diff --git a/serde/src/de/value.rs b/serde/src/de/value.rs
index 65ffe083..bdbfc29b 100644
--- a/serde/src/de/value.rs
+++ b/serde/src/de/value.rs
@@ -1390,7 +1390,6 @@ mod private {
 
     use de::{self, DeserializeSeed, Deserializer, MapAccess, Unexpected, VariantAccess, Visitor};
 
-    #[derive(Clone, Debug)]
     pub struct UnitOnly<E> {
         marker: PhantomData<E>,
     }