1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2015, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Aspects; use Aspects;
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Debug; use Debug;
30 with Elists; use Elists;
31 with Einfo; use Einfo;
32 with Errout; use Errout;
33 with Eval_Fat; use Eval_Fat;
34 with Exp_Ch3; use Exp_Ch3;
35 with Exp_Ch9; use Exp_Ch9;
36 with Exp_Disp; use Exp_Disp;
37 with Exp_Dist; use Exp_Dist;
38 with Exp_Tss; use Exp_Tss;
39 with Exp_Util; use Exp_Util;
40 with Fname; use Fname;
41 with Freeze; use Freeze;
42 with Ghost; use Ghost;
43 with Itypes; use Itypes;
44 with Layout; use Layout;
46 with Lib.Xref; use Lib.Xref;
47 with Namet; use Namet;
48 with Nmake; use Nmake;
50 with Restrict; use Restrict;
51 with Rident; use Rident;
52 with Rtsfind; use Rtsfind;
54 with Sem_Aux; use Sem_Aux;
55 with Sem_Case; use Sem_Case;
56 with Sem_Cat; use Sem_Cat;
57 with Sem_Ch6; use Sem_Ch6;
58 with Sem_Ch7; use Sem_Ch7;
59 with Sem_Ch8; use Sem_Ch8;
60 with Sem_Ch10; use Sem_Ch10;
61 with Sem_Ch12; use Sem_Ch12;
62 with Sem_Ch13; use Sem_Ch13;
63 with Sem_Dim; use Sem_Dim;
64 with Sem_Disp; use Sem_Disp;
65 with Sem_Dist; use Sem_Dist;
66 with Sem_Elim; use Sem_Elim;
67 with Sem_Eval; use Sem_Eval;
68 with Sem_Mech; use Sem_Mech;
69 with Sem_Prag; use Sem_Prag;
70 with Sem_Res; use Sem_Res;
71 with Sem_Smem; use Sem_Smem;
72 with Sem_Type; use Sem_Type;
73 with Sem_Util; use Sem_Util;
74 with Sem_Warn; use Sem_Warn;
75 with Stand; use Stand;
76 with Sinfo; use Sinfo;
77 with Sinput; use Sinput;
78 with Snames; use Snames;
79 with Targparm; use Targparm;
80 with Tbuild; use Tbuild;
81 with Ttypes; use Ttypes;
82 with Uintp; use Uintp;
83 with Urealp; use Urealp;
85 package body Sem_Ch3 is
87 -----------------------
88 -- Local Subprograms --
89 -----------------------
91 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id);
92 -- Ada 2005 (AI-251): Add the tag components corresponding to all the
93 -- abstract interface types implemented by a record type or a derived
96 procedure Analyze_Object_Contract (Obj_Id : Entity_Id);
97 -- Analyze all delayed pragmas chained on the contract of object Obj_Id as
98 -- if they appeared at the end of the declarative region. The pragmas to be
106 procedure Build_Derived_Type
108 Parent_Type : Entity_Id;
109 Derived_Type : Entity_Id;
110 Is_Completion : Boolean;
111 Derive_Subps : Boolean := True);
112 -- Create and decorate a Derived_Type given the Parent_Type entity. N is
113 -- the N_Full_Type_Declaration node containing the derived type definition.
114 -- Parent_Type is the entity for the parent type in the derived type
115 -- definition and Derived_Type the actual derived type. Is_Completion must
116 -- be set to False if Derived_Type is the N_Defining_Identifier node in N
117 -- (i.e. Derived_Type = Defining_Identifier (N)). In this case N is not the
118 -- completion of a private type declaration. If Is_Completion is set to
119 -- True, N is the completion of a private type declaration and Derived_Type
120 -- is different from the defining identifier inside N (i.e. Derived_Type /=
121 -- Defining_Identifier (N)). Derive_Subps indicates whether the parent
122 -- subprograms should be derived. The only case where this parameter is
123 -- False is when Build_Derived_Type is recursively called to process an
124 -- implicit derived full type for a type derived from a private type (in
125 -- that case the subprograms must only be derived for the private view of
128 -- ??? These flags need a bit of re-examination and re-documentation:
129 -- ??? are they both necessary (both seem related to the recursion)?
131 procedure Build_Derived_Access_Type
133 Parent_Type : Entity_Id;
134 Derived_Type : Entity_Id);
135 -- Subsidiary procedure to Build_Derived_Type. For a derived access type,
136 -- create an implicit base if the parent type is constrained or if the
137 -- subtype indication has a constraint.
139 procedure Build_Derived_Array_Type
141 Parent_Type : Entity_Id;
142 Derived_Type : Entity_Id);
143 -- Subsidiary procedure to Build_Derived_Type. For a derived array type,
144 -- create an implicit base if the parent type is constrained or if the
145 -- subtype indication has a constraint.
147 procedure Build_Derived_Concurrent_Type
149 Parent_Type : Entity_Id;
150 Derived_Type : Entity_Id);
151 -- Subsidiary procedure to Build_Derived_Type. For a derived task or
152 -- protected type, inherit entries and protected subprograms, check
153 -- legality of discriminant constraints if any.
155 procedure Build_Derived_Enumeration_Type
157 Parent_Type : Entity_Id;
158 Derived_Type : Entity_Id);
159 -- Subsidiary procedure to Build_Derived_Type. For a derived enumeration
160 -- type, we must create a new list of literals. Types derived from
161 -- Character and [Wide_]Wide_Character are special-cased.
163 procedure Build_Derived_Numeric_Type
165 Parent_Type : Entity_Id;
166 Derived_Type : Entity_Id);
167 -- Subsidiary procedure to Build_Derived_Type. For numeric types, create
168 -- an anonymous base type, and propagate constraint to subtype if needed.
170 procedure Build_Derived_Private_Type
172 Parent_Type : Entity_Id;
173 Derived_Type : Entity_Id;
174 Is_Completion : Boolean;
175 Derive_Subps : Boolean := True);
176 -- Subsidiary procedure to Build_Derived_Type. This procedure is complex
177 -- because the parent may or may not have a completion, and the derivation
178 -- may itself be a completion.
180 procedure Build_Derived_Record_Type
182 Parent_Type : Entity_Id;
183 Derived_Type : Entity_Id;
184 Derive_Subps : Boolean := True);
185 -- Subsidiary procedure used for tagged and untagged record types
186 -- by Build_Derived_Type and Analyze_Private_Extension_Declaration.
187 -- All parameters are as in Build_Derived_Type except that N, in
188 -- addition to being an N_Full_Type_Declaration node, can also be an
189 -- N_Private_Extension_Declaration node. See the definition of this routine
190 -- for much more info. Derive_Subps indicates whether subprograms should be
191 -- derived from the parent type. The only case where Derive_Subps is False
192 -- is for an implicit derived full type for a type derived from a private
193 -- type (see Build_Derived_Type).
195 procedure Build_Discriminal (Discrim : Entity_Id);
196 -- Create the discriminal corresponding to discriminant Discrim, that is
197 -- the parameter corresponding to Discrim to be used in initialization
198 -- procedures for the type where Discrim is a discriminant. Discriminals
199 -- are not used during semantic analysis, and are not fully defined
200 -- entities until expansion. Thus they are not given a scope until
201 -- initialization procedures are built.
203 function Build_Discriminant_Constraints
206 Derived_Def : Boolean := False) return Elist_Id;
207 -- Validate discriminant constraints and return the list of the constraints
208 -- in order of discriminant declarations, where T is the discriminated
209 -- unconstrained type. Def is the N_Subtype_Indication node where the
210 -- discriminants constraints for T are specified. Derived_Def is True
211 -- when building the discriminant constraints in a derived type definition
212 -- of the form "type D (...) is new T (xxx)". In this case T is the parent
213 -- type and Def is the constraint "(xxx)" on T and this routine sets the
214 -- Corresponding_Discriminant field of the discriminants in the derived
215 -- type D to point to the corresponding discriminants in the parent type T.
217 procedure Build_Discriminated_Subtype
221 Related_Nod : Node_Id;
222 For_Access : Boolean := False);
223 -- Subsidiary procedure to Constrain_Discriminated_Type and to
224 -- Process_Incomplete_Dependents. Given
226 -- T (a possibly discriminated base type)
227 -- Def_Id (a very partially built subtype for T),
229 -- the call completes Def_Id to be the appropriate E_*_Subtype.
231 -- The Elist is the list of discriminant constraints if any (it is set
232 -- to No_Elist if T is not a discriminated type, and to an empty list if
233 -- T has discriminants but there are no discriminant constraints). The
234 -- Related_Nod is the same as Decl_Node in Create_Constrained_Components.
235 -- The For_Access says whether or not this subtype is really constraining
236 -- an access type. That is its sole purpose is the designated type of an
237 -- access type -- in which case a Private_Subtype Is_For_Access_Subtype
238 -- is built to avoid freezing T when the access subtype is frozen.
240 function Build_Scalar_Bound
243 Der_T : Entity_Id) return Node_Id;
244 -- The bounds of a derived scalar type are conversions of the bounds of
245 -- the parent type. Optimize the representation if the bounds are literals.
246 -- Needs a more complete spec--what are the parameters exactly, and what
247 -- exactly is the returned value, and how is Bound affected???
249 procedure Build_Underlying_Full_View
253 -- If the completion of a private type is itself derived from a private
254 -- type, or if the full view of a private subtype is itself private, the
255 -- back-end has no way to compute the actual size of this type. We build
256 -- an internal subtype declaration of the proper parent type to convey
257 -- this information. This extra mechanism is needed because a full
258 -- view cannot itself have a full view (it would get clobbered during
261 procedure Check_Access_Discriminant_Requires_Limited
264 -- Check the restriction that the type to which an access discriminant
265 -- belongs must be a concurrent type or a descendant of a type with
266 -- the reserved word 'limited' in its declaration.
268 procedure Check_Anonymous_Access_Components
272 Comp_List : Node_Id);
273 -- Ada 2005 AI-382: an access component in a record definition can refer to
274 -- the enclosing record, in which case it denotes the type itself, and not
275 -- the current instance of the type. We create an anonymous access type for
276 -- the component, and flag it as an access to a component, so accessibility
277 -- checks are properly performed on it. The declaration of the access type
278 -- is placed ahead of that of the record to prevent order-of-elaboration
279 -- circularity issues in Gigi. We create an incomplete type for the record
280 -- declaration, which is the designated type of the anonymous access.
282 procedure Check_Delta_Expression (E : Node_Id);
283 -- Check that the expression represented by E is suitable for use as a
284 -- delta expression, i.e. it is of real type and is static.
286 procedure Check_Digits_Expression (E : Node_Id);
287 -- Check that the expression represented by E is suitable for use as a
288 -- digits expression, i.e. it is of integer type, positive and static.
290 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id);
291 -- Validate the initialization of an object declaration. T is the required
292 -- type, and Exp is the initialization expression.
294 procedure Check_Interfaces (N : Node_Id; Def : Node_Id);
295 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
297 procedure Check_Or_Process_Discriminants
300 Prev : Entity_Id := Empty);
301 -- If N is the full declaration of the completion T of an incomplete or
302 -- private type, check its discriminants (which are already known to be
303 -- conformant with those of the partial view, see Find_Type_Name),
304 -- otherwise process them. Prev is the entity of the partial declaration,
307 procedure Check_Real_Bound (Bound : Node_Id);
308 -- Check given bound for being of real type and static. If not, post an
309 -- appropriate message, and rewrite the bound with the real literal zero.
311 procedure Constant_Redeclaration
315 -- Various checks on legality of full declaration of deferred constant.
316 -- Id is the entity for the redeclaration, N is the N_Object_Declaration,
317 -- node. The caller has not yet set any attributes of this entity.
319 function Contain_Interface
321 Ifaces : Elist_Id) return Boolean;
322 -- Ada 2005: Determine whether Iface is present in the list Ifaces
324 procedure Convert_Scalar_Bounds
326 Parent_Type : Entity_Id;
327 Derived_Type : Entity_Id;
329 -- For derived scalar types, convert the bounds in the type definition to
330 -- the derived type, and complete their analysis. Given a constraint of the
331 -- form ".. new T range Lo .. Hi", Lo and Hi are analyzed and resolved with
332 -- T'Base, the parent_type. The bounds of the derived type (the anonymous
333 -- base) are copies of Lo and Hi. Finally, the bounds of the derived
334 -- subtype are conversions of those bounds to the derived_type, so that
335 -- their typing is consistent.
337 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id);
338 -- Copies attributes from array base type T2 to array base type T1. Copies
339 -- only attributes that apply to base types, but not subtypes.
341 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id);
342 -- Copies attributes from array subtype T2 to array subtype T1. Copies
343 -- attributes that apply to both subtypes and base types.
345 procedure Create_Constrained_Components
349 Constraints : Elist_Id);
350 -- Build the list of entities for a constrained discriminated record
351 -- subtype. If a component depends on a discriminant, replace its subtype
352 -- using the discriminant values in the discriminant constraint. Subt
353 -- is the defining identifier for the subtype whose list of constrained
354 -- entities we will create. Decl_Node is the type declaration node where
355 -- we will attach all the itypes created. Typ is the base discriminated
356 -- type for the subtype Subt. Constraints is the list of discriminant
357 -- constraints for Typ.
359 function Constrain_Component_Type
361 Constrained_Typ : Entity_Id;
362 Related_Node : Node_Id;
364 Constraints : Elist_Id) return Entity_Id;
365 -- Given a discriminated base type Typ, a list of discriminant constraints,
366 -- Constraints, for Typ and a component Comp of Typ, create and return the
367 -- type corresponding to Etype (Comp) where all discriminant references
368 -- are replaced with the corresponding constraint. If Etype (Comp) contains
369 -- no discriminant references then it is returned as-is. Constrained_Typ
370 -- is the final constrained subtype to which the constrained component
371 -- belongs. Related_Node is the node where we attach all created itypes.
373 procedure Constrain_Access
374 (Def_Id : in out Entity_Id;
376 Related_Nod : Node_Id);
377 -- Apply a list of constraints to an access type. If Def_Id is empty, it is
378 -- an anonymous type created for a subtype indication. In that case it is
379 -- created in the procedure and attached to Related_Nod.
381 procedure Constrain_Array
382 (Def_Id : in out Entity_Id;
384 Related_Nod : Node_Id;
385 Related_Id : Entity_Id;
387 -- Apply a list of index constraints to an unconstrained array type. The
388 -- first parameter is the entity for the resulting subtype. A value of
389 -- Empty for Def_Id indicates that an implicit type must be created, but
390 -- creation is delayed (and must be done by this procedure) because other
391 -- subsidiary implicit types must be created first (which is why Def_Id
392 -- is an in/out parameter). The second parameter is a subtype indication
393 -- node for the constrained array to be created (e.g. something of the
394 -- form string (1 .. 10)). Related_Nod gives the place where this type
395 -- has to be inserted in the tree. The Related_Id and Suffix parameters
396 -- are used to build the associated Implicit type name.
398 procedure Constrain_Concurrent
399 (Def_Id : in out Entity_Id;
401 Related_Nod : Node_Id;
402 Related_Id : Entity_Id;
404 -- Apply list of discriminant constraints to an unconstrained concurrent
407 -- SI is the N_Subtype_Indication node containing the constraint and
408 -- the unconstrained type to constrain.
410 -- Def_Id is the entity for the resulting constrained subtype. A value
411 -- of Empty for Def_Id indicates that an implicit type must be created,
412 -- but creation is delayed (and must be done by this procedure) because
413 -- other subsidiary implicit types must be created first (which is why
414 -- Def_Id is an in/out parameter).
416 -- Related_Nod gives the place where this type has to be inserted
419 -- The last two arguments are used to create its external name if needed.
421 function Constrain_Corresponding_Record
422 (Prot_Subt : Entity_Id;
423 Corr_Rec : Entity_Id;
424 Related_Nod : Node_Id) return Entity_Id;
425 -- When constraining a protected type or task type with discriminants,
426 -- constrain the corresponding record with the same discriminant values.
428 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id);
429 -- Constrain a decimal fixed point type with a digits constraint and/or a
430 -- range constraint, and build E_Decimal_Fixed_Point_Subtype entity.
432 procedure Constrain_Discriminated_Type
435 Related_Nod : Node_Id;
436 For_Access : Boolean := False);
437 -- Process discriminant constraints of composite type. Verify that values
438 -- have been provided for all discriminants, that the original type is
439 -- unconstrained, and that the types of the supplied expressions match
440 -- the discriminant types. The first three parameters are like in routine
441 -- Constrain_Concurrent. See Build_Discriminated_Subtype for an explanation
444 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id);
445 -- Constrain an enumeration type with a range constraint. This is identical
446 -- to Constrain_Integer, but for the Ekind of the resulting subtype.
448 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id);
449 -- Constrain a floating point type with either a digits constraint
450 -- and/or a range constraint, building a E_Floating_Point_Subtype.
452 procedure Constrain_Index
455 Related_Nod : Node_Id;
456 Related_Id : Entity_Id;
459 -- Process an index constraint S in a constrained array declaration. The
460 -- constraint can be a subtype name, or a range with or without an explicit
461 -- subtype mark. The index is the corresponding index of the unconstrained
462 -- array. The Related_Id and Suffix parameters are used to build the
463 -- associated Implicit type name.
465 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id);
466 -- Build subtype of a signed or modular integer type
468 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id);
469 -- Constrain an ordinary fixed point type with a range constraint, and
470 -- build an E_Ordinary_Fixed_Point_Subtype entity.
472 procedure Copy_And_Swap (Priv, Full : Entity_Id);
473 -- Copy the Priv entity into the entity of its full declaration then swap
474 -- the two entities in such a manner that the former private type is now
475 -- seen as a full type.
477 procedure Decimal_Fixed_Point_Type_Declaration
480 -- Create a new decimal fixed point type, and apply the constraint to
481 -- obtain a subtype of this new type.
483 procedure Complete_Private_Subtype
486 Full_Base : Entity_Id;
487 Related_Nod : Node_Id);
488 -- Complete the implicit full view of a private subtype by setting the
489 -- appropriate semantic fields. If the full view of the parent is a record
490 -- type, build constrained components of subtype.
492 procedure Derive_Progenitor_Subprograms
493 (Parent_Type : Entity_Id;
494 Tagged_Type : Entity_Id);
495 -- Ada 2005 (AI-251): To complete type derivation, collect the primitive
496 -- operations of progenitors of Tagged_Type, and replace the subsidiary
497 -- subtypes with Tagged_Type, to build the specs of the inherited interface
498 -- primitives. The derived primitives are aliased to those of the
499 -- interface. This routine takes care also of transferring to the full view
500 -- subprograms associated with the partial view of Tagged_Type that cover
501 -- interface primitives.
503 procedure Derived_Standard_Character
505 Parent_Type : Entity_Id;
506 Derived_Type : Entity_Id);
507 -- Subsidiary procedure to Build_Derived_Enumeration_Type which handles
508 -- derivations from types Standard.Character and Standard.Wide_Character.
510 procedure Derived_Type_Declaration
513 Is_Completion : Boolean);
514 -- Process a derived type declaration. Build_Derived_Type is invoked
515 -- to process the actual derived type definition. Parameters N and
516 -- Is_Completion have the same meaning as in Build_Derived_Type.
517 -- T is the N_Defining_Identifier for the entity defined in the
518 -- N_Full_Type_Declaration node N, that is T is the derived type.
520 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id);
521 -- Insert each literal in symbol table, as an overloadable identifier. Each
522 -- enumeration type is mapped into a sequence of integers, and each literal
523 -- is defined as a constant with integer value. If any of the literals are
524 -- character literals, the type is a character type, which means that
525 -- strings are legal aggregates for arrays of components of the type.
527 function Expand_To_Stored_Constraint
529 Constraint : Elist_Id) return Elist_Id;
530 -- Given a constraint (i.e. a list of expressions) on the discriminants of
531 -- Typ, expand it into a constraint on the stored discriminants and return
532 -- the new list of expressions constraining the stored discriminants.
534 function Find_Type_Of_Object
536 Related_Nod : Node_Id) return Entity_Id;
537 -- Get type entity for object referenced by Obj_Def, attaching the implicit
538 -- types generated to Related_Nod.
540 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id);
541 -- Create a new float and apply the constraint to obtain subtype of it
543 function Has_Range_Constraint (N : Node_Id) return Boolean;
544 -- Given an N_Subtype_Indication node N, return True if a range constraint
545 -- is present, either directly, or as part of a digits or delta constraint.
546 -- In addition, a digits constraint in the decimal case returns True, since
547 -- it establishes a default range if no explicit range is present.
549 function Inherit_Components
551 Parent_Base : Entity_Id;
552 Derived_Base : Entity_Id;
554 Inherit_Discr : Boolean;
555 Discs : Elist_Id) return Elist_Id;
556 -- Called from Build_Derived_Record_Type to inherit the components of
557 -- Parent_Base (a base type) into the Derived_Base (the derived base type).
558 -- For more information on derived types and component inheritance please
559 -- consult the comment above the body of Build_Derived_Record_Type.
561 -- N is the original derived type declaration
563 -- Is_Tagged is set if we are dealing with tagged types
565 -- If Inherit_Discr is set, Derived_Base inherits its discriminants from
566 -- Parent_Base, otherwise no discriminants are inherited.
568 -- Discs gives the list of constraints that apply to Parent_Base in the
569 -- derived type declaration. If Discs is set to No_Elist, then we have
570 -- the following situation:
572 -- type Parent (D1..Dn : ..) is [tagged] record ...;
573 -- type Derived is new Parent [with ...];
575 -- which gets treated as
577 -- type Derived (D1..Dn : ..) is new Parent (D1,..,Dn) [with ...];
579 -- For untagged types the returned value is an association list. The list
580 -- starts from the association (Parent_Base => Derived_Base), and then it
581 -- contains a sequence of the associations of the form
583 -- (Old_Component => New_Component),
585 -- where Old_Component is the Entity_Id of a component in Parent_Base and
586 -- New_Component is the Entity_Id of the corresponding component in
587 -- Derived_Base. For untagged records, this association list is needed when
588 -- copying the record declaration for the derived base. In the tagged case
589 -- the value returned is irrelevant.
591 procedure Inherit_Predicate_Flags (Subt, Par : Entity_Id);
592 -- Propagate static and dynamic predicate flags from a parent to the
593 -- subtype in a subtype declaration with and without constraints.
595 function Is_EVF_Procedure (Subp : Entity_Id) return Boolean;
596 -- Subsidiary to Check_Abstract_Overriding and Derive_Subprogram.
597 -- Determine whether subprogram Subp is a procedure subject to pragma
598 -- Extensions_Visible with value False and has at least one controlling
599 -- parameter of mode OUT.
601 function Is_Valid_Constraint_Kind
603 Constraint_Kind : Node_Kind) return Boolean;
604 -- Returns True if it is legal to apply the given kind of constraint to the
605 -- given kind of type (index constraint to an array type, for example).
607 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id);
608 -- Create new modular type. Verify that modulus is in bounds
610 procedure New_Concatenation_Op (Typ : Entity_Id);
611 -- Create an abbreviated declaration for an operator in order to
612 -- materialize concatenation on array types.
614 procedure Ordinary_Fixed_Point_Type_Declaration
617 -- Create a new ordinary fixed point type, and apply the constraint to
618 -- obtain subtype of it.
620 procedure Prepare_Private_Subtype_Completion
622 Related_Nod : Node_Id);
623 -- Id is a subtype of some private type. Creates the full declaration
624 -- associated with Id whenever possible, i.e. when the full declaration
625 -- of the base type is already known. Records each subtype into
626 -- Private_Dependents of the base type.
628 procedure Process_Incomplete_Dependents
632 -- Process all entities that depend on an incomplete type. There include
633 -- subtypes, subprogram types that mention the incomplete type in their
634 -- profiles, and subprogram with access parameters that designate the
637 -- Inc_T is the defining identifier of an incomplete type declaration, its
638 -- Ekind is E_Incomplete_Type.
640 -- N is the corresponding N_Full_Type_Declaration for Inc_T.
642 -- Full_T is N's defining identifier.
644 -- Subtypes of incomplete types with discriminants are completed when the
645 -- parent type is. This is simpler than private subtypes, because they can
646 -- only appear in the same scope, and there is no need to exchange views.
647 -- Similarly, access_to_subprogram types may have a parameter or a return
648 -- type that is an incomplete type, and that must be replaced with the
651 -- If the full type is tagged, subprogram with access parameters that
652 -- designated the incomplete may be primitive operations of the full type,
653 -- and have to be processed accordingly.
655 procedure Process_Real_Range_Specification (Def : Node_Id);
656 -- Given the type definition for a real type, this procedure processes and
657 -- checks the real range specification of this type definition if one is
658 -- present. If errors are found, error messages are posted, and the
659 -- Real_Range_Specification of Def is reset to Empty.
661 procedure Propagate_Default_Init_Cond_Attributes
662 (From_Typ : Entity_Id;
664 Parent_To_Derivation : Boolean := False;
665 Private_To_Full_View : Boolean := False);
666 -- Subsidiary to routines Build_Derived_Type and Process_Full_View. Inherit
667 -- all attributes related to pragma Default_Initial_Condition from From_Typ
668 -- to To_Typ. Flag Parent_To_Derivation should be set when the context is
669 -- the creation of a derived type. Flag Private_To_Full_View should be set
670 -- when processing both views of a private type.
672 procedure Record_Type_Declaration
676 -- Process a record type declaration (for both untagged and tagged
677 -- records). Parameters T and N are exactly like in procedure
678 -- Derived_Type_Declaration, except that no flag Is_Completion is needed
679 -- for this routine. If this is the completion of an incomplete type
680 -- declaration, Prev is the entity of the incomplete declaration, used for
681 -- cross-referencing. Otherwise Prev = T.
683 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id);
684 -- This routine is used to process the actual record type definition (both
685 -- for untagged and tagged records). Def is a record type definition node.
686 -- This procedure analyzes the components in this record type definition.
687 -- Prev_T is the entity for the enclosing record type. It is provided so
688 -- that its Has_Task flag can be set if any of the component have Has_Task
689 -- set. If the declaration is the completion of an incomplete type
690 -- declaration, Prev_T is the original incomplete type, whose full view is
693 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id);
694 -- Subsidiary to Build_Derived_Record_Type. For untagged records, we
695 -- build a copy of the declaration tree of the parent, and we create
696 -- independently the list of components for the derived type. Semantic
697 -- information uses the component entities, but record representation
698 -- clauses are validated on the declaration tree. This procedure replaces
699 -- discriminants and components in the declaration with those that have
700 -- been created by Inherit_Components.
702 procedure Set_Fixed_Range
707 -- Build a range node with the given bounds and set it as the Scalar_Range
708 -- of the given fixed-point type entity. Loc is the source location used
709 -- for the constructed range. See body for further details.
711 procedure Set_Scalar_Range_For_Subtype
715 -- This routine is used to set the scalar range field for a subtype given
716 -- Def_Id, the entity for the subtype, and R, the range expression for the
717 -- scalar range. Subt provides the parent subtype to be used to analyze,
718 -- resolve, and check the given range.
720 procedure Set_Default_SSO (T : Entity_Id);
721 -- T is the entity for an array or record being declared. This procedure
722 -- sets the flags SSO_Set_Low_By_Default/SSO_Set_High_By_Default according
723 -- to the setting of Opt.Default_SSO.
725 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id);
726 -- Create a new signed integer entity, and apply the constraint to obtain
727 -- the required first named subtype of this type.
729 procedure Set_Stored_Constraint_From_Discriminant_Constraint
731 -- E is some record type. This routine computes E's Stored_Constraint
732 -- from its Discriminant_Constraint.
734 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id);
735 -- Check that an entity in a list of progenitors is an interface,
736 -- emit error otherwise.
738 -----------------------
739 -- Access_Definition --
740 -----------------------
742 function Access_Definition
743 (Related_Nod : Node_Id;
744 N : Node_Id) return Entity_Id
746 Anon_Type : Entity_Id;
747 Anon_Scope : Entity_Id;
748 Desig_Type : Entity_Id;
749 Enclosing_Prot_Type : Entity_Id := Empty;
752 Check_SPARK_05_Restriction ("access type is not allowed", N);
754 if Is_Entry (Current_Scope)
755 and then Is_Task_Type (Etype (Scope (Current_Scope)))
757 Error_Msg_N ("task entries cannot have access parameters", N);
761 -- Ada 2005: For an object declaration the corresponding anonymous
762 -- type is declared in the current scope.
764 -- If the access definition is the return type of another access to
765 -- function, scope is the current one, because it is the one of the
766 -- current type declaration, except for the pathological case below.
768 if Nkind_In (Related_Nod, N_Object_Declaration,
769 N_Access_Function_Definition)
771 Anon_Scope := Current_Scope;
773 -- A pathological case: function returning access functions that
774 -- return access functions, etc. Each anonymous access type created
775 -- is in the enclosing scope of the outermost function.
782 while Nkind_In (Par, N_Access_Function_Definition,
788 if Nkind (Par) = N_Function_Specification then
789 Anon_Scope := Scope (Defining_Entity (Par));
793 -- For the anonymous function result case, retrieve the scope of the
794 -- function specification's associated entity rather than using the
795 -- current scope. The current scope will be the function itself if the
796 -- formal part is currently being analyzed, but will be the parent scope
797 -- in the case of a parameterless function, and we always want to use
798 -- the function's parent scope. Finally, if the function is a child
799 -- unit, we must traverse the tree to retrieve the proper entity.
801 elsif Nkind (Related_Nod) = N_Function_Specification
802 and then Nkind (Parent (N)) /= N_Parameter_Specification
804 -- If the current scope is a protected type, the anonymous access
805 -- is associated with one of the protected operations, and must
806 -- be available in the scope that encloses the protected declaration.
807 -- Otherwise the type is in the scope enclosing the subprogram.
809 -- If the function has formals, The return type of a subprogram
810 -- declaration is analyzed in the scope of the subprogram (see
811 -- Process_Formals) and thus the protected type, if present, is
812 -- the scope of the current function scope.
814 if Ekind (Current_Scope) = E_Protected_Type then
815 Enclosing_Prot_Type := Current_Scope;
817 elsif Ekind (Current_Scope) = E_Function
818 and then Ekind (Scope (Current_Scope)) = E_Protected_Type
820 Enclosing_Prot_Type := Scope (Current_Scope);
823 if Present (Enclosing_Prot_Type) then
824 Anon_Scope := Scope (Enclosing_Prot_Type);
827 Anon_Scope := Scope (Defining_Entity (Related_Nod));
830 -- For an access type definition, if the current scope is a child
831 -- unit it is the scope of the type.
833 elsif Is_Compilation_Unit (Current_Scope) then
834 Anon_Scope := Current_Scope;
836 -- For access formals, access components, and access discriminants, the
837 -- scope is that of the enclosing declaration,
840 Anon_Scope := Scope (Current_Scope);
845 (E_Anonymous_Access_Type, Related_Nod, Scope_Id => Anon_Scope);
848 and then Ada_Version >= Ada_2005
850 Error_Msg_N ("ALL is not permitted for anonymous access types", N);
853 -- Ada 2005 (AI-254): In case of anonymous access to subprograms call
854 -- the corresponding semantic routine
856 if Present (Access_To_Subprogram_Definition (N)) then
858 -- Compiler runtime units are compiled in Ada 2005 mode when building
859 -- the runtime library but must also be compilable in Ada 95 mode
860 -- (when bootstrapping the compiler).
862 Check_Compiler_Unit ("anonymous access to subprogram", N);
864 Access_Subprogram_Declaration
865 (T_Name => Anon_Type,
866 T_Def => Access_To_Subprogram_Definition (N));
868 if Ekind (Anon_Type) = E_Access_Protected_Subprogram_Type then
870 (Anon_Type, E_Anonymous_Access_Protected_Subprogram_Type);
872 Set_Ekind (Anon_Type, E_Anonymous_Access_Subprogram_Type);
875 Set_Can_Use_Internal_Rep
876 (Anon_Type, not Always_Compatible_Rep_On_Target);
878 -- If the anonymous access is associated with a protected operation,
879 -- create a reference to it after the enclosing protected definition
880 -- because the itype will be used in the subsequent bodies.
882 -- If the anonymous access itself is protected, a full type
883 -- declaratiton will be created for it, so that the equivalent
884 -- record type can be constructed. For further details, see
885 -- Replace_Anonymous_Access_To_Protected-Subprogram.
887 if Ekind (Current_Scope) = E_Protected_Type
888 and then not Protected_Present (Access_To_Subprogram_Definition (N))
890 Build_Itype_Reference (Anon_Type, Parent (Current_Scope));
896 Find_Type (Subtype_Mark (N));
897 Desig_Type := Entity (Subtype_Mark (N));
899 Set_Directly_Designated_Type (Anon_Type, Desig_Type);
900 Set_Etype (Anon_Type, Anon_Type);
902 -- Make sure the anonymous access type has size and alignment fields
903 -- set, as required by gigi. This is necessary in the case of the
904 -- Task_Body_Procedure.
906 if not Has_Private_Component (Desig_Type) then
907 Layout_Type (Anon_Type);
910 -- Ada 2005 (AI-231): Ada 2005 semantics for anonymous access differs
911 -- from Ada 95 semantics. In Ada 2005, anonymous access must specify if
912 -- the null value is allowed. In Ada 95 the null value is never allowed.
914 if Ada_Version >= Ada_2005 then
915 Set_Can_Never_Be_Null (Anon_Type, Null_Exclusion_Present (N));
917 Set_Can_Never_Be_Null (Anon_Type, True);
920 -- The anonymous access type is as public as the discriminated type or
921 -- subprogram that defines it. It is imported (for back-end purposes)
922 -- if the designated type is.
924 Set_Is_Public (Anon_Type, Is_Public (Scope (Anon_Type)));
926 -- Ada 2005 (AI-231): Propagate the access-constant attribute
928 Set_Is_Access_Constant (Anon_Type, Constant_Present (N));
930 -- The context is either a subprogram declaration, object declaration,
931 -- or an access discriminant, in a private or a full type declaration.
932 -- In the case of a subprogram, if the designated type is incomplete,
933 -- the operation will be a primitive operation of the full type, to be
934 -- updated subsequently. If the type is imported through a limited_with
935 -- clause, the subprogram is not a primitive operation of the type
936 -- (which is declared elsewhere in some other scope).
938 if Ekind (Desig_Type) = E_Incomplete_Type
939 and then not From_Limited_With (Desig_Type)
940 and then Is_Overloadable (Current_Scope)
942 Append_Elmt (Current_Scope, Private_Dependents (Desig_Type));
943 Set_Has_Delayed_Freeze (Current_Scope);
946 -- Ada 2005: If the designated type is an interface that may contain
947 -- tasks, create a Master entity for the declaration. This must be done
948 -- before expansion of the full declaration, because the declaration may
949 -- include an expression that is an allocator, whose expansion needs the
950 -- proper Master for the created tasks.
952 if Nkind (Related_Nod) = N_Object_Declaration and then Expander_Active
954 if Is_Interface (Desig_Type) and then Is_Limited_Record (Desig_Type)
956 Build_Class_Wide_Master (Anon_Type);
958 -- Similarly, if the type is an anonymous access that designates
959 -- tasks, create a master entity for it in the current context.
961 elsif Has_Task (Desig_Type) and then Comes_From_Source (Related_Nod)
963 Build_Master_Entity (Defining_Identifier (Related_Nod));
964 Build_Master_Renaming (Anon_Type);
968 -- For a private component of a protected type, it is imperative that
969 -- the back-end elaborate the type immediately after the protected
970 -- declaration, because this type will be used in the declarations
971 -- created for the component within each protected body, so we must
972 -- create an itype reference for it now.
974 if Nkind (Parent (Related_Nod)) = N_Protected_Definition then
975 Build_Itype_Reference (Anon_Type, Parent (Parent (Related_Nod)));
977 -- Similarly, if the access definition is the return result of a
978 -- function, create an itype reference for it because it will be used
979 -- within the function body. For a regular function that is not a
980 -- compilation unit, insert reference after the declaration. For a
981 -- protected operation, insert it after the enclosing protected type
982 -- declaration. In either case, do not create a reference for a type
983 -- obtained through a limited_with clause, because this would introduce
984 -- semantic dependencies.
986 -- Similarly, do not create a reference if the designated type is a
987 -- generic formal, because no use of it will reach the backend.
989 elsif Nkind (Related_Nod) = N_Function_Specification
990 and then not From_Limited_With (Desig_Type)
991 and then not Is_Generic_Type (Desig_Type)
993 if Present (Enclosing_Prot_Type) then
994 Build_Itype_Reference (Anon_Type, Parent (Enclosing_Prot_Type));
996 elsif Is_List_Member (Parent (Related_Nod))
997 and then Nkind (Parent (N)) /= N_Parameter_Specification
999 Build_Itype_Reference (Anon_Type, Parent (Related_Nod));
1002 -- Finally, create an itype reference for an object declaration of an
1003 -- anonymous access type. This is strictly necessary only for deferred
1004 -- constants, but in any case will avoid out-of-scope problems in the
1007 elsif Nkind (Related_Nod) = N_Object_Declaration then
1008 Build_Itype_Reference (Anon_Type, Related_Nod);
1012 end Access_Definition;
1014 -----------------------------------
1015 -- Access_Subprogram_Declaration --
1016 -----------------------------------
1018 procedure Access_Subprogram_Declaration
1019 (T_Name : Entity_Id;
1022 procedure Check_For_Premature_Usage (Def : Node_Id);
1023 -- Check that type T_Name is not used, directly or recursively, as a
1024 -- parameter or a return type in Def. Def is either a subtype, an
1025 -- access_definition, or an access_to_subprogram_definition.
1027 -------------------------------
1028 -- Check_For_Premature_Usage --
1029 -------------------------------
1031 procedure Check_For_Premature_Usage (Def : Node_Id) is
1035 -- Check for a subtype mark
1037 if Nkind (Def) in N_Has_Etype then
1038 if Etype (Def) = T_Name then
1040 ("type& cannot be used before end of its declaration", Def);
1043 -- If this is not a subtype, then this is an access_definition
1045 elsif Nkind (Def) = N_Access_Definition then
1046 if Present (Access_To_Subprogram_Definition (Def)) then
1047 Check_For_Premature_Usage
1048 (Access_To_Subprogram_Definition (Def));
1050 Check_For_Premature_Usage (Subtype_Mark (Def));
1053 -- The only cases left are N_Access_Function_Definition and
1054 -- N_Access_Procedure_Definition.
1057 if Present (Parameter_Specifications (Def)) then
1058 Param := First (Parameter_Specifications (Def));
1059 while Present (Param) loop
1060 Check_For_Premature_Usage (Parameter_Type (Param));
1061 Param := Next (Param);
1065 if Nkind (Def) = N_Access_Function_Definition then
1066 Check_For_Premature_Usage (Result_Definition (Def));
1069 end Check_For_Premature_Usage;
1073 Formals : constant List_Id := Parameter_Specifications (T_Def);
1076 Desig_Type : constant Entity_Id :=
1077 Create_Itype (E_Subprogram_Type, Parent (T_Def));
1079 -- Start of processing for Access_Subprogram_Declaration
1082 Check_SPARK_05_Restriction ("access type is not allowed", T_Def);
1084 -- Associate the Itype node with the inner full-type declaration or
1085 -- subprogram spec or entry body. This is required to handle nested
1086 -- anonymous declarations. For example:
1089 -- (X : access procedure
1090 -- (Y : access procedure
1093 D_Ityp := Associated_Node_For_Itype (Desig_Type);
1094 while not (Nkind_In (D_Ityp, N_Full_Type_Declaration,
1095 N_Private_Type_Declaration,
1096 N_Private_Extension_Declaration,
1097 N_Procedure_Specification,
1098 N_Function_Specification,
1102 Nkind_In (D_Ityp, N_Object_Declaration,
1103 N_Object_Renaming_Declaration,
1104 N_Formal_Object_Declaration,
1105 N_Formal_Type_Declaration,
1106 N_Task_Type_Declaration,
1107 N_Protected_Type_Declaration))
1109 D_Ityp := Parent (D_Ityp);
1110 pragma Assert (D_Ityp /= Empty);
1113 Set_Associated_Node_For_Itype (Desig_Type, D_Ityp);
1115 if Nkind_In (D_Ityp, N_Procedure_Specification,
1116 N_Function_Specification)
1118 Set_Scope (Desig_Type, Scope (Defining_Entity (D_Ityp)));
1120 elsif Nkind_In (D_Ityp, N_Full_Type_Declaration,
1121 N_Object_Declaration,
1122 N_Object_Renaming_Declaration,
1123 N_Formal_Type_Declaration)
1125 Set_Scope (Desig_Type, Scope (Defining_Identifier (D_Ityp)));
1128 if Nkind (T_Def) = N_Access_Function_Definition then
1129 if Nkind (Result_Definition (T_Def)) = N_Access_Definition then
1131 Acc : constant Node_Id := Result_Definition (T_Def);
1134 if Present (Access_To_Subprogram_Definition (Acc))
1136 Protected_Present (Access_To_Subprogram_Definition (Acc))
1140 Replace_Anonymous_Access_To_Protected_Subprogram
1146 Access_Definition (T_Def, Result_Definition (T_Def)));
1151 Analyze (Result_Definition (T_Def));
1154 Typ : constant Entity_Id := Entity (Result_Definition (T_Def));
1157 -- If a null exclusion is imposed on the result type, then
1158 -- create a null-excluding itype (an access subtype) and use
1159 -- it as the function's Etype.
1161 if Is_Access_Type (Typ)
1162 and then Null_Exclusion_In_Return_Present (T_Def)
1164 Set_Etype (Desig_Type,
1165 Create_Null_Excluding_Itype
1167 Related_Nod => T_Def,
1168 Scope_Id => Current_Scope));
1171 if From_Limited_With (Typ) then
1173 -- AI05-151: Incomplete types are allowed in all basic
1174 -- declarations, including access to subprograms.
1176 if Ada_Version >= Ada_2012 then
1181 ("illegal use of incomplete type&",
1182 Result_Definition (T_Def), Typ);
1185 elsif Ekind (Current_Scope) = E_Package
1186 and then In_Private_Part (Current_Scope)
1188 if Ekind (Typ) = E_Incomplete_Type then
1189 Append_Elmt (Desig_Type, Private_Dependents (Typ));
1191 elsif Is_Class_Wide_Type (Typ)
1192 and then Ekind (Etype (Typ)) = E_Incomplete_Type
1195 (Desig_Type, Private_Dependents (Etype (Typ)));
1199 Set_Etype (Desig_Type, Typ);
1204 if not (Is_Type (Etype (Desig_Type))) then
1206 ("expect type in function specification",
1207 Result_Definition (T_Def));
1211 Set_Etype (Desig_Type, Standard_Void_Type);
1214 if Present (Formals) then
1215 Push_Scope (Desig_Type);
1217 -- Some special tests here. These special tests can be removed
1218 -- if and when Itypes always have proper parent pointers to their
1221 -- Special test 1) Link defining_identifier of formals. Required by
1222 -- First_Formal to provide its functionality.
1228 F := First (Formals);
1230 -- In ASIS mode, the access_to_subprogram may be analyzed twice,
1231 -- when it is part of an unconstrained type and subtype expansion
1232 -- is disabled. To avoid back-end problems with shared profiles,
1233 -- use previous subprogram type as the designated type, and then
1234 -- remove scope added above.
1236 if ASIS_Mode and then Present (Scope (Defining_Identifier (F)))
1238 Set_Etype (T_Name, T_Name);
1239 Init_Size_Align (T_Name);
1240 Set_Directly_Designated_Type (T_Name,
1241 Scope (Defining_Identifier (F)));
1246 while Present (F) loop
1247 if No (Parent (Defining_Identifier (F))) then
1248 Set_Parent (Defining_Identifier (F), F);
1255 Process_Formals (Formals, Parent (T_Def));
1257 -- Special test 2) End_Scope requires that the parent pointer be set
1258 -- to something reasonable, but Itypes don't have parent pointers. So
1259 -- we set it and then unset it ???
1261 Set_Parent (Desig_Type, T_Name);
1263 Set_Parent (Desig_Type, Empty);
1266 -- Check for premature usage of the type being defined
1268 Check_For_Premature_Usage (T_Def);
1270 -- The return type and/or any parameter type may be incomplete. Mark the
1271 -- subprogram_type as depending on the incomplete type, so that it can
1272 -- be updated when the full type declaration is seen. This only applies
1273 -- to incomplete types declared in some enclosing scope, not to limited
1274 -- views from other packages.
1276 -- Prior to Ada 2012, access to functions can only have in_parameters.
1278 if Present (Formals) then
1279 Formal := First_Formal (Desig_Type);
1280 while Present (Formal) loop
1281 if Ekind (Formal) /= E_In_Parameter
1282 and then Nkind (T_Def) = N_Access_Function_Definition
1283 and then Ada_Version < Ada_2012
1285 Error_Msg_N ("functions can only have IN parameters", Formal);
1288 if Ekind (Etype (Formal)) = E_Incomplete_Type
1289 and then In_Open_Scopes (Scope (Etype (Formal)))
1291 Append_Elmt (Desig_Type, Private_Dependents (Etype (Formal)));
1292 Set_Has_Delayed_Freeze (Desig_Type);
1295 Next_Formal (Formal);
1299 -- Check whether an indirect call without actuals may be possible. This
1300 -- is used when resolving calls whose result is then indexed.
1302 May_Need_Actuals (Desig_Type);
1304 -- If the return type is incomplete, this is legal as long as the type
1305 -- is declared in the current scope and will be completed in it (rather
1306 -- than being part of limited view).
1308 if Ekind (Etype (Desig_Type)) = E_Incomplete_Type
1309 and then not Has_Delayed_Freeze (Desig_Type)
1310 and then In_Open_Scopes (Scope (Etype (Desig_Type)))
1312 Append_Elmt (Desig_Type, Private_Dependents (Etype (Desig_Type)));
1313 Set_Has_Delayed_Freeze (Desig_Type);
1316 Check_Delayed_Subprogram (Desig_Type);
1318 if Protected_Present (T_Def) then
1319 Set_Ekind (T_Name, E_Access_Protected_Subprogram_Type);
1320 Set_Convention (Desig_Type, Convention_Protected);
1322 Set_Ekind (T_Name, E_Access_Subprogram_Type);
1325 Set_Can_Use_Internal_Rep (T_Name, not Always_Compatible_Rep_On_Target);
1327 Set_Etype (T_Name, T_Name);
1328 Init_Size_Align (T_Name);
1329 Set_Directly_Designated_Type (T_Name, Desig_Type);
1331 Generate_Reference_To_Formals (T_Name);
1333 -- Ada 2005 (AI-231): Propagate the null-excluding attribute
1335 Set_Can_Never_Be_Null (T_Name, Null_Exclusion_Present (T_Def));
1337 Check_Restriction (No_Access_Subprograms, T_Def);
1338 end Access_Subprogram_Declaration;
1340 ----------------------------
1341 -- Access_Type_Declaration --
1342 ----------------------------
1344 procedure Access_Type_Declaration (T : Entity_Id; Def : Node_Id) is
1345 P : constant Node_Id := Parent (Def);
1346 S : constant Node_Id := Subtype_Indication (Def);
1348 Full_Desig : Entity_Id;
1351 Check_SPARK_05_Restriction ("access type is not allowed", Def);
1353 -- Check for permissible use of incomplete type
1355 if Nkind (S) /= N_Subtype_Indication then
1358 if Ekind (Root_Type (Entity (S))) = E_Incomplete_Type then
1359 Set_Directly_Designated_Type (T, Entity (S));
1361 -- If the designated type is a limited view, we cannot tell if
1362 -- the full view contains tasks, and there is no way to handle
1363 -- that full view in a client. We create a master entity for the
1364 -- scope, which will be used when a client determines that one
1367 if From_Limited_With (Entity (S))
1368 and then not Is_Class_Wide_Type (Entity (S))
1370 Set_Ekind (T, E_Access_Type);
1371 Build_Master_Entity (T);
1372 Build_Master_Renaming (T);
1376 Set_Directly_Designated_Type (T, Process_Subtype (S, P, T, 'P'));
1379 -- If the access definition is of the form: ACCESS NOT NULL ..
1380 -- the subtype indication must be of an access type. Create
1381 -- a null-excluding subtype of it.
1383 if Null_Excluding_Subtype (Def) then
1384 if not Is_Access_Type (Entity (S)) then
1385 Error_Msg_N ("null exclusion must apply to access type", Def);
1389 Loc : constant Source_Ptr := Sloc (S);
1391 Nam : constant Entity_Id := Make_Temporary (Loc, 'S');
1395 Make_Subtype_Declaration (Loc,
1396 Defining_Identifier => Nam,
1397 Subtype_Indication =>
1398 New_Occurrence_Of (Entity (S), Loc));
1399 Set_Null_Exclusion_Present (Decl);
1400 Insert_Before (Parent (Def), Decl);
1402 Set_Entity (S, Nam);
1408 Set_Directly_Designated_Type (T,
1409 Process_Subtype (S, P, T, 'P'));
1412 if All_Present (Def) or Constant_Present (Def) then
1413 Set_Ekind (T, E_General_Access_Type);
1415 Set_Ekind (T, E_Access_Type);
1418 Full_Desig := Designated_Type (T);
1420 if Base_Type (Full_Desig) = T then
1421 Error_Msg_N ("access type cannot designate itself", S);
1423 -- In Ada 2005, the type may have a limited view through some unit in
1424 -- its own context, allowing the following circularity that cannot be
1425 -- detected earlier.
1427 elsif Is_Class_Wide_Type (Full_Desig) and then Etype (Full_Desig) = T
1430 ("access type cannot designate its own classwide type", S);
1432 -- Clean up indication of tagged status to prevent cascaded errors
1434 Set_Is_Tagged_Type (T, False);
1439 -- If the type has appeared already in a with_type clause, it is frozen
1440 -- and the pointer size is already set. Else, initialize.
1442 if not From_Limited_With (T) then
1443 Init_Size_Align (T);
1446 -- Note that Has_Task is always false, since the access type itself
1447 -- is not a task type. See Einfo for more description on this point.
1448 -- Exactly the same consideration applies to Has_Controlled_Component
1449 -- and to Has_Protected.
1451 Set_Has_Task (T, False);
1452 Set_Has_Controlled_Component (T, False);
1453 Set_Has_Protected (T, False);
1455 -- Initialize field Finalization_Master explicitly to Empty, to avoid
1456 -- problems where an incomplete view of this entity has been previously
1457 -- established by a limited with and an overlaid version of this field
1458 -- (Stored_Constraint) was initialized for the incomplete view.
1460 -- This reset is performed in most cases except where the access type
1461 -- has been created for the purposes of allocating or deallocating a
1462 -- build-in-place object. Such access types have explicitly set pools
1463 -- and finalization masters.
1465 if No (Associated_Storage_Pool (T)) then
1466 Set_Finalization_Master (T, Empty);
1469 -- Ada 2005 (AI-231): Propagate the null-excluding and access-constant
1472 Set_Can_Never_Be_Null (T, Null_Exclusion_Present (Def));
1473 Set_Is_Access_Constant (T, Constant_Present (Def));
1474 end Access_Type_Declaration;
1476 ----------------------------------
1477 -- Add_Interface_Tag_Components --
1478 ----------------------------------
1480 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id) is
1481 Loc : constant Source_Ptr := Sloc (N);
1485 procedure Add_Tag (Iface : Entity_Id);
1486 -- Add tag for one of the progenitor interfaces
1492 procedure Add_Tag (Iface : Entity_Id) is
1499 pragma Assert (Is_Tagged_Type (Iface) and then Is_Interface (Iface));
1501 -- This is a reasonable place to propagate predicates
1503 if Has_Predicates (Iface) then
1504 Set_Has_Predicates (Typ);
1508 Make_Component_Definition (Loc,
1509 Aliased_Present => True,
1510 Subtype_Indication =>
1511 New_Occurrence_Of (RTE (RE_Interface_Tag), Loc));
1513 Tag := Make_Temporary (Loc, 'V');
1516 Make_Component_Declaration (Loc,
1517 Defining_Identifier => Tag,
1518 Component_Definition => Def);
1520 Analyze_Component_Declaration (Decl);
1522 Set_Analyzed (Decl);
1523 Set_Ekind (Tag, E_Component);
1525 Set_Is_Aliased (Tag);
1526 Set_Related_Type (Tag, Iface);
1527 Init_Component_Location (Tag);
1529 pragma Assert (Is_Frozen (Iface));
1531 Set_DT_Entry_Count (Tag,
1532 DT_Entry_Count (First_Entity (Iface)));
1534 if No (Last_Tag) then
1537 Insert_After (Last_Tag, Decl);
1542 -- If the ancestor has discriminants we need to give special support
1543 -- to store the offset_to_top value of the secondary dispatch tables.
1544 -- For this purpose we add a supplementary component just after the
1545 -- field that contains the tag associated with each secondary DT.
1547 if Typ /= Etype (Typ) and then Has_Discriminants (Etype (Typ)) then
1549 Make_Component_Definition (Loc,
1550 Subtype_Indication =>
1551 New_Occurrence_Of (RTE (RE_Storage_Offset), Loc));
1553 Offset := Make_Temporary (Loc, 'V');
1556 Make_Component_Declaration (Loc,
1557 Defining_Identifier => Offset,
1558 Component_Definition => Def);
1560 Analyze_Component_Declaration (Decl);
1562 Set_Analyzed (Decl);
1563 Set_Ekind (Offset, E_Component);
1564 Set_Is_Aliased (Offset);
1565 Set_Related_Type (Offset, Iface);
1566 Init_Component_Location (Offset);
1567 Insert_After (Last_Tag, Decl);
1578 -- Start of processing for Add_Interface_Tag_Components
1581 if not RTE_Available (RE_Interface_Tag) then
1583 ("(Ada 2005) interface types not supported by this run-time!",
1588 if Ekind (Typ) /= E_Record_Type
1589 or else (Is_Concurrent_Record_Type (Typ)
1590 and then Is_Empty_List (Abstract_Interface_List (Typ)))
1591 or else (not Is_Concurrent_Record_Type (Typ)
1592 and then No (Interfaces (Typ))
1593 and then Is_Empty_Elmt_List (Interfaces (Typ)))
1598 -- Find the current last tag
1600 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1601 Ext := Record_Extension_Part (Type_Definition (N));
1603 pragma Assert (Nkind (Type_Definition (N)) = N_Record_Definition);
1604 Ext := Type_Definition (N);
1609 if not (Present (Component_List (Ext))) then
1610 Set_Null_Present (Ext, False);
1612 Set_Component_List (Ext,
1613 Make_Component_List (Loc,
1614 Component_Items => L,
1615 Null_Present => False));
1617 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1618 L := Component_Items
1620 (Record_Extension_Part
1621 (Type_Definition (N))));
1623 L := Component_Items
1625 (Type_Definition (N)));
1628 -- Find the last tag component
1631 while Present (Comp) loop
1632 if Nkind (Comp) = N_Component_Declaration
1633 and then Is_Tag (Defining_Identifier (Comp))
1642 -- At this point L references the list of components and Last_Tag
1643 -- references the current last tag (if any). Now we add the tag
1644 -- corresponding with all the interfaces that are not implemented
1647 if Present (Interfaces (Typ)) then
1648 Elmt := First_Elmt (Interfaces (Typ));
1649 while Present (Elmt) loop
1650 Add_Tag (Node (Elmt));
1654 end Add_Interface_Tag_Components;
1656 -------------------------------------
1657 -- Add_Internal_Interface_Entities --
1658 -------------------------------------
1660 procedure Add_Internal_Interface_Entities (Tagged_Type : Entity_Id) is
1663 Iface_Elmt : Elmt_Id;
1664 Iface_Prim : Entity_Id;
1665 Ifaces_List : Elist_Id;
1666 New_Subp : Entity_Id := Empty;
1668 Restore_Scope : Boolean := False;
1671 pragma Assert (Ada_Version >= Ada_2005
1672 and then Is_Record_Type (Tagged_Type)
1673 and then Is_Tagged_Type (Tagged_Type)
1674 and then Has_Interfaces (Tagged_Type)
1675 and then not Is_Interface (Tagged_Type));
1677 -- Ensure that the internal entities are added to the scope of the type
1679 if Scope (Tagged_Type) /= Current_Scope then
1680 Push_Scope (Scope (Tagged_Type));
1681 Restore_Scope := True;
1684 Collect_Interfaces (Tagged_Type, Ifaces_List);
1686 Iface_Elmt := First_Elmt (Ifaces_List);
1687 while Present (Iface_Elmt) loop
1688 Iface := Node (Iface_Elmt);
1690 -- Originally we excluded here from this processing interfaces that
1691 -- are parents of Tagged_Type because their primitives are located
1692 -- in the primary dispatch table (and hence no auxiliary internal
1693 -- entities are required to handle secondary dispatch tables in such
1694 -- case). However, these auxiliary entities are also required to
1695 -- handle derivations of interfaces in formals of generics (see
1696 -- Derive_Subprograms).
1698 Elmt := First_Elmt (Primitive_Operations (Iface));
1699 while Present (Elmt) loop
1700 Iface_Prim := Node (Elmt);
1702 if not Is_Predefined_Dispatching_Operation (Iface_Prim) then
1704 Find_Primitive_Covering_Interface
1705 (Tagged_Type => Tagged_Type,
1706 Iface_Prim => Iface_Prim);
1708 if No (Prim) and then Serious_Errors_Detected > 0 then
1712 pragma Assert (Present (Prim));
1714 -- Ada 2012 (AI05-0197): If the name of the covering primitive
1715 -- differs from the name of the interface primitive then it is
1716 -- a private primitive inherited from a parent type. In such
1717 -- case, given that Tagged_Type covers the interface, the
1718 -- inherited private primitive becomes visible. For such
1719 -- purpose we add a new entity that renames the inherited
1720 -- private primitive.
1722 if Chars (Prim) /= Chars (Iface_Prim) then
1723 pragma Assert (Has_Suffix (Prim, 'P'));
1725 (New_Subp => New_Subp,
1726 Parent_Subp => Iface_Prim,
1727 Derived_Type => Tagged_Type,
1728 Parent_Type => Iface);
1729 Set_Alias (New_Subp, Prim);
1730 Set_Is_Abstract_Subprogram
1731 (New_Subp, Is_Abstract_Subprogram (Prim));
1735 (New_Subp => New_Subp,
1736 Parent_Subp => Iface_Prim,
1737 Derived_Type => Tagged_Type,
1738 Parent_Type => Iface);
1740 -- Ada 2005 (AI-251): Decorate internal entity Iface_Subp
1741 -- associated with interface types. These entities are
1742 -- only registered in the list of primitives of its
1743 -- corresponding tagged type because they are only used
1744 -- to fill the contents of the secondary dispatch tables.
1745 -- Therefore they are removed from the homonym chains.
1747 Set_Is_Hidden (New_Subp);
1748 Set_Is_Internal (New_Subp);
1749 Set_Alias (New_Subp, Prim);
1750 Set_Is_Abstract_Subprogram
1751 (New_Subp, Is_Abstract_Subprogram (Prim));
1752 Set_Interface_Alias (New_Subp, Iface_Prim);
1754 -- If the returned type is an interface then propagate it to
1755 -- the returned type. Needed by the thunk to generate the code
1756 -- which displaces "this" to reference the corresponding
1757 -- secondary dispatch table in the returned object.
1759 if Is_Interface (Etype (Iface_Prim)) then
1760 Set_Etype (New_Subp, Etype (Iface_Prim));
1763 -- Internal entities associated with interface types are only
1764 -- registered in the list of primitives of the tagged type.
1765 -- They are only used to fill the contents of the secondary
1766 -- dispatch tables. Therefore they are not needed in the
1769 Remove_Homonym (New_Subp);
1771 -- Hidden entities associated with interfaces must have set
1772 -- the Has_Delay_Freeze attribute to ensure that, in case
1773 -- of locally defined tagged types (or compiling with static
1774 -- dispatch tables generation disabled) the corresponding
1775 -- entry of the secondary dispatch table is filled when such
1776 -- an entity is frozen. This is an expansion activity that must
1777 -- be suppressed for ASIS because it leads to gigi elaboration
1778 -- issues in annotate mode.
1780 if not ASIS_Mode then
1781 Set_Has_Delayed_Freeze (New_Subp);
1789 Next_Elmt (Iface_Elmt);
1792 if Restore_Scope then
1795 end Add_Internal_Interface_Entities;
1797 -----------------------------------
1798 -- Analyze_Component_Declaration --
1799 -----------------------------------
1801 procedure Analyze_Component_Declaration (N : Node_Id) is
1802 Loc : constant Source_Ptr := Sloc (Component_Definition (N));
1803 Id : constant Entity_Id := Defining_Identifier (N);
1804 E : constant Node_Id := Expression (N);
1805 Typ : constant Node_Id :=
1806 Subtype_Indication (Component_Definition (N));
1810 function Contains_POC (Constr : Node_Id) return Boolean;
1811 -- Determines whether a constraint uses the discriminant of a record
1812 -- type thus becoming a per-object constraint (POC).
1814 function Is_Known_Limited (Typ : Entity_Id) return Boolean;
1815 -- Typ is the type of the current component, check whether this type is
1816 -- a limited type. Used to validate declaration against that of
1817 -- enclosing record.
1823 function Contains_POC (Constr : Node_Id) return Boolean is
1825 -- Prevent cascaded errors
1827 if Error_Posted (Constr) then
1831 case Nkind (Constr) is
1832 when N_Attribute_Reference =>
1833 return Attribute_Name (Constr) = Name_Access
1834 and then Prefix (Constr) = Scope (Entity (Prefix (Constr)));
1836 when N_Discriminant_Association =>
1837 return Denotes_Discriminant (Expression (Constr));
1839 when N_Identifier =>
1840 return Denotes_Discriminant (Constr);
1842 when N_Index_Or_Discriminant_Constraint =>
1847 IDC := First (Constraints (Constr));
1848 while Present (IDC) loop
1850 -- One per-object constraint is sufficient
1852 if Contains_POC (IDC) then
1863 return Denotes_Discriminant (Low_Bound (Constr))
1865 Denotes_Discriminant (High_Bound (Constr));
1867 when N_Range_Constraint =>
1868 return Denotes_Discriminant (Range_Expression (Constr));
1876 ----------------------
1877 -- Is_Known_Limited --
1878 ----------------------
1880 function Is_Known_Limited (Typ : Entity_Id) return Boolean is
1881 P : constant Entity_Id := Etype (Typ);
1882 R : constant Entity_Id := Root_Type (Typ);
1885 if Is_Limited_Record (Typ) then
1888 -- If the root type is limited (and not a limited interface)
1889 -- so is the current type
1891 elsif Is_Limited_Record (R)
1892 and then (not Is_Interface (R) or else not Is_Limited_Interface (R))
1896 -- Else the type may have a limited interface progenitor, but a
1897 -- limited record parent.
1899 elsif R /= P and then Is_Limited_Record (P) then
1905 end Is_Known_Limited;
1907 -- Start of processing for Analyze_Component_Declaration
1910 Generate_Definition (Id);
1913 if Present (Typ) then
1914 T := Find_Type_Of_Object
1915 (Subtype_Indication (Component_Definition (N)), N);
1917 if not Nkind_In (Typ, N_Identifier, N_Expanded_Name) then
1918 Check_SPARK_05_Restriction ("subtype mark required", Typ);
1921 -- Ada 2005 (AI-230): Access Definition case
1924 pragma Assert (Present
1925 (Access_Definition (Component_Definition (N))));
1927 T := Access_Definition
1929 N => Access_Definition (Component_Definition (N)));
1930 Set_Is_Local_Anonymous_Access (T);
1932 -- Ada 2005 (AI-254)
1934 if Present (Access_To_Subprogram_Definition
1935 (Access_Definition (Component_Definition (N))))
1936 and then Protected_Present (Access_To_Subprogram_Definition
1938 (Component_Definition (N))))
1940 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1944 -- If the subtype is a constrained subtype of the enclosing record,
1945 -- (which must have a partial view) the back-end does not properly
1946 -- handle the recursion. Rewrite the component declaration with an
1947 -- explicit subtype indication, which is acceptable to Gigi. We can copy
1948 -- the tree directly because side effects have already been removed from
1949 -- discriminant constraints.
1951 if Ekind (T) = E_Access_Subtype
1952 and then Is_Entity_Name (Subtype_Indication (Component_Definition (N)))
1953 and then Comes_From_Source (T)
1954 and then Nkind (Parent (T)) = N_Subtype_Declaration
1955 and then Etype (Directly_Designated_Type (T)) = Current_Scope
1958 (Subtype_Indication (Component_Definition (N)),
1959 New_Copy_Tree (Subtype_Indication (Parent (T))));
1960 T := Find_Type_Of_Object
1961 (Subtype_Indication (Component_Definition (N)), N);
1964 -- If the component declaration includes a default expression, then we
1965 -- check that the component is not of a limited type (RM 3.7(5)),
1966 -- and do the special preanalysis of the expression (see section on
1967 -- "Handling of Default and Per-Object Expressions" in the spec of
1971 Check_SPARK_05_Restriction ("default expression is not allowed", E);
1972 Preanalyze_Default_Expression (E, T);
1973 Check_Initialization (T, E);
1975 if Ada_Version >= Ada_2005
1976 and then Ekind (T) = E_Anonymous_Access_Type
1977 and then Etype (E) /= Any_Type
1979 -- Check RM 3.9.2(9): "if the expected type for an expression is
1980 -- an anonymous access-to-specific tagged type, then the object
1981 -- designated by the expression shall not be dynamically tagged
1982 -- unless it is a controlling operand in a call on a dispatching
1985 if Is_Tagged_Type (Directly_Designated_Type (T))
1987 Ekind (Directly_Designated_Type (T)) /= E_Class_Wide_Type
1989 Ekind (Directly_Designated_Type (Etype (E))) =
1993 ("access to specific tagged type required (RM 3.9.2(9))", E);
1996 -- (Ada 2005: AI-230): Accessibility check for anonymous
1999 if Type_Access_Level (Etype (E)) >
2000 Deepest_Type_Access_Level (T)
2003 ("expression has deeper access level than component " &
2004 "(RM 3.10.2 (12.2))", E);
2007 -- The initialization expression is a reference to an access
2008 -- discriminant. The type of the discriminant is always deeper
2009 -- than any access type.
2011 if Ekind (Etype (E)) = E_Anonymous_Access_Type
2012 and then Is_Entity_Name (E)
2013 and then Ekind (Entity (E)) = E_In_Parameter
2014 and then Present (Discriminal_Link (Entity (E)))
2017 ("discriminant has deeper accessibility level than target",
2023 -- The parent type may be a private view with unknown discriminants,
2024 -- and thus unconstrained. Regular components must be constrained.
2026 if not Is_Definite_Subtype (T) and then Chars (Id) /= Name_uParent then
2027 if Is_Class_Wide_Type (T) then
2029 ("class-wide subtype with unknown discriminants" &
2030 " in component declaration",
2031 Subtype_Indication (Component_Definition (N)));
2034 ("unconstrained subtype in component declaration",
2035 Subtype_Indication (Component_Definition (N)));
2038 -- Components cannot be abstract, except for the special case of
2039 -- the _Parent field (case of extending an abstract tagged type)
2041 elsif Is_Abstract_Type (T) and then Chars (Id) /= Name_uParent then
2042 Error_Msg_N ("type of a component cannot be abstract", N);
2046 Set_Is_Aliased (Id, Aliased_Present (Component_Definition (N)));
2048 -- The component declaration may have a per-object constraint, set
2049 -- the appropriate flag in the defining identifier of the subtype.
2051 if Present (Subtype_Indication (Component_Definition (N))) then
2053 Sindic : constant Node_Id :=
2054 Subtype_Indication (Component_Definition (N));
2056 if Nkind (Sindic) = N_Subtype_Indication
2057 and then Present (Constraint (Sindic))
2058 and then Contains_POC (Constraint (Sindic))
2060 Set_Has_Per_Object_Constraint (Id);
2065 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
2066 -- out some static checks.
2068 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
2069 Null_Exclusion_Static_Checks (N);
2072 -- If this component is private (or depends on a private type), flag the
2073 -- record type to indicate that some operations are not available.
2075 P := Private_Component (T);
2079 -- Check for circular definitions
2081 if P = Any_Type then
2082 Set_Etype (Id, Any_Type);
2084 -- There is a gap in the visibility of operations only if the
2085 -- component type is not defined in the scope of the record type.
2087 elsif Scope (P) = Scope (Current_Scope) then
2090 elsif Is_Limited_Type (P) then
2091 Set_Is_Limited_Composite (Current_Scope);
2094 Set_Is_Private_Composite (Current_Scope);
2099 and then Is_Limited_Type (T)
2100 and then Chars (Id) /= Name_uParent
2101 and then Is_Tagged_Type (Current_Scope)
2103 if Is_Derived_Type (Current_Scope)
2104 and then not Is_Known_Limited (Current_Scope)
2107 ("extension of nonlimited type cannot have limited components",
2110 if Is_Interface (Root_Type (Current_Scope)) then
2112 ("\limitedness is not inherited from limited interface", N);
2113 Error_Msg_N ("\add LIMITED to type indication", N);
2116 Explain_Limited_Type (T, N);
2117 Set_Etype (Id, Any_Type);
2118 Set_Is_Limited_Composite (Current_Scope, False);
2120 elsif not Is_Derived_Type (Current_Scope)
2121 and then not Is_Limited_Record (Current_Scope)
2122 and then not Is_Concurrent_Type (Current_Scope)
2125 ("nonlimited tagged type cannot have limited components", N);
2126 Explain_Limited_Type (T, N);
2127 Set_Etype (Id, Any_Type);
2128 Set_Is_Limited_Composite (Current_Scope, False);
2132 -- If the component is an unconstrained task or protected type with
2133 -- discriminants, the component and the enclosing record are limited
2134 -- and the component is constrained by its default values. Compute
2135 -- its actual subtype, else it may be allocated the maximum size by
2136 -- the backend, and possibly overflow.
2138 if Is_Concurrent_Type (T)
2139 and then not Is_Constrained (T)
2140 and then Has_Discriminants (T)
2141 and then not Has_Discriminants (Current_Scope)
2144 Act_T : constant Entity_Id := Build_Default_Subtype (T, N);
2147 Set_Etype (Id, Act_T);
2149 -- Rewrite component definition to use the constrained subtype
2151 Rewrite (Component_Definition (N),
2152 Make_Component_Definition (Loc,
2153 Subtype_Indication => New_Occurrence_Of (Act_T, Loc)));
2157 Set_Original_Record_Component (Id, Id);
2159 if Has_Aspects (N) then
2160 Analyze_Aspect_Specifications (N, Id);
2163 Analyze_Dimension (N);
2164 end Analyze_Component_Declaration;
2166 --------------------------
2167 -- Analyze_Declarations --
2168 --------------------------
2170 procedure Analyze_Declarations (L : List_Id) is
2173 procedure Adjust_Decl;
2174 -- Adjust Decl not to include implicit label declarations, since these
2175 -- have strange Sloc values that result in elaboration check problems.
2176 -- (They have the sloc of the label as found in the source, and that
2177 -- is ahead of the current declarative part).
2179 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id);
2180 -- Determine whether Body_Decl denotes the body of a late controlled
2181 -- primitive (either Initialize, Adjust or Finalize). If this is the
2182 -- case, add a proper spec if the body lacks one. The spec is inserted
2183 -- before Body_Decl and immedately analyzed.
2185 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id);
2186 -- Spec_Id is the entity of a package that may define abstract states.
2187 -- If the states have visible refinement, remove the visibility of each
2188 -- constituent at the end of the package body declarations.
2194 procedure Adjust_Decl is
2196 while Present (Prev (Decl))
2197 and then Nkind (Decl) = N_Implicit_Label_Declaration
2203 --------------------------------------
2204 -- Handle_Late_Controlled_Primitive --
2205 --------------------------------------
2207 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id) is
2208 Body_Spec : constant Node_Id := Specification (Body_Decl);
2209 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2210 Loc : constant Source_Ptr := Sloc (Body_Id);
2211 Params : constant List_Id :=
2212 Parameter_Specifications (Body_Spec);
2214 Spec_Id : Entity_Id;
2218 -- Consider only procedure bodies whose name matches one of the three
2219 -- controlled primitives.
2221 if Nkind (Body_Spec) /= N_Procedure_Specification
2222 or else not Nam_In (Chars (Body_Id), Name_Adjust,
2228 -- A controlled primitive must have exactly one formal which is not
2229 -- an anonymous access type.
2231 elsif List_Length (Params) /= 1 then
2235 Typ := Parameter_Type (First (Params));
2237 if Nkind (Typ) = N_Access_Definition then
2243 -- The type of the formal must be derived from [Limited_]Controlled
2245 if not Is_Controlled (Entity (Typ)) then
2249 -- Check whether a specification exists for this body. We do not
2250 -- analyze the spec of the body in full, because it will be analyzed
2251 -- again when the body is properly analyzed, and we cannot create
2252 -- duplicate entries in the formals chain. We look for an explicit
2253 -- specification because the body may be an overriding operation and
2254 -- an inherited spec may be present.
2256 Spec_Id := Current_Entity (Body_Id);
2258 while Present (Spec_Id) loop
2259 if Ekind_In (Spec_Id, E_Procedure, E_Generic_Procedure)
2260 and then Scope (Spec_Id) = Current_Scope
2261 and then Present (First_Formal (Spec_Id))
2262 and then No (Next_Formal (First_Formal (Spec_Id)))
2263 and then Etype (First_Formal (Spec_Id)) = Entity (Typ)
2264 and then Comes_From_Source (Spec_Id)
2269 Spec_Id := Homonym (Spec_Id);
2272 -- At this point the body is known to be a late controlled primitive.
2273 -- Generate a matching spec and insert it before the body. Note the
2274 -- use of Copy_Separate_Tree - we want an entirely separate semantic
2275 -- tree in this case.
2277 Spec := Copy_Separate_Tree (Body_Spec);
2279 -- Ensure that the subprogram declaration does not inherit the null
2280 -- indicator from the body as we now have a proper spec/body pair.
2282 Set_Null_Present (Spec, False);
2284 Insert_Before_And_Analyze (Body_Decl,
2285 Make_Subprogram_Declaration (Loc, Specification => Spec));
2286 end Handle_Late_Controlled_Primitive;
2288 --------------------------------
2289 -- Remove_Visible_Refinements --
2290 --------------------------------
2292 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id) is
2293 State_Elmt : Elmt_Id;
2295 if Present (Abstract_States (Spec_Id)) then
2296 State_Elmt := First_Elmt (Abstract_States (Spec_Id));
2297 while Present (State_Elmt) loop
2298 Set_Has_Visible_Refinement (Node (State_Elmt), False);
2299 Next_Elmt (State_Elmt);
2302 end Remove_Visible_Refinements;
2306 Context : Node_Id := Empty;
2307 Freeze_From : Entity_Id := Empty;
2308 Next_Decl : Node_Id;
2309 Pack_Decl : Node_Id := Empty;
2311 Body_Seen : Boolean := False;
2312 -- Flag set when the first body [stub] is encountered
2314 -- Start of processing for Analyze_Declarations
2317 if Restriction_Check_Required (SPARK_05) then
2318 Check_Later_Vs_Basic_Declarations (L, During_Parsing => False);
2322 while Present (Decl) loop
2324 -- Package spec cannot contain a package declaration in SPARK
2326 if Nkind (Decl) = N_Package_Declaration
2327 and then Nkind (Parent (L)) = N_Package_Specification
2329 Check_SPARK_05_Restriction
2330 ("package specification cannot contain a package declaration",
2334 -- Complete analysis of declaration
2337 Next_Decl := Next (Decl);
2339 if No (Freeze_From) then
2340 Freeze_From := First_Entity (Current_Scope);
2343 -- At the end of a declarative part, freeze remaining entities
2344 -- declared in it. The end of the visible declarations of package
2345 -- specification is not the end of a declarative part if private
2346 -- declarations are present. The end of a package declaration is a
2347 -- freezing point only if it a library package. A task definition or
2348 -- protected type definition is not a freeze point either. Finally,
2349 -- we do not freeze entities in generic scopes, because there is no
2350 -- code generated for them and freeze nodes will be generated for
2353 -- The end of a package instantiation is not a freeze point, but
2354 -- for now we make it one, because the generic body is inserted
2355 -- (currently) immediately after. Generic instantiations will not
2356 -- be a freeze point once delayed freezing of bodies is implemented.
2357 -- (This is needed in any case for early instantiations ???).
2359 if No (Next_Decl) then
2360 if Nkind_In (Parent (L), N_Component_List,
2362 N_Protected_Definition)
2366 elsif Nkind (Parent (L)) /= N_Package_Specification then
2367 if Nkind (Parent (L)) = N_Package_Body then
2368 Freeze_From := First_Entity (Current_Scope);
2371 -- There may have been several freezing points previously,
2372 -- for example object declarations or subprogram bodies, but
2373 -- at the end of a declarative part we check freezing from
2374 -- the beginning, even though entities may already be frozen,
2375 -- in order to perform visibility checks on delayed aspects.
2378 Freeze_All (First_Entity (Current_Scope), Decl);
2379 Freeze_From := Last_Entity (Current_Scope);
2381 elsif Scope (Current_Scope) /= Standard_Standard
2382 and then not Is_Child_Unit (Current_Scope)
2383 and then No (Generic_Parent (Parent (L)))
2387 elsif L /= Visible_Declarations (Parent (L))
2388 or else No (Private_Declarations (Parent (L)))
2389 or else Is_Empty_List (Private_Declarations (Parent (L)))
2392 Freeze_All (First_Entity (Current_Scope), Decl);
2393 Freeze_From := Last_Entity (Current_Scope);
2396 -- If next node is a body then freeze all types before the body.
2397 -- An exception occurs for some expander-generated bodies. If these
2398 -- are generated at places where in general language rules would not
2399 -- allow a freeze point, then we assume that the expander has
2400 -- explicitly checked that all required types are properly frozen,
2401 -- and we do not cause general freezing here. This special circuit
2402 -- is used when the encountered body is marked as having already
2405 -- In all other cases (bodies that come from source, and expander
2406 -- generated bodies that have not been analyzed yet), freeze all
2407 -- types now. Note that in the latter case, the expander must take
2408 -- care to attach the bodies at a proper place in the tree so as to
2409 -- not cause unwanted freezing at that point.
2411 elsif not Analyzed (Next_Decl) and then Is_Body (Next_Decl) then
2413 -- When a controlled type is frozen, the expander generates stream
2414 -- and controlled type support routines. If the freeze is caused
2415 -- by the stand alone body of Initialize, Adjust and Finalize, the
2416 -- expander will end up using the wrong version of these routines
2417 -- as the body has not been processed yet. To remedy this, detect
2418 -- a late controlled primitive and create a proper spec for it.
2419 -- This ensures that the primitive will override its inherited
2420 -- counterpart before the freeze takes place.
2422 -- If the declaration we just processed is a body, do not attempt
2423 -- to examine Next_Decl as the late primitive idiom can only apply
2424 -- to the first encountered body.
2426 -- The spec of the late primitive is not generated in ASIS mode to
2427 -- ensure a consistent list of primitives that indicates the true
2428 -- semantic structure of the program (which is not relevant when
2429 -- generating executable code.
