Mesa 17.0 Git Lands OpenGL 4.5 Support For Intel Haswell
As of this afternoon in Mesa Git there is now OpenGL 4.5 support exposed by default for Haswell, joining the existing OpenGL 4.5 support for Broadwell and newer that has been present since Mesa 13.0. For those with older Ivy Bridge graphics, GL 3.3 is the current level while the GL 4.0 / FP64 work is still being vetted.
While Haswell HD/Iris Graphics isn't the fastest for Linux gaming, at least there's now OpenGL 4.5 support and it's a big stride from just the beginning of January when they were only at OpenGL 3.3 compliance.
This along with many other improvements will be in Mesa 17.0 that is set to debut in February. The feature freeze / branching for Mesa 17.0 is imminent as well for meeting that development schedule.
Those curious about current Intel Haswell performance numbers on Linux, I ran some tests a few weeks ago in Intel IvyBridge/Haswell/Broadwell/Skylake OpenGL & Vulkan Benchmarks On Linux 4.10 + Mesa 13.1.