[compiler-rt][CMake] Set --unwindlib=none when using LLVM libunwind

[phosek]

Summary

We already link libunwind explicitly so avoid trying to link toolchain's
default libunwind which may be missing. This matches what we already do
for libcxx and libcxxabi.

compiler-rt/CMakeLists.txt

 string(APPEND COMPILER_RT_TEST_COMPILER_CFLAGS " ${stdlib_flag}")
 
 # When cross-compiling, COMPILER_RT_TEST_COMPILER_CFLAGS help in compilation
 # and linking of unittests.
 string(REPLACE " " ";" COMPILER_RT_UNITTEST_CFLAGS "${COMPILER_RT_TEST_COMPILER_CFLAGS}")
 set(COMPILER_RT_UNITTEST_LINK_FLAGS ${COMPILER_RT_UNITTEST_CFLAGS})
 
 if(COMPILER_RT_USE_LLVM_UNWINDER)
+  append_list_if(CXX_SUPPORTS_UNWINDLIB_NONE_FLAG --unwindlib=none COMPILER_RT_COMMON_LINK_FLAGS)
+  append_list_if(CXX_SUPPORTS_UNWINDLIB_NONE_FLAG --unwindlib=none COMPILER_RT_UNITTEST_LINK_FLAGS)
   if (COMPILER_RT_ENABLE_STATIC_UNWINDER)
     set(unwinder_target unwind_static)
   else()
     set(unwinder_target unwind_shared)
   endif()
-  list(APPEND SANITIZER_CXX_ABI_LIBRARIES "$<$<TARGET_EXISTS:${unwinder_target}>:$<TARGET_LINKER_FILE:${unwinder_target}>>")
+  list(APPEND COMPILER_RT_UNWINDER_LINK_LIBS "$<$<TARGET_EXISTS:${unwinder_target}>:$<TARGET_LINKER_FILE:${unwinder_target}>>")
 endif()
 
 if (COMPILER_RT_CXX_LIBRARY STREQUAL "libcxx")
   # We are using the in-tree libc++ so avoid including the default one.
   append_list_if(COMPILER_RT_HAS_NOSTDINCXX_FLAG -nostdinc++ COMPILER_RT_COMMON_CFLAGS)
   append_list_if(COMPILER_RT_HAS_NOSTDLIBXX_FLAG -nostdlib++ COMPILER_RT_COMMON_LINK_FLAGS)
   # Use the in-tree libc++ through explicit include and library paths.
   if (COMPILER_RT_STATIC_CXX_LIBRARY)
     set(cxx_target cxx_static)
   else()
     set(cxx_target cxx_shared)
   endif()
   list(APPEND COMPILER_RT_CXX_CFLAGS "$<$<TARGET_EXISTS:cxx-headers>:-isystem$<JOIN:$<TARGET_PROPERTY:cxx-headers,INTERFACE_INCLUDE_DIRECTORIES>,$<SEMICOLON>-isystem>>")
   list(APPEND COMPILER_RT_CXX_LINK_LIBS "$<$<TARGET_EXISTS:${cxx_target}>:$<TARGET_LINKER_FILE:${cxx_target}>>")
 elseif (COMPILER_RT_CXX_LIBRARY STREQUAL "none")
   # We aren't using any C++ standard library so avoid including the default one.
   append_list_if(COMPILER_RT_HAS_NOSTDINCXX_FLAG -nostdinc++ COMPILER_RT_COMMON_CFLAGS)
   append_list_if(COMPILER_RT_HAS_NOSTDLIBXX_FLAG -nostdlib++ COMPILER_RT_COMMON_LINK_FLAGS)
 else()
   # Nothing to be done for `default`.
 endif()
 
