1------------------------------------------------------------------------------
2--                                                                          --
3--                         GNAT COMPILER COMPONENTS                         --
4--                                                                          --
5--                              P A R . C H 9                               --
6--                                                                          --
7--                                 B o d y                                  --
8--                                                                          --
9--          Copyright (C) 1992-2011, Free Software Foundation, Inc.         --
10--                                                                          --
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.          --
20--                                                                          --
21-- GNAT was originally developed  by the GNAT team at  New York University. --
22-- Extensive contributions were provided by Ada Core Technologies Inc.      --
23--                                                                          --
24------------------------------------------------------------------------------
25
26pragma Style_Checks (All_Checks);
27--  Turn off subprogram body ordering check. Subprograms are in order by RM
28--  section rather than alphabetical.
29
30separate (Par)
31package body Ch9 is
32
33   --  Local subprograms, used only in this chapter
34
35   function P_Accept_Alternative                   return Node_Id;
36   function P_Delay_Alternative                    return Node_Id;
37   function P_Delay_Relative_Statement             return Node_Id;
38   function P_Delay_Until_Statement                return Node_Id;
39   function P_Entry_Barrier                        return Node_Id;
40   function P_Entry_Body_Formal_Part               return Node_Id;
41   function P_Entry_Declaration                    return Node_Id;
42   function P_Entry_Index_Specification            return Node_Id;
43   function P_Protected_Definition                 return Node_Id;
44   function P_Protected_Operation_Declaration_Opt  return Node_Id;
45   function P_Protected_Operation_Items            return List_Id;
46   function P_Task_Items                           return List_Id;
47   function P_Task_Definition return Node_Id;
48
49   -----------------------------
50   -- 9.1  Task (also 10.1.3) --
51   -----------------------------
52
53   --  TASK_TYPE_DECLARATION ::=
54   --    task type DEFINING_IDENTIFIER [KNOWN_DISCRIMINANT_PART]
55   --      [ASPECT_SPECIFICATIONS]
56   --      [is [new INTERFACE_LIST with] TASK_DEFINITION];
57
58   --  SINGLE_TASK_DECLARATION ::=
59   --    task DEFINING_IDENTIFIER
60   --      [ASPECT_SPECIFICATIONS]
61   --      [is [new INTERFACE_LIST with] TASK_DEFINITION];
62
63   --  TASK_BODY ::=
64   --    task body DEFINING_IDENTIFIER is
65   --      DECLARATIVE_PART
66   --    begin
67   --      HANDLED_SEQUENCE_OF_STATEMENTS
68   --    end [task_IDENTIFIER]
69
70   --  TASK_BODY_STUB ::=
71   --    task body DEFINING_IDENTIFIER is separate;
72
73   --  This routine scans out a task declaration, task body, or task stub
74
75   --  The caller has checked that the initial token is TASK and scanned
76   --  past it, so that Token is set to the token after TASK
77
78   --  Error recovery: cannot raise Error_Resync
79
80   function P_Task return Node_Id is
81      Name_Node  : Node_Id;
82      Task_Node  : Node_Id;
83      Task_Sloc  : Source_Ptr;
84
85   begin
86      Push_Scope_Stack;
87      Scope.Table (Scope.Last).Etyp := E_Name;
88      Scope.Table (Scope.Last).Ecol := Start_Column;
89      Scope.Table (Scope.Last).Sloc := Token_Ptr;
90      Scope.Table (Scope.Last).Lreq := False;
91      Task_Sloc := Prev_Token_Ptr;
92
93      if Token = Tok_Body then
94         Scan; -- past BODY
95         Name_Node := P_Defining_Identifier (C_Is);
96         Scope.Table (Scope.Last).Labl := Name_Node;
97
98         if Token = Tok_Left_Paren then
99            Error_Msg_SC ("discriminant part not allowed in task body");
100            Discard_Junk_List (P_Known_Discriminant_Part_Opt);
101         end if;
102
103         TF_Is;
104
105         --  Task stub
106
107         if Token = Tok_Separate then
108            Scan; -- past SEPARATE
109            Task_Node := New_Node (N_Task_Body_Stub, Task_Sloc);
110            Set_Defining_Identifier (Task_Node, Name_Node);
111            TF_Semicolon;
112            Pop_Scope_Stack; -- remove unused entry
113
114         --  Task body
115
116         else
117            Task_Node := New_Node (N_Task_Body, Task_Sloc);
118            Set_Defining_Identifier (Task_Node, Name_Node);
119            Parse_Decls_Begin_End (Task_Node);
120         end if;
121
122         return Task_Node;
123
124      --  Otherwise we must have a task declaration
125
126      else
127         if Token = Tok_Type then
128            Scan; -- past TYPE
129            Task_Node := New_Node (N_Task_Type_Declaration, Task_Sloc);
130            Name_Node := P_Defining_Identifier;
131            Set_Defining_Identifier (Task_Node, Name_Node);
132            Scope.Table (Scope.Last).Labl := Name_Node;
133            Set_Discriminant_Specifications
134              (Task_Node, P_Known_Discriminant_Part_Opt);
135
136         else
137            Task_Node := New_Node (N_Single_Task_Declaration, Task_Sloc);
138            Name_Node := P_Defining_Identifier (C_Is);
139            Set_Defining_Identifier (Task_Node, Name_Node);
140            Scope.Table (Scope.Last).Labl := Name_Node;
141
142            if Token = Tok_Left_Paren then
143               Error_Msg_SC ("discriminant part not allowed for single task");
144               Discard_Junk_List (P_Known_Discriminant_Part_Opt);
145            end if;
146         end if;
147
148         --  Scan aspect specifications, don't eat the semicolon, since it
149         --  might not be there if we have an IS.
150
151         P_Aspect_Specifications (Task_Node, Semicolon => False);
152
153         --  Parse optional task definition. Note that P_Task_Definition scans
154         --  out the semicolon and possible aspect specifications as well as
155         --  the task definition itself.
156
157         if Token = Tok_Semicolon then
158
159            --  A little check, if the next token after semicolon is Entry,
160            --  then surely the semicolon should really be IS
161
162            Scan; -- past semicolon
163
164            if Token = Tok_Entry then
165               Error_Msg_SP -- CODEFIX
166                 ("|"";"" should be IS");
167               Set_Task_Definition (Task_Node, P_Task_Definition);
168            else
169               Pop_Scope_Stack; -- Remove unused entry
170            end if;
171
172         --  Here we have a task definition
173
174         else
175            TF_Is; -- must have IS if no semicolon
176
177            --  Ada 2005 (AI-345)
178
179            if Token = Tok_New then
180               Scan; --  past NEW
181
182               if Ada_Version < Ada_2005 then
183                  Error_Msg_SP ("task interface is an Ada 2005 extension");
184                  Error_Msg_SP ("\unit must be compiled with -gnat05 switch");
185               end if;
186
187               Set_Interface_List (Task_Node, New_List);
188
189               loop
190                  Append (P_Qualified_Simple_Name, Interface_List (Task_Node));
191                  exit when Token /= Tok_And;
192                  Scan; --  past AND
193               end loop;
194
195               if Token /= Tok_With then
196                  Error_Msg_SC -- CODEFIX
197                    ("WITH expected");
198               end if;
199
200               Scan; -- past WITH
201
202               if Token = Tok_Private then
203                  Error_Msg_SP -- CODEFIX
204                    ("PRIVATE not allowed in task type declaration");
205               end if;
206            end if;
207
208            Set_Task_Definition (Task_Node, P_Task_Definition);
209         end if;
210
211         return Task_Node;
212      end if;
213   end P_Task;
214
215   --------------------------------
216   -- 9.1  Task Type Declaration --
217   --------------------------------
218
219   --  Parsed by P_Task (9.1)
220
221   ----------------------------------
222   -- 9.1  Single Task Declaration --
223   ----------------------------------
224
225   --  Parsed by P_Task (9.1)
226
227   --------------------------
228   -- 9.1  Task Definition --
229   --------------------------
230
231   --  TASK_DEFINITION ::=
232   --      {TASK_ITEM}
233   --    [private
234   --      {TASK_ITEM}]
235   --    end [task_IDENTIFIER];
236
237   --  The caller has already made the scope stack entry
238
239   --  Note: there is a small deviation from official syntax here in that we
240   --  regard the semicolon after end as part of the Task_Definition, and in
241   --  the official syntax, it's part of the enclosing declaration. The reason
242   --  for this deviation is that otherwise the end processing would have to
243   --  be special cased, which would be a nuisance!
