Enable tsan-instrumented libcxx on Darwin

[ismailp]

Summary

Instrumented libcxx depends on symbols that are exported by TSan RTL.

[samsonov]

cmake/Modules/AddCompilerRT.cmake

285

This should be handled by Clang driver, whenever we link a dynamic library with -fsanitize=thread.

cmake/Modules/AddCompilerRT.cmake

macro(add_custom_libcxx name prefix)
   foreach(flag ${LIBCXX_CFLAGS})
     set(flagstr "${flagstr} ${flag}")
   endforeach()
   set(LIBCXX_CFLAGS ${flagstr})
 
   if(NOT COMPILER_RT_STANDALONE_BUILD)
     list(APPEND LIBCXX_DEPS clang)
   endif()
+  set(LIBCXX_SHARED_LINKER_FLAGS)
+  if (APPLE)
+    set(LIBCXX_SHARED_LINKER_FLAGS "-undefined dynamic_lookup")
+  endif()
 
   ExternalProject_Add(${name}
     PREFIX ${prefix}
     SOURCE_DIR ${COMPILER_RT_LIBCXX_PATH}
     CMAKE_ARGS -DCMAKE_C_COMPILER=${COMPILER_RT_TEST_COMPILER}
                -DCMAKE_CXX_COMPILER=${COMPILER_RT_TEST_COMPILER}
                -DCMAKE_C_FLAGS=${LIBCXX_CFLAGS}
                -DCMAKE_CXX_FLAGS=${LIBCXX_CFLAGS}
                -DCMAKE_BUILD_TYPE=Release
+               -DCMAKE_SHARED_LINKER_FLAGS=${LIBCXX_SHARED_LINKER_FLAGS}
                -DCMAKE_INSTALL_PREFIX:PATH=<INSTALL_DIR>
     LOG_BUILD 1
     LOG_CONFIGURE 1
     LOG_INSTALL 1
     )
   set_target_properties(${name} PROPERTIES EXCLUDE_FROM_ALL TRUE)
 
   ExternalProject_Add_Step(${name} force-reconfigure

test/tsan/CMakeLists.txt

 set(TSAN_TEST_DEPS ${SANITIZER_COMMON_LIT_TEST_DEPS})
 if(NOT ${COMPILER_RT_DEFAULT_TARGET_ARCH} MATCHES "mips" AND NOT APPLE)
   list(APPEND TSAN_TEST_DEPS GotsanRuntimeCheck)
 endif()
 if(NOT COMPILER_RT_STANDALONE_BUILD)
   list(APPEND TSAN_TEST_DEPS tsan)
 endif()
 if(COMPILER_RT_HAS_LIBCXX_SOURCES AND
-   COMPILER_RT_TEST_COMPILER_ID STREQUAL "Clang"
-   AND NOT APPLE)
+   COMPILER_RT_TEST_COMPILER_ID STREQUAL "Clang")
   list(APPEND TSAN_TEST_DEPS libcxx_tsan)
   set(TSAN_HAS_LIBCXX True)
 else()
   set(TSAN_HAS_LIBCXX False)
 endif()
 
 configure_lit_site_cfg(
   ${CMAKE_CURRENT_SOURCE_DIR}/lit.site.cfg.in

test/tsan/lit.cfg

if config.compiler_id == 'GNU':
   extra_cflags = ["-fPIE", "-pthread", "-ldl", "-lstdc++", "-lrt", "-pie"]
 else:
   extra_cflags = []
 
 # Setup default compiler flags used with -fsanitize=thread option.
 clang_tsan_cflags = ["-fsanitize=thread",
                      "-Wall",
                      "-m64"] + config.debug_info_flags + extra_cflags
+if config.host_os == 'Darwin':
+  clang_tsan_cflags.extend(["-isystem", os.path.join(config.test_source_root)])
+
 clang_tsan_cxxflags = config.cxx_mode_flags + clang_tsan_cflags
 # Add additional flags if we're using instrumented libc++.
 # Instrumented libcxx currently not supported on Darwin.
 if config.has_libcxx and config.host_os != 'Darwin':
   # FIXME: Dehardcode this path somehow.
   libcxx_path = os.path.join(config.compiler_rt_obj_root, "lib",
                              "tsan", "libcxx_tsan")
   libcxx_incdir = os.path.join(libcxx_path, "include", "c++", "v1")
   libcxx_libdir = os.path.join(libcxx_path, "lib")
+  if config.host_os == 'Darwin':
+    libcxx_so = os.path.join(libcxx_libdir, "libc++.dylib")
+    rpath_flag = '-Wl,-rpath,%s' % libcxx_so
+  else:
     libcxx_so = os.path.join(libcxx_libdir, "libc++.so")
+    rpath_flag = '-Wl,-rpath=%s' % libcxx_so
   clang_tsan_cxxflags += ["-std=c++11",
                           "-I%s" % libcxx_incdir,
                           libcxx_so,
-                          "-Wl,-rpath=%s" % libcxx_libdir]
+                          rpath_flag]
 
 def build_invocation(compile_flags):
   return " " + " ".join([config.clang] + compile_flags) + " "
 
 config.substitutions.append( ("%clang_tsan ", build_invocation(clang_tsan_cflags)) )
 config.substitutions.append( ("%clangxx_tsan ", build_invocation(clang_tsan_cxxflags)) )
 
 # Define CHECK-%os to check for OS-dependent output.