1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2014, 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 Debug; use Debug;
34 with Einfo; use Einfo;
35 with Elists; use Elists;
36 with Errout; use Errout;
37 with Exp_Disp; use Exp_Disp;
38 with Exp_Dist; use Exp_Dist;
39 with Exp_Dbug; use Exp_Dbug;
41 with Lib.Xref; use Lib.Xref;
42 with Namet; use Namet;
43 with Nmake; use Nmake;
44 with Nlists; use Nlists;
46 with Output; use Output;
47 with Restrict; use Restrict;
49 with Sem_Aux; use Sem_Aux;
50 with Sem_Cat; use Sem_Cat;
51 with Sem_Ch3; use Sem_Ch3;
52 with Sem_Ch6; use Sem_Ch6;
53 with Sem_Ch8; use Sem_Ch8;
54 with Sem_Ch10; use Sem_Ch10;
55 with Sem_Ch12; use Sem_Ch12;
56 with Sem_Ch13; use Sem_Ch13;
57 with Sem_Disp; use Sem_Disp;
58 with Sem_Eval; use Sem_Eval;
59 with Sem_Prag; use Sem_Prag;
60 with Sem_Util; use Sem_Util;
61 with Sem_Warn; use Sem_Warn;
62 with Snames; use Snames;
63 with Stand; use Stand;
64 with Sinfo; use Sinfo;
65 with Sinput; use Sinput;
67 with Uintp; use Uintp;
69 package body Sem_Ch7 is
71 -----------------------------------
72 -- Handling private declarations --
73 -----------------------------------
75 -- The principle that each entity has a single defining occurrence clashes
76 -- with the presence of two separate definitions for private types: the
77 -- first is the private type declaration, and the second is the full type
78 -- declaration. It is important that all references to the type point to
79 -- the same defining occurrence, namely the first one. To enforce the two
80 -- separate views of the entity, the corresponding information is swapped
81 -- between the two declarations. Outside of the package, the defining
82 -- occurrence only contains the private declaration information, while in
83 -- the private part and the body of the package the defining occurrence
84 -- contains the full declaration. To simplify the swap, the defining
85 -- occurrence that currently holds the private declaration points to the
86 -- full declaration. During semantic processing the defining occurrence
87 -- also points to a list of private dependents, that is to say access types
88 -- or composite types whose designated types or component types are
89 -- subtypes or derived types of the private type in question. After the
90 -- full declaration has been seen, the private dependents are updated to
91 -- indicate that they have full definitions.
93 -----------------------
94 -- Local Subprograms --
95 -----------------------
97 procedure Analyze_Package_Body_Helper (N : Node_Id);
98 -- Does all the real work of Analyze_Package_Body
100 procedure Check_Anonymous_Access_Types
101 (Spec_Id : Entity_Id;
103 -- If the spec of a package has a limited_with_clause, it may declare
104 -- anonymous access types whose designated type is a limited view, such an
105 -- anonymous access return type for a function. This access type cannot be
106 -- elaborated in the spec itself, but it may need an itype reference if it
107 -- is used within a nested scope. In that case the itype reference is
108 -- created at the beginning of the corresponding package body and inserted
109 -- before other body declarations.
111 procedure Install_Package_Entity (Id : Entity_Id);
112 -- Supporting procedure for Install_{Visible,Private}_Declarations. Places
113 -- one entity on its visibility chain, and recurses on the visible part if
114 -- the entity is an inner package.
116 function Is_Private_Base_Type (E : Entity_Id) return Boolean;
117 -- True for a private type that is not a subtype
119 function Is_Visible_Dependent (Dep : Entity_Id) return Boolean;
120 -- If the private dependent is a private type whose full view is derived
121 -- from the parent type, its full properties are revealed only if we are in
122 -- the immediate scope of the private dependent. Should this predicate be
123 -- tightened further???
125 procedure Declare_Inherited_Private_Subprograms (Id : Entity_Id);
126 -- Called upon entering the private part of a public child package and the
127 -- body of a nested package, to potentially declare certain inherited
128 -- subprograms that were inherited by types in the visible part, but whose
129 -- declaration was deferred because the parent operation was private and
130 -- not visible at that point. These subprograms are located by traversing
131 -- the visible part declarations looking for non-private type extensions
132 -- and then examining each of the primitive operations of such types to
133 -- find those that were inherited but declared with a special internal
134 -- name. Each such operation is now declared as an operation with a normal
135 -- name (using the name of the parent operation) and replaces the previous
136 -- implicit operation in the primitive operations list of the type. If the
137 -- inherited private operation has been overridden, then it's replaced by
138 -- the overriding operation.
140 procedure Unit_Requires_Body_Info (P : Entity_Id);
141 -- Outputs info messages showing why package specification P requires a
142 -- body. Caller has checked that the switch requesting this information
143 -- is set, and that the package does indeed require a body.
145 --------------------------
146 -- Analyze_Package_Body --
147 --------------------------
149 procedure Analyze_Package_Body (N : Node_Id) is
150 Loc : constant Source_Ptr := Sloc (N);
154 Write_Str ("==> package body ");
155 Write_Name (Chars (Defining_Entity (N)));
156 Write_Str (" from ");
157 Write_Location (Loc);
162 -- The real work is split out into the helper, so it can do "return;"
163 -- without skipping the debug output.
165 Analyze_Package_Body_Helper (N);
169 Write_Str ("<== package body ");
170 Write_Name (Chars (Defining_Entity (N)));
171 Write_Str (" from ");
172 Write_Location (Loc);
175 end Analyze_Package_Body;
177 -----------------------------------
178 -- Analyze_Package_Body_Contract --
179 -----------------------------------
181 procedure Analyze_Package_Body_Contract (Body_Id : Entity_Id) is
182 Spec_Id : constant Entity_Id := Spec_Entity (Body_Id);
183 Mode : SPARK_Mode_Type;
187 -- Due to the timing of contract analysis, delayed pragmas may be
188 -- subject to the wrong SPARK_Mode, usually that of the enclosing
189 -- context. To remedy this, restore the original SPARK_Mode of the
190 -- related package body.
192 Save_SPARK_Mode_And_Set (Body_Id, Mode);
194 Prag := Get_Pragma (Body_Id, Pragma_Refined_State);
196 -- The analysis of pragma Refined_State detects whether the spec has
197 -- abstract states available for refinement.
199 if Present (Prag) then
200 Analyze_Refined_State_In_Decl_Part (Prag);
202 -- State refinement is required when the package declaration defines at
203 -- least one abstract state. Null states are not considered. Refinement
204 -- is not envorced when SPARK checks are turned off.
206 elsif SPARK_Mode /= Off
207 and then Requires_State_Refinement (Spec_Id, Body_Id)
209 Error_Msg_N ("package & requires state refinement", Spec_Id);
212 -- Restore the SPARK_Mode of the enclosing context after all delayed
213 -- pragmas have been analyzed.
215 Restore_SPARK_Mode (Mode);
216 end Analyze_Package_Body_Contract;
218 ---------------------------------
219 -- Analyze_Package_Body_Helper --
220 ---------------------------------
222 procedure Analyze_Package_Body_Helper (N : Node_Id) is
226 Last_Spec_Entity : Entity_Id;
230 procedure Install_Composite_Operations (P : Entity_Id);
231 -- Composite types declared in the current scope may depend on types
232 -- that were private at the point of declaration, and whose full view
233 -- is now in scope. Indicate that the corresponding operations on the
234 -- composite type are available.
236 ----------------------------------
237 -- Install_Composite_Operations --
238 ----------------------------------
240 procedure Install_Composite_Operations (P : Entity_Id) is
244 Id := First_Entity (P);
245 while Present (Id) loop
247 and then (Is_Limited_Composite (Id)
248 or else Is_Private_Composite (Id))
249 and then No (Private_Component (Id))
251 Set_Is_Limited_Composite (Id, False);
252 Set_Is_Private_Composite (Id, False);
257 end Install_Composite_Operations;
259 -- Start of processing for Analyze_Package_Body_Helper
262 -- Find corresponding package specification, and establish the current
263 -- scope. The visible defining entity for the package is the defining
264 -- occurrence in the spec. On exit from the package body, all body
265 -- declarations are attached to the defining entity for the body, but
266 -- the later is never used for name resolution. In this fashion there
267 -- is only one visible entity that denotes the package.
269 -- Set Body_Id. Note that this will be reset to point to the generic
270 -- copy later on in the generic case.
272 Body_Id := Defining_Entity (N);
274 -- Body is body of package instantiation. Corresponding spec has already
277 if Present (Corresponding_Spec (N)) then
278 Spec_Id := Corresponding_Spec (N);
279 Pack_Decl := Unit_Declaration_Node (Spec_Id);
282 Spec_Id := Current_Entity_In_Scope (Defining_Entity (N));
284 if Present (Spec_Id) and then Is_Package_Or_Generic_Package (Spec_Id)
286 Pack_Decl := Unit_Declaration_Node (Spec_Id);
288 if Nkind (Pack_Decl) = N_Package_Renaming_Declaration then
289 Error_Msg_N ("cannot supply body for package renaming", N);
292 elsif Present (Corresponding_Body (Pack_Decl)) then
293 Error_Msg_N ("redefinition of package body", N);
298 Error_Msg_N ("missing specification for package body", N);
302 if Is_Package_Or_Generic_Package (Spec_Id)
303 and then (Scope (Spec_Id) = Standard_Standard
304 or else Is_Child_Unit (Spec_Id))
305 and then not Unit_Requires_Body (Spec_Id)
307 if Ada_Version = Ada_83 then
309 ("optional package body (not allowed in Ada 95)??", N);
311 Error_Msg_N ("spec of this package does not allow a body", N);
316 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
317 Style.Check_Identifier (Body_Id, Spec_Id);
319 if Is_Child_Unit (Spec_Id) then
320 if Nkind (Parent (N)) /= N_Compilation_Unit then
322 ("body of child unit& cannot be an inner package", N, Spec_Id);
325 Set_Is_Child_Unit (Body_Id);
328 -- Generic package case
330 if Ekind (Spec_Id) = E_Generic_Package then
332 -- Disable expansion and perform semantic analysis on copy. The
333 -- unannotated body will be used in all instantiations.
335 Body_Id := Defining_Entity (N);
336 Set_Ekind (Body_Id, E_Package_Body);
337 Set_Scope (Body_Id, Scope (Spec_Id));
338 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
339 Set_Body_Entity (Spec_Id, Body_Id);
340 Set_Spec_Entity (Body_Id, Spec_Id);
342 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
345 -- Once the contents of the generic copy and the template are
346 -- swapped, do the same for their respective aspect specifications.
348 Exchange_Aspects (N, New_N);
350 -- Update Body_Id to point to the copied node for the remainder of
353 Body_Id := Defining_Entity (N);
357 -- The Body_Id is that of the copied node in the generic case, the
358 -- current node otherwise. Note that N was rewritten above, so we must
359 -- be sure to get the latest Body_Id value.
361 Set_Ekind (Body_Id, E_Package_Body);
362 Set_Body_Entity (Spec_Id, Body_Id);
363 Set_Spec_Entity (Body_Id, Spec_Id);
364 Set_Contract (Body_Id, Make_Contract (Sloc (Body_Id)));
366 -- Defining name for the package body is not a visible entity: Only the
367 -- defining name for the declaration is visible.
