Intel MIC Offloading For Xeon Phi Dropped With GCC 13 Compiler

On the same day as new GCC compiler patches for next-generation processors coming out for those wares that are more than one year out, the GNU Compiler Collection dropped a remnant from Intel's past: the Many Integrated Core "MIC" architecture support with Xeon Phi for offloading.

Going back nearly a decade was GCC 5 with Intel MIC offloading by way of OpenMP and OpenACC APIs. Intel worked out the support for offloading work to the Intel MIC / Xeon Phi hardware and the compiler support has been present since in GCC.

But as most Phoronix readers know, Xeon Phi has been discontinued for years. Intel sold off their remaining inventory very cheap and since then the software support has been left to bit rot. Back in 2020 with the Linux 5.10 kernel, the Intel MIC support was removed with it being unmaintained and Intel not pursuing their MIC architecture.

So unless you stick to an older kernel the Xeon Phi / MIC support has already been not working on Linux and now with the GCC 13 compiler that compiler-side support has been removed.

Thomas Schwinge of CodeSourcery removed the Intel MIC offloading support from GCC. Getting rid off the GCC support and liboffloadmic library lightens the codebase by 75,949 lines of code.

The removal happened and is set for GCC 13 along with support for many new Intel CPUs, new x86_64 ISA extensions, and a ton of other compiler improvements. GCC 13.1 stable will be out in the early months of 2023.