Re: [PATCH 032/141] floppy: Fix fall-through warnings for Clang

From: Jens Axboe
Date: Tue Apr 20 2021 - 16:30:37 EST


On 4/20/21 2:25 PM, Gustavo A. R. Silva wrote:
> Hi all,
>
> Friendly ping: who can take this, please?
>
> Thanks
> --
> Gustavo
>
> On 11/20/20 12:28, Gustavo A. R. Silva wrote:
>> In preparation to enable -Wimplicit-fallthrough for Clang, fix a warning
>> by explicitly adding a fallthrough pseudo-keyword in places where the
>> code is intended to fall through to the next case.
>>
>> Link: https://github.com/KSPP/linux/issues/115
>> Signed-off-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>
>> ---
>> drivers/block/floppy.c | 1 +
>> 1 file changed, 1 insertion(+)
>>
>> diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c
>> index 7df79ae6b0a1..21a2a7becba0 100644
>> --- a/drivers/block/floppy.c
>> +++ b/drivers/block/floppy.c
>> @@ -2124,6 +2124,7 @@ static void format_interrupt(void)
>> switch (interpret_errors()) {
>> case 1:
>> cont->error();
>> + fallthrough;
>> case 2:
>> break;
>> case 0:

I wonder about the consistency of the patches. The one I just applied
for libata adds a break, this one annotates fallthrough. But the cases
are really 100% the same. Why aren't the changes consistent? Both are
obviously fine, but for identical cases it seems odd that they differ.

IMHO, adding a break makes more sense. Annotate the fallthrough if the
two cases share work that needs to be done, as then that solution makes
sense.

--
Jens Axboe