1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2010, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree; use Atree;
27 with Checks; use Checks;
28 with Debug; use Debug;
29 with Elists; use Elists;
30 with Einfo; use Einfo;
31 with Errout; use Errout;
32 with Eval_Fat; use Eval_Fat;
33 with Exp_Ch3; use Exp_Ch3;
34 with Exp_Ch9; use Exp_Ch9;
35 with Exp_Disp; use Exp_Disp;
36 with Exp_Dist; use Exp_Dist;
37 with Exp_Tss; use Exp_Tss;
38 with Exp_Util; use Exp_Util;
39 with Fname; use Fname;
40 with Freeze; use Freeze;
41 with Itypes; use Itypes;
42 with Layout; use Layout;
44 with Lib.Xref; use Lib.Xref;
45 with Namet; use Namet;
46 with Nmake; use Nmake;
48 with Restrict; use Restrict;
49 with Rident; use Rident;
50 with Rtsfind; use Rtsfind;
52 with Sem_Aux; use Sem_Aux;
53 with Sem_Case; use Sem_Case;
54 with Sem_Cat; use Sem_Cat;
55 with Sem_Ch6; use Sem_Ch6;
56 with Sem_Ch7; use Sem_Ch7;
57 with Sem_Ch8; use Sem_Ch8;
58 with Sem_Ch13; use Sem_Ch13;
59 with Sem_Disp; use Sem_Disp;
60 with Sem_Dist; use Sem_Dist;
61 with Sem_Elim; use Sem_Elim;
62 with Sem_Eval; use Sem_Eval;
63 with Sem_Mech; use Sem_Mech;
64 with Sem_Res; use Sem_Res;
65 with Sem_Smem; use Sem_Smem;
66 with Sem_Type; use Sem_Type;
67 with Sem_Util; use Sem_Util;
68 with Sem_Warn; use Sem_Warn;
69 with Stand; use Stand;
70 with Sinfo; use Sinfo;
71 with Snames; use Snames;
72 with Targparm; use Targparm;
73 with Tbuild; use Tbuild;
74 with Ttypes; use Ttypes;
75 with Uintp; use Uintp;
76 with Urealp; use Urealp;
78 package body Sem_Ch3 is
80 -----------------------
81 -- Local Subprograms --
82 -----------------------
84 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id);
85 -- Ada 2005 (AI-251): Add the tag components corresponding to all the
86 -- abstract interface types implemented by a record type or a derived
89 procedure Build_Derived_Type
91 Parent_Type : Entity_Id;
92 Derived_Type : Entity_Id;
93 Is_Completion : Boolean;
94 Derive_Subps : Boolean := True);
95 -- Create and decorate a Derived_Type given the Parent_Type entity. N is
96 -- the N_Full_Type_Declaration node containing the derived type definition.
97 -- Parent_Type is the entity for the parent type in the derived type
98 -- definition and Derived_Type the actual derived type. Is_Completion must
99 -- be set to False if Derived_Type is the N_Defining_Identifier node in N
100 -- (i.e. Derived_Type = Defining_Identifier (N)). In this case N is not the
101 -- completion of a private type declaration. If Is_Completion is set to
102 -- True, N is the completion of a private type declaration and Derived_Type
103 -- is different from the defining identifier inside N (i.e. Derived_Type /=
104 -- Defining_Identifier (N)). Derive_Subps indicates whether the parent
105 -- subprograms should be derived. The only case where this parameter is
106 -- False is when Build_Derived_Type is recursively called to process an
107 -- implicit derived full type for a type derived from a private type (in
108 -- that case the subprograms must only be derived for the private view of
111 -- ??? These flags need a bit of re-examination and re-documentation:
112 -- ??? are they both necessary (both seem related to the recursion)?
114 procedure Build_Derived_Access_Type
116 Parent_Type : Entity_Id;
117 Derived_Type : Entity_Id);
118 -- Subsidiary procedure to Build_Derived_Type. For a derived access type,
119 -- create an implicit base if the parent type is constrained or if the
120 -- subtype indication has a constraint.
122 procedure Build_Derived_Array_Type
124 Parent_Type : Entity_Id;
125 Derived_Type : Entity_Id);
126 -- Subsidiary procedure to Build_Derived_Type. For a derived array type,
127 -- create an implicit base if the parent type is constrained or if the
128 -- subtype indication has a constraint.
130 procedure Build_Derived_Concurrent_Type
132 Parent_Type : Entity_Id;
133 Derived_Type : Entity_Id);
134 -- Subsidiary procedure to Build_Derived_Type. For a derived task or
135 -- protected type, inherit entries and protected subprograms, check
136 -- legality of discriminant constraints if any.
138 procedure Build_Derived_Enumeration_Type
140 Parent_Type : Entity_Id;
141 Derived_Type : Entity_Id);
142 -- Subsidiary procedure to Build_Derived_Type. For a derived enumeration
143 -- type, we must create a new list of literals. Types derived from
144 -- Character and [Wide_]Wide_Character are special-cased.
146 procedure Build_Derived_Numeric_Type
148 Parent_Type : Entity_Id;
149 Derived_Type : Entity_Id);
150 -- Subsidiary procedure to Build_Derived_Type. For numeric types, create
151 -- an anonymous base type, and propagate constraint to subtype if needed.
153 procedure Build_Derived_Private_Type
155 Parent_Type : Entity_Id;
156 Derived_Type : Entity_Id;
157 Is_Completion : Boolean;
158 Derive_Subps : Boolean := True);
159 -- Subsidiary procedure to Build_Derived_Type. This procedure is complex
160 -- because the parent may or may not have a completion, and the derivation
161 -- may itself be a completion.
163 procedure Build_Derived_Record_Type
165 Parent_Type : Entity_Id;
166 Derived_Type : Entity_Id;
167 Derive_Subps : Boolean := True);
168 -- Subsidiary procedure for Build_Derived_Type and
169 -- Analyze_Private_Extension_Declaration used for tagged and untagged
170 -- record types. All parameters are as in Build_Derived_Type except that
171 -- N, in addition to being an N_Full_Type_Declaration node, can also be an
172 -- N_Private_Extension_Declaration node. See the definition of this routine
173 -- for much more info. Derive_Subps indicates whether subprograms should
174 -- be derived from the parent type. The only case where Derive_Subps is
175 -- False is for an implicit derived full type for a type derived from a
176 -- private type (see Build_Derived_Type).
178 procedure Build_Discriminal (Discrim : Entity_Id);
179 -- Create the discriminal corresponding to discriminant Discrim, that is
180 -- the parameter corresponding to Discrim to be used in initialization
181 -- procedures for the type where Discrim is a discriminant. Discriminals
182 -- are not used during semantic analysis, and are not fully defined
183 -- entities until expansion. Thus they are not given a scope until
184 -- initialization procedures are built.
186 function Build_Discriminant_Constraints
189 Derived_Def : Boolean := False) return Elist_Id;
190 -- Validate discriminant constraints and return the list of the constraints
191 -- in order of discriminant declarations, where T is the discriminated
192 -- unconstrained type. Def is the N_Subtype_Indication node where the
193 -- discriminants constraints for T are specified. Derived_Def is True
194 -- when building the discriminant constraints in a derived type definition
195 -- of the form "type D (...) is new T (xxx)". In this case T is the parent
196 -- type and Def is the constraint "(xxx)" on T and this routine sets the
197 -- Corresponding_Discriminant field of the discriminants in the derived
198 -- type D to point to the corresponding discriminants in the parent type T.
200 procedure Build_Discriminated_Subtype
204 Related_Nod : Node_Id;
205 For_Access : Boolean := False);
206 -- Subsidiary procedure to Constrain_Discriminated_Type and to
207 -- Process_Incomplete_Dependents. Given
209 -- T (a possibly discriminated base type)
210 -- Def_Id (a very partially built subtype for T),
212 -- the call completes Def_Id to be the appropriate E_*_Subtype.
214 -- The Elist is the list of discriminant constraints if any (it is set
215 -- to No_Elist if T is not a discriminated type, and to an empty list if
216 -- T has discriminants but there are no discriminant constraints). The
217 -- Related_Nod is the same as Decl_Node in Create_Constrained_Components.
218 -- The For_Access says whether or not this subtype is really constraining
219 -- an access type. That is its sole purpose is the designated type of an
220 -- access type -- in which case a Private_Subtype Is_For_Access_Subtype
221 -- is built to avoid freezing T when the access subtype is frozen.
223 function Build_Scalar_Bound
226 Der_T : Entity_Id) return Node_Id;
227 -- The bounds of a derived scalar type are conversions of the bounds of
228 -- the parent type. Optimize the representation if the bounds are literals.
229 -- Needs a more complete spec--what are the parameters exactly, and what
230 -- exactly is the returned value, and how is Bound affected???
232 procedure Build_Underlying_Full_View
236 -- If the completion of a private type is itself derived from a private
237 -- type, or if the full view of a private subtype is itself private, the
238 -- back-end has no way to compute the actual size of this type. We build
239 -- an internal subtype declaration of the proper parent type to convey
240 -- this information. This extra mechanism is needed because a full
241 -- view cannot itself have a full view (it would get clobbered during
244 procedure Check_Access_Discriminant_Requires_Limited
247 -- Check the restriction that the type to which an access discriminant
248 -- belongs must be a concurrent type or a descendant of a type with
249 -- the reserved word 'limited' in its declaration.
251 procedure Check_Anonymous_Access_Components
255 Comp_List : Node_Id);
256 -- Ada 2005 AI-382: an access component in a record definition can refer to
257 -- the enclosing record, in which case it denotes the type itself, and not
258 -- the current instance of the type. We create an anonymous access type for
259 -- the component, and flag it as an access to a component, so accessibility
260 -- checks are properly performed on it. The declaration of the access type
261 -- is placed ahead of that of the record to prevent order-of-elaboration
262 -- circularity issues in Gigi. We create an incomplete type for the record
263 -- declaration, which is the designated type of the anonymous access.
265 procedure Check_Delta_Expression (E : Node_Id);
266 -- Check that the expression represented by E is suitable for use as a
267 -- delta expression, i.e. it is of real type and is static.
269 procedure Check_Digits_Expression (E : Node_Id);
270 -- Check that the expression represented by E is suitable for use as a
271 -- digits expression, i.e. it is of integer type, positive and static.
273 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id);
274 -- Validate the initialization of an object declaration. T is the required
275 -- type, and Exp is the initialization expression.
277 procedure Check_Interfaces (N : Node_Id; Def : Node_Id);
278 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
280 procedure Check_Or_Process_Discriminants
283 Prev : Entity_Id := Empty);
284 -- If T is the full declaration of an incomplete or private type, check the
285 -- conformance of the discriminants, otherwise process them. Prev is the
286 -- entity of the partial declaration, if any.
288 procedure Check_Real_Bound (Bound : Node_Id);
289 -- Check given bound for being of real type and static. If not, post an
290 -- appropriate message, and rewrite the bound with the real literal zero.
292 procedure Constant_Redeclaration
296 -- Various checks on legality of full declaration of deferred constant.
297 -- Id is the entity for the redeclaration, N is the N_Object_Declaration,
298 -- node. The caller has not yet set any attributes of this entity.
300 function Contain_Interface
302 Ifaces : Elist_Id) return Boolean;
303 -- Ada 2005: Determine whether Iface is present in the list Ifaces
305 procedure Convert_Scalar_Bounds
307 Parent_Type : Entity_Id;
308 Derived_Type : Entity_Id;
310 -- For derived scalar types, convert the bounds in the type definition to
311 -- the derived type, and complete their analysis. Given a constraint of the
312 -- form ".. new T range Lo .. Hi", Lo and Hi are analyzed and resolved with
313 -- T'Base, the parent_type. The bounds of the derived type (the anonymous
314 -- base) are copies of Lo and Hi. Finally, the bounds of the derived
315 -- subtype are conversions of those bounds to the derived_type, so that
316 -- their typing is consistent.
318 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id);
319 -- Copies attributes from array base type T2 to array base type T1. Copies
320 -- only attributes that apply to base types, but not subtypes.
322 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id);
323 -- Copies attributes from array subtype T2 to array subtype T1. Copies
324 -- attributes that apply to both subtypes and base types.
326 procedure Create_Constrained_Components
330 Constraints : Elist_Id);
331 -- Build the list of entities for a constrained discriminated record
332 -- subtype. If a component depends on a discriminant, replace its subtype
333 -- using the discriminant values in the discriminant constraint. Subt
334 -- is the defining identifier for the subtype whose list of constrained
335 -- entities we will create. Decl_Node is the type declaration node where
336 -- we will attach all the itypes created. Typ is the base discriminated
337 -- type for the subtype Subt. Constraints is the list of discriminant
338 -- constraints for Typ.
340 function Constrain_Component_Type
342 Constrained_Typ : Entity_Id;
343 Related_Node : Node_Id;
345 Constraints : Elist_Id) return Entity_Id;
346 -- Given a discriminated base type Typ, a list of discriminant constraint
347 -- Constraints for Typ and a component of Typ, with type Compon_Type,
348 -- create and return the type corresponding to Compon_type where all
349 -- discriminant references are replaced with the corresponding constraint.
350 -- If no discriminant references occur in Compon_Typ then return it as is.
351 -- Constrained_Typ is the final constrained subtype to which the
352 -- constrained Compon_Type belongs. Related_Node is the node where we will
353 -- attach all the itypes created.
355 -- Above description is confused, what is Compon_Type???
357 procedure Constrain_Access
358 (Def_Id : in out Entity_Id;
360 Related_Nod : Node_Id);
361 -- Apply a list of constraints to an access type. If Def_Id is empty, it is
362 -- an anonymous type created for a subtype indication. In that case it is
363 -- created in the procedure and attached to Related_Nod.
365 procedure Constrain_Array
366 (Def_Id : in out Entity_Id;
368 Related_Nod : Node_Id;
369 Related_Id : Entity_Id;
371 -- Apply a list of index constraints to an unconstrained array type. The
372 -- first parameter is the entity for the resulting subtype. A value of
373 -- Empty for Def_Id indicates that an implicit type must be created, but
374 -- creation is delayed (and must be done by this procedure) because other
375 -- subsidiary implicit types must be created first (which is why Def_Id
376 -- is an in/out parameter). The second parameter is a subtype indication
377 -- node for the constrained array to be created (e.g. something of the
378 -- form string (1 .. 10)). Related_Nod gives the place where this type
379 -- has to be inserted in the tree. The Related_Id and Suffix parameters
380 -- are used to build the associated Implicit type name.
382 procedure Constrain_Concurrent
383 (Def_Id : in out Entity_Id;
385 Related_Nod : Node_Id;
386 Related_Id : Entity_Id;
388 -- Apply list of discriminant constraints to an unconstrained concurrent
391 -- SI is the N_Subtype_Indication node containing the constraint and
392 -- the unconstrained type to constrain.
394 -- Def_Id is the entity for the resulting constrained subtype. A value
395 -- of Empty for Def_Id indicates that an implicit type must be created,
396 -- but creation is delayed (and must be done by this procedure) because
397 -- other subsidiary implicit types must be created first (which is why
398 -- Def_Id is an in/out parameter).
400 -- Related_Nod gives the place where this type has to be inserted
403 -- The last two arguments are used to create its external name if needed.
405 function Constrain_Corresponding_Record
406 (Prot_Subt : Entity_Id;
407 Corr_Rec : Entity_Id;
408 Related_Nod : Node_Id;
409 Related_Id : Entity_Id) return Entity_Id;
410 -- When constraining a protected type or task type with discriminants,
411 -- constrain the corresponding record with the same discriminant values.
413 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id);
414 -- Constrain a decimal fixed point type with a digits constraint and/or a
415 -- range constraint, and build E_Decimal_Fixed_Point_Subtype entity.
417 procedure Constrain_Discriminated_Type
420 Related_Nod : Node_Id;
421 For_Access : Boolean := False);
422 -- Process discriminant constraints of composite type. Verify that values
423 -- have been provided for all discriminants, that the original type is
424 -- unconstrained, and that the types of the supplied expressions match
425 -- the discriminant types. The first three parameters are like in routine
426 -- Constrain_Concurrent. See Build_Discriminated_Subtype for an explanation
429 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id);
430 -- Constrain an enumeration type with a range constraint. This is identical
431 -- to Constrain_Integer, but for the Ekind of the resulting subtype.
433 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id);
434 -- Constrain a floating point type with either a digits constraint
435 -- and/or a range constraint, building a E_Floating_Point_Subtype.
437 procedure Constrain_Index
440 Related_Nod : Node_Id;
441 Related_Id : Entity_Id;
444 -- Process an index constraint in a constrained array declaration. The
445 -- constraint can be a subtype name, or a range with or without an explicit
446 -- subtype mark. The index is the corresponding index of the unconstrained
447 -- array. The Related_Id and Suffix parameters are used to build the
448 -- associated Implicit type name.
450 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id);
451 -- Build subtype of a signed or modular integer type
453 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id);
454 -- Constrain an ordinary fixed point type with a range constraint, and
455 -- build an E_Ordinary_Fixed_Point_Subtype entity.
457 procedure Copy_And_Swap (Priv, Full : Entity_Id);
458 -- Copy the Priv entity into the entity of its full declaration then swap
459 -- the two entities in such a manner that the former private type is now
460 -- seen as a full type.
462 procedure Decimal_Fixed_Point_Type_Declaration
465 -- Create a new decimal fixed point type, and apply the constraint to
466 -- obtain a subtype of this new type.
468 procedure Complete_Private_Subtype
471 Full_Base : Entity_Id;
472 Related_Nod : Node_Id);
473 -- Complete the implicit full view of a private subtype by setting the
474 -- appropriate semantic fields. If the full view of the parent is a record
475 -- type, build constrained components of subtype.
477 procedure Derive_Progenitor_Subprograms
478 (Parent_Type : Entity_Id;
479 Tagged_Type : Entity_Id);
480 -- Ada 2005 (AI-251): To complete type derivation, collect the primitive
481 -- operations of progenitors of Tagged_Type, and replace the subsidiary
482 -- subtypes with Tagged_Type, to build the specs of the inherited interface
483 -- primitives. The derived primitives are aliased to those of the
484 -- interface. This routine takes care also of transferring to the full-view
485 -- subprograms associated with the partial-view of Tagged_Type that cover
486 -- interface primitives.
488 procedure Derived_Standard_Character
490 Parent_Type : Entity_Id;
491 Derived_Type : Entity_Id);
492 -- Subsidiary procedure to Build_Derived_Enumeration_Type which handles
493 -- derivations from types Standard.Character and Standard.Wide_Character.
495 procedure Derived_Type_Declaration
498 Is_Completion : Boolean);
499 -- Process a derived type declaration. Build_Derived_Type is invoked
500 -- to process the actual derived type definition. Parameters N and
501 -- Is_Completion have the same meaning as in Build_Derived_Type.
502 -- T is the N_Defining_Identifier for the entity defined in the
503 -- N_Full_Type_Declaration node N, that is T is the derived type.
505 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id);
506 -- Insert each literal in symbol table, as an overloadable identifier. Each
507 -- enumeration type is mapped into a sequence of integers, and each literal
508 -- is defined as a constant with integer value. If any of the literals are
509 -- character literals, the type is a character type, which means that
510 -- strings are legal aggregates for arrays of components of the type.
512 function Expand_To_Stored_Constraint
514 Constraint : Elist_Id) return Elist_Id;
515 -- Given a constraint (i.e. a list of expressions) on the discriminants of
516 -- Typ, expand it into a constraint on the stored discriminants and return
517 -- the new list of expressions constraining the stored discriminants.
519 function Find_Type_Of_Object
521 Related_Nod : Node_Id) return Entity_Id;
522 -- Get type entity for object referenced by Obj_Def, attaching the
523 -- implicit types generated to Related_Nod
525 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id);
526 -- Create a new float and apply the constraint to obtain subtype of it
528 function Has_Range_Constraint (N : Node_Id) return Boolean;
529 -- Given an N_Subtype_Indication node N, return True if a range constraint
530 -- is present, either directly, or as part of a digits or delta constraint.
531 -- In addition, a digits constraint in the decimal case returns True, since
532 -- it establishes a default range if no explicit range is present.
534 function Inherit_Components
536 Parent_Base : Entity_Id;
537 Derived_Base : Entity_Id;
539 Inherit_Discr : Boolean;
540 Discs : Elist_Id) return Elist_Id;
541 -- Called from Build_Derived_Record_Type to inherit the components of
542 -- Parent_Base (a base type) into the Derived_Base (the derived base type).
543 -- For more information on derived types and component inheritance please
544 -- consult the comment above the body of Build_Derived_Record_Type.
546 -- N is the original derived type declaration
548 -- Is_Tagged is set if we are dealing with tagged types
550 -- If Inherit_Discr is set, Derived_Base inherits its discriminants from
551 -- Parent_Base, otherwise no discriminants are inherited.
553 -- Discs gives the list of constraints that apply to Parent_Base in the
554 -- derived type declaration. If Discs is set to No_Elist, then we have
555 -- the following situation:
557 -- type Parent (D1..Dn : ..) is [tagged] record ...;
558 -- type Derived is new Parent [with ...];
560 -- which gets treated as
562 -- type Derived (D1..Dn : ..) is new Parent (D1,..,Dn) [with ...];
564 -- For untagged types the returned value is an association list. The list
565 -- starts from the association (Parent_Base => Derived_Base), and then it
566 -- contains a sequence of the associations of the form
568 -- (Old_Component => New_Component),
570 -- where Old_Component is the Entity_Id of a component in Parent_Base and
571 -- New_Component is the Entity_Id of the corresponding component in
572 -- Derived_Base. For untagged records, this association list is needed when
573 -- copying the record declaration for the derived base. In the tagged case
574 -- the value returned is irrelevant.
576 function Is_Progenitor
578 Typ : Entity_Id) return Boolean;
579 -- Determine whether the interface Iface is implemented by Typ. It requires
580 -- traversing the list of abstract interfaces of the type, as well as that
581 -- of the ancestor types. The predicate is used to determine when a formal
582 -- in the signature of an inherited operation must carry the derived type.
584 function Is_Valid_Constraint_Kind
586 Constraint_Kind : Node_Kind) return Boolean;
587 -- Returns True if it is legal to apply the given kind of constraint to the
588 -- given kind of type (index constraint to an array type, for example).
590 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id);
591 -- Create new modular type. Verify that modulus is in bounds and is
592 -- a power of two (implementation restriction).
594 procedure New_Concatenation_Op (Typ : Entity_Id);
595 -- Create an abbreviated declaration for an operator in order to
596 -- materialize concatenation on array types.
598 procedure Ordinary_Fixed_Point_Type_Declaration
601 -- Create a new ordinary fixed point type, and apply the constraint to
602 -- obtain subtype of it.
604 procedure Prepare_Private_Subtype_Completion
606 Related_Nod : Node_Id);
607 -- Id is a subtype of some private type. Creates the full declaration
608 -- associated with Id whenever possible, i.e. when the full declaration
609 -- of the base type is already known. Records each subtype into
610 -- Private_Dependents of the base type.
612 procedure Process_Incomplete_Dependents
616 -- Process all entities that depend on an incomplete type. There include
617 -- subtypes, subprogram types that mention the incomplete type in their
618 -- profiles, and subprogram with access parameters that designate the
621 -- Inc_T is the defining identifier of an incomplete type declaration, its
622 -- Ekind is E_Incomplete_Type.
624 -- N is the corresponding N_Full_Type_Declaration for Inc_T.
626 -- Full_T is N's defining identifier.
628 -- Subtypes of incomplete types with discriminants are completed when the
629 -- parent type is. This is simpler than private subtypes, because they can
630 -- only appear in the same scope, and there is no need to exchange views.
631 -- Similarly, access_to_subprogram types may have a parameter or a return
632 -- type that is an incomplete type, and that must be replaced with the
635 -- If the full type is tagged, subprogram with access parameters that
636 -- designated the incomplete may be primitive operations of the full type,
637 -- and have to be processed accordingly.
639 procedure Process_Real_Range_Specification (Def : Node_Id);
640 -- Given the type definition for a real type, this procedure processes and
641 -- checks the real range specification of this type definition if one is
642 -- present. If errors are found, error messages are posted, and the
643 -- Real_Range_Specification of Def is reset to Empty.
645 procedure Record_Type_Declaration
649 -- Process a record type declaration (for both untagged and tagged
650 -- records). Parameters T and N are exactly like in procedure
651 -- Derived_Type_Declaration, except that no flag Is_Completion is needed
652 -- for this routine. If this is the completion of an incomplete type
653 -- declaration, Prev is the entity of the incomplete declaration, used for
654 -- cross-referencing. Otherwise Prev = T.
656 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id);
657 -- This routine is used to process the actual record type definition (both
658 -- for untagged and tagged records). Def is a record type definition node.
659 -- This procedure analyzes the components in this record type definition.
660 -- Prev_T is the entity for the enclosing record type. It is provided so
661 -- that its Has_Task flag can be set if any of the component have Has_Task
662 -- set. If the declaration is the completion of an incomplete type
663 -- declaration, Prev_T is the original incomplete type, whose full view is
666 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id);
667 -- Subsidiary to Build_Derived_Record_Type. For untagged records, we
668 -- build a copy of the declaration tree of the parent, and we create
669 -- independently the list of components for the derived type. Semantic
670 -- information uses the component entities, but record representation
671 -- clauses are validated on the declaration tree. This procedure replaces
672 -- discriminants and components in the declaration with those that have
673 -- been created by Inherit_Components.
675 procedure Set_Fixed_Range
680 -- Build a range node with the given bounds and set it as the Scalar_Range
681 -- of the given fixed-point type entity. Loc is the source location used
682 -- for the constructed range. See body for further details.
684 procedure Set_Scalar_Range_For_Subtype
688 -- This routine is used to set the scalar range field for a subtype given
689 -- Def_Id, the entity for the subtype, and R, the range expression for the
690 -- scalar range. Subt provides the parent subtype to be used to analyze,
691 -- resolve, and check the given range.
693 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id);
694 -- Create a new signed integer entity, and apply the constraint to obtain
695 -- the required first named subtype of this type.
697 procedure Set_Stored_Constraint_From_Discriminant_Constraint
699 -- E is some record type. This routine computes E's Stored_Constraint
700 -- from its Discriminant_Constraint.
702 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id);
703 -- Check that an entity in a list of progenitors is an interface,
704 -- emit error otherwise.
706 -----------------------
707 -- Access_Definition --
708 -----------------------
710 function Access_Definition
711 (Related_Nod : Node_Id;
712 N : Node_Id) return Entity_Id
714 Loc : constant Source_Ptr := Sloc (Related_Nod);
715 Anon_Type : Entity_Id;
716 Anon_Scope : Entity_Id;
717 Desig_Type : Entity_Id;
719 Enclosing_Prot_Type : Entity_Id := Empty;
722 if Is_Entry (Current_Scope)
723 and then Is_Task_Type (Etype (Scope (Current_Scope)))
725 Error_Msg_N ("task entries cannot have access parameters", N);
729 -- Ada 2005: for an object declaration the corresponding anonymous
730 -- type is declared in the current scope.
732 -- If the access definition is the return type of another access to
733 -- function, scope is the current one, because it is the one of the
734 -- current type declaration.
736 if Nkind_In (Related_Nod, N_Object_Declaration,
737 N_Access_Function_Definition)
739 Anon_Scope := Current_Scope;
741 -- For the anonymous function result case, retrieve the scope of the
742 -- function specification's associated entity rather than using the
743 -- current scope. The current scope will be the function itself if the
744 -- formal part is currently being analyzed, but will be the parent scope
745 -- in the case of a parameterless function, and we always want to use
746 -- the function's parent scope. Finally, if the function is a child
747 -- unit, we must traverse the tree to retrieve the proper entity.
749 elsif Nkind (Related_Nod) = N_Function_Specification
750 and then Nkind (Parent (N)) /= N_Parameter_Specification
752 -- If the current scope is a protected type, the anonymous access
753 -- is associated with one of the protected operations, and must
754 -- be available in the scope that encloses the protected declaration.
755 -- Otherwise the type is in the scope enclosing the subprogram.
757 -- If the function has formals, The return type of a subprogram
758 -- declaration is analyzed in the scope of the subprogram (see
759 -- Process_Formals) and thus the protected type, if present, is
760 -- the scope of the current function scope.
762 if Ekind (Current_Scope) = E_Protected_Type then
763 Enclosing_Prot_Type := Current_Scope;
765 elsif Ekind (Current_Scope) = E_Function
766 and then Ekind (Scope (Current_Scope)) = E_Protected_Type
768 Enclosing_Prot_Type := Scope (Current_Scope);
771 if Present (Enclosing_Prot_Type) then
772 Anon_Scope := Scope (Enclosing_Prot_Type);
775 Anon_Scope := Scope (Defining_Entity (Related_Nod));
779 -- For access formals, access components, and access discriminants,
780 -- the scope is that of the enclosing declaration,
782 Anon_Scope := Scope (Current_Scope);
787 (E_Anonymous_Access_Type, Related_Nod, Scope_Id => Anon_Scope);
790 and then Ada_Version >= Ada_05
792 Error_Msg_N ("ALL is not permitted for anonymous access types", N);
795 -- Ada 2005 (AI-254): In case of anonymous access to subprograms call
796 -- the corresponding semantic routine
798 if Present (Access_To_Subprogram_Definition (N)) then
799 Access_Subprogram_Declaration
800 (T_Name => Anon_Type,
801 T_Def => Access_To_Subprogram_Definition (N));
803 if Ekind (Anon_Type) = E_Access_Protected_Subprogram_Type then
805 (Anon_Type, E_Anonymous_Access_Protected_Subprogram_Type);
808 (Anon_Type, E_Anonymous_Access_Subprogram_Type);
811 Set_Can_Use_Internal_Rep
812 (Anon_Type, not Always_Compatible_Rep_On_Target);
814 -- If the anonymous access is associated with a protected operation
815 -- create a reference to it after the enclosing protected definition
816 -- because the itype will be used in the subsequent bodies.
818 if Ekind (Current_Scope) = E_Protected_Type then
819 Build_Itype_Reference (Anon_Type, Parent (Current_Scope));
825 Find_Type (Subtype_Mark (N));
826 Desig_Type := Entity (Subtype_Mark (N));
828 Set_Directly_Designated_Type (Anon_Type, Desig_Type);
829 Set_Etype (Anon_Type, Anon_Type);
831 -- Make sure the anonymous access type has size and alignment fields
832 -- set, as required by gigi. This is necessary in the case of the
833 -- Task_Body_Procedure.
835 if not Has_Private_Component (Desig_Type) then
836 Layout_Type (Anon_Type);
839 -- ???The following makes no sense, because Anon_Type is an access type
840 -- and therefore cannot have components, private or otherwise. Hence
841 -- the assertion. Not sure what was meant, here.
842 Set_Depends_On_Private (Anon_Type, Has_Private_Component (Anon_Type));
843 pragma Assert (not Depends_On_Private (Anon_Type));
845 -- Ada 2005 (AI-231): Ada 2005 semantics for anonymous access differs
846 -- from Ada 95 semantics. In Ada 2005, anonymous access must specify if
847 -- the null value is allowed. In Ada 95 the null value is never allowed.
849 if Ada_Version >= Ada_05 then
850 Set_Can_Never_Be_Null (Anon_Type, Null_Exclusion_Present (N));
852 Set_Can_Never_Be_Null (Anon_Type, True);
855 -- The anonymous access type is as public as the discriminated type or
856 -- subprogram that defines it. It is imported (for back-end purposes)
857 -- if the designated type is.
859 Set_Is_Public (Anon_Type, Is_Public (Scope (Anon_Type)));
861 -- Ada 2005 (AI-231): Propagate the access-constant attribute
863 Set_Is_Access_Constant (Anon_Type, Constant_Present (N));
865 -- The context is either a subprogram declaration, object declaration,
866 -- or an access discriminant, in a private or a full type declaration.
867 -- In the case of a subprogram, if the designated type is incomplete,
868 -- the operation will be a primitive operation of the full type, to be
869 -- updated subsequently. If the type is imported through a limited_with
870 -- clause, the subprogram is not a primitive operation of the type
871 -- (which is declared elsewhere in some other scope).
873 if Ekind (Desig_Type) = E_Incomplete_Type
874 and then not From_With_Type (Desig_Type)
875 and then Is_Overloadable (Current_Scope)
877 Append_Elmt (Current_Scope, Private_Dependents (Desig_Type));
878 Set_Has_Delayed_Freeze (Current_Scope);
881 -- Ada 2005: if the designated type is an interface that may contain
882 -- tasks, create a Master entity for the declaration. This must be done
883 -- before expansion of the full declaration, because the declaration may
884 -- include an expression that is an allocator, whose expansion needs the
885 -- proper Master for the created tasks.
887 if Nkind (Related_Nod) = N_Object_Declaration
888 and then Expander_Active
890 if Is_Interface (Desig_Type)
891 and then Is_Limited_Record (Desig_Type)
893 Build_Class_Wide_Master (Anon_Type);
895 -- Similarly, if the type is an anonymous access that designates
896 -- tasks, create a master entity for it in the current context.
898 elsif Has_Task (Desig_Type)
899 and then Comes_From_Source (Related_Nod)
901 if not Has_Master_Entity (Current_Scope) then
903 Make_Object_Declaration (Loc,
904 Defining_Identifier =>
905 Make_Defining_Identifier (Loc, Name_uMaster),
906 Constant_Present => True,
908 New_Reference_To (RTE (RE_Master_Id), Loc),
910 Make_Explicit_Dereference (Loc,
911 New_Reference_To (RTE (RE_Current_Master), Loc)));
913 Insert_Before (Related_Nod, Decl);
916 Set_Master_Id (Anon_Type, Defining_Identifier (Decl));
917 Set_Has_Master_Entity (Current_Scope);
919 Build_Master_Renaming (Related_Nod, Anon_Type);
924 -- For a private component of a protected type, it is imperative that
925 -- the back-end elaborate the type immediately after the protected
926 -- declaration, because this type will be used in the declarations
927 -- created for the component within each protected body, so we must
928 -- create an itype reference for it now.
930 if Nkind (Parent (Related_Nod)) = N_Protected_Definition then
931 Build_Itype_Reference (Anon_Type, Parent (Parent (Related_Nod)));
933 -- Similarly, if the access definition is the return result of a
934 -- function, create an itype reference for it because it will be used
935 -- within the function body. For a regular function that is not a
936 -- compilation unit, insert reference after the declaration. For a
937 -- protected operation, insert it after the enclosing protected type
938 -- declaration. In either case, do not create a reference for a type
939 -- obtained through a limited_with clause, because this would introduce
940 -- semantic dependencies.
942 -- Similarly, do not create a reference if the designated type is a
943 -- generic formal, because no use of it will reach the backend.
945 elsif Nkind (Related_Nod) = N_Function_Specification
946 and then not From_With_Type (Desig_Type)
947 and then not Is_Generic_Type (Desig_Type)
949 if Present (Enclosing_Prot_Type) then
950 Build_Itype_Reference (Anon_Type, Parent (Enclosing_Prot_Type));
952 elsif Is_List_Member (Parent (Related_Nod))
953 and then Nkind (Parent (N)) /= N_Parameter_Specification
955 Build_Itype_Reference (Anon_Type, Parent (Related_Nod));
958 -- Finally, create an itype reference for an object declaration of an
959 -- anonymous access type. This is strictly necessary only for deferred
960 -- constants, but in any case will avoid out-of-scope problems in the
963 elsif Nkind (Related_Nod) = N_Object_Declaration then
964 Build_Itype_Reference (Anon_Type, Related_Nod);
968 end Access_Definition;
970 -----------------------------------
971 -- Access_Subprogram_Declaration --
972 -----------------------------------
974 procedure Access_Subprogram_Declaration
979 procedure Check_For_Premature_Usage (Def : Node_Id);
980 -- Check that type T_Name is not used, directly or recursively, as a
981 -- parameter or a return type in Def. Def is either a subtype, an
982 -- access_definition, or an access_to_subprogram_definition.
984 -------------------------------
985 -- Check_For_Premature_Usage --
986 -------------------------------
988 procedure Check_For_Premature_Usage (Def : Node_Id) is
992 -- Check for a subtype mark
994 if Nkind (Def) in N_Has_Etype then
995 if Etype (Def) = T_Name then
997 ("type& cannot be used before end of its declaration", Def);
1000 -- If this is not a subtype, then this is an access_definition
1002 elsif Nkind (Def) = N_Access_Definition then
1003 if Present (Access_To_Subprogram_Definition (Def)) then
1004 Check_For_Premature_Usage
1005 (Access_To_Subprogram_Definition (Def));
1007 Check_For_Premature_Usage (Subtype_Mark (Def));
1010 -- The only cases left are N_Access_Function_Definition and
1011 -- N_Access_Procedure_Definition.
1014 if Present (Parameter_Specifications (Def)) then
1015 Param := First (Parameter_Specifications (Def));
1016 while Present (Param) loop
1017 Check_For_Premature_Usage (Parameter_Type (Param));
1018 Param := Next (Param);
1022 if Nkind (Def) = N_Access_Function_Definition then
1023 Check_For_Premature_Usage (Result_Definition (Def));
1026 end Check_For_Premature_Usage;
1030 Formals : constant List_Id := Parameter_Specifications (T_Def);
1033 Desig_Type : constant Entity_Id :=
1034 Create_Itype (E_Subprogram_Type, Parent (T_Def));
1036 -- Start of processing for Access_Subprogram_Declaration
1039 -- Associate the Itype node with the inner full-type declaration or
1040 -- subprogram spec. This is required to handle nested anonymous
1041 -- declarations. For example:
1044 -- (X : access procedure
1045 -- (Y : access procedure
1048 D_Ityp := Associated_Node_For_Itype (Desig_Type);
1049 while not (Nkind_In (D_Ityp, N_Full_Type_Declaration,
1050 N_Private_Type_Declaration,
1051 N_Private_Extension_Declaration,
1052 N_Procedure_Specification,
1053 N_Function_Specification)
1055 Nkind_In (D_Ityp, N_Object_Declaration,
1056 N_Object_Renaming_Declaration,
1057 N_Formal_Object_Declaration,
1058 N_Formal_Type_Declaration,
1059 N_Task_Type_Declaration,
1060 N_Protected_Type_Declaration))
1062 D_Ityp := Parent (D_Ityp);
1063 pragma Assert (D_Ityp /= Empty);
1066 Set_Associated_Node_For_Itype (Desig_Type, D_Ityp);
1068 if Nkind_In (D_Ityp, N_Procedure_Specification,
1069 N_Function_Specification)
1071 Set_Scope (Desig_Type, Scope (Defining_Entity (D_Ityp)));
1073 elsif Nkind_In (D_Ityp, N_Full_Type_Declaration,
1074 N_Object_Declaration,
1075 N_Object_Renaming_Declaration,
1076 N_Formal_Type_Declaration)
1078 Set_Scope (Desig_Type, Scope (Defining_Identifier (D_Ityp)));
1081 if Nkind (T_Def) = N_Access_Function_Definition then
1082 if Nkind (Result_Definition (T_Def)) = N_Access_Definition then
1084 Acc : constant Node_Id := Result_Definition (T_Def);
1087 if Present (Access_To_Subprogram_Definition (Acc))
1089 Protected_Present (Access_To_Subprogram_Definition (Acc))
1093 Replace_Anonymous_Access_To_Protected_Subprogram
1099 Access_Definition (T_Def, Result_Definition (T_Def)));
1104 Analyze (Result_Definition (T_Def));
1107 Typ : constant Entity_Id := Entity (Result_Definition (T_Def));
1110 -- If a null exclusion is imposed on the result type, then
1111 -- create a null-excluding itype (an access subtype) and use
1112 -- it as the function's Etype.
1114 if Is_Access_Type (Typ)
1115 and then Null_Exclusion_In_Return_Present (T_Def)
1117 Set_Etype (Desig_Type,
1118 Create_Null_Excluding_Itype
1120 Related_Nod => T_Def,
1121 Scope_Id => Current_Scope));
1124 if From_With_Type (Typ) then
1126 ("illegal use of incomplete type&",
1127 Result_Definition (T_Def), Typ);
1129 elsif Ekind (Current_Scope) = E_Package
1130 and then In_Private_Part (Current_Scope)
1132 if Ekind (Typ) = E_Incomplete_Type then
1133 Append_Elmt (Desig_Type, Private_Dependents (Typ));
1135 elsif Is_Class_Wide_Type (Typ)
1136 and then Ekind (Etype (Typ)) = E_Incomplete_Type
1139 (Desig_Type, Private_Dependents (Etype (Typ)));
1143 Set_Etype (Desig_Type, Typ);
1148 if not (Is_Type (Etype (Desig_Type))) then
1150 ("expect type in function specification",
1151 Result_Definition (T_Def));
1155 Set_Etype (Desig_Type, Standard_Void_Type);
1158 if Present (Formals) then
1159 Push_Scope (Desig_Type);
1161 -- A bit of a kludge here. These kludges will be removed when Itypes
1162 -- have proper parent pointers to their declarations???
1164 -- Kludge 1) Link defining_identifier of formals. Required by
1165 -- First_Formal to provide its functionality.
1171 F := First (Formals);
1172 while Present (F) loop
1173 if No (Parent (Defining_Identifier (F))) then
1174 Set_Parent (Defining_Identifier (F), F);
1181 Process_Formals (Formals, Parent (T_Def));
1183 -- Kludge 2) End_Scope requires that the parent pointer be set to
1184 -- something reasonable, but Itypes don't have parent pointers. So
1185 -- we set it and then unset it ???
1187 Set_Parent (Desig_Type, T_Name);
1189 Set_Parent (Desig_Type, Empty);
1192 -- Check for premature usage of the type being defined
1194 Check_For_Premature_Usage (T_Def);
1196 -- The return type and/or any parameter type may be incomplete. Mark
1197 -- the subprogram_type as depending on the incomplete type, so that
1198 -- it can be updated when the full type declaration is seen. This
1199 -- only applies to incomplete types declared in some enclosing scope,
1200 -- not to limited views from other packages.
1202 if Present (Formals) then
1203 Formal := First_Formal (Desig_Type);
1204 while Present (Formal) loop
1205 if Ekind (Formal) /= E_In_Parameter
1206 and then Nkind (T_Def) = N_Access_Function_Definition
1208 Error_Msg_N ("functions can only have IN parameters", Formal);
1211 if Ekind (Etype (Formal)) = E_Incomplete_Type
1212 and then In_Open_Scopes (Scope (Etype (Formal)))
1214 Append_Elmt (Desig_Type, Private_Dependents (Etype (Formal)));
1215 Set_Has_Delayed_Freeze (Desig_Type);
1218 Next_Formal (Formal);
1222 -- If the return type is incomplete, this is legal as long as the
1223 -- type is declared in the current scope and will be completed in
1224 -- it (rather than being part of limited view).
1226 if Ekind (Etype (Desig_Type)) = E_Incomplete_Type
1227 and then not Has_Delayed_Freeze (Desig_Type)
1228 and then In_Open_Scopes (Scope (Etype (Desig_Type)))
1230 Append_Elmt (Desig_Type, Private_Dependents (Etype (Desig_Type)));
1231 Set_Has_Delayed_Freeze (Desig_Type);
1234 Check_Delayed_Subprogram (Desig_Type);
1236 if Protected_Present (T_Def) then
1237 Set_Ekind (T_Name, E_Access_Protected_Subprogram_Type);
1238 Set_Convention (Desig_Type, Convention_Protected);
1240 Set_Ekind (T_Name, E_Access_Subprogram_Type);
1243 Set_Can_Use_Internal_Rep (T_Name, not Always_Compatible_Rep_On_Target);
1245 Set_Etype (T_Name, T_Name);
1246 Init_Size_Align (T_Name);
1247 Set_Directly_Designated_Type (T_Name, Desig_Type);
1249 -- Ada 2005 (AI-231): Propagate the null-excluding attribute
1251 Set_Can_Never_Be_Null (T_Name, Null_Exclusion_Present (T_Def));
1253 Check_Restriction (No_Access_Subprograms, T_Def);
1254 end Access_Subprogram_Declaration;
1256 ----------------------------
1257 -- Access_Type_Declaration --
1258 ----------------------------
1260 procedure Access_Type_Declaration (T : Entity_Id; Def : Node_Id) is
1261 S : constant Node_Id := Subtype_Indication (Def);
1262 P : constant Node_Id := Parent (Def);
1264 -- Check for permissible use of incomplete type
1266 if Nkind (S) /= N_Subtype_Indication then
1269 if Ekind (Root_Type (Entity (S))) = E_Incomplete_Type then
1270 Set_Directly_Designated_Type (T, Entity (S));
1272 Set_Directly_Designated_Type (T,
1273 Process_Subtype (S, P, T, 'P'));
1277 Set_Directly_Designated_Type (T,
1278 Process_Subtype (S, P, T, 'P'));
1281 if All_Present (Def) or Constant_Present (Def) then
1282 Set_Ekind (T, E_General_Access_Type);
1284 Set_Ekind (T, E_Access_Type);
1287 if Base_Type (Designated_Type (T)) = T then
1288 Error_Msg_N ("access type cannot designate itself", S);
1290 -- In Ada 2005, the type may have a limited view through some unit
1291 -- in its own context, allowing the following circularity that cannot
1292 -- be detected earlier
1294 elsif Is_Class_Wide_Type (Designated_Type (T))
1295 and then Etype (Designated_Type (T)) = T
1298 ("access type cannot designate its own classwide type", S);
1300 -- Clean up indication of tagged status to prevent cascaded errors
1302 Set_Is_Tagged_Type (T, False);
1307 -- If the type has appeared already in a with_type clause, it is
1308 -- frozen and the pointer size is already set. Else, initialize.
1310 if not From_With_Type (T) then
1311 Init_Size_Align (T);
1314 -- Note that Has_Task is always false, since the access type itself
1315 -- is not a task type. See Einfo for more description on this point.
1316 -- Exactly the same consideration applies to Has_Controlled_Component.
1318 Set_Has_Task (T, False);
1319 Set_Has_Controlled_Component (T, False);
1321 -- Initialize Associated_Final_Chain explicitly to Empty, to avoid
1322 -- problems where an incomplete view of this entity has been previously
1323 -- established by a limited with and an overlaid version of this field
1324 -- (Stored_Constraint) was initialized for the incomplete view.
1326 Set_Associated_Final_Chain (T, Empty);
1328 -- Ada 2005 (AI-231): Propagate the null-excluding and access-constant
1331 Set_Can_Never_Be_Null (T, Null_Exclusion_Present (Def));
1332 Set_Is_Access_Constant (T, Constant_Present (Def));
1333 end Access_Type_Declaration;
1335 ----------------------------------
1336 -- Add_Interface_Tag_Components --
1337 ----------------------------------
1339 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id) is
1340 Loc : constant Source_Ptr := Sloc (N);
1344 procedure Add_Tag (Iface : Entity_Id);
1345 -- Add tag for one of the progenitor interfaces
1351 procedure Add_Tag (Iface : Entity_Id) is
1358 pragma Assert (Is_Tagged_Type (Iface)
1359 and then Is_Interface (Iface));
1362 Make_Component_Definition (Loc,
1363 Aliased_Present => True,
1364 Subtype_Indication =>
1365 New_Occurrence_Of (RTE (RE_Interface_Tag), Loc));
1367 Tag := Make_Temporary (Loc, 'V');
1370 Make_Component_Declaration (Loc,
1371 Defining_Identifier => Tag,
1372 Component_Definition => Def);
1374 Analyze_Component_Declaration (Decl);
1376 Set_Analyzed (Decl);
1377 Set_Ekind (Tag, E_Component);
1379 Set_Is_Aliased (Tag);
1380 Set_Related_Type (Tag, Iface);
1381 Init_Component_Location (Tag);
1383 pragma Assert (Is_Frozen (Iface));
1385 Set_DT_Entry_Count (Tag,
1386 DT_Entry_Count (First_Entity (Iface)));
1388 if No (Last_Tag) then
1391 Insert_After (Last_Tag, Decl);
1396 -- If the ancestor has discriminants we need to give special support
1397 -- to store the offset_to_top value of the secondary dispatch tables.
1398 -- For this purpose we add a supplementary component just after the
1399 -- field that contains the tag associated with each secondary DT.
1401 if Typ /= Etype (Typ)
1402 and then Has_Discriminants (Etype (Typ))
1405 Make_Component_Definition (Loc,
1406 Subtype_Indication =>
1407 New_Occurrence_Of (RTE (RE_Storage_Offset), Loc));
1409 Offset := Make_Temporary (Loc, 'V');
1412 Make_Component_Declaration (Loc,
1413 Defining_Identifier => Offset,
1414 Component_Definition => Def);
1416 Analyze_Component_Declaration (Decl);
1418 Set_Analyzed (Decl);
1419 Set_Ekind (Offset, E_Component);
1420 Set_Is_Aliased (Offset);
1421 Set_Related_Type (Offset, Iface);
1422 Init_Component_Location (Offset);
1423 Insert_After (Last_Tag, Decl);
1434 -- Start of processing for Add_Interface_Tag_Components
1437 if not RTE_Available (RE_Interface_Tag) then
1439 ("(Ada 2005) interface types not supported by this run-time!",
1444 if Ekind (Typ) /= E_Record_Type
1445 or else (Is_Concurrent_Record_Type (Typ)
1446 and then Is_Empty_List (Abstract_Interface_List (Typ)))
1447 or else (not Is_Concurrent_Record_Type (Typ)
1448 and then No (Interfaces (Typ))
1449 and then Is_Empty_Elmt_List (Interfaces (Typ)))
1454 -- Find the current last tag
1456 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1457 Ext := Record_Extension_Part (Type_Definition (N));
1459 pragma Assert (Nkind (Type_Definition (N)) = N_Record_Definition);
1460 Ext := Type_Definition (N);
1465 if not (Present (Component_List (Ext))) then
1466 Set_Null_Present (Ext, False);
1468 Set_Component_List (Ext,
1469 Make_Component_List (Loc,
1470 Component_Items => L,
1471 Null_Present => False));
1473 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1474 L := Component_Items
1476 (Record_Extension_Part
1477 (Type_Definition (N))));
1479 L := Component_Items
1481 (Type_Definition (N)));
1484 -- Find the last tag component
1487 while Present (Comp) loop
1488 if Nkind (Comp) = N_Component_Declaration
1489 and then Is_Tag (Defining_Identifier (Comp))
1498 -- At this point L references the list of components and Last_Tag
1499 -- references the current last tag (if any). Now we add the tag
1500 -- corresponding with all the interfaces that are not implemented
1503 if Present (Interfaces (Typ)) then
1504 Elmt := First_Elmt (Interfaces (Typ));
1505 while Present (Elmt) loop
1506 Add_Tag (Node (Elmt));
1510 end Add_Interface_Tag_Components;
1512 -------------------------------------
1513 -- Add_Internal_Interface_Entities --
1514 -------------------------------------
1516 procedure Add_Internal_Interface_Entities (Tagged_Type : Entity_Id) is
1519 Iface_Elmt : Elmt_Id;
1520 Iface_Prim : Entity_Id;
1521 Ifaces_List : Elist_Id;
1522 New_Subp : Entity_Id := Empty;
1526 pragma Assert (Ada_Version >= Ada_05
1527 and then Is_Record_Type (Tagged_Type)
1528 and then Is_Tagged_Type (Tagged_Type)
1529 and then Has_Interfaces (Tagged_Type)
1530 and then not Is_Interface (Tagged_Type));
1532 Collect_Interfaces (Tagged_Type, Ifaces_List);
1534 Iface_Elmt := First_Elmt (Ifaces_List);
1535 while Present (Iface_Elmt) loop
1536 Iface := Node (Iface_Elmt);
1538 -- Exclude from this processing interfaces that are parents of
1539 -- Tagged_Type because their primitives are located in the primary
1540 -- dispatch table (and hence no auxiliary internal entities are
1541 -- required to handle secondary dispatch tables in such case).
1543 if not Is_Ancestor (Iface, Tagged_Type) then
1544 Elmt := First_Elmt (Primitive_Operations (Iface));
1545 while Present (Elmt) loop
1546 Iface_Prim := Node (Elmt);
1548 if not Is_Predefined_Dispatching_Operation (Iface_Prim) then
1550 Find_Primitive_Covering_Interface
1551 (Tagged_Type => Tagged_Type,
1552 Iface_Prim => Iface_Prim);
1556 -- In some rare cases, a name conflict may have kept the
1557 -- operation completely hidden. Look for it in the list
1558 -- of primitive operations of the type.
1563 El := First_Elmt (Primitive_Operations (Tagged_Type));
1564 while Present (El) loop
1566 exit when Is_Subprogram (Prim)
1567 and then Alias (Prim) = Iface_Prim;
1571 -- If the operation was not explicitly overridden, it
1572 -- should have been inherited as an abstract operation
1573 -- so Prim can not be Empty at this stage.
1576 raise Program_Error;
1582 (New_Subp => New_Subp,
1583 Parent_Subp => Iface_Prim,
1584 Derived_Type => Tagged_Type,
1585 Parent_Type => Iface);
1587 -- Ada 2005 (AI-251): Decorate internal entity Iface_Subp
1588 -- associated with interface types. These entities are
1589 -- only registered in the list of primitives of its
1590 -- corresponding tagged type because they are only used
1591 -- to fill the contents of the secondary dispatch tables.
1592 -- Therefore they are removed from the homonym chains.
1594 Set_Is_Hidden (New_Subp);
1595 Set_Is_Internal (New_Subp);
1596 Set_Alias (New_Subp, Prim);
1597 Set_Is_Abstract_Subprogram (New_Subp,
1598 Is_Abstract_Subprogram (Prim));
1599 Set_Interface_Alias (New_Subp, Iface_Prim);
1601 -- Internal entities associated with interface types are
1602 -- only registered in the list of primitives of the tagged
1603 -- type. They are only used to fill the contents of the
1604 -- secondary dispatch tables. Therefore they are not needed
1605 -- in the homonym chains.
1607 Remove_Homonym (New_Subp);
1609 -- Hidden entities associated with interfaces must have set
1610 -- the Has_Delay_Freeze attribute to ensure that, in case of
1611 -- locally defined tagged types (or compiling with static
1612 -- dispatch tables generation disabled) the corresponding
1613 -- entry of the secondary dispatch table is filled when
1614 -- such an entity is frozen.
1616 Set_Has_Delayed_Freeze (New_Subp);
1623 Next_Elmt (Iface_Elmt);
1625 end Add_Internal_Interface_Entities;
1627 -----------------------------------
1628 -- Analyze_Component_Declaration --
1629 -----------------------------------
1631 procedure Analyze_Component_Declaration (N : Node_Id) is
1632 Id : constant Entity_Id := Defining_Identifier (N);
1633 E : constant Node_Id := Expression (N);
1637 function Contains_POC (Constr : Node_Id) return Boolean;
1638 -- Determines whether a constraint uses the discriminant of a record
1639 -- type thus becoming a per-object constraint (POC).
1641 function Is_Known_Limited (Typ : Entity_Id) return Boolean;
1642 -- Typ is the type of the current component, check whether this type is
1643 -- a limited type. Used to validate declaration against that of
1644 -- enclosing record.
1650 function Contains_POC (Constr : Node_Id) return Boolean is
1652 -- Prevent cascaded errors
1654 if Error_Posted (Constr) then
1658 case Nkind (Constr) is
1659 when N_Attribute_Reference =>
1661 Attribute_Name (Constr) = Name_Access
1662 and then Prefix (Constr) = Scope (Entity (Prefix (Constr)));
1664 when N_Discriminant_Association =>
1665 return Denotes_Discriminant (Expression (Constr));
1667 when N_Identifier =>
1668 return Denotes_Discriminant (Constr);
1670 when N_Index_Or_Discriminant_Constraint =>
1675 IDC := First (Constraints (Constr));
1676 while Present (IDC) loop
1678 -- One per-object constraint is sufficient
1680 if Contains_POC (IDC) then
1691 return Denotes_Discriminant (Low_Bound (Constr))
1693 Denotes_Discriminant (High_Bound (Constr));
1695 when N_Range_Constraint =>
1696 return Denotes_Discriminant (Range_Expression (Constr));
1704 ----------------------
1705 -- Is_Known_Limited --
1706 ----------------------
1708 function Is_Known_Limited (Typ : Entity_Id) return Boolean is
1709 P : constant Entity_Id := Etype (Typ);
1710 R : constant Entity_Id := Root_Type (Typ);
1713 if Is_Limited_Record (Typ) then
1716 -- If the root type is limited (and not a limited interface)
1717 -- so is the current type
1719 elsif Is_Limited_Record (R)
1721 (not Is_Interface (R)
1722 or else not Is_Limited_Interface (R))
1726 -- Else the type may have a limited interface progenitor, but a
1727 -- limited record parent.
1730 and then Is_Limited_Record (P)
1737 end Is_Known_Limited;
1739 -- Start of processing for Analyze_Component_Declaration
1742 Generate_Definition (Id);
1745 if Present (Subtype_Indication (Component_Definition (N))) then
1746 T := Find_Type_Of_Object
1747 (Subtype_Indication (Component_Definition (N)), N);
1749 -- Ada 2005 (AI-230): Access Definition case
1752 pragma Assert (Present
1753 (Access_Definition (Component_Definition (N))));
1755 T := Access_Definition
1757 N => Access_Definition (Component_Definition (N)));
1758 Set_Is_Local_Anonymous_Access (T);
1760 -- Ada 2005 (AI-254)
1762 if Present (Access_To_Subprogram_Definition
1763 (Access_Definition (Component_Definition (N))))
1764 and then Protected_Present (Access_To_Subprogram_Definition
1766 (Component_Definition (N))))
1768 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1772 -- If the subtype is a constrained subtype of the enclosing record,
1773 -- (which must have a partial view) the back-end does not properly
1774 -- handle the recursion. Rewrite the component declaration with an
1775 -- explicit subtype indication, which is acceptable to Gigi. We can copy
1776 -- the tree directly because side effects have already been removed from
1777 -- discriminant constraints.
1779 if Ekind (T) = E_Access_Subtype
1780 and then Is_Entity_Name (Subtype_Indication (Component_Definition (N)))
1781 and then Comes_From_Source (T)
1782 and then Nkind (Parent (T)) = N_Subtype_Declaration
1783 and then Etype (Directly_Designated_Type (T)) = Current_Scope
1786 (Subtype_Indication (Component_Definition (N)),
1787 New_Copy_Tree (Subtype_Indication (Parent (T))));
1788 T := Find_Type_Of_Object
1789 (Subtype_Indication (Component_Definition (N)), N);
1792 -- If the component declaration includes a default expression, then we
1793 -- check that the component is not of a limited type (RM 3.7(5)),
1794 -- and do the special preanalysis of the expression (see section on
1795 -- "Handling of Default and Per-Object Expressions" in the spec of
1799 Preanalyze_Spec_Expression (E, T);
1800 Check_Initialization (T, E);
1802 if Ada_Version >= Ada_05
1803 and then Ekind (T) = E_Anonymous_Access_Type
1804 and then Etype (E) /= Any_Type
1806 -- Check RM 3.9.2(9): "if the expected type for an expression is
1807 -- an anonymous access-to-specific tagged type, then the object
1808 -- designated by the expression shall not be dynamically tagged
1809 -- unless it is a controlling operand in a call on a dispatching
1812 if Is_Tagged_Type (Directly_Designated_Type (T))
1814 Ekind (Directly_Designated_Type (T)) /= E_Class_Wide_Type
1816 Ekind (Directly_Designated_Type (Etype (E))) =
1820 ("access to specific tagged type required (RM 3.9.2(9))", E);
1823 -- (Ada 2005: AI-230): Accessibility check for anonymous
1826 if Type_Access_Level (Etype (E)) > Type_Access_Level (T) then
1828 ("expression has deeper access level than component " &
1829 "(RM 3.10.2 (12.2))", E);
1832 -- The initialization expression is a reference to an access
1833 -- discriminant. The type of the discriminant is always deeper
1834 -- than any access type.
1836 if Ekind (Etype (E)) = E_Anonymous_Access_Type
1837 and then Is_Entity_Name (E)
1838 and then Ekind (Entity (E)) = E_In_Parameter
1839 and then Present (Discriminal_Link (Entity (E)))
1842 ("discriminant has deeper accessibility level than target",
1848 -- The parent type may be a private view with unknown discriminants,
1849 -- and thus unconstrained. Regular components must be constrained.
1851 if Is_Indefinite_Subtype (T) and then Chars (Id) /= Name_uParent then
1852 if Is_Class_Wide_Type (T) then
1854 ("class-wide subtype with unknown discriminants" &
1855 " in component declaration",
1856 Subtype_Indication (Component_Definition (N)));
1859 ("unconstrained subtype in component declaration",
1860 Subtype_Indication (Component_Definition (N)));
1863 -- Components cannot be abstract, except for the special case of
1864 -- the _Parent field (case of extending an abstract tagged type)
1866 elsif Is_Abstract_Type (T) and then Chars (Id) /= Name_uParent then
1867 Error_Msg_N ("type of a component cannot be abstract", N);
1871 Set_Is_Aliased (Id, Aliased_Present (Component_Definition (N)));
1873 -- The component declaration may have a per-object constraint, set
1874 -- the appropriate flag in the defining identifier of the subtype.
1876 if Present (Subtype_Indication (Component_Definition (N))) then
1878 Sindic : constant Node_Id :=
1879 Subtype_Indication (Component_Definition (N));
1881 if Nkind (Sindic) = N_Subtype_Indication
1882 and then Present (Constraint (Sindic))
1883 and then Contains_POC (Constraint (Sindic))
1885 Set_Has_Per_Object_Constraint (Id);
1890 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
1891 -- out some static checks.
1893 if Ada_Version >= Ada_05
1894 and then Can_Never_Be_Null (T)
1896 Null_Exclusion_Static_Checks (N);
1899 -- If this component is private (or depends on a private type), flag the
1900 -- record type to indicate that some operations are not available.
1902 P := Private_Component (T);
1906 -- Check for circular definitions
1908 if P = Any_Type then
1909 Set_Etype (Id, Any_Type);
1911 -- There is a gap in the visibility of operations only if the
1912 -- component type is not defined in the scope of the record type.
1914 elsif Scope (P) = Scope (Current_Scope) then
1917 elsif Is_Limited_Type (P) then
1918 Set_Is_Limited_Composite (Current_Scope);
1921 Set_Is_Private_Composite (Current_Scope);
1926 and then Is_Limited_Type (T)
1927 and then Chars (Id) /= Name_uParent
1928 and then Is_Tagged_Type (Current_Scope)
1930 if Is_Derived_Type (Current_Scope)
1931 and then not Is_Known_Limited (Current_Scope)
1934 ("extension of nonlimited type cannot have limited components",
1937 if Is_Interface (Root_Type (Current_Scope)) then
1939 ("\limitedness is not inherited from limited interface", N);
1940 Error_Msg_N ("\add LIMITED to type indication", N);
1943 Explain_Limited_Type (T, N);
1944 Set_Etype (Id, Any_Type);
1945 Set_Is_Limited_Composite (Current_Scope, False);
1947 elsif not Is_Derived_Type (Current_Scope)
1948 and then not Is_Limited_Record (Current_Scope)
1949 and then not Is_Concurrent_Type (Current_Scope)
1952 ("nonlimited tagged type cannot have limited components", N);
1953 Explain_Limited_Type (T, N);
1954 Set_Etype (Id, Any_Type);
1955 Set_Is_Limited_Composite (Current_Scope, False);
1959 Set_Original_Record_Component (Id, Id);
1960 end Analyze_Component_Declaration;
1962 --------------------------
1963 -- Analyze_Declarations --
1964 --------------------------
1966 procedure Analyze_Declarations (L : List_Id) is
1968 Freeze_From : Entity_Id := Empty;
1969 Next_Node : Node_Id;
1972 -- Adjust D not to include implicit label declarations, since these
1973 -- have strange Sloc values that result in elaboration check problems.
1974 -- (They have the sloc of the label as found in the source, and that
1975 -- is ahead of the current declarative part).
1981 procedure Adjust_D is
1983 while Present (Prev (D))
1984 and then Nkind (D) = N_Implicit_Label_Declaration
1990 -- Start of processing for Analyze_Declarations
1994 while Present (D) loop
1996 -- Complete analysis of declaration
1999 Next_Node := Next (D);
2001 if No (Freeze_From) then
2002 Freeze_From := First_Entity (Current_Scope);
2005 -- At the end of a declarative part, freeze remaining entities
2006 -- declared in it. The end of the visible declarations of package
2007 -- specification is not the end of a declarative part if private
2008 -- declarations are present. The end of a package declaration is a
2009 -- freezing point only if it a library package. A task definition or
2010 -- protected type definition is not a freeze point either. Finally,
2011 -- we do not freeze entities in generic scopes, because there is no
2012 -- code generated for them and freeze nodes will be generated for
2015 -- The end of a package instantiation is not a freeze point, but
2016 -- for now we make it one, because the generic body is inserted
2017 -- (currently) immediately after. Generic instantiations will not
2018 -- be a freeze point once delayed freezing of bodies is implemented.
2019 -- (This is needed in any case for early instantiations ???).
2021 if No (Next_Node) then
2022 if Nkind_In (Parent (L), N_Component_List,
2024 N_Protected_Definition)
2028 elsif Nkind (Parent (L)) /= N_Package_Specification then
2029 if Nkind (Parent (L)) = N_Package_Body then
2030 Freeze_From := First_Entity (Current_Scope);
2034 Freeze_All (Freeze_From, D);
2035 Freeze_From := Last_Entity (Current_Scope);
2037 elsif Scope (Current_Scope) /= Standard_Standard
2038 and then not Is_Child_Unit (Current_Scope)
2039 and then No (Generic_Parent (Parent (L)))
2043 elsif L /= Visible_Declarations (Parent (L))
2044 or else No (Private_Declarations (Parent (L)))
2045 or else Is_Empty_List (Private_Declarations (Parent (L)))
2048 Freeze_All (Freeze_From, D);
2049 Freeze_From := Last_Entity (Current_Scope);
2052 -- If next node is a body then freeze all types before the body.
