C23 status on cppreference

[Jakub Jelinek]

Hi!

https://en.cppreference.com/w/c/compiler_support
has a table with compiler support for C23.
I've added #embed and [[unsequenced]]/[[reproducible]] in there
yesterday, but am wondering about the accuracy of the rest.

Given the switch to -std=gnu23 preparation, I wonder what is still
unimplemented in GCC 15.
The cppreference page mentions as unimplemented on the GCC side
N2653 - Type change of u8 string literals
and as only partially implemented
N2341 - IEEE 754 decimal floating-point types
N2601 - IEEE 754 interchange and extended types
N2900 - Empty initializers
N2934 - New spelling of keywords
N3033 - __VA_OPT__
with following comments in the wiki source:
N2341: Only TR 24732 mentioned; some requirements in core language missing
N2601: Only TS 18661-3 mentioned; the status of conformance is unknown
N2900: missing support for scalars and VLAs

Are some of the papers/features known to be fully implemented (since which
version)?  E.g. for __VA_OPT__ I remember doing (and Jason too) various fixes
in the past few years, like PR89971, PR103415, PR101488.  Not really sure
what exactly C23 requires.

	Jakub