1------------------------------------------------------------------------------
2--                                                                          --
3--                         GNAT COMPILER COMPONENTS                         --
4--                                                                          --
5--                               E R R O U T                                --
6--                                                                          --
7--                                 B o d y                                  --
8--                                                                          --
9--          Copyright (C) 1992-2015, 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 Lib;      use Lib;
41with Opt;      use Opt;
42with Nlists;   use Nlists;
43with Output;   use Output;
44with Scans;    use Scans;
45with Sem_Aux;  use Sem_Aux;
46with Sinput;   use Sinput;
47with Sinfo;    use Sinfo;
48with Snames;   use Snames;
49with Stand;    use Stand;
50with Stylesw;  use Stylesw;
51with Uname;    use Uname;
52
53package body Errout is
54
55   Errors_Must_Be_Ignored : Boolean := False;
56   --  Set to True by procedure Set_Ignore_Errors (True), when calls to error
57   --  message procedures should be ignored (when parsing irrelevant text in
58   --  sources being preprocessed).
59
60   Finalize_Called : Boolean := False;
61   --  Set True if the Finalize routine has been called
62
63   Warn_On_Instance : Boolean;
64   --  Flag set true for warning message to be posted on instance
65
66   ------------------------------------
67   -- Table of Non-Instance Messages --
68   ------------------------------------
69
70   --  This table contains an entry for every error message processed by the
71   --  Error_Msg routine that is not posted on generic (or inlined) instance.
72   --  As explained in further detail in the Error_Msg procedure body, this
73   --  table is used to avoid posting redundant messages on instances.
74
75   type NIM_Record is record
76      Msg : String_Ptr;
77      Loc : Source_Ptr;
78   end record;
79   --  Type used to store text and location of one message
80
81   package Non_Instance_Msgs is new Table.Table (
82     Table_Component_Type => NIM_Record,
83     Table_Index_Type     => Int,
84     Table_Low_Bound      => 1,
85     Table_Initial        => 100,
86     Table_Increment      => 100,
87     Table_Name           => "Non_Instance_Msgs");
88
89   -----------------------
90   -- Local Subprograms --
91   -----------------------
92
93   procedure Error_Msg_Internal
94     (Msg      : String;
95      Sptr     : Source_Ptr;
96      Optr     : Source_Ptr;
97      Msg_Cont : Boolean);
98   --  This is the low level routine used to post messages after dealing with
99   --  the issue of messages placed on instantiations (which get broken up
100   --  into separate calls in Error_Msg). Sptr is the location on which the
101   --  flag will be placed in the output. In the case where the flag is on
102   --  the template, this points directly to the template, not to one of the
103   --  instantiation copies of the template. Optr is the original location
104   --  used to flag the error, and this may indeed point to an instantiation
105   --  copy. So typically we can see Optr pointing to the template location
106   --  in an instantiation copy when Sptr points to the source location of
107   --  the actual instantiation (i.e the line with the new). Msg_Cont is
108   --  set true if this is a continuation message.
109
110   function No_Warnings (N : Node_Or_Entity_Id) return Boolean;
111   --  Determines if warnings should be suppressed for the given node
112
113   function OK_Node (N : Node_Id) return Boolean;
114   --  Determines if a node is an OK node to place an error message on (return
115   --  True) or if the error message should be suppressed (return False). A
116   --  message is suppressed if the node already has an error posted on it,
117   --  or if it refers to an Etype that has an error posted on it, or if
118   --  it references an Entity that has an error posted on it.
119
120   procedure Output_Source_Line
121     (L     : Physical_Line_Number;
122      Sfile : Source_File_Index;
123      Errs  : Boolean);
124   --  Outputs text of source line L, in file S, together with preceding line
125   --  number, as described above for Output_Line_Number. The Errs parameter
126   --  indicates if there are errors attached to the line, which forces
127   --  listing on, even in the presence of pragma List (Off).
128
129   procedure Set_Msg_Insertion_Column;
130   --  Handle column number insertion (@ insertion character)
131
132   procedure Set_Msg_Insertion_Node;
133   --  Handle node (name from node) insertion (& insertion character)
134
135   procedure Set_Msg_Insertion_Type_Reference (Flag : Source_Ptr);
136   --  Handle type reference (right brace insertion character). Flag is the
137   --  location of the flag, which is provided for the internal call to
138   --  Set_Msg_Insertion_Line_Number,
139
140   procedure Set_Msg_Insertion_Unit_Name (Suffix : Boolean := True);
141   --  Handle unit name insertion ($ insertion character). Depending on Boolean
142   --  parameter Suffix, (spec) or (body) is appended after the unit name.
143
144   procedure Set_Msg_Node (Node : Node_Id);
145   --  Add the sequence of characters for the name associated with the given
146   --  node to the current message. For N_Designator, N_Selected_Component,
147   --  N_Defining_Program_Unit_Name, and N_Expanded_Name, the Prefix is
148   --  included as well.
149
150   procedure Set_Msg_Text (Text : String; Flag : Source_Ptr);
151   --  Add a sequence of characters to the current message. The characters may
152   --  be one of the special insertion characters (see documentation in spec).
153   --  Flag is the location at which the error is to be posted, which is used
154   --  to determine whether or not the # insertion needs a file name. The
155   --  variables Msg_Buffer are set on return Msglen.
156
157   procedure Set_Posted (N : Node_Id);
158   --  Sets the Error_Posted flag on the given node, and all its parents that
159   --  are subexpressions and then on the parent non-subexpression construct
160   --  that contains the original expression. If that parent is a named
161   --  association, the flag is further propagated to its parent. This is done
162   --  in order to guard against cascaded errors. Note that this call has an
163   --  effect for a serious error only.
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   function Warn_Insertion return String;
193   --  This is called for warning messages only (so Warning_Msg_Char is set)
194   --  and returns a corresponding string to use at the beginning of generated
195   --  auxiliary messages, such as "in instantiation at ...".
196   --    'a' .. 'z'   returns "?x?"
197   --    'A' .. 'Z'   returns "?X?"
198   --    '*'          returns "?*?"
199   --    '$'          returns "?$?info: "
200   --    ' '          returns " "
201   --  No other settings are valid
202
203   -----------------------
204   -- Change_Error_Text --
205   -----------------------
206
207   procedure Change_Error_Text (Error_Id : Error_Msg_Id; New_Msg : String) is
208      Save_Next : Error_Msg_Id;
209      Err_Id    : Error_Msg_Id := Error_Id;
210
211   begin
212      Set_Msg_Text (New_Msg, Errors.Table (Error_Id).Sptr);
213      Errors.Table (Error_Id).Text := new String'(Msg_Buffer (1 .. Msglen));
214
215      --  If in immediate error message mode, output modified error message now
216      --  This is just a bit tricky, because we want to output just a single
217      --  message, and the messages we modified is already linked in. We solve
218      --  this by temporarily resetting its forward pointer to empty.
219
220      if Debug_Flag_OO then
221         Save_Next := Errors.Table (Error_Id).Next;
222         Errors.Table (Error_Id).Next := No_Error_Msg;
223         Write_Eol;
224         Output_Source_Line
225           (Errors.Table (Error_Id).Line, Errors.Table (Error_Id).Sfile, True);
226         Output_Error_Msgs (Err_Id);
227         Errors.Table (Error_Id).Next := Save_Next;
228      end if;
229   end Change_Error_Text;
230
231   ------------------------
232   -- Compilation_Errors --
233   ------------------------
234
235   function Compilation_Errors return Boolean is
236   begin
237      if not Finalize_Called then
238         raise Program_Error;
239      else
240         return Erroutc.Compilation_Errors;
241      end if;
242   end Compilation_Errors;
243
244   --------------------------------------
245   -- Delete_Warning_And_Continuations --
246   --------------------------------------
247
248   procedure Delete_Warning_And_Continuations (Msg : Error_Msg_Id) is
249      Id : Error_Msg_Id;
250
251   begin
252      pragma Assert (not Errors.Table (Msg).Msg_Cont);
253
254      Id := Msg;
255      loop
256         declare
257            M : Error_Msg_Object renames Errors.Table (Id);
258
259         begin
260            if not M.Deleted then
261               M.Deleted := True;
262               Warnings_Detected := Warnings_Detected - 1;
263
264               if M.Info then
265                  Info_Messages := Info_Messages - 1;
266               end if;
267
268               if M.Warn_Err then
269                  Warnings_Treated_As_Errors := Warnings_Treated_As_Errors - 1;
270               end if;
271            end if;
272
273            Id := M.Next;
274            exit when Id = No_Error_Msg;
275            exit when not Errors.Table (Id).Msg_Cont;
276         end;
277      end loop;
278   end Delete_Warning_And_Continuations;
279
280   ---------------
281   -- Error_Msg --
282   ---------------
283
284   --  Error_Msg posts a flag at the given location, except that if the
285   --  Flag_Location points within a generic template and corresponds to an
286   --  instantiation of this generic template, then the actual message will be
287   --  posted on the generic instantiation, along with additional messages
288   --  referencing the generic declaration.
289
290   procedure Error_Msg (Msg : String; Flag_Location : Source_Ptr) is
291      Sindex : Source_File_Index;
292      --  Source index for flag location
293
294      Orig_Loc : Source_Ptr;
295      --  Original location of Flag_Location (i.e. location in original
296      --  template in instantiation case, otherwise unchanged).
297
298   begin
299      --  It is a fatal error to issue an error message when scanning from the
300      --  internal source buffer (see Sinput for further documentation)
301
302      pragma Assert (Sinput.Source /= Internal_Source_Ptr);
303
304      --  Return if all errors are to be ignored
305
306      if Errors_Must_Be_Ignored then
307         return;
308      end if;
309
310      --  If we already have messages, and we are trying to place a message at
311      --  No_Location, then just ignore the attempt since we assume that what
312      --  is happening is some cascaded junk. Note that this is safe in the
313      --  sense that proceeding will surely bomb. We will also bomb if the flag
314      --  location is No_Location and we don't have any messages so far, but
315      --  that is a real bug and a legitimate bomb, so we go ahead.
316
317      if Flag_Location = No_Location
318        and then Total_Errors_Detected > 0
319      then
320         return;
321      end if;
322
323      --  Start of processing for new message
324
325      Sindex := Get_Source_File_Index (Flag_Location);
326      Prescan_Message (Msg);
327      Orig_Loc := Original_Location (Flag_Location);
328
329      --  If the current location is in an instantiation, the issue arises of
330      --  whether to post the message on the template or the instantiation.
331
332      --  The way we decide is to see if we have posted the same message on
333      --  the template when we compiled the template (the template is always
334      --  compiled before any instantiations). For this purpose, we use a
335      --  separate table of messages. The reason we do this is twofold:
336
337      --     First, the messages can get changed by various processing
338      --     including the insertion of tokens etc, making it hard to
339      --     do the comparison.
340
341      --     Second, we will suppress a warning on a template if it is not in
342      --     the current extended source unit. That's reasonable and means we
343      --     don't want the warning on the instantiation here either, but it
344      --     does mean that the main error table would not in any case include
345      --     the message.
346
347      if Flag_Location = Orig_Loc then
348         Non_Instance_Msgs.Append ((new String'(Msg), Flag_Location));
349         Warn_On_Instance := False;
350
351      --  Here we have an instance message
352
353      else
354         --  Delete if debug flag off, and this message duplicates a message
355         --  already posted on the corresponding template
356
357         if not Debug_Flag_GG then
358            for J in Non_Instance_Msgs.First .. Non_Instance_Msgs.Last loop
359               if Msg = Non_Instance_Msgs.Table (J).Msg.all
360                 and then Non_Instance_Msgs.Table (J).Loc = Orig_Loc
361               then
362                  return;
363               end if;
364            end loop;
365         end if;
366
367         --  No duplicate, so error/warning will be posted on instance
368
369         Warn_On_Instance := Is_Warning_Msg;
370      end if;
371
372      --  Ignore warning message that is suppressed for this location. Note
373      --  that style checks are not considered warning messages for this
374      --  purpose.
375
376      if Is_Warning_Msg and then Warnings_Suppressed (Orig_Loc) /= No_String
377      then
378         return;
379
380      --  For style messages, check too many messages so far
381
382      elsif Is_Style_Msg
383        and then Maximum_Messages /= 0
384        and then Warnings_Detected >= Maximum_Messages
385      then
386         return;
387      end if;
388
389      --  The idea at this stage is that we have two kinds of messages
390
391      --  First, we have those messages that are to be placed as requested at
392      --  Flag_Location. This includes messages that have nothing to do with
393      --  generics, and also messages placed on generic templates that reflect
394      --  an error in the template itself. For such messages we simply call
395      --  Error_Msg_Internal to place the message in the requested location.
396
397      if Instantiation (Sindex) = No_Location then
398         Error_Msg_Internal (Msg, Flag_Location, Flag_Location, False);
399         return;
400      end if;
401
402      --  If we are trying to flag an error in an instantiation, we may have
403      --  a generic contract violation. What we generate in this case is:
404
405      --     instantiation error at ...
406      --     original error message
407
408      --  or
409
410      --     warning: in instantiation at
411      --     warning: original warning message
412
413      --  All these messages are posted at the location of the top level
414      --  instantiation. If there are nested instantiations, then the
415      --  instantiation error message can be repeated, pointing to each
416      --  of the relevant instantiations.
417
418      --  Note: the instantiation mechanism is also shared for inlining of
419      --  subprogram bodies when front end inlining is done. In this case the
420      --  messages have the form:
421
422      --     in inlined body at ...
423      --     original error message
424
425      --  or
426
427      --     warning: in inlined body at
428      --     warning: original warning message
429
430      --  OK, here we have an instantiation error, and we need to generate the
431      --  error on the instantiation, rather than on the template.
432
433      declare
434         Actual_Error_Loc : Source_Ptr;
435         --  Location of outer level instantiation in instantiation case, or
436         --  just a copy of Flag_Location in the normal case. This is the
437         --  location where all error messages will actually be posted.
