gcc/ada/libgnat/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) 1999-2017, 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 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.                                     --
  17 --                                                                          --
  18 -- As a special exception under Section 7 of GPL version 3, you are granted --
  19 -- additional permissions described in the GCC Runtime Library Exception,   --
  20 -- version 3.1, as published by the Free Software Foundation.               --
  21 --                                                                          --
  22 -- You should have received a copy of the GNU General Public License and    --
  23 -- a copy of the GCC Runtime Library Exception along with this program;     --
  24 -- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    --
  25 -- <http://www.gnu.org/licenses/>.                                          --
  26 --                                                                          --
  27 -- GNAT was originally developed  by the GNAT team at  New York University. --
  28 -- Extensive contributions were provided by Ada Core Technologies Inc.      --
  29 --                                                                          --
  30 ------------------------------------------------------------------------------
  31
  32 --  Run-time non-symbolic traceback support
  33
  34 --  This package provides a method for generating a traceback of the
  35 --  current execution location. The traceback shows the locations of
  36 --  calls in the call chain, up to either the top or a designated
  37 --  number of levels.
  38
  39 --  The traceback information is in the form of absolute code locations.
  40 --  These code locations may be converted to corresponding source locations
  41 --  using the external addr2line utility, or from within GDB.
  42
  43 --  In order to use this facility, in some cases the binder must be invoked
  44 --  with -E switch (store the backtrace with exception occurrence). Please
  45 --  refer to gnatbind documentation for more information.
  46
  47 --  To analyze the code locations later using addr2line or gdb, the necessary
  48 --  units must be compiled with the debugging switch -g in the usual manner.
  49 --  Note that it is not necessary to compile with -g to use Call_Chain. In
  50 --  other words, the following sequence of steps can be used:
  51
  52 --     Compile without -g
  53 --     Run the program, and call Call_Chain
  54 --     Recompile with -g
  55 --     Use addr2line to interpret the absolute call locations (note that
  56 --      addr2line expects addresses in hexadecimal format).
  57
  58 --  This capability is currently supported on the following targets:
  59
  60 --     AiX PowerPC
  61 --     GNU/Linux x86
  62 --     GNU/Linux PowerPC
  63 --     LynxOS x86
  64 --     LynxOS 178 xcoff PowerPC
  65 --     LynxOS 178 elf PowerPC
  66 --     Solaris x86
  67 --     Solaris sparc
  68 --     VxWorks ARM
  69 --     VxWorks7 ARM
  70 --     VxWorks PowerPC
  71 --     VxWorks x86
  72 --     Windows XP
  73
  74 --  Note: see also GNAT.Traceback.Symbolic, a child unit in file g-trasym.ads
  75 --  providing symbolic trace back capability for a subset of the above targets.
  76
  77 with System;
  78 with Ada.Exceptions.Traceback;
  79
  80 package GNAT.Traceback is
  81    pragma Elaborate_Body;
  82
  83    subtype Code_Loc is System.Address;
  84    --  Code location used in building tracebacks
  85
  86    subtype Tracebacks_Array is Ada.Exceptions.Traceback.Tracebacks_Array;
  87    --  Traceback array used to hold a generated traceback list
  88
  89    ----------------
  90    -- Call_Chain --
  91    ----------------
  92
  93    procedure Call_Chain (Traceback : out Tracebacks_Array; Len : out Natural);
  94    --  Store up to Traceback'Length tracebacks corresponding to the current
  95    --  call chain. The first entry stored corresponds to the deepest level
  96    --  of subprogram calls. Len shows the number of traceback entries stored.
  97    --  It will be equal to Traceback'Length unless the entire traceback is
  98    --  shorter, in which case positions in Traceback past the Len position
  99    --  are undefined on return.
 100
 101 end GNAT.Traceback;