After seeing the announcement that library freeze is coming, I just tried building the master snapshot with the build scripts I use for building the windows releases. I encountered failures in msvc-10.0 and msvc-11.0 for ASIO. .\boost/asio/execution/any_executor.hpp(940) : error C2668: 'boost::asio::execution::detail::any_executor_base::query_fn_impl' : ambiguous call to overloaded function .\boost/asio/execution/any_executor.hpp(915): could be 'void boost::asio::execution::detail::any_executor_base::query_fn_impl(void *,const void *,const void *,boost::type *)' with [ Ex=void, Prop=boost::asio::execution::context_as_t ] .\boost/asio/execution/any_executor.hpp(902): or 'void boost::asio::execution::detail::any_executor_base::query_fn_impl(void *,const void *,const void *,boost::type *)' with [ Ex=void, Prop=boost::asio::execution::context_as_t ] .\boost/asio/execution/any_executor.hpp(887): or 'void boost::asio::execution::detail::any_executor_base::query_fn_impl(void *,const void *,const void *,boost::type *)' with [ Ex=void, Prop=boost::asio::execution::context_as_t ] .\boost/asio/execution/any_executor.hpp(875): or 'void boost::asio::execution::detail::any_executor_base::query_fn_impl(void *,const void *,const void *,boost::type *)' with [ Ex=void, Prop=boost::asio::execution::context_as_t ] .\boost/asio/execution/any_executor.hpp(859): or 'void boost::asio::execution::detail::any_executor_base::query_fn_impl(void *,const void *,const void *,boost::type *)' with [ Ex=void, Prop=boost::asio::execution::context_as_t ] .\boost/asio/execution/any_executor.hpp(849): or 'void boost::asio::execution::detail::any_executor_base::query_fn_impl(void *,const void *,const void *,boost::type *)' with [ Ex=void, Prop=boost::asio::execution::context_as_t ] .\boost/asio/execution/any_executor.hpp(837): or 'void boost::asio::execution::detail::any_executor_base::query_fn_impl(void *,const void *,const void *,boost::type *)' with [ Ex=void, Prop=boost::asio::execution::context_as_t ] .\boost/asio/execution/any_executor.hpp(827): or 'void boost::asio::execution::detail::any_executor_base::query_fn_impl(void *,const void *,const void *,void *)' with [ Ex=void, Prop=boost::asio::execution::context_as_t ] while trying to match the argument list '(void *, const void *, const void *, int)' .\boost/asio/execution/any_executor.hpp(1782) : see reference to function template instantiation 'void boost::asio::execution::detail::any_executor_base::query_fn(void *,const void *,const void *)' being compiled with [ Ex=void, T1=boost::asio::execution::context_as_t ] .\boost/asio/execution/any_executor.hpp(1782) : see reference to function template instantiation 'const boost::asio::execution::detail::any_executor_base::prop_fns<Poly> *boost::asio::execution::any_executor<<unnamed-symbol>,boost::asio::execution::detail::blocking::never_t<I>,boost::asio::execution::prefer_only<InnerProperty>,boost::asio::execution::prefer_only>,boost::asio::execution::prefer_only>,boost::asio::execution::prefer_only>,boost::asio::execution::prefer_only>>::prop_fns_table<void>(void)' being compiled with [ Poly=boost::asio::execution::any_executor,boost::asio::execution::detail::blocking::never_t<0>,boost::asio::execution::prefer_only>,boost::asio::execution::prefer_only>,boost::asio::execution::prefer_only>,boost::asio::execution::prefer_only>,boost::asio::execution::prefer_only>>, <unnamed-symbol>=boost::asio::execution::context_as_t, I=0, InnerProperty=boost::asio::execution::detail::blocking::possibly_t<0> ] .\boost/asio/execution/any_executor.hpp(1782) : while compiling class template member function 'boost::asio::execution::any_executor<<unnamed-symbol>,boost::asio::execution::detail::blocking::never_t<I>,boost::asio::execution::prefer_only<InnerProperty>,boost::asio::execution::prefer_only>,boost::asio::execution::prefer_only>,boost::asio::execution::prefer_only>,boost::asio::execution::prefer_only>>::any_executor(void)' with [ <unnamed-symbol>=boost::asio::execution::context_as_t, I=0, InnerProperty=boost::asio::execution::detail::blocking::possibly_t<0> ] .\boost/asio/detail/io_object_impl.hpp(168) : see reference to class template instantiation 'boost::asio::execution::any_executor<<unnamed-symbol>,boost::asio::execution::detail::blocking::never_t<I>,boost::asio::execution::prefer_only<InnerProperty>,boost::asio::execution::prefer_only>,boost::asio::execution::prefer_only>,boost::asio::execution::prefer_only>,boost::asio::execution::prefer_only>>' being compiled with [ <unnamed-symbol>=boost::asio::execution::context_as_t, I=0, InnerProperty=boost::asio::execution::detail::blocking::possibly_t<0> ] .\boost/asio/basic_socket.hpp(1804) : see reference to class template instantiation 'boost::asio::detail::io_object_impl' being compiled with [ IoObjectService=boost::asio::detail::win_iocp_socket_serviceboost::asio::ip::udp, Executor=boost::asio::any_io_executor ] .\boost/asio/basic_datagram_socket.hpp(53) : see reference to class template instantiation 'boost::asio::basic_socket' being compiled with [ Protocol=boost::asio::ip::udp, Executor=boost::asio::any_io_executor ] libs\log\src\syslog_backend.cpp(315) : see reference to class template instantiation 'boost::asio::basic_datagram_socket<Protocol>' being compiled with [ Protocol=boost::asio::ip::udp ] Hopefully this can be cleared up before the beta. Thanks, Tom