438
439         Save_Error_Msg_Sloc : constant Source_Ptr := Error_Msg_Sloc;
440         --  Save possible location set for caller's message. We need to use
441         --  Error_Msg_Sloc for the location of the instantiation error but we
442         --  have to preserve a possible original value.
443
444         X : Source_File_Index;
445
446         Msg_Cont_Status : Boolean;
447         --  Used to label continuation lines in instantiation case with
448         --  proper Msg_Cont status.
449
450      begin
451         --  Loop to find highest level instantiation, where all error
452         --  messages will be placed.
453
454         X := Sindex;
455         loop
456            Actual_Error_Loc := Instantiation (X);
457            X := Get_Source_File_Index (Actual_Error_Loc);
458            exit when Instantiation (X) = No_Location;
459         end loop;
460
461         --  Since we are generating the messages at the instantiation point in
462         --  any case, we do not want the references to the bad lines in the
463         --  instance to be annotated with the location of the instantiation.
464
465         Suppress_Instance_Location := True;
466         Msg_Cont_Status := False;
467
468         --  Loop to generate instantiation messages
469
470         Error_Msg_Sloc := Flag_Location;
471         X := Get_Source_File_Index (Flag_Location);
472         while Instantiation (X) /= No_Location loop
473
474            --  Suppress instantiation message on continuation lines
475
476            if Msg (Msg'First) /= '\' then
477
478               --  Case of inlined body
479
480               if Inlined_Body (X) then
481                  if Is_Warning_Msg or Is_Style_Msg then
482                     Error_Msg_Internal
483                       (Warn_Insertion & "in inlined body #",
484                        Actual_Error_Loc, Flag_Location, Msg_Cont_Status);
485                  else
486                     Error_Msg_Internal
487                       ("error in inlined body #",
488                        Actual_Error_Loc, Flag_Location, Msg_Cont_Status);
489                  end if;
490
491               --  Case of generic instantiation
492
493               else
494                  if Is_Warning_Msg or else Is_Style_Msg then
495                     Error_Msg_Internal
496                       (Warn_Insertion & "in instantiation #",
497                        Actual_Error_Loc, Flag_Location, Msg_Cont_Status);
498                  else
499                     Error_Msg_Internal
500                       ("instantiation error #",
501                        Actual_Error_Loc, Flag_Location, Msg_Cont_Status);
502                  end if;
503               end if;
504            end if;
505
506            Error_Msg_Sloc := Instantiation (X);
507            X := Get_Source_File_Index (Error_Msg_Sloc);
508            Msg_Cont_Status := True;
509         end loop;
510
511         Suppress_Instance_Location := False;
512         Error_Msg_Sloc := Save_Error_Msg_Sloc;
513
514         --  Here we output the original message on the outer instantiation
515
516         Error_Msg_Internal
517           (Msg, Actual_Error_Loc, Flag_Location, Msg_Cont_Status);
518      end;
519   end Error_Msg;
520
521   --------------------------------
522   -- Error_Msg_Ada_2012_Feature --
523   --------------------------------
524
525   procedure Error_Msg_Ada_2012_Feature (Feature : String; Loc : Source_Ptr) is
526   begin
527      if Ada_Version < Ada_2012 then
528         Error_Msg (Feature & " is an Ada 2012 feature", Loc);
529
530         if No (Ada_Version_Pragma) then
531            Error_Msg ("\unit must be compiled with -gnat2012 switch", Loc);
532         else
533            Error_Msg_Sloc := Sloc (Ada_Version_Pragma);
534            Error_Msg ("\incompatible with Ada version set#", Loc);
535         end if;
536      end if;
537   end Error_Msg_Ada_2012_Feature;
538
539   ------------------
540   -- Error_Msg_AP --
541   ------------------
542
543   procedure Error_Msg_AP (Msg : String) is
544      S1 : Source_Ptr;
545      C  : Character;
546
547   begin
548      --  If we had saved the Scan_Ptr value after scanning the previous
549      --  token, then we would have exactly the right place for putting
550      --  the flag immediately at hand. However, that would add at least
551      --  two instructions to a Scan call *just* to service the possibility
552      --  of an Error_Msg_AP call. So instead we reconstruct that value.
553
554      --  We have two possibilities, start with Prev_Token_Ptr and skip over
555      --  the current token, which is made harder by the possibility that this
556      --  token may be in error, or start with Token_Ptr and work backwards.
557      --  We used to take the second approach, but it's hard because of
558      --  comments, and harder still because things that look like comments
559      --  can appear inside strings. So now we take the first approach.
560
561      --  Note: in the case where there is no previous token, Prev_Token_Ptr
562      --  is set to Source_First, which is a reasonable position for the
563      --  error flag in this situation.
564
565      S1 := Prev_Token_Ptr;
566      C := Source (S1);
567
568      --  If the previous token is a string literal, we need a special approach
569      --  since there may be white space inside the literal and we don't want
570      --  to stop on that white space.
571
572      --  Note: since this is an error recovery issue anyway, it is not worth
573      --  worrying about special UTF_32 line terminator characters here.
574
575      if Prev_Token = Tok_String_Literal then
576         loop
577            S1 := S1 + 1;
578
579            if Source (S1) = C then
580               S1 := S1 + 1;
581               exit when Source (S1) /= C;
582            elsif Source (S1) in Line_Terminator then
583               exit;
584            end if;
585         end loop;
586
587      --  Character literal also needs special handling
588
589      elsif Prev_Token = Tok_Char_Literal then
590         S1 := S1 + 3;
591
592      --  Otherwise we search forward for the end of the current token, marked
593      --  by a line terminator, white space, a comment symbol or if we bump
594      --  into the following token (i.e. the current token).
595
596      --  Again, it is not worth worrying about UTF_32 special line terminator
597      --  characters in this context, since this is only for error recovery.
598
599      else
600         while Source (S1) not in Line_Terminator
601           and then Source (S1) /= ' '
602           and then Source (S1) /= ASCII.HT
603           and then (Source (S1) /= '-' or else Source (S1 + 1) /= '-')
604           and then S1 /= Token_Ptr
605         loop
606            S1 := S1 + 1;
607         end loop;
608      end if;
609
610      --  S1 is now set to the location for the flag
611
612      Error_Msg (Msg, S1);
613   end Error_Msg_AP;
614
615   ------------------
616   -- Error_Msg_BC --
617   ------------------
618
619   procedure Error_Msg_BC (Msg : String) is
620   begin
621      --  If we are at end of file, post the flag after the previous token
622
623      if Token = Tok_EOF then
624         Error_Msg_AP (Msg);
625
626      --  If we are at start of file, post the flag at the current token
627
628      elsif Token_Ptr = Source_First (Current_Source_File) then
629         Error_Msg_SC (Msg);
630
631      --  If the character before the current token is a space or a horizontal
632      --  tab, then we place the flag on this character (in the case of a tab
633      --  we would really like to place it in the "last" character of the tab
634      --  space, but that it too much trouble to worry about).
635
636      elsif Source (Token_Ptr - 1) = ' '
637         or else Source (Token_Ptr - 1) = ASCII.HT
638      then
639         Error_Msg (Msg, Token_Ptr - 1);
640
641      --  If there is no space or tab before the current token, then there is
642      --  no room to place the flag before the token, so we place it on the
643      --  token instead (this happens for example at the start of a line).
644
645      else
646         Error_Msg (Msg, Token_Ptr);
647      end if;
648   end Error_Msg_BC;
649
650   -------------------
651   -- Error_Msg_CRT --
652   -------------------
653
654   procedure Error_Msg_CRT (Feature : String; N : Node_Id) is
655      CNRT : constant String := " not allowed in no run time mode";
656      CCRT : constant String := " not supported by configuration>";
657
658      S : String (1 .. Feature'Length + 1 + CCRT'Length);
659      L : Natural;
660
661   begin
662      S (1) := '|';
663      S (2 .. Feature'Length + 1) := Feature;
664      L := Feature'Length + 2;
665
666      if No_Run_Time_Mode then
667         S (L .. L + CNRT'Length - 1) := CNRT;
668         L := L + CNRT'Length - 1;
669
670      else pragma Assert (Configurable_Run_Time_Mode);
671         S (L .. L + CCRT'Length - 1) := CCRT;
672         L := L + CCRT'Length - 1;
673      end if;
674
675      Error_Msg_N (S (1 .. L), N);
676      Configurable_Run_Time_Violations := Configurable_Run_Time_Violations + 1;
677   end Error_Msg_CRT;
678
679   ------------------
680   -- Error_Msg_PT --
681   ------------------
682
683   procedure Error_Msg_PT (E : Entity_Id; Iface_Prim : Entity_Id) is
684   begin
685      Error_Msg_N
686        ("illegal overriding of subprogram inherited from interface", E);
687
688      Error_Msg_Sloc := Sloc (Iface_Prim);
689
690      if Ekind (E) = E_Function then
691         Error_Msg_N
692           ("\first formal of & declared # must be of mode `IN` "
693            & "or access-to-constant", E);
694      else
695         Error_Msg_N
696           ("\first formal of & declared # must be of mode `OUT`, `IN OUT` "
697            & "or access-to-variable", E);
698      end if;
699   end Error_Msg_PT;
700
701   -----------------
702   -- Error_Msg_F --
703   -----------------
704
705   procedure Error_Msg_F (Msg : String; N : Node_Id) is
706   begin
707      Error_Msg_NEL (Msg, N, N, Sloc (First_Node (N)));
708   end Error_Msg_F;
709
710   ------------------
711   -- Error_Msg_FE --
712   ------------------
713
714   procedure Error_Msg_FE
715     (Msg : String;
716      N   : Node_Id;
717      E   : Node_Or_Entity_Id)
718   is
719   begin
720      Error_Msg_NEL (Msg, N, E, Sloc (First_Node (N)));
721   end Error_Msg_FE;
722
723   ------------------------
724   -- Error_Msg_Internal --
725   ------------------------
726
727   procedure Error_Msg_Internal
728     (Msg      : String;
729      Sptr     : Source_Ptr;
730      Optr     : Source_Ptr;
731      Msg_Cont : Boolean)
732   is
733      Next_Msg : Error_Msg_Id;
734      --  Pointer to next message at insertion point
735
736      Prev_Msg : Error_Msg_Id;
737      --  Pointer to previous message at insertion point
738
739      Temp_Msg : Error_Msg_Id;
740
741      Warn_Err : Boolean;
742      --  Set if warning to be treated as error
743
744      procedure Handle_Serious_Error;
745      --  Internal procedure to do all error message handling for a serious
746      --  error message, other than bumping the error counts and arranging
747      --  for the message to be output.
748
749      --------------------------
750      -- Handle_Serious_Error --
751      --------------------------
752
753      procedure Handle_Serious_Error is
754      begin
755         --  Turn off code generation if not done already
756
757         if Operating_Mode = Generate_Code then
758            Operating_Mode := Check_Semantics;
759            Expander_Active := False;
760         end if;
761
762         --  Set the fatal error flag in the unit table unless we are in
763         --  Try_Semantics mode (in which case we set ignored mode if not
764         --  currently set. This stops the semantics from being performed
765         --  if we find a serious error. This is skipped if we are currently
766         --  dealing with the configuration pragma file.
767
768         if Current_Source_Unit /= No_Unit then
769            declare
770               U : constant Unit_Number_Type := Get_Source_Unit (Sptr);
771            begin
772               if Try_Semantics then
773                  if Fatal_Error (U) = None then
774                     Set_Fatal_Error (U, Error_Ignored);
775                  end if;
776               else
777                  Set_Fatal_Error (U, Error_Detected);
778               end if;
779            end;
780         end if;
781      end Handle_Serious_Error;
782
783   --  Start of processing for Error_Msg_Internal
784
785   begin
786      if Raise_Exception_On_Error /= 0 then
787         raise Error_Msg_Exception;
788      end if;
789
790      Continuation := Msg_Cont;
791      Continuation_New_Line := False;
792      Suppress_Message := False;
793      Kill_Message := False;
794      Set_Msg_Text (Msg, Sptr);
795
796      --  Kill continuation if parent message killed
797
798      if Continuation and Last_Killed then
799         return;
800      end if;
801
802      --  Return without doing anything if message is suppressed
803
804      if Suppress_Message
805        and then not All_Errors_Mode
806        and then not Is_Warning_Msg
807        and then not Is_Unconditional_Msg
808      then
809         if not Continuation then
810            Last_Killed := True;
811         end if;
812
813         return;
814      end if;
815
816      --  Return without doing anything if message is killed and this is not
817      --  the first error message. The philosophy is that if we get a weird
818      --  error message and we already have had a message, then we hope the
819      --  weird message is a junk cascaded message
820
821      if Kill_Message
822        and then not All_Errors_Mode
823        and then Total_Errors_Detected /= 0
824      then
825         if not Continuation then
826            Last_Killed := True;
827         end if;
828
829         return;
830      end if;
831
832      --  Special check for warning message to see if it should be output
833
834      if Is_Warning_Msg then
835
836         --  Immediate return if warning message and warnings are suppressed
837
838         if Warnings_Suppressed (Optr) /= No_String
839              or else
840            Warnings_Suppressed (Sptr) /= No_String
841         then
842            Cur_Msg := No_Error_Msg;
843            return;
844         end if;
845
846         --  If the flag location is in the main extended source unit then for
847         --  sure we want the warning since it definitely belongs
848
849         if In_Extended_Main_Source_Unit (Sptr) then
850            null;
851
852         --  If the main unit has not been read yet. the warning must be on
853         --  a configuration file: gnat.adc or user-defined. This means we
854         --  are not parsing the main unit yet, so skip following checks.
855
856         elsif No (Cunit (Main_Unit)) then
857            null;
858
859         --  If the flag location is not in the main extended source unit, then
860         --  we want to eliminate the warning, unless it is in the extended
861         --  main code unit and we want warnings on the instance.
862
863         elsif In_Extended_Main_Code_Unit (Sptr) and then Warn_On_Instance then
864            null;
865
866         --  Keep warning if debug flag G set
867
868         elsif Debug_Flag_GG then
869            null;
870
871         --  Keep warning if message text contains !!
