1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2011, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree; use Atree;
27 with Checks; use Checks;
28 with Einfo; use Einfo;
29 with Errout; use Errout;
30 with Exp_Ch9; use Exp_Ch9;
31 with Elists; use Elists;
32 with Freeze; use Freeze;
33 with Lib.Xref; use Lib.Xref;
34 with Namet; use Namet;
35 with Nlists; use Nlists;
36 with Nmake; use Nmake;
38 with Restrict; use Restrict;
39 with Rident; use Rident;
40 with Rtsfind; use Rtsfind;
42 with Sem_Aux; use Sem_Aux;
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_Ch13; use Sem_Ch13;
48 with Sem_Eval; use Sem_Eval;
49 with Sem_Res; use Sem_Res;
50 with Sem_Type; use Sem_Type;
51 with Sem_Util; use Sem_Util;
52 with Sem_Warn; use Sem_Warn;
53 with Snames; use Snames;
54 with Stand; use Stand;
55 with Sinfo; use Sinfo;
57 with Targparm; use Targparm;
58 with Tbuild; use Tbuild;
59 with Uintp; use Uintp;
61 package body Sem_Ch9 is
63 -----------------------
64 -- Local Subprograms --
65 -----------------------
67 procedure Check_Max_Entries (D : Node_Id; R : All_Parameter_Restrictions);
68 -- Given either a protected definition or a task definition in D, check
69 -- the corresponding restriction parameter identifier R, and if it is set,
70 -- count the entries (checking the static requirement), and compare with
73 procedure Check_Interfaces (N : Node_Id; T : Entity_Id);
74 -- N is an N_Protected_Type_Declaration or N_Task_Type_Declaration node.
75 -- Complete decoration of T and check legality of the covered interfaces.
77 procedure Check_Triggering_Statement
80 Is_Dispatching : out Boolean);
81 -- Examine the triggering statement of a select statement, conditional or
82 -- timed entry call. If Trigger is a dispatching call, return its status
83 -- in Is_Dispatching and check whether the primitive belongs to a limited
84 -- interface. If it does not, emit an error at Error_Node.
86 function Find_Concurrent_Spec (Body_Id : Entity_Id) return Entity_Id;
87 -- Find entity in corresponding task or protected declaration. Use full
88 -- view if first declaration was for an incomplete type.
90 procedure Install_Declarations (Spec : Entity_Id);
91 -- Utility to make visible in corresponding body the entities defined in
92 -- task, protected type declaration, or entry declaration.
94 -----------------------------
95 -- Analyze_Abort_Statement --
96 -----------------------------
98 procedure Analyze_Abort_Statement (N : Node_Id) is
102 Tasking_Used := True;
103 Check_SPARK_Restriction ("abort statement is not allowed", N);
105 T_Name := First (Names (N));
106 while Present (T_Name) loop
109 if Is_Task_Type (Etype (T_Name))
110 or else (Ada_Version >= Ada_2005
111 and then Ekind (Etype (T_Name)) = E_Class_Wide_Type
112 and then Is_Interface (Etype (T_Name))
113 and then Is_Task_Interface (Etype (T_Name)))
117 if Ada_Version >= Ada_2005 then
118 Error_Msg_N ("expect task name or task interface class-wide "
119 & "object for ABORT", T_Name);
121 Error_Msg_N ("expect task name for ABORT", T_Name);
130 Check_Restriction (No_Abort_Statements, N);
131 Check_Potentially_Blocking_Operation (N);
132 end Analyze_Abort_Statement;
134 --------------------------------
135 -- Analyze_Accept_Alternative --
136 --------------------------------
138 procedure Analyze_Accept_Alternative (N : Node_Id) is
140 Tasking_Used := True;
142 if Present (Pragmas_Before (N)) then
143 Analyze_List (Pragmas_Before (N));
146 if Present (Condition (N)) then
147 Analyze_And_Resolve (Condition (N), Any_Boolean);
150 Analyze (Accept_Statement (N));
152 if Is_Non_Empty_List (Statements (N)) then
153 Analyze_Statements (Statements (N));
155 end Analyze_Accept_Alternative;
157 ------------------------------
158 -- Analyze_Accept_Statement --
159 ------------------------------
161 procedure Analyze_Accept_Statement (N : Node_Id) is
162 Nam : constant Entity_Id := Entry_Direct_Name (N);
163 Formals : constant List_Id := Parameter_Specifications (N);
164 Index : constant Node_Id := Entry_Index (N);
165 Stats : constant Node_Id := Handled_Statement_Sequence (N);
166 Accept_Id : Entity_Id;
167 Entry_Nam : Entity_Id;
170 Task_Nam : Entity_Id;
173 Tasking_Used := True;
174 Check_SPARK_Restriction ("accept statement is not allowed", N);
176 -- Entry name is initialized to Any_Id. It should get reset to the
177 -- matching entry entity. An error is signalled if it is not reset.
181 for J in reverse 0 .. Scope_Stack.Last loop
182 Task_Nam := Scope_Stack.Table (J).Entity;
183 exit when Ekind (Etype (Task_Nam)) = E_Task_Type;
184 Kind := Ekind (Task_Nam);
186 if Kind /= E_Block and then Kind /= E_Loop
187 and then not Is_Entry (Task_Nam)
189 Error_Msg_N ("enclosing body of accept must be a task", N);
194 if Ekind (Etype (Task_Nam)) /= E_Task_Type then
195 Error_Msg_N ("invalid context for accept statement", N);
199 -- In order to process the parameters, we create a defining identifier
200 -- that can be used as the name of the scope. The name of the accept
201 -- statement itself is not a defining identifier, and we cannot use
202 -- its name directly because the task may have any number of accept
203 -- statements for the same entry.
205 if Present (Index) then
206 Accept_Id := New_Internal_Entity
207 (E_Entry_Family, Current_Scope, Sloc (N), 'E');
209 Accept_Id := New_Internal_Entity
210 (E_Entry, Current_Scope, Sloc (N), 'E');
213 Set_Etype (Accept_Id, Standard_Void_Type);
214 Set_Accept_Address (Accept_Id, New_Elmt_List);
216 if Present (Formals) then
217 Push_Scope (Accept_Id);
218 Process_Formals (Formals, N);
219 Create_Extra_Formals (Accept_Id);
223 -- We set the default expressions processed flag because we don't need
224 -- default expression functions. This is really more like body entity
225 -- than a spec entity anyway.
227 Set_Default_Expressions_Processed (Accept_Id);
229 E := First_Entity (Etype (Task_Nam));
230 while Present (E) loop
231 if Chars (E) = Chars (Nam)
232 and then (Ekind (E) = Ekind (Accept_Id))
233 and then Type_Conformant (Accept_Id, E)
242 if Entry_Nam = Any_Id then
243 Error_Msg_N ("no entry declaration matches accept statement", N);
246 Set_Entity (Nam, Entry_Nam);
247 Generate_Reference (Entry_Nam, Nam, 'b', Set_Ref => False);
248 Style.Check_Identifier (Nam, Entry_Nam);
251 -- Verify that the entry is not hidden by a procedure declared in the
252 -- current block (pathological but possible).
254 if Current_Scope /= Task_Nam then
259 E1 := First_Entity (Current_Scope);
260 while Present (E1) loop
261 if Ekind (E1) = E_Procedure
262 and then Chars (E1) = Chars (Entry_Nam)
263 and then Type_Conformant (E1, Entry_Nam)
265 Error_Msg_N ("entry name is not visible", N);
273 Set_Convention (Accept_Id, Convention (Entry_Nam));
274 Check_Fully_Conformant (Accept_Id, Entry_Nam, N);
276 for J in reverse 0 .. Scope_Stack.Last loop
277 exit when Task_Nam = Scope_Stack.Table (J).Entity;
279 if Entry_Nam = Scope_Stack.Table (J).Entity then
280 Error_Msg_N ("duplicate accept statement for same entry", N);
290 when N_Task_Body | N_Compilation_Unit =>
292 when N_Asynchronous_Select =>
293 Error_Msg_N ("accept statements are not allowed within" &
294 " an asynchronous select inner" &
295 " to the enclosing task body", N);
303 if Ekind (E) = E_Entry_Family then
305 Error_Msg_N ("missing entry index in accept for entry family", N);
307 Analyze_And_Resolve (Index, Entry_Index_Type (E));
308 Apply_Range_Check (Index, Entry_Index_Type (E));
311 elsif Present (Index) then
312 Error_Msg_N ("invalid entry index in accept for simple entry", N);
315 -- If label declarations present, analyze them. They are declared in the
316 -- enclosing task, but their enclosing scope is the entry itself, so
317 -- that goto's to the label are recognized as local to the accept.
319 if Present (Declarations (N)) then
325 Decl := First (Declarations (N));
326 while Present (Decl) loop
330 (Nkind (Decl) = N_Implicit_Label_Declaration);
332 Id := Defining_Identifier (Decl);
333 Set_Enclosing_Scope (Id, Entry_Nam);
339 -- If statements are present, they must be analyzed in the context of
340 -- the entry, so that references to formals are correctly resolved. We
341 -- also have to add the declarations that are required by the expansion
342 -- of the accept statement in this case if expansion active.
