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.
929 if Ekind (Scope (Spec_Id)) = E_Package
930 and then Scope (Spec_Id) /= Standard_Standard
932 Declare_Inherited_Private_Subprograms (Spec_Id);
935 if Present (Declarations (N)) then
936 Analyze_Declarations (Declarations (N));
937 Inspect_Deferred_Constant_Completion (Declarations (N));
940 -- Verify that the SPARK_Mode of the body agrees with that of its spec
942 if Present (SPARK_Pragma (Body_Id)) then
943 if Present (SPARK_Aux_Pragma (Spec_Id)) then
944 if Get_SPARK_Mode_From_Annotation (SPARK_Aux_Pragma (Spec_Id)) =
947 Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Body_Id)) = On
949 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
950 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
951 Error_Msg_Sloc := Sloc (SPARK_Aux_Pragma (Spec_Id));
953 ("\value Off was set for SPARK_Mode on & #", N, Spec_Id);
957 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
958 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
959 Error_Msg_Sloc := Sloc (Spec_Id);
961 ("\no value was set for SPARK_Mode on & #", N, Spec_Id);
965 -- Analyze_Declarations has caused freezing of all types. Now generate
966 -- bodies for RACW primitives and stream attributes, if any.
968 if Ekind (Spec_Id) = E_Package and then Has_RACW (Spec_Id) then
970 -- Attach subprogram bodies to support RACWs declared in spec
972 Append_RACW_Bodies (Declarations (N), Spec_Id);
973 Analyze_List (Declarations (N));
976 HSS := Handled_Statement_Sequence (N);
978 if Present (HSS) then
979 Process_End_Label (HSS, 't', Spec_Id);
982 -- Check that elaboration code in a preelaborable package body is
983 -- empty other than null statements and labels (RM 10.2.1(6)).
985 Validate_Null_Statement_Sequence (N);
988 Validate_Categorization_Dependency (N, Spec_Id);
989 Check_Completion (Body_Id);
991 -- Generate start of body reference. Note that we do this fairly late,
992 -- because the call will use In_Extended_Main_Source_Unit as a check,
993 -- and we want to make sure that Corresponding_Stub links are set
995 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
997 -- For a generic package, collect global references and mark them on
998 -- the original body so that they are not resolved again at the point
1001 if Ekind (Spec_Id) /= E_Package then
1002 Save_Global_References (Original_Node (N));
1006 -- The entities of the package body have so far been chained onto the
1007 -- declaration chain for the spec. That's been fine while we were in the
1008 -- body, since we wanted them to be visible, but now that we are leaving
1009 -- the package body, they are no longer visible, so we remove them from
1010 -- the entity chain of the package spec entity, and copy them to the
1011 -- entity chain of the package body entity, where they will never again
1014 if Present (Last_Spec_Entity) then
1015 Set_First_Entity (Body_Id, Next_Entity (Last_Spec_Entity));
1016 Set_Next_Entity (Last_Spec_Entity, Empty);
1017 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
1018 Set_Last_Entity (Spec_Id, Last_Spec_Entity);
1021 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
1022 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
1023 Set_First_Entity (Spec_Id, Empty);
1024 Set_Last_Entity (Spec_Id, Empty);
1027 Update_Use_Clause_Chain;
1028 End_Package_Scope (Spec_Id);
1030 -- All entities declared in body are not visible
1036 E := First_Entity (Body_Id);
1037 while Present (E) loop
1038 Set_Is_Immediately_Visible (E, False);
1039 Set_Is_Potentially_Use_Visible (E, False);
1042 -- Child units may appear on the entity list (e.g. if they appear
1043 -- in the context of a subunit) but they are not body entities.
1045 if not Is_Child_Unit (E) then
1046 Set_Is_Package_Body_Entity (E);
1053 Check_References (Body_Id);
1055 -- For a generic unit, check that the formal parameters are referenced,
1056 -- and that local variables are used, as for regular packages.
1058 if Ekind (Spec_Id) = E_Generic_Package then
1059 Check_References (Spec_Id);
1062 -- At this point all entities of the package body are externally visible
1063 -- to the linker as their Is_Public flag is set to True. This proactive
1064 -- approach is necessary because an inlined or a generic body for which
1065 -- code is generated in other units may need to see these entities. Cut
1066 -- down the number of global symbols that do not need public visibility
1067 -- as this has two beneficial effects:
1068 -- (1) It makes the compilation process more efficient.
1069 -- (2) It gives the code generator more leeway to optimize within each
1070 -- unit, especially subprograms.
1072 -- This is done only for top-level library packages or child units as
1073 -- the algorithm does a top-down traversal of the package body.
1075 if (Scope (Spec_Id) = Standard_Standard or else Is_Child_Unit (Spec_Id))
1076 and then not Is_Generic_Unit (Spec_Id)
1078 Hide_Public_Entities (Declarations (N));
1081 -- If expander is not active, then here is where we turn off the
1082 -- In_Package_Body flag, otherwise it is turned off at the end of the
1083 -- corresponding expansion routine. If this is an instance body, we need
1084 -- to qualify names of local entities, because the body may have been
1085 -- compiled as a preliminary to another instantiation.
1087 if not Expander_Active then
1088 Set_In_Package_Body (Spec_Id, False);
1090 if Is_Generic_Instance (Spec_Id)
1091 and then Operating_Mode = Generate_Code
1093 Qualify_Entity_Names (N);
1097 if Present (Ignored_Ghost_Region) then
1098 Expander_Active := Saved_EA;
1101 Ignore_SPARK_Mode_Pragmas_In_Instance := Saved_ISMP;
1102 Restore_Ghost_Region (Saved_GM, Saved_IGR);
1103 end Analyze_Package_Body_Helper;
1105 ---------------------------------
1106 -- Analyze_Package_Declaration --
1107 ---------------------------------
1109 procedure Analyze_Package_Declaration (N : Node_Id) is
1110 Id : constant Node_Id := Defining_Entity (N);
1112 Is_Comp_Unit : constant Boolean :=
1113 Nkind (Parent (N)) = N_Compilation_Unit;
1115 Body_Required : Boolean;
1116 -- True when this package declaration requires a corresponding body
1119 if Debug_Flag_C then
1120 Write_Str ("==> package spec ");
1121 Write_Name (Chars (Id));
1122 Write_Str (" from ");
1123 Write_Location (Sloc (N));
1128 Generate_Definition (Id);
1130 Set_Ekind (Id, E_Package);
1131 Set_Etype (Id, Standard_Void_Type);
1133 -- Set SPARK_Mode from context
1135 Set_SPARK_Pragma (Id, SPARK_Mode_Pragma);
1136 Set_SPARK_Aux_Pragma (Id, SPARK_Mode_Pragma);
1137 Set_SPARK_Pragma_Inherited (Id);
1138 Set_SPARK_Aux_Pragma_Inherited (Id);
1140 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in case
1141 -- the body of this package is instantiated or inlined later and out of
1142 -- context. The body uses this attribute to restore the value of the
1145 if Ignore_SPARK_Mode_Pragmas_In_Instance then
1146 Set_Ignore_SPARK_Mode_Pragmas (Id);
1149 -- Analyze aspect specifications immediately, since we need to recognize
1150 -- things like Pure early enough to diagnose violations during analysis.
1152 if Has_Aspects (N) then
1153 Analyze_Aspect_Specifications (N, Id);
1156 -- Ada 2005 (AI-217): Check if the package has been illegally named in
1157 -- a limited-with clause of its own context. In this case the error has
1158 -- been previously notified by Analyze_Context.
1160 -- limited with Pkg; -- ERROR
1161 -- package Pkg is ...
1163 if From_Limited_With (Id) then
1169 Set_Is_Pure (Id, Is_Pure (Enclosing_Lib_Unit_Entity));
1170 Set_Categorization_From_Pragmas (N);
1172 Analyze (Specification (N));
1173 Validate_Categorization_Dependency (N, Id);
1175 -- Determine whether the package requires a body. Abstract states are
1176 -- intentionally ignored because they do require refinement which can
1177 -- only come in a body, but at the same time they do not force the need
1178 -- for a body on their own (SPARK RM 7.1.4(4) and 7.2.2(3)).
1180 Body_Required := Unit_Requires_Body (Id);
1182 if not Body_Required then
1184 -- If the package spec does not require an explicit body, then there
1185 -- are not entities requiring completion in the language sense. Call
1186 -- Check_Completion now to ensure that nested package declarations
1187 -- that require an implicit body get one. (In the case where a body
1188 -- is required, Check_Completion is called at the end of the body's
1189 -- declarative part.)
1193 -- If the package spec does not require an explicit body, then all
1194 -- abstract states declared in nested packages cannot possibly get
1195 -- a proper refinement (SPARK RM 7.2.2(3)). This check is performed
1196 -- only when the compilation unit is the main unit to allow for
1197 -- modular SPARK analysis where packages do not necessarily have
1200 if Is_Comp_Unit then
1201 Check_State_Refinements
1203 Is_Main_Unit => Parent (N) = Cunit (Main_Unit));
1207 -- Set Body_Required indication on the compilation unit node
1209 if Is_Comp_Unit then
1210 Set_Body_Required (Parent (N), Body_Required);
1212 if Legacy_Elaboration_Checks and not Body_Required then
1213 Set_Suppress_Elaboration_Warnings (Id);
1217 End_Package_Scope (Id);
1219 -- For the declaration of a library unit that is a remote types package,
1220 -- check legality rules regarding availability of stream attributes for
1221 -- types that contain non-remote access values. This subprogram performs
1222 -- visibility tests that rely on the fact that we have exited the scope
1225 if Is_Comp_Unit then
1226 Validate_RT_RAT_Component (N);
1229 if Debug_Flag_C then
1231 Write_Str ("<== package spec ");
1232 Write_Name (Chars (Id));
1233 Write_Str (" from ");
1234 Write_Location (Sloc (N));
1237 end Analyze_Package_Declaration;
1239 -----------------------------------
1240 -- Analyze_Package_Specification --
1241 -----------------------------------
1243 -- Note that this code is shared for the analysis of generic package specs
1244 -- (see Sem_Ch12.Analyze_Generic_Package_Declaration for details).
