1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2010, 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_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 Targparm; use Targparm;
57 with Tbuild; use Tbuild;
58 with Uintp; use Uintp;
60 package body Sem_Ch9 is
62 -----------------------
63 -- Local Subprograms --
64 -----------------------
66 procedure Check_Max_Entries (D : Node_Id; R : All_Parameter_Restrictions);
67 -- Given either a protected definition or a task definition in D, check
68 -- the corresponding restriction parameter identifier R, and if it is set,
69 -- count the entries (checking the static requirement), and compare with
72 procedure Check_Interfaces (N : Node_Id; T : Entity_Id);
73 -- N is an N_Protected_Type_Declaration or N_Task_Type_Declaration node.
74 -- Complete decoration of T and check legality of the covered interfaces.
76 procedure Check_Triggering_Statement
79 Is_Dispatching : out Boolean);
80 -- Examine the triggering statement of a select statement, conditional or
81 -- timed entry call. If Trigger is a dispatching call, return its status
82 -- in Is_Dispatching and check whether the primitive belongs to a limited
83 -- interface. If it does not, emit an error at Error_Node.
85 function Find_Concurrent_Spec (Body_Id : Entity_Id) return Entity_Id;
86 -- Find entity in corresponding task or protected declaration. Use full
87 -- view if first declaration was for an incomplete type.
89 procedure Install_Declarations (Spec : Entity_Id);
90 -- Utility to make visible in corresponding body the entities defined in
91 -- task, protected type declaration, or entry declaration.
93 -----------------------------
94 -- Analyze_Abort_Statement --
95 -----------------------------
97 procedure Analyze_Abort_Statement (N : Node_Id) is
101 Tasking_Used := True;
102 T_Name := First (Names (N));
103 while Present (T_Name) loop
106 if Is_Task_Type (Etype (T_Name))
107 or else (Ada_Version >= Ada_05
108 and then Ekind (Etype (T_Name)) = E_Class_Wide_Type
109 and then Is_Interface (Etype (T_Name))
110 and then Is_Task_Interface (Etype (T_Name)))
114 if Ada_Version >= Ada_05 then
115 Error_Msg_N ("expect task name or task interface class-wide "
116 & "object for ABORT", T_Name);
118 Error_Msg_N ("expect task name for ABORT", T_Name);
127 Check_Restriction (No_Abort_Statements, N);
128 Check_Potentially_Blocking_Operation (N);
129 end Analyze_Abort_Statement;
131 --------------------------------
132 -- Analyze_Accept_Alternative --
133 --------------------------------
135 procedure Analyze_Accept_Alternative (N : Node_Id) is
137 Tasking_Used := True;
139 if Present (Pragmas_Before (N)) then
140 Analyze_List (Pragmas_Before (N));
143 if Present (Condition (N)) then
144 Analyze_And_Resolve (Condition (N), Any_Boolean);
147 Analyze (Accept_Statement (N));
149 if Is_Non_Empty_List (Statements (N)) then
150 Analyze_Statements (Statements (N));
152 end Analyze_Accept_Alternative;
154 ------------------------------
155 -- Analyze_Accept_Statement --
156 ------------------------------
158 procedure Analyze_Accept_Statement (N : Node_Id) is
159 Nam : constant Entity_Id := Entry_Direct_Name (N);
160 Formals : constant List_Id := Parameter_Specifications (N);
161 Index : constant Node_Id := Entry_Index (N);
162 Stats : constant Node_Id := Handled_Statement_Sequence (N);
163 Accept_Id : Entity_Id;
164 Entry_Nam : Entity_Id;
167 Task_Nam : Entity_Id;
170 Tasking_Used := True;
172 -- Entry name is initialized to Any_Id. It should get reset to the
173 -- matching entry entity. An error is signalled if it is not reset.
177 for J in reverse 0 .. Scope_Stack.Last loop
178 Task_Nam := Scope_Stack.Table (J).Entity;
179 exit when Ekind (Etype (Task_Nam)) = E_Task_Type;
180 Kind := Ekind (Task_Nam);
182 if Kind /= E_Block and then Kind /= E_Loop
183 and then not Is_Entry (Task_Nam)
185 Error_Msg_N ("enclosing body of accept must be a task", N);
190 if Ekind (Etype (Task_Nam)) /= E_Task_Type then
191 Error_Msg_N ("invalid context for accept statement", N);
195 -- In order to process the parameters, we create a defining
196 -- identifier that can be used as the name of the scope. The
197 -- name of the accept statement itself is not a defining identifier,
198 -- and we cannot use its name directly because the task may have
199 -- any number of accept statements for the same entry.
201 if Present (Index) then
202 Accept_Id := New_Internal_Entity
203 (E_Entry_Family, Current_Scope, Sloc (N), 'E');
205 Accept_Id := New_Internal_Entity
206 (E_Entry, Current_Scope, Sloc (N), 'E');
209 Set_Etype (Accept_Id, Standard_Void_Type);
210 Set_Accept_Address (Accept_Id, New_Elmt_List);
212 if Present (Formals) then
213 Push_Scope (Accept_Id);
214 Process_Formals (Formals, N);
215 Create_Extra_Formals (Accept_Id);
219 -- We set the default expressions processed flag because we don't need
220 -- default expression functions. This is really more like body entity
221 -- than a spec entity anyway.
223 Set_Default_Expressions_Processed (Accept_Id);
225 E := First_Entity (Etype (Task_Nam));
226 while Present (E) loop
227 if Chars (E) = Chars (Nam)
228 and then (Ekind (E) = Ekind (Accept_Id))
229 and then Type_Conformant (Accept_Id, E)
238 if Entry_Nam = Any_Id then
239 Error_Msg_N ("no entry declaration matches accept statement", N);
242 Set_Entity (Nam, Entry_Nam);
243 Generate_Reference (Entry_Nam, Nam, 'b', Set_Ref => False);
244 Style.Check_Identifier (Nam, Entry_Nam);
247 -- Verify that the entry is not hidden by a procedure declared in the
248 -- current block (pathological but possible).
250 if Current_Scope /= Task_Nam then
255 E1 := First_Entity (Current_Scope);
256 while Present (E1) loop
257 if Ekind (E1) = E_Procedure
258 and then Chars (E1) = Chars (Entry_Nam)
259 and then Type_Conformant (E1, Entry_Nam)
261 Error_Msg_N ("entry name is not visible", N);
269 Set_Convention (Accept_Id, Convention (Entry_Nam));
270 Check_Fully_Conformant (Accept_Id, Entry_Nam, N);
272 for J in reverse 0 .. Scope_Stack.Last loop
273 exit when Task_Nam = Scope_Stack.Table (J).Entity;
275 if Entry_Nam = Scope_Stack.Table (J).Entity then
276 Error_Msg_N ("duplicate accept statement for same entry", N);
287 when N_Task_Body | N_Compilation_Unit =>
289 when N_Asynchronous_Select =>
290 Error_Msg_N ("accept statements are not allowed within" &
291 " an asynchronous select inner" &
292 " to the enclosing task body", N);
300 if Ekind (E) = E_Entry_Family then
302 Error_Msg_N ("missing entry index in accept for entry family", N);
304 Analyze_And_Resolve (Index, Entry_Index_Type (E));
305 Apply_Range_Check (Index, Entry_Index_Type (E));
308 elsif Present (Index) then
309 Error_Msg_N ("invalid entry index in accept for simple entry", N);
312 -- If label declarations present, analyze them. They are declared in the
313 -- enclosing task, but their enclosing scope is the entry itself, so
314 -- that goto's to the label are recognized as local to the accept.
316 if Present (Declarations (N)) then
322 Decl := First (Declarations (N));
323 while Present (Decl) loop
327 (Nkind (Decl) = N_Implicit_Label_Declaration);
329 Id := Defining_Identifier (Decl);
330 Set_Enclosing_Scope (Id, Entry_Nam);
336 -- If statements are present, they must be analyzed in the context of
337 -- the entry, so that references to formals are correctly resolved. We
338 -- also have to add the declarations that are required by the expansion
339 -- of the accept statement in this case if expansion active.
341 -- In the case of a select alternative of a selective accept, the
342 -- expander references the address declaration even if there is no
345 -- We also need to create the renaming declarations for the local
346 -- variables that will replace references to the formals within the
349 Exp_Ch9.Expand_Accept_Declarations (N, Entry_Nam);
351 -- Set Never_Set_In_Source and clear Is_True_Constant/Current_Value
352 -- fields on all entry formals (this loop ignores all other entities).
353 -- Reset Referenced, Referenced_As_xxx and Has_Pragma_Unreferenced as
354 -- well, so that we can post accurate warnings on each accept statement
355 -- for the same entry.