244
245   --  Error recovery:  cannot raise Error_Resync
246
247   function P_Task_Definition return Node_Id is
248      Def_Node  : Node_Id;
249
250   begin
251      Def_Node := New_Node (N_Task_Definition, Token_Ptr);
252      Set_Visible_Declarations (Def_Node, P_Task_Items);
253
254      if Token = Tok_Private then
255         Scan; -- past PRIVATE
256         Set_Private_Declarations (Def_Node, P_Task_Items);
257
258         --  Deal gracefully with multiple PRIVATE parts
259
260         while Token = Tok_Private loop
261            Error_Msg_SC ("only one private part allowed per task");
262            Scan; -- past PRIVATE
263            Append_List (P_Task_Items, Private_Declarations (Def_Node));
264         end loop;
265      end if;
266
267      End_Statements (Def_Node);
268      return Def_Node;
269   end P_Task_Definition;
270
271   --------------------
272   -- 9.1  Task Item --
273   --------------------
274
275   --  TASK_ITEM ::= ENTRY_DECLARATION | REPRESENTATION_CLAUSE
276
277   --  This subprogram scans a (possibly empty) list of task items and pragmas
278
279   --  Error recovery:  cannot raise Error_Resync
280
281   --  Note: a pragma can also be returned in this position
282
283   function P_Task_Items return List_Id is
284      Items      : List_Id;
285      Item_Node  : Node_Id;
286      Decl_Sloc  : Source_Ptr;
287
288   begin
289      --  Get rid of active SIS entry from outer scope. This means we will
290      --  miss some nested cases, but it doesn't seem worth the effort. See
291      --  discussion in Par for further details
292
293      SIS_Entry_Active := False;
294
295      --  Loop to scan out task items
296
297      Items := New_List;
298
299      Decl_Loop : loop
300         Decl_Sloc := Token_Ptr;
301
302         if Token = Tok_Pragma then
303            Append (P_Pragma, Items);
304
305         --  Ada 2005 (AI-397): Reserved words NOT and OVERRIDING
306         --  may begin an entry declaration.
307
308         elsif Token = Tok_Entry
309           or else Token = Tok_Not
310           or else Token = Tok_Overriding
311         then
312            Append (P_Entry_Declaration, Items);
313
314         elsif Token = Tok_For then
315            --  Representation clause in task declaration. The only rep
316            --  clause which is legal in a protected is an address clause,
317            --  so that is what we try to scan out.
318
319            Item_Node := P_Representation_Clause;
320
321            if Nkind (Item_Node) = N_At_Clause then
322               Append (Item_Node, Items);
323
324            elsif Nkind (Item_Node) = N_Attribute_Definition_Clause
325              and then Chars (Item_Node) = Name_Address
326            then
327               Append (Item_Node, Items);
328
329            else
330               Error_Msg
331                 ("the only representation clause " &
332                  "allowed here is an address clause!", Decl_Sloc);
333            end if;
334
335         elsif Token = Tok_Identifier
336           or else Token in Token_Class_Declk
337         then
338            Error_Msg_SC ("illegal declaration in task definition");
339            Resync_Past_Semicolon;
340
341         else
342            exit Decl_Loop;
343         end if;
344      end loop Decl_Loop;
345
346      return Items;
347   end P_Task_Items;
348
349   --------------------
350   -- 9.1  Task Body --
351   --------------------
352
353   --  Parsed by P_Task (9.1)
354
355   ----------------------------------
356   -- 9.4  Protected (also 10.1.3) --
357   ----------------------------------
358
359   --  PROTECTED_TYPE_DECLARATION ::=
360   --    protected type DEFINING_IDENTIFIER [KNOWN_DISCRIMINANT_PART]
361   --      [ASPECT_SPECIFICATIONS]
362   --    is [new INTERFACE_LIST with] PROTECTED_DEFINITION;
363
364   --  SINGLE_PROTECTED_DECLARATION ::=
365   --    protected DEFINING_IDENTIFIER
366   --      [ASPECT_SPECIFICATIONS]
367   --    is [new INTERFACE_LIST with] PROTECTED_DEFINITION;
368
369   --  PROTECTED_BODY ::=
370   --    protected body DEFINING_IDENTIFIER is
371   --      {PROTECTED_OPERATION_ITEM}
372   --    end [protected_IDENTIFIER];
373
374   --  PROTECTED_BODY_STUB ::=
375   --    protected body DEFINING_IDENTIFIER is separate;
376
377   --  This routine scans out a protected declaration, protected body
378   --  or a protected stub.
379
380   --  The caller has checked that the initial token is PROTECTED and
381   --  scanned past it, so Token is set to the following token.
382
383   --  Error recovery: cannot raise Error_Resync
384
385   function P_Protected return Node_Id is
386      Name_Node      : Node_Id;
387      Protected_Node : Node_Id;
388      Protected_Sloc : Source_Ptr;
389      Scan_State     : Saved_Scan_State;
390
391   begin
392      Push_Scope_Stack;
393      Scope.Table (Scope.Last).Etyp := E_Name;
394      Scope.Table (Scope.Last).Ecol := Start_Column;
395      Scope.Table (Scope.Last).Lreq := False;
396      Protected_Sloc := Prev_Token_Ptr;
397
398      if Token = Tok_Body then
399         Scan; -- past BODY
400         Name_Node := P_Defining_Identifier (C_Is);
401         Scope.Table (Scope.Last).Labl := Name_Node;
402
403         if Token = Tok_Left_Paren then
404            Error_Msg_SC ("discriminant part not allowed in protected body");
405            Discard_Junk_List (P_Known_Discriminant_Part_Opt);
406         end if;
407
408         TF_Is;
409
410         --  Protected stub
411
412         if Token = Tok_Separate then
413            Scan; -- past SEPARATE
414            Protected_Node := New_Node (N_Protected_Body_Stub, Protected_Sloc);
415            Set_Defining_Identifier (Protected_Node, Name_Node);
416            TF_Semicolon;
417            Pop_Scope_Stack; -- remove unused entry
418
419         --  Protected body
420
421         else
422            Protected_Node := New_Node (N_Protected_Body, Protected_Sloc);
423            Set_Defining_Identifier (Protected_Node, Name_Node);
424            Set_Declarations (Protected_Node, P_Protected_Operation_Items);
425            End_Statements (Protected_Node);
426         end if;
427
428         return Protected_Node;
429
430      --  Otherwise we must have a protected declaration
431
432      else
433         if Token = Tok_Type then
434            Scan; -- past TYPE
435            Protected_Node :=
436              New_Node (N_Protected_Type_Declaration, Protected_Sloc);
437            Name_Node := P_Defining_Identifier (C_Is);
438            Set_Defining_Identifier (Protected_Node, Name_Node);
439            Scope.Table (Scope.Last).Labl := Name_Node;
440            Set_Discriminant_Specifications
441              (Protected_Node, P_Known_Discriminant_Part_Opt);
442
443         else
444            Protected_Node :=
445              New_Node (N_Single_Protected_Declaration, Protected_Sloc);
446            Name_Node := P_Defining_Identifier (C_Is);
447            Set_Defining_Identifier (Protected_Node, Name_Node);
448
449            if Token = Tok_Left_Paren then
450               Error_Msg_SC
451                 ("discriminant part not allowed for single protected");
452               Discard_Junk_List (P_Known_Discriminant_Part_Opt);
453            end if;
454
455            Scope.Table (Scope.Last).Labl := Name_Node;
456         end if;
457
458         P_Aspect_Specifications (Protected_Node, Semicolon => False);
459
460         --  Check for semicolon not followed by IS, this is something like
461
462         --    protected type r;
463
464         --  where we want
465
466         --    protected type r IS END;
467
468         if Token = Tok_Semicolon then
469            Save_Scan_State (Scan_State); -- at semicolon
470            Scan; -- past semicolon
471
472            if Token /= Tok_Is then
473               Restore_Scan_State (Scan_State);
474               Error_Msg_SC -- CODEFIX
475                 ("missing IS");
476               Set_Protected_Definition (Protected_Node,
477                 Make_Protected_Definition (Token_Ptr,
478                   Visible_Declarations => Empty_List,
479                   End_Label           => Empty));
480
481               SIS_Entry_Active := False;
482               End_Statements
