1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2006, 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 2, 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 COPYING. If not, write --
19 -- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
20 -- Boston, MA 02110-1301, USA. --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
25 ------------------------------------------------------------------------------
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Einfo; use Einfo;
30 with Errout; use Errout;
31 with Exp_Ch9; use Exp_Ch9;
32 with Elists; use Elists;
33 with Freeze; use Freeze;
34 with Itypes; use Itypes;
35 with Lib.Xref; use Lib.Xref;
36 with Nlists; use Nlists;
37 with Nmake; use Nmake;
39 with Restrict; use Restrict;
40 with Rident; use Rident;
41 with Rtsfind; use Rtsfind;
43 with Sem_Ch3; use Sem_Ch3;
44 with Sem_Ch5; use Sem_Ch5;
45 with Sem_Ch6; use Sem_Ch6;
46 with Sem_Ch8; use Sem_Ch8;
47 with Sem_Eval; use Sem_Eval;
48 with Sem_Res; use Sem_Res;
49 with Sem_Type; use Sem_Type;
50 with Sem_Util; use Sem_Util;
51 with Sem_Warn; use Sem_Warn;
52 with Snames; use Snames;
53 with Stand; use Stand;
54 with Sinfo; use Sinfo;
56 with Tbuild; use Tbuild;
57 with Uintp; use Uintp;
59 package body Sem_Ch9 is
61 -----------------------
62 -- Local Subprograms --
63 -----------------------
65 procedure Check_Max_Entries (D : Node_Id; R : All_Parameter_Restrictions);
66 -- Given either a protected definition or a task definition in D, check
67 -- the corresponding restriction parameter identifier R, and if it is set,
68 -- count the entries (checking the static requirement), and compare with
71 function Find_Concurrent_Spec (Body_Id : Entity_Id) return Entity_Id;
72 -- Find entity in corresponding task or protected declaration. Use full
73 -- view if first declaration was for an incomplete type.
75 procedure Install_Declarations (Spec : Entity_Id);
76 -- Utility to make visible in corresponding body the entities defined in
77 -- task, protected type declaration, or entry declaration.
79 -----------------------------
80 -- Analyze_Abort_Statement --
81 -----------------------------
83 procedure Analyze_Abort_Statement (N : Node_Id) is
88 T_Name := First (Names (N));
89 while Present (T_Name) loop
92 if Is_Task_Type (Etype (T_Name))
93 or else (Ada_Version >= Ada_05
94 and then Ekind (Etype (T_Name)) = E_Class_Wide_Type
95 and then Is_Interface (Etype (T_Name))
96 and then Is_Task_Interface (Etype (T_Name)))
100 if Ada_Version >= Ada_05 then
101 Error_Msg_N ("expect task name or task interface class-wide "
102 & "object for ABORT", T_Name);
104 Error_Msg_N ("expect task name for ABORT", T_Name);
113 Check_Restriction (No_Abort_Statements, N);
114 Check_Potentially_Blocking_Operation (N);
115 end Analyze_Abort_Statement;
117 --------------------------------
118 -- Analyze_Accept_Alternative --
119 --------------------------------
121 procedure Analyze_Accept_Alternative (N : Node_Id) is
123 Tasking_Used := True;
125 if Present (Pragmas_Before (N)) then
126 Analyze_List (Pragmas_Before (N));
129 if Present (Condition (N)) then
130 Analyze_And_Resolve (Condition (N), Any_Boolean);
133 Analyze (Accept_Statement (N));
135 if Is_Non_Empty_List (Statements (N)) then
136 Analyze_Statements (Statements (N));
138 end Analyze_Accept_Alternative;
140 ------------------------------
141 -- Analyze_Accept_Statement --
142 ------------------------------
144 procedure Analyze_Accept_Statement (N : Node_Id) is
145 Nam : constant Entity_Id := Entry_Direct_Name (N);
146 Formals : constant List_Id := Parameter_Specifications (N);
147 Index : constant Node_Id := Entry_Index (N);
148 Stats : constant Node_Id := Handled_Statement_Sequence (N);
149 Accept_Id : Entity_Id;
150 Entry_Nam : Entity_Id;
153 Task_Nam : Entity_Id;
155 -----------------------
156 -- Actual_Index_Type --
157 -----------------------
159 function Actual_Index_Type (E : Entity_Id) return Entity_Id;
160 -- If the bounds of an entry family depend on task discriminants, create
161 -- a new index type where a discriminant is replaced by the local
162 -- variable that renames it in the task body.
164 function Actual_Index_Type (E : Entity_Id) return Entity_Id is
165 Typ : constant Entity_Id := Entry_Index_Type (E);
166 Lo : constant Node_Id := Type_Low_Bound (Typ);
167 Hi : constant Node_Id := Type_High_Bound (Typ);
170 function Actual_Discriminant_Ref (Bound : Node_Id) return Node_Id;
171 -- If bound is discriminant reference, replace with corresponding
172 -- local variable of the same name.
174 -----------------------------
175 -- Actual_Discriminant_Ref --
176 -----------------------------
178 function Actual_Discriminant_Ref (Bound : Node_Id) return Node_Id is
179 Typ : constant Entity_Id := Etype (Bound);
182 if not Is_Entity_Name (Bound)
183 or else Ekind (Entity (Bound)) /= E_Discriminant
187 Ref := Make_Identifier (Sloc (N), Chars (Entity (Bound)));
192 end Actual_Discriminant_Ref;
194 -- Start of processing for Actual_Index_Type
197 if not Has_Discriminants (Task_Nam)
198 or else (not Is_Entity_Name (Lo)
199 and then not Is_Entity_Name (Hi))
201 return Entry_Index_Type (E);
203 New_T := Create_Itype (Ekind (Typ), N);
204 Set_Etype (New_T, Base_Type (Typ));
205 Set_Size_Info (New_T, Typ);
206 Set_RM_Size (New_T, RM_Size (Typ));
207 Set_Scalar_Range (New_T,
208 Make_Range (Sloc (N),
209 Low_Bound => Actual_Discriminant_Ref (Lo),
210 High_Bound => Actual_Discriminant_Ref (Hi)));
214 end Actual_Index_Type;
216 -- Start of processing for Analyze_Accept_Statement
219 Tasking_Used := True;
221 -- Entry name is initialized to Any_Id. It should get reset to the
222 -- matching entry entity. An error is signalled if it is not reset.
226 for J in reverse 0 .. Scope_Stack.Last loop
227 Task_Nam := Scope_Stack.Table (J).Entity;
228 exit when Ekind (Etype (Task_Nam)) = E_Task_Type;
229 Kind := Ekind (Task_Nam);
231 if Kind /= E_Block and then Kind /= E_Loop
232 and then not Is_Entry (Task_Nam)
234 Error_Msg_N ("enclosing body of accept must be a task", N);
239 if Ekind (Etype (Task_Nam)) /= E_Task_Type then
240 Error_Msg_N ("invalid context for accept statement", N);
244 -- In order to process the parameters, we create a defining
245 -- identifier that can be used as the name of the scope. The
246 -- name of the accept statement itself is not a defining identifier,
247 -- and we cannot use its name directly because the task may have
248 -- any number of accept statements for the same entry.
250 if Present (Index) then
251 Accept_Id := New_Internal_Entity
252 (E_Entry_Family, Current_Scope, Sloc (N), 'E');
254 Accept_Id := New_Internal_Entity
255 (E_Entry, Current_Scope, Sloc (N), 'E');
258 Set_Etype (Accept_Id, Standard_Void_Type);
259 Set_Accept_Address (Accept_Id, New_Elmt_List);
261 if Present (Formals) then
262 New_Scope (Accept_Id);
263 Process_Formals (Formals, N);
264 Create_Extra_Formals (Accept_Id);
268 -- We set the default expressions processed flag because we don't need
269 -- default expression functions. This is really more like body entity
270 -- than a spec entity anyway.
