Unable to debug Moonlight plugin in firefox

Question

On loading libmoonplugin.so I am getting following following error Unable to read JIT descriptor from remote memory!

Following is complete GDB session

GNU gdb (Ubuntu/Linaro 7.2-1ubuntu11) 7.2

Reading symbols from /usr/lib/firefox-4.0/firefox-bin...(no debugging symbols found)...done.

(gdb) symbol-file /usr/local/lib/moonlight/plugin/libmoonplugin.so

Reading symbols from /usr/local/lib/moonlight/plugin/libmoonplugin.so...done.

Unable to read JIT descriptor from remote memory!

(gdb) run ~/Desktop/default.html

Starting program: /usr/lib/firefox-4.0/firefox-bin ~/Desktop/default.html

Unable to read JIT descriptor from remote memory!

(gdb)

Answer 1

To debug firefox+moonlight the easiest is to start firefox, then attach gdb:

• Open firefox.
• Run this in a terminal to get the pid of the firefox process:

ps aux | grep firefox-bin

• Now start gdb, attaching to the firefox binary:

gdb program (pid)  
(lots of output from gdb)  
(gdb) continue

• Then in firefox just navigate to the web page you want to debug.