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) 1999-2007, AdaCore                     --
  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,  51  Franklin  Street,  Fifth  Floor, --
  20 -- Boston, MA 02110-1301, 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 was originally developed  by the GNAT team at  New York University. --
  30 -- Extensive contributions were provided by Ada Core Technologies Inc.      --
  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 --  In order to use this facility, in some cases the binder must be invoked
  46 --  with -E switch (store the backtrace with exception occurrence). Please
  47 --  refer to gnatbind documentation for more information.
  48
  49 --  To analyze the code locations later using addr2line or gdb, the necessary
  50 --  units must be compiled with the debugging switch -g in the usual manner.
  51 --  Note that it is not necessary to compile with -g to use Call_Chain. In
  52 --  other words, the following sequence of steps can be used:
  53
  54 --     Compile without -g
  55 --     Run the program, and call Call_Chain
  56 --     Recompile with -g
  57 --     Use addr2line to interpret the absolute call locations (note that
  58 --      addr2line expects addresses in hexadecimal format).
  59
  60 --  This capability is currently supported on the following targets:
  61
  62 --     AiX PowerPC
  63 --     HP-UX
  64 --     GNU/Linux x86
  65 --     Irix MIPS
  66 --     LynxOS x86
  67 --     Solaris x86
  68 --     Solaris sparc
  69 --     Tru64 alpha
  70 --     OpenVMS/Alpha
  71 --     OpenVMS/ia64
  72 --     VxWorks PowerPC
  73 --     VxWorks x86
  74 --     Windows NT/XP
  75
  76 --  Note: see also GNAT.Traceback.Symbolic, a child unit in file g-trasym.ads
  77 --  providing symbolic trace back capability for a subset of the above targets.
  78
  79 with System;
  80 with Ada.Exceptions.Traceback;
  81
  82 package GNAT.Traceback is
  83    pragma Elaborate_Body;
  84
  85    subtype Code_Loc is System.Address;
  86    --  Code location used in building tracebacks
  87
  88    subtype Tracebacks_Array is Ada.Exceptions.Traceback.Tracebacks_Array;
  89    --  Traceback array used to hold a generated traceback list
  90
  91    ----------------
  92    -- Call_Chain --
  93    ----------------
  94
  95    procedure Call_Chain (Traceback : out Tracebacks_Array; Len : out Natural);
  96    --  Store up to Traceback'Length tracebacks corresponding to the current
  97    --  call chain. The first entry stored corresponds to the deepest level
  98    --  of subprogram calls. Len shows the number of traceback entries stored.
  99    --  It will be equal to Traceback'Length unless the entire traceback is
 100    --  shorter, in which case positions in Traceback past the Len position
 101    --  are undefined on return.
 102
 103 end GNAT.Traceback;