I'm compiling with VS10, and using Boost 1.49.0 “reference member is initialized to a temporary that doesn't persist after the constructor exits” That does not sound good, and browsing through the mailing list archives I see discussions of regressions in 2010 that cite C4413 and use of emplace. I can't read the source code because it's just a ball of preprocessor stuff. Is this a real problem or a warning that can be ignored? I would think that if Boost.Container was broken on VS10, it would be mentioned somewhere where it's easy to spot. Thanks, —John E:\boost_1_49\boost/preprocessor/iteration/detail/local.hpp(37): warning C4413: 'boost::container::container_detail::advanced_insert_aux_non_movable_emplace1arg::m_p0' : reference member is initialized to a temporary that doesn't persist after the constructor exits with [ A=std::allocator, Iterator=std::tr1::shared_ptr<MyTypeA> *, P0=std::tr1::shared_ptr<MyTypeA> ] E:\boost_1_49\boost/preprocessor/iteration/detail/local.hpp(37) : see declaration of 'boost::container::container_detail::advanced_insert_aux_non_movable_emplace1arg::m_p0' with [ A=std::allocator, Iterator=std::tr1::shared_ptr<MyTypeA> *, P0=std::tr1::shared_ptr<MyTypeA> ] E:\boost_1_49\boost/preprocessor/iteration/detail/local.hpp(37) : while compiling class template member function 'boost::container::container_detail::advanced_insert_aux_non_movable_emplace1arg::advanced_insert_aux_non_movable_emplace1arg(A &,P0 &&)' with [ A=std::allocator, Iterator=std::tr1::shared_ptr<MyTypeA> *, P0=std::tr1::shared_ptr<MyTypeA> ] E:\boost_1_49\boost/preprocessor/iteration/detail/local.hpp(37) : see reference to class template instantiation 'boost::container::container_detail::advanced_insert_aux_non_movable_emplace1arg' being compiled with [ A=std::allocator, Iterator=std::tr1::shared_ptr<MyTypeA> *, P0=std::tr1::shared_ptr<MyTypeA> ] E:\boost_1_49\boost/preprocessor/iteration/detail/local.hpp(37) : see reference to class template instantiation 'boost::container::container_detail::advanced_insert_aux_emplace1arg' being compiled with [ A=std::allocator, Iterator=std::tr1::shared_ptr<MyTypeA> *, P0=std::tr1::shared_ptr<MyTypeA> ] mysourcefile.cpp(172) : see reference to function template instantiation 'void boost::container::vector<T>::emplace_back>(P0 &&)' being compiled with [ T=std::tr1::shared_ptr<MyTypeA>, _Ty=MyTypeA, P0=std::tr1::shared_ptr<MyTypeA> ]