
9054 -- without an extension that is derived from a formal type
9055 -- with a tagged actual (can occur within a private part).
9057 -- Ada 2005 (AI-391): In the case of an inherited function with
9058 -- a controlling result of the type, the rule does not apply if
9059 -- the type is a null extension (unless the parent function
9060 -- itself is abstract, in which case the function must still be
9061 -- be overridden). The expander will generate an overriding
9062 -- wrapper function calling the parent subprogram (see
9063 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
9065 Type_Def := Type_Definition (Parent (T));
9067 if Nkind (Type_Def) = N_Derived_Type_Definition
9068 and then Present (Record_Extension_Part (Type_Def))
9070 (Ada_Version < Ada_2005
9071 or else not Is_Null_Extension (T)
9072 or else Ekind (Subp) = E_Procedure
9073 or else not Has_Controlling_Result (Subp)
9074 or else Is_Abstract_Subprogram (Alias_Subp)
9075 or else Requires_Overriding (Subp)
9076 or else Is_Access_Type (Etype (Subp)))
9078 -- Avoid reporting error in case of abstract predefined
9079 -- primitive inherited from interface type because the
9080 -- body of internally generated predefined primitives
9081 -- of tagged types are generated later by Freeze_Type
9083 if Is_Interface (Root_Type (T))
9084 and then Is_Abstract_Subprogram (Subp)
9085 and then Is_Predefined_Dispatching_Operation (Subp)
9086 and then not Comes_From_Source (Ultimate_Alias (Subp))
9092 ("type must be declared abstract or & overridden",
9095 -- Traverse the whole chain of aliased subprograms to
9096 -- complete the error notification. This is especially
9097 -- useful for traceability of the chain of entities when
9098 -- the subprogram corresponds with an interface
9099 -- subprogram (which may be defined in another package).
9101 if Present (Alias_Subp) then
9107 while Present (Alias (E)) loop
9108 Error_Msg_Sloc := Sloc (E);
9110 ("\& has been inherited #", T, Subp);
9114 Error_Msg_Sloc := Sloc (E);
9116 ("\& has been inherited from subprogram #",
9122 -- Ada 2005 (AI-345): Protected or task type implementing
9123 -- abstract interfaces.
9125 elsif Is_Concurrent_Record_Type (T)
9126 and then Present (Interfaces (T))
9128 -- The controlling formal of Subp must be of mode "out",
9129 -- "in out" or an access-to-variable to be overridden.
9131 -- Error message below needs rewording (remember comma
9132 -- in -gnatj mode) ???
9134 if Ekind (First_Formal (Subp)) = E_In_Parameter
9135 and then Ekind (Subp) /= E_Function
9137 if not Is_Predefined_Dispatching_Operation (Subp) then
9139 ("first formal of & must be of mode `OUT`, " &
9140 "`IN OUT` or access-to-variable", T, Subp);
9142 ("\to be overridden by protected procedure or " &
9143 "entry (RM 9.4(11.9/2))", T);
9146 -- Some other kind of overriding failure
9150 ("interface subprogram & must be overridden",
9153 -- Examine primitive operations of synchronized type,
9154 -- to find homonyms that have the wrong profile.
9161 First_Entity (Corresponding_Concurrent_Type (T));
9162 while Present (Prim) loop
9163 if Chars (Prim) = Chars (Subp) then
9165 ("profile is not type conformant with "
9166 & "prefixed view profile of "
9167 & "inherited operation&", Prim, Subp);
9177 Error_Msg_Node_2 := T;
9179 ("abstract subprogram& not allowed for type&", Subp);
9181 -- Also post unconditional warning on the type (unconditional
9182 -- so that if there are more than one of these cases, we get
9183 -- them all, and not just the first one).
9185 Error_Msg_Node_2 := Subp;
9186 Error_Msg_N ("nonabstract type& has abstract subprogram&!", T);
9190 -- Ada 2012 (AI05-0030): Perform some checks related to pragma
9193 -- Subp is an expander-generated procedure which maps an interface
9194 -- alias to a protected wrapper. The interface alias is flagged by
9195 -- pragma Implemented. Ensure that Subp is a procedure when the
9196 -- implementation kind is By_Protected_Procedure or an entry when
9199 if Ada_Version >= Ada_2012
9200 and then Is_Hidden (Subp)
9201 and then Present (Interface_Alias (Subp))
9202 and then Has_Rep_Pragma (Interface_Alias (Subp), Name_Implemented)
9204 Check_Pragma_Implemented (Subp);
9207 -- Subp is an interface primitive which overrides another interface
9208 -- primitive marked with pragma Implemented.
9210 if Ada_Version >= Ada_2012
9211 and then Present (Overridden_Operation (Subp))
9212 and then Has_Rep_Pragma
9213 (Overridden_Operation (Subp), Name_Implemented)
9215 -- If the overriding routine is also marked by Implemented, check
9216 -- that the two implementation kinds are conforming.
9218 if Has_Rep_Pragma (Subp, Name_Implemented) then
9219 Check_Pragma_Implemented
9221 Iface_Subp => Overridden_Operation (Subp));
9223 -- Otherwise the overriding routine inherits the implementation
9224 -- kind from the overridden subprogram.
9227 Inherit_Pragma_Implemented
9229 Iface_Subp => Overridden_Operation (Subp));
9235 end Check_Abstract_Overriding;
9237 ------------------------------------------------
9238 -- Check_Access_Discriminant_Requires_Limited --
9239 ------------------------------------------------
9241 procedure Check_Access_Discriminant_Requires_Limited
9246 -- A discriminant_specification for an access discriminant shall appear
9247 -- only in the declaration for a task or protected type, or for a type
9248 -- with the reserved word 'limited' in its definition or in one of its
9249 -- ancestors (RM 3.7(10)).
9251 -- AI-0063: The proper condition is that type must be immutably limited,
9252 -- or else be a partial view.
9254 if Nkind (Discriminant_Type (D)) = N_Access_Definition then
9255 if Is_Immutably_Limited_Type (Current_Scope)
9257 (Nkind (Parent (Current_Scope)) = N_Private_Type_Declaration
9258 and then Limited_Present (Parent (Current_Scope)))
9264 ("access discriminants allowed only for limited types", Loc);
9267 end Check_Access_Discriminant_Requires_Limited;
9269 -----------------------------------
9270 -- Check_Aliased_Component_Types --
9271 -----------------------------------
9273 procedure Check_Aliased_Component_Types (T : Entity_Id) is
9277 -- ??? Also need to check components of record extensions, but not
9278 -- components of protected types (which are always limited).
9280 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
9281 -- types to be unconstrained. This is safe because it is illegal to
9282 -- create access subtypes to such types with explicit discriminant
9285 if not Is_Limited_Type (T) then
9286 if Ekind (T) = E_Record_Type then
9287 C := First_Component (T);
9288 while Present (C) loop
9290 and then Has_Discriminants (Etype (C))
9291 and then not Is_Constrained (Etype (C))
9292 and then not In_Instance_Body
9293 and then Ada_Version < Ada_2005
9296 ("aliased component must be constrained (RM 3.6(11))",
9303 elsif Ekind (T) = E_Array_Type then
9304 if Has_Aliased_Components (T)
9305 and then Has_Discriminants (Component_Type (T))
9306 and then not Is_Constrained (Component_Type (T))
9307 and then not In_Instance_Body
9308 and then Ada_Version < Ada_2005
9311 ("aliased component type must be constrained (RM 3.6(11))",
9316 end Check_Aliased_Component_Types;
9318 ----------------------
9319 -- Check_Completion --
9320 ----------------------
9322 procedure Check_Completion (Body_Id : Node_Id := Empty) is
9325 procedure Post_Error;
9326 -- Post error message for lack of completion for entity E
9332 procedure Post_Error is
9334 procedure Missing_Body;
9335 -- Output missing body message
9341 procedure Missing_Body is
9343 -- Spec is in same unit, so we can post on spec
9345 if In_Same_Source_Unit (Body_Id, E) then
9346 Error_Msg_N ("missing body for &", E);
9348 -- Spec is in a separate unit, so we have to post on the body
9351 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
9355 -- Start of processing for Post_Error
9358 if not Comes_From_Source (E) then
9360 if Ekind_In (E, E_Task_Type, E_Protected_Type) then
9361 -- It may be an anonymous protected type created for a
9362 -- single variable. Post error on variable, if present.
9368 Var := First_Entity (Current_Scope);
9369 while Present (Var) loop
9370 exit when Etype (Var) = E
9371 and then Comes_From_Source (Var);
9376 if Present (Var) then
9383 -- If a generated entity has no completion, then either previous
9384 -- semantic errors have disabled the expansion phase, or else we had
9385 -- missing subunits, or else we are compiling without expansion,
9386 -- or else something is very wrong.
9388 if not Comes_From_Source (E) then
9390 (Serious_Errors_Detected > 0
9391 or else Configurable_Run_Time_Violations > 0
9392 or else Subunits_Missing
9393 or else not Expander_Active);
9396 -- Here for source entity
9399 -- Here if no body to post the error message, so we post the error
9400 -- on the declaration that has no completion. This is not really
9401 -- the right place to post it, think about this later ???
9403 if No (Body_Id) then
9406 ("missing full declaration for }", Parent (E), E);
9408 Error_Msg_NE ("missing body for &", Parent (E), E);
9411 -- Package body has no completion for a declaration that appears
9412 -- in the corresponding spec. Post error on the body, with a
9413 -- reference to the non-completed declaration.
9416 Error_Msg_Sloc := Sloc (E);
9419 Error_Msg_NE ("missing full declaration for }!", Body_Id, E);
9421 elsif Is_Overloadable (E)
9422 and then Current_Entity_In_Scope (E) /= E
9424 -- It may be that the completion is mistyped and appears as
9425 -- a distinct overloading of the entity.
9428 Candidate : constant Entity_Id :=
9429 Current_Entity_In_Scope (E);
9430 Decl : constant Node_Id :=
9431 Unit_Declaration_Node (Candidate);
9434 if Is_Overloadable (Candidate)
9435 and then Ekind (Candidate) = Ekind (E)
9436 and then Nkind (Decl) = N_Subprogram_Body
9437 and then Acts_As_Spec (Decl)
9439 Check_Type_Conformant (Candidate, E);
9453 -- Start of processing for Check_Completion
9456 E := First_Entity (Current_Scope);
9457 while Present (E) loop
9458 if Is_Intrinsic_Subprogram (E) then
9461 -- The following situation requires special handling: a child unit
9462 -- that appears in the context clause of the body of its parent:
9464 -- procedure Parent.Child (...);
9466 -- with Parent.Child;
9467 -- package body Parent is
9469 -- Here Parent.Child appears as a local entity, but should not be
9470 -- flagged as requiring completion, because it is a compilation
9473 -- Ignore missing completion for a subprogram that does not come from
9474 -- source (including the _Call primitive operation of RAS types,
9475 -- which has to have the flag Comes_From_Source for other purposes):
9476 -- we assume that the expander will provide the missing completion.
9477 -- In case of previous errors, other expansion actions that provide
9478 -- bodies for null procedures with not be invoked, so inhibit message
9480 -- Note that E_Operator is not in the list that follows, because
9481 -- this kind is reserved for predefined operators, that are
9482 -- intrinsic and do not need completion.
9484 elsif Ekind (E) = E_Function
9485 or else Ekind (E) = E_Procedure
9486 or else Ekind (E) = E_Generic_Function
9487 or else Ekind (E) = E_Generic_Procedure
9489 if Has_Completion (E) then
9492 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
9495 elsif Is_Subprogram (E)
9496 and then (not Comes_From_Source (E)
9497 or else Chars (E) = Name_uCall)
9502 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
9506 elsif Nkind (Parent (E)) = N_Procedure_Specification
9507 and then Null_Present (Parent (E))
9508 and then Serious_Errors_Detected > 0
9516 elsif Is_Entry (E) then
9517 if not Has_Completion (E) and then
9518 (Ekind (Scope (E)) = E_Protected_Object
9519 or else Ekind (Scope (E)) = E_Protected_Type)
9524 elsif Is_Package_Or_Generic_Package (E) then
9525 if Unit_Requires_Body (E) then
9526 if not Has_Completion (E)
9527 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
9533 elsif not Is_Child_Unit (E) then
9534 May_Need_Implicit_Body (E);
9537 elsif Ekind (E) = E_Incomplete_Type
9538 and then No (Underlying_Type (E))
9542 elsif (Ekind (E) = E_Task_Type or else
9543 Ekind (E) = E_Protected_Type)
9544 and then not Has_Completion (E)
9548 -- A single task declared in the current scope is a constant, verify
9549 -- that the body of its anonymous type is in the same scope. If the
9550 -- task is defined elsewhere, this may be a renaming declaration for
9551 -- which no completion is needed.
9553 elsif Ekind (E) = E_Constant
9554 and then Ekind (Etype (E)) = E_Task_Type
9555 and then not Has_Completion (Etype (E))
9556 and then Scope (Etype (E)) = Current_Scope
9560 elsif Ekind (E) = E_Protected_Object
9561 and then not Has_Completion (Etype (E))
9565 elsif Ekind (E) = E_Record_Type then
9566 if Is_Tagged_Type (E) then
9567 Check_Abstract_Overriding (E);
9568 Check_Conventions (E);
9571 Check_Aliased_Component_Types (E);
9573 elsif Ekind (E) = E_Array_Type then
9574 Check_Aliased_Component_Types (E);
9580 end Check_Completion;
9582 ----------------------------
9583 -- Check_Delta_Expression --
9584 ----------------------------
9586 procedure Check_Delta_Expression (E : Node_Id) is
9588 if not (Is_Real_Type (Etype (E))) then
9589 Wrong_Type (E, Any_Real);
9591 elsif not Is_OK_Static_Expression (E) then
9592 Flag_Non_Static_Expr
9593 ("non-static expression used for delta value!", E);
9595 elsif not UR_Is_Positive (Expr_Value_R (E)) then
9596 Error_Msg_N ("delta expression must be positive", E);
9602 -- If any of above errors occurred, then replace the incorrect
9603 -- expression by the real 0.1, which should prevent further errors.
9606 Make_Real_Literal (Sloc (E), Ureal_Tenth));
9607 Analyze_And_Resolve (E, Standard_Float);
9608 end Check_Delta_Expression;
9610 -----------------------------
9611 -- Check_Digits_Expression --
9612 -----------------------------
9614 procedure Check_Digits_Expression (E : Node_Id) is
9616 if not (Is_Integer_Type (Etype (E))) then
9617 Wrong_Type (E, Any_Integer);
9619 elsif not Is_OK_Static_Expression (E) then
9620 Flag_Non_Static_Expr
9621 ("non-static expression used for digits value!", E);
9623 elsif Expr_Value (E) <= 0 then
9624 Error_Msg_N ("digits value must be greater than zero", E);
9630 -- If any of above errors occurred, then replace the incorrect
9631 -- expression by the integer 1, which should prevent further errors.
9633 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
9634 Analyze_And_Resolve (E, Standard_Integer);
9636 end Check_Digits_Expression;
9638 --------------------------
9639 -- Check_Initialization --
9640 --------------------------
9642 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
9644 if Is_Limited_Type (T)
9645 and then not In_Instance
9646 and then not In_Inlined_Body
9648 if not OK_For_Limited_Init (T, Exp) then
9650 -- In GNAT mode, this is just a warning, to allow it to be evilly
9651 -- turned off. Otherwise it is a real error.
9655 ("?cannot initialize entities of limited type!", Exp);
9657 elsif Ada_Version < Ada_2005 then
9659 ("cannot initialize entities of limited type", Exp);
9660 Explain_Limited_Type (T, Exp);
9663 -- Specialize error message according to kind of illegal
9664 -- initial expression.
9666 if Nkind (Exp) = N_Type_Conversion
9667 and then Nkind (Expression (Exp)) = N_Function_Call
9670 ("illegal context for call"
9671 & " to function with limited result", Exp);
9675 ("initialization of limited object requires aggregate "
9676 & "or function call", Exp);
9681 end Check_Initialization;
9683 ----------------------
9684 -- Check_Interfaces --
9685 ----------------------
9687 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
9688 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
9691 Iface_Def : Node_Id;
9692 Iface_Typ : Entity_Id;
9693 Parent_Node : Node_Id;
9695 Is_Task : Boolean := False;
9696 -- Set True if parent type or any progenitor is a task interface
9698 Is_Protected : Boolean := False;
9699 -- Set True if parent type or any progenitor is a protected interface
9701 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
9702 -- Check that a progenitor is compatible with declaration.
9703 -- Error is posted on Error_Node.
9709 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
9710 Iface_Id : constant Entity_Id :=
9711 Defining_Identifier (Parent (Iface_Def));
9715 if Nkind (N) = N_Private_Extension_Declaration then
9718 Type_Def := Type_Definition (N);
9721 if Is_Task_Interface (Iface_Id) then
9724 elsif Is_Protected_Interface (Iface_Id) then
9725 Is_Protected := True;
9728 if Is_Synchronized_Interface (Iface_Id) then
9730 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
9731 -- extension derived from a synchronized interface must explicitly
9732 -- be declared synchronized, because the full view will be a
9733 -- synchronized type.
9735 if Nkind (N) = N_Private_Extension_Declaration then
9736 if not Synchronized_Present (N) then
9738 ("private extension of& must be explicitly synchronized",
9742 -- However, by 3.9.4(16/2), a full type that is a record extension
9743 -- is never allowed to derive from a synchronized interface (note
9744 -- that interfaces must be excluded from this check, because those
9745 -- are represented by derived type definitions in some cases).
9747 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
9748 and then not Interface_Present (Type_Definition (N))
9750 Error_Msg_N ("record extension cannot derive from synchronized"
9751 & " interface", Error_Node);
9755 -- Check that the characteristics of the progenitor are compatible
9756 -- with the explicit qualifier in the declaration.
9757 -- The check only applies to qualifiers that come from source.
9758 -- Limited_Present also appears in the declaration of corresponding
9759 -- records, and the check does not apply to them.
9761 if Limited_Present (Type_Def)
9763 Is_Concurrent_Record_Type (Defining_Identifier (N))
9765 if Is_Limited_Interface (Parent_Type)
9766 and then not Is_Limited_Interface (Iface_Id)
9769 ("progenitor& must be limited interface",
9770 Error_Node, Iface_Id);
9773 (Task_Present (Iface_Def)
9774 or else Protected_Present (Iface_Def)
9775 or else Synchronized_Present (Iface_Def))
9776 and then Nkind (N) /= N_Private_Extension_Declaration
9777 and then not Error_Posted (N)
9780 ("progenitor& must be limited interface",
9781 Error_Node, Iface_Id);
9784 -- Protected interfaces can only inherit from limited, synchronized
9785 -- or protected interfaces.
9787 elsif Nkind (N) = N_Full_Type_Declaration
9788 and then Protected_Present (Type_Def)
9790 if Limited_Present (Iface_Def)
9791 or else Synchronized_Present (Iface_Def)
9792 or else Protected_Present (Iface_Def)
9796 elsif Task_Present (Iface_Def) then
9797 Error_Msg_N ("(Ada 2005) protected interface cannot inherit"
9798 & " from task interface", Error_Node);
9801 Error_Msg_N ("(Ada 2005) protected interface cannot inherit"
9802 & " from non-limited interface", Error_Node);
9805 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
9806 -- limited and synchronized.
9808 elsif Synchronized_Present (Type_Def) then
9809 if Limited_Present (Iface_Def)
9810 or else Synchronized_Present (Iface_Def)
9814 elsif Protected_Present (Iface_Def)
9815 and then Nkind (N) /= N_Private_Extension_Declaration
9817 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9818 & " from protected interface", Error_Node);
9820 elsif Task_Present (Iface_Def)
9821 and then Nkind (N) /= N_Private_Extension_Declaration
9823 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9824 & " from task interface", Error_Node);
9826 elsif not Is_Limited_Interface (Iface_Id) then
9827 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9828 & " from non-limited interface", Error_Node);
9831 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
9832 -- synchronized or task interfaces.
9834 elsif Nkind (N) = N_Full_Type_Declaration
9835 and then Task_Present (Type_Def)
9837 if Limited_Present (Iface_Def)
9838 or else Synchronized_Present (Iface_Def)
9839 or else Task_Present (Iface_Def)
9843 elsif Protected_Present (Iface_Def) then
9844 Error_Msg_N ("(Ada 2005) task interface cannot inherit from"
9845 & " protected interface", Error_Node);
9848 Error_Msg_N ("(Ada 2005) task interface cannot inherit from"
9849 & " non-limited interface", Error_Node);
9854 -- Start of processing for Check_Interfaces
9857 if Is_Interface (Parent_Type) then
9858 if Is_Task_Interface (Parent_Type) then
9861 elsif Is_Protected_Interface (Parent_Type) then
9862 Is_Protected := True;
9866 if Nkind (N) = N_Private_Extension_Declaration then
9868 -- Check that progenitors are compatible with declaration
9870 Iface := First (Interface_List (Def));
9871 while Present (Iface) loop
9872 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
9874 Parent_Node := Parent (Base_Type (Iface_Typ));
9875 Iface_Def := Type_Definition (Parent_Node);
9877 if not Is_Interface (Iface_Typ) then
9878 Diagnose_Interface (Iface, Iface_Typ);
9881 Check_Ifaces (Iface_Def, Iface);
9887 if Is_Task and Is_Protected then
9889 ("type cannot derive from task and protected interface", N);
9895 -- Full type declaration of derived type.
9896 -- Check compatibility with parent if it is interface type
9898 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
9899 and then Is_Interface (Parent_Type)
9901 Parent_Node := Parent (Parent_Type);
9903 -- More detailed checks for interface varieties
9906 (Iface_Def => Type_Definition (Parent_Node),
9907 Error_Node => Subtype_Indication (Type_Definition (N)));
9910 Iface := First (Interface_List (Def));
9911 while Present (Iface) loop
9912 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
9914 Parent_Node := Parent (Base_Type (Iface_Typ));
9915 Iface_Def := Type_Definition (Parent_Node);
9917 if not Is_Interface (Iface_Typ) then
9918 Diagnose_Interface (Iface, Iface_Typ);
9921 -- "The declaration of a specific descendant of an interface
9922 -- type freezes the interface type" RM 13.14
9924 Freeze_Before (N, Iface_Typ);
9925 Check_Ifaces (Iface_Def, Error_Node => Iface);
9931 if Is_Task and Is_Protected then
9933 ("type cannot derive from task and protected interface", N);
9935 end Check_Interfaces;
9937 ------------------------------------
9938 -- Check_Or_Process_Discriminants --
9939 ------------------------------------
9941 -- If an incomplete or private type declaration was already given for the
9942 -- type, the discriminants may have already been processed if they were
9943 -- present on the incomplete declaration. In this case a full conformance
9944 -- check has been performed in Find_Type_Name, and we then recheck here
9945 -- some properties that can't be checked on the partial view alone.
9946 -- Otherwise we call Process_Discriminants.
9948 procedure Check_Or_Process_Discriminants
9951 Prev : Entity_Id := Empty)
9954 if Has_Discriminants (T) then
9956 -- Discriminants are already set on T if they were already present
9957 -- on the partial view. Make them visible to component declarations.
9961 -- Discriminant on T (full view) referencing expr on partial view
9964 -- Entity of corresponding discriminant on partial view
9967 -- Discriminant specification for full view, expression is the
9968 -- syntactic copy on full view (which has been checked for
9969 -- conformance with partial view), only used here to post error
9973 D := First_Discriminant (T);
9974 New_D := First (Discriminant_Specifications (N));
9975 while Present (D) loop
9976 Prev_D := Current_Entity (D);
9977 Set_Current_Entity (D);
9978 Set_Is_Immediately_Visible (D);
9979 Set_Homonym (D, Prev_D);
9981 -- Handle the case where there is an untagged partial view and
9982 -- the full view is tagged: must disallow discriminants with
9983 -- defaults, unless compiling for Ada 2012, which allows a
9984 -- limited tagged type to have defaulted discriminants (see
9985 -- AI05-0214). However, suppress the error here if it was
9986 -- already reported on the default expression of the partial
9989 if Is_Tagged_Type (T)
9990 and then Present (Expression (Parent (D)))
9991 and then (not Is_Limited_Type (Current_Scope)
9992 or else Ada_Version < Ada_2012)
9993 and then not Error_Posted (Expression (Parent (D)))
9995 if Ada_Version >= Ada_2012 then
9997 ("discriminants of nonlimited tagged type cannot have"
9999 Expression (New_D));
10002 ("discriminants of tagged type cannot have defaults",
10003 Expression (New_D));
10007 -- Ada 2005 (AI-230): Access discriminant allowed in
10008 -- non-limited record types.
10010 if Ada_Version < Ada_2005 then
10012 -- This restriction gets applied to the full type here. It
10013 -- has already been applied earlier to the partial view.
10015 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
10018 Next_Discriminant (D);
10023 elsif Present (Discriminant_Specifications (N)) then
10024 Process_Discriminants (N, Prev);
10026 end Check_Or_Process_Discriminants;
10028 ----------------------
10029 -- Check_Real_Bound --
10030 ----------------------
10032 procedure Check_Real_Bound (Bound : Node_Id) is
10034 if not Is_Real_Type (Etype (Bound)) then
10036 ("bound in real type definition must be of real type", Bound);
10038 elsif not Is_OK_Static_Expression (Bound) then
10039 Flag_Non_Static_Expr
10040 ("non-static expression used for real type bound!", Bound);
10047 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
10049 Resolve (Bound, Standard_Float);
10050 end Check_Real_Bound;
10052 ------------------------------
10053 -- Complete_Private_Subtype --
10054 ------------------------------
10056 procedure Complete_Private_Subtype
10059 Full_Base : Entity_Id;
10060 Related_Nod : Node_Id)
10062 Save_Next_Entity : Entity_Id;
10063 Save_Homonym : Entity_Id;
10066 -- Set semantic attributes for (implicit) private subtype completion.
10067 -- If the full type has no discriminants, then it is a copy of the full
10068 -- view of the base. Otherwise, it is a subtype of the base with a
10069 -- possible discriminant constraint. Save and restore the original
10070 -- Next_Entity field of full to ensure that the calls to Copy_Node
10071 -- do not corrupt the entity chain.
10073 -- Note that the type of the full view is the same entity as the type of
10074 -- the partial view. In this fashion, the subtype has access to the
10075 -- correct view of the parent.
10077 Save_Next_Entity := Next_Entity (Full);
10078 Save_Homonym := Homonym (Priv);
10080 case Ekind (Full_Base) is
10081 when E_Record_Type |
10087 Copy_Node (Priv, Full);
10089 Set_Has_Discriminants (Full, Has_Discriminants (Full_Base));
10090 Set_First_Entity (Full, First_Entity (Full_Base));
10091 Set_Last_Entity (Full, Last_Entity (Full_Base));
10094 Copy_Node (Full_Base, Full);
10095 Set_Chars (Full, Chars (Priv));
10096 Conditional_Delay (Full, Priv);
10097 Set_Sloc (Full, Sloc (Priv));
10100 Set_Next_Entity (Full, Save_Next_Entity);
10101 Set_Homonym (Full, Save_Homonym);
10102 Set_Associated_Node_For_Itype (Full, Related_Nod);
10104 -- Set common attributes for all subtypes: kind, convention, etc.
10106 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
10107 Set_Convention (Full, Convention (Full_Base));
10109 -- The Etype of the full view is inconsistent. Gigi needs to see the
10110 -- structural full view, which is what the current scheme gives:
10111 -- the Etype of the full view is the etype of the full base. However,
10112 -- if the full base is a derived type, the full view then looks like
10113 -- a subtype of the parent, not a subtype of the full base. If instead
10116 -- Set_Etype (Full, Full_Base);
10118 -- then we get inconsistencies in the front-end (confusion between
10119 -- views). Several outstanding bugs are related to this ???
10121 Set_Is_First_Subtype (Full, False);
10122 Set_Scope (Full, Scope (Priv));
10123 Set_Size_Info (Full, Full_Base);
10124 Set_RM_Size (Full, RM_Size (Full_Base));
10125 Set_Is_Itype (Full);
10127 -- A subtype of a private-type-without-discriminants, whose full-view
10128 -- has discriminants with default expressions, is not constrained!
10130 if not Has_Discriminants (Priv) then
10131 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
10133 if Has_Discriminants (Full_Base) then
10134 Set_Discriminant_Constraint
10135 (Full, Discriminant_Constraint (Full_Base));
10137 -- The partial view may have been indefinite, the full view
10140 Set_Has_Unknown_Discriminants
10141 (Full, Has_Unknown_Discriminants (Full_Base));
10145 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
10146 Set_Depends_On_Private (Full, Has_Private_Component (Full));
10148 -- Freeze the private subtype entity if its parent is delayed, and not
10149 -- already frozen. We skip this processing if the type is an anonymous
10150 -- subtype of a record component, or is the corresponding record of a
10151 -- protected type, since ???
10153 if not Is_Type (Scope (Full)) then
10154 Set_Has_Delayed_Freeze (Full,
10155 Has_Delayed_Freeze (Full_Base)
10156 and then (not Is_Frozen (Full_Base)));
10159 Set_Freeze_Node (Full, Empty);
10160 Set_Is_Frozen (Full, False);
10161 Set_Full_View (Priv, Full);
10163 if Has_Discriminants (Full) then
10164 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
10165 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
10167 if Has_Unknown_Discriminants (Full) then
10168 Set_Discriminant_Constraint (Full, No_Elist);
10172 if Ekind (Full_Base) = E_Record_Type
10173 and then Has_Discriminants (Full_Base)
10174 and then Has_Discriminants (Priv) -- might not, if errors
10175 and then not Has_Unknown_Discriminants (Priv)
10176 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
10178 Create_Constrained_Components
10179 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
10181 -- If the full base is itself derived from private, build a congruent
10182 -- subtype of its underlying type, for use by the back end. For a
10183 -- constrained record component, the declaration cannot be placed on
10184 -- the component list, but it must nevertheless be built an analyzed, to
10185 -- supply enough information for Gigi to compute the size of component.
10187 elsif Ekind (Full_Base) in Private_Kind
10188 and then Is_Derived_Type (Full_Base)
10189 and then Has_Discriminants (Full_Base)
10190 and then (Ekind (Current_Scope) /= E_Record_Subtype)
10192 if not Is_Itype (Priv)
10194 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
10196 Build_Underlying_Full_View
10197 (Parent (Priv), Full, Etype (Full_Base));
10199 elsif Nkind (Related_Nod) = N_Component_Declaration then
10200 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
10203 elsif Is_Record_Type (Full_Base) then
10205 -- Show Full is simply a renaming of Full_Base
10207 Set_Cloned_Subtype (Full, Full_Base);
10210 -- It is unsafe to share to bounds of a scalar type, because the Itype
10211 -- is elaborated on demand, and if a bound is non-static then different
10212 -- orders of elaboration in different units will lead to different
10213 -- external symbols.
10215 if Is_Scalar_Type (Full_Base) then
10216 Set_Scalar_Range (Full,
10217 Make_Range (Sloc (Related_Nod),
10219 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
10221 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
10223 -- This completion inherits the bounds of the full parent, but if
10224 -- the parent is an unconstrained floating point type, so is the
10227 if Is_Floating_Point_Type (Full_Base) then
10228 Set_Includes_Infinities
10229 (Scalar_Range (Full), Has_Infinities (Full_Base));
10233 -- ??? It seems that a lot of fields are missing that should be copied
10234 -- from Full_Base to Full. Here are some that are introduced in a
10235 -- non-disruptive way but a cleanup is necessary.
10237 if Is_Tagged_Type (Full_Base) then
10238 Set_Is_Tagged_Type (Full);
10239 Set_Direct_Primitive_Operations (Full,
10240 Direct_Primitive_Operations (Full_Base));
10242 -- Inherit class_wide type of full_base in case the partial view was
10243 -- not tagged. Otherwise it has already been created when the private
10244 -- subtype was analyzed.
10246 if No (Class_Wide_Type (Full)) then
10247 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
10250 -- If this is a subtype of a protected or task type, constrain its
10251 -- corresponding record, unless this is a subtype without constraints,
10252 -- i.e. a simple renaming as with an actual subtype in an instance.
10254 elsif Is_Concurrent_Type (Full_Base) then
10255 if Has_Discriminants (Full)
10256 and then Present (Corresponding_Record_Type (Full_Base))
10258 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
10260 Set_Corresponding_Record_Type (Full,
10261 Constrain_Corresponding_Record
10262 (Full, Corresponding_Record_Type (Full_Base),
10263 Related_Nod, Full_Base));
10266 Set_Corresponding_Record_Type (Full,
10267 Corresponding_Record_Type (Full_Base));
10271 -- Link rep item chain, and also setting of Has_Predicates from private
10272 -- subtype to full subtype, since we will need these on the full subtype
10273 -- to create the predicate function. Note that the full subtype may
10274 -- already have rep items, inherited from the full view of the base
10275 -- type, so we must be sure not to overwrite these entries.
10279 Next_Item : Node_Id;
10282 Item := First_Rep_Item (Full);
10284 -- If no existing rep items on full type, we can just link directly
10285 -- to the list of items on the private type.
10288 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
10290 -- Otherwise, search to the end of items currently linked to the full
10291 -- subtype and append the private items to the end. However, if Priv
10292 -- and Full already have the same list of rep items, then the append
10293 -- is not done, as that would create a circularity.
10295 elsif Item /= First_Rep_Item (Priv) then
10297 Next_Item := Next_Rep_Item (Item);
10298 exit when No (Next_Item);
10302 -- And link the private type items at the end of the chain
10304 Set_Next_Rep_Item (Item, First_Rep_Item (Priv));
10308 -- Make sure Has_Predicates is set on full type if it is set on the
10309 -- private type. Note that it may already be set on the full type and
10310 -- if so, we don't want to unset it.
10312 if Has_Predicates (Priv) then
10313 Set_Has_Predicates (Full);
10315 end Complete_Private_Subtype;
10317 ----------------------------
10318 -- Constant_Redeclaration --
10319 ----------------------------
10321 procedure Constant_Redeclaration
10326 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
10327 Obj_Def : constant Node_Id := Object_Definition (N);
10330 procedure Check_Possible_Deferred_Completion
10331 (Prev_Id : Entity_Id;
10332 Prev_Obj_Def : Node_Id;
10333 Curr_Obj_Def : Node_Id);
10334 -- Determine whether the two object definitions describe the partial
10335 -- and the full view of a constrained deferred constant. Generate
10336 -- a subtype for the full view and verify that it statically matches
10337 -- the subtype of the partial view.
10339 procedure Check_Recursive_Declaration (Typ : Entity_Id);
10340 -- If deferred constant is an access type initialized with an allocator,
10341 -- check whether there is an illegal recursion in the definition,
10342 -- through a default value of some record subcomponent. This is normally
10343 -- detected when generating init procs, but requires this additional
10344 -- mechanism when expansion is disabled.
10346 ----------------------------------------
10347 -- Check_Possible_Deferred_Completion --
10348 ----------------------------------------
10350 procedure Check_Possible_Deferred_Completion
10351 (Prev_Id : Entity_Id;
10352 Prev_Obj_Def : Node_Id;
10353 Curr_Obj_Def : Node_Id)
10356 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
10357 and then Present (Constraint (Prev_Obj_Def))
10358 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
10359 and then Present (Constraint (Curr_Obj_Def))
10362 Loc : constant Source_Ptr := Sloc (N);
10363 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'S');
10364 Decl : constant Node_Id :=
10365 Make_Subtype_Declaration (Loc,
10366 Defining_Identifier => Def_Id,
10367 Subtype_Indication =>
10368 Relocate_Node (Curr_Obj_Def));
10371 Insert_Before_And_Analyze (N, Decl);
10372 Set_Etype (Id, Def_Id);
10374 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
10375 Error_Msg_Sloc := Sloc (Prev_Id);
10376 Error_Msg_N ("subtype does not statically match deferred " &
10377 "declaration#", N);
10381 end Check_Possible_Deferred_Completion;
10383 ---------------------------------
10384 -- Check_Recursive_Declaration --
10385 ---------------------------------
10387 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
10391 if Is_Record_Type (Typ) then
10392 Comp := First_Component (Typ);
10393 while Present (Comp) loop
10394 if Comes_From_Source (Comp) then
10395 if Present (Expression (Parent (Comp)))
10396 and then Is_Entity_Name (Expression (Parent (Comp)))
10397 and then Entity (Expression (Parent (Comp))) = Prev
10399 Error_Msg_Sloc := Sloc (Parent (Comp));
10401 ("illegal circularity with declaration for&#",
10405 elsif Is_Record_Type (Etype (Comp)) then
10406 Check_Recursive_Declaration (Etype (Comp));
10410 Next_Component (Comp);
10413 end Check_Recursive_Declaration;
10415 -- Start of processing for Constant_Redeclaration
10418 if Nkind (Parent (Prev)) = N_Object_Declaration then
10419 if Nkind (Object_Definition
10420 (Parent (Prev))) = N_Subtype_Indication
10422 -- Find type of new declaration. The constraints of the two
10423 -- views must match statically, but there is no point in
10424 -- creating an itype for the full view.