2053 -- An exception occurs for some expander-generated bodies. If these
2054 -- are generated at places where in general language rules would not
2055 -- allow a freeze point, then we assume that the expander has
2056 -- explicitly checked that all required types are properly frozen,
2057 -- and we do not cause general freezing here. This special circuit
2058 -- is used when the encountered body is marked as having already
2061 -- In all other cases (bodies that come from source, and expander
2062 -- generated bodies that have not been analyzed yet), freeze all
2063 -- types now. Note that in the latter case, the expander must take
2064 -- care to attach the bodies at a proper place in the tree so as to
2065 -- not cause unwanted freezing at that point.
2067 elsif not Analyzed (Next_Node)
2068 and then (Nkind_In (Next_Node, N_Subprogram_Body,
2074 Nkind (Next_Node) in N_Body_Stub)
2077 Freeze_All (Freeze_From, D);
2078 Freeze_From := Last_Entity (Current_Scope);
2083 end Analyze_Declarations;
2085 ----------------------------------
2086 -- Analyze_Incomplete_Type_Decl --
2087 ----------------------------------
2089 procedure Analyze_Incomplete_Type_Decl (N : Node_Id) is
2090 F : constant Boolean := Is_Pure (Current_Scope);
2094 Generate_Definition (Defining_Identifier (N));
2096 -- Process an incomplete declaration. The identifier must not have been
2097 -- declared already in the scope. However, an incomplete declaration may
2098 -- appear in the private part of a package, for a private type that has
2099 -- already been declared.
2101 -- In this case, the discriminants (if any) must match
2103 T := Find_Type_Name (N);
2105 Set_Ekind (T, E_Incomplete_Type);
2106 Init_Size_Align (T);
2107 Set_Is_First_Subtype (T, True);
2110 -- Ada 2005 (AI-326): Minimum decoration to give support to tagged
2111 -- incomplete types.
2113 if Tagged_Present (N) then
2114 Set_Is_Tagged_Type (T);
2115 Make_Class_Wide_Type (T);
2116 Set_Primitive_Operations (T, New_Elmt_List);
2121 Set_Stored_Constraint (T, No_Elist);
2123 if Present (Discriminant_Specifications (N)) then
2124 Process_Discriminants (N);
2129 -- If the type has discriminants, non-trivial subtypes may be
2130 -- declared before the full view of the type. The full views of those
2131 -- subtypes will be built after the full view of the type.
2133 Set_Private_Dependents (T, New_Elmt_List);
2135 end Analyze_Incomplete_Type_Decl;
2137 -----------------------------------
2138 -- Analyze_Interface_Declaration --
2139 -----------------------------------
2141 procedure Analyze_Interface_Declaration (T : Entity_Id; Def : Node_Id) is
2142 CW : constant Entity_Id := Class_Wide_Type (T);
2145 Set_Is_Tagged_Type (T);
2147 Set_Is_Limited_Record (T, Limited_Present (Def)
2148 or else Task_Present (Def)
2149 or else Protected_Present (Def)
2150 or else Synchronized_Present (Def));
2152 -- Type is abstract if full declaration carries keyword, or if previous
2153 -- partial view did.
2155 Set_Is_Abstract_Type (T);
2156 Set_Is_Interface (T);
2158 -- Type is a limited interface if it includes the keyword limited, task,
2159 -- protected, or synchronized.
2161 Set_Is_Limited_Interface
2162 (T, Limited_Present (Def)
2163 or else Protected_Present (Def)
2164 or else Synchronized_Present (Def)
2165 or else Task_Present (Def));
2167 Set_Is_Protected_Interface (T, Protected_Present (Def));
2168 Set_Is_Task_Interface (T, Task_Present (Def));
2170 -- Type is a synchronized interface if it includes the keyword task,
2171 -- protected, or synchronized.
2173 Set_Is_Synchronized_Interface
2174 (T, Synchronized_Present (Def)
2175 or else Protected_Present (Def)
2176 or else Task_Present (Def));
2178 Set_Interfaces (T, New_Elmt_List);
2179 Set_Primitive_Operations (T, New_Elmt_List);
2181 -- Complete the decoration of the class-wide entity if it was already
2182 -- built (i.e. during the creation of the limited view)
2184 if Present (CW) then
2185 Set_Is_Interface (CW);
2186 Set_Is_Limited_Interface (CW, Is_Limited_Interface (T));
2187 Set_Is_Protected_Interface (CW, Is_Protected_Interface (T));
2188 Set_Is_Synchronized_Interface (CW, Is_Synchronized_Interface (T));
2189 Set_Is_Task_Interface (CW, Is_Task_Interface (T));
2192 -- Check runtime support for synchronized interfaces
2194 if VM_Target = No_VM
2195 and then (Is_Task_Interface (T)
2196 or else Is_Protected_Interface (T)
2197 or else Is_Synchronized_Interface (T))
2198 and then not RTE_Available (RE_Select_Specific_Data)
2200 Error_Msg_CRT ("synchronized interfaces", T);
2202 end Analyze_Interface_Declaration;
2204 -----------------------------
2205 -- Analyze_Itype_Reference --
2206 -----------------------------
2208 -- Nothing to do. This node is placed in the tree only for the benefit of
2209 -- back end processing, and has no effect on the semantic processing.
2211 procedure Analyze_Itype_Reference (N : Node_Id) is
2213 pragma Assert (Is_Itype (Itype (N)));
2215 end Analyze_Itype_Reference;
2217 --------------------------------
2218 -- Analyze_Number_Declaration --
2219 --------------------------------
2221 procedure Analyze_Number_Declaration (N : Node_Id) is
2222 Id : constant Entity_Id := Defining_Identifier (N);
2223 E : constant Node_Id := Expression (N);
2225 Index : Interp_Index;
2229 Generate_Definition (Id);
2232 -- This is an optimization of a common case of an integer literal
2234 if Nkind (E) = N_Integer_Literal then
2235 Set_Is_Static_Expression (E, True);
2236 Set_Etype (E, Universal_Integer);
2238 Set_Etype (Id, Universal_Integer);
2239 Set_Ekind (Id, E_Named_Integer);
2240 Set_Is_Frozen (Id, True);
2244 Set_Is_Pure (Id, Is_Pure (Current_Scope));
2246 -- Process expression, replacing error by integer zero, to avoid
2247 -- cascaded errors or aborts further along in the processing
2249 -- Replace Error by integer zero, which seems least likely to
2250 -- cause cascaded errors.
2253 Rewrite (E, Make_Integer_Literal (Sloc (E), Uint_0));
2254 Set_Error_Posted (E);
2259 -- Verify that the expression is static and numeric. If
2260 -- the expression is overloaded, we apply the preference
2261 -- rule that favors root numeric types.
2263 if not Is_Overloaded (E) then
2269 Get_First_Interp (E, Index, It);
2270 while Present (It.Typ) loop
2271 if (Is_Integer_Type (It.Typ)
2272 or else Is_Real_Type (It.Typ))
2273 and then (Scope (Base_Type (It.Typ))) = Standard_Standard
2275 if T = Any_Type then
2278 elsif It.Typ = Universal_Real
2279 or else It.Typ = Universal_Integer
2281 -- Choose universal interpretation over any other
2288 Get_Next_Interp (Index, It);
2292 if Is_Integer_Type (T) then
2294 Set_Etype (Id, Universal_Integer);
2295 Set_Ekind (Id, E_Named_Integer);
2297 elsif Is_Real_Type (T) then
2299 -- Because the real value is converted to universal_real, this is a
2300 -- legal context for a universal fixed expression.
2302 if T = Universal_Fixed then
2304 Loc : constant Source_Ptr := Sloc (N);
2305 Conv : constant Node_Id := Make_Type_Conversion (Loc,
2307 New_Occurrence_Of (Universal_Real, Loc),
2308 Expression => Relocate_Node (E));
2315 elsif T = Any_Fixed then
2316 Error_Msg_N ("illegal context for mixed mode operation", E);
2318 -- Expression is of the form : universal_fixed * integer. Try to
2319 -- resolve as universal_real.
2321 T := Universal_Real;
2326 Set_Etype (Id, Universal_Real);
2327 Set_Ekind (Id, E_Named_Real);
2330 Wrong_Type (E, Any_Numeric);
2334 Set_Ekind (Id, E_Constant);
2335 Set_Never_Set_In_Source (Id, True);
2336 Set_Is_True_Constant (Id, True);
2340 if Nkind_In (E, N_Integer_Literal, N_Real_Literal) then
2341 Set_Etype (E, Etype (Id));
2344 if not Is_OK_Static_Expression (E) then
2345 Flag_Non_Static_Expr
2346 ("non-static expression used in number declaration!", E);
2347 Rewrite (E, Make_Integer_Literal (Sloc (N), 1));
2348 Set_Etype (E, Any_Type);
2350 end Analyze_Number_Declaration;
2352 --------------------------------
2353 -- Analyze_Object_Declaration --
2354 --------------------------------
2356 procedure Analyze_Object_Declaration (N : Node_Id) is
2357 Loc : constant Source_Ptr := Sloc (N);
2358 Id : constant Entity_Id := Defining_Identifier (N);
2362 E : Node_Id := Expression (N);
2363 -- E is set to Expression (N) throughout this routine. When
2364 -- Expression (N) is modified, E is changed accordingly.
2366 Prev_Entity : Entity_Id := Empty;
2368 function Count_Tasks (T : Entity_Id) return Uint;
2369 -- This function is called when a non-generic library level object of a
2370 -- task type is declared. Its function is to count the static number of
2371 -- tasks declared within the type (it is only called if Has_Tasks is set
2372 -- for T). As a side effect, if an array of tasks with non-static bounds
2373 -- or a variant record type is encountered, Check_Restrictions is called
2374 -- indicating the count is unknown.
2380 function Count_Tasks (T : Entity_Id) return Uint is
2386 if Is_Task_Type (T) then
2389 elsif Is_Record_Type (T) then
2390 if Has_Discriminants (T) then
2391 Check_Restriction (Max_Tasks, N);
2396 C := First_Component (T);
2397 while Present (C) loop
2398 V := V + Count_Tasks (Etype (C));
2405 elsif Is_Array_Type (T) then
2406 X := First_Index (T);
2407 V := Count_Tasks (Component_Type (T));
2408 while Present (X) loop
2411 if not Is_Static_Subtype (C) then
2412 Check_Restriction (Max_Tasks, N);
2415 V := V * (UI_Max (Uint_0,
2416 Expr_Value (Type_High_Bound (C)) -
2417 Expr_Value (Type_Low_Bound (C)) + Uint_1));
2430 -- Start of processing for Analyze_Object_Declaration
2433 -- There are three kinds of implicit types generated by an
2434 -- object declaration:
2436 -- 1. Those for generated by the original Object Definition
2438 -- 2. Those generated by the Expression
2440 -- 3. Those used to constrained the Object Definition with the
2441 -- expression constraints when it is unconstrained
2443 -- They must be generated in this order to avoid order of elaboration
2444 -- issues. Thus the first step (after entering the name) is to analyze
2445 -- the object definition.
2447 if Constant_Present (N) then
2448 Prev_Entity := Current_Entity_In_Scope (Id);
2450 if Present (Prev_Entity)
2452 -- If the homograph is an implicit subprogram, it is overridden
2453 -- by the current declaration.
2455 ((Is_Overloadable (Prev_Entity)
2456 and then Is_Inherited_Operation (Prev_Entity))
2458 -- The current object is a discriminal generated for an entry
2459 -- family index. Even though the index is a constant, in this
2460 -- particular context there is no true constant redeclaration.
2461 -- Enter_Name will handle the visibility.
2464 (Is_Discriminal (Id)
2465 and then Ekind (Discriminal_Link (Id)) =
2466 E_Entry_Index_Parameter)
2468 -- The current object is the renaming for a generic declared
2469 -- within the instance.
2472 (Ekind (Prev_Entity) = E_Package
2473 and then Nkind (Parent (Prev_Entity)) =
2474 N_Package_Renaming_Declaration
2475 and then not Comes_From_Source (Prev_Entity)
2476 and then Is_Generic_Instance (Renamed_Entity (Prev_Entity))))
2478 Prev_Entity := Empty;
2482 if Present (Prev_Entity) then
2483 Constant_Redeclaration (Id, N, T);
2485 Generate_Reference (Prev_Entity, Id, 'c');
2486 Set_Completion_Referenced (Id);
2488 if Error_Posted (N) then
2490 -- Type mismatch or illegal redeclaration, Do not analyze
2491 -- expression to avoid cascaded errors.
2493 T := Find_Type_Of_Object (Object_Definition (N), N);
2495 Set_Ekind (Id, E_Variable);
2499 -- In the normal case, enter identifier at the start to catch premature
2500 -- usage in the initialization expression.
2503 Generate_Definition (Id);
2506 Mark_Coextensions (N, Object_Definition (N));
2508 T := Find_Type_Of_Object (Object_Definition (N), N);
2510 if Nkind (Object_Definition (N)) = N_Access_Definition
2512 (Access_To_Subprogram_Definition (Object_Definition (N)))
2513 and then Protected_Present
2514 (Access_To_Subprogram_Definition (Object_Definition (N)))
2516 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
2519 if Error_Posted (Id) then
2521 Set_Ekind (Id, E_Variable);
2526 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
2527 -- out some static checks
2529 if Ada_Version >= Ada_05
2530 and then Can_Never_Be_Null (T)
2532 -- In case of aggregates we must also take care of the correct
2533 -- initialization of nested aggregates bug this is done at the
2534 -- point of the analysis of the aggregate (see sem_aggr.adb)
2536 if Present (Expression (N))
2537 and then Nkind (Expression (N)) = N_Aggregate
2543 Save_Typ : constant Entity_Id := Etype (Id);
2545 Set_Etype (Id, T); -- Temp. decoration for static checks
2546 Null_Exclusion_Static_Checks (N);
2547 Set_Etype (Id, Save_Typ);
2552 Set_Is_Pure (Id, Is_Pure (Current_Scope));
2554 -- If deferred constant, make sure context is appropriate. We detect
2555 -- a deferred constant as a constant declaration with no expression.
2556 -- A deferred constant can appear in a package body if its completion
2557 -- is by means of an interface pragma.
2559 if Constant_Present (N)
2562 -- A deferred constant may appear in the declarative part of the
2563 -- following constructs:
2567 -- extended return statements
2570 -- subprogram bodies
2573 -- When declared inside a package spec, a deferred constant must be
2574 -- completed by a full constant declaration or pragma Import. In all
2575 -- other cases, the only proper completion is pragma Import. Extended
2576 -- return statements are flagged as invalid contexts because they do
2577 -- not have a declarative part and so cannot accommodate the pragma.
2579 if Ekind (Current_Scope) = E_Return_Statement then
2581 ("invalid context for deferred constant declaration (RM 7.4)",
2584 ("\declaration requires an initialization expression",
2586 Set_Constant_Present (N, False);
2588 -- In Ada 83, deferred constant must be of private type
2590 elsif not Is_Private_Type (T) then
2591 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
2593 ("(Ada 83) deferred constant must be private type", N);
2597 -- If not a deferred constant, then object declaration freezes its type
2600 Check_Fully_Declared (T, N);
2601 Freeze_Before (N, T);
2604 -- If the object was created by a constrained array definition, then
2605 -- set the link in both the anonymous base type and anonymous subtype
2606 -- that are built to represent the array type to point to the object.
2608 if Nkind (Object_Definition (Declaration_Node (Id))) =
2609 N_Constrained_Array_Definition
2611 Set_Related_Array_Object (T, Id);
2612 Set_Related_Array_Object (Base_Type (T), Id);
2615 -- Special checks for protected objects not at library level
2617 if Is_Protected_Type (T)
2618 and then not Is_Library_Level_Entity (Id)
2620 Check_Restriction (No_Local_Protected_Objects, Id);
2622 -- Protected objects with interrupt handlers must be at library level
2624 -- Ada 2005: this test is not needed (and the corresponding clause
2625 -- in the RM is removed) because accessibility checks are sufficient
2626 -- to make handlers not at the library level illegal.
2628 if Has_Interrupt_Handler (T)
2629 and then Ada_Version < Ada_05
2632 ("interrupt object can only be declared at library level", Id);
2636 -- The actual subtype of the object is the nominal subtype, unless
2637 -- the nominal one is unconstrained and obtained from the expression.
2641 -- Process initialization expression if present and not in error
2643 if Present (E) and then E /= Error then
2645 -- Generate an error in case of CPP class-wide object initialization.
2646 -- Required because otherwise the expansion of the class-wide
2647 -- assignment would try to use 'size to initialize the object
2648 -- (primitive that is not available in CPP tagged types).
2650 if Is_Class_Wide_Type (Act_T)
2652 (Is_CPP_Class (Root_Type (Etype (Act_T)))
2654 (Present (Full_View (Root_Type (Etype (Act_T))))
2656 Is_CPP_Class (Full_View (Root_Type (Etype (Act_T))))))
2659 ("predefined assignment not available for 'C'P'P tagged types",
2663 Mark_Coextensions (N, E);
2666 -- In case of errors detected in the analysis of the expression,
2667 -- decorate it with the expected type to avoid cascaded errors
2669 if No (Etype (E)) then
2673 -- If an initialization expression is present, then we set the
2674 -- Is_True_Constant flag. It will be reset if this is a variable
2675 -- and it is indeed modified.
2677 Set_Is_True_Constant (Id, True);
2679 -- If we are analyzing a constant declaration, set its completion
2680 -- flag after analyzing and resolving the expression.
2682 if Constant_Present (N) then
2683 Set_Has_Completion (Id);
2686 -- Set type and resolve (type may be overridden later on)
2691 -- If E is null and has been replaced by an N_Raise_Constraint_Error
2692 -- node (which was marked already-analyzed), we need to set the type
2693 -- to something other than Any_Access in order to keep gigi happy.
2695 if Etype (E) = Any_Access then
2699 -- If the object is an access to variable, the initialization
2700 -- expression cannot be an access to constant.
2702 if Is_Access_Type (T)
2703 and then not Is_Access_Constant (T)
2704 and then Is_Access_Type (Etype (E))
2705 and then Is_Access_Constant (Etype (E))
2708 ("access to variable cannot be initialized "
2709 & "with an access-to-constant expression", E);
2712 if not Assignment_OK (N) then
2713 Check_Initialization (T, E);
2716 Check_Unset_Reference (E);
2718 -- If this is a variable, then set current value. If this is a
2719 -- declared constant of a scalar type with a static expression,
2720 -- indicate that it is always valid.
2722 if not Constant_Present (N) then
2723 if Compile_Time_Known_Value (E) then
2724 Set_Current_Value (Id, E);
2727 elsif Is_Scalar_Type (T)
2728 and then Is_OK_Static_Expression (E)
2730 Set_Is_Known_Valid (Id);
2733 -- Deal with setting of null flags
2735 if Is_Access_Type (T) then
2736 if Known_Non_Null (E) then
2737 Set_Is_Known_Non_Null (Id, True);
2738 elsif Known_Null (E)
2739 and then not Can_Never_Be_Null (Id)
2741 Set_Is_Known_Null (Id, True);
2745 -- Check incorrect use of dynamically tagged expressions.
2747 if Is_Tagged_Type (T) then
2748 Check_Dynamically_Tagged_Expression
2754 Apply_Scalar_Range_Check (E, T);
2755 Apply_Static_Length_Check (E, T);
2758 -- If the No_Streams restriction is set, check that the type of the
2759 -- object is not, and does not contain, any subtype derived from
2760 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
2761 -- Has_Stream just for efficiency reasons. There is no point in
2762 -- spending time on a Has_Stream check if the restriction is not set.
2764 if Restrictions.Set (No_Streams) then
2765 if Has_Stream (T) then
2766 Check_Restriction (No_Streams, N);
2770 -- Case of unconstrained type
2772 if Is_Indefinite_Subtype (T) then
2774 -- Nothing to do in deferred constant case
2776 if Constant_Present (N) and then No (E) then
2779 -- Case of no initialization present
2782 if No_Initialization (N) then
2785 elsif Is_Class_Wide_Type (T) then
2787 ("initialization required in class-wide declaration ", N);
2791 ("unconstrained subtype not allowed (need initialization)",
2792 Object_Definition (N));
2794 if Is_Record_Type (T) and then Has_Discriminants (T) then
2796 ("\provide initial value or explicit discriminant values",
2797 Object_Definition (N));
2800 ("\or give default discriminant values for type&",
2801 Object_Definition (N), T);
2803 elsif Is_Array_Type (T) then
2805 ("\provide initial value or explicit array bounds",
2806 Object_Definition (N));
2810 -- Case of initialization present but in error. Set initial
2811 -- expression as absent (but do not make above complaints)
2813 elsif E = Error then
2814 Set_Expression (N, Empty);
2817 -- Case of initialization present
2820 -- Not allowed in Ada 83
2822 if not Constant_Present (N) then
2823 if Ada_Version = Ada_83
2824 and then Comes_From_Source (Object_Definition (N))
2827 ("(Ada 83) unconstrained variable not allowed",
2828 Object_Definition (N));
2832 -- Now we constrain the variable from the initializing expression
2834 -- If the expression is an aggregate, it has been expanded into
2835 -- individual assignments. Retrieve the actual type from the
2836 -- expanded construct.
2838 if Is_Array_Type (T)
2839 and then No_Initialization (N)
2840 and then Nkind (Original_Node (E)) = N_Aggregate
2844 -- In case of class-wide interface object declarations we delay
2845 -- the generation of the equivalent record type declarations until
2846 -- its expansion because there are cases in they are not required.
2848 elsif Is_Interface (T) then
2852 Expand_Subtype_From_Expr (N, T, Object_Definition (N), E);
2853 Act_T := Find_Type_Of_Object (Object_Definition (N), N);
2856 Set_Is_Constr_Subt_For_U_Nominal (Act_T);
2858 if Aliased_Present (N) then
2859 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
2862 Freeze_Before (N, Act_T);
2863 Freeze_Before (N, T);
2866 elsif Is_Array_Type (T)
2867 and then No_Initialization (N)
2868 and then Nkind (Original_Node (E)) = N_Aggregate
2870 if not Is_Entity_Name (Object_Definition (N)) then
2872 Check_Compile_Time_Size (Act_T);
2874 if Aliased_Present (N) then
2875 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
2879 -- When the given object definition and the aggregate are specified
2880 -- independently, and their lengths might differ do a length check.
2881 -- This cannot happen if the aggregate is of the form (others =>...)
2883 if not Is_Constrained (T) then
2886 elsif Nkind (E) = N_Raise_Constraint_Error then
2888 -- Aggregate is statically illegal. Place back in declaration
2890 Set_Expression (N, E);
2891 Set_No_Initialization (N, False);
2893 elsif T = Etype (E) then
2896 elsif Nkind (E) = N_Aggregate
2897 and then Present (Component_Associations (E))
2898 and then Present (Choices (First (Component_Associations (E))))
2899 and then Nkind (First
2900 (Choices (First (Component_Associations (E))))) = N_Others_Choice
2905 Apply_Length_Check (E, T);
2908 -- If the type is limited unconstrained with defaulted discriminants and
2909 -- there is no expression, then the object is constrained by the
2910 -- defaults, so it is worthwhile building the corresponding subtype.
2912 elsif (Is_Limited_Record (T) or else Is_Concurrent_Type (T))
2913 and then not Is_Constrained (T)
2914 and then Has_Discriminants (T)
2917 Act_T := Build_Default_Subtype (T, N);
2919 -- Ada 2005: a limited object may be initialized by means of an
2920 -- aggregate. If the type has default discriminants it has an
2921 -- unconstrained nominal type, Its actual subtype will be obtained
2922 -- from the aggregate, and not from the default discriminants.
2927 Rewrite (Object_Definition (N), New_Occurrence_Of (Act_T, Loc));
2929 elsif Present (Underlying_Type (T))
2930 and then not Is_Constrained (Underlying_Type (T))
2931 and then Has_Discriminants (Underlying_Type (T))
2932 and then Nkind (E) = N_Function_Call
2933 and then Constant_Present (N)
2935 -- The back-end has problems with constants of a discriminated type
2936 -- with defaults, if the initial value is a function call. We
2937 -- generate an intermediate temporary for the result of the call.
2938 -- It is unclear why this should make it acceptable to gcc. ???
2940 Remove_Side_Effects (E);
2943 -- Check No_Wide_Characters restriction
2945 if T = Standard_Wide_Character
2946 or else T = Standard_Wide_Wide_Character
2947 or else Root_Type (T) = Standard_Wide_String
2948 or else Root_Type (T) = Standard_Wide_Wide_String
2950 Check_Restriction (No_Wide_Characters, Object_Definition (N));
2953 -- Indicate this is not set in source. Certainly true for constants,
2954 -- and true for variables so far (will be reset for a variable if and
2955 -- when we encounter a modification in the source).
2957 Set_Never_Set_In_Source (Id, True);
2959 -- Now establish the proper kind and type of the object
2961 if Constant_Present (N) then
2962 Set_Ekind (Id, E_Constant);
2963 Set_Is_True_Constant (Id, True);
2966 Set_Ekind (Id, E_Variable);
2968 -- A variable is set as shared passive if it appears in a shared
2969 -- passive package, and is at the outer level. This is not done
2970 -- for entities generated during expansion, because those are
2971 -- always manipulated locally.
2973 if Is_Shared_Passive (Current_Scope)
2974 and then Is_Library_Level_Entity (Id)
2975 and then Comes_From_Source (Id)
2977 Set_Is_Shared_Passive (Id);
2978 Check_Shared_Var (Id, T, N);
2981 -- Set Has_Initial_Value if initializing expression present. Note
2982 -- that if there is no initializing expression, we leave the state
2983 -- of this flag unchanged (usually it will be False, but notably in
2984 -- the case of exception choice variables, it will already be true).
2987 Set_Has_Initial_Value (Id, True);
2991 -- Initialize alignment and size and capture alignment setting
2993 Init_Alignment (Id);
2995 Set_Optimize_Alignment_Flags (Id);
2997 -- Deal with aliased case
2999 if Aliased_Present (N) then
3000 Set_Is_Aliased (Id);
3002 -- If the object is aliased and the type is unconstrained with
3003 -- defaulted discriminants and there is no expression, then the
3004 -- object is constrained by the defaults, so it is worthwhile
3005 -- building the corresponding subtype.
3007 -- Ada 2005 (AI-363): If the aliased object is discriminated and
3008 -- unconstrained, then only establish an actual subtype if the
3009 -- nominal subtype is indefinite. In definite cases the object is
3010 -- unconstrained in Ada 2005.
3013 and then Is_Record_Type (T)
3014 and then not Is_Constrained (T)
3015 and then Has_Discriminants (T)
3016 and then (Ada_Version < Ada_05 or else Is_Indefinite_Subtype (T))
3018 Set_Actual_Subtype (Id, Build_Default_Subtype (T, N));
3022 -- Now we can set the type of the object
3024 Set_Etype (Id, Act_T);
3026 -- Deal with controlled types
3028 if Has_Controlled_Component (Etype (Id))
3029 or else Is_Controlled (Etype (Id))
3031 if not Is_Library_Level_Entity (Id) then
3032 Check_Restriction (No_Nested_Finalization, N);
3034 Validate_Controlled_Object (Id);
3037 -- Generate a warning when an initialization causes an obvious ABE
3038 -- violation. If the init expression is a simple aggregate there
3039 -- shouldn't be any initialize/adjust call generated. This will be
3040 -- true as soon as aggregates are built in place when possible.
3042 -- ??? at the moment we do not generate warnings for temporaries
3043 -- created for those aggregates although Program_Error might be
3044 -- generated if compiled with -gnato.
3046 if Is_Controlled (Etype (Id))
3047 and then Comes_From_Source (Id)
3050 BT : constant Entity_Id := Base_Type (Etype (Id));
3052 Implicit_Call : Entity_Id;
3053 pragma Warnings (Off, Implicit_Call);
3054 -- ??? what is this for (never referenced!)
3056 function Is_Aggr (N : Node_Id) return Boolean;
3057 -- Check that N is an aggregate
3063 function Is_Aggr (N : Node_Id) return Boolean is
3065 case Nkind (Original_Node (N)) is
3066 when N_Aggregate | N_Extension_Aggregate =>
3069 when N_Qualified_Expression |
3071 N_Unchecked_Type_Conversion =>
3072 return Is_Aggr (Expression (Original_Node (N)));
3080 -- If no underlying type, we already are in an error situation.
3081 -- Do not try to add a warning since we do not have access to
3084 if No (Underlying_Type (BT)) then
3085 Implicit_Call := Empty;
3087 -- A generic type does not have usable primitive operators.
3088 -- Initialization calls are built for instances.
3090 elsif Is_Generic_Type (BT) then
3091 Implicit_Call := Empty;
3093 -- If the init expression is not an aggregate, an adjust call
3094 -- will be generated
3096 elsif Present (E) and then not Is_Aggr (E) then
3097 Implicit_Call := Find_Prim_Op (BT, Name_Adjust);
3099 -- If no init expression and we are not in the deferred
3100 -- constant case, an Initialize call will be generated
3102 elsif No (E) and then not Constant_Present (N) then
3103 Implicit_Call := Find_Prim_Op (BT, Name_Initialize);
3106 Implicit_Call := Empty;
3112 if Has_Task (Etype (Id)) then
3113 Check_Restriction (No_Tasking, N);
3115 -- Deal with counting max tasks
3117 -- Nothing to do if inside a generic
3119 if Inside_A_Generic then
3122 -- If library level entity, then count tasks
3124 elsif Is_Library_Level_Entity (Id) then
3125 Check_Restriction (Max_Tasks, N, Count_Tasks (Etype (Id)));
3127 -- If not library level entity, then indicate we don't know max
3128 -- tasks and also check task hierarchy restriction and blocking
3129 -- operation (since starting a task is definitely blocking!)
3132 Check_Restriction (Max_Tasks, N);
3133 Check_Restriction (No_Task_Hierarchy, N);
3134 Check_Potentially_Blocking_Operation (N);
3137 -- A rather specialized test. If we see two tasks being declared
3138 -- of the same type in the same object declaration, and the task
3139 -- has an entry with an address clause, we know that program error
3140 -- will be raised at run-time since we can't have two tasks with
3141 -- entries at the same address.
3143 if Is_Task_Type (Etype (Id)) and then More_Ids (N) then
3148 E := First_Entity (Etype (Id));
3149 while Present (E) loop
3150 if Ekind (E) = E_Entry
3151 and then Present (Get_Attribute_Definition_Clause
3152 (E, Attribute_Address))
3155 ("?more than one task with same entry address", N);
3157 ("\?Program_Error will be raised at run time", N);
3159 Make_Raise_Program_Error (Loc,
3160 Reason => PE_Duplicated_Entry_Address));
3170 -- Some simple constant-propagation: if the expression is a constant
3171 -- string initialized with a literal, share the literal. This avoids
3175 and then Is_Entity_Name (E)
3176 and then Ekind (Entity (E)) = E_Constant
3177 and then Base_Type (Etype (E)) = Standard_String
3180 Val : constant Node_Id := Constant_Value (Entity (E));
3183 and then Nkind (Val) = N_String_Literal
3185 Rewrite (E, New_Copy (Val));
3190 -- Another optimization: if the nominal subtype is unconstrained and
3191 -- the expression is a function call that returns an unconstrained
3192 -- type, rewrite the declaration as a renaming of the result of the
3193 -- call. The exceptions below are cases where the copy is expected,
3194 -- either by the back end (Aliased case) or by the semantics, as for
3195 -- initializing controlled types or copying tags for classwide types.
3198 and then Nkind (E) = N_Explicit_Dereference
3199 and then Nkind (Original_Node (E)) = N_Function_Call
3200 and then not Is_Library_Level_Entity (Id)
3201 and then not Is_Constrained (Underlying_Type (T))
3202 and then not Is_Aliased (Id)
3203 and then not Is_Class_Wide_Type (T)
3204 and then not Is_Controlled (T)
3205 and then not Has_Controlled_Component (Base_Type (T))
3206 and then Expander_Active
3209 Make_Object_Renaming_Declaration (Loc,
3210 Defining_Identifier => Id,
3211 Access_Definition => Empty,
3212 Subtype_Mark => New_Occurrence_Of
3213 (Base_Type (Etype (Id)), Loc),
3216 Set_Renamed_Object (Id, E);
3218 -- Force generation of debugging information for the constant and for
3219 -- the renamed function call.
3221 Set_Debug_Info_Needed (Id);
3222 Set_Debug_Info_Needed (Entity (Prefix (E)));
3225 if Present (Prev_Entity)
3226 and then Is_Frozen (Prev_Entity)
3227 and then not Error_Posted (Id)
3229 Error_Msg_N ("full constant declaration appears too late", N);
3232 Check_Eliminated (Id);
3234 -- Deal with setting In_Private_Part flag if in private part
3236 if Ekind (Scope (Id)) = E_Package
3237 and then In_Private_Part (Scope (Id))
3239 Set_In_Private_Part (Id);
3242 -- Check for violation of No_Local_Timing_Events
3244 if Is_RTE (Etype (Id), RE_Timing_Event)
3245 and then not Is_Library_Level_Entity (Id)
3247 Check_Restriction (No_Local_Timing_Events, N);
3249 end Analyze_Object_Declaration;
3251 ---------------------------
3252 -- Analyze_Others_Choice --
3253 ---------------------------
3255 -- Nothing to do for the others choice node itself, the semantic analysis
3256 -- of the others choice will occur as part of the processing of the parent
3258 procedure Analyze_Others_Choice (N : Node_Id) is
3259 pragma Warnings (Off, N);
3262 end Analyze_Others_Choice;
3264 -------------------------------------------
3265 -- Analyze_Private_Extension_Declaration --
3266 -------------------------------------------
3268 procedure Analyze_Private_Extension_Declaration (N : Node_Id) is
3269 T : constant Entity_Id := Defining_Identifier (N);
3270 Indic : constant Node_Id := Subtype_Indication (N);
3271 Parent_Type : Entity_Id;
3272 Parent_Base : Entity_Id;
3275 -- Ada 2005 (AI-251): Decorate all names in list of ancestor interfaces
3277 if Is_Non_Empty_List (Interface_List (N)) then
3283 Intf := First (Interface_List (N));
3284 while Present (Intf) loop
3285 T := Find_Type_Of_Subtype_Indic (Intf);
3287 Diagnose_Interface (Intf, T);
3293 Generate_Definition (T);
3296 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
3297 Parent_Base := Base_Type (Parent_Type);
3299 if Parent_Type = Any_Type
3300 or else Etype (Parent_Type) = Any_Type
3302 Set_Ekind (T, Ekind (Parent_Type));
3303 Set_Etype (T, Any_Type);
3306 elsif not Is_Tagged_Type (Parent_Type) then
3308 ("parent of type extension must be a tagged type ", Indic);
3311 elsif Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
3312 Error_Msg_N ("premature derivation of incomplete type", Indic);
3315 elsif Is_Concurrent_Type (Parent_Type) then
3317 ("parent type of a private extension cannot be "
3318 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
3320 Set_Etype (T, Any_Type);
3321 Set_Ekind (T, E_Limited_Private_Type);
3322 Set_Private_Dependents (T, New_Elmt_List);
3323 Set_Error_Posted (T);
3327 -- Perhaps the parent type should be changed to the class-wide type's
3328 -- specific type in this case to prevent cascading errors ???
3330 if Is_Class_Wide_Type (Parent_Type) then
3332 ("parent of type extension must not be a class-wide type", Indic);
3336 if (not Is_Package_Or_Generic_Package (Current_Scope)
3337 and then Nkind (Parent (N)) /= N_Generic_Subprogram_Declaration)
3338 or else In_Private_Part (Current_Scope)
3341 Error_Msg_N ("invalid context for private extension", N);
3344 -- Set common attributes
3346 Set_Is_Pure (T, Is_Pure (Current_Scope));
3347 Set_Scope (T, Current_Scope);
3348 Set_Ekind (T, E_Record_Type_With_Private);
3349 Init_Size_Align (T);
3351 Set_Etype (T, Parent_Base);
3352 Set_Has_Task (T, Has_Task (Parent_Base));
3354 Set_Convention (T, Convention (Parent_Type));
3355 Set_First_Rep_Item (T, First_Rep_Item (Parent_Type));
3356 Set_Is_First_Subtype (T);
3357 Make_Class_Wide_Type (T);
3359 if Unknown_Discriminants_Present (N) then
3360 Set_Discriminant_Constraint (T, No_Elist);
3363 Build_Derived_Record_Type (N, Parent_Type, T);
3365 -- Ada 2005 (AI-443): Synchronized private extension or a rewritten
3366 -- synchronized formal derived type.
3368 if Ada_Version >= Ada_05
3369 and then Synchronized_Present (N)
3371 Set_Is_Limited_Record (T);
3373 -- Formal derived type case
3375 if Is_Generic_Type (T) then
3377 -- The parent must be a tagged limited type or a synchronized
3380 if (not Is_Tagged_Type (Parent_Type)
3381 or else not Is_Limited_Type (Parent_Type))
3383 (not Is_Interface (Parent_Type)
3384 or else not Is_Synchronized_Interface (Parent_Type))
3386 Error_Msg_NE ("parent type of & must be tagged limited " &
3387 "or synchronized", N, T);
3390 -- The progenitors (if any) must be limited or synchronized
3393 if Present (Interfaces (T)) then
3396 Iface_Elmt : Elmt_Id;
3399 Iface_Elmt := First_Elmt (Interfaces (T));
3400 while Present (Iface_Elmt) loop
3401 Iface := Node (Iface_Elmt);
3403 if not Is_Limited_Interface (Iface)
3404 and then not Is_Synchronized_Interface (Iface)
3406 Error_Msg_NE ("progenitor & must be limited " &
3407 "or synchronized", N, Iface);
3410 Next_Elmt (Iface_Elmt);
3415 -- Regular derived extension, the parent must be a limited or
3416 -- synchronized interface.
3419 if not Is_Interface (Parent_Type)
3420 or else (not Is_Limited_Interface (Parent_Type)
3422 not Is_Synchronized_Interface (Parent_Type))
3425 ("parent type of & must be limited interface", N, T);
3429 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
3430 -- extension with a synchronized parent must be explicitly declared
3431 -- synchronized, because the full view will be a synchronized type.
3432 -- This must be checked before the check for limited types below,
3433 -- to ensure that types declared limited are not allowed to extend
3434 -- synchronized interfaces.
3436 elsif Is_Interface (Parent_Type)
3437 and then Is_Synchronized_Interface (Parent_Type)
3438 and then not Synchronized_Present (N)
3441 ("private extension of& must be explicitly synchronized",
3444 elsif Limited_Present (N) then
3445 Set_Is_Limited_Record (T);
3447 if not Is_Limited_Type (Parent_Type)
3449 (not Is_Interface (Parent_Type)
3450 or else not Is_Limited_Interface (Parent_Type))
3452 Error_Msg_NE ("parent type& of limited extension must be limited",
3456 end Analyze_Private_Extension_Declaration;
3458 ---------------------------------
3459 -- Analyze_Subtype_Declaration --
3460 ---------------------------------
3462 procedure Analyze_Subtype_Declaration
3464 Skip : Boolean := False)
3466 Id : constant Entity_Id := Defining_Identifier (N);
3468 R_Checks : Check_Result;
3471 Generate_Definition (Id);
3472 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3473 Init_Size_Align (Id);
3475 -- The following guard condition on Enter_Name is to handle cases where
3476 -- the defining identifier has already been entered into the scope but
3477 -- the declaration as a whole needs to be analyzed.
3479 -- This case in particular happens for derived enumeration types. The
3480 -- derived enumeration type is processed as an inserted enumeration type
3481 -- declaration followed by a rewritten subtype declaration. The defining
3482 -- identifier, however, is entered into the name scope very early in the
3483 -- processing of the original type declaration and therefore needs to be
3484 -- avoided here, when the created subtype declaration is analyzed. (See
3485 -- Build_Derived_Types)
3487 -- This also happens when the full view of a private type is derived
3488 -- type with constraints. In this case the entity has been introduced
3489 -- in the private declaration.
3492 or else (Present (Etype (Id))
3493 and then (Is_Private_Type (Etype (Id))
3494 or else Is_Task_Type (Etype (Id))
3495 or else Is_Rewrite_Substitution (N)))
3503 T := Process_Subtype (Subtype_Indication (N), N, Id, 'P');
3505 -- Inherit common attributes
3507 Set_Is_Generic_Type (Id, Is_Generic_Type (Base_Type (T)));
3508 Set_Is_Volatile (Id, Is_Volatile (T));
3509 Set_Treat_As_Volatile (Id, Treat_As_Volatile (T));
3510 Set_Is_Atomic (Id, Is_Atomic (T));
3511 Set_Is_Ada_2005_Only (Id, Is_Ada_2005_Only (T));
3512 Set_Convention (Id, Convention (T));
3514 -- In the case where there is no constraint given in the subtype
3515 -- indication, Process_Subtype just returns the Subtype_Mark, so its
3516 -- semantic attributes must be established here.
3518 if Nkind (Subtype_Indication (N)) /= N_Subtype_Indication then
3519 Set_Etype (Id, Base_Type (T));
3523 Set_Ekind (Id, E_Array_Subtype);
3524 Copy_Array_Subtype_Attributes (Id, T);
3526 when Decimal_Fixed_Point_Kind =>
3527 Set_Ekind (Id, E_Decimal_Fixed_Point_Subtype);
3528 Set_Digits_Value (Id, Digits_Value (T));
3529 Set_Delta_Value (Id, Delta_Value (T));
3530 Set_Scale_Value (Id, Scale_Value (T));
3531 Set_Small_Value (Id, Small_Value (T));
3532 Set_Scalar_Range (Id, Scalar_Range (T));
3533 Set_Machine_Radix_10 (Id, Machine_Radix_10 (T));
3534 Set_Is_Constrained (Id, Is_Constrained (T));
3535 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
3536 Set_RM_Size (Id, RM_Size (T));
3538 when Enumeration_Kind =>
3539 Set_Ekind (Id, E_Enumeration_Subtype);
3540 Set_First_Literal (Id, First_Literal (Base_Type (T)));
3541 Set_Scalar_Range (Id, Scalar_Range (T));
3542 Set_Is_Character_Type (Id, Is_Character_Type (T));
3543 Set_Is_Constrained (Id, Is_Constrained (T));
3544 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
3545 Set_RM_Size (Id, RM_Size (T));
3547 when Ordinary_Fixed_Point_Kind =>
3548 Set_Ekind (Id, E_Ordinary_Fixed_Point_Subtype);
3549 Set_Scalar_Range (Id, Scalar_Range (T));
3550 Set_Small_Value (Id, Small_Value (T));
3551 Set_Delta_Value (Id, Delta_Value (T));
3552 Set_Is_Constrained (Id, Is_Constrained (T));
3553 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
3554 Set_RM_Size (Id, RM_Size (T));
3557 Set_Ekind (Id, E_Floating_Point_Subtype);
3558 Set_Scalar_Range (Id, Scalar_Range (T));
3559 Set_Digits_Value (Id, Digits_Value (T));
3560 Set_Is_Constrained (Id, Is_Constrained (T));
3562 when Signed_Integer_Kind =>
3563 Set_Ekind (Id, E_Signed_Integer_Subtype);
3564 Set_Scalar_Range (Id, Scalar_Range (T));
3565 Set_Is_Constrained (Id, Is_Constrained (T));
3566 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
3567 Set_RM_Size (Id, RM_Size (T));
3569 when Modular_Integer_Kind =>
3570 Set_Ekind (Id, E_Modular_Integer_Subtype);
3571 Set_Scalar_Range (Id, Scalar_Range (T));
3572 Set_Is_Constrained (Id, Is_Constrained (T));
3573 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
3574 Set_RM_Size (Id, RM_Size (T));
3576 when Class_Wide_Kind =>
3577 Set_Ekind (Id, E_Class_Wide_Subtype);
3578 Set_First_Entity (Id, First_Entity (T));
3579 Set_Last_Entity (Id, Last_Entity (T));
3580 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
3581 Set_Cloned_Subtype (Id, T);
3582 Set_Is_Tagged_Type (Id, True);
3583 Set_Has_Unknown_Discriminants
3586 if Ekind (T) = E_Class_Wide_Subtype then
3587 Set_Equivalent_Type (Id, Equivalent_Type (T));
3590 when E_Record_Type | E_Record_Subtype =>
3591 Set_Ekind (Id, E_Record_Subtype);
3593 if Ekind (T) = E_Record_Subtype
3594 and then Present (Cloned_Subtype (T))
3596 Set_Cloned_Subtype (Id, Cloned_Subtype (T));
3598 Set_Cloned_Subtype (Id, T);
3601 Set_First_Entity (Id, First_Entity (T));
3602 Set_Last_Entity (Id, Last_Entity (T));
3603 Set_Has_Discriminants (Id, Has_Discriminants (T));
3604 Set_Is_Constrained (Id, Is_Constrained (T));
3605 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
3606 Set_Has_Unknown_Discriminants
3607 (Id, Has_Unknown_Discriminants (T));
3609 if Has_Discriminants (T) then
3610 Set_Discriminant_Constraint
3611 (Id, Discriminant_Constraint (T));
3612 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
3614 elsif Has_Unknown_Discriminants (Id) then
3615 Set_Discriminant_Constraint (Id, No_Elist);
3618 if Is_Tagged_Type (T) then
3619 Set_Is_Tagged_Type (Id);
3620 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
3621 Set_Primitive_Operations
3622 (Id, Primitive_Operations (T));
3623 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
3625 if Is_Interface (T) then
3626 Set_Is_Interface (Id);
3627 Set_Is_Limited_Interface (Id, Is_Limited_Interface (T));
3631 when Private_Kind =>
3632 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
3633 Set_Has_Discriminants (Id, Has_Discriminants (T));
3634 Set_Is_Constrained (Id, Is_Constrained (T));
3635 Set_First_Entity (Id, First_Entity (T));
3636 Set_Last_Entity (Id, Last_Entity (T));
3637 Set_Private_Dependents (Id, New_Elmt_List);
3638 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
3639 Set_Has_Unknown_Discriminants
3640 (Id, Has_Unknown_Discriminants (T));
3641 Set_Known_To_Have_Preelab_Init
3642 (Id, Known_To_Have_Preelab_Init (T));
3644 if Is_Tagged_Type (T) then
3645 Set_Is_Tagged_Type (Id);
3646 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
3647 Set_Primitive_Operations (Id, Primitive_Operations (T));
3648 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
3651 -- In general the attributes of the subtype of a private type
3652 -- are the attributes of the partial view of parent. However,
3653 -- the full view may be a discriminated type, and the subtype
3654 -- must share the discriminant constraint to generate correct
3655 -- calls to initialization procedures.
3657 if Has_Discriminants (T) then
3658 Set_Discriminant_Constraint
3659 (Id, Discriminant_Constraint (T));
3660 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
3662 elsif Present (Full_View (T))
3663 and then Has_Discriminants (Full_View (T))
3665 Set_Discriminant_Constraint
3666 (Id, Discriminant_Constraint (Full_View (T)));
3667 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
3669 -- This would seem semantically correct, but apparently
3670 -- confuses the back-end. To be explained and checked with
3671 -- current version ???
3673 -- Set_Has_Discriminants (Id);
3676 Prepare_Private_Subtype_Completion (Id, N);
3679 Set_Ekind (Id, E_Access_Subtype);
3680 Set_Is_Constrained (Id, Is_Constrained (T));
3681 Set_Is_Access_Constant
3682 (Id, Is_Access_Constant (T));
3683 Set_Directly_Designated_Type
3684 (Id, Designated_Type (T));
3685 Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T));
3687 -- A Pure library_item must not contain the declaration of a
3688 -- named access type, except within a subprogram, generic
3689 -- subprogram, task unit, or protected unit, or if it has
3690 -- a specified Storage_Size of zero (RM05-10.2.1(15.4-15.5)).
3692 if Comes_From_Source (Id)
3693 and then In_Pure_Unit
3694 and then not In_Subprogram_Task_Protected_Unit
3695 and then not No_Pool_Assigned (Id)
3698 ("named access types not allowed in pure unit", N);
3701 when Concurrent_Kind =>
3702 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
3703 Set_Corresponding_Record_Type (Id,
3704 Corresponding_Record_Type (T));
3705 Set_First_Entity (Id, First_Entity (T));
3706 Set_First_Private_Entity (Id, First_Private_Entity (T));
3707 Set_Has_Discriminants (Id, Has_Discriminants (T));
3708 Set_Is_Constrained (Id, Is_Constrained (T));
3709 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
3710 Set_Last_Entity (Id, Last_Entity (T));
3712 if Has_Discriminants (T) then
3713 Set_Discriminant_Constraint (Id,
3714 Discriminant_Constraint (T));
3715 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
3718 when E_Incomplete_Type =>
3719 if Ada_Version >= Ada_05 then
3720 Set_Ekind (Id, E_Incomplete_Subtype);
3722 -- Ada 2005 (AI-412): Decorate an incomplete subtype
3723 -- of an incomplete type visible through a limited
3726 if From_With_Type (T)
3727 and then Present (Non_Limited_View (T))
3729 Set_From_With_Type (Id);
3730 Set_Non_Limited_View (Id, Non_Limited_View (T));
3732 -- Ada 2005 (AI-412): Add the regular incomplete subtype
3733 -- to the private dependents of the original incomplete
3734 -- type for future transformation.
3737 Append_Elmt (Id, Private_Dependents (T));
3740 -- If the subtype name denotes an incomplete type an error
3741 -- was already reported by Process_Subtype.
3744 Set_Etype (Id, Any_Type);
3748 raise Program_Error;
3752 if Etype (Id) = Any_Type then
3756 -- Some common processing on all types
3758 Set_Size_Info (Id, T);
3759 Set_First_Rep_Item (Id, First_Rep_Item (T));
3763 Set_Is_Immediately_Visible (Id, True);
3764 Set_Depends_On_Private (Id, Has_Private_Component (T));
3765 Set_Is_Descendent_Of_Address (Id, Is_Descendent_Of_Address (T));
3767 if Is_Interface (T) then
3768 Set_Is_Interface (Id);
3771 if Present (Generic_Parent_Type (N))
3774 (Parent (Generic_Parent_Type (N))) /= N_Formal_Type_Declaration
3776 (Formal_Type_Definition (Parent (Generic_Parent_Type (N))))
3777 /= N_Formal_Private_Type_Definition)
3779 if Is_Tagged_Type (Id) then
3781 -- If this is a generic actual subtype for a synchronized type,
3782 -- the primitive operations are those of the corresponding record
3783 -- for which there is a separate subtype declaration.
3785 if Is_Concurrent_Type (Id) then
3787 elsif Is_Class_Wide_Type (Id) then
3788 Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T));
3790 Derive_Subprograms (Generic_Parent_Type (N), Id, T);
3793 elsif Scope (Etype (Id)) /= Standard_Standard then
3794 Derive_Subprograms (Generic_Parent_Type (N), Id);
3798 if Is_Private_Type (T)
3799 and then Present (Full_View (T))
3801 Conditional_Delay (Id, Full_View (T));
3803 -- The subtypes of components or subcomponents of protected types
3804 -- do not need freeze nodes, which would otherwise appear in the
3805 -- wrong scope (before the freeze node for the protected type). The
3806 -- proper subtypes are those of the subcomponents of the corresponding
3809 elsif Ekind (Scope (Id)) /= E_Protected_Type
3810 and then Present (Scope (Scope (Id))) -- error defense!
3811 and then Ekind (Scope (Scope (Id))) /= E_Protected_Type
3813 Conditional_Delay (Id, T);
3816 -- Check that constraint_error is raised for a scalar subtype
3817 -- indication when the lower or upper bound of a non-null range
3818 -- lies outside the range of the type mark.
3820 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
3821 if Is_Scalar_Type (Etype (Id))
3822 and then Scalar_Range (Id) /=
3823 Scalar_Range (Etype (Subtype_Mark
3824 (Subtype_Indication (N))))
3828 Etype (Subtype_Mark (Subtype_Indication (N))));
3830 elsif Is_Array_Type (Etype (Id))
3831 and then Present (First_Index (Id))
3833 -- This really should be a subprogram that finds the indications
3836 if ((Nkind (First_Index (Id)) = N_Identifier
3837 and then Ekind (Entity (First_Index (Id))) in Scalar_Kind)
3838 or else Nkind (First_Index (Id)) = N_Subtype_Indication)
3840 Nkind (Scalar_Range (Etype (First_Index (Id)))) = N_Range
3843 Target_Typ : constant Entity_Id :=
3846 (Subtype_Mark (Subtype_Indication (N)))));
3850 (Scalar_Range (Etype (First_Index (Id))),
3852 Etype (First_Index (Id)),
3853 Defining_Identifier (N));
3859 Sloc (Defining_Identifier (N)));
3865 Set_Optimize_Alignment_Flags (Id);
3866 Check_Eliminated (Id);
3867 end Analyze_Subtype_Declaration;
3869 --------------------------------
3870 -- Analyze_Subtype_Indication --
3871 --------------------------------
3873 procedure Analyze_Subtype_Indication (N : Node_Id) is
3874 T : constant Entity_Id := Subtype_Mark (N);
3875 R : constant Node_Id := Range_Expression (Constraint (N));
3882 Set_Etype (N, Etype (R));
3883 Resolve (R, Entity (T));
3885 Set_Error_Posted (R);
3886 Set_Error_Posted (T);
3888 end Analyze_Subtype_Indication;
3890 ------------------------------
3891 -- Analyze_Type_Declaration --
3892 ------------------------------
3894 procedure Analyze_Type_Declaration (N : Node_Id) is
3895 Def : constant Node_Id := Type_Definition (N);
3896 Def_Id : constant Entity_Id := Defining_Identifier (N);
3900 Is_Remote : constant Boolean :=
3901 (Is_Remote_Types (Current_Scope)
3902 or else Is_Remote_Call_Interface (Current_Scope))
3903 and then not (In_Private_Part (Current_Scope)
3904 or else In_Package_Body (Current_Scope));
3906 procedure Check_Ops_From_Incomplete_Type;
3907 -- If there is a tagged incomplete partial view of the type, transfer
3908 -- its operations to the full view, and indicate that the type of the
3909 -- controlling parameter (s) is this full view.
3911 ------------------------------------
3912 -- Check_Ops_From_Incomplete_Type --
3913 ------------------------------------
3915 procedure Check_Ops_From_Incomplete_Type is
3922 and then Ekind (Prev) = E_Incomplete_Type
3923 and then Is_Tagged_Type (Prev)
3924 and then Is_Tagged_Type (T)
3926 Elmt := First_Elmt (Primitive_Operations (Prev));
3927 while Present (Elmt) loop
3929 Prepend_Elmt (Op, Primitive_Operations (T));
3931 Formal := First_Formal (Op);
3932 while Present (Formal) loop
3933 if Etype (Formal) = Prev then
3934 Set_Etype (Formal, T);
3937 Next_Formal (Formal);
3940 if Etype (Op) = Prev then
3947 end Check_Ops_From_Incomplete_Type;
3949 -- Start of processing for Analyze_Type_Declaration
3952 Prev := Find_Type_Name (N);
3954 -- The full view, if present, now points to the current type
3956 -- Ada 2005 (AI-50217): If the type was previously decorated when
3957 -- imported through a LIMITED WITH clause, it appears as incomplete
3958 -- but has no full view.
3959 -- If the incomplete view is tagged, a class_wide type has been
3960 -- created already. Use it for the full view as well, to prevent
3961 -- multiple incompatible class-wide types that may be created for
3962 -- self-referential anonymous access components.
3964 if Ekind (Prev) = E_Incomplete_Type
3965 and then Present (Full_View (Prev))
3967 T := Full_View (Prev);
3969 if Is_Tagged_Type (Prev)
3970 and then Present (Class_Wide_Type (Prev))
3972 Set_Ekind (T, Ekind (Prev)); -- will be reset later
3973 Set_Class_Wide_Type (T, Class_Wide_Type (Prev));
3974 Set_Etype (Class_Wide_Type (T), T);
3981 Set_Is_Pure (T, Is_Pure (Current_Scope));
3983 -- We set the flag Is_First_Subtype here. It is needed to set the
3984 -- corresponding flag for the Implicit class-wide-type created
3985 -- during tagged types processing.
3987 Set_Is_First_Subtype (T, True);
3989 -- Only composite types other than array types are allowed to have
3994 -- For derived types, the rule will be checked once we've figured
3995 -- out the parent type.
3997 when N_Derived_Type_Definition =>
4000 -- For record types, discriminants are allowed
4002 when N_Record_Definition =>
4006 if Present (Discriminant_Specifications (N)) then
4008 ("elementary or array type cannot have discriminants",
4010 (First (Discriminant_Specifications (N))));
4014 -- Elaborate the type definition according to kind, and generate
4015 -- subsidiary (implicit) subtypes where needed. We skip this if it was
4016 -- already done (this happens during the reanalysis that follows a call
4017 -- to the high level optimizer).
4019 if not Analyzed (T) then
4024 when N_Access_To_Subprogram_Definition =>
4025 Access_Subprogram_Declaration (T, Def);
4027 -- If this is a remote access to subprogram, we must create the
4028 -- equivalent fat pointer type, and related subprograms.
4031 Process_Remote_AST_Declaration (N);
4034 -- Validate categorization rule against access type declaration
4035 -- usually a violation in Pure unit, Shared_Passive unit.
4037 Validate_Access_Type_Declaration (T, N);
4039 when N_Access_To_Object_Definition =>
4040 Access_Type_Declaration (T, Def);
4042 -- Validate categorization rule against access type declaration
4043 -- usually a violation in Pure unit, Shared_Passive unit.
4045 Validate_Access_Type_Declaration (T, N);
4047 -- If we are in a Remote_Call_Interface package and define a
4048 -- RACW, then calling stubs and specific stream attributes
4052 and then Is_Remote_Access_To_Class_Wide_Type (Def_Id)
4054 Add_RACW_Features (Def_Id);
4057 -- Set no strict aliasing flag if config pragma seen
4059 if Opt.No_Strict_Aliasing then
4060 Set_No_Strict_Aliasing (Base_Type (Def_Id));
4063 when N_Array_Type_Definition =>
4064 Array_Type_Declaration (T, Def);
4066 when N_Derived_Type_Definition =>
4067 Derived_Type_Declaration (T, N, T /= Def_Id);
4069 when N_Enumeration_Type_Definition =>
4070 Enumeration_Type_Declaration (T, Def);
4072 when N_Floating_Point_Definition =>
4073 Floating_Point_Type_Declaration (T, Def);
4075 when N_Decimal_Fixed_Point_Definition =>
4076 Decimal_Fixed_Point_Type_Declaration (T, Def);
4078 when N_Ordinary_Fixed_Point_Definition =>
4079 Ordinary_Fixed_Point_Type_Declaration (T, Def);
4081 when N_Signed_Integer_Type_Definition =>
4082 Signed_Integer_Type_Declaration (T, Def);
4084 when N_Modular_Type_Definition =>
4085 Modular_Type_Declaration (T, Def);
4087 when N_Record_Definition =>
4088 Record_Type_Declaration (T, N, Prev);
4091 raise Program_Error;
4096 if Etype (T) = Any_Type then
4100 -- Some common processing for all types
4102 Set_Depends_On_Private (T, Has_Private_Component (T));
4103 Check_Ops_From_Incomplete_Type;
4105 -- Both the declared entity, and its anonymous base type if one
4106 -- was created, need freeze nodes allocated.
4109 B : constant Entity_Id := Base_Type (T);
4112 -- In the case where the base type differs from the first subtype, we
4113 -- pre-allocate a freeze node, and set the proper link to the first
4114 -- subtype. Freeze_Entity will use this preallocated freeze node when
4115 -- it freezes the entity.
4117 -- This does not apply if the base type is a generic type, whose
4118 -- declaration is independent of the current derived definition.
4120 if B /= T and then not Is_Generic_Type (B) then
4121 Ensure_Freeze_Node (B);
4122 Set_First_Subtype_Link (Freeze_Node (B), T);
4125 -- A type that is imported through a limited_with clause cannot
4126 -- generate any code, and thus need not be frozen. However, an access
4127 -- type with an imported designated type needs a finalization list,
4128 -- which may be referenced in some other package that has non-limited
4129 -- visibility on the designated type. Thus we must create the
4130 -- finalization list at the point the access type is frozen, to
4131 -- prevent unsatisfied references at link time.
4133 if not From_With_Type (T) or else Is_Access_Type (T) then
4134 Set_Has_Delayed_Freeze (T);
4138 -- Case where T is the full declaration of some private type which has
4139 -- been swapped in Defining_Identifier (N).
4141 if T /= Def_Id and then Is_Private_Type (Def_Id) then
4142 Process_Full_View (N, T, Def_Id);
4144 -- Record the reference. The form of this is a little strange, since
4145 -- the full declaration has been swapped in. So the first parameter
4146 -- here represents the entity to which a reference is made which is
4147 -- the "real" entity, i.e. the one swapped in, and the second
4148 -- parameter provides the reference location.
4150 -- Also, we want to kill Has_Pragma_Unreferenced temporarily here
4151 -- since we don't want a complaint about the full type being an
4152 -- unwanted reference to the private type
4155 B : constant Boolean := Has_Pragma_Unreferenced (T);
4157 Set_Has_Pragma_Unreferenced (T, False);
4158 Generate_Reference (T, T, 'c');
4159 Set_Has_Pragma_Unreferenced (T, B);
4162 Set_Completion_Referenced (Def_Id);
4164 -- For completion of incomplete type, process incomplete dependents
4165 -- and always mark the full type as referenced (it is the incomplete
4166 -- type that we get for any real reference).
4168 elsif Ekind (Prev) = E_Incomplete_Type then
4169 Process_Incomplete_Dependents (N, T, Prev);
4170 Generate_Reference (Prev, Def_Id, 'c');
4171 Set_Completion_Referenced (Def_Id);
4173 -- If not private type or incomplete type completion, this is a real
4174 -- definition of a new entity, so record it.
4177 Generate_Definition (Def_Id);
4180 if Chars (Scope (Def_Id)) = Name_System
4181 and then Chars (Def_Id) = Name_Address
4182 and then Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (N)))
4184 Set_Is_Descendent_Of_Address (Def_Id);
4185 Set_Is_Descendent_Of_Address (Base_Type (Def_Id));
4186 Set_Is_Descendent_Of_Address (Prev);
4189 Set_Optimize_Alignment_Flags (Def_Id);
4190 Check_Eliminated (Def_Id);
4191 end Analyze_Type_Declaration;
4193 --------------------------
4194 -- Analyze_Variant_Part --
4195 --------------------------
4197 procedure Analyze_Variant_Part (N : Node_Id) is
4199 procedure Non_Static_Choice_Error (Choice : Node_Id);
4200 -- Error routine invoked by the generic instantiation below when the
4201 -- variant part has a non static choice.
4203 procedure Process_Declarations (Variant : Node_Id);
4204 -- Analyzes all the declarations associated with a Variant. Needed by
4205 -- the generic instantiation below.
4207 package Variant_Choices_Processing is new
4208 Generic_Choices_Processing
4209 (Get_Alternatives => Variants,
4210 Get_Choices => Discrete_Choices,
4211 Process_Empty_Choice => No_OP,
4212 Process_Non_Static_Choice => Non_Static_Choice_Error,
4213 Process_Associated_Node => Process_Declarations);
4214 use Variant_Choices_Processing;
4215 -- Instantiation of the generic choice processing package
4217 -----------------------------
4218 -- Non_Static_Choice_Error --
4219 -----------------------------
4221 procedure Non_Static_Choice_Error (Choice : Node_Id) is
4223 Flag_Non_Static_Expr
4224 ("choice given in variant part is not static!", Choice);
4225 end Non_Static_Choice_Error;
4227 --------------------------
4228 -- Process_Declarations --
4229 --------------------------
4231 procedure Process_Declarations (Variant : Node_Id) is
4233 if not Null_Present (Component_List (Variant)) then
4234 Analyze_Declarations (Component_Items (Component_List (Variant)));
4236 if Present (Variant_Part (Component_List (Variant))) then
4237 Analyze (Variant_Part (Component_List (Variant)));
4240 end Process_Declarations;
4244 Discr_Name : Node_Id;
4245 Discr_Type : Entity_Id;
4247 Case_Table : Choice_Table_Type (1 .. Number_Of_Choices (N));
4249 Dont_Care : Boolean;
4250 Others_Present : Boolean := False;
4252 pragma Warnings (Off, Case_Table);
4253 pragma Warnings (Off, Last_Choice);
4254 pragma Warnings (Off, Dont_Care);
4255 pragma Warnings (Off, Others_Present);
4256 -- We don't care about the assigned values of any of these
4258 -- Start of processing for Analyze_Variant_Part
4261 Discr_Name := Name (N);
4262 Analyze (Discr_Name);
4264 -- If Discr_Name bad, get out (prevent cascaded errors)
4266 if Etype (Discr_Name) = Any_Type then
4270 -- Check invalid discriminant in variant part
4272 if Ekind (Entity (Discr_Name)) /= E_Discriminant then
4273 Error_Msg_N ("invalid discriminant name in variant part", Discr_Name);
4276 Discr_Type := Etype (Entity (Discr_Name));
4278 if not Is_Discrete_Type (Discr_Type) then
4280 ("discriminant in a variant part must be of a discrete type",
4285 -- Call the instantiated Analyze_Choices which does the rest of the work
4288 (N, Discr_Type, Case_Table, Last_Choice, Dont_Care, Others_Present);
4289 end Analyze_Variant_Part;
4291 ----------------------------
4292 -- Array_Type_Declaration --
4293 ----------------------------
4295 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is
4296 Component_Def : constant Node_Id := Component_Definition (Def);
4297 Element_Type : Entity_Id;
4298 Implicit_Base : Entity_Id;
4300 Related_Id : Entity_Id := Empty;
4302 P : constant Node_Id := Parent (Def);
4306 if Nkind (Def) = N_Constrained_Array_Definition then
4307 Index := First (Discrete_Subtype_Definitions (Def));
4309 Index := First (Subtype_Marks (Def));
4312 -- Find proper names for the implicit types which may be public. In case
4313 -- of anonymous arrays we use the name of the first object of that type
4317 Related_Id := Defining_Identifier (P);
4323 while Present (Index) loop
4326 -- Add a subtype declaration for each index of private array type
4327 -- declaration whose etype is also private. For example:
4330 -- type Index is private;
4332 -- type Table is array (Index) of ...
