OpenCores
URL https://opencores.org/ocsvn/openrisc_2011-10-31/openrisc_2011-10-31/trunk

Subversion Repositories openrisc_2011-10-31

[/] [openrisc/] [trunk/] [gnu-src/] [gcc-4.5.1/] [gcc/] [ada/] [par-ch3.adb] - Blame information for rev 284

Go to most recent revision | Details | Compare with Previous | View Log

Line No. Rev Author Line
1 281 jeremybenn
------------------------------------------------------------------------------
2
--                                                                          --
3
--                         GNAT COMPILER COMPONENTS                         --
4
--                                                                          --
5
--                              P A R . C H 3                               --
6
--                                                                          --
7
--                                 B o d y                                  --
8
--                                                                          --
9
--          Copyright (C) 1992-2009, 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
 
26
pragma Style_Checks (All_Checks);
27
--  Turn off subprogram body ordering check. Subprograms are in order
28
--  by RM section rather than alphabetical.
29
 
30
with Sinfo.CN; use Sinfo.CN;
31
 
32
separate (Par)
33
 
34
---------
35
-- Ch3 --
36
---------
37
 
38
package body Ch3 is
39
 
40
   -----------------------
41
   -- Local Subprograms --
42
   -----------------------
43
 
44
   function P_Component_List                               return Node_Id;
45
   function P_Defining_Character_Literal                   return Node_Id;
46
   function P_Delta_Constraint                             return Node_Id;
47
   function P_Derived_Type_Def_Or_Private_Ext_Decl         return Node_Id;
48
   function P_Digits_Constraint                            return Node_Id;
49
   function P_Discriminant_Association                     return Node_Id;
50
   function P_Enumeration_Literal_Specification            return Node_Id;
51
   function P_Enumeration_Type_Definition                  return Node_Id;
52
   function P_Fixed_Point_Definition                       return Node_Id;
53
   function P_Floating_Point_Definition                    return Node_Id;
54
   function P_Index_Or_Discriminant_Constraint             return Node_Id;
55
   function P_Real_Range_Specification_Opt                 return Node_Id;
56
   function P_Subtype_Declaration                          return Node_Id;
57
   function P_Type_Declaration                             return Node_Id;
58
   function P_Modular_Type_Definition                      return Node_Id;
59
   function P_Variant                                      return Node_Id;
60
   function P_Variant_Part                                 return Node_Id;
61
 
62
   procedure Check_Restricted_Expression (N : Node_Id);
63
   --  Check that the expression N meets the Restricted_Expression syntax.
64
   --  The syntax is as follows:
65
   --
66
   --    RESTRICTED_EXPRESSION ::=
67
   --        RESTRICTED_RELATION {and RESTRICTED_RELATION}
68
   --      | RESTRICTED_RELATION {and then RESTRICTED_RELATION}
69
   --      | RESTRICTED_RELATION {or RESTRICTED_RELATION}
70
   --      | RESTRICTED_RELATION {or else RESTRICTED_RELATION}
71
   --      | RESTRICTED_RELATION {xor RESTRICTED_RELATION}
72
   --
73
   --    RESTRICTED_RELATION ::=
74
   --       SIMPLE_EXPRESSION [RELATIONAL_OPERATOR SIMPLE_EXPRESSION]
75
   --
76
   --  This syntax is used for choices when extensions (and set notations)
77
   --  are enabled, to remove the ambiguity of "when X in A | B". We consider
78
   --  it very unlikely that this will ever arise in practice.
79
 
80
   procedure P_Declarative_Items
81
     (Decls   : List_Id;
82
      Done    : out Boolean;
83
      In_Spec : Boolean);
84
   --  Scans out a single declarative item, or, in the case of a declaration
85
   --  with a list of identifiers, a list of declarations, one for each of the
86
   --  identifiers in the list. The declaration or declarations scanned are
87
   --  appended to the given list. Done indicates whether or not there may be
88
   --  additional declarative items to scan. If Done is True, then a decision
89
   --  has been made that there are no more items to scan. If Done is False,
90
   --  then there may be additional declarations to scan. In_Spec is true if
91
   --  we are scanning a package declaration, and is used to generate an
92
   --  appropriate message if a statement is encountered in such a context.
93
 
94
   procedure P_Identifier_Declarations
95
     (Decls   : List_Id;
96
      Done    : out Boolean;
97
      In_Spec : Boolean);
98
   --  Scans out a set of declarations for an identifier or list of
99
   --  identifiers, and appends them to the given list. The parameters have
100
   --  the same significance as for P_Declarative_Items.
101
 
102
   procedure Statement_When_Declaration_Expected
103
     (Decls   : List_Id;
104
      Done    : out Boolean;
105
      In_Spec : Boolean);
106
   --  Called when a statement is found at a point where a declaration was
107
   --  expected. The parameters are as described for P_Declarative_Items.
108
 
109
   procedure Set_Declaration_Expected;
110
   --  Posts a "declaration expected" error messages at the start of the
111
   --  current token, and if this is the first such message issued, saves
112
   --  the message id in Missing_Begin_Msg, for possible later replacement.
113
 
114
 
115
   ---------------------------------
116
   -- Check_Restricted_Expression --
117
   ---------------------------------
118
 
119
   procedure Check_Restricted_Expression (N : Node_Id) is
120
   begin
121
      if Nkind_In (N, N_Op_And, N_Op_Or, N_Op_Xor, N_And_Then, N_Or_Else) then
122
         Check_Restricted_Expression (Left_Opnd (N));
123
         Check_Restricted_Expression (Right_Opnd (N));
124
 
125
      elsif Nkind_In (N, N_In, N_Not_In)
126
        and then Paren_Count (N) = 0
127
      then
128
         Error_Msg_N
129
           ("|this expression must be parenthesized!", N);
130
         Error_Msg_N
131
           ("\|since extensions (and set notation) are allowed", N);
132
      end if;
133
   end Check_Restricted_Expression;
134
 
135
   -------------------
136
   -- Init_Expr_Opt --
137
   -------------------
138
 
139
   function Init_Expr_Opt (P : Boolean := False) return Node_Id is
140
   begin
141
      --  For colon, assume it means := unless it is at the end of
142
      --  a line, in which case guess that it means a semicolon.
143
 
144
      if Token = Tok_Colon then
145
         if Token_Is_At_End_Of_Line then
146
            T_Semicolon;
147
            return Empty;
148
         end if;
149
 
150
      --  Here if := or something that we will take as equivalent
151
 
152
      elsif Token = Tok_Colon_Equal
153
        or else Token = Tok_Equal
154
        or else Token = Tok_Is
155
      then
156
         null;
157
 
158
      --  Another possibility. If we have a literal followed by a semicolon,
159
      --  we assume that we have a missing colon-equal.
160
 
161
      elsif Token in Token_Class_Literal then
162
         declare
163
            Scan_State : Saved_Scan_State;
164
 
165
         begin
166
            Save_Scan_State (Scan_State);
167
            Scan; -- past literal or identifier
168
 
169
            if Token = Tok_Semicolon then
170
               Restore_Scan_State (Scan_State);
171
            else
172
               Restore_Scan_State (Scan_State);
173
               return Empty;
174
            end if;
175
         end;
176
 
177
      --  Otherwise we definitely have no initialization expression
178
 
179
      else
180
         return Empty;
181
      end if;
182
 
183
      --  Merge here if we have an initialization expression
184
 
185
      T_Colon_Equal;
186
 
187
      if P then
188
         return P_Expression;
189
      else
190
         return P_Expression_No_Right_Paren;
191
      end if;
192
   end Init_Expr_Opt;
193
 
194
   ----------------------------
195
   -- 3.1  Basic Declaration --
196
   ----------------------------
197
 
198
   --  Parsed by P_Basic_Declarative_Items (3.9)
199
 
200
   ------------------------------
201
   -- 3.1  Defining Identifier --
202
   ------------------------------
203
 
204
   --  DEFINING_IDENTIFIER ::= IDENTIFIER
205
 
206
   --  Error recovery: can raise Error_Resync
207
 
208
   function P_Defining_Identifier (C : Id_Check := None) return Node_Id is
209
      Ident_Node : Node_Id;
210
 
211
   begin
212
      --  Scan out the identifier. Note that this code is essentially identical
213
      --  to P_Identifier, except that in the call to Scan_Reserved_Identifier
214
      --  we set Force_Msg to True, since we want at least one message for each
215
      --  separate declaration (but not use) of a reserved identifier.
216
 
217
      if Token = Tok_Identifier then
218
 
219
         --  Ada 2005 (AI-284): Compiling in Ada95 mode we warn that INTERFACE,
220
         --  OVERRIDING, and SYNCHRONIZED are new reserved words. Note that
221
         --  in the case where these keywords are misused in Ada 95 mode,
222
         --  this routine will generally not be called at all.
223
 
224
         if Ada_Version = Ada_95
225
           and then Warn_On_Ada_2005_Compatibility
226
         then
227
            if Token_Name = Name_Overriding
228
              or else Token_Name = Name_Synchronized
229
              or else (Token_Name = Name_Interface
230
                        and then Prev_Token /= Tok_Pragma)
231
            then
232
               Error_Msg_N ("& is a reserved word in Ada 2005?", Token_Node);
233
            end if;
234
         end if;
235
 
236
      --  If we have a reserved identifier, manufacture an identifier with
237
      --  a corresponding name after posting an appropriate error message
238
 
239
      elsif Is_Reserved_Identifier (C) then
240
         Scan_Reserved_Identifier (Force_Msg => True);
241
 
242
      --  Otherwise we have junk that cannot be interpreted as an identifier
243
 
244
      else
245
         T_Identifier; -- to give message
246
         raise Error_Resync;
247
      end if;
248
 
249
      Ident_Node := Token_Node;
250
      Scan; -- past the reserved identifier
251
 
252
      --  If we already have a defining identifier, clean it out and make
253
      --  a new clean identifier. This situation arises in some error cases
254
      --  and we need to fix it.
255
 
256
      if Nkind (Ident_Node) = N_Defining_Identifier then
257
         Ident_Node :=
258
           Make_Identifier (Sloc (Ident_Node),
259
             Chars => Chars (Ident_Node));
260
      end if;
261
 
262
      --  Change identifier to defining identifier if not in error
263
 
264
      if Ident_Node /= Error then
265
         Change_Identifier_To_Defining_Identifier (Ident_Node);
266
      end if;
267
 
268
      return Ident_Node;
269
   end P_Defining_Identifier;
270
 
271
   -----------------------------
272
   -- 3.2.1  Type Declaration --
273
   -----------------------------
274
 
275
   --  TYPE_DECLARATION ::=
276
   --    FULL_TYPE_DECLARATION
277
   --  | INCOMPLETE_TYPE_DECLARATION
278
   --  | PRIVATE_TYPE_DECLARATION
279
   --  | PRIVATE_EXTENSION_DECLARATION
280
 
281
   --  FULL_TYPE_DECLARATION ::=
282
   --    type DEFINING_IDENTIFIER [KNOWN_DISCRIMINANT_PART] is TYPE_DEFINITION;
283
   --  | CONCURRENT_TYPE_DECLARATION
284
 
285
   --  INCOMPLETE_TYPE_DECLARATION ::=
286
   --    type DEFINING_IDENTIFIER [DISCRIMINANT_PART] [is tagged];
287
 
288
   --  PRIVATE_TYPE_DECLARATION ::=
289
   --    type DEFINING_IDENTIFIER [DISCRIMINANT_PART]
290
   --      is [abstract] [tagged] [limited] private;
291
 
292
   --  PRIVATE_EXTENSION_DECLARATION ::=
293
   --    type DEFINING_IDENTIFIER [DISCRIMINANT_PART] is
294
   --      [abstract] [limited | synchronized]
295
   --        new ancestor_SUBTYPE_INDICATION [and INTERFACE_LIST]
296
   --          with private;
297
 
298
   --  TYPE_DEFINITION ::=
299
   --    ENUMERATION_TYPE_DEFINITION  | INTEGER_TYPE_DEFINITION
300
   --  | REAL_TYPE_DEFINITION         | ARRAY_TYPE_DEFINITION
301
   --  | RECORD_TYPE_DEFINITION       | ACCESS_TYPE_DEFINITION
302
   --  | DERIVED_TYPE_DEFINITION      | INTERFACE_TYPE_DEFINITION
303
 
304
   --  INTEGER_TYPE_DEFINITION ::=
305
   --    SIGNED_INTEGER_TYPE_DEFINITION
306
   --    MODULAR_TYPE_DEFINITION
307
 
308
   --  INTERFACE_TYPE_DEFINITION ::=
309
   --    [limited | task | protected | synchronized ] interface
310
   --      [and INTERFACE_LIST]
311
 
312
   --  Error recovery: can raise Error_Resync
313
 
314
   --  Note: The processing for full type declaration, incomplete type
315
   --  declaration, private type declaration and type definition is
316
   --  included in this function. The processing for concurrent type
317
   --  declarations is NOT here, but rather in chapter 9 (i.e. this
318
   --  function handles only declarations starting with TYPE).
319
 
320
   function P_Type_Declaration return Node_Id is
321
      Abstract_Present : Boolean := False;
322
      Abstract_Loc     : Source_Ptr := No_Location;
323
      Decl_Node        : Node_Id;
324
      Discr_List       : List_Id;
325
      Discr_Sloc       : Source_Ptr;
326
      End_Labl         : Node_Id;
327
      Ident_Node       : Node_Id;
328
      Is_Derived_Iface : Boolean := False;
329
      Type_Loc         : Source_Ptr;
330
      Type_Start_Col   : Column_Number;
331
      Unknown_Dis      : Boolean;
332
 
333
      Typedef_Node     : Node_Id;
334
      --  Normally holds type definition, except in the case of a private
335
      --  extension declaration, in which case it holds the declaration itself
336
 
337
   begin
338
      Type_Loc := Token_Ptr;
339
      Type_Start_Col := Start_Column;
340
 
341
      --  If we have TYPE, then proceed ahead and scan identifier
342
 
343
      if Token = Tok_Type then
344
         Type_Token_Location := Type_Loc;
345
         Scan; -- past TYPE
346
         Ident_Node := P_Defining_Identifier (C_Is);
347
 
348
      --  Otherwise this is an error case
349
 
350
      else
351
         T_Type;
352
         Type_Token_Location := Type_Loc;
353
         Ident_Node := P_Defining_Identifier (C_Is);
354
      end if;
355
 
356
      Discr_Sloc := Token_Ptr;
357
 
358
      if P_Unknown_Discriminant_Part_Opt then
359
         Unknown_Dis := True;
360
         Discr_List := No_List;
361
      else
362
         Unknown_Dis := False;
363
         Discr_List := P_Known_Discriminant_Part_Opt;
364
      end if;
365
 
366
      --  Incomplete type declaration. We complete the processing for this
367
      --  case here and return the resulting incomplete type declaration node
368
 
369
      if Token = Tok_Semicolon then
370
         Scan; -- past ;
371
         Decl_Node := New_Node (N_Incomplete_Type_Declaration, Type_Loc);
372
         Set_Defining_Identifier (Decl_Node, Ident_Node);
373
         Set_Unknown_Discriminants_Present (Decl_Node, Unknown_Dis);
374
         Set_Discriminant_Specifications (Decl_Node, Discr_List);
375
         return Decl_Node;
376
 
377
      else
378
         Decl_Node := Empty;
379
      end if;
380
 
381
      --  Full type declaration or private type declaration, must have IS
382
 
383
      if Token = Tok_Equal then
384
         TF_Is;
385
         Scan; -- past = used in place of IS
386
 
387
      elsif Token = Tok_Renames then
388
         Error_Msg_SC ("RENAMES should be IS");
389
         Scan; -- past RENAMES used in place of IS
390
 
391
      else
392
         TF_Is;
393
      end if;
394
 
395
      --  First an error check, if we have two identifiers in a row, a likely
396
      --  possibility is that the first of the identifiers is an incorrectly
397
      --  spelled keyword.
398
 
399
      if Token = Tok_Identifier then
400
         declare
401
            SS : Saved_Scan_State;
402
            I2 : Boolean;
403
 
404
         begin
405
            Save_Scan_State (SS);
406
            Scan; -- past initial identifier
407
            I2 := (Token = Tok_Identifier);
408
            Restore_Scan_State (SS);
409
 
410
            if I2
411
              and then
412
                (Bad_Spelling_Of (Tok_Abstract) or else
413
                 Bad_Spelling_Of (Tok_Access)   or else
414
                 Bad_Spelling_Of (Tok_Aliased)  or else
415
                 Bad_Spelling_Of (Tok_Constant))
416
            then
417
               null;
418
            end if;
419
         end;
420
      end if;
421
 
422
      --  Check for misuse of Ada 95 keyword abstract in Ada 83 mode
423
 
424
      if Token_Name = Name_Abstract then
425
         Check_95_Keyword (Tok_Abstract, Tok_Tagged);
426
         Check_95_Keyword (Tok_Abstract, Tok_New);
427
      end if;
428
 
429
      --  Check cases of misuse of ABSTRACT
430
 
431
      if Token = Tok_Abstract then
432
         Abstract_Present := True;
433
         Abstract_Loc     := Token_Ptr;
434
         Scan; -- past ABSTRACT
435
 
436
         --  Ada 2005 (AI-419): AARM 3.4 (2/2)
437
 
438
         if (Ada_Version < Ada_05 and then Token = Tok_Limited)
439
           or else Token = Tok_Private
440
           or else Token = Tok_Record
441
           or else Token = Tok_Null
442
         then
443
            Error_Msg_AP ("TAGGED expected");
444
         end if;
445
      end if;
446
 
447
      --  Check for misuse of Ada 95 keyword Tagged
448
 
449
      if Token_Name = Name_Tagged then
450
         Check_95_Keyword (Tok_Tagged, Tok_Private);
451
         Check_95_Keyword (Tok_Tagged, Tok_Limited);
452
         Check_95_Keyword (Tok_Tagged, Tok_Record);
453
      end if;
454
 
455
      --  Special check for misuse of Aliased
456
 
457
      if Token = Tok_Aliased or else Token_Name = Name_Aliased then
458
         Error_Msg_SC ("ALIASED not allowed in type definition");
459
         Scan; -- past ALIASED
460
      end if;
461
 
462
      --  The following processing deals with either a private type declaration
463
      --  or a full type declaration. In the private type case, we build the
464
      --  N_Private_Type_Declaration node, setting its Tagged_Present and
465
      --  Limited_Present flags, on encountering the Private keyword, and
466
      --  leave Typedef_Node set to Empty. For the full type declaration
467
      --  case, Typedef_Node gets set to the type definition.
468
 
469
      Typedef_Node := Empty;
470
 
471
      --  Switch on token following the IS. The loop normally runs once. It
472
      --  only runs more than once if an error is detected, to try again after
473
      --  detecting and fixing up the error.
474
 
475
      loop
476
         case Token is
477
 
478
            when Tok_Access |
479
                 Tok_Not    => --  Ada 2005 (AI-231)
480
               Typedef_Node := P_Access_Type_Definition;
481
               TF_Semicolon;
482
               exit;
483
 
484
            when Tok_Array =>
485
               Typedef_Node := P_Array_Type_Definition;
486
               TF_Semicolon;
487
               exit;
488
 
489
            when Tok_Delta =>
490
               Typedef_Node := P_Fixed_Point_Definition;
491
               TF_Semicolon;
492
               exit;
493
 
494
            when Tok_Digits =>
495
               Typedef_Node := P_Floating_Point_Definition;
496
               TF_Semicolon;
497
               exit;
498
 
499
            when Tok_In =>
500
               Ignore (Tok_In);
501
 
502
            when Tok_Integer_Literal =>
503
               T_Range;
504
               Typedef_Node := P_Signed_Integer_Type_Definition;
505
               TF_Semicolon;
506
               exit;
507
 
508
            when Tok_Null =>
509
               Typedef_Node := P_Record_Definition;
510
               TF_Semicolon;
511
               exit;
512
 
513
            when Tok_Left_Paren =>
514
               Typedef_Node := P_Enumeration_Type_Definition;
515
 
516
               End_Labl :=
517
                 Make_Identifier (Token_Ptr,
518
                   Chars => Chars (Ident_Node));
519
               Set_Comes_From_Source (End_Labl, False);
520
 
521
               Set_End_Label (Typedef_Node, End_Labl);
522
               TF_Semicolon;
523
               exit;
524
 
525
            when Tok_Mod =>
526
               Typedef_Node := P_Modular_Type_Definition;
527
               TF_Semicolon;
528
               exit;
529
 
530
            when Tok_New =>
531
               Typedef_Node := P_Derived_Type_Def_Or_Private_Ext_Decl;
532
 
533
               if Nkind (Typedef_Node) = N_Derived_Type_Definition
534
                 and then Present (Record_Extension_Part (Typedef_Node))
535
               then
536
                  End_Labl :=
537
                    Make_Identifier (Token_Ptr,
538
                      Chars => Chars (Ident_Node));
539
                  Set_Comes_From_Source (End_Labl, False);
540
 
541
                  Set_End_Label
542
                    (Record_Extension_Part (Typedef_Node), End_Labl);
543
               end if;
544
 
545
               TF_Semicolon;
546
               exit;
547
 
548
            when Tok_Range =>
549
               Typedef_Node := P_Signed_Integer_Type_Definition;
550
               TF_Semicolon;
551
               exit;
552
 
553
            when Tok_Record =>
554
               Typedef_Node := P_Record_Definition;
555
 
556
               End_Labl :=
557
                 Make_Identifier (Token_Ptr,
558
                   Chars => Chars (Ident_Node));
559
               Set_Comes_From_Source (End_Labl, False);
560
 
561
               Set_End_Label (Typedef_Node, End_Labl);
562
               TF_Semicolon;
563
               exit;
564
 
565
            when Tok_Tagged =>
566
               Scan; -- past TAGGED
567
 
568
               --  Ada 2005 (AI-326): If the words IS TAGGED appear, the type
569
               --  is a tagged incomplete type.
570
 
571
               if Ada_Version >= Ada_05
572
                 and then Token = Tok_Semicolon
573
               then
574
                  Scan; -- past ;
575
 
576
                  Decl_Node :=
577
                    New_Node (N_Incomplete_Type_Declaration, Type_Loc);
578
                  Set_Defining_Identifier           (Decl_Node, Ident_Node);
579
                  Set_Tagged_Present                (Decl_Node);
580
                  Set_Unknown_Discriminants_Present (Decl_Node, Unknown_Dis);
581
                  Set_Discriminant_Specifications   (Decl_Node, Discr_List);
582
 
583
                  return Decl_Node;
584
               end if;
585
 
586
               if Token = Tok_Abstract then
587
                  Error_Msg_SC -- CODEFIX
588
                    ("ABSTRACT must come before TAGGED");
589
                  Abstract_Present := True;
590
                  Abstract_Loc := Token_Ptr;
591
                  Scan; -- past ABSTRACT
592
               end if;
593
 
594
               if Token = Tok_Limited then
595
                  Scan; -- past LIMITED
596
 
