diff --git a/ipld/amt/benches/amt_benchmark.rs b/ipld/amt/benches/amt_benchmark.rs
index c3827b7221..90c26386ff 100644
--- a/ipld/amt/benches/amt_benchmark.rs
+++ b/ipld/amt/benches/amt_benchmark.rs
@@ -33,6 +33,7 @@ impl<'de> Deserialize<'de> for BenchData {
     where
         D: Deserializer<'de>,
     {
+        #[allow(let_unit_value)]
         let _s: () = Deserialize::deserialize(deserializer)?;
 
         Ok(Self::default())