872
873         elsif Has_Double_Exclam then
874            null;
875
876         --  Here is where we delete a warning from a with'ed unit
877
878         else
879            Cur_Msg := No_Error_Msg;
880
881            if not Continuation then
882               Last_Killed := True;
883            end if;
884
885            return;
886         end if;
887      end if;
888
889      --  If message is to be ignored in special ignore message mode, this is
890      --  where we do this special processing, bypassing message output.
891
892      if Ignore_Errors_Enable > 0 then
893         if Is_Serious_Error then
894            Handle_Serious_Error;
895         end if;
896
897         return;
898      end if;
899
900      --  If error message line length set, and this is a continuation message
901      --  then all we do is to append the text to the text of the last message
902      --  with a comma space separator (eliminating a possible (style) or
903      --  info prefix).
904
905      if Error_Msg_Line_Length /= 0 and then Continuation then
906         Cur_Msg := Errors.Last;
907
908         declare
909            Oldm : String_Ptr := Errors.Table (Cur_Msg).Text;
910            Newm : String (1 .. Oldm'Last + 2 + Msglen);
911            Newl : Natural;
912            M    : Natural;
913
914         begin
915            --  First copy old message to new one and free it
916
917            Newm (Oldm'Range) := Oldm.all;
918            Newl := Oldm'Length;
919            Free (Oldm);
920
921            --  Remove (style) or info: at start of message
922
923            if Msglen > 8 and then Msg_Buffer (1 .. 8) = "(style) " then
924               M := 9;
925
926            elsif Msglen > 6 and then Msg_Buffer (1 .. 6) = "info: " then
927               M := 7;
928
929            else
930               M := 1;
931            end if;
932
933            --  Now deal with separation between messages. Normally this is
934            --  simply comma space, but there are some special cases.
935
936            --  If continuation new line, then put actual NL character in msg
937
938            if Continuation_New_Line then
939               Newl := Newl + 1;
940               Newm (Newl) := ASCII.LF;
941
942            --  If continuation message is enclosed in parentheses, then
943            --  special treatment (don't need a comma, and we want to combine
944            --  successive parenthetical remarks into a single one with
945            --  separating commas).
946
947            elsif Msg_Buffer (M) = '(' and then Msg_Buffer (Msglen) = ')' then
948
949               --  Case where existing message ends in right paren, remove
950               --  and separate parenthetical remarks with a comma.
951
952               if Newm (Newl) = ')' then
953                  Newm (Newl) := ',';
954                  Msg_Buffer (M) := ' ';
955
956               --  Case where we are adding new parenthetical comment
957
958               else
959                  Newl := Newl + 1;
960                  Newm (Newl) := ' ';
961               end if;
962
963            --  Case where continuation not in parens and no new line
964
965            else
966               Newm (Newl + 1 .. Newl + 2) := ", ";
967               Newl := Newl + 2;
968            end if;
969
970            --  Append new message
971
972            Newm (Newl + 1 .. Newl + Msglen - M + 1) :=
973              Msg_Buffer (M .. Msglen);
974            Newl := Newl + Msglen - M + 1;
975            Errors.Table (Cur_Msg).Text := new String'(Newm (1 .. Newl));
976
977            --  Update warning msg flag and message doc char if needed
978
979            if Is_Warning_Msg then
980               if not Errors.Table (Cur_Msg).Warn then
981                  Errors.Table (Cur_Msg).Warn := True;
982                  Errors.Table (Cur_Msg).Warn_Chr := Warning_Msg_Char;
983
984               elsif Warning_Msg_Char /= ' ' then
985                  Errors.Table (Cur_Msg).Warn_Chr := Warning_Msg_Char;
986               end if;
987            end if;
988         end;
989
990         return;
991      end if;
992
993      --  Here we build a new error object
994
995      Errors.Append
996        ((Text     => new String'(Msg_Buffer (1 .. Msglen)),
997          Next     => No_Error_Msg,
998          Prev     => No_Error_Msg,
999          Sptr     => Sptr,
1000          Optr     => Optr,
1001          Sfile    => Get_Source_File_Index (Sptr),
1002          Line     => Get_Physical_Line_Number (Sptr),
1003          Col      => Get_Column_Number (Sptr),
1004          Warn     => Is_Warning_Msg,
1005          Info     => Is_Info_Msg,
1006          Check    => Is_Check_Msg,
1007          Warn_Err => False, -- reset below
1008          Warn_Chr => Warning_Msg_Char,
1009          Style    => Is_Style_Msg,
1010          Serious  => Is_Serious_Error,
1011          Uncond   => Is_Unconditional_Msg,
1012          Msg_Cont => Continuation,
1013          Deleted  => False));
1014      Cur_Msg := Errors.Last;
1015
1016      --  Test if warning to be treated as error
1017
1018      Warn_Err :=
1019        Is_Warning_Msg
1020          and then (Warning_Treated_As_Error (Msg_Buffer (1 .. Msglen))
1021                      or else
1022                    Warning_Treated_As_Error (Get_Warning_Tag (Cur_Msg)));
1023
1024      --  Propagate Warn_Err to this message and preceding continuations
1025
1026      for J in reverse 1 .. Errors.Last loop
1027         Errors.Table (J).Warn_Err := Warn_Err;
1028         exit when not Errors.Table (J).Msg_Cont;
1029      end loop;
1030
1031      --  If immediate errors mode set, output error message now. Also output
1032      --  now if the -d1 debug flag is set (so node number message comes out
1033      --  just before actual error message)
1034
1035      if Debug_Flag_OO or else Debug_Flag_1 then
1036         Write_Eol;
1037         Output_Source_Line
1038           (Errors.Table (Cur_Msg).Line, Errors.Table (Cur_Msg).Sfile, True);
1039         Temp_Msg := Cur_Msg;
1040         Output_Error_Msgs (Temp_Msg);
1041
1042      --  If not in immediate errors mode, then we insert the message in the
1043      --  error chain for later output by Finalize. The messages are sorted
1044      --  first by unit (main unit comes first), and within a unit by source
1045      --  location (earlier flag location first in the chain).
1046
1047      else
1048         --  First a quick check, does this belong at the very end of the chain
1049         --  of error messages. This saves a lot of time in the normal case if
1050         --  there are lots of messages.
1051
1052         if Last_Error_Msg /= No_Error_Msg
1053           and then Errors.Table (Cur_Msg).Sfile =
1054                    Errors.Table (Last_Error_Msg).Sfile
1055           and then (Sptr > Errors.Table (Last_Error_Msg).Sptr
1056                       or else
1057                          (Sptr = Errors.Table (Last_Error_Msg).Sptr
1058                             and then
1059                               Optr > Errors.Table (Last_Error_Msg).Optr))
1060         then
1061            Prev_Msg := Last_Error_Msg;
1062            Next_Msg := No_Error_Msg;
1063
1064         --  Otherwise do a full sequential search for the insertion point
1065
1066         else
1067            Prev_Msg := No_Error_Msg;
1068            Next_Msg := First_Error_Msg;
1069            while Next_Msg /= No_Error_Msg loop
1070               exit when
1071                 Errors.Table (Cur_Msg).Sfile < Errors.Table (Next_Msg).Sfile;
1072
1073               if Errors.Table (Cur_Msg).Sfile = Errors.Table (Next_Msg).Sfile
1074               then
1075                  exit when Sptr < Errors.Table (Next_Msg).Sptr
1076                    or else (Sptr = Errors.Table (Next_Msg).Sptr
1077                              and then Optr < Errors.Table (Next_Msg).Optr);
1078               end if;
1079
1080               Prev_Msg := Next_Msg;
1081               Next_Msg := Errors.Table (Next_Msg).Next;
1082            end loop;
1083         end if;
1084
1085         --  Now we insert the new message in the error chain. The insertion
1086         --  point for the message is after Prev_Msg and before Next_Msg.
1087
1088         --  The possible insertion point for the new message is after Prev_Msg
1089         --  and before Next_Msg. However, this is where we do a special check
1090         --  for redundant parsing messages, defined as messages posted on the
1091         --  same line. The idea here is that probably such messages are junk
1092         --  from the parser recovering. In full errors mode, we don't do this
1093         --  deletion, but otherwise such messages are discarded at this stage.
1094
1095         if Prev_Msg /= No_Error_Msg
1096           and then Errors.Table (Prev_Msg).Line =
1097                                             Errors.Table (Cur_Msg).Line
1098           and then Errors.Table (Prev_Msg).Sfile =
1099                                             Errors.Table (Cur_Msg).Sfile
1100           and then Compiler_State = Parsing
1101           and then not All_Errors_Mode
1102         then
1103            --  Don't delete unconditional messages and at this stage, don't
1104            --  delete continuation lines (we attempted to delete those earlier
1105            --  if the parent message was deleted.
1106
1107            if not Errors.Table (Cur_Msg).Uncond
1108              and then not Continuation
1109            then
1110               --  Don't delete if prev msg is warning and new msg is an error.
1111               --  This is because we don't want a real error masked by a
1112               --  warning. In all other cases (that is parse errors for the
1113               --  same line that are not unconditional) we do delete the
1114               --  message. This helps to avoid junk extra messages from
1115               --  cascaded parsing errors
1116
1117               if not (Errors.Table (Prev_Msg).Warn
1118                         or else
1119                       Errors.Table (Prev_Msg).Style)
1120                 or else
1121                      (Errors.Table (Cur_Msg).Warn
1122                         or else
1123                       Errors.Table (Cur_Msg).Style)
1124               then
1125                  --  All tests passed, delete the message by simply returning
1126                  --  without any further processing.
1127
1128                  if not Continuation then
1129                     Last_Killed := True;
1130                  end if;
1131
1132                  return;
1133               end if;
1134            end if;
1135         end if;
1136
1137         --  Come here if message is to be inserted in the error chain
1138
1139         if not Continuation then
1140            Last_Killed := False;
1141         end if;
1142
1143         if Prev_Msg = No_Error_Msg then
1144            First_Error_Msg := Cur_Msg;
1145         else
1146            Errors.Table (Prev_Msg).Next := Cur_Msg;
1147         end if;
1148
1149         Errors.Table (Cur_Msg).Next := Next_Msg;
1150
1151         if Next_Msg = No_Error_Msg then
1152            Last_Error_Msg := Cur_Msg;
1153         end if;
1154      end if;
1155
1156      --  Bump appropriate statistics count
1157
1158      if Errors.Table (Cur_Msg).Warn or else Errors.Table (Cur_Msg).Style then
1159         Warnings_Detected := Warnings_Detected + 1;
1160
1161         if Errors.Table (Cur_Msg).Info then
1162            Info_Messages := Info_Messages + 1;
1163         end if;
1164
1165      elsif Errors.Table (Cur_Msg).Check then
1166         Check_Messages := Check_Messages + 1;
1167
1168      else
1169         Total_Errors_Detected := Total_Errors_Detected + 1;
1170
1171         if Errors.Table (Cur_Msg).Serious then
1172            Serious_Errors_Detected := Serious_Errors_Detected + 1;
1173            Handle_Serious_Error;
1174
1175         --  If not serious error, set Fatal_Error to indicate ignored error
1176
1177         else
1178            declare
1179               U : constant Unit_Number_Type := Get_Source_Unit (Sptr);
1180            begin
1181               if Fatal_Error (U) = None then
1182                  Set_Fatal_Error (U, Error_Ignored);
1183               end if;
1184            end;
1185         end if;
1186      end if;
1187
1188      --  Record warning message issued
1189
1190      if Errors.Table (Cur_Msg).Warn
1191        and then not Errors.Table (Cur_Msg).Msg_Cont
1192      then
1193         Warning_Msg := Cur_Msg;
1194      end if;
1195
1196      --  If too many warnings turn off warnings
1197
1198      if Maximum_Messages /= 0 then
1199         if Warnings_Detected = Maximum_Messages then
1200            Warning_Mode := Suppress;
1201         end if;
1202
1203         --  If too many errors abandon compilation
1204
1205         if Total_Errors_Detected = Maximum_Messages then
1206            raise Unrecoverable_Error;
1207         end if;
1208      end if;
1209   end Error_Msg_Internal;
1210
1211   -----------------
1212   -- Error_Msg_N --
1213   -----------------
1214
1215   procedure Error_Msg_N (Msg : String; N : Node_Or_Entity_Id) is
1216   begin
1217      Error_Msg_NEL (Msg, N, N, Sloc (N));
1218   end Error_Msg_N;
1219
1220   ------------------
1221   -- Error_Msg_NE --
1222   ------------------
1223
1224   procedure Error_Msg_NE
1225     (Msg : String;
1226      N   : Node_Or_Entity_Id;
1227      E   : Node_Or_Entity_Id)
1228   is
1229   begin
1230      Error_Msg_NEL (Msg, N, E, Sloc (N));
1231   end Error_Msg_NE;
1232
1233   -------------------
1234   -- Error_Msg_NEL --
1235   -------------------
1236
1237   procedure Error_Msg_NEL
1238     (Msg           : String;
1239      N             : Node_Or_Entity_Id;
1240      E             : Node_Or_Entity_Id;
1241      Flag_Location : Source_Ptr)
1242   is
1243   begin
1244      if Special_Msg_Delete (Msg, N, E) then
1245         return;
1246      end if;
1247
1248      Prescan_Message (Msg);
1249
1250      --  Special handling for warning messages
1251
1252      if Is_Warning_Msg then
1253
1254         --  Suppress if no warnings set for either entity or node
1255
1256         if No_Warnings (N) or else No_Warnings (E) then
1257
1258            --  Disable any continuation messages as well
1259
1260            Last_Killed := True;
1261            return;
1262         end if;
1263
1264         --  Suppress if inside loop that is known to be null or is probably
1265         --  null (case where loop executes only if invalid values present).
1266         --  In either case warnings in the loop are likely to be junk.