4335 -- This is currently required by the expander for the internally
4336 -- generated equality subprogram of records with variant parts in
4337 -- which the etype of some component is such private type.
4339 if Ekind (Current_Scope) = E_Package
4340 and then In_Private_Part (Current_Scope)
4341 and then Has_Private_Declaration (Etype (Index))
4344 Loc : constant Source_Ptr := Sloc (Def);
4349 New_E := Make_Temporary (Loc, 'T');
4350 Set_Is_Internal (New_E);
4353 Make_Subtype_Declaration (Loc,
4354 Defining_Identifier => New_E,
4355 Subtype_Indication =>
4356 New_Occurrence_Of (Etype (Index), Loc));
4358 Insert_Before (Parent (Def), Decl);
4360 Set_Etype (Index, New_E);
4362 -- If the index is a range the Entity attribute is not
4363 -- available. Example:
4366 -- type T is private;
4368 -- type T is new Natural;
4369 -- Table : array (T(1) .. T(10)) of Boolean;
4372 if Nkind (Index) /= N_Range then
4373 Set_Entity (Index, New_E);
4378 Make_Index (Index, P, Related_Id, Nb_Index);
4380 Nb_Index := Nb_Index + 1;
4383 -- Process subtype indication if one is present
4385 if Present (Subtype_Indication (Component_Def)) then
4388 (Subtype_Indication (Component_Def), P, Related_Id, 'C');
4390 -- Ada 2005 (AI-230): Access Definition case
4392 else pragma Assert (Present (Access_Definition (Component_Def)));
4394 -- Indicate that the anonymous access type is created by the
4395 -- array type declaration.
4397 Element_Type := Access_Definition
4399 N => Access_Definition (Component_Def));
4400 Set_Is_Local_Anonymous_Access (Element_Type);
4402 -- Propagate the parent. This field is needed if we have to generate
4403 -- the master_id associated with an anonymous access to task type
4404 -- component (see Expand_N_Full_Type_Declaration.Build_Master)
4406 Set_Parent (Element_Type, Parent (T));
4408 -- Ada 2005 (AI-230): In case of components that are anonymous access
4409 -- types the level of accessibility depends on the enclosing type
4412 Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230)
4414 -- Ada 2005 (AI-254)
4417 CD : constant Node_Id :=
4418 Access_To_Subprogram_Definition
4419 (Access_Definition (Component_Def));
4421 if Present (CD) and then Protected_Present (CD) then
4423 Replace_Anonymous_Access_To_Protected_Subprogram (Def);
4428 -- Constrained array case
4431 T := Create_Itype (E_Void, P, Related_Id, 'T');
4434 if Nkind (Def) = N_Constrained_Array_Definition then
4436 -- Establish Implicit_Base as unconstrained base type
4438 Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B');
4440 Set_Etype (Implicit_Base, Implicit_Base);
4441 Set_Scope (Implicit_Base, Current_Scope);
4442 Set_Has_Delayed_Freeze (Implicit_Base);
4444 -- The constrained array type is a subtype of the unconstrained one
4446 Set_Ekind (T, E_Array_Subtype);
4447 Init_Size_Align (T);
4448 Set_Etype (T, Implicit_Base);
4449 Set_Scope (T, Current_Scope);
4450 Set_Is_Constrained (T, True);
4451 Set_First_Index (T, First (Discrete_Subtype_Definitions (Def)));
4452 Set_Has_Delayed_Freeze (T);
4454 -- Complete setup of implicit base type
4456 Set_First_Index (Implicit_Base, First_Index (T));
4457 Set_Component_Type (Implicit_Base, Element_Type);
4458 Set_Has_Task (Implicit_Base, Has_Task (Element_Type));
4459 Set_Component_Size (Implicit_Base, Uint_0);
4460 Set_Packed_Array_Type (Implicit_Base, Empty);
4461 Set_Has_Controlled_Component
4462 (Implicit_Base, Has_Controlled_Component
4464 or else Is_Controlled
4466 Set_Finalize_Storage_Only
4467 (Implicit_Base, Finalize_Storage_Only
4470 -- Unconstrained array case
4473 Set_Ekind (T, E_Array_Type);
4474 Init_Size_Align (T);
4476 Set_Scope (T, Current_Scope);
4477 Set_Component_Size (T, Uint_0);
4478 Set_Is_Constrained (T, False);
4479 Set_First_Index (T, First (Subtype_Marks (Def)));
4480 Set_Has_Delayed_Freeze (T, True);
4481 Set_Has_Task (T, Has_Task (Element_Type));
4482 Set_Has_Controlled_Component (T, Has_Controlled_Component
4485 Is_Controlled (Element_Type));
4486 Set_Finalize_Storage_Only (T, Finalize_Storage_Only
4490 -- Common attributes for both cases
4492 Set_Component_Type (Base_Type (T), Element_Type);
4493 Set_Packed_Array_Type (T, Empty);
4495 if Aliased_Present (Component_Definition (Def)) then
4496 Set_Has_Aliased_Components (Etype (T));
4499 -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the
4500 -- array type to ensure that objects of this type are initialized.
4502 if Ada_Version >= Ada_05
4503 and then Can_Never_Be_Null (Element_Type)
4505 Set_Can_Never_Be_Null (T);
4507 if Null_Exclusion_Present (Component_Definition (Def))
4509 -- No need to check itypes because in their case this check was
4510 -- done at their point of creation
4512 and then not Is_Itype (Element_Type)
4515 ("`NOT NULL` not allowed (null already excluded)",
4516 Subtype_Indication (Component_Definition (Def)));
4520 Priv := Private_Component (Element_Type);
4522 if Present (Priv) then
4524 -- Check for circular definitions
4526 if Priv = Any_Type then
4527 Set_Component_Type (Etype (T), Any_Type);
4529 -- There is a gap in the visibility of operations on the composite
4530 -- type only if the component type is defined in a different scope.
4532 elsif Scope (Priv) = Current_Scope then
4535 elsif Is_Limited_Type (Priv) then
4536 Set_Is_Limited_Composite (Etype (T));
4537 Set_Is_Limited_Composite (T);
4539 Set_Is_Private_Composite (Etype (T));
4540 Set_Is_Private_Composite (T);
4544 -- A syntax error in the declaration itself may lead to an empty index
4545 -- list, in which case do a minimal patch.
4547 if No (First_Index (T)) then
4548 Error_Msg_N ("missing index definition in array type declaration", T);
4551 Indices : constant List_Id :=
4552 New_List (New_Occurrence_Of (Any_Id, Sloc (T)));
4554 Set_Discrete_Subtype_Definitions (Def, Indices);
4555 Set_First_Index (T, First (Indices));
4560 -- Create a concatenation operator for the new type. Internal array
4561 -- types created for packed entities do not need such, they are
4562 -- compatible with the user-defined type.
4564 if Number_Dimensions (T) = 1
4565 and then not Is_Packed_Array_Type (T)
4567 New_Concatenation_Op (T);
4570 -- In the case of an unconstrained array the parser has already verified
4571 -- that all the indices are unconstrained but we still need to make sure
4572 -- that the element type is constrained.
4574 if Is_Indefinite_Subtype (Element_Type) then
4576 ("unconstrained element type in array declaration",
4577 Subtype_Indication (Component_Def));
4579 elsif Is_Abstract_Type (Element_Type) then
4581 ("the type of a component cannot be abstract",
4582 Subtype_Indication (Component_Def));
4584 end Array_Type_Declaration;
4586 ------------------------------------------------------
4587 -- Replace_Anonymous_Access_To_Protected_Subprogram --
4588 ------------------------------------------------------
4590 function Replace_Anonymous_Access_To_Protected_Subprogram
4591 (N : Node_Id) return Entity_Id
4593 Loc : constant Source_Ptr := Sloc (N);
4595 Curr_Scope : constant Scope_Stack_Entry :=
4596 Scope_Stack.Table (Scope_Stack.Last);
4598 Anon : constant Entity_Id := Make_Temporary (Loc, 'S');
4605 Set_Is_Internal (Anon);
4608 when N_Component_Declaration |
4609 N_Unconstrained_Array_Definition |
4610 N_Constrained_Array_Definition =>
4611 Comp := Component_Definition (N);
4612 Acc := Access_Definition (Comp);
4614 when N_Discriminant_Specification =>
4615 Comp := Discriminant_Type (N);
4618 when N_Parameter_Specification =>
4619 Comp := Parameter_Type (N);
4622 when N_Access_Function_Definition =>
4623 Comp := Result_Definition (N);
4626 when N_Object_Declaration =>
4627 Comp := Object_Definition (N);
4630 when N_Function_Specification =>
4631 Comp := Result_Definition (N);
4635 raise Program_Error;
4638 Decl := Make_Full_Type_Declaration (Loc,
4639 Defining_Identifier => Anon,
4641 Copy_Separate_Tree (Access_To_Subprogram_Definition (Acc)));
4643 Mark_Rewrite_Insertion (Decl);
4645 -- Insert the new declaration in the nearest enclosing scope. If the
4646 -- node is a body and N is its return type, the declaration belongs in
4647 -- the enclosing scope.
4651 if Nkind (P) = N_Subprogram_Body
4652 and then Nkind (N) = N_Function_Specification
4657 while Present (P) and then not Has_Declarations (P) loop
4661 pragma Assert (Present (P));
4663 if Nkind (P) = N_Package_Specification then
4664 Prepend (Decl, Visible_Declarations (P));
4666 Prepend (Decl, Declarations (P));
4669 -- Replace the anonymous type with an occurrence of the new declaration.
4670 -- In all cases the rewritten node does not have the null-exclusion
4671 -- attribute because (if present) it was already inherited by the
4672 -- anonymous entity (Anon). Thus, in case of components we do not
4673 -- inherit this attribute.
4675 if Nkind (N) = N_Parameter_Specification then
4676 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
4677 Set_Etype (Defining_Identifier (N), Anon);
4678 Set_Null_Exclusion_Present (N, False);
4680 elsif Nkind (N) = N_Object_Declaration then
4681 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
4682 Set_Etype (Defining_Identifier (N), Anon);
4684 elsif Nkind (N) = N_Access_Function_Definition then
4685 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
4687 elsif Nkind (N) = N_Function_Specification then
4688 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
4689 Set_Etype (Defining_Unit_Name (N), Anon);
4693 Make_Component_Definition (Loc,
4694 Subtype_Indication => New_Occurrence_Of (Anon, Loc)));
4697 Mark_Rewrite_Insertion (Comp);
4699 if Nkind_In (N, N_Object_Declaration, N_Access_Function_Definition) then
4703 -- Temporarily remove the current scope (record or subprogram) from
4704 -- the stack to add the new declarations to the enclosing scope.
4706 Scope_Stack.Decrement_Last;
4708 Set_Is_Itype (Anon);
4709 Scope_Stack.Append (Curr_Scope);
4712 Set_Ekind (Anon, E_Anonymous_Access_Protected_Subprogram_Type);
4713 Set_Can_Use_Internal_Rep (Anon, not Always_Compatible_Rep_On_Target);
4715 end Replace_Anonymous_Access_To_Protected_Subprogram;
4717 -------------------------------
4718 -- Build_Derived_Access_Type --
4719 -------------------------------
4721 procedure Build_Derived_Access_Type
4723 Parent_Type : Entity_Id;
4724 Derived_Type : Entity_Id)
4726 S : constant Node_Id := Subtype_Indication (Type_Definition (N));
4728 Desig_Type : Entity_Id;
4730 Discr_Con_Elist : Elist_Id;
4731 Discr_Con_El : Elmt_Id;
4735 -- Set the designated type so it is available in case this is an access
4736 -- to a self-referential type, e.g. a standard list type with a next
4737 -- pointer. Will be reset after subtype is built.
4739 Set_Directly_Designated_Type
4740 (Derived_Type, Designated_Type (Parent_Type));
4742 Subt := Process_Subtype (S, N);
4744 if Nkind (S) /= N_Subtype_Indication
4745 and then Subt /= Base_Type (Subt)
4747 Set_Ekind (Derived_Type, E_Access_Subtype);
4750 if Ekind (Derived_Type) = E_Access_Subtype then
4752 Pbase : constant Entity_Id := Base_Type (Parent_Type);
4753 Ibase : constant Entity_Id :=
4754 Create_Itype (Ekind (Pbase), N, Derived_Type, 'B');
4755 Svg_Chars : constant Name_Id := Chars (Ibase);
4756 Svg_Next_E : constant Entity_Id := Next_Entity (Ibase);
4759 Copy_Node (Pbase, Ibase);
4761 Set_Chars (Ibase, Svg_Chars);
4762 Set_Next_Entity (Ibase, Svg_Next_E);
4763 Set_Sloc (Ibase, Sloc (Derived_Type));
4764 Set_Scope (Ibase, Scope (Derived_Type));
4765 Set_Freeze_Node (Ibase, Empty);
4766 Set_Is_Frozen (Ibase, False);
4767 Set_Comes_From_Source (Ibase, False);
4768 Set_Is_First_Subtype (Ibase, False);
4770 Set_Etype (Ibase, Pbase);
4771 Set_Etype (Derived_Type, Ibase);
4775 Set_Directly_Designated_Type
4776 (Derived_Type, Designated_Type (Subt));
4778 Set_Is_Constrained (Derived_Type, Is_Constrained (Subt));
4779 Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type));
4780 Set_Size_Info (Derived_Type, Parent_Type);
4781 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
4782 Set_Depends_On_Private (Derived_Type,
4783 Has_Private_Component (Derived_Type));
4784 Conditional_Delay (Derived_Type, Subt);
4786 -- Ada 2005 (AI-231): Set the null-exclusion attribute, and verify
4787 -- that it is not redundant.
4789 if Null_Exclusion_Present (Type_Definition (N)) then
4790 Set_Can_Never_Be_Null (Derived_Type);
4792 if Can_Never_Be_Null (Parent_Type)
4796 ("`NOT NULL` not allowed (& already excludes null)",
4800 elsif Can_Never_Be_Null (Parent_Type) then
4801 Set_Can_Never_Be_Null (Derived_Type);
4804 -- Note: we do not copy the Storage_Size_Variable, since we always go to
4805 -- the root type for this information.
4807 -- Apply range checks to discriminants for derived record case
4808 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
4810 Desig_Type := Designated_Type (Derived_Type);
4811 if Is_Composite_Type (Desig_Type)
4812 and then (not Is_Array_Type (Desig_Type))
4813 and then Has_Discriminants (Desig_Type)
4814 and then Base_Type (Desig_Type) /= Desig_Type
4816 Discr_Con_Elist := Discriminant_Constraint (Desig_Type);
4817 Discr_Con_El := First_Elmt (Discr_Con_Elist);
4819 Discr := First_Discriminant (Base_Type (Desig_Type));
4820 while Present (Discr_Con_El) loop
4821 Apply_Range_Check (Node (Discr_Con_El), Etype (Discr));
4822 Next_Elmt (Discr_Con_El);
4823 Next_Discriminant (Discr);
4826 end Build_Derived_Access_Type;
4828 ------------------------------
4829 -- Build_Derived_Array_Type --
4830 ------------------------------
4832 procedure Build_Derived_Array_Type
4834 Parent_Type : Entity_Id;
4835 Derived_Type : Entity_Id)
4837 Loc : constant Source_Ptr := Sloc (N);
4838 Tdef : constant Node_Id := Type_Definition (N);
4839 Indic : constant Node_Id := Subtype_Indication (Tdef);
4840 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
4841 Implicit_Base : Entity_Id;
4842 New_Indic : Node_Id;
4844 procedure Make_Implicit_Base;
4845 -- If the parent subtype is constrained, the derived type is a subtype
4846 -- of an implicit base type derived from the parent base.
4848 ------------------------
4849 -- Make_Implicit_Base --
4850 ------------------------
4852 procedure Make_Implicit_Base is
4855 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
4857 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
4858 Set_Etype (Implicit_Base, Parent_Base);
4860 Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base);
4861 Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base);
4863 Set_Has_Delayed_Freeze (Implicit_Base, True);
4864 end Make_Implicit_Base;
4866 -- Start of processing for Build_Derived_Array_Type
4869 if not Is_Constrained (Parent_Type) then
4870 if Nkind (Indic) /= N_Subtype_Indication then
4871 Set_Ekind (Derived_Type, E_Array_Type);
4873 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
4874 Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type);
4876 Set_Has_Delayed_Freeze (Derived_Type, True);
4880 Set_Etype (Derived_Type, Implicit_Base);
4883 Make_Subtype_Declaration (Loc,
4884 Defining_Identifier => Derived_Type,
4885 Subtype_Indication =>
4886 Make_Subtype_Indication (Loc,
4887 Subtype_Mark => New_Reference_To (Implicit_Base, Loc),
4888 Constraint => Constraint (Indic)));
4890 Rewrite (N, New_Indic);
4895 if Nkind (Indic) /= N_Subtype_Indication then
4898 Set_Ekind (Derived_Type, Ekind (Parent_Type));
4899 Set_Etype (Derived_Type, Implicit_Base);
4900 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
4903 Error_Msg_N ("illegal constraint on constrained type", Indic);
4907 -- If parent type is not a derived type itself, and is declared in
4908 -- closed scope (e.g. a subprogram), then we must explicitly introduce
4909 -- the new type's concatenation operator since Derive_Subprograms
4910 -- will not inherit the parent's operator. If the parent type is
4911 -- unconstrained, the operator is of the unconstrained base type.
4913 if Number_Dimensions (Parent_Type) = 1
4914 and then not Is_Limited_Type (Parent_Type)
4915 and then not Is_Derived_Type (Parent_Type)
4916 and then not Is_Package_Or_Generic_Package
4917 (Scope (Base_Type (Parent_Type)))
4919 if not Is_Constrained (Parent_Type)
4920 and then Is_Constrained (Derived_Type)
4922 New_Concatenation_Op (Implicit_Base);
4924 New_Concatenation_Op (Derived_Type);
4927 end Build_Derived_Array_Type;
4929 -----------------------------------
4930 -- Build_Derived_Concurrent_Type --
4931 -----------------------------------
4933 procedure Build_Derived_Concurrent_Type
4935 Parent_Type : Entity_Id;
4936 Derived_Type : Entity_Id)
4938 Loc : constant Source_Ptr := Sloc (N);
4940 Corr_Record : constant Entity_Id := Make_Temporary (Loc, 'C');
4941 Corr_Decl : Node_Id;
4942 Corr_Decl_Needed : Boolean;
4943 -- If the derived type has fewer discriminants than its parent, the
4944 -- corresponding record is also a derived type, in order to account for
4945 -- the bound discriminants. We create a full type declaration for it in
4948 Constraint_Present : constant Boolean :=
4949 Nkind (Subtype_Indication (Type_Definition (N))) =
4950 N_Subtype_Indication;
4952 D_Constraint : Node_Id;
4953 New_Constraint : Elist_Id;
4954 Old_Disc : Entity_Id;
4955 New_Disc : Entity_Id;
4959 Set_Stored_Constraint (Derived_Type, No_Elist);
4960 Corr_Decl_Needed := False;
4963 if Present (Discriminant_Specifications (N))
4964 and then Constraint_Present
4966 Old_Disc := First_Discriminant (Parent_Type);
4967 New_Disc := First (Discriminant_Specifications (N));
4968 while Present (New_Disc) and then Present (Old_Disc) loop
4969 Next_Discriminant (Old_Disc);
4974 if Present (Old_Disc) then
4976 -- The new type has fewer discriminants, so we need to create a new
4977 -- corresponding record, which is derived from the corresponding
4978 -- record of the parent, and has a stored constraint that captures
4979 -- the values of the discriminant constraints.
4981 -- The type declaration for the derived corresponding record has
4982 -- the same discriminant part and constraints as the current
4983 -- declaration. Copy the unanalyzed tree to build declaration.
4985 Corr_Decl_Needed := True;
4986 New_N := Copy_Separate_Tree (N);
4989 Make_Full_Type_Declaration (Loc,
4990 Defining_Identifier => Corr_Record,
4991 Discriminant_Specifications =>
4992 Discriminant_Specifications (New_N),
4994 Make_Derived_Type_Definition (Loc,
4995 Subtype_Indication =>
4996 Make_Subtype_Indication (Loc,
4999 (Corresponding_Record_Type (Parent_Type), Loc),
5002 (Subtype_Indication (Type_Definition (New_N))))));
5005 -- Copy Storage_Size and Relative_Deadline variables if task case
5007 if Is_Task_Type (Parent_Type) then
5008 Set_Storage_Size_Variable (Derived_Type,
5009 Storage_Size_Variable (Parent_Type));
5010 Set_Relative_Deadline_Variable (Derived_Type,
5011 Relative_Deadline_Variable (Parent_Type));
5014 if Present (Discriminant_Specifications (N)) then
5015 Push_Scope (Derived_Type);
5016 Check_Or_Process_Discriminants (N, Derived_Type);
5018 if Constraint_Present then
5020 Expand_To_Stored_Constraint
5022 Build_Discriminant_Constraints
5024 Subtype_Indication (Type_Definition (N)), True));
5029 elsif Constraint_Present then
5031 -- Build constrained subtype and derive from it
5034 Loc : constant Source_Ptr := Sloc (N);
5035 Anon : constant Entity_Id :=
5036 Make_Defining_Identifier (Loc,
5037 New_External_Name (Chars (Derived_Type), 'T'));
5042 Make_Subtype_Declaration (Loc,
5043 Defining_Identifier => Anon,
5044 Subtype_Indication =>
5045 Subtype_Indication (Type_Definition (N)));
5046 Insert_Before (N, Decl);
5049 Rewrite (Subtype_Indication (Type_Definition (N)),
5050 New_Occurrence_Of (Anon, Loc));
5051 Set_Analyzed (Derived_Type, False);
5057 -- By default, operations and private data are inherited from parent.
5058 -- However, in the presence of bound discriminants, a new corresponding
5059 -- record will be created, see below.
5061 Set_Has_Discriminants
5062 (Derived_Type, Has_Discriminants (Parent_Type));
5063 Set_Corresponding_Record_Type
5064 (Derived_Type, Corresponding_Record_Type (Parent_Type));
5066 -- Is_Constrained is set according the parent subtype, but is set to
5067 -- False if the derived type is declared with new discriminants.
5071 (Is_Constrained (Parent_Type) or else Constraint_Present)
5072 and then not Present (Discriminant_Specifications (N)));
5074 if Constraint_Present then
5075 if not Has_Discriminants (Parent_Type) then
5076 Error_Msg_N ("untagged parent must have discriminants", N);
5078 elsif Present (Discriminant_Specifications (N)) then
5080 -- Verify that new discriminants are used to constrain old ones
5085 (Constraint (Subtype_Indication (Type_Definition (N)))));
5087 Old_Disc := First_Discriminant (Parent_Type);
5089 while Present (D_Constraint) loop
5090 if Nkind (D_Constraint) /= N_Discriminant_Association then
5092 -- Positional constraint. If it is a reference to a new
5093 -- discriminant, it constrains the corresponding old one.
5095 if Nkind (D_Constraint) = N_Identifier then
5096 New_Disc := First_Discriminant (Derived_Type);
5097 while Present (New_Disc) loop
5098 exit when Chars (New_Disc) = Chars (D_Constraint);
5099 Next_Discriminant (New_Disc);
5102 if Present (New_Disc) then
5103 Set_Corresponding_Discriminant (New_Disc, Old_Disc);
5107 Next_Discriminant (Old_Disc);
5109 -- if this is a named constraint, search by name for the old
5110 -- discriminants constrained by the new one.
5112 elsif Nkind (Expression (D_Constraint)) = N_Identifier then
5114 -- Find new discriminant with that name
5116 New_Disc := First_Discriminant (Derived_Type);
5117 while Present (New_Disc) loop
5119 Chars (New_Disc) = Chars (Expression (D_Constraint));
5120 Next_Discriminant (New_Disc);
5123 if Present (New_Disc) then
5125 -- Verify that new discriminant renames some discriminant
5126 -- of the parent type, and associate the new discriminant
5127 -- with one or more old ones that it renames.
5133 Selector := First (Selector_Names (D_Constraint));
5134 while Present (Selector) loop
5135 Old_Disc := First_Discriminant (Parent_Type);
5136 while Present (Old_Disc) loop
5137 exit when Chars (Old_Disc) = Chars (Selector);
5138 Next_Discriminant (Old_Disc);
5141 if Present (Old_Disc) then
5142 Set_Corresponding_Discriminant
5143 (New_Disc, Old_Disc);
5152 Next (D_Constraint);
5155 New_Disc := First_Discriminant (Derived_Type);
5156 while Present (New_Disc) loop
5157 if No (Corresponding_Discriminant (New_Disc)) then
5159 ("new discriminant& must constrain old one", N, New_Disc);
5162 Subtypes_Statically_Compatible
5164 Etype (Corresponding_Discriminant (New_Disc)))
5167 ("& not statically compatible with parent discriminant",
5171 Next_Discriminant (New_Disc);
5175 elsif Present (Discriminant_Specifications (N)) then
5177 ("missing discriminant constraint in untagged derivation", N);
5180 -- The entity chain of the derived type includes the new discriminants
5181 -- but shares operations with the parent.
5183 if Present (Discriminant_Specifications (N)) then
5184 Old_Disc := First_Discriminant (Parent_Type);
5185 while Present (Old_Disc) loop
5186 if No (Next_Entity (Old_Disc))
5187 or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant
5190 (Last_Entity (Derived_Type), Next_Entity (Old_Disc));
5194 Next_Discriminant (Old_Disc);
5198 Set_First_Entity (Derived_Type, First_Entity (Parent_Type));
5199 if Has_Discriminants (Parent_Type) then
5200 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
5201 Set_Discriminant_Constraint (
5202 Derived_Type, Discriminant_Constraint (Parent_Type));
5206 Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type));
5208 Set_Has_Completion (Derived_Type);
5210 if Corr_Decl_Needed then
5211 Set_Stored_Constraint (Derived_Type, New_Constraint);
5212 Insert_After (N, Corr_Decl);
5213 Analyze (Corr_Decl);
5214 Set_Corresponding_Record_Type (Derived_Type, Corr_Record);
5216 end Build_Derived_Concurrent_Type;
5218 ------------------------------------
5219 -- Build_Derived_Enumeration_Type --
5220 ------------------------------------
5222 procedure Build_Derived_Enumeration_Type
5224 Parent_Type : Entity_Id;
5225 Derived_Type : Entity_Id)
5227 Loc : constant Source_Ptr := Sloc (N);
5228 Def : constant Node_Id := Type_Definition (N);
5229 Indic : constant Node_Id := Subtype_Indication (Def);
5230 Implicit_Base : Entity_Id;
5231 Literal : Entity_Id;
5232 New_Lit : Entity_Id;
5233 Literals_List : List_Id;
5234 Type_Decl : Node_Id;
5236 Rang_Expr : Node_Id;
5239 -- Since types Standard.Character and Standard.[Wide_]Wide_Character do
5240 -- not have explicit literals lists we need to process types derived
5241 -- from them specially. This is handled by Derived_Standard_Character.
5242 -- If the parent type is a generic type, there are no literals either,
5243 -- and we construct the same skeletal representation as for the generic
5246 if Is_Standard_Character_Type (Parent_Type) then
5247 Derived_Standard_Character (N, Parent_Type, Derived_Type);
5249 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
5255 if Nkind (Indic) /= N_Subtype_Indication then
5257 Make_Attribute_Reference (Loc,
5258 Attribute_Name => Name_First,
5259 Prefix => New_Reference_To (Derived_Type, Loc));
5260 Set_Etype (Lo, Derived_Type);
5263 Make_Attribute_Reference (Loc,
5264 Attribute_Name => Name_Last,
5265 Prefix => New_Reference_To (Derived_Type, Loc));
5266 Set_Etype (Hi, Derived_Type);
5268 Set_Scalar_Range (Derived_Type,
5274 -- Analyze subtype indication and verify compatibility
5275 -- with parent type.
5277 if Base_Type (Process_Subtype (Indic, N)) /=
5278 Base_Type (Parent_Type)
5281 ("illegal constraint for formal discrete type", N);
5287 -- If a constraint is present, analyze the bounds to catch
5288 -- premature usage of the derived literals.
5290 if Nkind (Indic) = N_Subtype_Indication
5291 and then Nkind (Range_Expression (Constraint (Indic))) = N_Range
5293 Analyze (Low_Bound (Range_Expression (Constraint (Indic))));
5294 Analyze (High_Bound (Range_Expression (Constraint (Indic))));
5297 -- Introduce an implicit base type for the derived type even if there
5298 -- is no constraint attached to it, since this seems closer to the
5299 -- Ada semantics. Build a full type declaration tree for the derived
5300 -- type using the implicit base type as the defining identifier. The
5301 -- build a subtype declaration tree which applies the constraint (if
5302 -- any) have it replace the derived type declaration.
5304 Literal := First_Literal (Parent_Type);
5305 Literals_List := New_List;
5306 while Present (Literal)
5307 and then Ekind (Literal) = E_Enumeration_Literal
5309 -- Literals of the derived type have the same representation as
5310 -- those of the parent type, but this representation can be
5311 -- overridden by an explicit representation clause. Indicate
5312 -- that there is no explicit representation given yet. These
5313 -- derived literals are implicit operations of the new type,
5314 -- and can be overridden by explicit ones.
5316 if Nkind (Literal) = N_Defining_Character_Literal then
5318 Make_Defining_Character_Literal (Loc, Chars (Literal));
5320 New_Lit := Make_Defining_Identifier (Loc, Chars (Literal));
5323 Set_Ekind (New_Lit, E_Enumeration_Literal);
5324 Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal));
5325 Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal));
5326 Set_Enumeration_Rep_Expr (New_Lit, Empty);
5327 Set_Alias (New_Lit, Literal);
5328 Set_Is_Known_Valid (New_Lit, True);
5330 Append (New_Lit, Literals_List);
5331 Next_Literal (Literal);
5335 Make_Defining_Identifier (Sloc (Derived_Type),
5336 New_External_Name (Chars (Derived_Type), 'B'));
5338 -- Indicate the proper nature of the derived type. This must be done
5339 -- before analysis of the literals, to recognize cases when a literal
5340 -- may be hidden by a previous explicit function definition (cf.
5343 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
5344 Set_Etype (Derived_Type, Implicit_Base);
5347 Make_Full_Type_Declaration (Loc,
5348 Defining_Identifier => Implicit_Base,
5349 Discriminant_Specifications => No_List,
5351 Make_Enumeration_Type_Definition (Loc, Literals_List));
5353 Mark_Rewrite_Insertion (Type_Decl);
5354 Insert_Before (N, Type_Decl);
5355 Analyze (Type_Decl);
5357 -- After the implicit base is analyzed its Etype needs to be changed
5358 -- to reflect the fact that it is derived from the parent type which
5359 -- was ignored during analysis. We also set the size at this point.
5361 Set_Etype (Implicit_Base, Parent_Type);
5363 Set_Size_Info (Implicit_Base, Parent_Type);
5364 Set_RM_Size (Implicit_Base, RM_Size (Parent_Type));
5365 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type));
5367 Set_Has_Non_Standard_Rep
5368 (Implicit_Base, Has_Non_Standard_Rep
5370 Set_Has_Delayed_Freeze (Implicit_Base);
5372 -- Process the subtype indication including a validation check on the
5373 -- constraint, if any. If a constraint is given, its bounds must be
5374 -- implicitly converted to the new type.
5376 if Nkind (Indic) = N_Subtype_Indication then
5378 R : constant Node_Id :=
5379 Range_Expression (Constraint (Indic));
5382 if Nkind (R) = N_Range then
5383 Hi := Build_Scalar_Bound
5384 (High_Bound (R), Parent_Type, Implicit_Base);
5385 Lo := Build_Scalar_Bound
5386 (Low_Bound (R), Parent_Type, Implicit_Base);
5389 -- Constraint is a Range attribute. Replace with explicit
5390 -- mention of the bounds of the prefix, which must be a
5393 Analyze (Prefix (R));
5395 Convert_To (Implicit_Base,
5396 Make_Attribute_Reference (Loc,
5397 Attribute_Name => Name_Last,
5399 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
5402 Convert_To (Implicit_Base,
5403 Make_Attribute_Reference (Loc,
5404 Attribute_Name => Name_First,
5406 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
5413 (Type_High_Bound (Parent_Type),
5414 Parent_Type, Implicit_Base);
5417 (Type_Low_Bound (Parent_Type),
5418 Parent_Type, Implicit_Base);
5426 -- If we constructed a default range for the case where no range
5427 -- was given, then the expressions in the range must not freeze
5428 -- since they do not correspond to expressions in the source.
5430 if Nkind (Indic) /= N_Subtype_Indication then
5431 Set_Must_Not_Freeze (Lo);
5432 Set_Must_Not_Freeze (Hi);
5433 Set_Must_Not_Freeze (Rang_Expr);
5437 Make_Subtype_Declaration (Loc,
5438 Defining_Identifier => Derived_Type,
5439 Subtype_Indication =>
5440 Make_Subtype_Indication (Loc,
5441 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
5443 Make_Range_Constraint (Loc,
5444 Range_Expression => Rang_Expr))));
5448 -- If pragma Discard_Names applies on the first subtype of the parent
5449 -- type, then it must be applied on this subtype as well.
5451 if Einfo.Discard_Names (First_Subtype (Parent_Type)) then
5452 Set_Discard_Names (Derived_Type);
5455 -- Apply a range check. Since this range expression doesn't have an
5456 -- Etype, we have to specifically pass the Source_Typ parameter. Is
5459 if Nkind (Indic) = N_Subtype_Indication then
5460 Apply_Range_Check (Range_Expression (Constraint (Indic)),
5462 Source_Typ => Entity (Subtype_Mark (Indic)));
5465 end Build_Derived_Enumeration_Type;
5467 --------------------------------
5468 -- Build_Derived_Numeric_Type --
5469 --------------------------------
5471 procedure Build_Derived_Numeric_Type
5473 Parent_Type : Entity_Id;
5474 Derived_Type : Entity_Id)
5476 Loc : constant Source_Ptr := Sloc (N);
5477 Tdef : constant Node_Id := Type_Definition (N);
5478 Indic : constant Node_Id := Subtype_Indication (Tdef);
5479 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
5480 No_Constraint : constant Boolean := Nkind (Indic) /=
5481 N_Subtype_Indication;
5482 Implicit_Base : Entity_Id;
5488 -- Process the subtype indication including a validation check on
5489 -- the constraint if any.
5491 Discard_Node (Process_Subtype (Indic, N));
5493 -- Introduce an implicit base type for the derived type even if there
5494 -- is no constraint attached to it, since this seems closer to the Ada
5498 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
5500 Set_Etype (Implicit_Base, Parent_Base);
5501 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
5502 Set_Size_Info (Implicit_Base, Parent_Base);
5503 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base));
5504 Set_Parent (Implicit_Base, Parent (Derived_Type));
5505 Set_Is_Known_Valid (Implicit_Base, Is_Known_Valid (Parent_Base));
5507 -- Set RM Size for discrete type or decimal fixed-point type
5508 -- Ordinary fixed-point is excluded, why???
5510 if Is_Discrete_Type (Parent_Base)
5511 or else Is_Decimal_Fixed_Point_Type (Parent_Base)
5513 Set_RM_Size (Implicit_Base, RM_Size (Parent_Base));
5516 Set_Has_Delayed_Freeze (Implicit_Base);
5518 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
5519 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
5521 Set_Scalar_Range (Implicit_Base,
5526 if Has_Infinities (Parent_Base) then
5527 Set_Includes_Infinities (Scalar_Range (Implicit_Base));
5530 -- The Derived_Type, which is the entity of the declaration, is a
5531 -- subtype of the implicit base. Its Ekind is a subtype, even in the
5532 -- absence of an explicit constraint.
5534 Set_Etype (Derived_Type, Implicit_Base);
5536 -- If we did not have a constraint, then the Ekind is set from the
5537 -- parent type (otherwise Process_Subtype has set the bounds)
5539 if No_Constraint then
5540 Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type)));
5543 -- If we did not have a range constraint, then set the range from the
5544 -- parent type. Otherwise, the call to Process_Subtype has set the
5548 or else not Has_Range_Constraint (Indic)
5550 Set_Scalar_Range (Derived_Type,
5552 Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)),
5553 High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type))));
5554 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
5556 if Has_Infinities (Parent_Type) then
5557 Set_Includes_Infinities (Scalar_Range (Derived_Type));
5560 Set_Is_Known_Valid (Derived_Type, Is_Known_Valid (Parent_Type));
5563 Set_Is_Descendent_Of_Address (Derived_Type,
5564 Is_Descendent_Of_Address (Parent_Type));
5565 Set_Is_Descendent_Of_Address (Implicit_Base,
5566 Is_Descendent_Of_Address (Parent_Type));
5568 -- Set remaining type-specific fields, depending on numeric type
5570 if Is_Modular_Integer_Type (Parent_Type) then
5571 Set_Modulus (Implicit_Base, Modulus (Parent_Base));
5573 Set_Non_Binary_Modulus
5574 (Implicit_Base, Non_Binary_Modulus (Parent_Base));
5577 (Implicit_Base, Is_Known_Valid (Parent_Base));
5579 elsif Is_Floating_Point_Type (Parent_Type) then
5581 -- Digits of base type is always copied from the digits value of
5582 -- the parent base type, but the digits of the derived type will
5583 -- already have been set if there was a constraint present.
5585 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
5586 Set_Vax_Float (Implicit_Base, Vax_Float (Parent_Base));
5588 if No_Constraint then
5589 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type));
5592 elsif Is_Fixed_Point_Type (Parent_Type) then
5594 -- Small of base type and derived type are always copied from the
5595 -- parent base type, since smalls never change. The delta of the
5596 -- base type is also copied from the parent base type. However the
5597 -- delta of the derived type will have been set already if a
5598 -- constraint was present.
5600 Set_Small_Value (Derived_Type, Small_Value (Parent_Base));
5601 Set_Small_Value (Implicit_Base, Small_Value (Parent_Base));
5602 Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base));
5604 if No_Constraint then
5605 Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type));
5608 -- The scale and machine radix in the decimal case are always
5609 -- copied from the parent base type.
5611 if Is_Decimal_Fixed_Point_Type (Parent_Type) then
5612 Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base));
5613 Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base));
5615 Set_Machine_Radix_10
5616 (Derived_Type, Machine_Radix_10 (Parent_Base));
5617 Set_Machine_Radix_10
5618 (Implicit_Base, Machine_Radix_10 (Parent_Base));
5620 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
5622 if No_Constraint then
5623 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base));
5626 -- the analysis of the subtype_indication sets the
5627 -- digits value of the derived type.
5634 -- The type of the bounds is that of the parent type, and they
5635 -- must be converted to the derived type.
5637 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
5639 -- The implicit_base should be frozen when the derived type is frozen,
5640 -- but note that it is used in the conversions of the bounds. For fixed
5641 -- types we delay the determination of the bounds until the proper
5642 -- freezing point. For other numeric types this is rejected by GCC, for
5643 -- reasons that are currently unclear (???), so we choose to freeze the
5644 -- implicit base now. In the case of integers and floating point types
5645 -- this is harmless because subsequent representation clauses cannot
5646 -- affect anything, but it is still baffling that we cannot use the
5647 -- same mechanism for all derived numeric types.
5649 -- There is a further complication: actually *some* representation
5650 -- clauses can affect the implicit base type. Namely, attribute
5651 -- definition clauses for stream-oriented attributes need to set the
5652 -- corresponding TSS entries on the base type, and this normally cannot
5653 -- be done after the base type is frozen, so the circuitry in
5654 -- Sem_Ch13.New_Stream_Subprogram must account for this possibility and
5655 -- not use Set_TSS in this case.
5657 if Is_Fixed_Point_Type (Parent_Type) then
5658 Conditional_Delay (Implicit_Base, Parent_Type);
5660 Freeze_Before (N, Implicit_Base);
5662 end Build_Derived_Numeric_Type;
5664 --------------------------------
5665 -- Build_Derived_Private_Type --
5666 --------------------------------
5668 procedure Build_Derived_Private_Type
5670 Parent_Type : Entity_Id;
5671 Derived_Type : Entity_Id;
5672 Is_Completion : Boolean;
5673 Derive_Subps : Boolean := True)
5675 Loc : constant Source_Ptr := Sloc (N);
5676 Der_Base : Entity_Id;
5678 Full_Decl : Node_Id := Empty;
5679 Full_Der : Entity_Id;
5681 Last_Discr : Entity_Id;
5682 Par_Scope : constant Entity_Id := Scope (Base_Type (Parent_Type));
5683 Swapped : Boolean := False;
5685 procedure Copy_And_Build;
5686 -- Copy derived type declaration, replace parent with its full view,
5687 -- and analyze new declaration.
5689 --------------------
5690 -- Copy_And_Build --
5691 --------------------
5693 procedure Copy_And_Build is
5697 if Ekind (Parent_Type) in Record_Kind
5699 (Ekind (Parent_Type) in Enumeration_Kind
5700 and then not Is_Standard_Character_Type (Parent_Type)
5701 and then not Is_Generic_Type (Root_Type (Parent_Type)))
5703 Full_N := New_Copy_Tree (N);
5704 Insert_After (N, Full_N);
5705 Build_Derived_Type (
5706 Full_N, Parent_Type, Full_Der, True, Derive_Subps => False);
5709 Build_Derived_Type (
5710 N, Parent_Type, Full_Der, True, Derive_Subps => False);
5714 -- Start of processing for Build_Derived_Private_Type
5717 if Is_Tagged_Type (Parent_Type) then
5718 Full_P := Full_View (Parent_Type);
5720 -- A type extension of a type with unknown discriminants is an
5721 -- indefinite type that the back-end cannot handle directly.
5722 -- We treat it as a private type, and build a completion that is
5723 -- derived from the full view of the parent, and hopefully has
5724 -- known discriminants.
5726 -- If the full view of the parent type has an underlying record view,
5727 -- use it to generate the underlying record view of this derived type
5728 -- (required for chains of derivations with unknown discriminants).
5730 -- Minor optimization: we avoid the generation of useless underlying
5731 -- record view entities if the private type declaration has unknown
5732 -- discriminants but its corresponding full view has no
5735 if Has_Unknown_Discriminants (Parent_Type)
5736 and then Present (Full_P)
5737 and then (Has_Discriminants (Full_P)
5738 or else Present (Underlying_Record_View (Full_P)))
5739 and then not In_Open_Scopes (Par_Scope)
5740 and then Expander_Active
5743 Full_Der : constant Entity_Id := Make_Temporary (Loc, 'T');
5744 New_Ext : constant Node_Id :=
5746 (Record_Extension_Part (Type_Definition (N)));
5750 Build_Derived_Record_Type
5751 (N, Parent_Type, Derived_Type, Derive_Subps);
5753 -- Build anonymous completion, as a derivation from the full
5754 -- view of the parent. This is not a completion in the usual
5755 -- sense, because the current type is not private.
5758 Make_Full_Type_Declaration (Loc,
5759 Defining_Identifier => Full_Der,
5761 Make_Derived_Type_Definition (Loc,
5762 Subtype_Indication =>
5764 (Subtype_Indication (Type_Definition (N))),
5765 Record_Extension_Part => New_Ext));
5767 -- If the parent type has an underlying record view, use it
5768 -- here to build the new underlying record view.
5770 if Present (Underlying_Record_View (Full_P)) then
5772 (Nkind (Subtype_Indication (Type_Definition (Decl)))
5774 Set_Entity (Subtype_Indication (Type_Definition (Decl)),
5775 Underlying_Record_View (Full_P));
5778 Install_Private_Declarations (Par_Scope);
5779 Install_Visible_Declarations (Par_Scope);
5780 Insert_Before (N, Decl);
5782 -- Mark entity as an underlying record view before analysis,
5783 -- to avoid generating the list of its primitive operations
5784 -- (which is not really required for this entity) and thus
5785 -- prevent spurious errors associated with missing overriding
5786 -- of abstract primitives (overridden only for Derived_Type).
5788 Set_Ekind (Full_Der, E_Record_Type);
5789 Set_Is_Underlying_Record_View (Full_Der);
5793 pragma Assert (Has_Discriminants (Full_Der)
5794 and then not Has_Unknown_Discriminants (Full_Der));
5796 Uninstall_Declarations (Par_Scope);
5798 -- Freeze the underlying record view, to prevent generation of
5799 -- useless dispatching information, which is simply shared with
5800 -- the real derived type.
5802 Set_Is_Frozen (Full_Der);
5804 -- Set up links between real entity and underlying record view
5806 Set_Underlying_Record_View (Derived_Type, Base_Type (Full_Der));
5807 Set_Underlying_Record_View (Base_Type (Full_Der), Derived_Type);
5810 -- If discriminants are known, build derived record
5813 Build_Derived_Record_Type
5814 (N, Parent_Type, Derived_Type, Derive_Subps);
5819 elsif Has_Discriminants (Parent_Type) then
5820 if Present (Full_View (Parent_Type)) then
5821 if not Is_Completion then
5823 -- Copy declaration for subsequent analysis, to provide a
5824 -- completion for what is a private declaration. Indicate that
5825 -- the full type is internally generated.
5827 Full_Decl := New_Copy_Tree (N);
5828 Full_Der := New_Copy (Derived_Type);
5829 Set_Comes_From_Source (Full_Decl, False);
5830 Set_Comes_From_Source (Full_Der, False);
5832 Insert_After (N, Full_Decl);
5835 -- If this is a completion, the full view being built is itself
5836 -- private. We build a subtype of the parent with the same
5837 -- constraints as this full view, to convey to the back end the
5838 -- constrained components and the size of this subtype. If the
5839 -- parent is constrained, its full view can serve as the
5840 -- underlying full view of the derived type.
5842 if No (Discriminant_Specifications (N)) then
5843 if Nkind (Subtype_Indication (Type_Definition (N))) =
5844 N_Subtype_Indication
5846 Build_Underlying_Full_View (N, Derived_Type, Parent_Type);
5848 elsif Is_Constrained (Full_View (Parent_Type)) then
5849 Set_Underlying_Full_View
5850 (Derived_Type, Full_View (Parent_Type));
5854 -- If there are new discriminants, the parent subtype is
5855 -- constrained by them, but it is not clear how to build
5856 -- the Underlying_Full_View in this case???
5863 -- Build partial view of derived type from partial view of parent
5865 Build_Derived_Record_Type
5866 (N, Parent_Type, Derived_Type, Derive_Subps);
5868 if Present (Full_View (Parent_Type)) and then not Is_Completion then
5869 if not In_Open_Scopes (Par_Scope)
5870 or else not In_Same_Source_Unit (N, Parent_Type)
5872 -- Swap partial and full views temporarily
5874 Install_Private_Declarations (Par_Scope);
5875 Install_Visible_Declarations (Par_Scope);
5879 -- Build full view of derived type from full view of parent which
5880 -- is now installed. Subprograms have been derived on the partial
5881 -- view, the completion does not derive them anew.
5883 if not Is_Tagged_Type (Parent_Type) then
5885 -- If the parent is itself derived from another private type,
5886 -- installing the private declarations has not affected its
5887 -- privacy status, so use its own full view explicitly.
5889 if Is_Private_Type (Parent_Type) then
5890 Build_Derived_Record_Type
5891 (Full_Decl, Full_View (Parent_Type), Full_Der, False);
5893 Build_Derived_Record_Type
5894 (Full_Decl, Parent_Type, Full_Der, False);
5898 -- If full view of parent is tagged, the completion inherits
5899 -- the proper primitive operations.
5901 Set_Defining_Identifier (Full_Decl, Full_Der);
5902 Build_Derived_Record_Type
5903 (Full_Decl, Parent_Type, Full_Der, Derive_Subps);
5904 Set_Analyzed (Full_Decl);
5908 Uninstall_Declarations (Par_Scope);
5910 if In_Open_Scopes (Par_Scope) then
5911 Install_Visible_Declarations (Par_Scope);
5915 Der_Base := Base_Type (Derived_Type);
5916 Set_Full_View (Derived_Type, Full_Der);
5917 Set_Full_View (Der_Base, Base_Type (Full_Der));
5919 -- Copy the discriminant list from full view to the partial views
5920 -- (base type and its subtype). Gigi requires that the partial and
5921 -- full views have the same discriminants.
5923 -- Note that since the partial view is pointing to discriminants
5924 -- in the full view, their scope will be that of the full view.
5925 -- This might cause some front end problems and need adjustment???
5927 Discr := First_Discriminant (Base_Type (Full_Der));
5928 Set_First_Entity (Der_Base, Discr);
5931 Last_Discr := Discr;
5932 Next_Discriminant (Discr);
5933 exit when No (Discr);
5936 Set_Last_Entity (Der_Base, Last_Discr);
5938 Set_First_Entity (Derived_Type, First_Entity (Der_Base));
5939 Set_Last_Entity (Derived_Type, Last_Entity (Der_Base));
5940 Set_Stored_Constraint (Full_Der, Stored_Constraint (Derived_Type));
5943 -- If this is a completion, the derived type stays private and
5944 -- there is no need to create a further full view, except in the
5945 -- unusual case when the derivation is nested within a child unit,
5951 elsif Present (Full_View (Parent_Type))
5952 and then Has_Discriminants (Full_View (Parent_Type))
5954 if Has_Unknown_Discriminants (Parent_Type)
5955 and then Nkind (Subtype_Indication (Type_Definition (N))) =
5956 N_Subtype_Indication
5959 ("cannot constrain type with unknown discriminants",
5960 Subtype_Indication (Type_Definition (N)));
5964 -- If full view of parent is a record type, build full view as a
5965 -- derivation from the parent's full view. Partial view remains
5966 -- private. For code generation and linking, the full view must have
5967 -- the same public status as the partial one. This full view is only
5968 -- needed if the parent type is in an enclosing scope, so that the
5969 -- full view may actually become visible, e.g. in a child unit. This
5970 -- is both more efficient, and avoids order of freezing problems with
5971 -- the added entities.
5973 if not Is_Private_Type (Full_View (Parent_Type))
5974 and then (In_Open_Scopes (Scope (Parent_Type)))
5976 Full_Der := Make_Defining_Identifier (Sloc (Derived_Type),
5977 Chars (Derived_Type));
5978 Set_Is_Itype (Full_Der);
5979 Set_Has_Private_Declaration (Full_Der);
5980 Set_Has_Private_Declaration (Derived_Type);
5981 Set_Associated_Node_For_Itype (Full_Der, N);
5982 Set_Parent (Full_Der, Parent (Derived_Type));
5983 Set_Full_View (Derived_Type, Full_Der);
5984 Set_Is_Public (Full_Der, Is_Public (Derived_Type));
5985 Full_P := Full_View (Parent_Type);
5986 Exchange_Declarations (Parent_Type);
5988 Exchange_Declarations (Full_P);
5991 Build_Derived_Record_Type
5992 (N, Full_View (Parent_Type), Derived_Type,
5993 Derive_Subps => False);
5996 -- In any case, the primitive operations are inherited from the
5997 -- parent type, not from the internal full view.
5999 Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type));
6001 if Derive_Subps then
6002 Derive_Subprograms (Parent_Type, Derived_Type);
6006 -- Untagged type, No discriminants on either view
6008 if Nkind (Subtype_Indication (Type_Definition (N))) =
6009 N_Subtype_Indication
6012 ("illegal constraint on type without discriminants", N);
6015 if Present (Discriminant_Specifications (N))
6016 and then Present (Full_View (Parent_Type))
6017 and then not Is_Tagged_Type (Full_View (Parent_Type))
6019 Error_Msg_N ("cannot add discriminants to untagged type", N);
6022 Set_Stored_Constraint (Derived_Type, No_Elist);
6023 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6024 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
6025 Set_Has_Controlled_Component
6026 (Derived_Type, Has_Controlled_Component
6029 -- Direct controlled types do not inherit Finalize_Storage_Only flag
6031 if not Is_Controlled (Parent_Type) then
6032 Set_Finalize_Storage_Only
6033 (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type));
6036 -- Construct the implicit full view by deriving from full view of the
6037 -- parent type. In order to get proper visibility, we install the
6038 -- parent scope and its declarations.
6040 -- ??? If the parent is untagged private and its completion is
6041 -- tagged, this mechanism will not work because we cannot derive from
6042 -- the tagged full view unless we have an extension.
6044 if Present (Full_View (Parent_Type))
6045 and then not Is_Tagged_Type (Full_View (Parent_Type))
6046 and then not Is_Completion
6049 Make_Defining_Identifier (Sloc (Derived_Type),
6050 Chars => Chars (Derived_Type));
6051 Set_Is_Itype (Full_Der);
6052 Set_Has_Private_Declaration (Full_Der);
6053 Set_Has_Private_Declaration (Derived_Type);
6054 Set_Associated_Node_For_Itype (Full_Der, N);
6055 Set_Parent (Full_Der, Parent (Derived_Type));
6056 Set_Full_View (Derived_Type, Full_Der);
6058 if not In_Open_Scopes (Par_Scope) then
6059 Install_Private_Declarations (Par_Scope);
6060 Install_Visible_Declarations (Par_Scope);
6062 Uninstall_Declarations (Par_Scope);
6064 -- If parent scope is open and in another unit, and parent has a
6065 -- completion, then the derivation is taking place in the visible
6066 -- part of a child unit. In that case retrieve the full view of
6067 -- the parent momentarily.
6069 elsif not In_Same_Source_Unit (N, Parent_Type) then
6070 Full_P := Full_View (Parent_Type);
6071 Exchange_Declarations (Parent_Type);
6073 Exchange_Declarations (Full_P);
6075 -- Otherwise it is a local derivation
6081 Set_Scope (Full_Der, Current_Scope);
6082 Set_Is_First_Subtype (Full_Der,
6083 Is_First_Subtype (Derived_Type));
6084 Set_Has_Size_Clause (Full_Der, False);
6085 Set_Has_Alignment_Clause (Full_Der, False);
6086 Set_Next_Entity (Full_Der, Empty);
6087 Set_Has_Delayed_Freeze (Full_Der);
6088 Set_Is_Frozen (Full_Der, False);
6089 Set_Freeze_Node (Full_Der, Empty);
6090 Set_Depends_On_Private (Full_Der,
6091 Has_Private_Component (Full_Der));
6092 Set_Public_Status (Full_Der);
6096 Set_Has_Unknown_Discriminants (Derived_Type,
6097 Has_Unknown_Discriminants (Parent_Type));
6099 if Is_Private_Type (Derived_Type) then
6100 Set_Private_Dependents (Derived_Type, New_Elmt_List);
6103 if Is_Private_Type (Parent_Type)
6104 and then Base_Type (Parent_Type) = Parent_Type
6105 and then In_Open_Scopes (Scope (Parent_Type))
6107 Append_Elmt (Derived_Type, Private_Dependents (Parent_Type));
6109 if Is_Child_Unit (Scope (Current_Scope))
6110 and then Is_Completion
6111 and then In_Private_Part (Current_Scope)
6112 and then Scope (Parent_Type) /= Current_Scope
6114 -- This is the unusual case where a type completed by a private
6115 -- derivation occurs within a package nested in a child unit, and
6116 -- the parent is declared in an ancestor. In this case, the full
6117 -- view of the parent type will become visible in the body of
6118 -- the enclosing child, and only then will the current type be
6119 -- possibly non-private. We build a underlying full view that
6120 -- will be installed when the enclosing child body is compiled.
6123 Make_Defining_Identifier (Sloc (Derived_Type),
6124 Chars => Chars (Derived_Type));
6125 Set_Is_Itype (Full_Der);
6126 Build_Itype_Reference (Full_Der, N);
6128 -- The full view will be used to swap entities on entry/exit to
6129 -- the body, and must appear in the entity list for the package.
6131 Append_Entity (Full_Der, Scope (Derived_Type));
6132 Set_Has_Private_Declaration (Full_Der);
6133 Set_Has_Private_Declaration (Derived_Type);
6134 Set_Associated_Node_For_Itype (Full_Der, N);
6135 Set_Parent (Full_Der, Parent (Derived_Type));
6136 Full_P := Full_View (Parent_Type);
6137 Exchange_Declarations (Parent_Type);
6139 Exchange_Declarations (Full_P);
6140 Set_Underlying_Full_View (Derived_Type, Full_Der);
6143 end Build_Derived_Private_Type;
6145 -------------------------------
6146 -- Build_Derived_Record_Type --
6147 -------------------------------
6151 -- Ideally we would like to use the same model of type derivation for
6152 -- tagged and untagged record types. Unfortunately this is not quite
6153 -- possible because the semantics of representation clauses is different
6154 -- for tagged and untagged records under inheritance. Consider the
6157 -- type R (...) is [tagged] record ... end record;
6158 -- type T (...) is new R (...) [with ...];
6160 -- The representation clauses for T can specify a completely different
6161 -- record layout from R's. Hence the same component can be placed in two
6162 -- very different positions in objects of type T and R. If R and T are
6163 -- tagged types, representation clauses for T can only specify the layout
6164 -- of non inherited components, thus components that are common in R and T
6165 -- have the same position in objects of type R and T.
6167 -- This has two implications. The first is that the entire tree for R's
6168 -- declaration needs to be copied for T in the untagged case, so that T
6169 -- can be viewed as a record type of its own with its own representation
6170 -- clauses. The second implication is the way we handle discriminants.
6171 -- Specifically, in the untagged case we need a way to communicate to Gigi
6172 -- what are the real discriminants in the record, while for the semantics
6173 -- we need to consider those introduced by the user to rename the
6174 -- discriminants in the parent type. This is handled by introducing the
6175 -- notion of stored discriminants. See below for more.
6177 -- Fortunately the way regular components are inherited can be handled in
6178 -- the same way in tagged and untagged types.
6180 -- To complicate things a bit more the private view of a private extension
6181 -- cannot be handled in the same way as the full view (for one thing the
6182 -- semantic rules are somewhat different). We will explain what differs
6185 -- 2. DISCRIMINANTS UNDER INHERITANCE
6187 -- The semantic rules governing the discriminants of derived types are
6190 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
6191 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
6193 -- If parent type has discriminants, then the discriminants that are
6194 -- declared in the derived type are [3.4 (11)]:
6196 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
6199 -- o Otherwise, each discriminant of the parent type (implicitly declared
6200 -- in the same order with the same specifications). In this case, the
6201 -- discriminants are said to be "inherited", or if unknown in the parent
6202 -- are also unknown in the derived type.
6204 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
6206 -- o The parent subtype shall be constrained;
6208 -- o If the parent type is not a tagged type, then each discriminant of
6209 -- the derived type shall be used in the constraint defining a parent
6210 -- subtype. [Implementation note: This ensures that the new discriminant
6211 -- can share storage with an existing discriminant.]
6213 -- For the derived type each discriminant of the parent type is either
6214 -- inherited, constrained to equal some new discriminant of the derived
6215 -- type, or constrained to the value of an expression.
6217 -- When inherited or constrained to equal some new discriminant, the
6218 -- parent discriminant and the discriminant of the derived type are said
6221 -- If a discriminant of the parent type is constrained to a specific value
6222 -- in the derived type definition, then the discriminant is said to be
6223 -- "specified" by that derived type definition.
6225 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES
6227 -- We have spoken about stored discriminants in point 1 (introduction)
6228 -- above. There are two sort of stored discriminants: implicit and
6229 -- explicit. As long as the derived type inherits the same discriminants as
6230 -- the root record type, stored discriminants are the same as regular
6231 -- discriminants, and are said to be implicit. However, if any discriminant
6232 -- in the root type was renamed in the derived type, then the derived
6233 -- type will contain explicit stored discriminants. Explicit stored
6234 -- discriminants are discriminants in addition to the semantically visible
6235 -- discriminants defined for the derived type. Stored discriminants are
6236 -- used by Gigi to figure out what are the physical discriminants in
6237 -- objects of the derived type (see precise definition in einfo.ads).
6238 -- As an example, consider the following:
6240 -- type R (D1, D2, D3 : Int) is record ... end record;
6241 -- type T1 is new R;
6242 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
6243 -- type T3 is new T2;
6244 -- type T4 (Y : Int) is new T3 (Y, 99);
6246 -- The following table summarizes the discriminants and stored
6247 -- discriminants in R and T1 through T4.
6249 -- Type Discrim Stored Discrim Comment
6250 -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R
6251 -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1
6252 -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2
6253 -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3
6254 -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4
6256 -- Field Corresponding_Discriminant (abbreviated CD below) allows us to
6257 -- find the corresponding discriminant in the parent type, while
6258 -- Original_Record_Component (abbreviated ORC below), the actual physical
6259 -- component that is renamed. Finally the field Is_Completely_Hidden
6260 -- (abbreviated ICH below) is set for all explicit stored discriminants
6261 -- (see einfo.ads for more info). For the above example this gives:
6263 -- Discrim CD ORC ICH
6264 -- ^^^^^^^ ^^ ^^^ ^^^
6265 -- D1 in R empty itself no
6266 -- D2 in R empty itself no
6267 -- D3 in R empty itself no
6269 -- D1 in T1 D1 in R itself no
6270 -- D2 in T1 D2 in R itself no
6271 -- D3 in T1 D3 in R itself no
6273 -- X1 in T2 D3 in T1 D3 in T2 no
6274 -- X2 in T2 D1 in T1 D1 in T2 no
6275 -- D1 in T2 empty itself yes
6276 -- D2 in T2 empty itself yes
6277 -- D3 in T2 empty itself yes
6279 -- X1 in T3 X1 in T2 D3 in T3 no
6280 -- X2 in T3 X2 in T2 D1 in T3 no
6281 -- D1 in T3 empty itself yes
6282 -- D2 in T3 empty itself yes
6283 -- D3 in T3 empty itself yes
6285 -- Y in T4 X1 in T3 D3 in T3 no
6286 -- D1 in T3 empty itself yes
6287 -- D2 in T3 empty itself yes
6288 -- D3 in T3 empty itself yes
6290 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES
6292 -- Type derivation for tagged types is fairly straightforward. If no
6293 -- discriminants are specified by the derived type, these are inherited
6294 -- from the parent. No explicit stored discriminants are ever necessary.
6295 -- The only manipulation that is done to the tree is that of adding a
6296 -- _parent field with parent type and constrained to the same constraint
6297 -- specified for the parent in the derived type definition. For instance:
6299 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
6300 -- type T1 is new R with null record;
6301 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
6303 -- are changed into:
6305 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
6306 -- _parent : R (D1, D2, D3);
6309 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
6310 -- _parent : T1 (X2, 88, X1);
6313 -- The discriminants actually present in R, T1 and T2 as well as their CD,
6314 -- ORC and ICH fields are:
6316 -- Discrim CD ORC ICH
6317 -- ^^^^^^^ ^^ ^^^ ^^^
6318 -- D1 in R empty itself no
6319 -- D2 in R empty itself no
6320 -- D3 in R empty itself no
6322 -- D1 in T1 D1 in R D1 in R no
6323 -- D2 in T1 D2 in R D2 in R no
6324 -- D3 in T1 D3 in R D3 in R no
6326 -- X1 in T2 D3 in T1 D3 in R no
6327 -- X2 in T2 D1 in T1 D1 in R no
6329 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS
6331 -- Regardless of whether we dealing with a tagged or untagged type
6332 -- we will transform all derived type declarations of the form
6334 -- type T is new R (...) [with ...];
6336 -- subtype S is R (...);
6337 -- type T is new S [with ...];
6339 -- type BT is new R [with ...];
6340 -- subtype T is BT (...);
6342 -- That is, the base derived type is constrained only if it has no
6343 -- discriminants. The reason for doing this is that GNAT's semantic model
6344 -- assumes that a base type with discriminants is unconstrained.
6346 -- Note that, strictly speaking, the above transformation is not always
6347 -- correct. Consider for instance the following excerpt from ACVC b34011a:
6349 -- procedure B34011A is
6350 -- type REC (D : integer := 0) is record
6355 -- type T6 is new Rec;
6356 -- function F return T6;
6361 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
6364 -- The definition of Q6.U is illegal. However transforming Q6.U into
6366 -- type BaseU is new T6;
6367 -- subtype U is BaseU (Q6.F.I)
6369 -- turns U into a legal subtype, which is incorrect. To avoid this problem
6370 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
6371 -- the transformation described above.
6373 -- There is another instance where the above transformation is incorrect.
6377 -- type Base (D : Integer) is tagged null record;
6378 -- procedure P (X : Base);
6380 -- type Der is new Base (2) with null record;
6381 -- procedure P (X : Der);
6384 -- Then the above transformation turns this into
6386 -- type Der_Base is new Base with null record;
6387 -- -- procedure P (X : Base) is implicitly inherited here
6388 -- -- as procedure P (X : Der_Base).
6390 -- subtype Der is Der_Base (2);
6391 -- procedure P (X : Der);
6392 -- -- The overriding of P (X : Der_Base) is illegal since we
6393 -- -- have a parameter conformance problem.
6395 -- To get around this problem, after having semantically processed Der_Base
6396 -- and the rewritten subtype declaration for Der, we copy Der_Base field
6397 -- Discriminant_Constraint from Der so that when parameter conformance is
6398 -- checked when P is overridden, no semantic errors are flagged.
6400 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS
6402 -- Regardless of whether we are dealing with a tagged or untagged type
6403 -- we will transform all derived type declarations of the form
6405 -- type R (D1, .., Dn : ...) is [tagged] record ...;
6406 -- type T is new R [with ...];
6408 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
6410 -- The reason for such transformation is that it allows us to implement a
6411 -- very clean form of component inheritance as explained below.
6413 -- Note that this transformation is not achieved by direct tree rewriting
6414 -- and manipulation, but rather by redoing the semantic actions that the
6415 -- above transformation will entail. This is done directly in routine
6416 -- Inherit_Components.
6418 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE
6420 -- In both tagged and untagged derived types, regular non discriminant
6421 -- components are inherited in the derived type from the parent type. In
6422 -- the absence of discriminants component, inheritance is straightforward
6423 -- as components can simply be copied from the parent.
6425 -- If the parent has discriminants, inheriting components constrained with
6426 -- these discriminants requires caution. Consider the following example:
6428 -- type R (D1, D2 : Positive) is [tagged] record
6429 -- S : String (D1 .. D2);
6432 -- type T1 is new R [with null record];
6433 -- type T2 (X : positive) is new R (1, X) [with null record];
6435 -- As explained in 6. above, T1 is rewritten as
6436 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
6437 -- which makes the treatment for T1 and T2 identical.
