1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2016, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Aspects; use Aspects;
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Contracts; use Contracts;
30 with Debug; use Debug;
31 with Elists; use Elists;
32 with Einfo; use Einfo;
33 with Errout; use Errout;
34 with Eval_Fat; use Eval_Fat;
35 with Exp_Ch3; use Exp_Ch3;
36 with Exp_Ch9; use Exp_Ch9;
37 with Exp_Disp; use Exp_Disp;
38 with Exp_Dist; use Exp_Dist;
39 with Exp_Tss; use Exp_Tss;
40 with Exp_Util; use Exp_Util;
41 with Fname; use Fname;
42 with Freeze; use Freeze;
43 with Ghost; use Ghost;
44 with Itypes; use Itypes;
45 with Layout; use Layout;
47 with Lib.Xref; use Lib.Xref;
48 with Namet; use Namet;
49 with Nmake; use Nmake;
51 with Restrict; use Restrict;
52 with Rident; use Rident;
53 with Rtsfind; use Rtsfind;
55 with Sem_Aux; use Sem_Aux;
56 with Sem_Case; use Sem_Case;
57 with Sem_Cat; use Sem_Cat;
58 with Sem_Ch6; use Sem_Ch6;
59 with Sem_Ch7; use Sem_Ch7;
60 with Sem_Ch8; use Sem_Ch8;
61 with Sem_Ch13; use Sem_Ch13;
62 with Sem_Dim; use Sem_Dim;
63 with Sem_Disp; use Sem_Disp;
64 with Sem_Dist; use Sem_Dist;
65 with Sem_Elim; use Sem_Elim;
66 with Sem_Eval; use Sem_Eval;
67 with Sem_Mech; use Sem_Mech;
68 with Sem_Res; use Sem_Res;
69 with Sem_Smem; use Sem_Smem;
70 with Sem_Type; use Sem_Type;
71 with Sem_Util; use Sem_Util;
72 with Sem_Warn; use Sem_Warn;
73 with Stand; use Stand;
74 with Sinfo; use Sinfo;
75 with Sinput; use Sinput;
76 with Snames; use Snames;
77 with Targparm; use Targparm;
78 with Tbuild; use Tbuild;
79 with Ttypes; use Ttypes;
80 with Uintp; use Uintp;
81 with Urealp; use Urealp;
83 package body Sem_Ch3 is
85 -----------------------
86 -- Local Subprograms --
87 -----------------------
89 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id);
90 -- Ada 2005 (AI-251): Add the tag components corresponding to all the
91 -- abstract interface types implemented by a record type or a derived
94 procedure Build_Derived_Type
96 Parent_Type : Entity_Id;
97 Derived_Type : Entity_Id;
98 Is_Completion : Boolean;
99 Derive_Subps : Boolean := True);
100 -- Create and decorate a Derived_Type given the Parent_Type entity. N is
101 -- the N_Full_Type_Declaration node containing the derived type definition.
102 -- Parent_Type is the entity for the parent type in the derived type
103 -- definition and Derived_Type the actual derived type. Is_Completion must
104 -- be set to False if Derived_Type is the N_Defining_Identifier node in N
105 -- (i.e. Derived_Type = Defining_Identifier (N)). In this case N is not the
106 -- completion of a private type declaration. If Is_Completion is set to
107 -- True, N is the completion of a private type declaration and Derived_Type
108 -- is different from the defining identifier inside N (i.e. Derived_Type /=
109 -- Defining_Identifier (N)). Derive_Subps indicates whether the parent
110 -- subprograms should be derived. The only case where this parameter is
111 -- False is when Build_Derived_Type is recursively called to process an
112 -- implicit derived full type for a type derived from a private type (in
113 -- that case the subprograms must only be derived for the private view of
116 -- ??? These flags need a bit of re-examination and re-documentation:
117 -- ??? are they both necessary (both seem related to the recursion)?
119 procedure Build_Derived_Access_Type
121 Parent_Type : Entity_Id;
122 Derived_Type : Entity_Id);
123 -- Subsidiary procedure to Build_Derived_Type. For a derived access type,
124 -- create an implicit base if the parent type is constrained or if the
125 -- subtype indication has a constraint.
127 procedure Build_Derived_Array_Type
129 Parent_Type : Entity_Id;
130 Derived_Type : Entity_Id);
131 -- Subsidiary procedure to Build_Derived_Type. For a derived array type,
132 -- create an implicit base if the parent type is constrained or if the
133 -- subtype indication has a constraint.
135 procedure Build_Derived_Concurrent_Type
137 Parent_Type : Entity_Id;
138 Derived_Type : Entity_Id);
139 -- Subsidiary procedure to Build_Derived_Type. For a derived task or
140 -- protected type, inherit entries and protected subprograms, check
141 -- legality of discriminant constraints if any.
143 procedure Build_Derived_Enumeration_Type
145 Parent_Type : Entity_Id;
146 Derived_Type : Entity_Id);
147 -- Subsidiary procedure to Build_Derived_Type. For a derived enumeration
148 -- type, we must create a new list of literals. Types derived from
149 -- Character and [Wide_]Wide_Character are special-cased.
151 procedure Build_Derived_Numeric_Type
153 Parent_Type : Entity_Id;
154 Derived_Type : Entity_Id);
155 -- Subsidiary procedure to Build_Derived_Type. For numeric types, create
156 -- an anonymous base type, and propagate constraint to subtype if needed.
158 procedure Build_Derived_Private_Type
160 Parent_Type : Entity_Id;
161 Derived_Type : Entity_Id;
162 Is_Completion : Boolean;
163 Derive_Subps : Boolean := True);
164 -- Subsidiary procedure to Build_Derived_Type. This procedure is complex
165 -- because the parent may or may not have a completion, and the derivation
166 -- may itself be a completion.
168 procedure Build_Derived_Record_Type
170 Parent_Type : Entity_Id;
171 Derived_Type : Entity_Id;
172 Derive_Subps : Boolean := True);
173 -- Subsidiary procedure used for tagged and untagged record types
174 -- by Build_Derived_Type and Analyze_Private_Extension_Declaration.
175 -- All parameters are as in Build_Derived_Type except that N, in
176 -- addition to being an N_Full_Type_Declaration node, can also be an
177 -- N_Private_Extension_Declaration node. See the definition of this routine
178 -- for much more info. Derive_Subps indicates whether subprograms should be
179 -- derived from the parent type. The only case where Derive_Subps is False
180 -- is for an implicit derived full type for a type derived from a private
181 -- type (see Build_Derived_Type).
183 procedure Build_Discriminal (Discrim : Entity_Id);
184 -- Create the discriminal corresponding to discriminant Discrim, that is
185 -- the parameter corresponding to Discrim to be used in initialization
186 -- procedures for the type where Discrim is a discriminant. Discriminals
187 -- are not used during semantic analysis, and are not fully defined
188 -- entities until expansion. Thus they are not given a scope until
189 -- initialization procedures are built.
191 function Build_Discriminant_Constraints
194 Derived_Def : Boolean := False) return Elist_Id;
195 -- Validate discriminant constraints and return the list of the constraints
196 -- in order of discriminant declarations, where T is the discriminated
197 -- unconstrained type. Def is the N_Subtype_Indication node where the
198 -- discriminants constraints for T are specified. Derived_Def is True
199 -- when building the discriminant constraints in a derived type definition
200 -- of the form "type D (...) is new T (xxx)". In this case T is the parent
201 -- type and Def is the constraint "(xxx)" on T and this routine sets the
202 -- Corresponding_Discriminant field of the discriminants in the derived
203 -- type D to point to the corresponding discriminants in the parent type T.
205 procedure Build_Discriminated_Subtype
209 Related_Nod : Node_Id;
210 For_Access : Boolean := False);
211 -- Subsidiary procedure to Constrain_Discriminated_Type and to
212 -- Process_Incomplete_Dependents. Given
214 -- T (a possibly discriminated base type)
215 -- Def_Id (a very partially built subtype for T),
217 -- the call completes Def_Id to be the appropriate E_*_Subtype.
219 -- The Elist is the list of discriminant constraints if any (it is set
220 -- to No_Elist if T is not a discriminated type, and to an empty list if
221 -- T has discriminants but there are no discriminant constraints). The
222 -- Related_Nod is the same as Decl_Node in Create_Constrained_Components.
223 -- The For_Access says whether or not this subtype is really constraining
224 -- an access type. That is its sole purpose is the designated type of an
225 -- access type -- in which case a Private_Subtype Is_For_Access_Subtype
226 -- is built to avoid freezing T when the access subtype is frozen.
228 function Build_Scalar_Bound
231 Der_T : Entity_Id) return Node_Id;
232 -- The bounds of a derived scalar type are conversions of the bounds of
233 -- the parent type. Optimize the representation if the bounds are literals.
234 -- Needs a more complete spec--what are the parameters exactly, and what
235 -- exactly is the returned value, and how is Bound affected???
237 procedure Build_Underlying_Full_View
241 -- If the completion of a private type is itself derived from a private
242 -- type, or if the full view of a private subtype is itself private, the
243 -- back-end has no way to compute the actual size of this type. We build
244 -- an internal subtype declaration of the proper parent type to convey
245 -- this information. This extra mechanism is needed because a full
246 -- view cannot itself have a full view (it would get clobbered during
249 procedure Check_Access_Discriminant_Requires_Limited
252 -- Check the restriction that the type to which an access discriminant
253 -- belongs must be a concurrent type or a descendant of a type with
254 -- the reserved word 'limited' in its declaration.
256 procedure Check_Anonymous_Access_Components
260 Comp_List : Node_Id);
261 -- Ada 2005 AI-382: an access component in a record definition can refer to
262 -- the enclosing record, in which case it denotes the type itself, and not
263 -- the current instance of the type. We create an anonymous access type for
264 -- the component, and flag it as an access to a component, so accessibility
265 -- checks are properly performed on it. The declaration of the access type
266 -- is placed ahead of that of the record to prevent order-of-elaboration
267 -- circularity issues in Gigi. We create an incomplete type for the record
268 -- declaration, which is the designated type of the anonymous access.
270 procedure Check_Delta_Expression (E : Node_Id);
271 -- Check that the expression represented by E is suitable for use as a
272 -- delta expression, i.e. it is of real type and is static.
274 procedure Check_Digits_Expression (E : Node_Id);
275 -- Check that the expression represented by E is suitable for use as a
276 -- digits expression, i.e. it is of integer type, positive and static.
278 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id);
279 -- Validate the initialization of an object declaration. T is the required
280 -- type, and Exp is the initialization expression.
282 procedure Check_Interfaces (N : Node_Id; Def : Node_Id);
283 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
285 procedure Check_Or_Process_Discriminants
288 Prev : Entity_Id := Empty);
289 -- If N is the full declaration of the completion T of an incomplete or
290 -- private type, check its discriminants (which are already known to be
291 -- conformant with those of the partial view, see Find_Type_Name),
292 -- otherwise process them. Prev is the entity of the partial declaration,
295 procedure Check_Real_Bound (Bound : Node_Id);
296 -- Check given bound for being of real type and static. If not, post an
297 -- appropriate message, and rewrite the bound with the real literal zero.
299 procedure Constant_Redeclaration
303 -- Various checks on legality of full declaration of deferred constant.
304 -- Id is the entity for the redeclaration, N is the N_Object_Declaration,
305 -- node. The caller has not yet set any attributes of this entity.
307 function Contain_Interface
309 Ifaces : Elist_Id) return Boolean;
310 -- Ada 2005: Determine whether Iface is present in the list Ifaces
312 procedure Convert_Scalar_Bounds
314 Parent_Type : Entity_Id;
315 Derived_Type : Entity_Id;
317 -- For derived scalar types, convert the bounds in the type definition to
318 -- the derived type, and complete their analysis. Given a constraint of the
319 -- form ".. new T range Lo .. Hi", Lo and Hi are analyzed and resolved with
320 -- T'Base, the parent_type. The bounds of the derived type (the anonymous
321 -- base) are copies of Lo and Hi. Finally, the bounds of the derived
322 -- subtype are conversions of those bounds to the derived_type, so that
323 -- their typing is consistent.
325 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id);
326 -- Copies attributes from array base type T2 to array base type T1. Copies
327 -- only attributes that apply to base types, but not subtypes.
329 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id);
330 -- Copies attributes from array subtype T2 to array subtype T1. Copies
331 -- attributes that apply to both subtypes and base types.
333 procedure Create_Constrained_Components
337 Constraints : Elist_Id);
338 -- Build the list of entities for a constrained discriminated record
339 -- subtype. If a component depends on a discriminant, replace its subtype
340 -- using the discriminant values in the discriminant constraint. Subt
341 -- is the defining identifier for the subtype whose list of constrained
342 -- entities we will create. Decl_Node is the type declaration node where
343 -- we will attach all the itypes created. Typ is the base discriminated
344 -- type for the subtype Subt. Constraints is the list of discriminant
345 -- constraints for Typ.
347 function Constrain_Component_Type
349 Constrained_Typ : Entity_Id;
350 Related_Node : Node_Id;
352 Constraints : Elist_Id) return Entity_Id;
353 -- Given a discriminated base type Typ, a list of discriminant constraints,
354 -- Constraints, for Typ and a component Comp of Typ, create and return the
355 -- type corresponding to Etype (Comp) where all discriminant references
356 -- are replaced with the corresponding constraint. If Etype (Comp) contains
357 -- no discriminant references then it is returned as-is. Constrained_Typ
358 -- is the final constrained subtype to which the constrained component
359 -- belongs. Related_Node is the node where we attach all created itypes.
361 procedure Constrain_Access
362 (Def_Id : in out Entity_Id;
364 Related_Nod : Node_Id);
365 -- Apply a list of constraints to an access type. If Def_Id is empty, it is
366 -- an anonymous type created for a subtype indication. In that case it is
367 -- created in the procedure and attached to Related_Nod.
369 procedure Constrain_Array
370 (Def_Id : in out Entity_Id;
372 Related_Nod : Node_Id;
373 Related_Id : Entity_Id;
375 -- Apply a list of index constraints to an unconstrained array type. The
376 -- first parameter is the entity for the resulting subtype. A value of
377 -- Empty for Def_Id indicates that an implicit type must be created, but
378 -- creation is delayed (and must be done by this procedure) because other
379 -- subsidiary implicit types must be created first (which is why Def_Id
380 -- is an in/out parameter). The second parameter is a subtype indication
381 -- node for the constrained array to be created (e.g. something of the
382 -- form string (1 .. 10)). Related_Nod gives the place where this type
383 -- has to be inserted in the tree. The Related_Id and Suffix parameters
384 -- are used to build the associated Implicit type name.
386 procedure Constrain_Concurrent
387 (Def_Id : in out Entity_Id;
389 Related_Nod : Node_Id;
390 Related_Id : Entity_Id;
392 -- Apply list of discriminant constraints to an unconstrained concurrent
395 -- SI is the N_Subtype_Indication node containing the constraint and
396 -- the unconstrained type to constrain.
398 -- Def_Id is the entity for the resulting constrained subtype. A value
399 -- of Empty for Def_Id indicates that an implicit type must be created,
400 -- but creation is delayed (and must be done by this procedure) because
401 -- other subsidiary implicit types must be created first (which is why
402 -- Def_Id is an in/out parameter).
404 -- Related_Nod gives the place where this type has to be inserted
407 -- The last two arguments are used to create its external name if needed.
409 function Constrain_Corresponding_Record
410 (Prot_Subt : Entity_Id;
411 Corr_Rec : Entity_Id;
412 Related_Nod : Node_Id) return Entity_Id;
413 -- When constraining a protected type or task type with discriminants,
414 -- constrain the corresponding record with the same discriminant values.
416 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id);
417 -- Constrain a decimal fixed point type with a digits constraint and/or a
418 -- range constraint, and build E_Decimal_Fixed_Point_Subtype entity.
420 procedure Constrain_Discriminated_Type
423 Related_Nod : Node_Id;
424 For_Access : Boolean := False);
425 -- Process discriminant constraints of composite type. Verify that values
426 -- have been provided for all discriminants, that the original type is
427 -- unconstrained, and that the types of the supplied expressions match
428 -- the discriminant types. The first three parameters are like in routine
429 -- Constrain_Concurrent. See Build_Discriminated_Subtype for an explanation
432 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id);
433 -- Constrain an enumeration type with a range constraint. This is identical
434 -- to Constrain_Integer, but for the Ekind of the resulting subtype.
436 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id);
437 -- Constrain a floating point type with either a digits constraint
438 -- and/or a range constraint, building a E_Floating_Point_Subtype.
440 procedure Constrain_Index
443 Related_Nod : Node_Id;
444 Related_Id : Entity_Id;
447 -- Process an index constraint S in a constrained array declaration. The
448 -- constraint can be a subtype name, or a range with or without an explicit
449 -- subtype mark. The index is the corresponding index of the unconstrained
450 -- array. The Related_Id and Suffix parameters are used to build the
451 -- associated Implicit type name.
453 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id);
454 -- Build subtype of a signed or modular integer type
456 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id);
457 -- Constrain an ordinary fixed point type with a range constraint, and
458 -- build an E_Ordinary_Fixed_Point_Subtype entity.
460 procedure Copy_And_Swap (Priv, Full : Entity_Id);
461 -- Copy the Priv entity into the entity of its full declaration then swap
462 -- the two entities in such a manner that the former private type is now
463 -- seen as a full type.
465 procedure Decimal_Fixed_Point_Type_Declaration
468 -- Create a new decimal fixed point type, and apply the constraint to
469 -- obtain a subtype of this new type.
471 procedure Complete_Private_Subtype
474 Full_Base : Entity_Id;
475 Related_Nod : Node_Id);
476 -- Complete the implicit full view of a private subtype by setting the
477 -- appropriate semantic fields. If the full view of the parent is a record
478 -- type, build constrained components of subtype.
480 procedure Derive_Progenitor_Subprograms
481 (Parent_Type : Entity_Id;
482 Tagged_Type : Entity_Id);
483 -- Ada 2005 (AI-251): To complete type derivation, collect the primitive
484 -- operations of progenitors of Tagged_Type, and replace the subsidiary
485 -- subtypes with Tagged_Type, to build the specs of the inherited interface
486 -- primitives. The derived primitives are aliased to those of the
487 -- interface. This routine takes care also of transferring to the full view
488 -- subprograms associated with the partial view of Tagged_Type that cover
489 -- interface primitives.
491 procedure Derived_Standard_Character
493 Parent_Type : Entity_Id;
494 Derived_Type : Entity_Id);
495 -- Subsidiary procedure to Build_Derived_Enumeration_Type which handles
496 -- derivations from types Standard.Character and Standard.Wide_Character.
498 procedure Derived_Type_Declaration
501 Is_Completion : Boolean);
502 -- Process a derived type declaration. Build_Derived_Type is invoked
503 -- to process the actual derived type definition. Parameters N and
504 -- Is_Completion have the same meaning as in Build_Derived_Type.
505 -- T is the N_Defining_Identifier for the entity defined in the
506 -- N_Full_Type_Declaration node N, that is T is the derived type.
508 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id);
509 -- Insert each literal in symbol table, as an overloadable identifier. Each
510 -- enumeration type is mapped into a sequence of integers, and each literal
511 -- is defined as a constant with integer value. If any of the literals are
512 -- character literals, the type is a character type, which means that
513 -- strings are legal aggregates for arrays of components of the type.
515 function Expand_To_Stored_Constraint
517 Constraint : Elist_Id) return Elist_Id;
518 -- Given a constraint (i.e. a list of expressions) on the discriminants of
519 -- Typ, expand it into a constraint on the stored discriminants and return
520 -- the new list of expressions constraining the stored discriminants.
522 function Find_Type_Of_Object
524 Related_Nod : Node_Id) return Entity_Id;
525 -- Get type entity for object referenced by Obj_Def, attaching the implicit
526 -- types generated to Related_Nod.
528 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id);
529 -- Create a new float and apply the constraint to obtain subtype of it
531 function Has_Range_Constraint (N : Node_Id) return Boolean;
532 -- Given an N_Subtype_Indication node N, return True if a range constraint
533 -- is present, either directly, or as part of a digits or delta constraint.
534 -- In addition, a digits constraint in the decimal case returns True, since
535 -- it establishes a default range if no explicit range is present.
537 function Inherit_Components
539 Parent_Base : Entity_Id;
540 Derived_Base : Entity_Id;
542 Inherit_Discr : Boolean;
543 Discs : Elist_Id) return Elist_Id;
544 -- Called from Build_Derived_Record_Type to inherit the components of
545 -- Parent_Base (a base type) into the Derived_Base (the derived base type).
546 -- For more information on derived types and component inheritance please
547 -- consult the comment above the body of Build_Derived_Record_Type.
549 -- N is the original derived type declaration
551 -- Is_Tagged is set if we are dealing with tagged types
553 -- If Inherit_Discr is set, Derived_Base inherits its discriminants from
554 -- Parent_Base, otherwise no discriminants are inherited.
556 -- Discs gives the list of constraints that apply to Parent_Base in the
557 -- derived type declaration. If Discs is set to No_Elist, then we have
558 -- the following situation:
560 -- type Parent (D1..Dn : ..) is [tagged] record ...;
561 -- type Derived is new Parent [with ...];
563 -- which gets treated as
565 -- type Derived (D1..Dn : ..) is new Parent (D1,..,Dn) [with ...];
567 -- For untagged types the returned value is an association list. The list
568 -- starts from the association (Parent_Base => Derived_Base), and then it
569 -- contains a sequence of the associations of the form
571 -- (Old_Component => New_Component),
573 -- where Old_Component is the Entity_Id of a component in Parent_Base and
574 -- New_Component is the Entity_Id of the corresponding component in
575 -- Derived_Base. For untagged records, this association list is needed when
576 -- copying the record declaration for the derived base. In the tagged case
577 -- the value returned is irrelevant.
579 procedure Inherit_Predicate_Flags (Subt, Par : Entity_Id);
580 -- Propagate static and dynamic predicate flags from a parent to the
581 -- subtype in a subtype declaration with and without constraints.
583 function Is_EVF_Procedure (Subp : Entity_Id) return Boolean;
584 -- Subsidiary to Check_Abstract_Overriding and Derive_Subprogram.
585 -- Determine whether subprogram Subp is a procedure subject to pragma
586 -- Extensions_Visible with value False and has at least one controlling
587 -- parameter of mode OUT.
589 function Is_Valid_Constraint_Kind
591 Constraint_Kind : Node_Kind) return Boolean;
592 -- Returns True if it is legal to apply the given kind of constraint to the
593 -- given kind of type (index constraint to an array type, for example).
595 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id);
596 -- Create new modular type. Verify that modulus is in bounds
598 procedure New_Concatenation_Op (Typ : Entity_Id);
599 -- Create an abbreviated declaration for an operator in order to
600 -- materialize concatenation on array types.
602 procedure Ordinary_Fixed_Point_Type_Declaration
605 -- Create a new ordinary fixed point type, and apply the constraint to
606 -- obtain subtype of it.
608 procedure Prepare_Private_Subtype_Completion
610 Related_Nod : Node_Id);
611 -- Id is a subtype of some private type. Creates the full declaration
612 -- associated with Id whenever possible, i.e. when the full declaration
613 -- of the base type is already known. Records each subtype into
614 -- Private_Dependents of the base type.
616 procedure Process_Incomplete_Dependents
620 -- Process all entities that depend on an incomplete type. There include
621 -- subtypes, subprogram types that mention the incomplete type in their
622 -- profiles, and subprogram with access parameters that designate the
625 -- Inc_T is the defining identifier of an incomplete type declaration, its
626 -- Ekind is E_Incomplete_Type.
628 -- N is the corresponding N_Full_Type_Declaration for Inc_T.
630 -- Full_T is N's defining identifier.
632 -- Subtypes of incomplete types with discriminants are completed when the
633 -- parent type is. This is simpler than private subtypes, because they can
634 -- only appear in the same scope, and there is no need to exchange views.
635 -- Similarly, access_to_subprogram types may have a parameter or a return
636 -- type that is an incomplete type, and that must be replaced with the
639 -- If the full type is tagged, subprogram with access parameters that
640 -- designated the incomplete may be primitive operations of the full type,
641 -- and have to be processed accordingly.
643 procedure Process_Real_Range_Specification (Def : Node_Id);
644 -- Given the type definition for a real type, this procedure processes and
645 -- checks the real range specification of this type definition if one is
646 -- present. If errors are found, error messages are posted, and the
647 -- Real_Range_Specification of Def is reset to Empty.
649 procedure Propagate_Default_Init_Cond_Attributes
650 (From_Typ : Entity_Id;
652 Parent_To_Derivation : Boolean := False;
653 Private_To_Full_View : Boolean := False);
654 -- Subsidiary to routines Build_Derived_Type and Process_Full_View. Inherit
655 -- all attributes related to pragma Default_Initial_Condition from From_Typ
656 -- to To_Typ. Flag Parent_To_Derivation should be set when the context is
657 -- the creation of a derived type. Flag Private_To_Full_View should be set
658 -- when processing both views of a private type.
660 procedure Record_Type_Declaration
664 -- Process a record type declaration (for both untagged and tagged
665 -- records). Parameters T and N are exactly like in procedure
666 -- Derived_Type_Declaration, except that no flag Is_Completion is needed
667 -- for this routine. If this is the completion of an incomplete type
668 -- declaration, Prev is the entity of the incomplete declaration, used for
669 -- cross-referencing. Otherwise Prev = T.
671 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id);
672 -- This routine is used to process the actual record type definition (both
673 -- for untagged and tagged records). Def is a record type definition node.
674 -- This procedure analyzes the components in this record type definition.
675 -- Prev_T is the entity for the enclosing record type. It is provided so
676 -- that its Has_Task flag can be set if any of the component have Has_Task
677 -- set. If the declaration is the completion of an incomplete type
678 -- declaration, Prev_T is the original incomplete type, whose full view is
681 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id);
682 -- Subsidiary to Build_Derived_Record_Type. For untagged records, we
683 -- build a copy of the declaration tree of the parent, and we create
684 -- independently the list of components for the derived type. Semantic
685 -- information uses the component entities, but record representation
686 -- clauses are validated on the declaration tree. This procedure replaces
687 -- discriminants and components in the declaration with those that have
688 -- been created by Inherit_Components.
690 procedure Set_Fixed_Range
695 -- Build a range node with the given bounds and set it as the Scalar_Range
696 -- of the given fixed-point type entity. Loc is the source location used
697 -- for the constructed range. See body for further details.
699 procedure Set_Scalar_Range_For_Subtype
703 -- This routine is used to set the scalar range field for a subtype given
704 -- Def_Id, the entity for the subtype, and R, the range expression for the
705 -- scalar range. Subt provides the parent subtype to be used to analyze,
706 -- resolve, and check the given range.
708 procedure Set_Default_SSO (T : Entity_Id);
709 -- T is the entity for an array or record being declared. This procedure
710 -- sets the flags SSO_Set_Low_By_Default/SSO_Set_High_By_Default according
711 -- to the setting of Opt.Default_SSO.
713 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id);
714 -- Create a new signed integer entity, and apply the constraint to obtain
715 -- the required first named subtype of this type.
717 procedure Set_Stored_Constraint_From_Discriminant_Constraint
719 -- E is some record type. This routine computes E's Stored_Constraint
720 -- from its Discriminant_Constraint.
722 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id);
723 -- Check that an entity in a list of progenitors is an interface,
724 -- emit error otherwise.
726 -----------------------
727 -- Access_Definition --
728 -----------------------
730 function Access_Definition
731 (Related_Nod : Node_Id;
732 N : Node_Id) return Entity_Id
734 Anon_Type : Entity_Id;
735 Anon_Scope : Entity_Id;
736 Desig_Type : Entity_Id;
737 Enclosing_Prot_Type : Entity_Id := Empty;
740 Check_SPARK_05_Restriction ("access type is not allowed", N);
742 if Is_Entry (Current_Scope)
743 and then Is_Task_Type (Etype (Scope (Current_Scope)))
745 Error_Msg_N ("task entries cannot have access parameters", N);
749 -- Ada 2005: For an object declaration the corresponding anonymous
750 -- type is declared in the current scope.
752 -- If the access definition is the return type of another access to
753 -- function, scope is the current one, because it is the one of the
754 -- current type declaration, except for the pathological case below.
756 if Nkind_In (Related_Nod, N_Object_Declaration,
757 N_Access_Function_Definition)
759 Anon_Scope := Current_Scope;
761 -- A pathological case: function returning access functions that
762 -- return access functions, etc. Each anonymous access type created
763 -- is in the enclosing scope of the outermost function.
770 while Nkind_In (Par, N_Access_Function_Definition,
776 if Nkind (Par) = N_Function_Specification then
777 Anon_Scope := Scope (Defining_Entity (Par));
781 -- For the anonymous function result case, retrieve the scope of the
782 -- function specification's associated entity rather than using the
783 -- current scope. The current scope will be the function itself if the
784 -- formal part is currently being analyzed, but will be the parent scope
785 -- in the case of a parameterless function, and we always want to use
786 -- the function's parent scope. Finally, if the function is a child
787 -- unit, we must traverse the tree to retrieve the proper entity.
789 elsif Nkind (Related_Nod) = N_Function_Specification
790 and then Nkind (Parent (N)) /= N_Parameter_Specification
792 -- If the current scope is a protected type, the anonymous access
793 -- is associated with one of the protected operations, and must
794 -- be available in the scope that encloses the protected declaration.
795 -- Otherwise the type is in the scope enclosing the subprogram.
797 -- If the function has formals, The return type of a subprogram
798 -- declaration is analyzed in the scope of the subprogram (see
799 -- Process_Formals) and thus the protected type, if present, is
800 -- the scope of the current function scope.
802 if Ekind (Current_Scope) = E_Protected_Type then
803 Enclosing_Prot_Type := Current_Scope;
805 elsif Ekind (Current_Scope) = E_Function
806 and then Ekind (Scope (Current_Scope)) = E_Protected_Type
808 Enclosing_Prot_Type := Scope (Current_Scope);
811 if Present (Enclosing_Prot_Type) then
812 Anon_Scope := Scope (Enclosing_Prot_Type);
815 Anon_Scope := Scope (Defining_Entity (Related_Nod));
818 -- For an access type definition, if the current scope is a child
819 -- unit it is the scope of the type.
821 elsif Is_Compilation_Unit (Current_Scope) then
822 Anon_Scope := Current_Scope;
824 -- For access formals, access components, and access discriminants, the
825 -- scope is that of the enclosing declaration,
828 Anon_Scope := Scope (Current_Scope);
833 (E_Anonymous_Access_Type, Related_Nod, Scope_Id => Anon_Scope);
836 and then Ada_Version >= Ada_2005
838 Error_Msg_N ("ALL is not permitted for anonymous access types", N);
841 -- Ada 2005 (AI-254): In case of anonymous access to subprograms call
842 -- the corresponding semantic routine
844 if Present (Access_To_Subprogram_Definition (N)) then
846 -- Compiler runtime units are compiled in Ada 2005 mode when building
847 -- the runtime library but must also be compilable in Ada 95 mode
848 -- (when bootstrapping the compiler).
850 Check_Compiler_Unit ("anonymous access to subprogram", N);
852 Access_Subprogram_Declaration
853 (T_Name => Anon_Type,
854 T_Def => Access_To_Subprogram_Definition (N));
856 if Ekind (Anon_Type) = E_Access_Protected_Subprogram_Type then
858 (Anon_Type, E_Anonymous_Access_Protected_Subprogram_Type);
860 Set_Ekind (Anon_Type, E_Anonymous_Access_Subprogram_Type);
863 Set_Can_Use_Internal_Rep
864 (Anon_Type, not Always_Compatible_Rep_On_Target);
866 -- If the anonymous access is associated with a protected operation,
867 -- create a reference to it after the enclosing protected definition
868 -- because the itype will be used in the subsequent bodies.
870 -- If the anonymous access itself is protected, a full type
871 -- declaratiton will be created for it, so that the equivalent
872 -- record type can be constructed. For further details, see
873 -- Replace_Anonymous_Access_To_Protected-Subprogram.
875 if Ekind (Current_Scope) = E_Protected_Type
876 and then not Protected_Present (Access_To_Subprogram_Definition (N))
878 Build_Itype_Reference (Anon_Type, Parent (Current_Scope));
884 Find_Type (Subtype_Mark (N));
885 Desig_Type := Entity (Subtype_Mark (N));
887 Set_Directly_Designated_Type (Anon_Type, Desig_Type);
888 Set_Etype (Anon_Type, Anon_Type);
890 -- Make sure the anonymous access type has size and alignment fields
891 -- set, as required by gigi. This is necessary in the case of the
892 -- Task_Body_Procedure.
894 if not Has_Private_Component (Desig_Type) then
895 Layout_Type (Anon_Type);
898 -- Ada 2005 (AI-231): Ada 2005 semantics for anonymous access differs
899 -- from Ada 95 semantics. In Ada 2005, anonymous access must specify if
900 -- the null value is allowed. In Ada 95 the null value is never allowed.
902 if Ada_Version >= Ada_2005 then
903 Set_Can_Never_Be_Null (Anon_Type, Null_Exclusion_Present (N));
905 Set_Can_Never_Be_Null (Anon_Type, True);
908 -- The anonymous access type is as public as the discriminated type or
909 -- subprogram that defines it. It is imported (for back-end purposes)
910 -- if the designated type is.
912 Set_Is_Public (Anon_Type, Is_Public (Scope (Anon_Type)));
914 -- Ada 2005 (AI-231): Propagate the access-constant attribute
916 Set_Is_Access_Constant (Anon_Type, Constant_Present (N));
918 -- The context is either a subprogram declaration, object declaration,
919 -- or an access discriminant, in a private or a full type declaration.
920 -- In the case of a subprogram, if the designated type is incomplete,
921 -- the operation will be a primitive operation of the full type, to be
922 -- updated subsequently. If the type is imported through a limited_with
923 -- clause, the subprogram is not a primitive operation of the type
924 -- (which is declared elsewhere in some other scope).
926 if Ekind (Desig_Type) = E_Incomplete_Type
927 and then not From_Limited_With (Desig_Type)
928 and then Is_Overloadable (Current_Scope)
930 Append_Elmt (Current_Scope, Private_Dependents (Desig_Type));
931 Set_Has_Delayed_Freeze (Current_Scope);
934 -- Ada 2005: If the designated type is an interface that may contain
935 -- tasks, create a Master entity for the declaration. This must be done
936 -- before expansion of the full declaration, because the declaration may
937 -- include an expression that is an allocator, whose expansion needs the
938 -- proper Master for the created tasks.
940 if Nkind (Related_Nod) = N_Object_Declaration and then Expander_Active
942 if Is_Interface (Desig_Type) and then Is_Limited_Record (Desig_Type)
944 Build_Class_Wide_Master (Anon_Type);
946 -- Similarly, if the type is an anonymous access that designates
947 -- tasks, create a master entity for it in the current context.
949 elsif Has_Task (Desig_Type) and then Comes_From_Source (Related_Nod)
951 Build_Master_Entity (Defining_Identifier (Related_Nod));
952 Build_Master_Renaming (Anon_Type);
956 -- For a private component of a protected type, it is imperative that
957 -- the back-end elaborate the type immediately after the protected
958 -- declaration, because this type will be used in the declarations
959 -- created for the component within each protected body, so we must
960 -- create an itype reference for it now.
962 if Nkind (Parent (Related_Nod)) = N_Protected_Definition then
963 Build_Itype_Reference (Anon_Type, Parent (Parent (Related_Nod)));
965 -- Similarly, if the access definition is the return result of a
966 -- function, create an itype reference for it because it will be used
967 -- within the function body. For a regular function that is not a
968 -- compilation unit, insert reference after the declaration. For a
969 -- protected operation, insert it after the enclosing protected type
970 -- declaration. In either case, do not create a reference for a type
971 -- obtained through a limited_with clause, because this would introduce
972 -- semantic dependencies.
974 -- Similarly, do not create a reference if the designated type is a
975 -- generic formal, because no use of it will reach the backend.
977 elsif Nkind (Related_Nod) = N_Function_Specification
978 and then not From_Limited_With (Desig_Type)
979 and then not Is_Generic_Type (Desig_Type)
981 if Present (Enclosing_Prot_Type) then
982 Build_Itype_Reference (Anon_Type, Parent (Enclosing_Prot_Type));
984 elsif Is_List_Member (Parent (Related_Nod))
985 and then Nkind (Parent (N)) /= N_Parameter_Specification
987 Build_Itype_Reference (Anon_Type, Parent (Related_Nod));
990 -- Finally, create an itype reference for an object declaration of an
991 -- anonymous access type. This is strictly necessary only for deferred
992 -- constants, but in any case will avoid out-of-scope problems in the
995 elsif Nkind (Related_Nod) = N_Object_Declaration then
996 Build_Itype_Reference (Anon_Type, Related_Nod);
1000 end Access_Definition;
1002 -----------------------------------
1003 -- Access_Subprogram_Declaration --
1004 -----------------------------------
1006 procedure Access_Subprogram_Declaration
1007 (T_Name : Entity_Id;
1010 procedure Check_For_Premature_Usage (Def : Node_Id);
1011 -- Check that type T_Name is not used, directly or recursively, as a
1012 -- parameter or a return type in Def. Def is either a subtype, an
1013 -- access_definition, or an access_to_subprogram_definition.
1015 -------------------------------
1016 -- Check_For_Premature_Usage --
1017 -------------------------------
1019 procedure Check_For_Premature_Usage (Def : Node_Id) is
1023 -- Check for a subtype mark
1025 if Nkind (Def) in N_Has_Etype then
1026 if Etype (Def) = T_Name then
1028 ("type& cannot be used before end of its declaration", Def);
1031 -- If this is not a subtype, then this is an access_definition
1033 elsif Nkind (Def) = N_Access_Definition then
1034 if Present (Access_To_Subprogram_Definition (Def)) then
1035 Check_For_Premature_Usage
1036 (Access_To_Subprogram_Definition (Def));
1038 Check_For_Premature_Usage (Subtype_Mark (Def));
1041 -- The only cases left are N_Access_Function_Definition and
1042 -- N_Access_Procedure_Definition.
1045 if Present (Parameter_Specifications (Def)) then
1046 Param := First (Parameter_Specifications (Def));
1047 while Present (Param) loop
1048 Check_For_Premature_Usage (Parameter_Type (Param));
1049 Param := Next (Param);
1053 if Nkind (Def) = N_Access_Function_Definition then
1054 Check_For_Premature_Usage (Result_Definition (Def));
1057 end Check_For_Premature_Usage;
1061 Formals : constant List_Id := Parameter_Specifications (T_Def);
1064 Desig_Type : constant Entity_Id :=
1065 Create_Itype (E_Subprogram_Type, Parent (T_Def));
1067 -- Start of processing for Access_Subprogram_Declaration
1070 Check_SPARK_05_Restriction ("access type is not allowed", T_Def);
1072 -- Associate the Itype node with the inner full-type declaration or
1073 -- subprogram spec or entry body. This is required to handle nested
1074 -- anonymous declarations. For example:
1077 -- (X : access procedure
1078 -- (Y : access procedure
1081 D_Ityp := Associated_Node_For_Itype (Desig_Type);
1082 while not (Nkind_In (D_Ityp, N_Full_Type_Declaration,
1083 N_Private_Type_Declaration,
1084 N_Private_Extension_Declaration,
1085 N_Procedure_Specification,
1086 N_Function_Specification,
1090 Nkind_In (D_Ityp, N_Object_Declaration,
1091 N_Object_Renaming_Declaration,
1092 N_Formal_Object_Declaration,
1093 N_Formal_Type_Declaration,
1094 N_Task_Type_Declaration,
1095 N_Protected_Type_Declaration))
1097 D_Ityp := Parent (D_Ityp);
1098 pragma Assert (D_Ityp /= Empty);
1101 Set_Associated_Node_For_Itype (Desig_Type, D_Ityp);
1103 if Nkind_In (D_Ityp, N_Procedure_Specification,
1104 N_Function_Specification)
1106 Set_Scope (Desig_Type, Scope (Defining_Entity (D_Ityp)));
1108 elsif Nkind_In (D_Ityp, N_Full_Type_Declaration,
1109 N_Object_Declaration,
1110 N_Object_Renaming_Declaration,
1111 N_Formal_Type_Declaration)
1113 Set_Scope (Desig_Type, Scope (Defining_Identifier (D_Ityp)));
1116 if Nkind (T_Def) = N_Access_Function_Definition then
1117 if Nkind (Result_Definition (T_Def)) = N_Access_Definition then
1119 Acc : constant Node_Id := Result_Definition (T_Def);
1122 if Present (Access_To_Subprogram_Definition (Acc))
1124 Protected_Present (Access_To_Subprogram_Definition (Acc))
1128 Replace_Anonymous_Access_To_Protected_Subprogram
1134 Access_Definition (T_Def, Result_Definition (T_Def)));
1139 Analyze (Result_Definition (T_Def));
1142 Typ : constant Entity_Id := Entity (Result_Definition (T_Def));
1145 -- If a null exclusion is imposed on the result type, then
1146 -- create a null-excluding itype (an access subtype) and use
1147 -- it as the function's Etype.
1149 if Is_Access_Type (Typ)
1150 and then Null_Exclusion_In_Return_Present (T_Def)
1152 Set_Etype (Desig_Type,
1153 Create_Null_Excluding_Itype
1155 Related_Nod => T_Def,
1156 Scope_Id => Current_Scope));
1159 if From_Limited_With (Typ) then
1161 -- AI05-151: Incomplete types are allowed in all basic
1162 -- declarations, including access to subprograms.
1164 if Ada_Version >= Ada_2012 then
1169 ("illegal use of incomplete type&",
1170 Result_Definition (T_Def), Typ);
1173 elsif Ekind (Current_Scope) = E_Package
1174 and then In_Private_Part (Current_Scope)
1176 if Ekind (Typ) = E_Incomplete_Type then
1177 Append_Elmt (Desig_Type, Private_Dependents (Typ));
1179 elsif Is_Class_Wide_Type (Typ)
1180 and then Ekind (Etype (Typ)) = E_Incomplete_Type
1183 (Desig_Type, Private_Dependents (Etype (Typ)));
1187 Set_Etype (Desig_Type, Typ);
1192 if not (Is_Type (Etype (Desig_Type))) then
1194 ("expect type in function specification",
1195 Result_Definition (T_Def));
1199 Set_Etype (Desig_Type, Standard_Void_Type);
1202 if Present (Formals) then
1203 Push_Scope (Desig_Type);
1205 -- Some special tests here. These special tests can be removed
1206 -- if and when Itypes always have proper parent pointers to their
1209 -- Special test 1) Link defining_identifier of formals. Required by
1210 -- First_Formal to provide its functionality.
1216 F := First (Formals);
1218 -- In ASIS mode, the access_to_subprogram may be analyzed twice,
1219 -- when it is part of an unconstrained type and subtype expansion
1220 -- is disabled. To avoid back-end problems with shared profiles,
1221 -- use previous subprogram type as the designated type, and then
1222 -- remove scope added above.
1224 if ASIS_Mode and then Present (Scope (Defining_Identifier (F)))
1226 Set_Etype (T_Name, T_Name);
1227 Init_Size_Align (T_Name);
1228 Set_Directly_Designated_Type (T_Name,
1229 Scope (Defining_Identifier (F)));
1234 while Present (F) loop
1235 if No (Parent (Defining_Identifier (F))) then
1236 Set_Parent (Defining_Identifier (F), F);
1243 Process_Formals (Formals, Parent (T_Def));
1245 -- Special test 2) End_Scope requires that the parent pointer be set
1246 -- to something reasonable, but Itypes don't have parent pointers. So
1247 -- we set it and then unset it ???
1249 Set_Parent (Desig_Type, T_Name);
1251 Set_Parent (Desig_Type, Empty);
1254 -- Check for premature usage of the type being defined
1256 Check_For_Premature_Usage (T_Def);
1258 -- The return type and/or any parameter type may be incomplete. Mark the
1259 -- subprogram_type as depending on the incomplete type, so that it can
1260 -- be updated when the full type declaration is seen. This only applies
1261 -- to incomplete types declared in some enclosing scope, not to limited
1262 -- views from other packages.
1264 -- Prior to Ada 2012, access to functions can only have in_parameters.
1266 if Present (Formals) then
1267 Formal := First_Formal (Desig_Type);
1268 while Present (Formal) loop
1269 if Ekind (Formal) /= E_In_Parameter
1270 and then Nkind (T_Def) = N_Access_Function_Definition
1271 and then Ada_Version < Ada_2012
1273 Error_Msg_N ("functions can only have IN parameters", Formal);
1276 if Ekind (Etype (Formal)) = E_Incomplete_Type
1277 and then In_Open_Scopes (Scope (Etype (Formal)))
1279 Append_Elmt (Desig_Type, Private_Dependents (Etype (Formal)));
1280 Set_Has_Delayed_Freeze (Desig_Type);
1283 Next_Formal (Formal);
1287 -- Check whether an indirect call without actuals may be possible. This
1288 -- is used when resolving calls whose result is then indexed.
1290 May_Need_Actuals (Desig_Type);
1292 -- If the return type is incomplete, this is legal as long as the type
1293 -- is declared in the current scope and will be completed in it (rather
1294 -- than being part of limited view).
1296 if Ekind (Etype (Desig_Type)) = E_Incomplete_Type
1297 and then not Has_Delayed_Freeze (Desig_Type)
1298 and then In_Open_Scopes (Scope (Etype (Desig_Type)))
1300 Append_Elmt (Desig_Type, Private_Dependents (Etype (Desig_Type)));
1301 Set_Has_Delayed_Freeze (Desig_Type);
1304 Check_Delayed_Subprogram (Desig_Type);
1306 if Protected_Present (T_Def) then
1307 Set_Ekind (T_Name, E_Access_Protected_Subprogram_Type);
1308 Set_Convention (Desig_Type, Convention_Protected);
1310 Set_Ekind (T_Name, E_Access_Subprogram_Type);
1313 Set_Can_Use_Internal_Rep (T_Name, not Always_Compatible_Rep_On_Target);
1315 Set_Etype (T_Name, T_Name);
1316 Init_Size_Align (T_Name);
1317 Set_Directly_Designated_Type (T_Name, Desig_Type);
1319 Generate_Reference_To_Formals (T_Name);
1321 -- Ada 2005 (AI-231): Propagate the null-excluding attribute
1323 Set_Can_Never_Be_Null (T_Name, Null_Exclusion_Present (T_Def));
1325 Check_Restriction (No_Access_Subprograms, T_Def);
1326 end Access_Subprogram_Declaration;
1328 ----------------------------
1329 -- Access_Type_Declaration --
1330 ----------------------------
1332 procedure Access_Type_Declaration (T : Entity_Id; Def : Node_Id) is
1333 P : constant Node_Id := Parent (Def);
1334 S : constant Node_Id := Subtype_Indication (Def);
1336 Full_Desig : Entity_Id;
1339 Check_SPARK_05_Restriction ("access type is not allowed", Def);
1341 -- Check for permissible use of incomplete type
1343 if Nkind (S) /= N_Subtype_Indication then
1346 if Ekind (Root_Type (Entity (S))) = E_Incomplete_Type then
1347 Set_Directly_Designated_Type (T, Entity (S));
1349 -- If the designated type is a limited view, we cannot tell if
1350 -- the full view contains tasks, and there is no way to handle
1351 -- that full view in a client. We create a master entity for the
1352 -- scope, which will be used when a client determines that one
1355 if From_Limited_With (Entity (S))
1356 and then not Is_Class_Wide_Type (Entity (S))
1358 Set_Ekind (T, E_Access_Type);
1359 Build_Master_Entity (T);
1360 Build_Master_Renaming (T);
1364 Set_Directly_Designated_Type (T, Process_Subtype (S, P, T, 'P'));
1367 -- If the access definition is of the form: ACCESS NOT NULL ..
1368 -- the subtype indication must be of an access type. Create
1369 -- a null-excluding subtype of it.
1371 if Null_Excluding_Subtype (Def) then
1372 if not Is_Access_Type (Entity (S)) then
1373 Error_Msg_N ("null exclusion must apply to access type", Def);
1377 Loc : constant Source_Ptr := Sloc (S);
1379 Nam : constant Entity_Id := Make_Temporary (Loc, 'S');
1383 Make_Subtype_Declaration (Loc,
1384 Defining_Identifier => Nam,
1385 Subtype_Indication =>
1386 New_Occurrence_Of (Entity (S), Loc));
1387 Set_Null_Exclusion_Present (Decl);
1388 Insert_Before (Parent (Def), Decl);
1390 Set_Entity (S, Nam);
1396 Set_Directly_Designated_Type (T,
1397 Process_Subtype (S, P, T, 'P'));
1400 if All_Present (Def) or Constant_Present (Def) then
1401 Set_Ekind (T, E_General_Access_Type);
1403 Set_Ekind (T, E_Access_Type);
1406 Full_Desig := Designated_Type (T);
1408 if Base_Type (Full_Desig) = T then
1409 Error_Msg_N ("access type cannot designate itself", S);
1411 -- In Ada 2005, the type may have a limited view through some unit in
1412 -- its own context, allowing the following circularity that cannot be
1413 -- detected earlier.
1415 elsif Is_Class_Wide_Type (Full_Desig) and then Etype (Full_Desig) = T
1418 ("access type cannot designate its own classwide type", S);
1420 -- Clean up indication of tagged status to prevent cascaded errors
1422 Set_Is_Tagged_Type (T, False);
1427 -- If the type has appeared already in a with_type clause, it is frozen
1428 -- and the pointer size is already set. Else, initialize.
1430 if not From_Limited_With (T) then
1431 Init_Size_Align (T);
1434 -- Note that Has_Task is always false, since the access type itself
1435 -- is not a task type. See Einfo for more description on this point.
1436 -- Exactly the same consideration applies to Has_Controlled_Component
1437 -- and to Has_Protected.
1439 Set_Has_Task (T, False);
1440 Set_Has_Controlled_Component (T, False);
1441 Set_Has_Protected (T, False);
1443 -- Initialize field Finalization_Master explicitly to Empty, to avoid
1444 -- problems where an incomplete view of this entity has been previously
1445 -- established by a limited with and an overlaid version of this field
1446 -- (Stored_Constraint) was initialized for the incomplete view.
1448 -- This reset is performed in most cases except where the access type
1449 -- has been created for the purposes of allocating or deallocating a
1450 -- build-in-place object. Such access types have explicitly set pools
1451 -- and finalization masters.
1453 if No (Associated_Storage_Pool (T)) then
1454 Set_Finalization_Master (T, Empty);
1457 -- Ada 2005 (AI-231): Propagate the null-excluding and access-constant
1460 Set_Can_Never_Be_Null (T, Null_Exclusion_Present (Def));
1461 Set_Is_Access_Constant (T, Constant_Present (Def));
1462 end Access_Type_Declaration;
1464 ----------------------------------
1465 -- Add_Interface_Tag_Components --
1466 ----------------------------------
1468 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id) is
1469 Loc : constant Source_Ptr := Sloc (N);
1473 procedure Add_Tag (Iface : Entity_Id);
1474 -- Add tag for one of the progenitor interfaces
1480 procedure Add_Tag (Iface : Entity_Id) is
1487 pragma Assert (Is_Tagged_Type (Iface) and then Is_Interface (Iface));
1489 -- This is a reasonable place to propagate predicates
1491 if Has_Predicates (Iface) then
1492 Set_Has_Predicates (Typ);
1496 Make_Component_Definition (Loc,
1497 Aliased_Present => True,
1498 Subtype_Indication =>
1499 New_Occurrence_Of (RTE (RE_Interface_Tag), Loc));
1501 Tag := Make_Temporary (Loc, 'V');
1504 Make_Component_Declaration (Loc,
1505 Defining_Identifier => Tag,
1506 Component_Definition => Def);
1508 Analyze_Component_Declaration (Decl);
1510 Set_Analyzed (Decl);
1511 Set_Ekind (Tag, E_Component);
1513 Set_Is_Aliased (Tag);
1514 Set_Related_Type (Tag, Iface);
1515 Init_Component_Location (Tag);
1517 pragma Assert (Is_Frozen (Iface));
1519 Set_DT_Entry_Count (Tag,
1520 DT_Entry_Count (First_Entity (Iface)));
1522 if No (Last_Tag) then
1525 Insert_After (Last_Tag, Decl);
1530 -- If the ancestor has discriminants we need to give special support
1531 -- to store the offset_to_top value of the secondary dispatch tables.
1532 -- For this purpose we add a supplementary component just after the
1533 -- field that contains the tag associated with each secondary DT.
1535 if Typ /= Etype (Typ) and then Has_Discriminants (Etype (Typ)) then
1537 Make_Component_Definition (Loc,
1538 Subtype_Indication =>
1539 New_Occurrence_Of (RTE (RE_Storage_Offset), Loc));
1541 Offset := Make_Temporary (Loc, 'V');
1544 Make_Component_Declaration (Loc,
1545 Defining_Identifier => Offset,
1546 Component_Definition => Def);
1548 Analyze_Component_Declaration (Decl);
1550 Set_Analyzed (Decl);
1551 Set_Ekind (Offset, E_Component);
1552 Set_Is_Aliased (Offset);
1553 Set_Related_Type (Offset, Iface);
1554 Init_Component_Location (Offset);
1555 Insert_After (Last_Tag, Decl);
1566 -- Start of processing for Add_Interface_Tag_Components
1569 if not RTE_Available (RE_Interface_Tag) then
1571 ("(Ada 2005) interface types not supported by this run-time!",
1576 if Ekind (Typ) /= E_Record_Type
1577 or else (Is_Concurrent_Record_Type (Typ)
1578 and then Is_Empty_List (Abstract_Interface_List (Typ)))
1579 or else (not Is_Concurrent_Record_Type (Typ)
1580 and then No (Interfaces (Typ))
1581 and then Is_Empty_Elmt_List (Interfaces (Typ)))
1586 -- Find the current last tag
1588 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1589 Ext := Record_Extension_Part (Type_Definition (N));
1591 pragma Assert (Nkind (Type_Definition (N)) = N_Record_Definition);
1592 Ext := Type_Definition (N);
1597 if not (Present (Component_List (Ext))) then
1598 Set_Null_Present (Ext, False);
1600 Set_Component_List (Ext,
1601 Make_Component_List (Loc,
1602 Component_Items => L,
1603 Null_Present => False));
1605 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1606 L := Component_Items
1608 (Record_Extension_Part
1609 (Type_Definition (N))));
1611 L := Component_Items
1613 (Type_Definition (N)));
1616 -- Find the last tag component
1619 while Present (Comp) loop
1620 if Nkind (Comp) = N_Component_Declaration
1621 and then Is_Tag (Defining_Identifier (Comp))
1630 -- At this point L references the list of components and Last_Tag
1631 -- references the current last tag (if any). Now we add the tag
1632 -- corresponding with all the interfaces that are not implemented
1635 if Present (Interfaces (Typ)) then
1636 Elmt := First_Elmt (Interfaces (Typ));
1637 while Present (Elmt) loop
1638 Add_Tag (Node (Elmt));
1642 end Add_Interface_Tag_Components;
1644 -------------------------------------
1645 -- Add_Internal_Interface_Entities --
1646 -------------------------------------
1648 procedure Add_Internal_Interface_Entities (Tagged_Type : Entity_Id) is
1651 Iface_Elmt : Elmt_Id;
1652 Iface_Prim : Entity_Id;
1653 Ifaces_List : Elist_Id;
1654 New_Subp : Entity_Id := Empty;
1656 Restore_Scope : Boolean := False;
1659 pragma Assert (Ada_Version >= Ada_2005
1660 and then Is_Record_Type (Tagged_Type)
1661 and then Is_Tagged_Type (Tagged_Type)
1662 and then Has_Interfaces (Tagged_Type)
1663 and then not Is_Interface (Tagged_Type));
1665 -- Ensure that the internal entities are added to the scope of the type
1667 if Scope (Tagged_Type) /= Current_Scope then
1668 Push_Scope (Scope (Tagged_Type));
1669 Restore_Scope := True;
1672 Collect_Interfaces (Tagged_Type, Ifaces_List);
1674 Iface_Elmt := First_Elmt (Ifaces_List);
1675 while Present (Iface_Elmt) loop
1676 Iface := Node (Iface_Elmt);
1678 -- Originally we excluded here from this processing interfaces that
1679 -- are parents of Tagged_Type because their primitives are located
1680 -- in the primary dispatch table (and hence no auxiliary internal
1681 -- entities are required to handle secondary dispatch tables in such
1682 -- case). However, these auxiliary entities are also required to
1683 -- handle derivations of interfaces in formals of generics (see
1684 -- Derive_Subprograms).
1686 Elmt := First_Elmt (Primitive_Operations (Iface));
1687 while Present (Elmt) loop
1688 Iface_Prim := Node (Elmt);
1690 if not Is_Predefined_Dispatching_Operation (Iface_Prim) then
1692 Find_Primitive_Covering_Interface
1693 (Tagged_Type => Tagged_Type,
1694 Iface_Prim => Iface_Prim);
1696 if No (Prim) and then Serious_Errors_Detected > 0 then
1700 pragma Assert (Present (Prim));
1702 -- Ada 2012 (AI05-0197): If the name of the covering primitive
1703 -- differs from the name of the interface primitive then it is
1704 -- a private primitive inherited from a parent type. In such
1705 -- case, given that Tagged_Type covers the interface, the
1706 -- inherited private primitive becomes visible. For such
1707 -- purpose we add a new entity that renames the inherited
1708 -- private primitive.
1710 if Chars (Prim) /= Chars (Iface_Prim) then
1711 pragma Assert (Has_Suffix (Prim, 'P'));
1713 (New_Subp => New_Subp,
1714 Parent_Subp => Iface_Prim,
1715 Derived_Type => Tagged_Type,
1716 Parent_Type => Iface);
1717 Set_Alias (New_Subp, Prim);
1718 Set_Is_Abstract_Subprogram
1719 (New_Subp, Is_Abstract_Subprogram (Prim));
1723 (New_Subp => New_Subp,
1724 Parent_Subp => Iface_Prim,
1725 Derived_Type => Tagged_Type,
1726 Parent_Type => Iface);
1728 -- Ada 2005 (AI-251): Decorate internal entity Iface_Subp
1729 -- associated with interface types. These entities are
1730 -- only registered in the list of primitives of its
1731 -- corresponding tagged type because they are only used
1732 -- to fill the contents of the secondary dispatch tables.
1733 -- Therefore they are removed from the homonym chains.
1735 Set_Is_Hidden (New_Subp);
1736 Set_Is_Internal (New_Subp);
1737 Set_Alias (New_Subp, Prim);
1738 Set_Is_Abstract_Subprogram
1739 (New_Subp, Is_Abstract_Subprogram (Prim));
1740 Set_Interface_Alias (New_Subp, Iface_Prim);
1742 -- If the returned type is an interface then propagate it to
1743 -- the returned type. Needed by the thunk to generate the code
1744 -- which displaces "this" to reference the corresponding
1745 -- secondary dispatch table in the returned object.
1747 if Is_Interface (Etype (Iface_Prim)) then
1748 Set_Etype (New_Subp, Etype (Iface_Prim));
1751 -- Internal entities associated with interface types are only
1752 -- registered in the list of primitives of the tagged type.
1753 -- They are only used to fill the contents of the secondary
1754 -- dispatch tables. Therefore they are not needed in the
1757 Remove_Homonym (New_Subp);
1759 -- Hidden entities associated with interfaces must have set
1760 -- the Has_Delay_Freeze attribute to ensure that, in case
1761 -- of locally defined tagged types (or compiling with static
1762 -- dispatch tables generation disabled) the corresponding
1763 -- entry of the secondary dispatch table is filled when such
1764 -- an entity is frozen. This is an expansion activity that must
1765 -- be suppressed for ASIS because it leads to gigi elaboration
1766 -- issues in annotate mode.
1768 if not ASIS_Mode then
1769 Set_Has_Delayed_Freeze (New_Subp);
1777 Next_Elmt (Iface_Elmt);
1780 if Restore_Scope then
1783 end Add_Internal_Interface_Entities;
1785 -----------------------------------
1786 -- Analyze_Component_Declaration --
1787 -----------------------------------
1789 procedure Analyze_Component_Declaration (N : Node_Id) is
1790 Loc : constant Source_Ptr := Sloc (Component_Definition (N));
1791 Id : constant Entity_Id := Defining_Identifier (N);
1792 E : constant Node_Id := Expression (N);
1793 Typ : constant Node_Id :=
1794 Subtype_Indication (Component_Definition (N));
1798 function Contains_POC (Constr : Node_Id) return Boolean;
1799 -- Determines whether a constraint uses the discriminant of a record
1800 -- type thus becoming a per-object constraint (POC).
1802 function Is_Known_Limited (Typ : Entity_Id) return Boolean;
1803 -- Typ is the type of the current component, check whether this type is
1804 -- a limited type. Used to validate declaration against that of
1805 -- enclosing record.
1811 function Contains_POC (Constr : Node_Id) return Boolean is
1813 -- Prevent cascaded errors
1815 if Error_Posted (Constr) then
1819 case Nkind (Constr) is
1820 when N_Attribute_Reference =>
1821 return Attribute_Name (Constr) = Name_Access
1822 and then Prefix (Constr) = Scope (Entity (Prefix (Constr)));
1824 when N_Discriminant_Association =>
1825 return Denotes_Discriminant (Expression (Constr));
1827 when N_Identifier =>
1828 return Denotes_Discriminant (Constr);
1830 when N_Index_Or_Discriminant_Constraint =>
1835 IDC := First (Constraints (Constr));
1836 while Present (IDC) loop
1838 -- One per-object constraint is sufficient
1840 if Contains_POC (IDC) then
1851 return Denotes_Discriminant (Low_Bound (Constr))
1853 Denotes_Discriminant (High_Bound (Constr));
1855 when N_Range_Constraint =>
1856 return Denotes_Discriminant (Range_Expression (Constr));
1864 ----------------------
1865 -- Is_Known_Limited --
1866 ----------------------
1868 function Is_Known_Limited (Typ : Entity_Id) return Boolean is
1869 P : constant Entity_Id := Etype (Typ);
1870 R : constant Entity_Id := Root_Type (Typ);
1873 if Is_Limited_Record (Typ) then
1876 -- If the root type is limited (and not a limited interface)
1877 -- so is the current type
1879 elsif Is_Limited_Record (R)
1880 and then (not Is_Interface (R) or else not Is_Limited_Interface (R))
1884 -- Else the type may have a limited interface progenitor, but a
1885 -- limited record parent.
1887 elsif R /= P and then Is_Limited_Record (P) then
1893 end Is_Known_Limited;
1895 -- Start of processing for Analyze_Component_Declaration
1898 Generate_Definition (Id);
1901 if Present (Typ) then
1902 T := Find_Type_Of_Object
1903 (Subtype_Indication (Component_Definition (N)), N);
1905 if not Nkind_In (Typ, N_Identifier, N_Expanded_Name) then
1906 Check_SPARK_05_Restriction ("subtype mark required", Typ);
1909 -- Ada 2005 (AI-230): Access Definition case
1912 pragma Assert (Present
1913 (Access_Definition (Component_Definition (N))));
1915 T := Access_Definition
1917 N => Access_Definition (Component_Definition (N)));
1918 Set_Is_Local_Anonymous_Access (T);
1920 -- Ada 2005 (AI-254)
1922 if Present (Access_To_Subprogram_Definition
1923 (Access_Definition (Component_Definition (N))))
1924 and then Protected_Present (Access_To_Subprogram_Definition
1926 (Component_Definition (N))))
1928 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1932 -- If the subtype is a constrained subtype of the enclosing record,
1933 -- (which must have a partial view) the back-end does not properly
1934 -- handle the recursion. Rewrite the component declaration with an
1935 -- explicit subtype indication, which is acceptable to Gigi. We can copy
1936 -- the tree directly because side effects have already been removed from
1937 -- discriminant constraints.
1939 if Ekind (T) = E_Access_Subtype
1940 and then Is_Entity_Name (Subtype_Indication (Component_Definition (N)))
1941 and then Comes_From_Source (T)
1942 and then Nkind (Parent (T)) = N_Subtype_Declaration
1943 and then Etype (Directly_Designated_Type (T)) = Current_Scope
1946 (Subtype_Indication (Component_Definition (N)),
1947 New_Copy_Tree (Subtype_Indication (Parent (T))));
1948 T := Find_Type_Of_Object
1949 (Subtype_Indication (Component_Definition (N)), N);
1952 -- If the component declaration includes a default expression, then we
1953 -- check that the component is not of a limited type (RM 3.7(5)),
1954 -- and do the special preanalysis of the expression (see section on
1955 -- "Handling of Default and Per-Object Expressions" in the spec of
1959 Check_SPARK_05_Restriction ("default expression is not allowed", E);
1960 Preanalyze_Default_Expression (E, T);
1961 Check_Initialization (T, E);
1963 if Ada_Version >= Ada_2005
1964 and then Ekind (T) = E_Anonymous_Access_Type
1965 and then Etype (E) /= Any_Type
1967 -- Check RM 3.9.2(9): "if the expected type for an expression is
1968 -- an anonymous access-to-specific tagged type, then the object
1969 -- designated by the expression shall not be dynamically tagged
1970 -- unless it is a controlling operand in a call on a dispatching
1973 if Is_Tagged_Type (Directly_Designated_Type (T))
1975 Ekind (Directly_Designated_Type (T)) /= E_Class_Wide_Type
1977 Ekind (Directly_Designated_Type (Etype (E))) =
1981 ("access to specific tagged type required (RM 3.9.2(9))", E);
1984 -- (Ada 2005: AI-230): Accessibility check for anonymous
1987 if Type_Access_Level (Etype (E)) >
1988 Deepest_Type_Access_Level (T)
1991 ("expression has deeper access level than component " &
1992 "(RM 3.10.2 (12.2))", E);
1995 -- The initialization expression is a reference to an access
1996 -- discriminant. The type of the discriminant is always deeper
1997 -- than any access type.
1999 if Ekind (Etype (E)) = E_Anonymous_Access_Type
2000 and then Is_Entity_Name (E)
2001 and then Ekind (Entity (E)) = E_In_Parameter
2002 and then Present (Discriminal_Link (Entity (E)))
2005 ("discriminant has deeper accessibility level than target",
2011 -- The parent type may be a private view with unknown discriminants,
2012 -- and thus unconstrained. Regular components must be constrained.
2014 if not Is_Definite_Subtype (T) and then Chars (Id) /= Name_uParent then
2015 if Is_Class_Wide_Type (T) then
2017 ("class-wide subtype with unknown discriminants" &
2018 " in component declaration",
2019 Subtype_Indication (Component_Definition (N)));
2022 ("unconstrained subtype in component declaration",
2023 Subtype_Indication (Component_Definition (N)));
2026 -- Components cannot be abstract, except for the special case of
2027 -- the _Parent field (case of extending an abstract tagged type)
2029 elsif Is_Abstract_Type (T) and then Chars (Id) /= Name_uParent then
2030 Error_Msg_N ("type of a component cannot be abstract", N);
2034 Set_Is_Aliased (Id, Aliased_Present (Component_Definition (N)));
2036 -- The component declaration may have a per-object constraint, set
2037 -- the appropriate flag in the defining identifier of the subtype.
2039 if Present (Subtype_Indication (Component_Definition (N))) then
2041 Sindic : constant Node_Id :=
2042 Subtype_Indication (Component_Definition (N));
2044 if Nkind (Sindic) = N_Subtype_Indication
2045 and then Present (Constraint (Sindic))
2046 and then Contains_POC (Constraint (Sindic))
2048 Set_Has_Per_Object_Constraint (Id);
2053 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
2054 -- out some static checks.
2056 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
2057 Null_Exclusion_Static_Checks (N);
2060 -- If this component is private (or depends on a private type), flag the
2061 -- record type to indicate that some operations are not available.
2063 P := Private_Component (T);
2067 -- Check for circular definitions
2069 if P = Any_Type then
2070 Set_Etype (Id, Any_Type);
2072 -- There is a gap in the visibility of operations only if the
2073 -- component type is not defined in the scope of the record type.
2075 elsif Scope (P) = Scope (Current_Scope) then
2078 elsif Is_Limited_Type (P) then
2079 Set_Is_Limited_Composite (Current_Scope);
2082 Set_Is_Private_Composite (Current_Scope);
2087 and then Is_Limited_Type (T)
2088 and then Chars (Id) /= Name_uParent
2089 and then Is_Tagged_Type (Current_Scope)
2091 if Is_Derived_Type (Current_Scope)
2092 and then not Is_Known_Limited (Current_Scope)
2095 ("extension of nonlimited type cannot have limited components",
2098 if Is_Interface (Root_Type (Current_Scope)) then
2100 ("\limitedness is not inherited from limited interface", N);
2101 Error_Msg_N ("\add LIMITED to type indication", N);
2104 Explain_Limited_Type (T, N);
2105 Set_Etype (Id, Any_Type);
2106 Set_Is_Limited_Composite (Current_Scope, False);
2108 elsif not Is_Derived_Type (Current_Scope)
2109 and then not Is_Limited_Record (Current_Scope)
2110 and then not Is_Concurrent_Type (Current_Scope)
2113 ("nonlimited tagged type cannot have limited components", N);
2114 Explain_Limited_Type (T, N);
2115 Set_Etype (Id, Any_Type);
2116 Set_Is_Limited_Composite (Current_Scope, False);
2120 -- If the component is an unconstrained task or protected type with
2121 -- discriminants, the component and the enclosing record are limited
2122 -- and the component is constrained by its default values. Compute
2123 -- its actual subtype, else it may be allocated the maximum size by
2124 -- the backend, and possibly overflow.
2126 if Is_Concurrent_Type (T)
2127 and then not Is_Constrained (T)
2128 and then Has_Discriminants (T)
2129 and then not Has_Discriminants (Current_Scope)
2132 Act_T : constant Entity_Id := Build_Default_Subtype (T, N);
2135 Set_Etype (Id, Act_T);
2137 -- Rewrite component definition to use the constrained subtype
2139 Rewrite (Component_Definition (N),
2140 Make_Component_Definition (Loc,
2141 Subtype_Indication => New_Occurrence_Of (Act_T, Loc)));
2145 Set_Original_Record_Component (Id, Id);
2147 if Has_Aspects (N) then
2148 Analyze_Aspect_Specifications (N, Id);
2151 Analyze_Dimension (N);
2152 end Analyze_Component_Declaration;
2154 --------------------------
2155 -- Analyze_Declarations --
2156 --------------------------
2158 procedure Analyze_Declarations (L : List_Id) is
2161 procedure Adjust_Decl;
2162 -- Adjust Decl not to include implicit label declarations, since these
2163 -- have strange Sloc values that result in elaboration check problems.
2164 -- (They have the sloc of the label as found in the source, and that
2165 -- is ahead of the current declarative part).
2167 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id);
2168 -- Determine whether Body_Decl denotes the body of a late controlled
2169 -- primitive (either Initialize, Adjust or Finalize). If this is the
2170 -- case, add a proper spec if the body lacks one. The spec is inserted
2171 -- before Body_Decl and immedately analyzed.
2173 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id);
2174 -- Spec_Id is the entity of a package that may define abstract states.
2175 -- If the states have visible refinement, remove the visibility of each
2176 -- constituent at the end of the package body declarations.
2182 procedure Adjust_Decl is
2184 while Present (Prev (Decl))
2185 and then Nkind (Decl) = N_Implicit_Label_Declaration
2191 --------------------------------------
2192 -- Handle_Late_Controlled_Primitive --
2193 --------------------------------------
2195 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id) is
2196 Body_Spec : constant Node_Id := Specification (Body_Decl);
2197 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2198 Loc : constant Source_Ptr := Sloc (Body_Id);
2199 Params : constant List_Id :=
2200 Parameter_Specifications (Body_Spec);
2202 Spec_Id : Entity_Id;
2206 -- Consider only procedure bodies whose name matches one of the three
2207 -- controlled primitives.
2209 if Nkind (Body_Spec) /= N_Procedure_Specification
2210 or else not Nam_In (Chars (Body_Id), Name_Adjust,
2216 -- A controlled primitive must have exactly one formal which is not
2217 -- an anonymous access type.
2219 elsif List_Length (Params) /= 1 then
2223 Typ := Parameter_Type (First (Params));
2225 if Nkind (Typ) = N_Access_Definition then
2231 -- The type of the formal must be derived from [Limited_]Controlled
2233 if not Is_Controlled (Entity (Typ)) then
2237 -- Check whether a specification exists for this body. We do not
2238 -- analyze the spec of the body in full, because it will be analyzed
2239 -- again when the body is properly analyzed, and we cannot create
2240 -- duplicate entries in the formals chain. We look for an explicit
2241 -- specification because the body may be an overriding operation and
2242 -- an inherited spec may be present.
2244 Spec_Id := Current_Entity (Body_Id);
2246 while Present (Spec_Id) loop
2247 if Ekind_In (Spec_Id, E_Procedure, E_Generic_Procedure)
2248 and then Scope (Spec_Id) = Current_Scope
2249 and then Present (First_Formal (Spec_Id))
2250 and then No (Next_Formal (First_Formal (Spec_Id)))
2251 and then Etype (First_Formal (Spec_Id)) = Entity (Typ)
2252 and then Comes_From_Source (Spec_Id)
2257 Spec_Id := Homonym (Spec_Id);
2260 -- At this point the body is known to be a late controlled primitive.
2261 -- Generate a matching spec and insert it before the body. Note the
2262 -- use of Copy_Separate_Tree - we want an entirely separate semantic
2263 -- tree in this case.
2265 Spec := Copy_Separate_Tree (Body_Spec);
2267 -- Ensure that the subprogram declaration does not inherit the null
2268 -- indicator from the body as we now have a proper spec/body pair.
2270 Set_Null_Present (Spec, False);
2272 Insert_Before_And_Analyze (Body_Decl,
2273 Make_Subprogram_Declaration (Loc, Specification => Spec));
2274 end Handle_Late_Controlled_Primitive;
2276 --------------------------------
2277 -- Remove_Visible_Refinements --
2278 --------------------------------
2280 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id) is
2281 State_Elmt : Elmt_Id;
2283 if Present (Abstract_States (Spec_Id)) then
2284 State_Elmt := First_Elmt (Abstract_States (Spec_Id));
2285 while Present (State_Elmt) loop
2286 Set_Has_Visible_Refinement (Node (State_Elmt), False);
2287 Next_Elmt (State_Elmt);
2290 end Remove_Visible_Refinements;
2294 Context : Node_Id := Empty;
2295 Freeze_From : Entity_Id := Empty;
2296 Next_Decl : Node_Id;
2298 Body_Seen : Boolean := False;
2299 -- Flag set when the first body [stub] is encountered
2301 -- Start of processing for Analyze_Declarations
2304 if Restriction_Check_Required (SPARK_05) then
2305 Check_Later_Vs_Basic_Declarations (L, During_Parsing => False);
2309 while Present (Decl) loop
2311 -- Package spec cannot contain a package declaration in SPARK
2313 if Nkind (Decl) = N_Package_Declaration
2314 and then Nkind (Parent (L)) = N_Package_Specification
2316 Check_SPARK_05_Restriction
2317 ("package specification cannot contain a package declaration",
2321 -- Complete analysis of declaration
2324 Next_Decl := Next (Decl);
2326 if No (Freeze_From) then
2327 Freeze_From := First_Entity (Current_Scope);
2330 -- At the end of a declarative part, freeze remaining entities
2331 -- declared in it. The end of the visible declarations of package
2332 -- specification is not the end of a declarative part if private
2333 -- declarations are present. The end of a package declaration is a
2334 -- freezing point only if it a library package. A task definition or
2335 -- protected type definition is not a freeze point either. Finally,
2336 -- we do not freeze entities in generic scopes, because there is no
2337 -- code generated for them and freeze nodes will be generated for
2340 -- The end of a package instantiation is not a freeze point, but
2341 -- for now we make it one, because the generic body is inserted
2342 -- (currently) immediately after. Generic instantiations will not
2343 -- be a freeze point once delayed freezing of bodies is implemented.
2344 -- (This is needed in any case for early instantiations ???).
2346 if No (Next_Decl) then
2347 if Nkind_In (Parent (L), N_Component_List,
2349 N_Protected_Definition)
2353 elsif Nkind (Parent (L)) /= N_Package_Specification then
2354 if Nkind (Parent (L)) = N_Package_Body then
2355 Freeze_From := First_Entity (Current_Scope);
2358 -- There may have been several freezing points previously,
2359 -- for example object declarations or subprogram bodies, but
2360 -- at the end of a declarative part we check freezing from
2361 -- the beginning, even though entities may already be frozen,
2362 -- in order to perform visibility checks on delayed aspects.
2365 Freeze_All (First_Entity (Current_Scope), Decl);
2366 Freeze_From := Last_Entity (Current_Scope);
2368 elsif Scope (Current_Scope) /= Standard_Standard
2369 and then not Is_Child_Unit (Current_Scope)
2370 and then No (Generic_Parent (Parent (L)))
2374 elsif L /= Visible_Declarations (Parent (L))
2375 or else No (Private_Declarations (Parent (L)))
2376 or else Is_Empty_List (Private_Declarations (Parent (L)))
2379 Freeze_All (First_Entity (Current_Scope), Decl);
2380 Freeze_From := Last_Entity (Current_Scope);
2382 -- At the end of the visible declarations the expressions in
2383 -- aspects of all entities declared so far must be resolved.
2384 -- The entities themselves might be frozen later, and the
2385 -- generated pragmas and attribute definition clauses analyzed
2386 -- in full at that point, but name resolution must take place
2388 -- In addition to being the proper semantics, this is mandatory
2389 -- within generic units, because global name capture requires
2390 -- those expressions to be analyzed, given that the generated
2391 -- pragmas do not appear in the original generic tree.
2393 elsif Serious_Errors_Detected = 0 then
2398 E := First_Entity (Current_Scope);
2399 while Present (E) loop
2400 Resolve_Aspect_Expressions (E);
2406 -- If next node is a body then freeze all types before the body.
2407 -- An exception occurs for some expander-generated bodies. If these
2408 -- are generated at places where in general language rules would not
2409 -- allow a freeze point, then we assume that the expander has
2410 -- explicitly checked that all required types are properly frozen,
2411 -- and we do not cause general freezing here. This special circuit
2412 -- is used when the encountered body is marked as having already
2415 -- In all other cases (bodies that come from source, and expander
2416 -- generated bodies that have not been analyzed yet), freeze all
2417 -- types now. Note that in the latter case, the expander must take
2418 -- care to attach the bodies at a proper place in the tree so as to
2419 -- not cause unwanted freezing at that point.
2421 elsif not Analyzed (Next_Decl) and then Is_Body (Next_Decl) then
2423 -- When a controlled type is frozen, the expander generates stream
2424 -- and controlled type support routines. If the freeze is caused
2425 -- by the stand alone body of Initialize, Adjust and Finalize, the
2426 -- expander will end up using the wrong version of these routines
2427 -- as the body has not been processed yet. To remedy this, detect
2428 -- a late controlled primitive and create a proper spec for it.
