Return-path: Received: from smtprelay0225.hostedemail.com ([216.40.44.225]:45826 "EHLO smtprelay.hostedemail.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932766AbcHNMHI (ORCPT ); Sun, 14 Aug 2016 08:07:08 -0400 Message-ID: <1471176423.5201.7.camel@perches.com> (sfid-20160814_140728_287552_B24E0221) Subject: Re: [PATCH] Staging: rtl8723au: os_intfs: fixed case statement is variable issue From: Joe Perches To: sunbing , Jes Sorensen Cc: Larry.Finger@lwfinger.net, gregkh@linuxfoundation.org, linux-wireless@vger.kernel.org, devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org, sunbing.linux@gmail.com, Johannes Berg Date: Sun, 14 Aug 2016 05:07:03 -0700 In-Reply-To: References: <1470924695-14931-1-git-send-email-sunbing@redflag-linux.com> <7FC388BC-FD87-44C6-87D3-AC041F1393DB@redflag-linux.com> Content-Type: text/plain; charset="ISO-8859-1" Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Sat, 2016-08-13 at 17:26 +0800, sunbing wrote: > On Aug 12, 2016, at 22:30, Jes Sorensen wrote: > > sunbing writes: > > > On Aug 11, 2016, at 23:25, Jes Sorensen wrote: > > > > Bing Sun writes: > > > > > > > > > > Fixed sparse parse error: > > > > > Expected constant expression in case statement. [] > > > > Pardon me here, but I find it really hard to see how this change is an > > > > improvement over the old code in any shape or form. > > > There is no functional improvement.? > > > But before this patch, when we do: make C=1 M=drivers/staging/rtl8723au/ > > > An error output:? > > > drivers/staging/rtl8723au//os_dep/os_intfs.c:287:14: error: Expected > > > constant expression in case statement > > > To avoid sparse parse error, a case statement converts to an if statement. > > > So we got this patch. > > Hello > > > > I understand this part, but it seems to me we are changing the code due > > to a broken test case in sparse. Does the warning go away if you use > > __constant_htons() instead of htons()? > > > > Jes > Thanks for your guidance. > > 1. If I use __constant_htons, checkpatch.pl will warning: > ????WARNING: __constant_htons should be htons > > 2. In os_intfs.c: rtw_classify8021d, there are only one case statement and a? > default statement. So, convert "switch case" to "if else" is more readable in my opinion. > > So, I pushed this patch. > > There are some patches convert use of __constant_htons to htons in kernel logs.? > Will there be a new patch convert to htons in the future if I use??__constant_htons now ? > > After search through kernel code, there are 158 "case htons(...)" statements and? > 2 "case __constant_htons(...)" statements. Does this mean we can ignore sparse? > error and use "case htons(...)" ? > > It makes me confused. More help, please. It's a sparse defect. Try again after patching sparse with Jes' patch: http://marc.info/?l=linux-sparse&m=147091200720267&w=3