build: switch to C++14
Cleanup core/common.hpp
Change-Id: I6566b0224e24716691d5896462aa7613547ed950
Refs: #3076
diff --git a/tools/ping/server/ping-server.cpp b/tools/ping/server/ping-server.cpp
index 08d17bf..0a94d0f 100644
--- a/tools/ping/server/ping-server.cpp
+++ b/tools/ping/server/ping-server.cpp
@@ -1,6 +1,6 @@
/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
-/**
- * Copyright (c) 2015, Arizona Board of Regents.
+/*
+ * Copyright (c) 2015-2018, Arizona Board of Regents.
*
* This file is part of ndn-tools (Named Data Networking Essential Tools).
* See AUTHORS.md for complete list of ndn-tools authors and contributors.
@@ -22,6 +22,8 @@
#include "ping-server.hpp"
+#include <ndn-cxx/security/signing-helpers.hpp>
+
namespace ndn {
namespace ping {
namespace server {