Hi, Building 1.55 beta keeps failing on VC2013 RC. Trunk fails too IIRC. compile-c-c++ bin.v2\libs\date_time\build\msvc-12.0\debug\link-static\threading-multi\gregorian\greg_month.obj greg_month.cpp C:\VC\boost_1_55_0b1\boost/iterator/detail/facade_iterator_category.hpp(166) : error C2039: 'assert_not_arg' : is not a member of 'boost::mpl' C:\VC\boost_1_55_0b1\boost/mpl/eval_if.hpp(41) : see reference to class template instantiation 'boost::detail::facade_iterator_category_impl<CategoryOrTraversal,ValueParam,Reference>' being compiled with [ CategoryOrTraversal=boost::forward_traversal_tag , ValueParam=std::basic_string<char,std::char_traits<char>,std::allocator<char>> , Reference=const std::basic_string<char,std::char_traits<char>,std::allocator<char>> & ] C:\VC\boost_1_55_0b1\boost/iterator/detail/facade_iterator_category.hpp(193) : see reference to class template instantiation 'boost::mpl::eval_if<boost::detail::is_iterator_category<CategoryOrTraversal>,boost::mpl::identity<boost::forward_traversal_tag>,boost::detail::facade_iterator_category_impl<CategoryOrTra versal,ValueParam,Reference>>' being compiled with [ CategoryOrTraversal=boost::forward_traversal_tag , ValueParam=std::basic_string<char,std::char_traits<char>,std::allocator<char>> , Reference=const std::basic_string<char,std::char_traits<char>,std::allocator<char>> & ] C:\VC\boost_1_55_0b1\boost/iterator/iterator_facade.hpp(104) : see reference to class template instantiation 'boost::detail::facade_iterator_category<CategoryOrTraversal,ValueParam,Reference>' being compiled with [ CategoryOrTraversal=boost::forward_traversal_tag , ValueParam=std::basic_string<char,std::char_traits<char>,std::allocator<char>> , Reference=const std::basic_string<char,std::char_traits<char>,std::allocator<char>> & ] C:\VC\boost_1_55_0b1\boost/iterator/iterator_facade.hpp(620) : see reference to class template instantiation 'boost::detail::iterator_facade_types<Value,CategoryOrTraversal,Reference,Difference>' being compiled with [ Value=std::basic_string<char,std::char_traits<char>,std::allocator<char>> , CategoryOrTraversal=boost::forward_traversal_tag , Reference=const std::basic_string<char,std::char_traits<char>,std::allocator<char>> & , Difference=ptrdiff_t ] C:\VC\boost_1_55_0b1\boost/token_iterator.hpp(40) : see reference to class template instantiation 'boost::iterator_facade<boost::token_iterator<TokenizerFunc,Iterator,Type>,Type,boost::forward_traversal_tag,const Type &,ptrdiff_t>' being compiled with [ TokenizerFunc=char_separator_type , Iterator=std::_String_const_iterator<std::_String_val<std::_Simple_types<char>>> , Type=std::basic_string<char,std::char_traits<char>,std::allocator<char>> ] C:\VC\boost_1_55_0b1\boost/date_time/date_parsing.hpp(132) : see reference to class template instantiation 'boost::token_iterator<TokenizerFunc,Iterator,Type>' being compiled with [ TokenizerFunc=char_separator_type , Iterator=std::_String_const_iterator<std::_String_val<std::_Simple_types<char>>> , Type=std::basic_string<char,std::char_traits<char>,std::allocator<char>> ] C:\VC\boost_1_55_0b1\boost/date_time/gregorian/parsers.hpp(30) : see reference to function template instantiation 'date_type boost::date_time::parse_date<boost::gregorian::date>(const std::string &,int)' being compiled with [