 macro(append_libcxx_libs var)
   if (${var}_INTREE)
+    # TODO: the unwinder selection should only be controlled by COMPILER_RT_USE_LLVM_UNWINDER.
+    append_list_if(CXX_SUPPORTS_UNWINDLIB_NONE_FLAG --unwindlib=none SANITIZER_COMMON_LINK_FLAGS)
+
     if (SANITIZER_USE_STATIC_LLVM_UNWINDER AND (TARGET unwind_static OR HAVE_LIBUNWIND))
       list(APPEND ${var}_LIBRARIES unwind_static)
     elseif (TARGET unwind_shared OR HAVE_LIBUNWIND)
       list(APPEND ${var}_LIBRARIES unwind_shared)
     endif()
 
     if (SANITIZER_USE_STATIC_CXX_ABI AND (TARGET cxxabi_static OR HAVE_LIBCXXABI))
       list(APPEND ${var}_LIBRARIES cxxabi_static)

compiler-rt/lib/asan/tests/CMakeLists.txt

set(ASAN_UNITTEST_COMMON_CFLAGS
   -Wno-format
   -Werror=sign-compare)
 append_list_if(COMPILER_RT_HAS_WVARIADIC_MACROS_FLAG -Wno-variadic-macros ASAN_UNITTEST_COMMON_CFLAGS)
 
 # This will ensure the target linker is used
 # during cross compilation
 set(ASAN_UNITTEST_COMMON_LINK_FLAGS
   ${COMPILER_RT_UNITTEST_LINK_FLAGS}
+  ${COMPILER_RT_UNWINDER_LINK_LIBS}
   ${SANITIZER_TEST_CXX_LIBRARIES})
 
 # -gline-tables-only must be enough for ASan, so use it if possible.
 if(COMPILER_RT_TEST_COMPILER_ID MATCHES "Clang")
   list(APPEND ASAN_UNITTEST_COMMON_CFLAGS -gline-tables-only)
 else()
   list(APPEND ASAN_UNITTEST_COMMON_CFLAGS -g)
 endif()

compiler-rt/lib/gwp_asan/tests/CMakeLists.txt

set(GWP_ASAN_UNIT_TEST_HEADERS
   ${GWP_ASAN_HEADERS}
   harness.h)
 
 add_custom_target(GwpAsanUnitTests)
 set_target_properties(GwpAsanUnitTests PROPERTIES FOLDER "Compiler-RT Tests")
 
 set(GWP_ASAN_UNITTEST_LINK_FLAGS
   ${COMPILER_RT_UNITTEST_LINK_FLAGS} -ldl
+  ${COMPILER_RT_UNWINDER_LINK_LIBS}
   ${SANITIZER_TEST_CXX_LIBRARIES})
 list(APPEND GWP_ASAN_UNITTEST_LINK_FLAGS --driver-mode=g++)
 if(NOT WIN32)
   list(APPEND GWP_ASAN_UNITTEST_LINK_FLAGS -pthread)
 endif()
 
 if(COMPILER_RT_DEFAULT_TARGET_ARCH IN_LIST GWP_ASAN_SUPPORTED_ARCH)
   # GWP-ASan unit tests are only run on the host machine.

compiler-rt/lib/interception/tests/CMakeLists.txt

set(INTERCEPTION_TEST_CFLAGS_COMMON
   -I${COMPILER_RT_SOURCE_DIR}/lib
   -I${COMPILER_RT_SOURCE_DIR}/lib/interception
   -fno-rtti
   -O2
   -Werror=sign-compare)
 
 set(INTERCEPTION_TEST_LINK_FLAGS_COMMON
   ${COMPILER_RT_UNITTEST_LINK_FLAGS}
+  ${COMPILER_RT_UNWINDER_LINK_LIBS}
   ${SANITIZER_TEST_CXX_LIBRARIES})
 
 # -gline-tables-only must be enough for these tests, so use it if possible.
 if(COMPILER_RT_TEST_COMPILER_ID MATCHES "Clang")
   list(APPEND INTERCEPTION_TEST_CFLAGS_COMMON -gline-tables-only)
 else()
   list(APPEND INTERCEPTION_TEST_CFLAGS_COMMON -g)
 endif()

compiler-rt/lib/memprof/tests/CMakeLists.txt

 
 set(MEMPROF_UNITTEST_LINK_FLAGS
   ${COMPILER_RT_UNITTEST_LINK_FLAGS})
 
 if(NOT WIN32)
   list(APPEND MEMPROF_UNITTEST_LINK_FLAGS -pthread)
 endif()
 