6439 -- What we want when inheriting S, is that references to D1 and D2 in R are
6440 -- replaced with references to their correct constraints, i.e. D1 and D2 in
6441 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
6442 -- with either discriminant references in the derived type or expressions.
6443 -- This replacement is achieved as follows: before inheriting R's
6444 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
6445 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
6446 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
6447 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
6448 -- by String (1 .. X).
6450 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS
6452 -- We explain here the rules governing private type extensions relevant to
6453 -- type derivation. These rules are explained on the following example:
6455 -- type D [(...)] is new A [(...)] with private; <-- partial view
6456 -- type D [(...)] is new P [(...)] with null record; <-- full view
6458 -- Type A is called the ancestor subtype of the private extension.
6459 -- Type P is the parent type of the full view of the private extension. It
6460 -- must be A or a type derived from A.
6462 -- The rules concerning the discriminants of private type extensions are
6465 -- o If a private extension inherits known discriminants from the ancestor
6466 -- subtype, then the full view shall also inherit its discriminants from
6467 -- the ancestor subtype and the parent subtype of the full view shall be
6468 -- constrained if and only if the ancestor subtype is constrained.
6470 -- o If a partial view has unknown discriminants, then the full view may
6471 -- define a definite or an indefinite subtype, with or without
6474 -- o If a partial view has neither known nor unknown discriminants, then
6475 -- the full view shall define a definite subtype.
6477 -- o If the ancestor subtype of a private extension has constrained
6478 -- discriminants, then the parent subtype of the full view shall impose a
6479 -- statically matching constraint on those discriminants.
6481 -- This means that only the following forms of private extensions are
6484 -- type D is new A with private; <-- partial view
6485 -- type D is new P with null record; <-- full view
6487 -- If A has no discriminants than P has no discriminants, otherwise P must
6488 -- inherit A's discriminants.
6490 -- type D is new A (...) with private; <-- partial view
6491 -- type D is new P (:::) with null record; <-- full view
6493 -- P must inherit A's discriminants and (...) and (:::) must statically
6496 -- subtype A is R (...);
6497 -- type D is new A with private; <-- partial view
6498 -- type D is new P with null record; <-- full view
6500 -- P must have inherited R's discriminants and must be derived from A or
6501 -- any of its subtypes.
6503 -- type D (..) is new A with private; <-- partial view
6504 -- type D (..) is new P [(:::)] with null record; <-- full view
6506 -- No specific constraints on P's discriminants or constraint (:::).
6507 -- Note that A can be unconstrained, but the parent subtype P must either
6508 -- be constrained or (:::) must be present.
6510 -- type D (..) is new A [(...)] with private; <-- partial view
6511 -- type D (..) is new P [(:::)] with null record; <-- full view
6513 -- P's constraints on A's discriminants must statically match those
6514 -- imposed by (...).
6516 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS
6518 -- The full view of a private extension is handled exactly as described
6519 -- above. The model chose for the private view of a private extension is
6520 -- the same for what concerns discriminants (i.e. they receive the same
6521 -- treatment as in the tagged case). However, the private view of the
6522 -- private extension always inherits the components of the parent base,
6523 -- without replacing any discriminant reference. Strictly speaking this is
6524 -- incorrect. However, Gigi never uses this view to generate code so this
6525 -- is a purely semantic issue. In theory, a set of transformations similar
6526 -- to those given in 5. and 6. above could be applied to private views of
6527 -- private extensions to have the same model of component inheritance as
6528 -- for non private extensions. However, this is not done because it would
6529 -- further complicate private type processing. Semantically speaking, this
6530 -- leaves us in an uncomfortable situation. As an example consider:
6533 -- type R (D : integer) is tagged record
6534 -- S : String (1 .. D);
6536 -- procedure P (X : R);
6537 -- type T is new R (1) with private;
6539 -- type T is new R (1) with null record;
6542 -- This is transformed into:
6545 -- type R (D : integer) is tagged record
6546 -- S : String (1 .. D);
6548 -- procedure P (X : R);
6549 -- type T is new R (1) with private;
6551 -- type BaseT is new R with null record;
6552 -- subtype T is BaseT (1);
6555 -- (strictly speaking the above is incorrect Ada)
6557 -- From the semantic standpoint the private view of private extension T
6558 -- should be flagged as constrained since one can clearly have
6562 -- in a unit withing Pack. However, when deriving subprograms for the
6563 -- private view of private extension T, T must be seen as unconstrained
6564 -- since T has discriminants (this is a constraint of the current
6565 -- subprogram derivation model). Thus, when processing the private view of
6566 -- a private extension such as T, we first mark T as unconstrained, we
6567 -- process it, we perform program derivation and just before returning from
6568 -- Build_Derived_Record_Type we mark T as constrained.
6570 -- ??? Are there are other uncomfortable cases that we will have to
6573 -- 10. RECORD_TYPE_WITH_PRIVATE complications
6575 -- Types that are derived from a visible record type and have a private
6576 -- extension present other peculiarities. They behave mostly like private
6577 -- types, but if they have primitive operations defined, these will not
6578 -- have the proper signatures for further inheritance, because other
6579 -- primitive operations will use the implicit base that we define for
6580 -- private derivations below. This affect subprogram inheritance (see
6581 -- Derive_Subprograms for details). We also derive the implicit base from
6582 -- the base type of the full view, so that the implicit base is a record
6583 -- type and not another private type, This avoids infinite loops.
6585 procedure Build_Derived_Record_Type
6587 Parent_Type : Entity_Id;
6588 Derived_Type : Entity_Id;
6589 Derive_Subps : Boolean := True)
6591 Loc : constant Source_Ptr := Sloc (N);
6592 Parent_Base : Entity_Id;
6595 Discrim : Entity_Id;
6596 Last_Discrim : Entity_Id;
6599 Discs : Elist_Id := New_Elmt_List;
6600 -- An empty Discs list means that there were no constraints in the
6601 -- subtype indication or that there was an error processing it.
6603 Assoc_List : Elist_Id;
6604 New_Discrs : Elist_Id;
6605 New_Base : Entity_Id;
6607 New_Indic : Node_Id;
6609 Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type);
6610 Discriminant_Specs : constant Boolean :=
6611 Present (Discriminant_Specifications (N));
6612 Private_Extension : constant Boolean :=
6613 Nkind (N) = N_Private_Extension_Declaration;
6615 Constraint_Present : Boolean;
6616 Inherit_Discrims : Boolean := False;
6617 Save_Etype : Entity_Id;
6618 Save_Discr_Constr : Elist_Id;
6619 Save_Next_Entity : Entity_Id;
6622 if Ekind (Parent_Type) = E_Record_Type_With_Private
6623 and then Present (Full_View (Parent_Type))
6624 and then Has_Discriminants (Parent_Type)
6626 Parent_Base := Base_Type (Full_View (Parent_Type));
6628 Parent_Base := Base_Type (Parent_Type);
6631 -- Before we start the previously documented transformations, here is
6632 -- little fix for size and alignment of tagged types. Normally when we
6633 -- derive type D from type P, we copy the size and alignment of P as the
6634 -- default for D, and in the absence of explicit representation clauses
6635 -- for D, the size and alignment are indeed the same as the parent.
6637 -- But this is wrong for tagged types, since fields may be added, and
6638 -- the default size may need to be larger, and the default alignment may
6639 -- need to be larger.
6641 -- We therefore reset the size and alignment fields in the tagged case.
6642 -- Note that the size and alignment will in any case be at least as
6643 -- large as the parent type (since the derived type has a copy of the
6644 -- parent type in the _parent field)
6646 -- The type is also marked as being tagged here, which is needed when
6647 -- processing components with a self-referential anonymous access type
6648 -- in the call to Check_Anonymous_Access_Components below. Note that
6649 -- this flag is also set later on for completeness.
6652 Set_Is_Tagged_Type (Derived_Type);
6653 Init_Size_Align (Derived_Type);
6656 -- STEP 0a: figure out what kind of derived type declaration we have
6658 if Private_Extension then
6660 Set_Ekind (Derived_Type, E_Record_Type_With_Private);
6663 Type_Def := Type_Definition (N);
6665 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
6666 -- Parent_Base can be a private type or private extension. However,
6667 -- for tagged types with an extension the newly added fields are
6668 -- visible and hence the Derived_Type is always an E_Record_Type.
6669 -- (except that the parent may have its own private fields).
6670 -- For untagged types we preserve the Ekind of the Parent_Base.
6672 if Present (Record_Extension_Part (Type_Def)) then
6673 Set_Ekind (Derived_Type, E_Record_Type);
6675 -- Create internal access types for components with anonymous
6678 if Ada_Version >= Ada_05 then
6679 Check_Anonymous_Access_Components
6680 (N, Derived_Type, Derived_Type,
6681 Component_List (Record_Extension_Part (Type_Def)));
6685 Set_Ekind (Derived_Type, Ekind (Parent_Base));
6689 -- Indic can either be an N_Identifier if the subtype indication
6690 -- contains no constraint or an N_Subtype_Indication if the subtype
6691 -- indication has a constraint.
6693 Indic := Subtype_Indication (Type_Def);
6694 Constraint_Present := (Nkind (Indic) = N_Subtype_Indication);
6696 -- Check that the type has visible discriminants. The type may be
6697 -- a private type with unknown discriminants whose full view has
6698 -- discriminants which are invisible.
6700 if Constraint_Present then
6701 if not Has_Discriminants (Parent_Base)
6703 (Has_Unknown_Discriminants (Parent_Base)
6704 and then Is_Private_Type (Parent_Base))
6707 ("invalid constraint: type has no discriminant",
6708 Constraint (Indic));
6710 Constraint_Present := False;
6711 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
6713 elsif Is_Constrained (Parent_Type) then
6715 ("invalid constraint: parent type is already constrained",
6716 Constraint (Indic));
6718 Constraint_Present := False;
6719 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
6723 -- STEP 0b: If needed, apply transformation given in point 5. above
6725 if not Private_Extension
6726 and then Has_Discriminants (Parent_Type)
6727 and then not Discriminant_Specs
6728 and then (Is_Constrained (Parent_Type) or else Constraint_Present)
6730 -- First, we must analyze the constraint (see comment in point 5.)
6732 if Constraint_Present then
6733 New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic);
6735 if Has_Discriminants (Derived_Type)
6736 and then Has_Private_Declaration (Derived_Type)
6737 and then Present (Discriminant_Constraint (Derived_Type))
6739 -- Verify that constraints of the full view statically match
6740 -- those given in the partial view.
6746 C1 := First_Elmt (New_Discrs);
6747 C2 := First_Elmt (Discriminant_Constraint (Derived_Type));
6748 while Present (C1) and then Present (C2) loop
6749 if Fully_Conformant_Expressions (Node (C1), Node (C2))
6751 (Is_OK_Static_Expression (Node (C1))
6753 Is_OK_Static_Expression (Node (C2))
6755 Expr_Value (Node (C1)) = Expr_Value (Node (C2)))
6761 "constraint not conformant to previous declaration",
6772 -- Insert and analyze the declaration for the unconstrained base type
6774 New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B');
6777 Make_Full_Type_Declaration (Loc,
6778 Defining_Identifier => New_Base,
6780 Make_Derived_Type_Definition (Loc,
6781 Abstract_Present => Abstract_Present (Type_Def),
6782 Limited_Present => Limited_Present (Type_Def),
6783 Subtype_Indication =>
6784 New_Occurrence_Of (Parent_Base, Loc),
6785 Record_Extension_Part =>
6786 Relocate_Node (Record_Extension_Part (Type_Def)),
6787 Interface_List => Interface_List (Type_Def)));
6789 Set_Parent (New_Decl, Parent (N));
6790 Mark_Rewrite_Insertion (New_Decl);
6791 Insert_Before (N, New_Decl);
6793 -- In the tagged case, make sure ancestor is frozen appropriately
6794 -- (see also non-discriminated case below).
6796 if not Private_Extension or else Is_Interface (Parent_Base) then
6797 Freeze_Before (New_Decl, Parent_Type);
6800 -- Note that this call passes False for the Derive_Subps parameter
6801 -- because subprogram derivation is deferred until after creating
6802 -- the subtype (see below).
6805 (New_Decl, Parent_Base, New_Base,
6806 Is_Completion => True, Derive_Subps => False);
6808 -- ??? This needs re-examination to determine whether the
6809 -- above call can simply be replaced by a call to Analyze.
6811 Set_Analyzed (New_Decl);
6813 -- Insert and analyze the declaration for the constrained subtype
6815 if Constraint_Present then
6817 Make_Subtype_Indication (Loc,
6818 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
6819 Constraint => Relocate_Node (Constraint (Indic)));
6823 Constr_List : constant List_Id := New_List;
6828 C := First_Elmt (Discriminant_Constraint (Parent_Type));
6829 while Present (C) loop
6832 -- It is safe here to call New_Copy_Tree since
6833 -- Force_Evaluation was called on each constraint in
6834 -- Build_Discriminant_Constraints.
6836 Append (New_Copy_Tree (Expr), To => Constr_List);
6842 Make_Subtype_Indication (Loc,
6843 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
6845 Make_Index_Or_Discriminant_Constraint (Loc, Constr_List));
6850 Make_Subtype_Declaration (Loc,
6851 Defining_Identifier => Derived_Type,
6852 Subtype_Indication => New_Indic));
6856 -- Derivation of subprograms must be delayed until the full subtype
6857 -- has been established to ensure proper overriding of subprograms
6858 -- inherited by full types. If the derivations occurred as part of
6859 -- the call to Build_Derived_Type above, then the check for type
6860 -- conformance would fail because earlier primitive subprograms
6861 -- could still refer to the full type prior the change to the new
6862 -- subtype and hence would not match the new base type created here.
6864 Derive_Subprograms (Parent_Type, Derived_Type);
6866 -- For tagged types the Discriminant_Constraint of the new base itype
6867 -- is inherited from the first subtype so that no subtype conformance
6868 -- problem arise when the first subtype overrides primitive
6869 -- operations inherited by the implicit base type.
6872 Set_Discriminant_Constraint
6873 (New_Base, Discriminant_Constraint (Derived_Type));
6879 -- If we get here Derived_Type will have no discriminants or it will be
6880 -- a discriminated unconstrained base type.
6882 -- STEP 1a: perform preliminary actions/checks for derived tagged types
6886 -- The parent type is frozen for non-private extensions (RM 13.14(7))
6887 -- The declaration of a specific descendant of an interface type
6888 -- freezes the interface type (RM 13.14).
6890 if not Private_Extension or else Is_Interface (Parent_Base) then
6891 Freeze_Before (N, Parent_Type);
6894 -- In Ada 2005 (AI-344), the restriction that a derived tagged type
6895 -- cannot be declared at a deeper level than its parent type is
6896 -- removed. The check on derivation within a generic body is also
6897 -- relaxed, but there's a restriction that a derived tagged type
6898 -- cannot be declared in a generic body if it's derived directly
6899 -- or indirectly from a formal type of that generic.
6901 if Ada_Version >= Ada_05 then
6902 if Present (Enclosing_Generic_Body (Derived_Type)) then
6904 Ancestor_Type : Entity_Id;
6907 -- Check to see if any ancestor of the derived type is a
6910 Ancestor_Type := Parent_Type;
6911 while not Is_Generic_Type (Ancestor_Type)
6912 and then Etype (Ancestor_Type) /= Ancestor_Type
6914 Ancestor_Type := Etype (Ancestor_Type);
6917 -- If the derived type does have a formal type as an
6918 -- ancestor, then it's an error if the derived type is
6919 -- declared within the body of the generic unit that
6920 -- declares the formal type in its generic formal part. It's
6921 -- sufficient to check whether the ancestor type is declared
6922 -- inside the same generic body as the derived type (such as
6923 -- within a nested generic spec), in which case the
6924 -- derivation is legal. If the formal type is declared
6925 -- outside of that generic body, then it's guaranteed that
6926 -- the derived type is declared within the generic body of
6927 -- the generic unit declaring the formal type.
6929 if Is_Generic_Type (Ancestor_Type)
6930 and then Enclosing_Generic_Body (Ancestor_Type) /=
6931 Enclosing_Generic_Body (Derived_Type)
6934 ("parent type of& must not be descendant of formal type"
6935 & " of an enclosing generic body",
6936 Indic, Derived_Type);
6941 elsif Type_Access_Level (Derived_Type) /=
6942 Type_Access_Level (Parent_Type)
6943 and then not Is_Generic_Type (Derived_Type)
6945 if Is_Controlled (Parent_Type) then
6947 ("controlled type must be declared at the library level",
6951 ("type extension at deeper accessibility level than parent",
6957 GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type);
6961 and then GB /= Enclosing_Generic_Body (Parent_Base)
6964 ("parent type of& must not be outside generic body"
6966 Indic, Derived_Type);
6972 -- Ada 2005 (AI-251)
6974 if Ada_Version >= Ada_05 and then Is_Tagged then
6976 -- "The declaration of a specific descendant of an interface type
6977 -- freezes the interface type" (RM 13.14).
6982 if Is_Non_Empty_List (Interface_List (Type_Def)) then
6983 Iface := First (Interface_List (Type_Def));
6984 while Present (Iface) loop
6985 Freeze_Before (N, Etype (Iface));
6992 -- STEP 1b : preliminary cleanup of the full view of private types
6994 -- If the type is already marked as having discriminants, then it's the
6995 -- completion of a private type or private extension and we need to
6996 -- retain the discriminants from the partial view if the current
6997 -- declaration has Discriminant_Specifications so that we can verify
6998 -- conformance. However, we must remove any existing components that
6999 -- were inherited from the parent (and attached in Copy_And_Swap)
7000 -- because the full type inherits all appropriate components anyway, and
7001 -- we do not want the partial view's components interfering.
7003 if Has_Discriminants (Derived_Type) and then Discriminant_Specs then
7004 Discrim := First_Discriminant (Derived_Type);
7006 Last_Discrim := Discrim;
7007 Next_Discriminant (Discrim);
7008 exit when No (Discrim);
7011 Set_Last_Entity (Derived_Type, Last_Discrim);
7013 -- In all other cases wipe out the list of inherited components (even
7014 -- inherited discriminants), it will be properly rebuilt here.
7017 Set_First_Entity (Derived_Type, Empty);
7018 Set_Last_Entity (Derived_Type, Empty);
7021 -- STEP 1c: Initialize some flags for the Derived_Type
7023 -- The following flags must be initialized here so that
7024 -- Process_Discriminants can check that discriminants of tagged types do
7025 -- not have a default initial value and that access discriminants are
7026 -- only specified for limited records. For completeness, these flags are
7027 -- also initialized along with all the other flags below.
7029 -- AI-419: Limitedness is not inherited from an interface parent, so to
7030 -- be limited in that case the type must be explicitly declared as
7031 -- limited. However, task and protected interfaces are always limited.
7033 if Limited_Present (Type_Def) then
7034 Set_Is_Limited_Record (Derived_Type);
7036 elsif Is_Limited_Record (Parent_Type)
7037 or else (Present (Full_View (Parent_Type))
7038 and then Is_Limited_Record (Full_View (Parent_Type)))
7040 if not Is_Interface (Parent_Type)
7041 or else Is_Synchronized_Interface (Parent_Type)
7042 or else Is_Protected_Interface (Parent_Type)
7043 or else Is_Task_Interface (Parent_Type)
7045 Set_Is_Limited_Record (Derived_Type);
7049 -- STEP 2a: process discriminants of derived type if any
7051 Push_Scope (Derived_Type);
7053 if Discriminant_Specs then
7054 Set_Has_Unknown_Discriminants (Derived_Type, False);
7056 -- The following call initializes fields Has_Discriminants and
7057 -- Discriminant_Constraint, unless we are processing the completion
7058 -- of a private type declaration.
7060 Check_Or_Process_Discriminants (N, Derived_Type);
7062 -- For non-tagged types the constraint on the Parent_Type must be
7063 -- present and is used to rename the discriminants.
7065 if not Is_Tagged and then not Has_Discriminants (Parent_Type) then
7066 Error_Msg_N ("untagged parent must have discriminants", Indic);
7068 elsif not Is_Tagged and then not Constraint_Present then
7070 ("discriminant constraint needed for derived untagged records",
7073 -- Otherwise the parent subtype must be constrained unless we have a
7074 -- private extension.
7076 elsif not Constraint_Present
7077 and then not Private_Extension
7078 and then not Is_Constrained (Parent_Type)
7081 ("unconstrained type not allowed in this context", Indic);
7083 elsif Constraint_Present then
7084 -- The following call sets the field Corresponding_Discriminant
7085 -- for the discriminants in the Derived_Type.
7087 Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True);
7089 -- For untagged types all new discriminants must rename
7090 -- discriminants in the parent. For private extensions new
7091 -- discriminants cannot rename old ones (implied by [7.3(13)]).
7093 Discrim := First_Discriminant (Derived_Type);
7094 while Present (Discrim) loop
7096 and then No (Corresponding_Discriminant (Discrim))
7099 ("new discriminants must constrain old ones", Discrim);
7101 elsif Private_Extension
7102 and then Present (Corresponding_Discriminant (Discrim))
7105 ("only static constraints allowed for parent"
7106 & " discriminants in the partial view", Indic);
7110 -- If a new discriminant is used in the constraint, then its
7111 -- subtype must be statically compatible with the parent
7112 -- discriminant's subtype (3.7(15)).
7114 if Present (Corresponding_Discriminant (Discrim))
7116 not Subtypes_Statically_Compatible
7118 Etype (Corresponding_Discriminant (Discrim)))
7121 ("subtype must be compatible with parent discriminant",
7125 Next_Discriminant (Discrim);
7128 -- Check whether the constraints of the full view statically
7129 -- match those imposed by the parent subtype [7.3(13)].
7131 if Present (Stored_Constraint (Derived_Type)) then
7136 C1 := First_Elmt (Discs);
7137 C2 := First_Elmt (Stored_Constraint (Derived_Type));
7138 while Present (C1) and then Present (C2) loop
7140 Fully_Conformant_Expressions (Node (C1), Node (C2))
7143 ("not conformant with previous declaration",
7154 -- STEP 2b: No new discriminants, inherit discriminants if any
7157 if Private_Extension then
7158 Set_Has_Unknown_Discriminants
7160 Has_Unknown_Discriminants (Parent_Type)
7161 or else Unknown_Discriminants_Present (N));
7163 -- The partial view of the parent may have unknown discriminants,
7164 -- but if the full view has discriminants and the parent type is
7165 -- in scope they must be inherited.
7167 elsif Has_Unknown_Discriminants (Parent_Type)
7169 (not Has_Discriminants (Parent_Type)
7170 or else not In_Open_Scopes (Scope (Parent_Type)))
7172 Set_Has_Unknown_Discriminants (Derived_Type);
7175 if not Has_Unknown_Discriminants (Derived_Type)
7176 and then not Has_Unknown_Discriminants (Parent_Base)
7177 and then Has_Discriminants (Parent_Type)
7179 Inherit_Discrims := True;
7180 Set_Has_Discriminants
7181 (Derived_Type, True);
7182 Set_Discriminant_Constraint
7183 (Derived_Type, Discriminant_Constraint (Parent_Base));
7186 -- The following test is true for private types (remember
7187 -- transformation 5. is not applied to those) and in an error
7190 if Constraint_Present then
7191 Discs := Build_Discriminant_Constraints (Parent_Type, Indic);
7194 -- For now mark a new derived type as constrained only if it has no
7195 -- discriminants. At the end of Build_Derived_Record_Type we properly
7196 -- set this flag in the case of private extensions. See comments in
7197 -- point 9. just before body of Build_Derived_Record_Type.
7201 not (Inherit_Discrims
7202 or else Has_Unknown_Discriminants (Derived_Type)));
7205 -- STEP 3: initialize fields of derived type
7207 Set_Is_Tagged_Type (Derived_Type, Is_Tagged);
7208 Set_Stored_Constraint (Derived_Type, No_Elist);
7210 -- Ada 2005 (AI-251): Private type-declarations can implement interfaces
7211 -- but cannot be interfaces
7213 if not Private_Extension
7214 and then Ekind (Derived_Type) /= E_Private_Type
7215 and then Ekind (Derived_Type) /= E_Limited_Private_Type
7217 if Interface_Present (Type_Def) then
7218 Analyze_Interface_Declaration (Derived_Type, Type_Def);
7221 Set_Interfaces (Derived_Type, No_Elist);
7224 -- Fields inherited from the Parent_Type
7227 (Derived_Type, Einfo.Discard_Names (Parent_Type));
7228 Set_Has_Specified_Layout
7229 (Derived_Type, Has_Specified_Layout (Parent_Type));
7230 Set_Is_Limited_Composite
7231 (Derived_Type, Is_Limited_Composite (Parent_Type));
7232 Set_Is_Private_Composite
7233 (Derived_Type, Is_Private_Composite (Parent_Type));
7235 -- Fields inherited from the Parent_Base
7237 Set_Has_Controlled_Component
7238 (Derived_Type, Has_Controlled_Component (Parent_Base));
7239 Set_Has_Non_Standard_Rep
7240 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
7241 Set_Has_Primitive_Operations
7242 (Derived_Type, Has_Primitive_Operations (Parent_Base));
7244 -- Fields inherited from the Parent_Base in the non-private case
7246 if Ekind (Derived_Type) = E_Record_Type then
7247 Set_Has_Complex_Representation
7248 (Derived_Type, Has_Complex_Representation (Parent_Base));
7251 -- Fields inherited from the Parent_Base for record types
7253 if Is_Record_Type (Derived_Type) then
7255 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
7256 -- Parent_Base can be a private type or private extension.
7258 if Present (Full_View (Parent_Base)) then
7259 Set_OK_To_Reorder_Components
7261 OK_To_Reorder_Components (Full_View (Parent_Base)));
7262 Set_Reverse_Bit_Order
7263 (Derived_Type, Reverse_Bit_Order (Full_View (Parent_Base)));
7265 Set_OK_To_Reorder_Components
7266 (Derived_Type, OK_To_Reorder_Components (Parent_Base));
7267 Set_Reverse_Bit_Order
7268 (Derived_Type, Reverse_Bit_Order (Parent_Base));
7272 -- Direct controlled types do not inherit Finalize_Storage_Only flag
7274 if not Is_Controlled (Parent_Type) then
7275 Set_Finalize_Storage_Only
7276 (Derived_Type, Finalize_Storage_Only (Parent_Type));
7279 -- Set fields for private derived types
7281 if Is_Private_Type (Derived_Type) then
7282 Set_Depends_On_Private (Derived_Type, True);
7283 Set_Private_Dependents (Derived_Type, New_Elmt_List);
7285 -- Inherit fields from non private record types. If this is the
7286 -- completion of a derivation from a private type, the parent itself
7287 -- is private, and the attributes come from its full view, which must
7291 if Is_Private_Type (Parent_Base)
7292 and then not Is_Record_Type (Parent_Base)
7294 Set_Component_Alignment
7295 (Derived_Type, Component_Alignment (Full_View (Parent_Base)));
7297 (Derived_Type, C_Pass_By_Copy (Full_View (Parent_Base)));
7299 Set_Component_Alignment
7300 (Derived_Type, Component_Alignment (Parent_Base));
7302 (Derived_Type, C_Pass_By_Copy (Parent_Base));
7306 -- Set fields for tagged types
7309 Set_Primitive_Operations (Derived_Type, New_Elmt_List);
7311 -- All tagged types defined in Ada.Finalization are controlled
7313 if Chars (Scope (Derived_Type)) = Name_Finalization
7314 and then Chars (Scope (Scope (Derived_Type))) = Name_Ada
7315 and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard
7317 Set_Is_Controlled (Derived_Type);
7319 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Base));
7322 -- Minor optimization: there is no need to generate the class-wide
7323 -- entity associated with an underlying record view.
7325 if not Is_Underlying_Record_View (Derived_Type) then
7326 Make_Class_Wide_Type (Derived_Type);
7329 Set_Is_Abstract_Type (Derived_Type, Abstract_Present (Type_Def));
7331 if Has_Discriminants (Derived_Type)
7332 and then Constraint_Present
7334 Set_Stored_Constraint
7335 (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs));
7338 if Ada_Version >= Ada_05 then
7340 Ifaces_List : Elist_Id;
7343 -- Checks rules 3.9.4 (13/2 and 14/2)
7345 if Comes_From_Source (Derived_Type)
7346 and then not Is_Private_Type (Derived_Type)
7347 and then Is_Interface (Parent_Type)
7348 and then not Is_Interface (Derived_Type)
7350 if Is_Task_Interface (Parent_Type) then
7352 ("(Ada 2005) task type required (RM 3.9.4 (13.2))",
7355 elsif Is_Protected_Interface (Parent_Type) then
7357 ("(Ada 2005) protected type required (RM 3.9.4 (14.2))",
7362 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
7364 Check_Interfaces (N, Type_Def);
7366 -- Ada 2005 (AI-251): Collect the list of progenitors that are
7367 -- not already in the parents.
7371 Ifaces_List => Ifaces_List,
7372 Exclude_Parents => True);
7374 Set_Interfaces (Derived_Type, Ifaces_List);
7376 -- If the derived type is the anonymous type created for
7377 -- a declaration whose parent has a constraint, propagate
7378 -- the interface list to the source type. This must be done
7379 -- prior to the completion of the analysis of the source type
7380 -- because the components in the extension may contain current
7381 -- instances whose legality depends on some ancestor.
7383 if Is_Itype (Derived_Type) then
7385 Def : constant Node_Id :=
7386 Associated_Node_For_Itype (Derived_Type);
7389 and then Nkind (Def) = N_Full_Type_Declaration
7392 (Defining_Identifier (Def), Ifaces_List);
7400 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Base));
7401 Set_Has_Non_Standard_Rep
7402 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
7405 -- STEP 4: Inherit components from the parent base and constrain them.
7406 -- Apply the second transformation described in point 6. above.
7408 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
7409 or else not Has_Discriminants (Parent_Type)
7410 or else not Is_Constrained (Parent_Type)
7414 Constrs := Discriminant_Constraint (Parent_Type);
7419 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
7421 -- STEP 5a: Copy the parent record declaration for untagged types
7423 if not Is_Tagged then
7425 -- Discriminant_Constraint (Derived_Type) has been properly
7426 -- constructed. Save it and temporarily set it to Empty because we
7427 -- do not want the call to New_Copy_Tree below to mess this list.
7429 if Has_Discriminants (Derived_Type) then
7430 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
7431 Set_Discriminant_Constraint (Derived_Type, No_Elist);
7433 Save_Discr_Constr := No_Elist;
7436 -- Save the Etype field of Derived_Type. It is correctly set now,
7437 -- but the call to New_Copy tree may remap it to point to itself,
7438 -- which is not what we want. Ditto for the Next_Entity field.
7440 Save_Etype := Etype (Derived_Type);
7441 Save_Next_Entity := Next_Entity (Derived_Type);
7443 -- Assoc_List maps all stored discriminants in the Parent_Base to
7444 -- stored discriminants in the Derived_Type. It is fundamental that
7445 -- no types or itypes with discriminants other than the stored
7446 -- discriminants appear in the entities declared inside
7447 -- Derived_Type, since the back end cannot deal with it.
7451 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
7453 -- Restore the fields saved prior to the New_Copy_Tree call
7454 -- and compute the stored constraint.
7456 Set_Etype (Derived_Type, Save_Etype);
7457 Set_Next_Entity (Derived_Type, Save_Next_Entity);
7459 if Has_Discriminants (Derived_Type) then
7460 Set_Discriminant_Constraint
7461 (Derived_Type, Save_Discr_Constr);
7462 Set_Stored_Constraint
7463 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
7464 Replace_Components (Derived_Type, New_Decl);
7467 -- Insert the new derived type declaration
7469 Rewrite (N, New_Decl);
7471 -- STEP 5b: Complete the processing for record extensions in generics
7473 -- There is no completion for record extensions declared in the
7474 -- parameter part of a generic, so we need to complete processing for
7475 -- these generic record extensions here. The Record_Type_Definition call
7476 -- will change the Ekind of the components from E_Void to E_Component.
7478 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
7479 Record_Type_Definition (Empty, Derived_Type);
7481 -- STEP 5c: Process the record extension for non private tagged types
7483 elsif not Private_Extension then
7485 -- Add the _parent field in the derived type
7487 Expand_Record_Extension (Derived_Type, Type_Def);
7489 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
7490 -- implemented interfaces if we are in expansion mode
7493 and then Has_Interfaces (Derived_Type)
7495 Add_Interface_Tag_Components (N, Derived_Type);
7498 -- Analyze the record extension
7500 Record_Type_Definition
7501 (Record_Extension_Part (Type_Def), Derived_Type);
7506 -- Nothing else to do if there is an error in the derivation.
7507 -- An unusual case: the full view may be derived from a type in an
7508 -- instance, when the partial view was used illegally as an actual
7509 -- in that instance, leading to a circular definition.
7511 if Etype (Derived_Type) = Any_Type
7512 or else Etype (Parent_Type) = Derived_Type
7517 -- Set delayed freeze and then derive subprograms, we need to do
7518 -- this in this order so that derived subprograms inherit the
7519 -- derived freeze if necessary.
7521 Set_Has_Delayed_Freeze (Derived_Type);
7523 if Derive_Subps then
7524 Derive_Subprograms (Parent_Type, Derived_Type);
7527 -- If we have a private extension which defines a constrained derived
7528 -- type mark as constrained here after we have derived subprograms. See
7529 -- comment on point 9. just above the body of Build_Derived_Record_Type.
7531 if Private_Extension and then Inherit_Discrims then
7532 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
7533 Set_Is_Constrained (Derived_Type, True);
7534 Set_Discriminant_Constraint (Derived_Type, Discs);
7536 elsif Is_Constrained (Parent_Type) then
7538 (Derived_Type, True);
7539 Set_Discriminant_Constraint
7540 (Derived_Type, Discriminant_Constraint (Parent_Type));
7544 -- Update the class-wide type, which shares the now-completed entity
7545 -- list with its specific type. In case of underlying record views,
7546 -- we do not generate the corresponding class wide entity.
7549 and then not Is_Underlying_Record_View (Derived_Type)
7552 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
7554 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
7557 -- Update the scope of anonymous access types of discriminants and other
7558 -- components, to prevent scope anomalies in gigi, when the derivation
7559 -- appears in a scope nested within that of the parent.
7565 D := First_Entity (Derived_Type);
7566 while Present (D) loop
7567 if Ekind_In (D, E_Discriminant, E_Component) then
7568 if Is_Itype (Etype (D))
7569 and then Ekind (Etype (D)) = E_Anonymous_Access_Type
7571 Set_Scope (Etype (D), Current_Scope);
7578 end Build_Derived_Record_Type;
7580 ------------------------
7581 -- Build_Derived_Type --
7582 ------------------------
7584 procedure Build_Derived_Type
7586 Parent_Type : Entity_Id;
7587 Derived_Type : Entity_Id;
7588 Is_Completion : Boolean;
7589 Derive_Subps : Boolean := True)
7591 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
7594 -- Set common attributes
7596 Set_Scope (Derived_Type, Current_Scope);
7598 Set_Ekind (Derived_Type, Ekind (Parent_Base));
7599 Set_Etype (Derived_Type, Parent_Base);
7600 Set_Has_Task (Derived_Type, Has_Task (Parent_Base));
7602 Set_Size_Info (Derived_Type, Parent_Type);
7603 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
7604 Set_Convention (Derived_Type, Convention (Parent_Type));
7605 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
7606 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
7608 -- The derived type inherits the representation clauses of the parent.
7609 -- However, for a private type that is completed by a derivation, there
7610 -- may be operation attributes that have been specified already (stream
7611 -- attributes and External_Tag) and those must be provided. Finally,
7612 -- if the partial view is a private extension, the representation items
7613 -- of the parent have been inherited already, and should not be chained
7614 -- twice to the derived type.
7616 if Is_Tagged_Type (Parent_Type)
7617 and then Present (First_Rep_Item (Derived_Type))
7619 -- The existing items are either operational items or items inherited
7620 -- from a private extension declaration.
7624 -- Used to iterate over representation items of the derived type
7627 -- Last representation item of the (non-empty) representation
7628 -- item list of the derived type.
7630 Found : Boolean := False;
7633 Rep := First_Rep_Item (Derived_Type);
7635 while Present (Rep) loop
7636 if Rep = First_Rep_Item (Parent_Type) then
7641 Rep := Next_Rep_Item (Rep);
7643 if Present (Rep) then
7649 -- Here if we either encountered the parent type's first rep
7650 -- item on the derived type's rep item list (in which case
7651 -- Found is True, and we have nothing else to do), or if we
7652 -- reached the last rep item of the derived type, which is
7653 -- Last_Rep, in which case we further chain the parent type's
7654 -- rep items to those of the derived type.
7657 Set_Next_Rep_Item (Last_Rep, First_Rep_Item (Parent_Type));
7662 Set_First_Rep_Item (Derived_Type, First_Rep_Item (Parent_Type));
7665 case Ekind (Parent_Type) is
7666 when Numeric_Kind =>
7667 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
7670 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
7674 | Class_Wide_Kind =>
7675 Build_Derived_Record_Type
7676 (N, Parent_Type, Derived_Type, Derive_Subps);
7679 when Enumeration_Kind =>
7680 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
7683 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
7685 when Incomplete_Or_Private_Kind =>
7686 Build_Derived_Private_Type
7687 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
7689 -- For discriminated types, the derivation includes deriving
7690 -- primitive operations. For others it is done below.
7692 if Is_Tagged_Type (Parent_Type)
7693 or else Has_Discriminants (Parent_Type)
7694 or else (Present (Full_View (Parent_Type))
7695 and then Has_Discriminants (Full_View (Parent_Type)))
7700 when Concurrent_Kind =>
7701 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
7704 raise Program_Error;
7707 if Etype (Derived_Type) = Any_Type then
7711 -- Set delayed freeze and then derive subprograms, we need to do this
7712 -- in this order so that derived subprograms inherit the derived freeze
7715 Set_Has_Delayed_Freeze (Derived_Type);
7716 if Derive_Subps then
7717 Derive_Subprograms (Parent_Type, Derived_Type);
7720 Set_Has_Primitive_Operations
7721 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
7722 end Build_Derived_Type;
7724 -----------------------
7725 -- Build_Discriminal --
7726 -----------------------
7728 procedure Build_Discriminal (Discrim : Entity_Id) is
7729 D_Minal : Entity_Id;
7730 CR_Disc : Entity_Id;
7733 -- A discriminal has the same name as the discriminant
7736 Make_Defining_Identifier (Sloc (Discrim),
7737 Chars => Chars (Discrim));
7739 Set_Ekind (D_Minal, E_In_Parameter);
7740 Set_Mechanism (D_Minal, Default_Mechanism);
7741 Set_Etype (D_Minal, Etype (Discrim));
7742 Set_Scope (D_Minal, Current_Scope);
7744 Set_Discriminal (Discrim, D_Minal);
7745 Set_Discriminal_Link (D_Minal, Discrim);
7747 -- For task types, build at once the discriminants of the corresponding
7748 -- record, which are needed if discriminants are used in entry defaults
7749 -- and in family bounds.
7751 if Is_Concurrent_Type (Current_Scope)
7752 or else Is_Limited_Type (Current_Scope)
7754 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
7756 Set_Ekind (CR_Disc, E_In_Parameter);
7757 Set_Mechanism (CR_Disc, Default_Mechanism);
7758 Set_Etype (CR_Disc, Etype (Discrim));
7759 Set_Scope (CR_Disc, Current_Scope);
7760 Set_Discriminal_Link (CR_Disc, Discrim);
7761 Set_CR_Discriminant (Discrim, CR_Disc);
7763 end Build_Discriminal;
7765 ------------------------------------
7766 -- Build_Discriminant_Constraints --
7767 ------------------------------------
7769 function Build_Discriminant_Constraints
7772 Derived_Def : Boolean := False) return Elist_Id
7774 C : constant Node_Id := Constraint (Def);
7775 Nb_Discr : constant Nat := Number_Discriminants (T);
7777 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
7778 -- Saves the expression corresponding to a given discriminant in T
7780 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
7781 -- Return the Position number within array Discr_Expr of a discriminant
7782 -- D within the discriminant list of the discriminated type T.
7788 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
7792 Disc := First_Discriminant (T);
7793 for J in Discr_Expr'Range loop
7798 Next_Discriminant (Disc);
7801 -- Note: Since this function is called on discriminants that are
7802 -- known to belong to the discriminated type, falling through the
7803 -- loop with no match signals an internal compiler error.
7805 raise Program_Error;
7808 -- Declarations local to Build_Discriminant_Constraints
7812 Elist : constant Elist_Id := New_Elmt_List;
7820 Discrim_Present : Boolean := False;
7822 -- Start of processing for Build_Discriminant_Constraints
7825 -- The following loop will process positional associations only.
7826 -- For a positional association, the (single) discriminant is
7827 -- implicitly specified by position, in textual order (RM 3.7.2).
7829 Discr := First_Discriminant (T);
7830 Constr := First (Constraints (C));
7831 for D in Discr_Expr'Range loop
7832 exit when Nkind (Constr) = N_Discriminant_Association;
7835 Error_Msg_N ("too few discriminants given in constraint", C);
7836 return New_Elmt_List;
7838 elsif Nkind (Constr) = N_Range
7839 or else (Nkind (Constr) = N_Attribute_Reference
7841 Attribute_Name (Constr) = Name_Range)
7844 ("a range is not a valid discriminant constraint", Constr);
7845 Discr_Expr (D) := Error;
7848 Analyze_And_Resolve (Constr, Base_Type (Etype (Discr)));
7849 Discr_Expr (D) := Constr;
7852 Next_Discriminant (Discr);
7856 if No (Discr) and then Present (Constr) then
7857 Error_Msg_N ("too many discriminants given in constraint", Constr);
7858 return New_Elmt_List;
7861 -- Named associations can be given in any order, but if both positional
7862 -- and named associations are used in the same discriminant constraint,
7863 -- then positional associations must occur first, at their normal
7864 -- position. Hence once a named association is used, the rest of the
7865 -- discriminant constraint must use only named associations.
7867 while Present (Constr) loop
7869 -- Positional association forbidden after a named association
7871 if Nkind (Constr) /= N_Discriminant_Association then
7872 Error_Msg_N ("positional association follows named one", Constr);
7873 return New_Elmt_List;
7875 -- Otherwise it is a named association
7878 -- E records the type of the discriminants in the named
7879 -- association. All the discriminants specified in the same name
7880 -- association must have the same type.
7884 -- Search the list of discriminants in T to see if the simple name
7885 -- given in the constraint matches any of them.
7887 Id := First (Selector_Names (Constr));
7888 while Present (Id) loop
7891 -- If Original_Discriminant is present, we are processing a
7892 -- generic instantiation and this is an instance node. We need
7893 -- to find the name of the corresponding discriminant in the
7894 -- actual record type T and not the name of the discriminant in
7895 -- the generic formal. Example:
7898 -- type G (D : int) is private;
7900 -- subtype W is G (D => 1);
7902 -- type Rec (X : int) is record ... end record;
7903 -- package Q is new P (G => Rec);
7905 -- At the point of the instantiation, formal type G is Rec
7906 -- and therefore when reanalyzing "subtype W is G (D => 1);"
7907 -- which really looks like "subtype W is Rec (D => 1);" at
7908 -- the point of instantiation, we want to find the discriminant
7909 -- that corresponds to D in Rec, i.e. X.
7911 if Present (Original_Discriminant (Id)) then
7912 Discr := Find_Corresponding_Discriminant (Id, T);
7916 Discr := First_Discriminant (T);
7917 while Present (Discr) loop
7918 if Chars (Discr) = Chars (Id) then
7923 Next_Discriminant (Discr);
7927 Error_Msg_N ("& does not match any discriminant", Id);
7928 return New_Elmt_List;
7930 -- The following is only useful for the benefit of generic
7931 -- instances but it does not interfere with other
7932 -- processing for the non-generic case so we do it in all
7933 -- cases (for generics this statement is executed when
7934 -- processing the generic definition, see comment at the
7935 -- beginning of this if statement).
7938 Set_Original_Discriminant (Id, Discr);
7942 Position := Pos_Of_Discr (T, Discr);
7944 if Present (Discr_Expr (Position)) then
7945 Error_Msg_N ("duplicate constraint for discriminant&", Id);
7948 -- Each discriminant specified in the same named association
7949 -- must be associated with a separate copy of the
7950 -- corresponding expression.
7952 if Present (Next (Id)) then
7953 Expr := New_Copy_Tree (Expression (Constr));
7954 Set_Parent (Expr, Parent (Expression (Constr)));
7956 Expr := Expression (Constr);
7959 Discr_Expr (Position) := Expr;
7960 Analyze_And_Resolve (Expr, Base_Type (Etype (Discr)));
7963 -- A discriminant association with more than one discriminant
7964 -- name is only allowed if the named discriminants are all of
7965 -- the same type (RM 3.7.1(8)).
7968 E := Base_Type (Etype (Discr));
7970 elsif Base_Type (Etype (Discr)) /= E then
7972 ("all discriminants in an association " &
7973 "must have the same type", Id);
7983 -- A discriminant constraint must provide exactly one value for each
7984 -- discriminant of the type (RM 3.7.1(8)).
7986 for J in Discr_Expr'Range loop
7987 if No (Discr_Expr (J)) then
7988 Error_Msg_N ("too few discriminants given in constraint", C);
7989 return New_Elmt_List;
7993 -- Determine if there are discriminant expressions in the constraint
7995 for J in Discr_Expr'Range loop
7996 if Denotes_Discriminant
7997 (Discr_Expr (J), Check_Concurrent => True)
7999 Discrim_Present := True;
8003 -- Build an element list consisting of the expressions given in the
8004 -- discriminant constraint and apply the appropriate checks. The list
8005 -- is constructed after resolving any named discriminant associations
8006 -- and therefore the expressions appear in the textual order of the
8009 Discr := First_Discriminant (T);
8010 for J in Discr_Expr'Range loop
8011 if Discr_Expr (J) /= Error then
8012 Append_Elmt (Discr_Expr (J), Elist);
8014 -- If any of the discriminant constraints is given by a
8015 -- discriminant and we are in a derived type declaration we
8016 -- have a discriminant renaming. Establish link between new
8017 -- and old discriminant.
8019 if Denotes_Discriminant (Discr_Expr (J)) then
8021 Set_Corresponding_Discriminant
8022 (Entity (Discr_Expr (J)), Discr);
8025 -- Force the evaluation of non-discriminant expressions.
8026 -- If we have found a discriminant in the constraint 3.4(26)
8027 -- and 3.8(18) demand that no range checks are performed are
8028 -- after evaluation. If the constraint is for a component
8029 -- definition that has a per-object constraint, expressions are
8030 -- evaluated but not checked either. In all other cases perform
8034 if Discrim_Present then
8037 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
8039 Has_Per_Object_Constraint
8040 (Defining_Identifier (Parent (Parent (Def))))
8044 elsif Is_Access_Type (Etype (Discr)) then
8045 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
8048 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
8051 Force_Evaluation (Discr_Expr (J));
8054 -- Check that the designated type of an access discriminant's
8055 -- expression is not a class-wide type unless the discriminant's
8056 -- designated type is also class-wide.
8058 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
8059 and then not Is_Class_Wide_Type
8060 (Designated_Type (Etype (Discr)))
8061 and then Etype (Discr_Expr (J)) /= Any_Type
8062 and then Is_Class_Wide_Type
8063 (Designated_Type (Etype (Discr_Expr (J))))
8065 Wrong_Type (Discr_Expr (J), Etype (Discr));
8067 elsif Is_Access_Type (Etype (Discr))
8068 and then not Is_Access_Constant (Etype (Discr))
8069 and then Is_Access_Type (Etype (Discr_Expr (J)))
8070 and then Is_Access_Constant (Etype (Discr_Expr (J)))
8073 ("constraint for discriminant& must be access to variable",
8078 Next_Discriminant (Discr);
8082 end Build_Discriminant_Constraints;
8084 ---------------------------------
8085 -- Build_Discriminated_Subtype --
8086 ---------------------------------
8088 procedure Build_Discriminated_Subtype
8092 Related_Nod : Node_Id;
8093 For_Access : Boolean := False)
8095 Has_Discrs : constant Boolean := Has_Discriminants (T);
8096 Constrained : constant Boolean :=
8098 and then not Is_Empty_Elmt_List (Elist)
8099 and then not Is_Class_Wide_Type (T))
8100 or else Is_Constrained (T);
8103 if Ekind (T) = E_Record_Type then
8105 Set_Ekind (Def_Id, E_Private_Subtype);
8106 Set_Is_For_Access_Subtype (Def_Id, True);
8108 Set_Ekind (Def_Id, E_Record_Subtype);
8111 -- Inherit preelaboration flag from base, for types for which it
8112 -- may have been set: records, private types, protected types.
8114 Set_Known_To_Have_Preelab_Init
8115 (Def_Id, Known_To_Have_Preelab_Init (T));
8117 elsif Ekind (T) = E_Task_Type then
8118 Set_Ekind (Def_Id, E_Task_Subtype);
8120 elsif Ekind (T) = E_Protected_Type then
8121 Set_Ekind (Def_Id, E_Protected_Subtype);
8122 Set_Known_To_Have_Preelab_Init
8123 (Def_Id, Known_To_Have_Preelab_Init (T));
8125 elsif Is_Private_Type (T) then
8126 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
8127 Set_Known_To_Have_Preelab_Init
8128 (Def_Id, Known_To_Have_Preelab_Init (T));
8130 elsif Is_Class_Wide_Type (T) then
8131 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
8134 -- Incomplete type. Attach subtype to list of dependents, to be
8135 -- completed with full view of parent type, unless is it the
8136 -- designated subtype of a record component within an init_proc.
8137 -- This last case arises for a component of an access type whose
8138 -- designated type is incomplete (e.g. a Taft Amendment type).
8139 -- The designated subtype is within an inner scope, and needs no
8140 -- elaboration, because only the access type is needed in the
8141 -- initialization procedure.
8143 Set_Ekind (Def_Id, Ekind (T));
8145 if For_Access and then Within_Init_Proc then
8148 Append_Elmt (Def_Id, Private_Dependents (T));
8152 Set_Etype (Def_Id, T);
8153 Init_Size_Align (Def_Id);
8154 Set_Has_Discriminants (Def_Id, Has_Discrs);
8155 Set_Is_Constrained (Def_Id, Constrained);
8157 Set_First_Entity (Def_Id, First_Entity (T));
8158 Set_Last_Entity (Def_Id, Last_Entity (T));
8160 -- If the subtype is the completion of a private declaration, there may
8161 -- have been representation clauses for the partial view, and they must
8162 -- be preserved. Build_Derived_Type chains the inherited clauses with
8163 -- the ones appearing on the extension. If this comes from a subtype
8164 -- declaration, all clauses are inherited.
8166 if No (First_Rep_Item (Def_Id)) then
8167 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
8170 if Is_Tagged_Type (T) then
8171 Set_Is_Tagged_Type (Def_Id);
8172 Make_Class_Wide_Type (Def_Id);
8175 Set_Stored_Constraint (Def_Id, No_Elist);
8178 Set_Discriminant_Constraint (Def_Id, Elist);
8179 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
8182 if Is_Tagged_Type (T) then
8184 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
8185 -- concurrent record type (which has the list of primitive
8188 if Ada_Version >= Ada_05
8189 and then Is_Concurrent_Type (T)
8191 Set_Corresponding_Record_Type (Def_Id,
8192 Corresponding_Record_Type (T));
8194 Set_Primitive_Operations (Def_Id, Primitive_Operations (T));
8197 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
8200 -- Subtypes introduced by component declarations do not need to be
8201 -- marked as delayed, and do not get freeze nodes, because the semantics
8202 -- verifies that the parents of the subtypes are frozen before the
8203 -- enclosing record is frozen.
8205 if not Is_Type (Scope (Def_Id)) then
8206 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
8208 if Is_Private_Type (T)
8209 and then Present (Full_View (T))
8211 Conditional_Delay (Def_Id, Full_View (T));
8213 Conditional_Delay (Def_Id, T);
8217 if Is_Record_Type (T) then
8218 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
8221 and then not Is_Empty_Elmt_List (Elist)
8222 and then not For_Access
8224 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
8225 elsif not For_Access then
8226 Set_Cloned_Subtype (Def_Id, T);
8229 end Build_Discriminated_Subtype;
8231 ---------------------------
8232 -- Build_Itype_Reference --
8233 ---------------------------
8235 procedure Build_Itype_Reference
8239 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
8241 Set_Itype (IR, Ityp);
8242 Insert_After (Nod, IR);
8243 end Build_Itype_Reference;
8245 ------------------------
8246 -- Build_Scalar_Bound --
8247 ------------------------
8249 function Build_Scalar_Bound
8252 Der_T : Entity_Id) return Node_Id
8254 New_Bound : Entity_Id;
8257 -- Note: not clear why this is needed, how can the original bound
8258 -- be unanalyzed at this point? and if it is, what business do we
8259 -- have messing around with it? and why is the base type of the
8260 -- parent type the right type for the resolution. It probably is
8261 -- not! It is OK for the new bound we are creating, but not for
8262 -- the old one??? Still if it never happens, no problem!
8264 Analyze_And_Resolve (Bound, Base_Type (Par_T));
8266 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
8267 New_Bound := New_Copy (Bound);
8268 Set_Etype (New_Bound, Der_T);
8269 Set_Analyzed (New_Bound);
8271 elsif Is_Entity_Name (Bound) then
8272 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
8274 -- The following is almost certainly wrong. What business do we have
8275 -- relocating a node (Bound) that is presumably still attached to
8276 -- the tree elsewhere???
8279 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
8282 Set_Etype (New_Bound, Der_T);
8284 end Build_Scalar_Bound;
8286 --------------------------------
8287 -- Build_Underlying_Full_View --
8288 --------------------------------
8290 procedure Build_Underlying_Full_View
8295 Loc : constant Source_Ptr := Sloc (N);
8296 Subt : constant Entity_Id :=
8297 Make_Defining_Identifier
8298 (Loc, New_External_Name (Chars (Typ), 'S'));
8305 procedure Set_Discriminant_Name (Id : Node_Id);
8306 -- If the derived type has discriminants, they may rename discriminants
8307 -- of the parent. When building the full view of the parent, we need to
8308 -- recover the names of the original discriminants if the constraint is
8309 -- given by named associations.
8311 ---------------------------
8312 -- Set_Discriminant_Name --
8313 ---------------------------
8315 procedure Set_Discriminant_Name (Id : Node_Id) is
8319 Set_Original_Discriminant (Id, Empty);
8321 if Has_Discriminants (Typ) then
8322 Disc := First_Discriminant (Typ);
8323 while Present (Disc) loop
8324 if Chars (Disc) = Chars (Id)
8325 and then Present (Corresponding_Discriminant (Disc))
8327 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
8329 Next_Discriminant (Disc);
8332 end Set_Discriminant_Name;
8334 -- Start of processing for Build_Underlying_Full_View
8337 if Nkind (N) = N_Full_Type_Declaration then
8338 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
8340 elsif Nkind (N) = N_Subtype_Declaration then
8341 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
8343 elsif Nkind (N) = N_Component_Declaration then
8346 (Constraint (Subtype_Indication (Component_Definition (N))));
8349 raise Program_Error;
8352 C := First (Constraints (Constr));
8353 while Present (C) loop
8354 if Nkind (C) = N_Discriminant_Association then
8355 Id := First (Selector_Names (C));
8356 while Present (Id) loop
8357 Set_Discriminant_Name (Id);
8366 Make_Subtype_Declaration (Loc,
8367 Defining_Identifier => Subt,
8368 Subtype_Indication =>
8369 Make_Subtype_Indication (Loc,
8370 Subtype_Mark => New_Reference_To (Par, Loc),
8371 Constraint => New_Copy_Tree (Constr)));
8373 -- If this is a component subtype for an outer itype, it is not
8374 -- a list member, so simply set the parent link for analysis: if
8375 -- the enclosing type does not need to be in a declarative list,
8376 -- neither do the components.
8378 if Is_List_Member (N)
8379 and then Nkind (N) /= N_Component_Declaration
8381 Insert_Before (N, Indic);
8383 Set_Parent (Indic, Parent (N));
8387 Set_Underlying_Full_View (Typ, Full_View (Subt));
8388 end Build_Underlying_Full_View;
8390 -------------------------------
8391 -- Check_Abstract_Overriding --
8392 -------------------------------
8394 procedure Check_Abstract_Overriding (T : Entity_Id) is
8395 Alias_Subp : Entity_Id;
8402 Op_List := Primitive_Operations (T);
8404 -- Loop to check primitive operations
8406 Elmt := First_Elmt (Op_List);
8407 while Present (Elmt) loop
8408 Subp := Node (Elmt);
8409 Alias_Subp := Alias (Subp);
8411 -- Inherited subprograms are identified by the fact that they do not
8412 -- come from source, and the associated source location is the
8413 -- location of the first subtype of the derived type.
8415 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
8416 -- subprograms that "require overriding".
8418 -- Special exception, do not complain about failure to override the
8419 -- stream routines _Input and _Output, as well as the primitive
8420 -- operations used in dispatching selects since we always provide
8421 -- automatic overridings for these subprograms.
8423 -- Also ignore this rule for convention CIL since .NET libraries
8424 -- do bizarre things with interfaces???
8426 -- The partial view of T may have been a private extension, for
8427 -- which inherited functions dispatching on result are abstract.
8428 -- If the full view is a null extension, there is no need for
8429 -- overriding in Ada2005, but wrappers need to be built for them
8430 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
8432 if Is_Null_Extension (T)
8433 and then Has_Controlling_Result (Subp)
8434 and then Ada_Version >= Ada_05
8435 and then Present (Alias_Subp)
8436 and then not Comes_From_Source (Subp)
8437 and then not Is_Abstract_Subprogram (Alias_Subp)
8438 and then not Is_Access_Type (Etype (Subp))
8442 -- Ada 2005 (AI-251): Internal entities of interfaces need no
8443 -- processing because this check is done with the aliased
8446 elsif Present (Interface_Alias (Subp)) then
8449 elsif (Is_Abstract_Subprogram (Subp)
8450 or else Requires_Overriding (Subp)
8452 (Has_Controlling_Result (Subp)
8453 and then Present (Alias_Subp)
8454 and then not Comes_From_Source (Subp)
8455 and then Sloc (Subp) = Sloc (First_Subtype (T))))
8456 and then not Is_TSS (Subp, TSS_Stream_Input)
8457 and then not Is_TSS (Subp, TSS_Stream_Output)
8458 and then not Is_Abstract_Type (T)
8459 and then Convention (T) /= Convention_CIL
8460 and then not Is_Predefined_Interface_Primitive (Subp)
8462 -- Ada 2005 (AI-251): Do not consider hidden entities associated
8463 -- with abstract interface types because the check will be done
8464 -- with the aliased entity (otherwise we generate a duplicated
8467 and then not Present (Interface_Alias (Subp))
8469 if Present (Alias_Subp) then
8471 -- Only perform the check for a derived subprogram when the
8472 -- type has an explicit record extension. This avoids incorrect
8473 -- flagging of abstract subprograms for the case of a type
8474 -- without an extension that is derived from a formal type
8475 -- with a tagged actual (can occur within a private part).
8477 -- Ada 2005 (AI-391): In the case of an inherited function with
8478 -- a controlling result of the type, the rule does not apply if
8479 -- the type is a null extension (unless the parent function
8480 -- itself is abstract, in which case the function must still be
8481 -- be overridden). The expander will generate an overriding
8482 -- wrapper function calling the parent subprogram (see
8483 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
8485 Type_Def := Type_Definition (Parent (T));
8487 if Nkind (Type_Def) = N_Derived_Type_Definition
8488 and then Present (Record_Extension_Part (Type_Def))
8490 (Ada_Version < Ada_05
8491 or else not Is_Null_Extension (T)
8492 or else Ekind (Subp) = E_Procedure
8493 or else not Has_Controlling_Result (Subp)
8494 or else Is_Abstract_Subprogram (Alias_Subp)
8495 or else Requires_Overriding (Subp)
8496 or else Is_Access_Type (Etype (Subp)))
8498 -- Avoid reporting error in case of abstract predefined
8499 -- primitive inherited from interface type because the
8500 -- body of internally generated predefined primitives
8501 -- of tagged types are generated later by Freeze_Type
8503 if Is_Interface (Root_Type (T))
8504 and then Is_Abstract_Subprogram (Subp)
8505 and then Is_Predefined_Dispatching_Operation (Subp)
8506 and then not Comes_From_Source (Ultimate_Alias (Subp))
8512 ("type must be declared abstract or & overridden",
8515 -- Traverse the whole chain of aliased subprograms to
8516 -- complete the error notification. This is especially
8517 -- useful for traceability of the chain of entities when
8518 -- the subprogram corresponds with an interface
8519 -- subprogram (which may be defined in another package).
8521 if Present (Alias_Subp) then
8527 while Present (Alias (E)) loop
8528 Error_Msg_Sloc := Sloc (E);
8530 ("\& has been inherited #", T, Subp);
8534 Error_Msg_Sloc := Sloc (E);
8536 ("\& has been inherited from subprogram #",
8542 -- Ada 2005 (AI-345): Protected or task type implementing
8543 -- abstract interfaces.
8545 elsif Is_Concurrent_Record_Type (T)
8546 and then Present (Interfaces (T))
8548 -- The controlling formal of Subp must be of mode "out",
8549 -- "in out" or an access-to-variable to be overridden.
8551 -- Error message below needs rewording (remember comma
8552 -- in -gnatj mode) ???
8554 if Ekind (First_Formal (Subp)) = E_In_Parameter
8555 and then Ekind (Subp) /= E_Function
8557 if not Is_Predefined_Dispatching_Operation (Subp) then
8559 ("first formal of & must be of mode `OUT`, " &
8560 "`IN OUT` or access-to-variable", T, Subp);
8562 ("\to be overridden by protected procedure or " &
8563 "entry (RM 9.4(11.9/2))", T);
8566 -- Some other kind of overriding failure
8570 ("interface subprogram & must be overridden",
8573 -- Examine primitive operations of synchronized type,
8574 -- to find homonyms that have the wrong profile.
8581 First_Entity (Corresponding_Concurrent_Type (T));
8582 while Present (Prim) loop
8583 if Chars (Prim) = Chars (Subp) then
8585 ("profile is not type conformant with "
8586 & "prefixed view profile of "
8587 & "inherited operation&", Prim, Subp);
8597 Error_Msg_Node_2 := T;
8599 ("abstract subprogram& not allowed for type&", Subp);
8601 -- Also post unconditional warning on the type (unconditional
8602 -- so that if there are more than one of these cases, we get
8603 -- them all, and not just the first one).
8605 Error_Msg_Node_2 := Subp;
8606 Error_Msg_N ("nonabstract type& has abstract subprogram&!", T);
8610 -- Ada 2005 (AI05-0030): Inspect hidden subprograms which provide
8611 -- the mapping between interface and implementing type primitives.
8612 -- If the interface alias is marked as Implemented_By_Entry, the
8613 -- alias must be an entry wrapper.
8615 if Ada_Version >= Ada_05
8616 and then Is_Hidden (Subp)
8617 and then Present (Interface_Alias (Subp))
8618 and then Implemented_By_Entry (Interface_Alias (Subp))
8619 and then Present (Alias_Subp)
8621 (not Is_Primitive_Wrapper (Alias_Subp)
8622 or else Ekind (Wrapped_Entity (Alias_Subp)) /= E_Entry)
8625 Error_Ent : Entity_Id := T;
8628 if Is_Concurrent_Record_Type (Error_Ent) then
8629 Error_Ent := Corresponding_Concurrent_Type (Error_Ent);
8632 Error_Msg_Node_2 := Interface_Alias (Subp);
8634 ("type & must implement abstract subprogram & with an entry",
8635 Error_Ent, Error_Ent);
8641 end Check_Abstract_Overriding;
8643 ------------------------------------------------
8644 -- Check_Access_Discriminant_Requires_Limited --
8645 ------------------------------------------------
8647 procedure Check_Access_Discriminant_Requires_Limited
8652 -- A discriminant_specification for an access discriminant shall appear
8653 -- only in the declaration for a task or protected type, or for a type
8654 -- with the reserved word 'limited' in its definition or in one of its
8655 -- ancestors. (RM 3.7(10))
8657 if Nkind (Discriminant_Type (D)) = N_Access_Definition
8658 and then not Is_Concurrent_Type (Current_Scope)
8659 and then not Is_Concurrent_Record_Type (Current_Scope)
8660 and then not Is_Limited_Record (Current_Scope)
8661 and then Ekind (Current_Scope) /= E_Limited_Private_Type
8664 ("access discriminants allowed only for limited types", Loc);
8666 end Check_Access_Discriminant_Requires_Limited;
8668 -----------------------------------
8669 -- Check_Aliased_Component_Types --
8670 -----------------------------------
8672 procedure Check_Aliased_Component_Types (T : Entity_Id) is
8676 -- ??? Also need to check components of record extensions, but not
8677 -- components of protected types (which are always limited).
8679 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
8680 -- types to be unconstrained. This is safe because it is illegal to
8681 -- create access subtypes to such types with explicit discriminant
8684 if not Is_Limited_Type (T) then
8685 if Ekind (T) = E_Record_Type then
8686 C := First_Component (T);
8687 while Present (C) loop
8689 and then Has_Discriminants (Etype (C))
8690 and then not Is_Constrained (Etype (C))
8691 and then not In_Instance_Body
8692 and then Ada_Version < Ada_05
8695 ("aliased component must be constrained (RM 3.6(11))",
8702 elsif Ekind (T) = E_Array_Type then
8703 if Has_Aliased_Components (T)
8704 and then Has_Discriminants (Component_Type (T))
8705 and then not Is_Constrained (Component_Type (T))
8706 and then not In_Instance_Body
8707 and then Ada_Version < Ada_05
8710 ("aliased component type must be constrained (RM 3.6(11))",
8715 end Check_Aliased_Component_Types;
8717 ----------------------
8718 -- Check_Completion --
8719 ----------------------
8721 procedure Check_Completion (Body_Id : Node_Id := Empty) is
8724 procedure Post_Error;
8725 -- Post error message for lack of completion for entity E
8731 procedure Post_Error is
8733 procedure Missing_Body;
8734 -- Output missing body message
8740 procedure Missing_Body is
8742 -- Spec is in same unit, so we can post on spec
8744 if In_Same_Source_Unit (Body_Id, E) then
8745 Error_Msg_N ("missing body for &", E);
8747 -- Spec is in a separate unit, so we have to post on the body
8750 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
8754 -- Start of processing for Post_Error
8757 if not Comes_From_Source (E) then
8759 if Ekind_In (E, E_Task_Type, E_Protected_Type) then
8760 -- It may be an anonymous protected type created for a
8761 -- single variable. Post error on variable, if present.
