On Sun, Feb 25, 2024 at 1:28 PM René Scharfe <l.s.r@xxxxxx> wrote:
> Am 25.02.24 um 19:05 schrieb Eric Sunshine:
> > On Sun, Feb 25, 2024 at 6:27 AM René Scharfe <l.s.r@xxxxxx> wrote:
> >> Getting the string size using sizeof only works in a macro and with a
> >> string constant, but that's exactly what we have and I don't see it
> >> changing anytime soon.
> >>
> >> /* Macro to test a character type */
> >> #define TEST_CTYPE_FUNC(func, string) \
> >
> > Taking into consideration the commit message warning about string
> > constants, would it make sense to update the comment to mention that
> > limitation?
> >
> > /* Test a character type. (Only use with string constants.) */
> > #define TEST_CTYPE_FUNC(func, string) \
> >> static void test_ctype_##func(void) { \
> >> for (int i = 0; i < 256; i++) { \
> >> + int expect = !!memchr(string, i, sizeof(string) - 1); \
>
> I think the temptation to pass a string pointer is low -- if only
> because there aren't any in this file. But adding such a warning
> can't hurt, so yeah, why not?
The patch just posted[1] by SZEDER reminded me that, on this project,
we assume that the compiler is smart enough to replace
`strlen("string-literal")` with the constant `15`, so rather than
worrying about updating comment to mention the sizeof() limitation,
you could perhaps just use `strlen(string)` instead of
`sizeof(string)-1`?
[1]: https://lore.kernel.org/git/20240225183452.1939334-1-szeder.dev@xxxxxxxxx/
