[andrzejl@wishmacer ~]$ gdb firefox
GNU gdb (GDB) 7.5.1
Copyright (C) 2012 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 "i686-pc-linux-gnu".
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>...
Reading symbols from /usr/bin/firefox...(no debugging symbols found)...done.
(gdb) run
Starting program: /usr/bin/firefox
warning: Could not load shared library symbols for linux-gate.so.1.
Do you need "set solib-search-path" or "set sysroot"?
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/usr/lib/libthread_db.so.1".
Traceback (most recent call last):
  File "/usr/share/gdb/auto-load/usr/lib/libgobject-2.0.so.0.3400.3-gdb.py", line 9, in <module>
    from gobject import register
  File "/usr/share/glib-2.0/gdb/gobject.py", line 3, in <module>
    import gdb.backtrace
ImportError: No module named backtrace
[New Thread 0xb25ffb40 (LWP 1902)]
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[Thread 0x9d6ffb40 (LWP 1921) exited]
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03:56:16 WARN firetray.Window window not visible, correcting visibility
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Program received signal SIGSEGV, Segmentation fault.
0xb6afc83f in ?? () from /usr/lib/firefox/libxul.so
(gdb) bt
#0  0xb6afc83f in ?? () from /usr/lib/firefox/libxul.so
#1  0xb6aff5d9 in ?? () from /usr/lib/firefox/libxul.so
#2  0xb6b1dc76 in ?? () from /usr/lib/firefox/libxul.so
#3  0xb6b1f9d7 in ?? () from /usr/lib/firefox/libxul.so
#4  0xb6b1fce0 in ?? () from /usr/lib/firefox/libxul.so
#5  0xb6ae47be in ?? () from /usr/lib/firefox/libxul.so
#6  0xb6b1fae4 in ?? () from /usr/lib/firefox/libxul.so
#7  0xb6b1f393 in ?? () from /usr/lib/firefox/libxul.so
#8  0xb6b1f9d7 in ?? () from /usr/lib/firefox/libxul.so
#9  0xb6b1fce0 in ?? () from /usr/lib/firefox/libxul.so
#10 0xb6ae47be in ?? () from /usr/lib/firefox/libxul.so
#11 0xb6b1fae4 in ?? () from /usr/lib/firefox/libxul.so
#12 0xb6b1f393 in ?? () from /usr/lib/firefox/libxul.so
#13 0xb6b1f9d7 in ?? () from /usr/lib/firefox/libxul.so
#14 0xb6b1fce0 in ?? () from /usr/lib/firefox/libxul.so
#15 0xb6ae47be in ?? () from /usr/lib/firefox/libxul.so
#16 0xb6b1fae4 in ?? () from /usr/lib/firefox/libxul.so
#17 0xb6b1f393 in ?? () from /usr/lib/firefox/libxul.so
#18 0xb6b1f9d7 in ?? () from /usr/lib/firefox/libxul.so
#19 0xb6b1fce0 in ?? () from /usr/lib/firefox/libxul.so
#20 0xb6b200b0 in ?? () from /usr/lib/firefox/libxul.so
#21 0xb6a8c609 in JS_CallFunctionValue(JSContext*, JSObject*, JS::Value, unsigned int, JS::Value*, JS::Value*) ()
   from /usr/lib/firefox/libxul.so
#22 0xb6263350 in ?? () from /usr/lib/firefox/libxul.so
#23 0xb625e87f in ?? () from /usr/lib/firefox/libxul.so
#24 0xb66d2a43 in ?? () from /usr/lib/firefox/libxul.so
#25 0xb5e9a51d in ?? () from /usr/lib/firefox/libxul.so
#26 0xb5e9a756 in ?? () from /usr/lib/firefox/libxul.so
#27 0xb5eaf982 in ?? () from /usr/lib/firefox/libxul.so
#28 0xb5eafdcb in ?? () from /usr/lib/firefox/libxul.so
#29 0xb5eb056a in ?? () from /usr/lib/firefox/libxul.so
#30 0xb5eb0834 in ?? () from /usr/lib/firefox/libxul.so
#31 0xb5e268d3 in js::BaseProxyHandler::regexp_toShared(JSContext*, JSObject*, js::RegExpGuard*) ()
   from /usr/lib/firefox/libxul.so
#32 0xb5dddab5 in ?? () from /usr/lib/firefox/libxul.so
#33 0xb5dddb0f in ?? () from /usr/lib/firefox/libxul.so
#34 0xb5e06841 in js::BaseProxyHandler::regexp_toShared(JSContext*, JSObject*, js::RegExpGuard*) ()
   from /usr/lib/firefox/libxul.so
#35 0xb5a7b5a1 in ?? () from /usr/lib/firefox/libxul.so
#36 0xb66bf144 in ?? () from /usr/lib/firefox/libxul.so
---Type <return> to continue, or q <return> to quit---
#37 0xb668f938 in ?? () from /usr/lib/firefox/libxul.so
#38 0xb6507b3e in ?? () from /usr/lib/firefox/libxul.so
#39 0xb66e1dc8 in ?? () from /usr/lib/firefox/libxul.so
#40 0xb66e1ef0 in ?? () from /usr/lib/firefox/libxul.so
#41 0xb6469af7 in ?? () from /usr/lib/firefox/libxul.so
#42 0xb632c062 in ?? () from /usr/lib/firefox/libxul.so
#43 0xb5a6ea06 in ?? () from /usr/lib/firefox/libxul.so
#44 0xb5a6ec52 in ?? () from /usr/lib/firefox/libxul.so
#45 0xb5a6ee7c in XRE_main () from /usr/lib/firefox/libxul.so
#46 0x0804a313 in _start ()