1------------------------------------------------------------------------------
2--                                                                          --
3--                         GNAT COMPILER COMPONENTS                         --
4--                                                                          --
5--                             P A R . P R A G                              --
6--                                                                          --
7--                                 B o d y                                  --
8--                                                                          --
9--          Copyright (C) 1992-2013, 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--  Generally the parser checks the basic syntax of pragmas, but does not
27--  do specialized syntax checks for individual pragmas, these are deferred
28--  to semantic analysis time (see unit Sem_Prag). There are some pragmas
29--  which require recognition and either partial or complete processing
30--  during parsing, and this unit performs this required processing.
31
32with Fname.UF; use Fname.UF;
33with Osint;    use Osint;
34with Rident;   use Rident;
35with Restrict; use Restrict;
36with Stringt;  use Stringt;
37with Stylesw;  use Stylesw;
38with Uintp;    use Uintp;
39with Uname;    use Uname;
40
41with System.WCh_Con; use System.WCh_Con;
42
43separate (Par)
44
45function Prag (Pragma_Node : Node_Id; Semi : Source_Ptr) return Node_Id is
46   Prag_Name   : constant Name_Id    := Pragma_Name (Pragma_Node);
47   Prag_Id     : constant Pragma_Id  := Get_Pragma_Id (Prag_Name);
48   Pragma_Sloc : constant Source_Ptr := Sloc (Pragma_Node);
49   Arg_Count   : Nat;
50   Arg_Node    : Node_Id;
51
52   -----------------------
53   -- Local Subprograms --
54   -----------------------
55
56   function Arg1 return Node_Id;
57   function Arg2 return Node_Id;
58   function Arg3 return Node_Id;
59   --  Obtain specified Pragma_Argument_Association. It is allowable to call
60   --  the routine for the argument one past the last present argument, but
61   --  that is the only case in which a non-present argument can be referenced.
62
63   procedure Check_Arg_Count (Required : Int);
64   --  Check argument count for pragma = Required. If not give error and raise
65   --  Error_Resync.
66
67   procedure Check_Arg_Is_String_Literal (Arg : Node_Id);
68   --  Check the expression of the specified argument to make sure that it
69   --  is a string literal. If not give error and raise Error_Resync.
70
71   procedure Check_Arg_Is_On_Or_Off (Arg : Node_Id);
72   --  Check the expression of the specified argument to make sure that it
73   --  is an identifier which is either ON or OFF, and if not, then issue
74   --  an error message and raise Error_Resync.
75
76   procedure Check_No_Identifier (Arg : Node_Id);
77   --  Checks that the given argument does not have an identifier. If
78   --  an identifier is present, then an error message is issued, and
79   --  Error_Resync is raised.
80
81   procedure Check_Optional_Identifier (Arg : Node_Id; Id : Name_Id);
82   --  Checks if the given argument has an identifier, and if so, requires
83   --  it to match the given identifier name. If there is a non-matching
84   --  identifier, then an error message is given and Error_Resync raised.
85
86   procedure Check_Required_Identifier (Arg : Node_Id; Id : Name_Id);
87   --  Same as Check_Optional_Identifier, except that the name is required
88   --  to be present and to match the given Id value.
89
90   procedure Process_Restrictions_Or_Restriction_Warnings;
91   --  Common processing for Restrictions and Restriction_Warnings pragmas.
92   --  For the most part, restrictions need not be processed at parse time,
93   --  since they only affect semantic processing. This routine handles the
94   --  exceptions as follows
95   --
96   --    No_Obsolescent_Features must be processed at parse time, since there
97   --    are some obsolescent features (e.g. character replacements) which are
98   --    handled at parse time.
99   --
100   --    SPARK must be processed at parse time, since this restriction controls
101   --    whether the scanner recognizes a spark HIDE directive formatted as an
102   --    Ada comment (and generates a Tok_SPARK_Hide token for the directive).
103   --
104   --    No_Dependence must be processed at parse time, since otherwise it gets
105   --    handled too late.
106   --
107   --  Note that we don't need to do full error checking for badly formed cases
108   --  of restrictions, since these will be caught during semantic analysis.
109
110   ----------
111   -- Arg1 --
112   ----------
113
114   function Arg1 return Node_Id is
115   begin
116      return First (Pragma_Argument_Associations (Pragma_Node));
117   end Arg1;
118
119   ----------
120   -- Arg2 --
121   ----------
122
123   function Arg2 return Node_Id is
124   begin
125      return Next (Arg1);
126   end Arg2;
127
128   ----------
129   -- Arg3 --
130   ----------
131
132   function Arg3 return Node_Id is
133   begin
134      return Next (Arg2);
135   end Arg3;
136
137   ---------------------
138   -- Check_Arg_Count --
139   ---------------------
140
141   procedure Check_Arg_Count (Required : Int) is
142   begin
143      if Arg_Count /= Required then
144         Error_Msg ("wrong number of arguments for pragma%", Pragma_Sloc);
145         raise Error_Resync;
146      end if;
147   end Check_Arg_Count;
148
149   ----------------------------
150   -- Check_Arg_Is_On_Or_Off --
151   ----------------------------
152
153   procedure Check_Arg_Is_On_Or_Off (Arg : Node_Id) is
154      Argx : constant Node_Id := Expression (Arg);
155
156   begin
157      if Nkind (Expression (Arg)) /= N_Identifier
158        or else not Nam_In (Chars (Argx), Name_On, Name_Off)
159      then
160         Error_Msg_Name_2 := Name_On;
161         Error_Msg_Name_3 := Name_Off;
162
163         Error_Msg ("argument for pragma% must be% or%", Sloc (Argx));
164         raise Error_Resync;
165      end if;
166   end Check_Arg_Is_On_Or_Off;
167
168   ---------------------------------
169   -- Check_Arg_Is_String_Literal --
170   ---------------------------------
171
