diff --git a/cmake/functions.cmake b/cmake/functions.cmake
index 3bfd343..23538e6 100644
--- a/cmake/functions.cmake
+++ b/cmake/functions.cmake
@@ -85,6 +85,10 @@ macro(google_initialize_cartographer_project)
   google_add_flag(GOOG_CXX_FLAGS "-Werror=switch")
   google_add_flag(GOOG_CXX_FLAGS "-Werror=uninitialized")
 
+  if (CMAKE_CXX_COMPILER_ID MATCHES "Clang" OR CMAKE_CXX_COMPILER_ID MATCHES "AppleClang")
+    google_add_flag(GOOG_CXX_FLAGS "-Wthread-safety")
+  endif()
+
   if(NOT CMAKE_BUILD_TYPE OR CMAKE_BUILD_TYPE STREQUAL "")
     set(CMAKE_BUILD_TYPE Release)
   endif()