369 Set_Etype (Body_Id, Standard_Void_Type);
370 Set_Scope (Body_Id, Scope (Spec_Id));
371 Set_Corresponding_Spec (N, Spec_Id);
372 Set_Corresponding_Body (Pack_Decl, Body_Id);
374 -- The body entity is not used for semantics or code generation, but
375 -- it is attached to the entity list of the enclosing scope to simplify
376 -- the listing of back-annotations for the types it main contain.
378 if Scope (Spec_Id) /= Standard_Standard then
379 Append_Entity (Body_Id, Scope (Spec_Id));
382 -- Indicate that we are currently compiling the body of the package
384 Set_In_Package_Body (Spec_Id);
385 Set_Has_Completion (Spec_Id);
386 Last_Spec_Entity := Last_Entity (Spec_Id);
388 if Has_Aspects (N) then
389 Analyze_Aspect_Specifications (N, Body_Id);
392 Push_Scope (Spec_Id);
394 -- Set SPARK_Mode only for non-generic package
396 if Ekind (Spec_Id) = E_Package then
398 -- Set SPARK_Mode from context
400 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
401 Set_SPARK_Pragma_Inherited (Body_Id, True);
403 -- Set elaboration code SPARK mode the same for now
405 Set_SPARK_Aux_Pragma (Body_Id, SPARK_Pragma (Body_Id));
406 Set_SPARK_Aux_Pragma_Inherited (Body_Id, True);
409 Set_Categorization_From_Pragmas (N);
411 Install_Visible_Declarations (Spec_Id);
412 Install_Private_Declarations (Spec_Id);
413 Install_Private_With_Clauses (Spec_Id);
414 Install_Composite_Operations (Spec_Id);
416 Check_Anonymous_Access_Types (Spec_Id, N);
418 if Ekind (Spec_Id) = E_Generic_Package then
419 Set_Use (Generic_Formal_Declarations (Pack_Decl));
422 Set_Use (Visible_Declarations (Specification (Pack_Decl)));
423 Set_Use (Private_Declarations (Specification (Pack_Decl)));
425 -- This is a nested package, so it may be necessary to declare certain
426 -- inherited subprograms that are not yet visible because the parent
427 -- type's subprograms are now visible.
429 if Ekind (Scope (Spec_Id)) = E_Package
430 and then Scope (Spec_Id) /= Standard_Standard
432 Declare_Inherited_Private_Subprograms (Spec_Id);
435 if Present (Declarations (N)) then
436 Analyze_Declarations (Declarations (N));
437 Inspect_Deferred_Constant_Completion (Declarations (N));
440 -- After declarations have been analyzed, the body has been set to have
441 -- the final value of SPARK_Mode. Check that the SPARK_Mode for the body
442 -- is consistent with the SPARK_Mode for the spec.
444 if Present (SPARK_Pragma (Body_Id)) then
445 if Present (SPARK_Aux_Pragma (Spec_Id)) then
446 if Get_SPARK_Mode_From_Pragma (SPARK_Aux_Pragma (Spec_Id)) = Off
448 Get_SPARK_Mode_From_Pragma (SPARK_Pragma (Body_Id)) = On
450 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
451 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
452 Error_Msg_Sloc := Sloc (SPARK_Aux_Pragma (Spec_Id));
454 ("\value Off was set for SPARK_Mode on & #", N, Spec_Id);
458 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
459 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
460 Error_Msg_Sloc := Sloc (Spec_Id);
462 ("\no value was set for SPARK_Mode on & #", N, Spec_Id);
466 -- Analyze_Declarations has caused freezing of all types. Now generate
467 -- bodies for RACW primitives and stream attributes, if any.
469 if Ekind (Spec_Id) = E_Package and then Has_RACW (Spec_Id) then
471 -- Attach subprogram bodies to support RACWs declared in spec
473 Append_RACW_Bodies (Declarations (N), Spec_Id);
474 Analyze_List (Declarations (N));
477 HSS := Handled_Statement_Sequence (N);
479 if Present (HSS) then
480 Process_End_Label (HSS, 't', Spec_Id);
483 -- Check that elaboration code in a preelaborable package body is
484 -- empty other than null statements and labels (RM 10.2.1(6)).
486 Validate_Null_Statement_Sequence (N);
489 Validate_Categorization_Dependency (N, Spec_Id);
490 Check_Completion (Body_Id);
492 -- Generate start of body reference. Note that we do this fairly late,
493 -- because the call will use In_Extended_Main_Source_Unit as a check,
494 -- and we want to make sure that Corresponding_Stub links are set
496 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
498 -- For a generic package, collect global references and mark them on
499 -- the original body so that they are not resolved again at the point
502 if Ekind (Spec_Id) /= E_Package then
503 Save_Global_References (Original_Node (N));
507 -- The entities of the package body have so far been chained onto the
508 -- declaration chain for the spec. That's been fine while we were in the
509 -- body, since we wanted them to be visible, but now that we are leaving
510 -- the package body, they are no longer visible, so we remove them from
511 -- the entity chain of the package spec entity, and copy them to the
512 -- entity chain of the package body entity, where they will never again
515 if Present (Last_Spec_Entity) then
516 Set_First_Entity (Body_Id, Next_Entity (Last_Spec_Entity));
517 Set_Next_Entity (Last_Spec_Entity, Empty);
518 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
519 Set_Last_Entity (Spec_Id, Last_Spec_Entity);
522 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
523 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
524 Set_First_Entity (Spec_Id, Empty);
525 Set_Last_Entity (Spec_Id, Empty);
528 End_Package_Scope (Spec_Id);
530 -- All entities declared in body are not visible
536 E := First_Entity (Body_Id);
537 while Present (E) loop
538 Set_Is_Immediately_Visible (E, False);
539 Set_Is_Potentially_Use_Visible (E, False);
542 -- Child units may appear on the entity list (e.g. if they appear
543 -- in the context of a subunit) but they are not body entities.
545 if not Is_Child_Unit (E) then
546 Set_Is_Package_Body_Entity (E);
553 Check_References (Body_Id);
555 -- For a generic unit, check that the formal parameters are referenced,
556 -- and that local variables are used, as for regular packages.
558 if Ekind (Spec_Id) = E_Generic_Package then
559 Check_References (Spec_Id);
562 -- The processing so far has made all entities of the package body
563 -- public (i.e. externally visible to the linker). This is in general
564 -- necessary, since inlined or generic bodies, for which code is
565 -- generated in other units, may need to see these entities. The
566 -- following loop runs backwards from the end of the entities of the
567 -- package body making these entities invisible until we reach a
568 -- referencer, i.e. a declaration that could reference a previous
569 -- declaration, a generic body or an inlined body, or a stub (which may
570 -- contain either of these). This is of course an approximation, but it
571 -- is conservative and definitely correct.
573 -- We only do this at the outer (library) level non-generic packages.
574 -- The reason is simply to cut down on the number of global symbols
575 -- generated, which has a double effect: (1) to make the compilation
576 -- process more efficient and (2) to give the code generator more
577 -- freedom to optimize within each unit, especially subprograms.
579 if (Scope (Spec_Id) = Standard_Standard or else Is_Child_Unit (Spec_Id))
580 and then not Is_Generic_Unit (Spec_Id)
581 and then Present (Declarations (N))
583 Make_Non_Public_Where_Possible : declare
585 function Has_Referencer
587 Outer : Boolean) return Boolean;
588 -- Traverse given list of declarations in reverse order. Return
589 -- True if a referencer is present. Return False if none is found.
591 -- The Outer parameter is True for the outer level call and False
592 -- for inner level calls for nested packages. If Outer is True,
593 -- then any entities up to the point of hitting a referencer get
594 -- their Is_Public flag cleared, so that the entities will be
595 -- treated as static entities in the C sense, and need not have
596 -- fully qualified names. Furthermore, if the referencer is an
597 -- inlined subprogram that doesn't reference other subprograms,
598 -- we keep clearing the Is_Public flag on subprograms. For inner
599 -- levels, we need all names to be fully qualified to deal with
600 -- the same name appearing in parallel packages (right now this
601 -- is tied to their being external).
607 function Has_Referencer
609 Outer : Boolean) return Boolean
611 Has_Referencer_Except_For_Subprograms : Boolean := False;
618 function Check_Subprogram_Ref (N : Node_Id)
619 return Traverse_Result;
620 -- Look for references to subprograms
622 --------------------------
623 -- Check_Subprogram_Ref --
624 --------------------------
626 function Check_Subprogram_Ref (N : Node_Id)
627 return Traverse_Result
632 -- Check name of procedure or function calls
634 if Nkind (N) in N_Subprogram_Call
635 and then Is_Entity_Name (Name (N))
640 -- Check prefix of attribute references
642 if Nkind (N) = N_Attribute_Reference
643 and then Is_Entity_Name (Prefix (N))
644 and then Present (Entity (Prefix (N)))
645 and then Ekind (Entity (Prefix (N))) in Subprogram_Kind
650 -- Check value of constants
652 if Nkind (N) = N_Identifier
653 and then Present (Entity (N))
654 and then Ekind (Entity (N)) = E_Constant
656 V := Constant_Value (Entity (N));
659 and then not Compile_Time_Known_Value_Or_Aggr (V)
666 end Check_Subprogram_Ref;
668 function Check_Subprogram_Refs is
669 new Traverse_Func (Check_Subprogram_Ref);
671 -- Start of processing for Has_Referencer
679 while Present (D) loop
682 if K in N_Body_Stub then
685 -- Processing for subprogram bodies
687 elsif K = N_Subprogram_Body then
688 if Acts_As_Spec (D) then
689 E := Defining_Entity (D);
691 -- An inlined body acts as a referencer. Note also
692 -- that we never reset Is_Public for an inlined
693 -- subprogram. Gigi requires Is_Public to be set.
695 -- Note that we test Has_Pragma_Inline here rather
696 -- than Is_Inlined. We are compiling this for a
697 -- client, and it is the client who will decide if
698 -- actual inlining should occur, so we need to assume
699 -- that the procedure could be inlined for the purpose
700 -- of accessing global entities.
702 if Has_Pragma_Inline (E) then
703 if Outer and then Check_Subprogram_Refs (D) = OK
705 Has_Referencer_Except_For_Subprograms := True;
710 Set_Is_Public (E, False);
714 E := Corresponding_Spec (D);
718 -- A generic subprogram body acts as a referencer
720 if Is_Generic_Unit (E) then
724 if Has_Pragma_Inline (E) or else Is_Inlined (E) then
725 if Outer and then Check_Subprogram_Refs (D) = OK
727 Has_Referencer_Except_For_Subprograms := True;
735 -- Processing for package bodies
737 elsif K = N_Package_Body
738 and then Present (Corresponding_Spec (D))
740 E := Corresponding_Spec (D);
742 -- Generic package body is a referencer. It would seem
743 -- that we only have to consider generics that can be
744 -- exported, i.e. where the corresponding spec is the
745 -- spec of the current package, but because of nested
746 -- instantiations, a fully private generic body may
747 -- export other private body entities. Furthermore,
748 -- regardless of whether there was a previous inlined
749 -- subprogram, (an instantiation of) the generic package
750 -- may reference any entity declared before it.
752 if Is_Generic_Unit (E) then
755 -- For non-generic package body, recurse into body unless
756 -- this is an instance, we ignore instances since they
757 -- cannot have references that affect outer entities.
