https://bugs.freedesktop.org/show_bug.cgi?id=69341

--- Comment #14 from Michel Dänzer michel@daenzer.net --- (In reply to comment #11)

The root of the problem *isn't* glamor: I just tried Glamor with Intel HD4000 and it works flawlessly. The issue is with mesa.

Could also be the glamor glue code in xf86-video-ati.