Debugging GL apps

[Will Weisser <weisserw@rochester.rr.com>]

I seem to be having a serious problem...my OpenGL application does completely
different things under different drivers, and I have no way of debugging or
knowing why this is.  Basically what I have now is a small demo which gives you
a camera that can "walk" over terrain, which worked great under the old
NVidia/glx drivers (I have a TNT2).  Under the just released 3.3.5 drivers
however, my system locks up solid...I have no idea why.  And it gets even
weirder when I try software rendering...the software Mesa implementation (which
runs it at about 1fps) works fine as long as the ground is textured, but as
soon as I remove the texture it will segfault (in lambda_textured_triangle1
according to gdb).

So the problem is thus: I don't think I'm doing anything too spectacularly
fancy with OpenGL (most of my code is based on Steve Baker's ac_to_gl utility),
but I get entirely different responses from different drivers, and I have no
way of debugging any of them.  Even if I fix this, what happens when my code
gets released to the 100 other GL implementations out there which I don't even
have access to.  Any tips you guys could provide would be helpful.

 Thanks.

   -W.W.