diff --git a/llvm/include/llvm/Transforms/Scalar.h b/llvm/include/llvm/Transforms/Scalar.h
index 237975216f04..dbf76c3bbee0 100644
--- a/llvm/include/llvm/Transforms/Scalar.h
+++ b/llvm/include/llvm/Transforms/Scalar.h
@@ -185,7 +185,7 @@ Pass *createLoopUnrollPass(int OptLevel = 2, int Threshold = -1, int Count = -1,
                            int AllowPartial = -1, int Runtime = -1,
                            int UpperBound = -1);
 // Create an unrolling pass for full unrolling that uses exact trip count only.
-Pass *createSimpleLoopUnrollPass(int OptLevel);
+Pass *createSimpleLoopUnrollPass(int OptLevel = 2);
 
 //===----------------------------------------------------------------------===//
 //