[PATCH RESEND v2] Documentation: KUnit: Fix example with compilation error

[PATCH RESEND v2] Documentation: KUnit: Fix example with compilation error

[Maíra Canal]

The Parameterized Testing example contains a compilation error, as the
signature for the description helper function is void(*)(const struct
sha1_test_case *, char *), and the struct is non-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@riseup.net>
---
v1 -> v2: https://lore.kernel.org/linux-kselftest/CABVgOSkFKJBNt-AsWmOh2Oni4QO2xdiXJiYD1EVcS-Qz=BjJRw@mail.gmail.com/T/#mf546fc75bf9e5bd27cb3bbd531b51409fbc87a9d
- Instead of changing the function signature to non-const, makes the cases
const (David Gow).
---
 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..44158eecb51e 100644
--- a/Documentation/dev-tools/kunit/usage.rst
+++ b/Documentation/dev-tools/kunit/usage.rst
@@ -505,7 +505,7 @@ By reusing the same ``cases`` array from above, we can write the test as a
 		const char *str;
 		const char *sha1;
 	};
-	struct sha1_test_case cases[] = {
+	const struct sha1_test_case cases[] = {
 		{
 			.str = "hello world",
 			.sha1 = "2aae6c35c94fcfb415dbe95f408b9ce91ee846ed",
-- 
2.36.1

Re: [PATCH RESEND v2] Documentation: KUnit: Fix example with compilation error

[Daniel Latypov]

On Wed, Jul 20, 2022 at 11:57 AM Maíra Canal <mairacanal@riseup.net> wrote:
>
> The Parameterized Testing example contains a compilation error, as the
> signature for the description helper function is void(*)(const struct
> sha1_test_case *, char *), and the struct is non-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@riseup.net>

Reviewed-by: Daniel Latypov <dlatypov@google.com>

Thanks for fixing this!

Re: [PATCH RESEND v2] Documentation: KUnit: Fix example with compilation error

[Brendan Higgins]

On Wed, Jul 20, 2022 at 2:57 PM Maíra Canal <mairacanal@riseup.net> wrote:
>
> The Parameterized Testing example contains a compilation error, as the
> signature for the description helper function is void(*)(const struct
> sha1_test_case *, char *), and the struct is non-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@riseup.net>

Thanks!

Reviewed-by: Brendan Higgins <brendanhiggins@google.com>