1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2019, 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 -- This package contains the routines to process package specifications and
27 -- bodies. The most important semantic aspects of package processing are the
28 -- handling of private and full declarations, and the construction of dispatch
29 -- tables for tagged types.
31 with Aspects; use Aspects;
32 with Atree; use Atree;
33 with Contracts; use Contracts;
34 with Debug; use Debug;
35 with Einfo; use Einfo;
36 with Elists; use Elists;
37 with Errout; use Errout;
38 with Exp_Disp; use Exp_Disp;
39 with Exp_Dist; use Exp_Dist;
40 with Exp_Dbug; use Exp_Dbug;
41 with Freeze; use Freeze;
42 with Ghost; use Ghost;
44 with Lib.Xref; use Lib.Xref;
45 with Namet; use Namet;
46 with Nmake; use Nmake;
47 with Nlists; use Nlists;
49 with Output; use Output;
50 with Restrict; use Restrict;
51 with Rtsfind; use Rtsfind;
53 with Sem_Aux; use Sem_Aux;
54 with Sem_Cat; use Sem_Cat;
55 with Sem_Ch3; use Sem_Ch3;
56 with Sem_Ch6; use Sem_Ch6;
57 with Sem_Ch8; use Sem_Ch8;
58 with Sem_Ch10; use Sem_Ch10;
59 with Sem_Ch12; use Sem_Ch12;
60 with Sem_Ch13; use Sem_Ch13;
61 with Sem_Disp; use Sem_Disp;
62 with Sem_Eval; use Sem_Eval;
63 with Sem_Prag; use Sem_Prag;
64 with Sem_Util; use Sem_Util;
65 with Sem_Warn; use Sem_Warn;
66 with Snames; use Snames;
67 with Stand; use Stand;
68 with Sinfo; use Sinfo;
69 with Sinput; use Sinput;
71 with Uintp; use Uintp;
75 package body Sem_Ch7 is
77 -----------------------------------
78 -- Handling private declarations --
79 -----------------------------------
81 -- The principle that each entity has a single defining occurrence clashes
82 -- with the presence of two separate definitions for private types: the
83 -- first is the private type declaration, and the second is the full type
84 -- declaration. It is important that all references to the type point to
85 -- the same defining occurrence, namely the first one. To enforce the two
86 -- separate views of the entity, the corresponding information is swapped
87 -- between the two declarations. Outside of the package, the defining
88 -- occurrence only contains the private declaration information, while in
89 -- the private part and the body of the package the defining occurrence
90 -- contains the full declaration. To simplify the swap, the defining
91 -- occurrence that currently holds the private declaration points to the
92 -- full declaration. During semantic processing the defining occurrence
93 -- also points to a list of private dependents, that is to say access types
94 -- or composite types whose designated types or component types are
95 -- subtypes or derived types of the private type in question. After the
96 -- full declaration has been seen, the private dependents are updated to
97 -- indicate that they have full definitions.
99 -----------------------
100 -- Local Subprograms --
101 -----------------------
103 procedure Analyze_Package_Body_Helper (N : Node_Id);
104 -- Does all the real work of Analyze_Package_Body
106 procedure Check_Anonymous_Access_Types
107 (Spec_Id : Entity_Id;
109 -- If the spec of a package has a limited_with_clause, it may declare
110 -- anonymous access types whose designated type is a limited view, such an
111 -- anonymous access return type for a function. This access type cannot be
112 -- elaborated in the spec itself, but it may need an itype reference if it
113 -- is used within a nested scope. In that case the itype reference is
114 -- created at the beginning of the corresponding package body and inserted
115 -- before other body declarations.
117 procedure Declare_Inherited_Private_Subprograms (Id : Entity_Id);
118 -- Called upon entering the private part of a public child package and the
119 -- body of a nested package, to potentially declare certain inherited
120 -- subprograms that were inherited by types in the visible part, but whose
121 -- declaration was deferred because the parent operation was private and
122 -- not visible at that point. These subprograms are located by traversing
123 -- the visible part declarations looking for non-private type extensions
124 -- and then examining each of the primitive operations of such types to
125 -- find those that were inherited but declared with a special internal
126 -- name. Each such operation is now declared as an operation with a normal
127 -- name (using the name of the parent operation) and replaces the previous
128 -- implicit operation in the primitive operations list of the type. If the
129 -- inherited private operation has been overridden, then it's replaced by
130 -- the overriding operation.
132 procedure Install_Package_Entity (Id : Entity_Id);
133 -- Supporting procedure for Install_{Visible,Private}_Declarations. Places
134 -- one entity on its visibility chain, and recurses on the visible part if
135 -- the entity is an inner package.
137 function Is_Private_Base_Type (E : Entity_Id) return Boolean;
138 -- True for a private type that is not a subtype
140 function Is_Visible_Dependent (Dep : Entity_Id) return Boolean;
141 -- If the private dependent is a private type whose full view is derived
142 -- from the parent type, its full properties are revealed only if we are in
143 -- the immediate scope of the private dependent. Should this predicate be
144 -- tightened further???
146 function Requires_Completion_In_Body
149 Do_Abstract_States : Boolean := False) return Boolean;
150 -- Subsidiary to routines Unit_Requires_Body and Unit_Requires_Body_Info.
151 -- Determine whether entity Id declared in package spec Pack_Id requires
152 -- completion in a package body. Flag Do_Abstract_Stats should be set when
153 -- abstract states are to be considered in the completion test.
155 procedure Unit_Requires_Body_Info (Pack_Id : Entity_Id);
156 -- Outputs info messages showing why package Pack_Id requires a body. The
157 -- caller has checked that the switch requesting this information is set,
158 -- and that the package does indeed require a body.
160 --------------------------
161 -- Analyze_Package_Body --
162 --------------------------
164 procedure Analyze_Package_Body (N : Node_Id) is
165 Loc : constant Source_Ptr := Sloc (N);
169 Write_Str ("==> package body ");
170 Write_Name (Chars (Defining_Entity (N)));
171 Write_Str (" from ");
172 Write_Location (Loc);
177 -- The real work is split out into the helper, so it can do "return;"
178 -- without skipping the debug output.
180 Analyze_Package_Body_Helper (N);
184 Write_Str ("<== package body ");
185 Write_Name (Chars (Defining_Entity (N)));
186 Write_Str (" from ");
187 Write_Location (Loc);
190 end Analyze_Package_Body;
192 ------------------------------------------------------
193 -- Analyze_Package_Body_Helper Data and Subprograms --
194 ------------------------------------------------------
196 Entity_Table_Size : constant := 4093;
197 -- Number of headers in hash table
199 subtype Entity_Header_Num is Integer range 0 .. Entity_Table_Size - 1;
200 -- Range of headers in hash table
202 function Node_Hash (Id : Entity_Id) return Entity_Header_Num;
203 -- Simple hash function for Entity_Ids
205 package Subprogram_Table is new GNAT.Htable.Simple_HTable
206 (Header_Num => Entity_Header_Num,
212 -- Hash table to record which subprograms are referenced. It is declared
213 -- at library level to avoid elaborating it for every call to Analyze.
215 package Traversed_Table is new GNAT.Htable.Simple_HTable
216 (Header_Num => Entity_Header_Num,
222 -- Hash table to record which nodes we have traversed, so we can avoid
223 -- traversing the same nodes repeatedly.
229 function Node_Hash (Id : Entity_Id) return Entity_Header_Num is
231 return Entity_Header_Num (Id mod Entity_Table_Size);
234 ---------------------------------
235 -- Analyze_Package_Body_Helper --
236 ---------------------------------
238 -- WARNING: This routine manages Ghost regions. Return statements must be
239 -- replaced by gotos which jump to the end of the routine and restore the
242 procedure Analyze_Package_Body_Helper (N : Node_Id) is
243 procedure Hide_Public_Entities (Decls : List_Id);
244 -- Attempt to hide all public entities found in declarative list Decls
245 -- by resetting their Is_Public flag to False depending on whether the
246 -- entities are not referenced by inlined or generic bodies. This kind
247 -- of processing is a conservative approximation and will still leave
248 -- entities externally visible if the package is not simple enough.
250 procedure Install_Composite_Operations (P : Entity_Id);
251 -- Composite types declared in the current scope may depend on types
252 -- that were private at the point of declaration, and whose full view
253 -- is now in scope. Indicate that the corresponding operations on the
254 -- composite type are available.
256 --------------------------
257 -- Hide_Public_Entities --
258 --------------------------
260 procedure Hide_Public_Entities (Decls : List_Id) is
261 function Has_Referencer
263 In_Nested_Instance : Boolean;
264 Has_Outer_Referencer_Of_Non_Subprograms : Boolean) return Boolean;
265 -- A "referencer" is a construct which may reference a previous
266 -- declaration. Examine all declarations in list Decls in reverse
267 -- and determine whether one such referencer exists. All entities
268 -- in the range Last (Decls) .. Referencer are hidden from external
271 function Scan_Subprogram_Ref (N : Node_Id) return Traverse_Result;
272 -- Determine whether a node denotes a reference to a subprogram
274 procedure Traverse_And_Scan_Subprogram_Refs is
275 new Traverse_Proc (Scan_Subprogram_Ref);
276 -- Subsidiary to routine Has_Referencer. Determine whether a node
277 -- contains references to a subprogram and record them.
278 -- WARNING: this is a very expensive routine as it performs a full
281 procedure Scan_Subprogram_Refs (Node : Node_Id);
282 -- If we haven't already traversed Node, then mark it and traverse
289 function Has_Referencer
291 In_Nested_Instance : Boolean;
292 Has_Outer_Referencer_Of_Non_Subprograms : Boolean) return Boolean
298 Has_Referencer_Of_Non_Subprograms : Boolean :=
299 Has_Outer_Referencer_Of_Non_Subprograms;
300 -- Set if an inlined subprogram body was detected as a referencer.
301 -- In this case, we do not return True immediately but keep hiding
302 -- subprograms from external visibility.
309 -- Examine all declarations in reverse order, hiding all entities
310 -- from external visibility until a referencer has been found. The
311 -- algorithm recurses into nested packages.
313 Decl := Last (Decls);
314 while Present (Decl) loop
316 -- A stub is always considered a referencer
318 if Nkind (Decl) in N_Body_Stub then
321 -- Package declaration
323 elsif Nkind (Decl) = N_Package_Declaration then
324 Spec := Specification (Decl);
325 Decl_Id := Defining_Entity (Spec);
327 -- Inspect the declarations of a non-generic package to try
328 -- and hide more entities from external visibility.
330 if not Is_Generic_Unit (Decl_Id) then
331 if Has_Referencer (Private_Declarations (Spec),
334 Is_Generic_Instance (Decl_Id),
335 Has_Referencer_Of_Non_Subprograms)
337 Has_Referencer (Visible_Declarations (Spec),
340 Is_Generic_Instance (Decl_Id),
341 Has_Referencer_Of_Non_Subprograms)
349 elsif Nkind (Decl) = N_Package_Body
350 and then Present (Corresponding_Spec (Decl))
352 Decl_Id := Corresponding_Spec (Decl);
354 -- A generic package body is a referencer. It would seem
355 -- that we only have to consider generics that can be
356 -- exported, i.e. where the corresponding spec is the
357 -- spec of the current package, but because of nested
358 -- instantiations, a fully private generic body may export
359 -- other private body entities. Furthermore, regardless of
360 -- whether there was a previous inlined subprogram, (an
361 -- instantiation of) the generic package may reference any
362 -- entity declared before it.
364 if Is_Generic_Unit (Decl_Id) then
367 -- Inspect the declarations of a non-generic package body to
368 -- try and hide more entities from external visibility.
370 elsif Has_Referencer (Declarations (Decl),
373 Is_Generic_Instance (Decl_Id),
374 Has_Referencer_Of_Non_Subprograms)
381 elsif Nkind (Decl) = N_Subprogram_Body then
382 if Present (Corresponding_Spec (Decl)) then
383 Decl_Id := Corresponding_Spec (Decl);
385 -- A generic subprogram body acts as a referencer
387 if Is_Generic_Unit (Decl_Id) then
391 -- An inlined subprogram body acts as a referencer
392 -- unless we generate C code since inlining is then
393 -- handled by the C compiler.
395 -- Note that we test Has_Pragma_Inline here in addition
396 -- to Is_Inlined. We are doing this for a client, since
397 -- we are computing which entities should be public, and
398 -- it is the client who will decide if actual inlining
399 -- should occur, so we need to catch all cases where the
400 -- subprogram may be inlined by the client.
402 if not Generate_C_Code
403 and then (Is_Inlined (Decl_Id)
404 or else Has_Pragma_Inline (Decl_Id))
406 Has_Referencer_Of_Non_Subprograms := True;
408 -- Inspect the statements of the subprogram body
409 -- to determine whether the body references other
412 Scan_Subprogram_Refs (Decl);
415 -- Otherwise this is a stand alone subprogram body
418 Decl_Id := Defining_Entity (Decl);
420 -- An inlined subprogram body acts as a referencer
421 -- unless we generate C code since inlining is then
422 -- handled by the C compiler.