8767 Var := First_Entity (Current_Scope);
8768 while Present (Var) loop
8769 exit when Etype (Var) = E
8770 and then Comes_From_Source (Var);
8775 if Present (Var) then
8782 -- If a generated entity has no completion, then either previous
8783 -- semantic errors have disabled the expansion phase, or else we had
8784 -- missing subunits, or else we are compiling without expansion,
8785 -- or else something is very wrong.
8787 if not Comes_From_Source (E) then
8789 (Serious_Errors_Detected > 0
8790 or else Configurable_Run_Time_Violations > 0
8791 or else Subunits_Missing
8792 or else not Expander_Active);
8795 -- Here for source entity
8798 -- Here if no body to post the error message, so we post the error
8799 -- on the declaration that has no completion. This is not really
8800 -- the right place to post it, think about this later ???
8802 if No (Body_Id) then
8805 ("missing full declaration for }", Parent (E), E);
8807 Error_Msg_NE ("missing body for &", Parent (E), E);
8810 -- Package body has no completion for a declaration that appears
8811 -- in the corresponding spec. Post error on the body, with a
8812 -- reference to the non-completed declaration.
8815 Error_Msg_Sloc := Sloc (E);
8818 Error_Msg_NE ("missing full declaration for }!", Body_Id, E);
8820 elsif Is_Overloadable (E)
8821 and then Current_Entity_In_Scope (E) /= E
8823 -- It may be that the completion is mistyped and appears as
8824 -- a distinct overloading of the entity.
8827 Candidate : constant Entity_Id :=
8828 Current_Entity_In_Scope (E);
8829 Decl : constant Node_Id :=
8830 Unit_Declaration_Node (Candidate);
8833 if Is_Overloadable (Candidate)
8834 and then Ekind (Candidate) = Ekind (E)
8835 and then Nkind (Decl) = N_Subprogram_Body
8836 and then Acts_As_Spec (Decl)
8838 Check_Type_Conformant (Candidate, E);
8852 -- Start of processing for Check_Completion
8855 E := First_Entity (Current_Scope);
8856 while Present (E) loop
8857 if Is_Intrinsic_Subprogram (E) then
8860 -- The following situation requires special handling: a child unit
8861 -- that appears in the context clause of the body of its parent:
8863 -- procedure Parent.Child (...);
8865 -- with Parent.Child;
8866 -- package body Parent is
8868 -- Here Parent.Child appears as a local entity, but should not be
8869 -- flagged as requiring completion, because it is a compilation
8872 -- Ignore missing completion for a subprogram that does not come from
8873 -- source (including the _Call primitive operation of RAS types,
8874 -- which has to have the flag Comes_From_Source for other purposes):
8875 -- we assume that the expander will provide the missing completion.
8876 -- In case of previous errors, other expansion actions that provide
8877 -- bodies for null procedures with not be invoked, so inhibit message
8879 -- Note that E_Operator is not in the list that follows, because
8880 -- this kind is reserved for predefined operators, that are
8881 -- intrinsic and do not need completion.
8883 elsif Ekind (E) = E_Function
8884 or else Ekind (E) = E_Procedure
8885 or else Ekind (E) = E_Generic_Function
8886 or else Ekind (E) = E_Generic_Procedure
8888 if Has_Completion (E) then
8891 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
8894 elsif Is_Subprogram (E)
8895 and then (not Comes_From_Source (E)
8896 or else Chars (E) = Name_uCall)
8901 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
8905 elsif Nkind (Parent (E)) = N_Procedure_Specification
8906 and then Null_Present (Parent (E))
8907 and then Serious_Errors_Detected > 0
8915 elsif Is_Entry (E) then
8916 if not Has_Completion (E) and then
8917 (Ekind (Scope (E)) = E_Protected_Object
8918 or else Ekind (Scope (E)) = E_Protected_Type)
8923 elsif Is_Package_Or_Generic_Package (E) then
8924 if Unit_Requires_Body (E) then
8925 if not Has_Completion (E)
8926 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
8932 elsif not Is_Child_Unit (E) then
8933 May_Need_Implicit_Body (E);
8936 elsif Ekind (E) = E_Incomplete_Type
8937 and then No (Underlying_Type (E))
8941 elsif (Ekind (E) = E_Task_Type or else
8942 Ekind (E) = E_Protected_Type)
8943 and then not Has_Completion (E)
8947 -- A single task declared in the current scope is a constant, verify
8948 -- that the body of its anonymous type is in the same scope. If the
8949 -- task is defined elsewhere, this may be a renaming declaration for
8950 -- which no completion is needed.
8952 elsif Ekind (E) = E_Constant
8953 and then Ekind (Etype (E)) = E_Task_Type
8954 and then not Has_Completion (Etype (E))
8955 and then Scope (Etype (E)) = Current_Scope
8959 elsif Ekind (E) = E_Protected_Object
8960 and then not Has_Completion (Etype (E))
8964 elsif Ekind (E) = E_Record_Type then
8965 if Is_Tagged_Type (E) then
8966 Check_Abstract_Overriding (E);
8967 Check_Conventions (E);
8970 Check_Aliased_Component_Types (E);
8972 elsif Ekind (E) = E_Array_Type then
8973 Check_Aliased_Component_Types (E);
8979 end Check_Completion;
8981 ----------------------------
8982 -- Check_Delta_Expression --
8983 ----------------------------
8985 procedure Check_Delta_Expression (E : Node_Id) is
8987 if not (Is_Real_Type (Etype (E))) then
8988 Wrong_Type (E, Any_Real);
8990 elsif not Is_OK_Static_Expression (E) then
8991 Flag_Non_Static_Expr
8992 ("non-static expression used for delta value!", E);
8994 elsif not UR_Is_Positive (Expr_Value_R (E)) then
8995 Error_Msg_N ("delta expression must be positive", E);
9001 -- If any of above errors occurred, then replace the incorrect
9002 -- expression by the real 0.1, which should prevent further errors.
9005 Make_Real_Literal (Sloc (E), Ureal_Tenth));
9006 Analyze_And_Resolve (E, Standard_Float);
9007 end Check_Delta_Expression;
9009 -----------------------------
9010 -- Check_Digits_Expression --
9011 -----------------------------
9013 procedure Check_Digits_Expression (E : Node_Id) is
9015 if not (Is_Integer_Type (Etype (E))) then
9016 Wrong_Type (E, Any_Integer);
9018 elsif not Is_OK_Static_Expression (E) then
9019 Flag_Non_Static_Expr
9020 ("non-static expression used for digits value!", E);
9022 elsif Expr_Value (E) <= 0 then
9023 Error_Msg_N ("digits value must be greater than zero", E);
9029 -- If any of above errors occurred, then replace the incorrect
9030 -- expression by the integer 1, which should prevent further errors.
9032 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
9033 Analyze_And_Resolve (E, Standard_Integer);
9035 end Check_Digits_Expression;
9037 --------------------------
9038 -- Check_Initialization --
9039 --------------------------
9041 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
9043 if Is_Limited_Type (T)
9044 and then not In_Instance
9045 and then not In_Inlined_Body
9047 if not OK_For_Limited_Init (T, Exp) then
9049 -- In GNAT mode, this is just a warning, to allow it to be evilly
9050 -- turned off. Otherwise it is a real error.
9054 ("?cannot initialize entities of limited type!", Exp);
9056 elsif Ada_Version < Ada_05 then
9058 ("cannot initialize entities of limited type", Exp);
9059 Explain_Limited_Type (T, Exp);
9062 -- Specialize error message according to kind of illegal
9063 -- initial expression.
9065 if Nkind (Exp) = N_Type_Conversion
9066 and then Nkind (Expression (Exp)) = N_Function_Call
9069 ("illegal context for call"
9070 & " to function with limited result", Exp);
9074 ("initialization of limited object requires aggregate "
9075 & "or function call", Exp);
9080 end Check_Initialization;
9082 ----------------------
9083 -- Check_Interfaces --
9084 ----------------------
9086 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
9087 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
9090 Iface_Def : Node_Id;
9091 Iface_Typ : Entity_Id;
9092 Parent_Node : Node_Id;
9094 Is_Task : Boolean := False;
9095 -- Set True if parent type or any progenitor is a task interface
9097 Is_Protected : Boolean := False;
9098 -- Set True if parent type or any progenitor is a protected interface
9100 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
9101 -- Check that a progenitor is compatible with declaration.
9102 -- Error is posted on Error_Node.
9108 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
9109 Iface_Id : constant Entity_Id :=
9110 Defining_Identifier (Parent (Iface_Def));
9114 if Nkind (N) = N_Private_Extension_Declaration then
9117 Type_Def := Type_Definition (N);
9120 if Is_Task_Interface (Iface_Id) then
9123 elsif Is_Protected_Interface (Iface_Id) then
9124 Is_Protected := True;
9127 if Is_Synchronized_Interface (Iface_Id) then
9129 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
9130 -- extension derived from a synchronized interface must explicitly
9131 -- be declared synchronized, because the full view will be a
9132 -- synchronized type.
9134 if Nkind (N) = N_Private_Extension_Declaration then
9135 if not Synchronized_Present (N) then
9137 ("private extension of& must be explicitly synchronized",
9141 -- However, by 3.9.4(16/2), a full type that is a record extension
9142 -- is never allowed to derive from a synchronized interface (note
9143 -- that interfaces must be excluded from this check, because those
9144 -- are represented by derived type definitions in some cases).
9146 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
9147 and then not Interface_Present (Type_Definition (N))
9149 Error_Msg_N ("record extension cannot derive from synchronized"
9150 & " interface", Error_Node);
9154 -- Check that the characteristics of the progenitor are compatible
9155 -- with the explicit qualifier in the declaration.
9156 -- The check only applies to qualifiers that come from source.
9157 -- Limited_Present also appears in the declaration of corresponding
9158 -- records, and the check does not apply to them.
9160 if Limited_Present (Type_Def)
9162 Is_Concurrent_Record_Type (Defining_Identifier (N))
9164 if Is_Limited_Interface (Parent_Type)
9165 and then not Is_Limited_Interface (Iface_Id)
9168 ("progenitor& must be limited interface",
9169 Error_Node, Iface_Id);
9172 (Task_Present (Iface_Def)
9173 or else Protected_Present (Iface_Def)
9174 or else Synchronized_Present (Iface_Def))
9175 and then Nkind (N) /= N_Private_Extension_Declaration
9176 and then not Error_Posted (N)
9179 ("progenitor& must be limited interface",
9180 Error_Node, Iface_Id);
9183 -- Protected interfaces can only inherit from limited, synchronized
9184 -- or protected interfaces.
9186 elsif Nkind (N) = N_Full_Type_Declaration
9187 and then Protected_Present (Type_Def)
9189 if Limited_Present (Iface_Def)
9190 or else Synchronized_Present (Iface_Def)
9191 or else Protected_Present (Iface_Def)
9195 elsif Task_Present (Iface_Def) then
9196 Error_Msg_N ("(Ada 2005) protected interface cannot inherit"
9197 & " from task interface", Error_Node);
9200 Error_Msg_N ("(Ada 2005) protected interface cannot inherit"
9201 & " from non-limited interface", Error_Node);
9204 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
9205 -- limited and synchronized.
9207 elsif Synchronized_Present (Type_Def) then
9208 if Limited_Present (Iface_Def)
9209 or else Synchronized_Present (Iface_Def)
9213 elsif Protected_Present (Iface_Def)
9214 and then Nkind (N) /= N_Private_Extension_Declaration
9216 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9217 & " from protected interface", Error_Node);
9219 elsif Task_Present (Iface_Def)
9220 and then Nkind (N) /= N_Private_Extension_Declaration
9222 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9223 & " from task interface", Error_Node);
9225 elsif not Is_Limited_Interface (Iface_Id) then
9226 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9227 & " from non-limited interface", Error_Node);
9230 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
9231 -- synchronized or task interfaces.
9233 elsif Nkind (N) = N_Full_Type_Declaration
9234 and then Task_Present (Type_Def)
9236 if Limited_Present (Iface_Def)
9237 or else Synchronized_Present (Iface_Def)
9238 or else Task_Present (Iface_Def)
9242 elsif Protected_Present (Iface_Def) then
9243 Error_Msg_N ("(Ada 2005) task interface cannot inherit from"
9244 & " protected interface", Error_Node);
9247 Error_Msg_N ("(Ada 2005) task interface cannot inherit from"
9248 & " non-limited interface", Error_Node);
9253 -- Start of processing for Check_Interfaces
9256 if Is_Interface (Parent_Type) then
9257 if Is_Task_Interface (Parent_Type) then
9260 elsif Is_Protected_Interface (Parent_Type) then
9261 Is_Protected := True;
9265 if Nkind (N) = N_Private_Extension_Declaration then
9267 -- Check that progenitors are compatible with declaration
9269 Iface := First (Interface_List (Def));
9270 while Present (Iface) loop
9271 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
9273 Parent_Node := Parent (Base_Type (Iface_Typ));
9274 Iface_Def := Type_Definition (Parent_Node);
9276 if not Is_Interface (Iface_Typ) then
9277 Diagnose_Interface (Iface, Iface_Typ);
9280 Check_Ifaces (Iface_Def, Iface);
9286 if Is_Task and Is_Protected then
9288 ("type cannot derive from task and protected interface", N);
9294 -- Full type declaration of derived type.
9295 -- Check compatibility with parent if it is interface type
9297 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
9298 and then Is_Interface (Parent_Type)
9300 Parent_Node := Parent (Parent_Type);
9302 -- More detailed checks for interface varieties
9305 (Iface_Def => Type_Definition (Parent_Node),
9306 Error_Node => Subtype_Indication (Type_Definition (N)));
9309 Iface := First (Interface_List (Def));
9310 while Present (Iface) loop
9311 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
9313 Parent_Node := Parent (Base_Type (Iface_Typ));
9314 Iface_Def := Type_Definition (Parent_Node);
9316 if not Is_Interface (Iface_Typ) then
9317 Diagnose_Interface (Iface, Iface_Typ);
9320 -- "The declaration of a specific descendant of an interface
9321 -- type freezes the interface type" RM 13.14
9323 Freeze_Before (N, Iface_Typ);
9324 Check_Ifaces (Iface_Def, Error_Node => Iface);
9330 if Is_Task and Is_Protected then
9332 ("type cannot derive from task and protected interface", N);
9334 end Check_Interfaces;
9336 ------------------------------------
9337 -- Check_Or_Process_Discriminants --
9338 ------------------------------------
9340 -- If an incomplete or private type declaration was already given for the
9341 -- type, the discriminants may have already been processed if they were
9342 -- present on the incomplete declaration. In this case a full conformance
9343 -- check is performed otherwise just process them.
9345 procedure Check_Or_Process_Discriminants
9348 Prev : Entity_Id := Empty)
9351 if Has_Discriminants (T) then
9353 -- Make the discriminants visible to component declarations
9360 D := First_Discriminant (T);
9361 while Present (D) loop
9362 Prev := Current_Entity (D);
9363 Set_Current_Entity (D);
9364 Set_Is_Immediately_Visible (D);
9365 Set_Homonym (D, Prev);
9367 -- Ada 2005 (AI-230): Access discriminant allowed in
9368 -- non-limited record types.
9370 if Ada_Version < Ada_05 then
9372 -- This restriction gets applied to the full type here. It
9373 -- has already been applied earlier to the partial view.
9375 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
9378 Next_Discriminant (D);
9382 elsif Present (Discriminant_Specifications (N)) then
9383 Process_Discriminants (N, Prev);
9385 end Check_Or_Process_Discriminants;
9387 ----------------------
9388 -- Check_Real_Bound --
9389 ----------------------
9391 procedure Check_Real_Bound (Bound : Node_Id) is
9393 if not Is_Real_Type (Etype (Bound)) then
9395 ("bound in real type definition must be of real type", Bound);
9397 elsif not Is_OK_Static_Expression (Bound) then
9398 Flag_Non_Static_Expr
9399 ("non-static expression used for real type bound!", Bound);
9406 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
9408 Resolve (Bound, Standard_Float);
9409 end Check_Real_Bound;
9411 ------------------------------
9412 -- Complete_Private_Subtype --
9413 ------------------------------
9415 procedure Complete_Private_Subtype
9418 Full_Base : Entity_Id;
9419 Related_Nod : Node_Id)
9421 Save_Next_Entity : Entity_Id;
9422 Save_Homonym : Entity_Id;
9425 -- Set semantic attributes for (implicit) private subtype completion.
9426 -- If the full type has no discriminants, then it is a copy of the full
9427 -- view of the base. Otherwise, it is a subtype of the base with a
9428 -- possible discriminant constraint. Save and restore the original
9429 -- Next_Entity field of full to ensure that the calls to Copy_Node
9430 -- do not corrupt the entity chain.
9432 -- Note that the type of the full view is the same entity as the type of
9433 -- the partial view. In this fashion, the subtype has access to the
9434 -- correct view of the parent.
9436 Save_Next_Entity := Next_Entity (Full);
9437 Save_Homonym := Homonym (Priv);
9439 case Ekind (Full_Base) is
9440 when E_Record_Type |
9446 Copy_Node (Priv, Full);
9448 Set_Has_Discriminants (Full, Has_Discriminants (Full_Base));
9449 Set_First_Entity (Full, First_Entity (Full_Base));
9450 Set_Last_Entity (Full, Last_Entity (Full_Base));
9453 Copy_Node (Full_Base, Full);
9454 Set_Chars (Full, Chars (Priv));
9455 Conditional_Delay (Full, Priv);
9456 Set_Sloc (Full, Sloc (Priv));
9459 Set_Next_Entity (Full, Save_Next_Entity);
9460 Set_Homonym (Full, Save_Homonym);
9461 Set_Associated_Node_For_Itype (Full, Related_Nod);
9463 -- Set common attributes for all subtypes
9465 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
9467 -- The Etype of the full view is inconsistent. Gigi needs to see the
9468 -- structural full view, which is what the current scheme gives:
9469 -- the Etype of the full view is the etype of the full base. However,
9470 -- if the full base is a derived type, the full view then looks like
9471 -- a subtype of the parent, not a subtype of the full base. If instead
9474 -- Set_Etype (Full, Full_Base);
9476 -- then we get inconsistencies in the front-end (confusion between
9477 -- views). Several outstanding bugs are related to this ???
9479 Set_Is_First_Subtype (Full, False);
9480 Set_Scope (Full, Scope (Priv));
9481 Set_Size_Info (Full, Full_Base);
9482 Set_RM_Size (Full, RM_Size (Full_Base));
9483 Set_Is_Itype (Full);
9485 -- A subtype of a private-type-without-discriminants, whose full-view
9486 -- has discriminants with default expressions, is not constrained!
9488 if not Has_Discriminants (Priv) then
9489 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
9491 if Has_Discriminants (Full_Base) then
9492 Set_Discriminant_Constraint
9493 (Full, Discriminant_Constraint (Full_Base));
9495 -- The partial view may have been indefinite, the full view
9498 Set_Has_Unknown_Discriminants
9499 (Full, Has_Unknown_Discriminants (Full_Base));
9503 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
9504 Set_Depends_On_Private (Full, Has_Private_Component (Full));
9506 -- Freeze the private subtype entity if its parent is delayed, and not
9507 -- already frozen. We skip this processing if the type is an anonymous
9508 -- subtype of a record component, or is the corresponding record of a
9509 -- protected type, since ???
9511 if not Is_Type (Scope (Full)) then
9512 Set_Has_Delayed_Freeze (Full,
9513 Has_Delayed_Freeze (Full_Base)
9514 and then (not Is_Frozen (Full_Base)));
9517 Set_Freeze_Node (Full, Empty);
9518 Set_Is_Frozen (Full, False);
9519 Set_Full_View (Priv, Full);
9521 if Has_Discriminants (Full) then
9522 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
9523 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
9525 if Has_Unknown_Discriminants (Full) then
9526 Set_Discriminant_Constraint (Full, No_Elist);
9530 if Ekind (Full_Base) = E_Record_Type
9531 and then Has_Discriminants (Full_Base)
9532 and then Has_Discriminants (Priv) -- might not, if errors
9533 and then not Has_Unknown_Discriminants (Priv)
9534 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
9536 Create_Constrained_Components
9537 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
9539 -- If the full base is itself derived from private, build a congruent
9540 -- subtype of its underlying type, for use by the back end. For a
9541 -- constrained record component, the declaration cannot be placed on
9542 -- the component list, but it must nevertheless be built an analyzed, to
9543 -- supply enough information for Gigi to compute the size of component.
9545 elsif Ekind (Full_Base) in Private_Kind
9546 and then Is_Derived_Type (Full_Base)
9547 and then Has_Discriminants (Full_Base)
9548 and then (Ekind (Current_Scope) /= E_Record_Subtype)
9550 if not Is_Itype (Priv)
9552 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
9554 Build_Underlying_Full_View
9555 (Parent (Priv), Full, Etype (Full_Base));
9557 elsif Nkind (Related_Nod) = N_Component_Declaration then
9558 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
9561 elsif Is_Record_Type (Full_Base) then
9563 -- Show Full is simply a renaming of Full_Base
9565 Set_Cloned_Subtype (Full, Full_Base);
9568 -- It is unsafe to share to bounds of a scalar type, because the Itype
9569 -- is elaborated on demand, and if a bound is non-static then different
9570 -- orders of elaboration in different units will lead to different
9571 -- external symbols.
9573 if Is_Scalar_Type (Full_Base) then
9574 Set_Scalar_Range (Full,
9575 Make_Range (Sloc (Related_Nod),
9577 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
9579 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
9581 -- This completion inherits the bounds of the full parent, but if
9582 -- the parent is an unconstrained floating point type, so is the
9585 if Is_Floating_Point_Type (Full_Base) then
9586 Set_Includes_Infinities
9587 (Scalar_Range (Full), Has_Infinities (Full_Base));
9591 -- ??? It seems that a lot of fields are missing that should be copied
9592 -- from Full_Base to Full. Here are some that are introduced in a
9593 -- non-disruptive way but a cleanup is necessary.
9595 if Is_Tagged_Type (Full_Base) then
9596 Set_Is_Tagged_Type (Full);
9597 Set_Primitive_Operations (Full, Primitive_Operations (Full_Base));
9599 -- Inherit class_wide type of full_base in case the partial view was
9600 -- not tagged. Otherwise it has already been created when the private
9601 -- subtype was analyzed.
9603 if No (Class_Wide_Type (Full)) then
9604 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
9607 -- If this is a subtype of a protected or task type, constrain its
9608 -- corresponding record, unless this is a subtype without constraints,
9609 -- i.e. a simple renaming as with an actual subtype in an instance.
9611 elsif Is_Concurrent_Type (Full_Base) then
9612 if Has_Discriminants (Full)
9613 and then Present (Corresponding_Record_Type (Full_Base))
9615 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
9617 Set_Corresponding_Record_Type (Full,
9618 Constrain_Corresponding_Record
9619 (Full, Corresponding_Record_Type (Full_Base),
9620 Related_Nod, Full_Base));
9623 Set_Corresponding_Record_Type (Full,
9624 Corresponding_Record_Type (Full_Base));
9627 end Complete_Private_Subtype;
9629 ----------------------------
9630 -- Constant_Redeclaration --
9631 ----------------------------
9633 procedure Constant_Redeclaration
9638 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
9639 Obj_Def : constant Node_Id := Object_Definition (N);
9642 procedure Check_Possible_Deferred_Completion
9643 (Prev_Id : Entity_Id;
9644 Prev_Obj_Def : Node_Id;
9645 Curr_Obj_Def : Node_Id);
9646 -- Determine whether the two object definitions describe the partial
9647 -- and the full view of a constrained deferred constant. Generate
9648 -- a subtype for the full view and verify that it statically matches
9649 -- the subtype of the partial view.
9651 procedure Check_Recursive_Declaration (Typ : Entity_Id);
9652 -- If deferred constant is an access type initialized with an allocator,
9653 -- check whether there is an illegal recursion in the definition,
9654 -- through a default value of some record subcomponent. This is normally
9655 -- detected when generating init procs, but requires this additional
9656 -- mechanism when expansion is disabled.
9658 ----------------------------------------
9659 -- Check_Possible_Deferred_Completion --
9660 ----------------------------------------
9662 procedure Check_Possible_Deferred_Completion
9663 (Prev_Id : Entity_Id;
9664 Prev_Obj_Def : Node_Id;
9665 Curr_Obj_Def : Node_Id)
9668 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
9669 and then Present (Constraint (Prev_Obj_Def))
9670 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
9671 and then Present (Constraint (Curr_Obj_Def))
9674 Loc : constant Source_Ptr := Sloc (N);
9675 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'S');
9676 Decl : constant Node_Id :=
9677 Make_Subtype_Declaration (Loc,
9678 Defining_Identifier => Def_Id,
9679 Subtype_Indication =>
9680 Relocate_Node (Curr_Obj_Def));
9683 Insert_Before_And_Analyze (N, Decl);
9684 Set_Etype (Id, Def_Id);
9686 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
9687 Error_Msg_Sloc := Sloc (Prev_Id);
9688 Error_Msg_N ("subtype does not statically match deferred " &
9693 end Check_Possible_Deferred_Completion;
9695 ---------------------------------
9696 -- Check_Recursive_Declaration --
9697 ---------------------------------
9699 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
9703 if Is_Record_Type (Typ) then
9704 Comp := First_Component (Typ);
9705 while Present (Comp) loop
9706 if Comes_From_Source (Comp) then
9707 if Present (Expression (Parent (Comp)))
9708 and then Is_Entity_Name (Expression (Parent (Comp)))
9709 and then Entity (Expression (Parent (Comp))) = Prev
9711 Error_Msg_Sloc := Sloc (Parent (Comp));
9713 ("illegal circularity with declaration for&#",
9717 elsif Is_Record_Type (Etype (Comp)) then
9718 Check_Recursive_Declaration (Etype (Comp));
9722 Next_Component (Comp);
9725 end Check_Recursive_Declaration;
9727 -- Start of processing for Constant_Redeclaration
9730 if Nkind (Parent (Prev)) = N_Object_Declaration then
9731 if Nkind (Object_Definition
9732 (Parent (Prev))) = N_Subtype_Indication
9734 -- Find type of new declaration. The constraints of the two
9735 -- views must match statically, but there is no point in
9736 -- creating an itype for the full view.
9738 if Nkind (Obj_Def) = N_Subtype_Indication then
9739 Find_Type (Subtype_Mark (Obj_Def));
9740 New_T := Entity (Subtype_Mark (Obj_Def));
9743 Find_Type (Obj_Def);
9744 New_T := Entity (Obj_Def);
9750 -- The full view may impose a constraint, even if the partial
9751 -- view does not, so construct the subtype.
9753 New_T := Find_Type_Of_Object (Obj_Def, N);
9758 -- Current declaration is illegal, diagnosed below in Enter_Name
9764 -- If previous full declaration or a renaming declaration exists, or if
9765 -- a homograph is present, let Enter_Name handle it, either with an
9766 -- error or with the removal of an overridden implicit subprogram.
9768 if Ekind (Prev) /= E_Constant
9769 or else Nkind (Parent (Prev)) = N_Object_Renaming_Declaration
9770 or else Present (Expression (Parent (Prev)))
9771 or else Present (Full_View (Prev))
9775 -- Verify that types of both declarations match, or else that both types
9776 -- are anonymous access types whose designated subtypes statically match
9777 -- (as allowed in Ada 2005 by AI-385).
9779 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
9781 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
9782 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
9783 or else Is_Access_Constant (Etype (New_T)) /=
9784 Is_Access_Constant (Etype (Prev))
9785 or else Can_Never_Be_Null (Etype (New_T)) /=
9786 Can_Never_Be_Null (Etype (Prev))
9787 or else Null_Exclusion_Present (Parent (Prev)) /=
9788 Null_Exclusion_Present (Parent (Id))
9789 or else not Subtypes_Statically_Match
9790 (Designated_Type (Etype (Prev)),
9791 Designated_Type (Etype (New_T))))
9793 Error_Msg_Sloc := Sloc (Prev);
9794 Error_Msg_N ("type does not match declaration#", N);
9795 Set_Full_View (Prev, Id);
9796 Set_Etype (Id, Any_Type);
9799 Null_Exclusion_Present (Parent (Prev))
9800 and then not Null_Exclusion_Present (N)
9802 Error_Msg_Sloc := Sloc (Prev);
9803 Error_Msg_N ("null-exclusion does not match declaration#", N);
9804 Set_Full_View (Prev, Id);
9805 Set_Etype (Id, Any_Type);
9807 -- If so, process the full constant declaration
9810 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
9811 -- the deferred declaration is constrained, then the subtype defined
9812 -- by the subtype_indication in the full declaration shall match it
9815 Check_Possible_Deferred_Completion
9817 Prev_Obj_Def => Object_Definition (Parent (Prev)),
9818 Curr_Obj_Def => Obj_Def);
9820 Set_Full_View (Prev, Id);
9821 Set_Is_Public (Id, Is_Public (Prev));
9822 Set_Is_Internal (Id);
9823 Append_Entity (Id, Current_Scope);
9825 -- Check ALIASED present if present before (RM 7.4(7))
9827 if Is_Aliased (Prev)
9828 and then not Aliased_Present (N)
9830 Error_Msg_Sloc := Sloc (Prev);
9831 Error_Msg_N ("ALIASED required (see declaration#)", N);
9834 -- Check that placement is in private part and that the incomplete
9835 -- declaration appeared in the visible part.
9837 if Ekind (Current_Scope) = E_Package
9838 and then not In_Private_Part (Current_Scope)
9840 Error_Msg_Sloc := Sloc (Prev);
9842 ("full constant for declaration#"
9843 & " must be in private part", N);
9845 elsif Ekind (Current_Scope) = E_Package
9847 List_Containing (Parent (Prev)) /=
9848 Visible_Declarations
9849 (Specification (Unit_Declaration_Node (Current_Scope)))
9852 ("deferred constant must be declared in visible part",
9856 if Is_Access_Type (T)
9857 and then Nkind (Expression (N)) = N_Allocator
9859 Check_Recursive_Declaration (Designated_Type (T));
9862 end Constant_Redeclaration;
9864 ----------------------
9865 -- Constrain_Access --
9866 ----------------------
9868 procedure Constrain_Access
9869 (Def_Id : in out Entity_Id;
9871 Related_Nod : Node_Id)
9873 T : constant Entity_Id := Entity (Subtype_Mark (S));
9874 Desig_Type : constant Entity_Id := Designated_Type (T);
9875 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
9876 Constraint_OK : Boolean := True;
9878 function Has_Defaulted_Discriminants (Typ : Entity_Id) return Boolean;
9879 -- Simple predicate to test for defaulted discriminants
9880 -- Shouldn't this be in sem_util???
9882 ---------------------------------
9883 -- Has_Defaulted_Discriminants --
9884 ---------------------------------
9886 function Has_Defaulted_Discriminants (Typ : Entity_Id) return Boolean is
9888 return Has_Discriminants (Typ)
9889 and then Present (First_Discriminant (Typ))
9891 (Discriminant_Default_Value (First_Discriminant (Typ)));
9892 end Has_Defaulted_Discriminants;
9894 -- Start of processing for Constrain_Access
9897 if Is_Array_Type (Desig_Type) then
9898 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
9900 elsif (Is_Record_Type (Desig_Type)
9901 or else Is_Incomplete_Or_Private_Type (Desig_Type))
9902 and then not Is_Constrained (Desig_Type)
9904 -- ??? The following code is a temporary kludge to ignore a
9905 -- discriminant constraint on access type if it is constraining
9906 -- the current record. Avoid creating the implicit subtype of the
9907 -- record we are currently compiling since right now, we cannot
9908 -- handle these. For now, just return the access type itself.
9910 if Desig_Type = Current_Scope
9911 and then No (Def_Id)
9913 Set_Ekind (Desig_Subtype, E_Record_Subtype);
9914 Def_Id := Entity (Subtype_Mark (S));
9916 -- This call added to ensure that the constraint is analyzed
9917 -- (needed for a B test). Note that we still return early from
9918 -- this procedure to avoid recursive processing. ???
9920 Constrain_Discriminated_Type
9921 (Desig_Subtype, S, Related_Nod, For_Access => True);
9925 if (Ekind (T) = E_General_Access_Type
9926 or else Ada_Version >= Ada_05)
9927 and then Has_Private_Declaration (Desig_Type)
9928 and then In_Open_Scopes (Scope (Desig_Type))
9929 and then Has_Discriminants (Desig_Type)
9931 -- Enforce rule that the constraint is illegal if there is
9932 -- an unconstrained view of the designated type. This means
9933 -- that the partial view (either a private type declaration or
9934 -- a derivation from a private type) has no discriminants.
9935 -- (Defect Report 8652/0008, Technical Corrigendum 1, checked
9936 -- by ACATS B371001).
9938 -- Rule updated for Ada 2005: the private type is said to have
9939 -- a constrained partial view, given that objects of the type
9940 -- can be declared. Furthermore, the rule applies to all access
9941 -- types, unlike the rule concerning default discriminants.
9944 Pack : constant Node_Id :=
9945 Unit_Declaration_Node (Scope (Desig_Type));
9950 if Nkind (Pack) = N_Package_Declaration then
9951 Decls := Visible_Declarations (Specification (Pack));
9952 Decl := First (Decls);
9953 while Present (Decl) loop
9954 if (Nkind (Decl) = N_Private_Type_Declaration
9956 Chars (Defining_Identifier (Decl)) =
9960 (Nkind (Decl) = N_Full_Type_Declaration
9962 Chars (Defining_Identifier (Decl)) =
9964 and then Is_Derived_Type (Desig_Type)
9966 Has_Private_Declaration (Etype (Desig_Type)))
9968 if No (Discriminant_Specifications (Decl)) then
9970 ("cannot constrain general access type if " &
9971 "designated type has constrained partial view",
9984 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
9985 For_Access => True);
9987 elsif (Is_Task_Type (Desig_Type)
9988 or else Is_Protected_Type (Desig_Type))
9989 and then not Is_Constrained (Desig_Type)
9991 Constrain_Concurrent
9992 (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
9995 Error_Msg_N ("invalid constraint on access type", S);
9996 Desig_Subtype := Desig_Type; -- Ignore invalid constraint.
9997 Constraint_OK := False;
10000 if No (Def_Id) then
10001 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
10003 Set_Ekind (Def_Id, E_Access_Subtype);
10006 if Constraint_OK then
10007 Set_Etype (Def_Id, Base_Type (T));
10009 if Is_Private_Type (Desig_Type) then
10010 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
10013 Set_Etype (Def_Id, Any_Type);
10016 Set_Size_Info (Def_Id, T);
10017 Set_Is_Constrained (Def_Id, Constraint_OK);
10018 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
10019 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
10020 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
10022 Conditional_Delay (Def_Id, T);
10024 -- AI-363 : Subtypes of general access types whose designated types have
10025 -- default discriminants are disallowed. In instances, the rule has to
10026 -- be checked against the actual, of which T is the subtype. In a
10027 -- generic body, the rule is checked assuming that the actual type has
10028 -- defaulted discriminants.
10030 if Ada_Version >= Ada_05 or else Warn_On_Ada_2005_Compatibility then
10031 if Ekind (Base_Type (T)) = E_General_Access_Type
10032 and then Has_Defaulted_Discriminants (Desig_Type)
10034 if Ada_Version < Ada_05 then
10036 ("access subtype of general access type would not " &
10037 "be allowed in Ada 2005?", S);
10040 ("access subype of general access type not allowed", S);
10043 Error_Msg_N ("\discriminants have defaults", S);
10045 elsif Is_Access_Type (T)
10046 and then Is_Generic_Type (Desig_Type)
10047 and then Has_Discriminants (Desig_Type)
10048 and then In_Package_Body (Current_Scope)
10050 if Ada_Version < Ada_05 then
10052 ("access subtype would not be allowed in generic body " &
10053 "in Ada 2005?", S);
10056 ("access subtype not allowed in generic body", S);
10060 ("\designated type is a discriminated formal", S);
10063 end Constrain_Access;
10065 ---------------------
10066 -- Constrain_Array --
10067 ---------------------
10069 procedure Constrain_Array
10070 (Def_Id : in out Entity_Id;
10072 Related_Nod : Node_Id;
10073 Related_Id : Entity_Id;
10074 Suffix : Character)
10076 C : constant Node_Id := Constraint (SI);
10077 Number_Of_Constraints : Nat := 0;
10080 Constraint_OK : Boolean := True;
10083 T := Entity (Subtype_Mark (SI));
10085 if Ekind (T) in Access_Kind then
10086 T := Designated_Type (T);
10089 -- If an index constraint follows a subtype mark in a subtype indication
10090 -- then the type or subtype denoted by the subtype mark must not already
10091 -- impose an index constraint. The subtype mark must denote either an
10092 -- unconstrained array type or an access type whose designated type
10093 -- is such an array type... (RM 3.6.1)
10095 if Is_Constrained (T) then
10096 Error_Msg_N ("array type is already constrained", Subtype_Mark (SI));
10097 Constraint_OK := False;
10100 S := First (Constraints (C));
10101 while Present (S) loop
10102 Number_Of_Constraints := Number_Of_Constraints + 1;
10106 -- In either case, the index constraint must provide a discrete
10107 -- range for each index of the array type and the type of each
10108 -- discrete range must be the same as that of the corresponding
10109 -- index. (RM 3.6.1)
10111 if Number_Of_Constraints /= Number_Dimensions (T) then
10112 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
10113 Constraint_OK := False;
10116 S := First (Constraints (C));
10117 Index := First_Index (T);
10120 -- Apply constraints to each index type
10122 for J in 1 .. Number_Of_Constraints loop
10123 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
10131 if No (Def_Id) then
10133 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
10134 Set_Parent (Def_Id, Related_Nod);
10137 Set_Ekind (Def_Id, E_Array_Subtype);
10140 Set_Size_Info (Def_Id, (T));
10141 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
10142 Set_Etype (Def_Id, Base_Type (T));
10144 if Constraint_OK then
10145 Set_First_Index (Def_Id, First (Constraints (C)));
10147 Set_First_Index (Def_Id, First_Index (T));
10150 Set_Is_Constrained (Def_Id, True);
10151 Set_Is_Aliased (Def_Id, Is_Aliased (T));
10152 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
10154 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
10155 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
10157 -- A subtype does not inherit the packed_array_type of is parent. We
10158 -- need to initialize the attribute because if Def_Id is previously
10159 -- analyzed through a limited_with clause, it will have the attributes
10160 -- of an incomplete type, one of which is an Elist that overlaps the
10161 -- Packed_Array_Type field.
10163 Set_Packed_Array_Type (Def_Id, Empty);
10165 -- Build a freeze node if parent still needs one. Also make sure that
10166 -- the Depends_On_Private status is set because the subtype will need
10167 -- reprocessing at the time the base type does, and also we must set a
10168 -- conditional delay.
10170 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
10171 Conditional_Delay (Def_Id, T);
10172 end Constrain_Array;
10174 ------------------------------
10175 -- Constrain_Component_Type --
10176 ------------------------------
10178 function Constrain_Component_Type
10180 Constrained_Typ : Entity_Id;
10181 Related_Node : Node_Id;
10183 Constraints : Elist_Id) return Entity_Id
10185 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
10186 Compon_Type : constant Entity_Id := Etype (Comp);
10188 function Build_Constrained_Array_Type
10189 (Old_Type : Entity_Id) return Entity_Id;
10190 -- If Old_Type is an array type, one of whose indices is constrained
10191 -- by a discriminant, build an Itype whose constraint replaces the
10192 -- discriminant with its value in the constraint.
10194 function Build_Constrained_Discriminated_Type
10195 (Old_Type : Entity_Id) return Entity_Id;
10196 -- Ditto for record components
10198 function Build_Constrained_Access_Type
10199 (Old_Type : Entity_Id) return Entity_Id;
10200 -- Ditto for access types. Makes use of previous two functions, to
10201 -- constrain designated type.
10203 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
10204 -- T is an array or discriminated type, C is a list of constraints
10205 -- that apply to T. This routine builds the constrained subtype.
10207 function Is_Discriminant (Expr : Node_Id) return Boolean;
10208 -- Returns True if Expr is a discriminant
10210 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
10211 -- Find the value of discriminant Discrim in Constraint
10213 -----------------------------------
10214 -- Build_Constrained_Access_Type --
10215 -----------------------------------
10217 function Build_Constrained_Access_Type
10218 (Old_Type : Entity_Id) return Entity_Id
10220 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
10222 Desig_Subtype : Entity_Id;
10226 -- if the original access type was not embedded in the enclosing
10227 -- type definition, there is no need to produce a new access
10228 -- subtype. In fact every access type with an explicit constraint
10229 -- generates an itype whose scope is the enclosing record.
10231 if not Is_Type (Scope (Old_Type)) then
10234 elsif Is_Array_Type (Desig_Type) then
10235 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
10237 elsif Has_Discriminants (Desig_Type) then
10239 -- This may be an access type to an enclosing record type for
10240 -- which we are constructing the constrained components. Return
10241 -- the enclosing record subtype. This is not always correct,
10242 -- but avoids infinite recursion. ???
10244 Desig_Subtype := Any_Type;
10246 for J in reverse 0 .. Scope_Stack.Last loop
10247 Scop := Scope_Stack.Table (J).Entity;
10250 and then Base_Type (Scop) = Base_Type (Desig_Type)
10252 Desig_Subtype := Scop;
10255 exit when not Is_Type (Scop);
10258 if Desig_Subtype = Any_Type then
10260 Build_Constrained_Discriminated_Type (Desig_Type);
10267 if Desig_Subtype /= Desig_Type then
10269 -- The Related_Node better be here or else we won't be able
10270 -- to attach new itypes to a node in the tree.
10272 pragma Assert (Present (Related_Node));
10274 Itype := Create_Itype (E_Access_Subtype, Related_Node);
10276 Set_Etype (Itype, Base_Type (Old_Type));
10277 Set_Size_Info (Itype, (Old_Type));
10278 Set_Directly_Designated_Type (Itype, Desig_Subtype);
10279 Set_Depends_On_Private (Itype, Has_Private_Component
10281 Set_Is_Access_Constant (Itype, Is_Access_Constant
10284 -- The new itype needs freezing when it depends on a not frozen
10285 -- type and the enclosing subtype needs freezing.
10287 if Has_Delayed_Freeze (Constrained_Typ)
10288 and then not Is_Frozen (Constrained_Typ)
10290 Conditional_Delay (Itype, Base_Type (Old_Type));
10298 end Build_Constrained_Access_Type;
10300 ----------------------------------
10301 -- Build_Constrained_Array_Type --
10302 ----------------------------------
10304 function Build_Constrained_Array_Type
10305 (Old_Type : Entity_Id) return Entity_Id
10309 Old_Index : Node_Id;
10310 Range_Node : Node_Id;
10311 Constr_List : List_Id;
10313 Need_To_Create_Itype : Boolean := False;
10316 Old_Index := First_Index (Old_Type);
10317 while Present (Old_Index) loop
10318 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
10320 if Is_Discriminant (Lo_Expr)
10321 or else Is_Discriminant (Hi_Expr)
10323 Need_To_Create_Itype := True;
10326 Next_Index (Old_Index);
10329 if Need_To_Create_Itype then
10330 Constr_List := New_List;
10332 Old_Index := First_Index (Old_Type);
10333 while Present (Old_Index) loop
10334 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
10336 if Is_Discriminant (Lo_Expr) then
10337 Lo_Expr := Get_Discr_Value (Lo_Expr);
10340 if Is_Discriminant (Hi_Expr) then
10341 Hi_Expr := Get_Discr_Value (Hi_Expr);
10346 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
10348 Append (Range_Node, To => Constr_List);
10350 Next_Index (Old_Index);
10353 return Build_Subtype (Old_Type, Constr_List);
10358 end Build_Constrained_Array_Type;
10360 ------------------------------------------
10361 -- Build_Constrained_Discriminated_Type --
10362 ------------------------------------------
10364 function Build_Constrained_Discriminated_Type
10365 (Old_Type : Entity_Id) return Entity_Id
10368 Constr_List : List_Id;
10369 Old_Constraint : Elmt_Id;
10371 Need_To_Create_Itype : Boolean := False;
10374 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
10375 while Present (Old_Constraint) loop
10376 Expr := Node (Old_Constraint);
10378 if Is_Discriminant (Expr) then
10379 Need_To_Create_Itype := True;
10382 Next_Elmt (Old_Constraint);
10385 if Need_To_Create_Itype then
10386 Constr_List := New_List;
10388 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
10389 while Present (Old_Constraint) loop
10390 Expr := Node (Old_Constraint);
10392 if Is_Discriminant (Expr) then
10393 Expr := Get_Discr_Value (Expr);
10396 Append (New_Copy_Tree (Expr), To => Constr_List);
10398 Next_Elmt (Old_Constraint);
10401 return Build_Subtype (Old_Type, Constr_List);
10406 end Build_Constrained_Discriminated_Type;
10408 -------------------
10409 -- Build_Subtype --
10410 -------------------
10412 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
10414 Subtyp_Decl : Node_Id;
10415 Def_Id : Entity_Id;
10416 Btyp : Entity_Id := Base_Type (T);
10419 -- The Related_Node better be here or else we won't be able to
10420 -- attach new itypes to a node in the tree.
10422 pragma Assert (Present (Related_Node));
10424 -- If the view of the component's type is incomplete or private
10425 -- with unknown discriminants, then the constraint must be applied
10426 -- to the full type.
10428 if Has_Unknown_Discriminants (Btyp)
10429 and then Present (Underlying_Type (Btyp))
10431 Btyp := Underlying_Type (Btyp);
10435 Make_Subtype_Indication (Loc,
10436 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
10437 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
10439 Def_Id := Create_Itype (Ekind (T), Related_Node);
10442 Make_Subtype_Declaration (Loc,
10443 Defining_Identifier => Def_Id,
10444 Subtype_Indication => Indic);
10446 Set_Parent (Subtyp_Decl, Parent (Related_Node));
10448 -- Itypes must be analyzed with checks off (see package Itypes)
10450 Analyze (Subtyp_Decl, Suppress => All_Checks);
10455 ---------------------
10456 -- Get_Discr_Value --
10457 ---------------------
10459 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
10464 -- The discriminant may be declared for the type, in which case we
10465 -- find it by iterating over the list of discriminants. If the
10466 -- discriminant is inherited from a parent type, it appears as the
10467 -- corresponding discriminant of the current type. This will be the
10468 -- case when constraining an inherited component whose constraint is
10469 -- given by a discriminant of the parent.
10471 D := First_Discriminant (Typ);
10472 E := First_Elmt (Constraints);
10474 while Present (D) loop
10475 if D = Entity (Discrim)
10476 or else D = CR_Discriminant (Entity (Discrim))
10477 or else Corresponding_Discriminant (D) = Entity (Discrim)
10482 Next_Discriminant (D);
10486 -- The corresponding_Discriminant mechanism is incomplete, because
10487 -- the correspondence between new and old discriminants is not one
10488 -- to one: one new discriminant can constrain several old ones. In
10489 -- that case, scan sequentially the stored_constraint, the list of
10490 -- discriminants of the parents, and the constraints.
10491 -- Previous code checked for the present of the Stored_Constraint
10492 -- list for the derived type, but did not use it at all. Should it
10493 -- be present when the component is a discriminated task type?
10495 if Is_Derived_Type (Typ)
10496 and then Scope (Entity (Discrim)) = Etype (Typ)
10498 D := First_Discriminant (Etype (Typ));
10499 E := First_Elmt (Constraints);
10500 while Present (D) loop
10501 if D = Entity (Discrim) then
10505 Next_Discriminant (D);
10510 -- Something is wrong if we did not find the value
10512 raise Program_Error;
10513 end Get_Discr_Value;
10515 ---------------------
10516 -- Is_Discriminant --
10517 ---------------------
10519 function Is_Discriminant (Expr : Node_Id) return Boolean is
10520 Discrim_Scope : Entity_Id;
10523 if Denotes_Discriminant (Expr) then
10524 Discrim_Scope := Scope (Entity (Expr));
10526 -- Either we have a reference to one of Typ's discriminants,
10528 pragma Assert (Discrim_Scope = Typ
10530 -- or to the discriminants of the parent type, in the case
10531 -- of a derivation of a tagged type with variants.
10533 or else Discrim_Scope = Etype (Typ)
10534 or else Full_View (Discrim_Scope) = Etype (Typ)
10536 -- or same as above for the case where the discriminants
10537 -- were declared in Typ's private view.
10539 or else (Is_Private_Type (Discrim_Scope)
10540 and then Chars (Discrim_Scope) = Chars (Typ))
10542 -- or else we are deriving from the full view and the
10543 -- discriminant is declared in the private entity.
10545 or else (Is_Private_Type (Typ)
10546 and then Chars (Discrim_Scope) = Chars (Typ))
10548 -- Or we are constrained the corresponding record of a
10549 -- synchronized type that completes a private declaration.
10551 or else (Is_Concurrent_Record_Type (Typ)
10553 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
10555 -- or we have a class-wide type, in which case make sure the
10556 -- discriminant found belongs to the root type.
10558 or else (Is_Class_Wide_Type (Typ)
10559 and then Etype (Typ) = Discrim_Scope));
10564 -- In all other cases we have something wrong
10567 end Is_Discriminant;
10569 -- Start of processing for Constrain_Component_Type
10572 if Nkind (Parent (Comp)) = N_Component_Declaration
10573 and then Comes_From_Source (Parent (Comp))
10574 and then Comes_From_Source
10575 (Subtype_Indication (Component_Definition (Parent (Comp))))
10578 (Subtype_Indication (Component_Definition (Parent (Comp))))
10580 return Compon_Type;
10582 elsif Is_Array_Type (Compon_Type) then
10583 return Build_Constrained_Array_Type (Compon_Type);
10585 elsif Has_Discriminants (Compon_Type) then
10586 return Build_Constrained_Discriminated_Type (Compon_Type);
10588 elsif Is_Access_Type (Compon_Type) then
10589 return Build_Constrained_Access_Type (Compon_Type);
10592 return Compon_Type;
10594 end Constrain_Component_Type;
10596 --------------------------
10597 -- Constrain_Concurrent --
10598 --------------------------
10600 -- For concurrent types, the associated record value type carries the same
10601 -- discriminants, so when we constrain a concurrent type, we must constrain
10602 -- the corresponding record type as well.
10604 procedure Constrain_Concurrent
10605 (Def_Id : in out Entity_Id;
10607 Related_Nod : Node_Id;
10608 Related_Id : Entity_Id;
10609 Suffix : Character)
10611 T_Ent : Entity_Id := Entity (Subtype_Mark (SI));
10615 if Ekind (T_Ent) in Access_Kind then
10616 T_Ent := Designated_Type (T_Ent);
10619 T_Val := Corresponding_Record_Type (T_Ent);
10621 if Present (T_Val) then
10623 if No (Def_Id) then
10624 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
10627 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
10629 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
10630 Set_Corresponding_Record_Type (Def_Id,
10631 Constrain_Corresponding_Record
10632 (Def_Id, T_Val, Related_Nod, Related_Id));
10635 -- If there is no associated record, expansion is disabled and this
10636 -- is a generic context. Create a subtype in any case, so that
10637 -- semantic analysis can proceed.
10639 if No (Def_Id) then
10640 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
10643 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
10645 end Constrain_Concurrent;
10647 ------------------------------------
10648 -- Constrain_Corresponding_Record --
10649 ------------------------------------
10651 function Constrain_Corresponding_Record
10652 (Prot_Subt : Entity_Id;
10653 Corr_Rec : Entity_Id;
10654 Related_Nod : Node_Id;
10655 Related_Id : Entity_Id) return Entity_Id
10657 T_Sub : constant Entity_Id :=
10658 Create_Itype (E_Record_Subtype, Related_Nod, Related_Id, 'V');
10661 Set_Etype (T_Sub, Corr_Rec);
10662 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
10663 Set_Is_Constrained (T_Sub, True);
10664 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
10665 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
10667 -- As elsewhere, we do not want to create a freeze node for this itype
10668 -- if it is created for a constrained component of an enclosing record
10669 -- because references to outer discriminants will appear out of scope.
10671 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
10672 Conditional_Delay (T_Sub, Corr_Rec);
10674 Set_Is_Frozen (T_Sub);
10677 if Has_Discriminants (Prot_Subt) then -- False only if errors.
10678 Set_Discriminant_Constraint
10679 (T_Sub, Discriminant_Constraint (Prot_Subt));
10680 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
10681 Create_Constrained_Components
10682 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
10685 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
10688 end Constrain_Corresponding_Record;
10690 -----------------------
10691 -- Constrain_Decimal --
10692 -----------------------
10694 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
10695 T : constant Entity_Id := Entity (Subtype_Mark (S));
10696 C : constant Node_Id := Constraint (S);
10697 Loc : constant Source_Ptr := Sloc (C);
10698 Range_Expr : Node_Id;
10699 Digits_Expr : Node_Id;
10704 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
10706 if Nkind (C) = N_Range_Constraint then
10707 Range_Expr := Range_Expression (C);
10708 Digits_Val := Digits_Value (T);
10711 pragma Assert (Nkind (C) = N_Digits_Constraint);
10712 Digits_Expr := Digits_Expression (C);
10713 Analyze_And_Resolve (Digits_Expr, Any_Integer);
10715 Check_Digits_Expression (Digits_Expr);
10716 Digits_Val := Expr_Value (Digits_Expr);
10718 if Digits_Val > Digits_Value (T) then
10720 ("digits expression is incompatible with subtype", C);
10721 Digits_Val := Digits_Value (T);
10724 if Present (Range_Constraint (C)) then
10725 Range_Expr := Range_Expression (Range_Constraint (C));
10727 Range_Expr := Empty;
10731 Set_Etype (Def_Id, Base_Type (T));
10732 Set_Size_Info (Def_Id, (T));
10733 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
10734 Set_Delta_Value (Def_Id, Delta_Value (T));
10735 Set_Scale_Value (Def_Id, Scale_Value (T));
10736 Set_Small_Value (Def_Id, Small_Value (T));
10737 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
10738 Set_Digits_Value (Def_Id, Digits_Val);
10740 -- Manufacture range from given digits value if no range present
10742 if No (Range_Expr) then
10743 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
10747 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
10749 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
10752 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
10753 Set_Discrete_RM_Size (Def_Id);
10755 -- Unconditionally delay the freeze, since we cannot set size
10756 -- information in all cases correctly until the freeze point.
10758 Set_Has_Delayed_Freeze (Def_Id);
10759 end Constrain_Decimal;
10761 ----------------------------------
10762 -- Constrain_Discriminated_Type --
10763 ----------------------------------
10765 procedure Constrain_Discriminated_Type
10766 (Def_Id : Entity_Id;
10768 Related_Nod : Node_Id;
10769 For_Access : Boolean := False)
10771 E : constant Entity_Id := Entity (Subtype_Mark (S));
10774 Elist : Elist_Id := New_Elmt_List;
10776 procedure Fixup_Bad_Constraint;
10777 -- This is called after finding a bad constraint, and after having
10778 -- posted an appropriate error message. The mission is to leave the
10779 -- entity T in as reasonable state as possible!
10781 --------------------------
10782 -- Fixup_Bad_Constraint --
10783 --------------------------
10785 procedure Fixup_Bad_Constraint is
10787 -- Set a reasonable Ekind for the entity. For an incomplete type,
10788 -- we can't do much, but for other types, we can set the proper
10789 -- corresponding subtype kind.
10791 if Ekind (T) = E_Incomplete_Type then
10792 Set_Ekind (Def_Id, Ekind (T));
10794 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
10797 -- Set Etype to the known type, to reduce chances of cascaded errors
10799 Set_Etype (Def_Id, E);
10800 Set_Error_Posted (Def_Id);
10801 end Fixup_Bad_Constraint;
10803 -- Start of processing for Constrain_Discriminated_Type
10806 C := Constraint (S);
10808 -- A discriminant constraint is only allowed in a subtype indication,
10809 -- after a subtype mark. This subtype mark must denote either a type
10810 -- with discriminants, or an access type whose designated type is a
10811 -- type with discriminants. A discriminant constraint specifies the
10812 -- values of these discriminants (RM 3.7.2(5)).
10814 T := Base_Type (Entity (Subtype_Mark (S)));
10816 if Ekind (T) in Access_Kind then
10817 T := Designated_Type (T);
10820 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal.
10821 -- Avoid generating an error for access-to-incomplete subtypes.
10823 if Ada_Version >= Ada_05
10824 and then Ekind (T) = E_Incomplete_Type
10825 and then Nkind (Parent (S)) = N_Subtype_Declaration
10826 and then not Is_Itype (Def_Id)
10828 -- A little sanity check, emit an error message if the type
10829 -- has discriminants to begin with. Type T may be a regular
10830 -- incomplete type or imported via a limited with clause.
10832 if Has_Discriminants (T)
10834 (From_With_Type (T)
10835 and then Present (Non_Limited_View (T))
10836 and then Nkind (Parent (Non_Limited_View (T))) =
10837 N_Full_Type_Declaration
10838 and then Present (Discriminant_Specifications
10839 (Parent (Non_Limited_View (T)))))
10842 ("(Ada 2005) incomplete subtype may not be constrained", C);
10844 Error_Msg_N ("invalid constraint: type has no discriminant", C);
10847 Fixup_Bad_Constraint;
10850 -- Check that the type has visible discriminants. The type may be
10851 -- a private type with unknown discriminants whose full view has
10852 -- discriminants which are invisible.
10854 elsif not Has_Discriminants (T)
10856 (Has_Unknown_Discriminants (T)
10857 and then Is_Private_Type (T))
10859 Error_Msg_N ("invalid constraint: type has no discriminant", C);
10860 Fixup_Bad_Constraint;
10863 elsif Is_Constrained (E)
10864 or else (Ekind (E) = E_Class_Wide_Subtype
10865 and then Present (Discriminant_Constraint (E)))
10867 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
10868 Fixup_Bad_Constraint;
10872 -- T may be an unconstrained subtype (e.g. a generic actual).
10873 -- Constraint applies to the base type.
10875 T := Base_Type (T);
10877 Elist := Build_Discriminant_Constraints (T, S);
10879 -- If the list returned was empty we had an error in building the
10880 -- discriminant constraint. We have also already signalled an error
10881 -- in the incomplete type case
10883 if Is_Empty_Elmt_List (Elist) then
10884 Fixup_Bad_Constraint;
10888 Build_Discriminated_Subtype (T, Def_Id, Elist, Related_Nod, For_Access);
10889 end Constrain_Discriminated_Type;
10891 ---------------------------
10892 -- Constrain_Enumeration --
10893 ---------------------------
10895 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
10896 T : constant Entity_Id := Entity (Subtype_Mark (S));
10897 C : constant Node_Id := Constraint (S);
10900 Set_Ekind (Def_Id, E_Enumeration_Subtype);
10902 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
10904 Set_Etype (Def_Id, Base_Type (T));
10905 Set_Size_Info (Def_Id, (T));
10906 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
10907 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
10909 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
10911 Set_Discrete_RM_Size (Def_Id);
10912 end Constrain_Enumeration;
10914 ----------------------
10915 -- Constrain_Float --
10916 ----------------------
10918 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
10919 T : constant Entity_Id := Entity (Subtype_Mark (S));
10925 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
10927 Set_Etype (Def_Id, Base_Type (T));
10928 Set_Size_Info (Def_Id, (T));
10929 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
10931 -- Process the constraint
10933 C := Constraint (S);
10935 -- Digits constraint present
10937 if Nkind (C) = N_Digits_Constraint then
10938 Check_Restriction (No_Obsolescent_Features, C);
10940 if Warn_On_Obsolescent_Feature then
10942 ("subtype digits constraint is an " &
10943 "obsolescent feature (RM J.3(8))?", C);
10946 D := Digits_Expression (C);
10947 Analyze_And_Resolve (D, Any_Integer);
10948 Check_Digits_Expression (D);
10949 Set_Digits_Value (Def_Id, Expr_Value (D));
10951 -- Check that digits value is in range. Obviously we can do this
10952 -- at compile time, but it is strictly a runtime check, and of
10953 -- course there is an ACVC test that checks this!
10955 if Digits_Value (Def_Id) > Digits_Value (T) then
10956 Error_Msg_Uint_1 := Digits_Value (T);
10957 Error_Msg_N ("?digits value is too large, maximum is ^", D);
10959 Make_Raise_Constraint_Error (Sloc (D),
10960 Reason => CE_Range_Check_Failed);
10961 Insert_Action (Declaration_Node (Def_Id), Rais);
10964 C := Range_Constraint (C);
10966 -- No digits constraint present
10969 Set_Digits_Value (Def_Id, Digits_Value (T));
10972 -- Range constraint present
10974 if Nkind (C) = N_Range_Constraint then
10975 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
10977 -- No range constraint present
10980 pragma Assert (No (C));
10981 Set_Scalar_Range (Def_Id, Scalar_Range (T));
10984 Set_Is_Constrained (Def_Id);
10985 end Constrain_Float;
10987 ---------------------
10988 -- Constrain_Index --
10989 ---------------------
10991 procedure Constrain_Index
10994 Related_Nod : Node_Id;
10995 Related_Id : Entity_Id;
10996 Suffix : Character;
10997 Suffix_Index : Nat)
10999 Def_Id : Entity_Id;
11000 R : Node_Id := Empty;
11001 T : constant Entity_Id := Etype (Index);
11004 if Nkind (S) = N_Range
11006 (Nkind (S) = N_Attribute_Reference
11007 and then Attribute_Name (S) = Name_Range)
11009 -- A Range attribute will transformed into N_Range by Resolve
11015 Process_Range_Expr_In_Decl (R, T, Empty_List);
11017 if not Error_Posted (S)
11019 (Nkind (S) /= N_Range
11020 or else not Covers (T, (Etype (Low_Bound (S))))
11021 or else not Covers (T, (Etype (High_Bound (S)))))
11023 if Base_Type (T) /= Any_Type
11024 and then Etype (Low_Bound (S)) /= Any_Type
11025 and then Etype (High_Bound (S)) /= Any_Type
11027 Error_Msg_N ("range expected", S);
11031 elsif Nkind (S) = N_Subtype_Indication then
11033 -- The parser has verified that this is a discrete indication
11035 Resolve_Discrete_Subtype_Indication (S, T);
11036 R := Range_Expression (Constraint (S));
11038 elsif Nkind (S) = N_Discriminant_Association then
11040 -- Syntactically valid in subtype indication
11042 Error_Msg_N ("invalid index constraint", S);
11043 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
11046 -- Subtype_Mark case, no anonymous subtypes to construct
11051 if Is_Entity_Name (S) then
11052 if not Is_Type (Entity (S)) then
11053 Error_Msg_N ("expect subtype mark for index constraint", S);
11055 elsif Base_Type (Entity (S)) /= Base_Type (T) then
11056 Wrong_Type (S, Base_Type (T));
11062 Error_Msg_N ("invalid index constraint", S);
11063 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
11069 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
11071 Set_Etype (Def_Id, Base_Type (T));
11073 if Is_Modular_Integer_Type (T) then
11074 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
11076 elsif Is_Integer_Type (T) then
11077 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
11080 Set_Ekind (Def_Id, E_Enumeration_Subtype);
11081 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
11082 Set_First_Literal (Def_Id, First_Literal (T));
11085 Set_Size_Info (Def_Id, (T));
11086 Set_RM_Size (Def_Id, RM_Size (T));
11087 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11089 Set_Scalar_Range (Def_Id, R);
11091 Set_Etype (S, Def_Id);
11092 Set_Discrete_RM_Size (Def_Id);
11093 end Constrain_Index;
11095 -----------------------
11096 -- Constrain_Integer --
11097 -----------------------
11099 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
11100 T : constant Entity_Id := Entity (Subtype_Mark (S));
11101 C : constant Node_Id := Constraint (S);
11104 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11106 if Is_Modular_Integer_Type (T) then
11107 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
11109 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
11112 Set_Etype (Def_Id, Base_Type (T));
11113 Set_Size_Info (Def_Id, (T));
11114 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11115 Set_Discrete_RM_Size (Def_Id);
11116 end Constrain_Integer;
11118 ------------------------------
11119 -- Constrain_Ordinary_Fixed --
11120 ------------------------------
11122 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
11123 T : constant Entity_Id := Entity (Subtype_Mark (S));
11129 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
11130 Set_Etype (Def_Id, Base_Type (T));
11131 Set_Size_Info (Def_Id, (T));
11132 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11133 Set_Small_Value (Def_Id, Small_Value (T));
11135 -- Process the constraint
11137 C := Constraint (S);
11139 -- Delta constraint present
11141 if Nkind (C) = N_Delta_Constraint then
11142 Check_Restriction (No_Obsolescent_Features, C);
11144 if Warn_On_Obsolescent_Feature then
11146 ("subtype delta constraint is an " &
11147 "obsolescent feature (RM J.3(7))?");
11150 D := Delta_Expression (C);
11151 Analyze_And_Resolve (D, Any_Real);
11152 Check_Delta_Expression (D);
11153 Set_Delta_Value (Def_Id, Expr_Value_R (D));
11155 -- Check that delta value is in range. Obviously we can do this
11156 -- at compile time, but it is strictly a runtime check, and of
11157 -- course there is an ACVC test that checks this!
