[PATCH 0/3]: C++20 P0482R6 and C2X N2653: support for char8_t, mbrtoc8(), and c8rtomb().

[PATCH 0/3]: C++20 P0482R6 and C2X N2653: support for char8_t, mbrtoc8(), and c8rtomb().

[Tom Honermann]

This series of patches provides the following:
- A fix for bug 25744 [1].
- Implementations of the mbrtoc8 and c8rtomb functions adopted for
   C++20 via WG21 P0482R6 [2] and proposed for C2X in WG14 N2653 [3].
- A char8_t typedef as proposed for C2X in WG14 N2653 [3].

These patches addresses feedback provided in response to a previous 
submission [4][5].

Patch 1: A fix and test for bug 25744 [1].
Patch 2: Definitions of the mbrtoc8 and c8rtomb functions and the
          char8_t typedef.
Patch 3: Tests for the mbrtoc8 and c8rtomb functions and the char8_t
          typedef.

The fix for bug 25744 [1] is included in this patch series because the 
tests for mbrtoc8 and c8rtomb depend on it for exercising the special 
case where a pair of Unicode code points is converted to/from a single 
double byte sequence. Such conversion cases exist for Big5-HKSCS.

Since N2653 has not yet been adopted by WG14 for C2x, the new 
declarations are only present for C when _GNU_SOURCE is defined. If WG14 
adopts the proposal for C2x, additional changes will be needed to enable 
the changes for C2x.

Tom.

[1]: Bug 25744
      "mbrtowc with Big5-HKSCS returns 2 instead of 1 when consuming the
      second byte of certain double byte characters"
      https://sourceware.org/bugzilla/show_bug.cgi?id=25744

[2]: WG21 P0482R6
      "char8_t: A type for UTF-8 characters and strings (Revision 6)"
      https://wg21.link/p0482r6

[3]: WG14 N2653
      "char8_t: A type for UTF-8 characters and strings (Revision 1)"
      http://www.open-std.org/jtc1/sc22/wg14/www/docs/n2653.htm

[4]: "[PATCH 2/3]: C++20 P0482R6 and C2X N2653: Implement mbrtoc8,
      c8rtomb, char8_t"
      https://sourceware.org/pipermail/libc-alpha/2021-June/127232.html

[5]: "[PATCH 3/3]: C++20 P0482R6 and C2X N2653: Tests for mbrtoc8,
      c8rtomb, char8_t"
      https://sourceware.org/pipermail/libc-alpha/2021-June/127233.html

[PATCH 0/3]: C++20 P0482R6 and C2X N2653: support for char8_t, mbrtoc8(), and c8rtomb().

[Tom Honermann]

This series of patches provides the following:
- A fix for bug 25744 [1].
- Implementations of the mbrtoc8 and c8rtomb functions adopted for
   C++20 via WG21 P0482R6 [2] and for C2X via WG14 N2653 [3].
- A char8_t typedef as adopted for C2X via WG14 N2653 [3].

These patches addresses feedback provided in response to a previous 
submission [4].

Patch 1: A fix and test for bug 25744 [1].
Patch 2: Definitions of the mbrtoc8 and c8rtomb functions and the
          char8_t typedef.
Patch 3: Tests for the mbrtoc8 and c8rtomb functions and the char8_t
          typedef.

The fix for bug 25744 [1] is included in this patch series because the 
tests for mbrtoc8 and c8rtomb depend on it for exercising the special 
case where a pair of Unicode code points is converted to/from a single 
double byte sequence. Such conversion cases exist for Big5-HKSCS.

N2653 was adopted by WG14 for C2X during their recent meeting. This 
patch series enables the new declarations in C2X mode and when 
_GNU_SOURCE is defined.

Thank you to Joseph Myers and Carlos O'Donell for their prior reviews of 
this patch series.

Tom.