344 -- In the case of a select alternative of a selective accept, the
345 -- expander references the address declaration even if there is no
348 -- We also need to create the renaming declarations for the local
349 -- variables that will replace references to the formals within the
352 Exp_Ch9.Expand_Accept_Declarations (N, Entry_Nam);
354 -- Set Never_Set_In_Source and clear Is_True_Constant/Current_Value
355 -- fields on all entry formals (this loop ignores all other entities).
356 -- Reset Referenced, Referenced_As_xxx and Has_Pragma_Unreferenced as
357 -- well, so that we can post accurate warnings on each accept statement
358 -- for the same entry.
360 E := First_Entity (Entry_Nam);
361 while Present (E) loop
362 if Is_Formal (E) then
363 Set_Never_Set_In_Source (E, True);
364 Set_Is_True_Constant (E, False);
365 Set_Current_Value (E, Empty);
366 Set_Referenced (E, False);
367 Set_Referenced_As_LHS (E, False);
368 Set_Referenced_As_Out_Parameter (E, False);
369 Set_Has_Pragma_Unreferenced (E, False);
375 -- Analyze statements if present
377 if Present (Stats) then
378 Push_Scope (Entry_Nam);
379 Install_Declarations (Entry_Nam);
381 Set_Actual_Subtypes (N, Current_Scope);
384 Process_End_Label (Handled_Statement_Sequence (N), 't', Entry_Nam);
388 -- Some warning checks
390 Check_Potentially_Blocking_Operation (N);
391 Check_References (Entry_Nam, N);
392 Set_Entry_Accepted (Entry_Nam);
393 end Analyze_Accept_Statement;
395 ---------------------------------
396 -- Analyze_Asynchronous_Select --
397 ---------------------------------
399 procedure Analyze_Asynchronous_Select (N : Node_Id) is
400 Is_Disp_Select : Boolean := False;
404 Tasking_Used := True;
405 Check_SPARK_Restriction ("select statement is not allowed", N);
406 Check_Restriction (Max_Asynchronous_Select_Nesting, N);
407 Check_Restriction (No_Select_Statements, N);
409 if Ada_Version >= Ada_2005 then
410 Trigger := Triggering_Statement (Triggering_Alternative (N));
414 -- Ada 2005 (AI-345): Check for a potential dispatching select
416 Check_Triggering_Statement (Trigger, N, Is_Disp_Select);
419 -- Ada 2005 (AI-345): The expansion of the dispatching asynchronous
420 -- select will have to duplicate the triggering statements. Postpone
421 -- the analysis of the statements till expansion. Analyze only if the
422 -- expander is disabled in order to catch any semantic errors.
424 if Is_Disp_Select then
425 if not Expander_Active then
426 Analyze_Statements (Statements (Abortable_Part (N)));
427 Analyze (Triggering_Alternative (N));
430 -- Analyze the statements. We analyze statements in the abortable part,
431 -- because this is the section that is executed first, and that way our
432 -- remembering of saved values and checks is accurate.
435 Analyze_Statements (Statements (Abortable_Part (N)));
436 Analyze (Triggering_Alternative (N));
438 end Analyze_Asynchronous_Select;
440 ------------------------------------
441 -- Analyze_Conditional_Entry_Call --
442 ------------------------------------
444 procedure Analyze_Conditional_Entry_Call (N : Node_Id) is
445 Trigger : constant Node_Id :=
446 Entry_Call_Statement (Entry_Call_Alternative (N));
447 Is_Disp_Select : Boolean := False;
450 Tasking_Used := True;
451 Check_SPARK_Restriction ("select statement is not allowed", N);
452 Check_Restriction (No_Select_Statements, N);
454 -- Ada 2005 (AI-345): The trigger may be a dispatching call
456 if Ada_Version >= Ada_2005 then
458 Check_Triggering_Statement (Trigger, N, Is_Disp_Select);
461 if List_Length (Else_Statements (N)) = 1
462 and then Nkind (First (Else_Statements (N))) in N_Delay_Statement
465 ("suspicious form of conditional entry call?!", N);
467 ("\`SELECT OR` may be intended rather than `SELECT ELSE`!", N);
470 -- Postpone the analysis of the statements till expansion. Analyze only
471 -- if the expander is disabled in order to catch any semantic errors.
473 if Is_Disp_Select then
474 if not Expander_Active then
475 Analyze (Entry_Call_Alternative (N));
476 Analyze_Statements (Else_Statements (N));
479 -- Regular select analysis
482 Analyze (Entry_Call_Alternative (N));
483 Analyze_Statements (Else_Statements (N));
485 end Analyze_Conditional_Entry_Call;
487 --------------------------------
488 -- Analyze_Delay_Alternative --
489 --------------------------------
491 procedure Analyze_Delay_Alternative (N : Node_Id) is
496 Tasking_Used := True;
497 Check_Restriction (No_Delay, N);
499 if Present (Pragmas_Before (N)) then
500 Analyze_List (Pragmas_Before (N));
503 if Nkind_In (Parent (N), N_Selective_Accept, N_Timed_Entry_Call) then
504 Expr := Expression (Delay_Statement (N));
506 -- Defer full analysis until the statement is expanded, to insure
507 -- that generated code does not move past the guard. The delay
508 -- expression is only evaluated if the guard is open.
510 if Nkind (Delay_Statement (N)) = N_Delay_Relative_Statement then
511 Preanalyze_And_Resolve (Expr, Standard_Duration);
513 Preanalyze_And_Resolve (Expr);
516 Typ := First_Subtype (Etype (Expr));
518 if Nkind (Delay_Statement (N)) = N_Delay_Until_Statement
519 and then not Is_RTE (Typ, RO_CA_Time)
520 and then not Is_RTE (Typ, RO_RT_Time)
522 Error_Msg_N ("expect Time types for `DELAY UNTIL`", Expr);
525 Check_Restriction (No_Fixed_Point, Expr);
528 Analyze (Delay_Statement (N));
531 if Present (Condition (N)) then
532 Analyze_And_Resolve (Condition (N), Any_Boolean);
535 if Is_Non_Empty_List (Statements (N)) then
536 Analyze_Statements (Statements (N));
538 end Analyze_Delay_Alternative;
540 ----------------------------
541 -- Analyze_Delay_Relative --
542 ----------------------------
544 procedure Analyze_Delay_Relative (N : Node_Id) is
545 E : constant Node_Id := Expression (N);
547 Tasking_Used := True;
548 Check_SPARK_Restriction ("delay statement is not allowed", N);
549 Check_Restriction (No_Relative_Delay, N);
550 Check_Restriction (No_Delay, N);
551 Check_Potentially_Blocking_Operation (N);
552 Analyze_And_Resolve (E, Standard_Duration);
553 Check_Restriction (No_Fixed_Point, E);
554 end Analyze_Delay_Relative;
556 -------------------------
557 -- Analyze_Delay_Until --
558 -------------------------
560 procedure Analyze_Delay_Until (N : Node_Id) is
561 E : constant Node_Id := Expression (N);
565 Tasking_Used := True;
566 Check_SPARK_Restriction ("delay statement is not allowed", N);
567 Check_Restriction (No_Delay, N);
568 Check_Potentially_Blocking_Operation (N);
570 Typ := First_Subtype (Etype (E));
572 if not Is_RTE (Typ, RO_CA_Time) and then
573 not Is_RTE (Typ, RO_RT_Time)
575 Error_Msg_N ("expect Time types for `DELAY UNTIL`", E);
577 end Analyze_Delay_Until;
579 ------------------------
580 -- Analyze_Entry_Body --
581 ------------------------
583 procedure Analyze_Entry_Body (N : Node_Id) is
584 Id : constant Entity_Id := Defining_Identifier (N);
585 Decls : constant List_Id := Declarations (N);
586 Stats : constant Node_Id := Handled_Statement_Sequence (N);
587 Formals : constant Node_Id := Entry_Body_Formal_Part (N);
588 P_Type : constant Entity_Id := Current_Scope;
590 Entry_Name : Entity_Id;
593 Tasking_Used := True;
595 -- Entry_Name is initialized to Any_Id. It should get reset to the
596 -- matching entry entity. An error is signalled if it is not reset
598 Entry_Name := Any_Id;
602 if Present (Entry_Index_Specification (Formals)) then
603 Set_Ekind (Id, E_Entry_Family);
605 Set_Ekind (Id, E_Entry);
608 Set_Scope (Id, Current_Scope);
609 Set_Etype (Id, Standard_Void_Type);
610 Set_Accept_Address (Id, New_Elmt_List);
612 E := First_Entity (P_Type);
613 while Present (E) loop
614 if Chars (E) = Chars (Id)
615 and then (Ekind (E) = Ekind (Id))
616 and then Type_Conformant (Id, E)
619 Set_Convention (Id, Convention (E));
620 Set_Corresponding_Body (Parent (Entry_Name), Id);
621 Check_Fully_Conformant (Id, E, N);
623 if Ekind (Id) = E_Entry_Family then
624 if not Fully_Conformant_Discrete_Subtypes (
625 Discrete_Subtype_Definition (Parent (E)),
626 Discrete_Subtype_Definition
627 (Entry_Index_Specification (Formals)))
630 ("index not fully conformant with previous declaration",
631 Discrete_Subtype_Definition
632 (Entry_Index_Specification (Formals)));
635 -- The elaboration of the entry body does not recompute the
636 -- bounds of the index, which may have side effects. Inherit
637 -- the bounds from the entry declaration. This is critical
638 -- if the entry has a per-object constraint. If a bound is
639 -- given by a discriminant, it must be reanalyzed in order
640 -- to capture the discriminal of the current entry, rather
641 -- than that of the protected type.