597
                  --  TAGGED LIMITED PRIVATE case
598
 
599
                  if Token = Tok_Private then
600
                     Decl_Node :=
601
                       New_Node (N_Private_Type_Declaration, Type_Loc);
602
                     Set_Tagged_Present (Decl_Node, True);
603
                     Set_Limited_Present (Decl_Node, True);
604
                     Scan; -- past PRIVATE
605
 
606
                  --  TAGGED LIMITED RECORD
607
 
608
                  else
609
                     Typedef_Node := P_Record_Definition;
610
                     Set_Tagged_Present (Typedef_Node, True);
611
                     Set_Limited_Present (Typedef_Node, True);
612
 
613
                     End_Labl :=
614
                       Make_Identifier (Token_Ptr,
615
                         Chars => Chars (Ident_Node));
616
                     Set_Comes_From_Source (End_Labl, False);
617
 
618
                     Set_End_Label (Typedef_Node, End_Labl);
619
                  end if;
620
 
621
               else
622
                  --  TAGGED PRIVATE
623
 
624
                  if Token = Tok_Private then
625
                     Decl_Node :=
626
                       New_Node (N_Private_Type_Declaration, Type_Loc);
627
                     Set_Tagged_Present (Decl_Node, True);
628
                     Scan; -- past PRIVATE
629
 
630
                  --  TAGGED RECORD
631
 
632
                  else
633
                     Typedef_Node := P_Record_Definition;
634
                     Set_Tagged_Present (Typedef_Node, True);
635
 
636
                     End_Labl :=
637
                       Make_Identifier (Token_Ptr,
638
                         Chars => Chars (Ident_Node));
639
                     Set_Comes_From_Source (End_Labl, False);
640
 
641
                     Set_End_Label (Typedef_Node, End_Labl);
642
                  end if;
643
               end if;
644
 
645
               TF_Semicolon;
646
               exit;
647
 
648
            when Tok_Limited =>
649
               Scan; -- past LIMITED
650
 
651
               loop
652
                  if Token = Tok_Tagged then
653
                     Error_Msg_SC -- CODEFIX
654
                       ("TAGGED must come before LIMITED");
655
                     Scan; -- past TAGGED
656
 
657
                  elsif Token = Tok_Abstract then
658
                     Error_Msg_SC -- CODEFIX
659
                       ("ABSTRACT must come before LIMITED");
660
                     Scan; -- past ABSTRACT
661
 
662
                  else
663
                     exit;
664
                  end if;
665
               end loop;
666
 
667
               --  LIMITED RECORD or LIMITED NULL RECORD
668
 
669
               if Token = Tok_Record or else Token = Tok_Null then
670
                  if Ada_Version = Ada_83 then
671
                     Error_Msg_SP
672
                       ("(Ada 83) limited record declaration not allowed!");
673
 
674
                  --  In Ada2005, "abstract limited" can appear before "new",
675
                  --  but it cannot be part of an untagged record declaration.
676
 
677
                  elsif Abstract_Present
678
                    and then Prev_Token /= Tok_Tagged
679
                  then
680
                     Error_Msg_SP ("TAGGED expected");
681
                  end if;
682
 
683
                  Typedef_Node := P_Record_Definition;
684
                  Set_Limited_Present (Typedef_Node, True);
685
 
686
               --  Ada 2005 (AI-251): LIMITED INTERFACE
687
 
688
               --  If we are compiling in Ada 83 or Ada 95 mode, "interface"
689
               --  is not a reserved word but we force its analysis to
690
               --  generate the corresponding usage error.
691
 
692
               elsif Token = Tok_Interface
693
                 or else (Token = Tok_Identifier
694
                           and then Chars (Token_Node) = Name_Interface)
695
               then
696
                  Typedef_Node :=
697
                    P_Interface_Type_Definition (Abstract_Present);
698
                  Abstract_Present := True;
699
                  Set_Limited_Present (Typedef_Node);
700
 
701
                  if Nkind (Typedef_Node) = N_Derived_Type_Definition then
702
                     Is_Derived_Iface := True;
703
                  end if;
704
 
705
                  --  Ada 2005 (AI-419): LIMITED NEW
706
 
707
               elsif Token = Tok_New then
708
                  if Ada_Version < Ada_05 then
709
                     Error_Msg_SP
710
                       ("LIMITED in derived type is an Ada 2005 extension");
711
                     Error_Msg_SP
712
                       ("\unit must be compiled with -gnat05 switch");
713
                  end if;
714
 
715
                  Typedef_Node := P_Derived_Type_Def_Or_Private_Ext_Decl;
716
                  Set_Limited_Present (Typedef_Node);
717
 
718
                  if Nkind (Typedef_Node) = N_Derived_Type_Definition
719
                    and then Present (Record_Extension_Part (Typedef_Node))
720
                  then
721
                     End_Labl :=
722
                       Make_Identifier (Token_Ptr,
723
                                        Chars => Chars (Ident_Node));
724
                     Set_Comes_From_Source (End_Labl, False);
725
 
726
                     Set_End_Label
727
                       (Record_Extension_Part (Typedef_Node), End_Labl);
728
                  end if;
729
 
730
               --  LIMITED PRIVATE is the only remaining possibility here
731
 
732
               else
733
                  Decl_Node := New_Node (N_Private_Type_Declaration, Type_Loc);
734
                  Set_Limited_Present (Decl_Node, True);
735
                  T_Private; -- past PRIVATE (or complain if not there!)
736
               end if;
737
 
738
               TF_Semicolon;
739
               exit;
740
 
741
            --  Here we have an identifier after the IS, which is certainly
742
            --  wrong and which might be one of several different mistakes.
743
 
744
            when Tok_Identifier =>
745
 
746
               --  First case, if identifier is on same line, then probably we
747
               --  have something like "type X is Integer .." and the best
748
               --  diagnosis is a missing NEW. Note: the missing new message
749
               --  will be posted by P_Derived_Type_Def_Or_Private_Ext_Decl.
750
 
751
               if not Token_Is_At_Start_Of_Line then
752
                  Typedef_Node := P_Derived_Type_Def_Or_Private_Ext_Decl;
753
                  TF_Semicolon;
754
 
755
               --  If the identifier is at the start of the line, and is in the
756
               --  same column as the type declaration itself then we consider
757
               --  that we had a missing type definition on the previous line
758
 
759
               elsif Start_Column <= Type_Start_Col then
760
                  Error_Msg_AP ("type definition expected");
761
                  Typedef_Node := Error;
762
 
763
               --  If the identifier is at the start of the line, and is in
764
               --  a column to the right of the type declaration line, then we
765
               --  may have something like:
766
 
767
               --    type x is
768
               --       r : integer
769
 
770
               --  and the best diagnosis is a missing record keyword
771
 
772
               else
773
                  Typedef_Node := P_Record_Definition;
774
                  TF_Semicolon;
775
               end if;
776
 
777
               exit;
778
 
779
            --  Ada 2005 (AI-251): INTERFACE
780
 
781
            when Tok_Interface =>
782
               Typedef_Node := P_Interface_Type_Definition (Abstract_Present);
783
               Abstract_Present := True;
784
               TF_Semicolon;
785
               exit;
786
 
787
            when Tok_Private =>
788
               Decl_Node := New_Node (N_Private_Type_Declaration, Type_Loc);
789
               Scan; -- past PRIVATE
790
               TF_Semicolon;
791
               exit;
792
 
793
            --  Ada 2005 (AI-345): Protected, synchronized or task interface
794
            --  or Ada 2005 (AI-443): Synchronized private extension.
795
 
796
            when Tok_Protected    |
797
                 Tok_Synchronized |
798
                 Tok_Task         =>
799
 
800
               declare
801
                  Saved_Token : constant Token_Type := Token;
802
 
803
               begin
804
                  Scan; -- past TASK, PROTECTED or SYNCHRONIZED
805
 
806
                  --  Synchronized private extension
807
 
808
                  if Token = Tok_New then
809
                     Typedef_Node := P_Derived_Type_Def_Or_Private_Ext_Decl;
810
 
811
                     if Saved_Token = Tok_Synchronized then
812
                        if Nkind (Typedef_Node) =
813
                          N_Derived_Type_Definition
814
                        then
815
                           Error_Msg_N
816
                             ("SYNCHRONIZED not allowed for record extension",
817
                              Typedef_Node);
818
                        else
819
                           Set_Synchronized_Present (Typedef_Node);
820
                        end if;
821
 
822
                     else
823
                        Error_Msg_SC ("invalid kind of private extension");
824
                     end if;
825
 
826
                  --  Interface
827
 
828
                  else
829
                     if Token /= Tok_Interface then
830
                        Error_Msg_SC ("NEW or INTERFACE expected");
831
                     end if;
832
 
833
                     Typedef_Node :=
834
                       P_Interface_Type_Definition (Abstract_Present);
835
                     Abstract_Present := True;
836
 
837
                     case Saved_Token is
838
                        when Tok_Task =>
839
                           Set_Task_Present         (Typedef_Node);
840
 
841
                        when Tok_Protected =>
842
                           Set_Protected_Present    (Typedef_Node);
843
 
844
                        when Tok_Synchronized =>
845
                           Set_Synchronized_Present (Typedef_Node);
846
 
847
                        when others =>
848
                           pragma Assert (False);
849
                           null;
850
                     end case;
851
                  end if;
852
               end;
853
 
854
               TF_Semicolon;
855
               exit;
856
 
857
            --  Anything else is an error
858
 
859
            when others =>
860
               if Bad_Spelling_Of (Tok_Access)
861
                    or else
862
                  Bad_Spelling_Of (Tok_Array)
863
                    or else
864
                  Bad_Spelling_Of (Tok_Delta)
865
                    or else
866
                  Bad_Spelling_Of (Tok_Digits)
867
                    or else
868
                  Bad_Spelling_Of (Tok_Limited)
869
                    or else
870
                  Bad_Spelling_Of (Tok_Private)
871
                    or else
872
                  Bad_Spelling_Of (Tok_Range)
873
                    or else
874
                  Bad_Spelling_Of (Tok_Record)
875
                    or else
876
                  Bad_Spelling_Of (Tok_Tagged)
877
               then
878
                  null;
879
 
880
               else
881
                  Error_Msg_AP ("type definition expected");
882
                  raise Error_Resync;
883
               end if;
884
 
885
         end case;
886
      end loop;
887
 
888
      --  For the private type declaration case, the private type declaration
889
      --  node has been built, with the Tagged_Present and Limited_Present
890
      --  flags set as needed, and Typedef_Node is left set to Empty.
891
 
892
      if No (Typedef_Node) then
893
         Set_Unknown_Discriminants_Present (Decl_Node, Unknown_Dis);
894
         Set_Abstract_Present (Decl_Node, Abstract_Present);
895
 
896
      --  For a private extension declaration, Typedef_Node contains the
897
      --  N_Private_Extension_Declaration node, which we now complete. Note
898
      --  that the private extension declaration, unlike a full type
899
      --  declaration, does permit unknown discriminants.
900
 
901
      elsif Nkind (Typedef_Node) = N_Private_Extension_Declaration then
902
         Decl_Node := Typedef_Node;
903
         Set_Sloc (Decl_Node, Type_Loc);
904
         Set_Unknown_Discriminants_Present (Decl_Node, Unknown_Dis);
905
         Set_Abstract_Present (Typedef_Node, Abstract_Present);
906
 
907
      --  In the full type declaration case, Typedef_Node has the type
908
      --  definition and here is where we build the full type declaration
909
      --  node. This is also where we check for improper use of an unknown
910
      --  discriminant part (not allowed for full type declaration).
911
 
912
      else
913
         if Nkind (Typedef_Node) = N_Record_Definition
914
           or else (Nkind (Typedef_Node) = N_Derived_Type_Definition
915
                      and then Present (Record_Extension_Part (Typedef_Node)))
916
           or else Is_Derived_Iface
917
         then
918
            Set_Abstract_Present (Typedef_Node, Abstract_Present);
919
 
920
         elsif Abstract_Present then
921
            Error_Msg ("ABSTRACT not allowed here, ignored", Abstract_Loc);
922
         end if;
923
 
924
         Decl_Node := New_Node (N_Full_Type_Declaration, Type_Loc);
925
         Set_Type_Definition (Decl_Node, Typedef_Node);
926
 
927
         if Unknown_Dis then
928
            Error_Msg
929
              ("Full type declaration cannot have unknown discriminants",
930
                Discr_Sloc);
931
         end if;
932
      end if;
933
 
934
      --  Remaining processing is common for all three cases
935
 
936
      Set_Defining_Identifier (Decl_Node, Ident_Node);
937
      Set_Discriminant_Specifications (Decl_Node, Discr_List);
938
      return Decl_Node;
939
   end P_Type_Declaration;
940
 
941
   ----------------------------------
942
   -- 3.2.1  Full Type Declaration --
943
   ----------------------------------
944
 
945
   --  Parsed by P_Type_Declaration (3.2.1)
946
 
947
   ----------------------------
948
   -- 3.2.1  Type Definition --
949
   ----------------------------
950
 
951
   --  Parsed by P_Type_Declaration (3.2.1)
952
 
953
   --------------------------------
954
   -- 3.2.2  Subtype Declaration --
955
   --------------------------------
956
 
957
   --  SUBTYPE_DECLARATION ::=
958
   --    subtype DEFINING_IDENTIFIER is [NULL_EXCLUSION] SUBTYPE_INDICATION;
959
 
960
   --  The caller has checked that the initial token is SUBTYPE
961
 
962
   --  Error recovery: can raise Error_Resync
963
 
964
   function P_Subtype_Declaration return Node_Id is
965
      Decl_Node        : Node_Id;
966
      Not_Null_Present : Boolean := False;
967
 
968
   begin
969
      Decl_Node := New_Node (N_Subtype_Declaration, Token_Ptr);
970
      Scan; -- past SUBTYPE
971
      Set_Defining_Identifier (Decl_Node, P_Defining_Identifier (C_Is));
972
      TF_Is;
973
 
974
      if Token = Tok_New then
975
         Error_Msg_SC ("NEW ignored (only allowed in type declaration)");
976
         Scan; -- past NEW
977
      end if;
978
 
979
      Not_Null_Present := P_Null_Exclusion; --  Ada 2005 (AI-231)
980
      Set_Null_Exclusion_Present (Decl_Node, Not_Null_Present);
981
 
982
      Set_Subtype_Indication
983
        (Decl_Node, P_Subtype_Indication (Not_Null_Present));
984
      TF_Semicolon;
985
      return Decl_Node;
986
   end P_Subtype_Declaration;
987
 
988
   -------------------------------
989
   -- 3.2.2  Subtype Indication --
990
   -------------------------------
991
 
992
   --  SUBTYPE_INDICATION ::=
993
   --    [not null] SUBTYPE_MARK [CONSTRAINT]
994
 
995
   --  Error recovery: can raise Error_Resync
996
 
997
   function P_Null_Exclusion
998
     (Allow_Anonymous_In_95 : Boolean := False) return Boolean
999
   is
1000
      Not_Loc : constant Source_Ptr := Token_Ptr;
1001
      --  Source position of "not", if present
1002
 
1003
   begin
1004
      if Token /= Tok_Not then
1005
         return False;
1006
 
1007
      else
1008
         Scan; --  past NOT
1009
 
1010
         if Token = Tok_Null then
1011
            Scan; --  past NULL
1012
 
1013
            --  Ada 2005 (AI-441, AI-447): null_exclusion is illegal in Ada 95,
1014
            --  except in the case of anonymous access types.
1015
 
1016
            --  Allow_Anonymous_In_95 will be True if we're parsing a formal
1017
            --  parameter or discriminant, which are the only places where
1018
            --  anonymous access types occur in Ada 95. "Formal : not null
1019
            --  access ..." is legal in Ada 95, whereas "Formal : not null
1020
            --  Named_Access_Type" is not.
1021
 
1022
            if Ada_Version >= Ada_05
1023
              or else (Ada_Version >= Ada_95
1024
                        and then Allow_Anonymous_In_95
1025
                        and then Token = Tok_Access)
1026
            then
1027
               null; -- OK
1028
 
1029
            else
1030
               Error_Msg
1031
                 ("`NOT NULL` access type is an Ada 2005 extension", Not_Loc);
1032
               Error_Msg
1033
                 ("\unit should be compiled with -gnat05 switch", Not_Loc);
1034
            end if;
1035
 
1036
         else
1037
            Error_Msg_SP ("NULL expected");
1038
         end if;
1039
 
1040
         if Token = Tok_New then
1041
            Error_Msg ("`NOT NULL` comes after NEW, not before", Not_Loc);
1042
         end if;
1043
 
1044
         return True;
1045
      end if;
1046
   end P_Null_Exclusion;
1047
 
1048
   function P_Subtype_Indication
1049
     (Not_Null_Present : Boolean := False) return Node_Id
1050
   is
1051
      Type_Node : Node_Id;
1052
 
1053
   begin
1054
      if Token = Tok_Identifier or else Token = Tok_Operator_Symbol then
1055
         Type_Node := P_Subtype_Mark;
1056
         return P_Subtype_Indication (Type_Node, Not_Null_Present);
1057
 
1058
      else
1059
         --  Check for error of using record definition and treat it nicely,
1060
         --  otherwise things are really messed up, so resynchronize.
1061
 
1062
         if Token = Tok_Record then
1063
            Error_Msg_SC ("anonymous record definitions are not permitted");
1064
            Discard_Junk_Node (P_Record_Definition);
1065
            return Error;
1066
 
1067
         else
1068
            Error_Msg_AP ("subtype indication expected");
1069
            raise Error_Resync;
1070
         end if;
1071
      end if;
1072
   end P_Subtype_Indication;
1073
 
1074
   --  The following function is identical except that it is called with
1075
   --  the subtype mark already scanned out, and it scans out the constraint
1076
 
1077
   --  Error recovery: can raise Error_Resync
1078
 
1079
   function P_Subtype_Indication
1080
     (Subtype_Mark     : Node_Id;
1081
      Not_Null_Present : Boolean := False) return Node_Id
1082
   is
1083
      Indic_Node  : Node_Id;
1084
      Constr_Node : Node_Id;
1085
 
1086
   begin
1087
      Constr_Node := P_Constraint_Opt;
1088
 
1089
      if No (Constr_Node) then
1090
         return Subtype_Mark;
1091
      else
1092
         if Not_Null_Present then
1093
            Error_Msg_SP ("`NOT NULL` not allowed if constraint given");
1094
         end if;
1095
 
1096
         Indic_Node := New_Node (N_Subtype_Indication, Sloc (Subtype_Mark));
1097
         Set_Subtype_Mark (Indic_Node, Check_Subtype_Mark (Subtype_Mark));
1098
         Set_Constraint (Indic_Node, Constr_Node);
1099
         return Indic_Node;
1100
      end if;
1101
   end P_Subtype_Indication;
1102
 
1103
   -------------------------
1104
   -- 3.2.2  Subtype Mark --
1105
   -------------------------
1106
 
1107
   --  SUBTYPE_MARK ::= subtype_NAME;
1108
 
1109
   --  Note: The subtype mark which appears after an IN or NOT IN
1110
   --  operator is parsed by P_Range_Or_Subtype_Mark (3.5)
1111
 
1112
   --  Error recovery: cannot raise Error_Resync
1113
 
1114
   function P_Subtype_Mark return Node_Id is
1115
   begin
1116
      return P_Subtype_Mark_Resync;
1117
   exception
1118
      when Error_Resync =>
1119
         return Error;
1120
   end P_Subtype_Mark;
1121
 
1122
   --  This routine differs from P_Subtype_Mark in that it insists that an
1123
   --  identifier be present, and if it is not, it raises Error_Resync.
1124
 
1125
   --  Error recovery: can raise Error_Resync
1126
 
1127
   function P_Subtype_Mark_Resync return Node_Id is
1128
      Type_Node : Node_Id;
1129
 
1130
   begin
1131
      if Token = Tok_Access then
1132
         Error_Msg_SC ("anonymous access type definition not allowed here");
1133
         Scan; -- past ACCESS
1134
      end if;
1135
 
1136
      if Token = Tok_Array then
1137
         Error_Msg_SC ("anonymous array definition not allowed here");
1138
         Discard_Junk_Node (P_Array_Type_Definition);
1139
         return Error;
1140
 
1141
      else
1142
         Type_Node := P_Qualified_Simple_Name_Resync;
1143
 
1144
         --  Check for a subtype mark attribute. The only valid possibilities
1145
         --  are 'CLASS and 'BASE. Anything else is a definite error. We may
1146
         --  as well catch it here.
1147
 
1148
         if Token = Tok_Apostrophe then
1149
            return P_Subtype_Mark_Attribute (Type_Node);
1150
         else
1151
            return Type_Node;
1152
         end if;
1153
      end if;
1154
   end P_Subtype_Mark_Resync;
1155
 
1156
   --  The following function is called to scan out a subtype mark attribute.
1157
   --  The caller has already scanned out the subtype mark, which is passed in
1158
   --  as the argument, and has checked that the current token is apostrophe.
1159
 
1160
   --  Only a special subclass of attributes, called type attributes
1161
   --  (see Snames package) are allowed in this syntactic position.
1162
 
1163
   --  Note: if the apostrophe is followed by other than an identifier, then
1164
   --  the input expression is returned unchanged, and the scan pointer is
1165
   --  left pointing to the apostrophe.
1166
 
1167
   --  Error recovery: can raise Error_Resync
1168
 
1169
   function P_Subtype_Mark_Attribute (Type_Node : Node_Id) return Node_Id is
1170
      Attr_Node  : Node_Id := Empty;
1171
      Scan_State : Saved_Scan_State;
1172
      Prefix     : Node_Id;
1173
 
1174
   begin
1175
      Prefix := Check_Subtype_Mark (Type_Node);
1176
 
1177
      if Prefix = Error then
1178
         raise Error_Resync;
1179
      end if;
1180
 
1181
      --  Loop through attributes appearing (more than one can appear as for
1182
      --  for example in X'Base'Class). We are at an apostrophe on entry to
1183
      --  this loop, and it runs once for each attribute parsed, with
1184
      --  Prefix being the current possible prefix if it is an attribute.
1185
 
1186
      loop
1187
         Save_Scan_State (Scan_State); -- at Apostrophe
1188
         Scan; -- past apostrophe
1189
 
1190
         if Token /= Tok_Identifier then
1191
            Restore_Scan_State (Scan_State); -- to apostrophe
1192
            return Prefix; -- no attribute after all
1193
 
1194
         elsif not Is_Type_Attribute_Name (Token_Name) then
1195
            Error_Msg_N
1196
              ("attribute & may not be used in a subtype mark", Token_Node);
1197
            raise Error_Resync;
1198
 
1199
         else
1200
            Attr_Node :=
1201
              Make_Attribute_Reference (Prev_Token_Ptr,
1202
                Prefix => Prefix,
1203
                Attribute_Name => Token_Name);
1204
            Scan; -- past type attribute identifier
1205
         end if;
1206
 
1207
         exit when Token /= Tok_Apostrophe;
1208
         Prefix := Attr_Node;
1209
      end loop;
1210
 