2429 -- This ensures that the primitive will override its inherited
2430 -- counterpart before the freeze takes place.
2432 -- If the declaration we just processed is a body, do not attempt
2433 -- to examine Next_Decl as the late primitive idiom can only apply
2434 -- to the first encountered body.
2436 -- The spec of the late primitive is not generated in ASIS mode to
2437 -- ensure a consistent list of primitives that indicates the true
2438 -- semantic structure of the program (which is not relevant when
2439 -- generating executable code.
2441 -- ??? a cleaner approach may be possible and/or this solution
2442 -- could be extended to general-purpose late primitives, TBD.
2444 if not ASIS_Mode and then not Body_Seen and then not Is_Body (Decl)
2448 if Nkind (Next_Decl) = N_Subprogram_Body then
2449 Handle_Late_Controlled_Primitive (Next_Decl);
2454 Freeze_All (Freeze_From, Decl);
2455 Freeze_From := Last_Entity (Current_Scope);
2461 -- Analyze the contracts of packages and their bodies
2464 Context := Parent (L);
2466 if Nkind (Context) = N_Package_Specification then
2468 -- When a package has private declarations, its contract must be
2469 -- analyzed at the end of the said declarations. This way both the
2470 -- analysis and freeze actions are properly synchronized in case
2471 -- of private type use within the contract.
2473 if L = Private_Declarations (Context) then
2474 Analyze_Package_Contract (Defining_Entity (Context));
2476 -- Build the bodies of the default initial condition procedures
2477 -- for all types subject to pragma Default_Initial_Condition.
2478 -- From a purely Ada stand point, this is a freezing activity,
2479 -- however freezing is not available under GNATprove_Mode. To
2480 -- accomodate both scenarios, the bodies are build at the end
2481 -- of private declaration analysis.
2483 Build_Default_Init_Cond_Procedure_Bodies (L);
2485 -- Otherwise the contract is analyzed at the end of the visible
2488 elsif L = Visible_Declarations (Context)
2489 and then No (Private_Declarations (Context))
2491 Analyze_Package_Contract (Defining_Entity (Context));
2494 elsif Nkind (Context) = N_Package_Body then
2495 Analyze_Package_Body_Contract (Defining_Entity (Context));
2498 -- Analyze the contracts of various constructs now due to the delayed
2499 -- visibility needs of their aspects and pragmas.
2501 Analyze_Contracts (L);
2503 if Nkind (Context) = N_Package_Body then
2505 -- Ensure that all abstract states and objects declared in the
2506 -- state space of a package body are utilized as constituents.
2508 Check_Unused_Body_States (Defining_Entity (Context));
2510 -- State refinements are visible up to the end of the package body
2511 -- declarations. Hide the state refinements from visibility to
2512 -- restore the original state conditions.
2514 Remove_Visible_Refinements (Corresponding_Spec (Context));
2517 end Analyze_Declarations;
2519 -----------------------------------
2520 -- Analyze_Full_Type_Declaration --
2521 -----------------------------------
2523 procedure Analyze_Full_Type_Declaration (N : Node_Id) is
2524 Def : constant Node_Id := Type_Definition (N);
2525 Def_Id : constant Entity_Id := Defining_Identifier (N);
2529 Is_Remote : constant Boolean :=
2530 (Is_Remote_Types (Current_Scope)
2531 or else Is_Remote_Call_Interface (Current_Scope))
2532 and then not (In_Private_Part (Current_Scope)
2533 or else In_Package_Body (Current_Scope));
2535 procedure Check_Nonoverridable_Aspects;
2536 -- Apply the rule in RM 13.1.1(18.4/4) on iterator aspects that cannot
2537 -- be overridden, and can only be confirmed on derivation.
2539 procedure Check_Ops_From_Incomplete_Type;
2540 -- If there is a tagged incomplete partial view of the type, traverse
2541 -- the primitives of the incomplete view and change the type of any
2542 -- controlling formals and result to indicate the full view. The
2543 -- primitives will be added to the full type's primitive operations
2544 -- list later in Sem_Disp.Check_Operation_From_Incomplete_Type (which
2545 -- is called from Process_Incomplete_Dependents).
2547 ----------------------------------
2548 -- Check_Nonoverridable_Aspects --
2549 ----------------------------------
2551 procedure Check_Nonoverridable_Aspects is
2552 Prev_Aspects : constant List_Id :=
2553 Aspect_Specifications (Parent (Def_Id));
2554 Par_Type : Entity_Id;
2556 function Has_Aspect_Spec
2558 Aspect_Name : Name_Id) return Boolean;
2559 -- Check whether a list of aspect specifications includes an entry
2560 -- for a specific aspect. The list is either that of a partial or
2563 ---------------------
2564 -- Has_Aspect_Spec --
2565 ---------------------
2567 function Has_Aspect_Spec
2569 Aspect_Name : Name_Id) return Boolean
2573 Spec := First (Specs);
2574 while Present (Spec) loop
2575 if Chars (Identifier (Spec)) = Aspect_Name then
2581 end Has_Aspect_Spec;
2583 -- Start of processing for Check_Nonoverridable_Aspects
2587 -- Get parent type of derived type. Note that Prev is the entity
2588 -- in the partial declaration, but its contents are now those of
2589 -- full view, while Def_Id reflects the partial view.
2591 if Is_Private_Type (Def_Id) then
2592 Par_Type := Etype (Full_View (Def_Id));
2594 Par_Type := Etype (Def_Id);
2597 -- If there is an inherited Implicit_Dereference, verify that it is
2598 -- made explicit in the partial view.
2600 if Has_Discriminants (Base_Type (Par_Type))
2601 and then Nkind (Parent (Prev)) = N_Full_Type_Declaration
2602 and then Present (Discriminant_Specifications (Parent (Prev)))
2603 and then Present (Get_Reference_Discriminant (Par_Type))
2606 not Has_Aspect_Spec (Prev_Aspects, Name_Implicit_Dereference)
2609 ("type does not inherit implicit dereference", Prev);
2612 -- If one of the views has the aspect specified, verify that it
2613 -- is consistent with that of the parent.
2616 Par_Discr : constant Entity_Id :=
2617 Get_Reference_Discriminant (Par_Type);
2618 Cur_Discr : constant Entity_Id :=
2619 Get_Reference_Discriminant (Prev);
2621 if Corresponding_Discriminant (Cur_Discr) /= Par_Discr then
2622 Error_Msg_N ("aspect incosistent with that of parent", N);
2628 -- TBD : other nonoverridable aspects.
2629 end Check_Nonoverridable_Aspects;
2631 ------------------------------------
2632 -- Check_Ops_From_Incomplete_Type --
2633 ------------------------------------
2635 procedure Check_Ops_From_Incomplete_Type is
2642 and then Ekind (Prev) = E_Incomplete_Type
2643 and then Is_Tagged_Type (Prev)
2644 and then Is_Tagged_Type (T)
2646 Elmt := First_Elmt (Primitive_Operations (Prev));
2647 while Present (Elmt) loop
2650 Formal := First_Formal (Op);
2651 while Present (Formal) loop
2652 if Etype (Formal) = Prev then
2653 Set_Etype (Formal, T);
2656 Next_Formal (Formal);
2659 if Etype (Op) = Prev then
2666 end Check_Ops_From_Incomplete_Type;
2668 -- Start of processing for Analyze_Full_Type_Declaration
2671 Prev := Find_Type_Name (N);
2673 -- The full view, if present, now points to the current type. If there
2674 -- is an incomplete partial view, set a link to it, to simplify the
2675 -- retrieval of primitive operations of the type.
2677 -- Ada 2005 (AI-50217): If the type was previously decorated when
2678 -- imported through a LIMITED WITH clause, it appears as incomplete
2679 -- but has no full view.
2681 if Ekind (Prev) = E_Incomplete_Type
2682 and then Present (Full_View (Prev))
2684 T := Full_View (Prev);
2685 Set_Incomplete_View (N, Parent (Prev));
2690 Set_Is_Pure (T, Is_Pure (Current_Scope));
2692 -- We set the flag Is_First_Subtype here. It is needed to set the
2693 -- corresponding flag for the Implicit class-wide-type created
2694 -- during tagged types processing.
2696 Set_Is_First_Subtype (T, True);
2698 -- Only composite types other than array types are allowed to have
2703 -- For derived types, the rule will be checked once we've figured
2704 -- out the parent type.
2706 when N_Derived_Type_Definition =>
2709 -- For record types, discriminants are allowed, unless we are in
2712 when N_Record_Definition =>
2713 if Present (Discriminant_Specifications (N)) then
2714 Check_SPARK_05_Restriction
2715 ("discriminant type is not allowed",
2717 (First (Discriminant_Specifications (N))));
2721 if Present (Discriminant_Specifications (N)) then
2723 ("elementary or array type cannot have discriminants",
2725 (First (Discriminant_Specifications (N))));
2729 -- Elaborate the type definition according to kind, and generate
2730 -- subsidiary (implicit) subtypes where needed. We skip this if it was
2731 -- already done (this happens during the reanalysis that follows a call
2732 -- to the high level optimizer).
2734 if not Analyzed (T) then
2738 when N_Access_To_Subprogram_Definition =>
2739 Access_Subprogram_Declaration (T, Def);
2741 -- If this is a remote access to subprogram, we must create the
2742 -- equivalent fat pointer type, and related subprograms.
2745 Process_Remote_AST_Declaration (N);
2748 -- Validate categorization rule against access type declaration
2749 -- usually a violation in Pure unit, Shared_Passive unit.
2751 Validate_Access_Type_Declaration (T, N);
2753 when N_Access_To_Object_Definition =>
2754 Access_Type_Declaration (T, Def);
2756 -- Validate categorization rule against access type declaration
2757 -- usually a violation in Pure unit, Shared_Passive unit.
2759 Validate_Access_Type_Declaration (T, N);
2761 -- If we are in a Remote_Call_Interface package and define a
2762 -- RACW, then calling stubs and specific stream attributes
2766 and then Is_Remote_Access_To_Class_Wide_Type (Def_Id)
2768 Add_RACW_Features (Def_Id);
2771 when N_Array_Type_Definition =>
2772 Array_Type_Declaration (T, Def);
2774 when N_Derived_Type_Definition =>
2775 Derived_Type_Declaration (T, N, T /= Def_Id);
2777 when N_Enumeration_Type_Definition =>
2778 Enumeration_Type_Declaration (T, Def);
2780 when N_Floating_Point_Definition =>
2781 Floating_Point_Type_Declaration (T, Def);
2783 when N_Decimal_Fixed_Point_Definition =>
2784 Decimal_Fixed_Point_Type_Declaration (T, Def);
2786 when N_Ordinary_Fixed_Point_Definition =>
2787 Ordinary_Fixed_Point_Type_Declaration (T, Def);
2789 when N_Signed_Integer_Type_Definition =>
2790 Signed_Integer_Type_Declaration (T, Def);
2792 when N_Modular_Type_Definition =>
2793 Modular_Type_Declaration (T, Def);
2795 when N_Record_Definition =>
2796 Record_Type_Declaration (T, N, Prev);
2798 -- If declaration has a parse error, nothing to elaborate.
2804 raise Program_Error;
2809 if Etype (T) = Any_Type then
2813 -- Controlled type is not allowed in SPARK
2815 if Is_Visibly_Controlled (T) then
2816 Check_SPARK_05_Restriction ("controlled type is not allowed", N);
2819 -- A type declared within a Ghost region is automatically Ghost
2820 -- (SPARK RM 6.9(2)).
2822 if Ghost_Mode > None then
2823 Set_Is_Ghost_Entity (T);
2826 -- Some common processing for all types
2828 Set_Depends_On_Private (T, Has_Private_Component (T));
2829 Check_Ops_From_Incomplete_Type;
2831 -- Both the declared entity, and its anonymous base type if one was
2832 -- created, need freeze nodes allocated.
2835 B : constant Entity_Id := Base_Type (T);
2838 -- In the case where the base type differs from the first subtype, we
2839 -- pre-allocate a freeze node, and set the proper link to the first
2840 -- subtype. Freeze_Entity will use this preallocated freeze node when
2841 -- it freezes the entity.
2843 -- This does not apply if the base type is a generic type, whose
2844 -- declaration is independent of the current derived definition.
2846 if B /= T and then not Is_Generic_Type (B) then
2847 Ensure_Freeze_Node (B);
2848 Set_First_Subtype_Link (Freeze_Node (B), T);
2851 -- A type that is imported through a limited_with clause cannot
2852 -- generate any code, and thus need not be frozen. However, an access
2853 -- type with an imported designated type needs a finalization list,
2854 -- which may be referenced in some other package that has non-limited
2855 -- visibility on the designated type. Thus we must create the
2856 -- finalization list at the point the access type is frozen, to
2857 -- prevent unsatisfied references at link time.
2859 if not From_Limited_With (T) or else Is_Access_Type (T) then
2860 Set_Has_Delayed_Freeze (T);
2864 -- Case where T is the full declaration of some private type which has
2865 -- been swapped in Defining_Identifier (N).
2867 if T /= Def_Id and then Is_Private_Type (Def_Id) then
2868 Process_Full_View (N, T, Def_Id);
2870 -- Record the reference. The form of this is a little strange, since
2871 -- the full declaration has been swapped in. So the first parameter
2872 -- here represents the entity to which a reference is made which is
2873 -- the "real" entity, i.e. the one swapped in, and the second
2874 -- parameter provides the reference location.
2876 -- Also, we want to kill Has_Pragma_Unreferenced temporarily here
2877 -- since we don't want a complaint about the full type being an
2878 -- unwanted reference to the private type
2881 B : constant Boolean := Has_Pragma_Unreferenced (T);
2883 Set_Has_Pragma_Unreferenced (T, False);
2884 Generate_Reference (T, T, 'c');
2885 Set_Has_Pragma_Unreferenced (T, B);
2888 Set_Completion_Referenced (Def_Id);
2890 -- For completion of incomplete type, process incomplete dependents
2891 -- and always mark the full type as referenced (it is the incomplete
2892 -- type that we get for any real reference).
2894 elsif Ekind (Prev) = E_Incomplete_Type then
2895 Process_Incomplete_Dependents (N, T, Prev);
2896 Generate_Reference (Prev, Def_Id, 'c');
2897 Set_Completion_Referenced (Def_Id);
2899 -- If not private type or incomplete type completion, this is a real
2900 -- definition of a new entity, so record it.
2903 Generate_Definition (Def_Id);
2906 -- Propagate any pending access types whose finalization masters need to
2907 -- be fully initialized from the partial to the full view. Guard against
2908 -- an illegal full view that remains unanalyzed.
2910 if Is_Type (Def_Id) and then Is_Incomplete_Or_Private_Type (Prev) then
2911 Set_Pending_Access_Types (Def_Id, Pending_Access_Types (Prev));
2914 if Chars (Scope (Def_Id)) = Name_System
2915 and then Chars (Def_Id) = Name_Address
2916 and then Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (N)))
2918 Set_Is_Descendant_Of_Address (Def_Id);
2919 Set_Is_Descendant_Of_Address (Base_Type (Def_Id));
2920 Set_Is_Descendant_Of_Address (Prev);
2923 Set_Optimize_Alignment_Flags (Def_Id);
2924 Check_Eliminated (Def_Id);
2926 -- If the declaration is a completion and aspects are present, apply
2927 -- them to the entity for the type which is currently the partial
2928 -- view, but which is the one that will be frozen.
2930 if Has_Aspects (N) then
2932 -- In most cases the partial view is a private type, and both views
2933 -- appear in different declarative parts. In the unusual case where
2934 -- the partial view is incomplete, perform the analysis on the
2935 -- full view, to prevent freezing anomalies with the corresponding
2936 -- class-wide type, which otherwise might be frozen before the
2937 -- dispatch table is built.
2940 and then Ekind (Prev) /= E_Incomplete_Type
2942 Analyze_Aspect_Specifications (N, Prev);
2947 Analyze_Aspect_Specifications (N, Def_Id);
2951 if Is_Derived_Type (Prev)
2952 and then Def_Id /= Prev
2954 Check_Nonoverridable_Aspects;
2956 end Analyze_Full_Type_Declaration;
2958 ----------------------------------
2959 -- Analyze_Incomplete_Type_Decl --
2960 ----------------------------------
2962 procedure Analyze_Incomplete_Type_Decl (N : Node_Id) is
2963 F : constant Boolean := Is_Pure (Current_Scope);
2967 Check_SPARK_05_Restriction ("incomplete type is not allowed", N);
2969 Generate_Definition (Defining_Identifier (N));
2971 -- Process an incomplete declaration. The identifier must not have been
2972 -- declared already in the scope. However, an incomplete declaration may
2973 -- appear in the private part of a package, for a private type that has
2974 -- already been declared.
2976 -- In this case, the discriminants (if any) must match
2978 T := Find_Type_Name (N);
2980 Set_Ekind (T, E_Incomplete_Type);
2981 Init_Size_Align (T);
2982 Set_Is_First_Subtype (T, True);
2985 -- An incomplete type declared within a Ghost region is automatically
2986 -- Ghost (SPARK RM 6.9(2)).
2988 if Ghost_Mode > None then
2989 Set_Is_Ghost_Entity (T);
2992 -- Ada 2005 (AI-326): Minimum decoration to give support to tagged
2993 -- incomplete types.
2995 if Tagged_Present (N) then
2996 Set_Is_Tagged_Type (T, True);
2997 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
2998 Make_Class_Wide_Type (T);
2999 Set_Direct_Primitive_Operations (T, New_Elmt_List);
3002 Set_Stored_Constraint (T, No_Elist);
3004 if Present (Discriminant_Specifications (N)) then
3006 Process_Discriminants (N);
3010 -- If the type has discriminants, nontrivial subtypes may be declared
3011 -- before the full view of the type. The full views of those subtypes
3012 -- will be built after the full view of the type.
3014 Set_Private_Dependents (T, New_Elmt_List);
3016 end Analyze_Incomplete_Type_Decl;
3018 -----------------------------------
3019 -- Analyze_Interface_Declaration --
3020 -----------------------------------
3022 procedure Analyze_Interface_Declaration (T : Entity_Id; Def : Node_Id) is
3023 CW : constant Entity_Id := Class_Wide_Type (T);
3026 Set_Is_Tagged_Type (T);
3027 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
3029 Set_Is_Limited_Record (T, Limited_Present (Def)
3030 or else Task_Present (Def)
3031 or else Protected_Present (Def)
3032 or else Synchronized_Present (Def));
3034 -- Type is abstract if full declaration carries keyword, or if previous
3035 -- partial view did.
3037 Set_Is_Abstract_Type (T);
3038 Set_Is_Interface (T);
3040 -- Type is a limited interface if it includes the keyword limited, task,
3041 -- protected, or synchronized.
3043 Set_Is_Limited_Interface
3044 (T, Limited_Present (Def)
3045 or else Protected_Present (Def)
3046 or else Synchronized_Present (Def)
3047 or else Task_Present (Def));
3049 Set_Interfaces (T, New_Elmt_List);
3050 Set_Direct_Primitive_Operations (T, New_Elmt_List);
3052 -- Complete the decoration of the class-wide entity if it was already
3053 -- built (i.e. during the creation of the limited view)
3055 if Present (CW) then
3056 Set_Is_Interface (CW);
3057 Set_Is_Limited_Interface (CW, Is_Limited_Interface (T));
3060 -- Check runtime support for synchronized interfaces
3062 if (Is_Task_Interface (T)
3063 or else Is_Protected_Interface (T)
3064 or else Is_Synchronized_Interface (T))
3065 and then not RTE_Available (RE_Select_Specific_Data)
3067 Error_Msg_CRT ("synchronized interfaces", T);
3069 end Analyze_Interface_Declaration;
3071 -----------------------------
3072 -- Analyze_Itype_Reference --
3073 -----------------------------
3075 -- Nothing to do. This node is placed in the tree only for the benefit of
3076 -- back end processing, and has no effect on the semantic processing.
3078 procedure Analyze_Itype_Reference (N : Node_Id) is
3080 pragma Assert (Is_Itype (Itype (N)));
3082 end Analyze_Itype_Reference;
3084 --------------------------------
3085 -- Analyze_Number_Declaration --
3086 --------------------------------
3088 procedure Analyze_Number_Declaration (N : Node_Id) is
3089 E : constant Node_Id := Expression (N);
3090 Id : constant Entity_Id := Defining_Identifier (N);
3091 Index : Interp_Index;
3096 Generate_Definition (Id);
3099 -- A number declared within a Ghost region is automatically Ghost
3100 -- (SPARK RM 6.9(2)).
3102 if Ghost_Mode > None then
3103 Set_Is_Ghost_Entity (Id);
3106 -- This is an optimization of a common case of an integer literal
3108 if Nkind (E) = N_Integer_Literal then
3109 Set_Is_Static_Expression (E, True);
3110 Set_Etype (E, Universal_Integer);
3112 Set_Etype (Id, Universal_Integer);
3113 Set_Ekind (Id, E_Named_Integer);
3114 Set_Is_Frozen (Id, True);
3118 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3120 -- Process expression, replacing error by integer zero, to avoid
3121 -- cascaded errors or aborts further along in the processing
3123 -- Replace Error by integer zero, which seems least likely to cause
3127 Rewrite (E, Make_Integer_Literal (Sloc (E), Uint_0));
3128 Set_Error_Posted (E);
3133 -- Verify that the expression is static and numeric. If
3134 -- the expression is overloaded, we apply the preference
3135 -- rule that favors root numeric types.
3137 if not Is_Overloaded (E) then
3139 if Has_Dynamic_Predicate_Aspect (T) then
3141 ("subtype has dynamic predicate, "
3142 & "not allowed in number declaration", N);
3148 Get_First_Interp (E, Index, It);
3149 while Present (It.Typ) loop
3150 if (Is_Integer_Type (It.Typ) or else Is_Real_Type (It.Typ))
3151 and then (Scope (Base_Type (It.Typ))) = Standard_Standard
3153 if T = Any_Type then
3156 elsif It.Typ = Universal_Real
3158 It.Typ = Universal_Integer
3160 -- Choose universal interpretation over any other
3167 Get_Next_Interp (Index, It);
3171 if Is_Integer_Type (T) then
3173 Set_Etype (Id, Universal_Integer);
3174 Set_Ekind (Id, E_Named_Integer);
3176 elsif Is_Real_Type (T) then
3178 -- Because the real value is converted to universal_real, this is a
3179 -- legal context for a universal fixed expression.
3181 if T = Universal_Fixed then
3183 Loc : constant Source_Ptr := Sloc (N);
3184 Conv : constant Node_Id := Make_Type_Conversion (Loc,
3186 New_Occurrence_Of (Universal_Real, Loc),
3187 Expression => Relocate_Node (E));
3194 elsif T = Any_Fixed then
3195 Error_Msg_N ("illegal context for mixed mode operation", E);
3197 -- Expression is of the form : universal_fixed * integer. Try to
3198 -- resolve as universal_real.
3200 T := Universal_Real;
3205 Set_Etype (Id, Universal_Real);
3206 Set_Ekind (Id, E_Named_Real);
3209 Wrong_Type (E, Any_Numeric);
3213 Set_Ekind (Id, E_Constant);
3214 Set_Never_Set_In_Source (Id, True);
3215 Set_Is_True_Constant (Id, True);
3219 if Nkind_In (E, N_Integer_Literal, N_Real_Literal) then
3220 Set_Etype (E, Etype (Id));
3223 if not Is_OK_Static_Expression (E) then
3224 Flag_Non_Static_Expr
3225 ("non-static expression used in number declaration!", E);
3226 Rewrite (E, Make_Integer_Literal (Sloc (N), 1));
3227 Set_Etype (E, Any_Type);
3230 Analyze_Dimension (N);
3231 end Analyze_Number_Declaration;
3233 --------------------------------
3234 -- Analyze_Object_Declaration --
3235 --------------------------------
3237 procedure Analyze_Object_Declaration (N : Node_Id) is
3238 Loc : constant Source_Ptr := Sloc (N);
3239 Id : constant Entity_Id := Defining_Identifier (N);
3243 E : Node_Id := Expression (N);
3244 -- E is set to Expression (N) throughout this routine. When
3245 -- Expression (N) is modified, E is changed accordingly.
3247 Prev_Entity : Entity_Id := Empty;
3249 function Count_Tasks (T : Entity_Id) return Uint;
3250 -- This function is called when a non-generic library level object of a
3251 -- task type is declared. Its function is to count the static number of
3252 -- tasks declared within the type (it is only called if Has_Task is set
3253 -- for T). As a side effect, if an array of tasks with non-static bounds
3254 -- or a variant record type is encountered, Check_Restriction is called
3255 -- indicating the count is unknown.
3257 function Delayed_Aspect_Present return Boolean;
3258 -- If the declaration has an expression that is an aggregate, and it
3259 -- has aspects that require delayed analysis, the resolution of the
3260 -- aggregate must be deferred to the freeze point of the objet. This
3261 -- special processing was created for address clauses, but it must
3262 -- also apply to Alignment. This must be done before the aspect
3263 -- specifications are analyzed because we must handle the aggregate
3264 -- before the analysis of the object declaration is complete.
3266 -- Any other relevant delayed aspects on object declarations ???
3272 function Count_Tasks (T : Entity_Id) return Uint is
3278 if Is_Task_Type (T) then
3281 elsif Is_Record_Type (T) then
3282 if Has_Discriminants (T) then
3283 Check_Restriction (Max_Tasks, N);
3288 C := First_Component (T);
3289 while Present (C) loop
3290 V := V + Count_Tasks (Etype (C));
3297 elsif Is_Array_Type (T) then
3298 X := First_Index (T);
3299 V := Count_Tasks (Component_Type (T));
3300 while Present (X) loop
3303 if not Is_OK_Static_Subtype (C) then
3304 Check_Restriction (Max_Tasks, N);
3307 V := V * (UI_Max (Uint_0,
3308 Expr_Value (Type_High_Bound (C)) -
3309 Expr_Value (Type_Low_Bound (C)) + Uint_1));
3322 ----------------------------
3323 -- Delayed_Aspect_Present --
3324 ----------------------------
3326 function Delayed_Aspect_Present return Boolean is
3331 if Present (Aspect_Specifications (N)) then
3332 A := First (Aspect_Specifications (N));
3333 A_Id := Get_Aspect_Id (Chars (Identifier (A)));
3334 while Present (A) loop
3335 if A_Id = Aspect_Alignment or else A_Id = Aspect_Address then
3344 end Delayed_Aspect_Present;
3348 Save_Ghost_Mode : constant Ghost_Mode_Type := Ghost_Mode;
3349 Related_Id : Entity_Id;
3351 -- Start of processing for Analyze_Object_Declaration
3354 -- There are three kinds of implicit types generated by an
3355 -- object declaration:
3357 -- 1. Those generated by the original Object Definition
3359 -- 2. Those generated by the Expression
3361 -- 3. Those used to constrain the Object Definition with the
3362 -- expression constraints when the definition is unconstrained.
3364 -- They must be generated in this order to avoid order of elaboration
3365 -- issues. Thus the first step (after entering the name) is to analyze
3366 -- the object definition.
3368 if Constant_Present (N) then
3369 Prev_Entity := Current_Entity_In_Scope (Id);
3371 if Present (Prev_Entity)
3373 -- If the homograph is an implicit subprogram, it is overridden
3374 -- by the current declaration.
3376 ((Is_Overloadable (Prev_Entity)
3377 and then Is_Inherited_Operation (Prev_Entity))
3379 -- The current object is a discriminal generated for an entry
3380 -- family index. Even though the index is a constant, in this
3381 -- particular context there is no true constant redeclaration.
3382 -- Enter_Name will handle the visibility.
3385 (Is_Discriminal (Id)
3386 and then Ekind (Discriminal_Link (Id)) =
3387 E_Entry_Index_Parameter)
3389 -- The current object is the renaming for a generic declared
3390 -- within the instance.
3393 (Ekind (Prev_Entity) = E_Package
3394 and then Nkind (Parent (Prev_Entity)) =
3395 N_Package_Renaming_Declaration
3396 and then not Comes_From_Source (Prev_Entity)
3398 Is_Generic_Instance (Renamed_Entity (Prev_Entity))))
3400 Prev_Entity := Empty;
3404 -- The object declaration is Ghost when it is subject to pragma Ghost or
3405 -- completes a deferred Ghost constant. Set the mode now to ensure that
3406 -- any nodes generated during analysis and expansion are properly marked
3409 Set_Ghost_Mode (N, Prev_Entity);
3411 if Present (Prev_Entity) then
3412 Constant_Redeclaration (Id, N, T);
3414 Generate_Reference (Prev_Entity, Id, 'c');
3415 Set_Completion_Referenced (Id);
3417 if Error_Posted (N) then
3419 -- Type mismatch or illegal redeclaration, Do not analyze
3420 -- expression to avoid cascaded errors.
3422 T := Find_Type_Of_Object (Object_Definition (N), N);
3424 Set_Ekind (Id, E_Variable);
3428 -- In the normal case, enter identifier at the start to catch premature
3429 -- usage in the initialization expression.
3432 Generate_Definition (Id);
3435 Mark_Coextensions (N, Object_Definition (N));
3437 T := Find_Type_Of_Object (Object_Definition (N), N);
3439 if Nkind (Object_Definition (N)) = N_Access_Definition
3441 (Access_To_Subprogram_Definition (Object_Definition (N)))
3442 and then Protected_Present
3443 (Access_To_Subprogram_Definition (Object_Definition (N)))
3445 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
3448 if Error_Posted (Id) then
3450 Set_Ekind (Id, E_Variable);
3455 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
3456 -- out some static checks
3458 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
3460 -- In case of aggregates we must also take care of the correct
3461 -- initialization of nested aggregates bug this is done at the
3462 -- point of the analysis of the aggregate (see sem_aggr.adb).
3464 if Present (Expression (N))
3465 and then Nkind (Expression (N)) = N_Aggregate
3471 Save_Typ : constant Entity_Id := Etype (Id);
3473 Set_Etype (Id, T); -- Temp. decoration for static checks
3474 Null_Exclusion_Static_Checks (N);
3475 Set_Etype (Id, Save_Typ);
3480 -- Object is marked pure if it is in a pure scope
3482 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3484 -- If deferred constant, make sure context is appropriate. We detect
3485 -- a deferred constant as a constant declaration with no expression.
3486 -- A deferred constant can appear in a package body if its completion
3487 -- is by means of an interface pragma.
3489 if Constant_Present (N) and then No (E) then
3491 -- A deferred constant may appear in the declarative part of the
3492 -- following constructs:
3496 -- extended return statements
3499 -- subprogram bodies
3502 -- When declared inside a package spec, a deferred constant must be
3503 -- completed by a full constant declaration or pragma Import. In all
3504 -- other cases, the only proper completion is pragma Import. Extended
3505 -- return statements are flagged as invalid contexts because they do
3506 -- not have a declarative part and so cannot accommodate the pragma.
3508 if Ekind (Current_Scope) = E_Return_Statement then
3510 ("invalid context for deferred constant declaration (RM 7.4)",
3513 ("\declaration requires an initialization expression",
3515 Set_Constant_Present (N, False);
3517 -- In Ada 83, deferred constant must be of private type
3519 elsif not Is_Private_Type (T) then
3520 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
3522 ("(Ada 83) deferred constant must be private type", N);
3526 -- If not a deferred constant, then the object declaration freezes
3527 -- its type, unless the object is of an anonymous type and has delayed
3528 -- aspects. In that case the type is frozen when the object itself is.
3531 Check_Fully_Declared (T, N);
3533 if Has_Delayed_Aspects (Id)
3534 and then Is_Array_Type (T)
3535 and then Is_Itype (T)
3537 Set_Has_Delayed_Freeze (T);
3539 Freeze_Before (N, T);
3543 -- If the object was created by a constrained array definition, then
3544 -- set the link in both the anonymous base type and anonymous subtype
3545 -- that are built to represent the array type to point to the object.
3547 if Nkind (Object_Definition (Declaration_Node (Id))) =
3548 N_Constrained_Array_Definition
3550 Set_Related_Array_Object (T, Id);
3551 Set_Related_Array_Object (Base_Type (T), Id);
3554 -- Special checks for protected objects not at library level
3556 if Is_Protected_Type (T)
3557 and then not Is_Library_Level_Entity (Id)
3559 Check_Restriction (No_Local_Protected_Objects, Id);
3561 -- Protected objects with interrupt handlers must be at library level
3563 -- Ada 2005: This test is not needed (and the corresponding clause
3564 -- in the RM is removed) because accessibility checks are sufficient
3565 -- to make handlers not at the library level illegal.
3567 -- AI05-0303: The AI is in fact a binding interpretation, and thus
3568 -- applies to the '95 version of the language as well.
3570 if Has_Interrupt_Handler (T) and then Ada_Version < Ada_95 then
3572 ("interrupt object can only be declared at library level", Id);
3576 -- The actual subtype of the object is the nominal subtype, unless
3577 -- the nominal one is unconstrained and obtained from the expression.
3581 -- These checks should be performed before the initialization expression
3582 -- is considered, so that the Object_Definition node is still the same
3583 -- as in source code.
3585 -- In SPARK, the nominal subtype is always given by a subtype mark
3586 -- and must not be unconstrained. (The only exception to this is the
3587 -- acceptance of declarations of constants of type String.)
3589 if not Nkind_In (Object_Definition (N), N_Expanded_Name, N_Identifier)
3591 Check_SPARK_05_Restriction
3592 ("subtype mark required", Object_Definition (N));
3594 elsif Is_Array_Type (T)
3595 and then not Is_Constrained (T)
3596 and then T /= Standard_String
3598 Check_SPARK_05_Restriction
3599 ("subtype mark of constrained type expected",
3600 Object_Definition (N));
3603 -- There are no aliased objects in SPARK
3605 if Aliased_Present (N) then
3606 Check_SPARK_05_Restriction ("aliased object is not allowed", N);
3609 -- Process initialization expression if present and not in error
3611 if Present (E) and then E /= Error then
3613 -- Generate an error in case of CPP class-wide object initialization.
3614 -- Required because otherwise the expansion of the class-wide
3615 -- assignment would try to use 'size to initialize the object
3616 -- (primitive that is not available in CPP tagged types).
3618 if Is_Class_Wide_Type (Act_T)
3620 (Is_CPP_Class (Root_Type (Etype (Act_T)))
3622 (Present (Full_View (Root_Type (Etype (Act_T))))
3624 Is_CPP_Class (Full_View (Root_Type (Etype (Act_T))))))
3627 ("predefined assignment not available for 'C'P'P tagged types",
3631 Mark_Coextensions (N, E);
3634 -- In case of errors detected in the analysis of the expression,
3635 -- decorate it with the expected type to avoid cascaded errors
3637 if No (Etype (E)) then
3641 -- If an initialization expression is present, then we set the
3642 -- Is_True_Constant flag. It will be reset if this is a variable
3643 -- and it is indeed modified.
3645 Set_Is_True_Constant (Id, True);
3647 -- If we are analyzing a constant declaration, set its completion
3648 -- flag after analyzing and resolving the expression.
3650 if Constant_Present (N) then
3651 Set_Has_Completion (Id);
3654 -- Set type and resolve (type may be overridden later on). Note:
3655 -- Ekind (Id) must still be E_Void at this point so that incorrect
3656 -- early usage within E is properly diagnosed.
3660 -- If the expression is an aggregate we must look ahead to detect
3661 -- the possible presence of an address clause, and defer resolution
3662 -- and expansion of the aggregate to the freeze point of the entity.
3664 -- This is not always legal because the aggregate may contain other
3665 -- references that need freezing, e.g. references to other entities
3666 -- with address clauses. In any case, when compiling with -gnatI the
3667 -- presence of the address clause must be ignored.
3669 if Comes_From_Source (N)
3670 and then Expander_Active
3671 and then Nkind (E) = N_Aggregate
3673 ((Present (Following_Address_Clause (N))
3674 and then not Ignore_Rep_Clauses)
3675 or else Delayed_Aspect_Present)
3683 -- No further action needed if E is a call to an inlined function
3684 -- which returns an unconstrained type and it has been expanded into
3685 -- a procedure call. In that case N has been replaced by an object
3686 -- declaration without initializing expression and it has been
3687 -- analyzed (see Expand_Inlined_Call).
3689 if Back_End_Inlining
3690 and then Expander_Active
3691 and then Nkind (E) = N_Function_Call
3692 and then Nkind (Name (E)) in N_Has_Entity
3693 and then Is_Inlined (Entity (Name (E)))
3694 and then not Is_Constrained (Etype (E))
3695 and then Analyzed (N)
3696 and then No (Expression (N))
3698 Ghost_Mode := Save_Ghost_Mode;
3702 -- If E is null and has been replaced by an N_Raise_Constraint_Error
3703 -- node (which was marked already-analyzed), we need to set the type
3704 -- to something other than Any_Access in order to keep gigi happy.
3706 if Etype (E) = Any_Access then
3710 -- If the object is an access to variable, the initialization
3711 -- expression cannot be an access to constant.
3713 if Is_Access_Type (T)
3714 and then not Is_Access_Constant (T)
3715 and then Is_Access_Type (Etype (E))
3716 and then Is_Access_Constant (Etype (E))
3719 ("access to variable cannot be initialized with an "
3720 & "access-to-constant expression", E);
3723 if not Assignment_OK (N) then
3724 Check_Initialization (T, E);
3727 Check_Unset_Reference (E);
3729 -- If this is a variable, then set current value. If this is a
3730 -- declared constant of a scalar type with a static expression,
3731 -- indicate that it is always valid.
3733 if not Constant_Present (N) then
3734 if Compile_Time_Known_Value (E) then
3735 Set_Current_Value (Id, E);
3738 elsif Is_Scalar_Type (T) and then Is_OK_Static_Expression (E) then
3739 Set_Is_Known_Valid (Id);
3742 -- Deal with setting of null flags
3744 if Is_Access_Type (T) then
3745 if Known_Non_Null (E) then
3746 Set_Is_Known_Non_Null (Id, True);
3747 elsif Known_Null (E) and then not Can_Never_Be_Null (Id) then
3748 Set_Is_Known_Null (Id, True);
3752 -- Check incorrect use of dynamically tagged expressions
3754 if Is_Tagged_Type (T) then
3755 Check_Dynamically_Tagged_Expression
3761 Apply_Scalar_Range_Check (E, T);
3762 Apply_Static_Length_Check (E, T);
3764 if Nkind (Original_Node (N)) = N_Object_Declaration
3765 and then Comes_From_Source (Original_Node (N))
3767 -- Only call test if needed
3769 and then Restriction_Check_Required (SPARK_05)
3770 and then not Is_SPARK_05_Initialization_Expr (Original_Node (E))
3772 Check_SPARK_05_Restriction
3773 ("initialization expression is not appropriate", E);
3776 -- A formal parameter of a specific tagged type whose related
3777 -- subprogram is subject to pragma Extensions_Visible with value
3778 -- "False" cannot be implicitly converted to a class-wide type by
3779 -- means of an initialization expression (SPARK RM 6.1.7(3)). Do
3780 -- not consider internally generated expressions.
3782 if Is_Class_Wide_Type (T)
3783 and then Comes_From_Source (E)
3784 and then Is_EVF_Expression (E)
3787 ("formal parameter with Extensions_Visible False cannot be "
3788 & "implicitly converted to class-wide type", E);
3792 -- If the No_Streams restriction is set, check that the type of the
3793 -- object is not, and does not contain, any subtype derived from
3794 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
3795 -- Has_Stream just for efficiency reasons. There is no point in
3796 -- spending time on a Has_Stream check if the restriction is not set.
3798 if Restriction_Check_Required (No_Streams) then
3799 if Has_Stream (T) then
3800 Check_Restriction (No_Streams, N);
3804 -- Deal with predicate check before we start to do major rewriting. It
3805 -- is OK to initialize and then check the initialized value, since the
3806 -- object goes out of scope if we get a predicate failure. Note that we
3807 -- do this in the analyzer and not the expander because the analyzer
3808 -- does some substantial rewriting in some cases.
3810 -- We need a predicate check if the type has predicates, and if either
3811 -- there is an initializing expression, or for default initialization
3812 -- when we have at least one case of an explicit default initial value
3813 -- and then this is not an internal declaration whose initialization
3814 -- comes later (as for an aggregate expansion).
3816 if not Suppress_Assignment_Checks (N)
3817 and then Present (Predicate_Function (T))
3818 and then not No_Initialization (N)
3822 Is_Partially_Initialized_Type (T, Include_Implicit => False))
3824 -- If the type has a static predicate and the expression is known at
3825 -- compile time, see if the expression satisfies the predicate.
3828 Check_Expression_Against_Static_Predicate (E, T);
3832 Make_Predicate_Check (T, New_Occurrence_Of (Id, Loc)));
3835 -- Case of unconstrained type
3837 if not Is_Definite_Subtype (T) then
3839 -- In SPARK, a declaration of unconstrained type is allowed
3840 -- only for constants of type string.
3842 if Is_String_Type (T) and then not Constant_Present (N) then
3843 Check_SPARK_05_Restriction
3844 ("declaration of object of unconstrained type not allowed", N);
3847 -- Nothing to do in deferred constant case
3849 if Constant_Present (N) and then No (E) then
3852 -- Case of no initialization present
3855 if No_Initialization (N) then
3858 elsif Is_Class_Wide_Type (T) then
3860 ("initialization required in class-wide declaration ", N);
3864 ("unconstrained subtype not allowed (need initialization)",
3865 Object_Definition (N));
3867 if Is_Record_Type (T) and then Has_Discriminants (T) then
3869 ("\provide initial value or explicit discriminant values",
3870 Object_Definition (N));
3873 ("\or give default discriminant values for type&",
3874 Object_Definition (N), T);
3876 elsif Is_Array_Type (T) then
3878 ("\provide initial value or explicit array bounds",
3879 Object_Definition (N));
3883 -- Case of initialization present but in error. Set initial
3884 -- expression as absent (but do not make above complaints)
3886 elsif E = Error then
3887 Set_Expression (N, Empty);
3890 -- Case of initialization present
3893 -- Check restrictions in Ada 83
3895 if not Constant_Present (N) then
3897 -- Unconstrained variables not allowed in Ada 83 mode
3899 if Ada_Version = Ada_83
3900 and then Comes_From_Source (Object_Definition (N))
3903 ("(Ada 83) unconstrained variable not allowed",
3904 Object_Definition (N));
3908 -- Now we constrain the variable from the initializing expression
3910 -- If the expression is an aggregate, it has been expanded into
3911 -- individual assignments. Retrieve the actual type from the
3912 -- expanded construct.
3914 if Is_Array_Type (T)
3915 and then No_Initialization (N)
3916 and then Nkind (Original_Node (E)) = N_Aggregate
3920 -- In case of class-wide interface object declarations we delay
3921 -- the generation of the equivalent record type declarations until
3922 -- its expansion because there are cases in they are not required.
3924 elsif Is_Interface (T) then
3927 -- In GNATprove mode, Expand_Subtype_From_Expr does nothing. Thus,
3928 -- we should prevent the generation of another Itype with the
3929 -- same name as the one already generated, or we end up with
3930 -- two identical types in GNATprove.
3932 elsif GNATprove_Mode then
3935 -- If the type is an unchecked union, no subtype can be built from
3936 -- the expression. Rewrite declaration as a renaming, which the
3937 -- back-end can handle properly. This is a rather unusual case,
3938 -- because most unchecked_union declarations have default values
3939 -- for discriminants and are thus not indefinite.
3941 elsif Is_Unchecked_Union (T) then
3942 if Constant_Present (N) or else Nkind (E) = N_Function_Call then
3943 Set_Ekind (Id, E_Constant);
3945 Set_Ekind (Id, E_Variable);
3948 -- An object declared within a Ghost region is automatically
3949 -- Ghost (SPARK RM 6.9(2)).
3951 if Ghost_Mode > None then
3952 Set_Is_Ghost_Entity (Id);
3954 -- The Ghost policy in effect at the point of declaration
3955 -- and at the point of completion must match
3956 -- (SPARK RM 6.9(14)).
3958 if Present (Prev_Entity)
3959 and then Is_Ghost_Entity (Prev_Entity)
3961 Check_Ghost_Completion (Prev_Entity, Id);
3966 Make_Object_Renaming_Declaration (Loc,
3967 Defining_Identifier => Id,
3968 Subtype_Mark => New_Occurrence_Of (T, Loc),
3971 Set_Renamed_Object (Id, E);
3972 Freeze_Before (N, T);
3975 Ghost_Mode := Save_Ghost_Mode;
3979 -- Ensure that the generated subtype has a unique external name
3980 -- when the related object is public. This guarantees that the
3981 -- subtype and its bounds will not be affected by switches or
3982 -- pragmas that may offset the internal counter due to extra
3985 if Is_Public (Id) then
3988 Related_Id := Empty;
3991 Expand_Subtype_From_Expr
3994 Subtype_Indic => Object_Definition (N),
3996 Related_Id => Related_Id);
3998 Act_T := Find_Type_Of_Object (Object_Definition (N), N);
4001 Set_Is_Constr_Subt_For_U_Nominal (Act_T);
4003 if Aliased_Present (N) then
4004 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
4007 Freeze_Before (N, Act_T);
4008 Freeze_Before (N, T);
4011 elsif Is_Array_Type (T)
4012 and then No_Initialization (N)
4013 and then Nkind (Original_Node (E)) = N_Aggregate
4015 if not Is_Entity_Name (Object_Definition (N)) then
4017 Check_Compile_Time_Size (Act_T);
4019 if Aliased_Present (N) then
4020 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
4024 -- When the given object definition and the aggregate are specified
4025 -- independently, and their lengths might differ do a length check.
4026 -- This cannot happen if the aggregate is of the form (others =>...)
4028 if not Is_Constrained (T) then
4031 elsif Nkind (E) = N_Raise_Constraint_Error then
4033 -- Aggregate is statically illegal. Place back in declaration
4035 Set_Expression (N, E);
4036 Set_No_Initialization (N, False);
4038 elsif T = Etype (E) then
4041 elsif Nkind (E) = N_Aggregate
4042 and then Present (Component_Associations (E))
4043 and then Present (Choices (First (Component_Associations (E))))
4044 and then Nkind (First
4045 (Choices (First (Component_Associations (E))))) = N_Others_Choice
4050 Apply_Length_Check (E, T);
4053 -- If the type is limited unconstrained with defaulted discriminants and
4054 -- there is no expression, then the object is constrained by the
4055 -- defaults, so it is worthwhile building the corresponding subtype.
4057 elsif (Is_Limited_Record (T) or else Is_Concurrent_Type (T))
4058 and then not Is_Constrained (T)
4059 and then Has_Discriminants (T)
4062 Act_T := Build_Default_Subtype (T, N);
4064 -- Ada 2005: A limited object may be initialized by means of an
4065 -- aggregate. If the type has default discriminants it has an
4066 -- unconstrained nominal type, Its actual subtype will be obtained
4067 -- from the aggregate, and not from the default discriminants.
4072 Rewrite (Object_Definition (N), New_Occurrence_Of (Act_T, Loc));
4074 elsif Nkind (E) = N_Function_Call
4075 and then Constant_Present (N)
4076 and then Has_Unconstrained_Elements (Etype (E))
4078 -- The back-end has problems with constants of a discriminated type
4079 -- with defaults, if the initial value is a function call. We
4080 -- generate an intermediate temporary that will receive a reference
4081 -- to the result of the call. The initialization expression then
4082 -- becomes a dereference of that temporary.
4084 Remove_Side_Effects (E);
4086 -- If this is a constant declaration of an unconstrained type and
4087 -- the initialization is an aggregate, we can use the subtype of the
4088 -- aggregate for the declared entity because it is immutable.
4090 elsif not Is_Constrained (T)
4091 and then Has_Discriminants (T)
4092 and then Constant_Present (N)
4093 and then not Has_Unchecked_Union (T)
4094 and then Nkind (E) = N_Aggregate
4099 -- Check No_Wide_Characters restriction
4101 Check_Wide_Character_Restriction (T, Object_Definition (N));
4103 -- Indicate this is not set in source. Certainly true for constants, and
4104 -- true for variables so far (will be reset for a variable if and when
4105 -- we encounter a modification in the source).
4107 Set_Never_Set_In_Source (Id);
4109 -- Now establish the proper kind and type of the object
4111 if Constant_Present (N) then
4112 Set_Ekind (Id, E_Constant);
4113 Set_Is_True_Constant (Id);
4116 Set_Ekind (Id, E_Variable);
4118 -- A variable is set as shared passive if it appears in a shared
4119 -- passive package, and is at the outer level. This is not done for
4120 -- entities generated during expansion, because those are always
4121 -- manipulated locally.
4123 if Is_Shared_Passive (Current_Scope)
4124 and then Is_Library_Level_Entity (Id)
4125 and then Comes_From_Source (Id)
4127 Set_Is_Shared_Passive (Id);
4128 Check_Shared_Var (Id, T, N);
4131 -- Set Has_Initial_Value if initializing expression present. Note
4132 -- that if there is no initializing expression, we leave the state
4133 -- of this flag unchanged (usually it will be False, but notably in
4134 -- the case of exception choice variables, it will already be true).
4137 Set_Has_Initial_Value (Id);
4141 -- Initialize alignment and size and capture alignment setting
4143 Init_Alignment (Id);
4145 Set_Optimize_Alignment_Flags (Id);
4147 -- An object declared within a Ghost region is automatically Ghost
4148 -- (SPARK RM 6.9(2)).
4150 if Ghost_Mode > None
4151 or else (Present (Prev_Entity) and then Is_Ghost_Entity (Prev_Entity))
4153 Set_Is_Ghost_Entity (Id);
4155 -- The Ghost policy in effect at the point of declaration and at the
4156 -- point of completion must match (SPARK RM 6.9(14)).
4158 if Present (Prev_Entity) and then Is_Ghost_Entity (Prev_Entity) then
4159 Check_Ghost_Completion (Prev_Entity, Id);
4163 -- Deal with aliased case
4165 if Aliased_Present (N) then
4166 Set_Is_Aliased (Id);
4168 -- If the object is aliased and the type is unconstrained with
4169 -- defaulted discriminants and there is no expression, then the
4170 -- object is constrained by the defaults, so it is worthwhile
4171 -- building the corresponding subtype.
4173 -- Ada 2005 (AI-363): If the aliased object is discriminated and
4174 -- unconstrained, then only establish an actual subtype if the
4175 -- nominal subtype is indefinite. In definite cases the object is
4176 -- unconstrained in Ada 2005.
4179 and then Is_Record_Type (T)
4180 and then not Is_Constrained (T)
4181 and then Has_Discriminants (T)
4182 and then (Ada_Version < Ada_2005
4183 or else not Is_Definite_Subtype (T))
4185 Set_Actual_Subtype (Id, Build_Default_Subtype (T, N));
4189 -- Now we can set the type of the object
4191 Set_Etype (Id, Act_T);
4193 -- Non-constant object is marked to be treated as volatile if type is
4194 -- volatile and we clear the Current_Value setting that may have been
4195 -- set above. Doing so for constants isn't required and might interfere
4196 -- with possible uses of the object as a static expression in contexts
4197 -- incompatible with volatility (e.g. as a case-statement alternative).
4199 if Ekind (Id) /= E_Constant and then Treat_As_Volatile (Etype (Id)) then
4200 Set_Treat_As_Volatile (Id);
4201 Set_Current_Value (Id, Empty);
4204 -- Deal with controlled types
4206 if Has_Controlled_Component (Etype (Id))
4207 or else Is_Controlled (Etype (Id))
4209 if not Is_Library_Level_Entity (Id) then
4210 Check_Restriction (No_Nested_Finalization, N);
4212 Validate_Controlled_Object (Id);
4216 if Has_Task (Etype (Id)) then
4217 Check_Restriction (No_Tasking, N);
4219 -- Deal with counting max tasks
4221 -- Nothing to do if inside a generic
4223 if Inside_A_Generic then
4226 -- If library level entity, then count tasks
4228 elsif Is_Library_Level_Entity (Id) then
4229 Check_Restriction (Max_Tasks, N, Count_Tasks (Etype (Id)));
4231 -- If not library level entity, then indicate we don't know max
4232 -- tasks and also check task hierarchy restriction and blocking
4233 -- operation (since starting a task is definitely blocking).
4236 Check_Restriction (Max_Tasks, N);
4237 Check_Restriction (No_Task_Hierarchy, N);
4238 Check_Potentially_Blocking_Operation (N);
4241 -- A rather specialized test. If we see two tasks being declared
4242 -- of the same type in the same object declaration, and the task
4243 -- has an entry with an address clause, we know that program error
4244 -- will be raised at run time since we can't have two tasks with
4245 -- entries at the same address.
4247 if Is_Task_Type (Etype (Id)) and then More_Ids (N) then
4252 E := First_Entity (Etype (Id));
4253 while Present (E) loop
4254 if Ekind (E) = E_Entry
4255 and then Present (Get_Attribute_Definition_Clause
4256 (E, Attribute_Address))
4258 Error_Msg_Warn := SPARK_Mode /= On;
4260 ("more than one task with same entry address<<", N);
4261 Error_Msg_N ("\Program_Error [<<", N);
4263 Make_Raise_Program_Error (Loc,
4264 Reason => PE_Duplicated_Entry_Address));
4274 -- Some simple constant-propagation: if the expression is a constant
4275 -- string initialized with a literal, share the literal. This avoids
4279 and then Is_Entity_Name (E)
4280 and then Ekind (Entity (E)) = E_Constant
4281 and then Base_Type (Etype (E)) = Standard_String
4284 Val : constant Node_Id := Constant_Value (Entity (E));
4286 if Present (Val) and then Nkind (Val) = N_String_Literal then
4287 Rewrite (E, New_Copy (Val));
4292 -- Another optimization: if the nominal subtype is unconstrained and
4293 -- the expression is a function call that returns an unconstrained
4294 -- type, rewrite the declaration as a renaming of the result of the
4295 -- call. The exceptions below are cases where the copy is expected,
4296 -- either by the back end (Aliased case) or by the semantics, as for
4297 -- initializing controlled types or copying tags for classwide types.
4300 and then Nkind (E) = N_Explicit_Dereference
4301 and then Nkind (Original_Node (E)) = N_Function_Call
4302 and then not Is_Library_Level_Entity (Id)
4303 and then not Is_Constrained (Underlying_Type (T))
4304 and then not Is_Aliased (Id)
4305 and then not Is_Class_Wide_Type (T)
4306 and then not Is_Controlled_Active (T)
4307 and then not Has_Controlled_Component (Base_Type (T))
4308 and then Expander_Active
4311 Make_Object_Renaming_Declaration (Loc,
4312 Defining_Identifier => Id,
4313 Access_Definition => Empty,
4314 Subtype_Mark => New_Occurrence_Of
4315 (Base_Type (Etype (Id)), Loc),
4318 Set_Renamed_Object (Id, E);
4320 -- Force generation of debugging information for the constant and for
4321 -- the renamed function call.
4323 Set_Debug_Info_Needed (Id);
4324 Set_Debug_Info_Needed (Entity (Prefix (E)));
4327 if Present (Prev_Entity)
4328 and then Is_Frozen (Prev_Entity)
4329 and then not Error_Posted (Id)
4331 Error_Msg_N ("full constant declaration appears too late", N);
4334 Check_Eliminated (Id);
4336 -- Deal with setting In_Private_Part flag if in private part
4338 if Ekind (Scope (Id)) = E_Package
4339 and then In_Private_Part (Scope (Id))
4341 Set_In_Private_Part (Id);
4344 -- Check for violation of No_Local_Timing_Events
4346 if Restriction_Check_Required (No_Local_Timing_Events)
4347 and then not Is_Library_Level_Entity (Id)
4348 and then Is_RTE (Etype (Id), RE_Timing_Event)
4350 Check_Restriction (No_Local_Timing_Events, N);
4354 -- Initialize the refined state of a variable here because this is a
4355 -- common destination for legal and illegal object declarations.
4357 if Ekind (Id) = E_Variable then
4358 Set_Encapsulating_State (Id, Empty);
4361 if Has_Aspects (N) then
4362 Analyze_Aspect_Specifications (N, Id);
4365 Analyze_Dimension (N);
4367 -- Verify whether the object declaration introduces an illegal hidden
4368 -- state within a package subject to a null abstract state.
4370 if Ekind (Id) = E_Variable then
4371 Check_No_Hidden_State (Id);
4374 Ghost_Mode := Save_Ghost_Mode;
4375 end Analyze_Object_Declaration;
4377 ---------------------------
4378 -- Analyze_Others_Choice --
4379 ---------------------------
4381 -- Nothing to do for the others choice node itself, the semantic analysis
4382 -- of the others choice will occur as part of the processing of the parent
4384 procedure Analyze_Others_Choice (N : Node_Id) is
4385 pragma Warnings (Off, N);
4388 end Analyze_Others_Choice;
4390 -------------------------------------------
4391 -- Analyze_Private_Extension_Declaration --
4392 -------------------------------------------
4394 procedure Analyze_Private_Extension_Declaration (N : Node_Id) is
4395 Indic : constant Node_Id := Subtype_Indication (N);
4396 T : constant Entity_Id := Defining_Identifier (N);
4397 Parent_Base : Entity_Id;
4398 Parent_Type : Entity_Id;
4401 -- Ada 2005 (AI-251): Decorate all names in list of ancestor interfaces
4403 if Is_Non_Empty_List (Interface_List (N)) then
4409 Intf := First (Interface_List (N));
4410 while Present (Intf) loop
4411 T := Find_Type_Of_Subtype_Indic (Intf);
4413 Diagnose_Interface (Intf, T);
4419 Generate_Definition (T);
4421 -- For other than Ada 2012, just enter the name in the current scope
4423 if Ada_Version < Ada_2012 then
4426 -- Ada 2012 (AI05-0162): Enter the name in the current scope handling
4427 -- case of private type that completes an incomplete type.
4434 Prev := Find_Type_Name (N);
4436 pragma Assert (Prev = T
4437 or else (Ekind (Prev) = E_Incomplete_Type
4438 and then Present (Full_View (Prev))
4439 and then Full_View (Prev) = T));
4443 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
4444 Parent_Base := Base_Type (Parent_Type);
4446 if Parent_Type = Any_Type or else Etype (Parent_Type) = Any_Type then
4447 Set_Ekind (T, Ekind (Parent_Type));
4448 Set_Etype (T, Any_Type);
4451 elsif not Is_Tagged_Type (Parent_Type) then
4453 ("parent of type extension must be a tagged type ", Indic);
4456 elsif Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
4457 Error_Msg_N ("premature derivation of incomplete type", Indic);
4460 elsif Is_Concurrent_Type (Parent_Type) then
4462 ("parent type of a private extension cannot be "
4463 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
4465 Set_Etype (T, Any_Type);
4466 Set_Ekind (T, E_Limited_Private_Type);
4467 Set_Private_Dependents (T, New_Elmt_List);
4468 Set_Error_Posted (T);
4472 -- Perhaps the parent type should be changed to the class-wide type's
4473 -- specific type in this case to prevent cascading errors ???
4475 if Is_Class_Wide_Type (Parent_Type) then
4477 ("parent of type extension must not be a class-wide type", Indic);
4481 if (not Is_Package_Or_Generic_Package (Current_Scope)
4482 and then Nkind (Parent (N)) /= N_Generic_Subprogram_Declaration)
4483 or else In_Private_Part (Current_Scope)
4486 Error_Msg_N ("invalid context for private extension", N);
4489 -- Set common attributes
4491 Set_Is_Pure (T, Is_Pure (Current_Scope));
4492 Set_Scope (T, Current_Scope);
4493 Set_Ekind (T, E_Record_Type_With_Private);
4494 Init_Size_Align (T);
4495 Set_Default_SSO (T);
4497 Set_Etype (T, Parent_Base);
4498 Set_Has_Task (T, Has_Task (Parent_Base));
4499 Set_Has_Protected (T, Has_Task (Parent_Base));
4501 Set_Convention (T, Convention (Parent_Type));
4502 Set_First_Rep_Item (T, First_Rep_Item (Parent_Type));
4503 Set_Is_First_Subtype (T);
4504 Make_Class_Wide_Type (T);
4506 if Unknown_Discriminants_Present (N) then
4507 Set_Discriminant_Constraint (T, No_Elist);
4510 Build_Derived_Record_Type (N, Parent_Type, T);
4512 -- Propagate inherited invariant information. The new type has
4513 -- invariants, if the parent type has inheritable invariants,
4514 -- and these invariants can in turn be inherited.
4516 if Has_Inheritable_Invariants (Parent_Type) then
4517 Set_Has_Inheritable_Invariants (T);
4518 Set_Has_Invariants (T);
4521 -- Ada 2005 (AI-443): Synchronized private extension or a rewritten
4522 -- synchronized formal derived type.
4524 if Ada_Version >= Ada_2005 and then Synchronized_Present (N) then
4525 Set_Is_Limited_Record (T);
4527 -- Formal derived type case
4529 if Is_Generic_Type (T) then
4531 -- The parent must be a tagged limited type or a synchronized
4534 if (not Is_Tagged_Type (Parent_Type)
4535 or else not Is_Limited_Type (Parent_Type))
4537 (not Is_Interface (Parent_Type)
4538 or else not Is_Synchronized_Interface (Parent_Type))
4540 Error_Msg_NE ("parent type of & must be tagged limited " &
4541 "or synchronized", N, T);
4544 -- The progenitors (if any) must be limited or synchronized
4547 if Present (Interfaces (T)) then
4550 Iface_Elmt : Elmt_Id;
4553 Iface_Elmt := First_Elmt (Interfaces (T));
4554 while Present (Iface_Elmt) loop
4555 Iface := Node (Iface_Elmt);
4557 if not Is_Limited_Interface (Iface)
4558 and then not Is_Synchronized_Interface (Iface)
4560 Error_Msg_NE ("progenitor & must be limited " &
4561 "or synchronized", N, Iface);
4564 Next_Elmt (Iface_Elmt);
4569 -- Regular derived extension, the parent must be a limited or
4570 -- synchronized interface.
4573 if not Is_Interface (Parent_Type)
4574 or else (not Is_Limited_Interface (Parent_Type)
4575 and then not Is_Synchronized_Interface (Parent_Type))
4578 ("parent type of & must be limited interface", N, T);
4582 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
4583 -- extension with a synchronized parent must be explicitly declared
4584 -- synchronized, because the full view will be a synchronized type.
4585 -- This must be checked before the check for limited types below,
4586 -- to ensure that types declared limited are not allowed to extend
4587 -- synchronized interfaces.
4589 elsif Is_Interface (Parent_Type)
4590 and then Is_Synchronized_Interface (Parent_Type)
4591 and then not Synchronized_Present (N)
4594 ("private extension of& must be explicitly synchronized",
4597 elsif Limited_Present (N) then
4598 Set_Is_Limited_Record (T);
4600 if not Is_Limited_Type (Parent_Type)
4602 (not Is_Interface (Parent_Type)
4603 or else not Is_Limited_Interface (Parent_Type))
4605 Error_Msg_NE ("parent type& of limited extension must be limited",
4611 if Has_Aspects (N) then
4612 Analyze_Aspect_Specifications (N, T);
4614 end Analyze_Private_Extension_Declaration;
4616 ---------------------------------
4617 -- Analyze_Subtype_Declaration --
4618 ---------------------------------
4620 procedure Analyze_Subtype_Declaration
4622 Skip : Boolean := False)
4624 Id : constant Entity_Id := Defining_Identifier (N);
4625 R_Checks : Check_Result;
4629 Generate_Definition (Id);
4630 Set_Is_Pure (Id, Is_Pure (Current_Scope));
4631 Init_Size_Align (Id);
4633 -- The following guard condition on Enter_Name is to handle cases where
4634 -- the defining identifier has already been entered into the scope but
4635 -- the declaration as a whole needs to be analyzed.
4637 -- This case in particular happens for derived enumeration types. The
4638 -- derived enumeration type is processed as an inserted enumeration type
4639 -- declaration followed by a rewritten subtype declaration. The defining
4640 -- identifier, however, is entered into the name scope very early in the
4641 -- processing of the original type declaration and therefore needs to be
4642 -- avoided here, when the created subtype declaration is analyzed. (See
4643 -- Build_Derived_Types)
4645 -- This also happens when the full view of a private type is derived
4646 -- type with constraints. In this case the entity has been introduced
4647 -- in the private declaration.
4649 -- Finally this happens in some complex cases when validity checks are
4650 -- enabled, where the same subtype declaration may be analyzed twice.
4651 -- This can happen if the subtype is created by the pre-analysis of
4652 -- an attribute tht gives the range of a loop statement, and the loop
4653 -- itself appears within an if_statement that will be rewritten during
4657 or else (Present (Etype (Id))
4658 and then (Is_Private_Type (Etype (Id))
4659 or else Is_Task_Type (Etype (Id))
4660 or else Is_Rewrite_Substitution (N)))
4664 elsif Current_Entity (Id) = Id then
4671 T := Process_Subtype (Subtype_Indication (N), N, Id, 'P');
4673 -- Class-wide equivalent types of records with unknown discriminants
4674 -- involve the generation of an itype which serves as the private view
4675 -- of a constrained record subtype. In such cases the base type of the
4676 -- current subtype we are processing is the private itype. Use the full
4677 -- of the private itype when decorating various attributes.
4680 and then Is_Private_Type (T)
4681 and then Present (Full_View (T))
4686 -- Inherit common attributes
4688 Set_Is_Volatile (Id, Is_Volatile (T));
4689 Set_Treat_As_Volatile (Id, Treat_As_Volatile (T));
4690 Set_Is_Generic_Type (Id, Is_Generic_Type (Base_Type (T)));
4691 Set_Convention (Id, Convention (T));
4693 -- If ancestor has predicates then so does the subtype, and in addition
4694 -- we must delay the freeze to properly arrange predicate inheritance.
4696 -- The Ancestor_Type test is really unpleasant, there seem to be cases
4697 -- in which T = ID, so the above tests and assignments do nothing???
4699 if Has_Predicates (T)
4700 or else (Present (Ancestor_Subtype (T))
4701 and then Has_Predicates (Ancestor_Subtype (T)))
4703 Set_Has_Predicates (Id);
4704 Set_Has_Delayed_Freeze (Id);
4707 -- Subtype of Boolean cannot have a constraint in SPARK
4709 if Is_Boolean_Type (T)
4710 and then Nkind (Subtype_Indication (N)) = N_Subtype_Indication
4712 Check_SPARK_05_Restriction
4713 ("subtype of Boolean cannot have constraint", N);
4716 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4718 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
4724 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint then
4725 One_Cstr := First (Constraints (Cstr));
4726 while Present (One_Cstr) loop
4728 -- Index or discriminant constraint in SPARK must be a
4732 Nkind_In (One_Cstr, N_Identifier, N_Expanded_Name)
4734 Check_SPARK_05_Restriction
4735 ("subtype mark required", One_Cstr);
4737 -- String subtype must have a lower bound of 1 in SPARK.
4738 -- Note that we do not need to test for the non-static case
4739 -- here, since that was already taken care of in
4740 -- Process_Range_Expr_In_Decl.
4742 elsif Base_Type (T) = Standard_String then
4743 Get_Index_Bounds (One_Cstr, Low, High);
4745 if Is_OK_Static_Expression (Low)
4746 and then Expr_Value (Low) /= 1
4748 Check_SPARK_05_Restriction
4749 ("String subtype must have lower bound of 1", N);
4759 -- In the case where there is no constraint given in the subtype
4760 -- indication, Process_Subtype just returns the Subtype_Mark, so its
4761 -- semantic attributes must be established here.
4763 if Nkind (Subtype_Indication (N)) /= N_Subtype_Indication then
4764 Set_Etype (Id, Base_Type (T));
4766 -- Subtype of unconstrained array without constraint is not allowed
4769 if Is_Array_Type (T) and then not Is_Constrained (T) then
4770 Check_SPARK_05_Restriction
4771 ("subtype of unconstrained array must have constraint", N);
4776 Set_Ekind (Id, E_Array_Subtype);
4777 Copy_Array_Subtype_Attributes (Id, T);
4779 when Decimal_Fixed_Point_Kind =>
4780 Set_Ekind (Id, E_Decimal_Fixed_Point_Subtype);
4781 Set_Digits_Value (Id, Digits_Value (T));
4782 Set_Delta_Value (Id, Delta_Value (T));
4783 Set_Scale_Value (Id, Scale_Value (T));
4784 Set_Small_Value (Id, Small_Value (T));
4785 Set_Scalar_Range (Id, Scalar_Range (T));
4786 Set_Machine_Radix_10 (Id, Machine_Radix_10 (T));
4787 Set_Is_Constrained (Id, Is_Constrained (T));
4788 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4789 Set_RM_Size (Id, RM_Size (T));
4791 when Enumeration_Kind =>
4792 Set_Ekind (Id, E_Enumeration_Subtype);
4793 Set_First_Literal (Id, First_Literal (Base_Type (T)));
4794 Set_Scalar_Range (Id, Scalar_Range (T));
4795 Set_Is_Character_Type (Id, Is_Character_Type (T));
4796 Set_Is_Constrained (Id, Is_Constrained (T));
4797 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4798 Set_RM_Size (Id, RM_Size (T));
4799 Inherit_Predicate_Flags (Id, T);
4801 when Ordinary_Fixed_Point_Kind =>
4802 Set_Ekind (Id, E_Ordinary_Fixed_Point_Subtype);
4803 Set_Scalar_Range (Id, Scalar_Range (T));
4804 Set_Small_Value (Id, Small_Value (T));
4805 Set_Delta_Value (Id, Delta_Value (T));
4806 Set_Is_Constrained (Id, Is_Constrained (T));
4807 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4808 Set_RM_Size (Id, RM_Size (T));
4811 Set_Ekind (Id, E_Floating_Point_Subtype);
4812 Set_Scalar_Range (Id, Scalar_Range (T));
4813 Set_Digits_Value (Id, Digits_Value (T));
4814 Set_Is_Constrained (Id, Is_Constrained (T));
4816 -- If the floating point type has dimensions, these will be
4817 -- inherited subsequently when Analyze_Dimensions is called.
4819 when Signed_Integer_Kind =>
4820 Set_Ekind (Id, E_Signed_Integer_Subtype);
4821 Set_Scalar_Range (Id, Scalar_Range (T));
4822 Set_Is_Constrained (Id, Is_Constrained (T));
4823 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4824 Set_RM_Size (Id, RM_Size (T));
4825 Inherit_Predicate_Flags (Id, T);
4827 when Modular_Integer_Kind =>
4828 Set_Ekind (Id, E_Modular_Integer_Subtype);
4829 Set_Scalar_Range (Id, Scalar_Range (T));
4830 Set_Is_Constrained (Id, Is_Constrained (T));
4831 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4832 Set_RM_Size (Id, RM_Size (T));
4833 Inherit_Predicate_Flags (Id, T);
4835 when Class_Wide_Kind =>
4836 Set_Ekind (Id, E_Class_Wide_Subtype);
4837 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4838 Set_Cloned_Subtype (Id, T);
4839 Set_Is_Tagged_Type (Id, True);
4840 Set_Has_Unknown_Discriminants
4842 Set_No_Tagged_Streams_Pragma
4843 (Id, No_Tagged_Streams_Pragma (T));
4845 if Ekind (T) = E_Class_Wide_Subtype then
4846 Set_Equivalent_Type (Id, Equivalent_Type (T));
4849 when E_Record_Type | E_Record_Subtype =>
4850 Set_Ekind (Id, E_Record_Subtype);
4852 if Ekind (T) = E_Record_Subtype
4853 and then Present (Cloned_Subtype (T))
4855 Set_Cloned_Subtype (Id, Cloned_Subtype (T));
4857 Set_Cloned_Subtype (Id, T);
4860 Set_First_Entity (Id, First_Entity (T));
4861 Set_Last_Entity (Id, Last_Entity (T));
4862 Set_Has_Discriminants (Id, Has_Discriminants (T));
4863 Set_Is_Constrained (Id, Is_Constrained (T));
4864 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4865 Set_Has_Implicit_Dereference
4866 (Id, Has_Implicit_Dereference (T));
4867 Set_Has_Unknown_Discriminants
4868 (Id, Has_Unknown_Discriminants (T));
4870 if Has_Discriminants (T) then
4871 Set_Discriminant_Constraint
4872 (Id, Discriminant_Constraint (T));
4873 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4875 elsif Has_Unknown_Discriminants (Id) then
4876 Set_Discriminant_Constraint (Id, No_Elist);
4879 if Is_Tagged_Type (T) then
4880 Set_Is_Tagged_Type (Id, True);
4881 Set_No_Tagged_Streams_Pragma
4882 (Id, No_Tagged_Streams_Pragma (T));
4883 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4884 Set_Direct_Primitive_Operations
4885 (Id, Direct_Primitive_Operations (T));
4886 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4888 if Is_Interface (T) then
4889 Set_Is_Interface (Id);
4890 Set_Is_Limited_Interface (Id, Is_Limited_Interface (T));
4894 when Private_Kind =>
4895 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4896 Set_Has_Discriminants (Id, Has_Discriminants (T));
4897 Set_Is_Constrained (Id, Is_Constrained (T));
4898 Set_First_Entity (Id, First_Entity (T));
4899 Set_Last_Entity (Id, Last_Entity (T));
4900 Set_Private_Dependents (Id, New_Elmt_List);
4901 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4902 Set_Has_Implicit_Dereference
4903 (Id, Has_Implicit_Dereference (T));
4904 Set_Has_Unknown_Discriminants
4905 (Id, Has_Unknown_Discriminants (T));
4906 Set_Known_To_Have_Preelab_Init
4907 (Id, Known_To_Have_Preelab_Init (T));
4909 if Is_Tagged_Type (T) then
4910 Set_Is_Tagged_Type (Id);
4911 Set_No_Tagged_Streams_Pragma (Id,
4912 No_Tagged_Streams_Pragma (T));
4913 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4914 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4915 Set_Direct_Primitive_Operations (Id,
4916 Direct_Primitive_Operations (T));
4919 -- In general the attributes of the subtype of a private type
4920 -- are the attributes of the partial view of parent. However,
4921 -- the full view may be a discriminated type, and the subtype
4922 -- must share the discriminant constraint to generate correct
4923 -- calls to initialization procedures.
4925 if Has_Discriminants (T) then
4926 Set_Discriminant_Constraint
4927 (Id, Discriminant_Constraint (T));
4928 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4930 elsif Present (Full_View (T))
4931 and then Has_Discriminants (Full_View (T))
4933 Set_Discriminant_Constraint
4934 (Id, Discriminant_Constraint (Full_View (T)));
4935 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4937 -- This would seem semantically correct, but apparently
4938 -- generates spurious errors about missing components ???
4940 -- Set_Has_Discriminants (Id);
4943 Prepare_Private_Subtype_Completion (Id, N);
4945 -- If this is the subtype of a constrained private type with
4946 -- discriminants that has got a full view and we also have
4947 -- built a completion just above, show that the completion
4948 -- is a clone of the full view to the back-end.
4950 if Has_Discriminants (T)
4951 and then not Has_Unknown_Discriminants (T)
4952 and then not Is_Empty_Elmt_List (Discriminant_Constraint (T))
4953 and then Present (Full_View (T))
4954 and then Present (Full_View (Id))
4956 Set_Cloned_Subtype (Full_View (Id), Full_View (T));
4960 Set_Ekind (Id, E_Access_Subtype);
4961 Set_Is_Constrained (Id, Is_Constrained (T));
4962 Set_Is_Access_Constant
4963 (Id, Is_Access_Constant (T));
4964 Set_Directly_Designated_Type
4965 (Id, Designated_Type (T));
4966 Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T));
4968 -- A Pure library_item must not contain the declaration of a
4969 -- named access type, except within a subprogram, generic
4970 -- subprogram, task unit, or protected unit, or if it has
4971 -- a specified Storage_Size of zero (RM05-10.2.1(15.4-15.5)).
4973 if Comes_From_Source (Id)
4974 and then In_Pure_Unit
4975 and then not In_Subprogram_Task_Protected_Unit
4976 and then not No_Pool_Assigned (Id)
4979 ("named access types not allowed in pure unit", N);
4982 when Concurrent_Kind =>
4983 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4984 Set_Corresponding_Record_Type (Id,
4985 Corresponding_Record_Type (T));
4986 Set_First_Entity (Id, First_Entity (T));
4987 Set_First_Private_Entity (Id, First_Private_Entity (T));
4988 Set_Has_Discriminants (Id, Has_Discriminants (T));
4989 Set_Is_Constrained (Id, Is_Constrained (T));
4990 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
4991 Set_Last_Entity (Id, Last_Entity (T));
4993 if Is_Tagged_Type (T) then
4994 Set_No_Tagged_Streams_Pragma
4995 (Id, No_Tagged_Streams_Pragma (T));
4998 if Has_Discriminants (T) then
4999 Set_Discriminant_Constraint
5000 (Id, Discriminant_Constraint (T));
5001 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5004 when Incomplete_Kind =>
5005 if Ada_Version >= Ada_2005 then
5007 -- In Ada 2005 an incomplete type can be explicitly tagged:
5008 -- propagate indication. Note that we also have to include
5009 -- subtypes for Ada 2012 extended use of incomplete types.
5011 Set_Ekind (Id, E_Incomplete_Subtype);
5012 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
5013 Set_Private_Dependents (Id, New_Elmt_List);
5015 if Is_Tagged_Type (Id) then
5016 Set_No_Tagged_Streams_Pragma
5017 (Id, No_Tagged_Streams_Pragma (T));
5018 Set_Direct_Primitive_Operations (Id, New_Elmt_List);
5021 -- Ada 2005 (AI-412): Decorate an incomplete subtype of an
5022 -- incomplete type visible through a limited with clause.
5024 if From_Limited_With (T)
5025 and then Present (Non_Limited_View (T))
5027 Set_From_Limited_With (Id);
5028 Set_Non_Limited_View (Id, Non_Limited_View (T));
5030 -- Ada 2005 (AI-412): Add the regular incomplete subtype
5031 -- to the private dependents of the original incomplete
5032 -- type for future transformation.
5035 Append_Elmt (Id, Private_Dependents (T));
5038 -- If the subtype name denotes an incomplete type an error
5039 -- was already reported by Process_Subtype.
5042 Set_Etype (Id, Any_Type);
5046 raise Program_Error;
5050 if Etype (Id) = Any_Type then
5054 -- Some common processing on all types
5056 Set_Size_Info (Id, T);
5057 Set_First_Rep_Item (Id, First_Rep_Item (T));
5059 -- If the parent type is a generic actual, so is the subtype. This may
5060 -- happen in a nested instance. Why Comes_From_Source test???
5062 if not Comes_From_Source (N) then
5063 Set_Is_Generic_Actual_Type (Id, Is_Generic_Actual_Type (T));
5066 -- If this is a subtype declaration for an actual in an instance,
5067 -- inherit static and dynamic predicates if any.
