Hello I'm having a bit of trouble with something and I was hoping someone would be able to help me out. I'm using boost interprocess. Here's what I have: class Animal { ... code removed... } class Dog : public Animal { ... code removed... } class Cat : public Animal { ... code removed... } typedef boost::interprocess::allocator, managed_shared_memory::segment_manager> ShmemAllocator; typedef vector, ShmemAllocator> MyVector; int main(int argc, char * const argv[]) { ..code removed.. managed_shared_memory segment(create_only, "MySharedMemory", 65536); const ShmemAllocator alloc_inst(segment.get_segment_manager()); MyVector *myVector = segment.construct<MyVector>("MyVector")(alloc_inst); intrusive_ptr dogPtr(segment.construct<Dog>("DogPtr")()); myVector->push_back(dogPtr); The myVector->push_back(dogPtr) line gives the following error: error: no matching function for call to 'boost::container::vector, boost::interprocess::allocator, boost::interprocess::segment_manager, boost::interprocess::iset_index> > >::push_back(boost::interprocess::intrusive_ptr&)' I have been unable to get this to work. Can someone please tell me how to get my dogPtr into my Animal array? I was able to get it to work like this: intrusive_ptr animalPtr(dynamic_pointer_cast<Animal>(dogPtr.get())); myVector->push_back(animalPtr); But that's kind of ugly, creating a new variable and all. I'm hoping I don't have to do that. Many thanks