From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DD182C2BB84 for ; Fri, 4 Sep 2020 23:35:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AC35B20C09 for ; Fri, 4 Sep 2020 23:35:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1599262553; bh=6WT/eIjHIIiMrlzdI/sZtAds5GrfVF+meLSclJlcCyk=; h=Date:From:To:Subject:In-Reply-To:Reply-To:List-ID:From; b=JMcb9VWQoYXuInhroYj2pvpqpqrIOP39TAcE9IaQ7k7iVoiesKbJOBa2WLjrUaFlo a+ZIn9h96FIaA0VzhrRNuVYOPb3Rxrhq+v1sftdj3b5GjDbDuOQNtVBrS2HqrFwjCO /o1dxXqseDFg+G9AxNRu/6Rksrxhqtv6ryNjUHsE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728186AbgIDXfx (ORCPT ); Fri, 4 Sep 2020 19:35:53 -0400 Received: from mail.kernel.org ([198.145.29.99]:38868 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726456AbgIDXfx (ORCPT ); Fri, 4 Sep 2020 19:35:53 -0400 Received: from localhost.localdomain (c-71-198-47-131.hsd1.ca.comcast.net [71.198.47.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 58E80208C7; Fri, 4 Sep 2020 23:35:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1599262552; bh=6WT/eIjHIIiMrlzdI/sZtAds5GrfVF+meLSclJlcCyk=; h=Date:From:To:Subject:In-Reply-To:From; b=NXdkWHIV/r+nGvtWJ5kG09Tp7QrwfBezrOztZLvGe+8apdj68uXoi4xZbCXvdgEZA FQARw7MuyZUFDqnSva3ym8cfOHVyRMC0Qi7UWrg5eNsg3nFCdbZKOZK5GsloHwgmO0 oyQv8aLVJXsXb7CpOCtE/c7GCntFOSafVjqzXgmQ= Date: Fri, 04 Sep 2020 16:35:52 -0700 From: Andrew Morton To: akpm@linux-foundation.org, joe@perches.com, linux-mm@kvack.org, lukas.bulwahn@gmail.com, mm-commits@vger.kernel.org, mrinalmni@gmail.com, torvalds@linux-foundation.org Subject: [patch 10/19] checkpatch: fix the usage of capture group ( ... ) Message-ID: <20200904233552.kLq6B7QPc%akpm@linux-foundation.org> In-Reply-To: <20200904163454.4db0e6ce0c4584d2653678a3@linux-foundation.org> User-Agent: s-nail v14.8.16 Sender: mm-commits-owner@vger.kernel.org Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: Mrinal Pandey Subject: checkpatch: fix the usage of capture group ( ... ) The usage of "capture group (...)" in the immediate condition after `&&` results in `$1` being uninitialized. This issues a warning "Use of uninitialized value $1 in regexp compilation at ./scripts/checkpatch.pl line 2638". I noticed this bug while running checkpatch on the set of commits from v5.7 to v5.8-rc1 of the kernel on the commits with a diff content in their commit message. This bug was introduced in the script by commit e518e9a59ec3 ("checkpatch: emit an error when there's a diff in a changelog"). It has been in the script since then. The author intended to store the match made by capture group in variable `$1`. This should have contained the name of the file as `[\w/]+` matched. However, this couldn't be accomplished due to usage of capture group and `$1` in the same regular expression. Fix this by placing the capture group in the condition before `&&`. Thus, `$1` can be initialized to the text that capture group matches thereby setting it to the desired and required value. Link: https://lkml.kernel.org/r/20200714032352.f476hanaj2dlmiot@mrinalpandey Fixes: e518e9a59ec3 ("checkpatch: emit an error when there's a diff in a changelog") Signed-off-by: Mrinal Pandey Reviewed-by: Lukas Bulwahn Tested-by: Lukas Bulwahn Cc: Joe Perches Signed-off-by: Andrew Morton --- scripts/checkpatch.pl | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/scripts/checkpatch.pl~checkpatch-fix-the-usage-of-capture-group +++ a/scripts/checkpatch.pl @@ -2639,8 +2639,8 @@ sub process { # Check if the commit log has what seems like a diff which can confuse patch if ($in_commit_log && !$commit_log_has_diff && - (($line =~ m@^\s+diff\b.*a/[\w/]+@ && - $line =~ m@^\s+diff\b.*a/([\w/]+)\s+b/$1\b@) || + (($line =~ m@^\s+diff\b.*a/([\w/]+)@ && + $line =~ m@^\s+diff\b.*a/[\w/]+\s+b/$1\b@) || $line =~ m@^\s*(?:\-\-\-\s+a/|\+\+\+\s+b/)@ || $line =~ m/^\s*\@\@ \-\d+,\d+ \+\d+,\d+ \@\@/)) { ERROR("DIFF_IN_COMMIT_MSG", _