• Fix miscompilation in produced Windows MSVC artifacts This was introduced by enabling ThinLTO for the distributed rustc which led to miscompilations in the resulting binary. Currently this is believed to be limited to the -Zdylib-lto flag used for rustc compilation, rather than a general bug in ThinLTO, so only rustc artifacts should be affected.
• Fix --enable-local-rust builds
• Treat $prefix-clang as clang in linker detection code
• Fix panic in compiler code