diff --git a/lib/System/CMakeLists.txt b/lib/System/CMakeLists.txt
index a5a56e832dc..431629a14d6 100644
--- a/lib/System/CMakeLists.txt
+++ b/lib/System/CMakeLists.txt
@@ -14,6 +14,7 @@ add_llvm_library(LLVMSystem
   Signals.cpp
   Threading.cpp
   TimeValue.cpp
+  ThreadLocal.cpp
   )
 
 if( BUILD_SHARED_LIBS AND NOT WIN32 )