Comment # 22 on bug 57875 from Stefan Dösinger

Are you sure? I see nothing in the r300g git history that I'd expect to have
fixed this bug. Unless of course the hw does what ARB_depth_clamp requires when
you set CLIP_DISABLE and the rendering problems had nothing to do with
depth_clamp in the first place.

If the bug is indeed fixed a bisect for the commit fixing it might be
interesting.