759 elsif not Is_Generic_Instance (E)
760 and then not Has_Referencer_Except_For_Subprograms
763 (Declarations (D), Outer => False)
769 -- Processing for package specs, recurse into declarations.
770 -- Again we skip this for the case of generic instances.
772 elsif K = N_Package_Declaration
773 and then not Has_Referencer_Except_For_Subprograms
775 S := Specification (D);
777 if not Is_Generic_Unit (Defining_Entity (S)) then
779 (Private_Declarations (S), Outer => False)
783 (Visible_Declarations (S), Outer => False)
789 -- Objects and exceptions need not be public if we have not
790 -- encountered a referencer so far. We only reset the flag
791 -- for outer level entities that are not imported/exported,
792 -- and which have no interface name.
794 elsif Nkind_In (K, N_Object_Declaration,
795 N_Exception_Declaration,
796 N_Subprogram_Declaration)
798 E := Defining_Entity (D);
801 and then (not Has_Referencer_Except_For_Subprograms
802 or else K = N_Subprogram_Declaration)
803 and then not Is_Imported (E)
804 and then not Is_Exported (E)
805 and then No (Interface_Name (E))
807 Set_Is_Public (E, False);
814 return Has_Referencer_Except_For_Subprograms;
817 -- Start of processing for Make_Non_Public_Where_Possible
822 pragma Warnings (Off, Discard);
825 Discard := Has_Referencer (Declarations (N), Outer => True);
827 end Make_Non_Public_Where_Possible;
830 -- If expander is not active, then here is where we turn off the
831 -- In_Package_Body flag, otherwise it is turned off at the end of the
832 -- corresponding expansion routine. If this is an instance body, we need
833 -- to qualify names of local entities, because the body may have been
834 -- compiled as a preliminary to another instantiation.
836 if not Expander_Active then
837 Set_In_Package_Body (Spec_Id, False);
839 if Is_Generic_Instance (Spec_Id)
840 and then Operating_Mode = Generate_Code
842 Qualify_Entity_Names (N);
845 end Analyze_Package_Body_Helper;
847 ------------------------------
848 -- Analyze_Package_Contract --
849 ------------------------------
851 procedure Analyze_Package_Contract (Pack_Id : Entity_Id) is
852 Mode : SPARK_Mode_Type;
856 -- Due to the timing of contract analysis, delayed pragmas may be
857 -- subject to the wrong SPARK_Mode, usually that of the enclosing
858 -- context. To remedy this, restore the original SPARK_Mode of the
861 Save_SPARK_Mode_And_Set (Pack_Id, Mode);
863 -- Analyze the initialization related pragmas. Initializes must come
864 -- before Initial_Condition due to item dependencies.
866 Prag := Get_Pragma (Pack_Id, Pragma_Initializes);
868 if Present (Prag) then
869 Analyze_Initializes_In_Decl_Part (Prag);
872 Prag := Get_Pragma (Pack_Id, Pragma_Initial_Condition);
874 if Present (Prag) then
875 Analyze_Initial_Condition_In_Decl_Part (Prag);
878 -- Check whether the lack of indicator Part_Of agrees with the placement
879 -- of the package instantiation with respect to the state space.
881 if Is_Generic_Instance (Pack_Id) then
882 Prag := Get_Pragma (Pack_Id, Pragma_Part_Of);
885 Check_Missing_Part_Of (Pack_Id);
889 -- Restore the SPARK_Mode of the enclosing context after all delayed
890 -- pragmas have been analyzed.
892 Restore_SPARK_Mode (Mode);
893 end Analyze_Package_Contract;
895 ---------------------------------
896 -- Analyze_Package_Declaration --
897 ---------------------------------
899 procedure Analyze_Package_Declaration (N : Node_Id) is
900 Id : constant Node_Id := Defining_Entity (N);
903 -- True when in the context of a declared pure library unit
905 Body_Required : Boolean;
906 -- True when this package declaration requires a corresponding body
909 -- True when this package declaration is not a nested declaration
913 Write_Str ("==> package spec ");
914 Write_Name (Chars (Id));
915 Write_Str (" from ");
916 Write_Location (Sloc (N));
921 Generate_Definition (Id);
923 Set_Ekind (Id, E_Package);
924 Set_Etype (Id, Standard_Void_Type);
925 Set_Contract (Id, Make_Contract (Sloc (Id)));
927 -- Set SPARK_Mode from context only for non-generic package
929 if Ekind (Id) = E_Package then
930 Set_SPARK_Pragma (Id, SPARK_Mode_Pragma);
931 Set_SPARK_Aux_Pragma (Id, SPARK_Mode_Pragma);
932 Set_SPARK_Pragma_Inherited (Id, True);
933 Set_SPARK_Aux_Pragma_Inherited (Id, True);
936 -- Analyze aspect specifications immediately, since we need to recognize
937 -- things like Pure early enough to diagnose violations during analysis.
939 if Has_Aspects (N) then
940 Analyze_Aspect_Specifications (N, Id);
943 -- Ada 2005 (AI-217): Check if the package has been illegally named
944 -- in a limited-with clause of its own context. In this case the error
945 -- has been previously notified by Analyze_Context.
947 -- limited with Pkg; -- ERROR
948 -- package Pkg is ...
950 if From_Limited_With (Id) then
956 PF := Is_Pure (Enclosing_Lib_Unit_Entity);
957 Set_Is_Pure (Id, PF);
959 Set_Categorization_From_Pragmas (N);
961 Analyze (Specification (N));
962 Validate_Categorization_Dependency (N, Id);
964 Body_Required := Unit_Requires_Body (Id);
966 -- When this spec does not require an explicit body, we know that there
967 -- are no entities requiring completion in the language sense; we call
968 -- Check_Completion here only to ensure that any nested package
969 -- declaration that requires an implicit body gets one. (In the case
970 -- where a body is required, Check_Completion is called at the end of
971 -- the body's declarative part.)
973 if not Body_Required then
977 Comp_Unit := Nkind (Parent (N)) = N_Compilation_Unit;
980 -- Set Body_Required indication on the compilation unit node, and
981 -- determine whether elaboration warnings may be meaningful on it.
983 Set_Body_Required (Parent (N), Body_Required);
985 if not Body_Required then
986 Set_Suppress_Elaboration_Warnings (Id);
991 End_Package_Scope (Id);
993 -- For the declaration of a library unit that is a remote types package,
994 -- check legality rules regarding availability of stream attributes for
995 -- types that contain non-remote access values. This subprogram performs
996 -- visibility tests that rely on the fact that we have exited the scope
1000 Validate_RT_RAT_Component (N);
1003 if Debug_Flag_C then
1005 Write_Str ("<== package spec ");
1006 Write_Name (Chars (Id));
1007 Write_Str (" from ");
1008 Write_Location (Sloc (N));
1011 end Analyze_Package_Declaration;
1013 -----------------------------------
1014 -- Analyze_Package_Specification --
1015 -----------------------------------
1017 -- Note that this code is shared for the analysis of generic package specs
1018 -- (see Sem_Ch12.Analyze_Generic_Package_Declaration for details).
1020 procedure Analyze_Package_Specification (N : Node_Id) is
1021 Id : constant Entity_Id := Defining_Entity (N);
1022 Orig_Decl : constant Node_Id := Original_Node (Parent (N));
1023 Vis_Decls : constant List_Id := Visible_Declarations (N);
1024 Priv_Decls : constant List_Id := Private_Declarations (N);
1027 Public_Child : Boolean;
1029 Private_With_Clauses_Installed : Boolean := False;
1030 -- In Ada 2005, private with_clauses are visible in the private part
1031 -- of a nested package, even if it appears in the public part of the
1032 -- enclosing package. This requires a separate step to install these
1033 -- private_with_clauses, and remove them at the end of the nested
1036 procedure Check_One_Tagged_Type_Or_Extension_At_Most;
1037 -- Issue an error in SPARK mode if a package specification contains
1038 -- more than one tagged type or type extension.
1040 procedure Clear_Constants (Id : Entity_Id; FE : Entity_Id);
1041 -- Clears constant indications (Never_Set_In_Source, Constant_Value, and
1042 -- Is_True_Constant) on all variables that are entities of Id, and on
1043 -- the chain whose first element is FE. A recursive call is made for all
1044 -- packages and generic packages.
1046 procedure Generate_Parent_References;
1047 -- For a child unit, generate references to parent units, for
1048 -- GPS navigation purposes.
1050 function Is_Public_Child (Child, Unit : Entity_Id) return Boolean;
1051 -- Child and Unit are entities of compilation units. True if Child
1052 -- is a public child of Parent as defined in 10.1.1
1054 procedure Inspect_Unchecked_Union_Completion (Decls : List_Id);
1055 -- Reject completion of an incomplete or private type declarations
1056 -- having a known discriminant part by an unchecked union.
1058 procedure Install_Parent_Private_Declarations (Inst_Id : Entity_Id);
1059 -- Given the package entity of a generic package instantiation or
1060 -- formal package whose corresponding generic is a child unit, installs
1061 -- the private declarations of each of the child unit's parents.
1062 -- This has to be done at the point of entering the instance package's
1063 -- private part rather than being done in Sem_Ch12.Install_Parent
1064 -- (which is where the parents' visible declarations are installed).
1066 ------------------------------------------------
1067 -- Check_One_Tagged_Type_Or_Extension_At_Most --
1068 ------------------------------------------------
1070 procedure Check_One_Tagged_Type_Or_Extension_At_Most is
1073 procedure Check_Decls (Decls : List_Id);
1074 -- Check that either Previous is Empty and Decls does not contain
1075 -- more than one tagged type or type extension, or Previous is
1076 -- already set and Decls contains no tagged type or type extension.
1082 procedure Check_Decls (Decls : List_Id) is
1086 Decl := First (Decls);
1087 while Present (Decl) loop
1088 if Nkind (Decl) = N_Full_Type_Declaration
1089 and then Is_Tagged_Type (Defining_Identifier (Decl))
1091 if No (Previous) then
1095 Error_Msg_Sloc := Sloc (Previous);
1096 Check_SPARK_Restriction
1097 ("at most one tagged type or type extension allowed",
1098 "\\ previous declaration#",
1107 -- Start of processing for Check_One_Tagged_Type_Or_Extension_At_Most
1111 Check_Decls (Vis_Decls);
1113 if Present (Priv_Decls) then
1114 Check_Decls (Priv_Decls);
1116 end Check_One_Tagged_Type_Or_Extension_At_Most;
1118 ---------------------
1119 -- Clear_Constants --
1120 ---------------------
1122 procedure Clear_Constants (Id : Entity_Id; FE : Entity_Id) is
1126 -- Ignore package renamings, not interesting and they can cause self
1127 -- referential loops in the code below.
1129 if Nkind (Parent (Id)) = N_Package_Renaming_Declaration then
1133 -- Note: in the loop below, the check for Next_Entity pointing back
1134 -- to the package entity may seem odd, but it is needed, because a
1135 -- package can contain a renaming declaration to itself, and such
1136 -- renamings are generated automatically within package instances.
