1------------------------------------------------------------------------------
2--                                                                          --
3--                         GNAT COMPILER COMPONENTS                         --
4--                                                                          --
5--                               E R R O U T                                --
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--  Warning: Error messages can be generated during Gigi processing by direct
27--  calls to error message routines, so it is essential that the processing
28--  in this body be consistent with the requirements for the Gigi processing
29--  environment, and that in particular, no disallowed table expansion is
30--  allowed to occur.
31
32with Atree;    use Atree;
33with Casing;   use Casing;
34with Csets;    use Csets;
35with Debug;    use Debug;
36with Einfo;    use Einfo;
37with Erroutc;  use Erroutc;
38with Fname;    use Fname;
39with Gnatvsn;  use Gnatvsn;
40with Hostparm; use Hostparm;
41with Lib;      use Lib;
42with Opt;      use Opt;
43with Nlists;   use Nlists;
44with Output;   use Output;
45with Scans;    use Scans;
46with Sem_Aux;  use Sem_Aux;
47with Sinput;   use Sinput;
48with Sinfo;    use Sinfo;
49with Snames;   use Snames;
50with Stand;    use Stand;
51with Stylesw;  use Stylesw;
52with Uname;    use Uname;
53
54package body Errout is
55
56   Errors_Must_Be_Ignored : Boolean := False;
57   --  Set to True by procedure Set_Ignore_Errors (True), when calls to error
58   --  message procedures should be ignored (when parsing irrelevant text in
59   --  sources being preprocessed).
60
61   Finalize_Called : Boolean := False;
62   --  Set True if the Finalize routine has been called
63
64   Warn_On_Instance : Boolean;
65   --  Flag set true for warning message to be posted on instance
66
67   ------------------------------------
68   -- Table of Non-Instance Messages --
69   ------------------------------------
70
71   --  This table contains an entry for every error message processed by the
72   --  Error_Msg routine that is not posted on generic (or inlined) instance.
73   --  As explained in further detail in the Error_Msg procedure body, this
74   --  table is used to avoid posting redundant messages on instances.
75
76   type NIM_Record is record
77      Msg : String_Ptr;
78      Loc : Source_Ptr;
79   end record;
80   --  Type used to store text and location of one message
81
82   package Non_Instance_Msgs is new Table.Table (
83     Table_Component_Type => NIM_Record,
84     Table_Index_Type     => Int,
85     Table_Low_Bound      => 1,
86     Table_Initial        => 100,
87     Table_Increment      => 100,
88     Table_Name           => "Non_Instance_Msgs");
89
90   -----------------------
91   -- Local Subprograms --
92   -----------------------
93
94   procedure Error_Msg_Internal
95     (Msg      : String;
96      Sptr     : Source_Ptr;
97      Optr     : Source_Ptr;
98      Msg_Cont : Boolean);
99   --  This is the low level routine used to post messages after dealing with
100   --  the issue of messages placed on instantiations (which get broken up
101   --  into separate calls in Error_Msg). Sptr is the location on which the
102   --  flag will be placed in the output. In the case where the flag is on
103   --  the template, this points directly to the template, not to one of the
104   --  instantiation copies of the template. Optr is the original location
105   --  used to flag the error, and this may indeed point to an instantiation
106   --  copy. So typically we can see Optr pointing to the template location
107   --  in an instantiation copy when Sptr points to the source location of
108   --  the actual instantiation (i.e the line with the new). Msg_Cont is
109   --  set true if this is a continuation message.
110
111   function No_Warnings (N : Node_Or_Entity_Id) return Boolean;
112   --  Determines if warnings should be suppressed for the given node
113
114   function OK_Node (N : Node_Id) return Boolean;
115   --  Determines if a node is an OK node to place an error message on (return
116   --  True) or if the error message should be suppressed (return False). A
117   --  message is suppressed if the node already has an error posted on it,
118   --  or if it refers to an Etype that has an error posted on it, or if
119   --  it references an Entity that has an error posted on it.
120
121   procedure Output_Source_Line
122     (L     : Physical_Line_Number;
123      Sfile : Source_File_Index;
124      Errs  : Boolean);
125   --  Outputs text of source line L, in file S, together with preceding line
126   --  number, as described above for Output_Line_Number. The Errs parameter
127   --  indicates if there are errors attached to the line, which forces
128   --  listing on, even in the presence of pragma List (Off).
129
130   procedure Set_Msg_Insertion_Column;
131   --  Handle column number insertion (@ insertion character)
132
133   procedure Set_Msg_Insertion_Node;
134   --  Handle node (name from node) insertion (& insertion character)
135
136   procedure Set_Msg_Insertion_Type_Reference (Flag : Source_Ptr);
137   --  Handle type reference (right brace insertion character). Flag is the
138   --  location of the flag, which is provided for the internal call to
139   --  Set_Msg_Insertion_Line_Number,
140
141   procedure Set_Msg_Insertion_Unit_Name (Suffix : Boolean := True);
142   --  Handle unit name insertion ($ insertion character). Depending on Boolean
143   --  parameter Suffix, (spec) or (body) is appended after the unit name.
144
145   procedure Set_Msg_Node (Node : Node_Id);
146   --  Add the sequence of characters for the name associated with the given
147   --  node to the current message. For N_Designator, N_Selected_Component,
148   --  N_Defining_Program_Unit_Name, and N_Expanded_Name, the Prefix is
149   --  included as well.
150
151   procedure Set_Msg_Text (Text : String; Flag : Source_Ptr);
152   --  Add a sequence of characters to the current message. The characters may
153   --  be one of the special insertion characters (see documentation in spec).
154   --  Flag is the location at which the error is to be posted, which is used
155   --  to determine whether or not the # insertion needs a file name. The
156   --  variables Msg_Buffer are set on return Msglen.
157
158   procedure Set_Posted (N : Node_Id);
159   --  Sets the Error_Posted flag on the given node, and all its parents
160   --  that are subexpressions and then on the parent non-subexpression
161   --  construct that contains the original expression (this reduces the
162   --  number of cascaded messages). Note that this call only has an effect
163   --  for a serious error. For a non-serious error, it has no effect.
164
165   procedure Set_Qualification (N : Nat; E : Entity_Id);
166   --  Outputs up to N levels of qualification for the given entity. For
167   --  example, the entity A.B.C.D will output B.C. if N = 2.
168
169   function Special_Msg_Delete
170     (Msg : String;
171      N   : Node_Or_Entity_Id;
172      E   : Node_Or_Entity_Id) return Boolean;
173   --  This function is called from Error_Msg_NEL, passing the message Msg,
174   --  node N on which the error is to be posted, and the entity or node E
175   --  to be used for an & insertion in the message if any. The job of this
176   --  procedure is to test for certain cascaded messages that we would like
177   --  to suppress. If the message is to be suppressed then we return True.
178   --  If the message should be generated (the normal case) False is returned.
179
180   procedure Unwind_Internal_Type (Ent : in out Entity_Id);
181   --  This procedure is given an entity id for an internal type, i.e. a type
182   --  with an internal name. It unwinds the type to try to get to something
183   --  reasonably printable, generating prefixes like "subtype of", "access
184   --  to", etc along the way in the buffer. The value in Ent on return is the
185   --  final name to be printed. Hopefully this is not an internal name, but in
186   --  some internal name cases, it is an internal name, and has to be printed
187   --  anyway (although in this case the message has been killed if possible).
188   --  The global variable Class_Flag is set to True if the resulting entity
189   --  should have 'Class appended to its name (see Add_Class procedure), and
190   --  is otherwise unchanged.
191
192   procedure VMS_Convert;
193   --  This procedure has no effect if called when the host is not OpenVMS. If
194   --  the host is indeed OpenVMS, then the error message stored in Msg_Buffer
195   --  is scanned for appearances of switch names which need converting to
196   --  corresponding VMS qualifier names. See Gnames/Vnames table in Errout
197   --  spec for precise definition of the conversion that is performed by this
198   --  routine in OpenVMS mode.
199
200   -----------------------
201   -- Change_Error_Text --
202   -----------------------
203
204   procedure Change_Error_Text (Error_Id : Error_Msg_Id; New_Msg : String) is
205      Save_Next : Error_Msg_Id;
206      Err_Id    : Error_Msg_Id := Error_Id;
207
208   begin
209      Set_Msg_Text (New_Msg, Errors.Table (Error_Id).Sptr);
210      Errors.Table (Error_Id).Text := new String'(Msg_Buffer (1 .. Msglen));
211
212      --  If in immediate error message mode, output modified error message now
213      --  This is just a bit tricky, because we want to output just a single
214      --  message, and the messages we modified is already linked in. We solve
215      --  this by temporarily resetting its forward pointer to empty.
216
217      if Debug_Flag_OO then
218         Save_Next := Errors.Table (Error_Id).Next;
219         Errors.Table (Error_Id).Next := No_Error_Msg;
220         Write_Eol;
221         Output_Source_Line
222           (Errors.Table (Error_Id).Line, Errors.Table (Error_Id).Sfile, True);
223         Output_Error_Msgs (Err_Id);
224         Errors.Table (Error_Id).Next := Save_Next;
225      end if;
226   end Change_Error_Text;
227
228   ------------------------
229   -- Compilation_Errors --
230   ------------------------
231
232   function Compilation_Errors return Boolean is
233   begin
234      if not Finalize_Called then
235         raise Program_Error;
236      else
237         return Erroutc.Compilation_Errors;
238      end if;
239   end Compilation_Errors;
240
241   ---------------
242   -- Error_Msg --
243   ---------------
244
245   --  Error_Msg posts a flag at the given location, except that if the
246   --  Flag_Location points within a generic template and corresponds to an
247   --  instantiation of this generic template, then the actual message will be
248   --  posted on the generic instantiation, along with additional messages
249   --  referencing the generic declaration.
250
251   procedure Error_Msg (Msg : String; Flag_Location : Source_Ptr) is
252      Sindex : Source_File_Index;
253      --  Source index for flag location
254
255      Orig_Loc : Source_Ptr;
256      --  Original location of Flag_Location (i.e. location in original
257      --  template in instantiation case, otherwise unchanged).
258
259   begin
260      --  It is a fatal error to issue an error message when scanning from the
261      --  internal source buffer (see Sinput for further documentation)
262
263      pragma Assert (Sinput.Source /= Internal_Source_Ptr);
264
265      --  Return if all errors are to be ignored
266
267      if Errors_Must_Be_Ignored then
268         return;
269      end if;
270
271      --  If we already have messages, and we are trying to place a message at
272      --  No_Location or in package Standard, then just ignore the attempt
273      --  since we assume that what is happening is some cascaded junk. Note
274      --  that this is safe in the sense that proceeding will surely bomb.
275
276      if Flag_Location < First_Source_Ptr
277        and then Total_Errors_Detected > 0
278      then
279         return;
280      end if;
281
282      --  Start of processing for new message
283
284      Sindex := Get_Source_File_Index (Flag_Location);
285      Test_Style_Warning_Serious_Unconditional_Msg (Msg);
286      Orig_Loc := Original_Location (Flag_Location);
287
288      --  If the current location is in an instantiation, the issue arises of
289      --  whether to post the message on the template or the instantiation.
290
291      --  The way we decide is to see if we have posted the same message on
292      --  the template when we compiled the template (the template is always
293      --  compiled before any instantiations). For this purpose, we use a
294      --  separate table of messages. The reason we do this is twofold:
295
296      --     First, the messages can get changed by various processing
297      --     including the insertion of tokens etc, making it hard to
298      --     do the comparison.
299
300      --     Second, we will suppress a warning on a template if it is not in
301      --     the current extended source unit. That's reasonable and means we
302      --     don't want the warning on the instantiation here either, but it
303      --     does mean that the main error table would not in any case include
304      --     the message.
305
306      if Flag_Location = Orig_Loc then
307         Non_Instance_Msgs.Append ((new String'(Msg), Flag_Location));
308         Warn_On_Instance := False;
309
310      --  Here we have an instance message
311
312      else
313         --  Delete if debug flag off, and this message duplicates a message
314         --  already posted on the corresponding template
315
316         if not Debug_Flag_GG then
317            for J in Non_Instance_Msgs.First .. Non_Instance_Msgs.Last loop
318               if Msg = Non_Instance_Msgs.Table (J).Msg.all
319                 and then Non_Instance_Msgs.Table (J).Loc = Orig_Loc
320               then
321                  return;
322               end if;
323            end loop;
324         end if;
325
326         --  No duplicate, so error/warning will be posted on instance
327
328         Warn_On_Instance := Is_Warning_Msg;
329      end if;
330
331      --  Ignore warning message that is suppressed for this location. Note
332      --  that style checks are not considered warning messages for this
333      --  purpose.
334
335      if Is_Warning_Msg
336        and then Warnings_Suppressed (Orig_Loc) /= No_String
337      then
338         return;
339
340      --  For style messages, check too many messages so far
341
342      elsif Is_Style_Msg
343        and then Maximum_Messages /= 0
344        and then Warnings_Detected >= Maximum_Messages
345      then
346         return;
347      end if;
348
349      --  The idea at this stage is that we have two kinds of messages
350
351      --  First, we have those messages that are to be placed as requested at
352      --  Flag_Location. This includes messages that have nothing to do with
353      --  generics, and also messages placed on generic templates that reflect
354      --  an error in the template itself. For such messages we simply call
355      --  Error_Msg_Internal to place the message in the requested location.
356
357      if Instantiation (Sindex) = No_Location then
358         Error_Msg_Internal (Msg, Flag_Location, Flag_Location, False);
359         return;
360      end if;
361
362      --  If we are trying to flag an error in an instantiation, we may have
363      --  a generic contract violation. What we generate in this case is:
364
365      --     instantiation error at ...
