diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfExpression.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfExpression.cpp
index d614dfd..b66084b 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfExpression.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfExpression.cpp
@@ -178,7 +178,7 @@
   AddStackValue();
 }
 
-void DwarfExpression::AddUnsignedConstant(APInt Value) {
+void DwarfExpression::AddUnsignedConstant(const APInt &Value) {
   unsigned Size = Value.getBitWidth();
   const uint64_t *Data = Value.getRawData();