From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Subject: Re: [PATCH] rds: send: mark expected switch fall-through in rds_rm_size To: Santosh Shilimkar , "Gustavo A. R. Silva" Cc: "David S. Miller" , netdev@vger.kernel.org, linux-rdma@vger.kernel.org, rds-devel@oss.oracle.com, linux-kernel@vger.kernel.org References: <20180219181020.GA19154@embeddedgus> <9b385269-7f13-983c-caf1-72e050acc6d9@oracle.com> From: "Gustavo A. R. Silva" Message-ID: <56eff85f-852b-0123-ae57-7cf9baedbae6@embeddedor.com> Date: Tue, 20 Feb 2018 12:05:26 -0600 MIME-Version: 1.0 In-Reply-To: <9b385269-7f13-983c-caf1-72e050acc6d9@oracle.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: Hi Santosh, On 02/20/2018 11:54 AM, Santosh Shilimkar wrote: > Hi, > > 2/19/2018 10:10 AM, Gustavo A. R. Silva wrote: >> In preparation to enabling -Wimplicit-fallthrough, mark switch cases >> where we are expecting to fall through. >> >> Addresses-Coverity-ID: 1465362 ("Missing break in switch") >> Signed-off-by: Gustavo A. R. Silva >> --- >>   net/rds/send.c | 2 ++ >>   1 file changed, 2 insertions(+) >> >> diff --git a/net/rds/send.c b/net/rds/send.c >> index 028ab59..79d158b 100644 >> --- a/net/rds/send.c >> +++ b/net/rds/send.c >> @@ -902,6 +902,8 @@ static int rds_rm_size(struct msghdr *msg, int >> num_sgs) >>           case RDS_CMSG_ZCOPY_COOKIE: >>               zcopy_cookie = true; >> +            /* fall through */ >> + >>           case RDS_CMSG_RDMA_DEST: >>           case RDS_CMSG_RDMA_MAP: >>               cmsg_groups |= 2; >> > So coverity greps for commet as "fall through" for > -Wimplicit-fallthrough build ? > No. Basically, Coverity only reports cases in which a break, return or continue statement is missing. Now, if the statements I mention above are missing and if you add the following line to your Makefile: KBUILD_CFLAGS += $(call cc-option,-Wimplicit-fallthrough) You will get a warning if a fall-through comment is missing. > Adding that comments itself if fine but was curious > about it if some one makes a spell error in this > comment what happens ;-) > In this case, Coverity would still report the same "Missing break in switch" error, but you'll get a GCC warning. > For patch itself, > Acked-by: Santosh Shilimkar -- Gustavo