I made a change recently on the gjay program. gjay is a gtk program that basically analyzes your music and makes playlists. There is a gui frontend and a analyzer back-end and they communicate through a pipe.
One really useful debugging option gtk has is to make warnings fatal, so when gtk finds one it crashes at that point and you can use gdb to trap it. The flag is –g-fatal-warnings. I have been updating gjay and initially it didn’t have this option, so I needed to add the gtk options, which is a simple one-liner.