Re: [PATCH v2] nfs: remove incorrect fallthrough label

From: Joe Perches
Date: Wed Sep 16 2020 - 16:19:48 EST

On Wed, 2020-09-16 at 13:02 -0700, Nick Desaulniers wrote:
> There is no case after the default from which to fallthrough to. Clang
> will error in this case (unhelpfully without context, see link below)
> and GCC will with -Wswitch-unreachable.
> The previous commit should have just replaced the comment with a break
> statement.

> If we consider implicit fallthrough to be a design mistake of C, then
> all case statements should be terminated with one of the following
> statements:
> * break
> * continue
> * return
> * __attribute__(__fallthrough__)

Just fallthrough. __attribute__((__fallthrough__)
is only used once in code for the #define.

And maybe add see: Documentation/process/deprecated.rst

> * goto (plz no)

goto is a valid style inside a switch/case label block.

There are more than 1500 of these goto <label> uses in the
kernel so the 'please no' here doesn't seem reasonable.

> * (call of function with __attribute__(__noreturn__))

I guess panic counts. I count 11 of those.

Are there any other uses of functions with __noreturn
in switch/case label blocks?