1------------------------------------------------------------------------------
2--                                                                          --
3--                         GNAT COMPILER COMPONENTS                         --
4--                                                                          --
5--                              C O M P E R R                               --
6--                                                                          --
7--                                 B o d y                                  --
8--                                                                          --
9--          Copyright (C) 1992-2014, 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 AdaCore.                         --
23--                                                                          --
24------------------------------------------------------------------------------
25
26--  This package contains routines called when a fatal internal compiler error
27--  is detected. Calls to these routines cause termination of the current
28--  compilation with appropriate error output.
29
30with Atree;    use Atree;
31with Debug;    use Debug;
32with Errout;   use Errout;
33with Gnatvsn;  use Gnatvsn;
34with Lib;      use Lib;
35with Namet;    use Namet;
36with Opt;      use Opt;
37with Osint;    use Osint;
38with Output;   use Output;
39with Sinfo;    use Sinfo;
40with Sinput;   use Sinput;
41with Sprint;   use Sprint;
42with Sdefault; use Sdefault;
43with Targparm; use Targparm;
44with Treepr;   use Treepr;
45with Types;    use Types;
46
47with Ada.Exceptions; use Ada.Exceptions;
48
49with System.OS_Lib;     use System.OS_Lib;
50with System.Soft_Links; use System.Soft_Links;
51
52package body Comperr is
53
54   ----------------
55   -- Local Data --
56   ----------------
57
58   Abort_In_Progress : Boolean := False;
59   --  Used to prevent runaway recursion if something segfaults
60   --  while processing a previous abort.
61
62   -----------------------
63   -- Local Subprograms --
64   -----------------------
65
66   procedure Repeat_Char (Char : Character; Col : Nat; After : Character);
67   --  Output Char until current column is at or past Col, and then output
68   --  the character given by After (if column is already past Col on entry,
69   --  then the effect is simply to output the After character).
70
71   --------------------
72   -- Compiler_Abort --
73   --------------------
74
75   procedure Compiler_Abort
76     (X            : String;
77      Fallback_Loc : String  := "";
78      From_GCC     : Boolean := False)
79   is
80      --  The procedures below output a "bug box" with information about
81      --  the cause of the compiler abort and about the preferred method
82      --  of reporting bugs. The default is a bug box appropriate for
83      --  the FSF version of GNAT, but there are specializations for
84      --  the GNATPRO and Public releases by AdaCore.
85
86      XF : constant Positive := X'First;
87      --  Start index, usually 1, but we won't assume this
88
89      procedure End_Line;
90      --  Add blanks up to column 76, and then a final vertical bar
91
92      --------------
93      -- End_Line --
94      --------------
95
96      procedure End_Line is
97      begin
98         Repeat_Char (' ', 76, '|');
99         Write_Eol;
100      end End_Line;
101
102      Is_GPL_Version : constant Boolean := Gnatvsn.Build_Type = GPL;
103      Is_FSF_Version : constant Boolean := Gnatvsn.Build_Type = FSF;
104
105   --  Start of processing for Compiler_Abort
106
107   begin
108      Cancel_Special_Output;
109
110      --  Prevent recursion through Compiler_Abort, e.g. via SIGSEGV
111
112      if Abort_In_Progress then
113         Exit_Program (E_Abort);
114      end if;
115
116      Abort_In_Progress := True;
117
118      --  Generate a "standard" error message instead of a bug box in case
119      --  of .NET compiler, since we do not support all constructs of the
120      --  language. Of course ideally, we should detect this before bombing on
121      --  e.g. an assertion error, but in practice most of these bombs are due
122      --  to a legitimate case of a construct not being supported (in a sense
123      --  they all are, since for sure we are not supporting something if we
124      --  bomb). By giving this message, we provide a more reasonable practical
125      --  interface, since giving scary bug boxes on unsupported features is
126      --  definitely not helpful.
127
128      --  Similarly if we are generating SCIL, an error message is sufficient
129      --  instead of generating a bug box.