1246 procedure Analyze_Package_Specification (N : Node_Id) is
1247 Id : constant Entity_Id := Defining_Entity (N);
1248 Orig_Decl : constant Node_Id := Original_Node (Parent (N));
1249 Vis_Decls : constant List_Id := Visible_Declarations (N);
1250 Priv_Decls : constant List_Id := Private_Declarations (N);
1253 Public_Child : Boolean;
1255 Private_With_Clauses_Installed : Boolean := False;
1256 -- In Ada 2005, private with_clauses are visible in the private part
1257 -- of a nested package, even if it appears in the public part of the
1258 -- enclosing package. This requires a separate step to install these
1259 -- private_with_clauses, and remove them at the end of the nested
1262 procedure Check_One_Tagged_Type_Or_Extension_At_Most;
1263 -- Issue an error in SPARK mode if a package specification contains
1264 -- more than one tagged type or type extension.
1266 procedure Clear_Constants (Id : Entity_Id; FE : Entity_Id);
1267 -- Clears constant indications (Never_Set_In_Source, Constant_Value, and
1268 -- Is_True_Constant) on all variables that are entities of Id, and on
1269 -- the chain whose first element is FE. A recursive call is made for all
1270 -- packages and generic packages.
1272 procedure Generate_Parent_References;
1273 -- For a child unit, generate references to parent units, for
1274 -- GPS navigation purposes.
1276 function Is_Public_Child (Child, Unit : Entity_Id) return Boolean;
1277 -- Child and Unit are entities of compilation units. True if Child
1278 -- is a public child of Parent as defined in 10.1.1
1280 procedure Inspect_Unchecked_Union_Completion (Decls : List_Id);
1281 -- Reject completion of an incomplete or private type declarations
1282 -- having a known discriminant part by an unchecked union.
1284 procedure Install_Parent_Private_Declarations (Inst_Id : Entity_Id);
1285 -- Given the package entity of a generic package instantiation or
1286 -- formal package whose corresponding generic is a child unit, installs
1287 -- the private declarations of each of the child unit's parents.
1288 -- This has to be done at the point of entering the instance package's
1289 -- private part rather than being done in Sem_Ch12.Install_Parent
1290 -- (which is where the parents' visible declarations are installed).
1292 ------------------------------------------------
1293 -- Check_One_Tagged_Type_Or_Extension_At_Most --
1294 ------------------------------------------------
1296 procedure Check_One_Tagged_Type_Or_Extension_At_Most is
1299 procedure Check_Decls (Decls : List_Id);
1300 -- Check that either Previous is Empty and Decls does not contain
1301 -- more than one tagged type or type extension, or Previous is
1302 -- already set and Decls contains no tagged type or type extension.
1308 procedure Check_Decls (Decls : List_Id) is
1312 Decl := First (Decls);
1313 while Present (Decl) loop
1314 if Nkind (Decl) = N_Full_Type_Declaration
1315 and then Is_Tagged_Type (Defining_Identifier (Decl))
1317 if No (Previous) then
1321 Error_Msg_Sloc := Sloc (Previous);
1322 Check_SPARK_05_Restriction
1323 ("at most one tagged type or type extension allowed",
1324 "\\ previous declaration#",
1333 -- Start of processing for Check_One_Tagged_Type_Or_Extension_At_Most
1337 Check_Decls (Vis_Decls);
1339 if Present (Priv_Decls) then
1340 Check_Decls (Priv_Decls);
1342 end Check_One_Tagged_Type_Or_Extension_At_Most;
1344 ---------------------
1345 -- Clear_Constants --
1346 ---------------------
1348 procedure Clear_Constants (Id : Entity_Id; FE : Entity_Id) is
1352 -- Ignore package renamings, not interesting and they can cause self
1353 -- referential loops in the code below.
1355 if Nkind (Parent (Id)) = N_Package_Renaming_Declaration then
1359 -- Note: in the loop below, the check for Next_Entity pointing back
1360 -- to the package entity may seem odd, but it is needed, because a
1361 -- package can contain a renaming declaration to itself, and such
1362 -- renamings are generated automatically within package instances.
1365 while Present (E) and then E /= Id loop
1366 if Is_Assignable (E) then
1367 Set_Never_Set_In_Source (E, False);
1368 Set_Is_True_Constant (E, False);
1369 Set_Current_Value (E, Empty);
1370 Set_Is_Known_Null (E, False);
1371 Set_Last_Assignment (E, Empty);
1373 if not Can_Never_Be_Null (E) then
1374 Set_Is_Known_Non_Null (E, False);
1377 elsif Is_Package_Or_Generic_Package (E) then
1378 Clear_Constants (E, First_Entity (E));
1379 Clear_Constants (E, First_Private_Entity (E));
1384 end Clear_Constants;
1386 --------------------------------
1387 -- Generate_Parent_References --
1388 --------------------------------
1390 procedure Generate_Parent_References is
1391 Decl : constant Node_Id := Parent (N);
1394 if Id = Cunit_Entity (Main_Unit)
1395 or else Parent (Decl) = Library_Unit (Cunit (Main_Unit))
1397 Generate_Reference (Id, Scope (Id), 'k', False);
1399 elsif not Nkind_In (Unit (Cunit (Main_Unit)), N_Subprogram_Body,
1402 -- If current unit is an ancestor of main unit, generate a
1403 -- reference to its own parent.
1407 Main_Spec : Node_Id := Unit (Cunit (Main_Unit));
1410 if Nkind (Main_Spec) = N_Package_Body then
1411 Main_Spec := Unit (Library_Unit (Cunit (Main_Unit)));
1414 U := Parent_Spec (Main_Spec);
1415 while Present (U) loop
1416 if U = Parent (Decl) then
1417 Generate_Reference (Id, Scope (Id), 'k', False);
1420 elsif Nkind (Unit (U)) = N_Package_Body then
1424 U := Parent_Spec (Unit (U));
1429 end Generate_Parent_References;
1431 ---------------------
1432 -- Is_Public_Child --
1433 ---------------------
1435 function Is_Public_Child (Child, Unit : Entity_Id) return Boolean is
1437 if not Is_Private_Descendant (Child) then
1440 if Child = Unit then
1441 return not Private_Present (
1442 Parent (Unit_Declaration_Node (Child)));
1444 return Is_Public_Child (Scope (Child), Unit);
1447 end Is_Public_Child;
1449 ----------------------------------------
1450 -- Inspect_Unchecked_Union_Completion --
1451 ----------------------------------------
1453 procedure Inspect_Unchecked_Union_Completion (Decls : List_Id) is
1457 Decl := First (Decls);
1458 while Present (Decl) loop
1460 -- We are looking at an incomplete or private type declaration
1461 -- with a known_discriminant_part whose full view is an
1462 -- Unchecked_Union. The seemingly useless check with Is_Type
1463 -- prevents cascaded errors when routines defined only for type
1464 -- entities are called with non-type entities.
1466 if Nkind_In (Decl, N_Incomplete_Type_Declaration,
1467 N_Private_Type_Declaration)
1468 and then Is_Type (Defining_Identifier (Decl))
1469 and then Has_Discriminants (Defining_Identifier (Decl))
1470 and then Present (Full_View (Defining_Identifier (Decl)))
1472 Is_Unchecked_Union (Full_View (Defining_Identifier (Decl)))
1475 ("completion of discriminated partial view "
1476 & "cannot be an unchecked union",
1477 Full_View (Defining_Identifier (Decl)));
1482 end Inspect_Unchecked_Union_Completion;
1484 -----------------------------------------
1485 -- Install_Parent_Private_Declarations --
1486 -----------------------------------------
1488 procedure Install_Parent_Private_Declarations (Inst_Id : Entity_Id) is
1489 Inst_Par : Entity_Id;
1490 Gen_Par : Entity_Id;
1491 Inst_Node : Node_Id;
1494 Inst_Par := Inst_Id;
1497 Generic_Parent (Specification (Unit_Declaration_Node (Inst_Par)));
1498 while Present (Gen_Par) and then Is_Child_Unit (Gen_Par) loop
1499 Inst_Node := Get_Unit_Instantiation_Node (Inst_Par);
1501 if Nkind_In (Inst_Node, N_Package_Instantiation,
1502 N_Formal_Package_Declaration)
1503 and then Nkind (Name (Inst_Node)) = N_Expanded_Name
1505 Inst_Par := Entity (Prefix (Name (Inst_Node)));
1507 if Present (Renamed_Entity (Inst_Par)) then
1508 Inst_Par := Renamed_Entity (Inst_Par);
1513 (Specification (Unit_Declaration_Node (Inst_Par)));
1515 -- Install the private declarations and private use clauses
1516 -- of a parent instance of the child instance, unless the
1517 -- parent instance private declarations have already been
1518 -- installed earlier in Analyze_Package_Specification, which
1519 -- happens when a generic child is instantiated, and the
1520 -- instance is a child of the parent instance.
1522 -- Installing the use clauses of the parent instance twice
1523 -- is both unnecessary and wrong, because it would cause the
1524 -- clauses to be chained to themselves in the use clauses
1525 -- list of the scope stack entry. That in turn would cause
1526 -- an endless loop from End_Use_Clauses upon scope exit.