172   procedure Check_Arg_Is_String_Literal (Arg : Node_Id) is
173   begin
174      if Nkind (Expression (Arg)) /= N_String_Literal then
175         Error_Msg
176           ("argument for pragma% must be string literal",
177             Sloc (Expression (Arg)));
178         raise Error_Resync;
179      end if;
180   end Check_Arg_Is_String_Literal;
181
182   -------------------------
183   -- Check_No_Identifier --
184   -------------------------
185
186   procedure Check_No_Identifier (Arg : Node_Id) is
187   begin
188      if Chars (Arg) /= No_Name then
189         Error_Msg_N ("pragma% does not permit named arguments", Arg);
190         raise Error_Resync;
191      end if;
192   end Check_No_Identifier;
193
194   -------------------------------
195   -- Check_Optional_Identifier --
196   -------------------------------
197
198   procedure Check_Optional_Identifier (Arg : Node_Id; Id : Name_Id) is
199   begin
200      if Present (Arg) and then Chars (Arg) /= No_Name then
201         if Chars (Arg) /= Id then
202            Error_Msg_Name_2 := Id;
203            Error_Msg_N ("pragma% argument expects identifier%", Arg);
204         end if;
205      end if;
206   end Check_Optional_Identifier;
207
208   -------------------------------
209   -- Check_Required_Identifier --
210   -------------------------------
211
212   procedure Check_Required_Identifier (Arg : Node_Id; Id : Name_Id) is
213   begin
214      if Chars (Arg) /= Id then
215         Error_Msg_Name_2 := Id;
216         Error_Msg_N ("pragma% argument must have identifier%", Arg);
217      end if;
218   end Check_Required_Identifier;
219
220   --------------------------------------------------
221   -- Process_Restrictions_Or_Restriction_Warnings --
222   --------------------------------------------------
223
224   procedure Process_Restrictions_Or_Restriction_Warnings is
225      Arg  : Node_Id;
226      Id   : Name_Id;
227      Expr : Node_Id;
228
229   begin
230      Arg := Arg1;
231      while Present (Arg) loop
232         Id := Chars (Arg);
233         Expr := Expression (Arg);
234
235         if Id = No_Name and then Nkind (Expr) = N_Identifier then
236            case Chars (Expr) is
237               when Name_No_Obsolescent_Features =>
238                  Set_Restriction (No_Obsolescent_Features, Pragma_Node);
239                  Restriction_Warnings (No_Obsolescent_Features) :=
240                    Prag_Id = Pragma_Restriction_Warnings;
241
242               when Name_SPARK | Name_SPARK_05 =>
243                  Set_Restriction (SPARK_05, Pragma_Node);
244                  Restriction_Warnings (SPARK_05) :=
245                    Prag_Id = Pragma_Restriction_Warnings;
246
247               when others =>
248                  null;
249            end case;
250
251         elsif Id = Name_No_Dependence then
252            Set_Restriction_No_Dependence
253              (Unit => Expr,
254               Warn => Prag_Id = Pragma_Restriction_Warnings
255                         or else Treat_Restrictions_As_Warnings);
256         end if;
257
258         Next (Arg);
259      end loop;
260   end Process_Restrictions_Or_Restriction_Warnings;
261
262--  Start of processing for Prag
263
264begin
265   Error_Msg_Name_1 := Prag_Name;
266
267   --  Ignore unrecognized pragma. We let Sem post the warning for this, since
268   --  it is a semantic error, not a syntactic one (we have already checked
269   --  the syntax for the unrecognized pragma as required by (RM 2.8(11)).
270
271   if Prag_Id = Unknown_Pragma then
272      return Pragma_Node;
273   end if;
274
275   --  Count number of arguments. This loop also checks if any of the arguments
276   --  are Error, indicating a syntax error as they were parsed. If so, we
277   --  simply return, because we get into trouble with cascaded errors if we
278   --  try to perform our error checks on junk arguments.
279
280   Arg_Count := 0;
281
282   if Present (Pragma_Argument_Associations (Pragma_Node)) then
283      Arg_Node := Arg1;
284      while Arg_Node /= Empty loop
285         Arg_Count := Arg_Count + 1;
286
287         if Expression (Arg_Node) = Error then
288            return Error;
289         end if;
290
291         Next (Arg_Node);
292      end loop;
293   end if;
294
295   --  Remaining processing is pragma dependent
296
297   case Prag_Id is
298
299      ------------
300      -- Ada_83 --
301      ------------
302
303      --  This pragma must be processed at parse time, since we want to set
304      --  the Ada version properly at parse time to recognize the appropriate
305      --  Ada version syntax.
306
307      when Pragma_Ada_83 =>
308         Ada_Version := Ada_83;
309         Ada_Version_Explicit := Ada_83;
310         Ada_Version_Pragma := Pragma_Node;
311
312      ------------
313      -- Ada_95 --
314      ------------
315
316      --  This pragma must be processed at parse time, since we want to set
317      --  the Ada version properly at parse time to recognize the appropriate
318      --  Ada version syntax.
319
320      when Pragma_Ada_95 =>
321         Ada_Version := Ada_95;
322         Ada_Version_Explicit := Ada_95;
323         Ada_Version_Pragma := Pragma_Node;
324
325      ---------------------
326      -- Ada_05/Ada_2005 --
327      ---------------------
328
329      --  These pragmas must be processed at parse time, since we want to set
330      --  the Ada version properly at parse time to recognize the appropriate
331      --  Ada version syntax. However, it is only the zero argument form that
332      --  must be processed at parse time.
333
334      when Pragma_Ada_05 | Pragma_Ada_2005 =>
335         if Arg_Count = 0 then
336            Ada_Version := Ada_2005;
337            Ada_Version_Explicit := Ada_2005;
338            Ada_Version_Pragma := Pragma_Node;
339         end if;
340
341      ---------------------
342      -- Ada_12/Ada_2012 --
343      ---------------------
344
345      --  These pragmas must be processed at parse time, since we want to set
346      --  the Ada version properly at parse time to recognize the appropriate
347      --  Ada version syntax. However, it is only the zero argument form that
348      --  must be processed at parse time.
