Index: llvm/include/llvm/Support/TimeProfiler.h
===================================================================
--- llvm/include/llvm/Support/TimeProfiler.h
+++ llvm/include/llvm/Support/TimeProfiler.h
@@ -9,12 +9,19 @@
 #ifndef LLVM_SUPPORT_TIME_PROFILER_H
 #define LLVM_SUPPORT_TIME_PROFILER_H
 
+#include "llvm/Config/llvm-config.h"
 #include "llvm/Support/raw_ostream.h"
 
+#if LLVM_ENABLE_THREADS
+#define THREAD_LOCAL_IF_THREADS_ENABLED thread_local
+#else
+#define THREAD_LOCAL_IF_THREADS_ENABLED
+#endif
+
 namespace llvm {
 
 struct TimeTraceProfiler;
-extern thread_local std::unique_ptr<TimeTraceProfiler>
+extern THREAD_LOCAL_IF_THREADS_ENABLED std::unique_ptr<TimeTraceProfiler>
     TimeTraceProfilerInstance;
 
 /// Initialize the time trace profiler.
Index: llvm/lib/Support/TimeProfiler.cpp
===================================================================
--- llvm/lib/Support/TimeProfiler.cpp
+++ llvm/lib/Support/TimeProfiler.cpp
@@ -33,7 +33,7 @@
 
 namespace llvm {
 
-thread_local std::unique_ptr<TimeTraceProfiler> TimeTraceProfilerInstance =
+THREAD_LOCAL_IF_THREADS_ENABLED std::unique_ptr<TimeTraceProfiler> TimeTraceProfilerInstance =
     nullptr;
 
 typedef duration<steady_clock::rep, steady_clock::period> DurationType;