5070 and then not Comes_From_Source (N)
5071 and then Has_Predicates (T)
5072 and then Present (Predicate_Function (T))
5074 Set_Subprograms_For_Type (Id, Subprograms_For_Type (T));
5076 if Has_Static_Predicate (T) then
5077 Set_Static_Discrete_Predicate (Id,
5078 Static_Discrete_Predicate (T));
5082 -- Remaining processing depends on characteristics of base type
5086 Set_Is_Immediately_Visible (Id, True);
5087 Set_Depends_On_Private (Id, Has_Private_Component (T));
5088 Set_Is_Descendant_Of_Address (Id, Is_Descendant_Of_Address (T));
5090 if Is_Interface (T) then
5091 Set_Is_Interface (Id);
5094 if Present (Generic_Parent_Type (N))
5096 (Nkind (Parent (Generic_Parent_Type (N))) /=
5097 N_Formal_Type_Declaration
5098 or else Nkind (Formal_Type_Definition
5099 (Parent (Generic_Parent_Type (N)))) /=
5100 N_Formal_Private_Type_Definition)
5102 if Is_Tagged_Type (Id) then
5104 -- If this is a generic actual subtype for a synchronized type,
5105 -- the primitive operations are those of the corresponding record
5106 -- for which there is a separate subtype declaration.
5108 if Is_Concurrent_Type (Id) then
5110 elsif Is_Class_Wide_Type (Id) then
5111 Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T));
5113 Derive_Subprograms (Generic_Parent_Type (N), Id, T);
5116 elsif Scope (Etype (Id)) /= Standard_Standard then
5117 Derive_Subprograms (Generic_Parent_Type (N), Id);
5121 if Is_Private_Type (T) and then Present (Full_View (T)) then
5122 Conditional_Delay (Id, Full_View (T));
5124 -- The subtypes of components or subcomponents of protected types
5125 -- do not need freeze nodes, which would otherwise appear in the
5126 -- wrong scope (before the freeze node for the protected type). The
5127 -- proper subtypes are those of the subcomponents of the corresponding
5130 elsif Ekind (Scope (Id)) /= E_Protected_Type
5131 and then Present (Scope (Scope (Id))) -- error defense
5132 and then Ekind (Scope (Scope (Id))) /= E_Protected_Type
5134 Conditional_Delay (Id, T);
5137 -- Check that Constraint_Error is raised for a scalar subtype indication
5138 -- when the lower or upper bound of a non-null range lies outside the
5139 -- range of the type mark.
5141 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5142 if Is_Scalar_Type (Etype (Id))
5143 and then Scalar_Range (Id) /=
5144 Scalar_Range (Etype (Subtype_Mark
5145 (Subtype_Indication (N))))
5149 Etype (Subtype_Mark (Subtype_Indication (N))));
5151 -- In the array case, check compatibility for each index
5153 elsif Is_Array_Type (Etype (Id)) and then Present (First_Index (Id))
5155 -- This really should be a subprogram that finds the indications
5159 Subt_Index : Node_Id := First_Index (Id);
5160 Target_Index : Node_Id :=
5162 (Subtype_Mark (Subtype_Indication (N))));
5163 Has_Dyn_Chk : Boolean := Has_Dynamic_Range_Check (N);
5166 while Present (Subt_Index) loop
5167 if ((Nkind (Subt_Index) = N_Identifier
5168 and then Ekind (Entity (Subt_Index)) in Scalar_Kind)
5169 or else Nkind (Subt_Index) = N_Subtype_Indication)
5171 Nkind (Scalar_Range (Etype (Subt_Index))) = N_Range
5174 Target_Typ : constant Entity_Id :=
5175 Etype (Target_Index);
5179 (Scalar_Range (Etype (Subt_Index)),
5182 Defining_Identifier (N));
5184 -- Reset Has_Dynamic_Range_Check on the subtype to
5185 -- prevent elision of the index check due to a dynamic
5186 -- check generated for a preceding index (needed since
5187 -- Insert_Range_Checks tries to avoid generating
5188 -- redundant checks on a given declaration).
5190 Set_Has_Dynamic_Range_Check (N, False);
5196 Sloc (Defining_Identifier (N)));
5198 -- Record whether this index involved a dynamic check
5201 Has_Dyn_Chk or else Has_Dynamic_Range_Check (N);
5205 Next_Index (Subt_Index);
5206 Next_Index (Target_Index);
5209 -- Finally, mark whether the subtype involves dynamic checks
5211 Set_Has_Dynamic_Range_Check (N, Has_Dyn_Chk);
5216 -- A type invariant applies to any subtype in its scope, in particular
5217 -- to a generic actual.
5219 if Has_Invariants (T) and then In_Open_Scopes (Scope (T)) then
5220 Set_Has_Invariants (Id);
5221 Set_Invariant_Procedure (Id, Invariant_Procedure (T));
5224 -- Make sure that generic actual types are properly frozen. The subtype
5225 -- is marked as a generic actual type when the enclosing instance is
5226 -- analyzed, so here we identify the subtype from the tree structure.
5229 and then Is_Generic_Actual_Type (Id)
5230 and then In_Instance
5231 and then not Comes_From_Source (N)
5232 and then Nkind (Subtype_Indication (N)) /= N_Subtype_Indication
5233 and then Is_Frozen (T)
5235 Freeze_Before (N, Id);
5238 Set_Optimize_Alignment_Flags (Id);
5239 Check_Eliminated (Id);
5242 if Has_Aspects (N) then
5243 Analyze_Aspect_Specifications (N, Id);
5246 Analyze_Dimension (N);
5248 -- Check No_Dynamic_Sized_Objects restriction, which disallows subtype
5249 -- indications on composite types where the constraints are dynamic.
5250 -- Note that object declarations and aggregates generate implicit
5251 -- subtype declarations, which this covers. One special case is that the
5252 -- implicitly generated "=" for discriminated types includes an
5253 -- offending subtype declaration, which is harmless, so we ignore it
5256 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5258 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
5260 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint
5261 and then not (Is_Internal (Id)
5262 and then Is_TSS (Scope (Id),
5263 TSS_Composite_Equality))
5264 and then not Within_Init_Proc
5265 and then not All_Composite_Constraints_Static (Cstr)
5267 Check_Restriction (No_Dynamic_Sized_Objects, Cstr);
5271 end Analyze_Subtype_Declaration;
5273 --------------------------------
5274 -- Analyze_Subtype_Indication --
5275 --------------------------------
5277 procedure Analyze_Subtype_Indication (N : Node_Id) is
5278 T : constant Entity_Id := Subtype_Mark (N);
5279 R : constant Node_Id := Range_Expression (Constraint (N));
5286 Set_Etype (N, Etype (R));
5287 Resolve (R, Entity (T));
5289 Set_Error_Posted (R);
5290 Set_Error_Posted (T);
5292 end Analyze_Subtype_Indication;
5294 --------------------------
5295 -- Analyze_Variant_Part --
5296 --------------------------
5298 procedure Analyze_Variant_Part (N : Node_Id) is
5299 Discr_Name : Node_Id;
5300 Discr_Type : Entity_Id;
5302 procedure Process_Variant (A : Node_Id);
5303 -- Analyze declarations for a single variant
5305 package Analyze_Variant_Choices is
5306 new Generic_Analyze_Choices (Process_Variant);
5307 use Analyze_Variant_Choices;
5309 ---------------------
5310 -- Process_Variant --
5311 ---------------------
5313 procedure Process_Variant (A : Node_Id) is
5314 CL : constant Node_Id := Component_List (A);
5316 if not Null_Present (CL) then
5317 Analyze_Declarations (Component_Items (CL));
5319 if Present (Variant_Part (CL)) then
5320 Analyze (Variant_Part (CL));
5323 end Process_Variant;
5325 -- Start of processing for Analyze_Variant_Part
5328 Discr_Name := Name (N);
5329 Analyze (Discr_Name);
5331 -- If Discr_Name bad, get out (prevent cascaded errors)
5333 if Etype (Discr_Name) = Any_Type then
5337 -- Check invalid discriminant in variant part
5339 if Ekind (Entity (Discr_Name)) /= E_Discriminant then
5340 Error_Msg_N ("invalid discriminant name in variant part", Discr_Name);
5343 Discr_Type := Etype (Entity (Discr_Name));
5345 if not Is_Discrete_Type (Discr_Type) then
5347 ("discriminant in a variant part must be of a discrete type",
5352 -- Now analyze the choices, which also analyzes the declarations that
5353 -- are associated with each choice.
5355 Analyze_Choices (Variants (N), Discr_Type);
5357 -- Note: we used to instantiate and call Check_Choices here to check
5358 -- that the choices covered the discriminant, but it's too early to do
5359 -- that because of statically predicated subtypes, whose analysis may
5360 -- be deferred to their freeze point which may be as late as the freeze
5361 -- point of the containing record. So this call is now to be found in
5362 -- Freeze_Record_Declaration.
5364 end Analyze_Variant_Part;
5366 ----------------------------
5367 -- Array_Type_Declaration --
5368 ----------------------------
5370 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is
5371 Component_Def : constant Node_Id := Component_Definition (Def);
5372 Component_Typ : constant Node_Id := Subtype_Indication (Component_Def);
5373 Element_Type : Entity_Id;
5374 Implicit_Base : Entity_Id;
5376 Related_Id : Entity_Id := Empty;
5378 P : constant Node_Id := Parent (Def);
5382 if Nkind (Def) = N_Constrained_Array_Definition then
5383 Index := First (Discrete_Subtype_Definitions (Def));
5385 Index := First (Subtype_Marks (Def));
5388 -- Find proper names for the implicit types which may be public. In case
5389 -- of anonymous arrays we use the name of the first object of that type
5393 Related_Id := Defining_Identifier (P);
5399 while Present (Index) loop
5402 -- Test for odd case of trying to index a type by the type itself
5404 if Is_Entity_Name (Index) and then Entity (Index) = T then
5405 Error_Msg_N ("type& cannot be indexed by itself", Index);
5406 Set_Entity (Index, Standard_Boolean);
5407 Set_Etype (Index, Standard_Boolean);
5410 -- Check SPARK restriction requiring a subtype mark
5412 if not Nkind_In (Index, N_Identifier, N_Expanded_Name) then
5413 Check_SPARK_05_Restriction ("subtype mark required", Index);
5416 -- Add a subtype declaration for each index of private array type
5417 -- declaration whose etype is also private. For example:
5420 -- type Index is private;
5422 -- type Table is array (Index) of ...
5425 -- This is currently required by the expander for the internally
5426 -- generated equality subprogram of records with variant parts in
5427 -- which the etype of some component is such private type.
5429 if Ekind (Current_Scope) = E_Package
5430 and then In_Private_Part (Current_Scope)
5431 and then Has_Private_Declaration (Etype (Index))
5434 Loc : constant Source_Ptr := Sloc (Def);
5439 New_E := Make_Temporary (Loc, 'T');
5440 Set_Is_Internal (New_E);
5443 Make_Subtype_Declaration (Loc,
5444 Defining_Identifier => New_E,
5445 Subtype_Indication =>
5446 New_Occurrence_Of (Etype (Index), Loc));
5448 Insert_Before (Parent (Def), Decl);
5450 Set_Etype (Index, New_E);
5452 -- If the index is a range the Entity attribute is not
5453 -- available. Example:
5456 -- type T is private;
5458 -- type T is new Natural;
5459 -- Table : array (T(1) .. T(10)) of Boolean;
5462 if Nkind (Index) /= N_Range then
5463 Set_Entity (Index, New_E);
5468 Make_Index (Index, P, Related_Id, Nb_Index);
5470 -- Check error of subtype with predicate for index type
5472 Bad_Predicated_Subtype_Use
5473 ("subtype& has predicate, not allowed as index subtype",
5474 Index, Etype (Index));
5476 -- Move to next index
5479 Nb_Index := Nb_Index + 1;
5482 -- Process subtype indication if one is present
5484 if Present (Component_Typ) then
5485 Element_Type := Process_Subtype (Component_Typ, P, Related_Id, 'C');
5487 Set_Etype (Component_Typ, Element_Type);
5489 if not Nkind_In (Component_Typ, N_Identifier, N_Expanded_Name) then
5490 Check_SPARK_05_Restriction
5491 ("subtype mark required", Component_Typ);
5494 -- Ada 2005 (AI-230): Access Definition case
5496 else pragma Assert (Present (Access_Definition (Component_Def)));
5498 -- Indicate that the anonymous access type is created by the
5499 -- array type declaration.
5501 Element_Type := Access_Definition
5503 N => Access_Definition (Component_Def));
5504 Set_Is_Local_Anonymous_Access (Element_Type);
5506 -- Propagate the parent. This field is needed if we have to generate
5507 -- the master_id associated with an anonymous access to task type
5508 -- component (see Expand_N_Full_Type_Declaration.Build_Master)
5510 Set_Parent (Element_Type, Parent (T));
5512 -- Ada 2005 (AI-230): In case of components that are anonymous access
5513 -- types the level of accessibility depends on the enclosing type
5516 Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230)
5518 -- Ada 2005 (AI-254)
5521 CD : constant Node_Id :=
5522 Access_To_Subprogram_Definition
5523 (Access_Definition (Component_Def));
5525 if Present (CD) and then Protected_Present (CD) then
5527 Replace_Anonymous_Access_To_Protected_Subprogram (Def);
5532 -- Constrained array case
5535 T := Create_Itype (E_Void, P, Related_Id, 'T');
5538 if Nkind (Def) = N_Constrained_Array_Definition then
5540 -- Establish Implicit_Base as unconstrained base type
5542 Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B');
5544 Set_Etype (Implicit_Base, Implicit_Base);
5545 Set_Scope (Implicit_Base, Current_Scope);
5546 Set_Has_Delayed_Freeze (Implicit_Base);
5547 Set_Default_SSO (Implicit_Base);
5549 -- The constrained array type is a subtype of the unconstrained one
5551 Set_Ekind (T, E_Array_Subtype);
5552 Init_Size_Align (T);
5553 Set_Etype (T, Implicit_Base);
5554 Set_Scope (T, Current_Scope);
5555 Set_Is_Constrained (T);
5557 First (Discrete_Subtype_Definitions (Def)));
5558 Set_Has_Delayed_Freeze (T);
5560 -- Complete setup of implicit base type
5562 Set_First_Index (Implicit_Base, First_Index (T));
5563 Set_Component_Type (Implicit_Base, Element_Type);
5564 Set_Has_Task (Implicit_Base, Has_Task (Element_Type));
5565 Set_Has_Protected (Implicit_Base, Has_Protected (Element_Type));
5566 Set_Component_Size (Implicit_Base, Uint_0);
5567 Set_Packed_Array_Impl_Type (Implicit_Base, Empty);
5568 Set_Has_Controlled_Component (Implicit_Base,
5569 Has_Controlled_Component (Element_Type)
5570 or else Is_Controlled_Active (Element_Type));
5571 Set_Finalize_Storage_Only (Implicit_Base,
5572 Finalize_Storage_Only (Element_Type));
5574 -- Inherit the "ghostness" from the constrained array type
5576 if Ghost_Mode > None or else Is_Ghost_Entity (T) then
5577 Set_Is_Ghost_Entity (Implicit_Base);
5580 -- Unconstrained array case
5583 Set_Ekind (T, E_Array_Type);
5584 Init_Size_Align (T);
5586 Set_Scope (T, Current_Scope);
5587 Set_Component_Size (T, Uint_0);
5588 Set_Is_Constrained (T, False);
5589 Set_First_Index (T, First (Subtype_Marks (Def)));
5590 Set_Has_Delayed_Freeze (T, True);
5591 Set_Has_Task (T, Has_Task (Element_Type));
5592 Set_Has_Protected (T, Has_Protected (Element_Type));
5593 Set_Has_Controlled_Component (T, Has_Controlled_Component
5596 Is_Controlled_Active (Element_Type));
5597 Set_Finalize_Storage_Only (T, Finalize_Storage_Only
5599 Set_Default_SSO (T);
5602 -- Common attributes for both cases
5604 Set_Component_Type (Base_Type (T), Element_Type);
5605 Set_Packed_Array_Impl_Type (T, Empty);
5607 if Aliased_Present (Component_Definition (Def)) then
5608 Check_SPARK_05_Restriction
5609 ("aliased is not allowed", Component_Definition (Def));
5610 Set_Has_Aliased_Components (Etype (T));
5613 -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the
5614 -- array type to ensure that objects of this type are initialized.
5616 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (Element_Type) then
5617 Set_Can_Never_Be_Null (T);
5619 if Null_Exclusion_Present (Component_Definition (Def))
5621 -- No need to check itypes because in their case this check was
5622 -- done at their point of creation
5624 and then not Is_Itype (Element_Type)
5627 ("`NOT NULL` not allowed (null already excluded)",
5628 Subtype_Indication (Component_Definition (Def)));
5632 Priv := Private_Component (Element_Type);
5634 if Present (Priv) then
5636 -- Check for circular definitions
5638 if Priv = Any_Type then
5639 Set_Component_Type (Etype (T), Any_Type);
5641 -- There is a gap in the visibility of operations on the composite
5642 -- type only if the component type is defined in a different scope.
5644 elsif Scope (Priv) = Current_Scope then
5647 elsif Is_Limited_Type (Priv) then
5648 Set_Is_Limited_Composite (Etype (T));
5649 Set_Is_Limited_Composite (T);
5651 Set_Is_Private_Composite (Etype (T));
5652 Set_Is_Private_Composite (T);
5656 -- A syntax error in the declaration itself may lead to an empty index
5657 -- list, in which case do a minimal patch.
5659 if No (First_Index (T)) then
5660 Error_Msg_N ("missing index definition in array type declaration", T);
5663 Indexes : constant List_Id :=
5664 New_List (New_Occurrence_Of (Any_Id, Sloc (T)));
5666 Set_Discrete_Subtype_Definitions (Def, Indexes);
5667 Set_First_Index (T, First (Indexes));
5672 -- Create a concatenation operator for the new type. Internal array
5673 -- types created for packed entities do not need such, they are
5674 -- compatible with the user-defined type.
5676 if Number_Dimensions (T) = 1
5677 and then not Is_Packed_Array_Impl_Type (T)
5679 New_Concatenation_Op (T);
5682 -- In the case of an unconstrained array the parser has already verified
5683 -- that all the indexes are unconstrained but we still need to make sure
5684 -- that the element type is constrained.
5686 if not Is_Definite_Subtype (Element_Type) then
5688 ("unconstrained element type in array declaration",
5689 Subtype_Indication (Component_Def));
5691 elsif Is_Abstract_Type (Element_Type) then
5693 ("the type of a component cannot be abstract",
5694 Subtype_Indication (Component_Def));
5697 -- There may be an invariant declared for the component type, but
5698 -- the construction of the component invariant checking procedure
5699 -- takes place during expansion.
5700 end Array_Type_Declaration;
5702 ------------------------------------------------------
5703 -- Replace_Anonymous_Access_To_Protected_Subprogram --
5704 ------------------------------------------------------
5706 function Replace_Anonymous_Access_To_Protected_Subprogram
5707 (N : Node_Id) return Entity_Id
5709 Loc : constant Source_Ptr := Sloc (N);
5711 Curr_Scope : constant Scope_Stack_Entry :=
5712 Scope_Stack.Table (Scope_Stack.Last);
5714 Anon : constant Entity_Id := Make_Temporary (Loc, 'S');
5717 -- Access definition in declaration
5720 -- Object definition or formal definition with an access definition
5723 -- Declaration of anonymous access to subprogram type
5726 -- Original specification in access to subprogram
5731 Set_Is_Internal (Anon);
5734 when N_Component_Declaration |
5735 N_Unconstrained_Array_Definition |
5736 N_Constrained_Array_Definition =>
5737 Comp := Component_Definition (N);
5738 Acc := Access_Definition (Comp);
5740 when N_Discriminant_Specification =>
5741 Comp := Discriminant_Type (N);
5744 when N_Parameter_Specification =>
5745 Comp := Parameter_Type (N);
5748 when N_Access_Function_Definition =>
5749 Comp := Result_Definition (N);
5752 when N_Object_Declaration =>
5753 Comp := Object_Definition (N);
5756 when N_Function_Specification =>
5757 Comp := Result_Definition (N);
5761 raise Program_Error;
5764 Spec := Access_To_Subprogram_Definition (Acc);
5767 Make_Full_Type_Declaration (Loc,
5768 Defining_Identifier => Anon,
5769 Type_Definition => Copy_Separate_Tree (Spec));
5771 Mark_Rewrite_Insertion (Decl);
5773 -- In ASIS mode, analyze the profile on the original node, because
5774 -- the separate copy does not provide enough links to recover the
5775 -- original tree. Analysis is limited to type annotations, within
5776 -- a temporary scope that serves as an anonymous subprogram to collect
5777 -- otherwise useless temporaries and itypes.
5781 Typ : constant Entity_Id := Make_Temporary (Loc, 'S');
5784 if Nkind (Spec) = N_Access_Function_Definition then
5785 Set_Ekind (Typ, E_Function);
5787 Set_Ekind (Typ, E_Procedure);
5790 Set_Parent (Typ, N);
5791 Set_Scope (Typ, Current_Scope);
5794 -- Nothing to do if procedure is parameterless
5796 if Present (Parameter_Specifications (Spec)) then
5797 Process_Formals (Parameter_Specifications (Spec), Spec);
5800 if Nkind (Spec) = N_Access_Function_Definition then
5802 Def : constant Node_Id := Result_Definition (Spec);
5805 -- The result might itself be an anonymous access type, so
5808 if Nkind (Def) = N_Access_Definition then
5809 if Present (Access_To_Subprogram_Definition (Def)) then
5812 Replace_Anonymous_Access_To_Protected_Subprogram
5815 Find_Type (Subtype_Mark (Def));
5828 -- Insert the new declaration in the nearest enclosing scope. If the
5829 -- node is a body and N is its return type, the declaration belongs in
5830 -- the enclosing scope.
5834 if Nkind (P) = N_Subprogram_Body
5835 and then Nkind (N) = N_Function_Specification
5840 while Present (P) and then not Has_Declarations (P) loop
5844 pragma Assert (Present (P));
5846 if Nkind (P) = N_Package_Specification then
5847 Prepend (Decl, Visible_Declarations (P));
5849 Prepend (Decl, Declarations (P));
5852 -- Replace the anonymous type with an occurrence of the new declaration.
5853 -- In all cases the rewritten node does not have the null-exclusion
5854 -- attribute because (if present) it was already inherited by the
5855 -- anonymous entity (Anon). Thus, in case of components we do not
5856 -- inherit this attribute.
5858 if Nkind (N) = N_Parameter_Specification then
5859 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5860 Set_Etype (Defining_Identifier (N), Anon);
5861 Set_Null_Exclusion_Present (N, False);
5863 elsif Nkind (N) = N_Object_Declaration then
5864 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5865 Set_Etype (Defining_Identifier (N), Anon);
5867 elsif Nkind (N) = N_Access_Function_Definition then
5868 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5870 elsif Nkind (N) = N_Function_Specification then
5871 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5872 Set_Etype (Defining_Unit_Name (N), Anon);
5876 Make_Component_Definition (Loc,
5877 Subtype_Indication => New_Occurrence_Of (Anon, Loc)));
5880 Mark_Rewrite_Insertion (Comp);
5882 if Nkind_In (N, N_Object_Declaration, N_Access_Function_Definition)
5883 or else (Nkind (Parent (N)) = N_Full_Type_Declaration
5884 and then not Is_Type (Current_Scope))
5887 -- Declaration can be analyzed in the current scope.
5892 -- Temporarily remove the current scope (record or subprogram) from
5893 -- the stack to add the new declarations to the enclosing scope.
5894 -- The anonymous entity is an Itype with the proper attributes.
5896 Scope_Stack.Decrement_Last;
5898 Set_Is_Itype (Anon);
5899 Set_Associated_Node_For_Itype (Anon, N);
5900 Scope_Stack.Append (Curr_Scope);
5903 Set_Ekind (Anon, E_Anonymous_Access_Protected_Subprogram_Type);
5904 Set_Can_Use_Internal_Rep (Anon, not Always_Compatible_Rep_On_Target);
5906 end Replace_Anonymous_Access_To_Protected_Subprogram;
5908 -------------------------------
5909 -- Build_Derived_Access_Type --
5910 -------------------------------
5912 procedure Build_Derived_Access_Type
5914 Parent_Type : Entity_Id;
5915 Derived_Type : Entity_Id)
5917 S : constant Node_Id := Subtype_Indication (Type_Definition (N));
5919 Desig_Type : Entity_Id;
5921 Discr_Con_Elist : Elist_Id;
5922 Discr_Con_El : Elmt_Id;
5926 -- Set the designated type so it is available in case this is an access
5927 -- to a self-referential type, e.g. a standard list type with a next
5928 -- pointer. Will be reset after subtype is built.
5930 Set_Directly_Designated_Type
5931 (Derived_Type, Designated_Type (Parent_Type));
5933 Subt := Process_Subtype (S, N);
5935 if Nkind (S) /= N_Subtype_Indication
5936 and then Subt /= Base_Type (Subt)
5938 Set_Ekind (Derived_Type, E_Access_Subtype);
5941 if Ekind (Derived_Type) = E_Access_Subtype then
5943 Pbase : constant Entity_Id := Base_Type (Parent_Type);
5944 Ibase : constant Entity_Id :=
5945 Create_Itype (Ekind (Pbase), N, Derived_Type, 'B');
5946 Svg_Chars : constant Name_Id := Chars (Ibase);
5947 Svg_Next_E : constant Entity_Id := Next_Entity (Ibase);
5950 Copy_Node (Pbase, Ibase);
5952 Set_Chars (Ibase, Svg_Chars);
5953 Set_Next_Entity (Ibase, Svg_Next_E);
5954 Set_Sloc (Ibase, Sloc (Derived_Type));
5955 Set_Scope (Ibase, Scope (Derived_Type));
5956 Set_Freeze_Node (Ibase, Empty);
5957 Set_Is_Frozen (Ibase, False);
5958 Set_Comes_From_Source (Ibase, False);
5959 Set_Is_First_Subtype (Ibase, False);
5961 Set_Etype (Ibase, Pbase);
5962 Set_Etype (Derived_Type, Ibase);
5966 Set_Directly_Designated_Type
5967 (Derived_Type, Designated_Type (Subt));
5969 Set_Is_Constrained (Derived_Type, Is_Constrained (Subt));
5970 Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type));
5971 Set_Size_Info (Derived_Type, Parent_Type);
5972 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
5973 Set_Depends_On_Private (Derived_Type,
5974 Has_Private_Component (Derived_Type));
5975 Conditional_Delay (Derived_Type, Subt);
5977 -- Ada 2005 (AI-231): Set the null-exclusion attribute, and verify
5978 -- that it is not redundant.
5980 if Null_Exclusion_Present (Type_Definition (N)) then
5981 Set_Can_Never_Be_Null (Derived_Type);
5983 elsif Can_Never_Be_Null (Parent_Type) then
5984 Set_Can_Never_Be_Null (Derived_Type);
5987 -- Note: we do not copy the Storage_Size_Variable, since we always go to
5988 -- the root type for this information.
5990 -- Apply range checks to discriminants for derived record case
5991 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
5993 Desig_Type := Designated_Type (Derived_Type);
5995 if Is_Composite_Type (Desig_Type)
5996 and then (not Is_Array_Type (Desig_Type))
5997 and then Has_Discriminants (Desig_Type)
5998 and then Base_Type (Desig_Type) /= Desig_Type
6000 Discr_Con_Elist := Discriminant_Constraint (Desig_Type);
6001 Discr_Con_El := First_Elmt (Discr_Con_Elist);
6003 Discr := First_Discriminant (Base_Type (Desig_Type));
6004 while Present (Discr_Con_El) loop
6005 Apply_Range_Check (Node (Discr_Con_El), Etype (Discr));
6006 Next_Elmt (Discr_Con_El);
6007 Next_Discriminant (Discr);
6010 end Build_Derived_Access_Type;
6012 ------------------------------
6013 -- Build_Derived_Array_Type --
6014 ------------------------------
6016 procedure Build_Derived_Array_Type
6018 Parent_Type : Entity_Id;
6019 Derived_Type : Entity_Id)
6021 Loc : constant Source_Ptr := Sloc (N);
6022 Tdef : constant Node_Id := Type_Definition (N);
6023 Indic : constant Node_Id := Subtype_Indication (Tdef);
6024 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
6025 Implicit_Base : Entity_Id;
6026 New_Indic : Node_Id;
6028 procedure Make_Implicit_Base;
6029 -- If the parent subtype is constrained, the derived type is a subtype
6030 -- of an implicit base type derived from the parent base.
6032 ------------------------
6033 -- Make_Implicit_Base --
6034 ------------------------
6036 procedure Make_Implicit_Base is
6039 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
6041 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
6042 Set_Etype (Implicit_Base, Parent_Base);
6044 Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base);
6045 Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base);
6047 Set_Has_Delayed_Freeze (Implicit_Base, True);
6049 -- Inherit the "ghostness" from the parent base type
6051 if Ghost_Mode > None or else Is_Ghost_Entity (Parent_Base) then
6052 Set_Is_Ghost_Entity (Implicit_Base);
6054 end Make_Implicit_Base;
6056 -- Start of processing for Build_Derived_Array_Type
6059 if not Is_Constrained (Parent_Type) then
6060 if Nkind (Indic) /= N_Subtype_Indication then
6061 Set_Ekind (Derived_Type, E_Array_Type);
6063 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
6064 Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type);
6066 Set_Has_Delayed_Freeze (Derived_Type, True);
6070 Set_Etype (Derived_Type, Implicit_Base);
6073 Make_Subtype_Declaration (Loc,
6074 Defining_Identifier => Derived_Type,
6075 Subtype_Indication =>
6076 Make_Subtype_Indication (Loc,
6077 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6078 Constraint => Constraint (Indic)));
6080 Rewrite (N, New_Indic);
6085 if Nkind (Indic) /= N_Subtype_Indication then
6088 Set_Ekind (Derived_Type, Ekind (Parent_Type));
6089 Set_Etype (Derived_Type, Implicit_Base);
6090 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
6093 Error_Msg_N ("illegal constraint on constrained type", Indic);
6097 -- If parent type is not a derived type itself, and is declared in
6098 -- closed scope (e.g. a subprogram), then we must explicitly introduce
6099 -- the new type's concatenation operator since Derive_Subprograms
6100 -- will not inherit the parent's operator. If the parent type is
6101 -- unconstrained, the operator is of the unconstrained base type.
6103 if Number_Dimensions (Parent_Type) = 1
6104 and then not Is_Limited_Type (Parent_Type)
6105 and then not Is_Derived_Type (Parent_Type)
6106 and then not Is_Package_Or_Generic_Package
6107 (Scope (Base_Type (Parent_Type)))
6109 if not Is_Constrained (Parent_Type)
6110 and then Is_Constrained (Derived_Type)
6112 New_Concatenation_Op (Implicit_Base);
6114 New_Concatenation_Op (Derived_Type);
6117 end Build_Derived_Array_Type;
6119 -----------------------------------
6120 -- Build_Derived_Concurrent_Type --
6121 -----------------------------------
6123 procedure Build_Derived_Concurrent_Type
6125 Parent_Type : Entity_Id;
6126 Derived_Type : Entity_Id)
6128 Loc : constant Source_Ptr := Sloc (N);
6130 Corr_Record : constant Entity_Id := Make_Temporary (Loc, 'C');
6131 Corr_Decl : Node_Id;
6132 Corr_Decl_Needed : Boolean;
6133 -- If the derived type has fewer discriminants than its parent, the
6134 -- corresponding record is also a derived type, in order to account for
6135 -- the bound discriminants. We create a full type declaration for it in
6138 Constraint_Present : constant Boolean :=
6139 Nkind (Subtype_Indication (Type_Definition (N))) =
6140 N_Subtype_Indication;
6142 D_Constraint : Node_Id;
6143 New_Constraint : Elist_Id;
6144 Old_Disc : Entity_Id;
6145 New_Disc : Entity_Id;
6149 Set_Stored_Constraint (Derived_Type, No_Elist);
6150 Corr_Decl_Needed := False;
6153 if Present (Discriminant_Specifications (N))
6154 and then Constraint_Present
6156 Old_Disc := First_Discriminant (Parent_Type);
6157 New_Disc := First (Discriminant_Specifications (N));
6158 while Present (New_Disc) and then Present (Old_Disc) loop
6159 Next_Discriminant (Old_Disc);
6164 if Present (Old_Disc) and then Expander_Active then
6166 -- The new type has fewer discriminants, so we need to create a new
6167 -- corresponding record, which is derived from the corresponding
6168 -- record of the parent, and has a stored constraint that captures
6169 -- the values of the discriminant constraints. The corresponding
6170 -- record is needed only if expander is active and code generation is
6173 -- The type declaration for the derived corresponding record has the
6174 -- same discriminant part and constraints as the current declaration.
6175 -- Copy the unanalyzed tree to build declaration.
6177 Corr_Decl_Needed := True;
6178 New_N := Copy_Separate_Tree (N);
6181 Make_Full_Type_Declaration (Loc,
6182 Defining_Identifier => Corr_Record,
6183 Discriminant_Specifications =>
6184 Discriminant_Specifications (New_N),
6186 Make_Derived_Type_Definition (Loc,
6187 Subtype_Indication =>
6188 Make_Subtype_Indication (Loc,
6191 (Corresponding_Record_Type (Parent_Type), Loc),
6194 (Subtype_Indication (Type_Definition (New_N))))));
6197 -- Copy Storage_Size and Relative_Deadline variables if task case
6199 if Is_Task_Type (Parent_Type) then
6200 Set_Storage_Size_Variable (Derived_Type,
6201 Storage_Size_Variable (Parent_Type));
6202 Set_Relative_Deadline_Variable (Derived_Type,
6203 Relative_Deadline_Variable (Parent_Type));
6206 if Present (Discriminant_Specifications (N)) then
6207 Push_Scope (Derived_Type);
6208 Check_Or_Process_Discriminants (N, Derived_Type);
6210 if Constraint_Present then
6212 Expand_To_Stored_Constraint
6214 Build_Discriminant_Constraints
6216 Subtype_Indication (Type_Definition (N)), True));
6221 elsif Constraint_Present then
6223 -- Build constrained subtype, copying the constraint, and derive
6224 -- from it to create a derived constrained type.
6227 Loc : constant Source_Ptr := Sloc (N);
6228 Anon : constant Entity_Id :=
6229 Make_Defining_Identifier (Loc,
6230 Chars => New_External_Name (Chars (Derived_Type), 'T'));
6235 Make_Subtype_Declaration (Loc,
6236 Defining_Identifier => Anon,
6237 Subtype_Indication =>
6238 New_Copy_Tree (Subtype_Indication (Type_Definition (N))));
6239 Insert_Before (N, Decl);
6242 Rewrite (Subtype_Indication (Type_Definition (N)),
6243 New_Occurrence_Of (Anon, Loc));
6244 Set_Analyzed (Derived_Type, False);
6250 -- By default, operations and private data are inherited from parent.
6251 -- However, in the presence of bound discriminants, a new corresponding
6252 -- record will be created, see below.
6254 Set_Has_Discriminants
6255 (Derived_Type, Has_Discriminants (Parent_Type));
6256 Set_Corresponding_Record_Type
6257 (Derived_Type, Corresponding_Record_Type (Parent_Type));
6259 -- Is_Constrained is set according the parent subtype, but is set to
6260 -- False if the derived type is declared with new discriminants.
6264 (Is_Constrained (Parent_Type) or else Constraint_Present)
6265 and then not Present (Discriminant_Specifications (N)));
6267 if Constraint_Present then
6268 if not Has_Discriminants (Parent_Type) then
6269 Error_Msg_N ("untagged parent must have discriminants", N);
6271 elsif Present (Discriminant_Specifications (N)) then
6273 -- Verify that new discriminants are used to constrain old ones
6278 (Constraint (Subtype_Indication (Type_Definition (N)))));
6280 Old_Disc := First_Discriminant (Parent_Type);
6282 while Present (D_Constraint) loop
6283 if Nkind (D_Constraint) /= N_Discriminant_Association then
6285 -- Positional constraint. If it is a reference to a new
6286 -- discriminant, it constrains the corresponding old one.
6288 if Nkind (D_Constraint) = N_Identifier then
6289 New_Disc := First_Discriminant (Derived_Type);
6290 while Present (New_Disc) loop
6291 exit when Chars (New_Disc) = Chars (D_Constraint);
6292 Next_Discriminant (New_Disc);
6295 if Present (New_Disc) then
6296 Set_Corresponding_Discriminant (New_Disc, Old_Disc);
6300 Next_Discriminant (Old_Disc);
6302 -- if this is a named constraint, search by name for the old
6303 -- discriminants constrained by the new one.
6305 elsif Nkind (Expression (D_Constraint)) = N_Identifier then
6307 -- Find new discriminant with that name
6309 New_Disc := First_Discriminant (Derived_Type);
6310 while Present (New_Disc) loop
6312 Chars (New_Disc) = Chars (Expression (D_Constraint));
6313 Next_Discriminant (New_Disc);
6316 if Present (New_Disc) then
6318 -- Verify that new discriminant renames some discriminant
6319 -- of the parent type, and associate the new discriminant
6320 -- with one or more old ones that it renames.
6326 Selector := First (Selector_Names (D_Constraint));
6327 while Present (Selector) loop
6328 Old_Disc := First_Discriminant (Parent_Type);
6329 while Present (Old_Disc) loop
6330 exit when Chars (Old_Disc) = Chars (Selector);
6331 Next_Discriminant (Old_Disc);
6334 if Present (Old_Disc) then
6335 Set_Corresponding_Discriminant
6336 (New_Disc, Old_Disc);
6345 Next (D_Constraint);
6348 New_Disc := First_Discriminant (Derived_Type);
6349 while Present (New_Disc) loop
6350 if No (Corresponding_Discriminant (New_Disc)) then
6352 ("new discriminant& must constrain old one", N, New_Disc);
6355 Subtypes_Statically_Compatible
6357 Etype (Corresponding_Discriminant (New_Disc)))
6360 ("& not statically compatible with parent discriminant",
6364 Next_Discriminant (New_Disc);
6368 elsif Present (Discriminant_Specifications (N)) then
6370 ("missing discriminant constraint in untagged derivation", N);
6373 -- The entity chain of the derived type includes the new discriminants
6374 -- but shares operations with the parent.
6376 if Present (Discriminant_Specifications (N)) then
6377 Old_Disc := First_Discriminant (Parent_Type);
6378 while Present (Old_Disc) loop
6379 if No (Next_Entity (Old_Disc))
6380 or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant
6383 (Last_Entity (Derived_Type), Next_Entity (Old_Disc));
6387 Next_Discriminant (Old_Disc);
6391 Set_First_Entity (Derived_Type, First_Entity (Parent_Type));
6392 if Has_Discriminants (Parent_Type) then
6393 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6394 Set_Discriminant_Constraint (
6395 Derived_Type, Discriminant_Constraint (Parent_Type));
6399 Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type));
6401 Set_Has_Completion (Derived_Type);
6403 if Corr_Decl_Needed then
6404 Set_Stored_Constraint (Derived_Type, New_Constraint);
6405 Insert_After (N, Corr_Decl);
6406 Analyze (Corr_Decl);
6407 Set_Corresponding_Record_Type (Derived_Type, Corr_Record);
6409 end Build_Derived_Concurrent_Type;
6411 ------------------------------------
6412 -- Build_Derived_Enumeration_Type --
6413 ------------------------------------
6415 procedure Build_Derived_Enumeration_Type
6417 Parent_Type : Entity_Id;
6418 Derived_Type : Entity_Id)
6420 Loc : constant Source_Ptr := Sloc (N);
6421 Def : constant Node_Id := Type_Definition (N);
6422 Indic : constant Node_Id := Subtype_Indication (Def);
6423 Implicit_Base : Entity_Id;
6424 Literal : Entity_Id;
6425 New_Lit : Entity_Id;
6426 Literals_List : List_Id;
6427 Type_Decl : Node_Id;
6429 Rang_Expr : Node_Id;
6432 -- Since types Standard.Character and Standard.[Wide_]Wide_Character do
6433 -- not have explicit literals lists we need to process types derived
6434 -- from them specially. This is handled by Derived_Standard_Character.
6435 -- If the parent type is a generic type, there are no literals either,
6436 -- and we construct the same skeletal representation as for the generic
6439 if Is_Standard_Character_Type (Parent_Type) then
6440 Derived_Standard_Character (N, Parent_Type, Derived_Type);
6442 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
6448 if Nkind (Indic) /= N_Subtype_Indication then
6450 Make_Attribute_Reference (Loc,
6451 Attribute_Name => Name_First,
6452 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6453 Set_Etype (Lo, Derived_Type);
6456 Make_Attribute_Reference (Loc,
6457 Attribute_Name => Name_Last,
6458 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6459 Set_Etype (Hi, Derived_Type);
6461 Set_Scalar_Range (Derived_Type,
6467 -- Analyze subtype indication and verify compatibility
6468 -- with parent type.
6470 if Base_Type (Process_Subtype (Indic, N)) /=
6471 Base_Type (Parent_Type)
6474 ("illegal constraint for formal discrete type", N);
6480 -- If a constraint is present, analyze the bounds to catch
6481 -- premature usage of the derived literals.
6483 if Nkind (Indic) = N_Subtype_Indication
6484 and then Nkind (Range_Expression (Constraint (Indic))) = N_Range
6486 Analyze (Low_Bound (Range_Expression (Constraint (Indic))));
6487 Analyze (High_Bound (Range_Expression (Constraint (Indic))));
6490 -- Introduce an implicit base type for the derived type even if there
6491 -- is no constraint attached to it, since this seems closer to the
6492 -- Ada semantics. Build a full type declaration tree for the derived
6493 -- type using the implicit base type as the defining identifier. The
6494 -- build a subtype declaration tree which applies the constraint (if
6495 -- any) have it replace the derived type declaration.
6497 Literal := First_Literal (Parent_Type);
6498 Literals_List := New_List;
6499 while Present (Literal)
6500 and then Ekind (Literal) = E_Enumeration_Literal
6502 -- Literals of the derived type have the same representation as
6503 -- those of the parent type, but this representation can be
6504 -- overridden by an explicit representation clause. Indicate
6505 -- that there is no explicit representation given yet. These
6506 -- derived literals are implicit operations of the new type,
6507 -- and can be overridden by explicit ones.
6509 if Nkind (Literal) = N_Defining_Character_Literal then
6511 Make_Defining_Character_Literal (Loc, Chars (Literal));
6513 New_Lit := Make_Defining_Identifier (Loc, Chars (Literal));
6516 Set_Ekind (New_Lit, E_Enumeration_Literal);
6517 Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal));
6518 Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal));
6519 Set_Enumeration_Rep_Expr (New_Lit, Empty);
6520 Set_Alias (New_Lit, Literal);
6521 Set_Is_Known_Valid (New_Lit, True);
6523 Append (New_Lit, Literals_List);
6524 Next_Literal (Literal);
6528 Make_Defining_Identifier (Sloc (Derived_Type),
6529 Chars => New_External_Name (Chars (Derived_Type), 'B'));
6531 -- Indicate the proper nature of the derived type. This must be done
6532 -- before analysis of the literals, to recognize cases when a literal
6533 -- may be hidden by a previous explicit function definition (cf.
6536 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
6537 Set_Etype (Derived_Type, Implicit_Base);
6540 Make_Full_Type_Declaration (Loc,
6541 Defining_Identifier => Implicit_Base,
6542 Discriminant_Specifications => No_List,
6544 Make_Enumeration_Type_Definition (Loc, Literals_List));
6546 Mark_Rewrite_Insertion (Type_Decl);
6547 Insert_Before (N, Type_Decl);
6548 Analyze (Type_Decl);
6550 -- The anonymous base now has a full declaration, but this base
6551 -- is not a first subtype.
6553 Set_Is_First_Subtype (Implicit_Base, False);
6555 -- After the implicit base is analyzed its Etype needs to be changed
6556 -- to reflect the fact that it is derived from the parent type which
6557 -- was ignored during analysis. We also set the size at this point.
6559 Set_Etype (Implicit_Base, Parent_Type);
6561 Set_Size_Info (Implicit_Base, Parent_Type);
6562 Set_RM_Size (Implicit_Base, RM_Size (Parent_Type));
6563 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type));
6565 -- Copy other flags from parent type
6567 Set_Has_Non_Standard_Rep
6568 (Implicit_Base, Has_Non_Standard_Rep
6570 Set_Has_Pragma_Ordered
6571 (Implicit_Base, Has_Pragma_Ordered
6573 Set_Has_Delayed_Freeze (Implicit_Base);
6575 -- Process the subtype indication including a validation check on the
6576 -- constraint, if any. If a constraint is given, its bounds must be
6577 -- implicitly converted to the new type.
6579 if Nkind (Indic) = N_Subtype_Indication then
6581 R : constant Node_Id :=
6582 Range_Expression (Constraint (Indic));
6585 if Nkind (R) = N_Range then
6586 Hi := Build_Scalar_Bound
6587 (High_Bound (R), Parent_Type, Implicit_Base);
6588 Lo := Build_Scalar_Bound
6589 (Low_Bound (R), Parent_Type, Implicit_Base);
6592 -- Constraint is a Range attribute. Replace with explicit
6593 -- mention of the bounds of the prefix, which must be a
6596 Analyze (Prefix (R));
6598 Convert_To (Implicit_Base,
6599 Make_Attribute_Reference (Loc,
6600 Attribute_Name => Name_Last,
6602 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6605 Convert_To (Implicit_Base,
6606 Make_Attribute_Reference (Loc,
6607 Attribute_Name => Name_First,
6609 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6616 (Type_High_Bound (Parent_Type),
6617 Parent_Type, Implicit_Base);
6620 (Type_Low_Bound (Parent_Type),
6621 Parent_Type, Implicit_Base);
6629 -- If we constructed a default range for the case where no range
6630 -- was given, then the expressions in the range must not freeze
6631 -- since they do not correspond to expressions in the source.
6633 if Nkind (Indic) /= N_Subtype_Indication then
6634 Set_Must_Not_Freeze (Lo);
6635 Set_Must_Not_Freeze (Hi);
6636 Set_Must_Not_Freeze (Rang_Expr);
6640 Make_Subtype_Declaration (Loc,
6641 Defining_Identifier => Derived_Type,
6642 Subtype_Indication =>
6643 Make_Subtype_Indication (Loc,
6644 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6646 Make_Range_Constraint (Loc,
6647 Range_Expression => Rang_Expr))));
6651 -- Propagate the aspects from the original type declaration to the
6652 -- declaration of the implicit base.
6654 Move_Aspects (From => Original_Node (N), To => Type_Decl);
6656 -- Apply a range check. Since this range expression doesn't have an
6657 -- Etype, we have to specifically pass the Source_Typ parameter. Is
6660 if Nkind (Indic) = N_Subtype_Indication then
6662 (Range_Expression (Constraint (Indic)), Parent_Type,
6663 Source_Typ => Entity (Subtype_Mark (Indic)));
6666 end Build_Derived_Enumeration_Type;
6668 --------------------------------
6669 -- Build_Derived_Numeric_Type --
6670 --------------------------------
6672 procedure Build_Derived_Numeric_Type
6674 Parent_Type : Entity_Id;
6675 Derived_Type : Entity_Id)
6677 Loc : constant Source_Ptr := Sloc (N);
6678 Tdef : constant Node_Id := Type_Definition (N);
6679 Indic : constant Node_Id := Subtype_Indication (Tdef);
6680 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
6681 No_Constraint : constant Boolean := Nkind (Indic) /=
6682 N_Subtype_Indication;
6683 Implicit_Base : Entity_Id;
6689 -- Process the subtype indication including a validation check on
6690 -- the constraint if any.
6692 Discard_Node (Process_Subtype (Indic, N));
6694 -- Introduce an implicit base type for the derived type even if there
6695 -- is no constraint attached to it, since this seems closer to the Ada
6699 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
6701 Set_Etype (Implicit_Base, Parent_Base);
6702 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
6703 Set_Size_Info (Implicit_Base, Parent_Base);
6704 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base));
6705 Set_Parent (Implicit_Base, Parent (Derived_Type));
6706 Set_Is_Known_Valid (Implicit_Base, Is_Known_Valid (Parent_Base));
6708 -- Set RM Size for discrete type or decimal fixed-point type
6709 -- Ordinary fixed-point is excluded, why???
6711 if Is_Discrete_Type (Parent_Base)
6712 or else Is_Decimal_Fixed_Point_Type (Parent_Base)
6714 Set_RM_Size (Implicit_Base, RM_Size (Parent_Base));
6717 Set_Has_Delayed_Freeze (Implicit_Base);
6719 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
6720 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
6722 Set_Scalar_Range (Implicit_Base,
6727 if Has_Infinities (Parent_Base) then
6728 Set_Includes_Infinities (Scalar_Range (Implicit_Base));
6731 -- The Derived_Type, which is the entity of the declaration, is a
6732 -- subtype of the implicit base. Its Ekind is a subtype, even in the
6733 -- absence of an explicit constraint.
6735 Set_Etype (Derived_Type, Implicit_Base);
6737 -- If we did not have a constraint, then the Ekind is set from the
6738 -- parent type (otherwise Process_Subtype has set the bounds)
6740 if No_Constraint then
6741 Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type)));
6744 -- If we did not have a range constraint, then set the range from the
6745 -- parent type. Otherwise, the Process_Subtype call has set the bounds.
6747 if No_Constraint or else not Has_Range_Constraint (Indic) then
6748 Set_Scalar_Range (Derived_Type,
6750 Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)),
6751 High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type))));
6752 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6754 if Has_Infinities (Parent_Type) then
6755 Set_Includes_Infinities (Scalar_Range (Derived_Type));
6758 Set_Is_Known_Valid (Derived_Type, Is_Known_Valid (Parent_Type));
6761 Set_Is_Descendant_Of_Address (Derived_Type,
6762 Is_Descendant_Of_Address (Parent_Type));
6763 Set_Is_Descendant_Of_Address (Implicit_Base,
6764 Is_Descendant_Of_Address (Parent_Type));
6766 -- Set remaining type-specific fields, depending on numeric type
6768 if Is_Modular_Integer_Type (Parent_Type) then
6769 Set_Modulus (Implicit_Base, Modulus (Parent_Base));
6771 Set_Non_Binary_Modulus
6772 (Implicit_Base, Non_Binary_Modulus (Parent_Base));
6775 (Implicit_Base, Is_Known_Valid (Parent_Base));
6777 elsif Is_Floating_Point_Type (Parent_Type) then
6779 -- Digits of base type is always copied from the digits value of
6780 -- the parent base type, but the digits of the derived type will
6781 -- already have been set if there was a constraint present.
6783 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6784 Set_Float_Rep (Implicit_Base, Float_Rep (Parent_Base));
6786 if No_Constraint then
6787 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type));
6790 elsif Is_Fixed_Point_Type (Parent_Type) then
6792 -- Small of base type and derived type are always copied from the
6793 -- parent base type, since smalls never change. The delta of the
6794 -- base type is also copied from the parent base type. However the
6795 -- delta of the derived type will have been set already if a
6796 -- constraint was present.
6798 Set_Small_Value (Derived_Type, Small_Value (Parent_Base));
6799 Set_Small_Value (Implicit_Base, Small_Value (Parent_Base));
6800 Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base));
6802 if No_Constraint then
6803 Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type));
6806 -- The scale and machine radix in the decimal case are always
6807 -- copied from the parent base type.
6809 if Is_Decimal_Fixed_Point_Type (Parent_Type) then
6810 Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base));
6811 Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base));
6813 Set_Machine_Radix_10
6814 (Derived_Type, Machine_Radix_10 (Parent_Base));
6815 Set_Machine_Radix_10
6816 (Implicit_Base, Machine_Radix_10 (Parent_Base));
6818 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6820 if No_Constraint then
6821 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base));
6824 -- the analysis of the subtype_indication sets the
6825 -- digits value of the derived type.
6832 if Is_Integer_Type (Parent_Type) then
6833 Set_Has_Shift_Operator
6834 (Implicit_Base, Has_Shift_Operator (Parent_Type));
6837 -- The type of the bounds is that of the parent type, and they
6838 -- must be converted to the derived type.
6840 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
6842 -- The implicit_base should be frozen when the derived type is frozen,
6843 -- but note that it is used in the conversions of the bounds. For fixed
6844 -- types we delay the determination of the bounds until the proper
6845 -- freezing point. For other numeric types this is rejected by GCC, for
6846 -- reasons that are currently unclear (???), so we choose to freeze the
6847 -- implicit base now. In the case of integers and floating point types
6848 -- this is harmless because subsequent representation clauses cannot
6849 -- affect anything, but it is still baffling that we cannot use the
6850 -- same mechanism for all derived numeric types.
6852 -- There is a further complication: actually some representation
6853 -- clauses can affect the implicit base type. For example, attribute
6854 -- definition clauses for stream-oriented attributes need to set the
6855 -- corresponding TSS entries on the base type, and this normally
6856 -- cannot be done after the base type is frozen, so the circuitry in
6857 -- Sem_Ch13.New_Stream_Subprogram must account for this possibility
6858 -- and not use Set_TSS in this case.
6860 -- There are also consequences for the case of delayed representation
6861 -- aspects for some cases. For example, a Size aspect is delayed and
6862 -- should not be evaluated to the freeze point. This early freezing
6863 -- means that the size attribute evaluation happens too early???
6865 if Is_Fixed_Point_Type (Parent_Type) then
6866 Conditional_Delay (Implicit_Base, Parent_Type);
6868 Freeze_Before (N, Implicit_Base);
6870 end Build_Derived_Numeric_Type;
6872 --------------------------------
6873 -- Build_Derived_Private_Type --
6874 --------------------------------
6876 procedure Build_Derived_Private_Type
6878 Parent_Type : Entity_Id;
6879 Derived_Type : Entity_Id;
6880 Is_Completion : Boolean;
6881 Derive_Subps : Boolean := True)
6883 Loc : constant Source_Ptr := Sloc (N);
6884 Par_Base : constant Entity_Id := Base_Type (Parent_Type);
6885 Par_Scope : constant Entity_Id := Scope (Par_Base);
6886 Full_N : constant Node_Id := New_Copy_Tree (N);
6887 Full_Der : Entity_Id := New_Copy (Derived_Type);
6890 procedure Build_Full_Derivation;
6891 -- Build full derivation, i.e. derive from the full view
6893 procedure Copy_And_Build;
6894 -- Copy derived type declaration, replace parent with its full view,
6895 -- and build derivation
6897 ---------------------------
6898 -- Build_Full_Derivation --
6899 ---------------------------
6901 procedure Build_Full_Derivation is
6903 -- If parent scope is not open, install the declarations
6905 if not In_Open_Scopes (Par_Scope) then
6906 Install_Private_Declarations (Par_Scope);
6907 Install_Visible_Declarations (Par_Scope);
6909 Uninstall_Declarations (Par_Scope);
6911 -- If parent scope is open and in another unit, and parent has a
6912 -- completion, then the derivation is taking place in the visible
6913 -- part of a child unit. In that case retrieve the full view of
6914 -- the parent momentarily.
6916 elsif not In_Same_Source_Unit (N, Parent_Type) then
6917 Full_P := Full_View (Parent_Type);
6918 Exchange_Declarations (Parent_Type);
6920 Exchange_Declarations (Full_P);
6922 -- Otherwise it is a local derivation
6927 end Build_Full_Derivation;
6929 --------------------
6930 -- Copy_And_Build --
6931 --------------------
6933 procedure Copy_And_Build is
6934 Full_Parent : Entity_Id := Parent_Type;
6937 -- If the parent is itself derived from another private type,
6938 -- installing the private declarations has not affected its
6939 -- privacy status, so use its own full view explicitly.
6941 if Is_Private_Type (Full_Parent)
6942 and then Present (Full_View (Full_Parent))
6944 Full_Parent := Full_View (Full_Parent);
6947 -- And its underlying full view if necessary
6949 if Is_Private_Type (Full_Parent)
6950 and then Present (Underlying_Full_View (Full_Parent))
6952 Full_Parent := Underlying_Full_View (Full_Parent);
6955 -- For record, access and most enumeration types, derivation from
6956 -- the full view requires a fully-fledged declaration. In the other
6957 -- cases, just use an itype.
6959 if Ekind (Full_Parent) in Record_Kind
6960 or else Ekind (Full_Parent) in Access_Kind
6962 (Ekind (Full_Parent) in Enumeration_Kind
6963 and then not Is_Standard_Character_Type (Full_Parent)
6964 and then not Is_Generic_Type (Root_Type (Full_Parent)))
6966 -- Copy and adjust declaration to provide a completion for what
6967 -- is originally a private declaration. Indicate that full view
6968 -- is internally generated.
6970 Set_Comes_From_Source (Full_N, False);
6971 Set_Comes_From_Source (Full_Der, False);
6972 Set_Parent (Full_Der, Full_N);
6973 Set_Defining_Identifier (Full_N, Full_Der);
6975 -- If there are no constraints, adjust the subtype mark
6977 if Nkind (Subtype_Indication (Type_Definition (Full_N))) /=
6978 N_Subtype_Indication
6980 Set_Subtype_Indication
6981 (Type_Definition (Full_N),
6982 New_Occurrence_Of (Full_Parent, Sloc (Full_N)));
6985 Insert_After (N, Full_N);
6987 -- Build full view of derived type from full view of parent which
6988 -- is now installed. Subprograms have been derived on the partial
6989 -- view, the completion does not derive them anew.
6991 if Ekind (Full_Parent) in Record_Kind then
6993 -- If parent type is tagged, the completion inherits the proper
6994 -- primitive operations.
6996 if Is_Tagged_Type (Parent_Type) then
6997 Build_Derived_Record_Type
6998 (Full_N, Full_Parent, Full_Der, Derive_Subps);
7000 Build_Derived_Record_Type
7001 (Full_N, Full_Parent, Full_Der, Derive_Subps => False);
7006 (Full_N, Full_Parent, Full_Der,
7007 Is_Completion => False, Derive_Subps => False);
7010 -- The full declaration has been introduced into the tree and
7011 -- processed in the step above. It should not be analyzed again
7012 -- (when encountered later in the current list of declarations)
7013 -- to prevent spurious name conflicts. The full entity remains
7016 Set_Analyzed (Full_N);
7020 Make_Defining_Identifier (Sloc (Derived_Type),
7021 Chars => Chars (Derived_Type));
7022 Set_Is_Itype (Full_Der);
7023 Set_Associated_Node_For_Itype (Full_Der, N);
7024 Set_Parent (Full_Der, N);
7026 (N, Full_Parent, Full_Der,
7027 Is_Completion => False, Derive_Subps => False);
7030 Set_Has_Private_Declaration (Full_Der);
7031 Set_Has_Private_Declaration (Derived_Type);
7033 Set_Scope (Full_Der, Scope (Derived_Type));
7034 Set_Is_First_Subtype (Full_Der, Is_First_Subtype (Derived_Type));
7035 Set_Has_Size_Clause (Full_Der, False);
7036 Set_Has_Alignment_Clause (Full_Der, False);
7037 Set_Has_Delayed_Freeze (Full_Der);
7038 Set_Is_Frozen (Full_Der, False);
7039 Set_Freeze_Node (Full_Der, Empty);
7040 Set_Depends_On_Private (Full_Der, Has_Private_Component (Full_Der));
7041 Set_Is_Public (Full_Der, Is_Public (Derived_Type));
7043 -- The convention on the base type may be set in the private part
7044 -- and not propagated to the subtype until later, so we obtain the
7045 -- convention from the base type of the parent.
7047 Set_Convention (Full_Der, Convention (Base_Type (Full_Parent)));
7050 -- Start of processing for Build_Derived_Private_Type
7053 if Is_Tagged_Type (Parent_Type) then
7054 Full_P := Full_View (Parent_Type);
7056 -- A type extension of a type with unknown discriminants is an
7057 -- indefinite type that the back-end cannot handle directly.
7058 -- We treat it as a private type, and build a completion that is
7059 -- derived from the full view of the parent, and hopefully has
7060 -- known discriminants.
7062 -- If the full view of the parent type has an underlying record view,
7063 -- use it to generate the underlying record view of this derived type
7064 -- (required for chains of derivations with unknown discriminants).
7066 -- Minor optimization: we avoid the generation of useless underlying
7067 -- record view entities if the private type declaration has unknown
7068 -- discriminants but its corresponding full view has no
7071 if Has_Unknown_Discriminants (Parent_Type)
7072 and then Present (Full_P)
7073 and then (Has_Discriminants (Full_P)
7074 or else Present (Underlying_Record_View (Full_P)))
7075 and then not In_Open_Scopes (Par_Scope)
7076 and then Expander_Active
7079 Full_Der : constant Entity_Id := Make_Temporary (Loc, 'T');
7080 New_Ext : constant Node_Id :=
7082 (Record_Extension_Part (Type_Definition (N)));
7086 Build_Derived_Record_Type
7087 (N, Parent_Type, Derived_Type, Derive_Subps);
7089 -- Build anonymous completion, as a derivation from the full
7090 -- view of the parent. This is not a completion in the usual
7091 -- sense, because the current type is not private.
7094 Make_Full_Type_Declaration (Loc,
7095 Defining_Identifier => Full_Der,
7097 Make_Derived_Type_Definition (Loc,
7098 Subtype_Indication =>
7100 (Subtype_Indication (Type_Definition (N))),
7101 Record_Extension_Part => New_Ext));
7103 -- If the parent type has an underlying record view, use it
7104 -- here to build the new underlying record view.
7106 if Present (Underlying_Record_View (Full_P)) then
7108 (Nkind (Subtype_Indication (Type_Definition (Decl)))
7110 Set_Entity (Subtype_Indication (Type_Definition (Decl)),
7111 Underlying_Record_View (Full_P));
7114 Install_Private_Declarations (Par_Scope);
7115 Install_Visible_Declarations (Par_Scope);
7116 Insert_Before (N, Decl);
7118 -- Mark entity as an underlying record view before analysis,
7119 -- to avoid generating the list of its primitive operations
7120 -- (which is not really required for this entity) and thus
7121 -- prevent spurious errors associated with missing overriding
7122 -- of abstract primitives (overridden only for Derived_Type).
7124 Set_Ekind (Full_Der, E_Record_Type);
7125 Set_Is_Underlying_Record_View (Full_Der);
7126 Set_Default_SSO (Full_Der);
7130 pragma Assert (Has_Discriminants (Full_Der)
7131 and then not Has_Unknown_Discriminants (Full_Der));
7133 Uninstall_Declarations (Par_Scope);
7135 -- Freeze the underlying record view, to prevent generation of
7136 -- useless dispatching information, which is simply shared with
7137 -- the real derived type.
7139 Set_Is_Frozen (Full_Der);
7141 -- If the derived type has access discriminants, create
7142 -- references to their anonymous types now, to prevent
7143 -- back-end problems when their first use is in generated
7144 -- bodies of primitives.
7150 E := First_Entity (Full_Der);
7152 while Present (E) loop
7153 if Ekind (E) = E_Discriminant
7154 and then Ekind (Etype (E)) = E_Anonymous_Access_Type
7156 Build_Itype_Reference (Etype (E), Decl);
7163 -- Set up links between real entity and underlying record view
7165 Set_Underlying_Record_View (Derived_Type, Base_Type (Full_Der));
7166 Set_Underlying_Record_View (Base_Type (Full_Der), Derived_Type);
7169 -- If discriminants are known, build derived record
7172 Build_Derived_Record_Type
7173 (N, Parent_Type, Derived_Type, Derive_Subps);
7178 elsif Has_Discriminants (Parent_Type) then
7180 -- Build partial view of derived type from partial view of parent.
7181 -- This must be done before building the full derivation because the
7182 -- second derivation will modify the discriminants of the first and
7183 -- the discriminants are chained with the rest of the components in
7184 -- the full derivation.
7186 Build_Derived_Record_Type
7187 (N, Parent_Type, Derived_Type, Derive_Subps);
7189 -- Build the full derivation if this is not the anonymous derived
7190 -- base type created by Build_Derived_Record_Type in the constrained
7191 -- case (see point 5. of its head comment) since we build it for the
7192 -- derived subtype. And skip it for protected types altogether, as
7193 -- gigi does not use these types directly.
7195 if Present (Full_View (Parent_Type))
7196 and then not Is_Itype (Derived_Type)
7197 and then not (Ekind (Full_View (Parent_Type)) in Protected_Kind)
7200 Der_Base : constant Entity_Id := Base_Type (Derived_Type);
7202 Last_Discr : Entity_Id;
7205 -- If this is not a completion, construct the implicit full
7206 -- view by deriving from the full view of the parent type.
7207 -- But if this is a completion, the derived private type
7208 -- being built is a full view and the full derivation can
7209 -- only be its underlying full view.
7211 Build_Full_Derivation;
7213 if not Is_Completion then
7214 Set_Full_View (Derived_Type, Full_Der);
7216 Set_Underlying_Full_View (Derived_Type, Full_Der);
7219 if not Is_Base_Type (Derived_Type) then
7220 Set_Full_View (Der_Base, Base_Type (Full_Der));
7223 -- Copy the discriminant list from full view to the partial
7224 -- view (base type and its subtype). Gigi requires that the
7225 -- partial and full views have the same discriminants.
7227 -- Note that since the partial view points to discriminants
7228 -- in the full view, their scope will be that of the full
7229 -- view. This might cause some front end problems and need
7232 Discr := First_Discriminant (Base_Type (Full_Der));
7233 Set_First_Entity (Der_Base, Discr);
7236 Last_Discr := Discr;
7237 Next_Discriminant (Discr);
7238 exit when No (Discr);
7241 Set_Last_Entity (Der_Base, Last_Discr);
7242 Set_First_Entity (Derived_Type, First_Entity (Der_Base));
7243 Set_Last_Entity (Derived_Type, Last_Entity (Der_Base));
7245 Set_Stored_Constraint
7246 (Full_Der, Stored_Constraint (Derived_Type));
7250 elsif Present (Full_View (Parent_Type))
7251 and then Has_Discriminants (Full_View (Parent_Type))
7253 if Has_Unknown_Discriminants (Parent_Type)
7254 and then Nkind (Subtype_Indication (Type_Definition (N))) =
7255 N_Subtype_Indication
7258 ("cannot constrain type with unknown discriminants",
7259 Subtype_Indication (Type_Definition (N)));
7263 -- If this is not a completion, construct the implicit full view by
7264 -- deriving from the full view of the parent type. But if this is a
7265 -- completion, the derived private type being built is a full view
7266 -- and the full derivation can only be its underlying full view.
7268 Build_Full_Derivation;
7270 if not Is_Completion then
7271 Set_Full_View (Derived_Type, Full_Der);
7273 Set_Underlying_Full_View (Derived_Type, Full_Der);
7276 -- In any case, the primitive operations are inherited from the
7277 -- parent type, not from the internal full view.
7279 Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type));
7281 if Derive_Subps then
7282 Derive_Subprograms (Parent_Type, Derived_Type);
7285 Set_Stored_Constraint (Derived_Type, No_Elist);
7287 (Derived_Type, Is_Constrained (Full_View (Parent_Type)));
7290 -- Untagged type, No discriminants on either view
7292 if Nkind (Subtype_Indication (Type_Definition (N))) =
7293 N_Subtype_Indication
7296 ("illegal constraint on type without discriminants", N);
7299 if Present (Discriminant_Specifications (N))
7300 and then Present (Full_View (Parent_Type))
7301 and then not Is_Tagged_Type (Full_View (Parent_Type))
7303 Error_Msg_N ("cannot add discriminants to untagged type", N);
7306 Set_Stored_Constraint (Derived_Type, No_Elist);
7307 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
7308 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
7309 Set_Disable_Controlled (Derived_Type, Disable_Controlled
7311 Set_Has_Controlled_Component
7312 (Derived_Type, Has_Controlled_Component
7315 -- Direct controlled types do not inherit Finalize_Storage_Only flag
7317 if not Is_Controlled_Active (Parent_Type) then
7318 Set_Finalize_Storage_Only
7319 (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type));
7322 -- If this is not a completion, construct the implicit full view by
7323 -- deriving from the full view of the parent type.
7325 -- ??? If the parent is untagged private and its completion is
7326 -- tagged, this mechanism will not work because we cannot derive from
7327 -- the tagged full view unless we have an extension.
7329 if Present (Full_View (Parent_Type))
7330 and then not Is_Tagged_Type (Full_View (Parent_Type))
7331 and then not Is_Completion
7333 Build_Full_Derivation;
7334 Set_Full_View (Derived_Type, Full_Der);
7338 Set_Has_Unknown_Discriminants (Derived_Type,
7339 Has_Unknown_Discriminants (Parent_Type));
7341 if Is_Private_Type (Derived_Type) then
7342 Set_Private_Dependents (Derived_Type, New_Elmt_List);
7345 -- If the parent base type is in scope, add the derived type to its
7346 -- list of private dependents, because its full view may become
7347 -- visible subsequently (in a nested private part, a body, or in a
7348 -- further child unit).
7350 if Is_Private_Type (Par_Base) and then In_Open_Scopes (Par_Scope) then
7351 Append_Elmt (Derived_Type, Private_Dependents (Parent_Type));
7353 -- Check for unusual case where a type completed by a private
7354 -- derivation occurs within a package nested in a child unit, and
7355 -- the parent is declared in an ancestor.
7357 if Is_Child_Unit (Scope (Current_Scope))
7358 and then Is_Completion
7359 and then In_Private_Part (Current_Scope)
7360 and then Scope (Parent_Type) /= Current_Scope
7362 -- Note that if the parent has a completion in the private part,
7363 -- (which is itself a derivation from some other private type)
7364 -- it is that completion that is visible, there is no full view
7365 -- available, and no special processing is needed.
7367 and then Present (Full_View (Parent_Type))
7369 -- In this case, the full view of the parent type will become
7370 -- visible in the body of the enclosing child, and only then will
7371 -- the current type be possibly non-private. Build an underlying
7372 -- full view that will be installed when the enclosing child body
7375 if Present (Underlying_Full_View (Derived_Type)) then
7376 Full_Der := Underlying_Full_View (Derived_Type);
7378 Build_Full_Derivation;
7379 Set_Underlying_Full_View (Derived_Type, Full_Der);
7382 -- The full view will be used to swap entities on entry/exit to
7383 -- the body, and must appear in the entity list for the package.
7385 Append_Entity (Full_Der, Scope (Derived_Type));
7388 end Build_Derived_Private_Type;
7390 -------------------------------
7391 -- Build_Derived_Record_Type --
7392 -------------------------------
7396 -- Ideally we would like to use the same model of type derivation for
7397 -- tagged and untagged record types. Unfortunately this is not quite
7398 -- possible because the semantics of representation clauses is different
7399 -- for tagged and untagged records under inheritance. Consider the
7402 -- type R (...) is [tagged] record ... end record;
7403 -- type T (...) is new R (...) [with ...];
7405 -- The representation clauses for T can specify a completely different
7406 -- record layout from R's. Hence the same component can be placed in two
7407 -- very different positions in objects of type T and R. If R and T are
7408 -- tagged types, representation clauses for T can only specify the layout
7409 -- of non inherited components, thus components that are common in R and T
7410 -- have the same position in objects of type R and T.
7412 -- This has two implications. The first is that the entire tree for R's
7413 -- declaration needs to be copied for T in the untagged case, so that T
7414 -- can be viewed as a record type of its own with its own representation
7415 -- clauses. The second implication is the way we handle discriminants.
7416 -- Specifically, in the untagged case we need a way to communicate to Gigi
7417 -- what are the real discriminants in the record, while for the semantics
7418 -- we need to consider those introduced by the user to rename the
7419 -- discriminants in the parent type. This is handled by introducing the
7420 -- notion of stored discriminants. See below for more.
7422 -- Fortunately the way regular components are inherited can be handled in
7423 -- the same way in tagged and untagged types.
7425 -- To complicate things a bit more the private view of a private extension
7426 -- cannot be handled in the same way as the full view (for one thing the
7427 -- semantic rules are somewhat different). We will explain what differs
7430 -- 2. DISCRIMINANTS UNDER INHERITANCE
7432 -- The semantic rules governing the discriminants of derived types are
7435 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
7436 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
7438 -- If parent type has discriminants, then the discriminants that are
7439 -- declared in the derived type are [3.4 (11)]:
7441 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
7444 -- o Otherwise, each discriminant of the parent type (implicitly declared
7445 -- in the same order with the same specifications). In this case, the
7446 -- discriminants are said to be "inherited", or if unknown in the parent
7447 -- are also unknown in the derived type.
7449 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
7451 -- o The parent subtype must be constrained;
7453 -- o If the parent type is not a tagged type, then each discriminant of
7454 -- the derived type must be used in the constraint defining a parent
7455 -- subtype. [Implementation note: This ensures that the new discriminant
7456 -- can share storage with an existing discriminant.]
7458 -- For the derived type each discriminant of the parent type is either
7459 -- inherited, constrained to equal some new discriminant of the derived
7460 -- type, or constrained to the value of an expression.
7462 -- When inherited or constrained to equal some new discriminant, the
7463 -- parent discriminant and the discriminant of the derived type are said
7466 -- If a discriminant of the parent type is constrained to a specific value
7467 -- in the derived type definition, then the discriminant is said to be
7468 -- "specified" by that derived type definition.
7470 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES
7472 -- We have spoken about stored discriminants in point 1 (introduction)
7473 -- above. There are two sort of stored discriminants: implicit and
7474 -- explicit. As long as the derived type inherits the same discriminants as
7475 -- the root record type, stored discriminants are the same as regular
7476 -- discriminants, and are said to be implicit. However, if any discriminant
7477 -- in the root type was renamed in the derived type, then the derived
7478 -- type will contain explicit stored discriminants. Explicit stored
7479 -- discriminants are discriminants in addition to the semantically visible
7480 -- discriminants defined for the derived type. Stored discriminants are
7481 -- used by Gigi to figure out what are the physical discriminants in
7482 -- objects of the derived type (see precise definition in einfo.ads).
7483 -- As an example, consider the following:
7485 -- type R (D1, D2, D3 : Int) is record ... end record;
7486 -- type T1 is new R;
7487 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
7488 -- type T3 is new T2;
7489 -- type T4 (Y : Int) is new T3 (Y, 99);
7491 -- The following table summarizes the discriminants and stored
7492 -- discriminants in R and T1 through T4.
7494 -- Type Discrim Stored Discrim Comment
7495 -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R
7496 -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1
7497 -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2
7498 -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3
7499 -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4
7501 -- Field Corresponding_Discriminant (abbreviated CD below) allows us to
7502 -- find the corresponding discriminant in the parent type, while
7503 -- Original_Record_Component (abbreviated ORC below), the actual physical
7504 -- component that is renamed. Finally the field Is_Completely_Hidden
7505 -- (abbreviated ICH below) is set for all explicit stored discriminants
7506 -- (see einfo.ads for more info). For the above example this gives:
7508 -- Discrim CD ORC ICH
7509 -- ^^^^^^^ ^^ ^^^ ^^^
7510 -- D1 in R empty itself no
7511 -- D2 in R empty itself no
7512 -- D3 in R empty itself no
7514 -- D1 in T1 D1 in R itself no
7515 -- D2 in T1 D2 in R itself no
7516 -- D3 in T1 D3 in R itself no
7518 -- X1 in T2 D3 in T1 D3 in T2 no
7519 -- X2 in T2 D1 in T1 D1 in T2 no
7520 -- D1 in T2 empty itself yes
7521 -- D2 in T2 empty itself yes
7522 -- D3 in T2 empty itself yes
7524 -- X1 in T3 X1 in T2 D3 in T3 no
7525 -- X2 in T3 X2 in T2 D1 in T3 no
7526 -- D1 in T3 empty itself yes
7527 -- D2 in T3 empty itself yes
7528 -- D3 in T3 empty itself yes
7530 -- Y in T4 X1 in T3 D3 in T3 no
7531 -- D1 in T3 empty itself yes
7532 -- D2 in T3 empty itself yes
7533 -- D3 in T3 empty itself yes
7535 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES
7537 -- Type derivation for tagged types is fairly straightforward. If no
7538 -- discriminants are specified by the derived type, these are inherited
7539 -- from the parent. No explicit stored discriminants are ever necessary.
7540 -- The only manipulation that is done to the tree is that of adding a
7541 -- _parent field with parent type and constrained to the same constraint
7542 -- specified for the parent in the derived type definition. For instance:
7544 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
7545 -- type T1 is new R with null record;
7546 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
7548 -- are changed into:
7550 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
7551 -- _parent : R (D1, D2, D3);
7554 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
7555 -- _parent : T1 (X2, 88, X1);
7558 -- The discriminants actually present in R, T1 and T2 as well as their CD,
7559 -- ORC and ICH fields are:
7561 -- Discrim CD ORC ICH
7562 -- ^^^^^^^ ^^ ^^^ ^^^
7563 -- D1 in R empty itself no
7564 -- D2 in R empty itself no
7565 -- D3 in R empty itself no
7567 -- D1 in T1 D1 in R D1 in R no
7568 -- D2 in T1 D2 in R D2 in R no
7569 -- D3 in T1 D3 in R D3 in R no
7571 -- X1 in T2 D3 in T1 D3 in R no
7572 -- X2 in T2 D1 in T1 D1 in R no
7574 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS
7576 -- Regardless of whether we dealing with a tagged or untagged type
7577 -- we will transform all derived type declarations of the form
7579 -- type T is new R (...) [with ...];
7581 -- subtype S is R (...);
7582 -- type T is new S [with ...];
7584 -- type BT is new R [with ...];
7585 -- subtype T is BT (...);
7587 -- That is, the base derived type is constrained only if it has no
7588 -- discriminants. The reason for doing this is that GNAT's semantic model
7589 -- assumes that a base type with discriminants is unconstrained.
7591 -- Note that, strictly speaking, the above transformation is not always
7592 -- correct. Consider for instance the following excerpt from ACVC b34011a:
7594 -- procedure B34011A is
7595 -- type REC (D : integer := 0) is record
7600 -- type T6 is new Rec;
7601 -- function F return T6;
7606 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
7609 -- The definition of Q6.U is illegal. However transforming Q6.U into
7611 -- type BaseU is new T6;
7612 -- subtype U is BaseU (Q6.F.I)
7614 -- turns U into a legal subtype, which is incorrect. To avoid this problem
7615 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
7616 -- the transformation described above.
7618 -- There is another instance where the above transformation is incorrect.
7622 -- type Base (D : Integer) is tagged null record;
7623 -- procedure P (X : Base);
7625 -- type Der is new Base (2) with null record;
7626 -- procedure P (X : Der);
7629 -- Then the above transformation turns this into
7631 -- type Der_Base is new Base with null record;
7632 -- -- procedure P (X : Base) is implicitly inherited here
7633 -- -- as procedure P (X : Der_Base).