366      --     original error message
367
368      --  or
369
370      --     warning: in instantiation at
371      --     warning: original warning message
372
373      --  All these messages are posted at the location of the top level
374      --  instantiation. If there are nested instantiations, then the
375      --  instantiation error message can be repeated, pointing to each
376      --  of the relevant instantiations.
377
378      --  Note: the instantiation mechanism is also shared for inlining of
379      --  subprogram bodies when front end inlining is done. In this case the
380      --  messages have the form:
381
382      --     in inlined body at ...
383      --     original error message
384
385      --  or
386
387      --     warning: in inlined body at
388      --     warning: original warning message
389
390      --  OK, here we have an instantiation error, and we need to generate the
391      --  error on the instantiation, rather than on the template.
392
393      declare
394         Actual_Error_Loc : Source_Ptr;
395         --  Location of outer level instantiation in instantiation case, or
396         --  just a copy of Flag_Location in the normal case. This is the
397         --  location where all error messages will actually be posted.
398
399         Save_Error_Msg_Sloc : constant Source_Ptr := Error_Msg_Sloc;
400         --  Save possible location set for caller's message. We need to use
401         --  Error_Msg_Sloc for the location of the instantiation error but we
402         --  have to preserve a possible original value.
403
404         X : Source_File_Index;
405
406         Msg_Cont_Status : Boolean;
407         --  Used to label continuation lines in instantiation case with
408         --  proper Msg_Cont status.
409
410      begin
411         --  Loop to find highest level instantiation, where all error
412         --  messages will be placed.
413
414         X := Sindex;
415         loop
416            Actual_Error_Loc := Instantiation (X);
417            X := Get_Source_File_Index (Actual_Error_Loc);
418            exit when Instantiation (X) = No_Location;
419         end loop;
420
421         --  Since we are generating the messages at the instantiation point in
422         --  any case, we do not want the references to the bad lines in the
423         --  instance to be annotated with the location of the instantiation.
424
425         Suppress_Instance_Location := True;
426         Msg_Cont_Status := False;
427
428         --  Loop to generate instantiation messages
429
430         Error_Msg_Sloc := Flag_Location;
431         X := Get_Source_File_Index (Flag_Location);
432         while Instantiation (X) /= No_Location loop
433
434            --  Suppress instantiation message on continuation lines
435
436            if Msg (Msg'First) /= '\' then
437
438               --  Case of inlined body
439
440               if Inlined_Body (X) then
441                  if Is_Warning_Msg or else Is_Style_Msg then
442                     Error_Msg_Internal
443                       ("?in inlined body #",
444                        Actual_Error_Loc, Flag_Location, Msg_Cont_Status);
445                  else
446                     Error_Msg_Internal
447                       ("error in inlined body #",
448                        Actual_Error_Loc, Flag_Location, Msg_Cont_Status);
449                  end if;
450
451               --  Case of generic instantiation
452
453               else
454                  if Is_Warning_Msg or else Is_Style_Msg then
455                     Error_Msg_Internal
456                       ("?in instantiation #",
457                        Actual_Error_Loc, Flag_Location, Msg_Cont_Status);
458                  else
459                     Error_Msg_Internal
460                       ("instantiation error #",
461                        Actual_Error_Loc, Flag_Location, Msg_Cont_Status);
462                  end if;
463               end if;
464            end if;
465
466            Error_Msg_Sloc := Instantiation (X);
467            X := Get_Source_File_Index (Error_Msg_Sloc);
468            Msg_Cont_Status := True;
469         end loop;
470
471         Suppress_Instance_Location := False;
472         Error_Msg_Sloc := Save_Error_Msg_Sloc;
473
474         --  Here we output the original message on the outer instantiation
475
476         Error_Msg_Internal
477           (Msg, Actual_Error_Loc, Flag_Location, Msg_Cont_Status);
478      end;
479   end Error_Msg;
480
481   --------------------------------
482   -- Error_Msg_Ada_2012_Feature --
483   --------------------------------
484
485   procedure Error_Msg_Ada_2012_Feature (Feature : String; Loc : Source_Ptr) is
486   begin
487      if Ada_Version < Ada_2012 then
488         Error_Msg (Feature & " is an Ada 2012 feature", Loc);
489
490         if No (Ada_Version_Pragma) then
491            Error_Msg ("\unit must be compiled with -gnat2012 switch", Loc);
492         else
493            Error_Msg_Sloc := Sloc (Ada_Version_Pragma);
494            Error_Msg ("\incompatible with Ada version set#", Loc);
495         end if;
496      end if;
497   end Error_Msg_Ada_2012_Feature;
498
499   ------------------
500   -- Error_Msg_AP --
501   ------------------
502
503   procedure Error_Msg_AP (Msg : String) is
504      S1 : Source_Ptr;
505      C  : Character;
506
507   begin
508      --  If we had saved the Scan_Ptr value after scanning the previous
509      --  token, then we would have exactly the right place for putting
510      --  the flag immediately at hand. However, that would add at least
511      --  two instructions to a Scan call *just* to service the possibility
512      --  of an Error_Msg_AP call. So instead we reconstruct that value.
513
514      --  We have two possibilities, start with Prev_Token_Ptr and skip over
515      --  the current token, which is made harder by the possibility that this
516      --  token may be in error, or start with Token_Ptr and work backwards.
517      --  We used to take the second approach, but it's hard because of
518      --  comments, and harder still because things that look like comments
519      --  can appear inside strings. So now we take the first approach.
520
521      --  Note: in the case where there is no previous token, Prev_Token_Ptr
522      --  is set to Source_First, which is a reasonable position for the
523      --  error flag in this situation.
524
525      S1 := Prev_Token_Ptr;
526      C := Source (S1);
527
528      --  If the previous token is a string literal, we need a special approach
529      --  since there may be white space inside the literal and we don't want
530      --  to stop on that white space.
531
532      --  Note: since this is an error recovery issue anyway, it is not worth
533      --  worrying about special UTF_32 line terminator characters here.
534
535      if Prev_Token = Tok_String_Literal then
536         loop
537            S1 := S1 + 1;
538
539            if Source (S1) = C then
540               S1 := S1 + 1;
541               exit when Source (S1) /= C;
542            elsif Source (S1) in Line_Terminator then
543               exit;
544            end if;
545         end loop;
546
547      --  Character literal also needs special handling
548
549      elsif Prev_Token = Tok_Char_Literal then
550         S1 := S1 + 3;
551
552      --  Otherwise we search forward for the end of the current token, marked
553      --  by a line terminator, white space, a comment symbol or if we bump
554      --  into the following token (i.e. the current token).
555
556      --  Again, it is not worth worrying about UTF_32 special line terminator
557      --  characters in this context, since this is only for error recovery.
558
559      else
560         while Source (S1) not in Line_Terminator
561           and then Source (S1) /= ' '
562           and then Source (S1) /= ASCII.HT
563           and then (Source (S1) /= '-' or else Source (S1 + 1) /= '-')
564           and then S1 /= Token_Ptr
565         loop
566            S1 := S1 + 1;
567         end loop;
568      end if;
569
570      --  S1 is now set to the location for the flag
571
572      Error_Msg (Msg, S1);
573   end Error_Msg_AP;
574
575   ------------------
576   -- Error_Msg_BC --
577   ------------------
578
579   procedure Error_Msg_BC (Msg : String) is
580   begin
581      --  If we are at end of file, post the flag after the previous token
582
583      if Token = Tok_EOF then
584         Error_Msg_AP (Msg);
585
586      --  If we are at start of file, post the flag at the current token
587
588      elsif Token_Ptr = Source_First (Current_Source_File) then
589         Error_Msg_SC (Msg);
590
591      --  If the character before the current token is a space or a horizontal
592      --  tab, then we place the flag on this character (in the case of a tab
593      --  we would really like to place it in the "last" character of the tab
594      --  space, but that it too much trouble to worry about).
595
596      elsif Source (Token_Ptr - 1) = ' '
597         or else Source (Token_Ptr - 1) = ASCII.HT
598      then
599         Error_Msg (Msg, Token_Ptr - 1);
600
601      --  If there is no space or tab before the current token, then there is
602      --  no room to place the flag before the token, so we place it on the
603      --  token instead (this happens for example at the start of a line).
604
605      else
606         Error_Msg (Msg, Token_Ptr);
607      end if;
608   end Error_Msg_BC;
609
610   -------------------
611   -- Error_Msg_CRT --
612   -------------------
613
614   procedure Error_Msg_CRT (Feature : String; N : Node_Id) is
615      CNRT : constant String := " not allowed in no run time mode";
616      CCRT : constant String := " not supported by configuration>";
617
618      S : String (1 .. Feature'Length + 1 + CCRT'Length);
619      L : Natural;
620
621   begin
622      S (1) := '|';
623      S (2 .. Feature'Length + 1) := Feature;
624      L := Feature'Length + 2;
625
626      if No_Run_Time_Mode then
627         S (L .. L + CNRT'Length - 1) := CNRT;
628         L := L + CNRT'Length - 1;
629
630      else pragma Assert (Configurable_Run_Time_Mode);
631         S (L .. L + CCRT'Length - 1) := CCRT;
632         L := L + CCRT'Length - 1;
633      end if;
634
635      Error_Msg_N (S (1 .. L), N);
636      Configurable_Run_Time_Violations := Configurable_Run_Time_Violations + 1;
637   end Error_Msg_CRT;
638
639   ------------------
640   -- Error_Msg_PT --
641   ------------------
642
643   procedure Error_Msg_PT (Typ : Node_Id; Subp : Node_Id) is
644   begin
645      Error_Msg_NE
646        ("first formal of & must be of mode `OUT`, `IN OUT` or " &
647         "access-to-variable", Typ, Subp);
648      Error_Msg_N
649        ("\in order to be overridden by protected procedure or entry " &
650         "(RM 9.4(11.9/2))", Typ);
651   end Error_Msg_PT;
652
653   -----------------
654   -- Error_Msg_F --
655   -----------------
656
657   procedure Error_Msg_F (Msg : String; N : Node_Id) is
658   begin
659      Error_Msg_NEL (Msg, N, N, Sloc (First_Node (N)));
660   end Error_Msg_F;
661
662   ------------------
663   -- Error_Msg_FE --
664   ------------------
665
666   procedure Error_Msg_FE
667     (Msg : String;
668      N   : Node_Id;
669      E   : Node_Or_Entity_Id)
670   is
671   begin
672      Error_Msg_NEL (Msg, N, E, Sloc (First_Node (N)));
673   end Error_Msg_FE;
674
675   ------------------------
676   -- Error_Msg_Internal --
677   ------------------------
678
679   procedure Error_Msg_Internal
680     (Msg      : String;
681      Sptr     : Source_Ptr;
682      Optr     : Source_Ptr;
683      Msg_Cont : Boolean)
684   is
685      Next_Msg : Error_Msg_Id;
686      --  Pointer to next message at insertion point
687
688      Prev_Msg : Error_Msg_Id;
689      --  Pointer to previous message at insertion point
690
691      Temp_Msg : Error_Msg_Id;
692
693      Warn_Err : Boolean;
694      --  Set if warning to be treated as error
695
696      procedure Handle_Serious_Error;
697      --  Internal procedure to do all error message handling for a serious
698      --  error message, other than bumping the error counts and arranging
699      --  for the message to be output.
700
701      --------------------------
702      -- Handle_Serious_Error --
703      --------------------------
704
705      procedure Handle_Serious_Error is
706      begin
707         --  Turn off code generation if not done already
708
709         if Operating_Mode = Generate_Code then
710            Operating_Mode := Check_Semantics;
711            Expander_Active := False;
712         end if;
713
714         --  Set the fatal error flag in the unit table unless we are in
715         --  Try_Semantics mode. This stops the semantics from being performed
716         --  if we find a serious error. This is skipped if we are currently
717         --  dealing with the configuration pragma file.
718
719         if not Try_Semantics and then Current_Source_Unit /= No_Unit then
720            Set_Fatal_Error (Get_Source_Unit (Sptr));
721         end if;
722      end Handle_Serious_Error;
723
724   --  Start of processing for Error_Msg_Internal
725
726   begin
727      if Raise_Exception_On_Error /= 0 then
728         raise Error_Msg_Exception;
729      end if;
730
731      Continuation := Msg_Cont;
732      Continuation_New_Line := False;
733      Suppress_Message := False;
734      Kill_Message := False;
735      Warning_Msg_Char := ' ';
736      Set_Msg_Text (Msg, Sptr);
737
738      --  Kill continuation if parent message killed
739
740      if Continuation and Last_Killed then
741         return;
742      end if;
743
744      --  Return without doing anything if message is suppressed
745
746      if Suppress_Message
747        and then not All_Errors_Mode
748        and then not Is_Warning_Msg
749        and then not Is_Unconditional_Msg
750      then
751         if not Continuation then
752            Last_Killed := True;
753         end if;
754
755         return;
756      end if;
757
758      --  Return without doing anything if message is killed and this is not
759      --  the first error message. The philosophy is that if we get a weird
760      --  error message and we already have had a message, then we hope the
761      --  weird message is a junk cascaded message
762
763      if Kill_Message
764        and then not All_Errors_Mode
765        and then Total_Errors_Detected /= 0
766      then
767         if not Continuation then
768            Last_Killed := True;
769         end if;
770
771         return;
772      end if;
773
774      --  Special check for warning message to see if it should be output
775
776      if Is_Warning_Msg then
777
778         --  Immediate return if warning message and warnings are suppressed
779
780         if Warnings_Suppressed (Optr) /= No_String
781              or else
782            Warnings_Suppressed (Sptr) /= No_String
783         then
784            Cur_Msg := No_Error_Msg;
785            return;
786         end if;
787
788         --  If the flag location is in the main extended source unit then for
789         --  sure we want the warning since it definitely belongs
790
791         if In_Extended_Main_Source_Unit (Sptr) then
792            null;
793
794         --  If the main unit has not been read yet. the warning must be on
795         --  a configuration file: gnat.adc or user-defined. This means we
796         --  are not parsing the main unit yet, so skip following checks.