2431 -- ??? a cleaner approach may be possible and/or this solution
2432 -- could be extended to general-purpose late primitives, TBD.
2434 if not ASIS_Mode and then not Body_Seen and then not Is_Body (Decl)
2438 if Nkind (Next_Decl) = N_Subprogram_Body then
2439 Handle_Late_Controlled_Primitive (Next_Decl);
2444 Freeze_All (Freeze_From, Decl);
2445 Freeze_From := Last_Entity (Current_Scope);
2451 -- Analyze the contracts of packages and their bodies
2454 Context := Parent (L);
2456 if Nkind (Context) = N_Package_Specification then
2457 Pack_Decl := Parent (Context);
2459 -- When a package has private declarations, its contract must be
2460 -- analyzed at the end of the said declarations. This way both the
2461 -- analysis and freeze actions are properly synchronized in case
2462 -- of private type use within the contract.
2464 if L = Private_Declarations (Context) then
2465 Analyze_Package_Contract (Defining_Entity (Context));
2467 -- Build the bodies of the default initial condition procedures
2468 -- for all types subject to pragma Default_Initial_Condition.
2469 -- From a purely Ada stand point, this is a freezing activity,
2470 -- however freezing is not available under GNATprove_Mode. To
2471 -- accomodate both scenarios, the bodies are build at the end
2472 -- of private declaration analysis.
2474 Build_Default_Init_Cond_Procedure_Bodies (L);
2476 -- Otherwise the contract is analyzed at the end of the visible
2479 elsif L = Visible_Declarations (Context)
2480 and then No (Private_Declarations (Context))
2482 Analyze_Package_Contract (Defining_Entity (Context));
2485 elsif Nkind (Context) = N_Package_Body then
2486 Pack_Decl := Context;
2487 Analyze_Package_Body_Contract (Defining_Entity (Context));
2490 -- Analyze the contracts of all subprogram declarations, subprogram
2491 -- bodies and variables now due to the delayed visibility needs of
2492 -- of their aspects and pragmas. Capture global references in generic
2493 -- subprograms or bodies.
2496 while Present (Decl) loop
2497 if Nkind (Decl) = N_Object_Declaration then
2498 Analyze_Object_Contract (Defining_Entity (Decl));
2500 elsif Nkind_In (Decl, N_Abstract_Subprogram_Declaration,
2501 N_Generic_Subprogram_Declaration,
2502 N_Subprogram_Declaration)
2504 Analyze_Subprogram_Contract (Defining_Entity (Decl));
2506 elsif Nkind (Decl) = N_Subprogram_Body then
2507 Analyze_Subprogram_Body_Contract (Defining_Entity (Decl));
2509 elsif Nkind (Decl) = N_Subprogram_Body_Stub then
2510 Analyze_Subprogram_Body_Stub_Contract (Defining_Entity (Decl));
2513 -- Capture all global references in a generic subprogram or a body
2514 -- [stub] now that the contract has been analyzed.
2516 if Nkind_In (Decl, N_Generic_Subprogram_Declaration,
2518 N_Subprogram_Body_Stub)
2519 and then Is_Generic_Declaration_Or_Body (Decl)
2521 Save_Global_References_In_Contract
2522 (Templ => Original_Node (Decl),
2523 Gen_Id => Corresponding_Spec_Of (Decl));
2529 -- The owner of the declarations is a package [body]
2531 if Present (Pack_Decl) then
2533 -- Capture all global references in a generic package or a body
2534 -- after all nested generic subprograms and bodies were subjected
2535 -- to the same processing.
2537 if Is_Generic_Declaration_Or_Body (Pack_Decl) then
2538 Save_Global_References_In_Contract
2539 (Templ => Original_Node (Pack_Decl),
2540 Gen_Id => Corresponding_Spec_Of (Pack_Decl));
2543 -- State refinements are visible upto the end the of the package
2544 -- body declarations. Hide the state refinements from visibility
2545 -- to restore the original state conditions.
2547 if Nkind (Pack_Decl) = N_Package_Body then
2548 Remove_Visible_Refinements (Corresponding_Spec (Pack_Decl));
2552 end Analyze_Declarations;
2554 -----------------------------------
2555 -- Analyze_Full_Type_Declaration --
2556 -----------------------------------
2558 procedure Analyze_Full_Type_Declaration (N : Node_Id) is
2559 Def : constant Node_Id := Type_Definition (N);
2560 Def_Id : constant Entity_Id := Defining_Identifier (N);
2564 Is_Remote : constant Boolean :=
2565 (Is_Remote_Types (Current_Scope)
2566 or else Is_Remote_Call_Interface (Current_Scope))
2567 and then not (In_Private_Part (Current_Scope)
2568 or else In_Package_Body (Current_Scope));
2570 procedure Check_Nonoverridable_Aspects;
2571 -- Apply the rule in RM 13.1.1(18.4/4) on iterator aspects that cannot
2572 -- be overridden, and can only be confirmed on derivation.
2574 procedure Check_Ops_From_Incomplete_Type;
2575 -- If there is a tagged incomplete partial view of the type, traverse
2576 -- the primitives of the incomplete view and change the type of any
2577 -- controlling formals and result to indicate the full view. The
2578 -- primitives will be added to the full type's primitive operations
2579 -- list later in Sem_Disp.Check_Operation_From_Incomplete_Type (which
2580 -- is called from Process_Incomplete_Dependents).
2582 ----------------------------------
2583 -- Check_Nonoverridable_Aspects --
2584 ----------------------------------
2586 procedure Check_Nonoverridable_Aspects is
2587 Prev_Aspects : constant List_Id :=
2588 Aspect_Specifications (Parent (Def_Id));
2589 Par_Type : Entity_Id;
2591 function Has_Aspect_Spec
2593 Aspect_Name : Name_Id) return Boolean;
2594 -- Check whether a list of aspect specifications includes an entry
2595 -- for a specific aspect. The list is either that of a partial or
2598 ---------------------
2599 -- Has_Aspect_Spec --
2600 ---------------------
2602 function Has_Aspect_Spec
2604 Aspect_Name : Name_Id) return Boolean
2608 Spec := First (Specs);
2609 while Present (Spec) loop
2610 if Chars (Identifier (Spec)) = Aspect_Name then
2616 end Has_Aspect_Spec;
2618 -- Start of processing for Check_Nonoverridable_Aspects
2622 -- Get parent type of derived type. Note that Prev is the entity
2623 -- in the partial declaration, but its contents are now those of
2624 -- full view, while Def_Id reflects the partial view.
2626 if Is_Private_Type (Def_Id) then
2627 Par_Type := Etype (Full_View (Def_Id));
2629 Par_Type := Etype (Def_Id);
2632 -- If there is an inherited Implicit_Dereference, verify that it is
2633 -- made explicit in the partial view.
2635 if Has_Discriminants (Base_Type (Par_Type))
2636 and then Nkind (Parent (Prev)) = N_Full_Type_Declaration
2637 and then Present (Discriminant_Specifications (Parent (Prev)))
2638 and then Present (Get_Reference_Discriminant (Par_Type))
2641 not Has_Aspect_Spec (Prev_Aspects, Name_Implicit_Dereference)
2644 ("type does not inherit implicit dereference", Prev);
2647 -- If one of the views has the aspect specified, verify that it
2648 -- is consistent with that of the parent.
2651 Par_Discr : constant Entity_Id :=
2652 Get_Reference_Discriminant (Par_Type);
2653 Cur_Discr : constant Entity_Id :=
2654 Get_Reference_Discriminant (Prev);
2656 if Corresponding_Discriminant (Cur_Discr) /= Par_Discr then
2657 Error_Msg_N ("aspect incosistent with that of parent", N);
2663 -- TBD : other nonoverridable aspects.
2664 end Check_Nonoverridable_Aspects;
2666 ------------------------------------
2667 -- Check_Ops_From_Incomplete_Type --
2668 ------------------------------------
2670 procedure Check_Ops_From_Incomplete_Type is
2677 and then Ekind (Prev) = E_Incomplete_Type
2678 and then Is_Tagged_Type (Prev)
2679 and then Is_Tagged_Type (T)
2681 Elmt := First_Elmt (Primitive_Operations (Prev));
2682 while Present (Elmt) loop
2685 Formal := First_Formal (Op);
2686 while Present (Formal) loop
2687 if Etype (Formal) = Prev then
2688 Set_Etype (Formal, T);
2691 Next_Formal (Formal);
2694 if Etype (Op) = Prev then
2701 end Check_Ops_From_Incomplete_Type;
2703 -- Start of processing for Analyze_Full_Type_Declaration
2706 Prev := Find_Type_Name (N);
2708 -- The full view, if present, now points to the current type. If there
2709 -- is an incomplete partial view, set a link to it, to simplify the
2710 -- retrieval of primitive operations of the type.
2712 -- Ada 2005 (AI-50217): If the type was previously decorated when
2713 -- imported through a LIMITED WITH clause, it appears as incomplete
2714 -- but has no full view.
2716 if Ekind (Prev) = E_Incomplete_Type
2717 and then Present (Full_View (Prev))
2719 T := Full_View (Prev);
2720 Set_Incomplete_View (N, Parent (Prev));
2725 Set_Is_Pure (T, Is_Pure (Current_Scope));
2727 -- We set the flag Is_First_Subtype here. It is needed to set the
2728 -- corresponding flag for the Implicit class-wide-type created
2729 -- during tagged types processing.
2731 Set_Is_First_Subtype (T, True);
2733 -- Only composite types other than array types are allowed to have
2738 -- For derived types, the rule will be checked once we've figured
2739 -- out the parent type.
2741 when N_Derived_Type_Definition =>
2744 -- For record types, discriminants are allowed, unless we are in
2747 when N_Record_Definition =>
2748 if Present (Discriminant_Specifications (N)) then
2749 Check_SPARK_05_Restriction
2750 ("discriminant type is not allowed",
2752 (First (Discriminant_Specifications (N))));
2756 if Present (Discriminant_Specifications (N)) then
2758 ("elementary or array type cannot have discriminants",
2760 (First (Discriminant_Specifications (N))));
2764 -- Elaborate the type definition according to kind, and generate
2765 -- subsidiary (implicit) subtypes where needed. We skip this if it was
2766 -- already done (this happens during the reanalysis that follows a call
2767 -- to the high level optimizer).
2769 if not Analyzed (T) then
2773 when N_Access_To_Subprogram_Definition =>
2774 Access_Subprogram_Declaration (T, Def);
2776 -- If this is a remote access to subprogram, we must create the
2777 -- equivalent fat pointer type, and related subprograms.
2780 Process_Remote_AST_Declaration (N);
2783 -- Validate categorization rule against access type declaration
2784 -- usually a violation in Pure unit, Shared_Passive unit.
2786 Validate_Access_Type_Declaration (T, N);
2788 when N_Access_To_Object_Definition =>
2789 Access_Type_Declaration (T, Def);
2791 -- Validate categorization rule against access type declaration
2792 -- usually a violation in Pure unit, Shared_Passive unit.
2794 Validate_Access_Type_Declaration (T, N);
2796 -- If we are in a Remote_Call_Interface package and define a
2797 -- RACW, then calling stubs and specific stream attributes
2801 and then Is_Remote_Access_To_Class_Wide_Type (Def_Id)
2803 Add_RACW_Features (Def_Id);
2806 when N_Array_Type_Definition =>
2807 Array_Type_Declaration (T, Def);
2809 when N_Derived_Type_Definition =>
2810 Derived_Type_Declaration (T, N, T /= Def_Id);
2812 when N_Enumeration_Type_Definition =>
2813 Enumeration_Type_Declaration (T, Def);
2815 when N_Floating_Point_Definition =>
2816 Floating_Point_Type_Declaration (T, Def);
2818 when N_Decimal_Fixed_Point_Definition =>
2819 Decimal_Fixed_Point_Type_Declaration (T, Def);
2821 when N_Ordinary_Fixed_Point_Definition =>
2822 Ordinary_Fixed_Point_Type_Declaration (T, Def);
2824 when N_Signed_Integer_Type_Definition =>
2825 Signed_Integer_Type_Declaration (T, Def);
2827 when N_Modular_Type_Definition =>
2828 Modular_Type_Declaration (T, Def);
2830 when N_Record_Definition =>
2831 Record_Type_Declaration (T, N, Prev);
2833 -- If declaration has a parse error, nothing to elaborate.
2839 raise Program_Error;
2844 if Etype (T) = Any_Type then
2848 -- Controlled type is not allowed in SPARK
2850 if Is_Visibly_Controlled (T) then
2851 Check_SPARK_05_Restriction ("controlled type is not allowed", N);
2854 -- A type declared within a Ghost region is automatically Ghost
2855 -- (SPARK RM 6.9(2)).
2857 if Ghost_Mode > None then
2858 Set_Is_Ghost_Entity (T);
2861 -- Some common processing for all types
2863 Set_Depends_On_Private (T, Has_Private_Component (T));
2864 Check_Ops_From_Incomplete_Type;
2866 -- Both the declared entity, and its anonymous base type if one was
2867 -- created, need freeze nodes allocated.
2870 B : constant Entity_Id := Base_Type (T);
2873 -- In the case where the base type differs from the first subtype, we
2874 -- pre-allocate a freeze node, and set the proper link to the first
2875 -- subtype. Freeze_Entity will use this preallocated freeze node when
2876 -- it freezes the entity.
2878 -- This does not apply if the base type is a generic type, whose
2879 -- declaration is independent of the current derived definition.
2881 if B /= T and then not Is_Generic_Type (B) then
2882 Ensure_Freeze_Node (B);
2883 Set_First_Subtype_Link (Freeze_Node (B), T);
2886 -- A type that is imported through a limited_with clause cannot
2887 -- generate any code, and thus need not be frozen. However, an access
2888 -- type with an imported designated type needs a finalization list,
2889 -- which may be referenced in some other package that has non-limited
2890 -- visibility on the designated type. Thus we must create the
2891 -- finalization list at the point the access type is frozen, to
2892 -- prevent unsatisfied references at link time.
2894 if not From_Limited_With (T) or else Is_Access_Type (T) then
2895 Set_Has_Delayed_Freeze (T);
2899 -- Case where T is the full declaration of some private type which has
2900 -- been swapped in Defining_Identifier (N).
2902 if T /= Def_Id and then Is_Private_Type (Def_Id) then
2903 Process_Full_View (N, T, Def_Id);
2905 -- Record the reference. The form of this is a little strange, since
2906 -- the full declaration has been swapped in. So the first parameter
2907 -- here represents the entity to which a reference is made which is
2908 -- the "real" entity, i.e. the one swapped in, and the second
2909 -- parameter provides the reference location.
2911 -- Also, we want to kill Has_Pragma_Unreferenced temporarily here
2912 -- since we don't want a complaint about the full type being an
2913 -- unwanted reference to the private type
2916 B : constant Boolean := Has_Pragma_Unreferenced (T);
2918 Set_Has_Pragma_Unreferenced (T, False);
2919 Generate_Reference (T, T, 'c');
2920 Set_Has_Pragma_Unreferenced (T, B);
2923 Set_Completion_Referenced (Def_Id);
2925 -- For completion of incomplete type, process incomplete dependents
2926 -- and always mark the full type as referenced (it is the incomplete
2927 -- type that we get for any real reference).
2929 elsif Ekind (Prev) = E_Incomplete_Type then
2930 Process_Incomplete_Dependents (N, T, Prev);
2931 Generate_Reference (Prev, Def_Id, 'c');
2932 Set_Completion_Referenced (Def_Id);
2934 -- If not private type or incomplete type completion, this is a real
2935 -- definition of a new entity, so record it.
2938 Generate_Definition (Def_Id);
2941 -- Propagate any pending access types whose finalization masters need to
2942 -- be fully initialized from the partial to the full view. Guard against
2943 -- an illegal full view that remains unanalyzed.
2945 if Is_Type (Def_Id) and then Is_Incomplete_Or_Private_Type (Prev) then
2946 Set_Pending_Access_Types (Def_Id, Pending_Access_Types (Prev));
2949 if Chars (Scope (Def_Id)) = Name_System
2950 and then Chars (Def_Id) = Name_Address
2951 and then Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (N)))
2953 Set_Is_Descendent_Of_Address (Def_Id);
2954 Set_Is_Descendent_Of_Address (Base_Type (Def_Id));
2955 Set_Is_Descendent_Of_Address (Prev);
2958 Set_Optimize_Alignment_Flags (Def_Id);
2959 Check_Eliminated (Def_Id);
2961 -- If the declaration is a completion and aspects are present, apply
2962 -- them to the entity for the type which is currently the partial
2963 -- view, but which is the one that will be frozen.
2965 if Has_Aspects (N) then
2967 -- In most cases the partial view is a private type, and both views
2968 -- appear in different declarative parts. In the unusual case where
2969 -- the partial view is incomplete, perform the analysis on the
2970 -- full view, to prevent freezing anomalies with the corresponding
2971 -- class-wide type, which otherwise might be frozen before the
2972 -- dispatch table is built.
2975 and then Ekind (Prev) /= E_Incomplete_Type
2977 Analyze_Aspect_Specifications (N, Prev);
2982 Analyze_Aspect_Specifications (N, Def_Id);
2986 if Is_Derived_Type (Prev)
2987 and then Def_Id /= Prev
2989 Check_Nonoverridable_Aspects;
2991 end Analyze_Full_Type_Declaration;
2993 ----------------------------------
2994 -- Analyze_Incomplete_Type_Decl --
2995 ----------------------------------
2997 procedure Analyze_Incomplete_Type_Decl (N : Node_Id) is
2998 F : constant Boolean := Is_Pure (Current_Scope);
3002 Check_SPARK_05_Restriction ("incomplete type is not allowed", N);
3004 Generate_Definition (Defining_Identifier (N));
3006 -- Process an incomplete declaration. The identifier must not have been
3007 -- declared already in the scope. However, an incomplete declaration may
3008 -- appear in the private part of a package, for a private type that has
3009 -- already been declared.
3011 -- In this case, the discriminants (if any) must match
3013 T := Find_Type_Name (N);
3015 Set_Ekind (T, E_Incomplete_Type);
3016 Init_Size_Align (T);
3017 Set_Is_First_Subtype (T, True);
3020 -- An incomplete type declared within a Ghost region is automatically
3021 -- Ghost (SPARK RM 6.9(2)).
3023 if Ghost_Mode > None then
3024 Set_Is_Ghost_Entity (T);
3027 -- Ada 2005 (AI-326): Minimum decoration to give support to tagged
3028 -- incomplete types.
3030 if Tagged_Present (N) then
3031 Set_Is_Tagged_Type (T, True);
3032 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
3033 Make_Class_Wide_Type (T);
3034 Set_Direct_Primitive_Operations (T, New_Elmt_List);
3039 Set_Stored_Constraint (T, No_Elist);
3041 if Present (Discriminant_Specifications (N)) then
3042 Process_Discriminants (N);
3047 -- If the type has discriminants, non-trivial subtypes may be
3048 -- declared before the full view of the type. The full views of those
3049 -- subtypes will be built after the full view of the type.
3051 Set_Private_Dependents (T, New_Elmt_List);
3053 end Analyze_Incomplete_Type_Decl;
3055 -----------------------------------
3056 -- Analyze_Interface_Declaration --
3057 -----------------------------------
3059 procedure Analyze_Interface_Declaration (T : Entity_Id; Def : Node_Id) is
3060 CW : constant Entity_Id := Class_Wide_Type (T);
3063 Set_Is_Tagged_Type (T);
3064 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
3066 Set_Is_Limited_Record (T, Limited_Present (Def)
3067 or else Task_Present (Def)
3068 or else Protected_Present (Def)
3069 or else Synchronized_Present (Def));
3071 -- Type is abstract if full declaration carries keyword, or if previous
3072 -- partial view did.
3074 Set_Is_Abstract_Type (T);
3075 Set_Is_Interface (T);
3077 -- Type is a limited interface if it includes the keyword limited, task,
3078 -- protected, or synchronized.
3080 Set_Is_Limited_Interface
3081 (T, Limited_Present (Def)
3082 or else Protected_Present (Def)
3083 or else Synchronized_Present (Def)
3084 or else Task_Present (Def));
3086 Set_Interfaces (T, New_Elmt_List);
3087 Set_Direct_Primitive_Operations (T, New_Elmt_List);
3089 -- Complete the decoration of the class-wide entity if it was already
3090 -- built (i.e. during the creation of the limited view)
3092 if Present (CW) then
3093 Set_Is_Interface (CW);
3094 Set_Is_Limited_Interface (CW, Is_Limited_Interface (T));
3097 -- Check runtime support for synchronized interfaces
3099 if (Is_Task_Interface (T)
3100 or else Is_Protected_Interface (T)
3101 or else Is_Synchronized_Interface (T))
3102 and then not RTE_Available (RE_Select_Specific_Data)
3104 Error_Msg_CRT ("synchronized interfaces", T);
3106 end Analyze_Interface_Declaration;
3108 -----------------------------
3109 -- Analyze_Itype_Reference --
3110 -----------------------------
3112 -- Nothing to do. This node is placed in the tree only for the benefit of
3113 -- back end processing, and has no effect on the semantic processing.
3115 procedure Analyze_Itype_Reference (N : Node_Id) is
3117 pragma Assert (Is_Itype (Itype (N)));
3119 end Analyze_Itype_Reference;
3121 --------------------------------
3122 -- Analyze_Number_Declaration --
3123 --------------------------------
3125 procedure Analyze_Number_Declaration (N : Node_Id) is
3126 E : constant Node_Id := Expression (N);
3127 Id : constant Entity_Id := Defining_Identifier (N);
3128 Index : Interp_Index;
3133 Generate_Definition (Id);
3136 -- A number declared within a Ghost region is automatically Ghost
3137 -- (SPARK RM 6.9(2)).
3139 if Ghost_Mode > None then
3140 Set_Is_Ghost_Entity (Id);
3143 -- This is an optimization of a common case of an integer literal
3145 if Nkind (E) = N_Integer_Literal then
3146 Set_Is_Static_Expression (E, True);
3147 Set_Etype (E, Universal_Integer);
3149 Set_Etype (Id, Universal_Integer);
3150 Set_Ekind (Id, E_Named_Integer);
3151 Set_Is_Frozen (Id, True);
3155 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3157 -- Process expression, replacing error by integer zero, to avoid
3158 -- cascaded errors or aborts further along in the processing
3160 -- Replace Error by integer zero, which seems least likely to cause
3164 Rewrite (E, Make_Integer_Literal (Sloc (E), Uint_0));
3165 Set_Error_Posted (E);
3170 -- Verify that the expression is static and numeric. If
3171 -- the expression is overloaded, we apply the preference
3172 -- rule that favors root numeric types.
3174 if not Is_Overloaded (E) then
3176 if Has_Dynamic_Predicate_Aspect (T) then
3178 ("subtype has dynamic predicate, "
3179 & "not allowed in number declaration", N);
3185 Get_First_Interp (E, Index, It);
3186 while Present (It.Typ) loop
3187 if (Is_Integer_Type (It.Typ) or else Is_Real_Type (It.Typ))
3188 and then (Scope (Base_Type (It.Typ))) = Standard_Standard
3190 if T = Any_Type then
3193 elsif It.Typ = Universal_Real
3195 It.Typ = Universal_Integer
3197 -- Choose universal interpretation over any other
3204 Get_Next_Interp (Index, It);
3208 if Is_Integer_Type (T) then
3210 Set_Etype (Id, Universal_Integer);
3211 Set_Ekind (Id, E_Named_Integer);
3213 elsif Is_Real_Type (T) then
3215 -- Because the real value is converted to universal_real, this is a
3216 -- legal context for a universal fixed expression.
3218 if T = Universal_Fixed then
3220 Loc : constant Source_Ptr := Sloc (N);
3221 Conv : constant Node_Id := Make_Type_Conversion (Loc,
3223 New_Occurrence_Of (Universal_Real, Loc),
3224 Expression => Relocate_Node (E));
3231 elsif T = Any_Fixed then
3232 Error_Msg_N ("illegal context for mixed mode operation", E);
3234 -- Expression is of the form : universal_fixed * integer. Try to
3235 -- resolve as universal_real.
3237 T := Universal_Real;
3242 Set_Etype (Id, Universal_Real);
3243 Set_Ekind (Id, E_Named_Real);
3246 Wrong_Type (E, Any_Numeric);
3250 Set_Ekind (Id, E_Constant);
3251 Set_Never_Set_In_Source (Id, True);
3252 Set_Is_True_Constant (Id, True);
3256 if Nkind_In (E, N_Integer_Literal, N_Real_Literal) then
3257 Set_Etype (E, Etype (Id));
3260 if not Is_OK_Static_Expression (E) then
3261 Flag_Non_Static_Expr
3262 ("non-static expression used in number declaration!", E);
3263 Rewrite (E, Make_Integer_Literal (Sloc (N), 1));
3264 Set_Etype (E, Any_Type);
3266 end Analyze_Number_Declaration;
3268 -----------------------------
3269 -- Analyze_Object_Contract --
3270 -----------------------------
3272 procedure Analyze_Object_Contract (Obj_Id : Entity_Id) is
3273 Obj_Typ : constant Entity_Id := Etype (Obj_Id);
3274 AR_Val : Boolean := False;
3275 AW_Val : Boolean := False;
3276 ER_Val : Boolean := False;
3277 EW_Val : Boolean := False;
3279 Seen : Boolean := False;
3282 -- The loop parameter in an element iterator over a formal container
3283 -- is declared with an object declaration but no contracts apply.
3285 if Ekind (Obj_Id) = E_Loop_Parameter then
3289 -- Constant related checks
3291 if Ekind (Obj_Id) = E_Constant then
3293 -- A constant cannot be effectively volatile. This check is only
3294 -- relevant with SPARK_Mode on as it is not a standard Ada legality
3295 -- rule. Do not flag internally-generated constants that map generic
3296 -- formals to actuals in instantiations (SPARK RM 7.1.3(6)).
3299 and then Is_Effectively_Volatile (Obj_Id)
3300 and then No (Corresponding_Generic_Association (Parent (Obj_Id)))
3302 -- Don't give this for internally generated entities (such as the
3303 -- FIRST and LAST temporaries generated for bounds).
3305 and then Comes_From_Source (Obj_Id)
3307 Error_Msg_N ("constant cannot be volatile", Obj_Id);
3310 -- Variable related checks
3312 else pragma Assert (Ekind (Obj_Id) = E_Variable);
3314 -- The following checks are only relevant when SPARK_Mode is on as
3315 -- they are not standard Ada legality rules. Internally generated
3316 -- temporaries are ignored.
3318 if SPARK_Mode = On and then Comes_From_Source (Obj_Id) then
3319 if Is_Effectively_Volatile (Obj_Id) then
3321 -- The declaration of an effectively volatile object must
3322 -- appear at the library level (SPARK RM 7.1.3(7), C.6(6)).
3324 if not Is_Library_Level_Entity (Obj_Id) then
3326 ("volatile variable & must be declared at library level",
3329 -- An object of a discriminated type cannot be effectively
3330 -- volatile (SPARK RM C.6(4)).
3332 elsif Has_Discriminants (Obj_Typ) then
3334 ("discriminated object & cannot be volatile", Obj_Id);
3336 -- An object of a tagged type cannot be effectively volatile
3337 -- (SPARK RM C.6(5)).
3339 elsif Is_Tagged_Type (Obj_Typ) then
3340 Error_Msg_N ("tagged object & cannot be volatile", Obj_Id);
3343 -- The object is not effectively volatile
3346 -- A non-effectively volatile object cannot have effectively
3347 -- volatile components (SPARK RM 7.1.3(7)).
3349 if not Is_Effectively_Volatile (Obj_Id)
3350 and then Has_Volatile_Component (Obj_Typ)
3353 ("non-volatile object & cannot have volatile components",
3359 if Is_Ghost_Entity (Obj_Id) then
3361 -- A Ghost object cannot be effectively volatile (SPARK RM 6.9(8))
3363 if Is_Effectively_Volatile (Obj_Id) then
3364 Error_Msg_N ("ghost variable & cannot be volatile", Obj_Id);
3366 -- A Ghost object cannot be imported or exported (SPARK RM 6.9(8))
3368 elsif Is_Imported (Obj_Id) then
3369 Error_Msg_N ("ghost object & cannot be imported", Obj_Id);
3371 elsif Is_Exported (Obj_Id) then
3372 Error_Msg_N ("ghost object & cannot be exported", Obj_Id);
3376 -- Analyze all external properties
3378 Prag := Get_Pragma (Obj_Id, Pragma_Async_Readers);
3380 if Present (Prag) then
3381 Analyze_External_Property_In_Decl_Part (Prag, AR_Val);
3385 Prag := Get_Pragma (Obj_Id, Pragma_Async_Writers);
3387 if Present (Prag) then
3388 Analyze_External_Property_In_Decl_Part (Prag, AW_Val);
3392 Prag := Get_Pragma (Obj_Id, Pragma_Effective_Reads);
3394 if Present (Prag) then
3395 Analyze_External_Property_In_Decl_Part (Prag, ER_Val);
3399 Prag := Get_Pragma (Obj_Id, Pragma_Effective_Writes);
3401 if Present (Prag) then
3402 Analyze_External_Property_In_Decl_Part (Prag, EW_Val);
3406 -- Verify the mutual interaction of the various external properties
3409 Check_External_Properties (Obj_Id, AR_Val, AW_Val, ER_Val, EW_Val);
3413 -- Check whether the lack of indicator Part_Of agrees with the placement
3414 -- of the object with respect to the state space.
3416 Prag := Get_Pragma (Obj_Id, Pragma_Part_Of);
3419 Check_Missing_Part_Of (Obj_Id);
3422 -- A ghost object cannot be imported or exported (SPARK RM 6.9(8))
3424 if Is_Ghost_Entity (Obj_Id) then
3425 if Is_Exported (Obj_Id) then
3426 Error_Msg_N ("ghost object & cannot be exported", Obj_Id);
3428 elsif Is_Imported (Obj_Id) then
3429 Error_Msg_N ("ghost object & cannot be imported", Obj_Id);
3432 end Analyze_Object_Contract;
3434 --------------------------------
3435 -- Analyze_Object_Declaration --
3436 --------------------------------
3438 procedure Analyze_Object_Declaration (N : Node_Id) is
3439 Loc : constant Source_Ptr := Sloc (N);
3440 Id : constant Entity_Id := Defining_Identifier (N);
3444 E : Node_Id := Expression (N);
3445 -- E is set to Expression (N) throughout this routine. When
3446 -- Expression (N) is modified, E is changed accordingly.
3448 Prev_Entity : Entity_Id := Empty;
3450 function Count_Tasks (T : Entity_Id) return Uint;
3451 -- This function is called when a non-generic library level object of a
3452 -- task type is declared. Its function is to count the static number of
3453 -- tasks declared within the type (it is only called if Has_Tasks is set
3454 -- for T). As a side effect, if an array of tasks with non-static bounds
3455 -- or a variant record type is encountered, Check_Restrictions is called
3456 -- indicating the count is unknown.
3458 function Delayed_Aspect_Present return Boolean;
3459 -- If the declaration has an expression that is an aggregate, and it
3460 -- has aspects that require delayed analysis, the resolution of the
3461 -- aggregate must be deferred to the freeze point of the objet. This
3462 -- special processing was created for address clauses, but it must
3463 -- also apply to Alignment. This must be done before the aspect
3464 -- specifications are analyzed because we must handle the aggregate
3465 -- before the analysis of the object declaration is complete.
3467 -- Any other relevant delayed aspects on object declarations ???
3473 function Count_Tasks (T : Entity_Id) return Uint is
3479 if Is_Task_Type (T) then
3482 elsif Is_Record_Type (T) then
3483 if Has_Discriminants (T) then
3484 Check_Restriction (Max_Tasks, N);
3489 C := First_Component (T);
3490 while Present (C) loop
3491 V := V + Count_Tasks (Etype (C));
3498 elsif Is_Array_Type (T) then
3499 X := First_Index (T);
3500 V := Count_Tasks (Component_Type (T));
3501 while Present (X) loop
3504 if not Is_OK_Static_Subtype (C) then
3505 Check_Restriction (Max_Tasks, N);
3508 V := V * (UI_Max (Uint_0,
3509 Expr_Value (Type_High_Bound (C)) -
3510 Expr_Value (Type_Low_Bound (C)) + Uint_1));
3523 ----------------------------
3524 -- Delayed_Aspect_Present --
3525 ----------------------------
3527 function Delayed_Aspect_Present return Boolean is
3532 if Present (Aspect_Specifications (N)) then
3533 A := First (Aspect_Specifications (N));
3534 A_Id := Get_Aspect_Id (Chars (Identifier (A)));
3535 while Present (A) loop
3536 if A_Id = Aspect_Alignment or else A_Id = Aspect_Address then
3545 end Delayed_Aspect_Present;
3549 Save_Ghost_Mode : constant Ghost_Mode_Type := Ghost_Mode;
3551 -- Start of processing for Analyze_Object_Declaration
3554 -- There are three kinds of implicit types generated by an
3555 -- object declaration:
3557 -- 1. Those generated by the original Object Definition
3559 -- 2. Those generated by the Expression
3561 -- 3. Those used to constrain the Object Definition with the
3562 -- expression constraints when the definition is unconstrained.
3564 -- They must be generated in this order to avoid order of elaboration
3565 -- issues. Thus the first step (after entering the name) is to analyze
3566 -- the object definition.
3568 if Constant_Present (N) then
3569 Prev_Entity := Current_Entity_In_Scope (Id);
3571 if Present (Prev_Entity)
3573 -- If the homograph is an implicit subprogram, it is overridden
3574 -- by the current declaration.
3576 ((Is_Overloadable (Prev_Entity)
3577 and then Is_Inherited_Operation (Prev_Entity))
3579 -- The current object is a discriminal generated for an entry
3580 -- family index. Even though the index is a constant, in this
3581 -- particular context there is no true constant redeclaration.
3582 -- Enter_Name will handle the visibility.
3585 (Is_Discriminal (Id)
3586 and then Ekind (Discriminal_Link (Id)) =
3587 E_Entry_Index_Parameter)
3589 -- The current object is the renaming for a generic declared
3590 -- within the instance.
3593 (Ekind (Prev_Entity) = E_Package
3594 and then Nkind (Parent (Prev_Entity)) =
3595 N_Package_Renaming_Declaration
3596 and then not Comes_From_Source (Prev_Entity)
3598 Is_Generic_Instance (Renamed_Entity (Prev_Entity))))
3600 Prev_Entity := Empty;
3604 -- The object declaration is Ghost when it is subject to pragma Ghost or
3605 -- completes a deferred Ghost constant. Set the mode now to ensure that
3606 -- any nodes generated during analysis and expansion are properly marked
3609 Set_Ghost_Mode (N, Prev_Entity);
3611 if Present (Prev_Entity) then
3612 Constant_Redeclaration (Id, N, T);
3614 Generate_Reference (Prev_Entity, Id, 'c');
3615 Set_Completion_Referenced (Id);
3617 if Error_Posted (N) then
3619 -- Type mismatch or illegal redeclaration, Do not analyze
3620 -- expression to avoid cascaded errors.
3622 T := Find_Type_Of_Object (Object_Definition (N), N);
3624 Set_Ekind (Id, E_Variable);
3628 -- In the normal case, enter identifier at the start to catch premature
3629 -- usage in the initialization expression.
3632 Generate_Definition (Id);
3635 Mark_Coextensions (N, Object_Definition (N));
3637 T := Find_Type_Of_Object (Object_Definition (N), N);
3639 if Nkind (Object_Definition (N)) = N_Access_Definition
3641 (Access_To_Subprogram_Definition (Object_Definition (N)))
3642 and then Protected_Present
3643 (Access_To_Subprogram_Definition (Object_Definition (N)))
3645 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
3648 if Error_Posted (Id) then
3650 Set_Ekind (Id, E_Variable);
3655 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
3656 -- out some static checks
3658 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
3660 -- In case of aggregates we must also take care of the correct
3661 -- initialization of nested aggregates bug this is done at the
3662 -- point of the analysis of the aggregate (see sem_aggr.adb).
3664 if Present (Expression (N))
3665 and then Nkind (Expression (N)) = N_Aggregate
3671 Save_Typ : constant Entity_Id := Etype (Id);
3673 Set_Etype (Id, T); -- Temp. decoration for static checks
3674 Null_Exclusion_Static_Checks (N);
3675 Set_Etype (Id, Save_Typ);
3680 -- Object is marked pure if it is in a pure scope
3682 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3684 -- If deferred constant, make sure context is appropriate. We detect
3685 -- a deferred constant as a constant declaration with no expression.
3686 -- A deferred constant can appear in a package body if its completion
3687 -- is by means of an interface pragma.
3689 if Constant_Present (N) and then No (E) then
3691 -- A deferred constant may appear in the declarative part of the
3692 -- following constructs:
3696 -- extended return statements
3699 -- subprogram bodies
3702 -- When declared inside a package spec, a deferred constant must be
3703 -- completed by a full constant declaration or pragma Import. In all
3704 -- other cases, the only proper completion is pragma Import. Extended
3705 -- return statements are flagged as invalid contexts because they do
3706 -- not have a declarative part and so cannot accommodate the pragma.
3708 if Ekind (Current_Scope) = E_Return_Statement then
3710 ("invalid context for deferred constant declaration (RM 7.4)",
3713 ("\declaration requires an initialization expression",
3715 Set_Constant_Present (N, False);
3717 -- In Ada 83, deferred constant must be of private type
3719 elsif not Is_Private_Type (T) then
3720 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
3722 ("(Ada 83) deferred constant must be private type", N);
3726 -- If not a deferred constant, then the object declaration freezes
3727 -- its type, unless the object is of an anonymous type and has delayed
3728 -- aspects. In that case the type is frozen when the object itself is.
3731 Check_Fully_Declared (T, N);
3733 if Has_Delayed_Aspects (Id)
3734 and then Is_Array_Type (T)
3735 and then Is_Itype (T)
3737 Set_Has_Delayed_Freeze (T);
3739 Freeze_Before (N, T);
3743 -- If the object was created by a constrained array definition, then
3744 -- set the link in both the anonymous base type and anonymous subtype
3745 -- that are built to represent the array type to point to the object.
3747 if Nkind (Object_Definition (Declaration_Node (Id))) =
3748 N_Constrained_Array_Definition
3750 Set_Related_Array_Object (T, Id);
3751 Set_Related_Array_Object (Base_Type (T), Id);
3754 -- Special checks for protected objects not at library level
3756 if Is_Protected_Type (T)
3757 and then not Is_Library_Level_Entity (Id)
3759 Check_Restriction (No_Local_Protected_Objects, Id);
3761 -- Protected objects with interrupt handlers must be at library level
3763 -- Ada 2005: This test is not needed (and the corresponding clause
3764 -- in the RM is removed) because accessibility checks are sufficient
3765 -- to make handlers not at the library level illegal.
3767 -- AI05-0303: The AI is in fact a binding interpretation, and thus
3768 -- applies to the '95 version of the language as well.
3770 if Has_Interrupt_Handler (T) and then Ada_Version < Ada_95 then
3772 ("interrupt object can only be declared at library level", Id);
3776 -- The actual subtype of the object is the nominal subtype, unless
3777 -- the nominal one is unconstrained and obtained from the expression.
3781 -- These checks should be performed before the initialization expression
3782 -- is considered, so that the Object_Definition node is still the same
3783 -- as in source code.
3785 -- In SPARK, the nominal subtype is always given by a subtype mark
3786 -- and must not be unconstrained. (The only exception to this is the
3787 -- acceptance of declarations of constants of type String.)
3789 if not Nkind_In (Object_Definition (N), N_Expanded_Name, N_Identifier)
3791 Check_SPARK_05_Restriction
3792 ("subtype mark required", Object_Definition (N));
3794 elsif Is_Array_Type (T)
3795 and then not Is_Constrained (T)
3796 and then T /= Standard_String
3798 Check_SPARK_05_Restriction
3799 ("subtype mark of constrained type expected",
3800 Object_Definition (N));
3803 -- There are no aliased objects in SPARK
3805 if Aliased_Present (N) then
3806 Check_SPARK_05_Restriction ("aliased object is not allowed", N);
3809 -- Process initialization expression if present and not in error
3811 if Present (E) and then E /= Error then
3813 -- Generate an error in case of CPP class-wide object initialization.
3814 -- Required because otherwise the expansion of the class-wide
3815 -- assignment would try to use 'size to initialize the object
3816 -- (primitive that is not available in CPP tagged types).
3818 if Is_Class_Wide_Type (Act_T)
3820 (Is_CPP_Class (Root_Type (Etype (Act_T)))
3822 (Present (Full_View (Root_Type (Etype (Act_T))))
3824 Is_CPP_Class (Full_View (Root_Type (Etype (Act_T))))))
3827 ("predefined assignment not available for 'C'P'P tagged types",
3831 Mark_Coextensions (N, E);
3834 -- In case of errors detected in the analysis of the expression,
3835 -- decorate it with the expected type to avoid cascaded errors
3837 if No (Etype (E)) then
3841 -- If an initialization expression is present, then we set the
3842 -- Is_True_Constant flag. It will be reset if this is a variable
3843 -- and it is indeed modified.
3845 Set_Is_True_Constant (Id, True);
3847 -- If we are analyzing a constant declaration, set its completion
3848 -- flag after analyzing and resolving the expression.
3850 if Constant_Present (N) then
3851 Set_Has_Completion (Id);
3854 -- Set type and resolve (type may be overridden later on). Note:
3855 -- Ekind (Id) must still be E_Void at this point so that incorrect
3856 -- early usage within E is properly diagnosed.
3860 -- If the expression is an aggregate we must look ahead to detect
3861 -- the possible presence of an address clause, and defer resolution
3862 -- and expansion of the aggregate to the freeze point of the entity.
3864 if Comes_From_Source (N)
3865 and then Expander_Active
3866 and then Nkind (E) = N_Aggregate
3867 and then (Present (Following_Address_Clause (N))
3868 or else Delayed_Aspect_Present)
3876 -- No further action needed if E is a call to an inlined function
3877 -- which returns an unconstrained type and it has been expanded into
3878 -- a procedure call. In that case N has been replaced by an object
3879 -- declaration without initializing expression and it has been
3880 -- analyzed (see Expand_Inlined_Call).
3882 if Back_End_Inlining
3883 and then Expander_Active
3884 and then Nkind (E) = N_Function_Call
3885 and then Nkind (Name (E)) in N_Has_Entity
3886 and then Is_Inlined (Entity (Name (E)))
3887 and then not Is_Constrained (Etype (E))
3888 and then Analyzed (N)
3889 and then No (Expression (N))
3891 Ghost_Mode := Save_Ghost_Mode;
3895 -- If E is null and has been replaced by an N_Raise_Constraint_Error
3896 -- node (which was marked already-analyzed), we need to set the type
3897 -- to something other than Any_Access in order to keep gigi happy.
3899 if Etype (E) = Any_Access then
3903 -- If the object is an access to variable, the initialization
3904 -- expression cannot be an access to constant.
3906 if Is_Access_Type (T)
3907 and then not Is_Access_Constant (T)
3908 and then Is_Access_Type (Etype (E))
3909 and then Is_Access_Constant (Etype (E))
3912 ("access to variable cannot be initialized with an "
3913 & "access-to-constant expression", E);
3916 if not Assignment_OK (N) then
3917 Check_Initialization (T, E);
3920 Check_Unset_Reference (E);
3922 -- If this is a variable, then set current value. If this is a
3923 -- declared constant of a scalar type with a static expression,
3924 -- indicate that it is always valid.
3926 if not Constant_Present (N) then
3927 if Compile_Time_Known_Value (E) then
3928 Set_Current_Value (Id, E);
3931 elsif Is_Scalar_Type (T) and then Is_OK_Static_Expression (E) then
3932 Set_Is_Known_Valid (Id);
3935 -- Deal with setting of null flags
3937 if Is_Access_Type (T) then
3938 if Known_Non_Null (E) then
3939 Set_Is_Known_Non_Null (Id, True);
3940 elsif Known_Null (E) and then not Can_Never_Be_Null (Id) then
3941 Set_Is_Known_Null (Id, True);
3945 -- Check incorrect use of dynamically tagged expressions
3947 if Is_Tagged_Type (T) then
3948 Check_Dynamically_Tagged_Expression
3954 Apply_Scalar_Range_Check (E, T);
3955 Apply_Static_Length_Check (E, T);
3957 if Nkind (Original_Node (N)) = N_Object_Declaration
3958 and then Comes_From_Source (Original_Node (N))
3960 -- Only call test if needed
3962 and then Restriction_Check_Required (SPARK_05)
3963 and then not Is_SPARK_05_Initialization_Expr (Original_Node (E))
3965 Check_SPARK_05_Restriction
3966 ("initialization expression is not appropriate", E);
3969 -- A formal parameter of a specific tagged type whose related
3970 -- subprogram is subject to pragma Extensions_Visible with value
3971 -- "False" cannot be implicitly converted to a class-wide type by
3972 -- means of an initialization expression (SPARK RM 6.1.7(3)).
3974 if Is_Class_Wide_Type (T) and then Is_EVF_Expression (E) then
3976 ("formal parameter with Extensions_Visible False cannot be "
3977 & "implicitly converted to class-wide type", E);
3981 -- If the No_Streams restriction is set, check that the type of the
3982 -- object is not, and does not contain, any subtype derived from
3983 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
3984 -- Has_Stream just for efficiency reasons. There is no point in
3985 -- spending time on a Has_Stream check if the restriction is not set.
3987 if Restriction_Check_Required (No_Streams) then
3988 if Has_Stream (T) then
3989 Check_Restriction (No_Streams, N);
3993 -- Deal with predicate check before we start to do major rewriting. It
3994 -- is OK to initialize and then check the initialized value, since the
3995 -- object goes out of scope if we get a predicate failure. Note that we
3996 -- do this in the analyzer and not the expander because the analyzer
3997 -- does some substantial rewriting in some cases.
3999 -- We need a predicate check if the type has predicates, and if either
4000 -- there is an initializing expression, or for default initialization
4001 -- when we have at least one case of an explicit default initial value
4002 -- and then this is not an internal declaration whose initialization
4003 -- comes later (as for an aggregate expansion).
4005 if not Suppress_Assignment_Checks (N)
4006 and then Present (Predicate_Function (T))
4007 and then not No_Initialization (N)
4011 Is_Partially_Initialized_Type (T, Include_Implicit => False))
4013 -- If the type has a static predicate and the expression is known at
4014 -- compile time, see if the expression satisfies the predicate.
4017 Check_Expression_Against_Static_Predicate (E, T);
4021 Make_Predicate_Check (T, New_Occurrence_Of (Id, Loc)));
4024 -- Case of unconstrained type
4026 if not Is_Definite_Subtype (T) then
4028 -- In SPARK, a declaration of unconstrained type is allowed
4029 -- only for constants of type string.
4031 if Is_String_Type (T) and then not Constant_Present (N) then
4032 Check_SPARK_05_Restriction
4033 ("declaration of object of unconstrained type not allowed", N);
4036 -- Nothing to do in deferred constant case
4038 if Constant_Present (N) and then No (E) then
4041 -- Case of no initialization present
4044 if No_Initialization (N) then
4047 elsif Is_Class_Wide_Type (T) then
4049 ("initialization required in class-wide declaration ", N);
4053 ("unconstrained subtype not allowed (need initialization)",
4054 Object_Definition (N));
4056 if Is_Record_Type (T) and then Has_Discriminants (T) then
4058 ("\provide initial value or explicit discriminant values",
4059 Object_Definition (N));
4062 ("\or give default discriminant values for type&",
4063 Object_Definition (N), T);
4065 elsif Is_Array_Type (T) then
4067 ("\provide initial value or explicit array bounds",
4068 Object_Definition (N));
4072 -- Case of initialization present but in error. Set initial
4073 -- expression as absent (but do not make above complaints)
4075 elsif E = Error then
4076 Set_Expression (N, Empty);
4079 -- Case of initialization present
4082 -- Check restrictions in Ada 83
4084 if not Constant_Present (N) then
4086 -- Unconstrained variables not allowed in Ada 83 mode
4088 if Ada_Version = Ada_83
4089 and then Comes_From_Source (Object_Definition (N))
4092 ("(Ada 83) unconstrained variable not allowed",
4093 Object_Definition (N));
4097 -- Now we constrain the variable from the initializing expression
4099 -- If the expression is an aggregate, it has been expanded into
4100 -- individual assignments. Retrieve the actual type from the
4101 -- expanded construct.
4103 if Is_Array_Type (T)
4104 and then No_Initialization (N)
4105 and then Nkind (Original_Node (E)) = N_Aggregate
4109 -- In case of class-wide interface object declarations we delay
4110 -- the generation of the equivalent record type declarations until
4111 -- its expansion because there are cases in they are not required.
4113 elsif Is_Interface (T) then
4116 -- In GNATprove mode, Expand_Subtype_From_Expr does nothing. Thus,
4117 -- we should prevent the generation of another Itype with the
4118 -- same name as the one already generated, or we end up with
4119 -- two identical types in GNATprove.
4121 elsif GNATprove_Mode then
4124 -- If the type is an unchecked union, no subtype can be built from
4125 -- the expression. Rewrite declaration as a renaming, which the
4126 -- back-end can handle properly. This is a rather unusual case,
4127 -- because most unchecked_union declarations have default values
4128 -- for discriminants and are thus not indefinite.
4130 elsif Is_Unchecked_Union (T) then
4131 if Constant_Present (N) or else Nkind (E) = N_Function_Call then
4132 Set_Ekind (Id, E_Constant);
4134 Set_Ekind (Id, E_Variable);
4137 -- An object declared within a Ghost region is automatically
4138 -- Ghost (SPARK RM 6.9(2)).
4140 if Comes_From_Source (Id) and then Ghost_Mode > None then
4141 Set_Is_Ghost_Entity (Id);
4143 -- The Ghost policy in effect at the point of declaration
4144 -- and at the point of completion must match
4145 -- (SPARK RM 6.9(14)).
4147 if Present (Prev_Entity)
4148 and then Is_Ghost_Entity (Prev_Entity)
4150 Check_Ghost_Completion (Prev_Entity, Id);
4155 Make_Object_Renaming_Declaration (Loc,
4156 Defining_Identifier => Id,
4157 Subtype_Mark => New_Occurrence_Of (T, Loc),
4160 Set_Renamed_Object (Id, E);
4161 Freeze_Before (N, T);
4164 Ghost_Mode := Save_Ghost_Mode;
4168 Expand_Subtype_From_Expr (N, T, Object_Definition (N), E);
4169 Act_T := Find_Type_Of_Object (Object_Definition (N), N);
4172 Set_Is_Constr_Subt_For_U_Nominal (Act_T);
4174 if Aliased_Present (N) then
4175 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
4178 Freeze_Before (N, Act_T);
4179 Freeze_Before (N, T);
4182 elsif Is_Array_Type (T)
4183 and then No_Initialization (N)
4184 and then Nkind (Original_Node (E)) = N_Aggregate
4186 if not Is_Entity_Name (Object_Definition (N)) then
4188 Check_Compile_Time_Size (Act_T);
4190 if Aliased_Present (N) then
4191 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
4195 -- When the given object definition and the aggregate are specified
4196 -- independently, and their lengths might differ do a length check.
4197 -- This cannot happen if the aggregate is of the form (others =>...)
4199 if not Is_Constrained (T) then
4202 elsif Nkind (E) = N_Raise_Constraint_Error then
4204 -- Aggregate is statically illegal. Place back in declaration
4206 Set_Expression (N, E);
4207 Set_No_Initialization (N, False);
4209 elsif T = Etype (E) then
4212 elsif Nkind (E) = N_Aggregate
4213 and then Present (Component_Associations (E))
4214 and then Present (Choices (First (Component_Associations (E))))
4215 and then Nkind (First
4216 (Choices (First (Component_Associations (E))))) = N_Others_Choice
4221 Apply_Length_Check (E, T);
4224 -- If the type is limited unconstrained with defaulted discriminants and
4225 -- there is no expression, then the object is constrained by the
4226 -- defaults, so it is worthwhile building the corresponding subtype.
4228 elsif (Is_Limited_Record (T) or else Is_Concurrent_Type (T))
4229 and then not Is_Constrained (T)
4230 and then Has_Discriminants (T)
4233 Act_T := Build_Default_Subtype (T, N);
4235 -- Ada 2005: A limited object may be initialized by means of an
4236 -- aggregate. If the type has default discriminants it has an
4237 -- unconstrained nominal type, Its actual subtype will be obtained
4238 -- from the aggregate, and not from the default discriminants.
4243 Rewrite (Object_Definition (N), New_Occurrence_Of (Act_T, Loc));
4245 elsif Nkind (E) = N_Function_Call
4246 and then Constant_Present (N)
4247 and then Has_Unconstrained_Elements (Etype (E))
4249 -- The back-end has problems with constants of a discriminated type
4250 -- with defaults, if the initial value is a function call. We
4251 -- generate an intermediate temporary that will receive a reference
4252 -- to the result of the call. The initialization expression then
4253 -- becomes a dereference of that temporary.
4255 Remove_Side_Effects (E);
4257 -- If this is a constant declaration of an unconstrained type and
4258 -- the initialization is an aggregate, we can use the subtype of the
4259 -- aggregate for the declared entity because it is immutable.
4261 elsif not Is_Constrained (T)
4262 and then Has_Discriminants (T)
4263 and then Constant_Present (N)
4264 and then not Has_Unchecked_Union (T)
4265 and then Nkind (E) = N_Aggregate
4270 -- Check No_Wide_Characters restriction
4272 Check_Wide_Character_Restriction (T, Object_Definition (N));
4274 -- Indicate this is not set in source. Certainly true for constants, and
4275 -- true for variables so far (will be reset for a variable if and when
4276 -- we encounter a modification in the source).
4278 Set_Never_Set_In_Source (Id);
4280 -- Now establish the proper kind and type of the object
4282 if Constant_Present (N) then
4283 Set_Ekind (Id, E_Constant);
4284 Set_Is_True_Constant (Id);
4287 Set_Ekind (Id, E_Variable);
4289 -- A variable is set as shared passive if it appears in a shared
4290 -- passive package, and is at the outer level. This is not done for
4291 -- entities generated during expansion, because those are always
4292 -- manipulated locally.
4294 if Is_Shared_Passive (Current_Scope)
4295 and then Is_Library_Level_Entity (Id)
4296 and then Comes_From_Source (Id)
4298 Set_Is_Shared_Passive (Id);
4299 Check_Shared_Var (Id, T, N);
4302 -- Set Has_Initial_Value if initializing expression present. Note
4303 -- that if there is no initializing expression, we leave the state
4304 -- of this flag unchanged (usually it will be False, but notably in
4305 -- the case of exception choice variables, it will already be true).
4308 Set_Has_Initial_Value (Id);
4312 -- Initialize alignment and size and capture alignment setting
4314 Init_Alignment (Id);
4316 Set_Optimize_Alignment_Flags (Id);
4318 -- An object declared within a Ghost region is automatically Ghost
4319 -- (SPARK RM 6.9(2)).
4321 if Comes_From_Source (Id)
4322 and then (Ghost_Mode > None
4323 or else (Present (Prev_Entity)
4324 and then Is_Ghost_Entity (Prev_Entity)))
4326 Set_Is_Ghost_Entity (Id);
4328 -- The Ghost policy in effect at the point of declaration and at the
4329 -- point of completion must match (SPARK RM 6.9(14)).
4331 if Present (Prev_Entity) and then Is_Ghost_Entity (Prev_Entity) then
4332 Check_Ghost_Completion (Prev_Entity, Id);
4336 -- Deal with aliased case
4338 if Aliased_Present (N) then
4339 Set_Is_Aliased (Id);
4341 -- If the object is aliased and the type is unconstrained with
4342 -- defaulted discriminants and there is no expression, then the
4343 -- object is constrained by the defaults, so it is worthwhile
4344 -- building the corresponding subtype.
4346 -- Ada 2005 (AI-363): If the aliased object is discriminated and
4347 -- unconstrained, then only establish an actual subtype if the
4348 -- nominal subtype is indefinite. In definite cases the object is
4349 -- unconstrained in Ada 2005.
4352 and then Is_Record_Type (T)
4353 and then not Is_Constrained (T)
4354 and then Has_Discriminants (T)
4355 and then (Ada_Version < Ada_2005
4356 or else not Is_Definite_Subtype (T))
4358 Set_Actual_Subtype (Id, Build_Default_Subtype (T, N));
4362 -- Now we can set the type of the object
4364 Set_Etype (Id, Act_T);
4366 -- Non-constant object is marked to be treated as volatile if type is
4367 -- volatile and we clear the Current_Value setting that may have been
4368 -- set above. Doing so for constants isn't required and might interfere
4369 -- with possible uses of the object as a static expression in contexts
4370 -- incompatible with volatility (e.g. as a case-statement alternative).
4372 if Ekind (Id) /= E_Constant and then Treat_As_Volatile (Etype (Id)) then
4373 Set_Treat_As_Volatile (Id);
4374 Set_Current_Value (Id, Empty);
4377 -- Deal with controlled types
4379 if Has_Controlled_Component (Etype (Id))
4380 or else Is_Controlled (Etype (Id))
4382 if not Is_Library_Level_Entity (Id) then
4383 Check_Restriction (No_Nested_Finalization, N);
4385 Validate_Controlled_Object (Id);
4389 if Has_Task (Etype (Id)) then
4390 Check_Restriction (No_Tasking, N);
4392 -- Deal with counting max tasks
4394 -- Nothing to do if inside a generic
4396 if Inside_A_Generic then
4399 -- If library level entity, then count tasks
4401 elsif Is_Library_Level_Entity (Id) then
4402 Check_Restriction (Max_Tasks, N, Count_Tasks (Etype (Id)));
4404 -- If not library level entity, then indicate we don't know max
4405 -- tasks and also check task hierarchy restriction and blocking
4406 -- operation (since starting a task is definitely blocking).
4409 Check_Restriction (Max_Tasks, N);
4410 Check_Restriction (No_Task_Hierarchy, N);
4411 Check_Potentially_Blocking_Operation (N);
4414 -- A rather specialized test. If we see two tasks being declared
4415 -- of the same type in the same object declaration, and the task
4416 -- has an entry with an address clause, we know that program error
4417 -- will be raised at run time since we can't have two tasks with
4418 -- entries at the same address.
4420 if Is_Task_Type (Etype (Id)) and then More_Ids (N) then
4425 E := First_Entity (Etype (Id));
4426 while Present (E) loop
4427 if Ekind (E) = E_Entry
4428 and then Present (Get_Attribute_Definition_Clause
4429 (E, Attribute_Address))
4431 Error_Msg_Warn := SPARK_Mode /= On;
4433 ("more than one task with same entry address<<", N);
4434 Error_Msg_N ("\Program_Error [<<", N);
4436 Make_Raise_Program_Error (Loc,
4437 Reason => PE_Duplicated_Entry_Address));
4447 -- Some simple constant-propagation: if the expression is a constant
4448 -- string initialized with a literal, share the literal. This avoids
4452 and then Is_Entity_Name (E)
4453 and then Ekind (Entity (E)) = E_Constant
4454 and then Base_Type (Etype (E)) = Standard_String
4457 Val : constant Node_Id := Constant_Value (Entity (E));
4459 if Present (Val) and then Nkind (Val) = N_String_Literal then
4460 Rewrite (E, New_Copy (Val));
4465 -- Another optimization: if the nominal subtype is unconstrained and
4466 -- the expression is a function call that returns an unconstrained
4467 -- type, rewrite the declaration as a renaming of the result of the
4468 -- call. The exceptions below are cases where the copy is expected,
4469 -- either by the back end (Aliased case) or by the semantics, as for
4470 -- initializing controlled types or copying tags for classwide types.
4473 and then Nkind (E) = N_Explicit_Dereference
4474 and then Nkind (Original_Node (E)) = N_Function_Call
4475 and then not Is_Library_Level_Entity (Id)
4476 and then not Is_Constrained (Underlying_Type (T))
4477 and then not Is_Aliased (Id)
4478 and then not Is_Class_Wide_Type (T)
4479 and then not Is_Controlled_Active (T)
4480 and then not Has_Controlled_Component (Base_Type (T))
4481 and then Expander_Active
4484 Make_Object_Renaming_Declaration (Loc,
4485 Defining_Identifier => Id,
4486 Access_Definition => Empty,
4487 Subtype_Mark => New_Occurrence_Of
4488 (Base_Type (Etype (Id)), Loc),
4491 Set_Renamed_Object (Id, E);
4493 -- Force generation of debugging information for the constant and for
4494 -- the renamed function call.
4496 Set_Debug_Info_Needed (Id);
4497 Set_Debug_Info_Needed (Entity (Prefix (E)));
4500 if Present (Prev_Entity)
4501 and then Is_Frozen (Prev_Entity)
4502 and then not Error_Posted (Id)
4504 Error_Msg_N ("full constant declaration appears too late", N);
4507 Check_Eliminated (Id);
4509 -- Deal with setting In_Private_Part flag if in private part
4511 if Ekind (Scope (Id)) = E_Package
4512 and then In_Private_Part (Scope (Id))
4514 Set_In_Private_Part (Id);
4517 -- Check for violation of No_Local_Timing_Events
4519 if Restriction_Check_Required (No_Local_Timing_Events)
4520 and then not Is_Library_Level_Entity (Id)
4521 and then Is_RTE (Etype (Id), RE_Timing_Event)
4523 Check_Restriction (No_Local_Timing_Events, N);
4527 -- Initialize the refined state of a variable here because this is a
4528 -- common destination for legal and illegal object declarations.
4530 if Ekind (Id) = E_Variable then
4531 Set_Encapsulating_State (Id, Empty);
4534 if Has_Aspects (N) then
4535 Analyze_Aspect_Specifications (N, Id);
4538 Analyze_Dimension (N);
4540 -- Verify whether the object declaration introduces an illegal hidden
4541 -- state within a package subject to a null abstract state.
4543 if Ekind (Id) = E_Variable then
4544 Check_No_Hidden_State (Id);
4547 Ghost_Mode := Save_Ghost_Mode;
4548 end Analyze_Object_Declaration;
4550 ---------------------------
4551 -- Analyze_Others_Choice --
4552 ---------------------------
4554 -- Nothing to do for the others choice node itself, the semantic analysis
4555 -- of the others choice will occur as part of the processing of the parent
4557 procedure Analyze_Others_Choice (N : Node_Id) is
4558 pragma Warnings (Off, N);
4561 end Analyze_Others_Choice;
4563 -------------------------------------------
4564 -- Analyze_Private_Extension_Declaration --
4565 -------------------------------------------
4567 procedure Analyze_Private_Extension_Declaration (N : Node_Id) is
4568 Indic : constant Node_Id := Subtype_Indication (N);
4569 T : constant Entity_Id := Defining_Identifier (N);
4570 Parent_Base : Entity_Id;
4571 Parent_Type : Entity_Id;
4574 -- Ada 2005 (AI-251): Decorate all names in list of ancestor interfaces
4576 if Is_Non_Empty_List (Interface_List (N)) then
4582 Intf := First (Interface_List (N));
4583 while Present (Intf) loop
4584 T := Find_Type_Of_Subtype_Indic (Intf);
4586 Diagnose_Interface (Intf, T);
4592 Generate_Definition (T);
4594 -- For other than Ada 2012, just enter the name in the current scope
4596 if Ada_Version < Ada_2012 then
4599 -- Ada 2012 (AI05-0162): Enter the name in the current scope handling
4600 -- case of private type that completes an incomplete type.
4607 Prev := Find_Type_Name (N);
4609 pragma Assert (Prev = T
4610 or else (Ekind (Prev) = E_Incomplete_Type
4611 and then Present (Full_View (Prev))
4612 and then Full_View (Prev) = T));
4616 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
4617 Parent_Base := Base_Type (Parent_Type);
4619 if Parent_Type = Any_Type or else Etype (Parent_Type) = Any_Type then
4620 Set_Ekind (T, Ekind (Parent_Type));
4621 Set_Etype (T, Any_Type);
4624 elsif not Is_Tagged_Type (Parent_Type) then
4626 ("parent of type extension must be a tagged type ", Indic);
4629 elsif Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
4630 Error_Msg_N ("premature derivation of incomplete type", Indic);
4633 elsif Is_Concurrent_Type (Parent_Type) then
4635 ("parent type of a private extension cannot be "
4636 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
4638 Set_Etype (T, Any_Type);
4639 Set_Ekind (T, E_Limited_Private_Type);
4640 Set_Private_Dependents (T, New_Elmt_List);
4641 Set_Error_Posted (T);
4645 -- Perhaps the parent type should be changed to the class-wide type's
4646 -- specific type in this case to prevent cascading errors ???
4648 if Is_Class_Wide_Type (Parent_Type) then
4650 ("parent of type extension must not be a class-wide type", Indic);
4654 if (not Is_Package_Or_Generic_Package (Current_Scope)
4655 and then Nkind (Parent (N)) /= N_Generic_Subprogram_Declaration)
4656 or else In_Private_Part (Current_Scope)
4659 Error_Msg_N ("invalid context for private extension", N);
4662 -- Set common attributes
4664 Set_Is_Pure (T, Is_Pure (Current_Scope));
4665 Set_Scope (T, Current_Scope);
4666 Set_Ekind (T, E_Record_Type_With_Private);
4667 Init_Size_Align (T);
4668 Set_Default_SSO (T);
4670 Set_Etype (T, Parent_Base);
4671 Set_Has_Task (T, Has_Task (Parent_Base));
4672 Set_Has_Protected (T, Has_Task (Parent_Base));
4674 Set_Convention (T, Convention (Parent_Type));
4675 Set_First_Rep_Item (T, First_Rep_Item (Parent_Type));
4676 Set_Is_First_Subtype (T);
4677 Make_Class_Wide_Type (T);
4679 if Unknown_Discriminants_Present (N) then
4680 Set_Discriminant_Constraint (T, No_Elist);
4683 Build_Derived_Record_Type (N, Parent_Type, T);
4685 -- Propagate inherited invariant information. The new type has
4686 -- invariants, if the parent type has inheritable invariants,
4687 -- and these invariants can in turn be inherited.
4689 if Has_Inheritable_Invariants (Parent_Type) then
4690 Set_Has_Inheritable_Invariants (T);
4691 Set_Has_Invariants (T);
4694 -- Ada 2005 (AI-443): Synchronized private extension or a rewritten
4695 -- synchronized formal derived type.
4697 if Ada_Version >= Ada_2005 and then Synchronized_Present (N) then
4698 Set_Is_Limited_Record (T);
4700 -- Formal derived type case
4702 if Is_Generic_Type (T) then
4704 -- The parent must be a tagged limited type or a synchronized
4707 if (not Is_Tagged_Type (Parent_Type)
4708 or else not Is_Limited_Type (Parent_Type))
4710 (not Is_Interface (Parent_Type)
4711 or else not Is_Synchronized_Interface (Parent_Type))
4713 Error_Msg_NE ("parent type of & must be tagged limited " &
4714 "or synchronized", N, T);
4717 -- The progenitors (if any) must be limited or synchronized
4720 if Present (Interfaces (T)) then
4723 Iface_Elmt : Elmt_Id;
4726 Iface_Elmt := First_Elmt (Interfaces (T));
4727 while Present (Iface_Elmt) loop
4728 Iface := Node (Iface_Elmt);
4730 if not Is_Limited_Interface (Iface)
4731 and then not Is_Synchronized_Interface (Iface)
4733 Error_Msg_NE ("progenitor & must be limited " &
4734 "or synchronized", N, Iface);
4737 Next_Elmt (Iface_Elmt);
4742 -- Regular derived extension, the parent must be a limited or
4743 -- synchronized interface.
4746 if not Is_Interface (Parent_Type)
4747 or else (not Is_Limited_Interface (Parent_Type)
4748 and then not Is_Synchronized_Interface (Parent_Type))
4751 ("parent type of & must be limited interface", N, T);
4755 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
4756 -- extension with a synchronized parent must be explicitly declared
4757 -- synchronized, because the full view will be a synchronized type.
4758 -- This must be checked before the check for limited types below,
4759 -- to ensure that types declared limited are not allowed to extend
4760 -- synchronized interfaces.
4762 elsif Is_Interface (Parent_Type)
4763 and then Is_Synchronized_Interface (Parent_Type)
4764 and then not Synchronized_Present (N)
4767 ("private extension of& must be explicitly synchronized",
4770 elsif Limited_Present (N) then
4771 Set_Is_Limited_Record (T);
4773 if not Is_Limited_Type (Parent_Type)
4775 (not Is_Interface (Parent_Type)
4776 or else not Is_Limited_Interface (Parent_Type))
4778 Error_Msg_NE ("parent type& of limited extension must be limited",
4784 if Has_Aspects (N) then
4785 Analyze_Aspect_Specifications (N, T);
4787 end Analyze_Private_Extension_Declaration;
4789 ---------------------------------
4790 -- Analyze_Subtype_Declaration --
4791 ---------------------------------
4793 procedure Analyze_Subtype_Declaration
4795 Skip : Boolean := False)
4797 Id : constant Entity_Id := Defining_Identifier (N);
4798 R_Checks : Check_Result;
4802 Generate_Definition (Id);
4803 Set_Is_Pure (Id, Is_Pure (Current_Scope));
4804 Init_Size_Align (Id);
4806 -- The following guard condition on Enter_Name is to handle cases where
4807 -- the defining identifier has already been entered into the scope but
4808 -- the declaration as a whole needs to be analyzed.
4810 -- This case in particular happens for derived enumeration types. The
4811 -- derived enumeration type is processed as an inserted enumeration type
4812 -- declaration followed by a rewritten subtype declaration. The defining
4813 -- identifier, however, is entered into the name scope very early in the
4814 -- processing of the original type declaration and therefore needs to be
4815 -- avoided here, when the created subtype declaration is analyzed. (See
4816 -- Build_Derived_Types)
4818 -- This also happens when the full view of a private type is derived
4819 -- type with constraints. In this case the entity has been introduced
4820 -- in the private declaration.
4822 -- Finally this happens in some complex cases when validity checks are
4823 -- enabled, where the same subtype declaration may be analyzed twice.
4824 -- This can happen if the subtype is created by the pre-analysis of
4825 -- an attribute tht gives the range of a loop statement, and the loop
4826 -- itself appears within an if_statement that will be rewritten during
4830 or else (Present (Etype (Id))
4831 and then (Is_Private_Type (Etype (Id))
4832 or else Is_Task_Type (Etype (Id))
4833 or else Is_Rewrite_Substitution (N)))
4837 elsif Current_Entity (Id) = Id then
4844 T := Process_Subtype (Subtype_Indication (N), N, Id, 'P');
4846 -- Class-wide equivalent types of records with unknown discriminants
4847 -- involve the generation of an itype which serves as the private view
4848 -- of a constrained record subtype. In such cases the base type of the
4849 -- current subtype we are processing is the private itype. Use the full
4850 -- of the private itype when decorating various attributes.
4853 and then Is_Private_Type (T)
4854 and then Present (Full_View (T))
4859 -- Inherit common attributes
4861 Set_Is_Volatile (Id, Is_Volatile (T));
4862 Set_Treat_As_Volatile (Id, Treat_As_Volatile (T));
4863 Set_Is_Generic_Type (Id, Is_Generic_Type (Base_Type (T)));
4864 Set_Convention (Id, Convention (T));
4866 -- If ancestor has predicates then so does the subtype, and in addition
4867 -- we must delay the freeze to properly arrange predicate inheritance.
4869 -- The Ancestor_Type test is really unpleasant, there seem to be cases
4870 -- in which T = ID, so the above tests and assignments do nothing???
4872 if Has_Predicates (T)
4873 or else (Present (Ancestor_Subtype (T))
4874 and then Has_Predicates (Ancestor_Subtype (T)))
4876 Set_Has_Predicates (Id);
4877 Set_Has_Delayed_Freeze (Id);
4880 -- Subtype of Boolean cannot have a constraint in SPARK
4882 if Is_Boolean_Type (T)
4883 and then Nkind (Subtype_Indication (N)) = N_Subtype_Indication
4885 Check_SPARK_05_Restriction
4886 ("subtype of Boolean cannot have constraint", N);
4889 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4891 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
4897 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint then
4898 One_Cstr := First (Constraints (Cstr));
4899 while Present (One_Cstr) loop
4901 -- Index or discriminant constraint in SPARK must be a
4905 Nkind_In (One_Cstr, N_Identifier, N_Expanded_Name)
4907 Check_SPARK_05_Restriction
4908 ("subtype mark required", One_Cstr);
4910 -- String subtype must have a lower bound of 1 in SPARK.
4911 -- Note that we do not need to test for the non-static case
4912 -- here, since that was already taken care of in
4913 -- Process_Range_Expr_In_Decl.
4915 elsif Base_Type (T) = Standard_String then
4916 Get_Index_Bounds (One_Cstr, Low, High);
4918 if Is_OK_Static_Expression (Low)
4919 and then Expr_Value (Low) /= 1
4921 Check_SPARK_05_Restriction
4922 ("String subtype must have lower bound of 1", N);
4932 -- In the case where there is no constraint given in the subtype
4933 -- indication, Process_Subtype just returns the Subtype_Mark, so its
4934 -- semantic attributes must be established here.
4936 if Nkind (Subtype_Indication (N)) /= N_Subtype_Indication then
4937 Set_Etype (Id, Base_Type (T));
4939 -- Subtype of unconstrained array without constraint is not allowed
4942 if Is_Array_Type (T) and then not Is_Constrained (T) then
4943 Check_SPARK_05_Restriction
4944 ("subtype of unconstrained array must have constraint", N);
4949 Set_Ekind (Id, E_Array_Subtype);
4950 Copy_Array_Subtype_Attributes (Id, T);
4952 when Decimal_Fixed_Point_Kind =>
4953 Set_Ekind (Id, E_Decimal_Fixed_Point_Subtype);
4954 Set_Digits_Value (Id, Digits_Value (T));
4955 Set_Delta_Value (Id, Delta_Value (T));
4956 Set_Scale_Value (Id, Scale_Value (T));
4957 Set_Small_Value (Id, Small_Value (T));
4958 Set_Scalar_Range (Id, Scalar_Range (T));
4959 Set_Machine_Radix_10 (Id, Machine_Radix_10 (T));
4960 Set_Is_Constrained (Id, Is_Constrained (T));
4961 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4962 Set_RM_Size (Id, RM_Size (T));
4964 when Enumeration_Kind =>
4965 Set_Ekind (Id, E_Enumeration_Subtype);
4966 Set_First_Literal (Id, First_Literal (Base_Type (T)));
4967 Set_Scalar_Range (Id, Scalar_Range (T));
4968 Set_Is_Character_Type (Id, Is_Character_Type (T));
4969 Set_Is_Constrained (Id, Is_Constrained (T));
4970 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4971 Set_RM_Size (Id, RM_Size (T));
4972 Inherit_Predicate_Flags (Id, T);
4974 when Ordinary_Fixed_Point_Kind =>
4975 Set_Ekind (Id, E_Ordinary_Fixed_Point_Subtype);
4976 Set_Scalar_Range (Id, Scalar_Range (T));
4977 Set_Small_Value (Id, Small_Value (T));
4978 Set_Delta_Value (Id, Delta_Value (T));
4979 Set_Is_Constrained (Id, Is_Constrained (T));
4980 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4981 Set_RM_Size (Id, RM_Size (T));
4984 Set_Ekind (Id, E_Floating_Point_Subtype);
4985 Set_Scalar_Range (Id, Scalar_Range (T));
4986 Set_Digits_Value (Id, Digits_Value (T));
4987 Set_Is_Constrained (Id, Is_Constrained (T));
4989 when Signed_Integer_Kind =>
4990 Set_Ekind (Id, E_Signed_Integer_Subtype);
4991 Set_Scalar_Range (Id, Scalar_Range (T));
4992 Set_Is_Constrained (Id, Is_Constrained (T));
4993 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4994 Set_RM_Size (Id, RM_Size (T));
4995 Inherit_Predicate_Flags (Id, T);
4997 when Modular_Integer_Kind =>
4998 Set_Ekind (Id, E_Modular_Integer_Subtype);
4999 Set_Scalar_Range (Id, Scalar_Range (T));
5000 Set_Is_Constrained (Id, Is_Constrained (T));
5001 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
5002 Set_RM_Size (Id, RM_Size (T));
5003 Inherit_Predicate_Flags (Id, T);
5005 when Class_Wide_Kind =>
5006 Set_Ekind (Id, E_Class_Wide_Subtype);
5007 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
5008 Set_Cloned_Subtype (Id, T);
5009 Set_Is_Tagged_Type (Id, True);
5010 Set_Has_Unknown_Discriminants
5012 Set_No_Tagged_Streams_Pragma
5013 (Id, No_Tagged_Streams_Pragma (T));
5015 if Ekind (T) = E_Class_Wide_Subtype then
5016 Set_Equivalent_Type (Id, Equivalent_Type (T));
5019 when E_Record_Type | E_Record_Subtype =>
5020 Set_Ekind (Id, E_Record_Subtype);
5022 if Ekind (T) = E_Record_Subtype
5023 and then Present (Cloned_Subtype (T))
5025 Set_Cloned_Subtype (Id, Cloned_Subtype (T));
5027 Set_Cloned_Subtype (Id, T);
5030 Set_First_Entity (Id, First_Entity (T));
5031 Set_Last_Entity (Id, Last_Entity (T));
5032 Set_Has_Discriminants (Id, Has_Discriminants (T));
5033 Set_Is_Constrained (Id, Is_Constrained (T));
5034 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
5035 Set_Has_Implicit_Dereference
5036 (Id, Has_Implicit_Dereference (T));
5037 Set_Has_Unknown_Discriminants
5038 (Id, Has_Unknown_Discriminants (T));
5040 if Has_Discriminants (T) then
5041 Set_Discriminant_Constraint
5042 (Id, Discriminant_Constraint (T));
5043 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5045 elsif Has_Unknown_Discriminants (Id) then
5046 Set_Discriminant_Constraint (Id, No_Elist);
5049 if Is_Tagged_Type (T) then
5050 Set_Is_Tagged_Type (Id, True);
5051 Set_No_Tagged_Streams_Pragma
5052 (Id, No_Tagged_Streams_Pragma (T));
5053 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
5054 Set_Direct_Primitive_Operations
5055 (Id, Direct_Primitive_Operations (T));
5056 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
5058 if Is_Interface (T) then
5059 Set_Is_Interface (Id);
5060 Set_Is_Limited_Interface (Id, Is_Limited_Interface (T));
5064 when Private_Kind =>
5065 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
5066 Set_Has_Discriminants (Id, Has_Discriminants (T));
5067 Set_Is_Constrained (Id, Is_Constrained (T));
5068 Set_First_Entity (Id, First_Entity (T));
5069 Set_Last_Entity (Id, Last_Entity (T));
5070 Set_Private_Dependents (Id, New_Elmt_List);
5071 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
5072 Set_Has_Implicit_Dereference
5073 (Id, Has_Implicit_Dereference (T));
5074 Set_Has_Unknown_Discriminants
5075 (Id, Has_Unknown_Discriminants (T));
5076 Set_Known_To_Have_Preelab_Init
5077 (Id, Known_To_Have_Preelab_Init (T));
5079 if Is_Tagged_Type (T) then
5080 Set_Is_Tagged_Type (Id);
5081 Set_No_Tagged_Streams_Pragma (Id,
5082 No_Tagged_Streams_Pragma (T));
5083 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
5084 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
5085 Set_Direct_Primitive_Operations (Id,
5086 Direct_Primitive_Operations (T));
5089 -- In general the attributes of the subtype of a private type
5090 -- are the attributes of the partial view of parent. However,
5091 -- the full view may be a discriminated type, and the subtype
5092 -- must share the discriminant constraint to generate correct
5093 -- calls to initialization procedures.
