Several *BSD projects have been using the Clang toolchain by default for many years, and have been a massive driving force in getting these fixes upstreamed so

Several *BSD projects have been using the Clang toolchain by default for many years, and have been a massive driving force in getting these fixes upstreamed so that other systems, incl. Linux distributions can benefit from greater choice of compilers. FreeBSD since 10.x on i386/amd64, not sure about the status on other platforms. OpenBSD since 6.1 for arm64, 6.2 for i386/amd64. This is both default for the base system, meaning kernel and userland. And also the ports tree, for compiling 3rd party packages, very few ports still depend on gcc. And also, while not the default system compiler yet, LLVM/clang is compiled and installed on macppc/sparc64 and mips64 systems.