Draft C2Y _BitInt related proposals

[Florian Weimer]

* Jakub Jelinek via Gcc:

> As I wrote earlier, I'd like to see _BitInt I/O support in
> *printf*/*scanf* and extending support of _BitInt in stdbit.h
> in C2Y.
>
> For those I wrote drafts of possible C2Y papers:
> https://jakubjelinek.github.io/wg14/va_arg_bitint.html
> https://jakubjelinek.github.io/wg14/stdbit_bitint.html
>
> I'd appreciate any comments on this.

Is this going in the right direction, though?

Why shouldn't programmers be able to write %d in the format string and
print _BitInt arguments this way?

I think it's time to pass a type descriptor for varags functions.  Then
it wouldn't be necessary to pass the _BitInt size as argument to
va_arg_bitint.

Thanks,
Florian