5095 if Has_Discriminants (T) then
5096 Set_Discriminant_Constraint
5097 (Id, Discriminant_Constraint (T));
5098 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5100 elsif Present (Full_View (T))
5101 and then Has_Discriminants (Full_View (T))
5103 Set_Discriminant_Constraint
5104 (Id, Discriminant_Constraint (Full_View (T)));
5105 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5107 -- This would seem semantically correct, but apparently
5108 -- generates spurious errors about missing components ???
5110 -- Set_Has_Discriminants (Id);
5113 Prepare_Private_Subtype_Completion (Id, N);
5115 -- If this is the subtype of a constrained private type with
5116 -- discriminants that has got a full view and we also have
5117 -- built a completion just above, show that the completion
5118 -- is a clone of the full view to the back-end.
5120 if Has_Discriminants (T)
5121 and then not Has_Unknown_Discriminants (T)
5122 and then not Is_Empty_Elmt_List (Discriminant_Constraint (T))
5123 and then Present (Full_View (T))
5124 and then Present (Full_View (Id))
5126 Set_Cloned_Subtype (Full_View (Id), Full_View (T));
5130 Set_Ekind (Id, E_Access_Subtype);
5131 Set_Is_Constrained (Id, Is_Constrained (T));
5132 Set_Is_Access_Constant
5133 (Id, Is_Access_Constant (T));
5134 Set_Directly_Designated_Type
5135 (Id, Designated_Type (T));
5136 Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T));
5138 -- A Pure library_item must not contain the declaration of a
5139 -- named access type, except within a subprogram, generic
5140 -- subprogram, task unit, or protected unit, or if it has
5141 -- a specified Storage_Size of zero (RM05-10.2.1(15.4-15.5)).
5143 if Comes_From_Source (Id)
5144 and then In_Pure_Unit
5145 and then not In_Subprogram_Task_Protected_Unit
5146 and then not No_Pool_Assigned (Id)
5149 ("named access types not allowed in pure unit", N);
5152 when Concurrent_Kind =>
5153 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
5154 Set_Corresponding_Record_Type (Id,
5155 Corresponding_Record_Type (T));
5156 Set_First_Entity (Id, First_Entity (T));
5157 Set_First_Private_Entity (Id, First_Private_Entity (T));
5158 Set_Has_Discriminants (Id, Has_Discriminants (T));
5159 Set_Is_Constrained (Id, Is_Constrained (T));
5160 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
5161 Set_Last_Entity (Id, Last_Entity (T));
5163 if Is_Tagged_Type (T) then
5164 Set_No_Tagged_Streams_Pragma
5165 (Id, No_Tagged_Streams_Pragma (T));
5168 if Has_Discriminants (T) then
5169 Set_Discriminant_Constraint
5170 (Id, Discriminant_Constraint (T));
5171 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5174 when Incomplete_Kind =>
5175 if Ada_Version >= Ada_2005 then
5177 -- In Ada 2005 an incomplete type can be explicitly tagged:
5178 -- propagate indication. Note that we also have to include
5179 -- subtypes for Ada 2012 extended use of incomplete types.
5181 Set_Ekind (Id, E_Incomplete_Subtype);
5182 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
5183 Set_Private_Dependents (Id, New_Elmt_List);
5185 if Is_Tagged_Type (Id) then
5186 Set_No_Tagged_Streams_Pragma
5187 (Id, No_Tagged_Streams_Pragma (T));
5188 Set_Direct_Primitive_Operations (Id, New_Elmt_List);
5191 -- Ada 2005 (AI-412): Decorate an incomplete subtype of an
5192 -- incomplete type visible through a limited with clause.
5194 if From_Limited_With (T)
5195 and then Present (Non_Limited_View (T))
5197 Set_From_Limited_With (Id);
5198 Set_Non_Limited_View (Id, Non_Limited_View (T));
5200 -- Ada 2005 (AI-412): Add the regular incomplete subtype
5201 -- to the private dependents of the original incomplete
5202 -- type for future transformation.
5205 Append_Elmt (Id, Private_Dependents (T));
5208 -- If the subtype name denotes an incomplete type an error
5209 -- was already reported by Process_Subtype.
5212 Set_Etype (Id, Any_Type);
5216 raise Program_Error;
5220 if Etype (Id) = Any_Type then
5224 -- Some common processing on all types
5226 Set_Size_Info (Id, T);
5227 Set_First_Rep_Item (Id, First_Rep_Item (T));
5229 -- If the parent type is a generic actual, so is the subtype. This may
5230 -- happen in a nested instance. Why Comes_From_Source test???
5232 if not Comes_From_Source (N) then
5233 Set_Is_Generic_Actual_Type (Id, Is_Generic_Actual_Type (T));
5238 Set_Is_Immediately_Visible (Id, True);
5239 Set_Depends_On_Private (Id, Has_Private_Component (T));
5240 Set_Is_Descendent_Of_Address (Id, Is_Descendent_Of_Address (T));
5242 if Is_Interface (T) then
5243 Set_Is_Interface (Id);
5246 if Present (Generic_Parent_Type (N))
5248 (Nkind (Parent (Generic_Parent_Type (N))) /=
5249 N_Formal_Type_Declaration
5250 or else Nkind (Formal_Type_Definition
5251 (Parent (Generic_Parent_Type (N)))) /=
5252 N_Formal_Private_Type_Definition)
5254 if Is_Tagged_Type (Id) then
5256 -- If this is a generic actual subtype for a synchronized type,
5257 -- the primitive operations are those of the corresponding record
5258 -- for which there is a separate subtype declaration.
5260 if Is_Concurrent_Type (Id) then
5262 elsif Is_Class_Wide_Type (Id) then
5263 Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T));
5265 Derive_Subprograms (Generic_Parent_Type (N), Id, T);
5268 elsif Scope (Etype (Id)) /= Standard_Standard then
5269 Derive_Subprograms (Generic_Parent_Type (N), Id);
5273 if Is_Private_Type (T) and then Present (Full_View (T)) then
5274 Conditional_Delay (Id, Full_View (T));
5276 -- The subtypes of components or subcomponents of protected types
5277 -- do not need freeze nodes, which would otherwise appear in the
5278 -- wrong scope (before the freeze node for the protected type). The
5279 -- proper subtypes are those of the subcomponents of the corresponding
5282 elsif Ekind (Scope (Id)) /= E_Protected_Type
5283 and then Present (Scope (Scope (Id))) -- error defense
5284 and then Ekind (Scope (Scope (Id))) /= E_Protected_Type
5286 Conditional_Delay (Id, T);
5289 -- Check that Constraint_Error is raised for a scalar subtype indication
5290 -- when the lower or upper bound of a non-null range lies outside the
5291 -- range of the type mark.
5293 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5294 if Is_Scalar_Type (Etype (Id))
5295 and then Scalar_Range (Id) /=
5296 Scalar_Range (Etype (Subtype_Mark
5297 (Subtype_Indication (N))))
5301 Etype (Subtype_Mark (Subtype_Indication (N))));
5303 -- In the array case, check compatibility for each index
5305 elsif Is_Array_Type (Etype (Id)) and then Present (First_Index (Id))
5307 -- This really should be a subprogram that finds the indications
5311 Subt_Index : Node_Id := First_Index (Id);
5312 Target_Index : Node_Id :=
5314 (Subtype_Mark (Subtype_Indication (N))));
5315 Has_Dyn_Chk : Boolean := Has_Dynamic_Range_Check (N);
5318 while Present (Subt_Index) loop
5319 if ((Nkind (Subt_Index) = N_Identifier
5320 and then Ekind (Entity (Subt_Index)) in Scalar_Kind)
5321 or else Nkind (Subt_Index) = N_Subtype_Indication)
5323 Nkind (Scalar_Range (Etype (Subt_Index))) = N_Range
5326 Target_Typ : constant Entity_Id :=
5327 Etype (Target_Index);
5331 (Scalar_Range (Etype (Subt_Index)),
5334 Defining_Identifier (N));
5336 -- Reset Has_Dynamic_Range_Check on the subtype to
5337 -- prevent elision of the index check due to a dynamic
5338 -- check generated for a preceding index (needed since
5339 -- Insert_Range_Checks tries to avoid generating
5340 -- redundant checks on a given declaration).
5342 Set_Has_Dynamic_Range_Check (N, False);
5348 Sloc (Defining_Identifier (N)));
5350 -- Record whether this index involved a dynamic check
5353 Has_Dyn_Chk or else Has_Dynamic_Range_Check (N);
5357 Next_Index (Subt_Index);
5358 Next_Index (Target_Index);
5361 -- Finally, mark whether the subtype involves dynamic checks
5363 Set_Has_Dynamic_Range_Check (N, Has_Dyn_Chk);
5368 -- A type invariant applies to any subtype in its scope, in particular
5369 -- to a generic actual.
5371 if Has_Invariants (T) and then In_Open_Scopes (Scope (T)) then
5372 Set_Has_Invariants (Id);
5373 Set_Invariant_Procedure (Id, Invariant_Procedure (T));
5376 -- Make sure that generic actual types are properly frozen. The subtype
5377 -- is marked as a generic actual type when the enclosing instance is
5378 -- analyzed, so here we identify the subtype from the tree structure.
5381 and then Is_Generic_Actual_Type (Id)
5382 and then In_Instance
5383 and then not Comes_From_Source (N)
5384 and then Nkind (Subtype_Indication (N)) /= N_Subtype_Indication
5385 and then Is_Frozen (T)
5387 Freeze_Before (N, Id);
5390 Set_Optimize_Alignment_Flags (Id);
5391 Check_Eliminated (Id);
5394 if Has_Aspects (N) then
5395 Analyze_Aspect_Specifications (N, Id);
5398 Analyze_Dimension (N);
5399 end Analyze_Subtype_Declaration;
5401 --------------------------------
5402 -- Analyze_Subtype_Indication --
5403 --------------------------------
5405 procedure Analyze_Subtype_Indication (N : Node_Id) is
5406 T : constant Entity_Id := Subtype_Mark (N);
5407 R : constant Node_Id := Range_Expression (Constraint (N));
5414 Set_Etype (N, Etype (R));
5415 Resolve (R, Entity (T));
5417 Set_Error_Posted (R);
5418 Set_Error_Posted (T);
5420 end Analyze_Subtype_Indication;
5422 --------------------------
5423 -- Analyze_Variant_Part --
5424 --------------------------
5426 procedure Analyze_Variant_Part (N : Node_Id) is
5427 Discr_Name : Node_Id;
5428 Discr_Type : Entity_Id;
5430 procedure Process_Variant (A : Node_Id);
5431 -- Analyze declarations for a single variant
5433 package Analyze_Variant_Choices is
5434 new Generic_Analyze_Choices (Process_Variant);
5435 use Analyze_Variant_Choices;
5437 ---------------------
5438 -- Process_Variant --
5439 ---------------------
5441 procedure Process_Variant (A : Node_Id) is
5442 CL : constant Node_Id := Component_List (A);
5444 if not Null_Present (CL) then
5445 Analyze_Declarations (Component_Items (CL));
5447 if Present (Variant_Part (CL)) then
5448 Analyze (Variant_Part (CL));
5451 end Process_Variant;
5453 -- Start of processing for Analyze_Variant_Part
5456 Discr_Name := Name (N);
5457 Analyze (Discr_Name);
5459 -- If Discr_Name bad, get out (prevent cascaded errors)
5461 if Etype (Discr_Name) = Any_Type then
5465 -- Check invalid discriminant in variant part
5467 if Ekind (Entity (Discr_Name)) /= E_Discriminant then
5468 Error_Msg_N ("invalid discriminant name in variant part", Discr_Name);
5471 Discr_Type := Etype (Entity (Discr_Name));
5473 if not Is_Discrete_Type (Discr_Type) then
5475 ("discriminant in a variant part must be of a discrete type",
5480 -- Now analyze the choices, which also analyzes the declarations that
5481 -- are associated with each choice.
5483 Analyze_Choices (Variants (N), Discr_Type);
5485 -- Note: we used to instantiate and call Check_Choices here to check
5486 -- that the choices covered the discriminant, but it's too early to do
5487 -- that because of statically predicated subtypes, whose analysis may
5488 -- be deferred to their freeze point which may be as late as the freeze
5489 -- point of the containing record. So this call is now to be found in
5490 -- Freeze_Record_Declaration.
5492 end Analyze_Variant_Part;
5494 ----------------------------
5495 -- Array_Type_Declaration --
5496 ----------------------------
5498 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is
5499 Component_Def : constant Node_Id := Component_Definition (Def);
5500 Component_Typ : constant Node_Id := Subtype_Indication (Component_Def);
5501 Element_Type : Entity_Id;
5502 Implicit_Base : Entity_Id;
5504 Related_Id : Entity_Id := Empty;
5506 P : constant Node_Id := Parent (Def);
5510 if Nkind (Def) = N_Constrained_Array_Definition then
5511 Index := First (Discrete_Subtype_Definitions (Def));
5513 Index := First (Subtype_Marks (Def));
5516 -- Find proper names for the implicit types which may be public. In case
5517 -- of anonymous arrays we use the name of the first object of that type
5521 Related_Id := Defining_Identifier (P);
5527 while Present (Index) loop
5530 -- Test for odd case of trying to index a type by the type itself
5532 if Is_Entity_Name (Index) and then Entity (Index) = T then
5533 Error_Msg_N ("type& cannot be indexed by itself", Index);
5534 Set_Entity (Index, Standard_Boolean);
5535 Set_Etype (Index, Standard_Boolean);
5538 -- Check SPARK restriction requiring a subtype mark
5540 if not Nkind_In (Index, N_Identifier, N_Expanded_Name) then
5541 Check_SPARK_05_Restriction ("subtype mark required", Index);
5544 -- Add a subtype declaration for each index of private array type
5545 -- declaration whose etype is also private. For example:
5548 -- type Index is private;
5550 -- type Table is array (Index) of ...
5553 -- This is currently required by the expander for the internally
5554 -- generated equality subprogram of records with variant parts in
5555 -- which the etype of some component is such private type.
5557 if Ekind (Current_Scope) = E_Package
5558 and then In_Private_Part (Current_Scope)
5559 and then Has_Private_Declaration (Etype (Index))
5562 Loc : constant Source_Ptr := Sloc (Def);
5567 New_E := Make_Temporary (Loc, 'T');
5568 Set_Is_Internal (New_E);
5571 Make_Subtype_Declaration (Loc,
5572 Defining_Identifier => New_E,
5573 Subtype_Indication =>
5574 New_Occurrence_Of (Etype (Index), Loc));
5576 Insert_Before (Parent (Def), Decl);
5578 Set_Etype (Index, New_E);
5580 -- If the index is a range the Entity attribute is not
5581 -- available. Example:
5584 -- type T is private;
5586 -- type T is new Natural;
5587 -- Table : array (T(1) .. T(10)) of Boolean;
5590 if Nkind (Index) /= N_Range then
5591 Set_Entity (Index, New_E);
5596 Make_Index (Index, P, Related_Id, Nb_Index);
5598 -- Check error of subtype with predicate for index type
5600 Bad_Predicated_Subtype_Use
5601 ("subtype& has predicate, not allowed as index subtype",
5602 Index, Etype (Index));
5604 -- Move to next index
5607 Nb_Index := Nb_Index + 1;
5610 -- Process subtype indication if one is present
5612 if Present (Component_Typ) then
5613 Element_Type := Process_Subtype (Component_Typ, P, Related_Id, 'C');
5615 Set_Etype (Component_Typ, Element_Type);
5617 if not Nkind_In (Component_Typ, N_Identifier, N_Expanded_Name) then
5618 Check_SPARK_05_Restriction
5619 ("subtype mark required", Component_Typ);
5622 -- Ada 2005 (AI-230): Access Definition case
5624 else pragma Assert (Present (Access_Definition (Component_Def)));
5626 -- Indicate that the anonymous access type is created by the
5627 -- array type declaration.
5629 Element_Type := Access_Definition
5631 N => Access_Definition (Component_Def));
5632 Set_Is_Local_Anonymous_Access (Element_Type);
5634 -- Propagate the parent. This field is needed if we have to generate
5635 -- the master_id associated with an anonymous access to task type
5636 -- component (see Expand_N_Full_Type_Declaration.Build_Master)
5638 Set_Parent (Element_Type, Parent (T));
5640 -- Ada 2005 (AI-230): In case of components that are anonymous access
5641 -- types the level of accessibility depends on the enclosing type
5644 Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230)
5646 -- Ada 2005 (AI-254)
5649 CD : constant Node_Id :=
5650 Access_To_Subprogram_Definition
5651 (Access_Definition (Component_Def));
5653 if Present (CD) and then Protected_Present (CD) then
5655 Replace_Anonymous_Access_To_Protected_Subprogram (Def);
5660 -- Constrained array case
5663 T := Create_Itype (E_Void, P, Related_Id, 'T');
5666 if Nkind (Def) = N_Constrained_Array_Definition then
5668 -- Establish Implicit_Base as unconstrained base type
5670 Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B');
5672 Set_Etype (Implicit_Base, Implicit_Base);
5673 Set_Scope (Implicit_Base, Current_Scope);
5674 Set_Has_Delayed_Freeze (Implicit_Base);
5675 Set_Default_SSO (Implicit_Base);
5677 -- The constrained array type is a subtype of the unconstrained one
5679 Set_Ekind (T, E_Array_Subtype);
5680 Init_Size_Align (T);
5681 Set_Etype (T, Implicit_Base);
5682 Set_Scope (T, Current_Scope);
5683 Set_Is_Constrained (T);
5685 First (Discrete_Subtype_Definitions (Def)));
5686 Set_Has_Delayed_Freeze (T);
5688 -- Complete setup of implicit base type
5690 Set_First_Index (Implicit_Base, First_Index (T));
5691 Set_Component_Type (Implicit_Base, Element_Type);
5692 Set_Has_Task (Implicit_Base, Has_Task (Element_Type));
5693 Set_Has_Protected (Implicit_Base, Has_Protected (Element_Type));
5694 Set_Component_Size (Implicit_Base, Uint_0);
5695 Set_Packed_Array_Impl_Type (Implicit_Base, Empty);
5696 Set_Has_Controlled_Component (Implicit_Base,
5697 Has_Controlled_Component (Element_Type)
5698 or else Is_Controlled_Active (Element_Type));
5699 Set_Finalize_Storage_Only (Implicit_Base,
5700 Finalize_Storage_Only (Element_Type));
5702 -- Inherit the "ghostness" from the constrained array type
5704 if Is_Ghost_Entity (T) or else Ghost_Mode > None then
5705 Set_Is_Ghost_Entity (Implicit_Base);
5708 -- Unconstrained array case
5711 Set_Ekind (T, E_Array_Type);
5712 Init_Size_Align (T);
5714 Set_Scope (T, Current_Scope);
5715 Set_Component_Size (T, Uint_0);
5716 Set_Is_Constrained (T, False);
5717 Set_First_Index (T, First (Subtype_Marks (Def)));
5718 Set_Has_Delayed_Freeze (T, True);
5719 Set_Has_Task (T, Has_Task (Element_Type));
5720 Set_Has_Protected (T, Has_Protected (Element_Type));
5721 Set_Has_Controlled_Component (T, Has_Controlled_Component
5724 Is_Controlled_Active (Element_Type));
5725 Set_Finalize_Storage_Only (T, Finalize_Storage_Only
5727 Set_Default_SSO (T);
5730 -- Common attributes for both cases
5732 Set_Component_Type (Base_Type (T), Element_Type);
5733 Set_Packed_Array_Impl_Type (T, Empty);
5735 if Aliased_Present (Component_Definition (Def)) then
5736 Check_SPARK_05_Restriction
5737 ("aliased is not allowed", Component_Definition (Def));
5738 Set_Has_Aliased_Components (Etype (T));
5741 -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the
5742 -- array type to ensure that objects of this type are initialized.
5744 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (Element_Type) then
5745 Set_Can_Never_Be_Null (T);
5747 if Null_Exclusion_Present (Component_Definition (Def))
5749 -- No need to check itypes because in their case this check was
5750 -- done at their point of creation
5752 and then not Is_Itype (Element_Type)
5755 ("`NOT NULL` not allowed (null already excluded)",
5756 Subtype_Indication (Component_Definition (Def)));
5760 Priv := Private_Component (Element_Type);
5762 if Present (Priv) then
5764 -- Check for circular definitions
5766 if Priv = Any_Type then
5767 Set_Component_Type (Etype (T), Any_Type);
5769 -- There is a gap in the visibility of operations on the composite
5770 -- type only if the component type is defined in a different scope.
5772 elsif Scope (Priv) = Current_Scope then
5775 elsif Is_Limited_Type (Priv) then
5776 Set_Is_Limited_Composite (Etype (T));
5777 Set_Is_Limited_Composite (T);
5779 Set_Is_Private_Composite (Etype (T));
5780 Set_Is_Private_Composite (T);
5784 -- A syntax error in the declaration itself may lead to an empty index
5785 -- list, in which case do a minimal patch.
5787 if No (First_Index (T)) then
5788 Error_Msg_N ("missing index definition in array type declaration", T);
5791 Indexes : constant List_Id :=
5792 New_List (New_Occurrence_Of (Any_Id, Sloc (T)));
5794 Set_Discrete_Subtype_Definitions (Def, Indexes);
5795 Set_First_Index (T, First (Indexes));
5800 -- Create a concatenation operator for the new type. Internal array
5801 -- types created for packed entities do not need such, they are
5802 -- compatible with the user-defined type.
5804 if Number_Dimensions (T) = 1
5805 and then not Is_Packed_Array_Impl_Type (T)
5807 New_Concatenation_Op (T);
5810 -- In the case of an unconstrained array the parser has already verified
5811 -- that all the indexes are unconstrained but we still need to make sure
5812 -- that the element type is constrained.
5814 if not Is_Definite_Subtype (Element_Type) then
5816 ("unconstrained element type in array declaration",
5817 Subtype_Indication (Component_Def));
5819 elsif Is_Abstract_Type (Element_Type) then
5821 ("the type of a component cannot be abstract",
5822 Subtype_Indication (Component_Def));
5825 -- There may be an invariant declared for the component type, but
5826 -- the construction of the component invariant checking procedure
5827 -- takes place during expansion.
5828 end Array_Type_Declaration;
5830 ------------------------------------------------------
5831 -- Replace_Anonymous_Access_To_Protected_Subprogram --
5832 ------------------------------------------------------
5834 function Replace_Anonymous_Access_To_Protected_Subprogram
5835 (N : Node_Id) return Entity_Id
5837 Loc : constant Source_Ptr := Sloc (N);
5839 Curr_Scope : constant Scope_Stack_Entry :=
5840 Scope_Stack.Table (Scope_Stack.Last);
5842 Anon : constant Entity_Id := Make_Temporary (Loc, 'S');
5845 -- Access definition in declaration
5848 -- Object definition or formal definition with an access definition
5851 -- Declaration of anonymous access to subprogram type
5854 -- Original specification in access to subprogram
5859 Set_Is_Internal (Anon);
5862 when N_Component_Declaration |
5863 N_Unconstrained_Array_Definition |
5864 N_Constrained_Array_Definition =>
5865 Comp := Component_Definition (N);
5866 Acc := Access_Definition (Comp);
5868 when N_Discriminant_Specification =>
5869 Comp := Discriminant_Type (N);
5872 when N_Parameter_Specification =>
5873 Comp := Parameter_Type (N);
5876 when N_Access_Function_Definition =>
5877 Comp := Result_Definition (N);
5880 when N_Object_Declaration =>
5881 Comp := Object_Definition (N);
5884 when N_Function_Specification =>
5885 Comp := Result_Definition (N);
5889 raise Program_Error;
5892 Spec := Access_To_Subprogram_Definition (Acc);
5895 Make_Full_Type_Declaration (Loc,
5896 Defining_Identifier => Anon,
5897 Type_Definition => Copy_Separate_Tree (Spec));
5899 Mark_Rewrite_Insertion (Decl);
5901 -- In ASIS mode, analyze the profile on the original node, because
5902 -- the separate copy does not provide enough links to recover the
5903 -- original tree. Analysis is limited to type annotations, within
5904 -- a temporary scope that serves as an anonymous subprogram to collect
5905 -- otherwise useless temporaries and itypes.
5909 Typ : constant Entity_Id := Make_Temporary (Loc, 'S');
5912 if Nkind (Spec) = N_Access_Function_Definition then
5913 Set_Ekind (Typ, E_Function);
5915 Set_Ekind (Typ, E_Procedure);
5918 Set_Parent (Typ, N);
5919 Set_Scope (Typ, Current_Scope);
5922 -- Nothing to do if procedure is parameterless
5924 if Present (Parameter_Specifications (Spec)) then
5925 Process_Formals (Parameter_Specifications (Spec), Spec);
5928 if Nkind (Spec) = N_Access_Function_Definition then
5930 Def : constant Node_Id := Result_Definition (Spec);
5933 -- The result might itself be an anonymous access type, so
5936 if Nkind (Def) = N_Access_Definition then
5937 if Present (Access_To_Subprogram_Definition (Def)) then
5940 Replace_Anonymous_Access_To_Protected_Subprogram
5943 Find_Type (Subtype_Mark (Def));
5956 -- Insert the new declaration in the nearest enclosing scope. If the
5957 -- node is a body and N is its return type, the declaration belongs in
5958 -- the enclosing scope.
5962 if Nkind (P) = N_Subprogram_Body
5963 and then Nkind (N) = N_Function_Specification
5968 while Present (P) and then not Has_Declarations (P) loop
5972 pragma Assert (Present (P));
5974 if Nkind (P) = N_Package_Specification then
5975 Prepend (Decl, Visible_Declarations (P));
5977 Prepend (Decl, Declarations (P));
5980 -- Replace the anonymous type with an occurrence of the new declaration.
5981 -- In all cases the rewritten node does not have the null-exclusion
5982 -- attribute because (if present) it was already inherited by the
5983 -- anonymous entity (Anon). Thus, in case of components we do not
5984 -- inherit this attribute.
5986 if Nkind (N) = N_Parameter_Specification then
5987 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5988 Set_Etype (Defining_Identifier (N), Anon);
5989 Set_Null_Exclusion_Present (N, False);
5991 elsif Nkind (N) = N_Object_Declaration then
5992 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5993 Set_Etype (Defining_Identifier (N), Anon);
5995 elsif Nkind (N) = N_Access_Function_Definition then
5996 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5998 elsif Nkind (N) = N_Function_Specification then
5999 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
6000 Set_Etype (Defining_Unit_Name (N), Anon);
6004 Make_Component_Definition (Loc,
6005 Subtype_Indication => New_Occurrence_Of (Anon, Loc)));
6008 Mark_Rewrite_Insertion (Comp);
6010 if Nkind_In (N, N_Object_Declaration, N_Access_Function_Definition)
6011 or else (Nkind (Parent (N)) = N_Full_Type_Declaration
6012 and then not Is_Type (Current_Scope))
6015 -- Declaration can be analyzed in the current scope.
6020 -- Temporarily remove the current scope (record or subprogram) from
6021 -- the stack to add the new declarations to the enclosing scope.
6022 -- The anonymous entity is an Itype with the proper attributes.
6024 Scope_Stack.Decrement_Last;
6026 Set_Is_Itype (Anon);
6027 Set_Associated_Node_For_Itype (Anon, N);
6028 Scope_Stack.Append (Curr_Scope);
6031 Set_Ekind (Anon, E_Anonymous_Access_Protected_Subprogram_Type);
6032 Set_Can_Use_Internal_Rep (Anon, not Always_Compatible_Rep_On_Target);
6034 end Replace_Anonymous_Access_To_Protected_Subprogram;
6036 -------------------------------
6037 -- Build_Derived_Access_Type --
6038 -------------------------------
6040 procedure Build_Derived_Access_Type
6042 Parent_Type : Entity_Id;
6043 Derived_Type : Entity_Id)
6045 S : constant Node_Id := Subtype_Indication (Type_Definition (N));
6047 Desig_Type : Entity_Id;
6049 Discr_Con_Elist : Elist_Id;
6050 Discr_Con_El : Elmt_Id;
6054 -- Set the designated type so it is available in case this is an access
6055 -- to a self-referential type, e.g. a standard list type with a next
6056 -- pointer. Will be reset after subtype is built.
6058 Set_Directly_Designated_Type
6059 (Derived_Type, Designated_Type (Parent_Type));
6061 Subt := Process_Subtype (S, N);
6063 if Nkind (S) /= N_Subtype_Indication
6064 and then Subt /= Base_Type (Subt)
6066 Set_Ekind (Derived_Type, E_Access_Subtype);
6069 if Ekind (Derived_Type) = E_Access_Subtype then
6071 Pbase : constant Entity_Id := Base_Type (Parent_Type);
6072 Ibase : constant Entity_Id :=
6073 Create_Itype (Ekind (Pbase), N, Derived_Type, 'B');
6074 Svg_Chars : constant Name_Id := Chars (Ibase);
6075 Svg_Next_E : constant Entity_Id := Next_Entity (Ibase);
6078 Copy_Node (Pbase, Ibase);
6080 Set_Chars (Ibase, Svg_Chars);
6081 Set_Next_Entity (Ibase, Svg_Next_E);
6082 Set_Sloc (Ibase, Sloc (Derived_Type));
6083 Set_Scope (Ibase, Scope (Derived_Type));
6084 Set_Freeze_Node (Ibase, Empty);
6085 Set_Is_Frozen (Ibase, False);
6086 Set_Comes_From_Source (Ibase, False);
6087 Set_Is_First_Subtype (Ibase, False);
6089 Set_Etype (Ibase, Pbase);
6090 Set_Etype (Derived_Type, Ibase);
6094 Set_Directly_Designated_Type
6095 (Derived_Type, Designated_Type (Subt));
6097 Set_Is_Constrained (Derived_Type, Is_Constrained (Subt));
6098 Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type));
6099 Set_Size_Info (Derived_Type, Parent_Type);
6100 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
6101 Set_Depends_On_Private (Derived_Type,
6102 Has_Private_Component (Derived_Type));
6103 Conditional_Delay (Derived_Type, Subt);
6105 -- Ada 2005 (AI-231): Set the null-exclusion attribute, and verify
6106 -- that it is not redundant.
6108 if Null_Exclusion_Present (Type_Definition (N)) then
6109 Set_Can_Never_Be_Null (Derived_Type);
6111 -- What is with the "AND THEN FALSE" here ???
6113 if Can_Never_Be_Null (Parent_Type)
6117 ("`NOT NULL` not allowed (& already excludes null)",
6121 elsif Can_Never_Be_Null (Parent_Type) then
6122 Set_Can_Never_Be_Null (Derived_Type);
6125 -- Note: we do not copy the Storage_Size_Variable, since we always go to
6126 -- the root type for this information.
6128 -- Apply range checks to discriminants for derived record case
6129 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
6131 Desig_Type := Designated_Type (Derived_Type);
6132 if Is_Composite_Type (Desig_Type)
6133 and then (not Is_Array_Type (Desig_Type))
6134 and then Has_Discriminants (Desig_Type)
6135 and then Base_Type (Desig_Type) /= Desig_Type
6137 Discr_Con_Elist := Discriminant_Constraint (Desig_Type);
6138 Discr_Con_El := First_Elmt (Discr_Con_Elist);
6140 Discr := First_Discriminant (Base_Type (Desig_Type));
6141 while Present (Discr_Con_El) loop
6142 Apply_Range_Check (Node (Discr_Con_El), Etype (Discr));
6143 Next_Elmt (Discr_Con_El);
6144 Next_Discriminant (Discr);
6147 end Build_Derived_Access_Type;
6149 ------------------------------
6150 -- Build_Derived_Array_Type --
6151 ------------------------------
6153 procedure Build_Derived_Array_Type
6155 Parent_Type : Entity_Id;
6156 Derived_Type : Entity_Id)
6158 Loc : constant Source_Ptr := Sloc (N);
6159 Tdef : constant Node_Id := Type_Definition (N);
6160 Indic : constant Node_Id := Subtype_Indication (Tdef);
6161 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
6162 Implicit_Base : Entity_Id;
6163 New_Indic : Node_Id;
6165 procedure Make_Implicit_Base;
6166 -- If the parent subtype is constrained, the derived type is a subtype
6167 -- of an implicit base type derived from the parent base.
6169 ------------------------
6170 -- Make_Implicit_Base --
6171 ------------------------
6173 procedure Make_Implicit_Base is
6176 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
6178 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
6179 Set_Etype (Implicit_Base, Parent_Base);
6181 Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base);
6182 Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base);
6184 Set_Has_Delayed_Freeze (Implicit_Base, True);
6186 -- Inherit the "ghostness" from the parent base type
6188 if Is_Ghost_Entity (Parent_Base) or else Ghost_Mode > None then
6189 Set_Is_Ghost_Entity (Implicit_Base);
6191 end Make_Implicit_Base;
6193 -- Start of processing for Build_Derived_Array_Type
6196 if not Is_Constrained (Parent_Type) then
6197 if Nkind (Indic) /= N_Subtype_Indication then
6198 Set_Ekind (Derived_Type, E_Array_Type);
6200 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
6201 Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type);
6203 Set_Has_Delayed_Freeze (Derived_Type, True);
6207 Set_Etype (Derived_Type, Implicit_Base);
6210 Make_Subtype_Declaration (Loc,
6211 Defining_Identifier => Derived_Type,
6212 Subtype_Indication =>
6213 Make_Subtype_Indication (Loc,
6214 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6215 Constraint => Constraint (Indic)));
6217 Rewrite (N, New_Indic);
6222 if Nkind (Indic) /= N_Subtype_Indication then
6225 Set_Ekind (Derived_Type, Ekind (Parent_Type));
6226 Set_Etype (Derived_Type, Implicit_Base);
6227 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
6230 Error_Msg_N ("illegal constraint on constrained type", Indic);
6234 -- If parent type is not a derived type itself, and is declared in
6235 -- closed scope (e.g. a subprogram), then we must explicitly introduce
6236 -- the new type's concatenation operator since Derive_Subprograms
6237 -- will not inherit the parent's operator. If the parent type is
6238 -- unconstrained, the operator is of the unconstrained base type.
6240 if Number_Dimensions (Parent_Type) = 1
6241 and then not Is_Limited_Type (Parent_Type)
6242 and then not Is_Derived_Type (Parent_Type)
6243 and then not Is_Package_Or_Generic_Package
6244 (Scope (Base_Type (Parent_Type)))
6246 if not Is_Constrained (Parent_Type)
6247 and then Is_Constrained (Derived_Type)
6249 New_Concatenation_Op (Implicit_Base);
6251 New_Concatenation_Op (Derived_Type);
6254 end Build_Derived_Array_Type;
6256 -----------------------------------
6257 -- Build_Derived_Concurrent_Type --
6258 -----------------------------------
6260 procedure Build_Derived_Concurrent_Type
6262 Parent_Type : Entity_Id;
6263 Derived_Type : Entity_Id)
6265 Loc : constant Source_Ptr := Sloc (N);
6267 Corr_Record : constant Entity_Id := Make_Temporary (Loc, 'C');
6268 Corr_Decl : Node_Id;
6269 Corr_Decl_Needed : Boolean;
6270 -- If the derived type has fewer discriminants than its parent, the
6271 -- corresponding record is also a derived type, in order to account for
6272 -- the bound discriminants. We create a full type declaration for it in
6275 Constraint_Present : constant Boolean :=
6276 Nkind (Subtype_Indication (Type_Definition (N))) =
6277 N_Subtype_Indication;
6279 D_Constraint : Node_Id;
6280 New_Constraint : Elist_Id;
6281 Old_Disc : Entity_Id;
6282 New_Disc : Entity_Id;
6286 Set_Stored_Constraint (Derived_Type, No_Elist);
6287 Corr_Decl_Needed := False;
6290 if Present (Discriminant_Specifications (N))
6291 and then Constraint_Present
6293 Old_Disc := First_Discriminant (Parent_Type);
6294 New_Disc := First (Discriminant_Specifications (N));
6295 while Present (New_Disc) and then Present (Old_Disc) loop
6296 Next_Discriminant (Old_Disc);
6301 if Present (Old_Disc) and then Expander_Active then
6303 -- The new type has fewer discriminants, so we need to create a new
6304 -- corresponding record, which is derived from the corresponding
6305 -- record of the parent, and has a stored constraint that captures
6306 -- the values of the discriminant constraints. The corresponding
6307 -- record is needed only if expander is active and code generation is
6310 -- The type declaration for the derived corresponding record has the
6311 -- same discriminant part and constraints as the current declaration.
6312 -- Copy the unanalyzed tree to build declaration.
6314 Corr_Decl_Needed := True;
6315 New_N := Copy_Separate_Tree (N);
6318 Make_Full_Type_Declaration (Loc,
6319 Defining_Identifier => Corr_Record,
6320 Discriminant_Specifications =>
6321 Discriminant_Specifications (New_N),
6323 Make_Derived_Type_Definition (Loc,
6324 Subtype_Indication =>
6325 Make_Subtype_Indication (Loc,
6328 (Corresponding_Record_Type (Parent_Type), Loc),
6331 (Subtype_Indication (Type_Definition (New_N))))));
6334 -- Copy Storage_Size and Relative_Deadline variables if task case
6336 if Is_Task_Type (Parent_Type) then
6337 Set_Storage_Size_Variable (Derived_Type,
6338 Storage_Size_Variable (Parent_Type));
6339 Set_Relative_Deadline_Variable (Derived_Type,
6340 Relative_Deadline_Variable (Parent_Type));
6343 if Present (Discriminant_Specifications (N)) then
6344 Push_Scope (Derived_Type);
6345 Check_Or_Process_Discriminants (N, Derived_Type);
6347 if Constraint_Present then
6349 Expand_To_Stored_Constraint
6351 Build_Discriminant_Constraints
6353 Subtype_Indication (Type_Definition (N)), True));
6358 elsif Constraint_Present then
6360 -- Build constrained subtype, copying the constraint, and derive
6361 -- from it to create a derived constrained type.
6364 Loc : constant Source_Ptr := Sloc (N);
6365 Anon : constant Entity_Id :=
6366 Make_Defining_Identifier (Loc,
6367 Chars => New_External_Name (Chars (Derived_Type), 'T'));
6372 Make_Subtype_Declaration (Loc,
6373 Defining_Identifier => Anon,
6374 Subtype_Indication =>
6375 New_Copy_Tree (Subtype_Indication (Type_Definition (N))));
6376 Insert_Before (N, Decl);
6379 Rewrite (Subtype_Indication (Type_Definition (N)),
6380 New_Occurrence_Of (Anon, Loc));
6381 Set_Analyzed (Derived_Type, False);
6387 -- By default, operations and private data are inherited from parent.
6388 -- However, in the presence of bound discriminants, a new corresponding
6389 -- record will be created, see below.
6391 Set_Has_Discriminants
6392 (Derived_Type, Has_Discriminants (Parent_Type));
6393 Set_Corresponding_Record_Type
6394 (Derived_Type, Corresponding_Record_Type (Parent_Type));
6396 -- Is_Constrained is set according the parent subtype, but is set to
6397 -- False if the derived type is declared with new discriminants.
6401 (Is_Constrained (Parent_Type) or else Constraint_Present)
6402 and then not Present (Discriminant_Specifications (N)));
6404 if Constraint_Present then
6405 if not Has_Discriminants (Parent_Type) then
6406 Error_Msg_N ("untagged parent must have discriminants", N);
6408 elsif Present (Discriminant_Specifications (N)) then
6410 -- Verify that new discriminants are used to constrain old ones
6415 (Constraint (Subtype_Indication (Type_Definition (N)))));
6417 Old_Disc := First_Discriminant (Parent_Type);
6419 while Present (D_Constraint) loop
6420 if Nkind (D_Constraint) /= N_Discriminant_Association then
6422 -- Positional constraint. If it is a reference to a new
6423 -- discriminant, it constrains the corresponding old one.
6425 if Nkind (D_Constraint) = N_Identifier then
6426 New_Disc := First_Discriminant (Derived_Type);
6427 while Present (New_Disc) loop
6428 exit when Chars (New_Disc) = Chars (D_Constraint);
6429 Next_Discriminant (New_Disc);
6432 if Present (New_Disc) then
6433 Set_Corresponding_Discriminant (New_Disc, Old_Disc);
6437 Next_Discriminant (Old_Disc);
6439 -- if this is a named constraint, search by name for the old
6440 -- discriminants constrained by the new one.
6442 elsif Nkind (Expression (D_Constraint)) = N_Identifier then
6444 -- Find new discriminant with that name
6446 New_Disc := First_Discriminant (Derived_Type);
6447 while Present (New_Disc) loop
6449 Chars (New_Disc) = Chars (Expression (D_Constraint));
6450 Next_Discriminant (New_Disc);
6453 if Present (New_Disc) then
6455 -- Verify that new discriminant renames some discriminant
6456 -- of the parent type, and associate the new discriminant
6457 -- with one or more old ones that it renames.
6463 Selector := First (Selector_Names (D_Constraint));
6464 while Present (Selector) loop
6465 Old_Disc := First_Discriminant (Parent_Type);
6466 while Present (Old_Disc) loop
6467 exit when Chars (Old_Disc) = Chars (Selector);
6468 Next_Discriminant (Old_Disc);
6471 if Present (Old_Disc) then
6472 Set_Corresponding_Discriminant
6473 (New_Disc, Old_Disc);
6482 Next (D_Constraint);
6485 New_Disc := First_Discriminant (Derived_Type);
6486 while Present (New_Disc) loop
6487 if No (Corresponding_Discriminant (New_Disc)) then
6489 ("new discriminant& must constrain old one", N, New_Disc);
6492 Subtypes_Statically_Compatible
6494 Etype (Corresponding_Discriminant (New_Disc)))
6497 ("& not statically compatible with parent discriminant",
6501 Next_Discriminant (New_Disc);
6505 elsif Present (Discriminant_Specifications (N)) then
6507 ("missing discriminant constraint in untagged derivation", N);
6510 -- The entity chain of the derived type includes the new discriminants
6511 -- but shares operations with the parent.
6513 if Present (Discriminant_Specifications (N)) then
6514 Old_Disc := First_Discriminant (Parent_Type);
6515 while Present (Old_Disc) loop
6516 if No (Next_Entity (Old_Disc))
6517 or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant
6520 (Last_Entity (Derived_Type), Next_Entity (Old_Disc));
6524 Next_Discriminant (Old_Disc);
6528 Set_First_Entity (Derived_Type, First_Entity (Parent_Type));
6529 if Has_Discriminants (Parent_Type) then
6530 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6531 Set_Discriminant_Constraint (
6532 Derived_Type, Discriminant_Constraint (Parent_Type));
6536 Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type));
6538 Set_Has_Completion (Derived_Type);
6540 if Corr_Decl_Needed then
6541 Set_Stored_Constraint (Derived_Type, New_Constraint);
6542 Insert_After (N, Corr_Decl);
6543 Analyze (Corr_Decl);
6544 Set_Corresponding_Record_Type (Derived_Type, Corr_Record);
6546 end Build_Derived_Concurrent_Type;
6548 ------------------------------------
6549 -- Build_Derived_Enumeration_Type --
6550 ------------------------------------
6552 procedure Build_Derived_Enumeration_Type
6554 Parent_Type : Entity_Id;
6555 Derived_Type : Entity_Id)
6557 Loc : constant Source_Ptr := Sloc (N);
6558 Def : constant Node_Id := Type_Definition (N);
6559 Indic : constant Node_Id := Subtype_Indication (Def);
6560 Implicit_Base : Entity_Id;
6561 Literal : Entity_Id;
6562 New_Lit : Entity_Id;
6563 Literals_List : List_Id;
6564 Type_Decl : Node_Id;
6566 Rang_Expr : Node_Id;
6569 -- Since types Standard.Character and Standard.[Wide_]Wide_Character do
6570 -- not have explicit literals lists we need to process types derived
6571 -- from them specially. This is handled by Derived_Standard_Character.
6572 -- If the parent type is a generic type, there are no literals either,
6573 -- and we construct the same skeletal representation as for the generic
6576 if Is_Standard_Character_Type (Parent_Type) then
6577 Derived_Standard_Character (N, Parent_Type, Derived_Type);
6579 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
6585 if Nkind (Indic) /= N_Subtype_Indication then
6587 Make_Attribute_Reference (Loc,
6588 Attribute_Name => Name_First,
6589 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6590 Set_Etype (Lo, Derived_Type);
6593 Make_Attribute_Reference (Loc,
6594 Attribute_Name => Name_Last,
6595 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6596 Set_Etype (Hi, Derived_Type);
6598 Set_Scalar_Range (Derived_Type,
6604 -- Analyze subtype indication and verify compatibility
6605 -- with parent type.
6607 if Base_Type (Process_Subtype (Indic, N)) /=
6608 Base_Type (Parent_Type)
6611 ("illegal constraint for formal discrete type", N);
6617 -- If a constraint is present, analyze the bounds to catch
6618 -- premature usage of the derived literals.
6620 if Nkind (Indic) = N_Subtype_Indication
6621 and then Nkind (Range_Expression (Constraint (Indic))) = N_Range
6623 Analyze (Low_Bound (Range_Expression (Constraint (Indic))));
6624 Analyze (High_Bound (Range_Expression (Constraint (Indic))));
6627 -- Introduce an implicit base type for the derived type even if there
6628 -- is no constraint attached to it, since this seems closer to the
6629 -- Ada semantics. Build a full type declaration tree for the derived
6630 -- type using the implicit base type as the defining identifier. The
6631 -- build a subtype declaration tree which applies the constraint (if
6632 -- any) have it replace the derived type declaration.
6634 Literal := First_Literal (Parent_Type);
6635 Literals_List := New_List;
6636 while Present (Literal)
6637 and then Ekind (Literal) = E_Enumeration_Literal
6639 -- Literals of the derived type have the same representation as
6640 -- those of the parent type, but this representation can be
6641 -- overridden by an explicit representation clause. Indicate
6642 -- that there is no explicit representation given yet. These
6643 -- derived literals are implicit operations of the new type,
6644 -- and can be overridden by explicit ones.
6646 if Nkind (Literal) = N_Defining_Character_Literal then
6648 Make_Defining_Character_Literal (Loc, Chars (Literal));
6650 New_Lit := Make_Defining_Identifier (Loc, Chars (Literal));
6653 Set_Ekind (New_Lit, E_Enumeration_Literal);
6654 Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal));
6655 Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal));
6656 Set_Enumeration_Rep_Expr (New_Lit, Empty);
6657 Set_Alias (New_Lit, Literal);
6658 Set_Is_Known_Valid (New_Lit, True);
6660 Append (New_Lit, Literals_List);
6661 Next_Literal (Literal);
6665 Make_Defining_Identifier (Sloc (Derived_Type),
6666 Chars => New_External_Name (Chars (Derived_Type), 'B'));
6668 -- Indicate the proper nature of the derived type. This must be done
6669 -- before analysis of the literals, to recognize cases when a literal
6670 -- may be hidden by a previous explicit function definition (cf.
6673 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
6674 Set_Etype (Derived_Type, Implicit_Base);
6677 Make_Full_Type_Declaration (Loc,
6678 Defining_Identifier => Implicit_Base,
6679 Discriminant_Specifications => No_List,
6681 Make_Enumeration_Type_Definition (Loc, Literals_List));
6683 Mark_Rewrite_Insertion (Type_Decl);
6684 Insert_Before (N, Type_Decl);
6685 Analyze (Type_Decl);
6687 -- The anonymous base now has a full declaration, but this base
6688 -- is not a first subtype.
6690 Set_Is_First_Subtype (Implicit_Base, False);
6692 -- After the implicit base is analyzed its Etype needs to be changed
6693 -- to reflect the fact that it is derived from the parent type which
6694 -- was ignored during analysis. We also set the size at this point.
6696 Set_Etype (Implicit_Base, Parent_Type);
6698 Set_Size_Info (Implicit_Base, Parent_Type);
6699 Set_RM_Size (Implicit_Base, RM_Size (Parent_Type));
6700 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type));
6702 -- Copy other flags from parent type
6704 Set_Has_Non_Standard_Rep
6705 (Implicit_Base, Has_Non_Standard_Rep
6707 Set_Has_Pragma_Ordered
6708 (Implicit_Base, Has_Pragma_Ordered
6710 Set_Has_Delayed_Freeze (Implicit_Base);
6712 -- Process the subtype indication including a validation check on the
6713 -- constraint, if any. If a constraint is given, its bounds must be
6714 -- implicitly converted to the new type.
6716 if Nkind (Indic) = N_Subtype_Indication then
6718 R : constant Node_Id :=
6719 Range_Expression (Constraint (Indic));
6722 if Nkind (R) = N_Range then
6723 Hi := Build_Scalar_Bound
6724 (High_Bound (R), Parent_Type, Implicit_Base);
6725 Lo := Build_Scalar_Bound
6726 (Low_Bound (R), Parent_Type, Implicit_Base);
6729 -- Constraint is a Range attribute. Replace with explicit
6730 -- mention of the bounds of the prefix, which must be a
6733 Analyze (Prefix (R));
6735 Convert_To (Implicit_Base,
6736 Make_Attribute_Reference (Loc,
6737 Attribute_Name => Name_Last,
6739 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6742 Convert_To (Implicit_Base,
6743 Make_Attribute_Reference (Loc,
6744 Attribute_Name => Name_First,
6746 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6753 (Type_High_Bound (Parent_Type),
6754 Parent_Type, Implicit_Base);
6757 (Type_Low_Bound (Parent_Type),
6758 Parent_Type, Implicit_Base);
6766 -- If we constructed a default range for the case where no range
6767 -- was given, then the expressions in the range must not freeze
6768 -- since they do not correspond to expressions in the source.
6770 if Nkind (Indic) /= N_Subtype_Indication then
6771 Set_Must_Not_Freeze (Lo);
6772 Set_Must_Not_Freeze (Hi);
6773 Set_Must_Not_Freeze (Rang_Expr);
6777 Make_Subtype_Declaration (Loc,
6778 Defining_Identifier => Derived_Type,
6779 Subtype_Indication =>
6780 Make_Subtype_Indication (Loc,
6781 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6783 Make_Range_Constraint (Loc,
6784 Range_Expression => Rang_Expr))));
6788 -- Propagate the aspects from the original type declaration to the
6789 -- declaration of the implicit base.
6791 Move_Aspects (From => Original_Node (N), To => Type_Decl);
6793 -- Apply a range check. Since this range expression doesn't have an
6794 -- Etype, we have to specifically pass the Source_Typ parameter. Is
6797 if Nkind (Indic) = N_Subtype_Indication then
6799 (Range_Expression (Constraint (Indic)), Parent_Type,
6800 Source_Typ => Entity (Subtype_Mark (Indic)));
6803 end Build_Derived_Enumeration_Type;
6805 --------------------------------
6806 -- Build_Derived_Numeric_Type --
6807 --------------------------------
6809 procedure Build_Derived_Numeric_Type
6811 Parent_Type : Entity_Id;
6812 Derived_Type : Entity_Id)
6814 Loc : constant Source_Ptr := Sloc (N);
6815 Tdef : constant Node_Id := Type_Definition (N);
6816 Indic : constant Node_Id := Subtype_Indication (Tdef);
6817 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
6818 No_Constraint : constant Boolean := Nkind (Indic) /=
6819 N_Subtype_Indication;
6820 Implicit_Base : Entity_Id;
6826 -- Process the subtype indication including a validation check on
6827 -- the constraint if any.
6829 Discard_Node (Process_Subtype (Indic, N));
6831 -- Introduce an implicit base type for the derived type even if there
6832 -- is no constraint attached to it, since this seems closer to the Ada
6836 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
6838 Set_Etype (Implicit_Base, Parent_Base);
6839 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
6840 Set_Size_Info (Implicit_Base, Parent_Base);
6841 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base));
6842 Set_Parent (Implicit_Base, Parent (Derived_Type));
6843 Set_Is_Known_Valid (Implicit_Base, Is_Known_Valid (Parent_Base));
6845 -- Set RM Size for discrete type or decimal fixed-point type
6846 -- Ordinary fixed-point is excluded, why???
6848 if Is_Discrete_Type (Parent_Base)
6849 or else Is_Decimal_Fixed_Point_Type (Parent_Base)
6851 Set_RM_Size (Implicit_Base, RM_Size (Parent_Base));
6854 Set_Has_Delayed_Freeze (Implicit_Base);
6856 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
6857 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
6859 Set_Scalar_Range (Implicit_Base,
6864 if Has_Infinities (Parent_Base) then
6865 Set_Includes_Infinities (Scalar_Range (Implicit_Base));
6868 -- The Derived_Type, which is the entity of the declaration, is a
6869 -- subtype of the implicit base. Its Ekind is a subtype, even in the
6870 -- absence of an explicit constraint.
6872 Set_Etype (Derived_Type, Implicit_Base);
6874 -- If we did not have a constraint, then the Ekind is set from the
6875 -- parent type (otherwise Process_Subtype has set the bounds)
6877 if No_Constraint then
6878 Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type)));
6881 -- If we did not have a range constraint, then set the range from the
6882 -- parent type. Otherwise, the Process_Subtype call has set the bounds.
6884 if No_Constraint or else not Has_Range_Constraint (Indic) then
6885 Set_Scalar_Range (Derived_Type,
6887 Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)),
6888 High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type))));
6889 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6891 if Has_Infinities (Parent_Type) then
6892 Set_Includes_Infinities (Scalar_Range (Derived_Type));
6895 Set_Is_Known_Valid (Derived_Type, Is_Known_Valid (Parent_Type));
6898 Set_Is_Descendent_Of_Address (Derived_Type,
6899 Is_Descendent_Of_Address (Parent_Type));
6900 Set_Is_Descendent_Of_Address (Implicit_Base,
6901 Is_Descendent_Of_Address (Parent_Type));
6903 -- Set remaining type-specific fields, depending on numeric type
6905 if Is_Modular_Integer_Type (Parent_Type) then
6906 Set_Modulus (Implicit_Base, Modulus (Parent_Base));
6908 Set_Non_Binary_Modulus
6909 (Implicit_Base, Non_Binary_Modulus (Parent_Base));
6912 (Implicit_Base, Is_Known_Valid (Parent_Base));
6914 elsif Is_Floating_Point_Type (Parent_Type) then
6916 -- Digits of base type is always copied from the digits value of
6917 -- the parent base type, but the digits of the derived type will
6918 -- already have been set if there was a constraint present.
6920 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6921 Set_Float_Rep (Implicit_Base, Float_Rep (Parent_Base));
6923 if No_Constraint then
6924 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type));
6927 elsif Is_Fixed_Point_Type (Parent_Type) then
6929 -- Small of base type and derived type are always copied from the
6930 -- parent base type, since smalls never change. The delta of the
6931 -- base type is also copied from the parent base type. However the
6932 -- delta of the derived type will have been set already if a
6933 -- constraint was present.
6935 Set_Small_Value (Derived_Type, Small_Value (Parent_Base));
6936 Set_Small_Value (Implicit_Base, Small_Value (Parent_Base));
6937 Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base));
6939 if No_Constraint then
6940 Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type));
6943 -- The scale and machine radix in the decimal case are always
6944 -- copied from the parent base type.
6946 if Is_Decimal_Fixed_Point_Type (Parent_Type) then
6947 Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base));
6948 Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base));
6950 Set_Machine_Radix_10
6951 (Derived_Type, Machine_Radix_10 (Parent_Base));
6952 Set_Machine_Radix_10
6953 (Implicit_Base, Machine_Radix_10 (Parent_Base));
6955 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6957 if No_Constraint then
6958 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base));
6961 -- the analysis of the subtype_indication sets the
6962 -- digits value of the derived type.
6969 if Is_Integer_Type (Parent_Type) then
6970 Set_Has_Shift_Operator
6971 (Implicit_Base, Has_Shift_Operator (Parent_Type));
6974 -- The type of the bounds is that of the parent type, and they
6975 -- must be converted to the derived type.
6977 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
6979 -- The implicit_base should be frozen when the derived type is frozen,
6980 -- but note that it is used in the conversions of the bounds. For fixed
6981 -- types we delay the determination of the bounds until the proper
6982 -- freezing point. For other numeric types this is rejected by GCC, for
6983 -- reasons that are currently unclear (???), so we choose to freeze the
6984 -- implicit base now. In the case of integers and floating point types
6985 -- this is harmless because subsequent representation clauses cannot
6986 -- affect anything, but it is still baffling that we cannot use the
6987 -- same mechanism for all derived numeric types.
6989 -- There is a further complication: actually some representation
6990 -- clauses can affect the implicit base type. For example, attribute
6991 -- definition clauses for stream-oriented attributes need to set the
6992 -- corresponding TSS entries on the base type, and this normally
6993 -- cannot be done after the base type is frozen, so the circuitry in
6994 -- Sem_Ch13.New_Stream_Subprogram must account for this possibility
6995 -- and not use Set_TSS in this case.
6997 -- There are also consequences for the case of delayed representation
6998 -- aspects for some cases. For example, a Size aspect is delayed and
6999 -- should not be evaluated to the freeze point. This early freezing
7000 -- means that the size attribute evaluation happens too early???
7002 if Is_Fixed_Point_Type (Parent_Type) then
7003 Conditional_Delay (Implicit_Base, Parent_Type);
7005 Freeze_Before (N, Implicit_Base);
7007 end Build_Derived_Numeric_Type;
7009 --------------------------------
7010 -- Build_Derived_Private_Type --
7011 --------------------------------
7013 procedure Build_Derived_Private_Type
7015 Parent_Type : Entity_Id;
7016 Derived_Type : Entity_Id;
7017 Is_Completion : Boolean;
7018 Derive_Subps : Boolean := True)
7020 Loc : constant Source_Ptr := Sloc (N);
7021 Par_Base : constant Entity_Id := Base_Type (Parent_Type);
7022 Par_Scope : constant Entity_Id := Scope (Par_Base);
7023 Full_N : constant Node_Id := New_Copy_Tree (N);
7024 Full_Der : Entity_Id := New_Copy (Derived_Type);
7027 procedure Build_Full_Derivation;
7028 -- Build full derivation, i.e. derive from the full view
7030 procedure Copy_And_Build;
7031 -- Copy derived type declaration, replace parent with its full view,
7032 -- and build derivation
7034 ---------------------------
7035 -- Build_Full_Derivation --
7036 ---------------------------
7038 procedure Build_Full_Derivation is
7040 -- If parent scope is not open, install the declarations
7042 if not In_Open_Scopes (Par_Scope) then
7043 Install_Private_Declarations (Par_Scope);
7044 Install_Visible_Declarations (Par_Scope);
7046 Uninstall_Declarations (Par_Scope);
7048 -- If parent scope is open and in another unit, and parent has a
7049 -- completion, then the derivation is taking place in the visible
7050 -- part of a child unit. In that case retrieve the full view of
7051 -- the parent momentarily.
7053 elsif not In_Same_Source_Unit (N, Parent_Type) then
7054 Full_P := Full_View (Parent_Type);
7055 Exchange_Declarations (Parent_Type);
7057 Exchange_Declarations (Full_P);
7059 -- Otherwise it is a local derivation
7064 end Build_Full_Derivation;
7066 --------------------
7067 -- Copy_And_Build --
7068 --------------------
7070 procedure Copy_And_Build is
7071 Full_Parent : Entity_Id := Parent_Type;
7074 -- If the parent is itself derived from another private type,
7075 -- installing the private declarations has not affected its
7076 -- privacy status, so use its own full view explicitly.
7078 if Is_Private_Type (Full_Parent)
7079 and then Present (Full_View (Full_Parent))
7081 Full_Parent := Full_View (Full_Parent);
7084 -- And its underlying full view if necessary
7086 if Is_Private_Type (Full_Parent)
7087 and then Present (Underlying_Full_View (Full_Parent))
7089 Full_Parent := Underlying_Full_View (Full_Parent);
7092 -- For record, access and most enumeration types, derivation from
7093 -- the full view requires a fully-fledged declaration. In the other
7094 -- cases, just use an itype.
7096 if Ekind (Full_Parent) in Record_Kind
7097 or else Ekind (Full_Parent) in Access_Kind
7099 (Ekind (Full_Parent) in Enumeration_Kind
7100 and then not Is_Standard_Character_Type (Full_Parent)
7101 and then not Is_Generic_Type (Root_Type (Full_Parent)))
7103 -- Copy and adjust declaration to provide a completion for what
7104 -- is originally a private declaration. Indicate that full view
7105 -- is internally generated.
7107 Set_Comes_From_Source (Full_N, False);
7108 Set_Comes_From_Source (Full_Der, False);
7109 Set_Parent (Full_Der, Full_N);
7110 Set_Defining_Identifier (Full_N, Full_Der);
7112 -- If there are no constraints, adjust the subtype mark
7114 if Nkind (Subtype_Indication (Type_Definition (Full_N))) /=
7115 N_Subtype_Indication
7117 Set_Subtype_Indication
7118 (Type_Definition (Full_N),
7119 New_Occurrence_Of (Full_Parent, Sloc (Full_N)));
7122 Insert_After (N, Full_N);
7124 -- Build full view of derived type from full view of parent which
7125 -- is now installed. Subprograms have been derived on the partial
7126 -- view, the completion does not derive them anew.
7128 if Ekind (Full_Parent) in Record_Kind then
7130 -- If parent type is tagged, the completion inherits the proper
7131 -- primitive operations.
7133 if Is_Tagged_Type (Parent_Type) then
7134 Build_Derived_Record_Type
7135 (Full_N, Full_Parent, Full_Der, Derive_Subps);
7137 Build_Derived_Record_Type
7138 (Full_N, Full_Parent, Full_Der, Derive_Subps => False);
7143 (Full_N, Full_Parent, Full_Der,
7144 Is_Completion => False, Derive_Subps => False);
7147 -- The full declaration has been introduced into the tree and
7148 -- processed in the step above. It should not be analyzed again
7149 -- (when encountered later in the current list of declarations)
7150 -- to prevent spurious name conflicts. The full entity remains
7153 Set_Analyzed (Full_N);
7157 Make_Defining_Identifier (Sloc (Derived_Type),
7158 Chars => Chars (Derived_Type));
7159 Set_Is_Itype (Full_Der);
7160 Set_Associated_Node_For_Itype (Full_Der, N);
7161 Set_Parent (Full_Der, N);
7163 (N, Full_Parent, Full_Der,
7164 Is_Completion => False, Derive_Subps => False);
7167 Set_Has_Private_Declaration (Full_Der);
7168 Set_Has_Private_Declaration (Derived_Type);
7170 Set_Scope (Full_Der, Scope (Derived_Type));
7171 Set_Is_First_Subtype (Full_Der, Is_First_Subtype (Derived_Type));
7172 Set_Has_Size_Clause (Full_Der, False);
7173 Set_Has_Alignment_Clause (Full_Der, False);
7174 Set_Has_Delayed_Freeze (Full_Der);
7175 Set_Is_Frozen (Full_Der, False);
7176 Set_Freeze_Node (Full_Der, Empty);
7177 Set_Depends_On_Private (Full_Der, Has_Private_Component (Full_Der));
7178 Set_Is_Public (Full_Der, Is_Public (Derived_Type));
7180 -- The convention on the base type may be set in the private part
7181 -- and not propagated to the subtype until later, so we obtain the
7182 -- convention from the base type of the parent.
7184 Set_Convention (Full_Der, Convention (Base_Type (Full_Parent)));
7187 -- Start of processing for Build_Derived_Private_Type
7190 if Is_Tagged_Type (Parent_Type) then
7191 Full_P := Full_View (Parent_Type);
7193 -- A type extension of a type with unknown discriminants is an
7194 -- indefinite type that the back-end cannot handle directly.
7195 -- We treat it as a private type, and build a completion that is
7196 -- derived from the full view of the parent, and hopefully has
7197 -- known discriminants.
7199 -- If the full view of the parent type has an underlying record view,
7200 -- use it to generate the underlying record view of this derived type
7201 -- (required for chains of derivations with unknown discriminants).
7203 -- Minor optimization: we avoid the generation of useless underlying
7204 -- record view entities if the private type declaration has unknown
7205 -- discriminants but its corresponding full view has no
7208 if Has_Unknown_Discriminants (Parent_Type)
7209 and then Present (Full_P)
7210 and then (Has_Discriminants (Full_P)
7211 or else Present (Underlying_Record_View (Full_P)))
7212 and then not In_Open_Scopes (Par_Scope)
7213 and then Expander_Active
7216 Full_Der : constant Entity_Id := Make_Temporary (Loc, 'T');
7217 New_Ext : constant Node_Id :=
7219 (Record_Extension_Part (Type_Definition (N)));
7223 Build_Derived_Record_Type
7224 (N, Parent_Type, Derived_Type, Derive_Subps);
7226 -- Build anonymous completion, as a derivation from the full
7227 -- view of the parent. This is not a completion in the usual
7228 -- sense, because the current type is not private.
7231 Make_Full_Type_Declaration (Loc,
7232 Defining_Identifier => Full_Der,
7234 Make_Derived_Type_Definition (Loc,
7235 Subtype_Indication =>
7237 (Subtype_Indication (Type_Definition (N))),
7238 Record_Extension_Part => New_Ext));
7240 -- If the parent type has an underlying record view, use it
7241 -- here to build the new underlying record view.
7243 if Present (Underlying_Record_View (Full_P)) then
7245 (Nkind (Subtype_Indication (Type_Definition (Decl)))
7247 Set_Entity (Subtype_Indication (Type_Definition (Decl)),
7248 Underlying_Record_View (Full_P));
7251 Install_Private_Declarations (Par_Scope);
7252 Install_Visible_Declarations (Par_Scope);
7253 Insert_Before (N, Decl);
7255 -- Mark entity as an underlying record view before analysis,
7256 -- to avoid generating the list of its primitive operations
7257 -- (which is not really required for this entity) and thus
7258 -- prevent spurious errors associated with missing overriding
7259 -- of abstract primitives (overridden only for Derived_Type).
7261 Set_Ekind (Full_Der, E_Record_Type);
7262 Set_Is_Underlying_Record_View (Full_Der);
7263 Set_Default_SSO (Full_Der);
7267 pragma Assert (Has_Discriminants (Full_Der)
7268 and then not Has_Unknown_Discriminants (Full_Der));
7270 Uninstall_Declarations (Par_Scope);
7272 -- Freeze the underlying record view, to prevent generation of
7273 -- useless dispatching information, which is simply shared with
7274 -- the real derived type.
7276 Set_Is_Frozen (Full_Der);
7278 -- If the derived type has access discriminants, create
7279 -- references to their anonymous types now, to prevent
7280 -- back-end problems when their first use is in generated
7281 -- bodies of primitives.
7287 E := First_Entity (Full_Der);
7289 while Present (E) loop
7290 if Ekind (E) = E_Discriminant
7291 and then Ekind (Etype (E)) = E_Anonymous_Access_Type
7293 Build_Itype_Reference (Etype (E), Decl);
7300 -- Set up links between real entity and underlying record view
7302 Set_Underlying_Record_View (Derived_Type, Base_Type (Full_Der));
7303 Set_Underlying_Record_View (Base_Type (Full_Der), Derived_Type);
7306 -- If discriminants are known, build derived record
7309 Build_Derived_Record_Type
7310 (N, Parent_Type, Derived_Type, Derive_Subps);
7315 elsif Has_Discriminants (Parent_Type) then
7317 -- Build partial view of derived type from partial view of parent.
7318 -- This must be done before building the full derivation because the
7319 -- second derivation will modify the discriminants of the first and
7320 -- the discriminants are chained with the rest of the components in
7321 -- the full derivation.
7323 Build_Derived_Record_Type
7324 (N, Parent_Type, Derived_Type, Derive_Subps);
7326 -- Build the full derivation if this is not the anonymous derived
7327 -- base type created by Build_Derived_Record_Type in the constrained
7328 -- case (see point 5. of its head comment) since we build it for the
7329 -- derived subtype. And skip it for protected types altogether, as
7330 -- gigi does not use these types directly.
7332 if Present (Full_View (Parent_Type))
7333 and then not Is_Itype (Derived_Type)
7334 and then not (Ekind (Full_View (Parent_Type)) in Protected_Kind)
7337 Der_Base : constant Entity_Id := Base_Type (Derived_Type);
7339 Last_Discr : Entity_Id;
7342 -- If this is not a completion, construct the implicit full
7343 -- view by deriving from the full view of the parent type.
7344 -- But if this is a completion, the derived private type
7345 -- being built is a full view and the full derivation can
7346 -- only be its underlying full view.
7348 Build_Full_Derivation;
7350 if not Is_Completion then
7351 Set_Full_View (Derived_Type, Full_Der);
7353 Set_Underlying_Full_View (Derived_Type, Full_Der);
7356 if not Is_Base_Type (Derived_Type) then
7357 Set_Full_View (Der_Base, Base_Type (Full_Der));
7360 -- Copy the discriminant list from full view to the partial
7361 -- view (base type and its subtype). Gigi requires that the
7362 -- partial and full views have the same discriminants.
7364 -- Note that since the partial view points to discriminants
7365 -- in the full view, their scope will be that of the full
7366 -- view. This might cause some front end problems and need
7369 Discr := First_Discriminant (Base_Type (Full_Der));
7370 Set_First_Entity (Der_Base, Discr);
7373 Last_Discr := Discr;
7374 Next_Discriminant (Discr);
7375 exit when No (Discr);
7378 Set_Last_Entity (Der_Base, Last_Discr);
7379 Set_First_Entity (Derived_Type, First_Entity (Der_Base));
7380 Set_Last_Entity (Derived_Type, Last_Entity (Der_Base));
7382 Set_Stored_Constraint
7383 (Full_Der, Stored_Constraint (Derived_Type));
7387 elsif Present (Full_View (Parent_Type))
7388 and then Has_Discriminants (Full_View (Parent_Type))
7390 if Has_Unknown_Discriminants (Parent_Type)
7391 and then Nkind (Subtype_Indication (Type_Definition (N))) =
7392 N_Subtype_Indication
7395 ("cannot constrain type with unknown discriminants",
7396 Subtype_Indication (Type_Definition (N)));
7400 -- If this is not a completion, construct the implicit full view by
7401 -- deriving from the full view of the parent type. But if this is a
7402 -- completion, the derived private type being built is a full view
7403 -- and the full derivation can only be its underlying full view.
7405 Build_Full_Derivation;
7407 if not Is_Completion then
7408 Set_Full_View (Derived_Type, Full_Der);
7410 Set_Underlying_Full_View (Derived_Type, Full_Der);
7413 -- In any case, the primitive operations are inherited from the
7414 -- parent type, not from the internal full view.
7416 Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type));
7418 if Derive_Subps then
7419 Derive_Subprograms (Parent_Type, Derived_Type);
7422 Set_Stored_Constraint (Derived_Type, No_Elist);
7424 (Derived_Type, Is_Constrained (Full_View (Parent_Type)));
7427 -- Untagged type, No discriminants on either view
7429 if Nkind (Subtype_Indication (Type_Definition (N))) =
7430 N_Subtype_Indication
7433 ("illegal constraint on type without discriminants", N);
7436 if Present (Discriminant_Specifications (N))
7437 and then Present (Full_View (Parent_Type))
7438 and then not Is_Tagged_Type (Full_View (Parent_Type))
7440 Error_Msg_N ("cannot add discriminants to untagged type", N);
7443 Set_Stored_Constraint (Derived_Type, No_Elist);
7444 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
7445 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
7446 Set_Disable_Controlled (Derived_Type, Disable_Controlled
7448 Set_Has_Controlled_Component
7449 (Derived_Type, Has_Controlled_Component
7452 -- Direct controlled types do not inherit Finalize_Storage_Only flag
7454 if not Is_Controlled_Active (Parent_Type) then
7455 Set_Finalize_Storage_Only
7456 (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type));
7459 -- If this is not a completion, construct the implicit full view by
7460 -- deriving from the full view of the parent type.
7462 -- ??? If the parent is untagged private and its completion is
7463 -- tagged, this mechanism will not work because we cannot derive from
7464 -- the tagged full view unless we have an extension.
7466 if Present (Full_View (Parent_Type))
7467 and then not Is_Tagged_Type (Full_View (Parent_Type))
7468 and then not Is_Completion
7470 Build_Full_Derivation;
7471 Set_Full_View (Derived_Type, Full_Der);
7475 Set_Has_Unknown_Discriminants (Derived_Type,
7476 Has_Unknown_Discriminants (Parent_Type));
7478 if Is_Private_Type (Derived_Type) then
7479 Set_Private_Dependents (Derived_Type, New_Elmt_List);
7482 -- If the parent base type is in scope, add the derived type to its
7483 -- list of private dependents, because its full view may become
7484 -- visible subsequently (in a nested private part, a body, or in a
7485 -- further child unit).
7487 if Is_Private_Type (Par_Base) and then In_Open_Scopes (Par_Scope) then
7488 Append_Elmt (Derived_Type, Private_Dependents (Parent_Type));
7490 -- Check for unusual case where a type completed by a private
7491 -- derivation occurs within a package nested in a child unit, and
7492 -- the parent is declared in an ancestor.
7494 if Is_Child_Unit (Scope (Current_Scope))
7495 and then Is_Completion
7496 and then In_Private_Part (Current_Scope)
7497 and then Scope (Parent_Type) /= Current_Scope
7499 -- Note that if the parent has a completion in the private part,
7500 -- (which is itself a derivation from some other private type)
7501 -- it is that completion that is visible, there is no full view
7502 -- available, and no special processing is needed.
7504 and then Present (Full_View (Parent_Type))
7506 -- In this case, the full view of the parent type will become
7507 -- visible in the body of the enclosing child, and only then will
7508 -- the current type be possibly non-private. Build an underlying
7509 -- full view that will be installed when the enclosing child body
7512 if Present (Underlying_Full_View (Derived_Type)) then
7513 Full_Der := Underlying_Full_View (Derived_Type);
7515 Build_Full_Derivation;
7516 Set_Underlying_Full_View (Derived_Type, Full_Der);
7519 -- The full view will be used to swap entities on entry/exit to
7520 -- the body, and must appear in the entity list for the package.
7522 Append_Entity (Full_Der, Scope (Derived_Type));
7525 end Build_Derived_Private_Type;
7527 -------------------------------
7528 -- Build_Derived_Record_Type --
7529 -------------------------------
7533 -- Ideally we would like to use the same model of type derivation for
7534 -- tagged and untagged record types. Unfortunately this is not quite
7535 -- possible because the semantics of representation clauses is different
7536 -- for tagged and untagged records under inheritance. Consider the
7539 -- type R (...) is [tagged] record ... end record;
7540 -- type T (...) is new R (...) [with ...];
7542 -- The representation clauses for T can specify a completely different
7543 -- record layout from R's. Hence the same component can be placed in two
7544 -- very different positions in objects of type T and R. If R and T are
7545 -- tagged types, representation clauses for T can only specify the layout
7546 -- of non inherited components, thus components that are common in R and T
7547 -- have the same position in objects of type R and T.
7549 -- This has two implications. The first is that the entire tree for R's
7550 -- declaration needs to be copied for T in the untagged case, so that T
7551 -- can be viewed as a record type of its own with its own representation
7552 -- clauses. The second implication is the way we handle discriminants.
7553 -- Specifically, in the untagged case we need a way to communicate to Gigi
7554 -- what are the real discriminants in the record, while for the semantics
7555 -- we need to consider those introduced by the user to rename the
7556 -- discriminants in the parent type. This is handled by introducing the
7557 -- notion of stored discriminants. See below for more.
7559 -- Fortunately the way regular components are inherited can be handled in
7560 -- the same way in tagged and untagged types.
7562 -- To complicate things a bit more the private view of a private extension
7563 -- cannot be handled in the same way as the full view (for one thing the
7564 -- semantic rules are somewhat different). We will explain what differs
7567 -- 2. DISCRIMINANTS UNDER INHERITANCE
7569 -- The semantic rules governing the discriminants of derived types are
7572 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
7573 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
7575 -- If parent type has discriminants, then the discriminants that are
7576 -- declared in the derived type are [3.4 (11)]:
7578 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
7581 -- o Otherwise, each discriminant of the parent type (implicitly declared
7582 -- in the same order with the same specifications). In this case, the
7583 -- discriminants are said to be "inherited", or if unknown in the parent
7584 -- are also unknown in the derived type.
7586 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
7588 -- o The parent subtype must be constrained;
7590 -- o If the parent type is not a tagged type, then each discriminant of
7591 -- the derived type must be used in the constraint defining a parent
7592 -- subtype. [Implementation note: This ensures that the new discriminant
7593 -- can share storage with an existing discriminant.]
7595 -- For the derived type each discriminant of the parent type is either
7596 -- inherited, constrained to equal some new discriminant of the derived
7597 -- type, or constrained to the value of an expression.
7599 -- When inherited or constrained to equal some new discriminant, the
7600 -- parent discriminant and the discriminant of the derived type are said
7603 -- If a discriminant of the parent type is constrained to a specific value
7604 -- in the derived type definition, then the discriminant is said to be
7605 -- "specified" by that derived type definition.
7607 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES
7609 -- We have spoken about stored discriminants in point 1 (introduction)
7610 -- above. There are two sort of stored discriminants: implicit and
7611 -- explicit. As long as the derived type inherits the same discriminants as
7612 -- the root record type, stored discriminants are the same as regular
7613 -- discriminants, and are said to be implicit. However, if any discriminant
7614 -- in the root type was renamed in the derived type, then the derived
7615 -- type will contain explicit stored discriminants. Explicit stored
7616 -- discriminants are discriminants in addition to the semantically visible
7617 -- discriminants defined for the derived type. Stored discriminants are
7618 -- used by Gigi to figure out what are the physical discriminants in
7619 -- objects of the derived type (see precise definition in einfo.ads).
7620 -- As an example, consider the following:
7622 -- type R (D1, D2, D3 : Int) is record ... end record;
7623 -- type T1 is new R;
7624 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
7625 -- type T3 is new T2;
7626 -- type T4 (Y : Int) is new T3 (Y, 99);
7628 -- The following table summarizes the discriminants and stored
7629 -- discriminants in R and T1 through T4.