11159 if Delta_Value (Def_Id) < Delta_Value (T) then
11160 Error_Msg_N ("?delta value is too small", D);
11162 Make_Raise_Constraint_Error (Sloc (D),
11163 Reason => CE_Range_Check_Failed);
11164 Insert_Action (Declaration_Node (Def_Id), Rais);
11167 C := Range_Constraint (C);
11169 -- No delta constraint present
11172 Set_Delta_Value (Def_Id, Delta_Value (T));
11175 -- Range constraint present
11177 if Nkind (C) = N_Range_Constraint then
11178 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11180 -- No range constraint present
11183 pragma Assert (No (C));
11184 Set_Scalar_Range (Def_Id, Scalar_Range (T));
11188 Set_Discrete_RM_Size (Def_Id);
11190 -- Unconditionally delay the freeze, since we cannot set size
11191 -- information in all cases correctly until the freeze point.
11193 Set_Has_Delayed_Freeze (Def_Id);
11194 end Constrain_Ordinary_Fixed;
11196 -----------------------
11197 -- Contain_Interface --
11198 -----------------------
11200 function Contain_Interface
11201 (Iface : Entity_Id;
11202 Ifaces : Elist_Id) return Boolean
11204 Iface_Elmt : Elmt_Id;
11207 if Present (Ifaces) then
11208 Iface_Elmt := First_Elmt (Ifaces);
11209 while Present (Iface_Elmt) loop
11210 if Node (Iface_Elmt) = Iface then
11214 Next_Elmt (Iface_Elmt);
11219 end Contain_Interface;
11221 ---------------------------
11222 -- Convert_Scalar_Bounds --
11223 ---------------------------
11225 procedure Convert_Scalar_Bounds
11227 Parent_Type : Entity_Id;
11228 Derived_Type : Entity_Id;
11231 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
11238 Lo := Build_Scalar_Bound
11239 (Type_Low_Bound (Derived_Type),
11240 Parent_Type, Implicit_Base);
11242 Hi := Build_Scalar_Bound
11243 (Type_High_Bound (Derived_Type),
11244 Parent_Type, Implicit_Base);
11251 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
11253 Set_Parent (Rng, N);
11254 Set_Scalar_Range (Derived_Type, Rng);
11256 -- Analyze the bounds
11258 Analyze_And_Resolve (Lo, Implicit_Base);
11259 Analyze_And_Resolve (Hi, Implicit_Base);
11261 -- Analyze the range itself, except that we do not analyze it if
11262 -- the bounds are real literals, and we have a fixed-point type.
11263 -- The reason for this is that we delay setting the bounds in this
11264 -- case till we know the final Small and Size values (see circuit
11265 -- in Freeze.Freeze_Fixed_Point_Type for further details).
11267 if Is_Fixed_Point_Type (Parent_Type)
11268 and then Nkind (Lo) = N_Real_Literal
11269 and then Nkind (Hi) = N_Real_Literal
11273 -- Here we do the analysis of the range
11275 -- Note: we do this manually, since if we do a normal Analyze and
11276 -- Resolve call, there are problems with the conversions used for
11277 -- the derived type range.
11280 Set_Etype (Rng, Implicit_Base);
11281 Set_Analyzed (Rng, True);
11283 end Convert_Scalar_Bounds;
11285 -------------------
11286 -- Copy_And_Swap --
11287 -------------------
11289 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
11291 -- Initialize new full declaration entity by copying the pertinent
11292 -- fields of the corresponding private declaration entity.
11294 -- We temporarily set Ekind to a value appropriate for a type to
11295 -- avoid assert failures in Einfo from checking for setting type
11296 -- attributes on something that is not a type. Ekind (Priv) is an
11297 -- appropriate choice, since it allowed the attributes to be set
11298 -- in the first place. This Ekind value will be modified later.
11300 Set_Ekind (Full, Ekind (Priv));
11302 -- Also set Etype temporarily to Any_Type, again, in the absence
11303 -- of errors, it will be properly reset, and if there are errors,
11304 -- then we want a value of Any_Type to remain.
11306 Set_Etype (Full, Any_Type);
11308 -- Now start copying attributes
11310 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
11312 if Has_Discriminants (Full) then
11313 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
11314 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
11317 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
11318 Set_Homonym (Full, Homonym (Priv));
11319 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
11320 Set_Is_Public (Full, Is_Public (Priv));
11321 Set_Is_Pure (Full, Is_Pure (Priv));
11322 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
11323 Set_Has_Pragma_Unmodified (Full, Has_Pragma_Unmodified (Priv));
11324 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
11325 Set_Has_Pragma_Unreferenced_Objects
11326 (Full, Has_Pragma_Unreferenced_Objects
11329 Conditional_Delay (Full, Priv);
11331 if Is_Tagged_Type (Full) then
11332 Set_Primitive_Operations (Full, Primitive_Operations (Priv));
11334 if Priv = Base_Type (Priv) then
11335 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
11339 Set_Is_Volatile (Full, Is_Volatile (Priv));
11340 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
11341 Set_Scope (Full, Scope (Priv));
11342 Set_Next_Entity (Full, Next_Entity (Priv));
11343 Set_First_Entity (Full, First_Entity (Priv));
11344 Set_Last_Entity (Full, Last_Entity (Priv));
11346 -- If access types have been recorded for later handling, keep them in
11347 -- the full view so that they get handled when the full view freeze
11348 -- node is expanded.
11350 if Present (Freeze_Node (Priv))
11351 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
11353 Ensure_Freeze_Node (Full);
11354 Set_Access_Types_To_Process
11355 (Freeze_Node (Full),
11356 Access_Types_To_Process (Freeze_Node (Priv)));
11359 -- Swap the two entities. Now Privat is the full type entity and Full is
11360 -- the private one. They will be swapped back at the end of the private
11361 -- part. This swapping ensures that the entity that is visible in the
11362 -- private part is the full declaration.
11364 Exchange_Entities (Priv, Full);
11365 Append_Entity (Full, Scope (Full));
11368 -------------------------------------
11369 -- Copy_Array_Base_Type_Attributes --
11370 -------------------------------------
11372 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
11374 Set_Component_Alignment (T1, Component_Alignment (T2));
11375 Set_Component_Type (T1, Component_Type (T2));
11376 Set_Component_Size (T1, Component_Size (T2));
11377 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
11378 Set_Finalize_Storage_Only (T1, Finalize_Storage_Only (T2));
11379 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
11380 Set_Has_Task (T1, Has_Task (T2));
11381 Set_Is_Packed (T1, Is_Packed (T2));
11382 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
11383 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
11384 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
11385 end Copy_Array_Base_Type_Attributes;
11387 -----------------------------------
11388 -- Copy_Array_Subtype_Attributes --
11389 -----------------------------------
11391 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
11393 Set_Size_Info (T1, T2);
11395 Set_First_Index (T1, First_Index (T2));
11396 Set_Is_Aliased (T1, Is_Aliased (T2));
11397 Set_Is_Atomic (T1, Is_Atomic (T2));
11398 Set_Is_Volatile (T1, Is_Volatile (T2));
11399 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
11400 Set_Is_Constrained (T1, Is_Constrained (T2));
11401 Set_Depends_On_Private (T1, Has_Private_Component (T2));
11402 Set_First_Rep_Item (T1, First_Rep_Item (T2));
11403 Set_Convention (T1, Convention (T2));
11404 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
11405 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
11406 Set_Packed_Array_Type (T1, Packed_Array_Type (T2));
11407 end Copy_Array_Subtype_Attributes;
11409 -----------------------------------
11410 -- Create_Constrained_Components --
11411 -----------------------------------
11413 procedure Create_Constrained_Components
11415 Decl_Node : Node_Id;
11417 Constraints : Elist_Id)
11419 Loc : constant Source_Ptr := Sloc (Subt);
11420 Comp_List : constant Elist_Id := New_Elmt_List;
11421 Parent_Type : constant Entity_Id := Etype (Typ);
11422 Assoc_List : constant List_Id := New_List;
11423 Discr_Val : Elmt_Id;
11427 Is_Static : Boolean := True;
11429 procedure Collect_Fixed_Components (Typ : Entity_Id);
11430 -- Collect parent type components that do not appear in a variant part
11432 procedure Create_All_Components;
11433 -- Iterate over Comp_List to create the components of the subtype
11435 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
11436 -- Creates a new component from Old_Compon, copying all the fields from
11437 -- it, including its Etype, inserts the new component in the Subt entity
11438 -- chain and returns the new component.
11440 function Is_Variant_Record (T : Entity_Id) return Boolean;
11441 -- If true, and discriminants are static, collect only components from
11442 -- variants selected by discriminant values.
11444 ------------------------------
11445 -- Collect_Fixed_Components --
11446 ------------------------------
11448 procedure Collect_Fixed_Components (Typ : Entity_Id) is
11450 -- Build association list for discriminants, and find components of the
11451 -- variant part selected by the values of the discriminants.
11453 Old_C := First_Discriminant (Typ);
11454 Discr_Val := First_Elmt (Constraints);
11455 while Present (Old_C) loop
11456 Append_To (Assoc_List,
11457 Make_Component_Association (Loc,
11458 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
11459 Expression => New_Copy (Node (Discr_Val))));
11461 Next_Elmt (Discr_Val);
11462 Next_Discriminant (Old_C);
11465 -- The tag, and the possible parent and controller components
11466 -- are unconditionally in the subtype.
11468 if Is_Tagged_Type (Typ)
11469 or else Has_Controlled_Component (Typ)
11471 Old_C := First_Component (Typ);
11472 while Present (Old_C) loop
11473 if Chars ((Old_C)) = Name_uTag
11474 or else Chars ((Old_C)) = Name_uParent
11475 or else Chars ((Old_C)) = Name_uController
11477 Append_Elmt (Old_C, Comp_List);
11480 Next_Component (Old_C);
11483 end Collect_Fixed_Components;
11485 ---------------------------
11486 -- Create_All_Components --
11487 ---------------------------
11489 procedure Create_All_Components is
11493 Comp := First_Elmt (Comp_List);
11494 while Present (Comp) loop
11495 Old_C := Node (Comp);
11496 New_C := Create_Component (Old_C);
11500 Constrain_Component_Type
11501 (Old_C, Subt, Decl_Node, Typ, Constraints));
11502 Set_Is_Public (New_C, Is_Public (Subt));
11506 end Create_All_Components;
11508 ----------------------
11509 -- Create_Component --
11510 ----------------------
11512 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
11513 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
11516 if Ekind (Old_Compon) = E_Discriminant
11517 and then Is_Completely_Hidden (Old_Compon)
11519 -- This is a shadow discriminant created for a discriminant of
11520 -- the parent type, which needs to be present in the subtype.
11521 -- Give the shadow discriminant an internal name that cannot
11522 -- conflict with that of visible components.
11524 Set_Chars (New_Compon, New_Internal_Name ('C'));
11527 -- Set the parent so we have a proper link for freezing etc. This is
11528 -- not a real parent pointer, since of course our parent does not own
11529 -- up to us and reference us, we are an illegitimate child of the
11530 -- original parent!
11532 Set_Parent (New_Compon, Parent (Old_Compon));
11534 -- If the old component's Esize was already determined and is a
11535 -- static value, then the new component simply inherits it. Otherwise
11536 -- the old component's size may require run-time determination, but
11537 -- the new component's size still might be statically determinable
11538 -- (if, for example it has a static constraint). In that case we want
11539 -- Layout_Type to recompute the component's size, so we reset its
11540 -- size and positional fields.
11542 if Frontend_Layout_On_Target
11543 and then not Known_Static_Esize (Old_Compon)
11545 Set_Esize (New_Compon, Uint_0);
11546 Init_Normalized_First_Bit (New_Compon);
11547 Init_Normalized_Position (New_Compon);
11548 Init_Normalized_Position_Max (New_Compon);
11551 -- We do not want this node marked as Comes_From_Source, since
11552 -- otherwise it would get first class status and a separate cross-
11553 -- reference line would be generated. Illegitimate children do not
11554 -- rate such recognition.
11556 Set_Comes_From_Source (New_Compon, False);
11558 -- But it is a real entity, and a birth certificate must be properly
11559 -- registered by entering it into the entity list.
11561 Enter_Name (New_Compon);
11564 end Create_Component;
11566 -----------------------
11567 -- Is_Variant_Record --
11568 -----------------------
11570 function Is_Variant_Record (T : Entity_Id) return Boolean is
11572 return Nkind (Parent (T)) = N_Full_Type_Declaration
11573 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
11574 and then Present (Component_List (Type_Definition (Parent (T))))
11577 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
11578 end Is_Variant_Record;
11580 -- Start of processing for Create_Constrained_Components
11583 pragma Assert (Subt /= Base_Type (Subt));
11584 pragma Assert (Typ = Base_Type (Typ));
11586 Set_First_Entity (Subt, Empty);
11587 Set_Last_Entity (Subt, Empty);
11589 -- Check whether constraint is fully static, in which case we can
11590 -- optimize the list of components.
11592 Discr_Val := First_Elmt (Constraints);
11593 while Present (Discr_Val) loop
11594 if not Is_OK_Static_Expression (Node (Discr_Val)) then
11595 Is_Static := False;
11599 Next_Elmt (Discr_Val);
11602 Set_Has_Static_Discriminants (Subt, Is_Static);
11606 -- Inherit the discriminants of the parent type
11608 Add_Discriminants : declare
11614 Old_C := First_Discriminant (Typ);
11616 while Present (Old_C) loop
11617 Num_Disc := Num_Disc + 1;
11618 New_C := Create_Component (Old_C);
11619 Set_Is_Public (New_C, Is_Public (Subt));
11620 Next_Discriminant (Old_C);
11623 -- For an untagged derived subtype, the number of discriminants may
11624 -- be smaller than the number of inherited discriminants, because
11625 -- several of them may be renamed by a single new discriminant or
11626 -- constrained. In this case, add the hidden discriminants back into
11627 -- the subtype, because they need to be present if the optimizer of
11628 -- the GCC 4.x back-end decides to break apart assignments between
11629 -- objects using the parent view into member-wise assignments.
11633 if Is_Derived_Type (Typ)
11634 and then not Is_Tagged_Type (Typ)
11636 Old_C := First_Stored_Discriminant (Typ);
11638 while Present (Old_C) loop
11639 Num_Gird := Num_Gird + 1;
11640 Next_Stored_Discriminant (Old_C);
11644 if Num_Gird > Num_Disc then
11646 -- Find out multiple uses of new discriminants, and add hidden
11647 -- components for the extra renamed discriminants. We recognize
11648 -- multiple uses through the Corresponding_Discriminant of a
11649 -- new discriminant: if it constrains several old discriminants,
11650 -- this field points to the last one in the parent type. The
11651 -- stored discriminants of the derived type have the same name
11652 -- as those of the parent.
11656 New_Discr : Entity_Id;
11657 Old_Discr : Entity_Id;
11660 Constr := First_Elmt (Stored_Constraint (Typ));
11661 Old_Discr := First_Stored_Discriminant (Typ);
11662 while Present (Constr) loop
11663 if Is_Entity_Name (Node (Constr))
11664 and then Ekind (Entity (Node (Constr))) = E_Discriminant
11666 New_Discr := Entity (Node (Constr));
11668 if Chars (Corresponding_Discriminant (New_Discr)) /=
11671 -- The new discriminant has been used to rename a
11672 -- subsequent old discriminant. Introduce a shadow
11673 -- component for the current old discriminant.
11675 New_C := Create_Component (Old_Discr);
11676 Set_Original_Record_Component (New_C, Old_Discr);
11680 -- The constraint has eliminated the old discriminant.
11681 -- Introduce a shadow component.
11683 New_C := Create_Component (Old_Discr);
11684 Set_Original_Record_Component (New_C, Old_Discr);
11687 Next_Elmt (Constr);
11688 Next_Stored_Discriminant (Old_Discr);
11692 end Add_Discriminants;
11695 and then Is_Variant_Record (Typ)
11697 Collect_Fixed_Components (Typ);
11699 Gather_Components (
11701 Component_List (Type_Definition (Parent (Typ))),
11702 Governed_By => Assoc_List,
11704 Report_Errors => Errors);
11705 pragma Assert (not Errors);
11707 Create_All_Components;
11709 -- If the subtype declaration is created for a tagged type derivation
11710 -- with constraints, we retrieve the record definition of the parent
11711 -- type to select the components of the proper variant.
11714 and then Is_Tagged_Type (Typ)
11715 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
11717 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
11718 and then Is_Variant_Record (Parent_Type)
11720 Collect_Fixed_Components (Typ);
11722 Gather_Components (
11724 Component_List (Type_Definition (Parent (Parent_Type))),
11725 Governed_By => Assoc_List,
11727 Report_Errors => Errors);
11728 pragma Assert (not Errors);
11730 -- If the tagged derivation has a type extension, collect all the
11731 -- new components therein.
11734 (Record_Extension_Part (Type_Definition (Parent (Typ))))
11736 Old_C := First_Component (Typ);
11737 while Present (Old_C) loop
11738 if Original_Record_Component (Old_C) = Old_C
11739 and then Chars (Old_C) /= Name_uTag
11740 and then Chars (Old_C) /= Name_uParent
11741 and then Chars (Old_C) /= Name_uController
11743 Append_Elmt (Old_C, Comp_List);
11746 Next_Component (Old_C);
11750 Create_All_Components;
11753 -- If discriminants are not static, or if this is a multi-level type
11754 -- extension, we have to include all components of the parent type.
11756 Old_C := First_Component (Typ);
11757 while Present (Old_C) loop
11758 New_C := Create_Component (Old_C);
11762 Constrain_Component_Type
11763 (Old_C, Subt, Decl_Node, Typ, Constraints));
11764 Set_Is_Public (New_C, Is_Public (Subt));
11766 Next_Component (Old_C);
11771 end Create_Constrained_Components;
11773 ------------------------------------------
11774 -- Decimal_Fixed_Point_Type_Declaration --
11775 ------------------------------------------
11777 procedure Decimal_Fixed_Point_Type_Declaration
11781 Loc : constant Source_Ptr := Sloc (Def);
11782 Digs_Expr : constant Node_Id := Digits_Expression (Def);
11783 Delta_Expr : constant Node_Id := Delta_Expression (Def);
11784 Implicit_Base : Entity_Id;
11791 Check_Restriction (No_Fixed_Point, Def);
11793 -- Create implicit base type
11796 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
11797 Set_Etype (Implicit_Base, Implicit_Base);
11799 -- Analyze and process delta expression
11801 Analyze_And_Resolve (Delta_Expr, Universal_Real);
11803 Check_Delta_Expression (Delta_Expr);
11804 Delta_Val := Expr_Value_R (Delta_Expr);
11806 -- Check delta is power of 10, and determine scale value from it
11812 Scale_Val := Uint_0;
11815 if Val < Ureal_1 then
11816 while Val < Ureal_1 loop
11817 Val := Val * Ureal_10;
11818 Scale_Val := Scale_Val + 1;
11821 if Scale_Val > 18 then
11822 Error_Msg_N ("scale exceeds maximum value of 18", Def);
11823 Scale_Val := UI_From_Int (+18);
11827 while Val > Ureal_1 loop
11828 Val := Val / Ureal_10;
11829 Scale_Val := Scale_Val - 1;
11832 if Scale_Val < -18 then
11833 Error_Msg_N ("scale is less than minimum value of -18", Def);
11834 Scale_Val := UI_From_Int (-18);
11838 if Val /= Ureal_1 then
11839 Error_Msg_N ("delta expression must be a power of 10", Def);
11840 Delta_Val := Ureal_10 ** (-Scale_Val);
11844 -- Set delta, scale and small (small = delta for decimal type)
11846 Set_Delta_Value (Implicit_Base, Delta_Val);
11847 Set_Scale_Value (Implicit_Base, Scale_Val);
11848 Set_Small_Value (Implicit_Base, Delta_Val);
11850 -- Analyze and process digits expression
11852 Analyze_And_Resolve (Digs_Expr, Any_Integer);
11853 Check_Digits_Expression (Digs_Expr);
11854 Digs_Val := Expr_Value (Digs_Expr);
11856 if Digs_Val > 18 then
11857 Digs_Val := UI_From_Int (+18);
11858 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
11861 Set_Digits_Value (Implicit_Base, Digs_Val);
11862 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
11864 -- Set range of base type from digits value for now. This will be
11865 -- expanded to represent the true underlying base range by Freeze.
11867 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
11869 -- Note: We leave size as zero for now, size will be set at freeze
11870 -- time. We have to do this for ordinary fixed-point, because the size
11871 -- depends on the specified small, and we might as well do the same for
11872 -- decimal fixed-point.
11874 pragma Assert (Esize (Implicit_Base) = Uint_0);
11876 -- If there are bounds given in the declaration use them as the
11877 -- bounds of the first named subtype.
11879 if Present (Real_Range_Specification (Def)) then
11881 RRS : constant Node_Id := Real_Range_Specification (Def);
11882 Low : constant Node_Id := Low_Bound (RRS);
11883 High : constant Node_Id := High_Bound (RRS);
11888 Analyze_And_Resolve (Low, Any_Real);
11889 Analyze_And_Resolve (High, Any_Real);
11890 Check_Real_Bound (Low);
11891 Check_Real_Bound (High);
11892 Low_Val := Expr_Value_R (Low);
11893 High_Val := Expr_Value_R (High);
11895 if Low_Val < (-Bound_Val) then
11897 ("range low bound too small for digits value", Low);
11898 Low_Val := -Bound_Val;
11901 if High_Val > Bound_Val then
11903 ("range high bound too large for digits value", High);
11904 High_Val := Bound_Val;
11907 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
11910 -- If no explicit range, use range that corresponds to given
11911 -- digits value. This will end up as the final range for the
11915 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
11918 -- Complete entity for first subtype
11920 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
11921 Set_Etype (T, Implicit_Base);
11922 Set_Size_Info (T, Implicit_Base);
11923 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
11924 Set_Digits_Value (T, Digs_Val);
11925 Set_Delta_Value (T, Delta_Val);
11926 Set_Small_Value (T, Delta_Val);
11927 Set_Scale_Value (T, Scale_Val);
11928 Set_Is_Constrained (T);
11929 end Decimal_Fixed_Point_Type_Declaration;
11931 -----------------------------------
11932 -- Derive_Progenitor_Subprograms --
11933 -----------------------------------
11935 procedure Derive_Progenitor_Subprograms
11936 (Parent_Type : Entity_Id;
11937 Tagged_Type : Entity_Id)
11942 Iface_Elmt : Elmt_Id;
11943 Iface_Subp : Entity_Id;
11944 New_Subp : Entity_Id := Empty;
11945 Prim_Elmt : Elmt_Id;
11950 pragma Assert (Ada_Version >= Ada_05
11951 and then Is_Record_Type (Tagged_Type)
11952 and then Is_Tagged_Type (Tagged_Type)
11953 and then Has_Interfaces (Tagged_Type));
11955 -- Step 1: Transfer to the full-view primitives associated with the
11956 -- partial-view that cover interface primitives. Conceptually this
11957 -- work should be done later by Process_Full_View; done here to
11958 -- simplify its implementation at later stages. It can be safely
11959 -- done here because interfaces must be visible in the partial and
11960 -- private view (RM 7.3(7.3/2)).
11962 -- Small optimization: This work is only required if the parent is
11963 -- abstract. If the tagged type is not abstract, it cannot have
11964 -- abstract primitives (the only entities in the list of primitives of
11965 -- non-abstract tagged types that can reference abstract primitives
11966 -- through its Alias attribute are the internal entities that have
11967 -- attribute Interface_Alias, and these entities are generated later
11968 -- by Freeze_Record_Type).
11970 if In_Private_Part (Current_Scope)
11971 and then Is_Abstract_Type (Parent_Type)
11973 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
11974 while Present (Elmt) loop
11975 Subp := Node (Elmt);
11977 -- At this stage it is not possible to have entities in the list
11978 -- of primitives that have attribute Interface_Alias
11980 pragma Assert (No (Interface_Alias (Subp)));
11982 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
11984 if Is_Interface (Typ) then
11985 E := Find_Primitive_Covering_Interface
11986 (Tagged_Type => Tagged_Type,
11987 Iface_Prim => Subp);
11990 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
11992 Replace_Elmt (Elmt, E);
11993 Remove_Homonym (Subp);
12001 -- Step 2: Add primitives of progenitors that are not implemented by
12002 -- parents of Tagged_Type
12004 if Present (Interfaces (Base_Type (Tagged_Type))) then
12005 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
12006 while Present (Iface_Elmt) loop
12007 Iface := Node (Iface_Elmt);
12009 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
12010 while Present (Prim_Elmt) loop
12011 Iface_Subp := Node (Prim_Elmt);
12013 -- Exclude derivation of predefined primitives except those
12014 -- that come from source. Required to catch declarations of
12015 -- equality operators of interfaces. For example:
12017 -- type Iface is interface;
12018 -- function "=" (Left, Right : Iface) return Boolean;
12020 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
12021 or else Comes_From_Source (Iface_Subp)
12023 E := Find_Primitive_Covering_Interface
12024 (Tagged_Type => Tagged_Type,
12025 Iface_Prim => Iface_Subp);
12027 -- If not found we derive a new primitive leaving its alias
12028 -- attribute referencing the interface primitive
12032 (New_Subp, Iface_Subp, Tagged_Type, Iface);
12034 -- Propagate to the full view interface entities associated
12035 -- with the partial view
12037 elsif In_Private_Part (Current_Scope)
12038 and then Present (Alias (E))
12039 and then Alias (E) = Iface_Subp
12041 List_Containing (Parent (E)) /=
12042 Private_Declarations
12044 (Unit_Declaration_Node (Current_Scope)))
12046 Append_Elmt (E, Primitive_Operations (Tagged_Type));
12050 Next_Elmt (Prim_Elmt);
12053 Next_Elmt (Iface_Elmt);
12056 end Derive_Progenitor_Subprograms;
12058 -----------------------
12059 -- Derive_Subprogram --
12060 -----------------------
12062 procedure Derive_Subprogram
12063 (New_Subp : in out Entity_Id;
12064 Parent_Subp : Entity_Id;
12065 Derived_Type : Entity_Id;
12066 Parent_Type : Entity_Id;
12067 Actual_Subp : Entity_Id := Empty)
12069 Formal : Entity_Id;
12070 -- Formal parameter of parent primitive operation
12072 Formal_Of_Actual : Entity_Id;
12073 -- Formal parameter of actual operation, when the derivation is to
12074 -- create a renaming for a primitive operation of an actual in an
12077 New_Formal : Entity_Id;
12078 -- Formal of inherited operation
12080 Visible_Subp : Entity_Id := Parent_Subp;
12082 function Is_Private_Overriding return Boolean;
12083 -- If Subp is a private overriding of a visible operation, the inherited
12084 -- operation derives from the overridden op (even though its body is the
12085 -- overriding one) and the inherited operation is visible now. See
12086 -- sem_disp to see the full details of the handling of the overridden
12087 -- subprogram, which is removed from the list of primitive operations of
12088 -- the type. The overridden subprogram is saved locally in Visible_Subp,
12089 -- and used to diagnose abstract operations that need overriding in the
12092 procedure Replace_Type (Id, New_Id : Entity_Id);
12093 -- When the type is an anonymous access type, create a new access type
12094 -- designating the derived type.
12096 procedure Set_Derived_Name;
12097 -- This procedure sets the appropriate Chars name for New_Subp. This
12098 -- is normally just a copy of the parent name. An exception arises for
12099 -- type support subprograms, where the name is changed to reflect the
12100 -- name of the derived type, e.g. if type foo is derived from type bar,
12101 -- then a procedure barDA is derived with a name fooDA.
12103 ---------------------------
12104 -- Is_Private_Overriding --
12105 ---------------------------
12107 function Is_Private_Overriding return Boolean is
12111 -- If the parent is not a dispatching operation there is no
12112 -- need to investigate overridings
12114 if not Is_Dispatching_Operation (Parent_Subp) then
12118 -- The visible operation that is overridden is a homonym of the
12119 -- parent subprogram. We scan the homonym chain to find the one
12120 -- whose alias is the subprogram we are deriving.
12122 Prev := Current_Entity (Parent_Subp);
12123 while Present (Prev) loop
12124 if Ekind (Prev) = Ekind (Parent_Subp)
12125 and then Alias (Prev) = Parent_Subp
12126 and then Scope (Parent_Subp) = Scope (Prev)
12127 and then not Is_Hidden (Prev)
12129 Visible_Subp := Prev;
12133 Prev := Homonym (Prev);
12137 end Is_Private_Overriding;
12143 procedure Replace_Type (Id, New_Id : Entity_Id) is
12144 Acc_Type : Entity_Id;
12145 Par : constant Node_Id := Parent (Derived_Type);
12148 -- When the type is an anonymous access type, create a new access
12149 -- type designating the derived type. This itype must be elaborated
12150 -- at the point of the derivation, not on subsequent calls that may
12151 -- be out of the proper scope for Gigi, so we insert a reference to
12152 -- it after the derivation.
12154 if Ekind (Etype (Id)) = E_Anonymous_Access_Type then
12156 Desig_Typ : Entity_Id := Designated_Type (Etype (Id));
12159 if Ekind (Desig_Typ) = E_Record_Type_With_Private
12160 and then Present (Full_View (Desig_Typ))
12161 and then not Is_Private_Type (Parent_Type)
12163 Desig_Typ := Full_View (Desig_Typ);
12166 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
12168 -- Ada 2005 (AI-251): Handle also derivations of abstract
12169 -- interface primitives.
12171 or else (Is_Interface (Desig_Typ)
12172 and then not Is_Class_Wide_Type (Desig_Typ))
12174 Acc_Type := New_Copy (Etype (Id));
12175 Set_Etype (Acc_Type, Acc_Type);
12176 Set_Scope (Acc_Type, New_Subp);
12178 -- Compute size of anonymous access type
12180 if Is_Array_Type (Desig_Typ)
12181 and then not Is_Constrained (Desig_Typ)
12183 Init_Size (Acc_Type, 2 * System_Address_Size);
12185 Init_Size (Acc_Type, System_Address_Size);
12188 Init_Alignment (Acc_Type);
12189 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
12191 Set_Etype (New_Id, Acc_Type);
12192 Set_Scope (New_Id, New_Subp);
12194 -- Create a reference to it
12195 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
12198 Set_Etype (New_Id, Etype (Id));
12202 elsif Base_Type (Etype (Id)) = Base_Type (Parent_Type)
12204 (Ekind (Etype (Id)) = E_Record_Type_With_Private
12205 and then Present (Full_View (Etype (Id)))
12207 Base_Type (Full_View (Etype (Id))) = Base_Type (Parent_Type))
12209 -- Constraint checks on formals are generated during expansion,
12210 -- based on the signature of the original subprogram. The bounds
12211 -- of the derived type are not relevant, and thus we can use
12212 -- the base type for the formals. However, the return type may be
12213 -- used in a context that requires that the proper static bounds
12214 -- be used (a case statement, for example) and for those cases
12215 -- we must use the derived type (first subtype), not its base.
12217 -- If the derived_type_definition has no constraints, we know that
12218 -- the derived type has the same constraints as the first subtype
12219 -- of the parent, and we can also use it rather than its base,
12220 -- which can lead to more efficient code.
12222 if Etype (Id) = Parent_Type then
12223 if Is_Scalar_Type (Parent_Type)
12225 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
12227 Set_Etype (New_Id, Derived_Type);
12229 elsif Nkind (Par) = N_Full_Type_Declaration
12231 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
12234 (Subtype_Indication (Type_Definition (Par)))
12236 Set_Etype (New_Id, Derived_Type);
12239 Set_Etype (New_Id, Base_Type (Derived_Type));
12243 Set_Etype (New_Id, Base_Type (Derived_Type));
12246 -- Ada 2005 (AI-251): Handle derivations of abstract interface
12249 elsif Is_Interface (Etype (Id))
12250 and then not Is_Class_Wide_Type (Etype (Id))
12251 and then Is_Progenitor (Etype (Id), Derived_Type)
12253 Set_Etype (New_Id, Derived_Type);
12256 Set_Etype (New_Id, Etype (Id));
12260 ----------------------
12261 -- Set_Derived_Name --
12262 ----------------------
12264 procedure Set_Derived_Name is
12265 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
12267 if Nm = TSS_Null then
12268 Set_Chars (New_Subp, Chars (Parent_Subp));
12270 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
12272 end Set_Derived_Name;
12276 Parent_Overrides_Interface_Primitive : Boolean := False;
12278 -- Start of processing for Derive_Subprogram
12282 New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
12283 Set_Ekind (New_Subp, Ekind (Parent_Subp));
12285 -- Check whether the parent overrides an interface primitive
12287 if Is_Overriding_Operation (Parent_Subp) then
12289 E : Entity_Id := Parent_Subp;
12291 while Present (Overridden_Operation (E)) loop
12292 E := Ultimate_Alias (Overridden_Operation (E));
12295 Parent_Overrides_Interface_Primitive :=
12296 Is_Dispatching_Operation (E)
12297 and then Present (Find_Dispatching_Type (E))
12298 and then Is_Interface (Find_Dispatching_Type (E));
12302 -- Check whether the inherited subprogram is a private operation that
12303 -- should be inherited but not yet made visible. Such subprograms can
12304 -- become visible at a later point (e.g., the private part of a public
12305 -- child unit) via Declare_Inherited_Private_Subprograms. If the
12306 -- following predicate is true, then this is not such a private
12307 -- operation and the subprogram simply inherits the name of the parent
12308 -- subprogram. Note the special check for the names of controlled
12309 -- operations, which are currently exempted from being inherited with
12310 -- a hidden name because they must be findable for generation of
12311 -- implicit run-time calls.
12313 if not Is_Hidden (Parent_Subp)
12314 or else Is_Internal (Parent_Subp)
12315 or else Is_Private_Overriding
12316 or else Is_Internal_Name (Chars (Parent_Subp))
12317 or else Chars (Parent_Subp) = Name_Initialize
12318 or else Chars (Parent_Subp) = Name_Adjust
12319 or else Chars (Parent_Subp) = Name_Finalize
12323 -- An inherited dispatching equality will be overridden by an internally
12324 -- generated one, or by an explicit one, so preserve its name and thus
12325 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
12326 -- private operation it may become invisible if the full view has
12327 -- progenitors, and the dispatch table will be malformed.
12328 -- We check that the type is limited to handle the anomalous declaration
12329 -- of Limited_Controlled, which is derived from a non-limited type, and
12330 -- which is handled specially elsewhere as well.
12332 elsif Chars (Parent_Subp) = Name_Op_Eq
12333 and then Is_Dispatching_Operation (Parent_Subp)
12334 and then Etype (Parent_Subp) = Standard_Boolean
12335 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
12337 Etype (First_Formal (Parent_Subp)) =
12338 Etype (Next_Formal (First_Formal (Parent_Subp)))
12342 -- If parent is hidden, this can be a regular derivation if the
12343 -- parent is immediately visible in a non-instantiating context,
12344 -- or if we are in the private part of an instance. This test
12345 -- should still be refined ???
12347 -- The test for In_Instance_Not_Visible avoids inheriting the derived
12348 -- operation as a non-visible operation in cases where the parent
12349 -- subprogram might not be visible now, but was visible within the
12350 -- original generic, so it would be wrong to make the inherited
12351 -- subprogram non-visible now. (Not clear if this test is fully
12352 -- correct; are there any cases where we should declare the inherited
12353 -- operation as not visible to avoid it being overridden, e.g., when
12354 -- the parent type is a generic actual with private primitives ???)
12356 -- (they should be treated the same as other private inherited
12357 -- subprograms, but it's not clear how to do this cleanly). ???
12359 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
12360 and then Is_Immediately_Visible (Parent_Subp)
12361 and then not In_Instance)
12362 or else In_Instance_Not_Visible
12366 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
12367 -- overrides an interface primitive because interface primitives
12368 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
12370 elsif Parent_Overrides_Interface_Primitive then
12373 -- Otherwise, the type is inheriting a private operation, so enter
12374 -- it with a special name so it can't be overridden.
12377 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
12380 Set_Parent (New_Subp, Parent (Derived_Type));
12382 if Present (Actual_Subp) then
12383 Replace_Type (Actual_Subp, New_Subp);
12385 Replace_Type (Parent_Subp, New_Subp);
12388 Conditional_Delay (New_Subp, Parent_Subp);
12390 -- If we are creating a renaming for a primitive operation of an
12391 -- actual of a generic derived type, we must examine the signature
12392 -- of the actual primitive, not that of the generic formal, which for
12393 -- example may be an interface. However the name and initial value
12394 -- of the inherited operation are those of the formal primitive.
12396 Formal := First_Formal (Parent_Subp);
12398 if Present (Actual_Subp) then
12399 Formal_Of_Actual := First_Formal (Actual_Subp);
12401 Formal_Of_Actual := Empty;
12404 while Present (Formal) loop
12405 New_Formal := New_Copy (Formal);
12407 -- Normally we do not go copying parents, but in the case of
12408 -- formals, we need to link up to the declaration (which is the
12409 -- parameter specification), and it is fine to link up to the
12410 -- original formal's parameter specification in this case.
12412 Set_Parent (New_Formal, Parent (Formal));
12413 Append_Entity (New_Formal, New_Subp);
12415 if Present (Formal_Of_Actual) then
12416 Replace_Type (Formal_Of_Actual, New_Formal);
12417 Next_Formal (Formal_Of_Actual);
12419 Replace_Type (Formal, New_Formal);
12422 Next_Formal (Formal);
12425 -- If this derivation corresponds to a tagged generic actual, then
12426 -- primitive operations rename those of the actual. Otherwise the
12427 -- primitive operations rename those of the parent type, If the parent
12428 -- renames an intrinsic operator, so does the new subprogram. We except
12429 -- concatenation, which is always properly typed, and does not get
12430 -- expanded as other intrinsic operations.
12432 if No (Actual_Subp) then
12433 if Is_Intrinsic_Subprogram (Parent_Subp) then
12434 Set_Is_Intrinsic_Subprogram (New_Subp);
12436 if Present (Alias (Parent_Subp))
12437 and then Chars (Parent_Subp) /= Name_Op_Concat
12439 Set_Alias (New_Subp, Alias (Parent_Subp));
12441 Set_Alias (New_Subp, Parent_Subp);
12445 Set_Alias (New_Subp, Parent_Subp);
12449 Set_Alias (New_Subp, Actual_Subp);
12452 -- Derived subprograms of a tagged type must inherit the convention
12453 -- of the parent subprogram (a requirement of AI-117). Derived
12454 -- subprograms of untagged types simply get convention Ada by default.
12456 if Is_Tagged_Type (Derived_Type) then
12457 Set_Convention (New_Subp, Convention (Parent_Subp));
12460 -- Predefined controlled operations retain their name even if the parent
12461 -- is hidden (see above), but they are not primitive operations if the
12462 -- ancestor is not visible, for example if the parent is a private
12463 -- extension completed with a controlled extension. Note that a full
12464 -- type that is controlled can break privacy: the flag Is_Controlled is
12465 -- set on both views of the type.
12467 if Is_Controlled (Parent_Type)
12469 (Chars (Parent_Subp) = Name_Initialize
12470 or else Chars (Parent_Subp) = Name_Adjust
12471 or else Chars (Parent_Subp) = Name_Finalize)
12472 and then Is_Hidden (Parent_Subp)
12473 and then not Is_Visibly_Controlled (Parent_Type)
12475 Set_Is_Hidden (New_Subp);
12478 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
12479 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
12481 if Ekind (Parent_Subp) = E_Procedure then
12482 Set_Is_Valued_Procedure
12483 (New_Subp, Is_Valued_Procedure (Parent_Subp));
12486 -- No_Return must be inherited properly. If this is overridden in the
12487 -- case of a dispatching operation, then a check is made in Sem_Disp
12488 -- that the overriding operation is also No_Return (no such check is
12489 -- required for the case of non-dispatching operation.
12491 Set_No_Return (New_Subp, No_Return (Parent_Subp));
12493 -- A derived function with a controlling result is abstract. If the
12494 -- Derived_Type is a nonabstract formal generic derived type, then
12495 -- inherited operations are not abstract: the required check is done at
12496 -- instantiation time. If the derivation is for a generic actual, the
12497 -- function is not abstract unless the actual is.
12499 if Is_Generic_Type (Derived_Type)
12500 and then not Is_Abstract_Type (Derived_Type)
12504 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
12505 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
12507 elsif Ada_Version >= Ada_05
12508 and then (Is_Abstract_Subprogram (Alias (New_Subp))
12509 or else (Is_Tagged_Type (Derived_Type)
12510 and then Etype (New_Subp) = Derived_Type
12511 and then not Is_Null_Extension (Derived_Type))
12512 or else (Is_Tagged_Type (Derived_Type)
12513 and then Ekind (Etype (New_Subp)) =
12514 E_Anonymous_Access_Type
12515 and then Designated_Type (Etype (New_Subp)) =
12517 and then not Is_Null_Extension (Derived_Type)))
12518 and then No (Actual_Subp)
12520 if not Is_Tagged_Type (Derived_Type)
12521 or else Is_Abstract_Type (Derived_Type)
12522 or else Is_Abstract_Subprogram (Alias (New_Subp))
12524 Set_Is_Abstract_Subprogram (New_Subp);
12526 Set_Requires_Overriding (New_Subp);
12529 elsif Ada_Version < Ada_05
12530 and then (Is_Abstract_Subprogram (Alias (New_Subp))
12531 or else (Is_Tagged_Type (Derived_Type)
12532 and then Etype (New_Subp) = Derived_Type
12533 and then No (Actual_Subp)))
12535 Set_Is_Abstract_Subprogram (New_Subp);
12537 -- Finally, if the parent type is abstract we must verify that all
12538 -- inherited operations are either non-abstract or overridden, or that
12539 -- the derived type itself is abstract (this check is performed at the
12540 -- end of a package declaration, in Check_Abstract_Overriding). A
12541 -- private overriding in the parent type will not be visible in the
12542 -- derivation if we are not in an inner package or in a child unit of
12543 -- the parent type, in which case the abstractness of the inherited
12544 -- operation is carried to the new subprogram.
12546 elsif Is_Abstract_Type (Parent_Type)
12547 and then not In_Open_Scopes (Scope (Parent_Type))
12548 and then Is_Private_Overriding
12549 and then Is_Abstract_Subprogram (Visible_Subp)
12551 if No (Actual_Subp) then
12552 Set_Alias (New_Subp, Visible_Subp);
12553 Set_Is_Abstract_Subprogram (New_Subp, True);
12556 -- If this is a derivation for an instance of a formal derived
12557 -- type, abstractness comes from the primitive operation of the
12558 -- actual, not from the operation inherited from the ancestor.
12560 Set_Is_Abstract_Subprogram
12561 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
12565 New_Overloaded_Entity (New_Subp, Derived_Type);
12567 -- Check for case of a derived subprogram for the instantiation of a
12568 -- formal derived tagged type, if so mark the subprogram as dispatching
12569 -- and inherit the dispatching attributes of the parent subprogram. The
12570 -- derived subprogram is effectively renaming of the actual subprogram,
12571 -- so it needs to have the same attributes as the actual.
12573 if Present (Actual_Subp)
12574 and then Is_Dispatching_Operation (Parent_Subp)
12576 Set_Is_Dispatching_Operation (New_Subp);
12578 if Present (DTC_Entity (Parent_Subp)) then
12579 Set_DTC_Entity (New_Subp, DTC_Entity (Parent_Subp));
12580 Set_DT_Position (New_Subp, DT_Position (Parent_Subp));
12584 -- Indicate that a derived subprogram does not require a body and that
12585 -- it does not require processing of default expressions.
12587 Set_Has_Completion (New_Subp);
12588 Set_Default_Expressions_Processed (New_Subp);
12590 if Ekind (New_Subp) = E_Function then
12591 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
12593 end Derive_Subprogram;
12595 ------------------------
12596 -- Derive_Subprograms --
12597 ------------------------
12599 procedure Derive_Subprograms
12600 (Parent_Type : Entity_Id;
12601 Derived_Type : Entity_Id;
12602 Generic_Actual : Entity_Id := Empty)
12604 Op_List : constant Elist_Id :=
12605 Collect_Primitive_Operations (Parent_Type);
12607 function Check_Derived_Type return Boolean;
12608 -- Check that all primitive inherited from Parent_Type are found in
12609 -- the list of primitives of Derived_Type exactly in the same order.
12611 function Check_Derived_Type return Boolean is
12615 New_Subp : Entity_Id;
12620 -- Traverse list of entities in the current scope searching for
12621 -- an incomplete type whose full-view is derived type
12623 E := First_Entity (Scope (Derived_Type));
12625 and then E /= Derived_Type
12627 if Ekind (E) = E_Incomplete_Type
12628 and then Present (Full_View (E))
12629 and then Full_View (E) = Derived_Type
12631 -- Disable this test if Derived_Type completes an incomplete
12632 -- type because in such case more primitives can be added
12633 -- later to the list of primitives of Derived_Type by routine
12634 -- Process_Incomplete_Dependents
12639 E := Next_Entity (E);
12642 List := Collect_Primitive_Operations (Derived_Type);
12643 Elmt := First_Elmt (List);
12645 Op_Elmt := First_Elmt (Op_List);
12646 while Present (Op_Elmt) loop
12647 Subp := Node (Op_Elmt);
12648 New_Subp := Node (Elmt);
12650 -- At this early stage Derived_Type has no entities with attribute
12651 -- Interface_Alias. In addition, such primitives are always
12652 -- located at the end of the list of primitives of Parent_Type.
12653 -- Therefore, if found we can safely stop processing pending
12656 exit when Present (Interface_Alias (Subp));
12658 -- Handle hidden entities
12660 if not Is_Predefined_Dispatching_Operation (Subp)
12661 and then Is_Hidden (Subp)
12663 if Present (New_Subp)
12664 and then Primitive_Names_Match (Subp, New_Subp)
12670 if not Present (New_Subp)
12671 or else Ekind (Subp) /= Ekind (New_Subp)
12672 or else not Primitive_Names_Match (Subp, New_Subp)
12680 Next_Elmt (Op_Elmt);
12684 end Check_Derived_Type;
12688 Alias_Subp : Entity_Id;
12689 Act_List : Elist_Id;
12690 Act_Elmt : Elmt_Id := No_Elmt;
12691 Act_Subp : Entity_Id := Empty;
12693 Need_Search : Boolean := False;
12694 New_Subp : Entity_Id := Empty;
12695 Parent_Base : Entity_Id;
12698 -- Start of processing for Derive_Subprograms
12701 if Ekind (Parent_Type) = E_Record_Type_With_Private
12702 and then Has_Discriminants (Parent_Type)
12703 and then Present (Full_View (Parent_Type))
12705 Parent_Base := Full_View (Parent_Type);
12707 Parent_Base := Parent_Type;
12710 if Present (Generic_Actual) then
12711 Act_List := Collect_Primitive_Operations (Generic_Actual);
12712 Act_Elmt := First_Elmt (Act_List);
12715 -- Derive primitives inherited from the parent. Note that if the generic
12716 -- actual is present, this is not really a type derivation, it is a
12717 -- completion within an instance.
12719 -- Case 1: Derived_Type does not implement interfaces
12721 if not Is_Tagged_Type (Derived_Type)
12722 or else (not Has_Interfaces (Derived_Type)
12723 and then not (Present (Generic_Actual)
12725 Has_Interfaces (Generic_Actual)))
12727 Elmt := First_Elmt (Op_List);
12728 while Present (Elmt) loop
12729 Subp := Node (Elmt);
12731 -- Literals are derived earlier in the process of building the
12732 -- derived type, and are skipped here.
12734 if Ekind (Subp) = E_Enumeration_Literal then
12737 -- The actual is a direct descendant and the common primitive
12738 -- operations appear in the same order.
12740 -- If the generic parent type is present, the derived type is an
12741 -- instance of a formal derived type, and within the instance its
12742 -- operations are those of the actual. We derive from the formal
12743 -- type but make the inherited operations aliases of the
12744 -- corresponding operations of the actual.
12748 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
12750 if Present (Act_Elmt) then
12751 Next_Elmt (Act_Elmt);
12758 -- Case 2: Derived_Type implements interfaces
12761 -- If the parent type has no predefined primitives we remove
12762 -- predefined primitives from the list of primitives of generic
12763 -- actual to simplify the complexity of this algorithm.
12765 if Present (Generic_Actual) then
12767 Has_Predefined_Primitives : Boolean := False;
12770 -- Check if the parent type has predefined primitives
12772 Elmt := First_Elmt (Op_List);
12773 while Present (Elmt) loop
12774 Subp := Node (Elmt);
12776 if Is_Predefined_Dispatching_Operation (Subp)
12777 and then not Comes_From_Source (Ultimate_Alias (Subp))
12779 Has_Predefined_Primitives := True;
12786 -- Remove predefined primitives of Generic_Actual. We must use
12787 -- an auxiliary list because in case of tagged types the value
12788 -- returned by Collect_Primitive_Operations is the value stored
12789 -- in its Primitive_Operations attribute (and we don't want to
12790 -- modify its current contents).
12792 if not Has_Predefined_Primitives then
12794 Aux_List : constant Elist_Id := New_Elmt_List;
12797 Elmt := First_Elmt (Act_List);
12798 while Present (Elmt) loop
12799 Subp := Node (Elmt);
12801 if not Is_Predefined_Dispatching_Operation (Subp)
12802 or else Comes_From_Source (Subp)
12804 Append_Elmt (Subp, Aux_List);
12810 Act_List := Aux_List;
12814 Act_Elmt := First_Elmt (Act_List);
12815 Act_Subp := Node (Act_Elmt);
12819 -- Stage 1: If the generic actual is not present we derive the
12820 -- primitives inherited from the parent type. If the generic parent
12821 -- type is present, the derived type is an instance of a formal
12822 -- derived type, and within the instance its operations are those of
12823 -- the actual. We derive from the formal type but make the inherited
12824 -- operations aliases of the corresponding operations of the actual.
12826 Elmt := First_Elmt (Op_List);
12827 while Present (Elmt) loop
12828 Subp := Node (Elmt);
12829 Alias_Subp := Ultimate_Alias (Subp);
12831 -- At this early stage Derived_Type has no entities with attribute
12832 -- Interface_Alias. In addition, such primitives are always
12833 -- located at the end of the list of primitives of Parent_Type.
12834 -- Therefore, if found we can safely stop processing pending
12837 exit when Present (Interface_Alias (Subp));
12839 -- If the generic actual is present find the corresponding
12840 -- operation in the generic actual. If the parent type is a
12841 -- direct ancestor of the derived type then, even if it is an
12842 -- interface, the operations are inherited from the primary
12843 -- dispatch table and are in the proper order. If we detect here
12844 -- that primitives are not in the same order we traverse the list
12845 -- of primitive operations of the actual to find the one that
12846 -- implements the interface primitive.
12850 (Present (Generic_Actual)
12851 and then Present (Act_Subp)
12852 and then not Primitive_Names_Match (Subp, Act_Subp))
12854 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual));
12856 -- Remember that we need searching for all pending primitives
12858 Need_Search := True;
12860 -- Handle entities associated with interface primitives
12862 if Present (Alias (Subp))
12863 and then Is_Interface (Find_Dispatching_Type (Alias (Subp)))
12864 and then not Is_Predefined_Dispatching_Operation (Subp)
12867 Find_Primitive_Covering_Interface
12868 (Tagged_Type => Generic_Actual,
12869 Iface_Prim => Subp);
12871 -- Handle predefined primitives plus the rest of user-defined
12875 Act_Elmt := First_Elmt (Act_List);
12876 while Present (Act_Elmt) loop
12877 Act_Subp := Node (Act_Elmt);
12879 exit when Primitive_Names_Match (Subp, Act_Subp)
12880 and then Type_Conformant
12882 Skip_Controlling_Formals => True)
12883 and then No (Interface_Alias (Act_Subp));
12885 Next_Elmt (Act_Elmt);
12890 -- Case 1: If the parent is a limited interface then it has the
12891 -- predefined primitives of synchronized interfaces. However, the
12892 -- actual type may be a non-limited type and hence it does not
12893 -- have such primitives.
12895 if Present (Generic_Actual)
12896 and then not Present (Act_Subp)
12897 and then Is_Limited_Interface (Parent_Base)
12898 and then Is_Predefined_Interface_Primitive (Subp)
12902 -- Case 2: Inherit entities associated with interfaces that
12903 -- were not covered by the parent type. We exclude here null
12904 -- interface primitives because they do not need special
12907 elsif Present (Alias (Subp))
12908 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
12910 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
12911 and then Null_Present (Parent (Alias_Subp)))
12914 (New_Subp => New_Subp,
12915 Parent_Subp => Alias_Subp,
12916 Derived_Type => Derived_Type,
12917 Parent_Type => Find_Dispatching_Type (Alias_Subp),
12918 Actual_Subp => Act_Subp);
12920 if No (Generic_Actual) then
12921 Set_Alias (New_Subp, Subp);
12924 -- Case 3: Common derivation
12928 (New_Subp => New_Subp,
12929 Parent_Subp => Subp,
12930 Derived_Type => Derived_Type,
12931 Parent_Type => Parent_Base,
12932 Actual_Subp => Act_Subp);
12935 -- No need to update Act_Elm if we must search for the
12936 -- corresponding operation in the generic actual
12939 and then Present (Act_Elmt)
12941 Next_Elmt (Act_Elmt);
12942 Act_Subp := Node (Act_Elmt);
12948 -- Inherit additional operations from progenitors. If the derived
12949 -- type is a generic actual, there are not new primitive operations
12950 -- for the type because it has those of the actual, and therefore
12951 -- nothing needs to be done. The renamings generated above are not
12952 -- primitive operations, and their purpose is simply to make the
12953 -- proper operations visible within an instantiation.
12955 if No (Generic_Actual) then
12956 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
12960 -- Final check: Direct descendants must have their primitives in the
12961 -- same order. We exclude from this test non-tagged types and instances
12962 -- of formal derived types. We skip this test if we have already
12963 -- reported serious errors in the sources.
12965 pragma Assert (not Is_Tagged_Type (Derived_Type)
12966 or else Present (Generic_Actual)
12967 or else Serious_Errors_Detected > 0
12968 or else Check_Derived_Type);
12969 end Derive_Subprograms;
12971 --------------------------------
12972 -- Derived_Standard_Character --
12973 --------------------------------
12975 procedure Derived_Standard_Character
12977 Parent_Type : Entity_Id;
12978 Derived_Type : Entity_Id)
12980 Loc : constant Source_Ptr := Sloc (N);
12981 Def : constant Node_Id := Type_Definition (N);
12982 Indic : constant Node_Id := Subtype_Indication (Def);
12983 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
12984 Implicit_Base : constant Entity_Id :=
12986 (E_Enumeration_Type, N, Derived_Type, 'B');
12992 Discard_Node (Process_Subtype (Indic, N));
12994 Set_Etype (Implicit_Base, Parent_Base);
12995 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
12996 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
12998 Set_Is_Character_Type (Implicit_Base, True);
12999 Set_Has_Delayed_Freeze (Implicit_Base);
13001 -- The bounds of the implicit base are the bounds of the parent base.
13002 -- Note that their type is the parent base.
13004 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
13005 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
13007 Set_Scalar_Range (Implicit_Base,
13010 High_Bound => Hi));
13012 Conditional_Delay (Derived_Type, Parent_Type);
13014 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
13015 Set_Etype (Derived_Type, Implicit_Base);
13016 Set_Size_Info (Derived_Type, Parent_Type);
13018 if Unknown_RM_Size (Derived_Type) then
13019 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
13022 Set_Is_Character_Type (Derived_Type, True);
13024 if Nkind (Indic) /= N_Subtype_Indication then
13026 -- If no explicit constraint, the bounds are those
13027 -- of the parent type.
13029 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
13030 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
13031 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
13034 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
13036 -- Because the implicit base is used in the conversion of the bounds, we
13037 -- have to freeze it now. This is similar to what is done for numeric
13038 -- types, and it equally suspicious, but otherwise a non-static bound
13039 -- will have a reference to an unfrozen type, which is rejected by Gigi
13040 -- (???). This requires specific care for definition of stream
13041 -- attributes. For details, see comments at the end of
13042 -- Build_Derived_Numeric_Type.
13044 Freeze_Before (N, Implicit_Base);
13045 end Derived_Standard_Character;
13047 ------------------------------
13048 -- Derived_Type_Declaration --
13049 ------------------------------
13051 procedure Derived_Type_Declaration
13054 Is_Completion : Boolean)
13056 Parent_Type : Entity_Id;
13058 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
13059 -- Check whether the parent type is a generic formal, or derives
13060 -- directly or indirectly from one.
13062 ------------------------
13063 -- Comes_From_Generic --
13064 ------------------------
13066 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
13068 if Is_Generic_Type (Typ) then
13071 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
13074 elsif Is_Private_Type (Typ)
13075 and then Present (Full_View (Typ))
13076 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
13080 elsif Is_Generic_Actual_Type (Typ) then
13086 end Comes_From_Generic;
13090 Def : constant Node_Id := Type_Definition (N);
13091 Iface_Def : Node_Id;
13092 Indic : constant Node_Id := Subtype_Indication (Def);
13093 Extension : constant Node_Id := Record_Extension_Part (Def);
13094 Parent_Node : Node_Id;
13095 Parent_Scope : Entity_Id;
13098 -- Start of processing for Derived_Type_Declaration
13101 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
13103 -- Ada 2005 (AI-251): In case of interface derivation check that the
13104 -- parent is also an interface.
13106 if Interface_Present (Def) then
13107 if not Is_Interface (Parent_Type) then
13108 Diagnose_Interface (Indic, Parent_Type);
13111 Parent_Node := Parent (Base_Type (Parent_Type));
13112 Iface_Def := Type_Definition (Parent_Node);
13114 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
13115 -- other limited interfaces.
13117 if Limited_Present (Def) then
13118 if Limited_Present (Iface_Def) then
13121 elsif Protected_Present (Iface_Def) then
13123 ("descendant of& must be declared"
13124 & " as a protected interface",
13127 elsif Synchronized_Present (Iface_Def) then
13129 ("descendant of& must be declared"
13130 & " as a synchronized interface",
13133 elsif Task_Present (Iface_Def) then
13135 ("descendant of& must be declared as a task interface",
13140 ("(Ada 2005) limited interface cannot "
13141 & "inherit from non-limited interface", Indic);
13144 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
13145 -- from non-limited or limited interfaces.
13147 elsif not Protected_Present (Def)
13148 and then not Synchronized_Present (Def)
13149 and then not Task_Present (Def)
13151 if Limited_Present (Iface_Def) then
13154 elsif Protected_Present (Iface_Def) then
13156 ("descendant of& must be declared"
13157 & " as a protected interface",
13160 elsif Synchronized_Present (Iface_Def) then
13162 ("descendant of& must be declared"
13163 & " as a synchronized interface",
13166 elsif Task_Present (Iface_Def) then
13168 ("descendant of& must be declared as a task interface",
13177 if Is_Tagged_Type (Parent_Type)
13178 and then Is_Concurrent_Type (Parent_Type)
13179 and then not Is_Interface (Parent_Type)
13182 ("parent type of a record extension cannot be "
13183 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
13184 Set_Etype (T, Any_Type);
13188 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
13191 if Is_Tagged_Type (Parent_Type)
13192 and then Is_Non_Empty_List (Interface_List (Def))
13199 Intf := First (Interface_List (Def));
13200 while Present (Intf) loop
13201 T := Find_Type_Of_Subtype_Indic (Intf);
13203 if not Is_Interface (T) then
13204 Diagnose_Interface (Intf, T);
13206 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
13207 -- a limited type from having a nonlimited progenitor.
13209 elsif (Limited_Present (Def)
13210 or else (not Is_Interface (Parent_Type)
13211 and then Is_Limited_Type (Parent_Type)))
13212 and then not Is_Limited_Interface (T)
13215 ("progenitor interface& of limited type must be limited",
13224 if Parent_Type = Any_Type
13225 or else Etype (Parent_Type) = Any_Type
13226 or else (Is_Class_Wide_Type (Parent_Type)
13227 and then Etype (Parent_Type) = T)
13229 -- If Parent_Type is undefined or illegal, make new type into a
13230 -- subtype of Any_Type, and set a few attributes to prevent cascaded
13231 -- errors. If this is a self-definition, emit error now.
13234 or else T = Etype (Parent_Type)
13236 Error_Msg_N ("type cannot be used in its own definition", Indic);
13239 Set_Ekind (T, Ekind (Parent_Type));
13240 Set_Etype (T, Any_Type);
13241 Set_Scalar_Range (T, Scalar_Range (Any_Type));
13243 if Is_Tagged_Type (T) then
13244 Set_Primitive_Operations (T, New_Elmt_List);
13250 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
13251 -- an interface is special because the list of interfaces in the full
13252 -- view can be given in any order. For example:
13254 -- type A is interface;
13255 -- type B is interface and A;
13256 -- type D is new B with private;
13258 -- type D is new A and B with null record; -- 1 --
13260 -- In this case we perform the following transformation of -1-:
13262 -- type D is new B and A with null record;
13264 -- If the parent of the full-view covers the parent of the partial-view
13265 -- we have two possible cases:
13267 -- 1) They have the same parent
13268 -- 2) The parent of the full-view implements some further interfaces
13270 -- In both cases we do not need to perform the transformation. In the
13271 -- first case the source program is correct and the transformation is
13272 -- not needed; in the second case the source program does not fulfill
13273 -- the no-hidden interfaces rule (AI-396) and the error will be reported
13276 -- This transformation not only simplifies the rest of the analysis of
13277 -- this type declaration but also simplifies the correct generation of
13278 -- the object layout to the expander.
13280 if In_Private_Part (Current_Scope)
13281 and then Is_Interface (Parent_Type)
13285 Partial_View : Entity_Id;
13286 Partial_View_Parent : Entity_Id;
13287 New_Iface : Node_Id;
13290 -- Look for the associated private type declaration
13292 Partial_View := First_Entity (Current_Scope);
13294 exit when No (Partial_View)
13295 or else (Has_Private_Declaration (Partial_View)
13296 and then Full_View (Partial_View) = T);
13298 Next_Entity (Partial_View);
13301 -- If the partial view was not found then the source code has
13302 -- errors and the transformation is not needed.
13304 if Present (Partial_View) then
13305 Partial_View_Parent := Etype (Partial_View);
13307 -- If the parent of the full-view covers the parent of the
13308 -- partial-view we have nothing else to do.
13310 if Interface_Present_In_Ancestor
13311 (Parent_Type, Partial_View_Parent)
13315 -- Traverse the list of interfaces of the full-view to look
13316 -- for the parent of the partial-view and perform the tree
13320 Iface := First (Interface_List (Def));
13321 while Present (Iface) loop
13322 if Etype (Iface) = Etype (Partial_View) then
13323 Rewrite (Subtype_Indication (Def),
13324 New_Copy (Subtype_Indication
13325 (Parent (Partial_View))));
13327 New_Iface := Make_Identifier (Sloc (N),
13328 Chars (Parent_Type));
13329 Append (New_Iface, Interface_List (Def));
13331 -- Analyze the transformed code
13333 Derived_Type_Declaration (T, N, Is_Completion);
13344 -- Only composite types other than array types are allowed to have
13347 if Present (Discriminant_Specifications (N))
13348 and then (Is_Elementary_Type (Parent_Type)
13349 or else Is_Array_Type (Parent_Type))
13350 and then not Error_Posted (N)
13353 ("elementary or array type cannot have discriminants",
13354 Defining_Identifier (First (Discriminant_Specifications (N))));
13355 Set_Has_Discriminants (T, False);
13358 -- In Ada 83, a derived type defined in a package specification cannot
13359 -- be used for further derivation until the end of its visible part.
13360 -- Note that derivation in the private part of the package is allowed.
13362 if Ada_Version = Ada_83
13363 and then Is_Derived_Type (Parent_Type)
13364 and then In_Visible_Part (Scope (Parent_Type))
13366 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
13368 ("(Ada 83): premature use of type for derivation", Indic);
13372 -- Check for early use of incomplete or private type
13374 if Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
13375 Error_Msg_N ("premature derivation of incomplete type", Indic);
13378 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
13379 and then not Comes_From_Generic (Parent_Type))
13380 or else Has_Private_Component (Parent_Type)
13382 -- The ancestor type of a formal type can be incomplete, in which
13383 -- case only the operations of the partial view are available in
13384 -- the generic. Subsequent checks may be required when the full
13385 -- view is analyzed, to verify that derivation from a tagged type
13386 -- has an extension.
13388 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
13391 elsif No (Underlying_Type (Parent_Type))
13392 or else Has_Private_Component (Parent_Type)
13395 ("premature derivation of derived or private type", Indic);
13397 -- Flag the type itself as being in error, this prevents some
13398 -- nasty problems with subsequent uses of the malformed type.
13400 Set_Error_Posted (T);
13402 -- Check that within the immediate scope of an untagged partial
13403 -- view it's illegal to derive from the partial view if the
13404 -- full view is tagged. (7.3(7))
13406 -- We verify that the Parent_Type is a partial view by checking
13407 -- that it is not a Full_Type_Declaration (i.e. a private type or
13408 -- private extension declaration), to distinguish a partial view
13409 -- from a derivation from a private type which also appears as
13412 elsif Present (Full_View (Parent_Type))
13413 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
13414 and then not Is_Tagged_Type (Parent_Type)
13415 and then Is_Tagged_Type (Full_View (Parent_Type))
13417 Parent_Scope := Scope (T);
13418 while Present (Parent_Scope)
13419 and then Parent_Scope /= Standard_Standard
13421 if Parent_Scope = Scope (Parent_Type) then
13423 ("premature derivation from type with tagged full view",
13427 Parent_Scope := Scope (Parent_Scope);
13432 -- Check that form of derivation is appropriate
13434 Taggd := Is_Tagged_Type (Parent_Type);
13436 -- Perhaps the parent type should be changed to the class-wide type's
13437 -- specific type in this case to prevent cascading errors ???
13439 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
13440 Error_Msg_N ("parent type must not be a class-wide type", Indic);
13444 if Present (Extension) and then not Taggd then
13446 ("type derived from untagged type cannot have extension", Indic);
13448 elsif No (Extension) and then Taggd then
13450 -- If this declaration is within a private part (or body) of a
13451 -- generic instantiation then the derivation is allowed (the parent
13452 -- type can only appear tagged in this case if it's a generic actual
13453 -- type, since it would otherwise have been rejected in the analysis
13454 -- of the generic template).