797
798         elsif No (Cunit (Main_Unit)) then
799            null;
800
801         --  If the flag location is not in the main extended source unit, then
802         --  we want to eliminate the warning, unless it is in the extended
803         --  main code unit and we want warnings on the instance.
804
805         elsif In_Extended_Main_Code_Unit (Sptr) and then Warn_On_Instance then
806            null;
807
808         --  Keep warning if debug flag G set
809
810         elsif Debug_Flag_GG then
811            null;
812
813         --  Keep warning if message text contains !!
814
815         elsif Has_Double_Exclam then
816            null;
817
818         --  Here is where we delete a warning from a with'ed unit
819
820         else
821            Cur_Msg := No_Error_Msg;
822
823            if not Continuation then
824               Last_Killed := True;
825            end if;
826
827            return;
828         end if;
829      end if;
830
831      --  If message is to be ignored in special ignore message mode, this is
832      --  where we do this special processing, bypassing message output.
833
834      if Ignore_Errors_Enable > 0 then
835         if Is_Serious_Error then
836            Handle_Serious_Error;
837         end if;
838
839         return;
840      end if;
841
842      --  If error message line length set, and this is a continuation message
843      --  then all we do is to append the text to the text of the last message
844      --  with a comma space separator (eliminating a possible (style) or
845      --  info prefix).
846
847      if Error_Msg_Line_Length /= 0 and then Continuation then
848         Cur_Msg := Errors.Last;
849
850         declare
851            Oldm : String_Ptr := Errors.Table (Cur_Msg).Text;
852            Newm : String (1 .. Oldm'Last + 2 + Msglen);
853            Newl : Natural;
854            M    : Natural;
855
856         begin
857            --  First copy old message to new one and free it
858
859            Newm (Oldm'Range) := Oldm.all;
860            Newl := Oldm'Length;
861            Free (Oldm);
862
863            --  Remove (style) or info: at start of message
864
865            if Msglen > 8 and then Msg_Buffer (1 .. 8) = "(style) " then
866               M := 9;
867
868            elsif Msglen > 6 and then Msg_Buffer (1 .. 6) = "info: " then
869               M := 7;
870
871            else
872               M := 1;
873            end if;
874
875            --  Now deal with separation between messages. Normally this is
876            --  simply comma space, but there are some special cases.
877
878            --  If continuation new line, then put actual NL character in msg
879
880            if Continuation_New_Line then
881               Newl := Newl + 1;
882               Newm (Newl) := ASCII.LF;
883
884            --  If continuation message is enclosed in parentheses, then
885            --  special treatment (don't need a comma, and we want to combine
886            --  successive parenthetical remarks into a single one with
887            --  separating commas).
888
889            elsif Msg_Buffer (M) = '(' and then Msg_Buffer (Msglen) = ')' then
890
891               --  Case where existing message ends in right paren, remove
892               --  and separate parenthetical remarks with a comma.
893
894               if Newm (Newl) = ')' then
895                  Newm (Newl) := ',';
896                  Msg_Buffer (M) := ' ';
897
898               --  Case where we are adding new parenthetical comment
899
900               else
901                  Newl := Newl + 1;
902                  Newm (Newl) := ' ';
903               end if;
904
905            --  Case where continuation not in parens and no new line
906
907            else
908               Newm (Newl + 1 .. Newl + 2) := ", ";
909               Newl := Newl + 2;
910            end if;
911
912            --  Append new message
913
914            Newm (Newl + 1 .. Newl + Msglen - M + 1) :=
915              Msg_Buffer (M .. Msglen);
916            Newl := Newl + Msglen - M + 1;
917            Errors.Table (Cur_Msg).Text := new String'(Newm (1 .. Newl));
918
919            --  Update warning msg flag and message doc char if needed
920
921            if Is_Warning_Msg then
922               if not Errors.Table (Cur_Msg).Warn then
923                  Errors.Table (Cur_Msg).Warn := True;
924                  Errors.Table (Cur_Msg).Warn_Chr := Warning_Msg_Char;
925
926               elsif Warning_Msg_Char /= ' ' then
927                  Errors.Table (Cur_Msg).Warn_Chr := Warning_Msg_Char;
928               end if;
929            end if;
930         end;
931
932         return;
933      end if;
934
935      --  Here we build a new error object
936
937      Errors.Append
938        ((Text     => new String'(Msg_Buffer (1 .. Msglen)),
939          Next     => No_Error_Msg,
940          Prev     => No_Error_Msg,
941          Sptr     => Sptr,
942          Optr     => Optr,
943          Sfile    => Get_Source_File_Index (Sptr),
944          Line     => Get_Physical_Line_Number (Sptr),
945          Col      => Get_Column_Number (Sptr),
946          Warn     => Is_Warning_Msg,
947          Warn_Err => False, -- reset below
948          Warn_Chr => Warning_Msg_Char,
949          Style    => Is_Style_Msg,
950          Serious  => Is_Serious_Error,
951          Uncond   => Is_Unconditional_Msg,
952          Msg_Cont => Continuation,
953          Deleted  => False));
954      Cur_Msg := Errors.Last;
955
956      --  Test if warning to be treated as error
957
958      Warn_Err :=
959        Is_Warning_Msg
960          and then (Warning_Treated_As_Error (Msg_Buffer (1 .. Msglen))
961                      or else
962                    Warning_Treated_As_Error (Get_Warning_Tag (Cur_Msg)));
963
964      --  Propagate Warn_Err to this message and preceding continuations
965
966      for J in reverse 1 .. Errors.Last loop
967         Errors.Table (J).Warn_Err := Warn_Err;
968         exit when not Errors.Table (J).Msg_Cont;
969      end loop;
970
971      --  If immediate errors mode set, output error message now. Also output
972      --  now if the -d1 debug flag is set (so node number message comes out
973      --  just before actual error message)
974
975      if Debug_Flag_OO or else Debug_Flag_1 then
976         Write_Eol;
977         Output_Source_Line
978           (Errors.Table (Cur_Msg).Line, Errors.Table (Cur_Msg).Sfile, True);
979         Temp_Msg := Cur_Msg;
980         Output_Error_Msgs (Temp_Msg);
981
982      --  If not in immediate errors mode, then we insert the message in the
983      --  error chain for later output by Finalize. The messages are sorted
984      --  first by unit (main unit comes first), and within a unit by source
985      --  location (earlier flag location first in the chain).
986
987      else
988         --  First a quick check, does this belong at the very end of the chain
989         --  of error messages. This saves a lot of time in the normal case if
990         --  there are lots of messages.
991
992         if Last_Error_Msg /= No_Error_Msg
993           and then Errors.Table (Cur_Msg).Sfile =
994                    Errors.Table (Last_Error_Msg).Sfile
995           and then (Sptr > Errors.Table (Last_Error_Msg).Sptr
996                       or else
997                          (Sptr = Errors.Table (Last_Error_Msg).Sptr
998                             and then
999                               Optr > Errors.Table (Last_Error_Msg).Optr))
1000         then
1001            Prev_Msg := Last_Error_Msg;
1002            Next_Msg := No_Error_Msg;
1003
1004         --  Otherwise do a full sequential search for the insertion point
1005
1006         else
1007            Prev_Msg := No_Error_Msg;
1008            Next_Msg := First_Error_Msg;
1009            while Next_Msg /= No_Error_Msg loop
1010               exit when
1011                 Errors.Table (Cur_Msg).Sfile < Errors.Table (Next_Msg).Sfile;
1012
1013               if Errors.Table (Cur_Msg).Sfile =
1014                    Errors.Table (Next_Msg).Sfile
1015               then
1016                  exit when Sptr < Errors.Table (Next_Msg).Sptr
1017                              or else
1018                                (Sptr = Errors.Table (Next_Msg).Sptr
1019                                   and then
1020                                 Optr < Errors.Table (Next_Msg).Optr);
1021               end if;
1022
1023               Prev_Msg := Next_Msg;
1024               Next_Msg := Errors.Table (Next_Msg).Next;
1025            end loop;
1026         end if;
1027
1028         --  Now we insert the new message in the error chain. The insertion
1029         --  point for the message is after Prev_Msg and before Next_Msg.
1030
1031         --  The possible insertion point for the new message is after Prev_Msg
1032         --  and before Next_Msg. However, this is where we do a special check
1033         --  for redundant parsing messages, defined as messages posted on the
1034         --  same line. The idea here is that probably such messages are junk
1035         --  from the parser recovering. In full errors mode, we don't do this
1036         --  deletion, but otherwise such messages are discarded at this stage.
1037
1038         if Prev_Msg /= No_Error_Msg
1039           and then Errors.Table (Prev_Msg).Line =
1040                                             Errors.Table (Cur_Msg).Line
1041           and then Errors.Table (Prev_Msg).Sfile =
1042                                             Errors.Table (Cur_Msg).Sfile
1043           and then Compiler_State = Parsing
1044           and then not All_Errors_Mode
1045         then
1046            --  Don't delete unconditional messages and at this stage, don't
1047            --  delete continuation lines (we attempted to delete those earlier
1048            --  if the parent message was deleted.
1049
1050            if not Errors.Table (Cur_Msg).Uncond
1051              and then not Continuation
1052            then
1053               --  Don't delete if prev msg is warning and new msg is an error.
1054               --  This is because we don't want a real error masked by a
1055               --  warning. In all other cases (that is parse errors for the
1056               --  same line that are not unconditional) we do delete the
1057               --  message. This helps to avoid junk extra messages from
1058               --  cascaded parsing errors
1059
1060               if not (Errors.Table (Prev_Msg).Warn
1061                         or else
1062                       Errors.Table (Prev_Msg).Style)
1063                 or else
1064                      (Errors.Table (Cur_Msg).Warn
1065                         or else
1066                       Errors.Table (Cur_Msg).Style)
1067               then
1068                  --  All tests passed, delete the message by simply returning
1069                  --  without any further processing.
1070
1071                  if not Continuation then
1072                     Last_Killed := True;
1073                  end if;
1074
1075                  return;
1076               end if;
1077            end if;
1078         end if;
1079
1080         --  Come here if message is to be inserted in the error chain
1081
1082         if not Continuation then
1083            Last_Killed := False;
1084         end if;
1085
1086         if Prev_Msg = No_Error_Msg then
1087            First_Error_Msg := Cur_Msg;
1088         else
1089            Errors.Table (Prev_Msg).Next := Cur_Msg;
1090         end if;
1091
1092         Errors.Table (Cur_Msg).Next := Next_Msg;
1093
1094         if Next_Msg = No_Error_Msg then
1095            Last_Error_Msg := Cur_Msg;
1096         end if;
1097      end if;
1098
1099      --  Bump appropriate statistics count
1100
1101      if Errors.Table (Cur_Msg).Warn or else Errors.Table (Cur_Msg).Style then
1102         Warnings_Detected := Warnings_Detected + 1;
1103
1104      else
1105         Total_Errors_Detected := Total_Errors_Detected + 1;
1106
1107         if Errors.Table (Cur_Msg).Serious then
1108            Serious_Errors_Detected := Serious_Errors_Detected + 1;
1109            Handle_Serious_Error;
1110         end if;
1111      end if;
1112
1113      --  If too many warnings turn off warnings
1114
1115      if Maximum_Messages /= 0 then
1116         if Warnings_Detected = Maximum_Messages then
1117            Warning_Mode := Suppress;
1118         end if;
1119
1120         --  If too many errors abandon compilation
1121
1122         if Total_Errors_Detected = Maximum_Messages then
1123            raise Unrecoverable_Error;
1124         end if;
1125      end if;
1126   end Error_Msg_Internal;
1127
1128   -----------------
1129   -- Error_Msg_N --
1130   -----------------
1131
1132   procedure Error_Msg_N (Msg : String; N : Node_Or_Entity_Id) is
1133   begin
1134      Error_Msg_NEL (Msg, N, N, Sloc (N));
1135   end Error_Msg_N;
1136
1137   ------------------
1138   -- Error_Msg_NE --
1139   ------------------
1140
1141   procedure Error_Msg_NE
1142     (Msg : String;
1143      N   : Node_Or_Entity_Id;
1144      E   : Node_Or_Entity_Id)
1145   is
1146   begin
1147      Error_Msg_NEL (Msg, N, E, Sloc (N));
1148   end Error_Msg_NE;
1149
1150   -------------------
1151   -- Error_Msg_NEL --
1152   -------------------
1153
1154   procedure Error_Msg_NEL
1155     (Msg           : String;
1156      N             : Node_Or_Entity_Id;
1157      E             : Node_Or_Entity_Id;
1158      Flag_Location : Source_Ptr)
1159   is
1160   begin
1161      if Special_Msg_Delete (Msg, N, E) then
1162         return;
1163      end if;
1164
1165      Test_Style_Warning_Serious_Unconditional_Msg (Msg);
1166
1167      --  Special handling for warning messages
1168
1169      if Is_Warning_Msg then
1170
1171         --  Suppress if no warnings set for either entity or node
1172
1173         if No_Warnings (N) or else No_Warnings (E) then
1174
1175            --  Disable any continuation messages as well
1176
1177            Last_Killed := True;
1178            return;
1179         end if;
1180
1181         --  Suppress if inside loop that is known to be null or is probably
1182         --  null (case where loop executes only if invalid values present).