349
350      when Pragma_Ada_12 | Pragma_Ada_2012 =>
351         if Arg_Count = 0 then
352            Ada_Version := Ada_2012;
353            Ada_Version_Explicit := Ada_2012;
354            Ada_Version_Pragma := Pragma_Node;
355         end if;
356
357      -----------
358      -- Debug --
359      -----------
360
361      --  pragma Debug ([boolean_EXPRESSION,] PROCEDURE_CALL_STATEMENT);
362
363      when Pragma_Debug =>
364         Check_No_Identifier (Arg1);
365
366         if Arg_Count = 2 then
367            Check_No_Identifier (Arg2);
368         else
369            Check_Arg_Count (1);
370         end if;
371
372      -------------------------------
373      -- Extensions_Allowed (GNAT) --
374      -------------------------------
375
376      --  pragma Extensions_Allowed (Off | On)
377
378      --  The processing for pragma Extensions_Allowed must be done at
379      --  parse time, since extensions mode may affect what is accepted.
380
381      when Pragma_Extensions_Allowed =>
382         Check_Arg_Count (1);
383         Check_No_Identifier (Arg1);
384         Check_Arg_Is_On_Or_Off (Arg1);
385
386         if Chars (Expression (Arg1)) = Name_On then
387            Extensions_Allowed := True;
388            Ada_Version := Ada_2012;
389         else
390            Extensions_Allowed := False;
391            Ada_Version := Ada_Version_Explicit;
392         end if;
393
394      ----------------
395      -- List (2.8) --
396      ----------------
397
398      --  pragma List (Off | On)
399
400      --  The processing for pragma List must be done at parse time,
401      --  since a listing can be generated in parse only mode.
402
403      when Pragma_List =>
404         Check_Arg_Count (1);
405         Check_No_Identifier (Arg1);
406         Check_Arg_Is_On_Or_Off (Arg1);
407
408         --  We unconditionally make a List_On entry for the pragma, so that
409         --  in the List (Off) case, the pragma will print even in a region
410         --  of code with listing turned off (this is required).
411
412         List_Pragmas.Increment_Last;
413         List_Pragmas.Table (List_Pragmas.Last) :=
414           (Ptyp => List_On, Ploc => Sloc (Pragma_Node));
415
416         --  Now generate the list off entry for pragma List (Off)
417
418         if Chars (Expression (Arg1)) = Name_Off then
419            List_Pragmas.Increment_Last;
420            List_Pragmas.Table (List_Pragmas.Last) :=
421              (Ptyp => List_Off, Ploc => Semi);
422         end if;
423
424      ----------------
425      -- Page (2.8) --
426      ----------------
427
428      --  pragma Page;
429
430      --  Processing for this pragma must be done at parse time, since a
431      --  listing can be generated in parse only mode with semantics off.
432
433      when Pragma_Page =>
434         Check_Arg_Count (0);
435         List_Pragmas.Increment_Last;
436         List_Pragmas.Table (List_Pragmas.Last) := (Page, Semi);
437
438      ------------------
439      -- Restrictions --
440      ------------------
441
442      --  pragma Restrictions (RESTRICTION {, RESTRICTION});
443
444      --  RESTRICTION ::=
445      --    restriction_IDENTIFIER
446      --  | restriction_parameter_IDENTIFIER => EXPRESSION
447
448      --  We process the case of No_Obsolescent_Features, since this has
449      --  a syntactic effect that we need to detect at parse time (the use
450      --  of replacement characters such as colon for pound sign).
451
452      when Pragma_Restrictions =>
453         Process_Restrictions_Or_Restriction_Warnings;
454
455      --------------------------
456      -- Restriction_Warnings --
457      --------------------------
458
459      --  pragma Restriction_Warnings (RESTRICTION {, RESTRICTION});
460
461      --  RESTRICTION ::=
462      --    restriction_IDENTIFIER
463      --  | restriction_parameter_IDENTIFIER => EXPRESSION
464
465      --  See above comment for pragma Restrictions
466
467      when Pragma_Restriction_Warnings =>
468         Process_Restrictions_Or_Restriction_Warnings;
469
470      ----------------------------------------------------------
471      -- Source_File_Name and Source_File_Name_Project (GNAT) --
472      ----------------------------------------------------------
473
474      --  These two pragmas have the same syntax and semantics.
475      --  There are five forms of these pragmas:
476
477      --  pragma Source_File_Name[_Project] (
478      --    [UNIT_NAME      =>] unit_NAME,
479      --     BODY_FILE_NAME =>  STRING_LITERAL
480      --    [, [INDEX =>] INTEGER_LITERAL]);
481
482      --  pragma Source_File_Name[_Project] (
483      --    [UNIT_NAME      =>] unit_NAME,
484      --     SPEC_FILE_NAME =>  STRING_LITERAL
485      --    [, [INDEX =>] INTEGER_LITERAL]);
486
487      --  pragma Source_File_Name[_Project] (
488      --     BODY_FILE_NAME  => STRING_LITERAL
489      --  [, DOT_REPLACEMENT => STRING_LITERAL]
490      --  [, CASING          => CASING_SPEC]);
491
492      --  pragma Source_File_Name[_Project] (
493      --     SPEC_FILE_NAME  => STRING_LITERAL
494      --  [, DOT_REPLACEMENT => STRING_LITERAL]
495      --  [, CASING          => CASING_SPEC]);
496
497      --  pragma Source_File_Name[_Project] (
498      --     SUBUNIT_FILE_NAME  => STRING_LITERAL
499      --  [, DOT_REPLACEMENT    => STRING_LITERAL]
500      --  [, CASING             => CASING_SPEC]);
501
502      --  CASING_SPEC ::= Uppercase | Lowercase | Mixedcase
503
504      --  Pragma Source_File_Name_Project (SFNP) is equivalent to pragma
505      --  Source_File_Name (SFN), however their usage is exclusive:
506      --  SFN can only be used when no project file is used, while
507      --  SFNP can only be used when a project file is used.
508
509      --  The Project Manager produces a configuration pragmas file that
510      --  is communicated to the compiler with -gnatec switch. This file
511      --  contains only SFNP pragmas (at least two for the default naming
512      --  scheme. As this configuration pragmas file is always the first
513      --  processed by the compiler, it prevents the use of pragmas SFN in
514      --  other config files when a project file is in use.