10426 if Nkind (Obj_Def) = N_Subtype_Indication then
10427 Find_Type (Subtype_Mark (Obj_Def));
10428 New_T := Entity (Subtype_Mark (Obj_Def));
10431 Find_Type (Obj_Def);
10432 New_T := Entity (Obj_Def);
10438 -- The full view may impose a constraint, even if the partial
10439 -- view does not, so construct the subtype.
10441 New_T := Find_Type_Of_Object (Obj_Def, N);
10446 -- Current declaration is illegal, diagnosed below in Enter_Name
10452 -- If previous full declaration or a renaming declaration exists, or if
10453 -- a homograph is present, let Enter_Name handle it, either with an
10454 -- error or with the removal of an overridden implicit subprogram.
10456 if Ekind (Prev) /= E_Constant
10457 or else Nkind (Parent (Prev)) = N_Object_Renaming_Declaration
10458 or else Present (Expression (Parent (Prev)))
10459 or else Present (Full_View (Prev))
10463 -- Verify that types of both declarations match, or else that both types
10464 -- are anonymous access types whose designated subtypes statically match
10465 -- (as allowed in Ada 2005 by AI-385).
10467 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
10469 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
10470 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
10471 or else Is_Access_Constant (Etype (New_T)) /=
10472 Is_Access_Constant (Etype (Prev))
10473 or else Can_Never_Be_Null (Etype (New_T)) /=
10474 Can_Never_Be_Null (Etype (Prev))
10475 or else Null_Exclusion_Present (Parent (Prev)) /=
10476 Null_Exclusion_Present (Parent (Id))
10477 or else not Subtypes_Statically_Match
10478 (Designated_Type (Etype (Prev)),
10479 Designated_Type (Etype (New_T))))
10481 Error_Msg_Sloc := Sloc (Prev);
10482 Error_Msg_N ("type does not match declaration#", N);
10483 Set_Full_View (Prev, Id);
10484 Set_Etype (Id, Any_Type);
10487 Null_Exclusion_Present (Parent (Prev))
10488 and then not Null_Exclusion_Present (N)
10490 Error_Msg_Sloc := Sloc (Prev);
10491 Error_Msg_N ("null-exclusion does not match declaration#", N);
10492 Set_Full_View (Prev, Id);
10493 Set_Etype (Id, Any_Type);
10495 -- If so, process the full constant declaration
10498 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
10499 -- the deferred declaration is constrained, then the subtype defined
10500 -- by the subtype_indication in the full declaration shall match it
10503 Check_Possible_Deferred_Completion
10505 Prev_Obj_Def => Object_Definition (Parent (Prev)),
10506 Curr_Obj_Def => Obj_Def);
10508 Set_Full_View (Prev, Id);
10509 Set_Is_Public (Id, Is_Public (Prev));
10510 Set_Is_Internal (Id);
10511 Append_Entity (Id, Current_Scope);
10513 -- Check ALIASED present if present before (RM 7.4(7))
10515 if Is_Aliased (Prev)
10516 and then not Aliased_Present (N)
10518 Error_Msg_Sloc := Sloc (Prev);
10519 Error_Msg_N ("ALIASED required (see declaration#)", N);
10522 -- Check that placement is in private part and that the incomplete
10523 -- declaration appeared in the visible part.
10525 if Ekind (Current_Scope) = E_Package
10526 and then not In_Private_Part (Current_Scope)
10528 Error_Msg_Sloc := Sloc (Prev);
10530 ("full constant for declaration#"
10531 & " must be in private part", N);
10533 elsif Ekind (Current_Scope) = E_Package
10535 List_Containing (Parent (Prev)) /=
10536 Visible_Declarations
10537 (Specification (Unit_Declaration_Node (Current_Scope)))
10540 ("deferred constant must be declared in visible part",
10544 if Is_Access_Type (T)
10545 and then Nkind (Expression (N)) = N_Allocator
10547 Check_Recursive_Declaration (Designated_Type (T));
10550 end Constant_Redeclaration;
10552 ----------------------
10553 -- Constrain_Access --
10554 ----------------------
10556 procedure Constrain_Access
10557 (Def_Id : in out Entity_Id;
10559 Related_Nod : Node_Id)
10561 T : constant Entity_Id := Entity (Subtype_Mark (S));
10562 Desig_Type : constant Entity_Id := Designated_Type (T);
10563 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
10564 Constraint_OK : Boolean := True;
10566 function Has_Defaulted_Discriminants (Typ : Entity_Id) return Boolean;
10567 -- Simple predicate to test for defaulted discriminants
10568 -- Shouldn't this be in sem_util???
10570 ---------------------------------
10571 -- Has_Defaulted_Discriminants --
10572 ---------------------------------
10574 function Has_Defaulted_Discriminants (Typ : Entity_Id) return Boolean is
10576 return Has_Discriminants (Typ)
10577 and then Present (First_Discriminant (Typ))
10579 (Discriminant_Default_Value (First_Discriminant (Typ)));
10580 end Has_Defaulted_Discriminants;
10582 -- Start of processing for Constrain_Access
10585 if Is_Array_Type (Desig_Type) then
10586 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
10588 elsif (Is_Record_Type (Desig_Type)
10589 or else Is_Incomplete_Or_Private_Type (Desig_Type))
10590 and then not Is_Constrained (Desig_Type)
10592 -- ??? The following code is a temporary kludge to ignore a
10593 -- discriminant constraint on access type if it is constraining
10594 -- the current record. Avoid creating the implicit subtype of the
10595 -- record we are currently compiling since right now, we cannot
10596 -- handle these. For now, just return the access type itself.
10598 if Desig_Type = Current_Scope
10599 and then No (Def_Id)
10601 Set_Ekind (Desig_Subtype, E_Record_Subtype);
10602 Def_Id := Entity (Subtype_Mark (S));
10604 -- This call added to ensure that the constraint is analyzed
10605 -- (needed for a B test). Note that we still return early from
10606 -- this procedure to avoid recursive processing. ???
10608 Constrain_Discriminated_Type
10609 (Desig_Subtype, S, Related_Nod, For_Access => True);
10613 if (Ekind (T) = E_General_Access_Type
10614 or else Ada_Version >= Ada_2005)
10615 and then Has_Private_Declaration (Desig_Type)
10616 and then In_Open_Scopes (Scope (Desig_Type))
10617 and then Has_Discriminants (Desig_Type)
10619 -- Enforce rule that the constraint is illegal if there is
10620 -- an unconstrained view of the designated type. This means
10621 -- that the partial view (either a private type declaration or
10622 -- a derivation from a private type) has no discriminants.
10623 -- (Defect Report 8652/0008, Technical Corrigendum 1, checked
10624 -- by ACATS B371001).
10626 -- Rule updated for Ada 2005: the private type is said to have
10627 -- a constrained partial view, given that objects of the type
10628 -- can be declared. Furthermore, the rule applies to all access
10629 -- types, unlike the rule concerning default discriminants.
10632 Pack : constant Node_Id :=
10633 Unit_Declaration_Node (Scope (Desig_Type));
10638 if Nkind (Pack) = N_Package_Declaration then
10639 Decls := Visible_Declarations (Specification (Pack));
10640 Decl := First (Decls);
10641 while Present (Decl) loop
10642 if (Nkind (Decl) = N_Private_Type_Declaration
10644 Chars (Defining_Identifier (Decl)) =
10645 Chars (Desig_Type))
10648 (Nkind (Decl) = N_Full_Type_Declaration
10650 Chars (Defining_Identifier (Decl)) =
10652 and then Is_Derived_Type (Desig_Type)
10654 Has_Private_Declaration (Etype (Desig_Type)))
10656 if No (Discriminant_Specifications (Decl)) then
10658 ("cannot constrain general access type if " &
10659 "designated type has constrained partial view",
10672 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
10673 For_Access => True);
10675 elsif (Is_Task_Type (Desig_Type)
10676 or else Is_Protected_Type (Desig_Type))
10677 and then not Is_Constrained (Desig_Type)
10679 Constrain_Concurrent
10680 (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
10683 Error_Msg_N ("invalid constraint on access type", S);
10684 Desig_Subtype := Desig_Type; -- Ignore invalid constraint.
10685 Constraint_OK := False;
10688 if No (Def_Id) then
10689 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
10691 Set_Ekind (Def_Id, E_Access_Subtype);
10694 if Constraint_OK then
10695 Set_Etype (Def_Id, Base_Type (T));
10697 if Is_Private_Type (Desig_Type) then
10698 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
10701 Set_Etype (Def_Id, Any_Type);
10704 Set_Size_Info (Def_Id, T);
10705 Set_Is_Constrained (Def_Id, Constraint_OK);
10706 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
10707 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
10708 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
10710 Conditional_Delay (Def_Id, T);
10712 -- AI-363 : Subtypes of general access types whose designated types have
10713 -- default discriminants are disallowed. In instances, the rule has to
10714 -- be checked against the actual, of which T is the subtype. In a
10715 -- generic body, the rule is checked assuming that the actual type has
10716 -- defaulted discriminants.
10718 if Ada_Version >= Ada_2005 or else Warn_On_Ada_2005_Compatibility then
10719 if Ekind (Base_Type (T)) = E_General_Access_Type
10720 and then Has_Defaulted_Discriminants (Desig_Type)
10722 if Ada_Version < Ada_2005 then
10724 ("access subtype of general access type would not " &
10725 "be allowed in Ada 2005?", S);
10728 ("access subtype of general access type not allowed", S);
10731 Error_Msg_N ("\discriminants have defaults", S);
10733 elsif Is_Access_Type (T)
10734 and then Is_Generic_Type (Desig_Type)
10735 and then Has_Discriminants (Desig_Type)
10736 and then In_Package_Body (Current_Scope)
10738 if Ada_Version < Ada_2005 then
10740 ("access subtype would not be allowed in generic body " &
10741 "in Ada 2005?", S);
10744 ("access subtype not allowed in generic body", S);
10748 ("\designated type is a discriminated formal", S);
10751 end Constrain_Access;
10753 ---------------------
10754 -- Constrain_Array --
10755 ---------------------
10757 procedure Constrain_Array
10758 (Def_Id : in out Entity_Id;
10760 Related_Nod : Node_Id;
10761 Related_Id : Entity_Id;
10762 Suffix : Character)
10764 C : constant Node_Id := Constraint (SI);
10765 Number_Of_Constraints : Nat := 0;
10768 Constraint_OK : Boolean := True;
10771 T := Entity (Subtype_Mark (SI));
10773 if Ekind (T) in Access_Kind then
10774 T := Designated_Type (T);
10777 -- If an index constraint follows a subtype mark in a subtype indication
10778 -- then the type or subtype denoted by the subtype mark must not already
10779 -- impose an index constraint. The subtype mark must denote either an
10780 -- unconstrained array type or an access type whose designated type
10781 -- is such an array type... (RM 3.6.1)
10783 if Is_Constrained (T) then
10784 Error_Msg_N ("array type is already constrained", Subtype_Mark (SI));
10785 Constraint_OK := False;
10788 S := First (Constraints (C));
10789 while Present (S) loop
10790 Number_Of_Constraints := Number_Of_Constraints + 1;
10794 -- In either case, the index constraint must provide a discrete
10795 -- range for each index of the array type and the type of each
10796 -- discrete range must be the same as that of the corresponding
10797 -- index. (RM 3.6.1)
10799 if Number_Of_Constraints /= Number_Dimensions (T) then
10800 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
10801 Constraint_OK := False;
10804 S := First (Constraints (C));
10805 Index := First_Index (T);
10808 -- Apply constraints to each index type
10810 for J in 1 .. Number_Of_Constraints loop
10811 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
10819 if No (Def_Id) then
10821 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
10822 Set_Parent (Def_Id, Related_Nod);
10825 Set_Ekind (Def_Id, E_Array_Subtype);
10828 Set_Size_Info (Def_Id, (T));
10829 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
10830 Set_Etype (Def_Id, Base_Type (T));
10832 if Constraint_OK then
10833 Set_First_Index (Def_Id, First (Constraints (C)));
10835 Set_First_Index (Def_Id, First_Index (T));
10838 Set_Is_Constrained (Def_Id, True);
10839 Set_Is_Aliased (Def_Id, Is_Aliased (T));
10840 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
10842 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
10843 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
10845 -- A subtype does not inherit the packed_array_type of is parent. We
10846 -- need to initialize the attribute because if Def_Id is previously
10847 -- analyzed through a limited_with clause, it will have the attributes
10848 -- of an incomplete type, one of which is an Elist that overlaps the
10849 -- Packed_Array_Type field.
10851 Set_Packed_Array_Type (Def_Id, Empty);
10853 -- Build a freeze node if parent still needs one. Also make sure that
10854 -- the Depends_On_Private status is set because the subtype will need
10855 -- reprocessing at the time the base type does, and also we must set a
10856 -- conditional delay.
10858 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
10859 Conditional_Delay (Def_Id, T);
10860 end Constrain_Array;
10862 ------------------------------
10863 -- Constrain_Component_Type --
10864 ------------------------------
10866 function Constrain_Component_Type
10868 Constrained_Typ : Entity_Id;
10869 Related_Node : Node_Id;
10871 Constraints : Elist_Id) return Entity_Id
10873 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
10874 Compon_Type : constant Entity_Id := Etype (Comp);
10876 function Build_Constrained_Array_Type
10877 (Old_Type : Entity_Id) return Entity_Id;
10878 -- If Old_Type is an array type, one of whose indexes is constrained
10879 -- by a discriminant, build an Itype whose constraint replaces the
10880 -- discriminant with its value in the constraint.
10882 function Build_Constrained_Discriminated_Type
10883 (Old_Type : Entity_Id) return Entity_Id;
10884 -- Ditto for record components
10886 function Build_Constrained_Access_Type
10887 (Old_Type : Entity_Id) return Entity_Id;
10888 -- Ditto for access types. Makes use of previous two functions, to
10889 -- constrain designated type.
10891 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
10892 -- T is an array or discriminated type, C is a list of constraints
10893 -- that apply to T. This routine builds the constrained subtype.
10895 function Is_Discriminant (Expr : Node_Id) return Boolean;
10896 -- Returns True if Expr is a discriminant
10898 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
10899 -- Find the value of discriminant Discrim in Constraint
10901 -----------------------------------
10902 -- Build_Constrained_Access_Type --
10903 -----------------------------------
10905 function Build_Constrained_Access_Type
10906 (Old_Type : Entity_Id) return Entity_Id
10908 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
10910 Desig_Subtype : Entity_Id;
10914 -- if the original access type was not embedded in the enclosing
10915 -- type definition, there is no need to produce a new access
10916 -- subtype. In fact every access type with an explicit constraint
10917 -- generates an itype whose scope is the enclosing record.
10919 if not Is_Type (Scope (Old_Type)) then
10922 elsif Is_Array_Type (Desig_Type) then
10923 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
10925 elsif Has_Discriminants (Desig_Type) then
10927 -- This may be an access type to an enclosing record type for
10928 -- which we are constructing the constrained components. Return
10929 -- the enclosing record subtype. This is not always correct,
10930 -- but avoids infinite recursion. ???
10932 Desig_Subtype := Any_Type;
10934 for J in reverse 0 .. Scope_Stack.Last loop
10935 Scop := Scope_Stack.Table (J).Entity;
10938 and then Base_Type (Scop) = Base_Type (Desig_Type)
10940 Desig_Subtype := Scop;
10943 exit when not Is_Type (Scop);
10946 if Desig_Subtype = Any_Type then
10948 Build_Constrained_Discriminated_Type (Desig_Type);
10955 if Desig_Subtype /= Desig_Type then
10957 -- The Related_Node better be here or else we won't be able
10958 -- to attach new itypes to a node in the tree.
10960 pragma Assert (Present (Related_Node));
10962 Itype := Create_Itype (E_Access_Subtype, Related_Node);
10964 Set_Etype (Itype, Base_Type (Old_Type));
10965 Set_Size_Info (Itype, (Old_Type));
10966 Set_Directly_Designated_Type (Itype, Desig_Subtype);
10967 Set_Depends_On_Private (Itype, Has_Private_Component
10969 Set_Is_Access_Constant (Itype, Is_Access_Constant
10972 -- The new itype needs freezing when it depends on a not frozen
10973 -- type and the enclosing subtype needs freezing.
10975 if Has_Delayed_Freeze (Constrained_Typ)
10976 and then not Is_Frozen (Constrained_Typ)
10978 Conditional_Delay (Itype, Base_Type (Old_Type));
10986 end Build_Constrained_Access_Type;
10988 ----------------------------------
10989 -- Build_Constrained_Array_Type --
10990 ----------------------------------
10992 function Build_Constrained_Array_Type
10993 (Old_Type : Entity_Id) return Entity_Id
10997 Old_Index : Node_Id;
10998 Range_Node : Node_Id;
10999 Constr_List : List_Id;
11001 Need_To_Create_Itype : Boolean := False;
11004 Old_Index := First_Index (Old_Type);
11005 while Present (Old_Index) loop
11006 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
11008 if Is_Discriminant (Lo_Expr)
11009 or else Is_Discriminant (Hi_Expr)
11011 Need_To_Create_Itype := True;
11014 Next_Index (Old_Index);
11017 if Need_To_Create_Itype then
11018 Constr_List := New_List;
11020 Old_Index := First_Index (Old_Type);
11021 while Present (Old_Index) loop
11022 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
11024 if Is_Discriminant (Lo_Expr) then
11025 Lo_Expr := Get_Discr_Value (Lo_Expr);
11028 if Is_Discriminant (Hi_Expr) then
11029 Hi_Expr := Get_Discr_Value (Hi_Expr);
11034 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
11036 Append (Range_Node, To => Constr_List);
11038 Next_Index (Old_Index);
11041 return Build_Subtype (Old_Type, Constr_List);
11046 end Build_Constrained_Array_Type;
11048 ------------------------------------------
11049 -- Build_Constrained_Discriminated_Type --
11050 ------------------------------------------
11052 function Build_Constrained_Discriminated_Type
11053 (Old_Type : Entity_Id) return Entity_Id
11056 Constr_List : List_Id;
11057 Old_Constraint : Elmt_Id;
11059 Need_To_Create_Itype : Boolean := False;
11062 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
11063 while Present (Old_Constraint) loop
11064 Expr := Node (Old_Constraint);
11066 if Is_Discriminant (Expr) then
11067 Need_To_Create_Itype := True;
11070 Next_Elmt (Old_Constraint);
11073 if Need_To_Create_Itype then
11074 Constr_List := New_List;
11076 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
11077 while Present (Old_Constraint) loop
11078 Expr := Node (Old_Constraint);
11080 if Is_Discriminant (Expr) then
11081 Expr := Get_Discr_Value (Expr);
11084 Append (New_Copy_Tree (Expr), To => Constr_List);
11086 Next_Elmt (Old_Constraint);
11089 return Build_Subtype (Old_Type, Constr_List);
11094 end Build_Constrained_Discriminated_Type;
11096 -------------------
11097 -- Build_Subtype --
11098 -------------------
11100 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
11102 Subtyp_Decl : Node_Id;
11103 Def_Id : Entity_Id;
11104 Btyp : Entity_Id := Base_Type (T);
11107 -- The Related_Node better be here or else we won't be able to
11108 -- attach new itypes to a node in the tree.
11110 pragma Assert (Present (Related_Node));
11112 -- If the view of the component's type is incomplete or private
11113 -- with unknown discriminants, then the constraint must be applied
11114 -- to the full type.
11116 if Has_Unknown_Discriminants (Btyp)
11117 and then Present (Underlying_Type (Btyp))
11119 Btyp := Underlying_Type (Btyp);
11123 Make_Subtype_Indication (Loc,
11124 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
11125 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
11127 Def_Id := Create_Itype (Ekind (T), Related_Node);
11130 Make_Subtype_Declaration (Loc,
11131 Defining_Identifier => Def_Id,
11132 Subtype_Indication => Indic);
11134 Set_Parent (Subtyp_Decl, Parent (Related_Node));
11136 -- Itypes must be analyzed with checks off (see package Itypes)
11138 Analyze (Subtyp_Decl, Suppress => All_Checks);
11143 ---------------------
11144 -- Get_Discr_Value --
11145 ---------------------
11147 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
11152 -- The discriminant may be declared for the type, in which case we
11153 -- find it by iterating over the list of discriminants. If the
11154 -- discriminant is inherited from a parent type, it appears as the
11155 -- corresponding discriminant of the current type. This will be the
11156 -- case when constraining an inherited component whose constraint is
11157 -- given by a discriminant of the parent.
11159 D := First_Discriminant (Typ);
11160 E := First_Elmt (Constraints);
11162 while Present (D) loop
11163 if D = Entity (Discrim)
11164 or else D = CR_Discriminant (Entity (Discrim))
11165 or else Corresponding_Discriminant (D) = Entity (Discrim)
11170 Next_Discriminant (D);
11174 -- The Corresponding_Discriminant mechanism is incomplete, because
11175 -- the correspondence between new and old discriminants is not one
11176 -- to one: one new discriminant can constrain several old ones. In
11177 -- that case, scan sequentially the stored_constraint, the list of
11178 -- discriminants of the parents, and the constraints.
11179 -- Previous code checked for the present of the Stored_Constraint
11180 -- list for the derived type, but did not use it at all. Should it
11181 -- be present when the component is a discriminated task type?
11183 if Is_Derived_Type (Typ)
11184 and then Scope (Entity (Discrim)) = Etype (Typ)
11186 D := First_Discriminant (Etype (Typ));
11187 E := First_Elmt (Constraints);
11188 while Present (D) loop
11189 if D = Entity (Discrim) then
11193 Next_Discriminant (D);
11198 -- Something is wrong if we did not find the value
11200 raise Program_Error;
11201 end Get_Discr_Value;
11203 ---------------------
11204 -- Is_Discriminant --
11205 ---------------------
11207 function Is_Discriminant (Expr : Node_Id) return Boolean is
11208 Discrim_Scope : Entity_Id;
11211 if Denotes_Discriminant (Expr) then
11212 Discrim_Scope := Scope (Entity (Expr));
11214 -- Either we have a reference to one of Typ's discriminants,
11216 pragma Assert (Discrim_Scope = Typ
11218 -- or to the discriminants of the parent type, in the case
11219 -- of a derivation of a tagged type with variants.
11221 or else Discrim_Scope = Etype (Typ)
11222 or else Full_View (Discrim_Scope) = Etype (Typ)
11224 -- or same as above for the case where the discriminants
11225 -- were declared in Typ's private view.
11227 or else (Is_Private_Type (Discrim_Scope)
11228 and then Chars (Discrim_Scope) = Chars (Typ))
11230 -- or else we are deriving from the full view and the
11231 -- discriminant is declared in the private entity.
11233 or else (Is_Private_Type (Typ)
11234 and then Chars (Discrim_Scope) = Chars (Typ))
11236 -- Or we are constrained the corresponding record of a
11237 -- synchronized type that completes a private declaration.
11239 or else (Is_Concurrent_Record_Type (Typ)
11241 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
11243 -- or we have a class-wide type, in which case make sure the
11244 -- discriminant found belongs to the root type.
11246 or else (Is_Class_Wide_Type (Typ)
11247 and then Etype (Typ) = Discrim_Scope));
11252 -- In all other cases we have something wrong
11255 end Is_Discriminant;
11257 -- Start of processing for Constrain_Component_Type
11260 if Nkind (Parent (Comp)) = N_Component_Declaration
11261 and then Comes_From_Source (Parent (Comp))
11262 and then Comes_From_Source
11263 (Subtype_Indication (Component_Definition (Parent (Comp))))
11266 (Subtype_Indication (Component_Definition (Parent (Comp))))
11268 return Compon_Type;
11270 elsif Is_Array_Type (Compon_Type) then
11271 return Build_Constrained_Array_Type (Compon_Type);
11273 elsif Has_Discriminants (Compon_Type) then
11274 return Build_Constrained_Discriminated_Type (Compon_Type);
11276 elsif Is_Access_Type (Compon_Type) then
11277 return Build_Constrained_Access_Type (Compon_Type);
11280 return Compon_Type;
11282 end Constrain_Component_Type;
11284 --------------------------
11285 -- Constrain_Concurrent --
11286 --------------------------
11288 -- For concurrent types, the associated record value type carries the same
11289 -- discriminants, so when we constrain a concurrent type, we must constrain
11290 -- the corresponding record type as well.
11292 procedure Constrain_Concurrent
11293 (Def_Id : in out Entity_Id;
11295 Related_Nod : Node_Id;
11296 Related_Id : Entity_Id;
11297 Suffix : Character)
11299 T_Ent : Entity_Id := Entity (Subtype_Mark (SI));
11303 if Ekind (T_Ent) in Access_Kind then
11304 T_Ent := Designated_Type (T_Ent);
11307 T_Val := Corresponding_Record_Type (T_Ent);
11309 if Present (T_Val) then
11311 if No (Def_Id) then
11312 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
11315 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
11317 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
11318 Set_Corresponding_Record_Type (Def_Id,
11319 Constrain_Corresponding_Record
11320 (Def_Id, T_Val, Related_Nod, Related_Id));
11323 -- If there is no associated record, expansion is disabled and this
11324 -- is a generic context. Create a subtype in any case, so that
11325 -- semantic analysis can proceed.
11327 if No (Def_Id) then
11328 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
11331 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
11333 end Constrain_Concurrent;
11335 ------------------------------------
11336 -- Constrain_Corresponding_Record --
11337 ------------------------------------
11339 function Constrain_Corresponding_Record
11340 (Prot_Subt : Entity_Id;
11341 Corr_Rec : Entity_Id;
11342 Related_Nod : Node_Id;
11343 Related_Id : Entity_Id) return Entity_Id
11345 T_Sub : constant Entity_Id :=
11346 Create_Itype (E_Record_Subtype, Related_Nod, Related_Id, 'V');
11349 Set_Etype (T_Sub, Corr_Rec);
11350 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
11351 Set_Is_Constrained (T_Sub, True);
11352 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
11353 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
11355 -- As elsewhere, we do not want to create a freeze node for this itype
11356 -- if it is created for a constrained component of an enclosing record
11357 -- because references to outer discriminants will appear out of scope.
11359 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
11360 Conditional_Delay (T_Sub, Corr_Rec);
11362 Set_Is_Frozen (T_Sub);
11365 if Has_Discriminants (Prot_Subt) then -- False only if errors.
11366 Set_Discriminant_Constraint
11367 (T_Sub, Discriminant_Constraint (Prot_Subt));
11368 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
11369 Create_Constrained_Components
11370 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
11373 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
11376 end Constrain_Corresponding_Record;
11378 -----------------------
11379 -- Constrain_Decimal --
11380 -----------------------
11382 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
11383 T : constant Entity_Id := Entity (Subtype_Mark (S));
11384 C : constant Node_Id := Constraint (S);
11385 Loc : constant Source_Ptr := Sloc (C);
11386 Range_Expr : Node_Id;
11387 Digits_Expr : Node_Id;
11392 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
11394 if Nkind (C) = N_Range_Constraint then
11395 Range_Expr := Range_Expression (C);
11396 Digits_Val := Digits_Value (T);
11399 pragma Assert (Nkind (C) = N_Digits_Constraint);
11401 Check_SPARK_Restriction ("digits constraint is not allowed", S);
11403 Digits_Expr := Digits_Expression (C);
11404 Analyze_And_Resolve (Digits_Expr, Any_Integer);
11406 Check_Digits_Expression (Digits_Expr);
11407 Digits_Val := Expr_Value (Digits_Expr);
11409 if Digits_Val > Digits_Value (T) then
11411 ("digits expression is incompatible with subtype", C);
11412 Digits_Val := Digits_Value (T);
11415 if Present (Range_Constraint (C)) then
11416 Range_Expr := Range_Expression (Range_Constraint (C));
11418 Range_Expr := Empty;
11422 Set_Etype (Def_Id, Base_Type (T));
11423 Set_Size_Info (Def_Id, (T));
11424 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11425 Set_Delta_Value (Def_Id, Delta_Value (T));
11426 Set_Scale_Value (Def_Id, Scale_Value (T));
11427 Set_Small_Value (Def_Id, Small_Value (T));
11428 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
11429 Set_Digits_Value (Def_Id, Digits_Val);
11431 -- Manufacture range from given digits value if no range present
11433 if No (Range_Expr) then
11434 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
11438 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
11440 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
11443 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
11444 Set_Discrete_RM_Size (Def_Id);
11446 -- Unconditionally delay the freeze, since we cannot set size
11447 -- information in all cases correctly until the freeze point.
11449 Set_Has_Delayed_Freeze (Def_Id);
11450 end Constrain_Decimal;
11452 ----------------------------------
11453 -- Constrain_Discriminated_Type --
11454 ----------------------------------
11456 procedure Constrain_Discriminated_Type
11457 (Def_Id : Entity_Id;
11459 Related_Nod : Node_Id;
11460 For_Access : Boolean := False)
11462 E : constant Entity_Id := Entity (Subtype_Mark (S));
11465 Elist : Elist_Id := New_Elmt_List;
11467 procedure Fixup_Bad_Constraint;
11468 -- This is called after finding a bad constraint, and after having
11469 -- posted an appropriate error message. The mission is to leave the
11470 -- entity T in as reasonable state as possible!
11472 --------------------------
11473 -- Fixup_Bad_Constraint --
11474 --------------------------
11476 procedure Fixup_Bad_Constraint is
11478 -- Set a reasonable Ekind for the entity. For an incomplete type,
11479 -- we can't do much, but for other types, we can set the proper
11480 -- corresponding subtype kind.
11482 if Ekind (T) = E_Incomplete_Type then
11483 Set_Ekind (Def_Id, Ekind (T));
11485 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
11488 -- Set Etype to the known type, to reduce chances of cascaded errors
11490 Set_Etype (Def_Id, E);
11491 Set_Error_Posted (Def_Id);
11492 end Fixup_Bad_Constraint;
11494 -- Start of processing for Constrain_Discriminated_Type
11497 C := Constraint (S);
11499 -- A discriminant constraint is only allowed in a subtype indication,
11500 -- after a subtype mark. This subtype mark must denote either a type
11501 -- with discriminants, or an access type whose designated type is a
11502 -- type with discriminants. A discriminant constraint specifies the
11503 -- values of these discriminants (RM 3.7.2(5)).
11505 T := Base_Type (Entity (Subtype_Mark (S)));
11507 if Ekind (T) in Access_Kind then
11508 T := Designated_Type (T);
11511 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal.
11512 -- Avoid generating an error for access-to-incomplete subtypes.
11514 if Ada_Version >= Ada_2005
11515 and then Ekind (T) = E_Incomplete_Type
11516 and then Nkind (Parent (S)) = N_Subtype_Declaration
11517 and then not Is_Itype (Def_Id)
11519 -- A little sanity check, emit an error message if the type
11520 -- has discriminants to begin with. Type T may be a regular
11521 -- incomplete type or imported via a limited with clause.
11523 if Has_Discriminants (T)
11525 (From_With_Type (T)
11526 and then Present (Non_Limited_View (T))
11527 and then Nkind (Parent (Non_Limited_View (T))) =
11528 N_Full_Type_Declaration
11529 and then Present (Discriminant_Specifications
11530 (Parent (Non_Limited_View (T)))))
11533 ("(Ada 2005) incomplete subtype may not be constrained", C);
11535 Error_Msg_N ("invalid constraint: type has no discriminant", C);
11538 Fixup_Bad_Constraint;
11541 -- Check that the type has visible discriminants. The type may be
11542 -- a private type with unknown discriminants whose full view has
11543 -- discriminants which are invisible.
11545 elsif not Has_Discriminants (T)
11547 (Has_Unknown_Discriminants (T)
11548 and then Is_Private_Type (T))
11550 Error_Msg_N ("invalid constraint: type has no discriminant", C);
11551 Fixup_Bad_Constraint;
11554 elsif Is_Constrained (E)
11555 or else (Ekind (E) = E_Class_Wide_Subtype
11556 and then Present (Discriminant_Constraint (E)))
11558 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
11559 Fixup_Bad_Constraint;
11563 -- T may be an unconstrained subtype (e.g. a generic actual).
11564 -- Constraint applies to the base type.
11566 T := Base_Type (T);
11568 Elist := Build_Discriminant_Constraints (T, S);
11570 -- If the list returned was empty we had an error in building the
11571 -- discriminant constraint. We have also already signalled an error
11572 -- in the incomplete type case
11574 if Is_Empty_Elmt_List (Elist) then
11575 Fixup_Bad_Constraint;
11579 Build_Discriminated_Subtype (T, Def_Id, Elist, Related_Nod, For_Access);
11580 end Constrain_Discriminated_Type;
11582 ---------------------------
11583 -- Constrain_Enumeration --
11584 ---------------------------
11586 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
11587 T : constant Entity_Id := Entity (Subtype_Mark (S));
11588 C : constant Node_Id := Constraint (S);
11591 -- By default, consider that the enumeration subtype is in ALFA if the
11592 -- entity of its subtype mark is in ALFA. This is reversed later if the
11593 -- range of the subtype is not static.
11595 if Nkind (Original_Node (Parent (Def_Id))) = N_Subtype_Declaration
11596 and then Is_In_ALFA (T)
11598 Set_Is_In_ALFA (Def_Id);
11601 Set_Ekind (Def_Id, E_Enumeration_Subtype);
11603 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
11605 Set_Etype (Def_Id, Base_Type (T));
11606 Set_Size_Info (Def_Id, (T));
11607 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11608 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
11610 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11612 Set_Discrete_RM_Size (Def_Id);
11613 end Constrain_Enumeration;
11615 ----------------------
11616 -- Constrain_Float --
11617 ----------------------
11619 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
11620 T : constant Entity_Id := Entity (Subtype_Mark (S));
11626 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
11628 Set_Etype (Def_Id, Base_Type (T));
11629 Set_Size_Info (Def_Id, (T));
11630 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11632 -- Process the constraint
11634 C := Constraint (S);
11636 -- Digits constraint present
11638 if Nkind (C) = N_Digits_Constraint then
11640 Check_SPARK_Restriction ("digits constraint is not allowed", S);
11641 Check_Restriction (No_Obsolescent_Features, C);
11643 if Warn_On_Obsolescent_Feature then
11645 ("subtype digits constraint is an " &
11646 "obsolescent feature (RM J.3(8))?", C);
11649 D := Digits_Expression (C);
11650 Analyze_And_Resolve (D, Any_Integer);
11651 Check_Digits_Expression (D);
11652 Set_Digits_Value (Def_Id, Expr_Value (D));
11654 -- Check that digits value is in range. Obviously we can do this
11655 -- at compile time, but it is strictly a runtime check, and of
11656 -- course there is an ACVC test that checks this!
11658 if Digits_Value (Def_Id) > Digits_Value (T) then
11659 Error_Msg_Uint_1 := Digits_Value (T);
11660 Error_Msg_N ("?digits value is too large, maximum is ^", D);
11662 Make_Raise_Constraint_Error (Sloc (D),
11663 Reason => CE_Range_Check_Failed);
11664 Insert_Action (Declaration_Node (Def_Id), Rais);
11667 C := Range_Constraint (C);
11669 -- No digits constraint present
11672 Set_Digits_Value (Def_Id, Digits_Value (T));
11675 -- Range constraint present
11677 if Nkind (C) = N_Range_Constraint then
11678 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11680 -- No range constraint present
11683 pragma Assert (No (C));
11684 Set_Scalar_Range (Def_Id, Scalar_Range (T));
11687 Set_Is_Constrained (Def_Id);
11688 end Constrain_Float;
11690 ---------------------
11691 -- Constrain_Index --
11692 ---------------------
11694 procedure Constrain_Index
11697 Related_Nod : Node_Id;
11698 Related_Id : Entity_Id;
11699 Suffix : Character;
11700 Suffix_Index : Nat)
11702 Def_Id : Entity_Id;
11703 R : Node_Id := Empty;
11704 T : constant Entity_Id := Etype (Index);
11707 if Nkind (S) = N_Range
11709 (Nkind (S) = N_Attribute_Reference
11710 and then Attribute_Name (S) = Name_Range)
11712 -- A Range attribute will be transformed into N_Range by Resolve
11718 Process_Range_Expr_In_Decl (R, T, Empty_List);
11720 if not Error_Posted (S)
11722 (Nkind (S) /= N_Range
11723 or else not Covers (T, (Etype (Low_Bound (S))))
11724 or else not Covers (T, (Etype (High_Bound (S)))))
11726 if Base_Type (T) /= Any_Type
11727 and then Etype (Low_Bound (S)) /= Any_Type
11728 and then Etype (High_Bound (S)) /= Any_Type
11730 Error_Msg_N ("range expected", S);
11734 elsif Nkind (S) = N_Subtype_Indication then
11736 -- The parser has verified that this is a discrete indication
11738 Resolve_Discrete_Subtype_Indication (S, T);
11739 R := Range_Expression (Constraint (S));
11741 -- Capture values of bounds and generate temporaries for them if
11742 -- needed, since checks may cause duplication of the expressions
11743 -- which must not be reevaluated.
