llvm-project

ac45132c - Reapply "[ASan][Fuchsia] Have Fuchsia use a dynamic shadow start" (#182972) (#183154)

Reapply "[ASan][Fuchsia] Have Fuchsia use a dynamic shadow start" (#182972) (#183154) This reverts commit 19daed352f218f866ebcbbf3f35b14918588d8a1 but keeping the original cmake in compiler-rt/lib/asan/CMakeLists.txt as is. Prior we were attempting to use clang-cl for building ASM with all the normal flags but extra flags are needed to force clang-cl to be used as an assembler. For now, it's just easier to not touch any of the cmake machinery and omit building the assembly for windows builds, but we still keep the `#if` in the asm file to avoid having a fuchsia-specific exclusion.