problem with multithreaded application and Xlib

[Nix]

On 30 Sep 2010, Francesco Abbate uttered the following:
> Or may be I've just to switch back to the stable version of X Window
> and wait for this bug to be fixed for the next release. The problem is
> that I needs to have at least OpenGL 2 to use shaders and the binary
> ATI driver does not works (sic!). The development with the Gallium
> architecture is very interesting and exciting but for the moment it is
> just not ready :-)

Upgrade Mesa to 7.9-to-be (requires xorg-xserver 1.9) and you should
find that shaders work perfectly well with xf86-video-ati. They do for
me, anyway. (This is a recent change, so may be unstable, although I've
seen no problems.)