It's not impossible. For example, P0533R9 requires many changes to the C library.

On Sun, Oct 23, 2022 at 2:04 AM Thiago Macieira via Std-Proposals <> wrote:
On Saturday, 22 October 2022 03:35:59 PDT blacktea hamburger via Std-Proposals
> 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) - thiago (AT)
   Software Architect - Intel DCAI Cloud Engineering

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