BTW: I hope gdb caught the exception in the output, since at the crash I got:

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0xa4fffb70 (LWP 4009)]

Looks like a crash in JS engine (JIT) - nanojit::LirBufWriter::ins0

Hm, I can't reproduce it with the same package...can you provide more precise steps how to reproduce it? Or try to run thunderbird inside gdb and attach the backtrace here. I'll attach instructions...

There are the steps there:
--------------------------

Please install thunderbird-debuginfo (debuginfo-install is from
yum-utils package).

 debuginfo-install thunderbird

Then run thunderbird with a parameter -g. That will start thunderbird running inside of gdb debugger. Then use command run and do whatever you did to make thunderbird crash. When it happens, you should go back to the gdb and run

 (gdb) thread apply all backtrace

This produces usually many screens of the text. Copy all of them into a text
editor and attach the file to the bug as an uncompressed attachment.

We will review this issue again once you've had a chance to attach this
information.

Thanks in advance.

Additionally, please try to run thunderbird inside valgrind (a debugging tool).

1) install valgrind
2) run "valgrind --trace-children=yes /usr/bin/thunderbird"

You may get some error messages before the crash so please attach them here.

Thanks for the bug report.  We have reviewed the information you have provided above, and there is some additional information we require that will be helpful in our diagnosis of this issue.

First of all, could we get output of the command

	rpm -qa *xulrun* *firefox* *mozilla* *flash* *plugin*

Please also install firefox-debuginfo (debuginfo-install is from
yum-utils package).

	debuginfo-install firefox

Then run firefox with a parameter -g. That will start firefox running inside of gdb debugger. Then use command run and do whatever you did to make firefox crash. When it happens, you should go back to the gdb and run

	(gdb) thread apply all backtrace

This produces usually many screens of the text. Copy all of them into a text editor and attach the file to the bug as an uncompressed attachment.

Please, install also valgrind (from valgrind package) and run

	valgrind --trace-children=yes --log-file=/tmp/firefox-valgrind-log.txt /usr/bin/firefox

(that's one line command, browser breaking this line into two notwithstanding)

Please, attach the file /tmp/firefox-valgrind-log.txt to this bug as an attachment as well.

We will review this issue again once you've had a chance to attach this information.

Thanks in advance.

sorry, the message got included by mistake ... it doesn't mean any additional requirements on your side aside from comment 4 and comment 5

(In reply to comment #4)
>  (gdb) thread apply all backtrace
> 
> This produces usually many screens of the text. Copy all of them into a text
> editor and attach the file to the bug as an uncompressed attachment.

See attachment in original comment #0.

(In reply to comment #5)
> Additionally, please try to run thunderbird inside valgrind (a debugging tool).

I assume you meant s/firefox/thunderbird/.

Upon start-up, I got:
$ valgrind --trace-children=yes --log-file=/tmp/thunderbird-valgrind-log.txt /usr/bin/thunderbird
Assertion 'pthread_mutex_unlock(&m->mutex) == 0' failed at pulsecore/mutex-posix.c:108, function pa_mutex_unlock(). Aborting.
/usr/lib/thunderbird-3.0b4/run-mozilla.sh: line 131:  2478 Killed                  "$prog" ${1+"$@"}

Since it did not get any further than just starting thunderbird (crashing as soon as the application fully started), I reran with --leak-check=full as well as suggested by valgrind's output.

Created attachment 366326 [details]
Output of valgrind as requested

Created attachment 366327 [details]
Output of valgrind rerun with --leak-check=full

You didn't run it with "--trace-children=yes" valgrind options so we get the debug info only from a loader. Please run the valgrind session again and add the --trace-children=yes command line argument.

Created attachment 369284 [details]
Output of valgrind rerun with --trace-children=yes --leak-check=full

*** Bug 558112 has been marked as a duplicate of this bug. ***

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