130
131      --  Note that the call to Error_Msg_N below sets Serious_Errors_Detected
132      --  to 1, so we use the regular mechanism below in order to display a
133      --  "compilation abandoned" message and exit, so we still know we have
134      --  this case (and -gnatdk can still be used to get the bug box).
135
136      if (VM_Target = CLI_Target or else CodePeer_Mode)
137        and then Serious_Errors_Detected = 0
138        and then not Debug_Flag_K
139        and then Sloc (Current_Error_Node) > No_Location
140      then
141         if VM_Target = CLI_Target then
142            Error_Msg_N
143              ("unsupported construct in this context",
144               Current_Error_Node);
145         else
146            Error_Msg_N ("cannot generate 'S'C'I'L", Current_Error_Node);
147         end if;
148      end if;
149
150      --  If we are in CodePeer mode, we must also delete SCIL files
151
152      if CodePeer_Mode then
153         Delete_SCIL_Files;
154      end if;
155
156      --  If any errors have already occurred, then we guess that the abort
157      --  may well be caused by previous errors, and we don't make too much
158      --  fuss about it, since we want to let programmer fix the errors first.
159
160      --  Debug flag K disables this behavior (useful for debugging)
161
162      if Serious_Errors_Detected /= 0 and then not Debug_Flag_K then
163         Errout.Finalize (Last_Call => True);
164         Errout.Output_Messages;
165
166         Set_Standard_Error;
167         Write_Str ("compilation abandoned due to previous error");
168         Write_Eol;
169
170         Set_Standard_Output;
171         Source_Dump;
172         Tree_Dump;
173         Exit_Program (E_Errors);
174
175      --  Otherwise give message with details of the abort
176
177      else
178         Set_Standard_Error;
179
180         --  Generate header for bug box
181
182         Write_Char ('+');
183         Repeat_Char ('=', 29, 'G');
184         Write_Str ("NAT BUG DETECTED");
185         Repeat_Char ('=', 76, '+');
186         Write_Eol;
187
188         --  Output GNAT version identification
189
190         Write_Str ("| ");
191         Write_Str (Gnat_Version_String);
192         Write_Str (" (");
193
194         --  Output target name, deleting junk final reverse slash
195
196         if Target_Name.all (Target_Name.all'Last) = '\'
197           or else Target_Name.all (Target_Name.all'Last) = '/'
198         then
199            Write_Str (Target_Name.all (1 .. Target_Name.all'Last - 1));
200         else
201            Write_Str (Target_Name.all);
202         end if;
203
204         --  Output identification of error
205
206         Write_Str (") ");
207
208         if X'Length + Column > 76 then
209            if From_GCC then
210               Write_Str ("GCC error:");
211            end if;
212
213            End_Line;
214
215            Write_Str ("| ");
216         end if;
217
218         if X'Length > 70 then
219            declare
220               Last_Blank : Integer := 70;
221
222            begin
223               for P in 39 .. 68 loop
224                  if X (XF + P) = ' ' then
225                     Last_Blank := P;
226                  end if;
227               end loop;
228
229               Write_Str (X (XF .. XF - 1 + Last_Blank));
230               End_Line;
231               Write_Str ("|    ");
232               Write_Str (X (XF + Last_Blank .. X'Last));
233            end;
234         else
235            Write_Str (X);
236         end if;
237
238         if not From_GCC then
239
240            --  For exception case, get exception message from the TSD. Note
241            --  that it would be neater and cleaner to pass the exception
242            --  message (obtained from Exception_Message) as a parameter to
243            --  Compiler_Abort, but we can't do this quite yet since it would
244            --  cause bootstrap path problems for 3.10 to 3.11.
245
246            Write_Char (' ');
247            Write_Str (Exception_Message (Get_Current_Excep.all.all));
248         end if;
249
250         End_Line;
251
252         --  Output source location information
253
254         if Sloc (Current_Error_Node) <= No_Location then
255            if Fallback_Loc'Length > 0 then
256               Write_Str ("| Error detected around ");
257               Write_Str (Fallback_Loc);
258            else
259               Write_Str ("| No source file position information available");
260            end if;
261
262            End_Line;
263         else
264            Write_Str ("| Error detected at ");
265            Write_Location (Sloc (Current_Error_Node));
266            End_Line;
267         end if;
268
269         --  There are two cases now. If the file gnat_bug.box exists,
270         --  we use the contents of this file at this point.