644 Index_Spec : constant Node_Id :=
645 Entry_Index_Specification (Formals);
647 Def : constant Node_Id :=
649 (Discrete_Subtype_Definition (Parent (E)));
654 (Discrete_Subtype_Definition (Index_Spec))) = N_Range
656 Set_Etype (Def, Empty);
657 Set_Analyzed (Def, False);
659 -- Keep the original subtree to ensure a properly
660 -- formed tree (e.g. for ASIS use).
663 (Discrete_Subtype_Definition (Index_Spec), Def);
665 Set_Analyzed (Low_Bound (Def), False);
666 Set_Analyzed (High_Bound (Def), False);
668 if Denotes_Discriminant (Low_Bound (Def)) then
669 Set_Entity (Low_Bound (Def), Empty);
672 if Denotes_Discriminant (High_Bound (Def)) then
673 Set_Entity (High_Bound (Def), Empty);
677 Make_Index (Def, Index_Spec);
679 (Defining_Identifier (Index_Spec), Etype (Def));
691 if Entry_Name = Any_Id then
692 Error_Msg_N ("no entry declaration matches entry body", N);
695 elsif Has_Completion (Entry_Name) then
696 Error_Msg_N ("duplicate entry body", N);
700 Set_Has_Completion (Entry_Name);
701 Generate_Reference (Entry_Name, Id, 'b', Set_Ref => False);
702 Style.Check_Identifier (Id, Entry_Name);
705 Exp_Ch9.Expand_Entry_Barrier (N, Entry_Name);
706 Push_Scope (Entry_Name);
708 Install_Declarations (Entry_Name);
709 Set_Actual_Subtypes (N, Current_Scope);
711 -- The entity for the protected subprogram corresponding to the entry
712 -- has been created. We retain the name of this entity in the entry
713 -- body, for use when the corresponding subprogram body is created.
714 -- Note that entry bodies have no corresponding_spec, and there is no
715 -- easy link back in the tree between the entry body and the entity for
716 -- the entry itself, which is why we must propagate some attributes
717 -- explicitly from spec to body.
719 Set_Protected_Body_Subprogram
720 (Id, Protected_Body_Subprogram (Entry_Name));
722 Set_Entry_Parameters_Type
723 (Id, Entry_Parameters_Type (Entry_Name));
725 -- Add a declaration for the Protection object, renaming declarations
726 -- for the discriminals and privals and finally a declaration for the
727 -- entry family index (if applicable).
729 if Full_Expander_Active
730 and then Is_Protected_Type (P_Type)
732 Install_Private_Data_Declarations
733 (Sloc (N), Entry_Name, P_Type, N, Decls);
736 if Present (Decls) then
737 Analyze_Declarations (Decls);
738 Inspect_Deferred_Constant_Completion (Decls);
741 if Present (Stats) then
745 -- Check for unreferenced variables etc. Before the Check_References
746 -- call, we transfer Never_Set_In_Source and Referenced flags from
747 -- parameters in the spec to the corresponding entities in the body,
748 -- since we want the warnings on the body entities. Note that we do
749 -- not have to transfer Referenced_As_LHS, since that flag can only
750 -- be set for simple variables.
752 -- At the same time, we set the flags on the spec entities to suppress
753 -- any warnings on the spec formals, since we also scan the spec.
754 -- Finally, we propagate the Entry_Component attribute to the body
755 -- formals, for use in the renaming declarations created later for the
756 -- formals (see exp_ch9.Add_Formal_Renamings).
763 E1 := First_Entity (Entry_Name);
764 while Present (E1) loop
765 E2 := First_Entity (Id);
766 while Present (E2) loop
767 exit when Chars (E1) = Chars (E2);
771 -- If no matching body entity, then we already had a detected
772 -- error of some kind, so just don't worry about these warnings.
778 if Ekind (E1) = E_Out_Parameter then
779 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
780 Set_Never_Set_In_Source (E1, False);
783 Set_Referenced (E2, Referenced (E1));
785 Set_Entry_Component (E2, Entry_Component (E1));
791 Check_References (Id);
794 -- We still need to check references for the spec, since objects
795 -- declared in the body are chained (in the First_Entity sense) to
796 -- the spec rather than the body in the case of entries.
798 Check_References (Entry_Name);
800 -- Process the end label, and terminate the scope
802 Process_End_Label (Handled_Statement_Sequence (N), 't', Entry_Name);
805 -- If this is an entry family, remove the loop created to provide
806 -- a scope for the entry index.
808 if Ekind (Id) = E_Entry_Family
809 and then Present (Entry_Index_Specification (Formals))
813 end Analyze_Entry_Body;
815 ------------------------------------
816 -- Analyze_Entry_Body_Formal_Part --
817 ------------------------------------
819 procedure Analyze_Entry_Body_Formal_Part (N : Node_Id) is
820 Id : constant Entity_Id := Defining_Identifier (Parent (N));
821 Index : constant Node_Id := Entry_Index_Specification (N);
822 Formals : constant List_Id := Parameter_Specifications (N);
825 Tasking_Used := True;
827 if Present (Index) then
830 -- The entry index functions like a loop variable, thus it is known
831 -- to have a valid value.
833 Set_Is_Known_Valid (Defining_Identifier (Index));
836 if Present (Formals) then
837 Set_Scope (Id, Current_Scope);
839 Process_Formals (Formals, Parent (N));
842 end Analyze_Entry_Body_Formal_Part;
844 ------------------------------------
845 -- Analyze_Entry_Call_Alternative --
846 ------------------------------------
848 procedure Analyze_Entry_Call_Alternative (N : Node_Id) is
849 Call : constant Node_Id := Entry_Call_Statement (N);
852 Tasking_Used := True;
853 Check_SPARK_Restriction ("entry call is not allowed", N);
855 if Present (Pragmas_Before (N)) then
856 Analyze_List (Pragmas_Before (N));
859 if Nkind (Call) = N_Attribute_Reference then
861 -- Possibly a stream attribute, but definitely illegal. Other
862 -- illegalities, such as procedure calls, are diagnosed after
865 Error_Msg_N ("entry call alternative requires an entry call", Call);
871 if Is_Non_Empty_List (Statements (N)) then
872 Analyze_Statements (Statements (N));
874 end Analyze_Entry_Call_Alternative;
876 -------------------------------
877 -- Analyze_Entry_Declaration --
878 -------------------------------
880 procedure Analyze_Entry_Declaration (N : Node_Id) is
881 D_Sdef : constant Node_Id := Discrete_Subtype_Definition (N);
882 Def_Id : constant Entity_Id := Defining_Identifier (N);
883 Formals : constant List_Id := Parameter_Specifications (N);
886 Generate_Definition (Def_Id);
887 Set_Contract (Def_Id, Make_Contract (Sloc (Def_Id)));
888 Tasking_Used := True;
890 -- Case of no discrete subtype definition
893 Set_Ekind (Def_Id, E_Entry);
895 -- Processing for discrete subtype definition present
899 Set_Ekind (Def_Id, E_Entry_Family);
901 Make_Index (D_Sdef, N, Def_Id);
903 -- Check subtype with predicate in entry family
905 Bad_Predicated_Subtype_Use
906 ("subtype& has predicate, not allowed in entry family",
907 D_Sdef, Etype (D_Sdef));
912 Set_Etype (Def_Id, Standard_Void_Type);
913 Set_Convention (Def_Id, Convention_Entry);
914 Set_Accept_Address (Def_Id, New_Elmt_List);
918 if Present (Formals) then
919 Set_Scope (Def_Id, Current_Scope);
921 Process_Formals (Formals, N);
922 Create_Extra_Formals (Def_Id);
926 if Ekind (Def_Id) = E_Entry then
927 New_Overloaded_Entity (Def_Id);
930 Generate_Reference_To_Formals (Def_Id);
932 if Has_Aspects (N) then
933 Analyze_Aspect_Specifications (N, Def_Id);
935 end Analyze_Entry_Declaration;
937 ---------------------------------------
938 -- Analyze_Entry_Index_Specification --
939 ---------------------------------------
941 -- The Defining_Identifier of the entry index specification is local to the
942 -- entry body, but it must be available in the entry barrier which is
943 -- evaluated outside of the entry body. The index is eventually renamed as
944 -- a run-time object, so is visibility is strictly a front-end concern. In
945 -- order to make it available to the barrier, we create an additional
946 -- scope, as for a loop, whose only declaration is the index name. This
947 -- loop is not attached to the tree and does not appear as an entity local
948 -- to the protected type, so its existence need only be known to routines
949 -- that process entry families.
