C++ Logo


Advanced search

Subject: Re: [std-proposals] Allowing access to object representations
From: sdkrystian (sdkrystian_at_[hidden])
Date: 2019-08-21 14:26:12

I thought about it for a bit, and C++ really has no concept of value truncation, so you get a prvalue of type char that stores the entire value of the object into it's context. Therefore, strictly following the rules of the abstract machine:int a = 42;auto b = reinterpret_cast<unsigned char*>(&a);int c = *b; // this will have the value 42(language-lawyer fact check me on this one)Sent from my Samsung Galaxy smartphone.
-------- Original message --------From: Timur Doumler via Std-Proposals <std-proposals_at_[hidden]> Date: 8/21/19 15:11 (GMT-05:00) To: std-proposals_at_[hidden] Cc: Timur Doumler <cpp_at_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_at_[hidden]> 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.> -- > Std-Proposals mailing list> Std-Proposals_at_[hidden]> https://lists.isocpp.org/mailman/listinfo.cgi/std-proposals-- Std-Proposals mailing listStd-Proposals_at_[hidden]https://lists.isocpp.org/mailman/listinfo.cgi/std-proposals

STD-PROPOSALS list run by std-proposals-owner@lists.isocpp.org

Standard Proposals Archives on Google Groups