7635 -- subtype Der is Der_Base (2);
7636 -- procedure P (X : Der);
7637 -- -- The overriding of P (X : Der_Base) is illegal since we
7638 -- -- have a parameter conformance problem.
7640 -- To get around this problem, after having semantically processed Der_Base
7641 -- and the rewritten subtype declaration for Der, we copy Der_Base field
7642 -- Discriminant_Constraint from Der so that when parameter conformance is
7643 -- checked when P is overridden, no semantic errors are flagged.
7645 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS
7647 -- Regardless of whether we are dealing with a tagged or untagged type
7648 -- we will transform all derived type declarations of the form
7650 -- type R (D1, .., Dn : ...) is [tagged] record ...;
7651 -- type T is new R [with ...];
7653 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
7655 -- The reason for such transformation is that it allows us to implement a
7656 -- very clean form of component inheritance as explained below.
7658 -- Note that this transformation is not achieved by direct tree rewriting
7659 -- and manipulation, but rather by redoing the semantic actions that the
7660 -- above transformation will entail. This is done directly in routine
7661 -- Inherit_Components.
7663 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE
7665 -- In both tagged and untagged derived types, regular non discriminant
7666 -- components are inherited in the derived type from the parent type. In
7667 -- the absence of discriminants component, inheritance is straightforward
7668 -- as components can simply be copied from the parent.
7670 -- If the parent has discriminants, inheriting components constrained with
7671 -- these discriminants requires caution. Consider the following example:
7673 -- type R (D1, D2 : Positive) is [tagged] record
7674 -- S : String (D1 .. D2);
7677 -- type T1 is new R [with null record];
7678 -- type T2 (X : positive) is new R (1, X) [with null record];
7680 -- As explained in 6. above, T1 is rewritten as
7681 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
7682 -- which makes the treatment for T1 and T2 identical.
7684 -- What we want when inheriting S, is that references to D1 and D2 in R are
7685 -- replaced with references to their correct constraints, i.e. D1 and D2 in
7686 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
7687 -- with either discriminant references in the derived type or expressions.
7688 -- This replacement is achieved as follows: before inheriting R's
7689 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
7690 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
7691 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
7692 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
7693 -- by String (1 .. X).
7695 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS
7697 -- We explain here the rules governing private type extensions relevant to
7698 -- type derivation. These rules are explained on the following example:
7700 -- type D [(...)] is new A [(...)] with private; <-- partial view
7701 -- type D [(...)] is new P [(...)] with null record; <-- full view
7703 -- Type A is called the ancestor subtype of the private extension.
7704 -- Type P is the parent type of the full view of the private extension. It
7705 -- must be A or a type derived from A.
7707 -- The rules concerning the discriminants of private type extensions are
7710 -- o If a private extension inherits known discriminants from the ancestor
7711 -- subtype, then the full view must also inherit its discriminants from
7712 -- the ancestor subtype and the parent subtype of the full view must be
7713 -- constrained if and only if the ancestor subtype is constrained.
7715 -- o If a partial view has unknown discriminants, then the full view may
7716 -- define a definite or an indefinite subtype, with or without
7719 -- o If a partial view has neither known nor unknown discriminants, then
7720 -- the full view must define a definite subtype.
7722 -- o If the ancestor subtype of a private extension has constrained
7723 -- discriminants, then the parent subtype of the full view must impose a
7724 -- statically matching constraint on those discriminants.
7726 -- This means that only the following forms of private extensions are
7729 -- type D is new A with private; <-- partial view
7730 -- type D is new P with null record; <-- full view
7732 -- If A has no discriminants than P has no discriminants, otherwise P must
7733 -- inherit A's discriminants.
7735 -- type D is new A (...) with private; <-- partial view
7736 -- type D is new P (:::) with null record; <-- full view
7738 -- P must inherit A's discriminants and (...) and (:::) must statically
7741 -- subtype A is R (...);
7742 -- type D is new A with private; <-- partial view
7743 -- type D is new P with null record; <-- full view
7745 -- P must have inherited R's discriminants and must be derived from A or
7746 -- any of its subtypes.
7748 -- type D (..) is new A with private; <-- partial view
7749 -- type D (..) is new P [(:::)] with null record; <-- full view
7751 -- No specific constraints on P's discriminants or constraint (:::).
7752 -- Note that A can be unconstrained, but the parent subtype P must either
7753 -- be constrained or (:::) must be present.
7755 -- type D (..) is new A [(...)] with private; <-- partial view
7756 -- type D (..) is new P [(:::)] with null record; <-- full view
7758 -- P's constraints on A's discriminants must statically match those
7759 -- imposed by (...).
7761 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS
7763 -- The full view of a private extension is handled exactly as described
7764 -- above. The model chose for the private view of a private extension is
7765 -- the same for what concerns discriminants (i.e. they receive the same
7766 -- treatment as in the tagged case). However, the private view of the
7767 -- private extension always inherits the components of the parent base,
7768 -- without replacing any discriminant reference. Strictly speaking this is
7769 -- incorrect. However, Gigi never uses this view to generate code so this
7770 -- is a purely semantic issue. In theory, a set of transformations similar
7771 -- to those given in 5. and 6. above could be applied to private views of
7772 -- private extensions to have the same model of component inheritance as
7773 -- for non private extensions. However, this is not done because it would
7774 -- further complicate private type processing. Semantically speaking, this
7775 -- leaves us in an uncomfortable situation. As an example consider:
7778 -- type R (D : integer) is tagged record
7779 -- S : String (1 .. D);
7781 -- procedure P (X : R);
7782 -- type T is new R (1) with private;
7784 -- type T is new R (1) with null record;
7787 -- This is transformed into:
7790 -- type R (D : integer) is tagged record
7791 -- S : String (1 .. D);
7793 -- procedure P (X : R);
7794 -- type T is new R (1) with private;
7796 -- type BaseT is new R with null record;
7797 -- subtype T is BaseT (1);
7800 -- (strictly speaking the above is incorrect Ada)
7802 -- From the semantic standpoint the private view of private extension T
7803 -- should be flagged as constrained since one can clearly have
7807 -- in a unit withing Pack. However, when deriving subprograms for the
7808 -- private view of private extension T, T must be seen as unconstrained
7809 -- since T has discriminants (this is a constraint of the current
7810 -- subprogram derivation model). Thus, when processing the private view of
7811 -- a private extension such as T, we first mark T as unconstrained, we
7812 -- process it, we perform program derivation and just before returning from
7813 -- Build_Derived_Record_Type we mark T as constrained.
7815 -- ??? Are there are other uncomfortable cases that we will have to
7818 -- 10. RECORD_TYPE_WITH_PRIVATE complications
7820 -- Types that are derived from a visible record type and have a private
7821 -- extension present other peculiarities. They behave mostly like private
7822 -- types, but if they have primitive operations defined, these will not
7823 -- have the proper signatures for further inheritance, because other
7824 -- primitive operations will use the implicit base that we define for
7825 -- private derivations below. This affect subprogram inheritance (see
7826 -- Derive_Subprograms for details). We also derive the implicit base from
7827 -- the base type of the full view, so that the implicit base is a record
7828 -- type and not another private type, This avoids infinite loops.
7830 procedure Build_Derived_Record_Type
7832 Parent_Type : Entity_Id;
7833 Derived_Type : Entity_Id;
7834 Derive_Subps : Boolean := True)
7836 Discriminant_Specs : constant Boolean :=
7837 Present (Discriminant_Specifications (N));
7838 Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type);
7839 Loc : constant Source_Ptr := Sloc (N);
7840 Private_Extension : constant Boolean :=
7841 Nkind (N) = N_Private_Extension_Declaration;
7842 Assoc_List : Elist_Id;
7843 Constraint_Present : Boolean;
7845 Discrim : Entity_Id;
7847 Inherit_Discrims : Boolean := False;
7848 Last_Discrim : Entity_Id;
7849 New_Base : Entity_Id;
7851 New_Discrs : Elist_Id;
7852 New_Indic : Node_Id;
7853 Parent_Base : Entity_Id;
7854 Save_Etype : Entity_Id;
7855 Save_Discr_Constr : Elist_Id;
7856 Save_Next_Entity : Entity_Id;
7859 Discs : Elist_Id := New_Elmt_List;
7860 -- An empty Discs list means that there were no constraints in the
7861 -- subtype indication or that there was an error processing it.
7864 if Ekind (Parent_Type) = E_Record_Type_With_Private
7865 and then Present (Full_View (Parent_Type))
7866 and then Has_Discriminants (Parent_Type)
7868 Parent_Base := Base_Type (Full_View (Parent_Type));
7870 Parent_Base := Base_Type (Parent_Type);
7873 -- AI05-0115 : if this is a derivation from a private type in some
7874 -- other scope that may lead to invisible components for the derived
7875 -- type, mark it accordingly.
7877 if Is_Private_Type (Parent_Type) then
7878 if Scope (Parent_Type) = Scope (Derived_Type) then
7881 elsif In_Open_Scopes (Scope (Parent_Type))
7882 and then In_Private_Part (Scope (Parent_Type))
7887 Set_Has_Private_Ancestor (Derived_Type);
7891 Set_Has_Private_Ancestor
7892 (Derived_Type, Has_Private_Ancestor (Parent_Type));
7895 -- Before we start the previously documented transformations, here is
7896 -- little fix for size and alignment of tagged types. Normally when we
7897 -- derive type D from type P, we copy the size and alignment of P as the
7898 -- default for D, and in the absence of explicit representation clauses
7899 -- for D, the size and alignment are indeed the same as the parent.
7901 -- But this is wrong for tagged types, since fields may be added, and
7902 -- the default size may need to be larger, and the default alignment may
7903 -- need to be larger.
7905 -- We therefore reset the size and alignment fields in the tagged case.
7906 -- Note that the size and alignment will in any case be at least as
7907 -- large as the parent type (since the derived type has a copy of the
7908 -- parent type in the _parent field)
7910 -- The type is also marked as being tagged here, which is needed when
7911 -- processing components with a self-referential anonymous access type
7912 -- in the call to Check_Anonymous_Access_Components below. Note that
7913 -- this flag is also set later on for completeness.
7916 Set_Is_Tagged_Type (Derived_Type);
7917 Init_Size_Align (Derived_Type);
7920 -- STEP 0a: figure out what kind of derived type declaration we have
7922 if Private_Extension then
7924 Set_Ekind (Derived_Type, E_Record_Type_With_Private);
7925 Set_Default_SSO (Derived_Type);
7928 Type_Def := Type_Definition (N);
7930 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
7931 -- Parent_Base can be a private type or private extension. However,
7932 -- for tagged types with an extension the newly added fields are
7933 -- visible and hence the Derived_Type is always an E_Record_Type.
7934 -- (except that the parent may have its own private fields).
7935 -- For untagged types we preserve the Ekind of the Parent_Base.
7937 if Present (Record_Extension_Part (Type_Def)) then
7938 Set_Ekind (Derived_Type, E_Record_Type);
7939 Set_Default_SSO (Derived_Type);
7941 -- Create internal access types for components with anonymous
7944 if Ada_Version >= Ada_2005 then
7945 Check_Anonymous_Access_Components
7946 (N, Derived_Type, Derived_Type,
7947 Component_List (Record_Extension_Part (Type_Def)));
7951 Set_Ekind (Derived_Type, Ekind (Parent_Base));
7955 -- Indic can either be an N_Identifier if the subtype indication
7956 -- contains no constraint or an N_Subtype_Indication if the subtype
7957 -- indication has a constraint.
7959 Indic := Subtype_Indication (Type_Def);
7960 Constraint_Present := (Nkind (Indic) = N_Subtype_Indication);
7962 -- Check that the type has visible discriminants. The type may be
7963 -- a private type with unknown discriminants whose full view has
7964 -- discriminants which are invisible.
7966 if Constraint_Present then
7967 if not Has_Discriminants (Parent_Base)
7969 (Has_Unknown_Discriminants (Parent_Base)
7970 and then Is_Private_Type (Parent_Base))
7973 ("invalid constraint: type has no discriminant",
7974 Constraint (Indic));
7976 Constraint_Present := False;
7977 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7979 elsif Is_Constrained (Parent_Type) then
7981 ("invalid constraint: parent type is already constrained",
7982 Constraint (Indic));
7984 Constraint_Present := False;
7985 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7989 -- STEP 0b: If needed, apply transformation given in point 5. above
7991 if not Private_Extension
7992 and then Has_Discriminants (Parent_Type)
7993 and then not Discriminant_Specs
7994 and then (Is_Constrained (Parent_Type) or else Constraint_Present)
7996 -- First, we must analyze the constraint (see comment in point 5.)
7997 -- The constraint may come from the subtype indication of the full
8000 if Constraint_Present then
8001 New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic);
8003 -- If there is no explicit constraint, there might be one that is
8004 -- inherited from a constrained parent type. In that case verify that
8005 -- it conforms to the constraint in the partial view. In perverse
8006 -- cases the parent subtypes of the partial and full view can have
8007 -- different constraints.
8009 elsif Present (Stored_Constraint (Parent_Type)) then
8010 New_Discrs := Stored_Constraint (Parent_Type);
8013 New_Discrs := No_Elist;
8016 if Has_Discriminants (Derived_Type)
8017 and then Has_Private_Declaration (Derived_Type)
8018 and then Present (Discriminant_Constraint (Derived_Type))
8019 and then Present (New_Discrs)
8021 -- Verify that constraints of the full view statically match
8022 -- those given in the partial view.
8028 C1 := First_Elmt (New_Discrs);
8029 C2 := First_Elmt (Discriminant_Constraint (Derived_Type));
8030 while Present (C1) and then Present (C2) loop
8031 if Fully_Conformant_Expressions (Node (C1), Node (C2))
8033 (Is_OK_Static_Expression (Node (C1))
8034 and then Is_OK_Static_Expression (Node (C2))
8036 Expr_Value (Node (C1)) = Expr_Value (Node (C2)))
8041 if Constraint_Present then
8043 ("constraint not conformant to previous declaration",
8047 ("constraint of full view is incompatible "
8048 & "with partial view", N);
8058 -- Insert and analyze the declaration for the unconstrained base type
8060 New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B');
8063 Make_Full_Type_Declaration (Loc,
8064 Defining_Identifier => New_Base,
8066 Make_Derived_Type_Definition (Loc,
8067 Abstract_Present => Abstract_Present (Type_Def),
8068 Limited_Present => Limited_Present (Type_Def),
8069 Subtype_Indication =>
8070 New_Occurrence_Of (Parent_Base, Loc),
8071 Record_Extension_Part =>
8072 Relocate_Node (Record_Extension_Part (Type_Def)),
8073 Interface_List => Interface_List (Type_Def)));
8075 Set_Parent (New_Decl, Parent (N));
8076 Mark_Rewrite_Insertion (New_Decl);
8077 Insert_Before (N, New_Decl);
8079 -- In the extension case, make sure ancestor is frozen appropriately
8080 -- (see also non-discriminated case below).
8082 if Present (Record_Extension_Part (Type_Def))
8083 or else Is_Interface (Parent_Base)
8085 Freeze_Before (New_Decl, Parent_Type);
8088 -- Note that this call passes False for the Derive_Subps parameter
8089 -- because subprogram derivation is deferred until after creating
8090 -- the subtype (see below).
8093 (New_Decl, Parent_Base, New_Base,
8094 Is_Completion => False, Derive_Subps => False);
8096 -- ??? This needs re-examination to determine whether the
8097 -- above call can simply be replaced by a call to Analyze.
8099 Set_Analyzed (New_Decl);
8101 -- Insert and analyze the declaration for the constrained subtype
8103 if Constraint_Present then
8105 Make_Subtype_Indication (Loc,
8106 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8107 Constraint => Relocate_Node (Constraint (Indic)));
8111 Constr_List : constant List_Id := New_List;
8116 C := First_Elmt (Discriminant_Constraint (Parent_Type));
8117 while Present (C) loop
8120 -- It is safe here to call New_Copy_Tree since we called
8121 -- Force_Evaluation on each constraint previously
8122 -- in Build_Discriminant_Constraints.
8124 Append (New_Copy_Tree (Expr), To => Constr_List);
8130 Make_Subtype_Indication (Loc,
8131 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8133 Make_Index_Or_Discriminant_Constraint (Loc, Constr_List));
8138 Make_Subtype_Declaration (Loc,
8139 Defining_Identifier => Derived_Type,
8140 Subtype_Indication => New_Indic));
8144 -- Derivation of subprograms must be delayed until the full subtype
8145 -- has been established, to ensure proper overriding of subprograms
8146 -- inherited by full types. If the derivations occurred as part of
8147 -- the call to Build_Derived_Type above, then the check for type
8148 -- conformance would fail because earlier primitive subprograms
8149 -- could still refer to the full type prior the change to the new
8150 -- subtype and hence would not match the new base type created here.
8151 -- Subprograms are not derived, however, when Derive_Subps is False
8152 -- (since otherwise there could be redundant derivations).
8154 if Derive_Subps then
8155 Derive_Subprograms (Parent_Type, Derived_Type);
8158 -- For tagged types the Discriminant_Constraint of the new base itype
8159 -- is inherited from the first subtype so that no subtype conformance
8160 -- problem arise when the first subtype overrides primitive
8161 -- operations inherited by the implicit base type.
8164 Set_Discriminant_Constraint
8165 (New_Base, Discriminant_Constraint (Derived_Type));
8171 -- If we get here Derived_Type will have no discriminants or it will be
8172 -- a discriminated unconstrained base type.
8174 -- STEP 1a: perform preliminary actions/checks for derived tagged types
8178 -- The parent type is frozen for non-private extensions (RM 13.14(7))
8179 -- The declaration of a specific descendant of an interface type
8180 -- freezes the interface type (RM 13.14).
8182 if not Private_Extension or else Is_Interface (Parent_Base) then
8183 Freeze_Before (N, Parent_Type);
8186 -- In Ada 2005 (AI-344), the restriction that a derived tagged type
8187 -- cannot be declared at a deeper level than its parent type is
8188 -- removed. The check on derivation within a generic body is also
8189 -- relaxed, but there's a restriction that a derived tagged type
8190 -- cannot be declared in a generic body if it's derived directly
8191 -- or indirectly from a formal type of that generic.
8193 if Ada_Version >= Ada_2005 then
8194 if Present (Enclosing_Generic_Body (Derived_Type)) then
8196 Ancestor_Type : Entity_Id;
8199 -- Check to see if any ancestor of the derived type is a
8202 Ancestor_Type := Parent_Type;
8203 while not Is_Generic_Type (Ancestor_Type)
8204 and then Etype (Ancestor_Type) /= Ancestor_Type
8206 Ancestor_Type := Etype (Ancestor_Type);
8209 -- If the derived type does have a formal type as an
8210 -- ancestor, then it's an error if the derived type is
8211 -- declared within the body of the generic unit that
8212 -- declares the formal type in its generic formal part. It's
8213 -- sufficient to check whether the ancestor type is declared
8214 -- inside the same generic body as the derived type (such as
8215 -- within a nested generic spec), in which case the
8216 -- derivation is legal. If the formal type is declared
8217 -- outside of that generic body, then it's guaranteed that
8218 -- the derived type is declared within the generic body of
8219 -- the generic unit declaring the formal type.
8221 if Is_Generic_Type (Ancestor_Type)
8222 and then Enclosing_Generic_Body (Ancestor_Type) /=
8223 Enclosing_Generic_Body (Derived_Type)
8226 ("parent type of& must not be descendant of formal type"
8227 & " of an enclosing generic body",
8228 Indic, Derived_Type);
8233 elsif Type_Access_Level (Derived_Type) /=
8234 Type_Access_Level (Parent_Type)
8235 and then not Is_Generic_Type (Derived_Type)
8237 if Is_Controlled (Parent_Type) then
8239 ("controlled type must be declared at the library level",
8243 ("type extension at deeper accessibility level than parent",
8249 GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type);
8252 and then GB /= Enclosing_Generic_Body (Parent_Base)
8255 ("parent type of& must not be outside generic body"
8257 Indic, Derived_Type);
8263 -- Ada 2005 (AI-251)
8265 if Ada_Version >= Ada_2005 and then Is_Tagged then
8267 -- "The declaration of a specific descendant of an interface type
8268 -- freezes the interface type" (RM 13.14).
8273 if Is_Non_Empty_List (Interface_List (Type_Def)) then
8274 Iface := First (Interface_List (Type_Def));
8275 while Present (Iface) loop
8276 Freeze_Before (N, Etype (Iface));
8283 -- STEP 1b : preliminary cleanup of the full view of private types
8285 -- If the type is already marked as having discriminants, then it's the
8286 -- completion of a private type or private extension and we need to
8287 -- retain the discriminants from the partial view if the current
8288 -- declaration has Discriminant_Specifications so that we can verify
8289 -- conformance. However, we must remove any existing components that
8290 -- were inherited from the parent (and attached in Copy_And_Swap)
8291 -- because the full type inherits all appropriate components anyway, and
8292 -- we do not want the partial view's components interfering.
8294 if Has_Discriminants (Derived_Type) and then Discriminant_Specs then
8295 Discrim := First_Discriminant (Derived_Type);
8297 Last_Discrim := Discrim;
8298 Next_Discriminant (Discrim);
8299 exit when No (Discrim);
8302 Set_Last_Entity (Derived_Type, Last_Discrim);
8304 -- In all other cases wipe out the list of inherited components (even
8305 -- inherited discriminants), it will be properly rebuilt here.
8308 Set_First_Entity (Derived_Type, Empty);
8309 Set_Last_Entity (Derived_Type, Empty);
8312 -- STEP 1c: Initialize some flags for the Derived_Type
8314 -- The following flags must be initialized here so that
8315 -- Process_Discriminants can check that discriminants of tagged types do
8316 -- not have a default initial value and that access discriminants are
8317 -- only specified for limited records. For completeness, these flags are
8318 -- also initialized along with all the other flags below.
8320 -- AI-419: Limitedness is not inherited from an interface parent, so to
8321 -- be limited in that case the type must be explicitly declared as
8322 -- limited. However, task and protected interfaces are always limited.
8324 if Limited_Present (Type_Def) then
8325 Set_Is_Limited_Record (Derived_Type);
8327 elsif Is_Limited_Record (Parent_Type)
8328 or else (Present (Full_View (Parent_Type))
8329 and then Is_Limited_Record (Full_View (Parent_Type)))
8331 if not Is_Interface (Parent_Type)
8332 or else Is_Synchronized_Interface (Parent_Type)
8333 or else Is_Protected_Interface (Parent_Type)
8334 or else Is_Task_Interface (Parent_Type)
8336 Set_Is_Limited_Record (Derived_Type);
8340 -- STEP 2a: process discriminants of derived type if any
8342 Push_Scope (Derived_Type);
8344 if Discriminant_Specs then
8345 Set_Has_Unknown_Discriminants (Derived_Type, False);
8347 -- The following call initializes fields Has_Discriminants and
8348 -- Discriminant_Constraint, unless we are processing the completion
8349 -- of a private type declaration.
8351 Check_Or_Process_Discriminants (N, Derived_Type);
8353 -- For untagged types, the constraint on the Parent_Type must be
8354 -- present and is used to rename the discriminants.
8356 if not Is_Tagged and then not Has_Discriminants (Parent_Type) then
8357 Error_Msg_N ("untagged parent must have discriminants", Indic);
8359 elsif not Is_Tagged and then not Constraint_Present then
8361 ("discriminant constraint needed for derived untagged records",
8364 -- Otherwise the parent subtype must be constrained unless we have a
8365 -- private extension.
8367 elsif not Constraint_Present
8368 and then not Private_Extension
8369 and then not Is_Constrained (Parent_Type)
8372 ("unconstrained type not allowed in this context", Indic);
8374 elsif Constraint_Present then
8375 -- The following call sets the field Corresponding_Discriminant
8376 -- for the discriminants in the Derived_Type.
8378 Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True);
8380 -- For untagged types all new discriminants must rename
8381 -- discriminants in the parent. For private extensions new
8382 -- discriminants cannot rename old ones (implied by [7.3(13)]).
8384 Discrim := First_Discriminant (Derived_Type);
8385 while Present (Discrim) loop
8387 and then No (Corresponding_Discriminant (Discrim))
8390 ("new discriminants must constrain old ones", Discrim);
8392 elsif Private_Extension
8393 and then Present (Corresponding_Discriminant (Discrim))
8396 ("only static constraints allowed for parent"
8397 & " discriminants in the partial view", Indic);
8401 -- If a new discriminant is used in the constraint, then its
8402 -- subtype must be statically compatible with the parent
8403 -- discriminant's subtype (3.7(15)).
8405 -- However, if the record contains an array constrained by
8406 -- the discriminant but with some different bound, the compiler
8407 -- attemps to create a smaller range for the discriminant type.
8408 -- (See exp_ch3.Adjust_Discriminants). In this case, where
8409 -- the discriminant type is a scalar type, the check must use
8410 -- the original discriminant type in the parent declaration.
8413 Corr_Disc : constant Entity_Id :=
8414 Corresponding_Discriminant (Discrim);
8415 Disc_Type : constant Entity_Id := Etype (Discrim);
8416 Corr_Type : Entity_Id;
8419 if Present (Corr_Disc) then
8420 if Is_Scalar_Type (Disc_Type) then
8422 Entity (Discriminant_Type (Parent (Corr_Disc)));
8424 Corr_Type := Etype (Corr_Disc);
8428 Subtypes_Statically_Compatible (Disc_Type, Corr_Type)
8431 ("subtype must be compatible "
8432 & "with parent discriminant",
8438 Next_Discriminant (Discrim);
8441 -- Check whether the constraints of the full view statically
8442 -- match those imposed by the parent subtype [7.3(13)].
8444 if Present (Stored_Constraint (Derived_Type)) then
8449 C1 := First_Elmt (Discs);
8450 C2 := First_Elmt (Stored_Constraint (Derived_Type));
8451 while Present (C1) and then Present (C2) loop
8453 Fully_Conformant_Expressions (Node (C1), Node (C2))
8456 ("not conformant with previous declaration",
8467 -- STEP 2b: No new discriminants, inherit discriminants if any
8470 if Private_Extension then
8471 Set_Has_Unknown_Discriminants
8473 Has_Unknown_Discriminants (Parent_Type)
8474 or else Unknown_Discriminants_Present (N));
8476 -- The partial view of the parent may have unknown discriminants,
8477 -- but if the full view has discriminants and the parent type is
8478 -- in scope they must be inherited.
8480 elsif Has_Unknown_Discriminants (Parent_Type)
8482 (not Has_Discriminants (Parent_Type)
8483 or else not In_Open_Scopes (Scope (Parent_Type)))
8485 Set_Has_Unknown_Discriminants (Derived_Type);
8488 if not Has_Unknown_Discriminants (Derived_Type)
8489 and then not Has_Unknown_Discriminants (Parent_Base)
8490 and then Has_Discriminants (Parent_Type)
8492 Inherit_Discrims := True;
8493 Set_Has_Discriminants
8494 (Derived_Type, True);
8495 Set_Discriminant_Constraint
8496 (Derived_Type, Discriminant_Constraint (Parent_Base));
8499 -- The following test is true for private types (remember
8500 -- transformation 5. is not applied to those) and in an error
8503 if Constraint_Present then
8504 Discs := Build_Discriminant_Constraints (Parent_Type, Indic);
8507 -- For now mark a new derived type as constrained only if it has no
8508 -- discriminants. At the end of Build_Derived_Record_Type we properly
8509 -- set this flag in the case of private extensions. See comments in
8510 -- point 9. just before body of Build_Derived_Record_Type.
8514 not (Inherit_Discrims
8515 or else Has_Unknown_Discriminants (Derived_Type)));
8518 -- STEP 3: initialize fields of derived type
8520 Set_Is_Tagged_Type (Derived_Type, Is_Tagged);
8521 Set_Stored_Constraint (Derived_Type, No_Elist);
8523 -- Ada 2005 (AI-251): Private type-declarations can implement interfaces
8524 -- but cannot be interfaces
8526 if not Private_Extension
8527 and then Ekind (Derived_Type) /= E_Private_Type
8528 and then Ekind (Derived_Type) /= E_Limited_Private_Type
8530 if Interface_Present (Type_Def) then
8531 Analyze_Interface_Declaration (Derived_Type, Type_Def);
8534 Set_Interfaces (Derived_Type, No_Elist);
8537 -- Fields inherited from the Parent_Type
8539 Set_Has_Specified_Layout
8540 (Derived_Type, Has_Specified_Layout (Parent_Type));
8541 Set_Is_Limited_Composite
8542 (Derived_Type, Is_Limited_Composite (Parent_Type));
8543 Set_Is_Private_Composite
8544 (Derived_Type, Is_Private_Composite (Parent_Type));
8546 if Is_Tagged_Type (Parent_Type) then
8547 Set_No_Tagged_Streams_Pragma
8548 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
8551 -- Fields inherited from the Parent_Base
8553 Set_Has_Controlled_Component
8554 (Derived_Type, Has_Controlled_Component (Parent_Base));
8555 Set_Has_Non_Standard_Rep
8556 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8557 Set_Has_Primitive_Operations
8558 (Derived_Type, Has_Primitive_Operations (Parent_Base));
8560 -- Fields inherited from the Parent_Base in the non-private case
8562 if Ekind (Derived_Type) = E_Record_Type then
8563 Set_Has_Complex_Representation
8564 (Derived_Type, Has_Complex_Representation (Parent_Base));
8567 -- Fields inherited from the Parent_Base for record types
8569 if Is_Record_Type (Derived_Type) then
8571 Parent_Full : Entity_Id;
8574 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
8575 -- Parent_Base can be a private type or private extension. Go
8576 -- to the full view here to get the E_Record_Type specific flags.
8578 if Present (Full_View (Parent_Base)) then
8579 Parent_Full := Full_View (Parent_Base);
8581 Parent_Full := Parent_Base;
8584 Set_OK_To_Reorder_Components
8585 (Derived_Type, OK_To_Reorder_Components (Parent_Full));
8589 -- Set fields for private derived types
8591 if Is_Private_Type (Derived_Type) then
8592 Set_Depends_On_Private (Derived_Type, True);
8593 Set_Private_Dependents (Derived_Type, New_Elmt_List);
8595 -- Inherit fields from non private record types. If this is the
8596 -- completion of a derivation from a private type, the parent itself
8597 -- is private, and the attributes come from its full view, which must
8601 if Is_Private_Type (Parent_Base)
8602 and then not Is_Record_Type (Parent_Base)
8604 Set_Component_Alignment
8605 (Derived_Type, Component_Alignment (Full_View (Parent_Base)));
8607 (Derived_Type, C_Pass_By_Copy (Full_View (Parent_Base)));
8609 Set_Component_Alignment
8610 (Derived_Type, Component_Alignment (Parent_Base));
8612 (Derived_Type, C_Pass_By_Copy (Parent_Base));
8616 -- Set fields for tagged types
8619 Set_Direct_Primitive_Operations (Derived_Type, New_Elmt_List);
8621 -- All tagged types defined in Ada.Finalization are controlled
8623 if Chars (Scope (Derived_Type)) = Name_Finalization
8624 and then Chars (Scope (Scope (Derived_Type))) = Name_Ada
8625 and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard
8627 Set_Is_Controlled (Derived_Type);
8629 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Base));
8632 -- Minor optimization: there is no need to generate the class-wide
8633 -- entity associated with an underlying record view.
8635 if not Is_Underlying_Record_View (Derived_Type) then
8636 Make_Class_Wide_Type (Derived_Type);
8639 Set_Is_Abstract_Type (Derived_Type, Abstract_Present (Type_Def));
8641 if Has_Discriminants (Derived_Type)
8642 and then Constraint_Present
8644 Set_Stored_Constraint
8645 (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs));
8648 if Ada_Version >= Ada_2005 then
8650 Ifaces_List : Elist_Id;
8653 -- Checks rules 3.9.4 (13/2 and 14/2)
8655 if Comes_From_Source (Derived_Type)
8656 and then not Is_Private_Type (Derived_Type)
8657 and then Is_Interface (Parent_Type)
8658 and then not Is_Interface (Derived_Type)
8660 if Is_Task_Interface (Parent_Type) then
8662 ("(Ada 2005) task type required (RM 3.9.4 (13.2))",
8665 elsif Is_Protected_Interface (Parent_Type) then
8667 ("(Ada 2005) protected type required (RM 3.9.4 (14.2))",
8672 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
8674 Check_Interfaces (N, Type_Def);
8676 -- Ada 2005 (AI-251): Collect the list of progenitors that are
8677 -- not already in the parents.
8681 Ifaces_List => Ifaces_List,
8682 Exclude_Parents => True);
8684 Set_Interfaces (Derived_Type, Ifaces_List);
8686 -- If the derived type is the anonymous type created for
8687 -- a declaration whose parent has a constraint, propagate
8688 -- the interface list to the source type. This must be done
8689 -- prior to the completion of the analysis of the source type
8690 -- because the components in the extension may contain current
8691 -- instances whose legality depends on some ancestor.
8693 if Is_Itype (Derived_Type) then
8695 Def : constant Node_Id :=
8696 Associated_Node_For_Itype (Derived_Type);
8699 and then Nkind (Def) = N_Full_Type_Declaration
8702 (Defining_Identifier (Def), Ifaces_List);
8707 -- Propagate inherited invariant information of parents
8710 if Ada_Version >= Ada_2012
8711 and then not Is_Interface (Derived_Type)
8713 if Has_Inheritable_Invariants (Parent_Type) then
8714 Set_Has_Invariants (Derived_Type);
8715 Set_Has_Inheritable_Invariants (Derived_Type);
8717 elsif not Is_Empty_Elmt_List (Ifaces_List) then
8722 AI := First_Elmt (Ifaces_List);
8723 while Present (AI) loop
8724 if Has_Inheritable_Invariants (Node (AI)) then
8725 Set_Has_Invariants (Derived_Type);
8726 Set_Has_Inheritable_Invariants (Derived_Type);
8737 -- A type extension is automatically Ghost when one of its
8738 -- progenitors is Ghost (SPARK RM 6.9(9)). This property is
8739 -- also inherited when the parent type is Ghost, but this is
8740 -- done in Build_Derived_Type as the mechanism also handles
8741 -- untagged derivations.
8743 if Implements_Ghost_Interface (Derived_Type) then
8744 Set_Is_Ghost_Entity (Derived_Type);
8750 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Base));
8751 Set_Has_Non_Standard_Rep
8752 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8755 -- STEP 4: Inherit components from the parent base and constrain them.
8756 -- Apply the second transformation described in point 6. above.
8758 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
8759 or else not Has_Discriminants (Parent_Type)
8760 or else not Is_Constrained (Parent_Type)
8764 Constrs := Discriminant_Constraint (Parent_Type);
8769 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
8771 -- STEP 5a: Copy the parent record declaration for untagged types
8773 if not Is_Tagged then
8775 -- Discriminant_Constraint (Derived_Type) has been properly
8776 -- constructed. Save it and temporarily set it to Empty because we
8777 -- do not want the call to New_Copy_Tree below to mess this list.
8779 if Has_Discriminants (Derived_Type) then
8780 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
8781 Set_Discriminant_Constraint (Derived_Type, No_Elist);
8783 Save_Discr_Constr := No_Elist;
8786 -- Save the Etype field of Derived_Type. It is correctly set now,
8787 -- but the call to New_Copy tree may remap it to point to itself,
8788 -- which is not what we want. Ditto for the Next_Entity field.
8790 Save_Etype := Etype (Derived_Type);
8791 Save_Next_Entity := Next_Entity (Derived_Type);
8793 -- Assoc_List maps all stored discriminants in the Parent_Base to
8794 -- stored discriminants in the Derived_Type. It is fundamental that
8795 -- no types or itypes with discriminants other than the stored
8796 -- discriminants appear in the entities declared inside
8797 -- Derived_Type, since the back end cannot deal with it.
8801 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
8803 -- Restore the fields saved prior to the New_Copy_Tree call
8804 -- and compute the stored constraint.
8806 Set_Etype (Derived_Type, Save_Etype);
8807 Set_Next_Entity (Derived_Type, Save_Next_Entity);
8809 if Has_Discriminants (Derived_Type) then
8810 Set_Discriminant_Constraint
8811 (Derived_Type, Save_Discr_Constr);
8812 Set_Stored_Constraint
8813 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
8814 Replace_Components (Derived_Type, New_Decl);
8815 Set_Has_Implicit_Dereference
8816 (Derived_Type, Has_Implicit_Dereference (Parent_Type));
8819 -- Insert the new derived type declaration
8821 Rewrite (N, New_Decl);
8823 -- STEP 5b: Complete the processing for record extensions in generics
8825 -- There is no completion for record extensions declared in the
8826 -- parameter part of a generic, so we need to complete processing for
8827 -- these generic record extensions here. The Record_Type_Definition call
8828 -- will change the Ekind of the components from E_Void to E_Component.
8830 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
8831 Record_Type_Definition (Empty, Derived_Type);
8833 -- STEP 5c: Process the record extension for non private tagged types
8835 elsif not Private_Extension then
8836 Expand_Record_Extension (Derived_Type, Type_Def);
8838 -- Note : previously in ASIS mode we set the Parent_Subtype of the
8839 -- derived type to propagate some semantic information. This led
8840 -- to other ASIS failures and has been removed.
8842 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
8843 -- implemented interfaces if we are in expansion mode
8846 and then Has_Interfaces (Derived_Type)
8848 Add_Interface_Tag_Components (N, Derived_Type);
8851 -- Analyze the record extension
8853 Record_Type_Definition
8854 (Record_Extension_Part (Type_Def), Derived_Type);
8859 -- Nothing else to do if there is an error in the derivation.
8860 -- An unusual case: the full view may be derived from a type in an
8861 -- instance, when the partial view was used illegally as an actual
8862 -- in that instance, leading to a circular definition.
8864 if Etype (Derived_Type) = Any_Type
8865 or else Etype (Parent_Type) = Derived_Type
8870 -- Set delayed freeze and then derive subprograms, we need to do
8871 -- this in this order so that derived subprograms inherit the
8872 -- derived freeze if necessary.
8874 Set_Has_Delayed_Freeze (Derived_Type);
8876 if Derive_Subps then
8877 Derive_Subprograms (Parent_Type, Derived_Type);
8880 -- If we have a private extension which defines a constrained derived
8881 -- type mark as constrained here after we have derived subprograms. See
8882 -- comment on point 9. just above the body of Build_Derived_Record_Type.
8884 if Private_Extension and then Inherit_Discrims then
8885 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
8886 Set_Is_Constrained (Derived_Type, True);
8887 Set_Discriminant_Constraint (Derived_Type, Discs);
8889 elsif Is_Constrained (Parent_Type) then
8891 (Derived_Type, True);
8892 Set_Discriminant_Constraint
8893 (Derived_Type, Discriminant_Constraint (Parent_Type));
8897 -- Update the class-wide type, which shares the now-completed entity
8898 -- list with its specific type. In case of underlying record views,
8899 -- we do not generate the corresponding class wide entity.
8902 and then not Is_Underlying_Record_View (Derived_Type)
8905 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
8907 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
8910 Check_Function_Writable_Actuals (N);
8911 end Build_Derived_Record_Type;
8913 ------------------------
8914 -- Build_Derived_Type --
8915 ------------------------
8917 procedure Build_Derived_Type
8919 Parent_Type : Entity_Id;
8920 Derived_Type : Entity_Id;
8921 Is_Completion : Boolean;
8922 Derive_Subps : Boolean := True)
8924 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
8927 -- Set common attributes
8929 Set_Scope (Derived_Type, Current_Scope);
8931 Set_Etype (Derived_Type, Parent_Base);
8932 Set_Ekind (Derived_Type, Ekind (Parent_Base));
8933 Set_Has_Task (Derived_Type, Has_Task (Parent_Base));
8934 Set_Has_Protected (Derived_Type, Has_Protected (Parent_Base));
8936 Set_Size_Info (Derived_Type, Parent_Type);
8937 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
8938 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
8939 Set_Disable_Controlled (Derived_Type, Disable_Controlled (Parent_Type));
8941 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
8942 Set_Is_Volatile (Derived_Type, Is_Volatile (Parent_Type));
8944 if Is_Tagged_Type (Derived_Type) then
8945 Set_No_Tagged_Streams_Pragma
8946 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
8949 -- If the parent has primitive routines, set the derived type link
8951 if Has_Primitive_Operations (Parent_Type) then
8952 Set_Derived_Type_Link (Parent_Base, Derived_Type);
8955 -- If the parent type is a private subtype, the convention on the base
8956 -- type may be set in the private part, and not propagated to the
8957 -- subtype until later, so we obtain the convention from the base type.
8959 Set_Convention (Derived_Type, Convention (Parent_Base));
8961 -- Set SSO default for record or array type
8963 if (Is_Array_Type (Derived_Type) or else Is_Record_Type (Derived_Type))
8964 and then Is_Base_Type (Derived_Type)
8966 Set_Default_SSO (Derived_Type);
8969 -- Propagate invariant information. The new type has invariants if
8970 -- they are inherited from the parent type, and these invariants can
8971 -- be further inherited, so both flags are set.
8973 -- We similarly inherit predicates
8975 if Has_Predicates (Parent_Type) then
8976 Set_Has_Predicates (Derived_Type);
8979 -- The derived type inherits the representation clauses of the parent
8981 Inherit_Rep_Item_Chain (Derived_Type, Parent_Type);
8983 -- Propagate the attributes related to pragma Default_Initial_Condition
8984 -- from the parent type to the private extension. A derived type always
8985 -- inherits the default initial condition flag from the parent type. If
8986 -- the derived type carries its own Default_Initial_Condition pragma,
8987 -- the flag is later reset in Analyze_Pragma. Note that both flags are
8988 -- mutually exclusive.
8990 Propagate_Default_Init_Cond_Attributes
8991 (From_Typ => Parent_Type,
8992 To_Typ => Derived_Type,
8993 Parent_To_Derivation => True);
8995 -- If the parent type has delayed rep aspects, then mark the derived
8996 -- type as possibly inheriting a delayed rep aspect.
8998 if Has_Delayed_Rep_Aspects (Parent_Type) then
8999 Set_May_Inherit_Delayed_Rep_Aspects (Derived_Type);
9002 -- Propagate the attributes related to pragma Ghost from the parent type
9003 -- to the derived type or type extension (SPARK RM 6.9(9)).
9005 if Is_Ghost_Entity (Parent_Type) then
9006 Set_Is_Ghost_Entity (Derived_Type);
9009 -- Type dependent processing
9011 case Ekind (Parent_Type) is
9012 when Numeric_Kind =>
9013 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
9016 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
9020 | Class_Wide_Kind =>
9021 Build_Derived_Record_Type
9022 (N, Parent_Type, Derived_Type, Derive_Subps);
9025 when Enumeration_Kind =>
9026 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
9029 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
9031 when Incomplete_Or_Private_Kind =>
9032 Build_Derived_Private_Type
9033 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
9035 -- For discriminated types, the derivation includes deriving
9036 -- primitive operations. For others it is done below.
9038 if Is_Tagged_Type (Parent_Type)
9039 or else Has_Discriminants (Parent_Type)
9040 or else (Present (Full_View (Parent_Type))
9041 and then Has_Discriminants (Full_View (Parent_Type)))
9046 when Concurrent_Kind =>
9047 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
9050 raise Program_Error;
9053 -- Nothing more to do if some error occurred
9055 if Etype (Derived_Type) = Any_Type then
9059 -- Set delayed freeze and then derive subprograms, we need to do this
9060 -- in this order so that derived subprograms inherit the derived freeze
9063 Set_Has_Delayed_Freeze (Derived_Type);
9065 if Derive_Subps then
9066 Derive_Subprograms (Parent_Type, Derived_Type);
9069 Set_Has_Primitive_Operations
9070 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
9071 end Build_Derived_Type;
9073 -----------------------
9074 -- Build_Discriminal --
9075 -----------------------
9077 procedure Build_Discriminal (Discrim : Entity_Id) is
9078 D_Minal : Entity_Id;
9079 CR_Disc : Entity_Id;
9082 -- A discriminal has the same name as the discriminant
9084 D_Minal := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
9086 Set_Ekind (D_Minal, E_In_Parameter);
9087 Set_Mechanism (D_Minal, Default_Mechanism);
9088 Set_Etype (D_Minal, Etype (Discrim));
9089 Set_Scope (D_Minal, Current_Scope);
9091 Set_Discriminal (Discrim, D_Minal);
9092 Set_Discriminal_Link (D_Minal, Discrim);
9094 -- For task types, build at once the discriminants of the corresponding
9095 -- record, which are needed if discriminants are used in entry defaults
9096 -- and in family bounds.
9098 if Is_Concurrent_Type (Current_Scope)
9100 Is_Limited_Type (Current_Scope)
9102 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
9104 Set_Ekind (CR_Disc, E_In_Parameter);
9105 Set_Mechanism (CR_Disc, Default_Mechanism);
9106 Set_Etype (CR_Disc, Etype (Discrim));
9107 Set_Scope (CR_Disc, Current_Scope);
9108 Set_Discriminal_Link (CR_Disc, Discrim);
9109 Set_CR_Discriminant (Discrim, CR_Disc);
9111 end Build_Discriminal;
9113 ------------------------------------
9114 -- Build_Discriminant_Constraints --
9115 ------------------------------------
9117 function Build_Discriminant_Constraints
9120 Derived_Def : Boolean := False) return Elist_Id
9122 C : constant Node_Id := Constraint (Def);
9123 Nb_Discr : constant Nat := Number_Discriminants (T);
9125 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
9126 -- Saves the expression corresponding to a given discriminant in T
9128 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
9129 -- Return the Position number within array Discr_Expr of a discriminant
9130 -- D within the discriminant list of the discriminated type T.
9132 procedure Process_Discriminant_Expression
9135 -- If this is a discriminant constraint on a partial view, do not
9136 -- generate an overflow check on the discriminant expression. The check
9137 -- will be generated when constraining the full view. Otherwise the
9138 -- backend creates duplicate symbols for the temporaries corresponding
9139 -- to the expressions to be checked, causing spurious assembler errors.
9145 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
9149 Disc := First_Discriminant (T);
9150 for J in Discr_Expr'Range loop
9155 Next_Discriminant (Disc);
9158 -- Note: Since this function is called on discriminants that are
9159 -- known to belong to the discriminated type, falling through the
9160 -- loop with no match signals an internal compiler error.
9162 raise Program_Error;
9165 -------------------------------------
9166 -- Process_Discriminant_Expression --
9167 -------------------------------------
9169 procedure Process_Discriminant_Expression
9173 BDT : constant Entity_Id := Base_Type (Etype (D));
9176 -- If this is a discriminant constraint on a partial view, do
9177 -- not generate an overflow on the discriminant expression. The
9178 -- check will be generated when constraining the full view.
9180 if Is_Private_Type (T)
9181 and then Present (Full_View (T))
9183 Analyze_And_Resolve (Expr, BDT, Suppress => Overflow_Check);
9185 Analyze_And_Resolve (Expr, BDT);
9187 end Process_Discriminant_Expression;
9189 -- Declarations local to Build_Discriminant_Constraints
9193 Elist : constant Elist_Id := New_Elmt_List;
9201 Discrim_Present : Boolean := False;
9203 -- Start of processing for Build_Discriminant_Constraints
9206 -- The following loop will process positional associations only.
9207 -- For a positional association, the (single) discriminant is
9208 -- implicitly specified by position, in textual order (RM 3.7.2).
9210 Discr := First_Discriminant (T);
9211 Constr := First (Constraints (C));
9212 for D in Discr_Expr'Range loop
9213 exit when Nkind (Constr) = N_Discriminant_Association;
9216 Error_Msg_N ("too few discriminants given in constraint", C);
9217 return New_Elmt_List;
9219 elsif Nkind (Constr) = N_Range
9220 or else (Nkind (Constr) = N_Attribute_Reference
9221 and then Attribute_Name (Constr) = Name_Range)
9224 ("a range is not a valid discriminant constraint", Constr);
9225 Discr_Expr (D) := Error;
9228 Process_Discriminant_Expression (Constr, Discr);
9229 Discr_Expr (D) := Constr;
9232 Next_Discriminant (Discr);
9236 if No (Discr) and then Present (Constr) then
9237 Error_Msg_N ("too many discriminants given in constraint", Constr);
9238 return New_Elmt_List;
9241 -- Named associations can be given in any order, but if both positional
9242 -- and named associations are used in the same discriminant constraint,
9243 -- then positional associations must occur first, at their normal
9244 -- position. Hence once a named association is used, the rest of the
9245 -- discriminant constraint must use only named associations.
9247 while Present (Constr) loop
9249 -- Positional association forbidden after a named association
9251 if Nkind (Constr) /= N_Discriminant_Association then
9252 Error_Msg_N ("positional association follows named one", Constr);
9253 return New_Elmt_List;
9255 -- Otherwise it is a named association
9258 -- E records the type of the discriminants in the named
9259 -- association. All the discriminants specified in the same name
9260 -- association must have the same type.
9264 -- Search the list of discriminants in T to see if the simple name
9265 -- given in the constraint matches any of them.
9267 Id := First (Selector_Names (Constr));
9268 while Present (Id) loop
9271 -- If Original_Discriminant is present, we are processing a
9272 -- generic instantiation and this is an instance node. We need
9273 -- to find the name of the corresponding discriminant in the
9274 -- actual record type T and not the name of the discriminant in
9275 -- the generic formal. Example:
9278 -- type G (D : int) is private;
9280 -- subtype W is G (D => 1);
9282 -- type Rec (X : int) is record ... end record;
9283 -- package Q is new P (G => Rec);
9285 -- At the point of the instantiation, formal type G is Rec
9286 -- and therefore when reanalyzing "subtype W is G (D => 1);"
9287 -- which really looks like "subtype W is Rec (D => 1);" at
9288 -- the point of instantiation, we want to find the discriminant
9289 -- that corresponds to D in Rec, i.e. X.
9291 if Present (Original_Discriminant (Id))
9292 and then In_Instance
9294 Discr := Find_Corresponding_Discriminant (Id, T);
9298 Discr := First_Discriminant (T);
9299 while Present (Discr) loop
9300 if Chars (Discr) = Chars (Id) then
9305 Next_Discriminant (Discr);
9309 Error_Msg_N ("& does not match any discriminant", Id);
9310 return New_Elmt_List;
9312 -- If the parent type is a generic formal, preserve the
9313 -- name of the discriminant for subsequent instances.
9314 -- see comment at the beginning of this if statement.
9316 elsif Is_Generic_Type (Root_Type (T)) then
9317 Set_Original_Discriminant (Id, Discr);
9321 Position := Pos_Of_Discr (T, Discr);
9323 if Present (Discr_Expr (Position)) then
9324 Error_Msg_N ("duplicate constraint for discriminant&", Id);
9327 -- Each discriminant specified in the same named association
9328 -- must be associated with a separate copy of the
9329 -- corresponding expression.
9331 if Present (Next (Id)) then
9332 Expr := New_Copy_Tree (Expression (Constr));
9333 Set_Parent (Expr, Parent (Expression (Constr)));
9335 Expr := Expression (Constr);
9338 Discr_Expr (Position) := Expr;
9339 Process_Discriminant_Expression (Expr, Discr);
9342 -- A discriminant association with more than one discriminant
9343 -- name is only allowed if the named discriminants are all of
9344 -- the same type (RM 3.7.1(8)).
9347 E := Base_Type (Etype (Discr));
9349 elsif Base_Type (Etype (Discr)) /= E then
9351 ("all discriminants in an association " &
9352 "must have the same type", Id);
9362 -- A discriminant constraint must provide exactly one value for each
9363 -- discriminant of the type (RM 3.7.1(8)).
9365 for J in Discr_Expr'Range loop
9366 if No (Discr_Expr (J)) then
9367 Error_Msg_N ("too few discriminants given in constraint", C);
9368 return New_Elmt_List;
9372 -- Determine if there are discriminant expressions in the constraint
9374 for J in Discr_Expr'Range loop
9375 if Denotes_Discriminant
9376 (Discr_Expr (J), Check_Concurrent => True)
9378 Discrim_Present := True;
9382 -- Build an element list consisting of the expressions given in the
9383 -- discriminant constraint and apply the appropriate checks. The list
9384 -- is constructed after resolving any named discriminant associations
9385 -- and therefore the expressions appear in the textual order of the
9388 Discr := First_Discriminant (T);
9389 for J in Discr_Expr'Range loop
9390 if Discr_Expr (J) /= Error then
9391 Append_Elmt (Discr_Expr (J), Elist);
9393 -- If any of the discriminant constraints is given by a
9394 -- discriminant and we are in a derived type declaration we
9395 -- have a discriminant renaming. Establish link between new
9396 -- and old discriminant.
9398 if Denotes_Discriminant (Discr_Expr (J)) then
9400 Set_Corresponding_Discriminant
9401 (Entity (Discr_Expr (J)), Discr);
9404 -- Force the evaluation of non-discriminant expressions.
9405 -- If we have found a discriminant in the constraint 3.4(26)
9406 -- and 3.8(18) demand that no range checks are performed are
9407 -- after evaluation. If the constraint is for a component
9408 -- definition that has a per-object constraint, expressions are
9409 -- evaluated but not checked either. In all other cases perform
9413 if Discrim_Present then
9416 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
9418 Has_Per_Object_Constraint
9419 (Defining_Identifier (Parent (Parent (Def))))
9423 elsif Is_Access_Type (Etype (Discr)) then
9424 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
9427 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
9430 Force_Evaluation (Discr_Expr (J));
9433 -- Check that the designated type of an access discriminant's
9434 -- expression is not a class-wide type unless the discriminant's
9435 -- designated type is also class-wide.
9437 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
9438 and then not Is_Class_Wide_Type
9439 (Designated_Type (Etype (Discr)))
9440 and then Etype (Discr_Expr (J)) /= Any_Type
9441 and then Is_Class_Wide_Type
9442 (Designated_Type (Etype (Discr_Expr (J))))
9444 Wrong_Type (Discr_Expr (J), Etype (Discr));
9446 elsif Is_Access_Type (Etype (Discr))
9447 and then not Is_Access_Constant (Etype (Discr))
9448 and then Is_Access_Type (Etype (Discr_Expr (J)))
9449 and then Is_Access_Constant (Etype (Discr_Expr (J)))
9452 ("constraint for discriminant& must be access to variable",
9457 Next_Discriminant (Discr);
9461 end Build_Discriminant_Constraints;
9463 ---------------------------------
9464 -- Build_Discriminated_Subtype --
9465 ---------------------------------
9467 procedure Build_Discriminated_Subtype
9471 Related_Nod : Node_Id;
9472 For_Access : Boolean := False)
9474 Has_Discrs : constant Boolean := Has_Discriminants (T);
9475 Constrained : constant Boolean :=
9477 and then not Is_Empty_Elmt_List (Elist)
9478 and then not Is_Class_Wide_Type (T))
9479 or else Is_Constrained (T);
9482 if Ekind (T) = E_Record_Type then
9484 Set_Ekind (Def_Id, E_Private_Subtype);
9485 Set_Is_For_Access_Subtype (Def_Id, True);
9487 Set_Ekind (Def_Id, E_Record_Subtype);
9490 -- Inherit preelaboration flag from base, for types for which it
9491 -- may have been set: records, private types, protected types.
9493 Set_Known_To_Have_Preelab_Init
9494 (Def_Id, Known_To_Have_Preelab_Init (T));
9496 elsif Ekind (T) = E_Task_Type then
9497 Set_Ekind (Def_Id, E_Task_Subtype);
9499 elsif Ekind (T) = E_Protected_Type then
9500 Set_Ekind (Def_Id, E_Protected_Subtype);
9501 Set_Known_To_Have_Preelab_Init
9502 (Def_Id, Known_To_Have_Preelab_Init (T));
9504 elsif Is_Private_Type (T) then
9505 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
9506 Set_Known_To_Have_Preelab_Init
9507 (Def_Id, Known_To_Have_Preelab_Init (T));
9509 -- Private subtypes may have private dependents
9511 Set_Private_Dependents (Def_Id, New_Elmt_List);
9513 elsif Is_Class_Wide_Type (T) then
9514 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
9517 -- Incomplete type. Attach subtype to list of dependents, to be
9518 -- completed with full view of parent type, unless is it the
9519 -- designated subtype of a record component within an init_proc.
9520 -- This last case arises for a component of an access type whose
9521 -- designated type is incomplete (e.g. a Taft Amendment type).
9522 -- The designated subtype is within an inner scope, and needs no
9523 -- elaboration, because only the access type is needed in the
9524 -- initialization procedure.
9526 Set_Ekind (Def_Id, Ekind (T));
9528 if For_Access and then Within_Init_Proc then
9531 Append_Elmt (Def_Id, Private_Dependents (T));
9535 Set_Etype (Def_Id, T);
9536 Init_Size_Align (Def_Id);
9537 Set_Has_Discriminants (Def_Id, Has_Discrs);
9538 Set_Is_Constrained (Def_Id, Constrained);
9540 Set_First_Entity (Def_Id, First_Entity (T));
9541 Set_Last_Entity (Def_Id, Last_Entity (T));
9542 Set_Has_Implicit_Dereference
9543 (Def_Id, Has_Implicit_Dereference (T));
9545 -- If the subtype is the completion of a private declaration, there may
9546 -- have been representation clauses for the partial view, and they must
9547 -- be preserved. Build_Derived_Type chains the inherited clauses with
9548 -- the ones appearing on the extension. If this comes from a subtype
9549 -- declaration, all clauses are inherited.
9551 if No (First_Rep_Item (Def_Id)) then
9552 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
9555 if Is_Tagged_Type (T) then
9556 Set_Is_Tagged_Type (Def_Id);
9557 Set_No_Tagged_Streams_Pragma (Def_Id, No_Tagged_Streams_Pragma (T));
9558 Make_Class_Wide_Type (Def_Id);
9561 Set_Stored_Constraint (Def_Id, No_Elist);
9564 Set_Discriminant_Constraint (Def_Id, Elist);
9565 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
9568 if Is_Tagged_Type (T) then
9570 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
9571 -- concurrent record type (which has the list of primitive
9574 if Ada_Version >= Ada_2005
9575 and then Is_Concurrent_Type (T)
9577 Set_Corresponding_Record_Type (Def_Id,
9578 Corresponding_Record_Type (T));
9580 Set_Direct_Primitive_Operations (Def_Id,
9581 Direct_Primitive_Operations (T));
9584 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
9587 -- Subtypes introduced by component declarations do not need to be
9588 -- marked as delayed, and do not get freeze nodes, because the semantics
9589 -- verifies that the parents of the subtypes are frozen before the
9590 -- enclosing record is frozen.
9592 if not Is_Type (Scope (Def_Id)) then
9593 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
9595 if Is_Private_Type (T)
9596 and then Present (Full_View (T))
9598 Conditional_Delay (Def_Id, Full_View (T));
9600 Conditional_Delay (Def_Id, T);
9604 if Is_Record_Type (T) then
9605 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
9608 and then not Is_Empty_Elmt_List (Elist)
9609 and then not For_Access
9611 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
9612 elsif not For_Access then
9613 Set_Cloned_Subtype (Def_Id, T);
9616 end Build_Discriminated_Subtype;
9618 ---------------------------
9619 -- Build_Itype_Reference --
9620 ---------------------------
9622 procedure Build_Itype_Reference
9626 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
9629 -- Itype references are only created for use by the back-end
9631 if Inside_A_Generic then
9634 Set_Itype (IR, Ityp);
9635 Insert_After (Nod, IR);
9637 end Build_Itype_Reference;
9639 ------------------------
9640 -- Build_Scalar_Bound --
9641 ------------------------
9643 function Build_Scalar_Bound
9646 Der_T : Entity_Id) return Node_Id
9648 New_Bound : Entity_Id;
9651 -- Note: not clear why this is needed, how can the original bound
9652 -- be unanalyzed at this point? and if it is, what business do we
9653 -- have messing around with it? and why is the base type of the
9654 -- parent type the right type for the resolution. It probably is
9655 -- not. It is OK for the new bound we are creating, but not for
9656 -- the old one??? Still if it never happens, no problem.
9658 Analyze_And_Resolve (Bound, Base_Type (Par_T));
9660 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
9661 New_Bound := New_Copy (Bound);
9662 Set_Etype (New_Bound, Der_T);
9663 Set_Analyzed (New_Bound);
9665 elsif Is_Entity_Name (Bound) then
9666 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
9668 -- The following is almost certainly wrong. What business do we have
9669 -- relocating a node (Bound) that is presumably still attached to
9670 -- the tree elsewhere???
9673 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
9676 Set_Etype (New_Bound, Der_T);
9678 end Build_Scalar_Bound;
9680 --------------------------------
9681 -- Build_Underlying_Full_View --
9682 --------------------------------
9684 procedure Build_Underlying_Full_View
9689 Loc : constant Source_Ptr := Sloc (N);
9690 Subt : constant Entity_Id :=
9691 Make_Defining_Identifier
9692 (Loc, New_External_Name (Chars (Typ), 'S'));
9699 procedure Set_Discriminant_Name (Id : Node_Id);
9700 -- If the derived type has discriminants, they may rename discriminants
9701 -- of the parent. When building the full view of the parent, we need to
9702 -- recover the names of the original discriminants if the constraint is
9703 -- given by named associations.
9705 ---------------------------
9706 -- Set_Discriminant_Name --
9707 ---------------------------
9709 procedure Set_Discriminant_Name (Id : Node_Id) is
9713 Set_Original_Discriminant (Id, Empty);
9715 if Has_Discriminants (Typ) then
9716 Disc := First_Discriminant (Typ);
9717 while Present (Disc) loop
9718 if Chars (Disc) = Chars (Id)
9719 and then Present (Corresponding_Discriminant (Disc))
9721 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
9723 Next_Discriminant (Disc);
9726 end Set_Discriminant_Name;
9728 -- Start of processing for Build_Underlying_Full_View
9731 if Nkind (N) = N_Full_Type_Declaration then
9732 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
9734 elsif Nkind (N) = N_Subtype_Declaration then
9735 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
9737 elsif Nkind (N) = N_Component_Declaration then
9740 (Constraint (Subtype_Indication (Component_Definition (N))));
9743 raise Program_Error;
9746 C := First (Constraints (Constr));
9747 while Present (C) loop
9748 if Nkind (C) = N_Discriminant_Association then
9749 Id := First (Selector_Names (C));
9750 while Present (Id) loop
9751 Set_Discriminant_Name (Id);
9760 Make_Subtype_Declaration (Loc,
9761 Defining_Identifier => Subt,
9762 Subtype_Indication =>
9763 Make_Subtype_Indication (Loc,
9764 Subtype_Mark => New_Occurrence_Of (Par, Loc),
9765 Constraint => New_Copy_Tree (Constr)));
9767 -- If this is a component subtype for an outer itype, it is not
9768 -- a list member, so simply set the parent link for analysis: if
9769 -- the enclosing type does not need to be in a declarative list,
9770 -- neither do the components.
9772 if Is_List_Member (N)
9773 and then Nkind (N) /= N_Component_Declaration
9775 Insert_Before (N, Indic);
9777 Set_Parent (Indic, Parent (N));
9781 Set_Underlying_Full_View (Typ, Full_View (Subt));
9782 end Build_Underlying_Full_View;
9784 -------------------------------
9785 -- Check_Abstract_Overriding --
9786 -------------------------------
9788 procedure Check_Abstract_Overriding (T : Entity_Id) is
9789 Alias_Subp : Entity_Id;
9795 procedure Check_Pragma_Implemented (Subp : Entity_Id);
9796 -- Ada 2012 (AI05-0030): Subprogram Subp overrides an interface routine
9797 -- which has pragma Implemented already set. Check whether Subp's entity
9798 -- kind conforms to the implementation kind of the overridden routine.
9800 procedure Check_Pragma_Implemented
9802 Iface_Subp : Entity_Id);
9803 -- Ada 2012 (AI05-0030): Subprogram Subp overrides interface routine
9804 -- Iface_Subp and both entities have pragma Implemented already set on
9805 -- them. Check whether the two implementation kinds are conforming.
9807 procedure Inherit_Pragma_Implemented
9809 Iface_Subp : Entity_Id);
9810 -- Ada 2012 (AI05-0030): Interface primitive Subp overrides interface
9811 -- subprogram Iface_Subp which has been marked by pragma Implemented.
9812 -- Propagate the implementation kind of Iface_Subp to Subp.
9814 ------------------------------
9815 -- Check_Pragma_Implemented --
9816 ------------------------------
9818 procedure Check_Pragma_Implemented (Subp : Entity_Id) is
9819 Iface_Alias : constant Entity_Id := Interface_Alias (Subp);
9820 Impl_Kind : constant Name_Id := Implementation_Kind (Iface_Alias);
9821 Subp_Alias : constant Entity_Id := Alias (Subp);
9822 Contr_Typ : Entity_Id;
9823 Impl_Subp : Entity_Id;
9826 -- Subp must have an alias since it is a hidden entity used to link
9827 -- an interface subprogram to its overriding counterpart.
9829 pragma Assert (Present (Subp_Alias));
9831 -- Handle aliases to synchronized wrappers
9833 Impl_Subp := Subp_Alias;
9835 if Is_Primitive_Wrapper (Impl_Subp) then
9836 Impl_Subp := Wrapped_Entity (Impl_Subp);
9839 -- Extract the type of the controlling formal
9841 Contr_Typ := Etype (First_Formal (Subp_Alias));
9843 if Is_Concurrent_Record_Type (Contr_Typ) then
9844 Contr_Typ := Corresponding_Concurrent_Type (Contr_Typ);
9847 -- An interface subprogram whose implementation kind is By_Entry must
9848 -- be implemented by an entry.
9850 if Impl_Kind = Name_By_Entry
9851 and then Ekind (Impl_Subp) /= E_Entry
9853 Error_Msg_Node_2 := Iface_Alias;
9855 ("type & must implement abstract subprogram & with an entry",
9856 Subp_Alias, Contr_Typ);
9858 elsif Impl_Kind = Name_By_Protected_Procedure then
9860 -- An interface subprogram whose implementation kind is By_
9861 -- Protected_Procedure cannot be implemented by a primitive
9862 -- procedure of a task type.
9864 if Ekind (Contr_Typ) /= E_Protected_Type then
9865 Error_Msg_Node_2 := Contr_Typ;
9867 ("interface subprogram & cannot be implemented by a " &
9868 "primitive procedure of task type &", Subp_Alias,
9871 -- An interface subprogram whose implementation kind is By_
9872 -- Protected_Procedure must be implemented by a procedure.
9874 elsif Ekind (Impl_Subp) /= E_Procedure then
9875 Error_Msg_Node_2 := Iface_Alias;
9877 ("type & must implement abstract subprogram & with a " &
9878 "procedure", Subp_Alias, Contr_Typ);
9880 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
9881 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
9883 Error_Msg_Name_1 := Impl_Kind;
9885 ("overriding operation& must have synchronization%",
9889 -- If primitive has Optional synchronization, overriding operation
9890 -- must match if it has an explicit synchronization..
9892 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
9893 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
9895 Error_Msg_Name_1 := Impl_Kind;
9897 ("overriding operation& must have syncrhonization%",
9900 end Check_Pragma_Implemented;
9902 ------------------------------
9903 -- Check_Pragma_Implemented --
9904 ------------------------------
9906 procedure Check_Pragma_Implemented
9908 Iface_Subp : Entity_Id)
9910 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
9911 Subp_Kind : constant Name_Id := Implementation_Kind (Subp);
9914 -- Ada 2012 (AI05-0030): The implementation kinds of an overridden
9915 -- and overriding subprogram are different. In general this is an
9916 -- error except when the implementation kind of the overridden
9917 -- subprograms is By_Any or Optional.
9919 if Iface_Kind /= Subp_Kind
9920 and then Iface_Kind /= Name_By_Any
9921 and then Iface_Kind /= Name_Optional
9923 if Iface_Kind = Name_By_Entry then
9925 ("incompatible implementation kind, overridden subprogram " &
9926 "is marked By_Entry", Subp);
9929 ("incompatible implementation kind, overridden subprogram " &
9930 "is marked By_Protected_Procedure", Subp);
9933 end Check_Pragma_Implemented;
9935 --------------------------------
9936 -- Inherit_Pragma_Implemented --
9937 --------------------------------
9939 procedure Inherit_Pragma_Implemented
9941 Iface_Subp : Entity_Id)
9943 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
9944 Loc : constant Source_Ptr := Sloc (Subp);
9945 Impl_Prag : Node_Id;
9948 -- Since the implementation kind is stored as a representation item
9949 -- rather than a flag, create a pragma node.
9953 Chars => Name_Implemented,
9954 Pragma_Argument_Associations => New_List (
9955 Make_Pragma_Argument_Association (Loc,
9956 Expression => New_Occurrence_Of (Subp, Loc)),
9958 Make_Pragma_Argument_Association (Loc,
9959 Expression => Make_Identifier (Loc, Iface_Kind))));
9961 -- The pragma doesn't need to be analyzed because it is internally
9962 -- built. It is safe to directly register it as a rep item since we
9963 -- are only interested in the characters of the implementation kind.
9965 Record_Rep_Item (Subp, Impl_Prag);
9966 end Inherit_Pragma_Implemented;
9968 -- Start of processing for Check_Abstract_Overriding
9971 Op_List := Primitive_Operations (T);
9973 -- Loop to check primitive operations
9975 Elmt := First_Elmt (Op_List);
9976 while Present (Elmt) loop
9977 Subp := Node (Elmt);
9978 Alias_Subp := Alias (Subp);
9980 -- Inherited subprograms are identified by the fact that they do not
9981 -- come from source, and the associated source location is the
9982 -- location of the first subtype of the derived type.
9984 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
9985 -- subprograms that "require overriding".
9987 -- Special exception, do not complain about failure to override the
9988 -- stream routines _Input and _Output, as well as the primitive
9989 -- operations used in dispatching selects since we always provide
9990 -- automatic overridings for these subprograms.
9992 -- The partial view of T may have been a private extension, for
9993 -- which inherited functions dispatching on result are abstract.
9994 -- If the full view is a null extension, there is no need for
9995 -- overriding in Ada 2005, but wrappers need to be built for them
9996 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
9998 if Is_Null_Extension (T)
9999 and then Has_Controlling_Result (Subp)
10000 and then Ada_Version >= Ada_2005
10001 and then Present (Alias_Subp)
10002 and then not Comes_From_Source (Subp)
10003 and then not Is_Abstract_Subprogram (Alias_Subp)
10004 and then not Is_Access_Type (Etype (Subp))
10008 -- Ada 2005 (AI-251): Internal entities of interfaces need no
10009 -- processing because this check is done with the aliased
10012 elsif Present (Interface_Alias (Subp)) then
10015 elsif (Is_Abstract_Subprogram (Subp)
10016 or else Requires_Overriding (Subp)
10018 (Has_Controlling_Result (Subp)
10019 and then Present (Alias_Subp)
10020 and then not Comes_From_Source (Subp)
10021 and then Sloc (Subp) = Sloc (First_Subtype (T))))
10022 and then not Is_TSS (Subp, TSS_Stream_Input)
10023 and then not Is_TSS (Subp, TSS_Stream_Output)
10024 and then not Is_Abstract_Type (T)
10025 and then not Is_Predefined_Interface_Primitive (Subp)
10027 -- Ada 2005 (AI-251): Do not consider hidden entities associated
10028 -- with abstract interface types because the check will be done
10029 -- with the aliased entity (otherwise we generate a duplicated
10032 and then not Present (Interface_Alias (Subp))
10034 if Present (Alias_Subp) then
10036 -- Only perform the check for a derived subprogram when the
10037 -- type has an explicit record extension. This avoids incorrect
10038 -- flagging of abstract subprograms for the case of a type
10039 -- without an extension that is derived from a formal type
10040 -- with a tagged actual (can occur within a private part).
10042 -- Ada 2005 (AI-391): In the case of an inherited function with
10043 -- a controlling result of the type, the rule does not apply if
10044 -- the type is a null extension (unless the parent function
10045 -- itself is abstract, in which case the function must still be
10046 -- be overridden). The expander will generate an overriding
10047 -- wrapper function calling the parent subprogram (see
10048 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
10050 Type_Def := Type_Definition (Parent (T));
10052 if Nkind (Type_Def) = N_Derived_Type_Definition
10053 and then Present (Record_Extension_Part (Type_Def))
10055 (Ada_Version < Ada_2005
10056 or else not Is_Null_Extension (T)
10057 or else Ekind (Subp) = E_Procedure
10058 or else not Has_Controlling_Result (Subp)
10059 or else Is_Abstract_Subprogram (Alias_Subp)
10060 or else Requires_Overriding (Subp)
10061 or else Is_Access_Type (Etype (Subp)))
10063 -- Avoid reporting error in case of abstract predefined
10064 -- primitive inherited from interface type because the
10065 -- body of internally generated predefined primitives
10066 -- of tagged types are generated later by Freeze_Type
10068 if Is_Interface (Root_Type (T))
10069 and then Is_Abstract_Subprogram (Subp)
10070 and then Is_Predefined_Dispatching_Operation (Subp)
10071 and then not Comes_From_Source (Ultimate_Alias (Subp))
10075 -- A null extension is not obliged to override an inherited
10076 -- procedure subject to pragma Extensions_Visible with value
10077 -- False and at least one controlling OUT parameter
10078 -- (SPARK RM 6.1.7(6)).
10080 elsif Is_Null_Extension (T)
10081 and then Is_EVF_Procedure (Subp)
10087 ("type must be declared abstract or & overridden",
10090 -- Traverse the whole chain of aliased subprograms to
10091 -- complete the error notification. This is especially
10092 -- useful for traceability of the chain of entities when
10093 -- the subprogram corresponds with an interface
10094 -- subprogram (which may be defined in another package).
10096 if Present (Alias_Subp) then
10102 while Present (Alias (E)) loop
10104 -- Avoid reporting redundant errors on entities
10105 -- inherited from interfaces
10107 if Sloc (E) /= Sloc (T) then
10108 Error_Msg_Sloc := Sloc (E);
10110 ("\& has been inherited #", T, Subp);
10116 Error_Msg_Sloc := Sloc (E);
10118 -- AI05-0068: report if there is an overriding
10119 -- non-abstract subprogram that is invisible.
10122 and then not Is_Abstract_Subprogram (E)
10125 ("\& subprogram# is not visible",
10128 -- Clarify the case where a non-null extension must
10129 -- override inherited procedure subject to pragma
10130 -- Extensions_Visible with value False and at least
10131 -- one controlling OUT param.
10133 elsif Is_EVF_Procedure (E) then
10135 ("\& # is subject to Extensions_Visible False",
10140 ("\& has been inherited from subprogram #",
10147 -- Ada 2005 (AI-345): Protected or task type implementing
10148 -- abstract interfaces.
10150 elsif Is_Concurrent_Record_Type (T)
10151 and then Present (Interfaces (T))
10153 -- There is no need to check here RM 9.4(11.9/3) since we
10154 -- are processing the corresponding record type and the
10155 -- mode of the overriding subprograms was verified by
10156 -- Check_Conformance when the corresponding concurrent
10157 -- type declaration was analyzed.
10160 ("interface subprogram & must be overridden", T, Subp);
10162 -- Examine primitive operations of synchronized type to find
10163 -- homonyms that have the wrong profile.
10169 Prim := First_Entity (Corresponding_Concurrent_Type (T));
10170 while Present (Prim) loop
10171 if Chars (Prim) = Chars (Subp) then
10173 ("profile is not type conformant with prefixed "
10174 & "view profile of inherited operation&",
10178 Next_Entity (Prim);
10184 Error_Msg_Node_2 := T;
10186 ("abstract subprogram& not allowed for type&", Subp);
10188 -- Also post unconditional warning on the type (unconditional
10189 -- so that if there are more than one of these cases, we get
10190 -- them all, and not just the first one).
10192 Error_Msg_Node_2 := Subp;
10193 Error_Msg_N ("nonabstract type& has abstract subprogram&!", T);
10196 -- A subprogram subject to pragma Extensions_Visible with value
10197 -- "True" cannot override a subprogram subject to the same pragma
10198 -- with value "False" (SPARK RM 6.1.7(5)).
10200 elsif Extensions_Visible_Status (Subp) = Extensions_Visible_True
10201 and then Present (Overridden_Operation (Subp))
10202 and then Extensions_Visible_Status (Overridden_Operation (Subp)) =
10203 Extensions_Visible_False
10205 Error_Msg_Sloc := Sloc (Overridden_Operation (Subp));
10207 ("subprogram & with Extensions_Visible True cannot override "
10208 & "subprogram # with Extensions_Visible False", Subp);
10211 -- Ada 2012 (AI05-0030): Perform checks related to pragma Implemented
10213 -- Subp is an expander-generated procedure which maps an interface
10214 -- alias to a protected wrapper. The interface alias is flagged by
10215 -- pragma Implemented. Ensure that Subp is a procedure when the
10216 -- implementation kind is By_Protected_Procedure or an entry when
10219 if Ada_Version >= Ada_2012
10220 and then Is_Hidden (Subp)
10221 and then Present (Interface_Alias (Subp))
10222 and then Has_Rep_Pragma (Interface_Alias (Subp), Name_Implemented)
10224 Check_Pragma_Implemented (Subp);
10227 -- Subp is an interface primitive which overrides another interface
10228 -- primitive marked with pragma Implemented.
10230 if Ada_Version >= Ada_2012
10231 and then Present (Overridden_Operation (Subp))
10232 and then Has_Rep_Pragma
10233 (Overridden_Operation (Subp), Name_Implemented)
10235 -- If the overriding routine is also marked by Implemented, check
10236 -- that the two implementation kinds are conforming.
10238 if Has_Rep_Pragma (Subp, Name_Implemented) then
10239 Check_Pragma_Implemented
10241 Iface_Subp => Overridden_Operation (Subp));
10243 -- Otherwise the overriding routine inherits the implementation
10244 -- kind from the overridden subprogram.
10247 Inherit_Pragma_Implemented
10249 Iface_Subp => Overridden_Operation (Subp));
10253 -- If the operation is a wrapper for a synchronized primitive, it
10254 -- may be called indirectly through a dispatching select. We assume
10255 -- that it will be referenced elsewhere indirectly, and suppress
10256 -- warnings about an unused entity.
10258 if Is_Primitive_Wrapper (Subp)
10259 and then Present (Wrapped_Entity (Subp))
10261 Set_Referenced (Wrapped_Entity (Subp));
10266 end Check_Abstract_Overriding;
10268 ------------------------------------------------
10269 -- Check_Access_Discriminant_Requires_Limited --
10270 ------------------------------------------------
10272 procedure Check_Access_Discriminant_Requires_Limited
10277 -- A discriminant_specification for an access discriminant shall appear
10278 -- only in the declaration for a task or protected type, or for a type
10279 -- with the reserved word 'limited' in its definition or in one of its
10280 -- ancestors (RM 3.7(10)).
10282 -- AI-0063: The proper condition is that type must be immutably limited,
10283 -- or else be a partial view.