1211
      --  Fall through here after scanning type attribute
1212
 
1213
      return Attr_Node;
1214
   end P_Subtype_Mark_Attribute;
1215
 
1216
   -----------------------
1217
   -- 3.2.2  Constraint --
1218
   -----------------------
1219
 
1220
   --  CONSTRAINT ::= SCALAR_CONSTRAINT | COMPOSITE_CONSTRAINT
1221
 
1222
   --  SCALAR_CONSTRAINT ::=
1223
   --    RANGE_CONSTRAINT | DIGITS_CONSTRAINT | DELTA_CONSTRAINT
1224
 
1225
   --  COMPOSITE_CONSTRAINT ::=
1226
   --    INDEX_CONSTRAINT | DISCRIMINANT_CONSTRAINT
1227
 
1228
   --  If no constraint is present, this function returns Empty
1229
 
1230
   --  Error recovery: can raise Error_Resync
1231
 
1232
   function P_Constraint_Opt return Node_Id is
1233
   begin
1234
      if Token = Tok_Range
1235
        or else Bad_Spelling_Of (Tok_Range)
1236
      then
1237
         return P_Range_Constraint;
1238
 
1239
      elsif Token = Tok_Digits
1240
        or else Bad_Spelling_Of (Tok_Digits)
1241
      then
1242
         return P_Digits_Constraint;
1243
 
1244
      elsif Token = Tok_Delta
1245
        or else Bad_Spelling_Of (Tok_Delta)
1246
      then
1247
         return P_Delta_Constraint;
1248
 
1249
      elsif Token = Tok_Left_Paren then
1250
         return P_Index_Or_Discriminant_Constraint;
1251
 
1252
      elsif Token = Tok_In then
1253
         Ignore (Tok_In);
1254
         return P_Constraint_Opt;
1255
 
1256
      else
1257
         return Empty;
1258
      end if;
1259
   end P_Constraint_Opt;
1260
 
1261
   ------------------------------
1262
   -- 3.2.2  Scalar Constraint --
1263
   ------------------------------
1264
 
1265
   --  Parsed by P_Constraint_Opt (3.2.2)
1266
 
1267
   ---------------------------------
1268
   -- 3.2.2  Composite Constraint --
1269
   ---------------------------------
1270
 
1271
   --  Parsed by P_Constraint_Opt (3.2.2)
1272
 
1273
   --------------------------------------------------------
1274
   -- 3.3  Identifier Declarations (Also 7.4, 8.5, 11.1) --
1275
   --------------------------------------------------------
1276
 
1277
   --  This routine scans out a declaration starting with an identifier:
1278
 
1279
   --  OBJECT_DECLARATION ::=
1280
   --    DEFINING_IDENTIFIER_LIST : [aliased] [constant]
1281
   --      [NULL_EXCLUSION] SUBTYPE_INDICATION [:= EXPRESSION];
1282
   --  | DEFINING_IDENTIFIER_LIST : [aliased] [constant]
1283
   --      ACCESS_DEFINITION [:= EXPRESSION];
1284
   --  | DEFINING_IDENTIFIER_LIST : [aliased] [constant]
1285
   --      ARRAY_TYPE_DEFINITION [:= EXPRESSION];
1286
 
1287
   --  NUMBER_DECLARATION ::=
1288
   --    DEFINING_IDENTIFIER_LIST : constant ::= static_EXPRESSION;
1289
 
1290
   --  OBJECT_RENAMING_DECLARATION ::=
1291
   --    DEFINING_IDENTIFIER :
1292
   --      [NULL_EXCLUSION] SUBTYPE_MARK renames object_NAME;
1293
   --  | DEFINING_IDENTIFIER :
1294
   --      ACCESS_DEFINITION renames object_NAME;
1295
 
1296
   --  EXCEPTION_RENAMING_DECLARATION ::=
1297
   --    DEFINING_IDENTIFIER : exception renames exception_NAME;
1298
 
1299
   --  EXCEPTION_DECLARATION ::=
1300
   --    DEFINING_IDENTIFIER_LIST : exception;
1301
 
1302
   --  Note that the ALIASED indication in an object declaration is
1303
   --  marked by a flag in the parent node.
1304
 
1305
   --  The caller has checked that the initial token is an identifier
1306
 
1307
   --  The value returned is a list of declarations, one for each identifier
1308
   --  in the list (as described in Sinfo, we always split up multiple
1309
   --  declarations into the equivalent sequence of single declarations
1310
   --  using the More_Ids and Prev_Ids flags to preserve the source).
1311
 
1312
   --  If the identifier turns out to be a probable statement rather than
1313
   --  an identifier, then the scan is left pointing to the identifier and
1314
   --  No_List is returned.
1315
 
1316
   --  Error recovery: can raise Error_Resync
1317
 
1318
   procedure P_Identifier_Declarations
1319
     (Decls   : List_Id;
1320
      Done    : out Boolean;
1321
      In_Spec : Boolean)
1322
   is
1323
      Acc_Node         : Node_Id;
1324
      Decl_Node        : Node_Id;
1325
      Type_Node        : Node_Id;
1326
      Ident_Sloc       : Source_Ptr;
1327
      Scan_State       : Saved_Scan_State;
1328
      List_OK          : Boolean := True;
1329
      Ident            : Nat;
1330
      Init_Expr        : Node_Id;
1331
      Init_Loc         : Source_Ptr;
1332
      Con_Loc          : Source_Ptr;
1333
      Not_Null_Present : Boolean := False;
1334
 
1335
      Idents : array (Int range 1 .. 4096) of Entity_Id;
1336
      --  Used to save identifiers in the identifier list. The upper bound
1337
      --  of 4096 is expected to be infinite in practice, and we do not even
1338
      --  bother to check if this upper bound is exceeded.
1339
 
1340
      Num_Idents : Nat := 1;
1341
      --  Number of identifiers stored in Idents
1342
 
1343
      procedure No_List;
1344
      --  This procedure is called in renames cases to make sure that we do
1345
      --  not have more than one identifier. If we do have more than one
1346
      --  then an error message is issued (and the declaration is split into
1347
      --  multiple declarations)
1348
 
1349
      function Token_Is_Renames return Boolean;
1350
      --  Checks if current token is RENAMES, and if so, scans past it and
1351
      --  returns True, otherwise returns False. Includes checking for some
1352
      --  common error cases.
1353
 
1354
      -------------
1355
      -- No_List --
1356
      -------------
1357
 
1358
      procedure No_List is
1359
      begin
1360
         if Num_Idents > 1 then
1361
            Error_Msg ("identifier list not allowed for RENAMES",
1362
                       Sloc (Idents (2)));
1363
         end if;
1364
 
1365
         List_OK := False;
1366
      end No_List;
1367
 
1368
      ----------------------
1369
      -- Token_Is_Renames --
1370
      ----------------------
1371
 
1372
      function Token_Is_Renames return Boolean is
1373
         At_Colon : Saved_Scan_State;
1374
 
1375
      begin
1376
         if Token = Tok_Colon then
1377
            Save_Scan_State (At_Colon);
1378
            Scan; -- past colon
1379
            Check_Misspelling_Of (Tok_Renames);
1380
 
1381
            if Token = Tok_Renames then
1382
               Error_Msg_SP ("|extra "":"" ignored");
1383
               Scan; -- past RENAMES
1384
               return True;
1385
            else
1386
               Restore_Scan_State (At_Colon);
1387
               return False;
1388
            end if;
1389
 
1390
         else
1391
            Check_Misspelling_Of (Tok_Renames);
1392
 
1393
            if Token = Tok_Renames then
1394
               Scan; -- past RENAMES
1395
               return True;
1396
            else
1397
               return False;
1398
            end if;
1399
         end if;
1400
      end Token_Is_Renames;
1401
 
1402
   --  Start of processing for P_Identifier_Declarations
1403
 
1404
   begin
1405
      Ident_Sloc := Token_Ptr;
1406
      Save_Scan_State (Scan_State); -- at first identifier
1407
      Idents (1) := P_Defining_Identifier (C_Comma_Colon);
1408
 
1409
      --  If we have a colon after the identifier, then we can assume that
1410
      --  this is in fact a valid identifier declaration and can steam ahead.
1411
 
1412
      if Token = Tok_Colon then
1413
         Scan; -- past colon
1414
 
1415
      --  If we have a comma, then scan out the list of identifiers
1416
 
1417
      elsif Token = Tok_Comma then
1418
         while Comma_Present loop
1419
            Num_Idents := Num_Idents + 1;
1420
            Idents (Num_Idents) := P_Defining_Identifier (C_Comma_Colon);
1421
         end loop;
1422
 
1423
         Save_Scan_State (Scan_State); -- at colon
1424
         T_Colon;
1425
 
1426
      --  If we have identifier followed by := then we assume that what is
1427
      --  really meant is an assignment statement. The assignment statement
1428
      --  is scanned out and added to the list of declarations. An exception
1429
      --  occurs if the := is followed by the keyword constant, in which case
1430
      --  we assume it was meant to be a colon.
1431
 
1432
      elsif Token = Tok_Colon_Equal then
1433
         Scan; -- past :=
1434
 
1435
         if Token = Tok_Constant then
1436
            Error_Msg_SP ("colon expected");
1437
 
1438
         else
1439
            Restore_Scan_State (Scan_State);
1440
            Statement_When_Declaration_Expected (Decls, Done, In_Spec);
1441
            return;
1442
         end if;
1443
 
1444
      --  If we have an IS keyword, then assume the TYPE keyword was missing
1445
 
1446
      elsif Token = Tok_Is then
1447
         Restore_Scan_State (Scan_State);
1448
         Append_To (Decls, P_Type_Declaration);
1449
         Done := False;
1450
         return;
1451
 
1452
      --  Otherwise we have an error situation
1453
 
1454
      else
1455
         Restore_Scan_State (Scan_State);
1456
 
1457
         --  First case is possible misuse of PROTECTED in Ada 83 mode. If
1458
         --  so, fix the keyword and return to scan the protected declaration.
1459
 
1460
         if Token_Name = Name_Protected then
1461
            Check_95_Keyword (Tok_Protected, Tok_Identifier);
1462
            Check_95_Keyword (Tok_Protected, Tok_Type);
1463
            Check_95_Keyword (Tok_Protected, Tok_Body);
1464
 
1465
            if Token = Tok_Protected then
1466
               Done := False;
1467
               return;
1468
            end if;
1469
 
1470
         --  Check misspelling possibilities. If so, correct the misspelling
1471
         --  and return to scan out the resulting declaration.
1472
 
1473
         elsif Bad_Spelling_Of (Tok_Function)
1474
           or else Bad_Spelling_Of (Tok_Procedure)
1475
           or else Bad_Spelling_Of (Tok_Package)
1476
           or else Bad_Spelling_Of (Tok_Pragma)
1477
           or else Bad_Spelling_Of (Tok_Protected)
1478
           or else Bad_Spelling_Of (Tok_Generic)
1479
           or else Bad_Spelling_Of (Tok_Subtype)
1480
           or else Bad_Spelling_Of (Tok_Type)
1481
           or else Bad_Spelling_Of (Tok_Task)
1482
           or else Bad_Spelling_Of (Tok_Use)
1483
           or else Bad_Spelling_Of (Tok_For)
1484
         then
1485
            Done := False;
1486
            return;
1487
 
1488
         --  Otherwise we definitely have an ordinary identifier with a junk
1489
         --  token after it. Just complain that we expect a declaration, and
1490
         --  skip to a semicolon
1491
 
1492
         else
1493
            Set_Declaration_Expected;
1494
            Resync_Past_Semicolon;
1495
            Done := False;
1496
            return;
1497
         end if;
1498
      end if;
1499
 
1500
      --  Come here with an identifier list and colon scanned out. We now
1501
      --  build the nodes for the declarative items. One node is built for
1502
      --  each identifier in the list, with the type information being
1503
      --  repeated by rescanning the appropriate section of source.
1504
 
1505
      --  First an error check, if we have two identifiers in a row, a likely
1506
      --  possibility is that the first of the identifiers is an incorrectly
1507
      --  spelled keyword.
1508
 
1509
      if Token = Tok_Identifier then
1510
         declare
1511
            SS : Saved_Scan_State;
1512
            I2 : Boolean;
1513
 
1514
         begin
1515
            Save_Scan_State (SS);
1516
            Scan; -- past initial identifier
1517
            I2 := (Token = Tok_Identifier);
1518
            Restore_Scan_State (SS);
1519
 
1520
            if I2
1521
              and then
1522
                (Bad_Spelling_Of (Tok_Access)   or else
1523
                 Bad_Spelling_Of (Tok_Aliased)  or else
1524
                 Bad_Spelling_Of (Tok_Constant))
1525
            then
1526
               null;
1527
            end if;
1528
         end;
1529
      end if;
1530
 
1531
      --  Loop through identifiers
1532
 
1533
      Ident := 1;
1534
      Ident_Loop : loop
1535
 
1536
         --  Check for some cases of misused Ada 95 keywords
1537
 
1538
         if Token_Name = Name_Aliased then
1539
            Check_95_Keyword (Tok_Aliased, Tok_Array);
1540
            Check_95_Keyword (Tok_Aliased, Tok_Identifier);
1541
            Check_95_Keyword (Tok_Aliased, Tok_Constant);
1542
         end if;
1543
 
1544
         --  Constant cases
1545
 
1546
         if Token = Tok_Constant then
1547
            Con_Loc := Token_Ptr;
1548
            Scan; -- past CONSTANT
1549
 
1550
            --  Number declaration, initialization required
1551
 
1552
            Init_Expr := Init_Expr_Opt;
1553
 
1554
            if Present (Init_Expr) then
1555
               if Not_Null_Present then
1556
                  Error_Msg_SP
1557
                    ("`NOT NULL` not allowed in numeric expression");
1558
               end if;
1559
 
1560
               Decl_Node := New_Node (N_Number_Declaration, Ident_Sloc);
1561
               Set_Expression (Decl_Node, Init_Expr);
1562
 
1563
            --  Constant object declaration
1564
 
1565
            else
1566
               Decl_Node := New_Node (N_Object_Declaration, Ident_Sloc);
1567
               Set_Constant_Present (Decl_Node, True);
1568
 
1569
               if Token_Name = Name_Aliased then
1570
                  Check_95_Keyword (Tok_Aliased, Tok_Array);
1571
                  Check_95_Keyword (Tok_Aliased, Tok_Identifier);
1572
               end if;
1573
 
1574
               if Token = Tok_Aliased then
1575
                  Error_Msg_SC -- CODEFIX
1576
                    ("ALIASED should be before CONSTANT");
1577
                  Scan; -- past ALIASED
1578
                  Set_Aliased_Present (Decl_Node, True);
1579
               end if;
1580
 
1581
               if Token = Tok_Array then
1582
                  Set_Object_Definition
1583
                    (Decl_Node, P_Array_Type_Definition);
1584
 
1585
               else
1586
                  Not_Null_Present := P_Null_Exclusion; --  Ada 2005 (AI-231)
1587
                  Set_Null_Exclusion_Present (Decl_Node, Not_Null_Present);
1588
 
1589
                  if Token = Tok_Access then
1590
                     if Ada_Version < Ada_05 then
1591
                        Error_Msg_SP
1592
                          ("generalized use of anonymous access types " &
1593
                           "is an Ada 2005 extension");
1594
                        Error_Msg_SP
1595
                          ("\unit must be compiled with -gnat05 switch");
1596
                     end if;
1597
 
1598
                     Set_Object_Definition
1599
                       (Decl_Node, P_Access_Definition (Not_Null_Present));
1600
                  else
1601
                     Set_Object_Definition
1602
                       (Decl_Node, P_Subtype_Indication (Not_Null_Present));
1603
                  end if;
1604
               end if;
1605
 
1606
               if Token = Tok_Renames then
1607
                  Error_Msg
1608
                    ("CONSTANT not permitted in renaming declaration",
1609
                     Con_Loc);
1610
                  Scan; -- Past renames
1611
                  Discard_Junk_Node (P_Name);
1612
               end if;
1613
            end if;
1614
 
1615
         --  Exception cases
1616
 
1617
         elsif Token = Tok_Exception then
1618
            Scan; -- past EXCEPTION
1619
 
1620
            if Token_Is_Renames then
1621
               No_List;
1622
               Decl_Node :=
1623
                 New_Node (N_Exception_Renaming_Declaration, Ident_Sloc);
1624
               Set_Name (Decl_Node, P_Qualified_Simple_Name_Resync);
1625
               No_Constraint;
1626
            else
1627
               Decl_Node := New_Node (N_Exception_Declaration, Prev_Token_Ptr);
1628
            end if;
1629
 
1630
         --  Aliased case (note that an object definition is required)
1631
 
1632
         elsif Token = Tok_Aliased then
1633
            Scan; -- past ALIASED
1634
            Decl_Node := New_Node (N_Object_Declaration, Ident_Sloc);
1635
            Set_Aliased_Present (Decl_Node, True);
1636
 
1637
            if Token = Tok_Constant then
1638
               Scan; -- past CONSTANT
1639
               Set_Constant_Present (Decl_Node, True);
1640
            end if;
1641
 
1642
            if Token = Tok_Array then
1643
               Set_Object_Definition
1644
                 (Decl_Node, P_Array_Type_Definition);
1645
 
1646
            else
1647
               Not_Null_Present := P_Null_Exclusion; --  Ada 2005 (AI-231)
1648
               Set_Null_Exclusion_Present (Decl_Node, Not_Null_Present);
1649
 
1650
               --  Access definition (AI-406) or subtype indication
1651
 
1652
               if Token = Tok_Access then
1653
                  if Ada_Version < Ada_05 then
1654
                     Error_Msg_SP
1655
                       ("generalized use of anonymous access types " &
1656
                        "is an Ada 2005 extension");
1657
                     Error_Msg_SP
1658
                       ("\unit must be compiled with -gnat05 switch");
1659
                  end if;
1660
 
1661
                  Set_Object_Definition
1662
                    (Decl_Node, P_Access_Definition (Not_Null_Present));
1663
               else
1664
                  Set_Object_Definition
1665
                    (Decl_Node, P_Subtype_Indication (Not_Null_Present));
1666
               end if;
1667
            end if;
1668
 
1669
         --  Array case
1670
 
1671
         elsif Token = Tok_Array then
1672
            Decl_Node := New_Node (N_Object_Declaration, Ident_Sloc);
1673
            Set_Object_Definition (Decl_Node, P_Array_Type_Definition);
1674
 
1675
         --  Ada 2005 (AI-254, AI-406)
1676
 
1677
         elsif Token = Tok_Not then
1678
 
1679
            --  OBJECT_DECLARATION ::=
1680
            --    DEFINING_IDENTIFIER_LIST : [aliased] [constant]
1681
            --      [NULL_EXCLUSION] SUBTYPE_INDICATION [:= EXPRESSION];
1682
            --  | DEFINING_IDENTIFIER_LIST : [aliased] [constant]
1683
            --      ACCESS_DEFINITION [:= EXPRESSION];
1684
 
1685
            --  OBJECT_RENAMING_DECLARATION ::=
1686
            --    DEFINING_IDENTIFIER :
1687
            --      [NULL_EXCLUSION] SUBTYPE_MARK renames object_NAME;
1688
            --  | DEFINING_IDENTIFIER :
1689
            --      ACCESS_DEFINITION renames object_NAME;
1690
 
1691
            Not_Null_Present := P_Null_Exclusion;  --  Ada 2005 (AI-231/423)
1692
 
1693
            if Token = Tok_Access then
1694
               if Ada_Version < Ada_05 then
1695
                  Error_Msg_SP
1696
                    ("generalized use of anonymous access types " &
1697
                     "is an Ada 2005 extension");
1698
                  Error_Msg_SP ("\unit must be compiled with -gnat05 switch");
1699
               end if;
1700
 
1701
               Acc_Node := P_Access_Definition (Not_Null_Present);
1702
 
1703
               if Token /= Tok_Renames then
1704
                  Decl_Node := New_Node (N_Object_Declaration, Ident_Sloc);
1705
                  Set_Object_Definition (Decl_Node, Acc_Node);
1706
 
1707
               else
1708
                  Scan; --  past renames
1709
                  No_List;
1710
                  Decl_Node :=
1711
                    New_Node (N_Object_Renaming_Declaration, Ident_Sloc);
1712
                  Set_Access_Definition (Decl_Node, Acc_Node);
1713
                  Set_Name (Decl_Node, P_Name);
1714
               end if;
1715
 
1716
            else
1717
               Type_Node := P_Subtype_Mark;
1718
 
1719
               --  Object renaming declaration
1720
 
1721
               if Token_Is_Renames then
1722
                  if Ada_Version < Ada_05 then
1723
                     Error_Msg_SP
1724
                       ("`NOT NULL` not allowed in object renaming");
1725
                     raise Error_Resync;
1726
 
1727
                  --  Ada 2005 (AI-423): Object renaming declaration with
1728
                  --  a null exclusion.
1729
 
1730
                  else
1731
                     No_List;
1732
                     Decl_Node :=
1733
                       New_Node (N_Object_Renaming_Declaration, Ident_Sloc);
1734
                     Set_Null_Exclusion_Present (Decl_Node, Not_Null_Present);
1735
                     Set_Subtype_Mark (Decl_Node, Type_Node);
1736
                     Set_Name (Decl_Node, P_Name);
1737
                  end if;
1738
 
1739
               --  Object declaration
1740
 
1741
               else
1742
                  Decl_Node := New_Node (N_Object_Declaration, Ident_Sloc);
1743
                  Set_Null_Exclusion_Present (Decl_Node, Not_Null_Present);
1744
                  Set_Object_Definition
1745
                    (Decl_Node,
1746
                     P_Subtype_Indication (Type_Node, Not_Null_Present));
1747
 
1748
                  --  RENAMES at this point means that we had the combination
1749
                  --  of a constraint on the Type_Node and renames, which is
1750
                  --  illegal
1751
 
1752
                  if Token_Is_Renames then
1753
                     Error_Msg_N ("constraint not allowed in object renaming "
1754
                                  & "declaration",
1755
                                  Constraint (Object_Definition (Decl_Node)));
1756
                     raise Error_Resync;
1757
                  end if;
1758
               end if;
1759
            end if;
1760
 
1761
         --  Ada 2005 (AI-230): Access Definition case
1762
 
1763
         elsif Token = Tok_Access then
1764
            if Ada_Version < Ada_05 then
1765
               Error_Msg_SP
1766
                 ("generalized use of anonymous access types " &
1767
                  "is an Ada 2005 extension");
1768
               Error_Msg_SP ("\unit must be compiled with -gnat05 switch");
1769
            end if;
1770
 
1771
            Acc_Node := P_Access_Definition (Null_Exclusion_Present => False);
1772
 
1773
            --  Object declaration with access definition, or renaming
1774
 
1775
            if Token /= Tok_Renames then
1776
               Decl_Node := New_Node (N_Object_Declaration, Ident_Sloc);
1777
               Set_Object_Definition (Decl_Node, Acc_Node);
1778
 