424 if not Generate_C_Code
425 and then (Is_Inlined (Decl_Id)
426 or else Has_Pragma_Inline (Decl_Id))
428 Has_Referencer_Of_Non_Subprograms := True;
430 -- Inspect the statements of the subprogram body
431 -- to determine whether the body references other
434 Scan_Subprogram_Refs (Decl);
436 -- Otherwise we can reset Is_Public right away
438 elsif not Subprogram_Table.Get (Decl_Id) then
439 Set_Is_Public (Decl_Id, False);
445 elsif Nkind (Decl) = N_Freeze_Entity then
448 pragma Unreferenced (Discard);
450 -- Inspect the actions to find references to subprograms.
451 -- We assume that the actions do not contain other kinds
452 -- of references and, therefore, we do not stop the scan
453 -- or set Has_Referencer_Of_Non_Subprograms here. Doing
454 -- it would pessimize common cases for which the actions
455 -- contain the declaration of an init procedure, since
456 -- such a procedure is automatically marked inline.
459 Has_Referencer (Actions (Decl),
461 Has_Referencer_Of_Non_Subprograms);
464 -- Exceptions, objects and renamings do not need to be public
465 -- if they are not followed by a construct which can reference
466 -- and export them. Likewise for subprograms but we work harder
467 -- for them to see whether they are referenced on an individual
468 -- basis by looking into the table of referenced subprograms.
469 -- But we cannot say anything for entities declared in nested
470 -- instances because instantiations are not done yet so the
471 -- bodies are not visible and could contain references to them.
472 elsif Nkind_In (Decl, N_Exception_Declaration,
473 N_Object_Declaration,
474 N_Object_Renaming_Declaration,
475 N_Subprogram_Declaration,
476 N_Subprogram_Renaming_Declaration)
478 Decl_Id := Defining_Entity (Decl);
480 if not In_Nested_Instance
481 and then not Is_Imported (Decl_Id)
482 and then not Is_Exported (Decl_Id)
483 and then No (Interface_Name (Decl_Id))
485 ((Nkind (Decl) /= N_Subprogram_Declaration
486 and then not Has_Referencer_Of_Non_Subprograms)
487 or else (Nkind (Decl) = N_Subprogram_Declaration
488 and then not Subprogram_Table.Get (Decl_Id)))
490 Set_Is_Public (Decl_Id, False);
493 -- For a subprogram renaming, if the entity is referenced,
494 -- then so is the renamed subprogram. But there is an issue
495 -- with generic bodies because instantiations are not done
496 -- yet and, therefore, cannot be scanned for referencers.
497 -- That's why we use an approximation and test that we have
498 -- at least one subprogram referenced by an inlined body
499 -- instead of precisely the entity of this renaming.
501 if Nkind (Decl) = N_Subprogram_Renaming_Declaration
502 and then Subprogram_Table.Get_First
503 and then Is_Entity_Name (Name (Decl))
504 and then Present (Entity (Name (Decl)))
505 and then Is_Subprogram (Entity (Name (Decl)))
507 Subprogram_Table.Set (Entity (Name (Decl)), True);
514 return Has_Referencer_Of_Non_Subprograms;
517 -------------------------
518 -- Scan_Subprogram_Ref --
519 -------------------------
521 function Scan_Subprogram_Ref (N : Node_Id) return Traverse_Result is
523 -- Detect a reference of the form
526 if Nkind (N) in N_Subprogram_Call
527 and then Is_Entity_Name (Name (N))
528 and then Present (Entity (Name (N)))
529 and then Is_Subprogram (Entity (Name (N)))
531 Subprogram_Table.Set (Entity (Name (N)), True);
533 -- Detect a reference of the form
534 -- Subp'Some_Attribute
536 elsif Nkind (N) = N_Attribute_Reference
537 and then Is_Entity_Name (Prefix (N))
538 and then Present (Entity (Prefix (N)))
539 and then Is_Subprogram (Entity (Prefix (N)))
541 Subprogram_Table.Set (Entity (Prefix (N)), True);
543 -- Constants can be substituted by their value in gigi, which may
544 -- contain a reference, so scan the value recursively.
546 elsif Is_Entity_Name (N)
547 and then Present (Entity (N))
548 and then Ekind (Entity (N)) = E_Constant
551 Val : constant Node_Id := Constant_Value (Entity (N));
554 and then not Compile_Time_Known_Value (Val)
556 Scan_Subprogram_Refs (Val);
562 end Scan_Subprogram_Ref;
564 --------------------------
565 -- Scan_Subprogram_Refs --
566 --------------------------
568 procedure Scan_Subprogram_Refs (Node : Node_Id) is
570 if not Traversed_Table.Get (Node) then
571 Traversed_Table.Set (Node, True);
572 Traverse_And_Scan_Subprogram_Refs (Node);
574 end Scan_Subprogram_Refs;
579 pragma Unreferenced (Discard);
581 -- Start of processing for Hide_Public_Entities
584 -- The algorithm examines the top level declarations of a package
585 -- body in reverse looking for a construct that may export entities
586 -- declared prior to it. If such a scenario is encountered, then all
587 -- entities in the range Last (Decls) .. construct are hidden from
588 -- external visibility. Consider:
596 -- package body Pack is
597 -- External_Obj : ...; -- (1)
599 -- package body Gen is -- (2)
600 -- ... External_Obj ... -- (3)
603 -- Local_Obj : ...; -- (4)
606 -- In this example Local_Obj (4) must not be externally visible as
607 -- it cannot be exported by anything in Pack. The body of generic
608 -- package Gen (2) on the other hand acts as a "referencer" and may
609 -- export anything declared before it. Since the compiler does not
610 -- perform flow analysis, it is not possible to determine precisely
611 -- which entities will be exported when Gen is instantiated. In the
612 -- example above External_Obj (1) is exported at (3), but this may
613 -- not always be the case. The algorithm takes a conservative stance
614 -- and leaves entity External_Obj public.
616 -- This very conservative algorithm is supplemented by a more precise
617 -- processing for inlined bodies. For them, we traverse the syntactic
618 -- tree and record which subprograms are actually referenced from it.
619 -- This makes it possible to compute a much smaller set of externally
620 -- visible subprograms in the absence of generic bodies, which can
621 -- have a significant impact on the inlining decisions made in the
622 -- back end and the removal of out-of-line bodies from the object
623 -- code. We do it only for inlined bodies because they are supposed
624 -- to be reasonably small and tree traversal is very expensive.
626 -- Note that even this special processing is not optimal for inlined
627 -- bodies, because we treat all inlined subprograms alike. An optimal
628 -- algorithm would require computing the transitive closure of the
629 -- inlined subprograms that can really be referenced from other units
630 -- in the source code.
632 -- We could extend this processing for inlined bodies and record all
633 -- entities, not just subprograms, referenced from them, which would
634 -- make it possible to compute a much smaller set of all externally
635 -- visible entities in the absence of generic bodies. But this would
636 -- mean implementing a more thorough tree traversal of the bodies,
637 -- i.e. not just syntactic, and the gain would very likely be worth
638 -- neither the hassle nor the slowdown of the compiler.
640 -- Finally, an important thing to be aware of is that, at this point,
641 -- instantiations are not done yet so we cannot directly see inlined
642 -- bodies coming from them. That's not catastrophic because only the
643 -- actual parameters of the instantiations matter here, and they are
644 -- present in the declarations list of the instantiated packages.
646 Traversed_Table.Reset;
647 Subprogram_Table.Reset;
648 Discard := Has_Referencer (Decls, False, False);
649 end Hide_Public_Entities;
651 ----------------------------------
652 -- Install_Composite_Operations --
653 ----------------------------------
655 procedure Install_Composite_Operations (P : Entity_Id) is
659 Id := First_Entity (P);
660 while Present (Id) loop
662 and then (Is_Limited_Composite (Id)
663 or else Is_Private_Composite (Id))
664 and then No (Private_Component (Id))
666 Set_Is_Limited_Composite (Id, False);
667 Set_Is_Private_Composite (Id, False);
672 end Install_Composite_Operations;
676 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
677 Saved_IGR : constant Node_Id := Ignored_Ghost_Region;
678 Saved_EA : constant Boolean := Expander_Active;
679 Saved_ISMP : constant Boolean :=
680 Ignore_SPARK_Mode_Pragmas_In_Instance;
681 -- Save the Ghost and SPARK mode-related data to restore on exit
685 Last_Spec_Entity : Entity_Id;
690 -- Start of processing for Analyze_Package_Body_Helper
693 -- Find corresponding package specification, and establish the current
694 -- scope. The visible defining entity for the package is the defining
695 -- occurrence in the spec. On exit from the package body, all body
696 -- declarations are attached to the defining entity for the body, but
697 -- the later is never used for name resolution. In this fashion there
698 -- is only one visible entity that denotes the package.
700 -- Set Body_Id. Note that this will be reset to point to the generic
701 -- copy later on in the generic case.
703 Body_Id := Defining_Entity (N);
705 -- Body is body of package instantiation. Corresponding spec has already
708 if Present (Corresponding_Spec (N)) then
709 Spec_Id := Corresponding_Spec (N);
710 Pack_Decl := Unit_Declaration_Node (Spec_Id);
713 Spec_Id := Current_Entity_In_Scope (Defining_Entity (N));
716 and then Is_Package_Or_Generic_Package (Spec_Id)
718 Pack_Decl := Unit_Declaration_Node (Spec_Id);
720 if Nkind (Pack_Decl) = N_Package_Renaming_Declaration then
721 Error_Msg_N ("cannot supply body for package renaming", N);
724 elsif Present (Corresponding_Body (Pack_Decl)) then
725 Error_Msg_N ("redefinition of package body", N);
730 Error_Msg_N ("missing specification for package body", N);
734 if Is_Package_Or_Generic_Package (Spec_Id)
735 and then (Scope (Spec_Id) = Standard_Standard
736 or else Is_Child_Unit (Spec_Id))
737 and then not Unit_Requires_Body (Spec_Id)
739 if Ada_Version = Ada_83 then
741 ("optional package body (not allowed in Ada 95)??", N);
743 Error_Msg_N ("spec of this package does not allow a body", N);
748 -- A [generic] package body freezes the contract of the nearest
749 -- enclosing package body and all other contracts encountered in
750 -- the same declarative part up to and excluding the package body:
752 -- package body Nearest_Enclosing_Package
753 -- with Refined_State => (State => Constit)
757 -- package body Freezes_Enclosing_Package_Body
758 -- with Refined_State => (State_2 => Constit_2)
763 -- with Refined_Depends => (Input => (Constit, Constit_2)) ...
765 -- This ensures that any annotations referenced by the contract of a
766 -- [generic] subprogram body declared within the current package body
767 -- are available. This form of freezing is decoupled from the usual
768 -- Freeze_xxx mechanism because it must also work in the context of
769 -- generics where normal freezing is disabled.
771 -- Only bodies coming from source should cause this type of freezing.
772 -- Instantiated generic bodies are excluded because their processing is
773 -- performed in a separate compilation pass which lacks enough semantic
774 -- information with respect to contract analysis. It is safe to suppress
775 -- the freezing of contracts in this case because this action already
776 -- took place at the end of the enclosing declarative part.
778 if Comes_From_Source (N)
779 and then not Is_Generic_Instance (Spec_Id)
781 Freeze_Previous_Contracts (N);
784 -- A package body is Ghost when the corresponding spec is Ghost. Set
785 -- the mode now to ensure that any nodes generated during analysis and
786 -- expansion are properly flagged as ignored Ghost.
788 Mark_And_Set_Ghost_Body (N, Spec_Id);
790 -- Deactivate expansion inside the body of ignored Ghost entities,
791 -- as this code will ultimately be ignored. This avoids requiring the
792 -- presence of run-time units which are not needed. Only do this for
793 -- user entities, as internally generated entities might still need
794 -- to be expanded (e.g. those generated for types).
796 if Present (Ignored_Ghost_Region)
797 and then Comes_From_Source (Body_Id)
799 Expander_Active := False;
802 -- If the body completes the initial declaration of a compilation unit
803 -- which is subject to pragma Elaboration_Checks, set the model of the
804 -- pragma because it applies to all parts of the unit.
806 Install_Elaboration_Model (Spec_Id);
808 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
809 Style.Check_Identifier (Body_Id, Spec_Id);
811 if Is_Child_Unit (Spec_Id) then
812 if Nkind (Parent (N)) /= N_Compilation_Unit then
814 ("body of child unit& cannot be an inner package", N, Spec_Id);
817 Set_Is_Child_Unit (Body_Id);
820 -- Generic package case
822 if Ekind (Spec_Id) = E_Generic_Package then
824 -- Disable expansion and perform semantic analysis on copy. The
825 -- unannotated body will be used in all instantiations.
827 Body_Id := Defining_Entity (N);
828 Set_Ekind (Body_Id, E_Package_Body);
829 Set_Scope (Body_Id, Scope (Spec_Id));
830 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
831 Set_Body_Entity (Spec_Id, Body_Id);
832 Set_Spec_Entity (Body_Id, Spec_Id);
834 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
837 -- Once the contents of the generic copy and the template are
838 -- swapped, do the same for their respective aspect specifications.
840 Exchange_Aspects (N, New_N);
842 -- Collect all contract-related source pragmas found within the
843 -- template and attach them to the contract of the package body.
844 -- This contract is used in the capture of global references within
847 Create_Generic_Contract (N);
849 -- Update Body_Id to point to the copied node for the remainder of
852 Body_Id := Defining_Entity (N);
856 -- The Body_Id is that of the copied node in the generic case, the
857 -- current node otherwise. Note that N was rewritten above, so we must
858 -- be sure to get the latest Body_Id value.
