Mesa out of date (and move to libglvnd?)

[John Kehayias <john.kehayias@protonmail.com>]

Hi everyone,

Mesa has fallen quite of date (latest upstream is 21.1.4, guix core-updates up to 20.2.6, or else 20.2.4 for everyone else). There is patch available here: https://issues.guix.gnu.org/49339 however it currently includes enabling libglvnd. I don't think that is necessary from my testing, but does raise the question of moving to libglvnd for packages requiring GL (which would be needed if Mesa has it enabled).

As far as I understand it, libglvnd is meant to be vendor neutral and provide GL for anything to link to, and then hands off to vendor specific GL. I have at tested building some packages when mesa has libglvnd enabled, like libepoxy and xorg-server. Both needed libglvnd as inputs, but otherwise build fine. I haven't tested running as I'm currently on a foreign distro. However, does seem like this would be a good idea, as it should alleviate dealing with vendor specific GL in building packages. libglvnd is new to me, but perhaps someone can weigh in on this issue?

Anyway, my main goal right now is to have Mesa updated in core-updates before the upcoming freeze. Mesa is already very out of date, and would then push it to another ~6 months for the next core-updates when it is already ~7 months out of date (and they make quick releases for fixes in drivers and software that uses Mesa).

I can update #49339 with a minimal Mesa version bump patch if that helps, just don't want it to get lost in the current shuffle.

Thanks!
John