1779
            else
1780
               Scan; --  past renames
1781
               No_List;
1782
               Decl_Node :=
1783
                 New_Node (N_Object_Renaming_Declaration, Ident_Sloc);
1784
               Set_Access_Definition (Decl_Node, Acc_Node);
1785
               Set_Name (Decl_Node, P_Name);
1786
            end if;
1787
 
1788
         --  Subtype indication case
1789
 
1790
         else
1791
            Type_Node := P_Subtype_Mark;
1792
 
1793
            --  Object renaming declaration
1794
 
1795
            if Token_Is_Renames then
1796
               No_List;
1797
               Decl_Node :=
1798
                 New_Node (N_Object_Renaming_Declaration, Ident_Sloc);
1799
               Set_Subtype_Mark (Decl_Node, Type_Node);
1800
               Set_Name (Decl_Node, P_Name);
1801
 
1802
            --  Object declaration
1803
 
1804
            else
1805
               Decl_Node := New_Node (N_Object_Declaration, Ident_Sloc);
1806
               Set_Null_Exclusion_Present (Decl_Node, Not_Null_Present);
1807
               Set_Object_Definition
1808
                 (Decl_Node,
1809
                  P_Subtype_Indication (Type_Node, Not_Null_Present));
1810
 
1811
               --  RENAMES at this point means that we had the combination of
1812
               --  a constraint on the Type_Node and renames, which is illegal
1813
 
1814
               if Token_Is_Renames then
1815
                  Error_Msg_N
1816
                    ("constraint not allowed in object renaming declaration",
1817
                     Constraint (Object_Definition (Decl_Node)));
1818
                  raise Error_Resync;
1819
               end if;
1820
            end if;
1821
         end if;
1822
 
1823
         --  Scan out initialization, allowed only for object declaration
1824
 
1825
         Init_Loc := Token_Ptr;
1826
         Init_Expr := Init_Expr_Opt;
1827
 
1828
         if Present (Init_Expr) then
1829
            if Nkind (Decl_Node) = N_Object_Declaration then
1830
               Set_Expression (Decl_Node, Init_Expr);
1831
               Set_Has_Init_Expression (Decl_Node);
1832
            else
1833
               Error_Msg ("initialization not allowed here", Init_Loc);
1834
            end if;
1835
         end if;
1836
 
1837
         TF_Semicolon;
1838
         Set_Defining_Identifier (Decl_Node, Idents (Ident));
1839
 
1840
         if List_OK then
1841
            if Ident < Num_Idents then
1842
               Set_More_Ids (Decl_Node, True);
1843
            end if;
1844
 
1845
            if Ident > 1 then
1846
               Set_Prev_Ids (Decl_Node, True);
1847
            end if;
1848
         end if;
1849
 
1850
         Append (Decl_Node, Decls);
1851
         exit Ident_Loop when Ident = Num_Idents;
1852
         Restore_Scan_State (Scan_State);
1853
         T_Colon;
1854
         Ident := Ident + 1;
1855
      end loop Ident_Loop;
1856
 
1857
      Done := False;
1858
   end P_Identifier_Declarations;
1859
 
1860
   -------------------------------
1861
   -- 3.3.1  Object Declaration --
1862
   -------------------------------
1863
 
1864
   --  OBJECT DECLARATION ::=
1865
   --    DEFINING_IDENTIFIER_LIST : [aliased] [constant]
1866
   --      SUBTYPE_INDICATION [:= EXPRESSION];
1867
   --  | DEFINING_IDENTIFIER_LIST : [aliased] [constant]
1868
   --      ARRAY_TYPE_DEFINITION [:= EXPRESSION];
1869
   --  | SINGLE_TASK_DECLARATION
1870
   --  | SINGLE_PROTECTED_DECLARATION
1871
 
1872
   --  Cases starting with TASK are parsed by P_Task (9.1)
1873
   --  Cases starting with PROTECTED are parsed by P_Protected (9.4)
1874
   --  All other cases are parsed by P_Identifier_Declarations (3.3)
1875
 
1876
   -------------------------------------
1877
   -- 3.3.1  Defining Identifier List --
1878
   -------------------------------------
1879
 
1880
   --  DEFINING_IDENTIFIER_LIST ::=
1881
   --    DEFINING_IDENTIFIER {, DEFINING_IDENTIFIER}
1882
 
1883
   --  Always parsed by the construct in which it appears. See special
1884
   --  section on "Handling of Defining Identifier Lists" in this unit.
1885
 
1886
   -------------------------------
1887
   -- 3.3.2  Number Declaration --
1888
   -------------------------------
1889
 
1890
   --  Parsed by P_Identifier_Declarations (3.3)
1891
 
1892
   -------------------------------------------------------------------------
1893
   -- 3.4  Derived Type Definition or Private Extension Declaration (7.3) --
1894
   -------------------------------------------------------------------------
1895
 
1896
   --  DERIVED_TYPE_DEFINITION ::=
1897
   --    [abstract] [limited] new [NULL_EXCLUSION] parent_SUBTYPE_INDICATION
1898
   --    [[and INTERFACE_LIST] RECORD_EXTENSION_PART]
1899
 
1900
   --  PRIVATE_EXTENSION_DECLARATION ::=
1901
   --     type DEFINING_IDENTIFIER [DISCRIMINANT_PART] is
1902
   --       [abstract] [limited | synchronized]
1903
   --          new ancestor_SUBTYPE_INDICATION [and INTERFACE_LIST]
1904
   --            with private;
1905
 
1906
   --  RECORD_EXTENSION_PART ::= with RECORD_DEFINITION
1907
 
1908
   --  The caller has already scanned out the part up to the NEW, and Token
1909
   --  either contains Tok_New (or ought to, if it doesn't this procedure
1910
   --  will post an appropriate "NEW expected" message).
1911
 
1912
   --  Note: the caller is responsible for filling in the Sloc field of
1913
   --  the returned node in the private extension declaration case as
1914
   --  well as the stuff relating to the discriminant part.
1915
 
1916
   --  Error recovery: can raise Error_Resync;
1917
 
1918
   function P_Derived_Type_Def_Or_Private_Ext_Decl return Node_Id is
1919
      Typedef_Node     : Node_Id;
1920
      Typedecl_Node    : Node_Id;
1921
      Not_Null_Present : Boolean := False;
1922
 
1923
   begin
1924
      Typedef_Node := New_Node (N_Derived_Type_Definition, Token_Ptr);
1925
 
1926
      if Ada_Version < Ada_05
1927
        and then Token = Tok_Identifier
1928
        and then Token_Name = Name_Interface
1929
      then
1930
         Error_Msg_SP
1931
           ("abstract interface is an Ada 2005 extension");
1932
         Error_Msg_SP ("\unit must be compiled with -gnat05 switch");
1933
      else
1934
         T_New;
1935
      end if;
1936
 
1937
      if Token = Tok_Abstract then
1938
         Error_Msg_SC -- CODEFIX
1939
           ("ABSTRACT must come before NEW, not after");
1940
         Scan;
1941
      end if;
1942
 
1943
      Not_Null_Present := P_Null_Exclusion; --  Ada 2005 (AI-231)
1944
      Set_Null_Exclusion_Present (Typedef_Node, Not_Null_Present);
1945
      Set_Subtype_Indication (Typedef_Node,
1946
         P_Subtype_Indication (Not_Null_Present));
1947
 
1948
      --  Ada 2005 (AI-251): Deal with interfaces
1949
 
1950
      if Token = Tok_And then
1951
         Scan; -- past AND
1952
 
1953
         if Ada_Version < Ada_05 then
1954
            Error_Msg_SP
1955
              ("abstract interface is an Ada 2005 extension");
1956
            Error_Msg_SP ("\unit must be compiled with -gnat05 switch");
1957
         end if;
1958
 
1959
         Set_Interface_List (Typedef_Node, New_List);
1960
 
1961
         loop
1962
            Append (P_Qualified_Simple_Name, Interface_List (Typedef_Node));
1963
            exit when Token /= Tok_And;
1964
            Scan; -- past AND
1965
         end loop;
1966
 
1967
         if Token /= Tok_With then
1968
            Error_Msg_SC ("WITH expected");
1969
            raise Error_Resync;
1970
         end if;
1971
      end if;
1972
 
1973
      --  Deal with record extension, note that we assume that a WITH is
1974
      --  missing in the case of "type X is new Y record ..." or in the
1975
      --  case of "type X is new Y null record".
1976
 
1977
      if Token = Tok_With
1978
        or else Token = Tok_Record
1979
        or else Token = Tok_Null
1980
      then
1981
         T_With; -- past WITH or give error message
1982
 
1983
         if Token = Tok_Limited then
1984
            Error_Msg_SC
1985
              ("LIMITED keyword not allowed in private extension");
1986
            Scan; -- ignore LIMITED
1987
         end if;
1988
 
1989
         --  Private extension declaration
1990
 
1991
         if Token = Tok_Private then
1992
            Scan; -- past PRIVATE
1993
 
1994
            --  Throw away the type definition node and build the type
1995
            --  declaration node. Note the caller must set the Sloc,
1996
            --  Discriminant_Specifications, Unknown_Discriminants_Present,
1997
            --  and Defined_Identifier fields in the returned node.
1998
 
1999
            Typedecl_Node :=
2000
              Make_Private_Extension_Declaration (No_Location,
2001
                Defining_Identifier => Empty,
2002
                Subtype_Indication  => Subtype_Indication (Typedef_Node),
2003
                Abstract_Present    => Abstract_Present (Typedef_Node),
2004
                Interface_List      => Interface_List (Typedef_Node));
2005
 
2006
            return Typedecl_Node;
2007
 
2008
         --  Derived type definition with record extension part
2009
 
2010
         else
2011
            Set_Record_Extension_Part (Typedef_Node, P_Record_Definition);
2012
            return Typedef_Node;
2013
         end if;
2014
 
2015
      --  Derived type definition with no record extension part
2016
 
2017
      else
2018
         return Typedef_Node;
2019
      end if;
2020
   end P_Derived_Type_Def_Or_Private_Ext_Decl;
2021
 
2022
   ---------------------------
2023
   -- 3.5  Range Constraint --
2024
   ---------------------------
2025
 
2026
   --  RANGE_CONSTRAINT ::= range RANGE
2027
 
2028
   --  The caller has checked that the initial token is RANGE
2029
 
2030
   --  Error recovery: cannot raise Error_Resync
2031
 
2032
   function P_Range_Constraint return Node_Id is
2033
      Range_Node : Node_Id;
2034
 
2035
   begin
2036
      Range_Node := New_Node (N_Range_Constraint, Token_Ptr);
2037
      Scan; -- past RANGE
2038
      Set_Range_Expression (Range_Node, P_Range);
2039
      return Range_Node;
2040
   end P_Range_Constraint;
2041
 
2042
   ----------------
2043
   -- 3.5  Range --
2044
   ----------------
2045
 
2046
   --  RANGE ::=
2047
   --    RANGE_ATTRIBUTE_REFERENCE | SIMPLE_EXPRESSION .. SIMPLE_EXPRESSION
2048
 
2049
   --  Note: the range that appears in a membership test is parsed by
2050
   --  P_Range_Or_Subtype_Mark (3.5).
2051
 
2052
   --  Error recovery: cannot raise Error_Resync
2053
 
2054
   function P_Range return Node_Id is
2055
      Expr_Node  : Node_Id;
2056
      Range_Node : Node_Id;
2057
 
2058
   begin
2059
      Expr_Node := P_Simple_Expression_Or_Range_Attribute;
2060
 
2061
      if Expr_Form = EF_Range_Attr then
2062
         return Expr_Node;
2063
 
2064
      elsif Token = Tok_Dot_Dot then
2065
         Range_Node := New_Node (N_Range, Token_Ptr);
2066
         Set_Low_Bound (Range_Node, Expr_Node);
2067
         Scan; -- past ..
2068
         Expr_Node := P_Expression;
2069
         Check_Simple_Expression (Expr_Node);
2070
         Set_High_Bound (Range_Node, Expr_Node);
2071
         return Range_Node;
2072
 
2073
      --  Anything else is an error
2074
 
2075
      else
2076
         T_Dot_Dot; -- force missing .. message
2077
         return Error;
2078
      end if;
2079
   end P_Range;
2080
 
2081
   ----------------------------------
2082
   -- 3.5  P_Range_Or_Subtype_Mark --
2083
   ----------------------------------
2084
 
2085
   --  RANGE ::=
2086
   --    RANGE_ATTRIBUTE_REFERENCE
2087
   --  | SIMPLE_EXPRESSION .. SIMPLE_EXPRESSION
2088
 
2089
   --  This routine scans out the range or subtype mark that forms the right
2090
   --  operand of a membership test (it is not used in any other contexts, and
2091
   --  error messages are specialized with this knowledge in mind).
2092
 
2093
   --  Note: as documented in the Sinfo interface, although the syntax only
2094
   --  allows a subtype mark, we in fact allow any simple expression to be
2095
   --  returned from this routine. The semantics is responsible for issuing
2096
   --  an appropriate message complaining if the argument is not a name.
2097
   --  This simplifies the coding and error recovery processing in the
2098
   --  parser, and in any case it is preferable not to consider this a
2099
   --  syntax error and to continue with the semantic analysis.
2100
 
2101
   --  Error recovery: cannot raise Error_Resync
2102
 
2103
   function P_Range_Or_Subtype_Mark
2104
     (Allow_Simple_Expression : Boolean := False) return Node_Id
2105
   is
2106
      Expr_Node  : Node_Id;
2107
      Range_Node : Node_Id;
2108
      Save_Loc   : Source_Ptr;
2109
 
2110
 
2111
   --  Start of processing for P_Range_Or_Subtype_Mark
2112
 
2113
   begin
2114
      --  Save location of possible junk parentheses
2115
 
2116
      Save_Loc := Token_Ptr;
2117
 
2118
      --  Scan out either a simple expression or a range (this accepts more
2119
      --  than is legal here, but as explained above, we like to allow more
2120
      --  with a proper diagnostic, and in the case of a membership operation
2121
      --  where sets are allowed, a simple expression is permissible anyway.
2122
 
2123
      Expr_Node := P_Simple_Expression_Or_Range_Attribute;
2124
 
2125
      --  Range attribute
2126
 
2127
      if Expr_Form = EF_Range_Attr then
2128
         return Expr_Node;
2129
 
2130
      --  Simple_Expression .. Simple_Expression
2131
 
2132
      elsif Token = Tok_Dot_Dot then
2133
         Check_Simple_Expression (Expr_Node);
2134
         Range_Node := New_Node (N_Range, Token_Ptr);
2135
         Set_Low_Bound (Range_Node, Expr_Node);
2136
         Scan; -- past ..
2137
         Set_High_Bound (Range_Node, P_Simple_Expression);
2138
         return Range_Node;
2139
 
2140
      --  Case of subtype mark (optionally qualified simple name or an
2141
      --  attribute whose prefix is an optionally qualified simple name)
2142
 
2143
      elsif Expr_Form = EF_Simple_Name
2144
        or else Nkind (Expr_Node) = N_Attribute_Reference
2145
      then
2146
         --  Check for error of range constraint after a subtype mark
2147
 
2148
         if Token = Tok_Range then
2149
            Error_Msg_SC ("range constraint not allowed in membership test");
2150
            Scan; -- past RANGE
2151
            raise Error_Resync;
2152
 
2153
         --  Check for error of DIGITS or DELTA after a subtype mark
2154
 
2155
         elsif Token = Tok_Digits or else Token = Tok_Delta then
2156
            Error_Msg_SC
2157
              ("accuracy definition not allowed in membership test");
2158
            Scan; -- past DIGITS or DELTA
2159
            raise Error_Resync;
2160
 
2161
         --  Attribute reference, may or may not be OK, but in any case we
2162
         --  will scan it out
2163
 
2164
         elsif Token = Tok_Apostrophe then
2165
            return P_Subtype_Mark_Attribute (Expr_Node);
2166
 
2167
         --  OK case of simple name, just return it
2168
 
2169
         else
2170
            return Expr_Node;
2171
         end if;
2172
 
2173
      --  Here we have some kind of error situation. Check for junk parens
2174
      --  then return what we have, caller will deal with other errors.
2175
 
2176
      else
2177
         if Nkind (Expr_Node) in N_Subexpr
2178
           and then Paren_Count (Expr_Node) /= 0
2179
         then
2180
            Error_Msg ("|parentheses not allowed for subtype mark", Save_Loc);
2181
            Set_Paren_Count (Expr_Node, 0);
2182
         end if;
2183
 
2184
         return Expr_Node;
2185
      end if;
2186
   end P_Range_Or_Subtype_Mark;
2187
 
2188
   ----------------------------------------
2189
   -- 3.5.1  Enumeration Type Definition --
2190
   ----------------------------------------
2191
 
2192
   --  ENUMERATION_TYPE_DEFINITION ::=
2193
   --    (ENUMERATION_LITERAL_SPECIFICATION
2194
   --      {, ENUMERATION_LITERAL_SPECIFICATION})
2195
 
2196
   --  The caller has already scanned out the TYPE keyword
2197
 
2198
   --  Error recovery: can raise Error_Resync;
2199
 
2200
   function P_Enumeration_Type_Definition return Node_Id is
2201
      Typedef_Node : Node_Id;
2202
 
2203
   begin
2204
      Typedef_Node := New_Node (N_Enumeration_Type_Definition, Token_Ptr);
2205
      Set_Literals (Typedef_Node, New_List);
2206
 
2207
      T_Left_Paren;
2208
 
2209
      loop
2210
         Append (P_Enumeration_Literal_Specification, Literals (Typedef_Node));
2211
         exit when not Comma_Present;
2212
      end loop;
2213
 
2214
      T_Right_Paren;
2215
      return Typedef_Node;
2216
   end P_Enumeration_Type_Definition;
2217
 
2218
   ----------------------------------------------
2219
   -- 3.5.1  Enumeration Literal Specification --
2220
   ----------------------------------------------
2221
 
2222
   --  ENUMERATION_LITERAL_SPECIFICATION ::=
2223
   --    DEFINING_IDENTIFIER | DEFINING_CHARACTER_LITERAL
2224
 
2225
   --  Error recovery: can raise Error_Resync
2226
 
2227
   function P_Enumeration_Literal_Specification return Node_Id is
2228
   begin
2229
      if Token = Tok_Char_Literal then
2230
         return P_Defining_Character_Literal;
2231
      else
2232
         return P_Defining_Identifier (C_Comma_Right_Paren);
2233
      end if;
2234
   end P_Enumeration_Literal_Specification;
2235
 
2236
   ---------------------------------------
2237
   -- 3.5.1  Defining_Character_Literal --
2238
   ---------------------------------------
2239
 
2240
   --  DEFINING_CHARACTER_LITERAL ::= CHARACTER_LITERAL
2241
 
2242
   --  Error recovery: cannot raise Error_Resync
2243
 
2244
   --  The caller has checked that the current token is a character literal
2245
 
2246
   function P_Defining_Character_Literal return Node_Id is
2247
      Literal_Node : Node_Id;
2248
 
2249
   begin
2250
      Literal_Node := Token_Node;
2251
      Change_Character_Literal_To_Defining_Character_Literal (Literal_Node);
2252
      Scan; -- past character literal
2253
      return Literal_Node;
2254
   end P_Defining_Character_Literal;
2255
 
2256
   ------------------------------------
2257
   -- 3.5.4  Integer Type Definition --
2258
   ------------------------------------
2259
 
2260
   --  Parsed by P_Type_Declaration (3.2.1)
2261
 
2262
   -------------------------------------------
2263
   -- 3.5.4  Signed Integer Type Definition --
2264
   -------------------------------------------
2265
 
2266
   --  SIGNED_INTEGER_TYPE_DEFINITION ::=
2267
   --    range static_SIMPLE_EXPRESSION .. static_SIMPLE_EXPRESSION
2268
 
2269
   --  Normally the initial token on entry is RANGE, but in some
2270
   --  error conditions, the range token was missing and control is
2271
   --  passed with Token pointing to first token of the first expression.
2272
 
2273
   --  Error recovery: cannot raise Error_Resync
2274
 
2275
   function P_Signed_Integer_Type_Definition return Node_Id is
2276
      Typedef_Node : Node_Id;
2277
      Expr_Node    : Node_Id;
2278
 
2279
   begin
2280
      Typedef_Node := New_Node (N_Signed_Integer_Type_Definition, Token_Ptr);
2281
 
2282
      if Token = Tok_Range then
2283
         Scan; -- past RANGE
2284
      end if;
2285
 
2286
      Expr_Node := P_Expression;
2287
      Check_Simple_Expression (Expr_Node);
2288
      Set_Low_Bound (Typedef_Node, Expr_Node);
2289
      T_Dot_Dot;
2290
      Expr_Node := P_Expression;
2291
      Check_Simple_Expression (Expr_Node);
2292
      Set_High_Bound (Typedef_Node, Expr_Node);
2293
      return Typedef_Node;
2294
   end P_Signed_Integer_Type_Definition;
2295
 
2296
   ------------------------------------
2297
   -- 3.5.4  Modular Type Definition --
2298
   ------------------------------------
2299
 
2300
   --  MODULAR_TYPE_DEFINITION ::= mod static_EXPRESSION
2301
 
2302
   --  The caller has checked that the initial token is MOD
2303
 
2304
   --  Error recovery: cannot raise Error_Resync
2305
 
2306
   function P_Modular_Type_Definition return Node_Id is
2307
      Typedef_Node : Node_Id;
2308
 
2309
   begin
2310
      if Ada_Version = Ada_83 then
2311
         Error_Msg_SC ("(Ada 83): modular types not allowed");
2312
      end if;
2313
 
2314
      Typedef_Node := New_Node (N_Modular_Type_Definition, Token_Ptr);
2315
      Scan; -- past MOD
2316
      Set_Expression (Typedef_Node, P_Expression_No_Right_Paren);
2317
 
2318
      --  Handle mod L..R cleanly
2319
 
2320
      if Token = Tok_Dot_Dot then
2321
         Error_Msg_SC ("range not allowed for modular type");
2322
         Scan; -- past ..
2323
         Set_Expression (Typedef_Node, P_Expression_No_Right_Paren);
2324
      end if;
2325
 
2326
      return Typedef_Node;
2327
   end P_Modular_Type_Definition;
2328
 
2329
   ---------------------------------
2330
   -- 3.5.6  Real Type Definition --
2331
   ---------------------------------
2332
 
2333
   --  Parsed by P_Type_Declaration (3.2.1)
2334
 
2335
   --------------------------------------
2336
   -- 3.5.7  Floating Point Definition --
2337
   --------------------------------------
2338
 
2339
   --  FLOATING_POINT_DEFINITION ::=
2340
   --    digits static_EXPRESSION [REAL_RANGE_SPECIFICATION]
2341
 
2342
   --  Note: In Ada-83, the EXPRESSION must be a SIMPLE_EXPRESSION
2343
 
2344
   --  The caller has checked that the initial token is DIGITS
2345
 
2346
   --  Error recovery: cannot raise Error_Resync
2347
 
2348
   function P_Floating_Point_Definition return Node_Id is
2349
      Digits_Loc : constant Source_Ptr := Token_Ptr;
2350
      Def_Node   : Node_Id;
2351
      Expr_Node  : Node_Id;
2352
 