860 Set_Ekind (Body_Id, E_Package_Body);
861 Set_Body_Entity (Spec_Id, Body_Id);
862 Set_Spec_Entity (Body_Id, Spec_Id);
864 -- Defining name for the package body is not a visible entity: Only the
865 -- defining name for the declaration is visible.
867 Set_Etype (Body_Id, Standard_Void_Type);
868 Set_Scope (Body_Id, Scope (Spec_Id));
869 Set_Corresponding_Spec (N, Spec_Id);
870 Set_Corresponding_Body (Pack_Decl, Body_Id);
872 -- The body entity is not used for semantics or code generation, but
873 -- it is attached to the entity list of the enclosing scope to simplify
874 -- the listing of back-annotations for the types it main contain.
876 if Scope (Spec_Id) /= Standard_Standard then
877 Append_Entity (Body_Id, Scope (Spec_Id));
880 -- Indicate that we are currently compiling the body of the package
882 Set_In_Package_Body (Spec_Id);
883 Set_Has_Completion (Spec_Id);
884 Last_Spec_Entity := Last_Entity (Spec_Id);
886 if Has_Aspects (N) then
887 Analyze_Aspect_Specifications (N, Body_Id);
890 Push_Scope (Spec_Id);
892 -- Set SPARK_Mode only for non-generic package
894 if Ekind (Spec_Id) = E_Package then
895 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
896 Set_SPARK_Aux_Pragma (Body_Id, SPARK_Mode_Pragma);
897 Set_SPARK_Pragma_Inherited (Body_Id);
898 Set_SPARK_Aux_Pragma_Inherited (Body_Id);
900 -- A package body may be instantiated or inlined at a later pass.
901 -- Restore the state of Ignore_SPARK_Mode_Pragmas_In_Instance when
902 -- it applied to the package spec.
904 if Ignore_SPARK_Mode_Pragmas (Spec_Id) then
905 Ignore_SPARK_Mode_Pragmas_In_Instance := True;
909 Set_Categorization_From_Pragmas (N);
911 Install_Visible_Declarations (Spec_Id);
912 Install_Private_Declarations (Spec_Id);
913 Install_Private_With_Clauses (Spec_Id);
914 Install_Composite_Operations (Spec_Id);
916 Check_Anonymous_Access_Types (Spec_Id, N);
918 if Ekind (Spec_Id) = E_Generic_Package then
919 Set_Use (Generic_Formal_Declarations (Pack_Decl));
922 Set_Use (Visible_Declarations (Specification (Pack_Decl)));
923 Set_Use (Private_Declarations (Specification (Pack_Decl)));
925 -- This is a nested package, so it may be necessary to declare certain
926 -- inherited subprograms that are not yet visible because the parent
927 -- type's subprograms are now visible.
928 -- Note that for child units these operations were generated when
929 -- analyzing the package specification.
931 if Ekind (Scope (Spec_Id)) = E_Package
932 and then Scope (Spec_Id) /= Standard_Standard
933 and then not Is_Child_Unit (Spec_Id)
935 Declare_Inherited_Private_Subprograms (Spec_Id);
938 if Present (Declarations (N)) then
939 Analyze_Declarations (Declarations (N));
940 Inspect_Deferred_Constant_Completion (Declarations (N));
943 -- Verify that the SPARK_Mode of the body agrees with that of its spec
945 if Present (SPARK_Pragma (Body_Id)) then
946 if Present (SPARK_Aux_Pragma (Spec_Id)) then
947 if Get_SPARK_Mode_From_Annotation (SPARK_Aux_Pragma (Spec_Id)) =
950 Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Body_Id)) = On
952 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
953 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
954 Error_Msg_Sloc := Sloc (SPARK_Aux_Pragma (Spec_Id));
956 ("\value Off was set for SPARK_Mode on & #", N, Spec_Id);
960 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
961 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
962 Error_Msg_Sloc := Sloc (Spec_Id);
964 ("\no value was set for SPARK_Mode on & #", N, Spec_Id);
968 -- Analyze_Declarations has caused freezing of all types. Now generate
969 -- bodies for RACW primitives and stream attributes, if any.
971 if Ekind (Spec_Id) = E_Package and then Has_RACW (Spec_Id) then
973 -- Attach subprogram bodies to support RACWs declared in spec
975 Append_RACW_Bodies (Declarations (N), Spec_Id);
976 Analyze_List (Declarations (N));
979 HSS := Handled_Statement_Sequence (N);
981 if Present (HSS) then
982 Process_End_Label (HSS, 't', Spec_Id);
985 -- Check that elaboration code in a preelaborable package body is
986 -- empty other than null statements and labels (RM 10.2.1(6)).
988 Validate_Null_Statement_Sequence (N);
991 Validate_Categorization_Dependency (N, Spec_Id);
992 Check_Completion (Body_Id);
994 -- Generate start of body reference. Note that we do this fairly late,
995 -- because the call will use In_Extended_Main_Source_Unit as a check,
996 -- and we want to make sure that Corresponding_Stub links are set
998 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
1000 -- For a generic package, collect global references and mark them on
1001 -- the original body so that they are not resolved again at the point
1002 -- of instantiation.
1004 if Ekind (Spec_Id) /= E_Package then
1005 Save_Global_References (Original_Node (N));
1009 -- The entities of the package body have so far been chained onto the
1010 -- declaration chain for the spec. That's been fine while we were in the
1011 -- body, since we wanted them to be visible, but now that we are leaving
1012 -- the package body, they are no longer visible, so we remove them from
1013 -- the entity chain of the package spec entity, and copy them to the
1014 -- entity chain of the package body entity, where they will never again
1017 if Present (Last_Spec_Entity) then
1018 Set_First_Entity (Body_Id, Next_Entity (Last_Spec_Entity));
1019 Set_Next_Entity (Last_Spec_Entity, Empty);
1020 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
1021 Set_Last_Entity (Spec_Id, Last_Spec_Entity);
1024 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
1025 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
1026 Set_First_Entity (Spec_Id, Empty);
1027 Set_Last_Entity (Spec_Id, Empty);
1030 Update_Use_Clause_Chain;
1031 End_Package_Scope (Spec_Id);
1033 -- All entities declared in body are not visible
1039 E := First_Entity (Body_Id);
1040 while Present (E) loop
1041 Set_Is_Immediately_Visible (E, False);
1042 Set_Is_Potentially_Use_Visible (E, False);
1045 -- Child units may appear on the entity list (e.g. if they appear
1046 -- in the context of a subunit) but they are not body entities.
1048 if not Is_Child_Unit (E) then
1049 Set_Is_Package_Body_Entity (E);
1056 Check_References (Body_Id);
1058 -- For a generic unit, check that the formal parameters are referenced,
1059 -- and that local variables are used, as for regular packages.
1061 if Ekind (Spec_Id) = E_Generic_Package then
1062 Check_References (Spec_Id);
1065 -- At this point all entities of the package body are externally visible
1066 -- to the linker as their Is_Public flag is set to True. This proactive
1067 -- approach is necessary because an inlined or a generic body for which
1068 -- code is generated in other units may need to see these entities. Cut
1069 -- down the number of global symbols that do not need public visibility
1070 -- as this has two beneficial effects:
1071 -- (1) It makes the compilation process more efficient.
1072 -- (2) It gives the code generator more leeway to optimize within each
1073 -- unit, especially subprograms.
1075 -- This is done only for top-level library packages or child units as
1076 -- the algorithm does a top-down traversal of the package body.
1078 if (Scope (Spec_Id) = Standard_Standard or else Is_Child_Unit (Spec_Id))
1079 and then not Is_Generic_Unit (Spec_Id)
1081 Hide_Public_Entities (Declarations (N));
1084 -- If expander is not active, then here is where we turn off the
1085 -- In_Package_Body flag, otherwise it is turned off at the end of the
1086 -- corresponding expansion routine. If this is an instance body, we need
1087 -- to qualify names of local entities, because the body may have been
1088 -- compiled as a preliminary to another instantiation.
1090 if not Expander_Active then
1091 Set_In_Package_Body (Spec_Id, False);
1093 if Is_Generic_Instance (Spec_Id)
1094 and then Operating_Mode = Generate_Code
1096 Qualify_Entity_Names (N);
1100 if Present (Ignored_Ghost_Region) then
1101 Expander_Active := Saved_EA;
1104 Ignore_SPARK_Mode_Pragmas_In_Instance := Saved_ISMP;
1105 Restore_Ghost_Region (Saved_GM, Saved_IGR);
1106 end Analyze_Package_Body_Helper;
1108 ---------------------------------
1109 -- Analyze_Package_Declaration --
1110 ---------------------------------
1112 procedure Analyze_Package_Declaration (N : Node_Id) is
1113 Id : constant Node_Id := Defining_Entity (N);
1115 Is_Comp_Unit : constant Boolean :=
1116 Nkind (Parent (N)) = N_Compilation_Unit;
1118 Body_Required : Boolean;
1119 -- True when this package declaration requires a corresponding body
1122 if Debug_Flag_C then
1123 Write_Str ("==> package spec ");
1124 Write_Name (Chars (Id));
1125 Write_Str (" from ");
1126 Write_Location (Sloc (N));
1131 Generate_Definition (Id);
1133 Set_Ekind (Id, E_Package);
1134 Set_Etype (Id, Standard_Void_Type);
1136 -- Set SPARK_Mode from context
1138 Set_SPARK_Pragma (Id, SPARK_Mode_Pragma);
1139 Set_SPARK_Aux_Pragma (Id, SPARK_Mode_Pragma);
1140 Set_SPARK_Pragma_Inherited (Id);
1141 Set_SPARK_Aux_Pragma_Inherited (Id);
1143 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in case
1144 -- the body of this package is instantiated or inlined later and out of
1145 -- context. The body uses this attribute to restore the value of the
1148 if Ignore_SPARK_Mode_Pragmas_In_Instance then
1149 Set_Ignore_SPARK_Mode_Pragmas (Id);
1152 -- Analyze aspect specifications immediately, since we need to recognize
1153 -- things like Pure early enough to diagnose violations during analysis.
1155 if Has_Aspects (N) then
1156 Analyze_Aspect_Specifications (N, Id);
1159 -- Ada 2005 (AI-217): Check if the package has been illegally named in
1160 -- a limited-with clause of its own context. In this case the error has
1161 -- been previously notified by Analyze_Context.
1163 -- limited with Pkg; -- ERROR
1164 -- package Pkg is ...
1166 if From_Limited_With (Id) then
1172 Set_Is_Pure (Id, Is_Pure (Enclosing_Lib_Unit_Entity));
1173 Set_Categorization_From_Pragmas (N);
1175 Analyze (Specification (N));
1176 Validate_Categorization_Dependency (N, Id);
1178 -- Determine whether the package requires a body. Abstract states are
1179 -- intentionally ignored because they do require refinement which can
1180 -- only come in a body, but at the same time they do not force the need
1181 -- for a body on their own (SPARK RM 7.1.4(4) and 7.2.2(3)).
1183 Body_Required := Unit_Requires_Body (Id);
1185 if not Body_Required then
1187 -- If the package spec does not require an explicit body, then there
1188 -- are not entities requiring completion in the language sense. Call
1189 -- Check_Completion now to ensure that nested package declarations
1190 -- that require an implicit body get one. (In the case where a body
1191 -- is required, Check_Completion is called at the end of the body's
1192 -- declarative part.)
1196 -- If the package spec does not require an explicit body, then all
1197 -- abstract states declared in nested packages cannot possibly get
1198 -- a proper refinement (SPARK RM 7.2.2(3)). This check is performed
1199 -- only when the compilation unit is the main unit to allow for
1200 -- modular SPARK analysis where packages do not necessarily have
1203 if Is_Comp_Unit then
1204 Check_State_Refinements
1206 Is_Main_Unit => Parent (N) = Cunit (Main_Unit));
1210 -- Set Body_Required indication on the compilation unit node
1212 if Is_Comp_Unit then
1213 Set_Body_Required (Parent (N), Body_Required);
1215 if Legacy_Elaboration_Checks and not Body_Required then
1216 Set_Suppress_Elaboration_Warnings (Id);
1220 End_Package_Scope (Id);
1222 -- For the declaration of a library unit that is a remote types package,
1223 -- check legality rules regarding availability of stream attributes for
1224 -- types that contain non-remote access values. This subprogram performs
1225 -- visibility tests that rely on the fact that we have exited the scope
1228 if Is_Comp_Unit then
1229 Validate_RT_RAT_Component (N);
1232 if Debug_Flag_C then
1234 Write_Str ("<== package spec ");
1235 Write_Name (Chars (Id));
1236 Write_Str (" from ");
1237 Write_Location (Sloc (N));
1240 end Analyze_Package_Declaration;
1242 -----------------------------------
1243 -- Analyze_Package_Specification --
1244 -----------------------------------
1246 -- Note that this code is shared for the analysis of generic package specs
1247 -- (see Sem_Ch12.Analyze_Generic_Package_Declaration for details).