272 Set_Default_Expressions_Processed (Accept_Id);
274 E := First_Entity (Etype (Task_Nam));
275 while Present (E) loop
276 if Chars (E) = Chars (Nam)
277 and then (Ekind (E) = Ekind (Accept_Id))
278 and then Type_Conformant (Accept_Id, E)
287 if Entry_Nam = Any_Id then
288 Error_Msg_N ("no entry declaration matches accept statement", N);
291 Set_Entity (Nam, Entry_Nam);
292 Generate_Reference (Entry_Nam, Nam, 'b', Set_Ref => False);
293 Style.Check_Identifier (Nam, Entry_Nam);
296 -- Verify that the entry is not hidden by a procedure declared in the
297 -- current block (pathological but possible).
299 if Current_Scope /= Task_Nam then
304 E1 := First_Entity (Current_Scope);
305 while Present (E1) loop
306 if Ekind (E1) = E_Procedure
307 and then Chars (E1) = Chars (Entry_Nam)
308 and then Type_Conformant (E1, Entry_Nam)
310 Error_Msg_N ("entry name is not visible", N);
318 Set_Convention (Accept_Id, Convention (Entry_Nam));
319 Check_Fully_Conformant (Accept_Id, Entry_Nam, N);
321 for J in reverse 0 .. Scope_Stack.Last loop
322 exit when Task_Nam = Scope_Stack.Table (J).Entity;
324 if Entry_Nam = Scope_Stack.Table (J).Entity then
325 Error_Msg_N ("duplicate accept statement for same entry", N);
336 when N_Task_Body | N_Compilation_Unit =>
338 when N_Asynchronous_Select =>
339 Error_Msg_N ("accept statements are not allowed within" &
340 " an asynchronous select inner" &
341 " to the enclosing task body", N);
349 if Ekind (E) = E_Entry_Family then
351 Error_Msg_N ("missing entry index in accept for entry family", N);
353 Analyze_And_Resolve (Index, Entry_Index_Type (E));
354 Apply_Range_Check (Index, Actual_Index_Type (E));
357 elsif Present (Index) then
358 Error_Msg_N ("invalid entry index in accept for simple entry", N);
361 -- If label declarations present, analyze them. They are declared in the
362 -- enclosing task, but their enclosing scope is the entry itself, so
363 -- that goto's to the label are recognized as local to the accept.
365 if Present (Declarations (N)) then
371 Decl := First (Declarations (N));
372 while Present (Decl) loop
376 (Nkind (Decl) = N_Implicit_Label_Declaration);
378 Id := Defining_Identifier (Decl);
379 Set_Enclosing_Scope (Id, Entry_Nam);
385 -- If statements are present, they must be analyzed in the context of
386 -- the entry, so that references to formals are correctly resolved. We
387 -- also have to add the declarations that are required by the expansion
388 -- of the accept statement in this case if expansion active.
390 -- In the case of a select alternative of a selective accept, the
391 -- expander references the address declaration even if there is no
394 -- We also need to create the renaming declarations for the local
395 -- variables that will replace references to the formals within the
398 Exp_Ch9.Expand_Accept_Declarations (N, Entry_Nam);
400 -- Set Never_Set_In_Source and clear Is_True_Constant/Current_Value
401 -- fields on all entry formals (this loop ignores all other entities).
402 -- Reset Referenced and Has_Pragma_Unreferenced as well, so that we can
403 -- post accurate warnings on each accept statement for the same entry.
405 E := First_Entity (Entry_Nam);
406 while Present (E) loop
407 if Is_Formal (E) then
408 Set_Never_Set_In_Source (E, True);
409 Set_Is_True_Constant (E, False);
410 Set_Current_Value (E, Empty);
411 Set_Referenced (E, False);
412 Set_Has_Pragma_Unreferenced (E, False);
418 -- Analyze statements if present
420 if Present (Stats) then
421 New_Scope (Entry_Nam);
422 Install_Declarations (Entry_Nam);
424 Set_Actual_Subtypes (N, Current_Scope);
427 Process_End_Label (Handled_Statement_Sequence (N), 't', Entry_Nam);
431 -- Some warning checks
433 Check_Potentially_Blocking_Operation (N);
434 Check_References (Entry_Nam, N);
435 Set_Entry_Accepted (Entry_Nam);
436 end Analyze_Accept_Statement;
438 ---------------------------------
439 -- Analyze_Asynchronous_Select --
440 ---------------------------------
442 procedure Analyze_Asynchronous_Select (N : Node_Id) is
447 Tasking_Used := True;
448 Check_Restriction (Max_Asynchronous_Select_Nesting, N);
449 Check_Restriction (No_Select_Statements, N);
451 if Ada_Version >= Ada_05 then
452 Trigger := Triggering_Statement (Triggering_Alternative (N));
456 -- The trigger is a dispatching procedure. Postpone the analysis of
457 -- the triggering and abortable statements until the expansion of
458 -- this asynchronous select in Expand_N_Asynchronous_Select. This
459 -- action is required since otherwise we would get a gigi abort from
460 -- the code replication in Expand_N_Asynchronous_Select of an already
461 -- analyzed statement list.
464 and then Nkind (Trigger) = N_Procedure_Call_Statement
465 and then Present (Parameter_Associations (Trigger))
467 Param := First (Parameter_Associations (Trigger));
469 if Is_Controlling_Actual (Param)
470 and then Is_Interface (Etype (Param))
472 if Is_Limited_Record (Etype (Param)) then
476 ("dispatching operation of limited or synchronized " &
477 "interface required ('R'M 9.7.2(3))!", N);
483 -- Analyze the statements. We analyze statements in the abortable part,
484 -- because this is the section that is executed first, and that way our
485 -- remembering of saved values and checks is accurate.
487 Analyze_Statements (Statements (Abortable_Part (N)));
488 Analyze (Triggering_Alternative (N));
489 end Analyze_Asynchronous_Select;
491 ------------------------------------
492 -- Analyze_Conditional_Entry_Call --
493 ------------------------------------
495 procedure Analyze_Conditional_Entry_Call (N : Node_Id) is
497 Check_Restriction (No_Select_Statements, N);
498 Tasking_Used := True;
499 Analyze (Entry_Call_Alternative (N));
501 if List_Length (Else_Statements (N)) = 1
502 and then Nkind (First (Else_Statements (N))) in N_Delay_Statement
505 ("suspicious form of conditional entry call?", N);
507 ("\`SELECT OR` may be intended rather than `SELECT ELSE`", N);
510 Analyze_Statements (Else_Statements (N));
511 end Analyze_Conditional_Entry_Call;
513 --------------------------------
514 -- Analyze_Delay_Alternative --
515 --------------------------------
517 procedure Analyze_Delay_Alternative (N : Node_Id) is
522 Tasking_Used := True;
523 Check_Restriction (No_Delay, N);
525 if Present (Pragmas_Before (N)) then
526 Analyze_List (Pragmas_Before (N));
529 if Nkind (Parent (N)) = N_Selective_Accept
530 or else Nkind (Parent (N)) = N_Timed_Entry_Call
532 Expr := Expression (Delay_Statement (N));
534 -- Defer full analysis until the statement is expanded, to insure
535 -- that generated code does not move past the guard. The delay
536 -- expression is only evaluated if the guard is open.
