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Re: [std-proposals] [[unevaluated]]

From: Jonathan Wakely <cxx_at_[hidden]>
Date: Wed, 20 May 2026 20:45:01 +0100
On Wed, 20 May 2026, 20:19 Marcin Jaczewski, <marcinjaczewski86_at_[hidden]>
wrote:

> śr., 20 maj 2026 o 08:45 Jonathan Wakely via Std-Proposals
> <std-proposals_at_[hidden]> napisał(a):
> >
> >
> >
> > On Wed, 20 May 2026, 07:15 Frederick Virchanza Gotham via Std-Proposals,
> <std-proposals_at_[hidden]> wrote:
> >>
> >>
> >>
> >> On Tuesday, May 19, 2026, Jonathan Wakely wrote:
> >>>
> >>>
> >>>
> >>>>
> >>>> But I think we'd be better off with an attribute that tells the
> compiler exactly what we have in mind. And of course the attribute would
> ensure that the function is not emitted in the object file.
> >>>
> >>>
> >>> You get that with consteval.
> >>
> >>
> >>
> >>
> >> Inside the body of a consteval function, if you make a call to a
> non-constexpr function, you get a compiler warning.
> >>
> >> Also if you were to invoke 'optional::operator*' before invoking
> 'optional::has_value', you might get a warning (e.g. from cppcheck).
> >>
> >> To cut down on warnings, and to ensure that the function actually never
> gets invoked -- not even in a consteval context at compile time -- it would
> be better to tell the compiler (and also tell cppcheck) that the function
> is [[unevaluated]]. And if someone tries to take its address or invoke it,
> I would like this to be an error rather than a warning.
> >
> >
> >
> > You "forgot" to reply to the part where I asked for motivation. No
> change there then.
> >
>
> One question, did he even once answer a question like this?
> And you expect this will be this time when he makes proposals that
> have real motivation?
>

I don't think so.


> For some time I have not even read his post as they do not contribute
> anything there,
> only replies from people like you have some value here. But I start
> doubting that all
> the effort you put into trying to salvage any meaningful ideas from
> this discussion is worth your time.
>

It's been clear for years that he has no intention of doing anything except
wasting this list's time, and people are too tolerant of it IMHO.

Received on 2026-05-20 19:45:17