When I try to compile an application that uses the Boost serialization library, I get some compilation errors that I don't understand. I've taken the code, and trimmed it down to the simplest possible case that produces the same error. Here's the code: // Test of Boost serialization library #include <sstream> #include class test_t { public: int i; template <class Archive> void serialize(Archive& ar, const unsigned int version ) { ar & i; } test_t(int _i) : i(_i) {}; }; int main(void) { std::ostringstream oss; boost::archive::text_oarchive oa(oss); test_t test(1); oa << test; return 0; } When I compile this (gcc 4.1.2, Boost 1.33.1, under Fedora 7), I get the following error: g++ serialization_test.cpp -l boost_serialization /usr/include/boost/archive/detail/oserializer.hpp: In function ‘void boost::archive::save(Archive&, T&) [with Archive = boost::archive::text_oarchive, T = test_t]’: /usr/include/boost/archive/basic_text_oarchive.hpp:78: instantiated from ‘void boost::archive::basic_text_oarchive<Archive>::save_override(T&, int) [with T = test_t, Archive = boost::archive::text_oarchive]’ /usr/include/boost/archive/detail/interface_oarchive.hpp:78: instantiated from ‘Archive& boost::archive::detail::interface_oarchive<Archive>::operator<<(T&) [with T = test_t, Archive = boost::archive::text_oarchive]’ serialization_test.cpp:21: instantiated from here /usr/include/boost/archive/detail/oserializer.hpp:567: error: invalid application of ‘sizeof’ to incomplete type ‘boost::STATIC_ASSERTION_FAILURE<false>’ Can someone explain to me WTF is going on? That error makes absolutely no sense at all to me, and I'm at my wits end! Thanks, -- Dominick