diff --git a/src/set.rs b/src/set.rs
index b278e500f..a5d892df2 100644
--- a/src/set.rs
+++ b/src/set.rs
@@ -2834,6 +2834,7 @@ mod test_set {
     fn test_replace() {
         use core::hash;
 
+        #[allow(dead_code)] // Having an unused field is the point of this test
         #[derive(Debug)]
         struct Foo(&'static str, i32);