Re: [PATCH] staging: atomisp: Fix fallthrough keyword warning

From: Dan Carpenter
Date: Mon Aug 31 2020 - 09:40:46 EST


On Mon, Aug 31, 2020 at 04:30:12PM +0300, Cengiz Can wrote:
> commit df561f6688fe ("treewide: Use fallthrough pseudo-keyword") from
> Gustavo A. R. Silva replaced and standardized /* fallthrough */ comments
> with 'fallthrough' pseudo-keyword.
>
> However, in one of the switch-case statements, Coverity Static Analyzer
> throws a warning that 'fallthrough' is unreachable due to the adjacent
> 'return false' statement.
>
> Since 'fallthrough' is actually an empty "do {} while(0)" this might be
> due to compiler optimizations. But that needs further investigation.
>
> In order to fix the unreachable code warning, make adjacent 'return
> false' a part of the previous if statement's else clause.
>
> Reported-by: Coverity Static Analyzer CID 1466511
> Signed-off-by: Cengiz Can <cengiz@xxxxxxxxxx>
> ---
> drivers/staging/media/atomisp/pci/atomisp_compat_css20.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/staging/media/atomisp/pci/atomisp_compat_css20.c b/drivers/staging/media/atomisp/pci/atomisp_compat_css20.c
> index 1b2b2c68025b..aaa2d0e0851b 100644
> --- a/drivers/staging/media/atomisp/pci/atomisp_compat_css20.c
> +++ b/drivers/staging/media/atomisp/pci/atomisp_compat_css20.c
> @@ -709,8 +709,8 @@ static bool is_pipe_valid_to_current_run_mode(struct atomisp_sub_device *asd,
> if (pipe_id == IA_CSS_PIPE_ID_CAPTURE ||
> pipe_id == IA_CSS_PIPE_ID_PREVIEW)
> return true;
> -
> - return false;
> + else
> + return false;
> fallthrough;

Heh... Still unreachable, but now it has a checkpatch.pl warning as
well. Just get rid of the bogus fallthrough annotation.

> case ATOMISP_RUN_MODE_VIDEO:
> if (!asd->continuous_mode->val) {

regards,
dan carpenter