357 E := First_Entity (Entry_Nam);
358 while Present (E) loop
359 if Is_Formal (E) then
360 Set_Never_Set_In_Source (E, True);
361 Set_Is_True_Constant (E, False);
362 Set_Current_Value (E, Empty);
363 Set_Referenced (E, False);
364 Set_Referenced_As_LHS (E, False);
365 Set_Referenced_As_Out_Parameter (E, False);
366 Set_Has_Pragma_Unreferenced (E, False);
372 -- Analyze statements if present
374 if Present (Stats) then
375 Push_Scope (Entry_Nam);
376 Install_Declarations (Entry_Nam);
378 Set_Actual_Subtypes (N, Current_Scope);
381 Process_End_Label (Handled_Statement_Sequence (N), 't', Entry_Nam);
385 -- Some warning checks
387 Check_Potentially_Blocking_Operation (N);
388 Check_References (Entry_Nam, N);
389 Set_Entry_Accepted (Entry_Nam);
390 end Analyze_Accept_Statement;
392 ---------------------------------
393 -- Analyze_Asynchronous_Select --
394 ---------------------------------
396 procedure Analyze_Asynchronous_Select (N : Node_Id) is
397 Is_Disp_Select : Boolean := False;
401 Tasking_Used := True;
402 Check_Restriction (Max_Asynchronous_Select_Nesting, N);
403 Check_Restriction (No_Select_Statements, N);
405 if Ada_Version >= Ada_05 then
406 Trigger := Triggering_Statement (Triggering_Alternative (N));
410 -- Ada 2005 (AI-345): Check for a potential dispatching select
412 Check_Triggering_Statement (Trigger, N, Is_Disp_Select);
415 -- Ada 2005 (AI-345): The expansion of the dispatching asynchronous
416 -- select will have to duplicate the triggering statements. Postpone
417 -- the analysis of the statements till expansion. Analyze only if the
418 -- expander is disabled in order to catch any semantic errors.
420 if Is_Disp_Select then
421 if not Expander_Active then
422 Analyze_Statements (Statements (Abortable_Part (N)));
423 Analyze (Triggering_Alternative (N));
426 -- Analyze the statements. We analyze statements in the abortable part,
427 -- because this is the section that is executed first, and that way our
428 -- remembering of saved values and checks is accurate.
431 Analyze_Statements (Statements (Abortable_Part (N)));
432 Analyze (Triggering_Alternative (N));
434 end Analyze_Asynchronous_Select;
436 ------------------------------------
437 -- Analyze_Conditional_Entry_Call --
438 ------------------------------------
440 procedure Analyze_Conditional_Entry_Call (N : Node_Id) is
441 Trigger : constant Node_Id :=
442 Entry_Call_Statement (Entry_Call_Alternative (N));
443 Is_Disp_Select : Boolean := False;
446 Check_Restriction (No_Select_Statements, N);
447 Tasking_Used := True;
449 -- Ada 2005 (AI-345): The trigger may be a dispatching call
451 if Ada_Version >= Ada_05 then
453 Check_Triggering_Statement (Trigger, N, Is_Disp_Select);
456 if List_Length (Else_Statements (N)) = 1
457 and then Nkind (First (Else_Statements (N))) in N_Delay_Statement
460 ("suspicious form of conditional entry call?!", N);
462 ("\`SELECT OR` may be intended rather than `SELECT ELSE`!", N);
465 -- Postpone the analysis of the statements till expansion. Analyze only
466 -- if the expander is disabled in order to catch any semantic errors.
468 if Is_Disp_Select then
469 if not Expander_Active then
470 Analyze (Entry_Call_Alternative (N));
471 Analyze_Statements (Else_Statements (N));
474 -- Regular select analysis
477 Analyze (Entry_Call_Alternative (N));
478 Analyze_Statements (Else_Statements (N));
480 end Analyze_Conditional_Entry_Call;
482 --------------------------------
483 -- Analyze_Delay_Alternative --
484 --------------------------------
486 procedure Analyze_Delay_Alternative (N : Node_Id) is
491 Tasking_Used := True;
492 Check_Restriction (No_Delay, N);
494 if Present (Pragmas_Before (N)) then
495 Analyze_List (Pragmas_Before (N));
498 if Nkind_In (Parent (N), N_Selective_Accept, N_Timed_Entry_Call) then
499 Expr := Expression (Delay_Statement (N));
501 -- Defer full analysis until the statement is expanded, to insure
502 -- that generated code does not move past the guard. The delay
503 -- expression is only evaluated if the guard is open.
505 if Nkind (Delay_Statement (N)) = N_Delay_Relative_Statement then
506 Preanalyze_And_Resolve (Expr, Standard_Duration);
508 Preanalyze_And_Resolve (Expr);
511 Typ := First_Subtype (Etype (Expr));
513 if Nkind (Delay_Statement (N)) = N_Delay_Until_Statement
514 and then not Is_RTE (Typ, RO_CA_Time)
515 and then not Is_RTE (Typ, RO_RT_Time)
517 Error_Msg_N ("expect Time types for `DELAY UNTIL`", Expr);
520 Check_Restriction (No_Fixed_Point, Expr);
523 Analyze (Delay_Statement (N));
526 if Present (Condition (N)) then
527 Analyze_And_Resolve (Condition (N), Any_Boolean);
530 if Is_Non_Empty_List (Statements (N)) then
531 Analyze_Statements (Statements (N));
533 end Analyze_Delay_Alternative;
535 ----------------------------
536 -- Analyze_Delay_Relative --
537 ----------------------------
539 procedure Analyze_Delay_Relative (N : Node_Id) is
540 E : constant Node_Id := Expression (N);
542 Check_Restriction (No_Relative_Delay, N);
543 Tasking_Used := True;
544 Check_Restriction (No_Delay, N);
545 Check_Potentially_Blocking_Operation (N);
546 Analyze_And_Resolve (E, Standard_Duration);
547 Check_Restriction (No_Fixed_Point, E);
548 end Analyze_Delay_Relative;
550 -------------------------
551 -- Analyze_Delay_Until --
552 -------------------------
554 procedure Analyze_Delay_Until (N : Node_Id) is
555 E : constant Node_Id := Expression (N);
559 Tasking_Used := True;
560 Check_Restriction (No_Delay, N);
561 Check_Potentially_Blocking_Operation (N);
563 Typ := First_Subtype (Etype (E));
565 if not Is_RTE (Typ, RO_CA_Time) and then
566 not Is_RTE (Typ, RO_RT_Time)
568 Error_Msg_N ("expect Time types for `DELAY UNTIL`", E);
570 end Analyze_Delay_Until;
572 ------------------------
573 -- Analyze_Entry_Body --
574 ------------------------
576 procedure Analyze_Entry_Body (N : Node_Id) is
577 Id : constant Entity_Id := Defining_Identifier (N);
578 Decls : constant List_Id := Declarations (N);
579 Stats : constant Node_Id := Handled_Statement_Sequence (N);
580 Formals : constant Node_Id := Entry_Body_Formal_Part (N);
581 P_Type : constant Entity_Id := Current_Scope;
583 Entry_Name : Entity_Id;
586 Tasking_Used := True;
588 -- Entry_Name is initialized to Any_Id. It should get reset to the
589 -- matching entry entity. An error is signalled if it is not reset
591 Entry_Name := Any_Id;
595 if Present (Entry_Index_Specification (Formals)) then
596 Set_Ekind (Id, E_Entry_Family);
598 Set_Ekind (Id, E_Entry);
601 Set_Scope (Id, Current_Scope);
602 Set_Etype (Id, Standard_Void_Type);
603 Set_Accept_Address (Id, New_Elmt_List);
605 E := First_Entity (P_Type);
606 while Present (E) loop
607 if Chars (E) = Chars (Id)
608 and then (Ekind (E) = Ekind (Id))
609 and then Type_Conformant (Id, E)
612 Set_Convention (Id, Convention (E));
613 Set_Corresponding_Body (Parent (Entry_Name), Id);
614 Check_Fully_Conformant (Id, E, N);
616 if Ekind (Id) = E_Entry_Family then
617 if not Fully_Conformant_Discrete_Subtypes (
618 Discrete_Subtype_Definition (Parent (E)),
619 Discrete_Subtype_Definition
620 (Entry_Index_Specification (Formals)))
623 ("index not fully conformant with previous declaration",
624 Discrete_Subtype_Definition
625 (Entry_Index_Specification (Formals)));
628 -- The elaboration of the entry body does not recompute the
629 -- bounds of the index, which may have side effects. Inherit
630 -- the bounds from the entry declaration. This is critical
631 -- if the entry has a per-object constraint. If a bound is
632 -- given by a discriminant, it must be reanalyzed in order
633 -- to capture the discriminal of the current entry, rather
634 -- than that of the protected type.
