HP's object layout, clarification

[Jason Merrill]

Your reasoning would also suggest that compilers can't have base and
derived classes at the same address, since they are not the "same object".
When you're dealing with void*, the idea of what object a void pointer
points to is a bit vague.

I think it's pretty clear that the committee's intent was to allow empty
bases to overlap except when they are of the same type.  Perhaps the
language in the standard could be clarified a bit.

Jason