515
516      --  Note: we process this during parsing, since we need to have the
517      --  source file names set well before the semantic analysis starts,
518      --  since we load the spec and with'ed packages before analysis.
519
520      when Pragma_Source_File_Name | Pragma_Source_File_Name_Project =>
521         Source_File_Name : declare
522            Unam  : Unit_Name_Type;
523            Expr1 : Node_Id;
524            Pat   : String_Ptr;
525            Typ   : Character;
526            Dot   : String_Ptr;
527            Cas   : Casing_Type;
528            Nast  : Nat;
529            Expr  : Node_Id;
530            Index : Nat;
531
532            function Get_Fname (Arg : Node_Id) return File_Name_Type;
533            --  Process file name from unit name form of pragma
534
535            function Get_String_Argument (Arg : Node_Id) return String_Ptr;
536            --  Process string literal value from argument
537
538            procedure Process_Casing (Arg : Node_Id);
539            --  Process Casing argument of pattern form of pragma
540
541            procedure Process_Dot_Replacement (Arg : Node_Id);
542            --  Process Dot_Replacement argument of pattern form of pragma
543
544            ---------------
545            -- Get_Fname --
546            ---------------
547
548            function Get_Fname (Arg : Node_Id) return File_Name_Type is
549            begin
550               String_To_Name_Buffer (Strval (Expression (Arg)));
551
552               for J in 1 .. Name_Len loop
553                  if Is_Directory_Separator (Name_Buffer (J)) then
554                     Error_Msg
555                       ("directory separator character not allowed",
556                        Sloc (Expression (Arg)) + Source_Ptr (J));
557                  end if;
558               end loop;
559
560               return Name_Find;
561            end Get_Fname;
562
563            -------------------------
564            -- Get_String_Argument --
565            -------------------------
566
567            function Get_String_Argument (Arg : Node_Id) return String_Ptr is
568               Str : String_Id;
569
570            begin
571               if Nkind (Expression (Arg)) /= N_String_Literal
572                 and then
573                  Nkind (Expression (Arg)) /= N_Operator_Symbol
574               then
575                  Error_Msg_N
576                    ("argument for pragma% must be string literal", Arg);
577                  raise Error_Resync;
578               end if;
579
580               Str := Strval (Expression (Arg));
581
582               --  Check string has no wide chars
583
584               for J in 1 .. String_Length (Str) loop
585                  if Get_String_Char (Str, J) > 255 then
586                     Error_Msg
587                       ("wide character not allowed in pattern for pragma%",
588                        Sloc (Expression (Arg2)) + Text_Ptr (J) - 1);
589                  end if;
590               end loop;
591
592               --  Acquire string
593
594               String_To_Name_Buffer (Str);
595               return new String'(Name_Buffer (1 .. Name_Len));
596            end Get_String_Argument;
597
598            --------------------
599            -- Process_Casing --
600            --------------------
601
602            procedure Process_Casing (Arg : Node_Id) is
603               Expr : constant Node_Id := Expression (Arg);
604
605            begin
606               Check_Required_Identifier (Arg, Name_Casing);
607
608               if Nkind (Expr) = N_Identifier then
609                  if Chars (Expr) = Name_Lowercase then
610                     Cas := All_Lower_Case;
611                     return;
612                  elsif Chars (Expr) = Name_Uppercase then
613                     Cas := All_Upper_Case;
614                     return;
615                  elsif Chars (Expr) = Name_Mixedcase then
616                     Cas := Mixed_Case;
617                     return;
618                  end if;
619               end if;
620
621               Error_Msg_N
622                 ("Casing argument for pragma% must be " &
623                  "one of Mixedcase, Lowercase, Uppercase",
624                  Arg);
625            end Process_Casing;
626
627            -----------------------------
628            -- Process_Dot_Replacement --
629            -----------------------------
630
631            procedure Process_Dot_Replacement (Arg : Node_Id) is
632            begin
633               Check_Required_Identifier (Arg, Name_Dot_Replacement);
634               Dot := Get_String_Argument (Arg);
635            end Process_Dot_Replacement;
636
637         --  Start of processing for Source_File_Name and
638         --  Source_File_Name_Project pragmas.
639
640         begin
641            if Prag_Id = Pragma_Source_File_Name then
642               if Project_File_In_Use = In_Use then
643                  Error_Msg
644                    ("pragma Source_File_Name cannot be used " &
645                     "with a project file", Pragma_Sloc);
646
647               else
648                  Project_File_In_Use := Not_In_Use;
649               end if;
650
651            else
652               if Project_File_In_Use = Not_In_Use then
653                  Error_Msg
654                    ("pragma Source_File_Name_Project should only be used " &
655                     "with a project file", Pragma_Sloc);
656               else
657                  Project_File_In_Use := In_Use;
658               end if;
659            end if;
660
661            --  We permit from 1 to 3 arguments
662
663            if Arg_Count not in 1 .. 3 then
664               Check_Arg_Count (1);
665            end if;
666
667            Expr1 := Expression (Arg1);
668
669            --  If first argument is identifier or selected component, then
670            --  we have the specific file case of the Source_File_Name pragma,
671            --  and the first argument is a unit name.
