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diff --git a/boost/type_index/runtime_cast/detail/runtime_cast_impl.hpp b/boost/type_index/runtime_cast/detail/runtime_cast_impl.hpp
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+++ b/boost/type_index/runtime_cast/detail/runtime_cast_impl.hpp
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+//
+// Copyright (c) Chris Glover, 2016.
+//
+//
+// 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)
+//
+
+#ifndef BOOST_TYPE_INDEX_RUNTIME_CAST_DETAIL_RUNTIME_CAST_IMPL_HPP
+#define BOOST_TYPE_INDEX_RUNTIME_CAST_DETAIL_RUNTIME_CAST_IMPL_HPP
+
+/// \file runtime_cast_impl.hpp
+/// \brief Contains the overload of boost::typeindex::runtime_cast for
+/// pointer types.
+///
+/// boost::typeindex::runtime_cast can be used to emulate dynamic_cast
+/// functionality on platorms that don't provide it or should the user
+/// desire opt in functionality instead of enabling it system wide.
+
+#include <boost/type_index.hpp>
+#include <boost/type_traits/integral_constant.hpp>
+
+#ifdef BOOST_HAS_PRAGMA_ONCE
+# pragma once
+#endif
+
+namespace boost { namespace typeindex {
+
+namespace detail {
+
+template<typename T, typename U>
+T* runtime_cast_impl(U* u, boost::true_type) BOOST_NOEXCEPT {
+    return u;
+}
+
+template<typename T, typename U>
+T const* runtime_cast_impl(U const* u, boost::true_type) BOOST_NOEXCEPT {
+    return u;
+}
+
+template<typename T, typename U>
+T* runtime_cast_impl(U* u, boost::false_type) BOOST_NOEXCEPT {
+    return const_cast<T*>(static_cast<T const*>(
+        u->boost_type_index_find_instance_(boost::typeindex::type_id<T>())
+    ));
+}
+
+template<typename T, typename U>
+T const* runtime_cast_impl(U const* u, boost::false_type) BOOST_NOEXCEPT {
+    return static_cast<T const*>(u->boost_type_index_find_instance_(boost::typeindex::type_id<T>()));
+}
+
+} // namespace detail
+
+}} // namespace boost::typeindex
+
+#endif // BOOST_TYPE_INDEX_RUNTIME_CAST_DETAIL_RUNTIME_CAST_IMPL_HPP