Debugging Fennec can be trickier than Firefox because it uses multiple processes.
For example to debug reftests in fennec on desktop linux the following recipe works:
python runreftest.py --debugger=gdb TEST_PATH/reftest.list
once inside gdb
- this will break on fork calls
(gdb) catch fork
- this will break on exec calls
(gdb) catch exec
(gdb) run
- the first fork will be for glx probing and can be ignor
(gdb) continue
- the next fork is the content process, make sure we follow into it
(gdb) set follow-fork-mode child (gdb) continue
- this will break on the exec
(gdb) break some_function_in_the content process
sdqwd