483                 (Protected_Definition (Protected_Node), Protected_Node);
484               return Protected_Node;
485            end if;
486
487            Error_Msg_SP -- CODEFIX
488              ("|extra ""("" ignored");
489         end if;
490
491         T_Is;
492
493         --  Ada 2005 (AI-345)
494
495         if Token = Tok_New then
496            Scan; --  past NEW
497
498            if Ada_Version < Ada_2005 then
499               Error_Msg_SP ("protected interface is an Ada 2005 extension");
500               Error_Msg_SP ("\unit must be compiled with -gnat05 switch");
501            end if;
502
503            Set_Interface_List (Protected_Node, New_List);
504
505            loop
506               Append (P_Qualified_Simple_Name,
507                 Interface_List (Protected_Node));
508
509               exit when Token /= Tok_And;
510               Scan; --  past AND
511            end loop;
512
513            if Token /= Tok_With then
514               Error_Msg_SC -- CODEFIX
515                 ("WITH expected");
516            end if;
517
518            Scan; -- past WITH
519         end if;
520
521         Set_Protected_Definition (Protected_Node, P_Protected_Definition);
522         return Protected_Node;
523      end if;
524   end P_Protected;
525
526   -------------------------------------
527   -- 9.4  Protected Type Declaration --
528   -------------------------------------
529
530   --  Parsed by P_Protected (9.4)
531
532   ---------------------------------------
533   -- 9.4  Single Protected Declaration --
534   ---------------------------------------
535
536   --  Parsed by P_Protected (9.4)
537
538   -------------------------------
539   -- 9.4  Protected Definition --
540   -------------------------------
541
542   --  PROTECTED_DEFINITION ::=
543   --      {PROTECTED_OPERATION_DECLARATION}
544   --    [private
545   --      {PROTECTED_ELEMENT_DECLARATION}]
546   --    end [protected_IDENTIFIER]
547
548   --  PROTECTED_ELEMENT_DECLARATION ::=
549   --    PROTECTED_OPERATION_DECLARATION
550   --  | COMPONENT_DECLARATION
551
552   --  The caller has already established the scope stack entry
553
554   --  Error recovery: cannot raise Error_Resync
555
556   function P_Protected_Definition return Node_Id is
557      Def_Node  : Node_Id;
558      Item_Node : Node_Id;
559
560   begin
561      Def_Node := New_Node (N_Protected_Definition, Token_Ptr);
562
563      --  Get rid of active SIS entry from outer scope. This means we will
564      --  miss some nested cases, but it doesn't seem worth the effort. See
565      --  discussion in Par for further details
566
567      SIS_Entry_Active := False;
568
569      --  Loop to scan visible declarations (protected operation declarations)
570
571      Set_Visible_Declarations (Def_Node, New_List);
572
573      loop
574         Item_Node := P_Protected_Operation_Declaration_Opt;
575         exit when No (Item_Node);
576         Append (Item_Node, Visible_Declarations (Def_Node));
577      end loop;
578
579      --  Deal with PRIVATE part (including graceful handling of multiple
580      --  PRIVATE parts).
581
582      Private_Loop : while Token = Tok_Private loop
583         if No (Private_Declarations (Def_Node)) then
584            Set_Private_Declarations (Def_Node, New_List);
585         else
586            Error_Msg_SC ("duplicate private part");
587         end if;
588
589         Scan; -- past PRIVATE
590
591         Declaration_Loop : loop
592            if Token = Tok_Identifier then
593               P_Component_Items (Private_Declarations (Def_Node));
594            else
595               Item_Node := P_Protected_Operation_Declaration_Opt;
596               exit Declaration_Loop when No (Item_Node);
597               Append (Item_Node, Private_Declarations (Def_Node));
598            end if;
599         end loop Declaration_Loop;
600      end loop Private_Loop;
601
602      End_Statements (Def_Node);
603      return Def_Node;
604   end P_Protected_Definition;
605
606   ------------------------------------------
607   -- 9.4  Protected Operation Declaration --
608   ------------------------------------------
609
610   --  PROTECTED_OPERATION_DECLARATION ::=
611   --    SUBPROGRAM_DECLARATION
612   --  | ENTRY_DECLARATION
613   --  | REPRESENTATION_CLAUSE
614
615   --  Error recovery: cannot raise Error_Resync
616
617   --  Note: a pragma can also be returned in this position
618
619   --  We are not currently permitting representation clauses to appear as
620   --  protected operation declarations, do we have to rethink this???
621
622   function P_Protected_Operation_Declaration_Opt return Node_Id is
623      L : List_Id;
624      P : Source_Ptr;
625
626      function P_Entry_Or_Subprogram_With_Indicator return Node_Id;
627      --  Ada 2005 (AI-397): Parse an entry or a subprogram with an overriding
628      --  indicator. The caller has checked that the initial token is NOT or
629      --  OVERRIDING.
630
631      ------------------------------------------
632      -- P_Entry_Or_Subprogram_With_Indicator --
633      ------------------------------------------
634
635      function P_Entry_Or_Subprogram_With_Indicator return Node_Id is
636         Decl           : Node_Id := Error;
637         Is_Overriding  : Boolean := False;
638         Not_Overriding : Boolean := False;
639
640      begin
641         if Token = Tok_Not then
642            Scan;  -- past NOT
643
644            if Token = Tok_Overriding then
645               Scan;  -- past OVERRIDING
646               Not_Overriding := True;
647            else
648               Error_Msg_SC -- CODEFIX
649                 ("OVERRIDING expected!");
650            end if;
651
652         else
653            Scan;  -- past OVERRIDING
654            Is_Overriding := True;
655         end if;
656
657         if Is_Overriding or else Not_Overriding then
658            if Ada_Version < Ada_2005 then
659               Error_Msg_SP ("overriding indicator is an Ada 2005 extension");
660               Error_Msg_SP ("\unit must be compiled with -gnat05 switch");
661
662            elsif Token = Tok_Entry then
663               Decl := P_Entry_Declaration;
664
665               Set_Must_Override     (Decl, Is_Overriding);
666               Set_Must_Not_Override (Decl, Not_Overriding);
667
668            elsif Token = Tok_Function or else Token = Tok_Procedure then
669               Decl := P_Subprogram (Pf_Decl_Pexp);
670
671               Set_Must_Override     (Specification (Decl), Is_Overriding);
672               Set_Must_Not_Override (Specification (Decl), Not_Overriding);
673
674            else
675               Error_Msg_SC -- CODEFIX
676                 ("ENTRY, FUNCTION or PROCEDURE expected!");
677            end if;
678         end if;
679
680         return Decl;
681      end P_Entry_Or_Subprogram_With_Indicator;
682
683   --  Start of processing for P_Protected_Operation_Declaration_Opt
684
685   begin
686      --  This loop runs more than once only when a junk declaration
687      --  is skipped.
688
689      loop
690         if Token = Tok_Pragma then
691            return P_Pragma;
692
693         elsif Token = Tok_Not or else Token = Tok_Overriding then
694            return P_Entry_Or_Subprogram_With_Indicator;
695
696         elsif Token = Tok_Entry then
697            return P_Entry_Declaration;
698
699         elsif Token = Tok_Function or else Token = Tok_Procedure then
700            return P_Subprogram (Pf_Decl_Pexp);
701
702         elsif Token = Tok_Identifier then
703            L := New_List;
704            P := Token_Ptr;
705            Skip_Declaration (L);
706
707            if Nkind (First (L)) = N_Object_Declaration then
708               Error_Msg
709                 ("component must be declared in private part of " &
710                  "protected type", P);
711            else
712               Error_Msg
713                 ("illegal declaration in protected definition", P);
714            end if;
715
716         elsif Token in Token_Class_Declk then
717            Error_Msg_SC ("illegal declaration in protected definition");
718            Resync_Past_Semicolon;
719
720            --  Return now to avoid cascaded messages if next declaration
721            --  is a valid component declaration.