7631 -- Type Discrim Stored Discrim Comment
7632 -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R
7633 -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1
7634 -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2
7635 -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3
7636 -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4
7638 -- Field Corresponding_Discriminant (abbreviated CD below) allows us to
7639 -- find the corresponding discriminant in the parent type, while
7640 -- Original_Record_Component (abbreviated ORC below), the actual physical
7641 -- component that is renamed. Finally the field Is_Completely_Hidden
7642 -- (abbreviated ICH below) is set for all explicit stored discriminants
7643 -- (see einfo.ads for more info). For the above example this gives:
7645 -- Discrim CD ORC ICH
7646 -- ^^^^^^^ ^^ ^^^ ^^^
7647 -- D1 in R empty itself no
7648 -- D2 in R empty itself no
7649 -- D3 in R empty itself no
7651 -- D1 in T1 D1 in R itself no
7652 -- D2 in T1 D2 in R itself no
7653 -- D3 in T1 D3 in R itself no
7655 -- X1 in T2 D3 in T1 D3 in T2 no
7656 -- X2 in T2 D1 in T1 D1 in T2 no
7657 -- D1 in T2 empty itself yes
7658 -- D2 in T2 empty itself yes
7659 -- D3 in T2 empty itself yes
7661 -- X1 in T3 X1 in T2 D3 in T3 no
7662 -- X2 in T3 X2 in T2 D1 in T3 no
7663 -- D1 in T3 empty itself yes
7664 -- D2 in T3 empty itself yes
7665 -- D3 in T3 empty itself yes
7667 -- Y in T4 X1 in T3 D3 in T3 no
7668 -- D1 in T3 empty itself yes
7669 -- D2 in T3 empty itself yes
7670 -- D3 in T3 empty itself yes
7672 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES
7674 -- Type derivation for tagged types is fairly straightforward. If no
7675 -- discriminants are specified by the derived type, these are inherited
7676 -- from the parent. No explicit stored discriminants are ever necessary.
7677 -- The only manipulation that is done to the tree is that of adding a
7678 -- _parent field with parent type and constrained to the same constraint
7679 -- specified for the parent in the derived type definition. For instance:
7681 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
7682 -- type T1 is new R with null record;
7683 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
7685 -- are changed into:
7687 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
7688 -- _parent : R (D1, D2, D3);
7691 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
7692 -- _parent : T1 (X2, 88, X1);
7695 -- The discriminants actually present in R, T1 and T2 as well as their CD,
7696 -- ORC and ICH fields are:
7698 -- Discrim CD ORC ICH
7699 -- ^^^^^^^ ^^ ^^^ ^^^
7700 -- D1 in R empty itself no
7701 -- D2 in R empty itself no
7702 -- D3 in R empty itself no
7704 -- D1 in T1 D1 in R D1 in R no
7705 -- D2 in T1 D2 in R D2 in R no
7706 -- D3 in T1 D3 in R D3 in R no
7708 -- X1 in T2 D3 in T1 D3 in R no
7709 -- X2 in T2 D1 in T1 D1 in R no
7711 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS
7713 -- Regardless of whether we dealing with a tagged or untagged type
7714 -- we will transform all derived type declarations of the form
7716 -- type T is new R (...) [with ...];
7718 -- subtype S is R (...);
7719 -- type T is new S [with ...];
7721 -- type BT is new R [with ...];
7722 -- subtype T is BT (...);
7724 -- That is, the base derived type is constrained only if it has no
7725 -- discriminants. The reason for doing this is that GNAT's semantic model
7726 -- assumes that a base type with discriminants is unconstrained.
7728 -- Note that, strictly speaking, the above transformation is not always
7729 -- correct. Consider for instance the following excerpt from ACVC b34011a:
7731 -- procedure B34011A is
7732 -- type REC (D : integer := 0) is record
7737 -- type T6 is new Rec;
7738 -- function F return T6;
7743 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
7746 -- The definition of Q6.U is illegal. However transforming Q6.U into
7748 -- type BaseU is new T6;
7749 -- subtype U is BaseU (Q6.F.I)
7751 -- turns U into a legal subtype, which is incorrect. To avoid this problem
7752 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
7753 -- the transformation described above.
7755 -- There is another instance where the above transformation is incorrect.
7759 -- type Base (D : Integer) is tagged null record;
7760 -- procedure P (X : Base);
7762 -- type Der is new Base (2) with null record;
7763 -- procedure P (X : Der);
7766 -- Then the above transformation turns this into
7768 -- type Der_Base is new Base with null record;
7769 -- -- procedure P (X : Base) is implicitly inherited here
7770 -- -- as procedure P (X : Der_Base).
7772 -- subtype Der is Der_Base (2);
7773 -- procedure P (X : Der);
7774 -- -- The overriding of P (X : Der_Base) is illegal since we
7775 -- -- have a parameter conformance problem.
7777 -- To get around this problem, after having semantically processed Der_Base
7778 -- and the rewritten subtype declaration for Der, we copy Der_Base field
7779 -- Discriminant_Constraint from Der so that when parameter conformance is
7780 -- checked when P is overridden, no semantic errors are flagged.
7782 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS
7784 -- Regardless of whether we are dealing with a tagged or untagged type
7785 -- we will transform all derived type declarations of the form
7787 -- type R (D1, .., Dn : ...) is [tagged] record ...;
7788 -- type T is new R [with ...];
7790 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
7792 -- The reason for such transformation is that it allows us to implement a
7793 -- very clean form of component inheritance as explained below.
7795 -- Note that this transformation is not achieved by direct tree rewriting
7796 -- and manipulation, but rather by redoing the semantic actions that the
7797 -- above transformation will entail. This is done directly in routine
7798 -- Inherit_Components.
7800 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE
7802 -- In both tagged and untagged derived types, regular non discriminant
7803 -- components are inherited in the derived type from the parent type. In
7804 -- the absence of discriminants component, inheritance is straightforward
7805 -- as components can simply be copied from the parent.
7807 -- If the parent has discriminants, inheriting components constrained with
7808 -- these discriminants requires caution. Consider the following example:
7810 -- type R (D1, D2 : Positive) is [tagged] record
7811 -- S : String (D1 .. D2);
7814 -- type T1 is new R [with null record];
7815 -- type T2 (X : positive) is new R (1, X) [with null record];
7817 -- As explained in 6. above, T1 is rewritten as
7818 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
7819 -- which makes the treatment for T1 and T2 identical.
7821 -- What we want when inheriting S, is that references to D1 and D2 in R are
7822 -- replaced with references to their correct constraints, i.e. D1 and D2 in
7823 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
7824 -- with either discriminant references in the derived type or expressions.
7825 -- This replacement is achieved as follows: before inheriting R's
7826 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
7827 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
7828 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
7829 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
7830 -- by String (1 .. X).
7832 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS
7834 -- We explain here the rules governing private type extensions relevant to
7835 -- type derivation. These rules are explained on the following example:
7837 -- type D [(...)] is new A [(...)] with private; <-- partial view
7838 -- type D [(...)] is new P [(...)] with null record; <-- full view
7840 -- Type A is called the ancestor subtype of the private extension.
7841 -- Type P is the parent type of the full view of the private extension. It
7842 -- must be A or a type derived from A.
7844 -- The rules concerning the discriminants of private type extensions are
7847 -- o If a private extension inherits known discriminants from the ancestor
7848 -- subtype, then the full view must also inherit its discriminants from
7849 -- the ancestor subtype and the parent subtype of the full view must be
7850 -- constrained if and only if the ancestor subtype is constrained.
7852 -- o If a partial view has unknown discriminants, then the full view may
7853 -- define a definite or an indefinite subtype, with or without
7856 -- o If a partial view has neither known nor unknown discriminants, then
7857 -- the full view must define a definite subtype.
7859 -- o If the ancestor subtype of a private extension has constrained
7860 -- discriminants, then the parent subtype of the full view must impose a
7861 -- statically matching constraint on those discriminants.
7863 -- This means that only the following forms of private extensions are
7866 -- type D is new A with private; <-- partial view
7867 -- type D is new P with null record; <-- full view
7869 -- If A has no discriminants than P has no discriminants, otherwise P must
7870 -- inherit A's discriminants.
7872 -- type D is new A (...) with private; <-- partial view
7873 -- type D is new P (:::) with null record; <-- full view
7875 -- P must inherit A's discriminants and (...) and (:::) must statically
7878 -- subtype A is R (...);
7879 -- type D is new A with private; <-- partial view
7880 -- type D is new P with null record; <-- full view
7882 -- P must have inherited R's discriminants and must be derived from A or
7883 -- any of its subtypes.
7885 -- type D (..) is new A with private; <-- partial view
7886 -- type D (..) is new P [(:::)] with null record; <-- full view
7888 -- No specific constraints on P's discriminants or constraint (:::).
7889 -- Note that A can be unconstrained, but the parent subtype P must either
7890 -- be constrained or (:::) must be present.
7892 -- type D (..) is new A [(...)] with private; <-- partial view
7893 -- type D (..) is new P [(:::)] with null record; <-- full view
7895 -- P's constraints on A's discriminants must statically match those
7896 -- imposed by (...).
7898 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS
7900 -- The full view of a private extension is handled exactly as described
7901 -- above. The model chose for the private view of a private extension is
7902 -- the same for what concerns discriminants (i.e. they receive the same
7903 -- treatment as in the tagged case). However, the private view of the
7904 -- private extension always inherits the components of the parent base,
7905 -- without replacing any discriminant reference. Strictly speaking this is
7906 -- incorrect. However, Gigi never uses this view to generate code so this
7907 -- is a purely semantic issue. In theory, a set of transformations similar
7908 -- to those given in 5. and 6. above could be applied to private views of
7909 -- private extensions to have the same model of component inheritance as
7910 -- for non private extensions. However, this is not done because it would
7911 -- further complicate private type processing. Semantically speaking, this
7912 -- leaves us in an uncomfortable situation. As an example consider:
7915 -- type R (D : integer) is tagged record
7916 -- S : String (1 .. D);
7918 -- procedure P (X : R);
7919 -- type T is new R (1) with private;
7921 -- type T is new R (1) with null record;
7924 -- This is transformed into:
7927 -- type R (D : integer) is tagged record
7928 -- S : String (1 .. D);
7930 -- procedure P (X : R);
7931 -- type T is new R (1) with private;
7933 -- type BaseT is new R with null record;
7934 -- subtype T is BaseT (1);
7937 -- (strictly speaking the above is incorrect Ada)
7939 -- From the semantic standpoint the private view of private extension T
7940 -- should be flagged as constrained since one can clearly have
7944 -- in a unit withing Pack. However, when deriving subprograms for the
7945 -- private view of private extension T, T must be seen as unconstrained
7946 -- since T has discriminants (this is a constraint of the current
7947 -- subprogram derivation model). Thus, when processing the private view of
7948 -- a private extension such as T, we first mark T as unconstrained, we
7949 -- process it, we perform program derivation and just before returning from
7950 -- Build_Derived_Record_Type we mark T as constrained.
7952 -- ??? Are there are other uncomfortable cases that we will have to
7955 -- 10. RECORD_TYPE_WITH_PRIVATE complications
7957 -- Types that are derived from a visible record type and have a private
7958 -- extension present other peculiarities. They behave mostly like private
7959 -- types, but if they have primitive operations defined, these will not
7960 -- have the proper signatures for further inheritance, because other
7961 -- primitive operations will use the implicit base that we define for
7962 -- private derivations below. This affect subprogram inheritance (see
7963 -- Derive_Subprograms for details). We also derive the implicit base from
7964 -- the base type of the full view, so that the implicit base is a record
7965 -- type and not another private type, This avoids infinite loops.
7967 procedure Build_Derived_Record_Type
7969 Parent_Type : Entity_Id;
7970 Derived_Type : Entity_Id;
7971 Derive_Subps : Boolean := True)
7973 Discriminant_Specs : constant Boolean :=
7974 Present (Discriminant_Specifications (N));
7975 Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type);
7976 Loc : constant Source_Ptr := Sloc (N);
7977 Private_Extension : constant Boolean :=
7978 Nkind (N) = N_Private_Extension_Declaration;
7979 Assoc_List : Elist_Id;
7980 Constraint_Present : Boolean;
7982 Discrim : Entity_Id;
7984 Inherit_Discrims : Boolean := False;
7985 Last_Discrim : Entity_Id;
7986 New_Base : Entity_Id;
7988 New_Discrs : Elist_Id;
7989 New_Indic : Node_Id;
7990 Parent_Base : Entity_Id;
7991 Save_Etype : Entity_Id;
7992 Save_Discr_Constr : Elist_Id;
7993 Save_Next_Entity : Entity_Id;
7996 Discs : Elist_Id := New_Elmt_List;
7997 -- An empty Discs list means that there were no constraints in the
7998 -- subtype indication or that there was an error processing it.
8001 if Ekind (Parent_Type) = E_Record_Type_With_Private
8002 and then Present (Full_View (Parent_Type))
8003 and then Has_Discriminants (Parent_Type)
8005 Parent_Base := Base_Type (Full_View (Parent_Type));
8007 Parent_Base := Base_Type (Parent_Type);
8010 -- AI05-0115 : if this is a derivation from a private type in some
8011 -- other scope that may lead to invisible components for the derived
8012 -- type, mark it accordingly.
8014 if Is_Private_Type (Parent_Type) then
8015 if Scope (Parent_Type) = Scope (Derived_Type) then
8018 elsif In_Open_Scopes (Scope (Parent_Type))
8019 and then In_Private_Part (Scope (Parent_Type))
8024 Set_Has_Private_Ancestor (Derived_Type);
8028 Set_Has_Private_Ancestor
8029 (Derived_Type, Has_Private_Ancestor (Parent_Type));
8032 -- Before we start the previously documented transformations, here is
8033 -- little fix for size and alignment of tagged types. Normally when we
8034 -- derive type D from type P, we copy the size and alignment of P as the
8035 -- default for D, and in the absence of explicit representation clauses
8036 -- for D, the size and alignment are indeed the same as the parent.
8038 -- But this is wrong for tagged types, since fields may be added, and
8039 -- the default size may need to be larger, and the default alignment may
8040 -- need to be larger.
8042 -- We therefore reset the size and alignment fields in the tagged case.
8043 -- Note that the size and alignment will in any case be at least as
8044 -- large as the parent type (since the derived type has a copy of the
8045 -- parent type in the _parent field)
8047 -- The type is also marked as being tagged here, which is needed when
8048 -- processing components with a self-referential anonymous access type
8049 -- in the call to Check_Anonymous_Access_Components below. Note that
8050 -- this flag is also set later on for completeness.
8053 Set_Is_Tagged_Type (Derived_Type);
8054 Init_Size_Align (Derived_Type);
8057 -- STEP 0a: figure out what kind of derived type declaration we have
8059 if Private_Extension then
8061 Set_Ekind (Derived_Type, E_Record_Type_With_Private);
8062 Set_Default_SSO (Derived_Type);
8065 Type_Def := Type_Definition (N);
8067 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
8068 -- Parent_Base can be a private type or private extension. However,
8069 -- for tagged types with an extension the newly added fields are
8070 -- visible and hence the Derived_Type is always an E_Record_Type.
8071 -- (except that the parent may have its own private fields).
8072 -- For untagged types we preserve the Ekind of the Parent_Base.
8074 if Present (Record_Extension_Part (Type_Def)) then
8075 Set_Ekind (Derived_Type, E_Record_Type);
8076 Set_Default_SSO (Derived_Type);
8078 -- Create internal access types for components with anonymous
8081 if Ada_Version >= Ada_2005 then
8082 Check_Anonymous_Access_Components
8083 (N, Derived_Type, Derived_Type,
8084 Component_List (Record_Extension_Part (Type_Def)));
8088 Set_Ekind (Derived_Type, Ekind (Parent_Base));
8092 -- Indic can either be an N_Identifier if the subtype indication
8093 -- contains no constraint or an N_Subtype_Indication if the subtype
8094 -- indication has a constraint.
8096 Indic := Subtype_Indication (Type_Def);
8097 Constraint_Present := (Nkind (Indic) = N_Subtype_Indication);
8099 -- Check that the type has visible discriminants. The type may be
8100 -- a private type with unknown discriminants whose full view has
8101 -- discriminants which are invisible.
8103 if Constraint_Present then
8104 if not Has_Discriminants (Parent_Base)
8106 (Has_Unknown_Discriminants (Parent_Base)
8107 and then Is_Private_Type (Parent_Base))
8110 ("invalid constraint: type has no discriminant",
8111 Constraint (Indic));
8113 Constraint_Present := False;
8114 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
8116 elsif Is_Constrained (Parent_Type) then
8118 ("invalid constraint: parent type is already constrained",
8119 Constraint (Indic));
8121 Constraint_Present := False;
8122 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
8126 -- STEP 0b: If needed, apply transformation given in point 5. above
8128 if not Private_Extension
8129 and then Has_Discriminants (Parent_Type)
8130 and then not Discriminant_Specs
8131 and then (Is_Constrained (Parent_Type) or else Constraint_Present)
8133 -- First, we must analyze the constraint (see comment in point 5.)
8134 -- The constraint may come from the subtype indication of the full
8137 if Constraint_Present then
8138 New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic);
8140 -- If there is no explicit constraint, there might be one that is
8141 -- inherited from a constrained parent type. In that case verify that
8142 -- it conforms to the constraint in the partial view. In perverse
8143 -- cases the parent subtypes of the partial and full view can have
8144 -- different constraints.
8146 elsif Present (Stored_Constraint (Parent_Type)) then
8147 New_Discrs := Stored_Constraint (Parent_Type);
8150 New_Discrs := No_Elist;
8153 if Has_Discriminants (Derived_Type)
8154 and then Has_Private_Declaration (Derived_Type)
8155 and then Present (Discriminant_Constraint (Derived_Type))
8156 and then Present (New_Discrs)
8158 -- Verify that constraints of the full view statically match
8159 -- those given in the partial view.
8165 C1 := First_Elmt (New_Discrs);
8166 C2 := First_Elmt (Discriminant_Constraint (Derived_Type));
8167 while Present (C1) and then Present (C2) loop
8168 if Fully_Conformant_Expressions (Node (C1), Node (C2))
8170 (Is_OK_Static_Expression (Node (C1))
8171 and then Is_OK_Static_Expression (Node (C2))
8173 Expr_Value (Node (C1)) = Expr_Value (Node (C2)))
8178 if Constraint_Present then
8180 ("constraint not conformant to previous declaration",
8184 ("constraint of full view is incompatible "
8185 & "with partial view", N);
8195 -- Insert and analyze the declaration for the unconstrained base type
8197 New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B');
8200 Make_Full_Type_Declaration (Loc,
8201 Defining_Identifier => New_Base,
8203 Make_Derived_Type_Definition (Loc,
8204 Abstract_Present => Abstract_Present (Type_Def),
8205 Limited_Present => Limited_Present (Type_Def),
8206 Subtype_Indication =>
8207 New_Occurrence_Of (Parent_Base, Loc),
8208 Record_Extension_Part =>
8209 Relocate_Node (Record_Extension_Part (Type_Def)),
8210 Interface_List => Interface_List (Type_Def)));
8212 Set_Parent (New_Decl, Parent (N));
8213 Mark_Rewrite_Insertion (New_Decl);
8214 Insert_Before (N, New_Decl);
8216 -- In the extension case, make sure ancestor is frozen appropriately
8217 -- (see also non-discriminated case below).
8219 if Present (Record_Extension_Part (Type_Def))
8220 or else Is_Interface (Parent_Base)
8222 Freeze_Before (New_Decl, Parent_Type);
8225 -- Note that this call passes False for the Derive_Subps parameter
8226 -- because subprogram derivation is deferred until after creating
8227 -- the subtype (see below).
8230 (New_Decl, Parent_Base, New_Base,
8231 Is_Completion => False, Derive_Subps => False);
8233 -- ??? This needs re-examination to determine whether the
8234 -- above call can simply be replaced by a call to Analyze.
8236 Set_Analyzed (New_Decl);
8238 -- Insert and analyze the declaration for the constrained subtype
8240 if Constraint_Present then
8242 Make_Subtype_Indication (Loc,
8243 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8244 Constraint => Relocate_Node (Constraint (Indic)));
8248 Constr_List : constant List_Id := New_List;
8253 C := First_Elmt (Discriminant_Constraint (Parent_Type));
8254 while Present (C) loop
8257 -- It is safe here to call New_Copy_Tree since we called
8258 -- Force_Evaluation on each constraint previously
8259 -- in Build_Discriminant_Constraints.
8261 Append (New_Copy_Tree (Expr), To => Constr_List);
8267 Make_Subtype_Indication (Loc,
8268 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8270 Make_Index_Or_Discriminant_Constraint (Loc, Constr_List));
8275 Make_Subtype_Declaration (Loc,
8276 Defining_Identifier => Derived_Type,
8277 Subtype_Indication => New_Indic));
8281 -- Derivation of subprograms must be delayed until the full subtype
8282 -- has been established, to ensure proper overriding of subprograms
8283 -- inherited by full types. If the derivations occurred as part of
8284 -- the call to Build_Derived_Type above, then the check for type
8285 -- conformance would fail because earlier primitive subprograms
8286 -- could still refer to the full type prior the change to the new
8287 -- subtype and hence would not match the new base type created here.
8288 -- Subprograms are not derived, however, when Derive_Subps is False
8289 -- (since otherwise there could be redundant derivations).
8291 if Derive_Subps then
8292 Derive_Subprograms (Parent_Type, Derived_Type);
8295 -- For tagged types the Discriminant_Constraint of the new base itype
8296 -- is inherited from the first subtype so that no subtype conformance
8297 -- problem arise when the first subtype overrides primitive
8298 -- operations inherited by the implicit base type.
8301 Set_Discriminant_Constraint
8302 (New_Base, Discriminant_Constraint (Derived_Type));
8308 -- If we get here Derived_Type will have no discriminants or it will be
8309 -- a discriminated unconstrained base type.
8311 -- STEP 1a: perform preliminary actions/checks for derived tagged types
8315 -- The parent type is frozen for non-private extensions (RM 13.14(7))
8316 -- The declaration of a specific descendant of an interface type
8317 -- freezes the interface type (RM 13.14).
8319 if not Private_Extension or else Is_Interface (Parent_Base) then
8320 Freeze_Before (N, Parent_Type);
8323 -- In Ada 2005 (AI-344), the restriction that a derived tagged type
8324 -- cannot be declared at a deeper level than its parent type is
8325 -- removed. The check on derivation within a generic body is also
8326 -- relaxed, but there's a restriction that a derived tagged type
8327 -- cannot be declared in a generic body if it's derived directly
8328 -- or indirectly from a formal type of that generic.
8330 if Ada_Version >= Ada_2005 then
8331 if Present (Enclosing_Generic_Body (Derived_Type)) then
8333 Ancestor_Type : Entity_Id;
8336 -- Check to see if any ancestor of the derived type is a
8339 Ancestor_Type := Parent_Type;
8340 while not Is_Generic_Type (Ancestor_Type)
8341 and then Etype (Ancestor_Type) /= Ancestor_Type
8343 Ancestor_Type := Etype (Ancestor_Type);
8346 -- If the derived type does have a formal type as an
8347 -- ancestor, then it's an error if the derived type is
8348 -- declared within the body of the generic unit that
8349 -- declares the formal type in its generic formal part. It's
8350 -- sufficient to check whether the ancestor type is declared
8351 -- inside the same generic body as the derived type (such as
8352 -- within a nested generic spec), in which case the
8353 -- derivation is legal. If the formal type is declared
8354 -- outside of that generic body, then it's guaranteed that
8355 -- the derived type is declared within the generic body of
8356 -- the generic unit declaring the formal type.
8358 if Is_Generic_Type (Ancestor_Type)
8359 and then Enclosing_Generic_Body (Ancestor_Type) /=
8360 Enclosing_Generic_Body (Derived_Type)
8363 ("parent type of& must not be descendant of formal type"
8364 & " of an enclosing generic body",
8365 Indic, Derived_Type);
8370 elsif Type_Access_Level (Derived_Type) /=
8371 Type_Access_Level (Parent_Type)
8372 and then not Is_Generic_Type (Derived_Type)
8374 if Is_Controlled (Parent_Type) then
8376 ("controlled type must be declared at the library level",
8380 ("type extension at deeper accessibility level than parent",
8386 GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type);
8389 and then GB /= Enclosing_Generic_Body (Parent_Base)
8392 ("parent type of& must not be outside generic body"
8394 Indic, Derived_Type);
8400 -- Ada 2005 (AI-251)
8402 if Ada_Version >= Ada_2005 and then Is_Tagged then
8404 -- "The declaration of a specific descendant of an interface type
8405 -- freezes the interface type" (RM 13.14).
8410 if Is_Non_Empty_List (Interface_List (Type_Def)) then
8411 Iface := First (Interface_List (Type_Def));
8412 while Present (Iface) loop
8413 Freeze_Before (N, Etype (Iface));
8420 -- STEP 1b : preliminary cleanup of the full view of private types
8422 -- If the type is already marked as having discriminants, then it's the
8423 -- completion of a private type or private extension and we need to
8424 -- retain the discriminants from the partial view if the current
8425 -- declaration has Discriminant_Specifications so that we can verify
8426 -- conformance. However, we must remove any existing components that
8427 -- were inherited from the parent (and attached in Copy_And_Swap)
8428 -- because the full type inherits all appropriate components anyway, and
8429 -- we do not want the partial view's components interfering.
8431 if Has_Discriminants (Derived_Type) and then Discriminant_Specs then
8432 Discrim := First_Discriminant (Derived_Type);
8434 Last_Discrim := Discrim;
8435 Next_Discriminant (Discrim);
8436 exit when No (Discrim);
8439 Set_Last_Entity (Derived_Type, Last_Discrim);
8441 -- In all other cases wipe out the list of inherited components (even
8442 -- inherited discriminants), it will be properly rebuilt here.
8445 Set_First_Entity (Derived_Type, Empty);
8446 Set_Last_Entity (Derived_Type, Empty);
8449 -- STEP 1c: Initialize some flags for the Derived_Type
8451 -- The following flags must be initialized here so that
8452 -- Process_Discriminants can check that discriminants of tagged types do
8453 -- not have a default initial value and that access discriminants are
8454 -- only specified for limited records. For completeness, these flags are
8455 -- also initialized along with all the other flags below.
8457 -- AI-419: Limitedness is not inherited from an interface parent, so to
8458 -- be limited in that case the type must be explicitly declared as
8459 -- limited. However, task and protected interfaces are always limited.
8461 if Limited_Present (Type_Def) then
8462 Set_Is_Limited_Record (Derived_Type);
8464 elsif Is_Limited_Record (Parent_Type)
8465 or else (Present (Full_View (Parent_Type))
8466 and then Is_Limited_Record (Full_View (Parent_Type)))
8468 if not Is_Interface (Parent_Type)
8469 or else Is_Synchronized_Interface (Parent_Type)
8470 or else Is_Protected_Interface (Parent_Type)
8471 or else Is_Task_Interface (Parent_Type)
8473 Set_Is_Limited_Record (Derived_Type);
8477 -- STEP 2a: process discriminants of derived type if any
8479 Push_Scope (Derived_Type);
8481 if Discriminant_Specs then
8482 Set_Has_Unknown_Discriminants (Derived_Type, False);
8484 -- The following call initializes fields Has_Discriminants and
8485 -- Discriminant_Constraint, unless we are processing the completion
8486 -- of a private type declaration.
8488 Check_Or_Process_Discriminants (N, Derived_Type);
8490 -- For untagged types, the constraint on the Parent_Type must be
8491 -- present and is used to rename the discriminants.
8493 if not Is_Tagged and then not Has_Discriminants (Parent_Type) then
8494 Error_Msg_N ("untagged parent must have discriminants", Indic);
8496 elsif not Is_Tagged and then not Constraint_Present then
8498 ("discriminant constraint needed for derived untagged records",
8501 -- Otherwise the parent subtype must be constrained unless we have a
8502 -- private extension.
8504 elsif not Constraint_Present
8505 and then not Private_Extension
8506 and then not Is_Constrained (Parent_Type)
8509 ("unconstrained type not allowed in this context", Indic);
8511 elsif Constraint_Present then
8512 -- The following call sets the field Corresponding_Discriminant
8513 -- for the discriminants in the Derived_Type.
8515 Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True);
8517 -- For untagged types all new discriminants must rename
8518 -- discriminants in the parent. For private extensions new
8519 -- discriminants cannot rename old ones (implied by [7.3(13)]).
8521 Discrim := First_Discriminant (Derived_Type);
8522 while Present (Discrim) loop
8524 and then No (Corresponding_Discriminant (Discrim))
8527 ("new discriminants must constrain old ones", Discrim);
8529 elsif Private_Extension
8530 and then Present (Corresponding_Discriminant (Discrim))
8533 ("only static constraints allowed for parent"
8534 & " discriminants in the partial view", Indic);
8538 -- If a new discriminant is used in the constraint, then its
8539 -- subtype must be statically compatible with the parent
8540 -- discriminant's subtype (3.7(15)).
8542 -- However, if the record contains an array constrained by
8543 -- the discriminant but with some different bound, the compiler
8544 -- attemps to create a smaller range for the discriminant type.
8545 -- (See exp_ch3.Adjust_Discriminants). In this case, where
8546 -- the discriminant type is a scalar type, the check must use
8547 -- the original discriminant type in the parent declaration.
8550 Corr_Disc : constant Entity_Id :=
8551 Corresponding_Discriminant (Discrim);
8552 Disc_Type : constant Entity_Id := Etype (Discrim);
8553 Corr_Type : Entity_Id;
8556 if Present (Corr_Disc) then
8557 if Is_Scalar_Type (Disc_Type) then
8559 Entity (Discriminant_Type (Parent (Corr_Disc)));
8561 Corr_Type := Etype (Corr_Disc);
8565 Subtypes_Statically_Compatible (Disc_Type, Corr_Type)
8568 ("subtype must be compatible "
8569 & "with parent discriminant",
8575 Next_Discriminant (Discrim);
8578 -- Check whether the constraints of the full view statically
8579 -- match those imposed by the parent subtype [7.3(13)].
8581 if Present (Stored_Constraint (Derived_Type)) then
8586 C1 := First_Elmt (Discs);
8587 C2 := First_Elmt (Stored_Constraint (Derived_Type));
8588 while Present (C1) and then Present (C2) loop
8590 Fully_Conformant_Expressions (Node (C1), Node (C2))
8593 ("not conformant with previous declaration",
8604 -- STEP 2b: No new discriminants, inherit discriminants if any
8607 if Private_Extension then
8608 Set_Has_Unknown_Discriminants
8610 Has_Unknown_Discriminants (Parent_Type)
8611 or else Unknown_Discriminants_Present (N));
8613 -- The partial view of the parent may have unknown discriminants,
8614 -- but if the full view has discriminants and the parent type is
8615 -- in scope they must be inherited.
8617 elsif Has_Unknown_Discriminants (Parent_Type)
8619 (not Has_Discriminants (Parent_Type)
8620 or else not In_Open_Scopes (Scope (Parent_Type)))
8622 Set_Has_Unknown_Discriminants (Derived_Type);
8625 if not Has_Unknown_Discriminants (Derived_Type)
8626 and then not Has_Unknown_Discriminants (Parent_Base)
8627 and then Has_Discriminants (Parent_Type)
8629 Inherit_Discrims := True;
8630 Set_Has_Discriminants
8631 (Derived_Type, True);
8632 Set_Discriminant_Constraint
8633 (Derived_Type, Discriminant_Constraint (Parent_Base));
8636 -- The following test is true for private types (remember
8637 -- transformation 5. is not applied to those) and in an error
8640 if Constraint_Present then
8641 Discs := Build_Discriminant_Constraints (Parent_Type, Indic);
8644 -- For now mark a new derived type as constrained only if it has no
8645 -- discriminants. At the end of Build_Derived_Record_Type we properly
8646 -- set this flag in the case of private extensions. See comments in
8647 -- point 9. just before body of Build_Derived_Record_Type.
8651 not (Inherit_Discrims
8652 or else Has_Unknown_Discriminants (Derived_Type)));
8655 -- STEP 3: initialize fields of derived type
8657 Set_Is_Tagged_Type (Derived_Type, Is_Tagged);
8658 Set_Stored_Constraint (Derived_Type, No_Elist);
8660 -- Ada 2005 (AI-251): Private type-declarations can implement interfaces
8661 -- but cannot be interfaces
8663 if not Private_Extension
8664 and then Ekind (Derived_Type) /= E_Private_Type
8665 and then Ekind (Derived_Type) /= E_Limited_Private_Type
8667 if Interface_Present (Type_Def) then
8668 Analyze_Interface_Declaration (Derived_Type, Type_Def);
8671 Set_Interfaces (Derived_Type, No_Elist);
8674 -- Fields inherited from the Parent_Type
8676 Set_Has_Specified_Layout
8677 (Derived_Type, Has_Specified_Layout (Parent_Type));
8678 Set_Is_Limited_Composite
8679 (Derived_Type, Is_Limited_Composite (Parent_Type));
8680 Set_Is_Private_Composite
8681 (Derived_Type, Is_Private_Composite (Parent_Type));
8683 if Is_Tagged_Type (Parent_Type) then
8684 Set_No_Tagged_Streams_Pragma
8685 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
8688 -- Fields inherited from the Parent_Base
8690 Set_Has_Controlled_Component
8691 (Derived_Type, Has_Controlled_Component (Parent_Base));
8692 Set_Has_Non_Standard_Rep
8693 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8694 Set_Has_Primitive_Operations
8695 (Derived_Type, Has_Primitive_Operations (Parent_Base));
8697 -- Fields inherited from the Parent_Base in the non-private case
8699 if Ekind (Derived_Type) = E_Record_Type then
8700 Set_Has_Complex_Representation
8701 (Derived_Type, Has_Complex_Representation (Parent_Base));
8704 -- Fields inherited from the Parent_Base for record types
8706 if Is_Record_Type (Derived_Type) then
8708 Parent_Full : Entity_Id;
8711 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
8712 -- Parent_Base can be a private type or private extension. Go
8713 -- to the full view here to get the E_Record_Type specific flags.
8715 if Present (Full_View (Parent_Base)) then
8716 Parent_Full := Full_View (Parent_Base);
8718 Parent_Full := Parent_Base;
8721 Set_OK_To_Reorder_Components
8722 (Derived_Type, OK_To_Reorder_Components (Parent_Full));
8726 -- Set fields for private derived types
8728 if Is_Private_Type (Derived_Type) then
8729 Set_Depends_On_Private (Derived_Type, True);
8730 Set_Private_Dependents (Derived_Type, New_Elmt_List);
8732 -- Inherit fields from non private record types. If this is the
8733 -- completion of a derivation from a private type, the parent itself
8734 -- is private, and the attributes come from its full view, which must
8738 if Is_Private_Type (Parent_Base)
8739 and then not Is_Record_Type (Parent_Base)
8741 Set_Component_Alignment
8742 (Derived_Type, Component_Alignment (Full_View (Parent_Base)));
8744 (Derived_Type, C_Pass_By_Copy (Full_View (Parent_Base)));
8746 Set_Component_Alignment
8747 (Derived_Type, Component_Alignment (Parent_Base));
8749 (Derived_Type, C_Pass_By_Copy (Parent_Base));
8753 -- Set fields for tagged types
8756 Set_Direct_Primitive_Operations (Derived_Type, New_Elmt_List);
8758 -- All tagged types defined in Ada.Finalization are controlled
8760 if Chars (Scope (Derived_Type)) = Name_Finalization
8761 and then Chars (Scope (Scope (Derived_Type))) = Name_Ada
8762 and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard
8764 Set_Is_Controlled (Derived_Type);
8766 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Base));
8769 -- Minor optimization: there is no need to generate the class-wide
8770 -- entity associated with an underlying record view.
8772 if not Is_Underlying_Record_View (Derived_Type) then
8773 Make_Class_Wide_Type (Derived_Type);
8776 Set_Is_Abstract_Type (Derived_Type, Abstract_Present (Type_Def));
8778 if Has_Discriminants (Derived_Type)
8779 and then Constraint_Present
8781 Set_Stored_Constraint
8782 (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs));
8785 if Ada_Version >= Ada_2005 then
8787 Ifaces_List : Elist_Id;
8790 -- Checks rules 3.9.4 (13/2 and 14/2)
8792 if Comes_From_Source (Derived_Type)
8793 and then not Is_Private_Type (Derived_Type)
8794 and then Is_Interface (Parent_Type)
8795 and then not Is_Interface (Derived_Type)
8797 if Is_Task_Interface (Parent_Type) then
8799 ("(Ada 2005) task type required (RM 3.9.4 (13.2))",
8802 elsif Is_Protected_Interface (Parent_Type) then
8804 ("(Ada 2005) protected type required (RM 3.9.4 (14.2))",
8809 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
8811 Check_Interfaces (N, Type_Def);
8813 -- Ada 2005 (AI-251): Collect the list of progenitors that are
8814 -- not already in the parents.
8818 Ifaces_List => Ifaces_List,
8819 Exclude_Parents => True);
8821 Set_Interfaces (Derived_Type, Ifaces_List);
8823 -- If the derived type is the anonymous type created for
8824 -- a declaration whose parent has a constraint, propagate
8825 -- the interface list to the source type. This must be done
8826 -- prior to the completion of the analysis of the source type
8827 -- because the components in the extension may contain current
8828 -- instances whose legality depends on some ancestor.
8830 if Is_Itype (Derived_Type) then
8832 Def : constant Node_Id :=
8833 Associated_Node_For_Itype (Derived_Type);
8836 and then Nkind (Def) = N_Full_Type_Declaration
8839 (Defining_Identifier (Def), Ifaces_List);
8844 -- Propagate inherited invariant information of parents
8847 if Ada_Version >= Ada_2012
8848 and then not Is_Interface (Derived_Type)
8850 if Has_Inheritable_Invariants (Parent_Type) then
8851 Set_Has_Invariants (Derived_Type);
8852 Set_Has_Inheritable_Invariants (Derived_Type);
8854 elsif not Is_Empty_Elmt_List (Ifaces_List) then
8859 AI := First_Elmt (Ifaces_List);
8860 while Present (AI) loop
8861 if Has_Inheritable_Invariants (Node (AI)) then
8862 Set_Has_Invariants (Derived_Type);
8863 Set_Has_Inheritable_Invariants (Derived_Type);
8874 -- A type extension is automatically Ghost when one of its
8875 -- progenitors is Ghost (SPARK RM 6.9(9)). This property is
8876 -- also inherited when the parent type is Ghost, but this is
8877 -- done in Build_Derived_Type as the mechanism also handles
8878 -- untagged derivations.
8880 if Implements_Ghost_Interface (Derived_Type) then
8881 Set_Is_Ghost_Entity (Derived_Type);
8887 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Base));
8888 Set_Has_Non_Standard_Rep
8889 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8892 -- STEP 4: Inherit components from the parent base and constrain them.
8893 -- Apply the second transformation described in point 6. above.
8895 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
8896 or else not Has_Discriminants (Parent_Type)
8897 or else not Is_Constrained (Parent_Type)
8901 Constrs := Discriminant_Constraint (Parent_Type);
8906 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
8908 -- STEP 5a: Copy the parent record declaration for untagged types
8910 if not Is_Tagged then
8912 -- Discriminant_Constraint (Derived_Type) has been properly
8913 -- constructed. Save it and temporarily set it to Empty because we
8914 -- do not want the call to New_Copy_Tree below to mess this list.
8916 if Has_Discriminants (Derived_Type) then
8917 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
8918 Set_Discriminant_Constraint (Derived_Type, No_Elist);
8920 Save_Discr_Constr := No_Elist;
8923 -- Save the Etype field of Derived_Type. It is correctly set now,
8924 -- but the call to New_Copy tree may remap it to point to itself,
8925 -- which is not what we want. Ditto for the Next_Entity field.
8927 Save_Etype := Etype (Derived_Type);
8928 Save_Next_Entity := Next_Entity (Derived_Type);
8930 -- Assoc_List maps all stored discriminants in the Parent_Base to
8931 -- stored discriminants in the Derived_Type. It is fundamental that
8932 -- no types or itypes with discriminants other than the stored
8933 -- discriminants appear in the entities declared inside
8934 -- Derived_Type, since the back end cannot deal with it.
8938 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
8940 -- Restore the fields saved prior to the New_Copy_Tree call
8941 -- and compute the stored constraint.
8943 Set_Etype (Derived_Type, Save_Etype);
8944 Set_Next_Entity (Derived_Type, Save_Next_Entity);
8946 if Has_Discriminants (Derived_Type) then
8947 Set_Discriminant_Constraint
8948 (Derived_Type, Save_Discr_Constr);
8949 Set_Stored_Constraint
8950 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
8951 Replace_Components (Derived_Type, New_Decl);
8952 Set_Has_Implicit_Dereference
8953 (Derived_Type, Has_Implicit_Dereference (Parent_Type));
8956 -- Insert the new derived type declaration
8958 Rewrite (N, New_Decl);
8960 -- STEP 5b: Complete the processing for record extensions in generics
8962 -- There is no completion for record extensions declared in the
8963 -- parameter part of a generic, so we need to complete processing for
8964 -- these generic record extensions here. The Record_Type_Definition call
8965 -- will change the Ekind of the components from E_Void to E_Component.
8967 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
8968 Record_Type_Definition (Empty, Derived_Type);
8970 -- STEP 5c: Process the record extension for non private tagged types
8972 elsif not Private_Extension then
8973 Expand_Record_Extension (Derived_Type, Type_Def);
8975 -- Note : previously in ASIS mode we set the Parent_Subtype of the
8976 -- derived type to propagate some semantic information. This led
8977 -- to other ASIS failures and has been removed.
8979 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
8980 -- implemented interfaces if we are in expansion mode
8983 and then Has_Interfaces (Derived_Type)
8985 Add_Interface_Tag_Components (N, Derived_Type);
8988 -- Analyze the record extension
8990 Record_Type_Definition
8991 (Record_Extension_Part (Type_Def), Derived_Type);
8996 -- Nothing else to do if there is an error in the derivation.
8997 -- An unusual case: the full view may be derived from a type in an
8998 -- instance, when the partial view was used illegally as an actual
8999 -- in that instance, leading to a circular definition.
9001 if Etype (Derived_Type) = Any_Type
9002 or else Etype (Parent_Type) = Derived_Type
9007 -- Set delayed freeze and then derive subprograms, we need to do
9008 -- this in this order so that derived subprograms inherit the
9009 -- derived freeze if necessary.
9011 Set_Has_Delayed_Freeze (Derived_Type);
9013 if Derive_Subps then
9014 Derive_Subprograms (Parent_Type, Derived_Type);
9017 -- If we have a private extension which defines a constrained derived
9018 -- type mark as constrained here after we have derived subprograms. See
9019 -- comment on point 9. just above the body of Build_Derived_Record_Type.
9021 if Private_Extension and then Inherit_Discrims then
9022 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
9023 Set_Is_Constrained (Derived_Type, True);
9024 Set_Discriminant_Constraint (Derived_Type, Discs);
9026 elsif Is_Constrained (Parent_Type) then
9028 (Derived_Type, True);
9029 Set_Discriminant_Constraint
9030 (Derived_Type, Discriminant_Constraint (Parent_Type));
9034 -- Update the class-wide type, which shares the now-completed entity
9035 -- list with its specific type. In case of underlying record views,
9036 -- we do not generate the corresponding class wide entity.
9039 and then not Is_Underlying_Record_View (Derived_Type)
9042 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
9044 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
9047 Check_Function_Writable_Actuals (N);
9048 end Build_Derived_Record_Type;
9050 ------------------------
9051 -- Build_Derived_Type --
9052 ------------------------
9054 procedure Build_Derived_Type
9056 Parent_Type : Entity_Id;
9057 Derived_Type : Entity_Id;
9058 Is_Completion : Boolean;
9059 Derive_Subps : Boolean := True)
9061 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
9064 -- Set common attributes
9066 Set_Scope (Derived_Type, Current_Scope);
9068 Set_Etype (Derived_Type, Parent_Base);
9069 Set_Ekind (Derived_Type, Ekind (Parent_Base));
9070 Set_Has_Task (Derived_Type, Has_Task (Parent_Base));
9071 Set_Has_Protected (Derived_Type, Has_Protected (Parent_Base));
9073 Set_Size_Info (Derived_Type, Parent_Type);
9074 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
9075 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
9076 Set_Disable_Controlled (Derived_Type, Disable_Controlled (Parent_Type));
9078 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
9079 Set_Is_Volatile (Derived_Type, Is_Volatile (Parent_Type));
9081 if Is_Tagged_Type (Derived_Type) then
9082 Set_No_Tagged_Streams_Pragma
9083 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
9086 -- If the parent has primitive routines, set the derived type link
9088 if Has_Primitive_Operations (Parent_Type) then
9089 Set_Derived_Type_Link (Parent_Base, Derived_Type);
9092 -- If the parent type is a private subtype, the convention on the base
9093 -- type may be set in the private part, and not propagated to the
9094 -- subtype until later, so we obtain the convention from the base type.
9096 Set_Convention (Derived_Type, Convention (Parent_Base));
9098 -- Set SSO default for record or array type
9100 if (Is_Array_Type (Derived_Type) or else Is_Record_Type (Derived_Type))
9101 and then Is_Base_Type (Derived_Type)
9103 Set_Default_SSO (Derived_Type);
9106 -- Propagate invariant information. The new type has invariants if
9107 -- they are inherited from the parent type, and these invariants can
9108 -- be further inherited, so both flags are set.
9110 -- We similarly inherit predicates
9112 if Has_Predicates (Parent_Type) then
9113 Set_Has_Predicates (Derived_Type);
9116 -- The derived type inherits the representation clauses of the parent
9118 Inherit_Rep_Item_Chain (Derived_Type, Parent_Type);
9120 -- Propagate the attributes related to pragma Default_Initial_Condition
9121 -- from the parent type to the private extension. A derived type always
9122 -- inherits the default initial condition flag from the parent type. If
9123 -- the derived type carries its own Default_Initial_Condition pragma,
9124 -- the flag is later reset in Analyze_Pragma. Note that both flags are
9125 -- mutually exclusive.
9127 Propagate_Default_Init_Cond_Attributes
9128 (From_Typ => Parent_Type,
9129 To_Typ => Derived_Type,
9130 Parent_To_Derivation => True);
9132 -- If the parent type has delayed rep aspects, then mark the derived
9133 -- type as possibly inheriting a delayed rep aspect.
9135 if Has_Delayed_Rep_Aspects (Parent_Type) then
9136 Set_May_Inherit_Delayed_Rep_Aspects (Derived_Type);
9139 -- Propagate the attributes related to pragma Ghost from the parent type
9140 -- to the derived type or type extension (SPARK RM 6.9(9)).
9142 if Is_Ghost_Entity (Parent_Type) then
9143 Set_Is_Ghost_Entity (Derived_Type);
9146 -- Type dependent processing
9148 case Ekind (Parent_Type) is
9149 when Numeric_Kind =>
9150 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
9153 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
9157 | Class_Wide_Kind =>
9158 Build_Derived_Record_Type
9159 (N, Parent_Type, Derived_Type, Derive_Subps);
9162 when Enumeration_Kind =>
9163 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
9166 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
9168 when Incomplete_Or_Private_Kind =>
9169 Build_Derived_Private_Type
9170 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
9172 -- For discriminated types, the derivation includes deriving
9173 -- primitive operations. For others it is done below.
9175 if Is_Tagged_Type (Parent_Type)
9176 or else Has_Discriminants (Parent_Type)
9177 or else (Present (Full_View (Parent_Type))
9178 and then Has_Discriminants (Full_View (Parent_Type)))
9183 when Concurrent_Kind =>
9184 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
9187 raise Program_Error;
9190 -- Nothing more to do if some error occurred
9192 if Etype (Derived_Type) = Any_Type then
9196 -- Set delayed freeze and then derive subprograms, we need to do this
9197 -- in this order so that derived subprograms inherit the derived freeze
9200 Set_Has_Delayed_Freeze (Derived_Type);
9202 if Derive_Subps then
9203 Derive_Subprograms (Parent_Type, Derived_Type);
9206 Set_Has_Primitive_Operations
9207 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
9208 end Build_Derived_Type;
9210 -----------------------
9211 -- Build_Discriminal --
9212 -----------------------
9214 procedure Build_Discriminal (Discrim : Entity_Id) is
9215 D_Minal : Entity_Id;
9216 CR_Disc : Entity_Id;
9219 -- A discriminal has the same name as the discriminant
9221 D_Minal := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
9223 Set_Ekind (D_Minal, E_In_Parameter);
9224 Set_Mechanism (D_Minal, Default_Mechanism);
9225 Set_Etype (D_Minal, Etype (Discrim));
9226 Set_Scope (D_Minal, Current_Scope);
9228 Set_Discriminal (Discrim, D_Minal);
9229 Set_Discriminal_Link (D_Minal, Discrim);
9231 -- For task types, build at once the discriminants of the corresponding
9232 -- record, which are needed if discriminants are used in entry defaults
9233 -- and in family bounds.
9235 if Is_Concurrent_Type (Current_Scope)
9237 Is_Limited_Type (Current_Scope)
9239 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
9241 Set_Ekind (CR_Disc, E_In_Parameter);
9242 Set_Mechanism (CR_Disc, Default_Mechanism);
9243 Set_Etype (CR_Disc, Etype (Discrim));
9244 Set_Scope (CR_Disc, Current_Scope);
9245 Set_Discriminal_Link (CR_Disc, Discrim);
9246 Set_CR_Discriminant (Discrim, CR_Disc);
9248 end Build_Discriminal;
9250 ------------------------------------
9251 -- Build_Discriminant_Constraints --
9252 ------------------------------------
9254 function Build_Discriminant_Constraints
9257 Derived_Def : Boolean := False) return Elist_Id
9259 C : constant Node_Id := Constraint (Def);
9260 Nb_Discr : constant Nat := Number_Discriminants (T);
9262 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
9263 -- Saves the expression corresponding to a given discriminant in T
9265 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
9266 -- Return the Position number within array Discr_Expr of a discriminant
9267 -- D within the discriminant list of the discriminated type T.
9269 procedure Process_Discriminant_Expression
9272 -- If this is a discriminant constraint on a partial view, do not
9273 -- generate an overflow check on the discriminant expression. The check
9274 -- will be generated when constraining the full view. Otherwise the
9275 -- backend creates duplicate symbols for the temporaries corresponding
9276 -- to the expressions to be checked, causing spurious assembler errors.
9282 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
9286 Disc := First_Discriminant (T);
9287 for J in Discr_Expr'Range loop
9292 Next_Discriminant (Disc);
9295 -- Note: Since this function is called on discriminants that are
9296 -- known to belong to the discriminated type, falling through the
9297 -- loop with no match signals an internal compiler error.
9299 raise Program_Error;
9302 -------------------------------------
9303 -- Process_Discriminant_Expression --
9304 -------------------------------------
9306 procedure Process_Discriminant_Expression
9310 BDT : constant Entity_Id := Base_Type (Etype (D));
9313 -- If this is a discriminant constraint on a partial view, do
9314 -- not generate an overflow on the discriminant expression. The
9315 -- check will be generated when constraining the full view.
9317 if Is_Private_Type (T)
9318 and then Present (Full_View (T))
9320 Analyze_And_Resolve (Expr, BDT, Suppress => Overflow_Check);
9322 Analyze_And_Resolve (Expr, BDT);
9324 end Process_Discriminant_Expression;
9326 -- Declarations local to Build_Discriminant_Constraints
9330 Elist : constant Elist_Id := New_Elmt_List;
9338 Discrim_Present : Boolean := False;
9340 -- Start of processing for Build_Discriminant_Constraints
9343 -- The following loop will process positional associations only.
9344 -- For a positional association, the (single) discriminant is
9345 -- implicitly specified by position, in textual order (RM 3.7.2).
9347 Discr := First_Discriminant (T);
9348 Constr := First (Constraints (C));
9349 for D in Discr_Expr'Range loop
9350 exit when Nkind (Constr) = N_Discriminant_Association;
9353 Error_Msg_N ("too few discriminants given in constraint", C);
9354 return New_Elmt_List;
9356 elsif Nkind (Constr) = N_Range
9357 or else (Nkind (Constr) = N_Attribute_Reference
9358 and then Attribute_Name (Constr) = Name_Range)
9361 ("a range is not a valid discriminant constraint", Constr);
9362 Discr_Expr (D) := Error;
9365 Process_Discriminant_Expression (Constr, Discr);
9366 Discr_Expr (D) := Constr;
9369 Next_Discriminant (Discr);
9373 if No (Discr) and then Present (Constr) then
9374 Error_Msg_N ("too many discriminants given in constraint", Constr);
9375 return New_Elmt_List;
9378 -- Named associations can be given in any order, but if both positional
9379 -- and named associations are used in the same discriminant constraint,
9380 -- then positional associations must occur first, at their normal
9381 -- position. Hence once a named association is used, the rest of the
9382 -- discriminant constraint must use only named associations.
9384 while Present (Constr) loop
9386 -- Positional association forbidden after a named association
9388 if Nkind (Constr) /= N_Discriminant_Association then
9389 Error_Msg_N ("positional association follows named one", Constr);
9390 return New_Elmt_List;
9392 -- Otherwise it is a named association
9395 -- E records the type of the discriminants in the named
9396 -- association. All the discriminants specified in the same name
9397 -- association must have the same type.
9401 -- Search the list of discriminants in T to see if the simple name
9402 -- given in the constraint matches any of them.
9404 Id := First (Selector_Names (Constr));
9405 while Present (Id) loop
9408 -- If Original_Discriminant is present, we are processing a
9409 -- generic instantiation and this is an instance node. We need
9410 -- to find the name of the corresponding discriminant in the
9411 -- actual record type T and not the name of the discriminant in
9412 -- the generic formal. Example:
9415 -- type G (D : int) is private;
9417 -- subtype W is G (D => 1);
9419 -- type Rec (X : int) is record ... end record;
9420 -- package Q is new P (G => Rec);
9422 -- At the point of the instantiation, formal type G is Rec
9423 -- and therefore when reanalyzing "subtype W is G (D => 1);"
9424 -- which really looks like "subtype W is Rec (D => 1);" at
9425 -- the point of instantiation, we want to find the discriminant
9426 -- that corresponds to D in Rec, i.e. X.
9428 if Present (Original_Discriminant (Id))
9429 and then In_Instance
9431 Discr := Find_Corresponding_Discriminant (Id, T);
9435 Discr := First_Discriminant (T);
9436 while Present (Discr) loop
9437 if Chars (Discr) = Chars (Id) then
9442 Next_Discriminant (Discr);
9446 Error_Msg_N ("& does not match any discriminant", Id);
9447 return New_Elmt_List;
9449 -- If the parent type is a generic formal, preserve the
9450 -- name of the discriminant for subsequent instances.
9451 -- see comment at the beginning of this if statement.
9453 elsif Is_Generic_Type (Root_Type (T)) then
9454 Set_Original_Discriminant (Id, Discr);
9458 Position := Pos_Of_Discr (T, Discr);
9460 if Present (Discr_Expr (Position)) then
9461 Error_Msg_N ("duplicate constraint for discriminant&", Id);
9464 -- Each discriminant specified in the same named association
9465 -- must be associated with a separate copy of the
9466 -- corresponding expression.
9468 if Present (Next (Id)) then
9469 Expr := New_Copy_Tree (Expression (Constr));
9470 Set_Parent (Expr, Parent (Expression (Constr)));
9472 Expr := Expression (Constr);
9475 Discr_Expr (Position) := Expr;
9476 Process_Discriminant_Expression (Expr, Discr);
9479 -- A discriminant association with more than one discriminant
9480 -- name is only allowed if the named discriminants are all of
9481 -- the same type (RM 3.7.1(8)).
9484 E := Base_Type (Etype (Discr));
9486 elsif Base_Type (Etype (Discr)) /= E then
9488 ("all discriminants in an association " &
9489 "must have the same type", Id);
9499 -- A discriminant constraint must provide exactly one value for each
9500 -- discriminant of the type (RM 3.7.1(8)).
9502 for J in Discr_Expr'Range loop
9503 if No (Discr_Expr (J)) then
9504 Error_Msg_N ("too few discriminants given in constraint", C);
9505 return New_Elmt_List;
9509 -- Determine if there are discriminant expressions in the constraint
9511 for J in Discr_Expr'Range loop
9512 if Denotes_Discriminant
9513 (Discr_Expr (J), Check_Concurrent => True)
9515 Discrim_Present := True;
9519 -- Build an element list consisting of the expressions given in the
9520 -- discriminant constraint and apply the appropriate checks. The list
9521 -- is constructed after resolving any named discriminant associations
9522 -- and therefore the expressions appear in the textual order of the
9525 Discr := First_Discriminant (T);
9526 for J in Discr_Expr'Range loop
9527 if Discr_Expr (J) /= Error then
9528 Append_Elmt (Discr_Expr (J), Elist);
9530 -- If any of the discriminant constraints is given by a
9531 -- discriminant and we are in a derived type declaration we
9532 -- have a discriminant renaming. Establish link between new
9533 -- and old discriminant.
9535 if Denotes_Discriminant (Discr_Expr (J)) then
9537 Set_Corresponding_Discriminant
9538 (Entity (Discr_Expr (J)), Discr);
9541 -- Force the evaluation of non-discriminant expressions.
9542 -- If we have found a discriminant in the constraint 3.4(26)
9543 -- and 3.8(18) demand that no range checks are performed are
9544 -- after evaluation. If the constraint is for a component
9545 -- definition that has a per-object constraint, expressions are
9546 -- evaluated but not checked either. In all other cases perform
9550 if Discrim_Present then
9553 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
9555 Has_Per_Object_Constraint
9556 (Defining_Identifier (Parent (Parent (Def))))
9560 elsif Is_Access_Type (Etype (Discr)) then
9561 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
9564 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
9567 Force_Evaluation (Discr_Expr (J));
9570 -- Check that the designated type of an access discriminant's
9571 -- expression is not a class-wide type unless the discriminant's
9572 -- designated type is also class-wide.
9574 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
9575 and then not Is_Class_Wide_Type
9576 (Designated_Type (Etype (Discr)))
9577 and then Etype (Discr_Expr (J)) /= Any_Type
9578 and then Is_Class_Wide_Type
9579 (Designated_Type (Etype (Discr_Expr (J))))
9581 Wrong_Type (Discr_Expr (J), Etype (Discr));
9583 elsif Is_Access_Type (Etype (Discr))
9584 and then not Is_Access_Constant (Etype (Discr))
9585 and then Is_Access_Type (Etype (Discr_Expr (J)))
9586 and then Is_Access_Constant (Etype (Discr_Expr (J)))
9589 ("constraint for discriminant& must be access to variable",
9594 Next_Discriminant (Discr);
9598 end Build_Discriminant_Constraints;
9600 ---------------------------------
9601 -- Build_Discriminated_Subtype --
9602 ---------------------------------
9604 procedure Build_Discriminated_Subtype
9608 Related_Nod : Node_Id;
9609 For_Access : Boolean := False)
9611 Has_Discrs : constant Boolean := Has_Discriminants (T);
9612 Constrained : constant Boolean :=
9614 and then not Is_Empty_Elmt_List (Elist)
9615 and then not Is_Class_Wide_Type (T))
9616 or else Is_Constrained (T);
9619 if Ekind (T) = E_Record_Type then
9621 Set_Ekind (Def_Id, E_Private_Subtype);
9622 Set_Is_For_Access_Subtype (Def_Id, True);
9624 Set_Ekind (Def_Id, E_Record_Subtype);
9627 -- Inherit preelaboration flag from base, for types for which it
9628 -- may have been set: records, private types, protected types.
9630 Set_Known_To_Have_Preelab_Init
9631 (Def_Id, Known_To_Have_Preelab_Init (T));
9633 elsif Ekind (T) = E_Task_Type then
9634 Set_Ekind (Def_Id, E_Task_Subtype);
9636 elsif Ekind (T) = E_Protected_Type then
9637 Set_Ekind (Def_Id, E_Protected_Subtype);
9638 Set_Known_To_Have_Preelab_Init
9639 (Def_Id, Known_To_Have_Preelab_Init (T));
9641 elsif Is_Private_Type (T) then
9642 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
9643 Set_Known_To_Have_Preelab_Init
9644 (Def_Id, Known_To_Have_Preelab_Init (T));
9646 -- Private subtypes may have private dependents
9648 Set_Private_Dependents (Def_Id, New_Elmt_List);
9650 elsif Is_Class_Wide_Type (T) then
9651 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
9654 -- Incomplete type. Attach subtype to list of dependents, to be
9655 -- completed with full view of parent type, unless is it the
9656 -- designated subtype of a record component within an init_proc.
9657 -- This last case arises for a component of an access type whose
9658 -- designated type is incomplete (e.g. a Taft Amendment type).
9659 -- The designated subtype is within an inner scope, and needs no
9660 -- elaboration, because only the access type is needed in the
9661 -- initialization procedure.
9663 Set_Ekind (Def_Id, Ekind (T));
9665 if For_Access and then Within_Init_Proc then
9668 Append_Elmt (Def_Id, Private_Dependents (T));
9672 Set_Etype (Def_Id, T);
9673 Init_Size_Align (Def_Id);
9674 Set_Has_Discriminants (Def_Id, Has_Discrs);
9675 Set_Is_Constrained (Def_Id, Constrained);
9677 Set_First_Entity (Def_Id, First_Entity (T));
9678 Set_Last_Entity (Def_Id, Last_Entity (T));
9679 Set_Has_Implicit_Dereference
9680 (Def_Id, Has_Implicit_Dereference (T));
9682 -- If the subtype is the completion of a private declaration, there may
9683 -- have been representation clauses for the partial view, and they must
9684 -- be preserved. Build_Derived_Type chains the inherited clauses with
9685 -- the ones appearing on the extension. If this comes from a subtype
9686 -- declaration, all clauses are inherited.
9688 if No (First_Rep_Item (Def_Id)) then
9689 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
9692 if Is_Tagged_Type (T) then
9693 Set_Is_Tagged_Type (Def_Id);
9694 Set_No_Tagged_Streams_Pragma (Def_Id, No_Tagged_Streams_Pragma (T));
9695 Make_Class_Wide_Type (Def_Id);
9698 Set_Stored_Constraint (Def_Id, No_Elist);
9701 Set_Discriminant_Constraint (Def_Id, Elist);
9702 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
9705 if Is_Tagged_Type (T) then
9707 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
9708 -- concurrent record type (which has the list of primitive
9711 if Ada_Version >= Ada_2005
9712 and then Is_Concurrent_Type (T)
9714 Set_Corresponding_Record_Type (Def_Id,
9715 Corresponding_Record_Type (T));
9717 Set_Direct_Primitive_Operations (Def_Id,
9718 Direct_Primitive_Operations (T));
9721 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
9724 -- Subtypes introduced by component declarations do not need to be
9725 -- marked as delayed, and do not get freeze nodes, because the semantics
9726 -- verifies that the parents of the subtypes are frozen before the
9727 -- enclosing record is frozen.
9729 if not Is_Type (Scope (Def_Id)) then
9730 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
9732 if Is_Private_Type (T)
9733 and then Present (Full_View (T))
9735 Conditional_Delay (Def_Id, Full_View (T));
9737 Conditional_Delay (Def_Id, T);
9741 if Is_Record_Type (T) then
9742 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
9745 and then not Is_Empty_Elmt_List (Elist)
9746 and then not For_Access
9748 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
9749 elsif not For_Access then
9750 Set_Cloned_Subtype (Def_Id, T);
9753 end Build_Discriminated_Subtype;
9755 ---------------------------
9756 -- Build_Itype_Reference --
9757 ---------------------------
9759 procedure Build_Itype_Reference
9763 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
9766 -- Itype references are only created for use by the back-end
9768 if Inside_A_Generic then
9771 Set_Itype (IR, Ityp);
9772 Insert_After (Nod, IR);
9774 end Build_Itype_Reference;
9776 ------------------------
9777 -- Build_Scalar_Bound --
9778 ------------------------
9780 function Build_Scalar_Bound
9783 Der_T : Entity_Id) return Node_Id
9785 New_Bound : Entity_Id;
9788 -- Note: not clear why this is needed, how can the original bound
9789 -- be unanalyzed at this point? and if it is, what business do we
9790 -- have messing around with it? and why is the base type of the
9791 -- parent type the right type for the resolution. It probably is
9792 -- not. It is OK for the new bound we are creating, but not for
9793 -- the old one??? Still if it never happens, no problem.
9795 Analyze_And_Resolve (Bound, Base_Type (Par_T));
9797 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
9798 New_Bound := New_Copy (Bound);
9799 Set_Etype (New_Bound, Der_T);
9800 Set_Analyzed (New_Bound);
9802 elsif Is_Entity_Name (Bound) then
9803 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
9805 -- The following is almost certainly wrong. What business do we have
9806 -- relocating a node (Bound) that is presumably still attached to
9807 -- the tree elsewhere???
9810 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
9813 Set_Etype (New_Bound, Der_T);
9815 end Build_Scalar_Bound;
9817 --------------------------------
9818 -- Build_Underlying_Full_View --
9819 --------------------------------
9821 procedure Build_Underlying_Full_View
9826 Loc : constant Source_Ptr := Sloc (N);
9827 Subt : constant Entity_Id :=
9828 Make_Defining_Identifier
9829 (Loc, New_External_Name (Chars (Typ), 'S'));
9836 procedure Set_Discriminant_Name (Id : Node_Id);
9837 -- If the derived type has discriminants, they may rename discriminants
9838 -- of the parent. When building the full view of the parent, we need to
9839 -- recover the names of the original discriminants if the constraint is
9840 -- given by named associations.
9842 ---------------------------
9843 -- Set_Discriminant_Name --
9844 ---------------------------
9846 procedure Set_Discriminant_Name (Id : Node_Id) is
9850 Set_Original_Discriminant (Id, Empty);
9852 if Has_Discriminants (Typ) then
9853 Disc := First_Discriminant (Typ);
9854 while Present (Disc) loop
9855 if Chars (Disc) = Chars (Id)
9856 and then Present (Corresponding_Discriminant (Disc))
9858 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
9860 Next_Discriminant (Disc);
9863 end Set_Discriminant_Name;
9865 -- Start of processing for Build_Underlying_Full_View
9868 if Nkind (N) = N_Full_Type_Declaration then
9869 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
9871 elsif Nkind (N) = N_Subtype_Declaration then
9872 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
9874 elsif Nkind (N) = N_Component_Declaration then
9877 (Constraint (Subtype_Indication (Component_Definition (N))));
9880 raise Program_Error;
9883 C := First (Constraints (Constr));
9884 while Present (C) loop
9885 if Nkind (C) = N_Discriminant_Association then
9886 Id := First (Selector_Names (C));
9887 while Present (Id) loop
9888 Set_Discriminant_Name (Id);
9897 Make_Subtype_Declaration (Loc,
9898 Defining_Identifier => Subt,
9899 Subtype_Indication =>
9900 Make_Subtype_Indication (Loc,
9901 Subtype_Mark => New_Occurrence_Of (Par, Loc),
9902 Constraint => New_Copy_Tree (Constr)));
9904 -- If this is a component subtype for an outer itype, it is not
9905 -- a list member, so simply set the parent link for analysis: if
9906 -- the enclosing type does not need to be in a declarative list,
9907 -- neither do the components.
9909 if Is_List_Member (N)
9910 and then Nkind (N) /= N_Component_Declaration
9912 Insert_Before (N, Indic);
9914 Set_Parent (Indic, Parent (N));
9918 Set_Underlying_Full_View (Typ, Full_View (Subt));
9919 end Build_Underlying_Full_View;
9921 -------------------------------
9922 -- Check_Abstract_Overriding --
9923 -------------------------------
9925 procedure Check_Abstract_Overriding (T : Entity_Id) is
9926 Alias_Subp : Entity_Id;
9932 procedure Check_Pragma_Implemented (Subp : Entity_Id);
9933 -- Ada 2012 (AI05-0030): Subprogram Subp overrides an interface routine
9934 -- which has pragma Implemented already set. Check whether Subp's entity
9935 -- kind conforms to the implementation kind of the overridden routine.
9937 procedure Check_Pragma_Implemented
9939 Iface_Subp : Entity_Id);
9940 -- Ada 2012 (AI05-0030): Subprogram Subp overrides interface routine
9941 -- Iface_Subp and both entities have pragma Implemented already set on
9942 -- them. Check whether the two implementation kinds are conforming.
9944 procedure Inherit_Pragma_Implemented
9946 Iface_Subp : Entity_Id);
9947 -- Ada 2012 (AI05-0030): Interface primitive Subp overrides interface
9948 -- subprogram Iface_Subp which has been marked by pragma Implemented.
9949 -- Propagate the implementation kind of Iface_Subp to Subp.
9951 ------------------------------
9952 -- Check_Pragma_Implemented --
9953 ------------------------------
9955 procedure Check_Pragma_Implemented (Subp : Entity_Id) is
9956 Iface_Alias : constant Entity_Id := Interface_Alias (Subp);
9957 Impl_Kind : constant Name_Id := Implementation_Kind (Iface_Alias);
9958 Subp_Alias : constant Entity_Id := Alias (Subp);
9959 Contr_Typ : Entity_Id;
9960 Impl_Subp : Entity_Id;
9963 -- Subp must have an alias since it is a hidden entity used to link
9964 -- an interface subprogram to its overriding counterpart.
9966 pragma Assert (Present (Subp_Alias));
9968 -- Handle aliases to synchronized wrappers
9970 Impl_Subp := Subp_Alias;
9972 if Is_Primitive_Wrapper (Impl_Subp) then
9973 Impl_Subp := Wrapped_Entity (Impl_Subp);
9976 -- Extract the type of the controlling formal
9978 Contr_Typ := Etype (First_Formal (Subp_Alias));
9980 if Is_Concurrent_Record_Type (Contr_Typ) then
9981 Contr_Typ := Corresponding_Concurrent_Type (Contr_Typ);
9984 -- An interface subprogram whose implementation kind is By_Entry must
9985 -- be implemented by an entry.
9987 if Impl_Kind = Name_By_Entry
9988 and then Ekind (Impl_Subp) /= E_Entry
9990 Error_Msg_Node_2 := Iface_Alias;
9992 ("type & must implement abstract subprogram & with an entry",
9993 Subp_Alias, Contr_Typ);
9995 elsif Impl_Kind = Name_By_Protected_Procedure then
9997 -- An interface subprogram whose implementation kind is By_
9998 -- Protected_Procedure cannot be implemented by a primitive
9999 -- procedure of a task type.
10001 if Ekind (Contr_Typ) /= E_Protected_Type then
10002 Error_Msg_Node_2 := Contr_Typ;
10004 ("interface subprogram & cannot be implemented by a " &
10005 "primitive procedure of task type &", Subp_Alias,
10008 -- An interface subprogram whose implementation kind is By_
10009 -- Protected_Procedure must be implemented by a procedure.
10011 elsif Ekind (Impl_Subp) /= E_Procedure then
10012 Error_Msg_Node_2 := Iface_Alias;
10014 ("type & must implement abstract subprogram & with a " &
10015 "procedure", Subp_Alias, Contr_Typ);
10017 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
10018 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
10020 Error_Msg_Name_1 := Impl_Kind;
10022 ("overriding operation& must have synchronization%",
10026 -- If primitive has Optional synchronization, overriding operation
10027 -- must match if it has an explicit synchronization..
10029 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
10030 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
10032 Error_Msg_Name_1 := Impl_Kind;
10034 ("overriding operation& must have syncrhonization%",
10037 end Check_Pragma_Implemented;
10039 ------------------------------
10040 -- Check_Pragma_Implemented --
10041 ------------------------------
10043 procedure Check_Pragma_Implemented
10045 Iface_Subp : Entity_Id)
10047 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
10048 Subp_Kind : constant Name_Id := Implementation_Kind (Subp);
10051 -- Ada 2012 (AI05-0030): The implementation kinds of an overridden
10052 -- and overriding subprogram are different. In general this is an
10053 -- error except when the implementation kind of the overridden
10054 -- subprograms is By_Any or Optional.
10056 if Iface_Kind /= Subp_Kind
10057 and then Iface_Kind /= Name_By_Any
10058 and then Iface_Kind /= Name_Optional
10060 if Iface_Kind = Name_By_Entry then
10062 ("incompatible implementation kind, overridden subprogram " &
10063 "is marked By_Entry", Subp);
10066 ("incompatible implementation kind, overridden subprogram " &
10067 "is marked By_Protected_Procedure", Subp);
10070 end Check_Pragma_Implemented;
10072 --------------------------------
10073 -- Inherit_Pragma_Implemented --
10074 --------------------------------
10076 procedure Inherit_Pragma_Implemented
10078 Iface_Subp : Entity_Id)
10080 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
10081 Loc : constant Source_Ptr := Sloc (Subp);
10082 Impl_Prag : Node_Id;
10085 -- Since the implementation kind is stored as a representation item
10086 -- rather than a flag, create a pragma node.
10090 Chars => Name_Implemented,
10091 Pragma_Argument_Associations => New_List (
10092 Make_Pragma_Argument_Association (Loc,
10093 Expression => New_Occurrence_Of (Subp, Loc)),
10095 Make_Pragma_Argument_Association (Loc,
10096 Expression => Make_Identifier (Loc, Iface_Kind))));
10098 -- The pragma doesn't need to be analyzed because it is internally
10099 -- built. It is safe to directly register it as a rep item since we
10100 -- are only interested in the characters of the implementation kind.
10102 Record_Rep_Item (Subp, Impl_Prag);
10103 end Inherit_Pragma_Implemented;
10105 -- Start of processing for Check_Abstract_Overriding
10108 Op_List := Primitive_Operations (T);
10110 -- Loop to check primitive operations
10112 Elmt := First_Elmt (Op_List);
10113 while Present (Elmt) loop
10114 Subp := Node (Elmt);
10115 Alias_Subp := Alias (Subp);
10117 -- Inherited subprograms are identified by the fact that they do not
10118 -- come from source, and the associated source location is the
10119 -- location of the first subtype of the derived type.
10121 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
10122 -- subprograms that "require overriding".
10124 -- Special exception, do not complain about failure to override the
10125 -- stream routines _Input and _Output, as well as the primitive
10126 -- operations used in dispatching selects since we always provide
10127 -- automatic overridings for these subprograms.
10129 -- The partial view of T may have been a private extension, for
10130 -- which inherited functions dispatching on result are abstract.
10131 -- If the full view is a null extension, there is no need for
10132 -- overriding in Ada 2005, but wrappers need to be built for them
10133 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
10135 if Is_Null_Extension (T)
10136 and then Has_Controlling_Result (Subp)
10137 and then Ada_Version >= Ada_2005
10138 and then Present (Alias_Subp)
10139 and then not Comes_From_Source (Subp)
10140 and then not Is_Abstract_Subprogram (Alias_Subp)
10141 and then not Is_Access_Type (Etype (Subp))
10145 -- Ada 2005 (AI-251): Internal entities of interfaces need no
10146 -- processing because this check is done with the aliased
10149 elsif Present (Interface_Alias (Subp)) then
10152 elsif (Is_Abstract_Subprogram (Subp)
10153 or else Requires_Overriding (Subp)
10155 (Has_Controlling_Result (Subp)
10156 and then Present (Alias_Subp)
10157 and then not Comes_From_Source (Subp)
10158 and then Sloc (Subp) = Sloc (First_Subtype (T))))
10159 and then not Is_TSS (Subp, TSS_Stream_Input)
10160 and then not Is_TSS (Subp, TSS_Stream_Output)
10161 and then not Is_Abstract_Type (T)
10162 and then not Is_Predefined_Interface_Primitive (Subp)
10164 -- Ada 2005 (AI-251): Do not consider hidden entities associated
10165 -- with abstract interface types because the check will be done
10166 -- with the aliased entity (otherwise we generate a duplicated
10169 and then not Present (Interface_Alias (Subp))
10171 if Present (Alias_Subp) then
10173 -- Only perform the check for a derived subprogram when the
10174 -- type has an explicit record extension. This avoids incorrect
10175 -- flagging of abstract subprograms for the case of a type
10176 -- without an extension that is derived from a formal type
10177 -- with a tagged actual (can occur within a private part).
10179 -- Ada 2005 (AI-391): In the case of an inherited function with
10180 -- a controlling result of the type, the rule does not apply if
10181 -- the type is a null extension (unless the parent function
10182 -- itself is abstract, in which case the function must still be
10183 -- be overridden). The expander will generate an overriding
10184 -- wrapper function calling the parent subprogram (see
10185 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
10187 Type_Def := Type_Definition (Parent (T));
10189 if Nkind (Type_Def) = N_Derived_Type_Definition
10190 and then Present (Record_Extension_Part (Type_Def))
10192 (Ada_Version < Ada_2005
10193 or else not Is_Null_Extension (T)
10194 or else Ekind (Subp) = E_Procedure
10195 or else not Has_Controlling_Result (Subp)
10196 or else Is_Abstract_Subprogram (Alias_Subp)
10197 or else Requires_Overriding (Subp)
10198 or else Is_Access_Type (Etype (Subp)))
10200 -- Avoid reporting error in case of abstract predefined
10201 -- primitive inherited from interface type because the
10202 -- body of internally generated predefined primitives
10203 -- of tagged types are generated later by Freeze_Type
10205 if Is_Interface (Root_Type (T))
10206 and then Is_Abstract_Subprogram (Subp)
10207 and then Is_Predefined_Dispatching_Operation (Subp)
10208 and then not Comes_From_Source (Ultimate_Alias (Subp))
10212 -- A null extension is not obliged to override an inherited
10213 -- procedure subject to pragma Extensions_Visible with value
10214 -- False and at least one controlling OUT parameter
10215 -- (SPARK RM 6.1.7(6)).
10217 elsif Is_Null_Extension (T)
10218 and then Is_EVF_Procedure (Subp)
10224 ("type must be declared abstract or & overridden",
10227 -- Traverse the whole chain of aliased subprograms to
10228 -- complete the error notification. This is especially
10229 -- useful for traceability of the chain of entities when
10230 -- the subprogram corresponds with an interface
10231 -- subprogram (which may be defined in another package).
10233 if Present (Alias_Subp) then
10239 while Present (Alias (E)) loop
10241 -- Avoid reporting redundant errors on entities
10242 -- inherited from interfaces
10244 if Sloc (E) /= Sloc (T) then
10245 Error_Msg_Sloc := Sloc (E);
10247 ("\& has been inherited #", T, Subp);
10253 Error_Msg_Sloc := Sloc (E);
10255 -- AI05-0068: report if there is an overriding
10256 -- non-abstract subprogram that is invisible.
10259 and then not Is_Abstract_Subprogram (E)
10262 ("\& subprogram# is not visible",
10265 -- Clarify the case where a non-null extension must
10266 -- override inherited procedure subject to pragma
10267 -- Extensions_Visible with value False and at least
10268 -- one controlling OUT param.
10270 elsif Is_EVF_Procedure (E) then
10272 ("\& # is subject to Extensions_Visible False",
10277 ("\& has been inherited from subprogram #",
10284 -- Ada 2005 (AI-345): Protected or task type implementing
10285 -- abstract interfaces.
10287 elsif Is_Concurrent_Record_Type (T)
10288 and then Present (Interfaces (T))
10290 -- There is no need to check here RM 9.4(11.9/3) since we
10291 -- are processing the corresponding record type and the
10292 -- mode of the overriding subprograms was verified by
10293 -- Check_Conformance when the corresponding concurrent
10294 -- type declaration was analyzed.
10297 ("interface subprogram & must be overridden", T, Subp);
10299 -- Examine primitive operations of synchronized type to find
10300 -- homonyms that have the wrong profile.
10306 Prim := First_Entity (Corresponding_Concurrent_Type (T));
10307 while Present (Prim) loop
10308 if Chars (Prim) = Chars (Subp) then
10310 ("profile is not type conformant with prefixed "
10311 & "view profile of inherited operation&",
10315 Next_Entity (Prim);
10321 Error_Msg_Node_2 := T;
10323 ("abstract subprogram& not allowed for type&", Subp);
10325 -- Also post unconditional warning on the type (unconditional
10326 -- so that if there are more than one of these cases, we get
10327 -- them all, and not just the first one).