637 Index_Spec : constant Node_Id :=
638 Entry_Index_Specification (Formals);
640 Def : constant Node_Id :=
642 (Discrete_Subtype_Definition (Parent (E)));
647 (Discrete_Subtype_Definition (Index_Spec))) = N_Range
649 Set_Etype (Def, Empty);
650 Set_Analyzed (Def, False);
652 -- Keep the original subtree to ensure a properly
653 -- formed tree (e.g. for ASIS use).
656 (Discrete_Subtype_Definition (Index_Spec), Def);
658 Set_Analyzed (Low_Bound (Def), False);
659 Set_Analyzed (High_Bound (Def), False);
661 if Denotes_Discriminant (Low_Bound (Def)) then
662 Set_Entity (Low_Bound (Def), Empty);
665 if Denotes_Discriminant (High_Bound (Def)) then
666 Set_Entity (High_Bound (Def), Empty);
670 Make_Index (Def, Index_Spec);
672 (Defining_Identifier (Index_Spec), Etype (Def));
684 if Entry_Name = Any_Id then
685 Error_Msg_N ("no entry declaration matches entry body", N);
688 elsif Has_Completion (Entry_Name) then
689 Error_Msg_N ("duplicate entry body", N);
693 Set_Has_Completion (Entry_Name);
694 Generate_Reference (Entry_Name, Id, 'b', Set_Ref => False);
695 Style.Check_Identifier (Id, Entry_Name);
698 Exp_Ch9.Expand_Entry_Barrier (N, Entry_Name);
699 Push_Scope (Entry_Name);
701 Install_Declarations (Entry_Name);
702 Set_Actual_Subtypes (N, Current_Scope);
704 -- The entity for the protected subprogram corresponding to the entry
705 -- has been created. We retain the name of this entity in the entry
706 -- body, for use when the corresponding subprogram body is created.
707 -- Note that entry bodies have no corresponding_spec, and there is no
708 -- easy link back in the tree between the entry body and the entity for
709 -- the entry itself, which is why we must propagate some attributes
710 -- explicitly from spec to body.
712 Set_Protected_Body_Subprogram
713 (Id, Protected_Body_Subprogram (Entry_Name));
715 Set_Entry_Parameters_Type
716 (Id, Entry_Parameters_Type (Entry_Name));
718 -- Add a declaration for the Protection object, renaming declarations
719 -- for the discriminals and privals and finally a declaration for the
720 -- entry family index (if applicable).
723 and then Is_Protected_Type (P_Type)
725 Install_Private_Data_Declarations
726 (Sloc (N), Entry_Name, P_Type, N, Decls);
729 if Present (Decls) then
730 Analyze_Declarations (Decls);
731 Inspect_Deferred_Constant_Completion (Decls);
734 if Present (Stats) then
738 -- Check for unreferenced variables etc. Before the Check_References
739 -- call, we transfer Never_Set_In_Source and Referenced flags from
740 -- parameters in the spec to the corresponding entities in the body,
741 -- since we want the warnings on the body entities. Note that we do
742 -- not have to transfer Referenced_As_LHS, since that flag can only
743 -- be set for simple variables.
745 -- At the same time, we set the flags on the spec entities to suppress
746 -- any warnings on the spec formals, since we also scan the spec.
747 -- Finally, we propagate the Entry_Component attribute to the body
748 -- formals, for use in the renaming declarations created later for the
749 -- formals (see exp_ch9.Add_Formal_Renamings).
756 E1 := First_Entity (Entry_Name);
757 while Present (E1) loop
758 E2 := First_Entity (Id);
759 while Present (E2) loop
760 exit when Chars (E1) = Chars (E2);
764 -- If no matching body entity, then we already had a detected
765 -- error of some kind, so just don't worry about these warnings.
771 if Ekind (E1) = E_Out_Parameter then
772 Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1));
773 Set_Never_Set_In_Source (E1, False);
776 Set_Referenced (E2, Referenced (E1));
778 Set_Entry_Component (E2, Entry_Component (E1));
784 Check_References (Id);
787 -- We still need to check references for the spec, since objects
788 -- declared in the body are chained (in the First_Entity sense) to
789 -- the spec rather than the body in the case of entries.
791 Check_References (Entry_Name);
793 -- Process the end label, and terminate the scope
795 Process_End_Label (Handled_Statement_Sequence (N), 't', Entry_Name);
798 -- If this is an entry family, remove the loop created to provide
799 -- a scope for the entry index.
801 if Ekind (Id) = E_Entry_Family
802 and then Present (Entry_Index_Specification (Formals))
806 end Analyze_Entry_Body;
808 ------------------------------------
809 -- Analyze_Entry_Body_Formal_Part --
810 ------------------------------------
812 procedure Analyze_Entry_Body_Formal_Part (N : Node_Id) is
813 Id : constant Entity_Id := Defining_Identifier (Parent (N));
814 Index : constant Node_Id := Entry_Index_Specification (N);
815 Formals : constant List_Id := Parameter_Specifications (N);
818 Tasking_Used := True;
820 if Present (Index) then
823 -- The entry index functions like a loop variable, thus it is known
824 -- to have a valid value.
826 Set_Is_Known_Valid (Defining_Identifier (Index));
829 if Present (Formals) then
830 Set_Scope (Id, Current_Scope);
832 Process_Formals (Formals, Parent (N));
835 end Analyze_Entry_Body_Formal_Part;
837 ------------------------------------
838 -- Analyze_Entry_Call_Alternative --
839 ------------------------------------
841 procedure Analyze_Entry_Call_Alternative (N : Node_Id) is
842 Call : constant Node_Id := Entry_Call_Statement (N);
845 Tasking_Used := True;
847 if Present (Pragmas_Before (N)) then
848 Analyze_List (Pragmas_Before (N));
851 if Nkind (Call) = N_Attribute_Reference then
853 -- Possibly a stream attribute, but definitely illegal. Other
854 -- illegalities, such as procedure calls, are diagnosed after
857 Error_Msg_N ("entry call alternative requires an entry call", Call);
863 if Is_Non_Empty_List (Statements (N)) then
864 Analyze_Statements (Statements (N));
866 end Analyze_Entry_Call_Alternative;
868 -------------------------------
869 -- Analyze_Entry_Declaration --
870 -------------------------------
872 procedure Analyze_Entry_Declaration (N : Node_Id) is
873 D_Sdef : constant Node_Id := Discrete_Subtype_Definition (N);
874 Def_Id : constant Entity_Id := Defining_Identifier (N);
875 Formals : constant List_Id := Parameter_Specifications (N);
878 Generate_Definition (Def_Id);
879 Tasking_Used := True;
882 Set_Ekind (Def_Id, E_Entry);
885 Set_Ekind (Def_Id, E_Entry_Family);
887 Make_Index (D_Sdef, N, Def_Id);
890 Set_Etype (Def_Id, Standard_Void_Type);
891 Set_Convention (Def_Id, Convention_Entry);
892 Set_Accept_Address (Def_Id, New_Elmt_List);
894 if Present (Formals) then
895 Set_Scope (Def_Id, Current_Scope);
897 Process_Formals (Formals, N);
898 Create_Extra_Formals (Def_Id);
902 if Ekind (Def_Id) = E_Entry then
903 New_Overloaded_Entity (Def_Id);
906 Generate_Reference_To_Formals (Def_Id);
907 end Analyze_Entry_Declaration;
909 ---------------------------------------
910 -- Analyze_Entry_Index_Specification --
911 ---------------------------------------
913 -- The Defining_Identifier of the entry index specification is local to the
914 -- entry body, but it must be available in the entry barrier which is
915 -- evaluated outside of the entry body. The index is eventually renamed as
916 -- a run-time object, so is visibility is strictly a front-end concern. In
917 -- order to make it available to the barrier, we create an additional
918 -- scope, as for a loop, whose only declaration is the index name. This
919 -- loop is not attached to the tree and does not appear as an entity local
920 -- to the protected type, so its existence need only be known to routines
921 -- that process entry families.
923 procedure Analyze_Entry_Index_Specification (N : Node_Id) is
924 Iden : constant Node_Id := Defining_Identifier (N);
925 Def : constant Node_Id := Discrete_Subtype_Definition (N);
926 Loop_Id : constant Entity_Id := Make_Temporary (Sloc (N), 'L');
929 Tasking_Used := True;
932 -- There is no elaboration of the entry index specification. Therefore,
933 -- if the index is a range, it is not resolved and expanded, but the
934 -- bounds are inherited from the entry declaration, and reanalyzed.
935 -- See Analyze_Entry_Body.