722
723            return Error;
724
725         elsif Token = Tok_For then
726            Error_Msg_SC
727              ("representation clause not allowed in protected definition");
728            Resync_Past_Semicolon;
729
730         else
731            return Empty;
732         end if;
733      end loop;
734   end P_Protected_Operation_Declaration_Opt;
735
736   -----------------------------------
737   -- 9.4  Protected Operation Item --
738   -----------------------------------
739
740   --  PROTECTED_OPERATION_ITEM ::=
741   --    SUBPROGRAM_DECLARATION
742   --  | SUBPROGRAM_BODY
743   --  | ENTRY_BODY
744   --  | REPRESENTATION_CLAUSE
745
746   --  This procedure parses and returns a list of protected operation items
747
748   --  We are not currently permitting representation clauses to appear
749   --  as protected operation items, do we have to rethink this???
750
751   function P_Protected_Operation_Items return List_Id is
752      Item_List : List_Id;
753
754   begin
755      Item_List := New_List;
756
757      loop
758         if Token = Tok_Entry or else Bad_Spelling_Of (Tok_Entry) then
759            Append (P_Entry_Body, Item_List);
760
761         --  If the operation starts with procedure, function, or an overriding
762         --  indicator ("overriding" or "not overriding"), parse a subprogram.
763
764         elsif Token = Tok_Function or else Bad_Spelling_Of (Tok_Function)
765                 or else
766               Token = Tok_Procedure or else Bad_Spelling_Of (Tok_Procedure)
767                 or else
768               Token = Tok_Overriding or else Bad_Spelling_Of (Tok_Overriding)
769                 or else
770               Token = Tok_Not or else Bad_Spelling_Of (Tok_Not)
771         then
772            Append (P_Subprogram (Pf_Decl_Pbod_Pexp), Item_List);
773
774         elsif Token = Tok_Pragma or else Bad_Spelling_Of (Tok_Pragma) then
775            P_Pragmas_Opt (Item_List);
776
777         elsif Token = Tok_Private or else Bad_Spelling_Of (Tok_Private) then
778            Error_Msg_SC ("PRIVATE not allowed in protected body");
779            Scan; -- past PRIVATE
780
781         elsif Token = Tok_Identifier then
782            Error_Msg_SC ("all components must be declared in spec!");
783            Resync_Past_Semicolon;
784
785         elsif Token in Token_Class_Declk then
786            Error_Msg_SC ("this declaration not allowed in protected body");
787            Resync_Past_Semicolon;
788
789         else
790            exit;
791         end if;
792      end loop;
793
794      return Item_List;
795   end P_Protected_Operation_Items;
796
797   ------------------------------
798   -- 9.5.2  Entry Declaration --
799   ------------------------------
800
801   --  ENTRY_DECLARATION ::=
802   --    [OVERRIDING_INDICATOR]
803   --    entry DEFINING_IDENTIFIER [(DISCRETE_SUBTYPE_DEFINITION)]
804   --      PARAMETER_PROFILE;
805   --        [ASPECT_SPECIFICATIONS];
806
807   --  The caller has checked that the initial token is ENTRY, NOT or
808   --  OVERRIDING.
809
810   --  Error recovery: cannot raise Error_Resync
811
812   function P_Entry_Declaration return Node_Id is
813      Decl_Node  : Node_Id;
814      Scan_State : Saved_Scan_State;
815
816      --  Flags for optional overriding indication. Two flags are needed,
817      --  to distinguish positive and negative overriding indicators from
818      --  the absence of any indicator.
819
820      Is_Overriding  : Boolean := False;
821      Not_Overriding : Boolean := False;
822
823   begin
824      --  Ada 2005 (AI-397): Scan leading overriding indicator
825
826      if Token = Tok_Not then
827         Scan;  -- past NOT
828
829         if Token = Tok_Overriding then
830            Scan;  -- part OVERRIDING
831            Not_Overriding := True;
832         else
833            Error_Msg_SC -- CODEFIX
834              ("OVERRIDING expected!");
835         end if;
836
837      elsif Token = Tok_Overriding then
838         Scan;  -- part OVERRIDING
839         Is_Overriding := True;
840      end if;
841
842      if Is_Overriding or else Not_Overriding then
843         if Ada_Version < Ada_2005 then
844            Error_Msg_SP ("overriding indicator is an Ada 2005 extension");
845            Error_Msg_SP ("\unit must be compiled with -gnat05 switch");
846
847         elsif Token /= Tok_Entry then
848            Error_Msg_SC -- CODEFIX
849              ("ENTRY expected!");
850         end if;
851      end if;
852
853      Decl_Node := New_Node (N_Entry_Declaration, Token_Ptr);
854      Scan; -- past ENTRY
855
856      Set_Defining_Identifier
857        (Decl_Node, P_Defining_Identifier (C_Left_Paren_Semicolon));
858
859      --  If left paren, could be (Discrete_Subtype_Definition) or Formal_Part
860
861      if Token = Tok_Left_Paren then
862         Scan; -- past (
863
864         --  If identifier after left paren, could still be either
865
866         if Token = Tok_Identifier then
867            Save_Scan_State (Scan_State); -- at Id
868            Scan; -- past Id
869
870            --  If comma or colon after Id, must be Formal_Part
871
872            if Token = Tok_Comma or else Token = Tok_Colon then
873               Restore_Scan_State (Scan_State); -- to Id
874               Set_Parameter_Specifications (Decl_Node, P_Formal_Part);
875
876            --  Else if Id without comma or colon, must be discrete subtype
877            --  defn
878
879            else
880               Restore_Scan_State (Scan_State); -- to Id
881               Set_Discrete_Subtype_Definition
882                 (Decl_Node, P_Discrete_Subtype_Definition);
883               T_Right_Paren;
884               Set_Parameter_Specifications (Decl_Node, P_Parameter_Profile);
885            end if;
886
887         --  If no Id, must be discrete subtype definition
888
889         else
890            Set_Discrete_Subtype_Definition
891              (Decl_Node, P_Discrete_Subtype_Definition);
892            T_Right_Paren;
893            Set_Parameter_Specifications (Decl_Node, P_Parameter_Profile);
894         end if;
895      end if;
896
897      if Is_Overriding then
898         Set_Must_Override (Decl_Node);
899      elsif Not_Overriding then
900         Set_Must_Not_Override (Decl_Node);
901      end if;
902
903      --  Error recovery check for illegal return
904
905      if Token = Tok_Return then
906         Error_Msg_SC ("entry cannot have return value!");
907         Scan;
908         Discard_Junk_Node (P_Subtype_Indication);
909      end if;
910
911      --  Error recovery check for improper use of entry barrier in spec
912
913      if Token = Tok_When then
914         Error_Msg_SC ("barrier not allowed here (belongs in body)");
915         Scan; -- past WHEN;
916         Discard_Junk_Node (P_Expression_No_Right_Paren);
917      end if;
918
919      P_Aspect_Specifications (Decl_Node);
920      return Decl_Node;
921
922   exception
923      when Error_Resync =>
924         Resync_Past_Semicolon;
925         return Error;
926   end P_Entry_Declaration;
927
928   -----------------------------
929   -- 9.5.2  Accept Statement --
930   -----------------------------
931
932   --  ACCEPT_STATEMENT ::=
933   --    accept entry_DIRECT_NAME
934   --      [(ENTRY_INDEX)] PARAMETER_PROFILE [do
935   --        HANDLED_SEQUENCE_OF_STATEMENTS
936   --    end [entry_IDENTIFIER]];
937
938   --  The caller has checked that the initial token is ACCEPT
939
940   --  Error recovery: cannot raise Error_Resync. If an error occurs, the
941   --  scan is resynchronized past the next semicolon and control returns.