10329 Error_Msg_Node_2 := Subp;
10330 Error_Msg_N ("nonabstract type& has abstract subprogram&!", T);
10333 -- A subprogram subject to pragma Extensions_Visible with value
10334 -- "True" cannot override a subprogram subject to the same pragma
10335 -- with value "False" (SPARK RM 6.1.7(5)).
10337 elsif Extensions_Visible_Status (Subp) = Extensions_Visible_True
10338 and then Present (Overridden_Operation (Subp))
10339 and then Extensions_Visible_Status (Overridden_Operation (Subp)) =
10340 Extensions_Visible_False
10342 Error_Msg_Sloc := Sloc (Overridden_Operation (Subp));
10344 ("subprogram & with Extensions_Visible True cannot override "
10345 & "subprogram # with Extensions_Visible False", Subp);
10348 -- Ada 2012 (AI05-0030): Perform checks related to pragma Implemented
10350 -- Subp is an expander-generated procedure which maps an interface
10351 -- alias to a protected wrapper. The interface alias is flagged by
10352 -- pragma Implemented. Ensure that Subp is a procedure when the
10353 -- implementation kind is By_Protected_Procedure or an entry when
10356 if Ada_Version >= Ada_2012
10357 and then Is_Hidden (Subp)
10358 and then Present (Interface_Alias (Subp))
10359 and then Has_Rep_Pragma (Interface_Alias (Subp), Name_Implemented)
10361 Check_Pragma_Implemented (Subp);
10364 -- Subp is an interface primitive which overrides another interface
10365 -- primitive marked with pragma Implemented.
10367 if Ada_Version >= Ada_2012
10368 and then Present (Overridden_Operation (Subp))
10369 and then Has_Rep_Pragma
10370 (Overridden_Operation (Subp), Name_Implemented)
10372 -- If the overriding routine is also marked by Implemented, check
10373 -- that the two implementation kinds are conforming.
10375 if Has_Rep_Pragma (Subp, Name_Implemented) then
10376 Check_Pragma_Implemented
10378 Iface_Subp => Overridden_Operation (Subp));
10380 -- Otherwise the overriding routine inherits the implementation
10381 -- kind from the overridden subprogram.
10384 Inherit_Pragma_Implemented
10386 Iface_Subp => Overridden_Operation (Subp));
10390 -- If the operation is a wrapper for a synchronized primitive, it
10391 -- may be called indirectly through a dispatching select. We assume
10392 -- that it will be referenced elsewhere indirectly, and suppress
10393 -- warnings about an unused entity.
10395 if Is_Primitive_Wrapper (Subp)
10396 and then Present (Wrapped_Entity (Subp))
10398 Set_Referenced (Wrapped_Entity (Subp));
10403 end Check_Abstract_Overriding;
10405 ------------------------------------------------
10406 -- Check_Access_Discriminant_Requires_Limited --
10407 ------------------------------------------------
10409 procedure Check_Access_Discriminant_Requires_Limited
10414 -- A discriminant_specification for an access discriminant shall appear
10415 -- only in the declaration for a task or protected type, or for a type
10416 -- with the reserved word 'limited' in its definition or in one of its
10417 -- ancestors (RM 3.7(10)).
10419 -- AI-0063: The proper condition is that type must be immutably limited,
10420 -- or else be a partial view.
10422 if Nkind (Discriminant_Type (D)) = N_Access_Definition then
10423 if Is_Limited_View (Current_Scope)
10425 (Nkind (Parent (Current_Scope)) = N_Private_Type_Declaration
10426 and then Limited_Present (Parent (Current_Scope)))
10432 ("access discriminants allowed only for limited types", Loc);
10435 end Check_Access_Discriminant_Requires_Limited;
10437 -----------------------------------
10438 -- Check_Aliased_Component_Types --
10439 -----------------------------------
10441 procedure Check_Aliased_Component_Types (T : Entity_Id) is
10445 -- ??? Also need to check components of record extensions, but not
10446 -- components of protected types (which are always limited).
10448 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
10449 -- types to be unconstrained. This is safe because it is illegal to
10450 -- create access subtypes to such types with explicit discriminant
10453 if not Is_Limited_Type (T) then
10454 if Ekind (T) = E_Record_Type then
10455 C := First_Component (T);
10456 while Present (C) loop
10458 and then Has_Discriminants (Etype (C))
10459 and then not Is_Constrained (Etype (C))
10460 and then not In_Instance_Body
10461 and then Ada_Version < Ada_2005
10464 ("aliased component must be constrained (RM 3.6(11))",
10468 Next_Component (C);
10471 elsif Ekind (T) = E_Array_Type then
10472 if Has_Aliased_Components (T)
10473 and then Has_Discriminants (Component_Type (T))
10474 and then not Is_Constrained (Component_Type (T))
10475 and then not In_Instance_Body
10476 and then Ada_Version < Ada_2005
10479 ("aliased component type must be constrained (RM 3.6(11))",
10484 end Check_Aliased_Component_Types;
10486 ---------------------------------------
10487 -- Check_Anonymous_Access_Components --
10488 ---------------------------------------
10490 procedure Check_Anonymous_Access_Components
10491 (Typ_Decl : Node_Id;
10494 Comp_List : Node_Id)
10496 Loc : constant Source_Ptr := Sloc (Typ_Decl);
10497 Anon_Access : Entity_Id;
10500 Comp_Def : Node_Id;
10502 Type_Def : Node_Id;
10504 procedure Build_Incomplete_Type_Declaration;
10505 -- If the record type contains components that include an access to the
10506 -- current record, then create an incomplete type declaration for the
10507 -- record, to be used as the designated type of the anonymous access.
10508 -- This is done only once, and only if there is no previous partial
10509 -- view of the type.
10511 function Designates_T (Subt : Node_Id) return Boolean;
10512 -- Check whether a node designates the enclosing record type, or 'Class
10515 function Mentions_T (Acc_Def : Node_Id) return Boolean;
10516 -- Check whether an access definition includes a reference to
10517 -- the enclosing record type. The reference can be a subtype mark
10518 -- in the access definition itself, a 'Class attribute reference, or
10519 -- recursively a reference appearing in a parameter specification
10520 -- or result definition of an access_to_subprogram definition.
10522 --------------------------------------
10523 -- Build_Incomplete_Type_Declaration --
10524 --------------------------------------
10526 procedure Build_Incomplete_Type_Declaration is
10531 -- Is_Tagged indicates whether the type is tagged. It is tagged if
10532 -- it's "is new ... with record" or else "is tagged record ...".
10534 Is_Tagged : constant Boolean :=
10535 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
10537 Present (Record_Extension_Part (Type_Definition (Typ_Decl))))
10539 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
10540 and then Tagged_Present (Type_Definition (Typ_Decl)));
10543 -- If there is a previous partial view, no need to create a new one
10544 -- If the partial view, given by Prev, is incomplete, If Prev is
10545 -- a private declaration, full declaration is flagged accordingly.
10547 if Prev /= Typ then
10549 Make_Class_Wide_Type (Prev);
10550 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
10551 Set_Etype (Class_Wide_Type (Typ), Typ);
10556 elsif Has_Private_Declaration (Typ) then
10558 -- If we refer to T'Class inside T, and T is the completion of a
10559 -- private type, then make sure the class-wide type exists.
10562 Make_Class_Wide_Type (Typ);
10567 -- If there was a previous anonymous access type, the incomplete
10568 -- type declaration will have been created already.
10570 elsif Present (Current_Entity (Typ))
10571 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
10572 and then Full_View (Current_Entity (Typ)) = Typ
10575 and then Comes_From_Source (Current_Entity (Typ))
10576 and then not Is_Tagged_Type (Current_Entity (Typ))
10578 Make_Class_Wide_Type (Typ);
10580 ("incomplete view of tagged type should be declared tagged??",
10581 Parent (Current_Entity (Typ)));
10586 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
10587 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
10589 -- Type has already been inserted into the current scope. Remove
10590 -- it, and add incomplete declaration for type, so that subsequent
10591 -- anonymous access types can use it. The entity is unchained from
10592 -- the homonym list and from immediate visibility. After analysis,
10593 -- the entity in the incomplete declaration becomes immediately
10594 -- visible in the record declaration that follows.
10596 H := Current_Entity (Typ);
10599 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
10602 and then Homonym (H) /= Typ
10604 H := Homonym (Typ);
10607 Set_Homonym (H, Homonym (Typ));
10610 Insert_Before (Typ_Decl, Decl);
10612 Set_Full_View (Inc_T, Typ);
10616 -- Create a common class-wide type for both views, and set the
10617 -- Etype of the class-wide type to the full view.
10619 Make_Class_Wide_Type (Inc_T);
10620 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
10621 Set_Etype (Class_Wide_Type (Typ), Typ);
10624 end Build_Incomplete_Type_Declaration;
10630 function Designates_T (Subt : Node_Id) return Boolean is
10631 Type_Id : constant Name_Id := Chars (Typ);
10633 function Names_T (Nam : Node_Id) return Boolean;
10634 -- The record type has not been introduced in the current scope
10635 -- yet, so we must examine the name of the type itself, either
10636 -- an identifier T, or an expanded name of the form P.T, where
10637 -- P denotes the current scope.
10643 function Names_T (Nam : Node_Id) return Boolean is
10645 if Nkind (Nam) = N_Identifier then
10646 return Chars (Nam) = Type_Id;
10648 elsif Nkind (Nam) = N_Selected_Component then
10649 if Chars (Selector_Name (Nam)) = Type_Id then
10650 if Nkind (Prefix (Nam)) = N_Identifier then
10651 return Chars (Prefix (Nam)) = Chars (Current_Scope);
10653 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
10654 return Chars (Selector_Name (Prefix (Nam))) =
10655 Chars (Current_Scope);
10669 -- Start of processing for Designates_T
10672 if Nkind (Subt) = N_Identifier then
10673 return Chars (Subt) = Type_Id;
10675 -- Reference can be through an expanded name which has not been
10676 -- analyzed yet, and which designates enclosing scopes.
10678 elsif Nkind (Subt) = N_Selected_Component then
10679 if Names_T (Subt) then
10682 -- Otherwise it must denote an entity that is already visible.
10683 -- The access definition may name a subtype of the enclosing
10684 -- type, if there is a previous incomplete declaration for it.
10687 Find_Selected_Component (Subt);
10689 Is_Entity_Name (Subt)
10690 and then Scope (Entity (Subt)) = Current_Scope
10692 (Chars (Base_Type (Entity (Subt))) = Type_Id
10694 (Is_Class_Wide_Type (Entity (Subt))
10696 Chars (Etype (Base_Type (Entity (Subt)))) =
10700 -- A reference to the current type may appear as the prefix of
10701 -- a 'Class attribute.
10703 elsif Nkind (Subt) = N_Attribute_Reference
10704 and then Attribute_Name (Subt) = Name_Class
10706 return Names_T (Prefix (Subt));
10717 function Mentions_T (Acc_Def : Node_Id) return Boolean is
10718 Param_Spec : Node_Id;
10720 Acc_Subprg : constant Node_Id :=
10721 Access_To_Subprogram_Definition (Acc_Def);
10724 if No (Acc_Subprg) then
10725 return Designates_T (Subtype_Mark (Acc_Def));
10728 -- Component is an access_to_subprogram: examine its formals,
10729 -- and result definition in the case of an access_to_function.
10731 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
10732 while Present (Param_Spec) loop
10733 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
10734 and then Mentions_T (Parameter_Type (Param_Spec))
10738 elsif Designates_T (Parameter_Type (Param_Spec)) then
10745 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
10746 if Nkind (Result_Definition (Acc_Subprg)) =
10747 N_Access_Definition
10749 return Mentions_T (Result_Definition (Acc_Subprg));
10751 return Designates_T (Result_Definition (Acc_Subprg));
10758 -- Start of processing for Check_Anonymous_Access_Components
10761 if No (Comp_List) then
10765 Comp := First (Component_Items (Comp_List));
10766 while Present (Comp) loop
10767 if Nkind (Comp) = N_Component_Declaration
10769 (Access_Definition (Component_Definition (Comp)))
10771 Mentions_T (Access_Definition (Component_Definition (Comp)))
10773 Comp_Def := Component_Definition (Comp);
10775 Access_To_Subprogram_Definition (Access_Definition (Comp_Def));
10777 Build_Incomplete_Type_Declaration;
10778 Anon_Access := Make_Temporary (Loc, 'S');
10780 -- Create a declaration for the anonymous access type: either
10781 -- an access_to_object or an access_to_subprogram.
10783 if Present (Acc_Def) then
10784 if Nkind (Acc_Def) = N_Access_Function_Definition then
10786 Make_Access_Function_Definition (Loc,
10787 Parameter_Specifications =>
10788 Parameter_Specifications (Acc_Def),
10789 Result_Definition => Result_Definition (Acc_Def));
10792 Make_Access_Procedure_Definition (Loc,
10793 Parameter_Specifications =>
10794 Parameter_Specifications (Acc_Def));
10799 Make_Access_To_Object_Definition (Loc,
10800 Subtype_Indication =>
10802 (Subtype_Mark (Access_Definition (Comp_Def))));
10804 Set_Constant_Present
10805 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
10807 (Type_Def, All_Present (Access_Definition (Comp_Def)));
10810 Set_Null_Exclusion_Present
10812 Null_Exclusion_Present (Access_Definition (Comp_Def)));
10815 Make_Full_Type_Declaration (Loc,
10816 Defining_Identifier => Anon_Access,
10817 Type_Definition => Type_Def);
10819 Insert_Before (Typ_Decl, Decl);
10822 -- If an access to subprogram, create the extra formals
10824 if Present (Acc_Def) then
10825 Create_Extra_Formals (Designated_Type (Anon_Access));
10827 -- If an access to object, preserve entity of designated type,
10828 -- for ASIS use, before rewriting the component definition.
10835 Desig := Entity (Subtype_Indication (Type_Def));
10837 -- If the access definition is to the current record,
10838 -- the visible entity at this point is an incomplete
10839 -- type. Retrieve the full view to simplify ASIS queries
10841 if Ekind (Desig) = E_Incomplete_Type then
10842 Desig := Full_View (Desig);
10846 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
10851 Make_Component_Definition (Loc,
10852 Subtype_Indication =>
10853 New_Occurrence_Of (Anon_Access, Loc)));
10855 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
10856 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
10858 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
10861 Set_Is_Local_Anonymous_Access (Anon_Access);
10867 if Present (Variant_Part (Comp_List)) then
10871 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
10872 while Present (V) loop
10873 Check_Anonymous_Access_Components
10874 (Typ_Decl, Typ, Prev, Component_List (V));
10875 Next_Non_Pragma (V);
10879 end Check_Anonymous_Access_Components;
10881 ----------------------
10882 -- Check_Completion --
10883 ----------------------
10885 procedure Check_Completion (Body_Id : Node_Id := Empty) is
10888 procedure Post_Error;
10889 -- Post error message for lack of completion for entity E
10895 procedure Post_Error is
10896 procedure Missing_Body;
10897 -- Output missing body message
10903 procedure Missing_Body is
10905 -- Spec is in same unit, so we can post on spec
10907 if In_Same_Source_Unit (Body_Id, E) then
10908 Error_Msg_N ("missing body for &", E);
10910 -- Spec is in a separate unit, so we have to post on the body
10913 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
10917 -- Start of processing for Post_Error
10920 if not Comes_From_Source (E) then
10921 if Ekind_In (E, E_Task_Type, E_Protected_Type) then
10923 -- It may be an anonymous protected type created for a
10924 -- single variable. Post error on variable, if present.
10930 Var := First_Entity (Current_Scope);
10931 while Present (Var) loop
10932 exit when Etype (Var) = E
10933 and then Comes_From_Source (Var);
10938 if Present (Var) then
10945 -- If a generated entity has no completion, then either previous
10946 -- semantic errors have disabled the expansion phase, or else we had
10947 -- missing subunits, or else we are compiling without expansion,
10948 -- or else something is very wrong.
10950 if not Comes_From_Source (E) then
10952 (Serious_Errors_Detected > 0
10953 or else Configurable_Run_Time_Violations > 0
10954 or else Subunits_Missing
10955 or else not Expander_Active);
10958 -- Here for source entity
10961 -- Here if no body to post the error message, so we post the error
10962 -- on the declaration that has no completion. This is not really
10963 -- the right place to post it, think about this later ???
10965 if No (Body_Id) then
10966 if Is_Type (E) then
10968 ("missing full declaration for }", Parent (E), E);
10970 Error_Msg_NE ("missing body for &", Parent (E), E);
10973 -- Package body has no completion for a declaration that appears
10974 -- in the corresponding spec. Post error on the body, with a
10975 -- reference to the non-completed declaration.
10978 Error_Msg_Sloc := Sloc (E);
10980 if Is_Type (E) then
10981 Error_Msg_NE ("missing full declaration for }!", Body_Id, E);
10983 elsif Is_Overloadable (E)
10984 and then Current_Entity_In_Scope (E) /= E
10986 -- It may be that the completion is mistyped and appears as
10987 -- a distinct overloading of the entity.
10990 Candidate : constant Entity_Id :=
10991 Current_Entity_In_Scope (E);
10992 Decl : constant Node_Id :=
10993 Unit_Declaration_Node (Candidate);
10996 if Is_Overloadable (Candidate)
10997 and then Ekind (Candidate) = Ekind (E)
10998 and then Nkind (Decl) = N_Subprogram_Body
10999 and then Acts_As_Spec (Decl)
11001 Check_Type_Conformant (Candidate, E);
11017 Pack_Id : constant Entity_Id := Current_Scope;
11019 -- Start of processing for Check_Completion
11022 E := First_Entity (Pack_Id);
11023 while Present (E) loop
11024 if Is_Intrinsic_Subprogram (E) then
11027 -- The following situation requires special handling: a child unit
11028 -- that appears in the context clause of the body of its parent:
11030 -- procedure Parent.Child (...);
11032 -- with Parent.Child;
11033 -- package body Parent is
11035 -- Here Parent.Child appears as a local entity, but should not be
11036 -- flagged as requiring completion, because it is a compilation
11039 -- Ignore missing completion for a subprogram that does not come from
11040 -- source (including the _Call primitive operation of RAS types,
11041 -- which has to have the flag Comes_From_Source for other purposes):
11042 -- we assume that the expander will provide the missing completion.
11043 -- In case of previous errors, other expansion actions that provide
11044 -- bodies for null procedures with not be invoked, so inhibit message
11047 -- Note that E_Operator is not in the list that follows, because
11048 -- this kind is reserved for predefined operators, that are
11049 -- intrinsic and do not need completion.
11051 elsif Ekind_In (E, E_Function,
11053 E_Generic_Function,
11054 E_Generic_Procedure)
11056 if Has_Completion (E) then
11059 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
11062 elsif Is_Subprogram (E)
11063 and then (not Comes_From_Source (E)
11064 or else Chars (E) = Name_uCall)
11069 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
11073 elsif Nkind (Parent (E)) = N_Procedure_Specification
11074 and then Null_Present (Parent (E))
11075 and then Serious_Errors_Detected > 0
11083 elsif Is_Entry (E) then
11084 if not Has_Completion (E) and then
11085 (Ekind (Scope (E)) = E_Protected_Object
11086 or else Ekind (Scope (E)) = E_Protected_Type)
11091 elsif Is_Package_Or_Generic_Package (E) then
11092 if Unit_Requires_Body (E) then
11093 if not Has_Completion (E)
11094 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
11100 elsif not Is_Child_Unit (E) then
11101 May_Need_Implicit_Body (E);
11104 -- A formal incomplete type (Ada 2012) does not require a completion;
11105 -- other incomplete type declarations do.
11107 elsif Ekind (E) = E_Incomplete_Type
11108 and then No (Underlying_Type (E))
11109 and then not Is_Generic_Type (E)
11113 elsif Ekind_In (E, E_Task_Type, E_Protected_Type)
11114 and then not Has_Completion (E)
11118 -- A single task declared in the current scope is a constant, verify
11119 -- that the body of its anonymous type is in the same scope. If the
11120 -- task is defined elsewhere, this may be a renaming declaration for
11121 -- which no completion is needed.
11123 elsif Ekind (E) = E_Constant
11124 and then Ekind (Etype (E)) = E_Task_Type
11125 and then not Has_Completion (Etype (E))
11126 and then Scope (Etype (E)) = Current_Scope
11130 elsif Ekind (E) = E_Protected_Object
11131 and then not Has_Completion (Etype (E))
11135 elsif Ekind (E) = E_Record_Type then
11136 if Is_Tagged_Type (E) then
11137 Check_Abstract_Overriding (E);
11138 Check_Conventions (E);
11141 Check_Aliased_Component_Types (E);
11143 elsif Ekind (E) = E_Array_Type then
11144 Check_Aliased_Component_Types (E);
11150 end Check_Completion;
11152 ------------------------------------
11153 -- Check_CPP_Type_Has_No_Defaults --
11154 ------------------------------------
11156 procedure Check_CPP_Type_Has_No_Defaults (T : Entity_Id) is
11157 Tdef : constant Node_Id := Type_Definition (Declaration_Node (T));
11162 -- Obtain the component list
11164 if Nkind (Tdef) = N_Record_Definition then
11165 Clist := Component_List (Tdef);
11166 else pragma Assert (Nkind (Tdef) = N_Derived_Type_Definition);
11167 Clist := Component_List (Record_Extension_Part (Tdef));
11170 -- Check all components to ensure no default expressions
11172 if Present (Clist) then
11173 Comp := First (Component_Items (Clist));
11174 while Present (Comp) loop
11175 if Present (Expression (Comp)) then
11177 ("component of imported 'C'P'P type cannot have "
11178 & "default expression", Expression (Comp));
11184 end Check_CPP_Type_Has_No_Defaults;
11186 ----------------------------
11187 -- Check_Delta_Expression --
11188 ----------------------------
11190 procedure Check_Delta_Expression (E : Node_Id) is
11192 if not (Is_Real_Type (Etype (E))) then
11193 Wrong_Type (E, Any_Real);
11195 elsif not Is_OK_Static_Expression (E) then
11196 Flag_Non_Static_Expr
11197 ("non-static expression used for delta value!", E);
11199 elsif not UR_Is_Positive (Expr_Value_R (E)) then
11200 Error_Msg_N ("delta expression must be positive", E);
11206 -- If any of above errors occurred, then replace the incorrect
11207 -- expression by the real 0.1, which should prevent further errors.
11210 Make_Real_Literal (Sloc (E), Ureal_Tenth));
11211 Analyze_And_Resolve (E, Standard_Float);
11212 end Check_Delta_Expression;
11214 -----------------------------
11215 -- Check_Digits_Expression --
11216 -----------------------------
11218 procedure Check_Digits_Expression (E : Node_Id) is
11220 if not (Is_Integer_Type (Etype (E))) then
11221 Wrong_Type (E, Any_Integer);
11223 elsif not Is_OK_Static_Expression (E) then
11224 Flag_Non_Static_Expr
11225 ("non-static expression used for digits value!", E);
11227 elsif Expr_Value (E) <= 0 then
11228 Error_Msg_N ("digits value must be greater than zero", E);
11234 -- If any of above errors occurred, then replace the incorrect
11235 -- expression by the integer 1, which should prevent further errors.
11237 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
11238 Analyze_And_Resolve (E, Standard_Integer);
11240 end Check_Digits_Expression;
11242 --------------------------
11243 -- Check_Initialization --
11244 --------------------------
11246 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
11248 -- Special processing for limited types
11250 if Is_Limited_Type (T)
11251 and then not In_Instance
11252 and then not In_Inlined_Body
11254 if not OK_For_Limited_Init (T, Exp) then
11256 -- In GNAT mode, this is just a warning, to allow it to be evilly
11257 -- turned off. Otherwise it is a real error.
11261 ("??cannot initialize entities of limited type!", Exp);
11263 elsif Ada_Version < Ada_2005 then
11265 -- The side effect removal machinery may generate illegal Ada
11266 -- code to avoid the usage of access types and 'reference in
11267 -- SPARK mode. Since this is legal code with respect to theorem
11268 -- proving, do not emit the error.
11271 and then Nkind (Exp) = N_Function_Call
11272 and then Nkind (Parent (Exp)) = N_Object_Declaration
11273 and then not Comes_From_Source
11274 (Defining_Identifier (Parent (Exp)))
11280 ("cannot initialize entities of limited type", Exp);
11281 Explain_Limited_Type (T, Exp);
11285 -- Specialize error message according to kind of illegal
11286 -- initial expression.
11288 if Nkind (Exp) = N_Type_Conversion
11289 and then Nkind (Expression (Exp)) = N_Function_Call
11292 ("illegal context for call"
11293 & " to function with limited result", Exp);
11297 ("initialization of limited object requires aggregate "
11298 & "or function call", Exp);
11304 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag gets
11305 -- set unless we can be sure that no range check is required.
11307 if (GNATprove_Mode or not Expander_Active)
11308 and then Is_Scalar_Type (T)
11309 and then not Is_In_Range (Exp, T, Assume_Valid => True)
11311 Set_Do_Range_Check (Exp);
11313 end Check_Initialization;
11315 ----------------------
11316 -- Check_Interfaces --
11317 ----------------------
11319 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
11320 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
11323 Iface_Def : Node_Id;
11324 Iface_Typ : Entity_Id;
11325 Parent_Node : Node_Id;
11327 Is_Task : Boolean := False;
11328 -- Set True if parent type or any progenitor is a task interface
11330 Is_Protected : Boolean := False;
11331 -- Set True if parent type or any progenitor is a protected interface
11333 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
11334 -- Check that a progenitor is compatible with declaration. If an error
11335 -- message is output, it is posted on Error_Node.
11341 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
11342 Iface_Id : constant Entity_Id :=
11343 Defining_Identifier (Parent (Iface_Def));
11344 Type_Def : Node_Id;
11347 if Nkind (N) = N_Private_Extension_Declaration then
11350 Type_Def := Type_Definition (N);
11353 if Is_Task_Interface (Iface_Id) then
11356 elsif Is_Protected_Interface (Iface_Id) then
11357 Is_Protected := True;
11360 if Is_Synchronized_Interface (Iface_Id) then
11362 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
11363 -- extension derived from a synchronized interface must explicitly
11364 -- be declared synchronized, because the full view will be a
11365 -- synchronized type.
11367 if Nkind (N) = N_Private_Extension_Declaration then
11368 if not Synchronized_Present (N) then
11370 ("private extension of& must be explicitly synchronized",
11374 -- However, by 3.9.4(16/2), a full type that is a record extension
11375 -- is never allowed to derive from a synchronized interface (note
11376 -- that interfaces must be excluded from this check, because those
11377 -- are represented by derived type definitions in some cases).
11379 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11380 and then not Interface_Present (Type_Definition (N))
11382 Error_Msg_N ("record extension cannot derive from synchronized "
11383 & "interface", Error_Node);
11387 -- Check that the characteristics of the progenitor are compatible
11388 -- with the explicit qualifier in the declaration.
11389 -- The check only applies to qualifiers that come from source.
11390 -- Limited_Present also appears in the declaration of corresponding
11391 -- records, and the check does not apply to them.
11393 if Limited_Present (Type_Def)
11395 Is_Concurrent_Record_Type (Defining_Identifier (N))
11397 if Is_Limited_Interface (Parent_Type)
11398 and then not Is_Limited_Interface (Iface_Id)
11401 ("progenitor & must be limited interface",
11402 Error_Node, Iface_Id);
11405 (Task_Present (Iface_Def)
11406 or else Protected_Present (Iface_Def)
11407 or else Synchronized_Present (Iface_Def))
11408 and then Nkind (N) /= N_Private_Extension_Declaration
11409 and then not Error_Posted (N)
11412 ("progenitor & must be limited interface",
11413 Error_Node, Iface_Id);
11416 -- Protected interfaces can only inherit from limited, synchronized
11417 -- or protected interfaces.
11419 elsif Nkind (N) = N_Full_Type_Declaration
11420 and then Protected_Present (Type_Def)
11422 if Limited_Present (Iface_Def)
11423 or else Synchronized_Present (Iface_Def)
11424 or else Protected_Present (Iface_Def)
11428 elsif Task_Present (Iface_Def) then
11429 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11430 & "from task interface", Error_Node);
11433 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11434 & "from non-limited interface", Error_Node);
11437 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
11438 -- limited and synchronized.
11440 elsif Synchronized_Present (Type_Def) then
11441 if Limited_Present (Iface_Def)
11442 or else Synchronized_Present (Iface_Def)
11446 elsif Protected_Present (Iface_Def)
11447 and then Nkind (N) /= N_Private_Extension_Declaration
11449 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11450 & "from protected interface", Error_Node);
11452 elsif Task_Present (Iface_Def)
11453 and then Nkind (N) /= N_Private_Extension_Declaration
11455 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11456 & "from task interface", Error_Node);
11458 elsif not Is_Limited_Interface (Iface_Id) then
11459 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11460 & "from non-limited interface", Error_Node);
11463 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
11464 -- synchronized or task interfaces.
11466 elsif Nkind (N) = N_Full_Type_Declaration
11467 and then Task_Present (Type_Def)
11469 if Limited_Present (Iface_Def)
11470 or else Synchronized_Present (Iface_Def)
11471 or else Task_Present (Iface_Def)
11475 elsif Protected_Present (Iface_Def) then
11476 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11477 & "protected interface", Error_Node);
11480 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11481 & "non-limited interface", Error_Node);
11486 -- Start of processing for Check_Interfaces
11489 if Is_Interface (Parent_Type) then
11490 if Is_Task_Interface (Parent_Type) then
11493 elsif Is_Protected_Interface (Parent_Type) then
11494 Is_Protected := True;
11498 if Nkind (N) = N_Private_Extension_Declaration then
11500 -- Check that progenitors are compatible with declaration
11502 Iface := First (Interface_List (Def));
11503 while Present (Iface) loop
11504 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11506 Parent_Node := Parent (Base_Type (Iface_Typ));
11507 Iface_Def := Type_Definition (Parent_Node);
11509 if not Is_Interface (Iface_Typ) then
11510 Diagnose_Interface (Iface, Iface_Typ);
11512 Check_Ifaces (Iface_Def, Iface);
11518 if Is_Task and Is_Protected then
11520 ("type cannot derive from task and protected interface", N);
11526 -- Full type declaration of derived type.
11527 -- Check compatibility with parent if it is interface type
11529 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11530 and then Is_Interface (Parent_Type)
11532 Parent_Node := Parent (Parent_Type);
11534 -- More detailed checks for interface varieties
11537 (Iface_Def => Type_Definition (Parent_Node),
11538 Error_Node => Subtype_Indication (Type_Definition (N)));
11541 Iface := First (Interface_List (Def));
11542 while Present (Iface) loop
11543 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11545 Parent_Node := Parent (Base_Type (Iface_Typ));
11546 Iface_Def := Type_Definition (Parent_Node);
11548 if not Is_Interface (Iface_Typ) then
11549 Diagnose_Interface (Iface, Iface_Typ);
11552 -- "The declaration of a specific descendant of an interface
11553 -- type freezes the interface type" RM 13.14
11555 Freeze_Before (N, Iface_Typ);
11556 Check_Ifaces (Iface_Def, Error_Node => Iface);
11562 if Is_Task and Is_Protected then
11564 ("type cannot derive from task and protected interface", N);
11566 end Check_Interfaces;
11568 ------------------------------------
11569 -- Check_Or_Process_Discriminants --
11570 ------------------------------------
11572 -- If an incomplete or private type declaration was already given for the
11573 -- type, the discriminants may have already been processed if they were
11574 -- present on the incomplete declaration. In this case a full conformance
11575 -- check has been performed in Find_Type_Name, and we then recheck here
11576 -- some properties that can't be checked on the partial view alone.
11577 -- Otherwise we call Process_Discriminants.
11579 procedure Check_Or_Process_Discriminants
11582 Prev : Entity_Id := Empty)
11585 if Has_Discriminants (T) then
11587 -- Discriminants are already set on T if they were already present
11588 -- on the partial view. Make them visible to component declarations.
11592 -- Discriminant on T (full view) referencing expr on partial view
11594 Prev_D : Entity_Id;
11595 -- Entity of corresponding discriminant on partial view
11598 -- Discriminant specification for full view, expression is
11599 -- the syntactic copy on full view (which has been checked for
11600 -- conformance with partial view), only used here to post error
11604 D := First_Discriminant (T);
11605 New_D := First (Discriminant_Specifications (N));
11606 while Present (D) loop
11607 Prev_D := Current_Entity (D);
11608 Set_Current_Entity (D);
11609 Set_Is_Immediately_Visible (D);
11610 Set_Homonym (D, Prev_D);
11612 -- Handle the case where there is an untagged partial view and
11613 -- the full view is tagged: must disallow discriminants with
11614 -- defaults, unless compiling for Ada 2012, which allows a
11615 -- limited tagged type to have defaulted discriminants (see
11616 -- AI05-0214). However, suppress error here if it was already
11617 -- reported on the default expression of the partial view.
11619 if Is_Tagged_Type (T)
11620 and then Present (Expression (Parent (D)))
11621 and then (not Is_Limited_Type (Current_Scope)
11622 or else Ada_Version < Ada_2012)
11623 and then not Error_Posted (Expression (Parent (D)))
11625 if Ada_Version >= Ada_2012 then
11627 ("discriminants of nonlimited tagged type cannot have "
11629 Expression (New_D));
11632 ("discriminants of tagged type cannot have defaults",
11633 Expression (New_D));
11637 -- Ada 2005 (AI-230): Access discriminant allowed in
11638 -- non-limited record types.
11640 if Ada_Version < Ada_2005 then
11642 -- This restriction gets applied to the full type here. It
11643 -- has already been applied earlier to the partial view.
11645 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
11648 Next_Discriminant (D);
11653 elsif Present (Discriminant_Specifications (N)) then
11654 Process_Discriminants (N, Prev);
11656 end Check_Or_Process_Discriminants;
11658 ----------------------
11659 -- Check_Real_Bound --
11660 ----------------------
11662 procedure Check_Real_Bound (Bound : Node_Id) is
11664 if not Is_Real_Type (Etype (Bound)) then
11666 ("bound in real type definition must be of real type", Bound);
11668 elsif not Is_OK_Static_Expression (Bound) then
11669 Flag_Non_Static_Expr
11670 ("non-static expression used for real type bound!", Bound);
11677 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
11679 Resolve (Bound, Standard_Float);
11680 end Check_Real_Bound;
11682 ------------------------------
11683 -- Complete_Private_Subtype --
11684 ------------------------------
11686 procedure Complete_Private_Subtype
11689 Full_Base : Entity_Id;
11690 Related_Nod : Node_Id)
11692 Save_Next_Entity : Entity_Id;
11693 Save_Homonym : Entity_Id;
11696 -- Set semantic attributes for (implicit) private subtype completion.
11697 -- If the full type has no discriminants, then it is a copy of the
11698 -- full view of the base. Otherwise, it is a subtype of the base with
11699 -- a possible discriminant constraint. Save and restore the original
11700 -- Next_Entity field of full to ensure that the calls to Copy_Node do
11701 -- not corrupt the entity chain.
11703 -- Note that the type of the full view is the same entity as the type
11704 -- of the partial view. In this fashion, the subtype has access to the
11705 -- correct view of the parent.
11707 Save_Next_Entity := Next_Entity (Full);
11708 Save_Homonym := Homonym (Priv);
11710 case Ekind (Full_Base) is
11711 when E_Record_Type |
11717 Copy_Node (Priv, Full);
11719 Set_Has_Discriminants
11720 (Full, Has_Discriminants (Full_Base));
11721 Set_Has_Unknown_Discriminants
11722 (Full, Has_Unknown_Discriminants (Full_Base));
11723 Set_First_Entity (Full, First_Entity (Full_Base));
11724 Set_Last_Entity (Full, Last_Entity (Full_Base));
11726 -- If the underlying base type is constrained, we know that the
11727 -- full view of the subtype is constrained as well (the converse
11728 -- is not necessarily true).
11730 if Is_Constrained (Full_Base) then
11731 Set_Is_Constrained (Full);
11735 Copy_Node (Full_Base, Full);
11737 Set_Chars (Full, Chars (Priv));
11738 Conditional_Delay (Full, Priv);
11739 Set_Sloc (Full, Sloc (Priv));
11742 Set_Next_Entity (Full, Save_Next_Entity);
11743 Set_Homonym (Full, Save_Homonym);
11744 Set_Associated_Node_For_Itype (Full, Related_Nod);
11746 -- Set common attributes for all subtypes: kind, convention, etc.
11748 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
11749 Set_Convention (Full, Convention (Full_Base));
11751 -- The Etype of the full view is inconsistent. Gigi needs to see the
11752 -- structural full view, which is what the current scheme gives: the
11753 -- Etype of the full view is the etype of the full base. However, if the
11754 -- full base is a derived type, the full view then looks like a subtype
11755 -- of the parent, not a subtype of the full base. If instead we write:
11757 -- Set_Etype (Full, Full_Base);
11759 -- then we get inconsistencies in the front-end (confusion between
11760 -- views). Several outstanding bugs are related to this ???
11762 Set_Is_First_Subtype (Full, False);
11763 Set_Scope (Full, Scope (Priv));
11764 Set_Size_Info (Full, Full_Base);
11765 Set_RM_Size (Full, RM_Size (Full_Base));
11766 Set_Is_Itype (Full);
11768 -- A subtype of a private-type-without-discriminants, whose full-view
11769 -- has discriminants with default expressions, is not constrained.
11771 if not Has_Discriminants (Priv) then
11772 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
11774 if Has_Discriminants (Full_Base) then
11775 Set_Discriminant_Constraint
11776 (Full, Discriminant_Constraint (Full_Base));
11778 -- The partial view may have been indefinite, the full view
11781 Set_Has_Unknown_Discriminants
11782 (Full, Has_Unknown_Discriminants (Full_Base));
11786 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
11787 Set_Depends_On_Private (Full, Has_Private_Component (Full));
11789 -- Freeze the private subtype entity if its parent is delayed, and not
11790 -- already frozen. We skip this processing if the type is an anonymous
11791 -- subtype of a record component, or is the corresponding record of a
11792 -- protected type, since these are processed when the enclosing type
11795 if not Is_Type (Scope (Full)) then
11796 Set_Has_Delayed_Freeze (Full,
11797 Has_Delayed_Freeze (Full_Base)
11798 and then (not Is_Frozen (Full_Base)));
11801 Set_Freeze_Node (Full, Empty);
11802 Set_Is_Frozen (Full, False);
11803 Set_Full_View (Priv, Full);
11805 if Has_Discriminants (Full) then
11806 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
11807 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
11809 if Has_Unknown_Discriminants (Full) then
11810 Set_Discriminant_Constraint (Full, No_Elist);
11814 if Ekind (Full_Base) = E_Record_Type
11815 and then Has_Discriminants (Full_Base)
11816 and then Has_Discriminants (Priv) -- might not, if errors
11817 and then not Has_Unknown_Discriminants (Priv)
11818 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
11820 Create_Constrained_Components
11821 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
11823 -- If the full base is itself derived from private, build a congruent
11824 -- subtype of its underlying type, for use by the back end. For a
11825 -- constrained record component, the declaration cannot be placed on
11826 -- the component list, but it must nevertheless be built an analyzed, to
11827 -- supply enough information for Gigi to compute the size of component.
11829 elsif Ekind (Full_Base) in Private_Kind
11830 and then Is_Derived_Type (Full_Base)
11831 and then Has_Discriminants (Full_Base)
11832 and then (Ekind (Current_Scope) /= E_Record_Subtype)
11834 if not Is_Itype (Priv)
11836 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
11838 Build_Underlying_Full_View
11839 (Parent (Priv), Full, Etype (Full_Base));
11841 elsif Nkind (Related_Nod) = N_Component_Declaration then
11842 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
11845 elsif Is_Record_Type (Full_Base) then
11847 -- Show Full is simply a renaming of Full_Base
11849 Set_Cloned_Subtype (Full, Full_Base);
11852 -- It is unsafe to share the bounds of a scalar type, because the Itype
11853 -- is elaborated on demand, and if a bound is non-static then different
11854 -- orders of elaboration in different units will lead to different
11855 -- external symbols.
11857 if Is_Scalar_Type (Full_Base) then
11858 Set_Scalar_Range (Full,
11859 Make_Range (Sloc (Related_Nod),
11861 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
11863 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
11865 -- This completion inherits the bounds of the full parent, but if
11866 -- the parent is an unconstrained floating point type, so is the
11869 if Is_Floating_Point_Type (Full_Base) then
11870 Set_Includes_Infinities
11871 (Scalar_Range (Full), Has_Infinities (Full_Base));
11875 -- ??? It seems that a lot of fields are missing that should be copied
11876 -- from Full_Base to Full. Here are some that are introduced in a
11877 -- non-disruptive way but a cleanup is necessary.
11879 if Is_Tagged_Type (Full_Base) then
11880 Set_Is_Tagged_Type (Full);
11881 Set_Direct_Primitive_Operations
11882 (Full, Direct_Primitive_Operations (Full_Base));
11883 Set_No_Tagged_Streams_Pragma
11884 (Full, No_Tagged_Streams_Pragma (Full_Base));
11886 -- Inherit class_wide type of full_base in case the partial view was
11887 -- not tagged. Otherwise it has already been created when the private
11888 -- subtype was analyzed.
11890 if No (Class_Wide_Type (Full)) then
11891 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
11894 -- If this is a subtype of a protected or task type, constrain its
11895 -- corresponding record, unless this is a subtype without constraints,
11896 -- i.e. a simple renaming as with an actual subtype in an instance.
11898 elsif Is_Concurrent_Type (Full_Base) then
11899 if Has_Discriminants (Full)
11900 and then Present (Corresponding_Record_Type (Full_Base))
11902 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
11904 Set_Corresponding_Record_Type (Full,
11905 Constrain_Corresponding_Record
11906 (Full, Corresponding_Record_Type (Full_Base), Related_Nod));
11909 Set_Corresponding_Record_Type (Full,
11910 Corresponding_Record_Type (Full_Base));
11914 -- Link rep item chain, and also setting of Has_Predicates from private
11915 -- subtype to full subtype, since we will need these on the full subtype
11916 -- to create the predicate function. Note that the full subtype may
11917 -- already have rep items, inherited from the full view of the base
11918 -- type, so we must be sure not to overwrite these entries.
11923 Next_Item : Node_Id;
11926 Item := First_Rep_Item (Full);
11928 -- If no existing rep items on full type, we can just link directly
11929 -- to the list of items on the private type, if any exist.. Same if
11930 -- the rep items are only those inherited from the base
11933 or else Nkind (Item) /= N_Aspect_Specification
11934 or else Entity (Item) = Full_Base)
11935 and then Present (First_Rep_Item (Priv))
11937 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
11939 -- Otherwise, search to the end of items currently linked to the full
11940 -- subtype and append the private items to the end. However, if Priv
11941 -- and Full already have the same list of rep items, then the append
11942 -- is not done, as that would create a circularity.
11944 elsif Item /= First_Rep_Item (Priv) then
11947 Next_Item := Next_Rep_Item (Item);
11948 exit when No (Next_Item);
11951 -- If the private view has aspect specifications, the full view
11952 -- inherits them. Since these aspects may already have been
11953 -- attached to the full view during derivation, do not append
11954 -- them if already present.
11956 if Item = First_Rep_Item (Priv) then
11962 -- And link the private type items at the end of the chain
11965 Set_Next_Rep_Item (Item, First_Rep_Item (Priv));
11970 -- Make sure Has_Predicates is set on full type if it is set on the
11971 -- private type. Note that it may already be set on the full type and
11972 -- if so, we don't want to unset it. Similarly, propagate information
11973 -- about delayed aspects, because the corresponding pragmas must be
11974 -- analyzed when one of the views is frozen. This last step is needed
11975 -- in particular when the full type is a scalar type for which an
11976 -- anonymous base type is constructed.
11978 if Has_Predicates (Priv) then
11979 Set_Has_Predicates (Full);
11982 if Has_Delayed_Aspects (Priv) then
11983 Set_Has_Delayed_Aspects (Full);
11985 end Complete_Private_Subtype;
11987 ----------------------------
11988 -- Constant_Redeclaration --
11989 ----------------------------
11991 procedure Constant_Redeclaration
11996 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
11997 Obj_Def : constant Node_Id := Object_Definition (N);
12000 procedure Check_Possible_Deferred_Completion
12001 (Prev_Id : Entity_Id;
12002 Prev_Obj_Def : Node_Id;
12003 Curr_Obj_Def : Node_Id);
12004 -- Determine whether the two object definitions describe the partial
12005 -- and the full view of a constrained deferred constant. Generate
12006 -- a subtype for the full view and verify that it statically matches
12007 -- the subtype of the partial view.
12009 procedure Check_Recursive_Declaration (Typ : Entity_Id);
12010 -- If deferred constant is an access type initialized with an allocator,
12011 -- check whether there is an illegal recursion in the definition,
12012 -- through a default value of some record subcomponent. This is normally
12013 -- detected when generating init procs, but requires this additional
12014 -- mechanism when expansion is disabled.
12016 ----------------------------------------
12017 -- Check_Possible_Deferred_Completion --
12018 ----------------------------------------
12020 procedure Check_Possible_Deferred_Completion
12021 (Prev_Id : Entity_Id;
12022 Prev_Obj_Def : Node_Id;
12023 Curr_Obj_Def : Node_Id)
12026 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
12027 and then Present (Constraint (Prev_Obj_Def))
12028 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
12029 and then Present (Constraint (Curr_Obj_Def))
12032 Loc : constant Source_Ptr := Sloc (N);
12033 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'S');
12034 Decl : constant Node_Id :=
12035 Make_Subtype_Declaration (Loc,
12036 Defining_Identifier => Def_Id,
12037 Subtype_Indication =>
12038 Relocate_Node (Curr_Obj_Def));
12041 Insert_Before_And_Analyze (N, Decl);
12042 Set_Etype (Id, Def_Id);
12044 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
12045 Error_Msg_Sloc := Sloc (Prev_Id);
12046 Error_Msg_N ("subtype does not statically match deferred "
12047 & "declaration #", N);
12051 end Check_Possible_Deferred_Completion;
12053 ---------------------------------
12054 -- Check_Recursive_Declaration --
12055 ---------------------------------
12057 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
12061 if Is_Record_Type (Typ) then
12062 Comp := First_Component (Typ);
12063 while Present (Comp) loop
12064 if Comes_From_Source (Comp) then
12065 if Present (Expression (Parent (Comp)))
12066 and then Is_Entity_Name (Expression (Parent (Comp)))
12067 and then Entity (Expression (Parent (Comp))) = Prev
12069 Error_Msg_Sloc := Sloc (Parent (Comp));
12071 ("illegal circularity with declaration for & #",
12075 elsif Is_Record_Type (Etype (Comp)) then
12076 Check_Recursive_Declaration (Etype (Comp));
12080 Next_Component (Comp);
12083 end Check_Recursive_Declaration;
12085 -- Start of processing for Constant_Redeclaration
12088 if Nkind (Parent (Prev)) = N_Object_Declaration then
12089 if Nkind (Object_Definition
12090 (Parent (Prev))) = N_Subtype_Indication
12092 -- Find type of new declaration. The constraints of the two
12093 -- views must match statically, but there is no point in
12094 -- creating an itype for the full view.
12096 if Nkind (Obj_Def) = N_Subtype_Indication then
12097 Find_Type (Subtype_Mark (Obj_Def));
12098 New_T := Entity (Subtype_Mark (Obj_Def));
12101 Find_Type (Obj_Def);
12102 New_T := Entity (Obj_Def);
12108 -- The full view may impose a constraint, even if the partial
12109 -- view does not, so construct the subtype.
12111 New_T := Find_Type_Of_Object (Obj_Def, N);
12116 -- Current declaration is illegal, diagnosed below in Enter_Name
12122 -- If previous full declaration or a renaming declaration exists, or if
12123 -- a homograph is present, let Enter_Name handle it, either with an
12124 -- error or with the removal of an overridden implicit subprogram.
12125 -- The previous one is a full declaration if it has an expression
12126 -- (which in the case of an aggregate is indicated by the Init flag).
12128 if Ekind (Prev) /= E_Constant
12129 or else Nkind (Parent (Prev)) = N_Object_Renaming_Declaration
12130 or else Present (Expression (Parent (Prev)))
12131 or else Has_Init_Expression (Parent (Prev))
12132 or else Present (Full_View (Prev))
12136 -- Verify that types of both declarations match, or else that both types
12137 -- are anonymous access types whose designated subtypes statically match
12138 -- (as allowed in Ada 2005 by AI-385).
12140 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
12142 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
12143 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
12144 or else Is_Access_Constant (Etype (New_T)) /=
12145 Is_Access_Constant (Etype (Prev))
12146 or else Can_Never_Be_Null (Etype (New_T)) /=
12147 Can_Never_Be_Null (Etype (Prev))
12148 or else Null_Exclusion_Present (Parent (Prev)) /=
12149 Null_Exclusion_Present (Parent (Id))
12150 or else not Subtypes_Statically_Match
12151 (Designated_Type (Etype (Prev)),
12152 Designated_Type (Etype (New_T))))
12154 Error_Msg_Sloc := Sloc (Prev);
12155 Error_Msg_N ("type does not match declaration#", N);
12156 Set_Full_View (Prev, Id);
12157 Set_Etype (Id, Any_Type);
12159 -- A deferred constant whose type is an anonymous array is always
12160 -- illegal (unless imported). A detailed error message might be
12161 -- helpful for Ada beginners.
12163 if Nkind (Object_Definition (Parent (Prev)))
12164 = N_Constrained_Array_Definition
12165 and then Nkind (Object_Definition (N))
12166 = N_Constrained_Array_Definition
12168 Error_Msg_N ("\each anonymous array is a distinct type", N);
12169 Error_Msg_N ("a deferred constant must have a named type",
12170 Object_Definition (Parent (Prev)));
12174 Null_Exclusion_Present (Parent (Prev))
12175 and then not Null_Exclusion_Present (N)
12177 Error_Msg_Sloc := Sloc (Prev);
12178 Error_Msg_N ("null-exclusion does not match declaration#", N);
12179 Set_Full_View (Prev, Id);
12180 Set_Etype (Id, Any_Type);
12182 -- If so, process the full constant declaration
12185 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
12186 -- the deferred declaration is constrained, then the subtype defined
12187 -- by the subtype_indication in the full declaration shall match it
12190 Check_Possible_Deferred_Completion
12192 Prev_Obj_Def => Object_Definition (Parent (Prev)),
12193 Curr_Obj_Def => Obj_Def);
12195 Set_Full_View (Prev, Id);
12196 Set_Is_Public (Id, Is_Public (Prev));
12197 Set_Is_Internal (Id);
12198 Append_Entity (Id, Current_Scope);
12200 -- Check ALIASED present if present before (RM 7.4(7))
12202 if Is_Aliased (Prev)
12203 and then not Aliased_Present (N)
12205 Error_Msg_Sloc := Sloc (Prev);
12206 Error_Msg_N ("ALIASED required (see declaration #)", N);
12209 -- Check that placement is in private part and that the incomplete
12210 -- declaration appeared in the visible part.
12212 if Ekind (Current_Scope) = E_Package
12213 and then not In_Private_Part (Current_Scope)
12215 Error_Msg_Sloc := Sloc (Prev);
12217 ("full constant for declaration # must be in private part", N);
12219 elsif Ekind (Current_Scope) = E_Package
12221 List_Containing (Parent (Prev)) /=
12222 Visible_Declarations (Package_Specification (Current_Scope))
12225 ("deferred constant must be declared in visible part",
12229 if Is_Access_Type (T)
12230 and then Nkind (Expression (N)) = N_Allocator
12232 Check_Recursive_Declaration (Designated_Type (T));
12235 -- A deferred constant is a visible entity. If type has invariants,
12236 -- verify that the initial value satisfies them.
12238 if Has_Invariants (T) and then Present (Invariant_Procedure (T)) then
12240 Make_Invariant_Call (New_Occurrence_Of (Prev, Sloc (N))));
12243 end Constant_Redeclaration;
12245 ----------------------
12246 -- Constrain_Access --
12247 ----------------------
12249 procedure Constrain_Access
12250 (Def_Id : in out Entity_Id;
12252 Related_Nod : Node_Id)
12254 T : constant Entity_Id := Entity (Subtype_Mark (S));
12255 Desig_Type : constant Entity_Id := Designated_Type (T);
12256 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
12257 Constraint_OK : Boolean := True;
12260 if Is_Array_Type (Desig_Type) then
12261 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
12263 elsif (Is_Record_Type (Desig_Type)
12264 or else Is_Incomplete_Or_Private_Type (Desig_Type))
12265 and then not Is_Constrained (Desig_Type)
12267 -- ??? The following code is a temporary bypass to ignore a
12268 -- discriminant constraint on access type if it is constraining
12269 -- the current record. Avoid creating the implicit subtype of the
12270 -- record we are currently compiling since right now, we cannot
12271 -- handle these. For now, just return the access type itself.
12273 if Desig_Type = Current_Scope
12274 and then No (Def_Id)
12276 Set_Ekind (Desig_Subtype, E_Record_Subtype);
12277 Def_Id := Entity (Subtype_Mark (S));
12279 -- This call added to ensure that the constraint is analyzed
12280 -- (needed for a B test). Note that we still return early from
12281 -- this procedure to avoid recursive processing. ???
12283 Constrain_Discriminated_Type
12284 (Desig_Subtype, S, Related_Nod, For_Access => True);
12288 -- Enforce rule that the constraint is illegal if there is an
12289 -- unconstrained view of the designated type. This means that the
12290 -- partial view (either a private type declaration or a derivation
12291 -- from a private type) has no discriminants. (Defect Report
12292 -- 8652/0008, Technical Corrigendum 1, checked by ACATS B371001).
12294 -- Rule updated for Ada 2005: The private type is said to have
12295 -- a constrained partial view, given that objects of the type
12296 -- can be declared. Furthermore, the rule applies to all access
12297 -- types, unlike the rule concerning default discriminants (see
12300 if (Ekind (T) = E_General_Access_Type or else Ada_Version >= Ada_2005)
12301 and then Has_Private_Declaration (Desig_Type)
12302 and then In_Open_Scopes (Scope (Desig_Type))
12303 and then Has_Discriminants (Desig_Type)
12306 Pack : constant Node_Id :=
12307 Unit_Declaration_Node (Scope (Desig_Type));
12312 if Nkind (Pack) = N_Package_Declaration then
12313 Decls := Visible_Declarations (Specification (Pack));
12314 Decl := First (Decls);
12315 while Present (Decl) loop
12316 if (Nkind (Decl) = N_Private_Type_Declaration
12317 and then Chars (Defining_Identifier (Decl)) =
12318 Chars (Desig_Type))
12321 (Nkind (Decl) = N_Full_Type_Declaration
12323 Chars (Defining_Identifier (Decl)) =
12325 and then Is_Derived_Type (Desig_Type)
12327 Has_Private_Declaration (Etype (Desig_Type)))
12329 if No (Discriminant_Specifications (Decl)) then
12331 ("cannot constrain access type if designated "
12332 & "type has constrained partial view", S);
12344 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
12345 For_Access => True);
12347 elsif Is_Concurrent_Type (Desig_Type)
12348 and then not Is_Constrained (Desig_Type)
12350 Constrain_Concurrent (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
12353 Error_Msg_N ("invalid constraint on access type", S);
12355 -- We simply ignore an invalid constraint
12357 Desig_Subtype := Desig_Type;
12358 Constraint_OK := False;
12361 if No (Def_Id) then
12362 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
12364 Set_Ekind (Def_Id, E_Access_Subtype);
12367 if Constraint_OK then
12368 Set_Etype (Def_Id, Base_Type (T));
12370 if Is_Private_Type (Desig_Type) then
12371 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
12374 Set_Etype (Def_Id, Any_Type);
12377 Set_Size_Info (Def_Id, T);
12378 Set_Is_Constrained (Def_Id, Constraint_OK);
12379 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
12380 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12381 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
12383 Conditional_Delay (Def_Id, T);
12385 -- AI-363 : Subtypes of general access types whose designated types have
12386 -- default discriminants are disallowed. In instances, the rule has to
12387 -- be checked against the actual, of which T is the subtype. In a
12388 -- generic body, the rule is checked assuming that the actual type has
12389 -- defaulted discriminants.
12391 if Ada_Version >= Ada_2005 or else Warn_On_Ada_2005_Compatibility then
12392 if Ekind (Base_Type (T)) = E_General_Access_Type
12393 and then Has_Defaulted_Discriminants (Desig_Type)
12395 if Ada_Version < Ada_2005 then
12397 ("access subtype of general access type would not " &
12398 "be allowed in Ada 2005?y?", S);
12401 ("access subtype of general access type not allowed", S);
12404 Error_Msg_N ("\discriminants have defaults", S);
12406 elsif Is_Access_Type (T)
12407 and then Is_Generic_Type (Desig_Type)
12408 and then Has_Discriminants (Desig_Type)
12409 and then In_Package_Body (Current_Scope)
12411 if Ada_Version < Ada_2005 then
12413 ("access subtype would not be allowed in generic body "
12414 & "in Ada 2005?y?", S);
12417 ("access subtype not allowed in generic body", S);
12421 ("\designated type is a discriminated formal", S);
12424 end Constrain_Access;
12426 ---------------------
12427 -- Constrain_Array --
12428 ---------------------
12430 procedure Constrain_Array
12431 (Def_Id : in out Entity_Id;
12433 Related_Nod : Node_Id;
12434 Related_Id : Entity_Id;
12435 Suffix : Character)
12437 C : constant Node_Id := Constraint (SI);
12438 Number_Of_Constraints : Nat := 0;
12441 Constraint_OK : Boolean := True;
12444 T := Entity (Subtype_Mark (SI));
12446 if Is_Access_Type (T) then
12447 T := Designated_Type (T);
12450 -- If an index constraint follows a subtype mark in a subtype indication
12451 -- then the type or subtype denoted by the subtype mark must not already
12452 -- impose an index constraint. The subtype mark must denote either an
12453 -- unconstrained array type or an access type whose designated type
12454 -- is such an array type... (RM 3.6.1)
12456 if Is_Constrained (T) then
12457 Error_Msg_N ("array type is already constrained", Subtype_Mark (SI));
12458 Constraint_OK := False;
12461 S := First (Constraints (C));
12462 while Present (S) loop
12463 Number_Of_Constraints := Number_Of_Constraints + 1;
12467 -- In either case, the index constraint must provide a discrete
12468 -- range for each index of the array type and the type of each
12469 -- discrete range must be the same as that of the corresponding
12470 -- index. (RM 3.6.1)
12472 if Number_Of_Constraints /= Number_Dimensions (T) then
12473 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
12474 Constraint_OK := False;
12477 S := First (Constraints (C));
12478 Index := First_Index (T);
12481 -- Apply constraints to each index type
12483 for J in 1 .. Number_Of_Constraints loop
12484 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
12492 if No (Def_Id) then
12494 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
12495 Set_Parent (Def_Id, Related_Nod);
12498 Set_Ekind (Def_Id, E_Array_Subtype);
12501 Set_Size_Info (Def_Id, (T));
12502 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12503 Set_Etype (Def_Id, Base_Type (T));
12505 if Constraint_OK then
12506 Set_First_Index (Def_Id, First (Constraints (C)));
12508 Set_First_Index (Def_Id, First_Index (T));
12511 Set_Is_Constrained (Def_Id, True);
12512 Set_Is_Aliased (Def_Id, Is_Aliased (T));
12513 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12515 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
12516 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
12518 -- A subtype does not inherit the Packed_Array_Impl_Type of is parent.
12519 -- We need to initialize the attribute because if Def_Id is previously
12520 -- analyzed through a limited_with clause, it will have the attributes
12521 -- of an incomplete type, one of which is an Elist that overlaps the
12522 -- Packed_Array_Impl_Type field.
12524 Set_Packed_Array_Impl_Type (Def_Id, Empty);
12526 -- Build a freeze node if parent still needs one. Also make sure that
12527 -- the Depends_On_Private status is set because the subtype will need
12528 -- reprocessing at the time the base type does, and also we must set a
12529 -- conditional delay.
12531 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
12532 Conditional_Delay (Def_Id, T);
12533 end Constrain_Array;
12535 ------------------------------
12536 -- Constrain_Component_Type --
12537 ------------------------------
12539 function Constrain_Component_Type
12541 Constrained_Typ : Entity_Id;
12542 Related_Node : Node_Id;
12544 Constraints : Elist_Id) return Entity_Id
12546 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
12547 Compon_Type : constant Entity_Id := Etype (Comp);
12549 function Build_Constrained_Array_Type
12550 (Old_Type : Entity_Id) return Entity_Id;
12551 -- If Old_Type is an array type, one of whose indexes is constrained
12552 -- by a discriminant, build an Itype whose constraint replaces the
12553 -- discriminant with its value in the constraint.
12555 function Build_Constrained_Discriminated_Type
12556 (Old_Type : Entity_Id) return Entity_Id;
12557 -- Ditto for record components
12559 function Build_Constrained_Access_Type
12560 (Old_Type : Entity_Id) return Entity_Id;
12561 -- Ditto for access types. Makes use of previous two functions, to
12562 -- constrain designated type.
12564 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
12565 -- T is an array or discriminated type, C is a list of constraints
12566 -- that apply to T. This routine builds the constrained subtype.
12568 function Is_Discriminant (Expr : Node_Id) return Boolean;
12569 -- Returns True if Expr is a discriminant
12571 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
12572 -- Find the value of discriminant Discrim in Constraint
12574 -----------------------------------
12575 -- Build_Constrained_Access_Type --
12576 -----------------------------------
12578 function Build_Constrained_Access_Type
12579 (Old_Type : Entity_Id) return Entity_Id
12581 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
12583 Desig_Subtype : Entity_Id;
12587 -- if the original access type was not embedded in the enclosing
12588 -- type definition, there is no need to produce a new access
12589 -- subtype. In fact every access type with an explicit constraint
12590 -- generates an itype whose scope is the enclosing record.
12592 if not Is_Type (Scope (Old_Type)) then
12595 elsif Is_Array_Type (Desig_Type) then
12596 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
12598 elsif Has_Discriminants (Desig_Type) then
12600 -- This may be an access type to an enclosing record type for
12601 -- which we are constructing the constrained components. Return
12602 -- the enclosing record subtype. This is not always correct,
12603 -- but avoids infinite recursion. ???
12605 Desig_Subtype := Any_Type;
12607 for J in reverse 0 .. Scope_Stack.Last loop
12608 Scop := Scope_Stack.Table (J).Entity;
12611 and then Base_Type (Scop) = Base_Type (Desig_Type)
12613 Desig_Subtype := Scop;
12616 exit when not Is_Type (Scop);
12619 if Desig_Subtype = Any_Type then
12621 Build_Constrained_Discriminated_Type (Desig_Type);
12628 if Desig_Subtype /= Desig_Type then
12630 -- The Related_Node better be here or else we won't be able
12631 -- to attach new itypes to a node in the tree.
12633 pragma Assert (Present (Related_Node));
12635 Itype := Create_Itype (E_Access_Subtype, Related_Node);
12637 Set_Etype (Itype, Base_Type (Old_Type));
12638 Set_Size_Info (Itype, (Old_Type));
12639 Set_Directly_Designated_Type (Itype, Desig_Subtype);
12640 Set_Depends_On_Private (Itype, Has_Private_Component
12642 Set_Is_Access_Constant (Itype, Is_Access_Constant
12645 -- The new itype needs freezing when it depends on a not frozen
12646 -- type and the enclosing subtype needs freezing.
12648 if Has_Delayed_Freeze (Constrained_Typ)
12649 and then not Is_Frozen (Constrained_Typ)
12651 Conditional_Delay (Itype, Base_Type (Old_Type));
12659 end Build_Constrained_Access_Type;
12661 ----------------------------------
12662 -- Build_Constrained_Array_Type --
12663 ----------------------------------
12665 function Build_Constrained_Array_Type
12666 (Old_Type : Entity_Id) return Entity_Id
12670 Old_Index : Node_Id;
12671 Range_Node : Node_Id;
12672 Constr_List : List_Id;
12674 Need_To_Create_Itype : Boolean := False;
12677 Old_Index := First_Index (Old_Type);
12678 while Present (Old_Index) loop
12679 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
12681 if Is_Discriminant (Lo_Expr)
12683 Is_Discriminant (Hi_Expr)
12685 Need_To_Create_Itype := True;
12688 Next_Index (Old_Index);
12691 if Need_To_Create_Itype then
12692 Constr_List := New_List;
12694 Old_Index := First_Index (Old_Type);
12695 while Present (Old_Index) loop
12696 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
12698 if Is_Discriminant (Lo_Expr) then
12699 Lo_Expr := Get_Discr_Value (Lo_Expr);
12702 if Is_Discriminant (Hi_Expr) then
12703 Hi_Expr := Get_Discr_Value (Hi_Expr);
12708 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
12710 Append (Range_Node, To => Constr_List);
12712 Next_Index (Old_Index);
12715 return Build_Subtype (Old_Type, Constr_List);
12720 end Build_Constrained_Array_Type;
12722 ------------------------------------------
12723 -- Build_Constrained_Discriminated_Type --
12724 ------------------------------------------
12726 function Build_Constrained_Discriminated_Type
12727 (Old_Type : Entity_Id) return Entity_Id
12730 Constr_List : List_Id;
12731 Old_Constraint : Elmt_Id;
12733 Need_To_Create_Itype : Boolean := False;
12736 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
12737 while Present (Old_Constraint) loop
12738 Expr := Node (Old_Constraint);
12740 if Is_Discriminant (Expr) then
12741 Need_To_Create_Itype := True;
12744 Next_Elmt (Old_Constraint);
12747 if Need_To_Create_Itype then
12748 Constr_List := New_List;
12750 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
12751 while Present (Old_Constraint) loop
12752 Expr := Node (Old_Constraint);
12754 if Is_Discriminant (Expr) then
12755 Expr := Get_Discr_Value (Expr);
12758 Append (New_Copy_Tree (Expr), To => Constr_List);
12760 Next_Elmt (Old_Constraint);
12763 return Build_Subtype (Old_Type, Constr_List);
12768 end Build_Constrained_Discriminated_Type;
12770 -------------------
12771 -- Build_Subtype --
12772 -------------------
12774 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
12776 Subtyp_Decl : Node_Id;
12777 Def_Id : Entity_Id;
12778 Btyp : Entity_Id := Base_Type (T);
12781 -- The Related_Node better be here or else we won't be able to
12782 -- attach new itypes to a node in the tree.
12784 pragma Assert (Present (Related_Node));
12786 -- If the view of the component's type is incomplete or private
12787 -- with unknown discriminants, then the constraint must be applied
12788 -- to the full type.
12790 if Has_Unknown_Discriminants (Btyp)
12791 and then Present (Underlying_Type (Btyp))
12793 Btyp := Underlying_Type (Btyp);
12797 Make_Subtype_Indication (Loc,
12798 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
12799 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
12801 Def_Id := Create_Itype (Ekind (T), Related_Node);
12804 Make_Subtype_Declaration (Loc,
12805 Defining_Identifier => Def_Id,
12806 Subtype_Indication => Indic);
12808 Set_Parent (Subtyp_Decl, Parent (Related_Node));
12810 -- Itypes must be analyzed with checks off (see package Itypes)
12812 Analyze (Subtyp_Decl, Suppress => All_Checks);
12817 ---------------------
12818 -- Get_Discr_Value --
12819 ---------------------
12821 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
12826 -- The discriminant may be declared for the type, in which case we
12827 -- find it by iterating over the list of discriminants. If the
12828 -- discriminant is inherited from a parent type, it appears as the
12829 -- corresponding discriminant of the current type. This will be the
12830 -- case when constraining an inherited component whose constraint is
12831 -- given by a discriminant of the parent.
12833 D := First_Discriminant (Typ);
12834 E := First_Elmt (Constraints);
12836 while Present (D) loop
12837 if D = Entity (Discrim)
12838 or else D = CR_Discriminant (Entity (Discrim))
12839 or else Corresponding_Discriminant (D) = Entity (Discrim)
12844 Next_Discriminant (D);
12848 -- The Corresponding_Discriminant mechanism is incomplete, because
12849 -- the correspondence between new and old discriminants is not one
12850 -- to one: one new discriminant can constrain several old ones. In
12851 -- that case, scan sequentially the stored_constraint, the list of
12852 -- discriminants of the parents, and the constraints.
12854 -- Previous code checked for the present of the Stored_Constraint
12855 -- list for the derived type, but did not use it at all. Should it
12856 -- be present when the component is a discriminated task type?
12858 if Is_Derived_Type (Typ)
12859 and then Scope (Entity (Discrim)) = Etype (Typ)
12861 D := First_Discriminant (Etype (Typ));
12862 E := First_Elmt (Constraints);
12863 while Present (D) loop
12864 if D = Entity (Discrim) then
12868 Next_Discriminant (D);
12873 -- Something is wrong if we did not find the value
12875 raise Program_Error;
12876 end Get_Discr_Value;
12878 ---------------------
12879 -- Is_Discriminant --
12880 ---------------------
12882 function Is_Discriminant (Expr : Node_Id) return Boolean is
12883 Discrim_Scope : Entity_Id;
12886 if Denotes_Discriminant (Expr) then
12887 Discrim_Scope := Scope (Entity (Expr));
12889 -- Either we have a reference to one of Typ's discriminants,
12891 pragma Assert (Discrim_Scope = Typ
12893 -- or to the discriminants of the parent type, in the case
12894 -- of a derivation of a tagged type with variants.
12896 or else Discrim_Scope = Etype (Typ)
12897 or else Full_View (Discrim_Scope) = Etype (Typ)
12899 -- or same as above for the case where the discriminants
12900 -- were declared in Typ's private view.
12902 or else (Is_Private_Type (Discrim_Scope)
12903 and then Chars (Discrim_Scope) = Chars (Typ))
12905 -- or else we are deriving from the full view and the
12906 -- discriminant is declared in the private entity.
12908 or else (Is_Private_Type (Typ)
12909 and then Chars (Discrim_Scope) = Chars (Typ))
12911 -- Or we are constrained the corresponding record of a
12912 -- synchronized type that completes a private declaration.
12914 or else (Is_Concurrent_Record_Type (Typ)
12916 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
12918 -- or we have a class-wide type, in which case make sure the
12919 -- discriminant found belongs to the root type.
12921 or else (Is_Class_Wide_Type (Typ)
12922 and then Etype (Typ) = Discrim_Scope));
12927 -- In all other cases we have something wrong
12930 end Is_Discriminant;
12932 -- Start of processing for Constrain_Component_Type
12935 if Nkind (Parent (Comp)) = N_Component_Declaration
12936 and then Comes_From_Source (Parent (Comp))
12937 and then Comes_From_Source
12938 (Subtype_Indication (Component_Definition (Parent (Comp))))
12941 (Subtype_Indication (Component_Definition (Parent (Comp))))
12943 return Compon_Type;
12945 elsif Is_Array_Type (Compon_Type) then
12946 return Build_Constrained_Array_Type (Compon_Type);
12948 elsif Has_Discriminants (Compon_Type) then
12949 return Build_Constrained_Discriminated_Type (Compon_Type);
12951 elsif Is_Access_Type (Compon_Type) then
12952 return Build_Constrained_Access_Type (Compon_Type);
12955 return Compon_Type;
12957 end Constrain_Component_Type;
12959 --------------------------
12960 -- Constrain_Concurrent --
12961 --------------------------
12963 -- For concurrent types, the associated record value type carries the same
12964 -- discriminants, so when we constrain a concurrent type, we must constrain
12965 -- the corresponding record type as well.
12967 procedure Constrain_Concurrent
12968 (Def_Id : in out Entity_Id;
12970 Related_Nod : Node_Id;
12971 Related_Id : Entity_Id;
12972 Suffix : Character)
12974 -- Retrieve Base_Type to ensure getting to the concurrent type in the
12975 -- case of a private subtype (needed when only doing semantic analysis).
12977 T_Ent : Entity_Id := Base_Type (Entity (Subtype_Mark (SI)));
12981 if Is_Access_Type (T_Ent) then
12982 T_Ent := Designated_Type (T_Ent);
12985 T_Val := Corresponding_Record_Type (T_Ent);
12987 if Present (T_Val) then
12989 if No (Def_Id) then
12990 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
12992 -- Elaborate itype now, as it may be used in a subsequent
12993 -- synchronized operation in another scope.
12995 if Nkind (Related_Nod) = N_Full_Type_Declaration then
12996 Build_Itype_Reference (Def_Id, Related_Nod);
13000 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
13002 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
13003 Set_Corresponding_Record_Type (Def_Id,
13004 Constrain_Corresponding_Record (Def_Id, T_Val, Related_Nod));
13007 -- If there is no associated record, expansion is disabled and this
13008 -- is a generic context. Create a subtype in any case, so that
13009 -- semantic analysis can proceed.
13011 if No (Def_Id) then
13012 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
13015 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
13017 end Constrain_Concurrent;
13019 ------------------------------------
13020 -- Constrain_Corresponding_Record --
13021 ------------------------------------
13023 function Constrain_Corresponding_Record
13024 (Prot_Subt : Entity_Id;
13025 Corr_Rec : Entity_Id;
13026 Related_Nod : Node_Id) return Entity_Id
13028 T_Sub : constant Entity_Id :=
13029 Create_Itype (E_Record_Subtype, Related_Nod, Corr_Rec, 'C');
13032 Set_Etype (T_Sub, Corr_Rec);
13033 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
13034 Set_Is_Constrained (T_Sub, True);
13035 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
13036 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
13038 if Has_Discriminants (Prot_Subt) then -- False only if errors.
13039 Set_Discriminant_Constraint
13040 (T_Sub, Discriminant_Constraint (Prot_Subt));
13041 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
13042 Create_Constrained_Components
13043 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
13046 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
13048 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
13049 Conditional_Delay (T_Sub, Corr_Rec);
13052 -- This is a component subtype: it will be frozen in the context of
13053 -- the enclosing record's init_proc, so that discriminant references
13054 -- are resolved to discriminals. (Note: we used to skip freezing
13055 -- altogether in that case, which caused errors downstream for
13056 -- components of a bit packed array type).
13058 Set_Has_Delayed_Freeze (T_Sub);
13062 end Constrain_Corresponding_Record;
13064 -----------------------
13065 -- Constrain_Decimal --
13066 -----------------------
13068 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
13069 T : constant Entity_Id := Entity (Subtype_Mark (S));
13070 C : constant Node_Id := Constraint (S);
13071 Loc : constant Source_Ptr := Sloc (C);
13072 Range_Expr : Node_Id;
13073 Digits_Expr : Node_Id;
13078 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
13080 if Nkind (C) = N_Range_Constraint then
13081 Range_Expr := Range_Expression (C);
13082 Digits_Val := Digits_Value (T);
13085 pragma Assert (Nkind (C) = N_Digits_Constraint);
13087 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
13089 Digits_Expr := Digits_Expression (C);
13090 Analyze_And_Resolve (Digits_Expr, Any_Integer);
13092 Check_Digits_Expression (Digits_Expr);
13093 Digits_Val := Expr_Value (Digits_Expr);
13095 if Digits_Val > Digits_Value (T) then
13097 ("digits expression is incompatible with subtype", C);
13098 Digits_Val := Digits_Value (T);
13101 if Present (Range_Constraint (C)) then
13102 Range_Expr := Range_Expression (Range_Constraint (C));
13104 Range_Expr := Empty;
13108 Set_Etype (Def_Id, Base_Type (T));
13109 Set_Size_Info (Def_Id, (T));
13110 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13111 Set_Delta_Value (Def_Id, Delta_Value (T));
13112 Set_Scale_Value (Def_Id, Scale_Value (T));
13113 Set_Small_Value (Def_Id, Small_Value (T));
13114 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
13115 Set_Digits_Value (Def_Id, Digits_Val);
13117 -- Manufacture range from given digits value if no range present
13119 if No (Range_Expr) then
13120 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
13124 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
13126 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
13129 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
13130 Set_Discrete_RM_Size (Def_Id);
13132 -- Unconditionally delay the freeze, since we cannot set size
13133 -- information in all cases correctly until the freeze point.
13135 Set_Has_Delayed_Freeze (Def_Id);
13136 end Constrain_Decimal;
13138 ----------------------------------
13139 -- Constrain_Discriminated_Type --
13140 ----------------------------------
13142 procedure Constrain_Discriminated_Type
13143 (Def_Id : Entity_Id;
13145 Related_Nod : Node_Id;
13146 For_Access : Boolean := False)
13148 E : constant Entity_Id := Entity (Subtype_Mark (S));
13151 Elist : Elist_Id := New_Elmt_List;
13153 procedure Fixup_Bad_Constraint;
13154 -- This is called after finding a bad constraint, and after having
13155 -- posted an appropriate error message. The mission is to leave the
13156 -- entity T in as reasonable state as possible.
13158 --------------------------
13159 -- Fixup_Bad_Constraint --
13160 --------------------------
13162 procedure Fixup_Bad_Constraint is
13164 -- Set a reasonable Ekind for the entity. For an incomplete type,
13165 -- we can't do much, but for other types, we can set the proper
13166 -- corresponding subtype kind.
13168 if Ekind (T) = E_Incomplete_Type then
13169 Set_Ekind (Def_Id, Ekind (T));
13171 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
13174 -- Set Etype to the known type, to reduce chances of cascaded errors
13176 Set_Etype (Def_Id, E);
13177 Set_Error_Posted (Def_Id);
13178 end Fixup_Bad_Constraint;
13180 -- Start of processing for Constrain_Discriminated_Type
13183 C := Constraint (S);
13185 -- A discriminant constraint is only allowed in a subtype indication,
13186 -- after a subtype mark. This subtype mark must denote either a type
13187 -- with discriminants, or an access type whose designated type is a
13188 -- type with discriminants. A discriminant constraint specifies the
13189 -- values of these discriminants (RM 3.7.2(5)).
13191 T := Base_Type (Entity (Subtype_Mark (S)));
13193 if Is_Access_Type (T) then
13194 T := Designated_Type (T);
13197 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal.
13198 -- Avoid generating an error for access-to-incomplete subtypes.
13200 if Ada_Version >= Ada_2005
13201 and then Ekind (T) = E_Incomplete_Type
13202 and then Nkind (Parent (S)) = N_Subtype_Declaration
13203 and then not Is_Itype (Def_Id)
13205 -- A little sanity check, emit an error message if the type
13206 -- has discriminants to begin with. Type T may be a regular
13207 -- incomplete type or imported via a limited with clause.
13209 if Has_Discriminants (T)
13210 or else (From_Limited_With (T)
13211 and then Present (Non_Limited_View (T))
13212 and then Nkind (Parent (Non_Limited_View (T))) =
13213 N_Full_Type_Declaration
13214 and then Present (Discriminant_Specifications
13215 (Parent (Non_Limited_View (T)))))
13218 ("(Ada 2005) incomplete subtype may not be constrained", C);
13220 Error_Msg_N ("invalid constraint: type has no discriminant", C);
13223 Fixup_Bad_Constraint;
13226 -- Check that the type has visible discriminants. The type may be
13227 -- a private type with unknown discriminants whose full view has
13228 -- discriminants which are invisible.