13456 if not Is_Generic_Actual_Type (Parent_Type)
13457 or else In_Visible_Part (Scope (Parent_Type))
13460 ("type derived from tagged type must have extension", Indic);
13464 -- AI-443: Synchronized formal derived types require a private
13465 -- extension. There is no point in checking the ancestor type or
13466 -- the progenitors since the construct is wrong to begin with.
13468 if Ada_Version >= Ada_05
13469 and then Is_Generic_Type (T)
13470 and then Present (Original_Node (N))
13473 Decl : constant Node_Id := Original_Node (N);
13476 if Nkind (Decl) = N_Formal_Type_Declaration
13477 and then Nkind (Formal_Type_Definition (Decl)) =
13478 N_Formal_Derived_Type_Definition
13479 and then Synchronized_Present (Formal_Type_Definition (Decl))
13480 and then No (Extension)
13482 -- Avoid emitting a duplicate error message
13484 and then not Error_Posted (Indic)
13487 ("synchronized derived type must have extension", N);
13492 if Null_Exclusion_Present (Def)
13493 and then not Is_Access_Type (Parent_Type)
13495 Error_Msg_N ("null exclusion can only apply to an access type", N);
13498 -- Avoid deriving parent primitives of underlying record views
13500 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
13501 Derive_Subps => not Is_Underlying_Record_View (T));
13503 -- AI-419: The parent type of an explicitly limited derived type must
13504 -- be a limited type or a limited interface.
13506 if Limited_Present (Def) then
13507 Set_Is_Limited_Record (T);
13509 if Is_Interface (T) then
13510 Set_Is_Limited_Interface (T);
13513 if not Is_Limited_Type (Parent_Type)
13515 (not Is_Interface (Parent_Type)
13516 or else not Is_Limited_Interface (Parent_Type))
13519 ("parent type& of limited type must be limited",
13523 end Derived_Type_Declaration;
13525 ------------------------
13526 -- Diagnose_Interface --
13527 ------------------------
13529 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
13531 if not Is_Interface (E)
13532 and then E /= Any_Type
13534 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
13536 end Diagnose_Interface;
13538 ----------------------------------
13539 -- Enumeration_Type_Declaration --
13540 ----------------------------------
13542 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
13549 -- Create identifier node representing lower bound
13551 B_Node := New_Node (N_Identifier, Sloc (Def));
13552 L := First (Literals (Def));
13553 Set_Chars (B_Node, Chars (L));
13554 Set_Entity (B_Node, L);
13555 Set_Etype (B_Node, T);
13556 Set_Is_Static_Expression (B_Node, True);
13558 R_Node := New_Node (N_Range, Sloc (Def));
13559 Set_Low_Bound (R_Node, B_Node);
13561 Set_Ekind (T, E_Enumeration_Type);
13562 Set_First_Literal (T, L);
13564 Set_Is_Constrained (T);
13568 -- Loop through literals of enumeration type setting pos and rep values
13569 -- except that if the Ekind is already set, then it means the literal
13570 -- was already constructed (case of a derived type declaration and we
13571 -- should not disturb the Pos and Rep values.
13573 while Present (L) loop
13574 if Ekind (L) /= E_Enumeration_Literal then
13575 Set_Ekind (L, E_Enumeration_Literal);
13576 Set_Enumeration_Pos (L, Ev);
13577 Set_Enumeration_Rep (L, Ev);
13578 Set_Is_Known_Valid (L, True);
13582 New_Overloaded_Entity (L);
13583 Generate_Definition (L);
13584 Set_Convention (L, Convention_Intrinsic);
13586 if Nkind (L) = N_Defining_Character_Literal then
13587 Set_Is_Character_Type (T, True);
13594 -- Now create a node representing upper bound
13596 B_Node := New_Node (N_Identifier, Sloc (Def));
13597 Set_Chars (B_Node, Chars (Last (Literals (Def))));
13598 Set_Entity (B_Node, Last (Literals (Def)));
13599 Set_Etype (B_Node, T);
13600 Set_Is_Static_Expression (B_Node, True);
13602 Set_High_Bound (R_Node, B_Node);
13604 -- Initialize various fields of the type. Some of this information
13605 -- may be overwritten later through rep.clauses.
13607 Set_Scalar_Range (T, R_Node);
13608 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
13609 Set_Enum_Esize (T);
13610 Set_Enum_Pos_To_Rep (T, Empty);
13612 -- Set Discard_Names if configuration pragma set, or if there is
13613 -- a parameterless pragma in the current declarative region
13615 if Global_Discard_Names
13616 or else Discard_Names (Scope (T))
13618 Set_Discard_Names (T);
13621 -- Process end label if there is one
13623 if Present (Def) then
13624 Process_End_Label (Def, 'e', T);
13626 end Enumeration_Type_Declaration;
13628 ---------------------------------
13629 -- Expand_To_Stored_Constraint --
13630 ---------------------------------
13632 function Expand_To_Stored_Constraint
13634 Constraint : Elist_Id) return Elist_Id
13636 Explicitly_Discriminated_Type : Entity_Id;
13637 Expansion : Elist_Id;
13638 Discriminant : Entity_Id;
13640 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
13641 -- Find the nearest type that actually specifies discriminants
13643 ---------------------------------
13644 -- Type_With_Explicit_Discrims --
13645 ---------------------------------
13647 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
13648 Typ : constant E := Base_Type (Id);
13651 if Ekind (Typ) in Incomplete_Or_Private_Kind then
13652 if Present (Full_View (Typ)) then
13653 return Type_With_Explicit_Discrims (Full_View (Typ));
13657 if Has_Discriminants (Typ) then
13662 if Etype (Typ) = Typ then
13664 elsif Has_Discriminants (Typ) then
13667 return Type_With_Explicit_Discrims (Etype (Typ));
13670 end Type_With_Explicit_Discrims;
13672 -- Start of processing for Expand_To_Stored_Constraint
13676 or else Is_Empty_Elmt_List (Constraint)
13681 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
13683 if No (Explicitly_Discriminated_Type) then
13687 Expansion := New_Elmt_List;
13690 First_Stored_Discriminant (Explicitly_Discriminated_Type);
13691 while Present (Discriminant) loop
13693 Get_Discriminant_Value (
13694 Discriminant, Explicitly_Discriminated_Type, Constraint),
13696 Next_Stored_Discriminant (Discriminant);
13700 end Expand_To_Stored_Constraint;
13702 ---------------------------
13703 -- Find_Hidden_Interface --
13704 ---------------------------
13706 function Find_Hidden_Interface
13708 Dest : Elist_Id) return Entity_Id
13711 Iface_Elmt : Elmt_Id;
13714 if Present (Src) and then Present (Dest) then
13715 Iface_Elmt := First_Elmt (Src);
13716 while Present (Iface_Elmt) loop
13717 Iface := Node (Iface_Elmt);
13719 if Is_Interface (Iface)
13720 and then not Contain_Interface (Iface, Dest)
13725 Next_Elmt (Iface_Elmt);
13730 end Find_Hidden_Interface;
13732 --------------------
13733 -- Find_Type_Name --
13734 --------------------
13736 function Find_Type_Name (N : Node_Id) return Entity_Id is
13737 Id : constant Entity_Id := Defining_Identifier (N);
13739 New_Id : Entity_Id;
13740 Prev_Par : Node_Id;
13742 procedure Tag_Mismatch;
13743 -- Diagnose a tagged partial view whose full view is untagged.
13744 -- We post the message on the full view, with a reference to
13745 -- the previous partial view. The partial view can be private
13746 -- or incomplete, and these are handled in a different manner,
13747 -- so we determine the position of the error message from the
13748 -- respective slocs of both.
13754 procedure Tag_Mismatch is
13756 if Sloc (Prev) < Sloc (Id) then
13758 ("full declaration of } must be a tagged type ", Id, Prev);
13761 ("full declaration of } must be a tagged type ", Prev, Id);
13765 -- Start of processing for Find_Type_Name
13768 -- Find incomplete declaration, if one was given
13770 Prev := Current_Entity_In_Scope (Id);
13772 if Present (Prev) then
13774 -- Previous declaration exists. Error if not incomplete/private case
13775 -- except if previous declaration is implicit, etc. Enter_Name will
13776 -- emit error if appropriate.
13778 Prev_Par := Parent (Prev);
13780 if not Is_Incomplete_Or_Private_Type (Prev) then
13784 elsif not Nkind_In (N, N_Full_Type_Declaration,
13785 N_Task_Type_Declaration,
13786 N_Protected_Type_Declaration)
13788 -- Completion must be a full type declarations (RM 7.3(4))
13790 Error_Msg_Sloc := Sloc (Prev);
13791 Error_Msg_NE ("invalid completion of }", Id, Prev);
13793 -- Set scope of Id to avoid cascaded errors. Entity is never
13794 -- examined again, except when saving globals in generics.
13796 Set_Scope (Id, Current_Scope);
13799 -- If this is a repeated incomplete declaration, no further
13800 -- checks are possible.
13802 if Nkind (N) = N_Incomplete_Type_Declaration then
13806 -- Case of full declaration of incomplete type
13808 elsif Ekind (Prev) = E_Incomplete_Type then
13810 -- Indicate that the incomplete declaration has a matching full
13811 -- declaration. The defining occurrence of the incomplete
13812 -- declaration remains the visible one, and the procedure
13813 -- Get_Full_View dereferences it whenever the type is used.
13815 if Present (Full_View (Prev)) then
13816 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
13819 Set_Full_View (Prev, Id);
13820 Append_Entity (Id, Current_Scope);
13821 Set_Is_Public (Id, Is_Public (Prev));
13822 Set_Is_Internal (Id);
13825 -- Case of full declaration of private type
13828 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
13829 if Etype (Prev) /= Prev then
13831 -- Prev is a private subtype or a derived type, and needs
13834 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
13837 elsif Ekind (Prev) = E_Private_Type
13838 and then Nkind_In (N, N_Task_Type_Declaration,
13839 N_Protected_Type_Declaration)
13842 ("completion of nonlimited type cannot be limited", N);
13844 elsif Ekind (Prev) = E_Record_Type_With_Private
13845 and then Nkind_In (N, N_Task_Type_Declaration,
13846 N_Protected_Type_Declaration)
13848 if not Is_Limited_Record (Prev) then
13850 ("completion of nonlimited type cannot be limited", N);
13852 elsif No (Interface_List (N)) then
13854 ("completion of tagged private type must be tagged",
13858 elsif Nkind (N) = N_Full_Type_Declaration
13860 Nkind (Type_Definition (N)) = N_Record_Definition
13861 and then Interface_Present (Type_Definition (N))
13864 ("completion of private type cannot be an interface", N);
13867 -- Ada 2005 (AI-251): Private extension declaration of a task
13868 -- type or a protected type. This case arises when covering
13869 -- interface types.
13871 elsif Nkind_In (N, N_Task_Type_Declaration,
13872 N_Protected_Type_Declaration)
13876 elsif Nkind (N) /= N_Full_Type_Declaration
13877 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
13880 ("full view of private extension must be an extension", N);
13882 elsif not (Abstract_Present (Parent (Prev)))
13883 and then Abstract_Present (Type_Definition (N))
13886 ("full view of non-abstract extension cannot be abstract", N);
13889 if not In_Private_Part (Current_Scope) then
13891 ("declaration of full view must appear in private part", N);
13894 Copy_And_Swap (Prev, Id);
13895 Set_Has_Private_Declaration (Prev);
13896 Set_Has_Private_Declaration (Id);
13898 -- If no error, propagate freeze_node from private to full view.
13899 -- It may have been generated for an early operational item.
13901 if Present (Freeze_Node (Id))
13902 and then Serious_Errors_Detected = 0
13903 and then No (Full_View (Id))
13905 Set_Freeze_Node (Prev, Freeze_Node (Id));
13906 Set_Freeze_Node (Id, Empty);
13907 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
13910 Set_Full_View (Id, Prev);
13914 -- Verify that full declaration conforms to partial one
13916 if Is_Incomplete_Or_Private_Type (Prev)
13917 and then Present (Discriminant_Specifications (Prev_Par))
13919 if Present (Discriminant_Specifications (N)) then
13920 if Ekind (Prev) = E_Incomplete_Type then
13921 Check_Discriminant_Conformance (N, Prev, Prev);
13923 Check_Discriminant_Conformance (N, Prev, Id);
13928 ("missing discriminants in full type declaration", N);
13930 -- To avoid cascaded errors on subsequent use, share the
13931 -- discriminants of the partial view.
13933 Set_Discriminant_Specifications (N,
13934 Discriminant_Specifications (Prev_Par));
13938 -- A prior untagged partial view can have an associated class-wide
13939 -- type due to use of the class attribute, and in this case the full
13940 -- type must also be tagged. This Ada 95 usage is deprecated in favor
13941 -- of incomplete tagged declarations, but we check for it.
13944 and then (Is_Tagged_Type (Prev)
13945 or else Present (Class_Wide_Type (Prev)))
13947 -- The full declaration is either a tagged type (including
13948 -- a synchronized type that implements interfaces) or a
13949 -- type extension, otherwise this is an error.
13951 if Nkind_In (N, N_Task_Type_Declaration,
13952 N_Protected_Type_Declaration)
13954 if No (Interface_List (N))
13955 and then not Error_Posted (N)
13960 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
13962 -- Indicate that the previous declaration (tagged incomplete
13963 -- or private declaration) requires the same on the full one.
13965 if not Tagged_Present (Type_Definition (N)) then
13967 Set_Is_Tagged_Type (Id);
13968 Set_Primitive_Operations (Id, New_Elmt_List);
13971 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
13972 if No (Record_Extension_Part (Type_Definition (N))) then
13974 ("full declaration of } must be a record extension",
13977 -- Set some attributes to produce a usable full view
13979 Set_Is_Tagged_Type (Id);
13980 Set_Primitive_Operations (Id, New_Elmt_List);
13991 -- New type declaration
13996 end Find_Type_Name;
13998 -------------------------
13999 -- Find_Type_Of_Object --
14000 -------------------------
14002 function Find_Type_Of_Object
14003 (Obj_Def : Node_Id;
14004 Related_Nod : Node_Id) return Entity_Id
14006 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
14007 P : Node_Id := Parent (Obj_Def);
14012 -- If the parent is a component_definition node we climb to the
14013 -- component_declaration node
14015 if Nkind (P) = N_Component_Definition then
14019 -- Case of an anonymous array subtype
14021 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
14022 N_Unconstrained_Array_Definition)
14025 Array_Type_Declaration (T, Obj_Def);
14027 -- Create an explicit subtype whenever possible
14029 elsif Nkind (P) /= N_Component_Declaration
14030 and then Def_Kind = N_Subtype_Indication
14032 -- Base name of subtype on object name, which will be unique in
14033 -- the current scope.
14035 -- If this is a duplicate declaration, return base type, to avoid
14036 -- generating duplicate anonymous types.
14038 if Error_Posted (P) then
14039 Analyze (Subtype_Mark (Obj_Def));
14040 return Entity (Subtype_Mark (Obj_Def));
14045 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
14047 T := Make_Defining_Identifier (Sloc (P), Nam);
14049 Insert_Action (Obj_Def,
14050 Make_Subtype_Declaration (Sloc (P),
14051 Defining_Identifier => T,
14052 Subtype_Indication => Relocate_Node (Obj_Def)));
14054 -- This subtype may need freezing, and this will not be done
14055 -- automatically if the object declaration is not in declarative
14056 -- part. Since this is an object declaration, the type cannot always
14057 -- be frozen here. Deferred constants do not freeze their type
14058 -- (which often enough will be private).
14060 if Nkind (P) = N_Object_Declaration
14061 and then Constant_Present (P)
14062 and then No (Expression (P))
14066 Insert_Actions (Obj_Def, Freeze_Entity (T, Sloc (P)));
14069 -- Ada 2005 AI-406: the object definition in an object declaration
14070 -- can be an access definition.
14072 elsif Def_Kind = N_Access_Definition then
14073 T := Access_Definition (Related_Nod, Obj_Def);
14074 Set_Is_Local_Anonymous_Access (T);
14076 -- Otherwise, the object definition is just a subtype_mark
14079 T := Process_Subtype (Obj_Def, Related_Nod);
14083 end Find_Type_Of_Object;
14085 --------------------------------
14086 -- Find_Type_Of_Subtype_Indic --
14087 --------------------------------
14089 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
14093 -- Case of subtype mark with a constraint
14095 if Nkind (S) = N_Subtype_Indication then
14096 Find_Type (Subtype_Mark (S));
14097 Typ := Entity (Subtype_Mark (S));
14100 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
14103 ("incorrect constraint for this kind of type", Constraint (S));
14104 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
14107 -- Otherwise we have a subtype mark without a constraint
14109 elsif Error_Posted (S) then
14110 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
14118 -- Check No_Wide_Characters restriction
14120 if Typ = Standard_Wide_Character
14121 or else Typ = Standard_Wide_Wide_Character
14122 or else Typ = Standard_Wide_String
14123 or else Typ = Standard_Wide_Wide_String
14125 Check_Restriction (No_Wide_Characters, S);
14129 end Find_Type_Of_Subtype_Indic;
14131 -------------------------------------
14132 -- Floating_Point_Type_Declaration --
14133 -------------------------------------
14135 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
14136 Digs : constant Node_Id := Digits_Expression (Def);
14138 Base_Typ : Entity_Id;
14139 Implicit_Base : Entity_Id;
14142 function Can_Derive_From (E : Entity_Id) return Boolean;
14143 -- Find if given digits value allows derivation from specified type
14145 ---------------------
14146 -- Can_Derive_From --
14147 ---------------------
14149 function Can_Derive_From (E : Entity_Id) return Boolean is
14150 Spec : constant Entity_Id := Real_Range_Specification (Def);
14153 if Digs_Val > Digits_Value (E) then
14157 if Present (Spec) then
14158 if Expr_Value_R (Type_Low_Bound (E)) >
14159 Expr_Value_R (Low_Bound (Spec))
14164 if Expr_Value_R (Type_High_Bound (E)) <
14165 Expr_Value_R (High_Bound (Spec))
14172 end Can_Derive_From;
14174 -- Start of processing for Floating_Point_Type_Declaration
14177 Check_Restriction (No_Floating_Point, Def);
14179 -- Create an implicit base type
14182 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
14184 -- Analyze and verify digits value
14186 Analyze_And_Resolve (Digs, Any_Integer);
14187 Check_Digits_Expression (Digs);
14188 Digs_Val := Expr_Value (Digs);
14190 -- Process possible range spec and find correct type to derive from
14192 Process_Real_Range_Specification (Def);
14194 if Can_Derive_From (Standard_Short_Float) then
14195 Base_Typ := Standard_Short_Float;
14196 elsif Can_Derive_From (Standard_Float) then
14197 Base_Typ := Standard_Float;
14198 elsif Can_Derive_From (Standard_Long_Float) then
14199 Base_Typ := Standard_Long_Float;
14200 elsif Can_Derive_From (Standard_Long_Long_Float) then
14201 Base_Typ := Standard_Long_Long_Float;
14203 -- If we can't derive from any existing type, use long_long_float
14204 -- and give appropriate message explaining the problem.
14207 Base_Typ := Standard_Long_Long_Float;
14209 if Digs_Val >= Digits_Value (Standard_Long_Long_Float) then
14210 Error_Msg_Uint_1 := Digits_Value (Standard_Long_Long_Float);
14211 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
14215 ("range too large for any predefined type",
14216 Real_Range_Specification (Def));
14220 -- If there are bounds given in the declaration use them as the bounds
14221 -- of the type, otherwise use the bounds of the predefined base type
14222 -- that was chosen based on the Digits value.
14224 if Present (Real_Range_Specification (Def)) then
14225 Set_Scalar_Range (T, Real_Range_Specification (Def));
14226 Set_Is_Constrained (T);
14228 -- The bounds of this range must be converted to machine numbers
14229 -- in accordance with RM 4.9(38).
14231 Bound := Type_Low_Bound (T);
14233 if Nkind (Bound) = N_Real_Literal then
14235 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
14236 Set_Is_Machine_Number (Bound);
14239 Bound := Type_High_Bound (T);
14241 if Nkind (Bound) = N_Real_Literal then
14243 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
14244 Set_Is_Machine_Number (Bound);
14248 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
14251 -- Complete definition of implicit base and declared first subtype
14253 Set_Etype (Implicit_Base, Base_Typ);
14255 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
14256 Set_Size_Info (Implicit_Base, (Base_Typ));
14257 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
14258 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
14259 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
14260 Set_Vax_Float (Implicit_Base, Vax_Float (Base_Typ));
14262 Set_Ekind (T, E_Floating_Point_Subtype);
14263 Set_Etype (T, Implicit_Base);
14265 Set_Size_Info (T, (Implicit_Base));
14266 Set_RM_Size (T, RM_Size (Implicit_Base));
14267 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
14268 Set_Digits_Value (T, Digs_Val);
14269 end Floating_Point_Type_Declaration;
14271 ----------------------------
14272 -- Get_Discriminant_Value --
14273 ----------------------------
14275 -- This is the situation:
14277 -- There is a non-derived type
14279 -- type T0 (Dx, Dy, Dz...)
14281 -- There are zero or more levels of derivation, with each derivation
14282 -- either purely inheriting the discriminants, or defining its own.
14284 -- type Ti is new Ti-1
14286 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
14288 -- subtype Ti is ...
14290 -- The subtype issue is avoided by the use of Original_Record_Component,
14291 -- and the fact that derived subtypes also derive the constraints.
14293 -- This chain leads back from
14295 -- Typ_For_Constraint
14297 -- Typ_For_Constraint has discriminants, and the value for each
14298 -- discriminant is given by its corresponding Elmt of Constraints.
14300 -- Discriminant is some discriminant in this hierarchy
14302 -- We need to return its value
14304 -- We do this by recursively searching each level, and looking for
14305 -- Discriminant. Once we get to the bottom, we start backing up
14306 -- returning the value for it which may in turn be a discriminant
14307 -- further up, so on the backup we continue the substitution.
14309 function Get_Discriminant_Value
14310 (Discriminant : Entity_Id;
14311 Typ_For_Constraint : Entity_Id;
14312 Constraint : Elist_Id) return Node_Id
14314 function Search_Derivation_Levels
14316 Discrim_Values : Elist_Id;
14317 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
14318 -- This is the routine that performs the recursive search of levels
14319 -- as described above.
14321 ------------------------------
14322 -- Search_Derivation_Levels --
14323 ------------------------------
14325 function Search_Derivation_Levels
14327 Discrim_Values : Elist_Id;
14328 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
14332 Result : Node_Or_Entity_Id;
14333 Result_Entity : Node_Id;
14336 -- If inappropriate type, return Error, this happens only in
14337 -- cascaded error situations, and we want to avoid a blow up.
14339 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
14343 -- Look deeper if possible. Use Stored_Constraints only for
14344 -- untagged types. For tagged types use the given constraint.
14345 -- This asymmetry needs explanation???
14347 if not Stored_Discrim_Values
14348 and then Present (Stored_Constraint (Ti))
14349 and then not Is_Tagged_Type (Ti)
14352 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
14355 Td : constant Entity_Id := Etype (Ti);
14359 Result := Discriminant;
14362 if Present (Stored_Constraint (Ti)) then
14364 Search_Derivation_Levels
14365 (Td, Stored_Constraint (Ti), True);
14368 Search_Derivation_Levels
14369 (Td, Discrim_Values, Stored_Discrim_Values);
14375 -- Extra underlying places to search, if not found above. For
14376 -- concurrent types, the relevant discriminant appears in the
14377 -- corresponding record. For a type derived from a private type
14378 -- without discriminant, the full view inherits the discriminants
14379 -- of the full view of the parent.
14381 if Result = Discriminant then
14382 if Is_Concurrent_Type (Ti)
14383 and then Present (Corresponding_Record_Type (Ti))
14386 Search_Derivation_Levels (
14387 Corresponding_Record_Type (Ti),
14389 Stored_Discrim_Values);
14391 elsif Is_Private_Type (Ti)
14392 and then not Has_Discriminants (Ti)
14393 and then Present (Full_View (Ti))
14394 and then Etype (Full_View (Ti)) /= Ti
14397 Search_Derivation_Levels (
14400 Stored_Discrim_Values);
14404 -- If Result is not a (reference to a) discriminant, return it,
14405 -- otherwise set Result_Entity to the discriminant.
14407 if Nkind (Result) = N_Defining_Identifier then
14408 pragma Assert (Result = Discriminant);
14409 Result_Entity := Result;
14412 if not Denotes_Discriminant (Result) then
14416 Result_Entity := Entity (Result);
14419 -- See if this level of derivation actually has discriminants
14420 -- because tagged derivations can add them, hence the lower
14421 -- levels need not have any.
14423 if not Has_Discriminants (Ti) then
14427 -- Scan Ti's discriminants for Result_Entity,
14428 -- and return its corresponding value, if any.
14430 Result_Entity := Original_Record_Component (Result_Entity);
14432 Assoc := First_Elmt (Discrim_Values);
14434 if Stored_Discrim_Values then
14435 Disc := First_Stored_Discriminant (Ti);
14437 Disc := First_Discriminant (Ti);
14440 while Present (Disc) loop
14441 pragma Assert (Present (Assoc));
14443 if Original_Record_Component (Disc) = Result_Entity then
14444 return Node (Assoc);
14449 if Stored_Discrim_Values then
14450 Next_Stored_Discriminant (Disc);
14452 Next_Discriminant (Disc);
14456 -- Could not find it
14459 end Search_Derivation_Levels;
14463 Result : Node_Or_Entity_Id;
14465 -- Start of processing for Get_Discriminant_Value
14468 -- ??? This routine is a gigantic mess and will be deleted. For the
14469 -- time being just test for the trivial case before calling recurse.
14471 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
14477 D := First_Discriminant (Typ_For_Constraint);
14478 E := First_Elmt (Constraint);
14479 while Present (D) loop
14480 if Chars (D) = Chars (Discriminant) then
14484 Next_Discriminant (D);
14490 Result := Search_Derivation_Levels
14491 (Typ_For_Constraint, Constraint, False);
14493 -- ??? hack to disappear when this routine is gone
14495 if Nkind (Result) = N_Defining_Identifier then
14501 D := First_Discriminant (Typ_For_Constraint);
14502 E := First_Elmt (Constraint);
14503 while Present (D) loop
14504 if Corresponding_Discriminant (D) = Discriminant then
14508 Next_Discriminant (D);
14514 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
14516 end Get_Discriminant_Value;
14518 --------------------------
14519 -- Has_Range_Constraint --
14520 --------------------------
14522 function Has_Range_Constraint (N : Node_Id) return Boolean is
14523 C : constant Node_Id := Constraint (N);
14526 if Nkind (C) = N_Range_Constraint then
14529 elsif Nkind (C) = N_Digits_Constraint then
14531 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
14533 Present (Range_Constraint (C));
14535 elsif Nkind (C) = N_Delta_Constraint then
14536 return Present (Range_Constraint (C));
14541 end Has_Range_Constraint;
14543 ------------------------
14544 -- Inherit_Components --
14545 ------------------------
14547 function Inherit_Components
14549 Parent_Base : Entity_Id;
14550 Derived_Base : Entity_Id;
14551 Is_Tagged : Boolean;
14552 Inherit_Discr : Boolean;
14553 Discs : Elist_Id) return Elist_Id
14555 Assoc_List : constant Elist_Id := New_Elmt_List;
14557 procedure Inherit_Component
14558 (Old_C : Entity_Id;
14559 Plain_Discrim : Boolean := False;
14560 Stored_Discrim : Boolean := False);
14561 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
14562 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
14563 -- True, Old_C is a stored discriminant. If they are both false then
14564 -- Old_C is a regular component.
14566 -----------------------
14567 -- Inherit_Component --
14568 -----------------------
14570 procedure Inherit_Component
14571 (Old_C : Entity_Id;
14572 Plain_Discrim : Boolean := False;
14573 Stored_Discrim : Boolean := False)
14575 New_C : constant Entity_Id := New_Copy (Old_C);
14577 Discrim : Entity_Id;
14578 Corr_Discrim : Entity_Id;
14581 pragma Assert (not Is_Tagged or else not Stored_Discrim);
14583 Set_Parent (New_C, Parent (Old_C));
14585 -- Regular discriminants and components must be inserted in the scope
14586 -- of the Derived_Base. Do it here.
14588 if not Stored_Discrim then
14589 Enter_Name (New_C);
14592 -- For tagged types the Original_Record_Component must point to
14593 -- whatever this field was pointing to in the parent type. This has
14594 -- already been achieved by the call to New_Copy above.
14596 if not Is_Tagged then
14597 Set_Original_Record_Component (New_C, New_C);
14600 -- If we have inherited a component then see if its Etype contains
14601 -- references to Parent_Base discriminants. In this case, replace
14602 -- these references with the constraints given in Discs. We do not
14603 -- do this for the partial view of private types because this is
14604 -- not needed (only the components of the full view will be used
14605 -- for code generation) and cause problem. We also avoid this
14606 -- transformation in some error situations.
14608 if Ekind (New_C) = E_Component then
14609 if (Is_Private_Type (Derived_Base)
14610 and then not Is_Generic_Type (Derived_Base))
14611 or else (Is_Empty_Elmt_List (Discs)
14612 and then not Expander_Active)
14614 Set_Etype (New_C, Etype (Old_C));
14617 -- The current component introduces a circularity of the
14620 -- limited with Pack_2;
14621 -- package Pack_1 is
14622 -- type T_1 is tagged record
14623 -- Comp : access Pack_2.T_2;
14629 -- package Pack_2 is
14630 -- type T_2 is new Pack_1.T_1 with ...;
14635 Constrain_Component_Type
14636 (Old_C, Derived_Base, N, Parent_Base, Discs));
14640 -- In derived tagged types it is illegal to reference a non
14641 -- discriminant component in the parent type. To catch this, mark
14642 -- these components with an Ekind of E_Void. This will be reset in
14643 -- Record_Type_Definition after processing the record extension of
14644 -- the derived type.
14646 -- If the declaration is a private extension, there is no further
14647 -- record extension to process, and the components retain their
14648 -- current kind, because they are visible at this point.
14650 if Is_Tagged and then Ekind (New_C) = E_Component
14651 and then Nkind (N) /= N_Private_Extension_Declaration
14653 Set_Ekind (New_C, E_Void);
14656 if Plain_Discrim then
14657 Set_Corresponding_Discriminant (New_C, Old_C);
14658 Build_Discriminal (New_C);
14660 -- If we are explicitly inheriting a stored discriminant it will be
14661 -- completely hidden.
14663 elsif Stored_Discrim then
14664 Set_Corresponding_Discriminant (New_C, Empty);
14665 Set_Discriminal (New_C, Empty);
14666 Set_Is_Completely_Hidden (New_C);
14668 -- Set the Original_Record_Component of each discriminant in the
14669 -- derived base to point to the corresponding stored that we just
14672 Discrim := First_Discriminant (Derived_Base);
14673 while Present (Discrim) loop
14674 Corr_Discrim := Corresponding_Discriminant (Discrim);
14676 -- Corr_Discrim could be missing in an error situation
14678 if Present (Corr_Discrim)
14679 and then Original_Record_Component (Corr_Discrim) = Old_C
14681 Set_Original_Record_Component (Discrim, New_C);
14684 Next_Discriminant (Discrim);
14687 Append_Entity (New_C, Derived_Base);
14690 if not Is_Tagged then
14691 Append_Elmt (Old_C, Assoc_List);
14692 Append_Elmt (New_C, Assoc_List);
14694 end Inherit_Component;
14696 -- Variables local to Inherit_Component
14698 Loc : constant Source_Ptr := Sloc (N);
14700 Parent_Discrim : Entity_Id;
14701 Stored_Discrim : Entity_Id;
14703 Component : Entity_Id;
14705 -- Start of processing for Inherit_Components
14708 if not Is_Tagged then
14709 Append_Elmt (Parent_Base, Assoc_List);
14710 Append_Elmt (Derived_Base, Assoc_List);
14713 -- Inherit parent discriminants if needed
14715 if Inherit_Discr then
14716 Parent_Discrim := First_Discriminant (Parent_Base);
14717 while Present (Parent_Discrim) loop
14718 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
14719 Next_Discriminant (Parent_Discrim);
14723 -- Create explicit stored discrims for untagged types when necessary
14725 if not Has_Unknown_Discriminants (Derived_Base)
14726 and then Has_Discriminants (Parent_Base)
14727 and then not Is_Tagged
14730 or else First_Discriminant (Parent_Base) /=
14731 First_Stored_Discriminant (Parent_Base))
14733 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
14734 while Present (Stored_Discrim) loop
14735 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
14736 Next_Stored_Discriminant (Stored_Discrim);
14740 -- See if we can apply the second transformation for derived types, as
14741 -- explained in point 6. in the comments above Build_Derived_Record_Type
14742 -- This is achieved by appending Derived_Base discriminants into Discs,
14743 -- which has the side effect of returning a non empty Discs list to the
14744 -- caller of Inherit_Components, which is what we want. This must be
14745 -- done for private derived types if there are explicit stored
14746 -- discriminants, to ensure that we can retrieve the values of the
14747 -- constraints provided in the ancestors.
14750 and then Is_Empty_Elmt_List (Discs)
14751 and then Present (First_Discriminant (Derived_Base))
14753 (not Is_Private_Type (Derived_Base)
14754 or else Is_Completely_Hidden
14755 (First_Stored_Discriminant (Derived_Base))
14756 or else Is_Generic_Type (Derived_Base))
14758 D := First_Discriminant (Derived_Base);
14759 while Present (D) loop
14760 Append_Elmt (New_Reference_To (D, Loc), Discs);
14761 Next_Discriminant (D);
14765 -- Finally, inherit non-discriminant components unless they are not
14766 -- visible because defined or inherited from the full view of the
14767 -- parent. Don't inherit the _parent field of the parent type.
14769 Component := First_Entity (Parent_Base);
14770 while Present (Component) loop
14772 -- Ada 2005 (AI-251): Do not inherit components associated with
14773 -- secondary tags of the parent.
14775 if Ekind (Component) = E_Component
14776 and then Present (Related_Type (Component))
14780 elsif Ekind (Component) /= E_Component
14781 or else Chars (Component) = Name_uParent
14785 -- If the derived type is within the parent type's declarative
14786 -- region, then the components can still be inherited even though
14787 -- they aren't visible at this point. This can occur for cases
14788 -- such as within public child units where the components must
14789 -- become visible upon entering the child unit's private part.
14791 elsif not Is_Visible_Component (Component)
14792 and then not In_Open_Scopes (Scope (Parent_Base))
14796 elsif Ekind_In (Derived_Base, E_Private_Type,
14797 E_Limited_Private_Type)
14802 Inherit_Component (Component);
14805 Next_Entity (Component);
14808 -- For tagged derived types, inherited discriminants cannot be used in
14809 -- component declarations of the record extension part. To achieve this
14810 -- we mark the inherited discriminants as not visible.
14812 if Is_Tagged and then Inherit_Discr then
14813 D := First_Discriminant (Derived_Base);
14814 while Present (D) loop
14815 Set_Is_Immediately_Visible (D, False);
14816 Next_Discriminant (D);
14821 end Inherit_Components;
14823 -----------------------
14824 -- Is_Null_Extension --
14825 -----------------------
14827 function Is_Null_Extension (T : Entity_Id) return Boolean is
14828 Type_Decl : constant Node_Id := Parent (Base_Type (T));
14829 Comp_List : Node_Id;
14833 if Nkind (Type_Decl) /= N_Full_Type_Declaration
14834 or else not Is_Tagged_Type (T)
14835 or else Nkind (Type_Definition (Type_Decl)) /=
14836 N_Derived_Type_Definition
14837 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
14843 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
14845 if Present (Discriminant_Specifications (Type_Decl)) then
14848 elsif Present (Comp_List)
14849 and then Is_Non_Empty_List (Component_Items (Comp_List))
14851 Comp := First (Component_Items (Comp_List));
14853 -- Only user-defined components are relevant. The component list
14854 -- may also contain a parent component and internal components
14855 -- corresponding to secondary tags, but these do not determine
14856 -- whether this is a null extension.
14858 while Present (Comp) loop
14859 if Comes_From_Source (Comp) then
14870 end Is_Null_Extension;
14872 --------------------
14873 -- Is_Progenitor --
14874 --------------------
14876 function Is_Progenitor
14877 (Iface : Entity_Id;
14878 Typ : Entity_Id) return Boolean
14881 return Implements_Interface (Typ, Iface,
14882 Exclude_Parents => True);
14885 ------------------------------
14886 -- Is_Valid_Constraint_Kind --
14887 ------------------------------
14889 function Is_Valid_Constraint_Kind
14890 (T_Kind : Type_Kind;
14891 Constraint_Kind : Node_Kind) return Boolean
14895 when Enumeration_Kind |
14897 return Constraint_Kind = N_Range_Constraint;
14899 when Decimal_Fixed_Point_Kind =>
14900 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
14901 N_Range_Constraint);
14903 when Ordinary_Fixed_Point_Kind =>
14904 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
14905 N_Range_Constraint);
14908 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
14909 N_Range_Constraint);
14916 E_Incomplete_Type |
14919 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
14922 return True; -- Error will be detected later
14924 end Is_Valid_Constraint_Kind;
14926 --------------------------
14927 -- Is_Visible_Component --
14928 --------------------------
14930 function Is_Visible_Component (C : Entity_Id) return Boolean is
14931 Original_Comp : Entity_Id := Empty;
14932 Original_Scope : Entity_Id;
14933 Type_Scope : Entity_Id;
14935 function Is_Local_Type (Typ : Entity_Id) return Boolean;
14936 -- Check whether parent type of inherited component is declared locally,
14937 -- possibly within a nested package or instance. The current scope is
14938 -- the derived record itself.
14940 -------------------
14941 -- Is_Local_Type --
14942 -------------------
14944 function Is_Local_Type (Typ : Entity_Id) return Boolean is
14948 Scop := Scope (Typ);
14949 while Present (Scop)
14950 and then Scop /= Standard_Standard
14952 if Scop = Scope (Current_Scope) then
14956 Scop := Scope (Scop);
14962 -- Start of processing for Is_Visible_Component
14965 if Ekind_In (C, E_Component, E_Discriminant) then
14966 Original_Comp := Original_Record_Component (C);
14969 if No (Original_Comp) then
14971 -- Premature usage, or previous error
14976 Original_Scope := Scope (Original_Comp);
14977 Type_Scope := Scope (Base_Type (Scope (C)));
14980 -- This test only concerns tagged types
14982 if not Is_Tagged_Type (Original_Scope) then
14985 -- If it is _Parent or _Tag, there is no visibility issue
14987 elsif not Comes_From_Source (Original_Comp) then
14990 -- If we are in the body of an instantiation, the component is visible
14991 -- even when the parent type (possibly defined in an enclosing unit or
14992 -- in a parent unit) might not.
14994 elsif In_Instance_Body then
14997 -- Discriminants are always visible
14999 elsif Ekind (Original_Comp) = E_Discriminant
15000 and then not Has_Unknown_Discriminants (Original_Scope)
15004 -- If the component has been declared in an ancestor which is currently
15005 -- a private type, then it is not visible. The same applies if the
15006 -- component's containing type is not in an open scope and the original
15007 -- component's enclosing type is a visible full view of a private type
15008 -- (which can occur in cases where an attempt is being made to reference
15009 -- a component in a sibling package that is inherited from a visible
15010 -- component of a type in an ancestor package; the component in the
15011 -- sibling package should not be visible even though the component it
15012 -- inherited from is visible). This does not apply however in the case
15013 -- where the scope of the type is a private child unit, or when the
15014 -- parent comes from a local package in which the ancestor is currently
15015 -- visible. The latter suppression of visibility is needed for cases
15016 -- that are tested in B730006.
15018 elsif Is_Private_Type (Original_Scope)
15020 (not Is_Private_Descendant (Type_Scope)
15021 and then not In_Open_Scopes (Type_Scope)
15022 and then Has_Private_Declaration (Original_Scope))
15024 -- If the type derives from an entity in a formal package, there
15025 -- are no additional visible components.
15027 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
15028 N_Formal_Package_Declaration
15032 -- if we are not in the private part of the current package, there
15033 -- are no additional visible components.
15035 elsif Ekind (Scope (Current_Scope)) = E_Package
15036 and then not In_Private_Part (Scope (Current_Scope))
15041 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
15042 and then In_Open_Scopes (Scope (Original_Scope))
15043 and then Is_Local_Type (Type_Scope);
15046 -- There is another weird way in which a component may be invisible
15047 -- when the private and the full view are not derived from the same
15048 -- ancestor. Here is an example :
15050 -- type A1 is tagged record F1 : integer; end record;
15051 -- type A2 is new A1 with record F2 : integer; end record;
15052 -- type T is new A1 with private;
15054 -- type T is new A2 with null record;
15056 -- In this case, the full view of T inherits F1 and F2 but the private
15057 -- view inherits only F1
15061 Ancestor : Entity_Id := Scope (C);
15065 if Ancestor = Original_Scope then
15067 elsif Ancestor = Etype (Ancestor) then
15071 Ancestor := Etype (Ancestor);
15075 end Is_Visible_Component;
15077 --------------------------
15078 -- Make_Class_Wide_Type --
15079 --------------------------
15081 procedure Make_Class_Wide_Type (T : Entity_Id) is
15082 CW_Type : Entity_Id;
15084 Next_E : Entity_Id;
15087 -- The class wide type can have been defined by the partial view, in
15088 -- which case everything is already done.
15090 if Present (Class_Wide_Type (T)) then
15095 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
15097 -- Inherit root type characteristics
15099 CW_Name := Chars (CW_Type);
15100 Next_E := Next_Entity (CW_Type);
15101 Copy_Node (T, CW_Type);
15102 Set_Comes_From_Source (CW_Type, False);
15103 Set_Chars (CW_Type, CW_Name);
15104 Set_Parent (CW_Type, Parent (T));
15105 Set_Next_Entity (CW_Type, Next_E);
15107 -- Ensure we have a new freeze node for the class-wide type. The partial
15108 -- view may have freeze action of its own, requiring a proper freeze
15109 -- node, and the same freeze node cannot be shared between the two
15112 Set_Has_Delayed_Freeze (CW_Type);
15113 Set_Freeze_Node (CW_Type, Empty);
15115 -- Customize the class-wide type: It has no prim. op., it cannot be
15116 -- abstract and its Etype points back to the specific root type.
15118 Set_Ekind (CW_Type, E_Class_Wide_Type);
15119 Set_Is_Tagged_Type (CW_Type, True);
15120 Set_Primitive_Operations (CW_Type, New_Elmt_List);
15121 Set_Is_Abstract_Type (CW_Type, False);
15122 Set_Is_Constrained (CW_Type, False);
15123 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
15125 if Ekind (T) = E_Class_Wide_Subtype then
15126 Set_Etype (CW_Type, Etype (Base_Type (T)));
15128 Set_Etype (CW_Type, T);
15131 -- If this is the class_wide type of a constrained subtype, it does
15132 -- not have discriminants.
15134 Set_Has_Discriminants (CW_Type,
15135 Has_Discriminants (T) and then not Is_Constrained (T));
15137 Set_Has_Unknown_Discriminants (CW_Type, True);
15138 Set_Class_Wide_Type (T, CW_Type);
15139 Set_Equivalent_Type (CW_Type, Empty);
15141 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
15143 Set_Class_Wide_Type (CW_Type, CW_Type);
15144 end Make_Class_Wide_Type;
15150 procedure Make_Index
15152 Related_Nod : Node_Id;
15153 Related_Id : Entity_Id := Empty;
15154 Suffix_Index : Nat := 1)
15158 Def_Id : Entity_Id := Empty;
15159 Found : Boolean := False;
15162 -- For a discrete range used in a constrained array definition and
15163 -- defined by a range, an implicit conversion to the predefined type
15164 -- INTEGER is assumed if each bound is either a numeric literal, a named
15165 -- number, or an attribute, and the type of both bounds (prior to the
15166 -- implicit conversion) is the type universal_integer. Otherwise, both
15167 -- bounds must be of the same discrete type, other than universal
15168 -- integer; this type must be determinable independently of the
15169 -- context, but using the fact that the type must be discrete and that
15170 -- both bounds must have the same type.
15172 -- Character literals also have a universal type in the absence of
15173 -- of additional context, and are resolved to Standard_Character.
15175 if Nkind (I) = N_Range then
15177 -- The index is given by a range constraint. The bounds are known
15178 -- to be of a consistent type.
15180 if not Is_Overloaded (I) then
15183 -- For universal bounds, choose the specific predefined type
15185 if T = Universal_Integer then
15186 T := Standard_Integer;
15188 elsif T = Any_Character then
15189 Ambiguous_Character (Low_Bound (I));
15191 T := Standard_Character;
15194 -- The node may be overloaded because some user-defined operators
15195 -- are available, but if a universal interpretation exists it is
15196 -- also the selected one.
15198 elsif Universal_Interpretation (I) = Universal_Integer then
15199 T := Standard_Integer;
15205 Ind : Interp_Index;
15209 Get_First_Interp (I, Ind, It);
15210 while Present (It.Typ) loop
15211 if Is_Discrete_Type (It.Typ) then
15214 and then not Covers (It.Typ, T)
15215 and then not Covers (T, It.Typ)
15217 Error_Msg_N ("ambiguous bounds in discrete range", I);
15225 Get_Next_Interp (Ind, It);
15228 if T = Any_Type then
15229 Error_Msg_N ("discrete type required for range", I);
15230 Set_Etype (I, Any_Type);
15233 elsif T = Universal_Integer then
15234 T := Standard_Integer;
15239 if not Is_Discrete_Type (T) then
15240 Error_Msg_N ("discrete type required for range", I);
15241 Set_Etype (I, Any_Type);
15245 if Nkind (Low_Bound (I)) = N_Attribute_Reference
15246 and then Attribute_Name (Low_Bound (I)) = Name_First
15247 and then Is_Entity_Name (Prefix (Low_Bound (I)))
15248 and then Is_Type (Entity (Prefix (Low_Bound (I))))
15249 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (I))))
15251 -- The type of the index will be the type of the prefix, as long
15252 -- as the upper bound is 'Last of the same type.
15254 Def_Id := Entity (Prefix (Low_Bound (I)));
15256 if Nkind (High_Bound (I)) /= N_Attribute_Reference
15257 or else Attribute_Name (High_Bound (I)) /= Name_Last
15258 or else not Is_Entity_Name (Prefix (High_Bound (I)))
15259 or else Entity (Prefix (High_Bound (I))) /= Def_Id
15266 Process_Range_Expr_In_Decl (R, T);
15268 elsif Nkind (I) = N_Subtype_Indication then
15270 -- The index is given by a subtype with a range constraint
15272 T := Base_Type (Entity (Subtype_Mark (I)));
15274 if not Is_Discrete_Type (T) then
15275 Error_Msg_N ("discrete type required for range", I);
15276 Set_Etype (I, Any_Type);
15280 R := Range_Expression (Constraint (I));
15283 Process_Range_Expr_In_Decl (R, Entity (Subtype_Mark (I)));
15285 elsif Nkind (I) = N_Attribute_Reference then
15287 -- The parser guarantees that the attribute is a RANGE attribute
15289 -- If the node denotes the range of a type mark, that is also the
15290 -- resulting type, and we do no need to create an Itype for it.
15292 if Is_Entity_Name (Prefix (I))
15293 and then Comes_From_Source (I)
15294 and then Is_Type (Entity (Prefix (I)))
15295 and then Is_Discrete_Type (Entity (Prefix (I)))
15297 Def_Id := Entity (Prefix (I));
15300 Analyze_And_Resolve (I);
15304 -- If none of the above, must be a subtype. We convert this to a
15305 -- range attribute reference because in the case of declared first
15306 -- named subtypes, the types in the range reference can be different
15307 -- from the type of the entity. A range attribute normalizes the
15308 -- reference and obtains the correct types for the bounds.
15310 -- This transformation is in the nature of an expansion, is only
15311 -- done if expansion is active. In particular, it is not done on
15312 -- formal generic types, because we need to retain the name of the
15313 -- original index for instantiation purposes.
15316 if not Is_Entity_Name (I) or else not Is_Type (Entity (I)) then
15317 Error_Msg_N ("invalid subtype mark in discrete range ", I);
15318 Set_Etype (I, Any_Integer);
15322 -- The type mark may be that of an incomplete type. It is only
15323 -- now that we can get the full view, previous analysis does
15324 -- not look specifically for a type mark.
15326 Set_Entity (I, Get_Full_View (Entity (I)));
15327 Set_Etype (I, Entity (I));
15328 Def_Id := Entity (I);
15330 if not Is_Discrete_Type (Def_Id) then
15331 Error_Msg_N ("discrete type required for index", I);
15332 Set_Etype (I, Any_Type);
15337 if Expander_Active then
15339 Make_Attribute_Reference (Sloc (I),
15340 Attribute_Name => Name_Range,
15341 Prefix => Relocate_Node (I)));
15343 -- The original was a subtype mark that does not freeze. This
15344 -- means that the rewritten version must not freeze either.
15346 Set_Must_Not_Freeze (I);
15347 Set_Must_Not_Freeze (Prefix (I));
15349 -- Is order critical??? if so, document why, if not
15350 -- use Analyze_And_Resolve
15352 Analyze_And_Resolve (I);
15356 -- If expander is inactive, type is legal, nothing else to construct
15363 if not Is_Discrete_Type (T) then
15364 Error_Msg_N ("discrete type required for range", I);
15365 Set_Etype (I, Any_Type);
15368 elsif T = Any_Type then
15369 Set_Etype (I, Any_Type);
15373 -- We will now create the appropriate Itype to describe the range, but
15374 -- first a check. If we originally had a subtype, then we just label
15375 -- the range with this subtype. Not only is there no need to construct
15376 -- a new subtype, but it is wrong to do so for two reasons:
15378 -- 1. A legality concern, if we have a subtype, it must not freeze,
15379 -- and the Itype would cause freezing incorrectly
15381 -- 2. An efficiency concern, if we created an Itype, it would not be
15382 -- recognized as the same type for the purposes of eliminating
15383 -- checks in some circumstances.
15385 -- We signal this case by setting the subtype entity in Def_Id
15387 if No (Def_Id) then
15389 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
15390 Set_Etype (Def_Id, Base_Type (T));
15392 if Is_Signed_Integer_Type (T) then
15393 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
15395 elsif Is_Modular_Integer_Type (T) then
15396 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
15399 Set_Ekind (Def_Id, E_Enumeration_Subtype);
15400 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
15401 Set_First_Literal (Def_Id, First_Literal (T));
15404 Set_Size_Info (Def_Id, (T));
15405 Set_RM_Size (Def_Id, RM_Size (T));
15406 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
15408 Set_Scalar_Range (Def_Id, R);
15409 Conditional_Delay (Def_Id, T);
15411 -- In the subtype indication case, if the immediate parent of the
15412 -- new subtype is non-static, then the subtype we create is non-
15413 -- static, even if its bounds are static.
15415 if Nkind (I) = N_Subtype_Indication
15416 and then not Is_Static_Subtype (Entity (Subtype_Mark (I)))
15418 Set_Is_Non_Static_Subtype (Def_Id);
15422 -- Final step is to label the index with this constructed type
15424 Set_Etype (I, Def_Id);
15427 ------------------------------
15428 -- Modular_Type_Declaration --
15429 ------------------------------
15431 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
15432 Mod_Expr : constant Node_Id := Expression (Def);
15435 procedure Set_Modular_Size (Bits : Int);
15436 -- Sets RM_Size to Bits, and Esize to normal word size above this
15438 ----------------------
15439 -- Set_Modular_Size --
15440 ----------------------
15442 procedure Set_Modular_Size (Bits : Int) is
15444 Set_RM_Size (T, UI_From_Int (Bits));
15449 elsif Bits <= 16 then
15450 Init_Esize (T, 16);
15452 elsif Bits <= 32 then
15453 Init_Esize (T, 32);
15456 Init_Esize (T, System_Max_Binary_Modulus_Power);
15459 if not Non_Binary_Modulus (T)
15460 and then Esize (T) = RM_Size (T)
15462 Set_Is_Known_Valid (T);
15464 end Set_Modular_Size;
15466 -- Start of processing for Modular_Type_Declaration
15469 Analyze_And_Resolve (Mod_Expr, Any_Integer);
15471 Set_Ekind (T, E_Modular_Integer_Type);
15472 Init_Alignment (T);
15473 Set_Is_Constrained (T);
15475 if not Is_OK_Static_Expression (Mod_Expr) then
15476 Flag_Non_Static_Expr
15477 ("non-static expression used for modular type bound!", Mod_Expr);
15478 M_Val := 2 ** System_Max_Binary_Modulus_Power;
15480 M_Val := Expr_Value (Mod_Expr);
15484 Error_Msg_N ("modulus value must be positive", Mod_Expr);
15485 M_Val := 2 ** System_Max_Binary_Modulus_Power;
15488 Set_Modulus (T, M_Val);
15490 -- Create bounds for the modular type based on the modulus given in
15491 -- the type declaration and then analyze and resolve those bounds.
15493 Set_Scalar_Range (T,
15494 Make_Range (Sloc (Mod_Expr),
15496 Make_Integer_Literal (Sloc (Mod_Expr), 0),
15498 Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
15500 -- Properly analyze the literals for the range. We do this manually
15501 -- because we can't go calling Resolve, since we are resolving these
15502 -- bounds with the type, and this type is certainly not complete yet!
15504 Set_Etype (Low_Bound (Scalar_Range (T)), T);
15505 Set_Etype (High_Bound (Scalar_Range (T)), T);
15506 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
15507 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
15509 -- Loop through powers of two to find number of bits required
15511 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
15515 if M_Val = 2 ** Bits then
15516 Set_Modular_Size (Bits);
15521 elsif M_Val < 2 ** Bits then
15522 Set_Non_Binary_Modulus (T);
15524 if Bits > System_Max_Nonbinary_Modulus_Power then
15525 Error_Msg_Uint_1 :=
15526 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
15528 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
15529 Set_Modular_Size (System_Max_Binary_Modulus_Power);
15533 -- In the non-binary case, set size as per RM 13.3(55)
15535 Set_Modular_Size (Bits);
15542 -- If we fall through, then the size exceed System.Max_Binary_Modulus
15543 -- so we just signal an error and set the maximum size.
15545 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
15546 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
15548 Set_Modular_Size (System_Max_Binary_Modulus_Power);
15549 Init_Alignment (T);
15551 end Modular_Type_Declaration;
15553 --------------------------
15554 -- New_Concatenation_Op --
15555 --------------------------
15557 procedure New_Concatenation_Op (Typ : Entity_Id) is
15558 Loc : constant Source_Ptr := Sloc (Typ);
15561 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
15562 -- Create abbreviated declaration for the formal of a predefined
15563 -- Operator 'Op' of type 'Typ'
15565 --------------------
15566 -- Make_Op_Formal --
15567 --------------------
15569 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
15570 Formal : Entity_Id;
15572 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
15573 Set_Etype (Formal, Typ);
15574 Set_Mechanism (Formal, Default_Mechanism);
15576 end Make_Op_Formal;
15578 -- Start of processing for New_Concatenation_Op
15581 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
15583 Set_Ekind (Op, E_Operator);
15584 Set_Scope (Op, Current_Scope);
15585 Set_Etype (Op, Typ);
15586 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
15587 Set_Is_Immediately_Visible (Op);
15588 Set_Is_Intrinsic_Subprogram (Op);
15589 Set_Has_Completion (Op);
15590 Append_Entity (Op, Current_Scope);
15592 Set_Name_Entity_Id (Name_Op_Concat, Op);
15594 Append_Entity (Make_Op_Formal (Typ, Op), Op);
15595 Append_Entity (Make_Op_Formal (Typ, Op), Op);
15596 end New_Concatenation_Op;
15598 -------------------------
15599 -- OK_For_Limited_Init --
15600 -------------------------
15602 -- ???Check all calls of this, and compare the conditions under which it's
15605 function OK_For_Limited_Init
15607 Exp : Node_Id) return Boolean
15610 return Is_CPP_Constructor_Call (Exp)
15611 or else (Ada_Version >= Ada_05
15612 and then not Debug_Flag_Dot_L
15613 and then OK_For_Limited_Init_In_05 (Typ, Exp));
15614 end OK_For_Limited_Init;
15616 -------------------------------
15617 -- OK_For_Limited_Init_In_05 --
15618 -------------------------------
15620 function OK_For_Limited_Init_In_05
15622 Exp : Node_Id) return Boolean
15625 -- An object of a limited interface type can be initialized with any
15626 -- expression of a nonlimited descendant type.
15628 if Is_Class_Wide_Type (Typ)
15629 and then Is_Limited_Interface (Typ)
15630 and then not Is_Limited_Type (Etype (Exp))
15635 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
15636 -- case of limited aggregates (including extension aggregates), and
15637 -- function calls. The function call may have been give in prefixed
15638 -- notation, in which case the original node is an indexed component.
15640 case Nkind (Original_Node (Exp)) is
15641 when N_Aggregate | N_Extension_Aggregate | N_Function_Call | N_Op =>
15644 when N_Qualified_Expression =>
15646 OK_For_Limited_Init_In_05
15647 (Typ, Expression (Original_Node (Exp)));
15649 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
15650 -- with a function call, the expander has rewritten the call into an
15651 -- N_Type_Conversion node to force displacement of the pointer to
15652 -- reference the component containing the secondary dispatch table.
15653 -- Otherwise a type conversion is not a legal context.
15654 -- A return statement for a build-in-place function returning a
15655 -- synchronized type also introduces an unchecked conversion.
15657 when N_Type_Conversion | N_Unchecked_Type_Conversion =>
15658 return not Comes_From_Source (Exp)
15660 OK_For_Limited_Init_In_05
15661 (Typ, Expression (Original_Node (Exp)));
15663 when N_Indexed_Component | N_Selected_Component =>
15664 return Nkind (Exp) = N_Function_Call;
15666 -- A use of 'Input is a function call, hence allowed. Normally the
15667 -- attribute will be changed to a call, but the attribute by itself
15668 -- can occur with -gnatc.
15670 when N_Attribute_Reference =>
15671 return Attribute_Name (Original_Node (Exp)) = Name_Input;
15676 end OK_For_Limited_Init_In_05;
15678 -------------------------------------------
15679 -- Ordinary_Fixed_Point_Type_Declaration --
15680 -------------------------------------------
15682 procedure Ordinary_Fixed_Point_Type_Declaration
15686 Loc : constant Source_Ptr := Sloc (Def);
15687 Delta_Expr : constant Node_Id := Delta_Expression (Def);
15688 RRS : constant Node_Id := Real_Range_Specification (Def);
15689 Implicit_Base : Entity_Id;
15696 Check_Restriction (No_Fixed_Point, Def);
15698 -- Create implicit base type
15701 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
15702 Set_Etype (Implicit_Base, Implicit_Base);
15704 -- Analyze and process delta expression
15706 Analyze_And_Resolve (Delta_Expr, Any_Real);
15708 Check_Delta_Expression (Delta_Expr);
15709 Delta_Val := Expr_Value_R (Delta_Expr);
15711 Set_Delta_Value (Implicit_Base, Delta_Val);
15713 -- Compute default small from given delta, which is the largest power
15714 -- of two that does not exceed the given delta value.
15724 if Delta_Val < Ureal_1 then
15725 while Delta_Val < Tmp loop
15726 Tmp := Tmp / Ureal_2;
15727 Scale := Scale + 1;
15732 Tmp := Tmp * Ureal_2;
15733 exit when Tmp > Delta_Val;
15734 Scale := Scale - 1;
15738 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
15741 Set_Small_Value (Implicit_Base, Small_Val);
15743 -- If no range was given, set a dummy range
15745 if RRS <= Empty_Or_Error then
15746 Low_Val := -Small_Val;
15747 High_Val := Small_Val;
15749 -- Otherwise analyze and process given range
15753 Low : constant Node_Id := Low_Bound (RRS);
15754 High : constant Node_Id := High_Bound (RRS);
15757 Analyze_And_Resolve (Low, Any_Real);
15758 Analyze_And_Resolve (High, Any_Real);
15759 Check_Real_Bound (Low);
15760 Check_Real_Bound (High);
15762 -- Obtain and set the range
15764 Low_Val := Expr_Value_R (Low);
15765 High_Val := Expr_Value_R (High);
15767 if Low_Val > High_Val then
15768 Error_Msg_NE ("?fixed point type& has null range", Def, T);
15773 -- The range for both the implicit base and the declared first subtype
15774 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
15775 -- set a temporary range in place. Note that the bounds of the base
15776 -- type will be widened to be symmetrical and to fill the available
15777 -- bits when the type is frozen.
15779 -- We could do this with all discrete types, and probably should, but
15780 -- we absolutely have to do it for fixed-point, since the end-points
15781 -- of the range and the size are determined by the small value, which
15782 -- could be reset before the freeze point.
15784 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
15785 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
15787 -- Complete definition of first subtype
15789 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
15790 Set_Etype (T, Implicit_Base);
15791 Init_Size_Align (T);
15792 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
15793 Set_Small_Value (T, Small_Val);
15794 Set_Delta_Value (T, Delta_Val);
15795 Set_Is_Constrained (T);
15797 end Ordinary_Fixed_Point_Type_Declaration;
15799 ----------------------------------------
15800 -- Prepare_Private_Subtype_Completion --
15801 ----------------------------------------
15803 procedure Prepare_Private_Subtype_Completion
15805 Related_Nod : Node_Id)
15807 Id_B : constant Entity_Id := Base_Type (Id);
15808 Full_B : constant Entity_Id := Full_View (Id_B);
15812 if Present (Full_B) then
15814 -- The Base_Type is already completed, we can complete the subtype
15815 -- now. We have to create a new entity with the same name, Thus we
15816 -- can't use Create_Itype.
15818 -- This is messy, should be fixed ???
15820 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
15821 Set_Is_Itype (Full);
15822 Set_Associated_Node_For_Itype (Full, Related_Nod);
15823 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
15826 -- The parent subtype may be private, but the base might not, in some
15827 -- nested instances. In that case, the subtype does not need to be
15828 -- exchanged. It would still be nice to make private subtypes and their
15829 -- bases consistent at all times ???
15831 if Is_Private_Type (Id_B) then
15832 Append_Elmt (Id, Private_Dependents (Id_B));
15835 end Prepare_Private_Subtype_Completion;
15837 ---------------------------
15838 -- Process_Discriminants --
15839 ---------------------------
15841 procedure Process_Discriminants
15843 Prev : Entity_Id := Empty)
15845 Elist : constant Elist_Id := New_Elmt_List;
15848 Discr_Number : Uint;
15849 Discr_Type : Entity_Id;
15850 Default_Present : Boolean := False;
15851 Default_Not_Present : Boolean := False;
15854 -- A composite type other than an array type can have discriminants.
15855 -- On entry, the current scope is the composite type.
15857 -- The discriminants are initially entered into the scope of the type
15858 -- via Enter_Name with the default Ekind of E_Void to prevent premature
15859 -- use, as explained at the end of this procedure.
15861 Discr := First (Discriminant_Specifications (N));
15862 while Present (Discr) loop
15863 Enter_Name (Defining_Identifier (Discr));
15865 -- For navigation purposes we add a reference to the discriminant
15866 -- in the entity for the type. If the current declaration is a
15867 -- completion, place references on the partial view. Otherwise the
15868 -- type is the current scope.
15870 if Present (Prev) then
15872 -- The references go on the partial view, if present. If the
15873 -- partial view has discriminants, the references have been
15874 -- generated already.
15876 if not Has_Discriminants (Prev) then
15877 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
15881 (Current_Scope, Defining_Identifier (Discr), 'd');
15884 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
15885 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
15887 -- Ada 2005 (AI-254)
15889 if Present (Access_To_Subprogram_Definition
15890 (Discriminant_Type (Discr)))
15891 and then Protected_Present (Access_To_Subprogram_Definition
15892 (Discriminant_Type (Discr)))
15895 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
15899 Find_Type (Discriminant_Type (Discr));
15900 Discr_Type := Etype (Discriminant_Type (Discr));
15902 if Error_Posted (Discriminant_Type (Discr)) then
15903 Discr_Type := Any_Type;
15907 if Is_Access_Type (Discr_Type) then
15909 -- Ada 2005 (AI-230): Access discriminant allowed in non-limited
15912 if Ada_Version < Ada_05 then
15913 Check_Access_Discriminant_Requires_Limited
15914 (Discr, Discriminant_Type (Discr));
15917 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
15919 ("(Ada 83) access discriminant not allowed", Discr);
15922 elsif not Is_Discrete_Type (Discr_Type) then
15923 Error_Msg_N ("discriminants must have a discrete or access type",
15924 Discriminant_Type (Discr));
15927 Set_Etype (Defining_Identifier (Discr), Discr_Type);
15929 -- If a discriminant specification includes the assignment compound
15930 -- delimiter followed by an expression, the expression is the default
15931 -- expression of the discriminant; the default expression must be of
15932 -- the type of the discriminant. (RM 3.7.1) Since this expression is
15933 -- a default expression, we do the special preanalysis, since this
15934 -- expression does not freeze (see "Handling of Default and Per-
15935 -- Object Expressions" in spec of package Sem).
15937 if Present (Expression (Discr)) then
15938 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
15940 if Nkind (N) = N_Formal_Type_Declaration then
15942 ("discriminant defaults not allowed for formal type",
15943 Expression (Discr));
15945 -- Tagged types cannot have defaulted discriminants, but a
15946 -- non-tagged private type with defaulted discriminants
15947 -- can have a tagged completion.
15949 elsif Is_Tagged_Type (Current_Scope)
15950 and then Comes_From_Source (N)
15953 ("discriminants of tagged type cannot have defaults",
15954 Expression (Discr));
15957 Default_Present := True;
15958 Append_Elmt (Expression (Discr), Elist);
15960 -- Tag the defining identifiers for the discriminants with
15961 -- their corresponding default expressions from the tree.