942
943   function P_Accept_Statement return Node_Id is
944      Scan_State  : Saved_Scan_State;
945      Accept_Node : Node_Id;
946      Hand_Seq    : Node_Id;
947
948   begin
949      Push_Scope_Stack;
950      Scope.Table (Scope.Last).Sloc := Token_Ptr;
951      Scope.Table (Scope.Last).Ecol := Start_Column;
952
953      Accept_Node := New_Node (N_Accept_Statement, Token_Ptr);
954      Scan; -- past ACCEPT
955      Scope.Table (Scope.Last).Labl := Token_Node;
956
957      Set_Entry_Direct_Name (Accept_Node, P_Identifier (C_Do));
958
959      --  Left paren could be (Entry_Index) or Formal_Part, determine which
960
961      if Token = Tok_Left_Paren then
962         Save_Scan_State (Scan_State); -- at left paren
963         Scan; -- past left paren
964
965         --  If first token after left paren not identifier, then Entry_Index
966
967         if Token /= Tok_Identifier then
968            Set_Entry_Index (Accept_Node, P_Expression);
969            T_Right_Paren;
970            Set_Parameter_Specifications (Accept_Node, P_Parameter_Profile);
971
972         --  First token after left paren is identifier, could be either case
973
974         else -- Token = Tok_Identifier
975            Scan; -- past identifier
976
977            --  If identifier followed by comma or colon, must be Formal_Part
978
979            if Token = Tok_Comma or else Token = Tok_Colon then
980               Restore_Scan_State (Scan_State); -- to left paren
981               Set_Parameter_Specifications (Accept_Node, P_Parameter_Profile);
982
983            --  If identifier not followed by comma/colon, must be entry index
984
985            else
986               Restore_Scan_State (Scan_State); -- to left paren
987               Scan; -- past left paren (again!)
988               Set_Entry_Index (Accept_Node, P_Expression);
989               T_Right_Paren;
990               Set_Parameter_Specifications (Accept_Node, P_Parameter_Profile);
991            end if;
992         end if;
993      end if;
994
995      --  Scan out DO if present
996
997      if Token = Tok_Do then
998         Scope.Table (Scope.Last).Etyp := E_Name;
999         Scope.Table (Scope.Last).Lreq := False;
1000         Scan; -- past DO
1001         Hand_Seq := P_Handled_Sequence_Of_Statements;
1002         Set_Handled_Statement_Sequence (Accept_Node, Hand_Seq);
1003         End_Statements (Handled_Statement_Sequence (Accept_Node));
1004
1005         --  Exception handlers not allowed in Ada 95 node
1006
1007         if Present (Exception_Handlers (Hand_Seq)) then
1008            if Ada_Version = Ada_83 then
1009               Error_Msg_N
1010                 ("(Ada 83) exception handlers in accept not allowed",
1011                  First_Non_Pragma (Exception_Handlers (Hand_Seq)));
1012            end if;
1013         end if;
1014
1015      else
1016         Pop_Scope_Stack; -- discard unused entry
1017         TF_Semicolon;
1018      end if;
1019
1020      return Accept_Node;
1021
1022   --  If error, resynchronize past semicolon
1023
1024   exception
1025      when Error_Resync =>
1026         Resync_Past_Semicolon;
1027         Pop_Scope_Stack; -- discard unused entry
1028         return Error;
1029
1030   end P_Accept_Statement;
1031
1032   ------------------------
1033   -- 9.5.2  Entry Index --
1034   ------------------------
1035
1036   --  Parsed by P_Expression (4.4)
1037
1038   -----------------------
1039   -- 9.5.2  Entry Body --
1040   -----------------------
1041
1042   --  ENTRY_BODY ::=
1043   --    entry DEFINING_IDENTIFIER ENTRY_BODY_FORMAL_PART ENTRY_BARRIER is
1044   --      DECLARATIVE_PART
1045   --    begin
1046   --      HANDLED_SEQUENCE_OF_STATEMENTS
1047   --    end [entry_IDENTIFIER];
1048
1049   --  The caller has checked that the initial token is ENTRY
1050
1051   --  Error_Recovery: cannot raise Error_Resync
1052
1053   function P_Entry_Body return Node_Id is
1054      Entry_Node       : Node_Id;
1055      Formal_Part_Node : Node_Id;
1056      Name_Node        : Node_Id;
1057
1058   begin
1059      Push_Scope_Stack;
1060      Entry_Node := New_Node (N_Entry_Body, Token_Ptr);
1061      Scan; -- past ENTRY
1062
1063      Scope.Table (Scope.Last).Ecol := Start_Column;
1064      Scope.Table (Scope.Last).Lreq := False;
1065      Scope.Table (Scope.Last).Etyp := E_Name;
1066      Scope.Table (Scope.Last).Sloc := Token_Ptr;
1067
1068      Name_Node := P_Defining_Identifier;
1069      Set_Defining_Identifier (Entry_Node, Name_Node);
1070      Scope.Table (Scope.Last).Labl := Name_Node;
1071
1072      Formal_Part_Node := P_Entry_Body_Formal_Part;
1073      Set_Entry_Body_Formal_Part (Entry_Node, Formal_Part_Node);
1074
1075      Set_Condition (Formal_Part_Node, P_Entry_Barrier);
1076      Parse_Decls_Begin_End (Entry_Node);
1077      return Entry_Node;
1078   end P_Entry_Body;
1079
1080   -----------------------------------
1081   -- 9.5.2  Entry Body Formal Part --
1082   -----------------------------------
1083
1084   --  ENTRY_BODY_FORMAL_PART ::=
1085   --    [(ENTRY_INDEX_SPECIFICATION)] [PARAMETER_PART]
1086
1087   --  Error_Recovery: cannot raise Error_Resync
1088
1089   function P_Entry_Body_Formal_Part return Node_Id is
1090      Fpart_Node : Node_Id;
1091      Scan_State : Saved_Scan_State;
1092
1093   begin
1094      Fpart_Node := New_Node (N_Entry_Body_Formal_Part, Token_Ptr);
1095
1096      --  See if entry index specification present, and if so parse it
1097
1098      if Token = Tok_Left_Paren then
1099         Save_Scan_State (Scan_State); -- at left paren
1100         Scan; -- past left paren
1101
1102         if Token = Tok_For then
1103            Set_Entry_Index_Specification
1104              (Fpart_Node, P_Entry_Index_Specification);
1105            T_Right_Paren;
1106         else
1107            Restore_Scan_State (Scan_State); -- to left paren
1108         end if;
1109
1110      --  Check for (common?) case of left paren omitted before FOR. This
1111      --  is a tricky case, because the corresponding missing left paren
1112      --  can cause real havoc if a formal part is present which gets
1113      --  treated as part of the discrete subtype definition of the
1114      --  entry index specification, so just give error and resynchronize
1115
1116      elsif Token = Tok_For then
1117         T_Left_Paren; -- to give error message
1118         Resync_To_When;
1119      end if;
1120
1121      Set_Parameter_Specifications (Fpart_Node, P_Parameter_Profile);
1122      return Fpart_Node;
1123   end P_Entry_Body_Formal_Part;
1124
1125   --------------------------
1126   -- 9.5.2  Entry Barrier --
1127   --------------------------
1128
1129   --  ENTRY_BARRIER ::= when CONDITION
1130
1131   --  Error_Recovery: cannot raise Error_Resync
1132
1133   function P_Entry_Barrier return Node_Id is
1134      Bnode : Node_Id;
1135
1136   begin
1137      if Token = Tok_When then
1138         Scan; -- past WHEN;
1139         Bnode := P_Expression_No_Right_Paren;
1140
1141         if Token = Tok_Colon_Equal then
1142            Error_Msg_SC -- CODEFIX
1143              ("|"":="" should be ""=""");
1144            Scan;
1145            Bnode := P_Expression_No_Right_Paren;
1146         end if;
1147
1148      else
1149         T_When; -- to give error message
1150         Bnode := Error;
1151      end if;
1152
1153      TF_Is;
1154      return Bnode;
1155   end P_Entry_Barrier;
1156
1157   --------------------------------------
1158   -- 9.5.2  Entry Index Specification --
1159   --------------------------------------
1160
1161   --  ENTRY_INDEX_SPECIFICATION ::=
1162   --    for DEFINING_IDENTIFIER in DISCRETE_SUBTYPE_DEFINITION
1163
1164   --  Error recovery: can raise Error_Resync
1165
1166   function P_Entry_Index_Specification return Node_Id is
1167      Iterator_Node : Node_Id;
1168
1169   begin
1170      Iterator_Node := New_Node (N_Entry_Index_Specification, Token_Ptr);
1171      T_For; -- past FOR
1172      Set_Defining_Identifier (Iterator_Node, P_Defining_Identifier (C_In));
1173      T_In;
1174      Set_Discrete_Subtype_Definition
1175        (Iterator_Node, P_Discrete_Subtype_Definition);
1176      return Iterator_Node;
1177   end P_Entry_Index_Specification;
1178
1179   ---------------------------------
1180   -- 9.5.3  Entry Call Statement --
1181   ---------------------------------
1182
1183   --  Parsed by P_Name (4.1). Within a select, an entry call is parsed
1184   --  by P_Select_Statement (9.7)
1185
1186   ------------------------------
1187   -- 9.5.4  Requeue Statement --
1188   ------------------------------
1189
1190   --  REQUEUE_STATEMENT ::= requeue entry_NAME [with abort];
1191
1192   --  The caller has checked that the initial token is requeue
1193
1194   --  Error recovery: can raise Error_Resync
1195
1196   function P_Requeue_Statement return Node_Id is
1197      Requeue_Node : Node_Id;
1198
1199   begin
1200      Requeue_Node := New_Node (N_Requeue_Statement, Token_Ptr);
1201      Scan; -- past REQUEUE
1202      Set_Name (Requeue_Node, P_Name);
1203
1204      if Token = Tok_With then
1205         Scan; -- past WITH
1206         T_Abort;
1207         Set_Abort_Present (Requeue_Node, True);
1208      end if;
1209
1210      TF_Semicolon;
1211      return Requeue_Node;
1212   end P_Requeue_Statement;
1213
1214   --------------------------
1215   -- 9.6  Delay Statement --
1216   --------------------------
1217
1218   --  DELAY_STATEMENT ::=
1219   --    DELAY_UNTIL_STATEMENT
1220   --  | DELAY_RELATIVE_STATEMENT
1221
1222   --  The caller has checked that the initial token is DELAY
1223
1224   --  Error recovery: cannot raise Error_Resync
1225
1226   function P_Delay_Statement return Node_Id is
1227   begin
1228      Scan; -- past DELAY
1229
1230      --  The following check for delay until misused in Ada 83 doesn't catch
1231      --  all cases, but it's good enough to catch most of them!