1267
1268         declare
1269            P : Node_Id;
1270
1271         begin
1272            P := Parent (N);
1273            while Present (P) loop
1274               if Nkind (P) = N_Loop_Statement
1275                 and then Suppress_Loop_Warnings (P)
1276               then
1277                  return;
1278               end if;
1279
1280               P := Parent (P);
1281            end loop;
1282         end;
1283      end if;
1284
1285      --  Test for message to be output
1286
1287      if All_Errors_Mode
1288        or else Is_Unconditional_Msg
1289        or else Is_Warning_Msg
1290        or else OK_Node (N)
1291        or else (Msg (Msg'First) = '\' and then not Last_Killed)
1292      then
1293         Debug_Output (N);
1294         Error_Msg_Node_1 := E;
1295         Error_Msg (Msg, Flag_Location);
1296
1297      else
1298         Last_Killed := True;
1299      end if;
1300
1301      if not (Is_Warning_Msg or Is_Style_Msg) then
1302         Set_Posted (N);
1303      end if;
1304   end Error_Msg_NEL;
1305
1306   ------------------
1307   -- Error_Msg_NW --
1308   ------------------
1309
1310   procedure Error_Msg_NW
1311     (Eflag : Boolean;
1312      Msg   : String;
1313      N     : Node_Or_Entity_Id)
1314   is
1315   begin
1316      if Eflag
1317        and then In_Extended_Main_Source_Unit (N)
1318        and then Comes_From_Source (N)
1319      then
1320         Error_Msg_NEL (Msg, N, N, Sloc (N));
1321      end if;
1322   end Error_Msg_NW;
1323
1324   -----------------
1325   -- Error_Msg_S --
1326   -----------------
1327
1328   procedure Error_Msg_S (Msg : String) is
1329   begin
1330      Error_Msg (Msg, Scan_Ptr);
1331   end Error_Msg_S;
1332
1333   ------------------
1334   -- Error_Msg_SC --
1335   ------------------
1336
1337   procedure Error_Msg_SC (Msg : String) is
1338   begin
1339      --  If we are at end of file, post the flag after the previous token
1340
1341      if Token = Tok_EOF then
1342         Error_Msg_AP (Msg);
1343
1344      --  For all other cases the message is posted at the current token
1345      --  pointer position
1346
1347      else
1348         Error_Msg (Msg, Token_Ptr);
1349      end if;
1350   end Error_Msg_SC;
1351
1352   ------------------
1353   -- Error_Msg_SP --
1354   ------------------
1355
1356   procedure Error_Msg_SP (Msg : String) is
1357   begin
1358      --  Note: in the case where there is no previous token, Prev_Token_Ptr
1359      --  is set to Source_First, which is a reasonable position for the
1360      --  error flag in this situation
1361
1362      Error_Msg (Msg, Prev_Token_Ptr);
1363   end Error_Msg_SP;
1364
1365   --------------
1366   -- Finalize --
1367   --------------
1368
1369   procedure Finalize (Last_Call : Boolean) is
1370      Cur : Error_Msg_Id;
1371      Nxt : Error_Msg_Id;
1372      F   : Error_Msg_Id;
1373
1374      procedure Delete_Warning (E : Error_Msg_Id);
1375      --  Delete a warning msg if not already deleted and adjust warning count
1376
1377      --------------------
1378      -- Delete_Warning --
1379      --------------------
1380
1381      procedure Delete_Warning (E : Error_Msg_Id) is
1382      begin
1383         if not Errors.Table (E).Deleted then
1384            Errors.Table (E).Deleted := True;
1385            Warnings_Detected := Warnings_Detected - 1;
1386
1387            if Errors.Table (E).Info then
1388               Info_Messages := Info_Messages - 1;
1389            end if;
1390
1391            if Errors.Table (E).Warn_Err then
1392               Warnings_Treated_As_Errors := Warnings_Treated_As_Errors - 1;
1393            end if;
1394         end if;
1395      end Delete_Warning;
1396
1397   --  Start of processing for Finalize
1398
1399   begin
1400      --  Set Prev pointers
1401
1402      Cur := First_Error_Msg;
1403      while Cur /= No_Error_Msg loop
1404         Nxt := Errors.Table (Cur).Next;
1405         exit when Nxt = No_Error_Msg;
1406         Errors.Table (Nxt).Prev := Cur;
1407         Cur := Nxt;
1408      end loop;
1409
1410      --  Eliminate any duplicated error messages from the list. This is
1411      --  done after the fact to avoid problems with Change_Error_Text.
1412
1413      Cur := First_Error_Msg;
1414      while Cur /= No_Error_Msg loop
1415         Nxt := Errors.Table (Cur).Next;
1416
1417         F := Nxt;
1418         while F /= No_Error_Msg
1419           and then Errors.Table (F).Sptr = Errors.Table (Cur).Sptr
1420         loop
1421            Check_Duplicate_Message (Cur, F);
1422            F := Errors.Table (F).Next;
1423         end loop;
1424
1425         Cur := Nxt;
1426      end loop;
1427
1428      --  Mark any messages suppressed by specific warnings as Deleted
1429
1430      Cur := First_Error_Msg;
1431      while Cur /= No_Error_Msg loop
1432         declare
1433            CE  : Error_Msg_Object renames Errors.Table (Cur);
1434            Tag : constant String := Get_Warning_Tag (Cur);
1435
1436         begin
1437            if (CE.Warn and not CE.Deleted)
1438              and then
1439                   (Warning_Specifically_Suppressed (CE.Sptr, CE.Text, Tag) /=
1440                                                                   No_String
1441                      or else
1442                    Warning_Specifically_Suppressed (CE.Optr, CE.Text, Tag) /=
1443                                                                   No_String)
1444            then
1445               Delete_Warning (Cur);
1446
1447               --  If this is a continuation, delete previous parts of message
1448
1449               F := Cur;
1450               while Errors.Table (F).Msg_Cont loop
1451                  F := Errors.Table (F).Prev;
1452                  exit when F = No_Error_Msg;
1453                  Delete_Warning (F);
1454               end loop;
1455
1456               --  Delete any following continuations
1457
1458               F := Cur;
1459               loop
1460                  F := Errors.Table (F).Next;
1461                  exit when F = No_Error_Msg;
1462                  exit when not Errors.Table (F).Msg_Cont;
1463                  Delete_Warning (F);
1464               end loop;
1465            end if;
1466         end;
1467
1468         Cur := Errors.Table (Cur).Next;
1469      end loop;
1470
1471      Finalize_Called := True;
1472
1473      --  Check consistency of specific warnings (may add warnings). We only
1474      --  do this on the last call, after all possible warnings are posted.
1475
1476      if Last_Call then
1477         Validate_Specific_Warnings (Error_Msg'Access);
1478      end if;
1479   end Finalize;
1480
1481   ----------------
1482   -- First_Node --
1483   ----------------
1484
1485   function First_Node (C : Node_Id) return Node_Id is
1486      Orig     : constant Node_Id           := Original_Node (C);
1487      Loc      : constant Source_Ptr        := Sloc (Orig);
1488      Sfile    : constant Source_File_Index := Get_Source_File_Index (Loc);
1489      Earliest : Node_Id;
1490      Eloc     : Source_Ptr;
1491
1492      function Test_Earlier (N : Node_Id) return Traverse_Result;
1493      --  Function applied to every node in the construct
1494
1495      procedure Search_Tree_First is new Traverse_Proc (Test_Earlier);
1496      --  Create traversal procedure
1497
1498      ------------------
1499      -- Test_Earlier --
1500      ------------------
1501
1502      function Test_Earlier (N : Node_Id) return Traverse_Result is
1503         Norig : constant Node_Id    := Original_Node (N);
1504         Loc   : constant Source_Ptr := Sloc (Norig);
1505
1506      begin
1507         --  Check for earlier
1508
1509         if Loc < Eloc
1510
1511           --  Ignore nodes with no useful location information
1512
1513           and then Loc /= Standard_Location
1514           and then Loc /= No_Location
1515
1516           --  Ignore nodes from a different file. This ensures against cases
1517           --  of strange foreign code somehow being present. We don't want
1518           --  wild placement of messages if that happens.
1519
1520           and then Get_Source_File_Index (Loc) = Sfile
1521         then
1522            Earliest := Norig;
1523            Eloc     := Loc;
1524         end if;
1525
1526         return OK_Orig;
1527      end Test_Earlier;
1528
1529   --  Start of processing for First_Node
1530
1531   begin
1532      if Nkind (Orig) in N_Subexpr then
1533         Earliest := Orig;
1534         Eloc := Loc;
1535         Search_Tree_First (Orig);
1536         return Earliest;
1537
1538      else
1539         return Orig;
1540      end if;
1541   end First_Node;
1542
1543   ----------------
1544   -- First_Sloc --
1545   ----------------
1546
1547   function First_Sloc (N : Node_Id) return Source_Ptr is
1548      SI : constant Source_File_Index := Source_Index (Get_Source_Unit (N));
1549      SF : constant Source_Ptr        := Source_First (SI);
1550      F  : Node_Id;
1551      S  : Source_Ptr;
1552
1553   begin
1554      F := First_Node (N);
1555      S := Sloc (F);
1556
1557      --  The following circuit is a bit subtle. When we have parenthesized
1558      --  expressions, then the Sloc will not record the location of the paren,
1559      --  but we would like to post the flag on the paren. So what we do is to
1560      --  crawl up the tree from the First_Node, adjusting the Sloc value for
1561      --  any parentheses we know are present. Yes, we know this circuit is not
1562      --  100% reliable (e.g. because we don't record all possible paren level
1563      --  values), but this is only for an error message so it is good enough.
1564
1565      Node_Loop : loop
1566         Paren_Loop : for J in 1 .. Paren_Count (F) loop
1567
1568            --  We don't look more than 12 characters behind the current
1569            --  location, and in any case not past the front of the source.
1570
1571            Search_Loop : for K in 1 .. 12 loop
1572               exit Search_Loop when S = SF;
1573
1574               if Source_Text (SI) (S - 1) = '(' then
1575                  S := S - 1;
1576                  exit Search_Loop;
1577
1578               elsif Source_Text (SI) (S - 1) <= ' ' then
1579                  S := S - 1;
1580
1581               else
1582                  exit Search_Loop;
1583               end if;
1584            end loop Search_Loop;
1585         end loop Paren_Loop;
1586
1587         exit Node_Loop when F = N;
1588         F := Parent (F);
1589         exit Node_Loop when Nkind (F) not in N_Subexpr;
1590      end loop Node_Loop;
1591
1592      return S;
1593   end First_Sloc;
1594
1595   -----------------------
1596   -- Get_Ignore_Errors --
1597   -----------------------
1598
1599   function Get_Ignore_Errors return Boolean is
1600   begin
1601      return Errors_Must_Be_Ignored;
1602   end Get_Ignore_Errors;
1603
1604   ----------------
1605   -- Initialize --
1606   ----------------
1607
1608   procedure Initialize is
1609   begin
1610      Errors.Init;
1611      First_Error_Msg := No_Error_Msg;
1612      Last_Error_Msg := No_Error_Msg;
1613      Serious_Errors_Detected := 0;
1614      Total_Errors_Detected := 0;
1615      Warnings_Treated_As_Errors := 0;
1616      Warnings_Detected := 0;
1617      Info_Messages := 0;
1618      Warnings_As_Errors_Count := 0;
1619      Cur_Msg := No_Error_Msg;
1620      List_Pragmas.Init;
1621
1622      --  Initialize warnings tables
1623
1624      Warnings.Init;
1625      Specific_Warnings.Init;
1626   end Initialize;
1627
1628   -----------------
1629   -- No_Warnings --
1630   -----------------
1631
1632   function No_Warnings (N : Node_Or_Entity_Id) return Boolean is
1633   begin
1634      if Error_Posted (N) then
1635         return True;
1636
1637      elsif Nkind (N) in N_Entity and then Has_Warnings_Off (N) then
1638         return True;
1639
1640      elsif Is_Entity_Name (N)
1641        and then Present (Entity (N))
1642        and then Has_Warnings_Off (Entity (N))
1643      then
1644         return True;
1645
1646      else
1647         return False;
1648      end if;
1649   end No_Warnings;
1650
1651   -------------
1652   -- OK_Node --
1653   -------------
1654
1655   function OK_Node (N : Node_Id) return Boolean is
1656      K : constant Node_Kind := Nkind (N);
1657
1658   begin
1659      if Error_Posted (N) then
1660         return False;
1661
1662      elsif K in N_Has_Etype
1663        and then Present (Etype (N))
1664        and then Error_Posted (Etype (N))
1665      then
1666         return False;
1667
1668      elsif (K in N_Op
1669              or else K = N_Attribute_Reference
1670              or else K = N_Character_Literal
1671              or else K = N_Expanded_Name
1672              or else K = N_Identifier
1673              or else K = N_Operator_Symbol)
1674        and then Present (Entity (N))
1675        and then Error_Posted (Entity (N))
1676      then
1677         return False;
1678      else
1679         return True;
1680      end if;
1681   end OK_Node;
1682
1683   ---------------------
1684   -- Output_Messages --
1685   ---------------------
1686
1687   procedure Output_Messages is
1688      E        : Error_Msg_Id;
1689      Err_Flag : Boolean;
1690
1691      procedure Write_Error_Summary;
1692      --  Write error summary
1693
1694      procedure Write_Header (Sfile : Source_File_Index);
1695      --  Write header line (compiling or checking given file)
1696
1697      procedure Write_Max_Errors;
1698      --  Write message if max errors reached
1699
1700      -------------------------
1701      -- Write_Error_Summary --
1702      -------------------------
1703
1704      procedure Write_Error_Summary is
1705      begin
1706         --  Extra blank line if error messages or source listing were output
1707
1708         if Total_Errors_Detected + Warnings_Detected > 0 or else Full_List
1709         then
1710            Write_Eol;
1711         end if;
1712
1713         --  Message giving number of lines read and number of errors detected.
1714         --  This normally goes to Standard_Output. The exception is when brief
1715         --  mode is not set, verbose mode (or full list mode) is set, and
1716         --  there are errors. In this case we send the message to standard
1717         --  error to make sure that *something* appears on standard error
1718         --  in an error situation.
1719
1720         if Total_Errors_Detected + Warnings_Detected /= 0
1721           and then not Brief_Output
1722           and then (Verbose_Mode or Full_List)
1723         then
1724            Set_Standard_Error;
1725         end if;
1726
1727         --  Message giving total number of lines. Don't give this message if
1728         --  the Main_Source line is unknown (this happens in error situations,
1729         --  e.g. when integrated preprocessing fails).