937 if Nkind (Def) /= N_Range then
941 Set_Ekind (Loop_Id, E_Loop);
942 Set_Scope (Loop_Id, Current_Scope);
943 Push_Scope (Loop_Id);
945 Set_Ekind (Iden, E_Entry_Index_Parameter);
946 Set_Etype (Iden, Etype (Def));
947 end Analyze_Entry_Index_Specification;
949 ----------------------------
950 -- Analyze_Protected_Body --
951 ----------------------------
953 procedure Analyze_Protected_Body (N : Node_Id) is
954 Body_Id : constant Entity_Id := Defining_Identifier (N);
958 -- This is initially the entity of the protected object or protected
959 -- type involved, but is replaced by the protected type always in the
960 -- case of a single protected declaration, since this is the proper
964 -- This is the entity of the protected object or protected type
965 -- involved, and is the entity used for cross-reference purposes (it
966 -- differs from Spec_Id in the case of a single protected object, since
967 -- Spec_Id is set to the protected type in this case).
970 Tasking_Used := True;
971 Set_Ekind (Body_Id, E_Protected_Body);
972 Spec_Id := Find_Concurrent_Spec (Body_Id);
975 and then Ekind (Spec_Id) = E_Protected_Type
979 elsif Present (Spec_Id)
980 and then Ekind (Etype (Spec_Id)) = E_Protected_Type
981 and then not Comes_From_Source (Etype (Spec_Id))
986 Error_Msg_N ("missing specification for protected body", Body_Id);
991 Generate_Reference (Ref_Id, Body_Id, 'b', Set_Ref => False);
992 Style.Check_Identifier (Body_Id, Spec_Id);
994 -- The declarations are always attached to the type
996 if Ekind (Spec_Id) /= E_Protected_Type then
997 Spec_Id := Etype (Spec_Id);
1000 Push_Scope (Spec_Id);
1001 Set_Corresponding_Spec (N, Spec_Id);
1002 Set_Corresponding_Body (Parent (Spec_Id), Body_Id);
1003 Set_Has_Completion (Spec_Id);
1004 Install_Declarations (Spec_Id);
1006 Expand_Protected_Body_Declarations (N, Spec_Id);
1008 Last_E := Last_Entity (Spec_Id);
1010 Analyze_Declarations (Declarations (N));
1012 -- For visibility purposes, all entities in the body are private. Set
1013 -- First_Private_Entity accordingly, if there was no private part in the
1014 -- protected declaration.
1016 if No (First_Private_Entity (Spec_Id)) then
1017 if Present (Last_E) then
1018 Set_First_Private_Entity (Spec_Id, Next_Entity (Last_E));
1020 Set_First_Private_Entity (Spec_Id, First_Entity (Spec_Id));
1024 Check_Completion (Body_Id);
1025 Check_References (Spec_Id);
1026 Process_End_Label (N, 't', Ref_Id);
1028 end Analyze_Protected_Body;
1030 ----------------------------------
1031 -- Analyze_Protected_Definition --
1032 ----------------------------------
1034 procedure Analyze_Protected_Definition (N : Node_Id) is
1038 procedure Undelay_Itypes (T : Entity_Id);
1039 -- Itypes created for the private components of a protected type
1040 -- do not receive freeze nodes, because there is no scope in which
1041 -- they can be elaborated, and they can depend on discriminants of
1042 -- the enclosed protected type. Given that the components can be
1043 -- composite types with inner components, we traverse recursively
1044 -- the private components of the protected type, and indicate that
1045 -- all itypes within are frozen. This ensures that no freeze nodes
1046 -- will be generated for them.
1048 -- On the other hand, components of the corresponding record are
1049 -- frozen (or receive itype references) as for other records.
1051 --------------------
1052 -- Undelay_Itypes --
1053 --------------------
1055 procedure Undelay_Itypes (T : Entity_Id) is
1059 if Is_Protected_Type (T) then
1060 Comp := First_Private_Entity (T);
1061 elsif Is_Record_Type (T) then
1062 Comp := First_Entity (T);
1067 while Present (Comp) loop
1069 and then Is_Itype (Comp)
1071 Set_Has_Delayed_Freeze (Comp, False);
1072 Set_Is_Frozen (Comp);
1074 if Is_Record_Type (Comp)
1075 or else Is_Protected_Type (Comp)
1077 Undelay_Itypes (Comp);
1085 -- Start of processing for Analyze_Protected_Definition
1088 Tasking_Used := True;
1089 Analyze_Declarations (Visible_Declarations (N));
1091 if Present (Private_Declarations (N))
1092 and then not Is_Empty_List (Private_Declarations (N))
1094 L := Last_Entity (Current_Scope);
1095 Analyze_Declarations (Private_Declarations (N));
1098 Set_First_Private_Entity (Current_Scope, Next_Entity (L));
1100 Set_First_Private_Entity (Current_Scope,
1101 First_Entity (Current_Scope));
1105 E := First_Entity (Current_Scope);
1106 while Present (E) loop
1107 if Ekind_In (E, E_Function, E_Procedure) then
1108 Set_Convention (E, Convention_Protected);
1110 elsif Is_Task_Type (Etype (E))
1111 or else Has_Task (Etype (E))
1113 Set_Has_Task (Current_Scope);
1119 Undelay_Itypes (Current_Scope);
1121 Check_Max_Entries (N, Max_Protected_Entries);
1122 Process_End_Label (N, 'e', Current_Scope);
1123 end Analyze_Protected_Definition;
1125 ----------------------------
1126 -- Analyze_Protected_Type --
1127 ----------------------------
1129 procedure Analyze_Protected_Type (N : Node_Id) is
1130 Def_Id : constant Entity_Id := Defining_Identifier (N);
1135 if No_Run_Time_Mode then
1136 Error_Msg_CRT ("protected type", N);
1140 Tasking_Used := True;
1141 Check_Restriction (No_Protected_Types, N);
1143 T := Find_Type_Name (N);
1145 -- In the case of an incomplete type, use the full view, unless it's not
1146 -- present (as can occur for an incomplete view from a limited with).
1148 if Ekind (T) = E_Incomplete_Type and then Present (Full_View (T)) then
1150 Set_Completion_Referenced (T);
1153 Set_Ekind (T, E_Protected_Type);
1154 Set_Is_First_Subtype (T, True);
1155 Init_Size_Align (T);
1157 Set_Has_Delayed_Freeze (T, True);
1158 Set_Stored_Constraint (T, No_Elist);
1161 if Ada_Version >= Ada_05 then
1162 Check_Interfaces (N, T);
1165 if Present (Discriminant_Specifications (N)) then
1166 if Has_Discriminants (T) then
1168 -- Install discriminants. Also, verify conformance of
1169 -- discriminants of previous and current view. ???
1171 Install_Declarations (T);
1173 Process_Discriminants (N);
1177 Set_Is_Constrained (T, not Has_Discriminants (T));
1179 Analyze (Protected_Definition (N));
1181 -- In the case where the protected type is declared at a nested level
1182 -- and the No_Local_Protected_Objects restriction applies, issue a
1183 -- warning that objects of the type will violate the restriction.
1185 if not Is_Library_Level_Entity (T)
1186 and then Comes_From_Source (T)
1187 and then Restrictions.Set (No_Local_Protected_Objects)
1189 Error_Msg_Sloc := Restrictions_Loc (No_Local_Protected_Objects);
1191 if Error_Msg_Sloc = No_Location then
1193 ("objects of this type will violate " &
1194 "`No_Local_Protected_Objects`?", N);
1197 ("objects of this type will violate " &
1198 "`No_Local_Protected_Objects`?#", N);
1202 -- Protected types with entries are controlled (because of the
1203 -- Protection component if nothing else), same for any protected type
1204 -- with interrupt handlers. Note that we need to analyze the protected
1205 -- definition to set Has_Entries and such.
1207 if (Abort_Allowed or else Restriction_Active (No_Entry_Queue) = False
1208 or else Number_Entries (T) > 1)
1211 or else Has_Interrupt_Handler (T)
1212 or else Has_Attach_Handler (T))
1214 Set_Has_Controlled_Component (T, True);
1217 -- The Ekind of components is E_Void during analysis to detect illegal
1218 -- uses. Now it can be set correctly.
1220 E := First_Entity (Current_Scope);
1221 while Present (E) loop
1222 if Ekind (E) = E_Void then
1223 Set_Ekind (E, E_Component);
1224 Init_Component_Location (E);
1232 -- Case of a completion of a private declaration
1235 and then Is_Private_Type (Def_Id)
1237 -- Deal with preelaborable initialization. Note that this processing
1238 -- is done by Process_Full_View, but as can be seen below, in this
1239 -- case the call to Process_Full_View is skipped if any serious
1240 -- errors have occurred, and we don't want to lose this check.
1242 if Known_To_Have_Preelab_Init (Def_Id) then
1243 Set_Must_Have_Preelab_Init (T);
1246 -- Create corresponding record now, because some private dependents
1247 -- may be subtypes of the partial view. Skip if errors are present,
1248 -- to prevent cascaded messages.