1528 -- The parent is now fully visible. It may be a hidden open
1529 -- scope if we are currently compiling some child instance
1530 -- declared within it, but while the current instance is being
1531 -- compiled the parent is immediately visible. In particular
1532 -- its entities must remain visible if a stack save/restore
1533 -- takes place through a call to Rtsfind.
1535 if Present (Gen_Par) then
1536 if not In_Private_Part (Inst_Par) then
1537 Install_Private_Declarations (Inst_Par);
1538 Set_Use (Private_Declarations
1540 (Unit_Declaration_Node (Inst_Par))));
1541 Set_Is_Hidden_Open_Scope (Inst_Par, False);
1544 -- If we've reached the end of the generic instance parents,
1545 -- then finish off by looping through the nongeneric parents
1546 -- and installing their private declarations.
1548 -- If one of the non-generic parents is itself on the scope
1549 -- stack, do not install its private declarations: they are
1550 -- installed in due time when the private part of that parent
1554 while Present (Inst_Par)
1555 and then Inst_Par /= Standard_Standard
1556 and then (not In_Open_Scopes (Inst_Par)
1557 or else not In_Private_Part (Inst_Par))
1559 if Nkind (Inst_Node) = N_Formal_Package_Declaration
1561 not Is_Ancestor_Package
1562 (Inst_Par, Cunit_Entity (Current_Sem_Unit))
1564 Install_Private_Declarations (Inst_Par);
1566 (Private_Declarations
1568 (Unit_Declaration_Node (Inst_Par))));
1569 Inst_Par := Scope (Inst_Par);
1582 end Install_Parent_Private_Declarations;
1584 -- Start of processing for Analyze_Package_Specification
1587 if Present (Vis_Decls) then
1588 Analyze_Declarations (Vis_Decls);
1591 -- Inspect the entities defined in the package and ensure that all
1592 -- incomplete types have received full declarations. Build default
1593 -- initial condition and invariant procedures for all qualifying types.
1595 E := First_Entity (Id);
1596 while Present (E) loop
1598 -- Check on incomplete types
1600 -- AI05-0213: A formal incomplete type has no completion, and neither
1601 -- does the corresponding subtype in an instance.
1603 if Is_Incomplete_Type (E)
1604 and then No (Full_View (E))
1605 and then not Is_Generic_Type (E)
1606 and then not From_Limited_With (E)
1607 and then not Is_Generic_Actual_Type (E)
1609 Error_Msg_N ("no declaration in visible part for incomplete}", E);
1615 if Is_Remote_Call_Interface (Id)
1616 and then Nkind (Parent (Parent (N))) = N_Compilation_Unit
1618 Validate_RCI_Declarations (Id);
1621 -- Save global references in the visible declarations, before installing
1622 -- private declarations of parent unit if there is one, because the
1623 -- privacy status of types defined in the parent will change. This is
1624 -- only relevant for generic child units, but is done in all cases for
1627 if Ekind (Id) = E_Generic_Package
1628 and then Nkind (Orig_Decl) = N_Generic_Package_Declaration
1631 Orig_Spec : constant Node_Id := Specification (Orig_Decl);
1632 Save_Priv : constant List_Id := Private_Declarations (Orig_Spec);
1635 -- Insert the freezing nodes after the visible declarations to
1636 -- ensure that we analyze its aspects; needed to ensure that
1637 -- global entities referenced in the aspects are properly handled.
1639 if Ada_Version >= Ada_2012
1640 and then Is_Non_Empty_List (Vis_Decls)
1641 and then Is_Empty_List (Priv_Decls)
1643 Insert_List_After_And_Analyze
1644 (Last (Vis_Decls), Freeze_Entity (Id, Last (Vis_Decls)));
1647 Set_Private_Declarations (Orig_Spec, Empty_List);
1648 Save_Global_References (Orig_Decl);
1649 Set_Private_Declarations (Orig_Spec, Save_Priv);
1653 -- If package is a public child unit, then make the private declarations
1654 -- of the parent visible.
1656 Public_Child := False;
1660 Pack_Decl : Node_Id;
1665 Par_Spec := Parent_Spec (Parent (N));
1667 -- If the package is formal package of an enclosing generic, it is
1668 -- transformed into a local generic declaration, and compiled to make
1669 -- its spec available. We need to retrieve the original generic to
1670 -- determine whether it is a child unit, and install its parents.
1674 Nkind (Original_Node (Parent (N))) = N_Formal_Package_Declaration
1676 Par := Entity (Name (Original_Node (Parent (N))));
1677 Par_Spec := Parent_Spec (Unit_Declaration_Node (Par));
1680 if Present (Par_Spec) then
1681 Generate_Parent_References;
1683 while Scope (Par) /= Standard_Standard
1684 and then Is_Public_Child (Id, Par)
1685 and then In_Open_Scopes (Par)
1687 Public_Child := True;
1689 Install_Private_Declarations (Par);
1690 Install_Private_With_Clauses (Par);
1691 Pack_Decl := Unit_Declaration_Node (Par);
1692 Set_Use (Private_Declarations (Specification (Pack_Decl)));
1697 if Is_Compilation_Unit (Id) then
1698 Install_Private_With_Clauses (Id);
1700 -- The current compilation unit may include private with_clauses,
1701 -- which are visible in the private part of the current nested
1702 -- package, and have to be installed now. This is not done for
1703 -- nested instantiations, where the private with_clauses of the
1704 -- enclosing unit have no effect once the instantiation info is
1705 -- established and we start analyzing the package declaration.
1708 Comp_Unit : constant Entity_Id := Cunit_Entity (Current_Sem_Unit);
1710 if Is_Package_Or_Generic_Package (Comp_Unit)
1711 and then not In_Private_Part (Comp_Unit)
1712 and then not In_Instance
1714 Install_Private_With_Clauses (Comp_Unit);
1715 Private_With_Clauses_Installed := True;
1720 -- If this is a package associated with a generic instance or formal
1721 -- package, then the private declarations of each of the generic's
1722 -- parents must be installed at this point.
1724 if Is_Generic_Instance (Id) then
1725 Install_Parent_Private_Declarations (Id);
1728 -- Analyze private part if present. The flag In_Private_Part is reset
1729 -- in End_Package_Scope.
1731 L := Last_Entity (Id);
1733 if Present (Priv_Decls) then
1734 Set_In_Private_Part (Id);
1736 -- Upon entering a public child's private part, it may be necessary
1737 -- to declare subprograms that were derived in the package's visible
1738 -- part but not yet made visible.
1740 if Public_Child then
1741 Declare_Inherited_Private_Subprograms (Id);
1744 Analyze_Declarations (Priv_Decls);
1746 -- Check the private declarations for incomplete deferred constants
1748 Inspect_Deferred_Constant_Completion (Priv_Decls);
1750 -- The first private entity is the immediate follower of the last
1751 -- visible entity, if there was one.
1754 Set_First_Private_Entity (Id, Next_Entity (L));
1756 Set_First_Private_Entity (Id, First_Entity (Id));
1759 -- There may be inherited private subprograms that need to be declared,
1760 -- even in the absence of an explicit private part. If there are any
1761 -- public declarations in the package and the package is a public child
1762 -- unit, then an implicit private part is assumed.
1764 elsif Present (L) and then Public_Child then
1765 Set_In_Private_Part (Id);
1766 Declare_Inherited_Private_Subprograms (Id);
1767 Set_First_Private_Entity (Id, Next_Entity (L));
1770 E := First_Entity (Id);
1771 while Present (E) loop
1773 -- Check rule of 3.6(11), which in general requires waiting till all
1774 -- full types have been seen.
1776 if Ekind (E) = E_Record_Type or else Ekind (E) = E_Array_Type then
1777 Check_Aliased_Component_Types (E);
1780 -- Check preelaborable initialization for full type completing a
1781 -- private type for which pragma Preelaborable_Initialization given.
1784 and then Must_Have_Preelab_Init (E)
1785 and then not Has_Preelaborable_Initialization (E)
1788 ("full view of & does not have preelaborable initialization", E);
1794 -- Ada 2005 (AI-216): The completion of an incomplete or private type
1795 -- declaration having a known_discriminant_part shall not be an
1796 -- unchecked union type.
1798 if Present (Vis_Decls) then
1799 Inspect_Unchecked_Union_Completion (Vis_Decls);
1802 if Present (Priv_Decls) then
1803 Inspect_Unchecked_Union_Completion (Priv_Decls);
1806 if Ekind (Id) = E_Generic_Package
1807 and then Nkind (Orig_Decl) = N_Generic_Package_Declaration
1808 and then Present (Priv_Decls)
1810 -- Save global references in private declarations, ignoring the
1811 -- visible declarations that were processed earlier.
1814 Orig_Spec : constant Node_Id := Specification (Orig_Decl);
1815 Save_Vis : constant List_Id := Visible_Declarations (Orig_Spec);
1816 Save_Form : constant List_Id :=
1817 Generic_Formal_Declarations (Orig_Decl);
1820 -- Insert the freezing nodes after the private declarations to
1821 -- ensure that we analyze its aspects; needed to ensure that
1822 -- global entities referenced in the aspects are properly handled.
