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Re: [PATCH] revision: use C99 declaration of variable in for() loop

From
Junio C Hamano <gitster@pobox.com>
Date
Nov 16, 2021, 08:29 UTC
Message-ID
<xmqqee7gbj1n.fsf@gitster.g>
In-Reply-To
<CAN0heSpLy8c6WM1UpyEXJLfmnX=5B0eFhJwH3wqSZN15HAJGeg@mail.gmail.com>
Martin Ågren <martin.agren@gmail.com> writes:
Show 23 quoted lines
> On Mon, 15 Nov 2021 at 07:30, Junio C Hamano <gitster@pobox.com> wrote:
>>
>> There are certain C99 features that might be nice to use in our code
>> base, but we've hesitated to do so in order to avoid breaking
>> compatibility with older compilers. But we don't actually know if
>> people are even using pre-C99 compilers these days.
>
>> is a long-enough time, so let's try it agin.
>
> s/agin/again/
>
>>  void show_object_with_name(FILE *out, struct object *obj, const char *name)
>>  {
>> -       const char *p;
>> -
>>         fprintf(out, "%s ", oid_to_hex(&obj->oid));
>> -       for (p = name; *p && *p != '\n'; p++)
>> +       for (const char *p = name; *p && *p != '\n'; p++)
>>                 fputc(*p, out);
>>         fputc('\n', out);
>>  }
>
> This seems like a stable-enough function for this experiment.

Yup, the callers and the implementation are from several years ago, if I am not mistaken.

Show 12 quoted lines
> Similar to 765dc16888 ("git-compat-util: always enable variadic macros",
> 2021-01-28), maybe we should add something like
>
>   /*
>    * This "for (const char *p = ..." is made as a first step towards
>    * making use of such declarations elsewhere in our codebase.  If
>    * it causes compilation problems on your platform, please report
>    * it to the Git mailing list at git@vger.kernel.org.
>    */
>
> to reduce the chance of someone patching it up locally thinking that
> it's just a one-off.

Probably. It would help people to refrain from copying and pasting this and making it harder to back out, too.

Previous: Martin ÅgrenNext: brian m. carlson
Message 13 of 22 in “MyFirstContribution.txt: fix undeclared variable i in sample code”
  1. MyFirstContribution.txt: fix undeclared variable i in sample codeSaksham Mittal, Nov 13, 2021
  2. Johannes AltmanningerNov 13, 2021
  3. Saksham MittalNov 13, 2021
  4. Junio C HamanoNov 14, 2021
  5. Is 'for (int i = [...]' bad for C STD compliance reasons? (was: [PATCH] MyFirstContribution.txt: fix undeclared variable i in sample code)Ævar Arnfjörð Bjarmason, Nov 14, 2021
  6. Junio C HamanoNov 14, 2021
  7. Ævar Arnfjörð BjarmasonNov 14, 2021
  8. Carlo ArenasNov 14, 2021
  9. brian m. carlsonNov 14, 2021
  10. Carlo ArenasNov 14, 2021
  11. revision: use C99 declaration of variable in for() loopJunio C Hamano, Nov 15, 2021
  12. Martin ÅgrenNov 15, 2021
  13. Junio C HamanoNov 16, 2021
  14. brian m. carlsonNov 15, 2021
  15. Phillip WoodNov 17, 2021
  16. Ævar Arnfjörð BjarmasonNov 17, 2021
  17. SZEDER GáborNov 17, 2021
  18. Junio C HamanoNov 18, 2021
  19. Phillip WoodDec 7, 2021
  20. Junio C HamanoDec 7, 2021
  21. Removing -Wdeclaration-after-statement (was: [PATCH] revision: use C99 declaration of variable in for() loop)Ævar Arnfjörð Bjarmason, Dec 8, 2021
  22. Junio C HamanoDec 8, 2021

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