1249 procedure Analyze_Package_Specification (N : Node_Id) is
1250 Id : constant Entity_Id := Defining_Entity (N);
1251 Orig_Decl : constant Node_Id := Original_Node (Parent (N));
1252 Vis_Decls : constant List_Id := Visible_Declarations (N);
1253 Priv_Decls : constant List_Id := Private_Declarations (N);
1256 Public_Child : Boolean;
1258 Private_With_Clauses_Installed : Boolean := False;
1259 -- In Ada 2005, private with_clauses are visible in the private part
1260 -- of a nested package, even if it appears in the public part of the
1261 -- enclosing package. This requires a separate step to install these
1262 -- private_with_clauses, and remove them at the end of the nested
1265 procedure Check_One_Tagged_Type_Or_Extension_At_Most;
1266 -- Issue an error in SPARK mode if a package specification contains
1267 -- more than one tagged type or type extension.
1269 procedure Clear_Constants (Id : Entity_Id; FE : Entity_Id);
1270 -- Clears constant indications (Never_Set_In_Source, Constant_Value, and
1271 -- Is_True_Constant) on all variables that are entities of Id, and on
1272 -- the chain whose first element is FE. A recursive call is made for all
1273 -- packages and generic packages.
1275 procedure Generate_Parent_References;
1276 -- For a child unit, generate references to parent units, for
1277 -- GNAT Studio navigation purposes.
1279 function Is_Public_Child (Child, Unit : Entity_Id) return Boolean;
1280 -- Child and Unit are entities of compilation units. True if Child
1281 -- is a public child of Parent as defined in 10.1.1
1283 procedure Inspect_Unchecked_Union_Completion (Decls : List_Id);
1284 -- Reject completion of an incomplete or private type declarations
1285 -- having a known discriminant part by an unchecked union.
1287 procedure Install_Parent_Private_Declarations (Inst_Id : Entity_Id);
1288 -- Given the package entity of a generic package instantiation or
1289 -- formal package whose corresponding generic is a child unit, installs
1290 -- the private declarations of each of the child unit's parents.
1291 -- This has to be done at the point of entering the instance package's
1292 -- private part rather than being done in Sem_Ch12.Install_Parent
1293 -- (which is where the parents' visible declarations are installed).
1295 ------------------------------------------------
1296 -- Check_One_Tagged_Type_Or_Extension_At_Most --
1297 ------------------------------------------------
1299 procedure Check_One_Tagged_Type_Or_Extension_At_Most is
1302 procedure Check_Decls (Decls : List_Id);
1303 -- Check that either Previous is Empty and Decls does not contain
1304 -- more than one tagged type or type extension, or Previous is
1305 -- already set and Decls contains no tagged type or type extension.
1311 procedure Check_Decls (Decls : List_Id) is
1315 Decl := First (Decls);
1316 while Present (Decl) loop
1317 if Nkind (Decl) = N_Full_Type_Declaration
1318 and then Is_Tagged_Type (Defining_Identifier (Decl))
1320 if No (Previous) then
1324 Error_Msg_Sloc := Sloc (Previous);
1325 Check_SPARK_05_Restriction
1326 ("at most one tagged type or type extension allowed",
1327 "\\ previous declaration#",
1336 -- Start of processing for Check_One_Tagged_Type_Or_Extension_At_Most
1340 Check_Decls (Vis_Decls);
1342 if Present (Priv_Decls) then
1343 Check_Decls (Priv_Decls);
1345 end Check_One_Tagged_Type_Or_Extension_At_Most;
1347 ---------------------
1348 -- Clear_Constants --
1349 ---------------------
1351 procedure Clear_Constants (Id : Entity_Id; FE : Entity_Id) is
1355 -- Ignore package renamings, not interesting and they can cause self
1356 -- referential loops in the code below.
1358 if Nkind (Parent (Id)) = N_Package_Renaming_Declaration then
1362 -- Note: in the loop below, the check for Next_Entity pointing back
1363 -- to the package entity may seem odd, but it is needed, because a
1364 -- package can contain a renaming declaration to itself, and such
1365 -- renamings are generated automatically within package instances.
1368 while Present (E) and then E /= Id loop
1369 if Is_Assignable (E) then
1370 Set_Never_Set_In_Source (E, False);
1371 Set_Is_True_Constant (E, False);
1372 Set_Current_Value (E, Empty);
1373 Set_Is_Known_Null (E, False);
1374 Set_Last_Assignment (E, Empty);
1376 if not Can_Never_Be_Null (E) then
1377 Set_Is_Known_Non_Null (E, False);
1380 elsif Is_Package_Or_Generic_Package (E) then
1381 Clear_Constants (E, First_Entity (E));
1382 Clear_Constants (E, First_Private_Entity (E));
1387 end Clear_Constants;
1389 --------------------------------
1390 -- Generate_Parent_References --
1391 --------------------------------
1393 procedure Generate_Parent_References is
1394 Decl : constant Node_Id := Parent (N);
1397 if Id = Cunit_Entity (Main_Unit)
1398 or else Parent (Decl) = Library_Unit (Cunit (Main_Unit))
1400 Generate_Reference (Id, Scope (Id), 'k', False);
1402 elsif not Nkind_In (Unit (Cunit (Main_Unit)), N_Subprogram_Body,
1405 -- If current unit is an ancestor of main unit, generate a
1406 -- reference to its own parent.
1410 Main_Spec : Node_Id := Unit (Cunit (Main_Unit));
1413 if Nkind (Main_Spec) = N_Package_Body then
1414 Main_Spec := Unit (Library_Unit (Cunit (Main_Unit)));
1417 U := Parent_Spec (Main_Spec);
1418 while Present (U) loop
1419 if U = Parent (Decl) then
1420 Generate_Reference (Id, Scope (Id), 'k', False);
1423 elsif Nkind (Unit (U)) = N_Package_Body then
1427 U := Parent_Spec (Unit (U));
1432 end Generate_Parent_References;
1434 ---------------------
1435 -- Is_Public_Child --
1436 ---------------------
1438 function Is_Public_Child (Child, Unit : Entity_Id) return Boolean is
1440 if not Is_Private_Descendant (Child) then
1443 if Child = Unit then
1444 return not Private_Present (
1445 Parent (Unit_Declaration_Node (Child)));
1447 return Is_Public_Child (Scope (Child), Unit);
1450 end Is_Public_Child;
1452 ----------------------------------------
1453 -- Inspect_Unchecked_Union_Completion --
1454 ----------------------------------------
1456 procedure Inspect_Unchecked_Union_Completion (Decls : List_Id) is
1460 Decl := First (Decls);
1461 while Present (Decl) loop
1463 -- We are looking at an incomplete or private type declaration
1464 -- with a known_discriminant_part whose full view is an
1465 -- Unchecked_Union. The seemingly useless check with Is_Type
1466 -- prevents cascaded errors when routines defined only for type
1467 -- entities are called with non-type entities.
1469 if Nkind_In (Decl, N_Incomplete_Type_Declaration,
1470 N_Private_Type_Declaration)
1471 and then Is_Type (Defining_Identifier (Decl))
1472 and then Has_Discriminants (Defining_Identifier (Decl))
1473 and then Present (Full_View (Defining_Identifier (Decl)))
1475 Is_Unchecked_Union (Full_View (Defining_Identifier (Decl)))
1478 ("completion of discriminated partial view "
1479 & "cannot be an unchecked union",
1480 Full_View (Defining_Identifier (Decl)));
1485 end Inspect_Unchecked_Union_Completion;
1487 -----------------------------------------
1488 -- Install_Parent_Private_Declarations --
1489 -----------------------------------------
1491 procedure Install_Parent_Private_Declarations (Inst_Id : Entity_Id) is
1492 Inst_Par : Entity_Id;
1493 Gen_Par : Entity_Id;
1494 Inst_Node : Node_Id;
1497 Inst_Par := Inst_Id;
1500 Generic_Parent (Specification (Unit_Declaration_Node (Inst_Par)));
1501 while Present (Gen_Par) and then Is_Child_Unit (Gen_Par) loop
1502 Inst_Node := Get_Unit_Instantiation_Node (Inst_Par);
1504 if Nkind_In (Inst_Node, N_Package_Instantiation,
1505 N_Formal_Package_Declaration)
1506 and then Nkind (Name (Inst_Node)) = N_Expanded_Name
1508 Inst_Par := Entity (Prefix (Name (Inst_Node)));
1510 if Present (Renamed_Entity (Inst_Par)) then
1511 Inst_Par := Renamed_Entity (Inst_Par);
1514 -- The instance may appear in a sibling generic unit, in
1515 -- which case the prefix must include the common (generic)
1516 -- ancestor, which is treated as a current instance.
1519 and then Ekind (Inst_Par) = E_Generic_Package
1521 Gen_Par := Inst_Par;
1522 pragma Assert (In_Open_Scopes (Gen_Par));
1527 (Specification (Unit_Declaration_Node (Inst_Par)));
1530 -- Install the private declarations and private use clauses
1531 -- of a parent instance of the child instance, unless the
1532 -- parent instance private declarations have already been
1533 -- installed earlier in Analyze_Package_Specification, which
1534 -- happens when a generic child is instantiated, and the
1535 -- instance is a child of the parent instance.
1537 -- Installing the use clauses of the parent instance twice
1538 -- is both unnecessary and wrong, because it would cause the
1539 -- clauses to be chained to themselves in the use clauses
1540 -- list of the scope stack entry. That in turn would cause
1541 -- an endless loop from End_Use_Clauses upon scope exit.
1543 -- The parent is now fully visible. It may be a hidden open
1544 -- scope if we are currently compiling some child instance
1545 -- declared within it, but while the current instance is being
1546 -- compiled the parent is immediately visible. In particular
1547 -- its entities must remain visible if a stack save/restore
1548 -- takes place through a call to Rtsfind.
1550 if Present (Gen_Par) then
1551 if not In_Private_Part (Inst_Par) then
1552 Install_Private_Declarations (Inst_Par);
1553 Set_Use (Private_Declarations
1555 (Unit_Declaration_Node (Inst_Par))));
1556 Set_Is_Hidden_Open_Scope (Inst_Par, False);
1559 -- If we've reached the end of the generic instance parents,
1560 -- then finish off by looping through the nongeneric parents
1561 -- and installing their private declarations.
1563 -- If one of the non-generic parents is itself on the scope
1564 -- stack, do not install its private declarations: they are
1565 -- installed in due time when the private part of that parent
1569 while Present (Inst_Par)
1570 and then Inst_Par /= Standard_Standard
1571 and then (not In_Open_Scopes (Inst_Par)
1572 or else not In_Private_Part (Inst_Par))
1574 if Nkind (Inst_Node) = N_Formal_Package_Declaration
1576 not Is_Ancestor_Package
1577 (Inst_Par, Cunit_Entity (Current_Sem_Unit))
1579 Install_Private_Declarations (Inst_Par);
1581 (Private_Declarations
1583 (Unit_Declaration_Node (Inst_Par))));
1584 Inst_Par := Scope (Inst_Par);
1597 end Install_Parent_Private_Declarations;
1599 -- Start of processing for Analyze_Package_Specification
1602 if Present (Vis_Decls) then
1603 Analyze_Declarations (Vis_Decls);
1606 -- Inspect the entities defined in the package and ensure that all
1607 -- incomplete types have received full declarations. Build default
1608 -- initial condition and invariant procedures for all qualifying types.
1610 E := First_Entity (Id);
1611 while Present (E) loop
1613 -- Check on incomplete types
1615 -- AI05-0213: A formal incomplete type has no completion, and neither
1616 -- does the corresponding subtype in an instance.
1618 if Is_Incomplete_Type (E)
1619 and then No (Full_View (E))
1620 and then not Is_Generic_Type (E)
1621 and then not From_Limited_With (E)
1622 and then not Is_Generic_Actual_Type (E)
1624 Error_Msg_N ("no declaration in visible part for incomplete}", E);
1630 if Is_Remote_Call_Interface (Id)
1631 and then Nkind (Parent (Parent (N))) = N_Compilation_Unit
1633 Validate_RCI_Declarations (Id);
1636 -- Save global references in the visible declarations, before installing
1637 -- private declarations of parent unit if there is one, because the
1638 -- privacy status of types defined in the parent will change. This is
1639 -- only relevant for generic child units, but is done in all cases for
1642 if Ekind (Id) = E_Generic_Package
1643 and then Nkind (Orig_Decl) = N_Generic_Package_Declaration
1646 Orig_Spec : constant Node_Id := Specification (Orig_Decl);
1647 Save_Priv : constant List_Id := Private_Declarations (Orig_Spec);
1650 -- Insert the freezing nodes after the visible declarations to
1651 -- ensure that we analyze its aspects; needed to ensure that
1652 -- global entities referenced in the aspects are properly handled.
1654 if Ada_Version >= Ada_2012
1655 and then Is_Non_Empty_List (Vis_Decls)
1656 and then Is_Empty_List (Priv_Decls)
1658 Insert_List_After_And_Analyze
1659 (Last (Vis_Decls), Freeze_Entity (Id, Last (Vis_Decls)));
1662 Set_Private_Declarations (Orig_Spec, Empty_List);
1663 Save_Global_References (Orig_Decl);
1664 Set_Private_Declarations (Orig_Spec, Save_Priv);
1668 -- If package is a public child unit, then make the private declarations
1669 -- of the parent visible.
1671 Public_Child := False;
1675 Pack_Decl : Node_Id;
1680 Par_Spec := Parent_Spec (Parent (N));
1682 -- If the package is formal package of an enclosing generic, it is
1683 -- transformed into a local generic declaration, and compiled to make
1684 -- its spec available. We need to retrieve the original generic to
1685 -- determine whether it is a child unit, and install its parents.