1139 while Present (E) and then E /= Id loop
1140 if Is_Assignable (E) then
1141 Set_Never_Set_In_Source (E, False);
1142 Set_Is_True_Constant (E, False);
1143 Set_Current_Value (E, Empty);
1144 Set_Is_Known_Null (E, False);
1145 Set_Last_Assignment (E, Empty);
1147 if not Can_Never_Be_Null (E) then
1148 Set_Is_Known_Non_Null (E, False);
1151 elsif Is_Package_Or_Generic_Package (E) then
1152 Clear_Constants (E, First_Entity (E));
1153 Clear_Constants (E, First_Private_Entity (E));
1158 end Clear_Constants;
1160 --------------------------------
1161 -- Generate_Parent_References --
1162 --------------------------------
1164 procedure Generate_Parent_References is
1165 Decl : constant Node_Id := Parent (N);
1168 if Id = Cunit_Entity (Main_Unit)
1169 or else Parent (Decl) = Library_Unit (Cunit (Main_Unit))
1171 Generate_Reference (Id, Scope (Id), 'k', False);
1173 elsif not Nkind_In (Unit (Cunit (Main_Unit)), N_Subprogram_Body,
1176 -- If current unit is an ancestor of main unit, generate a
1177 -- reference to its own parent.
1181 Main_Spec : Node_Id := Unit (Cunit (Main_Unit));
1184 if Nkind (Main_Spec) = N_Package_Body then
1185 Main_Spec := Unit (Library_Unit (Cunit (Main_Unit)));
1188 U := Parent_Spec (Main_Spec);
1189 while Present (U) loop
1190 if U = Parent (Decl) then
1191 Generate_Reference (Id, Scope (Id), 'k', False);
1194 elsif Nkind (Unit (U)) = N_Package_Body then
1198 U := Parent_Spec (Unit (U));
1203 end Generate_Parent_References;
1205 ---------------------
1206 -- Is_Public_Child --
1207 ---------------------
1209 function Is_Public_Child (Child, Unit : Entity_Id) return Boolean is
1211 if not Is_Private_Descendant (Child) then
1214 if Child = Unit then
1215 return not Private_Present (
1216 Parent (Unit_Declaration_Node (Child)));
1218 return Is_Public_Child (Scope (Child), Unit);
1221 end Is_Public_Child;
1223 ----------------------------------------
1224 -- Inspect_Unchecked_Union_Completion --
1225 ----------------------------------------
1227 procedure Inspect_Unchecked_Union_Completion (Decls : List_Id) is
1231 Decl := First (Decls);
1232 while Present (Decl) loop
1234 -- We are looking at an incomplete or private type declaration
1235 -- with a known_discriminant_part whose full view is an
1238 if Nkind_In (Decl, N_Incomplete_Type_Declaration,
1239 N_Private_Type_Declaration)
1240 and then Has_Discriminants (Defining_Identifier (Decl))
1241 and then Present (Full_View (Defining_Identifier (Decl)))
1243 Is_Unchecked_Union (Full_View (Defining_Identifier (Decl)))
1246 ("completion of discriminated partial view "
1247 & "cannot be an unchecked union",
1248 Full_View (Defining_Identifier (Decl)));
1253 end Inspect_Unchecked_Union_Completion;
1255 -----------------------------------------
1256 -- Install_Parent_Private_Declarations --
1257 -----------------------------------------
1259 procedure Install_Parent_Private_Declarations (Inst_Id : Entity_Id) is
1260 Inst_Par : Entity_Id;
1261 Gen_Par : Entity_Id;
1262 Inst_Node : Node_Id;
1265 Inst_Par := Inst_Id;
1268 Generic_Parent (Specification (Unit_Declaration_Node (Inst_Par)));
1269 while Present (Gen_Par) and then Is_Child_Unit (Gen_Par) loop
1270 Inst_Node := Get_Package_Instantiation_Node (Inst_Par);
1272 if Nkind_In (Inst_Node, N_Package_Instantiation,
1273 N_Formal_Package_Declaration)
1274 and then Nkind (Name (Inst_Node)) = N_Expanded_Name
1276 Inst_Par := Entity (Prefix (Name (Inst_Node)));
1278 if Present (Renamed_Entity (Inst_Par)) then
1279 Inst_Par := Renamed_Entity (Inst_Par);
1284 (Specification (Unit_Declaration_Node (Inst_Par)));
1286 -- Install the private declarations and private use clauses
1287 -- of a parent instance of the child instance, unless the
1288 -- parent instance private declarations have already been
1289 -- installed earlier in Analyze_Package_Specification, which
1290 -- happens when a generic child is instantiated, and the
1291 -- instance is a child of the parent instance.
1293 -- Installing the use clauses of the parent instance twice
1294 -- is both unnecessary and wrong, because it would cause the
1295 -- clauses to be chained to themselves in the use clauses
1296 -- list of the scope stack entry. That in turn would cause
1297 -- an endless loop from End_Use_Clauses upon scope exit.
1299 -- The parent is now fully visible. It may be a hidden open
1300 -- scope if we are currently compiling some child instance
1301 -- declared within it, but while the current instance is being
1302 -- compiled the parent is immediately visible. In particular
1303 -- its entities must remain visible if a stack save/restore
1304 -- takes place through a call to Rtsfind.
1306 if Present (Gen_Par) then
1307 if not In_Private_Part (Inst_Par) then
1308 Install_Private_Declarations (Inst_Par);
1309 Set_Use (Private_Declarations
1311 (Unit_Declaration_Node (Inst_Par))));
1312 Set_Is_Hidden_Open_Scope (Inst_Par, False);
1315 -- If we've reached the end of the generic instance parents,
1316 -- then finish off by looping through the nongeneric parents
1317 -- and installing their private declarations.
1319 -- If one of the non-generic parents is itself on the scope
1320 -- stack, do not install its private declarations: they are
1321 -- installed in due time when the private part of that parent
1322 -- is analyzed. This is delicate ???
1325 while Present (Inst_Par)
1326 and then Inst_Par /= Standard_Standard
1327 and then (not In_Open_Scopes (Inst_Par)
1328 or else not In_Private_Part (Inst_Par))
1330 Install_Private_Declarations (Inst_Par);
1331 Set_Use (Private_Declarations
1333 (Unit_Declaration_Node (Inst_Par))));
1334 Inst_Par := Scope (Inst_Par);
1344 end Install_Parent_Private_Declarations;
1346 -- Start of processing for Analyze_Package_Specification
1349 if Present (Vis_Decls) then
1350 Analyze_Declarations (Vis_Decls);
1353 -- Verify that incomplete types have received full declarations and
1354 -- also build invariant procedures for any types with invariants.
1356 E := First_Entity (Id);
1357 while Present (E) loop
1359 -- Check on incomplete types
1361 -- AI05-0213: A formal incomplete type has no completion
1363 if Ekind (E) = E_Incomplete_Type
1364 and then No (Full_View (E))
1365 and then not Is_Generic_Type (E)
1367 Error_Msg_N ("no declaration in visible part for incomplete}", E);
1370 -- Build invariant procedures
1372 if Is_Type (E) and then Has_Invariants (E) then
1373 Build_Invariant_Procedure (E, N);
1379 if Is_Remote_Call_Interface (Id)
1380 and then Nkind (Parent (Parent (N))) = N_Compilation_Unit
1382 Validate_RCI_Declarations (Id);
1385 -- Save global references in the visible declarations, before installing
1386 -- private declarations of parent unit if there is one, because the
1387 -- privacy status of types defined in the parent will change. This is
1388 -- only relevant for generic child units, but is done in all cases for
1391 if Ekind (Id) = E_Generic_Package
1392 and then Nkind (Orig_Decl) = N_Generic_Package_Declaration
1395 Orig_Spec : constant Node_Id := Specification (Orig_Decl);
1396 Save_Priv : constant List_Id := Private_Declarations (Orig_Spec);
1398 Set_Private_Declarations (Orig_Spec, Empty_List);
1399 Save_Global_References (Orig_Decl);
1400 Set_Private_Declarations (Orig_Spec, Save_Priv);
1404 -- If package is a public child unit, then make the private declarations
1405 -- of the parent visible.
1407 Public_Child := False;
1411 Pack_Decl : Node_Id;
1416 Par_Spec := Parent_Spec (Parent (N));
1418 -- If the package is formal package of an enclosing generic, it is
1419 -- transformed into a local generic declaration, and compiled to make
1420 -- its spec available. We need to retrieve the original generic to
1421 -- determine whether it is a child unit, and install its parents.
1425 Nkind (Original_Node (Parent (N))) = N_Formal_Package_Declaration
1427 Par := Entity (Name (Original_Node (Parent (N))));
1428 Par_Spec := Parent_Spec (Unit_Declaration_Node (Par));
1431 if Present (Par_Spec) then
1432 Generate_Parent_References;
1434 while Scope (Par) /= Standard_Standard
1435 and then Is_Public_Child (Id, Par)
1436 and then In_Open_Scopes (Par)
1438 Public_Child := True;
1440 Install_Private_Declarations (Par);
1441 Install_Private_With_Clauses (Par);
1442 Pack_Decl := Unit_Declaration_Node (Par);
1443 Set_Use (Private_Declarations (Specification (Pack_Decl)));
1448 if Is_Compilation_Unit (Id) then
1449 Install_Private_With_Clauses (Id);
1452 -- The current compilation unit may include private with_clauses,
1453 -- which are visible in the private part of the current nested
1454 -- package, and have to be installed now. This is not done for
1455 -- nested instantiations, where the private with_clauses of the
1456 -- enclosing unit have no effect once the instantiation info is
1457 -- established and we start analyzing the package declaration.
1460 Comp_Unit : constant Entity_Id := Cunit_Entity (Current_Sem_Unit);
1462 if Is_Package_Or_Generic_Package (Comp_Unit)
1463 and then not In_Private_Part (Comp_Unit)
1464 and then not In_Instance
1466 Install_Private_With_Clauses (Comp_Unit);
1467 Private_With_Clauses_Installed := True;
1472 -- If this is a package associated with a generic instance or formal
1473 -- package, then the private declarations of each of the generic's
1474 -- parents must be installed at this point.
1476 if Is_Generic_Instance (Id) then
1477 Install_Parent_Private_Declarations (Id);
1480 -- Analyze private part if present. The flag In_Private_Part is reset
1481 -- in End_Package_Scope.
1483 L := Last_Entity (Id);
1485 if Present (Priv_Decls) then
1486 Set_In_Private_Part (Id);
1488 -- Upon entering a public child's private part, it may be necessary
1489 -- to declare subprograms that were derived in the package's visible
1490 -- part but not yet made visible.
1492 if Public_Child then
1493 Declare_Inherited_Private_Subprograms (Id);
1496 Analyze_Declarations (Priv_Decls);
1498 -- Check the private declarations for incomplete deferred constants
1500 Inspect_Deferred_Constant_Completion (Priv_Decls);
1502 -- The first private entity is the immediate follower of the last
1503 -- visible entity, if there was one.
1506 Set_First_Private_Entity (Id, Next_Entity (L));
1508 Set_First_Private_Entity (Id, First_Entity (Id));
1511 -- There may be inherited private subprograms that need to be declared,
1512 -- even in the absence of an explicit private part. If there are any
1513 -- public declarations in the package and the package is a public child
1514 -- unit, then an implicit private part is assumed.
1516 elsif Present (L) and then Public_Child then
1517 Set_In_Private_Part (Id);
1518 Declare_Inherited_Private_Subprograms (Id);
1519 Set_First_Private_Entity (Id, Next_Entity (L));
1522 E := First_Entity (Id);
1523 while Present (E) loop
1525 -- Check rule of 3.6(11), which in general requires waiting till all
1526 -- full types have been seen.