1250 if Serious_Errors_Detected = 0
1251 and then Expander_Active
1253 Expand_N_Protected_Type_Declaration (N);
1254 Process_Full_View (N, T, Def_Id);
1257 end Analyze_Protected_Type;
1259 ---------------------
1260 -- Analyze_Requeue --
1261 ---------------------
1263 procedure Analyze_Requeue (N : Node_Id) is
1264 Count : Natural := 0;
1265 Entry_Name : Node_Id := Name (N);
1266 Entry_Id : Entity_Id;
1268 Is_Disp_Req : Boolean;
1270 Enclosing : Entity_Id;
1271 Target_Obj : Node_Id := Empty;
1272 Req_Scope : Entity_Id;
1273 Outer_Ent : Entity_Id;
1276 Check_Restriction (No_Requeue_Statements, N);
1277 Check_Unreachable_Code (N);
1278 Tasking_Used := True;
1281 for J in reverse 0 .. Scope_Stack.Last loop
1282 Enclosing := Scope_Stack.Table (J).Entity;
1283 exit when Is_Entry (Enclosing);
1285 if not Ekind_In (Enclosing, E_Block, E_Loop) then
1286 Error_Msg_N ("requeue must appear within accept or entry body", N);
1291 Analyze (Entry_Name);
1293 if Etype (Entry_Name) = Any_Type then
1297 if Nkind (Entry_Name) = N_Selected_Component then
1298 Target_Obj := Prefix (Entry_Name);
1299 Entry_Name := Selector_Name (Entry_Name);
1302 -- If an explicit target object is given then we have to check the
1303 -- restrictions of 9.5.4(6).
1305 if Present (Target_Obj) then
1307 -- Locate containing concurrent unit and determine enclosing entry
1308 -- body or outermost enclosing accept statement within the unit.
1311 for S in reverse 0 .. Scope_Stack.Last loop
1312 Req_Scope := Scope_Stack.Table (S).Entity;
1314 exit when Ekind (Req_Scope) in Task_Kind
1315 or else Ekind (Req_Scope) in Protected_Kind;
1317 if Is_Entry (Req_Scope) then
1318 Outer_Ent := Req_Scope;
1322 pragma Assert (Present (Outer_Ent));
1324 -- Check that the accessibility level of the target object is not
1325 -- greater or equal to the outermost enclosing accept statement (or
1326 -- entry body) unless it is a parameter of the innermost enclosing
1327 -- accept statement (or entry body).
1329 if Object_Access_Level (Target_Obj) >= Scope_Depth (Outer_Ent)
1331 (not Is_Entity_Name (Target_Obj)
1332 or else Ekind (Entity (Target_Obj)) not in Formal_Kind
1333 or else Enclosing /= Scope (Entity (Target_Obj)))
1336 ("target object has invalid level for requeue", Target_Obj);
1340 -- Overloaded case, find right interpretation
1342 if Is_Overloaded (Entry_Name) then
1345 -- Loop over candidate interpretations and filter out any that are
1346 -- not parameterless, are not type conformant, are not entries, or
1347 -- do not come from source.
1349 Get_First_Interp (Entry_Name, I, It);
1350 while Present (It.Nam) loop
1352 -- Note: we test type conformance here, not subtype conformance.
1353 -- Subtype conformance will be tested later on, but it is better
1354 -- for error output in some cases not to do that here.
1356 if (No (First_Formal (It.Nam))
1357 or else (Type_Conformant (Enclosing, It.Nam)))
1358 and then Ekind (It.Nam) = E_Entry
1360 -- Ada 2005 (AI-345): Since protected and task types have
1361 -- primitive entry wrappers, we only consider source entries.
1363 if Comes_From_Source (It.Nam) then
1371 Get_Next_Interp (I, It);
1375 Error_Msg_N ("no entry matches context", N);
1378 elsif Count > 1 then
1379 Error_Msg_N ("ambiguous entry name in requeue", N);
1383 Set_Is_Overloaded (Entry_Name, False);
1384 Set_Entity (Entry_Name, Entry_Id);
1387 -- Non-overloaded cases
1389 -- For the case of a reference to an element of an entry family, the
1390 -- Entry_Name is an indexed component.
1392 elsif Nkind (Entry_Name) = N_Indexed_Component then
1394 -- Requeue to an entry out of the body
1396 if Nkind (Prefix (Entry_Name)) = N_Selected_Component then
1397 Entry_Id := Entity (Selector_Name (Prefix (Entry_Name)));
1399 -- Requeue from within the body itself
1401 elsif Nkind (Prefix (Entry_Name)) = N_Identifier then
1402 Entry_Id := Entity (Prefix (Entry_Name));
1405 Error_Msg_N ("invalid entry_name specified", N);
1409 -- If we had a requeue of the form REQUEUE A (B), then the parser
1410 -- accepted it (because it could have been a requeue on an entry index.
1411 -- If A turns out not to be an entry family, then the analysis of A (B)
1412 -- turned it into a function call.
1414 elsif Nkind (Entry_Name) = N_Function_Call then
1416 ("arguments not allowed in requeue statement",
1417 First (Parameter_Associations (Entry_Name)));
1420 -- Normal case of no entry family, no argument
1423 Entry_Id := Entity (Entry_Name);
1426 -- Ada 2005 (AI05-0030): Potential dispatching requeue statement. The
1427 -- target type must be a concurrent interface class-wide type and the
1428 -- entry name must be a procedure, flagged by pragma Implemented_By_
1432 Ada_Version >= Ada_05
1433 and then Present (Target_Obj)
1434 and then Is_Class_Wide_Type (Etype (Target_Obj))
1435 and then Is_Concurrent_Interface (Etype (Target_Obj))
1436 and then Ekind (Entry_Id) = E_Procedure
1437 and then Implemented_By_Entry (Entry_Id);
1439 -- Resolve entry, and check that it is subtype conformant with the
1440 -- enclosing construct if this construct has formals (RM 9.5.4(5)).
1441 -- Ada 2005 (AI05-0030): Do not emit an error for this specific case.
1443 if not Is_Entry (Entry_Id)
1444 and then not Is_Disp_Req
1446 Error_Msg_N ("expect entry name in requeue statement", Name (N));
1448 elsif Ekind (Entry_Id) = E_Entry_Family
1449 and then Nkind (Entry_Name) /= N_Indexed_Component
1451 Error_Msg_N ("missing index for entry family component", Name (N));
1454 Resolve_Entry (Name (N));
1455 Generate_Reference (Entry_Id, Entry_Name);
1457 if Present (First_Formal (Entry_Id)) then
1458 if VM_Target = JVM_Target then
1460 ("arguments unsupported in requeue statement",
1461 First_Formal (Entry_Id));
1465 -- Ada 2005 (AI05-0030): Perform type conformance after skipping
1466 -- the first parameter of Entry_Id since it is the interface
1467 -- controlling formal.
1471 Enclosing_Formal : Entity_Id;
1472 Target_Formal : Entity_Id;
1475 Enclosing_Formal := First_Formal (Enclosing);
1476 Target_Formal := Next_Formal (First_Formal (Entry_Id));
1477 while Present (Enclosing_Formal)
1478 and then Present (Target_Formal)
1480 if not Conforming_Types
1481 (T1 => Etype (Enclosing_Formal),
1482 T2 => Etype (Target_Formal),
1483 Ctype => Subtype_Conformant)
1485 Error_Msg_Node_2 := Target_Formal;
1487 ("formal & is not subtype conformant with &" &
1488 "in dispatching requeue", N, Enclosing_Formal);
1491 Next_Formal (Enclosing_Formal);
1492 Next_Formal (Target_Formal);
1496 Check_Subtype_Conformant (Enclosing, Entry_Id, Name (N));
1499 -- Processing for parameters accessed by the requeue
1505 Ent := First_Formal (Enclosing);
1506 while Present (Ent) loop
1508 -- For OUT or IN OUT parameter, the effect of the requeue is
1509 -- to assign the parameter a value on exit from the requeued
1510 -- body, so we can set it as source assigned. We also clear
1511 -- the Is_True_Constant indication. We do not need to clear
1512 -- Current_Value, since the effect of the requeue is to
1513 -- perform an unconditional goto so that any further
1514 -- references will not occur anyway.
1516 if Ekind_In (Ent, E_Out_Parameter, E_In_Out_Parameter) then
1517 Set_Never_Set_In_Source (Ent, False);
1518 Set_Is_True_Constant (Ent, False);
1521 -- For all parameters, the requeue acts as a reference,
1522 -- since the value of the parameter is passed to the new
1523 -- entry, so we want to suppress unreferenced warnings.
