For an object of class type, what would the range of representable values be? For example:
struct S { int a, b, c, d; };
void f()
{
S a{};
char b = *reinterpret_cast<char*>(&a); // cast leaves value unchanged, range of representable values for an object of type S is logically greater than char, but what wording specifies that?
}
Sent from my Samsung Galaxy smartphone.
-------- Original message --------
From: "language.lawyer--- via Std-Proposals" <std-proposals@lists.isocpp.org>
Date: 8/21/19 15:32 (GMT-05:00)
To: std-proposals@lists.isocpp.org
Cc: language.lawyer@gmail.com
Subject: Re: [std-proposals] Allowing access to object representations
> The example I provided is not the best, since 42 is small enough for unsigned char and int to work as expected, imagine that I wrote a bigger number, such as 1000
This is covered by http://eel.is/c++draft/expr.pre#4
> Sent from my Samsung Galaxy smartphone.
>
> -------- Original message --------
> From: Timur Doumler via Std-Proposals <std-proposals@lists.isocpp.org>
> Date: 8/21/19 15:11 (GMT-05:00)
> To: std-proposals@lists.isocpp.org
> Cc: Timur Doumler <cpp@timur.audio>
> Subject: Re: [std-proposals] Allowing access to object representations
>
> This doesn't make sense to me. If I have an object of type int (or, say, a struct containing an int), then the value has 4 bytes. If I access that value by dereferencing a char pointer that aliases that object, all I can ever get from that char is a single byte. How can this be "the object"?
>
> Cheers,
> Timur
>
> > On 21 Aug 2019, at 20:59, language.lawyer--- via Std-Proposals <std-proposals@lists.isocpp.org> wrote:
> >
> >> On 21/08/2019 21:55, Krystian Stasiowski via Std-Proposals wrote:
> >> Yes, you access the value of the object of the object, however, since its not specified what exactly you get
> >
> > It is specified: you get the value contained in the object.
> >
> >> http://eel.is/c++draft/conv.lval#3.4
> >
> > Indeed, it is specified here.
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