951 procedure Analyze_Entry_Index_Specification (N : Node_Id) is
952 Iden : constant Node_Id := Defining_Identifier (N);
953 Def : constant Node_Id := Discrete_Subtype_Definition (N);
954 Loop_Id : constant Entity_Id := Make_Temporary (Sloc (N), 'L');
957 Tasking_Used := True;
960 -- There is no elaboration of the entry index specification. Therefore,
961 -- if the index is a range, it is not resolved and expanded, but the
962 -- bounds are inherited from the entry declaration, and reanalyzed.
963 -- See Analyze_Entry_Body.
965 if Nkind (Def) /= N_Range then
969 Set_Ekind (Loop_Id, E_Loop);
970 Set_Scope (Loop_Id, Current_Scope);
971 Push_Scope (Loop_Id);
973 Set_Ekind (Iden, E_Entry_Index_Parameter);
974 Set_Etype (Iden, Etype (Def));
975 end Analyze_Entry_Index_Specification;
977 ----------------------------
978 -- Analyze_Protected_Body --
979 ----------------------------
981 procedure Analyze_Protected_Body (N : Node_Id) is
982 Body_Id : constant Entity_Id := Defining_Identifier (N);
986 -- This is initially the entity of the protected object or protected
987 -- type involved, but is replaced by the protected type always in the
988 -- case of a single protected declaration, since this is the proper
992 -- This is the entity of the protected object or protected type
993 -- involved, and is the entity used for cross-reference purposes (it
994 -- differs from Spec_Id in the case of a single protected object, since
995 -- Spec_Id is set to the protected type in this case).
998 Tasking_Used := True;
999 Set_Ekind (Body_Id, E_Protected_Body);
1000 Spec_Id := Find_Concurrent_Spec (Body_Id);
1002 if Present (Spec_Id)
1003 and then Ekind (Spec_Id) = E_Protected_Type
1007 elsif Present (Spec_Id)
1008 and then Ekind (Etype (Spec_Id)) = E_Protected_Type
1009 and then not Comes_From_Source (Etype (Spec_Id))
1014 Error_Msg_N ("missing specification for protected body", Body_Id);
1019 Generate_Reference (Ref_Id, Body_Id, 'b', Set_Ref => False);
1020 Style.Check_Identifier (Body_Id, Spec_Id);
1022 -- The declarations are always attached to the type
1024 if Ekind (Spec_Id) /= E_Protected_Type then
1025 Spec_Id := Etype (Spec_Id);
1028 Push_Scope (Spec_Id);
1029 Set_Corresponding_Spec (N, Spec_Id);
1030 Set_Corresponding_Body (Parent (Spec_Id), Body_Id);
1031 Set_Has_Completion (Spec_Id);
1032 Install_Declarations (Spec_Id);
1034 Expand_Protected_Body_Declarations (N, Spec_Id);
1036 Last_E := Last_Entity (Spec_Id);
1038 Analyze_Declarations (Declarations (N));
1040 -- For visibility purposes, all entities in the body are private. Set
1041 -- First_Private_Entity accordingly, if there was no private part in the
1042 -- protected declaration.
1044 if No (First_Private_Entity (Spec_Id)) then
1045 if Present (Last_E) then
1046 Set_First_Private_Entity (Spec_Id, Next_Entity (Last_E));
1048 Set_First_Private_Entity (Spec_Id, First_Entity (Spec_Id));
1052 Check_Completion (Body_Id);
1053 Check_References (Spec_Id);
1054 Process_End_Label (N, 't', Ref_Id);
1056 end Analyze_Protected_Body;
1058 ----------------------------------
1059 -- Analyze_Protected_Definition --
1060 ----------------------------------
1062 procedure Analyze_Protected_Definition (N : Node_Id) is
1066 procedure Undelay_Itypes (T : Entity_Id);
1067 -- Itypes created for the private components of a protected type
1068 -- do not receive freeze nodes, because there is no scope in which
1069 -- they can be elaborated, and they can depend on discriminants of
1070 -- the enclosed protected type. Given that the components can be
1071 -- composite types with inner components, we traverse recursively
1072 -- the private components of the protected type, and indicate that
1073 -- all itypes within are frozen. This ensures that no freeze nodes
1074 -- will be generated for them.
1076 -- On the other hand, components of the corresponding record are
1077 -- frozen (or receive itype references) as for other records.
1079 --------------------
1080 -- Undelay_Itypes --
1081 --------------------
1083 procedure Undelay_Itypes (T : Entity_Id) is
1087 if Is_Protected_Type (T) then
1088 Comp := First_Private_Entity (T);
1089 elsif Is_Record_Type (T) then
1090 Comp := First_Entity (T);
1095 while Present (Comp) loop
1097 and then Is_Itype (Comp)
1099 Set_Has_Delayed_Freeze (Comp, False);
1100 Set_Is_Frozen (Comp);
1102 if Is_Record_Type (Comp)
1103 or else Is_Protected_Type (Comp)
1105 Undelay_Itypes (Comp);
1113 -- Start of processing for Analyze_Protected_Definition
1116 Tasking_Used := True;
1117 Check_SPARK_Restriction ("protected definition is not allowed", N);
1118 Analyze_Declarations (Visible_Declarations (N));
1120 if Present (Private_Declarations (N))
1121 and then not Is_Empty_List (Private_Declarations (N))
1123 L := Last_Entity (Current_Scope);
1124 Analyze_Declarations (Private_Declarations (N));
1127 Set_First_Private_Entity (Current_Scope, Next_Entity (L));
1129 Set_First_Private_Entity (Current_Scope,
1130 First_Entity (Current_Scope));
1134 E := First_Entity (Current_Scope);
1135 while Present (E) loop
1136 if Ekind_In (E, E_Function, E_Procedure) then
1137 Set_Convention (E, Convention_Protected);
1139 elsif Is_Task_Type (Etype (E))
1140 or else Has_Task (Etype (E))
1142 Set_Has_Task (Current_Scope);
1148 Undelay_Itypes (Current_Scope);
1150 Check_Max_Entries (N, Max_Protected_Entries);
1151 Process_End_Label (N, 'e', Current_Scope);
1152 end Analyze_Protected_Definition;
1154 ----------------------------------------
1155 -- Analyze_Protected_Type_Declaration --
1156 ----------------------------------------
1158 procedure Analyze_Protected_Type_Declaration (N : Node_Id) is
1159 Def_Id : constant Entity_Id := Defining_Identifier (N);
1164 if No_Run_Time_Mode then
1165 Error_Msg_CRT ("protected type", N);
1169 Tasking_Used := True;
1170 Check_Restriction (No_Protected_Types, N);
1172 T := Find_Type_Name (N);
1174 -- In the case of an incomplete type, use the full view, unless it's not
1175 -- present (as can occur for an incomplete view from a limited with).
1177 if Ekind (T) = E_Incomplete_Type and then Present (Full_View (T)) then
1179 Set_Completion_Referenced (T);
1182 Set_Ekind (T, E_Protected_Type);
1183 Set_Is_First_Subtype (T, True);
1184 Init_Size_Align (T);
1186 Set_Has_Delayed_Freeze (T, True);
1187 Set_Stored_Constraint (T, No_Elist);
1190 if Ada_Version >= Ada_2005 then
1191 Check_Interfaces (N, T);
1194 if Present (Discriminant_Specifications (N)) then
1195 if Has_Discriminants (T) then
1197 -- Install discriminants. Also, verify conformance of
1198 -- discriminants of previous and current view. ???
1200 Install_Declarations (T);
1202 Process_Discriminants (N);
1206 Set_Is_Constrained (T, not Has_Discriminants (T));
1208 Analyze (Protected_Definition (N));
1210 -- In the case where the protected type is declared at a nested level
1211 -- and the No_Local_Protected_Objects restriction applies, issue a
1212 -- warning that objects of the type will violate the restriction.
1214 if Restriction_Check_Required (No_Local_Protected_Objects)
1215 and then not Is_Library_Level_Entity (T)
1216 and then Comes_From_Source (T)
1218 Error_Msg_Sloc := Restrictions_Loc (No_Local_Protected_Objects);
1220 if Error_Msg_Sloc = No_Location then
1222 ("objects of this type will violate " &
1223 "`No_Local_Protected_Objects`?", N);
1226 ("objects of this type will violate " &
1227 "`No_Local_Protected_Objects`?#", N);
1231 -- Protected types with entries are controlled (because of the
1232 -- Protection component if nothing else), same for any protected type
1233 -- with interrupt handlers. Note that we need to analyze the protected
1234 -- definition to set Has_Entries and such.
1236 if (Abort_Allowed or else Restriction_Active (No_Entry_Queue) = False
1237 or else Number_Entries (T) > 1)
1240 or else Has_Interrupt_Handler (T)
1241 or else Has_Attach_Handler (T))
1243 Set_Has_Controlled_Component (T, True);
1246 -- The Ekind of components is E_Void during analysis to detect illegal
1247 -- uses. Now it can be set correctly.
1249 E := First_Entity (Current_Scope);
1250 while Present (E) loop
1251 if Ekind (E) = E_Void then
1252 Set_Ekind (E, E_Component);
1253 Init_Component_Location (E);
1261 -- Case of a completion of a private declaration
1264 and then Is_Private_Type (Def_Id)
1266 -- Deal with preelaborable initialization. Note that this processing
1267 -- is done by Process_Full_View, but as can be seen below, in this
1268 -- case the call to Process_Full_View is skipped if any serious
1269 -- errors have occurred, and we don't want to lose this check.
