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.