1183         --  In either case warnings in the loop are likely to be junk.
1184
1185         declare
1186            P : Node_Id;
1187
1188         begin
1189            P := Parent (N);
1190            while Present (P) loop
1191               if Nkind (P) = N_Loop_Statement
1192                 and then Suppress_Loop_Warnings (P)
1193               then
1194                  return;
1195               end if;
1196
1197               P := Parent (P);
1198            end loop;
1199         end;
1200      end if;
1201
1202      --  Test for message to be output
1203
1204      if All_Errors_Mode
1205        or else Is_Unconditional_Msg
1206        or else Is_Warning_Msg
1207        or else OK_Node (N)
1208        or else (Msg (Msg'First) = '\' and then not Last_Killed)
1209      then
1210         Debug_Output (N);
1211         Error_Msg_Node_1 := E;
1212         Error_Msg (Msg, Flag_Location);
1213
1214      else
1215         Last_Killed := True;
1216      end if;
1217
1218      if not (Is_Warning_Msg or Is_Style_Msg) then
1219         Set_Posted (N);
1220      end if;
1221   end Error_Msg_NEL;
1222
1223   ------------------
1224   -- Error_Msg_NW --
1225   ------------------
1226
1227   procedure Error_Msg_NW
1228     (Eflag : Boolean;
1229      Msg   : String;
1230      N     : Node_Or_Entity_Id)
1231   is
1232   begin
1233      if Eflag
1234        and then In_Extended_Main_Source_Unit (N)
1235        and then Comes_From_Source (N)
1236      then
1237         Error_Msg_NEL (Msg, N, N, Sloc (N));
1238      end if;
1239   end Error_Msg_NW;
1240
1241   -----------------
1242   -- Error_Msg_S --
1243   -----------------
1244
1245   procedure Error_Msg_S (Msg : String) is
1246   begin
1247      Error_Msg (Msg, Scan_Ptr);
1248   end Error_Msg_S;
1249
1250   ------------------
1251   -- Error_Msg_SC --
1252   ------------------
1253
1254   procedure Error_Msg_SC (Msg : String) is
1255   begin
1256      --  If we are at end of file, post the flag after the previous token
1257
1258      if Token = Tok_EOF then
1259         Error_Msg_AP (Msg);
1260
1261      --  For all other cases the message is posted at the current token
1262      --  pointer position
1263
1264      else
1265         Error_Msg (Msg, Token_Ptr);
1266      end if;
1267   end Error_Msg_SC;
1268
1269   ------------------
1270   -- Error_Msg_SP --
1271   ------------------
1272
1273   procedure Error_Msg_SP (Msg : String) is
1274   begin
1275      --  Note: in the case where there is no previous token, Prev_Token_Ptr
1276      --  is set to Source_First, which is a reasonable position for the
1277      --  error flag in this situation
1278
1279      Error_Msg (Msg, Prev_Token_Ptr);
1280   end Error_Msg_SP;
1281
1282   --------------
1283   -- Finalize --
1284   --------------
1285
1286   procedure Finalize (Last_Call : Boolean) is
1287      Cur : Error_Msg_Id;
1288      Nxt : Error_Msg_Id;
1289      F   : Error_Msg_Id;
1290
1291      procedure Delete_Warning (E : Error_Msg_Id);
1292      --  Delete a message if not already deleted and adjust warning count
1293
1294      --------------------
1295      -- Delete_Warning --
1296      --------------------
1297
1298      procedure Delete_Warning (E : Error_Msg_Id) is
1299      begin
1300         if not Errors.Table (E).Deleted then
1301            Errors.Table (E).Deleted := True;
1302            Warnings_Detected := Warnings_Detected - 1;
1303         end if;
1304      end Delete_Warning;
1305
1306   --  Start of message for Finalize
1307
1308   begin
1309      --  Set Prev pointers
1310
1311      Cur := First_Error_Msg;
1312      while Cur /= No_Error_Msg loop
1313         Nxt := Errors.Table (Cur).Next;
1314         exit when Nxt = No_Error_Msg;
1315         Errors.Table (Nxt).Prev := Cur;
1316         Cur := Nxt;
1317      end loop;
1318
1319      --  Eliminate any duplicated error messages from the list. This is
1320      --  done after the fact to avoid problems with Change_Error_Text.
1321
1322      Cur := First_Error_Msg;
1323      while Cur /= No_Error_Msg loop
1324         Nxt := Errors.Table (Cur).Next;
1325
1326         F := Nxt;
1327         while F /= No_Error_Msg
1328           and then Errors.Table (F).Sptr = Errors.Table (Cur).Sptr
1329         loop
1330            Check_Duplicate_Message (Cur, F);
1331            F := Errors.Table (F).Next;
1332         end loop;
1333
1334         Cur := Nxt;
1335      end loop;
1336
1337      --  Mark any messages suppressed by specific warnings as Deleted
1338
1339      Cur := First_Error_Msg;
1340      while Cur /= No_Error_Msg loop
1341         declare
1342            CE : Error_Msg_Object renames Errors.Table (Cur);
1343
1344         begin
1345            if (CE.Warn and not CE.Deleted)
1346              and then (Warning_Specifically_Suppressed (CE.Sptr, CE.Text) /=
1347                                                                   No_String
1348                          or else
1349                        Warning_Specifically_Suppressed (CE.Optr, CE.Text) /=
1350                                                                   No_String)
1351            then
1352               Delete_Warning (Cur);
1353
1354               --  If this is a continuation, delete previous messages
1355
1356               F := Cur;
1357               while Errors.Table (F).Msg_Cont loop
1358                  F := Errors.Table (F).Prev;
1359                  Delete_Warning (F);
1360               end loop;
1361
1362               --  Delete any following continuations
1363
1364               F := Cur;
1365               loop
1366                  F := Errors.Table (F).Next;
1367                  exit when F = No_Error_Msg;
1368                  exit when not Errors.Table (F).Msg_Cont;
1369                  Delete_Warning (F);
1370               end loop;
1371            end if;
1372         end;
1373
1374         Cur := Errors.Table (Cur).Next;
1375      end loop;
1376
1377      Finalize_Called := True;
1378
1379      --  Check consistency of specific warnings (may add warnings). We only
1380      --  do this on the last call, after all possible warnings are posted.
1381
1382      if Last_Call then
1383         Validate_Specific_Warnings (Error_Msg'Access);
1384      end if;
1385   end Finalize;
1386
1387   ----------------
1388   -- First_Node --
1389   ----------------
1390
1391   function First_Node (C : Node_Id) return Node_Id is
1392      Orig     : constant Node_Id           := Original_Node (C);
1393      Loc      : constant Source_Ptr        := Sloc (Orig);
1394      Sfile    : constant Source_File_Index := Get_Source_File_Index (Loc);
1395      Earliest : Node_Id;
1396      Eloc     : Source_Ptr;
1397
1398      function Test_Earlier (N : Node_Id) return Traverse_Result;
1399      --  Function applied to every node in the construct
1400
1401      procedure Search_Tree_First is new Traverse_Proc (Test_Earlier);
1402      --  Create traversal procedure
1403
1404      ------------------
1405      -- Test_Earlier --
1406      ------------------
1407
1408      function Test_Earlier (N : Node_Id) return Traverse_Result is
1409         Norig : constant Node_Id    := Original_Node (N);
1410         Loc   : constant Source_Ptr := Sloc (Norig);
1411
1412      begin
1413         --  Check for earlier
1414
1415         if Loc < Eloc
1416
1417           --  Ignore nodes with no useful location information
1418
1419           and then Loc /= Standard_Location
1420           and then Loc /= No_Location
1421
1422           --  Ignore nodes from a different file. This ensures against cases
1423           --  of strange foreign code somehow being present. We don't want
1424           --  wild placement of messages if that happens.
1425
1426           and then Get_Source_File_Index (Loc) = Sfile
1427         then
1428            Earliest := Norig;
1429            Eloc     := Loc;
1430         end if;
1431
1432         return OK_Orig;
1433      end Test_Earlier;
1434
1435   --  Start of processing for First_Node
1436
1437   begin
1438      if Nkind (Orig) in N_Subexpr then
1439         Earliest := Orig;
1440         Eloc := Loc;
1441         Search_Tree_First (Orig);
1442         return Earliest;
1443
1444      else
1445         return Orig;
1446      end if;
1447   end First_Node;
1448
1449   ----------------
1450   -- First_Sloc --
1451   ----------------
1452
1453   function First_Sloc (N : Node_Id) return Source_Ptr is
1454      SI : constant Source_File_Index := Source_Index (Get_Source_Unit (N));
1455      SF : constant Source_Ptr        := Source_First (SI);
1456      F  : Node_Id;
1457      S  : Source_Ptr;
1458
1459   begin
1460      F := First_Node (N);
1461      S := Sloc (F);
1462
1463      --  The following circuit is a bit subtle. When we have parenthesized
1464      --  expressions, then the Sloc will not record the location of the paren,
1465      --  but we would like to post the flag on the paren. So what we do is to
1466      --  crawl up the tree from the First_Node, adjusting the Sloc value for
1467      --  any parentheses we know are present. Yes, we know this circuit is not
1468      --  100% reliable (e.g. because we don't record all possible paren level
1469      --  values), but this is only for an error message so it is good enough.
1470
1471      Node_Loop : loop
1472         Paren_Loop : for J in 1 .. Paren_Count (F) loop
1473
1474            --  We don't look more than 12 characters behind the current
1475            --  location, and in any case not past the front of the source.
1476
1477            Search_Loop : for K in 1 .. 12 loop
1478               exit Search_Loop when S = SF;
1479
1480               if Source_Text (SI) (S - 1) = '(' then
1481                  S := S - 1;
1482                  exit Search_Loop;
1483
1484               elsif Source_Text (SI) (S - 1) <= ' ' then
1485                  S := S - 1;
1486
1487               else
1488                  exit Search_Loop;
1489               end if;
1490            end loop Search_Loop;
1491         end loop Paren_Loop;
1492
1493         exit Node_Loop when F = N;
1494         F := Parent (F);
1495         exit Node_Loop when Nkind (F) not in N_Subexpr;
1496      end loop Node_Loop;
1497
1498      return S;
1499   end First_Sloc;
1500
1501   -----------------------
1502   -- Get_Ignore_Errors --
1503   -----------------------
1504
1505   function Get_Ignore_Errors return Boolean is
1506   begin
1507      return Errors_Must_Be_Ignored;
1508   end Get_Ignore_Errors;
1509
1510   ----------------
1511   -- Initialize --
1512   ----------------
1513
1514   procedure Initialize is
1515   begin
1516      Errors.Init;
1517      First_Error_Msg := No_Error_Msg;
1518      Last_Error_Msg := No_Error_Msg;
1519      Serious_Errors_Detected := 0;
1520      Total_Errors_Detected := 0;
1521      Warnings_Treated_As_Errors := 0;
1522      Warnings_Detected := 0;
1523      Warnings_As_Errors_Count := 0;
1524      Cur_Msg := No_Error_Msg;
1525      List_Pragmas.Init;
1526
1527      --  Initialize warnings tables
1528
1529      Warnings.Init;
1530      Specific_Warnings.Init;
1531   end Initialize;
1532
1533   -----------------
1534   -- No_Warnings --
1535   -----------------
1536
1537   function No_Warnings (N : Node_Or_Entity_Id) return Boolean is
1538   begin
1539      if Error_Posted (N) then
1540         return True;
1541
1542      elsif Nkind (N) in N_Entity and then Has_Warnings_Off (N) then
1543         return True;
1544
1545      elsif Is_Entity_Name (N)
1546        and then Present (Entity (N))
1547        and then Has_Warnings_Off (Entity (N))
1548      then
1549         return True;
1550
1551      else
1552         return False;
1553      end if;
1554   end No_Warnings;
1555
1556   -------------
1557   -- OK_Node --
1558   -------------
1559
1560   function OK_Node (N : Node_Id) return Boolean is
1561      K : constant Node_Kind := Nkind (N);
1562
1563   begin
1564      if Error_Posted (N) then
1565         return False;
1566
1567      elsif K in N_Has_Etype
1568        and then Present (Etype (N))
1569        and then Error_Posted (Etype (N))
1570      then
1571         return False;
1572
1573      elsif (K in N_Op
1574              or else K = N_Attribute_Reference
1575              or else K = N_Character_Literal
1576              or else K = N_Expanded_Name
1577              or else K = N_Identifier
1578              or else K = N_Operator_Symbol)
1579        and then Present (Entity (N))
1580        and then Error_Posted (Entity (N))
1581      then
1582         return False;
1583      else
1584         return True;
1585      end if;
1586   end OK_Node;
1587
1588   ---------------------
1589   -- Output_Messages --
1590   ---------------------
1591
1592   procedure Output_Messages is
1593      E        : Error_Msg_Id;
1594      Err_Flag : Boolean;
1595
1596      procedure Write_Error_Summary;
1597      --  Write error summary
1598
1599      procedure Write_Header (Sfile : Source_File_Index);
1600      --  Write header line (compiling or checking given file)
1601
1602      procedure Write_Max_Errors;
1603      --  Write message if max errors reached
1604
1605      -------------------------
1606      -- Write_Error_Summary --
1607      -------------------------
1608
1609      procedure Write_Error_Summary is
1610      begin
1611         --  Extra blank line if error messages or source listing were output
1612
1613         if Total_Errors_Detected + Warnings_Detected > 0
1614           or else Full_List
1615         then
1616            Write_Eol;
1617         end if;
1618
1619         --  Message giving number of lines read and number of errors detected.
