[Boost-users] [serialization] Issues with/questions about polymorphic archives

I'm seeing the following error when trying to serialize from a polymorphic_iarchive. I'm new to boost::serialization, so I was hoping somebody could shed some light on what I was doing wrong? I tried googling and searching the archives, but didn't find anything yet. error C2678: binary '>>' : no operator found which takes a left-hand operand of type 'const boost::archive::polymorphic_iarchive' (or there is no acceptable conversion) c:\boost\include\boost-1_35\boost\archive\detail\interface_iarchive.hpp(62): could be 'Archive &boost::archive::detail::interface_iarchive<Archive>::operator >>(const boost::serialization::nvp<T> &)' The code in question is essentially: virtual void foo(const boost::archive::polymorphic_iarchive& ar) { ar >> boost::serialization::make_nvp("typeName", *typePtr); ... } Also, it appears as though get_library_version() is private for polymorphic_iarchive_dispatch. I'm confused, isn't it public elsewhere? I was hoping to have access to it. I reckon there's a reason behind this, so I'm just curious as to why it's private. Thanks!