How intelligent is the garbage collector?

Hi all,
I've got a question about how garbage collection works in an ABAP objects context.
If there are no more references an object is cleaned up and the memory released. Fine.
What about an object O1, which in turn creates another object O2. O2 however also contains a refernce to O1.
When the original process completes, this leaves two objects that reference each other, but with no other contact to the 'outside world'. Is the garbage collector intelligent enough to dump them?
Any input appreciated,
Cheers
Mike

Hi,
Thanks for the feedback. I am still not sure - you say 'when the program ends it's part'. This is exactly the point - when the program ends, do the objects remain because they still contain references to each other?
More detail:
The references are public instance attributes of both objects (different classes). I would prefer to use functional methods, but am stuck with public attributes which I'm populating in the constructor.
So a process P declares a local var LV_O1 and does a CREATE OBJECT LV_O1.
In the constructor of O1, it does a
CREATE OBJECT me->ATTR_O2 to populate it's attribute with a reference to an instance of O2.
O2 doesn't need to do a CREATE OBJECT, but assigns a ref to O1 to it's attribute ATTR_O1.
So now O1 and O2 refer to each other by public attributes:
O1->ATTR_O2 and O2->ATTR_O1.
The big question is what happens when process P ends and it's variable LV_O1 ceases to exist?
In case anyone's wondering about the overall wisdom of the design, they have to be public attributes (used in Workflow) and they have to refer to each other as instantiation may also happen the other way around.
Cheers
Mike

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