1525 Set_Referenced (Ent);
1531 end Analyze_Requeue;
1533 ------------------------------
1534 -- Analyze_Selective_Accept --
1535 ------------------------------
1537 procedure Analyze_Selective_Accept (N : Node_Id) is
1538 Alts : constant List_Id := Select_Alternatives (N);
1541 Accept_Present : Boolean := False;
1542 Terminate_Present : Boolean := False;
1543 Delay_Present : Boolean := False;
1544 Relative_Present : Boolean := False;
1545 Alt_Count : Uint := Uint_0;
1548 Check_Restriction (No_Select_Statements, N);
1549 Tasking_Used := True;
1551 -- Loop to analyze alternatives
1553 Alt := First (Alts);
1554 while Present (Alt) loop
1555 Alt_Count := Alt_Count + 1;
1558 if Nkind (Alt) = N_Delay_Alternative then
1559 if Delay_Present then
1561 if Relative_Present /=
1562 (Nkind (Delay_Statement (Alt)) = N_Delay_Relative_Statement)
1565 ("delay_until and delay_relative alternatives ", Alt);
1567 ("\cannot appear in the same selective_wait", Alt);
1571 Delay_Present := True;
1573 Nkind (Delay_Statement (Alt)) = N_Delay_Relative_Statement;
1576 elsif Nkind (Alt) = N_Terminate_Alternative then
1577 if Terminate_Present then
1578 Error_Msg_N ("only one terminate alternative allowed", N);
1580 Terminate_Present := True;
1581 Check_Restriction (No_Terminate_Alternatives, N);
1584 elsif Nkind (Alt) = N_Accept_Alternative then
1585 Accept_Present := True;
1587 -- Check for duplicate accept
1591 Stm : constant Node_Id := Accept_Statement (Alt);
1592 EDN : constant Node_Id := Entry_Direct_Name (Stm);
1596 if Nkind (EDN) = N_Identifier
1597 and then No (Condition (Alt))
1598 and then Present (Entity (EDN)) -- defend against junk
1599 and then Ekind (Entity (EDN)) = E_Entry
1601 Ent := Entity (EDN);
1603 Alt1 := First (Alts);
1604 while Alt1 /= Alt loop
1605 if Nkind (Alt1) = N_Accept_Alternative
1606 and then No (Condition (Alt1))
1609 Stm1 : constant Node_Id := Accept_Statement (Alt1);
1610 EDN1 : constant Node_Id := Entry_Direct_Name (Stm1);
1613 if Nkind (EDN1) = N_Identifier then
1614 if Entity (EDN1) = Ent then
1615 Error_Msg_Sloc := Sloc (Stm1);
1617 ("?accept duplicates one on line#", Stm);
1633 Check_Restriction (Max_Select_Alternatives, N, Alt_Count);
1634 Check_Potentially_Blocking_Operation (N);
1636 if Terminate_Present and Delay_Present then
1637 Error_Msg_N ("at most one of terminate or delay alternative", N);
1639 elsif not Accept_Present then
1641 ("select must contain at least one accept alternative", N);
1644 if Present (Else_Statements (N)) then
1645 if Terminate_Present or Delay_Present then
1646 Error_Msg_N ("else part not allowed with other alternatives", N);
1649 Analyze_Statements (Else_Statements (N));
1651 end Analyze_Selective_Accept;
1653 ------------------------------
1654 -- Analyze_Single_Protected --
1655 ------------------------------
1657 procedure Analyze_Single_Protected (N : Node_Id) is
1658 Loc : constant Source_Ptr := Sloc (N);
1659 Id : constant Node_Id := Defining_Identifier (N);
1663 O_Name : constant Entity_Id := Id;
1666 Generate_Definition (Id);
1667 Tasking_Used := True;
1669 -- The node is rewritten as a protected type declaration, in exact
1670 -- analogy with what is done with single tasks.
1673 Make_Defining_Identifier (Sloc (Id),
1674 New_External_Name (Chars (Id), 'T'));
1677 Make_Protected_Type_Declaration (Loc,
1678 Defining_Identifier => T,
1679 Protected_Definition => Relocate_Node (Protected_Definition (N)),
1680 Interface_List => Interface_List (N));
1683 Make_Object_Declaration (Loc,
1684 Defining_Identifier => O_Name,
1685 Object_Definition => Make_Identifier (Loc, Chars (T)));
1687 Rewrite (N, T_Decl);
1688 Insert_After (N, O_Decl);
1689 Mark_Rewrite_Insertion (O_Decl);
1691 -- Enter names of type and object before analysis, because the name of
1692 -- the object may be used in its own body.
1695 Set_Ekind (T, E_Protected_Type);
1698 Enter_Name (O_Name);
1699 Set_Ekind (O_Name, E_Variable);
1700 Set_Etype (O_Name, T);
1702 -- Instead of calling Analyze on the new node, call the proper analysis
1703 -- procedure directly. Otherwise the node would be expanded twice, with
1704 -- disastrous result.
1706 Analyze_Protected_Type (N);
1707 end Analyze_Single_Protected;
1709 -------------------------
1710 -- Analyze_Single_Task --
1711 -------------------------
1713 procedure Analyze_Single_Task (N : Node_Id) is
1714 Loc : constant Source_Ptr := Sloc (N);
1715 Id : constant Node_Id := Defining_Identifier (N);
1719 O_Name : constant Entity_Id := Id;
1722 Generate_Definition (Id);
1723 Tasking_Used := True;
1725 -- The node is rewritten as a task type declaration, followed by an
1726 -- object declaration of that anonymous task type.
1729 Make_Defining_Identifier (Sloc (Id),
1730 New_External_Name (Chars (Id), Suffix => "TK"));
1733 Make_Task_Type_Declaration (Loc,
1734 Defining_Identifier => T,
1735 Task_Definition => Relocate_Node (Task_Definition (N)),
1736 Interface_List => Interface_List (N));
1738 -- We use the original defining identifier of the single task in the
1739 -- generated object declaration, so that debugging information can
1740 -- be attached to it when compiling with -gnatD. The parent of the
1741 -- entity is the new object declaration. The single_task_declaration
1742 -- is not used further in semantics or code generation, but is scanned
1743 -- when generating debug information, and therefore needs the updated
1744 -- Sloc information for the entity (see Sprint).
1747 Make_Object_Declaration (Loc,
1748 Defining_Identifier => O_Name,
1749 Object_Definition => Make_Identifier (Loc, Chars (T)));
1751 Rewrite (N, T_Decl);
1752 Insert_After (N, O_Decl);
1753 Mark_Rewrite_Insertion (O_Decl);
1755 -- Enter names of type and object before analysis, because the name of
1756 -- the object may be used in its own body.
1759 Set_Ekind (T, E_Task_Type);
1762 Enter_Name (O_Name);
1763 Set_Ekind (O_Name, E_Variable);
1764 Set_Etype (O_Name, T);
1766 -- Instead of calling Analyze on the new node, call the proper analysis
1767 -- procedure directly. Otherwise the node would be expanded twice, with
1768 -- disastrous result.
1770 Analyze_Task_Type (N);
1771 end Analyze_Single_Task;
1773 -----------------------
1774 -- Analyze_Task_Body --
1775 -----------------------
1777 procedure Analyze_Task_Body (N : Node_Id) is
1778 Body_Id : constant Entity_Id := Defining_Identifier (N);
1779 Decls : constant List_Id := Declarations (N);
1780 HSS : constant Node_Id := Handled_Statement_Sequence (N);
1783 Spec_Id : Entity_Id;
1784 -- This is initially the entity of the task or task type involved, but
1785 -- is replaced by the task type always in the case of a single task
1786 -- declaration, since this is the proper scope to be used.
1789 -- This is the entity of the task or task type, and is the entity used
1790 -- for cross-reference purposes (it differs from Spec_Id in the case of
1791 -- a single task, since Spec_Id is set to the task type)
1794 Tasking_Used := True;
1795 Set_Ekind (Body_Id, E_Task_Body);
1796 Set_Scope (Body_Id, Current_Scope);
1797 Spec_Id := Find_Concurrent_Spec (Body_Id);
1799 -- The spec is either a task type declaration, or a single task
1800 -- declaration for which we have created an anonymous type.
