As we mentioned yesterday when
X Server 1.5 RC4 was released (only to be outdone by
1.5 RC 5 that same day), this new version of the X Server (and therefore
X.Org 7.4) requires building against the latest Mesa code that ultimately will become known as Mesa 7.1. In addition to needing the latest-and-greatest from Mesa, a new version requirement for libdrm is also in place. The Direct Rendering Manager library is now at version 2.3.1 and that or a newer version (to come) will be needed for X Server 1.5 / X.Org 7.4. David Airlie's change-log for libdrm 2.3.1 just says "Stuff changed - you need this for Mesa 7.1, and Xorg 1.5 Deal with it." No
GEM or
TTM code is present in this DRM point-release. However, Intel will be rolling the
Graphics Execution Manager into libdrm 2.4 very shortly.
The (very brief) libdrm 2.3.1 release announcement can be read on
dri-devel.