I'm a developer for the game Sauerbraten. Recently I noticed the following bugs in the OpenGL driver while developing for Win 7 Pro/OpenGL (as of Intel's 10/23/12 driver release) on i7/3720QM with an HD 4000 IGP:
1) Merely trying to compile a GLSL shader that uses the GL_ARB_texture_rectangle extension which calls the texture2DRectProj(sampler, vec4) function causes the GLSL compiler to crash. Calling the vec3 form, or the textureProj() form that exists in later GLSL versions does not seem to cause the GLSL compiler to crash.
Never in over 10 years of OpenGL development have I had a shader compiler crash on perfectly valid inputs. This deserves a prize of some sort in recognition of this achievement, I think. At least a bug report...
2) Using immediate mode (glBegin()/glEnd()) invalidates VBO/VA state, so that rendering any VBO/VAs that were bound before the immediate mode usage no longer works. This seems to be a nasty case of state leak in the implementation not properly restoring that after it uses it internally.
After lots of time spent on investigation, these bugs are definitely in Intel's driver. But, for the life of me, I can not find anywhere to submit OpenGL driver bug reports. I was told to try here. Is there somewhere? Or do I just have to put up with the bugs?