During my work on Epiphany I was debugging a problem with the “woohoo” bar. It took me not less than three days to understand the issue, write a test case, and a patch and put everything in this bug. Matthias Clasen was kind enough to review and commit the patch and it can be found here. Sadly the –author tag of git was not used and the commit does not carry my name, so ohloh will not list my contribution to Gtk+.

The main issue with debugging was finding signal connections, e.g. which function is connected to that signal and which objects, and figuring out what was called during the signal activation. My approach was the usual printf method in many places and adding _backtrace() to function calls using the glibc builtin backtracing functionality. I would like to have SystemTap at a state I could use it for tracing, or be able to script gdb (it has python plugin support now) to automatically execute a trigger when certain parts of the code got executed.

Anyway, I’m happy to have fixed a Gtk+ bug and being a contributor now.