diff --git a/llvm/include/llvm/ADT/SmallVector.h b/llvm/include/llvm/ADT/SmallVector.h
index d972ea6e844f..e3aec7fec050 100644
--- a/llvm/include/llvm/ADT/SmallVector.h
+++ b/llvm/include/llvm/ADT/SmallVector.h
@@ -136,6 +136,11 @@ public:
     }
   }
   
+  void reserve(unsigned N) {
+    if (unsigned(Capacity-Begin) < N)
+      grow(N);
+  }
+  
   void swap(SmallVectorImpl &RHS);
   
   /// append - Add the specified range to the end of the SmallVector.