271
272         declare
273            Lo  : Source_Ptr;
274            Hi  : Source_Ptr;
275            Src : Source_Buffer_Ptr;
276
277         begin
278            Namet.Unlock;
279            Name_Buffer (1 .. 12) := "gnat_bug.box";
280            Name_Len := 12;
281            Read_Source_File (Name_Enter, 0, Hi, Src);
282
283            --  If we get a Src file, we use it
284
285            if Src /= null then
286               Lo := 0;
287
288               Outer : while Lo < Hi loop
289                  Write_Str ("| ");
290
291                  Inner : loop
292                     exit Inner when Src (Lo) = ASCII.CR
293                       or else Src (Lo) = ASCII.LF;
294                     Write_Char (Src (Lo));
295                     Lo := Lo + 1;
296                  end loop Inner;
297
298                  End_Line;
299
300                  while Lo <= Hi
301                    and then (Src (Lo) = ASCII.CR
302                                or else Src (Lo) = ASCII.LF)
303                  loop
304                     Lo := Lo + 1;
305                  end loop;
306               end loop Outer;
307
308            --  Otherwise we use the standard fixed text
309
310            else
311               if Is_FSF_Version then
312                  Write_Str
313                    ("| Please submit a bug report; see" &
314                     " http://gcc.gnu.org/bugs.html.");
315                  End_Line;
316
317               elsif Is_GPL_Version then
318
319                  Write_Str
320                    ("| Please submit a bug report by email " &
321                     "to report@adacore.com.");
322                  End_Line;
323
324                  Write_Str
325                    ("| GAP members can alternatively use GNAT Tracker:");
326                  End_Line;
327
328                  Write_Str
329                    ("| http://www.adacore.com/ " &
330                     "section 'send a report'.");
331                  End_Line;
332
333                  Write_Str
334                    ("| See gnatinfo.txt for full info on procedure " &
335                     "for submitting bugs.");
336                  End_Line;
337
338               else
339                  Write_Str
340                    ("| Please submit a bug report using GNAT Tracker:");
341                  End_Line;
342
343                  Write_Str
344                    ("| http://www.adacore.com/gnattracker/ " &
345                     "section 'send a report'.");
346                  End_Line;
347
348                  Write_Str
349                    ("| alternatively submit a bug report by email " &
350                     "to report@adacore.com,");
351                  End_Line;
352
353                  Write_Str
354                    ("| including your customer number #nnn " &
355                     "in the subject line.");
356                  End_Line;
357               end if;
358
359               Write_Str
360                 ("| Use a subject line meaningful to you" &
361                  " and us to track the bug.");
362               End_Line;
363
364               Write_Str
365                 ("| Include the entire contents of this bug " &
366                  "box in the report.");
367               End_Line;
368
369               Write_Str
370                 ("| Include the exact gcc or gnatmake command " &
371                  "that you entered.");
372               End_Line;
373
374               Write_Str
375                 ("| Also include sources listed below in gnatchop format");
376               End_Line;
377
378               Write_Str
379                 ("| (concatenated together with no headers between files).");
380               End_Line;
381
382               if not Is_FSF_Version then
383                  Write_Str
384                    ("| Use plain ASCII or MIME attachment.");
385                  End_Line;
386               end if;
387            end if;
388         end;
389
390         --  Complete output of bug box
391
392         Write_Char ('+');
393         Repeat_Char ('=', 76, '+');
394         Write_Eol;
395
396         if Debug_Flag_3 then
397            Write_Eol;
398            Write_Eol;
399            Print_Tree_Node (Current_Error_Node);
400            Write_Eol;
401         end if;
402
403         Write_Eol;
404
405         Write_Line ("Please include these source files with error report");
406         Write_Line ("Note that list may not be accurate in some cases, ");
407         Write_Line ("so please double check that the problem can still ");
408         Write_Line ("be reproduced with the set of files listed.");
409         Write_Line ("Consider also -gnatd.n switch (see debug.adb).");
410         Write_Eol;
411
412         begin
413            Dump_Source_File_Names;
414
415         --  If we blow up trying to print the list of file names, just output
416         --  informative msg and continue.