1824 if Ada_Version >= Ada_2012
1825 and then Is_Non_Empty_List (Priv_Decls)
1827 Insert_List_After_And_Analyze
1828 (Last (Priv_Decls), Freeze_Entity (Id, Last (Priv_Decls)));
1831 Set_Visible_Declarations (Orig_Spec, Empty_List);
1832 Set_Generic_Formal_Declarations (Orig_Decl, Empty_List);
1833 Save_Global_References (Orig_Decl);
1834 Set_Generic_Formal_Declarations (Orig_Decl, Save_Form);
1835 Set_Visible_Declarations (Orig_Spec, Save_Vis);
1839 Process_End_Label (N, 'e', Id);
1841 -- Remove private_with_clauses of enclosing compilation unit, if they
1844 if Private_With_Clauses_Installed then
1845 Remove_Private_With_Clauses (Cunit (Current_Sem_Unit));
1848 -- For the case of a library level package, we must go through all the
1849 -- entities clearing the indications that the value may be constant and
1850 -- not modified. Why? Because any client of this package may modify
1851 -- these values freely from anywhere. This also applies to any nested
1852 -- packages or generic packages.
1854 -- For now we unconditionally clear constants for packages that are
1855 -- instances of generic packages. The reason is that we do not have the
1856 -- body yet, and we otherwise think things are unreferenced when they
1857 -- are not. This should be fixed sometime (the effect is not terrible,
1858 -- we just lose some warnings, and also some cases of value propagation)
1861 if Is_Library_Level_Entity (Id)
1862 or else Is_Generic_Instance (Id)
1864 Clear_Constants (Id, First_Entity (Id));
1865 Clear_Constants (Id, First_Private_Entity (Id));
1868 -- Issue an error in SPARK mode if a package specification contains
1869 -- more than one tagged type or type extension.
1871 Check_One_Tagged_Type_Or_Extension_At_Most;
1873 -- Output relevant information as to why the package requires a body.
1874 -- Do not consider generated packages as this exposes internal symbols
1875 -- and leads to confusing messages.
1877 if List_Body_Required_Info
1878 and then In_Extended_Main_Source_Unit (Id)
1879 and then Unit_Requires_Body (Id)
1880 and then Comes_From_Source (Id)
1882 Unit_Requires_Body_Info (Id);
1885 -- Nested package specs that do not require bodies are not checked for
1886 -- ineffective use clauses due to the possibility of subunits. This is
1887 -- because at this stage it is impossible to tell whether there will be
1890 if not Unit_Requires_Body (Id)
1891 and then Is_Compilation_Unit (Id)
1892 and then not Is_Private_Descendant (Id)
1894 Update_Use_Clause_Chain;
1896 end Analyze_Package_Specification;
1898 --------------------------------------
1899 -- Analyze_Private_Type_Declaration --
1900 --------------------------------------
1902 procedure Analyze_Private_Type_Declaration (N : Node_Id) is
1903 Id : constant Entity_Id := Defining_Identifier (N);
1904 PF : constant Boolean := Is_Pure (Enclosing_Lib_Unit_Entity);
1907 Generate_Definition (Id);
1908 Set_Is_Pure (Id, PF);
1909 Init_Size_Align (Id);
1911 if not Is_Package_Or_Generic_Package (Current_Scope)
1912 or else In_Private_Part (Current_Scope)
1914 Error_Msg_N ("invalid context for private declaration", N);
1917 New_Private_Type (N, Id, N);
1918 Set_Depends_On_Private (Id);
1920 -- Set the SPARK mode from the current context
1922 Set_SPARK_Pragma (Id, SPARK_Mode_Pragma);
1923 Set_SPARK_Pragma_Inherited (Id);
1925 if Has_Aspects (N) then
1926 Analyze_Aspect_Specifications (N, Id);
1928 end Analyze_Private_Type_Declaration;
1930 ----------------------------------
1931 -- Check_Anonymous_Access_Types --
1932 ----------------------------------
1934 procedure Check_Anonymous_Access_Types
1935 (Spec_Id : Entity_Id;
1942 -- Itype references are only needed by gigi, to force elaboration of
1943 -- itypes. In the absence of code generation, they are not needed.
1945 if not Expander_Active then
1949 E := First_Entity (Spec_Id);
1950 while Present (E) loop
1951 if Ekind (E) = E_Anonymous_Access_Type
1952 and then From_Limited_With (E)
1954 IR := Make_Itype_Reference (Sloc (P_Body));
1957 if No (Declarations (P_Body)) then
1958 Set_Declarations (P_Body, New_List (IR));
1960 Prepend (IR, Declarations (P_Body));
1966 end Check_Anonymous_Access_Types;
1968 -------------------------------------------
1969 -- Declare_Inherited_Private_Subprograms --
1970 -------------------------------------------
1972 procedure Declare_Inherited_Private_Subprograms (Id : Entity_Id) is
1974 function Is_Primitive_Of (T : Entity_Id; S : Entity_Id) return Boolean;
1975 -- Check whether an inherited subprogram S is an operation of an
1976 -- untagged derived type T.
1978 ---------------------
1979 -- Is_Primitive_Of --
1980 ---------------------
1982 function Is_Primitive_Of (T : Entity_Id; S : Entity_Id) return Boolean is
1986 -- If the full view is a scalar type, the type is the anonymous base
1987 -- type, but the operation mentions the first subtype, so check the
1988 -- signature against the base type.
1990 if Base_Type (Etype (S)) = Base_Type (T) then
1994 Formal := First_Formal (S);
1995 while Present (Formal) loop
1996 if Base_Type (Etype (Formal)) = Base_Type (T) then
2000 Next_Formal (Formal);
2005 end Is_Primitive_Of;
2012 Op_Elmt_2 : Elmt_Id;
2013 Prim_Op : Entity_Id;
2014 New_Op : Entity_Id := Empty;
2015 Parent_Subp : Entity_Id;
2018 -- Start of processing for Declare_Inherited_Private_Subprograms
2021 E := First_Entity (Id);
2022 while Present (E) loop
2024 -- If the entity is a nonprivate type extension whose parent type
2025 -- is declared in an open scope, then the type may have inherited
2026 -- operations that now need to be made visible. Ditto if the entity
2027 -- is a formal derived type in a child unit.
2029 if ((Is_Derived_Type (E) and then not Is_Private_Type (E))
2031 (Nkind (Parent (E)) = N_Private_Extension_Declaration
2032 and then Is_Generic_Type (E)))
2033 and then In_Open_Scopes (Scope (Etype (E)))
2034 and then Is_Base_Type (E)
2036 if Is_Tagged_Type (E) then
2037 Op_List := Primitive_Operations (E);
2039 Tag := First_Tag_Component (E);
2041 Op_Elmt := First_Elmt (Op_List);
2042 while Present (Op_Elmt) loop
2043 Prim_Op := Node (Op_Elmt);
2045 -- Search primitives that are implicit operations with an
2046 -- internal name whose parent operation has a normal name.
2048 if Present (Alias (Prim_Op))
2049 and then Find_Dispatching_Type (Alias (Prim_Op)) /= E
2050 and then not Comes_From_Source (Prim_Op)
2051 and then Is_Internal_Name (Chars (Prim_Op))
2052 and then not Is_Internal_Name (Chars (Alias (Prim_Op)))
2054 Parent_Subp := Alias (Prim_Op);
2056 -- Case 1: Check if the type has also an explicit
2057 -- overriding for this primitive.
2059 Op_Elmt_2 := Next_Elmt (Op_Elmt);
2060 while Present (Op_Elmt_2) loop
2062 -- Skip entities with attribute Interface_Alias since
2063 -- they are not overriding primitives (these entities
2064 -- link an interface primitive with their covering
2067 if Chars (Node (Op_Elmt_2)) = Chars (Parent_Subp)
2068 and then Type_Conformant (Prim_Op, Node (Op_Elmt_2))
2069 and then No (Interface_Alias (Node (Op_Elmt_2)))
2071 -- The private inherited operation has been
2072 -- overridden by an explicit subprogram:
2073 -- replace the former by the latter.
2075 New_Op := Node (Op_Elmt_2);
2076 Replace_Elmt (Op_Elmt, New_Op);
2077 Remove_Elmt (Op_List, Op_Elmt_2);
2078 Set_Overridden_Operation (New_Op, Parent_Subp);
2080 -- We don't need to inherit its dispatching slot.
2081 -- Set_All_DT_Position has previously ensured that
2082 -- the same slot was assigned to the two primitives
2085 and then Present (DTC_Entity (New_Op))
2086 and then Present (DTC_Entity (Prim_Op))
2089 (DT_Position (New_Op) = DT_Position (Prim_Op));
2093 goto Next_Primitive;
2096 Next_Elmt (Op_Elmt_2);
2099 -- Case 2: We have not found any explicit overriding and
2100 -- hence we need to declare the operation (i.e., make it
2103 Derive_Subprogram (New_Op, Alias (Prim_Op), E, Etype (E));
2105 -- Inherit the dispatching slot if E is already frozen
2108 and then Present (DTC_Entity (Alias (Prim_Op)))
2110 Set_DTC_Entity_Value (E, New_Op);
2111 Set_DT_Position_Value (New_Op,
2112 DT_Position (Alias (Prim_Op)));
2116 (Is_Dispatching_Operation (New_Op)
2117 and then Node (Last_Elmt (Op_List)) = New_Op);
2119 -- Substitute the new operation for the old one in the
2120 -- type's primitive operations list. Since the new
2121 -- operation was also just added to the end of list,
2122 -- the last element must be removed.
2124 -- (Question: is there a simpler way of declaring the
2125 -- operation, say by just replacing the name of the
2126 -- earlier operation, reentering it in the in the symbol
2127 -- table (how?), and marking it as private???)