10285 if Nkind (Discriminant_Type (D)) = N_Access_Definition then
10286 if Is_Limited_View (Current_Scope)
10288 (Nkind (Parent (Current_Scope)) = N_Private_Type_Declaration
10289 and then Limited_Present (Parent (Current_Scope)))
10295 ("access discriminants allowed only for limited types", Loc);
10298 end Check_Access_Discriminant_Requires_Limited;
10300 -----------------------------------
10301 -- Check_Aliased_Component_Types --
10302 -----------------------------------
10304 procedure Check_Aliased_Component_Types (T : Entity_Id) is
10308 -- ??? Also need to check components of record extensions, but not
10309 -- components of protected types (which are always limited).
10311 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
10312 -- types to be unconstrained. This is safe because it is illegal to
10313 -- create access subtypes to such types with explicit discriminant
10316 if not Is_Limited_Type (T) then
10317 if Ekind (T) = E_Record_Type then
10318 C := First_Component (T);
10319 while Present (C) loop
10321 and then Has_Discriminants (Etype (C))
10322 and then not Is_Constrained (Etype (C))
10323 and then not In_Instance_Body
10324 and then Ada_Version < Ada_2005
10327 ("aliased component must be constrained (RM 3.6(11))",
10331 Next_Component (C);
10334 elsif Ekind (T) = E_Array_Type then
10335 if Has_Aliased_Components (T)
10336 and then Has_Discriminants (Component_Type (T))
10337 and then not Is_Constrained (Component_Type (T))
10338 and then not In_Instance_Body
10339 and then Ada_Version < Ada_2005
10342 ("aliased component type must be constrained (RM 3.6(11))",
10347 end Check_Aliased_Component_Types;
10349 ---------------------------------------
10350 -- Check_Anonymous_Access_Components --
10351 ---------------------------------------
10353 procedure Check_Anonymous_Access_Components
10354 (Typ_Decl : Node_Id;
10357 Comp_List : Node_Id)
10359 Loc : constant Source_Ptr := Sloc (Typ_Decl);
10360 Anon_Access : Entity_Id;
10363 Comp_Def : Node_Id;
10365 Type_Def : Node_Id;
10367 procedure Build_Incomplete_Type_Declaration;
10368 -- If the record type contains components that include an access to the
10369 -- current record, then create an incomplete type declaration for the
10370 -- record, to be used as the designated type of the anonymous access.
10371 -- This is done only once, and only if there is no previous partial
10372 -- view of the type.
10374 function Designates_T (Subt : Node_Id) return Boolean;
10375 -- Check whether a node designates the enclosing record type, or 'Class
10378 function Mentions_T (Acc_Def : Node_Id) return Boolean;
10379 -- Check whether an access definition includes a reference to
10380 -- the enclosing record type. The reference can be a subtype mark
10381 -- in the access definition itself, a 'Class attribute reference, or
10382 -- recursively a reference appearing in a parameter specification
10383 -- or result definition of an access_to_subprogram definition.
10385 --------------------------------------
10386 -- Build_Incomplete_Type_Declaration --
10387 --------------------------------------
10389 procedure Build_Incomplete_Type_Declaration is
10394 -- Is_Tagged indicates whether the type is tagged. It is tagged if
10395 -- it's "is new ... with record" or else "is tagged record ...".
10397 Is_Tagged : constant Boolean :=
10398 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
10400 Present (Record_Extension_Part (Type_Definition (Typ_Decl))))
10402 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
10403 and then Tagged_Present (Type_Definition (Typ_Decl)));
10406 -- If there is a previous partial view, no need to create a new one
10407 -- If the partial view, given by Prev, is incomplete, If Prev is
10408 -- a private declaration, full declaration is flagged accordingly.
10410 if Prev /= Typ then
10412 Make_Class_Wide_Type (Prev);
10413 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
10414 Set_Etype (Class_Wide_Type (Typ), Typ);
10419 elsif Has_Private_Declaration (Typ) then
10421 -- If we refer to T'Class inside T, and T is the completion of a
10422 -- private type, then make sure the class-wide type exists.
10425 Make_Class_Wide_Type (Typ);
10430 -- If there was a previous anonymous access type, the incomplete
10431 -- type declaration will have been created already.
10433 elsif Present (Current_Entity (Typ))
10434 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
10435 and then Full_View (Current_Entity (Typ)) = Typ
10438 and then Comes_From_Source (Current_Entity (Typ))
10439 and then not Is_Tagged_Type (Current_Entity (Typ))
10441 Make_Class_Wide_Type (Typ);
10443 ("incomplete view of tagged type should be declared tagged??",
10444 Parent (Current_Entity (Typ)));
10449 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
10450 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
10452 -- Type has already been inserted into the current scope. Remove
10453 -- it, and add incomplete declaration for type, so that subsequent
10454 -- anonymous access types can use it. The entity is unchained from
10455 -- the homonym list and from immediate visibility. After analysis,
10456 -- the entity in the incomplete declaration becomes immediately
10457 -- visible in the record declaration that follows.
10459 H := Current_Entity (Typ);
10462 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
10465 and then Homonym (H) /= Typ
10467 H := Homonym (Typ);
10470 Set_Homonym (H, Homonym (Typ));
10473 Insert_Before (Typ_Decl, Decl);
10475 Set_Full_View (Inc_T, Typ);
10479 -- Create a common class-wide type for both views, and set the
10480 -- Etype of the class-wide type to the full view.
10482 Make_Class_Wide_Type (Inc_T);
10483 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
10484 Set_Etype (Class_Wide_Type (Typ), Typ);
10487 end Build_Incomplete_Type_Declaration;
10493 function Designates_T (Subt : Node_Id) return Boolean is
10494 Type_Id : constant Name_Id := Chars (Typ);
10496 function Names_T (Nam : Node_Id) return Boolean;
10497 -- The record type has not been introduced in the current scope
10498 -- yet, so we must examine the name of the type itself, either
10499 -- an identifier T, or an expanded name of the form P.T, where
10500 -- P denotes the current scope.
10506 function Names_T (Nam : Node_Id) return Boolean is
10508 if Nkind (Nam) = N_Identifier then
10509 return Chars (Nam) = Type_Id;
10511 elsif Nkind (Nam) = N_Selected_Component then
10512 if Chars (Selector_Name (Nam)) = Type_Id then
10513 if Nkind (Prefix (Nam)) = N_Identifier then
10514 return Chars (Prefix (Nam)) = Chars (Current_Scope);
10516 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
10517 return Chars (Selector_Name (Prefix (Nam))) =
10518 Chars (Current_Scope);
10532 -- Start of processing for Designates_T
10535 if Nkind (Subt) = N_Identifier then
10536 return Chars (Subt) = Type_Id;
10538 -- Reference can be through an expanded name which has not been
10539 -- analyzed yet, and which designates enclosing scopes.
10541 elsif Nkind (Subt) = N_Selected_Component then
10542 if Names_T (Subt) then
10545 -- Otherwise it must denote an entity that is already visible.
10546 -- The access definition may name a subtype of the enclosing
10547 -- type, if there is a previous incomplete declaration for it.
10550 Find_Selected_Component (Subt);
10552 Is_Entity_Name (Subt)
10553 and then Scope (Entity (Subt)) = Current_Scope
10555 (Chars (Base_Type (Entity (Subt))) = Type_Id
10557 (Is_Class_Wide_Type (Entity (Subt))
10559 Chars (Etype (Base_Type (Entity (Subt)))) =
10563 -- A reference to the current type may appear as the prefix of
10564 -- a 'Class attribute.
10566 elsif Nkind (Subt) = N_Attribute_Reference
10567 and then Attribute_Name (Subt) = Name_Class
10569 return Names_T (Prefix (Subt));
10580 function Mentions_T (Acc_Def : Node_Id) return Boolean is
10581 Param_Spec : Node_Id;
10583 Acc_Subprg : constant Node_Id :=
10584 Access_To_Subprogram_Definition (Acc_Def);
10587 if No (Acc_Subprg) then
10588 return Designates_T (Subtype_Mark (Acc_Def));
10591 -- Component is an access_to_subprogram: examine its formals,
10592 -- and result definition in the case of an access_to_function.
10594 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
10595 while Present (Param_Spec) loop
10596 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
10597 and then Mentions_T (Parameter_Type (Param_Spec))
10601 elsif Designates_T (Parameter_Type (Param_Spec)) then
10608 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
10609 if Nkind (Result_Definition (Acc_Subprg)) =
10610 N_Access_Definition
10612 return Mentions_T (Result_Definition (Acc_Subprg));
10614 return Designates_T (Result_Definition (Acc_Subprg));
10621 -- Start of processing for Check_Anonymous_Access_Components
10624 if No (Comp_List) then
10628 Comp := First (Component_Items (Comp_List));
10629 while Present (Comp) loop
10630 if Nkind (Comp) = N_Component_Declaration
10632 (Access_Definition (Component_Definition (Comp)))
10634 Mentions_T (Access_Definition (Component_Definition (Comp)))
10636 Comp_Def := Component_Definition (Comp);
10638 Access_To_Subprogram_Definition (Access_Definition (Comp_Def));
10640 Build_Incomplete_Type_Declaration;
10641 Anon_Access := Make_Temporary (Loc, 'S');
10643 -- Create a declaration for the anonymous access type: either
10644 -- an access_to_object or an access_to_subprogram.
10646 if Present (Acc_Def) then
10647 if Nkind (Acc_Def) = N_Access_Function_Definition then
10649 Make_Access_Function_Definition (Loc,
10650 Parameter_Specifications =>
10651 Parameter_Specifications (Acc_Def),
10652 Result_Definition => Result_Definition (Acc_Def));
10655 Make_Access_Procedure_Definition (Loc,
10656 Parameter_Specifications =>
10657 Parameter_Specifications (Acc_Def));
10662 Make_Access_To_Object_Definition (Loc,
10663 Subtype_Indication =>
10665 (Subtype_Mark (Access_Definition (Comp_Def))));
10667 Set_Constant_Present
10668 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
10670 (Type_Def, All_Present (Access_Definition (Comp_Def)));
10673 Set_Null_Exclusion_Present
10675 Null_Exclusion_Present (Access_Definition (Comp_Def)));
10678 Make_Full_Type_Declaration (Loc,
10679 Defining_Identifier => Anon_Access,
10680 Type_Definition => Type_Def);
10682 Insert_Before (Typ_Decl, Decl);
10685 -- If an access to subprogram, create the extra formals
10687 if Present (Acc_Def) then
10688 Create_Extra_Formals (Designated_Type (Anon_Access));
10690 -- If an access to object, preserve entity of designated type,
10691 -- for ASIS use, before rewriting the component definition.
10698 Desig := Entity (Subtype_Indication (Type_Def));
10700 -- If the access definition is to the current record,
10701 -- the visible entity at this point is an incomplete
10702 -- type. Retrieve the full view to simplify ASIS queries
10704 if Ekind (Desig) = E_Incomplete_Type then
10705 Desig := Full_View (Desig);
10709 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
10714 Make_Component_Definition (Loc,
10715 Subtype_Indication =>
10716 New_Occurrence_Of (Anon_Access, Loc)));
10718 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
10719 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
10721 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
10724 Set_Is_Local_Anonymous_Access (Anon_Access);
10730 if Present (Variant_Part (Comp_List)) then
10734 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
10735 while Present (V) loop
10736 Check_Anonymous_Access_Components
10737 (Typ_Decl, Typ, Prev, Component_List (V));
10738 Next_Non_Pragma (V);
10742 end Check_Anonymous_Access_Components;
10744 ----------------------
10745 -- Check_Completion --
10746 ----------------------
10748 procedure Check_Completion (Body_Id : Node_Id := Empty) is
10751 procedure Post_Error;
10752 -- Post error message for lack of completion for entity E
10758 procedure Post_Error is
10759 procedure Missing_Body;
10760 -- Output missing body message
10766 procedure Missing_Body is
10768 -- Spec is in same unit, so we can post on spec
10770 if In_Same_Source_Unit (Body_Id, E) then
10771 Error_Msg_N ("missing body for &", E);
10773 -- Spec is in a separate unit, so we have to post on the body
10776 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
10780 -- Start of processing for Post_Error
10783 if not Comes_From_Source (E) then
10784 if Ekind_In (E, E_Task_Type, E_Protected_Type) then
10786 -- It may be an anonymous protected type created for a
10787 -- single variable. Post error on variable, if present.
10793 Var := First_Entity (Current_Scope);
10794 while Present (Var) loop
10795 exit when Etype (Var) = E
10796 and then Comes_From_Source (Var);
10801 if Present (Var) then
10808 -- If a generated entity has no completion, then either previous
10809 -- semantic errors have disabled the expansion phase, or else we had
10810 -- missing subunits, or else we are compiling without expansion,
10811 -- or else something is very wrong.
10813 if not Comes_From_Source (E) then
10815 (Serious_Errors_Detected > 0
10816 or else Configurable_Run_Time_Violations > 0
10817 or else Subunits_Missing
10818 or else not Expander_Active);
10821 -- Here for source entity
10824 -- Here if no body to post the error message, so we post the error
10825 -- on the declaration that has no completion. This is not really
10826 -- the right place to post it, think about this later ???
10828 if No (Body_Id) then
10829 if Is_Type (E) then
10831 ("missing full declaration for }", Parent (E), E);
10833 Error_Msg_NE ("missing body for &", Parent (E), E);
10836 -- Package body has no completion for a declaration that appears
10837 -- in the corresponding spec. Post error on the body, with a
10838 -- reference to the non-completed declaration.
10841 Error_Msg_Sloc := Sloc (E);
10843 if Is_Type (E) then
10844 Error_Msg_NE ("missing full declaration for }!", Body_Id, E);
10846 elsif Is_Overloadable (E)
10847 and then Current_Entity_In_Scope (E) /= E
10849 -- It may be that the completion is mistyped and appears as
10850 -- a distinct overloading of the entity.
10853 Candidate : constant Entity_Id :=
10854 Current_Entity_In_Scope (E);
10855 Decl : constant Node_Id :=
10856 Unit_Declaration_Node (Candidate);
10859 if Is_Overloadable (Candidate)
10860 and then Ekind (Candidate) = Ekind (E)
10861 and then Nkind (Decl) = N_Subprogram_Body
10862 and then Acts_As_Spec (Decl)
10864 Check_Type_Conformant (Candidate, E);
10880 Pack_Id : constant Entity_Id := Current_Scope;
10882 -- Start of processing for Check_Completion
10885 E := First_Entity (Pack_Id);
10886 while Present (E) loop
10887 if Is_Intrinsic_Subprogram (E) then
10890 -- The following situation requires special handling: a child unit
10891 -- that appears in the context clause of the body of its parent:
10893 -- procedure Parent.Child (...);
10895 -- with Parent.Child;
10896 -- package body Parent is
10898 -- Here Parent.Child appears as a local entity, but should not be
10899 -- flagged as requiring completion, because it is a compilation
10902 -- Ignore missing completion for a subprogram that does not come from
10903 -- source (including the _Call primitive operation of RAS types,
10904 -- which has to have the flag Comes_From_Source for other purposes):
10905 -- we assume that the expander will provide the missing completion.
10906 -- In case of previous errors, other expansion actions that provide
10907 -- bodies for null procedures with not be invoked, so inhibit message
10910 -- Note that E_Operator is not in the list that follows, because
10911 -- this kind is reserved for predefined operators, that are
10912 -- intrinsic and do not need completion.
10914 elsif Ekind_In (E, E_Function,
10916 E_Generic_Function,
10917 E_Generic_Procedure)
10919 if Has_Completion (E) then
10922 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
10925 elsif Is_Subprogram (E)
10926 and then (not Comes_From_Source (E)
10927 or else Chars (E) = Name_uCall)
10932 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
10936 elsif Nkind (Parent (E)) = N_Procedure_Specification
10937 and then Null_Present (Parent (E))
10938 and then Serious_Errors_Detected > 0
10946 elsif Is_Entry (E) then
10947 if not Has_Completion (E) and then
10948 (Ekind (Scope (E)) = E_Protected_Object
10949 or else Ekind (Scope (E)) = E_Protected_Type)
10954 elsif Is_Package_Or_Generic_Package (E) then
10955 if Unit_Requires_Body (E) then
10956 if not Has_Completion (E)
10957 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
10963 elsif not Is_Child_Unit (E) then
10964 May_Need_Implicit_Body (E);
10967 -- A formal incomplete type (Ada 2012) does not require a completion;
10968 -- other incomplete type declarations do.
10970 elsif Ekind (E) = E_Incomplete_Type
10971 and then No (Underlying_Type (E))
10972 and then not Is_Generic_Type (E)
10976 elsif Ekind_In (E, E_Task_Type, E_Protected_Type)
10977 and then not Has_Completion (E)
10981 -- A single task declared in the current scope is a constant, verify
10982 -- that the body of its anonymous type is in the same scope. If the
10983 -- task is defined elsewhere, this may be a renaming declaration for
10984 -- which no completion is needed.
10986 elsif Ekind (E) = E_Constant
10987 and then Ekind (Etype (E)) = E_Task_Type
10988 and then not Has_Completion (Etype (E))
10989 and then Scope (Etype (E)) = Current_Scope
10993 elsif Ekind (E) = E_Protected_Object
10994 and then not Has_Completion (Etype (E))
10998 elsif Ekind (E) = E_Record_Type then
10999 if Is_Tagged_Type (E) then
11000 Check_Abstract_Overriding (E);
11001 Check_Conventions (E);
11004 Check_Aliased_Component_Types (E);
11006 elsif Ekind (E) = E_Array_Type then
11007 Check_Aliased_Component_Types (E);
11013 end Check_Completion;
11015 ------------------------------------
11016 -- Check_CPP_Type_Has_No_Defaults --
11017 ------------------------------------
11019 procedure Check_CPP_Type_Has_No_Defaults (T : Entity_Id) is
11020 Tdef : constant Node_Id := Type_Definition (Declaration_Node (T));
11025 -- Obtain the component list
11027 if Nkind (Tdef) = N_Record_Definition then
11028 Clist := Component_List (Tdef);
11029 else pragma Assert (Nkind (Tdef) = N_Derived_Type_Definition);
11030 Clist := Component_List (Record_Extension_Part (Tdef));
11033 -- Check all components to ensure no default expressions
11035 if Present (Clist) then
11036 Comp := First (Component_Items (Clist));
11037 while Present (Comp) loop
11038 if Present (Expression (Comp)) then
11040 ("component of imported 'C'P'P type cannot have "
11041 & "default expression", Expression (Comp));
11047 end Check_CPP_Type_Has_No_Defaults;
11049 ----------------------------
11050 -- Check_Delta_Expression --
11051 ----------------------------
11053 procedure Check_Delta_Expression (E : Node_Id) is
11055 if not (Is_Real_Type (Etype (E))) then
11056 Wrong_Type (E, Any_Real);
11058 elsif not Is_OK_Static_Expression (E) then
11059 Flag_Non_Static_Expr
11060 ("non-static expression used for delta value!", E);
11062 elsif not UR_Is_Positive (Expr_Value_R (E)) then
11063 Error_Msg_N ("delta expression must be positive", E);
11069 -- If any of above errors occurred, then replace the incorrect
11070 -- expression by the real 0.1, which should prevent further errors.
11073 Make_Real_Literal (Sloc (E), Ureal_Tenth));
11074 Analyze_And_Resolve (E, Standard_Float);
11075 end Check_Delta_Expression;
11077 -----------------------------
11078 -- Check_Digits_Expression --
11079 -----------------------------
11081 procedure Check_Digits_Expression (E : Node_Id) is
11083 if not (Is_Integer_Type (Etype (E))) then
11084 Wrong_Type (E, Any_Integer);
11086 elsif not Is_OK_Static_Expression (E) then
11087 Flag_Non_Static_Expr
11088 ("non-static expression used for digits value!", E);
11090 elsif Expr_Value (E) <= 0 then
11091 Error_Msg_N ("digits value must be greater than zero", E);
11097 -- If any of above errors occurred, then replace the incorrect
11098 -- expression by the integer 1, which should prevent further errors.
11100 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
11101 Analyze_And_Resolve (E, Standard_Integer);
11103 end Check_Digits_Expression;
11105 --------------------------
11106 -- Check_Initialization --
11107 --------------------------
11109 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
11111 -- Special processing for limited types
11113 if Is_Limited_Type (T)
11114 and then not In_Instance
11115 and then not In_Inlined_Body
11117 if not OK_For_Limited_Init (T, Exp) then
11119 -- In GNAT mode, this is just a warning, to allow it to be evilly
11120 -- turned off. Otherwise it is a real error.
11124 ("??cannot initialize entities of limited type!", Exp);
11126 elsif Ada_Version < Ada_2005 then
11128 -- The side effect removal machinery may generate illegal Ada
11129 -- code to avoid the usage of access types and 'reference in
11130 -- SPARK mode. Since this is legal code with respect to theorem
11131 -- proving, do not emit the error.
11134 and then Nkind (Exp) = N_Function_Call
11135 and then Nkind (Parent (Exp)) = N_Object_Declaration
11136 and then not Comes_From_Source
11137 (Defining_Identifier (Parent (Exp)))
11143 ("cannot initialize entities of limited type", Exp);
11144 Explain_Limited_Type (T, Exp);
11148 -- Specialize error message according to kind of illegal
11149 -- initial expression.
11151 if Nkind (Exp) = N_Type_Conversion
11152 and then Nkind (Expression (Exp)) = N_Function_Call
11155 ("illegal context for call"
11156 & " to function with limited result", Exp);
11160 ("initialization of limited object requires aggregate "
11161 & "or function call", Exp);
11167 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag gets
11168 -- set unless we can be sure that no range check is required.
11170 if (GNATprove_Mode or not Expander_Active)
11171 and then Is_Scalar_Type (T)
11172 and then not Is_In_Range (Exp, T, Assume_Valid => True)
11174 Set_Do_Range_Check (Exp);
11176 end Check_Initialization;
11178 ----------------------
11179 -- Check_Interfaces --
11180 ----------------------
11182 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
11183 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
11186 Iface_Def : Node_Id;
11187 Iface_Typ : Entity_Id;
11188 Parent_Node : Node_Id;
11190 Is_Task : Boolean := False;
11191 -- Set True if parent type or any progenitor is a task interface
11193 Is_Protected : Boolean := False;
11194 -- Set True if parent type or any progenitor is a protected interface
11196 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
11197 -- Check that a progenitor is compatible with declaration. If an error
11198 -- message is output, it is posted on Error_Node.
11204 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
11205 Iface_Id : constant Entity_Id :=
11206 Defining_Identifier (Parent (Iface_Def));
11207 Type_Def : Node_Id;
11210 if Nkind (N) = N_Private_Extension_Declaration then
11213 Type_Def := Type_Definition (N);
11216 if Is_Task_Interface (Iface_Id) then
11219 elsif Is_Protected_Interface (Iface_Id) then
11220 Is_Protected := True;
11223 if Is_Synchronized_Interface (Iface_Id) then
11225 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
11226 -- extension derived from a synchronized interface must explicitly
11227 -- be declared synchronized, because the full view will be a
11228 -- synchronized type.
11230 if Nkind (N) = N_Private_Extension_Declaration then
11231 if not Synchronized_Present (N) then
11233 ("private extension of& must be explicitly synchronized",
11237 -- However, by 3.9.4(16/2), a full type that is a record extension
11238 -- is never allowed to derive from a synchronized interface (note
11239 -- that interfaces must be excluded from this check, because those
11240 -- are represented by derived type definitions in some cases).
11242 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11243 and then not Interface_Present (Type_Definition (N))
11245 Error_Msg_N ("record extension cannot derive from synchronized "
11246 & "interface", Error_Node);
11250 -- Check that the characteristics of the progenitor are compatible
11251 -- with the explicit qualifier in the declaration.
11252 -- The check only applies to qualifiers that come from source.
11253 -- Limited_Present also appears in the declaration of corresponding
11254 -- records, and the check does not apply to them.
11256 if Limited_Present (Type_Def)
11258 Is_Concurrent_Record_Type (Defining_Identifier (N))
11260 if Is_Limited_Interface (Parent_Type)
11261 and then not Is_Limited_Interface (Iface_Id)
11264 ("progenitor & must be limited interface",
11265 Error_Node, Iface_Id);
11268 (Task_Present (Iface_Def)
11269 or else Protected_Present (Iface_Def)
11270 or else Synchronized_Present (Iface_Def))
11271 and then Nkind (N) /= N_Private_Extension_Declaration
11272 and then not Error_Posted (N)
11275 ("progenitor & must be limited interface",
11276 Error_Node, Iface_Id);
11279 -- Protected interfaces can only inherit from limited, synchronized
11280 -- or protected interfaces.
11282 elsif Nkind (N) = N_Full_Type_Declaration
11283 and then Protected_Present (Type_Def)
11285 if Limited_Present (Iface_Def)
11286 or else Synchronized_Present (Iface_Def)
11287 or else Protected_Present (Iface_Def)
11291 elsif Task_Present (Iface_Def) then
11292 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11293 & "from task interface", Error_Node);
11296 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11297 & "from non-limited interface", Error_Node);
11300 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
11301 -- limited and synchronized.
11303 elsif Synchronized_Present (Type_Def) then
11304 if Limited_Present (Iface_Def)
11305 or else Synchronized_Present (Iface_Def)
11309 elsif Protected_Present (Iface_Def)
11310 and then Nkind (N) /= N_Private_Extension_Declaration
11312 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11313 & "from protected interface", Error_Node);
11315 elsif Task_Present (Iface_Def)
11316 and then Nkind (N) /= N_Private_Extension_Declaration
11318 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11319 & "from task interface", Error_Node);
11321 elsif not Is_Limited_Interface (Iface_Id) then
11322 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11323 & "from non-limited interface", Error_Node);
11326 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
11327 -- synchronized or task interfaces.
11329 elsif Nkind (N) = N_Full_Type_Declaration
11330 and then Task_Present (Type_Def)
11332 if Limited_Present (Iface_Def)
11333 or else Synchronized_Present (Iface_Def)
11334 or else Task_Present (Iface_Def)
11338 elsif Protected_Present (Iface_Def) then
11339 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11340 & "protected interface", Error_Node);
11343 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11344 & "non-limited interface", Error_Node);
11349 -- Start of processing for Check_Interfaces
11352 if Is_Interface (Parent_Type) then
11353 if Is_Task_Interface (Parent_Type) then
11356 elsif Is_Protected_Interface (Parent_Type) then
11357 Is_Protected := True;
11361 if Nkind (N) = N_Private_Extension_Declaration then
11363 -- Check that progenitors are compatible with declaration
11365 Iface := First (Interface_List (Def));
11366 while Present (Iface) loop
11367 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11369 Parent_Node := Parent (Base_Type (Iface_Typ));
11370 Iface_Def := Type_Definition (Parent_Node);
11372 if not Is_Interface (Iface_Typ) then
11373 Diagnose_Interface (Iface, Iface_Typ);
11375 Check_Ifaces (Iface_Def, Iface);
11381 if Is_Task and Is_Protected then
11383 ("type cannot derive from task and protected interface", N);
11389 -- Full type declaration of derived type.
11390 -- Check compatibility with parent if it is interface type
11392 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11393 and then Is_Interface (Parent_Type)
11395 Parent_Node := Parent (Parent_Type);
11397 -- More detailed checks for interface varieties
11400 (Iface_Def => Type_Definition (Parent_Node),
11401 Error_Node => Subtype_Indication (Type_Definition (N)));
11404 Iface := First (Interface_List (Def));
11405 while Present (Iface) loop
11406 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11408 Parent_Node := Parent (Base_Type (Iface_Typ));
11409 Iface_Def := Type_Definition (Parent_Node);
11411 if not Is_Interface (Iface_Typ) then
11412 Diagnose_Interface (Iface, Iface_Typ);
11415 -- "The declaration of a specific descendant of an interface
11416 -- type freezes the interface type" RM 13.14
11418 Freeze_Before (N, Iface_Typ);
11419 Check_Ifaces (Iface_Def, Error_Node => Iface);
11425 if Is_Task and Is_Protected then
11427 ("type cannot derive from task and protected interface", N);
11429 end Check_Interfaces;
11431 ------------------------------------
11432 -- Check_Or_Process_Discriminants --
11433 ------------------------------------
11435 -- If an incomplete or private type declaration was already given for the
11436 -- type, the discriminants may have already been processed if they were
11437 -- present on the incomplete declaration. In this case a full conformance
11438 -- check has been performed in Find_Type_Name, and we then recheck here
11439 -- some properties that can't be checked on the partial view alone.
11440 -- Otherwise we call Process_Discriminants.
11442 procedure Check_Or_Process_Discriminants
11445 Prev : Entity_Id := Empty)
11448 if Has_Discriminants (T) then
11450 -- Discriminants are already set on T if they were already present
11451 -- on the partial view. Make them visible to component declarations.
11455 -- Discriminant on T (full view) referencing expr on partial view
11457 Prev_D : Entity_Id;
11458 -- Entity of corresponding discriminant on partial view
11461 -- Discriminant specification for full view, expression is
11462 -- the syntactic copy on full view (which has been checked for
11463 -- conformance with partial view), only used here to post error
11467 D := First_Discriminant (T);
11468 New_D := First (Discriminant_Specifications (N));
11469 while Present (D) loop
11470 Prev_D := Current_Entity (D);
11471 Set_Current_Entity (D);
11472 Set_Is_Immediately_Visible (D);
11473 Set_Homonym (D, Prev_D);
11475 -- Handle the case where there is an untagged partial view and
11476 -- the full view is tagged: must disallow discriminants with
11477 -- defaults, unless compiling for Ada 2012, which allows a
11478 -- limited tagged type to have defaulted discriminants (see
11479 -- AI05-0214). However, suppress error here if it was already
11480 -- reported on the default expression of the partial view.
11482 if Is_Tagged_Type (T)
11483 and then Present (Expression (Parent (D)))
11484 and then (not Is_Limited_Type (Current_Scope)
11485 or else Ada_Version < Ada_2012)
11486 and then not Error_Posted (Expression (Parent (D)))
11488 if Ada_Version >= Ada_2012 then
11490 ("discriminants of nonlimited tagged type cannot have "
11492 Expression (New_D));
11495 ("discriminants of tagged type cannot have defaults",
11496 Expression (New_D));
11500 -- Ada 2005 (AI-230): Access discriminant allowed in
11501 -- non-limited record types.
11503 if Ada_Version < Ada_2005 then
11505 -- This restriction gets applied to the full type here. It
11506 -- has already been applied earlier to the partial view.
11508 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
11511 Next_Discriminant (D);
11516 elsif Present (Discriminant_Specifications (N)) then
11517 Process_Discriminants (N, Prev);
11519 end Check_Or_Process_Discriminants;
11521 ----------------------
11522 -- Check_Real_Bound --
11523 ----------------------
11525 procedure Check_Real_Bound (Bound : Node_Id) is
11527 if not Is_Real_Type (Etype (Bound)) then
11529 ("bound in real type definition must be of real type", Bound);
11531 elsif not Is_OK_Static_Expression (Bound) then
11532 Flag_Non_Static_Expr
11533 ("non-static expression used for real type bound!", Bound);
11540 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
11542 Resolve (Bound, Standard_Float);
11543 end Check_Real_Bound;
11545 ------------------------------
11546 -- Complete_Private_Subtype --
11547 ------------------------------
11549 procedure Complete_Private_Subtype
11552 Full_Base : Entity_Id;
11553 Related_Nod : Node_Id)
11555 Save_Next_Entity : Entity_Id;
11556 Save_Homonym : Entity_Id;
11559 -- Set semantic attributes for (implicit) private subtype completion.
11560 -- If the full type has no discriminants, then it is a copy of the
11561 -- full view of the base. Otherwise, it is a subtype of the base with
11562 -- a possible discriminant constraint. Save and restore the original
11563 -- Next_Entity field of full to ensure that the calls to Copy_Node do
11564 -- not corrupt the entity chain.
11566 -- Note that the type of the full view is the same entity as the type
11567 -- of the partial view. In this fashion, the subtype has access to the
11568 -- correct view of the parent.
11570 Save_Next_Entity := Next_Entity (Full);
11571 Save_Homonym := Homonym (Priv);
11573 case Ekind (Full_Base) is
11574 when E_Record_Type |
11580 Copy_Node (Priv, Full);
11582 Set_Has_Discriminants
11583 (Full, Has_Discriminants (Full_Base));
11584 Set_Has_Unknown_Discriminants
11585 (Full, Has_Unknown_Discriminants (Full_Base));
11586 Set_First_Entity (Full, First_Entity (Full_Base));
11587 Set_Last_Entity (Full, Last_Entity (Full_Base));
11589 -- If the underlying base type is constrained, we know that the
11590 -- full view of the subtype is constrained as well (the converse
11591 -- is not necessarily true).
11593 if Is_Constrained (Full_Base) then
11594 Set_Is_Constrained (Full);
11598 Copy_Node (Full_Base, Full);
11600 Set_Chars (Full, Chars (Priv));
11601 Conditional_Delay (Full, Priv);
11602 Set_Sloc (Full, Sloc (Priv));
11605 Set_Next_Entity (Full, Save_Next_Entity);
11606 Set_Homonym (Full, Save_Homonym);
11607 Set_Associated_Node_For_Itype (Full, Related_Nod);
11609 -- Set common attributes for all subtypes: kind, convention, etc.
11611 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
11612 Set_Convention (Full, Convention (Full_Base));
11614 -- The Etype of the full view is inconsistent. Gigi needs to see the
11615 -- structural full view, which is what the current scheme gives: the
11616 -- Etype of the full view is the etype of the full base. However, if the
11617 -- full base is a derived type, the full view then looks like a subtype
11618 -- of the parent, not a subtype of the full base. If instead we write:
11620 -- Set_Etype (Full, Full_Base);
11622 -- then we get inconsistencies in the front-end (confusion between
11623 -- views). Several outstanding bugs are related to this ???
11625 Set_Is_First_Subtype (Full, False);
11626 Set_Scope (Full, Scope (Priv));
11627 Set_Size_Info (Full, Full_Base);
11628 Set_RM_Size (Full, RM_Size (Full_Base));
11629 Set_Is_Itype (Full);
11631 -- A subtype of a private-type-without-discriminants, whose full-view
11632 -- has discriminants with default expressions, is not constrained.
11634 if not Has_Discriminants (Priv) then
11635 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
11637 if Has_Discriminants (Full_Base) then
11638 Set_Discriminant_Constraint
11639 (Full, Discriminant_Constraint (Full_Base));
11641 -- The partial view may have been indefinite, the full view
11644 Set_Has_Unknown_Discriminants
11645 (Full, Has_Unknown_Discriminants (Full_Base));
11649 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
11650 Set_Depends_On_Private (Full, Has_Private_Component (Full));
11652 -- Freeze the private subtype entity if its parent is delayed, and not
11653 -- already frozen. We skip this processing if the type is an anonymous
11654 -- subtype of a record component, or is the corresponding record of a
11655 -- protected type, since these are processed when the enclosing type
11658 if not Is_Type (Scope (Full)) then
11659 Set_Has_Delayed_Freeze (Full,
11660 Has_Delayed_Freeze (Full_Base)
11661 and then (not Is_Frozen (Full_Base)));
11664 Set_Freeze_Node (Full, Empty);
11665 Set_Is_Frozen (Full, False);
11666 Set_Full_View (Priv, Full);
11668 if Has_Discriminants (Full) then
11669 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
11670 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
11672 if Has_Unknown_Discriminants (Full) then
11673 Set_Discriminant_Constraint (Full, No_Elist);
11677 if Ekind (Full_Base) = E_Record_Type
11678 and then Has_Discriminants (Full_Base)
11679 and then Has_Discriminants (Priv) -- might not, if errors
11680 and then not Has_Unknown_Discriminants (Priv)
11681 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
11683 Create_Constrained_Components
11684 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
11686 -- If the full base is itself derived from private, build a congruent
11687 -- subtype of its underlying type, for use by the back end. For a
11688 -- constrained record component, the declaration cannot be placed on
11689 -- the component list, but it must nevertheless be built an analyzed, to
11690 -- supply enough information for Gigi to compute the size of component.
11692 elsif Ekind (Full_Base) in Private_Kind
11693 and then Is_Derived_Type (Full_Base)
11694 and then Has_Discriminants (Full_Base)
11695 and then (Ekind (Current_Scope) /= E_Record_Subtype)
11697 if not Is_Itype (Priv)
11699 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
11701 Build_Underlying_Full_View
11702 (Parent (Priv), Full, Etype (Full_Base));
11704 elsif Nkind (Related_Nod) = N_Component_Declaration then
11705 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
11708 elsif Is_Record_Type (Full_Base) then
11710 -- Show Full is simply a renaming of Full_Base
11712 Set_Cloned_Subtype (Full, Full_Base);
11715 -- It is unsafe to share the bounds of a scalar type, because the Itype
11716 -- is elaborated on demand, and if a bound is non-static then different
11717 -- orders of elaboration in different units will lead to different
11718 -- external symbols.
11720 if Is_Scalar_Type (Full_Base) then
11721 Set_Scalar_Range (Full,
11722 Make_Range (Sloc (Related_Nod),
11724 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
11726 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
11728 -- This completion inherits the bounds of the full parent, but if
11729 -- the parent is an unconstrained floating point type, so is the
11732 if Is_Floating_Point_Type (Full_Base) then
11733 Set_Includes_Infinities
11734 (Scalar_Range (Full), Has_Infinities (Full_Base));
11738 -- ??? It seems that a lot of fields are missing that should be copied
11739 -- from Full_Base to Full. Here are some that are introduced in a
11740 -- non-disruptive way but a cleanup is necessary.
11742 if Is_Tagged_Type (Full_Base) then
11743 Set_Is_Tagged_Type (Full);
11744 Set_Direct_Primitive_Operations
11745 (Full, Direct_Primitive_Operations (Full_Base));
11746 Set_No_Tagged_Streams_Pragma
11747 (Full, No_Tagged_Streams_Pragma (Full_Base));
11749 -- Inherit class_wide type of full_base in case the partial view was
11750 -- not tagged. Otherwise it has already been created when the private
11751 -- subtype was analyzed.
11753 if No (Class_Wide_Type (Full)) then
11754 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
11757 -- If this is a subtype of a protected or task type, constrain its
11758 -- corresponding record, unless this is a subtype without constraints,
11759 -- i.e. a simple renaming as with an actual subtype in an instance.
11761 elsif Is_Concurrent_Type (Full_Base) then
11762 if Has_Discriminants (Full)
11763 and then Present (Corresponding_Record_Type (Full_Base))
11765 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
11767 Set_Corresponding_Record_Type (Full,
11768 Constrain_Corresponding_Record
11769 (Full, Corresponding_Record_Type (Full_Base), Related_Nod));
11772 Set_Corresponding_Record_Type (Full,
11773 Corresponding_Record_Type (Full_Base));
11777 -- Link rep item chain, and also setting of Has_Predicates from private
11778 -- subtype to full subtype, since we will need these on the full subtype
11779 -- to create the predicate function. Note that the full subtype may
11780 -- already have rep items, inherited from the full view of the base
11781 -- type, so we must be sure not to overwrite these entries.
11786 Next_Item : Node_Id;
11789 Item := First_Rep_Item (Full);
11791 -- If no existing rep items on full type, we can just link directly
11792 -- to the list of items on the private type, if any exist.. Same if
11793 -- the rep items are only those inherited from the base
11796 or else Nkind (Item) /= N_Aspect_Specification
11797 or else Entity (Item) = Full_Base)
11798 and then Present (First_Rep_Item (Priv))
11800 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
11802 -- Otherwise, search to the end of items currently linked to the full
11803 -- subtype and append the private items to the end. However, if Priv
11804 -- and Full already have the same list of rep items, then the append
11805 -- is not done, as that would create a circularity.
11807 elsif Item /= First_Rep_Item (Priv) then
11810 Next_Item := Next_Rep_Item (Item);
11811 exit when No (Next_Item);
11814 -- If the private view has aspect specifications, the full view
11815 -- inherits them. Since these aspects may already have been
11816 -- attached to the full view during derivation, do not append
11817 -- them if already present.
11819 if Item = First_Rep_Item (Priv) then
11825 -- And link the private type items at the end of the chain
11828 Set_Next_Rep_Item (Item, First_Rep_Item (Priv));
11833 -- Make sure Has_Predicates is set on full type if it is set on the
11834 -- private type. Note that it may already be set on the full type and
11835 -- if so, we don't want to unset it. Similarly, propagate information
11836 -- about delayed aspects, because the corresponding pragmas must be
11837 -- analyzed when one of the views is frozen. This last step is needed
11838 -- in particular when the full type is a scalar type for which an
11839 -- anonymous base type is constructed.
11841 -- The predicate functions are generated either at the freeze point
11842 -- of the type or at the end of the visible part, and we must avoid
11843 -- generating them twice.
11845 if Has_Predicates (Priv) then
11846 Set_Has_Predicates (Full);
11848 if Present (Predicate_Function (Priv))
11849 and then No (Predicate_Function (Full))
11851 Set_Predicate_Function (Full, Predicate_Function (Priv));
11855 if Has_Delayed_Aspects (Priv) then
11856 Set_Has_Delayed_Aspects (Full);
11858 end Complete_Private_Subtype;
11860 ----------------------------
11861 -- Constant_Redeclaration --
11862 ----------------------------
11864 procedure Constant_Redeclaration
11869 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
11870 Obj_Def : constant Node_Id := Object_Definition (N);
11873 procedure Check_Possible_Deferred_Completion
11874 (Prev_Id : Entity_Id;
11875 Prev_Obj_Def : Node_Id;
11876 Curr_Obj_Def : Node_Id);
11877 -- Determine whether the two object definitions describe the partial
11878 -- and the full view of a constrained deferred constant. Generate
11879 -- a subtype for the full view and verify that it statically matches
11880 -- the subtype of the partial view.
11882 procedure Check_Recursive_Declaration (Typ : Entity_Id);
11883 -- If deferred constant is an access type initialized with an allocator,
11884 -- check whether there is an illegal recursion in the definition,
11885 -- through a default value of some record subcomponent. This is normally
11886 -- detected when generating init procs, but requires this additional
11887 -- mechanism when expansion is disabled.
11889 ----------------------------------------
11890 -- Check_Possible_Deferred_Completion --
11891 ----------------------------------------
11893 procedure Check_Possible_Deferred_Completion
11894 (Prev_Id : Entity_Id;
11895 Prev_Obj_Def : Node_Id;
11896 Curr_Obj_Def : Node_Id)
11899 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
11900 and then Present (Constraint (Prev_Obj_Def))
11901 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
11902 and then Present (Constraint (Curr_Obj_Def))
11905 Loc : constant Source_Ptr := Sloc (N);
11906 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'S');
11907 Decl : constant Node_Id :=
11908 Make_Subtype_Declaration (Loc,
11909 Defining_Identifier => Def_Id,
11910 Subtype_Indication =>
11911 Relocate_Node (Curr_Obj_Def));
11914 Insert_Before_And_Analyze (N, Decl);
11915 Set_Etype (Id, Def_Id);
11917 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
11918 Error_Msg_Sloc := Sloc (Prev_Id);
11919 Error_Msg_N ("subtype does not statically match deferred "
11920 & "declaration #", N);
11924 end Check_Possible_Deferred_Completion;
11926 ---------------------------------
11927 -- Check_Recursive_Declaration --
11928 ---------------------------------
11930 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
11934 if Is_Record_Type (Typ) then
11935 Comp := First_Component (Typ);
11936 while Present (Comp) loop
11937 if Comes_From_Source (Comp) then
11938 if Present (Expression (Parent (Comp)))
11939 and then Is_Entity_Name (Expression (Parent (Comp)))
11940 and then Entity (Expression (Parent (Comp))) = Prev
11942 Error_Msg_Sloc := Sloc (Parent (Comp));
11944 ("illegal circularity with declaration for & #",
11948 elsif Is_Record_Type (Etype (Comp)) then
11949 Check_Recursive_Declaration (Etype (Comp));
11953 Next_Component (Comp);
11956 end Check_Recursive_Declaration;
11958 -- Start of processing for Constant_Redeclaration
11961 if Nkind (Parent (Prev)) = N_Object_Declaration then
11962 if Nkind (Object_Definition
11963 (Parent (Prev))) = N_Subtype_Indication
11965 -- Find type of new declaration. The constraints of the two
11966 -- views must match statically, but there is no point in
11967 -- creating an itype for the full view.
11969 if Nkind (Obj_Def) = N_Subtype_Indication then
11970 Find_Type (Subtype_Mark (Obj_Def));
11971 New_T := Entity (Subtype_Mark (Obj_Def));
11974 Find_Type (Obj_Def);
11975 New_T := Entity (Obj_Def);
11981 -- The full view may impose a constraint, even if the partial
11982 -- view does not, so construct the subtype.
11984 New_T := Find_Type_Of_Object (Obj_Def, N);
11989 -- Current declaration is illegal, diagnosed below in Enter_Name
11995 -- If previous full declaration or a renaming declaration exists, or if
11996 -- a homograph is present, let Enter_Name handle it, either with an
11997 -- error or with the removal of an overridden implicit subprogram.
11998 -- The previous one is a full declaration if it has an expression
11999 -- (which in the case of an aggregate is indicated by the Init flag).
12001 if Ekind (Prev) /= E_Constant
12002 or else Nkind (Parent (Prev)) = N_Object_Renaming_Declaration
12003 or else Present (Expression (Parent (Prev)))
12004 or else Has_Init_Expression (Parent (Prev))
12005 or else Present (Full_View (Prev))
12009 -- Verify that types of both declarations match, or else that both types
12010 -- are anonymous access types whose designated subtypes statically match
12011 -- (as allowed in Ada 2005 by AI-385).
12013 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
12015 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
12016 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
12017 or else Is_Access_Constant (Etype (New_T)) /=
12018 Is_Access_Constant (Etype (Prev))
12019 or else Can_Never_Be_Null (Etype (New_T)) /=
12020 Can_Never_Be_Null (Etype (Prev))
12021 or else Null_Exclusion_Present (Parent (Prev)) /=
12022 Null_Exclusion_Present (Parent (Id))
12023 or else not Subtypes_Statically_Match
12024 (Designated_Type (Etype (Prev)),
12025 Designated_Type (Etype (New_T))))
12027 Error_Msg_Sloc := Sloc (Prev);
12028 Error_Msg_N ("type does not match declaration#", N);
12029 Set_Full_View (Prev, Id);
12030 Set_Etype (Id, Any_Type);
12032 -- A deferred constant whose type is an anonymous array is always
12033 -- illegal (unless imported). A detailed error message might be
12034 -- helpful for Ada beginners.
12036 if Nkind (Object_Definition (Parent (Prev)))
12037 = N_Constrained_Array_Definition
12038 and then Nkind (Object_Definition (N))
12039 = N_Constrained_Array_Definition
12041 Error_Msg_N ("\each anonymous array is a distinct type", N);
12042 Error_Msg_N ("a deferred constant must have a named type",
12043 Object_Definition (Parent (Prev)));
12047 Null_Exclusion_Present (Parent (Prev))
12048 and then not Null_Exclusion_Present (N)
12050 Error_Msg_Sloc := Sloc (Prev);
12051 Error_Msg_N ("null-exclusion does not match declaration#", N);
12052 Set_Full_View (Prev, Id);
12053 Set_Etype (Id, Any_Type);
12055 -- If so, process the full constant declaration
12058 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
12059 -- the deferred declaration is constrained, then the subtype defined
12060 -- by the subtype_indication in the full declaration shall match it
12063 Check_Possible_Deferred_Completion
12065 Prev_Obj_Def => Object_Definition (Parent (Prev)),
12066 Curr_Obj_Def => Obj_Def);
12068 Set_Full_View (Prev, Id);
12069 Set_Is_Public (Id, Is_Public (Prev));
12070 Set_Is_Internal (Id);
12071 Append_Entity (Id, Current_Scope);
12073 -- Check ALIASED present if present before (RM 7.4(7))
12075 if Is_Aliased (Prev)
12076 and then not Aliased_Present (N)
12078 Error_Msg_Sloc := Sloc (Prev);
12079 Error_Msg_N ("ALIASED required (see declaration #)", N);
12082 -- Check that placement is in private part and that the incomplete
12083 -- declaration appeared in the visible part.
12085 if Ekind (Current_Scope) = E_Package
12086 and then not In_Private_Part (Current_Scope)
12088 Error_Msg_Sloc := Sloc (Prev);
12090 ("full constant for declaration # must be in private part", N);
12092 elsif Ekind (Current_Scope) = E_Package
12094 List_Containing (Parent (Prev)) /=
12095 Visible_Declarations (Package_Specification (Current_Scope))
12098 ("deferred constant must be declared in visible part",
12102 if Is_Access_Type (T)
12103 and then Nkind (Expression (N)) = N_Allocator
12105 Check_Recursive_Declaration (Designated_Type (T));
12108 -- A deferred constant is a visible entity. If type has invariants,
12109 -- verify that the initial value satisfies them.
12111 if Has_Invariants (T) and then Present (Invariant_Procedure (T)) then
12113 Make_Invariant_Call (New_Occurrence_Of (Prev, Sloc (N))));
12116 end Constant_Redeclaration;
12118 ----------------------
12119 -- Constrain_Access --
12120 ----------------------
12122 procedure Constrain_Access
12123 (Def_Id : in out Entity_Id;
12125 Related_Nod : Node_Id)
12127 T : constant Entity_Id := Entity (Subtype_Mark (S));
12128 Desig_Type : constant Entity_Id := Designated_Type (T);
12129 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
12130 Constraint_OK : Boolean := True;
12133 if Is_Array_Type (Desig_Type) then
12134 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
12136 elsif (Is_Record_Type (Desig_Type)
12137 or else Is_Incomplete_Or_Private_Type (Desig_Type))
12138 and then not Is_Constrained (Desig_Type)
12140 -- ??? The following code is a temporary bypass to ignore a
12141 -- discriminant constraint on access type if it is constraining
12142 -- the current record. Avoid creating the implicit subtype of the
12143 -- record we are currently compiling since right now, we cannot
12144 -- handle these. For now, just return the access type itself.
12146 if Desig_Type = Current_Scope
12147 and then No (Def_Id)
12149 Set_Ekind (Desig_Subtype, E_Record_Subtype);
12150 Def_Id := Entity (Subtype_Mark (S));
12152 -- This call added to ensure that the constraint is analyzed
12153 -- (needed for a B test). Note that we still return early from
12154 -- this procedure to avoid recursive processing. ???
12156 Constrain_Discriminated_Type
12157 (Desig_Subtype, S, Related_Nod, For_Access => True);
12161 -- Enforce rule that the constraint is illegal if there is an
12162 -- unconstrained view of the designated type. This means that the
12163 -- partial view (either a private type declaration or a derivation
12164 -- from a private type) has no discriminants. (Defect Report
12165 -- 8652/0008, Technical Corrigendum 1, checked by ACATS B371001).
12167 -- Rule updated for Ada 2005: The private type is said to have
12168 -- a constrained partial view, given that objects of the type
12169 -- can be declared. Furthermore, the rule applies to all access
12170 -- types, unlike the rule concerning default discriminants (see
12173 if (Ekind (T) = E_General_Access_Type or else Ada_Version >= Ada_2005)
12174 and then Has_Private_Declaration (Desig_Type)
12175 and then In_Open_Scopes (Scope (Desig_Type))
12176 and then Has_Discriminants (Desig_Type)
12179 Pack : constant Node_Id :=
12180 Unit_Declaration_Node (Scope (Desig_Type));
12185 if Nkind (Pack) = N_Package_Declaration then
12186 Decls := Visible_Declarations (Specification (Pack));
12187 Decl := First (Decls);
12188 while Present (Decl) loop
12189 if (Nkind (Decl) = N_Private_Type_Declaration
12190 and then Chars (Defining_Identifier (Decl)) =
12191 Chars (Desig_Type))
12194 (Nkind (Decl) = N_Full_Type_Declaration
12196 Chars (Defining_Identifier (Decl)) =
12198 and then Is_Derived_Type (Desig_Type)
12200 Has_Private_Declaration (Etype (Desig_Type)))
12202 if No (Discriminant_Specifications (Decl)) then
12204 ("cannot constrain access type if designated "
12205 & "type has constrained partial view", S);
12217 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
12218 For_Access => True);
12220 elsif Is_Concurrent_Type (Desig_Type)
12221 and then not Is_Constrained (Desig_Type)
12223 Constrain_Concurrent (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
12226 Error_Msg_N ("invalid constraint on access type", S);
12228 -- We simply ignore an invalid constraint
12230 Desig_Subtype := Desig_Type;
12231 Constraint_OK := False;
12234 if No (Def_Id) then
12235 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
12237 Set_Ekind (Def_Id, E_Access_Subtype);
12240 if Constraint_OK then
12241 Set_Etype (Def_Id, Base_Type (T));
12243 if Is_Private_Type (Desig_Type) then
12244 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
12247 Set_Etype (Def_Id, Any_Type);
12250 Set_Size_Info (Def_Id, T);
12251 Set_Is_Constrained (Def_Id, Constraint_OK);
12252 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
12253 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12254 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
12256 Conditional_Delay (Def_Id, T);
12258 -- AI-363 : Subtypes of general access types whose designated types have
12259 -- default discriminants are disallowed. In instances, the rule has to
12260 -- be checked against the actual, of which T is the subtype. In a
12261 -- generic body, the rule is checked assuming that the actual type has
12262 -- defaulted discriminants.
12264 if Ada_Version >= Ada_2005 or else Warn_On_Ada_2005_Compatibility then
12265 if Ekind (Base_Type (T)) = E_General_Access_Type
12266 and then Has_Defaulted_Discriminants (Desig_Type)
12268 if Ada_Version < Ada_2005 then
12270 ("access subtype of general access type would not " &
12271 "be allowed in Ada 2005?y?", S);
12274 ("access subtype of general access type not allowed", S);
12277 Error_Msg_N ("\discriminants have defaults", S);
12279 elsif Is_Access_Type (T)
12280 and then Is_Generic_Type (Desig_Type)
12281 and then Has_Discriminants (Desig_Type)
12282 and then In_Package_Body (Current_Scope)
12284 if Ada_Version < Ada_2005 then
12286 ("access subtype would not be allowed in generic body "
12287 & "in Ada 2005?y?", S);
12290 ("access subtype not allowed in generic body", S);
12294 ("\designated type is a discriminated formal", S);
12297 end Constrain_Access;
12299 ---------------------
12300 -- Constrain_Array --
12301 ---------------------
12303 procedure Constrain_Array
12304 (Def_Id : in out Entity_Id;
12306 Related_Nod : Node_Id;
12307 Related_Id : Entity_Id;
12308 Suffix : Character)
12310 C : constant Node_Id := Constraint (SI);
12311 Number_Of_Constraints : Nat := 0;
12314 Constraint_OK : Boolean := True;
12317 T := Entity (Subtype_Mark (SI));
12319 if Is_Access_Type (T) then
12320 T := Designated_Type (T);
12323 -- If an index constraint follows a subtype mark in a subtype indication
12324 -- then the type or subtype denoted by the subtype mark must not already
12325 -- impose an index constraint. The subtype mark must denote either an
12326 -- unconstrained array type or an access type whose designated type
12327 -- is such an array type... (RM 3.6.1)
12329 if Is_Constrained (T) then
12330 Error_Msg_N ("array type is already constrained", Subtype_Mark (SI));
12331 Constraint_OK := False;
12334 S := First (Constraints (C));
12335 while Present (S) loop
12336 Number_Of_Constraints := Number_Of_Constraints + 1;
12340 -- In either case, the index constraint must provide a discrete
12341 -- range for each index of the array type and the type of each
12342 -- discrete range must be the same as that of the corresponding
12343 -- index. (RM 3.6.1)
12345 if Number_Of_Constraints /= Number_Dimensions (T) then
12346 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
12347 Constraint_OK := False;
12350 S := First (Constraints (C));
12351 Index := First_Index (T);
12354 -- Apply constraints to each index type
12356 for J in 1 .. Number_Of_Constraints loop
12357 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
12365 if No (Def_Id) then
12367 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
12368 Set_Parent (Def_Id, Related_Nod);
12371 Set_Ekind (Def_Id, E_Array_Subtype);
12374 Set_Size_Info (Def_Id, (T));
12375 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12376 Set_Etype (Def_Id, Base_Type (T));
12378 if Constraint_OK then
12379 Set_First_Index (Def_Id, First (Constraints (C)));
12381 Set_First_Index (Def_Id, First_Index (T));
12384 Set_Is_Constrained (Def_Id, True);
12385 Set_Is_Aliased (Def_Id, Is_Aliased (T));
12386 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12388 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
12389 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
12391 -- A subtype does not inherit the Packed_Array_Impl_Type of is parent.
12392 -- We need to initialize the attribute because if Def_Id is previously
12393 -- analyzed through a limited_with clause, it will have the attributes
12394 -- of an incomplete type, one of which is an Elist that overlaps the
12395 -- Packed_Array_Impl_Type field.
12397 Set_Packed_Array_Impl_Type (Def_Id, Empty);
12399 -- Build a freeze node if parent still needs one. Also make sure that
12400 -- the Depends_On_Private status is set because the subtype will need
12401 -- reprocessing at the time the base type does, and also we must set a
12402 -- conditional delay.
12404 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
12405 Conditional_Delay (Def_Id, T);
12406 end Constrain_Array;
12408 ------------------------------
12409 -- Constrain_Component_Type --
12410 ------------------------------
12412 function Constrain_Component_Type
12414 Constrained_Typ : Entity_Id;
12415 Related_Node : Node_Id;
12417 Constraints : Elist_Id) return Entity_Id
12419 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
12420 Compon_Type : constant Entity_Id := Etype (Comp);
12422 function Build_Constrained_Array_Type
12423 (Old_Type : Entity_Id) return Entity_Id;
12424 -- If Old_Type is an array type, one of whose indexes is constrained
12425 -- by a discriminant, build an Itype whose constraint replaces the
12426 -- discriminant with its value in the constraint.
12428 function Build_Constrained_Discriminated_Type
12429 (Old_Type : Entity_Id) return Entity_Id;
12430 -- Ditto for record components
12432 function Build_Constrained_Access_Type
12433 (Old_Type : Entity_Id) return Entity_Id;
12434 -- Ditto for access types. Makes use of previous two functions, to
12435 -- constrain designated type.
12437 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
12438 -- T is an array or discriminated type, C is a list of constraints
12439 -- that apply to T. This routine builds the constrained subtype.
12441 function Is_Discriminant (Expr : Node_Id) return Boolean;
12442 -- Returns True if Expr is a discriminant
12444 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
12445 -- Find the value of discriminant Discrim in Constraint
12447 -----------------------------------
12448 -- Build_Constrained_Access_Type --
12449 -----------------------------------
12451 function Build_Constrained_Access_Type
12452 (Old_Type : Entity_Id) return Entity_Id
12454 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
12456 Desig_Subtype : Entity_Id;
12460 -- if the original access type was not embedded in the enclosing
12461 -- type definition, there is no need to produce a new access
12462 -- subtype. In fact every access type with an explicit constraint
12463 -- generates an itype whose scope is the enclosing record.
12465 if not Is_Type (Scope (Old_Type)) then
12468 elsif Is_Array_Type (Desig_Type) then
12469 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
12471 elsif Has_Discriminants (Desig_Type) then
12473 -- This may be an access type to an enclosing record type for
12474 -- which we are constructing the constrained components. Return
12475 -- the enclosing record subtype. This is not always correct,
12476 -- but avoids infinite recursion. ???
12478 Desig_Subtype := Any_Type;
12480 for J in reverse 0 .. Scope_Stack.Last loop
12481 Scop := Scope_Stack.Table (J).Entity;
12484 and then Base_Type (Scop) = Base_Type (Desig_Type)
12486 Desig_Subtype := Scop;
12489 exit when not Is_Type (Scop);
12492 if Desig_Subtype = Any_Type then
12494 Build_Constrained_Discriminated_Type (Desig_Type);
12501 if Desig_Subtype /= Desig_Type then
12503 -- The Related_Node better be here or else we won't be able
12504 -- to attach new itypes to a node in the tree.
12506 pragma Assert (Present (Related_Node));
12508 Itype := Create_Itype (E_Access_Subtype, Related_Node);
12510 Set_Etype (Itype, Base_Type (Old_Type));
12511 Set_Size_Info (Itype, (Old_Type));
12512 Set_Directly_Designated_Type (Itype, Desig_Subtype);
12513 Set_Depends_On_Private (Itype, Has_Private_Component
12515 Set_Is_Access_Constant (Itype, Is_Access_Constant
12518 -- The new itype needs freezing when it depends on a not frozen
12519 -- type and the enclosing subtype needs freezing.
12521 if Has_Delayed_Freeze (Constrained_Typ)
12522 and then not Is_Frozen (Constrained_Typ)
12524 Conditional_Delay (Itype, Base_Type (Old_Type));
12532 end Build_Constrained_Access_Type;
12534 ----------------------------------
12535 -- Build_Constrained_Array_Type --
12536 ----------------------------------
12538 function Build_Constrained_Array_Type
12539 (Old_Type : Entity_Id) return Entity_Id
12543 Old_Index : Node_Id;
12544 Range_Node : Node_Id;
12545 Constr_List : List_Id;
12547 Need_To_Create_Itype : Boolean := False;
12550 Old_Index := First_Index (Old_Type);
12551 while Present (Old_Index) loop
12552 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
12554 if Is_Discriminant (Lo_Expr)
12556 Is_Discriminant (Hi_Expr)
12558 Need_To_Create_Itype := True;
12561 Next_Index (Old_Index);
12564 if Need_To_Create_Itype then
12565 Constr_List := New_List;
12567 Old_Index := First_Index (Old_Type);
12568 while Present (Old_Index) loop
12569 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
12571 if Is_Discriminant (Lo_Expr) then
12572 Lo_Expr := Get_Discr_Value (Lo_Expr);
12575 if Is_Discriminant (Hi_Expr) then
12576 Hi_Expr := Get_Discr_Value (Hi_Expr);
12581 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
12583 Append (Range_Node, To => Constr_List);
12585 Next_Index (Old_Index);
12588 return Build_Subtype (Old_Type, Constr_List);
12593 end Build_Constrained_Array_Type;
12595 ------------------------------------------
12596 -- Build_Constrained_Discriminated_Type --
12597 ------------------------------------------
12599 function Build_Constrained_Discriminated_Type
12600 (Old_Type : Entity_Id) return Entity_Id
12603 Constr_List : List_Id;
12604 Old_Constraint : Elmt_Id;
12606 Need_To_Create_Itype : Boolean := False;
12609 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
12610 while Present (Old_Constraint) loop
12611 Expr := Node (Old_Constraint);
12613 if Is_Discriminant (Expr) then
12614 Need_To_Create_Itype := True;
12617 Next_Elmt (Old_Constraint);
12620 if Need_To_Create_Itype then
12621 Constr_List := New_List;
12623 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
12624 while Present (Old_Constraint) loop
12625 Expr := Node (Old_Constraint);
12627 if Is_Discriminant (Expr) then
12628 Expr := Get_Discr_Value (Expr);
12631 Append (New_Copy_Tree (Expr), To => Constr_List);
12633 Next_Elmt (Old_Constraint);
12636 return Build_Subtype (Old_Type, Constr_List);
12641 end Build_Constrained_Discriminated_Type;
12643 -------------------
12644 -- Build_Subtype --
12645 -------------------
12647 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
12649 Subtyp_Decl : Node_Id;
12650 Def_Id : Entity_Id;
12651 Btyp : Entity_Id := Base_Type (T);
12654 -- The Related_Node better be here or else we won't be able to
12655 -- attach new itypes to a node in the tree.
12657 pragma Assert (Present (Related_Node));
12659 -- If the view of the component's type is incomplete or private
12660 -- with unknown discriminants, then the constraint must be applied
12661 -- to the full type.
12663 if Has_Unknown_Discriminants (Btyp)
12664 and then Present (Underlying_Type (Btyp))
12666 Btyp := Underlying_Type (Btyp);
12670 Make_Subtype_Indication (Loc,
12671 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
12672 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
12674 Def_Id := Create_Itype (Ekind (T), Related_Node);
12677 Make_Subtype_Declaration (Loc,
12678 Defining_Identifier => Def_Id,
12679 Subtype_Indication => Indic);
12681 Set_Parent (Subtyp_Decl, Parent (Related_Node));
12683 -- Itypes must be analyzed with checks off (see package Itypes)
12685 Analyze (Subtyp_Decl, Suppress => All_Checks);
12690 ---------------------
12691 -- Get_Discr_Value --
12692 ---------------------
12694 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
12699 -- The discriminant may be declared for the type, in which case we
12700 -- find it by iterating over the list of discriminants. If the
12701 -- discriminant is inherited from a parent type, it appears as the
12702 -- corresponding discriminant of the current type. This will be the
12703 -- case when constraining an inherited component whose constraint is
12704 -- given by a discriminant of the parent.
12706 D := First_Discriminant (Typ);
12707 E := First_Elmt (Constraints);
12709 while Present (D) loop
12710 if D = Entity (Discrim)
12711 or else D = CR_Discriminant (Entity (Discrim))
12712 or else Corresponding_Discriminant (D) = Entity (Discrim)
12717 Next_Discriminant (D);
12721 -- The Corresponding_Discriminant mechanism is incomplete, because
12722 -- the correspondence between new and old discriminants is not one
12723 -- to one: one new discriminant can constrain several old ones. In
12724 -- that case, scan sequentially the stored_constraint, the list of
12725 -- discriminants of the parents, and the constraints.
12727 -- Previous code checked for the present of the Stored_Constraint
12728 -- list for the derived type, but did not use it at all. Should it
12729 -- be present when the component is a discriminated task type?
12731 if Is_Derived_Type (Typ)
12732 and then Scope (Entity (Discrim)) = Etype (Typ)
12734 D := First_Discriminant (Etype (Typ));
12735 E := First_Elmt (Constraints);
12736 while Present (D) loop
12737 if D = Entity (Discrim) then
12741 Next_Discriminant (D);
12746 -- Something is wrong if we did not find the value
12748 raise Program_Error;
12749 end Get_Discr_Value;
12751 ---------------------
12752 -- Is_Discriminant --
12753 ---------------------
12755 function Is_Discriminant (Expr : Node_Id) return Boolean is
12756 Discrim_Scope : Entity_Id;
12759 if Denotes_Discriminant (Expr) then
12760 Discrim_Scope := Scope (Entity (Expr));
12762 -- Either we have a reference to one of Typ's discriminants,
12764 pragma Assert (Discrim_Scope = Typ
12766 -- or to the discriminants of the parent type, in the case
12767 -- of a derivation of a tagged type with variants.
12769 or else Discrim_Scope = Etype (Typ)
12770 or else Full_View (Discrim_Scope) = Etype (Typ)
12772 -- or same as above for the case where the discriminants
12773 -- were declared in Typ's private view.
12775 or else (Is_Private_Type (Discrim_Scope)
12776 and then Chars (Discrim_Scope) = Chars (Typ))
12778 -- or else we are deriving from the full view and the
12779 -- discriminant is declared in the private entity.
12781 or else (Is_Private_Type (Typ)
12782 and then Chars (Discrim_Scope) = Chars (Typ))
12784 -- Or we are constrained the corresponding record of a
12785 -- synchronized type that completes a private declaration.
12787 or else (Is_Concurrent_Record_Type (Typ)
12789 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
12791 -- or we have a class-wide type, in which case make sure the
12792 -- discriminant found belongs to the root type.
12794 or else (Is_Class_Wide_Type (Typ)
12795 and then Etype (Typ) = Discrim_Scope));
12800 -- In all other cases we have something wrong
12803 end Is_Discriminant;
12805 -- Start of processing for Constrain_Component_Type
12808 if Nkind (Parent (Comp)) = N_Component_Declaration
12809 and then Comes_From_Source (Parent (Comp))
12810 and then Comes_From_Source
12811 (Subtype_Indication (Component_Definition (Parent (Comp))))
12814 (Subtype_Indication (Component_Definition (Parent (Comp))))
12816 return Compon_Type;
12818 elsif Is_Array_Type (Compon_Type) then
12819 return Build_Constrained_Array_Type (Compon_Type);
12821 elsif Has_Discriminants (Compon_Type) then
12822 return Build_Constrained_Discriminated_Type (Compon_Type);
12824 elsif Is_Access_Type (Compon_Type) then
12825 return Build_Constrained_Access_Type (Compon_Type);
12828 return Compon_Type;
12830 end Constrain_Component_Type;
12832 --------------------------
12833 -- Constrain_Concurrent --
12834 --------------------------
12836 -- For concurrent types, the associated record value type carries the same
12837 -- discriminants, so when we constrain a concurrent type, we must constrain
12838 -- the corresponding record type as well.
12840 procedure Constrain_Concurrent
12841 (Def_Id : in out Entity_Id;
12843 Related_Nod : Node_Id;
12844 Related_Id : Entity_Id;
12845 Suffix : Character)
12847 -- Retrieve Base_Type to ensure getting to the concurrent type in the
12848 -- case of a private subtype (needed when only doing semantic analysis).
12850 T_Ent : Entity_Id := Base_Type (Entity (Subtype_Mark (SI)));
12854 if Is_Access_Type (T_Ent) then
12855 T_Ent := Designated_Type (T_Ent);
12858 T_Val := Corresponding_Record_Type (T_Ent);
12860 if Present (T_Val) then
12862 if No (Def_Id) then
12863 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
12865 -- Elaborate itype now, as it may be used in a subsequent
12866 -- synchronized operation in another scope.
12868 if Nkind (Related_Nod) = N_Full_Type_Declaration then
12869 Build_Itype_Reference (Def_Id, Related_Nod);
12873 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
12875 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12876 Set_Corresponding_Record_Type (Def_Id,
12877 Constrain_Corresponding_Record (Def_Id, T_Val, Related_Nod));
12880 -- If there is no associated record, expansion is disabled and this
12881 -- is a generic context. Create a subtype in any case, so that
12882 -- semantic analysis can proceed.
12884 if No (Def_Id) then
12885 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
12888 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
12890 end Constrain_Concurrent;
12892 ------------------------------------
12893 -- Constrain_Corresponding_Record --
12894 ------------------------------------
12896 function Constrain_Corresponding_Record
12897 (Prot_Subt : Entity_Id;
12898 Corr_Rec : Entity_Id;
12899 Related_Nod : Node_Id) return Entity_Id
12901 T_Sub : constant Entity_Id :=
12902 Create_Itype (E_Record_Subtype, Related_Nod, Corr_Rec, 'C');
12905 Set_Etype (T_Sub, Corr_Rec);
12906 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
12907 Set_Is_Constrained (T_Sub, True);
12908 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
12909 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
12911 if Has_Discriminants (Prot_Subt) then -- False only if errors.
12912 Set_Discriminant_Constraint
12913 (T_Sub, Discriminant_Constraint (Prot_Subt));
12914 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
12915 Create_Constrained_Components
12916 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
12919 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
12921 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
12922 Conditional_Delay (T_Sub, Corr_Rec);
12925 -- This is a component subtype: it will be frozen in the context of
12926 -- the enclosing record's init_proc, so that discriminant references
12927 -- are resolved to discriminals. (Note: we used to skip freezing
12928 -- altogether in that case, which caused errors downstream for
12929 -- components of a bit packed array type).
12931 Set_Has_Delayed_Freeze (T_Sub);
12935 end Constrain_Corresponding_Record;
12937 -----------------------
12938 -- Constrain_Decimal --
12939 -----------------------
12941 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
12942 T : constant Entity_Id := Entity (Subtype_Mark (S));
12943 C : constant Node_Id := Constraint (S);
12944 Loc : constant Source_Ptr := Sloc (C);
12945 Range_Expr : Node_Id;
12946 Digits_Expr : Node_Id;
12951 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
12953 if Nkind (C) = N_Range_Constraint then
12954 Range_Expr := Range_Expression (C);
12955 Digits_Val := Digits_Value (T);
12958 pragma Assert (Nkind (C) = N_Digits_Constraint);
12960 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
12962 Digits_Expr := Digits_Expression (C);
12963 Analyze_And_Resolve (Digits_Expr, Any_Integer);
12965 Check_Digits_Expression (Digits_Expr);
12966 Digits_Val := Expr_Value (Digits_Expr);
12968 if Digits_Val > Digits_Value (T) then
12970 ("digits expression is incompatible with subtype", C);
12971 Digits_Val := Digits_Value (T);
12974 if Present (Range_Constraint (C)) then
12975 Range_Expr := Range_Expression (Range_Constraint (C));
12977 Range_Expr := Empty;
12981 Set_Etype (Def_Id, Base_Type (T));
12982 Set_Size_Info (Def_Id, (T));
12983 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12984 Set_Delta_Value (Def_Id, Delta_Value (T));
12985 Set_Scale_Value (Def_Id, Scale_Value (T));
12986 Set_Small_Value (Def_Id, Small_Value (T));
12987 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
12988 Set_Digits_Value (Def_Id, Digits_Val);
12990 -- Manufacture range from given digits value if no range present
12992 if No (Range_Expr) then
12993 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
12997 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
12999 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
13002 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
13003 Set_Discrete_RM_Size (Def_Id);
13005 -- Unconditionally delay the freeze, since we cannot set size
13006 -- information in all cases correctly until the freeze point.
13008 Set_Has_Delayed_Freeze (Def_Id);
13009 end Constrain_Decimal;
13011 ----------------------------------
13012 -- Constrain_Discriminated_Type --
13013 ----------------------------------
13015 procedure Constrain_Discriminated_Type
13016 (Def_Id : Entity_Id;
13018 Related_Nod : Node_Id;
13019 For_Access : Boolean := False)
13021 E : constant Entity_Id := Entity (Subtype_Mark (S));
13024 Elist : Elist_Id := New_Elmt_List;
13026 procedure Fixup_Bad_Constraint;
13027 -- This is called after finding a bad constraint, and after having
13028 -- posted an appropriate error message. The mission is to leave the
13029 -- entity T in as reasonable state as possible.
13031 --------------------------
13032 -- Fixup_Bad_Constraint --
13033 --------------------------
13035 procedure Fixup_Bad_Constraint is
13037 -- Set a reasonable Ekind for the entity. For an incomplete type,
13038 -- we can't do much, but for other types, we can set the proper
13039 -- corresponding subtype kind.
13041 if Ekind (T) = E_Incomplete_Type then
13042 Set_Ekind (Def_Id, Ekind (T));
13044 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
13047 -- Set Etype to the known type, to reduce chances of cascaded errors
13049 Set_Etype (Def_Id, E);
13050 Set_Error_Posted (Def_Id);
13051 end Fixup_Bad_Constraint;
13053 -- Start of processing for Constrain_Discriminated_Type
13056 C := Constraint (S);
13058 -- A discriminant constraint is only allowed in a subtype indication,
13059 -- after a subtype mark. This subtype mark must denote either a type
13060 -- with discriminants, or an access type whose designated type is a
13061 -- type with discriminants. A discriminant constraint specifies the
13062 -- values of these discriminants (RM 3.7.2(5)).
13064 T := Base_Type (Entity (Subtype_Mark (S)));
13066 if Is_Access_Type (T) then
13067 T := Designated_Type (T);
13070 -- In an instance it may be necessary to retrieve the full view of a
13071 -- type with unknown discriminants. In other contexts the constraint
13075 and then Is_Private_Type (T)
13076 and then Has_Unknown_Discriminants (T)
13077 and then Present (Full_View (T))
13079 T := Full_View (T);
13082 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal.
13083 -- Avoid generating an error for access-to-incomplete subtypes.
13085 if Ada_Version >= Ada_2005
13086 and then Ekind (T) = E_Incomplete_Type
13087 and then Nkind (Parent (S)) = N_Subtype_Declaration
13088 and then not Is_Itype (Def_Id)
13090 -- A little sanity check, emit an error message if the type
13091 -- has discriminants to begin with. Type T may be a regular
13092 -- incomplete type or imported via a limited with clause.
13094 if Has_Discriminants (T)
13095 or else (From_Limited_With (T)
13096 and then Present (Non_Limited_View (T))
13097 and then Nkind (Parent (Non_Limited_View (T))) =
13098 N_Full_Type_Declaration
13099 and then Present (Discriminant_Specifications
13100 (Parent (Non_Limited_View (T)))))
13103 ("(Ada 2005) incomplete subtype may not be constrained", C);
13105 Error_Msg_N ("invalid constraint: type has no discriminant", C);
13108 Fixup_Bad_Constraint;
13111 -- Check that the type has visible discriminants. The type may be
13112 -- a private type with unknown discriminants whose full view has
13113 -- discriminants which are invisible.
13115 elsif not Has_Discriminants (T)
13117 (Has_Unknown_Discriminants (T)
13118 and then Is_Private_Type (T))
13120 Error_Msg_N ("invalid constraint: type has no discriminant", C);
13121 Fixup_Bad_Constraint;
13124 elsif Is_Constrained (E)
13125 or else (Ekind (E) = E_Class_Wide_Subtype
13126 and then Present (Discriminant_Constraint (E)))
13128 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
13129 Fixup_Bad_Constraint;
13133 -- T may be an unconstrained subtype (e.g. a generic actual).
13134 -- Constraint applies to the base type.
13136 T := Base_Type (T);
13138 Elist := Build_Discriminant_Constraints (T, S);
13140 -- If the list returned was empty we had an error in building the
13141 -- discriminant constraint. We have also already signalled an error
13142 -- in the incomplete type case
13144 if Is_Empty_Elmt_List (Elist) then
13145 Fixup_Bad_Constraint;
13149 Build_Discriminated_Subtype (T, Def_Id, Elist, Related_Nod, For_Access);
13150 end Constrain_Discriminated_Type;
13152 ---------------------------
13153 -- Constrain_Enumeration --
13154 ---------------------------
13156 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
13157 T : constant Entity_Id := Entity (Subtype_Mark (S));
13158 C : constant Node_Id := Constraint (S);
13161 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13163 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
13165 Set_Etype (Def_Id, Base_Type (T));
13166 Set_Size_Info (Def_Id, (T));
13167 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13168 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13170 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13172 Set_Discrete_RM_Size (Def_Id);
13173 end Constrain_Enumeration;
13175 ----------------------
13176 -- Constrain_Float --
13177 ----------------------
13179 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
13180 T : constant Entity_Id := Entity (Subtype_Mark (S));
13186 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
13188 Set_Etype (Def_Id, Base_Type (T));
13189 Set_Size_Info (Def_Id, (T));
13190 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13192 -- Process the constraint
13194 C := Constraint (S);
13196 -- Digits constraint present
13198 if Nkind (C) = N_Digits_Constraint then
13200 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
13201 Check_Restriction (No_Obsolescent_Features, C);
13203 if Warn_On_Obsolescent_Feature then
13205 ("subtype digits constraint is an " &
13206 "obsolescent feature (RM J.3(8))?j?", C);
13209 D := Digits_Expression (C);
13210 Analyze_And_Resolve (D, Any_Integer);
13211 Check_Digits_Expression (D);
13212 Set_Digits_Value (Def_Id, Expr_Value (D));
13214 -- Check that digits value is in range. Obviously we can do this
13215 -- at compile time, but it is strictly a runtime check, and of
13216 -- course there is an ACVC test that checks this.