13230 elsif not Has_Discriminants (T)
13232 (Has_Unknown_Discriminants (T)
13233 and then Is_Private_Type (T))
13235 Error_Msg_N ("invalid constraint: type has no discriminant", C);
13236 Fixup_Bad_Constraint;
13239 elsif Is_Constrained (E)
13240 or else (Ekind (E) = E_Class_Wide_Subtype
13241 and then Present (Discriminant_Constraint (E)))
13243 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
13244 Fixup_Bad_Constraint;
13248 -- T may be an unconstrained subtype (e.g. a generic actual).
13249 -- Constraint applies to the base type.
13251 T := Base_Type (T);
13253 Elist := Build_Discriminant_Constraints (T, S);
13255 -- If the list returned was empty we had an error in building the
13256 -- discriminant constraint. We have also already signalled an error
13257 -- in the incomplete type case
13259 if Is_Empty_Elmt_List (Elist) then
13260 Fixup_Bad_Constraint;
13264 Build_Discriminated_Subtype (T, Def_Id, Elist, Related_Nod, For_Access);
13265 end Constrain_Discriminated_Type;
13267 ---------------------------
13268 -- Constrain_Enumeration --
13269 ---------------------------
13271 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
13272 T : constant Entity_Id := Entity (Subtype_Mark (S));
13273 C : constant Node_Id := Constraint (S);
13276 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13278 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
13280 Set_Etype (Def_Id, Base_Type (T));
13281 Set_Size_Info (Def_Id, (T));
13282 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13283 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13285 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13287 Set_Discrete_RM_Size (Def_Id);
13288 end Constrain_Enumeration;
13290 ----------------------
13291 -- Constrain_Float --
13292 ----------------------
13294 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
13295 T : constant Entity_Id := Entity (Subtype_Mark (S));
13301 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
13303 Set_Etype (Def_Id, Base_Type (T));
13304 Set_Size_Info (Def_Id, (T));
13305 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13307 -- Process the constraint
13309 C := Constraint (S);
13311 -- Digits constraint present
13313 if Nkind (C) = N_Digits_Constraint then
13315 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
13316 Check_Restriction (No_Obsolescent_Features, C);
13318 if Warn_On_Obsolescent_Feature then
13320 ("subtype digits constraint is an " &
13321 "obsolescent feature (RM J.3(8))?j?", C);
13324 D := Digits_Expression (C);
13325 Analyze_And_Resolve (D, Any_Integer);
13326 Check_Digits_Expression (D);
13327 Set_Digits_Value (Def_Id, Expr_Value (D));
13329 -- Check that digits value is in range. Obviously we can do this
13330 -- at compile time, but it is strictly a runtime check, and of
13331 -- course there is an ACVC test that checks this.
13333 if Digits_Value (Def_Id) > Digits_Value (T) then
13334 Error_Msg_Uint_1 := Digits_Value (T);
13335 Error_Msg_N ("??digits value is too large, maximum is ^", D);
13337 Make_Raise_Constraint_Error (Sloc (D),
13338 Reason => CE_Range_Check_Failed);
13339 Insert_Action (Declaration_Node (Def_Id), Rais);
13342 C := Range_Constraint (C);
13344 -- No digits constraint present
13347 Set_Digits_Value (Def_Id, Digits_Value (T));
13350 -- Range constraint present
13352 if Nkind (C) = N_Range_Constraint then
13353 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13355 -- No range constraint present
13358 pragma Assert (No (C));
13359 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13362 Set_Is_Constrained (Def_Id);
13363 end Constrain_Float;
13365 ---------------------
13366 -- Constrain_Index --
13367 ---------------------
13369 procedure Constrain_Index
13372 Related_Nod : Node_Id;
13373 Related_Id : Entity_Id;
13374 Suffix : Character;
13375 Suffix_Index : Nat)
13377 Def_Id : Entity_Id;
13378 R : Node_Id := Empty;
13379 T : constant Entity_Id := Etype (Index);
13383 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
13384 Set_Etype (Def_Id, Base_Type (T));
13386 if Nkind (S) = N_Range
13388 (Nkind (S) = N_Attribute_Reference
13389 and then Attribute_Name (S) = Name_Range)
13391 -- A Range attribute will be transformed into N_Range by Resolve
13397 Process_Range_Expr_In_Decl (R, T);
13399 if not Error_Posted (S)
13401 (Nkind (S) /= N_Range
13402 or else not Covers (T, (Etype (Low_Bound (S))))
13403 or else not Covers (T, (Etype (High_Bound (S)))))
13405 if Base_Type (T) /= Any_Type
13406 and then Etype (Low_Bound (S)) /= Any_Type
13407 and then Etype (High_Bound (S)) /= Any_Type
13409 Error_Msg_N ("range expected", S);
13413 elsif Nkind (S) = N_Subtype_Indication then
13415 -- The parser has verified that this is a discrete indication
13417 Resolve_Discrete_Subtype_Indication (S, T);
13418 Bad_Predicated_Subtype_Use
13419 ("subtype& has predicate, not allowed in index constraint",
13420 S, Entity (Subtype_Mark (S)));
13422 R := Range_Expression (Constraint (S));
13424 -- Capture values of bounds and generate temporaries for them if
13425 -- needed, since checks may cause duplication of the expressions
13426 -- which must not be reevaluated.
13428 -- The forced evaluation removes side effects from expressions, which
13429 -- should occur also in GNATprove mode. Otherwise, we end up with
13430 -- unexpected insertions of actions at places where this is not
13431 -- supposed to occur, e.g. on default parameters of a call.
13433 if Expander_Active or GNATprove_Mode then
13435 (Low_Bound (R), Related_Id => Def_Id, Is_Low_Bound => True);
13437 (High_Bound (R), Related_Id => Def_Id, Is_High_Bound => True);
13440 elsif Nkind (S) = N_Discriminant_Association then
13442 -- Syntactically valid in subtype indication
13444 Error_Msg_N ("invalid index constraint", S);
13445 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13448 -- Subtype_Mark case, no anonymous subtypes to construct
13453 if Is_Entity_Name (S) then
13454 if not Is_Type (Entity (S)) then
13455 Error_Msg_N ("expect subtype mark for index constraint", S);
13457 elsif Base_Type (Entity (S)) /= Base_Type (T) then
13458 Wrong_Type (S, Base_Type (T));
13460 -- Check error of subtype with predicate in index constraint
13463 Bad_Predicated_Subtype_Use
13464 ("subtype& has predicate, not allowed in index constraint",
13471 Error_Msg_N ("invalid index constraint", S);
13472 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13477 -- Complete construction of the Itype
13479 if Is_Modular_Integer_Type (T) then
13480 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13482 elsif Is_Integer_Type (T) then
13483 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13486 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13487 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13488 Set_First_Literal (Def_Id, First_Literal (T));
13491 Set_Size_Info (Def_Id, (T));
13492 Set_RM_Size (Def_Id, RM_Size (T));
13493 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13495 Set_Scalar_Range (Def_Id, R);
13497 Set_Etype (S, Def_Id);
13498 Set_Discrete_RM_Size (Def_Id);
13499 end Constrain_Index;
13501 -----------------------
13502 -- Constrain_Integer --
13503 -----------------------
13505 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
13506 T : constant Entity_Id := Entity (Subtype_Mark (S));
13507 C : constant Node_Id := Constraint (S);
13510 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13512 if Is_Modular_Integer_Type (T) then
13513 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13515 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13518 Set_Etype (Def_Id, Base_Type (T));
13519 Set_Size_Info (Def_Id, (T));
13520 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13521 Set_Discrete_RM_Size (Def_Id);
13522 end Constrain_Integer;
13524 ------------------------------
13525 -- Constrain_Ordinary_Fixed --
13526 ------------------------------
13528 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
13529 T : constant Entity_Id := Entity (Subtype_Mark (S));
13535 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
13536 Set_Etype (Def_Id, Base_Type (T));
13537 Set_Size_Info (Def_Id, (T));
13538 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13539 Set_Small_Value (Def_Id, Small_Value (T));
13541 -- Process the constraint
13543 C := Constraint (S);
13545 -- Delta constraint present
13547 if Nkind (C) = N_Delta_Constraint then
13549 Check_SPARK_05_Restriction ("delta constraint is not allowed", S);
13550 Check_Restriction (No_Obsolescent_Features, C);
13552 if Warn_On_Obsolescent_Feature then
13554 ("subtype delta constraint is an " &
13555 "obsolescent feature (RM J.3(7))?j?");
13558 D := Delta_Expression (C);
13559 Analyze_And_Resolve (D, Any_Real);
13560 Check_Delta_Expression (D);
13561 Set_Delta_Value (Def_Id, Expr_Value_R (D));
13563 -- Check that delta value is in range. Obviously we can do this
13564 -- at compile time, but it is strictly a runtime check, and of
13565 -- course there is an ACVC test that checks this.
13567 if Delta_Value (Def_Id) < Delta_Value (T) then
13568 Error_Msg_N ("??delta value is too small", D);
13570 Make_Raise_Constraint_Error (Sloc (D),
13571 Reason => CE_Range_Check_Failed);
13572 Insert_Action (Declaration_Node (Def_Id), Rais);
13575 C := Range_Constraint (C);
13577 -- No delta constraint present
13580 Set_Delta_Value (Def_Id, Delta_Value (T));
13583 -- Range constraint present
13585 if Nkind (C) = N_Range_Constraint then
13586 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13588 -- No range constraint present
13591 pragma Assert (No (C));
13592 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13595 Set_Discrete_RM_Size (Def_Id);
13597 -- Unconditionally delay the freeze, since we cannot set size
13598 -- information in all cases correctly until the freeze point.
13600 Set_Has_Delayed_Freeze (Def_Id);
13601 end Constrain_Ordinary_Fixed;
13603 -----------------------
13604 -- Contain_Interface --
13605 -----------------------
13607 function Contain_Interface
13608 (Iface : Entity_Id;
13609 Ifaces : Elist_Id) return Boolean
13611 Iface_Elmt : Elmt_Id;
13614 if Present (Ifaces) then
13615 Iface_Elmt := First_Elmt (Ifaces);
13616 while Present (Iface_Elmt) loop
13617 if Node (Iface_Elmt) = Iface then
13621 Next_Elmt (Iface_Elmt);
13626 end Contain_Interface;
13628 ---------------------------
13629 -- Convert_Scalar_Bounds --
13630 ---------------------------
13632 procedure Convert_Scalar_Bounds
13634 Parent_Type : Entity_Id;
13635 Derived_Type : Entity_Id;
13638 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
13645 -- Defend against previous errors
13647 if No (Scalar_Range (Derived_Type)) then
13648 Check_Error_Detected;
13652 Lo := Build_Scalar_Bound
13653 (Type_Low_Bound (Derived_Type),
13654 Parent_Type, Implicit_Base);
13656 Hi := Build_Scalar_Bound
13657 (Type_High_Bound (Derived_Type),
13658 Parent_Type, Implicit_Base);
13665 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
13667 Set_Parent (Rng, N);
13668 Set_Scalar_Range (Derived_Type, Rng);
13670 -- Analyze the bounds
13672 Analyze_And_Resolve (Lo, Implicit_Base);
13673 Analyze_And_Resolve (Hi, Implicit_Base);
13675 -- Analyze the range itself, except that we do not analyze it if
13676 -- the bounds are real literals, and we have a fixed-point type.
13677 -- The reason for this is that we delay setting the bounds in this
13678 -- case till we know the final Small and Size values (see circuit
13679 -- in Freeze.Freeze_Fixed_Point_Type for further details).
13681 if Is_Fixed_Point_Type (Parent_Type)
13682 and then Nkind (Lo) = N_Real_Literal
13683 and then Nkind (Hi) = N_Real_Literal
13687 -- Here we do the analysis of the range
13689 -- Note: we do this manually, since if we do a normal Analyze and
13690 -- Resolve call, there are problems with the conversions used for
13691 -- the derived type range.
13694 Set_Etype (Rng, Implicit_Base);
13695 Set_Analyzed (Rng, True);
13697 end Convert_Scalar_Bounds;
13699 -------------------
13700 -- Copy_And_Swap --
13701 -------------------
13703 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
13705 -- Initialize new full declaration entity by copying the pertinent
13706 -- fields of the corresponding private declaration entity.
13708 -- We temporarily set Ekind to a value appropriate for a type to
13709 -- avoid assert failures in Einfo from checking for setting type
13710 -- attributes on something that is not a type. Ekind (Priv) is an
13711 -- appropriate choice, since it allowed the attributes to be set
13712 -- in the first place. This Ekind value will be modified later.
13714 Set_Ekind (Full, Ekind (Priv));
13716 -- Also set Etype temporarily to Any_Type, again, in the absence
13717 -- of errors, it will be properly reset, and if there are errors,
13718 -- then we want a value of Any_Type to remain.
13720 Set_Etype (Full, Any_Type);
13722 -- Now start copying attributes
13724 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
13726 if Has_Discriminants (Full) then
13727 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
13728 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
13731 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
13732 Set_Homonym (Full, Homonym (Priv));
13733 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
13734 Set_Is_Public (Full, Is_Public (Priv));
13735 Set_Is_Pure (Full, Is_Pure (Priv));
13736 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
13737 Set_Has_Pragma_Unmodified (Full, Has_Pragma_Unmodified (Priv));
13738 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
13739 Set_Has_Pragma_Unreferenced_Objects
13740 (Full, Has_Pragma_Unreferenced_Objects
13743 Conditional_Delay (Full, Priv);
13745 if Is_Tagged_Type (Full) then
13746 Set_Direct_Primitive_Operations
13747 (Full, Direct_Primitive_Operations (Priv));
13748 Set_No_Tagged_Streams_Pragma
13749 (Full, No_Tagged_Streams_Pragma (Priv));
13751 if Is_Base_Type (Priv) then
13752 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
13756 Set_Is_Volatile (Full, Is_Volatile (Priv));
13757 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
13758 Set_Scope (Full, Scope (Priv));
13759 Set_Next_Entity (Full, Next_Entity (Priv));
13760 Set_First_Entity (Full, First_Entity (Priv));
13761 Set_Last_Entity (Full, Last_Entity (Priv));
13763 -- If access types have been recorded for later handling, keep them in
13764 -- the full view so that they get handled when the full view freeze
13765 -- node is expanded.
13767 if Present (Freeze_Node (Priv))
13768 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
13770 Ensure_Freeze_Node (Full);
13771 Set_Access_Types_To_Process
13772 (Freeze_Node (Full),
13773 Access_Types_To_Process (Freeze_Node (Priv)));
13776 -- Swap the two entities. Now Private is the full type entity and Full
13777 -- is the private one. They will be swapped back at the end of the
13778 -- private part. This swapping ensures that the entity that is visible
13779 -- in the private part is the full declaration.
13781 Exchange_Entities (Priv, Full);
13782 Append_Entity (Full, Scope (Full));
13785 -------------------------------------
13786 -- Copy_Array_Base_Type_Attributes --
13787 -------------------------------------
13789 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
13791 Set_Component_Alignment (T1, Component_Alignment (T2));
13792 Set_Component_Type (T1, Component_Type (T2));
13793 Set_Component_Size (T1, Component_Size (T2));
13794 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
13795 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
13796 Set_Has_Protected (T1, Has_Protected (T2));
13797 Set_Has_Task (T1, Has_Task (T2));
13798 Set_Is_Packed (T1, Is_Packed (T2));
13799 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
13800 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
13801 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
13802 end Copy_Array_Base_Type_Attributes;
13804 -----------------------------------
13805 -- Copy_Array_Subtype_Attributes --
13806 -----------------------------------
13808 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
13810 Set_Size_Info (T1, T2);
13812 Set_First_Index (T1, First_Index (T2));
13813 Set_Is_Aliased (T1, Is_Aliased (T2));
13814 Set_Is_Volatile (T1, Is_Volatile (T2));
13815 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
13816 Set_Is_Constrained (T1, Is_Constrained (T2));
13817 Set_Depends_On_Private (T1, Has_Private_Component (T2));
13818 Inherit_Rep_Item_Chain (T1, T2);
13819 Set_Convention (T1, Convention (T2));
13820 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
13821 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
13822 Set_Packed_Array_Impl_Type (T1, Packed_Array_Impl_Type (T2));
13823 end Copy_Array_Subtype_Attributes;
13825 -----------------------------------
13826 -- Create_Constrained_Components --
13827 -----------------------------------
13829 procedure Create_Constrained_Components
13831 Decl_Node : Node_Id;
13833 Constraints : Elist_Id)
13835 Loc : constant Source_Ptr := Sloc (Subt);
13836 Comp_List : constant Elist_Id := New_Elmt_List;
13837 Parent_Type : constant Entity_Id := Etype (Typ);
13838 Assoc_List : constant List_Id := New_List;
13839 Discr_Val : Elmt_Id;
13843 Is_Static : Boolean := True;
13845 procedure Collect_Fixed_Components (Typ : Entity_Id);
13846 -- Collect parent type components that do not appear in a variant part
13848 procedure Create_All_Components;
13849 -- Iterate over Comp_List to create the components of the subtype
13851 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
13852 -- Creates a new component from Old_Compon, copying all the fields from
13853 -- it, including its Etype, inserts the new component in the Subt entity
13854 -- chain and returns the new component.
13856 function Is_Variant_Record (T : Entity_Id) return Boolean;
13857 -- If true, and discriminants are static, collect only components from
13858 -- variants selected by discriminant values.
13860 ------------------------------
13861 -- Collect_Fixed_Components --
13862 ------------------------------
13864 procedure Collect_Fixed_Components (Typ : Entity_Id) is
13866 -- Build association list for discriminants, and find components of the
13867 -- variant part selected by the values of the discriminants.
13869 Old_C := First_Discriminant (Typ);
13870 Discr_Val := First_Elmt (Constraints);
13871 while Present (Old_C) loop
13872 Append_To (Assoc_List,
13873 Make_Component_Association (Loc,
13874 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
13875 Expression => New_Copy (Node (Discr_Val))));
13877 Next_Elmt (Discr_Val);
13878 Next_Discriminant (Old_C);
13881 -- The tag and the possible parent component are unconditionally in
13884 if Is_Tagged_Type (Typ) or else Has_Controlled_Component (Typ) then
13885 Old_C := First_Component (Typ);
13886 while Present (Old_C) loop
13887 if Nam_In (Chars (Old_C), Name_uTag, Name_uParent) then
13888 Append_Elmt (Old_C, Comp_List);
13891 Next_Component (Old_C);
13894 end Collect_Fixed_Components;
13896 ---------------------------
13897 -- Create_All_Components --
13898 ---------------------------
13900 procedure Create_All_Components is
13904 Comp := First_Elmt (Comp_List);
13905 while Present (Comp) loop
13906 Old_C := Node (Comp);
13907 New_C := Create_Component (Old_C);
13911 Constrain_Component_Type
13912 (Old_C, Subt, Decl_Node, Typ, Constraints));
13913 Set_Is_Public (New_C, Is_Public (Subt));
13917 end Create_All_Components;
13919 ----------------------
13920 -- Create_Component --
13921 ----------------------
13923 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
13924 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
13927 if Ekind (Old_Compon) = E_Discriminant
13928 and then Is_Completely_Hidden (Old_Compon)
13930 -- This is a shadow discriminant created for a discriminant of
13931 -- the parent type, which needs to be present in the subtype.
13932 -- Give the shadow discriminant an internal name that cannot
13933 -- conflict with that of visible components.
13935 Set_Chars (New_Compon, New_Internal_Name ('C'));
13938 -- Set the parent so we have a proper link for freezing etc. This is
13939 -- not a real parent pointer, since of course our parent does not own
13940 -- up to us and reference us, we are an illegitimate child of the
13941 -- original parent.
13943 Set_Parent (New_Compon, Parent (Old_Compon));
13945 -- If the old component's Esize was already determined and is a
13946 -- static value, then the new component simply inherits it. Otherwise
13947 -- the old component's size may require run-time determination, but
13948 -- the new component's size still might be statically determinable
13949 -- (if, for example it has a static constraint). In that case we want
13950 -- Layout_Type to recompute the component's size, so we reset its
13951 -- size and positional fields.
13953 if Frontend_Layout_On_Target
13954 and then not Known_Static_Esize (Old_Compon)
13956 Set_Esize (New_Compon, Uint_0);
13957 Init_Normalized_First_Bit (New_Compon);
13958 Init_Normalized_Position (New_Compon);
13959 Init_Normalized_Position_Max (New_Compon);
13962 -- We do not want this node marked as Comes_From_Source, since
13963 -- otherwise it would get first class status and a separate cross-
13964 -- reference line would be generated. Illegitimate children do not
13965 -- rate such recognition.
13967 Set_Comes_From_Source (New_Compon, False);
13969 -- But it is a real entity, and a birth certificate must be properly
13970 -- registered by entering it into the entity list.
13972 Enter_Name (New_Compon);
13975 end Create_Component;
13977 -----------------------
13978 -- Is_Variant_Record --
13979 -----------------------
13981 function Is_Variant_Record (T : Entity_Id) return Boolean is
13983 return Nkind (Parent (T)) = N_Full_Type_Declaration
13984 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
13985 and then Present (Component_List (Type_Definition (Parent (T))))
13988 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
13989 end Is_Variant_Record;
13991 -- Start of processing for Create_Constrained_Components
13994 pragma Assert (Subt /= Base_Type (Subt));
13995 pragma Assert (Typ = Base_Type (Typ));
13997 Set_First_Entity (Subt, Empty);
13998 Set_Last_Entity (Subt, Empty);
14000 -- Check whether constraint is fully static, in which case we can
14001 -- optimize the list of components.
14003 Discr_Val := First_Elmt (Constraints);
14004 while Present (Discr_Val) loop
14005 if not Is_OK_Static_Expression (Node (Discr_Val)) then
14006 Is_Static := False;
14010 Next_Elmt (Discr_Val);
14013 Set_Has_Static_Discriminants (Subt, Is_Static);
14017 -- Inherit the discriminants of the parent type
14019 Add_Discriminants : declare
14025 Old_C := First_Discriminant (Typ);
14027 while Present (Old_C) loop
14028 Num_Disc := Num_Disc + 1;
14029 New_C := Create_Component (Old_C);
14030 Set_Is_Public (New_C, Is_Public (Subt));
14031 Next_Discriminant (Old_C);
14034 -- For an untagged derived subtype, the number of discriminants may
14035 -- be smaller than the number of inherited discriminants, because
14036 -- several of them may be renamed by a single new discriminant or
14037 -- constrained. In this case, add the hidden discriminants back into
14038 -- the subtype, because they need to be present if the optimizer of
14039 -- the GCC 4.x back-end decides to break apart assignments between
14040 -- objects using the parent view into member-wise assignments.
14044 if Is_Derived_Type (Typ)
14045 and then not Is_Tagged_Type (Typ)
14047 Old_C := First_Stored_Discriminant (Typ);
14049 while Present (Old_C) loop
14050 Num_Gird := Num_Gird + 1;
14051 Next_Stored_Discriminant (Old_C);
14055 if Num_Gird > Num_Disc then
14057 -- Find out multiple uses of new discriminants, and add hidden
14058 -- components for the extra renamed discriminants. We recognize
14059 -- multiple uses through the Corresponding_Discriminant of a
14060 -- new discriminant: if it constrains several old discriminants,
14061 -- this field points to the last one in the parent type. The
14062 -- stored discriminants of the derived type have the same name
14063 -- as those of the parent.
14067 New_Discr : Entity_Id;
14068 Old_Discr : Entity_Id;
14071 Constr := First_Elmt (Stored_Constraint (Typ));
14072 Old_Discr := First_Stored_Discriminant (Typ);
14073 while Present (Constr) loop
14074 if Is_Entity_Name (Node (Constr))
14075 and then Ekind (Entity (Node (Constr))) = E_Discriminant
14077 New_Discr := Entity (Node (Constr));
14079 if Chars (Corresponding_Discriminant (New_Discr)) /=
14082 -- The new discriminant has been used to rename a
14083 -- subsequent old discriminant. Introduce a shadow
14084 -- component for the current old discriminant.
14086 New_C := Create_Component (Old_Discr);
14087 Set_Original_Record_Component (New_C, Old_Discr);
14091 -- The constraint has eliminated the old discriminant.
14092 -- Introduce a shadow component.
14094 New_C := Create_Component (Old_Discr);
14095 Set_Original_Record_Component (New_C, Old_Discr);
14098 Next_Elmt (Constr);
14099 Next_Stored_Discriminant (Old_Discr);
14103 end Add_Discriminants;
14106 and then Is_Variant_Record (Typ)
14108 Collect_Fixed_Components (Typ);
14110 Gather_Components (
14112 Component_List (Type_Definition (Parent (Typ))),
14113 Governed_By => Assoc_List,
14115 Report_Errors => Errors);
14116 pragma Assert (not Errors);
14118 Create_All_Components;
14120 -- If the subtype declaration is created for a tagged type derivation
14121 -- with constraints, we retrieve the record definition of the parent
14122 -- type to select the components of the proper variant.
14125 and then Is_Tagged_Type (Typ)
14126 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
14128 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
14129 and then Is_Variant_Record (Parent_Type)
14131 Collect_Fixed_Components (Typ);
14135 Component_List (Type_Definition (Parent (Parent_Type))),
14136 Governed_By => Assoc_List,
14138 Report_Errors => Errors);
14140 -- Note: previously there was a check at this point that no errors
14141 -- were detected. As a consequence of AI05-220 there may be an error
14142 -- if an inherited discriminant that controls a variant has a non-
14143 -- static constraint.
14145 -- If the tagged derivation has a type extension, collect all the
14146 -- new components therein.
14148 if Present (Record_Extension_Part (Type_Definition (Parent (Typ))))
14150 Old_C := First_Component (Typ);
14151 while Present (Old_C) loop
14152 if Original_Record_Component (Old_C) = Old_C
14153 and then Chars (Old_C) /= Name_uTag
14154 and then Chars (Old_C) /= Name_uParent
14156 Append_Elmt (Old_C, Comp_List);
14159 Next_Component (Old_C);
14163 Create_All_Components;
14166 -- If discriminants are not static, or if this is a multi-level type
14167 -- extension, we have to include all components of the parent type.
14169 Old_C := First_Component (Typ);
14170 while Present (Old_C) loop
14171 New_C := Create_Component (Old_C);
14175 Constrain_Component_Type
14176 (Old_C, Subt, Decl_Node, Typ, Constraints));
14177 Set_Is_Public (New_C, Is_Public (Subt));
14179 Next_Component (Old_C);
14184 end Create_Constrained_Components;
14186 ------------------------------------------
14187 -- Decimal_Fixed_Point_Type_Declaration --
14188 ------------------------------------------
14190 procedure Decimal_Fixed_Point_Type_Declaration
14194 Loc : constant Source_Ptr := Sloc (Def);
14195 Digs_Expr : constant Node_Id := Digits_Expression (Def);
14196 Delta_Expr : constant Node_Id := Delta_Expression (Def);
14197 Implicit_Base : Entity_Id;
14204 Check_SPARK_05_Restriction
14205 ("decimal fixed point type is not allowed", Def);
14206 Check_Restriction (No_Fixed_Point, Def);
14208 -- Create implicit base type
14211 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
14212 Set_Etype (Implicit_Base, Implicit_Base);
14214 -- Analyze and process delta expression
14216 Analyze_And_Resolve (Delta_Expr, Universal_Real);
14218 Check_Delta_Expression (Delta_Expr);
14219 Delta_Val := Expr_Value_R (Delta_Expr);
14221 -- Check delta is power of 10, and determine scale value from it
14227 Scale_Val := Uint_0;
14230 if Val < Ureal_1 then
14231 while Val < Ureal_1 loop
14232 Val := Val * Ureal_10;
14233 Scale_Val := Scale_Val + 1;
14236 if Scale_Val > 18 then
14237 Error_Msg_N ("scale exceeds maximum value of 18", Def);
14238 Scale_Val := UI_From_Int (+18);
14242 while Val > Ureal_1 loop
14243 Val := Val / Ureal_10;
14244 Scale_Val := Scale_Val - 1;
14247 if Scale_Val < -18 then
14248 Error_Msg_N ("scale is less than minimum value of -18", Def);
14249 Scale_Val := UI_From_Int (-18);
14253 if Val /= Ureal_1 then
14254 Error_Msg_N ("delta expression must be a power of 10", Def);
14255 Delta_Val := Ureal_10 ** (-Scale_Val);
14259 -- Set delta, scale and small (small = delta for decimal type)
14261 Set_Delta_Value (Implicit_Base, Delta_Val);
14262 Set_Scale_Value (Implicit_Base, Scale_Val);
14263 Set_Small_Value (Implicit_Base, Delta_Val);
14265 -- Analyze and process digits expression
14267 Analyze_And_Resolve (Digs_Expr, Any_Integer);
14268 Check_Digits_Expression (Digs_Expr);
14269 Digs_Val := Expr_Value (Digs_Expr);
14271 if Digs_Val > 18 then
14272 Digs_Val := UI_From_Int (+18);
14273 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
14276 Set_Digits_Value (Implicit_Base, Digs_Val);
14277 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
14279 -- Set range of base type from digits value for now. This will be
14280 -- expanded to represent the true underlying base range by Freeze.
14282 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
14284 -- Note: We leave size as zero for now, size will be set at freeze
14285 -- time. We have to do this for ordinary fixed-point, because the size
14286 -- depends on the specified small, and we might as well do the same for
14287 -- decimal fixed-point.
14289 pragma Assert (Esize (Implicit_Base) = Uint_0);
14291 -- If there are bounds given in the declaration use them as the
14292 -- bounds of the first named subtype.
14294 if Present (Real_Range_Specification (Def)) then
14296 RRS : constant Node_Id := Real_Range_Specification (Def);
14297 Low : constant Node_Id := Low_Bound (RRS);
14298 High : constant Node_Id := High_Bound (RRS);
14303 Analyze_And_Resolve (Low, Any_Real);
14304 Analyze_And_Resolve (High, Any_Real);
14305 Check_Real_Bound (Low);
14306 Check_Real_Bound (High);
14307 Low_Val := Expr_Value_R (Low);
14308 High_Val := Expr_Value_R (High);
14310 if Low_Val < (-Bound_Val) then
14312 ("range low bound too small for digits value", Low);
14313 Low_Val := -Bound_Val;
14316 if High_Val > Bound_Val then
14318 ("range high bound too large for digits value", High);
14319 High_Val := Bound_Val;
14322 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
14325 -- If no explicit range, use range that corresponds to given
14326 -- digits value. This will end up as the final range for the
14330 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
14333 -- Complete entity for first subtype. The inheritance of the rep item
14334 -- chain ensures that SPARK-related pragmas are not clobbered when the
14335 -- decimal fixed point type acts as a full view of a private type.
14337 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
14338 Set_Etype (T, Implicit_Base);
14339 Set_Size_Info (T, Implicit_Base);
14340 Inherit_Rep_Item_Chain (T, Implicit_Base);
14341 Set_Digits_Value (T, Digs_Val);
14342 Set_Delta_Value (T, Delta_Val);
14343 Set_Small_Value (T, Delta_Val);
14344 Set_Scale_Value (T, Scale_Val);
14345 Set_Is_Constrained (T);
14346 end Decimal_Fixed_Point_Type_Declaration;
14348 -----------------------------------
14349 -- Derive_Progenitor_Subprograms --
14350 -----------------------------------
14352 procedure Derive_Progenitor_Subprograms
14353 (Parent_Type : Entity_Id;
14354 Tagged_Type : Entity_Id)
14359 Iface_Elmt : Elmt_Id;
14360 Iface_Subp : Entity_Id;
14361 New_Subp : Entity_Id := Empty;
14362 Prim_Elmt : Elmt_Id;
14367 pragma Assert (Ada_Version >= Ada_2005
14368 and then Is_Record_Type (Tagged_Type)
14369 and then Is_Tagged_Type (Tagged_Type)
14370 and then Has_Interfaces (Tagged_Type));
14372 -- Step 1: Transfer to the full-view primitives associated with the
14373 -- partial-view that cover interface primitives. Conceptually this
14374 -- work should be done later by Process_Full_View; done here to
14375 -- simplify its implementation at later stages. It can be safely
14376 -- done here because interfaces must be visible in the partial and
14377 -- private view (RM 7.3(7.3/2)).
14379 -- Small optimization: This work is only required if the parent may
14380 -- have entities whose Alias attribute reference an interface primitive.
14381 -- Such a situation may occur if the parent is an abstract type and the
14382 -- primitive has not been yet overridden or if the parent is a generic
14383 -- formal type covering interfaces.
14385 -- If the tagged type is not abstract, it cannot have abstract
14386 -- primitives (the only entities in the list of primitives of
14387 -- non-abstract tagged types that can reference abstract primitives
14388 -- through its Alias attribute are the internal entities that have
14389 -- attribute Interface_Alias, and these entities are generated later
14390 -- by Add_Internal_Interface_Entities).
14392 if In_Private_Part (Current_Scope)
14393 and then (Is_Abstract_Type (Parent_Type)
14395 Is_Generic_Type (Parent_Type))
14397 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
14398 while Present (Elmt) loop
14399 Subp := Node (Elmt);
14401 -- At this stage it is not possible to have entities in the list
14402 -- of primitives that have attribute Interface_Alias.
14404 pragma Assert (No (Interface_Alias (Subp)));
14406 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
14408 if Is_Interface (Typ) then
14409 E := Find_Primitive_Covering_Interface
14410 (Tagged_Type => Tagged_Type,
14411 Iface_Prim => Subp);
14414 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
14416 Replace_Elmt (Elmt, E);
14417 Remove_Homonym (Subp);
14425 -- Step 2: Add primitives of progenitors that are not implemented by
14426 -- parents of Tagged_Type.
14428 if Present (Interfaces (Base_Type (Tagged_Type))) then
14429 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
14430 while Present (Iface_Elmt) loop
14431 Iface := Node (Iface_Elmt);
14433 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
14434 while Present (Prim_Elmt) loop
14435 Iface_Subp := Node (Prim_Elmt);
14437 -- Exclude derivation of predefined primitives except those
14438 -- that come from source, or are inherited from one that comes
14439 -- from source. Required to catch declarations of equality
14440 -- operators of interfaces. For example:
14442 -- type Iface is interface;
14443 -- function "=" (Left, Right : Iface) return Boolean;
14445 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
14446 or else Comes_From_Source (Ultimate_Alias (Iface_Subp))
14448 E := Find_Primitive_Covering_Interface
14449 (Tagged_Type => Tagged_Type,
14450 Iface_Prim => Iface_Subp);
14452 -- If not found we derive a new primitive leaving its alias
14453 -- attribute referencing the interface primitive.
14457 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14459 -- Ada 2012 (AI05-0197): If the covering primitive's name
14460 -- differs from the name of the interface primitive then it
14461 -- is a private primitive inherited from a parent type. In
14462 -- such case, given that Tagged_Type covers the interface,
14463 -- the inherited private primitive becomes visible. For such
14464 -- purpose we add a new entity that renames the inherited
14465 -- private primitive.
14467 elsif Chars (E) /= Chars (Iface_Subp) then
14468 pragma Assert (Has_Suffix (E, 'P'));
14470 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14471 Set_Alias (New_Subp, E);
14472 Set_Is_Abstract_Subprogram (New_Subp,
14473 Is_Abstract_Subprogram (E));
14475 -- Propagate to the full view interface entities associated
14476 -- with the partial view.
14478 elsif In_Private_Part (Current_Scope)
14479 and then Present (Alias (E))
14480 and then Alias (E) = Iface_Subp
14482 List_Containing (Parent (E)) /=
14483 Private_Declarations
14485 (Unit_Declaration_Node (Current_Scope)))
14487 Append_Elmt (E, Primitive_Operations (Tagged_Type));
14491 Next_Elmt (Prim_Elmt);
14494 Next_Elmt (Iface_Elmt);
14497 end Derive_Progenitor_Subprograms;
14499 -----------------------
14500 -- Derive_Subprogram --
14501 -----------------------
14503 procedure Derive_Subprogram
14504 (New_Subp : in out Entity_Id;
14505 Parent_Subp : Entity_Id;
14506 Derived_Type : Entity_Id;
14507 Parent_Type : Entity_Id;
14508 Actual_Subp : Entity_Id := Empty)
14510 Formal : Entity_Id;
14511 -- Formal parameter of parent primitive operation
14513 Formal_Of_Actual : Entity_Id;
14514 -- Formal parameter of actual operation, when the derivation is to
14515 -- create a renaming for a primitive operation of an actual in an
14518 New_Formal : Entity_Id;
14519 -- Formal of inherited operation
14521 Visible_Subp : Entity_Id := Parent_Subp;
14523 function Is_Private_Overriding return Boolean;
14524 -- If Subp is a private overriding of a visible operation, the inherited
14525 -- operation derives from the overridden op (even though its body is the
14526 -- overriding one) and the inherited operation is visible now. See
14527 -- sem_disp to see the full details of the handling of the overridden
14528 -- subprogram, which is removed from the list of primitive operations of
14529 -- the type. The overridden subprogram is saved locally in Visible_Subp,
14530 -- and used to diagnose abstract operations that need overriding in the
14533 procedure Replace_Type (Id, New_Id : Entity_Id);
14534 -- When the type is an anonymous access type, create a new access type
14535 -- designating the derived type.
14537 procedure Set_Derived_Name;
14538 -- This procedure sets the appropriate Chars name for New_Subp. This
14539 -- is normally just a copy of the parent name. An exception arises for
14540 -- type support subprograms, where the name is changed to reflect the
14541 -- name of the derived type, e.g. if type foo is derived from type bar,
14542 -- then a procedure barDA is derived with a name fooDA.
14544 ---------------------------
14545 -- Is_Private_Overriding --
14546 ---------------------------
14548 function Is_Private_Overriding return Boolean is
14552 -- If the parent is not a dispatching operation there is no
14553 -- need to investigate overridings
14555 if not Is_Dispatching_Operation (Parent_Subp) then
14559 -- The visible operation that is overridden is a homonym of the
14560 -- parent subprogram. We scan the homonym chain to find the one
14561 -- whose alias is the subprogram we are deriving.
14563 Prev := Current_Entity (Parent_Subp);
14564 while Present (Prev) loop
14565 if Ekind (Prev) = Ekind (Parent_Subp)
14566 and then Alias (Prev) = Parent_Subp
14567 and then Scope (Parent_Subp) = Scope (Prev)
14568 and then not Is_Hidden (Prev)
14570 Visible_Subp := Prev;
14574 Prev := Homonym (Prev);
14578 end Is_Private_Overriding;
14584 procedure Replace_Type (Id, New_Id : Entity_Id) is
14585 Id_Type : constant Entity_Id := Etype (Id);
14586 Acc_Type : Entity_Id;
14587 Par : constant Node_Id := Parent (Derived_Type);
14590 -- When the type is an anonymous access type, create a new access
14591 -- type designating the derived type. This itype must be elaborated
14592 -- at the point of the derivation, not on subsequent calls that may
14593 -- be out of the proper scope for Gigi, so we insert a reference to
14594 -- it after the derivation.
14596 if Ekind (Id_Type) = E_Anonymous_Access_Type then
14598 Desig_Typ : Entity_Id := Designated_Type (Id_Type);
14601 if Ekind (Desig_Typ) = E_Record_Type_With_Private
14602 and then Present (Full_View (Desig_Typ))
14603 and then not Is_Private_Type (Parent_Type)
14605 Desig_Typ := Full_View (Desig_Typ);
14608 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
14610 -- Ada 2005 (AI-251): Handle also derivations of abstract
14611 -- interface primitives.
14613 or else (Is_Interface (Desig_Typ)
14614 and then not Is_Class_Wide_Type (Desig_Typ))
14616 Acc_Type := New_Copy (Id_Type);
14617 Set_Etype (Acc_Type, Acc_Type);
14618 Set_Scope (Acc_Type, New_Subp);
14620 -- Set size of anonymous access type. If we have an access
14621 -- to an unconstrained array, this is a fat pointer, so it
14622 -- is sizes at twice addtress size.
14624 if Is_Array_Type (Desig_Typ)
14625 and then not Is_Constrained (Desig_Typ)
14627 Init_Size (Acc_Type, 2 * System_Address_Size);
14629 -- Other cases use a thin pointer
14632 Init_Size (Acc_Type, System_Address_Size);
14635 -- Set remaining characterstics of anonymous access type
14637 Init_Alignment (Acc_Type);
14638 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
14640 Set_Etype (New_Id, Acc_Type);
14641 Set_Scope (New_Id, New_Subp);
14643 -- Create a reference to it
14645 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
14648 Set_Etype (New_Id, Id_Type);
14652 -- In Ada2012, a formal may have an incomplete type but the type
14653 -- derivation that inherits the primitive follows the full view.
14655 elsif Base_Type (Id_Type) = Base_Type (Parent_Type)
14657 (Ekind (Id_Type) = E_Record_Type_With_Private
14658 and then Present (Full_View (Id_Type))
14660 Base_Type (Full_View (Id_Type)) = Base_Type (Parent_Type))
14662 (Ada_Version >= Ada_2012
14663 and then Ekind (Id_Type) = E_Incomplete_Type
14664 and then Full_View (Id_Type) = Parent_Type)
14666 -- Constraint checks on formals are generated during expansion,
14667 -- based on the signature of the original subprogram. The bounds
14668 -- of the derived type are not relevant, and thus we can use
14669 -- the base type for the formals. However, the return type may be
14670 -- used in a context that requires that the proper static bounds
14671 -- be used (a case statement, for example) and for those cases
14672 -- we must use the derived type (first subtype), not its base.
14674 -- If the derived_type_definition has no constraints, we know that
14675 -- the derived type has the same constraints as the first subtype
14676 -- of the parent, and we can also use it rather than its base,
14677 -- which can lead to more efficient code.
14679 if Etype (Id) = Parent_Type then
14680 if Is_Scalar_Type (Parent_Type)
14682 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
14684 Set_Etype (New_Id, Derived_Type);
14686 elsif Nkind (Par) = N_Full_Type_Declaration
14688 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
14691 (Subtype_Indication (Type_Definition (Par)))
14693 Set_Etype (New_Id, Derived_Type);
14696 Set_Etype (New_Id, Base_Type (Derived_Type));
14700 Set_Etype (New_Id, Base_Type (Derived_Type));
14704 Set_Etype (New_Id, Etype (Id));
14708 ----------------------
14709 -- Set_Derived_Name --
14710 ----------------------
14712 procedure Set_Derived_Name is
14713 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
14715 if Nm = TSS_Null then
14716 Set_Chars (New_Subp, Chars (Parent_Subp));
14718 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
14720 end Set_Derived_Name;
14722 -- Start of processing for Derive_Subprogram
14725 New_Subp := New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
14726 Set_Ekind (New_Subp, Ekind (Parent_Subp));
14728 -- Check whether the inherited subprogram is a private operation that
14729 -- should be inherited but not yet made visible. Such subprograms can
14730 -- become visible at a later point (e.g., the private part of a public
14731 -- child unit) via Declare_Inherited_Private_Subprograms. If the
14732 -- following predicate is true, then this is not such a private
14733 -- operation and the subprogram simply inherits the name of the parent
14734 -- subprogram. Note the special check for the names of controlled
14735 -- operations, which are currently exempted from being inherited with
14736 -- a hidden name because they must be findable for generation of
14737 -- implicit run-time calls.
14739 if not Is_Hidden (Parent_Subp)
14740 or else Is_Internal (Parent_Subp)
14741 or else Is_Private_Overriding
14742 or else Is_Internal_Name (Chars (Parent_Subp))
14743 or else Nam_In (Chars (Parent_Subp), Name_Initialize,
14749 -- An inherited dispatching equality will be overridden by an internally
14750 -- generated one, or by an explicit one, so preserve its name and thus
14751 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
14752 -- private operation it may become invisible if the full view has
14753 -- progenitors, and the dispatch table will be malformed.
14754 -- We check that the type is limited to handle the anomalous declaration
14755 -- of Limited_Controlled, which is derived from a non-limited type, and
14756 -- which is handled specially elsewhere as well.
14758 elsif Chars (Parent_Subp) = Name_Op_Eq
14759 and then Is_Dispatching_Operation (Parent_Subp)
14760 and then Etype (Parent_Subp) = Standard_Boolean
14761 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
14763 Etype (First_Formal (Parent_Subp)) =
14764 Etype (Next_Formal (First_Formal (Parent_Subp)))
14768 -- If parent is hidden, this can be a regular derivation if the
14769 -- parent is immediately visible in a non-instantiating context,
14770 -- or if we are in the private part of an instance. This test
14771 -- should still be refined ???
14773 -- The test for In_Instance_Not_Visible avoids inheriting the derived
14774 -- operation as a non-visible operation in cases where the parent
14775 -- subprogram might not be visible now, but was visible within the
14776 -- original generic, so it would be wrong to make the inherited
14777 -- subprogram non-visible now. (Not clear if this test is fully
14778 -- correct; are there any cases where we should declare the inherited
14779 -- operation as not visible to avoid it being overridden, e.g., when
14780 -- the parent type is a generic actual with private primitives ???)
14782 -- (they should be treated the same as other private inherited
14783 -- subprograms, but it's not clear how to do this cleanly). ???
14785 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
14786 and then Is_Immediately_Visible (Parent_Subp)
14787 and then not In_Instance)
14788 or else In_Instance_Not_Visible
14792 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
14793 -- overrides an interface primitive because interface primitives
14794 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
14796 elsif Ada_Version >= Ada_2005
14797 and then Is_Dispatching_Operation (Parent_Subp)
14798 and then Covers_Some_Interface (Parent_Subp)
14802 -- Otherwise, the type is inheriting a private operation, so enter
14803 -- it with a special name so it can't be overridden.
14806 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
14809 Set_Parent (New_Subp, Parent (Derived_Type));
14811 if Present (Actual_Subp) then
14812 Replace_Type (Actual_Subp, New_Subp);
14814 Replace_Type (Parent_Subp, New_Subp);
14817 Conditional_Delay (New_Subp, Parent_Subp);
14819 -- If we are creating a renaming for a primitive operation of an
14820 -- actual of a generic derived type, we must examine the signature
14821 -- of the actual primitive, not that of the generic formal, which for
14822 -- example may be an interface. However the name and initial value
14823 -- of the inherited operation are those of the formal primitive.
14825 Formal := First_Formal (Parent_Subp);
14827 if Present (Actual_Subp) then
14828 Formal_Of_Actual := First_Formal (Actual_Subp);
14830 Formal_Of_Actual := Empty;
14833 while Present (Formal) loop
14834 New_Formal := New_Copy (Formal);
14836 -- Normally we do not go copying parents, but in the case of
14837 -- formals, we need to link up to the declaration (which is the
14838 -- parameter specification), and it is fine to link up to the
14839 -- original formal's parameter specification in this case.
14841 Set_Parent (New_Formal, Parent (Formal));
14842 Append_Entity (New_Formal, New_Subp);
14844 if Present (Formal_Of_Actual) then
14845 Replace_Type (Formal_Of_Actual, New_Formal);
14846 Next_Formal (Formal_Of_Actual);
14848 Replace_Type (Formal, New_Formal);
14851 Next_Formal (Formal);
14854 -- If this derivation corresponds to a tagged generic actual, then
14855 -- primitive operations rename those of the actual. Otherwise the
14856 -- primitive operations rename those of the parent type, If the parent
14857 -- renames an intrinsic operator, so does the new subprogram. We except
14858 -- concatenation, which is always properly typed, and does not get
14859 -- expanded as other intrinsic operations.
14861 if No (Actual_Subp) then
14862 if Is_Intrinsic_Subprogram (Parent_Subp) then
14863 Set_Is_Intrinsic_Subprogram (New_Subp);
14865 if Present (Alias (Parent_Subp))
14866 and then Chars (Parent_Subp) /= Name_Op_Concat
14868 Set_Alias (New_Subp, Alias (Parent_Subp));
14870 Set_Alias (New_Subp, Parent_Subp);
14874 Set_Alias (New_Subp, Parent_Subp);
14878 Set_Alias (New_Subp, Actual_Subp);
14881 -- Inherit the "ghostness" from the parent subprogram
14883 if Is_Ghost_Entity (Alias (New_Subp)) then
14884 Set_Is_Ghost_Entity (New_Subp);
14887 -- Derived subprograms of a tagged type must inherit the convention
14888 -- of the parent subprogram (a requirement of AI-117). Derived
14889 -- subprograms of untagged types simply get convention Ada by default.
14891 -- If the derived type is a tagged generic formal type with unknown
14892 -- discriminants, its convention is intrinsic (RM 6.3.1 (8)).
14894 -- However, if the type is derived from a generic formal, the further
14895 -- inherited subprogram has the convention of the non-generic ancestor.
14896 -- Otherwise there would be no way to override the operation.
14897 -- (This is subject to forthcoming ARG discussions).
14899 if Is_Tagged_Type (Derived_Type) then
14900 if Is_Generic_Type (Derived_Type)
14901 and then Has_Unknown_Discriminants (Derived_Type)
14903 Set_Convention (New_Subp, Convention_Intrinsic);
14906 if Is_Generic_Type (Parent_Type)
14907 and then Has_Unknown_Discriminants (Parent_Type)
14909 Set_Convention (New_Subp, Convention (Alias (Parent_Subp)));
14911 Set_Convention (New_Subp, Convention (Parent_Subp));
14916 -- Predefined controlled operations retain their name even if the parent
14917 -- is hidden (see above), but they are not primitive operations if the
14918 -- ancestor is not visible, for example if the parent is a private
14919 -- extension completed with a controlled extension. Note that a full
14920 -- type that is controlled can break privacy: the flag Is_Controlled is
14921 -- set on both views of the type.
14923 if Is_Controlled (Parent_Type)
14924 and then Nam_In (Chars (Parent_Subp), Name_Initialize,
14927 and then Is_Hidden (Parent_Subp)
14928 and then not Is_Visibly_Controlled (Parent_Type)
14930 Set_Is_Hidden (New_Subp);
14933 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
14934 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
14936 if Ekind (Parent_Subp) = E_Procedure then
14937 Set_Is_Valued_Procedure
14938 (New_Subp, Is_Valued_Procedure (Parent_Subp));
14940 Set_Has_Controlling_Result
14941 (New_Subp, Has_Controlling_Result (Parent_Subp));
14944 -- No_Return must be inherited properly. If this is overridden in the
14945 -- case of a dispatching operation, then a check is made in Sem_Disp
14946 -- that the overriding operation is also No_Return (no such check is
14947 -- required for the case of non-dispatching operation.
14949 Set_No_Return (New_Subp, No_Return (Parent_Subp));
14951 -- A derived function with a controlling result is abstract. If the
14952 -- Derived_Type is a nonabstract formal generic derived type, then
14953 -- inherited operations are not abstract: the required check is done at
14954 -- instantiation time. If the derivation is for a generic actual, the
14955 -- function is not abstract unless the actual is.
14957 if Is_Generic_Type (Derived_Type)
14958 and then not Is_Abstract_Type (Derived_Type)
14962 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
14963 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
14965 -- A subprogram subject to pragma Extensions_Visible with value False
14966 -- requires overriding if the subprogram has at least one controlling
14967 -- OUT parameter (SPARK RM 6.1.7(6)).
14969 elsif Ada_Version >= Ada_2005
14970 and then (Is_Abstract_Subprogram (Alias (New_Subp))
14971 or else (Is_Tagged_Type (Derived_Type)
14972 and then Etype (New_Subp) = Derived_Type
14973 and then not Is_Null_Extension (Derived_Type))
14974 or else (Is_Tagged_Type (Derived_Type)
14975 and then Ekind (Etype (New_Subp)) =
14976 E_Anonymous_Access_Type
14977 and then Designated_Type (Etype (New_Subp)) =
14979 and then not Is_Null_Extension (Derived_Type))
14980 or else (Comes_From_Source (Alias (New_Subp))
14981 and then Is_EVF_Procedure (Alias (New_Subp))))
14982 and then No (Actual_Subp)
14984 if not Is_Tagged_Type (Derived_Type)
14985 or else Is_Abstract_Type (Derived_Type)
14986 or else Is_Abstract_Subprogram (Alias (New_Subp))
14988 Set_Is_Abstract_Subprogram (New_Subp);
14990 Set_Requires_Overriding (New_Subp);
14993 elsif Ada_Version < Ada_2005
14994 and then (Is_Abstract_Subprogram (Alias (New_Subp))
14995 or else (Is_Tagged_Type (Derived_Type)
14996 and then Etype (New_Subp) = Derived_Type
14997 and then No (Actual_Subp)))
14999 Set_Is_Abstract_Subprogram (New_Subp);
15001 -- AI05-0097 : an inherited operation that dispatches on result is
15002 -- abstract if the derived type is abstract, even if the parent type
15003 -- is concrete and the derived type is a null extension.
15005 elsif Has_Controlling_Result (Alias (New_Subp))
15006 and then Is_Abstract_Type (Etype (New_Subp))
15008 Set_Is_Abstract_Subprogram (New_Subp);
15010 -- Finally, if the parent type is abstract we must verify that all
15011 -- inherited operations are either non-abstract or overridden, or that
15012 -- the derived type itself is abstract (this check is performed at the
15013 -- end of a package declaration, in Check_Abstract_Overriding). A
15014 -- private overriding in the parent type will not be visible in the
15015 -- derivation if we are not in an inner package or in a child unit of
15016 -- the parent type, in which case the abstractness of the inherited
15017 -- operation is carried to the new subprogram.
15019 elsif Is_Abstract_Type (Parent_Type)
15020 and then not In_Open_Scopes (Scope (Parent_Type))
15021 and then Is_Private_Overriding
15022 and then Is_Abstract_Subprogram (Visible_Subp)
15024 if No (Actual_Subp) then
15025 Set_Alias (New_Subp, Visible_Subp);
15026 Set_Is_Abstract_Subprogram (New_Subp, True);
15029 -- If this is a derivation for an instance of a formal derived
15030 -- type, abstractness comes from the primitive operation of the
15031 -- actual, not from the operation inherited from the ancestor.
15033 Set_Is_Abstract_Subprogram
15034 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
15038 New_Overloaded_Entity (New_Subp, Derived_Type);
15040 -- Check for case of a derived subprogram for the instantiation of a
15041 -- formal derived tagged type, if so mark the subprogram as dispatching
15042 -- and inherit the dispatching attributes of the actual subprogram. The
15043 -- derived subprogram is effectively renaming of the actual subprogram,
15044 -- so it needs to have the same attributes as the actual.
15046 if Present (Actual_Subp)
15047 and then Is_Dispatching_Operation (Actual_Subp)
15049 Set_Is_Dispatching_Operation (New_Subp);
15051 if Present (DTC_Entity (Actual_Subp)) then
15052 Set_DTC_Entity (New_Subp, DTC_Entity (Actual_Subp));
15053 Set_DT_Position_Value (New_Subp, DT_Position (Actual_Subp));
15057 -- Indicate that a derived subprogram does not require a body and that
15058 -- it does not require processing of default expressions.
15060 Set_Has_Completion (New_Subp);
15061 Set_Default_Expressions_Processed (New_Subp);
15063 if Ekind (New_Subp) = E_Function then
15064 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
15066 end Derive_Subprogram;
15068 ------------------------
15069 -- Derive_Subprograms --
15070 ------------------------
15072 procedure Derive_Subprograms
15073 (Parent_Type : Entity_Id;
15074 Derived_Type : Entity_Id;
15075 Generic_Actual : Entity_Id := Empty)
15077 Op_List : constant Elist_Id :=
15078 Collect_Primitive_Operations (Parent_Type);
15080 function Check_Derived_Type return Boolean;
15081 -- Check that all the entities derived from Parent_Type are found in
15082 -- the list of primitives of Derived_Type exactly in the same order.
15084 procedure Derive_Interface_Subprogram
15085 (New_Subp : in out Entity_Id;
15087 Actual_Subp : Entity_Id);
15088 -- Derive New_Subp from the ultimate alias of the parent subprogram Subp
15089 -- (which is an interface primitive). If Generic_Actual is present then
15090 -- Actual_Subp is the actual subprogram corresponding with the generic
15091 -- subprogram Subp.
15093 function Check_Derived_Type return Boolean is
15097 New_Subp : Entity_Id;
15102 -- Traverse list of entities in the current scope searching for
15103 -- an incomplete type whose full-view is derived type
15105 E := First_Entity (Scope (Derived_Type));
15106 while Present (E) and then E /= Derived_Type loop
15107 if Ekind (E) = E_Incomplete_Type
15108 and then Present (Full_View (E))
15109 and then Full_View (E) = Derived_Type
15111 -- Disable this test if Derived_Type completes an incomplete
15112 -- type because in such case more primitives can be added
15113 -- later to the list of primitives of Derived_Type by routine
15114 -- Process_Incomplete_Dependents
15119 E := Next_Entity (E);
15122 List := Collect_Primitive_Operations (Derived_Type);
15123 Elmt := First_Elmt (List);
15125 Op_Elmt := First_Elmt (Op_List);
15126 while Present (Op_Elmt) loop
15127 Subp := Node (Op_Elmt);
15128 New_Subp := Node (Elmt);
15130 -- At this early stage Derived_Type has no entities with attribute
15131 -- Interface_Alias. In addition, such primitives are always
15132 -- located at the end of the list of primitives of Parent_Type.
15133 -- Therefore, if found we can safely stop processing pending
15136 exit when Present (Interface_Alias (Subp));
15138 -- Handle hidden entities
15140 if not Is_Predefined_Dispatching_Operation (Subp)
15141 and then Is_Hidden (Subp)
15143 if Present (New_Subp)
15144 and then Primitive_Names_Match (Subp, New_Subp)
15150 if not Present (New_Subp)
15151 or else Ekind (Subp) /= Ekind (New_Subp)
15152 or else not Primitive_Names_Match (Subp, New_Subp)
15160 Next_Elmt (Op_Elmt);
15164 end Check_Derived_Type;
15166 ---------------------------------
15167 -- Derive_Interface_Subprogram --
15168 ---------------------------------
15170 procedure Derive_Interface_Subprogram
15171 (New_Subp : in out Entity_Id;
15173 Actual_Subp : Entity_Id)
15175 Iface_Subp : constant Entity_Id := Ultimate_Alias (Subp);
15176 Iface_Type : constant Entity_Id := Find_Dispatching_Type (Iface_Subp);
15179 pragma Assert (Is_Interface (Iface_Type));
15182 (New_Subp => New_Subp,
15183 Parent_Subp => Iface_Subp,
15184 Derived_Type => Derived_Type,
15185 Parent_Type => Iface_Type,
15186 Actual_Subp => Actual_Subp);
15188 -- Given that this new interface entity corresponds with a primitive
15189 -- of the parent that was not overridden we must leave it associated
15190 -- with its parent primitive to ensure that it will share the same
15191 -- dispatch table slot when overridden.
15193 if No (Actual_Subp) then
15194 Set_Alias (New_Subp, Subp);
15196 -- For instantiations this is not needed since the previous call to
15197 -- Derive_Subprogram leaves the entity well decorated.
15200 pragma Assert (Alias (New_Subp) = Actual_Subp);
15203 end Derive_Interface_Subprogram;
15207 Alias_Subp : Entity_Id;
15208 Act_List : Elist_Id;
15209 Act_Elmt : Elmt_Id;
15210 Act_Subp : Entity_Id := Empty;
15212 Need_Search : Boolean := False;
15213 New_Subp : Entity_Id := Empty;
15214 Parent_Base : Entity_Id;
15217 -- Start of processing for Derive_Subprograms
15220 if Ekind (Parent_Type) = E_Record_Type_With_Private
15221 and then Has_Discriminants (Parent_Type)
15222 and then Present (Full_View (Parent_Type))
15224 Parent_Base := Full_View (Parent_Type);
15226 Parent_Base := Parent_Type;
15229 if Present (Generic_Actual) then
15230 Act_List := Collect_Primitive_Operations (Generic_Actual);
15231 Act_Elmt := First_Elmt (Act_List);
15233 Act_List := No_Elist;
15234 Act_Elmt := No_Elmt;
15237 -- Derive primitives inherited from the parent. Note that if the generic
15238 -- actual is present, this is not really a type derivation, it is a
15239 -- completion within an instance.
15241 -- Case 1: Derived_Type does not implement interfaces
15243 if not Is_Tagged_Type (Derived_Type)
15244 or else (not Has_Interfaces (Derived_Type)
15245 and then not (Present (Generic_Actual)
15246 and then Has_Interfaces (Generic_Actual)))
15248 Elmt := First_Elmt (Op_List);
15249 while Present (Elmt) loop
15250 Subp := Node (Elmt);
15252 -- Literals are derived earlier in the process of building the
15253 -- derived type, and are skipped here.
15255 if Ekind (Subp) = E_Enumeration_Literal then
15258 -- The actual is a direct descendant and the common primitive
15259 -- operations appear in the same order.
15261 -- If the generic parent type is present, the derived type is an
15262 -- instance of a formal derived type, and within the instance its
15263 -- operations are those of the actual. We derive from the formal
15264 -- type but make the inherited operations aliases of the
15265 -- corresponding operations of the actual.
15268 pragma Assert (No (Node (Act_Elmt))
15269 or else (Primitive_Names_Match (Subp, Node (Act_Elmt))
15272 (Subp, Node (Act_Elmt),
15273 Skip_Controlling_Formals => True)));
15276 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
15278 if Present (Act_Elmt) then
15279 Next_Elmt (Act_Elmt);
15286 -- Case 2: Derived_Type implements interfaces
15289 -- If the parent type has no predefined primitives we remove
15290 -- predefined primitives from the list of primitives of generic
15291 -- actual to simplify the complexity of this algorithm.
15293 if Present (Generic_Actual) then
15295 Has_Predefined_Primitives : Boolean := False;
15298 -- Check if the parent type has predefined primitives
15300 Elmt := First_Elmt (Op_List);
15301 while Present (Elmt) loop
15302 Subp := Node (Elmt);
15304 if Is_Predefined_Dispatching_Operation (Subp)
15305 and then not Comes_From_Source (Ultimate_Alias (Subp))
15307 Has_Predefined_Primitives := True;
15314 -- Remove predefined primitives of Generic_Actual. We must use
15315 -- an auxiliary list because in case of tagged types the value
15316 -- returned by Collect_Primitive_Operations is the value stored
15317 -- in its Primitive_Operations attribute (and we don't want to
15318 -- modify its current contents).
15320 if not Has_Predefined_Primitives then
15322 Aux_List : constant Elist_Id := New_Elmt_List;
15325 Elmt := First_Elmt (Act_List);
15326 while Present (Elmt) loop
15327 Subp := Node (Elmt);
15329 if not Is_Predefined_Dispatching_Operation (Subp)
15330 or else Comes_From_Source (Subp)
15332 Append_Elmt (Subp, Aux_List);
15338 Act_List := Aux_List;
15342 Act_Elmt := First_Elmt (Act_List);
15343 Act_Subp := Node (Act_Elmt);
15347 -- Stage 1: If the generic actual is not present we derive the
15348 -- primitives inherited from the parent type. If the generic parent
15349 -- type is present, the derived type is an instance of a formal
15350 -- derived type, and within the instance its operations are those of
15351 -- the actual. We derive from the formal type but make the inherited
15352 -- operations aliases of the corresponding operations of the actual.
15354 Elmt := First_Elmt (Op_List);
15355 while Present (Elmt) loop
15356 Subp := Node (Elmt);
15357 Alias_Subp := Ultimate_Alias (Subp);
15359 -- Do not derive internal entities of the parent that link
15360 -- interface primitives with their covering primitive. These
15361 -- entities will be added to this type when frozen.
15363 if Present (Interface_Alias (Subp)) then
15367 -- If the generic actual is present find the corresponding
15368 -- operation in the generic actual. If the parent type is a
15369 -- direct ancestor of the derived type then, even if it is an
15370 -- interface, the operations are inherited from the primary
15371 -- dispatch table and are in the proper order. If we detect here
15372 -- that primitives are not in the same order we traverse the list
15373 -- of primitive operations of the actual to find the one that
15374 -- implements the interface primitive.
15378 (Present (Generic_Actual)
15379 and then Present (Act_Subp)
15381 (Primitive_Names_Match (Subp, Act_Subp)
15383 Type_Conformant (Subp, Act_Subp,
15384 Skip_Controlling_Formals => True)))
15386 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual,
15387 Use_Full_View => True));
15389 -- Remember that we need searching for all pending primitives
15391 Need_Search := True;
15393 -- Handle entities associated with interface primitives
15395 if Present (Alias_Subp)
15396 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
15397 and then not Is_Predefined_Dispatching_Operation (Subp)
15399 -- Search for the primitive in the homonym chain
15402 Find_Primitive_Covering_Interface
15403 (Tagged_Type => Generic_Actual,
15404 Iface_Prim => Alias_Subp);
15406 -- Previous search may not locate primitives covering
15407 -- interfaces defined in generics units or instantiations.
15408 -- (it fails if the covering primitive has formals whose
15409 -- type is also defined in generics or instantiations).
15410 -- In such case we search in the list of primitives of the
15411 -- generic actual for the internal entity that links the
15412 -- interface primitive and the covering primitive.
15415 and then Is_Generic_Type (Parent_Type)
15417 -- This code has been designed to handle only generic
15418 -- formals that implement interfaces that are defined
15419 -- in a generic unit or instantiation. If this code is
15420 -- needed for other cases we must review it because
15421 -- (given that it relies on Original_Location to locate
15422 -- the primitive of Generic_Actual that covers the
15423 -- interface) it could leave linked through attribute
15424 -- Alias entities of unrelated instantiations).
15428 (Scope (Find_Dispatching_Type (Alias_Subp)))
15430 Instantiation_Depth
15431 (Sloc (Find_Dispatching_Type (Alias_Subp))) > 0);
15434 Iface_Prim_Loc : constant Source_Ptr :=
15435 Original_Location (Sloc (Alias_Subp));
15442 First_Elmt (Primitive_Operations (Generic_Actual));
15444 Search : while Present (Elmt) loop
15445 Prim := Node (Elmt);
15447 if Present (Interface_Alias (Prim))
15448 and then Original_Location
15449 (Sloc (Interface_Alias (Prim))) =
15452 Act_Subp := Alias (Prim);
15461 pragma Assert (Present (Act_Subp)
15462 or else Is_Abstract_Type (Generic_Actual)
15463 or else Serious_Errors_Detected > 0);
15465 -- Handle predefined primitives plus the rest of user-defined
15469 Act_Elmt := First_Elmt (Act_List);
15470 while Present (Act_Elmt) loop
15471 Act_Subp := Node (Act_Elmt);
15473 exit when Primitive_Names_Match (Subp, Act_Subp)
15474 and then Type_Conformant
15476 Skip_Controlling_Formals => True)
15477 and then No (Interface_Alias (Act_Subp));
15479 Next_Elmt (Act_Elmt);
15482 if No (Act_Elmt) then
15488 -- Case 1: If the parent is a limited interface then it has the
15489 -- predefined primitives of synchronized interfaces. However, the
15490 -- actual type may be a non-limited type and hence it does not
15491 -- have such primitives.
15493 if Present (Generic_Actual)
15494 and then not Present (Act_Subp)
15495 and then Is_Limited_Interface (Parent_Base)
15496 and then Is_Predefined_Interface_Primitive (Subp)
15500 -- Case 2: Inherit entities associated with interfaces that were
15501 -- not covered by the parent type. We exclude here null interface
15502 -- primitives because they do not need special management.
15504 -- We also exclude interface operations that are renamings. If the
15505 -- subprogram is an explicit renaming of an interface primitive,
15506 -- it is a regular primitive operation, and the presence of its
15507 -- alias is not relevant: it has to be derived like any other
15510 elsif Present (Alias (Subp))
15511 and then Nkind (Unit_Declaration_Node (Subp)) /=
15512 N_Subprogram_Renaming_Declaration
15513 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
15515 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
15516 and then Null_Present (Parent (Alias_Subp)))
15518 -- If this is an abstract private type then we transfer the
15519 -- derivation of the interface primitive from the partial view
15520 -- to the full view. This is safe because all the interfaces
15521 -- must be visible in the partial view. Done to avoid adding
15522 -- a new interface derivation to the private part of the
15523 -- enclosing package; otherwise this new derivation would be
15524 -- decorated as hidden when the analysis of the enclosing
15525 -- package completes.
15527 if Is_Abstract_Type (Derived_Type)
15528 and then In_Private_Part (Current_Scope)
15529 and then Has_Private_Declaration (Derived_Type)
15532 Partial_View : Entity_Id;
15537 Partial_View := First_Entity (Current_Scope);
15539 exit when No (Partial_View)
15540 or else (Has_Private_Declaration (Partial_View)
15542 Full_View (Partial_View) = Derived_Type);
15544 Next_Entity (Partial_View);
15547 -- If the partial view was not found then the source code
15548 -- has errors and the derivation is not needed.
15550 if Present (Partial_View) then
15552 First_Elmt (Primitive_Operations (Partial_View));
15553 while Present (Elmt) loop
15554 Ent := Node (Elmt);
15556 if Present (Alias (Ent))
15557 and then Ultimate_Alias (Ent) = Alias (Subp)
15560 (Ent, Primitive_Operations (Derived_Type));
15567 -- If the interface primitive was not found in the
15568 -- partial view then this interface primitive was
15569 -- overridden. We add a derivation to activate in
15570 -- Derive_Progenitor_Subprograms the machinery to
15574 Derive_Interface_Subprogram
15575 (New_Subp => New_Subp,
15577 Actual_Subp => Act_Subp);
15582 Derive_Interface_Subprogram
15583 (New_Subp => New_Subp,
15585 Actual_Subp => Act_Subp);
15588 -- Case 3: Common derivation
15592 (New_Subp => New_Subp,
15593 Parent_Subp => Subp,
15594 Derived_Type => Derived_Type,
15595 Parent_Type => Parent_Base,
15596 Actual_Subp => Act_Subp);
15599 -- No need to update Act_Elm if we must search for the
15600 -- corresponding operation in the generic actual
15603 and then Present (Act_Elmt)
15605 Next_Elmt (Act_Elmt);
15606 Act_Subp := Node (Act_Elmt);
15613 -- Inherit additional operations from progenitors. If the derived
15614 -- type is a generic actual, there are not new primitive operations
15615 -- for the type because it has those of the actual, and therefore
15616 -- nothing needs to be done. The renamings generated above are not
15617 -- primitive operations, and their purpose is simply to make the
15618 -- proper operations visible within an instantiation.
15620 if No (Generic_Actual) then
15621 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
15625 -- Final check: Direct descendants must have their primitives in the
15626 -- same order. We exclude from this test untagged types and instances
15627 -- of formal derived types. We skip this test if we have already
15628 -- reported serious errors in the sources.
15630 pragma Assert (not Is_Tagged_Type (Derived_Type)
15631 or else Present (Generic_Actual)
15632 or else Serious_Errors_Detected > 0
15633 or else Check_Derived_Type);
15634 end Derive_Subprograms;
15636 --------------------------------
15637 -- Derived_Standard_Character --
15638 --------------------------------
15640 procedure Derived_Standard_Character
15642 Parent_Type : Entity_Id;
15643 Derived_Type : Entity_Id)
15645 Loc : constant Source_Ptr := Sloc (N);
15646 Def : constant Node_Id := Type_Definition (N);
15647 Indic : constant Node_Id := Subtype_Indication (Def);
15648 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
15649 Implicit_Base : constant Entity_Id :=
15651 (E_Enumeration_Type, N, Derived_Type, 'B');
15657 Discard_Node (Process_Subtype (Indic, N));
15659 Set_Etype (Implicit_Base, Parent_Base);
15660 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
15661 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
15663 Set_Is_Character_Type (Implicit_Base, True);
15664 Set_Has_Delayed_Freeze (Implicit_Base);
15666 -- The bounds of the implicit base are the bounds of the parent base.
15667 -- Note that their type is the parent base.
15669 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
15670 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
15672 Set_Scalar_Range (Implicit_Base,
15675 High_Bound => Hi));
15677 Conditional_Delay (Derived_Type, Parent_Type);
15679 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
15680 Set_Etype (Derived_Type, Implicit_Base);
15681 Set_Size_Info (Derived_Type, Parent_Type);
15683 if Unknown_RM_Size (Derived_Type) then
15684 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
15687 Set_Is_Character_Type (Derived_Type, True);
15689 if Nkind (Indic) /= N_Subtype_Indication then
15691 -- If no explicit constraint, the bounds are those
15692 -- of the parent type.
15694 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
15695 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
15696 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
15699 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
15701 -- Because the implicit base is used in the conversion of the bounds, we
15702 -- have to freeze it now. This is similar to what is done for numeric
15703 -- types, and it equally suspicious, but otherwise a non-static bound
15704 -- will have a reference to an unfrozen type, which is rejected by Gigi
15705 -- (???). This requires specific care for definition of stream
15706 -- attributes. For details, see comments at the end of
15707 -- Build_Derived_Numeric_Type.
15709 Freeze_Before (N, Implicit_Base);
15710 end Derived_Standard_Character;
15712 ------------------------------
15713 -- Derived_Type_Declaration --
15714 ------------------------------
15716 procedure Derived_Type_Declaration
15719 Is_Completion : Boolean)
15721 Parent_Type : Entity_Id;
15723 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
15724 -- Check whether the parent type is a generic formal, or derives
15725 -- directly or indirectly from one.
15727 ------------------------
15728 -- Comes_From_Generic --
15729 ------------------------
15731 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
15733 if Is_Generic_Type (Typ) then
15736 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
15739 elsif Is_Private_Type (Typ)
15740 and then Present (Full_View (Typ))
15741 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
15745 elsif Is_Generic_Actual_Type (Typ) then
15751 end Comes_From_Generic;
15755 Def : constant Node_Id := Type_Definition (N);
15756 Iface_Def : Node_Id;
15757 Indic : constant Node_Id := Subtype_Indication (Def);
15758 Extension : constant Node_Id := Record_Extension_Part (Def);
15759 Parent_Node : Node_Id;
15762 -- Start of processing for Derived_Type_Declaration
15765 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
15767 -- Ada 2005 (AI-251): In case of interface derivation check that the
15768 -- parent is also an interface.
15770 if Interface_Present (Def) then
15771 Check_SPARK_05_Restriction ("interface is not allowed", Def);
15773 if not Is_Interface (Parent_Type) then
15774 Diagnose_Interface (Indic, Parent_Type);
15777 Parent_Node := Parent (Base_Type (Parent_Type));
15778 Iface_Def := Type_Definition (Parent_Node);
15780 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
15781 -- other limited interfaces.
15783 if Limited_Present (Def) then
15784 if Limited_Present (Iface_Def) then
15787 elsif Protected_Present (Iface_Def) then
15789 ("descendant of& must be declared"
15790 & " as a protected interface",
15793 elsif Synchronized_Present (Iface_Def) then
15795 ("descendant of& must be declared"
15796 & " as a synchronized interface",
15799 elsif Task_Present (Iface_Def) then
15801 ("descendant of& must be declared as a task interface",
15806 ("(Ada 2005) limited interface cannot "
15807 & "inherit from non-limited interface", Indic);
15810 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
15811 -- from non-limited or limited interfaces.
15813 elsif not Protected_Present (Def)
15814 and then not Synchronized_Present (Def)
15815 and then not Task_Present (Def)
15817 if Limited_Present (Iface_Def) then
15820 elsif Protected_Present (Iface_Def) then
15822 ("descendant of& must be declared"
15823 & " as a protected interface",
15826 elsif Synchronized_Present (Iface_Def) then
15828 ("descendant of& must be declared"
15829 & " as a synchronized interface",
15832 elsif Task_Present (Iface_Def) then
15834 ("descendant of& must be declared as a task interface",
15843 if Is_Tagged_Type (Parent_Type)
15844 and then Is_Concurrent_Type (Parent_Type)
15845 and then not Is_Interface (Parent_Type)
15848 ("parent type of a record extension cannot be "
15849 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
15850 Set_Etype (T, Any_Type);
15854 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
15857 if Is_Tagged_Type (Parent_Type)
15858 and then Is_Non_Empty_List (Interface_List (Def))
15865 Intf := First (Interface_List (Def));
15866 while Present (Intf) loop
15867 T := Find_Type_Of_Subtype_Indic (Intf);
15869 if not Is_Interface (T) then
15870 Diagnose_Interface (Intf, T);
15872 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
15873 -- a limited type from having a nonlimited progenitor.
15875 elsif (Limited_Present (Def)
15876 or else (not Is_Interface (Parent_Type)
15877 and then Is_Limited_Type (Parent_Type)))
15878 and then not Is_Limited_Interface (T)
15881 ("progenitor interface& of limited type must be limited",
15890 if Parent_Type = Any_Type
15891 or else Etype (Parent_Type) = Any_Type
15892 or else (Is_Class_Wide_Type (Parent_Type)
15893 and then Etype (Parent_Type) = T)
15895 -- If Parent_Type is undefined or illegal, make new type into a
15896 -- subtype of Any_Type, and set a few attributes to prevent cascaded
15897 -- errors. If this is a self-definition, emit error now.
15899 if T = Parent_Type or else T = Etype (Parent_Type) then
15900 Error_Msg_N ("type cannot be used in its own definition", Indic);
15903 Set_Ekind (T, Ekind (Parent_Type));
15904 Set_Etype (T, Any_Type);
15905 Set_Scalar_Range (T, Scalar_Range (Any_Type));
15907 if Is_Tagged_Type (T)
15908 and then Is_Record_Type (T)
15910 Set_Direct_Primitive_Operations (T, New_Elmt_List);
15916 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
15917 -- an interface is special because the list of interfaces in the full
15918 -- view can be given in any order. For example:
15920 -- type A is interface;
15921 -- type B is interface and A;
15922 -- type D is new B with private;
15924 -- type D is new A and B with null record; -- 1 --
15926 -- In this case we perform the following transformation of -1-:
15928 -- type D is new B and A with null record;
15930 -- If the parent of the full-view covers the parent of the partial-view
15931 -- we have two possible cases:
15933 -- 1) They have the same parent
15934 -- 2) The parent of the full-view implements some further interfaces
15936 -- In both cases we do not need to perform the transformation. In the
15937 -- first case the source program is correct and the transformation is
15938 -- not needed; in the second case the source program does not fulfill
15939 -- the no-hidden interfaces rule (AI-396) and the error will be reported
15942 -- This transformation not only simplifies the rest of the analysis of
15943 -- this type declaration but also simplifies the correct generation of
15944 -- the object layout to the expander.
15946 if In_Private_Part (Current_Scope)
15947 and then Is_Interface (Parent_Type)
15951 Partial_View : Entity_Id;
15952 Partial_View_Parent : Entity_Id;
15953 New_Iface : Node_Id;
15956 -- Look for the associated private type declaration
15958 Partial_View := First_Entity (Current_Scope);
15960 exit when No (Partial_View)
15961 or else (Has_Private_Declaration (Partial_View)
15962 and then Full_View (Partial_View) = T);
15964 Next_Entity (Partial_View);
15967 -- If the partial view was not found then the source code has
15968 -- errors and the transformation is not needed.
15970 if Present (Partial_View) then
15971 Partial_View_Parent := Etype (Partial_View);
15973 -- If the parent of the full-view covers the parent of the
15974 -- partial-view we have nothing else to do.
