does the header file of polymorphic_derived1's include the following? BOOST_CLASS_TYPE_INFO( polymorphic_derived1, extended_type_info_no_rtti ) Also, the *.cpp file of polymorphic_derived1 should contain BOOST_CLASS_EXPORT(polymorphic_derived1) Robert Ramey "Daniel Roberts" wrote in message news:14125aaf0901151528p8f354ffp9409248decf7958c@mail.gmail.com... Thanks for the response. Yes, I am using the no rtti option. I downloaded test_no_rtti.cpp and got it to work as-is. I then made the following changes: 1) Move polymorphic_base's definition into its own header file. 2) Move polymorphic_derived1's definition into its own header file. 3) Move the definition of polymorphic_derived1::get_key() into an implementation file. Making these changes causes the assertion failure. I am using boost v1.36.0 and Visual Studio 2008 9.0.30729.1 SP Thanks, Daniel Roberts I presume you're using the "no rtti" option? get_key used only for those systems which use which depend on extended_type_info_no_rtti to handle extended_type_info functionality. with which compiler?, which version of boost? "Daniel Roberts" wrote in message news: 14125aaf0901142057s6ba59d08tc98a6990a5f78bca@mail.gmail.com... I have a derived class that exports its type and overrides get_key for serialization through a base class pointer. If I move the definition of the overridden get_key function out of the header into a cpp file, an assertion fails on line 49 of extended_type_info.cpp. Take a look at the example "test_no_rtti". the class polymorphic_derived has a get_key declaration - but the get_key definition is not inline. This would seem identical your case. You might want to make a small variation of test_no_rtti such that the definition of polymorphic_derived1::get_key defintion is moved to a separate source and verify that it builds and runs correctly. If I define any other functions in the cpp file, I get a linker error saying that the get_key symbol is already defined. It looks to me that any serializable derived class must be completely defined in the header file. Is this correct? If so, why does such a limitation exist? I don't think this limitation exists Thank you Robert Ramey ------------------------------------------------------------------------------ _______________________________________________ Boost-users mailing list Boost-users@lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users