13218 if Digits_Value (Def_Id) > Digits_Value (T) then
13219 Error_Msg_Uint_1 := Digits_Value (T);
13220 Error_Msg_N ("??digits value is too large, maximum is ^", D);
13222 Make_Raise_Constraint_Error (Sloc (D),
13223 Reason => CE_Range_Check_Failed);
13224 Insert_Action (Declaration_Node (Def_Id), Rais);
13227 C := Range_Constraint (C);
13229 -- No digits constraint present
13232 Set_Digits_Value (Def_Id, Digits_Value (T));
13235 -- Range constraint present
13237 if Nkind (C) = N_Range_Constraint then
13238 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13240 -- No range constraint present
13243 pragma Assert (No (C));
13244 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13247 Set_Is_Constrained (Def_Id);
13248 end Constrain_Float;
13250 ---------------------
13251 -- Constrain_Index --
13252 ---------------------
13254 procedure Constrain_Index
13257 Related_Nod : Node_Id;
13258 Related_Id : Entity_Id;
13259 Suffix : Character;
13260 Suffix_Index : Nat)
13262 Def_Id : Entity_Id;
13263 R : Node_Id := Empty;
13264 T : constant Entity_Id := Etype (Index);
13268 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
13269 Set_Etype (Def_Id, Base_Type (T));
13271 if Nkind (S) = N_Range
13273 (Nkind (S) = N_Attribute_Reference
13274 and then Attribute_Name (S) = Name_Range)
13276 -- A Range attribute will be transformed into N_Range by Resolve
13282 Process_Range_Expr_In_Decl (R, T);
13284 if not Error_Posted (S)
13286 (Nkind (S) /= N_Range
13287 or else not Covers (T, (Etype (Low_Bound (S))))
13288 or else not Covers (T, (Etype (High_Bound (S)))))
13290 if Base_Type (T) /= Any_Type
13291 and then Etype (Low_Bound (S)) /= Any_Type
13292 and then Etype (High_Bound (S)) /= Any_Type
13294 Error_Msg_N ("range expected", S);
13298 elsif Nkind (S) = N_Subtype_Indication then
13300 -- The parser has verified that this is a discrete indication
13302 Resolve_Discrete_Subtype_Indication (S, T);
13303 Bad_Predicated_Subtype_Use
13304 ("subtype& has predicate, not allowed in index constraint",
13305 S, Entity (Subtype_Mark (S)));
13307 R := Range_Expression (Constraint (S));
13309 -- Capture values of bounds and generate temporaries for them if
13310 -- needed, since checks may cause duplication of the expressions
13311 -- which must not be reevaluated.
13313 -- The forced evaluation removes side effects from expressions, which
13314 -- should occur also in GNATprove mode. Otherwise, we end up with
13315 -- unexpected insertions of actions at places where this is not
13316 -- supposed to occur, e.g. on default parameters of a call.
13318 if Expander_Active or GNATprove_Mode then
13320 (Low_Bound (R), Related_Id => Def_Id, Is_Low_Bound => True);
13322 (High_Bound (R), Related_Id => Def_Id, Is_High_Bound => True);
13325 elsif Nkind (S) = N_Discriminant_Association then
13327 -- Syntactically valid in subtype indication
13329 Error_Msg_N ("invalid index constraint", S);
13330 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13333 -- Subtype_Mark case, no anonymous subtypes to construct
13338 if Is_Entity_Name (S) then
13339 if not Is_Type (Entity (S)) then
13340 Error_Msg_N ("expect subtype mark for index constraint", S);
13342 elsif Base_Type (Entity (S)) /= Base_Type (T) then
13343 Wrong_Type (S, Base_Type (T));
13345 -- Check error of subtype with predicate in index constraint
13348 Bad_Predicated_Subtype_Use
13349 ("subtype& has predicate, not allowed in index constraint",
13356 Error_Msg_N ("invalid index constraint", S);
13357 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13362 -- Complete construction of the Itype
13364 if Is_Modular_Integer_Type (T) then
13365 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13367 elsif Is_Integer_Type (T) then
13368 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13371 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13372 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13373 Set_First_Literal (Def_Id, First_Literal (T));
13376 Set_Size_Info (Def_Id, (T));
13377 Set_RM_Size (Def_Id, RM_Size (T));
13378 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13380 Set_Scalar_Range (Def_Id, R);
13382 Set_Etype (S, Def_Id);
13383 Set_Discrete_RM_Size (Def_Id);
13384 end Constrain_Index;
13386 -----------------------
13387 -- Constrain_Integer --
13388 -----------------------
13390 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
13391 T : constant Entity_Id := Entity (Subtype_Mark (S));
13392 C : constant Node_Id := Constraint (S);
13395 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13397 if Is_Modular_Integer_Type (T) then
13398 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13400 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13403 Set_Etype (Def_Id, Base_Type (T));
13404 Set_Size_Info (Def_Id, (T));
13405 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13406 Set_Discrete_RM_Size (Def_Id);
13407 end Constrain_Integer;
13409 ------------------------------
13410 -- Constrain_Ordinary_Fixed --
13411 ------------------------------
13413 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
13414 T : constant Entity_Id := Entity (Subtype_Mark (S));
13420 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
13421 Set_Etype (Def_Id, Base_Type (T));
13422 Set_Size_Info (Def_Id, (T));
13423 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13424 Set_Small_Value (Def_Id, Small_Value (T));
13426 -- Process the constraint
13428 C := Constraint (S);
13430 -- Delta constraint present
13432 if Nkind (C) = N_Delta_Constraint then
13434 Check_SPARK_05_Restriction ("delta constraint is not allowed", S);
13435 Check_Restriction (No_Obsolescent_Features, C);
13437 if Warn_On_Obsolescent_Feature then
13439 ("subtype delta constraint is an " &
13440 "obsolescent feature (RM J.3(7))?j?");
13443 D := Delta_Expression (C);
13444 Analyze_And_Resolve (D, Any_Real);
13445 Check_Delta_Expression (D);
13446 Set_Delta_Value (Def_Id, Expr_Value_R (D));
13448 -- Check that delta value is in range. Obviously we can do this
13449 -- at compile time, but it is strictly a runtime check, and of
13450 -- course there is an ACVC test that checks this.
13452 if Delta_Value (Def_Id) < Delta_Value (T) then
13453 Error_Msg_N ("??delta value is too small", D);
13455 Make_Raise_Constraint_Error (Sloc (D),
13456 Reason => CE_Range_Check_Failed);
13457 Insert_Action (Declaration_Node (Def_Id), Rais);
13460 C := Range_Constraint (C);
13462 -- No delta constraint present
13465 Set_Delta_Value (Def_Id, Delta_Value (T));
13468 -- Range constraint present
13470 if Nkind (C) = N_Range_Constraint then
13471 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13473 -- No range constraint present
13476 pragma Assert (No (C));
13477 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13480 Set_Discrete_RM_Size (Def_Id);
13482 -- Unconditionally delay the freeze, since we cannot set size
13483 -- information in all cases correctly until the freeze point.
13485 Set_Has_Delayed_Freeze (Def_Id);
13486 end Constrain_Ordinary_Fixed;
13488 -----------------------
13489 -- Contain_Interface --
13490 -----------------------
13492 function Contain_Interface
13493 (Iface : Entity_Id;
13494 Ifaces : Elist_Id) return Boolean
13496 Iface_Elmt : Elmt_Id;
13499 if Present (Ifaces) then
13500 Iface_Elmt := First_Elmt (Ifaces);
13501 while Present (Iface_Elmt) loop
13502 if Node (Iface_Elmt) = Iface then
13506 Next_Elmt (Iface_Elmt);
13511 end Contain_Interface;
13513 ---------------------------
13514 -- Convert_Scalar_Bounds --
13515 ---------------------------
13517 procedure Convert_Scalar_Bounds
13519 Parent_Type : Entity_Id;
13520 Derived_Type : Entity_Id;
13523 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
13530 -- Defend against previous errors
13532 if No (Scalar_Range (Derived_Type)) then
13533 Check_Error_Detected;
13537 Lo := Build_Scalar_Bound
13538 (Type_Low_Bound (Derived_Type),
13539 Parent_Type, Implicit_Base);
13541 Hi := Build_Scalar_Bound
13542 (Type_High_Bound (Derived_Type),
13543 Parent_Type, Implicit_Base);
13550 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
13552 Set_Parent (Rng, N);
13553 Set_Scalar_Range (Derived_Type, Rng);
13555 -- Analyze the bounds
13557 Analyze_And_Resolve (Lo, Implicit_Base);
13558 Analyze_And_Resolve (Hi, Implicit_Base);
13560 -- Analyze the range itself, except that we do not analyze it if
13561 -- the bounds are real literals, and we have a fixed-point type.
13562 -- The reason for this is that we delay setting the bounds in this
13563 -- case till we know the final Small and Size values (see circuit
13564 -- in Freeze.Freeze_Fixed_Point_Type for further details).
13566 if Is_Fixed_Point_Type (Parent_Type)
13567 and then Nkind (Lo) = N_Real_Literal
13568 and then Nkind (Hi) = N_Real_Literal
13572 -- Here we do the analysis of the range
13574 -- Note: we do this manually, since if we do a normal Analyze and
13575 -- Resolve call, there are problems with the conversions used for
13576 -- the derived type range.
13579 Set_Etype (Rng, Implicit_Base);
13580 Set_Analyzed (Rng, True);
13582 end Convert_Scalar_Bounds;
13584 -------------------
13585 -- Copy_And_Swap --
13586 -------------------
13588 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
13590 -- Initialize new full declaration entity by copying the pertinent
13591 -- fields of the corresponding private declaration entity.
13593 -- We temporarily set Ekind to a value appropriate for a type to
13594 -- avoid assert failures in Einfo from checking for setting type
13595 -- attributes on something that is not a type. Ekind (Priv) is an
13596 -- appropriate choice, since it allowed the attributes to be set
13597 -- in the first place. This Ekind value will be modified later.
13599 Set_Ekind (Full, Ekind (Priv));
13601 -- Also set Etype temporarily to Any_Type, again, in the absence
13602 -- of errors, it will be properly reset, and if there are errors,
13603 -- then we want a value of Any_Type to remain.
13605 Set_Etype (Full, Any_Type);
13607 -- Now start copying attributes
13609 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
13611 if Has_Discriminants (Full) then
13612 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
13613 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
13616 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
13617 Set_Homonym (Full, Homonym (Priv));
13618 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
13619 Set_Is_Public (Full, Is_Public (Priv));
13620 Set_Is_Pure (Full, Is_Pure (Priv));
13621 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
13622 Set_Has_Pragma_Unmodified (Full, Has_Pragma_Unmodified (Priv));
13623 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
13624 Set_Has_Pragma_Unreferenced_Objects
13625 (Full, Has_Pragma_Unreferenced_Objects
13628 Conditional_Delay (Full, Priv);
13630 if Is_Tagged_Type (Full) then
13631 Set_Direct_Primitive_Operations
13632 (Full, Direct_Primitive_Operations (Priv));
13633 Set_No_Tagged_Streams_Pragma
13634 (Full, No_Tagged_Streams_Pragma (Priv));
13636 if Is_Base_Type (Priv) then
13637 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
13641 Set_Is_Volatile (Full, Is_Volatile (Priv));
13642 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
13643 Set_Scope (Full, Scope (Priv));
13644 Set_Next_Entity (Full, Next_Entity (Priv));
13645 Set_First_Entity (Full, First_Entity (Priv));
13646 Set_Last_Entity (Full, Last_Entity (Priv));
13648 -- If access types have been recorded for later handling, keep them in
13649 -- the full view so that they get handled when the full view freeze
13650 -- node is expanded.
13652 if Present (Freeze_Node (Priv))
13653 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
13655 Ensure_Freeze_Node (Full);
13656 Set_Access_Types_To_Process
13657 (Freeze_Node (Full),
13658 Access_Types_To_Process (Freeze_Node (Priv)));
13661 -- Swap the two entities. Now Private is the full type entity and Full
13662 -- is the private one. They will be swapped back at the end of the
13663 -- private part. This swapping ensures that the entity that is visible
13664 -- in the private part is the full declaration.
13666 Exchange_Entities (Priv, Full);
13667 Append_Entity (Full, Scope (Full));
13670 -------------------------------------
13671 -- Copy_Array_Base_Type_Attributes --
13672 -------------------------------------
13674 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
13676 Set_Component_Alignment (T1, Component_Alignment (T2));
13677 Set_Component_Type (T1, Component_Type (T2));
13678 Set_Component_Size (T1, Component_Size (T2));
13679 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
13680 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
13681 Set_Has_Protected (T1, Has_Protected (T2));
13682 Set_Has_Task (T1, Has_Task (T2));
13683 Set_Is_Packed (T1, Is_Packed (T2));
13684 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
13685 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
13686 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
13687 end Copy_Array_Base_Type_Attributes;
13689 -----------------------------------
13690 -- Copy_Array_Subtype_Attributes --
13691 -----------------------------------
13693 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
13695 Set_Size_Info (T1, T2);
13697 Set_First_Index (T1, First_Index (T2));
13698 Set_Is_Aliased (T1, Is_Aliased (T2));
13699 Set_Is_Volatile (T1, Is_Volatile (T2));
13700 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
13701 Set_Is_Constrained (T1, Is_Constrained (T2));
13702 Set_Depends_On_Private (T1, Has_Private_Component (T2));
13703 Inherit_Rep_Item_Chain (T1, T2);
13704 Set_Convention (T1, Convention (T2));
13705 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
13706 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
13707 Set_Packed_Array_Impl_Type (T1, Packed_Array_Impl_Type (T2));
13708 end Copy_Array_Subtype_Attributes;
13710 -----------------------------------
13711 -- Create_Constrained_Components --
13712 -----------------------------------
13714 procedure Create_Constrained_Components
13716 Decl_Node : Node_Id;
13718 Constraints : Elist_Id)
13720 Loc : constant Source_Ptr := Sloc (Subt);
13721 Comp_List : constant Elist_Id := New_Elmt_List;
13722 Parent_Type : constant Entity_Id := Etype (Typ);
13723 Assoc_List : constant List_Id := New_List;
13724 Discr_Val : Elmt_Id;
13728 Is_Static : Boolean := True;
13730 procedure Collect_Fixed_Components (Typ : Entity_Id);
13731 -- Collect parent type components that do not appear in a variant part
13733 procedure Create_All_Components;
13734 -- Iterate over Comp_List to create the components of the subtype
13736 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
13737 -- Creates a new component from Old_Compon, copying all the fields from
13738 -- it, including its Etype, inserts the new component in the Subt entity
13739 -- chain and returns the new component.
13741 function Is_Variant_Record (T : Entity_Id) return Boolean;
13742 -- If true, and discriminants are static, collect only components from
13743 -- variants selected by discriminant values.
13745 ------------------------------
13746 -- Collect_Fixed_Components --
13747 ------------------------------
13749 procedure Collect_Fixed_Components (Typ : Entity_Id) is
13751 -- Build association list for discriminants, and find components of the
13752 -- variant part selected by the values of the discriminants.
13754 Old_C := First_Discriminant (Typ);
13755 Discr_Val := First_Elmt (Constraints);
13756 while Present (Old_C) loop
13757 Append_To (Assoc_List,
13758 Make_Component_Association (Loc,
13759 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
13760 Expression => New_Copy (Node (Discr_Val))));
13762 Next_Elmt (Discr_Val);
13763 Next_Discriminant (Old_C);
13766 -- The tag and the possible parent component are unconditionally in
13769 if Is_Tagged_Type (Typ) or else Has_Controlled_Component (Typ) then
13770 Old_C := First_Component (Typ);
13771 while Present (Old_C) loop
13772 if Nam_In (Chars (Old_C), Name_uTag, Name_uParent) then
13773 Append_Elmt (Old_C, Comp_List);
13776 Next_Component (Old_C);
13779 end Collect_Fixed_Components;
13781 ---------------------------
13782 -- Create_All_Components --
13783 ---------------------------
13785 procedure Create_All_Components is
13789 Comp := First_Elmt (Comp_List);
13790 while Present (Comp) loop
13791 Old_C := Node (Comp);
13792 New_C := Create_Component (Old_C);
13796 Constrain_Component_Type
13797 (Old_C, Subt, Decl_Node, Typ, Constraints));
13798 Set_Is_Public (New_C, Is_Public (Subt));
13802 end Create_All_Components;
13804 ----------------------
13805 -- Create_Component --
13806 ----------------------
13808 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
13809 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
13812 if Ekind (Old_Compon) = E_Discriminant
13813 and then Is_Completely_Hidden (Old_Compon)
13815 -- This is a shadow discriminant created for a discriminant of
13816 -- the parent type, which needs to be present in the subtype.
13817 -- Give the shadow discriminant an internal name that cannot
13818 -- conflict with that of visible components.
13820 Set_Chars (New_Compon, New_Internal_Name ('C'));
13823 -- Set the parent so we have a proper link for freezing etc. This is
13824 -- not a real parent pointer, since of course our parent does not own
13825 -- up to us and reference us, we are an illegitimate child of the
13826 -- original parent.
13828 Set_Parent (New_Compon, Parent (Old_Compon));
13830 -- If the old component's Esize was already determined and is a
13831 -- static value, then the new component simply inherits it. Otherwise
13832 -- the old component's size may require run-time determination, but
13833 -- the new component's size still might be statically determinable
13834 -- (if, for example it has a static constraint). In that case we want
13835 -- Layout_Type to recompute the component's size, so we reset its
13836 -- size and positional fields.
13838 if Frontend_Layout_On_Target
13839 and then not Known_Static_Esize (Old_Compon)
13841 Set_Esize (New_Compon, Uint_0);
13842 Init_Normalized_First_Bit (New_Compon);
13843 Init_Normalized_Position (New_Compon);
13844 Init_Normalized_Position_Max (New_Compon);
13847 -- We do not want this node marked as Comes_From_Source, since
13848 -- otherwise it would get first class status and a separate cross-
13849 -- reference line would be generated. Illegitimate children do not
13850 -- rate such recognition.
13852 Set_Comes_From_Source (New_Compon, False);
13854 -- But it is a real entity, and a birth certificate must be properly
13855 -- registered by entering it into the entity list.
13857 Enter_Name (New_Compon);
13860 end Create_Component;
13862 -----------------------
13863 -- Is_Variant_Record --
13864 -----------------------
13866 function Is_Variant_Record (T : Entity_Id) return Boolean is
13868 return Nkind (Parent (T)) = N_Full_Type_Declaration
13869 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
13870 and then Present (Component_List (Type_Definition (Parent (T))))
13873 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
13874 end Is_Variant_Record;
13876 -- Start of processing for Create_Constrained_Components
13879 pragma Assert (Subt /= Base_Type (Subt));
13880 pragma Assert (Typ = Base_Type (Typ));
13882 Set_First_Entity (Subt, Empty);
13883 Set_Last_Entity (Subt, Empty);
13885 -- Check whether constraint is fully static, in which case we can
13886 -- optimize the list of components.
13888 Discr_Val := First_Elmt (Constraints);
13889 while Present (Discr_Val) loop
13890 if not Is_OK_Static_Expression (Node (Discr_Val)) then
13891 Is_Static := False;
13895 Next_Elmt (Discr_Val);
13898 Set_Has_Static_Discriminants (Subt, Is_Static);
13902 -- Inherit the discriminants of the parent type
13904 Add_Discriminants : declare
13910 Old_C := First_Discriminant (Typ);
13912 while Present (Old_C) loop
13913 Num_Disc := Num_Disc + 1;
13914 New_C := Create_Component (Old_C);
13915 Set_Is_Public (New_C, Is_Public (Subt));
13916 Next_Discriminant (Old_C);
13919 -- For an untagged derived subtype, the number of discriminants may
13920 -- be smaller than the number of inherited discriminants, because
13921 -- several of them may be renamed by a single new discriminant or
13922 -- constrained. In this case, add the hidden discriminants back into
13923 -- the subtype, because they need to be present if the optimizer of
13924 -- the GCC 4.x back-end decides to break apart assignments between
13925 -- objects using the parent view into member-wise assignments.
13929 if Is_Derived_Type (Typ)
13930 and then not Is_Tagged_Type (Typ)
13932 Old_C := First_Stored_Discriminant (Typ);
13934 while Present (Old_C) loop
13935 Num_Gird := Num_Gird + 1;
13936 Next_Stored_Discriminant (Old_C);
13940 if Num_Gird > Num_Disc then
13942 -- Find out multiple uses of new discriminants, and add hidden
13943 -- components for the extra renamed discriminants. We recognize
13944 -- multiple uses through the Corresponding_Discriminant of a
13945 -- new discriminant: if it constrains several old discriminants,
13946 -- this field points to the last one in the parent type. The
13947 -- stored discriminants of the derived type have the same name
13948 -- as those of the parent.
13952 New_Discr : Entity_Id;
13953 Old_Discr : Entity_Id;
13956 Constr := First_Elmt (Stored_Constraint (Typ));
13957 Old_Discr := First_Stored_Discriminant (Typ);
13958 while Present (Constr) loop
13959 if Is_Entity_Name (Node (Constr))
13960 and then Ekind (Entity (Node (Constr))) = E_Discriminant
13962 New_Discr := Entity (Node (Constr));
13964 if Chars (Corresponding_Discriminant (New_Discr)) /=
13967 -- The new discriminant has been used to rename a
13968 -- subsequent old discriminant. Introduce a shadow
13969 -- component for the current old discriminant.
13971 New_C := Create_Component (Old_Discr);
13972 Set_Original_Record_Component (New_C, Old_Discr);
13976 -- The constraint has eliminated the old discriminant.
13977 -- Introduce a shadow component.
13979 New_C := Create_Component (Old_Discr);
13980 Set_Original_Record_Component (New_C, Old_Discr);
13983 Next_Elmt (Constr);
13984 Next_Stored_Discriminant (Old_Discr);
13988 end Add_Discriminants;
13991 and then Is_Variant_Record (Typ)
13993 Collect_Fixed_Components (Typ);
13995 Gather_Components (
13997 Component_List (Type_Definition (Parent (Typ))),
13998 Governed_By => Assoc_List,
14000 Report_Errors => Errors);
14001 pragma Assert (not Errors);
14003 Create_All_Components;
14005 -- If the subtype declaration is created for a tagged type derivation
14006 -- with constraints, we retrieve the record definition of the parent
14007 -- type to select the components of the proper variant.
14010 and then Is_Tagged_Type (Typ)
14011 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
14013 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
14014 and then Is_Variant_Record (Parent_Type)
14016 Collect_Fixed_Components (Typ);
14020 Component_List (Type_Definition (Parent (Parent_Type))),
14021 Governed_By => Assoc_List,
14023 Report_Errors => Errors);
14025 -- Note: previously there was a check at this point that no errors
14026 -- were detected. As a consequence of AI05-220 there may be an error
14027 -- if an inherited discriminant that controls a variant has a non-
14028 -- static constraint.
14030 -- If the tagged derivation has a type extension, collect all the
14031 -- new components therein.
14033 if Present (Record_Extension_Part (Type_Definition (Parent (Typ))))
14035 Old_C := First_Component (Typ);
14036 while Present (Old_C) loop
14037 if Original_Record_Component (Old_C) = Old_C
14038 and then Chars (Old_C) /= Name_uTag
14039 and then Chars (Old_C) /= Name_uParent
14041 Append_Elmt (Old_C, Comp_List);
14044 Next_Component (Old_C);
14048 Create_All_Components;
14051 -- If discriminants are not static, or if this is a multi-level type
14052 -- extension, we have to include all components of the parent type.
14054 Old_C := First_Component (Typ);
14055 while Present (Old_C) loop
14056 New_C := Create_Component (Old_C);
14060 Constrain_Component_Type
14061 (Old_C, Subt, Decl_Node, Typ, Constraints));
14062 Set_Is_Public (New_C, Is_Public (Subt));
14064 Next_Component (Old_C);
14069 end Create_Constrained_Components;
14071 ------------------------------------------
14072 -- Decimal_Fixed_Point_Type_Declaration --
14073 ------------------------------------------
14075 procedure Decimal_Fixed_Point_Type_Declaration
14079 Loc : constant Source_Ptr := Sloc (Def);
14080 Digs_Expr : constant Node_Id := Digits_Expression (Def);
14081 Delta_Expr : constant Node_Id := Delta_Expression (Def);
14082 Implicit_Base : Entity_Id;
14089 Check_SPARK_05_Restriction
14090 ("decimal fixed point type is not allowed", Def);
14091 Check_Restriction (No_Fixed_Point, Def);
14093 -- Create implicit base type
14096 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
14097 Set_Etype (Implicit_Base, Implicit_Base);
14099 -- Analyze and process delta expression
14101 Analyze_And_Resolve (Delta_Expr, Universal_Real);
14103 Check_Delta_Expression (Delta_Expr);
14104 Delta_Val := Expr_Value_R (Delta_Expr);
14106 -- Check delta is power of 10, and determine scale value from it
14112 Scale_Val := Uint_0;
14115 if Val < Ureal_1 then
14116 while Val < Ureal_1 loop
14117 Val := Val * Ureal_10;
14118 Scale_Val := Scale_Val + 1;
14121 if Scale_Val > 18 then
14122 Error_Msg_N ("scale exceeds maximum value of 18", Def);
14123 Scale_Val := UI_From_Int (+18);
14127 while Val > Ureal_1 loop
14128 Val := Val / Ureal_10;
14129 Scale_Val := Scale_Val - 1;
14132 if Scale_Val < -18 then
14133 Error_Msg_N ("scale is less than minimum value of -18", Def);
14134 Scale_Val := UI_From_Int (-18);
14138 if Val /= Ureal_1 then
14139 Error_Msg_N ("delta expression must be a power of 10", Def);
14140 Delta_Val := Ureal_10 ** (-Scale_Val);
14144 -- Set delta, scale and small (small = delta for decimal type)
14146 Set_Delta_Value (Implicit_Base, Delta_Val);
14147 Set_Scale_Value (Implicit_Base, Scale_Val);
14148 Set_Small_Value (Implicit_Base, Delta_Val);
14150 -- Analyze and process digits expression
14152 Analyze_And_Resolve (Digs_Expr, Any_Integer);
14153 Check_Digits_Expression (Digs_Expr);
14154 Digs_Val := Expr_Value (Digs_Expr);
14156 if Digs_Val > 18 then
14157 Digs_Val := UI_From_Int (+18);
14158 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
14161 Set_Digits_Value (Implicit_Base, Digs_Val);
14162 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
14164 -- Set range of base type from digits value for now. This will be
14165 -- expanded to represent the true underlying base range by Freeze.
14167 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
14169 -- Note: We leave size as zero for now, size will be set at freeze
14170 -- time. We have to do this for ordinary fixed-point, because the size
14171 -- depends on the specified small, and we might as well do the same for
14172 -- decimal fixed-point.
14174 pragma Assert (Esize (Implicit_Base) = Uint_0);
14176 -- If there are bounds given in the declaration use them as the
14177 -- bounds of the first named subtype.
14179 if Present (Real_Range_Specification (Def)) then
14181 RRS : constant Node_Id := Real_Range_Specification (Def);
14182 Low : constant Node_Id := Low_Bound (RRS);
14183 High : constant Node_Id := High_Bound (RRS);
14188 Analyze_And_Resolve (Low, Any_Real);
14189 Analyze_And_Resolve (High, Any_Real);
14190 Check_Real_Bound (Low);
14191 Check_Real_Bound (High);
14192 Low_Val := Expr_Value_R (Low);
14193 High_Val := Expr_Value_R (High);
14195 if Low_Val < (-Bound_Val) then
14197 ("range low bound too small for digits value", Low);
14198 Low_Val := -Bound_Val;
14201 if High_Val > Bound_Val then
14203 ("range high bound too large for digits value", High);
14204 High_Val := Bound_Val;
14207 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
14210 -- If no explicit range, use range that corresponds to given
14211 -- digits value. This will end up as the final range for the
14215 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
14218 -- Complete entity for first subtype. The inheritance of the rep item
14219 -- chain ensures that SPARK-related pragmas are not clobbered when the
14220 -- decimal fixed point type acts as a full view of a private type.
14222 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
14223 Set_Etype (T, Implicit_Base);
14224 Set_Size_Info (T, Implicit_Base);
14225 Inherit_Rep_Item_Chain (T, Implicit_Base);
14226 Set_Digits_Value (T, Digs_Val);
14227 Set_Delta_Value (T, Delta_Val);
14228 Set_Small_Value (T, Delta_Val);
14229 Set_Scale_Value (T, Scale_Val);
14230 Set_Is_Constrained (T);
14231 end Decimal_Fixed_Point_Type_Declaration;
14233 -----------------------------------
14234 -- Derive_Progenitor_Subprograms --
14235 -----------------------------------
14237 procedure Derive_Progenitor_Subprograms
14238 (Parent_Type : Entity_Id;
14239 Tagged_Type : Entity_Id)
14244 Iface_Elmt : Elmt_Id;
14245 Iface_Subp : Entity_Id;
14246 New_Subp : Entity_Id := Empty;
14247 Prim_Elmt : Elmt_Id;
14252 pragma Assert (Ada_Version >= Ada_2005
14253 and then Is_Record_Type (Tagged_Type)
14254 and then Is_Tagged_Type (Tagged_Type)
14255 and then Has_Interfaces (Tagged_Type));
14257 -- Step 1: Transfer to the full-view primitives associated with the
14258 -- partial-view that cover interface primitives. Conceptually this
14259 -- work should be done later by Process_Full_View; done here to
14260 -- simplify its implementation at later stages. It can be safely
14261 -- done here because interfaces must be visible in the partial and
14262 -- private view (RM 7.3(7.3/2)).
14264 -- Small optimization: This work is only required if the parent may
14265 -- have entities whose Alias attribute reference an interface primitive.
14266 -- Such a situation may occur if the parent is an abstract type and the
14267 -- primitive has not been yet overridden or if the parent is a generic
14268 -- formal type covering interfaces.
14270 -- If the tagged type is not abstract, it cannot have abstract
14271 -- primitives (the only entities in the list of primitives of
14272 -- non-abstract tagged types that can reference abstract primitives
14273 -- through its Alias attribute are the internal entities that have
14274 -- attribute Interface_Alias, and these entities are generated later
14275 -- by Add_Internal_Interface_Entities).
14277 if In_Private_Part (Current_Scope)
14278 and then (Is_Abstract_Type (Parent_Type)
14280 Is_Generic_Type (Parent_Type))
14282 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
14283 while Present (Elmt) loop
14284 Subp := Node (Elmt);
14286 -- At this stage it is not possible to have entities in the list
14287 -- of primitives that have attribute Interface_Alias.
14289 pragma Assert (No (Interface_Alias (Subp)));
14291 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
14293 if Is_Interface (Typ) then
14294 E := Find_Primitive_Covering_Interface
14295 (Tagged_Type => Tagged_Type,
14296 Iface_Prim => Subp);
14299 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
14301 Replace_Elmt (Elmt, E);
14302 Remove_Homonym (Subp);
14310 -- Step 2: Add primitives of progenitors that are not implemented by
14311 -- parents of Tagged_Type.
14313 if Present (Interfaces (Base_Type (Tagged_Type))) then
14314 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
14315 while Present (Iface_Elmt) loop
14316 Iface := Node (Iface_Elmt);
14318 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
14319 while Present (Prim_Elmt) loop
14320 Iface_Subp := Node (Prim_Elmt);
14322 -- Exclude derivation of predefined primitives except those
14323 -- that come from source, or are inherited from one that comes
14324 -- from source. Required to catch declarations of equality
14325 -- operators of interfaces. For example:
14327 -- type Iface is interface;
14328 -- function "=" (Left, Right : Iface) return Boolean;
14330 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
14331 or else Comes_From_Source (Ultimate_Alias (Iface_Subp))
14333 E := Find_Primitive_Covering_Interface
14334 (Tagged_Type => Tagged_Type,
14335 Iface_Prim => Iface_Subp);
14337 -- If not found we derive a new primitive leaving its alias
14338 -- attribute referencing the interface primitive.
14342 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14344 -- Ada 2012 (AI05-0197): If the covering primitive's name
14345 -- differs from the name of the interface primitive then it
14346 -- is a private primitive inherited from a parent type. In
14347 -- such case, given that Tagged_Type covers the interface,
14348 -- the inherited private primitive becomes visible. For such
14349 -- purpose we add a new entity that renames the inherited
14350 -- private primitive.
14352 elsif Chars (E) /= Chars (Iface_Subp) then
14353 pragma Assert (Has_Suffix (E, 'P'));
14355 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14356 Set_Alias (New_Subp, E);
14357 Set_Is_Abstract_Subprogram (New_Subp,
14358 Is_Abstract_Subprogram (E));
14360 -- Propagate to the full view interface entities associated
14361 -- with the partial view.
14363 elsif In_Private_Part (Current_Scope)
14364 and then Present (Alias (E))
14365 and then Alias (E) = Iface_Subp
14367 List_Containing (Parent (E)) /=
14368 Private_Declarations
14370 (Unit_Declaration_Node (Current_Scope)))
14372 Append_Elmt (E, Primitive_Operations (Tagged_Type));
14376 Next_Elmt (Prim_Elmt);
14379 Next_Elmt (Iface_Elmt);
14382 end Derive_Progenitor_Subprograms;
14384 -----------------------
14385 -- Derive_Subprogram --
14386 -----------------------
14388 procedure Derive_Subprogram
14389 (New_Subp : in out Entity_Id;
14390 Parent_Subp : Entity_Id;
14391 Derived_Type : Entity_Id;
14392 Parent_Type : Entity_Id;
14393 Actual_Subp : Entity_Id := Empty)
14395 Formal : Entity_Id;
14396 -- Formal parameter of parent primitive operation
14398 Formal_Of_Actual : Entity_Id;
14399 -- Formal parameter of actual operation, when the derivation is to
14400 -- create a renaming for a primitive operation of an actual in an
14403 New_Formal : Entity_Id;
14404 -- Formal of inherited operation
14406 Visible_Subp : Entity_Id := Parent_Subp;
14408 function Is_Private_Overriding return Boolean;
14409 -- If Subp is a private overriding of a visible operation, the inherited
14410 -- operation derives from the overridden op (even though its body is the
14411 -- overriding one) and the inherited operation is visible now. See
14412 -- sem_disp to see the full details of the handling of the overridden
14413 -- subprogram, which is removed from the list of primitive operations of
14414 -- the type. The overridden subprogram is saved locally in Visible_Subp,
14415 -- and used to diagnose abstract operations that need overriding in the
14418 procedure Replace_Type (Id, New_Id : Entity_Id);
14419 -- When the type is an anonymous access type, create a new access type
14420 -- designating the derived type.
14422 procedure Set_Derived_Name;
14423 -- This procedure sets the appropriate Chars name for New_Subp. This
14424 -- is normally just a copy of the parent name. An exception arises for
14425 -- type support subprograms, where the name is changed to reflect the
14426 -- name of the derived type, e.g. if type foo is derived from type bar,
14427 -- then a procedure barDA is derived with a name fooDA.
14429 ---------------------------
14430 -- Is_Private_Overriding --
14431 ---------------------------
14433 function Is_Private_Overriding return Boolean is
14437 -- If the parent is not a dispatching operation there is no
14438 -- need to investigate overridings
14440 if not Is_Dispatching_Operation (Parent_Subp) then
14444 -- The visible operation that is overridden is a homonym of the
14445 -- parent subprogram. We scan the homonym chain to find the one
14446 -- whose alias is the subprogram we are deriving.
14448 Prev := Current_Entity (Parent_Subp);
14449 while Present (Prev) loop
14450 if Ekind (Prev) = Ekind (Parent_Subp)
14451 and then Alias (Prev) = Parent_Subp
14452 and then Scope (Parent_Subp) = Scope (Prev)
14453 and then not Is_Hidden (Prev)
14455 Visible_Subp := Prev;
14459 Prev := Homonym (Prev);
14463 end Is_Private_Overriding;
14469 procedure Replace_Type (Id, New_Id : Entity_Id) is
14470 Id_Type : constant Entity_Id := Etype (Id);
14471 Acc_Type : Entity_Id;
14472 Par : constant Node_Id := Parent (Derived_Type);
14475 -- When the type is an anonymous access type, create a new access
14476 -- type designating the derived type. This itype must be elaborated
14477 -- at the point of the derivation, not on subsequent calls that may
14478 -- be out of the proper scope for Gigi, so we insert a reference to
14479 -- it after the derivation.
14481 if Ekind (Id_Type) = E_Anonymous_Access_Type then
14483 Desig_Typ : Entity_Id := Designated_Type (Id_Type);
14486 if Ekind (Desig_Typ) = E_Record_Type_With_Private
14487 and then Present (Full_View (Desig_Typ))
14488 and then not Is_Private_Type (Parent_Type)
14490 Desig_Typ := Full_View (Desig_Typ);
14493 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
14495 -- Ada 2005 (AI-251): Handle also derivations of abstract
14496 -- interface primitives.
14498 or else (Is_Interface (Desig_Typ)
14499 and then not Is_Class_Wide_Type (Desig_Typ))
14501 Acc_Type := New_Copy (Id_Type);
14502 Set_Etype (Acc_Type, Acc_Type);
14503 Set_Scope (Acc_Type, New_Subp);
14505 -- Set size of anonymous access type. If we have an access
14506 -- to an unconstrained array, this is a fat pointer, so it
14507 -- is sizes at twice addtress size.
14509 if Is_Array_Type (Desig_Typ)
14510 and then not Is_Constrained (Desig_Typ)
14512 Init_Size (Acc_Type, 2 * System_Address_Size);
14514 -- Other cases use a thin pointer
14517 Init_Size (Acc_Type, System_Address_Size);
14520 -- Set remaining characterstics of anonymous access type
14522 Init_Alignment (Acc_Type);
14523 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
14525 Set_Etype (New_Id, Acc_Type);
14526 Set_Scope (New_Id, New_Subp);
14528 -- Create a reference to it
14530 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
14533 Set_Etype (New_Id, Id_Type);
14537 -- In Ada2012, a formal may have an incomplete type but the type
14538 -- derivation that inherits the primitive follows the full view.
14540 elsif Base_Type (Id_Type) = Base_Type (Parent_Type)
14542 (Ekind (Id_Type) = E_Record_Type_With_Private
14543 and then Present (Full_View (Id_Type))
14545 Base_Type (Full_View (Id_Type)) = Base_Type (Parent_Type))
14547 (Ada_Version >= Ada_2012
14548 and then Ekind (Id_Type) = E_Incomplete_Type
14549 and then Full_View (Id_Type) = Parent_Type)
14551 -- Constraint checks on formals are generated during expansion,
14552 -- based on the signature of the original subprogram. The bounds
14553 -- of the derived type are not relevant, and thus we can use
14554 -- the base type for the formals. However, the return type may be
14555 -- used in a context that requires that the proper static bounds
14556 -- be used (a case statement, for example) and for those cases
14557 -- we must use the derived type (first subtype), not its base.
14559 -- If the derived_type_definition has no constraints, we know that
14560 -- the derived type has the same constraints as the first subtype
14561 -- of the parent, and we can also use it rather than its base,
14562 -- which can lead to more efficient code.
14564 if Etype (Id) = Parent_Type then
14565 if Is_Scalar_Type (Parent_Type)
14567 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
14569 Set_Etype (New_Id, Derived_Type);
14571 elsif Nkind (Par) = N_Full_Type_Declaration
14573 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
14576 (Subtype_Indication (Type_Definition (Par)))
14578 Set_Etype (New_Id, Derived_Type);
14581 Set_Etype (New_Id, Base_Type (Derived_Type));
14585 Set_Etype (New_Id, Base_Type (Derived_Type));
14589 Set_Etype (New_Id, Etype (Id));
14593 ----------------------
14594 -- Set_Derived_Name --
14595 ----------------------
14597 procedure Set_Derived_Name is
14598 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
14600 if Nm = TSS_Null then
14601 Set_Chars (New_Subp, Chars (Parent_Subp));
14603 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
14605 end Set_Derived_Name;
14607 -- Start of processing for Derive_Subprogram
14610 New_Subp := New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
14611 Set_Ekind (New_Subp, Ekind (Parent_Subp));
14613 -- Check whether the inherited subprogram is a private operation that
14614 -- should be inherited but not yet made visible. Such subprograms can
14615 -- become visible at a later point (e.g., the private part of a public
14616 -- child unit) via Declare_Inherited_Private_Subprograms. If the
14617 -- following predicate is true, then this is not such a private
14618 -- operation and the subprogram simply inherits the name of the parent
14619 -- subprogram. Note the special check for the names of controlled
14620 -- operations, which are currently exempted from being inherited with
14621 -- a hidden name because they must be findable for generation of
14622 -- implicit run-time calls.
14624 if not Is_Hidden (Parent_Subp)
14625 or else Is_Internal (Parent_Subp)
14626 or else Is_Private_Overriding
14627 or else Is_Internal_Name (Chars (Parent_Subp))
14628 or else Nam_In (Chars (Parent_Subp), Name_Initialize,
14634 -- An inherited dispatching equality will be overridden by an internally
14635 -- generated one, or by an explicit one, so preserve its name and thus
14636 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
14637 -- private operation it may become invisible if the full view has
14638 -- progenitors, and the dispatch table will be malformed.
14639 -- We check that the type is limited to handle the anomalous declaration
14640 -- of Limited_Controlled, which is derived from a non-limited type, and
14641 -- which is handled specially elsewhere as well.
14643 elsif Chars (Parent_Subp) = Name_Op_Eq
14644 and then Is_Dispatching_Operation (Parent_Subp)
14645 and then Etype (Parent_Subp) = Standard_Boolean
14646 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
14648 Etype (First_Formal (Parent_Subp)) =
14649 Etype (Next_Formal (First_Formal (Parent_Subp)))
14653 -- If parent is hidden, this can be a regular derivation if the
14654 -- parent is immediately visible in a non-instantiating context,
14655 -- or if we are in the private part of an instance. This test
14656 -- should still be refined ???
14658 -- The test for In_Instance_Not_Visible avoids inheriting the derived
14659 -- operation as a non-visible operation in cases where the parent
14660 -- subprogram might not be visible now, but was visible within the
14661 -- original generic, so it would be wrong to make the inherited
14662 -- subprogram non-visible now. (Not clear if this test is fully
14663 -- correct; are there any cases where we should declare the inherited
14664 -- operation as not visible to avoid it being overridden, e.g., when
14665 -- the parent type is a generic actual with private primitives ???)
14667 -- (they should be treated the same as other private inherited
14668 -- subprograms, but it's not clear how to do this cleanly). ???
14670 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
14671 and then Is_Immediately_Visible (Parent_Subp)
14672 and then not In_Instance)
14673 or else In_Instance_Not_Visible
14677 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
14678 -- overrides an interface primitive because interface primitives
14679 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
14681 elsif Ada_Version >= Ada_2005
14682 and then Is_Dispatching_Operation (Parent_Subp)
14683 and then Covers_Some_Interface (Parent_Subp)
14687 -- Otherwise, the type is inheriting a private operation, so enter it
14688 -- with a special name so it can't be overridden.
14691 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
14694 Set_Parent (New_Subp, Parent (Derived_Type));
14696 if Present (Actual_Subp) then
14697 Replace_Type (Actual_Subp, New_Subp);
14699 Replace_Type (Parent_Subp, New_Subp);
14702 Conditional_Delay (New_Subp, Parent_Subp);
14704 -- If we are creating a renaming for a primitive operation of an
14705 -- actual of a generic derived type, we must examine the signature
14706 -- of the actual primitive, not that of the generic formal, which for
14707 -- example may be an interface. However the name and initial value
14708 -- of the inherited operation are those of the formal primitive.
14710 Formal := First_Formal (Parent_Subp);
14712 if Present (Actual_Subp) then
14713 Formal_Of_Actual := First_Formal (Actual_Subp);
14715 Formal_Of_Actual := Empty;
14718 while Present (Formal) loop
14719 New_Formal := New_Copy (Formal);
14721 -- Normally we do not go copying parents, but in the case of
14722 -- formals, we need to link up to the declaration (which is the
14723 -- parameter specification), and it is fine to link up to the
14724 -- original formal's parameter specification in this case.
14726 Set_Parent (New_Formal, Parent (Formal));
14727 Append_Entity (New_Formal, New_Subp);
14729 if Present (Formal_Of_Actual) then
14730 Replace_Type (Formal_Of_Actual, New_Formal);
14731 Next_Formal (Formal_Of_Actual);
14733 Replace_Type (Formal, New_Formal);
14736 Next_Formal (Formal);
14739 -- If this derivation corresponds to a tagged generic actual, then
14740 -- primitive operations rename those of the actual. Otherwise the
14741 -- primitive operations rename those of the parent type, If the parent
14742 -- renames an intrinsic operator, so does the new subprogram. We except
14743 -- concatenation, which is always properly typed, and does not get
14744 -- expanded as other intrinsic operations.
14746 if No (Actual_Subp) then
14747 if Is_Intrinsic_Subprogram (Parent_Subp) then
14748 Set_Is_Intrinsic_Subprogram (New_Subp);
14750 if Present (Alias (Parent_Subp))
14751 and then Chars (Parent_Subp) /= Name_Op_Concat
14753 Set_Alias (New_Subp, Alias (Parent_Subp));
14755 Set_Alias (New_Subp, Parent_Subp);
14759 Set_Alias (New_Subp, Parent_Subp);
14763 Set_Alias (New_Subp, Actual_Subp);
14766 -- Inherit the "ghostness" from the parent subprogram
14768 if Is_Ghost_Entity (Alias (New_Subp)) then
14769 Set_Is_Ghost_Entity (New_Subp);
14772 -- Derived subprograms of a tagged type must inherit the convention
14773 -- of the parent subprogram (a requirement of AI-117). Derived
14774 -- subprograms of untagged types simply get convention Ada by default.
14776 -- If the derived type is a tagged generic formal type with unknown
14777 -- discriminants, its convention is intrinsic (RM 6.3.1 (8)).
14779 -- However, if the type is derived from a generic formal, the further
14780 -- inherited subprogram has the convention of the non-generic ancestor.
14781 -- Otherwise there would be no way to override the operation.
14782 -- (This is subject to forthcoming ARG discussions).
14784 if Is_Tagged_Type (Derived_Type) then
14785 if Is_Generic_Type (Derived_Type)
14786 and then Has_Unknown_Discriminants (Derived_Type)
14788 Set_Convention (New_Subp, Convention_Intrinsic);
14791 if Is_Generic_Type (Parent_Type)
14792 and then Has_Unknown_Discriminants (Parent_Type)
14794 Set_Convention (New_Subp, Convention (Alias (Parent_Subp)));
14796 Set_Convention (New_Subp, Convention (Parent_Subp));
14801 -- Predefined controlled operations retain their name even if the parent
14802 -- is hidden (see above), but they are not primitive operations if the
14803 -- ancestor is not visible, for example if the parent is a private
14804 -- extension completed with a controlled extension. Note that a full
14805 -- type that is controlled can break privacy: the flag Is_Controlled is
14806 -- set on both views of the type.
14808 if Is_Controlled (Parent_Type)
14809 and then Nam_In (Chars (Parent_Subp), Name_Initialize,
14812 and then Is_Hidden (Parent_Subp)
14813 and then not Is_Visibly_Controlled (Parent_Type)
14815 Set_Is_Hidden (New_Subp);
14818 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
14819 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
14821 if Ekind (Parent_Subp) = E_Procedure then
14822 Set_Is_Valued_Procedure
14823 (New_Subp, Is_Valued_Procedure (Parent_Subp));
14825 Set_Has_Controlling_Result
14826 (New_Subp, Has_Controlling_Result (Parent_Subp));
14829 -- No_Return must be inherited properly. If this is overridden in the
14830 -- case of a dispatching operation, then a check is made in Sem_Disp
14831 -- that the overriding operation is also No_Return (no such check is
14832 -- required for the case of non-dispatching operation.
14834 Set_No_Return (New_Subp, No_Return (Parent_Subp));
14836 -- A derived function with a controlling result is abstract. If the
14837 -- Derived_Type is a nonabstract formal generic derived type, then
14838 -- inherited operations are not abstract: the required check is done at
14839 -- instantiation time. If the derivation is for a generic actual, the
14840 -- function is not abstract unless the actual is.
14842 if Is_Generic_Type (Derived_Type)
14843 and then not Is_Abstract_Type (Derived_Type)
14847 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
14848 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
14850 -- A subprogram subject to pragma Extensions_Visible with value False
14851 -- requires overriding if the subprogram has at least one controlling
14852 -- OUT parameter (SPARK RM 6.1.7(6)).
14854 elsif Ada_Version >= Ada_2005
14855 and then (Is_Abstract_Subprogram (Alias (New_Subp))
14856 or else (Is_Tagged_Type (Derived_Type)
14857 and then Etype (New_Subp) = Derived_Type
14858 and then not Is_Null_Extension (Derived_Type))
14859 or else (Is_Tagged_Type (Derived_Type)
14860 and then Ekind (Etype (New_Subp)) =
14861 E_Anonymous_Access_Type
14862 and then Designated_Type (Etype (New_Subp)) =
14864 and then not Is_Null_Extension (Derived_Type))
14865 or else (Comes_From_Source (Alias (New_Subp))
14866 and then Is_EVF_Procedure (Alias (New_Subp))))
14867 and then No (Actual_Subp)
14869 if not Is_Tagged_Type (Derived_Type)
14870 or else Is_Abstract_Type (Derived_Type)
14871 or else Is_Abstract_Subprogram (Alias (New_Subp))
14873 Set_Is_Abstract_Subprogram (New_Subp);
14875 Set_Requires_Overriding (New_Subp);
14878 elsif Ada_Version < Ada_2005
14879 and then (Is_Abstract_Subprogram (Alias (New_Subp))
14880 or else (Is_Tagged_Type (Derived_Type)
14881 and then Etype (New_Subp) = Derived_Type
14882 and then No (Actual_Subp)))
14884 Set_Is_Abstract_Subprogram (New_Subp);
14886 -- AI05-0097 : an inherited operation that dispatches on result is
14887 -- abstract if the derived type is abstract, even if the parent type
14888 -- is concrete and the derived type is a null extension.
14890 elsif Has_Controlling_Result (Alias (New_Subp))
14891 and then Is_Abstract_Type (Etype (New_Subp))
14893 Set_Is_Abstract_Subprogram (New_Subp);
14895 -- Finally, if the parent type is abstract we must verify that all
14896 -- inherited operations are either non-abstract or overridden, or that
14897 -- the derived type itself is abstract (this check is performed at the
14898 -- end of a package declaration, in Check_Abstract_Overriding). A
14899 -- private overriding in the parent type will not be visible in the
14900 -- derivation if we are not in an inner package or in a child unit of
14901 -- the parent type, in which case the abstractness of the inherited
14902 -- operation is carried to the new subprogram.
14904 elsif Is_Abstract_Type (Parent_Type)
14905 and then not In_Open_Scopes (Scope (Parent_Type))
14906 and then Is_Private_Overriding
14907 and then Is_Abstract_Subprogram (Visible_Subp)
14909 if No (Actual_Subp) then
14910 Set_Alias (New_Subp, Visible_Subp);
14911 Set_Is_Abstract_Subprogram (New_Subp, True);
14914 -- If this is a derivation for an instance of a formal derived
14915 -- type, abstractness comes from the primitive operation of the
14916 -- actual, not from the operation inherited from the ancestor.
14918 Set_Is_Abstract_Subprogram
14919 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
14923 New_Overloaded_Entity (New_Subp, Derived_Type);
14925 -- Check for case of a derived subprogram for the instantiation of a
14926 -- formal derived tagged type, if so mark the subprogram as dispatching
14927 -- and inherit the dispatching attributes of the actual subprogram. The
14928 -- derived subprogram is effectively renaming of the actual subprogram,
14929 -- so it needs to have the same attributes as the actual.
14931 if Present (Actual_Subp)
14932 and then Is_Dispatching_Operation (Actual_Subp)
14934 Set_Is_Dispatching_Operation (New_Subp);
14936 if Present (DTC_Entity (Actual_Subp)) then
14937 Set_DTC_Entity (New_Subp, DTC_Entity (Actual_Subp));
14938 Set_DT_Position_Value (New_Subp, DT_Position (Actual_Subp));
14942 -- Indicate that a derived subprogram does not require a body and that
14943 -- it does not require processing of default expressions.
14945 Set_Has_Completion (New_Subp);
14946 Set_Default_Expressions_Processed (New_Subp);
14948 if Ekind (New_Subp) = E_Function then
14949 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
14951 end Derive_Subprogram;
14953 ------------------------
14954 -- Derive_Subprograms --
14955 ------------------------
14957 procedure Derive_Subprograms
14958 (Parent_Type : Entity_Id;
14959 Derived_Type : Entity_Id;
14960 Generic_Actual : Entity_Id := Empty)
14962 Op_List : constant Elist_Id :=
14963 Collect_Primitive_Operations (Parent_Type);
14965 function Check_Derived_Type return Boolean;
14966 -- Check that all the entities derived from Parent_Type are found in
14967 -- the list of primitives of Derived_Type exactly in the same order.
14969 procedure Derive_Interface_Subprogram
14970 (New_Subp : in out Entity_Id;
14972 Actual_Subp : Entity_Id);
14973 -- Derive New_Subp from the ultimate alias of the parent subprogram Subp
14974 -- (which is an interface primitive). If Generic_Actual is present then
14975 -- Actual_Subp is the actual subprogram corresponding with the generic
14976 -- subprogram Subp.
14978 function Check_Derived_Type return Boolean is
14982 New_Subp : Entity_Id;
14987 -- Traverse list of entities in the current scope searching for
14988 -- an incomplete type whose full-view is derived type
14990 E := First_Entity (Scope (Derived_Type));
14991 while Present (E) and then E /= Derived_Type loop
14992 if Ekind (E) = E_Incomplete_Type
14993 and then Present (Full_View (E))
14994 and then Full_View (E) = Derived_Type
14996 -- Disable this test if Derived_Type completes an incomplete
14997 -- type because in such case more primitives can be added
14998 -- later to the list of primitives of Derived_Type by routine
14999 -- Process_Incomplete_Dependents
15004 E := Next_Entity (E);
15007 List := Collect_Primitive_Operations (Derived_Type);
15008 Elmt := First_Elmt (List);
15010 Op_Elmt := First_Elmt (Op_List);
15011 while Present (Op_Elmt) loop
15012 Subp := Node (Op_Elmt);
15013 New_Subp := Node (Elmt);
15015 -- At this early stage Derived_Type has no entities with attribute
15016 -- Interface_Alias. In addition, such primitives are always
15017 -- located at the end of the list of primitives of Parent_Type.
15018 -- Therefore, if found we can safely stop processing pending
15021 exit when Present (Interface_Alias (Subp));
15023 -- Handle hidden entities
15025 if not Is_Predefined_Dispatching_Operation (Subp)
15026 and then Is_Hidden (Subp)
15028 if Present (New_Subp)
15029 and then Primitive_Names_Match (Subp, New_Subp)
15035 if not Present (New_Subp)
15036 or else Ekind (Subp) /= Ekind (New_Subp)
15037 or else not Primitive_Names_Match (Subp, New_Subp)
15045 Next_Elmt (Op_Elmt);
15049 end Check_Derived_Type;
15051 ---------------------------------
15052 -- Derive_Interface_Subprogram --
15053 ---------------------------------
15055 procedure Derive_Interface_Subprogram
15056 (New_Subp : in out Entity_Id;
15058 Actual_Subp : Entity_Id)
15060 Iface_Subp : constant Entity_Id := Ultimate_Alias (Subp);
15061 Iface_Type : constant Entity_Id := Find_Dispatching_Type (Iface_Subp);
15064 pragma Assert (Is_Interface (Iface_Type));
15067 (New_Subp => New_Subp,
15068 Parent_Subp => Iface_Subp,
15069 Derived_Type => Derived_Type,
15070 Parent_Type => Iface_Type,
15071 Actual_Subp => Actual_Subp);
15073 -- Given that this new interface entity corresponds with a primitive
15074 -- of the parent that was not overridden we must leave it associated
15075 -- with its parent primitive to ensure that it will share the same
15076 -- dispatch table slot when overridden. We must set the Alias to Subp
15077 -- (instead of Iface_Subp), and we must fix Is_Abstract_Subprogram
15078 -- (in case we inherited Subp from Iface_Type via a nonabstract
15079 -- generic formal type).
15081 if No (Actual_Subp) then
15082 Set_Alias (New_Subp, Subp);
15085 T : Entity_Id := Find_Dispatching_Type (Subp);
15087 while Etype (T) /= T loop
15088 if Is_Generic_Type (T) and then not Is_Abstract_Type (T) then
15089 Set_Is_Abstract_Subprogram (New_Subp, False);
15097 -- For instantiations this is not needed since the previous call to
15098 -- Derive_Subprogram leaves the entity well decorated.
15101 pragma Assert (Alias (New_Subp) = Actual_Subp);
15104 end Derive_Interface_Subprogram;
15108 Alias_Subp : Entity_Id;
15109 Act_List : Elist_Id;
15110 Act_Elmt : Elmt_Id;
15111 Act_Subp : Entity_Id := Empty;
15113 Need_Search : Boolean := False;
15114 New_Subp : Entity_Id := Empty;
15115 Parent_Base : Entity_Id;
15118 -- Start of processing for Derive_Subprograms
15121 if Ekind (Parent_Type) = E_Record_Type_With_Private
15122 and then Has_Discriminants (Parent_Type)
15123 and then Present (Full_View (Parent_Type))
15125 Parent_Base := Full_View (Parent_Type);
15127 Parent_Base := Parent_Type;
15130 if Present (Generic_Actual) then
15131 Act_List := Collect_Primitive_Operations (Generic_Actual);
15132 Act_Elmt := First_Elmt (Act_List);
15134 Act_List := No_Elist;
15135 Act_Elmt := No_Elmt;
15138 -- Derive primitives inherited from the parent. Note that if the generic
15139 -- actual is present, this is not really a type derivation, it is a
15140 -- completion within an instance.
15142 -- Case 1: Derived_Type does not implement interfaces
15144 if not Is_Tagged_Type (Derived_Type)
15145 or else (not Has_Interfaces (Derived_Type)
15146 and then not (Present (Generic_Actual)
15147 and then Has_Interfaces (Generic_Actual)))
15149 Elmt := First_Elmt (Op_List);
15150 while Present (Elmt) loop
15151 Subp := Node (Elmt);
15153 -- Literals are derived earlier in the process of building the
15154 -- derived type, and are skipped here.
15156 if Ekind (Subp) = E_Enumeration_Literal then
15159 -- The actual is a direct descendant and the common primitive
15160 -- operations appear in the same order.
15162 -- If the generic parent type is present, the derived type is an
15163 -- instance of a formal derived type, and within the instance its
15164 -- operations are those of the actual. We derive from the formal
15165 -- type but make the inherited operations aliases of the
15166 -- corresponding operations of the actual.
15169 pragma Assert (No (Node (Act_Elmt))
15170 or else (Primitive_Names_Match (Subp, Node (Act_Elmt))
15173 (Subp, Node (Act_Elmt),
15174 Skip_Controlling_Formals => True)));
15177 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
15179 if Present (Act_Elmt) then
15180 Next_Elmt (Act_Elmt);
15187 -- Case 2: Derived_Type implements interfaces
15190 -- If the parent type has no predefined primitives we remove
15191 -- predefined primitives from the list of primitives of generic
15192 -- actual to simplify the complexity of this algorithm.
15194 if Present (Generic_Actual) then
15196 Has_Predefined_Primitives : Boolean := False;
15199 -- Check if the parent type has predefined primitives
15201 Elmt := First_Elmt (Op_List);
15202 while Present (Elmt) loop
15203 Subp := Node (Elmt);
15205 if Is_Predefined_Dispatching_Operation (Subp)
15206 and then not Comes_From_Source (Ultimate_Alias (Subp))
15208 Has_Predefined_Primitives := True;
15215 -- Remove predefined primitives of Generic_Actual. We must use
15216 -- an auxiliary list because in case of tagged types the value
15217 -- returned by Collect_Primitive_Operations is the value stored
15218 -- in its Primitive_Operations attribute (and we don't want to
15219 -- modify its current contents).
15221 if not Has_Predefined_Primitives then
15223 Aux_List : constant Elist_Id := New_Elmt_List;
15226 Elmt := First_Elmt (Act_List);
15227 while Present (Elmt) loop
15228 Subp := Node (Elmt);
15230 if not Is_Predefined_Dispatching_Operation (Subp)
15231 or else Comes_From_Source (Subp)
15233 Append_Elmt (Subp, Aux_List);
15239 Act_List := Aux_List;
15243 Act_Elmt := First_Elmt (Act_List);
15244 Act_Subp := Node (Act_Elmt);
15248 -- Stage 1: If the generic actual is not present we derive the
15249 -- primitives inherited from the parent type. If the generic parent
15250 -- type is present, the derived type is an instance of a formal
15251 -- derived type, and within the instance its operations are those of
15252 -- the actual. We derive from the formal type but make the inherited
15253 -- operations aliases of the corresponding operations of the actual.
15255 Elmt := First_Elmt (Op_List);
15256 while Present (Elmt) loop
15257 Subp := Node (Elmt);
15258 Alias_Subp := Ultimate_Alias (Subp);
15260 -- Do not derive internal entities of the parent that link
15261 -- interface primitives with their covering primitive. These
15262 -- entities will be added to this type when frozen.
15264 if Present (Interface_Alias (Subp)) then
15268 -- If the generic actual is present find the corresponding
15269 -- operation in the generic actual. If the parent type is a
15270 -- direct ancestor of the derived type then, even if it is an
15271 -- interface, the operations are inherited from the primary
15272 -- dispatch table and are in the proper order. If we detect here
15273 -- that primitives are not in the same order we traverse the list
15274 -- of primitive operations of the actual to find the one that
15275 -- implements the interface primitive.
15279 (Present (Generic_Actual)
15280 and then Present (Act_Subp)
15282 (Primitive_Names_Match (Subp, Act_Subp)
15284 Type_Conformant (Subp, Act_Subp,
15285 Skip_Controlling_Formals => True)))
15287 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual,
15288 Use_Full_View => True));
15290 -- Remember that we need searching for all pending primitives
15292 Need_Search := True;
15294 -- Handle entities associated with interface primitives
15296 if Present (Alias_Subp)
15297 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
15298 and then not Is_Predefined_Dispatching_Operation (Subp)
15300 -- Search for the primitive in the homonym chain
15303 Find_Primitive_Covering_Interface
15304 (Tagged_Type => Generic_Actual,
15305 Iface_Prim => Alias_Subp);
15307 -- Previous search may not locate primitives covering
15308 -- interfaces defined in generics units or instantiations.
15309 -- (it fails if the covering primitive has formals whose
15310 -- type is also defined in generics or instantiations).
15311 -- In such case we search in the list of primitives of the
15312 -- generic actual for the internal entity that links the
15313 -- interface primitive and the covering primitive.
15316 and then Is_Generic_Type (Parent_Type)
15318 -- This code has been designed to handle only generic
15319 -- formals that implement interfaces that are defined
15320 -- in a generic unit or instantiation. If this code is
15321 -- needed for other cases we must review it because
15322 -- (given that it relies on Original_Location to locate
15323 -- the primitive of Generic_Actual that covers the
15324 -- interface) it could leave linked through attribute
15325 -- Alias entities of unrelated instantiations).
15329 (Scope (Find_Dispatching_Type (Alias_Subp)))
15331 Instantiation_Depth
15332 (Sloc (Find_Dispatching_Type (Alias_Subp))) > 0);
15335 Iface_Prim_Loc : constant Source_Ptr :=
15336 Original_Location (Sloc (Alias_Subp));
15343 First_Elmt (Primitive_Operations (Generic_Actual));
15345 Search : while Present (Elmt) loop
15346 Prim := Node (Elmt);
15348 if Present (Interface_Alias (Prim))
15349 and then Original_Location
15350 (Sloc (Interface_Alias (Prim))) =
15353 Act_Subp := Alias (Prim);
15362 pragma Assert (Present (Act_Subp)
15363 or else Is_Abstract_Type (Generic_Actual)
15364 or else Serious_Errors_Detected > 0);
15366 -- Handle predefined primitives plus the rest of user-defined
15370 Act_Elmt := First_Elmt (Act_List);
15371 while Present (Act_Elmt) loop
15372 Act_Subp := Node (Act_Elmt);
15374 exit when Primitive_Names_Match (Subp, Act_Subp)
15375 and then Type_Conformant
15377 Skip_Controlling_Formals => True)
15378 and then No (Interface_Alias (Act_Subp));
15380 Next_Elmt (Act_Elmt);
15383 if No (Act_Elmt) then
15389 -- Case 1: If the parent is a limited interface then it has the
15390 -- predefined primitives of synchronized interfaces. However, the
15391 -- actual type may be a non-limited type and hence it does not
15392 -- have such primitives.
15394 if Present (Generic_Actual)
15395 and then not Present (Act_Subp)
15396 and then Is_Limited_Interface (Parent_Base)
15397 and then Is_Predefined_Interface_Primitive (Subp)
15401 -- Case 2: Inherit entities associated with interfaces that were
15402 -- not covered by the parent type. We exclude here null interface
15403 -- primitives because they do not need special management.
15405 -- We also exclude interface operations that are renamings. If the
15406 -- subprogram is an explicit renaming of an interface primitive,
15407 -- it is a regular primitive operation, and the presence of its
15408 -- alias is not relevant: it has to be derived like any other
15411 elsif Present (Alias (Subp))
15412 and then Nkind (Unit_Declaration_Node (Subp)) /=
15413 N_Subprogram_Renaming_Declaration
15414 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
15416 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
15417 and then Null_Present (Parent (Alias_Subp)))
15419 -- If this is an abstract private type then we transfer the
15420 -- derivation of the interface primitive from the partial view
15421 -- to the full view. This is safe because all the interfaces
15422 -- must be visible in the partial view. Done to avoid adding
15423 -- a new interface derivation to the private part of the
15424 -- enclosing package; otherwise this new derivation would be
15425 -- decorated as hidden when the analysis of the enclosing
15426 -- package completes.
15428 if Is_Abstract_Type (Derived_Type)
15429 and then In_Private_Part (Current_Scope)
15430 and then Has_Private_Declaration (Derived_Type)
15433 Partial_View : Entity_Id;
15438 Partial_View := First_Entity (Current_Scope);
15440 exit when No (Partial_View)
15441 or else (Has_Private_Declaration (Partial_View)
15443 Full_View (Partial_View) = Derived_Type);
15445 Next_Entity (Partial_View);
15448 -- If the partial view was not found then the source code
15449 -- has errors and the derivation is not needed.
15451 if Present (Partial_View) then
15453 First_Elmt (Primitive_Operations (Partial_View));
15454 while Present (Elmt) loop
15455 Ent := Node (Elmt);
15457 if Present (Alias (Ent))
15458 and then Ultimate_Alias (Ent) = Alias (Subp)
15461 (Ent, Primitive_Operations (Derived_Type));
15468 -- If the interface primitive was not found in the
15469 -- partial view then this interface primitive was
15470 -- overridden. We add a derivation to activate in
15471 -- Derive_Progenitor_Subprograms the machinery to
15475 Derive_Interface_Subprogram
15476 (New_Subp => New_Subp,
15478 Actual_Subp => Act_Subp);
15483 Derive_Interface_Subprogram
15484 (New_Subp => New_Subp,
15486 Actual_Subp => Act_Subp);
15489 -- Case 3: Common derivation
15493 (New_Subp => New_Subp,
15494 Parent_Subp => Subp,
15495 Derived_Type => Derived_Type,
15496 Parent_Type => Parent_Base,
15497 Actual_Subp => Act_Subp);
15500 -- No need to update Act_Elm if we must search for the
15501 -- corresponding operation in the generic actual
15504 and then Present (Act_Elmt)
15506 Next_Elmt (Act_Elmt);
15507 Act_Subp := Node (Act_Elmt);
15514 -- Inherit additional operations from progenitors. If the derived
15515 -- type is a generic actual, there are not new primitive operations
15516 -- for the type because it has those of the actual, and therefore
15517 -- nothing needs to be done. The renamings generated above are not
15518 -- primitive operations, and their purpose is simply to make the
15519 -- proper operations visible within an instantiation.
15521 if No (Generic_Actual) then
15522 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
15526 -- Final check: Direct descendants must have their primitives in the
15527 -- same order. We exclude from this test untagged types and instances
15528 -- of formal derived types. We skip this test if we have already
15529 -- reported serious errors in the sources.
15531 pragma Assert (not Is_Tagged_Type (Derived_Type)
15532 or else Present (Generic_Actual)
15533 or else Serious_Errors_Detected > 0
15534 or else Check_Derived_Type);
15535 end Derive_Subprograms;
15537 --------------------------------
15538 -- Derived_Standard_Character --
15539 --------------------------------
15541 procedure Derived_Standard_Character
15543 Parent_Type : Entity_Id;
15544 Derived_Type : Entity_Id)
15546 Loc : constant Source_Ptr := Sloc (N);
15547 Def : constant Node_Id := Type_Definition (N);
15548 Indic : constant Node_Id := Subtype_Indication (Def);
15549 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
15550 Implicit_Base : constant Entity_Id :=
15552 (E_Enumeration_Type, N, Derived_Type, 'B');
15558 Discard_Node (Process_Subtype (Indic, N));
15560 Set_Etype (Implicit_Base, Parent_Base);
15561 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
15562 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
15564 Set_Is_Character_Type (Implicit_Base, True);
15565 Set_Has_Delayed_Freeze (Implicit_Base);
15567 -- The bounds of the implicit base are the bounds of the parent base.
15568 -- Note that their type is the parent base.
15570 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
15571 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
15573 Set_Scalar_Range (Implicit_Base,
15576 High_Bound => Hi));
15578 Conditional_Delay (Derived_Type, Parent_Type);
15580 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
15581 Set_Etype (Derived_Type, Implicit_Base);
15582 Set_Size_Info (Derived_Type, Parent_Type);
15584 if Unknown_RM_Size (Derived_Type) then
15585 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
15588 Set_Is_Character_Type (Derived_Type, True);
15590 if Nkind (Indic) /= N_Subtype_Indication then
15592 -- If no explicit constraint, the bounds are those
15593 -- of the parent type.
15595 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
15596 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
15597 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
15600 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
15602 -- Because the implicit base is used in the conversion of the bounds, we
15603 -- have to freeze it now. This is similar to what is done for numeric
15604 -- types, and it equally suspicious, but otherwise a non-static bound
15605 -- will have a reference to an unfrozen type, which is rejected by Gigi
15606 -- (???). This requires specific care for definition of stream
15607 -- attributes. For details, see comments at the end of
15608 -- Build_Derived_Numeric_Type.
15610 Freeze_Before (N, Implicit_Base);
15611 end Derived_Standard_Character;
15613 ------------------------------
15614 -- Derived_Type_Declaration --
15615 ------------------------------
15617 procedure Derived_Type_Declaration
15620 Is_Completion : Boolean)
15622 Parent_Type : Entity_Id;
15624 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
15625 -- Check whether the parent type is a generic formal, or derives
15626 -- directly or indirectly from one.
15628 ------------------------
15629 -- Comes_From_Generic --
15630 ------------------------
15632 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
15634 if Is_Generic_Type (Typ) then
15637 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
15640 elsif Is_Private_Type (Typ)
15641 and then Present (Full_View (Typ))
15642 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
15646 elsif Is_Generic_Actual_Type (Typ) then
15652 end Comes_From_Generic;
15656 Def : constant Node_Id := Type_Definition (N);
15657 Iface_Def : Node_Id;
15658 Indic : constant Node_Id := Subtype_Indication (Def);
15659 Extension : constant Node_Id := Record_Extension_Part (Def);
15660 Parent_Node : Node_Id;
15663 -- Start of processing for Derived_Type_Declaration
15666 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
15668 -- Ada 2005 (AI-251): In case of interface derivation check that the
15669 -- parent is also an interface.
15671 if Interface_Present (Def) then
15672 Check_SPARK_05_Restriction ("interface is not allowed", Def);
15674 if not Is_Interface (Parent_Type) then
15675 Diagnose_Interface (Indic, Parent_Type);
15678 Parent_Node := Parent (Base_Type (Parent_Type));
15679 Iface_Def := Type_Definition (Parent_Node);
15681 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
15682 -- other limited interfaces.
15684 if Limited_Present (Def) then
15685 if Limited_Present (Iface_Def) then
15688 elsif Protected_Present (Iface_Def) then
15690 ("descendant of & must be declared as a protected "
15691 & "interface", N, Parent_Type);
15693 elsif Synchronized_Present (Iface_Def) then
15695 ("descendant of & must be declared as a synchronized "
15696 & "interface", N, Parent_Type);
15698 elsif Task_Present (Iface_Def) then
15700 ("descendant of & must be declared as a task interface",
15705 ("(Ada 2005) limited interface cannot inherit from "
15706 & "non-limited interface", Indic);
15709 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
15710 -- from non-limited or limited interfaces.
15712 elsif not Protected_Present (Def)
15713 and then not Synchronized_Present (Def)
15714 and then not Task_Present (Def)
15716 if Limited_Present (Iface_Def) then
15719 elsif Protected_Present (Iface_Def) then
15721 ("descendant of & must be declared as a protected "
15722 & "interface", N, Parent_Type);
15724 elsif Synchronized_Present (Iface_Def) then
15726 ("descendant of & must be declared as a synchronized "
15727 & "interface", N, Parent_Type);
15729 elsif Task_Present (Iface_Def) then
15731 ("descendant of & must be declared as a task interface",
15740 if Is_Tagged_Type (Parent_Type)
15741 and then Is_Concurrent_Type (Parent_Type)
15742 and then not Is_Interface (Parent_Type)
15745 ("parent type of a record extension cannot be a synchronized "
15746 & "tagged type (RM 3.9.1 (3/1))", N);
15747 Set_Etype (T, Any_Type);
15751 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
15754 if Is_Tagged_Type (Parent_Type)
15755 and then Is_Non_Empty_List (Interface_List (Def))
15762 Intf := First (Interface_List (Def));
15763 while Present (Intf) loop
15764 T := Find_Type_Of_Subtype_Indic (Intf);
15766 if not Is_Interface (T) then
15767 Diagnose_Interface (Intf, T);
15769 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
15770 -- a limited type from having a nonlimited progenitor.
15772 elsif (Limited_Present (Def)
15773 or else (not Is_Interface (Parent_Type)
15774 and then Is_Limited_Type (Parent_Type)))
15775 and then not Is_Limited_Interface (T)
15778 ("progenitor interface& of limited type must be limited",
15787 if Parent_Type = Any_Type
15788 or else Etype (Parent_Type) = Any_Type
15789 or else (Is_Class_Wide_Type (Parent_Type)
15790 and then Etype (Parent_Type) = T)
15792 -- If Parent_Type is undefined or illegal, make new type into a
15793 -- subtype of Any_Type, and set a few attributes to prevent cascaded
15794 -- errors. If this is a self-definition, emit error now.
15796 if T = Parent_Type or else T = Etype (Parent_Type) then
15797 Error_Msg_N ("type cannot be used in its own definition", Indic);
15800 Set_Ekind (T, Ekind (Parent_Type));
15801 Set_Etype (T, Any_Type);
15802 Set_Scalar_Range (T, Scalar_Range (Any_Type));
15804 if Is_Tagged_Type (T)
15805 and then Is_Record_Type (T)
15807 Set_Direct_Primitive_Operations (T, New_Elmt_List);
15813 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
15814 -- an interface is special because the list of interfaces in the full
15815 -- view can be given in any order. For example:
15817 -- type A is interface;
15818 -- type B is interface and A;
15819 -- type D is new B with private;
15821 -- type D is new A and B with null record; -- 1 --
15823 -- In this case we perform the following transformation of -1-:
15825 -- type D is new B and A with null record;
15827 -- If the parent of the full-view covers the parent of the partial-view
15828 -- we have two possible cases:
15830 -- 1) They have the same parent
15831 -- 2) The parent of the full-view implements some further interfaces
15833 -- In both cases we do not need to perform the transformation. In the
15834 -- first case the source program is correct and the transformation is
15835 -- not needed; in the second case the source program does not fulfill
15836 -- the no-hidden interfaces rule (AI-396) and the error will be reported
15839 -- This transformation not only simplifies the rest of the analysis of
15840 -- this type declaration but also simplifies the correct generation of
15841 -- the object layout to the expander.
15843 if In_Private_Part (Current_Scope)
15844 and then Is_Interface (Parent_Type)
15848 Partial_View : Entity_Id;
15849 Partial_View_Parent : Entity_Id;
15850 New_Iface : Node_Id;
15853 -- Look for the associated private type declaration
15855 Partial_View := First_Entity (Current_Scope);
15857 exit when No (Partial_View)
15858 or else (Has_Private_Declaration (Partial_View)
15859 and then Full_View (Partial_View) = T);
15861 Next_Entity (Partial_View);
15864 -- If the partial view was not found then the source code has
15865 -- errors and the transformation is not needed.
15867 if Present (Partial_View) then
15868 Partial_View_Parent := Etype (Partial_View);
15870 -- If the parent of the full-view covers the parent of the
15871 -- partial-view we have nothing else to do.
15873 if Interface_Present_In_Ancestor
15874 (Parent_Type, Partial_View_Parent)
15878 -- Traverse the list of interfaces of the full-view to look
15879 -- for the parent of the partial-view and perform the tree
15883 Iface := First (Interface_List (Def));
15884 while Present (Iface) loop
15885 if Etype (Iface) = Etype (Partial_View) then
15886 Rewrite (Subtype_Indication (Def),
15887 New_Copy (Subtype_Indication
15888 (Parent (Partial_View))));
15891 Make_Identifier (Sloc (N), Chars (Parent_Type));
15892 Append (New_Iface, Interface_List (Def));
15894 -- Analyze the transformed code
15896 Derived_Type_Declaration (T, N, Is_Completion);
15907 -- Only composite types other than array types are allowed to have
15910 if Present (Discriminant_Specifications (N)) then
15911 if (Is_Elementary_Type (Parent_Type)
15913 Is_Array_Type (Parent_Type))
15914 and then not Error_Posted (N)
15917 ("elementary or array type cannot have discriminants",
15918 Defining_Identifier (First (Discriminant_Specifications (N))));
15919 Set_Has_Discriminants (T, False);
15921 -- The type is allowed to have discriminants
15924 Check_SPARK_05_Restriction ("discriminant type is not allowed", N);
15928 -- In Ada 83, a derived type defined in a package specification cannot
15929 -- be used for further derivation until the end of its visible part.