15976 if Interface_Present_In_Ancestor
15977 (Parent_Type, Partial_View_Parent)
15981 -- Traverse the list of interfaces of the full-view to look
15982 -- for the parent of the partial-view and perform the tree
15986 Iface := First (Interface_List (Def));
15987 while Present (Iface) loop
15988 if Etype (Iface) = Etype (Partial_View) then
15989 Rewrite (Subtype_Indication (Def),
15990 New_Copy (Subtype_Indication
15991 (Parent (Partial_View))));
15994 Make_Identifier (Sloc (N), Chars (Parent_Type));
15995 Append (New_Iface, Interface_List (Def));
15997 -- Analyze the transformed code
15999 Derived_Type_Declaration (T, N, Is_Completion);
16010 -- Only composite types other than array types are allowed to have
16013 if Present (Discriminant_Specifications (N)) then
16014 if (Is_Elementary_Type (Parent_Type)
16016 Is_Array_Type (Parent_Type))
16017 and then not Error_Posted (N)
16020 ("elementary or array type cannot have discriminants",
16021 Defining_Identifier (First (Discriminant_Specifications (N))));
16022 Set_Has_Discriminants (T, False);
16024 -- The type is allowed to have discriminants
16027 Check_SPARK_05_Restriction ("discriminant type is not allowed", N);
16031 -- In Ada 83, a derived type defined in a package specification cannot
16032 -- be used for further derivation until the end of its visible part.
16033 -- Note that derivation in the private part of the package is allowed.
16035 if Ada_Version = Ada_83
16036 and then Is_Derived_Type (Parent_Type)
16037 and then In_Visible_Part (Scope (Parent_Type))
16039 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
16041 ("(Ada 83): premature use of type for derivation", Indic);
16045 -- Check for early use of incomplete or private type
16047 if Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
16048 Error_Msg_N ("premature derivation of incomplete type", Indic);
16051 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
16052 and then not Comes_From_Generic (Parent_Type))
16053 or else Has_Private_Component (Parent_Type)
16055 -- The ancestor type of a formal type can be incomplete, in which
16056 -- case only the operations of the partial view are available in the
16057 -- generic. Subsequent checks may be required when the full view is
16058 -- analyzed to verify that a derivation from a tagged type has an
16061 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
16064 elsif No (Underlying_Type (Parent_Type))
16065 or else Has_Private_Component (Parent_Type)
16068 ("premature derivation of derived or private type", Indic);
16070 -- Flag the type itself as being in error, this prevents some
16071 -- nasty problems with subsequent uses of the malformed type.
16073 Set_Error_Posted (T);
16075 -- Check that within the immediate scope of an untagged partial
16076 -- view it's illegal to derive from the partial view if the
16077 -- full view is tagged. (7.3(7))
16079 -- We verify that the Parent_Type is a partial view by checking
16080 -- that it is not a Full_Type_Declaration (i.e. a private type or
16081 -- private extension declaration), to distinguish a partial view
16082 -- from a derivation from a private type which also appears as
16083 -- E_Private_Type. If the parent base type is not declared in an
16084 -- enclosing scope there is no need to check.
16086 elsif Present (Full_View (Parent_Type))
16087 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
16088 and then not Is_Tagged_Type (Parent_Type)
16089 and then Is_Tagged_Type (Full_View (Parent_Type))
16090 and then In_Open_Scopes (Scope (Base_Type (Parent_Type)))
16093 ("premature derivation from type with tagged full view",
16098 -- Check that form of derivation is appropriate
16100 Taggd := Is_Tagged_Type (Parent_Type);
16102 -- Set the parent type to the class-wide type's specific type in this
16103 -- case to prevent cascading errors
16105 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
16106 Error_Msg_N ("parent type must not be a class-wide type", Indic);
16107 Set_Etype (T, Etype (Parent_Type));
16111 if Present (Extension) and then not Taggd then
16113 ("type derived from untagged type cannot have extension", Indic);
16115 elsif No (Extension) and then Taggd then
16117 -- If this declaration is within a private part (or body) of a
16118 -- generic instantiation then the derivation is allowed (the parent
16119 -- type can only appear tagged in this case if it's a generic actual
16120 -- type, since it would otherwise have been rejected in the analysis
16121 -- of the generic template).
16123 if not Is_Generic_Actual_Type (Parent_Type)
16124 or else In_Visible_Part (Scope (Parent_Type))
16126 if Is_Class_Wide_Type (Parent_Type) then
16128 ("parent type must not be a class-wide type", Indic);
16130 -- Use specific type to prevent cascaded errors.
16132 Parent_Type := Etype (Parent_Type);
16136 ("type derived from tagged type must have extension", Indic);
16141 -- AI-443: Synchronized formal derived types require a private
16142 -- extension. There is no point in checking the ancestor type or
16143 -- the progenitors since the construct is wrong to begin with.
16145 if Ada_Version >= Ada_2005
16146 and then Is_Generic_Type (T)
16147 and then Present (Original_Node (N))
16150 Decl : constant Node_Id := Original_Node (N);
16153 if Nkind (Decl) = N_Formal_Type_Declaration
16154 and then Nkind (Formal_Type_Definition (Decl)) =
16155 N_Formal_Derived_Type_Definition
16156 and then Synchronized_Present (Formal_Type_Definition (Decl))
16157 and then No (Extension)
16159 -- Avoid emitting a duplicate error message
16161 and then not Error_Posted (Indic)
16164 ("synchronized derived type must have extension", N);
16169 if Null_Exclusion_Present (Def)
16170 and then not Is_Access_Type (Parent_Type)
16172 Error_Msg_N ("null exclusion can only apply to an access type", N);
16175 -- Avoid deriving parent primitives of underlying record views
16177 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
16178 Derive_Subps => not Is_Underlying_Record_View (T));
16180 -- AI-419: The parent type of an explicitly limited derived type must
16181 -- be a limited type or a limited interface.
16183 if Limited_Present (Def) then
16184 Set_Is_Limited_Record (T);
16186 if Is_Interface (T) then
16187 Set_Is_Limited_Interface (T);
16190 if not Is_Limited_Type (Parent_Type)
16192 (not Is_Interface (Parent_Type)
16193 or else not Is_Limited_Interface (Parent_Type))
16195 -- AI05-0096: a derivation in the private part of an instance is
16196 -- legal if the generic formal is untagged limited, and the actual
16199 if Is_Generic_Actual_Type (Parent_Type)
16200 and then In_Private_Part (Current_Scope)
16203 (Generic_Parent_Type (Parent (Parent_Type)))
16209 ("parent type& of limited type must be limited",
16215 -- In SPARK, there are no derived type definitions other than type
16216 -- extensions of tagged record types.
16218 if No (Extension) then
16219 Check_SPARK_05_Restriction
16220 ("derived type is not allowed", Original_Node (N));
16222 end Derived_Type_Declaration;
16224 ------------------------
16225 -- Diagnose_Interface --
16226 ------------------------
16228 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
16230 if not Is_Interface (E) and then E /= Any_Type then
16231 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
16233 end Diagnose_Interface;
16235 ----------------------------------
16236 -- Enumeration_Type_Declaration --
16237 ----------------------------------
16239 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
16246 -- Create identifier node representing lower bound
16248 B_Node := New_Node (N_Identifier, Sloc (Def));
16249 L := First (Literals (Def));
16250 Set_Chars (B_Node, Chars (L));
16251 Set_Entity (B_Node, L);
16252 Set_Etype (B_Node, T);
16253 Set_Is_Static_Expression (B_Node, True);
16255 R_Node := New_Node (N_Range, Sloc (Def));
16256 Set_Low_Bound (R_Node, B_Node);
16258 Set_Ekind (T, E_Enumeration_Type);
16259 Set_First_Literal (T, L);
16261 Set_Is_Constrained (T);
16265 -- Loop through literals of enumeration type setting pos and rep values
16266 -- except that if the Ekind is already set, then it means the literal
16267 -- was already constructed (case of a derived type declaration and we
16268 -- should not disturb the Pos and Rep values.
16270 while Present (L) loop
16271 if Ekind (L) /= E_Enumeration_Literal then
16272 Set_Ekind (L, E_Enumeration_Literal);
16273 Set_Enumeration_Pos (L, Ev);
16274 Set_Enumeration_Rep (L, Ev);
16275 Set_Is_Known_Valid (L, True);
16279 New_Overloaded_Entity (L);
16280 Generate_Definition (L);
16281 Set_Convention (L, Convention_Intrinsic);
16283 -- Case of character literal
16285 if Nkind (L) = N_Defining_Character_Literal then
16286 Set_Is_Character_Type (T, True);
16288 -- Check violation of No_Wide_Characters
16290 if Restriction_Check_Required (No_Wide_Characters) then
16291 Get_Name_String (Chars (L));
16293 if Name_Len >= 3 and then Name_Buffer (1 .. 2) = "QW" then
16294 Check_Restriction (No_Wide_Characters, L);
16303 -- Now create a node representing upper bound
16305 B_Node := New_Node (N_Identifier, Sloc (Def));
16306 Set_Chars (B_Node, Chars (Last (Literals (Def))));
16307 Set_Entity (B_Node, Last (Literals (Def)));
16308 Set_Etype (B_Node, T);
16309 Set_Is_Static_Expression (B_Node, True);
16311 Set_High_Bound (R_Node, B_Node);
16313 -- Initialize various fields of the type. Some of this information
16314 -- may be overwritten later through rep.clauses.
16316 Set_Scalar_Range (T, R_Node);
16317 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
16318 Set_Enum_Esize (T);
16319 Set_Enum_Pos_To_Rep (T, Empty);
16321 -- Set Discard_Names if configuration pragma set, or if there is
16322 -- a parameterless pragma in the current declarative region
16324 if Global_Discard_Names or else Discard_Names (Scope (T)) then
16325 Set_Discard_Names (T);
16328 -- Process end label if there is one
16330 if Present (Def) then
16331 Process_End_Label (Def, 'e', T);
16333 end Enumeration_Type_Declaration;
16335 ---------------------------------
16336 -- Expand_To_Stored_Constraint --
16337 ---------------------------------
16339 function Expand_To_Stored_Constraint
16341 Constraint : Elist_Id) return Elist_Id
16343 Explicitly_Discriminated_Type : Entity_Id;
16344 Expansion : Elist_Id;
16345 Discriminant : Entity_Id;
16347 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
16348 -- Find the nearest type that actually specifies discriminants
16350 ---------------------------------
16351 -- Type_With_Explicit_Discrims --
16352 ---------------------------------
16354 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
16355 Typ : constant E := Base_Type (Id);
16358 if Ekind (Typ) in Incomplete_Or_Private_Kind then
16359 if Present (Full_View (Typ)) then
16360 return Type_With_Explicit_Discrims (Full_View (Typ));
16364 if Has_Discriminants (Typ) then
16369 if Etype (Typ) = Typ then
16371 elsif Has_Discriminants (Typ) then
16374 return Type_With_Explicit_Discrims (Etype (Typ));
16377 end Type_With_Explicit_Discrims;
16379 -- Start of processing for Expand_To_Stored_Constraint
16382 if No (Constraint) or else Is_Empty_Elmt_List (Constraint) then
16386 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
16388 if No (Explicitly_Discriminated_Type) then
16392 Expansion := New_Elmt_List;
16395 First_Stored_Discriminant (Explicitly_Discriminated_Type);
16396 while Present (Discriminant) loop
16398 (Get_Discriminant_Value
16399 (Discriminant, Explicitly_Discriminated_Type, Constraint),
16401 Next_Stored_Discriminant (Discriminant);
16405 end Expand_To_Stored_Constraint;
16407 ---------------------------
16408 -- Find_Hidden_Interface --
16409 ---------------------------
16411 function Find_Hidden_Interface
16413 Dest : Elist_Id) return Entity_Id
16416 Iface_Elmt : Elmt_Id;
16419 if Present (Src) and then Present (Dest) then
16420 Iface_Elmt := First_Elmt (Src);
16421 while Present (Iface_Elmt) loop
16422 Iface := Node (Iface_Elmt);
16424 if Is_Interface (Iface)
16425 and then not Contain_Interface (Iface, Dest)
16430 Next_Elmt (Iface_Elmt);
16435 end Find_Hidden_Interface;
16437 --------------------
16438 -- Find_Type_Name --
16439 --------------------
16441 function Find_Type_Name (N : Node_Id) return Entity_Id is
16442 Id : constant Entity_Id := Defining_Identifier (N);
16444 New_Id : Entity_Id;
16445 Prev_Par : Node_Id;
16447 procedure Check_Duplicate_Aspects;
16448 -- Check that aspects specified in a completion have not been specified
16449 -- already in the partial view. Type_Invariant and others can be
16450 -- specified on either view but never on both.
16452 procedure Tag_Mismatch;
16453 -- Diagnose a tagged partial view whose full view is untagged.
16454 -- We post the message on the full view, with a reference to
16455 -- the previous partial view. The partial view can be private
16456 -- or incomplete, and these are handled in a different manner,
16457 -- so we determine the position of the error message from the
16458 -- respective slocs of both.
16460 -----------------------------
16461 -- Check_Duplicate_Aspects --
16462 -----------------------------
16464 procedure Check_Duplicate_Aspects is
16465 Prev_Aspects : constant List_Id := Aspect_Specifications (Prev_Par);
16466 Full_Aspects : constant List_Id := Aspect_Specifications (N);
16467 F_Spec, P_Spec : Node_Id;
16470 if Present (Full_Aspects) then
16471 F_Spec := First (Full_Aspects);
16472 while Present (F_Spec) loop
16473 if Present (Prev_Aspects) then
16474 P_Spec := First (Prev_Aspects);
16475 while Present (P_Spec) loop
16476 if Chars (Identifier (P_Spec)) =
16477 Chars (Identifier (F_Spec))
16480 ("aspect already specified in private declaration",
16490 if Has_Discriminants (Prev)
16491 and then not Has_Unknown_Discriminants (Prev)
16492 and then Chars (Identifier (F_Spec)) =
16493 Name_Implicit_Dereference
16495 Error_Msg_N ("cannot specify aspect " &
16496 "if partial view has known discriminants", F_Spec);
16502 end Check_Duplicate_Aspects;
16508 procedure Tag_Mismatch is
16510 if Sloc (Prev) < Sloc (Id) then
16511 if Ada_Version >= Ada_2012
16512 and then Nkind (N) = N_Private_Type_Declaration
16515 ("declaration of private } must be a tagged type ", Id, Prev);
16518 ("full declaration of } must be a tagged type ", Id, Prev);
16522 if Ada_Version >= Ada_2012
16523 and then Nkind (N) = N_Private_Type_Declaration
16526 ("declaration of private } must be a tagged type ", Prev, Id);
16529 ("full declaration of } must be a tagged type ", Prev, Id);
16534 -- Start of processing for Find_Type_Name
16537 -- Find incomplete declaration, if one was given
16539 Prev := Current_Entity_In_Scope (Id);
16541 -- New type declaration
16547 -- Previous declaration exists
16550 Prev_Par := Parent (Prev);
16552 -- Error if not incomplete/private case except if previous
16553 -- declaration is implicit, etc. Enter_Name will emit error if
16556 if not Is_Incomplete_Or_Private_Type (Prev) then
16560 -- Check invalid completion of private or incomplete type
16562 elsif not Nkind_In (N, N_Full_Type_Declaration,
16563 N_Task_Type_Declaration,
16564 N_Protected_Type_Declaration)
16566 (Ada_Version < Ada_2012
16567 or else not Is_Incomplete_Type (Prev)
16568 or else not Nkind_In (N, N_Private_Type_Declaration,
16569 N_Private_Extension_Declaration))
16571 -- Completion must be a full type declarations (RM 7.3(4))
16573 Error_Msg_Sloc := Sloc (Prev);
16574 Error_Msg_NE ("invalid completion of }", Id, Prev);
16576 -- Set scope of Id to avoid cascaded errors. Entity is never
16577 -- examined again, except when saving globals in generics.
16579 Set_Scope (Id, Current_Scope);
16582 -- If this is a repeated incomplete declaration, no further
16583 -- checks are possible.
16585 if Nkind (N) = N_Incomplete_Type_Declaration then
16589 -- Case of full declaration of incomplete type
16591 elsif Ekind (Prev) = E_Incomplete_Type
16592 and then (Ada_Version < Ada_2012
16593 or else No (Full_View (Prev))
16594 or else not Is_Private_Type (Full_View (Prev)))
16596 -- Indicate that the incomplete declaration has a matching full
16597 -- declaration. The defining occurrence of the incomplete
16598 -- declaration remains the visible one, and the procedure
16599 -- Get_Full_View dereferences it whenever the type is used.
16601 if Present (Full_View (Prev)) then
16602 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
16605 Set_Full_View (Prev, Id);
16606 Append_Entity (Id, Current_Scope);
16607 Set_Is_Public (Id, Is_Public (Prev));
16608 Set_Is_Internal (Id);
16611 -- If the incomplete view is tagged, a class_wide type has been
16612 -- created already. Use it for the private type as well, in order
16613 -- to prevent multiple incompatible class-wide types that may be
16614 -- created for self-referential anonymous access components.
16616 if Is_Tagged_Type (Prev)
16617 and then Present (Class_Wide_Type (Prev))
16619 Set_Ekind (Id, Ekind (Prev)); -- will be reset later
16620 Set_Class_Wide_Type (Id, Class_Wide_Type (Prev));
16622 -- The type of the classwide type is the current Id. Previously
16623 -- this was not done for private declarations because of order-
16624 -- of elaboration issues in the back-end, but gigi now handles
16627 Set_Etype (Class_Wide_Type (Id), Id);
16630 -- Case of full declaration of private type
16633 -- If the private type was a completion of an incomplete type then
16634 -- update Prev to reference the private type
16636 if Ada_Version >= Ada_2012
16637 and then Ekind (Prev) = E_Incomplete_Type
16638 and then Present (Full_View (Prev))
16639 and then Is_Private_Type (Full_View (Prev))
16641 Prev := Full_View (Prev);
16642 Prev_Par := Parent (Prev);
16645 if Nkind (N) = N_Full_Type_Declaration
16647 (Type_Definition (N), N_Record_Definition,
16648 N_Derived_Type_Definition)
16649 and then Interface_Present (Type_Definition (N))
16652 ("completion of private type cannot be an interface", N);
16655 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
16656 if Etype (Prev) /= Prev then
16658 -- Prev is a private subtype or a derived type, and needs
16661 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
16664 elsif Ekind (Prev) = E_Private_Type
16665 and then Nkind_In (N, N_Task_Type_Declaration,
16666 N_Protected_Type_Declaration)
16669 ("completion of nonlimited type cannot be limited", N);
16671 elsif Ekind (Prev) = E_Record_Type_With_Private
16672 and then Nkind_In (N, N_Task_Type_Declaration,
16673 N_Protected_Type_Declaration)
16675 if not Is_Limited_Record (Prev) then
16677 ("completion of nonlimited type cannot be limited", N);
16679 elsif No (Interface_List (N)) then
16681 ("completion of tagged private type must be tagged",
16686 -- Ada 2005 (AI-251): Private extension declaration of a task
16687 -- type or a protected type. This case arises when covering
16688 -- interface types.
16690 elsif Nkind_In (N, N_Task_Type_Declaration,
16691 N_Protected_Type_Declaration)
16695 elsif Nkind (N) /= N_Full_Type_Declaration
16696 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
16699 ("full view of private extension must be an extension", N);
16701 elsif not (Abstract_Present (Parent (Prev)))
16702 and then Abstract_Present (Type_Definition (N))
16705 ("full view of non-abstract extension cannot be abstract", N);
16708 if not In_Private_Part (Current_Scope) then
16710 ("declaration of full view must appear in private part", N);
16713 if Ada_Version >= Ada_2012 then
16714 Check_Duplicate_Aspects;
16717 Copy_And_Swap (Prev, Id);
16718 Set_Has_Private_Declaration (Prev);
16719 Set_Has_Private_Declaration (Id);
16721 -- AI12-0133: Indicate whether we have a partial view with
16722 -- unknown discriminants, in which case initialization of objects
16723 -- of the type do not receive an invariant check.
16725 Set_Partial_View_Has_Unknown_Discr
16726 (Prev, Has_Unknown_Discriminants (Id));
16728 -- Preserve aspect and iterator flags that may have been set on
16729 -- the partial view.
16731 Set_Has_Delayed_Aspects (Prev, Has_Delayed_Aspects (Id));
16732 Set_Has_Implicit_Dereference (Prev, Has_Implicit_Dereference (Id));
16734 -- If no error, propagate freeze_node from private to full view.
16735 -- It may have been generated for an early operational item.
16737 if Present (Freeze_Node (Id))
16738 and then Serious_Errors_Detected = 0
16739 and then No (Full_View (Id))
16741 Set_Freeze_Node (Prev, Freeze_Node (Id));
16742 Set_Freeze_Node (Id, Empty);
16743 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
16746 Set_Full_View (Id, Prev);
16750 -- Verify that full declaration conforms to partial one
16752 if Is_Incomplete_Or_Private_Type (Prev)
16753 and then Present (Discriminant_Specifications (Prev_Par))
16755 if Present (Discriminant_Specifications (N)) then
16756 if Ekind (Prev) = E_Incomplete_Type then
16757 Check_Discriminant_Conformance (N, Prev, Prev);
16759 Check_Discriminant_Conformance (N, Prev, Id);
16764 ("missing discriminants in full type declaration", N);
16766 -- To avoid cascaded errors on subsequent use, share the
16767 -- discriminants of the partial view.
16769 Set_Discriminant_Specifications (N,
16770 Discriminant_Specifications (Prev_Par));
16774 -- A prior untagged partial view can have an associated class-wide
16775 -- type due to use of the class attribute, and in this case the full
16776 -- type must also be tagged. This Ada 95 usage is deprecated in favor
16777 -- of incomplete tagged declarations, but we check for it.
16780 and then (Is_Tagged_Type (Prev)
16781 or else Present (Class_Wide_Type (Prev)))
16783 -- Ada 2012 (AI05-0162): A private type may be the completion of
16784 -- an incomplete type.
16786 if Ada_Version >= Ada_2012
16787 and then Is_Incomplete_Type (Prev)
16788 and then Nkind_In (N, N_Private_Type_Declaration,
16789 N_Private_Extension_Declaration)
16791 -- No need to check private extensions since they are tagged
16793 if Nkind (N) = N_Private_Type_Declaration
16794 and then not Tagged_Present (N)
16799 -- The full declaration is either a tagged type (including
16800 -- a synchronized type that implements interfaces) or a
16801 -- type extension, otherwise this is an error.
16803 elsif Nkind_In (N, N_Task_Type_Declaration,
16804 N_Protected_Type_Declaration)
16806 if No (Interface_List (N)) and then not Error_Posted (N) then
16810 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
16812 -- Indicate that the previous declaration (tagged incomplete
16813 -- or private declaration) requires the same on the full one.
16815 if not Tagged_Present (Type_Definition (N)) then
16817 Set_Is_Tagged_Type (Id);
16820 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
16821 if No (Record_Extension_Part (Type_Definition (N))) then
16823 ("full declaration of } must be a record extension",
16826 -- Set some attributes to produce a usable full view
16828 Set_Is_Tagged_Type (Id);
16837 and then Nkind (Parent (Prev)) = N_Incomplete_Type_Declaration
16838 and then Present (Premature_Use (Parent (Prev)))
16840 Error_Msg_Sloc := Sloc (N);
16842 ("\full declaration #", Premature_Use (Parent (Prev)));
16847 end Find_Type_Name;
16849 -------------------------
16850 -- Find_Type_Of_Object --
16851 -------------------------
16853 function Find_Type_Of_Object
16854 (Obj_Def : Node_Id;
16855 Related_Nod : Node_Id) return Entity_Id
16857 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
16858 P : Node_Id := Parent (Obj_Def);
16863 -- If the parent is a component_definition node we climb to the
16864 -- component_declaration node
16866 if Nkind (P) = N_Component_Definition then
16870 -- Case of an anonymous array subtype
16872 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
16873 N_Unconstrained_Array_Definition)
16876 Array_Type_Declaration (T, Obj_Def);
16878 -- Create an explicit subtype whenever possible
16880 elsif Nkind (P) /= N_Component_Declaration
16881 and then Def_Kind = N_Subtype_Indication
16883 -- Base name of subtype on object name, which will be unique in
16884 -- the current scope.
16886 -- If this is a duplicate declaration, return base type, to avoid
16887 -- generating duplicate anonymous types.
16889 if Error_Posted (P) then
16890 Analyze (Subtype_Mark (Obj_Def));
16891 return Entity (Subtype_Mark (Obj_Def));
16896 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
16898 T := Make_Defining_Identifier (Sloc (P), Nam);
16900 Insert_Action (Obj_Def,
16901 Make_Subtype_Declaration (Sloc (P),
16902 Defining_Identifier => T,
16903 Subtype_Indication => Relocate_Node (Obj_Def)));
16905 -- This subtype may need freezing, and this will not be done
16906 -- automatically if the object declaration is not in declarative
16907 -- part. Since this is an object declaration, the type cannot always
16908 -- be frozen here. Deferred constants do not freeze their type
16909 -- (which often enough will be private).
16911 if Nkind (P) = N_Object_Declaration
16912 and then Constant_Present (P)
16913 and then No (Expression (P))
16917 -- Here we freeze the base type of object type to catch premature use
16918 -- of discriminated private type without a full view.
16921 Insert_Actions (Obj_Def, Freeze_Entity (Base_Type (T), P));
16924 -- Ada 2005 AI-406: the object definition in an object declaration
16925 -- can be an access definition.
16927 elsif Def_Kind = N_Access_Definition then
16928 T := Access_Definition (Related_Nod, Obj_Def);
16930 Set_Is_Local_Anonymous_Access
16932 V => (Ada_Version < Ada_2012)
16933 or else (Nkind (P) /= N_Object_Declaration)
16934 or else Is_Library_Level_Entity (Defining_Identifier (P)));
16936 -- Otherwise, the object definition is just a subtype_mark
16939 T := Process_Subtype (Obj_Def, Related_Nod);
16941 -- If expansion is disabled an object definition that is an aggregate
16942 -- will not get expanded and may lead to scoping problems in the back
16943 -- end, if the object is referenced in an inner scope. In that case
16944 -- create an itype reference for the object definition now. This
16945 -- may be redundant in some cases, but harmless.
16948 and then Nkind (Related_Nod) = N_Object_Declaration
16951 Build_Itype_Reference (T, Related_Nod);
16956 end Find_Type_Of_Object;
16958 --------------------------------
16959 -- Find_Type_Of_Subtype_Indic --
16960 --------------------------------
16962 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
16966 -- Case of subtype mark with a constraint
16968 if Nkind (S) = N_Subtype_Indication then
16969 Find_Type (Subtype_Mark (S));
16970 Typ := Entity (Subtype_Mark (S));
16973 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
16976 ("incorrect constraint for this kind of type", Constraint (S));
16977 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
16980 -- Otherwise we have a subtype mark without a constraint
16982 elsif Error_Posted (S) then
16983 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
16991 -- Check No_Wide_Characters restriction
16993 Check_Wide_Character_Restriction (Typ, S);
16996 end Find_Type_Of_Subtype_Indic;
16998 -------------------------------------
16999 -- Floating_Point_Type_Declaration --
17000 -------------------------------------
17002 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
17003 Digs : constant Node_Id := Digits_Expression (Def);
17004 Max_Digs_Val : constant Uint := Digits_Value (Standard_Long_Long_Float);
17006 Base_Typ : Entity_Id;
17007 Implicit_Base : Entity_Id;
17010 function Can_Derive_From (E : Entity_Id) return Boolean;
17011 -- Find if given digits value, and possibly a specified range, allows
17012 -- derivation from specified type
17014 function Find_Base_Type return Entity_Id;
17015 -- Find a predefined base type that Def can derive from, or generate
17016 -- an error and substitute Long_Long_Float if none exists.
17018 ---------------------
17019 -- Can_Derive_From --
17020 ---------------------
17022 function Can_Derive_From (E : Entity_Id) return Boolean is
17023 Spec : constant Entity_Id := Real_Range_Specification (Def);
17026 -- Check specified "digits" constraint
17028 if Digs_Val > Digits_Value (E) then
17032 -- Check for matching range, if specified
17034 if Present (Spec) then
17035 if Expr_Value_R (Type_Low_Bound (E)) >
17036 Expr_Value_R (Low_Bound (Spec))
17041 if Expr_Value_R (Type_High_Bound (E)) <
17042 Expr_Value_R (High_Bound (Spec))
17049 end Can_Derive_From;
17051 --------------------
17052 -- Find_Base_Type --
17053 --------------------
17055 function Find_Base_Type return Entity_Id is
17056 Choice : Elmt_Id := First_Elmt (Predefined_Float_Types);
17059 -- Iterate over the predefined types in order, returning the first
17060 -- one that Def can derive from.
17062 while Present (Choice) loop
17063 if Can_Derive_From (Node (Choice)) then
17064 return Node (Choice);
17067 Next_Elmt (Choice);
17070 -- If we can't derive from any existing type, use Long_Long_Float
17071 -- and give appropriate message explaining the problem.
17073 if Digs_Val > Max_Digs_Val then
17074 -- It might be the case that there is a type with the requested
17075 -- range, just not the combination of digits and range.
17078 ("no predefined type has requested range and precision",
17079 Real_Range_Specification (Def));
17083 ("range too large for any predefined type",
17084 Real_Range_Specification (Def));
17087 return Standard_Long_Long_Float;
17088 end Find_Base_Type;
17090 -- Start of processing for Floating_Point_Type_Declaration
17093 Check_Restriction (No_Floating_Point, Def);
17095 -- Create an implicit base type
17098 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
17100 -- Analyze and verify digits value
17102 Analyze_And_Resolve (Digs, Any_Integer);
17103 Check_Digits_Expression (Digs);
17104 Digs_Val := Expr_Value (Digs);
17106 -- Process possible range spec and find correct type to derive from
17108 Process_Real_Range_Specification (Def);
17110 -- Check that requested number of digits is not too high.
17112 if Digs_Val > Max_Digs_Val then
17114 -- The check for Max_Base_Digits may be somewhat expensive, as it
17115 -- requires reading System, so only do it when necessary.
17118 Max_Base_Digits : constant Uint :=
17121 (Parent (RTE (RE_Max_Base_Digits))));
17124 if Digs_Val > Max_Base_Digits then
17125 Error_Msg_Uint_1 := Max_Base_Digits;
17126 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
17128 elsif No (Real_Range_Specification (Def)) then
17129 Error_Msg_Uint_1 := Max_Digs_Val;
17130 Error_Msg_N ("types with more than ^ digits need range spec "
17131 & "(RM 3.5.7(6))", Digs);
17136 -- Find a suitable type to derive from or complain and use a substitute
17138 Base_Typ := Find_Base_Type;
17140 -- If there are bounds given in the declaration use them as the bounds
17141 -- of the type, otherwise use the bounds of the predefined base type
17142 -- that was chosen based on the Digits value.
17144 if Present (Real_Range_Specification (Def)) then
17145 Set_Scalar_Range (T, Real_Range_Specification (Def));
17146 Set_Is_Constrained (T);
17148 -- The bounds of this range must be converted to machine numbers
17149 -- in accordance with RM 4.9(38).
17151 Bound := Type_Low_Bound (T);
17153 if Nkind (Bound) = N_Real_Literal then
17155 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
17156 Set_Is_Machine_Number (Bound);
17159 Bound := Type_High_Bound (T);
17161 if Nkind (Bound) = N_Real_Literal then
17163 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
17164 Set_Is_Machine_Number (Bound);
17168 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
17171 -- Complete definition of implicit base and declared first subtype. The
17172 -- inheritance of the rep item chain ensures that SPARK-related pragmas
17173 -- are not clobbered when the floating point type acts as a full view of
17176 Set_Etype (Implicit_Base, Base_Typ);
17177 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
17178 Set_Size_Info (Implicit_Base, Base_Typ);
17179 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
17180 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
17181 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
17182 Set_Float_Rep (Implicit_Base, Float_Rep (Base_Typ));
17184 Set_Ekind (T, E_Floating_Point_Subtype);
17185 Set_Etype (T, Implicit_Base);
17186 Set_Size_Info (T, Implicit_Base);
17187 Set_RM_Size (T, RM_Size (Implicit_Base));
17188 Inherit_Rep_Item_Chain (T, Implicit_Base);
17189 Set_Digits_Value (T, Digs_Val);
17190 end Floating_Point_Type_Declaration;
17192 ----------------------------
17193 -- Get_Discriminant_Value --
17194 ----------------------------
17196 -- This is the situation:
17198 -- There is a non-derived type
17200 -- type T0 (Dx, Dy, Dz...)
17202 -- There are zero or more levels of derivation, with each derivation
17203 -- either purely inheriting the discriminants, or defining its own.
17205 -- type Ti is new Ti-1
17207 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
17209 -- subtype Ti is ...
17211 -- The subtype issue is avoided by the use of Original_Record_Component,
17212 -- and the fact that derived subtypes also derive the constraints.
17214 -- This chain leads back from
17216 -- Typ_For_Constraint
17218 -- Typ_For_Constraint has discriminants, and the value for each
17219 -- discriminant is given by its corresponding Elmt of Constraints.
17221 -- Discriminant is some discriminant in this hierarchy
17223 -- We need to return its value
17225 -- We do this by recursively searching each level, and looking for
17226 -- Discriminant. Once we get to the bottom, we start backing up
17227 -- returning the value for it which may in turn be a discriminant
17228 -- further up, so on the backup we continue the substitution.
17230 function Get_Discriminant_Value
17231 (Discriminant : Entity_Id;
17232 Typ_For_Constraint : Entity_Id;
17233 Constraint : Elist_Id) return Node_Id
17235 function Root_Corresponding_Discriminant
17236 (Discr : Entity_Id) return Entity_Id;
17237 -- Given a discriminant, traverse the chain of inherited discriminants
17238 -- and return the topmost discriminant.
17240 function Search_Derivation_Levels
17242 Discrim_Values : Elist_Id;
17243 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
17244 -- This is the routine that performs the recursive search of levels
17245 -- as described above.
17247 -------------------------------------
17248 -- Root_Corresponding_Discriminant --
17249 -------------------------------------
17251 function Root_Corresponding_Discriminant
17252 (Discr : Entity_Id) return Entity_Id
17258 while Present (Corresponding_Discriminant (D)) loop
17259 D := Corresponding_Discriminant (D);
17263 end Root_Corresponding_Discriminant;
17265 ------------------------------
17266 -- Search_Derivation_Levels --
17267 ------------------------------
17269 function Search_Derivation_Levels
17271 Discrim_Values : Elist_Id;
17272 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
17276 Result : Node_Or_Entity_Id;
17277 Result_Entity : Node_Id;
17280 -- If inappropriate type, return Error, this happens only in
17281 -- cascaded error situations, and we want to avoid a blow up.
17283 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
17287 -- Look deeper if possible. Use Stored_Constraints only for
17288 -- untagged types. For tagged types use the given constraint.
17289 -- This asymmetry needs explanation???
17291 if not Stored_Discrim_Values
17292 and then Present (Stored_Constraint (Ti))
17293 and then not Is_Tagged_Type (Ti)
17296 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
17299 Td : constant Entity_Id := Etype (Ti);
17303 Result := Discriminant;
17306 if Present (Stored_Constraint (Ti)) then
17308 Search_Derivation_Levels
17309 (Td, Stored_Constraint (Ti), True);
17312 Search_Derivation_Levels
17313 (Td, Discrim_Values, Stored_Discrim_Values);
17319 -- Extra underlying places to search, if not found above. For
17320 -- concurrent types, the relevant discriminant appears in the
17321 -- corresponding record. For a type derived from a private type
17322 -- without discriminant, the full view inherits the discriminants
17323 -- of the full view of the parent.
17325 if Result = Discriminant then
17326 if Is_Concurrent_Type (Ti)
17327 and then Present (Corresponding_Record_Type (Ti))
17330 Search_Derivation_Levels (
17331 Corresponding_Record_Type (Ti),
17333 Stored_Discrim_Values);
17335 elsif Is_Private_Type (Ti)
17336 and then not Has_Discriminants (Ti)
17337 and then Present (Full_View (Ti))
17338 and then Etype (Full_View (Ti)) /= Ti
17341 Search_Derivation_Levels (
17344 Stored_Discrim_Values);
17348 -- If Result is not a (reference to a) discriminant, return it,
17349 -- otherwise set Result_Entity to the discriminant.
17351 if Nkind (Result) = N_Defining_Identifier then
17352 pragma Assert (Result = Discriminant);
17353 Result_Entity := Result;
17356 if not Denotes_Discriminant (Result) then
17360 Result_Entity := Entity (Result);
17363 -- See if this level of derivation actually has discriminants because
17364 -- tagged derivations can add them, hence the lower levels need not
17367 if not Has_Discriminants (Ti) then
17371 -- Scan Ti's discriminants for Result_Entity, and return its
17372 -- corresponding value, if any.
17374 Result_Entity := Original_Record_Component (Result_Entity);
17376 Assoc := First_Elmt (Discrim_Values);
17378 if Stored_Discrim_Values then
17379 Disc := First_Stored_Discriminant (Ti);
17381 Disc := First_Discriminant (Ti);
17384 while Present (Disc) loop
17385 pragma Assert (Present (Assoc));
17387 if Original_Record_Component (Disc) = Result_Entity then
17388 return Node (Assoc);
17393 if Stored_Discrim_Values then
17394 Next_Stored_Discriminant (Disc);
17396 Next_Discriminant (Disc);
17400 -- Could not find it
17403 end Search_Derivation_Levels;
17407 Result : Node_Or_Entity_Id;
17409 -- Start of processing for Get_Discriminant_Value
17412 -- ??? This routine is a gigantic mess and will be deleted. For the
17413 -- time being just test for the trivial case before calling recurse.
17415 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
17421 D := First_Discriminant (Typ_For_Constraint);
17422 E := First_Elmt (Constraint);
17423 while Present (D) loop
17424 if Chars (D) = Chars (Discriminant) then
17428 Next_Discriminant (D);
17434 Result := Search_Derivation_Levels
17435 (Typ_For_Constraint, Constraint, False);
17437 -- ??? hack to disappear when this routine is gone
17439 if Nkind (Result) = N_Defining_Identifier then
17445 D := First_Discriminant (Typ_For_Constraint);
17446 E := First_Elmt (Constraint);
17447 while Present (D) loop
17448 if Root_Corresponding_Discriminant (D) = Discriminant then
17452 Next_Discriminant (D);
17458 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
17460 end Get_Discriminant_Value;
17462 --------------------------
17463 -- Has_Range_Constraint --
17464 --------------------------
17466 function Has_Range_Constraint (N : Node_Id) return Boolean is
17467 C : constant Node_Id := Constraint (N);
17470 if Nkind (C) = N_Range_Constraint then
17473 elsif Nkind (C) = N_Digits_Constraint then
17475 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
17476 or else Present (Range_Constraint (C));
17478 elsif Nkind (C) = N_Delta_Constraint then
17479 return Present (Range_Constraint (C));
17484 end Has_Range_Constraint;
17486 ------------------------
17487 -- Inherit_Components --
17488 ------------------------
17490 function Inherit_Components
17492 Parent_Base : Entity_Id;
17493 Derived_Base : Entity_Id;
17494 Is_Tagged : Boolean;
17495 Inherit_Discr : Boolean;
17496 Discs : Elist_Id) return Elist_Id
17498 Assoc_List : constant Elist_Id := New_Elmt_List;
17500 procedure Inherit_Component
17501 (Old_C : Entity_Id;
17502 Plain_Discrim : Boolean := False;
17503 Stored_Discrim : Boolean := False);
17504 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
17505 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
17506 -- True, Old_C is a stored discriminant. If they are both false then
17507 -- Old_C is a regular component.
17509 -----------------------
17510 -- Inherit_Component --
17511 -----------------------
17513 procedure Inherit_Component
17514 (Old_C : Entity_Id;
17515 Plain_Discrim : Boolean := False;
17516 Stored_Discrim : Boolean := False)
17518 procedure Set_Anonymous_Type (Id : Entity_Id);
17519 -- Id denotes the entity of an access discriminant or anonymous
17520 -- access component. Set the type of Id to either the same type of
17521 -- Old_C or create a new one depending on whether the parent and
17522 -- the child types are in the same scope.
17524 ------------------------
17525 -- Set_Anonymous_Type --
17526 ------------------------
17528 procedure Set_Anonymous_Type (Id : Entity_Id) is
17529 Old_Typ : constant Entity_Id := Etype (Old_C);
17532 if Scope (Parent_Base) = Scope (Derived_Base) then
17533 Set_Etype (Id, Old_Typ);
17535 -- The parent and the derived type are in two different scopes.
17536 -- Reuse the type of the original discriminant / component by
17537 -- copying it in order to preserve all attributes.
17541 Typ : constant Entity_Id := New_Copy (Old_Typ);
17544 Set_Etype (Id, Typ);
17546 -- Since we do not generate component declarations for
17547 -- inherited components, associate the itype with the
17550 Set_Associated_Node_For_Itype (Typ, Parent (Derived_Base));
17551 Set_Scope (Typ, Derived_Base);
17554 end Set_Anonymous_Type;
17556 -- Local variables and constants
17558 New_C : constant Entity_Id := New_Copy (Old_C);
17560 Corr_Discrim : Entity_Id;
17561 Discrim : Entity_Id;
17563 -- Start of processing for Inherit_Component
17566 pragma Assert (not Is_Tagged or not Stored_Discrim);
17568 Set_Parent (New_C, Parent (Old_C));
17570 -- Regular discriminants and components must be inserted in the scope
17571 -- of the Derived_Base. Do it here.
17573 if not Stored_Discrim then
17574 Enter_Name (New_C);
17577 -- For tagged types the Original_Record_Component must point to
17578 -- whatever this field was pointing to in the parent type. This has
17579 -- already been achieved by the call to New_Copy above.
17581 if not Is_Tagged then
17582 Set_Original_Record_Component (New_C, New_C);
17585 -- Set the proper type of an access discriminant
17587 if Ekind (New_C) = E_Discriminant
17588 and then Ekind (Etype (New_C)) = E_Anonymous_Access_Type
17590 Set_Anonymous_Type (New_C);
17593 -- If we have inherited a component then see if its Etype contains
17594 -- references to Parent_Base discriminants. In this case, replace
17595 -- these references with the constraints given in Discs. We do not
17596 -- do this for the partial view of private types because this is
17597 -- not needed (only the components of the full view will be used
17598 -- for code generation) and cause problem. We also avoid this
17599 -- transformation in some error situations.
17601 if Ekind (New_C) = E_Component then
17603 -- Set the proper type of an anonymous access component
17605 if Ekind (Etype (New_C)) = E_Anonymous_Access_Type then
17606 Set_Anonymous_Type (New_C);
17608 elsif (Is_Private_Type (Derived_Base)
17609 and then not Is_Generic_Type (Derived_Base))
17610 or else (Is_Empty_Elmt_List (Discs)
17611 and then not Expander_Active)
17613 Set_Etype (New_C, Etype (Old_C));
17616 -- The current component introduces a circularity of the
17619 -- limited with Pack_2;
17620 -- package Pack_1 is
17621 -- type T_1 is tagged record
17622 -- Comp : access Pack_2.T_2;
17628 -- package Pack_2 is
17629 -- type T_2 is new Pack_1.T_1 with ...;
17634 Constrain_Component_Type
17635 (Old_C, Derived_Base, N, Parent_Base, Discs));
17639 -- In derived tagged types it is illegal to reference a non
17640 -- discriminant component in the parent type. To catch this, mark
17641 -- these components with an Ekind of E_Void. This will be reset in
17642 -- Record_Type_Definition after processing the record extension of
17643 -- the derived type.
17645 -- If the declaration is a private extension, there is no further
17646 -- record extension to process, and the components retain their
17647 -- current kind, because they are visible at this point.
17649 if Is_Tagged and then Ekind (New_C) = E_Component
17650 and then Nkind (N) /= N_Private_Extension_Declaration
17652 Set_Ekind (New_C, E_Void);
17655 if Plain_Discrim then
17656 Set_Corresponding_Discriminant (New_C, Old_C);
17657 Build_Discriminal (New_C);
17659 -- If we are explicitly inheriting a stored discriminant it will be
17660 -- completely hidden.
17662 elsif Stored_Discrim then
17663 Set_Corresponding_Discriminant (New_C, Empty);
17664 Set_Discriminal (New_C, Empty);
17665 Set_Is_Completely_Hidden (New_C);
17667 -- Set the Original_Record_Component of each discriminant in the
17668 -- derived base to point to the corresponding stored that we just
17671 Discrim := First_Discriminant (Derived_Base);
17672 while Present (Discrim) loop
17673 Corr_Discrim := Corresponding_Discriminant (Discrim);
17675 -- Corr_Discrim could be missing in an error situation
17677 if Present (Corr_Discrim)
17678 and then Original_Record_Component (Corr_Discrim) = Old_C
17680 Set_Original_Record_Component (Discrim, New_C);
17683 Next_Discriminant (Discrim);
17686 Append_Entity (New_C, Derived_Base);
17689 if not Is_Tagged then
17690 Append_Elmt (Old_C, Assoc_List);
17691 Append_Elmt (New_C, Assoc_List);
17693 end Inherit_Component;
17695 -- Variables local to Inherit_Component
17697 Loc : constant Source_Ptr := Sloc (N);
17699 Parent_Discrim : Entity_Id;
17700 Stored_Discrim : Entity_Id;
17702 Component : Entity_Id;
17704 -- Start of processing for Inherit_Components
17707 if not Is_Tagged then
17708 Append_Elmt (Parent_Base, Assoc_List);
17709 Append_Elmt (Derived_Base, Assoc_List);
17712 -- Inherit parent discriminants if needed
17714 if Inherit_Discr then
17715 Parent_Discrim := First_Discriminant (Parent_Base);
17716 while Present (Parent_Discrim) loop
17717 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
17718 Next_Discriminant (Parent_Discrim);
17722 -- Create explicit stored discrims for untagged types when necessary
17724 if not Has_Unknown_Discriminants (Derived_Base)
17725 and then Has_Discriminants (Parent_Base)
17726 and then not Is_Tagged
17729 or else First_Discriminant (Parent_Base) /=
17730 First_Stored_Discriminant (Parent_Base))
17732 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
17733 while Present (Stored_Discrim) loop
17734 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
17735 Next_Stored_Discriminant (Stored_Discrim);
17739 -- See if we can apply the second transformation for derived types, as
17740 -- explained in point 6. in the comments above Build_Derived_Record_Type
17741 -- This is achieved by appending Derived_Base discriminants into Discs,
17742 -- which has the side effect of returning a non empty Discs list to the
17743 -- caller of Inherit_Components, which is what we want. This must be
17744 -- done for private derived types if there are explicit stored
17745 -- discriminants, to ensure that we can retrieve the values of the
17746 -- constraints provided in the ancestors.
17749 and then Is_Empty_Elmt_List (Discs)
17750 and then Present (First_Discriminant (Derived_Base))
17752 (not Is_Private_Type (Derived_Base)
17753 or else Is_Completely_Hidden
17754 (First_Stored_Discriminant (Derived_Base))
17755 or else Is_Generic_Type (Derived_Base))
17757 D := First_Discriminant (Derived_Base);
17758 while Present (D) loop
17759 Append_Elmt (New_Occurrence_Of (D, Loc), Discs);
17760 Next_Discriminant (D);
17764 -- Finally, inherit non-discriminant components unless they are not
17765 -- visible because defined or inherited from the full view of the
17766 -- parent. Don't inherit the _parent field of the parent type.
17768 Component := First_Entity (Parent_Base);
17769 while Present (Component) loop
17771 -- Ada 2005 (AI-251): Do not inherit components associated with
17772 -- secondary tags of the parent.
17774 if Ekind (Component) = E_Component
17775 and then Present (Related_Type (Component))
17779 elsif Ekind (Component) /= E_Component
17780 or else Chars (Component) = Name_uParent
17784 -- If the derived type is within the parent type's declarative
17785 -- region, then the components can still be inherited even though
17786 -- they aren't visible at this point. This can occur for cases
17787 -- such as within public child units where the components must
17788 -- become visible upon entering the child unit's private part.
17790 elsif not Is_Visible_Component (Component)
17791 and then not In_Open_Scopes (Scope (Parent_Base))
17795 elsif Ekind_In (Derived_Base, E_Private_Type,
17796 E_Limited_Private_Type)
17801 Inherit_Component (Component);
17804 Next_Entity (Component);
17807 -- For tagged derived types, inherited discriminants cannot be used in
17808 -- component declarations of the record extension part. To achieve this
17809 -- we mark the inherited discriminants as not visible.
17811 if Is_Tagged and then Inherit_Discr then
17812 D := First_Discriminant (Derived_Base);
17813 while Present (D) loop
17814 Set_Is_Immediately_Visible (D, False);
17815 Next_Discriminant (D);
17820 end Inherit_Components;
17822 -----------------------------
17823 -- Inherit_Predicate_Flags --
17824 -----------------------------
17826 procedure Inherit_Predicate_Flags (Subt, Par : Entity_Id) is
17828 Set_Has_Predicates (Subt, Has_Predicates (Par));
17829 Set_Has_Static_Predicate_Aspect
17830 (Subt, Has_Static_Predicate_Aspect (Par));
17831 Set_Has_Dynamic_Predicate_Aspect
17832 (Subt, Has_Dynamic_Predicate_Aspect (Par));
17833 end Inherit_Predicate_Flags;
17835 ----------------------
17836 -- Is_EVF_Procedure --
17837 ----------------------
17839 function Is_EVF_Procedure (Subp : Entity_Id) return Boolean is
17840 Formal : Entity_Id;
17843 -- Examine the formals of an Extensions_Visible False procedure looking
17844 -- for a controlling OUT parameter.
17846 if Ekind (Subp) = E_Procedure
17847 and then Extensions_Visible_Status (Subp) = Extensions_Visible_False
17849 Formal := First_Formal (Subp);
17850 while Present (Formal) loop
17851 if Ekind (Formal) = E_Out_Parameter
17852 and then Is_Controlling_Formal (Formal)
17857 Next_Formal (Formal);
17862 end Is_EVF_Procedure;
17864 -----------------------
17865 -- Is_Null_Extension --
17866 -----------------------
17868 function Is_Null_Extension (T : Entity_Id) return Boolean is
17869 Type_Decl : constant Node_Id := Parent (Base_Type (T));
17870 Comp_List : Node_Id;
17874 if Nkind (Type_Decl) /= N_Full_Type_Declaration
17875 or else not Is_Tagged_Type (T)
17876 or else Nkind (Type_Definition (Type_Decl)) /=
17877 N_Derived_Type_Definition
17878 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
17884 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
17886 if Present (Discriminant_Specifications (Type_Decl)) then
17889 elsif Present (Comp_List)
17890 and then Is_Non_Empty_List (Component_Items (Comp_List))
17892 Comp := First (Component_Items (Comp_List));
17894 -- Only user-defined components are relevant. The component list
17895 -- may also contain a parent component and internal components
17896 -- corresponding to secondary tags, but these do not determine
17897 -- whether this is a null extension.
17899 while Present (Comp) loop
17900 if Comes_From_Source (Comp) then
17912 end Is_Null_Extension;
17914 ------------------------------
17915 -- Is_Valid_Constraint_Kind --
17916 ------------------------------
17918 function Is_Valid_Constraint_Kind
17919 (T_Kind : Type_Kind;
17920 Constraint_Kind : Node_Kind) return Boolean
17924 when Enumeration_Kind |
17926 return Constraint_Kind = N_Range_Constraint;
17928 when Decimal_Fixed_Point_Kind =>
17929 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
17930 N_Range_Constraint);
17932 when Ordinary_Fixed_Point_Kind =>
17933 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
17934 N_Range_Constraint);
17937 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
17938 N_Range_Constraint);
17945 E_Incomplete_Type |
17948 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
17951 return True; -- Error will be detected later
17953 end Is_Valid_Constraint_Kind;
17955 --------------------------
17956 -- Is_Visible_Component --
17957 --------------------------
17959 function Is_Visible_Component
17961 N : Node_Id := Empty) return Boolean
17963 Original_Comp : Entity_Id := Empty;
17964 Original_Type : Entity_Id;
17965 Type_Scope : Entity_Id;
17967 function Is_Local_Type (Typ : Entity_Id) return Boolean;
17968 -- Check whether parent type of inherited component is declared locally,
17969 -- possibly within a nested package or instance. The current scope is
17970 -- the derived record itself.
17972 -------------------
17973 -- Is_Local_Type --
17974 -------------------
17976 function Is_Local_Type (Typ : Entity_Id) return Boolean is
17980 Scop := Scope (Typ);
17981 while Present (Scop)
17982 and then Scop /= Standard_Standard
17984 if Scop = Scope (Current_Scope) then
17988 Scop := Scope (Scop);
17994 -- Start of processing for Is_Visible_Component
17997 if Ekind_In (C, E_Component, E_Discriminant) then
17998 Original_Comp := Original_Record_Component (C);
18001 if No (Original_Comp) then
18003 -- Premature usage, or previous error
18008 Original_Type := Scope (Original_Comp);
18009 Type_Scope := Scope (Base_Type (Scope (C)));
18012 -- This test only concerns tagged types
18014 if not Is_Tagged_Type (Original_Type) then
18017 -- If it is _Parent or _Tag, there is no visibility issue
18019 elsif not Comes_From_Source (Original_Comp) then
18022 -- Discriminants are visible unless the (private) type has unknown
18023 -- discriminants. If the discriminant reference is inserted for a
18024 -- discriminant check on a full view it is also visible.
18026 elsif Ekind (Original_Comp) = E_Discriminant
18028 (not Has_Unknown_Discriminants (Original_Type)
18029 or else (Present (N)
18030 and then Nkind (N) = N_Selected_Component
18031 and then Nkind (Prefix (N)) = N_Type_Conversion
18032 and then not Comes_From_Source (Prefix (N))))
18036 -- In the body of an instantiation, no need to check for the visibility
18039 elsif In_Instance_Body then
18042 -- If the component has been declared in an ancestor which is currently
18043 -- a private type, then it is not visible. The same applies if the
18044 -- component's containing type is not in an open scope and the original
18045 -- component's enclosing type is a visible full view of a private type
18046 -- (which can occur in cases where an attempt is being made to reference
18047 -- a component in a sibling package that is inherited from a visible
18048 -- component of a type in an ancestor package; the component in the
18049 -- sibling package should not be visible even though the component it
18050 -- inherited from is visible). This does not apply however in the case
18051 -- where the scope of the type is a private child unit, or when the
18052 -- parent comes from a local package in which the ancestor is currently
18053 -- visible. The latter suppression of visibility is needed for cases
18054 -- that are tested in B730006.
18056 elsif Is_Private_Type (Original_Type)
18058 (not Is_Private_Descendant (Type_Scope)
18059 and then not In_Open_Scopes (Type_Scope)
18060 and then Has_Private_Declaration (Original_Type))
18062 -- If the type derives from an entity in a formal package, there
18063 -- are no additional visible components.
18065 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
18066 N_Formal_Package_Declaration
18070 -- if we are not in the private part of the current package, there
18071 -- are no additional visible components.
18073 elsif Ekind (Scope (Current_Scope)) = E_Package
18074 and then not In_Private_Part (Scope (Current_Scope))
18079 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
18080 and then In_Open_Scopes (Scope (Original_Type))
18081 and then Is_Local_Type (Type_Scope);
18084 -- There is another weird way in which a component may be invisible when
18085 -- the private and the full view are not derived from the same ancestor.
18086 -- Here is an example :
18088 -- type A1 is tagged record F1 : integer; end record;
18089 -- type A2 is new A1 with record F2 : integer; end record;
18090 -- type T is new A1 with private;
18092 -- type T is new A2 with null record;
18094 -- In this case, the full view of T inherits F1 and F2 but the private
18095 -- view inherits only F1
18099 Ancestor : Entity_Id := Scope (C);
18103 if Ancestor = Original_Type then
18106 -- The ancestor may have a partial view of the original type,
18107 -- but if the full view is in scope, as in a child body, the
18108 -- component is visible.
18110 elsif In_Private_Part (Scope (Original_Type))
18111 and then Full_View (Ancestor) = Original_Type
18115 elsif Ancestor = Etype (Ancestor) then
18117 -- No further ancestors to examine
18122 Ancestor := Etype (Ancestor);
18126 end Is_Visible_Component;
18128 --------------------------
18129 -- Make_Class_Wide_Type --
18130 --------------------------
18132 procedure Make_Class_Wide_Type (T : Entity_Id) is
18133 CW_Type : Entity_Id;
18135 Next_E : Entity_Id;
18138 if Present (Class_Wide_Type (T)) then
18140 -- The class-wide type is a partially decorated entity created for a
18141 -- unanalyzed tagged type referenced through a limited with clause.
18142 -- When the tagged type is analyzed, its class-wide type needs to be
18143 -- redecorated. Note that we reuse the entity created by Decorate_
18144 -- Tagged_Type in order to preserve all links.
18146 if Materialize_Entity (Class_Wide_Type (T)) then
18147 CW_Type := Class_Wide_Type (T);
18148 Set_Materialize_Entity (CW_Type, False);
18150 -- The class wide type can have been defined by the partial view, in
18151 -- which case everything is already done.
18157 -- Default case, we need to create a new class-wide type
18161 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
18164 -- Inherit root type characteristics
18166 CW_Name := Chars (CW_Type);
18167 Next_E := Next_Entity (CW_Type);
18168 Copy_Node (T, CW_Type);
18169 Set_Comes_From_Source (CW_Type, False);
18170 Set_Chars (CW_Type, CW_Name);
18171 Set_Parent (CW_Type, Parent (T));
18172 Set_Next_Entity (CW_Type, Next_E);
18174 -- Ensure we have a new freeze node for the class-wide type. The partial
18175 -- view may have freeze action of its own, requiring a proper freeze
18176 -- node, and the same freeze node cannot be shared between the two
18179 Set_Has_Delayed_Freeze (CW_Type);
18180 Set_Freeze_Node (CW_Type, Empty);
18182 -- Customize the class-wide type: It has no prim. op., it cannot be
18183 -- abstract and its Etype points back to the specific root type.
18185 Set_Ekind (CW_Type, E_Class_Wide_Type);
18186 Set_Is_Tagged_Type (CW_Type, True);
18187 Set_Direct_Primitive_Operations (CW_Type, New_Elmt_List);
18188 Set_Is_Abstract_Type (CW_Type, False);
18189 Set_Is_Constrained (CW_Type, False);
18190 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
18191 Set_Default_SSO (CW_Type);
18193 if Ekind (T) = E_Class_Wide_Subtype then
18194 Set_Etype (CW_Type, Etype (Base_Type (T)));
18196 Set_Etype (CW_Type, T);
18199 Set_No_Tagged_Streams_Pragma (CW_Type, No_Tagged_Streams);
18201 -- If this is the class_wide type of a constrained subtype, it does
18202 -- not have discriminants.
18204 Set_Has_Discriminants (CW_Type,
18205 Has_Discriminants (T) and then not Is_Constrained (T));
18207 Set_Has_Unknown_Discriminants (CW_Type, True);
18208 Set_Class_Wide_Type (T, CW_Type);
18209 Set_Equivalent_Type (CW_Type, Empty);
18211 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
18213 Set_Class_Wide_Type (CW_Type, CW_Type);
18214 end Make_Class_Wide_Type;
18220 procedure Make_Index
18222 Related_Nod : Node_Id;
18223 Related_Id : Entity_Id := Empty;
18224 Suffix_Index : Nat := 1;
18225 In_Iter_Schm : Boolean := False)
18229 Def_Id : Entity_Id := Empty;
18230 Found : Boolean := False;
18233 -- For a discrete range used in a constrained array definition and
18234 -- defined by a range, an implicit conversion to the predefined type
18235 -- INTEGER is assumed if each bound is either a numeric literal, a named
18236 -- number, or an attribute, and the type of both bounds (prior to the
18237 -- implicit conversion) is the type universal_integer. Otherwise, both
18238 -- bounds must be of the same discrete type, other than universal
18239 -- integer; this type must be determinable independently of the
18240 -- context, but using the fact that the type must be discrete and that
18241 -- both bounds must have the same type.
18243 -- Character literals also have a universal type in the absence of
18244 -- of additional context, and are resolved to Standard_Character.
18246 if Nkind (N) = N_Range then
18248 -- The index is given by a range constraint. The bounds are known
18249 -- to be of a consistent type.
18251 if not Is_Overloaded (N) then
18254 -- For universal bounds, choose the specific predefined type
18256 if T = Universal_Integer then
18257 T := Standard_Integer;
18259 elsif T = Any_Character then
18260 Ambiguous_Character (Low_Bound (N));
18262 T := Standard_Character;
18265 -- The node may be overloaded because some user-defined operators
18266 -- are available, but if a universal interpretation exists it is
18267 -- also the selected one.
18269 elsif Universal_Interpretation (N) = Universal_Integer then
18270 T := Standard_Integer;
18276 Ind : Interp_Index;
18280 Get_First_Interp (N, Ind, It);
18281 while Present (It.Typ) loop
18282 if Is_Discrete_Type (It.Typ) then
18285 and then not Covers (It.Typ, T)
18286 and then not Covers (T, It.Typ)
18288 Error_Msg_N ("ambiguous bounds in discrete range", N);
18296 Get_Next_Interp (Ind, It);
18299 if T = Any_Type then
18300 Error_Msg_N ("discrete type required for range", N);
18301 Set_Etype (N, Any_Type);
18304 elsif T = Universal_Integer then
18305 T := Standard_Integer;
18310 if not Is_Discrete_Type (T) then
18311 Error_Msg_N ("discrete type required for range", N);
18312 Set_Etype (N, Any_Type);
18316 if Nkind (Low_Bound (N)) = N_Attribute_Reference
18317 and then Attribute_Name (Low_Bound (N)) = Name_First
18318 and then Is_Entity_Name (Prefix (Low_Bound (N)))
18319 and then Is_Type (Entity (Prefix (Low_Bound (N))))
18320 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (N))))
18322 -- The type of the index will be the type of the prefix, as long
18323 -- as the upper bound is 'Last of the same type.
18325 Def_Id := Entity (Prefix (Low_Bound (N)));
18327 if Nkind (High_Bound (N)) /= N_Attribute_Reference
18328 or else Attribute_Name (High_Bound (N)) /= Name_Last
18329 or else not Is_Entity_Name (Prefix (High_Bound (N)))
18330 or else Entity (Prefix (High_Bound (N))) /= Def_Id
18337 Process_Range_Expr_In_Decl (R, T, In_Iter_Schm => In_Iter_Schm);
18339 elsif Nkind (N) = N_Subtype_Indication then
18341 -- The index is given by a subtype with a range constraint
18343 T := Base_Type (Entity (Subtype_Mark (N)));
18345 if not Is_Discrete_Type (T) then
18346 Error_Msg_N ("discrete type required for range", N);
18347 Set_Etype (N, Any_Type);
18351 R := Range_Expression (Constraint (N));
18354 Process_Range_Expr_In_Decl
18355 (R, Entity (Subtype_Mark (N)), In_Iter_Schm => In_Iter_Schm);
18357 elsif Nkind (N) = N_Attribute_Reference then
18359 -- Catch beginner's error (use of attribute other than 'Range)
18361 if Attribute_Name (N) /= Name_Range then
18362 Error_Msg_N ("expect attribute ''Range", N);
18363 Set_Etype (N, Any_Type);
18367 -- If the node denotes the range of a type mark, that is also the
18368 -- resulting type, and we do not need to create an Itype for it.
18370 if Is_Entity_Name (Prefix (N))
18371 and then Comes_From_Source (N)
18372 and then Is_Type (Entity (Prefix (N)))
18373 and then Is_Discrete_Type (Entity (Prefix (N)))
18375 Def_Id := Entity (Prefix (N));
18378 Analyze_And_Resolve (N);
18382 -- If none of the above, must be a subtype. We convert this to a
18383 -- range attribute reference because in the case of declared first
18384 -- named subtypes, the types in the range reference can be different
18385 -- from the type of the entity. A range attribute normalizes the
18386 -- reference and obtains the correct types for the bounds.
18388 -- This transformation is in the nature of an expansion, is only
18389 -- done if expansion is active. In particular, it is not done on
18390 -- formal generic types, because we need to retain the name of the
18391 -- original index for instantiation purposes.
18394 if not Is_Entity_Name (N) or else not Is_Type (Entity (N)) then
18395 Error_Msg_N ("invalid subtype mark in discrete range ", N);
18396 Set_Etype (N, Any_Integer);
18400 -- The type mark may be that of an incomplete type. It is only
18401 -- now that we can get the full view, previous analysis does
18402 -- not look specifically for a type mark.
18404 Set_Entity (N, Get_Full_View (Entity (N)));
18405 Set_Etype (N, Entity (N));
18406 Def_Id := Entity (N);
18408 if not Is_Discrete_Type (Def_Id) then
18409 Error_Msg_N ("discrete type required for index", N);
18410 Set_Etype (N, Any_Type);
18415 if Expander_Active then
18417 Make_Attribute_Reference (Sloc (N),
18418 Attribute_Name => Name_Range,
18419 Prefix => Relocate_Node (N)));
18421 -- The original was a subtype mark that does not freeze. This
18422 -- means that the rewritten version must not freeze either.
18424 Set_Must_Not_Freeze (N);
18425 Set_Must_Not_Freeze (Prefix (N));
18426 Analyze_And_Resolve (N);
18430 -- If expander is inactive, type is legal, nothing else to construct
18437 if not Is_Discrete_Type (T) then
18438 Error_Msg_N ("discrete type required for range", N);
18439 Set_Etype (N, Any_Type);
18442 elsif T = Any_Type then
18443 Set_Etype (N, Any_Type);
18447 -- We will now create the appropriate Itype to describe the range, but
18448 -- first a check. If we originally had a subtype, then we just label
18449 -- the range with this subtype. Not only is there no need to construct
18450 -- a new subtype, but it is wrong to do so for two reasons:
18452 -- 1. A legality concern, if we have a subtype, it must not freeze,
18453 -- and the Itype would cause freezing incorrectly
18455 -- 2. An efficiency concern, if we created an Itype, it would not be
18456 -- recognized as the same type for the purposes of eliminating
18457 -- checks in some circumstances.
18459 -- We signal this case by setting the subtype entity in Def_Id
18461 if No (Def_Id) then
18463 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
18464 Set_Etype (Def_Id, Base_Type (T));
18466 if Is_Signed_Integer_Type (T) then
18467 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
18469 elsif Is_Modular_Integer_Type (T) then
18470 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
18473 Set_Ekind (Def_Id, E_Enumeration_Subtype);
18474 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
18475 Set_First_Literal (Def_Id, First_Literal (T));
18478 Set_Size_Info (Def_Id, (T));
18479 Set_RM_Size (Def_Id, RM_Size (T));
18480 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
18482 Set_Scalar_Range (Def_Id, R);
18483 Conditional_Delay (Def_Id, T);
18485 if Nkind (N) = N_Subtype_Indication then
18486 Inherit_Predicate_Flags (Def_Id, Entity (Subtype_Mark (N)));
18489 -- In the subtype indication case, if the immediate parent of the
18490 -- new subtype is non-static, then the subtype we create is non-
18491 -- static, even if its bounds are static.
18493 if Nkind (N) = N_Subtype_Indication
18494 and then not Is_OK_Static_Subtype (Entity (Subtype_Mark (N)))
18496 Set_Is_Non_Static_Subtype (Def_Id);
18500 -- Final step is to label the index with this constructed type
18502 Set_Etype (N, Def_Id);
18505 ------------------------------
18506 -- Modular_Type_Declaration --
18507 ------------------------------
18509 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
18510 Mod_Expr : constant Node_Id := Expression (Def);
18513 procedure Set_Modular_Size (Bits : Int);
18514 -- Sets RM_Size to Bits, and Esize to normal word size above this
18516 ----------------------
18517 -- Set_Modular_Size --
18518 ----------------------
18520 procedure Set_Modular_Size (Bits : Int) is
18522 Set_RM_Size (T, UI_From_Int (Bits));
18527 elsif Bits <= 16 then
18528 Init_Esize (T, 16);
18530 elsif Bits <= 32 then
18531 Init_Esize (T, 32);
18534 Init_Esize (T, System_Max_Binary_Modulus_Power);
18537 if not Non_Binary_Modulus (T) and then Esize (T) = RM_Size (T) then
18538 Set_Is_Known_Valid (T);
18540 end Set_Modular_Size;
18542 -- Start of processing for Modular_Type_Declaration
18545 -- If the mod expression is (exactly) 2 * literal, where literal is
18546 -- 64 or less,then almost certainly the * was meant to be **. Warn.
18548 if Warn_On_Suspicious_Modulus_Value
18549 and then Nkind (Mod_Expr) = N_Op_Multiply
18550 and then Nkind (Left_Opnd (Mod_Expr)) = N_Integer_Literal
18551 and then Intval (Left_Opnd (Mod_Expr)) = Uint_2
18552 and then Nkind (Right_Opnd (Mod_Expr)) = N_Integer_Literal
18553 and then Intval (Right_Opnd (Mod_Expr)) <= Uint_64
18556 ("suspicious MOD value, was '*'* intended'??M?", Mod_Expr);
18559 -- Proceed with analysis of mod expression
18561 Analyze_And_Resolve (Mod_Expr, Any_Integer);
18563 Set_Ekind (T, E_Modular_Integer_Type);
18564 Init_Alignment (T);
18565 Set_Is_Constrained (T);
18567 if not Is_OK_Static_Expression (Mod_Expr) then
18568 Flag_Non_Static_Expr
18569 ("non-static expression used for modular type bound!", Mod_Expr);
18570 M_Val := 2 ** System_Max_Binary_Modulus_Power;
18572 M_Val := Expr_Value (Mod_Expr);
18576 Error_Msg_N ("modulus value must be positive", Mod_Expr);
18577 M_Val := 2 ** System_Max_Binary_Modulus_Power;
18580 if M_Val > 2 ** Standard_Long_Integer_Size then
18581 Check_Restriction (No_Long_Long_Integers, Mod_Expr);
18584 Set_Modulus (T, M_Val);
18586 -- Create bounds for the modular type based on the modulus given in
18587 -- the type declaration and then analyze and resolve those bounds.
18589 Set_Scalar_Range (T,
18590 Make_Range (Sloc (Mod_Expr),
18591 Low_Bound => Make_Integer_Literal (Sloc (Mod_Expr), 0),
18592 High_Bound => Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
18594 -- Properly analyze the literals for the range. We do this manually
18595 -- because we can't go calling Resolve, since we are resolving these
18596 -- bounds with the type, and this type is certainly not complete yet.
18598 Set_Etype (Low_Bound (Scalar_Range (T)), T);
18599 Set_Etype (High_Bound (Scalar_Range (T)), T);
18600 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
18601 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
18603 -- Loop through powers of two to find number of bits required
18605 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
18609 if M_Val = 2 ** Bits then
18610 Set_Modular_Size (Bits);
18615 elsif M_Val < 2 ** Bits then
18616 Check_SPARK_05_Restriction ("modulus should be a power of 2", T);
18617 Set_Non_Binary_Modulus (T);
18619 if Bits > System_Max_Nonbinary_Modulus_Power then
18620 Error_Msg_Uint_1 :=
18621 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
18623 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
18624 Set_Modular_Size (System_Max_Binary_Modulus_Power);
18628 -- In the nonbinary case, set size as per RM 13.3(55)
18630 Set_Modular_Size (Bits);
18637 -- If we fall through, then the size exceed System.Max_Binary_Modulus
18638 -- so we just signal an error and set the maximum size.
18640 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
18641 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
18643 Set_Modular_Size (System_Max_Binary_Modulus_Power);
18644 Init_Alignment (T);
18646 end Modular_Type_Declaration;
18648 --------------------------
18649 -- New_Concatenation_Op --
18650 --------------------------
18652 procedure New_Concatenation_Op (Typ : Entity_Id) is
18653 Loc : constant Source_Ptr := Sloc (Typ);
18656 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
18657 -- Create abbreviated declaration for the formal of a predefined
18658 -- Operator 'Op' of type 'Typ'
18660 --------------------
18661 -- Make_Op_Formal --
18662 --------------------
18664 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
18665 Formal : Entity_Id;
18667 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
18668 Set_Etype (Formal, Typ);
18669 Set_Mechanism (Formal, Default_Mechanism);
18671 end Make_Op_Formal;
18673 -- Start of processing for New_Concatenation_Op
18676 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
18678 Set_Ekind (Op, E_Operator);
18679 Set_Scope (Op, Current_Scope);
18680 Set_Etype (Op, Typ);
18681 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
18682 Set_Is_Immediately_Visible (Op);
18683 Set_Is_Intrinsic_Subprogram (Op);
18684 Set_Has_Completion (Op);
18685 Append_Entity (Op, Current_Scope);
18687 Set_Name_Entity_Id (Name_Op_Concat, Op);
18689 Append_Entity (Make_Op_Formal (Typ, Op), Op);
18690 Append_Entity (Make_Op_Formal (Typ, Op), Op);
18691 end New_Concatenation_Op;
18693 -------------------------
18694 -- OK_For_Limited_Init --
18695 -------------------------
18697 -- ???Check all calls of this, and compare the conditions under which it's
18700 function OK_For_Limited_Init
18702 Exp : Node_Id) return Boolean
18705 return Is_CPP_Constructor_Call (Exp)
18706 or else (Ada_Version >= Ada_2005
18707 and then not Debug_Flag_Dot_L
18708 and then OK_For_Limited_Init_In_05 (Typ, Exp));
18709 end OK_For_Limited_Init;
18711 -------------------------------
18712 -- OK_For_Limited_Init_In_05 --
18713 -------------------------------
18715 function OK_For_Limited_Init_In_05
18717 Exp : Node_Id) return Boolean
18720 -- An object of a limited interface type can be initialized with any
18721 -- expression of a nonlimited descendant type.
18723 if Is_Class_Wide_Type (Typ)
18724 and then Is_Limited_Interface (Typ)
18725 and then not Is_Limited_Type (Etype (Exp))
18730 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
18731 -- case of limited aggregates (including extension aggregates), and
18732 -- function calls. The function call may have been given in prefixed
18733 -- notation, in which case the original node is an indexed component.
18734 -- If the function is parameterless, the original node was an explicit
18735 -- dereference. The function may also be parameterless, in which case
18736 -- the source node is just an identifier.
18738 case Nkind (Original_Node (Exp)) is
18739 when N_Aggregate | N_Extension_Aggregate | N_Function_Call | N_Op =>
18742 when N_Identifier =>
18743 return Present (Entity (Original_Node (Exp)))
18744 and then Ekind (Entity (Original_Node (Exp))) = E_Function;
18746 when N_Qualified_Expression =>
18748 OK_For_Limited_Init_In_05
18749 (Typ, Expression (Original_Node (Exp)));
18751 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
18752 -- with a function call, the expander has rewritten the call into an
18753 -- N_Type_Conversion node to force displacement of the pointer to
18754 -- reference the component containing the secondary dispatch table.
18755 -- Otherwise a type conversion is not a legal context.
18756 -- A return statement for a build-in-place function returning a
18757 -- synchronized type also introduces an unchecked conversion.
18759 when N_Type_Conversion |
18760 N_Unchecked_Type_Conversion =>
18761 return not Comes_From_Source (Exp)
18763 OK_For_Limited_Init_In_05
18764 (Typ, Expression (Original_Node (Exp)));
18766 when N_Indexed_Component |
18767 N_Selected_Component |
18768 N_Explicit_Dereference =>
18769 return Nkind (Exp) = N_Function_Call;
18771 -- A use of 'Input is a function call, hence allowed. Normally the
18772 -- attribute will be changed to a call, but the attribute by itself
18773 -- can occur with -gnatc.
18775 when N_Attribute_Reference =>
18776 return Attribute_Name (Original_Node (Exp)) = Name_Input;
18778 -- For a case expression, all dependent expressions must be legal
18780 when N_Case_Expression =>
18785 Alt := First (Alternatives (Original_Node (Exp)));
18786 while Present (Alt) loop
18787 if not OK_For_Limited_Init_In_05 (Typ, Expression (Alt)) then
18797 -- For an if expression, all dependent expressions must be legal
18799 when N_If_Expression =>
18801 Then_Expr : constant Node_Id :=
18802 Next (First (Expressions (Original_Node (Exp))));
18803 Else_Expr : constant Node_Id := Next (Then_Expr);
18805 return OK_For_Limited_Init_In_05 (Typ, Then_Expr)
18807 OK_For_Limited_Init_In_05 (Typ, Else_Expr);
18813 end OK_For_Limited_Init_In_05;
18815 -------------------------------------------
18816 -- Ordinary_Fixed_Point_Type_Declaration --
18817 -------------------------------------------
18819 procedure Ordinary_Fixed_Point_Type_Declaration
18823 Loc : constant Source_Ptr := Sloc (Def);
18824 Delta_Expr : constant Node_Id := Delta_Expression (Def);
18825 RRS : constant Node_Id := Real_Range_Specification (Def);
18826 Implicit_Base : Entity_Id;
18833 Check_Restriction (No_Fixed_Point, Def);
18835 -- Create implicit base type
18838 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
18839 Set_Etype (Implicit_Base, Implicit_Base);
18841 -- Analyze and process delta expression
18843 Analyze_And_Resolve (Delta_Expr, Any_Real);
18845 Check_Delta_Expression (Delta_Expr);
18846 Delta_Val := Expr_Value_R (Delta_Expr);
18848 Set_Delta_Value (Implicit_Base, Delta_Val);
18850 -- Compute default small from given delta, which is the largest power
18851 -- of two that does not exceed the given delta value.
18861 if Delta_Val < Ureal_1 then
18862 while Delta_Val < Tmp loop
18863 Tmp := Tmp / Ureal_2;
18864 Scale := Scale + 1;
18869 Tmp := Tmp * Ureal_2;
18870 exit when Tmp > Delta_Val;
18871 Scale := Scale - 1;
18875 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
18878 Set_Small_Value (Implicit_Base, Small_Val);
18880 -- If no range was given, set a dummy range
18882 if RRS <= Empty_Or_Error then
18883 Low_Val := -Small_Val;
18884 High_Val := Small_Val;
18886 -- Otherwise analyze and process given range
18890 Low : constant Node_Id := Low_Bound (RRS);
18891 High : constant Node_Id := High_Bound (RRS);
18894 Analyze_And_Resolve (Low, Any_Real);
18895 Analyze_And_Resolve (High, Any_Real);
18896 Check_Real_Bound (Low);
18897 Check_Real_Bound (High);
18899 -- Obtain and set the range
18901 Low_Val := Expr_Value_R (Low);
18902 High_Val := Expr_Value_R (High);
18904 if Low_Val > High_Val then
18905 Error_Msg_NE ("??fixed point type& has null range", Def, T);
18910 -- The range for both the implicit base and the declared first subtype
18911 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
18912 -- set a temporary range in place. Note that the bounds of the base
18913 -- type will be widened to be symmetrical and to fill the available
18914 -- bits when the type is frozen.
18916 -- We could do this with all discrete types, and probably should, but
18917 -- we absolutely have to do it for fixed-point, since the end-points
18918 -- of the range and the size are determined by the small value, which
18919 -- could be reset before the freeze point.
18921 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
18922 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
18924 -- Complete definition of first subtype. The inheritance of the rep item
18925 -- chain ensures that SPARK-related pragmas are not clobbered when the
18926 -- ordinary fixed point type acts as a full view of a private type.
