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From: Thiago Adams <thiago.adams@gmail.com>
Newsgroups: comp.lang.c
Subject: Re: C23 thoughts and opinions
Date: Thu, 6 Jun 2024 15:01:46 -0300
Organization: A noiseless patient Spider
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On 25/05/2024 08:19, Thiago Adams wrote:

....

> In my view , for this sample constexpr generates noise. It also can make 
> the compilation slower, otherwise, why not everything constexpr by defaul?
> I still didn't find a useful usage for constexpr that would compensate 
> the mess created with const, constexpr. I already saw ( I don't have it 
> now ) proposals to make const more like constexpr in C. In C++ const is 
> already a constant expression!
> The justification for C was VLA. They should consider VLA not VLA if it 
> has a constant expression. In other words, better break this than create 
> a mess.
> #define makes the job of constexpr.
> 
> 
> 

One more sample of NOISE of constexpr from the same real source.


int compare(const Node* a, const Node* b)
{
     return memcmp(a, b, sizeof(Node)) == 0;
}

bool IsValid(Node * pnid)
{
     static constexpr Node node = { 1, 2 };
     return compare(pnid, &node);
}

What is expectation passing the address of compile constant to a runtime 
function? This is pure noise!
Nothing happens, nothing is done at compile time.

https://godbolt.org/z/ecsMf4vaY