1689 Nkind (Original_Node (Parent (N))) = N_Formal_Package_Declaration
1691 Par := Entity (Name (Original_Node (Parent (N))));
1692 Par_Spec := Parent_Spec (Unit_Declaration_Node (Par));
1695 if Present (Par_Spec) then
1696 Generate_Parent_References;
1698 while Scope (Par) /= Standard_Standard
1699 and then Is_Public_Child (Id, Par)
1700 and then In_Open_Scopes (Par)
1702 Public_Child := True;
1704 Install_Private_Declarations (Par);
1705 Install_Private_With_Clauses (Par);
1706 Pack_Decl := Unit_Declaration_Node (Par);
1707 Set_Use (Private_Declarations (Specification (Pack_Decl)));
1712 if Is_Compilation_Unit (Id) then
1713 Install_Private_With_Clauses (Id);
1715 -- The current compilation unit may include private with_clauses,
1716 -- which are visible in the private part of the current nested
1717 -- package, and have to be installed now. This is not done for
1718 -- nested instantiations, where the private with_clauses of the
1719 -- enclosing unit have no effect once the instantiation info is
1720 -- established and we start analyzing the package declaration.
1723 Comp_Unit : constant Entity_Id := Cunit_Entity (Current_Sem_Unit);
1725 if Is_Package_Or_Generic_Package (Comp_Unit)
1726 and then not In_Private_Part (Comp_Unit)
1727 and then not In_Instance
1729 Install_Private_With_Clauses (Comp_Unit);
1730 Private_With_Clauses_Installed := True;
1735 -- If this is a package associated with a generic instance or formal
1736 -- package, then the private declarations of each of the generic's
1737 -- parents must be installed at this point.
1739 if Is_Generic_Instance (Id) then
1740 Install_Parent_Private_Declarations (Id);
1743 -- Analyze private part if present. The flag In_Private_Part is reset
1744 -- in End_Package_Scope.
1746 L := Last_Entity (Id);
1748 if Present (Priv_Decls) then
1749 Set_In_Private_Part (Id);
1751 -- Upon entering a public child's private part, it may be necessary
1752 -- to declare subprograms that were derived in the package's visible
1753 -- part but not yet made visible.
1755 if Public_Child then
1756 Declare_Inherited_Private_Subprograms (Id);
1759 Analyze_Declarations (Priv_Decls);
1761 -- Check the private declarations for incomplete deferred constants
1763 Inspect_Deferred_Constant_Completion (Priv_Decls);
1765 -- The first private entity is the immediate follower of the last
1766 -- visible entity, if there was one.
1769 Set_First_Private_Entity (Id, Next_Entity (L));
1771 Set_First_Private_Entity (Id, First_Entity (Id));
1774 -- There may be inherited private subprograms that need to be declared,
1775 -- even in the absence of an explicit private part. If there are any
1776 -- public declarations in the package and the package is a public child
1777 -- unit, then an implicit private part is assumed.
1779 elsif Present (L) and then Public_Child then
1780 Set_In_Private_Part (Id);
1781 Declare_Inherited_Private_Subprograms (Id);
1782 Set_First_Private_Entity (Id, Next_Entity (L));
1785 E := First_Entity (Id);
1786 while Present (E) loop
1788 -- Check rule of 3.6(11), which in general requires waiting till all
1789 -- full types have been seen.
1791 if Ekind (E) = E_Record_Type or else Ekind (E) = E_Array_Type then
1792 Check_Aliased_Component_Types (E);
1795 -- Check preelaborable initialization for full type completing a
1796 -- private type for which pragma Preelaborable_Initialization given.
1799 and then Must_Have_Preelab_Init (E)
1800 and then not Has_Preelaborable_Initialization (E)
1803 ("full view of & does not have preelaborable initialization", E);
1809 -- Ada 2005 (AI-216): The completion of an incomplete or private type
1810 -- declaration having a known_discriminant_part shall not be an
1811 -- unchecked union type.
1813 if Present (Vis_Decls) then
1814 Inspect_Unchecked_Union_Completion (Vis_Decls);
1817 if Present (Priv_Decls) then
1818 Inspect_Unchecked_Union_Completion (Priv_Decls);
1821 if Ekind (Id) = E_Generic_Package
1822 and then Nkind (Orig_Decl) = N_Generic_Package_Declaration
1823 and then Present (Priv_Decls)
1825 -- Save global references in private declarations, ignoring the
1826 -- visible declarations that were processed earlier.
1829 Orig_Spec : constant Node_Id := Specification (Orig_Decl);
1830 Save_Vis : constant List_Id := Visible_Declarations (Orig_Spec);
1831 Save_Form : constant List_Id :=
1832 Generic_Formal_Declarations (Orig_Decl);
1835 -- Insert the freezing nodes after the private declarations to
1836 -- ensure that we analyze its aspects; needed to ensure that
1837 -- global entities referenced in the aspects are properly handled.
1839 if Ada_Version >= Ada_2012
1840 and then Is_Non_Empty_List (Priv_Decls)
1842 Insert_List_After_And_Analyze
1843 (Last (Priv_Decls), Freeze_Entity (Id, Last (Priv_Decls)));
1846 Set_Visible_Declarations (Orig_Spec, Empty_List);
1847 Set_Generic_Formal_Declarations (Orig_Decl, Empty_List);
1848 Save_Global_References (Orig_Decl);
1849 Set_Generic_Formal_Declarations (Orig_Decl, Save_Form);
1850 Set_Visible_Declarations (Orig_Spec, Save_Vis);
1854 Process_End_Label (N, 'e', Id);
1856 -- Remove private_with_clauses of enclosing compilation unit, if they
1859 if Private_With_Clauses_Installed then
1860 Remove_Private_With_Clauses (Cunit (Current_Sem_Unit));
1863 -- For the case of a library level package, we must go through all the
1864 -- entities clearing the indications that the value may be constant and
1865 -- not modified. Why? Because any client of this package may modify
1866 -- these values freely from anywhere. This also applies to any nested
1867 -- packages or generic packages.
1869 -- For now we unconditionally clear constants for packages that are
1870 -- instances of generic packages. The reason is that we do not have the
1871 -- body yet, and we otherwise think things are unreferenced when they
1872 -- are not. This should be fixed sometime (the effect is not terrible,
1873 -- we just lose some warnings, and also some cases of value propagation)
1876 if Is_Library_Level_Entity (Id)
1877 or else Is_Generic_Instance (Id)
1879 Clear_Constants (Id, First_Entity (Id));
1880 Clear_Constants (Id, First_Private_Entity (Id));
1883 -- Issue an error in SPARK mode if a package specification contains
1884 -- more than one tagged type or type extension.
1886 Check_One_Tagged_Type_Or_Extension_At_Most;
1888 -- Output relevant information as to why the package requires a body.
1889 -- Do not consider generated packages as this exposes internal symbols
1890 -- and leads to confusing messages.
1892 if List_Body_Required_Info
1893 and then In_Extended_Main_Source_Unit (Id)
1894 and then Unit_Requires_Body (Id)
1895 and then Comes_From_Source (Id)
1897 Unit_Requires_Body_Info (Id);
1900 -- Nested package specs that do not require bodies are not checked for
1901 -- ineffective use clauses due to the possibility of subunits. This is
1902 -- because at this stage it is impossible to tell whether there will be
1905 if not Unit_Requires_Body (Id)
1906 and then Is_Compilation_Unit (Id)
1907 and then not Is_Private_Descendant (Id)
1909 Update_Use_Clause_Chain;
1911 end Analyze_Package_Specification;
1913 --------------------------------------
1914 -- Analyze_Private_Type_Declaration --
1915 --------------------------------------
1917 procedure Analyze_Private_Type_Declaration (N : Node_Id) is
1918 Id : constant Entity_Id := Defining_Identifier (N);
1919 PF : constant Boolean := Is_Pure (Enclosing_Lib_Unit_Entity);
1922 Generate_Definition (Id);
1923 Set_Is_Pure (Id, PF);
1924 Init_Size_Align (Id);
1926 if not Is_Package_Or_Generic_Package (Current_Scope)
1927 or else In_Private_Part (Current_Scope)
1929 Error_Msg_N ("invalid context for private declaration", N);
1932 New_Private_Type (N, Id, N);
1933 Set_Depends_On_Private (Id);
1935 -- Set the SPARK mode from the current context
1937 Set_SPARK_Pragma (Id, SPARK_Mode_Pragma);
1938 Set_SPARK_Pragma_Inherited (Id);
1940 if Has_Aspects (N) then
1941 Analyze_Aspect_Specifications (N, Id);
1943 end Analyze_Private_Type_Declaration;
1945 ----------------------------------
1946 -- Check_Anonymous_Access_Types --
1947 ----------------------------------
1949 procedure Check_Anonymous_Access_Types
1950 (Spec_Id : Entity_Id;
1957 -- Itype references are only needed by gigi, to force elaboration of
1958 -- itypes. In the absence of code generation, they are not needed.
1960 if not Expander_Active then
1964 E := First_Entity (Spec_Id);
1965 while Present (E) loop
1966 if Ekind (E) = E_Anonymous_Access_Type
1967 and then From_Limited_With (E)
1969 IR := Make_Itype_Reference (Sloc (P_Body));
1972 if No (Declarations (P_Body)) then
1973 Set_Declarations (P_Body, New_List (IR));
1975 Prepend (IR, Declarations (P_Body));
1981 end Check_Anonymous_Access_Types;
1983 -------------------------------------------
1984 -- Declare_Inherited_Private_Subprograms --
1985 -------------------------------------------
1987 procedure Declare_Inherited_Private_Subprograms (Id : Entity_Id) is
1989 function Is_Primitive_Of (T : Entity_Id; S : Entity_Id) return Boolean;
1990 -- Check whether an inherited subprogram S is an operation of an
1991 -- untagged derived type T.
1993 ---------------------
1994 -- Is_Primitive_Of --
1995 ---------------------
1997 function Is_Primitive_Of (T : Entity_Id; S : Entity_Id) return Boolean is
2001 -- If the full view is a scalar type, the type is the anonymous base
2002 -- type, but the operation mentions the first subtype, so check the
2003 -- signature against the base type.
2005 if Base_Type (Etype (S)) = Base_Type (T) then
2009 Formal := First_Formal (S);
2010 while Present (Formal) loop
2011 if Base_Type (Etype (Formal)) = Base_Type (T) then
2015 Next_Formal (Formal);
2020 end Is_Primitive_Of;
2027 Op_Elmt_2 : Elmt_Id;
2028 Prim_Op : Entity_Id;
2029 New_Op : Entity_Id := Empty;
2030 Parent_Subp : Entity_Id;
2033 -- Start of processing for Declare_Inherited_Private_Subprograms
2036 E := First_Entity (Id);
2037 while Present (E) loop
2039 -- If the entity is a nonprivate type extension whose parent type
2040 -- is declared in an open scope, then the type may have inherited
2041 -- operations that now need to be made visible. Ditto if the entity
2042 -- is a formal derived type in a child unit.
2044 if ((Is_Derived_Type (E) and then not Is_Private_Type (E))
2046 (Nkind (Parent (E)) = N_Private_Extension_Declaration
2047 and then Is_Generic_Type (E)))
2048 and then In_Open_Scopes (Scope (Etype (E)))
2049 and then Is_Base_Type (E)
2051 if Is_Tagged_Type (E) then
2052 Op_List := Primitive_Operations (E);
2054 Tag := First_Tag_Component (E);
2056 Op_Elmt := First_Elmt (Op_List);
2057 while Present (Op_Elmt) loop
2058 Prim_Op := Node (Op_Elmt);
2060 -- Search primitives that are implicit operations with an
2061 -- internal name whose parent operation has a normal name.
2063 if Present (Alias (Prim_Op))
2064 and then Find_Dispatching_Type (Alias (Prim_Op)) /= E
2065 and then not Comes_From_Source (Prim_Op)
2066 and then Is_Internal_Name (Chars (Prim_Op))
2067 and then not Is_Internal_Name (Chars (Alias (Prim_Op)))
2069 Parent_Subp := Alias (Prim_Op);
2071 -- Case 1: Check if the type has also an explicit
2072 -- overriding for this primitive.
2074 Op_Elmt_2 := Next_Elmt (Op_Elmt);
2075 while Present (Op_Elmt_2) loop
2077 -- Skip entities with attribute Interface_Alias since
2078 -- they are not overriding primitives (these entities
2079 -- link an interface primitive with their covering
2082 if Chars (Node (Op_Elmt_2)) = Chars (Parent_Subp)
2083 and then Type_Conformant (Prim_Op, Node (Op_Elmt_2))
2084 and then No (Interface_Alias (Node (Op_Elmt_2)))
2086 -- The private inherited operation has been
2087 -- overridden by an explicit subprogram:
2088 -- replace the former by the latter.
2090 New_Op := Node (Op_Elmt_2);
2091 Replace_Elmt (Op_Elmt, New_Op);
2092 Remove_Elmt (Op_List, Op_Elmt_2);
2093 Set_Overridden_Operation (New_Op, Parent_Subp);
2095 -- We don't need to inherit its dispatching slot.
