[Sanitizer tests] Don't need to use -lstdc++ thanks to --driver-mode=g++

[samsonov]

LGTM

[timurrrr]

Landed as r209115, thanks!

cmake/config-ix.cmake

 check_cxx_compiler_flag(/W3 COMPILER_RT_HAS_W3_FLAG)
 check_cxx_compiler_flag(/WX COMPILER_RT_HAS_WX_FLAG)
 check_cxx_compiler_flag(/wd4722 COMPILER_RT_HAS_WD4722_FLAG)
 
 # Symbols.
 check_symbol_exists(__func__ "" COMPILER_RT_HAS_FUNC_SYMBOL)
 
 # Libraries.
-check_library_exists(stdc++ __cxa_pure_virtual "" COMPILER_RT_HAS_LIBSTDCXX)
 check_library_exists(m pow "" COMPILER_RT_HAS_LIBM)
 check_library_exists(dl dlopen "" COMPILER_RT_HAS_LIBDL)
 check_library_exists(pthread pthread_create "" COMPILER_RT_HAS_LIBPTHREAD)

lib/asan/tests/CMakeLists.txt

 
 set(ASAN_BLACKLIST_FILE "${CMAKE_CURRENT_SOURCE_DIR}/asan_test.ignore")
 set(ASAN_UNITTEST_INSTRUMENTED_CFLAGS
   ${ASAN_UNITTEST_COMMON_CFLAGS}
   -fsanitize=address
   "-fsanitize-blacklist=${ASAN_BLACKLIST_FILE}"
 )
 
-# Unit tests require libstdc++ on POSIX.
-append_if(COMPILER_RT_HAS_LIBSTDCXX -lstdc++ ASAN_UNITTEST_COMMON_LINKFLAGS)
-
 if(NOT MSVC)
   list(APPEND ASAN_UNITTEST_COMMON_LINKFLAGS --driver-mode=g++)
 endif()
 
 # x86_64 FreeBSD 9.2 additionally requires libc++ to build the tests.
 if(CMAKE_SYSTEM MATCHES "FreeBSD-9.2-RELEASE")
   list(APPEND ASAN_UNITTEST_COMMON_LINKFLAGS "-lc++")
 endif()

lib/sanitizer_common/tests/CMakeLists.txt

list(APPEND SANITIZER_TEST_CFLAGS_COMMON
        -D_HAS_EXCEPTIONS=0)
 
   # We should teach clang-cl to understand more pragmas.
   list(APPEND SANITIZER_TEST_CFLAGS_COMMON
        -Wno-unknown-pragmas
        -Wno-undefined-inline)
 endif()
 
-append_if(COMPILER_RT_HAS_LIBSTDCXX -lstdc++ SANITIZER_TEST_LINK_FLAGS_COMMON)
+if(NOT MSVC)
+  list(APPEND SANITIZER_TEST_LINK_FLAGS_COMMON --driver-mode=g++)
+endif()
+
 append_if(COMPILER_RT_HAS_LIBDL -ldl SANITIZER_TEST_LINK_FLAGS_COMMON)
 append_if(COMPILER_RT_HAS_LIBPTHREAD -lpthread SANITIZER_TEST_LINK_FLAGS_COMMON)
 # x86_64 FreeBSD 9.2 additionally requires libc++ to build the tests.
 if(CMAKE_SYSTEM MATCHES "FreeBSD-9.2-RELEASE")
   list(APPEND SANITIZER_TEST_LINK_FLAGS_COMMON "-lc++")
 endif()
 
 include_directories(..)