672
673            if Nkind (Expr1) = N_Identifier
674              or else
675                (Nkind (Expr1) = N_Selected_Component
676                  and then
677                 Nkind (Selector_Name (Expr1)) = N_Identifier)
678            then
679               if Nkind (Expr1) = N_Identifier
680                 and then Chars (Expr1) = Name_System
681               then
682                  Error_Msg_N
683                    ("pragma Source_File_Name may not be used for System",
684                     Arg1);
685                  return Error;
686               end if;
687
688               --  Process index argument if present
689
690               if Arg_Count = 3 then
691                  Expr := Expression (Arg3);
692
693                  if Nkind (Expr) /= N_Integer_Literal
694                    or else not UI_Is_In_Int_Range (Intval (Expr))
695                    or else Intval (Expr) > 999
696                    or else Intval (Expr) <= 0
697                  then
698                     Error_Msg
699                       ("pragma% index must be integer literal" &
700                        " in range 1 .. 999", Sloc (Expr));
701                     raise Error_Resync;
702                  else
703                     Index := UI_To_Int (Intval (Expr));
704                  end if;
705
706               --  No index argument present
707
708               else
709                  Check_Arg_Count (2);
710                  Index := 0;
711               end if;
712
713               Check_Optional_Identifier (Arg1, Name_Unit_Name);
714               Unam := Get_Unit_Name (Expr1);
715
716               Check_Arg_Is_String_Literal (Arg2);
717
718               if Chars (Arg2) = Name_Spec_File_Name then
719                  Set_File_Name
720                    (Get_Spec_Name (Unam), Get_Fname (Arg2), Index);
721
722               elsif Chars (Arg2) = Name_Body_File_Name then
723                  Set_File_Name
724                    (Unam, Get_Fname (Arg2), Index);
725
726               else
727                  Error_Msg_N
728                    ("pragma% argument has incorrect identifier", Arg2);
729                  return Pragma_Node;
730               end if;
731
732            --  If the first argument is not an identifier, then we must have
733            --  the pattern form of the pragma, and the first argument must be
734            --  the pattern string with an appropriate name.
735
736            else
737               if Chars (Arg1) = Name_Spec_File_Name then
738                  Typ := 's';
739
740               elsif Chars (Arg1) = Name_Body_File_Name then
741                  Typ := 'b';
742
743               elsif Chars (Arg1) = Name_Subunit_File_Name then
744                  Typ := 'u';
745
746               elsif Chars (Arg1) = Name_Unit_Name then
747                  Error_Msg_N
748                    ("Unit_Name parameter for pragma% must be an identifier",
749                     Arg1);
750                  raise Error_Resync;
751
752               else
753                  Error_Msg_N
754                    ("pragma% argument has incorrect identifier", Arg1);
755                  raise Error_Resync;
756               end if;
757
758               Pat := Get_String_Argument (Arg1);
759
760               --  Check pattern has exactly one asterisk
761
762               Nast := 0;
763               for J in Pat'Range loop
764                  if Pat (J) = '*' then
765                     Nast := Nast + 1;
766                  end if;
767               end loop;
768
769               if Nast /= 1 then
770                  Error_Msg_N
771                    ("file name pattern must have exactly one * character",
772                     Arg1);
773                  return Pragma_Node;
774               end if;
775
776               --  Set defaults for Casing and Dot_Separator parameters
777
778               Cas := All_Lower_Case;
779               Dot := new String'(".");
780
781               --  Process second and third arguments if present
782
783               if Arg_Count > 1 then
784                  if Chars (Arg2) = Name_Casing then
785                     Process_Casing (Arg2);
786
787                     if Arg_Count = 3 then
788                        Process_Dot_Replacement (Arg3);
789                     end if;
790
791                  else
792                     Process_Dot_Replacement (Arg2);
793
794                     if Arg_Count = 3 then
795                        Process_Casing (Arg3);
796                     end if;
797                  end if;
798               end if;
799
800               Set_File_Name_Pattern (Pat, Typ, Dot, Cas);
801            end if;
802         end Source_File_Name;
803
804      -----------------------------
805      -- Source_Reference (GNAT) --
806      -----------------------------
807
808      --  pragma Source_Reference
809      --    (INTEGER_LITERAL [, STRING_LITERAL] );
810
811      --  Processing for this pragma must be done at parse time, since error
812      --  messages needing the proper line numbers can be generated in parse
813      --  only mode with semantic checking turned off, and indeed we usually
814      --  turn off semantic checking anyway if any parse errors are found.
815
816      when Pragma_Source_Reference => Source_Reference : declare
817         Fname : File_Name_Type;
818
819      begin
820         if Arg_Count /= 1 then
821            Check_Arg_Count (2);
822            Check_No_Identifier (Arg2);
823         end if;
824
825         --  Check that this is first line of file. We skip this test if
826         --  we are in syntax check only mode, since we may be dealing with
827         --  multiple compilation units.
828
829         if Get_Physical_Line_Number (Pragma_Sloc) /= 1
830           and then Num_SRef_Pragmas (Current_Source_File) = 0
831           and then Operating_Mode /= Check_Syntax
832         then
833            Error_Msg -- CODEFIX
834              ("first % pragma must be first line of file", Pragma_Sloc);
835            raise Error_Resync;
836         end if;
837
838         Check_No_Identifier (Arg1);
839
840         if Arg_Count = 1 then
841            if Num_SRef_Pragmas (Current_Source_File) = 0 then
842               Error_Msg
843                 ("file name required for first % pragma in file",
844                  Pragma_Sloc);
845               raise Error_Resync;
846            else
847               Fname := No_File;
848            end if;
849
850         --  File name present
851
852         else
853            Check_Arg_Is_String_Literal (Arg2);
854            String_To_Name_Buffer (Strval (Expression (Arg2)));
855            Fname := Name_Find;
856
857            if Num_SRef_Pragmas (Current_Source_File) > 0 then
858               if Fname /= Full_Ref_Name (Current_Source_File) then
859                  Error_Msg
860                    ("file name must be same in all % pragmas", Pragma_Sloc);
861                  raise Error_Resync;
862               end if;
863            end if;
864         end if;
865
866         if Nkind (Expression (Arg1)) /= N_Integer_Literal then
867            Error_Msg
868              ("argument for pragma% must be integer literal",
869                Sloc (Expression (Arg1)));
870            raise Error_Resync;
871
872         --  OK, this source reference pragma is effective, however, we
873         --  ignore it if it is not in the first unit in the multiple unit
874         --  case. This is because the only purpose in this case is to
875         --  provide source pragmas for subsequent use by gnatchop.
876
877         else
878            if Num_Library_Units = 1 then
879               Register_Source_Ref_Pragma
880                 (Fname,
881                  Strip_Directory (Fname),
882                  UI_To_Int (Intval (Expression (Arg1))),
883                  Get_Physical_Line_Number (Pragma_Sloc) + 1);
884            end if;
885         end if;
886      end Source_Reference;
887
888      -------------------------
889      -- Style_Checks (GNAT) --
890      -------------------------
891
892      --  pragma Style_Checks (On | Off | ALL_CHECKS | STRING_LITERAL);
893
894      --  This is processed by the parser since some of the style
895      --  checks take place during source scanning and parsing.