2096 -- Set_All_DT_Position has previously ensured that
2097 -- the same slot was assigned to the two primitives
2100 and then Present (DTC_Entity (New_Op))
2101 and then Present (DTC_Entity (Prim_Op))
2104 (DT_Position (New_Op) = DT_Position (Prim_Op));
2108 goto Next_Primitive;
2111 Next_Elmt (Op_Elmt_2);
2114 -- Case 2: We have not found any explicit overriding and
2115 -- hence we need to declare the operation (i.e., make it
2118 Derive_Subprogram (New_Op, Alias (Prim_Op), E, Etype (E));
2120 -- Inherit the dispatching slot if E is already frozen
2123 and then Present (DTC_Entity (Alias (Prim_Op)))
2125 Set_DTC_Entity_Value (E, New_Op);
2126 Set_DT_Position_Value (New_Op,
2127 DT_Position (Alias (Prim_Op)));
2131 (Is_Dispatching_Operation (New_Op)
2132 and then Node (Last_Elmt (Op_List)) = New_Op);
2134 -- Substitute the new operation for the old one in the
2135 -- type's primitive operations list. Since the new
2136 -- operation was also just added to the end of list,
2137 -- the last element must be removed.
2139 -- (Question: is there a simpler way of declaring the
2140 -- operation, say by just replacing the name of the
2141 -- earlier operation, reentering it in the in the symbol
2142 -- table (how?), and marking it as private???)
2144 Replace_Elmt (Op_Elmt, New_Op);
2145 Remove_Last_Elmt (Op_List);
2149 Next_Elmt (Op_Elmt);
2152 -- Generate listing showing the contents of the dispatch table
2154 if Debug_Flag_ZZ then
2159 -- For untagged type, scan forward to locate inherited hidden
2162 Prim_Op := Next_Entity (E);
2163 while Present (Prim_Op) loop
2164 if Is_Subprogram (Prim_Op)
2165 and then Present (Alias (Prim_Op))
2166 and then not Comes_From_Source (Prim_Op)
2167 and then Is_Internal_Name (Chars (Prim_Op))
2168 and then not Is_Internal_Name (Chars (Alias (Prim_Op)))
2169 and then Is_Primitive_Of (E, Prim_Op)
2171 Derive_Subprogram (New_Op, Alias (Prim_Op), E, Etype (E));
2174 Next_Entity (Prim_Op);
2176 -- Derived operations appear immediately after the type
2177 -- declaration (or the following subtype indication for
2178 -- a derived scalar type). Further declarations cannot
2179 -- include inherited operations of the type.
2181 if Present (Prim_Op) then
2182 exit when Ekind (Prim_Op) not in Overloadable_Kind;
2190 end Declare_Inherited_Private_Subprograms;
2192 -----------------------
2193 -- End_Package_Scope --
2194 -----------------------
2196 procedure End_Package_Scope (P : Entity_Id) is
2198 Uninstall_Declarations (P);
2200 end End_Package_Scope;
2202 ---------------------------
2203 -- Exchange_Declarations --
2204 ---------------------------
2206 procedure Exchange_Declarations (Id : Entity_Id) is
2207 Full_Id : constant Entity_Id := Full_View (Id);
2208 H1 : constant Entity_Id := Homonym (Id);
2209 Next1 : constant Entity_Id := Next_Entity (Id);
2214 -- If missing full declaration for type, nothing to exchange
2216 if No (Full_Id) then
2220 -- Otherwise complete the exchange, and preserve semantic links
2222 Next2 := Next_Entity (Full_Id);
2223 H2 := Homonym (Full_Id);
2225 -- Reset full declaration pointer to reflect the switched entities and
2226 -- readjust the next entity chains.
2228 Exchange_Entities (Id, Full_Id);
2230 Link_Entities (Id, Next1);
2231 Set_Homonym (Id, H1);
2233 Set_Full_View (Full_Id, Id);
2234 Link_Entities (Full_Id, Next2);
2235 Set_Homonym (Full_Id, H2);
2236 end Exchange_Declarations;
2238 ----------------------------
2239 -- Install_Package_Entity --
2240 ----------------------------
2242 procedure Install_Package_Entity (Id : Entity_Id) is
2244 if not Is_Internal (Id) then
2245 if Debug_Flag_E then
2246 Write_Str ("Install: ");
2247 Write_Name (Chars (Id));
2251 if Is_Child_Unit (Id) then
2254 -- Do not enter implicitly inherited non-overridden subprograms of
2255 -- a tagged type back into visibility if they have non-conformant
2256 -- homographs (Ada RM 8.3 12.3/2).
2258 elsif Is_Hidden_Non_Overridden_Subpgm (Id) then
2262 Set_Is_Immediately_Visible (Id);
2265 end Install_Package_Entity;
2267 ----------------------------------
2268 -- Install_Private_Declarations --
2269 ----------------------------------
2271 procedure Install_Private_Declarations (P : Entity_Id) is
2274 Priv_Deps : Elist_Id;
2276 procedure Swap_Private_Dependents (Priv_Deps : Elist_Id);
2277 -- When the full view of a private type is made available, we do the
2278 -- same for its private dependents under proper visibility conditions.
2279 -- When compiling a child unit this needs to be done recursively.
2281 -----------------------------
2282 -- Swap_Private_Dependents --
2283 -----------------------------
2285 procedure Swap_Private_Dependents (Priv_Deps : Elist_Id) is
2289 Priv_Elmt : Elmt_Id;
2293 Priv_Elmt := First_Elmt (Priv_Deps);
2294 while Present (Priv_Elmt) loop
2295 Priv := Node (Priv_Elmt);
2297 -- Before the exchange, verify that the presence of the Full_View
2298 -- field. This field will be empty if the entity has already been
2299 -- installed due to a previous call.
2301 if Present (Full_View (Priv)) and then Is_Visible_Dependent (Priv)
2303 if Is_Private_Type (Priv) then
2304 Cunit := Cunit_Entity (Current_Sem_Unit);
2305 Deps := Private_Dependents (Priv);
2311 -- For each subtype that is swapped, we also swap the reference
2312 -- to it in Private_Dependents, to allow access to it when we
2313 -- swap them out in End_Package_Scope.
2315 Replace_Elmt (Priv_Elmt, Full_View (Priv));
2317 -- Ensure that both views of the dependent private subtype are
2318 -- immediately visible if within some open scope. Check full
2319 -- view before exchanging views.
2321 if In_Open_Scopes (Scope (Full_View (Priv))) then
2322 Set_Is_Immediately_Visible (Priv);
2325 Exchange_Declarations (Priv);
2326 Set_Is_Immediately_Visible
2327 (Priv, In_Open_Scopes (Scope (Priv)));
2329 Set_Is_Potentially_Use_Visible
2330 (Priv, Is_Potentially_Use_Visible (Node (Priv_Elmt)));
2332 -- Recurse for child units, except in generic child units,
2333 -- which unfortunately handle private_dependents separately.
2334 -- Note that the current unit may not have been analyzed,
2335 -- for example a package body, so we cannot rely solely on
2336 -- the Is_Child_Unit flag, but that's only an optimization.
2339 and then (No (Etype (Cunit)) or else Is_Child_Unit (Cunit))
2340 and then not Is_Empty_Elmt_List (Deps)
2341 and then not Inside_A_Generic
2343 Swap_Private_Dependents (Deps);
2347 Next_Elmt (Priv_Elmt);
2349 end Swap_Private_Dependents;
2351 -- Start of processing for Install_Private_Declarations
2354 -- First exchange declarations for private types, so that the full
2355 -- declaration is visible. For each private type, we check its
2356 -- Private_Dependents list and also exchange any subtypes of or derived
2357 -- types from it. Finally, if this is a Taft amendment type, the
2358 -- incomplete declaration is irrelevant, and we want to link the
2359 -- eventual full declaration with the original private one so we
2360 -- also skip the exchange.
2362 Id := First_Entity (P);
2363 while Present (Id) and then Id /= First_Private_Entity (P) loop
2364 if Is_Private_Base_Type (Id)
2365 and then Present (Full_View (Id))
2366 and then Comes_From_Source (Full_View (Id))
2367 and then Scope (Full_View (Id)) = Scope (Id)
2368 and then Ekind (Full_View (Id)) /= E_Incomplete_Type
2370 -- If there is a use-type clause on the private type, set the full
2371 -- view accordingly.
2373 Set_In_Use (Full_View (Id), In_Use (Id));
2374 Full := Full_View (Id);
2376 if Is_Private_Base_Type (Full)
2377 and then Has_Private_Declaration (Full)
2378 and then Nkind (Parent (Full)) = N_Full_Type_Declaration
2379 and then In_Open_Scopes (Scope (Etype (Full)))
2380 and then In_Package_Body (Current_Scope)
2381 and then not Is_Private_Type (Etype (Full))
2383 -- This is the completion of a private type by a derivation
2384 -- from another private type which is not private anymore. This
2385 -- can only happen in a package nested within a child package,
2386 -- when the parent type is defined in the parent unit. At this
2387 -- point the current type is not private either, and we have
2388 -- to install the underlying full view, which is now visible.
2389 -- Save the current full view as well, so that all views can be
2390 -- restored on exit. It may seem that after compiling the child
2391 -- body there are not environments to restore, but the back-end
2392 -- expects those links to be valid, and freeze nodes depend on
2395 if No (Full_View (Full))
2396 and then Present (Underlying_Full_View (Full))
2398 Set_Full_View (Id, Underlying_Full_View (Full));
2399 Set_Underlying_Full_View (Id, Full);
2400 Set_Is_Underlying_Full_View (Full);
2402 Set_Underlying_Full_View (Full, Empty);
2403 Set_Is_Frozen (Full_View (Id));
2407 Priv_Deps := Private_Dependents (Id);
2408 Exchange_Declarations (Id);
2409 Set_Is_Immediately_Visible (Id);
2410 Swap_Private_Dependents (Priv_Deps);
2416 -- Next make other declarations in the private part visible as well
2418 Id := First_Private_Entity (P);
2419 while Present (Id) loop
2420 Install_Package_Entity (Id);
2421 Set_Is_Hidden (Id, False);
2425 -- An abstract state is partially refined when it has at least one
2426 -- Part_Of constituent. Since these constituents are being installed
2427 -- into visibility, update the partial refinement status of any state
2428 -- defined in the associated package, subject to at least one Part_Of
2431 if Ekind_In (P, E_Generic_Package, E_Package) then
2433 States : constant Elist_Id := Abstract_States (P);
2434 State_Elmt : Elmt_Id;
2435 State_Id : Entity_Id;
2438 if Present (States) then
2439 State_Elmt := First_Elmt (States);
2440 while Present (State_Elmt) loop
2441 State_Id := Node (State_Elmt);
2443 if Present (Part_Of_Constituents (State_Id)) then
2444 Set_Has_Partial_Visible_Refinement (State_Id);
2447 Next_Elmt (State_Elmt);
2453 -- Indicate that the private part is currently visible, so it can be
2454 -- properly reset on exit.
2456 Set_In_Private_Part (P);
2457 end Install_Private_Declarations;
2459 ----------------------------------
2460 -- Install_Visible_Declarations --
2461 ----------------------------------
2463 procedure Install_Visible_Declarations (P : Entity_Id) is
2465 Last_Entity : Entity_Id;
2469 (Is_Package_Or_Generic_Package (P) or else Is_Record_Type (P));
2471 if Is_Package_Or_Generic_Package (P) then
2472 Last_Entity := First_Private_Entity (P);
2474 Last_Entity := Empty;
2477 Id := First_Entity (P);
2478 while Present (Id) and then Id /= Last_Entity loop
2479 Install_Package_Entity (Id);
2482 end Install_Visible_Declarations;
2484 --------------------------
2485 -- Is_Private_Base_Type --
2486 --------------------------
2488 function Is_Private_Base_Type (E : Entity_Id) return Boolean is
2490 return Ekind (E) = E_Private_Type
2491 or else Ekind (E) = E_Limited_Private_Type
2492 or else Ekind (E) = E_Record_Type_With_Private;
2493 end Is_Private_Base_Type;
2495 --------------------------
2496 -- Is_Visible_Dependent --
2497 --------------------------
2499 function Is_Visible_Dependent (Dep : Entity_Id) return Boolean
2501 S : constant Entity_Id := Scope (Dep);
2504 -- Renamings created for actual types have the visibility of the actual
2506 if Ekind (S) = E_Package
2507 and then Is_Generic_Instance (S)
2508 and then (Is_Generic_Actual_Type (Dep)
2509 or else Is_Generic_Actual_Type (Full_View (Dep)))
2513 elsif not (Is_Derived_Type (Dep))
2514 and then Is_Derived_Type (Full_View (Dep))
2516 -- When instantiating a package body, the scope stack is empty, so
2517 -- check instead whether the dependent type is defined in the same
2518 -- scope as the instance itself.
