Hello While i was trying to run the folowing code: #include "FaceBase.h" int main() { FaceBase< EigMemberProps<int,std::string> > F(std::string("facebase.archive")); return 0; } I get the error message : /.../boost/serialization/singleton.hpp:124: static T& boost::serialization::singleton<T>::get_instance() [with T = boost::archive::detail::iserializer<boost::archive::text_iarchive, std::vector<EigMemberProps<int, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<EigMemberProps<int, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > > > >]: Assertion `! detail::singleton_wrapper<T>::m_is_destroyed' failed. But the strangest it that this happen before the first instruction (the FaceBase constructor is not call). However, if i retrive the text_oarchive and text_iarchive calls in constructor and destructors, it works fine.... do you have any clue about this error ? Thanks.