896
897      when Pragma_Style_Checks => Style_Checks : declare
898         A  : Node_Id;
899         S  : String_Id;
900         C  : Char_Code;
901         OK : Boolean := True;
902
903      begin
904         --  Two argument case is only for semantics
905
906         if Arg_Count = 2 then
907            null;
908
909         else
910            Check_Arg_Count (1);
911            Check_No_Identifier (Arg1);
912            A := Expression (Arg1);
913
914            if Nkind (A) = N_String_Literal then
915               S := Strval (A);
916
917               declare
918                  Slen    : constant Natural := Natural (String_Length (S));
919                  Options : String (1 .. Slen);
920                  J       : Natural;
921                  Ptr     : Natural;
922
923               begin
924                  J := 1;
925                  loop
926                     C := Get_String_Char (S, Int (J));
927
928                     if not In_Character_Range (C) then
929                        OK := False;
930                        Ptr := J;
931                        exit;
932
933                     else
934                        Options (J) := Get_Character (C);
935                     end if;
936
937                     if J = Slen then
938                        if not Ignore_Style_Checks_Pragmas then
939                           Set_Style_Check_Options (Options, OK, Ptr);
940                        end if;
941
942                        exit;
943
944                     else
945                        J := J + 1;
946                     end if;
947                  end loop;
948
949                  if not OK then
950                     Error_Msg
951                       (Style_Msg_Buf (1 .. Style_Msg_Len),
952                        Sloc (Expression (Arg1)) + Source_Ptr (Ptr));
953                     raise Error_Resync;
954                  end if;
955               end;
956
957            elsif Nkind (A) /= N_Identifier then
958               OK := False;
959
960            elsif Chars (A) = Name_All_Checks then
961               if not Ignore_Style_Checks_Pragmas then
962                  if GNAT_Mode then
963                     Stylesw.Set_GNAT_Style_Check_Options;
964                  else
965                     Stylesw.Set_Default_Style_Check_Options;
966                  end if;
967               end if;
968
969            elsif Chars (A) = Name_On then
970               if not Ignore_Style_Checks_Pragmas then
971                  Style_Check := True;
972               end if;
973
974            elsif Chars (A) = Name_Off then
975               if not Ignore_Style_Checks_Pragmas then
976                  Style_Check := False;
977               end if;
978
979            else
980               OK := False;
981            end if;
982
983            if not OK then
984               Error_Msg ("incorrect argument for pragma%", Sloc (A));
985               raise Error_Resync;
986            end if;
987         end if;
988      end Style_Checks;
989
990      -------------------------
991      -- Suppress_All (GNAT) --
992      -------------------------
993
994      --  pragma Suppress_All
995
996      --  This is a rather odd pragma, because other compilers allow it in
997      --  strange places. DEC allows it at the end of units, and Rational
998      --  allows it as a program unit pragma, when it would be more natural
999      --  if it were a configuration pragma.
1000
1001      --  Since the reason we provide this pragma is for compatibility with
1002      --  these other compilers, we want to accommodate these strange placement
1003      --  rules, and the easiest thing is simply to allow it anywhere in a
1004      --  unit. If this pragma appears anywhere within a unit, then the effect
1005      --  is as though a pragma Suppress (All_Checks) had appeared as the first
1006      --  line of the current file, i.e. as the first configuration pragma in
1007      --  the current unit.
1008
1009      --  To get this effect, we set the flag Has_Pragma_Suppress_All in the
1010      --  compilation unit node for the current source file then in the last
1011      --  stage of parsing a file, if this flag is set, we materialize the
1012      --  Suppress (All_Checks) pragma, marked as not coming from Source.
1013
1014      when Pragma_Suppress_All =>
1015         Set_Has_Pragma_Suppress_All (Cunit (Current_Source_Unit));
1016
1017      ---------------------
1018      -- Warnings (GNAT) --
1019      ---------------------
1020
1021      --  pragma Warnings (On | Off [,REASON]);
1022      --  pragma Warnings (On | Off, LOCAL_NAME [,REASON]);
1023      --  pragma Warnings (static_string_EXPRESSION [,REASON]);
1024      --  pragma Warnings (On | Off, static_string_EXPRESSION [,REASON]);
1025
1026      --  The one argument ON/OFF case is processed by the parser, since it may
1027      --  control parser warnings as well as semantic warnings, and in any case
1028      --  we want to be absolutely sure that the range in the warnings table is
1029      --  set well before any semantic analysis is performed. Note that we
1030      --  ignore this pragma if debug flag -gnatd.i is set.
1031
1032      --  Also note that the "one argument" case may have two arguments if the
1033      --  second one is a reason argument.
1034
1035      when Pragma_Warnings =>
1036         if not Debug_Flag_Dot_I
1037           and then (Arg_Count = 1
1038                      or else (Arg_Count = 2
1039                                and then Chars (Arg2) = Name_Reason))
1040         then
1041            Check_No_Identifier (Arg1);
1042
1043            declare
1044               Argx : constant Node_Id := Expression (Arg1);
1045
1046               function Get_Reason return String_Id;
1047               --  Analyzes Reason argument and returns corresponding String_Id
1048               --  value, or null if there is no Reason argument, or if the
1049               --  argument is not of the required form.