[1]: Bug 25744
      "mbrtowc with Big5-HKSCS returns 2 instead of 1 when consuming the
      second byte of certain double byte characters"
      https://sourceware.org/bugzilla/show_bug.cgi?id=25744

[2]: WG21 P0482R6
      "char8_t: A type for UTF-8 characters and strings (Revision 6)"
      https://wg21.link/p0482r6

[3]: WG14 N2653
      "char8_t: A type for UTF-8 characters and strings (Revision 1)"
      http://www.open-std.org/jtc1/sc22/wg14/www/docs/n2653.htm

[4]: "[PATCH 2/3]: C++20 P0482R6 and C2X N2653: Implement mbrtoc8,
      c8rtomb, char8_t"
      https://sourceware.org/pipermail/libc-alpha/2022-February/136558.html

Re: [PATCH 0/3]: C++20 P0482R6 and C2X N2653: support for char8_t, mbrtoc8(), and c8rtomb().

[Tom Honermann]

Is there anything I can do to help land this patch series? I believe all 
review comments have been addressed.

Tom.

On 2/27/22 11:53 AM, Tom Honermann via Libc-alpha wrote:
> This series of patches provides the following:
> - A fix for bug 25744 [1].
> - Implementations of the mbrtoc8 and c8rtomb functions adopted for
>   C++20 via WG21 P0482R6 [2] and for C2X via WG14 N2653 [3].
> - A char8_t typedef as adopted for C2X via WG14 N2653 [3].
>
> These patches addresses feedback provided in response to a previous 
> submission [4].
>
> Patch 1: A fix and test for bug 25744 [1].
> Patch 2: Definitions of the mbrtoc8 and c8rtomb functions and the
>          char8_t typedef.
> Patch 3: Tests for the mbrtoc8 and c8rtomb functions and the char8_t
>          typedef.
>
> The fix for bug 25744 [1] is included in this patch series because the 
> tests for mbrtoc8 and c8rtomb depend on it for exercising the special 
> case where a pair of Unicode code points is converted to/from a single 
> double byte sequence. Such conversion cases exist for Big5-HKSCS.
>
> N2653 was adopted by WG14 for C2X during their recent meeting. This 
> patch series enables the new declarations in C2X mode and when 
> _GNU_SOURCE is defined.
>
> Thank you to Joseph Myers and Carlos O'Donell for their prior reviews 
> of this patch series.
>
> Tom.
>
> [1]: Bug 25744
>      "mbrtowc with Big5-HKSCS returns 2 instead of 1 when consuming the
>      second byte of certain double byte characters"
>      https://sourceware.org/bugzilla/show_bug.cgi?id=25744
>
> [2]: WG21 P0482R6
>      "char8_t: A type for UTF-8 characters and strings (Revision 6)"
>      https://wg21.link/p0482r6
>
> [3]: WG14 N2653
>      "char8_t: A type for UTF-8 characters and strings (Revision 1)"
>      http://www.open-std.org/jtc1/sc22/wg14/www/docs/n2653.htm
>
> [4]: "[PATCH 2/3]: C++20 P0482R6 and C2X N2653: Implement mbrtoc8,
>      c8rtomb, char8_t"
> https://sourceware.org/pipermail/libc-alpha/2022-February/136558.html

Re: [PATCH 0/3]: C++20 P0482R6 and C2X N2653: support for char8_t, mbrtoc8(), and c8rtomb().

[Tom Honermann]

Ping. Could someone please assist me in landing these changes?

Tom.

