# must fail: union_O10_layers union_O10_repeated_layer_after_first union_O10_repeated_layer_after_second
# a layer joins no alt (codecs::described)
diff --git a/wai/wai-rs/src/http_binding/codecs.rs b/wai/wai-rs/src/http_binding/codecs.rs
index a4d35e39..821b7f51 100644
--- a/wai/wai-rs/src/http_binding/codecs.rs
+++ b/wai/wai-rs/src/http_binding/codecs.rs
@@ -334,7 +334,7 @@ fn described(objects: &[SeqObject]) -> Result<Vec<Element>, CodecsError> {
             let el = els[k].as_mut().expect("a base is not a layer");
             let alt = el.alts.iter_mut().find(|a| a.cap == base_cap)
                 .ok_or_else(|| CodecsError::LayerUnbound(format!("wai.{cap}: its base's capability is not dispatched")))?;
-            push_unique(&mut alt.plus, cap.clone());
+            let _ = (alt, &cap);
         }
     }
     Ok(els.into_iter().flatten().collect())