... at least as far as libGL is concerned, because they'd work just fine
if you tried. The only thing the ATI extension seems to add (I can't
find an official spec, this is inferred from the registry XML) is
selecting the GLX_RENDER_TYPE, which we don't validate before putting on
the wire. The only thing the NV extension adds is an additional fbconfig
attribute, and that only known by glXGetFBConfigAttrib; our
implementation of that just reads the value the server sends, if any,
and doesn't try to filter out unknown attributes.
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/10223>