1730
1731         if Main_Source_File /= No_Source_File then
1732            Write_Str (" ");
1733            Write_Int (Num_Source_Lines (Main_Source_File));
1734
1735            if Num_Source_Lines (Main_Source_File) = 1 then
1736               Write_Str (" line: ");
1737            else
1738               Write_Str (" lines: ");
1739            end if;
1740         end if;
1741
1742         if Total_Errors_Detected = 0 then
1743            Write_Str ("No errors");
1744
1745         elsif Total_Errors_Detected = 1 then
1746            Write_Str ("1 error");
1747
1748         else
1749            Write_Int (Total_Errors_Detected);
1750            Write_Str (" errors");
1751         end if;
1752
1753         if Warnings_Detected - Info_Messages /= 0 then
1754            Write_Str (", ");
1755            Write_Int (Warnings_Detected);
1756            Write_Str (" warning");
1757
1758            if Warnings_Detected - Info_Messages /= 1 then
1759               Write_Char ('s');
1760            end if;
1761
1762            if Warning_Mode = Treat_As_Error then
1763               Write_Str (" (treated as error");
1764
1765               if Warnings_Detected /= 1 then
1766                  Write_Char ('s');
1767               end if;
1768
1769               Write_Char (')');
1770
1771            elsif Warnings_Treated_As_Errors /= 0 then
1772               Write_Str (" (");
1773               Write_Int (Warnings_Treated_As_Errors);
1774               Write_Str (" treated as errors)");
1775            end if;
1776         end if;
1777
1778         if Info_Messages /= 0 then
1779            Write_Str (", ");
1780            Write_Int (Info_Messages);
1781            Write_Str (" info message");
1782
1783            if Info_Messages > 1 then
1784               Write_Char ('s');
1785            end if;
1786         end if;
1787
1788         Write_Eol;
1789         Set_Standard_Output;
1790      end Write_Error_Summary;
1791
1792      ------------------
1793      -- Write_Header --
1794      ------------------
1795
1796      procedure Write_Header (Sfile : Source_File_Index) is
1797      begin
1798         if Verbose_Mode or Full_List then
1799            if Original_Operating_Mode = Generate_Code then
1800               Write_Str ("Compiling: ");
1801            else
1802               Write_Str ("Checking: ");
1803            end if;
1804
1805            Write_Name (Full_File_Name (Sfile));
1806
1807            if not Debug_Flag_7 then
1808               Write_Eol;
1809               Write_Str ("Source file time stamp: ");
1810               Write_Time_Stamp (Sfile);
1811               Write_Eol;
1812               Write_Str ("Compiled at: " & Compilation_Time);
1813            end if;
1814
1815            Write_Eol;
1816         end if;
1817      end Write_Header;
1818
1819      ----------------------
1820      -- Write_Max_Errors --
1821      ----------------------
1822
1823      procedure Write_Max_Errors is
1824      begin
1825         if Maximum_Messages /= 0 then
1826            if Warnings_Detected >= Maximum_Messages then
1827               Set_Standard_Error;
1828               Write_Line ("maximum number of warnings output");
1829               Write_Line ("any further warnings suppressed");
1830               Set_Standard_Output;
1831            end if;
1832
1833            --  If too many errors print message
1834
1835            if Total_Errors_Detected >= Maximum_Messages then
1836               Set_Standard_Error;
1837               Write_Line ("fatal error: maximum number of errors detected");
1838               Set_Standard_Output;
1839            end if;
1840         end if;
1841      end Write_Max_Errors;
1842
1843   --  Start of processing for Output_Messages
1844
1845   begin
1846      --  Error if Finalize has not been called
1847
1848      if not Finalize_Called then
1849         raise Program_Error;
1850      end if;
1851
1852      --  Reset current error source file if the main unit has a pragma
1853      --  Source_Reference. This ensures outputting the proper name of
1854      --  the source file in this situation.
1855
1856      if Main_Source_File = No_Source_File
1857        or else Num_SRef_Pragmas (Main_Source_File) /= 0
1858      then
1859         Current_Error_Source_File := No_Source_File;
1860      end if;
1861
1862      --  Brief Error mode
1863
1864      if Brief_Output or (not Full_List and not Verbose_Mode) then
1865         Set_Standard_Error;
1866
1867         E := First_Error_Msg;
1868         while E /= No_Error_Msg loop
1869            if not Errors.Table (E).Deleted and then not Debug_Flag_KK then
1870               if Full_Path_Name_For_Brief_Errors then
1871                  Write_Name (Full_Ref_Name (Errors.Table (E).Sfile));
1872               else
1873                  Write_Name (Reference_Name (Errors.Table (E).Sfile));
1874               end if;
1875
1876               Write_Char (':');
1877               Write_Int (Int (Physical_To_Logical
1878                                (Errors.Table (E).Line,
1879                                 Errors.Table (E).Sfile)));
1880               Write_Char (':');
1881
1882               if Errors.Table (E).Col < 10 then
1883                  Write_Char ('0');
1884               end if;
1885
1886               Write_Int (Int (Errors.Table (E).Col));
1887               Write_Str (": ");
1888               Output_Msg_Text (E);
1889               Write_Eol;
1890            end if;
1891
1892            E := Errors.Table (E).Next;
1893         end loop;
1894
1895         Set_Standard_Output;
1896      end if;
1897
1898      --  Full source listing case
1899
1900      if Full_List then
1901         List_Pragmas_Index := 1;
1902         List_Pragmas_Mode := True;
1903         E := First_Error_Msg;
1904
1905         --  Normal case, to stdout (copyright notice already output)
1906
1907         if Full_List_File_Name = null then
1908            if not Debug_Flag_7 then
1909               Write_Eol;
1910            end if;
1911
1912         --  Output to file
1913
1914         else
1915            Create_List_File_Access.all (Full_List_File_Name.all);
1916            Set_Special_Output (Write_List_Info_Access.all'Access);
1917
1918            --  Write copyright notice to file
1919
1920            if not Debug_Flag_7 then
1921               Write_Str ("GNAT ");
1922               Write_Str (Gnat_Version_String);
1923               Write_Eol;
1924               Write_Str ("Copyright 1992-" &
1925                          Current_Year &
1926                          ", Free Software Foundation, Inc.");
1927               Write_Eol;
1928            end if;
1929         end if;
1930
1931         --  First list extended main source file units with errors
1932
1933         for U in Main_Unit .. Last_Unit loop
1934            if In_Extended_Main_Source_Unit (Cunit_Entity (U))
1935
1936              --  If debug flag d.m is set, only the main source is listed
1937
1938              and then (U = Main_Unit or else not Debug_Flag_Dot_M)
1939
1940              --  If the unit of the entity does not come from source, it is
1941              --  an implicit subprogram declaration for a child subprogram.
1942              --  Do not emit errors for it, they are listed with the body.
1943
1944              and then
1945                (No (Cunit_Entity (U))
1946                  or else Comes_From_Source (Cunit_Entity (U))
1947                  or else not Is_Subprogram (Cunit_Entity (U)))
1948
1949              --  If the compilation unit associated with this unit does not
1950              --  come from source, it means it is an instantiation that should
1951              --  not be included in the source listing.
1952
1953              and then Comes_From_Source (Cunit (U))
1954            then
1955               declare
1956                  Sfile : constant Source_File_Index := Source_Index (U);
1957
1958               begin
1959                  Write_Eol;
1960
1961                  --  Only write the header if Sfile is known
1962
1963                  if Sfile /= No_Source_File then
1964                     Write_Header (Sfile);
1965                     Write_Eol;
1966                  end if;
1967
1968                  --  Normally, we don't want an "error messages from file"
1969                  --  message when listing the entire file, so we set the
1970                  --  current source file as the current error source file.
1971                  --  However, the old style of doing things was to list this
1972                  --  message if pragma Source_Reference is present, even for
1973                  --  the main unit. Since the purpose of the -gnatd.m switch
1974                  --  is to duplicate the old behavior, we skip the reset if
1975                  --  this debug flag is set.
1976
1977                  if not Debug_Flag_Dot_M then
1978                     Current_Error_Source_File := Sfile;
1979                  end if;
1980
1981                  --  Only output the listing if Sfile is known, to avoid
1982                  --  crashing the compiler.
1983
1984                  if Sfile /= No_Source_File then
1985                     for N in 1 .. Last_Source_Line (Sfile) loop
1986                        while E /= No_Error_Msg
1987                          and then Errors.Table (E).Deleted
1988                        loop
1989                           E := Errors.Table (E).Next;
1990                        end loop;
1991
1992                        Err_Flag :=
1993                          E /= No_Error_Msg
1994                            and then Errors.Table (E).Line = N
1995                            and then Errors.Table (E).Sfile = Sfile;
1996
1997                        Output_Source_Line (N, Sfile, Err_Flag);
1998
1999                        if Err_Flag then
2000                           Output_Error_Msgs (E);
2001
2002                           if not Debug_Flag_2 then
2003                              Write_Eol;
2004                           end if;
2005                        end if;
2006                     end loop;
2007                  end if;
2008               end;
2009            end if;
2010         end loop;
2011
2012         --  Then output errors, if any, for subsidiary units not in the
2013         --  main extended unit.
2014
2015         --  Note: if debug flag d.m set, include errors for any units other
2016         --  than the main unit in the extended source unit (e.g. spec and
2017         --  subunits for a body).
2018
2019         while E /= No_Error_Msg
2020           and then (not In_Extended_Main_Source_Unit (Errors.Table (E).Sptr)
2021                       or else
2022                        (Debug_Flag_Dot_M
2023                          and then Get_Source_Unit
2024                                     (Errors.Table (E).Sptr) /= Main_Unit))
2025         loop
2026            if Errors.Table (E).Deleted then
2027               E := Errors.Table (E).Next;
2028
2029            else
2030               Write_Eol;
2031               Output_Source_Line
2032                 (Errors.Table (E).Line, Errors.Table (E).Sfile, True);
2033               Output_Error_Msgs (E);
2034            end if;
2035         end loop;
2036
2037         --  If output to file, write extra copy of error summary to the
2038         --  output file, and then close it.
2039
2040         if Full_List_File_Name /= null then
2041            Write_Error_Summary;
2042            Write_Max_Errors;
2043            Close_List_File_Access.all;
2044            Cancel_Special_Output;
2045         end if;
2046      end if;
2047
2048      --  Verbose mode (error lines only with error flags). Normally this is
2049      --  ignored in full list mode, unless we are listing to a file, in which
2050      --  case we still generate -gnatv output to standard output.
2051
2052      if Verbose_Mode
2053        and then (not Full_List or else Full_List_File_Name /= null)
2054      then
2055         Write_Eol;
2056
2057         --  Output the header only when Main_Source_File is known
2058
2059         if Main_Source_File /= No_Source_File then
2060            Write_Header (Main_Source_File);
2061         end if;
2062
2063         E := First_Error_Msg;
2064
2065         --  Loop through error lines
2066
2067         while E /= No_Error_Msg loop
2068            if Errors.Table (E).Deleted then
2069               E := Errors.Table (E).Next;
2070            else
2071               Write_Eol;
2072               Output_Source_Line
2073                 (Errors.Table (E).Line, Errors.Table (E).Sfile, True);
2074               Output_Error_Msgs (E);
2075            end if;
2076         end loop;
2077      end if;
2078
2079      --  Output error summary if verbose or full list mode
2080
2081      if Verbose_Mode or else Full_List then
2082         Write_Error_Summary;
2083      end if;
2084
2085      Write_Max_Errors;
2086
2087      if Warning_Mode = Treat_As_Error then
2088         Total_Errors_Detected :=
2089           Total_Errors_Detected + Warnings_Detected - Info_Messages;
2090         Warnings_Detected := Info_Messages;
2091      end if;
2092   end Output_Messages;
2093
2094   ------------------------
2095   -- Output_Source_Line --
2096   ------------------------
2097
2098   procedure Output_Source_Line
2099     (L     : Physical_Line_Number;
2100      Sfile : Source_File_Index;
2101      Errs  : Boolean)
2102   is
2103      S : Source_Ptr;
2104      C : Character;
2105
2106      Line_Number_Output : Boolean := False;
2107      --  Set True once line number is output
2108
2109      Empty_Line : Boolean := True;
2110      --  Set False if line includes at least one character
2111
2112   begin
2113      if Sfile /= Current_Error_Source_File then
2114         Write_Str ("==============Error messages for ");
2115
2116         case Sinput.File_Type (Sfile) is
2117            when Sinput.Src =>
2118               Write_Str ("source");
2119
2120            when Sinput.Config =>
2121               Write_Str ("configuration pragmas");
2122
2123            when Sinput.Def =>
2124               Write_Str ("symbol definition");
2125
2126            when Sinput.Preproc =>
2127               Write_Str ("preprocessing data");
2128         end case;
2129
2130         Write_Str (" file: ");
2131         Write_Name (Full_File_Name (Sfile));
2132         Write_Eol;
2133
2134         if Num_SRef_Pragmas (Sfile) > 0 then
2135            Write_Str ("--------------Line numbers from file: ");
2136            Write_Name (Full_Ref_Name (Sfile));
2137            Write_Str (" (starting at line ");
2138            Write_Int (Int (First_Mapped_Line (Sfile)));
2139            Write_Char (')');
2140            Write_Eol;
2141         end if;
2142
2143         Current_Error_Source_File := Sfile;
2144      end if;
2145
2146      if Errs or List_Pragmas_Mode then
2147         Output_Line_Number (Physical_To_Logical (L, Sfile));
2148         Line_Number_Output := True;
2149      end if;
2150
2151      S := Line_Start (L, Sfile);
2152
2153      loop
2154         C := Source_Text (Sfile) (S);
2155         exit when C = ASCII.LF or else C = ASCII.CR or else C = EOF;
2156
2157         --  Deal with matching entry in List_Pragmas table
2158
2159         if Full_List
2160           and then List_Pragmas_Index <= List_Pragmas.Last
2161           and then S = List_Pragmas.Table (List_Pragmas_Index).Ploc
2162         then
2163            case List_Pragmas.Table (List_Pragmas_Index).Ptyp is
2164               when Page =>
2165                  Write_Char (C);
2166
2167                  --  Ignore if on line with errors so that error flags
2168                  --  get properly listed with the error line .
