Re: [PATCH] Documentation: Kunit: Fix example with compilation error

From: Maíra Canal
Date: Sat Jul 02 2022 - 09:35:34 EST


On 7/2/22 01:32, David Gow wrote:
> On Sat, Jul 2, 2022 at 2:17 AM Maíra Canal <mairacanal@xxxxxxxxxx> wrote:
>>
>> The Parameterized Testing example contains a compilation error, as the
>> signature for the description helper function should be void(*)(struct
>> sha1_test_case *, char *), so the struct should not be const. This is
>> warned by Clang:
>>
>> error: initialization of ‘void (*)(struct sha1_test_case *, char *)’
>> from incompatible pointer type ‘void (*)(const struct sha1_test_case *,
>> char *)’ [-Werror=incompatible-pointer-types]
>> 33 | KUNIT_ARRAY_PARAM(sha1, cases, case_to_desc);
>> | ^~~~~~~~~~~~
>> ../include/kunit/test.h:1339:70: note: in definition of macro
>> ‘KUNIT_ARRAY_PARAM’
>> 1339 | void (*__get_desc)(typeof(__next), char *) = get_desc; \
>>
>> Signed-off-by: Maíra Canal <mairacanal@xxxxxxxxxx>
>> ---
>
> Thanks for catching this. The change to the documentation looks good,
> but it may be better to change the array to be:
> const struct cases[] = { ... }

I missed that! Would you rather that I change it on a v2?

Best Regards,
- Maíra Canal

>
> That matches most of the existing uses of this, such as the mctp test,
> and encourages the use of const in cases (like the example) where it
> makes sense.
>
> I'm okay with it either way, though: they're both valid.
>
> Reviewed-by: David Gow <davidgow@xxxxxxxxxx>
>
> Cheers,
> -- David
>
>> Documentation/dev-tools/kunit/usage.rst | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/Documentation/dev-tools/kunit/usage.rst b/Documentation/dev-tools/kunit/usage.rst
>> index d62a04255c2e..8e72fb277058 100644
>> --- a/Documentation/dev-tools/kunit/usage.rst
>> +++ b/Documentation/dev-tools/kunit/usage.rst
>> @@ -517,7 +517,7 @@ By reusing the same ``cases`` array from above, we can write the test as a
>> };
>>
>> // Need a helper function to generate a name for each test case.
>> - static void case_to_desc(const struct sha1_test_case *t, char *desc)
>> + static void case_to_desc(struct sha1_test_case *t, char *desc)
>> {
>> strcpy(desc, t->str);
>> }
>> --
>> 2.36.1
>>
>> --