gcc/ada/g-traceb.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT RUN-TIME COMPONENTS                         --
   4 --                                                                          --
   5 --                       G N A T . T R A C E B A C K                        --
   6 --                                                                          --
   7 --                                 S p e c                                  --
   8 --                                                                          --
   9 --                                                                          --
  10 --           Copyright (C) 1999-2001 Ada Core Technologies, Inc.            --
  11 --                                                                          --
  12 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
  13 -- terms of the  GNU General Public License as published  by the Free Soft- --
  14 -- ware  Foundation;  either version 2,  or (at your option) any later ver- --
  15 -- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
  16 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  17 -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
  18 -- for  more details.  You should have  received  a copy of the GNU General --
  19 -- Public License  distributed with GNAT;  see file COPYING.  If not, write --
  20 -- to  the Free Software Foundation,  59 Temple Place - Suite 330,  Boston, --
  21 -- MA 02111-1307, USA.                                                      --
  22 --                                                                          --
  23 -- As a special exception,  if other files  instantiate  generics from this --
  24 -- unit, or you link  this unit with other files  to produce an executable, --
  25 -- this  unit  does not  by itself cause  the resulting  executable  to  be --
  26 -- covered  by the  GNU  General  Public  License.  This exception does not --
  27 -- however invalidate  any other reasons why  the executable file  might be --
  28 -- covered by the  GNU Public License.                                      --
  29 --                                                                          --
  30 -- GNAT is maintained by Ada Core Technologies Inc (http://www.gnat.com).   --
  31 --                                                                          --
  32 ------------------------------------------------------------------------------
  33
  34 --  Run-time non-symbolic traceback support
  35
  36 --  This package provides a method for generating a traceback of the
  37 --  current execution location. The traceback shows the locations of
  38 --  calls in the call chain, up to either the top or a designated
  39 --  number of levels.
  40
  41 --  The traceback information is in the form of absolute code locations.
  42 --  These code locations may be converted to corresponding source locations
  43 --  using the external addr2line utility, or from within GDB.
  44
  45 --  To analyze the code locations later using addr2line or gdb, the necessary
  46 --  units must be compiled with the debugging switch -g in the usual manner.
  47 --  Note that it is not necessary to compile with -g to use Call_Chain. In
  48 --  other words, the following sequence of steps can be used:
  49
  50 --     Compile without -g
  51 --     Run the program, and call Call_Chain
  52 --     Recompile with -g
  53 --     Use addr2line to interpret the absolute call locations
  54
  55 --  This capability is currently supported on the following targets:
  56
  57 --     All x86 ports
  58 --     AiX PowerPC
  59 --     HP-UX
  60 --     Irix
  61 --     Solaris sparc
  62 --     Tru64
  63 --     VxWorks PowerPC
  64 --     VxWorks Alpha
  65
  66 with System;
  67
  68 package GNAT.Traceback is
  69    pragma Elaborate_Body;
  70
  71    subtype Code_Loc is System.Address;
  72    --  Code location used in building tracebacks
  73
  74    type Tracebacks_Array is array (Positive range <>) of Code_Loc;
  75    --  Traceback array used to hold a generated traceback list.
  76
  77    ----------------
  78    -- Call_Chain --
  79    ----------------
  80
  81    procedure Call_Chain (Traceback : out Tracebacks_Array; Len : out Natural);
  82    --  Store up to Traceback'Length tracebacks corresponding to the current
  83    --  call chain. The first entry stored corresponds to the deepest level
  84    --  of subprogram calls. Len shows the number of traceback entries stored.
  85    --  It will be equal to Traceback'Length unless the entire traceback is
  86    --  shorter, in which case positions in Traceback past the Len position
  87    --  are undefined on return.
  88
  89 end GNAT.Traceback;