2129 Replace_Elmt (Op_Elmt, New_Op);
2130 Remove_Last_Elmt (Op_List);
2134 Next_Elmt (Op_Elmt);
2137 -- Generate listing showing the contents of the dispatch table
2139 if Debug_Flag_ZZ then
2144 -- For untagged type, scan forward to locate inherited hidden
2147 Prim_Op := Next_Entity (E);
2148 while Present (Prim_Op) loop
2149 if Is_Subprogram (Prim_Op)
2150 and then Present (Alias (Prim_Op))
2151 and then not Comes_From_Source (Prim_Op)
2152 and then Is_Internal_Name (Chars (Prim_Op))
2153 and then not Is_Internal_Name (Chars (Alias (Prim_Op)))
2154 and then Is_Primitive_Of (E, Prim_Op)
2156 Derive_Subprogram (New_Op, Alias (Prim_Op), E, Etype (E));
2159 Next_Entity (Prim_Op);
2161 -- Derived operations appear immediately after the type
2162 -- declaration (or the following subtype indication for
2163 -- a derived scalar type). Further declarations cannot
2164 -- include inherited operations of the type.
2166 if Present (Prim_Op) then
2167 exit when Ekind (Prim_Op) not in Overloadable_Kind;
2175 end Declare_Inherited_Private_Subprograms;
2177 -----------------------
2178 -- End_Package_Scope --
2179 -----------------------
2181 procedure End_Package_Scope (P : Entity_Id) is
2183 Uninstall_Declarations (P);
2185 end End_Package_Scope;
2187 ---------------------------
2188 -- Exchange_Declarations --
2189 ---------------------------
2191 procedure Exchange_Declarations (Id : Entity_Id) is
2192 Full_Id : constant Entity_Id := Full_View (Id);
2193 H1 : constant Entity_Id := Homonym (Id);
2194 Next1 : constant Entity_Id := Next_Entity (Id);
2199 -- If missing full declaration for type, nothing to exchange
2201 if No (Full_Id) then
2205 -- Otherwise complete the exchange, and preserve semantic links
2207 Next2 := Next_Entity (Full_Id);
2208 H2 := Homonym (Full_Id);
2210 -- Reset full declaration pointer to reflect the switched entities and
2211 -- readjust the next entity chains.
2213 Exchange_Entities (Id, Full_Id);
2215 Link_Entities (Id, Next1);
2216 Set_Homonym (Id, H1);
2218 Set_Full_View (Full_Id, Id);
2219 Link_Entities (Full_Id, Next2);
2220 Set_Homonym (Full_Id, H2);
2221 end Exchange_Declarations;
2223 ----------------------------
2224 -- Install_Package_Entity --
2225 ----------------------------
2227 procedure Install_Package_Entity (Id : Entity_Id) is
2229 if not Is_Internal (Id) then
2230 if Debug_Flag_E then
2231 Write_Str ("Install: ");
2232 Write_Name (Chars (Id));
2236 if Is_Child_Unit (Id) then
2239 -- Do not enter implicitly inherited non-overridden subprograms of
2240 -- a tagged type back into visibility if they have non-conformant
2241 -- homographs (Ada RM 8.3 12.3/2).
2243 elsif Is_Hidden_Non_Overridden_Subpgm (Id) then
2247 Set_Is_Immediately_Visible (Id);
2250 end Install_Package_Entity;
2252 ----------------------------------
2253 -- Install_Private_Declarations --
2254 ----------------------------------
2256 procedure Install_Private_Declarations (P : Entity_Id) is
2259 Priv_Deps : Elist_Id;
2261 procedure Swap_Private_Dependents (Priv_Deps : Elist_Id);
2262 -- When the full view of a private type is made available, we do the
2263 -- same for its private dependents under proper visibility conditions.
2264 -- When compiling a child unit this needs to be done recursively.
2266 -----------------------------
2267 -- Swap_Private_Dependents --
2268 -----------------------------
2270 procedure Swap_Private_Dependents (Priv_Deps : Elist_Id) is
2274 Priv_Elmt : Elmt_Id;
2278 Priv_Elmt := First_Elmt (Priv_Deps);
2279 while Present (Priv_Elmt) loop
2280 Priv := Node (Priv_Elmt);
2282 -- Before the exchange, verify that the presence of the Full_View
2283 -- field. This field will be empty if the entity has already been
2284 -- installed due to a previous call.
2286 if Present (Full_View (Priv)) and then Is_Visible_Dependent (Priv)
2288 if Is_Private_Type (Priv) then
2289 Cunit := Cunit_Entity (Current_Sem_Unit);
2290 Deps := Private_Dependents (Priv);
2296 -- For each subtype that is swapped, we also swap the reference
2297 -- to it in Private_Dependents, to allow access to it when we
2298 -- swap them out in End_Package_Scope.
2300 Replace_Elmt (Priv_Elmt, Full_View (Priv));
2302 -- Ensure that both views of the dependent private subtype are
2303 -- immediately visible if within some open scope. Check full
2304 -- view before exchanging views.
2306 if In_Open_Scopes (Scope (Full_View (Priv))) then
2307 Set_Is_Immediately_Visible (Priv);
2310 Exchange_Declarations (Priv);
2311 Set_Is_Immediately_Visible
2312 (Priv, In_Open_Scopes (Scope (Priv)));
2314 Set_Is_Potentially_Use_Visible
2315 (Priv, Is_Potentially_Use_Visible (Node (Priv_Elmt)));
2317 -- Recurse for child units, except in generic child units,
2318 -- which unfortunately handle private_dependents separately.
2319 -- Note that the current unit may not have been analyzed,
2320 -- for example a package body, so we cannot rely solely on
2321 -- the Is_Child_Unit flag, but that's only an optimization.
2324 and then (No (Etype (Cunit)) or else Is_Child_Unit (Cunit))
2325 and then not Is_Empty_Elmt_List (Deps)
2326 and then not Inside_A_Generic
2328 Swap_Private_Dependents (Deps);
2332 Next_Elmt (Priv_Elmt);
2334 end Swap_Private_Dependents;
2336 -- Start of processing for Install_Private_Declarations
2339 -- First exchange declarations for private types, so that the full
2340 -- declaration is visible. For each private type, we check its
2341 -- Private_Dependents list and also exchange any subtypes of or derived
2342 -- types from it. Finally, if this is a Taft amendment type, the
2343 -- incomplete declaration is irrelevant, and we want to link the
2344 -- eventual full declaration with the original private one so we
2345 -- also skip the exchange.
2347 Id := First_Entity (P);
2348 while Present (Id) and then Id /= First_Private_Entity (P) loop
2349 if Is_Private_Base_Type (Id)
2350 and then Present (Full_View (Id))
2351 and then Comes_From_Source (Full_View (Id))
2352 and then Scope (Full_View (Id)) = Scope (Id)
2353 and then Ekind (Full_View (Id)) /= E_Incomplete_Type
2355 -- If there is a use-type clause on the private type, set the full
2356 -- view accordingly.
2358 Set_In_Use (Full_View (Id), In_Use (Id));
2359 Full := Full_View (Id);
2361 if Is_Private_Base_Type (Full)
2362 and then Has_Private_Declaration (Full)
2363 and then Nkind (Parent (Full)) = N_Full_Type_Declaration
2364 and then In_Open_Scopes (Scope (Etype (Full)))
2365 and then In_Package_Body (Current_Scope)
2366 and then not Is_Private_Type (Etype (Full))
2368 -- This is the completion of a private type by a derivation
2369 -- from another private type which is not private anymore. This
2370 -- can only happen in a package nested within a child package,
2371 -- when the parent type is defined in the parent unit. At this
2372 -- point the current type is not private either, and we have
2373 -- to install the underlying full view, which is now visible.
2374 -- Save the current full view as well, so that all views can be
2375 -- restored on exit. It may seem that after compiling the child
2376 -- body there are not environments to restore, but the back-end
2377 -- expects those links to be valid, and freeze nodes depend on
2380 if No (Full_View (Full))
2381 and then Present (Underlying_Full_View (Full))
2383 Set_Full_View (Id, Underlying_Full_View (Full));
2384 Set_Underlying_Full_View (Id, Full);
2385 Set_Is_Underlying_Full_View (Full);
2387 Set_Underlying_Full_View (Full, Empty);
2388 Set_Is_Frozen (Full_View (Id));
2392 Priv_Deps := Private_Dependents (Id);
2393 Exchange_Declarations (Id);
2394 Set_Is_Immediately_Visible (Id);
2395 Swap_Private_Dependents (Priv_Deps);
2401 -- Next make other declarations in the private part visible as well
2403 Id := First_Private_Entity (P);
2404 while Present (Id) loop
2405 Install_Package_Entity (Id);
2406 Set_Is_Hidden (Id, False);
2410 -- An abstract state is partially refined when it has at least one
2411 -- Part_Of constituent. Since these constituents are being installed
2412 -- into visibility, update the partial refinement status of any state
2413 -- defined in the associated package, subject to at least one Part_Of
2416 if Ekind_In (P, E_Generic_Package, E_Package) then
2418 States : constant Elist_Id := Abstract_States (P);
2419 State_Elmt : Elmt_Id;
2420 State_Id : Entity_Id;
2423 if Present (States) then
2424 State_Elmt := First_Elmt (States);
2425 while Present (State_Elmt) loop
2426 State_Id := Node (State_Elmt);
2428 if Present (Part_Of_Constituents (State_Id)) then
2429 Set_Has_Partial_Visible_Refinement (State_Id);
2432 Next_Elmt (State_Elmt);
2438 -- Indicate that the private part is currently visible, so it can be
2439 -- properly reset on exit.
