On Tue, 2020-09-15 at 19:01 -0500, Gustavo A. R. Silva wrote:
>
> On 9/15/20 18:51, Gustavo A. R. Silva wrote:
> >
> > On 9/15/20 18:29, Joe Perches wrote:
> > > On Tue, 2020-09-15 at 15:57 -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 removed the comment.
> > > []
> > > > diff --git a/fs/nfs/super.c b/fs/nfs/super.c
> > > []
> > > > @@ -889,7 +889,6 @@ static struct nfs_server *nfs_try_mount_request(struct fs_context *fc)
> > > > default:
> > > > if (rpcauth_get_gssinfo(flavor, &info) != 0)
> > > > continue;
> > > > - fallthrough;
> > >
> > > My preference would be to convert the fallthrough
> > > to a break here so if someone ever adds another
> > > label after default: for any reason, the code would
> > > still work as expected.
> >
> > I agree with Joe.
>
> Actually, this is part of the work I plan to do to enable -Wimplicit-fallthrough
> for Clang: audit every place where we could use a break instead of a fallthrough.
>
> I'm on vacation this week. So, I'll get back to this next week.
Nice, thanks Gustavo.
As part of that work, perhaps you could also find all the
switch (<foo>) {
[cases...]
[code...];
break;
default:
[code...]
(no break)
}
uawa where the last label/default block does _not_ have a break
statement and add one too.
Also see: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91432
gcc does _not_ warn on
switch (<foo>) {
case BAR:
[code];
(no fallthrough)
case BAZ:
break;
}
It might be good to add the appropriate fallthrough
for those case blocks too.