1271 if Known_To_Have_Preelab_Init (Def_Id) then
1272 Set_Must_Have_Preelab_Init (T);
1275 -- Create corresponding record now, because some private dependents
1276 -- may be subtypes of the partial view.
1278 -- Skip if errors are present, to prevent cascaded messages
1280 if Serious_Errors_Detected = 0
1282 -- Also skip if expander is not active
1284 and then Full_Expander_Active
1286 Expand_N_Protected_Type_Declaration (N);
1287 Process_Full_View (N, T, Def_Id);
1292 if Has_Aspects (N) then
1293 Analyze_Aspect_Specifications (N, Def_Id);
1295 end Analyze_Protected_Type_Declaration;
1297 ---------------------
1298 -- Analyze_Requeue --
1299 ---------------------
1301 procedure Analyze_Requeue (N : Node_Id) is
1302 Count : Natural := 0;
1303 Entry_Name : Node_Id := Name (N);
1304 Entry_Id : Entity_Id;
1306 Is_Disp_Req : Boolean;
1308 Enclosing : Entity_Id;
1309 Target_Obj : Node_Id := Empty;
1310 Req_Scope : Entity_Id;
1311 Outer_Ent : Entity_Id;
1314 Tasking_Used := True;
1315 Check_SPARK_Restriction ("requeue statement is not allowed", N);
1316 Check_Restriction (No_Requeue_Statements, N);
1317 Check_Unreachable_Code (N);
1320 for J in reverse 0 .. Scope_Stack.Last loop
1321 Enclosing := Scope_Stack.Table (J).Entity;
1322 exit when Is_Entry (Enclosing);
1324 if not Ekind_In (Enclosing, E_Block, E_Loop) then
1325 Error_Msg_N ("requeue must appear within accept or entry body", N);
1330 Analyze (Entry_Name);
1332 if Etype (Entry_Name) = Any_Type then
1336 if Nkind (Entry_Name) = N_Selected_Component then
1337 Target_Obj := Prefix (Entry_Name);
1338 Entry_Name := Selector_Name (Entry_Name);
1341 -- If an explicit target object is given then we have to check the
1342 -- restrictions of 9.5.4(6).
1344 if Present (Target_Obj) then
1346 -- Locate containing concurrent unit and determine enclosing entry
1347 -- body or outermost enclosing accept statement within the unit.
1350 for S in reverse 0 .. Scope_Stack.Last loop
1351 Req_Scope := Scope_Stack.Table (S).Entity;
1353 exit when Ekind (Req_Scope) in Task_Kind
1354 or else Ekind (Req_Scope) in Protected_Kind;
1356 if Is_Entry (Req_Scope) then
1357 Outer_Ent := Req_Scope;
1361 pragma Assert (Present (Outer_Ent));
1363 -- Check that the accessibility level of the target object is not
1364 -- greater or equal to the outermost enclosing accept statement (or
1365 -- entry body) unless it is a parameter of the innermost enclosing
1366 -- accept statement (or entry body).
1368 if Object_Access_Level (Target_Obj) >= Scope_Depth (Outer_Ent)
1370 (not Is_Entity_Name (Target_Obj)
1371 or else Ekind (Entity (Target_Obj)) not in Formal_Kind
1372 or else Enclosing /= Scope (Entity (Target_Obj)))
1375 ("target object has invalid level for requeue", Target_Obj);
1379 -- Overloaded case, find right interpretation
1381 if Is_Overloaded (Entry_Name) then
1384 -- Loop over candidate interpretations and filter out any that are
1385 -- not parameterless, are not type conformant, are not entries, or
1386 -- do not come from source.
1388 Get_First_Interp (Entry_Name, I, It);
1389 while Present (It.Nam) loop
1391 -- Note: we test type conformance here, not subtype conformance.
1392 -- Subtype conformance will be tested later on, but it is better
1393 -- for error output in some cases not to do that here.
1395 if (No (First_Formal (It.Nam))
1396 or else (Type_Conformant (Enclosing, It.Nam)))
1397 and then Ekind (It.Nam) = E_Entry
1399 -- Ada 2005 (AI-345): Since protected and task types have
1400 -- primitive entry wrappers, we only consider source entries.
1402 if Comes_From_Source (It.Nam) then
1410 Get_Next_Interp (I, It);
1414 Error_Msg_N ("no entry matches context", N);
1417 elsif Count > 1 then
1418 Error_Msg_N ("ambiguous entry name in requeue", N);
1422 Set_Is_Overloaded (Entry_Name, False);
1423 Set_Entity (Entry_Name, Entry_Id);
1426 -- Non-overloaded cases
1428 -- For the case of a reference to an element of an entry family, the
1429 -- Entry_Name is an indexed component.
1431 elsif Nkind (Entry_Name) = N_Indexed_Component then
1433 -- Requeue to an entry out of the body
1435 if Nkind (Prefix (Entry_Name)) = N_Selected_Component then
1436 Entry_Id := Entity (Selector_Name (Prefix (Entry_Name)));
1438 -- Requeue from within the body itself
1440 elsif Nkind (Prefix (Entry_Name)) = N_Identifier then
1441 Entry_Id := Entity (Prefix (Entry_Name));
1444 Error_Msg_N ("invalid entry_name specified", N);
1448 -- If we had a requeue of the form REQUEUE A (B), then the parser
1449 -- accepted it (because it could have been a requeue on an entry index.
1450 -- If A turns out not to be an entry family, then the analysis of A (B)
1451 -- turned it into a function call.
1453 elsif Nkind (Entry_Name) = N_Function_Call then
1455 ("arguments not allowed in requeue statement",
1456 First (Parameter_Associations (Entry_Name)));
1459 -- Normal case of no entry family, no argument
1462 Entry_Id := Entity (Entry_Name);
1465 -- Ada 2012 (AI05-0030): Potential dispatching requeue statement. The
1466 -- target type must be a concurrent interface class-wide type and the
1467 -- target must be a procedure, flagged by pragma Implemented.
1470 Ada_Version >= Ada_2012
1471 and then Present (Target_Obj)
1472 and then Is_Class_Wide_Type (Etype (Target_Obj))
1473 and then Is_Concurrent_Interface (Etype (Target_Obj))
1474 and then Ekind (Entry_Id) = E_Procedure
1475 and then Has_Rep_Pragma (Entry_Id, Name_Implemented);
1477 -- Resolve entry, and check that it is subtype conformant with the
1478 -- enclosing construct if this construct has formals (RM 9.5.4(5)).
1479 -- Ada 2005 (AI05-0030): Do not emit an error for this specific case.
1481 if not Is_Entry (Entry_Id)
1482 and then not Is_Disp_Req
1484 Error_Msg_N ("expect entry name in requeue statement", Name (N));
1486 elsif Ekind (Entry_Id) = E_Entry_Family
1487 and then Nkind (Entry_Name) /= N_Indexed_Component
1489 Error_Msg_N ("missing index for entry family component", Name (N));
1492 Resolve_Entry (Name (N));
1493 Generate_Reference (Entry_Id, Entry_Name);
1495 if Present (First_Formal (Entry_Id)) then
1496 if VM_Target = JVM_Target then
1498 ("arguments unsupported in requeue statement",
1499 First_Formal (Entry_Id));
1503 -- Ada 2012 (AI05-0030): Perform type conformance after skipping
1504 -- the first parameter of Entry_Id since it is the interface
1505 -- controlling formal.
1507 if Ada_Version >= Ada_2012
1508 and then Is_Disp_Req
1511 Enclosing_Formal : Entity_Id;
1512 Target_Formal : Entity_Id;
1515 Enclosing_Formal := First_Formal (Enclosing);
1516 Target_Formal := Next_Formal (First_Formal (Entry_Id));
1517 while Present (Enclosing_Formal)
1518 and then Present (Target_Formal)
1520 if not Conforming_Types
1521 (T1 => Etype (Enclosing_Formal),
1522 T2 => Etype (Target_Formal),
1523 Ctype => Subtype_Conformant)
1525 Error_Msg_Node_2 := Target_Formal;
1527 ("formal & is not subtype conformant with &" &
1528 "in dispatching requeue", N, Enclosing_Formal);
1531 Next_Formal (Enclosing_Formal);
1532 Next_Formal (Target_Formal);
1536 Check_Subtype_Conformant (Enclosing, Entry_Id, Name (N));
1539 -- Processing for parameters accessed by the requeue
1545 Ent := First_Formal (Enclosing);
1546 while Present (Ent) loop
1548 -- For OUT or IN OUT parameter, the effect of the requeue is
1549 -- to assign the parameter a value on exit from the requeued
1550 -- body, so we can set it as source assigned. We also clear
1551 -- the Is_True_Constant indication. We do not need to clear
1552 -- Current_Value, since the effect of the requeue is to
1553 -- perform an unconditional goto so that any further
1554 -- references will not occur anyway.
1556 if Ekind_In (Ent, E_Out_Parameter, E_In_Out_Parameter) then
1557 Set_Never_Set_In_Source (Ent, False);
1558 Set_Is_True_Constant (Ent, False);
1561 -- For all parameters, the requeue acts as a reference,
1562 -- since the value of the parameter is passed to the new
1563 -- entry, so we want to suppress unreferenced warnings.
