diff --git a/src/macro/MacroValue.cc b/src/macro/MacroValue.cc
index 8e5f316094a91407ddf700bbc27975f642473873..9cacf8f137164b59de544f11920a7800dde6eb5c 100644
--- a/src/macro/MacroValue.cc
+++ b/src/macro/MacroValue.cc
@@ -275,9 +275,7 @@ IntMV::operator!() const noexcept(false)
 string
 IntMV::toString() const
 {
-  ostringstream ss;
-  ss << value;
-  return ss.str();
+  return to_string(value);
 }
 
 string