PATCH for expr.c

[Jason Merrill]

>>>>> Mark Mitchell <mark@markmitchell.com> writes:

>   struct Outer {
>     virtual ~Outer() {}
>   };

>   int
>   main()
>   {
>     { struct Inner : virtual public Outer {} inner; }
>     { struct Inner : virtual public Outer {} inner; }
>   }

> The deal is that during the constructing of one of the `inner'
> variables, the front-end creates a vtable in expand_upcast_fixups:
> It marks this vtable as having DECL_CONTEXT of `Inner'.

I think that's the problem.  I'll remove that; it shouldn't be necessary
anyway.

Jason