On 2/28/22 6:01 PM, Joseph Myers wrote:
> On Sun, 27 Feb 2022, Tom Honermann via Libc-alpha wrote:
>
>> This patch provides implementations for the mbrtoc8 and c8rtomb functions
>> adopted for C++20 via WG21 P0482R6 [1] and for C2X via WG14 N2653 [2]. It also
>> provides the char8_t typedef adopted for C2X via WG14 N2653 [2].
>>
>> The mbrtoc8 and c8rtomb functions are declared in uchar.h in C2X mode or when
>> the _GNU_SOURCE macro or C++20 __cpp_char8_t feature test macro is defined.
>>
>> The char8_t typedef is declared in uchar.h in C2X mode or when the _GNU_SOURCE
>> macro is defined and the C++20 __cpp_char8_t feature test macro is not defined
>> (if __cpp_char8_t is defined, then char8_t is a builtin type).
> You should almost never have "defined __USE_GNU || ..." in header
> conditionals, because _GNU_SOURCE implies the other feature test macros.

Ah, right. Thank you, a corrected patch is attached.

Tom.