11745 if Expander_Active then
11746 Force_Evaluation (Low_Bound (R));
11747 Force_Evaluation (High_Bound (R));
11750 elsif Nkind (S) = N_Discriminant_Association then
11752 -- Syntactically valid in subtype indication
11754 Error_Msg_N ("invalid index constraint", S);
11755 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
11758 -- Subtype_Mark case, no anonymous subtypes to construct
11763 if Is_Entity_Name (S) then
11764 if not Is_Type (Entity (S)) then
11765 Error_Msg_N ("expect subtype mark for index constraint", S);
11767 elsif Base_Type (Entity (S)) /= Base_Type (T) then
11768 Wrong_Type (S, Base_Type (T));
11770 -- Check error of subtype with predicate in index constraint
11773 Bad_Predicated_Subtype_Use
11774 ("subtype& has predicate, not allowed in index constraint",
11781 Error_Msg_N ("invalid index constraint", S);
11782 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
11788 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
11790 Set_Etype (Def_Id, Base_Type (T));
11792 if Is_Modular_Integer_Type (T) then
11793 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
11795 elsif Is_Integer_Type (T) then
11796 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
11799 Set_Ekind (Def_Id, E_Enumeration_Subtype);
11800 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
11801 Set_First_Literal (Def_Id, First_Literal (T));
11804 Set_Size_Info (Def_Id, (T));
11805 Set_RM_Size (Def_Id, RM_Size (T));
11806 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11808 Set_Scalar_Range (Def_Id, R);
11810 Set_Etype (S, Def_Id);
11811 Set_Discrete_RM_Size (Def_Id);
11812 end Constrain_Index;
11814 -----------------------
11815 -- Constrain_Integer --
11816 -----------------------
11818 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
11819 T : constant Entity_Id := Entity (Subtype_Mark (S));
11820 C : constant Node_Id := Constraint (S);
11823 -- By default, consider that the integer subtype is in ALFA if the
11824 -- entity of its subtype mark is in ALFA. This is reversed later if the
11825 -- range of the subtype is not static.
11827 if Nkind (Original_Node (Parent (Def_Id))) = N_Subtype_Declaration
11828 and then Is_In_ALFA (T)
11830 Set_Is_In_ALFA (Def_Id);
11833 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11835 if Is_Modular_Integer_Type (T) then
11836 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
11838 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
11841 Set_Etype (Def_Id, Base_Type (T));
11842 Set_Size_Info (Def_Id, (T));
11843 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11844 Set_Discrete_RM_Size (Def_Id);
11845 end Constrain_Integer;
11847 ------------------------------
11848 -- Constrain_Ordinary_Fixed --
11849 ------------------------------
11851 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
11852 T : constant Entity_Id := Entity (Subtype_Mark (S));
11858 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
11859 Set_Etype (Def_Id, Base_Type (T));
11860 Set_Size_Info (Def_Id, (T));
11861 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11862 Set_Small_Value (Def_Id, Small_Value (T));
11864 -- Process the constraint
11866 C := Constraint (S);
11868 -- Delta constraint present
11870 if Nkind (C) = N_Delta_Constraint then
11872 Check_SPARK_Restriction ("delta constraint is not allowed", S);
11873 Check_Restriction (No_Obsolescent_Features, C);
11875 if Warn_On_Obsolescent_Feature then
11877 ("subtype delta constraint is an " &
11878 "obsolescent feature (RM J.3(7))?");
11881 D := Delta_Expression (C);
11882 Analyze_And_Resolve (D, Any_Real);
11883 Check_Delta_Expression (D);
11884 Set_Delta_Value (Def_Id, Expr_Value_R (D));
11886 -- Check that delta value is in range. Obviously we can do this
11887 -- at compile time, but it is strictly a runtime check, and of
11888 -- course there is an ACVC test that checks this!
11890 if Delta_Value (Def_Id) < Delta_Value (T) then
11891 Error_Msg_N ("?delta value is too small", D);
11893 Make_Raise_Constraint_Error (Sloc (D),
11894 Reason => CE_Range_Check_Failed);
11895 Insert_Action (Declaration_Node (Def_Id), Rais);
11898 C := Range_Constraint (C);
11900 -- No delta constraint present
11903 Set_Delta_Value (Def_Id, Delta_Value (T));
11906 -- Range constraint present
11908 if Nkind (C) = N_Range_Constraint then
11909 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11911 -- No range constraint present
11914 pragma Assert (No (C));
11915 Set_Scalar_Range (Def_Id, Scalar_Range (T));
11919 Set_Discrete_RM_Size (Def_Id);
11921 -- Unconditionally delay the freeze, since we cannot set size
11922 -- information in all cases correctly until the freeze point.
11924 Set_Has_Delayed_Freeze (Def_Id);
11925 end Constrain_Ordinary_Fixed;
11927 -----------------------
11928 -- Contain_Interface --
11929 -----------------------
11931 function Contain_Interface
11932 (Iface : Entity_Id;
11933 Ifaces : Elist_Id) return Boolean
11935 Iface_Elmt : Elmt_Id;
11938 if Present (Ifaces) then
11939 Iface_Elmt := First_Elmt (Ifaces);
11940 while Present (Iface_Elmt) loop
11941 if Node (Iface_Elmt) = Iface then
11945 Next_Elmt (Iface_Elmt);
11950 end Contain_Interface;
11952 ---------------------------
11953 -- Convert_Scalar_Bounds --
11954 ---------------------------
11956 procedure Convert_Scalar_Bounds
11958 Parent_Type : Entity_Id;
11959 Derived_Type : Entity_Id;
11962 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
11969 -- Defend against previous errors
11971 if No (Scalar_Range (Derived_Type)) then
11975 Lo := Build_Scalar_Bound
11976 (Type_Low_Bound (Derived_Type),
11977 Parent_Type, Implicit_Base);
11979 Hi := Build_Scalar_Bound
11980 (Type_High_Bound (Derived_Type),
11981 Parent_Type, Implicit_Base);
11988 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
11990 Set_Parent (Rng, N);
11991 Set_Scalar_Range (Derived_Type, Rng);
11993 -- Analyze the bounds
11995 Analyze_And_Resolve (Lo, Implicit_Base);
11996 Analyze_And_Resolve (Hi, Implicit_Base);
11998 -- Analyze the range itself, except that we do not analyze it if
11999 -- the bounds are real literals, and we have a fixed-point type.
12000 -- The reason for this is that we delay setting the bounds in this
12001 -- case till we know the final Small and Size values (see circuit
12002 -- in Freeze.Freeze_Fixed_Point_Type for further details).
12004 if Is_Fixed_Point_Type (Parent_Type)
12005 and then Nkind (Lo) = N_Real_Literal
12006 and then Nkind (Hi) = N_Real_Literal
12010 -- Here we do the analysis of the range
12012 -- Note: we do this manually, since if we do a normal Analyze and
12013 -- Resolve call, there are problems with the conversions used for
12014 -- the derived type range.
12017 Set_Etype (Rng, Implicit_Base);
12018 Set_Analyzed (Rng, True);
12020 end Convert_Scalar_Bounds;
12022 -------------------
12023 -- Copy_And_Swap --
12024 -------------------
12026 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
12028 -- Initialize new full declaration entity by copying the pertinent
12029 -- fields of the corresponding private declaration entity.
12031 -- We temporarily set Ekind to a value appropriate for a type to
12032 -- avoid assert failures in Einfo from checking for setting type
12033 -- attributes on something that is not a type. Ekind (Priv) is an
12034 -- appropriate choice, since it allowed the attributes to be set
12035 -- in the first place. This Ekind value will be modified later.
12037 Set_Ekind (Full, Ekind (Priv));
12039 -- Also set Etype temporarily to Any_Type, again, in the absence
12040 -- of errors, it will be properly reset, and if there are errors,
12041 -- then we want a value of Any_Type to remain.
12043 Set_Etype (Full, Any_Type);
12045 -- Now start copying attributes
12047 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
12049 if Has_Discriminants (Full) then
12050 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
12051 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
12054 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
12055 Set_Homonym (Full, Homonym (Priv));
12056 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
12057 Set_Is_Public (Full, Is_Public (Priv));
12058 Set_Is_Pure (Full, Is_Pure (Priv));
12059 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
12060 Set_Has_Pragma_Unmodified (Full, Has_Pragma_Unmodified (Priv));
12061 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
12062 Set_Has_Pragma_Unreferenced_Objects
12063 (Full, Has_Pragma_Unreferenced_Objects
12066 Conditional_Delay (Full, Priv);
12068 if Is_Tagged_Type (Full) then
12069 Set_Direct_Primitive_Operations (Full,
12070 Direct_Primitive_Operations (Priv));
12072 if Is_Base_Type (Priv) then
12073 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
12077 Set_Is_Volatile (Full, Is_Volatile (Priv));
12078 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
12079 Set_Scope (Full, Scope (Priv));
12080 Set_Next_Entity (Full, Next_Entity (Priv));
12081 Set_First_Entity (Full, First_Entity (Priv));
12082 Set_Last_Entity (Full, Last_Entity (Priv));
12084 -- If access types have been recorded for later handling, keep them in
12085 -- the full view so that they get handled when the full view freeze
12086 -- node is expanded.
12088 if Present (Freeze_Node (Priv))
12089 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
12091 Ensure_Freeze_Node (Full);
12092 Set_Access_Types_To_Process
12093 (Freeze_Node (Full),
12094 Access_Types_To_Process (Freeze_Node (Priv)));
12097 -- Swap the two entities. Now Private is the full type entity and Full
12098 -- is the private one. They will be swapped back at the end of the
12099 -- private part. This swapping ensures that the entity that is visible
12100 -- in the private part is the full declaration.
12102 Exchange_Entities (Priv, Full);
12103 Append_Entity (Full, Scope (Full));
12106 -------------------------------------
12107 -- Copy_Array_Base_Type_Attributes --
12108 -------------------------------------
12110 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
12112 Set_Component_Alignment (T1, Component_Alignment (T2));
12113 Set_Component_Type (T1, Component_Type (T2));
12114 Set_Component_Size (T1, Component_Size (T2));
12115 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
12116 Set_Finalize_Storage_Only (T1, Finalize_Storage_Only (T2));
12117 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
12118 Set_Has_Task (T1, Has_Task (T2));
12119 Set_Is_Packed (T1, Is_Packed (T2));
12120 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
12121 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
12122 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
12123 end Copy_Array_Base_Type_Attributes;
12125 -----------------------------------
12126 -- Copy_Array_Subtype_Attributes --
12127 -----------------------------------
12129 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
12131 Set_Size_Info (T1, T2);
12133 Set_First_Index (T1, First_Index (T2));
12134 Set_Is_Aliased (T1, Is_Aliased (T2));
12135 Set_Is_Atomic (T1, Is_Atomic (T2));
12136 Set_Is_Volatile (T1, Is_Volatile (T2));
12137 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
12138 Set_Is_Constrained (T1, Is_Constrained (T2));
12139 Set_Depends_On_Private (T1, Has_Private_Component (T2));
12140 Set_First_Rep_Item (T1, First_Rep_Item (T2));
12141 Set_Convention (T1, Convention (T2));
12142 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
12143 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
12144 Set_Packed_Array_Type (T1, Packed_Array_Type (T2));
12145 end Copy_Array_Subtype_Attributes;
12147 -----------------------------------
12148 -- Create_Constrained_Components --
12149 -----------------------------------
12151 procedure Create_Constrained_Components
12153 Decl_Node : Node_Id;
12155 Constraints : Elist_Id)
12157 Loc : constant Source_Ptr := Sloc (Subt);
12158 Comp_List : constant Elist_Id := New_Elmt_List;
12159 Parent_Type : constant Entity_Id := Etype (Typ);
12160 Assoc_List : constant List_Id := New_List;
12161 Discr_Val : Elmt_Id;
12165 Is_Static : Boolean := True;
12167 procedure Collect_Fixed_Components (Typ : Entity_Id);
12168 -- Collect parent type components that do not appear in a variant part
12170 procedure Create_All_Components;
12171 -- Iterate over Comp_List to create the components of the subtype
12173 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
12174 -- Creates a new component from Old_Compon, copying all the fields from
12175 -- it, including its Etype, inserts the new component in the Subt entity
12176 -- chain and returns the new component.
12178 function Is_Variant_Record (T : Entity_Id) return Boolean;
12179 -- If true, and discriminants are static, collect only components from
12180 -- variants selected by discriminant values.
12182 ------------------------------
12183 -- Collect_Fixed_Components --
12184 ------------------------------
12186 procedure Collect_Fixed_Components (Typ : Entity_Id) is
12188 -- Build association list for discriminants, and find components of the
12189 -- variant part selected by the values of the discriminants.
12191 Old_C := First_Discriminant (Typ);
12192 Discr_Val := First_Elmt (Constraints);
12193 while Present (Old_C) loop
12194 Append_To (Assoc_List,
12195 Make_Component_Association (Loc,
12196 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
12197 Expression => New_Copy (Node (Discr_Val))));
12199 Next_Elmt (Discr_Val);
12200 Next_Discriminant (Old_C);
12203 -- The tag and the possible parent component are unconditionally in
12206 if Is_Tagged_Type (Typ)
12207 or else Has_Controlled_Component (Typ)
12209 Old_C := First_Component (Typ);
12210 while Present (Old_C) loop
12211 if Chars ((Old_C)) = Name_uTag
12212 or else Chars ((Old_C)) = Name_uParent
12214 Append_Elmt (Old_C, Comp_List);
12217 Next_Component (Old_C);
12220 end Collect_Fixed_Components;
12222 ---------------------------
12223 -- Create_All_Components --
12224 ---------------------------
12226 procedure Create_All_Components is
12230 Comp := First_Elmt (Comp_List);
12231 while Present (Comp) loop
12232 Old_C := Node (Comp);
12233 New_C := Create_Component (Old_C);
12237 Constrain_Component_Type
12238 (Old_C, Subt, Decl_Node, Typ, Constraints));
12239 Set_Is_Public (New_C, Is_Public (Subt));
12243 end Create_All_Components;
12245 ----------------------
12246 -- Create_Component --
12247 ----------------------
12249 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
12250 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
12253 if Ekind (Old_Compon) = E_Discriminant
12254 and then Is_Completely_Hidden (Old_Compon)
12256 -- This is a shadow discriminant created for a discriminant of
12257 -- the parent type, which needs to be present in the subtype.
12258 -- Give the shadow discriminant an internal name that cannot
12259 -- conflict with that of visible components.
12261 Set_Chars (New_Compon, New_Internal_Name ('C'));
12264 -- Set the parent so we have a proper link for freezing etc. This is
12265 -- not a real parent pointer, since of course our parent does not own
12266 -- up to us and reference us, we are an illegitimate child of the
12267 -- original parent!
12269 Set_Parent (New_Compon, Parent (Old_Compon));
12271 -- If the old component's Esize was already determined and is a
12272 -- static value, then the new component simply inherits it. Otherwise
12273 -- the old component's size may require run-time determination, but
12274 -- the new component's size still might be statically determinable
12275 -- (if, for example it has a static constraint). In that case we want
12276 -- Layout_Type to recompute the component's size, so we reset its
12277 -- size and positional fields.
12279 if Frontend_Layout_On_Target
12280 and then not Known_Static_Esize (Old_Compon)
12282 Set_Esize (New_Compon, Uint_0);
12283 Init_Normalized_First_Bit (New_Compon);
12284 Init_Normalized_Position (New_Compon);
12285 Init_Normalized_Position_Max (New_Compon);
12288 -- We do not want this node marked as Comes_From_Source, since
12289 -- otherwise it would get first class status and a separate cross-
12290 -- reference line would be generated. Illegitimate children do not
12291 -- rate such recognition.
12293 Set_Comes_From_Source (New_Compon, False);
12295 -- But it is a real entity, and a birth certificate must be properly
12296 -- registered by entering it into the entity list.
12298 Enter_Name (New_Compon);
12301 end Create_Component;
12303 -----------------------
12304 -- Is_Variant_Record --
12305 -----------------------
12307 function Is_Variant_Record (T : Entity_Id) return Boolean is
12309 return Nkind (Parent (T)) = N_Full_Type_Declaration
12310 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
12311 and then Present (Component_List (Type_Definition (Parent (T))))
12314 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
12315 end Is_Variant_Record;
12317 -- Start of processing for Create_Constrained_Components
12320 pragma Assert (Subt /= Base_Type (Subt));
12321 pragma Assert (Typ = Base_Type (Typ));
12323 Set_First_Entity (Subt, Empty);
12324 Set_Last_Entity (Subt, Empty);
12326 -- Check whether constraint is fully static, in which case we can
12327 -- optimize the list of components.
12329 Discr_Val := First_Elmt (Constraints);
12330 while Present (Discr_Val) loop
12331 if not Is_OK_Static_Expression (Node (Discr_Val)) then
12332 Is_Static := False;
12336 Next_Elmt (Discr_Val);
12339 Set_Has_Static_Discriminants (Subt, Is_Static);
12343 -- Inherit the discriminants of the parent type
12345 Add_Discriminants : declare
12351 Old_C := First_Discriminant (Typ);
12353 while Present (Old_C) loop
12354 Num_Disc := Num_Disc + 1;
12355 New_C := Create_Component (Old_C);
12356 Set_Is_Public (New_C, Is_Public (Subt));
12357 Next_Discriminant (Old_C);
12360 -- For an untagged derived subtype, the number of discriminants may
12361 -- be smaller than the number of inherited discriminants, because
12362 -- several of them may be renamed by a single new discriminant or
12363 -- constrained. In this case, add the hidden discriminants back into
12364 -- the subtype, because they need to be present if the optimizer of
12365 -- the GCC 4.x back-end decides to break apart assignments between
12366 -- objects using the parent view into member-wise assignments.
12370 if Is_Derived_Type (Typ)
12371 and then not Is_Tagged_Type (Typ)
12373 Old_C := First_Stored_Discriminant (Typ);
12375 while Present (Old_C) loop
12376 Num_Gird := Num_Gird + 1;
12377 Next_Stored_Discriminant (Old_C);
12381 if Num_Gird > Num_Disc then
12383 -- Find out multiple uses of new discriminants, and add hidden
12384 -- components for the extra renamed discriminants. We recognize
12385 -- multiple uses through the Corresponding_Discriminant of a
12386 -- new discriminant: if it constrains several old discriminants,
12387 -- this field points to the last one in the parent type. The
12388 -- stored discriminants of the derived type have the same name
12389 -- as those of the parent.
12393 New_Discr : Entity_Id;
12394 Old_Discr : Entity_Id;
12397 Constr := First_Elmt (Stored_Constraint (Typ));
12398 Old_Discr := First_Stored_Discriminant (Typ);
12399 while Present (Constr) loop
12400 if Is_Entity_Name (Node (Constr))
12401 and then Ekind (Entity (Node (Constr))) = E_Discriminant
12403 New_Discr := Entity (Node (Constr));
12405 if Chars (Corresponding_Discriminant (New_Discr)) /=
12408 -- The new discriminant has been used to rename a
12409 -- subsequent old discriminant. Introduce a shadow
12410 -- component for the current old discriminant.
12412 New_C := Create_Component (Old_Discr);
12413 Set_Original_Record_Component (New_C, Old_Discr);
12417 -- The constraint has eliminated the old discriminant.
12418 -- Introduce a shadow component.
12420 New_C := Create_Component (Old_Discr);
12421 Set_Original_Record_Component (New_C, Old_Discr);
12424 Next_Elmt (Constr);
12425 Next_Stored_Discriminant (Old_Discr);
12429 end Add_Discriminants;
12432 and then Is_Variant_Record (Typ)
12434 Collect_Fixed_Components (Typ);
12436 Gather_Components (
12438 Component_List (Type_Definition (Parent (Typ))),
12439 Governed_By => Assoc_List,
12441 Report_Errors => Errors);
12442 pragma Assert (not Errors);
12444 Create_All_Components;
12446 -- If the subtype declaration is created for a tagged type derivation
12447 -- with constraints, we retrieve the record definition of the parent
12448 -- type to select the components of the proper variant.
12451 and then Is_Tagged_Type (Typ)
12452 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
12454 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
12455 and then Is_Variant_Record (Parent_Type)
12457 Collect_Fixed_Components (Typ);
12459 Gather_Components (
12461 Component_List (Type_Definition (Parent (Parent_Type))),
12462 Governed_By => Assoc_List,
12464 Report_Errors => Errors);
12465 pragma Assert (not Errors);
12467 -- If the tagged derivation has a type extension, collect all the
12468 -- new components therein.
12471 (Record_Extension_Part (Type_Definition (Parent (Typ))))
12473 Old_C := First_Component (Typ);
12474 while Present (Old_C) loop
12475 if Original_Record_Component (Old_C) = Old_C
12476 and then Chars (Old_C) /= Name_uTag
12477 and then Chars (Old_C) /= Name_uParent
12479 Append_Elmt (Old_C, Comp_List);
12482 Next_Component (Old_C);
12486 Create_All_Components;
12489 -- If discriminants are not static, or if this is a multi-level type
12490 -- extension, we have to include all components of the parent type.
12492 Old_C := First_Component (Typ);
12493 while Present (Old_C) loop
12494 New_C := Create_Component (Old_C);
12498 Constrain_Component_Type
12499 (Old_C, Subt, Decl_Node, Typ, Constraints));
12500 Set_Is_Public (New_C, Is_Public (Subt));
12502 Next_Component (Old_C);
12507 end Create_Constrained_Components;
12509 ------------------------------------------
12510 -- Decimal_Fixed_Point_Type_Declaration --
12511 ------------------------------------------
12513 procedure Decimal_Fixed_Point_Type_Declaration
12517 Loc : constant Source_Ptr := Sloc (Def);
12518 Digs_Expr : constant Node_Id := Digits_Expression (Def);
12519 Delta_Expr : constant Node_Id := Delta_Expression (Def);
12520 Implicit_Base : Entity_Id;
12527 Check_SPARK_Restriction
12528 ("decimal fixed point type is not allowed", Def);
12529 Check_Restriction (No_Fixed_Point, Def);
12531 -- Create implicit base type
12534 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
12535 Set_Etype (Implicit_Base, Implicit_Base);
12537 -- Analyze and process delta expression
12539 Analyze_And_Resolve (Delta_Expr, Universal_Real);
12541 Check_Delta_Expression (Delta_Expr);
12542 Delta_Val := Expr_Value_R (Delta_Expr);
12544 -- Check delta is power of 10, and determine scale value from it
12550 Scale_Val := Uint_0;
12553 if Val < Ureal_1 then
12554 while Val < Ureal_1 loop
12555 Val := Val * Ureal_10;
12556 Scale_Val := Scale_Val + 1;
12559 if Scale_Val > 18 then
12560 Error_Msg_N ("scale exceeds maximum value of 18", Def);
12561 Scale_Val := UI_From_Int (+18);
12565 while Val > Ureal_1 loop
12566 Val := Val / Ureal_10;
12567 Scale_Val := Scale_Val - 1;
12570 if Scale_Val < -18 then
12571 Error_Msg_N ("scale is less than minimum value of -18", Def);
12572 Scale_Val := UI_From_Int (-18);
12576 if Val /= Ureal_1 then
12577 Error_Msg_N ("delta expression must be a power of 10", Def);
12578 Delta_Val := Ureal_10 ** (-Scale_Val);
12582 -- Set delta, scale and small (small = delta for decimal type)
12584 Set_Delta_Value (Implicit_Base, Delta_Val);
12585 Set_Scale_Value (Implicit_Base, Scale_Val);
12586 Set_Small_Value (Implicit_Base, Delta_Val);
12588 -- Analyze and process digits expression
12590 Analyze_And_Resolve (Digs_Expr, Any_Integer);
12591 Check_Digits_Expression (Digs_Expr);
12592 Digs_Val := Expr_Value (Digs_Expr);
12594 if Digs_Val > 18 then
12595 Digs_Val := UI_From_Int (+18);
12596 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
12599 Set_Digits_Value (Implicit_Base, Digs_Val);
12600 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
12602 -- Set range of base type from digits value for now. This will be
12603 -- expanded to represent the true underlying base range by Freeze.
12605 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
12607 -- Note: We leave size as zero for now, size will be set at freeze
12608 -- time. We have to do this for ordinary fixed-point, because the size
12609 -- depends on the specified small, and we might as well do the same for
12610 -- decimal fixed-point.
12612 pragma Assert (Esize (Implicit_Base) = Uint_0);
12614 -- If there are bounds given in the declaration use them as the
12615 -- bounds of the first named subtype.
12617 if Present (Real_Range_Specification (Def)) then
12619 RRS : constant Node_Id := Real_Range_Specification (Def);
12620 Low : constant Node_Id := Low_Bound (RRS);
12621 High : constant Node_Id := High_Bound (RRS);
12626 Analyze_And_Resolve (Low, Any_Real);
12627 Analyze_And_Resolve (High, Any_Real);
12628 Check_Real_Bound (Low);
12629 Check_Real_Bound (High);
12630 Low_Val := Expr_Value_R (Low);
12631 High_Val := Expr_Value_R (High);
12633 if Low_Val < (-Bound_Val) then
12635 ("range low bound too small for digits value", Low);
12636 Low_Val := -Bound_Val;
12639 if High_Val > Bound_Val then
12641 ("range high bound too large for digits value", High);
12642 High_Val := Bound_Val;
12645 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
12648 -- If no explicit range, use range that corresponds to given
12649 -- digits value. This will end up as the final range for the
12653 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
12656 -- Complete entity for first subtype
12658 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
12659 Set_Etype (T, Implicit_Base);
12660 Set_Size_Info (T, Implicit_Base);
12661 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
12662 Set_Digits_Value (T, Digs_Val);
12663 Set_Delta_Value (T, Delta_Val);
12664 Set_Small_Value (T, Delta_Val);
12665 Set_Scale_Value (T, Scale_Val);
12666 Set_Is_Constrained (T);
12667 end Decimal_Fixed_Point_Type_Declaration;
12669 -----------------------------------
12670 -- Derive_Progenitor_Subprograms --
12671 -----------------------------------
12673 procedure Derive_Progenitor_Subprograms
12674 (Parent_Type : Entity_Id;
12675 Tagged_Type : Entity_Id)
12680 Iface_Elmt : Elmt_Id;
12681 Iface_Subp : Entity_Id;
12682 New_Subp : Entity_Id := Empty;
12683 Prim_Elmt : Elmt_Id;
12688 pragma Assert (Ada_Version >= Ada_2005
12689 and then Is_Record_Type (Tagged_Type)
12690 and then Is_Tagged_Type (Tagged_Type)
12691 and then Has_Interfaces (Tagged_Type));
12693 -- Step 1: Transfer to the full-view primitives associated with the
12694 -- partial-view that cover interface primitives. Conceptually this
12695 -- work should be done later by Process_Full_View; done here to
12696 -- simplify its implementation at later stages. It can be safely
12697 -- done here because interfaces must be visible in the partial and
12698 -- private view (RM 7.3(7.3/2)).
12700 -- Small optimization: This work is only required if the parent is
12701 -- abstract. If the tagged type is not abstract, it cannot have
12702 -- abstract primitives (the only entities in the list of primitives of
12703 -- non-abstract tagged types that can reference abstract primitives
12704 -- through its Alias attribute are the internal entities that have
12705 -- attribute Interface_Alias, and these entities are generated later
12706 -- by Add_Internal_Interface_Entities).
12708 if In_Private_Part (Current_Scope)
12709 and then Is_Abstract_Type (Parent_Type)
12711 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
12712 while Present (Elmt) loop
12713 Subp := Node (Elmt);
12715 -- At this stage it is not possible to have entities in the list
12716 -- of primitives that have attribute Interface_Alias
12718 pragma Assert (No (Interface_Alias (Subp)));
12720 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
12722 if Is_Interface (Typ) then
12723 E := Find_Primitive_Covering_Interface
12724 (Tagged_Type => Tagged_Type,
12725 Iface_Prim => Subp);
12728 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
12730 Replace_Elmt (Elmt, E);
12731 Remove_Homonym (Subp);
12739 -- Step 2: Add primitives of progenitors that are not implemented by
12740 -- parents of Tagged_Type
12742 if Present (Interfaces (Base_Type (Tagged_Type))) then
12743 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
12744 while Present (Iface_Elmt) loop
12745 Iface := Node (Iface_Elmt);
12747 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
12748 while Present (Prim_Elmt) loop
12749 Iface_Subp := Node (Prim_Elmt);
12751 -- Exclude derivation of predefined primitives except those
12752 -- that come from source. Required to catch declarations of
12753 -- equality operators of interfaces. For example:
12755 -- type Iface is interface;
12756 -- function "=" (Left, Right : Iface) return Boolean;
12758 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
12759 or else Comes_From_Source (Iface_Subp)
12761 E := Find_Primitive_Covering_Interface
12762 (Tagged_Type => Tagged_Type,
12763 Iface_Prim => Iface_Subp);
12765 -- If not found we derive a new primitive leaving its alias
12766 -- attribute referencing the interface primitive
12770 (New_Subp, Iface_Subp, Tagged_Type, Iface);
12772 -- Ada 2012 (AI05-0197): If the covering primitive's name
12773 -- differs from the name of the interface primitive then it
12774 -- is a private primitive inherited from a parent type. In
12775 -- such case, given that Tagged_Type covers the interface,
12776 -- the inherited private primitive becomes visible. For such
12777 -- purpose we add a new entity that renames the inherited
12778 -- private primitive.
12780 elsif Chars (E) /= Chars (Iface_Subp) then
12781 pragma Assert (Has_Suffix (E, 'P'));
12783 (New_Subp, Iface_Subp, Tagged_Type, Iface);
12784 Set_Alias (New_Subp, E);
12785 Set_Is_Abstract_Subprogram (New_Subp,
12786 Is_Abstract_Subprogram (E));
12788 -- Propagate to the full view interface entities associated
12789 -- with the partial view
12791 elsif In_Private_Part (Current_Scope)
12792 and then Present (Alias (E))
12793 and then Alias (E) = Iface_Subp
12795 List_Containing (Parent (E)) /=
12796 Private_Declarations
12798 (Unit_Declaration_Node (Current_Scope)))
12800 Append_Elmt (E, Primitive_Operations (Tagged_Type));
12804 Next_Elmt (Prim_Elmt);
12807 Next_Elmt (Iface_Elmt);
12810 end Derive_Progenitor_Subprograms;
12812 -----------------------
12813 -- Derive_Subprogram --
12814 -----------------------
12816 procedure Derive_Subprogram
12817 (New_Subp : in out Entity_Id;
12818 Parent_Subp : Entity_Id;
12819 Derived_Type : Entity_Id;
12820 Parent_Type : Entity_Id;
12821 Actual_Subp : Entity_Id := Empty)
12823 Formal : Entity_Id;
12824 -- Formal parameter of parent primitive operation
12826 Formal_Of_Actual : Entity_Id;
12827 -- Formal parameter of actual operation, when the derivation is to
12828 -- create a renaming for a primitive operation of an actual in an
12831 New_Formal : Entity_Id;
12832 -- Formal of inherited operation
12834 Visible_Subp : Entity_Id := Parent_Subp;
12836 function Is_Private_Overriding return Boolean;
12837 -- If Subp is a private overriding of a visible operation, the inherited
12838 -- operation derives from the overridden op (even though its body is the
12839 -- overriding one) and the inherited operation is visible now. See
12840 -- sem_disp to see the full details of the handling of the overridden
12841 -- subprogram, which is removed from the list of primitive operations of
12842 -- the type. The overridden subprogram is saved locally in Visible_Subp,
12843 -- and used to diagnose abstract operations that need overriding in the
12846 procedure Replace_Type (Id, New_Id : Entity_Id);
12847 -- When the type is an anonymous access type, create a new access type
12848 -- designating the derived type.
12850 procedure Set_Derived_Name;
12851 -- This procedure sets the appropriate Chars name for New_Subp. This
12852 -- is normally just a copy of the parent name. An exception arises for
12853 -- type support subprograms, where the name is changed to reflect the
12854 -- name of the derived type, e.g. if type foo is derived from type bar,
12855 -- then a procedure barDA is derived with a name fooDA.
12857 ---------------------------
12858 -- Is_Private_Overriding --
12859 ---------------------------
12861 function Is_Private_Overriding return Boolean is
12865 -- If the parent is not a dispatching operation there is no
12866 -- need to investigate overridings
12868 if not Is_Dispatching_Operation (Parent_Subp) then
12872 -- The visible operation that is overridden is a homonym of the
12873 -- parent subprogram. We scan the homonym chain to find the one
12874 -- whose alias is the subprogram we are deriving.
12876 Prev := Current_Entity (Parent_Subp);
12877 while Present (Prev) loop
12878 if Ekind (Prev) = Ekind (Parent_Subp)
12879 and then Alias (Prev) = Parent_Subp
12880 and then Scope (Parent_Subp) = Scope (Prev)
12881 and then not Is_Hidden (Prev)
12883 Visible_Subp := Prev;
12887 Prev := Homonym (Prev);
12891 end Is_Private_Overriding;
12897 procedure Replace_Type (Id, New_Id : Entity_Id) is
12898 Acc_Type : Entity_Id;
12899 Par : constant Node_Id := Parent (Derived_Type);
12902 -- When the type is an anonymous access type, create a new access
12903 -- type designating the derived type. This itype must be elaborated
12904 -- at the point of the derivation, not on subsequent calls that may
12905 -- be out of the proper scope for Gigi, so we insert a reference to
12906 -- it after the derivation.
12908 if Ekind (Etype (Id)) = E_Anonymous_Access_Type then
12910 Desig_Typ : Entity_Id := Designated_Type (Etype (Id));
12913 if Ekind (Desig_Typ) = E_Record_Type_With_Private
12914 and then Present (Full_View (Desig_Typ))
12915 and then not Is_Private_Type (Parent_Type)
12917 Desig_Typ := Full_View (Desig_Typ);
12920 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
12922 -- Ada 2005 (AI-251): Handle also derivations of abstract
12923 -- interface primitives.
12925 or else (Is_Interface (Desig_Typ)
12926 and then not Is_Class_Wide_Type (Desig_Typ))
12928 Acc_Type := New_Copy (Etype (Id));
12929 Set_Etype (Acc_Type, Acc_Type);
12930 Set_Scope (Acc_Type, New_Subp);
12932 -- Compute size of anonymous access type
12934 if Is_Array_Type (Desig_Typ)
12935 and then not Is_Constrained (Desig_Typ)
12937 Init_Size (Acc_Type, 2 * System_Address_Size);
12939 Init_Size (Acc_Type, System_Address_Size);
12942 Init_Alignment (Acc_Type);
12943 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
12945 Set_Etype (New_Id, Acc_Type);
12946 Set_Scope (New_Id, New_Subp);
12948 -- Create a reference to it
12949 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
12952 Set_Etype (New_Id, Etype (Id));
12956 elsif Base_Type (Etype (Id)) = Base_Type (Parent_Type)
12958 (Ekind (Etype (Id)) = E_Record_Type_With_Private
12959 and then Present (Full_View (Etype (Id)))
12961 Base_Type (Full_View (Etype (Id))) = Base_Type (Parent_Type))
12963 -- Constraint checks on formals are generated during expansion,
12964 -- based on the signature of the original subprogram. The bounds
12965 -- of the derived type are not relevant, and thus we can use
12966 -- the base type for the formals. However, the return type may be
12967 -- used in a context that requires that the proper static bounds
12968 -- be used (a case statement, for example) and for those cases
12969 -- we must use the derived type (first subtype), not its base.
12971 -- If the derived_type_definition has no constraints, we know that
12972 -- the derived type has the same constraints as the first subtype
12973 -- of the parent, and we can also use it rather than its base,
12974 -- which can lead to more efficient code.
