GCC 7.3 Released With Spectre V2 Mitigation Support

GNU Compiler Collection 7.3 is now available as the latest GCC7 point release and the prominent changes being support for helping mitigate Spectre variant two using some new compiler switches.

GCC 7.3 has backported Retpoline support after GCC 8.0 development code initially received the support earlier this month. This GCC support building out a patched kernel can lead to "full" retpoline protection for the system.

The Retpoline support adds a few new compiler switches, namely -mindirect-branch= for dealing with indirect branches to avoid speculative execution.

Besides the Spectre v2 patches, GCC 7.3 has around 100 other bug fixes over GCC 7.2.0. The Spectre patches are still expected to be back-ported to older versions of GCC.

While there were around 100 bug fixes in GCC 7.3, the GCC 7.4 cycle is starting off with still around around 164 P2 bugs and 22 P3 bugs (as well as plenty of P4 and P5 bugs of lesser priority). The brief GCC 7.3 release announcement can be read on the mailing list.

Meanwhile, a few days back LLVM landed its Retpoline support and that should appear soon in a back-ported LLVM Clang 5.0 release.