18928 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
18929 Set_Etype (T, Implicit_Base);
18930 Init_Size_Align (T);
18931 Inherit_Rep_Item_Chain (T, Implicit_Base);
18932 Set_Small_Value (T, Small_Val);
18933 Set_Delta_Value (T, Delta_Val);
18934 Set_Is_Constrained (T);
18935 end Ordinary_Fixed_Point_Type_Declaration;
18937 ----------------------------------
18938 -- Preanalyze_Assert_Expression --
18939 ----------------------------------
18941 procedure Preanalyze_Assert_Expression (N : Node_Id; T : Entity_Id) is
18943 In_Assertion_Expr := In_Assertion_Expr + 1;
18944 Preanalyze_Spec_Expression (N, T);
18945 In_Assertion_Expr := In_Assertion_Expr - 1;
18946 end Preanalyze_Assert_Expression;
18948 -----------------------------------
18949 -- Preanalyze_Default_Expression --
18950 -----------------------------------
18952 procedure Preanalyze_Default_Expression (N : Node_Id; T : Entity_Id) is
18953 Save_In_Default_Expr : constant Boolean := In_Default_Expr;
18955 In_Default_Expr := True;
18956 Preanalyze_Spec_Expression (N, T);
18957 In_Default_Expr := Save_In_Default_Expr;
18958 end Preanalyze_Default_Expression;
18960 --------------------------------
18961 -- Preanalyze_Spec_Expression --
18962 --------------------------------
18964 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
18965 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
18967 In_Spec_Expression := True;
18968 Preanalyze_And_Resolve (N, T);
18969 In_Spec_Expression := Save_In_Spec_Expression;
18970 end Preanalyze_Spec_Expression;
18972 ----------------------------------------
18973 -- Prepare_Private_Subtype_Completion --
18974 ----------------------------------------
18976 procedure Prepare_Private_Subtype_Completion
18978 Related_Nod : Node_Id)
18980 Id_B : constant Entity_Id := Base_Type (Id);
18981 Full_B : Entity_Id := Full_View (Id_B);
18985 if Present (Full_B) then
18987 -- Get to the underlying full view if necessary
18989 if Is_Private_Type (Full_B)
18990 and then Present (Underlying_Full_View (Full_B))
18992 Full_B := Underlying_Full_View (Full_B);
18995 -- The Base_Type is already completed, we can complete the subtype
18996 -- now. We have to create a new entity with the same name, Thus we
18997 -- can't use Create_Itype.
18999 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
19000 Set_Is_Itype (Full);
19001 Set_Associated_Node_For_Itype (Full, Related_Nod);
19002 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
19005 -- The parent subtype may be private, but the base might not, in some
19006 -- nested instances. In that case, the subtype does not need to be
19007 -- exchanged. It would still be nice to make private subtypes and their
19008 -- bases consistent at all times ???
19010 if Is_Private_Type (Id_B) then
19011 Append_Elmt (Id, Private_Dependents (Id_B));
19013 end Prepare_Private_Subtype_Completion;
19015 ---------------------------
19016 -- Process_Discriminants --
19017 ---------------------------
19019 procedure Process_Discriminants
19021 Prev : Entity_Id := Empty)
19023 Elist : constant Elist_Id := New_Elmt_List;
19026 Discr_Number : Uint;
19027 Discr_Type : Entity_Id;
19028 Default_Present : Boolean := False;
19029 Default_Not_Present : Boolean := False;
19032 -- A composite type other than an array type can have discriminants.
19033 -- On entry, the current scope is the composite type.
19035 -- The discriminants are initially entered into the scope of the type
19036 -- via Enter_Name with the default Ekind of E_Void to prevent premature
19037 -- use, as explained at the end of this procedure.
19039 Discr := First (Discriminant_Specifications (N));
19040 while Present (Discr) loop
19041 Enter_Name (Defining_Identifier (Discr));
19043 -- For navigation purposes we add a reference to the discriminant
19044 -- in the entity for the type. If the current declaration is a
19045 -- completion, place references on the partial view. Otherwise the
19046 -- type is the current scope.
19048 if Present (Prev) then
19050 -- The references go on the partial view, if present. If the
19051 -- partial view has discriminants, the references have been
19052 -- generated already.
19054 if not Has_Discriminants (Prev) then
19055 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
19059 (Current_Scope, Defining_Identifier (Discr), 'd');
19062 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
19063 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
19065 -- Ada 2005 (AI-254)
19067 if Present (Access_To_Subprogram_Definition
19068 (Discriminant_Type (Discr)))
19069 and then Protected_Present (Access_To_Subprogram_Definition
19070 (Discriminant_Type (Discr)))
19073 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
19077 Find_Type (Discriminant_Type (Discr));
19078 Discr_Type := Etype (Discriminant_Type (Discr));
19080 if Error_Posted (Discriminant_Type (Discr)) then
19081 Discr_Type := Any_Type;
19085 -- Handling of discriminants that are access types
19087 if Is_Access_Type (Discr_Type) then
19089 -- Ada 2005 (AI-230): Access discriminant allowed in non-
19090 -- limited record types
19092 if Ada_Version < Ada_2005 then
19093 Check_Access_Discriminant_Requires_Limited
19094 (Discr, Discriminant_Type (Discr));
19097 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
19099 ("(Ada 83) access discriminant not allowed", Discr);
19102 -- If not access type, must be a discrete type
19104 elsif not Is_Discrete_Type (Discr_Type) then
19106 ("discriminants must have a discrete or access type",
19107 Discriminant_Type (Discr));
19110 Set_Etype (Defining_Identifier (Discr), Discr_Type);
19112 -- If a discriminant specification includes the assignment compound
19113 -- delimiter followed by an expression, the expression is the default
19114 -- expression of the discriminant; the default expression must be of
19115 -- the type of the discriminant. (RM 3.7.1) Since this expression is
19116 -- a default expression, we do the special preanalysis, since this
19117 -- expression does not freeze (see section "Handling of Default and
19118 -- Per-Object Expressions" in spec of package Sem).
19120 if Present (Expression (Discr)) then
19121 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
19125 if Nkind (N) = N_Formal_Type_Declaration then
19127 ("discriminant defaults not allowed for formal type",
19128 Expression (Discr));
19130 -- Flag an error for a tagged type with defaulted discriminants,
19131 -- excluding limited tagged types when compiling for Ada 2012
19132 -- (see AI05-0214).
19134 elsif Is_Tagged_Type (Current_Scope)
19135 and then (not Is_Limited_Type (Current_Scope)
19136 or else Ada_Version < Ada_2012)
19137 and then Comes_From_Source (N)
19139 -- Note: see similar test in Check_Or_Process_Discriminants, to
19140 -- handle the (illegal) case of the completion of an untagged
19141 -- view with discriminants with defaults by a tagged full view.
19142 -- We skip the check if Discr does not come from source, to
19143 -- account for the case of an untagged derived type providing
19144 -- defaults for a renamed discriminant from a private untagged
19145 -- ancestor with a tagged full view (ACATS B460006).
19147 if Ada_Version >= Ada_2012 then
19149 ("discriminants of nonlimited tagged type cannot have"
19151 Expression (Discr));
19154 ("discriminants of tagged type cannot have defaults",
19155 Expression (Discr));
19159 Default_Present := True;
19160 Append_Elmt (Expression (Discr), Elist);
19162 -- Tag the defining identifiers for the discriminants with
19163 -- their corresponding default expressions from the tree.
19165 Set_Discriminant_Default_Value
19166 (Defining_Identifier (Discr), Expression (Discr));
19169 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag
19170 -- gets set unless we can be sure that no range check is required.
19172 if (GNATprove_Mode or not Expander_Active)
19175 (Expression (Discr), Discr_Type, Assume_Valid => True)
19177 Set_Do_Range_Check (Expression (Discr));
19180 -- No default discriminant value given
19183 Default_Not_Present := True;
19186 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
19187 -- Discr_Type but with the null-exclusion attribute
19189 if Ada_Version >= Ada_2005 then
19191 -- Ada 2005 (AI-231): Static checks
19193 if Can_Never_Be_Null (Discr_Type) then
19194 Null_Exclusion_Static_Checks (Discr);
19196 elsif Is_Access_Type (Discr_Type)
19197 and then Null_Exclusion_Present (Discr)
19199 -- No need to check itypes because in their case this check
19200 -- was done at their point of creation
19202 and then not Is_Itype (Discr_Type)
19204 if Can_Never_Be_Null (Discr_Type) then
19206 ("`NOT NULL` not allowed (& already excludes null)",
19211 Set_Etype (Defining_Identifier (Discr),
19212 Create_Null_Excluding_Itype
19214 Related_Nod => Discr));
19216 -- Check for improper null exclusion if the type is otherwise
19217 -- legal for a discriminant.
19219 elsif Null_Exclusion_Present (Discr)
19220 and then Is_Discrete_Type (Discr_Type)
19223 ("null exclusion can only apply to an access type", Discr);
19226 -- Ada 2005 (AI-402): access discriminants of nonlimited types
19227 -- can't have defaults. Synchronized types, or types that are
19228 -- explicitly limited are fine, but special tests apply to derived
19229 -- types in generics: in a generic body we have to assume the
19230 -- worst, and therefore defaults are not allowed if the parent is
19231 -- a generic formal private type (see ACATS B370001).
19233 if Is_Access_Type (Discr_Type) and then Default_Present then
19234 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
19235 or else Is_Limited_Record (Current_Scope)
19236 or else Is_Concurrent_Type (Current_Scope)
19237 or else Is_Concurrent_Record_Type (Current_Scope)
19238 or else Ekind (Current_Scope) = E_Limited_Private_Type
19240 if not Is_Derived_Type (Current_Scope)
19241 or else not Is_Generic_Type (Etype (Current_Scope))
19242 or else not In_Package_Body (Scope (Etype (Current_Scope)))
19243 or else Limited_Present
19244 (Type_Definition (Parent (Current_Scope)))
19250 ("access discriminants of nonlimited types cannot "
19251 & "have defaults", Expression (Discr));
19254 elsif Present (Expression (Discr)) then
19256 ("(Ada 2005) access discriminants of nonlimited types "
19257 & "cannot have defaults", Expression (Discr));
19262 -- A discriminant cannot be effectively volatile. This check is only
19263 -- relevant when SPARK_Mode is on as it is not standard Ada legality
19264 -- rule (SPARK RM 7.1.3(6)).
19267 and then Is_Effectively_Volatile (Defining_Identifier (Discr))
19269 Error_Msg_N ("discriminant cannot be volatile", Discr);
19275 -- An element list consisting of the default expressions of the
19276 -- discriminants is constructed in the above loop and used to set
19277 -- the Discriminant_Constraint attribute for the type. If an object
19278 -- is declared of this (record or task) type without any explicit
19279 -- discriminant constraint given, this element list will form the
19280 -- actual parameters for the corresponding initialization procedure
19283 Set_Discriminant_Constraint (Current_Scope, Elist);
19284 Set_Stored_Constraint (Current_Scope, No_Elist);
19286 -- Default expressions must be provided either for all or for none
19287 -- of the discriminants of a discriminant part. (RM 3.7.1)
19289 if Default_Present and then Default_Not_Present then
19291 ("incomplete specification of defaults for discriminants", N);
19294 -- The use of the name of a discriminant is not allowed in default
19295 -- expressions of a discriminant part if the specification of the
19296 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
19298 -- To detect this, the discriminant names are entered initially with an
19299 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
19300 -- attempt to use a void entity (for example in an expression that is
19301 -- type-checked) produces the error message: premature usage. Now after
19302 -- completing the semantic analysis of the discriminant part, we can set
19303 -- the Ekind of all the discriminants appropriately.
19305 Discr := First (Discriminant_Specifications (N));
19306 Discr_Number := Uint_1;
19307 while Present (Discr) loop
19308 Id := Defining_Identifier (Discr);
19309 Set_Ekind (Id, E_Discriminant);
19310 Init_Component_Location (Id);
19312 Set_Discriminant_Number (Id, Discr_Number);
19314 -- Make sure this is always set, even in illegal programs
19316 Set_Corresponding_Discriminant (Id, Empty);
19318 -- Initialize the Original_Record_Component to the entity itself.
19319 -- Inherit_Components will propagate the right value to
19320 -- discriminants in derived record types.
19322 Set_Original_Record_Component (Id, Id);
19324 -- Create the discriminal for the discriminant
19326 Build_Discriminal (Id);
19329 Discr_Number := Discr_Number + 1;
19332 Set_Has_Discriminants (Current_Scope);
19333 end Process_Discriminants;
19335 -----------------------
19336 -- Process_Full_View --
19337 -----------------------
19339 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
19340 procedure Collect_Implemented_Interfaces
19342 Ifaces : Elist_Id);
19343 -- Ada 2005: Gather all the interfaces that Typ directly or
19344 -- inherently implements. Duplicate entries are not added to
19345 -- the list Ifaces.
19347 ------------------------------------
19348 -- Collect_Implemented_Interfaces --
19349 ------------------------------------
19351 procedure Collect_Implemented_Interfaces
19356 Iface_Elmt : Elmt_Id;
19359 -- Abstract interfaces are only associated with tagged record types
19361 if not Is_Tagged_Type (Typ) or else not Is_Record_Type (Typ) then
19365 -- Recursively climb to the ancestors
19367 if Etype (Typ) /= Typ
19369 -- Protect the frontend against wrong cyclic declarations like:
19371 -- type B is new A with private;
19372 -- type C is new A with private;
19374 -- type B is new C with null record;
19375 -- type C is new B with null record;
19377 and then Etype (Typ) /= Priv_T
19378 and then Etype (Typ) /= Full_T
19380 -- Keep separate the management of private type declarations
19382 if Ekind (Typ) = E_Record_Type_With_Private then
19384 -- Handle the following illegal usage:
19385 -- type Private_Type is tagged private;
19387 -- type Private_Type is new Type_Implementing_Iface;
19389 if Present (Full_View (Typ))
19390 and then Etype (Typ) /= Full_View (Typ)
19392 if Is_Interface (Etype (Typ)) then
19393 Append_Unique_Elmt (Etype (Typ), Ifaces);
19396 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
19399 -- Non-private types
19402 if Is_Interface (Etype (Typ)) then
19403 Append_Unique_Elmt (Etype (Typ), Ifaces);
19406 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
19410 -- Handle entities in the list of abstract interfaces
19412 if Present (Interfaces (Typ)) then
19413 Iface_Elmt := First_Elmt (Interfaces (Typ));
19414 while Present (Iface_Elmt) loop
19415 Iface := Node (Iface_Elmt);
19417 pragma Assert (Is_Interface (Iface));
19419 if not Contain_Interface (Iface, Ifaces) then
19420 Append_Elmt (Iface, Ifaces);
19421 Collect_Implemented_Interfaces (Iface, Ifaces);
19424 Next_Elmt (Iface_Elmt);
19427 end Collect_Implemented_Interfaces;
19431 Full_Indic : Node_Id;
19432 Full_Parent : Entity_Id;
19433 Priv_Parent : Entity_Id;
19435 -- Start of processing for Process_Full_View
19438 -- First some sanity checks that must be done after semantic
19439 -- decoration of the full view and thus cannot be placed with other
19440 -- similar checks in Find_Type_Name
19442 if not Is_Limited_Type (Priv_T)
19443 and then (Is_Limited_Type (Full_T)
19444 or else Is_Limited_Composite (Full_T))
19446 if In_Instance then
19450 ("completion of nonlimited type cannot be limited", Full_T);
19451 Explain_Limited_Type (Full_T, Full_T);
19454 elsif Is_Abstract_Type (Full_T)
19455 and then not Is_Abstract_Type (Priv_T)
19458 ("completion of nonabstract type cannot be abstract", Full_T);
19460 elsif Is_Tagged_Type (Priv_T)
19461 and then Is_Limited_Type (Priv_T)
19462 and then not Is_Limited_Type (Full_T)
19464 -- If pragma CPP_Class was applied to the private declaration
19465 -- propagate the limitedness to the full-view
19467 if Is_CPP_Class (Priv_T) then
19468 Set_Is_Limited_Record (Full_T);
19470 -- GNAT allow its own definition of Limited_Controlled to disobey
19471 -- this rule in order in ease the implementation. This test is safe
19472 -- because Root_Controlled is defined in a child of System that
19473 -- normal programs are not supposed to use.
19475 elsif Is_RTE (Etype (Full_T), RE_Root_Controlled) then
19476 Set_Is_Limited_Composite (Full_T);
19479 ("completion of limited tagged type must be limited", Full_T);
19482 elsif Is_Generic_Type (Priv_T) then
19483 Error_Msg_N ("generic type cannot have a completion", Full_T);
19486 -- Check that ancestor interfaces of private and full views are
19487 -- consistent. We omit this check for synchronized types because
19488 -- they are performed on the corresponding record type when frozen.
19490 if Ada_Version >= Ada_2005
19491 and then Is_Tagged_Type (Priv_T)
19492 and then Is_Tagged_Type (Full_T)
19493 and then not Is_Concurrent_Type (Full_T)
19497 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
19498 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
19501 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
19502 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
19504 -- Ada 2005 (AI-251): The partial view shall be a descendant of
19505 -- an interface type if and only if the full type is descendant
19506 -- of the interface type (AARM 7.3 (7.3/2)).
19508 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
19510 if Present (Iface) then
19512 ("interface in partial view& not implemented by full type "
19513 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
19516 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
19518 if Present (Iface) then
19520 ("interface & not implemented by partial view "
19521 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
19526 if Is_Tagged_Type (Priv_T)
19527 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19528 and then Is_Derived_Type (Full_T)
19530 Priv_Parent := Etype (Priv_T);
19532 -- The full view of a private extension may have been transformed
19533 -- into an unconstrained derived type declaration and a subtype
19534 -- declaration (see build_derived_record_type for details).
19536 if Nkind (N) = N_Subtype_Declaration then
19537 Full_Indic := Subtype_Indication (N);
19538 Full_Parent := Etype (Base_Type (Full_T));
19540 Full_Indic := Subtype_Indication (Type_Definition (N));
19541 Full_Parent := Etype (Full_T);
19544 -- Check that the parent type of the full type is a descendant of
19545 -- the ancestor subtype given in the private extension. If either
19546 -- entity has an Etype equal to Any_Type then we had some previous
19547 -- error situation [7.3(8)].
19549 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
19552 -- Ada 2005 (AI-251): Interfaces in the full type can be given in
19553 -- any order. Therefore we don't have to check that its parent must
19554 -- be a descendant of the parent of the private type declaration.
19556 elsif Is_Interface (Priv_Parent)
19557 and then Is_Interface (Full_Parent)
19561 -- Ada 2005 (AI-251): If the parent of the private type declaration
19562 -- is an interface there is no need to check that it is an ancestor
19563 -- of the associated full type declaration. The required tests for
19564 -- this case are performed by Build_Derived_Record_Type.
19566 elsif not Is_Interface (Base_Type (Priv_Parent))
19567 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
19570 ("parent of full type must descend from parent"
19571 & " of private extension", Full_Indic);
19573 -- First check a formal restriction, and then proceed with checking
19574 -- Ada rules. Since the formal restriction is not a serious error, we
19575 -- don't prevent further error detection for this check, hence the
19579 -- In formal mode, when completing a private extension the type
19580 -- named in the private part must be exactly the same as that
19581 -- named in the visible part.
19583 if Priv_Parent /= Full_Parent then
19584 Error_Msg_Name_1 := Chars (Priv_Parent);
19585 Check_SPARK_05_Restriction ("% expected", Full_Indic);
19588 -- Check the rules of 7.3(10): if the private extension inherits
19589 -- known discriminants, then the full type must also inherit those
19590 -- discriminants from the same (ancestor) type, and the parent
19591 -- subtype of the full type must be constrained if and only if
19592 -- the ancestor subtype of the private extension is constrained.
19594 if No (Discriminant_Specifications (Parent (Priv_T)))
19595 and then not Has_Unknown_Discriminants (Priv_T)
19596 and then Has_Discriminants (Base_Type (Priv_Parent))
19599 Priv_Indic : constant Node_Id :=
19600 Subtype_Indication (Parent (Priv_T));
19602 Priv_Constr : constant Boolean :=
19603 Is_Constrained (Priv_Parent)
19605 Nkind (Priv_Indic) = N_Subtype_Indication
19607 Is_Constrained (Entity (Priv_Indic));
19609 Full_Constr : constant Boolean :=
19610 Is_Constrained (Full_Parent)
19612 Nkind (Full_Indic) = N_Subtype_Indication
19614 Is_Constrained (Entity (Full_Indic));
19616 Priv_Discr : Entity_Id;
19617 Full_Discr : Entity_Id;
19620 Priv_Discr := First_Discriminant (Priv_Parent);
19621 Full_Discr := First_Discriminant (Full_Parent);
19622 while Present (Priv_Discr) and then Present (Full_Discr) loop
19623 if Original_Record_Component (Priv_Discr) =
19624 Original_Record_Component (Full_Discr)
19626 Corresponding_Discriminant (Priv_Discr) =
19627 Corresponding_Discriminant (Full_Discr)
19634 Next_Discriminant (Priv_Discr);
19635 Next_Discriminant (Full_Discr);
19638 if Present (Priv_Discr) or else Present (Full_Discr) then
19640 ("full view must inherit discriminants of the parent"
19641 & " type used in the private extension", Full_Indic);
19643 elsif Priv_Constr and then not Full_Constr then
19645 ("parent subtype of full type must be constrained",
19648 elsif Full_Constr and then not Priv_Constr then
19650 ("parent subtype of full type must be unconstrained",
19655 -- Check the rules of 7.3(12): if a partial view has neither
19656 -- known or unknown discriminants, then the full type
19657 -- declaration shall define a definite subtype.
19659 elsif not Has_Unknown_Discriminants (Priv_T)
19660 and then not Has_Discriminants (Priv_T)
19661 and then not Is_Constrained (Full_T)
19664 ("full view must define a constrained type if partial view"
19665 & " has no discriminants", Full_T);
19668 -- ??????? Do we implement the following properly ?????
19669 -- If the ancestor subtype of a private extension has constrained
19670 -- discriminants, then the parent subtype of the full view shall
19671 -- impose a statically matching constraint on those discriminants
19676 -- For untagged types, verify that a type without discriminants is
19677 -- not completed with an unconstrained type. A separate error message
19678 -- is produced if the full type has defaulted discriminants.
19680 if Is_Definite_Subtype (Priv_T)
19681 and then not Is_Definite_Subtype (Full_T)
19683 Error_Msg_Sloc := Sloc (Parent (Priv_T));
19685 ("full view of& not compatible with declaration#",
19688 if not Is_Tagged_Type (Full_T) then
19690 ("\one is constrained, the other unconstrained", Full_T);
19695 -- AI-419: verify that the use of "limited" is consistent
19698 Orig_Decl : constant Node_Id := Original_Node (N);
19701 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19702 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
19704 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
19706 if not Limited_Present (Parent (Priv_T))
19707 and then not Synchronized_Present (Parent (Priv_T))
19708 and then Limited_Present (Type_Definition (Orig_Decl))
19711 ("full view of non-limited extension cannot be limited", N);
19713 -- Conversely, if the partial view carries the limited keyword,
19714 -- the full view must as well, even if it may be redundant.
19716 elsif Limited_Present (Parent (Priv_T))
19717 and then not Limited_Present (Type_Definition (Orig_Decl))
19720 ("full view of limited extension must be explicitly limited",
19726 -- Ada 2005 (AI-443): A synchronized private extension must be
19727 -- completed by a task or protected type.
19729 if Ada_Version >= Ada_2005
19730 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19731 and then Synchronized_Present (Parent (Priv_T))
19732 and then not Is_Concurrent_Type (Full_T)
19734 Error_Msg_N ("full view of synchronized extension must " &
19735 "be synchronized type", N);
19738 -- Ada 2005 AI-363: if the full view has discriminants with
19739 -- defaults, it is illegal to declare constrained access subtypes
19740 -- whose designated type is the current type. This allows objects
19741 -- of the type that are declared in the heap to be unconstrained.
19743 if not Has_Unknown_Discriminants (Priv_T)
19744 and then not Has_Discriminants (Priv_T)
19745 and then Has_Discriminants (Full_T)
19747 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
19749 Set_Has_Constrained_Partial_View (Full_T);
19750 Set_Has_Constrained_Partial_View (Priv_T);
19753 -- Create a full declaration for all its subtypes recorded in
19754 -- Private_Dependents and swap them similarly to the base type. These
19755 -- are subtypes that have been define before the full declaration of
19756 -- the private type. We also swap the entry in Private_Dependents list
19757 -- so we can properly restore the private view on exit from the scope.
19760 Priv_Elmt : Elmt_Id;
19761 Priv_Scop : Entity_Id;
19766 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
19767 while Present (Priv_Elmt) loop
19768 Priv := Node (Priv_Elmt);
19769 Priv_Scop := Scope (Priv);
19771 if Ekind_In (Priv, E_Private_Subtype,
19772 E_Limited_Private_Subtype,
19773 E_Record_Subtype_With_Private)
19775 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
19776 Set_Is_Itype (Full);
19777 Set_Parent (Full, Parent (Priv));
19778 Set_Associated_Node_For_Itype (Full, N);
19780 -- Now we need to complete the private subtype, but since the
19781 -- base type has already been swapped, we must also swap the
19782 -- subtypes (and thus, reverse the arguments in the call to
19783 -- Complete_Private_Subtype). Also note that we may need to
19784 -- re-establish the scope of the private subtype.
19786 Copy_And_Swap (Priv, Full);
19788 if not In_Open_Scopes (Priv_Scop) then
19789 Push_Scope (Priv_Scop);
19792 -- Reset Priv_Scop to Empty to indicate no scope was pushed
19794 Priv_Scop := Empty;
19797 Complete_Private_Subtype (Full, Priv, Full_T, N);
19799 if Present (Priv_Scop) then
19803 Replace_Elmt (Priv_Elmt, Full);
19806 Next_Elmt (Priv_Elmt);
19810 -- If the private view was tagged, copy the new primitive operations
19811 -- from the private view to the full view.
19813 if Is_Tagged_Type (Full_T) then
19815 Disp_Typ : Entity_Id;
19816 Full_List : Elist_Id;
19818 Prim_Elmt : Elmt_Id;
19819 Priv_List : Elist_Id;
19823 L : Elist_Id) return Boolean;
19824 -- Determine whether list L contains element E
19832 L : Elist_Id) return Boolean
19834 List_Elmt : Elmt_Id;
19837 List_Elmt := First_Elmt (L);
19838 while Present (List_Elmt) loop
19839 if Node (List_Elmt) = E then
19843 Next_Elmt (List_Elmt);
19849 -- Start of processing
19852 if Is_Tagged_Type (Priv_T) then
19853 Priv_List := Primitive_Operations (Priv_T);
19854 Prim_Elmt := First_Elmt (Priv_List);
19856 -- In the case of a concurrent type completing a private tagged
19857 -- type, primitives may have been declared in between the two
19858 -- views. These subprograms need to be wrapped the same way
19859 -- entries and protected procedures are handled because they
19860 -- cannot be directly shared by the two views.
19862 if Is_Concurrent_Type (Full_T) then
19864 Conc_Typ : constant Entity_Id :=
19865 Corresponding_Record_Type (Full_T);
19866 Curr_Nod : Node_Id := Parent (Conc_Typ);
19867 Wrap_Spec : Node_Id;
19870 while Present (Prim_Elmt) loop
19871 Prim := Node (Prim_Elmt);
19873 if Comes_From_Source (Prim)
19874 and then not Is_Abstract_Subprogram (Prim)
19877 Make_Subprogram_Declaration (Sloc (Prim),
19881 Obj_Typ => Conc_Typ,
19883 Parameter_Specifications (
19886 Insert_After (Curr_Nod, Wrap_Spec);
19887 Curr_Nod := Wrap_Spec;
19889 Analyze (Wrap_Spec);
19892 Next_Elmt (Prim_Elmt);
19898 -- For non-concurrent types, transfer explicit primitives, but
19899 -- omit those inherited from the parent of the private view
19900 -- since they will be re-inherited later on.
19903 Full_List := Primitive_Operations (Full_T);
19905 while Present (Prim_Elmt) loop
19906 Prim := Node (Prim_Elmt);
19908 if Comes_From_Source (Prim)
19909 and then not Contains (Prim, Full_List)
19911 Append_Elmt (Prim, Full_List);
19914 Next_Elmt (Prim_Elmt);
19918 -- Untagged private view
19921 Full_List := Primitive_Operations (Full_T);
19923 -- In this case the partial view is untagged, so here we locate
19924 -- all of the earlier primitives that need to be treated as
19925 -- dispatching (those that appear between the two views). Note
19926 -- that these additional operations must all be new operations
19927 -- (any earlier operations that override inherited operations
19928 -- of the full view will already have been inserted in the
19929 -- primitives list, marked by Check_Operation_From_Private_View
19930 -- as dispatching. Note that implicit "/=" operators are
19931 -- excluded from being added to the primitives list since they
19932 -- shouldn't be treated as dispatching (tagged "/=" is handled
19935 Prim := Next_Entity (Full_T);
19936 while Present (Prim) and then Prim /= Priv_T loop
19937 if Ekind_In (Prim, E_Procedure, E_Function) then
19938 Disp_Typ := Find_Dispatching_Type (Prim);
19940 if Disp_Typ = Full_T
19941 and then (Chars (Prim) /= Name_Op_Ne
19942 or else Comes_From_Source (Prim))
19944 Check_Controlling_Formals (Full_T, Prim);
19946 if not Is_Dispatching_Operation (Prim) then
19947 Append_Elmt (Prim, Full_List);
19948 Set_Is_Dispatching_Operation (Prim, True);
19949 Set_DT_Position_Value (Prim, No_Uint);
19952 elsif Is_Dispatching_Operation (Prim)
19953 and then Disp_Typ /= Full_T
19956 -- Verify that it is not otherwise controlled by a
19957 -- formal or a return value of type T.
19959 Check_Controlling_Formals (Disp_Typ, Prim);
19963 Next_Entity (Prim);
19967 -- For the tagged case, the two views can share the same primitive
19968 -- operations list and the same class-wide type. Update attributes
19969 -- of the class-wide type which depend on the full declaration.
19971 if Is_Tagged_Type (Priv_T) then
19972 Set_Direct_Primitive_Operations (Priv_T, Full_List);
19973 Set_Class_Wide_Type
19974 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
19976 Set_Has_Task (Class_Wide_Type (Priv_T), Has_Task (Full_T));
19978 (Class_Wide_Type (Priv_T), Has_Protected (Full_T));
19983 -- Ada 2005 AI 161: Check preelaborable initialization consistency
19985 if Known_To_Have_Preelab_Init (Priv_T) then
19987 -- Case where there is a pragma Preelaborable_Initialization. We
19988 -- always allow this in predefined units, which is cheating a bit,
19989 -- but it means we don't have to struggle to meet the requirements in
19990 -- the RM for having Preelaborable Initialization. Otherwise we
19991 -- require that the type meets the RM rules. But we can't check that
19992 -- yet, because of the rule about overriding Initialize, so we simply
19993 -- set a flag that will be checked at freeze time.
19995 if not In_Predefined_Unit (Full_T) then
19996 Set_Must_Have_Preelab_Init (Full_T);
20000 -- If pragma CPP_Class was applied to the private type declaration,
20001 -- propagate it now to the full type declaration.
20003 if Is_CPP_Class (Priv_T) then
20004 Set_Is_CPP_Class (Full_T);
20005 Set_Convention (Full_T, Convention_CPP);
20007 -- Check that components of imported CPP types do not have default
20010 Check_CPP_Type_Has_No_Defaults (Full_T);
20013 -- If the private view has user specified stream attributes, then so has
20016 -- Why the test, how could these flags be already set in Full_T ???
20018 if Has_Specified_Stream_Read (Priv_T) then
20019 Set_Has_Specified_Stream_Read (Full_T);
20022 if Has_Specified_Stream_Write (Priv_T) then
20023 Set_Has_Specified_Stream_Write (Full_T);
20026 if Has_Specified_Stream_Input (Priv_T) then
20027 Set_Has_Specified_Stream_Input (Full_T);
20030 if Has_Specified_Stream_Output (Priv_T) then
20031 Set_Has_Specified_Stream_Output (Full_T);
20034 -- Propagate the attributes related to pragma Default_Initial_Condition
20035 -- from the private to the full view. Note that both flags are mutually
20038 if Has_Default_Init_Cond (Priv_T)
20039 or else Has_Inherited_Default_Init_Cond (Priv_T)
20041 Propagate_Default_Init_Cond_Attributes
20042 (From_Typ => Priv_T,
20044 Private_To_Full_View => True);
20046 -- In the case where the full view is derived from another private type,
20047 -- the attributes related to pragma Default_Initial_Condition must be
20048 -- propagated from the full to the private view to maintain consistency
20052 -- type Parent_Typ is private
20053 -- with Default_Initial_Condition ...;
20055 -- type Parent_Typ is ...;
20058 -- with Pack; use Pack;
20059 -- package Pack_2 is
20060 -- type Deriv_Typ is private; -- must inherit
20062 -- type Deriv_Typ is new Parent_Typ; -- must inherit
20065 elsif Has_Default_Init_Cond (Full_T)
20066 or else Has_Inherited_Default_Init_Cond (Full_T)
20068 Propagate_Default_Init_Cond_Attributes
20069 (From_Typ => Full_T,
20071 Private_To_Full_View => True);
20074 if Is_Ghost_Entity (Priv_T) then
20076 -- The Ghost policy in effect at the point of declaration and at the
20077 -- point of completion must match (SPARK RM 6.9(14)).
20079 Check_Ghost_Completion (Priv_T, Full_T);
20081 -- In the case where the private view of a tagged type lacks a parent
20082 -- type and is subject to pragma Ghost, ensure that the parent type
20083 -- specified by the full view is also Ghost (SPARK RM 6.9(9)).
20085 if Is_Derived_Type (Full_T) then
20086 Check_Ghost_Derivation (Full_T);
20089 -- Propagate the attributes related to pragma Ghost from the private
20090 -- to the full view.
20092 Mark_Full_View_As_Ghost (Priv_T, Full_T);
20095 -- Propagate invariants to full type
20097 if Has_Invariants (Priv_T) then
20098 Set_Has_Invariants (Full_T);
20099 Set_Invariant_Procedure (Full_T, Invariant_Procedure (Priv_T));
20102 if Has_Inheritable_Invariants (Priv_T) then
20103 Set_Has_Inheritable_Invariants (Full_T);
20106 -- Check hidden inheritance of class-wide type invariants
20108 if Ada_Version >= Ada_2012
20109 and then not Has_Inheritable_Invariants (Full_T)
20110 and then In_Private_Part (Current_Scope)
20111 and then Has_Interfaces (Full_T)
20118 Collect_Interfaces (Full_T, Ifaces, Exclude_Parents => True);
20120 AI := First_Elmt (Ifaces);
20121 while Present (AI) loop
20122 if Has_Inheritable_Invariants (Node (AI)) then
20124 ("hidden inheritance of class-wide type invariants " &
20134 -- Propagate predicates to full type, and predicate function if already
20135 -- defined. It is not clear that this can actually happen? the partial
20136 -- view cannot be frozen yet, and the predicate function has not been
20137 -- built. Still it is a cheap check and seems safer to make it.
20139 if Has_Predicates (Priv_T) then
20140 if Present (Predicate_Function (Priv_T)) then
20141 Set_Predicate_Function (Full_T, Predicate_Function (Priv_T));
20144 Set_Has_Predicates (Full_T);
20146 end Process_Full_View;
20148 -----------------------------------
20149 -- Process_Incomplete_Dependents --
20150 -----------------------------------
20152 procedure Process_Incomplete_Dependents
20154 Full_T : Entity_Id;
20157 Inc_Elmt : Elmt_Id;
20158 Priv_Dep : Entity_Id;
20159 New_Subt : Entity_Id;
20161 Disc_Constraint : Elist_Id;
20164 if No (Private_Dependents (Inc_T)) then
20168 -- Itypes that may be generated by the completion of an incomplete
20169 -- subtype are not used by the back-end and not attached to the tree.
20170 -- They are created only for constraint-checking purposes.
20172 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
20173 while Present (Inc_Elmt) loop
20174 Priv_Dep := Node (Inc_Elmt);
20176 if Ekind (Priv_Dep) = E_Subprogram_Type then
20178 -- An Access_To_Subprogram type may have a return type or a
20179 -- parameter type that is incomplete. Replace with the full view.
20181 if Etype (Priv_Dep) = Inc_T then
20182 Set_Etype (Priv_Dep, Full_T);
20186 Formal : Entity_Id;
20189 Formal := First_Formal (Priv_Dep);
20190 while Present (Formal) loop
20191 if Etype (Formal) = Inc_T then
20192 Set_Etype (Formal, Full_T);
20195 Next_Formal (Formal);
20199 elsif Is_Overloadable (Priv_Dep) then
20201 -- If a subprogram in the incomplete dependents list is primitive
20202 -- for a tagged full type then mark it as a dispatching operation,
20203 -- check whether it overrides an inherited subprogram, and check
20204 -- restrictions on its controlling formals. Note that a protected
20205 -- operation is never dispatching: only its wrapper operation
20206 -- (which has convention Ada) is.
20208 if Is_Tagged_Type (Full_T)
20209 and then Is_Primitive (Priv_Dep)
20210 and then Convention (Priv_Dep) /= Convention_Protected
20212 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
20213 Set_Is_Dispatching_Operation (Priv_Dep);
20214 Check_Controlling_Formals (Full_T, Priv_Dep);
20217 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
20219 -- Can happen during processing of a body before the completion
20220 -- of a TA type. Ignore, because spec is also on dependent list.
20224 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
20225 -- corresponding subtype of the full view.
20227 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype then
20228 Set_Subtype_Indication
20229 (Parent (Priv_Dep), New_Occurrence_Of (Full_T, Sloc (Priv_Dep)));
20230 Set_Etype (Priv_Dep, Full_T);
20231 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
20232 Set_Analyzed (Parent (Priv_Dep), False);
20234 -- Reanalyze the declaration, suppressing the call to
20235 -- Enter_Name to avoid duplicate names.
20237 Analyze_Subtype_Declaration
20238 (N => Parent (Priv_Dep),
20241 -- Dependent is a subtype
20244 -- We build a new subtype indication using the full view of the
20245 -- incomplete parent. The discriminant constraints have been
20246 -- elaborated already at the point of the subtype declaration.
20248 New_Subt := Create_Itype (E_Void, N);
20250 if Has_Discriminants (Full_T) then
20251 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
20253 Disc_Constraint := No_Elist;
20256 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
20257 Set_Full_View (Priv_Dep, New_Subt);
20260 Next_Elmt (Inc_Elmt);
20262 end Process_Incomplete_Dependents;
20264 --------------------------------
20265 -- Process_Range_Expr_In_Decl --
20266 --------------------------------
20268 procedure Process_Range_Expr_In_Decl
20271 Subtyp : Entity_Id := Empty;
20272 Check_List : List_Id := Empty_List;
20273 R_Check_Off : Boolean := False;
20274 In_Iter_Schm : Boolean := False)
20277 R_Checks : Check_Result;
20278 Insert_Node : Node_Id;
20279 Def_Id : Entity_Id;
20282 Analyze_And_Resolve (R, Base_Type (T));
20284 if Nkind (R) = N_Range then
20286 -- In SPARK, all ranges should be static, with the exception of the
20287 -- discrete type definition of a loop parameter specification.
20289 if not In_Iter_Schm
20290 and then not Is_OK_Static_Range (R)
20292 Check_SPARK_05_Restriction ("range should be static", R);
20295 Lo := Low_Bound (R);
20296 Hi := High_Bound (R);
20298 -- Validity checks on the range of a quantified expression are
20299 -- delayed until the construct is transformed into a loop.
20301 if Nkind (Parent (R)) = N_Loop_Parameter_Specification
20302 and then Nkind (Parent (Parent (R))) = N_Quantified_Expression
20306 -- We need to ensure validity of the bounds here, because if we
20307 -- go ahead and do the expansion, then the expanded code will get
20308 -- analyzed with range checks suppressed and we miss the check.
20310 -- WARNING: The capture of the range bounds with xxx_FIRST/_LAST and
20311 -- the temporaries generated by routine Remove_Side_Effects by means
20312 -- of validity checks must use the same names. When a range appears
20313 -- in the parent of a generic, the range is processed with checks
20314 -- disabled as part of the generic context and with checks enabled
20315 -- for code generation purposes. This leads to link issues as the
20316 -- generic contains references to xxx_FIRST/_LAST, but the inlined
20317 -- template sees the temporaries generated by Remove_Side_Effects.
20320 Validity_Check_Range (R, Subtyp);
20323 -- If there were errors in the declaration, try and patch up some
20324 -- common mistakes in the bounds. The cases handled are literals
20325 -- which are Integer where the expected type is Real and vice versa.
20326 -- These corrections allow the compilation process to proceed further
20327 -- along since some basic assumptions of the format of the bounds
20330 if Etype (R) = Any_Type then
20331 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
20333 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
20335 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
20337 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
20339 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
20341 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
20343 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
20345 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
20352 -- If the bounds of the range have been mistakenly given as string
20353 -- literals (perhaps in place of character literals), then an error
20354 -- has already been reported, but we rewrite the string literal as a
20355 -- bound of the range's type to avoid blowups in later processing
20356 -- that looks at static values.
20358 if Nkind (Lo) = N_String_Literal then
20360 Make_Attribute_Reference (Sloc (Lo),
20361 Prefix => New_Occurrence_Of (T, Sloc (Lo)),
20362 Attribute_Name => Name_First));
20363 Analyze_And_Resolve (Lo);
20366 if Nkind (Hi) = N_String_Literal then
20368 Make_Attribute_Reference (Sloc (Hi),
20369 Prefix => New_Occurrence_Of (T, Sloc (Hi)),
20370 Attribute_Name => Name_First));
20371 Analyze_And_Resolve (Hi);
20374 -- If bounds aren't scalar at this point then exit, avoiding
20375 -- problems with further processing of the range in this procedure.
20377 if not Is_Scalar_Type (Etype (Lo)) then
20381 -- Resolve (actually Sem_Eval) has checked that the bounds are in
20382 -- then range of the base type. Here we check whether the bounds
20383 -- are in the range of the subtype itself. Note that if the bounds
20384 -- represent the null range the Constraint_Error exception should
20387 -- ??? The following code should be cleaned up as follows
20389 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
20390 -- is done in the call to Range_Check (R, T); below
20392 -- 2. The use of R_Check_Off should be investigated and possibly
20393 -- removed, this would clean up things a bit.
20395 if Is_Null_Range (Lo, Hi) then
20399 -- Capture values of bounds and generate temporaries for them
20400 -- if needed, before applying checks, since checks may cause
20401 -- duplication of the expression without forcing evaluation.
20403 -- The forced evaluation removes side effects from expressions,
20404 -- which should occur also in GNATprove mode. Otherwise, we end up
20405 -- with unexpected insertions of actions at places where this is
20406 -- not supposed to occur, e.g. on default parameters of a call.
20408 if Expander_Active or GNATprove_Mode then
20410 -- Call Force_Evaluation to create declarations as needed to
20411 -- deal with side effects, and also create typ_FIRST/LAST
20412 -- entities for bounds if we have a subtype name.
20414 -- Note: we do this transformation even if expansion is not
20415 -- active if we are in GNATprove_Mode since the transformation
20416 -- is in general required to ensure that the resulting tree has
20417 -- proper Ada semantics.
20420 (Lo, Related_Id => Subtyp, Is_Low_Bound => True);
20422 (Hi, Related_Id => Subtyp, Is_High_Bound => True);
20425 -- We use a flag here instead of suppressing checks on the type
20426 -- because the type we check against isn't necessarily the place
20427 -- where we put the check.
20429 if not R_Check_Off then
20430 R_Checks := Get_Range_Checks (R, T);
20432 -- Look up tree to find an appropriate insertion point. We
20433 -- can't just use insert_actions because later processing
20434 -- depends on the insertion node. Prior to Ada 2012 the
20435 -- insertion point could only be a declaration or a loop, but
20436 -- quantified expressions can appear within any context in an
20437 -- expression, and the insertion point can be any statement,
20438 -- pragma, or declaration.
20440 Insert_Node := Parent (R);
20441 while Present (Insert_Node) loop
20443 Nkind (Insert_Node) in N_Declaration
20446 (Insert_Node, N_Component_Declaration,
20447 N_Loop_Parameter_Specification,
20448 N_Function_Specification,
20449 N_Procedure_Specification);
20451 exit when Nkind (Insert_Node) in N_Later_Decl_Item
20452 or else Nkind (Insert_Node) in
20453 N_Statement_Other_Than_Procedure_Call
20454 or else Nkind_In (Insert_Node, N_Procedure_Call_Statement,
20457 Insert_Node := Parent (Insert_Node);
20460 -- Why would Type_Decl not be present??? Without this test,
20461 -- short regression tests fail.
20463 if Present (Insert_Node) then
20465 -- Case of loop statement. Verify that the range is part
20466 -- of the subtype indication of the iteration scheme.
20468 if Nkind (Insert_Node) = N_Loop_Statement then
20473 Indic := Parent (R);
20474 while Present (Indic)
20475 and then Nkind (Indic) /= N_Subtype_Indication
20477 Indic := Parent (Indic);
20480 if Present (Indic) then
20481 Def_Id := Etype (Subtype_Mark (Indic));
20483 Insert_Range_Checks
20487 Sloc (Insert_Node),
20489 Do_Before => True);
20493 -- Insertion before a declaration. If the declaration
20494 -- includes discriminants, the list of applicable checks
20495 -- is given by the caller.
20497 elsif Nkind (Insert_Node) in N_Declaration then
20498 Def_Id := Defining_Identifier (Insert_Node);
20500 if (Ekind (Def_Id) = E_Record_Type
20501 and then Depends_On_Discriminant (R))
20503 (Ekind (Def_Id) = E_Protected_Type
20504 and then Has_Discriminants (Def_Id))
20506 Append_Range_Checks
20508 Check_List, Def_Id, Sloc (Insert_Node), R);
20511 Insert_Range_Checks
20513 Insert_Node, Def_Id, Sloc (Insert_Node), R);
20517 -- Insertion before a statement. Range appears in the
20518 -- context of a quantified expression. Insertion will
20519 -- take place when expression is expanded.
20528 -- Case of other than an explicit N_Range node
20530 -- The forced evaluation removes side effects from expressions, which
20531 -- should occur also in GNATprove mode. Otherwise, we end up with
20532 -- unexpected insertions of actions at places where this is not
20533 -- supposed to occur, e.g. on default parameters of a call.
20535 elsif Expander_Active or GNATprove_Mode then
20536 Get_Index_Bounds (R, Lo, Hi);
20537 Force_Evaluation (Lo);
20538 Force_Evaluation (Hi);
20540 end Process_Range_Expr_In_Decl;
20542 --------------------------------------
20543 -- Process_Real_Range_Specification --
20544 --------------------------------------
20546 procedure Process_Real_Range_Specification (Def : Node_Id) is
20547 Spec : constant Node_Id := Real_Range_Specification (Def);
20550 Err : Boolean := False;
20552 procedure Analyze_Bound (N : Node_Id);
20553 -- Analyze and check one bound
20555 -------------------
20556 -- Analyze_Bound --
20557 -------------------
20559 procedure Analyze_Bound (N : Node_Id) is
20561 Analyze_And_Resolve (N, Any_Real);
20563 if not Is_OK_Static_Expression (N) then
20564 Flag_Non_Static_Expr
20565 ("bound in real type definition is not static!", N);
20570 -- Start of processing for Process_Real_Range_Specification
20573 if Present (Spec) then
20574 Lo := Low_Bound (Spec);
20575 Hi := High_Bound (Spec);
20576 Analyze_Bound (Lo);
20577 Analyze_Bound (Hi);
20579 -- If error, clear away junk range specification
20582 Set_Real_Range_Specification (Def, Empty);
20585 end Process_Real_Range_Specification;
20587 ---------------------
20588 -- Process_Subtype --
20589 ---------------------
20591 function Process_Subtype
20593 Related_Nod : Node_Id;
20594 Related_Id : Entity_Id := Empty;
20595 Suffix : Character := ' ') return Entity_Id
20598 Def_Id : Entity_Id;
20599 Error_Node : Node_Id;
20600 Full_View_Id : Entity_Id;
20601 Subtype_Mark_Id : Entity_Id;
20603 May_Have_Null_Exclusion : Boolean;
20605 procedure Check_Incomplete (T : Entity_Id);
20606 -- Called to verify that an incomplete type is not used prematurely
20608 ----------------------
20609 -- Check_Incomplete --
20610 ----------------------
20612 procedure Check_Incomplete (T : Entity_Id) is
20614 -- Ada 2005 (AI-412): Incomplete subtypes are legal
20616 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
20618 not (Ada_Version >= Ada_2005
20620 (Nkind (Parent (T)) = N_Subtype_Declaration
20621 or else (Nkind (Parent (T)) = N_Subtype_Indication
20622 and then Nkind (Parent (Parent (T))) =
20623 N_Subtype_Declaration)))
20625 Error_Msg_N ("invalid use of type before its full declaration", T);
20627 end Check_Incomplete;
20629 -- Start of processing for Process_Subtype
20632 -- Case of no constraints present
20634 if Nkind (S) /= N_Subtype_Indication then
20636 Check_Incomplete (S);
20639 -- Ada 2005 (AI-231): Static check
20641 if Ada_Version >= Ada_2005
20642 and then Present (P)
20643 and then Null_Exclusion_Present (P)
20644 and then Nkind (P) /= N_Access_To_Object_Definition
20645 and then not Is_Access_Type (Entity (S))
20647 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
20650 -- The following is ugly, can't we have a range or even a flag???
20652 May_Have_Null_Exclusion :=
20653 Nkind_In (P, N_Access_Definition,
20654 N_Access_Function_Definition,
20655 N_Access_Procedure_Definition,
20656 N_Access_To_Object_Definition,
20658 N_Component_Definition)
20660 Nkind_In (P, N_Derived_Type_Definition,
20661 N_Discriminant_Specification,
20662 N_Formal_Object_Declaration,
20663 N_Object_Declaration,
20664 N_Object_Renaming_Declaration,
20665 N_Parameter_Specification,
20666 N_Subtype_Declaration);
20668 -- Create an Itype that is a duplicate of Entity (S) but with the
20669 -- null-exclusion attribute.
20671 if May_Have_Null_Exclusion
20672 and then Is_Access_Type (Entity (S))
20673 and then Null_Exclusion_Present (P)
20675 -- No need to check the case of an access to object definition.
20676 -- It is correct to define double not-null pointers.
20679 -- type Not_Null_Int_Ptr is not null access Integer;
20680 -- type Acc is not null access Not_Null_Int_Ptr;
20682 and then Nkind (P) /= N_Access_To_Object_Definition
20684 if Can_Never_Be_Null (Entity (S)) then
20685 case Nkind (Related_Nod) is
20686 when N_Full_Type_Declaration =>
20687 if Nkind (Type_Definition (Related_Nod))
20688 in N_Array_Type_Definition
20692 (Component_Definition
20693 (Type_Definition (Related_Nod)));
20696 Subtype_Indication (Type_Definition (Related_Nod));
20699 when N_Subtype_Declaration =>
20700 Error_Node := Subtype_Indication (Related_Nod);
20702 when N_Object_Declaration =>
20703 Error_Node := Object_Definition (Related_Nod);
20705 when N_Component_Declaration =>
20707 Subtype_Indication (Component_Definition (Related_Nod));
20709 when N_Allocator =>
20710 Error_Node := Expression (Related_Nod);
20713 pragma Assert (False);
20714 Error_Node := Related_Nod;
20718 ("`NOT NULL` not allowed (& already excludes null)",
20724 Create_Null_Excluding_Itype
20726 Related_Nod => P));
20727 Set_Entity (S, Etype (S));
20732 -- Case of constraint present, so that we have an N_Subtype_Indication
20733 -- node (this node is created only if constraints are present).
20736 Find_Type (Subtype_Mark (S));
20738 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
20740 (Nkind (Parent (S)) = N_Subtype_Declaration
20741 and then Is_Itype (Defining_Identifier (Parent (S))))
20743 Check_Incomplete (Subtype_Mark (S));
20747 Subtype_Mark_Id := Entity (Subtype_Mark (S));
20749 -- Explicit subtype declaration case
20751 if Nkind (P) = N_Subtype_Declaration then
20752 Def_Id := Defining_Identifier (P);
20754 -- Explicit derived type definition case
20756 elsif Nkind (P) = N_Derived_Type_Definition then
20757 Def_Id := Defining_Identifier (Parent (P));
20759 -- Implicit case, the Def_Id must be created as an implicit type.
20760 -- The one exception arises in the case of concurrent types, array
20761 -- and access types, where other subsidiary implicit types may be
20762 -- created and must appear before the main implicit type. In these
20763 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
20764 -- has not yet been called to create Def_Id.
20767 if Is_Array_Type (Subtype_Mark_Id)
20768 or else Is_Concurrent_Type (Subtype_Mark_Id)
20769 or else Is_Access_Type (Subtype_Mark_Id)
20773 -- For the other cases, we create a new unattached Itype,
20774 -- and set the indication to ensure it gets attached later.
20778 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
20782 -- If the kind of constraint is invalid for this kind of type,
20783 -- then give an error, and then pretend no constraint was given.
20785 if not Is_Valid_Constraint_Kind
20786 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
20789 ("incorrect constraint for this kind of type", Constraint (S));
20791 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
20793 -- Set Ekind of orphan itype, to prevent cascaded errors
20795 if Present (Def_Id) then
20796 Set_Ekind (Def_Id, Ekind (Any_Type));
20799 -- Make recursive call, having got rid of the bogus constraint
20801 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
20804 -- Remaining processing depends on type. Select on Base_Type kind to
20805 -- ensure getting to the concrete type kind in the case of a private
20806 -- subtype (needed when only doing semantic analysis).
20808 case Ekind (Base_Type (Subtype_Mark_Id)) is
20809 when Access_Kind =>
20811 -- If this is a constraint on a class-wide type, discard it.
20812 -- There is currently no way to express a partial discriminant
20813 -- constraint on a type with unknown discriminants. This is
20814 -- a pathology that the ACATS wisely decides not to test.
20816 if Is_Class_Wide_Type (Designated_Type (Subtype_Mark_Id)) then
20817 if Comes_From_Source (S) then
20819 ("constraint on class-wide type ignored??",
20823 if Nkind (P) = N_Subtype_Declaration then
20824 Set_Subtype_Indication (P,
20825 New_Occurrence_Of (Subtype_Mark_Id, Sloc (S)));
20828 return Subtype_Mark_Id;
20831 Constrain_Access (Def_Id, S, Related_Nod);
20834 and then Is_Itype (Designated_Type (Def_Id))
20835 and then Nkind (Related_Nod) = N_Subtype_Declaration
20836 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
20838 Build_Itype_Reference
20839 (Designated_Type (Def_Id), Related_Nod);
20843 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
20845 when Decimal_Fixed_Point_Kind =>
20846 Constrain_Decimal (Def_Id, S);
20848 when Enumeration_Kind =>
20849 Constrain_Enumeration (Def_Id, S);
20850 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
20852 when Ordinary_Fixed_Point_Kind =>
20853 Constrain_Ordinary_Fixed (Def_Id, S);
20856 Constrain_Float (Def_Id, S);
20858 when Integer_Kind =>
20859 Constrain_Integer (Def_Id, S);
20860 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
20862 when E_Record_Type |
20865 E_Incomplete_Type =>
20866 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
20868 if Ekind (Def_Id) = E_Incomplete_Type then
20869 Set_Private_Dependents (Def_Id, New_Elmt_List);
20872 when Private_Kind =>
20873 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
20874 Set_Private_Dependents (Def_Id, New_Elmt_List);
20876 -- In case of an invalid constraint prevent further processing
20877 -- since the type constructed is missing expected fields.
20879 if Etype (Def_Id) = Any_Type then
20883 -- If the full view is that of a task with discriminants,
20884 -- we must constrain both the concurrent type and its
20885 -- corresponding record type. Otherwise we will just propagate
20886 -- the constraint to the full view, if available.
20888 if Present (Full_View (Subtype_Mark_Id))
20889 and then Has_Discriminants (Subtype_Mark_Id)
20890 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
20893 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
20895 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
20896 Constrain_Concurrent (Full_View_Id, S,
20897 Related_Nod, Related_Id, Suffix);
20898 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
20899 Set_Full_View (Def_Id, Full_View_Id);
20901 -- Introduce an explicit reference to the private subtype,
20902 -- to prevent scope anomalies in gigi if first use appears
20903 -- in a nested context, e.g. a later function body.
20904 -- Should this be generated in other contexts than a full
20905 -- type declaration?
20907 if Is_Itype (Def_Id)
20909 Nkind (Parent (P)) = N_Full_Type_Declaration
20911 Build_Itype_Reference (Def_Id, Parent (P));
20915 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
20918 when Concurrent_Kind =>
20919 Constrain_Concurrent (Def_Id, S,
20920 Related_Nod, Related_Id, Suffix);
20923 Error_Msg_N ("invalid subtype mark in subtype indication", S);
20926 -- Size and Convention are always inherited from the base type
20928 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
20929 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
20933 end Process_Subtype;
20935 --------------------------------------------
20936 -- Propagate_Default_Init_Cond_Attributes --
20937 --------------------------------------------
20939 procedure Propagate_Default_Init_Cond_Attributes
20940 (From_Typ : Entity_Id;
20941 To_Typ : Entity_Id;
20942 Parent_To_Derivation : Boolean := False;
20943 Private_To_Full_View : Boolean := False)
20945 procedure Remove_Default_Init_Cond_Procedure (Typ : Entity_Id);
20946 -- Remove the default initial procedure (if any) from the rep chain of
20949 ----------------------------------------
20950 -- Remove_Default_Init_Cond_Procedure --
20951 ----------------------------------------
20953 procedure Remove_Default_Init_Cond_Procedure (Typ : Entity_Id) is
20954 Found : Boolean := False;
20960 Subp := Subprograms_For_Type (Typ);
20961 while Present (Subp) loop
20962 if Is_Default_Init_Cond_Procedure (Subp) then
20968 Subp := Subprograms_For_Type (Subp);
20972 Set_Subprograms_For_Type (Prev, Subprograms_For_Type (Subp));
20973 Set_Subprograms_For_Type (Subp, Empty);
20975 end Remove_Default_Init_Cond_Procedure;
20979 Inherit_Procedure : Boolean := False;
20981 -- Start of processing for Propagate_Default_Init_Cond_Attributes
20984 if Has_Default_Init_Cond (From_Typ) then
20986 -- A derived type inherits the attributes from its parent type
20988 if Parent_To_Derivation then
20989 Set_Has_Inherited_Default_Init_Cond (To_Typ);
20991 -- A full view shares the attributes with its private view
20994 Set_Has_Default_Init_Cond (To_Typ);
20997 Inherit_Procedure := True;
20999 -- Due to the order of expansion, a derived private type is processed
21000 -- by two routines which both attempt to set the attributes related
21001 -- to pragma Default_Initial_Condition - Build_Derived_Type and then
21002 -- Process_Full_View.
21005 -- type Parent_Typ is private
21006 -- with Default_Initial_Condition ...;
21008 -- type Parent_Typ is ...;
21011 -- with Pack; use Pack;
21012 -- package Pack_2 is
21013 -- type Deriv_Typ is private
21014 -- with Default_Initial_Condition ...;
21016 -- type Deriv_Typ is new Parent_Typ;
21019 -- When Build_Derived_Type operates, it sets the attributes on the
21020 -- full view without taking into account that the private view may
21021 -- define its own default initial condition procedure. This becomes
21022 -- apparent in Process_Full_View which must undo some of the work by
21023 -- Build_Derived_Type and propagate the attributes from the private
21024 -- to the full view.
21026 if Private_To_Full_View then
21027 Set_Has_Inherited_Default_Init_Cond (To_Typ, False);
21028 Remove_Default_Init_Cond_Procedure (To_Typ);
21031 -- A type must inherit the default initial condition procedure from a
21032 -- parent type when the parent itself is inheriting the procedure or
21033 -- when it is defining one. This circuitry is also used when dealing
21034 -- with the private / full view of a type.
21036 elsif Has_Inherited_Default_Init_Cond (From_Typ)
21037 or (Parent_To_Derivation
21038 and Present (Get_Pragma
21039 (From_Typ, Pragma_Default_Initial_Condition)))
21041 Set_Has_Inherited_Default_Init_Cond (To_Typ);
21042 Inherit_Procedure := True;
21045 if Inherit_Procedure
21046 and then No (Default_Init_Cond_Procedure (To_Typ))
21048 Set_Default_Init_Cond_Procedure
21049 (To_Typ, Default_Init_Cond_Procedure (From_Typ));
21051 end Propagate_Default_Init_Cond_Attributes;
21053 -----------------------------
21054 -- Record_Type_Declaration --
21055 -----------------------------
21057 procedure Record_Type_Declaration
21062 Def : constant Node_Id := Type_Definition (N);
21063 Is_Tagged : Boolean;
21064 Tag_Comp : Entity_Id;
21067 -- These flags must be initialized before calling Process_Discriminants
21068 -- because this routine makes use of them.
21070 Set_Ekind (T, E_Record_Type);
21072 Init_Size_Align (T);
21073 Set_Interfaces (T, No_Elist);
21074 Set_Stored_Constraint (T, No_Elist);
21075 Set_Default_SSO (T);
21079 if Ada_Version < Ada_2005 or else not Interface_Present (Def) then
21080 if Limited_Present (Def) then
21081 Check_SPARK_05_Restriction ("limited is not allowed", N);
21084 if Abstract_Present (Def) then
21085 Check_SPARK_05_Restriction ("abstract is not allowed", N);
21088 -- The flag Is_Tagged_Type might have already been set by
21089 -- Find_Type_Name if it detected an error for declaration T. This
21090 -- arises in the case of private tagged types where the full view
21091 -- omits the word tagged.
21094 Tagged_Present (Def)
21095 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
21097 Set_Is_Limited_Record (T, Limited_Present (Def));
21100 Set_Is_Tagged_Type (T, True);
21101 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
21104 -- Type is abstract if full declaration carries keyword, or if
21105 -- previous partial view did.
21107 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
21108 or else Abstract_Present (Def));
21111 Check_SPARK_05_Restriction ("interface is not allowed", N);
21114 Analyze_Interface_Declaration (T, Def);
21116 if Present (Discriminant_Specifications (N)) then
21118 ("interface types cannot have discriminants",
21119 Defining_Identifier
21120 (First (Discriminant_Specifications (N))));
21124 -- First pass: if there are self-referential access components,
21125 -- create the required anonymous access type declarations, and if
21126 -- need be an incomplete type declaration for T itself.
21128 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
21130 if Ada_Version >= Ada_2005
21131 and then Present (Interface_List (Def))
21133 Check_Interfaces (N, Def);
21136 Ifaces_List : Elist_Id;
21139 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
21140 -- already in the parents.
21144 Ifaces_List => Ifaces_List,
21145 Exclude_Parents => True);
21147 Set_Interfaces (T, Ifaces_List);
21151 -- Records constitute a scope for the component declarations within.
21152 -- The scope is created prior to the processing of these declarations.
21153 -- Discriminants are processed first, so that they are visible when
21154 -- processing the other components. The Ekind of the record type itself
21155 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
21157 -- Enter record scope
21161 -- If an incomplete or private type declaration was already given for
21162 -- the type, then this scope already exists, and the discriminants have
21163 -- been declared within. We must verify that the full declaration
21164 -- matches the incomplete one.
21166 Check_Or_Process_Discriminants (N, T, Prev);
21168 Set_Is_Constrained (T, not Has_Discriminants (T));
21169 Set_Has_Delayed_Freeze (T, True);
21171 -- For tagged types add a manually analyzed component corresponding
21172 -- to the component _tag, the corresponding piece of tree will be
21173 -- expanded as part of the freezing actions if it is not a CPP_Class.
21177 -- Do not add the tag unless we are in expansion mode
21179 if Expander_Active then
21180 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
21181 Enter_Name (Tag_Comp);
21183 Set_Ekind (Tag_Comp, E_Component);
21184 Set_Is_Tag (Tag_Comp);
21185 Set_Is_Aliased (Tag_Comp);
21186 Set_Etype (Tag_Comp, RTE (RE_Tag));
21187 Set_DT_Entry_Count (Tag_Comp, No_Uint);
21188 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
21189 Init_Component_Location (Tag_Comp);
21191 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
21192 -- implemented interfaces.
21194 if Has_Interfaces (T) then
21195 Add_Interface_Tag_Components (N, T);
21199 Make_Class_Wide_Type (T);
21200 Set_Direct_Primitive_Operations (T, New_Elmt_List);
21203 -- We must suppress range checks when processing record components in
21204 -- the presence of discriminants, since we don't want spurious checks to
21205 -- be generated during their analysis, but Suppress_Range_Checks flags
21206 -- must be reset the after processing the record definition.
21208 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
21209 -- couldn't we just use the normal range check suppression method here.
21210 -- That would seem cleaner ???
21212 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
21213 Set_Kill_Range_Checks (T, True);
21214 Record_Type_Definition (Def, Prev);
21215 Set_Kill_Range_Checks (T, False);
21217 Record_Type_Definition (Def, Prev);
21220 -- Exit from record scope
21224 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
21225 -- the implemented interfaces and associate them an aliased entity.
21228 and then not Is_Empty_List (Interface_List (Def))
21230 Derive_Progenitor_Subprograms (T, T);
21233 Check_Function_Writable_Actuals (N);
21234 end Record_Type_Declaration;
21236 ----------------------------
21237 -- Record_Type_Definition --
21238 ----------------------------
21240 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
21241 Component : Entity_Id;
21242 Ctrl_Components : Boolean := False;
21243 Final_Storage_Only : Boolean;
21247 if Ekind (Prev_T) = E_Incomplete_Type then
21248 T := Full_View (Prev_T);
21253 -- In SPARK, tagged types and type extensions may only be declared in
21254 -- the specification of library unit packages.
21256 if Present (Def) and then Is_Tagged_Type (T) then
21262 if Nkind (Parent (Def)) = N_Full_Type_Declaration then
21263 Typ := Parent (Def);
21266 (Nkind (Parent (Def)) = N_Derived_Type_Definition);
21267 Typ := Parent (Parent (Def));
21270 Ctxt := Parent (Typ);
21272 if Nkind (Ctxt) = N_Package_Body
21273 and then Nkind (Parent (Ctxt)) = N_Compilation_Unit
21275 Check_SPARK_05_Restriction
21276 ("type should be defined in package specification", Typ);
21278 elsif Nkind (Ctxt) /= N_Package_Specification
21279 or else Nkind (Parent (Parent (Ctxt))) /= N_Compilation_Unit
21281 Check_SPARK_05_Restriction
21282 ("type should be defined in library unit package", Typ);
21287 Final_Storage_Only := not Is_Controlled_Active (T);
21289 -- Ada 2005: Check whether an explicit Limited is present in a derived
21290 -- type declaration.
21292 if Nkind (Parent (Def)) = N_Derived_Type_Definition
21293 and then Limited_Present (Parent (Def))
21295 Set_Is_Limited_Record (T);
21298 -- If the component list of a record type is defined by the reserved
21299 -- word null and there is no discriminant part, then the record type has
21300 -- no components and all records of the type are null records (RM 3.7)
21301 -- This procedure is also called to process the extension part of a
21302 -- record extension, in which case the current scope may have inherited
21306 or else No (Component_List (Def))
21307 or else Null_Present (Component_List (Def))
21309 if not Is_Tagged_Type (T) then
21310 Check_SPARK_05_Restriction ("untagged record cannot be null", Def);
21314 Analyze_Declarations (Component_Items (Component_List (Def)));
21316 if Present (Variant_Part (Component_List (Def))) then
21317 Check_SPARK_05_Restriction ("variant part is not allowed", Def);
21318 Analyze (Variant_Part (Component_List (Def)));
21322 -- After completing the semantic analysis of the record definition,
21323 -- record components, both new and inherited, are accessible. Set their
21324 -- kind accordingly. Exclude malformed itypes from illegal declarations,
21325 -- whose Ekind may be void.
21327 Component := First_Entity (Current_Scope);
21328 while Present (Component) loop
21329 if Ekind (Component) = E_Void
21330 and then not Is_Itype (Component)
21332 Set_Ekind (Component, E_Component);
21333 Init_Component_Location (Component);
21336 if Has_Task (Etype (Component)) then
21340 if Has_Protected (Etype (Component)) then
21341 Set_Has_Protected (T);
21344 if Ekind (Component) /= E_Component then
21347 -- Do not set Has_Controlled_Component on a class-wide equivalent
21348 -- type. See Make_CW_Equivalent_Type.
21350 elsif not Is_Class_Wide_Equivalent_Type (T)
21351 and then (Has_Controlled_Component (Etype (Component))
21352 or else (Chars (Component) /= Name_uParent
21353 and then Is_Controlled_Active
21354 (Etype (Component))))
21356 Set_Has_Controlled_Component (T, True);
21357 Final_Storage_Only :=
21359 and then Finalize_Storage_Only (Etype (Component));
21360 Ctrl_Components := True;
21363 Next_Entity (Component);
21366 -- A Type is Finalize_Storage_Only only if all its controlled components
21369 if Ctrl_Components then
21370 Set_Finalize_Storage_Only (T, Final_Storage_Only);
21373 -- Place reference to end record on the proper entity, which may
21374 -- be a partial view.
21376 if Present (Def) then
21377 Process_End_Label (Def, 'e', Prev_T);
21379 end Record_Type_Definition;
21381 ------------------------
21382 -- Replace_Components --
21383 ------------------------
21385 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
21386 function Process (N : Node_Id) return Traverse_Result;
21392 function Process (N : Node_Id) return Traverse_Result is
21396 if Nkind (N) = N_Discriminant_Specification then
21397 Comp := First_Discriminant (Typ);
21398 while Present (Comp) loop
21399 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21400 Set_Defining_Identifier (N, Comp);
21404 Next_Discriminant (Comp);
21407 elsif Nkind (N) = N_Component_Declaration then
21408 Comp := First_Component (Typ);
21409 while Present (Comp) loop
21410 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21411 Set_Defining_Identifier (N, Comp);
21415 Next_Component (Comp);
21422 procedure Replace is new Traverse_Proc (Process);
21424 -- Start of processing for Replace_Components
21428 end Replace_Components;
21430 -------------------------------
21431 -- Set_Completion_Referenced --
21432 -------------------------------
21434 procedure Set_Completion_Referenced (E : Entity_Id) is
21436 -- If in main unit, mark entity that is a completion as referenced,
21437 -- warnings go on the partial view when needed.
21439 if In_Extended_Main_Source_Unit (E) then
21440 Set_Referenced (E);
21442 end Set_Completion_Referenced;
21444 ---------------------
21445 -- Set_Default_SSO --
21446 ---------------------
21448 procedure Set_Default_SSO (T : Entity_Id) is
21450 case Opt.Default_SSO is
21454 Set_SSO_Set_Low_By_Default (T, True);
21456 Set_SSO_Set_High_By_Default (T, True);
21458 raise Program_Error;
21460 end Set_Default_SSO;
21462 ---------------------
21463 -- Set_Fixed_Range --
21464 ---------------------
21466 -- The range for fixed-point types is complicated by the fact that we
21467 -- do not know the exact end points at the time of the declaration. This
21468 -- is true for three reasons:
21470 -- A size clause may affect the fudging of the end-points.
21471 -- A small clause may affect the values of the end-points.
21472 -- We try to include the end-points if it does not affect the size.
21474 -- This means that the actual end-points must be established at the
21475 -- point when the type is frozen. Meanwhile, we first narrow the range
21476 -- as permitted (so that it will fit if necessary in a small specified
21477 -- size), and then build a range subtree with these narrowed bounds.
21478 -- Set_Fixed_Range constructs the range from real literal values, and
21479 -- sets the range as the Scalar_Range of the given fixed-point type entity.
21481 -- The parent of this range is set to point to the entity so that it is
21482 -- properly hooked into the tree (unlike normal Scalar_Range entries for
21483 -- other scalar types, which are just pointers to the range in the
21484 -- original tree, this would otherwise be an orphan).
21486 -- The tree is left unanalyzed. When the type is frozen, the processing
21487 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
21488 -- analyzed, and uses this as an indication that it should complete
21489 -- work on the range (it will know the final small and size values).
21491 procedure Set_Fixed_Range
21497 S : constant Node_Id :=
21499 Low_Bound => Make_Real_Literal (Loc, Lo),
21500 High_Bound => Make_Real_Literal (Loc, Hi));
21502 Set_Scalar_Range (E, S);
21505 -- Before the freeze point, the bounds of a fixed point are universal
21506 -- and carry the corresponding type.
21508 Set_Etype (Low_Bound (S), Universal_Real);
21509 Set_Etype (High_Bound (S), Universal_Real);
21510 end Set_Fixed_Range;
21512 ----------------------------------
21513 -- Set_Scalar_Range_For_Subtype --
21514 ----------------------------------
21516 procedure Set_Scalar_Range_For_Subtype
21517 (Def_Id : Entity_Id;
21521 Kind : constant Entity_Kind := Ekind (Def_Id);
21524 -- Defend against previous error
21526 if Nkind (R) = N_Error then
21530 Set_Scalar_Range (Def_Id, R);
21532 -- We need to link the range into the tree before resolving it so
21533 -- that types that are referenced, including importantly the subtype
21534 -- itself, are properly frozen (Freeze_Expression requires that the
21535 -- expression be properly linked into the tree). Of course if it is
21536 -- already linked in, then we do not disturb the current link.
21538 if No (Parent (R)) then
21539 Set_Parent (R, Def_Id);
21542 -- Reset the kind of the subtype during analysis of the range, to
21543 -- catch possible premature use in the bounds themselves.
21545 Set_Ekind (Def_Id, E_Void);
21546 Process_Range_Expr_In_Decl (R, Subt, Subtyp => Def_Id);
21547 Set_Ekind (Def_Id, Kind);
21548 end Set_Scalar_Range_For_Subtype;
21550 --------------------------------------------------------
21551 -- Set_Stored_Constraint_From_Discriminant_Constraint --
21552 --------------------------------------------------------
21554 procedure Set_Stored_Constraint_From_Discriminant_Constraint
21558 -- Make sure set if encountered during Expand_To_Stored_Constraint
21560 Set_Stored_Constraint (E, No_Elist);
21562 -- Give it the right value
21564 if Is_Constrained (E) and then Has_Discriminants (E) then
21565 Set_Stored_Constraint (E,
21566 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
21568 end Set_Stored_Constraint_From_Discriminant_Constraint;
21570 -------------------------------------
21571 -- Signed_Integer_Type_Declaration --
21572 -------------------------------------
21574 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
21575 Implicit_Base : Entity_Id;
21576 Base_Typ : Entity_Id;
21579 Errs : Boolean := False;
21583 function Can_Derive_From (E : Entity_Id) return Boolean;
21584 -- Determine whether given bounds allow derivation from specified type
21586 procedure Check_Bound (Expr : Node_Id);
21587 -- Check bound to make sure it is integral and static. If not, post
21588 -- appropriate error message and set Errs flag
21590 ---------------------
21591 -- Can_Derive_From --
21592 ---------------------
21594 -- Note we check both bounds against both end values, to deal with
21595 -- strange types like ones with a range of 0 .. -12341234.
21597 function Can_Derive_From (E : Entity_Id) return Boolean is
21598 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
21599 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
21601 return Lo <= Lo_Val and then Lo_Val <= Hi
21603 Lo <= Hi_Val and then Hi_Val <= Hi;
21604 end Can_Derive_From;
21610 procedure Check_Bound (Expr : Node_Id) is
21612 -- If a range constraint is used as an integer type definition, each
21613 -- bound of the range must be defined by a static expression of some
21614 -- integer type, but the two bounds need not have the same integer
21615 -- type (Negative bounds are allowed.) (RM 3.5.4)
21617 if not Is_Integer_Type (Etype (Expr)) then
21619 ("integer type definition bounds must be of integer type", Expr);
21622 elsif not Is_OK_Static_Expression (Expr) then
21623 Flag_Non_Static_Expr
21624 ("non-static expression used for integer type bound!", Expr);
21627 -- The bounds are folded into literals, and we set their type to be
21628 -- universal, to avoid typing difficulties: we cannot set the type
21629 -- of the literal to the new type, because this would be a forward
21630 -- reference for the back end, and if the original type is user-
21631 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
21634 if Is_Entity_Name (Expr) then
21635 Fold_Uint (Expr, Expr_Value (Expr), True);
21638 Set_Etype (Expr, Universal_Integer);
21642 -- Start of processing for Signed_Integer_Type_Declaration
21645 -- Create an anonymous base type
21648 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
21650 -- Analyze and check the bounds, they can be of any integer type
21652 Lo := Low_Bound (Def);
21653 Hi := High_Bound (Def);
21655 -- Arbitrarily use Integer as the type if either bound had an error
21657 if Hi = Error or else Lo = Error then
21658 Base_Typ := Any_Integer;
21659 Set_Error_Posted (T, True);
21661 -- Here both bounds are OK expressions
21664 Analyze_And_Resolve (Lo, Any_Integer);
21665 Analyze_And_Resolve (Hi, Any_Integer);
21671 Hi := Type_High_Bound (Standard_Long_Long_Integer);
21672 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
21675 -- Find type to derive from
21677 Lo_Val := Expr_Value (Lo);
21678 Hi_Val := Expr_Value (Hi);
21680 if Can_Derive_From (Standard_Short_Short_Integer) then
21681 Base_Typ := Base_Type (Standard_Short_Short_Integer);
21683 elsif Can_Derive_From (Standard_Short_Integer) then
21684 Base_Typ := Base_Type (Standard_Short_Integer);
21686 elsif Can_Derive_From (Standard_Integer) then
21687 Base_Typ := Base_Type (Standard_Integer);
21689 elsif Can_Derive_From (Standard_Long_Integer) then
21690 Base_Typ := Base_Type (Standard_Long_Integer);
21692 elsif Can_Derive_From (Standard_Long_Long_Integer) then
21693 Check_Restriction (No_Long_Long_Integers, Def);
21694 Base_Typ := Base_Type (Standard_Long_Long_Integer);
21697 Base_Typ := Base_Type (Standard_Long_Long_Integer);
21698 Error_Msg_N ("integer type definition bounds out of range", Def);
21699 Hi := Type_High_Bound (Standard_Long_Long_Integer);
21700 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
21704 -- Complete both implicit base and declared first subtype entities. The
21705 -- inheritance of the rep item chain ensures that SPARK-related pragmas
21706 -- are not clobbered when the signed integer type acts as a full view of
21709 Set_Etype (Implicit_Base, Base_Typ);
21710 Set_Size_Info (Implicit_Base, Base_Typ);
21711 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
21712 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
21713 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
21715 Set_Ekind (T, E_Signed_Integer_Subtype);
21716 Set_Etype (T, Implicit_Base);
21717 Set_Size_Info (T, Implicit_Base);
21718 Inherit_Rep_Item_Chain (T, Implicit_Base);
21719 Set_Scalar_Range (T, Def);
21720 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
21721 Set_Is_Constrained (T);
21722 end Signed_Integer_Type_Declaration;