Subject: Re: [std-proposals] Allowing access to object representations
From: Krystian Stasiowski (sdkrystian_at_[hidden])
Date: 2019-08-21 13:55:42
Yes, you access the value of the object of the object, however, since its
not specified what exactly you get, it can be argued either way.
On Wed, Aug 21, 2019 at 2:49 PM language.lawyer--- via Std-Proposals <
> On 21/08/2019 21:44, Krystian Stasiowski via Std-Proposals wrote:
> > 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.
> And what you will be accessing is indeed "the object", not "the first
> element" of its object representation.
> > On Wed, Aug 21, 2019 at 2:05 PM language.lawyer--- via Std-Proposals <
> std-proposals_at_[hidden] <mailto:std-proposals_at_[hidden]>>
> > 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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