1565 Set_Referenced (Ent);
1571 end Analyze_Requeue;
1573 ------------------------------
1574 -- Analyze_Selective_Accept --
1575 ------------------------------
1577 procedure Analyze_Selective_Accept (N : Node_Id) is
1578 Alts : constant List_Id := Select_Alternatives (N);
1581 Accept_Present : Boolean := False;
1582 Terminate_Present : Boolean := False;
1583 Delay_Present : Boolean := False;
1584 Relative_Present : Boolean := False;
1585 Alt_Count : Uint := Uint_0;
1588 Tasking_Used := True;
1589 Check_SPARK_Restriction ("select statement is not allowed", N);
1590 Check_Restriction (No_Select_Statements, N);
1592 -- Loop to analyze alternatives
1594 Alt := First (Alts);
1595 while Present (Alt) loop
1596 Alt_Count := Alt_Count + 1;
1599 if Nkind (Alt) = N_Delay_Alternative then
1600 if Delay_Present then
1602 if Relative_Present /=
1603 (Nkind (Delay_Statement (Alt)) = N_Delay_Relative_Statement)
1606 ("delay_until and delay_relative alternatives ", Alt);
1608 ("\cannot appear in the same selective_wait", Alt);
1612 Delay_Present := True;
1614 Nkind (Delay_Statement (Alt)) = N_Delay_Relative_Statement;
1617 elsif Nkind (Alt) = N_Terminate_Alternative then
1618 if Terminate_Present then
1619 Error_Msg_N ("only one terminate alternative allowed", N);
1621 Terminate_Present := True;
1622 Check_Restriction (No_Terminate_Alternatives, N);
1625 elsif Nkind (Alt) = N_Accept_Alternative then
1626 Accept_Present := True;
1628 -- Check for duplicate accept
1632 Stm : constant Node_Id := Accept_Statement (Alt);
1633 EDN : constant Node_Id := Entry_Direct_Name (Stm);
1637 if Nkind (EDN) = N_Identifier
1638 and then No (Condition (Alt))
1639 and then Present (Entity (EDN)) -- defend against junk
1640 and then Ekind (Entity (EDN)) = E_Entry
1642 Ent := Entity (EDN);
1644 Alt1 := First (Alts);
1645 while Alt1 /= Alt loop
1646 if Nkind (Alt1) = N_Accept_Alternative
1647 and then No (Condition (Alt1))
1650 Stm1 : constant Node_Id := Accept_Statement (Alt1);
1651 EDN1 : constant Node_Id := Entry_Direct_Name (Stm1);
1654 if Nkind (EDN1) = N_Identifier then
1655 if Entity (EDN1) = Ent then
1656 Error_Msg_Sloc := Sloc (Stm1);
1658 ("?accept duplicates one on line#", Stm);
1674 Check_Restriction (Max_Select_Alternatives, N, Alt_Count);
1675 Check_Potentially_Blocking_Operation (N);
1677 if Terminate_Present and Delay_Present then
1678 Error_Msg_N ("at most one of terminate or delay alternative", N);
1680 elsif not Accept_Present then
1682 ("select must contain at least one accept alternative", N);
1685 if Present (Else_Statements (N)) then
1686 if Terminate_Present or Delay_Present then
1687 Error_Msg_N ("else part not allowed with other alternatives", N);
1690 Analyze_Statements (Else_Statements (N));
1692 end Analyze_Selective_Accept;
1694 ------------------------------------------
1695 -- Analyze_Single_Protected_Declaration --
1696 ------------------------------------------
1698 procedure Analyze_Single_Protected_Declaration (N : Node_Id) is
1699 Loc : constant Source_Ptr := Sloc (N);
1700 Id : constant Node_Id := Defining_Identifier (N);
1704 O_Name : constant Entity_Id := Id;
1707 Generate_Definition (Id);
1708 Tasking_Used := True;
1710 -- The node is rewritten as a protected type declaration, in exact
1711 -- analogy with what is done with single tasks.
1714 Make_Defining_Identifier (Sloc (Id),
1715 New_External_Name (Chars (Id), 'T'));
1718 Make_Protected_Type_Declaration (Loc,
1719 Defining_Identifier => T,
1720 Protected_Definition => Relocate_Node (Protected_Definition (N)),
1721 Interface_List => Interface_List (N));
1724 Make_Object_Declaration (Loc,
1725 Defining_Identifier => O_Name,
1726 Object_Definition => Make_Identifier (Loc, Chars (T)));
1728 Rewrite (N, T_Decl);
1729 Insert_After (N, O_Decl);
1730 Mark_Rewrite_Insertion (O_Decl);
1732 -- Enter names of type and object before analysis, because the name of
1733 -- the object may be used in its own body.
1736 Set_Ekind (T, E_Protected_Type);
1739 Enter_Name (O_Name);
1740 Set_Ekind (O_Name, E_Variable);
1741 Set_Etype (O_Name, T);
1743 -- Instead of calling Analyze on the new node, call the proper analysis
1744 -- procedure directly. Otherwise the node would be expanded twice, with
1745 -- disastrous result.
1747 Analyze_Protected_Type_Declaration (N);
1749 if Has_Aspects (N) then
1750 Analyze_Aspect_Specifications (N, Id);
1752 end Analyze_Single_Protected_Declaration;
1754 -------------------------------------
1755 -- Analyze_Single_Task_Declaration --
1756 -------------------------------------
1758 procedure Analyze_Single_Task_Declaration (N : Node_Id) is
1759 Loc : constant Source_Ptr := Sloc (N);
1760 Id : constant Node_Id := Defining_Identifier (N);
1764 O_Name : constant Entity_Id := Id;
1767 Generate_Definition (Id);
1768 Tasking_Used := True;
1770 -- The node is rewritten as a task type declaration, followed by an
1771 -- object declaration of that anonymous task type.
1774 Make_Defining_Identifier (Sloc (Id),
1775 New_External_Name (Chars (Id), Suffix => "TK"));
1778 Make_Task_Type_Declaration (Loc,
1779 Defining_Identifier => T,
1780 Task_Definition => Relocate_Node (Task_Definition (N)),
1781 Interface_List => Interface_List (N));
1783 -- We use the original defining identifier of the single task in the
1784 -- generated object declaration, so that debugging information can
1785 -- be attached to it when compiling with -gnatD. The parent of the
1786 -- entity is the new object declaration. The single_task_declaration
1787 -- is not used further in semantics or code generation, but is scanned
1788 -- when generating debug information, and therefore needs the updated
1789 -- Sloc information for the entity (see Sprint). Aspect specifications
1790 -- are moved from the single task node to the object declaration node.
1793 Make_Object_Declaration (Loc,
1794 Defining_Identifier => O_Name,
1795 Object_Definition => Make_Identifier (Loc, Chars (T)));
1797 Rewrite (N, T_Decl);
1798 Insert_After (N, O_Decl);
1799 Mark_Rewrite_Insertion (O_Decl);
1801 -- Enter names of type and object before analysis, because the name of
1802 -- the object may be used in its own body.
1805 Set_Ekind (T, E_Task_Type);
1808 Enter_Name (O_Name);
1809 Set_Ekind (O_Name, E_Variable);
1810 Set_Etype (O_Name, T);
1812 -- Instead of calling Analyze on the new node, call the proper analysis
1813 -- procedure directly. Otherwise the node would be expanded twice, with
1814 -- disastrous result.
1816 Analyze_Task_Type_Declaration (N);
1818 if Has_Aspects (N) then
1819 Analyze_Aspect_Specifications (N, Id);
1821 end Analyze_Single_Task_Declaration;
1823 -----------------------
1824 -- Analyze_Task_Body --
1825 -----------------------
1827 procedure Analyze_Task_Body (N : Node_Id) is
1828 Body_Id : constant Entity_Id := Defining_Identifier (N);
1829 Decls : constant List_Id := Declarations (N);
1830 HSS : constant Node_Id := Handled_Statement_Sequence (N);
1833 Spec_Id : Entity_Id;
1834 -- This is initially the entity of the task or task type involved, but
1835 -- is replaced by the task type always in the case of a single task
1836 -- declaration, since this is the proper scope to be used.
1839 -- This is the entity of the task or task type, and is the entity used
1840 -- for cross-reference purposes (it differs from Spec_Id in the case of
1841 -- a single task, since Spec_Id is set to the task type)
1844 Tasking_Used := True;
1845 Set_Ekind (Body_Id, E_Task_Body);
1846 Set_Scope (Body_Id, Current_Scope);
1847 Spec_Id := Find_Concurrent_Spec (Body_Id);
1849 -- The spec is either a task type declaration, or a single task
1850 -- declaration for which we have created an anonymous type.