538 if Nkind (Delay_Statement (N)) = N_Delay_Relative_Statement then
539 Pre_Analyze_And_Resolve (Expr, Standard_Duration);
541 Pre_Analyze_And_Resolve (Expr);
544 Typ := First_Subtype (Etype (Expr));
546 if Nkind (Delay_Statement (N)) = N_Delay_Until_Statement
547 and then not Is_RTE (Typ, RO_CA_Time)
548 and then not Is_RTE (Typ, RO_RT_Time)
550 Error_Msg_N ("expect Time types for `DELAY UNTIL`", Expr);
553 Check_Restriction (No_Fixed_Point, Expr);
556 Analyze (Delay_Statement (N));
559 if Present (Condition (N)) then
560 Analyze_And_Resolve (Condition (N), Any_Boolean);
563 if Is_Non_Empty_List (Statements (N)) then
564 Analyze_Statements (Statements (N));
566 end Analyze_Delay_Alternative;
568 ----------------------------
569 -- Analyze_Delay_Relative --
570 ----------------------------
572 procedure Analyze_Delay_Relative (N : Node_Id) is
573 E : constant Node_Id := Expression (N);
576 Check_Restriction (No_Relative_Delay, N);
577 Tasking_Used := True;
578 Check_Restriction (No_Delay, N);
579 Check_Potentially_Blocking_Operation (N);
580 Analyze_And_Resolve (E, Standard_Duration);
581 Check_Restriction (No_Fixed_Point, E);
582 end Analyze_Delay_Relative;
584 -------------------------
585 -- Analyze_Delay_Until --
586 -------------------------
588 procedure Analyze_Delay_Until (N : Node_Id) is
589 E : constant Node_Id := Expression (N);
593 Tasking_Used := True;
594 Check_Restriction (No_Delay, N);
595 Check_Potentially_Blocking_Operation (N);
597 Typ := First_Subtype (Etype (E));
599 if not Is_RTE (Typ, RO_CA_Time) and then
600 not Is_RTE (Typ, RO_RT_Time)
602 Error_Msg_N ("expect Time types for `DELAY UNTIL`", E);
604 end Analyze_Delay_Until;
606 ------------------------
607 -- Analyze_Entry_Body --
608 ------------------------
610 procedure Analyze_Entry_Body (N : Node_Id) is
611 Id : constant Entity_Id := Defining_Identifier (N);
612 Decls : constant List_Id := Declarations (N);
613 Stats : constant Node_Id := Handled_Statement_Sequence (N);
614 Formals : constant Node_Id := Entry_Body_Formal_Part (N);
615 P_Type : constant Entity_Id := Current_Scope;
616 Entry_Name : Entity_Id;
620 Tasking_Used := True;
622 -- Entry_Name is initialized to Any_Id. It should get reset to the
623 -- matching entry entity. An error is signalled if it is not reset
625 Entry_Name := Any_Id;
629 if Present (Entry_Index_Specification (Formals)) then
630 Set_Ekind (Id, E_Entry_Family);
632 Set_Ekind (Id, E_Entry);
635 Set_Scope (Id, Current_Scope);
636 Set_Etype (Id, Standard_Void_Type);
637 Set_Accept_Address (Id, New_Elmt_List);
639 E := First_Entity (P_Type);
640 while Present (E) loop
641 if Chars (E) = Chars (Id)
642 and then (Ekind (E) = Ekind (Id))
643 and then Type_Conformant (Id, E)
646 Set_Convention (Id, Convention (E));
647 Set_Corresponding_Body (Parent (Entry_Name), Id);
648 Check_Fully_Conformant (Id, E, N);
650 if Ekind (Id) = E_Entry_Family then
651 if not Fully_Conformant_Discrete_Subtypes (
652 Discrete_Subtype_Definition (Parent (E)),
653 Discrete_Subtype_Definition
654 (Entry_Index_Specification (Formals)))
657 ("index not fully conformant with previous declaration",
658 Discrete_Subtype_Definition
659 (Entry_Index_Specification (Formals)));
662 -- The elaboration of the entry body does not recompute the
663 -- bounds of the index, which may have side effects. Inherit
664 -- the bounds from the entry declaration. This is critical
665 -- if the entry has a per-object constraint. If a bound is
666 -- given by a discriminant, it must be reanalyzed in order
667 -- to capture the discriminal of the current entry, rather
668 -- than that of the protected type.
671 Index_Spec : constant Node_Id :=
672 Entry_Index_Specification (Formals);
674 Def : constant Node_Id :=
676 (Discrete_Subtype_Definition (Parent (E)));
681 (Discrete_Subtype_Definition (Index_Spec))) = N_Range
683 Set_Etype (Def, Empty);
684 Set_Analyzed (Def, False);
686 -- Keep the original subtree to ensure a properly
687 -- formed tree (e.g. for ASIS use).
690 (Discrete_Subtype_Definition (Index_Spec), Def);
692 Set_Analyzed (Low_Bound (Def), False);
693 Set_Analyzed (High_Bound (Def), False);
695 if Denotes_Discriminant (Low_Bound (Def)) then
696 Set_Entity (Low_Bound (Def), Empty);
699 if Denotes_Discriminant (High_Bound (Def)) then
700 Set_Entity (High_Bound (Def), Empty);
704 Make_Index (Def, Index_Spec);
706 (Defining_Identifier (Index_Spec), Etype (Def));
718 if Entry_Name = Any_Id then
719 Error_Msg_N ("no entry declaration matches entry body", N);
722 elsif Has_Completion (Entry_Name) then
723 Error_Msg_N ("duplicate entry body", N);
727 Set_Has_Completion (Entry_Name);
728 Generate_Reference (Entry_Name, Id, 'b', Set_Ref => False);
729 Style.Check_Identifier (Id, Entry_Name);
732 Exp_Ch9.Expand_Entry_Barrier (N, Entry_Name);
733 New_Scope (Entry_Name);
735 Exp_Ch9.Expand_Entry_Body_Declarations (N);
736 Install_Declarations (Entry_Name);
737 Set_Actual_Subtypes (N, Current_Scope);
739 -- The entity for the protected subprogram corresponding to the entry
740 -- has been created. We retain the name of this entity in the entry
741 -- body, for use when the corresponding subprogram body is created.
742 -- Note that entry bodies have no corresponding_spec, and there is no
743 -- easy link back in the tree between the entry body and the entity for
744 -- the entry itself, which is why we must propagate some attributes
745 -- explicitly from spec to body.
747 Set_Protected_Body_Subprogram
748 (Id, Protected_Body_Subprogram (Entry_Name));
750 Set_Entry_Parameters_Type
751 (Id, Entry_Parameters_Type (Entry_Name));
753 if Present (Decls) then
754 Analyze_Declarations (Decls);
757 if Present (Stats) then
761 -- Check for unreferenced variables etc. Before the Check_References
762 -- call, we transfer Never_Set_In_Source and Referenced flags from
763 -- parameters in the spec to the corresponding entities in the body,
764 -- since we want the warnings on the body entities. Note that we do
765 -- not have to transfer Referenced_As_LHS, since that flag can only
766 -- be set for simple variables.
768 -- At the same time, we set the flags on the spec entities to suppress
769 -- any warnings on the spec formals, since we also scan the spec.
770 -- Finally, we propagate the Entry_Component attribute to the body
771 -- formals, for use in the renaming declarations created later for the
772 -- formals (see exp_ch9.Add_Formal_Renamings).
779 E1 := First_Entity (Entry_Name);
780 while Present (E1) loop
781 E2 := First_Entity (Id);
782 while Present (E2) loop
783 exit when Chars (E1) = Chars (E2);
787 -- If no matching body entity, then we already had a detected
788 -- error of some kind, so just forget about worrying about these
795 if Ekind (E1) = E_Out_Parameter then
796 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
797 Set_Never_Set_In_Source (E1, False);
800 Set_Referenced (E2, Referenced (E1));
802 Set_Entry_Component (E2, Entry_Component (E1));
808 Check_References (Id);
811 -- We still need to check references for the spec, since objects
812 -- declared in the body are chained (in the First_Entity sense) to
813 -- the spec rather than the body in the case of entries.
815 Check_References (Entry_Name);
817 -- Process the end label, and terminate the scope
819 Process_End_Label (Handled_Statement_Sequence (N), 't', Entry_Name);
822 -- If this is an entry family, remove the loop created to provide
823 -- a scope for the entry index.
