From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750842AbaFIEL3 (ORCPT ); Mon, 9 Jun 2014 00:11:29 -0400 Received: from smtprelay0227.hostedemail.com ([216.40.44.227]:47520 "EHLO smtprelay.hostedemail.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750720AbaFIELZ (ORCPT ); Mon, 9 Jun 2014 00:11:25 -0400 X-Session-Marker: 6A6F6540706572636865732E636F6D X-Spam-Summary: 2,0,0,,d41d8cd98f00b204,joe@perches.com,:::::,RULES_HIT:41:355:379:541:800:960:973:982:988:989:1260:1261:1277:1311:1313:1314:1345:1373:1437:1515:1516:1518:1534:1541:1593:1594:1711:1730:1747:1777:1792:2197:2199:2393:2559:2562:2828:3138:3139:3140:3141:3142:3352:3653:3865:3866:3868:3870:3871:4321:4823:5007:7652:7903:7904:10004:10400:10848:11658:11914:12043:12296:12438:12517:12519:12555:13069:13311:13357,0,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 X-HE-Tag: gate05_c330c7e90a2c X-Filterd-Recvd-Size: 2132 Message-ID: <1402287082.9150.7.camel@joe-AO725> Subject: [PATCH] checkpatch: warn on unnecessary else after return or break From: Joe Perches To: Andrew Morton Cc: Andy Whitcroft , LKML Date: Sun, 08 Jun 2014 21:11:22 -0700 Content-Type: text/plain; charset="ISO-8859-1" X-Mailer: Evolution 3.10.4-0ubuntu1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Using an else following a break or return can unnecessarily indent code blocks. ie: for (i = 0; i < 100; i++) { int foo = bar(); if (foo < 1) break; else usleep(1); } is generally better written as: for (i = 0; i < 100; i++) { int foo = bar(); if (foo < 1) break; usleep(1); } Warn when a bare else statement is preceded by a break or return indented 1 tab more than the else. Signed-off-by: Joe Perches --- scripts/checkpatch.pl | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index 010b18e..9059fd0 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -2342,6 +2342,16 @@ sub process { # check we are in a valid C source file if not then ignore this hunk next if ($realfile !~ /\.(h|c)$/); +# check indentation of any line with a bare else +# if the previous line is a break or return and is indented 1 tab more... + if ($sline =~ /^\+([\t]+)(?:}[ \t]*)?else(?:[ \t]*{)?\s*$/) { + my $tabs = length($1) + 1; + if ($prevline =~ /^\+\t{$tabs,$tabs}(?:break|return)\b/) { + WARN("UNNECESSARY_ELSE", + "else is not generally useful after a break or return\n" . $hereprev); + } + } + # discourage the addition of CONFIG_EXPERIMENTAL in #if(def). if ($line =~ /^\+\s*\#\s*if.*\bCONFIG_EXPERIMENTAL\b/) { WARN("CONFIG_EXPERIMENTAL",