OpenSUSE Tumbleweed Eyeing LTO By Default; GCC 9 Optimization Work Thanks To Firefox

Longtime GCC developer Honza Hubička of SUSE has posted a lengthy and quite interesting blog post concerning some of the optimization work that went into the now-released GCC 9 compiler. It turns out some of the GCC 9 optimization work was motivated by the Firefox developers and their desire to switch to LLVM Clang in the name of performance. Separately, openSUSE Tumbleweed has been looking at using link-time optimizations (LTO) by default for their packages and that has also motivated developers and help ensured the LTO support was in good shape for this annual compiler release.

For those interested in compilers, Honza's post is a very interesting read and worth checking out this weekend. His favorite areas he had been working on for GCC 9 with inter-procedural analysis (IPA) and link-time optimizations (LTO) saw benefits this cycle. In regards to openSUSE Tumbleweed LTO'ing by default, only around 150 packages currently need LTO explicitly disabled for building. The size of the LTO'ed distribution has decreased by about 5% as a result, besides the possibility of performance gains on a per-package basis.

Those interested in GCC optimizations/performance are encouraged to check out Honza's blog post for the new GCC 9.1 compiler release.