825 if Ekind (Id) = E_Entry_Family
826 and then Present (Entry_Index_Specification (Formals))
830 end Analyze_Entry_Body;
832 ------------------------------------
833 -- Analyze_Entry_Body_Formal_Part --
834 ------------------------------------
836 procedure Analyze_Entry_Body_Formal_Part (N : Node_Id) is
837 Id : constant Entity_Id := Defining_Identifier (Parent (N));
838 Index : constant Node_Id := Entry_Index_Specification (N);
839 Formals : constant List_Id := Parameter_Specifications (N);
842 Tasking_Used := True;
844 if Present (Index) then
848 if Present (Formals) then
849 Set_Scope (Id, Current_Scope);
851 Process_Formals (Formals, Parent (N));
854 end Analyze_Entry_Body_Formal_Part;
856 ------------------------------------
857 -- Analyze_Entry_Call_Alternative --
858 ------------------------------------
860 procedure Analyze_Entry_Call_Alternative (N : Node_Id) is
861 Call : constant Node_Id := Entry_Call_Statement (N);
864 Tasking_Used := True;
866 if Present (Pragmas_Before (N)) then
867 Analyze_List (Pragmas_Before (N));
870 if Nkind (Call) = N_Attribute_Reference then
872 -- Possibly a stream attribute, but definitely illegal. Other
873 -- illegalitles, such as procedure calls, are diagnosed after
876 Error_Msg_N ("entry call alternative requires an entry call", Call);
882 if Is_Non_Empty_List (Statements (N)) then
883 Analyze_Statements (Statements (N));
885 end Analyze_Entry_Call_Alternative;
887 -------------------------------
888 -- Analyze_Entry_Declaration --
889 -------------------------------
891 procedure Analyze_Entry_Declaration (N : Node_Id) is
892 Formals : constant List_Id := Parameter_Specifications (N);
893 Id : constant Entity_Id := Defining_Identifier (N);
894 D_Sdef : constant Node_Id := Discrete_Subtype_Definition (N);
897 Generate_Definition (Id);
898 Tasking_Used := True;
901 Set_Ekind (Id, E_Entry);
904 Set_Ekind (Id, E_Entry_Family);
906 Make_Index (D_Sdef, N, Id);
909 Set_Etype (Id, Standard_Void_Type);
910 Set_Convention (Id, Convention_Entry);
911 Set_Accept_Address (Id, New_Elmt_List);
913 if Present (Formals) then
914 Set_Scope (Id, Current_Scope);
916 Process_Formals (Formals, N);
917 Create_Extra_Formals (Id);
921 if Ekind (Id) = E_Entry then
922 New_Overloaded_Entity (Id);
925 Generate_Reference_To_Formals (Id);
926 end Analyze_Entry_Declaration;
928 ---------------------------------------
929 -- Analyze_Entry_Index_Specification --
930 ---------------------------------------
932 -- The Defining_Identifier of the entry index specification is local to the
933 -- entry body, but it must be available in the entry barrier which is
934 -- evaluated outside of the entry body. The index is eventually renamed as
935 -- a run-time object, so is visibility is strictly a front-end concern. In
936 -- order to make it available to the barrier, we create an additional
937 -- scope, as for a loop, whose only declaration is the index name. This
938 -- loop is not attached to the tree and does not appear as an entity local
939 -- to the protected type, so its existence need only be knwown to routines
940 -- that process entry families.
942 procedure Analyze_Entry_Index_Specification (N : Node_Id) is
943 Iden : constant Node_Id := Defining_Identifier (N);
944 Def : constant Node_Id := Discrete_Subtype_Definition (N);
945 Loop_Id : constant Entity_Id :=
946 Make_Defining_Identifier (Sloc (N),
947 Chars => New_Internal_Name ('L'));
950 Tasking_Used := True;
953 -- There is no elaboration of the entry index specification. Therefore,
954 -- if the index is a range, it is not resolved and expanded, but the
955 -- bounds are inherited from the entry declaration, and reanalyzed.
956 -- See Analyze_Entry_Body.
958 if Nkind (Def) /= N_Range then
962 Set_Ekind (Loop_Id, E_Loop);
963 Set_Scope (Loop_Id, Current_Scope);
966 Set_Ekind (Iden, E_Entry_Index_Parameter);
967 Set_Etype (Iden, Etype (Def));
968 end Analyze_Entry_Index_Specification;
970 ----------------------------
971 -- Analyze_Protected_Body --
972 ----------------------------
974 procedure Analyze_Protected_Body (N : Node_Id) is
975 Body_Id : constant Entity_Id := Defining_Identifier (N);
979 -- This is initially the entity of the protected object or protected
980 -- type involved, but is replaced by the protected type always in the
981 -- case of a single protected declaration, since this is the proper
985 -- This is the entity of the protected object or protected type
986 -- involved, and is the entity used for cross-reference purposes
987 -- (it differs from Spec_Id in the case of a single protected
988 -- object, since Spec_Id is set to the protected type in this case).
991 Tasking_Used := True;
992 Set_Ekind (Body_Id, E_Protected_Body);
993 Spec_Id := Find_Concurrent_Spec (Body_Id);
996 and then Ekind (Spec_Id) = E_Protected_Type
1000 elsif Present (Spec_Id)
1001 and then Ekind (Etype (Spec_Id)) = E_Protected_Type
1002 and then not Comes_From_Source (Etype (Spec_Id))
1007 Error_Msg_N ("missing specification for protected body", Body_Id);
1012 Generate_Reference (Ref_Id, Body_Id, 'b', Set_Ref => False);
1013 Style.Check_Identifier (Body_Id, Spec_Id);
1015 -- The declarations are always attached to the type
1017 if Ekind (Spec_Id) /= E_Protected_Type then
1018 Spec_Id := Etype (Spec_Id);
1021 New_Scope (Spec_Id);
1022 Set_Corresponding_Spec (N, Spec_Id);
1023 Set_Corresponding_Body (Parent (Spec_Id), Body_Id);
1024 Set_Has_Completion (Spec_Id);
1025 Install_Declarations (Spec_Id);
1027 Exp_Ch9.Expand_Protected_Body_Declarations (N, Spec_Id);
1029 Last_E := Last_Entity (Spec_Id);
1031 Analyze_Declarations (Declarations (N));
1033 -- For visibility purposes, all entities in the body are private. Set
1034 -- First_Private_Entity accordingly, if there was no private part in the
1035 -- protected declaration.
