From 2a50f7caad405bb976e726c3663285f521e236e0 Mon Sep 17 00:00:00 2001
From: Joel de Guzman <djowel@gmail.com>
Date: Wed, 19 Nov 2014 08:31:35 +0800
Subject: [PATCH] Better patch from Kohei Takahashi! Allows good forwarding on
 C++11 while still allowing C++03.

---
 include/boost/fusion/support/pair.hpp | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/include/boost/fusion/support/pair.hpp b/include/boost/fusion/support/pair.hpp
index a01b79bd..965810de 100644
--- a/include/boost/fusion/support/pair.hpp
+++ b/include/boost/fusion/support/pair.hpp
@@ -16,6 +16,7 @@
 #include <boost/config.hpp>
 #include <boost/utility/enable_if.hpp>
 #include <boost/type_traits/is_convertible.hpp>
+#include <boost/type_traits/is_lvalue_reference.hpp>
 
 #if defined (BOOST_MSVC)
 #  pragma warning(push)
@@ -48,6 +49,17 @@ namespace boost { namespace fusion
         pair(typename detail::call_param<Second>::type val)
             : second(val) {}
 
+#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
+
+        BOOST_FUSION_GPU_ENABLED
+        template <typename Second2>
+        pair(Second2&& val
+          , typename boost::disable_if<is_lvalue_reference<Second2> >::type* /* dummy */ = 0
+          , typename boost::enable_if<is_convertible<Second2, Second> >::type* /*dummy*/ = 0
+        ) : second(std::forward<Second>(val)) {}
+
+#endif
+
         template <typename Second2>
         BOOST_FUSION_GPU_ENABLED
         pair(pair<First, Second2> const& rhs)