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Subject: Re: [std-proposals] Allowing access to object representations
From: Timur Doumler (cpp_at_[hidden])
Date: 2019-08-21 13:09:38


Ok, so what is then, formally, the semantics of dereferencing a reinterpret_cast<char*>(&some_object); and is this defined behaviour?

Cheers,
Timur

> On 21 Aug 2019, at 20:05, 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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