1802 if Present (Spec_Id)
1803 and then Ekind (Spec_Id) = E_Task_Type
1807 elsif Present (Spec_Id)
1808 and then Ekind (Etype (Spec_Id)) = E_Task_Type
1809 and then not Comes_From_Source (Etype (Spec_Id))
1814 Error_Msg_N ("missing specification for task body", Body_Id);
1818 if Has_Completion (Spec_Id)
1819 and then Present (Corresponding_Body (Parent (Spec_Id)))
1821 if Nkind (Parent (Spec_Id)) = N_Task_Type_Declaration then
1822 Error_Msg_NE ("duplicate body for task type&", N, Spec_Id);
1825 Error_Msg_NE ("duplicate body for task&", N, Spec_Id);
1830 Generate_Reference (Ref_Id, Body_Id, 'b', Set_Ref => False);
1831 Style.Check_Identifier (Body_Id, Spec_Id);
1833 -- Deal with case of body of single task (anonymous type was created)
1835 if Ekind (Spec_Id) = E_Variable then
1836 Spec_Id := Etype (Spec_Id);
1839 Push_Scope (Spec_Id);
1840 Set_Corresponding_Spec (N, Spec_Id);
1841 Set_Corresponding_Body (Parent (Spec_Id), Body_Id);
1842 Set_Has_Completion (Spec_Id);
1843 Install_Declarations (Spec_Id);
1844 Last_E := Last_Entity (Spec_Id);
1846 Analyze_Declarations (Decls);
1847 Inspect_Deferred_Constant_Completion (Decls);
1849 -- For visibility purposes, all entities in the body are private. Set
1850 -- First_Private_Entity accordingly, if there was no private part in the
1851 -- protected declaration.
1853 if No (First_Private_Entity (Spec_Id)) then
1854 if Present (Last_E) then
1855 Set_First_Private_Entity (Spec_Id, Next_Entity (Last_E));
1857 Set_First_Private_Entity (Spec_Id, First_Entity (Spec_Id));
1861 -- Mark all handlers as not suitable for local raise optimization,
1862 -- since this optimization causes difficulties in a task context.
1864 if Present (Exception_Handlers (HSS)) then
1868 Handlr := First (Exception_Handlers (HSS));
1869 while Present (Handlr) loop
1870 Set_Local_Raise_Not_OK (Handlr);
1876 -- Now go ahead and complete analysis of the task body
1879 Check_Completion (Body_Id);
1880 Check_References (Body_Id);
1881 Check_References (Spec_Id);
1883 -- Check for entries with no corresponding accept
1889 Ent := First_Entity (Spec_Id);
1890 while Present (Ent) loop
1892 and then not Entry_Accepted (Ent)
1893 and then Comes_From_Source (Ent)
1895 Error_Msg_NE ("no accept for entry &?", N, Ent);
1902 Process_End_Label (HSS, 't', Ref_Id);
1904 end Analyze_Task_Body;
1906 -----------------------------
1907 -- Analyze_Task_Definition --
1908 -----------------------------
1910 procedure Analyze_Task_Definition (N : Node_Id) is
1914 Tasking_Used := True;
1916 if Present (Visible_Declarations (N)) then
1917 Analyze_Declarations (Visible_Declarations (N));
1920 if Present (Private_Declarations (N)) then
1921 L := Last_Entity (Current_Scope);
1922 Analyze_Declarations (Private_Declarations (N));
1925 Set_First_Private_Entity
1926 (Current_Scope, Next_Entity (L));
1928 Set_First_Private_Entity
1929 (Current_Scope, First_Entity (Current_Scope));
1933 Check_Max_Entries (N, Max_Task_Entries);
1934 Process_End_Label (N, 'e', Current_Scope);
1935 end Analyze_Task_Definition;
1937 -----------------------
1938 -- Analyze_Task_Type --
1939 -----------------------
1941 procedure Analyze_Task_Type (N : Node_Id) is
1942 Def_Id : constant Entity_Id := Defining_Identifier (N);
1946 Check_Restriction (No_Tasking, N);
1947 Tasking_Used := True;
1948 T := Find_Type_Name (N);
1949 Generate_Definition (T);
1951 -- In the case of an incomplete type, use the full view, unless it's not
1952 -- present (as can occur for an incomplete view from a limited with).
1954 if Ekind (T) = E_Incomplete_Type and then Present (Full_View (T)) then
1956 Set_Completion_Referenced (T);
1959 Set_Ekind (T, E_Task_Type);
1960 Set_Is_First_Subtype (T, True);
1961 Set_Has_Task (T, True);
1962 Init_Size_Align (T);
1964 Set_Has_Delayed_Freeze (T, True);
1965 Set_Stored_Constraint (T, No_Elist);
1968 if Ada_Version >= Ada_05 then
1969 Check_Interfaces (N, T);
1972 if Present (Discriminant_Specifications (N)) then
1973 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
1974 Error_Msg_N ("(Ada 83) task discriminant not allowed!", N);
1977 if Has_Discriminants (T) then
1979 -- Install discriminants. Also, verify conformance of
1980 -- discriminants of previous and current view. ???
1982 Install_Declarations (T);
1984 Process_Discriminants (N);
1988 Set_Is_Constrained (T, not Has_Discriminants (T));
1990 if Present (Task_Definition (N)) then
1991 Analyze_Task_Definition (Task_Definition (N));
1994 -- In the case where the task type is declared at a nested level and the
1995 -- No_Task_Hierarchy restriction applies, issue a warning that objects
1996 -- of the type will violate the restriction.
1998 if not Is_Library_Level_Entity (T)
1999 and then Comes_From_Source (T)
2000 and then Restrictions.Set (No_Task_Hierarchy)
2002 Error_Msg_Sloc := Restrictions_Loc (No_Task_Hierarchy);
2004 if Error_Msg_Sloc = No_Location then
2006 ("objects of this type will violate `No_Task_Hierarchy`?", N);
2009 ("objects of this type will violate `No_Task_Hierarchy`?#", N);
2015 -- Case of a completion of a private declaration
2018 and then Is_Private_Type (Def_Id)
2020 -- Deal with preelaborable initialization. Note that this processing
2021 -- is done by Process_Full_View, but as can be seen below, in this
2022 -- case the call to Process_Full_View is skipped if any serious
2023 -- errors have occurred, and we don't want to lose this check.
2025 if Known_To_Have_Preelab_Init (Def_Id) then
2026 Set_Must_Have_Preelab_Init (T);
2029 -- Create corresponding record now, because some private dependents
2030 -- may be subtypes of the partial view. Skip if errors are present,
2031 -- to prevent cascaded messages.
2033 if Serious_Errors_Detected = 0
2034 and then Expander_Active
2036 Expand_N_Task_Type_Declaration (N);
2037 Process_Full_View (N, T, Def_Id);
2040 end Analyze_Task_Type;
2042 -----------------------------------
2043 -- Analyze_Terminate_Alternative --
2044 -----------------------------------
2046 procedure Analyze_Terminate_Alternative (N : Node_Id) is
2048 Tasking_Used := True;
2050 if Present (Pragmas_Before (N)) then
2051 Analyze_List (Pragmas_Before (N));
2054 if Present (Condition (N)) then
2055 Analyze_And_Resolve (Condition (N), Any_Boolean);
2057 end Analyze_Terminate_Alternative;
2059 ------------------------------
2060 -- Analyze_Timed_Entry_Call --
2061 ------------------------------
2063 procedure Analyze_Timed_Entry_Call (N : Node_Id) is
2064 Trigger : constant Node_Id :=
2065 Entry_Call_Statement (Entry_Call_Alternative (N));
2066 Is_Disp_Select : Boolean := False;
2069 Check_Restriction (No_Select_Statements, N);
2070 Tasking_Used := True;
2072 -- Ada 2005 (AI-345): The trigger may be a dispatching call
2074 if Ada_Version >= Ada_05 then
2076 Check_Triggering_Statement (Trigger, N, Is_Disp_Select);
2079 -- Postpone the analysis of the statements till expansion. Analyze only
2080 -- if the expander is disabled in order to catch any semantic errors.
2082 if Is_Disp_Select then
2083 if not Expander_Active then
2084 Analyze (Entry_Call_Alternative (N));
2085 Analyze (Delay_Alternative (N));
2088 -- Regular select analysis
2091 Analyze (Entry_Call_Alternative (N));
2092 Analyze (Delay_Alternative (N));
2094 end Analyze_Timed_Entry_Call;
2096 ------------------------------------
2097 -- Analyze_Triggering_Alternative --
2098 ------------------------------------
2100 procedure Analyze_Triggering_Alternative (N : Node_Id) is
2101 Trigger : constant Node_Id := Triggering_Statement (N);
2104 Tasking_Used := True;
2106 if Present (Pragmas_Before (N)) then
2107 Analyze_List (Pragmas_Before (N));
2112 if Comes_From_Source (Trigger)
2113 and then Nkind (Trigger) not in N_Delay_Statement
2114 and then Nkind (Trigger) /= N_Entry_Call_Statement
2116 if Ada_Version < Ada_05 then
2118 ("triggering statement must be delay or entry call", Trigger);
2120 -- Ada 2005 (AI-345): If a procedure_call_statement is used for a
2121 -- procedure_or_entry_call, the procedure_name or procedure_prefix
2122 -- of the procedure_call_statement shall denote an entry renamed by a
2123 -- procedure, or (a view of) a primitive subprogram of a limited
2124 -- interface whose first parameter is a controlling parameter.