1037 if No (First_Private_Entity (Spec_Id)) then
1038 if Present (Last_E) then
1039 Set_First_Private_Entity (Spec_Id, Next_Entity (Last_E));
1041 Set_First_Private_Entity (Spec_Id, First_Entity (Spec_Id));
1045 Check_Completion (Body_Id);
1046 Check_References (Spec_Id);
1047 Process_End_Label (N, 't', Ref_Id);
1049 end Analyze_Protected_Body;
1051 ----------------------------------
1052 -- Analyze_Protected_Definition --
1053 ----------------------------------
1055 procedure Analyze_Protected_Definition (N : Node_Id) is
1060 Tasking_Used := True;
1061 Analyze_Declarations (Visible_Declarations (N));
1063 if Present (Private_Declarations (N))
1064 and then not Is_Empty_List (Private_Declarations (N))
1066 L := Last_Entity (Current_Scope);
1067 Analyze_Declarations (Private_Declarations (N));
1070 Set_First_Private_Entity (Current_Scope, Next_Entity (L));
1072 Set_First_Private_Entity (Current_Scope,
1073 First_Entity (Current_Scope));
1077 E := First_Entity (Current_Scope);
1078 while Present (E) loop
1079 if Ekind (E) = E_Function
1080 or else Ekind (E) = E_Procedure
1082 Set_Convention (E, Convention_Protected);
1084 elsif Is_Task_Type (Etype (E))
1085 or else Has_Task (Etype (E))
1087 Set_Has_Task (Current_Scope);
1093 Check_Max_Entries (N, Max_Protected_Entries);
1094 Process_End_Label (N, 'e', Current_Scope);
1095 end Analyze_Protected_Definition;
1097 ----------------------------
1098 -- Analyze_Protected_Type --
1099 ----------------------------
1101 procedure Analyze_Protected_Type (N : Node_Id) is
1104 Def_Id : constant Entity_Id := Defining_Identifier (N);
1106 Iface_Typ : Entity_Id;
1109 if No_Run_Time_Mode then
1110 Error_Msg_CRT ("protected type", N);
1114 Tasking_Used := True;
1115 Check_Restriction (No_Protected_Types, N);
1117 T := Find_Type_Name (N);
1119 if Ekind (T) = E_Incomplete_Type then
1121 Set_Completion_Referenced (T);
1124 Set_Ekind (T, E_Protected_Type);
1125 Set_Is_First_Subtype (T, True);
1126 Init_Size_Align (T);
1128 Set_Has_Delayed_Freeze (T, True);
1129 Set_Stored_Constraint (T, No_Elist);
1132 -- Ada 2005 (AI-345)
1134 if Present (Interface_List (N)) then
1135 Set_Is_Tagged_Type (T);
1137 Iface := First (Interface_List (N));
1138 while Present (Iface) loop
1139 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
1141 if not Is_Interface (Iface_Typ) then
1142 Error_Msg_NE ("(Ada 2005) & must be an interface",
1146 -- Ada 2005 (AI-251): "The declaration of a specific descendant
1147 -- of an interface type freezes the interface type" RM 13.14.
1149 Freeze_Before (N, Etype (Iface));
1151 -- Ada 2005 (AI-345): Protected types can only implement
1152 -- limited, synchronized or protected interfaces.
1154 if Is_Limited_Interface (Iface_Typ)
1155 or else Is_Protected_Interface (Iface_Typ)
1156 or else Is_Synchronized_Interface (Iface_Typ)
1160 elsif Is_Task_Interface (Iface_Typ) then
1161 Error_Msg_N ("(Ada 2005) protected type cannot implement a "
1162 & "task interface", Iface);
1165 Error_Msg_N ("(Ada 2005) protected type cannot implement a "
1166 & "non-limited interface", Iface);
1173 -- If this is the full-declaration associated with a private
1174 -- declaration that implement interfaces, then the private type
1175 -- declaration must be limited.
1177 if Has_Private_Declaration (T) then
1182 E := First_Entity (Scope (T));
1184 pragma Assert (Present (E));
1186 if Is_Type (E) and then Present (Full_View (E)) then
1187 exit when Full_View (E) = T;
1193 if not Is_Limited_Record (E) then
1194 Error_Msg_Sloc := Sloc (E);
1196 ("(Ada 2005) private type declaration # must be limited",
1203 if Present (Discriminant_Specifications (N)) then
1204 if Has_Discriminants (T) then
1206 -- Install discriminants. Also, verify conformance of
1207 -- discriminants of previous and current view. ???
1209 Install_Declarations (T);
1211 Process_Discriminants (N);
1215 Set_Is_Constrained (T, not Has_Discriminants (T));
1217 Analyze (Protected_Definition (N));
1219 -- Protected types with entries are controlled (because of the
1220 -- Protection component if nothing else), same for any protected type
1221 -- with interrupt handlers. Note that we need to analyze the protected
1222 -- definition to set Has_Entries and such.
1224 if (Abort_Allowed or else Restriction_Active (No_Entry_Queue) = False
1225 or else Number_Entries (T) > 1)
1228 or else Has_Interrupt_Handler (T)
1229 or else Has_Attach_Handler (T))
1231 Set_Has_Controlled_Component (T, True);
1234 -- The Ekind of components is E_Void during analysis to detect illegal
1235 -- uses. Now it can be set correctly.
1237 E := First_Entity (Current_Scope);
1238 while Present (E) loop
1239 if Ekind (E) = E_Void then
1240 Set_Ekind (E, E_Component);
1241 Init_Component_Location (E);
1249 -- Case of a completion of a private declaration
1252 and then Is_Private_Type (Def_Id)
1254 -- Deal with preelaborable initialization. Note that this processing
1255 -- is done by Process_Full_View, but as can be seen below, in this
1256 -- case the call to Process_Full_View is skipped if any serious
1257 -- errors have occurred, and we don't want to lose this check.
1259 if Known_To_Have_Preelab_Init (Def_Id) then
1260 Set_Must_Have_Preelab_Init (T);
1263 -- Create corresponding record now, because some private dependents
1264 -- may be subtypes of the partial view. Skip if errors are present,
1265 -- to prevent cascaded messages.
1267 if Serious_Errors_Detected = 0 then
1268 Exp_Ch9.Expand_N_Protected_Type_Declaration (N);
1269 Process_Full_View (N, T, Def_Id);
1272 end Analyze_Protected_Type;
1274 ---------------------
1275 -- Analyze_Requeue --
1276 ---------------------
1278 procedure Analyze_Requeue (N : Node_Id) is
1279 Count : Natural := 0;
1280 Entry_Name : Node_Id := Name (N);
1281 Entry_Id : Entity_Id;
1284 Enclosing : Entity_Id;
1285 Target_Obj : Node_Id := Empty;
1286 Req_Scope : Entity_Id;
1287 Outer_Ent : Entity_Id;
1290 Check_Restriction (No_Requeue_Statements, N);
1291 Check_Unreachable_Code (N);
1292 Tasking_Used := True;
1295 for J in reverse 0 .. Scope_Stack.Last loop
1296 Enclosing := Scope_Stack.Table (J).Entity;
1297 exit when Is_Entry (Enclosing);
1299 if Ekind (Enclosing) /= E_Block
1300 and then Ekind (Enclosing) /= E_Loop
1302 Error_Msg_N ("requeue must appear within accept or entry body", N);
1307 Analyze (Entry_Name);
1309 if Etype (Entry_Name) = Any_Type then
1313 if Nkind (Entry_Name) = N_Selected_Component then
1314 Target_Obj := Prefix (Entry_Name);
1315 Entry_Name := Selector_Name (Entry_Name);
1318 -- If an explicit target object is given then we have to check the
1319 -- restrictions of 9.5.4(6).
1321 if Present (Target_Obj) then
1323 -- Locate containing concurrent unit and determine enclosing entry
1324 -- body or outermost enclosing accept statement within the unit.
1327 for S in reverse 0 .. Scope_Stack.Last loop
1328 Req_Scope := Scope_Stack.Table (S).Entity;
1330 exit when Ekind (Req_Scope) in Task_Kind
1331 or else Ekind (Req_Scope) in Protected_Kind;
1333 if Is_Entry (Req_Scope) then
1334 Outer_Ent := Req_Scope;
1338 pragma Assert (Present (Outer_Ent));
1340 -- Check that the accessibility level of the target object is not
1341 -- greater or equal to the outermost enclosing accept statement (or
1342 -- entry body) unless it is a parameter of the innermost enclosing
1343 -- accept statement (or entry body).
1345 if Object_Access_Level (Target_Obj) >= Scope_Depth (Outer_Ent)
1347 (not Is_Entity_Name (Target_Obj)
1348 or else Ekind (Entity (Target_Obj)) not in Formal_Kind
1349 or else Enclosing /= Scope (Entity (Target_Obj)))
1352 ("target object has invalid level for requeue", Target_Obj);
1356 -- Overloaded case, find right interpretation
1358 if Is_Overloaded (Entry_Name) then
1361 Get_First_Interp (Entry_Name, I, It);
1362 while Present (It.Nam) loop
1363 if No (First_Formal (It.Nam))
1364 or else Subtype_Conformant (Enclosing, It.Nam)
1366 -- Ada 2005 (AI-345): Since protected and task types have
1367 -- primitive entry wrappers, we only consider source entries.
