llvm-project

46de3200 - [compiler-rt][rtsan] Fix build failures when building against in-tree libc++ (#175638)

[compiler-rt][rtsan] Fix build failures when building against in-tree libc++ (#175638) When building compiler-rt against an in-tree libc++, intermittent build failures could occur: some rtsan sources referenced c++ stdlib includes (i.e. `#include <new>`), but there was no CMake dependency enforcing that the libc++ headers were copied into place before the rtsan sources were built. https://github.com/llvm/llvm-project/issues/127764#issue-2862550745 proposed adding the dependency on the `cxx-headers` target to resolve the issue. But my understanding is that compiler-rt sanitizer runtimes aren't expected to bring in C++ stdlib includes in the first place -- `SANITIZER_COMMON_CFLAGS`, used by the other sanitizer runtimes, contains `-nostdinc++`. Rtsan only included `<new>` to get support for placement new. `sanitizer_common/sanitizer_placement_new.h` can provide this without the need for C++ stdlib headers. Move from `COMPILER_RT_COMMON_CFLAGS`/`COMPILER_RT_CXX_CFLAGS` to `SANITIZER_COMMON_CFLAGS`, and from `COMPILER_RT_COMMON_LINK_FLAGS` to `SANITIZER_COMMON_LINK_FLAGS` to be consistent with the other sanitizers. Fixes #127764.