12976 if Etype (Id) = Parent_Type then
12977 if Is_Scalar_Type (Parent_Type)
12979 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
12981 Set_Etype (New_Id, Derived_Type);
12983 elsif Nkind (Par) = N_Full_Type_Declaration
12985 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
12988 (Subtype_Indication (Type_Definition (Par)))
12990 Set_Etype (New_Id, Derived_Type);
12993 Set_Etype (New_Id, Base_Type (Derived_Type));
12997 Set_Etype (New_Id, Base_Type (Derived_Type));
13001 Set_Etype (New_Id, Etype (Id));
13005 ----------------------
13006 -- Set_Derived_Name --
13007 ----------------------
13009 procedure Set_Derived_Name is
13010 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
13012 if Nm = TSS_Null then
13013 Set_Chars (New_Subp, Chars (Parent_Subp));
13015 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
13017 end Set_Derived_Name;
13019 -- Start of processing for Derive_Subprogram
13023 New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
13024 Set_Ekind (New_Subp, Ekind (Parent_Subp));
13026 -- Check whether the inherited subprogram is a private operation that
13027 -- should be inherited but not yet made visible. Such subprograms can
13028 -- become visible at a later point (e.g., the private part of a public
13029 -- child unit) via Declare_Inherited_Private_Subprograms. If the
13030 -- following predicate is true, then this is not such a private
13031 -- operation and the subprogram simply inherits the name of the parent
13032 -- subprogram. Note the special check for the names of controlled
13033 -- operations, which are currently exempted from being inherited with
13034 -- a hidden name because they must be findable for generation of
13035 -- implicit run-time calls.
13037 if not Is_Hidden (Parent_Subp)
13038 or else Is_Internal (Parent_Subp)
13039 or else Is_Private_Overriding
13040 or else Is_Internal_Name (Chars (Parent_Subp))
13041 or else Chars (Parent_Subp) = Name_Initialize
13042 or else Chars (Parent_Subp) = Name_Adjust
13043 or else Chars (Parent_Subp) = Name_Finalize
13047 -- An inherited dispatching equality will be overridden by an internally
13048 -- generated one, or by an explicit one, so preserve its name and thus
13049 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
13050 -- private operation it may become invisible if the full view has
13051 -- progenitors, and the dispatch table will be malformed.
13052 -- We check that the type is limited to handle the anomalous declaration
13053 -- of Limited_Controlled, which is derived from a non-limited type, and
13054 -- which is handled specially elsewhere as well.
13056 elsif Chars (Parent_Subp) = Name_Op_Eq
13057 and then Is_Dispatching_Operation (Parent_Subp)
13058 and then Etype (Parent_Subp) = Standard_Boolean
13059 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
13061 Etype (First_Formal (Parent_Subp)) =
13062 Etype (Next_Formal (First_Formal (Parent_Subp)))
13066 -- If parent is hidden, this can be a regular derivation if the
13067 -- parent is immediately visible in a non-instantiating context,
13068 -- or if we are in the private part of an instance. This test
13069 -- should still be refined ???
13071 -- The test for In_Instance_Not_Visible avoids inheriting the derived
13072 -- operation as a non-visible operation in cases where the parent
13073 -- subprogram might not be visible now, but was visible within the
13074 -- original generic, so it would be wrong to make the inherited
13075 -- subprogram non-visible now. (Not clear if this test is fully
13076 -- correct; are there any cases where we should declare the inherited
13077 -- operation as not visible to avoid it being overridden, e.g., when
13078 -- the parent type is a generic actual with private primitives ???)
13080 -- (they should be treated the same as other private inherited
13081 -- subprograms, but it's not clear how to do this cleanly). ???
13083 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
13084 and then Is_Immediately_Visible (Parent_Subp)
13085 and then not In_Instance)
13086 or else In_Instance_Not_Visible
13090 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
13091 -- overrides an interface primitive because interface primitives
13092 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
13094 elsif Ada_Version >= Ada_2005
13095 and then Is_Dispatching_Operation (Parent_Subp)
13096 and then Covers_Some_Interface (Parent_Subp)
13100 -- Otherwise, the type is inheriting a private operation, so enter
13101 -- it with a special name so it can't be overridden.
13104 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
13107 Set_Parent (New_Subp, Parent (Derived_Type));
13109 if Present (Actual_Subp) then
13110 Replace_Type (Actual_Subp, New_Subp);
13112 Replace_Type (Parent_Subp, New_Subp);
13115 Conditional_Delay (New_Subp, Parent_Subp);
13117 -- If we are creating a renaming for a primitive operation of an
13118 -- actual of a generic derived type, we must examine the signature
13119 -- of the actual primitive, not that of the generic formal, which for
13120 -- example may be an interface. However the name and initial value
13121 -- of the inherited operation are those of the formal primitive.
13123 Formal := First_Formal (Parent_Subp);
13125 if Present (Actual_Subp) then
13126 Formal_Of_Actual := First_Formal (Actual_Subp);
13128 Formal_Of_Actual := Empty;
13131 while Present (Formal) loop
13132 New_Formal := New_Copy (Formal);
13134 -- Normally we do not go copying parents, but in the case of
13135 -- formals, we need to link up to the declaration (which is the
13136 -- parameter specification), and it is fine to link up to the
13137 -- original formal's parameter specification in this case.
13139 Set_Parent (New_Formal, Parent (Formal));
13140 Append_Entity (New_Formal, New_Subp);
13142 if Present (Formal_Of_Actual) then
13143 Replace_Type (Formal_Of_Actual, New_Formal);
13144 Next_Formal (Formal_Of_Actual);
13146 Replace_Type (Formal, New_Formal);
13149 Next_Formal (Formal);
13152 -- If this derivation corresponds to a tagged generic actual, then
13153 -- primitive operations rename those of the actual. Otherwise the
13154 -- primitive operations rename those of the parent type, If the parent
13155 -- renames an intrinsic operator, so does the new subprogram. We except
13156 -- concatenation, which is always properly typed, and does not get
13157 -- expanded as other intrinsic operations.
13159 if No (Actual_Subp) then
13160 if Is_Intrinsic_Subprogram (Parent_Subp) then
13161 Set_Is_Intrinsic_Subprogram (New_Subp);
13163 if Present (Alias (Parent_Subp))
13164 and then Chars (Parent_Subp) /= Name_Op_Concat
13166 Set_Alias (New_Subp, Alias (Parent_Subp));
13168 Set_Alias (New_Subp, Parent_Subp);
13172 Set_Alias (New_Subp, Parent_Subp);
13176 Set_Alias (New_Subp, Actual_Subp);
13179 -- Derived subprograms of a tagged type must inherit the convention
13180 -- of the parent subprogram (a requirement of AI-117). Derived
13181 -- subprograms of untagged types simply get convention Ada by default.
13183 if Is_Tagged_Type (Derived_Type) then
13184 Set_Convention (New_Subp, Convention (Parent_Subp));
13187 -- Predefined controlled operations retain their name even if the parent
13188 -- is hidden (see above), but they are not primitive operations if the
13189 -- ancestor is not visible, for example if the parent is a private
13190 -- extension completed with a controlled extension. Note that a full
13191 -- type that is controlled can break privacy: the flag Is_Controlled is
13192 -- set on both views of the type.
13194 if Is_Controlled (Parent_Type)
13196 (Chars (Parent_Subp) = Name_Initialize
13197 or else Chars (Parent_Subp) = Name_Adjust
13198 or else Chars (Parent_Subp) = Name_Finalize)
13199 and then Is_Hidden (Parent_Subp)
13200 and then not Is_Visibly_Controlled (Parent_Type)
13202 Set_Is_Hidden (New_Subp);
13205 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
13206 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
13208 if Ekind (Parent_Subp) = E_Procedure then
13209 Set_Is_Valued_Procedure
13210 (New_Subp, Is_Valued_Procedure (Parent_Subp));
13212 Set_Has_Controlling_Result
13213 (New_Subp, Has_Controlling_Result (Parent_Subp));
13216 -- No_Return must be inherited properly. If this is overridden in the
13217 -- case of a dispatching operation, then a check is made in Sem_Disp
13218 -- that the overriding operation is also No_Return (no such check is
13219 -- required for the case of non-dispatching operation.
13221 Set_No_Return (New_Subp, No_Return (Parent_Subp));
13223 -- A derived function with a controlling result is abstract. If the
13224 -- Derived_Type is a nonabstract formal generic derived type, then
13225 -- inherited operations are not abstract: the required check is done at
13226 -- instantiation time. If the derivation is for a generic actual, the
13227 -- function is not abstract unless the actual is.
13229 if Is_Generic_Type (Derived_Type)
13230 and then not Is_Abstract_Type (Derived_Type)
13234 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
13235 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
13237 elsif Ada_Version >= Ada_2005
13238 and then (Is_Abstract_Subprogram (Alias (New_Subp))
13239 or else (Is_Tagged_Type (Derived_Type)
13240 and then Etype (New_Subp) = Derived_Type
13241 and then not Is_Null_Extension (Derived_Type))
13242 or else (Is_Tagged_Type (Derived_Type)
13243 and then Ekind (Etype (New_Subp)) =
13244 E_Anonymous_Access_Type
13245 and then Designated_Type (Etype (New_Subp)) =
13247 and then not Is_Null_Extension (Derived_Type)))
13248 and then No (Actual_Subp)
13250 if not Is_Tagged_Type (Derived_Type)
13251 or else Is_Abstract_Type (Derived_Type)
13252 or else Is_Abstract_Subprogram (Alias (New_Subp))
13254 Set_Is_Abstract_Subprogram (New_Subp);
13256 Set_Requires_Overriding (New_Subp);
13259 elsif Ada_Version < Ada_2005
13260 and then (Is_Abstract_Subprogram (Alias (New_Subp))
13261 or else (Is_Tagged_Type (Derived_Type)
13262 and then Etype (New_Subp) = Derived_Type
13263 and then No (Actual_Subp)))
13265 Set_Is_Abstract_Subprogram (New_Subp);
13267 -- AI05-0097 : an inherited operation that dispatches on result is
13268 -- abstract if the derived type is abstract, even if the parent type
13269 -- is concrete and the derived type is a null extension.
13271 elsif Has_Controlling_Result (Alias (New_Subp))
13272 and then Is_Abstract_Type (Etype (New_Subp))
13274 Set_Is_Abstract_Subprogram (New_Subp);
13276 -- Finally, if the parent type is abstract we must verify that all
13277 -- inherited operations are either non-abstract or overridden, or that
13278 -- the derived type itself is abstract (this check is performed at the
13279 -- end of a package declaration, in Check_Abstract_Overriding). A
13280 -- private overriding in the parent type will not be visible in the
13281 -- derivation if we are not in an inner package or in a child unit of
13282 -- the parent type, in which case the abstractness of the inherited
13283 -- operation is carried to the new subprogram.
13285 elsif Is_Abstract_Type (Parent_Type)
13286 and then not In_Open_Scopes (Scope (Parent_Type))
13287 and then Is_Private_Overriding
13288 and then Is_Abstract_Subprogram (Visible_Subp)
13290 if No (Actual_Subp) then
13291 Set_Alias (New_Subp, Visible_Subp);
13292 Set_Is_Abstract_Subprogram (New_Subp, True);
13295 -- If this is a derivation for an instance of a formal derived
13296 -- type, abstractness comes from the primitive operation of the
13297 -- actual, not from the operation inherited from the ancestor.
13299 Set_Is_Abstract_Subprogram
13300 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
13304 New_Overloaded_Entity (New_Subp, Derived_Type);
13306 -- Check for case of a derived subprogram for the instantiation of a
13307 -- formal derived tagged type, if so mark the subprogram as dispatching
13308 -- and inherit the dispatching attributes of the parent subprogram. The
13309 -- derived subprogram is effectively renaming of the actual subprogram,
13310 -- so it needs to have the same attributes as the actual.
13312 if Present (Actual_Subp)
13313 and then Is_Dispatching_Operation (Parent_Subp)
13315 Set_Is_Dispatching_Operation (New_Subp);
13317 if Present (DTC_Entity (Parent_Subp)) then
13318 Set_DTC_Entity (New_Subp, DTC_Entity (Parent_Subp));
13319 Set_DT_Position (New_Subp, DT_Position (Parent_Subp));
13323 -- Indicate that a derived subprogram does not require a body and that
13324 -- it does not require processing of default expressions.
13326 Set_Has_Completion (New_Subp);
13327 Set_Default_Expressions_Processed (New_Subp);
13329 if Ekind (New_Subp) = E_Function then
13330 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
13332 end Derive_Subprogram;
13334 ------------------------
13335 -- Derive_Subprograms --
13336 ------------------------
13338 procedure Derive_Subprograms
13339 (Parent_Type : Entity_Id;
13340 Derived_Type : Entity_Id;
13341 Generic_Actual : Entity_Id := Empty)
13343 Op_List : constant Elist_Id :=
13344 Collect_Primitive_Operations (Parent_Type);
13346 function Check_Derived_Type return Boolean;
13347 -- Check that all the entities derived from Parent_Type are found in
13348 -- the list of primitives of Derived_Type exactly in the same order.
13350 procedure Derive_Interface_Subprogram
13351 (New_Subp : in out Entity_Id;
13353 Actual_Subp : Entity_Id);
13354 -- Derive New_Subp from the ultimate alias of the parent subprogram Subp
13355 -- (which is an interface primitive). If Generic_Actual is present then
13356 -- Actual_Subp is the actual subprogram corresponding with the generic
13357 -- subprogram Subp.
13359 function Check_Derived_Type return Boolean is
13363 New_Subp : Entity_Id;
13368 -- Traverse list of entities in the current scope searching for
13369 -- an incomplete type whose full-view is derived type
13371 E := First_Entity (Scope (Derived_Type));
13373 and then E /= Derived_Type
13375 if Ekind (E) = E_Incomplete_Type
13376 and then Present (Full_View (E))
13377 and then Full_View (E) = Derived_Type
13379 -- Disable this test if Derived_Type completes an incomplete
13380 -- type because in such case more primitives can be added
13381 -- later to the list of primitives of Derived_Type by routine
13382 -- Process_Incomplete_Dependents
13387 E := Next_Entity (E);
13390 List := Collect_Primitive_Operations (Derived_Type);
13391 Elmt := First_Elmt (List);
13393 Op_Elmt := First_Elmt (Op_List);
13394 while Present (Op_Elmt) loop
13395 Subp := Node (Op_Elmt);
13396 New_Subp := Node (Elmt);
13398 -- At this early stage Derived_Type has no entities with attribute
13399 -- Interface_Alias. In addition, such primitives are always
13400 -- located at the end of the list of primitives of Parent_Type.
13401 -- Therefore, if found we can safely stop processing pending
13404 exit when Present (Interface_Alias (Subp));
13406 -- Handle hidden entities
13408 if not Is_Predefined_Dispatching_Operation (Subp)
13409 and then Is_Hidden (Subp)
13411 if Present (New_Subp)
13412 and then Primitive_Names_Match (Subp, New_Subp)
13418 if not Present (New_Subp)
13419 or else Ekind (Subp) /= Ekind (New_Subp)
13420 or else not Primitive_Names_Match (Subp, New_Subp)
13428 Next_Elmt (Op_Elmt);
13432 end Check_Derived_Type;
13434 ---------------------------------
13435 -- Derive_Interface_Subprogram --
13436 ---------------------------------
13438 procedure Derive_Interface_Subprogram
13439 (New_Subp : in out Entity_Id;
13441 Actual_Subp : Entity_Id)
13443 Iface_Subp : constant Entity_Id := Ultimate_Alias (Subp);
13444 Iface_Type : constant Entity_Id := Find_Dispatching_Type (Iface_Subp);
13447 pragma Assert (Is_Interface (Iface_Type));
13450 (New_Subp => New_Subp,
13451 Parent_Subp => Iface_Subp,
13452 Derived_Type => Derived_Type,
13453 Parent_Type => Iface_Type,
13454 Actual_Subp => Actual_Subp);
13456 -- Given that this new interface entity corresponds with a primitive
13457 -- of the parent that was not overridden we must leave it associated
13458 -- with its parent primitive to ensure that it will share the same
13459 -- dispatch table slot when overridden.
13461 if No (Actual_Subp) then
13462 Set_Alias (New_Subp, Subp);
13464 -- For instantiations this is not needed since the previous call to
13465 -- Derive_Subprogram leaves the entity well decorated.
13468 pragma Assert (Alias (New_Subp) = Actual_Subp);
13471 end Derive_Interface_Subprogram;
13475 Alias_Subp : Entity_Id;
13476 Act_List : Elist_Id;
13477 Act_Elmt : Elmt_Id := No_Elmt;
13478 Act_Subp : Entity_Id := Empty;
13480 Need_Search : Boolean := False;
13481 New_Subp : Entity_Id := Empty;
13482 Parent_Base : Entity_Id;
13485 -- Start of processing for Derive_Subprograms
13488 if Ekind (Parent_Type) = E_Record_Type_With_Private
13489 and then Has_Discriminants (Parent_Type)
13490 and then Present (Full_View (Parent_Type))
13492 Parent_Base := Full_View (Parent_Type);
13494 Parent_Base := Parent_Type;
13497 if Present (Generic_Actual) then
13498 Act_List := Collect_Primitive_Operations (Generic_Actual);
13499 Act_Elmt := First_Elmt (Act_List);
13502 -- Derive primitives inherited from the parent. Note that if the generic
13503 -- actual is present, this is not really a type derivation, it is a
13504 -- completion within an instance.
13506 -- Case 1: Derived_Type does not implement interfaces
13508 if not Is_Tagged_Type (Derived_Type)
13509 or else (not Has_Interfaces (Derived_Type)
13510 and then not (Present (Generic_Actual)
13512 Has_Interfaces (Generic_Actual)))
13514 Elmt := First_Elmt (Op_List);
13515 while Present (Elmt) loop
13516 Subp := Node (Elmt);
13518 -- Literals are derived earlier in the process of building the
13519 -- derived type, and are skipped here.
13521 if Ekind (Subp) = E_Enumeration_Literal then
13524 -- The actual is a direct descendant and the common primitive
13525 -- operations appear in the same order.
13527 -- If the generic parent type is present, the derived type is an
13528 -- instance of a formal derived type, and within the instance its
13529 -- operations are those of the actual. We derive from the formal
13530 -- type but make the inherited operations aliases of the
13531 -- corresponding operations of the actual.
13534 pragma Assert (No (Node (Act_Elmt))
13535 or else (Primitive_Names_Match (Subp, Node (Act_Elmt))
13537 Type_Conformant (Subp, Node (Act_Elmt),
13538 Skip_Controlling_Formals => True)));
13541 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
13543 if Present (Act_Elmt) then
13544 Next_Elmt (Act_Elmt);
13551 -- Case 2: Derived_Type implements interfaces
13554 -- If the parent type has no predefined primitives we remove
13555 -- predefined primitives from the list of primitives of generic
13556 -- actual to simplify the complexity of this algorithm.
13558 if Present (Generic_Actual) then
13560 Has_Predefined_Primitives : Boolean := False;
13563 -- Check if the parent type has predefined primitives
13565 Elmt := First_Elmt (Op_List);
13566 while Present (Elmt) loop
13567 Subp := Node (Elmt);
13569 if Is_Predefined_Dispatching_Operation (Subp)
13570 and then not Comes_From_Source (Ultimate_Alias (Subp))
13572 Has_Predefined_Primitives := True;
13579 -- Remove predefined primitives of Generic_Actual. We must use
13580 -- an auxiliary list because in case of tagged types the value
13581 -- returned by Collect_Primitive_Operations is the value stored
13582 -- in its Primitive_Operations attribute (and we don't want to
13583 -- modify its current contents).
13585 if not Has_Predefined_Primitives then
13587 Aux_List : constant Elist_Id := New_Elmt_List;
13590 Elmt := First_Elmt (Act_List);
13591 while Present (Elmt) loop
13592 Subp := Node (Elmt);
13594 if not Is_Predefined_Dispatching_Operation (Subp)
13595 or else Comes_From_Source (Subp)
13597 Append_Elmt (Subp, Aux_List);
13603 Act_List := Aux_List;
13607 Act_Elmt := First_Elmt (Act_List);
13608 Act_Subp := Node (Act_Elmt);
13612 -- Stage 1: If the generic actual is not present we derive the
13613 -- primitives inherited from the parent type. If the generic parent
13614 -- type is present, the derived type is an instance of a formal
13615 -- derived type, and within the instance its operations are those of
13616 -- the actual. We derive from the formal type but make the inherited
13617 -- operations aliases of the corresponding operations of the actual.
13619 Elmt := First_Elmt (Op_List);
13620 while Present (Elmt) loop
13621 Subp := Node (Elmt);
13622 Alias_Subp := Ultimate_Alias (Subp);
13624 -- Do not derive internal entities of the parent that link
13625 -- interface primitives with their covering primitive. These
13626 -- entities will be added to this type when frozen.
13628 if Present (Interface_Alias (Subp)) then
13632 -- If the generic actual is present find the corresponding
13633 -- operation in the generic actual. If the parent type is a
13634 -- direct ancestor of the derived type then, even if it is an
13635 -- interface, the operations are inherited from the primary
13636 -- dispatch table and are in the proper order. If we detect here
13637 -- that primitives are not in the same order we traverse the list
13638 -- of primitive operations of the actual to find the one that
13639 -- implements the interface primitive.
13643 (Present (Generic_Actual)
13644 and then Present (Act_Subp)
13646 (Primitive_Names_Match (Subp, Act_Subp)
13648 Type_Conformant (Subp, Act_Subp,
13649 Skip_Controlling_Formals => True)))
13651 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual));
13653 -- Remember that we need searching for all pending primitives
13655 Need_Search := True;
13657 -- Handle entities associated with interface primitives
13659 if Present (Alias_Subp)
13660 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
13661 and then not Is_Predefined_Dispatching_Operation (Subp)
13663 -- Search for the primitive in the homonym chain
13666 Find_Primitive_Covering_Interface
13667 (Tagged_Type => Generic_Actual,
13668 Iface_Prim => Alias_Subp);
13670 -- Previous search may not locate primitives covering
13671 -- interfaces defined in generics units or instantiations.
13672 -- (it fails if the covering primitive has formals whose
13673 -- type is also defined in generics or instantiations).
13674 -- In such case we search in the list of primitives of the
13675 -- generic actual for the internal entity that links the
13676 -- interface primitive and the covering primitive.
13679 and then Is_Generic_Type (Parent_Type)
13681 -- This code has been designed to handle only generic
13682 -- formals that implement interfaces that are defined
13683 -- in a generic unit or instantiation. If this code is
13684 -- needed for other cases we must review it because
13685 -- (given that it relies on Original_Location to locate
13686 -- the primitive of Generic_Actual that covers the
13687 -- interface) it could leave linked through attribute
13688 -- Alias entities of unrelated instantiations).
13692 (Scope (Find_Dispatching_Type (Alias_Subp)))
13694 Instantiation_Depth
13695 (Sloc (Find_Dispatching_Type (Alias_Subp))) > 0);
13698 Iface_Prim_Loc : constant Source_Ptr :=
13699 Original_Location (Sloc (Alias_Subp));
13704 First_Elmt (Primitive_Operations (Generic_Actual));
13706 Search : while Present (Elmt) loop
13707 Prim := Node (Elmt);
13709 if Present (Interface_Alias (Prim))
13710 and then Original_Location
13711 (Sloc (Interface_Alias (Prim)))
13714 Act_Subp := Alias (Prim);
13723 pragma Assert (Present (Act_Subp)
13724 or else Is_Abstract_Type (Generic_Actual)
13725 or else Serious_Errors_Detected > 0);
13727 -- Handle predefined primitives plus the rest of user-defined
13731 Act_Elmt := First_Elmt (Act_List);
13732 while Present (Act_Elmt) loop
13733 Act_Subp := Node (Act_Elmt);
13735 exit when Primitive_Names_Match (Subp, Act_Subp)
13736 and then Type_Conformant
13738 Skip_Controlling_Formals => True)
13739 and then No (Interface_Alias (Act_Subp));
13741 Next_Elmt (Act_Elmt);
13744 if No (Act_Elmt) then
13750 -- Case 1: If the parent is a limited interface then it has the
13751 -- predefined primitives of synchronized interfaces. However, the
13752 -- actual type may be a non-limited type and hence it does not
13753 -- have such primitives.
13755 if Present (Generic_Actual)
13756 and then not Present (Act_Subp)
13757 and then Is_Limited_Interface (Parent_Base)
13758 and then Is_Predefined_Interface_Primitive (Subp)
13762 -- Case 2: Inherit entities associated with interfaces that were
13763 -- not covered by the parent type. We exclude here null interface
13764 -- primitives because they do not need special management.
13766 -- We also exclude interface operations that are renamings. If the
13767 -- subprogram is an explicit renaming of an interface primitive,
13768 -- it is a regular primitive operation, and the presence of its
13769 -- alias is not relevant: it has to be derived like any other
13772 elsif Present (Alias (Subp))
13773 and then Nkind (Unit_Declaration_Node (Subp)) /=
13774 N_Subprogram_Renaming_Declaration
13775 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
13777 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
13778 and then Null_Present (Parent (Alias_Subp)))
13780 -- If this is an abstract private type then we transfer the
13781 -- derivation of the interface primitive from the partial view
13782 -- to the full view. This is safe because all the interfaces
13783 -- must be visible in the partial view. Done to avoid adding
13784 -- a new interface derivation to the private part of the
13785 -- enclosing package; otherwise this new derivation would be
13786 -- decorated as hidden when the analysis of the enclosing
13787 -- package completes.
13789 if Is_Abstract_Type (Derived_Type)
13790 and then In_Private_Part (Current_Scope)
13791 and then Has_Private_Declaration (Derived_Type)
13794 Partial_View : Entity_Id;
13799 Partial_View := First_Entity (Current_Scope);
13801 exit when No (Partial_View)
13802 or else (Has_Private_Declaration (Partial_View)
13804 Full_View (Partial_View) = Derived_Type);
13806 Next_Entity (Partial_View);
13809 -- If the partial view was not found then the source code
13810 -- has errors and the derivation is not needed.
13812 if Present (Partial_View) then
13814 First_Elmt (Primitive_Operations (Partial_View));
13815 while Present (Elmt) loop
13816 Ent := Node (Elmt);
13818 if Present (Alias (Ent))
13819 and then Ultimate_Alias (Ent) = Alias (Subp)
13822 (Ent, Primitive_Operations (Derived_Type));
13829 -- If the interface primitive was not found in the
13830 -- partial view then this interface primitive was
13831 -- overridden. We add a derivation to activate in
13832 -- Derive_Progenitor_Subprograms the machinery to
13836 Derive_Interface_Subprogram
13837 (New_Subp => New_Subp,
13839 Actual_Subp => Act_Subp);
13844 Derive_Interface_Subprogram
13845 (New_Subp => New_Subp,
13847 Actual_Subp => Act_Subp);
13850 -- Case 3: Common derivation
13854 (New_Subp => New_Subp,
13855 Parent_Subp => Subp,
13856 Derived_Type => Derived_Type,
13857 Parent_Type => Parent_Base,
13858 Actual_Subp => Act_Subp);
13861 -- No need to update Act_Elm if we must search for the
13862 -- corresponding operation in the generic actual
13865 and then Present (Act_Elmt)
13867 Next_Elmt (Act_Elmt);
13868 Act_Subp := Node (Act_Elmt);
13875 -- Inherit additional operations from progenitors. If the derived
13876 -- type is a generic actual, there are not new primitive operations
13877 -- for the type because it has those of the actual, and therefore
13878 -- nothing needs to be done. The renamings generated above are not
13879 -- primitive operations, and their purpose is simply to make the
13880 -- proper operations visible within an instantiation.
13882 if No (Generic_Actual) then
13883 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
13887 -- Final check: Direct descendants must have their primitives in the
13888 -- same order. We exclude from this test untagged types and instances
13889 -- of formal derived types. We skip this test if we have already
13890 -- reported serious errors in the sources.
13892 pragma Assert (not Is_Tagged_Type (Derived_Type)
13893 or else Present (Generic_Actual)
13894 or else Serious_Errors_Detected > 0
13895 or else Check_Derived_Type);
13896 end Derive_Subprograms;
13898 --------------------------------
13899 -- Derived_Standard_Character --
13900 --------------------------------
13902 procedure Derived_Standard_Character
13904 Parent_Type : Entity_Id;
13905 Derived_Type : Entity_Id)
13907 Loc : constant Source_Ptr := Sloc (N);
13908 Def : constant Node_Id := Type_Definition (N);
13909 Indic : constant Node_Id := Subtype_Indication (Def);
13910 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
13911 Implicit_Base : constant Entity_Id :=
13913 (E_Enumeration_Type, N, Derived_Type, 'B');
13919 Discard_Node (Process_Subtype (Indic, N));
13921 Set_Etype (Implicit_Base, Parent_Base);
13922 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
13923 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
13925 Set_Is_Character_Type (Implicit_Base, True);
13926 Set_Has_Delayed_Freeze (Implicit_Base);
13928 -- The bounds of the implicit base are the bounds of the parent base.
13929 -- Note that their type is the parent base.
13931 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
13932 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
13934 Set_Scalar_Range (Implicit_Base,
13937 High_Bound => Hi));
13939 Conditional_Delay (Derived_Type, Parent_Type);
13941 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
13942 Set_Etype (Derived_Type, Implicit_Base);
13943 Set_Size_Info (Derived_Type, Parent_Type);
13945 if Unknown_RM_Size (Derived_Type) then
13946 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
13949 Set_Is_Character_Type (Derived_Type, True);
13951 if Nkind (Indic) /= N_Subtype_Indication then
13953 -- If no explicit constraint, the bounds are those
13954 -- of the parent type.
13956 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
13957 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
13958 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
13961 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
13963 -- Because the implicit base is used in the conversion of the bounds, we
13964 -- have to freeze it now. This is similar to what is done for numeric
13965 -- types, and it equally suspicious, but otherwise a non-static bound
13966 -- will have a reference to an unfrozen type, which is rejected by Gigi
13967 -- (???). This requires specific care for definition of stream
13968 -- attributes. For details, see comments at the end of
13969 -- Build_Derived_Numeric_Type.
13971 Freeze_Before (N, Implicit_Base);
13972 end Derived_Standard_Character;
13974 ------------------------------
13975 -- Derived_Type_Declaration --
13976 ------------------------------
13978 procedure Derived_Type_Declaration
13981 Is_Completion : Boolean)
13983 Parent_Type : Entity_Id;
13985 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
13986 -- Check whether the parent type is a generic formal, or derives
13987 -- directly or indirectly from one.
13989 ------------------------
13990 -- Comes_From_Generic --
13991 ------------------------
13993 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
13995 if Is_Generic_Type (Typ) then
13998 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
14001 elsif Is_Private_Type (Typ)
14002 and then Present (Full_View (Typ))
14003 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
14007 elsif Is_Generic_Actual_Type (Typ) then
14013 end Comes_From_Generic;
14017 Def : constant Node_Id := Type_Definition (N);
14018 Iface_Def : Node_Id;
14019 Indic : constant Node_Id := Subtype_Indication (Def);
14020 Extension : constant Node_Id := Record_Extension_Part (Def);
14021 Parent_Node : Node_Id;
14024 -- Start of processing for Derived_Type_Declaration
14027 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
14029 -- Ada 2005 (AI-251): In case of interface derivation check that the
14030 -- parent is also an interface.
14032 if Interface_Present (Def) then
14033 Check_SPARK_Restriction ("interface is not allowed", Def);
14035 if not Is_Interface (Parent_Type) then
14036 Diagnose_Interface (Indic, Parent_Type);
14039 Parent_Node := Parent (Base_Type (Parent_Type));
14040 Iface_Def := Type_Definition (Parent_Node);
14042 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
14043 -- other limited interfaces.
14045 if Limited_Present (Def) then
14046 if Limited_Present (Iface_Def) then
14049 elsif Protected_Present (Iface_Def) then
14051 ("descendant of& must be declared"
14052 & " as a protected interface",
14055 elsif Synchronized_Present (Iface_Def) then
14057 ("descendant of& must be declared"
14058 & " as a synchronized interface",
14061 elsif Task_Present (Iface_Def) then
14063 ("descendant of& must be declared as a task interface",
14068 ("(Ada 2005) limited interface cannot "
14069 & "inherit from non-limited interface", Indic);
14072 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
14073 -- from non-limited or limited interfaces.
14075 elsif not Protected_Present (Def)
14076 and then not Synchronized_Present (Def)
14077 and then not Task_Present (Def)
14079 if Limited_Present (Iface_Def) then
14082 elsif Protected_Present (Iface_Def) then
14084 ("descendant of& must be declared"
14085 & " as a protected interface",
14088 elsif Synchronized_Present (Iface_Def) then
14090 ("descendant of& must be declared"
14091 & " as a synchronized interface",
14094 elsif Task_Present (Iface_Def) then
14096 ("descendant of& must be declared as a task interface",
14105 if Is_Tagged_Type (Parent_Type)
14106 and then Is_Concurrent_Type (Parent_Type)
14107 and then not Is_Interface (Parent_Type)
14110 ("parent type of a record extension cannot be "
14111 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
14112 Set_Etype (T, Any_Type);
14116 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
14119 if Is_Tagged_Type (Parent_Type)
14120 and then Is_Non_Empty_List (Interface_List (Def))
14127 Intf := First (Interface_List (Def));
14128 while Present (Intf) loop
14129 T := Find_Type_Of_Subtype_Indic (Intf);
14131 if not Is_Interface (T) then
14132 Diagnose_Interface (Intf, T);
14134 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
14135 -- a limited type from having a nonlimited progenitor.
14137 elsif (Limited_Present (Def)
14138 or else (not Is_Interface (Parent_Type)
14139 and then Is_Limited_Type (Parent_Type)))
14140 and then not Is_Limited_Interface (T)
14143 ("progenitor interface& of limited type must be limited",
14152 if Parent_Type = Any_Type
14153 or else Etype (Parent_Type) = Any_Type
14154 or else (Is_Class_Wide_Type (Parent_Type)
14155 and then Etype (Parent_Type) = T)
14157 -- If Parent_Type is undefined or illegal, make new type into a
14158 -- subtype of Any_Type, and set a few attributes to prevent cascaded
14159 -- errors. If this is a self-definition, emit error now.
14162 or else T = Etype (Parent_Type)
14164 Error_Msg_N ("type cannot be used in its own definition", Indic);
14167 Set_Ekind (T, Ekind (Parent_Type));
14168 Set_Etype (T, Any_Type);
14169 Set_Scalar_Range (T, Scalar_Range (Any_Type));
14171 if Is_Tagged_Type (T)
14172 and then Is_Record_Type (T)
14174 Set_Direct_Primitive_Operations (T, New_Elmt_List);
14180 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
14181 -- an interface is special because the list of interfaces in the full
14182 -- view can be given in any order. For example:
14184 -- type A is interface;
14185 -- type B is interface and A;
14186 -- type D is new B with private;
14188 -- type D is new A and B with null record; -- 1 --
14190 -- In this case we perform the following transformation of -1-:
14192 -- type D is new B and A with null record;
14194 -- If the parent of the full-view covers the parent of the partial-view
14195 -- we have two possible cases:
14197 -- 1) They have the same parent
14198 -- 2) The parent of the full-view implements some further interfaces
14200 -- In both cases we do not need to perform the transformation. In the
14201 -- first case the source program is correct and the transformation is
14202 -- not needed; in the second case the source program does not fulfill
14203 -- the no-hidden interfaces rule (AI-396) and the error will be reported
14206 -- This transformation not only simplifies the rest of the analysis of
14207 -- this type declaration but also simplifies the correct generation of
14208 -- the object layout to the expander.
14210 if In_Private_Part (Current_Scope)
14211 and then Is_Interface (Parent_Type)
14215 Partial_View : Entity_Id;
14216 Partial_View_Parent : Entity_Id;
14217 New_Iface : Node_Id;
14220 -- Look for the associated private type declaration
14222 Partial_View := First_Entity (Current_Scope);
14224 exit when No (Partial_View)
14225 or else (Has_Private_Declaration (Partial_View)
14226 and then Full_View (Partial_View) = T);
14228 Next_Entity (Partial_View);
14231 -- If the partial view was not found then the source code has
14232 -- errors and the transformation is not needed.
14234 if Present (Partial_View) then
14235 Partial_View_Parent := Etype (Partial_View);
14237 -- If the parent of the full-view covers the parent of the
14238 -- partial-view we have nothing else to do.
14240 if Interface_Present_In_Ancestor
14241 (Parent_Type, Partial_View_Parent)
14245 -- Traverse the list of interfaces of the full-view to look
14246 -- for the parent of the partial-view and perform the tree
14250 Iface := First (Interface_List (Def));
14251 while Present (Iface) loop
14252 if Etype (Iface) = Etype (Partial_View) then
14253 Rewrite (Subtype_Indication (Def),
14254 New_Copy (Subtype_Indication
14255 (Parent (Partial_View))));
14258 Make_Identifier (Sloc (N), Chars (Parent_Type));
14259 Append (New_Iface, Interface_List (Def));
14261 -- Analyze the transformed code
14263 Derived_Type_Declaration (T, N, Is_Completion);
14274 -- Only composite types other than array types are allowed to have
14275 -- discriminants. In SPARK, no types are allowed to have discriminants.
