Re: problem with Gnat.Traceback.Symbolic on linux with Gnat 3.14p ?

["David C. Hoos" <david.c.hoos.sr@ada95.com>]

There is no problem with symbolic traceback on Linux with GNAT-3-14p,
in general.

There is, however, a small problem with some recent Linux distributions --
e.g., RedHat 7.2.

The problem is that there are two symbolic links
/usr/gnat/lib/gcc-lib/i686-pc-linux-gnu/2.8.1/rts-fsu/adalib/libbfd-2.9.5.0.
22.so
and
/usr/gnat/lib/gcc-lib/i686-pc-linux-gnu/2.8.1/rts-native/adalib/libbfd-2.9.5
.0.22.so

which link to /usr/lib/libbfd.so, which on RedHat 7.2 is a symbolic link to
libbfd-2.11.90.0.8.so

GNAT executables requiring symbolic traceback functionality that are built
with GNAT-3.14p will not work with  libbfd-2.11 -- they really require
libbfd-2.9, but the above chain of symbolic links causes the executable to
link to libbfd-2.11

Here are the steps I took to remedy the situation (for RedHat 7.2), doing
so in  such a way as to not disturb the environment for any executables
requiring libbfd-2.11:

1.  Copy libbfd-2.9.5.0.22 (e.g., from a RedHat 6.2 system) to
     /usr/gnat/lib/gcc-lib/i686-pc-linux-gnu/2.8.1/

2.  Delete the symbolic links

/usr/gnat/lib/gcc-lib/i686-pc-linux-gnu/2.8.1/rts-fsu/adalib/libbfd-2.9.5.0.
22.so
     and

/usr/gnat/lib/gcc-lib/i686-pc-linux-gnu/2.8.1/rts-native/adalib/libbfd-2.9.5
.0.22.so

3.  Replace those two links with links to ../../libbfd-2.9.5.0.22.so
     (This assumes you have already added
     /usr/gnat/lib/gcc-lib/i686-pc-linux-gnu/2.8.1/adalib to
/etc/ld.so.conf)

4.  Execute the command ldconfig

5.  In each main program source code file add the following pragma:
     pragma Linker_Options

("/usr/gnat/lib/gcc-lib/i686-pc-linux-gnu/2.8.1/libbfd-2.9.5.0.22.so");

6.  Compile with a command like the following:
     gnatmake -i -g <main-program-name> -bargs -E \
    -cargs -gnatwl -funwind-tables -O3 -Wuninitialized -fstack-check

For what it's worth, I also use florist, so I moved the floristlib directory
to /usr/gnat/lib after building it.

Here is a small test program that will verify that symbolic tracebacks work,
following these instructions:

with Ada.Text_IO;
with GNAT.Traceback.Symbolic;
procedure Test_Traceback
is
   pragma Linker_Options
     ("/usr/gnat/lib/gcc-lib/i686-pc-linux-gnu/2.8.1/libbfd-2.9.5.0.22.so");
   File : Ada.Text_IO.File_Type;
begin
   Ada.Text_IO.Open
     (File => File,
      Name => "abcdefghijklmnopqrstuvwxyz",
      Mode => Ada.Text_IO.In_File);
exception
   when E: others =>
      Ada.Text_IO.Put_Line
        (Ada.Exceptions.Exception_Information (E) & ASCII.LF &
         "Symbolic call stack traceback locations:" & ASCII.LF &
         GNAT.Traceback.Symbolic.Symbolic_Traceback (E));
end Test_Traceback;

I have been using gnat-3.14p since it became available on RedHat 6.2,
and 7.2, as well as Mandrake 7.1, with some very substantial programs
(one with 21 threads of execution) with excellent results.

David Hoos

----- Original Message -----
From: "nicolas" <n.brunot@cadwin.com>
Newsgroups: comp.lang.ada
To: <comp.lang.ada@ada.eu.org>
Sent: Thursday, March 28, 2002 5:17 AM
Subject: problem with Gnat.Traceback.Symbolic on linux with Gnat 3.14p ?


> Hello
> I have problems with Gnat.Traceback.Symbolic on Linux RedHAT 7.2 and Gnat
> 3.14p
>
> the command issued is
> gnatmake -f -funwind-tables -g test_trace.adb -bargs -E
>
> I get ?? instead of unit names and line numbers
>
> Note that everything works fine with the same command and Gnat 3.14p for
> Sparc
>
> Am I missing something obvious ? (other than Gnat 3.14p was not tested for
> RedHAT 7.2,  I know that ...)
>
> Thanks
>
>
>
>
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