Re: [boost] aligned_storage in unions

Subject: Re: [boost] aligned_storage in unions
From: Frank Mori Hess (frank.hess_at_[hidden])
Date: 2010-09-22 14:38:16

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On Wednesday 22 September 2010, Larry Evans wrote:
> On 09/22/10 13:00, Frank Mori Hess wrote:
> > On Wednesday 22 September 2010, Larry Evans wrote:
> >>   Strict aliasing is an assumption, made by the C (or C++) compiler,
> >>   that dereferencing pointers to objects of different types will
> >>   never refer to the same memory location (i.e. alias each other.)
> >>
> >> Could you point to the variant code violating this rule?
> >
> > How about if you re-assign a variant to a different type.  Won't it
> > re-use the same in-place storage for a different type?
>
> Yes, AFAICT.  Thanks.
>
> So now my other question: how can C++0x avoid this?

I think it would be because C++0x allows non-pod types in unions.

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