diff --git a/llvm/lib/Support/Locale.cpp b/llvm/lib/Support/Locale.cpp
index d5cb72b5db3a..53bc0e36d830 100644
--- a/llvm/lib/Support/Locale.cpp
+++ b/llvm/lib/Support/Locale.cpp
@@ -1,3 +1,4 @@
+#include "llvm/Config/llvm-config.h"
 #include "llvm/Support/Locale.h"
 #include "llvm/Support/Unicode.h"