15963 Set_Discriminant_Default_Value
15964 (Defining_Identifier (Discr), Expression (Discr));
15968 Default_Not_Present := True;
15971 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
15972 -- Discr_Type but with the null-exclusion attribute
15974 if Ada_Version >= Ada_05 then
15976 -- Ada 2005 (AI-231): Static checks
15978 if Can_Never_Be_Null (Discr_Type) then
15979 Null_Exclusion_Static_Checks (Discr);
15981 elsif Is_Access_Type (Discr_Type)
15982 and then Null_Exclusion_Present (Discr)
15984 -- No need to check itypes because in their case this check
15985 -- was done at their point of creation
15987 and then not Is_Itype (Discr_Type)
15989 if Can_Never_Be_Null (Discr_Type) then
15991 ("`NOT NULL` not allowed (& already excludes null)",
15996 Set_Etype (Defining_Identifier (Discr),
15997 Create_Null_Excluding_Itype
15999 Related_Nod => Discr));
16001 -- Check for improper null exclusion if the type is otherwise
16002 -- legal for a discriminant.
16004 elsif Null_Exclusion_Present (Discr)
16005 and then Is_Discrete_Type (Discr_Type)
16008 ("null exclusion can only apply to an access type", Discr);
16011 -- Ada 2005 (AI-402): access discriminants of nonlimited types
16012 -- can't have defaults. Synchronized types, or types that are
16013 -- explicitly limited are fine, but special tests apply to derived
16014 -- types in generics: in a generic body we have to assume the
16015 -- worst, and therefore defaults are not allowed if the parent is
16016 -- a generic formal private type (see ACATS B370001).
16018 if Is_Access_Type (Discr_Type) then
16019 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
16020 or else not Default_Present
16021 or else Is_Limited_Record (Current_Scope)
16022 or else Is_Concurrent_Type (Current_Scope)
16023 or else Is_Concurrent_Record_Type (Current_Scope)
16024 or else Ekind (Current_Scope) = E_Limited_Private_Type
16026 if not Is_Derived_Type (Current_Scope)
16027 or else not Is_Generic_Type (Etype (Current_Scope))
16028 or else not In_Package_Body (Scope (Etype (Current_Scope)))
16029 or else Limited_Present
16030 (Type_Definition (Parent (Current_Scope)))
16035 Error_Msg_N ("access discriminants of nonlimited types",
16036 Expression (Discr));
16037 Error_Msg_N ("\cannot have defaults", Expression (Discr));
16040 elsif Present (Expression (Discr)) then
16042 ("(Ada 2005) access discriminants of nonlimited types",
16043 Expression (Discr));
16044 Error_Msg_N ("\cannot have defaults", Expression (Discr));
16052 -- An element list consisting of the default expressions of the
16053 -- discriminants is constructed in the above loop and used to set
16054 -- the Discriminant_Constraint attribute for the type. If an object
16055 -- is declared of this (record or task) type without any explicit
16056 -- discriminant constraint given, this element list will form the
16057 -- actual parameters for the corresponding initialization procedure
16060 Set_Discriminant_Constraint (Current_Scope, Elist);
16061 Set_Stored_Constraint (Current_Scope, No_Elist);
16063 -- Default expressions must be provided either for all or for none
16064 -- of the discriminants of a discriminant part. (RM 3.7.1)
16066 if Default_Present and then Default_Not_Present then
16068 ("incomplete specification of defaults for discriminants", N);
16071 -- The use of the name of a discriminant is not allowed in default
16072 -- expressions of a discriminant part if the specification of the
16073 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
16075 -- To detect this, the discriminant names are entered initially with an
16076 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
16077 -- attempt to use a void entity (for example in an expression that is
16078 -- type-checked) produces the error message: premature usage. Now after
16079 -- completing the semantic analysis of the discriminant part, we can set
16080 -- the Ekind of all the discriminants appropriately.
16082 Discr := First (Discriminant_Specifications (N));
16083 Discr_Number := Uint_1;
16084 while Present (Discr) loop
16085 Id := Defining_Identifier (Discr);
16086 Set_Ekind (Id, E_Discriminant);
16087 Init_Component_Location (Id);
16089 Set_Discriminant_Number (Id, Discr_Number);
16091 -- Make sure this is always set, even in illegal programs
16093 Set_Corresponding_Discriminant (Id, Empty);
16095 -- Initialize the Original_Record_Component to the entity itself.
16096 -- Inherit_Components will propagate the right value to
16097 -- discriminants in derived record types.
16099 Set_Original_Record_Component (Id, Id);
16101 -- Create the discriminal for the discriminant
16103 Build_Discriminal (Id);
16106 Discr_Number := Discr_Number + 1;
16109 Set_Has_Discriminants (Current_Scope);
16110 end Process_Discriminants;
16112 -----------------------
16113 -- Process_Full_View --
16114 -----------------------
16116 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
16117 Priv_Parent : Entity_Id;
16118 Full_Parent : Entity_Id;
16119 Full_Indic : Node_Id;
16121 procedure Collect_Implemented_Interfaces
16123 Ifaces : Elist_Id);
16124 -- Ada 2005: Gather all the interfaces that Typ directly or
16125 -- inherently implements. Duplicate entries are not added to
16126 -- the list Ifaces.
16128 ------------------------------------
16129 -- Collect_Implemented_Interfaces --
16130 ------------------------------------
16132 procedure Collect_Implemented_Interfaces
16137 Iface_Elmt : Elmt_Id;
16140 -- Abstract interfaces are only associated with tagged record types
16142 if not Is_Tagged_Type (Typ)
16143 or else not Is_Record_Type (Typ)
16148 -- Recursively climb to the ancestors
16150 if Etype (Typ) /= Typ
16152 -- Protect the frontend against wrong cyclic declarations like:
16154 -- type B is new A with private;
16155 -- type C is new A with private;
16157 -- type B is new C with null record;
16158 -- type C is new B with null record;
16160 and then Etype (Typ) /= Priv_T
16161 and then Etype (Typ) /= Full_T
16163 -- Keep separate the management of private type declarations
16165 if Ekind (Typ) = E_Record_Type_With_Private then
16167 -- Handle the following erronous case:
16168 -- type Private_Type is tagged private;
16170 -- type Private_Type is new Type_Implementing_Iface;
16172 if Present (Full_View (Typ))
16173 and then Etype (Typ) /= Full_View (Typ)
16175 if Is_Interface (Etype (Typ)) then
16176 Append_Unique_Elmt (Etype (Typ), Ifaces);
16179 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
16182 -- Non-private types
16185 if Is_Interface (Etype (Typ)) then
16186 Append_Unique_Elmt (Etype (Typ), Ifaces);
16189 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
16193 -- Handle entities in the list of abstract interfaces
16195 if Present (Interfaces (Typ)) then
16196 Iface_Elmt := First_Elmt (Interfaces (Typ));
16197 while Present (Iface_Elmt) loop
16198 Iface := Node (Iface_Elmt);
16200 pragma Assert (Is_Interface (Iface));
16202 if not Contain_Interface (Iface, Ifaces) then
16203 Append_Elmt (Iface, Ifaces);
16204 Collect_Implemented_Interfaces (Iface, Ifaces);
16207 Next_Elmt (Iface_Elmt);
16210 end Collect_Implemented_Interfaces;
16212 -- Start of processing for Process_Full_View
16215 -- First some sanity checks that must be done after semantic
16216 -- decoration of the full view and thus cannot be placed with other
16217 -- similar checks in Find_Type_Name
16219 if not Is_Limited_Type (Priv_T)
16220 and then (Is_Limited_Type (Full_T)
16221 or else Is_Limited_Composite (Full_T))
16224 ("completion of nonlimited type cannot be limited", Full_T);
16225 Explain_Limited_Type (Full_T, Full_T);
16227 elsif Is_Abstract_Type (Full_T)
16228 and then not Is_Abstract_Type (Priv_T)
16231 ("completion of nonabstract type cannot be abstract", Full_T);
16233 elsif Is_Tagged_Type (Priv_T)
16234 and then Is_Limited_Type (Priv_T)
16235 and then not Is_Limited_Type (Full_T)
16237 -- If pragma CPP_Class was applied to the private declaration
16238 -- propagate the limitedness to the full-view
16240 if Is_CPP_Class (Priv_T) then
16241 Set_Is_Limited_Record (Full_T);
16243 -- GNAT allow its own definition of Limited_Controlled to disobey
16244 -- this rule in order in ease the implementation. The next test is
16245 -- safe because Root_Controlled is defined in a private system child
16247 elsif Etype (Full_T) = Full_View (RTE (RE_Root_Controlled)) then
16248 Set_Is_Limited_Composite (Full_T);
16251 ("completion of limited tagged type must be limited", Full_T);
16254 elsif Is_Generic_Type (Priv_T) then
16255 Error_Msg_N ("generic type cannot have a completion", Full_T);
16258 -- Check that ancestor interfaces of private and full views are
16259 -- consistent. We omit this check for synchronized types because
16260 -- they are performed on the corresponding record type when frozen.
16262 if Ada_Version >= Ada_05
16263 and then Is_Tagged_Type (Priv_T)
16264 and then Is_Tagged_Type (Full_T)
16265 and then not Is_Concurrent_Type (Full_T)
16269 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
16270 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
16273 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
16274 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
16276 -- Ada 2005 (AI-251): The partial view shall be a descendant of
16277 -- an interface type if and only if the full type is descendant
16278 -- of the interface type (AARM 7.3 (7.3/2).
16280 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
16282 if Present (Iface) then
16284 ("interface & not implemented by full type " &
16285 "(RM-2005 7.3 (7.3/2))", Priv_T, Iface);
16288 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
16290 if Present (Iface) then
16292 ("interface & not implemented by partial view " &
16293 "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
16298 if Is_Tagged_Type (Priv_T)
16299 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
16300 and then Is_Derived_Type (Full_T)
16302 Priv_Parent := Etype (Priv_T);
16304 -- The full view of a private extension may have been transformed
16305 -- into an unconstrained derived type declaration and a subtype
16306 -- declaration (see build_derived_record_type for details).
16308 if Nkind (N) = N_Subtype_Declaration then
16309 Full_Indic := Subtype_Indication (N);
16310 Full_Parent := Etype (Base_Type (Full_T));
16312 Full_Indic := Subtype_Indication (Type_Definition (N));
16313 Full_Parent := Etype (Full_T);
16316 -- Check that the parent type of the full type is a descendant of
16317 -- the ancestor subtype given in the private extension. If either
16318 -- entity has an Etype equal to Any_Type then we had some previous
16319 -- error situation [7.3(8)].
16321 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
16324 -- Ada 2005 (AI-251): Interfaces in the full-typ can be given in
16325 -- any order. Therefore we don't have to check that its parent must
16326 -- be a descendant of the parent of the private type declaration.
16328 elsif Is_Interface (Priv_Parent)
16329 and then Is_Interface (Full_Parent)
16333 -- Ada 2005 (AI-251): If the parent of the private type declaration
16334 -- is an interface there is no need to check that it is an ancestor
16335 -- of the associated full type declaration. The required tests for
16336 -- this case are performed by Build_Derived_Record_Type.
16338 elsif not Is_Interface (Base_Type (Priv_Parent))
16339 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
16342 ("parent of full type must descend from parent"
16343 & " of private extension", Full_Indic);
16345 -- Check the rules of 7.3(10): if the private extension inherits
16346 -- known discriminants, then the full type must also inherit those
16347 -- discriminants from the same (ancestor) type, and the parent
16348 -- subtype of the full type must be constrained if and only if
16349 -- the ancestor subtype of the private extension is constrained.
16351 elsif No (Discriminant_Specifications (Parent (Priv_T)))
16352 and then not Has_Unknown_Discriminants (Priv_T)
16353 and then Has_Discriminants (Base_Type (Priv_Parent))
16356 Priv_Indic : constant Node_Id :=
16357 Subtype_Indication (Parent (Priv_T));
16359 Priv_Constr : constant Boolean :=
16360 Is_Constrained (Priv_Parent)
16362 Nkind (Priv_Indic) = N_Subtype_Indication
16363 or else Is_Constrained (Entity (Priv_Indic));
16365 Full_Constr : constant Boolean :=
16366 Is_Constrained (Full_Parent)
16368 Nkind (Full_Indic) = N_Subtype_Indication
16369 or else Is_Constrained (Entity (Full_Indic));
16371 Priv_Discr : Entity_Id;
16372 Full_Discr : Entity_Id;
16375 Priv_Discr := First_Discriminant (Priv_Parent);
16376 Full_Discr := First_Discriminant (Full_Parent);
16377 while Present (Priv_Discr) and then Present (Full_Discr) loop
16378 if Original_Record_Component (Priv_Discr) =
16379 Original_Record_Component (Full_Discr)
16381 Corresponding_Discriminant (Priv_Discr) =
16382 Corresponding_Discriminant (Full_Discr)
16389 Next_Discriminant (Priv_Discr);
16390 Next_Discriminant (Full_Discr);
16393 if Present (Priv_Discr) or else Present (Full_Discr) then
16395 ("full view must inherit discriminants of the parent type"
16396 & " used in the private extension", Full_Indic);
16398 elsif Priv_Constr and then not Full_Constr then
16400 ("parent subtype of full type must be constrained",
16403 elsif Full_Constr and then not Priv_Constr then
16405 ("parent subtype of full type must be unconstrained",
16410 -- Check the rules of 7.3(12): if a partial view has neither known
16411 -- or unknown discriminants, then the full type declaration shall
16412 -- define a definite subtype.
16414 elsif not Has_Unknown_Discriminants (Priv_T)
16415 and then not Has_Discriminants (Priv_T)
16416 and then not Is_Constrained (Full_T)
16419 ("full view must define a constrained type if partial view"
16420 & " has no discriminants", Full_T);
16423 -- ??????? Do we implement the following properly ?????
16424 -- If the ancestor subtype of a private extension has constrained
16425 -- discriminants, then the parent subtype of the full view shall
16426 -- impose a statically matching constraint on those discriminants
16430 -- For untagged types, verify that a type without discriminants
16431 -- is not completed with an unconstrained type.
16433 if not Is_Indefinite_Subtype (Priv_T)
16434 and then Is_Indefinite_Subtype (Full_T)
16436 Error_Msg_N ("full view of type must be definite subtype", Full_T);
16440 -- AI-419: verify that the use of "limited" is consistent
16443 Orig_Decl : constant Node_Id := Original_Node (N);
16446 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
16447 and then not Limited_Present (Parent (Priv_T))
16448 and then not Synchronized_Present (Parent (Priv_T))
16449 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
16451 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
16452 and then Limited_Present (Type_Definition (Orig_Decl))
16455 ("full view of non-limited extension cannot be limited", N);
16459 -- Ada 2005 (AI-443): A synchronized private extension must be
16460 -- completed by a task or protected type.
16462 if Ada_Version >= Ada_05
16463 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
16464 and then Synchronized_Present (Parent (Priv_T))
16465 and then not Is_Concurrent_Type (Full_T)
16467 Error_Msg_N ("full view of synchronized extension must " &
16468 "be synchronized type", N);
16471 -- Ada 2005 AI-363: if the full view has discriminants with
16472 -- defaults, it is illegal to declare constrained access subtypes
16473 -- whose designated type is the current type. This allows objects
16474 -- of the type that are declared in the heap to be unconstrained.
16476 if not Has_Unknown_Discriminants (Priv_T)
16477 and then not Has_Discriminants (Priv_T)
16478 and then Has_Discriminants (Full_T)
16480 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
16482 Set_Has_Constrained_Partial_View (Full_T);
16483 Set_Has_Constrained_Partial_View (Priv_T);
16486 -- Create a full declaration for all its subtypes recorded in
16487 -- Private_Dependents and swap them similarly to the base type. These
16488 -- are subtypes that have been define before the full declaration of
16489 -- the private type. We also swap the entry in Private_Dependents list
16490 -- so we can properly restore the private view on exit from the scope.
16493 Priv_Elmt : Elmt_Id;
16498 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
16499 while Present (Priv_Elmt) loop
16500 Priv := Node (Priv_Elmt);
16502 if Ekind_In (Priv, E_Private_Subtype,
16503 E_Limited_Private_Subtype,
16504 E_Record_Subtype_With_Private)
16506 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
16507 Set_Is_Itype (Full);
16508 Set_Parent (Full, Parent (Priv));
16509 Set_Associated_Node_For_Itype (Full, N);
16511 -- Now we need to complete the private subtype, but since the
16512 -- base type has already been swapped, we must also swap the
16513 -- subtypes (and thus, reverse the arguments in the call to
16514 -- Complete_Private_Subtype).
16516 Copy_And_Swap (Priv, Full);
16517 Complete_Private_Subtype (Full, Priv, Full_T, N);
16518 Replace_Elmt (Priv_Elmt, Full);
16521 Next_Elmt (Priv_Elmt);
16525 -- If the private view was tagged, copy the new primitive operations
16526 -- from the private view to the full view.
16528 if Is_Tagged_Type (Full_T) then
16530 Disp_Typ : Entity_Id;
16531 Full_List : Elist_Id;
16533 Prim_Elmt : Elmt_Id;
16534 Priv_List : Elist_Id;
16538 L : Elist_Id) return Boolean;
16539 -- Determine whether list L contains element E
16547 L : Elist_Id) return Boolean
16549 List_Elmt : Elmt_Id;
16552 List_Elmt := First_Elmt (L);
16553 while Present (List_Elmt) loop
16554 if Node (List_Elmt) = E then
16558 Next_Elmt (List_Elmt);
16564 -- Start of processing
16567 if Is_Tagged_Type (Priv_T) then
16568 Priv_List := Primitive_Operations (Priv_T);
16569 Prim_Elmt := First_Elmt (Priv_List);
16571 -- In the case of a concurrent type completing a private tagged
16572 -- type, primitives may have been declared in between the two
16573 -- views. These subprograms need to be wrapped the same way
16574 -- entries and protected procedures are handled because they
16575 -- cannot be directly shared by the two views.
16577 if Is_Concurrent_Type (Full_T) then
16579 Conc_Typ : constant Entity_Id :=
16580 Corresponding_Record_Type (Full_T);
16581 Curr_Nod : Node_Id := Parent (Conc_Typ);
16582 Wrap_Spec : Node_Id;
16585 while Present (Prim_Elmt) loop
16586 Prim := Node (Prim_Elmt);
16588 if Comes_From_Source (Prim)
16589 and then not Is_Abstract_Subprogram (Prim)
16592 Make_Subprogram_Declaration (Sloc (Prim),
16596 Obj_Typ => Conc_Typ,
16598 Parameter_Specifications (
16601 Insert_After (Curr_Nod, Wrap_Spec);
16602 Curr_Nod := Wrap_Spec;
16604 Analyze (Wrap_Spec);
16607 Next_Elmt (Prim_Elmt);
16613 -- For non-concurrent types, transfer explicit primitives, but
16614 -- omit those inherited from the parent of the private view
16615 -- since they will be re-inherited later on.
16618 Full_List := Primitive_Operations (Full_T);
16620 while Present (Prim_Elmt) loop
16621 Prim := Node (Prim_Elmt);
16623 if Comes_From_Source (Prim)
16624 and then not Contains (Prim, Full_List)
16626 Append_Elmt (Prim, Full_List);
16629 Next_Elmt (Prim_Elmt);
16633 -- Untagged private view
16636 Full_List := Primitive_Operations (Full_T);
16638 -- In this case the partial view is untagged, so here we locate
16639 -- all of the earlier primitives that need to be treated as
16640 -- dispatching (those that appear between the two views). Note
16641 -- that these additional operations must all be new operations
16642 -- (any earlier operations that override inherited operations
16643 -- of the full view will already have been inserted in the
16644 -- primitives list, marked by Check_Operation_From_Private_View
16645 -- as dispatching. Note that implicit "/=" operators are
16646 -- excluded from being added to the primitives list since they
16647 -- shouldn't be treated as dispatching (tagged "/=" is handled
16650 Prim := Next_Entity (Full_T);
16651 while Present (Prim) and then Prim /= Priv_T loop
16652 if Ekind_In (Prim, E_Procedure, E_Function) then
16653 Disp_Typ := Find_Dispatching_Type (Prim);
16655 if Disp_Typ = Full_T
16656 and then (Chars (Prim) /= Name_Op_Ne
16657 or else Comes_From_Source (Prim))
16659 Check_Controlling_Formals (Full_T, Prim);
16661 if not Is_Dispatching_Operation (Prim) then
16662 Append_Elmt (Prim, Full_List);
16663 Set_Is_Dispatching_Operation (Prim, True);
16664 Set_DT_Position (Prim, No_Uint);
16667 elsif Is_Dispatching_Operation (Prim)
16668 and then Disp_Typ /= Full_T
16671 -- Verify that it is not otherwise controlled by a
16672 -- formal or a return value of type T.
16674 Check_Controlling_Formals (Disp_Typ, Prim);
16678 Next_Entity (Prim);
16682 -- For the tagged case, the two views can share the same
16683 -- Primitive Operation list and the same class wide type.
16684 -- Update attributes of the class-wide type which depend on
16685 -- the full declaration.
16687 if Is_Tagged_Type (Priv_T) then
16688 Set_Primitive_Operations (Priv_T, Full_List);
16689 Set_Class_Wide_Type
16690 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
16692 Set_Has_Task (Class_Wide_Type (Priv_T), Has_Task (Full_T));
16697 -- Ada 2005 AI 161: Check preelaboratable initialization consistency
16699 if Known_To_Have_Preelab_Init (Priv_T) then
16701 -- Case where there is a pragma Preelaborable_Initialization. We
16702 -- always allow this in predefined units, which is a bit of a kludge,
16703 -- but it means we don't have to struggle to meet the requirements in
16704 -- the RM for having Preelaborable Initialization. Otherwise we
16705 -- require that the type meets the RM rules. But we can't check that
16706 -- yet, because of the rule about overriding Ininitialize, so we
16707 -- simply set a flag that will be checked at freeze time.
16709 if not In_Predefined_Unit (Full_T) then
16710 Set_Must_Have_Preelab_Init (Full_T);
16714 -- If pragma CPP_Class was applied to the private type declaration,
16715 -- propagate it now to the full type declaration.
16717 if Is_CPP_Class (Priv_T) then
16718 Set_Is_CPP_Class (Full_T);
16719 Set_Convention (Full_T, Convention_CPP);
16722 -- If the private view has user specified stream attributes, then so has
16725 if Has_Specified_Stream_Read (Priv_T) then
16726 Set_Has_Specified_Stream_Read (Full_T);
16728 if Has_Specified_Stream_Write (Priv_T) then
16729 Set_Has_Specified_Stream_Write (Full_T);
16731 if Has_Specified_Stream_Input (Priv_T) then
16732 Set_Has_Specified_Stream_Input (Full_T);
16734 if Has_Specified_Stream_Output (Priv_T) then
16735 Set_Has_Specified_Stream_Output (Full_T);
16737 end Process_Full_View;
16739 -----------------------------------
16740 -- Process_Incomplete_Dependents --
16741 -----------------------------------
16743 procedure Process_Incomplete_Dependents
16745 Full_T : Entity_Id;
16748 Inc_Elmt : Elmt_Id;
16749 Priv_Dep : Entity_Id;
16750 New_Subt : Entity_Id;
16752 Disc_Constraint : Elist_Id;
16755 if No (Private_Dependents (Inc_T)) then
16759 -- Itypes that may be generated by the completion of an incomplete
16760 -- subtype are not used by the back-end and not attached to the tree.
16761 -- They are created only for constraint-checking purposes.
16763 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
16764 while Present (Inc_Elmt) loop
16765 Priv_Dep := Node (Inc_Elmt);
16767 if Ekind (Priv_Dep) = E_Subprogram_Type then
16769 -- An Access_To_Subprogram type may have a return type or a
16770 -- parameter type that is incomplete. Replace with the full view.
16772 if Etype (Priv_Dep) = Inc_T then
16773 Set_Etype (Priv_Dep, Full_T);
16777 Formal : Entity_Id;
16780 Formal := First_Formal (Priv_Dep);
16781 while Present (Formal) loop
16782 if Etype (Formal) = Inc_T then
16783 Set_Etype (Formal, Full_T);
16786 Next_Formal (Formal);
16790 elsif Is_Overloadable (Priv_Dep) then
16792 -- A protected operation is never dispatching: only its
16793 -- wrapper operation (which has convention Ada) is.
16795 if Is_Tagged_Type (Full_T)
16796 and then Convention (Priv_Dep) /= Convention_Protected
16799 -- Subprogram has an access parameter whose designated type
16800 -- was incomplete. Reexamine declaration now, because it may
16801 -- be a primitive operation of the full type.
16803 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
16804 Set_Is_Dispatching_Operation (Priv_Dep);
16805 Check_Controlling_Formals (Full_T, Priv_Dep);
16808 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
16810 -- Can happen during processing of a body before the completion
16811 -- of a TA type. Ignore, because spec is also on dependent list.
16815 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
16816 -- corresponding subtype of the full view.
16818 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype then
16819 Set_Subtype_Indication
16820 (Parent (Priv_Dep), New_Reference_To (Full_T, Sloc (Priv_Dep)));
16821 Set_Etype (Priv_Dep, Full_T);
16822 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
16823 Set_Analyzed (Parent (Priv_Dep), False);
16825 -- Reanalyze the declaration, suppressing the call to
16826 -- Enter_Name to avoid duplicate names.
16828 Analyze_Subtype_Declaration
16829 (N => Parent (Priv_Dep),
16832 -- Dependent is a subtype
16835 -- We build a new subtype indication using the full view of the
16836 -- incomplete parent. The discriminant constraints have been
16837 -- elaborated already at the point of the subtype declaration.
16839 New_Subt := Create_Itype (E_Void, N);
16841 if Has_Discriminants (Full_T) then
16842 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
16844 Disc_Constraint := No_Elist;
16847 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
16848 Set_Full_View (Priv_Dep, New_Subt);
16851 Next_Elmt (Inc_Elmt);
16853 end Process_Incomplete_Dependents;
16855 --------------------------------
16856 -- Process_Range_Expr_In_Decl --
16857 --------------------------------
16859 procedure Process_Range_Expr_In_Decl
16862 Check_List : List_Id := Empty_List;
16863 R_Check_Off : Boolean := False)
16866 R_Checks : Check_Result;
16867 Type_Decl : Node_Id;
16868 Def_Id : Entity_Id;
16871 Analyze_And_Resolve (R, Base_Type (T));
16873 if Nkind (R) = N_Range then
16874 Lo := Low_Bound (R);
16875 Hi := High_Bound (R);
16877 -- We need to ensure validity of the bounds here, because if we
16878 -- go ahead and do the expansion, then the expanded code will get
16879 -- analyzed with range checks suppressed and we miss the check.
16881 Validity_Check_Range (R);
16883 -- If there were errors in the declaration, try and patch up some
16884 -- common mistakes in the bounds. The cases handled are literals
16885 -- which are Integer where the expected type is Real and vice versa.
16886 -- These corrections allow the compilation process to proceed further
16887 -- along since some basic assumptions of the format of the bounds
16890 if Etype (R) = Any_Type then
16892 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
16894 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
16896 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
16898 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
16900 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
16902 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
16904 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
16906 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
16913 -- If the bounds of the range have been mistakenly given as string
16914 -- literals (perhaps in place of character literals), then an error
16915 -- has already been reported, but we rewrite the string literal as a
16916 -- bound of the range's type to avoid blowups in later processing
16917 -- that looks at static values.
16919 if Nkind (Lo) = N_String_Literal then
16921 Make_Attribute_Reference (Sloc (Lo),
16922 Attribute_Name => Name_First,
16923 Prefix => New_Reference_To (T, Sloc (Lo))));
16924 Analyze_And_Resolve (Lo);
16927 if Nkind (Hi) = N_String_Literal then
16929 Make_Attribute_Reference (Sloc (Hi),
16930 Attribute_Name => Name_First,
16931 Prefix => New_Reference_To (T, Sloc (Hi))));
16932 Analyze_And_Resolve (Hi);
16935 -- If bounds aren't scalar at this point then exit, avoiding
16936 -- problems with further processing of the range in this procedure.
16938 if not Is_Scalar_Type (Etype (Lo)) then
16942 -- Resolve (actually Sem_Eval) has checked that the bounds are in
16943 -- then range of the base type. Here we check whether the bounds
16944 -- are in the range of the subtype itself. Note that if the bounds
16945 -- represent the null range the Constraint_Error exception should
16948 -- ??? The following code should be cleaned up as follows
16950 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
16951 -- is done in the call to Range_Check (R, T); below
16953 -- 2. The use of R_Check_Off should be investigated and possibly
16954 -- removed, this would clean up things a bit.
16956 if Is_Null_Range (Lo, Hi) then
16960 -- Capture values of bounds and generate temporaries for them
16961 -- if needed, before applying checks, since checks may cause
16962 -- duplication of the expression without forcing evaluation.
16964 if Expander_Active then
16965 Force_Evaluation (Lo);
16966 Force_Evaluation (Hi);
16969 -- We use a flag here instead of suppressing checks on the
16970 -- type because the type we check against isn't necessarily
16971 -- the place where we put the check.
16973 if not R_Check_Off then
16974 R_Checks := Get_Range_Checks (R, T);
16976 -- Look up tree to find an appropriate insertion point.
16977 -- This seems really junk code, and very brittle, couldn't
16978 -- we just use an insert actions call of some kind ???
16980 Type_Decl := Parent (R);
16981 while Present (Type_Decl) and then not
16982 (Nkind_In (Type_Decl, N_Full_Type_Declaration,
16983 N_Subtype_Declaration,
16985 N_Task_Type_Declaration)
16987 Nkind_In (Type_Decl, N_Single_Task_Declaration,
16988 N_Protected_Type_Declaration,
16989 N_Single_Protected_Declaration))
16991 Type_Decl := Parent (Type_Decl);
16994 -- Why would Type_Decl not be present??? Without this test,
16995 -- short regression tests fail.
16997 if Present (Type_Decl) then
16999 -- Case of loop statement (more comments ???)
17001 if Nkind (Type_Decl) = N_Loop_Statement then
17006 Indic := Parent (R);
17007 while Present (Indic)
17008 and then Nkind (Indic) /= N_Subtype_Indication
17010 Indic := Parent (Indic);
17013 if Present (Indic) then
17014 Def_Id := Etype (Subtype_Mark (Indic));
17016 Insert_Range_Checks
17022 Do_Before => True);
17026 -- All other cases (more comments ???)
17029 Def_Id := Defining_Identifier (Type_Decl);
17031 if (Ekind (Def_Id) = E_Record_Type
17032 and then Depends_On_Discriminant (R))
17034 (Ekind (Def_Id) = E_Protected_Type
17035 and then Has_Discriminants (Def_Id))
17037 Append_Range_Checks
17038 (R_Checks, Check_List, Def_Id, Sloc (Type_Decl), R);
17041 Insert_Range_Checks
17042 (R_Checks, Type_Decl, Def_Id, Sloc (Type_Decl), R);
17050 elsif Expander_Active then
17051 Get_Index_Bounds (R, Lo, Hi);
17052 Force_Evaluation (Lo);
17053 Force_Evaluation (Hi);
17055 end Process_Range_Expr_In_Decl;
17057 --------------------------------------
17058 -- Process_Real_Range_Specification --
17059 --------------------------------------
17061 procedure Process_Real_Range_Specification (Def : Node_Id) is
17062 Spec : constant Node_Id := Real_Range_Specification (Def);
17065 Err : Boolean := False;
17067 procedure Analyze_Bound (N : Node_Id);
17068 -- Analyze and check one bound
17070 -------------------
17071 -- Analyze_Bound --
17072 -------------------
17074 procedure Analyze_Bound (N : Node_Id) is
17076 Analyze_And_Resolve (N, Any_Real);
17078 if not Is_OK_Static_Expression (N) then
17079 Flag_Non_Static_Expr
17080 ("bound in real type definition is not static!", N);
17085 -- Start of processing for Process_Real_Range_Specification
17088 if Present (Spec) then
17089 Lo := Low_Bound (Spec);
17090 Hi := High_Bound (Spec);
17091 Analyze_Bound (Lo);
17092 Analyze_Bound (Hi);
17094 -- If error, clear away junk range specification
17097 Set_Real_Range_Specification (Def, Empty);
17100 end Process_Real_Range_Specification;
17102 ---------------------
17103 -- Process_Subtype --
17104 ---------------------
17106 function Process_Subtype
17108 Related_Nod : Node_Id;
17109 Related_Id : Entity_Id := Empty;
17110 Suffix : Character := ' ') return Entity_Id
17113 Def_Id : Entity_Id;
17114 Error_Node : Node_Id;
17115 Full_View_Id : Entity_Id;
17116 Subtype_Mark_Id : Entity_Id;
17118 May_Have_Null_Exclusion : Boolean;
17120 procedure Check_Incomplete (T : Entity_Id);
17121 -- Called to verify that an incomplete type is not used prematurely
17123 ----------------------
17124 -- Check_Incomplete --
17125 ----------------------
17127 procedure Check_Incomplete (T : Entity_Id) is
17129 -- Ada 2005 (AI-412): Incomplete subtypes are legal
17131 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
17133 not (Ada_Version >= Ada_05
17135 (Nkind (Parent (T)) = N_Subtype_Declaration
17137 (Nkind (Parent (T)) = N_Subtype_Indication
17138 and then Nkind (Parent (Parent (T))) =
17139 N_Subtype_Declaration)))
17141 Error_Msg_N ("invalid use of type before its full declaration", T);
17143 end Check_Incomplete;
17145 -- Start of processing for Process_Subtype
17148 -- Case of no constraints present
17150 if Nkind (S) /= N_Subtype_Indication then
17152 Check_Incomplete (S);
17155 -- Ada 2005 (AI-231): Static check
17157 if Ada_Version >= Ada_05
17158 and then Present (P)
17159 and then Null_Exclusion_Present (P)
17160 and then Nkind (P) /= N_Access_To_Object_Definition
17161 and then not Is_Access_Type (Entity (S))
17163 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
17166 -- The following is ugly, can't we have a range or even a flag???
17168 May_Have_Null_Exclusion :=
17169 Nkind_In (P, N_Access_Definition,
17170 N_Access_Function_Definition,
17171 N_Access_Procedure_Definition,
17172 N_Access_To_Object_Definition,
17174 N_Component_Definition)
17176 Nkind_In (P, N_Derived_Type_Definition,
17177 N_Discriminant_Specification,
17178 N_Formal_Object_Declaration,
17179 N_Object_Declaration,
17180 N_Object_Renaming_Declaration,
17181 N_Parameter_Specification,
17182 N_Subtype_Declaration);
17184 -- Create an Itype that is a duplicate of Entity (S) but with the
17185 -- null-exclusion attribute
17187 if May_Have_Null_Exclusion
17188 and then Is_Access_Type (Entity (S))
17189 and then Null_Exclusion_Present (P)
17191 -- No need to check the case of an access to object definition.
17192 -- It is correct to define double not-null pointers.
17195 -- type Not_Null_Int_Ptr is not null access Integer;
17196 -- type Acc is not null access Not_Null_Int_Ptr;
17198 and then Nkind (P) /= N_Access_To_Object_Definition
17200 if Can_Never_Be_Null (Entity (S)) then
17201 case Nkind (Related_Nod) is
17202 when N_Full_Type_Declaration =>
17203 if Nkind (Type_Definition (Related_Nod))
17204 in N_Array_Type_Definition
17208 (Component_Definition
17209 (Type_Definition (Related_Nod)));
17212 Subtype_Indication (Type_Definition (Related_Nod));
17215 when N_Subtype_Declaration =>
17216 Error_Node := Subtype_Indication (Related_Nod);
17218 when N_Object_Declaration =>
17219 Error_Node := Object_Definition (Related_Nod);
17221 when N_Component_Declaration =>
17223 Subtype_Indication (Component_Definition (Related_Nod));
17225 when N_Allocator =>
17226 Error_Node := Expression (Related_Nod);
17229 pragma Assert (False);
17230 Error_Node := Related_Nod;
17234 ("`NOT NULL` not allowed (& already excludes null)",
17240 Create_Null_Excluding_Itype
17242 Related_Nod => P));
17243 Set_Entity (S, Etype (S));
17248 -- Case of constraint present, so that we have an N_Subtype_Indication
17249 -- node (this node is created only if constraints are present).
17252 Find_Type (Subtype_Mark (S));
17254 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
17256 (Nkind (Parent (S)) = N_Subtype_Declaration
17257 and then Is_Itype (Defining_Identifier (Parent (S))))
17259 Check_Incomplete (Subtype_Mark (S));
17263 Subtype_Mark_Id := Entity (Subtype_Mark (S));
17265 -- Explicit subtype declaration case
17267 if Nkind (P) = N_Subtype_Declaration then
17268 Def_Id := Defining_Identifier (P);
17270 -- Explicit derived type definition case
17272 elsif Nkind (P) = N_Derived_Type_Definition then
17273 Def_Id := Defining_Identifier (Parent (P));
17275 -- Implicit case, the Def_Id must be created as an implicit type.
17276 -- The one exception arises in the case of concurrent types, array
17277 -- and access types, where other subsidiary implicit types may be
17278 -- created and must appear before the main implicit type. In these
17279 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
17280 -- has not yet been called to create Def_Id.
17283 if Is_Array_Type (Subtype_Mark_Id)
17284 or else Is_Concurrent_Type (Subtype_Mark_Id)
17285 or else Is_Access_Type (Subtype_Mark_Id)
17289 -- For the other cases, we create a new unattached Itype,
17290 -- and set the indication to ensure it gets attached later.
17294 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
17298 -- If the kind of constraint is invalid for this kind of type,
17299 -- then give an error, and then pretend no constraint was given.
17301 if not Is_Valid_Constraint_Kind
17302 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
17305 ("incorrect constraint for this kind of type", Constraint (S));
17307 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
17309 -- Set Ekind of orphan itype, to prevent cascaded errors
17311 if Present (Def_Id) then
17312 Set_Ekind (Def_Id, Ekind (Any_Type));
17315 -- Make recursive call, having got rid of the bogus constraint
17317 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
17320 -- Remaining processing depends on type
17322 case Ekind (Subtype_Mark_Id) is
17323 when Access_Kind =>
17324 Constrain_Access (Def_Id, S, Related_Nod);
17327 and then Is_Itype (Designated_Type (Def_Id))
17328 and then Nkind (Related_Nod) = N_Subtype_Declaration
17329 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
17331 Build_Itype_Reference
17332 (Designated_Type (Def_Id), Related_Nod);
17336 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
17338 when Decimal_Fixed_Point_Kind =>
17339 Constrain_Decimal (Def_Id, S);
17341 when Enumeration_Kind =>
17342 Constrain_Enumeration (Def_Id, S);
17344 when Ordinary_Fixed_Point_Kind =>
17345 Constrain_Ordinary_Fixed (Def_Id, S);
17348 Constrain_Float (Def_Id, S);
17350 when Integer_Kind =>
17351 Constrain_Integer (Def_Id, S);
17353 when E_Record_Type |
17356 E_Incomplete_Type =>
17357 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
17359 if Ekind (Def_Id) = E_Incomplete_Type then
17360 Set_Private_Dependents (Def_Id, New_Elmt_List);
17363 when Private_Kind =>
17364 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
17365 Set_Private_Dependents (Def_Id, New_Elmt_List);
17367 -- In case of an invalid constraint prevent further processing
17368 -- since the type constructed is missing expected fields.
17370 if Etype (Def_Id) = Any_Type then
17374 -- If the full view is that of a task with discriminants,
17375 -- we must constrain both the concurrent type and its
17376 -- corresponding record type. Otherwise we will just propagate
17377 -- the constraint to the full view, if available.
17379 if Present (Full_View (Subtype_Mark_Id))
17380 and then Has_Discriminants (Subtype_Mark_Id)
17381 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
17384 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
17386 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
17387 Constrain_Concurrent (Full_View_Id, S,
17388 Related_Nod, Related_Id, Suffix);
17389 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
17390 Set_Full_View (Def_Id, Full_View_Id);
17392 -- Introduce an explicit reference to the private subtype,
17393 -- to prevent scope anomalies in gigi if first use appears
17394 -- in a nested context, e.g. a later function body.
17395 -- Should this be generated in other contexts than a full
17396 -- type declaration?
17398 if Is_Itype (Def_Id)
17400 Nkind (Parent (P)) = N_Full_Type_Declaration
17402 Build_Itype_Reference (Def_Id, Parent (P));
17406 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
17409 when Concurrent_Kind =>
17410 Constrain_Concurrent (Def_Id, S,
17411 Related_Nod, Related_Id, Suffix);
17414 Error_Msg_N ("invalid subtype mark in subtype indication", S);
17417 -- Size and Convention are always inherited from the base type
17419 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
17420 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
17424 end Process_Subtype;
17426 ---------------------------------------
17427 -- Check_Anonymous_Access_Components --
17428 ---------------------------------------
17430 procedure Check_Anonymous_Access_Components
17431 (Typ_Decl : Node_Id;
17434 Comp_List : Node_Id)
17436 Loc : constant Source_Ptr := Sloc (Typ_Decl);
17437 Anon_Access : Entity_Id;
17440 Comp_Def : Node_Id;
17442 Type_Def : Node_Id;
17444 procedure Build_Incomplete_Type_Declaration;
17445 -- If the record type contains components that include an access to the
17446 -- current record, then create an incomplete type declaration for the
17447 -- record, to be used as the designated type of the anonymous access.
17448 -- This is done only once, and only if there is no previous partial
17449 -- view of the type.
17451 function Designates_T (Subt : Node_Id) return Boolean;
17452 -- Check whether a node designates the enclosing record type, or 'Class
17455 function Mentions_T (Acc_Def : Node_Id) return Boolean;
17456 -- Check whether an access definition includes a reference to
17457 -- the enclosing record type. The reference can be a subtype mark
17458 -- in the access definition itself, a 'Class attribute reference, or
17459 -- recursively a reference appearing in a parameter specification
17460 -- or result definition of an access_to_subprogram definition.
17462 --------------------------------------
17463 -- Build_Incomplete_Type_Declaration --
17464 --------------------------------------
17466 procedure Build_Incomplete_Type_Declaration is
17471 -- Is_Tagged indicates whether the type is tagged. It is tagged if
17472 -- it's "is new ... with record" or else "is tagged record ...".
17474 Is_Tagged : constant Boolean :=
17475 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
17478 (Record_Extension_Part (Type_Definition (Typ_Decl))))
17480 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
17481 and then Tagged_Present (Type_Definition (Typ_Decl)));
17484 -- If there is a previous partial view, no need to create a new one
17485 -- If the partial view, given by Prev, is incomplete, If Prev is
17486 -- a private declaration, full declaration is flagged accordingly.
17488 if Prev /= Typ then
17490 Make_Class_Wide_Type (Prev);
17491 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
17492 Set_Etype (Class_Wide_Type (Typ), Typ);
17497 elsif Has_Private_Declaration (Typ) then
17499 -- If we refer to T'Class inside T, and T is the completion of a
17500 -- private type, then we need to make sure the class-wide type
17504 Make_Class_Wide_Type (Typ);
17509 -- If there was a previous anonymous access type, the incomplete
17510 -- type declaration will have been created already.
17512 elsif Present (Current_Entity (Typ))
17513 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
17514 and then Full_View (Current_Entity (Typ)) = Typ
17517 and then Comes_From_Source (Current_Entity (Typ))
17518 and then not Is_Tagged_Type (Current_Entity (Typ))
17520 Make_Class_Wide_Type (Typ);
17522 ("incomplete view of tagged type should be declared tagged?",
17523 Parent (Current_Entity (Typ)));
17528 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
17529 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
17531 -- Type has already been inserted into the current scope. Remove
17532 -- it, and add incomplete declaration for type, so that subsequent
17533 -- anonymous access types can use it. The entity is unchained from
17534 -- the homonym list and from immediate visibility. After analysis,
17535 -- the entity in the incomplete declaration becomes immediately
17536 -- visible in the record declaration that follows.
17538 H := Current_Entity (Typ);
17541 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
17544 and then Homonym (H) /= Typ
17546 H := Homonym (Typ);
17549 Set_Homonym (H, Homonym (Typ));
17552 Insert_Before (Typ_Decl, Decl);
17554 Set_Full_View (Inc_T, Typ);
17558 -- Create a common class-wide type for both views, and set the
17559 -- Etype of the class-wide type to the full view.
17561 Make_Class_Wide_Type (Inc_T);
17562 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
17563 Set_Etype (Class_Wide_Type (Typ), Typ);
17566 end Build_Incomplete_Type_Declaration;
17572 function Designates_T (Subt : Node_Id) return Boolean is
17573 Type_Id : constant Name_Id := Chars (Typ);
17575 function Names_T (Nam : Node_Id) return Boolean;
17576 -- The record type has not been introduced in the current scope
17577 -- yet, so we must examine the name of the type itself, either
17578 -- an identifier T, or an expanded name of the form P.T, where
17579 -- P denotes the current scope.
17585 function Names_T (Nam : Node_Id) return Boolean is
17587 if Nkind (Nam) = N_Identifier then
17588 return Chars (Nam) = Type_Id;
17590 elsif Nkind (Nam) = N_Selected_Component then
17591 if Chars (Selector_Name (Nam)) = Type_Id then
17592 if Nkind (Prefix (Nam)) = N_Identifier then
17593 return Chars (Prefix (Nam)) = Chars (Current_Scope);
17595 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
17596 return Chars (Selector_Name (Prefix (Nam))) =
17597 Chars (Current_Scope);
17611 -- Start of processing for Designates_T
17614 if Nkind (Subt) = N_Identifier then
17615 return Chars (Subt) = Type_Id;
17617 -- Reference can be through an expanded name which has not been
17618 -- analyzed yet, and which designates enclosing scopes.
17620 elsif Nkind (Subt) = N_Selected_Component then
17621 if Names_T (Subt) then
17624 -- Otherwise it must denote an entity that is already visible.
17625 -- The access definition may name a subtype of the enclosing
17626 -- type, if there is a previous incomplete declaration for it.
17629 Find_Selected_Component (Subt);
17631 Is_Entity_Name (Subt)
17632 and then Scope (Entity (Subt)) = Current_Scope
17634 (Chars (Base_Type (Entity (Subt))) = Type_Id
17636 (Is_Class_Wide_Type (Entity (Subt))
17638 Chars (Etype (Base_Type (Entity (Subt)))) =
17642 -- A reference to the current type may appear as the prefix of
17643 -- a 'Class attribute.
17645 elsif Nkind (Subt) = N_Attribute_Reference
17646 and then Attribute_Name (Subt) = Name_Class
17648 return Names_T (Prefix (Subt));
17659 function Mentions_T (Acc_Def : Node_Id) return Boolean is
17660 Param_Spec : Node_Id;
17662 Acc_Subprg : constant Node_Id :=
17663 Access_To_Subprogram_Definition (Acc_Def);
17666 if No (Acc_Subprg) then
17667 return Designates_T (Subtype_Mark (Acc_Def));
17670 -- Component is an access_to_subprogram: examine its formals,
17671 -- and result definition in the case of an access_to_function.
17673 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
17674 while Present (Param_Spec) loop
17675 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
17676 and then Mentions_T (Parameter_Type (Param_Spec))
17680 elsif Designates_T (Parameter_Type (Param_Spec)) then
17687 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
17688 if Nkind (Result_Definition (Acc_Subprg)) =
17689 N_Access_Definition
17691 return Mentions_T (Result_Definition (Acc_Subprg));
17693 return Designates_T (Result_Definition (Acc_Subprg));
17700 -- Start of processing for Check_Anonymous_Access_Components
17703 if No (Comp_List) then
17707 Comp := First (Component_Items (Comp_List));
17708 while Present (Comp) loop
17709 if Nkind (Comp) = N_Component_Declaration
17711 (Access_Definition (Component_Definition (Comp)))
17713 Mentions_T (Access_Definition (Component_Definition (Comp)))
17715 Comp_Def := Component_Definition (Comp);
17717 Access_To_Subprogram_Definition
17718 (Access_Definition (Comp_Def));
17720 Build_Incomplete_Type_Declaration;
17721 Anon_Access := Make_Temporary (Loc, 'S');
17723 -- Create a declaration for the anonymous access type: either
17724 -- an access_to_object or an access_to_subprogram.
17726 if Present (Acc_Def) then
17727 if Nkind (Acc_Def) = N_Access_Function_Definition then
17729 Make_Access_Function_Definition (Loc,
17730 Parameter_Specifications =>
17731 Parameter_Specifications (Acc_Def),
17732 Result_Definition => Result_Definition (Acc_Def));
17735 Make_Access_Procedure_Definition (Loc,
17736 Parameter_Specifications =>
17737 Parameter_Specifications (Acc_Def));
17742 Make_Access_To_Object_Definition (Loc,
17743 Subtype_Indication =>
17746 (Access_Definition (Comp_Def))));
17748 Set_Constant_Present
17749 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
17751 (Type_Def, All_Present (Access_Definition (Comp_Def)));
17754 Set_Null_Exclusion_Present
17756 Null_Exclusion_Present (Access_Definition (Comp_Def)));
17759 Make_Full_Type_Declaration (Loc,
17760 Defining_Identifier => Anon_Access,
17761 Type_Definition => Type_Def);
17763 Insert_Before (Typ_Decl, Decl);
17766 -- If an access to object, Preserve entity of designated type,
17767 -- for ASIS use, before rewriting the component definition.
17769 if No (Acc_Def) then
17774 Desig := Entity (Subtype_Indication (Type_Def));
17776 -- If the access definition is to the current record,
17777 -- the visible entity at this point is an incomplete
17778 -- type. Retrieve the full view to simplify ASIS queries
17780 if Ekind (Desig) = E_Incomplete_Type then
17781 Desig := Full_View (Desig);
17785 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
17790 Make_Component_Definition (Loc,
17791 Subtype_Indication =>
17792 New_Occurrence_Of (Anon_Access, Loc)));
17794 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
17795 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
17797 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
17800 Set_Is_Local_Anonymous_Access (Anon_Access);
17806 if Present (Variant_Part (Comp_List)) then
17810 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
17811 while Present (V) loop
17812 Check_Anonymous_Access_Components
17813 (Typ_Decl, Typ, Prev, Component_List (V));
17814 Next_Non_Pragma (V);
17818 end Check_Anonymous_Access_Components;
17820 --------------------------------
17821 -- Preanalyze_Spec_Expression --
17822 --------------------------------
17824 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
17825 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
17827 In_Spec_Expression := True;
17828 Preanalyze_And_Resolve (N, T);
17829 In_Spec_Expression := Save_In_Spec_Expression;
17830 end Preanalyze_Spec_Expression;
17832 -----------------------------
17833 -- Record_Type_Declaration --
17834 -----------------------------
17836 procedure Record_Type_Declaration
17841 Def : constant Node_Id := Type_Definition (N);
17842 Is_Tagged : Boolean;
17843 Tag_Comp : Entity_Id;
17846 -- These flags must be initialized before calling Process_Discriminants
17847 -- because this routine makes use of them.
17849 Set_Ekind (T, E_Record_Type);
17851 Init_Size_Align (T);
17852 Set_Interfaces (T, No_Elist);
17853 Set_Stored_Constraint (T, No_Elist);
17857 if Ada_Version < Ada_05
17858 or else not Interface_Present (Def)
17860 -- The flag Is_Tagged_Type might have already been set by
17861 -- Find_Type_Name if it detected an error for declaration T. This
17862 -- arises in the case of private tagged types where the full view
17863 -- omits the word tagged.
17866 Tagged_Present (Def)
17867 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
17869 Set_Is_Tagged_Type (T, Is_Tagged);
17870 Set_Is_Limited_Record (T, Limited_Present (Def));
17872 -- Type is abstract if full declaration carries keyword, or if
17873 -- previous partial view did.
17875 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
17876 or else Abstract_Present (Def));
17880 Analyze_Interface_Declaration (T, Def);
17882 if Present (Discriminant_Specifications (N)) then
17884 ("interface types cannot have discriminants",
17885 Defining_Identifier
17886 (First (Discriminant_Specifications (N))));
17890 -- First pass: if there are self-referential access components,
17891 -- create the required anonymous access type declarations, and if
17892 -- need be an incomplete type declaration for T itself.
17894 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
17896 if Ada_Version >= Ada_05
17897 and then Present (Interface_List (Def))
17899 Check_Interfaces (N, Def);
17902 Ifaces_List : Elist_Id;
17905 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
17906 -- already in the parents.
17910 Ifaces_List => Ifaces_List,
17911 Exclude_Parents => True);
17913 Set_Interfaces (T, Ifaces_List);
17917 -- Records constitute a scope for the component declarations within.
17918 -- The scope is created prior to the processing of these declarations.
17919 -- Discriminants are processed first, so that they are visible when
17920 -- processing the other components. The Ekind of the record type itself
17921 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
17923 -- Enter record scope
17927 -- If an incomplete or private type declaration was already given for
17928 -- the type, then this scope already exists, and the discriminants have
17929 -- been declared within. We must verify that the full declaration
17930 -- matches the incomplete one.
17932 Check_Or_Process_Discriminants (N, T, Prev);
17934 Set_Is_Constrained (T, not Has_Discriminants (T));
17935 Set_Has_Delayed_Freeze (T, True);
17937 -- For tagged types add a manually analyzed component corresponding
17938 -- to the component _tag, the corresponding piece of tree will be
17939 -- expanded as part of the freezing actions if it is not a CPP_Class.
17943 -- Do not add the tag unless we are in expansion mode
17945 if Expander_Active then
17946 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
17947 Enter_Name (Tag_Comp);
17949 Set_Ekind (Tag_Comp, E_Component);
17950 Set_Is_Tag (Tag_Comp);
17951 Set_Is_Aliased (Tag_Comp);
17952 Set_Etype (Tag_Comp, RTE (RE_Tag));
17953 Set_DT_Entry_Count (Tag_Comp, No_Uint);
17954 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
17955 Init_Component_Location (Tag_Comp);
17957 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
17958 -- implemented interfaces.
17960 if Has_Interfaces (T) then
17961 Add_Interface_Tag_Components (N, T);
17965 Make_Class_Wide_Type (T);
17966 Set_Primitive_Operations (T, New_Elmt_List);
17969 -- We must suppress range checks when processing the components
17970 -- of a record in the presence of discriminants, since we don't
17971 -- want spurious checks to be generated during their analysis, but
17972 -- must reset the Suppress_Range_Checks flags after having processed
17973 -- the record definition.
17975 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
17976 -- couldn't we just use the normal range check suppression method here.
17977 -- That would seem cleaner ???
17979 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
17980 Set_Kill_Range_Checks (T, True);
17981 Record_Type_Definition (Def, Prev);
17982 Set_Kill_Range_Checks (T, False);
17984 Record_Type_Definition (Def, Prev);
17987 -- Exit from record scope
17991 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
17992 -- the implemented interfaces and associate them an aliased entity.
17995 and then not Is_Empty_List (Interface_List (Def))
17997 Derive_Progenitor_Subprograms (T, T);
17999 end Record_Type_Declaration;
18001 ----------------------------
18002 -- Record_Type_Definition --
18003 ----------------------------
18005 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
18006 Component : Entity_Id;
18007 Ctrl_Components : Boolean := False;
18008 Final_Storage_Only : Boolean;
18012 if Ekind (Prev_T) = E_Incomplete_Type then
18013 T := Full_View (Prev_T);
18018 Final_Storage_Only := not Is_Controlled (T);
18020 -- Ada 2005: check whether an explicit Limited is present in a derived
18021 -- type declaration.
18023 if Nkind (Parent (Def)) = N_Derived_Type_Definition
18024 and then Limited_Present (Parent (Def))
18026 Set_Is_Limited_Record (T);
18029 -- If the component list of a record type is defined by the reserved
18030 -- word null and there is no discriminant part, then the record type has
18031 -- no components and all records of the type are null records (RM 3.7)
18032 -- This procedure is also called to process the extension part of a
18033 -- record extension, in which case the current scope may have inherited
18037 or else No (Component_List (Def))
18038 or else Null_Present (Component_List (Def))
18043 Analyze_Declarations (Component_Items (Component_List (Def)));
18045 if Present (Variant_Part (Component_List (Def))) then
18046 Analyze (Variant_Part (Component_List (Def)));
18050 -- After completing the semantic analysis of the record definition,
18051 -- record components, both new and inherited, are accessible. Set their
18052 -- kind accordingly. Exclude malformed itypes from illegal declarations,
18053 -- whose Ekind may be void.
18055 Component := First_Entity (Current_Scope);
18056 while Present (Component) loop
18057 if Ekind (Component) = E_Void
18058 and then not Is_Itype (Component)
18060 Set_Ekind (Component, E_Component);
18061 Init_Component_Location (Component);
18064 if Has_Task (Etype (Component)) then
18068 if Ekind (Component) /= E_Component then
18071 -- Do not set Has_Controlled_Component on a class-wide equivalent
18072 -- type. See Make_CW_Equivalent_Type.
18074 elsif not Is_Class_Wide_Equivalent_Type (T)
18075 and then (Has_Controlled_Component (Etype (Component))
18076 or else (Chars (Component) /= Name_uParent
18077 and then Is_Controlled (Etype (Component))))
18079 Set_Has_Controlled_Component (T, True);
18080 Final_Storage_Only :=
18082 and then Finalize_Storage_Only (Etype (Component));
18083 Ctrl_Components := True;
18086 Next_Entity (Component);
18089 -- A Type is Finalize_Storage_Only only if all its controlled components
18092 if Ctrl_Components then
18093 Set_Finalize_Storage_Only (T, Final_Storage_Only);
18096 -- Place reference to end record on the proper entity, which may
18097 -- be a partial view.
18099 if Present (Def) then
18100 Process_End_Label (Def, 'e', Prev_T);
18102 end Record_Type_Definition;
18104 ------------------------
18105 -- Replace_Components --
18106 ------------------------
18108 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
18109 function Process (N : Node_Id) return Traverse_Result;
18115 function Process (N : Node_Id) return Traverse_Result is
18119 if Nkind (N) = N_Discriminant_Specification then
18120 Comp := First_Discriminant (Typ);
18121 while Present (Comp) loop
18122 if Chars (Comp) = Chars (Defining_Identifier (N)) then
18123 Set_Defining_Identifier (N, Comp);
18127 Next_Discriminant (Comp);
18130 elsif Nkind (N) = N_Component_Declaration then
18131 Comp := First_Component (Typ);
18132 while Present (Comp) loop
18133 if Chars (Comp) = Chars (Defining_Identifier (N)) then
18134 Set_Defining_Identifier (N, Comp);
18138 Next_Component (Comp);
18145 procedure Replace is new Traverse_Proc (Process);
18147 -- Start of processing for Replace_Components
18151 end Replace_Components;
18153 -------------------------------
18154 -- Set_Completion_Referenced --
18155 -------------------------------
18157 procedure Set_Completion_Referenced (E : Entity_Id) is
18159 -- If in main unit, mark entity that is a completion as referenced,
18160 -- warnings go on the partial view when needed.
18162 if In_Extended_Main_Source_Unit (E) then
18163 Set_Referenced (E);
18165 end Set_Completion_Referenced;
18167 ---------------------
18168 -- Set_Fixed_Range --
18169 ---------------------
18171 -- The range for fixed-point types is complicated by the fact that we
18172 -- do not know the exact end points at the time of the declaration. This
18173 -- is true for three reasons:
18175 -- A size clause may affect the fudging of the end-points
18176 -- A small clause may affect the values of the end-points
18177 -- We try to include the end-points if it does not affect the size
18179 -- This means that the actual end-points must be established at the point
18180 -- when the type is frozen. Meanwhile, we first narrow the range as
18181 -- permitted (so that it will fit if necessary in a small specified size),
18182 -- and then build a range subtree with these narrowed bounds.
18184 -- Set_Fixed_Range constructs the range from real literal values, and sets
18185 -- the range as the Scalar_Range of the given fixed-point type entity.
18187 -- The parent of this range is set to point to the entity so that it is
18188 -- properly hooked into the tree (unlike normal Scalar_Range entries for
18189 -- other scalar types, which are just pointers to the range in the
18190 -- original tree, this would otherwise be an orphan).
18192 -- The tree is left unanalyzed. When the type is frozen, the processing
18193 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
18194 -- analyzed, and uses this as an indication that it should complete
18195 -- work on the range (it will know the final small and size values).
18197 procedure Set_Fixed_Range
18203 S : constant Node_Id :=
18205 Low_Bound => Make_Real_Literal (Loc, Lo),
18206 High_Bound => Make_Real_Literal (Loc, Hi));
18208 Set_Scalar_Range (E, S);
18210 end Set_Fixed_Range;
18212 ----------------------------------
18213 -- Set_Scalar_Range_For_Subtype --
18214 ----------------------------------
18216 procedure Set_Scalar_Range_For_Subtype
18217 (Def_Id : Entity_Id;
18221 Kind : constant Entity_Kind := Ekind (Def_Id);
18224 Set_Scalar_Range (Def_Id, R);
18226 -- We need to link the range into the tree before resolving it so
18227 -- that types that are referenced, including importantly the subtype
18228 -- itself, are properly frozen (Freeze_Expression requires that the
18229 -- expression be properly linked into the tree). Of course if it is
18230 -- already linked in, then we do not disturb the current link.
18232 if No (Parent (R)) then
18233 Set_Parent (R, Def_Id);
18236 -- Reset the kind of the subtype during analysis of the range, to
18237 -- catch possible premature use in the bounds themselves.
18239 Set_Ekind (Def_Id, E_Void);
18240 Process_Range_Expr_In_Decl (R, Subt);
18241 Set_Ekind (Def_Id, Kind);
18242 end Set_Scalar_Range_For_Subtype;
18244 --------------------------------------------------------
18245 -- Set_Stored_Constraint_From_Discriminant_Constraint --
18246 --------------------------------------------------------
18248 procedure Set_Stored_Constraint_From_Discriminant_Constraint
18252 -- Make sure set if encountered during Expand_To_Stored_Constraint
18254 Set_Stored_Constraint (E, No_Elist);
18256 -- Give it the right value
18258 if Is_Constrained (E) and then Has_Discriminants (E) then
18259 Set_Stored_Constraint (E,
18260 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
18262 end Set_Stored_Constraint_From_Discriminant_Constraint;
18264 -------------------------------------
18265 -- Signed_Integer_Type_Declaration --
18266 -------------------------------------
18268 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
18269 Implicit_Base : Entity_Id;
18270 Base_Typ : Entity_Id;
18273 Errs : Boolean := False;
18277 function Can_Derive_From (E : Entity_Id) return Boolean;
18278 -- Determine whether given bounds allow derivation from specified type
18280 procedure Check_Bound (Expr : Node_Id);
18281 -- Check bound to make sure it is integral and static. If not, post
18282 -- appropriate error message and set Errs flag
18284 ---------------------
18285 -- Can_Derive_From --
18286 ---------------------
18288 -- Note we check both bounds against both end values, to deal with
18289 -- strange types like ones with a range of 0 .. -12341234.
18291 function Can_Derive_From (E : Entity_Id) return Boolean is
18292 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
18293 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
18295 return Lo <= Lo_Val and then Lo_Val <= Hi
18297 Lo <= Hi_Val and then Hi_Val <= Hi;
18298 end Can_Derive_From;
18304 procedure Check_Bound (Expr : Node_Id) is
18306 -- If a range constraint is used as an integer type definition, each
18307 -- bound of the range must be defined by a static expression of some
18308 -- integer type, but the two bounds need not have the same integer
18309 -- type (Negative bounds are allowed.) (RM 3.5.4)
18311 if not Is_Integer_Type (Etype (Expr)) then
18313 ("integer type definition bounds must be of integer type", Expr);
18316 elsif not Is_OK_Static_Expression (Expr) then
18317 Flag_Non_Static_Expr
18318 ("non-static expression used for integer type bound!", Expr);
18321 -- The bounds are folded into literals, and we set their type to be
18322 -- universal, to avoid typing difficulties: we cannot set the type
18323 -- of the literal to the new type, because this would be a forward
18324 -- reference for the back end, and if the original type is user-
18325 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
18328 if Is_Entity_Name (Expr) then
18329 Fold_Uint (Expr, Expr_Value (Expr), True);
18332 Set_Etype (Expr, Universal_Integer);
18336 -- Start of processing for Signed_Integer_Type_Declaration
18339 -- Create an anonymous base type
18342 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
18344 -- Analyze and check the bounds, they can be of any integer type
18346 Lo := Low_Bound (Def);
18347 Hi := High_Bound (Def);
18349 -- Arbitrarily use Integer as the type if either bound had an error
18351 if Hi = Error or else Lo = Error then
18352 Base_Typ := Any_Integer;
18353 Set_Error_Posted (T, True);
18355 -- Here both bounds are OK expressions
18358 Analyze_And_Resolve (Lo, Any_Integer);
18359 Analyze_And_Resolve (Hi, Any_Integer);
18365 Hi := Type_High_Bound (Standard_Long_Long_Integer);
18366 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
18369 -- Find type to derive from
18371 Lo_Val := Expr_Value (Lo);
18372 Hi_Val := Expr_Value (Hi);
18374 if Can_Derive_From (Standard_Short_Short_Integer) then
18375 Base_Typ := Base_Type (Standard_Short_Short_Integer);
18377 elsif Can_Derive_From (Standard_Short_Integer) then
18378 Base_Typ := Base_Type (Standard_Short_Integer);
18380 elsif Can_Derive_From (Standard_Integer) then
18381 Base_Typ := Base_Type (Standard_Integer);
18383 elsif Can_Derive_From (Standard_Long_Integer) then
18384 Base_Typ := Base_Type (Standard_Long_Integer);
18386 elsif Can_Derive_From (Standard_Long_Long_Integer) then
18387 Base_Typ := Base_Type (Standard_Long_Long_Integer);
18390 Base_Typ := Base_Type (Standard_Long_Long_Integer);
18391 Error_Msg_N ("integer type definition bounds out of range", Def);
18392 Hi := Type_High_Bound (Standard_Long_Long_Integer);
18393 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
18397 -- Complete both implicit base and declared first subtype entities
18399 Set_Etype (Implicit_Base, Base_Typ);
18400 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
18401 Set_Size_Info (Implicit_Base, (Base_Typ));
18402 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
18403 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
18405 Set_Ekind (T, E_Signed_Integer_Subtype);
18406 Set_Etype (T, Implicit_Base);
18408 Set_Size_Info (T, (Implicit_Base));
18409 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
18410 Set_Scalar_Range (T, Def);
18411 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
18412 Set_Is_Constrained (T);
18413 end Signed_Integer_Type_Declaration;