Bug#924448: gimp: Bug#924448: segfault when using measuring tool

[Bernhard Übelacker]

Hello Kingsley G. Morse Jr.,


> My main concern?>> The normal way of eliciting a back trace from> within gdb didn't work.> > The non repeating lines were reported by defining> a function in gdb and logging output to a file.

You can start gimp that way to get a backtrace:

    script -c "gdb -q -ex 'set width 0' -ex 'set pagination off' -ex 'run' -ex 'bt' -ex 'detach' -ex 'quit' --args gimp" -a gdb_gimp_$(date +%Y-%m-%d_%H-%M-%S).log

This gave me a 11MB file, so it took some time
for gdb to finish to write the 68000 stack frames.

Another alternative is to install a coredump collector
like systemd-coredump. After that you should be able to
list collected core dumps of the current boot by:

    coredumpctl list

And have that core dump loaded into gdb by:

    coredumpctl gdb <PID>

Both may lead to better results if you have debug
symbols installed like described in [1].
In this case packages gimp-dbgsym libglib2.0-0-dbgsym.

For debugging graphical applications it may also be convenient
to ssh into the target machine if a second computer is available,
or at least start gdb from the "ctl-alt-F1 old school console".

This can be combined with running gdb inside tmux in the graphical
environment and, if keyboard gets locked, ctl-alt-F1 and 'tmux attach'
to access the locked gdb. And if the tmux step was missed, it may be
possible to "move" the locked gdb process to another terminal ...

Happy debugging. :-)

Kind regards,
Bernhard

[1] https://wiki.debian.org/HowToGetABacktrace#Installing_the_debugging_symbols