1369 if Comes_From_Source (It.Nam) then
1377 Get_Next_Interp (I, It);
1381 Error_Msg_N ("no entry matches context", N);
1384 elsif Count > 1 then
1385 Error_Msg_N ("ambiguous entry name in requeue", N);
1389 Set_Is_Overloaded (Entry_Name, False);
1390 Set_Entity (Entry_Name, Entry_Id);
1393 -- Non-overloaded cases
1395 -- For the case of a reference to an element of an entry family, the
1396 -- Entry_Name is an indexed component.
1398 elsif Nkind (Entry_Name) = N_Indexed_Component then
1400 -- Requeue to an entry out of the body
1402 if Nkind (Prefix (Entry_Name)) = N_Selected_Component then
1403 Entry_Id := Entity (Selector_Name (Prefix (Entry_Name)));
1405 -- Requeue from within the body itself
1407 elsif Nkind (Prefix (Entry_Name)) = N_Identifier then
1408 Entry_Id := Entity (Prefix (Entry_Name));
1411 Error_Msg_N ("invalid entry_name specified", N);
1415 -- If we had a requeue of the form REQUEUE A (B), then the parser
1416 -- accepted it (because it could have been a requeue on an entry index.
1417 -- If A turns out not to be an entry family, then the analysis of A (B)
1418 -- turned it into a function call.
1420 elsif Nkind (Entry_Name) = N_Function_Call then
1422 ("arguments not allowed in requeue statement",
1423 First (Parameter_Associations (Entry_Name)));
1426 -- Normal case of no entry family, no argument
1429 Entry_Id := Entity (Entry_Name);
1432 -- Resolve entry, and check that it is subtype conformant with the
1433 -- enclosing construct if this construct has formals (RM 9.5.4(5)).
1435 if not Is_Entry (Entry_Id) then
1436 Error_Msg_N ("expect entry name in requeue statement", Name (N));
1437 elsif Ekind (Entry_Id) = E_Entry_Family
1438 and then Nkind (Entry_Name) /= N_Indexed_Component
1440 Error_Msg_N ("missing index for entry family component", Name (N));
1443 Resolve_Entry (Name (N));
1444 Generate_Reference (Entry_Id, Entry_Name);
1446 if Present (First_Formal (Entry_Id)) then
1447 Check_Subtype_Conformant (Enclosing, Entry_Id, Name (N));
1449 -- Processing for parameters accessed by the requeue
1455 Ent := First_Formal (Enclosing);
1456 while Present (Ent) loop
1458 -- For OUT or IN OUT parameter, the effect of the requeue is
1459 -- to assign the parameter a value on exit from the requeued
1460 -- body, so we can set it as source assigned. We also clear
1461 -- the Is_True_Constant indication. We do not need to clear
1462 -- Current_Value, since the effect of the requeue is to
1463 -- perform an unconditional goto so that any further
1464 -- references will not occur anyway.
1466 if Ekind (Ent) = E_Out_Parameter
1468 Ekind (Ent) = E_In_Out_Parameter
1470 Set_Never_Set_In_Source (Ent, False);
1471 Set_Is_True_Constant (Ent, False);
1474 -- For all parameters, the requeue acts as a reference,
1475 -- since the value of the parameter is passed to the new
1476 -- entry, so we want to suppress unreferenced warnings.
1478 Set_Referenced (Ent);
1484 end Analyze_Requeue;
1486 ------------------------------
1487 -- Analyze_Selective_Accept --
1488 ------------------------------
1490 procedure Analyze_Selective_Accept (N : Node_Id) is
1491 Alts : constant List_Id := Select_Alternatives (N);
1494 Accept_Present : Boolean := False;
1495 Terminate_Present : Boolean := False;
1496 Delay_Present : Boolean := False;
1497 Relative_Present : Boolean := False;
1498 Alt_Count : Uint := Uint_0;
1501 Check_Restriction (No_Select_Statements, N);
1502 Tasking_Used := True;
1504 -- Loop to analyze alternatives
1506 Alt := First (Alts);
1507 while Present (Alt) loop
1508 Alt_Count := Alt_Count + 1;
1511 if Nkind (Alt) = N_Delay_Alternative then
1512 if Delay_Present then
1514 if Relative_Present /=
1515 (Nkind (Delay_Statement (Alt)) = N_Delay_Relative_Statement)
1518 ("delay_until and delay_relative alternatives ", Alt);
1520 ("\cannot appear in the same selective_wait", Alt);
1524 Delay_Present := True;
1526 Nkind (Delay_Statement (Alt)) = N_Delay_Relative_Statement;
1529 elsif Nkind (Alt) = N_Terminate_Alternative then
1530 if Terminate_Present then
1531 Error_Msg_N ("only one terminate alternative allowed", N);
1533 Terminate_Present := True;
1534 Check_Restriction (No_Terminate_Alternatives, N);
1537 elsif Nkind (Alt) = N_Accept_Alternative then
1538 Accept_Present := True;
1540 -- Check for duplicate accept
1544 Stm : constant Node_Id := Accept_Statement (Alt);
1545 EDN : constant Node_Id := Entry_Direct_Name (Stm);
1549 if Nkind (EDN) = N_Identifier
1550 and then No (Condition (Alt))
1551 and then Present (Entity (EDN)) -- defend against junk
1552 and then Ekind (Entity (EDN)) = E_Entry
1554 Ent := Entity (EDN);
1556 Alt1 := First (Alts);
1557 while Alt1 /= Alt loop
1558 if Nkind (Alt1) = N_Accept_Alternative
1559 and then No (Condition (Alt1))
1562 Stm1 : constant Node_Id := Accept_Statement (Alt1);
1563 EDN1 : constant Node_Id := Entry_Direct_Name (Stm1);
1566 if Nkind (EDN1) = N_Identifier then
1567 if Entity (EDN1) = Ent then
1568 Error_Msg_Sloc := Sloc (Stm1);
1570 ("?accept duplicates one on line#", Stm);
1586 Check_Restriction (Max_Select_Alternatives, N, Alt_Count);
1587 Check_Potentially_Blocking_Operation (N);
1589 if Terminate_Present and Delay_Present then
1590 Error_Msg_N ("at most one of terminate or delay alternative", N);
1592 elsif not Accept_Present then
1594 ("select must contain at least one accept alternative", N);
1597 if Present (Else_Statements (N)) then
1598 if Terminate_Present or Delay_Present then
1599 Error_Msg_N ("else part not allowed with other alternatives", N);
1602 Analyze_Statements (Else_Statements (N));
1604 end Analyze_Selective_Accept;
1606 ------------------------------
1607 -- Analyze_Single_Protected --
1608 ------------------------------
1610 procedure Analyze_Single_Protected (N : Node_Id) is
1611 Loc : constant Source_Ptr := Sloc (N);
1612 Id : constant Node_Id := Defining_Identifier (N);
1616 O_Name : constant Entity_Id := New_Copy (Id);
1619 Generate_Definition (Id);
1620 Tasking_Used := True;
1622 -- The node is rewritten as a protected type declaration, in exact
1623 -- analogy with what is done with single tasks.
1626 Make_Defining_Identifier (Sloc (Id),
1627 New_External_Name (Chars (Id), 'T'));
1630 Make_Protected_Type_Declaration (Loc,
1631 Defining_Identifier => T,
1632 Protected_Definition => Relocate_Node (Protected_Definition (N)),
1633 Interface_List => Interface_List (N));
1636 Make_Object_Declaration (Loc,
1637 Defining_Identifier => O_Name,
1638 Object_Definition => Make_Identifier (Loc, Chars (T)));
1640 Rewrite (N, T_Decl);
1641 Insert_After (N, O_Decl);
1642 Mark_Rewrite_Insertion (O_Decl);
1644 -- Enter names of type and object before analysis, because the name of
1645 -- the object may be used in its own body.
