diff --git a/src/test/ui/coherence/auxiliary/coherence_lib.rs b/src/test/ui/coherence/auxiliary/coherence_lib.rs
index 9a5ec824306..c22819831ab 100644
--- a/src/test/ui/coherence/auxiliary/coherence_lib.rs
+++ b/src/test/ui/coherence/auxiliary/coherence_lib.rs
@@ -5,11 +5,11 @@ pub trait Remote {
 }
 
 pub trait Remote1<T> {
-    fn foo(&self, t: T) { }
+    fn foo(&self, _t: T) { }
 }
 
 pub trait Remote2<T, U> {
-    fn foo(&self, t: T, u: U) { }
+    fn foo(&self, _t: T, _u: U) { }
 }
 
 pub struct Pair<T,U>(T,U);