Index: libcxx/trunk/lib/CMakeLists.txt
===================================================================
--- libcxx/trunk/lib/CMakeLists.txt
+++ libcxx/trunk/lib/CMakeLists.txt
@@ -42,6 +42,8 @@
     set(LIBFILE "libclang_rt.asan_osx_dynamic.dylib")
   elseif("${LLVM_USE_SANITIZER}" STREQUAL "Undefined")
     set(LIBFILE "libclang_rt.ubsan_osx_dynamic.dylib")
+  elseif("${LLVM_USE_SANITIZER}" STREQUAL "Thread")
+    set(LIBFILE "libclang_rt.tsan_osx_dynamic.dylib")
   else()
     message(WARNING "LLVM_USE_SANITIZER=${LLVM_USE_SANITIZER} is not supported on OS X")
   endif()