It's not impossible. For example, P0533R9 <https://wg21.link/P0533R9>
requires many changes to the C library.

On Sun, Oct 23, 2022 at 2:04 AM Thiago Macieira via Std-Proposals <
std-proposals_at_[hidden]> wrote:

> On Saturday, 22 October 2022 03:35:59 PDT blacktea hamburger via
> Std-Proposals
> wrote:
> > WG21's views are not necessarily the same as WG14. It may broke some
> code,
> > but it was probably code of the sort that has become increasingly rare
> over
> > the years since C++ diverged from C. C and C++ are different languages,
> > aren't they?
> >
> > So I think it can be still proposed to WG21.
>
> Not exactly.
>
> On all operating systems except for Windows, the C library comes from the
> OS
> and the C++ library comes with the compiler, so they are separate
> implementations and have limitations on what the C++ standard can
> influence on
> the C library, even the <cxxxx> headers.
>
> So this change needs to take into account the difficulty in implementing
> it and
> evaluate whether it's worth the effort.
>
> --
> Thiago Macieira - thiago (AT) macieira.info - thiago (AT) kde.org
> Software Architect - Intel DCAI Cloud Engineering
>
>
>
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