diff --git a/src/c_enum.rs b/src/c_enum.rs
index b1cef18..1b31759 100644
--- a/src/c_enum.rs
+++ b/src/c_enum.rs
@@ -89,7 +89,7 @@ macro_rules! c_enum
       {
          fn fmt(&self, f: &mut ::std::fmt::Formatter) -> ::std::fmt::Result
          {
-            write!(f, "{}", self.to_str())
+            ::std::fmt::Display::fmt(self, f)
          }
       }