Up until pretty recently I've been able to use debug breakpoints without problems in the nightly builds. However, recently any breakpoint I place is simply ignored by gdb, and I see the message "No source file named C:/dev/poke/pokepoke/gui.cpp." in the debug log. Obviously this file exists, because I'm editing it when this message appears, but it happens with any source file that I try to debug (in the project I'm working on, at least. I haven't tried others yet).