1528 if Ekind (E) = E_Record_Type or else Ekind (E) = E_Array_Type then
1529 Check_Aliased_Component_Types (E);
1532 -- Check preelaborable initialization for full type completing a
1533 -- private type for which pragma Preelaborable_Initialization given.
1536 and then Must_Have_Preelab_Init (E)
1537 and then not Has_Preelaborable_Initialization (E)
1540 ("full view of & does not have preelaborable initialization", E);
1543 -- An invariant may appear on a full view of a type
1546 and then Has_Private_Declaration (E)
1547 and then Nkind (Parent (E)) = N_Full_Type_Declaration
1548 and then Has_Aspects (Parent (E))
1554 ASN := First (Aspect_Specifications (Parent (E)));
1555 while Present (ASN) loop
1556 if Nam_In (Chars (Identifier (ASN)), Name_Invariant,
1557 Name_Type_Invariant)
1559 Build_Invariant_Procedure (E, N);
1571 -- Ada 2005 (AI-216): The completion of an incomplete or private type
1572 -- declaration having a known_discriminant_part shall not be an
1573 -- unchecked union type.
1575 if Present (Vis_Decls) then
1576 Inspect_Unchecked_Union_Completion (Vis_Decls);
1579 if Present (Priv_Decls) then
1580 Inspect_Unchecked_Union_Completion (Priv_Decls);
1583 if Ekind (Id) = E_Generic_Package
1584 and then Nkind (Orig_Decl) = N_Generic_Package_Declaration
1585 and then Present (Priv_Decls)
1587 -- Save global references in private declarations, ignoring the
1588 -- visible declarations that were processed earlier.
1591 Orig_Spec : constant Node_Id := Specification (Orig_Decl);
1592 Save_Vis : constant List_Id := Visible_Declarations (Orig_Spec);
1593 Save_Form : constant List_Id :=
1594 Generic_Formal_Declarations (Orig_Decl);
1597 Set_Visible_Declarations (Orig_Spec, Empty_List);
1598 Set_Generic_Formal_Declarations (Orig_Decl, Empty_List);
1599 Save_Global_References (Orig_Decl);
1600 Set_Generic_Formal_Declarations (Orig_Decl, Save_Form);
1601 Set_Visible_Declarations (Orig_Spec, Save_Vis);
1605 Process_End_Label (N, 'e', Id);
1607 -- Remove private_with_clauses of enclosing compilation unit, if they
1610 if Private_With_Clauses_Installed then
1611 Remove_Private_With_Clauses (Cunit (Current_Sem_Unit));
1614 -- For the case of a library level package, we must go through all the
1615 -- entities clearing the indications that the value may be constant and
1616 -- not modified. Why? Because any client of this package may modify
1617 -- these values freely from anywhere. This also applies to any nested
1618 -- packages or generic packages.
1620 -- For now we unconditionally clear constants for packages that are
1621 -- instances of generic packages. The reason is that we do not have the
1622 -- body yet, and we otherwise think things are unreferenced when they
1623 -- are not. This should be fixed sometime (the effect is not terrible,
1624 -- we just lose some warnings, and also some cases of value propagation)
1627 if Is_Library_Level_Entity (Id)
1628 or else Is_Generic_Instance (Id)
1630 Clear_Constants (Id, First_Entity (Id));
1631 Clear_Constants (Id, First_Private_Entity (Id));
1634 -- Issue an error in SPARK mode if a package specification contains
1635 -- more than one tagged type or type extension.
1637 Check_One_Tagged_Type_Or_Extension_At_Most;
1639 -- If switch set, output information on why body required
1641 if List_Body_Required_Info
1642 and then In_Extended_Main_Source_Unit (Id)
1643 and then Unit_Requires_Body (Id)
1645 Unit_Requires_Body_Info (Id);
1647 end Analyze_Package_Specification;
1649 --------------------------------------
1650 -- Analyze_Private_Type_Declaration --
1651 --------------------------------------
1653 procedure Analyze_Private_Type_Declaration (N : Node_Id) is
1654 PF : constant Boolean := Is_Pure (Enclosing_Lib_Unit_Entity);
1655 Id : constant Entity_Id := Defining_Identifier (N);
1658 Generate_Definition (Id);
1659 Set_Is_Pure (Id, PF);
1660 Init_Size_Align (Id);
1662 if not Is_Package_Or_Generic_Package (Current_Scope)
1663 or else In_Private_Part (Current_Scope)
1665 Error_Msg_N ("invalid context for private declaration", N);
1668 New_Private_Type (N, Id, N);
1669 Set_Depends_On_Private (Id);
1671 if Has_Aspects (N) then
1672 Analyze_Aspect_Specifications (N, Id);
1674 end Analyze_Private_Type_Declaration;
1676 ----------------------------------
1677 -- Check_Anonymous_Access_Types --
1678 ----------------------------------
1680 procedure Check_Anonymous_Access_Types
1681 (Spec_Id : Entity_Id;
1688 -- Itype references are only needed by gigi, to force elaboration of
1689 -- itypes. In the absence of code generation, they are not needed.
1691 if not Expander_Active then
1695 E := First_Entity (Spec_Id);
1696 while Present (E) loop
1697 if Ekind (E) = E_Anonymous_Access_Type
1698 and then From_Limited_With (E)
1700 IR := Make_Itype_Reference (Sloc (P_Body));
1703 if No (Declarations (P_Body)) then
1704 Set_Declarations (P_Body, New_List (IR));
1706 Prepend (IR, Declarations (P_Body));
1712 end Check_Anonymous_Access_Types;
1714 -------------------------------------------
1715 -- Declare_Inherited_Private_Subprograms --
1716 -------------------------------------------
1718 procedure Declare_Inherited_Private_Subprograms (Id : Entity_Id) is
1720 function Is_Primitive_Of (T : Entity_Id; S : Entity_Id) return Boolean;
1721 -- Check whether an inherited subprogram S is an operation of an
1722 -- untagged derived type T.
1724 ---------------------
1725 -- Is_Primitive_Of --
1726 ---------------------
1728 function Is_Primitive_Of (T : Entity_Id; S : Entity_Id) return Boolean is
1732 -- If the full view is a scalar type, the type is the anonymous base
1733 -- type, but the operation mentions the first subtype, so check the
1734 -- signature against the base type.
1736 if Base_Type (Etype (S)) = Base_Type (T) then
1740 Formal := First_Formal (S);
1741 while Present (Formal) loop
1742 if Base_Type (Etype (Formal)) = Base_Type (T) then
1746 Next_Formal (Formal);
1751 end Is_Primitive_Of;
1758 Op_Elmt_2 : Elmt_Id;
1759 Prim_Op : Entity_Id;
1760 New_Op : Entity_Id := Empty;
1761 Parent_Subp : Entity_Id;
1764 -- Start of processing for Declare_Inherited_Private_Subprograms
1767 E := First_Entity (Id);
1768 while Present (E) loop
1770 -- If the entity is a nonprivate type extension whose parent type
1771 -- is declared in an open scope, then the type may have inherited
1772 -- operations that now need to be made visible. Ditto if the entity
1773 -- is a formal derived type in a child unit.
1775 if ((Is_Derived_Type (E) and then not Is_Private_Type (E))
1777 (Nkind (Parent (E)) = N_Private_Extension_Declaration
1778 and then Is_Generic_Type (E)))
1779 and then In_Open_Scopes (Scope (Etype (E)))
1780 and then Is_Base_Type (E)
1782 if Is_Tagged_Type (E) then
1783 Op_List := Primitive_Operations (E);
1785 Tag := First_Tag_Component (E);
1787 Op_Elmt := First_Elmt (Op_List);
1788 while Present (Op_Elmt) loop
1789 Prim_Op := Node (Op_Elmt);
1791 -- Search primitives that are implicit operations with an
1792 -- internal name whose parent operation has a normal name.
1794 if Present (Alias (Prim_Op))
1795 and then Find_Dispatching_Type (Alias (Prim_Op)) /= E
1796 and then not Comes_From_Source (Prim_Op)
1797 and then Is_Internal_Name (Chars (Prim_Op))
1798 and then not Is_Internal_Name (Chars (Alias (Prim_Op)))
1800 Parent_Subp := Alias (Prim_Op);
1802 -- Case 1: Check if the type has also an explicit
1803 -- overriding for this primitive.
1805 Op_Elmt_2 := Next_Elmt (Op_Elmt);
1806 while Present (Op_Elmt_2) loop
1808 -- Skip entities with attribute Interface_Alias since
1809 -- they are not overriding primitives (these entities
1810 -- link an interface primitive with their covering
1813 if Chars (Node (Op_Elmt_2)) = Chars (Parent_Subp)
1814 and then Type_Conformant (Prim_Op, Node (Op_Elmt_2))
1815 and then No (Interface_Alias (Node (Op_Elmt_2)))
1817 -- The private inherited operation has been
1818 -- overridden by an explicit subprogram:
1819 -- replace the former by the latter.
1821 New_Op := Node (Op_Elmt_2);
1822 Replace_Elmt (Op_Elmt, New_Op);
1823 Remove_Elmt (Op_List, Op_Elmt_2);
1824 Set_Overridden_Operation (New_Op, Parent_Subp);
1826 -- We don't need to inherit its dispatching slot.
1827 -- Set_All_DT_Position has previously ensured that
1828 -- the same slot was assigned to the two primitives
1831 and then Present (DTC_Entity (New_Op))
1832 and then Present (DTC_Entity (Prim_Op))
1835 (DT_Position (New_Op) = DT_Position (Prim_Op));
1839 goto Next_Primitive;
1842 Next_Elmt (Op_Elmt_2);
1845 -- Case 2: We have not found any explicit overriding and
1846 -- hence we need to declare the operation (i.e., make it
1849 Derive_Subprogram (New_Op, Alias (Prim_Op), E, Etype (E));
1851 -- Inherit the dispatching slot if E is already frozen
1854 and then Present (DTC_Entity (Alias (Prim_Op)))
1856 Set_DTC_Entity_Value (E, New_Op);
1857 Set_DT_Position (New_Op,
1858 DT_Position (Alias (Prim_Op)));
1862 (Is_Dispatching_Operation (New_Op)
1863 and then Node (Last_Elmt (Op_List)) = New_Op);
1865 -- Substitute the new operation for the old one in the
1866 -- type's primitive operations list. Since the new
1867 -- operation was also just added to the end of list,
1868 -- the last element must be removed.
1870 -- (Question: is there a simpler way of declaring the
1871 -- operation, say by just replacing the name of the
1872 -- earlier operation, reentering it in the in the symbol
1873 -- table (how?), and marking it as private???)
1875 Replace_Elmt (Op_Elmt, New_Op);
1876 Remove_Last_Elmt (Op_List);
1880 Next_Elmt (Op_Elmt);
1883 -- Generate listing showing the contents of the dispatch table
1885 if Debug_Flag_ZZ then
1890 -- For untagged type, scan forward to locate inherited hidden
1893 Prim_Op := Next_Entity (E);
1894 while Present (Prim_Op) loop
1895 if Is_Subprogram (Prim_Op)
1896 and then Present (Alias (Prim_Op))
1897 and then not Comes_From_Source (Prim_Op)
1898 and then Is_Internal_Name (Chars (Prim_Op))
1899 and then not Is_Internal_Name (Chars (Alias (Prim_Op)))
1900 and then Is_Primitive_Of (E, Prim_Op)
1902 Derive_Subprogram (New_Op, Alias (Prim_Op), E, Etype (E));
1905 Next_Entity (Prim_Op);
1907 -- Derived operations appear immediately after the type
1908 -- declaration (or the following subtype indication for
1909 -- a derived scalar type). Further declarations cannot
1910 -- include inherited operations of the type.