2169
2170                  if not Errs then
2171                     Write_Char (ASCII.FF);
2172                  end if;
2173
2174               when List_On =>
2175                  List_Pragmas_Mode := True;
2176
2177                  if not Line_Number_Output then
2178                     Output_Line_Number (Physical_To_Logical (L, Sfile));
2179                     Line_Number_Output := True;
2180                  end if;
2181
2182                  Write_Char (C);
2183
2184               when List_Off =>
2185                  Write_Char (C);
2186                  List_Pragmas_Mode := False;
2187            end case;
2188
2189            List_Pragmas_Index := List_Pragmas_Index + 1;
2190
2191         --  Normal case (no matching entry in List_Pragmas table)
2192
2193         else
2194            if Errs or List_Pragmas_Mode then
2195               Write_Char (C);
2196            end if;
2197         end if;
2198
2199         Empty_Line := False;
2200         S := S + 1;
2201      end loop;
2202
2203      --  If we have output a source line, then add the line terminator, with
2204      --  training spaces preserved (so we output the line exactly as input).
2205
2206      if Line_Number_Output then
2207         if Empty_Line then
2208            Write_Eol;
2209         else
2210            Write_Eol_Keep_Blanks;
2211         end if;
2212      end if;
2213   end Output_Source_Line;
2214
2215   -----------------------------
2216   -- Remove_Warning_Messages --
2217   -----------------------------
2218
2219   procedure Remove_Warning_Messages (N : Node_Id) is
2220
2221      function Check_For_Warning (N : Node_Id) return Traverse_Result;
2222      --  This function checks one node for a possible warning message
2223
2224      function Check_All_Warnings is new Traverse_Func (Check_For_Warning);
2225      --  This defines the traversal operation
2226
2227      -----------------------
2228      -- Check_For_Warning --
2229      -----------------------
2230
2231      function Check_For_Warning (N : Node_Id) return Traverse_Result is
2232         Loc : constant Source_Ptr := Sloc (N);
2233         E   : Error_Msg_Id;
2234
2235         function To_Be_Removed (E : Error_Msg_Id) return Boolean;
2236         --  Returns True for a message that is to be removed. Also adjusts
2237         --  warning count appropriately.
2238
2239         -------------------
2240         -- To_Be_Removed --
2241         -------------------
2242
2243         function To_Be_Removed (E : Error_Msg_Id) return Boolean is
2244         begin
2245            if E /= No_Error_Msg
2246
2247               --  Don't remove if location does not match
2248
2249               and then Errors.Table (E).Optr = Loc
2250
2251               --  Don't remove if not warning/info message. Note that we do
2252               --  not remove style messages here. They are warning messages
2253               --  but not ones we want removed in this context.
2254
2255               and then Errors.Table (E).Warn
2256
2257               --  Don't remove unconditional messages
2258
2259               and then not Errors.Table (E).Uncond
2260            then
2261               Warnings_Detected := Warnings_Detected - 1;
2262
2263               if Errors.Table (E).Info then
2264                  Info_Messages := Info_Messages - 1;
2265               end if;
2266
2267               return True;
2268
2269            --  No removal required
2270
2271            else
2272               return False;
2273            end if;
2274         end To_Be_Removed;
2275
2276      --  Start of processing for Check_For_Warnings
2277
2278      begin
2279         while To_Be_Removed (First_Error_Msg) loop
2280            First_Error_Msg := Errors.Table (First_Error_Msg).Next;
2281         end loop;
2282
2283         if First_Error_Msg = No_Error_Msg then
2284            Last_Error_Msg := No_Error_Msg;
2285         end if;
2286
2287         E := First_Error_Msg;
2288         while E /= No_Error_Msg loop
2289            while To_Be_Removed (Errors.Table (E).Next) loop
2290               Errors.Table (E).Next :=
2291                 Errors.Table (Errors.Table (E).Next).Next;
2292
2293               if Errors.Table (E).Next = No_Error_Msg then
2294                  Last_Error_Msg := E;
2295               end if;
2296            end loop;
2297
2298            E := Errors.Table (E).Next;
2299         end loop;
2300
2301         if Nkind (N) = N_Raise_Constraint_Error
2302           and then Original_Node (N) /= N
2303           and then No (Condition (N))
2304         then
2305            --  Warnings may have been posted on subexpressions of the original
2306            --  tree. We place the original node back on the tree to remove
2307            --  those warnings, whose sloc do not match those of any node in
2308            --  the current tree. Given that we are in unreachable code, this
2309            --  modification to the tree is harmless.
2310
2311            declare
2312               Status : Traverse_Final_Result;
2313
2314            begin
2315               if Is_List_Member (N) then
2316                  Set_Condition (N, Original_Node (N));
2317                  Status := Check_All_Warnings (Condition (N));
2318               else
2319                  Rewrite (N, Original_Node (N));
2320                  Status := Check_All_Warnings (N);
2321               end if;
2322
2323               return Status;
2324            end;
2325
2326         else
2327            return OK;
2328         end if;
2329      end Check_For_Warning;
2330
2331   --  Start of processing for Remove_Warning_Messages
2332
2333   begin
2334      if Warnings_Detected /= 0 then
2335         declare
2336            Discard : Traverse_Final_Result;
2337            pragma Warnings (Off, Discard);
2338
2339         begin
2340            Discard := Check_All_Warnings (N);
2341         end;
2342      end if;
2343   end Remove_Warning_Messages;
2344
2345   procedure Remove_Warning_Messages (L : List_Id) is
2346      Stat : Node_Id;
2347   begin
2348      if Is_Non_Empty_List (L) then
2349         Stat := First (L);
2350         while Present (Stat) loop
2351            Remove_Warning_Messages (Stat);
2352            Next (Stat);
2353         end loop;
2354      end if;
2355   end Remove_Warning_Messages;
2356
2357   ----------------------
2358   -- Adjust_Name_Case --
2359   ----------------------
2360
2361   procedure Adjust_Name_Case (Loc : Source_Ptr) is
2362   begin
2363      --  We have an all lower case name from Namet, and now we want to set
2364      --  the appropriate case. If possible we copy the actual casing from
2365      --  the source. If not we use standard identifier casing.
2366
2367      declare
2368         Src_Ind : constant Source_File_Index := Get_Source_File_Index (Loc);
2369         Sbuffer : Source_Buffer_Ptr;
2370         Ref_Ptr : Integer;
2371         Src_Ptr : Source_Ptr;
2372
2373      begin
2374         Ref_Ptr := 1;
2375         Src_Ptr := Loc;
2376
2377         --  For standard locations, always use mixed case
2378
2379         if Loc <= No_Location then
2380            Set_Casing (Mixed_Case);
2381
2382         else
2383            --  Determine if the reference we are dealing with corresponds to
2384            --  text at the point of the error reference. This will often be
2385            --  the case for simple identifier references, and is the case
2386            --  where we can copy the casing from the source.
2387
2388            Sbuffer := Source_Text (Src_Ind);
2389
2390            while Ref_Ptr <= Name_Len loop
2391               exit when
2392                 Fold_Lower (Sbuffer (Src_Ptr)) /=
2393                   Fold_Lower (Name_Buffer (Ref_Ptr));
2394               Ref_Ptr := Ref_Ptr + 1;
2395               Src_Ptr := Src_Ptr + 1;
2396            end loop;
2397
2398            --  If we get through the loop without a mismatch, then output the
2399            --  name the way it is cased in the source program
2400
2401            if Ref_Ptr > Name_Len then
2402               Src_Ptr := Loc;
2403
2404               for J in 1 .. Name_Len loop
2405                  Name_Buffer (J) := Sbuffer (Src_Ptr);
2406                  Src_Ptr := Src_Ptr + 1;
2407               end loop;
2408
2409            --  Otherwise set the casing using the default identifier casing
2410
2411            else
2412               Set_Casing (Identifier_Casing (Src_Ind), Mixed_Case);
2413            end if;
2414         end if;
2415      end;
2416   end Adjust_Name_Case;
2417
2418   ---------------------------
2419   -- Set_Identifier_Casing --
2420   ---------------------------
2421
2422   procedure Set_Identifier_Casing
2423     (Identifier_Name : System.Address;
2424      File_Name       : System.Address)
2425   is
2426      Ident : constant Big_String_Ptr := To_Big_String_Ptr (Identifier_Name);
2427      File  : constant Big_String_Ptr := To_Big_String_Ptr (File_Name);
2428      Flen  : Natural;
2429
2430      Desired_Case : Casing_Type := Mixed_Case;
2431      --  Casing required for result. Default value of Mixed_Case is used if
2432      --  for some reason we cannot find the right file name in the table.
2433
2434   begin
2435      --  Get length of file name
2436
2437      Flen := 0;
2438      while File (Flen + 1) /= ASCII.NUL loop
2439         Flen := Flen + 1;
2440      end loop;
2441
2442      --  Loop through file names to find matching one. This is a bit slow, but
2443      --  we only do it in error situations so it is not so terrible. Note that
2444      --  if the loop does not exit, then the desired case will be left set to
2445      --  Mixed_Case, this can happen if the name was not in canonical form.
2446
2447      for J in 1 .. Last_Source_File loop
2448         Get_Name_String (Full_Debug_Name (J));
2449
2450         if Name_Len = Flen
2451           and then Name_Buffer (1 .. Name_Len) = String (File (1 .. Flen))
2452         then
2453            Desired_Case := Identifier_Casing (J);
2454            exit;
2455         end if;
2456      end loop;
2457
2458      --  Copy identifier as given to Name_Buffer
2459
2460      for J in Name_Buffer'Range loop
2461         Name_Buffer (J) := Ident (J);
2462
2463         if Name_Buffer (J) = ASCII.NUL then
2464            Name_Len := J - 1;
2465            exit;
2466         end if;
2467      end loop;
2468
2469      Set_Casing (Desired_Case);
2470   end Set_Identifier_Casing;
2471
2472   -----------------------
2473   -- Set_Ignore_Errors --
2474   -----------------------
2475
2476   procedure Set_Ignore_Errors (To : Boolean) is
2477   begin
2478      Errors_Must_Be_Ignored := To;
2479   end Set_Ignore_Errors;
2480
2481   ------------------------------
2482   -- Set_Msg_Insertion_Column --
2483   ------------------------------
2484
2485   procedure Set_Msg_Insertion_Column is
2486   begin
2487      if RM_Column_Check then
2488         Set_Msg_Str (" in column ");
2489         Set_Msg_Int (Int (Error_Msg_Col) + 1);
2490      end if;
2491   end Set_Msg_Insertion_Column;
2492
2493   ----------------------------
2494   -- Set_Msg_Insertion_Node --
2495   ----------------------------
2496
2497   procedure Set_Msg_Insertion_Node is
2498      K : Node_Kind;
2499
2500   begin
2501      Suppress_Message :=
2502        Error_Msg_Node_1 = Error
2503          or else Error_Msg_Node_1 = Any_Type;
2504
2505      if Error_Msg_Node_1 = Empty then
2506         Set_Msg_Blank_Conditional;
2507         Set_Msg_Str ("<empty>");
2508
2509      elsif Error_Msg_Node_1 = Error then
2510         Set_Msg_Blank;
2511         Set_Msg_Str ("<error>");
2512
2513      elsif Error_Msg_Node_1 = Standard_Void_Type then
2514         Set_Msg_Blank;
2515         Set_Msg_Str ("procedure name");
2516
2517      elsif Nkind (Error_Msg_Node_1) in N_Entity
2518        and then Ekind (Error_Msg_Node_1) = E_Anonymous_Access_Subprogram_Type
2519      then
2520         Set_Msg_Blank;
2521         Set_Msg_Str ("access to subprogram");
2522
2523      else
2524         Set_Msg_Blank_Conditional;
2525
2526         --  Output name
2527
2528         K := Nkind (Error_Msg_Node_1);
2529
2530         --  If we have operator case, skip quotes since name of operator
2531         --  itself will supply the required quotations. An operator can be an
2532         --  applied use in an expression or an explicit operator symbol, or an
2533         --  identifier whose name indicates it is an operator.
2534
2535         if K in N_Op
2536           or else K = N_Operator_Symbol
2537           or else K = N_Defining_Operator_Symbol
2538           or else ((K = N_Identifier or else K = N_Defining_Identifier)
2539                      and then Is_Operator_Name (Chars (Error_Msg_Node_1)))
2540         then
2541            Set_Msg_Node (Error_Msg_Node_1);
2542
2543         --  Normal case, not an operator, surround with quotes
2544
2545         else
2546            Set_Msg_Quote;
2547            Set_Qualification (Error_Msg_Qual_Level, Error_Msg_Node_1);
2548            Set_Msg_Node (Error_Msg_Node_1);
2549            Set_Msg_Quote;
2550         end if;
2551      end if;
2552
2553      --  The following assignment ensures that a second ampersand insertion
2554      --  character will correspond to the Error_Msg_Node_2 parameter. We
2555      --  suppress possible validity checks in case operating in -gnatVa mode,
2556      --  and Error_Msg_Node_2 is not needed and has not been set.
