One of the interesting milestones this year in the compiler world was the ability with LLVM Clang 9.0 to compile Linux 5.3+ for x86_64 without needing any extra patches to either the kernel or the LLVM/Clang compiler. That initial support in Linux 5.3 was not without a few issues, but on Linux 5.5 the experience is in great shape with the stable Clang compiler.

Source: Phoronix – Ringing In 2020 By Clang’ing The Linux 5.5 Kernel – Benchmarks Of GCC vs. Clang Built Kernels