14277 if Present (Discriminant_Specifications (N)) then
14278 if (Is_Elementary_Type (Parent_Type)
14279 or else Is_Array_Type (Parent_Type))
14280 and then not Error_Posted (N)
14283 ("elementary or array type cannot have discriminants",
14284 Defining_Identifier (First (Discriminant_Specifications (N))));
14285 Set_Has_Discriminants (T, False);
14287 Check_SPARK_Restriction ("discriminant type is not allowed", N);
14291 -- In Ada 83, a derived type defined in a package specification cannot
14292 -- be used for further derivation until the end of its visible part.
14293 -- Note that derivation in the private part of the package is allowed.
14295 if Ada_Version = Ada_83
14296 and then Is_Derived_Type (Parent_Type)
14297 and then In_Visible_Part (Scope (Parent_Type))
14299 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
14301 ("(Ada 83): premature use of type for derivation", Indic);
14305 -- Check for early use of incomplete or private type
14307 if Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
14308 Error_Msg_N ("premature derivation of incomplete type", Indic);
14311 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
14312 and then not Comes_From_Generic (Parent_Type))
14313 or else Has_Private_Component (Parent_Type)
14315 -- The ancestor type of a formal type can be incomplete, in which
14316 -- case only the operations of the partial view are available in the
14317 -- generic. Subsequent checks may be required when the full view is
14318 -- analyzed to verify that a derivation from a tagged type has an
14321 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
14324 elsif No (Underlying_Type (Parent_Type))
14325 or else Has_Private_Component (Parent_Type)
14328 ("premature derivation of derived or private type", Indic);
14330 -- Flag the type itself as being in error, this prevents some
14331 -- nasty problems with subsequent uses of the malformed type.
14333 Set_Error_Posted (T);
14335 -- Check that within the immediate scope of an untagged partial
14336 -- view it's illegal to derive from the partial view if the
14337 -- full view is tagged. (7.3(7))
14339 -- We verify that the Parent_Type is a partial view by checking
14340 -- that it is not a Full_Type_Declaration (i.e. a private type or
14341 -- private extension declaration), to distinguish a partial view
14342 -- from a derivation from a private type which also appears as
14343 -- E_Private_Type. If the parent base type is not declared in an
14344 -- enclosing scope there is no need to check.
14346 elsif Present (Full_View (Parent_Type))
14347 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
14348 and then not Is_Tagged_Type (Parent_Type)
14349 and then Is_Tagged_Type (Full_View (Parent_Type))
14350 and then In_Open_Scopes (Scope (Base_Type (Parent_Type)))
14353 ("premature derivation from type with tagged full view",
14358 -- Check that form of derivation is appropriate
14360 Taggd := Is_Tagged_Type (Parent_Type);
14362 -- Perhaps the parent type should be changed to the class-wide type's
14363 -- specific type in this case to prevent cascading errors ???
14365 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
14366 Error_Msg_N ("parent type must not be a class-wide type", Indic);
14370 if Present (Extension) and then not Taggd then
14372 ("type derived from untagged type cannot have extension", Indic);
14374 elsif No (Extension) and then Taggd then
14376 -- If this declaration is within a private part (or body) of a
14377 -- generic instantiation then the derivation is allowed (the parent
14378 -- type can only appear tagged in this case if it's a generic actual
14379 -- type, since it would otherwise have been rejected in the analysis
14380 -- of the generic template).
14382 if not Is_Generic_Actual_Type (Parent_Type)
14383 or else In_Visible_Part (Scope (Parent_Type))
14385 if Is_Class_Wide_Type (Parent_Type) then
14387 ("parent type must not be a class-wide type", Indic);
14389 -- Use specific type to prevent cascaded errors.
14391 Parent_Type := Etype (Parent_Type);
14395 ("type derived from tagged type must have extension", Indic);
14400 -- AI-443: Synchronized formal derived types require a private
14401 -- extension. There is no point in checking the ancestor type or
14402 -- the progenitors since the construct is wrong to begin with.
14404 if Ada_Version >= Ada_2005
14405 and then Is_Generic_Type (T)
14406 and then Present (Original_Node (N))
14409 Decl : constant Node_Id := Original_Node (N);
14412 if Nkind (Decl) = N_Formal_Type_Declaration
14413 and then Nkind (Formal_Type_Definition (Decl)) =
14414 N_Formal_Derived_Type_Definition
14415 and then Synchronized_Present (Formal_Type_Definition (Decl))
14416 and then No (Extension)
14418 -- Avoid emitting a duplicate error message
14420 and then not Error_Posted (Indic)
14423 ("synchronized derived type must have extension", N);
14428 if Null_Exclusion_Present (Def)
14429 and then not Is_Access_Type (Parent_Type)
14431 Error_Msg_N ("null exclusion can only apply to an access type", N);
14434 -- Avoid deriving parent primitives of underlying record views
14436 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
14437 Derive_Subps => not Is_Underlying_Record_View (T));
14439 -- AI-419: The parent type of an explicitly limited derived type must
14440 -- be a limited type or a limited interface.
14442 if Limited_Present (Def) then
14443 Set_Is_Limited_Record (T);
14445 if Is_Interface (T) then
14446 Set_Is_Limited_Interface (T);
14449 if not Is_Limited_Type (Parent_Type)
14451 (not Is_Interface (Parent_Type)
14452 or else not Is_Limited_Interface (Parent_Type))
14454 -- AI05-0096: a derivation in the private part of an instance is
14455 -- legal if the generic formal is untagged limited, and the actual
14458 if Is_Generic_Actual_Type (Parent_Type)
14459 and then In_Private_Part (Current_Scope)
14462 (Generic_Parent_Type (Parent (Parent_Type)))
14468 ("parent type& of limited type must be limited",
14474 -- In SPARK, there are no derived type definitions other than type
14475 -- extensions of tagged record types.
14477 if No (Extension) then
14478 Check_SPARK_Restriction ("derived type is not allowed", N);
14480 end Derived_Type_Declaration;
14482 ------------------------
14483 -- Diagnose_Interface --
14484 ------------------------
14486 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
14488 if not Is_Interface (E)
14489 and then E /= Any_Type
14491 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
14493 end Diagnose_Interface;
14495 ----------------------------------
14496 -- Enumeration_Type_Declaration --
14497 ----------------------------------
14499 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
14506 -- Create identifier node representing lower bound
14508 B_Node := New_Node (N_Identifier, Sloc (Def));
14509 L := First (Literals (Def));
14510 Set_Chars (B_Node, Chars (L));
14511 Set_Entity (B_Node, L);
14512 Set_Etype (B_Node, T);
14513 Set_Is_Static_Expression (B_Node, True);
14515 R_Node := New_Node (N_Range, Sloc (Def));
14516 Set_Low_Bound (R_Node, B_Node);
14518 Set_Ekind (T, E_Enumeration_Type);
14519 Set_First_Literal (T, L);
14521 Set_Is_Constrained (T);
14525 -- Loop through literals of enumeration type setting pos and rep values
14526 -- except that if the Ekind is already set, then it means the literal
14527 -- was already constructed (case of a derived type declaration and we
14528 -- should not disturb the Pos and Rep values.
14530 while Present (L) loop
14531 if Ekind (L) /= E_Enumeration_Literal then
14532 Set_Ekind (L, E_Enumeration_Literal);
14533 Set_Enumeration_Pos (L, Ev);
14534 Set_Enumeration_Rep (L, Ev);
14535 Set_Is_Known_Valid (L, True);
14539 New_Overloaded_Entity (L);
14540 Generate_Definition (L);
14541 Set_Convention (L, Convention_Intrinsic);
14543 -- Case of character literal
14545 if Nkind (L) = N_Defining_Character_Literal then
14546 Set_Is_Character_Type (T, True);
14548 -- Check violation of No_Wide_Characters
14550 if Restriction_Check_Required (No_Wide_Characters) then
14551 Get_Name_String (Chars (L));
14553 if Name_Len >= 3 and then Name_Buffer (1 .. 2) = "QW" then
14554 Check_Restriction (No_Wide_Characters, L);
14563 -- Now create a node representing upper bound
14565 B_Node := New_Node (N_Identifier, Sloc (Def));
14566 Set_Chars (B_Node, Chars (Last (Literals (Def))));
14567 Set_Entity (B_Node, Last (Literals (Def)));
14568 Set_Etype (B_Node, T);
14569 Set_Is_Static_Expression (B_Node, True);
14571 Set_High_Bound (R_Node, B_Node);
14573 -- Initialize various fields of the type. Some of this information
14574 -- may be overwritten later through rep.clauses.
14576 Set_Scalar_Range (T, R_Node);
14577 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
14578 Set_Enum_Esize (T);
14579 Set_Enum_Pos_To_Rep (T, Empty);
14581 -- Enumeration type is in ALFA only if it is not a character type
14583 if not Is_Character_Type (T) then
14584 Set_Is_In_ALFA (T);
14587 -- Set Discard_Names if configuration pragma set, or if there is
14588 -- a parameterless pragma in the current declarative region
14590 if Global_Discard_Names
14591 or else Discard_Names (Scope (T))
14593 Set_Discard_Names (T);
14596 -- Process end label if there is one
14598 if Present (Def) then
14599 Process_End_Label (Def, 'e', T);
14601 end Enumeration_Type_Declaration;
14603 ---------------------------------
14604 -- Expand_To_Stored_Constraint --
14605 ---------------------------------
14607 function Expand_To_Stored_Constraint
14609 Constraint : Elist_Id) return Elist_Id
14611 Explicitly_Discriminated_Type : Entity_Id;
14612 Expansion : Elist_Id;
14613 Discriminant : Entity_Id;
14615 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
14616 -- Find the nearest type that actually specifies discriminants
14618 ---------------------------------
14619 -- Type_With_Explicit_Discrims --
14620 ---------------------------------
14622 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
14623 Typ : constant E := Base_Type (Id);
14626 if Ekind (Typ) in Incomplete_Or_Private_Kind then
14627 if Present (Full_View (Typ)) then
14628 return Type_With_Explicit_Discrims (Full_View (Typ));
14632 if Has_Discriminants (Typ) then
14637 if Etype (Typ) = Typ then
14639 elsif Has_Discriminants (Typ) then
14642 return Type_With_Explicit_Discrims (Etype (Typ));
14645 end Type_With_Explicit_Discrims;
14647 -- Start of processing for Expand_To_Stored_Constraint
14651 or else Is_Empty_Elmt_List (Constraint)
14656 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
14658 if No (Explicitly_Discriminated_Type) then
14662 Expansion := New_Elmt_List;
14665 First_Stored_Discriminant (Explicitly_Discriminated_Type);
14666 while Present (Discriminant) loop
14668 Get_Discriminant_Value (
14669 Discriminant, Explicitly_Discriminated_Type, Constraint),
14671 Next_Stored_Discriminant (Discriminant);
14675 end Expand_To_Stored_Constraint;
14677 ---------------------------
14678 -- Find_Hidden_Interface --
14679 ---------------------------
14681 function Find_Hidden_Interface
14683 Dest : Elist_Id) return Entity_Id
14686 Iface_Elmt : Elmt_Id;
14689 if Present (Src) and then Present (Dest) then
14690 Iface_Elmt := First_Elmt (Src);
14691 while Present (Iface_Elmt) loop
14692 Iface := Node (Iface_Elmt);
14694 if Is_Interface (Iface)
14695 and then not Contain_Interface (Iface, Dest)
14700 Next_Elmt (Iface_Elmt);
14705 end Find_Hidden_Interface;
14707 --------------------
14708 -- Find_Type_Name --
14709 --------------------
14711 function Find_Type_Name (N : Node_Id) return Entity_Id is
14712 Id : constant Entity_Id := Defining_Identifier (N);
14714 New_Id : Entity_Id;
14715 Prev_Par : Node_Id;
14717 procedure Tag_Mismatch;
14718 -- Diagnose a tagged partial view whose full view is untagged.
14719 -- We post the message on the full view, with a reference to
14720 -- the previous partial view. The partial view can be private
14721 -- or incomplete, and these are handled in a different manner,
14722 -- so we determine the position of the error message from the
14723 -- respective slocs of both.
14729 procedure Tag_Mismatch is
14731 if Sloc (Prev) < Sloc (Id) then
14732 if Ada_Version >= Ada_2012
14733 and then Nkind (N) = N_Private_Type_Declaration
14736 ("declaration of private } must be a tagged type ", Id, Prev);
14739 ("full declaration of } must be a tagged type ", Id, Prev);
14742 if Ada_Version >= Ada_2012
14743 and then Nkind (N) = N_Private_Type_Declaration
14746 ("declaration of private } must be a tagged type ", Prev, Id);
14749 ("full declaration of } must be a tagged type ", Prev, Id);
14754 -- Start of processing for Find_Type_Name
14757 -- Find incomplete declaration, if one was given
14759 Prev := Current_Entity_In_Scope (Id);
14761 -- New type declaration
14767 -- Previous declaration exists
14770 Prev_Par := Parent (Prev);
14772 -- Error if not incomplete/private case except if previous
14773 -- declaration is implicit, etc. Enter_Name will emit error if
14776 if not Is_Incomplete_Or_Private_Type (Prev) then
14780 -- Check invalid completion of private or incomplete type
14782 elsif not Nkind_In (N, N_Full_Type_Declaration,
14783 N_Task_Type_Declaration,
14784 N_Protected_Type_Declaration)
14786 (Ada_Version < Ada_2012
14787 or else not Is_Incomplete_Type (Prev)
14788 or else not Nkind_In (N, N_Private_Type_Declaration,
14789 N_Private_Extension_Declaration))
14791 -- Completion must be a full type declarations (RM 7.3(4))
14793 Error_Msg_Sloc := Sloc (Prev);
14794 Error_Msg_NE ("invalid completion of }", Id, Prev);
14796 -- Set scope of Id to avoid cascaded errors. Entity is never
14797 -- examined again, except when saving globals in generics.
14799 Set_Scope (Id, Current_Scope);
14802 -- If this is a repeated incomplete declaration, no further
14803 -- checks are possible.
14805 if Nkind (N) = N_Incomplete_Type_Declaration then
14809 -- Case of full declaration of incomplete type
14811 elsif Ekind (Prev) = E_Incomplete_Type
14812 and then (Ada_Version < Ada_2012
14813 or else No (Full_View (Prev))
14814 or else not Is_Private_Type (Full_View (Prev)))
14817 -- Indicate that the incomplete declaration has a matching full
14818 -- declaration. The defining occurrence of the incomplete
14819 -- declaration remains the visible one, and the procedure
14820 -- Get_Full_View dereferences it whenever the type is used.
14822 if Present (Full_View (Prev)) then
14823 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
14826 Set_Full_View (Prev, Id);
14827 Append_Entity (Id, Current_Scope);
14828 Set_Is_Public (Id, Is_Public (Prev));
14829 Set_Is_Internal (Id);
14832 -- If the incomplete view is tagged, a class_wide type has been
14833 -- created already. Use it for the private type as well, in order
14834 -- to prevent multiple incompatible class-wide types that may be
14835 -- created for self-referential anonymous access components.
14837 if Is_Tagged_Type (Prev)
14838 and then Present (Class_Wide_Type (Prev))
14840 Set_Ekind (Id, Ekind (Prev)); -- will be reset later
14841 Set_Class_Wide_Type (Id, Class_Wide_Type (Prev));
14842 Set_Etype (Class_Wide_Type (Id), Id);
14845 -- Case of full declaration of private type
14848 -- If the private type was a completion of an incomplete type then
14849 -- update Prev to reference the private type
14851 if Ada_Version >= Ada_2012
14852 and then Ekind (Prev) = E_Incomplete_Type
14853 and then Present (Full_View (Prev))
14854 and then Is_Private_Type (Full_View (Prev))
14856 Prev := Full_View (Prev);
14857 Prev_Par := Parent (Prev);
14860 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
14861 if Etype (Prev) /= Prev then
14863 -- Prev is a private subtype or a derived type, and needs
14866 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
14869 elsif Ekind (Prev) = E_Private_Type
14870 and then Nkind_In (N, N_Task_Type_Declaration,
14871 N_Protected_Type_Declaration)
14874 ("completion of nonlimited type cannot be limited", N);
14876 elsif Ekind (Prev) = E_Record_Type_With_Private
14877 and then Nkind_In (N, N_Task_Type_Declaration,
14878 N_Protected_Type_Declaration)
14880 if not Is_Limited_Record (Prev) then
14882 ("completion of nonlimited type cannot be limited", N);
14884 elsif No (Interface_List (N)) then
14886 ("completion of tagged private type must be tagged",
14890 elsif Nkind (N) = N_Full_Type_Declaration
14892 Nkind (Type_Definition (N)) = N_Record_Definition
14893 and then Interface_Present (Type_Definition (N))
14896 ("completion of private type cannot be an interface", N);
14899 -- Ada 2005 (AI-251): Private extension declaration of a task
14900 -- type or a protected type. This case arises when covering
14901 -- interface types.
14903 elsif Nkind_In (N, N_Task_Type_Declaration,
14904 N_Protected_Type_Declaration)
14908 elsif Nkind (N) /= N_Full_Type_Declaration
14909 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
14912 ("full view of private extension must be an extension", N);
14914 elsif not (Abstract_Present (Parent (Prev)))
14915 and then Abstract_Present (Type_Definition (N))
14918 ("full view of non-abstract extension cannot be abstract", N);
14921 if not In_Private_Part (Current_Scope) then
14923 ("declaration of full view must appear in private part", N);
14926 Copy_And_Swap (Prev, Id);
14927 Set_Has_Private_Declaration (Prev);
14928 Set_Has_Private_Declaration (Id);
14930 -- If no error, propagate freeze_node from private to full view.
14931 -- It may have been generated for an early operational item.
14933 if Present (Freeze_Node (Id))
14934 and then Serious_Errors_Detected = 0
14935 and then No (Full_View (Id))
14937 Set_Freeze_Node (Prev, Freeze_Node (Id));
14938 Set_Freeze_Node (Id, Empty);
14939 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
14942 Set_Full_View (Id, Prev);
14946 -- Verify that full declaration conforms to partial one
14948 if Is_Incomplete_Or_Private_Type (Prev)
14949 and then Present (Discriminant_Specifications (Prev_Par))
14951 if Present (Discriminant_Specifications (N)) then
14952 if Ekind (Prev) = E_Incomplete_Type then
14953 Check_Discriminant_Conformance (N, Prev, Prev);
14955 Check_Discriminant_Conformance (N, Prev, Id);
14960 ("missing discriminants in full type declaration", N);
14962 -- To avoid cascaded errors on subsequent use, share the
14963 -- discriminants of the partial view.
14965 Set_Discriminant_Specifications (N,
14966 Discriminant_Specifications (Prev_Par));
14970 -- A prior untagged partial view can have an associated class-wide
14971 -- type due to use of the class attribute, and in this case the full
14972 -- type must also be tagged. This Ada 95 usage is deprecated in favor
14973 -- of incomplete tagged declarations, but we check for it.
14976 and then (Is_Tagged_Type (Prev)
14977 or else Present (Class_Wide_Type (Prev)))
14979 -- Ada 2012 (AI05-0162): A private type may be the completion of
14980 -- an incomplete type
14982 if Ada_Version >= Ada_2012
14983 and then Is_Incomplete_Type (Prev)
14984 and then Nkind_In (N, N_Private_Type_Declaration,
14985 N_Private_Extension_Declaration)
14987 -- No need to check private extensions since they are tagged
14989 if Nkind (N) = N_Private_Type_Declaration
14990 and then not Tagged_Present (N)
14995 -- The full declaration is either a tagged type (including
14996 -- a synchronized type that implements interfaces) or a
14997 -- type extension, otherwise this is an error.
14999 elsif Nkind_In (N, N_Task_Type_Declaration,
15000 N_Protected_Type_Declaration)
15002 if No (Interface_List (N))
15003 and then not Error_Posted (N)
15008 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
15010 -- Indicate that the previous declaration (tagged incomplete
15011 -- or private declaration) requires the same on the full one.
15013 if not Tagged_Present (Type_Definition (N)) then
15015 Set_Is_Tagged_Type (Id);
15018 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
15019 if No (Record_Extension_Part (Type_Definition (N))) then
15021 ("full declaration of } must be a record extension",
15024 -- Set some attributes to produce a usable full view
15026 Set_Is_Tagged_Type (Id);
15036 end Find_Type_Name;
15038 -------------------------
15039 -- Find_Type_Of_Object --
15040 -------------------------
15042 function Find_Type_Of_Object
15043 (Obj_Def : Node_Id;
15044 Related_Nod : Node_Id) return Entity_Id
15046 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
15047 P : Node_Id := Parent (Obj_Def);
15052 -- If the parent is a component_definition node we climb to the
15053 -- component_declaration node
15055 if Nkind (P) = N_Component_Definition then
15059 -- Case of an anonymous array subtype
15061 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
15062 N_Unconstrained_Array_Definition)
15065 Array_Type_Declaration (T, Obj_Def);
15067 -- Create an explicit subtype whenever possible
15069 elsif Nkind (P) /= N_Component_Declaration
15070 and then Def_Kind = N_Subtype_Indication
15072 -- Base name of subtype on object name, which will be unique in
15073 -- the current scope.
15075 -- If this is a duplicate declaration, return base type, to avoid
15076 -- generating duplicate anonymous types.
15078 if Error_Posted (P) then
15079 Analyze (Subtype_Mark (Obj_Def));
15080 return Entity (Subtype_Mark (Obj_Def));
15085 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
15087 T := Make_Defining_Identifier (Sloc (P), Nam);
15089 Insert_Action (Obj_Def,
15090 Make_Subtype_Declaration (Sloc (P),
15091 Defining_Identifier => T,
15092 Subtype_Indication => Relocate_Node (Obj_Def)));
15094 -- This subtype may need freezing, and this will not be done
15095 -- automatically if the object declaration is not in declarative
15096 -- part. Since this is an object declaration, the type cannot always
15097 -- be frozen here. Deferred constants do not freeze their type
15098 -- (which often enough will be private).
15100 if Nkind (P) = N_Object_Declaration
15101 and then Constant_Present (P)
15102 and then No (Expression (P))
15106 Insert_Actions (Obj_Def, Freeze_Entity (T, P));
15109 -- Ada 2005 AI-406: the object definition in an object declaration
15110 -- can be an access definition.
15112 elsif Def_Kind = N_Access_Definition then
15113 T := Access_Definition (Related_Nod, Obj_Def);
15114 Set_Is_Local_Anonymous_Access (T);
15116 -- Otherwise, the object definition is just a subtype_mark
15119 T := Process_Subtype (Obj_Def, Related_Nod);
15121 -- If expansion is disabled an object definition that is an aggregate
15122 -- will not get expanded and may lead to scoping problems in the back
15123 -- end, if the object is referenced in an inner scope. In that case
15124 -- create an itype reference for the object definition now. This
15125 -- may be redundant in some cases, but harmless.
15128 and then Nkind (Related_Nod) = N_Object_Declaration
15131 Build_Itype_Reference (T, Related_Nod);
15136 end Find_Type_Of_Object;
15138 --------------------------------
15139 -- Find_Type_Of_Subtype_Indic --
15140 --------------------------------
15142 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
15146 -- Case of subtype mark with a constraint
15148 if Nkind (S) = N_Subtype_Indication then
15149 Find_Type (Subtype_Mark (S));
15150 Typ := Entity (Subtype_Mark (S));
15153 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
15156 ("incorrect constraint for this kind of type", Constraint (S));
15157 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
15160 -- Otherwise we have a subtype mark without a constraint
15162 elsif Error_Posted (S) then
15163 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
15171 -- Check No_Wide_Characters restriction
15173 Check_Wide_Character_Restriction (Typ, S);
15176 end Find_Type_Of_Subtype_Indic;
15178 -------------------------------------
15179 -- Floating_Point_Type_Declaration --
15180 -------------------------------------
15182 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
15183 Digs : constant Node_Id := Digits_Expression (Def);
15184 Max_Digs_Val : constant Uint := Digits_Value (Standard_Long_Long_Float);
15186 Base_Typ : Entity_Id;
15187 Implicit_Base : Entity_Id;
15190 function Can_Derive_From (E : Entity_Id) return Boolean;
15191 -- Find if given digits value, and possibly a specified range, allows
15192 -- derivation from specified type
15194 function Find_Base_Type return Entity_Id;
15195 -- Find a predefined base type that Def can derive from, or generate
15196 -- an error and substitute Long_Long_Float if none exists.
15198 ---------------------
15199 -- Can_Derive_From --
15200 ---------------------
15202 function Can_Derive_From (E : Entity_Id) return Boolean is
15203 Spec : constant Entity_Id := Real_Range_Specification (Def);
15206 if Digs_Val > Digits_Value (E) then
15210 if Present (Spec) then
15211 if Expr_Value_R (Type_Low_Bound (E)) >
15212 Expr_Value_R (Low_Bound (Spec))
15217 if Expr_Value_R (Type_High_Bound (E)) <
15218 Expr_Value_R (High_Bound (Spec))
15225 end Can_Derive_From;
15227 --------------------
15228 -- Find_Base_Type --
15229 --------------------
15231 function Find_Base_Type return Entity_Id is
15232 Choice : Elmt_Id := First_Elmt (Predefined_Float_Types);
15235 -- Iterate over the predefined types in order, returning the first
15236 -- one that Def can derive from.
15238 while Present (Choice) loop
15239 if Can_Derive_From (Node (Choice)) then
15240 return Node (Choice);
15243 Next_Elmt (Choice);
15246 -- If we can't derive from any existing type, use Long_Long_Float
15247 -- and give appropriate message explaining the problem.
15249 if Digs_Val > Max_Digs_Val then
15250 -- It might be the case that there is a type with the requested
15251 -- range, just not the combination of digits and range.
15254 ("no predefined type has requested range and precision",
15255 Real_Range_Specification (Def));
15259 ("range too large for any predefined type",
15260 Real_Range_Specification (Def));
15263 return Standard_Long_Long_Float;
15264 end Find_Base_Type;
15266 -- Start of processing for Floating_Point_Type_Declaration
15269 Check_Restriction (No_Floating_Point, Def);
15271 -- Create an implicit base type
15274 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
15276 -- Analyze and verify digits value
15278 Analyze_And_Resolve (Digs, Any_Integer);
15279 Check_Digits_Expression (Digs);
15280 Digs_Val := Expr_Value (Digs);
15282 -- Process possible range spec and find correct type to derive from
15284 Process_Real_Range_Specification (Def);
15286 -- Check that requested number of digits is not too high.
15288 if Digs_Val > Max_Digs_Val then
15289 -- The check for Max_Base_Digits may be somewhat expensive, as it
15290 -- requires reading System, so only do it when necessary.
15293 Max_Base_Digits : constant Uint :=
15296 (Parent (RTE (RE_Max_Base_Digits))));
15299 if Digs_Val > Max_Base_Digits then
15300 Error_Msg_Uint_1 := Max_Base_Digits;
15301 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
15303 elsif No (Real_Range_Specification (Def)) then
15304 Error_Msg_Uint_1 := Max_Digs_Val;
15305 Error_Msg_N ("types with more than ^ digits need range spec "
15306 & "('R'M 3.5.7(6))", Digs);
15311 -- Find a suitable type to derive from or complain and use a substitute
15313 Base_Typ := Find_Base_Type;
15315 -- If there are bounds given in the declaration use them as the bounds
15316 -- of the type, otherwise use the bounds of the predefined base type
15317 -- that was chosen based on the Digits value.
15319 if Present (Real_Range_Specification (Def)) then
15320 Set_Scalar_Range (T, Real_Range_Specification (Def));
15321 Set_Is_Constrained (T);
15323 -- The bounds of this range must be converted to machine numbers
15324 -- in accordance with RM 4.9(38).
15326 Bound := Type_Low_Bound (T);
15328 if Nkind (Bound) = N_Real_Literal then
15330 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
15331 Set_Is_Machine_Number (Bound);
15334 Bound := Type_High_Bound (T);
15336 if Nkind (Bound) = N_Real_Literal then
15338 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
15339 Set_Is_Machine_Number (Bound);
15343 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
15346 -- Complete definition of implicit base and declared first subtype
15348 Set_Etype (Implicit_Base, Base_Typ);
15350 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
15351 Set_Size_Info (Implicit_Base, (Base_Typ));
15352 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
15353 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
15354 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
15355 Set_Float_Rep (Implicit_Base, Float_Rep (Base_Typ));
15357 Set_Ekind (T, E_Floating_Point_Subtype);
15358 Set_Etype (T, Implicit_Base);
15360 Set_Size_Info (T, (Implicit_Base));
15361 Set_RM_Size (T, RM_Size (Implicit_Base));
15362 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
15363 Set_Digits_Value (T, Digs_Val);
15364 end Floating_Point_Type_Declaration;
15366 ----------------------------
15367 -- Get_Discriminant_Value --
15368 ----------------------------
15370 -- This is the situation:
15372 -- There is a non-derived type
15374 -- type T0 (Dx, Dy, Dz...)
15376 -- There are zero or more levels of derivation, with each derivation
15377 -- either purely inheriting the discriminants, or defining its own.
15379 -- type Ti is new Ti-1
15381 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
15383 -- subtype Ti is ...
15385 -- The subtype issue is avoided by the use of Original_Record_Component,
15386 -- and the fact that derived subtypes also derive the constraints.
15388 -- This chain leads back from
15390 -- Typ_For_Constraint
15392 -- Typ_For_Constraint has discriminants, and the value for each
15393 -- discriminant is given by its corresponding Elmt of Constraints.
15395 -- Discriminant is some discriminant in this hierarchy
15397 -- We need to return its value
15399 -- We do this by recursively searching each level, and looking for
15400 -- Discriminant. Once we get to the bottom, we start backing up
15401 -- returning the value for it which may in turn be a discriminant
15402 -- further up, so on the backup we continue the substitution.
15404 function Get_Discriminant_Value
15405 (Discriminant : Entity_Id;
15406 Typ_For_Constraint : Entity_Id;
15407 Constraint : Elist_Id) return Node_Id
15409 function Search_Derivation_Levels
15411 Discrim_Values : Elist_Id;
15412 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
15413 -- This is the routine that performs the recursive search of levels
15414 -- as described above.
15416 ------------------------------
15417 -- Search_Derivation_Levels --
15418 ------------------------------
15420 function Search_Derivation_Levels
15422 Discrim_Values : Elist_Id;
15423 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
15427 Result : Node_Or_Entity_Id;
15428 Result_Entity : Node_Id;
15431 -- If inappropriate type, return Error, this happens only in
15432 -- cascaded error situations, and we want to avoid a blow up.
15434 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
15438 -- Look deeper if possible. Use Stored_Constraints only for
15439 -- untagged types. For tagged types use the given constraint.
15440 -- This asymmetry needs explanation???
15442 if not Stored_Discrim_Values
15443 and then Present (Stored_Constraint (Ti))
15444 and then not Is_Tagged_Type (Ti)
15447 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
15450 Td : constant Entity_Id := Etype (Ti);
15454 Result := Discriminant;
15457 if Present (Stored_Constraint (Ti)) then
15459 Search_Derivation_Levels
15460 (Td, Stored_Constraint (Ti), True);
15463 Search_Derivation_Levels
15464 (Td, Discrim_Values, Stored_Discrim_Values);
15470 -- Extra underlying places to search, if not found above. For
15471 -- concurrent types, the relevant discriminant appears in the
15472 -- corresponding record. For a type derived from a private type
15473 -- without discriminant, the full view inherits the discriminants
15474 -- of the full view of the parent.
15476 if Result = Discriminant then
15477 if Is_Concurrent_Type (Ti)
15478 and then Present (Corresponding_Record_Type (Ti))
15481 Search_Derivation_Levels (
15482 Corresponding_Record_Type (Ti),
15484 Stored_Discrim_Values);
15486 elsif Is_Private_Type (Ti)
15487 and then not Has_Discriminants (Ti)
15488 and then Present (Full_View (Ti))
15489 and then Etype (Full_View (Ti)) /= Ti
15492 Search_Derivation_Levels (
15495 Stored_Discrim_Values);
15499 -- If Result is not a (reference to a) discriminant, return it,
15500 -- otherwise set Result_Entity to the discriminant.
15502 if Nkind (Result) = N_Defining_Identifier then
15503 pragma Assert (Result = Discriminant);
15504 Result_Entity := Result;
15507 if not Denotes_Discriminant (Result) then
15511 Result_Entity := Entity (Result);
15514 -- See if this level of derivation actually has discriminants
15515 -- because tagged derivations can add them, hence the lower
15516 -- levels need not have any.
15518 if not Has_Discriminants (Ti) then
15522 -- Scan Ti's discriminants for Result_Entity,
15523 -- and return its corresponding value, if any.
15525 Result_Entity := Original_Record_Component (Result_Entity);
15527 Assoc := First_Elmt (Discrim_Values);
15529 if Stored_Discrim_Values then
15530 Disc := First_Stored_Discriminant (Ti);
15532 Disc := First_Discriminant (Ti);
15535 while Present (Disc) loop
15536 pragma Assert (Present (Assoc));
15538 if Original_Record_Component (Disc) = Result_Entity then
15539 return Node (Assoc);
15544 if Stored_Discrim_Values then
15545 Next_Stored_Discriminant (Disc);
15547 Next_Discriminant (Disc);
15551 -- Could not find it
15554 end Search_Derivation_Levels;
15558 Result : Node_Or_Entity_Id;
15560 -- Start of processing for Get_Discriminant_Value
15563 -- ??? This routine is a gigantic mess and will be deleted. For the
15564 -- time being just test for the trivial case before calling recurse.
15566 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
15572 D := First_Discriminant (Typ_For_Constraint);
15573 E := First_Elmt (Constraint);
15574 while Present (D) loop
15575 if Chars (D) = Chars (Discriminant) then
15579 Next_Discriminant (D);
15585 Result := Search_Derivation_Levels
15586 (Typ_For_Constraint, Constraint, False);
15588 -- ??? hack to disappear when this routine is gone
15590 if Nkind (Result) = N_Defining_Identifier then
15596 D := First_Discriminant (Typ_For_Constraint);
15597 E := First_Elmt (Constraint);
15598 while Present (D) loop
15599 if Corresponding_Discriminant (D) = Discriminant then
15603 Next_Discriminant (D);
15609 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
15611 end Get_Discriminant_Value;
15613 --------------------------
15614 -- Has_Range_Constraint --
15615 --------------------------
15617 function Has_Range_Constraint (N : Node_Id) return Boolean is
15618 C : constant Node_Id := Constraint (N);
15621 if Nkind (C) = N_Range_Constraint then
15624 elsif Nkind (C) = N_Digits_Constraint then
15626 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
15628 Present (Range_Constraint (C));
15630 elsif Nkind (C) = N_Delta_Constraint then
15631 return Present (Range_Constraint (C));
15636 end Has_Range_Constraint;
15638 ------------------------
15639 -- Inherit_Components --
15640 ------------------------
15642 function Inherit_Components
15644 Parent_Base : Entity_Id;
15645 Derived_Base : Entity_Id;
15646 Is_Tagged : Boolean;
15647 Inherit_Discr : Boolean;
15648 Discs : Elist_Id) return Elist_Id
15650 Assoc_List : constant Elist_Id := New_Elmt_List;
15652 procedure Inherit_Component
15653 (Old_C : Entity_Id;
15654 Plain_Discrim : Boolean := False;
15655 Stored_Discrim : Boolean := False);
15656 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
15657 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
15658 -- True, Old_C is a stored discriminant. If they are both false then
15659 -- Old_C is a regular component.
15661 -----------------------
15662 -- Inherit_Component --
15663 -----------------------
15665 procedure Inherit_Component
15666 (Old_C : Entity_Id;
15667 Plain_Discrim : Boolean := False;
15668 Stored_Discrim : Boolean := False)
15670 New_C : constant Entity_Id := New_Copy (Old_C);
15672 Discrim : Entity_Id;
15673 Corr_Discrim : Entity_Id;
15676 pragma Assert (not Is_Tagged or else not Stored_Discrim);
15678 Set_Parent (New_C, Parent (Old_C));
15680 -- Regular discriminants and components must be inserted in the scope
15681 -- of the Derived_Base. Do it here.
15683 if not Stored_Discrim then
15684 Enter_Name (New_C);
15687 -- For tagged types the Original_Record_Component must point to
15688 -- whatever this field was pointing to in the parent type. This has
15689 -- already been achieved by the call to New_Copy above.
15691 if not Is_Tagged then
15692 Set_Original_Record_Component (New_C, New_C);
15695 -- If we have inherited a component then see if its Etype contains
15696 -- references to Parent_Base discriminants. In this case, replace
15697 -- these references with the constraints given in Discs. We do not
15698 -- do this for the partial view of private types because this is
15699 -- not needed (only the components of the full view will be used
15700 -- for code generation) and cause problem. We also avoid this
15701 -- transformation in some error situations.