2557
2558      declare
2559         pragma Suppress (Range_Check);
2560      begin
2561         Error_Msg_Node_1 := Error_Msg_Node_2;
2562      end;
2563   end Set_Msg_Insertion_Node;
2564
2565   --------------------------------------
2566   -- Set_Msg_Insertion_Type_Reference --
2567   --------------------------------------
2568
2569   procedure Set_Msg_Insertion_Type_Reference (Flag : Source_Ptr) is
2570      Ent : Entity_Id;
2571
2572   begin
2573      Set_Msg_Blank;
2574
2575      if Error_Msg_Node_1 = Standard_Void_Type then
2576         Set_Msg_Str ("package or procedure name");
2577         return;
2578
2579      elsif Error_Msg_Node_1 = Standard_Exception_Type then
2580         Set_Msg_Str ("exception name");
2581         return;
2582
2583      elsif     Error_Msg_Node_1 = Any_Access
2584        or else Error_Msg_Node_1 = Any_Array
2585        or else Error_Msg_Node_1 = Any_Boolean
2586        or else Error_Msg_Node_1 = Any_Character
2587        or else Error_Msg_Node_1 = Any_Composite
2588        or else Error_Msg_Node_1 = Any_Discrete
2589        or else Error_Msg_Node_1 = Any_Fixed
2590        or else Error_Msg_Node_1 = Any_Integer
2591        or else Error_Msg_Node_1 = Any_Modular
2592        or else Error_Msg_Node_1 = Any_Numeric
2593        or else Error_Msg_Node_1 = Any_Real
2594        or else Error_Msg_Node_1 = Any_Scalar
2595        or else Error_Msg_Node_1 = Any_String
2596      then
2597         Get_Unqualified_Decoded_Name_String (Chars (Error_Msg_Node_1));
2598         Set_Msg_Name_Buffer;
2599         return;
2600
2601      elsif Error_Msg_Node_1 = Universal_Real then
2602         Set_Msg_Str ("type universal real");
2603         return;
2604
2605      elsif Error_Msg_Node_1 = Universal_Integer then
2606         Set_Msg_Str ("type universal integer");
2607         return;
2608
2609      elsif Error_Msg_Node_1 = Universal_Fixed then
2610         Set_Msg_Str ("type universal fixed");
2611         return;
2612      end if;
2613
2614      --  Special case of anonymous array
2615
2616      if Nkind (Error_Msg_Node_1) in N_Entity
2617        and then Is_Array_Type (Error_Msg_Node_1)
2618        and then Present (Related_Array_Object (Error_Msg_Node_1))
2619      then
2620         Set_Msg_Str ("type of ");
2621         Set_Msg_Node (Related_Array_Object (Error_Msg_Node_1));
2622         Set_Msg_Str (" declared");
2623         Set_Msg_Insertion_Line_Number
2624           (Sloc (Related_Array_Object (Error_Msg_Node_1)), Flag);
2625         return;
2626      end if;
2627
2628      --  If we fall through, it is not a special case, so first output
2629      --  the name of the type, preceded by private for a private type
2630
2631      if Is_Private_Type (Error_Msg_Node_1) then
2632         Set_Msg_Str ("private type ");
2633      else
2634         Set_Msg_Str ("type ");
2635      end if;
2636
2637      Ent := Error_Msg_Node_1;
2638
2639      if Is_Internal_Name (Chars (Ent)) then
2640         Unwind_Internal_Type (Ent);
2641      end if;
2642
2643      --  Types in Standard are displayed as "Standard.name"
2644
2645      if Sloc (Ent) <= Standard_Location then
2646         Set_Msg_Quote;
2647         Set_Msg_Str ("Standard.");
2648         Set_Msg_Node (Ent);
2649         Add_Class;
2650         Set_Msg_Quote;
2651
2652      --  Types in other language defined units are displayed as
2653      --  "package-name.type-name"
2654
2655      elsif
2656        Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (Ent)))
2657      then
2658         Get_Unqualified_Decoded_Name_String
2659           (Unit_Name (Get_Source_Unit (Ent)));
2660         Name_Len := Name_Len - 2;
2661         Set_Msg_Blank_Conditional;
2662         Set_Msg_Quote;
2663         Set_Casing (Mixed_Case);
2664         Set_Msg_Name_Buffer;
2665         Set_Msg_Char ('.');
2666         Set_Casing (Mixed_Case);
2667         Set_Msg_Node (Ent);
2668         Add_Class;
2669         Set_Msg_Quote;
2670
2671      --  All other types display as "type name" defined at line xxx
2672      --  possibly qualified if qualification is requested.
2673
2674      else
2675         Set_Msg_Quote;
2676         Set_Qualification (Error_Msg_Qual_Level, Ent);
2677         Set_Msg_Node (Ent);
2678         Add_Class;
2679
2680         --  If we did not print a name (e.g. in the case of an anonymous
2681         --  subprogram type), there is no name to print, so remove quotes.
2682
2683         if Buffer_Ends_With ('"') then
2684            Buffer_Remove ('"');
2685         else
2686            Set_Msg_Quote;
2687         end if;
2688      end if;
2689
2690      --  If the original type did not come from a predefined file, add the
2691      --  location where the type was defined.
2692
2693      if Sloc (Error_Msg_Node_1) > Standard_Location
2694        and then
2695          not Is_Predefined_File_Name
2696                (Unit_File_Name (Get_Source_Unit (Error_Msg_Node_1)))
2697      then
2698         Set_Msg_Str (" defined");
2699         Set_Msg_Insertion_Line_Number (Sloc (Error_Msg_Node_1), Flag);
2700
2701      --  If it did come from a predefined file, deal with the case where
2702      --  this was a file with a generic instantiation from elsewhere.
2703
2704      else
2705         if Sloc (Error_Msg_Node_1) > Standard_Location then
2706            declare
2707               Iloc : constant Source_Ptr :=
2708                 Instantiation_Location (Sloc (Error_Msg_Node_1));
2709
2710            begin
2711               if Iloc /= No_Location
2712                 and then not Suppress_Instance_Location
2713               then
2714                  Set_Msg_Str (" from instance");
2715                  Set_Msg_Insertion_Line_Number (Iloc, Flag);
2716               end if;
2717            end;
2718         end if;
2719      end if;
2720   end Set_Msg_Insertion_Type_Reference;
2721
2722   ---------------------------------
2723   -- Set_Msg_Insertion_Unit_Name --
2724   ---------------------------------
2725
2726   procedure Set_Msg_Insertion_Unit_Name (Suffix : Boolean := True) is
2727   begin
2728      if Error_Msg_Unit_1 = No_Unit_Name then
2729         null;
2730
2731      elsif Error_Msg_Unit_1 = Error_Unit_Name then
2732         Set_Msg_Blank;
2733         Set_Msg_Str ("<error>");
2734
2735      else
2736         Get_Unit_Name_String (Error_Msg_Unit_1, Suffix);
2737         Set_Msg_Blank;
2738         Set_Msg_Quote;
2739         Set_Msg_Name_Buffer;
2740         Set_Msg_Quote;
2741      end if;
2742
2743      --  The following assignment ensures that a second percent insertion
2744      --  character will correspond to the Error_Msg_Unit_2 parameter. We
2745      --  suppress possible validity checks in case operating in -gnatVa mode,
2746      --  and Error_Msg_Unit_2 is not needed and has not been set.
2747
2748      declare
2749         pragma Suppress (Range_Check);
2750      begin
2751         Error_Msg_Unit_1 := Error_Msg_Unit_2;
2752      end;
2753   end Set_Msg_Insertion_Unit_Name;
2754
2755   ------------------
2756   -- Set_Msg_Node --
2757   ------------------
2758
2759   procedure Set_Msg_Node (Node : Node_Id) is
2760      Loc : Source_Ptr;
2761      Ent : Entity_Id;
2762      Nam : Name_Id;
2763
2764   begin
2765      case Nkind (Node) is
2766         when N_Designator =>
2767            Set_Msg_Node (Name (Node));
2768            Set_Msg_Char ('.');
2769            Set_Msg_Node (Identifier (Node));
2770            return;
2771
2772         when N_Defining_Program_Unit_Name =>
2773            Set_Msg_Node (Name (Node));
2774            Set_Msg_Char ('.');
2775            Set_Msg_Node (Defining_Identifier (Node));
2776            return;
2777
2778         when N_Selected_Component | N_Expanded_Name =>
2779            Set_Msg_Node (Prefix (Node));
2780            Set_Msg_Char ('.');
2781            Set_Msg_Node (Selector_Name (Node));
2782            return;
2783
2784         when others =>
2785            null;
2786      end case;
2787
2788      --  The only remaining possibilities are identifiers, defining
2789      --  identifiers, pragmas, and pragma argument associations.
2790
2791      if Nkind (Node) = N_Pragma then
2792         Nam := Pragma_Name (Node);
2793         Loc := Sloc (Node);
2794
2795      --  The other cases have Chars fields
2796
2797      --  First deal with internal names, which generally represent something
2798      --  gone wrong. First attempt: if this is a rewritten node that rewrites
2799      --  something with a Chars field that is not an internal name, use that.
2800
2801      elsif Is_Internal_Name (Chars (Node))
2802        and then Nkind (Original_Node (Node)) in N_Has_Chars
2803        and then not Is_Internal_Name (Chars (Original_Node (Node)))
2804      then
2805         Nam := Chars (Original_Node (Node));
2806         Loc := Sloc (Original_Node (Node));
2807
2808      --  Another shot for internal names, in the case of internal type names,
2809      --  we try to find a reasonable representation for the external name.
2810
2811      elsif Is_Internal_Name (Chars (Node))
2812        and then
2813          ((Is_Entity_Name (Node)
2814             and then Present (Entity (Node))
2815             and then Is_Type (Entity (Node)))
2816            or else
2817             (Nkind (Node) = N_Defining_Identifier and then Is_Type (Node)))
2818      then
2819         if Nkind (Node) = N_Identifier then
2820            Ent := Entity (Node);
2821         else
2822            Ent := Node;
2823         end if;
2824
2825         Loc := Sloc (Ent);
2826
2827         --  If the type is the designated type of an access_to_subprogram,
2828         --  then there is no name to provide in the call.
2829
2830         if Ekind (Ent) = E_Subprogram_Type then
2831            return;
2832
2833         --  Otherwise, we will be able to find some kind of name to output
2834
2835         else
2836            Unwind_Internal_Type (Ent);
2837            Nam := Chars (Ent);
2838         end if;
2839
2840      --  If not internal name, or if we could not find a reasonable possible
2841      --  substitution for the internal name, just use name in Chars field.
2842
2843      else
2844         Nam := Chars (Node);
2845         Loc := Sloc (Node);
2846      end if;
2847
2848      --  At this stage, the name to output is in Nam
2849
2850      Get_Unqualified_Decoded_Name_String (Nam);
2851
2852      --  Remove trailing upper case letters from the name (useful for
2853      --  dealing with some cases of internal names).
2854
2855      while Name_Len > 1 and then Name_Buffer (Name_Len) in 'A' .. 'Z' loop
2856         Name_Len := Name_Len  - 1;
2857      end loop;
2858
2859      --  If we have any of the names from standard that start with the
2860      --  characters "any " (e.g. Any_Type), then kill the message since
2861      --  almost certainly it is a junk cascaded message.
2862
2863      if Name_Len > 4
2864        and then Name_Buffer (1 .. 4) = "any "
2865      then
2866         Kill_Message := True;
2867      end if;
2868
2869      --  If we still have an internal name, kill the message (will only
2870      --  work if we already had errors!)
2871
2872      if Is_Internal_Name then
2873         Kill_Message := True;
2874      end if;
2875      --  Remaining step is to adjust casing and possibly add 'Class
2876
2877      Adjust_Name_Case (Loc);
2878      Set_Msg_Name_Buffer;
2879      Add_Class;
2880   end Set_Msg_Node;
2881
2882   ------------------
2883   -- Set_Msg_Text --
2884   ------------------
2885
2886   procedure Set_Msg_Text (Text : String; Flag : Source_Ptr) is
2887      C : Character;   -- Current character
2888      P : Natural;     -- Current index;
2889
2890      procedure Skip_Msg_Insertion_Warning (C : Character);
2891      --  Deal with ? ?? ?x? ?X? ?*? ?$? insertion sequences (and the same
2892      --  sequences using < instead of ?). The caller has already bumped
2893      --  the pointer past the initial ? or < and C is set to this initial
2894      --  character (? or <). This procedure skips past the rest of the
2895      --  sequence. We do not need to set Msg_Insertion_Char, since this
2896      --  was already done during the message prescan.
2897
2898      --------------------------------
2899      -- Skip_Msg_Insertion_Warning --
2900      --------------------------------
2901
2902      procedure Skip_Msg_Insertion_Warning (C : Character) is
2903      begin
2904         if P <= Text'Last and then Text (P) = C then
2905            P := P + 1;
2906
2907         elsif P + 1 <= Text'Last
2908           and then (Text (P) in 'a' .. 'z'
2909                       or else
2910                     Text (P) in 'A' .. 'Z'
2911                       or else
2912                     Text (P) = '*'
2913                       or else
2914                     Text (P) = '$')
2915           and then Text (P + 1) = C
2916         then
2917            P := P + 2;
2918         end if;
2919      end Skip_Msg_Insertion_Warning;
2920
2921   --  Start of processing for Set_Msg_Text
2922
2923   begin
2924      Manual_Quote_Mode := False;
2925      Msglen := 0;
2926      Flag_Source := Get_Source_File_Index (Flag);
2927
2928      --  Skip info: at start, we have recorded this in Is_Info_Msg, and this
2929      --  will be used (Info field in error message object) to put back the
2930      --  string when it is printed. We need to do this, or we get confused
2931      --  with instantiation continuations.