1620         --  This normally goes to Standard_Output. The exception is when brief
1621         --  mode is not set, verbose mode (or full list mode) is set, and
1622         --  there are errors. In this case we send the message to standard
1623         --  error to make sure that *something* appears on standard error in
1624         --  an error situation.
1625
1626         --  Formerly, only the "# errors" suffix was sent to stderr, whereas
1627         --  "# lines:" appeared on stdout. This caused problems on VMS when
1628         --  the stdout buffer was flushed, giving an extra line feed after
1629         --  the prefix.
1630
1631         if Total_Errors_Detected + Warnings_Detected /= 0
1632           and then not Brief_Output
1633           and then (Verbose_Mode or Full_List)
1634         then
1635            Set_Standard_Error;
1636         end if;
1637
1638         --  Message giving total number of lines. Don't give this message if
1639         --  the Main_Source line is unknown (this happens in error situations,
1640         --  e.g. when integrated preprocessing fails).
1641
1642         if Main_Source_File /= No_Source_File then
1643            Write_Str (" ");
1644            Write_Int (Num_Source_Lines (Main_Source_File));
1645
1646            if Num_Source_Lines (Main_Source_File) = 1 then
1647               Write_Str (" line: ");
1648            else
1649               Write_Str (" lines: ");
1650            end if;
1651         end if;
1652
1653         if Total_Errors_Detected = 0 then
1654            Write_Str ("No errors");
1655
1656         elsif Total_Errors_Detected = 1 then
1657            Write_Str ("1 error");
1658
1659         else
1660            Write_Int (Total_Errors_Detected);
1661            Write_Str (" errors");
1662         end if;
1663
1664         if Warnings_Detected /= 0 then
1665            Write_Str (", ");
1666            Write_Int (Warnings_Detected);
1667            Write_Str (" warning");
1668
1669            if Warnings_Detected /= 1 then
1670               Write_Char ('s');
1671            end if;
1672
1673            if Warning_Mode = Treat_As_Error then
1674               Write_Str (" (treated as error");
1675
1676               if Warnings_Detected /= 1 then
1677                  Write_Char ('s');
1678               end if;
1679
1680               Write_Char (')');
1681
1682            elsif Warnings_Treated_As_Errors /= 0 then
1683               Write_Str (" (");
1684               Write_Int (Warnings_Treated_As_Errors);
1685               Write_Str (" treated as errors)");
1686            end if;
1687         end if;
1688
1689         Write_Eol;
1690         Set_Standard_Output;
1691      end Write_Error_Summary;
1692
1693      ------------------
1694      -- Write_Header --
1695      ------------------
1696
1697      procedure Write_Header (Sfile : Source_File_Index) is
1698      begin
1699         if Verbose_Mode or Full_List then
1700            if Original_Operating_Mode = Generate_Code then
1701               Write_Str ("Compiling: ");
1702            else
1703               Write_Str ("Checking: ");
1704            end if;
1705
1706            Write_Name (Full_File_Name (Sfile));
1707
1708            if not Debug_Flag_7 then
1709               Write_Str (" (source file time stamp: ");
1710               Write_Time_Stamp (Sfile);
1711               Write_Char (')');
1712            end if;
1713
1714            Write_Eol;
1715         end if;
1716      end Write_Header;
1717
1718      ----------------------
1719      -- Write_Max_Errors --
1720      ----------------------
1721
1722      procedure Write_Max_Errors is
1723      begin
1724         if Maximum_Messages /= 0 then
1725            if Warnings_Detected >= Maximum_Messages then
1726               Set_Standard_Error;
1727               Write_Line ("maximum number of warnings output");
1728               Write_Line ("any further warnings suppressed");
1729               Set_Standard_Output;
1730            end if;
1731
1732            --  If too many errors print message
1733
1734            if Total_Errors_Detected >= Maximum_Messages then
1735               Set_Standard_Error;
1736               Write_Line ("fatal error: maximum number of errors detected");
1737               Set_Standard_Output;
1738            end if;
1739         end if;
1740      end Write_Max_Errors;
1741
1742   --  Start of processing for Output_Messages
1743
1744   begin
1745      --  Error if Finalize has not been called
1746
1747      if not Finalize_Called then
1748         raise Program_Error;
1749      end if;
1750
1751      --  Reset current error source file if the main unit has a pragma
1752      --  Source_Reference. This ensures outputting the proper name of
1753      --  the source file in this situation.
1754
1755      if Main_Source_File = No_Source_File
1756        or else Num_SRef_Pragmas (Main_Source_File) /= 0
1757      then
1758         Current_Error_Source_File := No_Source_File;
1759      end if;
1760
1761      --  Brief Error mode
1762
1763      if Brief_Output or (not Full_List and not Verbose_Mode) then
1764         Set_Standard_Error;
1765
1766         E := First_Error_Msg;
1767         while E /= No_Error_Msg loop
1768            if not Errors.Table (E).Deleted and then not Debug_Flag_KK then
1769               if Full_Path_Name_For_Brief_Errors then
1770                  Write_Name (Full_Ref_Name (Errors.Table (E).Sfile));
1771               else
1772                  Write_Name (Reference_Name (Errors.Table (E).Sfile));
1773               end if;
1774
1775               Write_Char (':');
1776               Write_Int (Int (Physical_To_Logical
1777                                (Errors.Table (E).Line,
1778                                 Errors.Table (E).Sfile)));
1779               Write_Char (':');
1780
1781               if Errors.Table (E).Col < 10 then
1782                  Write_Char ('0');
1783               end if;
1784
1785               Write_Int (Int (Errors.Table (E).Col));
1786               Write_Str (": ");
1787               Output_Msg_Text (E);
1788               Write_Eol;
1789            end if;
1790
1791            E := Errors.Table (E).Next;
1792         end loop;
1793
1794         Set_Standard_Output;
1795      end if;
1796
1797      --  Full source listing case
1798
1799      if Full_List then
1800         List_Pragmas_Index := 1;
1801         List_Pragmas_Mode := True;
1802         E := First_Error_Msg;
1803
1804         --  Normal case, to stdout (copyright notice already output)
1805
1806         if Full_List_File_Name = null then
1807            if not Debug_Flag_7 then
1808               Write_Eol;
1809            end if;
1810
1811         --  Output to file
1812
1813         else
1814            Create_List_File_Access.all (Full_List_File_Name.all);
1815            Set_Special_Output (Write_List_Info_Access.all'Access);
1816
1817            --  Write copyright notice to file
1818
1819            if not Debug_Flag_7 then
1820               Write_Str ("GNAT ");
1821               Write_Str (Gnat_Version_String);
1822               Write_Eol;
1823               Write_Str ("Copyright 1992-" &
1824                          Current_Year &
1825                          ", Free Software Foundation, Inc.");
1826               Write_Eol;
1827            end if;
1828         end if;
1829
1830         --  First list extended main source file units with errors
1831
1832         for U in Main_Unit .. Last_Unit loop
1833            if In_Extended_Main_Source_Unit (Cunit_Entity (U))
1834
1835              --  If debug flag d.m is set, only the main source is listed
1836
1837              and then (U = Main_Unit or else not Debug_Flag_Dot_M)
1838
1839              --  If the unit of the entity does not come from source, it is
1840              --  an implicit subprogram declaration for a child subprogram.
1841              --  Do not emit errors for it, they are listed with the body.
1842
1843              and then
1844                (No (Cunit_Entity (U))
1845                   or else Comes_From_Source (Cunit_Entity (U))
1846                   or else not Is_Subprogram (Cunit_Entity (U)))
1847            then
1848               declare
1849                  Sfile : constant Source_File_Index := Source_Index (U);
1850
1851               begin
1852                  Write_Eol;
1853
1854                  --  Only write the header if Sfile is known
1855
1856                  if Sfile /= No_Source_File then
1857                     Write_Header (Sfile);
1858                     Write_Eol;
1859                  end if;
1860
1861                  --  Normally, we don't want an "error messages from file"
1862                  --  message when listing the entire file, so we set the
1863                  --  current source file as the current error source file.
1864                  --  However, the old style of doing things was to list this
1865                  --  message if pragma Source_Reference is present, even for
1866                  --  the main unit. Since the purpose of the -gnatd.m switch
1867                  --  is to duplicate the old behavior, we skip the reset if
1868                  --  this debug flag is set.
1869
1870                  if not Debug_Flag_Dot_M then
1871                     Current_Error_Source_File := Sfile;
1872                  end if;
1873
1874                  --  Only output the listing if Sfile is known, to avoid
1875                  --  crashing the compiler.
1876
1877                  if Sfile /= No_Source_File then
1878                     for N in 1 .. Last_Source_Line (Sfile) loop
1879                        while E /= No_Error_Msg
1880                          and then Errors.Table (E).Deleted
1881                        loop
1882                           E := Errors.Table (E).Next;
1883                        end loop;
1884
1885                        Err_Flag :=
1886                          E /= No_Error_Msg
1887                          and then Errors.Table (E).Line = N
1888                          and then Errors.Table (E).Sfile = Sfile;
1889
1890                        Output_Source_Line (N, Sfile, Err_Flag);
1891
1892                        if Err_Flag then
1893                           Output_Error_Msgs (E);
1894
1895                           if not Debug_Flag_2 then
1896                              Write_Eol;
1897                           end if;
1898                        end if;
1899                     end loop;
1900                  end if;
1901               end;
1902            end if;
1903         end loop;
1904
1905         --  Then output errors, if any, for subsidiary units not in the
1906         --  main extended unit.
1907
1908         --  Note: if debug flag d.m set, include errors for any units other
1909         --  than the main unit in the extended source unit (e.g. spec and
1910         --  subunits for a body).
1911
1912         while E /= No_Error_Msg
1913           and then (not In_Extended_Main_Source_Unit (Errors.Table (E).Sptr)
1914                       or else
1915                        (Debug_Flag_Dot_M
1916                          and then Get_Source_Unit
1917                                     (Errors.Table (E).Sptr) /= Main_Unit))
1918         loop
1919            if Errors.Table (E).Deleted then
1920               E := Errors.Table (E).Next;
1921
1922            else
1923               Write_Eol;
1924               Output_Source_Line
1925                 (Errors.Table (E).Line, Errors.Table (E).Sfile, True);
1926               Output_Error_Msgs (E);
1927            end if;
1928         end loop;
1929
1930         --  If output to file, write extra copy of error summary to the
1931         --  output file, and then close it.
1932
1933         if Full_List_File_Name /= null then
1934            Write_Error_Summary;
1935            Write_Max_Errors;
1936            Close_List_File_Access.all;
1937            Cancel_Special_Output;
1938         end if;
1939      end if;
1940
1941      --  Verbose mode (error lines only with error flags). Normally this is
1942      --  ignored in full list mode, unless we are listing to a file, in which
1943      --  case we still generate -gnatv output to standard output.
1944
1945      if Verbose_Mode
1946        and then (not Full_List or else Full_List_File_Name /= null)
1947      then
1948         Write_Eol;
1949
1950         --  Output the header only when Main_Source_File is known
1951
1952         if Main_Source_File /= No_Source_File then
1953            Write_Header (Main_Source_File);
1954         end if;
1955
1956         E := First_Error_Msg;
1957
1958         --  Loop through error lines
1959
1960         while E /= No_Error_Msg loop
1961            if Errors.Table (E).Deleted then
1962               E := Errors.Table (E).Next;
1963            else
1964               Write_Eol;
1965               Output_Source_Line
1966                 (Errors.Table (E).Line, Errors.Table (E).Sfile, True);
1967               Output_Error_Msgs (E);
1968            end if;
1969         end loop;
1970      end if;
1971
1972      --  Output error summary if verbose or full list mode
1973
1974      if Verbose_Mode or else Full_List then
1975         Write_Error_Summary;
1976      end if;
1977
1978      Write_Max_Errors;
1979
1980      if Warning_Mode = Treat_As_Error then
1981         Total_Errors_Detected := Total_Errors_Detected + Warnings_Detected;
1982         Warnings_Detected := 0;
1983      end if;
1984   end Output_Messages;
1985
1986   ------------------------
1987   -- Output_Source_Line --
1988   ------------------------
1989
1990   procedure Output_Source_Line
1991     (L     : Physical_Line_Number;
1992      Sfile : Source_File_Index;
1993      Errs  : Boolean)
1994   is
1995      S : Source_Ptr;
1996      C : Character;
1997
1998      Line_Number_Output : Boolean := False;
1999      --  Set True once line number is output
2000
2001      Empty_Line : Boolean := True;
2002      --  Set False if line includes at least one character
2003
2004   begin
2005      if Sfile /= Current_Error_Source_File then
2006         Write_Str ("==============Error messages for ");
2007
2008         case Sinput.File_Type (Sfile) is
2009            when Sinput.Src =>
2010               Write_Str ("source");
2011
2012            when Sinput.Config =>
2013               Write_Str ("configuration pragmas");
2014
2015            when Sinput.Def =>
2016               Write_Str ("symbol definition");
2017
2018            when Sinput.Preproc =>
2019               Write_Str ("preprocessing data");
2020         end case;
2021
2022         Write_Str (" file: ");
2023         Write_Name (Full_File_Name (Sfile));
2024         Write_Eol;
2025
2026         if Num_SRef_Pragmas (Sfile) > 0 then
2027            Write_Str ("--------------Line numbers from file: ");
2028            Write_Name (Full_Ref_Name (Sfile));
2029            Write_Str (" (starting at line ");
2030            Write_Int (Int (First_Mapped_Line (Sfile)));
2031            Write_Char (')');
2032            Write_Eol;
2033         end if;
2034
2035         Current_Error_Source_File := Sfile;
2036      end if;
2037
2038      if Errs or List_Pragmas_Mode then
2039         Output_Line_Number (Physical_To_Logical (L, Sfile));
2040         Line_Number_Output := True;
2041      end if;
2042
2043      S := Line_Start (L, Sfile);
2044
2045      loop
2046         C := Source_Text (Sfile) (S);
2047         exit when C = ASCII.LF or else C = ASCII.CR or else C = EOF;
2048
2049         --  Deal with matching entry in List_Pragmas table
2050
2051         if Full_List
2052           and then List_Pragmas_Index <= List_Pragmas.Last
2053           and then S = List_Pragmas.Table (List_Pragmas_Index).Ploc
2054         then
2055            case List_Pragmas.Table (List_Pragmas_Index).Ptyp is
2056               when Page =>
2057                  Write_Char (C);
2058
2059                  --  Ignore if on line with errors so that error flags
2060                  --  get properly listed with the error line .
