Hello, I've just started to try using Boost.MPI, but I'm facing problems with user-defined class serialization. Maybe I'm just missing something. Basically, I have a pure virtual class "task" with the method execute and I want to send classes that implement this interface through MPI. For this to work, I have to register derived class for serialization. Unfortunately, this causes compilation error under MSVC9.0. Here is my code : #include <iostream> #include <exception> #include #include #include class task { public: virtual void execute() = 0; }; class dtask : public task { public: dtask() {} dtask(std::string text) : text(text) {} virtual void execute() { std::cout << text << std::endl; } private: std::string text; friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int version) { ar & text; } }; BOOST_CLASS_EXPORT(dtask) int main(int argc, char* argv[]) { boost::mpi::environment env(argc, argv); boost::mpi::communicator world; try { if (world.rank() == 0) { task * t = new dtask("Blah"); world.send(1, 0, t); } else if (world.rank() == 1) { task * t; world.recv(0, 0, t); t->execute(); } } catch (std::exception &e) { std::cout << "Error : " << e.what() << std::endl; } return 0; } And the compilation error : 1>Compiling... 1>data_testbed.cpp 1>d:\grooviz\libs\boost_1_38\boost\mpi\datatype.hpp(184) : error C2664: 'boost::mpl::assertion_failed' : cannot convert parameter 1 from 'boost::mpl::failed ************boost::mpi::is_mpi_datatype<T>::* ***********' to 'boost::mpl::assert<false>::type' 1> with 1> [ 1> T=std::basic_string 1> ] 1> No constructor could take the source type, or constructor overload resolution was ambiguous 1> d:\grooviz\libs\boost_1_38\boost\mpi\detail\mpi_datatype_primitive.hpp(96) : see reference to function template instantiation 'MPI_Datatype boost::mpi::get_mpi_datatype<T>(const T &)' being compiled 1> with 1> [ 1> T=std::string 1> ] 1> d:\grooviz\libs\boost_1_38\boost\archive\detail\oserializer.hpp(95) : see reference to function template instantiation 'void boost::mpi::detail::mpi_datatype_primitive::save<T>(const T &)' being compiled 1> with 1> [ 1> T=std::string 1> ] 1> d:\grooviz\libs\boost_1_38\boost\archive\detail\oserializer.hpp(212) : see reference to function template instantiation 'void boost::archive::save_access::save_primitive(Archive &,const T &)' being compiled 1> with 1> [ 1> Archive=boost::mpi::detail::content_oarchive, 1> T=std::string 1> ] 1> d:\grooviz\libs\boost_1_38\boost\archive\detail\oserializer.hpp(211) : while compiling class template member function 'void boost::archive::detail::save_non_pointer_type::save_primitive::invoke(Archive &,const T &)' 1> with 1> [ 1> Archive=boost::mpi::detail::content_oarchive, 1> T=std::string 1> ] 1> d:\grooviz\libs\boost_1_38\boost\archive\detail\oserializer.hpp(294) : see reference to class template instantiation 'boost::archive::detail::save_non_pointer_type::save_primitive' being compiled 1> with 1> [ 1> Archive=boost::mpi::detail::content_oarchive, 1> T=std::string 1> ] 1> d:\grooviz\libs\boost_1_38\boost\archive\detail\oserializer.hpp(282) : while compiling class template member function 'void boost::archive::detail::save_non_pointer_type::invoke(Archive &,const T &)' 1> with 1> [ 1> Archive=boost::mpi::detail::content_oarchive, 1> T=std::string 1> ] 1> d:\grooviz\libs\boost_1_38\boost\archive\detail\oserializer.hpp(506) : see reference to class template instantiation 'boost::archive::detail::save_non_pointer_type' being compiled 1> with 1> [ 1> Archive=boost::mpi::detail::content_oarchive, 1> T=std::string 1> ] 1> d:\grooviz\libs\boost_1_38\boost\mpi\detail\ignore_skeleton_oarchive.hpp(46) : see reference to function template instantiation 'void boost::archive::save(Archive &,const T &)' being compiled 1> with 1> [ 1> Archive=boost::mpi::detail::content_oarchive, 1> T=std::string 1> ] 1> d:\grooviz\libs\boost_1_38\boost\archive\detail\interface_oarchive.hpp(64) : see reference to function template instantiation 'void boost::mpi::detail::ignore_skeleton_oarchive<Archive>::save_override<const T>(const T &,int)' being compiled 1> with 1> [ 1> Archive=boost::mpi::detail::content_oarchive, 1> T=std::string 1> ] 1> d:\grooviz\libs\boost_1_38\boost\archive\detail\interface_oarchive.hpp(72) : see reference to function template instantiation 'Archive &boost::archive::detail::interface_oarchive<Archive>::operator <<<const T>(T &)' being compiled 1> with 1> [ 1> Archive=boost::mpi::detail::content_oarchive, 1> T=std::string 1> ] 1> d:\grooviz\sandbox\test\data_testbed\data_testbed.cpp(30) : see reference to function template instantiation 'Archive &boost::archive::detail::interface_oarchive<Archive>::operator &std::string(T &)' being compiled 1> with 1> [ 1> Archive=boost::mpi::detail::content_oarchive, 1> T=std::string 1> ] 1> d:\grooviz\libs\boost_1_38\boost\serialization\access.hpp(109) : see reference to function template instantiation 'void dtask::serialize<Archive>(Archive &,const unsigned int)' being compiled 1> with 1> [ 1> Archive=boost::mpi::detail::ignore_skeleton_oarchiveboost::mpi::detail::content_oarchive 