1232
1233      if Token_Name = Name_Until then
1234         Check_95_Keyword (Tok_Until, Tok_Left_Paren);
1235         Check_95_Keyword (Tok_Until, Tok_Identifier);
1236      end if;
1237
1238      if Token = Tok_Until then
1239         return P_Delay_Until_Statement;
1240      else
1241         return P_Delay_Relative_Statement;
1242      end if;
1243   end P_Delay_Statement;
1244
1245   --------------------------------
1246   -- 9.6  Delay Until Statement --
1247   --------------------------------
1248
1249   --  DELAY_UNTIL_STATEMENT ::= delay until delay_EXPRESSION;
1250
1251   --  The caller has checked that the initial token is DELAY, scanned it
1252   --  out and checked that the current token is UNTIL
1253
1254   --  Error recovery: cannot raise Error_Resync
1255
1256   function P_Delay_Until_Statement return Node_Id is
1257      Delay_Node : Node_Id;
1258
1259   begin
1260      Delay_Node := New_Node (N_Delay_Until_Statement, Prev_Token_Ptr);
1261      Scan; -- past UNTIL
1262      Set_Expression (Delay_Node, P_Expression_No_Right_Paren);
1263      TF_Semicolon;
1264      return Delay_Node;
1265   end P_Delay_Until_Statement;
1266
1267   -----------------------------------
1268   -- 9.6  Delay Relative Statement --
1269   -----------------------------------
1270
1271   --  DELAY_RELATIVE_STATEMENT ::= delay delay_EXPRESSION;
1272
1273   --  The caller has checked that the initial token is DELAY, scanned it
1274   --  out and determined that the current token is not UNTIL
1275
1276   --  Error recovery: cannot raise Error_Resync
1277
1278   function P_Delay_Relative_Statement return Node_Id is
1279      Delay_Node : Node_Id;
1280
1281   begin
1282      Delay_Node := New_Node (N_Delay_Relative_Statement, Prev_Token_Ptr);
1283      Set_Expression (Delay_Node, P_Expression_No_Right_Paren);
1284      Check_Simple_Expression_In_Ada_83 (Expression (Delay_Node));
1285      TF_Semicolon;
1286      return Delay_Node;
1287   end P_Delay_Relative_Statement;
1288
1289   ---------------------------
1290   -- 9.7  Select Statement --
1291   ---------------------------
1292
1293   --  SELECT_STATEMENT ::=
1294   --    SELECTIVE_ACCEPT
1295   --  | TIMED_ENTRY_CALL
1296   --  | CONDITIONAL_ENTRY_CALL
1297   --  | ASYNCHRONOUS_SELECT
1298
1299   --  SELECTIVE_ACCEPT ::=
1300   --    select
1301   --      [GUARD]
1302   --        SELECT_ALTERNATIVE
1303   --    {or
1304   --      [GUARD]
1305   --        SELECT_ALTERNATIVE
1306   --    [else
1307   --      SEQUENCE_OF_STATEMENTS]
1308   --    end select;
1309
1310   --  GUARD ::= when CONDITION =>
1311
1312   --  Note: the guard preceding a select alternative is included as part
1313   --  of the node generated for a selective accept alternative.
1314
1315   --  SELECT_ALTERNATIVE ::=
1316   --    ACCEPT_ALTERNATIVE
1317   --  | DELAY_ALTERNATIVE
1318   --  | TERMINATE_ALTERNATIVE
1319
1320   --  TIMED_ENTRY_CALL ::=
1321   --    select
1322   --      ENTRY_CALL_ALTERNATIVE
1323   --    or
1324   --      DELAY_ALTERNATIVE
1325   --    end select;
1326
1327   --  CONDITIONAL_ENTRY_CALL ::=
1328   --    select
1329   --      ENTRY_CALL_ALTERNATIVE
1330   --    else
1331   --      SEQUENCE_OF_STATEMENTS
1332   --    end select;
1333
1334   --  ENTRY_CALL_ALTERNATIVE ::=
1335   --    ENTRY_CALL_STATEMENT [SEQUENCE_OF_STATEMENTS]
1336
1337   --  ASYNCHRONOUS_SELECT ::=
1338   --    select
1339   --      TRIGGERING_ALTERNATIVE
1340   --    then abort
1341   --      ABORTABLE_PART
1342   --    end select;
1343
1344   --  TRIGGERING_ALTERNATIVE ::=
1345   --    TRIGGERING_STATEMENT [SEQUENCE_OF_STATEMENTS]
1346
1347   --  TRIGGERING_STATEMENT ::= ENTRY_CALL_STATEMENT | DELAY_STATEMENT
1348
1349   --  The caller has checked that the initial token is SELECT
1350
1351   --  Error recovery: can raise Error_Resync
1352
1353   function P_Select_Statement return Node_Id is
1354      Select_Node    : Node_Id;
1355      Select_Sloc    : Source_Ptr;
1356      Stmnt_Sloc     : Source_Ptr;
1357      Ecall_Node     : Node_Id;
1358      Alternative    : Node_Id;
1359      Select_Pragmas : List_Id;
1360      Alt_Pragmas    : List_Id;
1361      Statement_List : List_Id;
1362      Alt_List       : List_Id;
1363      Cond_Expr      : Node_Id;
1364      Delay_Stmnt    : Node_Id;
1365
1366   begin
1367      Push_Scope_Stack;
1368      Scope.Table (Scope.Last).Etyp := E_Select;
1369      Scope.Table (Scope.Last).Ecol := Start_Column;
1370      Scope.Table (Scope.Last).Sloc := Token_Ptr;
1371      Scope.Table (Scope.Last).Labl := Error;
1372
1373      Select_Sloc := Token_Ptr;
1374      Scan; -- past SELECT
1375      Stmnt_Sloc := Token_Ptr;
1376      Select_Pragmas := P_Pragmas_Opt;
1377
1378      --  If first token after select is designator, then we have an entry
1379      --  call, which must be the start of a conditional entry call, timed
1380      --  entry call or asynchronous select
1381
1382      if Token in Token_Class_Desig then
1383
1384         --  Scan entry call statement
1385
1386         begin
1387            Ecall_Node := P_Name;
1388
1389            --  ??  The following two clauses exactly parallel code in ch5
1390            --      and should be combined sometime
1391
1392            if Nkind (Ecall_Node) = N_Indexed_Component then
1393               declare
1394                  Prefix_Node : constant Node_Id := Prefix (Ecall_Node);
1395                  Exprs_Node  : constant List_Id := Expressions (Ecall_Node);
1396
1397               begin
1398                  Change_Node (Ecall_Node, N_Procedure_Call_Statement);
1399                  Set_Name (Ecall_Node, Prefix_Node);
1400                  Set_Parameter_Associations (Ecall_Node, Exprs_Node);
1401               end;
1402
1403            elsif Nkind (Ecall_Node) = N_Function_Call then
1404               declare
1405                  Fname_Node  : constant Node_Id := Name (Ecall_Node);
1406                  Params_List : constant List_Id :=
1407                                  Parameter_Associations (Ecall_Node);
1408
1409               begin
1410                  Change_Node (Ecall_Node, N_Procedure_Call_Statement);
1411                  Set_Name (Ecall_Node, Fname_Node);
1412                  Set_Parameter_Associations (Ecall_Node, Params_List);
1413               end;
1414
1415            elsif Nkind (Ecall_Node) = N_Identifier
1416              or else Nkind (Ecall_Node) = N_Selected_Component
1417            then
1418               --  Case of a call to a parameterless entry
1419
1420               declare
1421                  C_Node : constant Node_Id :=
1422                         New_Node (N_Procedure_Call_Statement, Stmnt_Sloc);
1423               begin
1424                  Set_Name (C_Node, Ecall_Node);
1425                  Set_Parameter_Associations (C_Node, No_List);
1426                  Ecall_Node := C_Node;
1427               end;
1428            end if;
1429
1430            TF_Semicolon;
1431
1432         exception
1433            when Error_Resync =>
1434               Resync_Past_Semicolon;
1435               return Error;
1436         end;
1437
1438         Statement_List := P_Sequence_Of_Statements (SS_Eltm_Ortm_Tatm);
1439
1440         --  OR follows, we have a timed entry call
1441
1442         if Token = Tok_Or then
1443            Scan; -- past OR
1444            Alt_Pragmas := P_Pragmas_Opt;
1445
1446            Select_Node := New_Node (N_Timed_Entry_Call, Select_Sloc);
1447            Set_Entry_Call_Alternative (Select_Node,
1448              Make_Entry_Call_Alternative (Stmnt_Sloc,
1449                Entry_Call_Statement => Ecall_Node,
1450                Pragmas_Before       => Select_Pragmas,
1451                Statements           => Statement_List));
1452
1453            --  Only possibility is delay alternative. If we have anything
1454            --  else, give message, and treat as conditional entry call.
