diff --git a/src/test/run-pass/issue-511.rs b/src/test/run-pass/issue-511.rs
index e895598c92b..a545f751af9 100644
--- a/src/test/run-pass/issue-511.rs
+++ b/src/test/run-pass/issue-511.rs
@@ -1,7 +1,7 @@
 use std;
 import std::option;
 
-fn f<@T>(&o: mutable option::t<T>) {
+fn f<@T>(&o: option::t<T>) {
     assert o == option::none;
 }