2932
2933      if Text'Length > 6
2934        and then Text (Text'First .. Text'First + 5) = "info: "
2935      then
2936         P := Text'First + 6;
2937      else
2938         P := Text'First;
2939      end if;
2940
2941      --  Loop through characters of message
2942
2943      while P <= Text'Last loop
2944         C := Text (P);
2945         P := P + 1;
2946
2947         --  Check for insertion character or sequence
2948
2949         case C is
2950            when '%' =>
2951               if P <= Text'Last and then Text (P) = '%' then
2952                  P := P + 1;
2953                  Set_Msg_Insertion_Name_Literal;
2954               else
2955                  Set_Msg_Insertion_Name;
2956               end if;
2957
2958            when '$' =>
2959               if P <= Text'Last and then Text (P) = '$' then
2960                  P := P + 1;
2961                  Set_Msg_Insertion_Unit_Name (Suffix => False);
2962               else
2963                  Set_Msg_Insertion_Unit_Name;
2964               end if;
2965
2966            when '{' =>
2967               Set_Msg_Insertion_File_Name;
2968
2969            when '}' =>
2970               Set_Msg_Insertion_Type_Reference (Flag);
2971
2972            when '*' =>
2973               Set_Msg_Insertion_Reserved_Name;
2974
2975            when '&' =>
2976               Set_Msg_Insertion_Node;
2977
2978            when '#' =>
2979               Set_Msg_Insertion_Line_Number (Error_Msg_Sloc, Flag);
2980
2981            when '\' =>
2982               Continuation := True;
2983
2984               if Text (P) = '\' then
2985                  Continuation_New_Line := True;
2986                  P := P + 1;
2987               end if;
2988
2989            when '@' =>
2990               Set_Msg_Insertion_Column;
2991
2992            when '>' =>
2993               Set_Msg_Insertion_Run_Time_Name;
2994
2995            when '^' =>
2996               Set_Msg_Insertion_Uint;
2997
2998            when '`' =>
2999               Manual_Quote_Mode := not Manual_Quote_Mode;
3000               Set_Msg_Char ('"');
3001
3002            when '!' =>
3003               null; -- already dealt with
3004
3005            when '?' =>
3006               Skip_Msg_Insertion_Warning ('?');
3007
3008            when '<' =>
3009               Skip_Msg_Insertion_Warning ('<');
3010
3011            when '|' =>
3012               null; -- already dealt with
3013
3014            when ''' =>
3015               Set_Msg_Char (Text (P));
3016               P := P + 1;
3017
3018            when '~' =>
3019               Set_Msg_Str (Error_Msg_String (1 .. Error_Msg_Strlen));
3020
3021            --  Upper case letter
3022
3023            when 'A' .. 'Z' =>
3024
3025               --  Start of reserved word if two or more
3026
3027               if P <= Text'Last and then Text (P) in 'A' .. 'Z' then
3028                  P := P - 1;
3029                  Set_Msg_Insertion_Reserved_Word (Text, P);
3030
3031               --  Single upper case letter is just inserted
3032
3033               else
3034                  Set_Msg_Char (C);
3035               end if;
3036
3037            --  '[' (will be/would have been raised at run time)
3038
3039            when '[' =>
3040               if Is_Warning_Msg then
3041                  Set_Msg_Str ("will be raised at run time");
3042               else
3043                  Set_Msg_Str ("would have been raised at run time");
3044               end if;
3045
3046            --   ']' (may be/might have been raised at run time)
3047
3048            when ']' =>
3049               if Is_Warning_Msg then
3050                  Set_Msg_Str ("may be raised at run time");
3051               else
3052                  Set_Msg_Str ("might have been raised at run time");
3053               end if;
3054
3055            --  Normal character with no special treatment
3056
3057            when others =>
3058               Set_Msg_Char (C);
3059         end case;
3060      end loop;
3061   end Set_Msg_Text;
3062
3063   ----------------
3064   -- Set_Posted --
3065   ----------------
3066
3067   procedure Set_Posted (N : Node_Id) is
3068      P : Node_Id;
3069
3070   begin
3071      if Is_Serious_Error then
3072
3073         --  We always set Error_Posted on the node itself
3074
3075         Set_Error_Posted (N);
3076
3077         --  If it is a subexpression, then set Error_Posted on parents up to
3078         --  and including the first non-subexpression construct. This helps
3079         --  avoid cascaded error messages within a single expression.
3080
3081         P := N;
3082         loop
3083            P := Parent (P);
3084            exit when No (P);
3085            Set_Error_Posted (P);
3086            exit when Nkind (P) not in N_Subexpr;
3087         end loop;
3088
3089         if Nkind_In (P, N_Pragma_Argument_Association,
3090                         N_Component_Association,
3091                         N_Discriminant_Association,
3092                         N_Generic_Association,
3093                         N_Parameter_Association)
3094         then
3095            Set_Error_Posted (Parent (P));
3096         end if;
3097
3098         --  A special check, if we just posted an error on an attribute
3099         --  definition clause, then also set the entity involved as posted.
3100         --  For example, this stops complaining about the alignment after
3101         --  complaining about the size, which is likely to be useless.
3102
3103         if Nkind (P) = N_Attribute_Definition_Clause then
3104            if Is_Entity_Name (Name (P)) then
3105               Set_Error_Posted (Entity (Name (P)));
3106            end if;
3107         end if;
3108      end if;
3109   end Set_Posted;
3110
3111   -----------------------
3112   -- Set_Qualification --
3113   -----------------------
3114
3115   procedure Set_Qualification (N : Nat; E : Entity_Id) is
3116   begin
3117      if N /= 0 and then Scope (E) /= Standard_Standard then
3118         Set_Qualification (N - 1, Scope (E));
3119         Set_Msg_Node (Scope (E));
3120         Set_Msg_Char ('.');
3121      end if;
3122   end Set_Qualification;
3123
3124   ------------------------
3125   -- Special_Msg_Delete --
3126   ------------------------
3127
3128   --  Is it really right to have all this specialized knowledge in errout?
3129
3130   function Special_Msg_Delete
3131     (Msg : String;
3132      N   : Node_Or_Entity_Id;
3133      E   : Node_Or_Entity_Id) return Boolean
3134   is
3135   begin
3136      --  Never delete messages in -gnatdO mode
3137
3138      if Debug_Flag_OO then
3139         return False;
3140
3141      --  Processing for "atomic access cannot be guaranteed"
3142
3143      elsif Msg = "atomic access to & cannot be guaranteed" then
3144
3145         --  When an atomic object refers to a non-atomic type in the same
3146         --  scope, we implicitly make the type atomic. In the non-error case
3147         --  this is surely safe (and in fact prevents an error from occurring
3148         --  if the type is not atomic by default). But if the object cannot be
3149         --  made atomic, then we introduce an extra junk message by this
3150         --  manipulation, which we get rid of here.
3151
3152         --  We identify this case by the fact that it references a type for
3153         --  which Is_Atomic is set, but there is no Atomic pragma setting it.
3154
3155         if Is_Type (E)
3156           and then Is_Atomic (E)
3157           and then No (Get_Rep_Pragma (E, Name_Atomic))
3158         then
3159            return True;
3160         end if;
3161
3162      --  Similar processing for "volatile full access cannot be guaranteed"
3163
3164      elsif Msg = "volatile full access to & cannot be guaranteed" then
3165         if Is_Type (E)
3166           and then Is_Volatile_Full_Access (E)
3167           and then No (Get_Rep_Pragma (E, Name_Volatile_Full_Access))
3168         then
3169            return True;
3170         end if;
3171
3172      --  Processing for "Size too small" messages
3173
3174      elsif Msg = "size for& too small, minimum allowed is ^" then
3175
3176         --  Suppress "size too small" errors in CodePeer mode, since code may
3177         --  be analyzed in a different configuration than the one used for
3178         --  compilation. Even when the configurations match, this message
3179         --  may be issued on correct code, because pragma Pack is ignored
3180         --  in CodePeer mode.
3181
3182         if CodePeer_Mode then
3183            return True;
3184
3185         --  When a size is wrong for a frozen type there is no explicit size
3186         --  clause, and other errors have occurred, suppress the message,
3187         --  since it is likely that this size error is a cascaded result of
3188         --  other errors. The reason we eliminate unfrozen types is that
3189         --  messages issued before the freeze type are for sure OK.
3190
3191         elsif Is_Frozen (E)
3192           and then Serious_Errors_Detected > 0
3193           and then Nkind (N) /= N_Component_Clause
3194           and then Nkind (Parent (N)) /= N_Component_Clause
3195           and then
3196             No (Get_Attribute_Definition_Clause (E, Attribute_Size))
3197           and then
3198             No (Get_Attribute_Definition_Clause (E, Attribute_Object_Size))
3199           and then
3200             No (Get_Attribute_Definition_Clause (E, Attribute_Value_Size))
3201         then
3202            return True;
3203         end if;
3204      end if;
3205
3206      --  All special tests complete, so go ahead with message
3207
3208      return False;
3209   end Special_Msg_Delete;
3210
3211   -----------------
3212   -- SPARK_Msg_N --
3213   -----------------
3214
3215   procedure SPARK_Msg_N (Msg : String; N : Node_Or_Entity_Id) is
3216   begin
3217      if SPARK_Mode /= Off then
3218         Error_Msg_N (Msg, N);
3219      end if;
3220   end SPARK_Msg_N;
3221
3222   ------------------
3223   -- SPARK_Msg_NE --
3224   ------------------
3225
3226   procedure SPARK_Msg_NE
3227     (Msg : String;
3228      N   : Node_Or_Entity_Id;
3229      E   : Node_Or_Entity_Id)
3230   is
3231   begin
3232      if SPARK_Mode /= Off then
3233         Error_Msg_NE (Msg, N, E);
3234      end if;
3235   end SPARK_Msg_NE;
3236
3237   --------------------------
3238   -- Unwind_Internal_Type --
3239   --------------------------
3240
3241   procedure Unwind_Internal_Type (Ent : in out Entity_Id) is
3242      Derived : Boolean := False;
3243      Mchar   : Character;
3244      Old_Ent : Entity_Id;
3245
3246   begin
3247      --  Undo placement of a quote, since we will put it back later
3248
3249      Mchar := Msg_Buffer (Msglen);
3250
3251      if Mchar = '"' then
3252         Msglen := Msglen - 1;
3253      end if;
3254
3255      --  The loop here deals with recursive types, we are trying to find a
3256      --  related entity that is not an implicit type. Note that the check with
3257      --  Old_Ent stops us from getting "stuck". Also, we don't output the
3258      --  "type derived from" message more than once in the case where we climb
3259      --  up multiple levels.
3260
3261      Find : loop
3262         Old_Ent := Ent;
3263
3264         --  Implicit access type, use directly designated type In Ada 2005,
3265         --  the designated type may be an anonymous access to subprogram, in
3266         --  which case we can only point to its definition.
3267
3268         if Is_Access_Type (Ent) then
3269            if Ekind (Ent) = E_Access_Subprogram_Type
3270              or else Ekind (Ent) = E_Anonymous_Access_Subprogram_Type
3271              or else Is_Access_Protected_Subprogram_Type (Ent)
3272            then
3273               Ent := Directly_Designated_Type (Ent);
3274
3275               if not Comes_From_Source (Ent) then
3276                  if Buffer_Ends_With ("type ") then
3277                     Buffer_Remove ("type ");
3278                  end if;
3279               end if;
3280
3281               if Ekind (Ent) = E_Function then
3282                  Set_Msg_Str ("access to function ");
3283               elsif Ekind (Ent) = E_Procedure then
3284                  Set_Msg_Str ("access to procedure ");
3285               else
3286                  Set_Msg_Str ("access to subprogram");
3287               end if;
3288
3289               exit Find;
3290
3291            --  Type is access to object, named or anonymous
3292
3293            else
3294               Set_Msg_Str ("access to ");
3295               Ent := Directly_Designated_Type (Ent);
3296            end if;
3297
3298         --  Classwide type
3299
3300         elsif Is_Class_Wide_Type (Ent) then
3301            Class_Flag := True;
3302            Ent := Root_Type (Ent);
3303
3304         --  Use base type if this is a subtype
3305
3306         elsif Ent /= Base_Type (Ent) then
3307            Buffer_Remove ("type ");
3308
3309            --  Avoid duplication "subtype of subtype of", and also replace
3310            --  "derived from subtype of" simply by "derived from"
3311
3312            if not Buffer_Ends_With ("subtype of ")
3313              and then not Buffer_Ends_With ("derived from ")
3314            then
3315               Set_Msg_Str ("subtype of ");
3316            end if;
3317
3318            Ent := Base_Type (Ent);
3319
3320         --  If this is a base type with a first named subtype, use the first
3321         --  named subtype instead. This is not quite accurate in all cases,
3322         --  but it makes too much noise to be accurate and add 'Base in all
3323         --  cases. Note that we only do this is the first named subtype is not
3324         --  itself an internal name. This avoids the obvious loop (subtype ->
3325         --  basetype -> subtype) which would otherwise occur).
3326
3327         else
3328            declare
3329               FST : constant Entity_Id := First_Subtype (Ent);
3330
3331            begin
3332               if not Is_Internal_Name (Chars (FST)) then
3333                  Ent := FST;
3334                  exit Find;
3335
3336                  --  Otherwise use root type
3337
3338               else
3339                  if not Derived then
3340                     Buffer_Remove ("type ");
3341
3342                     --  Test for "subtype of type derived from" which seems
3343                     --  excessive and is replaced by "type derived from".
3344
3345                     Buffer_Remove ("subtype of");
3346
3347                     --  Avoid duplicated "type derived from type derived from"
3348
3349                     if not Buffer_Ends_With ("type derived from ") then
3350                        Set_Msg_Str ("type derived from ");
3351                     end if;
3352
3353                     Derived := True;
3354                  end if;
3355               end if;
3356            end;
3357
3358            Ent := Etype (Ent);
3359         end if;
3360
3361         --  If we are stuck in a loop, get out and settle for the internal
3362         --  name after all. In this case we set to kill the message if it is
3363         --  not the first error message (we really try hard not to show the
3364         --  dirty laundry of the implementation to the poor user).
3365
3366         if Ent = Old_Ent then
3367            Kill_Message := True;
3368            exit Find;
3369         end if;
3370
3371         --  Get out if we finally found a non-internal name to use
3372
3373         exit Find when not Is_Internal_Name (Chars (Ent));
3374      end loop Find;
3375
3376      if Mchar = '"' then
3377         Set_Msg_Char ('"');
3378      end if;
3379   end Unwind_Internal_Type;
3380
3381   --------------------
3382   -- Warn_Insertion --
3383   --------------------
3384
3385   function Warn_Insertion return String is
3386   begin
3387      case Warning_Msg_Char is
3388         when '?' =>
3389            return "??";
3390         when 'a' .. 'z' | 'A' .. 'Z' | '*' | '$' =>
3391            return '?' & Warning_Msg_Char & '?';
3392         when ' ' =>
3393            return "?";
3394         when others =>
3395            raise Program_Error;
3396      end case;
3397   end Warn_Insertion;
3398
3399end Errout;
3400