1912 if Present (Prim_Op) then
1913 exit when Ekind (Prim_Op) not in Overloadable_Kind;
1921 end Declare_Inherited_Private_Subprograms;
1923 -----------------------
1924 -- End_Package_Scope --
1925 -----------------------
1927 procedure End_Package_Scope (P : Entity_Id) is
1929 Uninstall_Declarations (P);
1931 end End_Package_Scope;
1933 ---------------------------
1934 -- Exchange_Declarations --
1935 ---------------------------
1937 procedure Exchange_Declarations (Id : Entity_Id) is
1938 Full_Id : constant Entity_Id := Full_View (Id);
1939 H1 : constant Entity_Id := Homonym (Id);
1940 Next1 : constant Entity_Id := Next_Entity (Id);
1945 -- If missing full declaration for type, nothing to exchange
1947 if No (Full_Id) then
1951 -- Otherwise complete the exchange, and preserve semantic links
1953 Next2 := Next_Entity (Full_Id);
1954 H2 := Homonym (Full_Id);
1956 -- Reset full declaration pointer to reflect the switched entities and
1957 -- readjust the next entity chains.
1959 Exchange_Entities (Id, Full_Id);
1961 Set_Next_Entity (Id, Next1);
1962 Set_Homonym (Id, H1);
1964 Set_Full_View (Full_Id, Id);
1965 Set_Next_Entity (Full_Id, Next2);
1966 Set_Homonym (Full_Id, H2);
1967 end Exchange_Declarations;
1969 ----------------------------
1970 -- Install_Package_Entity --
1971 ----------------------------
1973 procedure Install_Package_Entity (Id : Entity_Id) is
1975 if not Is_Internal (Id) then
1976 if Debug_Flag_E then
1977 Write_Str ("Install: ");
1978 Write_Name (Chars (Id));
1982 if Is_Child_Unit (Id) then
1985 -- Do not enter implicitly inherited non-overridden subprograms of
1986 -- a tagged type back into visibility if they have non-conformant
1987 -- homographs (Ada RM 8.3 12.3/2).
1989 elsif Is_Hidden_Non_Overridden_Subpgm (Id) then
1993 Set_Is_Immediately_Visible (Id);
1996 end Install_Package_Entity;
1998 ----------------------------------
1999 -- Install_Private_Declarations --
2000 ----------------------------------
2002 procedure Install_Private_Declarations (P : Entity_Id) is
2005 Priv_Deps : Elist_Id;
2007 procedure Swap_Private_Dependents (Priv_Deps : Elist_Id);
2008 -- When the full view of a private type is made available, we do the
2009 -- same for its private dependents under proper visibility conditions.
2010 -- When compiling a grand-chid unit this needs to be done recursively.
2012 -----------------------------
2013 -- Swap_Private_Dependents --
2014 -----------------------------
2016 procedure Swap_Private_Dependents (Priv_Deps : Elist_Id) is
2019 Priv_Elmt : Elmt_Id;
2023 Priv_Elmt := First_Elmt (Priv_Deps);
2024 while Present (Priv_Elmt) loop
2025 Priv := Node (Priv_Elmt);
2027 -- Before the exchange, verify that the presence of the Full_View
2028 -- field. This field will be empty if the entity has already been
2029 -- installed due to a previous call.
2031 if Present (Full_View (Priv)) and then Is_Visible_Dependent (Priv)
2033 if Is_Private_Type (Priv) then
2034 Deps := Private_Dependents (Priv);
2040 -- For each subtype that is swapped, we also swap the reference
2041 -- to it in Private_Dependents, to allow access to it when we
2042 -- swap them out in End_Package_Scope.
2044 Replace_Elmt (Priv_Elmt, Full_View (Priv));
2045 Exchange_Declarations (Priv);
2046 Set_Is_Immediately_Visible
2047 (Priv, In_Open_Scopes (Scope (Priv)));
2048 Set_Is_Potentially_Use_Visible
2049 (Priv, Is_Potentially_Use_Visible (Node (Priv_Elmt)));
2051 -- Within a child unit, recurse, except in generic child unit,
2052 -- which (unfortunately) handle private_dependents separately.
2055 and then Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
2056 and then not Is_Empty_Elmt_List (Deps)
2057 and then not Inside_A_Generic
2059 Swap_Private_Dependents (Deps);
2063 Next_Elmt (Priv_Elmt);
2065 end Swap_Private_Dependents;
2067 -- Start of processing for Install_Private_Declarations
2070 -- First exchange declarations for private types, so that the full
2071 -- declaration is visible. For each private type, we check its
2072 -- Private_Dependents list and also exchange any subtypes of or derived
2073 -- types from it. Finally, if this is a Taft amendment type, the
2074 -- incomplete declaration is irrelevant, and we want to link the
2075 -- eventual full declaration with the original private one so we
2076 -- also skip the exchange.
2078 Id := First_Entity (P);
2079 while Present (Id) and then Id /= First_Private_Entity (P) loop
2080 if Is_Private_Base_Type (Id)
2081 and then Present (Full_View (Id))
2082 and then Comes_From_Source (Full_View (Id))
2083 and then Scope (Full_View (Id)) = Scope (Id)
2084 and then Ekind (Full_View (Id)) /= E_Incomplete_Type
2086 -- If there is a use-type clause on the private type, set the full
2087 -- view accordingly.
2089 Set_In_Use (Full_View (Id), In_Use (Id));
2090 Full := Full_View (Id);
2092 if Is_Private_Base_Type (Full)
2093 and then Has_Private_Declaration (Full)
2094 and then Nkind (Parent (Full)) = N_Full_Type_Declaration
2095 and then In_Open_Scopes (Scope (Etype (Full)))
2096 and then In_Package_Body (Current_Scope)
2097 and then not Is_Private_Type (Etype (Full))
2099 -- This is the completion of a private type by a derivation
2100 -- from another private type which is not private anymore. This
2101 -- can only happen in a package nested within a child package,
2102 -- when the parent type is defined in the parent unit. At this
2103 -- point the current type is not private either, and we have
2104 -- to install the underlying full view, which is now visible.
2105 -- Save the current full view as well, so that all views can be
2106 -- restored on exit. It may seem that after compiling the child
2107 -- body there are not environments to restore, but the back-end
2108 -- expects those links to be valid, and freeze nodes depend on
2111 if No (Full_View (Full))
2112 and then Present (Underlying_Full_View (Full))
2114 Set_Full_View (Id, Underlying_Full_View (Full));
2115 Set_Underlying_Full_View (Id, Full);
2117 Set_Underlying_Full_View (Full, Empty);
2118 Set_Is_Frozen (Full_View (Id));
2122 Priv_Deps := Private_Dependents (Id);
2123 Exchange_Declarations (Id);
2124 Set_Is_Immediately_Visible (Id);
2125 Swap_Private_Dependents (Priv_Deps);
2131 -- Next make other declarations in the private part visible as well
2133 Id := First_Private_Entity (P);
2134 while Present (Id) loop
2135 Install_Package_Entity (Id);
2136 Set_Is_Hidden (Id, False);
2140 -- Indicate that the private part is currently visible, so it can be
2141 -- properly reset on exit.
2143 Set_In_Private_Part (P);
2144 end Install_Private_Declarations;
2146 ----------------------------------
2147 -- Install_Visible_Declarations --
2148 ----------------------------------
2150 procedure Install_Visible_Declarations (P : Entity_Id) is
2152 Last_Entity : Entity_Id;
2156 (Is_Package_Or_Generic_Package (P) or else Is_Record_Type (P));
2158 if Is_Package_Or_Generic_Package (P) then
2159 Last_Entity := First_Private_Entity (P);
2161 Last_Entity := Empty;
2164 Id := First_Entity (P);
2165 while Present (Id) and then Id /= Last_Entity loop
2166 Install_Package_Entity (Id);
2169 end Install_Visible_Declarations;
2171 --------------------------
2172 -- Is_Private_Base_Type --
2173 --------------------------
2175 function Is_Private_Base_Type (E : Entity_Id) return Boolean is
2177 return Ekind (E) = E_Private_Type
2178 or else Ekind (E) = E_Limited_Private_Type
2179 or else Ekind (E) = E_Record_Type_With_Private;
2180 end Is_Private_Base_Type;
2182 --------------------------
2183 -- Is_Visible_Dependent --
2184 --------------------------
2186 function Is_Visible_Dependent (Dep : Entity_Id) return Boolean
2188 S : constant Entity_Id := Scope (Dep);
2191 -- Renamings created for actual types have the visibility of the actual
2193 if Ekind (S) = E_Package
2194 and then Is_Generic_Instance (S)
2195 and then (Is_Generic_Actual_Type (Dep)
2196 or else Is_Generic_Actual_Type (Full_View (Dep)))
2200 elsif not (Is_Derived_Type (Dep))
2201 and then Is_Derived_Type (Full_View (Dep))
2203 -- When instantiating a package body, the scope stack is empty, so
2204 -- check instead whether the dependent type is defined in the same
2205 -- scope as the instance itself.
2207 return In_Open_Scopes (S)
2208 or else (Is_Generic_Instance (Current_Scope)
2209 and then Scope (Dep) = Scope (Current_Scope));
2213 end Is_Visible_Dependent;
2215 ----------------------------
2216 -- May_Need_Implicit_Body --
2217 ----------------------------
2219 procedure May_Need_Implicit_Body (E : Entity_Id) is
2220 P : constant Node_Id := Unit_Declaration_Node (E);
2221 S : constant Node_Id := Parent (P);
2226 if not Has_Completion (E)
2227 and then Nkind (P) = N_Package_Declaration
2228 and then (Present (Activation_Chain_Entity (P)) or else Has_RACW (E))
2231 Make_Package_Body (Sloc (E),
2232 Defining_Unit_Name => Make_Defining_Identifier (Sloc (E),
2233 Chars => Chars (E)),
2234 Declarations => New_List);
2236 if Nkind (S) = N_Package_Specification then
2237 if Present (Private_Declarations (S)) then
2238 Decls := Private_Declarations (S);
2240 Decls := Visible_Declarations (S);
2243 Decls := Declarations (S);
2249 end May_Need_Implicit_Body;
2251 ----------------------
2252 -- New_Private_Type --
2253 ----------------------
2255 procedure New_Private_Type (N : Node_Id; Id : Entity_Id; Def : Node_Id) is
2257 -- For other than Ada 2012, enter the name in the current scope
2259 if Ada_Version < Ada_2012 then
2262 -- Ada 2012 (AI05-0162): Enter the name in the current scope. Note that
2263 -- there may be an incomplete previous view.