2441 Set_In_Private_Part (P);
2442 end Install_Private_Declarations;
2444 ----------------------------------
2445 -- Install_Visible_Declarations --
2446 ----------------------------------
2448 procedure Install_Visible_Declarations (P : Entity_Id) is
2450 Last_Entity : Entity_Id;
2454 (Is_Package_Or_Generic_Package (P) or else Is_Record_Type (P));
2456 if Is_Package_Or_Generic_Package (P) then
2457 Last_Entity := First_Private_Entity (P);
2459 Last_Entity := Empty;
2462 Id := First_Entity (P);
2463 while Present (Id) and then Id /= Last_Entity loop
2464 Install_Package_Entity (Id);
2467 end Install_Visible_Declarations;
2469 --------------------------
2470 -- Is_Private_Base_Type --
2471 --------------------------
2473 function Is_Private_Base_Type (E : Entity_Id) return Boolean is
2475 return Ekind (E) = E_Private_Type
2476 or else Ekind (E) = E_Limited_Private_Type
2477 or else Ekind (E) = E_Record_Type_With_Private;
2478 end Is_Private_Base_Type;
2480 --------------------------
2481 -- Is_Visible_Dependent --
2482 --------------------------
2484 function Is_Visible_Dependent (Dep : Entity_Id) return Boolean
2486 S : constant Entity_Id := Scope (Dep);
2489 -- Renamings created for actual types have the visibility of the actual
2491 if Ekind (S) = E_Package
2492 and then Is_Generic_Instance (S)
2493 and then (Is_Generic_Actual_Type (Dep)
2494 or else Is_Generic_Actual_Type (Full_View (Dep)))
2498 elsif not (Is_Derived_Type (Dep))
2499 and then Is_Derived_Type (Full_View (Dep))
2501 -- When instantiating a package body, the scope stack is empty, so
2502 -- check instead whether the dependent type is defined in the same
2503 -- scope as the instance itself.
2505 return In_Open_Scopes (S)
2506 or else (Is_Generic_Instance (Current_Scope)
2507 and then Scope (Dep) = Scope (Current_Scope));
2511 end Is_Visible_Dependent;
2513 ----------------------------
2514 -- May_Need_Implicit_Body --
2515 ----------------------------
2517 procedure May_Need_Implicit_Body (E : Entity_Id) is
2518 P : constant Node_Id := Unit_Declaration_Node (E);
2519 S : constant Node_Id := Parent (P);
2524 if not Has_Completion (E)
2525 and then Nkind (P) = N_Package_Declaration
2526 and then (Present (Activation_Chain_Entity (P)) or else Has_RACW (E))
2529 Make_Package_Body (Sloc (E),
2530 Defining_Unit_Name => Make_Defining_Identifier (Sloc (E),
2531 Chars => Chars (E)),
2532 Declarations => New_List);
2534 if Nkind (S) = N_Package_Specification then
2535 if Present (Private_Declarations (S)) then
2536 Decls := Private_Declarations (S);
2538 Decls := Visible_Declarations (S);
2541 Decls := Declarations (S);
2547 end May_Need_Implicit_Body;
2549 ----------------------
2550 -- New_Private_Type --
2551 ----------------------
2553 procedure New_Private_Type (N : Node_Id; Id : Entity_Id; Def : Node_Id) is
2555 -- For other than Ada 2012, enter the name in the current scope
2557 if Ada_Version < Ada_2012 then
2560 -- Ada 2012 (AI05-0162): Enter the name in the current scope. Note that
2561 -- there may be an incomplete previous view.
2567 Prev := Find_Type_Name (N);
2568 pragma Assert (Prev = Id
2569 or else (Ekind (Prev) = E_Incomplete_Type
2570 and then Present (Full_View (Prev))
2571 and then Full_View (Prev) = Id));
2575 if Limited_Present (Def) then
2576 Set_Ekind (Id, E_Limited_Private_Type);
2578 Set_Ekind (Id, E_Private_Type);
2582 Set_Has_Delayed_Freeze (Id);
2583 Set_Is_First_Subtype (Id);
2584 Init_Size_Align (Id);
2586 Set_Is_Constrained (Id,
2587 No (Discriminant_Specifications (N))
2588 and then not Unknown_Discriminants_Present (N));
2590 -- Set tagged flag before processing discriminants, to catch illegal
2593 Set_Is_Tagged_Type (Id, Tagged_Present (Def));
2595 Set_Discriminant_Constraint (Id, No_Elist);
2596 Set_Stored_Constraint (Id, No_Elist);
2598 if Present (Discriminant_Specifications (N)) then
2600 Process_Discriminants (N);
2603 elsif Unknown_Discriminants_Present (N) then
2604 Set_Has_Unknown_Discriminants (Id);
2607 Set_Private_Dependents (Id, New_Elmt_List);
2609 if Tagged_Present (Def) then
2610 Set_Ekind (Id, E_Record_Type_With_Private);
2611 Set_Direct_Primitive_Operations (Id, New_Elmt_List);
2612 Set_Is_Abstract_Type (Id, Abstract_Present (Def));
2613 Set_Is_Limited_Record (Id, Limited_Present (Def));
2614 Set_Has_Delayed_Freeze (Id, True);
2616 -- Recognize Ada.Real_Time.Timing_Events.Timing_Events here
2618 if Is_RTE (Id, RE_Timing_Event) then
2619 Set_Has_Timing_Event (Id);
2622 -- Create a class-wide type with the same attributes
2624 Make_Class_Wide_Type (Id);
2626 elsif Abstract_Present (Def) then
2627 Error_Msg_N ("only a tagged type can be abstract", N);
2629 end New_Private_Type;
2631 ---------------------------------
2632 -- Requires_Completion_In_Body --
2633 ---------------------------------
2635 function Requires_Completion_In_Body
2637 Pack_Id : Entity_Id;
2638 Do_Abstract_States : Boolean := False) return Boolean
2641 -- Always ignore child units. Child units get added to the entity list
2642 -- of a parent unit, but are not original entities of the parent, and
2643 -- so do not affect whether the parent needs a body.
2645 if Is_Child_Unit (Id) then
2648 -- Ignore formal packages and their renamings
2650 elsif Ekind (Id) = E_Package
2651 and then Nkind (Original_Node (Unit_Declaration_Node (Id))) =
2652 N_Formal_Package_Declaration
2656 -- Otherwise test to see if entity requires a completion. Note that
2657 -- subprogram entities whose declaration does not come from source are
2658 -- ignored here on the basis that we assume the expander will provide an
2659 -- implicit completion at some point.
2661 elsif (Is_Overloadable (Id)
2662 and then not Ekind_In (Id, E_Enumeration_Literal, E_Operator)
2663 and then not Is_Abstract_Subprogram (Id)
2664 and then not Has_Completion (Id)
2665 and then Comes_From_Source (Parent (Id)))
2668 (Ekind (Id) = E_Package
2669 and then Id /= Pack_Id
2670 and then not Has_Completion (Id)
2671 and then Unit_Requires_Body (Id, Do_Abstract_States))
2674 (Ekind (Id) = E_Incomplete_Type
2675 and then No (Full_View (Id))
2676 and then not Is_Generic_Type (Id))
2679 (Ekind_In (Id, E_Task_Type, E_Protected_Type)
2680 and then not Has_Completion (Id))
2683 (Ekind (Id) = E_Generic_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 (Is_Generic_Subprogram (Id)
2690 and then not Has_Completion (Id))
2694 -- Otherwise the entity does not require completion in a package body
2699 end Requires_Completion_In_Body;
2701 ----------------------------
2702 -- Uninstall_Declarations --
2703 ----------------------------
2705 procedure Uninstall_Declarations (P : Entity_Id) is
2706 Decl : constant Node_Id := Unit_Declaration_Node (P);
2710 procedure Preserve_Full_Attributes (Priv : Entity_Id; Full : Entity_Id);
2711 -- Copy to the private declaration the attributes of the full view that
2712 -- need to be available for the partial view also.
2714 procedure Swap_Private_Dependents (Priv_Deps : Elist_Id);
2715 -- When the full view of a private type is made unavailable, we do the
2716 -- same for its private dependents under proper visibility conditions.
2717 -- When compiling a child unit this needs to be done recursively.
2719 function Type_In_Use (T : Entity_Id) return Boolean;
2720 -- Check whether type or base type appear in an active use_type clause
2722 ------------------------------
2723 -- Preserve_Full_Attributes --
2724 ------------------------------
2726 procedure Preserve_Full_Attributes
2730 Full_Base : constant Entity_Id := Base_Type (Full);
2731 Priv_Is_Base_Type : constant Boolean := Is_Base_Type (Priv);
2734 Set_Size_Info (Priv, Full);
2735 Set_RM_Size (Priv, RM_Size (Full));
2736 Set_Size_Known_At_Compile_Time
2737 (Priv, Size_Known_At_Compile_Time (Full));
2738 Set_Is_Volatile (Priv, Is_Volatile (Full));
2739 Set_Treat_As_Volatile (Priv, Treat_As_Volatile (Full));
2740 Set_Is_Ada_2005_Only (Priv, Is_Ada_2005_Only (Full));
2741 Set_Is_Ada_2012_Only (Priv, Is_Ada_2012_Only (Full));
2742 Set_Has_Pragma_Unmodified (Priv, Has_Pragma_Unmodified (Full));
2743 Set_Has_Pragma_Unreferenced (Priv, Has_Pragma_Unreferenced (Full));
2744 Set_Has_Pragma_Unreferenced_Objects
2745 (Priv, Has_Pragma_Unreferenced_Objects
2747 if Is_Unchecked_Union (Full) then
2748 Set_Is_Unchecked_Union (Base_Type (Priv));
2750 -- Why is atomic not copied here ???