15930 -- Note that derivation in the private part of the package is allowed.
15932 if Ada_Version = Ada_83
15933 and then Is_Derived_Type (Parent_Type)
15934 and then In_Visible_Part (Scope (Parent_Type))
15936 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
15938 ("(Ada 83): premature use of type for derivation", Indic);
15942 -- Check for early use of incomplete or private type
15944 if Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
15945 Error_Msg_N ("premature derivation of incomplete type", Indic);
15948 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
15949 and then not Comes_From_Generic (Parent_Type))
15950 or else Has_Private_Component (Parent_Type)
15952 -- The ancestor type of a formal type can be incomplete, in which
15953 -- case only the operations of the partial view are available in the
15954 -- generic. Subsequent checks may be required when the full view is
15955 -- analyzed to verify that a derivation from a tagged type has an
15958 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
15961 elsif No (Underlying_Type (Parent_Type))
15962 or else Has_Private_Component (Parent_Type)
15965 ("premature derivation of derived or private type", Indic);
15967 -- Flag the type itself as being in error, this prevents some
15968 -- nasty problems with subsequent uses of the malformed type.
15970 Set_Error_Posted (T);
15972 -- Check that within the immediate scope of an untagged partial
15973 -- view it's illegal to derive from the partial view if the
15974 -- full view is tagged. (7.3(7))
15976 -- We verify that the Parent_Type is a partial view by checking
15977 -- that it is not a Full_Type_Declaration (i.e. a private type or
15978 -- private extension declaration), to distinguish a partial view
15979 -- from a derivation from a private type which also appears as
15980 -- E_Private_Type. If the parent base type is not declared in an
15981 -- enclosing scope there is no need to check.
15983 elsif Present (Full_View (Parent_Type))
15984 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
15985 and then not Is_Tagged_Type (Parent_Type)
15986 and then Is_Tagged_Type (Full_View (Parent_Type))
15987 and then In_Open_Scopes (Scope (Base_Type (Parent_Type)))
15990 ("premature derivation from type with tagged full view",
15995 -- Check that form of derivation is appropriate
15997 Taggd := Is_Tagged_Type (Parent_Type);
15999 -- Set the parent type to the class-wide type's specific type in this
16000 -- case to prevent cascading errors
16002 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
16003 Error_Msg_N ("parent type must not be a class-wide type", Indic);
16004 Set_Etype (T, Etype (Parent_Type));
16008 if Present (Extension) and then not Taggd then
16010 ("type derived from untagged type cannot have extension", Indic);
16012 elsif No (Extension) and then Taggd then
16014 -- If this declaration is within a private part (or body) of a
16015 -- generic instantiation then the derivation is allowed (the parent
16016 -- type can only appear tagged in this case if it's a generic actual
16017 -- type, since it would otherwise have been rejected in the analysis
16018 -- of the generic template).
16020 if not Is_Generic_Actual_Type (Parent_Type)
16021 or else In_Visible_Part (Scope (Parent_Type))
16023 if Is_Class_Wide_Type (Parent_Type) then
16025 ("parent type must not be a class-wide type", Indic);
16027 -- Use specific type to prevent cascaded errors.
16029 Parent_Type := Etype (Parent_Type);
16033 ("type derived from tagged type must have extension", Indic);
16038 -- AI-443: Synchronized formal derived types require a private
16039 -- extension. There is no point in checking the ancestor type or
16040 -- the progenitors since the construct is wrong to begin with.
16042 if Ada_Version >= Ada_2005
16043 and then Is_Generic_Type (T)
16044 and then Present (Original_Node (N))
16047 Decl : constant Node_Id := Original_Node (N);
16050 if Nkind (Decl) = N_Formal_Type_Declaration
16051 and then Nkind (Formal_Type_Definition (Decl)) =
16052 N_Formal_Derived_Type_Definition
16053 and then Synchronized_Present (Formal_Type_Definition (Decl))
16054 and then No (Extension)
16056 -- Avoid emitting a duplicate error message
16058 and then not Error_Posted (Indic)
16061 ("synchronized derived type must have extension", N);
16066 if Null_Exclusion_Present (Def)
16067 and then not Is_Access_Type (Parent_Type)
16069 Error_Msg_N ("null exclusion can only apply to an access type", N);
16072 -- Avoid deriving parent primitives of underlying record views
16074 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
16075 Derive_Subps => not Is_Underlying_Record_View (T));
16077 -- AI-419: The parent type of an explicitly limited derived type must
16078 -- be a limited type or a limited interface.
16080 if Limited_Present (Def) then
16081 Set_Is_Limited_Record (T);
16083 if Is_Interface (T) then
16084 Set_Is_Limited_Interface (T);
16087 if not Is_Limited_Type (Parent_Type)
16089 (not Is_Interface (Parent_Type)
16090 or else not Is_Limited_Interface (Parent_Type))
16092 -- AI05-0096: a derivation in the private part of an instance is
16093 -- legal if the generic formal is untagged limited, and the actual
16096 if Is_Generic_Actual_Type (Parent_Type)
16097 and then In_Private_Part (Current_Scope)
16100 (Generic_Parent_Type (Parent (Parent_Type)))
16106 ("parent type& of limited type must be limited",
16112 -- In SPARK, there are no derived type definitions other than type
16113 -- extensions of tagged record types.
16115 if No (Extension) then
16116 Check_SPARK_05_Restriction
16117 ("derived type is not allowed", Original_Node (N));
16119 end Derived_Type_Declaration;
16121 ------------------------
16122 -- Diagnose_Interface --
16123 ------------------------
16125 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
16127 if not Is_Interface (E) and then E /= Any_Type then
16128 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
16130 end Diagnose_Interface;
16132 ----------------------------------
16133 -- Enumeration_Type_Declaration --
16134 ----------------------------------
16136 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
16143 -- Create identifier node representing lower bound
16145 B_Node := New_Node (N_Identifier, Sloc (Def));
16146 L := First (Literals (Def));
16147 Set_Chars (B_Node, Chars (L));
16148 Set_Entity (B_Node, L);
16149 Set_Etype (B_Node, T);
16150 Set_Is_Static_Expression (B_Node, True);
16152 R_Node := New_Node (N_Range, Sloc (Def));
16153 Set_Low_Bound (R_Node, B_Node);
16155 Set_Ekind (T, E_Enumeration_Type);
16156 Set_First_Literal (T, L);
16158 Set_Is_Constrained (T);
16162 -- Loop through literals of enumeration type setting pos and rep values
16163 -- except that if the Ekind is already set, then it means the literal
16164 -- was already constructed (case of a derived type declaration and we
16165 -- should not disturb the Pos and Rep values.
16167 while Present (L) loop
16168 if Ekind (L) /= E_Enumeration_Literal then
16169 Set_Ekind (L, E_Enumeration_Literal);
16170 Set_Enumeration_Pos (L, Ev);
16171 Set_Enumeration_Rep (L, Ev);
16172 Set_Is_Known_Valid (L, True);
16176 New_Overloaded_Entity (L);
16177 Generate_Definition (L);
16178 Set_Convention (L, Convention_Intrinsic);
16180 -- Case of character literal
16182 if Nkind (L) = N_Defining_Character_Literal then
16183 Set_Is_Character_Type (T, True);
16185 -- Check violation of No_Wide_Characters
16187 if Restriction_Check_Required (No_Wide_Characters) then
16188 Get_Name_String (Chars (L));
16190 if Name_Len >= 3 and then Name_Buffer (1 .. 2) = "QW" then
16191 Check_Restriction (No_Wide_Characters, L);
16200 -- Now create a node representing upper bound
16202 B_Node := New_Node (N_Identifier, Sloc (Def));
16203 Set_Chars (B_Node, Chars (Last (Literals (Def))));
16204 Set_Entity (B_Node, Last (Literals (Def)));
16205 Set_Etype (B_Node, T);
16206 Set_Is_Static_Expression (B_Node, True);
16208 Set_High_Bound (R_Node, B_Node);
16210 -- Initialize various fields of the type. Some of this information
16211 -- may be overwritten later through rep.clauses.
16213 Set_Scalar_Range (T, R_Node);
16214 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
16215 Set_Enum_Esize (T);
16216 Set_Enum_Pos_To_Rep (T, Empty);
16218 -- Set Discard_Names if configuration pragma set, or if there is
16219 -- a parameterless pragma in the current declarative region
16221 if Global_Discard_Names or else Discard_Names (Scope (T)) then
16222 Set_Discard_Names (T);
16225 -- Process end label if there is one
16227 if Present (Def) then
16228 Process_End_Label (Def, 'e', T);
16230 end Enumeration_Type_Declaration;
16232 ---------------------------------
16233 -- Expand_To_Stored_Constraint --
16234 ---------------------------------
16236 function Expand_To_Stored_Constraint
16238 Constraint : Elist_Id) return Elist_Id
16240 Explicitly_Discriminated_Type : Entity_Id;
16241 Expansion : Elist_Id;
16242 Discriminant : Entity_Id;
16244 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
16245 -- Find the nearest type that actually specifies discriminants
16247 ---------------------------------
16248 -- Type_With_Explicit_Discrims --
16249 ---------------------------------
16251 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
16252 Typ : constant E := Base_Type (Id);
16255 if Ekind (Typ) in Incomplete_Or_Private_Kind then
16256 if Present (Full_View (Typ)) then
16257 return Type_With_Explicit_Discrims (Full_View (Typ));
16261 if Has_Discriminants (Typ) then
16266 if Etype (Typ) = Typ then
16268 elsif Has_Discriminants (Typ) then
16271 return Type_With_Explicit_Discrims (Etype (Typ));
16274 end Type_With_Explicit_Discrims;
16276 -- Start of processing for Expand_To_Stored_Constraint
16279 if No (Constraint) or else Is_Empty_Elmt_List (Constraint) then
16283 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
16285 if No (Explicitly_Discriminated_Type) then
16289 Expansion := New_Elmt_List;
16292 First_Stored_Discriminant (Explicitly_Discriminated_Type);
16293 while Present (Discriminant) loop
16295 (Get_Discriminant_Value
16296 (Discriminant, Explicitly_Discriminated_Type, Constraint),
16298 Next_Stored_Discriminant (Discriminant);
16302 end Expand_To_Stored_Constraint;
16304 ---------------------------
16305 -- Find_Hidden_Interface --
16306 ---------------------------
16308 function Find_Hidden_Interface
16310 Dest : Elist_Id) return Entity_Id
16313 Iface_Elmt : Elmt_Id;
16316 if Present (Src) and then Present (Dest) then
16317 Iface_Elmt := First_Elmt (Src);
16318 while Present (Iface_Elmt) loop
16319 Iface := Node (Iface_Elmt);
16321 if Is_Interface (Iface)
16322 and then not Contain_Interface (Iface, Dest)
16327 Next_Elmt (Iface_Elmt);
16332 end Find_Hidden_Interface;
16334 --------------------
16335 -- Find_Type_Name --
16336 --------------------
16338 function Find_Type_Name (N : Node_Id) return Entity_Id is
16339 Id : constant Entity_Id := Defining_Identifier (N);
16341 New_Id : Entity_Id;
16342 Prev_Par : Node_Id;
16344 procedure Check_Duplicate_Aspects;
16345 -- Check that aspects specified in a completion have not been specified
16346 -- already in the partial view. Type_Invariant and others can be
16347 -- specified on either view but never on both.
16349 procedure Tag_Mismatch;
16350 -- Diagnose a tagged partial view whose full view is untagged.
16351 -- We post the message on the full view, with a reference to
16352 -- the previous partial view. The partial view can be private
16353 -- or incomplete, and these are handled in a different manner,
16354 -- so we determine the position of the error message from the
16355 -- respective slocs of both.
16357 -----------------------------
16358 -- Check_Duplicate_Aspects --
16359 -----------------------------
16361 procedure Check_Duplicate_Aspects is
16362 Prev_Aspects : constant List_Id := Aspect_Specifications (Prev_Par);
16363 Full_Aspects : constant List_Id := Aspect_Specifications (N);
16364 F_Spec, P_Spec : Node_Id;
16367 if Present (Full_Aspects) then
16368 F_Spec := First (Full_Aspects);
16369 while Present (F_Spec) loop
16370 if Present (Prev_Aspects) then
16371 P_Spec := First (Prev_Aspects);
16372 while Present (P_Spec) loop
16373 if Chars (Identifier (P_Spec)) =
16374 Chars (Identifier (F_Spec))
16377 ("aspect already specified in private declaration",
16387 if Has_Discriminants (Prev)
16388 and then not Has_Unknown_Discriminants (Prev)
16389 and then Chars (Identifier (F_Spec)) =
16390 Name_Implicit_Dereference
16392 Error_Msg_N ("cannot specify aspect " &
16393 "if partial view has known discriminants", F_Spec);
16399 end Check_Duplicate_Aspects;
16405 procedure Tag_Mismatch is
16407 if Sloc (Prev) < Sloc (Id) then
16408 if Ada_Version >= Ada_2012
16409 and then Nkind (N) = N_Private_Type_Declaration
16412 ("declaration of private } must be a tagged type ", Id, Prev);
16415 ("full declaration of } must be a tagged type ", Id, Prev);
16419 if Ada_Version >= Ada_2012
16420 and then Nkind (N) = N_Private_Type_Declaration
16423 ("declaration of private } must be a tagged type ", Prev, Id);
16426 ("full declaration of } must be a tagged type ", Prev, Id);
16431 -- Start of processing for Find_Type_Name
16434 -- Find incomplete declaration, if one was given
16436 Prev := Current_Entity_In_Scope (Id);
16438 -- New type declaration
16444 -- Previous declaration exists
16447 Prev_Par := Parent (Prev);
16449 -- Error if not incomplete/private case except if previous
16450 -- declaration is implicit, etc. Enter_Name will emit error if
16453 if not Is_Incomplete_Or_Private_Type (Prev) then
16457 -- Check invalid completion of private or incomplete type
16459 elsif not Nkind_In (N, N_Full_Type_Declaration,
16460 N_Task_Type_Declaration,
16461 N_Protected_Type_Declaration)
16463 (Ada_Version < Ada_2012
16464 or else not Is_Incomplete_Type (Prev)
16465 or else not Nkind_In (N, N_Private_Type_Declaration,
16466 N_Private_Extension_Declaration))
16468 -- Completion must be a full type declarations (RM 7.3(4))
16470 Error_Msg_Sloc := Sloc (Prev);
16471 Error_Msg_NE ("invalid completion of }", Id, Prev);
16473 -- Set scope of Id to avoid cascaded errors. Entity is never
16474 -- examined again, except when saving globals in generics.
16476 Set_Scope (Id, Current_Scope);
16479 -- If this is a repeated incomplete declaration, no further
16480 -- checks are possible.
16482 if Nkind (N) = N_Incomplete_Type_Declaration then
16486 -- Case of full declaration of incomplete type
16488 elsif Ekind (Prev) = E_Incomplete_Type
16489 and then (Ada_Version < Ada_2012
16490 or else No (Full_View (Prev))
16491 or else not Is_Private_Type (Full_View (Prev)))
16493 -- Indicate that the incomplete declaration has a matching full
16494 -- declaration. The defining occurrence of the incomplete
16495 -- declaration remains the visible one, and the procedure
16496 -- Get_Full_View dereferences it whenever the type is used.
16498 if Present (Full_View (Prev)) then
16499 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
16502 Set_Full_View (Prev, Id);
16503 Append_Entity (Id, Current_Scope);
16504 Set_Is_Public (Id, Is_Public (Prev));
16505 Set_Is_Internal (Id);
16508 -- If the incomplete view is tagged, a class_wide type has been
16509 -- created already. Use it for the private type as well, in order
16510 -- to prevent multiple incompatible class-wide types that may be
16511 -- created for self-referential anonymous access components.
16513 if Is_Tagged_Type (Prev)
16514 and then Present (Class_Wide_Type (Prev))
16516 Set_Ekind (Id, Ekind (Prev)); -- will be reset later
16517 Set_Class_Wide_Type (Id, Class_Wide_Type (Prev));
16519 -- The type of the classwide type is the current Id. Previously
16520 -- this was not done for private declarations because of order-
16521 -- of elaboration issues in the back-end, but gigi now handles
16524 Set_Etype (Class_Wide_Type (Id), Id);
16527 -- Case of full declaration of private type
16530 -- If the private type was a completion of an incomplete type then
16531 -- update Prev to reference the private type
16533 if Ada_Version >= Ada_2012
16534 and then Ekind (Prev) = E_Incomplete_Type
16535 and then Present (Full_View (Prev))
16536 and then Is_Private_Type (Full_View (Prev))
16538 Prev := Full_View (Prev);
16539 Prev_Par := Parent (Prev);
16542 if Nkind (N) = N_Full_Type_Declaration
16544 (Type_Definition (N), N_Record_Definition,
16545 N_Derived_Type_Definition)
16546 and then Interface_Present (Type_Definition (N))
16549 ("completion of private type cannot be an interface", N);
16552 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
16553 if Etype (Prev) /= Prev then
16555 -- Prev is a private subtype or a derived type, and needs
16558 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
16561 elsif Ekind (Prev) = E_Private_Type
16562 and then Nkind_In (N, N_Task_Type_Declaration,
16563 N_Protected_Type_Declaration)
16566 ("completion of nonlimited type cannot be limited", N);
16568 elsif Ekind (Prev) = E_Record_Type_With_Private
16569 and then Nkind_In (N, N_Task_Type_Declaration,
16570 N_Protected_Type_Declaration)
16572 if not Is_Limited_Record (Prev) then
16574 ("completion of nonlimited type cannot be limited", N);
16576 elsif No (Interface_List (N)) then
16578 ("completion of tagged private type must be tagged",
16583 -- Ada 2005 (AI-251): Private extension declaration of a task
16584 -- type or a protected type. This case arises when covering
16585 -- interface types.
16587 elsif Nkind_In (N, N_Task_Type_Declaration,
16588 N_Protected_Type_Declaration)
16592 elsif Nkind (N) /= N_Full_Type_Declaration
16593 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
16596 ("full view of private extension must be an extension", N);
16598 elsif not (Abstract_Present (Parent (Prev)))
16599 and then Abstract_Present (Type_Definition (N))
16602 ("full view of non-abstract extension cannot be abstract", N);
16605 if not In_Private_Part (Current_Scope) then
16607 ("declaration of full view must appear in private part", N);
16610 if Ada_Version >= Ada_2012 then
16611 Check_Duplicate_Aspects;
16614 Copy_And_Swap (Prev, Id);
16615 Set_Has_Private_Declaration (Prev);
16616 Set_Has_Private_Declaration (Id);
16618 -- AI12-0133: Indicate whether we have a partial view with
16619 -- unknown discriminants, in which case initialization of objects
16620 -- of the type do not receive an invariant check.
16622 Set_Partial_View_Has_Unknown_Discr
16623 (Prev, Has_Unknown_Discriminants (Id));
16625 -- Preserve aspect and iterator flags that may have been set on
16626 -- the partial view.
16628 Set_Has_Delayed_Aspects (Prev, Has_Delayed_Aspects (Id));
16629 Set_Has_Implicit_Dereference (Prev, Has_Implicit_Dereference (Id));
16631 -- If no error, propagate freeze_node from private to full view.
16632 -- It may have been generated for an early operational item.
16634 if Present (Freeze_Node (Id))
16635 and then Serious_Errors_Detected = 0
16636 and then No (Full_View (Id))
16638 Set_Freeze_Node (Prev, Freeze_Node (Id));
16639 Set_Freeze_Node (Id, Empty);
16640 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
16643 Set_Full_View (Id, Prev);
16647 -- Verify that full declaration conforms to partial one
16649 if Is_Incomplete_Or_Private_Type (Prev)
16650 and then Present (Discriminant_Specifications (Prev_Par))
16652 if Present (Discriminant_Specifications (N)) then
16653 if Ekind (Prev) = E_Incomplete_Type then
16654 Check_Discriminant_Conformance (N, Prev, Prev);
16656 Check_Discriminant_Conformance (N, Prev, Id);
16661 ("missing discriminants in full type declaration", N);
16663 -- To avoid cascaded errors on subsequent use, share the
16664 -- discriminants of the partial view.
16666 Set_Discriminant_Specifications (N,
16667 Discriminant_Specifications (Prev_Par));
16671 -- A prior untagged partial view can have an associated class-wide
16672 -- type due to use of the class attribute, and in this case the full
16673 -- type must also be tagged. This Ada 95 usage is deprecated in favor
16674 -- of incomplete tagged declarations, but we check for it.
16677 and then (Is_Tagged_Type (Prev)
16678 or else Present (Class_Wide_Type (Prev)))
16680 -- Ada 2012 (AI05-0162): A private type may be the completion of
16681 -- an incomplete type.
16683 if Ada_Version >= Ada_2012
16684 and then Is_Incomplete_Type (Prev)
16685 and then Nkind_In (N, N_Private_Type_Declaration,
16686 N_Private_Extension_Declaration)
16688 -- No need to check private extensions since they are tagged
16690 if Nkind (N) = N_Private_Type_Declaration
16691 and then not Tagged_Present (N)
16696 -- The full declaration is either a tagged type (including
16697 -- a synchronized type that implements interfaces) or a
16698 -- type extension, otherwise this is an error.
16700 elsif Nkind_In (N, N_Task_Type_Declaration,
16701 N_Protected_Type_Declaration)
16703 if No (Interface_List (N)) and then not Error_Posted (N) then
16707 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
16709 -- Indicate that the previous declaration (tagged incomplete
16710 -- or private declaration) requires the same on the full one.
16712 if not Tagged_Present (Type_Definition (N)) then
16714 Set_Is_Tagged_Type (Id);
16717 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
16718 if No (Record_Extension_Part (Type_Definition (N))) then
16720 ("full declaration of } must be a record extension",
16723 -- Set some attributes to produce a usable full view
16725 Set_Is_Tagged_Type (Id);
16734 and then Nkind (Parent (Prev)) = N_Incomplete_Type_Declaration
16735 and then Present (Premature_Use (Parent (Prev)))
16737 Error_Msg_Sloc := Sloc (N);
16739 ("\full declaration #", Premature_Use (Parent (Prev)));
16744 end Find_Type_Name;
16746 -------------------------
16747 -- Find_Type_Of_Object --
16748 -------------------------
16750 function Find_Type_Of_Object
16751 (Obj_Def : Node_Id;
16752 Related_Nod : Node_Id) return Entity_Id
16754 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
16755 P : Node_Id := Parent (Obj_Def);
16760 -- If the parent is a component_definition node we climb to the
16761 -- component_declaration node
16763 if Nkind (P) = N_Component_Definition then
16767 -- Case of an anonymous array subtype
16769 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
16770 N_Unconstrained_Array_Definition)
16773 Array_Type_Declaration (T, Obj_Def);
16775 -- Create an explicit subtype whenever possible
16777 elsif Nkind (P) /= N_Component_Declaration
16778 and then Def_Kind = N_Subtype_Indication
16780 -- Base name of subtype on object name, which will be unique in
16781 -- the current scope.
16783 -- If this is a duplicate declaration, return base type, to avoid
16784 -- generating duplicate anonymous types.
16786 if Error_Posted (P) then
16787 Analyze (Subtype_Mark (Obj_Def));
16788 return Entity (Subtype_Mark (Obj_Def));
16793 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
16795 T := Make_Defining_Identifier (Sloc (P), Nam);
16797 Insert_Action (Obj_Def,
16798 Make_Subtype_Declaration (Sloc (P),
16799 Defining_Identifier => T,
16800 Subtype_Indication => Relocate_Node (Obj_Def)));
16802 -- This subtype may need freezing, and this will not be done
16803 -- automatically if the object declaration is not in declarative
16804 -- part. Since this is an object declaration, the type cannot always
16805 -- be frozen here. Deferred constants do not freeze their type
16806 -- (which often enough will be private).
16808 if Nkind (P) = N_Object_Declaration
16809 and then Constant_Present (P)
16810 and then No (Expression (P))
16814 -- Here we freeze the base type of object type to catch premature use
16815 -- of discriminated private type without a full view.
16818 Insert_Actions (Obj_Def, Freeze_Entity (Base_Type (T), P));
16821 -- Ada 2005 AI-406: the object definition in an object declaration
16822 -- can be an access definition.
16824 elsif Def_Kind = N_Access_Definition then
16825 T := Access_Definition (Related_Nod, Obj_Def);
16827 Set_Is_Local_Anonymous_Access
16829 V => (Ada_Version < Ada_2012)
16830 or else (Nkind (P) /= N_Object_Declaration)
16831 or else Is_Library_Level_Entity (Defining_Identifier (P)));
16833 -- Otherwise, the object definition is just a subtype_mark
16836 T := Process_Subtype (Obj_Def, Related_Nod);
16838 -- If expansion is disabled an object definition that is an aggregate
16839 -- will not get expanded and may lead to scoping problems in the back
16840 -- end, if the object is referenced in an inner scope. In that case
16841 -- create an itype reference for the object definition now. This
16842 -- may be redundant in some cases, but harmless.
16845 and then Nkind (Related_Nod) = N_Object_Declaration
16848 Build_Itype_Reference (T, Related_Nod);
16853 end Find_Type_Of_Object;
16855 --------------------------------
16856 -- Find_Type_Of_Subtype_Indic --
16857 --------------------------------
16859 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
16863 -- Case of subtype mark with a constraint
16865 if Nkind (S) = N_Subtype_Indication then
16866 Find_Type (Subtype_Mark (S));
16867 Typ := Entity (Subtype_Mark (S));
16870 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
16873 ("incorrect constraint for this kind of type", Constraint (S));
16874 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
16877 -- Otherwise we have a subtype mark without a constraint
16879 elsif Error_Posted (S) then
16880 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
16888 -- Check No_Wide_Characters restriction
16890 Check_Wide_Character_Restriction (Typ, S);
16893 end Find_Type_Of_Subtype_Indic;
16895 -------------------------------------
16896 -- Floating_Point_Type_Declaration --
16897 -------------------------------------
16899 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
16900 Digs : constant Node_Id := Digits_Expression (Def);
16901 Max_Digs_Val : constant Uint := Digits_Value (Standard_Long_Long_Float);
16903 Base_Typ : Entity_Id;
16904 Implicit_Base : Entity_Id;
16907 function Can_Derive_From (E : Entity_Id) return Boolean;
16908 -- Find if given digits value, and possibly a specified range, allows
16909 -- derivation from specified type
16911 function Find_Base_Type return Entity_Id;
16912 -- Find a predefined base type that Def can derive from, or generate
16913 -- an error and substitute Long_Long_Float if none exists.
16915 ---------------------
16916 -- Can_Derive_From --
16917 ---------------------
16919 function Can_Derive_From (E : Entity_Id) return Boolean is
16920 Spec : constant Entity_Id := Real_Range_Specification (Def);
16923 -- Check specified "digits" constraint
16925 if Digs_Val > Digits_Value (E) then
16929 -- Check for matching range, if specified
16931 if Present (Spec) then
16932 if Expr_Value_R (Type_Low_Bound (E)) >
16933 Expr_Value_R (Low_Bound (Spec))
16938 if Expr_Value_R (Type_High_Bound (E)) <
16939 Expr_Value_R (High_Bound (Spec))
16946 end Can_Derive_From;
16948 --------------------
16949 -- Find_Base_Type --
16950 --------------------
16952 function Find_Base_Type return Entity_Id is
16953 Choice : Elmt_Id := First_Elmt (Predefined_Float_Types);
16956 -- Iterate over the predefined types in order, returning the first
16957 -- one that Def can derive from.
16959 while Present (Choice) loop
16960 if Can_Derive_From (Node (Choice)) then
16961 return Node (Choice);
16964 Next_Elmt (Choice);
16967 -- If we can't derive from any existing type, use Long_Long_Float
16968 -- and give appropriate message explaining the problem.
16970 if Digs_Val > Max_Digs_Val then
16971 -- It might be the case that there is a type with the requested
16972 -- range, just not the combination of digits and range.
16975 ("no predefined type has requested range and precision",
16976 Real_Range_Specification (Def));
16980 ("range too large for any predefined type",
16981 Real_Range_Specification (Def));
16984 return Standard_Long_Long_Float;
16985 end Find_Base_Type;
16987 -- Start of processing for Floating_Point_Type_Declaration
16990 Check_Restriction (No_Floating_Point, Def);
16992 -- Create an implicit base type
16995 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
16997 -- Analyze and verify digits value
16999 Analyze_And_Resolve (Digs, Any_Integer);
17000 Check_Digits_Expression (Digs);
17001 Digs_Val := Expr_Value (Digs);
17003 -- Process possible range spec and find correct type to derive from
17005 Process_Real_Range_Specification (Def);
17007 -- Check that requested number of digits is not too high.
17009 if Digs_Val > Max_Digs_Val then
17011 -- The check for Max_Base_Digits may be somewhat expensive, as it
17012 -- requires reading System, so only do it when necessary.
17015 Max_Base_Digits : constant Uint :=
17018 (Parent (RTE (RE_Max_Base_Digits))));
17021 if Digs_Val > Max_Base_Digits then
17022 Error_Msg_Uint_1 := Max_Base_Digits;
17023 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
17025 elsif No (Real_Range_Specification (Def)) then
17026 Error_Msg_Uint_1 := Max_Digs_Val;
17027 Error_Msg_N ("types with more than ^ digits need range spec "
17028 & "(RM 3.5.7(6))", Digs);
17033 -- Find a suitable type to derive from or complain and use a substitute
17035 Base_Typ := Find_Base_Type;
17037 -- If there are bounds given in the declaration use them as the bounds
17038 -- of the type, otherwise use the bounds of the predefined base type
17039 -- that was chosen based on the Digits value.
17041 if Present (Real_Range_Specification (Def)) then
17042 Set_Scalar_Range (T, Real_Range_Specification (Def));
17043 Set_Is_Constrained (T);
17045 -- The bounds of this range must be converted to machine numbers
17046 -- in accordance with RM 4.9(38).
17048 Bound := Type_Low_Bound (T);
17050 if Nkind (Bound) = N_Real_Literal then
17052 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
17053 Set_Is_Machine_Number (Bound);
17056 Bound := Type_High_Bound (T);
17058 if Nkind (Bound) = N_Real_Literal then
17060 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
17061 Set_Is_Machine_Number (Bound);
17065 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
17068 -- Complete definition of implicit base and declared first subtype. The
17069 -- inheritance of the rep item chain ensures that SPARK-related pragmas
17070 -- are not clobbered when the floating point type acts as a full view of
17073 Set_Etype (Implicit_Base, Base_Typ);
17074 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
17075 Set_Size_Info (Implicit_Base, Base_Typ);
17076 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
17077 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
17078 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
17079 Set_Float_Rep (Implicit_Base, Float_Rep (Base_Typ));
17081 Set_Ekind (T, E_Floating_Point_Subtype);
17082 Set_Etype (T, Implicit_Base);
17083 Set_Size_Info (T, Implicit_Base);
17084 Set_RM_Size (T, RM_Size (Implicit_Base));
17085 Inherit_Rep_Item_Chain (T, Implicit_Base);
17086 Set_Digits_Value (T, Digs_Val);
17087 end Floating_Point_Type_Declaration;
17089 ----------------------------
17090 -- Get_Discriminant_Value --
17091 ----------------------------
17093 -- This is the situation:
17095 -- There is a non-derived type
17097 -- type T0 (Dx, Dy, Dz...)
17099 -- There are zero or more levels of derivation, with each derivation
17100 -- either purely inheriting the discriminants, or defining its own.
17102 -- type Ti is new Ti-1
17104 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
17106 -- subtype Ti is ...
17108 -- The subtype issue is avoided by the use of Original_Record_Component,
17109 -- and the fact that derived subtypes also derive the constraints.
17111 -- This chain leads back from
17113 -- Typ_For_Constraint
17115 -- Typ_For_Constraint has discriminants, and the value for each
17116 -- discriminant is given by its corresponding Elmt of Constraints.
17118 -- Discriminant is some discriminant in this hierarchy
17120 -- We need to return its value
17122 -- We do this by recursively searching each level, and looking for
17123 -- Discriminant. Once we get to the bottom, we start backing up
17124 -- returning the value for it which may in turn be a discriminant
17125 -- further up, so on the backup we continue the substitution.
17127 function Get_Discriminant_Value
17128 (Discriminant : Entity_Id;
17129 Typ_For_Constraint : Entity_Id;
17130 Constraint : Elist_Id) return Node_Id
17132 function Root_Corresponding_Discriminant
17133 (Discr : Entity_Id) return Entity_Id;
17134 -- Given a discriminant, traverse the chain of inherited discriminants
17135 -- and return the topmost discriminant.
17137 function Search_Derivation_Levels
17139 Discrim_Values : Elist_Id;
17140 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
17141 -- This is the routine that performs the recursive search of levels
17142 -- as described above.
17144 -------------------------------------
17145 -- Root_Corresponding_Discriminant --
17146 -------------------------------------
17148 function Root_Corresponding_Discriminant
17149 (Discr : Entity_Id) return Entity_Id
17155 while Present (Corresponding_Discriminant (D)) loop
17156 D := Corresponding_Discriminant (D);
17160 end Root_Corresponding_Discriminant;
17162 ------------------------------
17163 -- Search_Derivation_Levels --
17164 ------------------------------
17166 function Search_Derivation_Levels
17168 Discrim_Values : Elist_Id;
17169 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
17173 Result : Node_Or_Entity_Id;
17174 Result_Entity : Node_Id;
17177 -- If inappropriate type, return Error, this happens only in
17178 -- cascaded error situations, and we want to avoid a blow up.
17180 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
17184 -- Look deeper if possible. Use Stored_Constraints only for
17185 -- untagged types. For tagged types use the given constraint.
17186 -- This asymmetry needs explanation???
17188 if not Stored_Discrim_Values
17189 and then Present (Stored_Constraint (Ti))
17190 and then not Is_Tagged_Type (Ti)
17193 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
17196 Td : constant Entity_Id := Etype (Ti);
17200 Result := Discriminant;
17203 if Present (Stored_Constraint (Ti)) then
17205 Search_Derivation_Levels
17206 (Td, Stored_Constraint (Ti), True);
17209 Search_Derivation_Levels
17210 (Td, Discrim_Values, Stored_Discrim_Values);
17216 -- Extra underlying places to search, if not found above. For
17217 -- concurrent types, the relevant discriminant appears in the
17218 -- corresponding record. For a type derived from a private type
17219 -- without discriminant, the full view inherits the discriminants
17220 -- of the full view of the parent.
17222 if Result = Discriminant then
17223 if Is_Concurrent_Type (Ti)
17224 and then Present (Corresponding_Record_Type (Ti))
17227 Search_Derivation_Levels (
17228 Corresponding_Record_Type (Ti),
17230 Stored_Discrim_Values);
17232 elsif Is_Private_Type (Ti)
17233 and then not Has_Discriminants (Ti)
17234 and then Present (Full_View (Ti))
17235 and then Etype (Full_View (Ti)) /= Ti
17238 Search_Derivation_Levels (
17241 Stored_Discrim_Values);
17245 -- If Result is not a (reference to a) discriminant, return it,
17246 -- otherwise set Result_Entity to the discriminant.
17248 if Nkind (Result) = N_Defining_Identifier then
17249 pragma Assert (Result = Discriminant);
17250 Result_Entity := Result;
17253 if not Denotes_Discriminant (Result) then
17257 Result_Entity := Entity (Result);
17260 -- See if this level of derivation actually has discriminants because
17261 -- tagged derivations can add them, hence the lower levels need not
17264 if not Has_Discriminants (Ti) then
17268 -- Scan Ti's discriminants for Result_Entity, and return its
17269 -- corresponding value, if any.
17271 Result_Entity := Original_Record_Component (Result_Entity);
17273 Assoc := First_Elmt (Discrim_Values);
17275 if Stored_Discrim_Values then
17276 Disc := First_Stored_Discriminant (Ti);
17278 Disc := First_Discriminant (Ti);
17281 while Present (Disc) loop
17282 pragma Assert (Present (Assoc));
17284 if Original_Record_Component (Disc) = Result_Entity then
17285 return Node (Assoc);
17290 if Stored_Discrim_Values then
17291 Next_Stored_Discriminant (Disc);
17293 Next_Discriminant (Disc);
17297 -- Could not find it
17300 end Search_Derivation_Levels;
17304 Result : Node_Or_Entity_Id;
17306 -- Start of processing for Get_Discriminant_Value
17309 -- ??? This routine is a gigantic mess and will be deleted. For the
17310 -- time being just test for the trivial case before calling recurse.
17312 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
17318 D := First_Discriminant (Typ_For_Constraint);
17319 E := First_Elmt (Constraint);
17320 while Present (D) loop
17321 if Chars (D) = Chars (Discriminant) then
17325 Next_Discriminant (D);
17331 Result := Search_Derivation_Levels
17332 (Typ_For_Constraint, Constraint, False);
17334 -- ??? hack to disappear when this routine is gone
17336 if Nkind (Result) = N_Defining_Identifier then
17342 D := First_Discriminant (Typ_For_Constraint);
17343 E := First_Elmt (Constraint);
17344 while Present (D) loop
17345 if Root_Corresponding_Discriminant (D) = Discriminant then
17349 Next_Discriminant (D);
17355 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
17357 end Get_Discriminant_Value;
17359 --------------------------
17360 -- Has_Range_Constraint --
17361 --------------------------
17363 function Has_Range_Constraint (N : Node_Id) return Boolean is
17364 C : constant Node_Id := Constraint (N);
17367 if Nkind (C) = N_Range_Constraint then
17370 elsif Nkind (C) = N_Digits_Constraint then
17372 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
17373 or else Present (Range_Constraint (C));
17375 elsif Nkind (C) = N_Delta_Constraint then
17376 return Present (Range_Constraint (C));
17381 end Has_Range_Constraint;
17383 ------------------------
17384 -- Inherit_Components --
17385 ------------------------
17387 function Inherit_Components
17389 Parent_Base : Entity_Id;
17390 Derived_Base : Entity_Id;
17391 Is_Tagged : Boolean;
17392 Inherit_Discr : Boolean;
17393 Discs : Elist_Id) return Elist_Id
17395 Assoc_List : constant Elist_Id := New_Elmt_List;
17397 procedure Inherit_Component
17398 (Old_C : Entity_Id;
17399 Plain_Discrim : Boolean := False;
17400 Stored_Discrim : Boolean := False);
17401 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
17402 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
17403 -- True, Old_C is a stored discriminant. If they are both false then
17404 -- Old_C is a regular component.
17406 -----------------------
17407 -- Inherit_Component --
17408 -----------------------
17410 procedure Inherit_Component
17411 (Old_C : Entity_Id;
17412 Plain_Discrim : Boolean := False;
17413 Stored_Discrim : Boolean := False)
17415 procedure Set_Anonymous_Type (Id : Entity_Id);
17416 -- Id denotes the entity of an access discriminant or anonymous
17417 -- access component. Set the type of Id to either the same type of
17418 -- Old_C or create a new one depending on whether the parent and
17419 -- the child types are in the same scope.
17421 ------------------------
17422 -- Set_Anonymous_Type --
17423 ------------------------
17425 procedure Set_Anonymous_Type (Id : Entity_Id) is
17426 Old_Typ : constant Entity_Id := Etype (Old_C);
17429 if Scope (Parent_Base) = Scope (Derived_Base) then
17430 Set_Etype (Id, Old_Typ);
17432 -- The parent and the derived type are in two different scopes.
17433 -- Reuse the type of the original discriminant / component by
17434 -- copying it in order to preserve all attributes.
17438 Typ : constant Entity_Id := New_Copy (Old_Typ);
17441 Set_Etype (Id, Typ);
17443 -- Since we do not generate component declarations for
17444 -- inherited components, associate the itype with the
17447 Set_Associated_Node_For_Itype (Typ, Parent (Derived_Base));
17448 Set_Scope (Typ, Derived_Base);
17451 end Set_Anonymous_Type;
17453 -- Local variables and constants
17455 New_C : constant Entity_Id := New_Copy (Old_C);
17457 Corr_Discrim : Entity_Id;
17458 Discrim : Entity_Id;
17460 -- Start of processing for Inherit_Component
17463 pragma Assert (not Is_Tagged or not Stored_Discrim);
17465 Set_Parent (New_C, Parent (Old_C));
17467 -- Regular discriminants and components must be inserted in the scope
17468 -- of the Derived_Base. Do it here.
17470 if not Stored_Discrim then
17471 Enter_Name (New_C);
17474 -- For tagged types the Original_Record_Component must point to
17475 -- whatever this field was pointing to in the parent type. This has
17476 -- already been achieved by the call to New_Copy above.
17478 if not Is_Tagged then
17479 Set_Original_Record_Component (New_C, New_C);
17482 -- Set the proper type of an access discriminant
17484 if Ekind (New_C) = E_Discriminant
17485 and then Ekind (Etype (New_C)) = E_Anonymous_Access_Type
17487 Set_Anonymous_Type (New_C);
17490 -- If we have inherited a component then see if its Etype contains
17491 -- references to Parent_Base discriminants. In this case, replace
17492 -- these references with the constraints given in Discs. We do not
17493 -- do this for the partial view of private types because this is
17494 -- not needed (only the components of the full view will be used
17495 -- for code generation) and cause problem. We also avoid this
17496 -- transformation in some error situations.
17498 if Ekind (New_C) = E_Component then
17500 -- Set the proper type of an anonymous access component
17502 if Ekind (Etype (New_C)) = E_Anonymous_Access_Type then
17503 Set_Anonymous_Type (New_C);
17505 elsif (Is_Private_Type (Derived_Base)
17506 and then not Is_Generic_Type (Derived_Base))
17507 or else (Is_Empty_Elmt_List (Discs)
17508 and then not Expander_Active)
17510 Set_Etype (New_C, Etype (Old_C));
17513 -- The current component introduces a circularity of the
17516 -- limited with Pack_2;
17517 -- package Pack_1 is
17518 -- type T_1 is tagged record
17519 -- Comp : access Pack_2.T_2;
17525 -- package Pack_2 is
17526 -- type T_2 is new Pack_1.T_1 with ...;
17531 Constrain_Component_Type
17532 (Old_C, Derived_Base, N, Parent_Base, Discs));
17536 -- In derived tagged types it is illegal to reference a non
17537 -- discriminant component in the parent type. To catch this, mark
17538 -- these components with an Ekind of E_Void. This will be reset in
17539 -- Record_Type_Definition after processing the record extension of
17540 -- the derived type.
17542 -- If the declaration is a private extension, there is no further
17543 -- record extension to process, and the components retain their
17544 -- current kind, because they are visible at this point.
17546 if Is_Tagged and then Ekind (New_C) = E_Component
17547 and then Nkind (N) /= N_Private_Extension_Declaration
17549 Set_Ekind (New_C, E_Void);
17552 if Plain_Discrim then
17553 Set_Corresponding_Discriminant (New_C, Old_C);
17554 Build_Discriminal (New_C);
17556 -- If we are explicitly inheriting a stored discriminant it will be
17557 -- completely hidden.
17559 elsif Stored_Discrim then
17560 Set_Corresponding_Discriminant (New_C, Empty);
17561 Set_Discriminal (New_C, Empty);
17562 Set_Is_Completely_Hidden (New_C);
17564 -- Set the Original_Record_Component of each discriminant in the
17565 -- derived base to point to the corresponding stored that we just
17568 Discrim := First_Discriminant (Derived_Base);
17569 while Present (Discrim) loop
17570 Corr_Discrim := Corresponding_Discriminant (Discrim);
17572 -- Corr_Discrim could be missing in an error situation
17574 if Present (Corr_Discrim)
17575 and then Original_Record_Component (Corr_Discrim) = Old_C
17577 Set_Original_Record_Component (Discrim, New_C);
17580 Next_Discriminant (Discrim);
17583 Append_Entity (New_C, Derived_Base);
17586 if not Is_Tagged then
17587 Append_Elmt (Old_C, Assoc_List);
17588 Append_Elmt (New_C, Assoc_List);
17590 end Inherit_Component;
17592 -- Variables local to Inherit_Component
17594 Loc : constant Source_Ptr := Sloc (N);
17596 Parent_Discrim : Entity_Id;
17597 Stored_Discrim : Entity_Id;
17599 Component : Entity_Id;
17601 -- Start of processing for Inherit_Components
17604 if not Is_Tagged then
17605 Append_Elmt (Parent_Base, Assoc_List);
17606 Append_Elmt (Derived_Base, Assoc_List);
17609 -- Inherit parent discriminants if needed
17611 if Inherit_Discr then
17612 Parent_Discrim := First_Discriminant (Parent_Base);
17613 while Present (Parent_Discrim) loop
17614 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
17615 Next_Discriminant (Parent_Discrim);
17619 -- Create explicit stored discrims for untagged types when necessary
17621 if not Has_Unknown_Discriminants (Derived_Base)
17622 and then Has_Discriminants (Parent_Base)
17623 and then not Is_Tagged
17626 or else First_Discriminant (Parent_Base) /=
17627 First_Stored_Discriminant (Parent_Base))
17629 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
17630 while Present (Stored_Discrim) loop
17631 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
17632 Next_Stored_Discriminant (Stored_Discrim);
17636 -- See if we can apply the second transformation for derived types, as
17637 -- explained in point 6. in the comments above Build_Derived_Record_Type
17638 -- This is achieved by appending Derived_Base discriminants into Discs,
17639 -- which has the side effect of returning a non empty Discs list to the
17640 -- caller of Inherit_Components, which is what we want. This must be
17641 -- done for private derived types if there are explicit stored
17642 -- discriminants, to ensure that we can retrieve the values of the
17643 -- constraints provided in the ancestors.
17646 and then Is_Empty_Elmt_List (Discs)
17647 and then Present (First_Discriminant (Derived_Base))
17649 (not Is_Private_Type (Derived_Base)
17650 or else Is_Completely_Hidden
17651 (First_Stored_Discriminant (Derived_Base))
17652 or else Is_Generic_Type (Derived_Base))
17654 D := First_Discriminant (Derived_Base);
17655 while Present (D) loop
17656 Append_Elmt (New_Occurrence_Of (D, Loc), Discs);
17657 Next_Discriminant (D);
17661 -- Finally, inherit non-discriminant components unless they are not
17662 -- visible because defined or inherited from the full view of the
17663 -- parent. Don't inherit the _parent field of the parent type.
17665 Component := First_Entity (Parent_Base);
17666 while Present (Component) loop
17668 -- Ada 2005 (AI-251): Do not inherit components associated with
17669 -- secondary tags of the parent.
17671 if Ekind (Component) = E_Component
17672 and then Present (Related_Type (Component))
17676 elsif Ekind (Component) /= E_Component
17677 or else Chars (Component) = Name_uParent
17681 -- If the derived type is within the parent type's declarative
17682 -- region, then the components can still be inherited even though
17683 -- they aren't visible at this point. This can occur for cases
17684 -- such as within public child units where the components must
17685 -- become visible upon entering the child unit's private part.
17687 elsif not Is_Visible_Component (Component)
17688 and then not In_Open_Scopes (Scope (Parent_Base))
17692 elsif Ekind_In (Derived_Base, E_Private_Type,
17693 E_Limited_Private_Type)
17698 Inherit_Component (Component);
17701 Next_Entity (Component);
17704 -- For tagged derived types, inherited discriminants cannot be used in
17705 -- component declarations of the record extension part. To achieve this
17706 -- we mark the inherited discriminants as not visible.
17708 if Is_Tagged and then Inherit_Discr then
17709 D := First_Discriminant (Derived_Base);
17710 while Present (D) loop
17711 Set_Is_Immediately_Visible (D, False);
17712 Next_Discriminant (D);
17717 end Inherit_Components;
17719 -----------------------------
17720 -- Inherit_Predicate_Flags --
17721 -----------------------------
17723 procedure Inherit_Predicate_Flags (Subt, Par : Entity_Id) is
17725 Set_Has_Predicates (Subt, Has_Predicates (Par));
17726 Set_Has_Static_Predicate_Aspect
17727 (Subt, Has_Static_Predicate_Aspect (Par));
17728 Set_Has_Dynamic_Predicate_Aspect
17729 (Subt, Has_Dynamic_Predicate_Aspect (Par));
17730 end Inherit_Predicate_Flags;
17732 ----------------------
17733 -- Is_EVF_Procedure --
17734 ----------------------
17736 function Is_EVF_Procedure (Subp : Entity_Id) return Boolean is
17737 Formal : Entity_Id;
17740 -- Examine the formals of an Extensions_Visible False procedure looking
17741 -- for a controlling OUT parameter.
17743 if Ekind (Subp) = E_Procedure
17744 and then Extensions_Visible_Status (Subp) = Extensions_Visible_False
17746 Formal := First_Formal (Subp);
17747 while Present (Formal) loop
17748 if Ekind (Formal) = E_Out_Parameter
17749 and then Is_Controlling_Formal (Formal)
17754 Next_Formal (Formal);
17759 end Is_EVF_Procedure;
17761 -----------------------
17762 -- Is_Null_Extension --
17763 -----------------------
17765 function Is_Null_Extension (T : Entity_Id) return Boolean is
17766 Type_Decl : constant Node_Id := Parent (Base_Type (T));
17767 Comp_List : Node_Id;
17771 if Nkind (Type_Decl) /= N_Full_Type_Declaration
17772 or else not Is_Tagged_Type (T)
17773 or else Nkind (Type_Definition (Type_Decl)) /=
17774 N_Derived_Type_Definition
17775 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
17781 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
17783 if Present (Discriminant_Specifications (Type_Decl)) then
17786 elsif Present (Comp_List)
17787 and then Is_Non_Empty_List (Component_Items (Comp_List))
17789 Comp := First (Component_Items (Comp_List));
17791 -- Only user-defined components are relevant. The component list
17792 -- may also contain a parent component and internal components
17793 -- corresponding to secondary tags, but these do not determine
17794 -- whether this is a null extension.
17796 while Present (Comp) loop
17797 if Comes_From_Source (Comp) then
17809 end Is_Null_Extension;
17811 ------------------------------
17812 -- Is_Valid_Constraint_Kind --
17813 ------------------------------
17815 function Is_Valid_Constraint_Kind
17816 (T_Kind : Type_Kind;
17817 Constraint_Kind : Node_Kind) return Boolean
17821 when Enumeration_Kind |
17823 return Constraint_Kind = N_Range_Constraint;
17825 when Decimal_Fixed_Point_Kind =>
17826 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
17827 N_Range_Constraint);
17829 when Ordinary_Fixed_Point_Kind =>
17830 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
17831 N_Range_Constraint);
17834 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
17835 N_Range_Constraint);
17842 E_Incomplete_Type |
17845 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
17848 return True; -- Error will be detected later
17850 end Is_Valid_Constraint_Kind;
17852 --------------------------
17853 -- Is_Visible_Component --
17854 --------------------------
17856 function Is_Visible_Component
17858 N : Node_Id := Empty) return Boolean
17860 Original_Comp : Entity_Id := Empty;
17861 Original_Type : Entity_Id;
17862 Type_Scope : Entity_Id;
17864 function Is_Local_Type (Typ : Entity_Id) return Boolean;
17865 -- Check whether parent type of inherited component is declared locally,
17866 -- possibly within a nested package or instance. The current scope is
17867 -- the derived record itself.
17869 -------------------
17870 -- Is_Local_Type --
17871 -------------------
17873 function Is_Local_Type (Typ : Entity_Id) return Boolean is
17877 Scop := Scope (Typ);
17878 while Present (Scop)
17879 and then Scop /= Standard_Standard
17881 if Scop = Scope (Current_Scope) then
17885 Scop := Scope (Scop);
17891 -- Start of processing for Is_Visible_Component
17894 if Ekind_In (C, E_Component, E_Discriminant) then
17895 Original_Comp := Original_Record_Component (C);
17898 if No (Original_Comp) then
17900 -- Premature usage, or previous error
17905 Original_Type := Scope (Original_Comp);
17906 Type_Scope := Scope (Base_Type (Scope (C)));
17909 -- This test only concerns tagged types
17911 if not Is_Tagged_Type (Original_Type) then
17914 -- If it is _Parent or _Tag, there is no visibility issue
17916 elsif not Comes_From_Source (Original_Comp) then
17919 -- Discriminants are visible unless the (private) type has unknown
17920 -- discriminants. If the discriminant reference is inserted for a
17921 -- discriminant check on a full view it is also visible.
17923 elsif Ekind (Original_Comp) = E_Discriminant
17925 (not Has_Unknown_Discriminants (Original_Type)
17926 or else (Present (N)
17927 and then Nkind (N) = N_Selected_Component
17928 and then Nkind (Prefix (N)) = N_Type_Conversion
17929 and then not Comes_From_Source (Prefix (N))))
17933 -- In the body of an instantiation, no need to check for the visibility
17936 elsif In_Instance_Body then
17939 -- If the component has been declared in an ancestor which is currently
17940 -- a private type, then it is not visible. The same applies if the
17941 -- component's containing type is not in an open scope and the original
17942 -- component's enclosing type is a visible full view of a private type
17943 -- (which can occur in cases where an attempt is being made to reference
17944 -- a component in a sibling package that is inherited from a visible
17945 -- component of a type in an ancestor package; the component in the
17946 -- sibling package should not be visible even though the component it
17947 -- inherited from is visible). This does not apply however in the case
17948 -- where the scope of the type is a private child unit, or when the
17949 -- parent comes from a local package in which the ancestor is currently
17950 -- visible. The latter suppression of visibility is needed for cases
17951 -- that are tested in B730006.
17953 elsif Is_Private_Type (Original_Type)
17955 (not Is_Private_Descendant (Type_Scope)
17956 and then not In_Open_Scopes (Type_Scope)
17957 and then Has_Private_Declaration (Original_Type))
17959 -- If the type derives from an entity in a formal package, there
17960 -- are no additional visible components.
17962 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
17963 N_Formal_Package_Declaration
17967 -- if we are not in the private part of the current package, there
17968 -- are no additional visible components.
17970 elsif Ekind (Scope (Current_Scope)) = E_Package
17971 and then not In_Private_Part (Scope (Current_Scope))
17976 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
17977 and then In_Open_Scopes (Scope (Original_Type))
17978 and then Is_Local_Type (Type_Scope);
17981 -- There is another weird way in which a component may be invisible when
17982 -- the private and the full view are not derived from the same ancestor.
17983 -- Here is an example :
17985 -- type A1 is tagged record F1 : integer; end record;
17986 -- type A2 is new A1 with record F2 : integer; end record;
17987 -- type T is new A1 with private;
17989 -- type T is new A2 with null record;
17991 -- In this case, the full view of T inherits F1 and F2 but the private
17992 -- view inherits only F1
17996 Ancestor : Entity_Id := Scope (C);
18000 if Ancestor = Original_Type then
18003 -- The ancestor may have a partial view of the original type,
18004 -- but if the full view is in scope, as in a child body, the
18005 -- component is visible.
18007 elsif In_Private_Part (Scope (Original_Type))
18008 and then Full_View (Ancestor) = Original_Type
18012 elsif Ancestor = Etype (Ancestor) then
18014 -- No further ancestors to examine
18019 Ancestor := Etype (Ancestor);
18023 end Is_Visible_Component;
18025 --------------------------
18026 -- Make_Class_Wide_Type --
18027 --------------------------
18029 procedure Make_Class_Wide_Type (T : Entity_Id) is
18030 CW_Type : Entity_Id;
18032 Next_E : Entity_Id;
18035 if Present (Class_Wide_Type (T)) then
18037 -- The class-wide type is a partially decorated entity created for a
18038 -- unanalyzed tagged type referenced through a limited with clause.
18039 -- When the tagged type is analyzed, its class-wide type needs to be
18040 -- redecorated. Note that we reuse the entity created by Decorate_
18041 -- Tagged_Type in order to preserve all links.
18043 if Materialize_Entity (Class_Wide_Type (T)) then
18044 CW_Type := Class_Wide_Type (T);
18045 Set_Materialize_Entity (CW_Type, False);
18047 -- The class wide type can have been defined by the partial view, in
18048 -- which case everything is already done.
18054 -- Default case, we need to create a new class-wide type
18058 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
18061 -- Inherit root type characteristics
18063 CW_Name := Chars (CW_Type);
18064 Next_E := Next_Entity (CW_Type);
18065 Copy_Node (T, CW_Type);
18066 Set_Comes_From_Source (CW_Type, False);
18067 Set_Chars (CW_Type, CW_Name);
18068 Set_Parent (CW_Type, Parent (T));
18069 Set_Next_Entity (CW_Type, Next_E);
18071 -- Ensure we have a new freeze node for the class-wide type. The partial
18072 -- view may have freeze action of its own, requiring a proper freeze
18073 -- node, and the same freeze node cannot be shared between the two
18076 Set_Has_Delayed_Freeze (CW_Type);
18077 Set_Freeze_Node (CW_Type, Empty);
18079 -- Customize the class-wide type: It has no prim. op., it cannot be
18080 -- abstract and its Etype points back to the specific root type.
18082 Set_Ekind (CW_Type, E_Class_Wide_Type);
18083 Set_Is_Tagged_Type (CW_Type, True);
18084 Set_Direct_Primitive_Operations (CW_Type, New_Elmt_List);
18085 Set_Is_Abstract_Type (CW_Type, False);
18086 Set_Is_Constrained (CW_Type, False);
18087 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
18088 Set_Default_SSO (CW_Type);
18090 if Ekind (T) = E_Class_Wide_Subtype then
18091 Set_Etype (CW_Type, Etype (Base_Type (T)));
18093 Set_Etype (CW_Type, T);
18096 Set_No_Tagged_Streams_Pragma (CW_Type, No_Tagged_Streams);
18098 -- If this is the class_wide type of a constrained subtype, it does
18099 -- not have discriminants.
18101 Set_Has_Discriminants (CW_Type,
18102 Has_Discriminants (T) and then not Is_Constrained (T));
18104 Set_Has_Unknown_Discriminants (CW_Type, True);
18105 Set_Class_Wide_Type (T, CW_Type);
18106 Set_Equivalent_Type (CW_Type, Empty);
18108 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
18110 Set_Class_Wide_Type (CW_Type, CW_Type);
18112 -- Inherit the "ghostness" from the root tagged type
18114 if Ghost_Mode > None or else Is_Ghost_Entity (T) then
18115 Set_Is_Ghost_Entity (CW_Type);
18117 end Make_Class_Wide_Type;
18123 procedure Make_Index
18125 Related_Nod : Node_Id;
18126 Related_Id : Entity_Id := Empty;
18127 Suffix_Index : Nat := 1;
18128 In_Iter_Schm : Boolean := False)
18132 Def_Id : Entity_Id := Empty;
18133 Found : Boolean := False;
18136 -- For a discrete range used in a constrained array definition and
18137 -- defined by a range, an implicit conversion to the predefined type
18138 -- INTEGER is assumed if each bound is either a numeric literal, a named
18139 -- number, or an attribute, and the type of both bounds (prior to the
18140 -- implicit conversion) is the type universal_integer. Otherwise, both
18141 -- bounds must be of the same discrete type, other than universal
18142 -- integer; this type must be determinable independently of the
18143 -- context, but using the fact that the type must be discrete and that
18144 -- both bounds must have the same type.
18146 -- Character literals also have a universal type in the absence of
18147 -- of additional context, and are resolved to Standard_Character.
18149 if Nkind (N) = N_Range then
18151 -- The index is given by a range constraint. The bounds are known
18152 -- to be of a consistent type.
18154 if not Is_Overloaded (N) then
18157 -- For universal bounds, choose the specific predefined type
18159 if T = Universal_Integer then
18160 T := Standard_Integer;
18162 elsif T = Any_Character then
18163 Ambiguous_Character (Low_Bound (N));
18165 T := Standard_Character;
18168 -- The node may be overloaded because some user-defined operators
18169 -- are available, but if a universal interpretation exists it is
18170 -- also the selected one.
18172 elsif Universal_Interpretation (N) = Universal_Integer then
18173 T := Standard_Integer;
18179 Ind : Interp_Index;
18183 Get_First_Interp (N, Ind, It);
18184 while Present (It.Typ) loop
18185 if Is_Discrete_Type (It.Typ) then
18188 and then not Covers (It.Typ, T)
18189 and then not Covers (T, It.Typ)
18191 Error_Msg_N ("ambiguous bounds in discrete range", N);
18199 Get_Next_Interp (Ind, It);
18202 if T = Any_Type then
18203 Error_Msg_N ("discrete type required for range", N);
18204 Set_Etype (N, Any_Type);
18207 elsif T = Universal_Integer then
18208 T := Standard_Integer;
18213 if not Is_Discrete_Type (T) then
18214 Error_Msg_N ("discrete type required for range", N);
18215 Set_Etype (N, Any_Type);
18219 if Nkind (Low_Bound (N)) = N_Attribute_Reference
18220 and then Attribute_Name (Low_Bound (N)) = Name_First
18221 and then Is_Entity_Name (Prefix (Low_Bound (N)))
18222 and then Is_Type (Entity (Prefix (Low_Bound (N))))
18223 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (N))))
18225 -- The type of the index will be the type of the prefix, as long
18226 -- as the upper bound is 'Last of the same type.
18228 Def_Id := Entity (Prefix (Low_Bound (N)));
18230 if Nkind (High_Bound (N)) /= N_Attribute_Reference
18231 or else Attribute_Name (High_Bound (N)) /= Name_Last
18232 or else not Is_Entity_Name (Prefix (High_Bound (N)))
18233 or else Entity (Prefix (High_Bound (N))) /= Def_Id
18240 Process_Range_Expr_In_Decl (R, T, In_Iter_Schm => In_Iter_Schm);
18242 elsif Nkind (N) = N_Subtype_Indication then
18244 -- The index is given by a subtype with a range constraint
18246 T := Base_Type (Entity (Subtype_Mark (N)));
18248 if not Is_Discrete_Type (T) then
18249 Error_Msg_N ("discrete type required for range", N);
18250 Set_Etype (N, Any_Type);
18254 R := Range_Expression (Constraint (N));
18257 Process_Range_Expr_In_Decl
18258 (R, Entity (Subtype_Mark (N)), In_Iter_Schm => In_Iter_Schm);
18260 elsif Nkind (N) = N_Attribute_Reference then
18262 -- Catch beginner's error (use of attribute other than 'Range)
18264 if Attribute_Name (N) /= Name_Range then
18265 Error_Msg_N ("expect attribute ''Range", N);
18266 Set_Etype (N, Any_Type);
18270 -- If the node denotes the range of a type mark, that is also the
18271 -- resulting type, and we do not need to create an Itype for it.
18273 if Is_Entity_Name (Prefix (N))
18274 and then Comes_From_Source (N)
18275 and then Is_Type (Entity (Prefix (N)))
18276 and then Is_Discrete_Type (Entity (Prefix (N)))
18278 Def_Id := Entity (Prefix (N));
18281 Analyze_And_Resolve (N);
18285 -- If none of the above, must be a subtype. We convert this to a
18286 -- range attribute reference because in the case of declared first
18287 -- named subtypes, the types in the range reference can be different
18288 -- from the type of the entity. A range attribute normalizes the
18289 -- reference and obtains the correct types for the bounds.
18291 -- This transformation is in the nature of an expansion, is only
18292 -- done if expansion is active. In particular, it is not done on
18293 -- formal generic types, because we need to retain the name of the
18294 -- original index for instantiation purposes.
18297 if not Is_Entity_Name (N) or else not Is_Type (Entity (N)) then
18298 Error_Msg_N ("invalid subtype mark in discrete range ", N);
18299 Set_Etype (N, Any_Integer);
18303 -- The type mark may be that of an incomplete type. It is only
18304 -- now that we can get the full view, previous analysis does
18305 -- not look specifically for a type mark.
18307 Set_Entity (N, Get_Full_View (Entity (N)));
18308 Set_Etype (N, Entity (N));
18309 Def_Id := Entity (N);
18311 if not Is_Discrete_Type (Def_Id) then
18312 Error_Msg_N ("discrete type required for index", N);
18313 Set_Etype (N, Any_Type);
18318 if Expander_Active then
18320 Make_Attribute_Reference (Sloc (N),
18321 Attribute_Name => Name_Range,
18322 Prefix => Relocate_Node (N)));
18324 -- The original was a subtype mark that does not freeze. This
18325 -- means that the rewritten version must not freeze either.
18327 Set_Must_Not_Freeze (N);
18328 Set_Must_Not_Freeze (Prefix (N));
18329 Analyze_And_Resolve (N);
18333 -- If expander is inactive, type is legal, nothing else to construct
18340 if not Is_Discrete_Type (T) then
18341 Error_Msg_N ("discrete type required for range", N);
18342 Set_Etype (N, Any_Type);
18345 elsif T = Any_Type then
18346 Set_Etype (N, Any_Type);
18350 -- We will now create the appropriate Itype to describe the range, but
18351 -- first a check. If we originally had a subtype, then we just label
18352 -- the range with this subtype. Not only is there no need to construct
18353 -- a new subtype, but it is wrong to do so for two reasons:
18355 -- 1. A legality concern, if we have a subtype, it must not freeze,
18356 -- and the Itype would cause freezing incorrectly
18358 -- 2. An efficiency concern, if we created an Itype, it would not be
18359 -- recognized as the same type for the purposes of eliminating
18360 -- checks in some circumstances.
18362 -- We signal this case by setting the subtype entity in Def_Id
18364 if No (Def_Id) then
18366 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
18367 Set_Etype (Def_Id, Base_Type (T));
18369 if Is_Signed_Integer_Type (T) then
18370 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
18372 elsif Is_Modular_Integer_Type (T) then
18373 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
18376 Set_Ekind (Def_Id, E_Enumeration_Subtype);
18377 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
18378 Set_First_Literal (Def_Id, First_Literal (T));
18381 Set_Size_Info (Def_Id, (T));
18382 Set_RM_Size (Def_Id, RM_Size (T));
18383 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
18385 Set_Scalar_Range (Def_Id, R);
18386 Conditional_Delay (Def_Id, T);
18388 if Nkind (N) = N_Subtype_Indication then
18389 Inherit_Predicate_Flags (Def_Id, Entity (Subtype_Mark (N)));
18392 -- In the subtype indication case, if the immediate parent of the
18393 -- new subtype is non-static, then the subtype we create is non-
18394 -- static, even if its bounds are static.
18396 if Nkind (N) = N_Subtype_Indication
18397 and then not Is_OK_Static_Subtype (Entity (Subtype_Mark (N)))
18399 Set_Is_Non_Static_Subtype (Def_Id);
18403 -- Final step is to label the index with this constructed type
18405 Set_Etype (N, Def_Id);
18408 ------------------------------
18409 -- Modular_Type_Declaration --
18410 ------------------------------
18412 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
18413 Mod_Expr : constant Node_Id := Expression (Def);
18416 procedure Set_Modular_Size (Bits : Int);
18417 -- Sets RM_Size to Bits, and Esize to normal word size above this
18419 ----------------------
18420 -- Set_Modular_Size --
18421 ----------------------
18423 procedure Set_Modular_Size (Bits : Int) is
18425 Set_RM_Size (T, UI_From_Int (Bits));
18430 elsif Bits <= 16 then
18431 Init_Esize (T, 16);
18433 elsif Bits <= 32 then
18434 Init_Esize (T, 32);
18437 Init_Esize (T, System_Max_Binary_Modulus_Power);
18440 if not Non_Binary_Modulus (T) and then Esize (T) = RM_Size (T) then
18441 Set_Is_Known_Valid (T);
18443 end Set_Modular_Size;
18445 -- Start of processing for Modular_Type_Declaration
18448 -- If the mod expression is (exactly) 2 * literal, where literal is
18449 -- 64 or less,then almost certainly the * was meant to be **. Warn.
18451 if Warn_On_Suspicious_Modulus_Value
18452 and then Nkind (Mod_Expr) = N_Op_Multiply
18453 and then Nkind (Left_Opnd (Mod_Expr)) = N_Integer_Literal
18454 and then Intval (Left_Opnd (Mod_Expr)) = Uint_2
18455 and then Nkind (Right_Opnd (Mod_Expr)) = N_Integer_Literal
18456 and then Intval (Right_Opnd (Mod_Expr)) <= Uint_64
18459 ("suspicious MOD value, was '*'* intended'??M?", Mod_Expr);
18462 -- Proceed with analysis of mod expression
18464 Analyze_And_Resolve (Mod_Expr, Any_Integer);
18466 Set_Ekind (T, E_Modular_Integer_Type);
18467 Init_Alignment (T);
18468 Set_Is_Constrained (T);
18470 if not Is_OK_Static_Expression (Mod_Expr) then
18471 Flag_Non_Static_Expr
18472 ("non-static expression used for modular type bound!", Mod_Expr);
18473 M_Val := 2 ** System_Max_Binary_Modulus_Power;
18475 M_Val := Expr_Value (Mod_Expr);
18479 Error_Msg_N ("modulus value must be positive", Mod_Expr);
18480 M_Val := 2 ** System_Max_Binary_Modulus_Power;
18483 if M_Val > 2 ** Standard_Long_Integer_Size then
18484 Check_Restriction (No_Long_Long_Integers, Mod_Expr);
18487 Set_Modulus (T, M_Val);
18489 -- Create bounds for the modular type based on the modulus given in
18490 -- the type declaration and then analyze and resolve those bounds.
18492 Set_Scalar_Range (T,
18493 Make_Range (Sloc (Mod_Expr),
18494 Low_Bound => Make_Integer_Literal (Sloc (Mod_Expr), 0),
18495 High_Bound => Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
18497 -- Properly analyze the literals for the range. We do this manually
18498 -- because we can't go calling Resolve, since we are resolving these
18499 -- bounds with the type, and this type is certainly not complete yet.
18501 Set_Etype (Low_Bound (Scalar_Range (T)), T);
18502 Set_Etype (High_Bound (Scalar_Range (T)), T);
18503 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
18504 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
18506 -- Loop through powers of two to find number of bits required
18508 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
18512 if M_Val = 2 ** Bits then
18513 Set_Modular_Size (Bits);
18518 elsif M_Val < 2 ** Bits then
18519 Check_SPARK_05_Restriction ("modulus should be a power of 2", T);
18520 Set_Non_Binary_Modulus (T);
18522 if Bits > System_Max_Nonbinary_Modulus_Power then
18523 Error_Msg_Uint_1 :=
18524 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
18526 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
18527 Set_Modular_Size (System_Max_Binary_Modulus_Power);
18531 -- In the nonbinary case, set size as per RM 13.3(55)
18533 Set_Modular_Size (Bits);
18540 -- If we fall through, then the size exceed System.Max_Binary_Modulus
18541 -- so we just signal an error and set the maximum size.
18543 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
18544 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
18546 Set_Modular_Size (System_Max_Binary_Modulus_Power);
18547 Init_Alignment (T);
18549 end Modular_Type_Declaration;
18551 --------------------------
18552 -- New_Concatenation_Op --
18553 --------------------------
18555 procedure New_Concatenation_Op (Typ : Entity_Id) is
18556 Loc : constant Source_Ptr := Sloc (Typ);
18559 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
18560 -- Create abbreviated declaration for the formal of a predefined
18561 -- Operator 'Op' of type 'Typ'
18563 --------------------
18564 -- Make_Op_Formal --
18565 --------------------
18567 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
18568 Formal : Entity_Id;
18570 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
18571 Set_Etype (Formal, Typ);
18572 Set_Mechanism (Formal, Default_Mechanism);
18574 end Make_Op_Formal;
18576 -- Start of processing for New_Concatenation_Op
18579 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
18581 Set_Ekind (Op, E_Operator);
18582 Set_Scope (Op, Current_Scope);
18583 Set_Etype (Op, Typ);
18584 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
18585 Set_Is_Immediately_Visible (Op);
18586 Set_Is_Intrinsic_Subprogram (Op);
18587 Set_Has_Completion (Op);
18588 Append_Entity (Op, Current_Scope);
18590 Set_Name_Entity_Id (Name_Op_Concat, Op);
18592 Append_Entity (Make_Op_Formal (Typ, Op), Op);
18593 Append_Entity (Make_Op_Formal (Typ, Op), Op);
18594 end New_Concatenation_Op;
18596 -------------------------
18597 -- OK_For_Limited_Init --
18598 -------------------------
18600 -- ???Check all calls of this, and compare the conditions under which it's
18603 function OK_For_Limited_Init
18605 Exp : Node_Id) return Boolean
18608 return Is_CPP_Constructor_Call (Exp)
18609 or else (Ada_Version >= Ada_2005
18610 and then not Debug_Flag_Dot_L
18611 and then OK_For_Limited_Init_In_05 (Typ, Exp));
18612 end OK_For_Limited_Init;
18614 -------------------------------
18615 -- OK_For_Limited_Init_In_05 --
18616 -------------------------------
18618 function OK_For_Limited_Init_In_05
18620 Exp : Node_Id) return Boolean
18623 -- An object of a limited interface type can be initialized with any
18624 -- expression of a nonlimited descendant type.
18626 if Is_Class_Wide_Type (Typ)
18627 and then Is_Limited_Interface (Typ)
18628 and then not Is_Limited_Type (Etype (Exp))
18633 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
18634 -- case of limited aggregates (including extension aggregates), and
18635 -- function calls. The function call may have been given in prefixed
18636 -- notation, in which case the original node is an indexed component.
18637 -- If the function is parameterless, the original node was an explicit
18638 -- dereference. The function may also be parameterless, in which case
18639 -- the source node is just an identifier.
18641 -- A branch of a conditional expression may have been removed if the
18642 -- condition is statically known. This happens during expansion, and
18643 -- thus will not happen if previous errors were encountered. The check
18644 -- will have been performed on the chosen branch, which replaces the
18645 -- original conditional expression.
18651 case Nkind (Original_Node (Exp)) is
18652 when N_Aggregate | N_Extension_Aggregate | N_Function_Call | N_Op =>
18655 when N_Identifier =>
18656 return Present (Entity (Original_Node (Exp)))
18657 and then Ekind (Entity (Original_Node (Exp))) = E_Function;
18659 when N_Qualified_Expression =>
18661 OK_For_Limited_Init_In_05
18662 (Typ, Expression (Original_Node (Exp)));
18664 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
18665 -- with a function call, the expander has rewritten the call into an
18666 -- N_Type_Conversion node to force displacement of the pointer to
18667 -- reference the component containing the secondary dispatch table.
18668 -- Otherwise a type conversion is not a legal context.
18669 -- A return statement for a build-in-place function returning a
18670 -- synchronized type also introduces an unchecked conversion.
18672 when N_Type_Conversion |
18673 N_Unchecked_Type_Conversion =>
18674 return not Comes_From_Source (Exp)
18676 OK_For_Limited_Init_In_05
18677 (Typ, Expression (Original_Node (Exp)));
18679 when N_Indexed_Component |
18680 N_Selected_Component |
18681 N_Explicit_Dereference =>
18682 return Nkind (Exp) = N_Function_Call;
18684 -- A use of 'Input is a function call, hence allowed. Normally the
18685 -- attribute will be changed to a call, but the attribute by itself
18686 -- can occur with -gnatc.
18688 when N_Attribute_Reference =>
18689 return Attribute_Name (Original_Node (Exp)) = Name_Input;
18691 -- For a case expression, all dependent expressions must be legal
18693 when N_Case_Expression =>
18698 Alt := First (Alternatives (Original_Node (Exp)));
18699 while Present (Alt) loop
18700 if not OK_For_Limited_Init_In_05 (Typ, Expression (Alt)) then
18710 -- For an if expression, all dependent expressions must be legal
18712 when N_If_Expression =>
18714 Then_Expr : constant Node_Id :=
18715 Next (First (Expressions (Original_Node (Exp))));
18716 Else_Expr : constant Node_Id := Next (Then_Expr);
18718 return OK_For_Limited_Init_In_05 (Typ, Then_Expr)
18720 OK_For_Limited_Init_In_05 (Typ, Else_Expr);
18726 end OK_For_Limited_Init_In_05;
18728 -------------------------------------------
18729 -- Ordinary_Fixed_Point_Type_Declaration --
18730 -------------------------------------------
18732 procedure Ordinary_Fixed_Point_Type_Declaration
18736 Loc : constant Source_Ptr := Sloc (Def);
18737 Delta_Expr : constant Node_Id := Delta_Expression (Def);
18738 RRS : constant Node_Id := Real_Range_Specification (Def);
18739 Implicit_Base : Entity_Id;
18746 Check_Restriction (No_Fixed_Point, Def);
18748 -- Create implicit base type
18751 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
18752 Set_Etype (Implicit_Base, Implicit_Base);
18754 -- Analyze and process delta expression
18756 Analyze_And_Resolve (Delta_Expr, Any_Real);
18758 Check_Delta_Expression (Delta_Expr);
18759 Delta_Val := Expr_Value_R (Delta_Expr);
18761 Set_Delta_Value (Implicit_Base, Delta_Val);
18763 -- Compute default small from given delta, which is the largest power
18764 -- of two that does not exceed the given delta value.
18774 if Delta_Val < Ureal_1 then
18775 while Delta_Val < Tmp loop
18776 Tmp := Tmp / Ureal_2;
18777 Scale := Scale + 1;
18782 Tmp := Tmp * Ureal_2;
18783 exit when Tmp > Delta_Val;
18784 Scale := Scale - 1;
18788 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
18791 Set_Small_Value (Implicit_Base, Small_Val);
18793 -- If no range was given, set a dummy range
18795 if RRS <= Empty_Or_Error then
18796 Low_Val := -Small_Val;
18797 High_Val := Small_Val;
18799 -- Otherwise analyze and process given range
18803 Low : constant Node_Id := Low_Bound (RRS);
18804 High : constant Node_Id := High_Bound (RRS);
18807 Analyze_And_Resolve (Low, Any_Real);
18808 Analyze_And_Resolve (High, Any_Real);
18809 Check_Real_Bound (Low);
18810 Check_Real_Bound (High);
18812 -- Obtain and set the range
18814 Low_Val := Expr_Value_R (Low);
18815 High_Val := Expr_Value_R (High);
18817 if Low_Val > High_Val then
18818 Error_Msg_NE ("??fixed point type& has null range", Def, T);
18823 -- The range for both the implicit base and the declared first subtype
18824 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
18825 -- set a temporary range in place. Note that the bounds of the base
18826 -- type will be widened to be symmetrical and to fill the available
18827 -- bits when the type is frozen.
18829 -- We could do this with all discrete types, and probably should, but
18830 -- we absolutely have to do it for fixed-point, since the end-points
18831 -- of the range and the size are determined by the small value, which
18832 -- could be reset before the freeze point.
18834 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
18835 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
18837 -- Complete definition of first subtype. The inheritance of the rep item
18838 -- chain ensures that SPARK-related pragmas are not clobbered when the
18839 -- ordinary fixed point type acts as a full view of a private type.
