I have a system with Gigabyte GA-990XA-UD3 mobo, Phenom II X6 and Radeon HD 5750 graphics card, running Kubuntu 11.10, 3.1.2-030102-generic kernel and fglrx from the repositories (not the Catalyst drivers downloaded from ATI).

The system is not completely stable at the KDE level - the desktop crashes from time to time, and both chromium-browser and thunderbird crash frequently, with dmesg output like:

chromium-browser ......
chromium-browse[2565]: segfault at 68e88968 ip 00007f0463be2c08 sp 00007fff2dd58e50 error 4 in libX11.so.6.3.0[7f0463bad000+133000]

Thunderbird ......
Inconsistency detected by ld.so: ../sysdeps/x86_64/dl-machine.h: 466: elf_machine_rela_relative: Assertion `((reloc->r_info) & 0xffffffff) == 8' failed!

I'm not at a level that I understand what this means, but I suspect I have a shared object library problem. In that regard I note that this system has been upgraded over time from 10.04 to 11.04 to 11.10, and at one time it had the ATI Catalyst drivers, which I've hopefully completely removed, as they gave me much heartburn. That said, I've put some other outputs below - debug outputs from chromium-browser and thunderbird, a list of my environment variables, and lastly results of a search for libGL.so, indicating that those libraries are installed multiple times, and the instances are not the same. I suspect the same is true for other libraries.

So my question is ... what can I do to further diagnose and/or fix the problem.

Thanks, Gus

$ /usr/bin/chromium-browser -g
# Env:
# LD_LIBRARY_PATH=/usr/lib/chromium-browser
# PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games
# GTK_PATH=
# CHROMIUM_USER_FLAGS=
# CHROMIUM_FLAGS=
/usr/bin/gdb /usr/lib/chromium-browser/chromium-browser -x /tmp/chromiumargs.oEMMq4
GNU gdb (Ubuntu/Linaro 7.3-0ubuntu2) 7.3-2011.08
Copyright (C) 2011 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law. Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-linux-gnu".
For bug reporting instructions, please see:
<http://bugs.launchpad.net/gdb-linaro/>...
Reading symbols from /usr/lib/chromium-browser/chromium-browser...(no debugging symbols found)...done.
(gdb)

$ thunderbird -g
GNU gdb (Ubuntu/Linaro 7.3-0ubuntu2) 7.3-2011.08
Copyright (C) 2011 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law. Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-linux-gnu".
For bug reporting instructions, please see:
<http://bugs.launchpad.net/gdb-linaro/>...
Reading symbols from /usr/lib/thunderbird-8.0/thunderbird-bin...(no debugging symbols found)...done.
(gdb)