1050
1051               ----------------
1052               -- Get_Reason --
1053               ----------------
1054
1055               function Get_Reason return String_Id is
1056               begin
1057                  if Arg_Count = 1 then
1058                     return Null_String_Id;
1059                  else
1060                     Start_String;
1061                     Get_Reason_String (Expression (Arg2));
1062                     return End_String;
1063                  end if;
1064               end Get_Reason;
1065
1066            begin
1067               if Nkind (Argx) = N_Identifier then
1068                  if Chars (Argx) = Name_On then
1069                     Set_Warnings_Mode_On (Pragma_Sloc);
1070                  elsif Chars (Argx) = Name_Off then
1071                     Set_Warnings_Mode_Off (Pragma_Sloc, Get_Reason);
1072                  end if;
1073               end if;
1074            end;
1075         end if;
1076
1077      -----------------------------
1078      -- Wide_Character_Encoding --
1079      -----------------------------
1080
1081      --  pragma Wide_Character_Encoding (IDENTIFIER | CHARACTER_LITERAL);
1082
1083      --  This is processed by the parser, since the scanner is affected
1084
1085      when Pragma_Wide_Character_Encoding => Wide_Character_Encoding : declare
1086         A : Node_Id;
1087
1088      begin
1089         Check_Arg_Count (1);
1090         Check_No_Identifier (Arg1);
1091         A := Expression (Arg1);
1092
1093         if Nkind (A) = N_Identifier then
1094            Get_Name_String (Chars (A));
1095            Wide_Character_Encoding_Method :=
1096              Get_WC_Encoding_Method (Name_Buffer (1 .. Name_Len));
1097
1098         elsif Nkind (A) = N_Character_Literal then
1099            declare
1100               R : constant Char_Code :=
1101                     Char_Code (UI_To_Int (Char_Literal_Value (A)));
1102            begin
1103               if In_Character_Range (R) then
1104                  Wide_Character_Encoding_Method :=
1105                    Get_WC_Encoding_Method (Get_Character (R));
1106               else
1107                  raise Constraint_Error;
1108               end if;
1109            end;
1110
1111         else
1112            raise Constraint_Error;
1113         end if;
1114
1115         Upper_Half_Encoding :=
1116           Wide_Character_Encoding_Method in
1117             WC_Upper_Half_Encoding_Method;
1118
1119      exception
1120         when Constraint_Error =>
1121            Error_Msg_N ("invalid argument for pragma%", Arg1);
1122      end Wide_Character_Encoding;
1123
1124      -----------------------
1125      -- All Other Pragmas --
1126      -----------------------
1127
1128      --  For all other pragmas, checking and processing is handled
1129      --  entirely in Sem_Prag, and no further checking is done by Par.
1130
1131      when Pragma_Abort_Defer                    |
1132           Pragma_Abstract_State                 |
1133           Pragma_Async_Readers                  |
1134           Pragma_Async_Writers                  |
1135           Pragma_Assertion_Policy               |
1136           Pragma_Assume                         |
1137           Pragma_Assume_No_Invalid_Values       |
1138           Pragma_AST_Entry                      |
1139           Pragma_All_Calls_Remote               |
1140           Pragma_Allow_Integer_Address          |
1141           Pragma_Annotate                       |
1142           Pragma_Assert                         |
1143           Pragma_Assert_And_Cut                 |
1144           Pragma_Asynchronous                   |
1145           Pragma_Atomic                         |
1146           Pragma_Atomic_Components              |
1147           Pragma_Attach_Handler                 |
1148           Pragma_Attribute_Definition           |
1149           Pragma_Check                          |
1150           Pragma_Check_Float_Overflow           |
1151           Pragma_Check_Name                     |
1152           Pragma_Check_Policy                   |
1153           Pragma_CIL_Constructor                |
1154           Pragma_Compile_Time_Error             |
1155           Pragma_Compile_Time_Warning           |
1156           Pragma_Compiler_Unit                  |
1157           Pragma_Compiler_Unit_Warning          |
1158           Pragma_Contract_Cases                 |
1159           Pragma_Convention_Identifier          |
1160           Pragma_CPP_Class                      |
1161           Pragma_CPP_Constructor                |
1162           Pragma_CPP_Virtual                    |
1163           Pragma_CPP_Vtable                     |
1164           Pragma_CPU                            |
1165           Pragma_C_Pass_By_Copy                 |
1166           Pragma_Comment                        |
1167           Pragma_Common_Object                  |
1168           Pragma_Complete_Representation        |
1169           Pragma_Complex_Representation         |
1170           Pragma_Component_Alignment            |
1171           Pragma_Controlled                     |
1172           Pragma_Convention                     |
1173           Pragma_Debug_Policy                   |
1174           Pragma_Depends                        |
1175           Pragma_Detect_Blocking                |
1176           Pragma_Default_Storage_Pool           |
1177           Pragma_Disable_Atomic_Synchronization |
1178           Pragma_Discard_Names                  |
1179           Pragma_Dispatching_Domain             |
1180           Pragma_Effective_Reads                |
1181           Pragma_Effective_Writes               |
1182           Pragma_Eliminate                      |
1183           Pragma_Elaborate                      |
1184           Pragma_Elaborate_All                  |
1185           Pragma_Elaborate_Body                 |
1186           Pragma_Elaboration_Checks             |
1187           Pragma_Enable_Atomic_Synchronization  |
1188           Pragma_Export                         |
1189           Pragma_Export_Exception               |
1190           Pragma_Export_Function                |
1191           Pragma_Export_Object                  |
1192           Pragma_Export_Procedure               |
1193           Pragma_Export_Value                   |
1194           Pragma_Export_Valued_Procedure        |
1195           Pragma_Extend_System                  |
1196           Pragma_External                       |
1197           Pragma_External_Name_Casing           |
1198           Pragma_Favor_Top_Level                |
1199           Pragma_Fast_Math                      |
1200           Pragma_Finalize_Storage_Only          |
1201           Pragma_Float_Representation           |
1202           Pragma_Global                         |
1203           Pragma_Ident                          |
1204           Pragma_Implementation_Defined         |
1205           Pragma_Implemented                    |
1206           Pragma_Implicit_Packing               |
1207           Pragma_Import                         |
1208           Pragma_Import_Exception               |
1209           Pragma_Import_Function                |
1210           Pragma_Import_Object                  |
1211           Pragma_Import_Procedure               |
1212           Pragma_Import_Valued_Procedure        |
1213           Pragma_Independent                    |
1214           Pragma_Independent_Components         |
