Justin T. Gibbs
c5c33597bf
The COMPILER_RT_ASAN_ENABLE_EXCEPTIONS gate in asan/CMakeLists.txt
enables -fexceptions on the C++ slice (RTAsan_cxx /
RTAsan_dynamic_cxx — asan_new_delete.cpp) and tries to expose C++
standard headers to that TU (for forthcoming std::bad_alloc support)
by stripping -nostdinc++ from its cflags. The strip works for native
standalone builds but is wrong for cross builds: the host C++ headers
aren't valid for the target.
Split the C++-slice flag handling into two paths inside the existing
EXCEPTIONS gate:
* In-tree libc++ available (TARGET cxx-headers OR HAVE_LIBCXX):
keep -nostdinc++, append ${COMPILER_RT_CXX_CFLAGS} (a generator
expression that expands to "-isystem <prepared cxx-headers dir>"),
and add cxx-headers to DEPS so the header tree is staged before
the compile. Mirrors the pattern in orc / fuzzer / memprof /
tsan / xray.
* No in-tree libc++ (typical standalone build): drop -nostdinc++
for the C++ slice TU only so the host toolchain supplies C++ headers.
Reject COMPILER_RT_CXX_LIBRARY=none +
COMPILER_RT_ASAN_ENABLE_EXCEPTIONS=ON
at configure time: that combination opts out of any C++ stdlib while
asking for an exception-enabled C++ slice, silently leaking host headers
into a `none`-mode build.
Assisted by: Claude Opus 4.7
AddressSanitizer RT
================================
This directory contains sources of the AddressSanitizer (ASan) runtime library.
Directory structure:
README.txt : This file.
Makefile.mk : File for make-based build.
CMakeLists.txt : File for cmake-based build.
asan_*.{cc,h} : Sources of the asan runtime library.
scripts/* : Helper scripts.
tests/* : ASan unit tests.
Also ASan runtime needs the following libraries:
lib/interception/ : Machinery used to intercept function calls.
lib/sanitizer_common/ : Code shared between various sanitizers.
ASan runtime currently also embeds part of LeakSanitizer runtime for
leak detection (lib/lsan/lsan_common.{cc,h}).
ASan runtime can only be built by CMake. You can run ASan tests
from the root of your CMake build tree:
make check-asan
For more instructions see:
https://github.com/google/sanitizers/wiki/AddressSanitizerHowToBuild