[PyQt] Debugging memory corruption b/c of invalid GIL usage

[Kevin Watters]

I've got random sporadic crashes that look like memory corruption.  From
some googling around it looks similar to problems others have had when
they're not obtaining the GIL before calling Python code.

I've sifted through my .sip files looking for trouble spots with no
luck.

Is there some trick to drilling down where this would be happening in my
code? Some flag I can enable when building Python? (Building Python in
debug mode is a big undertaking, because then I have to rebuild all of
my extensions as well--maybe there's some #define I missed somewhere
that would fail fast if the GIL isn't obtained?)

Anyone have any experience in/suggestions for tracking down this kind of
bug in a Python extension?

Thanks,
Kevin