Empty base optimization, sharing vptrs

[Jim Dehnert]

> > NONPOLYMORPHIC BASES
> >
> > We may allocate any number of empty base subobjects at the same  
> location
> > (the beginning of the complete object) except when, because of repeated 
> > inheritance, we'd have multiple subobjects of the same type  
> allocated in
> > the same place.
> 
> You probably have noticed that I currently don't read the standard  
> that way. But I also acknowledge that this is quite a reasonable way  
> of implementing things. Jason was supposed to send a message to  
> c++core regarding this issue. I did not receive this message, but  
> this might be a problem with our mail setup. Was the message sent?

SGI hasn't gotten it either.  I added an action item for Jason.
He now has an opportunity to be the first person to finish one :-).

-	    Jim Dehnert		dehnert at sgi.com
				(650)933-4272