1455
1456            if Token /= Tok_Delay then
1457               Error_Msg_SC
1458                 ("only allowed alternative in timed entry call is delay!");
1459               Discard_Junk_List (P_Sequence_Of_Statements (SS_Sreq));
1460               Set_Delay_Alternative (Select_Node, Error);
1461
1462            else
1463               Set_Delay_Alternative (Select_Node, P_Delay_Alternative);
1464               Set_Pragmas_Before
1465                 (Delay_Alternative (Select_Node), Alt_Pragmas);
1466            end if;
1467
1468         --  ELSE follows, we have a conditional entry call
1469
1470         elsif Token = Tok_Else then
1471            Scan; -- past ELSE
1472            Select_Node := New_Node (N_Conditional_Entry_Call, Select_Sloc);
1473
1474            Set_Entry_Call_Alternative (Select_Node,
1475              Make_Entry_Call_Alternative (Stmnt_Sloc,
1476                Entry_Call_Statement => Ecall_Node,
1477                Pragmas_Before       => Select_Pragmas,
1478                Statements           => Statement_List));
1479
1480            Set_Else_Statements
1481              (Select_Node, P_Sequence_Of_Statements (SS_Sreq));
1482
1483         --  Only remaining case is THEN ABORT (asynchronous select)
1484
1485         elsif Token = Tok_Abort then
1486            Select_Node :=
1487              Make_Asynchronous_Select (Select_Sloc,
1488                Triggering_Alternative =>
1489                  Make_Triggering_Alternative (Stmnt_Sloc,
1490                    Triggering_Statement => Ecall_Node,
1491                    Pragmas_Before       => Select_Pragmas,
1492                    Statements           => Statement_List),
1493                Abortable_Part => P_Abortable_Part);
1494
1495         --  Else error
1496
1497         else
1498            if Ada_Version = Ada_83 then
1499               Error_Msg_BC ("OR or ELSE expected");
1500            else
1501               Error_Msg_BC ("OR or ELSE or THEN ABORT expected");
1502            end if;
1503
1504            Select_Node := Error;
1505         end if;
1506
1507         End_Statements;
1508
1509      --  Here we have a selective accept or an asynchronous select (first
1510      --  token after SELECT is other than a designator token).
1511
1512      else
1513         --  If we have delay with no guard, could be asynchronous select
1514
1515         if Token = Tok_Delay then
1516            Delay_Stmnt := P_Delay_Statement;
1517            Statement_List := P_Sequence_Of_Statements (SS_Eltm_Ortm_Tatm);
1518
1519            --  Asynchronous select
1520
1521            if Token = Tok_Abort then
1522               Select_Node :=
1523                 Make_Asynchronous_Select (Select_Sloc,
1524                   Triggering_Alternative =>
1525                     Make_Triggering_Alternative (Stmnt_Sloc,
1526                       Triggering_Statement => Delay_Stmnt,
1527                       Pragmas_Before       => Select_Pragmas,
1528                       Statements           => Statement_List),
1529                     Abortable_Part => P_Abortable_Part);
1530
1531               End_Statements;
1532               return Select_Node;
1533
1534            --  Delay which was not an asynchronous select. Must be a selective
1535            --  accept, and since at least one accept statement is required,
1536            --  we must have at least one OR phrase present.
1537
1538            else
1539               Alt_List := New_List (
1540                 Make_Delay_Alternative (Stmnt_Sloc,
1541                   Delay_Statement => Delay_Stmnt,
1542                   Pragmas_Before  => Select_Pragmas,
1543                   Statements      => Statement_List));
1544               T_Or;
1545               Alt_Pragmas := P_Pragmas_Opt;
1546            end if;
1547
1548         --  If not a delay statement, then must be another possibility for
1549         --  a selective accept alternative, or perhaps a guard is present
1550
1551         else
1552            Alt_List := New_List;
1553            Alt_Pragmas := Select_Pragmas;
1554         end if;
1555
1556         Select_Node := New_Node (N_Selective_Accept, Select_Sloc);
1557         Set_Select_Alternatives (Select_Node, Alt_List);
1558
1559         --  Scan out selective accept alternatives. On entry to this loop,
1560         --  we are just past a SELECT or OR token, and any pragmas that
1561         --  immediately follow the SELECT or OR are in Alt_Pragmas.
1562
1563         loop
1564            if Token = Tok_When then
1565
1566               if Present (Alt_Pragmas) then
1567                  Error_Msg_SC ("pragmas may not precede guard");
1568               end if;
1569
1570               Scan; --  past WHEN
1571               Cond_Expr := P_Expression_No_Right_Paren;
1572               T_Arrow;
1573               Alt_Pragmas := P_Pragmas_Opt;
1574
1575            else
1576               Cond_Expr := Empty;
1577            end if;
1578
1579            if Token = Tok_Accept then
1580               Alternative := P_Accept_Alternative;
1581
1582               --  Check for junk attempt at asynchronous select using
1583               --  an Accept alternative as the triggering statement
1584
1585               if Token = Tok_Abort
1586                 and then Is_Empty_List (Alt_List)
1587                 and then No (Cond_Expr)
1588               then
1589                  Error_Msg
1590                    ("triggering statement must be entry call or delay",
1591                     Sloc (Alternative));
1592                  Scan; -- past junk ABORT
1593                  Discard_Junk_List (P_Sequence_Of_Statements (SS_Sreq));
1594                  End_Statements;
1595                  return Error;
1596               end if;
1597
1598            elsif Token = Tok_Delay then
1599               Alternative := P_Delay_Alternative;
1600
1601            elsif Token = Tok_Terminate then
1602               Alternative := P_Terminate_Alternative;
1603
1604            else
1605               Error_Msg_SC
1606                 ("select alternative (ACCEPT, ABORT, DELAY) expected");
1607               Alternative := Error;
1608
1609               if Token = Tok_Semicolon then
1610                  Scan; -- past junk semicolon
1611               end if;
1612            end if;
1613
1614            --  THEN ABORT at this stage is just junk
1615
1616            if Token = Tok_Abort then
1617               Error_Msg_SP ("misplaced `THEN ABORT`");
1618               Scan; -- past junk ABORT
1619               Discard_Junk_List (P_Sequence_Of_Statements (SS_Sreq));
1620               End_Statements;
1621               return Error;
1622
1623            else
1624               if Alternative /= Error then
1625                  Set_Condition (Alternative, Cond_Expr);
1626                  Set_Pragmas_Before (Alternative, Alt_Pragmas);
1627                  Append (Alternative, Alt_List);
1628               end if;
1629
1630               exit when Token /= Tok_Or;
1631            end if;
1632
1633            T_Or;
1634            Alt_Pragmas := P_Pragmas_Opt;
1635         end loop;
1636
1637         if Token = Tok_Else then
1638            Scan; -- past ELSE
1639            Set_Else_Statements
1640              (Select_Node, P_Sequence_Of_Statements (SS_Ortm_Sreq));
1641
1642            if Token = Tok_Or then
1643               Error_Msg_SC ("select alternative cannot follow else part!");
1644            end if;
1645         end if;
1646
1647         End_Statements;
1648      end if;
1649
1650      return Select_Node;
1651   end P_Select_Statement;
1652
1653   -----------------------------
1654   -- 9.7.1  Selective Accept --
1655   -----------------------------
1656
1657   --  Parsed by P_Select_Statement (9.7)
1658
1659   ------------------
1660   -- 9.7.1  Guard --
1661   ------------------
1662
1663   --  Parsed by P_Select_Statement (9.7)
1664
1665   -------------------------------
1666   -- 9.7.1  Select Alternative --
1667   -------------------------------
1668
1669   --  SELECT_ALTERNATIVE ::=
1670   --    ACCEPT_ALTERNATIVE
1671   --  | DELAY_ALTERNATIVE
1672   --  | TERMINATE_ALTERNATIVE
1673
1674   --  Note: the guard preceding a select alternative is included as part
1675   --  of the node generated for a selective accept alternative.
