diff --git a/runtime/src/accounts_db.rs b/runtime/src/accounts_db.rs
index cde46e8e2ec06f..271bed01e88044 100644
--- a/runtime/src/accounts_db.rs
+++ b/runtime/src/accounts_db.rs
@@ -332,7 +332,7 @@ pub struct AccountsDBSerialize<'a> {
     slot: Slot,
 }
 
-#[cfg(test)]
+#[cfg(all(test, RUSTC_IS_STABLE))]
 mod test_accounts_db_serialize {
     use super::*;