ceph/src/boost/libs/smart_ptr/include/boost/smart_ptr/detail/sp_forward.hpp

   1 #ifndef BOOST_SMART_PTR_DETAIL_SP_FORWARD_HPP_INCLUDED
   2 #define BOOST_SMART_PTR_DETAIL_SP_FORWARD_HPP_INCLUDED
   3
   4 // MS compatible compilers support #pragma once
   5
   6 #if defined(_MSC_VER) && (_MSC_VER >= 1020)
   7 # pragma once
   8 #endif
   9
  10 //  detail/sp_forward.hpp
  11 //
  12 //  Copyright 2008,2012 Peter Dimov
  13 //
  14 //  Distributed under the Boost Software License, Version 1.0.
  15 //  See accompanying file LICENSE_1_0.txt or copy at
  16 //  http://www.boost.org/LICENSE_1_0.txt
  17
  18 #include <boost/config.hpp>
  19
  20 namespace boost
  21 {
  22
  23 namespace detail
  24 {
  25
  26 #if !defined( BOOST_NO_CXX11_RVALUE_REFERENCES )
  27
  28 #if defined( BOOST_GCC ) && __GNUC__ * 100 + __GNUC_MINOR__ <= 404
  29
  30 // GCC 4.4 supports an outdated version of rvalue references and creates a copy of the forwarded object.
  31 // This results in warnings 'returning reference to temporary'. Therefore we use a special version similar to std::forward.
  32 template< class T > T&& sp_forward( T && t ) BOOST_NOEXCEPT
  33 {
  34     return t;
  35 }
  36
  37 #else
  38
  39 template< class T > T&& sp_forward( T & t ) BOOST_NOEXCEPT
  40 {
  41     return static_cast< T&& >( t );
  42 }
  43
  44 #endif
  45
  46 #endif
  47
  48 } // namespace detail
  49
  50 } // namespace boost
  51
  52 #endif  // #ifndef BOOST_SMART_PTR_DETAIL_SP_FORWARD_HPP_INCLUDED