2520 return In_Open_Scopes (S)
2521 or else (Is_Generic_Instance (Current_Scope)
2522 and then Scope (Dep) = Scope (Current_Scope));
2526 end Is_Visible_Dependent;
2528 ----------------------------
2529 -- May_Need_Implicit_Body --
2530 ----------------------------
2532 procedure May_Need_Implicit_Body (E : Entity_Id) is
2533 P : constant Node_Id := Unit_Declaration_Node (E);
2534 S : constant Node_Id := Parent (P);
2539 if not Has_Completion (E)
2540 and then Nkind (P) = N_Package_Declaration
2541 and then (Present (Activation_Chain_Entity (P)) or else Has_RACW (E))
2544 Make_Package_Body (Sloc (E),
2545 Defining_Unit_Name => Make_Defining_Identifier (Sloc (E),
2546 Chars => Chars (E)),
2547 Declarations => New_List);
2549 if Nkind (S) = N_Package_Specification then
2550 if Present (Private_Declarations (S)) then
2551 Decls := Private_Declarations (S);
2553 Decls := Visible_Declarations (S);
2556 Decls := Declarations (S);
2562 end May_Need_Implicit_Body;
2564 ----------------------
2565 -- New_Private_Type --
2566 ----------------------
2568 procedure New_Private_Type (N : Node_Id; Id : Entity_Id; Def : Node_Id) is
2570 -- For other than Ada 2012, enter the name in the current scope
2572 if Ada_Version < Ada_2012 then
2575 -- Ada 2012 (AI05-0162): Enter the name in the current scope. Note that
2576 -- there may be an incomplete previous view.
2582 Prev := Find_Type_Name (N);
2583 pragma Assert (Prev = Id
2584 or else (Ekind (Prev) = E_Incomplete_Type
2585 and then Present (Full_View (Prev))
2586 and then Full_View (Prev) = Id));
2590 if Limited_Present (Def) then
2591 Set_Ekind (Id, E_Limited_Private_Type);
2593 Set_Ekind (Id, E_Private_Type);
2597 Set_Has_Delayed_Freeze (Id);
2598 Set_Is_First_Subtype (Id);
2599 Init_Size_Align (Id);
2601 Set_Is_Constrained (Id,
2602 No (Discriminant_Specifications (N))
2603 and then not Unknown_Discriminants_Present (N));
2605 -- Set tagged flag before processing discriminants, to catch illegal
2608 Set_Is_Tagged_Type (Id, Tagged_Present (Def));
2610 Set_Discriminant_Constraint (Id, No_Elist);
2611 Set_Stored_Constraint (Id, No_Elist);
2613 if Present (Discriminant_Specifications (N)) then
2615 Process_Discriminants (N);
2618 elsif Unknown_Discriminants_Present (N) then
2619 Set_Has_Unknown_Discriminants (Id);
2622 Set_Private_Dependents (Id, New_Elmt_List);
2624 if Tagged_Present (Def) then
2625 Set_Ekind (Id, E_Record_Type_With_Private);
2626 Set_Direct_Primitive_Operations (Id, New_Elmt_List);
2627 Set_Is_Abstract_Type (Id, Abstract_Present (Def));
2628 Set_Is_Limited_Record (Id, Limited_Present (Def));
2629 Set_Has_Delayed_Freeze (Id, True);
2631 -- Recognize Ada.Real_Time.Timing_Events.Timing_Events here
2633 if Is_RTE (Id, RE_Timing_Event) then
2634 Set_Has_Timing_Event (Id);
2637 -- Create a class-wide type with the same attributes
2639 Make_Class_Wide_Type (Id);
2641 elsif Abstract_Present (Def) then
2642 Error_Msg_N ("only a tagged type can be abstract", N);
2644 end New_Private_Type;
2646 ---------------------------------
2647 -- Requires_Completion_In_Body --
2648 ---------------------------------
2650 function Requires_Completion_In_Body
2652 Pack_Id : Entity_Id;
2653 Do_Abstract_States : Boolean := False) return Boolean
2656 -- Always ignore child units. Child units get added to the entity list
2657 -- of a parent unit, but are not original entities of the parent, and
2658 -- so do not affect whether the parent needs a body.
2660 if Is_Child_Unit (Id) then
2663 -- Ignore formal packages and their renamings
2665 elsif Ekind (Id) = E_Package
2666 and then Nkind (Original_Node (Unit_Declaration_Node (Id))) =
2667 N_Formal_Package_Declaration
2671 -- Otherwise test to see if entity requires a completion. Note that
2672 -- subprogram entities whose declaration does not come from source are
2673 -- ignored here on the basis that we assume the expander will provide an
2674 -- implicit completion at some point.
2676 elsif (Is_Overloadable (Id)
2677 and then not Ekind_In (Id, E_Enumeration_Literal, E_Operator)
2678 and then not Is_Abstract_Subprogram (Id)
2679 and then not Has_Completion (Id)
2680 and then Comes_From_Source (Parent (Id)))
2683 (Ekind (Id) = E_Package
2684 and then Id /= Pack_Id
2685 and then not Has_Completion (Id)
2686 and then Unit_Requires_Body (Id, Do_Abstract_States))
2689 (Ekind (Id) = E_Incomplete_Type
2690 and then No (Full_View (Id))
2691 and then not Is_Generic_Type (Id))
2694 (Ekind_In (Id, E_Task_Type, E_Protected_Type)
2695 and then not Has_Completion (Id))
2698 (Ekind (Id) = E_Generic_Package
2699 and then Id /= Pack_Id
2700 and then not Has_Completion (Id)
2701 and then Unit_Requires_Body (Id, Do_Abstract_States))
2704 (Is_Generic_Subprogram (Id)
2705 and then not Has_Completion (Id))
2709 -- Otherwise the entity does not require completion in a package body
2714 end Requires_Completion_In_Body;
2716 ----------------------------
2717 -- Uninstall_Declarations --
2718 ----------------------------
2720 procedure Uninstall_Declarations (P : Entity_Id) is
2721 Decl : constant Node_Id := Unit_Declaration_Node (P);
2725 procedure Preserve_Full_Attributes (Priv : Entity_Id; Full : Entity_Id);
2726 -- Copy to the private declaration the attributes of the full view that
2727 -- need to be available for the partial view also.
2729 procedure Swap_Private_Dependents (Priv_Deps : Elist_Id);
2730 -- When the full view of a private type is made unavailable, we do the
2731 -- same for its private dependents under proper visibility conditions.
2732 -- When compiling a child unit this needs to be done recursively.
2734 function Type_In_Use (T : Entity_Id) return Boolean;
2735 -- Check whether type or base type appear in an active use_type clause
2737 ------------------------------
2738 -- Preserve_Full_Attributes --
2739 ------------------------------
2741 procedure Preserve_Full_Attributes
2745 Full_Base : constant Entity_Id := Base_Type (Full);
2746 Priv_Is_Base_Type : constant Boolean := Is_Base_Type (Priv);
2749 Set_Size_Info (Priv, Full);
2750 Set_RM_Size (Priv, RM_Size (Full));
2751 Set_Size_Known_At_Compile_Time
2752 (Priv, Size_Known_At_Compile_Time (Full));
2753 Set_Is_Volatile (Priv, Is_Volatile (Full));
2754 Set_Treat_As_Volatile (Priv, Treat_As_Volatile (Full));
2755 Set_Is_Ada_2005_Only (Priv, Is_Ada_2005_Only (Full));
2756 Set_Is_Ada_2012_Only (Priv, Is_Ada_2012_Only (Full));
2757 Set_Has_Pragma_Unmodified (Priv, Has_Pragma_Unmodified (Full));
2758 Set_Has_Pragma_Unreferenced (Priv, Has_Pragma_Unreferenced (Full));
2759 Set_Has_Pragma_Unreferenced_Objects
2760 (Priv, Has_Pragma_Unreferenced_Objects
2762 if Is_Unchecked_Union (Full) then
2763 Set_Is_Unchecked_Union (Base_Type (Priv));
2765 -- Why is atomic not copied here ???
2767 if Referenced (Full) then
2768 Set_Referenced (Priv);
2771 if Priv_Is_Base_Type then
2772 Set_Is_Controlled_Active
2773 (Priv, Is_Controlled_Active (Full_Base));
2774 Set_Finalize_Storage_Only
2775 (Priv, Finalize_Storage_Only (Full_Base));
2776 Set_Has_Controlled_Component
2777 (Priv, Has_Controlled_Component (Full_Base));
2779 Propagate_Concurrent_Flags (Priv, Base_Type (Full));
2782 -- As explained in Freeze_Entity, private types are required to point
2783 -- to the same freeze node as their corresponding full view, if any.
2784 -- But we ought not to overwrite a node already inserted in the tree.
2787 (Serious_Errors_Detected /= 0
2788 or else No (Freeze_Node (Priv))
2789 or else No (Parent (Freeze_Node (Priv)))
2790 or else Freeze_Node (Priv) = Freeze_Node (Full));
2792 Set_Freeze_Node (Priv, Freeze_Node (Full));
2794 -- Propagate Default_Initial_Condition-related attributes from the
2795 -- base type of the full view to the full view and vice versa. This
2796 -- may seem strange, but is necessary depending on which type
2797 -- triggered the generation of the DIC procedure body. As a result,
2798 -- both the full view and its base type carry the same DIC-related
2801 Propagate_DIC_Attributes (Full, From_Typ => Full_Base);
2802 Propagate_DIC_Attributes (Full_Base, From_Typ => Full);
2804 -- Propagate Default_Initial_Condition-related attributes from the
2805 -- full view to the private view.
2807 Propagate_DIC_Attributes (Priv, From_Typ => Full);
2809 -- Propagate invariant-related attributes from the base type of the
2810 -- full view to the full view and vice versa. This may seem strange,
2811 -- but is necessary depending on which type triggered the generation
2812 -- of the invariant procedure body. As a result, both the full view
2813 -- and its base type carry the same invariant-related information.
2815 Propagate_Invariant_Attributes (Full, From_Typ => Full_Base);
2816 Propagate_Invariant_Attributes (Full_Base, From_Typ => Full);
2818 -- Propagate invariant-related attributes from the full view to the
2821 Propagate_Invariant_Attributes (Priv, From_Typ => Full);
2823 if Is_Tagged_Type (Priv)
2824 and then Is_Tagged_Type (Full)
2825 and then not Error_Posted (Full)
2827 if Is_Tagged_Type (Priv) then
2829 -- If the type is tagged, the tag itself must be available on
2830 -- the partial view, for expansion purposes.
2832 Set_First_Entity (Priv, First_Entity (Full));
2834 -- If there are discriminants in the partial view, these remain
2835 -- visible. Otherwise only the tag itself is visible, and there
2836 -- are no nameable components in the partial view.
2838 if No (Last_Entity (Priv)) then
2839 Set_Last_Entity (Priv, First_Entity (Priv));
2843 Set_Has_Discriminants (Priv, Has_Discriminants (Full));
2845 if Has_Discriminants (Full) then
2846 Set_Discriminant_Constraint (Priv,
2847 Discriminant_Constraint (Full));
2850 end Preserve_Full_Attributes;
2852 -----------------------------
2853 -- Swap_Private_Dependents --
2854 -----------------------------
2856 procedure Swap_Private_Dependents (Priv_Deps : Elist_Id) is
2860 Priv_Elmt : Elmt_Id;
2864 Priv_Elmt := First_Elmt (Priv_Deps);
2865 while Present (Priv_Elmt) loop
2866 Priv := Node (Priv_Elmt);
2868 -- Before we do the swap, we verify the presence of the Full_View
2869 -- field, which may be empty due to a swap by a previous call to
2870 -- End_Package_Scope (e.g. from the freezing mechanism).
2872 if Present (Full_View (Priv)) then
2873 if Is_Private_Type (Priv) then
2874 Cunit := Cunit_Entity (Current_Sem_Unit);
2875 Deps := Private_Dependents (Priv);
2882 or else not In_Open_Scopes (Scope (Priv))
2884 Set_Is_Immediately_Visible (Priv, False);
2887 if Is_Visible_Dependent (Priv) then
2888 Preserve_Full_Attributes (Priv, Full_View (Priv));
2889 Replace_Elmt (Priv_Elmt, Full_View (Priv));
2890 Exchange_Declarations (Priv);
2892 -- Recurse for child units, except in generic child units,
2893 -- which unfortunately handle private_dependents separately.
2894 -- Note that the current unit may not have been analyzed,
2895 -- for example a package body, so we cannot rely solely on
2896 -- the Is_Child_Unit flag, but that's only an optimization.
2899 and then (No (Etype (Cunit)) or else Is_Child_Unit (Cunit))
2900 and then not Is_Empty_Elmt_List (Deps)
2901 and then not Inside_A_Generic
2903 Swap_Private_Dependents (Deps);
2908 Next_Elmt (Priv_Elmt);
2910 end Swap_Private_Dependents;
2916 function Type_In_Use (T : Entity_Id) return Boolean is
2918 return Scope (Base_Type (T)) = P
2919 and then (In_Use (T) or else In_Use (Base_Type (T)));
2922 -- Start of processing for Uninstall_Declarations
2925 Id := First_Entity (P);
2926 while Present (Id) and then Id /= First_Private_Entity (P) loop
2927 if Debug_Flag_E then
2928 Write_Str ("unlinking visible entity ");
2929 Write_Int (Int (Id));
2933 -- On exit from the package scope, we must preserve the visibility
2934 -- established by use clauses in the current scope. Two cases:
2936 -- a) If the entity is an operator, it may be a primitive operator of
2937 -- a type for which there is a visible use-type clause.
2939 -- b) For other entities, their use-visibility is determined by a
2940 -- visible use clause for the package itself or a use-all-type clause
2941 -- applied directly to the entity's type. For a generic instance,
2942 -- the instantiation of the formals appears in the visible part,
2943 -- but the formals are private and remain so.
