ile, TEST_STREAM_FLAGS);
        test_iarchive ia(is, TEST_ARCHIVE_FLAGS);
        ia >> boost::serialization::make_nvp("ta", ta1);
    }
    std::remove(testfile);
    if(*ta != *ta1)
        return 1;

    return 0;
}
</code></pre>
Difficulties start to occur when the base class is made polymorphic by the designation
of one or more functions as "virtual".  If a class is polymorphic, the library
presumes that one will want the ability to serialize a derived class through
a pointer to the base class.  Inclu