18841 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
18842 Set_Etype (T, Implicit_Base);
18843 Init_Size_Align (T);
18844 Inherit_Rep_Item_Chain (T, Implicit_Base);
18845 Set_Small_Value (T, Small_Val);
18846 Set_Delta_Value (T, Delta_Val);
18847 Set_Is_Constrained (T);
18848 end Ordinary_Fixed_Point_Type_Declaration;
18850 ----------------------------------
18851 -- Preanalyze_Assert_Expression --
18852 ----------------------------------
18854 procedure Preanalyze_Assert_Expression (N : Node_Id; T : Entity_Id) is
18856 In_Assertion_Expr := In_Assertion_Expr + 1;
18857 Preanalyze_Spec_Expression (N, T);
18858 In_Assertion_Expr := In_Assertion_Expr - 1;
18859 end Preanalyze_Assert_Expression;
18861 -----------------------------------
18862 -- Preanalyze_Default_Expression --
18863 -----------------------------------
18865 procedure Preanalyze_Default_Expression (N : Node_Id; T : Entity_Id) is
18866 Save_In_Default_Expr : constant Boolean := In_Default_Expr;
18868 In_Default_Expr := True;
18869 Preanalyze_Spec_Expression (N, T);
18870 In_Default_Expr := Save_In_Default_Expr;
18871 end Preanalyze_Default_Expression;
18873 --------------------------------
18874 -- Preanalyze_Spec_Expression --
18875 --------------------------------
18877 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
18878 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
18880 In_Spec_Expression := True;
18881 Preanalyze_And_Resolve (N, T);
18882 In_Spec_Expression := Save_In_Spec_Expression;
18883 end Preanalyze_Spec_Expression;
18885 ----------------------------------------
18886 -- Prepare_Private_Subtype_Completion --
18887 ----------------------------------------
18889 procedure Prepare_Private_Subtype_Completion
18891 Related_Nod : Node_Id)
18893 Id_B : constant Entity_Id := Base_Type (Id);
18894 Full_B : Entity_Id := Full_View (Id_B);
18898 if Present (Full_B) then
18900 -- Get to the underlying full view if necessary
18902 if Is_Private_Type (Full_B)
18903 and then Present (Underlying_Full_View (Full_B))
18905 Full_B := Underlying_Full_View (Full_B);
18908 -- The Base_Type is already completed, we can complete the subtype
18909 -- now. We have to create a new entity with the same name, Thus we
18910 -- can't use Create_Itype.
18912 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
18913 Set_Is_Itype (Full);
18914 Set_Associated_Node_For_Itype (Full, Related_Nod);
18915 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
18918 -- The parent subtype may be private, but the base might not, in some
18919 -- nested instances. In that case, the subtype does not need to be
18920 -- exchanged. It would still be nice to make private subtypes and their
18921 -- bases consistent at all times ???
18923 if Is_Private_Type (Id_B) then
18924 Append_Elmt (Id, Private_Dependents (Id_B));
18926 end Prepare_Private_Subtype_Completion;
18928 ---------------------------
18929 -- Process_Discriminants --
18930 ---------------------------
18932 procedure Process_Discriminants
18934 Prev : Entity_Id := Empty)
18936 Elist : constant Elist_Id := New_Elmt_List;
18939 Discr_Number : Uint;
18940 Discr_Type : Entity_Id;
18941 Default_Present : Boolean := False;
18942 Default_Not_Present : Boolean := False;
18945 -- A composite type other than an array type can have discriminants.
18946 -- On entry, the current scope is the composite type.
18948 -- The discriminants are initially entered into the scope of the type
18949 -- via Enter_Name with the default Ekind of E_Void to prevent premature
18950 -- use, as explained at the end of this procedure.
18952 Discr := First (Discriminant_Specifications (N));
18953 while Present (Discr) loop
18954 Enter_Name (Defining_Identifier (Discr));
18956 -- For navigation purposes we add a reference to the discriminant
18957 -- in the entity for the type. If the current declaration is a
18958 -- completion, place references on the partial view. Otherwise the
18959 -- type is the current scope.
18961 if Present (Prev) then
18963 -- The references go on the partial view, if present. If the
18964 -- partial view has discriminants, the references have been
18965 -- generated already.
18967 if not Has_Discriminants (Prev) then
18968 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
18972 (Current_Scope, Defining_Identifier (Discr), 'd');
18975 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
18976 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
18978 -- Ada 2005 (AI-254)
18980 if Present (Access_To_Subprogram_Definition
18981 (Discriminant_Type (Discr)))
18982 and then Protected_Present (Access_To_Subprogram_Definition
18983 (Discriminant_Type (Discr)))
18986 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
18990 Find_Type (Discriminant_Type (Discr));
18991 Discr_Type := Etype (Discriminant_Type (Discr));
18993 if Error_Posted (Discriminant_Type (Discr)) then
18994 Discr_Type := Any_Type;
18998 -- Handling of discriminants that are access types
19000 if Is_Access_Type (Discr_Type) then
19002 -- Ada 2005 (AI-230): Access discriminant allowed in non-
19003 -- limited record types
19005 if Ada_Version < Ada_2005 then
19006 Check_Access_Discriminant_Requires_Limited
19007 (Discr, Discriminant_Type (Discr));
19010 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
19012 ("(Ada 83) access discriminant not allowed", Discr);
19015 -- If not access type, must be a discrete type
19017 elsif not Is_Discrete_Type (Discr_Type) then
19019 ("discriminants must have a discrete or access type",
19020 Discriminant_Type (Discr));
19023 Set_Etype (Defining_Identifier (Discr), Discr_Type);
19025 -- If a discriminant specification includes the assignment compound
19026 -- delimiter followed by an expression, the expression is the default
19027 -- expression of the discriminant; the default expression must be of
19028 -- the type of the discriminant. (RM 3.7.1) Since this expression is
19029 -- a default expression, we do the special preanalysis, since this
19030 -- expression does not freeze (see section "Handling of Default and
19031 -- Per-Object Expressions" in spec of package Sem).
19033 if Present (Expression (Discr)) then
19034 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
19038 if Nkind (N) = N_Formal_Type_Declaration then
19040 ("discriminant defaults not allowed for formal type",
19041 Expression (Discr));
19043 -- Flag an error for a tagged type with defaulted discriminants,
19044 -- excluding limited tagged types when compiling for Ada 2012
19045 -- (see AI05-0214).
19047 elsif Is_Tagged_Type (Current_Scope)
19048 and then (not Is_Limited_Type (Current_Scope)
19049 or else Ada_Version < Ada_2012)
19050 and then Comes_From_Source (N)
19052 -- Note: see similar test in Check_Or_Process_Discriminants, to
19053 -- handle the (illegal) case of the completion of an untagged
19054 -- view with discriminants with defaults by a tagged full view.
19055 -- We skip the check if Discr does not come from source, to
19056 -- account for the case of an untagged derived type providing
19057 -- defaults for a renamed discriminant from a private untagged
19058 -- ancestor with a tagged full view (ACATS B460006).
19060 if Ada_Version >= Ada_2012 then
19062 ("discriminants of nonlimited tagged type cannot have"
19064 Expression (Discr));
19067 ("discriminants of tagged type cannot have defaults",
19068 Expression (Discr));
19072 Default_Present := True;
19073 Append_Elmt (Expression (Discr), Elist);
19075 -- Tag the defining identifiers for the discriminants with
19076 -- their corresponding default expressions from the tree.
19078 Set_Discriminant_Default_Value
19079 (Defining_Identifier (Discr), Expression (Discr));
19082 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag
19083 -- gets set unless we can be sure that no range check is required.
19085 if (GNATprove_Mode or not Expander_Active)
19088 (Expression (Discr), Discr_Type, Assume_Valid => True)
19090 Set_Do_Range_Check (Expression (Discr));
19093 -- No default discriminant value given
19096 Default_Not_Present := True;
19099 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
19100 -- Discr_Type but with the null-exclusion attribute
19102 if Ada_Version >= Ada_2005 then
19104 -- Ada 2005 (AI-231): Static checks
19106 if Can_Never_Be_Null (Discr_Type) then
19107 Null_Exclusion_Static_Checks (Discr);
19109 elsif Is_Access_Type (Discr_Type)
19110 and then Null_Exclusion_Present (Discr)
19112 -- No need to check itypes because in their case this check
19113 -- was done at their point of creation
19115 and then not Is_Itype (Discr_Type)
19117 if Can_Never_Be_Null (Discr_Type) then
19119 ("`NOT NULL` not allowed (& already excludes null)",
19124 Set_Etype (Defining_Identifier (Discr),
19125 Create_Null_Excluding_Itype
19127 Related_Nod => Discr));
19129 -- Check for improper null exclusion if the type is otherwise
19130 -- legal for a discriminant.
19132 elsif Null_Exclusion_Present (Discr)
19133 and then Is_Discrete_Type (Discr_Type)
19136 ("null exclusion can only apply to an access type", Discr);
19139 -- Ada 2005 (AI-402): access discriminants of nonlimited types
19140 -- can't have defaults. Synchronized types, or types that are
19141 -- explicitly limited are fine, but special tests apply to derived
19142 -- types in generics: in a generic body we have to assume the
19143 -- worst, and therefore defaults are not allowed if the parent is
19144 -- a generic formal private type (see ACATS B370001).
19146 if Is_Access_Type (Discr_Type) and then Default_Present then
19147 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
19148 or else Is_Limited_Record (Current_Scope)
19149 or else Is_Concurrent_Type (Current_Scope)
19150 or else Is_Concurrent_Record_Type (Current_Scope)
19151 or else Ekind (Current_Scope) = E_Limited_Private_Type
19153 if not Is_Derived_Type (Current_Scope)
19154 or else not Is_Generic_Type (Etype (Current_Scope))
19155 or else not In_Package_Body (Scope (Etype (Current_Scope)))
19156 or else Limited_Present
19157 (Type_Definition (Parent (Current_Scope)))
19163 ("access discriminants of nonlimited types cannot "
19164 & "have defaults", Expression (Discr));
19167 elsif Present (Expression (Discr)) then
19169 ("(Ada 2005) access discriminants of nonlimited types "
19170 & "cannot have defaults", Expression (Discr));
19175 -- A discriminant cannot be effectively volatile (SPARK RM 7.1.3(6)).
19176 -- This check is relevant only when SPARK_Mode is on as it is not a
19177 -- standard Ada legality rule.
19180 and then Is_Effectively_Volatile (Defining_Identifier (Discr))
19182 Error_Msg_N ("discriminant cannot be volatile", Discr);
19188 -- An element list consisting of the default expressions of the
19189 -- discriminants is constructed in the above loop and used to set
19190 -- the Discriminant_Constraint attribute for the type. If an object
19191 -- is declared of this (record or task) type without any explicit
19192 -- discriminant constraint given, this element list will form the
19193 -- actual parameters for the corresponding initialization procedure
19196 Set_Discriminant_Constraint (Current_Scope, Elist);
19197 Set_Stored_Constraint (Current_Scope, No_Elist);
19199 -- Default expressions must be provided either for all or for none
19200 -- of the discriminants of a discriminant part. (RM 3.7.1)
19202 if Default_Present and then Default_Not_Present then
19204 ("incomplete specification of defaults for discriminants", N);
19207 -- The use of the name of a discriminant is not allowed in default
19208 -- expressions of a discriminant part if the specification of the
19209 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
19211 -- To detect this, the discriminant names are entered initially with an
19212 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
19213 -- attempt to use a void entity (for example in an expression that is
19214 -- type-checked) produces the error message: premature usage. Now after
19215 -- completing the semantic analysis of the discriminant part, we can set
19216 -- the Ekind of all the discriminants appropriately.
19218 Discr := First (Discriminant_Specifications (N));
19219 Discr_Number := Uint_1;
19220 while Present (Discr) loop
19221 Id := Defining_Identifier (Discr);
19222 Set_Ekind (Id, E_Discriminant);
19223 Init_Component_Location (Id);
19225 Set_Discriminant_Number (Id, Discr_Number);
19227 -- Make sure this is always set, even in illegal programs
19229 Set_Corresponding_Discriminant (Id, Empty);
19231 -- Initialize the Original_Record_Component to the entity itself.
19232 -- Inherit_Components will propagate the right value to
19233 -- discriminants in derived record types.
19235 Set_Original_Record_Component (Id, Id);
19237 -- Create the discriminal for the discriminant
19239 Build_Discriminal (Id);
19242 Discr_Number := Discr_Number + 1;
19245 Set_Has_Discriminants (Current_Scope);
19246 end Process_Discriminants;
19248 -----------------------
19249 -- Process_Full_View --
19250 -----------------------
19252 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
19253 procedure Collect_Implemented_Interfaces
19255 Ifaces : Elist_Id);
19256 -- Ada 2005: Gather all the interfaces that Typ directly or
19257 -- inherently implements. Duplicate entries are not added to
19258 -- the list Ifaces.
19260 ------------------------------------
19261 -- Collect_Implemented_Interfaces --
19262 ------------------------------------
19264 procedure Collect_Implemented_Interfaces
19269 Iface_Elmt : Elmt_Id;
19272 -- Abstract interfaces are only associated with tagged record types
19274 if not Is_Tagged_Type (Typ) or else not Is_Record_Type (Typ) then
19278 -- Recursively climb to the ancestors
19280 if Etype (Typ) /= Typ
19282 -- Protect the frontend against wrong cyclic declarations like:
19284 -- type B is new A with private;
19285 -- type C is new A with private;
19287 -- type B is new C with null record;
19288 -- type C is new B with null record;
19290 and then Etype (Typ) /= Priv_T
19291 and then Etype (Typ) /= Full_T
19293 -- Keep separate the management of private type declarations
19295 if Ekind (Typ) = E_Record_Type_With_Private then
19297 -- Handle the following illegal usage:
19298 -- type Private_Type is tagged private;
19300 -- type Private_Type is new Type_Implementing_Iface;
19302 if Present (Full_View (Typ))
19303 and then Etype (Typ) /= Full_View (Typ)
19305 if Is_Interface (Etype (Typ)) then
19306 Append_Unique_Elmt (Etype (Typ), Ifaces);
19309 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
19312 -- Non-private types
19315 if Is_Interface (Etype (Typ)) then
19316 Append_Unique_Elmt (Etype (Typ), Ifaces);
19319 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
19323 -- Handle entities in the list of abstract interfaces
19325 if Present (Interfaces (Typ)) then
19326 Iface_Elmt := First_Elmt (Interfaces (Typ));
19327 while Present (Iface_Elmt) loop
19328 Iface := Node (Iface_Elmt);
19330 pragma Assert (Is_Interface (Iface));
19332 if not Contain_Interface (Iface, Ifaces) then
19333 Append_Elmt (Iface, Ifaces);
19334 Collect_Implemented_Interfaces (Iface, Ifaces);
19337 Next_Elmt (Iface_Elmt);
19340 end Collect_Implemented_Interfaces;
19344 Full_Indic : Node_Id;
19345 Full_Parent : Entity_Id;
19346 Priv_Parent : Entity_Id;
19348 -- Start of processing for Process_Full_View
19351 -- First some sanity checks that must be done after semantic
19352 -- decoration of the full view and thus cannot be placed with other
19353 -- similar checks in Find_Type_Name
19355 if not Is_Limited_Type (Priv_T)
19356 and then (Is_Limited_Type (Full_T)
19357 or else Is_Limited_Composite (Full_T))
19359 if In_Instance then
19363 ("completion of nonlimited type cannot be limited", Full_T);
19364 Explain_Limited_Type (Full_T, Full_T);
19367 elsif Is_Abstract_Type (Full_T)
19368 and then not Is_Abstract_Type (Priv_T)
19371 ("completion of nonabstract type cannot be abstract", Full_T);
19373 elsif Is_Tagged_Type (Priv_T)
19374 and then Is_Limited_Type (Priv_T)
19375 and then not Is_Limited_Type (Full_T)
19377 -- If pragma CPP_Class was applied to the private declaration
19378 -- propagate the limitedness to the full-view
19380 if Is_CPP_Class (Priv_T) then
19381 Set_Is_Limited_Record (Full_T);
19383 -- GNAT allow its own definition of Limited_Controlled to disobey
19384 -- this rule in order in ease the implementation. This test is safe
19385 -- because Root_Controlled is defined in a child of System that
19386 -- normal programs are not supposed to use.
19388 elsif Is_RTE (Etype (Full_T), RE_Root_Controlled) then
19389 Set_Is_Limited_Composite (Full_T);
19392 ("completion of limited tagged type must be limited", Full_T);
19395 elsif Is_Generic_Type (Priv_T) then
19396 Error_Msg_N ("generic type cannot have a completion", Full_T);
19399 -- Check that ancestor interfaces of private and full views are
19400 -- consistent. We omit this check for synchronized types because
19401 -- they are performed on the corresponding record type when frozen.
19403 if Ada_Version >= Ada_2005
19404 and then Is_Tagged_Type (Priv_T)
19405 and then Is_Tagged_Type (Full_T)
19406 and then not Is_Concurrent_Type (Full_T)
19410 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
19411 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
19414 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
19415 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
19417 -- Ada 2005 (AI-251): The partial view shall be a descendant of
19418 -- an interface type if and only if the full type is descendant
19419 -- of the interface type (AARM 7.3 (7.3/2)).
19421 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
19423 if Present (Iface) then
19425 ("interface in partial view& not implemented by full type "
19426 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
19429 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
19431 if Present (Iface) then
19433 ("interface & not implemented by partial view "
19434 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
19439 if Is_Tagged_Type (Priv_T)
19440 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19441 and then Is_Derived_Type (Full_T)
19443 Priv_Parent := Etype (Priv_T);
19445 -- The full view of a private extension may have been transformed
19446 -- into an unconstrained derived type declaration and a subtype
19447 -- declaration (see build_derived_record_type for details).
19449 if Nkind (N) = N_Subtype_Declaration then
19450 Full_Indic := Subtype_Indication (N);
19451 Full_Parent := Etype (Base_Type (Full_T));
19453 Full_Indic := Subtype_Indication (Type_Definition (N));
19454 Full_Parent := Etype (Full_T);
19457 -- Check that the parent type of the full type is a descendant of
19458 -- the ancestor subtype given in the private extension. If either
19459 -- entity has an Etype equal to Any_Type then we had some previous
19460 -- error situation [7.3(8)].
19462 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
19465 -- Ada 2005 (AI-251): Interfaces in the full type can be given in
19466 -- any order. Therefore we don't have to check that its parent must
19467 -- be a descendant of the parent of the private type declaration.
19469 elsif Is_Interface (Priv_Parent)
19470 and then Is_Interface (Full_Parent)
19474 -- Ada 2005 (AI-251): If the parent of the private type declaration
19475 -- is an interface there is no need to check that it is an ancestor
19476 -- of the associated full type declaration. The required tests for
19477 -- this case are performed by Build_Derived_Record_Type.
19479 elsif not Is_Interface (Base_Type (Priv_Parent))
19480 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
19483 ("parent of full type must descend from parent"
19484 & " of private extension", Full_Indic);
19486 -- First check a formal restriction, and then proceed with checking
19487 -- Ada rules. Since the formal restriction is not a serious error, we
19488 -- don't prevent further error detection for this check, hence the
19492 -- In formal mode, when completing a private extension the type
19493 -- named in the private part must be exactly the same as that
19494 -- named in the visible part.
19496 if Priv_Parent /= Full_Parent then
19497 Error_Msg_Name_1 := Chars (Priv_Parent);
19498 Check_SPARK_05_Restriction ("% expected", Full_Indic);
19501 -- Check the rules of 7.3(10): if the private extension inherits
19502 -- known discriminants, then the full type must also inherit those
19503 -- discriminants from the same (ancestor) type, and the parent
19504 -- subtype of the full type must be constrained if and only if
19505 -- the ancestor subtype of the private extension is constrained.
19507 if No (Discriminant_Specifications (Parent (Priv_T)))
19508 and then not Has_Unknown_Discriminants (Priv_T)
19509 and then Has_Discriminants (Base_Type (Priv_Parent))
19512 Priv_Indic : constant Node_Id :=
19513 Subtype_Indication (Parent (Priv_T));
19515 Priv_Constr : constant Boolean :=
19516 Is_Constrained (Priv_Parent)
19518 Nkind (Priv_Indic) = N_Subtype_Indication
19520 Is_Constrained (Entity (Priv_Indic));
19522 Full_Constr : constant Boolean :=
19523 Is_Constrained (Full_Parent)
19525 Nkind (Full_Indic) = N_Subtype_Indication
19527 Is_Constrained (Entity (Full_Indic));
19529 Priv_Discr : Entity_Id;
19530 Full_Discr : Entity_Id;
19533 Priv_Discr := First_Discriminant (Priv_Parent);
19534 Full_Discr := First_Discriminant (Full_Parent);
19535 while Present (Priv_Discr) and then Present (Full_Discr) loop
19536 if Original_Record_Component (Priv_Discr) =
19537 Original_Record_Component (Full_Discr)
19539 Corresponding_Discriminant (Priv_Discr) =
19540 Corresponding_Discriminant (Full_Discr)
19547 Next_Discriminant (Priv_Discr);
19548 Next_Discriminant (Full_Discr);
19551 if Present (Priv_Discr) or else Present (Full_Discr) then
19553 ("full view must inherit discriminants of the parent"
19554 & " type used in the private extension", Full_Indic);
19556 elsif Priv_Constr and then not Full_Constr then
19558 ("parent subtype of full type must be constrained",
19561 elsif Full_Constr and then not Priv_Constr then
19563 ("parent subtype of full type must be unconstrained",
19568 -- Check the rules of 7.3(12): if a partial view has neither
19569 -- known or unknown discriminants, then the full type
19570 -- declaration shall define a definite subtype.
19572 elsif not Has_Unknown_Discriminants (Priv_T)
19573 and then not Has_Discriminants (Priv_T)
19574 and then not Is_Constrained (Full_T)
19577 ("full view must define a constrained type if partial view"
19578 & " has no discriminants", Full_T);
19581 -- ??????? Do we implement the following properly ?????
19582 -- If the ancestor subtype of a private extension has constrained
19583 -- discriminants, then the parent subtype of the full view shall
19584 -- impose a statically matching constraint on those discriminants
19589 -- For untagged types, verify that a type without discriminants is
19590 -- not completed with an unconstrained type. A separate error message
19591 -- is produced if the full type has defaulted discriminants.
19593 if Is_Definite_Subtype (Priv_T)
19594 and then not Is_Definite_Subtype (Full_T)
19596 Error_Msg_Sloc := Sloc (Parent (Priv_T));
19598 ("full view of& not compatible with declaration#",
19601 if not Is_Tagged_Type (Full_T) then
19603 ("\one is constrained, the other unconstrained", Full_T);
19608 -- AI-419: verify that the use of "limited" is consistent
19611 Orig_Decl : constant Node_Id := Original_Node (N);
19614 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19615 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
19617 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
19619 if not Limited_Present (Parent (Priv_T))
19620 and then not Synchronized_Present (Parent (Priv_T))
19621 and then Limited_Present (Type_Definition (Orig_Decl))
19624 ("full view of non-limited extension cannot be limited", N);
19626 -- Conversely, if the partial view carries the limited keyword,
19627 -- the full view must as well, even if it may be redundant.
19629 elsif Limited_Present (Parent (Priv_T))
19630 and then not Limited_Present (Type_Definition (Orig_Decl))
19633 ("full view of limited extension must be explicitly limited",
19639 -- Ada 2005 (AI-443): A synchronized private extension must be
19640 -- completed by a task or protected type.
19642 if Ada_Version >= Ada_2005
19643 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19644 and then Synchronized_Present (Parent (Priv_T))
19645 and then not Is_Concurrent_Type (Full_T)
19647 Error_Msg_N ("full view of synchronized extension must " &
19648 "be synchronized type", N);
19651 -- Ada 2005 AI-363: if the full view has discriminants with
19652 -- defaults, it is illegal to declare constrained access subtypes
19653 -- whose designated type is the current type. This allows objects
19654 -- of the type that are declared in the heap to be unconstrained.
19656 if not Has_Unknown_Discriminants (Priv_T)
19657 and then not Has_Discriminants (Priv_T)
19658 and then Has_Discriminants (Full_T)
19660 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
19662 Set_Has_Constrained_Partial_View (Full_T);
19663 Set_Has_Constrained_Partial_View (Priv_T);
19666 -- Create a full declaration for all its subtypes recorded in
19667 -- Private_Dependents and swap them similarly to the base type. These
19668 -- are subtypes that have been define before the full declaration of
19669 -- the private type. We also swap the entry in Private_Dependents list
19670 -- so we can properly restore the private view on exit from the scope.
19673 Priv_Elmt : Elmt_Id;
19674 Priv_Scop : Entity_Id;
19679 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
19680 while Present (Priv_Elmt) loop
19681 Priv := Node (Priv_Elmt);
19682 Priv_Scop := Scope (Priv);
19684 if Ekind_In (Priv, E_Private_Subtype,
19685 E_Limited_Private_Subtype,
19686 E_Record_Subtype_With_Private)
19688 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
19689 Set_Is_Itype (Full);
19690 Set_Parent (Full, Parent (Priv));
19691 Set_Associated_Node_For_Itype (Full, N);
19693 -- Now we need to complete the private subtype, but since the
19694 -- base type has already been swapped, we must also swap the
19695 -- subtypes (and thus, reverse the arguments in the call to
19696 -- Complete_Private_Subtype). Also note that we may need to
19697 -- re-establish the scope of the private subtype.
19699 Copy_And_Swap (Priv, Full);
19701 if not In_Open_Scopes (Priv_Scop) then
19702 Push_Scope (Priv_Scop);
19705 -- Reset Priv_Scop to Empty to indicate no scope was pushed
19707 Priv_Scop := Empty;
19710 Complete_Private_Subtype (Full, Priv, Full_T, N);
19712 if Present (Priv_Scop) then
19716 Replace_Elmt (Priv_Elmt, Full);
19719 Next_Elmt (Priv_Elmt);
19723 -- If the private view was tagged, copy the new primitive operations
19724 -- from the private view to the full view.
19726 if Is_Tagged_Type (Full_T) then
19728 Disp_Typ : Entity_Id;
19729 Full_List : Elist_Id;
19731 Prim_Elmt : Elmt_Id;
19732 Priv_List : Elist_Id;
19736 L : Elist_Id) return Boolean;
19737 -- Determine whether list L contains element E
19745 L : Elist_Id) return Boolean
19747 List_Elmt : Elmt_Id;
19750 List_Elmt := First_Elmt (L);
19751 while Present (List_Elmt) loop
19752 if Node (List_Elmt) = E then
19756 Next_Elmt (List_Elmt);
19762 -- Start of processing
19765 if Is_Tagged_Type (Priv_T) then
19766 Priv_List := Primitive_Operations (Priv_T);
19767 Prim_Elmt := First_Elmt (Priv_List);
19769 -- In the case of a concurrent type completing a private tagged
19770 -- type, primitives may have been declared in between the two
19771 -- views. These subprograms need to be wrapped the same way
19772 -- entries and protected procedures are handled because they
19773 -- cannot be directly shared by the two views.
19775 if Is_Concurrent_Type (Full_T) then
19777 Conc_Typ : constant Entity_Id :=
19778 Corresponding_Record_Type (Full_T);
19779 Curr_Nod : Node_Id := Parent (Conc_Typ);
19780 Wrap_Spec : Node_Id;
19783 while Present (Prim_Elmt) loop
19784 Prim := Node (Prim_Elmt);
19786 if Comes_From_Source (Prim)
19787 and then not Is_Abstract_Subprogram (Prim)
19790 Make_Subprogram_Declaration (Sloc (Prim),
19794 Obj_Typ => Conc_Typ,
19796 Parameter_Specifications (
19799 Insert_After (Curr_Nod, Wrap_Spec);
19800 Curr_Nod := Wrap_Spec;
19802 Analyze (Wrap_Spec);
19805 Next_Elmt (Prim_Elmt);
19811 -- For non-concurrent types, transfer explicit primitives, but
19812 -- omit those inherited from the parent of the private view
19813 -- since they will be re-inherited later on.
19816 Full_List := Primitive_Operations (Full_T);
19818 while Present (Prim_Elmt) loop
19819 Prim := Node (Prim_Elmt);
19821 if Comes_From_Source (Prim)
19822 and then not Contains (Prim, Full_List)
19824 Append_Elmt (Prim, Full_List);
19827 Next_Elmt (Prim_Elmt);
19831 -- Untagged private view
19834 Full_List := Primitive_Operations (Full_T);
19836 -- In this case the partial view is untagged, so here we locate
19837 -- all of the earlier primitives that need to be treated as
19838 -- dispatching (those that appear between the two views). Note
19839 -- that these additional operations must all be new operations
19840 -- (any earlier operations that override inherited operations
19841 -- of the full view will already have been inserted in the
19842 -- primitives list, marked by Check_Operation_From_Private_View
19843 -- as dispatching. Note that implicit "/=" operators are
19844 -- excluded from being added to the primitives list since they
19845 -- shouldn't be treated as dispatching (tagged "/=" is handled
19848 Prim := Next_Entity (Full_T);
19849 while Present (Prim) and then Prim /= Priv_T loop
19850 if Ekind_In (Prim, E_Procedure, E_Function) then
19851 Disp_Typ := Find_Dispatching_Type (Prim);
19853 if Disp_Typ = Full_T
19854 and then (Chars (Prim) /= Name_Op_Ne
19855 or else Comes_From_Source (Prim))
19857 Check_Controlling_Formals (Full_T, Prim);
19859 if not Is_Dispatching_Operation (Prim) then
19860 Append_Elmt (Prim, Full_List);
19861 Set_Is_Dispatching_Operation (Prim, True);
19862 Set_DT_Position_Value (Prim, No_Uint);
19865 elsif Is_Dispatching_Operation (Prim)
19866 and then Disp_Typ /= Full_T
19869 -- Verify that it is not otherwise controlled by a
19870 -- formal or a return value of type T.
19872 Check_Controlling_Formals (Disp_Typ, Prim);
19876 Next_Entity (Prim);
19880 -- For the tagged case, the two views can share the same primitive
19881 -- operations list and the same class-wide type. Update attributes
19882 -- of the class-wide type which depend on the full declaration.
19884 if Is_Tagged_Type (Priv_T) then
19885 Set_Direct_Primitive_Operations (Priv_T, Full_List);
19886 Set_Class_Wide_Type
19887 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
19889 Set_Has_Task (Class_Wide_Type (Priv_T), Has_Task (Full_T));
19891 (Class_Wide_Type (Priv_T), Has_Protected (Full_T));
19896 -- Ada 2005 AI 161: Check preelaborable initialization consistency
19898 if Known_To_Have_Preelab_Init (Priv_T) then
19900 -- Case where there is a pragma Preelaborable_Initialization. We
19901 -- always allow this in predefined units, which is cheating a bit,
19902 -- but it means we don't have to struggle to meet the requirements in
19903 -- the RM for having Preelaborable Initialization. Otherwise we
19904 -- require that the type meets the RM rules. But we can't check that
19905 -- yet, because of the rule about overriding Initialize, so we simply
19906 -- set a flag that will be checked at freeze time.
19908 if not In_Predefined_Unit (Full_T) then
19909 Set_Must_Have_Preelab_Init (Full_T);
19913 -- If pragma CPP_Class was applied to the private type declaration,
19914 -- propagate it now to the full type declaration.
19916 if Is_CPP_Class (Priv_T) then
19917 Set_Is_CPP_Class (Full_T);
19918 Set_Convention (Full_T, Convention_CPP);
19920 -- Check that components of imported CPP types do not have default
19923 Check_CPP_Type_Has_No_Defaults (Full_T);
19926 -- If the private view has user specified stream attributes, then so has
19929 -- Why the test, how could these flags be already set in Full_T ???
19931 if Has_Specified_Stream_Read (Priv_T) then
19932 Set_Has_Specified_Stream_Read (Full_T);
19935 if Has_Specified_Stream_Write (Priv_T) then
19936 Set_Has_Specified_Stream_Write (Full_T);
19939 if Has_Specified_Stream_Input (Priv_T) then
19940 Set_Has_Specified_Stream_Input (Full_T);
19943 if Has_Specified_Stream_Output (Priv_T) then
19944 Set_Has_Specified_Stream_Output (Full_T);
19947 -- Propagate the attributes related to pragma Default_Initial_Condition
19948 -- from the private to the full view. Note that both flags are mutually
19951 if Has_Default_Init_Cond (Priv_T)
19952 or else Has_Inherited_Default_Init_Cond (Priv_T)
19954 Propagate_Default_Init_Cond_Attributes
19955 (From_Typ => Priv_T,
19957 Private_To_Full_View => True);
19959 -- In the case where the full view is derived from another private type,
19960 -- the attributes related to pragma Default_Initial_Condition must be
19961 -- propagated from the full to the private view to maintain consistency
19965 -- type Parent_Typ is private
19966 -- with Default_Initial_Condition ...;
19968 -- type Parent_Typ is ...;
19971 -- with Pack; use Pack;
19972 -- package Pack_2 is
19973 -- type Deriv_Typ is private; -- must inherit
19975 -- type Deriv_Typ is new Parent_Typ; -- must inherit
19978 elsif Has_Default_Init_Cond (Full_T)
19979 or else Has_Inherited_Default_Init_Cond (Full_T)
19981 Propagate_Default_Init_Cond_Attributes
19982 (From_Typ => Full_T,
19984 Private_To_Full_View => True);
19987 if Is_Ghost_Entity (Priv_T) then
19989 -- The Ghost policy in effect at the point of declaration and at the
19990 -- point of completion must match (SPARK RM 6.9(14)).
19992 Check_Ghost_Completion (Priv_T, Full_T);
19994 -- Propagate the attributes related to pragma Ghost from the private
19995 -- to the full view.
19997 Mark_Full_View_As_Ghost (Priv_T, Full_T);
20000 -- Propagate invariants to full type
20002 if Has_Invariants (Priv_T) then
20003 Set_Has_Invariants (Full_T);
20004 Set_Invariant_Procedure (Full_T, Invariant_Procedure (Priv_T));
20007 if Has_Inheritable_Invariants (Priv_T) then
20008 Set_Has_Inheritable_Invariants (Full_T);
20011 -- Check hidden inheritance of class-wide type invariants
20013 if Ada_Version >= Ada_2012
20014 and then not Has_Inheritable_Invariants (Full_T)
20015 and then In_Private_Part (Current_Scope)
20016 and then Has_Interfaces (Full_T)
20023 Collect_Interfaces (Full_T, Ifaces, Exclude_Parents => True);
20025 AI := First_Elmt (Ifaces);
20026 while Present (AI) loop
20027 if Has_Inheritable_Invariants (Node (AI)) then
20029 ("hidden inheritance of class-wide type invariants " &
20039 -- Propagate predicates to full type, and predicate function if already
20040 -- defined. It is not clear that this can actually happen? the partial
20041 -- view cannot be frozen yet, and the predicate function has not been
20042 -- built. Still it is a cheap check and seems safer to make it.
20044 if Has_Predicates (Priv_T) then
20045 if Present (Predicate_Function (Priv_T)) then
20046 Set_Predicate_Function (Full_T, Predicate_Function (Priv_T));
20049 Set_Has_Predicates (Full_T);
20051 end Process_Full_View;
20053 -----------------------------------
20054 -- Process_Incomplete_Dependents --
20055 -----------------------------------
20057 procedure Process_Incomplete_Dependents
20059 Full_T : Entity_Id;
20062 Inc_Elmt : Elmt_Id;
20063 Priv_Dep : Entity_Id;
20064 New_Subt : Entity_Id;
20066 Disc_Constraint : Elist_Id;
20069 if No (Private_Dependents (Inc_T)) then
20073 -- Itypes that may be generated by the completion of an incomplete
20074 -- subtype are not used by the back-end and not attached to the tree.
20075 -- They are created only for constraint-checking purposes.
20077 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
20078 while Present (Inc_Elmt) loop
20079 Priv_Dep := Node (Inc_Elmt);
20081 if Ekind (Priv_Dep) = E_Subprogram_Type then
20083 -- An Access_To_Subprogram type may have a return type or a
20084 -- parameter type that is incomplete. Replace with the full view.
20086 if Etype (Priv_Dep) = Inc_T then
20087 Set_Etype (Priv_Dep, Full_T);
20091 Formal : Entity_Id;
20094 Formal := First_Formal (Priv_Dep);
20095 while Present (Formal) loop
20096 if Etype (Formal) = Inc_T then
20097 Set_Etype (Formal, Full_T);
20100 Next_Formal (Formal);
20104 elsif Is_Overloadable (Priv_Dep) then
20106 -- If a subprogram in the incomplete dependents list is primitive
20107 -- for a tagged full type then mark it as a dispatching operation,
20108 -- check whether it overrides an inherited subprogram, and check
20109 -- restrictions on its controlling formals. Note that a protected
20110 -- operation is never dispatching: only its wrapper operation
20111 -- (which has convention Ada) is.
20113 if Is_Tagged_Type (Full_T)
20114 and then Is_Primitive (Priv_Dep)
20115 and then Convention (Priv_Dep) /= Convention_Protected
20117 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
20118 Set_Is_Dispatching_Operation (Priv_Dep);
20119 Check_Controlling_Formals (Full_T, Priv_Dep);
20122 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
20124 -- Can happen during processing of a body before the completion
20125 -- of a TA type. Ignore, because spec is also on dependent list.
20129 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
20130 -- corresponding subtype of the full view.
20132 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype then
20133 Set_Subtype_Indication
20134 (Parent (Priv_Dep), New_Occurrence_Of (Full_T, Sloc (Priv_Dep)));
20135 Set_Etype (Priv_Dep, Full_T);
20136 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
20137 Set_Analyzed (Parent (Priv_Dep), False);
20139 -- Reanalyze the declaration, suppressing the call to
20140 -- Enter_Name to avoid duplicate names.
20142 Analyze_Subtype_Declaration
20143 (N => Parent (Priv_Dep),
20146 -- Dependent is a subtype
20149 -- We build a new subtype indication using the full view of the
20150 -- incomplete parent. The discriminant constraints have been
20151 -- elaborated already at the point of the subtype declaration.
20153 New_Subt := Create_Itype (E_Void, N);
20155 if Has_Discriminants (Full_T) then
20156 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
20158 Disc_Constraint := No_Elist;
20161 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
20162 Set_Full_View (Priv_Dep, New_Subt);
20165 Next_Elmt (Inc_Elmt);
20167 end Process_Incomplete_Dependents;
20169 --------------------------------
20170 -- Process_Range_Expr_In_Decl --
20171 --------------------------------
20173 procedure Process_Range_Expr_In_Decl
20176 Subtyp : Entity_Id := Empty;
20177 Check_List : List_Id := Empty_List;
20178 R_Check_Off : Boolean := False;
20179 In_Iter_Schm : Boolean := False)
20182 R_Checks : Check_Result;
20183 Insert_Node : Node_Id;
20184 Def_Id : Entity_Id;
20187 Analyze_And_Resolve (R, Base_Type (T));
20189 if Nkind (R) = N_Range then
20191 -- In SPARK, all ranges should be static, with the exception of the
20192 -- discrete type definition of a loop parameter specification.
20194 if not In_Iter_Schm
20195 and then not Is_OK_Static_Range (R)
20197 Check_SPARK_05_Restriction ("range should be static", R);
20200 Lo := Low_Bound (R);
20201 Hi := High_Bound (R);
20203 -- Validity checks on the range of a quantified expression are
20204 -- delayed until the construct is transformed into a loop.
20206 if Nkind (Parent (R)) = N_Loop_Parameter_Specification
20207 and then Nkind (Parent (Parent (R))) = N_Quantified_Expression
20211 -- We need to ensure validity of the bounds here, because if we
20212 -- go ahead and do the expansion, then the expanded code will get
20213 -- analyzed with range checks suppressed and we miss the check.
20215 -- WARNING: The capture of the range bounds with xxx_FIRST/_LAST and
20216 -- the temporaries generated by routine Remove_Side_Effects by means
20217 -- of validity checks must use the same names. When a range appears
20218 -- in the parent of a generic, the range is processed with checks
20219 -- disabled as part of the generic context and with checks enabled
20220 -- for code generation purposes. This leads to link issues as the
20221 -- generic contains references to xxx_FIRST/_LAST, but the inlined
20222 -- template sees the temporaries generated by Remove_Side_Effects.
20225 Validity_Check_Range (R, Subtyp);
20228 -- If there were errors in the declaration, try and patch up some
20229 -- common mistakes in the bounds. The cases handled are literals
20230 -- which are Integer where the expected type is Real and vice versa.
20231 -- These corrections allow the compilation process to proceed further
20232 -- along since some basic assumptions of the format of the bounds
20235 if Etype (R) = Any_Type then
20236 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
20238 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
20240 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
20242 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
20244 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
20246 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
20248 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
20250 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
20257 -- If the bounds of the range have been mistakenly given as string
20258 -- literals (perhaps in place of character literals), then an error
20259 -- has already been reported, but we rewrite the string literal as a
20260 -- bound of the range's type to avoid blowups in later processing
20261 -- that looks at static values.
20263 if Nkind (Lo) = N_String_Literal then
20265 Make_Attribute_Reference (Sloc (Lo),
20266 Prefix => New_Occurrence_Of (T, Sloc (Lo)),
20267 Attribute_Name => Name_First));
20268 Analyze_And_Resolve (Lo);
20271 if Nkind (Hi) = N_String_Literal then
20273 Make_Attribute_Reference (Sloc (Hi),
20274 Prefix => New_Occurrence_Of (T, Sloc (Hi)),
20275 Attribute_Name => Name_First));
20276 Analyze_And_Resolve (Hi);
20279 -- If bounds aren't scalar at this point then exit, avoiding
20280 -- problems with further processing of the range in this procedure.
20282 if not Is_Scalar_Type (Etype (Lo)) then
20286 -- Resolve (actually Sem_Eval) has checked that the bounds are in
20287 -- then range of the base type. Here we check whether the bounds
20288 -- are in the range of the subtype itself. Note that if the bounds
20289 -- represent the null range the Constraint_Error exception should
20292 -- ??? The following code should be cleaned up as follows
20294 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
20295 -- is done in the call to Range_Check (R, T); below
20297 -- 2. The use of R_Check_Off should be investigated and possibly
20298 -- removed, this would clean up things a bit.
20300 if Is_Null_Range (Lo, Hi) then
20304 -- Capture values of bounds and generate temporaries for them
20305 -- if needed, before applying checks, since checks may cause
20306 -- duplication of the expression without forcing evaluation.
20308 -- The forced evaluation removes side effects from expressions,
20309 -- which should occur also in GNATprove mode. Otherwise, we end up
20310 -- with unexpected insertions of actions at places where this is
20311 -- not supposed to occur, e.g. on default parameters of a call.
20313 if Expander_Active or GNATprove_Mode then
20315 -- Call Force_Evaluation to create declarations as needed to
20316 -- deal with side effects, and also create typ_FIRST/LAST
20317 -- entities for bounds if we have a subtype name.
20319 -- Note: we do this transformation even if expansion is not
20320 -- active if we are in GNATprove_Mode since the transformation
20321 -- is in general required to ensure that the resulting tree has
20322 -- proper Ada semantics.
20325 (Lo, Related_Id => Subtyp, Is_Low_Bound => True);
20327 (Hi, Related_Id => Subtyp, Is_High_Bound => True);
20330 -- We use a flag here instead of suppressing checks on the type
20331 -- because the type we check against isn't necessarily the place
20332 -- where we put the check.
20334 if not R_Check_Off then
20335 R_Checks := Get_Range_Checks (R, T);
20337 -- Look up tree to find an appropriate insertion point. We
20338 -- can't just use insert_actions because later processing
20339 -- depends on the insertion node. Prior to Ada 2012 the
20340 -- insertion point could only be a declaration or a loop, but
20341 -- quantified expressions can appear within any context in an
20342 -- expression, and the insertion point can be any statement,
20343 -- pragma, or declaration.
20345 Insert_Node := Parent (R);
20346 while Present (Insert_Node) loop
20348 Nkind (Insert_Node) in N_Declaration
20351 (Insert_Node, N_Component_Declaration,
20352 N_Loop_Parameter_Specification,
20353 N_Function_Specification,
20354 N_Procedure_Specification);
20356 exit when Nkind (Insert_Node) in N_Later_Decl_Item
20357 or else Nkind (Insert_Node) in
20358 N_Statement_Other_Than_Procedure_Call
20359 or else Nkind_In (Insert_Node, N_Procedure_Call_Statement,
20362 Insert_Node := Parent (Insert_Node);
20365 -- Why would Type_Decl not be present??? Without this test,
20366 -- short regression tests fail.
20368 if Present (Insert_Node) then
20370 -- Case of loop statement. Verify that the range is part
20371 -- of the subtype indication of the iteration scheme.
20373 if Nkind (Insert_Node) = N_Loop_Statement then
20378 Indic := Parent (R);
20379 while Present (Indic)
20380 and then Nkind (Indic) /= N_Subtype_Indication
20382 Indic := Parent (Indic);
20385 if Present (Indic) then
20386 Def_Id := Etype (Subtype_Mark (Indic));
20388 Insert_Range_Checks
20392 Sloc (Insert_Node),
20394 Do_Before => True);
20398 -- Insertion before a declaration. If the declaration
20399 -- includes discriminants, the list of applicable checks
20400 -- is given by the caller.
20402 elsif Nkind (Insert_Node) in N_Declaration then
20403 Def_Id := Defining_Identifier (Insert_Node);
20405 if (Ekind (Def_Id) = E_Record_Type
20406 and then Depends_On_Discriminant (R))
20408 (Ekind (Def_Id) = E_Protected_Type
20409 and then Has_Discriminants (Def_Id))
20411 Append_Range_Checks
20413 Check_List, Def_Id, Sloc (Insert_Node), R);
20416 Insert_Range_Checks
20418 Insert_Node, Def_Id, Sloc (Insert_Node), R);
20422 -- Insertion before a statement. Range appears in the
20423 -- context of a quantified expression. Insertion will
20424 -- take place when expression is expanded.
20433 -- Case of other than an explicit N_Range node
20435 -- The forced evaluation removes side effects from expressions, which
20436 -- should occur also in GNATprove mode. Otherwise, we end up with
20437 -- unexpected insertions of actions at places where this is not
20438 -- supposed to occur, e.g. on default parameters of a call.
20440 elsif Expander_Active or GNATprove_Mode then
20441 Get_Index_Bounds (R, Lo, Hi);
20442 Force_Evaluation (Lo);
20443 Force_Evaluation (Hi);
20445 end Process_Range_Expr_In_Decl;
20447 --------------------------------------
20448 -- Process_Real_Range_Specification --
20449 --------------------------------------
20451 procedure Process_Real_Range_Specification (Def : Node_Id) is
20452 Spec : constant Node_Id := Real_Range_Specification (Def);
20455 Err : Boolean := False;
20457 procedure Analyze_Bound (N : Node_Id);
20458 -- Analyze and check one bound
20460 -------------------
20461 -- Analyze_Bound --
20462 -------------------
20464 procedure Analyze_Bound (N : Node_Id) is
20466 Analyze_And_Resolve (N, Any_Real);
20468 if not Is_OK_Static_Expression (N) then
20469 Flag_Non_Static_Expr
20470 ("bound in real type definition is not static!", N);
20475 -- Start of processing for Process_Real_Range_Specification
20478 if Present (Spec) then
20479 Lo := Low_Bound (Spec);
20480 Hi := High_Bound (Spec);
20481 Analyze_Bound (Lo);
20482 Analyze_Bound (Hi);
20484 -- If error, clear away junk range specification
20487 Set_Real_Range_Specification (Def, Empty);
20490 end Process_Real_Range_Specification;
20492 ---------------------
20493 -- Process_Subtype --
20494 ---------------------
20496 function Process_Subtype
20498 Related_Nod : Node_Id;
20499 Related_Id : Entity_Id := Empty;
20500 Suffix : Character := ' ') return Entity_Id
20503 Def_Id : Entity_Id;
20504 Error_Node : Node_Id;
20505 Full_View_Id : Entity_Id;
20506 Subtype_Mark_Id : Entity_Id;
20508 May_Have_Null_Exclusion : Boolean;
20510 procedure Check_Incomplete (T : Entity_Id);
20511 -- Called to verify that an incomplete type is not used prematurely
20513 ----------------------
20514 -- Check_Incomplete --
20515 ----------------------
20517 procedure Check_Incomplete (T : Entity_Id) is
20519 -- Ada 2005 (AI-412): Incomplete subtypes are legal
20521 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
20523 not (Ada_Version >= Ada_2005
20525 (Nkind (Parent (T)) = N_Subtype_Declaration
20526 or else (Nkind (Parent (T)) = N_Subtype_Indication
20527 and then Nkind (Parent (Parent (T))) =
20528 N_Subtype_Declaration)))
20530 Error_Msg_N ("invalid use of type before its full declaration", T);
20532 end Check_Incomplete;
20534 -- Start of processing for Process_Subtype
20537 -- Case of no constraints present
20539 if Nkind (S) /= N_Subtype_Indication then
20541 Check_Incomplete (S);
20544 -- Ada 2005 (AI-231): Static check
20546 if Ada_Version >= Ada_2005
20547 and then Present (P)
20548 and then Null_Exclusion_Present (P)
20549 and then Nkind (P) /= N_Access_To_Object_Definition
20550 and then not Is_Access_Type (Entity (S))
20552 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
20555 -- The following is ugly, can't we have a range or even a flag???
20557 May_Have_Null_Exclusion :=
20558 Nkind_In (P, N_Access_Definition,
20559 N_Access_Function_Definition,
20560 N_Access_Procedure_Definition,
20561 N_Access_To_Object_Definition,
20563 N_Component_Definition)
20565 Nkind_In (P, N_Derived_Type_Definition,
20566 N_Discriminant_Specification,
20567 N_Formal_Object_Declaration,
20568 N_Object_Declaration,
20569 N_Object_Renaming_Declaration,
20570 N_Parameter_Specification,
20571 N_Subtype_Declaration);
20573 -- Create an Itype that is a duplicate of Entity (S) but with the
20574 -- null-exclusion attribute.
20576 if May_Have_Null_Exclusion
20577 and then Is_Access_Type (Entity (S))
20578 and then Null_Exclusion_Present (P)
20580 -- No need to check the case of an access to object definition.
20581 -- It is correct to define double not-null pointers.
20584 -- type Not_Null_Int_Ptr is not null access Integer;
20585 -- type Acc is not null access Not_Null_Int_Ptr;
20587 and then Nkind (P) /= N_Access_To_Object_Definition
20589 if Can_Never_Be_Null (Entity (S)) then
20590 case Nkind (Related_Nod) is
20591 when N_Full_Type_Declaration =>
20592 if Nkind (Type_Definition (Related_Nod))
20593 in N_Array_Type_Definition
20597 (Component_Definition
20598 (Type_Definition (Related_Nod)));
20601 Subtype_Indication (Type_Definition (Related_Nod));
20604 when N_Subtype_Declaration =>
20605 Error_Node := Subtype_Indication (Related_Nod);
20607 when N_Object_Declaration =>
20608 Error_Node := Object_Definition (Related_Nod);
20610 when N_Component_Declaration =>
20612 Subtype_Indication (Component_Definition (Related_Nod));
20614 when N_Allocator =>
20615 Error_Node := Expression (Related_Nod);
20618 pragma Assert (False);
20619 Error_Node := Related_Nod;
20623 ("`NOT NULL` not allowed (& already excludes null)",
20629 Create_Null_Excluding_Itype
20631 Related_Nod => P));
20632 Set_Entity (S, Etype (S));
20637 -- Case of constraint present, so that we have an N_Subtype_Indication
20638 -- node (this node is created only if constraints are present).
20641 Find_Type (Subtype_Mark (S));
20643 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
20645 (Nkind (Parent (S)) = N_Subtype_Declaration
20646 and then Is_Itype (Defining_Identifier (Parent (S))))
20648 Check_Incomplete (Subtype_Mark (S));
20652 Subtype_Mark_Id := Entity (Subtype_Mark (S));
20654 -- Explicit subtype declaration case
20656 if Nkind (P) = N_Subtype_Declaration then
20657 Def_Id := Defining_Identifier (P);
20659 -- Explicit derived type definition case
20661 elsif Nkind (P) = N_Derived_Type_Definition then
20662 Def_Id := Defining_Identifier (Parent (P));
20664 -- Implicit case, the Def_Id must be created as an implicit type.
20665 -- The one exception arises in the case of concurrent types, array
20666 -- and access types, where other subsidiary implicit types may be
20667 -- created and must appear before the main implicit type. In these
20668 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
20669 -- has not yet been called to create Def_Id.
20672 if Is_Array_Type (Subtype_Mark_Id)
20673 or else Is_Concurrent_Type (Subtype_Mark_Id)
20674 or else Is_Access_Type (Subtype_Mark_Id)
20678 -- For the other cases, we create a new unattached Itype,
20679 -- and set the indication to ensure it gets attached later.
20683 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
20687 -- If the kind of constraint is invalid for this kind of type,
20688 -- then give an error, and then pretend no constraint was given.
20690 if not Is_Valid_Constraint_Kind
20691 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
20694 ("incorrect constraint for this kind of type", Constraint (S));
20696 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
20698 -- Set Ekind of orphan itype, to prevent cascaded errors
20700 if Present (Def_Id) then
20701 Set_Ekind (Def_Id, Ekind (Any_Type));
20704 -- Make recursive call, having got rid of the bogus constraint
20706 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
20709 -- Remaining processing depends on type. Select on Base_Type kind to
20710 -- ensure getting to the concrete type kind in the case of a private
20711 -- subtype (needed when only doing semantic analysis).
20713 case Ekind (Base_Type (Subtype_Mark_Id)) is
20714 when Access_Kind =>
20716 -- If this is a constraint on a class-wide type, discard it.
20717 -- There is currently no way to express a partial discriminant
20718 -- constraint on a type with unknown discriminants. This is
20719 -- a pathology that the ACATS wisely decides not to test.
20721 if Is_Class_Wide_Type (Designated_Type (Subtype_Mark_Id)) then
20722 if Comes_From_Source (S) then
20724 ("constraint on class-wide type ignored??",
20728 if Nkind (P) = N_Subtype_Declaration then
20729 Set_Subtype_Indication (P,
20730 New_Occurrence_Of (Subtype_Mark_Id, Sloc (S)));
20733 return Subtype_Mark_Id;
20736 Constrain_Access (Def_Id, S, Related_Nod);
20739 and then Is_Itype (Designated_Type (Def_Id))
20740 and then Nkind (Related_Nod) = N_Subtype_Declaration
20741 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
20743 Build_Itype_Reference
20744 (Designated_Type (Def_Id), Related_Nod);
20748 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
20750 when Decimal_Fixed_Point_Kind =>
20751 Constrain_Decimal (Def_Id, S);
20753 when Enumeration_Kind =>
20754 Constrain_Enumeration (Def_Id, S);
20755 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
20757 when Ordinary_Fixed_Point_Kind =>
20758 Constrain_Ordinary_Fixed (Def_Id, S);
20761 Constrain_Float (Def_Id, S);
20763 when Integer_Kind =>
20764 Constrain_Integer (Def_Id, S);
20765 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
20767 when E_Record_Type |
20770 E_Incomplete_Type =>
20771 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
20773 if Ekind (Def_Id) = E_Incomplete_Type then
20774 Set_Private_Dependents (Def_Id, New_Elmt_List);
20777 when Private_Kind =>
20778 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
20780 -- The base type may be private but Def_Id may be a full view
20783 if Is_Private_Type (Def_Id) then
20784 Set_Private_Dependents (Def_Id, New_Elmt_List);
20787 -- In case of an invalid constraint prevent further processing
20788 -- since the type constructed is missing expected fields.
20790 if Etype (Def_Id) = Any_Type then
20794 -- If the full view is that of a task with discriminants,
20795 -- we must constrain both the concurrent type and its
20796 -- corresponding record type. Otherwise we will just propagate
20797 -- the constraint to the full view, if available.
20799 if Present (Full_View (Subtype_Mark_Id))
20800 and then Has_Discriminants (Subtype_Mark_Id)
20801 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
20804 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
20806 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
20807 Constrain_Concurrent (Full_View_Id, S,
20808 Related_Nod, Related_Id, Suffix);
20809 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
20810 Set_Full_View (Def_Id, Full_View_Id);
20812 -- Introduce an explicit reference to the private subtype,
20813 -- to prevent scope anomalies in gigi if first use appears
20814 -- in a nested context, e.g. a later function body.
20815 -- Should this be generated in other contexts than a full
20816 -- type declaration?
20818 if Is_Itype (Def_Id)
20820 Nkind (Parent (P)) = N_Full_Type_Declaration
20822 Build_Itype_Reference (Def_Id, Parent (P));
20826 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
20829 when Concurrent_Kind =>
20830 Constrain_Concurrent (Def_Id, S,
20831 Related_Nod, Related_Id, Suffix);
20834 Error_Msg_N ("invalid subtype mark in subtype indication", S);
20837 -- Size and Convention are always inherited from the base type
20839 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
20840 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
20844 end Process_Subtype;
20846 --------------------------------------------
20847 -- Propagate_Default_Init_Cond_Attributes --
20848 --------------------------------------------
20850 procedure Propagate_Default_Init_Cond_Attributes
20851 (From_Typ : Entity_Id;
20852 To_Typ : Entity_Id;
20853 Parent_To_Derivation : Boolean := False;
20854 Private_To_Full_View : Boolean := False)
20856 procedure Remove_Default_Init_Cond_Procedure (Typ : Entity_Id);
20857 -- Remove the default initial procedure (if any) from the rep chain of
20860 ----------------------------------------
20861 -- Remove_Default_Init_Cond_Procedure --
20862 ----------------------------------------
20864 procedure Remove_Default_Init_Cond_Procedure (Typ : Entity_Id) is
20865 Found : Boolean := False;
20871 Subp := Subprograms_For_Type (Typ);
20872 while Present (Subp) loop
20873 if Is_Default_Init_Cond_Procedure (Subp) then
20879 Subp := Subprograms_For_Type (Subp);
20883 Set_Subprograms_For_Type (Prev, Subprograms_For_Type (Subp));
20884 Set_Subprograms_For_Type (Subp, Empty);
20886 end Remove_Default_Init_Cond_Procedure;
20890 Inherit_Procedure : Boolean := False;
20892 -- Start of processing for Propagate_Default_Init_Cond_Attributes
20895 if Has_Default_Init_Cond (From_Typ) then
20897 -- A derived type inherits the attributes from its parent type
20899 if Parent_To_Derivation then
20900 Set_Has_Inherited_Default_Init_Cond (To_Typ);
20902 -- A full view shares the attributes with its private view
20905 Set_Has_Default_Init_Cond (To_Typ);
20908 Inherit_Procedure := True;
20910 -- Due to the order of expansion, a derived private type is processed
20911 -- by two routines which both attempt to set the attributes related
20912 -- to pragma Default_Initial_Condition - Build_Derived_Type and then
20913 -- Process_Full_View.
20916 -- type Parent_Typ is private
20917 -- with Default_Initial_Condition ...;
20919 -- type Parent_Typ is ...;
20922 -- with Pack; use Pack;
20923 -- package Pack_2 is
20924 -- type Deriv_Typ is private
20925 -- with Default_Initial_Condition ...;
20927 -- type Deriv_Typ is new Parent_Typ;
20930 -- When Build_Derived_Type operates, it sets the attributes on the
20931 -- full view without taking into account that the private view may
20932 -- define its own default initial condition procedure. This becomes
20933 -- apparent in Process_Full_View which must undo some of the work by
20934 -- Build_Derived_Type and propagate the attributes from the private
20935 -- to the full view.
20937 if Private_To_Full_View then
20938 Set_Has_Inherited_Default_Init_Cond (To_Typ, False);
20939 Remove_Default_Init_Cond_Procedure (To_Typ);
20942 -- A type must inherit the default initial condition procedure from a
20943 -- parent type when the parent itself is inheriting the procedure or
20944 -- when it is defining one. This circuitry is also used when dealing
20945 -- with the private / full view of a type.
20947 elsif Has_Inherited_Default_Init_Cond (From_Typ)
20948 or (Parent_To_Derivation
20949 and Present (Get_Pragma
20950 (From_Typ, Pragma_Default_Initial_Condition)))
20952 Set_Has_Inherited_Default_Init_Cond (To_Typ);
20953 Inherit_Procedure := True;
20956 if Inherit_Procedure
20957 and then No (Default_Init_Cond_Procedure (To_Typ))
20959 Set_Default_Init_Cond_Procedure
20960 (To_Typ, Default_Init_Cond_Procedure (From_Typ));
20962 end Propagate_Default_Init_Cond_Attributes;
20964 -----------------------------
20965 -- Record_Type_Declaration --
20966 -----------------------------
20968 procedure Record_Type_Declaration
20973 Def : constant Node_Id := Type_Definition (N);
20974 Is_Tagged : Boolean;
20975 Tag_Comp : Entity_Id;
20978 -- These flags must be initialized before calling Process_Discriminants
20979 -- because this routine makes use of them.
20981 Set_Ekind (T, E_Record_Type);
20983 Init_Size_Align (T);
20984 Set_Interfaces (T, No_Elist);
20985 Set_Stored_Constraint (T, No_Elist);
20986 Set_Default_SSO (T);
20990 if Ada_Version < Ada_2005 or else not Interface_Present (Def) then
20991 if Limited_Present (Def) then
20992 Check_SPARK_05_Restriction ("limited is not allowed", N);
20995 if Abstract_Present (Def) then
20996 Check_SPARK_05_Restriction ("abstract is not allowed", N);
20999 -- The flag Is_Tagged_Type might have already been set by
21000 -- Find_Type_Name if it detected an error for declaration T. This
21001 -- arises in the case of private tagged types where the full view
21002 -- omits the word tagged.
21005 Tagged_Present (Def)
21006 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
21008 Set_Is_Limited_Record (T, Limited_Present (Def));
21011 Set_Is_Tagged_Type (T, True);
21012 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
21015 -- Type is abstract if full declaration carries keyword, or if
21016 -- previous partial view did.
21018 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
21019 or else Abstract_Present (Def));
21022 Check_SPARK_05_Restriction ("interface is not allowed", N);
21025 Analyze_Interface_Declaration (T, Def);
21027 if Present (Discriminant_Specifications (N)) then
21029 ("interface types cannot have discriminants",
21030 Defining_Identifier
21031 (First (Discriminant_Specifications (N))));
21035 -- First pass: if there are self-referential access components,
21036 -- create the required anonymous access type declarations, and if
21037 -- need be an incomplete type declaration for T itself.
21039 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
21041 if Ada_Version >= Ada_2005
21042 and then Present (Interface_List (Def))
21044 Check_Interfaces (N, Def);
21047 Ifaces_List : Elist_Id;
21050 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
21051 -- already in the parents.
21055 Ifaces_List => Ifaces_List,
21056 Exclude_Parents => True);
21058 Set_Interfaces (T, Ifaces_List);
21062 -- Records constitute a scope for the component declarations within.
21063 -- The scope is created prior to the processing of these declarations.
21064 -- Discriminants are processed first, so that they are visible when
21065 -- processing the other components. The Ekind of the record type itself
21066 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
21068 -- Enter record scope
21072 -- If an incomplete or private type declaration was already given for
21073 -- the type, then this scope already exists, and the discriminants have
21074 -- been declared within. We must verify that the full declaration
21075 -- matches the incomplete one.
21077 Check_Or_Process_Discriminants (N, T, Prev);
21079 Set_Is_Constrained (T, not Has_Discriminants (T));
21080 Set_Has_Delayed_Freeze (T, True);
21082 -- For tagged types add a manually analyzed component corresponding
21083 -- to the component _tag, the corresponding piece of tree will be
21084 -- expanded as part of the freezing actions if it is not a CPP_Class.
21088 -- Do not add the tag unless we are in expansion mode
21090 if Expander_Active then
21091 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
21092 Enter_Name (Tag_Comp);
21094 Set_Ekind (Tag_Comp, E_Component);
21095 Set_Is_Tag (Tag_Comp);
21096 Set_Is_Aliased (Tag_Comp);
21097 Set_Etype (Tag_Comp, RTE (RE_Tag));
21098 Set_DT_Entry_Count (Tag_Comp, No_Uint);
21099 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
21100 Init_Component_Location (Tag_Comp);
21102 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
21103 -- implemented interfaces.
21105 if Has_Interfaces (T) then
21106 Add_Interface_Tag_Components (N, T);
21110 Make_Class_Wide_Type (T);
21111 Set_Direct_Primitive_Operations (T, New_Elmt_List);
21114 -- We must suppress range checks when processing record components in
21115 -- the presence of discriminants, since we don't want spurious checks to
21116 -- be generated during their analysis, but Suppress_Range_Checks flags
21117 -- must be reset the after processing the record definition.
21119 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
21120 -- couldn't we just use the normal range check suppression method here.
21121 -- That would seem cleaner ???
21123 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
21124 Set_Kill_Range_Checks (T, True);
21125 Record_Type_Definition (Def, Prev);
21126 Set_Kill_Range_Checks (T, False);
21128 Record_Type_Definition (Def, Prev);
21131 -- Exit from record scope
21135 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
21136 -- the implemented interfaces and associate them an aliased entity.
21139 and then not Is_Empty_List (Interface_List (Def))
21141 Derive_Progenitor_Subprograms (T, T);
21144 Check_Function_Writable_Actuals (N);
21145 end Record_Type_Declaration;
21147 ----------------------------
21148 -- Record_Type_Definition --
21149 ----------------------------
21151 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
21152 Component : Entity_Id;
21153 Ctrl_Components : Boolean := False;
21154 Final_Storage_Only : Boolean;
21158 if Ekind (Prev_T) = E_Incomplete_Type then
21159 T := Full_View (Prev_T);
21164 -- In SPARK, tagged types and type extensions may only be declared in
21165 -- the specification of library unit packages.
21167 if Present (Def) and then Is_Tagged_Type (T) then
21173 if Nkind (Parent (Def)) = N_Full_Type_Declaration then
21174 Typ := Parent (Def);
21177 (Nkind (Parent (Def)) = N_Derived_Type_Definition);
21178 Typ := Parent (Parent (Def));
21181 Ctxt := Parent (Typ);
21183 if Nkind (Ctxt) = N_Package_Body
21184 and then Nkind (Parent (Ctxt)) = N_Compilation_Unit
21186 Check_SPARK_05_Restriction
21187 ("type should be defined in package specification", Typ);
21189 elsif Nkind (Ctxt) /= N_Package_Specification
21190 or else Nkind (Parent (Parent (Ctxt))) /= N_Compilation_Unit
21192 Check_SPARK_05_Restriction
21193 ("type should be defined in library unit package", Typ);
21198 Final_Storage_Only := not Is_Controlled_Active (T);
21200 -- Ada 2005: Check whether an explicit Limited is present in a derived
21201 -- type declaration.
21203 if Nkind (Parent (Def)) = N_Derived_Type_Definition
21204 and then Limited_Present (Parent (Def))
21206 Set_Is_Limited_Record (T);
21209 -- If the component list of a record type is defined by the reserved
21210 -- word null and there is no discriminant part, then the record type has
21211 -- no components and all records of the type are null records (RM 3.7)
21212 -- This procedure is also called to process the extension part of a
21213 -- record extension, in which case the current scope may have inherited
21217 or else No (Component_List (Def))
21218 or else Null_Present (Component_List (Def))
21220 if not Is_Tagged_Type (T) then
21221 Check_SPARK_05_Restriction ("untagged record cannot be null", Def);
21225 Analyze_Declarations (Component_Items (Component_List (Def)));
21227 if Present (Variant_Part (Component_List (Def))) then
21228 Check_SPARK_05_Restriction ("variant part is not allowed", Def);
21229 Analyze (Variant_Part (Component_List (Def)));
21233 -- After completing the semantic analysis of the record definition,
21234 -- record components, both new and inherited, are accessible. Set their
21235 -- kind accordingly. Exclude malformed itypes from illegal declarations,
21236 -- whose Ekind may be void.
21238 Component := First_Entity (Current_Scope);
21239 while Present (Component) loop
21240 if Ekind (Component) = E_Void
21241 and then not Is_Itype (Component)
21243 Set_Ekind (Component, E_Component);
21244 Init_Component_Location (Component);
21247 if Has_Task (Etype (Component)) then
21251 if Has_Protected (Etype (Component)) then
21252 Set_Has_Protected (T);
21255 if Ekind (Component) /= E_Component then
21258 -- Do not set Has_Controlled_Component on a class-wide equivalent
21259 -- type. See Make_CW_Equivalent_Type.
21261 elsif not Is_Class_Wide_Equivalent_Type (T)
21262 and then (Has_Controlled_Component (Etype (Component))
21263 or else (Chars (Component) /= Name_uParent
21264 and then Is_Controlled_Active
21265 (Etype (Component))))
21267 Set_Has_Controlled_Component (T, True);
21268 Final_Storage_Only :=
21270 and then Finalize_Storage_Only (Etype (Component));
21271 Ctrl_Components := True;
21274 Next_Entity (Component);
21277 -- A Type is Finalize_Storage_Only only if all its controlled components
21280 if Ctrl_Components then
21281 Set_Finalize_Storage_Only (T, Final_Storage_Only);
21284 -- Place reference to end record on the proper entity, which may
21285 -- be a partial view.
21287 if Present (Def) then
21288 Process_End_Label (Def, 'e', Prev_T);
21290 end Record_Type_Definition;
21292 ------------------------
21293 -- Replace_Components --
21294 ------------------------
21296 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
21297 function Process (N : Node_Id) return Traverse_Result;
21303 function Process (N : Node_Id) return Traverse_Result is
21307 if Nkind (N) = N_Discriminant_Specification then
21308 Comp := First_Discriminant (Typ);
21309 while Present (Comp) loop
21310 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21311 Set_Defining_Identifier (N, Comp);
21315 Next_Discriminant (Comp);
21318 elsif Nkind (N) = N_Component_Declaration then
21319 Comp := First_Component (Typ);
21320 while Present (Comp) loop
21321 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21322 Set_Defining_Identifier (N, Comp);
21326 Next_Component (Comp);
21333 procedure Replace is new Traverse_Proc (Process);
21335 -- Start of processing for Replace_Components
21339 end Replace_Components;
21341 -------------------------------
21342 -- Set_Completion_Referenced --
21343 -------------------------------
21345 procedure Set_Completion_Referenced (E : Entity_Id) is
21347 -- If in main unit, mark entity that is a completion as referenced,
21348 -- warnings go on the partial view when needed.
21350 if In_Extended_Main_Source_Unit (E) then
21351 Set_Referenced (E);
21353 end Set_Completion_Referenced;
21355 ---------------------
21356 -- Set_Default_SSO --
21357 ---------------------
21359 procedure Set_Default_SSO (T : Entity_Id) is
21361 case Opt.Default_SSO is
21365 Set_SSO_Set_Low_By_Default (T, True);
21367 Set_SSO_Set_High_By_Default (T, True);
21369 raise Program_Error;
21371 end Set_Default_SSO;
21373 ---------------------
21374 -- Set_Fixed_Range --
21375 ---------------------
21377 -- The range for fixed-point types is complicated by the fact that we
21378 -- do not know the exact end points at the time of the declaration. This
21379 -- is true for three reasons:
21381 -- A size clause may affect the fudging of the end-points.
21382 -- A small clause may affect the values of the end-points.
21383 -- We try to include the end-points if it does not affect the size.
21385 -- This means that the actual end-points must be established at the
21386 -- point when the type is frozen. Meanwhile, we first narrow the range
21387 -- as permitted (so that it will fit if necessary in a small specified
21388 -- size), and then build a range subtree with these narrowed bounds.
21389 -- Set_Fixed_Range constructs the range from real literal values, and
21390 -- sets the range as the Scalar_Range of the given fixed-point type entity.
21392 -- The parent of this range is set to point to the entity so that it is
21393 -- properly hooked into the tree (unlike normal Scalar_Range entries for
21394 -- other scalar types, which are just pointers to the range in the
21395 -- original tree, this would otherwise be an orphan).
21397 -- The tree is left unanalyzed. When the type is frozen, the processing
21398 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
21399 -- analyzed, and uses this as an indication that it should complete
21400 -- work on the range (it will know the final small and size values).
21402 procedure Set_Fixed_Range
21408 S : constant Node_Id :=
21410 Low_Bound => Make_Real_Literal (Loc, Lo),
21411 High_Bound => Make_Real_Literal (Loc, Hi));
21413 Set_Scalar_Range (E, S);
21416 -- Before the freeze point, the bounds of a fixed point are universal
21417 -- and carry the corresponding type.
21419 Set_Etype (Low_Bound (S), Universal_Real);
21420 Set_Etype (High_Bound (S), Universal_Real);
21421 end Set_Fixed_Range;
21423 ----------------------------------
21424 -- Set_Scalar_Range_For_Subtype --
21425 ----------------------------------
21427 procedure Set_Scalar_Range_For_Subtype
21428 (Def_Id : Entity_Id;
21432 Kind : constant Entity_Kind := Ekind (Def_Id);
21435 -- Defend against previous error
21437 if Nkind (R) = N_Error then
21441 Set_Scalar_Range (Def_Id, R);
21443 -- We need to link the range into the tree before resolving it so
21444 -- that types that are referenced, including importantly the subtype
21445 -- itself, are properly frozen (Freeze_Expression requires that the
21446 -- expression be properly linked into the tree). Of course if it is
21447 -- already linked in, then we do not disturb the current link.
21449 if No (Parent (R)) then
21450 Set_Parent (R, Def_Id);
21453 -- Reset the kind of the subtype during analysis of the range, to
21454 -- catch possible premature use in the bounds themselves.
21456 Set_Ekind (Def_Id, E_Void);
21457 Process_Range_Expr_In_Decl (R, Subt, Subtyp => Def_Id);
21458 Set_Ekind (Def_Id, Kind);
21459 end Set_Scalar_Range_For_Subtype;
21461 --------------------------------------------------------
21462 -- Set_Stored_Constraint_From_Discriminant_Constraint --
21463 --------------------------------------------------------
21465 procedure Set_Stored_Constraint_From_Discriminant_Constraint
21469 -- Make sure set if encountered during Expand_To_Stored_Constraint
21471 Set_Stored_Constraint (E, No_Elist);
21473 -- Give it the right value
21475 if Is_Constrained (E) and then Has_Discriminants (E) then
21476 Set_Stored_Constraint (E,
21477 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
21479 end Set_Stored_Constraint_From_Discriminant_Constraint;
21481 -------------------------------------
21482 -- Signed_Integer_Type_Declaration --
21483 -------------------------------------
21485 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
21486 Implicit_Base : Entity_Id;
21487 Base_Typ : Entity_Id;
21490 Errs : Boolean := False;
21494 function Can_Derive_From (E : Entity_Id) return Boolean;
21495 -- Determine whether given bounds allow derivation from specified type
21497 procedure Check_Bound (Expr : Node_Id);
21498 -- Check bound to make sure it is integral and static. If not, post
21499 -- appropriate error message and set Errs flag
21501 ---------------------
21502 -- Can_Derive_From --
21503 ---------------------
21505 -- Note we check both bounds against both end values, to deal with
21506 -- strange types like ones with a range of 0 .. -12341234.
21508 function Can_Derive_From (E : Entity_Id) return Boolean is
21509 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
21510 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
21512 return Lo <= Lo_Val and then Lo_Val <= Hi
21514 Lo <= Hi_Val and then Hi_Val <= Hi;
21515 end Can_Derive_From;
21521 procedure Check_Bound (Expr : Node_Id) is
21523 -- If a range constraint is used as an integer type definition, each
21524 -- bound of the range must be defined by a static expression of some
21525 -- integer type, but the two bounds need not have the same integer
21526 -- type (Negative bounds are allowed.) (RM 3.5.4)
21528 if not Is_Integer_Type (Etype (Expr)) then
21530 ("integer type definition bounds must be of integer type", Expr);
21533 elsif not Is_OK_Static_Expression (Expr) then
21534 Flag_Non_Static_Expr
21535 ("non-static expression used for integer type bound!", Expr);
21538 -- The bounds are folded into literals, and we set their type to be
21539 -- universal, to avoid typing difficulties: we cannot set the type
21540 -- of the literal to the new type, because this would be a forward
21541 -- reference for the back end, and if the original type is user-
21542 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
21545 if Is_Entity_Name (Expr) then
21546 Fold_Uint (Expr, Expr_Value (Expr), True);
21549 Set_Etype (Expr, Universal_Integer);
21553 -- Start of processing for Signed_Integer_Type_Declaration
21556 -- Create an anonymous base type
21559 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
21561 -- Analyze and check the bounds, they can be of any integer type
21563 Lo := Low_Bound (Def);
21564 Hi := High_Bound (Def);
21566 -- Arbitrarily use Integer as the type if either bound had an error
21568 if Hi = Error or else Lo = Error then
21569 Base_Typ := Any_Integer;
21570 Set_Error_Posted (T, True);
21572 -- Here both bounds are OK expressions
21575 Analyze_And_Resolve (Lo, Any_Integer);
21576 Analyze_And_Resolve (Hi, Any_Integer);
21582 Hi := Type_High_Bound (Standard_Long_Long_Integer);
21583 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
21586 -- Find type to derive from
21588 Lo_Val := Expr_Value (Lo);
21589 Hi_Val := Expr_Value (Hi);
21591 if Can_Derive_From (Standard_Short_Short_Integer) then
21592 Base_Typ := Base_Type (Standard_Short_Short_Integer);
21594 elsif Can_Derive_From (Standard_Short_Integer) then
21595 Base_Typ := Base_Type (Standard_Short_Integer);
21597 elsif Can_Derive_From (Standard_Integer) then
21598 Base_Typ := Base_Type (Standard_Integer);
21600 elsif Can_Derive_From (Standard_Long_Integer) then
21601 Base_Typ := Base_Type (Standard_Long_Integer);
21603 elsif Can_Derive_From (Standard_Long_Long_Integer) then
21604 Check_Restriction (No_Long_Long_Integers, Def);
21605 Base_Typ := Base_Type (Standard_Long_Long_Integer);
21608 Base_Typ := Base_Type (Standard_Long_Long_Integer);
21609 Error_Msg_N ("integer type definition bounds out of range", Def);
21610 Hi := Type_High_Bound (Standard_Long_Long_Integer);
21611 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
21615 -- Complete both implicit base and declared first subtype entities. The
21616 -- inheritance of the rep item chain ensures that SPARK-related pragmas
21617 -- are not clobbered when the signed integer type acts as a full view of
21620 Set_Etype (Implicit_Base, Base_Typ);
21621 Set_Size_Info (Implicit_Base, Base_Typ);
21622 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
21623 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
21624 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
21626 Set_Ekind (T, E_Signed_Integer_Subtype);
21627 Set_Etype (T, Implicit_Base);
21628 Set_Size_Info (T, Implicit_Base);
21629 Inherit_Rep_Item_Chain (T, Implicit_Base);
21630 Set_Scalar_Range (T, Def);
21631 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
21632 Set_Is_Constrained (T);
21633 end Signed_Integer_Type_Declaration;