2061
2062                  if not Errs then
2063                     Write_Char (ASCII.FF);
2064                  end if;
2065
2066               when List_On =>
2067                  List_Pragmas_Mode := True;
2068
2069                  if not Line_Number_Output then
2070                     Output_Line_Number (Physical_To_Logical (L, Sfile));
2071                     Line_Number_Output := True;
2072                  end if;
2073
2074                  Write_Char (C);
2075
2076               when List_Off =>
2077                  Write_Char (C);
2078                  List_Pragmas_Mode := False;
2079            end case;
2080
2081            List_Pragmas_Index := List_Pragmas_Index + 1;
2082
2083         --  Normal case (no matching entry in List_Pragmas table)
2084
2085         else
2086            if Errs or List_Pragmas_Mode then
2087               Write_Char (C);
2088            end if;
2089         end if;
2090
2091         Empty_Line := False;
2092         S := S + 1;
2093      end loop;
2094
2095      --  If we have output a source line, then add the line terminator, with
2096      --  training spaces preserved (so we output the line exactly as input).
2097
2098      if Line_Number_Output then
2099         if Empty_Line then
2100            Write_Eol;
2101         else
2102            Write_Eol_Keep_Blanks;
2103         end if;
2104      end if;
2105   end Output_Source_Line;
2106
2107   -----------------------------
2108   -- Remove_Warning_Messages --
2109   -----------------------------
2110
2111   procedure Remove_Warning_Messages (N : Node_Id) is
2112
2113      function Check_For_Warning (N : Node_Id) return Traverse_Result;
2114      --  This function checks one node for a possible warning message
2115
2116      function Check_All_Warnings is new Traverse_Func (Check_For_Warning);
2117      --  This defines the traversal operation
2118
2119      -----------------------
2120      -- Check_For_Warning --
2121      -----------------------
2122
2123      function Check_For_Warning (N : Node_Id) return Traverse_Result is
2124         Loc : constant Source_Ptr := Sloc (N);
2125         E   : Error_Msg_Id;
2126
2127         function To_Be_Removed (E : Error_Msg_Id) return Boolean;
2128         --  Returns True for a message that is to be removed. Also adjusts
2129         --  warning count appropriately.
2130
2131         -------------------
2132         -- To_Be_Removed --
2133         -------------------
2134
2135         function To_Be_Removed (E : Error_Msg_Id) return Boolean is
2136         begin
2137            if E /= No_Error_Msg
2138
2139               --  Don't remove if location does not match
2140
2141               and then Errors.Table (E).Optr = Loc
2142
2143               --  Don't remove if not warning/info message. Note that we do
2144               --  not remove style messages here. They are warning messages
2145               --  but not ones we want removed in this context.
2146
2147               and then Errors.Table (E).Warn
2148
2149               --  Don't remove unconditional messages
2150
2151               and then not Errors.Table (E).Uncond
2152            then
2153               Warnings_Detected := Warnings_Detected - 1;
2154               return True;
2155
2156            --  No removal required
2157
2158            else
2159               return False;
2160            end if;
2161         end To_Be_Removed;
2162
2163      --  Start of processing for Check_For_Warnings
2164
2165      begin
2166         while To_Be_Removed (First_Error_Msg) loop
2167            First_Error_Msg := Errors.Table (First_Error_Msg).Next;
2168         end loop;
2169
2170         if First_Error_Msg = No_Error_Msg then
2171            Last_Error_Msg := No_Error_Msg;
2172         end if;
2173
2174         E := First_Error_Msg;
2175         while E /= No_Error_Msg loop
2176            while To_Be_Removed (Errors.Table (E).Next) loop
2177               Errors.Table (E).Next :=
2178                 Errors.Table (Errors.Table (E).Next).Next;
2179
2180               if Errors.Table (E).Next = No_Error_Msg then
2181                  Last_Error_Msg := E;
2182               end if;
2183            end loop;
2184
2185            E := Errors.Table (E).Next;
2186         end loop;
2187
2188         if Nkind (N) = N_Raise_Constraint_Error
2189           and then Original_Node (N) /= N
2190           and then No (Condition (N))
2191         then
2192            --  Warnings may have been posted on subexpressions of the original
2193            --  tree. We place the original node back on the tree to remove
2194            --  those warnings, whose sloc do not match those of any node in
2195            --  the current tree. Given that we are in unreachable code, this
2196            --  modification to the tree is harmless.
2197
2198            declare
2199               Status : Traverse_Final_Result;
2200
2201            begin
2202               if Is_List_Member (N) then
2203                  Set_Condition (N, Original_Node (N));
2204                  Status := Check_All_Warnings (Condition (N));
2205               else
2206                  Rewrite (N, Original_Node (N));
2207                  Status := Check_All_Warnings (N);
2208               end if;
2209
2210               return Status;
2211            end;
2212
2213         else
2214            return OK;
2215         end if;
2216      end Check_For_Warning;
2217
2218   --  Start of processing for Remove_Warning_Messages
2219
2220   begin
2221      if Warnings_Detected /= 0 then
2222         declare
2223            Discard : Traverse_Final_Result;
2224            pragma Warnings (Off, Discard);
2225
2226         begin
2227            Discard := Check_All_Warnings (N);
2228         end;
2229      end if;
2230   end Remove_Warning_Messages;
2231
2232   procedure Remove_Warning_Messages (L : List_Id) is
2233      Stat : Node_Id;
2234   begin
2235      if Is_Non_Empty_List (L) then
2236         Stat := First (L);
2237         while Present (Stat) loop
2238            Remove_Warning_Messages (Stat);
2239            Next (Stat);
2240         end loop;
2241      end if;
2242   end Remove_Warning_Messages;
2243
2244   ---------------------------
2245   -- Set_Identifier_Casing --
2246   ---------------------------
2247
2248   procedure Set_Identifier_Casing
2249     (Identifier_Name : System.Address;
2250      File_Name       : System.Address)
2251   is
2252      Ident : constant Big_String_Ptr := To_Big_String_Ptr (Identifier_Name);
2253      File  : constant Big_String_Ptr := To_Big_String_Ptr (File_Name);
2254      Flen  : Natural;
2255
2256      Desired_Case : Casing_Type := Mixed_Case;
2257      --  Casing required for result. Default value of Mixed_Case is used if
2258      --  for some reason we cannot find the right file name in the table.
2259
2260   begin
2261      --  Get length of file name
2262
2263      Flen := 0;
2264      while File (Flen + 1) /= ASCII.NUL loop
2265         Flen := Flen + 1;
2266      end loop;
2267
2268      --  Loop through file names to find matching one. This is a bit slow, but
2269      --  we only do it in error situations so it is not so terrible. Note that
2270      --  if the loop does not exit, then the desired case will be left set to
2271      --  Mixed_Case, this can happen if the name was not in canonical form,
2272      --  and gets canonicalized on VMS. Possibly we could fix this by
2273      --  unconditionally canonicalizing these names ???
2274
2275      for J in 1 .. Last_Source_File loop
2276         Get_Name_String (Full_Debug_Name (J));
2277
2278         if Name_Len = Flen
2279           and then Name_Buffer (1 .. Name_Len) = String (File (1 .. Flen))
2280         then
2281            Desired_Case := Identifier_Casing (J);
2282            exit;
2283         end if;
2284      end loop;
2285
2286      --  Copy identifier as given to Name_Buffer
2287
2288      for J in Name_Buffer'Range loop
2289         Name_Buffer (J) := Ident (J);
2290
2291         if Name_Buffer (J) = ASCII.NUL then
2292            Name_Len := J - 1;
2293            exit;
2294         end if;
2295      end loop;
2296
2297      Set_Casing (Desired_Case);
2298   end Set_Identifier_Casing;
2299
2300   -----------------------
2301   -- Set_Ignore_Errors --
2302   -----------------------
2303
2304   procedure Set_Ignore_Errors (To : Boolean) is
2305   begin
2306      Errors_Must_Be_Ignored := To;
2307   end Set_Ignore_Errors;
2308
2309   ------------------------------
2310   -- Set_Msg_Insertion_Column --
2311   ------------------------------
2312
2313   procedure Set_Msg_Insertion_Column is
2314   begin
2315      if RM_Column_Check then
2316         Set_Msg_Str (" in column ");
2317         Set_Msg_Int (Int (Error_Msg_Col) + 1);
2318      end if;
2319   end Set_Msg_Insertion_Column;
2320
2321   ----------------------------
2322   -- Set_Msg_Insertion_Node --
2323   ----------------------------
2324
2325   procedure Set_Msg_Insertion_Node is
2326      K : Node_Kind;
2327
2328   begin
2329      Suppress_Message :=
2330        Error_Msg_Node_1 = Error
2331          or else Error_Msg_Node_1 = Any_Type;
2332
2333      if Error_Msg_Node_1 = Empty then
2334         Set_Msg_Blank_Conditional;
2335         Set_Msg_Str ("<empty>");
2336
2337      elsif Error_Msg_Node_1 = Error then
2338         Set_Msg_Blank;
2339         Set_Msg_Str ("<error>");
2340
2341      elsif Error_Msg_Node_1 = Standard_Void_Type then
2342         Set_Msg_Blank;
2343         Set_Msg_Str ("procedure name");
2344
2345      elsif Nkind (Error_Msg_Node_1) in N_Entity
2346        and then Ekind (Error_Msg_Node_1) = E_Anonymous_Access_Subprogram_Type
2347      then
2348         Set_Msg_Blank;
2349         Set_Msg_Str ("access to subprogram");
2350
2351      else
2352         Set_Msg_Blank_Conditional;
2353
2354         --  Output name
2355
2356         K := Nkind (Error_Msg_Node_1);
2357
2358         --  If we have operator case, skip quotes since name of operator
2359         --  itself will supply the required quotations. An operator can be an
2360         --  applied use in an expression or an explicit operator symbol, or an
2361         --  identifier whose name indicates it is an operator.
2362
2363         if K in N_Op
2364           or else K = N_Operator_Symbol
2365           or else K = N_Defining_Operator_Symbol
2366           or else ((K = N_Identifier or else K = N_Defining_Identifier)
2367                      and then Is_Operator_Name (Chars (Error_Msg_Node_1)))
2368         then
2369            Set_Msg_Node (Error_Msg_Node_1);
2370
2371         --  Normal case, not an operator, surround with quotes
2372
2373         else
2374            Set_Msg_Quote;
2375            Set_Qualification (Error_Msg_Qual_Level, Error_Msg_Node_1);
2376            Set_Msg_Node (Error_Msg_Node_1);
2377            Set_Msg_Quote;
2378         end if;
2379      end if;
2380
2381      --  The following assignment ensures that a second ampersand insertion
2382      --  character will correspond to the Error_Msg_Node_2 parameter. We
2383      --  suppress possible validity checks in case operating in -gnatVa mode,
2384      --  and Error_Msg_Node_2 is not needed and has not been set.