On 3/23/22 11:32 AM, Tom Honermann via Libc-alpha wrote:
> Is there anything I can do to help land this patch series? I believe 
> all review comments have been addressed.
>
> Tom.
>
> On 2/27/22 11:53 AM, Tom Honermann via Libc-alpha wrote:
>> This series of patches provides the following:
>> - A fix for bug 25744 [1].
>> - Implementations of the mbrtoc8 and c8rtomb functions adopted for
>>   C++20 via WG21 P0482R6 [2] and for C2X via WG14 N2653 [3].
>> - A char8_t typedef as adopted for C2X via WG14 N2653 [3].
>>
>> These patches addresses feedback provided in response to a previous 
>> submission [4].
>>
>> Patch 1: A fix and test for bug 25744 [1].
>> Patch 2: Definitions of the mbrtoc8 and c8rtomb functions and the
>>          char8_t typedef.
>> Patch 3: Tests for the mbrtoc8 and c8rtomb functions and the char8_t
>>          typedef.
>>
>> The fix for bug 25744 [1] is included in this patch series because 
>> the tests for mbrtoc8 and c8rtomb depend on it for exercising the 
>> special case where a pair of Unicode code points is converted to/from 
>> a single double byte sequence. Such conversion cases exist for 
>> Big5-HKSCS.
>>
>> N2653 was adopted by WG14 for C2X during their recent meeting. This 
>> patch series enables the new declarations in C2X mode and when 
>> _GNU_SOURCE is defined.
>>
>> Thank you to Joseph Myers and Carlos O'Donell for their prior reviews 
>> of this patch series.
>>
>> Tom.
>>
>> [1]: Bug 25744
>>      "mbrtowc with Big5-HKSCS returns 2 instead of 1 when consuming the
>>      second byte of certain double byte characters"
>>      https://sourceware.org/bugzilla/show_bug.cgi?id=25744
>>
>> [2]: WG21 P0482R6
>>      "char8_t: A type for UTF-8 characters and strings (Revision 6)"
>>      https://wg21.link/p0482r6
>>
>> [3]: WG14 N2653
>>      "char8_t: A type for UTF-8 characters and strings (Revision 1)"
>>      http://www.open-std.org/jtc1/sc22/wg14/www/docs/n2653.htm
>>
>> [4]: "[PATCH 2/3]: C++20 P0482R6 and C2X N2653: Implement mbrtoc8,
>>      c8rtomb, char8_t"
>> https://sourceware.org/pipermail/libc-alpha/2022-February/136558.html

[PATCH 0/3]: C++20 P0482R6 and C2X N2653: support for char8_t, mbrtoc8(), and c8rtomb().

[Tom Honermann]

This series of patches provides the following:
- A fix for bug 25744 [1].
- Implementations of the mbrtoc8 and c8rtomb functions adopted for
   C++20 via WG21 P0482R6 [2] and proposed for C2X in WG14 N2653 [3].
- A char8_t typedef as proposed for C2X in WG14 N2653 [3].
- A _CHAR8_T_SOURCE feature test macro to be used to opt-in to support
   for the char8_t typedef and mbrtoc8/c8rtomb functions in pre-C++20
   or C source code.

Patch 1: A fix and test for bug 25744 [1].
Patch 2: Definitions of the mbrtoc8 and c8rtomb functions, the char8_t
          typedef, and the _CHAR8_T_SOURCE feature test macro.
Patch 3: Tests for the mbrtoc8 and c8rtomb functions and the char8_t
          typedef.

The fix for bug 25744 [1] is included in this patch series because the 
tests for mbrtoc8 and c8rtomb depend on it for exercising the special 
case where a pair of Unicode code points is converted to/from a single 
double byte sequence.  Such conversion cases exist for Big5-HKSCS.

Tom.

[1]: Bug 25744
      "mbrtowc with Big5-HKSCS returns 2 instead of 1 when consuming the
      second byte of certain double byte characters"
      https://sourceware.org/bugzilla/show_bug.cgi?id=25744

[2]: WG21 P0482R6
      "char8_t: A type for UTF-8 characters and strings (Revision 6)"
      https://wg21.link/p0482r6

[3]: WG14 N2653
      "char8_t: A type for UTF-8 characters and strings (Revision 1)"
      http://www.open-std.org/jtc1/sc22/wg14/www/docs/n2653.htm