Re: [PATCH v2 1/2] IB/qib: remove superfluous fallthrough statements

From: Alex Dewar
Date: Thu Aug 27 2020 - 06:40:40 EST


On Wed, Aug 26, 2020 at 08:41:20PM -0500, Gustavo A. R. Silva wrote:
> On Wed, Aug 26, 2020 at 09:11:49PM -0300, Jason Gunthorpe wrote:
> > On Wed, Aug 26, 2020 at 02:18:59PM -0500, Gustavo A. R. Silva wrote:
> > > Hi,
> > >
> > > On Tue, Aug 25, 2020 at 02:33:27PM -0500, Gustavo A. R. Silva wrote:
> > > > On Tue, Aug 25, 2020 at 06:12:42PM +0100, Alex Dewar wrote:
> > > > > Commit 36a8f01cd24b ("IB/qib: Add congestion control agent implementation")
> > > > > erroneously marked a couple of switch cases as /* FALLTHROUGH */, which
> > > > > were later converted to fallthrough statements by commit df561f6688fe
> > > > > ("treewide: Use fallthrough pseudo-keyword"). This triggered a Coverity
> > > > > warning about unreachable code.
> > > > >
> > > >
> > > > It's worth mentioning that this warning is triggered only by compilers
> > > > that don't support __attribute__((__fallthrough__)), which has been
> > > > supported since GCC 7.1.
> > > >
> > > > > Remove the fallthrough statements.
> > > > >
> > > > > Addresses-Coverity: ("Unreachable code")
> > > > > Fixes: 36a8f01cd24b ("IB/qib: Add congestion control agent implementation")
> > > > > Signed-off-by: Alex Dewar <alex.dewar90@xxxxxxxxx>
> > > >
> > > > Reviewed-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>
> > > >
> > >
> > > I can take this in my tree for 5.9-rc3.
> >
> > That would make conflicts for the 2nd patch, lets just send them all
> > through the rdma tree please.
>
> OK.
>
> > Is there a reason this is -rc material?
>
> It's just that this warning is currently in mainline.

FYI this issue was found with Coverity, not a compiler. I just built the
unfixed version from mainline (with gcc 10.2.0) and didn't get any
warnings.

>
> Thanks
> --
> Gustavo