2385
2386      declare
2387         pragma Suppress (Range_Check);
2388      begin
2389         Error_Msg_Node_1 := Error_Msg_Node_2;
2390      end;
2391   end Set_Msg_Insertion_Node;
2392
2393   --------------------------------------
2394   -- Set_Msg_Insertion_Type_Reference --
2395   --------------------------------------
2396
2397   procedure Set_Msg_Insertion_Type_Reference (Flag : Source_Ptr) is
2398      Ent : Entity_Id;
2399
2400   begin
2401      Set_Msg_Blank;
2402
2403      if Error_Msg_Node_1 = Standard_Void_Type then
2404         Set_Msg_Str ("package or procedure name");
2405         return;
2406
2407      elsif Error_Msg_Node_1 = Standard_Exception_Type then
2408         Set_Msg_Str ("exception name");
2409         return;
2410
2411      elsif     Error_Msg_Node_1 = Any_Access
2412        or else Error_Msg_Node_1 = Any_Array
2413        or else Error_Msg_Node_1 = Any_Boolean
2414        or else Error_Msg_Node_1 = Any_Character
2415        or else Error_Msg_Node_1 = Any_Composite
2416        or else Error_Msg_Node_1 = Any_Discrete
2417        or else Error_Msg_Node_1 = Any_Fixed
2418        or else Error_Msg_Node_1 = Any_Integer
2419        or else Error_Msg_Node_1 = Any_Modular
2420        or else Error_Msg_Node_1 = Any_Numeric
2421        or else Error_Msg_Node_1 = Any_Real
2422        or else Error_Msg_Node_1 = Any_Scalar
2423        or else Error_Msg_Node_1 = Any_String
2424      then
2425         Get_Unqualified_Decoded_Name_String (Chars (Error_Msg_Node_1));
2426         Set_Msg_Name_Buffer;
2427         return;
2428
2429      elsif Error_Msg_Node_1 = Universal_Real then
2430         Set_Msg_Str ("type universal real");
2431         return;
2432
2433      elsif Error_Msg_Node_1 = Universal_Integer then
2434         Set_Msg_Str ("type universal integer");
2435         return;
2436
2437      elsif Error_Msg_Node_1 = Universal_Fixed then
2438         Set_Msg_Str ("type universal fixed");
2439         return;
2440      end if;
2441
2442      --  Special case of anonymous array
2443
2444      if Nkind (Error_Msg_Node_1) in N_Entity
2445        and then Is_Array_Type (Error_Msg_Node_1)
2446        and then Present (Related_Array_Object (Error_Msg_Node_1))
2447      then
2448         Set_Msg_Str ("type of ");
2449         Set_Msg_Node (Related_Array_Object (Error_Msg_Node_1));
2450         Set_Msg_Str (" declared");
2451         Set_Msg_Insertion_Line_Number
2452           (Sloc (Related_Array_Object (Error_Msg_Node_1)), Flag);
2453         return;
2454      end if;
2455
2456      --  If we fall through, it is not a special case, so first output
2457      --  the name of the type, preceded by private for a private type
2458
2459      if Is_Private_Type (Error_Msg_Node_1) then
2460         Set_Msg_Str ("private type ");
2461      else
2462         Set_Msg_Str ("type ");
2463      end if;
2464
2465      Ent := Error_Msg_Node_1;
2466
2467      if Is_Internal_Name (Chars (Ent)) then
2468         Unwind_Internal_Type (Ent);
2469      end if;
2470
2471      --  Types in Standard are displayed as "Standard.name"
2472
2473      if Sloc (Ent) <= Standard_Location then
2474         Set_Msg_Quote;
2475         Set_Msg_Str ("Standard.");
2476         Set_Msg_Node (Ent);
2477         Add_Class;
2478         Set_Msg_Quote;
2479
2480      --  Types in other language defined units are displayed as
2481      --  "package-name.type-name"
2482
2483      elsif
2484        Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (Ent)))
2485      then
2486         Get_Unqualified_Decoded_Name_String
2487           (Unit_Name (Get_Source_Unit (Ent)));
2488         Name_Len := Name_Len - 2;
2489         Set_Msg_Blank_Conditional;
2490         Set_Msg_Quote;
2491         Set_Casing (Mixed_Case);
2492         Set_Msg_Name_Buffer;
2493         Set_Msg_Char ('.');
2494         Set_Casing (Mixed_Case);
2495         Set_Msg_Node (Ent);
2496         Add_Class;
2497         Set_Msg_Quote;
2498
2499      --  All other types display as "type name" defined at line xxx
2500      --  possibly qualified if qualification is requested.
2501
2502      else
2503         Set_Msg_Quote;
2504         Set_Qualification (Error_Msg_Qual_Level, Ent);
2505         Set_Msg_Node (Ent);
2506         Add_Class;
2507
2508         --  If we did not print a name (e.g. in the case of an anonymous
2509         --  subprogram type), there is no name to print, so remove quotes.
2510
2511         if Buffer_Ends_With ('"') then
2512            Buffer_Remove ('"');
2513         else
2514            Set_Msg_Quote;
2515         end if;
2516      end if;
2517
2518      --  If the original type did not come from a predefined file, add the
2519      --  location where the type was defined.
2520
2521      if Sloc (Error_Msg_Node_1) > Standard_Location
2522        and then
2523          not Is_Predefined_File_Name
2524                (Unit_File_Name (Get_Source_Unit (Error_Msg_Node_1)))
2525      then
2526         Set_Msg_Str (" defined");
2527         Set_Msg_Insertion_Line_Number (Sloc (Error_Msg_Node_1), Flag);
2528
2529      --  If it did come from a predefined file, deal with the case where
2530      --  this was a file with a generic instantiation from elsewhere.
2531
2532      else
2533         if Sloc (Error_Msg_Node_1) > Standard_Location then
2534            declare
2535               Iloc : constant Source_Ptr :=
2536                 Instantiation_Location (Sloc (Error_Msg_Node_1));
2537
2538            begin
2539               if Iloc /= No_Location
2540                 and then not Suppress_Instance_Location
2541               then
2542                  Set_Msg_Str (" from instance");
2543                  Set_Msg_Insertion_Line_Number (Iloc, Flag);
2544               end if;
2545            end;
2546         end if;
2547      end if;
2548   end Set_Msg_Insertion_Type_Reference;
2549
2550   ---------------------------------
2551   -- Set_Msg_Insertion_Unit_Name --
2552   ---------------------------------
2553
2554   procedure Set_Msg_Insertion_Unit_Name (Suffix : Boolean := True) is
2555   begin
2556      if Error_Msg_Unit_1 = No_Unit_Name then
2557         null;
2558
2559      elsif Error_Msg_Unit_1 = Error_Unit_Name then
2560         Set_Msg_Blank;
2561         Set_Msg_Str ("<error>");
2562
2563      else
2564         Get_Unit_Name_String (Error_Msg_Unit_1, Suffix);
2565         Set_Msg_Blank;
2566         Set_Msg_Quote;
2567         Set_Msg_Name_Buffer;
2568         Set_Msg_Quote;
2569      end if;
2570
2571      --  The following assignment ensures that a second percent insertion
2572      --  character will correspond to the Error_Msg_Unit_2 parameter. We
2573      --  suppress possible validity checks in case operating in -gnatVa mode,
2574      --  and Error_Msg_Unit_2 is not needed and has not been set.
2575
2576      declare
2577         pragma Suppress (Range_Check);
2578      begin
2579         Error_Msg_Unit_1 := Error_Msg_Unit_2;
2580      end;
2581   end Set_Msg_Insertion_Unit_Name;
2582
2583   ------------------
2584   -- Set_Msg_Node --
2585   ------------------
2586
2587   procedure Set_Msg_Node (Node : Node_Id) is
2588      Ent : Entity_Id;
2589      Nam : Name_Id;
2590
2591   begin
2592      case Nkind (Node) is
2593         when N_Designator =>
2594            Set_Msg_Node (Name (Node));
2595            Set_Msg_Char ('.');
2596            Set_Msg_Node (Identifier (Node));
2597            return;
2598
2599         when N_Defining_Program_Unit_Name =>
2600            Set_Msg_Node (Name (Node));
2601            Set_Msg_Char ('.');
2602            Set_Msg_Node (Defining_Identifier (Node));
2603            return;
2604
2605         when N_Selected_Component | N_Expanded_Name =>
2606            Set_Msg_Node (Prefix (Node));
2607            Set_Msg_Char ('.');
2608            Set_Msg_Node (Selector_Name (Node));
2609            return;
2610
2611         when others =>
2612            null;
2613      end case;
2614
2615      --  The only remaining possibilities are identifiers, defining
2616      --  identifiers, pragmas, and pragma argument associations.
2617
2618      if Nkind (Node) = N_Pragma then
2619         Nam := Pragma_Name (Node);
2620
2621      --  The other cases have Chars fields, and we want to test for possible
2622      --  internal names, which generally represent something gone wrong. An
2623      --  exception is the case of internal type names, where we try to find a
2624      --  reasonable external representation for the external name
2625
2626      elsif Is_Internal_Name (Chars (Node))
2627        and then
2628          ((Is_Entity_Name (Node)
2629                          and then Present (Entity (Node))
2630                          and then Is_Type (Entity (Node)))
2631              or else
2632           (Nkind (Node) = N_Defining_Identifier and then Is_Type (Node)))
2633      then
2634         if Nkind (Node) = N_Identifier then
2635            Ent := Entity (Node);
2636         else
2637            Ent := Node;
2638         end if;
2639
2640         --  If the type is the designated type of an access_to_subprogram,
2641         --  then there is no name to provide in the call.
2642
2643         if Ekind (Ent) = E_Subprogram_Type then
2644            return;
2645
2646         --  Otherwise, we will be able to find some kind of name to output
2647
2648         else
2649            Unwind_Internal_Type (Ent);
2650            Nam := Chars (Ent);
2651         end if;
2652
2653      --  If not internal name, just use name in Chars field
2654
2655      else
2656         Nam := Chars (Node);
2657      end if;
2658
2659      --  At this stage, the name to output is in Nam
2660
2661      Get_Unqualified_Decoded_Name_String (Nam);
2662
2663      --  Remove trailing upper case letters from the name (useful for
2664      --  dealing with some cases of internal names.
2665
2666      while Name_Len > 1 and then Name_Buffer (Name_Len) in 'A' .. 'Z' loop
2667         Name_Len := Name_Len  - 1;
2668      end loop;
2669
2670      --  If we have any of the names from standard that start with the
2671      --  characters "any " (e.g. Any_Type), then kill the message since
2672      --  almost certainly it is a junk cascaded message.
2673
2674      if Name_Len > 4
2675        and then Name_Buffer (1 .. 4) = "any "
2676      then
2677         Kill_Message := True;
2678      end if;
2679
2680      --  Now we have to set the proper case. If we have a source location
2681      --  then do a check to see if the name in the source is the same name
2682      --  as the name in the Names table, except for possible differences
2683      --  in case, which is the case when we can copy from the source.
2684
2685      declare
2686         Src_Loc : constant Source_Ptr := Sloc (Node);
2687         Sbuffer : Source_Buffer_Ptr;
2688         Ref_Ptr : Integer;
2689         Src_Ptr : Source_Ptr;
2690
2691      begin
2692         Ref_Ptr := 1;
2693         Src_Ptr := Src_Loc;
2694
2695         --  For standard locations, always use mixed case
2696
2697         if Src_Loc <= No_Location
2698           or else Sloc (Node) <= No_Location
2699         then
2700            Set_Casing (Mixed_Case);
2701
2702         else
2703            --  Determine if the reference we are dealing with corresponds to
2704            --  text at the point of the error reference. This will often be
2705            --  the case for simple identifier references, and is the case
2706            --  where we can copy the spelling from the source.
2707
2708            Sbuffer := Source_Text (Get_Source_File_Index (Src_Loc));
2709
2710            while Ref_Ptr <= Name_Len loop
2711               exit when
2712                 Fold_Lower (Sbuffer (Src_Ptr)) /=
2713                 Fold_Lower (Name_Buffer (Ref_Ptr));
2714               Ref_Ptr := Ref_Ptr + 1;
2715               Src_Ptr := Src_Ptr + 1;
2716            end loop;
2717
2718            --  If we get through the loop without a mismatch, then output the
2719            --  name the way it is spelled in the source program
2720
2721            if Ref_Ptr > Name_Len then
2722               Src_Ptr := Src_Loc;
2723
2724               for J in 1 .. Name_Len loop
2725                  Name_Buffer (J) := Sbuffer (Src_Ptr);
2726                  Src_Ptr := Src_Ptr + 1;
2727               end loop;
2728
2729            --  Otherwise set the casing using the default identifier casing
2730
2731            else
2732               Set_Casing (Identifier_Casing (Flag_Source), Mixed_Case);
2733            end if;
2734         end if;
2735      end;
2736
2737      Set_Msg_Name_Buffer;
2738      Add_Class;
2739   end Set_Msg_Node;
2740
2741   ------------------
2742   -- Set_Msg_Text --
2743   ------------------
2744
2745   procedure Set_Msg_Text (Text : String; Flag : Source_Ptr) is
2746      C : Character;   -- Current character
2747      P : Natural;     -- Current index;
2748
2749      procedure Set_Msg_Insertion_Warning (C : Character);
2750      --  Deal with ? ?? ?x? ?X? insertion sequences (also < << <x< <X<). The
2751      --  caller has already bumped the pointer past the initial ? or < and C
2752      --  is set to this initial character (? or <).
2753
2754      -------------------------------
2755      -- Set_Msg_Insertion_Warning --
2756      -------------------------------
2757
2758      procedure Set_Msg_Insertion_Warning (C : Character) is
2759      begin
2760         if P <= Text'Last and then Text (P) = C then
2761            Warning_Msg_Char := '?';
2762            P := P + 1;
2763
2764         elsif P + 1 <= Text'Last
2765           and then (Text (P) in 'a' .. 'z'
2766                       or else
2767                     Text (P) in 'A' .. 'Z')
2768           and then Text (P + 1) = C
2769         then
2770            Warning_Msg_Char := Text (P);
2771            P := P + 2;
2772         else
2773            Warning_Msg_Char := ' ';
2774         end if;
2775      end Set_Msg_Insertion_Warning;
2776
2777   --  Start of processing for Set_Msg_Text
2778
2779   begin
2780      Manual_Quote_Mode := False;
2781      Msglen := 0;
2782      Flag_Source := Get_Source_File_Index (Flag);
2783
2784      P := Text'First;
2785      while P <= Text'Last loop
2786         C := Text (P);
2787         P := P + 1;
2788
2789         --  Check for insertion character or sequence
2790
2791         case C is
2792            when '%' =>
2793               if P <= Text'Last and then Text (P) = '%' then
2794                  P := P + 1;
2795                  Set_Msg_Insertion_Name_Literal;
2796               else
2797                  Set_Msg_Insertion_Name;
2798               end if;
2799
2800            when '$' =>
2801               if P <= Text'Last and then Text (P) = '$' then
2802                  P := P + 1;
2803                  Set_Msg_Insertion_Unit_Name (Suffix => False);
2804               else
2805                  Set_Msg_Insertion_Unit_Name;
2806               end if;
2807
2808            when '{' =>
2809               Set_Msg_Insertion_File_Name;
2810
2811            when '}' =>
2812               Set_Msg_Insertion_Type_Reference (Flag);
2813
2814            when '*' =>
2815               Set_Msg_Insertion_Reserved_Name;
2816
2817            when '&' =>
2818               Set_Msg_Insertion_Node;
2819
2820            when '#' =>
2821               Set_Msg_Insertion_Line_Number (Error_Msg_Sloc, Flag);
2822
2823            when '\' =>
2824               Continuation := True;
2825
2826               if Text (P) = '\' then
2827                  Continuation_New_Line := True;
2828                  P := P + 1;
2829               end if;
2830
2831            when '@' =>
2832               Set_Msg_Insertion_Column;
2833
2834            when '>' =>
2835               Set_Msg_Insertion_Run_Time_Name;
2836
2837            when '^' =>
2838               Set_Msg_Insertion_Uint;
2839
2840            when '`' =>
2841               Manual_Quote_Mode := not Manual_Quote_Mode;
2842               Set_Msg_Char ('"');
2843
2844            when '!' =>
2845               null; -- already dealt with
2846
2847            when '?' =>
2848               Set_Msg_Insertion_Warning ('?');
2849
2850            when '<' =>
2851
2852               --  Note: the prescan already set Is_Warning_Msg True if and
2853               --  only if Error_Msg_Warn is set to True. If Error_Msg_Warn
2854               --  is False, the call to Set_Msg_Insertion_Warning here does
2855               --  no harm, since Warning_Msg_Char is ignored in that case.
