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

On Mon, 15 Nov 2021 at 07:30, Junio C Hamano [off-list ref] 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.

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.

Martin