2126 elsif Nkind (Trigger) = N_Procedure_Call_Statement
2127 and then not Is_Renamed_Entry (Entity (Name (Trigger)))
2128 and then not Is_Controlling_Limited_Procedure
2129 (Entity (Name (Trigger)))
2131 Error_Msg_N ("triggering statement must be delay, procedure " &
2132 "or entry call", Trigger);
2136 if Is_Non_Empty_List (Statements (N)) then
2137 Analyze_Statements (Statements (N));
2139 end Analyze_Triggering_Alternative;
2141 -----------------------
2142 -- Check_Max_Entries --
2143 -----------------------
2145 procedure Check_Max_Entries (D : Node_Id; R : All_Parameter_Restrictions) is
2148 procedure Count (L : List_Id);
2149 -- Count entries in given declaration list
2155 procedure Count (L : List_Id) is
2164 while Present (D) loop
2165 if Nkind (D) = N_Entry_Declaration then
2167 DSD : constant Node_Id :=
2168 Discrete_Subtype_Definition (D);
2171 -- If not an entry family, then just one entry
2174 Ecount := Ecount + 1;
2176 -- If entry family with static bounds, count entries
2178 elsif Is_OK_Static_Subtype (Etype (DSD)) then
2180 Lo : constant Uint :=
2182 (Type_Low_Bound (Etype (DSD)));
2183 Hi : constant Uint :=
2185 (Type_High_Bound (Etype (DSD)));
2189 Ecount := Ecount + Hi - Lo + 1;
2193 -- Entry family with non-static bounds
2196 -- If restriction is set, then this is an error
2198 if Restrictions.Set (R) then
2200 ("static subtype required by Restriction pragma",
2203 -- Otherwise we record an unknown count restriction
2206 Check_Restriction (R, D);
2216 -- Start of processing for Check_Max_Entries
2220 Count (Visible_Declarations (D));
2221 Count (Private_Declarations (D));
2224 Check_Restriction (R, D, Ecount);
2226 end Check_Max_Entries;
2228 ----------------------
2229 -- Check_Interfaces --
2230 ----------------------
2232 procedure Check_Interfaces (N : Node_Id; T : Entity_Id) is
2234 Iface_Typ : Entity_Id;
2238 (Nkind_In (N, N_Protected_Type_Declaration, N_Task_Type_Declaration));
2240 if Present (Interface_List (N)) then
2241 Set_Is_Tagged_Type (T);
2243 Iface := First (Interface_List (N));
2244 while Present (Iface) loop
2245 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
2247 if not Is_Interface (Iface_Typ) then
2249 ("(Ada 2005) & must be an interface", Iface, Iface_Typ);
2252 -- Ada 2005 (AI-251): "The declaration of a specific descendant
2253 -- of an interface type freezes the interface type" RM 13.14.
2255 Freeze_Before (N, Etype (Iface));
2257 if Nkind (N) = N_Protected_Type_Declaration then
2259 -- Ada 2005 (AI-345): Protected types can only implement
2260 -- limited, synchronized, or protected interfaces (note that
2261 -- the predicate Is_Limited_Interface includes synchronized
2262 -- and protected interfaces).
2264 if Is_Task_Interface (Iface_Typ) then
2265 Error_Msg_N ("(Ada 2005) protected type cannot implement "
2266 & "a task interface", Iface);
2268 elsif not Is_Limited_Interface (Iface_Typ) then
2269 Error_Msg_N ("(Ada 2005) protected type cannot implement "
2270 & "a non-limited interface", Iface);
2273 else pragma Assert (Nkind (N) = N_Task_Type_Declaration);
2275 -- Ada 2005 (AI-345): Task types can only implement limited,
2276 -- synchronized, or task interfaces (note that the predicate
2277 -- Is_Limited_Interface includes synchronized and task
2280 if Is_Protected_Interface (Iface_Typ) then
2281 Error_Msg_N ("(Ada 2005) task type cannot implement a " &
2282 "protected interface", Iface);
2284 elsif not Is_Limited_Interface (Iface_Typ) then
2285 Error_Msg_N ("(Ada 2005) task type cannot implement a " &
2286 "non-limited interface", Iface);
2295 if not Has_Private_Declaration (T) then
2299 -- Additional checks on full-types associated with private type
2300 -- declarations. Search for the private type declaration.
2303 Full_T_Ifaces : Elist_Id;
2306 Priv_T_Ifaces : Elist_Id;
2309 Priv_T := First_Entity (Scope (T));
2311 pragma Assert (Present (Priv_T));
2313 if Is_Type (Priv_T) and then Present (Full_View (Priv_T)) then
2314 exit when Full_View (Priv_T) = T;
2317 Next_Entity (Priv_T);
2320 -- In case of synchronized types covering interfaces the private type
2321 -- declaration must be limited.
2323 if Present (Interface_List (N))
2324 and then not Is_Limited_Record (Priv_T)
2326 Error_Msg_Sloc := Sloc (Priv_T);
2327 Error_Msg_N ("(Ada 2005) limited type declaration expected for " &
2328 "private type#", T);
2331 -- RM 7.3 (7.1/2): If the full view has a partial view that is
2332 -- tagged then check RM 7.3 subsidiary rules.
2334 if Is_Tagged_Type (Priv_T)
2335 and then not Error_Posted (N)
2337 -- RM 7.3 (7.2/2): The partial view shall be a synchronized tagged
2338 -- type if and only if the full type is a synchronized tagged type
2340 if Is_Synchronized_Tagged_Type (Priv_T)
2341 and then not Is_Synchronized_Tagged_Type (T)
2344 ("(Ada 2005) full view must be a synchronized tagged " &
2345 "type (RM 7.3 (7.2/2))", Priv_T);
2347 elsif Is_Synchronized_Tagged_Type (T)
2348 and then not Is_Synchronized_Tagged_Type (Priv_T)
2351 ("(Ada 2005) partial view must be a synchronized tagged " &
2352 "type (RM 7.3 (7.2/2))", T);
2355 -- RM 7.3 (7.3/2): The partial view shall be a descendant of an
2356 -- interface type if and only if the full type is descendant of
2357 -- the interface type.
2359 if Present (Interface_List (N))
2360 or else (Is_Tagged_Type (Priv_T)
2361 and then Has_Interfaces
2362 (Priv_T, Use_Full_View => False))
2364 if Is_Tagged_Type (Priv_T) then
2366 (Priv_T, Priv_T_Ifaces, Use_Full_View => False);
2369 if Is_Tagged_Type (T) then
2370 Collect_Interfaces (T, Full_T_Ifaces);
2373 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
2375 if Present (Iface) then
2377 ("interface & not implemented by full type " &
2378 "(RM-2005 7.3 (7.3/2))", Priv_T, Iface);
2381 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
2383 if Present (Iface) then
2385 ("interface & not implemented by partial " &
2386 "view (RM-2005 7.3 (7.3/2))", T, Iface);
2391 end Check_Interfaces;
2393 --------------------------------
2394 -- Check_Triggering_Statement --
2395 --------------------------------
2397 procedure Check_Triggering_Statement
2399 Error_Node : Node_Id;
2400 Is_Dispatching : out Boolean)
2405 Is_Dispatching := False;
2407 -- It is not possible to have a dispatching trigger if we are not in
2410 if Ada_Version >= Ada_05
2411 and then Nkind (Trigger) = N_Procedure_Call_Statement
2412 and then Present (Parameter_Associations (Trigger))
2414 Param := First (Parameter_Associations (Trigger));
2416 if Is_Controlling_Actual (Param)
2417 and then Is_Interface (Etype (Param))
2419 if Is_Limited_Record (Etype (Param)) then
2420 Is_Dispatching := True;
2423 ("dispatching operation of limited or synchronized " &
2424 "interface required (RM 9.7.2(3))!", Error_Node);
2428 end Check_Triggering_Statement;
2430 --------------------------
2431 -- Find_Concurrent_Spec --
2432 --------------------------
2434 function Find_Concurrent_Spec (Body_Id : Entity_Id) return Entity_Id is
2435 Spec_Id : Entity_Id := Current_Entity_In_Scope (Body_Id);
2438 -- The type may have been given by an incomplete type declaration.
2439 -- Find full view now.
2441 if Present (Spec_Id) and then Ekind (Spec_Id) = E_Incomplete_Type then
2442 Spec_Id := Full_View (Spec_Id);
2446 end Find_Concurrent_Spec;
2448 --------------------------
2449 -- Install_Declarations --
2450 --------------------------
2452 procedure Install_Declarations (Spec : Entity_Id) is
2456 E := First_Entity (Spec);
2457 while Present (E) loop
2458 Prev := Current_Entity (E);
2459 Set_Current_Entity (E);
2460 Set_Is_Immediately_Visible (E);
2461 Set_Homonym (E, Prev);
2464 end Install_Declarations;