-set(MEMPROF_UNITTEST_LINK_LIBRARIES ${SANITIZER_TEST_CXX_LIBRARIES})
+set(MEMPROF_UNITTEST_LINK_LIBRARIES
+  ${COMPILER_RT_UNWINDER_LINK_LIBS}
+  ${SANITIZER_TEST_CXX_LIBRARIES})
 list(APPEND MEMPROF_UNITTEST_LINK_LIBRARIES "dl")
 
 if(COMPILER_RT_DEFAULT_TARGET_ARCH IN_LIST MEMPROF_SUPPORTED_ARCH)
   # MemProf unit tests are only run on the host machine.
   set(arch ${COMPILER_RT_DEFAULT_TARGET_ARCH})
 
   add_executable(MemProfUnitTests 
     ${MEMPROF_UNITTESTS}

compiler-rt/lib/sanitizer_common/tests/CMakeLists.txt

set(SANITIZER_TEST_CFLAGS_COMMON
   -fno-rtti
   -O2
   -Werror=sign-compare
   -Wno-gnu-zero-variadic-macro-arguments
   )
 
 set(SANITIZER_TEST_LINK_FLAGS_COMMON
   ${COMPILER_RT_UNITTEST_LINK_FLAGS}
+  ${COMPILER_RT_UNWINDER_LINK_LIBS}
   ${SANITIZER_TEST_CXX_LIBRARIES})
 
 # -gline-tables-only must be enough for these tests, so use it if possible.
 if(COMPILER_RT_TEST_COMPILER_ID MATCHES "Clang")
   list(APPEND SANITIZER_TEST_CFLAGS_COMMON -gline-tables-only)
 else()
   list(APPEND SANITIZER_TEST_CFLAGS_COMMON -g)
 endif()

compiler-rt/lib/scudo/standalone/tests/CMakeLists.txt

list(APPEND SCUDO_UNITTEST_CFLAGS -DGWP_ASAN_HOOKS -fno-omit-frame-pointer
        -mno-omit-leaf-frame-pointer)
 endif()
 
 set(SCUDO_TEST_ARCH ${SCUDO_STANDALONE_SUPPORTED_ARCH})
 
 # gtests requires c++
 set(SCUDO_UNITTEST_LINK_FLAGS
   ${COMPILER_RT_UNITTEST_LINK_FLAGS}
+  ${COMPILER_RT_UNWINDER_LINK_LIBS}
   ${SANITIZER_TEST_CXX_LIBRARIES})
 list(APPEND SCUDO_UNITTEST_LINK_FLAGS -pthread -no-pie)
 # Linking against libatomic is required with some compilers
 check_library_exists(atomic __atomic_load_8 "" COMPILER_RT_HAS_LIBATOMIC)
 if (COMPILER_RT_HAS_LIBATOMIC)
   list(APPEND SCUDO_UNITTEST_LINK_FLAGS -latomic)
 endif()
 

compiler-rt/lib/tsan/tests/CMakeLists.txt

 endif()
 
 append_list_if(COMPILER_RT_HAS_MSSE4_2_FLAG -msse4.2 TSAN_UNITTEST_CFLAGS)
 
 set(TSAN_TEST_ARCH ${TSAN_SUPPORTED_ARCH})
 
 set(TSAN_UNITTEST_LINK_FLAGS
   ${COMPILER_RT_UNITTEST_LINK_FLAGS}
+  ${COMPILER_RT_UNWINDER_LINK_LIBS}
   ${SANITIZER_TEST_CXX_LIBRARIES})
 
 if(APPLE)
 
   # Create a static library for test dependencies.
   set(TSAN_TEST_RUNTIME_OBJECTS
     $<TARGET_OBJECTS:RTTsan_dynamic.osx>
     $<TARGET_OBJECTS:RTInterception.osx>