diff --git a/src/clients/query-controller.hpp b/src/clients/query-controller.hpp
index 7729ea2..8a84645 100644
--- a/src/clients/query-controller.hpp
+++ b/src/clients/query-controller.hpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
-/**
- * Copyright (c) 2014, Regents of the University of California.
+/*
+ * Copyright (c) 2014-2018, Regents of the University of California.
  *
  * This file is part of NDNS (Named Data Networking Domain Name Service).
  * See AUTHORS.md for complete list of NDNS authors and contributors.
@@ -56,6 +56,9 @@
                   const QuerySucceedCallback& onSucceed, const QueryFailCallback& onFail,
                   Face& face);
 
+  virtual
+  ~QueryController() = default;
+
   /**
    * @brief start query process.
    */