2945 if Ekind (Id) = E_Function
2946 and then Is_Operator_Symbol_Name (Chars (Id))
2947 and then not Is_Hidden (Id)
2948 and then not Error_Posted (Id)
2950 Set_Is_Potentially_Use_Visible (Id,
2952 or else Type_In_Use (Etype (Id))
2953 or else Type_In_Use (Etype (First_Formal (Id)))
2954 or else (Present (Next_Formal (First_Formal (Id)))
2957 (Etype (Next_Formal (First_Formal (Id))))));
2959 if In_Use (P) and then not Is_Hidden (Id) then
2961 -- A child unit of a use-visible package remains use-visible
2962 -- only if it is itself a visible child unit. Otherwise it
2963 -- would remain visible in other contexts where P is use-
2964 -- visible, because once compiled it stays in the entity list
2965 -- of its parent unit.
2967 if Is_Child_Unit (Id) then
2968 Set_Is_Potentially_Use_Visible
2969 (Id, Is_Visible_Lib_Unit (Id));
2971 Set_Is_Potentially_Use_Visible (Id);
2974 -- We need to avoid incorrectly marking enumeration literals as
2975 -- non-visible when a visible use-all-type clause is in effect.
2977 elsif Type_In_Use (Etype (Id))
2978 and then Nkind (Current_Use_Clause (Etype (Id))) =
2980 and then All_Present (Current_Use_Clause (Etype (Id)))
2985 Set_Is_Potentially_Use_Visible (Id, False);
2989 -- Local entities are not immediately visible outside of the package
2991 Set_Is_Immediately_Visible (Id, False);
2993 -- If this is a private type with a full view (for example a local
2994 -- subtype of a private type declared elsewhere), ensure that the
2995 -- full view is also removed from visibility: it may be exposed when
2996 -- swapping views in an instantiation. Similarly, ensure that the
2997 -- use-visibility is properly set on both views.
2999 if Is_Type (Id) and then Present (Full_View (Id)) then
3000 Set_Is_Immediately_Visible (Full_View (Id), False);
3001 Set_Is_Potentially_Use_Visible (Full_View (Id),
3002 Is_Potentially_Use_Visible (Id));
3005 if Is_Tagged_Type (Id) and then Ekind (Id) = E_Record_Type then
3006 Check_Abstract_Overriding (Id);
3007 Check_Conventions (Id);
3010 if Ekind_In (Id, E_Private_Type, E_Limited_Private_Type)
3011 and then No (Full_View (Id))
3012 and then not Is_Generic_Type (Id)
3013 and then not Is_Derived_Type (Id)
3015 Error_Msg_N ("missing full declaration for private type&", Id);
3017 elsif Ekind (Id) = E_Record_Type_With_Private
3018 and then not Is_Generic_Type (Id)
3019 and then No (Full_View (Id))
3021 if Nkind (Parent (Id)) = N_Private_Type_Declaration then
3022 Error_Msg_N ("missing full declaration for private type&", Id);
3025 ("missing full declaration for private extension", Id);
3028 -- Case of constant, check for deferred constant declaration with
3029 -- no full view. Likely just a matter of a missing expression, or
3030 -- accidental use of the keyword constant.
3032 elsif Ekind (Id) = E_Constant
3034 -- OK if constant value present
3036 and then No (Constant_Value (Id))
3038 -- OK if full view present
3040 and then No (Full_View (Id))
3042 -- OK if imported, since that provides the completion
3044 and then not Is_Imported (Id)
3046 -- OK if object declaration replaced by renaming declaration as
3047 -- a result of OK_To_Rename processing (e.g. for concatenation)
3049 and then Nkind (Parent (Id)) /= N_Object_Renaming_Declaration
3051 -- OK if object declaration with the No_Initialization flag set
3053 and then not (Nkind (Parent (Id)) = N_Object_Declaration
3054 and then No_Initialization (Parent (Id)))
3056 -- If no private declaration is present, we assume the user did
3057 -- not intend a deferred constant declaration and the problem
3058 -- is simply that the initializing expression is missing.
3060 if not Has_Private_Declaration (Etype (Id)) then
3062 -- We assume that the user did not intend a deferred constant
3063 -- declaration, and the expression is just missing.
3066 ("constant declaration requires initialization expression",
3069 if Is_Limited_Type (Etype (Id)) then
3071 ("\if variable intended, remove CONSTANT from declaration",
3075 -- Otherwise if a private declaration is present, then we are
3076 -- missing the full declaration for the deferred constant.
3080 ("missing full declaration for deferred constant (RM 7.4)",
3083 if Is_Limited_Type (Etype (Id)) then
3085 ("\if variable intended, remove CONSTANT from declaration",
3094 -- If the specification was installed as the parent of a public child
3095 -- unit, the private declarations were not installed, and there is
3098 if not In_Private_Part (P) then
3101 Set_In_Private_Part (P, False);
3104 -- Make private entities invisible and exchange full and private
3105 -- declarations for private types. Id is now the first private entity
3108 while Present (Id) loop
3109 if Debug_Flag_E then
3110 Write_Str ("unlinking private entity ");
3111 Write_Int (Int (Id));
3115 if Is_Tagged_Type (Id) and then Ekind (Id) = E_Record_Type then
3116 Check_Abstract_Overriding (Id);
3117 Check_Conventions (Id);
3120 Set_Is_Immediately_Visible (Id, False);
3122 if Is_Private_Base_Type (Id) and then Present (Full_View (Id)) then
3123 Full := Full_View (Id);
3125 -- If the partial view is not declared in the visible part of the
3126 -- package (as is the case when it is a type derived from some
3127 -- other private type in the private part of the current package),
3128 -- no exchange takes place.
3131 or else List_Containing (Parent (Id)) /=
3132 Visible_Declarations (Specification (Decl))
3137 -- The entry in the private part points to the full declaration,
3138 -- which is currently visible. Exchange them so only the private
3139 -- type declaration remains accessible, and link private and full
3140 -- declaration in the opposite direction. Before the actual
3141 -- exchange, we copy back attributes of the full view that must
3142 -- be available to the partial view too.
3144 Preserve_Full_Attributes (Id, Full);
3146 Set_Is_Potentially_Use_Visible (Id, In_Use (P));
3148 -- The following test may be redundant, as this is already
3149 -- diagnosed in sem_ch3. ???
3151 if not Is_Definite_Subtype (Full)
3152 and then Is_Definite_Subtype (Id)
3154 Error_Msg_Sloc := Sloc (Parent (Id));
3156 ("full view of& not compatible with declaration#", Full, Id);
3159 -- Swap out the subtypes and derived types of Id that
3160 -- were compiled in this scope, or installed previously
3161 -- by Install_Private_Declarations.
3163 Swap_Private_Dependents (Private_Dependents (Id));
3165 -- Now restore the type itself to its private view
3167 Exchange_Declarations (Id);
3169 -- If we have installed an underlying full view for a type derived
3170 -- from a private type in a child unit, restore the proper views
3171 -- of private and full view. See corresponding code in
3172 -- Install_Private_Declarations.
3174 -- After the exchange, Full denotes the private type in the
3175 -- visible part of the package.
3177 if Is_Private_Base_Type (Full)
3178 and then Present (Full_View (Full))
3179 and then Present (Underlying_Full_View (Full))
3180 and then In_Package_Body (Current_Scope)
3182 Set_Full_View (Full, Underlying_Full_View (Full));
3183 Set_Underlying_Full_View (Full, Empty);
3186 elsif Ekind (Id) = E_Incomplete_Type
3187 and then Comes_From_Source (Id)
3188 and then No (Full_View (Id))
3190 -- Mark Taft amendment types. Verify that there are no primitive
3191 -- operations declared for the type (3.10.1(9)).
3193 Set_Has_Completion_In_Body (Id);
3200 Elmt := First_Elmt (Private_Dependents (Id));
3201 while Present (Elmt) loop
3202 Subp := Node (Elmt);
3204 -- Is_Primitive is tested because there can be cases where
3205 -- nonprimitive subprograms (in nested packages) are added
3206 -- to the Private_Dependents list.
3208 if Is_Overloadable (Subp) and then Is_Primitive (Subp) then
3210 ("type& must be completed in the private part",
3213 -- The result type of an access-to-function type cannot be a
3214 -- Taft-amendment type, unless the version is Ada 2012 or
3215 -- later (see AI05-151).
3217 elsif Ada_Version < Ada_2012
3218 and then Ekind (Subp) = E_Subprogram_Type
3220 if Etype (Subp) = Id
3222 (Is_Class_Wide_Type (Etype (Subp))
3223 and then Etype (Etype (Subp)) = Id)
3226 ("type& must be completed in the private part",
3227 Associated_Node_For_Itype (Subp), Id);
3235 elsif not Is_Child_Unit (Id)
3236 and then (not Is_Private_Type (Id) or else No (Full_View (Id)))
3239 Set_Is_Potentially_Use_Visible (Id, False);
3245 end Uninstall_Declarations;
3247 ------------------------
3248 -- Unit_Requires_Body --
3249 ------------------------
3251 function Unit_Requires_Body
3252 (Pack_Id : Entity_Id;
3253 Do_Abstract_States : Boolean := False) return Boolean
3257 Requires_Body : Boolean := False;
3258 -- Flag set when the unit has at least one construct that requires
3259 -- completion in a body.
3262 -- Imported entity never requires body. Right now, only subprograms can
3263 -- be imported, but perhaps in the future we will allow import of
3266 if Is_Imported (Pack_Id) then
3269 -- Body required if library package with pragma Elaborate_Body
3271 elsif Has_Pragma_Elaborate_Body (Pack_Id) then
3274 -- Body required if subprogram
3276 elsif Is_Subprogram_Or_Generic_Subprogram (Pack_Id) then
3279 -- Treat a block as requiring a body
3281 elsif Ekind (Pack_Id) = E_Block then
3284 elsif Ekind (Pack_Id) = E_Package
3285 and then Nkind (Parent (Pack_Id)) = N_Package_Specification
3286 and then Present (Generic_Parent (Parent (Pack_Id)))
3289 G_P : constant Entity_Id := Generic_Parent (Parent (Pack_Id));
3291 if Has_Pragma_Elaborate_Body (G_P) then
3297 -- Traverse the entity chain of the package and look for constructs that
3298 -- require a completion in a body.
3300 E := First_Entity (Pack_Id);
3301 while Present (E) loop
3303 -- Skip abstract states because their completion depends on several
3304 -- criteria (see below).
3306 if Ekind (E) = E_Abstract_State then
3309 elsif Requires_Completion_In_Body
3310 (E, Pack_Id, Do_Abstract_States)
3312 Requires_Body := True;
3319 -- A [generic] package that defines at least one non-null abstract state
3320 -- requires a completion only when at least one other construct requires
3321 -- a completion in a body (SPARK RM 7.1.4(4) and (5)). This check is not
3322 -- performed if the caller requests this behavior.
3324 if Do_Abstract_States
3325 and then Ekind_In (Pack_Id, E_Generic_Package, E_Package)
3326 and then Has_Non_Null_Abstract_State (Pack_Id)
3327 and then Requires_Body
3332 return Requires_Body;
3333 end Unit_Requires_Body;
3335 -----------------------------
3336 -- Unit_Requires_Body_Info --
3337 -----------------------------
3339 procedure Unit_Requires_Body_Info (Pack_Id : Entity_Id) is
3343 -- An imported entity never requires body. Right now, only subprograms
3344 -- can be imported, but perhaps in the future we will allow import of
3347 if Is_Imported (Pack_Id) then
3350 -- Body required if library package with pragma Elaborate_Body
3352 elsif Has_Pragma_Elaborate_Body (Pack_Id) then
3353 Error_Msg_N ("info: & requires body (Elaborate_Body)?Y?", Pack_Id);
3355 -- Body required if subprogram
3357 elsif Is_Subprogram_Or_Generic_Subprogram (Pack_Id) then
3358 Error_Msg_N ("info: & requires body (subprogram case)?Y?", Pack_Id);
3360 -- Body required if generic parent has Elaborate_Body
3362 elsif Ekind (Pack_Id) = E_Package
3363 and then Nkind (Parent (Pack_Id)) = N_Package_Specification
3364 and then Present (Generic_Parent (Parent (Pack_Id)))
3367 G_P : constant Entity_Id := Generic_Parent (Parent (Pack_Id));
3369 if Has_Pragma_Elaborate_Body (G_P) then
3371 ("info: & requires body (generic parent Elaborate_Body)?Y?",
3376 -- A [generic] package that introduces at least one non-null abstract
3377 -- state requires completion. However, there is a separate rule that
3378 -- requires that such a package have a reason other than this for a
3379 -- body being required (if necessary a pragma Elaborate_Body must be
3380 -- provided). If Ignore_Abstract_State is True, we don't do this check
3381 -- (so we can use Unit_Requires_Body to check for some other reason).
3383 elsif Ekind_In (Pack_Id, E_Generic_Package, E_Package)
3384 and then Present (Abstract_States (Pack_Id))
3385 and then not Is_Null_State
3386 (Node (First_Elmt (Abstract_States (Pack_Id))))
3389 ("info: & requires body (non-null abstract state aspect)?Y?",
3393 -- Otherwise search entity chain for entity requiring completion
3395 E := First_Entity (Pack_Id);
3396 while Present (E) loop
3397 if Requires_Completion_In_Body (E, Pack_Id) then
3398 Error_Msg_Node_2 := E;
3400 ("info: & requires body (& requires completion)?Y?", E, Pack_Id);
3405 end Unit_Requires_Body_Info;