Empty base optimization, sharing vptrs

[Matt Austern]

On Jun 16,  5:26pm, Jim Dehnert wrote:

> > 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 :-).

Jason did send the message, and there has been a discussion about this
issue on c++std-core.  Jason's message was c++std-core-8101.

My take on the discussion is that everyone agrees there is a defect in
the standard, because it can reasonably be interpreted both ways, and that
the standard needs to be clarified.  Several people expressed support for
the interpretation under which this proposed layout rule is legal.  My
guess (perhaps Mike and Jason could comment, since they've both seen the
discussion too) is that's how this issue will eventually be resolve.

			--Matt