2353
   begin
2354
      Scan; -- past DIGITS
2355
      Expr_Node := P_Expression_No_Right_Paren;
2356
      Check_Simple_Expression_In_Ada_83 (Expr_Node);
2357
 
2358
      --  Handle decimal fixed-point defn with DIGITS/DELTA in wrong order
2359
 
2360
      if Token = Tok_Delta then
2361
         Error_Msg_SC -- CODEFIX
2362
           ("|DELTA must come before DIGITS");
2363
         Def_Node := New_Node (N_Decimal_Fixed_Point_Definition, Digits_Loc);
2364
         Scan; -- past DELTA
2365
         Set_Delta_Expression (Def_Node, P_Expression_No_Right_Paren);
2366
 
2367
      --  OK floating-point definition
2368
 
2369
      else
2370
         Def_Node := New_Node (N_Floating_Point_Definition, Digits_Loc);
2371
      end if;
2372
 
2373
      Set_Digits_Expression (Def_Node, Expr_Node);
2374
      Set_Real_Range_Specification (Def_Node, P_Real_Range_Specification_Opt);
2375
      return Def_Node;
2376
   end P_Floating_Point_Definition;
2377
 
2378
   -------------------------------------
2379
   -- 3.5.7  Real Range Specification --
2380
   -------------------------------------
2381
 
2382
   --  REAL_RANGE_SPECIFICATION ::=
2383
   --    range static_SIMPLE_EXPRESSION .. static_SIMPLE_EXPRESSION
2384
 
2385
   --  Error recovery: cannot raise Error_Resync
2386
 
2387
   function P_Real_Range_Specification_Opt return Node_Id is
2388
      Specification_Node : Node_Id;
2389
      Expr_Node          : Node_Id;
2390
 
2391
   begin
2392
      if Token = Tok_Range then
2393
         Specification_Node :=
2394
           New_Node (N_Real_Range_Specification, Token_Ptr);
2395
         Scan; -- past RANGE
2396
         Expr_Node := P_Expression_No_Right_Paren;
2397
         Check_Simple_Expression (Expr_Node);
2398
         Set_Low_Bound (Specification_Node, Expr_Node);
2399
         T_Dot_Dot;
2400
         Expr_Node := P_Expression_No_Right_Paren;
2401
         Check_Simple_Expression (Expr_Node);
2402
         Set_High_Bound (Specification_Node, Expr_Node);
2403
         return Specification_Node;
2404
      else
2405
         return Empty;
2406
      end if;
2407
   end P_Real_Range_Specification_Opt;
2408
 
2409
   -----------------------------------
2410
   -- 3.5.9  Fixed Point Definition --
2411
   -----------------------------------
2412
 
2413
   --  FIXED_POINT_DEFINITION ::=
2414
   --    ORDINARY_FIXED_POINT_DEFINITION | DECIMAL_FIXED_POINT_DEFINITION
2415
 
2416
   --  ORDINARY_FIXED_POINT_DEFINITION ::=
2417
   --    delta static_EXPRESSION REAL_RANGE_SPECIFICATION
2418
 
2419
   --  DECIMAL_FIXED_POINT_DEFINITION ::=
2420
   --    delta static_EXPRESSION
2421
   --      digits static_EXPRESSION [REAL_RANGE_SPECIFICATION]
2422
 
2423
   --  The caller has checked that the initial token is DELTA
2424
 
2425
   --  Error recovery: cannot raise Error_Resync
2426
 
2427
   function P_Fixed_Point_Definition return Node_Id is
2428
      Delta_Node : Node_Id;
2429
      Delta_Loc  : Source_Ptr;
2430
      Def_Node   : Node_Id;
2431
      Expr_Node  : Node_Id;
2432
 
2433
   begin
2434
      Delta_Loc := Token_Ptr;
2435
      Scan; -- past DELTA
2436
      Delta_Node := P_Expression_No_Right_Paren;
2437
      Check_Simple_Expression_In_Ada_83 (Delta_Node);
2438
 
2439
      if Token = Tok_Digits then
2440
         if Ada_Version = Ada_83 then
2441
            Error_Msg_SC ("(Ada 83) decimal fixed type not allowed!");
2442
         end if;
2443
 
2444
         Def_Node := New_Node (N_Decimal_Fixed_Point_Definition, Delta_Loc);
2445
         Scan; -- past DIGITS
2446
         Expr_Node := P_Expression_No_Right_Paren;
2447
         Check_Simple_Expression_In_Ada_83 (Expr_Node);
2448
         Set_Digits_Expression (Def_Node, Expr_Node);
2449
 
2450
      else
2451
         Def_Node := New_Node (N_Ordinary_Fixed_Point_Definition, Delta_Loc);
2452
 
2453
         --  Range is required in ordinary fixed point case
2454
 
2455
         if Token /= Tok_Range then
2456
            Error_Msg_AP ("range must be given for fixed-point type");
2457
            T_Range;
2458
         end if;
2459
      end if;
2460
 
2461
      Set_Delta_Expression (Def_Node, Delta_Node);
2462
      Set_Real_Range_Specification (Def_Node, P_Real_Range_Specification_Opt);
2463
      return Def_Node;
2464
   end P_Fixed_Point_Definition;
2465
 
2466
   --------------------------------------------
2467
   -- 3.5.9  Ordinary Fixed Point Definition --
2468
   --------------------------------------------
2469
 
2470
   --  Parsed by P_Fixed_Point_Definition (3.5.9)
2471
 
2472
   -------------------------------------------
2473
   -- 3.5.9  Decimal Fixed Point Definition --
2474
   -------------------------------------------
2475
 
2476
   --  Parsed by P_Decimal_Point_Definition (3.5.9)
2477
 
2478
   ------------------------------
2479
   -- 3.5.9  Digits Constraint --
2480
   ------------------------------
2481
 
2482
   --  DIGITS_CONSTRAINT ::=
2483
   --    digits static_EXPRESSION [RANGE_CONSTRAINT]
2484
 
2485
   --  Note: in Ada 83, the EXPRESSION must be a SIMPLE_EXPRESSION
2486
 
2487
   --  The caller has checked that the initial token is DIGITS
2488
 
2489
   function P_Digits_Constraint return Node_Id is
2490
      Constraint_Node : Node_Id;
2491
      Expr_Node : Node_Id;
2492
 
2493
   begin
2494
      Constraint_Node := New_Node (N_Digits_Constraint, Token_Ptr);
2495
      Scan; -- past DIGITS
2496
      Expr_Node := P_Expression;
2497
      Check_Simple_Expression_In_Ada_83 (Expr_Node);
2498
      Set_Digits_Expression (Constraint_Node, Expr_Node);
2499
 
2500
      if Token = Tok_Range then
2501
         Set_Range_Constraint (Constraint_Node, P_Range_Constraint);
2502
      end if;
2503
 
2504
      return Constraint_Node;
2505
   end P_Digits_Constraint;
2506
 
2507
   -----------------------------
2508
   -- 3.5.9  Delta Constraint --
2509
   -----------------------------
2510
 
2511
   --  DELTA CONSTRAINT ::= DELTA STATIC_EXPRESSION [RANGE_CONSTRAINT]
2512
 
2513
   --  Note: this is an obsolescent feature in Ada 95 (I.3)
2514
 
2515
   --  Note: in Ada 83, the EXPRESSION must be a SIMPLE_EXPRESSION
2516
 
2517
   --  The caller has checked that the initial token is DELTA
2518
 
2519
   --  Error recovery: cannot raise Error_Resync
2520
 
2521
   function P_Delta_Constraint return Node_Id is
2522
      Constraint_Node : Node_Id;
2523
      Expr_Node : Node_Id;
2524
 
2525
   begin
2526
      Constraint_Node := New_Node (N_Delta_Constraint, Token_Ptr);
2527
      Scan; -- past DELTA
2528
      Expr_Node := P_Expression;
2529
      Check_Simple_Expression_In_Ada_83 (Expr_Node);
2530
      Set_Delta_Expression (Constraint_Node, Expr_Node);
2531
 
2532
      if Token = Tok_Range then
2533
         Set_Range_Constraint (Constraint_Node, P_Range_Constraint);
2534
      end if;
2535
 
2536
      return Constraint_Node;
2537
   end P_Delta_Constraint;
2538
 
2539
   --------------------------------
2540
   -- 3.6  Array Type Definition --
2541
   --------------------------------
2542
 
2543
   --  ARRAY_TYPE_DEFINITION ::=
2544
   --    UNCONSTRAINED_ARRAY_DEFINITION | CONSTRAINED_ARRAY_DEFINITION
2545
 
2546
   --  UNCONSTRAINED_ARRAY_DEFINITION ::=
2547
   --    array (INDEX_SUBTYPE_DEFINITION {, INDEX_SUBTYPE_DEFINITION}) of
2548
   --      COMPONENT_DEFINITION
2549
 
2550
   --  INDEX_SUBTYPE_DEFINITION ::= SUBTYPE_MARK range <>
2551
 
2552
   --  CONSTRAINED_ARRAY_DEFINITION ::=
2553
   --    array (DISCRETE_SUBTYPE_DEFINITION {, DISCRETE_SUBTYPE_DEFINITION}) of
2554
   --      COMPONENT_DEFINITION
2555
 
2556
   --  DISCRETE_SUBTYPE_DEFINITION ::=
2557
   --    DISCRETE_SUBTYPE_INDICATION | RANGE
2558
 
2559
   --  COMPONENT_DEFINITION ::=
2560
   --    [aliased] [NULL_EXCLUSION] SUBTYPE_INDICATION | ACCESS_DEFINITION
2561
 
2562
   --  The caller has checked that the initial token is ARRAY
2563
 
2564
   --  Error recovery: can raise Error_Resync
2565
 
2566
   function P_Array_Type_Definition return Node_Id is
2567
      Array_Loc        : Source_Ptr;
2568
      CompDef_Node     : Node_Id;
2569
      Def_Node         : Node_Id;
2570
      Not_Null_Present : Boolean := False;
2571
      Subs_List        : List_Id;
2572
      Scan_State       : Saved_Scan_State;
2573
      Aliased_Present  : Boolean := False;
2574
 
2575
   begin
2576
      Array_Loc := Token_Ptr;
2577
      Scan; -- past ARRAY
2578
      Subs_List := New_List;
2579
      T_Left_Paren;
2580
 
2581
      --  It's quite tricky to disentangle these two possibilities, so we do
2582
      --  a prescan to determine which case we have and then reset the scan.
2583
      --  The prescan skips past possible subtype mark tokens.
2584
 
2585
      Save_Scan_State (Scan_State); -- just after paren
2586
 
2587
      while Token in Token_Class_Desig or else
2588
            Token = Tok_Dot or else
2589
            Token = Tok_Apostrophe -- because of 'BASE, 'CLASS
2590
      loop
2591
         Scan;
2592
      end loop;
2593
 
2594
      --  If we end up on RANGE <> then we have the unconstrained case. We
2595
      --  will also allow the RANGE to be omitted, just to improve error
2596
      --  handling for a case like array (integer <>) of integer;
2597
 
2598
      Scan; -- past possible RANGE or <>
2599
 
2600
      if (Prev_Token = Tok_Range and then Token = Tok_Box) or else
2601
         Prev_Token = Tok_Box
2602
      then
2603
         Def_Node := New_Node (N_Unconstrained_Array_Definition, Array_Loc);
2604
         Restore_Scan_State (Scan_State); -- to first subtype mark
2605
 
2606
         loop
2607
            Append (P_Subtype_Mark_Resync, Subs_List);
2608
            T_Range;
2609
            T_Box;
2610
            exit when Token = Tok_Right_Paren or else Token = Tok_Of;
2611
            T_Comma;
2612
         end loop;
2613
 
2614
         Set_Subtype_Marks (Def_Node, Subs_List);
2615
 
2616
      else
2617
         Def_Node := New_Node (N_Constrained_Array_Definition, Array_Loc);
2618
         Restore_Scan_State (Scan_State); -- to first discrete range
2619
 
2620
         loop
2621
            Append (P_Discrete_Subtype_Definition, Subs_List);
2622
            exit when not Comma_Present;
2623
         end loop;
2624
 
2625
         Set_Discrete_Subtype_Definitions (Def_Node, Subs_List);
2626
      end if;
2627
 
2628
      T_Right_Paren;
2629
      T_Of;
2630
 
2631
      CompDef_Node := New_Node (N_Component_Definition, Token_Ptr);
2632
 
2633
      if Token_Name = Name_Aliased then
2634
         Check_95_Keyword (Tok_Aliased, Tok_Identifier);
2635
      end if;
2636
 
2637
      if Token = Tok_Aliased then
2638
         Aliased_Present := True;
2639
         Scan; -- past ALIASED
2640
      end if;
2641
 
2642
      Not_Null_Present := P_Null_Exclusion; --  Ada 2005 (AI-231/AI-254)
2643
 
2644
      --  Ada 2005 (AI-230): Access Definition case
2645
 
2646
      if Token = Tok_Access then
2647
         if Ada_Version < Ada_05 then
2648
            Error_Msg_SP
2649
              ("generalized use of anonymous access types " &
2650
               "is an Ada 2005 extension");
2651
            Error_Msg_SP ("\unit must be compiled with -gnat05 switch");
2652
         end if;
2653
 
2654
         if Aliased_Present then
2655
            Error_Msg_SP ("ALIASED not allowed here");
2656
         end if;
2657
 
2658
         Set_Subtype_Indication     (CompDef_Node, Empty);
2659
         Set_Aliased_Present        (CompDef_Node, False);
2660
         Set_Access_Definition      (CompDef_Node,
2661
           P_Access_Definition (Not_Null_Present));
2662
      else
2663
 
2664
         Set_Access_Definition      (CompDef_Node, Empty);
2665
         Set_Aliased_Present        (CompDef_Node, Aliased_Present);
2666
         Set_Null_Exclusion_Present (CompDef_Node, Not_Null_Present);
2667
         Set_Subtype_Indication     (CompDef_Node,
2668
           P_Subtype_Indication (Not_Null_Present));
2669
      end if;
2670
 
2671
      Set_Component_Definition (Def_Node, CompDef_Node);
2672
 
2673
      return Def_Node;
2674
   end P_Array_Type_Definition;
2675
 
2676
   -----------------------------------------
2677
   -- 3.6  Unconstrained Array Definition --
2678
   -----------------------------------------
2679
 
2680
   --  Parsed by P_Array_Type_Definition (3.6)
2681
 
2682
   ---------------------------------------
2683
   -- 3.6  Constrained Array Definition --
2684
   ---------------------------------------
2685
 
2686
   --  Parsed by P_Array_Type_Definition (3.6)
2687
 
2688
   --------------------------------------
2689
   -- 3.6  Discrete Subtype Definition --
2690
   --------------------------------------
2691
 
2692
   --  DISCRETE_SUBTYPE_DEFINITION ::=
2693
   --    discrete_SUBTYPE_INDICATION | RANGE
2694
 
2695
   --  Note: the discrete subtype definition appearing in a constrained
2696
   --  array definition is parsed by P_Array_Type_Definition (3.6)
2697
 
2698
   --  Error recovery: cannot raise Error_Resync
2699
 
2700
   function P_Discrete_Subtype_Definition return Node_Id is
2701
   begin
2702
      --  The syntax of a discrete subtype definition is identical to that
2703
      --  of a discrete range, so we simply share the same parsing code.
2704
 
2705
      return P_Discrete_Range;
2706
   end P_Discrete_Subtype_Definition;
2707
 
2708
   -------------------------------
2709
   -- 3.6  Component Definition --
2710
   -------------------------------
2711
 
2712
   --  For the array case, parsed by P_Array_Type_Definition (3.6)
2713
   --  For the record case, parsed by P_Component_Declaration (3.8)
2714
 
2715
   -----------------------------
2716
   -- 3.6.1  Index Constraint --
2717
   -----------------------------
2718
 
2719
   --  Parsed by P_Index_Or_Discriminant_Constraint (3.7.1)
2720
 
2721
   ---------------------------
2722
   -- 3.6.1  Discrete Range --
2723
   ---------------------------
2724
 
2725
   --  DISCRETE_RANGE ::= discrete_SUBTYPE_INDICATION | RANGE
2726
 
2727
   --  The possible forms for a discrete range are:
2728
 
2729
      --   Subtype_Mark                           (SUBTYPE_INDICATION, 3.2.2)
2730
      --   Subtype_Mark range Range               (SUBTYPE_INDICATION, 3.2.2)
2731
      --   Range_Attribute                        (RANGE, 3.5)
2732
      --   Simple_Expression .. Simple_Expression (RANGE, 3.5)
2733
 
2734
   --  Error recovery: cannot raise Error_Resync
2735
 
2736
   function P_Discrete_Range return Node_Id is
2737
      Expr_Node  : Node_Id;
2738
      Range_Node : Node_Id;
2739
 
2740
   begin
2741
      Expr_Node := P_Simple_Expression_Or_Range_Attribute;
2742
 
2743
      if Expr_Form = EF_Range_Attr then
2744
         return Expr_Node;
2745
 
2746
      elsif Token = Tok_Range then
2747
         if Expr_Form /= EF_Simple_Name then
2748
            Error_Msg_SC ("range must be preceded by subtype mark");
2749
         end if;
2750
 
2751
         return P_Subtype_Indication (Expr_Node);
2752
 
2753
      --  Check Expression .. Expression case
2754
 
2755
      elsif Token = Tok_Dot_Dot then
2756
         Range_Node := New_Node (N_Range, Token_Ptr);
2757
         Set_Low_Bound (Range_Node, Expr_Node);
2758
         Scan; -- past ..
2759
         Expr_Node := P_Expression;
2760
         Check_Simple_Expression (Expr_Node);
2761
         Set_High_Bound (Range_Node, Expr_Node);
2762
         return Range_Node;
2763
 
2764
      --  Otherwise we must have a subtype mark
2765
 
2766
      elsif Expr_Form = EF_Simple_Name then
2767
         return Expr_Node;
2768
 
2769
      --  If incorrect, complain that we expect ..
2770
 
2771
      else
2772
         T_Dot_Dot;
2773
         return Expr_Node;
2774
      end if;
2775
   end P_Discrete_Range;
2776
 
2777
   ----------------------------
2778
   -- 3.7  Discriminant Part --
2779
   ----------------------------
2780
 
2781
   --  DISCRIMINANT_PART ::=
2782
   --    UNKNOWN_DISCRIMINANT_PART
2783
   --  | KNOWN_DISCRIMINANT_PART
2784
 
2785
   --  A discriminant part is parsed by P_Known_Discriminant_Part_Opt (3.7)
2786
   --  or P_Unknown_Discriminant_Part (3.7), since we know which we want.
2787
 
2788
   ------------------------------------
2789
   -- 3.7  Unknown Discriminant Part --
2790
   ------------------------------------
2791
 
2792
   --  UNKNOWN_DISCRIMINANT_PART ::= (<>)
2793
 
2794
   --  If no unknown discriminant part is present, then False is returned,
2795
   --  otherwise the unknown discriminant is scanned out and True is returned.
2796
 
2797
   --  Error recovery: cannot raise Error_Resync
2798
 
2799
   function P_Unknown_Discriminant_Part_Opt return Boolean is
2800
      Scan_State : Saved_Scan_State;
2801
 
2802
   begin
2803
      --  If <> right now, then this is missing left paren
2804
 
2805
      if Token = Tok_Box then
2806
         U_Left_Paren;
2807
 
2808
      --  If not <> or left paren, then definitely no box
2809
 
2810
      elsif Token /= Tok_Left_Paren then
2811
         return False;
2812
 
2813
      --  Left paren, so might be a box after it
2814
 
2815
      else
2816
         Save_Scan_State (Scan_State);
2817
         Scan; -- past the left paren
2818
 
2819
         if Token /= Tok_Box then
2820
            Restore_Scan_State (Scan_State);
2821
            return False;
2822
         end if;
2823
      end if;
2824
 
2825
      --  We are now pointing to the box
2826
 
2827
      if Ada_Version = Ada_83 then
2828
         Error_Msg_SC ("(Ada 83) unknown discriminant not allowed!");
2829
      end if;
2830
 
2831
      Scan; -- past the box
2832
      U_Right_Paren; -- must be followed by right paren
2833
      return True;
2834
   end P_Unknown_Discriminant_Part_Opt;
2835
 
2836
   ----------------------------------
2837
   -- 3.7  Known Discriminant Part --
2838
   ----------------------------------
2839
 
2840
   --  KNOWN_DISCRIMINANT_PART ::=
2841
   --    (DISCRIMINANT_SPECIFICATION {; DISCRIMINANT_SPECIFICATION})
2842
 
2843
   --  DISCRIMINANT_SPECIFICATION ::=
2844
   --    DEFINING_IDENTIFIER_LIST : [NULL_EXCLUSION] SUBTYPE_MARK
2845
   --      [:= DEFAULT_EXPRESSION]
2846
   --  | DEFINING_IDENTIFIER_LIST : ACCESS_DEFINITION
2847
   --      [:= DEFAULT_EXPRESSION]
2848
 
2849
   --  If no known discriminant part is present, then No_List is returned
2850
 
2851
   --  Error recovery: cannot raise Error_Resync
2852
 
2853
   function P_Known_Discriminant_Part_Opt return List_Id is
2854
      Specification_Node : Node_Id;
2855
      Specification_List : List_Id;
2856
      Ident_Sloc         : Source_Ptr;
2857
      Scan_State         : Saved_Scan_State;
2858
      Num_Idents         : Nat;
2859
      Not_Null_Present   : Boolean;
2860
      Ident              : Nat;
2861
 
2862
      Idents : array (Int range 1 .. 4096) of Entity_Id;
2863
      --  This array holds the list of defining identifiers. The upper bound
2864
      --  of 4096 is intended to be essentially infinite, and we do not even
2865
      --  bother to check for it being exceeded.
2866
 
2867
   begin
2868
      if Token = Tok_Left_Paren then
2869
         Specification_List := New_List;
2870
         Scan; -- past (
2871
         P_Pragmas_Misplaced;
2872
 
2873
         Specification_Loop : loop
2874
 
2875
            Ident_Sloc := Token_Ptr;
2876
            Idents (1) := P_Defining_Identifier (C_Comma_Colon);
2877
            Num_Idents := 1;
2878
 
2879
            while Comma_Present loop
2880
               Num_Idents := Num_Idents + 1;
2881
               Idents (Num_Idents) := P_Defining_Identifier (C_Comma_Colon);
2882
            end loop;
2883
 
2884
            --  If there are multiple identifiers, we repeatedly scan the
2885
            --  type and initialization expression information by resetting
2886
            --  the scan pointer (so that we get completely separate trees
2887
            --  for each occurrence).
2888
 
2889
            if Num_Idents > 1 then
2890
               Save_Scan_State (Scan_State);
2891
            end if;
2892
 
