Linux: How to debug a SIGSEGV? How do I trace the error source?

Question

My firefox started crashing since today. I haven\'t changed anything on the system or on firefox config.

I use
strace -ff -o dumpfile.txt firefox

Answer 1

You can startup firefox in debug mode with this: firefox -d gdb

this will start firefox inside gdb.

You can the issue the gdb command 'run' and get a traceback when firefox crashes. This may be difficult, as firefox ships with stripped libraries which only shows which library and offset the code is in, not the function names.

Another alternative is to start firefox in safemode: firefox -safe-mode and turn off any plugins you may have installed until it doesn't crash anymore.

The last alternative is to enable the developer mode of firefox, and allow it to send the firefox crash session to the mozilla server. Then you can go the to mozilla site and see the detailed traceback of your failed firefox session.