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Date: Thu, 13 Jul 2006 17:40:00 -0000
From: Daniel Jacobowitz <drow@false.org>
To: Thomas Ackermann <tja@anykey.de>
Cc: gdb@sourceware.org
Subject: Re: Help with debugging LD_PRELOADed shared C libraries
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On Thu, Jul 13, 2006 at 07:38:06PM +0200, Thomas Ackermann wrote:
> It does not:
> 
> Cannot access memory at address 0x4001738c
> #0  0x400cc9b8 in ?? ()
> (gdb) info shared
> Cannot access memory at address 0x4001738c
> (gdb)
> 
> 
> Are you sure that this is true for a shared library that is loaded vias
> LD_PRELOAD? I mean, it is supposed to exchange functions from the binary
> - to which i have no source.

Absolutely sure.

It looks to me as if your kernel did not write out the _DYNAMIC segment
for some reason.  What does "readelf -l core" say?  How about "readelf
-l application"?

> > Are you sure that core dumps work on this system?
> 
> How to easy test this?
> I seem to remember using gdb on this system in earlier times already.

cat&
killall -ABRT <pid of cat>

Then try loading that core dump.

-- 
Daniel Jacobowitz
CodeSourcery