VTTs, yet again

[Jim Dehnert]

> From: Mark Mitchell <mark at codesourcery.com>
> 
> The description of the VTT (in VTT order) doesn't specify which vptrs
> point into the main vtable group and which into construction vtable
> groups.  It should.

I don't think it needs to.  The VTT is the interface, and we describe
how it is used.  You are free to make a construction vtable for every
subobject if you like -- it will just be often suboptimal.

> I think the rule is:
> 
>   o If this VTT is a primary VTT, then the primary and secondary
>     vptrs point into the main vtable group.
> 
>   o Otherwise, this VTT is a secondary VTT for a base B that itself
>     uses virtual bases.  In that case, use vptrs that point into the
>     construction vtable for B-in-D.
> 
> Right?

That sounds right to me, but you could move all the first set into the
second set without being incorrect -- just suboptimal.

Jim

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