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Subject: Re: [std-proposals] Allowing access to object representations
From: Krystian Stasiowski (sdkrystian_at_[hidden])
Date: 2019-08-21 13:44:07


Yes, you can. If the pointer value is unchanged, then it still points to
the original object, and since the resulting pointer is of, say, char,
unsigned char, or std::byte, the strict aliasing rules allow you to access
the object.

On Wed, Aug 21, 2019 at 2:05 PM language.lawyer--- via Std-Proposals <
std-proposals_at_[hidden]> wrote:

> On 21/08/2019 11:22, sdkrystian via Std-Proposals wrote:
> > Using reinterpret_cast, you can access the first element, but thats
> about it (pointer arithmetic is UB)
>
> No, u can't access "the first element".
> reinterpret_cast won't change the pointer value, the result of
> reinterpret_cast "points to" the same object to which the argument of
> reinterpret_cast pointed to.
> Indirection through such a pointer yields an lvalue denoting the object to
> which pointer points to and this influences lvalue-to-rvalue conversion
> applied to (or assignment through) this lvalue in a funny way.
> --
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> Std-Proposals_at_[hidden]
> https://lists.isocpp.org/mailman/listinfo.cgi/std-proposals
>



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