2893
            T_Colon;
2894
 
2895
            --  Loop through defining identifiers in list
2896
 
2897
            Ident := 1;
2898
            Ident_Loop : loop
2899
               Specification_Node :=
2900
                 New_Node (N_Discriminant_Specification, Ident_Sloc);
2901
               Set_Defining_Identifier (Specification_Node, Idents (Ident));
2902
               Not_Null_Present :=  --  Ada 2005 (AI-231, AI-447)
2903
                 P_Null_Exclusion (Allow_Anonymous_In_95 => True);
2904
 
2905
               if Token = Tok_Access then
2906
                  if Ada_Version = Ada_83 then
2907
                     Error_Msg_SC
2908
                       ("(Ada 83) access discriminant not allowed!");
2909
                  end if;
2910
 
2911
                  Set_Discriminant_Type
2912
                    (Specification_Node,
2913
                     P_Access_Definition (Not_Null_Present));
2914
               else
2915
 
2916
                  Set_Discriminant_Type
2917
                    (Specification_Node, P_Subtype_Mark);
2918
                  No_Constraint;
2919
                  Set_Null_Exclusion_Present  -- Ada 2005 (AI-231)
2920
                    (Specification_Node, Not_Null_Present);
2921
               end if;
2922
 
2923
               Set_Expression
2924
                 (Specification_Node, Init_Expr_Opt (True));
2925
 
2926
               if Ident > 1 then
2927
                  Set_Prev_Ids (Specification_Node, True);
2928
               end if;
2929
 
2930
               if Ident < Num_Idents then
2931
                  Set_More_Ids (Specification_Node, True);
2932
               end if;
2933
 
2934
               Append (Specification_Node, Specification_List);
2935
               exit Ident_Loop when Ident = Num_Idents;
2936
               Ident := Ident + 1;
2937
               Restore_Scan_State (Scan_State);
2938
               T_Colon;
2939
            end loop Ident_Loop;
2940
 
2941
            exit Specification_Loop when Token /= Tok_Semicolon;
2942
            Scan; -- past ;
2943
            P_Pragmas_Misplaced;
2944
         end loop Specification_Loop;
2945
 
2946
         T_Right_Paren;
2947
         return Specification_List;
2948
 
2949
      else
2950
         return No_List;
2951
      end if;
2952
   end P_Known_Discriminant_Part_Opt;
2953
 
2954
   -------------------------------------
2955
   -- 3.7  Discriminant Specification --
2956
   -------------------------------------
2957
 
2958
   --  Parsed by P_Known_Discriminant_Part_Opt (3.7)
2959
 
2960
   -----------------------------
2961
   -- 3.7  Default Expression --
2962
   -----------------------------
2963
 
2964
   --  Always parsed (simply as an Expression) by the parent construct
2965
 
2966
   ------------------------------------
2967
   -- 3.7.1  Discriminant Constraint --
2968
   ------------------------------------
2969
 
2970
   --  Parsed by P_Index_Or_Discriminant_Constraint (3.7.1)
2971
 
2972
   --------------------------------------------------------
2973
   -- 3.7.1  Index or Discriminant Constraint (also 3.6) --
2974
   --------------------------------------------------------
2975
 
2976
   --  DISCRIMINANT_CONSTRAINT ::=
2977
   --    (DISCRIMINANT_ASSOCIATION {, DISCRIMINANT_ASSOCIATION})
2978
 
2979
   --  DISCRIMINANT_ASSOCIATION ::=
2980
   --    [discriminant_SELECTOR_NAME {| discriminant_SELECTOR_NAME} =>]
2981
   --      EXPRESSION
2982
 
2983
   --  This routine parses either an index or a discriminant constraint. As
2984
   --  is clear from the above grammar, it is often possible to clearly
2985
   --  determine which of the two possibilities we have, but there are
2986
   --  cases (those in which we have a series of expressions of the same
2987
   --  syntactic form as subtype indications), where we cannot tell. Since
2988
   --  this means that in any case the semantic phase has to distinguish
2989
   --  between the two, there is not much point in the parser trying to
2990
   --  distinguish even those cases where the difference is clear. In any
2991
   --  case, if we have a situation like:
2992
 
2993
   --     (A => 123, 235 .. 500)
2994
 
2995
   --  it is not clear which of the two items is the wrong one, better to
2996
   --  let the semantic phase give a clear message. Consequently, this
2997
   --  routine in general returns a list of items which can be either
2998
   --  discrete ranges or discriminant associations.
2999
 
3000
   --  The caller has checked that the initial token is a left paren
3001
 
3002
   --  Error recovery: can raise Error_Resync
3003
 
3004
   function P_Index_Or_Discriminant_Constraint return Node_Id is
3005
      Scan_State  : Saved_Scan_State;
3006
      Constr_Node : Node_Id;
3007
      Constr_List : List_Id;
3008
      Expr_Node   : Node_Id;
3009
      Result_Node : Node_Id;
3010
 
3011
   begin
3012
      Result_Node := New_Node (N_Index_Or_Discriminant_Constraint, Token_Ptr);
3013
      Scan; -- past (
3014
      Constr_List := New_List;
3015
      Set_Constraints (Result_Node, Constr_List);
3016
 
3017
      --  The two syntactic forms are a little mixed up, so what we are doing
3018
      --  here is looking at the first entry to determine which case we have
3019
 
3020
      --  A discriminant constraint is a list of discriminant associations,
3021
      --  which have one of the following possible forms:
3022
 
3023
      --    Expression
3024
      --    Id => Expression
3025
      --    Id | Id | .. | Id => Expression
3026
 
3027
      --  An index constraint is a list of discrete ranges which have one
3028
      --  of the following possible forms:
3029
 
3030
      --    Subtype_Mark
3031
      --    Subtype_Mark range Range
3032
      --    Range_Attribute
3033
      --    Simple_Expression .. Simple_Expression
3034
 
3035
      --  Loop through discriminants in list
3036
 
3037
      loop
3038
         --  Check cases of Id => Expression or Id | Id => Expression
3039
 
3040
         if Token = Tok_Identifier then
3041
            Save_Scan_State (Scan_State); -- at Id
3042
            Scan; -- past Id
3043
 
3044
            if Token = Tok_Arrow or else Token = Tok_Vertical_Bar then
3045
               Restore_Scan_State (Scan_State); -- to Id
3046
               Append (P_Discriminant_Association, Constr_List);
3047
               goto Loop_Continue;
3048
            else
3049
               Restore_Scan_State (Scan_State); -- to Id
3050
            end if;
3051
         end if;
3052
 
3053
         --  Otherwise scan out an expression and see what we have got
3054
 
3055
         Expr_Node := P_Expression_Or_Range_Attribute;
3056
 
3057
         if Expr_Form = EF_Range_Attr then
3058
            Append (Expr_Node, Constr_List);
3059
 
3060
         elsif Token = Tok_Range then
3061
            if Expr_Form /= EF_Simple_Name then
3062
               Error_Msg_SC ("subtype mark required before RANGE");
3063
            end if;
3064
 
3065
            Append (P_Subtype_Indication (Expr_Node), Constr_List);
3066
            goto Loop_Continue;
3067
 
3068
         --  Check Simple_Expression .. Simple_Expression case
3069
 
3070
         elsif Token = Tok_Dot_Dot then
3071
            Check_Simple_Expression (Expr_Node);
3072
            Constr_Node := New_Node (N_Range, Token_Ptr);
3073
            Set_Low_Bound (Constr_Node, Expr_Node);
3074
            Scan; -- past ..
3075
            Expr_Node := P_Expression;
3076
            Check_Simple_Expression (Expr_Node);
3077
            Set_High_Bound (Constr_Node, Expr_Node);
3078
            Append (Constr_Node, Constr_List);
3079
            goto Loop_Continue;
3080
 
3081
         --  Case of an expression which could be either form
3082
 
3083
         else
3084
            Append (Expr_Node, Constr_List);
3085
            goto Loop_Continue;
3086
         end if;
3087
 
3088
         --  Here with a single entry scanned
3089
 
3090
         <<Loop_Continue>>
3091
            exit when not Comma_Present;
3092
 
3093
      end loop;
3094
 
3095
      T_Right_Paren;
3096
      return Result_Node;
3097
   end P_Index_Or_Discriminant_Constraint;
3098
 
3099
   -------------------------------------
3100
   -- 3.7.1  Discriminant Association --
3101
   -------------------------------------
3102
 
3103
   --  DISCRIMINANT_ASSOCIATION ::=
3104
   --    [discriminant_SELECTOR_NAME {| discriminant_SELECTOR_NAME} =>]
3105
   --      EXPRESSION
3106
 
3107
   --  This routine is used only when the name list is present and the caller
3108
   --  has already checked this (by scanning ahead and repositioning the
3109
   --  scan).
3110
 
3111
   --  Error_Recovery: cannot raise Error_Resync;
3112
 
3113
   function P_Discriminant_Association return Node_Id is
3114
      Discr_Node : Node_Id;
3115
      Names_List : List_Id;
3116
      Ident_Sloc : Source_Ptr;
3117
 
3118
   begin
3119
      Ident_Sloc := Token_Ptr;
3120
      Names_List := New_List;
3121
 
3122
      loop
3123
         Append (P_Identifier (C_Vertical_Bar_Arrow), Names_List);
3124
         exit when Token /= Tok_Vertical_Bar;
3125
         Scan; -- past |
3126
      end loop;
3127
 
3128
      Discr_Node := New_Node (N_Discriminant_Association, Ident_Sloc);
3129
      Set_Selector_Names (Discr_Node, Names_List);
3130
      TF_Arrow;
3131
      Set_Expression (Discr_Node, P_Expression);
3132
      return Discr_Node;
3133
   end P_Discriminant_Association;
3134
 
3135
   ---------------------------------
3136
   -- 3.8  Record Type Definition --
3137
   ---------------------------------
3138
 
3139
   --  RECORD_TYPE_DEFINITION ::=
3140
   --    [[abstract] tagged] [limited] RECORD_DEFINITION
3141
 
3142
   --  There is no node in the tree for a record type definition. Instead
3143
   --  a record definition node appears, with possible Abstract_Present,
3144
   --  Tagged_Present, and Limited_Present flags set appropriately.
3145
 
3146
   ----------------------------
3147
   -- 3.8  Record Definition --
3148
   ----------------------------
3149
 
3150
   --  RECORD_DEFINITION ::=
3151
   --    record
3152
   --      COMPONENT_LIST
3153
   --    end record
3154
   --  | null record
3155
 
3156
   --  Note: in the case where a record definition node is used to represent
3157
   --  a record type definition, the caller sets the Tagged_Present and
3158
   --  Limited_Present flags in the resulting N_Record_Definition node as
3159
   --  required.
3160
 
3161
   --  Note that the RECORD token at the start may be missing in certain
3162
   --  error situations, so this function is expected to post the error
3163
 
3164
   --  Error recovery: can raise Error_Resync
3165
 
3166
   function P_Record_Definition return Node_Id is
3167
      Rec_Node : Node_Id;
3168
 
3169
   begin
3170
      Rec_Node := New_Node (N_Record_Definition, Token_Ptr);
3171
 
3172
      --  Null record case
3173
 
3174
      if Token = Tok_Null then
3175
         Scan; -- past NULL
3176
         T_Record;
3177
         Set_Null_Present (Rec_Node, True);
3178
 
3179
      --  Catch incomplete declaration to prevent cascaded errors, see
3180
      --  ACATS B393002 for an example.
3181
 
3182
      elsif Token = Tok_Semicolon then
3183
         Error_Msg_AP ("missing record definition");
3184
 
3185
      --  Case starting with RECORD keyword. Build scope stack entry. For the
3186
      --  column, we use the first non-blank character on the line, to deal
3187
      --  with situations such as:
3188
 
3189
      --    type X is record
3190
      --      ...
3191
      --    end record;
3192
 
3193
      --  which is not official RM indentation, but is not uncommon usage, and
3194
      --  in particular is standard GNAT coding style, so handle it nicely.
3195
 
3196
      else
3197
         Push_Scope_Stack;
3198
         Scope.Table (Scope.Last).Etyp := E_Record;
3199
         Scope.Table (Scope.Last).Ecol := Start_Column;
3200
         Scope.Table (Scope.Last).Sloc := Token_Ptr;
3201
         Scope.Table (Scope.Last).Labl := Error;
3202
         Scope.Table (Scope.Last).Junk := (Token /= Tok_Record);
3203
 
3204
         T_Record;
3205
 
3206
         Set_Component_List (Rec_Node, P_Component_List);
3207
 
3208
         loop
3209
            exit when Check_End;
3210
            Discard_Junk_Node (P_Component_List);
3211
         end loop;
3212
      end if;
3213
 
3214
      return Rec_Node;
3215
   end P_Record_Definition;
3216
 
3217
   -------------------------
3218
   -- 3.8  Component List --
3219
   -------------------------
3220
 
3221
   --  COMPONENT_LIST ::=
3222
   --    COMPONENT_ITEM {COMPONENT_ITEM}
3223
   --  | {COMPONENT_ITEM} VARIANT_PART
3224
   --  | null;
3225
 
3226
   --  Error recovery: cannot raise Error_Resync
3227
 
3228
   function P_Component_List return Node_Id is
3229
      Component_List_Node : Node_Id;
3230
      Decls_List          : List_Id;
3231
      Scan_State          : Saved_Scan_State;
3232
 
3233
   begin
3234
      Component_List_Node := New_Node (N_Component_List, Token_Ptr);
3235
      Decls_List := New_List;
3236
 
3237
      if Token = Tok_Null then
3238
         Scan; -- past NULL
3239
         TF_Semicolon;
3240
         P_Pragmas_Opt (Decls_List);
3241
         Set_Null_Present (Component_List_Node, True);
3242
         return Component_List_Node;
3243
 
3244
      else
3245
         P_Pragmas_Opt (Decls_List);
3246
 
3247
         if Token /= Tok_Case then
3248
            Component_Scan_Loop : loop
3249
               P_Component_Items (Decls_List);
3250
               P_Pragmas_Opt (Decls_List);
3251
 
3252
               exit Component_Scan_Loop when Token = Tok_End
3253
                 or else Token = Tok_Case
3254
                 or else Token = Tok_When;
3255
 
3256
               --  We are done if we do not have an identifier. However, if
3257
               --  we have a misspelled reserved identifier that is in a column
3258
               --  to the right of the record definition, we will treat it as
3259
               --  an identifier. It turns out to be too dangerous in practice
3260
               --  to accept such a mis-spelled identifier which does not have
3261
               --  this additional clue that confirms the incorrect spelling.
3262
 
3263
               if Token /= Tok_Identifier then
3264
                  if Start_Column > Scope.Table (Scope.Last).Ecol
3265
                    and then Is_Reserved_Identifier
3266
                  then
3267
                     Save_Scan_State (Scan_State); -- at reserved id
3268
                     Scan; -- possible reserved id
3269
 
3270
                     if Token = Tok_Comma or else Token = Tok_Colon then
3271
                        Restore_Scan_State (Scan_State);
3272
                        Scan_Reserved_Identifier (Force_Msg => True);
3273
 
3274
                     --  Note reserved identifier used as field name after
3275
                     --  all because not followed by colon or comma
3276
 
3277
                     else
3278
                        Restore_Scan_State (Scan_State);
3279
                        exit Component_Scan_Loop;
3280
                     end if;
3281
 
3282
                  --  Non-identifier that definitely was not reserved id
3283
 
3284
                  else
3285
                     exit Component_Scan_Loop;
3286
                  end if;
3287
               end if;
3288
            end loop Component_Scan_Loop;
3289
         end if;
3290
 
3291
         if Token = Tok_Case then
3292
            Set_Variant_Part (Component_List_Node, P_Variant_Part);
3293
 
3294
            --  Check for junk after variant part
3295
 
3296
            if Token = Tok_Identifier then
3297
               Save_Scan_State (Scan_State);
3298
               Scan; -- past identifier
3299
 
3300
               if Token = Tok_Colon then
3301
                  Restore_Scan_State (Scan_State);
3302
                  Error_Msg_SC ("component may not follow variant part");
3303
                  Discard_Junk_Node (P_Component_List);
3304
 
3305
               elsif Token = Tok_Case then
3306
                  Restore_Scan_State (Scan_State);
3307
                  Error_Msg_SC ("only one variant part allowed in a record");
3308
                  Discard_Junk_Node (P_Component_List);
3309
 
3310
               else
3311
                  Restore_Scan_State (Scan_State);
3312
               end if;
3313
            end if;
3314
         end if;
3315
      end if;
3316
 
3317
      Set_Component_Items (Component_List_Node, Decls_List);
3318
      return Component_List_Node;
3319
   end P_Component_List;
3320
 
3321
   -------------------------
3322
   -- 3.8  Component Item --
3323
   -------------------------
3324
 
3325
   --  COMPONENT_ITEM ::= COMPONENT_DECLARATION | REPRESENTATION_CLAUSE
3326
 
3327
   --  COMPONENT_DECLARATION ::=
3328
   --    DEFINING_IDENTIFIER_LIST : COMPONENT_DEFINITION
3329
   --      [:= DEFAULT_EXPRESSION];
3330
 
3331
   --  COMPONENT_DEFINITION ::=
3332
   --    [aliased] [NULL_EXCLUSION] SUBTYPE_INDICATION | ACCESS_DEFINITION
3333
 
3334
   --  Error recovery: cannot raise Error_Resync, if an error occurs,
3335
   --  the scan is positioned past the following semicolon.
3336
 
3337
   --  Note: we do not yet allow representation clauses to appear as component
3338
   --  items, do we need to add this capability sometime in the future ???
3339
 
3340
   procedure P_Component_Items (Decls : List_Id) is
3341
      Aliased_Present  : Boolean := False;
3342
      CompDef_Node     : Node_Id;
3343
      Decl_Node        : Node_Id;
3344
      Scan_State       : Saved_Scan_State;
3345
      Not_Null_Present : Boolean := False;
3346
      Num_Idents       : Nat;
3347
      Ident            : Nat;
3348
      Ident_Sloc       : Source_Ptr;
3349
 
3350
      Idents : array (Int range 1 .. 4096) of Entity_Id;
3351
      --  This array holds the list of defining identifiers. The upper bound
3352
      --  of 4096 is intended to be essentially infinite, and we do not even
3353
      --  bother to check for it being exceeded.
3354
 
3355
   begin
3356
      if Token /= Tok_Identifier then
3357
         Error_Msg_SC ("component declaration expected");
3358
         Resync_Past_Semicolon;
3359
         return;
3360
      end if;
3361
 
3362
      Ident_Sloc := Token_Ptr;
3363
      Idents (1) := P_Defining_Identifier (C_Comma_Colon);
3364
      Num_Idents := 1;
3365
 
3366
      while Comma_Present loop
3367
         Num_Idents := Num_Idents + 1;
3368
         Idents (Num_Idents) := P_Defining_Identifier (C_Comma_Colon);
3369
      end loop;
3370
 
3371
      --  If there are multiple identifiers, we repeatedly scan the
3372
      --  type and initialization expression information by resetting
3373
      --  the scan pointer (so that we get completely separate trees
3374
      --  for each occurrence).
3375
 
3376
      if Num_Idents > 1 then
3377
         Save_Scan_State (Scan_State);
3378
      end if;
3379
 
3380
      T_Colon;
3381
 
3382
      --  Loop through defining identifiers in list
3383
 
3384
      Ident := 1;
3385
      Ident_Loop : loop
3386
 
3387
         --  The following block is present to catch Error_Resync
3388
         --  which causes the parse to be reset past the semicolon
3389
 
3390
         begin
3391
            Decl_Node := New_Node (N_Component_Declaration, Ident_Sloc);
3392
            Set_Defining_Identifier (Decl_Node, Idents (Ident));
3393
 
3394
            if Token = Tok_Constant then
3395
               Error_Msg_SC ("constant components are not permitted");
3396
               Scan;
3397
            end if;
3398
 
3399
            CompDef_Node := New_Node (N_Component_Definition, Token_Ptr);
3400
 
3401
            if Token_Name = Name_Aliased then
3402
               Check_95_Keyword (Tok_Aliased, Tok_Identifier);
3403
            end if;
3404
 
3405
            if Token = Tok_Aliased then
3406
               Aliased_Present := True;
3407
               Scan; -- past ALIASED
3408
            end if;
3409
 
3410
            Not_Null_Present := P_Null_Exclusion; -- Ada 2005 (AI-231/AI-254)
3411
 
3412
            --  Ada 2005 (AI-230): Access Definition case
3413
 
3414
            if Token = Tok_Access then
3415
               if Ada_Version < Ada_05 then
3416
                  Error_Msg_SP
3417
                    ("generalized use of anonymous access types " &
3418
                     "is an Ada 2005 extension");
3419
                  Error_Msg_SP ("\unit must be compiled with -gnat05 switch");
3420
               end if;
3421
 
3422
               if Aliased_Present then
3423
                  Error_Msg_SP ("ALIASED not allowed here");
3424
               end if;
3425
 
3426
               Set_Subtype_Indication (CompDef_Node, Empty);
3427
               Set_Aliased_Present    (CompDef_Node, False);
3428
               Set_Access_Definition  (CompDef_Node,
3429
                 P_Access_Definition (Not_Null_Present));
3430
            else
3431
 
3432
               Set_Access_Definition      (CompDef_Node, Empty);
3433
               Set_Aliased_Present        (CompDef_Node, Aliased_Present);
3434
               Set_Null_Exclusion_Present (CompDef_Node, Not_Null_Present);
3435
 
3436
               if Token = Tok_Array then
3437
                  Error_Msg_SC
3438
                    ("anonymous arrays not allowed as components");
3439
                  raise Error_Resync;
3440
               end if;
3441
 
3442
               Set_Subtype_Indication (CompDef_Node,
3443
                 P_Subtype_Indication (Not_Null_Present));
3444
            end if;
3445
 
3446
            Set_Component_Definition (Decl_Node, CompDef_Node);
3447
            Set_Expression           (Decl_Node, Init_Expr_Opt);
3448
 
3449
            if Ident > 1 then
3450
               Set_Prev_Ids (Decl_Node, True);
3451
            end if;
3452
 
3453
            if Ident < Num_Idents then
3454
               Set_More_Ids (Decl_Node, True);
3455
            end if;
3456
 
3457
            Append (Decl_Node, Decls);
3458
 
3459
         exception
3460
            when Error_Resync =>
3461
               if Token /= Tok_End then
3462
                  Resync_Past_Semicolon;
3463
               end if;
3464
         end;
3465
 
3466
         exit Ident_Loop when Ident = Num_Idents;
3467
         Ident := Ident + 1;
3468
         Restore_Scan_State (Scan_State);
3469
         T_Colon;
3470
 
3471
      end loop Ident_Loop;
3472
 
3473
      TF_Semicolon;
3474
   end P_Component_Items;
3475
 
3476
   --------------------------------
3477
   -- 3.8  Component Declaration --
3478
   --------------------------------
3479
 
3480
   --  Parsed by P_Component_Items (3.8)
3481
 
3482
   -------------------------
3483
   -- 3.8.1  Variant Part --
3484
   -------------------------
3485
 
3486
   --  VARIANT_PART ::=
3487
   --    case discriminant_DIRECT_NAME is
3488
   --      VARIANT
3489
   --      {VARIANT}
3490
   --    end case;
3491
 
