diff --git a/include/llvm/Support/MD5.h b/include/llvm/Support/MD5.h
index b2b8c2d55b8..4eb8507ea34 100644
--- a/include/llvm/Support/MD5.h
+++ b/include/llvm/Support/MD5.h
@@ -28,13 +28,12 @@
 #ifndef LLVM_SYSTEM_MD5_H
 #define LLVM_SYSTEM_MD5_H
 
+#include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/Support/DataTypes.h"
 
 namespace llvm {
 
-template <typename T> class ArrayRef;
-
 class MD5 {
   // Any 32-bit or wider unsigned integer data type will do.
   typedef uint32_t MD5_u32plus;