2752 if Referenced (Full) then
2753 Set_Referenced (Priv);
2756 if Priv_Is_Base_Type then
2757 Set_Is_Controlled_Active
2758 (Priv, Is_Controlled_Active (Full_Base));
2759 Set_Finalize_Storage_Only
2760 (Priv, Finalize_Storage_Only (Full_Base));
2761 Set_Has_Controlled_Component
2762 (Priv, Has_Controlled_Component (Full_Base));
2764 Propagate_Concurrent_Flags (Priv, Base_Type (Full));
2767 -- As explained in Freeze_Entity, private types are required to point
2768 -- to the same freeze node as their corresponding full view, if any.
2769 -- But we ought not to overwrite a node already inserted in the tree.
2772 (Serious_Errors_Detected /= 0
2773 or else No (Freeze_Node (Priv))
2774 or else No (Parent (Freeze_Node (Priv)))
2775 or else Freeze_Node (Priv) = Freeze_Node (Full));
2777 Set_Freeze_Node (Priv, Freeze_Node (Full));
2779 -- Propagate Default_Initial_Condition-related attributes from the
2780 -- base type of the full view to the full view and vice versa. This
2781 -- may seem strange, but is necessary depending on which type
2782 -- triggered the generation of the DIC procedure body. As a result,
2783 -- both the full view and its base type carry the same DIC-related
2786 Propagate_DIC_Attributes (Full, From_Typ => Full_Base);
2787 Propagate_DIC_Attributes (Full_Base, From_Typ => Full);
2789 -- Propagate Default_Initial_Condition-related attributes from the
2790 -- full view to the private view.
2792 Propagate_DIC_Attributes (Priv, From_Typ => Full);
2794 -- Propagate invariant-related attributes from the base type of the
2795 -- full view to the full view and vice versa. This may seem strange,
2796 -- but is necessary depending on which type triggered the generation
2797 -- of the invariant procedure body. As a result, both the full view
2798 -- and its base type carry the same invariant-related information.
2800 Propagate_Invariant_Attributes (Full, From_Typ => Full_Base);
2801 Propagate_Invariant_Attributes (Full_Base, From_Typ => Full);
2803 -- Propagate invariant-related attributes from the full view to the
2806 Propagate_Invariant_Attributes (Priv, From_Typ => Full);
2808 if Is_Tagged_Type (Priv)
2809 and then Is_Tagged_Type (Full)
2810 and then not Error_Posted (Full)
2812 if Is_Tagged_Type (Priv) then
2814 -- If the type is tagged, the tag itself must be available on
2815 -- the partial view, for expansion purposes.
2817 Set_First_Entity (Priv, First_Entity (Full));
2819 -- If there are discriminants in the partial view, these remain
2820 -- visible. Otherwise only the tag itself is visible, and there
2821 -- are no nameable components in the partial view.
2823 if No (Last_Entity (Priv)) then
2824 Set_Last_Entity (Priv, First_Entity (Priv));
2828 Set_Has_Discriminants (Priv, Has_Discriminants (Full));
2830 if Has_Discriminants (Full) then
2831 Set_Discriminant_Constraint (Priv,
2832 Discriminant_Constraint (Full));
2835 end Preserve_Full_Attributes;
2837 -----------------------------
2838 -- Swap_Private_Dependents --
2839 -----------------------------
2841 procedure Swap_Private_Dependents (Priv_Deps : Elist_Id) is
2845 Priv_Elmt : Elmt_Id;
2849 Priv_Elmt := First_Elmt (Priv_Deps);
2850 while Present (Priv_Elmt) loop
2851 Priv := Node (Priv_Elmt);
2853 -- Before we do the swap, we verify the presence of the Full_View
2854 -- field, which may be empty due to a swap by a previous call to
2855 -- End_Package_Scope (e.g. from the freezing mechanism).
2857 if Present (Full_View (Priv)) then
2858 if Is_Private_Type (Priv) then
2859 Cunit := Cunit_Entity (Current_Sem_Unit);
2860 Deps := Private_Dependents (Priv);
2867 or else not In_Open_Scopes (Scope (Priv))
2869 Set_Is_Immediately_Visible (Priv, False);
2872 if Is_Visible_Dependent (Priv) then
2873 Preserve_Full_Attributes (Priv, Full_View (Priv));
2874 Replace_Elmt (Priv_Elmt, Full_View (Priv));
2875 Exchange_Declarations (Priv);
2877 -- Recurse for child units, except in generic child units,
2878 -- which unfortunately handle private_dependents separately.
2879 -- Note that the current unit may not have been analyzed,
2880 -- for example a package body, so we cannot rely solely on
2881 -- the Is_Child_Unit flag, but that's only an optimization.
2884 and then (No (Etype (Cunit)) or else Is_Child_Unit (Cunit))
2885 and then not Is_Empty_Elmt_List (Deps)
2886 and then not Inside_A_Generic
2888 Swap_Private_Dependents (Deps);
2893 Next_Elmt (Priv_Elmt);
2895 end Swap_Private_Dependents;
2901 function Type_In_Use (T : Entity_Id) return Boolean is
2903 return Scope (Base_Type (T)) = P
2904 and then (In_Use (T) or else In_Use (Base_Type (T)));
2907 -- Start of processing for Uninstall_Declarations
2910 Id := First_Entity (P);
2911 while Present (Id) and then Id /= First_Private_Entity (P) loop
2912 if Debug_Flag_E then
2913 Write_Str ("unlinking visible entity ");
2914 Write_Int (Int (Id));
2918 -- On exit from the package scope, we must preserve the visibility
2919 -- established by use clauses in the current scope. Two cases:
2921 -- a) If the entity is an operator, it may be a primitive operator of
2922 -- a type for which there is a visible use-type clause.
2924 -- b) For other entities, their use-visibility is determined by a
2925 -- visible use clause for the package itself or a use-all-type clause
2926 -- applied directly to the entity's type. For a generic instance,
2927 -- the instantiation of the formals appears in the visible part,
2928 -- but the formals are private and remain so.
2930 if Ekind (Id) = E_Function
2931 and then Is_Operator_Symbol_Name (Chars (Id))
2932 and then not Is_Hidden (Id)
2933 and then not Error_Posted (Id)
2935 Set_Is_Potentially_Use_Visible (Id,
2937 or else Type_In_Use (Etype (Id))
2938 or else Type_In_Use (Etype (First_Formal (Id)))
2939 or else (Present (Next_Formal (First_Formal (Id)))
2942 (Etype (Next_Formal (First_Formal (Id))))));
2944 if In_Use (P) and then not Is_Hidden (Id) then
2946 -- A child unit of a use-visible package remains use-visible
2947 -- only if it is itself a visible child unit. Otherwise it
2948 -- would remain visible in other contexts where P is use-
2949 -- visible, because once compiled it stays in the entity list
2950 -- of its parent unit.
2952 if Is_Child_Unit (Id) then
2953 Set_Is_Potentially_Use_Visible
2954 (Id, Is_Visible_Lib_Unit (Id));
2956 Set_Is_Potentially_Use_Visible (Id);
2959 -- We need to avoid incorrectly marking enumeration literals as
2960 -- non-visible when a visible use-all-type clause is in effect.
2962 elsif Type_In_Use (Etype (Id))
2963 and then Nkind (Current_Use_Clause (Etype (Id))) =
2965 and then All_Present (Current_Use_Clause (Etype (Id)))
2970 Set_Is_Potentially_Use_Visible (Id, False);
2974 -- Local entities are not immediately visible outside of the package
2976 Set_Is_Immediately_Visible (Id, False);
2978 -- If this is a private type with a full view (for example a local
2979 -- subtype of a private type declared elsewhere), ensure that the
2980 -- full view is also removed from visibility: it may be exposed when
2981 -- swapping views in an instantiation. Similarly, ensure that the
2982 -- use-visibility is properly set on both views.
2984 if Is_Type (Id) and then Present (Full_View (Id)) then
2985 Set_Is_Immediately_Visible (Full_View (Id), False);
2986 Set_Is_Potentially_Use_Visible (Full_View (Id),
2987 Is_Potentially_Use_Visible (Id));
2990 if Is_Tagged_Type (Id) and then Ekind (Id) = E_Record_Type then
2991 Check_Abstract_Overriding (Id);
2992 Check_Conventions (Id);
2995 if Ekind_In (Id, E_Private_Type, E_Limited_Private_Type)
2996 and then No (Full_View (Id))
2997 and then not Is_Generic_Type (Id)
2998 and then not Is_Derived_Type (Id)
3000 Error_Msg_N ("missing full declaration for private type&", Id);
3002 elsif Ekind (Id) = E_Record_Type_With_Private
3003 and then not Is_Generic_Type (Id)
3004 and then No (Full_View (Id))
3006 if Nkind (Parent (Id)) = N_Private_Type_Declaration then
3007 Error_Msg_N ("missing full declaration for private type&", Id);
3010 ("missing full declaration for private extension", Id);
3013 -- Case of constant, check for deferred constant declaration with
3014 -- no full view. Likely just a matter of a missing expression, or
3015 -- accidental use of the keyword constant.
3017 elsif Ekind (Id) = E_Constant
3019 -- OK if constant value present
3021 and then No (Constant_Value (Id))
3023 -- OK if full view present
3025 and then No (Full_View (Id))
3027 -- OK if imported, since that provides the completion
3029 and then not Is_Imported (Id)
3031 -- OK if object declaration replaced by renaming declaration as
3032 -- a result of OK_To_Rename processing (e.g. for concatenation)
3034 and then Nkind (Parent (Id)) /= N_Object_Renaming_Declaration
3036 -- OK if object declaration with the No_Initialization flag set
3038 and then not (Nkind (Parent (Id)) = N_Object_Declaration
3039 and then No_Initialization (Parent (Id)))
3041 -- If no private declaration is present, we assume the user did
3042 -- not intend a deferred constant declaration and the problem
3043 -- is simply that the initializing expression is missing.