$ env
SSH_AGENT_PID=2081
KDE_MULTIHEAD=false
DM_CONTROL=/var/run/xdmctl
GPG_AGENT_INFO=/tmp/gpg-Eb3Y4f/S.gpg-agent:2083:1
SHELL=/bin/bash
TERM=xterm
XDG_SESSION_COOKIE=b700d48fe84f31c8072d1a280000001 2-1322595562.755999-1771921357
XDM_MANAGED=method=classic,auto
GTK2_RC_FILES=/etc/gtk-2.0/gtkrc:/home/rbroman/.gtkrc-2.0:/home/rbroman/.gtkrc-2.0-kde4:/home/rbroman/.kde/share/config/gtkrc-2.0
KONSOLE_DBUS_SERVICE=:1.132
GS_LIB=/home/rbroman/.fonts
GTK_RC_FILES=/etc/gtk/gtkrc:/home/rbroman/.gtkrc:/home/rbroman/.kde/share/config/gtkrc
WINDOWID=138412111
SHELL_SESSION_ID=73dae7da21b740009c52d073d1a328f1
GTK_MODULES=canberra-gtk-module:canberra-gtk-module
KDE_FULL_SESSION=true
.
LIBGL_DRIVERS_PATH=/usr/lib/fglrx/dri:/usr/lib32/fglrx/dri
SSH_AUTH_SOCK=/tmp/ssh-CFJyeUUo1981/agent.1981
SESSION_MANAGER=local/jboat17:@/tmp/.ICE-unix/2297,unix/jboat17:/tmp/.ICE-unix/2297
DEFAULTS_PATH=/usr/share/gconf/kde-plasma.default.path
XDG_CONFIG_DIRS=/etc/xdg/xdg-kde-plasma:/etc/xdg
DESKTOP_SESSION=kde-plasma
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games
PWD=/home/rbroman
KDE_SESSION_UID=1000
LANG=en_US.UTF-8
MANDATORY_PATH=/usr/share/gconf/kde-plasma.mandatory.path
QT_GRAPHICSSYSTEM=raster
UBUNTU_MENUPROXY=libappmenu.so
KONSOLE_DBUS_SESSION=/Sessions/2
HOME=/home/rbroman
COLORFGBG=15;0
SHLVL=1
KDE_SESSION_VERSION=4
LANGUAGE=
XCURSOR_THEME=default
LOGNAME=rbroman
XDG_DATA_DIRS=/usr/share/kde-plasma:/usr/local/share/:/usr/share/
DBUS_SESSION_BUS_ADDRESS=unix:abstract=/tmp/dbus-lbIalEBCBe,guid=df9eee4cc05cfa389e40444f00000026
LESSOPEN=| /usr/bin/lesspipe %s
WINDOWPATH=7
PROFILEHOME=
DISPLAY=:0
QT_PLUGIN_PATH=/home/rbroman/.kde/lib/kde4/plugins/:/usr/lib/kde4/plugins/
LESSCLOSE=/usr/bin/lesspipe %s %s
_=/usr/bin/env

$ sudo find / -name '*'libGL.so'*' | xargs ls -l
lrwxrwxrwx 1 root root 12 2011-11-27 10:50 /usr/lib32/fglrx/libGL.so.1 -> libGL.so.1.2
-rw-r--r-- 1 root root 865564 2011-10-26 22:45 /usr/lib32/fglrx/libGL.so.1.2
lrwxrwxrwx 1 root root 15 2011-10-07 15:30 /usr/lib32/libGL.so -> mesa/libGL.so.1
lrwxrwxrwx 1 root root 12 2011-10-07 15:30 /usr/lib32/mesa/libGL.so.1 -> libGL.so.1.2
-rw-r--r-- 1 root root 336248 2011-08-10 03:27 /usr/lib32/mesa/libGL.so.1.2
lrwxrwxrwx 1 root root 10 2011-10-26 22:45 /usr/lib/fglrx/libGL.so -> libGL.so.1
lrwxrwxrwx 1 root root 12 2011-10-26 22:45 /usr/lib/fglrx/libGL.so.1 -> libGL.so.1.2
-rw-r--r-- 1 root root 943704 2011-10-26 22:45 /usr/lib/fglrx/libGL.so.1.2
lrwxrwxrwx 1 root root 12 2011-08-10 03:27 /usr/lib/i386-linux-gnu/mesa/libGL.so.1 -> libGL.so.1.2
-rw-r--r-- 1 root root 336248 2011-08-10 03:27 /usr/lib/i386-linux-gnu/mesa/libGL.so.1.2
lrwxrwxrwx 1 root root 36 2011-11-27 07:54 /usr/lib/x86_64-linux-gnu/libGL.so -> /usr/lib/x86_64-linux-gnu/libGL.so.1
lrwxrwxrwx 1 root root 10 2011-08-10 03:20 /usr/lib/x86_64-linux-gnu/mesa/libGL.so -> libGL.so.1
lrwxrwxrwx 1 root root 12 2011-08-10 03:20 /usr/lib/x86_64-linux-gnu/mesa/libGL.so.1 -> libGL.so.1.2
-rw-r--r-- 1 root root 372400 2011-08-10 03:21 /usr/lib/x86_64-linux-gnu/mesa/libGL.so.1.2