15703 if Ekind (New_C) = E_Component then
15704 if (Is_Private_Type (Derived_Base)
15705 and then not Is_Generic_Type (Derived_Base))
15706 or else (Is_Empty_Elmt_List (Discs)
15707 and then not Expander_Active)
15709 Set_Etype (New_C, Etype (Old_C));
15712 -- The current component introduces a circularity of the
15715 -- limited with Pack_2;
15716 -- package Pack_1 is
15717 -- type T_1 is tagged record
15718 -- Comp : access Pack_2.T_2;
15724 -- package Pack_2 is
15725 -- type T_2 is new Pack_1.T_1 with ...;
15730 Constrain_Component_Type
15731 (Old_C, Derived_Base, N, Parent_Base, Discs));
15735 -- In derived tagged types it is illegal to reference a non
15736 -- discriminant component in the parent type. To catch this, mark
15737 -- these components with an Ekind of E_Void. This will be reset in
15738 -- Record_Type_Definition after processing the record extension of
15739 -- the derived type.
15741 -- If the declaration is a private extension, there is no further
15742 -- record extension to process, and the components retain their
15743 -- current kind, because they are visible at this point.
15745 if Is_Tagged and then Ekind (New_C) = E_Component
15746 and then Nkind (N) /= N_Private_Extension_Declaration
15748 Set_Ekind (New_C, E_Void);
15751 if Plain_Discrim then
15752 Set_Corresponding_Discriminant (New_C, Old_C);
15753 Build_Discriminal (New_C);
15755 -- If we are explicitly inheriting a stored discriminant it will be
15756 -- completely hidden.
15758 elsif Stored_Discrim then
15759 Set_Corresponding_Discriminant (New_C, Empty);
15760 Set_Discriminal (New_C, Empty);
15761 Set_Is_Completely_Hidden (New_C);
15763 -- Set the Original_Record_Component of each discriminant in the
15764 -- derived base to point to the corresponding stored that we just
15767 Discrim := First_Discriminant (Derived_Base);
15768 while Present (Discrim) loop
15769 Corr_Discrim := Corresponding_Discriminant (Discrim);
15771 -- Corr_Discrim could be missing in an error situation
15773 if Present (Corr_Discrim)
15774 and then Original_Record_Component (Corr_Discrim) = Old_C
15776 Set_Original_Record_Component (Discrim, New_C);
15779 Next_Discriminant (Discrim);
15782 Append_Entity (New_C, Derived_Base);
15785 if not Is_Tagged then
15786 Append_Elmt (Old_C, Assoc_List);
15787 Append_Elmt (New_C, Assoc_List);
15789 end Inherit_Component;
15791 -- Variables local to Inherit_Component
15793 Loc : constant Source_Ptr := Sloc (N);
15795 Parent_Discrim : Entity_Id;
15796 Stored_Discrim : Entity_Id;
15798 Component : Entity_Id;
15800 -- Start of processing for Inherit_Components
15803 if not Is_Tagged then
15804 Append_Elmt (Parent_Base, Assoc_List);
15805 Append_Elmt (Derived_Base, Assoc_List);
15808 -- Inherit parent discriminants if needed
15810 if Inherit_Discr then
15811 Parent_Discrim := First_Discriminant (Parent_Base);
15812 while Present (Parent_Discrim) loop
15813 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
15814 Next_Discriminant (Parent_Discrim);
15818 -- Create explicit stored discrims for untagged types when necessary
15820 if not Has_Unknown_Discriminants (Derived_Base)
15821 and then Has_Discriminants (Parent_Base)
15822 and then not Is_Tagged
15825 or else First_Discriminant (Parent_Base) /=
15826 First_Stored_Discriminant (Parent_Base))
15828 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
15829 while Present (Stored_Discrim) loop
15830 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
15831 Next_Stored_Discriminant (Stored_Discrim);
15835 -- See if we can apply the second transformation for derived types, as
15836 -- explained in point 6. in the comments above Build_Derived_Record_Type
15837 -- This is achieved by appending Derived_Base discriminants into Discs,
15838 -- which has the side effect of returning a non empty Discs list to the
15839 -- caller of Inherit_Components, which is what we want. This must be
15840 -- done for private derived types if there are explicit stored
15841 -- discriminants, to ensure that we can retrieve the values of the
15842 -- constraints provided in the ancestors.
15845 and then Is_Empty_Elmt_List (Discs)
15846 and then Present (First_Discriminant (Derived_Base))
15848 (not Is_Private_Type (Derived_Base)
15849 or else Is_Completely_Hidden
15850 (First_Stored_Discriminant (Derived_Base))
15851 or else Is_Generic_Type (Derived_Base))
15853 D := First_Discriminant (Derived_Base);
15854 while Present (D) loop
15855 Append_Elmt (New_Reference_To (D, Loc), Discs);
15856 Next_Discriminant (D);
15860 -- Finally, inherit non-discriminant components unless they are not
15861 -- visible because defined or inherited from the full view of the
15862 -- parent. Don't inherit the _parent field of the parent type.
15864 Component := First_Entity (Parent_Base);
15865 while Present (Component) loop
15867 -- Ada 2005 (AI-251): Do not inherit components associated with
15868 -- secondary tags of the parent.
15870 if Ekind (Component) = E_Component
15871 and then Present (Related_Type (Component))
15875 elsif Ekind (Component) /= E_Component
15876 or else Chars (Component) = Name_uParent
15880 -- If the derived type is within the parent type's declarative
15881 -- region, then the components can still be inherited even though
15882 -- they aren't visible at this point. This can occur for cases
15883 -- such as within public child units where the components must
15884 -- become visible upon entering the child unit's private part.
15886 elsif not Is_Visible_Component (Component)
15887 and then not In_Open_Scopes (Scope (Parent_Base))
15891 elsif Ekind_In (Derived_Base, E_Private_Type,
15892 E_Limited_Private_Type)
15897 Inherit_Component (Component);
15900 Next_Entity (Component);
15903 -- For tagged derived types, inherited discriminants cannot be used in
15904 -- component declarations of the record extension part. To achieve this
15905 -- we mark the inherited discriminants as not visible.
15907 if Is_Tagged and then Inherit_Discr then
15908 D := First_Discriminant (Derived_Base);
15909 while Present (D) loop
15910 Set_Is_Immediately_Visible (D, False);
15911 Next_Discriminant (D);
15916 end Inherit_Components;
15918 -----------------------
15919 -- Is_Constant_Bound --
15920 -----------------------
15922 function Is_Constant_Bound (Exp : Node_Id) return Boolean is
15924 if Compile_Time_Known_Value (Exp) then
15927 elsif Is_Entity_Name (Exp)
15928 and then Present (Entity (Exp))
15930 return Is_Constant_Object (Entity (Exp))
15931 or else Ekind (Entity (Exp)) = E_Enumeration_Literal;
15933 elsif Nkind (Exp) in N_Binary_Op then
15934 return Is_Constant_Bound (Left_Opnd (Exp))
15935 and then Is_Constant_Bound (Right_Opnd (Exp))
15936 and then Scope (Entity (Exp)) = Standard_Standard;
15941 end Is_Constant_Bound;
15943 -----------------------
15944 -- Is_Null_Extension --
15945 -----------------------
15947 function Is_Null_Extension (T : Entity_Id) return Boolean is
15948 Type_Decl : constant Node_Id := Parent (Base_Type (T));
15949 Comp_List : Node_Id;
15953 if Nkind (Type_Decl) /= N_Full_Type_Declaration
15954 or else not Is_Tagged_Type (T)
15955 or else Nkind (Type_Definition (Type_Decl)) /=
15956 N_Derived_Type_Definition
15957 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
15963 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
15965 if Present (Discriminant_Specifications (Type_Decl)) then
15968 elsif Present (Comp_List)
15969 and then Is_Non_Empty_List (Component_Items (Comp_List))
15971 Comp := First (Component_Items (Comp_List));
15973 -- Only user-defined components are relevant. The component list
15974 -- may also contain a parent component and internal components
15975 -- corresponding to secondary tags, but these do not determine
15976 -- whether this is a null extension.
15978 while Present (Comp) loop
15979 if Comes_From_Source (Comp) then
15990 end Is_Null_Extension;
15992 ------------------------------
15993 -- Is_Valid_Constraint_Kind --
15994 ------------------------------
15996 function Is_Valid_Constraint_Kind
15997 (T_Kind : Type_Kind;
15998 Constraint_Kind : Node_Kind) return Boolean
16002 when Enumeration_Kind |
16004 return Constraint_Kind = N_Range_Constraint;
16006 when Decimal_Fixed_Point_Kind =>
16007 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
16008 N_Range_Constraint);
16010 when Ordinary_Fixed_Point_Kind =>
16011 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
16012 N_Range_Constraint);
16015 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
16016 N_Range_Constraint);
16023 E_Incomplete_Type |
16026 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
16029 return True; -- Error will be detected later
16031 end Is_Valid_Constraint_Kind;
16033 --------------------------
16034 -- Is_Visible_Component --
16035 --------------------------
16037 function Is_Visible_Component (C : Entity_Id) return Boolean is
16038 Original_Comp : Entity_Id := Empty;
16039 Original_Scope : Entity_Id;
16040 Type_Scope : Entity_Id;
16042 function Is_Local_Type (Typ : Entity_Id) return Boolean;
16043 -- Check whether parent type of inherited component is declared locally,
16044 -- possibly within a nested package or instance. The current scope is
16045 -- the derived record itself.
16047 -------------------
16048 -- Is_Local_Type --
16049 -------------------
16051 function Is_Local_Type (Typ : Entity_Id) return Boolean is
16055 Scop := Scope (Typ);
16056 while Present (Scop)
16057 and then Scop /= Standard_Standard
16059 if Scop = Scope (Current_Scope) then
16063 Scop := Scope (Scop);
16069 -- Start of processing for Is_Visible_Component
16072 if Ekind_In (C, E_Component, E_Discriminant) then
16073 Original_Comp := Original_Record_Component (C);
16076 if No (Original_Comp) then
16078 -- Premature usage, or previous error
16083 Original_Scope := Scope (Original_Comp);
16084 Type_Scope := Scope (Base_Type (Scope (C)));
16087 -- This test only concerns tagged types
16089 if not Is_Tagged_Type (Original_Scope) then
16092 -- If it is _Parent or _Tag, there is no visibility issue
16094 elsif not Comes_From_Source (Original_Comp) then
16097 -- If we are in the body of an instantiation, the component is visible
16098 -- even when the parent type (possibly defined in an enclosing unit or
16099 -- in a parent unit) might not.
16101 elsif In_Instance_Body then
16104 -- Discriminants are always visible
16106 elsif Ekind (Original_Comp) = E_Discriminant
16107 and then not Has_Unknown_Discriminants (Original_Scope)
16111 -- If the component has been declared in an ancestor which is currently
16112 -- a private type, then it is not visible. The same applies if the
16113 -- component's containing type is not in an open scope and the original
16114 -- component's enclosing type is a visible full view of a private type
16115 -- (which can occur in cases where an attempt is being made to reference
16116 -- a component in a sibling package that is inherited from a visible
16117 -- component of a type in an ancestor package; the component in the
16118 -- sibling package should not be visible even though the component it
16119 -- inherited from is visible). This does not apply however in the case
16120 -- where the scope of the type is a private child unit, or when the
16121 -- parent comes from a local package in which the ancestor is currently
16122 -- visible. The latter suppression of visibility is needed for cases
16123 -- that are tested in B730006.
16125 elsif Is_Private_Type (Original_Scope)
16127 (not Is_Private_Descendant (Type_Scope)
16128 and then not In_Open_Scopes (Type_Scope)
16129 and then Has_Private_Declaration (Original_Scope))
16131 -- If the type derives from an entity in a formal package, there
16132 -- are no additional visible components.
16134 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
16135 N_Formal_Package_Declaration
16139 -- if we are not in the private part of the current package, there
16140 -- are no additional visible components.
16142 elsif Ekind (Scope (Current_Scope)) = E_Package
16143 and then not In_Private_Part (Scope (Current_Scope))
16148 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
16149 and then In_Open_Scopes (Scope (Original_Scope))
16150 and then Is_Local_Type (Type_Scope);
16153 -- There is another weird way in which a component may be invisible
16154 -- when the private and the full view are not derived from the same
16155 -- ancestor. Here is an example :
16157 -- type A1 is tagged record F1 : integer; end record;
16158 -- type A2 is new A1 with record F2 : integer; end record;
16159 -- type T is new A1 with private;
16161 -- type T is new A2 with null record;
16163 -- In this case, the full view of T inherits F1 and F2 but the private
16164 -- view inherits only F1
16168 Ancestor : Entity_Id := Scope (C);
16172 if Ancestor = Original_Scope then
16174 elsif Ancestor = Etype (Ancestor) then
16178 Ancestor := Etype (Ancestor);
16182 end Is_Visible_Component;
16184 --------------------------
16185 -- Make_Class_Wide_Type --
16186 --------------------------
16188 procedure Make_Class_Wide_Type (T : Entity_Id) is
16189 CW_Type : Entity_Id;
16191 Next_E : Entity_Id;
16194 if Present (Class_Wide_Type (T)) then
16196 -- The class-wide type is a partially decorated entity created for a
16197 -- unanalyzed tagged type referenced through a limited with clause.
16198 -- When the tagged type is analyzed, its class-wide type needs to be
16199 -- redecorated. Note that we reuse the entity created by Decorate_
16200 -- Tagged_Type in order to preserve all links.
16202 if Materialize_Entity (Class_Wide_Type (T)) then
16203 CW_Type := Class_Wide_Type (T);
16204 Set_Materialize_Entity (CW_Type, False);
16206 -- The class wide type can have been defined by the partial view, in
16207 -- which case everything is already done.
16213 -- Default case, we need to create a new class-wide type
16217 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
16220 -- Inherit root type characteristics
16222 CW_Name := Chars (CW_Type);
16223 Next_E := Next_Entity (CW_Type);
16224 Copy_Node (T, CW_Type);
16225 Set_Comes_From_Source (CW_Type, False);
16226 Set_Chars (CW_Type, CW_Name);
16227 Set_Parent (CW_Type, Parent (T));
16228 Set_Next_Entity (CW_Type, Next_E);
16230 -- Ensure we have a new freeze node for the class-wide type. The partial
16231 -- view may have freeze action of its own, requiring a proper freeze
16232 -- node, and the same freeze node cannot be shared between the two
16235 Set_Has_Delayed_Freeze (CW_Type);
16236 Set_Freeze_Node (CW_Type, Empty);
16238 -- Customize the class-wide type: It has no prim. op., it cannot be
16239 -- abstract and its Etype points back to the specific root type.
16241 Set_Ekind (CW_Type, E_Class_Wide_Type);
16242 Set_Is_Tagged_Type (CW_Type, True);
16243 Set_Direct_Primitive_Operations (CW_Type, New_Elmt_List);
16244 Set_Is_Abstract_Type (CW_Type, False);
16245 Set_Is_Constrained (CW_Type, False);
16246 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
16248 if Ekind (T) = E_Class_Wide_Subtype then
16249 Set_Etype (CW_Type, Etype (Base_Type (T)));
16251 Set_Etype (CW_Type, T);
16254 -- If this is the class_wide type of a constrained subtype, it does
16255 -- not have discriminants.
16257 Set_Has_Discriminants (CW_Type,
16258 Has_Discriminants (T) and then not Is_Constrained (T));
16260 Set_Has_Unknown_Discriminants (CW_Type, True);
16261 Set_Class_Wide_Type (T, CW_Type);
16262 Set_Equivalent_Type (CW_Type, Empty);
16264 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
16266 Set_Class_Wide_Type (CW_Type, CW_Type);
16267 end Make_Class_Wide_Type;
16273 procedure Make_Index
16275 Related_Nod : Node_Id;
16276 Related_Id : Entity_Id := Empty;
16277 Suffix_Index : Nat := 1;
16278 In_Iter_Schm : Boolean := False)
16282 Def_Id : Entity_Id := Empty;
16283 Found : Boolean := False;
16286 -- For a discrete range used in a constrained array definition and
16287 -- defined by a range, an implicit conversion to the predefined type
16288 -- INTEGER is assumed if each bound is either a numeric literal, a named
16289 -- number, or an attribute, and the type of both bounds (prior to the
16290 -- implicit conversion) is the type universal_integer. Otherwise, both
16291 -- bounds must be of the same discrete type, other than universal
16292 -- integer; this type must be determinable independently of the
16293 -- context, but using the fact that the type must be discrete and that
16294 -- both bounds must have the same type.
16296 -- Character literals also have a universal type in the absence of
16297 -- of additional context, and are resolved to Standard_Character.
16299 if Nkind (I) = N_Range then
16301 -- The index is given by a range constraint. The bounds are known
16302 -- to be of a consistent type.
16304 if not Is_Overloaded (I) then
16307 -- For universal bounds, choose the specific predefined type
16309 if T = Universal_Integer then
16310 T := Standard_Integer;
16312 elsif T = Any_Character then
16313 Ambiguous_Character (Low_Bound (I));
16315 T := Standard_Character;
16318 -- The node may be overloaded because some user-defined operators
16319 -- are available, but if a universal interpretation exists it is
16320 -- also the selected one.
16322 elsif Universal_Interpretation (I) = Universal_Integer then
16323 T := Standard_Integer;
16329 Ind : Interp_Index;
16333 Get_First_Interp (I, Ind, It);
16334 while Present (It.Typ) loop
16335 if Is_Discrete_Type (It.Typ) then
16338 and then not Covers (It.Typ, T)
16339 and then not Covers (T, It.Typ)
16341 Error_Msg_N ("ambiguous bounds in discrete range", I);
16349 Get_Next_Interp (Ind, It);
16352 if T = Any_Type then
16353 Error_Msg_N ("discrete type required for range", I);
16354 Set_Etype (I, Any_Type);
16357 elsif T = Universal_Integer then
16358 T := Standard_Integer;
16363 if not Is_Discrete_Type (T) then
16364 Error_Msg_N ("discrete type required for range", I);
16365 Set_Etype (I, Any_Type);
16369 if Nkind (Low_Bound (I)) = N_Attribute_Reference
16370 and then Attribute_Name (Low_Bound (I)) = Name_First
16371 and then Is_Entity_Name (Prefix (Low_Bound (I)))
16372 and then Is_Type (Entity (Prefix (Low_Bound (I))))
16373 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (I))))
16375 -- The type of the index will be the type of the prefix, as long
16376 -- as the upper bound is 'Last of the same type.
16378 Def_Id := Entity (Prefix (Low_Bound (I)));
16380 if Nkind (High_Bound (I)) /= N_Attribute_Reference
16381 or else Attribute_Name (High_Bound (I)) /= Name_Last
16382 or else not Is_Entity_Name (Prefix (High_Bound (I)))
16383 or else Entity (Prefix (High_Bound (I))) /= Def_Id
16390 Process_Range_Expr_In_Decl (R, T, In_Iter_Schm => In_Iter_Schm);
16392 elsif Nkind (I) = N_Subtype_Indication then
16394 -- The index is given by a subtype with a range constraint
16396 T := Base_Type (Entity (Subtype_Mark (I)));
16398 if not Is_Discrete_Type (T) then
16399 Error_Msg_N ("discrete type required for range", I);
16400 Set_Etype (I, Any_Type);
16404 R := Range_Expression (Constraint (I));
16407 Process_Range_Expr_In_Decl
16408 (R, Entity (Subtype_Mark (I)), In_Iter_Schm => In_Iter_Schm);
16410 elsif Nkind (I) = N_Attribute_Reference then
16412 -- The parser guarantees that the attribute is a RANGE attribute
16414 -- If the node denotes the range of a type mark, that is also the
16415 -- resulting type, and we do no need to create an Itype for it.
16417 if Is_Entity_Name (Prefix (I))
16418 and then Comes_From_Source (I)
16419 and then Is_Type (Entity (Prefix (I)))
16420 and then Is_Discrete_Type (Entity (Prefix (I)))
16422 Def_Id := Entity (Prefix (I));
16425 Analyze_And_Resolve (I);
16429 -- If none of the above, must be a subtype. We convert this to a
16430 -- range attribute reference because in the case of declared first
16431 -- named subtypes, the types in the range reference can be different
16432 -- from the type of the entity. A range attribute normalizes the
16433 -- reference and obtains the correct types for the bounds.
16435 -- This transformation is in the nature of an expansion, is only
16436 -- done if expansion is active. In particular, it is not done on
16437 -- formal generic types, because we need to retain the name of the
16438 -- original index for instantiation purposes.
16441 if not Is_Entity_Name (I) or else not Is_Type (Entity (I)) then
16442 Error_Msg_N ("invalid subtype mark in discrete range ", I);
16443 Set_Etype (I, Any_Integer);
16447 -- The type mark may be that of an incomplete type. It is only
16448 -- now that we can get the full view, previous analysis does
16449 -- not look specifically for a type mark.
16451 Set_Entity (I, Get_Full_View (Entity (I)));
16452 Set_Etype (I, Entity (I));
16453 Def_Id := Entity (I);
16455 if not Is_Discrete_Type (Def_Id) then
16456 Error_Msg_N ("discrete type required for index", I);
16457 Set_Etype (I, Any_Type);
16462 if Expander_Active then
16464 Make_Attribute_Reference (Sloc (I),
16465 Attribute_Name => Name_Range,
16466 Prefix => Relocate_Node (I)));
16468 -- The original was a subtype mark that does not freeze. This
16469 -- means that the rewritten version must not freeze either.
16471 Set_Must_Not_Freeze (I);
16472 Set_Must_Not_Freeze (Prefix (I));
16474 -- Is order critical??? if so, document why, if not
16475 -- use Analyze_And_Resolve
16477 Analyze_And_Resolve (I);
16481 -- If expander is inactive, type is legal, nothing else to construct
16488 if not Is_Discrete_Type (T) then
16489 Error_Msg_N ("discrete type required for range", I);
16490 Set_Etype (I, Any_Type);
16493 elsif T = Any_Type then
16494 Set_Etype (I, Any_Type);
16498 -- We will now create the appropriate Itype to describe the range, but
16499 -- first a check. If we originally had a subtype, then we just label
16500 -- the range with this subtype. Not only is there no need to construct
16501 -- a new subtype, but it is wrong to do so for two reasons:
16503 -- 1. A legality concern, if we have a subtype, it must not freeze,
16504 -- and the Itype would cause freezing incorrectly
16506 -- 2. An efficiency concern, if we created an Itype, it would not be
16507 -- recognized as the same type for the purposes of eliminating
16508 -- checks in some circumstances.
16510 -- We signal this case by setting the subtype entity in Def_Id
16512 if No (Def_Id) then
16514 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
16515 Set_Etype (Def_Id, Base_Type (T));
16517 if Is_Signed_Integer_Type (T) then
16518 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
16520 elsif Is_Modular_Integer_Type (T) then
16521 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
16524 Set_Ekind (Def_Id, E_Enumeration_Subtype);
16525 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
16526 Set_First_Literal (Def_Id, First_Literal (T));
16529 Set_Size_Info (Def_Id, (T));
16530 Set_RM_Size (Def_Id, RM_Size (T));
16531 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
16533 Set_Scalar_Range (Def_Id, R);
16534 Conditional_Delay (Def_Id, T);
16536 -- In the subtype indication case, if the immediate parent of the
16537 -- new subtype is non-static, then the subtype we create is non-
16538 -- static, even if its bounds are static.
16540 if Nkind (I) = N_Subtype_Indication
16541 and then not Is_Static_Subtype (Entity (Subtype_Mark (I)))
16543 Set_Is_Non_Static_Subtype (Def_Id);
16547 -- Final step is to label the index with this constructed type
16549 Set_Etype (I, Def_Id);
16552 ------------------------------
16553 -- Modular_Type_Declaration --
16554 ------------------------------
16556 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
16557 Mod_Expr : constant Node_Id := Expression (Def);
16560 procedure Set_Modular_Size (Bits : Int);
16561 -- Sets RM_Size to Bits, and Esize to normal word size above this
16563 ----------------------
16564 -- Set_Modular_Size --
16565 ----------------------
16567 procedure Set_Modular_Size (Bits : Int) is
16569 Set_RM_Size (T, UI_From_Int (Bits));
16574 elsif Bits <= 16 then
16575 Init_Esize (T, 16);
16577 elsif Bits <= 32 then
16578 Init_Esize (T, 32);
16581 Init_Esize (T, System_Max_Binary_Modulus_Power);
16584 if not Non_Binary_Modulus (T)
16585 and then Esize (T) = RM_Size (T)
16587 Set_Is_Known_Valid (T);
16589 end Set_Modular_Size;
16591 -- Start of processing for Modular_Type_Declaration
16594 Analyze_And_Resolve (Mod_Expr, Any_Integer);
16596 Set_Ekind (T, E_Modular_Integer_Type);
16597 Init_Alignment (T);
16598 Set_Is_Constrained (T);
16600 if not Is_OK_Static_Expression (Mod_Expr) then
16601 Flag_Non_Static_Expr
16602 ("non-static expression used for modular type bound!", Mod_Expr);
16603 M_Val := 2 ** System_Max_Binary_Modulus_Power;
16605 M_Val := Expr_Value (Mod_Expr);
16609 Error_Msg_N ("modulus value must be positive", Mod_Expr);
16610 M_Val := 2 ** System_Max_Binary_Modulus_Power;
16613 Set_Modulus (T, M_Val);
16615 -- Create bounds for the modular type based on the modulus given in
16616 -- the type declaration and then analyze and resolve those bounds.
16618 Set_Scalar_Range (T,
16619 Make_Range (Sloc (Mod_Expr),
16620 Low_Bound => Make_Integer_Literal (Sloc (Mod_Expr), 0),
16621 High_Bound => Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
16623 -- Properly analyze the literals for the range. We do this manually
16624 -- because we can't go calling Resolve, since we are resolving these
16625 -- bounds with the type, and this type is certainly not complete yet!
16627 Set_Etype (Low_Bound (Scalar_Range (T)), T);
16628 Set_Etype (High_Bound (Scalar_Range (T)), T);
16629 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
16630 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
16632 -- Loop through powers of two to find number of bits required
16634 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
16638 if M_Val = 2 ** Bits then
16639 Set_Modular_Size (Bits);
16644 elsif M_Val < 2 ** Bits then
16645 Check_SPARK_Restriction ("modulus should be a power of 2", T);
16646 Set_Non_Binary_Modulus (T);
16648 if Bits > System_Max_Nonbinary_Modulus_Power then
16649 Error_Msg_Uint_1 :=
16650 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
16652 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
16653 Set_Modular_Size (System_Max_Binary_Modulus_Power);
16657 -- In the non-binary case, set size as per RM 13.3(55)
16659 Set_Modular_Size (Bits);
16666 -- If we fall through, then the size exceed System.Max_Binary_Modulus
16667 -- so we just signal an error and set the maximum size.
16669 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
16670 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
16672 Set_Modular_Size (System_Max_Binary_Modulus_Power);
16673 Init_Alignment (T);
16675 end Modular_Type_Declaration;
16677 --------------------------
16678 -- New_Concatenation_Op --
16679 --------------------------
16681 procedure New_Concatenation_Op (Typ : Entity_Id) is
16682 Loc : constant Source_Ptr := Sloc (Typ);
16685 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
16686 -- Create abbreviated declaration for the formal of a predefined
16687 -- Operator 'Op' of type 'Typ'
16689 --------------------
16690 -- Make_Op_Formal --
16691 --------------------
16693 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
16694 Formal : Entity_Id;
16696 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
16697 Set_Etype (Formal, Typ);
16698 Set_Mechanism (Formal, Default_Mechanism);
16700 end Make_Op_Formal;
16702 -- Start of processing for New_Concatenation_Op
16705 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
16707 Set_Ekind (Op, E_Operator);
16708 Set_Scope (Op, Current_Scope);
16709 Set_Etype (Op, Typ);
16710 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
16711 Set_Is_Immediately_Visible (Op);
16712 Set_Is_Intrinsic_Subprogram (Op);
16713 Set_Has_Completion (Op);
16714 Append_Entity (Op, Current_Scope);
16716 Set_Name_Entity_Id (Name_Op_Concat, Op);
16718 Append_Entity (Make_Op_Formal (Typ, Op), Op);
16719 Append_Entity (Make_Op_Formal (Typ, Op), Op);
16720 end New_Concatenation_Op;
16722 -------------------------
16723 -- OK_For_Limited_Init --
16724 -------------------------
16726 -- ???Check all calls of this, and compare the conditions under which it's
16729 function OK_For_Limited_Init
16731 Exp : Node_Id) return Boolean
16734 return Is_CPP_Constructor_Call (Exp)
16735 or else (Ada_Version >= Ada_2005
16736 and then not Debug_Flag_Dot_L
16737 and then OK_For_Limited_Init_In_05 (Typ, Exp));
16738 end OK_For_Limited_Init;
16740 -------------------------------
16741 -- OK_For_Limited_Init_In_05 --
16742 -------------------------------
16744 function OK_For_Limited_Init_In_05
16746 Exp : Node_Id) return Boolean
16749 -- An object of a limited interface type can be initialized with any
16750 -- expression of a nonlimited descendant type.
16752 if Is_Class_Wide_Type (Typ)
16753 and then Is_Limited_Interface (Typ)
16754 and then not Is_Limited_Type (Etype (Exp))
16759 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
16760 -- case of limited aggregates (including extension aggregates), and
16761 -- function calls. The function call may have been given in prefixed
16762 -- notation, in which case the original node is an indexed component.
16763 -- If the function is parameterless, the original node was an explicit
16766 case Nkind (Original_Node (Exp)) is
16767 when N_Aggregate | N_Extension_Aggregate | N_Function_Call | N_Op =>
16770 when N_Qualified_Expression =>
16772 OK_For_Limited_Init_In_05
16773 (Typ, Expression (Original_Node (Exp)));
16775 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
16776 -- with a function call, the expander has rewritten the call into an
16777 -- N_Type_Conversion node to force displacement of the pointer to
16778 -- reference the component containing the secondary dispatch table.
16779 -- Otherwise a type conversion is not a legal context.
16780 -- A return statement for a build-in-place function returning a
16781 -- synchronized type also introduces an unchecked conversion.
16783 when N_Type_Conversion |
16784 N_Unchecked_Type_Conversion =>
16785 return not Comes_From_Source (Exp)
16787 OK_For_Limited_Init_In_05
16788 (Typ, Expression (Original_Node (Exp)));
16790 when N_Indexed_Component |
16791 N_Selected_Component |
16792 N_Explicit_Dereference =>
16793 return Nkind (Exp) = N_Function_Call;
16795 -- A use of 'Input is a function call, hence allowed. Normally the
16796 -- attribute will be changed to a call, but the attribute by itself
16797 -- can occur with -gnatc.
16799 when N_Attribute_Reference =>
16800 return Attribute_Name (Original_Node (Exp)) = Name_Input;
16805 end OK_For_Limited_Init_In_05;
16807 -------------------------------------------
16808 -- Ordinary_Fixed_Point_Type_Declaration --
16809 -------------------------------------------
16811 procedure Ordinary_Fixed_Point_Type_Declaration
16815 Loc : constant Source_Ptr := Sloc (Def);
16816 Delta_Expr : constant Node_Id := Delta_Expression (Def);
16817 RRS : constant Node_Id := Real_Range_Specification (Def);
16818 Implicit_Base : Entity_Id;
16825 Check_Restriction (No_Fixed_Point, Def);
16827 -- Create implicit base type
16830 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
16831 Set_Etype (Implicit_Base, Implicit_Base);
16833 -- Analyze and process delta expression
16835 Analyze_And_Resolve (Delta_Expr, Any_Real);
16837 Check_Delta_Expression (Delta_Expr);
16838 Delta_Val := Expr_Value_R (Delta_Expr);
16840 Set_Delta_Value (Implicit_Base, Delta_Val);
16842 -- Compute default small from given delta, which is the largest power
16843 -- of two that does not exceed the given delta value.
16853 if Delta_Val < Ureal_1 then
16854 while Delta_Val < Tmp loop
16855 Tmp := Tmp / Ureal_2;
16856 Scale := Scale + 1;
16861 Tmp := Tmp * Ureal_2;
16862 exit when Tmp > Delta_Val;
16863 Scale := Scale - 1;
16867 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
16870 Set_Small_Value (Implicit_Base, Small_Val);
16872 -- If no range was given, set a dummy range
16874 if RRS <= Empty_Or_Error then
16875 Low_Val := -Small_Val;
16876 High_Val := Small_Val;
16878 -- Otherwise analyze and process given range
16882 Low : constant Node_Id := Low_Bound (RRS);
16883 High : constant Node_Id := High_Bound (RRS);
16886 Analyze_And_Resolve (Low, Any_Real);
16887 Analyze_And_Resolve (High, Any_Real);
16888 Check_Real_Bound (Low);
16889 Check_Real_Bound (High);
16891 -- Obtain and set the range
16893 Low_Val := Expr_Value_R (Low);
16894 High_Val := Expr_Value_R (High);
16896 if Low_Val > High_Val then
16897 Error_Msg_NE ("?fixed point type& has null range", Def, T);
16902 -- The range for both the implicit base and the declared first subtype
16903 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
16904 -- set a temporary range in place. Note that the bounds of the base
16905 -- type will be widened to be symmetrical and to fill the available
16906 -- bits when the type is frozen.
16908 -- We could do this with all discrete types, and probably should, but
16909 -- we absolutely have to do it for fixed-point, since the end-points
16910 -- of the range and the size are determined by the small value, which
16911 -- could be reset before the freeze point.
16913 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
16914 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
16916 -- Complete definition of first subtype
16918 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
16919 Set_Etype (T, Implicit_Base);
16920 Init_Size_Align (T);
16921 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
16922 Set_Small_Value (T, Small_Val);
16923 Set_Delta_Value (T, Delta_Val);
16924 Set_Is_Constrained (T);
16926 end Ordinary_Fixed_Point_Type_Declaration;
16928 ----------------------------------------
16929 -- Prepare_Private_Subtype_Completion --
16930 ----------------------------------------
16932 procedure Prepare_Private_Subtype_Completion
16934 Related_Nod : Node_Id)
16936 Id_B : constant Entity_Id := Base_Type (Id);
16937 Full_B : constant Entity_Id := Full_View (Id_B);
16941 if Present (Full_B) then
16943 -- The Base_Type is already completed, we can complete the subtype
16944 -- now. We have to create a new entity with the same name, Thus we
16945 -- can't use Create_Itype.
16947 -- This is messy, should be fixed ???
16949 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
16950 Set_Is_Itype (Full);
16951 Set_Associated_Node_For_Itype (Full, Related_Nod);
16952 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
16955 -- The parent subtype may be private, but the base might not, in some
16956 -- nested instances. In that case, the subtype does not need to be
16957 -- exchanged. It would still be nice to make private subtypes and their
16958 -- bases consistent at all times ???
16960 if Is_Private_Type (Id_B) then
16961 Append_Elmt (Id, Private_Dependents (Id_B));
16964 end Prepare_Private_Subtype_Completion;
16966 ---------------------------
16967 -- Process_Discriminants --
16968 ---------------------------
16970 procedure Process_Discriminants
16972 Prev : Entity_Id := Empty)
16974 Elist : constant Elist_Id := New_Elmt_List;
16977 Discr_Number : Uint;
16978 Discr_Type : Entity_Id;
16979 Default_Present : Boolean := False;
16980 Default_Not_Present : Boolean := False;
16983 -- A composite type other than an array type can have discriminants.
16984 -- On entry, the current scope is the composite type.
16986 -- The discriminants are initially entered into the scope of the type
16987 -- via Enter_Name with the default Ekind of E_Void to prevent premature
16988 -- use, as explained at the end of this procedure.
16990 Discr := First (Discriminant_Specifications (N));
16991 while Present (Discr) loop
16992 Enter_Name (Defining_Identifier (Discr));
16994 -- For navigation purposes we add a reference to the discriminant
16995 -- in the entity for the type. If the current declaration is a
16996 -- completion, place references on the partial view. Otherwise the
16997 -- type is the current scope.
16999 if Present (Prev) then
17001 -- The references go on the partial view, if present. If the
17002 -- partial view has discriminants, the references have been
17003 -- generated already.
