diff --git a/include/llvm/Linker/Linker.h b/include/llvm/Linker/Linker.h
index d1c02c241d5..4d1a32d7810 100644
--- a/include/llvm/Linker/Linker.h
+++ b/include/llvm/Linker/Linker.h
@@ -11,8 +11,8 @@
 #define LLVM_LINKER_LINKER_H
 
 #include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/STLExtras.h"
 
-#include <functional>
 
 namespace llvm {
 class DiagnosticInfo;
@@ -25,7 +25,7 @@ class StructType;
 /// something with it after the linking.
 class Linker {
   public:
-    typedef std::function<void(const DiagnosticInfo &)>
+    typedef function_ref<void(const DiagnosticInfo &)>
         DiagnosticHandlerFunction;
 
     Linker(Module *M, DiagnosticHandlerFunction DiagnosticHandler);