1648 Set_Ekind (T, E_Protected_Type);
1651 Enter_Name (O_Name);
1652 Set_Ekind (O_Name, E_Variable);
1653 Set_Etype (O_Name, T);
1655 -- Instead of calling Analyze on the new node, call the proper analysis
1656 -- procedure directly. Otherwise the node would be expanded twice, with
1657 -- disastrous result.
1659 Analyze_Protected_Type (N);
1660 end Analyze_Single_Protected;
1662 -------------------------
1663 -- Analyze_Single_Task --
1664 -------------------------
1666 procedure Analyze_Single_Task (N : Node_Id) is
1667 Loc : constant Source_Ptr := Sloc (N);
1668 Id : constant Node_Id := Defining_Identifier (N);
1672 O_Name : constant Entity_Id := New_Copy (Id);
1675 Generate_Definition (Id);
1676 Tasking_Used := True;
1678 -- The node is rewritten as a task type declaration, followed by an
1679 -- object declaration of that anonymous task type.
1682 Make_Defining_Identifier (Sloc (Id),
1683 New_External_Name (Chars (Id), Suffix => "TK"));
1686 Make_Task_Type_Declaration (Loc,
1687 Defining_Identifier => T,
1688 Task_Definition => Relocate_Node (Task_Definition (N)),
1689 Interface_List => Interface_List (N));
1692 Make_Object_Declaration (Loc,
1693 Defining_Identifier => O_Name,
1694 Object_Definition => Make_Identifier (Loc, Chars (T)));
1696 Rewrite (N, T_Decl);
1697 Insert_After (N, O_Decl);
1698 Mark_Rewrite_Insertion (O_Decl);
1700 -- Enter names of type and object before analysis, because the name of
1701 -- the object may be used in its own body.
1704 Set_Ekind (T, E_Task_Type);
1707 Enter_Name (O_Name);
1708 Set_Ekind (O_Name, E_Variable);
1709 Set_Etype (O_Name, T);
1711 -- Instead of calling Analyze on the new node, call the proper analysis
1712 -- procedure directly. Otherwise the node would be expanded twice, with
1713 -- disastrous result.
1715 Analyze_Task_Type (N);
1716 end Analyze_Single_Task;
1718 -----------------------
1719 -- Analyze_Task_Body --
1720 -----------------------
1722 procedure Analyze_Task_Body (N : Node_Id) is
1723 Body_Id : constant Entity_Id := Defining_Identifier (N);
1726 Spec_Id : Entity_Id;
1727 -- This is initially the entity of the task or task type involved, but
1728 -- is replaced by the task type always in the case of a single task
1729 -- declaration, since this is the proper scope to be used.
1732 -- This is the entity of the task or task type, and is the entity used
1733 -- for cross-reference purposes (it differs from Spec_Id in the case of
1734 -- a single task, since Spec_Id is set to the task type)
1737 Tasking_Used := True;
1738 Set_Ekind (Body_Id, E_Task_Body);
1739 Set_Scope (Body_Id, Current_Scope);
1740 Spec_Id := Find_Concurrent_Spec (Body_Id);
1742 -- The spec is either a task type declaration, or a single task
1743 -- declaration for which we have created an anonymous type.
1745 if Present (Spec_Id)
1746 and then Ekind (Spec_Id) = E_Task_Type
1750 elsif Present (Spec_Id)
1751 and then Ekind (Etype (Spec_Id)) = E_Task_Type
1752 and then not Comes_From_Source (Etype (Spec_Id))
1757 Error_Msg_N ("missing specification for task body", Body_Id);
1761 if Has_Completion (Spec_Id)
1762 and then Present (Corresponding_Body (Parent (Spec_Id)))
1764 if Nkind (Parent (Spec_Id)) = N_Task_Type_Declaration then
1765 Error_Msg_NE ("duplicate body for task type&", N, Spec_Id);
1768 Error_Msg_NE ("duplicate body for task&", N, Spec_Id);
1773 Generate_Reference (Ref_Id, Body_Id, 'b', Set_Ref => False);
1774 Style.Check_Identifier (Body_Id, Spec_Id);
1776 -- Deal with case of body of single task (anonymous type was created)
1778 if Ekind (Spec_Id) = E_Variable then
1779 Spec_Id := Etype (Spec_Id);
1782 New_Scope (Spec_Id);
1783 Set_Corresponding_Spec (N, Spec_Id);
1784 Set_Corresponding_Body (Parent (Spec_Id), Body_Id);
1785 Set_Has_Completion (Spec_Id);
1786 Install_Declarations (Spec_Id);
1787 Last_E := Last_Entity (Spec_Id);
1789 Analyze_Declarations (Declarations (N));
1791 -- For visibility purposes, all entities in the body are private. Set
1792 -- First_Private_Entity accordingly, if there was no private part in the
1793 -- protected declaration.
1795 if No (First_Private_Entity (Spec_Id)) then
1796 if Present (Last_E) then
1797 Set_First_Private_Entity (Spec_Id, Next_Entity (Last_E));
1799 Set_First_Private_Entity (Spec_Id, First_Entity (Spec_Id));
1803 Analyze (Handled_Statement_Sequence (N));
1804 Check_Completion (Body_Id);
1805 Check_References (Body_Id);
1806 Check_References (Spec_Id);
1808 -- Check for entries with no corresponding accept
1814 Ent := First_Entity (Spec_Id);
1815 while Present (Ent) loop
1817 and then not Entry_Accepted (Ent)
1818 and then Comes_From_Source (Ent)
1820 Error_Msg_NE ("no accept for entry &?", N, Ent);
1827 Process_End_Label (Handled_Statement_Sequence (N), 't', Ref_Id);
1829 end Analyze_Task_Body;
1831 -----------------------------
1832 -- Analyze_Task_Definition --
1833 -----------------------------
1835 procedure Analyze_Task_Definition (N : Node_Id) is
1839 Tasking_Used := True;
1841 if Present (Visible_Declarations (N)) then
1842 Analyze_Declarations (Visible_Declarations (N));
1845 if Present (Private_Declarations (N)) then
1846 L := Last_Entity (Current_Scope);
1847 Analyze_Declarations (Private_Declarations (N));
1850 Set_First_Private_Entity
1851 (Current_Scope, Next_Entity (L));
1853 Set_First_Private_Entity
1854 (Current_Scope, First_Entity (Current_Scope));
1858 Check_Max_Entries (N, Max_Task_Entries);
1859 Process_End_Label (N, 'e', Current_Scope);
1860 end Analyze_Task_Definition;
1862 -----------------------
1863 -- Analyze_Task_Type --
1864 -----------------------
1866 procedure Analyze_Task_Type (N : Node_Id) is
1868 Def_Id : constant Entity_Id := Defining_Identifier (N);
1870 Iface_Typ : Entity_Id;
1873 Check_Restriction (No_Tasking, N);
1874 Tasking_Used := True;
1875 T := Find_Type_Name (N);
1876 Generate_Definition (T);
1878 if Ekind (T) = E_Incomplete_Type then
1880 Set_Completion_Referenced (T);
1883 Set_Ekind (T, E_Task_Type);
1884 Set_Is_First_Subtype (T, True);
1885 Set_Has_Task (T, True);
1886 Init_Size_Align (T);
1888 Set_Has_Delayed_Freeze (T, True);
1889 Set_Stored_Constraint (T, No_Elist);
1892 -- Ada 2005 (AI-345)
1894 if Present (Interface_List (N)) then
1895 Set_Is_Tagged_Type (T);
1897 Iface := First (Interface_List (N));
1898 while Present (Iface) loop
1899 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
1901 if not Is_Interface (Iface_Typ) then
1902 Error_Msg_NE ("(Ada 2005) & must be an interface",
1906 -- Ada 2005 (AI-251): The declaration of a specific descendant
1907 -- of an interface type freezes the interface type (RM 13.14).