3492
   --  The caller has checked that the initial token is CASE
3493
 
3494
   --  Error recovery: cannot raise Error_Resync
3495
 
3496
   function P_Variant_Part return Node_Id is
3497
      Variant_Part_Node : Node_Id;
3498
      Variants_List     : List_Id;
3499
      Case_Node         : Node_Id;
3500
 
3501
   begin
3502
      Variant_Part_Node := New_Node (N_Variant_Part, Token_Ptr);
3503
      Push_Scope_Stack;
3504
      Scope.Table (Scope.Last).Etyp := E_Case;
3505
      Scope.Table (Scope.Last).Sloc := Token_Ptr;
3506
      Scope.Table (Scope.Last).Ecol := Start_Column;
3507
 
3508
      Scan; -- past CASE
3509
      Case_Node := P_Expression;
3510
      Set_Name (Variant_Part_Node, Case_Node);
3511
 
3512
      if Nkind (Case_Node) /= N_Identifier then
3513
         Set_Name (Variant_Part_Node, Error);
3514
         Error_Msg ("discriminant name expected", Sloc (Case_Node));
3515
 
3516
      elsif Paren_Count (Case_Node) /= 0 then
3517
         Error_Msg ("|discriminant name may not be parenthesized",
3518
                    Sloc (Case_Node));
3519
         Set_Paren_Count (Case_Node, 0);
3520
      end if;
3521
 
3522
      TF_Is;
3523
      Variants_List := New_List;
3524
      P_Pragmas_Opt (Variants_List);
3525
 
3526
      --  Test missing variant
3527
 
3528
      if Token = Tok_End then
3529
         Error_Msg_BC ("WHEN expected (must have at least one variant)");
3530
      else
3531
         Append (P_Variant, Variants_List);
3532
      end if;
3533
 
3534
      --  Loop through variants, note that we allow if in place of when,
3535
      --  this error will be detected and handled in P_Variant.
3536
 
3537
      loop
3538
         P_Pragmas_Opt (Variants_List);
3539
 
3540
         if Token /= Tok_When
3541
           and then Token /= Tok_If
3542
           and then Token /= Tok_Others
3543
         then
3544
            exit when Check_End;
3545
         end if;
3546
 
3547
         Append (P_Variant, Variants_List);
3548
      end loop;
3549
 
3550
      Set_Variants (Variant_Part_Node, Variants_List);
3551
      return Variant_Part_Node;
3552
   end P_Variant_Part;
3553
 
3554
   --------------------
3555
   -- 3.8.1  Variant --
3556
   --------------------
3557
 
3558
   --  VARIANT ::=
3559
   --    when DISCRETE_CHOICE_LIST =>
3560
   --      COMPONENT_LIST
3561
 
3562
   --  Error recovery: cannot raise Error_Resync
3563
 
3564
   --  The initial token on entry is either WHEN, IF or OTHERS
3565
 
3566
   function P_Variant return Node_Id is
3567
      Variant_Node : Node_Id;
3568
 
3569
   begin
3570
      --  Special check to recover nicely from use of IF in place of WHEN
3571
 
3572
      if Token = Tok_If then
3573
         T_When;
3574
         Scan; -- past IF
3575
      else
3576
         T_When;
3577
      end if;
3578
 
3579
      Variant_Node := New_Node (N_Variant, Prev_Token_Ptr);
3580
      Set_Discrete_Choices (Variant_Node, P_Discrete_Choice_List);
3581
      TF_Arrow;
3582
      Set_Component_List (Variant_Node, P_Component_List);
3583
      return Variant_Node;
3584
   end P_Variant;
3585
 
3586
   ---------------------------------
3587
   -- 3.8.1  Discrete Choice List --
3588
   ---------------------------------
3589
 
3590
   --  DISCRETE_CHOICE_LIST ::= DISCRETE_CHOICE {| DISCRETE_CHOICE}
3591
 
3592
   --  DISCRETE_CHOICE ::= EXPRESSION | DISCRETE_RANGE | others
3593
 
3594
   --  Note: in Ada 83, the expression must be a simple expression
3595
 
3596
   --  Error recovery: cannot raise Error_Resync
3597
 
3598
   function P_Discrete_Choice_List return List_Id is
3599
      Choices     : List_Id;
3600
      Expr_Node   : Node_Id;
3601
      Choice_Node : Node_Id;
3602
 
3603
   begin
3604
      Choices := New_List;
3605
      loop
3606
         if Token = Tok_Others then
3607
            Append (New_Node (N_Others_Choice, Token_Ptr), Choices);
3608
            Scan; -- past OTHERS
3609
 
3610
         else
3611
            begin
3612
               --  Scan out expression or range attribute
3613
 
3614
               Expr_Node := P_Expression_Or_Range_Attribute;
3615
               Ignore (Tok_Right_Paren);
3616
 
3617
               if Token = Tok_Colon
3618
                 and then Nkind (Expr_Node) = N_Identifier
3619
               then
3620
                  Error_Msg_SP ("label not permitted in this context");
3621
                  Scan; -- past colon
3622
 
3623
               --  Range attribute
3624
 
3625
               elsif Expr_Form = EF_Range_Attr then
3626
                  Append (Expr_Node, Choices);
3627
 
3628
               --  Explicit range
3629
 
3630
               elsif Token = Tok_Dot_Dot then
3631
                  Check_Simple_Expression (Expr_Node);
3632
                  Choice_Node := New_Node (N_Range, Token_Ptr);
3633
                  Set_Low_Bound (Choice_Node, Expr_Node);
3634
                  Scan; -- past ..
3635
                  Expr_Node := P_Expression_No_Right_Paren;
3636
                  Check_Simple_Expression (Expr_Node);
3637
                  Set_High_Bound (Choice_Node, Expr_Node);
3638
                  Append (Choice_Node, Choices);
3639
 
3640
               --  Simple name, must be subtype, so range allowed
3641
 
3642
               elsif Expr_Form = EF_Simple_Name then
3643
                  if Token = Tok_Range then
3644
                     Append (P_Subtype_Indication (Expr_Node), Choices);
3645
 
3646
                  elsif Token in Token_Class_Consk then
3647
                     Error_Msg_SC
3648
                       ("the only constraint allowed here " &
3649
                        "is a range constraint");
3650
                     Discard_Junk_Node (P_Constraint_Opt);
3651
                     Append (Expr_Node, Choices);
3652
 
3653
                  else
3654
                     Append (Expr_Node, Choices);
3655
                  end if;
3656
 
3657
               --  Expression
3658
 
3659
               else
3660
                  --  If extensions are permitted then the expression must be a
3661
                  --  simple expression. The resaon for this restriction (i.e.
3662
                  --  going back to the Ada 83 rule) is to avoid ambiguities
3663
                  --  when set membership operations are allowed, consider the
3664
                  --  following:
3665
 
3666
                  --     when A in 1 .. 10 | 12 =>
3667
 
3668
                  --  This is ambiguous without parentheses, so we require one
3669
                  --  of the following two parenthesized forms to disambuguate:
3670
 
3671
                  --  one of the following:
3672
 
3673
                  --     when (A in 1 .. 10 | 12) =>
3674
                  --     when (A in 1 .. 10) | 12 =>
3675
 
3676
                  --  To solve this, if extensins are enabled, we disallow
3677
                  --  the use of membership operations in expressions in
3678
                  --  choices. Technically in the grammar, the expression
3679
                  --  must match the grammar for restricted expression.
3680
 
3681
                  if Extensions_Allowed then
3682
                     Check_Restricted_Expression (Expr_Node);
3683
 
3684
                  --  In Ada 83 mode, the syntax required a simple expression
3685
 
3686
                  else
3687
                     Check_Simple_Expression_In_Ada_83 (Expr_Node);
3688
                  end if;
3689
 
3690
                  Append (Expr_Node, Choices);
3691
               end if;
3692
 
3693
            exception
3694
               when Error_Resync =>
3695
                  Resync_Choice;
3696
                  return Error_List;
3697
            end;
3698
         end if;
3699
 
3700
         if Token = Tok_Comma then
3701
            Error_Msg_SC (""","" should be ""'|""");
3702
         else
3703
            exit when Token /= Tok_Vertical_Bar;
3704
         end if;
3705
 
3706
         Scan; -- past | or comma
3707
      end loop;
3708
 
3709
      return Choices;
3710
   end P_Discrete_Choice_List;
3711
 
3712
   ----------------------------
3713
   -- 3.8.1  Discrete Choice --
3714
   ----------------------------
3715
 
3716
   --  Parsed by P_Discrete_Choice_List (3.8.1)
3717
 
3718
   ----------------------------------
3719
   -- 3.9.1  Record Extension Part --
3720
   ----------------------------------
3721
 
3722
   --  RECORD_EXTENSION_PART ::= with RECORD_DEFINITION
3723
 
3724
   --  Parsed by P_Derived_Type_Def_Or_Private_Ext_Decl (3.4)
3725
 
3726
   --------------------------------------
3727
   -- 3.9.4  Interface Type Definition --
3728
   --------------------------------------
3729
 
3730
   --  INTERFACE_TYPE_DEFINITION ::=
3731
   --    [limited | task | protected | synchronized] interface
3732
   --      [and INTERFACE_LIST]
3733
 
3734
   --  Error recovery: cannot raise Error_Resync
3735
 
3736
   function P_Interface_Type_Definition
3737
     (Abstract_Present : Boolean) return Node_Id
3738
   is
3739
      Typedef_Node : Node_Id;
3740
 
3741
   begin
3742
      if Ada_Version < Ada_05 then
3743
         Error_Msg_SP ("abstract interface is an Ada 2005 extension");
3744
         Error_Msg_SP ("\unit must be compiled with -gnat05 switch");
3745
      end if;
3746
 
3747
      if Abstract_Present then
3748
         Error_Msg_SP ("ABSTRACT not allowed in interface type definition " &
3749
                       "(RM 3.9.4(2/2))");
3750
      end if;
3751
 
3752
      Scan; -- past INTERFACE
3753
 
3754
      --  Ada 2005 (AI-345): In case of interfaces with a null list of
3755
      --  interfaces we build a record_definition node.
3756
 
3757
      if Token = Tok_Semicolon then
3758
         Typedef_Node := New_Node (N_Record_Definition, Token_Ptr);
3759
 
3760
         Set_Abstract_Present  (Typedef_Node);
3761
         Set_Tagged_Present    (Typedef_Node);
3762
         Set_Null_Present      (Typedef_Node);
3763
         Set_Interface_Present (Typedef_Node);
3764
 
3765
      --  Ada 2005 (AI-251): In case of not-synchronized interfaces that have
3766
      --  a list of interfaces we build a derived_type_definition node. This
3767
      --  simplifies the semantic analysis (and hence further maintenance)
3768
 
3769
      else
3770
         if Token /= Tok_And then
3771
            Error_Msg_AP ("AND expected");
3772
         else
3773
            Scan; -- past AND
3774
         end if;
3775
 
3776
         Typedef_Node := New_Node (N_Derived_Type_Definition, Token_Ptr);
3777
 
3778
         Set_Abstract_Present   (Typedef_Node);
3779
         Set_Interface_Present  (Typedef_Node);
3780
         Set_Subtype_Indication (Typedef_Node, P_Qualified_Simple_Name);
3781
 
3782
         Set_Record_Extension_Part (Typedef_Node,
3783
           New_Node (N_Record_Definition, Token_Ptr));
3784
         Set_Null_Present (Record_Extension_Part (Typedef_Node));
3785
 
3786
         if Token = Tok_And then
3787
            Set_Interface_List (Typedef_Node, New_List);
3788
            Scan; -- past AND
3789
 
3790
            loop
3791
               Append (P_Qualified_Simple_Name,
3792
                       Interface_List (Typedef_Node));
3793
               exit when Token /= Tok_And;
3794
               Scan; -- past AND
3795
            end loop;
3796
         end if;
3797
      end if;
3798
 
3799
      return Typedef_Node;
3800
   end P_Interface_Type_Definition;
3801
 
3802
   ----------------------------------
3803
   -- 3.10  Access Type Definition --
3804
   ----------------------------------
3805
 
3806
   --  ACCESS_TYPE_DEFINITION ::=
3807
   --    ACCESS_TO_OBJECT_DEFINITION
3808
   --  | ACCESS_TO_SUBPROGRAM_DEFINITION
3809
 
3810
   --  ACCESS_TO_OBJECT_DEFINITION ::=
3811
   --    [NULL_EXCLUSION] access [GENERAL_ACCESS_MODIFIER] SUBTYPE_INDICATION
3812
 
3813
   --  GENERAL_ACCESS_MODIFIER ::= all | constant
3814
 
3815
   --  ACCESS_TO_SUBPROGRAM_DEFINITION
3816
   --    [NULL_EXCLUSION] access [protected] procedure PARAMETER_PROFILE
3817
   --  | [NULL_EXCLUSION] access [protected] function
3818
   --    PARAMETER_AND_RESULT_PROFILE
3819
 
3820
   --  PARAMETER_PROFILE ::= [FORMAL_PART]
3821
 
3822
   --  PARAMETER_AND_RESULT_PROFILE ::= [FORMAL_PART] RETURN SUBTYPE_MARK
3823
 
3824
   --  Ada 2005 (AI-254): If Header_Already_Parsed then the caller has already
3825
   --  parsed the null_exclusion part and has also removed the ACCESS token;
3826
   --  otherwise the caller has just checked that the initial token is ACCESS
3827
 
3828
   --  Error recovery: can raise Error_Resync
3829
 
3830
   function P_Access_Type_Definition
3831
     (Header_Already_Parsed : Boolean := False) return Node_Id
3832
   is
3833
      Access_Loc       : constant Source_Ptr := Token_Ptr;
3834
      Prot_Flag        : Boolean;
3835
      Not_Null_Present : Boolean := False;
3836
      Type_Def_Node    : Node_Id;
3837
      Result_Not_Null  : Boolean;
3838
      Result_Node      : Node_Id;
3839
 
3840
      procedure Check_Junk_Subprogram_Name;
3841
      --  Used in access to subprogram definition cases to check for an
3842
      --  identifier or operator symbol that does not belong.
3843
 
3844
      --------------------------------
3845
      -- Check_Junk_Subprogram_Name --
3846
      --------------------------------
3847
 
3848
      procedure Check_Junk_Subprogram_Name is
3849
         Saved_State : Saved_Scan_State;
3850
 
3851
      begin
3852
         if Token = Tok_Identifier or else Token = Tok_Operator_Symbol then
3853
            Save_Scan_State (Saved_State);
3854
            Scan; -- past possible junk subprogram name
3855
 
3856
            if Token = Tok_Left_Paren or else Token = Tok_Semicolon then
3857
               Error_Msg_SP ("unexpected subprogram name ignored");
3858
               return;
3859
 
3860
            else
3861
               Restore_Scan_State (Saved_State);
3862
            end if;
3863
         end if;
3864
      end Check_Junk_Subprogram_Name;
3865
 
3866
   --  Start of processing for P_Access_Type_Definition
3867
 
3868
   begin
3869
      if not Header_Already_Parsed then
3870
         Not_Null_Present := P_Null_Exclusion;         --  Ada 2005 (AI-231)
3871
         Scan; -- past ACCESS
3872
      end if;
3873
 
3874
      if Token_Name = Name_Protected then
3875
         Check_95_Keyword (Tok_Protected, Tok_Procedure);
3876
         Check_95_Keyword (Tok_Protected, Tok_Function);
3877
      end if;
3878
 
3879
      Prot_Flag := (Token = Tok_Protected);
3880
 
3881
      if Prot_Flag then
3882
         Scan; -- past PROTECTED
3883
 
3884
         if Token /= Tok_Procedure and then Token /= Tok_Function then
3885
            Error_Msg_SC -- CODEFIX
3886
              ("FUNCTION or PROCEDURE expected");
3887
         end if;
3888
      end if;
3889
 
3890
      if Token = Tok_Procedure then
3891
         if Ada_Version = Ada_83 then
3892
            Error_Msg_SC ("(Ada 83) access to procedure not allowed!");
3893
         end if;
3894
 
3895
         Type_Def_Node := New_Node (N_Access_Procedure_Definition, Access_Loc);
3896
         Set_Null_Exclusion_Present (Type_Def_Node, Not_Null_Present);
3897
         Scan; -- past PROCEDURE
3898
         Check_Junk_Subprogram_Name;
3899
         Set_Parameter_Specifications (Type_Def_Node, P_Parameter_Profile);
3900
         Set_Protected_Present (Type_Def_Node, Prot_Flag);
3901
 
3902
      elsif Token = Tok_Function then
3903
         if Ada_Version = Ada_83 then
3904
            Error_Msg_SC ("(Ada 83) access to function not allowed!");
3905
         end if;
3906
 
3907
         Type_Def_Node := New_Node (N_Access_Function_Definition, Access_Loc);
3908
         Set_Null_Exclusion_Present (Type_Def_Node, Not_Null_Present);
3909
         Scan; -- past FUNCTION
3910
         Check_Junk_Subprogram_Name;
3911
         Set_Parameter_Specifications (Type_Def_Node, P_Parameter_Profile);
3912
         Set_Protected_Present (Type_Def_Node, Prot_Flag);
3913
         TF_Return;
3914
 
3915
         Result_Not_Null := P_Null_Exclusion;     --  Ada 2005 (AI-231)
3916
 
3917
         --  Ada 2005 (AI-318-02)
3918
 
3919
         if Token = Tok_Access then
3920
            if Ada_Version < Ada_05 then
3921
               Error_Msg_SC
3922
                 ("anonymous access result type is an Ada 2005 extension");
3923
               Error_Msg_SC ("\unit must be compiled with -gnat05 switch");
3924
            end if;
3925
 
3926
            Result_Node := P_Access_Definition (Result_Not_Null);
3927
 
3928
         else
3929
            Result_Node := P_Subtype_Mark;
3930
            No_Constraint;
3931
 
3932
            --  A null exclusion on the result type must be recorded in a flag
3933
            --  distinct from the one used for the access-to-subprogram type's
3934
            --  null exclusion.
3935
 
3936
            Set_Null_Exclusion_In_Return_Present
3937
              (Type_Def_Node, Result_Not_Null);
3938
         end if;
3939
 
3940
         Set_Result_Definition (Type_Def_Node, Result_Node);
3941
 
3942
      else
3943
         Type_Def_Node :=
3944
           New_Node (N_Access_To_Object_Definition, Access_Loc);
3945
         Set_Null_Exclusion_Present (Type_Def_Node, Not_Null_Present);
3946
 
3947
         if Token = Tok_All or else Token = Tok_Constant then
3948
            if Ada_Version = Ada_83 then
3949
               Error_Msg_SC ("(Ada 83) access modifier not allowed!");
3950
            end if;
3951
 
3952
            if Token = Tok_All then
3953
               Set_All_Present (Type_Def_Node, True);
3954
 
3955
            else
3956
               Set_Constant_Present (Type_Def_Node, True);
3957
            end if;
3958
 
3959
            Scan; -- past ALL or CONSTANT
3960
         end if;
3961
 
3962
         Set_Subtype_Indication (Type_Def_Node,
3963
            P_Subtype_Indication (Not_Null_Present));
3964
      end if;
3965
 
3966
      return Type_Def_Node;
3967
   end P_Access_Type_Definition;
3968
 
3969
   ---------------------------------------
3970
   -- 3.10  Access To Object Definition --
3971
   ---------------------------------------
3972
 
3973
   --  Parsed by P_Access_Type_Definition (3.10)
3974
 
3975
   -----------------------------------
3976
   -- 3.10  General Access Modifier --
3977
   -----------------------------------
3978
 
3979
   --  Parsed by P_Access_Type_Definition (3.10)
3980
 
3981
   -------------------------------------------
3982
   -- 3.10  Access To Subprogram Definition --
3983
   -------------------------------------------
3984
 
3985
   --  Parsed by P_Access_Type_Definition (3.10)
3986
 
3987
   -----------------------------
3988
   -- 3.10  Access Definition --
3989
   -----------------------------
3990
 
3991
   --  ACCESS_DEFINITION ::=
3992
   --    [NULL_EXCLUSION] access [GENERAL_ACCESS_MODIFIER] SUBTYPE_MARK
3993
   --  | ACCESS_TO_SUBPROGRAM_DEFINITION
3994
   --
3995
   --  ACCESS_TO_SUBPROGRAM_DEFINITION
3996
   --    [NULL_EXCLUSION] access [protected] procedure PARAMETER_PROFILE
3997
   --  | [NULL_EXCLUSION] access [protected] function
3998
   --    PARAMETER_AND_RESULT_PROFILE
3999
 
4000
   --  The caller has parsed the null-exclusion part and it has also checked
4001
   --  that the next token is ACCESS
4002
 
4003
   --  Error recovery: cannot raise Error_Resync
4004
 
4005
   function P_Access_Definition
4006
     (Null_Exclusion_Present : Boolean) return Node_Id
4007
   is
4008
      Def_Node  : Node_Id;
4009
      Subp_Node : Node_Id;
4010
 
4011
   begin
4012
      Def_Node := New_Node (N_Access_Definition, Token_Ptr);
4013
      Scan; -- past ACCESS
4014
 
4015
      --  Ada 2005 (AI-254): Access_To_Subprogram_Definition
4016
 
4017
      if Token = Tok_Protected
4018
        or else Token = Tok_Procedure
4019
        or else Token = Tok_Function
4020
      then
4021
         if Ada_Version < Ada_05 then
4022
            Error_Msg_SP ("access-to-subprogram is an Ada 2005 extension");
4023
            Error_Msg_SP ("\unit should be compiled with -gnat05 switch");
4024
         end if;
4025
 
4026
         Subp_Node := P_Access_Type_Definition (Header_Already_Parsed => True);
4027
         Set_Null_Exclusion_Present (Subp_Node, Null_Exclusion_Present);
4028
         Set_Access_To_Subprogram_Definition (Def_Node, Subp_Node);
4029
 
4030
      --  Ada 2005 (AI-231)
4031
      --  [NULL_EXCLUSION] access [GENERAL_ACCESS_MODIFIER] SUBTYPE_MARK
4032
 
4033
      else
4034
         Set_Null_Exclusion_Present (Def_Node, Null_Exclusion_Present);
4035
 
4036
         if Token = Tok_All then
4037
            if Ada_Version < Ada_05 then
4038
               Error_Msg_SP
4039
                 ("ALL is not permitted for anonymous access types");
4040
            end if;
4041
 
4042
            Scan; -- past ALL
4043
            Set_All_Present (Def_Node);
4044
 
4045
         elsif Token = Tok_Constant then
4046
            if Ada_Version < Ada_05 then
4047
               Error_Msg_SP ("access-to-constant is an Ada 2005 extension");
4048
               Error_Msg_SP ("\unit should be compiled with -gnat05 switch");
4049
            end if;
4050
 