1> ] 1> d:\grooviz\libs\boost_1_38\boost\serialization\serialization.hpp(74) : see reference to function template instantiation 'void boost::serialization::access::serialize(Archive &,T &,const unsigned int)' being compiled 1> with 1> [ 1> Archive=boost::mpi::detail::ignore_skeleton_oarchiveboost::mpi::detail::content_oarchive, 1> T=dtask 1> ] 1> d:\grooviz\libs\boost_1_38\boost\serialization\serialization.hpp(133) : see reference to function template instantiation 'void boost::serialization::serialize(Archive &,T &,const unsigned int)' being compiled 1> with 1> [ 1> Archive=boost::mpi::detail::ignore_skeleton_oarchiveboost::mpi::detail::content_oarchive, 1> T=dtask 1> ] 1> d:\grooviz\libs\boost_1_38\boost\archive\detail\oserializer.hpp(148) : see reference to function template instantiation 'void boost::serialization::serialize_adl(Archive &,T &,const unsigned int)' being compiled 1> with 1> [ 1> Archive=boost::mpi::detail::ignore_skeleton_oarchiveboost::mpi::detail::content_oarchive, 1> T=dtask 1> ] 1> d:\grooviz\libs\boost_1_38\boost\archive\detail\oserializer.hpp(140) : while compiling class template member function 'void boost::archive::detail::oserializer::save_object_data(boost::archive::detail::basic_oarchive &,const void *) const' 1> with 1> [ 1> Archive=boost::mpi::detail::ignore_skeleton_oarchiveboost::mpi::detail::content_oarchive, 1> T=dtask 1> ] 1> d:\grooviz\libs\boost_1_38\boost\archive\detail\oserializer.hpp(170) : see reference to class template instantiation 'boost::archive::detail::oserializer' being compiled 1> with 1> [ 1> Archive=boost::mpi::detail::ignore_skeleton_oarchiveboost::mpi::detail::content_oarchive, 1> T=dtask 1> ] 1> d:\grooviz\libs\boost_1_38\boost\archive\detail\oserializer.hpp(167) : while compiling class template member function 'const boost::archive::detail::basic_oserializer &boost::archive::detail::pointer_oserializer::get_basic_serializer(void) const' 1> with 1> [ 1> Archive=boost::mpi::detail::ignore_skeleton_oarchiveboost::mpi::detail::content_oarchive, 1> T=dtask 1> ] 1> d:\grooviz\libs\boost_1_38\boost\serialization\export.hpp(75) : see reference to class template instantiation 'boost::archive::detail::pointer_oserializer' being compiled 1> with 1> [ 1> Archive=boost::mpi::detail::ignore_skeleton_oarchiveboost::mpi::detail::content_oarchive, 1> T=dtask 1> ] 1> d:\grooviz\libs\boost_1_38\boost\serialization\export.hpp(72) : while compiling class template member function 'const boost::archive::detail::basic_pointer_oserializer &boost::archive::detail::export_impl::enable_save(boost::mpl::true_)' 1> with 1> [ 1> Archive=boost::mpi::detail::ignore_skeleton_oarchiveboost::mpi::detail::content_oarchive, 1> Serializable=dtask 1> ] 1> d:\grooviz\libs\boost_1_38\boost\serialization\export.hpp(106) : see reference to class template instantiation 'boost::archive::detail::export_impl' being compiled 1> with 1> [ 1> Archive=boost::mpi::detail::ignore_skeleton_oarchiveboost::mpi::detail::content_oarchive, 1> Serializable=dtask 1> ] 1> d:\grooviz\libs\boost_1_38\boost\serialization\export.hpp(105) : while compiling class template member function 'void boost::archive::detail::ptr_serialization_support::instantiate(void)' 1> with 1> [ 1> Archive=boost::mpi::detail::ignore_skeleton_oarchiveboost::mpi::detail::content_oarchive, 1> Serializable=dtask 1> ] 1> d:\grooviz\libs\boost_1_38\boost\archive\detail\register_archive.hpp(27) : see reference to class template instantiation 'boost::archive::detail::ptr_serialization_support' being compiled 1> with 1> [ 1> Archive=boost::mpi::detail::ignore_skeleton_oarchiveboost::mpi::detail::content_oarchive, 1> Serializable=dtask 1> ] 1> d:\grooviz\libs\boost_1_38\boost\serialization\export.hpp(128) : see reference to class template instantiation 'boost::archive::detail::_ptr_serialization_support' being compiled 1> with 1> [ 1> Archive=boost::mpi::detail::ignore_skeleton_oarchiveboost::mpi::detail::content_oarchive, 1> Serializable=dtask 1> ] 1> d:\grooviz\libs\boost_1_38\boost\serialization\export.hpp(124) : while compiling class template member function 'const boost::archive::detail::guid_initializer<T> &boost::archive::detail::guid_initializer<T>::export_guid(const char *,boost::mpl::false_)' 1> with 1> [ 1> T=dtask 1> ] 1> d:\grooviz\sandbox\test\data_testbed\data_testbed.cpp(36) : see reference to class template instantiation 'boost::archive::detail::guid_initializer<T>' being compiled 1> with 1> [ 1> T=dtask 1> ] Note that if I remove the BOOST_CLASS_EXPORT(dtask), the program compiles fine but I get "unregistered class" exception at runtime. Note also that if I use dtask pointer instead of task with send and recv, the program runs fine. Additionaly, if I use primitive type like "int" instead of std::string in my derived class, the compilation goes fine with the export statement. It seems to me that at some point the compiler tries to get the MPI datatype of std::string even if it shouldn't since it's not a primitive type. What am I missing here ? Thank you in advance, Ariel Ouziel