Datatype::copy(origin_addr, origin_count, origin_datatype, recv_addr, target_count, target_datatype);
if(request!=nullptr)
*request = MPI_REQUEST_NULL;
Datatype::copy(origin_addr, origin_count, origin_datatype, recv_addr, target_count, target_datatype);
if(request!=nullptr)
*request = MPI_REQUEST_NULL;