diff --git a/include/util/query_heap.hpp b/include/util/query_heap.hpp
index 2e2944287..57b7cfb35 100644
--- a/include/util/query_heap.hpp
+++ b/include/util/query_heap.hpp
@@ -34,7 +34,7 @@ template <typename NodeID, typename Key> class ArrayStorage
 template <typename NodeID, typename Key> class UnorderedMapStorage
 {
   public:
-    explicit UnorderedMapStorage(std::size_t)
+    explicit UnorderedMapStorage(std::size_t) {}
 
     Key &operator[](const NodeID node) { return nodes[node]; }