1852 if Present (Spec_Id)
1853 and then Ekind (Spec_Id) = E_Task_Type
1857 elsif Present (Spec_Id)
1858 and then Ekind (Etype (Spec_Id)) = E_Task_Type
1859 and then not Comes_From_Source (Etype (Spec_Id))
1864 Error_Msg_N ("missing specification for task body", Body_Id);
1868 if Has_Completion (Spec_Id)
1869 and then Present (Corresponding_Body (Parent (Spec_Id)))
1871 if Nkind (Parent (Spec_Id)) = N_Task_Type_Declaration then
1872 Error_Msg_NE ("duplicate body for task type&", N, Spec_Id);
1875 Error_Msg_NE ("duplicate body for task&", N, Spec_Id);
1880 Generate_Reference (Ref_Id, Body_Id, 'b', Set_Ref => False);
1881 Style.Check_Identifier (Body_Id, Spec_Id);
1883 -- Deal with case of body of single task (anonymous type was created)
1885 if Ekind (Spec_Id) = E_Variable then
1886 Spec_Id := Etype (Spec_Id);
1889 Push_Scope (Spec_Id);
1890 Set_Corresponding_Spec (N, Spec_Id);
1891 Set_Corresponding_Body (Parent (Spec_Id), Body_Id);
1892 Set_Has_Completion (Spec_Id);
1893 Install_Declarations (Spec_Id);
1894 Last_E := Last_Entity (Spec_Id);
1896 Analyze_Declarations (Decls);
1897 Inspect_Deferred_Constant_Completion (Decls);
1899 -- For visibility purposes, all entities in the body are private. Set
1900 -- First_Private_Entity accordingly, if there was no private part in the
1901 -- protected declaration.
1903 if No (First_Private_Entity (Spec_Id)) then
1904 if Present (Last_E) then
1905 Set_First_Private_Entity (Spec_Id, Next_Entity (Last_E));
1907 Set_First_Private_Entity (Spec_Id, First_Entity (Spec_Id));
1911 -- Mark all handlers as not suitable for local raise optimization,
1912 -- since this optimization causes difficulties in a task context.
1914 if Present (Exception_Handlers (HSS)) then
1918 Handlr := First (Exception_Handlers (HSS));
1919 while Present (Handlr) loop
1920 Set_Local_Raise_Not_OK (Handlr);
1926 -- Now go ahead and complete analysis of the task body
1929 Check_Completion (Body_Id);
1930 Check_References (Body_Id);
1931 Check_References (Spec_Id);
1933 -- Check for entries with no corresponding accept
1939 Ent := First_Entity (Spec_Id);
1940 while Present (Ent) loop
1942 and then not Entry_Accepted (Ent)
1943 and then Comes_From_Source (Ent)
1945 Error_Msg_NE ("no accept for entry &?", N, Ent);
1952 Process_End_Label (HSS, 't', Ref_Id);
1954 end Analyze_Task_Body;
1956 -----------------------------
1957 -- Analyze_Task_Definition --
1958 -----------------------------
1960 procedure Analyze_Task_Definition (N : Node_Id) is
1964 Tasking_Used := True;
1965 Check_SPARK_Restriction ("task definition is not allowed", N);
1967 if Present (Visible_Declarations (N)) then
1968 Analyze_Declarations (Visible_Declarations (N));
1971 if Present (Private_Declarations (N)) then
1972 L := Last_Entity (Current_Scope);
1973 Analyze_Declarations (Private_Declarations (N));
1976 Set_First_Private_Entity
1977 (Current_Scope, Next_Entity (L));
1979 Set_First_Private_Entity
1980 (Current_Scope, First_Entity (Current_Scope));
1984 Check_Max_Entries (N, Max_Task_Entries);
1985 Process_End_Label (N, 'e', Current_Scope);
1986 end Analyze_Task_Definition;
1988 -----------------------------------
1989 -- Analyze_Task_Type_Declaration --
1990 -----------------------------------
1992 procedure Analyze_Task_Type_Declaration (N : Node_Id) is
1993 Def_Id : constant Entity_Id := Defining_Identifier (N);
1997 Check_Restriction (No_Tasking, N);
1998 Tasking_Used := True;
1999 T := Find_Type_Name (N);
2000 Generate_Definition (T);
2002 -- In the case of an incomplete type, use the full view, unless it's not
2003 -- present (as can occur for an incomplete view from a limited with).
2004 -- Initialize the Corresponding_Record_Type (which overlays the Private
2005 -- Dependents field of the incomplete view).
2007 if Ekind (T) = E_Incomplete_Type then
2008 if Present (Full_View (T)) then
2010 Set_Completion_Referenced (T);
2013 Set_Ekind (T, E_Task_Type);
2014 Set_Corresponding_Record_Type (T, Empty);
2018 Set_Ekind (T, E_Task_Type);
2019 Set_Is_First_Subtype (T, True);
2020 Set_Has_Task (T, True);
2021 Init_Size_Align (T);
2023 Set_Has_Delayed_Freeze (T, True);
2024 Set_Stored_Constraint (T, No_Elist);
2027 if Ada_Version >= Ada_2005 then
2028 Check_Interfaces (N, T);
2031 if Present (Discriminant_Specifications (N)) then
2032 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
2033 Error_Msg_N ("(Ada 83) task discriminant not allowed!", N);
2036 if Has_Discriminants (T) then
2038 -- Install discriminants. Also, verify conformance of
2039 -- discriminants of previous and current view. ???
2041 Install_Declarations (T);
2043 Process_Discriminants (N);
2047 Set_Is_Constrained (T, not Has_Discriminants (T));
2049 if Present (Task_Definition (N)) then
2050 Analyze_Task_Definition (Task_Definition (N));
2053 -- In the case where the task type is declared at a nested level and the
2054 -- No_Task_Hierarchy restriction applies, issue a warning that objects
2055 -- of the type will violate the restriction.
2057 if Restriction_Check_Required (No_Task_Hierarchy)
2058 and then not Is_Library_Level_Entity (T)
2059 and then Comes_From_Source (T)
2061 Error_Msg_Sloc := Restrictions_Loc (No_Task_Hierarchy);
2063 if Error_Msg_Sloc = No_Location then
2065 ("objects of this type will violate `No_Task_Hierarchy`?", N);
2068 ("objects of this type will violate `No_Task_Hierarchy`?#", N);
2074 -- Case of a completion of a private declaration
2077 and then Is_Private_Type (Def_Id)
2079 -- Deal with preelaborable initialization. Note that this processing
2080 -- is done by Process_Full_View, but as can be seen below, in this
2081 -- case the call to Process_Full_View is skipped if any serious
2082 -- errors have occurred, and we don't want to lose this check.
2084 if Known_To_Have_Preelab_Init (Def_Id) then
2085 Set_Must_Have_Preelab_Init (T);
2088 -- Create corresponding record now, because some private dependents
2089 -- may be subtypes of the partial view.
2091 -- Skip if errors are present, to prevent cascaded messages
2093 if Serious_Errors_Detected = 0
2095 -- Also skip if expander is not active
2097 and then Full_Expander_Active
2099 Expand_N_Task_Type_Declaration (N);
2100 Process_Full_View (N, T, Def_Id);
2104 if Has_Aspects (N) then
2105 Analyze_Aspect_Specifications (N, Def_Id);
2107 end Analyze_Task_Type_Declaration;
2109 -----------------------------------
2110 -- Analyze_Terminate_Alternative --
2111 -----------------------------------
2113 procedure Analyze_Terminate_Alternative (N : Node_Id) is
2115 Tasking_Used := True;
2117 if Present (Pragmas_Before (N)) then
2118 Analyze_List (Pragmas_Before (N));
2121 if Present (Condition (N)) then
2122 Analyze_And_Resolve (Condition (N), Any_Boolean);
2124 end Analyze_Terminate_Alternative;
2126 ------------------------------
2127 -- Analyze_Timed_Entry_Call --
2128 ------------------------------
2130 procedure Analyze_Timed_Entry_Call (N : Node_Id) is
2131 Trigger : constant Node_Id :=
2132 Entry_Call_Statement (Entry_Call_Alternative (N));
2133 Is_Disp_Select : Boolean := False;
2136 Tasking_Used := True;
2137 Check_SPARK_Restriction ("select statement is not allowed", N);
2138 Check_Restriction (No_Select_Statements, N);
2140 -- Ada 2005 (AI-345): The trigger may be a dispatching call
2142 if Ada_Version >= Ada_2005 then
2144 Check_Triggering_Statement (Trigger, N, Is_Disp_Select);
2147 -- Postpone the analysis of the statements till expansion. Analyze only
2148 -- if the expander is disabled in order to catch any semantic errors.
2150 if Is_Disp_Select then
2151 if not Expander_Active then
2152 Analyze (Entry_Call_Alternative (N));
2153 Analyze (Delay_Alternative (N));
2156 -- Regular select analysis
2159 Analyze (Entry_Call_Alternative (N));
2160 Analyze (Delay_Alternative (N));
2162 end Analyze_Timed_Entry_Call;
2164 ------------------------------------
2165 -- Analyze_Triggering_Alternative --
2166 ------------------------------------
2168 procedure Analyze_Triggering_Alternative (N : Node_Id) is
2169 Trigger : constant Node_Id := Triggering_Statement (N);
2172 Tasking_Used := True;
2174 if Present (Pragmas_Before (N)) then
2175 Analyze_List (Pragmas_Before (N));
2180 if Comes_From_Source (Trigger)
2181 and then Nkind (Trigger) not in N_Delay_Statement
2182 and then Nkind (Trigger) /= N_Entry_Call_Statement
2184 if Ada_Version < Ada_2005 then
2186 ("triggering statement must be delay or entry call", Trigger);
2188 -- Ada 2005 (AI-345): If a procedure_call_statement is used for a
2189 -- procedure_or_entry_call, the procedure_name or procedure_prefix
2190 -- of the procedure_call_statement shall denote an entry renamed by a
2191 -- procedure, or (a view of) a primitive subprogram of a limited
2192 -- interface whose first parameter is a controlling parameter.
