Boost C++ Libraries: Ticket #9021: Cannot export boost::iostreams::source implementation on MSVC

Boost C++ Libraries: Ticket #9021: Cannot export boost::iostreams::source implementation on MSVC https://svn.boost.org/trac10/ticket/9021 The following fails on MSVC 10 (VS2010) and MSVC 11 (VS2012) at least: <blockquote> #include <boost/iostreams/concepts.hpp> class declspec(dllexport) mystream : public boost::iostreams::source {}; </blockquote> with the error: <blockquote> error C2338: (is_convertible<Mode, two_sequence>::value) </blockquote> in concepts.hpp line 47. The same think happens with a sink. Are custom sources and sinks not meant to be exported from a library? en-us Boost C++ Libraries /htdocs/site/boost.png https://svn.boost.org/trac10/ticket/9021 Trac 1.4.3