1909 Freeze_Before (N, Etype (Iface));
1911 -- Ada 2005 (AI-345): Task types can only implement limited,
1912 -- synchronized or task interfaces.
1914 if Is_Limited_Interface (Iface_Typ)
1915 or else Is_Synchronized_Interface (Iface_Typ)
1916 or else Is_Task_Interface (Iface_Typ)
1920 elsif Is_Protected_Interface (Iface_Typ) then
1921 Error_Msg_N ("(Ada 2005) task type cannot implement a " &
1922 "protected interface", Iface);
1925 Error_Msg_N ("(Ada 2005) task type cannot implement a " &
1926 "non-limited interface", Iface);
1933 -- If this is the full-declaration associated with a private
1934 -- declaration that implement interfaces, then the private
1935 -- type declaration must be limited.
1937 if Has_Private_Declaration (T) then
1942 E := First_Entity (Scope (T));
1944 pragma Assert (Present (E));
1946 if Is_Type (E) and then Present (Full_View (E)) then
1947 exit when Full_View (E) = T;
1953 if not Is_Limited_Record (E) then
1954 Error_Msg_Sloc := Sloc (E);
1956 ("(Ada 2005) private type declaration # must be limited",
1963 if Present (Discriminant_Specifications (N)) then
1964 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
1965 Error_Msg_N ("(Ada 83) task discriminant not allowed!", N);
1968 if Has_Discriminants (T) then
1970 -- Install discriminants. Also, verify conformance of
1971 -- discriminants of previous and current view. ???
1973 Install_Declarations (T);
1975 Process_Discriminants (N);
1979 Set_Is_Constrained (T, not Has_Discriminants (T));
1981 if Present (Task_Definition (N)) then
1982 Analyze_Task_Definition (Task_Definition (N));
1985 if not Is_Library_Level_Entity (T) then
1986 Check_Restriction (No_Task_Hierarchy, N);
1991 -- Case of a completion of a private declaration
1994 and then Is_Private_Type (Def_Id)
1996 -- Deal with preelaborable initialization. Note that this processing
1997 -- is done by Process_Full_View, but as can be seen below, in this
1998 -- case the call to Process_Full_View is skipped if any serious
1999 -- errors have occurred, and we don't want to lose this check.
2001 if Known_To_Have_Preelab_Init (Def_Id) then
2002 Set_Must_Have_Preelab_Init (T);
2005 -- Create corresponding record now, because some private dependents
2006 -- may be subtypes of the partial view. Skip if errors are present,
2007 -- to prevent cascaded messages.
2009 if Serious_Errors_Detected = 0 then
2010 Exp_Ch9.Expand_N_Task_Type_Declaration (N);
2011 Process_Full_View (N, T, Def_Id);
2014 end Analyze_Task_Type;
2016 -----------------------------------
2017 -- Analyze_Terminate_Alternative --
2018 -----------------------------------
2020 procedure Analyze_Terminate_Alternative (N : Node_Id) is
2022 Tasking_Used := True;
2024 if Present (Pragmas_Before (N)) then
2025 Analyze_List (Pragmas_Before (N));
2028 if Present (Condition (N)) then
2029 Analyze_And_Resolve (Condition (N), Any_Boolean);
2031 end Analyze_Terminate_Alternative;
2033 ------------------------------
2034 -- Analyze_Timed_Entry_Call --
2035 ------------------------------
2037 procedure Analyze_Timed_Entry_Call (N : Node_Id) is
2039 Check_Restriction (No_Select_Statements, N);
2040 Tasking_Used := True;
2041 Analyze (Entry_Call_Alternative (N));
2042 Analyze (Delay_Alternative (N));
2043 end Analyze_Timed_Entry_Call;
2045 ------------------------------------
2046 -- Analyze_Triggering_Alternative --
2047 ------------------------------------
2049 procedure Analyze_Triggering_Alternative (N : Node_Id) is
2050 Trigger : constant Node_Id := Triggering_Statement (N);
2053 Tasking_Used := True;
2055 if Present (Pragmas_Before (N)) then
2056 Analyze_List (Pragmas_Before (N));
2061 if Comes_From_Source (Trigger)
2062 and then Nkind (Trigger) not in N_Delay_Statement
2063 and then Nkind (Trigger) /= N_Entry_Call_Statement
2065 if Ada_Version < Ada_05 then
2067 ("triggering statement must be delay or entry call", Trigger);
2069 -- Ada 2005 (AI-345): If a procedure_call_statement is used for a
2070 -- procedure_or_entry_call, the procedure_name or pro- cedure_prefix
2071 -- of the procedure_call_statement shall denote an entry renamed by a
2072 -- procedure, or (a view of) a primitive subprogram of a limited
2073 -- interface whose first parameter is a controlling parameter.
2075 elsif Nkind (Trigger) = N_Procedure_Call_Statement
2076 and then not Is_Renamed_Entry (Entity (Name (Trigger)))
2077 and then not Is_Controlling_Limited_Procedure
2078 (Entity (Name (Trigger)))
2080 Error_Msg_N ("triggering statement must be delay, procedure " &
2081 "or entry call", Trigger);
2085 if Is_Non_Empty_List (Statements (N)) then
2086 Analyze_Statements (Statements (N));
2088 end Analyze_Triggering_Alternative;
2090 -----------------------
2091 -- Check_Max_Entries --
2092 -----------------------
2094 procedure Check_Max_Entries (D : Node_Id; R : All_Parameter_Restrictions) is
2097 procedure Count (L : List_Id);
2098 -- Count entries in given declaration list
2104 procedure Count (L : List_Id) is
2113 while Present (D) loop
2114 if Nkind (D) = N_Entry_Declaration then
2116 DSD : constant Node_Id :=
2117 Discrete_Subtype_Definition (D);
2120 -- If not an entry family, then just one entry
2123 Ecount := Ecount + 1;
2125 -- If entry family with static bounds, count entries
2127 elsif Is_OK_Static_Subtype (Etype (DSD)) then
2129 Lo : constant Uint :=
2131 (Type_Low_Bound (Etype (DSD)));
2132 Hi : constant Uint :=
2134 (Type_High_Bound (Etype (DSD)));
2138 Ecount := Ecount + Hi - Lo + 1;
2142 -- Entry family with non-static bounds
2145 -- If restriction is set, then this is an error
2147 if Restrictions.Set (R) then
2149 ("static subtype required by Restriction pragma",
2152 -- Otherwise we record an unknown count restriction
2155 Check_Restriction (R, D);
2165 -- Start of processing for Check_Max_Entries
2169 Count (Visible_Declarations (D));
2170 Count (Private_Declarations (D));
2173 Check_Restriction (R, D, Ecount);
2175 end Check_Max_Entries;
2177 --------------------------
2178 -- Find_Concurrent_Spec --
2179 --------------------------
2181 function Find_Concurrent_Spec (Body_Id : Entity_Id) return Entity_Id is
2182 Spec_Id : Entity_Id := Current_Entity_In_Scope (Body_Id);
2185 -- The type may have been given by an incomplete type declaration.
2186 -- Find full view now.
2188 if Present (Spec_Id) and then Ekind (Spec_Id) = E_Incomplete_Type then
2189 Spec_Id := Full_View (Spec_Id);
2193 end Find_Concurrent_Spec;
2195 --------------------------
2196 -- Install_Declarations --
2197 --------------------------
2199 procedure Install_Declarations (Spec : Entity_Id) is
2203 E := First_Entity (Spec);
2204 while Present (E) loop
2205 Prev := Current_Entity (E);
2206 Set_Current_Entity (E);
2207 Set_Is_Immediately_Visible (E);
2208 Set_Homonym (E, Prev);
2211 end Install_Declarations;