This has been wrong for many years. It was originally 0x000FFFFF and long
ago there was discussion about whether GL_ALL_ATTRIB_BITS should include
the then-new GL_MULTISAMPLE_BIT bit. Eventually the ARB decided that
glPushAttrib(GL_ALL_ATTRIB_BITS) should save all current and future
attribute groups (hence ~0). Unfortunately, Mesa's gl.h was never updated.
This was just recently spotted by Eric Anholt and reported as a bug to the
ARB. Ian, Jon Leech and I discussed it at the ARB meeting and decided to
change Mesa's value to reflect the ARB's decision.
Acked-by: Eric Anholt <eric@anholt.net>
349b76a553