Re: [PATCH 2/9] lib/cmdline: Fix an invalid format specifier in an assertion msg

From: Guenter Roeck
Date: Wed Feb 21 2024 - 08:27:37 EST


On Wed, Feb 21, 2024 at 05:27:15PM +0800, David Gow wrote:
> The correct format specifier for p - n (both p and n are pointers) is
> %td, as the type should be ptrdiff_t.
>
> This was discovered by annotating KUnit assertion macros with gcc's
> printf specifier, but note that gcc incorrectly suggested a %d or %ld
> specifier (depending on the pointer size of the architecture being
> built).
>
> Fixes: 0ea09083116d ("lib/cmdline: Allow get_options() to take 0 to validate the input")
> Signed-off-by: David Gow <davidgow@xxxxxxxxxx>

Tested-by: Guenter Roeck <linux@xxxxxxxxxxxx>

> ---
> lib/cmdline_kunit.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/lib/cmdline_kunit.c b/lib/cmdline_kunit.c
> index d4572dbc9145..705b82736be0 100644
> --- a/lib/cmdline_kunit.c
> +++ b/lib/cmdline_kunit.c
> @@ -124,7 +124,7 @@ static void cmdline_do_one_range_test(struct kunit *test, const char *in,
> n, e[0], r[0]);
>
> p = memchr_inv(&r[1], 0, sizeof(r) - sizeof(r[0]));
> - KUNIT_EXPECT_PTR_EQ_MSG(test, p, NULL, "in test %u at %u out of bound", n, p - r);
> + KUNIT_EXPECT_PTR_EQ_MSG(test, p, NULL, "in test %u at %td out of bound", n, p - r);
> }
>
> static void cmdline_test_range(struct kunit *test)
> --
> 2.44.0.rc0.258.g7320e95886-goog
>