[Mesa-dev] Intent to retire ancient driver support

[Adam Jackson]

Sending this on to the list for visibility, since not everyone follows
everything on gitlab. In this merge request:

https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7660

I retire support for DRI drivers older than Mesa 8.0, which was
February 2012. In particular this retires the ability for libGL to
even load DRI1 drivers, which last existed in Mesa 7.11. We are not
aware of any currently supported distros trying to ship both DRI1
drivers and anything newer. In fact the only distro I'm aware of that
ever _tried_ was RHEL 6, which goes into extended-life support at the
end of the month, and which is currently shipping Mesa 11.0.7 and is
thus _way_ behind the times in terms of hardware enablement.

Eric Anholt suggested that glvnd is the better way to retain DRI1
support at this point, and to that end there is also:

https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7674

Which allows us to override the glvnd vendor name. xserver could then
select a different name for DRI1 screens, and now you get
parallel-installable Mesa packages, which could be nice for a bunch of
reasons.

If you still care about DRI1 support, I am very sorry, but hopefully
!7674 (backported to 20.x) and a bit of polish to xserver should keep
things working for you, and your feedback/testing would be greatly
appreciated.

- ajax