llvm-project

8b459943 - [asan] Enable exceptions for asan_new_delete.cpp translation unit (#200719)

[asan] Enable exceptions for asan_new_delete.cpp translation unit (#200719) Groundwork for #196388. Preparation for a follow-up change that lets the throwing operator new wrappers in asan_new_delete.cpp throw std::bad_alloc on OOM. To support that, asan_new_delete.cpp must be compiled with -fexceptions and must be able to include <new> (i.e. without -nostdinc++). The rest of the ASan runtime stays compiled with -fno-exceptions and -nostdinc++. NOTE: Comments in CMakeLists.txt are written assuming the follow-on changes to use exceptions land, thus avoiding the need to update this file again. Build-system changes: * Define ASAN_CXX_CFLAGS as ASAN_CFLAGS minus -fno-exceptions and -nostdinc++ plus -fexceptions. Define ASAN_DYNAMIC_CXX_CFLAGS likewise relative to ASAN_DYNAMIC_CFLAGS. RTTI stays disabled; libstdc++ / libc++abi supply the bad_alloc typeinfo. * Static build: switch RTAsan_cxx (which already contains only ${ASAN_CXX_SOURCES} = asan_new_delete.cpp) from ASAN_CFLAGS to ASAN_CXX_CFLAGS. RTAsan (the C slice) is unchanged. * Dynamic build: split the previous single RTAsan_dynamic object library into two — RTAsan_dynamic keeps ${ASAN_SOURCES} (no change in flags) and a new RTAsan_dynamic_cxx carries ${ASAN_CXX_SOURCES} with ASAN_DYNAMIC_CXX_CFLAGS. Both shared clang_rt.asan link rules pull in RTAsan_dynamic_cxx alongside RTAsan_dynamic so the linked .so retains the same set of object files; only the compile flags for asan_new_delete.cpp change. NFC at runtime — the asan_new_delete.cpp source as of this commit does not yet use exceptions or include <new>, so the new flags are inert. The follow-up commit makes use of them. Assisted by: Claude Opus 4.7