2269 Prev := Find_Type_Name (N);
2270 pragma Assert (Prev = Id
2271 or else (Ekind (Prev) = E_Incomplete_Type
2272 and then Present (Full_View (Prev))
2273 and then Full_View (Prev) = Id));
2277 if Limited_Present (Def) then
2278 Set_Ekind (Id, E_Limited_Private_Type);
2280 Set_Ekind (Id, E_Private_Type);
2284 Set_Has_Delayed_Freeze (Id);
2285 Set_Is_First_Subtype (Id);
2286 Init_Size_Align (Id);
2288 Set_Is_Constrained (Id,
2289 No (Discriminant_Specifications (N))
2290 and then not Unknown_Discriminants_Present (N));
2292 -- Set tagged flag before processing discriminants, to catch illegal
2295 Set_Is_Tagged_Type (Id, Tagged_Present (Def));
2297 Set_Discriminant_Constraint (Id, No_Elist);
2298 Set_Stored_Constraint (Id, No_Elist);
2300 if Present (Discriminant_Specifications (N)) then
2302 Process_Discriminants (N);
2305 elsif Unknown_Discriminants_Present (N) then
2306 Set_Has_Unknown_Discriminants (Id);
2309 Set_Private_Dependents (Id, New_Elmt_List);
2311 if Tagged_Present (Def) then
2312 Set_Ekind (Id, E_Record_Type_With_Private);
2313 Set_Direct_Primitive_Operations (Id, New_Elmt_List);
2314 Set_Is_Abstract_Type (Id, Abstract_Present (Def));
2315 Set_Is_Limited_Record (Id, Limited_Present (Def));
2316 Set_Has_Delayed_Freeze (Id, True);
2318 -- Create a class-wide type with the same attributes
2320 Make_Class_Wide_Type (Id);
2322 elsif Abstract_Present (Def) then
2323 Error_Msg_N ("only a tagged type can be abstract", N);
2325 end New_Private_Type;
2327 ----------------------------
2328 -- Uninstall_Declarations --
2329 ----------------------------
2331 procedure Uninstall_Declarations (P : Entity_Id) is
2332 Decl : constant Node_Id := Unit_Declaration_Node (P);
2335 Priv_Elmt : Elmt_Id;
2336 Priv_Sub : Entity_Id;
2338 procedure Preserve_Full_Attributes (Priv, Full : Entity_Id);
2339 -- Copy to the private declaration the attributes of the full view that
2340 -- need to be available for the partial view also.
2342 function Type_In_Use (T : Entity_Id) return Boolean;
2343 -- Check whether type or base type appear in an active use_type clause
2345 ------------------------------
2346 -- Preserve_Full_Attributes --
2347 ------------------------------
2349 procedure Preserve_Full_Attributes (Priv, Full : Entity_Id) is
2350 Priv_Is_Base_Type : constant Boolean := Is_Base_Type (Priv);
2353 Set_Size_Info (Priv, (Full));
2354 Set_RM_Size (Priv, RM_Size (Full));
2355 Set_Size_Known_At_Compile_Time
2356 (Priv, Size_Known_At_Compile_Time (Full));
2357 Set_Is_Volatile (Priv, Is_Volatile (Full));
2358 Set_Treat_As_Volatile (Priv, Treat_As_Volatile (Full));
2359 Set_Is_Ada_2005_Only (Priv, Is_Ada_2005_Only (Full));
2360 Set_Is_Ada_2012_Only (Priv, Is_Ada_2012_Only (Full));
2361 Set_Has_Pragma_Unmodified (Priv, Has_Pragma_Unmodified (Full));
2362 Set_Has_Pragma_Unreferenced (Priv, Has_Pragma_Unreferenced (Full));
2363 Set_Has_Pragma_Unreferenced_Objects
2364 (Priv, Has_Pragma_Unreferenced_Objects
2366 if Is_Unchecked_Union (Full) then
2367 Set_Is_Unchecked_Union (Base_Type (Priv));
2369 -- Why is atomic not copied here ???
2371 if Referenced (Full) then
2372 Set_Referenced (Priv);
2375 if Priv_Is_Base_Type then
2376 Set_Is_Controlled (Priv, Is_Controlled (Base_Type (Full)));
2377 Set_Finalize_Storage_Only
2378 (Priv, Finalize_Storage_Only
2379 (Base_Type (Full)));
2380 Set_Has_Task (Priv, Has_Task (Base_Type (Full)));
2381 Set_Has_Protected (Priv, Has_Protected (Base_Type (Full)));
2382 Set_Has_Controlled_Component
2383 (Priv, Has_Controlled_Component
2384 (Base_Type (Full)));
2387 Set_Freeze_Node (Priv, Freeze_Node (Full));
2389 -- Propagate information of type invariants, which may be specified
2390 -- for the full view.
2392 if Has_Invariants (Full) and not Has_Invariants (Priv) then
2393 Set_Has_Invariants (Priv);
2394 Set_Subprograms_For_Type (Priv, Subprograms_For_Type (Full));
2397 if Is_Tagged_Type (Priv)
2398 and then Is_Tagged_Type (Full)
2399 and then not Error_Posted (Full)
2401 if Is_Tagged_Type (Priv) then
2403 -- If the type is tagged, the tag itself must be available on
2404 -- the partial view, for expansion purposes.
2406 Set_First_Entity (Priv, First_Entity (Full));
2408 -- If there are discriminants in the partial view, these remain
2409 -- visible. Otherwise only the tag itself is visible, and there
2410 -- are no nameable components in the partial view.
2412 if No (Last_Entity (Priv)) then
2413 Set_Last_Entity (Priv, First_Entity (Priv));
2417 Set_Has_Discriminants (Priv, Has_Discriminants (Full));
2419 if Has_Discriminants (Full) then
2420 Set_Discriminant_Constraint (Priv,
2421 Discriminant_Constraint (Full));
2424 end Preserve_Full_Attributes;
2430 function Type_In_Use (T : Entity_Id) return Boolean is
2432 return Scope (Base_Type (T)) = P
2433 and then (In_Use (T) or else In_Use (Base_Type (T)));
2436 -- Start of processing for Uninstall_Declarations
2439 Id := First_Entity (P);
2440 while Present (Id) and then Id /= First_Private_Entity (P) loop
2441 if Debug_Flag_E then
2442 Write_Str ("unlinking visible entity ");
2443 Write_Int (Int (Id));
2447 -- On exit from the package scope, we must preserve the visibility
2448 -- established by use clauses in the current scope. Two cases:
2450 -- a) If the entity is an operator, it may be a primitive operator of
2451 -- a type for which there is a visible use-type clause.
2453 -- b) for other entities, their use-visibility is determined by a
2454 -- visible use clause for the package itself. For a generic instance,
2455 -- the instantiation of the formals appears in the visible part,
2456 -- but the formals are private and remain so.
2458 if Ekind (Id) = E_Function
2459 and then Is_Operator_Symbol_Name (Chars (Id))
2460 and then not Is_Hidden (Id)
2461 and then not Error_Posted (Id)
2463 Set_Is_Potentially_Use_Visible (Id,
2465 or else Type_In_Use (Etype (Id))
2466 or else Type_In_Use (Etype (First_Formal (Id)))
2467 or else (Present (Next_Formal (First_Formal (Id)))
2470 (Etype (Next_Formal (First_Formal (Id))))));
2472 if In_Use (P) and then not Is_Hidden (Id) then
2474 -- A child unit of a use-visible package remains use-visible
2475 -- only if it is itself a visible child unit. Otherwise it
2476 -- would remain visible in other contexts where P is use-
2477 -- visible, because once compiled it stays in the entity list
2478 -- of its parent unit.
2480 if Is_Child_Unit (Id) then
2481 Set_Is_Potentially_Use_Visible
2482 (Id, Is_Visible_Lib_Unit (Id));
2484 Set_Is_Potentially_Use_Visible (Id);
2488 Set_Is_Potentially_Use_Visible (Id, False);
2492 -- Local entities are not immediately visible outside of the package
2494 Set_Is_Immediately_Visible (Id, False);
2496 -- If this is a private type with a full view (for example a local
2497 -- subtype of a private type declared elsewhere), ensure that the
2498 -- full view is also removed from visibility: it may be exposed when
2499 -- swapping views in an instantiation.
2501 if Is_Type (Id) and then Present (Full_View (Id)) then
2502 Set_Is_Immediately_Visible (Full_View (Id), False);
2505 if Is_Tagged_Type (Id) and then Ekind (Id) = E_Record_Type then
2506 Check_Abstract_Overriding (Id);
2507 Check_Conventions (Id);
2510 if Ekind_In (Id, E_Private_Type, E_Limited_Private_Type)
2511 and then No (Full_View (Id))
2512 and then not Is_Generic_Type (Id)
2513 and then not Is_Derived_Type (Id)
2515 Error_Msg_N ("missing full declaration for private type&", Id);
2517 elsif Ekind (Id) = E_Record_Type_With_Private
2518 and then not Is_Generic_Type (Id)
2519 and then No (Full_View (Id))
2521 if Nkind (Parent (Id)) = N_Private_Type_Declaration then
2522 Error_Msg_N ("missing full declaration for private type&", Id);
2525 ("missing full declaration for private extension", Id);
2528 -- Case of constant, check for deferred constant declaration with
2529 -- no full view. Likely just a matter of a missing expression, or
2530 -- accidental use of the keyword constant.
2532 elsif Ekind (Id) = E_Constant
2534 -- OK if constant value present
2536 and then No (Constant_Value (Id))
2538 -- OK if full view present
2540 and then No (Full_View (Id))
2542 -- OK if imported, since that provides the completion
2544 and then not Is_Imported (Id)
2546 -- OK if object declaration replaced by renaming declaration as
2547 -- a result of OK_To_Rename processing (e.g. for concatenation)
2549 and then Nkind (Parent (Id)) /= N_Object_Renaming_Declaration
2551 -- OK if object declaration with the No_Initialization flag set
2553 and then not (Nkind (Parent (Id)) = N_Object_Declaration
2554 and then No_Initialization (Parent (Id)))
2556 -- If no private declaration is present, we assume the user did
2557 -- not intend a deferred constant declaration and the problem
2558 -- is simply that the initializing expression is missing.
2560 if not Has_Private_Declaration (Etype (Id)) then
2562 -- We assume that the user did not intend a deferred constant
2563 -- declaration, and the expression is just missing.
2566 ("constant declaration requires initialization expression",
2569 if Is_Limited_Type (Etype (Id)) then
2571 ("\if variable intended, remove CONSTANT from declaration",
2575 -- Otherwise if a private declaration is present, then we are
2576 -- missing the full declaration for the deferred constant.
2580 ("missing full declaration for deferred constant (RM 7.4)",
2583 if Is_Limited_Type (Etype (Id)) then
2585 ("\if variable intended, remove CONSTANT from declaration",
2594 -- If the specification was installed as the parent of a public child
2595 -- unit, the private declarations were not installed, and there is
2598 if not In_Private_Part (P) then
2601 Set_In_Private_Part (P, False);
2604 -- Make private entities invisible and exchange full and private
2605 -- declarations for private types. Id is now the first private entity
2608 while Present (Id) loop
2609 if Debug_Flag_E then
2610 Write_Str ("unlinking private entity ");
2611 Write_Int (Int (Id));
2615 if Is_Tagged_Type (Id) and then Ekind (Id) = E_Record_Type then
2616 Check_Abstract_Overriding (Id);
2617 Check_Conventions (Id);
2620 Set_Is_Immediately_Visible (Id, False);
2622 if Is_Private_Base_Type (Id) and then Present (Full_View (Id)) then
2623 Full := Full_View (Id);
2625 -- If the partial view is not declared in the visible part of the
2626 -- package (as is the case when it is a type derived from some
2627 -- other private type in the private part of the current package),
2628 -- no exchange takes place.
