diff --git a/Utilities/GNU.h b/Utilities/GNU.h
index 6bf8c7c886..268318e568 100644
--- a/Utilities/GNU.h
+++ b/Utilities/GNU.h
@@ -23,7 +23,7 @@
 #if defined(_MSC_VER)
 #define force_inline __forceinline
 #else
-#define force_inline __attribute__((always_inline))
+#define force_inline __attribute__((always_inline)) inline
 #endif
 
 #if defined(_MSC_VER) && _MSC_VER <= 1800