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 --           Copyright (C) 1999-2001 Ada Core Technologies, 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 2,  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 COPYING.  If not, write --
  19 -- to  the Free Software Foundation,  59 Temple Place - Suite 330,  Boston, --
  20 -- MA 02111-1307, USA.                                                      --
  21 --                                                                          --
  22 -- As a special exception,  if other files  instantiate  generics from this --
  23 -- unit, or you link  this unit with other files  to produce an executable, --
  24 -- this  unit  does not  by itself cause  the resulting  executable  to  be --
  25 -- covered  by the  GNU  General  Public  License.  This exception does not --
  26 -- however invalidate  any other reasons why  the executable file  might be --
  27 -- covered by the  GNU Public License.                                      --
  28 --                                                                          --
  29 -- GNAT is maintained by Ada Core Technologies Inc (http://www.gnat.com).   --
  30 --                                                                          --
  31 ------------------------------------------------------------------------------
  32
  33 --  Run-time non-symbolic traceback support
  34
  35 --  This package provides a method for generating a traceback of the
  36 --  current execution location. The traceback shows the locations of
  37 --  calls in the call chain, up to either the top or a designated
  38 --  number of levels.
  39
  40 --  The traceback information is in the form of absolute code locations.
  41 --  These code locations may be converted to corresponding source locations
  42 --  using the external addr2line utility, or from within GDB.
  43
  44 --  To analyze the code locations later using addr2line or gdb, the necessary
  45 --  units must be compiled with the debugging switch -g in the usual manner.
  46 --  Note that it is not necessary to compile with -g to use Call_Chain. In
  47 --  other words, the following sequence of steps can be used:
  48
  49 --     Compile without -g
  50 --     Run the program, and call Call_Chain
  51 --     Recompile with -g
  52 --     Use addr2line to interpret the absolute call locations
  53
  54 --  This capability is currently supported on the following targets:
  55
  56 --     All x86 ports
  57 --     AiX PowerPC
  58 --     HP-UX
  59 --     Irix
  60 --     Solaris sparc
  61 --     Tru64
  62 --     VxWorks PowerPC
  63 --     VxWorks Alpha
  64
  65 with System;
  66
  67 package GNAT.Traceback is
  68    pragma Elaborate_Body;
  69
  70    subtype Code_Loc is System.Address;
  71    --  Code location used in building tracebacks
  72
  73    type Tracebacks_Array is array (Positive range <>) of Code_Loc;
  74    --  Traceback array used to hold a generated traceback list.
  75
  76    ----------------
  77    -- Call_Chain --
  78    ----------------
  79
  80    procedure Call_Chain (Traceback : out Tracebacks_Array; Len : out Natural);
  81    --  Store up to Traceback'Length tracebacks corresponding to the current
  82    --  call chain. The first entry stored corresponds to the deepest level
  83    --  of subprogram calls. Len shows the number of traceback entries stored.
  84    --  It will be equal to Traceback'Length unless the entire traceback is
  85    --  shorter, in which case positions in Traceback past the Len position
  86    --  are undefined on return.
  87
  88 end GNAT.Traceback;