417
418         exception
419            when others =>
420               Write_Str ("list may be incomplete");
421         end;
422
423         Write_Eol;
424         Set_Standard_Output;
425
426         Tree_Dump;
427         Source_Dump;
428         raise Unrecoverable_Error;
429      end if;
430   end Compiler_Abort;
431
432   -----------------------
433   -- Delete_SCIL_Files --
434   -----------------------
435
436   procedure Delete_SCIL_Files is
437      Main      : Node_Id;
438      Unit_Name : Node_Id;
439
440      Success : Boolean;
441      pragma Unreferenced (Success);
442
443      procedure Decode_Name_Buffer;
444      --  Replace "__" by "." in Name_Buffer, and adjust Name_Len accordingly
445
446      ------------------------
447      -- Decode_Name_Buffer --
448      ------------------------
449
450      procedure Decode_Name_Buffer is
451         J : Natural;
452         K : Natural;
453
454      begin
455         J := 1;
456         K := 0;
457         while J <= Name_Len loop
458            K := K + 1;
459
460            if J < Name_Len
461              and then Name_Buffer (J) = '_'
462              and then Name_Buffer (J + 1) = '_'
463            then
464               Name_Buffer (K) := '.';
465               J := J + 1;
466            else
467               Name_Buffer (K) := Name_Buffer (J);
468            end if;
469
470            J := J + 1;
471         end loop;
472
473         Name_Len := K;
474      end Decode_Name_Buffer;
475
476   --  Start of processing for Delete_SCIL_Files
477
478   begin
479      --  If parsing was not successful, no Main_Unit is available, so return
480      --  immediately.
481
482      if Main_Source_File = No_Source_File then
483         return;
484      end if;
485
486      --  Retrieve unit name, and remove old versions of SCIL/<unit>.scil and
487      --  SCIL/<unit>__body.scil, ditto for .scilx files.
488
489      Main := Unit (Cunit (Main_Unit));
490
491      case Nkind (Main) is
492         when N_Subprogram_Body | N_Package_Declaration =>
493            Unit_Name := Defining_Unit_Name (Specification (Main));
494
495         when N_Package_Body =>
496            Unit_Name := Corresponding_Spec (Main);
497
498         when N_Package_Renaming_Declaration =>
499            Unit_Name := Defining_Unit_Name (Main);
500
501         --  No SCIL file generated for generic package declarations
502
503         when N_Generic_Package_Declaration =>
504            return;
505
506         --  Should never happen, but can be ignored in production
507
508         when others =>
509            pragma Assert (False);
510            return;
511      end case;
512
513      case Nkind (Unit_Name) is
514         when N_Defining_Identifier =>
515            Get_Name_String (Chars (Unit_Name));
516
517         when N_Defining_Program_Unit_Name =>
518            Get_Name_String (Chars (Defining_Identifier (Unit_Name)));
519            Decode_Name_Buffer;
520
521         --  Should never happen, but can be ignored in production
522
523         when others =>
524            pragma Assert (False);
525            return;
526      end case;
527
528      Delete_File
529        ("SCIL/" & Name_Buffer (1 .. Name_Len) & ".scil", Success);
530      Delete_File
531        ("SCIL/" & Name_Buffer (1 .. Name_Len) & ".scilx", Success);
532      Delete_File
533        ("SCIL/" & Name_Buffer (1 .. Name_Len) & "__body.scil", Success);
534      Delete_File
535        ("SCIL/" & Name_Buffer (1 .. Name_Len) & "__body.scilx", Success);
536   end Delete_SCIL_Files;
537
538   -----------------
539   -- Repeat_Char --
540   -----------------
541
542   procedure Repeat_Char (Char : Character; Col : Nat; After : Character) is
543   begin
544      while Column < Col loop
545         Write_Char (Char);
546      end loop;
547
548      Write_Char (After);
549   end Repeat_Char;
550
551end Comperr;
552