1676
1677   --  Error recovery: cannot raise Error_Resync
1678
1679   -------------------------------
1680   -- 9.7.1  Accept Alternative --
1681   -------------------------------
1682
1683   --  ACCEPT_ALTERNATIVE ::=
1684   --    ACCEPT_STATEMENT [SEQUENCE_OF_STATEMENTS]
1685
1686   --  Error_Recovery: Cannot raise Error_Resync
1687
1688   --  Note: the caller is responsible for setting the Pragmas_Before
1689   --  field of the returned N_Terminate_Alternative node.
1690
1691   function P_Accept_Alternative return Node_Id is
1692      Accept_Alt_Node : Node_Id;
1693
1694   begin
1695      Accept_Alt_Node := New_Node (N_Accept_Alternative, Token_Ptr);
1696      Set_Accept_Statement (Accept_Alt_Node, P_Accept_Statement);
1697
1698      --  Note: the reason that we accept THEN ABORT as a terminator for
1699      --  the sequence of statements is for error recovery which allows
1700      --  for misuse of an accept statement as a triggering statement.
1701
1702      Set_Statements
1703        (Accept_Alt_Node, P_Sequence_Of_Statements (SS_Eltm_Ortm_Tatm));
1704      return Accept_Alt_Node;
1705   end P_Accept_Alternative;
1706
1707   ------------------------------
1708   -- 9.7.1  Delay Alternative --
1709   ------------------------------
1710
1711   --  DELAY_ALTERNATIVE ::=
1712   --    DELAY_STATEMENT [SEQUENCE_OF_STATEMENTS]
1713
1714   --  Error_Recovery: Cannot raise Error_Resync
1715
1716   --  Note: the caller is responsible for setting the Pragmas_Before
1717   --  field of the returned N_Terminate_Alternative node.
1718
1719   function P_Delay_Alternative return Node_Id is
1720      Delay_Alt_Node : Node_Id;
1721
1722   begin
1723      Delay_Alt_Node := New_Node (N_Delay_Alternative, Token_Ptr);
1724      Set_Delay_Statement (Delay_Alt_Node, P_Delay_Statement);
1725
1726      --  Note: the reason that we accept THEN ABORT as a terminator for
1727      --  the sequence of statements is for error recovery which allows
1728      --  for misuse of an accept statement as a triggering statement.
1729
1730      Set_Statements
1731        (Delay_Alt_Node, P_Sequence_Of_Statements (SS_Eltm_Ortm_Tatm));
1732      return Delay_Alt_Node;
1733   end P_Delay_Alternative;
1734
1735   ----------------------------------
1736   -- 9.7.1  Terminate Alternative --
1737   ----------------------------------
1738
1739   --  TERMINATE_ALTERNATIVE ::= terminate;
1740
1741   --  Error_Recovery: Cannot raise Error_Resync
1742
1743   --  Note: the caller is responsible for setting the Pragmas_Before
1744   --  field of the returned N_Terminate_Alternative node.
1745
1746   function P_Terminate_Alternative return Node_Id is
1747      Terminate_Alt_Node : Node_Id;
1748
1749   begin
1750      Terminate_Alt_Node := New_Node (N_Terminate_Alternative, Token_Ptr);
1751      Scan; -- past TERMINATE
1752      TF_Semicolon;
1753
1754      --  For all other select alternatives, the sequence of statements
1755      --  after the alternative statement will swallow up any pragmas
1756      --  coming in this position. But the terminate alternative has no
1757      --  sequence of statements, so the pragmas here must be treated
1758      --  specially.
1759
1760      Set_Pragmas_After (Terminate_Alt_Node, P_Pragmas_Opt);
1761      return Terminate_Alt_Node;
1762   end P_Terminate_Alternative;
1763
1764   -----------------------------
1765   -- 9.7.2  Timed Entry Call --
1766   -----------------------------
1767
1768   --  Parsed by P_Select_Statement (9.7)
1769
1770   -----------------------------------
1771   -- 9.7.2  Entry Call Alternative --
1772   -----------------------------------
1773
1774   --  Parsed by P_Select_Statement (9.7)
1775
1776   -----------------------------------
1777   -- 9.7.3  Conditional Entry Call --
1778   -----------------------------------
1779
1780   --  Parsed by P_Select_Statement (9.7)
1781
1782   --------------------------------
1783   -- 9.7.4  Asynchronous Select --
1784   --------------------------------
1785
1786   --  Parsed by P_Select_Statement (9.7)
1787
1788   -----------------------------------
1789   -- 9.7.4  Triggering Alternative --
1790   -----------------------------------
1791
1792   --  Parsed by P_Select_Statement (9.7)
1793
1794   ---------------------------------
1795   -- 9.7.4  Triggering Statement --
1796   ---------------------------------
1797
1798   --  Parsed by P_Select_Statement (9.7)
1799
1800   ---------------------------
1801   -- 9.7.4  Abortable Part --
1802   ---------------------------
1803
1804   --  ABORTABLE_PART ::= SEQUENCE_OF_STATEMENTS
1805
1806   --  The caller has verified that THEN ABORT is present, and Token is
1807   --  pointing to the ABORT on entry (or if not, then we have an error)
1808
1809   --  Error recovery: cannot raise Error_Resync
1810
1811   function P_Abortable_Part return Node_Id is
1812      Abortable_Part_Node : Node_Id;
1813
1814   begin
1815      Abortable_Part_Node := New_Node (N_Abortable_Part, Token_Ptr);
1816      T_Abort; -- scan past ABORT
1817
1818      if Ada_Version = Ada_83 then
1819         Error_Msg_SP ("(Ada 83) asynchronous select not allowed!");
1820      end if;
1821
1822      Set_Statements (Abortable_Part_Node, P_Sequence_Of_Statements (SS_Sreq));
1823      return Abortable_Part_Node;
1824   end P_Abortable_Part;
1825
1826   --------------------------
1827   -- 9.8  Abort Statement --
1828   --------------------------
1829
1830   --  ABORT_STATEMENT ::= abort task_NAME {, task_NAME};
1831
1832   --  The caller has checked that the initial token is ABORT
1833
1834   --  Error recovery: cannot raise Error_Resync
1835
1836   function P_Abort_Statement return Node_Id is
1837      Abort_Node : Node_Id;
1838
1839   begin
1840      Abort_Node := New_Node (N_Abort_Statement, Token_Ptr);
1841      Scan; -- past ABORT
1842      Set_Names (Abort_Node, New_List);
1843
1844      loop
1845         Append (P_Name, Names (Abort_Node));
1846         exit when Token /= Tok_Comma;
1847         Scan; -- past comma
1848      end loop;
1849
1850      TF_Semicolon;
1851      return Abort_Node;
1852   end P_Abort_Statement;
1853
1854end Ch9;
1855