Date: 2004-05-07 07:35:38
> I am trying to use the serialization library to save an object and a
> pointer to the object, but the pointer has the type of the object's
> base class.
> // declaration
> MyClass myObject; // object, not pointer
> MyBaseClass *myPointer = &myObject;
> // serialization code
> ar & BOOST_SERIALIZATION_NVP(myObject);
> ar & BOOST_SERIALIZATION_NVP(myPointer);
> I have also noticed that saving a pointer of the object's type
> pointing to the object solves the problem:
> So is it a bug, or have I done something wrong ?
This seems to be a bug in the current serialization library. I've
tracked it down to the fact that no basic_pointer_iserializer was
registered before the pointer to the derived class gets deserialized. As
far as I can tell a basic_pointer_iserializer only gets registered
when an object is loaded through a pointer. That's also why it works
when you additionally save a pointer to the object.
I managed to fix it in my local copy and got your sample application
to run with it successfully. The fix is straightforward. When
basic_archive_impl::load_object is called it not only needs to
register a basic_iserializer but also a basic_pointer_iserializer,
just as basic_archive_impl::load_pointer does. So I simply changed it
to also receive a basic_pointer_iserializer which is instantiated in
the load_non_pointer_type structure in iserializer.hpp. However, I'm
not sure if this is a good fix and so we'll have to wait what Robert
has to say about this.
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