2631 or else List_Containing (Parent (Id)) /=
2632 Visible_Declarations (Specification (Decl))
2637 -- The entry in the private part points to the full declaration,
2638 -- which is currently visible. Exchange them so only the private
2639 -- type declaration remains accessible, and link private and full
2640 -- declaration in the opposite direction. Before the actual
2641 -- exchange, we copy back attributes of the full view that must
2642 -- be available to the partial view too.
2644 Preserve_Full_Attributes (Id, Full);
2646 Set_Is_Potentially_Use_Visible (Id, In_Use (P));
2648 -- The following test may be redundant, as this is already
2649 -- diagnosed in sem_ch3. ???
2651 if Is_Indefinite_Subtype (Full)
2652 and then not Is_Indefinite_Subtype (Id)
2654 Error_Msg_Sloc := Sloc (Parent (Id));
2656 ("full view of& not compatible with declaration#", Full, Id);
2659 -- Swap out the subtypes and derived types of Id that
2660 -- were compiled in this scope, or installed previously
2661 -- by Install_Private_Declarations.
2663 -- Before we do the swap, we verify the presence of the Full_View
2664 -- field which may be empty due to a swap by a previous call to
2665 -- End_Package_Scope (e.g. from the freezing mechanism).
2667 Priv_Elmt := First_Elmt (Private_Dependents (Id));
2668 while Present (Priv_Elmt) loop
2669 Priv_Sub := Node (Priv_Elmt);
2671 if Present (Full_View (Priv_Sub)) then
2672 if Scope (Priv_Sub) = P
2673 or else not In_Open_Scopes (Scope (Priv_Sub))
2675 Set_Is_Immediately_Visible (Priv_Sub, False);
2678 if Is_Visible_Dependent (Priv_Sub) then
2679 Preserve_Full_Attributes
2680 (Priv_Sub, Full_View (Priv_Sub));
2681 Replace_Elmt (Priv_Elmt, Full_View (Priv_Sub));
2682 Exchange_Declarations (Priv_Sub);
2686 Next_Elmt (Priv_Elmt);
2689 -- Now restore the type itself to its private view
2691 Exchange_Declarations (Id);
2693 -- If we have installed an underlying full view for a type derived
2694 -- from a private type in a child unit, restore the proper views
2695 -- of private and full view. See corresponding code in
2696 -- Install_Private_Declarations.
2698 -- After the exchange, Full denotes the private type in the
2699 -- visible part of the package.
2701 if Is_Private_Base_Type (Full)
2702 and then Present (Full_View (Full))
2703 and then Present (Underlying_Full_View (Full))
2704 and then In_Package_Body (Current_Scope)
2706 Set_Full_View (Full, Underlying_Full_View (Full));
2707 Set_Underlying_Full_View (Full, Empty);
2710 elsif Ekind (Id) = E_Incomplete_Type
2711 and then Comes_From_Source (Id)
2712 and then No (Full_View (Id))
2714 -- Mark Taft amendment types. Verify that there are no primitive
2715 -- operations declared for the type (3.10.1(9)).
2717 Set_Has_Completion_In_Body (Id);
2724 Elmt := First_Elmt (Private_Dependents (Id));
2725 while Present (Elmt) loop
2726 Subp := Node (Elmt);
2728 -- Is_Primitive is tested because there can be cases where
2729 -- nonprimitive subprograms (in nested packages) are added
2730 -- to the Private_Dependents list.
2732 if Is_Overloadable (Subp) and then Is_Primitive (Subp) then
2734 ("type& must be completed in the private part",
2737 -- The result type of an access-to-function type cannot be a
2738 -- Taft-amendment type, unless the version is Ada 2012 or
2739 -- later (see AI05-151).
2741 elsif Ada_Version < Ada_2012
2742 and then Ekind (Subp) = E_Subprogram_Type
2744 if Etype (Subp) = Id
2746 (Is_Class_Wide_Type (Etype (Subp))
2747 and then Etype (Etype (Subp)) = Id)
2750 ("type& must be completed in the private part",
2751 Associated_Node_For_Itype (Subp), Id);
2759 elsif not Is_Child_Unit (Id)
2760 and then (not Is_Private_Type (Id) or else No (Full_View (Id)))
2763 Set_Is_Potentially_Use_Visible (Id, False);
2769 end Uninstall_Declarations;
2771 ------------------------
2772 -- Unit_Requires_Body --
2773 ------------------------
2775 function Unit_Requires_Body
2777 Ignore_Abstract_State : Boolean := False) return Boolean
2782 -- Imported entity never requires body. Right now, only subprograms can
2783 -- be imported, but perhaps in the future we will allow import of
2786 if Is_Imported (P) then
2789 -- Body required if library package with pragma Elaborate_Body
2791 elsif Has_Pragma_Elaborate_Body (P) then
2794 -- Body required if subprogram
2796 elsif Is_Subprogram (P) or else Is_Generic_Subprogram (P) then
2799 -- Treat a block as requiring a body
2801 elsif Ekind (P) = E_Block then
2804 elsif Ekind (P) = E_Package
2805 and then Nkind (Parent (P)) = N_Package_Specification
2806 and then Present (Generic_Parent (Parent (P)))
2809 G_P : constant Entity_Id := Generic_Parent (Parent (P));
2811 if Has_Pragma_Elaborate_Body (G_P) then
2816 -- A [generic] package that introduces at least one non-null abstract
2817 -- state requires completion. However, there is a separate rule that
2818 -- requires that such a package have a reason other than this for a
2819 -- body being required (if necessary a pragma Elaborate_Body must be
2820 -- provided). If Ignore_Abstract_State is True, we don't do this check
2821 -- (so we can use Unit_Requires_Body to check for some other reason).
2823 elsif Ekind_In (P, E_Generic_Package, E_Package)
2824 and then not Ignore_Abstract_State
2825 and then Present (Abstract_States (P))
2826 and then not Is_Null_State (Node (First_Elmt (Abstract_States (P))))
2831 -- Otherwise search entity chain for entity requiring completion
2833 E := First_Entity (P);
2834 while Present (E) loop
2836 -- Always ignore child units. Child units get added to the entity
2837 -- list of a parent unit, but are not original entities of the
2838 -- parent, and so do not affect whether the parent needs a body.
2840 if Is_Child_Unit (E) then
2843 -- Ignore formal packages and their renamings
2845 elsif Ekind (E) = E_Package
2846 and then Nkind (Original_Node (Unit_Declaration_Node (E))) =
2847 N_Formal_Package_Declaration
2851 -- Otherwise test to see if entity requires a completion.
2852 -- Note that subprogram entities whose declaration does not come
2853 -- from source are ignored here on the basis that we assume the
2854 -- expander will provide an implicit completion at some point.
2856 elsif (Is_Overloadable (E)
2857 and then Ekind (E) /= E_Enumeration_Literal
2858 and then Ekind (E) /= E_Operator
2859 and then not Is_Abstract_Subprogram (E)
2860 and then not Has_Completion (E)
2861 and then Comes_From_Source (Parent (E)))
2864 (Ekind (E) = E_Package
2866 and then not Has_Completion (E)
2867 and then Unit_Requires_Body (E))
2870 (Ekind (E) = E_Incomplete_Type
2871 and then No (Full_View (E))
2872 and then not Is_Generic_Type (E))
2875 (Ekind_In (E, E_Task_Type, E_Protected_Type)
2876 and then not Has_Completion (E))
2879 (Ekind (E) = E_Generic_Package
2881 and then not Has_Completion (E)
2882 and then Unit_Requires_Body (E))
2885 (Is_Generic_Subprogram (E)
2886 and then not Has_Completion (E))
2891 -- Entity that does not require completion
2901 end Unit_Requires_Body;
2903 -----------------------------
2904 -- Unit_Requires_Body_Info --
2905 -----------------------------
2907 procedure Unit_Requires_Body_Info (P : Entity_Id) is
2911 -- Imported entity never requires body. Right now, only subprograms can
2912 -- be imported, but perhaps in the future we will allow import of
2915 if Is_Imported (P) then
2918 -- Body required if library package with pragma Elaborate_Body
2920 elsif Has_Pragma_Elaborate_Body (P) then
2921 Error_Msg_N ("info: & requires body (Elaborate_Body)?Y?", P);
2923 -- Body required if subprogram
2925 elsif Is_Subprogram (P) or else Is_Generic_Subprogram (P) then
2926 Error_Msg_N ("info: & requires body (subprogram case)?Y?", P);
2928 -- Body required if generic parent has Elaborate_Body
2930 elsif Ekind (P) = E_Package
2931 and then Nkind (Parent (P)) = N_Package_Specification
2932 and then Present (Generic_Parent (Parent (P)))
2935 G_P : constant Entity_Id := Generic_Parent (Parent (P));
2937 if Has_Pragma_Elaborate_Body (G_P) then
2939 ("info: & requires body (generic parent Elaborate_Body)?Y?",
2944 -- A [generic] package that introduces at least one non-null abstract
2945 -- state requires completion. However, there is a separate rule that
2946 -- requires that such a package have a reason other than this for a
2947 -- body being required (if necessary a pragma Elaborate_Body must be
2948 -- provided). If Ignore_Abstract_State is True, we don't do this check
2949 -- (so we can use Unit_Requires_Body to check for some other reason).
2951 elsif Ekind_In (P, E_Generic_Package, E_Package)
2952 and then Present (Abstract_States (P))
2953 and then not Is_Null_State (Node (First_Elmt (Abstract_States (P))))
2956 ("info: & requires body (non-null abstract state aspect)?Y?", P);
2959 -- Otherwise search entity chain for entity requiring completion
2961 E := First_Entity (P);
2962 while Present (E) loop
2964 -- Always ignore child units. Child units get added to the entity
2965 -- list of a parent unit, but are not original entities of the
2966 -- parent, and so do not affect whether the parent needs a body.
2968 if Is_Child_Unit (E) then
2971 -- Ignore formal packages and their renamings
2973 elsif Ekind (E) = E_Package
2974 and then Nkind (Original_Node (Unit_Declaration_Node (E))) =
2975 N_Formal_Package_Declaration
2979 -- Otherwise test to see if entity requires a completion.
2980 -- Note that subprogram entities whose declaration does not come
2981 -- from source are ignored here on the basis that we assume the
2982 -- expander will provide an implicit completion at some point.
2984 elsif (Is_Overloadable (E)
2985 and then Ekind (E) /= E_Enumeration_Literal
2986 and then Ekind (E) /= E_Operator
2987 and then not Is_Abstract_Subprogram (E)
2988 and then not Has_Completion (E)
2989 and then Comes_From_Source (Parent (E)))
2992 (Ekind (E) = E_Package
2994 and then not Has_Completion (E)
2995 and then Unit_Requires_Body (E))
2998 (Ekind (E) = E_Incomplete_Type
2999 and then No (Full_View (E))
3000 and then not Is_Generic_Type (E))
3003 (Ekind_In (E, E_Task_Type, E_Protected_Type)
3004 and then not Has_Completion (E))
3007 (Ekind (E) = E_Generic_Package
3009 and then not Has_Completion (E)
3010 and then Unit_Requires_Body (E))
3013 (Is_Generic_Subprogram (E)
3014 and then not Has_Completion (E))
3016 Error_Msg_Node_2 := E;
3018 ("info: & requires body (& requires completion)?Y?", E, P);
3020 -- Entity that does not require completion
3028 end Unit_Requires_Body_Info;