4051
            Scan; -- past CONSTANT
4052
            Set_Constant_Present (Def_Node);
4053
         end if;
4054
 
4055
         Set_Subtype_Mark (Def_Node, P_Subtype_Mark);
4056
         No_Constraint;
4057
      end if;
4058
 
4059
      return Def_Node;
4060
   end P_Access_Definition;
4061
 
4062
   -----------------------------------------
4063
   -- 3.10.1  Incomplete Type Declaration --
4064
   -----------------------------------------
4065
 
4066
   --  Parsed by P_Type_Declaration (3.2.1)
4067
 
4068
   ----------------------------
4069
   -- 3.11  Declarative Part --
4070
   ----------------------------
4071
 
4072
   --  DECLARATIVE_PART ::= {DECLARATIVE_ITEM}
4073
 
4074
   --  Error recovery: cannot raise Error_Resync (because P_Declarative_Items
4075
   --  handles errors, and returns cleanly after an error has occurred)
4076
 
4077
   function P_Declarative_Part return List_Id is
4078
      Decls : List_Id;
4079
      Done  : Boolean;
4080
 
4081
   begin
4082
      --  Indicate no bad declarations detected yet. This will be reset by
4083
      --  P_Declarative_Items if a bad declaration is discovered.
4084
 
4085
      Missing_Begin_Msg := No_Error_Msg;
4086
 
4087
      --  Get rid of active SIS entry from outer scope. This means we will
4088
      --  miss some nested cases, but it doesn't seem worth the effort. See
4089
      --  discussion in Par for further details
4090
 
4091
      SIS_Entry_Active := False;
4092
      Decls := New_List;
4093
 
4094
      --  Loop to scan out the declarations
4095
 
4096
      loop
4097
         P_Declarative_Items (Decls, Done, In_Spec => False);
4098
         exit when Done;
4099
      end loop;
4100
 
4101
      --  Get rid of active SIS entry which is left set only if we scanned a
4102
      --  procedure declaration and have not found the body. We could give
4103
      --  an error message, but that really would be usurping the role of
4104
      --  semantic analysis (this really is a missing body case).
4105
 
4106
      SIS_Entry_Active := False;
4107
      return Decls;
4108
   end P_Declarative_Part;
4109
 
4110
   ----------------------------
4111
   -- 3.11  Declarative Item --
4112
   ----------------------------
4113
 
4114
   --  DECLARATIVE_ITEM ::= BASIC_DECLARATIVE_ITEM | BODY
4115
 
4116
   --  Can return Error if a junk declaration is found, or Empty if no
4117
   --  declaration is found (i.e. a token ending declarations, such as
4118
   --  BEGIN or END is encountered).
4119
 
4120
   --  Error recovery: cannot raise Error_Resync. If an error resync occurs,
4121
   --  then the scan is set past the next semicolon and Error is returned.
4122
 
4123
   procedure P_Declarative_Items
4124
     (Decls   : List_Id;
4125
      Done    : out Boolean;
4126
      In_Spec : Boolean)
4127
   is
4128
      Scan_State : Saved_Scan_State;
4129
 
4130
   begin
4131
      if Style_Check then
4132
         Style.Check_Indentation;
4133
      end if;
4134
 
4135
      case Token is
4136
 
4137
         when Tok_Function =>
4138
            Check_Bad_Layout;
4139
            Append (P_Subprogram (Pf_Decl_Gins_Pbod_Rnam_Stub), Decls);
4140
            Done := False;
4141
 
4142
         when Tok_For =>
4143
            Check_Bad_Layout;
4144
 
4145
            --  Check for loop (premature statement)
4146
 
4147
            Save_Scan_State (Scan_State);
4148
            Scan; -- past FOR
4149
 
4150
            if Token = Tok_Identifier then
4151
               Scan; -- past identifier
4152
 
4153
               if Token = Tok_In then
4154
                  Restore_Scan_State (Scan_State);
4155
                  Statement_When_Declaration_Expected (Decls, Done, In_Spec);
4156
                  return;
4157
               end if;
4158
            end if;
4159
 
4160
            --  Not a loop, so must be rep clause
4161
 
4162
            Restore_Scan_State (Scan_State);
4163
            Append (P_Representation_Clause, Decls);
4164
            Done := False;
4165
 
4166
         when Tok_Generic =>
4167
            Check_Bad_Layout;
4168
            Append (P_Generic, Decls);
4169
            Done := False;
4170
 
4171
         when Tok_Identifier =>
4172
            Check_Bad_Layout;
4173
 
4174
            --  Special check for misuse of overriding not in Ada 2005 mode
4175
 
4176
            if Token_Name = Name_Overriding
4177
              and then not Next_Token_Is (Tok_Colon)
4178
            then
4179
               Error_Msg_SC ("overriding indicator is an Ada 2005 extension");
4180
               Error_Msg_SC ("\unit must be compiled with -gnat05 switch");
4181
 
4182
               Token := Tok_Overriding;
4183
               Append (P_Subprogram (Pf_Decl_Gins_Pbod_Rnam_Stub), Decls);
4184
               Done := False;
4185
 
4186
            --  Normal case, no overriding, or overriding followed by colon
4187
 
4188
            else
4189
               P_Identifier_Declarations (Decls, Done, In_Spec);
4190
            end if;
4191
 
4192
         --  Ada2005: A subprogram declaration can start with "not" or
4193
         --  "overriding". In older versions, "overriding" is handled
4194
         --  like an identifier, with the appropriate messages.
4195
 
4196
         when Tok_Not =>
4197
            Check_Bad_Layout;
4198
            Append (P_Subprogram (Pf_Decl_Gins_Pbod_Rnam_Stub), Decls);
4199
            Done := False;
4200
 
4201
         when Tok_Overriding =>
4202
            Check_Bad_Layout;
4203
            Append (P_Subprogram (Pf_Decl_Gins_Pbod_Rnam_Stub), Decls);
4204
            Done := False;
4205
 
4206
         when Tok_Package =>
4207
            Check_Bad_Layout;
4208
            Append (P_Package (Pf_Decl_Gins_Pbod_Rnam_Stub), Decls);
4209
            Done := False;
4210
 
4211
         when Tok_Pragma =>
4212
            Append (P_Pragma, Decls);
4213
            Done := False;
4214
 
4215
         when Tok_Procedure =>
4216
            Check_Bad_Layout;
4217
            Append (P_Subprogram (Pf_Decl_Gins_Pbod_Rnam_Stub), Decls);
4218
            Done := False;
4219
 
4220
         when Tok_Protected =>
4221
            Check_Bad_Layout;
4222
            Scan; -- past PROTECTED
4223
            Append (P_Protected, Decls);
4224
            Done := False;
4225
 
4226
         when Tok_Subtype =>
4227
            Check_Bad_Layout;
4228
            Append (P_Subtype_Declaration, Decls);
4229
            Done := False;
4230
 
4231
         when Tok_Task =>
4232
            Check_Bad_Layout;
4233
            Scan; -- past TASK
4234
            Append (P_Task, Decls);
4235
            Done := False;
4236
 
4237
         when Tok_Type =>
4238
            Check_Bad_Layout;
4239
            Append (P_Type_Declaration, Decls);
4240
            Done := False;
4241
 
4242
         when Tok_Use =>
4243
            Check_Bad_Layout;
4244
            Append (P_Use_Clause, Decls);
4245
            Done := False;
4246
 
4247
         when Tok_With =>
4248
            Check_Bad_Layout;
4249
            Error_Msg_SC ("WITH can only appear in context clause");
4250
            raise Error_Resync;
4251
 
4252
         --  BEGIN terminates the scan of a sequence of declarations unless
4253
         --  there is a missing subprogram body, see section on handling
4254
         --  semicolon in place of IS. We only treat the begin as satisfying
4255
         --  the subprogram declaration if it falls in the expected column
4256
         --  or to its right.
4257
 
4258
         when Tok_Begin =>
4259
            if SIS_Entry_Active and then Start_Column >= SIS_Ecol then
4260
 
4261
               --  Here we have the case where a BEGIN is encountered during
4262
               --  declarations in a declarative part, or at the outer level,
4263
               --  and there is a subprogram declaration outstanding for which
4264
               --  no body has been supplied. This is the case where we assume
4265
               --  that the semicolon in the subprogram declaration should
4266
               --  really have been is. The active SIS entry describes the
4267
               --  subprogram declaration. On return the declaration has been
4268
               --  modified to become a body.
4269
 
4270
               declare
4271
                  Specification_Node : Node_Id;
4272
                  Decl_Node          : Node_Id;
4273
                  Body_Node          : Node_Id;
4274
 
4275
               begin
4276
                  --  First issue the error message. If we had a missing
4277
                  --  semicolon in the declaration, then change the message
4278
                  --  to <missing "is">
4279
 
4280
                  if SIS_Missing_Semicolon_Message /= No_Error_Msg then
4281
                     Change_Error_Text     -- Replace: "missing "";"" "
4282
                       (SIS_Missing_Semicolon_Message, "missing ""is""");
4283
 
4284
                  --  Otherwise we saved the semicolon position, so complain
4285
 
4286
                  else
4287
                     Error_Msg ("|"";"" should be IS", SIS_Semicolon_Sloc);
4288
                  end if;
4289
 
4290
                  --  The next job is to fix up any declarations that occurred
4291
                  --  between the procedure header and the BEGIN. These got
4292
                  --  chained to the outer declarative region (immediately
4293
                  --  after the procedure declaration) and they should be
4294
                  --  chained to the subprogram itself, which is a body
4295
                  --  rather than a spec.
4296
 
4297
                  Specification_Node := Specification (SIS_Declaration_Node);
4298
                  Change_Node (SIS_Declaration_Node, N_Subprogram_Body);
4299
                  Body_Node := SIS_Declaration_Node;
4300
                  Set_Specification (Body_Node, Specification_Node);
4301
                  Set_Declarations (Body_Node, New_List);
4302
 
4303
                  loop
4304
                     Decl_Node := Remove_Next (Body_Node);
4305
                     exit when Decl_Node = Empty;
4306
                     Append (Decl_Node, Declarations (Body_Node));
4307
                  end loop;
4308
 
4309
                  --  Now make the scope table entry for the Begin-End and
4310
                  --  scan it out
4311
 
4312
                  Push_Scope_Stack;
4313
                  Scope.Table (Scope.Last).Sloc := SIS_Sloc;
4314
                  Scope.Table (Scope.Last).Etyp := E_Name;
4315
                  Scope.Table (Scope.Last).Ecol := SIS_Ecol;
4316
                  Scope.Table (Scope.Last).Labl := SIS_Labl;
4317
                  Scope.Table (Scope.Last).Lreq := False;
4318
                  SIS_Entry_Active := False;
4319
                  Scan; -- past BEGIN
4320
                  Set_Handled_Statement_Sequence (Body_Node,
4321
                    P_Handled_Sequence_Of_Statements);
4322
                  End_Statements (Handled_Statement_Sequence (Body_Node));
4323
               end;
4324
 
4325
               Done := False;
4326
 
4327
            else
4328
               Done := True;
4329
            end if;
4330
 
4331
            --  Normally an END terminates the scan for basic declarative
4332
            --  items. The one exception is END RECORD, which is probably
4333
            --  left over from some other junk.
4334
 
4335
            when Tok_End =>
4336
               Save_Scan_State (Scan_State); -- at END
4337
               Scan; -- past END
4338
 
4339
               if Token = Tok_Record then
4340
                  Error_Msg_SP ("no RECORD for this `end record`!");
4341
                  Scan; -- past RECORD
4342
                  TF_Semicolon;
4343
 
4344
               else
4345
                  Restore_Scan_State (Scan_State); -- to END
4346
                  Done := True;
4347
               end if;
4348
 
4349
         --  The following tokens which can only be the start of a statement
4350
         --  are considered to end a declarative part (i.e. we have a missing
4351
         --  BEGIN situation). We are fairly conservative in making this
4352
         --  judgment, because it is a real mess to go into statement mode
4353
         --  prematurely in response to a junk declaration.
4354
 
4355
         when Tok_Abort     |
4356
              Tok_Accept    |
4357
              Tok_Declare   |
4358
              Tok_Delay     |
4359
              Tok_Exit      |
4360
              Tok_Goto      |
4361
              Tok_If        |
4362
              Tok_Loop      |
4363
              Tok_Null      |
4364
              Tok_Requeue   |
4365
              Tok_Select    |
4366
              Tok_While     =>
4367
 
4368
            --  But before we decide that it's a statement, let's check for
4369
            --  a reserved word misused as an identifier.
4370
 
4371
            if Is_Reserved_Identifier then
4372
               Save_Scan_State (Scan_State);
4373
               Scan; -- past the token
4374
 
4375
               --  If reserved identifier not followed by colon or comma, then
4376
               --  this is most likely an assignment statement to the bad id.
4377
 
4378
               if Token /= Tok_Colon and then Token /= Tok_Comma then
4379
                  Restore_Scan_State (Scan_State);
4380
                  Statement_When_Declaration_Expected (Decls, Done, In_Spec);
4381
                  return;
4382
 
4383
               --  Otherwise we have a declaration of the bad id
4384
 
4385
               else
4386
                  Restore_Scan_State (Scan_State);
4387
                  Scan_Reserved_Identifier (Force_Msg => True);
4388
                  P_Identifier_Declarations (Decls, Done, In_Spec);
4389
               end if;
4390
 
4391
            --  If not reserved identifier, then it's definitely a statement
4392
 
4393
            else
4394
               Statement_When_Declaration_Expected (Decls, Done, In_Spec);
4395
               return;
4396
            end if;
4397
 
4398
         --  The token RETURN may well also signal a missing BEGIN situation,
4399
         --  however, we never let it end the declarative part, because it may
4400
         --  also be part of a half-baked function declaration.
4401
 
4402
         when Tok_Return =>
4403
            Error_Msg_SC ("misplaced RETURN statement");
4404
            raise Error_Resync;
4405
 
4406
         --  PRIVATE definitely terminates the declarations in a spec,
4407
         --  and is an error in a body.
4408
 
4409
         when Tok_Private =>
4410
            if In_Spec then
4411
               Done := True;
4412
            else
4413
               Error_Msg_SC ("PRIVATE not allowed in body");
4414
               Scan; -- past PRIVATE
4415
            end if;
4416
 
4417
         --  An end of file definitely terminates the declarations!
4418
 
4419
         when Tok_EOF =>
4420
            Done := True;
4421
 
4422
         --  The remaining tokens do not end the scan, but cannot start a
4423
         --  valid declaration, so we signal an error and resynchronize.
4424
         --  But first check for misuse of a reserved identifier.
4425
 
4426
         when others =>
4427
 
4428
            --  Here we check for a reserved identifier
4429
 
4430
            if Is_Reserved_Identifier then
4431
               Save_Scan_State (Scan_State);
4432
               Scan; -- past the token
4433
 
4434
               if Token /= Tok_Colon and then Token /= Tok_Comma then
4435
                  Restore_Scan_State (Scan_State);
4436
                  Set_Declaration_Expected;
4437
                  raise Error_Resync;
4438
               else
4439
                  Restore_Scan_State (Scan_State);
4440
                  Scan_Reserved_Identifier (Force_Msg => True);
4441
                  Check_Bad_Layout;
4442
                  P_Identifier_Declarations (Decls, Done, In_Spec);
4443
               end if;
4444
 
4445
            else
4446
               Set_Declaration_Expected;
4447
               raise Error_Resync;
4448
            end if;
4449
      end case;
4450
 
4451
   --  To resynchronize after an error, we scan to the next semicolon and
4452
   --  return with Done = False, indicating that there may still be more
4453
   --  valid declarations to come.
4454
 
4455
   exception
4456
      when Error_Resync =>
4457
         Resync_Past_Semicolon;
4458
         Done := False;
4459
   end P_Declarative_Items;
4460
 
4461
   ----------------------------------
4462
   -- 3.11  Basic Declarative Item --
4463
   ----------------------------------
4464
 
4465
   --  BASIC_DECLARATIVE_ITEM ::=
4466
   --    BASIC_DECLARATION | REPRESENTATION_CLAUSE | USE_CLAUSE
4467
 
4468
   --  Scan zero or more basic declarative items
4469
 
4470
   --  Error recovery: cannot raise Error_Resync. If an error is detected, then
4471
   --  the scan pointer is repositioned past the next semicolon, and the scan
4472
   --  for declarative items continues.
4473
 
4474
   function P_Basic_Declarative_Items return List_Id is
4475
      Decl  : Node_Id;
4476
      Decls : List_Id;
4477
      Kind  : Node_Kind;
4478
      Done  : Boolean;
4479
 
4480
   begin
4481
      --  Indicate no bad declarations detected yet in the current context:
4482
      --  visible or private declarations of a package spec.
4483
 
4484
      Missing_Begin_Msg := No_Error_Msg;
4485
 
4486
      --  Get rid of active SIS entry from outer scope. This means we will
4487
      --  miss some nested cases, but it doesn't seem worth the effort. See
4488
      --  discussion in Par for further details
4489
 
4490
      SIS_Entry_Active := False;
4491
 
4492
      --  Loop to scan out declarations
4493
 
4494
      Decls := New_List;
4495
 
4496
      loop
4497
         P_Declarative_Items (Decls, Done, In_Spec => True);
4498
         exit when Done;
4499
      end loop;
4500
 
4501
      --  Get rid of active SIS entry. This is set only if we have scanned a
4502
      --  procedure declaration and have not found the body. We could give
4503
      --  an error message, but that really would be usurping the role of
4504
      --  semantic analysis (this really is a case of a missing body).
4505
 
4506
      SIS_Entry_Active := False;
4507
 
4508
      --  Test for assorted illegal declarations not diagnosed elsewhere
4509
 
4510
      Decl := First (Decls);
4511
 
4512
      while Present (Decl) loop
4513
         Kind := Nkind (Decl);
4514
 
4515
         --  Test for body scanned, not acceptable as basic decl item
4516
 
4517
         if Kind = N_Subprogram_Body or else
4518
            Kind = N_Package_Body or else
4519
            Kind = N_Task_Body or else
4520
            Kind = N_Protected_Body
4521
         then
4522
            Error_Msg
4523
              ("proper body not allowed in package spec", Sloc (Decl));
4524
 
4525
         --  Test for body stub scanned, not acceptable as basic decl item
4526
 
4527
         elsif Kind in N_Body_Stub then
4528
            Error_Msg
4529
              ("body stub not allowed in package spec", Sloc (Decl));
4530
 
4531
         elsif Kind = N_Assignment_Statement then
4532
            Error_Msg
4533
              ("assignment statement not allowed in package spec",
4534
                 Sloc (Decl));
4535
         end if;
4536
 
4537
         Next (Decl);
4538
      end loop;
4539
 
4540
      return Decls;
4541
   end P_Basic_Declarative_Items;
4542
 
4543
   ----------------
4544
   -- 3.11  Body --
4545
   ----------------
4546
 
4547
   --  For proper body, see below
4548
   --  For body stub, see 10.1.3
4549
 
4550
   -----------------------
4551
   -- 3.11  Proper Body --
4552
   -----------------------
4553
 
4554
   --  Subprogram body is parsed by P_Subprogram (6.1)
4555
   --  Package body is parsed by P_Package (7.1)
4556
   --  Task body is parsed by P_Task (9.1)
4557
   --  Protected body is parsed by P_Protected (9.4)
4558
 
4559
   ------------------------------
4560
   -- Set_Declaration_Expected --
4561
   ------------------------------
4562
 
4563
   procedure Set_Declaration_Expected is
4564
   begin
4565
      Error_Msg_SC ("declaration expected");
4566
 
4567
      if Missing_Begin_Msg = No_Error_Msg then
4568
         Missing_Begin_Msg := Get_Msg_Id;
4569
      end if;
4570
   end Set_Declaration_Expected;
4571
 
4572
   ----------------------
4573
   -- Skip_Declaration --
4574
   ----------------------
4575
 
4576
   procedure Skip_Declaration (S : List_Id) is
4577
      Dummy_Done : Boolean;
4578
      pragma Warnings (Off, Dummy_Done);
4579
   begin
4580
      P_Declarative_Items (S, Dummy_Done, False);
4581
   end Skip_Declaration;
4582
 
4583
   -----------------------------------------
4584
   -- Statement_When_Declaration_Expected --
4585
   -----------------------------------------
4586
 
4587
   procedure Statement_When_Declaration_Expected
4588
     (Decls   : List_Id;
4589
      Done    : out Boolean;
4590
      In_Spec : Boolean)
4591
   is
4592
   begin
4593
      --  Case of second occurrence of statement in one declaration sequence
4594
 
4595
      if Missing_Begin_Msg /= No_Error_Msg then
4596
 
4597
         --  In the procedure spec case, just ignore it, we only give one
4598
         --  message for the first occurrence, since otherwise we may get
4599
         --  horrible cascading if BODY was missing in the header line.
4600
 
4601
         if In_Spec then
4602
            null;
4603
 
4604
         --  In the declarative part case, take a second statement as a sure
4605
         --  sign that we really have a missing BEGIN, and end the declarative
4606
         --  part now. Note that the caller will fix up the first message to
4607
         --  say "missing BEGIN" so that's how the error will be signalled.
4608
 
4609
         else
4610
            Done := True;
4611
            return;
4612
         end if;
4613
 
4614
      --  Case of first occurrence of unexpected statement
4615
 
4616
      else
4617
         --  If we are in a package spec, then give message of statement
4618
         --  not allowed in package spec. This message never gets changed.
4619
 
4620
         if In_Spec then
4621
            Error_Msg_SC ("statement not allowed in package spec");
4622
 
4623
         --  If in declarative part, then we give the message complaining
4624
         --  about finding a statement when a declaration is expected. This
4625
         --  gets changed to a complaint about a missing BEGIN if we later
4626
         --  find that no BEGIN is present.
4627
 
4628
         else
4629
            Error_Msg_SC ("statement not allowed in declarative part");
4630
         end if;
4631
 
4632
         --  Capture message Id. This is used for two purposes, first to
4633
         --  stop multiple messages, see test above, and second, to allow
4634
         --  the replacement of the message in the declarative part case.
4635
 
4636
         Missing_Begin_Msg := Get_Msg_Id;
4637
      end if;
4638
 
4639
      --  In all cases except the case in which we decided to terminate the
4640
      --  declaration sequence on a second error, we scan out the statement
4641
      --  and append it to the list of declarations (note that the semantics
4642
      --  can handle statements in a declaration list so if we proceed to
4643
      --  call the semantic phase, all will be (reasonably) well!
4644
 
4645
      Append_List_To (Decls, P_Sequence_Of_Statements (SS_Unco));
4646
 
4647
      --  Done is set to False, since we want to continue the scan of
4648
      --  declarations, hoping that this statement was a temporary glitch.
4649
      --  If we indeed are now in the statement part (i.e. this was a missing
4650
      --  BEGIN, then it's not terrible, we will simply keep calling this
4651
      --  procedure to process the statements one by one, and then finally
4652
      --  hit the missing BEGIN, which will clean up the error message.
4653
 
4654
      Done := False;
4655
   end Statement_When_Declaration_Expected;
4656
 
4657
end Ch3;

powered by: WebSVN 2.1.0

© copyright 1999-2024 OpenCores.org, equivalent to Oliscience, all rights reserved. OpenCores®, registered trademark.