Mesa 19.2.6 Released Due To POWER Fallout

Mesa 19.2.5 was just released earlier this week but now v19.2.6 has already been released due to the previous point release breaking IBM POWER builds.

Mesa 19.2.5 brought support on PowerPC 64-bit in LLVMpipe for using LLVM's large code model for JIT-compiled shaders since for large processes like GNOME Shell and Firefox there could be address space issues with the medium/small code models. Using that larger code model doesn't bring any measurable hit to the LLVMpipe performance but the commit introduced some problems when it was back-ported to the Mesa 19.2 series.

Mesa 19.2.5 ended up introducing a compile error on PPC64LE due to the change but that's now been addressed and warranted the immediate 19.2.6 release. Mesa does have continuous integration to try to avoid broken releases, but to date that is mostly focused on x86_64 (and to a growing but lesser extent, ARM). Most of Mesa's CI efforts are driven by Intel's robust hardware labs and resources.

Mesa 19.2.6 also picked up a few fixes to Broadcom V3D and a couple other mundane changes in the short time since Mesa 19.2.5. The list of Mesa 19.2.6 changes can be found via Mesa-dev.