diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 19169f6..a38b204 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -3685,7 +3685,8 @@
 bool
 SelectionDAGBuilder::EmitFuncArgumentDbgValue(const DbgValueInst &DI,
                                               const Value *V, MDNode *Variable,
-                                              uint64_t Offset, SDValue &N) {
+                                              uint64_t Offset,
+                                              const SDValue &N) {
   if (!isa<Argument>(V))
     return false;
 
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.h b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.h
index baed7e6..3fcd4b9 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.h
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.h
@@ -500,7 +500,7 @@
   /// the entry BB.
   bool EmitFuncArgumentDbgValue(const DbgValueInst &DI,
                                 const Value *V, MDNode *Variable,
-                                uint64_t Offset, SDValue &N);
+                                uint64_t Offset, const SDValue &N);
 };
 
 } // end namespace llvm