GCC 11 vs. LLVM Clang 12 Performance On The Intel Core i9 11900K Is A Heated Race

For those wondering how GCC and LLVM Clang are competing when running on Intel's latest Rocket Lake processors, here are some GCC 11 vs. LLVM Clang 12 compiler benchmarks with the Core i9 11900K running from the newly-released Fedora Workstation 34 featuring these very latest compilers. The compiler benchmarks were carried out at multiple optimization levels on each compiler.

As part of our ongoing benchmarks of GCC 11 vs. LLVM Clang 12 given these fresh open-source compiler releases, today's comparison is looking at the Core i9 11900K "Rocket Lake" performance. With both GCC and LLVM Clang, the benchmarks were carried out three times with varying CFLAGS/CXXFLAGS. Those flags included:

-O2 for the "standard" configuration often employed as a default.
"-O3 -march=native" for the more performant oriented build enjoyed by enthusiasts.
"-O3 -march=native -flto" for the optimized build while also enabling Link-Time Optimizations (LTO).

The same Intel Core i9 11900K system was obviously used throughout benchmarking with Fedora Workstation 34 and testing both GCC 11.1.1 and LLVM Clang 12.0.0 as offered through the F34 repository.