17005 if not Has_Discriminants (Prev) then
17006 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
17010 (Current_Scope, Defining_Identifier (Discr), 'd');
17013 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
17014 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
17016 -- Ada 2005 (AI-254)
17018 if Present (Access_To_Subprogram_Definition
17019 (Discriminant_Type (Discr)))
17020 and then Protected_Present (Access_To_Subprogram_Definition
17021 (Discriminant_Type (Discr)))
17024 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
17028 Find_Type (Discriminant_Type (Discr));
17029 Discr_Type := Etype (Discriminant_Type (Discr));
17031 if Error_Posted (Discriminant_Type (Discr)) then
17032 Discr_Type := Any_Type;
17036 if Is_Access_Type (Discr_Type) then
17038 -- Ada 2005 (AI-230): Access discriminant allowed in non-limited
17041 if Ada_Version < Ada_2005 then
17042 Check_Access_Discriminant_Requires_Limited
17043 (Discr, Discriminant_Type (Discr));
17046 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
17048 ("(Ada 83) access discriminant not allowed", Discr);
17051 elsif not Is_Discrete_Type (Discr_Type) then
17052 Error_Msg_N ("discriminants must have a discrete or access type",
17053 Discriminant_Type (Discr));
17056 Set_Etype (Defining_Identifier (Discr), Discr_Type);
17058 -- If a discriminant specification includes the assignment compound
17059 -- delimiter followed by an expression, the expression is the default
17060 -- expression of the discriminant; the default expression must be of
17061 -- the type of the discriminant. (RM 3.7.1) Since this expression is
17062 -- a default expression, we do the special preanalysis, since this
17063 -- expression does not freeze (see "Handling of Default and Per-
17064 -- Object Expressions" in spec of package Sem).
17066 if Present (Expression (Discr)) then
17067 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
17069 if Nkind (N) = N_Formal_Type_Declaration then
17071 ("discriminant defaults not allowed for formal type",
17072 Expression (Discr));
17074 -- Flag an error for a tagged type with defaulted discriminants,
17075 -- excluding limited tagged types when compiling for Ada 2012
17076 -- (see AI05-0214).
17078 elsif Is_Tagged_Type (Current_Scope)
17079 and then (not Is_Limited_Type (Current_Scope)
17080 or else Ada_Version < Ada_2012)
17081 and then Comes_From_Source (N)
17083 -- Note: see similar test in Check_Or_Process_Discriminants, to
17084 -- handle the (illegal) case of the completion of an untagged
17085 -- view with discriminants with defaults by a tagged full view.
17086 -- We skip the check if Discr does not come from source, to
17087 -- account for the case of an untagged derived type providing
17088 -- defaults for a renamed discriminant from a private untagged
17089 -- ancestor with a tagged full view (ACATS B460006).
17091 if Ada_Version >= Ada_2012 then
17093 ("discriminants of nonlimited tagged type cannot have"
17095 Expression (Discr));
17098 ("discriminants of tagged type cannot have defaults",
17099 Expression (Discr));
17103 Default_Present := True;
17104 Append_Elmt (Expression (Discr), Elist);
17106 -- Tag the defining identifiers for the discriminants with
17107 -- their corresponding default expressions from the tree.
17109 Set_Discriminant_Default_Value
17110 (Defining_Identifier (Discr), Expression (Discr));
17114 Default_Not_Present := True;
17117 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
17118 -- Discr_Type but with the null-exclusion attribute
17120 if Ada_Version >= Ada_2005 then
17122 -- Ada 2005 (AI-231): Static checks
17124 if Can_Never_Be_Null (Discr_Type) then
17125 Null_Exclusion_Static_Checks (Discr);
17127 elsif Is_Access_Type (Discr_Type)
17128 and then Null_Exclusion_Present (Discr)
17130 -- No need to check itypes because in their case this check
17131 -- was done at their point of creation
17133 and then not Is_Itype (Discr_Type)
17135 if Can_Never_Be_Null (Discr_Type) then
17137 ("`NOT NULL` not allowed (& already excludes null)",
17142 Set_Etype (Defining_Identifier (Discr),
17143 Create_Null_Excluding_Itype
17145 Related_Nod => Discr));
17147 -- Check for improper null exclusion if the type is otherwise
17148 -- legal for a discriminant.
17150 elsif Null_Exclusion_Present (Discr)
17151 and then Is_Discrete_Type (Discr_Type)
17154 ("null exclusion can only apply to an access type", Discr);
17157 -- Ada 2005 (AI-402): access discriminants of nonlimited types
17158 -- can't have defaults. Synchronized types, or types that are
17159 -- explicitly limited are fine, but special tests apply to derived
17160 -- types in generics: in a generic body we have to assume the
17161 -- worst, and therefore defaults are not allowed if the parent is
17162 -- a generic formal private type (see ACATS B370001).
17164 if Is_Access_Type (Discr_Type) then
17165 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
17166 or else not Default_Present
17167 or else Is_Limited_Record (Current_Scope)
17168 or else Is_Concurrent_Type (Current_Scope)
17169 or else Is_Concurrent_Record_Type (Current_Scope)
17170 or else Ekind (Current_Scope) = E_Limited_Private_Type
17172 if not Is_Derived_Type (Current_Scope)
17173 or else not Is_Generic_Type (Etype (Current_Scope))
17174 or else not In_Package_Body (Scope (Etype (Current_Scope)))
17175 or else Limited_Present
17176 (Type_Definition (Parent (Current_Scope)))
17181 Error_Msg_N ("access discriminants of nonlimited types",
17182 Expression (Discr));
17183 Error_Msg_N ("\cannot have defaults", Expression (Discr));
17186 elsif Present (Expression (Discr)) then
17188 ("(Ada 2005) access discriminants of nonlimited types",
17189 Expression (Discr));
17190 Error_Msg_N ("\cannot have defaults", Expression (Discr));
17198 -- An element list consisting of the default expressions of the
17199 -- discriminants is constructed in the above loop and used to set
17200 -- the Discriminant_Constraint attribute for the type. If an object
17201 -- is declared of this (record or task) type without any explicit
17202 -- discriminant constraint given, this element list will form the
17203 -- actual parameters for the corresponding initialization procedure
17206 Set_Discriminant_Constraint (Current_Scope, Elist);
17207 Set_Stored_Constraint (Current_Scope, No_Elist);
17209 -- Default expressions must be provided either for all or for none
17210 -- of the discriminants of a discriminant part. (RM 3.7.1)
17212 if Default_Present and then Default_Not_Present then
17214 ("incomplete specification of defaults for discriminants", N);
17217 -- The use of the name of a discriminant is not allowed in default
17218 -- expressions of a discriminant part if the specification of the
17219 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
17221 -- To detect this, the discriminant names are entered initially with an
17222 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
17223 -- attempt to use a void entity (for example in an expression that is
17224 -- type-checked) produces the error message: premature usage. Now after
17225 -- completing the semantic analysis of the discriminant part, we can set
17226 -- the Ekind of all the discriminants appropriately.
17228 Discr := First (Discriminant_Specifications (N));
17229 Discr_Number := Uint_1;
17230 while Present (Discr) loop
17231 Id := Defining_Identifier (Discr);
17232 Set_Ekind (Id, E_Discriminant);
17233 Init_Component_Location (Id);
17235 Set_Discriminant_Number (Id, Discr_Number);
17237 -- Make sure this is always set, even in illegal programs
17239 Set_Corresponding_Discriminant (Id, Empty);
17241 -- Initialize the Original_Record_Component to the entity itself.
17242 -- Inherit_Components will propagate the right value to
17243 -- discriminants in derived record types.
17245 Set_Original_Record_Component (Id, Id);
17247 -- Create the discriminal for the discriminant
17249 Build_Discriminal (Id);
17252 Discr_Number := Discr_Number + 1;
17255 Set_Has_Discriminants (Current_Scope);
17256 end Process_Discriminants;
17258 -----------------------
17259 -- Process_Full_View --
17260 -----------------------
17262 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
17263 Priv_Parent : Entity_Id;
17264 Full_Parent : Entity_Id;
17265 Full_Indic : Node_Id;
17267 procedure Collect_Implemented_Interfaces
17269 Ifaces : Elist_Id);
17270 -- Ada 2005: Gather all the interfaces that Typ directly or
17271 -- inherently implements. Duplicate entries are not added to
17272 -- the list Ifaces.
17274 ------------------------------------
17275 -- Collect_Implemented_Interfaces --
17276 ------------------------------------
17278 procedure Collect_Implemented_Interfaces
17283 Iface_Elmt : Elmt_Id;
17286 -- Abstract interfaces are only associated with tagged record types
17288 if not Is_Tagged_Type (Typ)
17289 or else not Is_Record_Type (Typ)
17294 -- Recursively climb to the ancestors
17296 if Etype (Typ) /= Typ
17298 -- Protect the frontend against wrong cyclic declarations like:
17300 -- type B is new A with private;
17301 -- type C is new A with private;
17303 -- type B is new C with null record;
17304 -- type C is new B with null record;
17306 and then Etype (Typ) /= Priv_T
17307 and then Etype (Typ) /= Full_T
17309 -- Keep separate the management of private type declarations
17311 if Ekind (Typ) = E_Record_Type_With_Private then
17313 -- Handle the following erroneous case:
17314 -- type Private_Type is tagged private;
17316 -- type Private_Type is new Type_Implementing_Iface;
17318 if Present (Full_View (Typ))
17319 and then Etype (Typ) /= Full_View (Typ)
17321 if Is_Interface (Etype (Typ)) then
17322 Append_Unique_Elmt (Etype (Typ), Ifaces);
17325 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
17328 -- Non-private types
17331 if Is_Interface (Etype (Typ)) then
17332 Append_Unique_Elmt (Etype (Typ), Ifaces);
17335 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
17339 -- Handle entities in the list of abstract interfaces
17341 if Present (Interfaces (Typ)) then
17342 Iface_Elmt := First_Elmt (Interfaces (Typ));
17343 while Present (Iface_Elmt) loop
17344 Iface := Node (Iface_Elmt);
17346 pragma Assert (Is_Interface (Iface));
17348 if not Contain_Interface (Iface, Ifaces) then
17349 Append_Elmt (Iface, Ifaces);
17350 Collect_Implemented_Interfaces (Iface, Ifaces);
17353 Next_Elmt (Iface_Elmt);
17356 end Collect_Implemented_Interfaces;
17358 -- Start of processing for Process_Full_View
17361 -- First some sanity checks that must be done after semantic
17362 -- decoration of the full view and thus cannot be placed with other
17363 -- similar checks in Find_Type_Name
17365 if not Is_Limited_Type (Priv_T)
17366 and then (Is_Limited_Type (Full_T)
17367 or else Is_Limited_Composite (Full_T))
17370 ("completion of nonlimited type cannot be limited", Full_T);
17371 Explain_Limited_Type (Full_T, Full_T);
17373 elsif Is_Abstract_Type (Full_T)
17374 and then not Is_Abstract_Type (Priv_T)
17377 ("completion of nonabstract type cannot be abstract", Full_T);
17379 elsif Is_Tagged_Type (Priv_T)
17380 and then Is_Limited_Type (Priv_T)
17381 and then not Is_Limited_Type (Full_T)
17383 -- If pragma CPP_Class was applied to the private declaration
17384 -- propagate the limitedness to the full-view
17386 if Is_CPP_Class (Priv_T) then
17387 Set_Is_Limited_Record (Full_T);
17389 -- GNAT allow its own definition of Limited_Controlled to disobey
17390 -- this rule in order in ease the implementation. This test is safe
17391 -- because Root_Controlled is defined in a private system child.
17393 elsif Is_RTE (Etype (Full_T), RE_Root_Controlled) then
17394 Set_Is_Limited_Composite (Full_T);
17397 ("completion of limited tagged type must be limited", Full_T);
17400 elsif Is_Generic_Type (Priv_T) then
17401 Error_Msg_N ("generic type cannot have a completion", Full_T);
17404 -- Check that ancestor interfaces of private and full views are
17405 -- consistent. We omit this check for synchronized types because
17406 -- they are performed on the corresponding record type when frozen.
17408 if Ada_Version >= Ada_2005
17409 and then Is_Tagged_Type (Priv_T)
17410 and then Is_Tagged_Type (Full_T)
17411 and then not Is_Concurrent_Type (Full_T)
17415 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
17416 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
17419 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
17420 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
17422 -- Ada 2005 (AI-251): The partial view shall be a descendant of
17423 -- an interface type if and only if the full type is descendant
17424 -- of the interface type (AARM 7.3 (7.3/2).
17426 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
17428 if Present (Iface) then
17430 ("interface & not implemented by full type " &
17431 "(RM-2005 7.3 (7.3/2))", Priv_T, Iface);
17434 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
17436 if Present (Iface) then
17438 ("interface & not implemented by partial view " &
17439 "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
17444 if Is_Tagged_Type (Priv_T)
17445 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
17446 and then Is_Derived_Type (Full_T)
17448 Priv_Parent := Etype (Priv_T);
17450 -- The full view of a private extension may have been transformed
17451 -- into an unconstrained derived type declaration and a subtype
17452 -- declaration (see build_derived_record_type for details).
17454 if Nkind (N) = N_Subtype_Declaration then
17455 Full_Indic := Subtype_Indication (N);
17456 Full_Parent := Etype (Base_Type (Full_T));
17458 Full_Indic := Subtype_Indication (Type_Definition (N));
17459 Full_Parent := Etype (Full_T);
17462 -- Check that the parent type of the full type is a descendant of
17463 -- the ancestor subtype given in the private extension. If either
17464 -- entity has an Etype equal to Any_Type then we had some previous
17465 -- error situation [7.3(8)].
17467 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
17470 -- Ada 2005 (AI-251): Interfaces in the full-typ can be given in
17471 -- any order. Therefore we don't have to check that its parent must
17472 -- be a descendant of the parent of the private type declaration.
17474 elsif Is_Interface (Priv_Parent)
17475 and then Is_Interface (Full_Parent)
17479 -- Ada 2005 (AI-251): If the parent of the private type declaration
17480 -- is an interface there is no need to check that it is an ancestor
17481 -- of the associated full type declaration. The required tests for
17482 -- this case are performed by Build_Derived_Record_Type.
17484 elsif not Is_Interface (Base_Type (Priv_Parent))
17485 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
17488 ("parent of full type must descend from parent"
17489 & " of private extension", Full_Indic);
17491 -- First check a formal restriction, and then proceed with checking
17492 -- Ada rules. Since the formal restriction is not a serious error, we
17493 -- don't prevent further error detection for this check, hence the
17498 -- In formal mode, when completing a private extension the type
17499 -- named in the private part must be exactly the same as that
17500 -- named in the visible part.
17502 if Priv_Parent /= Full_Parent then
17503 Error_Msg_Name_1 := Chars (Priv_Parent);
17504 Check_SPARK_Restriction ("% expected", Full_Indic);
17507 -- Check the rules of 7.3(10): if the private extension inherits
17508 -- known discriminants, then the full type must also inherit those
17509 -- discriminants from the same (ancestor) type, and the parent
17510 -- subtype of the full type must be constrained if and only if
17511 -- the ancestor subtype of the private extension is constrained.
17513 if No (Discriminant_Specifications (Parent (Priv_T)))
17514 and then not Has_Unknown_Discriminants (Priv_T)
17515 and then Has_Discriminants (Base_Type (Priv_Parent))
17518 Priv_Indic : constant Node_Id :=
17519 Subtype_Indication (Parent (Priv_T));
17521 Priv_Constr : constant Boolean :=
17522 Is_Constrained (Priv_Parent)
17524 Nkind (Priv_Indic) = N_Subtype_Indication
17526 Is_Constrained (Entity (Priv_Indic));
17528 Full_Constr : constant Boolean :=
17529 Is_Constrained (Full_Parent)
17531 Nkind (Full_Indic) = N_Subtype_Indication
17533 Is_Constrained (Entity (Full_Indic));
17535 Priv_Discr : Entity_Id;
17536 Full_Discr : Entity_Id;
17539 Priv_Discr := First_Discriminant (Priv_Parent);
17540 Full_Discr := First_Discriminant (Full_Parent);
17541 while Present (Priv_Discr) and then Present (Full_Discr) loop
17542 if Original_Record_Component (Priv_Discr) =
17543 Original_Record_Component (Full_Discr)
17545 Corresponding_Discriminant (Priv_Discr) =
17546 Corresponding_Discriminant (Full_Discr)
17553 Next_Discriminant (Priv_Discr);
17554 Next_Discriminant (Full_Discr);
17557 if Present (Priv_Discr) or else Present (Full_Discr) then
17559 ("full view must inherit discriminants of the parent"
17560 & " type used in the private extension", Full_Indic);
17562 elsif Priv_Constr and then not Full_Constr then
17564 ("parent subtype of full type must be constrained",
17567 elsif Full_Constr and then not Priv_Constr then
17569 ("parent subtype of full type must be unconstrained",
17574 -- Check the rules of 7.3(12): if a partial view has neither
17575 -- known or unknown discriminants, then the full type
17576 -- declaration shall define a definite subtype.
17578 elsif not Has_Unknown_Discriminants (Priv_T)
17579 and then not Has_Discriminants (Priv_T)
17580 and then not Is_Constrained (Full_T)
17583 ("full view must define a constrained type if partial view"
17584 & " has no discriminants", Full_T);
17587 -- ??????? Do we implement the following properly ?????
17588 -- If the ancestor subtype of a private extension has constrained
17589 -- discriminants, then the parent subtype of the full view shall
17590 -- impose a statically matching constraint on those discriminants
17595 -- For untagged types, verify that a type without discriminants
17596 -- is not completed with an unconstrained type.
17598 if not Is_Indefinite_Subtype (Priv_T)
17599 and then Is_Indefinite_Subtype (Full_T)
17601 Error_Msg_N ("full view of type must be definite subtype", Full_T);
17605 -- AI-419: verify that the use of "limited" is consistent
17608 Orig_Decl : constant Node_Id := Original_Node (N);
17611 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
17612 and then not Limited_Present (Parent (Priv_T))
17613 and then not Synchronized_Present (Parent (Priv_T))
17614 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
17616 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
17617 and then Limited_Present (Type_Definition (Orig_Decl))
17620 ("full view of non-limited extension cannot be limited", N);
17624 -- Ada 2005 (AI-443): A synchronized private extension must be
17625 -- completed by a task or protected type.
17627 if Ada_Version >= Ada_2005
17628 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
17629 and then Synchronized_Present (Parent (Priv_T))
17630 and then not Is_Concurrent_Type (Full_T)
17632 Error_Msg_N ("full view of synchronized extension must " &
17633 "be synchronized type", N);
17636 -- Ada 2005 AI-363: if the full view has discriminants with
17637 -- defaults, it is illegal to declare constrained access subtypes
17638 -- whose designated type is the current type. This allows objects
17639 -- of the type that are declared in the heap to be unconstrained.
17641 if not Has_Unknown_Discriminants (Priv_T)
17642 and then not Has_Discriminants (Priv_T)
17643 and then Has_Discriminants (Full_T)
17645 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
17647 Set_Has_Constrained_Partial_View (Full_T);
17648 Set_Has_Constrained_Partial_View (Priv_T);
17651 -- Create a full declaration for all its subtypes recorded in
17652 -- Private_Dependents and swap them similarly to the base type. These
17653 -- are subtypes that have been define before the full declaration of
17654 -- the private type. We also swap the entry in Private_Dependents list
17655 -- so we can properly restore the private view on exit from the scope.
17658 Priv_Elmt : Elmt_Id;
17663 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
17664 while Present (Priv_Elmt) loop
17665 Priv := Node (Priv_Elmt);
17667 if Ekind_In (Priv, E_Private_Subtype,
17668 E_Limited_Private_Subtype,
17669 E_Record_Subtype_With_Private)
17671 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
17672 Set_Is_Itype (Full);
17673 Set_Parent (Full, Parent (Priv));
17674 Set_Associated_Node_For_Itype (Full, N);
17676 -- Now we need to complete the private subtype, but since the
17677 -- base type has already been swapped, we must also swap the
17678 -- subtypes (and thus, reverse the arguments in the call to
17679 -- Complete_Private_Subtype).
17681 Copy_And_Swap (Priv, Full);
17682 Complete_Private_Subtype (Full, Priv, Full_T, N);
17683 Replace_Elmt (Priv_Elmt, Full);
17686 Next_Elmt (Priv_Elmt);
17690 -- If the private view was tagged, copy the new primitive operations
17691 -- from the private view to the full view.
17693 if Is_Tagged_Type (Full_T) then
17695 Disp_Typ : Entity_Id;
17696 Full_List : Elist_Id;
17698 Prim_Elmt : Elmt_Id;
17699 Priv_List : Elist_Id;
17703 L : Elist_Id) return Boolean;
17704 -- Determine whether list L contains element E
17712 L : Elist_Id) return Boolean
17714 List_Elmt : Elmt_Id;
17717 List_Elmt := First_Elmt (L);
17718 while Present (List_Elmt) loop
17719 if Node (List_Elmt) = E then
17723 Next_Elmt (List_Elmt);
17729 -- Start of processing
17732 if Is_Tagged_Type (Priv_T) then
17733 Priv_List := Primitive_Operations (Priv_T);
17734 Prim_Elmt := First_Elmt (Priv_List);
17736 -- In the case of a concurrent type completing a private tagged
17737 -- type, primitives may have been declared in between the two
17738 -- views. These subprograms need to be wrapped the same way
17739 -- entries and protected procedures are handled because they
17740 -- cannot be directly shared by the two views.
17742 if Is_Concurrent_Type (Full_T) then
17744 Conc_Typ : constant Entity_Id :=
17745 Corresponding_Record_Type (Full_T);
17746 Curr_Nod : Node_Id := Parent (Conc_Typ);
17747 Wrap_Spec : Node_Id;
17750 while Present (Prim_Elmt) loop
17751 Prim := Node (Prim_Elmt);
17753 if Comes_From_Source (Prim)
17754 and then not Is_Abstract_Subprogram (Prim)
17757 Make_Subprogram_Declaration (Sloc (Prim),
17761 Obj_Typ => Conc_Typ,
17763 Parameter_Specifications (
17766 Insert_After (Curr_Nod, Wrap_Spec);
17767 Curr_Nod := Wrap_Spec;
17769 Analyze (Wrap_Spec);
17772 Next_Elmt (Prim_Elmt);
17778 -- For non-concurrent types, transfer explicit primitives, but
17779 -- omit those inherited from the parent of the private view
17780 -- since they will be re-inherited later on.
17783 Full_List := Primitive_Operations (Full_T);
17785 while Present (Prim_Elmt) loop
17786 Prim := Node (Prim_Elmt);
17788 if Comes_From_Source (Prim)
17789 and then not Contains (Prim, Full_List)
17791 Append_Elmt (Prim, Full_List);
17794 Next_Elmt (Prim_Elmt);
17798 -- Untagged private view
17801 Full_List := Primitive_Operations (Full_T);
17803 -- In this case the partial view is untagged, so here we locate
17804 -- all of the earlier primitives that need to be treated as
17805 -- dispatching (those that appear between the two views). Note
17806 -- that these additional operations must all be new operations
17807 -- (any earlier operations that override inherited operations
17808 -- of the full view will already have been inserted in the
17809 -- primitives list, marked by Check_Operation_From_Private_View
17810 -- as dispatching. Note that implicit "/=" operators are
17811 -- excluded from being added to the primitives list since they
17812 -- shouldn't be treated as dispatching (tagged "/=" is handled
17815 Prim := Next_Entity (Full_T);
17816 while Present (Prim) and then Prim /= Priv_T loop
17817 if Ekind_In (Prim, E_Procedure, E_Function) then
17818 Disp_Typ := Find_Dispatching_Type (Prim);
17820 if Disp_Typ = Full_T
17821 and then (Chars (Prim) /= Name_Op_Ne
17822 or else Comes_From_Source (Prim))
17824 Check_Controlling_Formals (Full_T, Prim);
17826 if not Is_Dispatching_Operation (Prim) then
17827 Append_Elmt (Prim, Full_List);
17828 Set_Is_Dispatching_Operation (Prim, True);
17829 Set_DT_Position (Prim, No_Uint);
17832 elsif Is_Dispatching_Operation (Prim)
17833 and then Disp_Typ /= Full_T
17836 -- Verify that it is not otherwise controlled by a
17837 -- formal or a return value of type T.
17839 Check_Controlling_Formals (Disp_Typ, Prim);
17843 Next_Entity (Prim);
17847 -- For the tagged case, the two views can share the same primitive
17848 -- operations list and the same class-wide type. Update attributes
17849 -- of the class-wide type which depend on the full declaration.
17851 if Is_Tagged_Type (Priv_T) then
17852 Set_Direct_Primitive_Operations (Priv_T, Full_List);
17853 Set_Class_Wide_Type
17854 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
17856 Set_Has_Task (Class_Wide_Type (Priv_T), Has_Task (Full_T));
17861 -- Ada 2005 AI 161: Check preelaboratable initialization consistency
17863 if Known_To_Have_Preelab_Init (Priv_T) then
17865 -- Case where there is a pragma Preelaborable_Initialization. We
17866 -- always allow this in predefined units, which is a bit of a kludge,
17867 -- but it means we don't have to struggle to meet the requirements in
17868 -- the RM for having Preelaborable Initialization. Otherwise we
17869 -- require that the type meets the RM rules. But we can't check that
17870 -- yet, because of the rule about overriding Initialize, so we simply
17871 -- set a flag that will be checked at freeze time.
17873 if not In_Predefined_Unit (Full_T) then
17874 Set_Must_Have_Preelab_Init (Full_T);
17878 -- If pragma CPP_Class was applied to the private type declaration,
17879 -- propagate it now to the full type declaration.
17881 if Is_CPP_Class (Priv_T) then
17882 Set_Is_CPP_Class (Full_T);
17883 Set_Convention (Full_T, Convention_CPP);
17886 -- If the private view has user specified stream attributes, then so has
17889 -- Why the test, how could these flags be already set in Full_T ???
17891 if Has_Specified_Stream_Read (Priv_T) then
17892 Set_Has_Specified_Stream_Read (Full_T);
17895 if Has_Specified_Stream_Write (Priv_T) then
17896 Set_Has_Specified_Stream_Write (Full_T);
17899 if Has_Specified_Stream_Input (Priv_T) then
17900 Set_Has_Specified_Stream_Input (Full_T);
17903 if Has_Specified_Stream_Output (Priv_T) then
17904 Set_Has_Specified_Stream_Output (Full_T);
17907 -- Propagate invariants to full type
17909 if Has_Invariants (Priv_T) then
17910 Set_Has_Invariants (Full_T);
17911 Set_Invariant_Procedure (Full_T, Invariant_Procedure (Priv_T));
17914 if Has_Inheritable_Invariants (Priv_T) then
17915 Set_Has_Inheritable_Invariants (Full_T);
17918 -- Propagate predicates to full type
17920 if Has_Predicates (Priv_T) then
17921 Set_Predicate_Function (Priv_T, Predicate_Function (Full_T));
17922 Set_Has_Predicates (Priv_T);
17924 end Process_Full_View;
17926 -----------------------------------
17927 -- Process_Incomplete_Dependents --
17928 -----------------------------------
17930 procedure Process_Incomplete_Dependents
17932 Full_T : Entity_Id;
17935 Inc_Elmt : Elmt_Id;
17936 Priv_Dep : Entity_Id;
17937 New_Subt : Entity_Id;
17939 Disc_Constraint : Elist_Id;
17942 if No (Private_Dependents (Inc_T)) then
17946 -- Itypes that may be generated by the completion of an incomplete
17947 -- subtype are not used by the back-end and not attached to the tree.
17948 -- They are created only for constraint-checking purposes.
17950 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
17951 while Present (Inc_Elmt) loop
17952 Priv_Dep := Node (Inc_Elmt);
17954 if Ekind (Priv_Dep) = E_Subprogram_Type then
17956 -- An Access_To_Subprogram type may have a return type or a
17957 -- parameter type that is incomplete. Replace with the full view.
17959 if Etype (Priv_Dep) = Inc_T then
17960 Set_Etype (Priv_Dep, Full_T);
17964 Formal : Entity_Id;
17967 Formal := First_Formal (Priv_Dep);
17968 while Present (Formal) loop
17969 if Etype (Formal) = Inc_T then
17970 Set_Etype (Formal, Full_T);
17973 Next_Formal (Formal);
17977 elsif Is_Overloadable (Priv_Dep) then
17979 -- If a subprogram in the incomplete dependents list is primitive
17980 -- for a tagged full type then mark it as a dispatching operation,
17981 -- check whether it overrides an inherited subprogram, and check
17982 -- restrictions on its controlling formals. Note that a protected
17983 -- operation is never dispatching: only its wrapper operation
17984 -- (which has convention Ada) is.
17986 if Is_Tagged_Type (Full_T)
17987 and then Is_Primitive (Priv_Dep)
17988 and then Convention (Priv_Dep) /= Convention_Protected
17990 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
17991 Set_Is_Dispatching_Operation (Priv_Dep);
17992 Check_Controlling_Formals (Full_T, Priv_Dep);
17995 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
17997 -- Can happen during processing of a body before the completion
17998 -- of a TA type. Ignore, because spec is also on dependent list.
18002 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
18003 -- corresponding subtype of the full view.
18005 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype then
18006 Set_Subtype_Indication
18007 (Parent (Priv_Dep), New_Reference_To (Full_T, Sloc (Priv_Dep)));
18008 Set_Etype (Priv_Dep, Full_T);
18009 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
18010 Set_Analyzed (Parent (Priv_Dep), False);
18012 -- Reanalyze the declaration, suppressing the call to
18013 -- Enter_Name to avoid duplicate names.
18015 Analyze_Subtype_Declaration
18016 (N => Parent (Priv_Dep),
18019 -- Dependent is a subtype
18022 -- We build a new subtype indication using the full view of the
18023 -- incomplete parent. The discriminant constraints have been
18024 -- elaborated already at the point of the subtype declaration.
18026 New_Subt := Create_Itype (E_Void, N);
18028 if Has_Discriminants (Full_T) then
18029 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
18031 Disc_Constraint := No_Elist;
18034 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
18035 Set_Full_View (Priv_Dep, New_Subt);
18038 Next_Elmt (Inc_Elmt);
18040 end Process_Incomplete_Dependents;
18042 --------------------------------
18043 -- Process_Range_Expr_In_Decl --
18044 --------------------------------
18046 procedure Process_Range_Expr_In_Decl
18049 Check_List : List_Id := Empty_List;
18050 R_Check_Off : Boolean := False;
18051 In_Iter_Schm : Boolean := False)
18054 R_Checks : Check_Result;
18055 Insert_Node : Node_Id;
18056 Def_Id : Entity_Id;
18059 Analyze_And_Resolve (R, Base_Type (T));
18061 if Nkind (R) = N_Range then
18063 -- In SPARK, all ranges should be static, with the exception of the
18064 -- discrete type definition of a loop parameter specification.
18066 if not In_Iter_Schm
18067 and then not Is_Static_Range (R)
18069 Check_SPARK_Restriction ("range should be static", R);
18072 Lo := Low_Bound (R);
18073 Hi := High_Bound (R);
18075 -- We need to ensure validity of the bounds here, because if we
18076 -- go ahead and do the expansion, then the expanded code will get
18077 -- analyzed with range checks suppressed and we miss the check.
18079 Validity_Check_Range (R);
18081 -- If there were errors in the declaration, try and patch up some
18082 -- common mistakes in the bounds. The cases handled are literals
18083 -- which are Integer where the expected type is Real and vice versa.
18084 -- These corrections allow the compilation process to proceed further
18085 -- along since some basic assumptions of the format of the bounds
18088 if Etype (R) = Any_Type then
18090 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
18092 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
18094 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
18096 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
18098 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
18100 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
18102 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
18104 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
18111 -- If the bounds of the range have been mistakenly given as string
18112 -- literals (perhaps in place of character literals), then an error
18113 -- has already been reported, but we rewrite the string literal as a
18114 -- bound of the range's type to avoid blowups in later processing
18115 -- that looks at static values.
18117 if Nkind (Lo) = N_String_Literal then
18119 Make_Attribute_Reference (Sloc (Lo),
18120 Attribute_Name => Name_First,
18121 Prefix => New_Reference_To (T, Sloc (Lo))));
18122 Analyze_And_Resolve (Lo);
18125 if Nkind (Hi) = N_String_Literal then
18127 Make_Attribute_Reference (Sloc (Hi),
18128 Attribute_Name => Name_First,
18129 Prefix => New_Reference_To (T, Sloc (Hi))));
18130 Analyze_And_Resolve (Hi);
18133 -- If bounds aren't scalar at this point then exit, avoiding
18134 -- problems with further processing of the range in this procedure.
18136 if not Is_Scalar_Type (Etype (Lo)) then
18140 -- Resolve (actually Sem_Eval) has checked that the bounds are in
18141 -- then range of the base type. Here we check whether the bounds
18142 -- are in the range of the subtype itself. Note that if the bounds
18143 -- represent the null range the Constraint_Error exception should
18146 -- ??? The following code should be cleaned up as follows
18148 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
18149 -- is done in the call to Range_Check (R, T); below
18151 -- 2. The use of R_Check_Off should be investigated and possibly
18152 -- removed, this would clean up things a bit.
18154 if Is_Null_Range (Lo, Hi) then
18158 -- Capture values of bounds and generate temporaries for them
18159 -- if needed, before applying checks, since checks may cause
18160 -- duplication of the expression without forcing evaluation.
18162 if Expander_Active then
18163 Force_Evaluation (Lo);
18164 Force_Evaluation (Hi);
18167 -- We use a flag here instead of suppressing checks on the
18168 -- type because the type we check against isn't necessarily
18169 -- the place where we put the check.
18171 if not R_Check_Off then
18172 R_Checks := Get_Range_Checks (R, T);
18174 -- Look up tree to find an appropriate insertion point. We
18175 -- can't just use insert_actions because later processing
18176 -- depends on the insertion node. Prior to Ada2012 the
18177 -- insertion point could only be a declaration or a loop, but
18178 -- quantified expressions can appear within any context in an
18179 -- expression, and the insertion point can be any statement,
18180 -- pragma, or declaration.
18182 Insert_Node := Parent (R);
18183 while Present (Insert_Node) loop
18185 Nkind (Insert_Node) in N_Declaration
18188 (Insert_Node, N_Component_Declaration,
18189 N_Loop_Parameter_Specification,
18190 N_Function_Specification,
18191 N_Procedure_Specification);
18193 exit when Nkind (Insert_Node) in N_Later_Decl_Item
18194 or else Nkind (Insert_Node) in
18195 N_Statement_Other_Than_Procedure_Call
18196 or else Nkind_In (Insert_Node, N_Procedure_Call_Statement,
18199 Insert_Node := Parent (Insert_Node);
18202 -- Why would Type_Decl not be present??? Without this test,
18203 -- short regression tests fail.
18205 if Present (Insert_Node) then
18207 -- Case of loop statement. Verify that the range is part
18208 -- of the subtype indication of the iteration scheme.
18210 if Nkind (Insert_Node) = N_Loop_Statement then
18215 Indic := Parent (R);
18216 while Present (Indic)
18217 and then Nkind (Indic) /= N_Subtype_Indication
18219 Indic := Parent (Indic);
18222 if Present (Indic) then
18223 Def_Id := Etype (Subtype_Mark (Indic));
18225 Insert_Range_Checks
18229 Sloc (Insert_Node),
18231 Do_Before => True);
18235 -- Insertion before a declaration. If the declaration
18236 -- includes discriminants, the list of applicable checks
18237 -- is given by the caller.
18239 elsif Nkind (Insert_Node) in N_Declaration then
18240 Def_Id := Defining_Identifier (Insert_Node);
18242 if (Ekind (Def_Id) = E_Record_Type
18243 and then Depends_On_Discriminant (R))
18245 (Ekind (Def_Id) = E_Protected_Type
18246 and then Has_Discriminants (Def_Id))
18248 Append_Range_Checks
18250 Check_List, Def_Id, Sloc (Insert_Node), R);
18253 Insert_Range_Checks
18255 Insert_Node, Def_Id, Sloc (Insert_Node), R);
18259 -- Insertion before a statement. Range appears in the
18260 -- context of a quantified expression. Insertion will
18261 -- take place when expression is expanded.
