From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754835AbcITSDu (ORCPT ); Tue, 20 Sep 2016 14:03:50 -0400 Received: from smtprelay0059.hostedemail.com ([216.40.44.59]:58466 "EHLO smtprelay.hostedemail.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755674AbcITSDr (ORCPT ); Tue, 20 Sep 2016 14:03:47 -0400 X-Session-Marker: 6A6F6540706572636865732E636F6D X-Spam-Summary: 2,0,0,,d41d8cd98f00b204,joe@perches.com,:::::::::,RULES_HIT:41:355:379:541:599:973:988:989:1260:1277:1311:1313:1314:1345:1359:1373:1437:1515:1516:1518:1534:1541:1593:1594:1711:1730:1747:1777:1792:2194:2199:2393:2553:2559:2562:2828:3138:3139:3140:3141:3142:3353:3622:3865:3866:3867:3868:3870:3871:3872:4321:5007:9008:10004:10400:10848:11026:11232:11473:11657:11658:11914:12043:12295:12296:12740:13069:13311:13357:13439:13894:14659:14721:21080:21324:21451:30012:30034:30054:30090:30091,0,RBL:none,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fn,MSBL:0,DNSBL:none,Custom_rules:0:0:0,LFtime:3,LUA_SUMMARY:none X-HE-Tag: wood39_5b03dfffe3061 X-Filterd-Recvd-Size: 2826 Message-ID: <1474394624.1954.45.camel@perches.com> Subject: Re: Possible code defects: macros and precedence From: Joe Perches To: Julia Lawall Cc: Dan Carpenter , LKML , Andrew Morton , netdev Date: Tue, 20 Sep 2016 11:03:44 -0700 In-Reply-To: <1474391253.1954.39.camel@perches.com> References: <1472927739.5018.13.camel@perches.com> <1473001581.5018.37.camel@perches.com> <1474147658.1954.1.camel@perches.com> <1474191110.1954.16.camel@perches.com> <1474391253.1954.39.camel@perches.com> Content-Type: text/plain; charset="ISO-8859-1" X-Mailer: Evolution 3.21.91-1ubuntu1 Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2016-09-20 at 10:07 -0700, Joe Perches wrote: > On Tue, 2016-09-20 at 15:14 +0200, Julia Lawall wrote: > > The semantic patch below finds a binary operator in a macro and a binary > > operator in the use of the macro, and checks if the priority of the > > operator in the macro is higher (lower number) than the priority of the > > operator in the use.  If this is the case, it adds parentheses in the use, > > which is not what one wants, but serves to show where the problem is > Thanks, this works on the trivial example I suggested > without an #include > > I've tried it on trivial files with --recursive-includes > and it seems to work there too. I tried it on drivers/net with --recursive-includes and got just 1 hit on an old and probably relatively untested driver. No hardware, can't test. It may be correct now. Who knows... --- diff --urN a/drivers/net/ethernet/smsc/smc911x.h b/drivers/net/ethernet/smsc/smc911x.h --- a/drivers/net/ethernet/smsc/smc911x.h +++ b/drivers/net/ethernet/smsc/smc911x.h @@ -700,8 +700,8 @@ static const struct chip_id chip_ids[] = * capabilities. Please use those and not the in/out primitives. */ /* FIFO read/write macros */ -#define SMC_PUSH_DATA(lp, p, l) SMC_outsl( lp, TX_DATA_FIFO, p, (l) >> 2 ) -#define SMC_PULL_DATA(lp, p, l) SMC_insl ( lp, RX_DATA_FIFO, p, (l) >> 2 ) +#define SMC_PUSH_DATA(lp, p, l) SMC_outsl( lp, TX_DATA_FIFO, p, ((l) >> 2) ) +#define SMC_PULL_DATA(lp, p, l) SMC_insl ( lp, RX_DATA_FIFO, p, ((l) >> 2) ) #define SMC_SET_TX_FIFO(lp, x) SMC_outl( x, lp, TX_DATA_FIFO ) #define SMC_GET_RX_FIFO(lp) SMC_inl( lp, RX_DATA_FIFO )