Simplified example (same problem): #include <stdexcept> #include <boost/serialization/nvp.hpp> #include <boost/serialization/export.hpp> struct overflow_policy_base2 { overflow_policy_base2 (double _min, double _max) : min (_min), max (_max) {} virtual double apply (double) = 0; double min, max; friend class boost::serialization::access; template<class Archive> inline void serialize (Archive &ar, const unsigned int) { ar & min; ar & max; } }; BOOST_IS_ABSTRACT (overflow_policy_base2) struct limit_policy2 : public overflow_policy_base2 { limit_policy2 (double _min, double _max) : overflow_policy_base2 (_min, _max) {} virtual double apply (double x) { if (x > this->max) return this->max; else if (x < this->min) return this->min; else return x; } template<class Archive> inline void serialize (Archive &ar, const unsigned int) { ar & BOOST_SERIALIZATION_BASE_OBJECT_NVP (overflow_policy_base2); } }; BOOST_CLASS_EXPORT (limit_policy2) g++ -I /usr/local/src/boost.cvs -xc++ -fsyntax-only test.hpp /usr/local/src/boost.cvs/boost/serialization/type_info_implementation.hpp: In instantiation of ‘boost::serialization::type_info_implementation<limit_policy2>’: /usr/local/src/boost.cvs/boost/serialization/export.hpp:76: instantiated from ‘boost::archive::detail::guid_initializer<limit_policy2>’ test.hpp:43: instantiated from here /usr/local/src/boost.cvs/boost/serialization/type_info_implementation.hpp:50: error: invalid use of undefined type ‘struct boost::serialization::extended_type_info_impl<limit_policy2>’ /usr/local/src/boost.cvs/boost/serialization/traits.hpp:42: error: declaration of ‘struct boost::serialization::extended_type_info_impl<limit_policy2>’