1215           Pragma_Initial_Condition              |
1216           Pragma_Initialize_Scalars             |
1217           Pragma_Initializes                    |
1218           Pragma_Inline                         |
1219           Pragma_Inline_Always                  |
1220           Pragma_Inline_Generic                 |
1221           Pragma_Inspection_Point               |
1222           Pragma_Interface                      |
1223           Pragma_Interface_Name                 |
1224           Pragma_Interrupt_Handler              |
1225           Pragma_Interrupt_State                |
1226           Pragma_Interrupt_Priority             |
1227           Pragma_Invariant                      |
1228           Pragma_Java_Constructor               |
1229           Pragma_Java_Interface                 |
1230           Pragma_Keep_Names                     |
1231           Pragma_License                        |
1232           Pragma_Link_With                      |
1233           Pragma_Linker_Alias                   |
1234           Pragma_Linker_Constructor             |
1235           Pragma_Linker_Destructor              |
1236           Pragma_Linker_Options                 |
1237           Pragma_Linker_Section                 |
1238           Pragma_Lock_Free                      |
1239           Pragma_Locking_Policy                 |
1240           Pragma_Long_Float                     |
1241           Pragma_Loop_Invariant                 |
1242           Pragma_Loop_Optimize                  |
1243           Pragma_Loop_Variant                   |
1244           Pragma_Machine_Attribute              |
1245           Pragma_Main                           |
1246           Pragma_Main_Storage                   |
1247           Pragma_Memory_Size                    |
1248           Pragma_No_Body                        |
1249           Pragma_No_Inline                      |
1250           Pragma_No_Return                      |
1251           Pragma_No_Run_Time                    |
1252           Pragma_No_Strict_Aliasing             |
1253           Pragma_Normalize_Scalars              |
1254           Pragma_Obsolescent                    |
1255           Pragma_Ordered                        |
1256           Pragma_Optimize                       |
1257           Pragma_Optimize_Alignment             |
1258           Pragma_Overflow_Mode                  |
1259           Pragma_Overriding_Renamings           |
1260           Pragma_Pack                           |
1261           Pragma_Part_Of                        |
1262           Pragma_Partition_Elaboration_Policy   |
1263           Pragma_Passive                        |
1264           Pragma_Preelaborable_Initialization   |
1265           Pragma_Polling                        |
1266           Pragma_Persistent_BSS                 |
1267           Pragma_Post                           |
1268           Pragma_Postcondition                  |
1269           Pragma_Post_Class                     |
1270           Pragma_Pre                            |
1271           Pragma_Precondition                   |
1272           Pragma_Predicate                      |
1273           Pragma_Preelaborate                   |
1274           Pragma_Preelaborate_05                |
1275           Pragma_Pre_Class                      |
1276           Pragma_Priority                       |
1277           Pragma_Priority_Specific_Dispatching  |
1278           Pragma_Profile                        |
1279           Pragma_Profile_Warnings               |
1280           Pragma_Propagate_Exceptions           |
1281           Pragma_Provide_Shift_Operators        |
1282           Pragma_Psect_Object                   |
1283           Pragma_Pure                           |
1284           Pragma_Pure_05                        |
1285           Pragma_Pure_12                        |
1286           Pragma_Pure_Function                  |
1287           Pragma_Queuing_Policy                 |
1288           Pragma_Refined_Depends                |
1289           Pragma_Refined_Global                 |
1290           Pragma_Refined_Post                   |
1291           Pragma_Refined_State                  |
1292           Pragma_Relative_Deadline              |
1293           Pragma_Remote_Access_Type             |
1294           Pragma_Remote_Call_Interface          |
1295           Pragma_Remote_Types                   |
1296           Pragma_Restricted_Run_Time            |
1297           Pragma_Rational                       |
1298           Pragma_Ravenscar                      |
1299           Pragma_Reviewable                     |
1300           Pragma_Share_Generic                  |
1301           Pragma_Shared                         |
1302           Pragma_Shared_Passive                 |
1303           Pragma_Short_Circuit_And_Or           |
1304           Pragma_Short_Descriptors              |
1305           Pragma_Simple_Storage_Pool_Type       |
1306           Pragma_SPARK_Mode                     |
1307           Pragma_Storage_Size                   |
1308           Pragma_Storage_Unit                   |
1309           Pragma_Static_Elaboration_Desired     |
1310           Pragma_Stream_Convert                 |
1311           Pragma_Subtitle                       |
1312           Pragma_Suppress                       |
1313           Pragma_Suppress_Debug_Info            |
1314           Pragma_Suppress_Exception_Locations   |
1315           Pragma_Suppress_Initialization        |
1316           Pragma_System_Name                    |
1317           Pragma_Task_Dispatching_Policy        |
1318           Pragma_Task_Info                      |
1319           Pragma_Task_Name                      |
1320           Pragma_Task_Storage                   |
1321           Pragma_Test_Case                      |
1322           Pragma_Thread_Local_Storage           |
1323           Pragma_Time_Slice                     |
1324           Pragma_Title                          |
1325           Pragma_Type_Invariant                 |
1326           Pragma_Type_Invariant_Class           |
1327           Pragma_Unchecked_Union                |
1328           Pragma_Unimplemented_Unit             |
1329           Pragma_Universal_Aliasing             |
1330           Pragma_Universal_Data                 |
1331           Pragma_Unmodified                     |
1332           Pragma_Unreferenced                   |
1333           Pragma_Unreferenced_Objects           |
1334           Pragma_Unreserve_All_Interrupts       |
1335           Pragma_Unsuppress                     |
1336           Pragma_Use_VADS_Size                  |
1337           Pragma_Volatile                       |
1338           Pragma_Volatile_Components            |
1339           Pragma_Warning_As_Error               |
1340           Pragma_Weak_External                  |
1341           Pragma_Validity_Checks                =>
1342         null;
1343
1344      --------------------
1345      -- Unknown_Pragma --
1346      --------------------
1347
1348      --  Should be impossible, since we excluded this case earlier on
1349
1350      when Unknown_Pragma =>
1351         raise Program_Error;
1352
1353   end case;
1354
1355   return Pragma_Node;
1356
1357   --------------------
1358   -- Error Handling --
1359   --------------------
1360
1361exception
1362   when Error_Resync =>
1363      return Error;
1364
1365end Prag;
1366