1 ------------------------------------------------------------------------------
3 -- GNAT RUN-TIME COMPONENTS --
5 -- G N A T . T R A C E B A C K --
9 -- Copyright (C) 1999-2012, AdaCore --
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. --
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. --
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/>. --
27 -- GNAT was originally developed by the GNAT team at New York University. --
28 -- Extensive contributions were provided by Ada Core Technologies Inc. --
30 ------------------------------------------------------------------------------
32 -- Run-time non-symbolic traceback support
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
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.
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.
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:
53 -- Run the program, and call Call_Chain
55 -- Use addr2line to interpret the absolute call locations (note that
56 -- addr2line expects addresses in hexadecimal format).
58 -- This capability is currently supported on the following targets:
72 -- Note: see also GNAT.Traceback.Symbolic, a child unit in file g-trasym.ads
73 -- providing symbolic trace back capability for a subset of the above targets.
76 with Ada
.Exceptions
.Traceback
;
78 package GNAT
.Traceback
is
79 pragma Elaborate_Body
;
81 subtype Code_Loc
is System
.Address
;
82 -- Code location used in building tracebacks
84 subtype Tracebacks_Array
is Ada
.Exceptions
.Traceback
.Tracebacks_Array
;
85 -- Traceback array used to hold a generated traceback list
91 procedure Call_Chain
(Traceback
: out Tracebacks_Array
; Len
: out Natural);
92 -- Store up to Traceback'Length tracebacks corresponding to the current
93 -- call chain. The first entry stored corresponds to the deepest level
94 -- of subprogram calls. Len shows the number of traceback entries stored.
95 -- It will be equal to Traceback'Length unless the entire traceback is
96 -- shorter, in which case positions in Traceback past the Len position
97 -- are undefined on return.