2194 elsif Nkind (Trigger) = N_Procedure_Call_Statement
2195 and then not Is_Renamed_Entry (Entity (Name (Trigger)))
2196 and then not Is_Controlling_Limited_Procedure
2197 (Entity (Name (Trigger)))
2199 Error_Msg_N ("triggering statement must be delay, procedure " &
2200 "or entry call", Trigger);
2204 if Is_Non_Empty_List (Statements (N)) then
2205 Analyze_Statements (Statements (N));
2207 end Analyze_Triggering_Alternative;
2209 -----------------------
2210 -- Check_Max_Entries --
2211 -----------------------
2213 procedure Check_Max_Entries (D : Node_Id; R : All_Parameter_Restrictions) is
2216 procedure Count (L : List_Id);
2217 -- Count entries in given declaration list
2223 procedure Count (L : List_Id) is
2232 while Present (D) loop
2233 if Nkind (D) = N_Entry_Declaration then
2235 DSD : constant Node_Id :=
2236 Discrete_Subtype_Definition (D);
2239 -- If not an entry family, then just one entry
2242 Ecount := Ecount + 1;
2244 -- If entry family with static bounds, count entries
2246 elsif Is_OK_Static_Subtype (Etype (DSD)) then
2248 Lo : constant Uint :=
2250 (Type_Low_Bound (Etype (DSD)));
2251 Hi : constant Uint :=
2253 (Type_High_Bound (Etype (DSD)));
2257 Ecount := Ecount + Hi - Lo + 1;
2261 -- Entry family with non-static bounds
2264 -- Record an unknown count restriction, and if the
2265 -- restriction is active, post a message or warning.
2267 Check_Restriction (R, D);
2276 -- Start of processing for Check_Max_Entries
2280 Count (Visible_Declarations (D));
2281 Count (Private_Declarations (D));
2284 Check_Restriction (R, D, Ecount);
2286 end Check_Max_Entries;
2288 ----------------------
2289 -- Check_Interfaces --
2290 ----------------------
2292 procedure Check_Interfaces (N : Node_Id; T : Entity_Id) is
2294 Iface_Typ : Entity_Id;
2298 (Nkind_In (N, N_Protected_Type_Declaration, N_Task_Type_Declaration));
2300 if Present (Interface_List (N)) then
2301 Set_Is_Tagged_Type (T);
2303 Iface := First (Interface_List (N));
2304 while Present (Iface) loop
2305 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
2307 if not Is_Interface (Iface_Typ) then
2309 ("(Ada 2005) & must be an interface", Iface, Iface_Typ);
2312 -- Ada 2005 (AI-251): "The declaration of a specific descendant
2313 -- of an interface type freezes the interface type" RM 13.14.
2315 Freeze_Before (N, Etype (Iface));
2317 if Nkind (N) = N_Protected_Type_Declaration then
2319 -- Ada 2005 (AI-345): Protected types can only implement
2320 -- limited, synchronized, or protected interfaces (note that
2321 -- the predicate Is_Limited_Interface includes synchronized
2322 -- and protected interfaces).
2324 if Is_Task_Interface (Iface_Typ) then
2325 Error_Msg_N ("(Ada 2005) protected type cannot implement "
2326 & "a task interface", Iface);
2328 elsif not Is_Limited_Interface (Iface_Typ) then
2329 Error_Msg_N ("(Ada 2005) protected type cannot implement "
2330 & "a non-limited interface", Iface);
2333 else pragma Assert (Nkind (N) = N_Task_Type_Declaration);
2335 -- Ada 2005 (AI-345): Task types can only implement limited,
2336 -- synchronized, or task interfaces (note that the predicate
2337 -- Is_Limited_Interface includes synchronized and task
2340 if Is_Protected_Interface (Iface_Typ) then
2341 Error_Msg_N ("(Ada 2005) task type cannot implement a " &
2342 "protected interface", Iface);
2344 elsif not Is_Limited_Interface (Iface_Typ) then
2345 Error_Msg_N ("(Ada 2005) task type cannot implement a " &
2346 "non-limited interface", Iface);
2355 if not Has_Private_Declaration (T) then
2359 -- Additional checks on full-types associated with private type
2360 -- declarations. Search for the private type declaration.
2363 Full_T_Ifaces : Elist_Id;
2366 Priv_T_Ifaces : Elist_Id;
2369 Priv_T := First_Entity (Scope (T));
2371 pragma Assert (Present (Priv_T));
2373 if Is_Type (Priv_T) and then Present (Full_View (Priv_T)) then
2374 exit when Full_View (Priv_T) = T;
2377 Next_Entity (Priv_T);
2380 -- In case of synchronized types covering interfaces the private type
2381 -- declaration must be limited.
2383 if Present (Interface_List (N))
2384 and then not Is_Limited_Type (Priv_T)
2386 Error_Msg_Sloc := Sloc (Priv_T);
2387 Error_Msg_N ("(Ada 2005) limited type declaration expected for " &
2388 "private type#", T);
2391 -- RM 7.3 (7.1/2): If the full view has a partial view that is
2392 -- tagged then check RM 7.3 subsidiary rules.
2394 if Is_Tagged_Type (Priv_T)
2395 and then not Error_Posted (N)
2397 -- RM 7.3 (7.2/2): The partial view shall be a synchronized tagged
2398 -- type if and only if the full type is a synchronized tagged type
2400 if Is_Synchronized_Tagged_Type (Priv_T)
2401 and then not Is_Synchronized_Tagged_Type (T)
2404 ("(Ada 2005) full view must be a synchronized tagged " &
2405 "type (RM 7.3 (7.2/2))", Priv_T);
2407 elsif Is_Synchronized_Tagged_Type (T)
2408 and then not Is_Synchronized_Tagged_Type (Priv_T)
2411 ("(Ada 2005) partial view must be a synchronized tagged " &
2412 "type (RM 7.3 (7.2/2))", T);
2415 -- RM 7.3 (7.3/2): The partial view shall be a descendant of an
2416 -- interface type if and only if the full type is descendant of
2417 -- the interface type.
2419 if Present (Interface_List (N))
2420 or else (Is_Tagged_Type (Priv_T)
2421 and then Has_Interfaces
2422 (Priv_T, Use_Full_View => False))
2424 if Is_Tagged_Type (Priv_T) then
2426 (Priv_T, Priv_T_Ifaces, Use_Full_View => False);
2429 if Is_Tagged_Type (T) then
2430 Collect_Interfaces (T, Full_T_Ifaces);
2433 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
2435 if Present (Iface) then
2437 ("interface & not implemented by full type " &
2438 "(RM-2005 7.3 (7.3/2))", Priv_T, Iface);
2441 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
2443 if Present (Iface) then
2445 ("interface & not implemented by partial " &
2446 "view (RM-2005 7.3 (7.3/2))", T, Iface);
2451 end Check_Interfaces;
2453 --------------------------------
2454 -- Check_Triggering_Statement --
2455 --------------------------------
2457 procedure Check_Triggering_Statement
2459 Error_Node : Node_Id;
2460 Is_Dispatching : out Boolean)
2465 Is_Dispatching := False;
2467 -- It is not possible to have a dispatching trigger if we are not in
2470 if Ada_Version >= Ada_2005
2471 and then Nkind (Trigger) = N_Procedure_Call_Statement
2472 and then Present (Parameter_Associations (Trigger))
2474 Param := First (Parameter_Associations (Trigger));
2476 if Is_Controlling_Actual (Param)
2477 and then Is_Interface (Etype (Param))
2479 if Is_Limited_Record (Etype (Param)) then
2480 Is_Dispatching := True;
2483 ("dispatching operation of limited or synchronized " &
2484 "interface required (RM 9.7.2(3))!", Error_Node);
2488 end Check_Triggering_Statement;
2490 --------------------------
2491 -- Find_Concurrent_Spec --
2492 --------------------------
2494 function Find_Concurrent_Spec (Body_Id : Entity_Id) return Entity_Id is
2495 Spec_Id : Entity_Id := Current_Entity_In_Scope (Body_Id);
2498 -- The type may have been given by an incomplete type declaration.
2499 -- Find full view now.
2501 if Present (Spec_Id) and then Ekind (Spec_Id) = E_Incomplete_Type then
2502 Spec_Id := Full_View (Spec_Id);
2506 end Find_Concurrent_Spec;
2508 --------------------------
2509 -- Install_Declarations --
2510 --------------------------
2512 procedure Install_Declarations (Spec : Entity_Id) is
2516 E := First_Entity (Spec);
2517 while Present (E) loop
2518 Prev := Current_Entity (E);
2519 Set_Current_Entity (E);
2520 Set_Is_Immediately_Visible (E);
2521 Set_Homonym (E, Prev);
2524 end Install_Declarations;