18270 -- Case of other than an explicit N_Range node
18272 elsif Expander_Active then
18273 Get_Index_Bounds (R, Lo, Hi);
18274 Force_Evaluation (Lo);
18275 Force_Evaluation (Hi);
18277 end Process_Range_Expr_In_Decl;
18279 --------------------------------------
18280 -- Process_Real_Range_Specification --
18281 --------------------------------------
18283 procedure Process_Real_Range_Specification (Def : Node_Id) is
18284 Spec : constant Node_Id := Real_Range_Specification (Def);
18287 Err : Boolean := False;
18289 procedure Analyze_Bound (N : Node_Id);
18290 -- Analyze and check one bound
18292 -------------------
18293 -- Analyze_Bound --
18294 -------------------
18296 procedure Analyze_Bound (N : Node_Id) is
18298 Analyze_And_Resolve (N, Any_Real);
18300 if not Is_OK_Static_Expression (N) then
18301 Flag_Non_Static_Expr
18302 ("bound in real type definition is not static!", N);
18307 -- Start of processing for Process_Real_Range_Specification
18310 if Present (Spec) then
18311 Lo := Low_Bound (Spec);
18312 Hi := High_Bound (Spec);
18313 Analyze_Bound (Lo);
18314 Analyze_Bound (Hi);
18316 -- If error, clear away junk range specification
18319 Set_Real_Range_Specification (Def, Empty);
18322 end Process_Real_Range_Specification;
18324 ---------------------
18325 -- Process_Subtype --
18326 ---------------------
18328 function Process_Subtype
18330 Related_Nod : Node_Id;
18331 Related_Id : Entity_Id := Empty;
18332 Suffix : Character := ' ') return Entity_Id
18335 Def_Id : Entity_Id;
18336 Error_Node : Node_Id;
18337 Full_View_Id : Entity_Id;
18338 Subtype_Mark_Id : Entity_Id;
18340 May_Have_Null_Exclusion : Boolean;
18342 procedure Check_Incomplete (T : Entity_Id);
18343 -- Called to verify that an incomplete type is not used prematurely
18345 ----------------------
18346 -- Check_Incomplete --
18347 ----------------------
18349 procedure Check_Incomplete (T : Entity_Id) is
18351 -- Ada 2005 (AI-412): Incomplete subtypes are legal
18353 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
18355 not (Ada_Version >= Ada_2005
18357 (Nkind (Parent (T)) = N_Subtype_Declaration
18359 (Nkind (Parent (T)) = N_Subtype_Indication
18360 and then Nkind (Parent (Parent (T))) =
18361 N_Subtype_Declaration)))
18363 Error_Msg_N ("invalid use of type before its full declaration", T);
18365 end Check_Incomplete;
18367 -- Start of processing for Process_Subtype
18370 -- Case of no constraints present
18372 if Nkind (S) /= N_Subtype_Indication then
18374 Check_Incomplete (S);
18377 -- Ada 2005 (AI-231): Static check
18379 if Ada_Version >= Ada_2005
18380 and then Present (P)
18381 and then Null_Exclusion_Present (P)
18382 and then Nkind (P) /= N_Access_To_Object_Definition
18383 and then not Is_Access_Type (Entity (S))
18385 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
18388 -- The following is ugly, can't we have a range or even a flag???
18390 May_Have_Null_Exclusion :=
18391 Nkind_In (P, N_Access_Definition,
18392 N_Access_Function_Definition,
18393 N_Access_Procedure_Definition,
18394 N_Access_To_Object_Definition,
18396 N_Component_Definition)
18398 Nkind_In (P, N_Derived_Type_Definition,
18399 N_Discriminant_Specification,
18400 N_Formal_Object_Declaration,
18401 N_Object_Declaration,
18402 N_Object_Renaming_Declaration,
18403 N_Parameter_Specification,
18404 N_Subtype_Declaration);
18406 -- Create an Itype that is a duplicate of Entity (S) but with the
18407 -- null-exclusion attribute.
18409 if May_Have_Null_Exclusion
18410 and then Is_Access_Type (Entity (S))
18411 and then Null_Exclusion_Present (P)
18413 -- No need to check the case of an access to object definition.
18414 -- It is correct to define double not-null pointers.
18417 -- type Not_Null_Int_Ptr is not null access Integer;
18418 -- type Acc is not null access Not_Null_Int_Ptr;
18420 and then Nkind (P) /= N_Access_To_Object_Definition
18422 if Can_Never_Be_Null (Entity (S)) then
18423 case Nkind (Related_Nod) is
18424 when N_Full_Type_Declaration =>
18425 if Nkind (Type_Definition (Related_Nod))
18426 in N_Array_Type_Definition
18430 (Component_Definition
18431 (Type_Definition (Related_Nod)));
18434 Subtype_Indication (Type_Definition (Related_Nod));
18437 when N_Subtype_Declaration =>
18438 Error_Node := Subtype_Indication (Related_Nod);
18440 when N_Object_Declaration =>
18441 Error_Node := Object_Definition (Related_Nod);
18443 when N_Component_Declaration =>
18445 Subtype_Indication (Component_Definition (Related_Nod));
18447 when N_Allocator =>
18448 Error_Node := Expression (Related_Nod);
18451 pragma Assert (False);
18452 Error_Node := Related_Nod;
18456 ("`NOT NULL` not allowed (& already excludes null)",
18462 Create_Null_Excluding_Itype
18464 Related_Nod => P));
18465 Set_Entity (S, Etype (S));
18470 -- Case of constraint present, so that we have an N_Subtype_Indication
18471 -- node (this node is created only if constraints are present).
18474 Find_Type (Subtype_Mark (S));
18476 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
18478 (Nkind (Parent (S)) = N_Subtype_Declaration
18479 and then Is_Itype (Defining_Identifier (Parent (S))))
18481 Check_Incomplete (Subtype_Mark (S));
18485 Subtype_Mark_Id := Entity (Subtype_Mark (S));
18487 -- Explicit subtype declaration case
18489 if Nkind (P) = N_Subtype_Declaration then
18490 Def_Id := Defining_Identifier (P);
18492 -- Explicit derived type definition case
18494 elsif Nkind (P) = N_Derived_Type_Definition then
18495 Def_Id := Defining_Identifier (Parent (P));
18497 -- Implicit case, the Def_Id must be created as an implicit type.
18498 -- The one exception arises in the case of concurrent types, array
18499 -- and access types, where other subsidiary implicit types may be
18500 -- created and must appear before the main implicit type. In these
18501 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
18502 -- has not yet been called to create Def_Id.
18505 if Is_Array_Type (Subtype_Mark_Id)
18506 or else Is_Concurrent_Type (Subtype_Mark_Id)
18507 or else Is_Access_Type (Subtype_Mark_Id)
18511 -- For the other cases, we create a new unattached Itype,
18512 -- and set the indication to ensure it gets attached later.
18516 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
18520 -- If the kind of constraint is invalid for this kind of type,
18521 -- then give an error, and then pretend no constraint was given.
18523 if not Is_Valid_Constraint_Kind
18524 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
18527 ("incorrect constraint for this kind of type", Constraint (S));
18529 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
18531 -- Set Ekind of orphan itype, to prevent cascaded errors
18533 if Present (Def_Id) then
18534 Set_Ekind (Def_Id, Ekind (Any_Type));
18537 -- Make recursive call, having got rid of the bogus constraint
18539 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
18542 -- Remaining processing depends on type
18544 case Ekind (Subtype_Mark_Id) is
18545 when Access_Kind =>
18546 Constrain_Access (Def_Id, S, Related_Nod);
18549 and then Is_Itype (Designated_Type (Def_Id))
18550 and then Nkind (Related_Nod) = N_Subtype_Declaration
18551 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
18553 Build_Itype_Reference
18554 (Designated_Type (Def_Id), Related_Nod);
18558 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
18560 when Decimal_Fixed_Point_Kind =>
18561 Constrain_Decimal (Def_Id, S);
18563 when Enumeration_Kind =>
18564 Constrain_Enumeration (Def_Id, S);
18566 when Ordinary_Fixed_Point_Kind =>
18567 Constrain_Ordinary_Fixed (Def_Id, S);
18570 Constrain_Float (Def_Id, S);
18572 when Integer_Kind =>
18573 Constrain_Integer (Def_Id, S);
18575 when E_Record_Type |
18578 E_Incomplete_Type =>
18579 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
18581 if Ekind (Def_Id) = E_Incomplete_Type then
18582 Set_Private_Dependents (Def_Id, New_Elmt_List);
18585 when Private_Kind =>
18586 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
18587 Set_Private_Dependents (Def_Id, New_Elmt_List);
18589 -- In case of an invalid constraint prevent further processing
18590 -- since the type constructed is missing expected fields.
18592 if Etype (Def_Id) = Any_Type then
18596 -- If the full view is that of a task with discriminants,
18597 -- we must constrain both the concurrent type and its
18598 -- corresponding record type. Otherwise we will just propagate
18599 -- the constraint to the full view, if available.
18601 if Present (Full_View (Subtype_Mark_Id))
18602 and then Has_Discriminants (Subtype_Mark_Id)
18603 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
18606 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
18608 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
18609 Constrain_Concurrent (Full_View_Id, S,
18610 Related_Nod, Related_Id, Suffix);
18611 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
18612 Set_Full_View (Def_Id, Full_View_Id);
18614 -- Introduce an explicit reference to the private subtype,
18615 -- to prevent scope anomalies in gigi if first use appears
18616 -- in a nested context, e.g. a later function body.
18617 -- Should this be generated in other contexts than a full
18618 -- type declaration?
18620 if Is_Itype (Def_Id)
18622 Nkind (Parent (P)) = N_Full_Type_Declaration
18624 Build_Itype_Reference (Def_Id, Parent (P));
18628 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
18631 when Concurrent_Kind =>
18632 Constrain_Concurrent (Def_Id, S,
18633 Related_Nod, Related_Id, Suffix);
18636 Error_Msg_N ("invalid subtype mark in subtype indication", S);
18639 -- Size and Convention are always inherited from the base type
18641 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
18642 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
18646 end Process_Subtype;
18648 ---------------------------------------
18649 -- Check_Anonymous_Access_Components --
18650 ---------------------------------------
18652 procedure Check_Anonymous_Access_Components
18653 (Typ_Decl : Node_Id;
18656 Comp_List : Node_Id)
18658 Loc : constant Source_Ptr := Sloc (Typ_Decl);
18659 Anon_Access : Entity_Id;
18662 Comp_Def : Node_Id;
18664 Type_Def : Node_Id;
18666 procedure Build_Incomplete_Type_Declaration;
18667 -- If the record type contains components that include an access to the
18668 -- current record, then create an incomplete type declaration for the
18669 -- record, to be used as the designated type of the anonymous access.
18670 -- This is done only once, and only if there is no previous partial
18671 -- view of the type.
18673 function Designates_T (Subt : Node_Id) return Boolean;
18674 -- Check whether a node designates the enclosing record type, or 'Class
18677 function Mentions_T (Acc_Def : Node_Id) return Boolean;
18678 -- Check whether an access definition includes a reference to
18679 -- the enclosing record type. The reference can be a subtype mark
18680 -- in the access definition itself, a 'Class attribute reference, or
18681 -- recursively a reference appearing in a parameter specification
18682 -- or result definition of an access_to_subprogram definition.
18684 --------------------------------------
18685 -- Build_Incomplete_Type_Declaration --
18686 --------------------------------------
18688 procedure Build_Incomplete_Type_Declaration is
18693 -- Is_Tagged indicates whether the type is tagged. It is tagged if
18694 -- it's "is new ... with record" or else "is tagged record ...".
18696 Is_Tagged : constant Boolean :=
18697 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
18700 (Record_Extension_Part (Type_Definition (Typ_Decl))))
18702 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
18703 and then Tagged_Present (Type_Definition (Typ_Decl)));
18706 -- If there is a previous partial view, no need to create a new one
18707 -- If the partial view, given by Prev, is incomplete, If Prev is
18708 -- a private declaration, full declaration is flagged accordingly.
18710 if Prev /= Typ then
18712 Make_Class_Wide_Type (Prev);
18713 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
18714 Set_Etype (Class_Wide_Type (Typ), Typ);
18719 elsif Has_Private_Declaration (Typ) then
18721 -- If we refer to T'Class inside T, and T is the completion of a
18722 -- private type, then we need to make sure the class-wide type
18726 Make_Class_Wide_Type (Typ);
18731 -- If there was a previous anonymous access type, the incomplete
18732 -- type declaration will have been created already.
18734 elsif Present (Current_Entity (Typ))
18735 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
18736 and then Full_View (Current_Entity (Typ)) = Typ
18739 and then Comes_From_Source (Current_Entity (Typ))
18740 and then not Is_Tagged_Type (Current_Entity (Typ))
18742 Make_Class_Wide_Type (Typ);
18744 ("incomplete view of tagged type should be declared tagged?",
18745 Parent (Current_Entity (Typ)));
18750 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
18751 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
18753 -- Type has already been inserted into the current scope. Remove
18754 -- it, and add incomplete declaration for type, so that subsequent
18755 -- anonymous access types can use it. The entity is unchained from
18756 -- the homonym list and from immediate visibility. After analysis,
18757 -- the entity in the incomplete declaration becomes immediately
18758 -- visible in the record declaration that follows.
18760 H := Current_Entity (Typ);
18763 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
18766 and then Homonym (H) /= Typ
18768 H := Homonym (Typ);
18771 Set_Homonym (H, Homonym (Typ));
18774 Insert_Before (Typ_Decl, Decl);
18776 Set_Full_View (Inc_T, Typ);
18780 -- Create a common class-wide type for both views, and set the
18781 -- Etype of the class-wide type to the full view.
18783 Make_Class_Wide_Type (Inc_T);
18784 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
18785 Set_Etype (Class_Wide_Type (Typ), Typ);
18788 end Build_Incomplete_Type_Declaration;
18794 function Designates_T (Subt : Node_Id) return Boolean is
18795 Type_Id : constant Name_Id := Chars (Typ);
18797 function Names_T (Nam : Node_Id) return Boolean;
18798 -- The record type has not been introduced in the current scope
18799 -- yet, so we must examine the name of the type itself, either
18800 -- an identifier T, or an expanded name of the form P.T, where
18801 -- P denotes the current scope.
18807 function Names_T (Nam : Node_Id) return Boolean is
18809 if Nkind (Nam) = N_Identifier then
18810 return Chars (Nam) = Type_Id;
18812 elsif Nkind (Nam) = N_Selected_Component then
18813 if Chars (Selector_Name (Nam)) = Type_Id then
18814 if Nkind (Prefix (Nam)) = N_Identifier then
18815 return Chars (Prefix (Nam)) = Chars (Current_Scope);
18817 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
18818 return Chars (Selector_Name (Prefix (Nam))) =
18819 Chars (Current_Scope);
18833 -- Start of processing for Designates_T
18836 if Nkind (Subt) = N_Identifier then
18837 return Chars (Subt) = Type_Id;
18839 -- Reference can be through an expanded name which has not been
18840 -- analyzed yet, and which designates enclosing scopes.
18842 elsif Nkind (Subt) = N_Selected_Component then
18843 if Names_T (Subt) then
18846 -- Otherwise it must denote an entity that is already visible.
18847 -- The access definition may name a subtype of the enclosing
18848 -- type, if there is a previous incomplete declaration for it.
18851 Find_Selected_Component (Subt);
18853 Is_Entity_Name (Subt)
18854 and then Scope (Entity (Subt)) = Current_Scope
18856 (Chars (Base_Type (Entity (Subt))) = Type_Id
18858 (Is_Class_Wide_Type (Entity (Subt))
18860 Chars (Etype (Base_Type (Entity (Subt)))) =
18864 -- A reference to the current type may appear as the prefix of
18865 -- a 'Class attribute.
18867 elsif Nkind (Subt) = N_Attribute_Reference
18868 and then Attribute_Name (Subt) = Name_Class
18870 return Names_T (Prefix (Subt));
18881 function Mentions_T (Acc_Def : Node_Id) return Boolean is
18882 Param_Spec : Node_Id;
18884 Acc_Subprg : constant Node_Id :=
18885 Access_To_Subprogram_Definition (Acc_Def);
18888 if No (Acc_Subprg) then
18889 return Designates_T (Subtype_Mark (Acc_Def));
18892 -- Component is an access_to_subprogram: examine its formals,
18893 -- and result definition in the case of an access_to_function.
18895 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
18896 while Present (Param_Spec) loop
18897 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
18898 and then Mentions_T (Parameter_Type (Param_Spec))
18902 elsif Designates_T (Parameter_Type (Param_Spec)) then
18909 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
18910 if Nkind (Result_Definition (Acc_Subprg)) =
18911 N_Access_Definition
18913 return Mentions_T (Result_Definition (Acc_Subprg));
18915 return Designates_T (Result_Definition (Acc_Subprg));
18922 -- Start of processing for Check_Anonymous_Access_Components
18925 if No (Comp_List) then
18929 Comp := First (Component_Items (Comp_List));
18930 while Present (Comp) loop
18931 if Nkind (Comp) = N_Component_Declaration
18933 (Access_Definition (Component_Definition (Comp)))
18935 Mentions_T (Access_Definition (Component_Definition (Comp)))
18937 Comp_Def := Component_Definition (Comp);
18939 Access_To_Subprogram_Definition
18940 (Access_Definition (Comp_Def));
18942 Build_Incomplete_Type_Declaration;
18943 Anon_Access := Make_Temporary (Loc, 'S');
18945 -- Create a declaration for the anonymous access type: either
18946 -- an access_to_object or an access_to_subprogram.
18948 if Present (Acc_Def) then
18949 if Nkind (Acc_Def) = N_Access_Function_Definition then
18951 Make_Access_Function_Definition (Loc,
18952 Parameter_Specifications =>
18953 Parameter_Specifications (Acc_Def),
18954 Result_Definition => Result_Definition (Acc_Def));
18957 Make_Access_Procedure_Definition (Loc,
18958 Parameter_Specifications =>
18959 Parameter_Specifications (Acc_Def));
18964 Make_Access_To_Object_Definition (Loc,
18965 Subtype_Indication =>
18968 (Access_Definition (Comp_Def))));
18970 Set_Constant_Present
18971 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
18973 (Type_Def, All_Present (Access_Definition (Comp_Def)));
18976 Set_Null_Exclusion_Present
18978 Null_Exclusion_Present (Access_Definition (Comp_Def)));
18981 Make_Full_Type_Declaration (Loc,
18982 Defining_Identifier => Anon_Access,
18983 Type_Definition => Type_Def);
18985 Insert_Before (Typ_Decl, Decl);
18988 -- If an access to subprogram, create the extra formals
18990 if Present (Acc_Def) then
18991 Create_Extra_Formals (Designated_Type (Anon_Access));
18993 -- If an access to object, preserve entity of designated type,
18994 -- for ASIS use, before rewriting the component definition.
19001 Desig := Entity (Subtype_Indication (Type_Def));
19003 -- If the access definition is to the current record,
19004 -- the visible entity at this point is an incomplete
19005 -- type. Retrieve the full view to simplify ASIS queries
19007 if Ekind (Desig) = E_Incomplete_Type then
19008 Desig := Full_View (Desig);
19012 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
19017 Make_Component_Definition (Loc,
19018 Subtype_Indication =>
19019 New_Occurrence_Of (Anon_Access, Loc)));
19021 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
19022 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
19024 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
19027 Set_Is_Local_Anonymous_Access (Anon_Access);
19033 if Present (Variant_Part (Comp_List)) then
19037 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
19038 while Present (V) loop
19039 Check_Anonymous_Access_Components
19040 (Typ_Decl, Typ, Prev, Component_List (V));
19041 Next_Non_Pragma (V);
19045 end Check_Anonymous_Access_Components;
19047 --------------------------------
19048 -- Preanalyze_Spec_Expression --
19049 --------------------------------
19051 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
19052 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
19054 In_Spec_Expression := True;
19055 Preanalyze_And_Resolve (N, T);
19056 In_Spec_Expression := Save_In_Spec_Expression;
19057 end Preanalyze_Spec_Expression;
19059 -----------------------------
19060 -- Record_Type_Declaration --
19061 -----------------------------
19063 procedure Record_Type_Declaration
19068 Def : constant Node_Id := Type_Definition (N);
19069 Is_Tagged : Boolean;
19070 Tag_Comp : Entity_Id;
19073 -- These flags must be initialized before calling Process_Discriminants
19074 -- because this routine makes use of them.
19076 Set_Ekind (T, E_Record_Type);
19078 Init_Size_Align (T);
19079 Set_Interfaces (T, No_Elist);
19080 Set_Stored_Constraint (T, No_Elist);
19084 if Ada_Version < Ada_2005
19085 or else not Interface_Present (Def)
19087 if Limited_Present (Def) then
19088 Check_SPARK_Restriction ("limited is not allowed", N);
19091 if Abstract_Present (Def) then
19092 Check_SPARK_Restriction ("abstract is not allowed", N);
19095 -- The flag Is_Tagged_Type might have already been set by
19096 -- Find_Type_Name if it detected an error for declaration T. This
19097 -- arises in the case of private tagged types where the full view
19098 -- omits the word tagged.
19101 Tagged_Present (Def)
19102 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
19104 Set_Is_Tagged_Type (T, Is_Tagged);
19105 Set_Is_Limited_Record (T, Limited_Present (Def));
19107 -- Type is abstract if full declaration carries keyword, or if
19108 -- previous partial view did.
19110 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
19111 or else Abstract_Present (Def));
19114 Check_SPARK_Restriction ("interface is not allowed", N);
19117 Analyze_Interface_Declaration (T, Def);
19119 if Present (Discriminant_Specifications (N)) then
19121 ("interface types cannot have discriminants",
19122 Defining_Identifier
19123 (First (Discriminant_Specifications (N))));
19127 -- First pass: if there are self-referential access components,
19128 -- create the required anonymous access type declarations, and if
19129 -- need be an incomplete type declaration for T itself.
19131 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
19133 if Ada_Version >= Ada_2005
19134 and then Present (Interface_List (Def))
19136 Check_Interfaces (N, Def);
19139 Ifaces_List : Elist_Id;
19142 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
19143 -- already in the parents.
19147 Ifaces_List => Ifaces_List,
19148 Exclude_Parents => True);
19150 Set_Interfaces (T, Ifaces_List);
19154 -- Records constitute a scope for the component declarations within.
19155 -- The scope is created prior to the processing of these declarations.
19156 -- Discriminants are processed first, so that they are visible when
19157 -- processing the other components. The Ekind of the record type itself
19158 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
19160 -- Enter record scope
19164 -- If an incomplete or private type declaration was already given for
19165 -- the type, then this scope already exists, and the discriminants have
19166 -- been declared within. We must verify that the full declaration
19167 -- matches the incomplete one.
19169 Check_Or_Process_Discriminants (N, T, Prev);
19171 Set_Is_Constrained (T, not Has_Discriminants (T));
19172 Set_Has_Delayed_Freeze (T, True);
19174 -- For tagged types add a manually analyzed component corresponding
19175 -- to the component _tag, the corresponding piece of tree will be
19176 -- expanded as part of the freezing actions if it is not a CPP_Class.
19180 -- Do not add the tag unless we are in expansion mode
19182 if Expander_Active then
19183 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
19184 Enter_Name (Tag_Comp);
19186 Set_Ekind (Tag_Comp, E_Component);
19187 Set_Is_Tag (Tag_Comp);
19188 Set_Is_Aliased (Tag_Comp);
19189 Set_Etype (Tag_Comp, RTE (RE_Tag));
19190 Set_DT_Entry_Count (Tag_Comp, No_Uint);
19191 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
19192 Init_Component_Location (Tag_Comp);
19194 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
19195 -- implemented interfaces.
19197 if Has_Interfaces (T) then
19198 Add_Interface_Tag_Components (N, T);
19202 Make_Class_Wide_Type (T);
19203 Set_Direct_Primitive_Operations (T, New_Elmt_List);
19206 -- We must suppress range checks when processing record components in
19207 -- the presence of discriminants, since we don't want spurious checks to
19208 -- be generated during their analysis, but Suppress_Range_Checks flags
19209 -- must be reset the after processing the record definition.
19211 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
19212 -- couldn't we just use the normal range check suppression method here.
19213 -- That would seem cleaner ???
19215 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
19216 Set_Kill_Range_Checks (T, True);
19217 Record_Type_Definition (Def, Prev);
19218 Set_Kill_Range_Checks (T, False);
19220 Record_Type_Definition (Def, Prev);
19223 -- Exit from record scope
19227 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
19228 -- the implemented interfaces and associate them an aliased entity.
19231 and then not Is_Empty_List (Interface_List (Def))
19233 Derive_Progenitor_Subprograms (T, T);
19235 end Record_Type_Declaration;
19237 ----------------------------
19238 -- Record_Type_Definition --
19239 ----------------------------
19241 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
19242 Component : Entity_Id;
19243 Ctrl_Components : Boolean := False;
19244 Final_Storage_Only : Boolean;
19248 if Ekind (Prev_T) = E_Incomplete_Type then
19249 T := Full_View (Prev_T);
19254 -- In SPARK, tagged types and type extensions may only be declared in
19255 -- the specification of library unit packages.
19257 if Present (Def) and then Is_Tagged_Type (T) then
19263 if Nkind (Parent (Def)) = N_Full_Type_Declaration then
19264 Typ := Parent (Def);
19267 (Nkind (Parent (Def)) = N_Derived_Type_Definition);
19268 Typ := Parent (Parent (Def));
19271 Ctxt := Parent (Typ);
19273 if Nkind (Ctxt) = N_Package_Body
19274 and then Nkind (Parent (Ctxt)) = N_Compilation_Unit
19276 Check_SPARK_Restriction
19277 ("type should be defined in package specification", Typ);
19279 elsif Nkind (Ctxt) /= N_Package_Specification
19280 or else Nkind (Parent (Parent (Ctxt))) /= N_Compilation_Unit
19282 Check_SPARK_Restriction
19283 ("type should be defined in library unit package", Typ);
19288 Final_Storage_Only := not Is_Controlled (T);
19290 -- Ada 2005: check whether an explicit Limited is present in a derived
19291 -- type declaration.
19293 if Nkind (Parent (Def)) = N_Derived_Type_Definition
19294 and then Limited_Present (Parent (Def))
19296 Set_Is_Limited_Record (T);
19299 -- If the component list of a record type is defined by the reserved
19300 -- word null and there is no discriminant part, then the record type has
19301 -- no components and all records of the type are null records (RM 3.7)
19302 -- This procedure is also called to process the extension part of a
19303 -- record extension, in which case the current scope may have inherited
19307 or else No (Component_List (Def))
19308 or else Null_Present (Component_List (Def))
19310 if not Is_Tagged_Type (T) then
19311 Check_SPARK_Restriction ("non-tagged record cannot be null", Def);
19315 Analyze_Declarations (Component_Items (Component_List (Def)));
19317 if Present (Variant_Part (Component_List (Def))) then
19318 Check_SPARK_Restriction ("variant part is not allowed", Def);
19319 Analyze (Variant_Part (Component_List (Def)));
19323 -- After completing the semantic analysis of the record definition,
19324 -- record components, both new and inherited, are accessible. Set their
19325 -- kind accordingly. Exclude malformed itypes from illegal declarations,
19326 -- whose Ekind may be void.
19328 Component := First_Entity (Current_Scope);
19329 while Present (Component) loop
19330 if Ekind (Component) = E_Void
19331 and then not Is_Itype (Component)
19333 Set_Ekind (Component, E_Component);
19334 Init_Component_Location (Component);
19337 if Has_Task (Etype (Component)) then
19341 if Ekind (Component) /= E_Component then
19344 -- Do not set Has_Controlled_Component on a class-wide equivalent
19345 -- type. See Make_CW_Equivalent_Type.
19347 elsif not Is_Class_Wide_Equivalent_Type (T)
19348 and then (Has_Controlled_Component (Etype (Component))
19349 or else (Chars (Component) /= Name_uParent
19350 and then Is_Controlled (Etype (Component))))
19352 Set_Has_Controlled_Component (T, True);
19353 Final_Storage_Only :=
19355 and then Finalize_Storage_Only (Etype (Component));
19356 Ctrl_Components := True;
19359 Next_Entity (Component);
19362 -- A Type is Finalize_Storage_Only only if all its controlled components
19365 if Ctrl_Components then
19366 Set_Finalize_Storage_Only (T, Final_Storage_Only);
19369 -- Place reference to end record on the proper entity, which may
19370 -- be a partial view.
19372 if Present (Def) then
19373 Process_End_Label (Def, 'e', Prev_T);
19375 end Record_Type_Definition;
19377 ------------------------
19378 -- Replace_Components --
19379 ------------------------
19381 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
19382 function Process (N : Node_Id) return Traverse_Result;
19388 function Process (N : Node_Id) return Traverse_Result is
19392 if Nkind (N) = N_Discriminant_Specification then
19393 Comp := First_Discriminant (Typ);
19394 while Present (Comp) loop
19395 if Chars (Comp) = Chars (Defining_Identifier (N)) then
19396 Set_Defining_Identifier (N, Comp);
19400 Next_Discriminant (Comp);
19403 elsif Nkind (N) = N_Component_Declaration then
19404 Comp := First_Component (Typ);
19405 while Present (Comp) loop
19406 if Chars (Comp) = Chars (Defining_Identifier (N)) then
19407 Set_Defining_Identifier (N, Comp);
19411 Next_Component (Comp);
19418 procedure Replace is new Traverse_Proc (Process);
19420 -- Start of processing for Replace_Components
19424 end Replace_Components;
19426 -------------------------------
19427 -- Set_Completion_Referenced --
19428 -------------------------------
19430 procedure Set_Completion_Referenced (E : Entity_Id) is
19432 -- If in main unit, mark entity that is a completion as referenced,
19433 -- warnings go on the partial view when needed.
19435 if In_Extended_Main_Source_Unit (E) then
19436 Set_Referenced (E);
19438 end Set_Completion_Referenced;
19440 ---------------------
19441 -- Set_Fixed_Range --
19442 ---------------------
19444 -- The range for fixed-point types is complicated by the fact that we
19445 -- do not know the exact end points at the time of the declaration. This
19446 -- is true for three reasons:
19448 -- A size clause may affect the fudging of the end-points
19449 -- A small clause may affect the values of the end-points
19450 -- We try to include the end-points if it does not affect the size
19452 -- This means that the actual end-points must be established at the point
19453 -- when the type is frozen. Meanwhile, we first narrow the range as
19454 -- permitted (so that it will fit if necessary in a small specified size),
19455 -- and then build a range subtree with these narrowed bounds.
19457 -- Set_Fixed_Range constructs the range from real literal values, and sets
19458 -- the range as the Scalar_Range of the given fixed-point type entity.
19460 -- The parent of this range is set to point to the entity so that it is
19461 -- properly hooked into the tree (unlike normal Scalar_Range entries for
19462 -- other scalar types, which are just pointers to the range in the
19463 -- original tree, this would otherwise be an orphan).
19465 -- The tree is left unanalyzed. When the type is frozen, the processing
19466 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
19467 -- analyzed, and uses this as an indication that it should complete
19468 -- work on the range (it will know the final small and size values).
19470 procedure Set_Fixed_Range
19476 S : constant Node_Id :=
19478 Low_Bound => Make_Real_Literal (Loc, Lo),
19479 High_Bound => Make_Real_Literal (Loc, Hi));
19481 Set_Scalar_Range (E, S);
19483 end Set_Fixed_Range;
19485 ----------------------------------
19486 -- Set_Scalar_Range_For_Subtype --
19487 ----------------------------------
19489 procedure Set_Scalar_Range_For_Subtype
19490 (Def_Id : Entity_Id;
19494 Kind : constant Entity_Kind := Ekind (Def_Id);
19497 -- Defend against previous error
19499 if Nkind (R) = N_Error then
19503 Set_Scalar_Range (Def_Id, R);
19505 -- We need to link the range into the tree before resolving it so
19506 -- that types that are referenced, including importantly the subtype
19507 -- itself, are properly frozen (Freeze_Expression requires that the
19508 -- expression be properly linked into the tree). Of course if it is
19509 -- already linked in, then we do not disturb the current link.
19511 if No (Parent (R)) then
19512 Set_Parent (R, Def_Id);
19515 -- Reset the kind of the subtype during analysis of the range, to
19516 -- catch possible premature use in the bounds themselves.
19518 Set_Ekind (Def_Id, E_Void);
19519 Process_Range_Expr_In_Decl (R, Subt);
19520 Set_Ekind (Def_Id, Kind);
19522 -- In ALFA, all subtypes should have a static range
19524 if Nkind (R) = N_Range
19525 and then not Is_Static_Range (R)
19527 Set_Is_In_ALFA (Def_Id, False);
19529 end Set_Scalar_Range_For_Subtype;
19531 --------------------------------------------------------
19532 -- Set_Stored_Constraint_From_Discriminant_Constraint --
19533 --------------------------------------------------------
19535 procedure Set_Stored_Constraint_From_Discriminant_Constraint
19539 -- Make sure set if encountered during Expand_To_Stored_Constraint
19541 Set_Stored_Constraint (E, No_Elist);
19543 -- Give it the right value
19545 if Is_Constrained (E) and then Has_Discriminants (E) then
19546 Set_Stored_Constraint (E,
19547 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
19549 end Set_Stored_Constraint_From_Discriminant_Constraint;
19551 -------------------------------------
19552 -- Signed_Integer_Type_Declaration --
19553 -------------------------------------
19555 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
19556 Implicit_Base : Entity_Id;
19557 Base_Typ : Entity_Id;
19560 Errs : Boolean := False;
19564 function Can_Derive_From (E : Entity_Id) return Boolean;
19565 -- Determine whether given bounds allow derivation from specified type
19567 procedure Check_Bound (Expr : Node_Id);
19568 -- Check bound to make sure it is integral and static. If not, post
19569 -- appropriate error message and set Errs flag
19571 ---------------------
19572 -- Can_Derive_From --
19573 ---------------------
19575 -- Note we check both bounds against both end values, to deal with
19576 -- strange types like ones with a range of 0 .. -12341234.
19578 function Can_Derive_From (E : Entity_Id) return Boolean is
19579 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
19580 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
19582 return Lo <= Lo_Val and then Lo_Val <= Hi
19584 Lo <= Hi_Val and then Hi_Val <= Hi;
19585 end Can_Derive_From;
19591 procedure Check_Bound (Expr : Node_Id) is
19593 -- If a range constraint is used as an integer type definition, each
19594 -- bound of the range must be defined by a static expression of some
19595 -- integer type, but the two bounds need not have the same integer
19596 -- type (Negative bounds are allowed.) (RM 3.5.4)
19598 if not Is_Integer_Type (Etype (Expr)) then
19600 ("integer type definition bounds must be of integer type", Expr);
19603 elsif not Is_OK_Static_Expression (Expr) then
19604 Flag_Non_Static_Expr
19605 ("non-static expression used for integer type bound!", Expr);
19608 -- The bounds are folded into literals, and we set their type to be
19609 -- universal, to avoid typing difficulties: we cannot set the type
19610 -- of the literal to the new type, because this would be a forward
19611 -- reference for the back end, and if the original type is user-
19612 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
19615 if Is_Entity_Name (Expr) then
19616 Fold_Uint (Expr, Expr_Value (Expr), True);
19619 Set_Etype (Expr, Universal_Integer);
19623 -- Start of processing for Signed_Integer_Type_Declaration
19626 -- Create an anonymous base type
19629 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
19631 -- Analyze and check the bounds, they can be of any integer type
19633 Lo := Low_Bound (Def);
19634 Hi := High_Bound (Def);
19636 -- Arbitrarily use Integer as the type if either bound had an error
19638 if Hi = Error or else Lo = Error then
19639 Base_Typ := Any_Integer;
19640 Set_Error_Posted (T, True);
19642 -- Here both bounds are OK expressions
19645 Analyze_And_Resolve (Lo, Any_Integer);
19646 Analyze_And_Resolve (Hi, Any_Integer);
19652 Hi := Type_High_Bound (Standard_Long_Long_Integer);
19653 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
19656 -- Find type to derive from
19658 Lo_Val := Expr_Value (Lo);
19659 Hi_Val := Expr_Value (Hi);
19661 if Can_Derive_From (Standard_Short_Short_Integer) then
19662 Base_Typ := Base_Type (Standard_Short_Short_Integer);
19664 elsif Can_Derive_From (Standard_Short_Integer) then
19665 Base_Typ := Base_Type (Standard_Short_Integer);
19667 elsif Can_Derive_From (Standard_Integer) then
19668 Base_Typ := Base_Type (Standard_Integer);
19670 elsif Can_Derive_From (Standard_Long_Integer) then
19671 Base_Typ := Base_Type (Standard_Long_Integer);
19673 elsif Can_Derive_From (Standard_Long_Long_Integer) then
19674 Base_Typ := Base_Type (Standard_Long_Long_Integer);
19677 Base_Typ := Base_Type (Standard_Long_Long_Integer);
19678 Error_Msg_N ("integer type definition bounds out of range", Def);
19679 Hi := Type_High_Bound (Standard_Long_Long_Integer);
19680 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
19684 -- Complete both implicit base and declared first subtype entities
19686 Set_Etype (Implicit_Base, Base_Typ);
19687 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
19688 Set_Size_Info (Implicit_Base, (Base_Typ));
19689 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
19690 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
19692 Set_Ekind (T, E_Signed_Integer_Subtype);
19693 Set_Etype (T, Implicit_Base);
19695 Set_Size_Info (T, (Implicit_Base));
19696 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
19697 Set_Scalar_Range (T, Def);
19698 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
19699 Set_Is_Constrained (T);
19700 Set_Is_In_ALFA (T);
19701 end Signed_Integer_Type_Declaration;