2856
2857               Set_Msg_Insertion_Warning ('<');
2858
2859            when '|' =>
2860               null; -- already dealt with
2861
2862            when ''' =>
2863               Set_Msg_Char (Text (P));
2864               P := P + 1;
2865
2866            when '~' =>
2867               Set_Msg_Str (Error_Msg_String (1 .. Error_Msg_Strlen));
2868
2869            --  Upper case letter
2870
2871            when 'A' .. 'Z' =>
2872
2873               --  Start of reserved word if two or more
2874
2875               if P <= Text'Last and then Text (P) in 'A' .. 'Z' then
2876                  P := P - 1;
2877                  Set_Msg_Insertion_Reserved_Word (Text, P);
2878
2879               --  Single upper case letter is just inserted
2880
2881               else
2882                  Set_Msg_Char (C);
2883               end if;
2884
2885            --  '[' (will be/would have been raised at run time)
2886
2887            when '[' =>
2888               if Is_Warning_Msg then
2889                  Set_Msg_Str ("will be raised at run time");
2890               else
2891                  Set_Msg_Str ("would have been raised at run time");
2892               end if;
2893
2894            --   ']' (may be/might have been raised at run time)
2895
2896            when ']' =>
2897               if Is_Warning_Msg then
2898                  Set_Msg_Str ("may be raised at run time");
2899               else
2900                  Set_Msg_Str ("might have been raised at run time");
2901               end if;
2902
2903            --  Normal character with no special treatment
2904
2905            when others =>
2906               Set_Msg_Char (C);
2907         end case;
2908      end loop;
2909
2910      VMS_Convert;
2911   end Set_Msg_Text;
2912
2913   ----------------
2914   -- Set_Posted --
2915   ----------------
2916
2917   procedure Set_Posted (N : Node_Id) is
2918      P : Node_Id;
2919
2920   begin
2921      if Is_Serious_Error then
2922
2923         --  We always set Error_Posted on the node itself
2924
2925         Set_Error_Posted (N);
2926
2927         --  If it is a subexpression, then set Error_Posted on parents up to
2928         --  and including the first non-subexpression construct. This helps
2929         --  avoid cascaded error messages within a single expression.
2930
2931         P := N;
2932         loop
2933            P := Parent (P);
2934            exit when No (P);
2935            Set_Error_Posted (P);
2936            exit when Nkind (P) not in N_Subexpr;
2937         end loop;
2938
2939         --  A special check, if we just posted an error on an attribute
2940         --  definition clause, then also set the entity involved as posted.
2941         --  For example, this stops complaining about the alignment after
2942         --  complaining about the size, which is likely to be useless.
2943
2944         if Nkind (P) = N_Attribute_Definition_Clause then
2945            if Is_Entity_Name (Name (P)) then
2946               Set_Error_Posted (Entity (Name (P)));
2947            end if;
2948         end if;
2949      end if;
2950   end Set_Posted;
2951
2952   -----------------------
2953   -- Set_Qualification --
2954   -----------------------
2955
2956   procedure Set_Qualification (N : Nat; E : Entity_Id) is
2957   begin
2958      if N /= 0 and then Scope (E) /= Standard_Standard then
2959         Set_Qualification (N - 1, Scope (E));
2960         Set_Msg_Node (Scope (E));
2961         Set_Msg_Char ('.');
2962      end if;
2963   end Set_Qualification;
2964
2965   ------------------------
2966   -- Special_Msg_Delete --
2967   ------------------------
2968
2969   --  Is it really right to have all this specialized knowledge in errout?
2970
2971   function Special_Msg_Delete
2972     (Msg : String;
2973      N   : Node_Or_Entity_Id;
2974      E   : Node_Or_Entity_Id) return Boolean
2975   is
2976   begin
2977      --  Never delete messages in -gnatdO mode
2978
2979      if Debug_Flag_OO then
2980         return False;
2981
2982      --  Processing for "atomic access cannot be guaranteed"
2983
2984      elsif Msg = "atomic access to & cannot be guaranteed" then
2985
2986         --  When an atomic object refers to a non-atomic type in the same
2987         --  scope, we implicitly make the type atomic. In the non-error case
2988         --  this is surely safe (and in fact prevents an error from occurring
2989         --  if the type is not atomic by default). But if the object cannot be
2990         --  made atomic, then we introduce an extra junk message by this
2991         --  manipulation, which we get rid of here.
2992
2993         --  We identify this case by the fact that it references a type for
2994         --  which Is_Atomic is set, but there is no Atomic pragma setting it.
2995
2996         if Is_Type (E)
2997           and then Is_Atomic (E)
2998           and then No (Get_Rep_Pragma (E, Name_Atomic))
2999         then
3000            return True;
3001         end if;
3002
3003      --  Processing for "Size too small" messages
3004
3005      elsif Msg = "size for& too small, minimum allowed is ^" then
3006
3007         --  Suppress "size too small" errors in CodePeer mode, since code may
3008         --  be analyzed in a different configuration than the one used for
3009         --  compilation. Even when the configurations match, this message
3010         --  may be issued on correct code, because pragma Pack is ignored
3011         --  in CodePeer mode.
3012
3013         if CodePeer_Mode then
3014            return True;
3015
3016         --  When a size is wrong for a frozen type there is no explicit size
3017         --  clause, and other errors have occurred, suppress the message,
3018         --  since it is likely that this size error is a cascaded result of
3019         --  other errors. The reason we eliminate unfrozen types is that
3020         --  messages issued before the freeze type are for sure OK.
3021
3022         elsif Is_Frozen (E)
3023           and then Serious_Errors_Detected > 0
3024           and then Nkind (N) /= N_Component_Clause
3025           and then Nkind (Parent (N)) /= N_Component_Clause
3026           and then
3027             No (Get_Attribute_Definition_Clause (E, Attribute_Size))
3028           and then
3029             No (Get_Attribute_Definition_Clause (E, Attribute_Object_Size))
3030           and then
3031             No (Get_Attribute_Definition_Clause (E, Attribute_Value_Size))
3032         then
3033            return True;
3034         end if;
3035      end if;
3036
3037      --  All special tests complete, so go ahead with message
3038
3039      return False;
3040   end Special_Msg_Delete;
3041
3042   --------------------------
3043   -- Unwind_Internal_Type --
3044   --------------------------
3045
3046   procedure Unwind_Internal_Type (Ent : in out Entity_Id) is
3047      Derived : Boolean := False;
3048      Mchar   : Character;
3049      Old_Ent : Entity_Id;
3050
3051   begin
3052      --  Undo placement of a quote, since we will put it back later
3053
3054      Mchar := Msg_Buffer (Msglen);
3055
3056      if Mchar = '"' then
3057         Msglen := Msglen - 1;
3058      end if;
3059
3060      --  The loop here deals with recursive types, we are trying to find a
3061      --  related entity that is not an implicit type. Note that the check with
3062      --  Old_Ent stops us from getting "stuck". Also, we don't output the
3063      --  "type derived from" message more than once in the case where we climb
3064      --  up multiple levels.
3065
3066      Find : loop
3067         Old_Ent := Ent;
3068
3069         --  Implicit access type, use directly designated type In Ada 2005,
3070         --  the designated type may be an anonymous access to subprogram, in
3071         --  which case we can only point to its definition.
3072
3073         if Is_Access_Type (Ent) then
3074            if Ekind (Ent) = E_Access_Subprogram_Type
3075              or else Ekind (Ent) = E_Anonymous_Access_Subprogram_Type
3076              or else Is_Access_Protected_Subprogram_Type (Ent)
3077            then
3078               Ent := Directly_Designated_Type (Ent);
3079
3080               if not Comes_From_Source (Ent) then
3081                  if Buffer_Ends_With ("type ") then
3082                     Buffer_Remove ("type ");
3083                  end if;
3084               end if;
3085
3086               if Ekind (Ent) = E_Function then
3087                  Set_Msg_Str ("access to function ");
3088               elsif Ekind (Ent) = E_Procedure then
3089                  Set_Msg_Str ("access to procedure ");
3090               else
3091                  Set_Msg_Str ("access to subprogram");
3092               end if;
3093
3094               exit Find;
3095
3096            --  Type is access to object, named or anonymous
3097
3098            else
3099               Set_Msg_Str ("access to ");
3100               Ent := Directly_Designated_Type (Ent);
3101            end if;
3102
3103         --  Classwide type
3104
3105         elsif Is_Class_Wide_Type (Ent) then
3106            Class_Flag := True;
3107            Ent := Root_Type (Ent);
3108
3109         --  Use base type if this is a subtype
3110
3111         elsif Ent /= Base_Type (Ent) then
3112            Buffer_Remove ("type ");
3113
3114            --  Avoid duplication "subtype of subtype of", and also replace
3115            --  "derived from subtype of" simply by "derived from"
3116
3117            if not Buffer_Ends_With ("subtype of ")
3118              and then not Buffer_Ends_With ("derived from ")
3119            then
3120               Set_Msg_Str ("subtype of ");
3121            end if;
3122
3123            Ent := Base_Type (Ent);
3124
3125         --  If this is a base type with a first named subtype, use the first
3126         --  named subtype instead. This is not quite accurate in all cases,
3127         --  but it makes too much noise to be accurate and add 'Base in all
3128         --  cases. Note that we only do this is the first named subtype is not
3129         --  itself an internal name. This avoids the obvious loop (subtype ->
3130         --  basetype -> subtype) which would otherwise occur).
3131
3132         else
3133            declare
3134               FST : constant Entity_Id := First_Subtype (Ent);
3135
3136            begin
3137               if not Is_Internal_Name (Chars (FST)) then
3138                  Ent := FST;
3139                  exit Find;
3140
3141                  --  Otherwise use root type
3142
3143               else
3144                  if not Derived then
3145                     Buffer_Remove ("type ");
3146
3147                     --  Test for "subtype of type derived from" which seems
3148                     --  excessive and is replaced by "type derived from".
3149
3150                     Buffer_Remove ("subtype of");
3151
3152                     --  Avoid duplicated "type derived from type derived from"
3153
3154                     if not Buffer_Ends_With ("type derived from ") then
3155                        Set_Msg_Str ("type derived from ");
3156                     end if;
3157
3158                     Derived := True;
3159                  end if;
3160               end if;
3161            end;
3162
3163            Ent := Etype (Ent);
3164         end if;
3165
3166         --  If we are stuck in a loop, get out and settle for the internal
3167         --  name after all. In this case we set to kill the message if it is
3168         --  not the first error message (we really try hard not to show the
3169         --  dirty laundry of the implementation to the poor user).
3170
3171         if Ent = Old_Ent then
3172            Kill_Message := True;
3173            exit Find;
3174         end if;
3175
3176         --  Get out if we finally found a non-internal name to use
3177
3178         exit Find when not Is_Internal_Name (Chars (Ent));
3179      end loop Find;
3180
3181      if Mchar = '"' then
3182         Set_Msg_Char ('"');
3183      end if;
3184   end Unwind_Internal_Type;
3185
3186   -----------------
3187   -- VMS_Convert --
3188   -----------------
3189
3190   procedure VMS_Convert is
3191      P : Natural;
3192      L : Natural;
3193      N : Natural;
3194
3195   begin
3196      if not OpenVMS then
3197         return;
3198      end if;
3199
3200      P := Msg_Buffer'First;
3201      loop
3202         if P >= Msglen then
3203            return;
3204         end if;
3205
3206         if Msg_Buffer (P) = '-' then
3207            for G in Gnames'Range loop
3208               L := Gnames (G)'Length;
3209
3210               --  See if we have "-ggg switch", where ggg is Gnames entry
3211
3212               if P + L + 7 <= Msglen
3213                 and then Msg_Buffer (P + 1 .. P + L) = Gnames (G).all
3214                 and then Msg_Buffer (P + L + 1 .. P + L + 7) = " switch"
3215               then
3216                  --  Replace by "/vvv qualifier", where vvv is Vnames entry
3217
3218                  N := Vnames (G)'Length;
3219                  Msg_Buffer (P + N + 11 .. Msglen + N - L + 3) :=
3220                    Msg_Buffer (P + L + 8 .. Msglen);
3221                  Msg_Buffer (P) := '/';
3222                  Msg_Buffer (P + 1 .. P + N) := Vnames (G).all;
3223                  Msg_Buffer (P + N + 1 .. P + N + 10) := " qualifier";
3224                  P := P + N + 10;
3225                  Msglen := Msglen + N - L + 3;
3226                  exit;
3227               end if;
3228            end loop;
3229         end if;
3230
3231         P := P + 1;
3232      end loop;
3233   end VMS_Convert;
3234
3235end Errout;
3236