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diff --git a/boost/chrono/round.hpp b/boost/chrono/round.hpp
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+//  boost/chrono/round.hpp  ------------------------------------------------------------//
+
+//  (C) Copyright Howard Hinnant
+//  Copyright 2011 Vicente J. Botet Escriba
+
+//  Distributed under the Boost Software License, Version 1.0. (See accompanying
+//  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+
+//  See http://www.boost.org/libs/chrono for documentation.
+
+#ifndef BOOST_CHRONO_ROUND_HPP
+#define BOOST_CHRONO_ROUND_HPP
+
+#include <boost/chrono/duration.hpp>
+#include <boost/chrono/duration.hpp>
+//#include <boost/chrono/typeof/boost/chrono/chrono.hpp>
+
+namespace boost
+{
+  namespace chrono
+  {
+
+    /**
+     * rounds to nearest, to even on tie
+     */
+    template <class To, class Rep, class Period>
+    To round(const duration<Rep, Period>& d)
+    {
+        To t0 = duration_cast<To>(d);
+        To t1 = t0;
+        ++t1;
+#if 0
+        // Avoid the user of BOOST_AUTO to make the library portable to Sun, PGI, ..
+        BOOST_AUTO(diff0, d - t0);
+        BOOST_AUTO(diff1, t1 - d);
+#else
+        typedef typename common_type<To, duration<Rep, Period> >::type  result_type;
+        result_type diff0 = d - t0;
+        result_type diff1 = t1 - d;
+#endif
+        if (diff0 == diff1)
+        {
+            if (t0.count() & 1)
+                return t1;
+            return t0;
+        }
+        else if (diff0 < diff1)
+            return t0;
+        return t1;
+    }
+
+  } // namespace chrono
+} // namespace boost
+
+#endif