3045 if not Has_Private_Declaration (Etype (Id)) then
3047 -- We assume that the user did not intend a deferred constant
3048 -- declaration, and the expression is just missing.
3051 ("constant declaration requires initialization expression",
3054 if Is_Limited_Type (Etype (Id)) then
3056 ("\if variable intended, remove CONSTANT from declaration",
3060 -- Otherwise if a private declaration is present, then we are
3061 -- missing the full declaration for the deferred constant.
3065 ("missing full declaration for deferred constant (RM 7.4)",
3068 if Is_Limited_Type (Etype (Id)) then
3070 ("\if variable intended, remove CONSTANT from declaration",
3079 -- If the specification was installed as the parent of a public child
3080 -- unit, the private declarations were not installed, and there is
3083 if not In_Private_Part (P) then
3086 Set_In_Private_Part (P, False);
3089 -- Make private entities invisible and exchange full and private
3090 -- declarations for private types. Id is now the first private entity
3093 while Present (Id) loop
3094 if Debug_Flag_E then
3095 Write_Str ("unlinking private entity ");
3096 Write_Int (Int (Id));
3100 if Is_Tagged_Type (Id) and then Ekind (Id) = E_Record_Type then
3101 Check_Abstract_Overriding (Id);
3102 Check_Conventions (Id);
3105 Set_Is_Immediately_Visible (Id, False);
3107 if Is_Private_Base_Type (Id) and then Present (Full_View (Id)) then
3108 Full := Full_View (Id);
3110 -- If the partial view is not declared in the visible part of the
3111 -- package (as is the case when it is a type derived from some
3112 -- other private type in the private part of the current package),
3113 -- no exchange takes place.
3116 or else List_Containing (Parent (Id)) /=
3117 Visible_Declarations (Specification (Decl))
3122 -- The entry in the private part points to the full declaration,
3123 -- which is currently visible. Exchange them so only the private
3124 -- type declaration remains accessible, and link private and full
3125 -- declaration in the opposite direction. Before the actual
3126 -- exchange, we copy back attributes of the full view that must
3127 -- be available to the partial view too.
3129 Preserve_Full_Attributes (Id, Full);
3131 Set_Is_Potentially_Use_Visible (Id, In_Use (P));
3133 -- The following test may be redundant, as this is already
3134 -- diagnosed in sem_ch3. ???
3136 if not Is_Definite_Subtype (Full)
3137 and then Is_Definite_Subtype (Id)
3139 Error_Msg_Sloc := Sloc (Parent (Id));
3141 ("full view of& not compatible with declaration#", Full, Id);
3144 -- Swap out the subtypes and derived types of Id that
3145 -- were compiled in this scope, or installed previously
3146 -- by Install_Private_Declarations.
3148 Swap_Private_Dependents (Private_Dependents (Id));
3150 -- Now restore the type itself to its private view
3152 Exchange_Declarations (Id);
3154 -- If we have installed an underlying full view for a type derived
3155 -- from a private type in a child unit, restore the proper views
3156 -- of private and full view. See corresponding code in
3157 -- Install_Private_Declarations.
3159 -- After the exchange, Full denotes the private type in the
3160 -- visible part of the package.
3162 if Is_Private_Base_Type (Full)
3163 and then Present (Full_View (Full))
3164 and then Present (Underlying_Full_View (Full))
3165 and then In_Package_Body (Current_Scope)
3167 Set_Full_View (Full, Underlying_Full_View (Full));
3168 Set_Underlying_Full_View (Full, Empty);
3171 elsif Ekind (Id) = E_Incomplete_Type
3172 and then Comes_From_Source (Id)
3173 and then No (Full_View (Id))
3175 -- Mark Taft amendment types. Verify that there are no primitive
3176 -- operations declared for the type (3.10.1(9)).
3178 Set_Has_Completion_In_Body (Id);
3185 Elmt := First_Elmt (Private_Dependents (Id));
3186 while Present (Elmt) loop
3187 Subp := Node (Elmt);
3189 -- Is_Primitive is tested because there can be cases where
3190 -- nonprimitive subprograms (in nested packages) are added
3191 -- to the Private_Dependents list.
3193 if Is_Overloadable (Subp) and then Is_Primitive (Subp) then
3195 ("type& must be completed in the private part",
3198 -- The result type of an access-to-function type cannot be a
3199 -- Taft-amendment type, unless the version is Ada 2012 or
3200 -- later (see AI05-151).
3202 elsif Ada_Version < Ada_2012
3203 and then Ekind (Subp) = E_Subprogram_Type
3205 if Etype (Subp) = Id
3207 (Is_Class_Wide_Type (Etype (Subp))
3208 and then Etype (Etype (Subp)) = Id)
3211 ("type& must be completed in the private part",
3212 Associated_Node_For_Itype (Subp), Id);
3220 elsif not Is_Child_Unit (Id)
3221 and then (not Is_Private_Type (Id) or else No (Full_View (Id)))
3224 Set_Is_Potentially_Use_Visible (Id, False);
3230 end Uninstall_Declarations;
3232 ------------------------
3233 -- Unit_Requires_Body --
3234 ------------------------
3236 function Unit_Requires_Body
3237 (Pack_Id : Entity_Id;
3238 Do_Abstract_States : Boolean := False) return Boolean
3242 Requires_Body : Boolean := False;
3243 -- Flag set when the unit has at least one construct that requires
3244 -- completion in a body.
3247 -- Imported entity never requires body. Right now, only subprograms can
3248 -- be imported, but perhaps in the future we will allow import of
3251 if Is_Imported (Pack_Id) then
3254 -- Body required if library package with pragma Elaborate_Body
3256 elsif Has_Pragma_Elaborate_Body (Pack_Id) then
3259 -- Body required if subprogram
3261 elsif Is_Subprogram_Or_Generic_Subprogram (Pack_Id) then
3264 -- Treat a block as requiring a body
3266 elsif Ekind (Pack_Id) = E_Block then
3269 elsif Ekind (Pack_Id) = E_Package
3270 and then Nkind (Parent (Pack_Id)) = N_Package_Specification
3271 and then Present (Generic_Parent (Parent (Pack_Id)))
3274 G_P : constant Entity_Id := Generic_Parent (Parent (Pack_Id));
3276 if Has_Pragma_Elaborate_Body (G_P) then
3282 -- Traverse the entity chain of the package and look for constructs that
3283 -- require a completion in a body.
3285 E := First_Entity (Pack_Id);
3286 while Present (E) loop
3288 -- Skip abstract states because their completion depends on several
3289 -- criteria (see below).
3291 if Ekind (E) = E_Abstract_State then
3294 elsif Requires_Completion_In_Body
3295 (E, Pack_Id, Do_Abstract_States)
3297 Requires_Body := True;
3304 -- A [generic] package that defines at least one non-null abstract state
3305 -- requires a completion only when at least one other construct requires
3306 -- a completion in a body (SPARK RM 7.1.4(4) and (5)). This check is not
3307 -- performed if the caller requests this behavior.
3309 if Do_Abstract_States
3310 and then Ekind_In (Pack_Id, E_Generic_Package, E_Package)
3311 and then Has_Non_Null_Abstract_State (Pack_Id)
3312 and then Requires_Body
3317 return Requires_Body;
3318 end Unit_Requires_Body;
3320 -----------------------------
3321 -- Unit_Requires_Body_Info --
3322 -----------------------------
3324 procedure Unit_Requires_Body_Info (Pack_Id : Entity_Id) is
3328 -- An imported entity never requires body. Right now, only subprograms
3329 -- can be imported, but perhaps in the future we will allow import of
3332 if Is_Imported (Pack_Id) then
3335 -- Body required if library package with pragma Elaborate_Body
3337 elsif Has_Pragma_Elaborate_Body (Pack_Id) then
3338 Error_Msg_N ("info: & requires body (Elaborate_Body)?Y?", Pack_Id);
3340 -- Body required if subprogram
3342 elsif Is_Subprogram_Or_Generic_Subprogram (Pack_Id) then
3343 Error_Msg_N ("info: & requires body (subprogram case)?Y?", Pack_Id);
3345 -- Body required if generic parent has Elaborate_Body
3347 elsif Ekind (Pack_Id) = E_Package
3348 and then Nkind (Parent (Pack_Id)) = N_Package_Specification
3349 and then Present (Generic_Parent (Parent (Pack_Id)))
3352 G_P : constant Entity_Id := Generic_Parent (Parent (Pack_Id));
3354 if Has_Pragma_Elaborate_Body (G_P) then
3356 ("info: & requires body (generic parent Elaborate_Body)?Y?",
3361 -- A [generic] package that introduces at least one non-null abstract
3362 -- state requires completion. However, there is a separate rule that
3363 -- requires that such a package have a reason other than this for a
3364 -- body being required (if necessary a pragma Elaborate_Body must be
3365 -- provided). If Ignore_Abstract_State is True, we don't do this check
3366 -- (so we can use Unit_Requires_Body to check for some other reason).
3368 elsif Ekind_In (Pack_Id, E_Generic_Package, E_Package)
3369 and then Present (Abstract_States (Pack_Id))
3370 and then not Is_Null_State
3371 (Node (First_Elmt (Abstract_States (Pack_Id))))
3374 ("info: & requires body (non-null abstract state aspect)?Y?",
3378 -- Otherwise search entity chain for entity requiring completion
3380 E := First_Entity (Pack_Id);
3381 while Present (E) loop
3382 if Requires_Completion_In_Body (E, Pack_Id) then
3383 Error_Msg_Node_2 := E;
3385 ("info: & requires body (& requires completion)?Y?", E, Pack_Id);
3390 end Unit_Requires_Body_Info;