From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by sourceware.org (Postfix) with ESMTPS id 93C8C3857C6A for ; Thu, 10 Mar 2022 14:17:32 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 93C8C3857C6A Received: from mail-qt1-f200.google.com (mail-qt1-f200.google.com [209.85.160.200]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-515-z6K77Aq7MJWVqvqcmeKIKw-1; Thu, 10 Mar 2022 09:17:31 -0500 X-MC-Unique: z6K77Aq7MJWVqvqcmeKIKw-1 Received: by mail-qt1-f200.google.com with SMTP id r13-20020ac85c8d000000b002e0234f9bb5so4158725qta.0 for ; Thu, 10 Mar 2022 06:17:31 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:references:from:in-reply-to :content-transfer-encoding; bh=vfsTD7/WUs7x+fG901cqB6vEQXkptZNlgaMew4vsYJk=; b=MKxZAFGCzWaNARXx29N+nWAt1HhaEOM6R+CjOvh2oLNiw/b2jDlL7vxiBekbJvzWjP 4UxgVZjjNOAIIkIAFoUdz2vslxLIU+PHxWugTBNtv9bWj4kan23CyaGNCyKFa/0/RALM DfxX+2hN0xhmt+MWpjBKx80YRy1a4to0avNE5F2lk/3UjYYYJNWUcIWM87wmplhnZ+e5 EnhyVc25tM7SrhEGk5JClSDMTckWR7kNkphLsa7owGsJnGCllvO4Gsj0o1BpEmjhjLv6 Ur22QisimqkyRf4brMSmM1FbJa8L7Tiea7PgNaEIsVJ/OIjSlU1DRf1cSOqtnVg21B6H qTNQ== X-Gm-Message-State: AOAM531q2tDMaEEMDG3EfK/bwjJUDkdmgwC2S0WokcJwe8GIgPae8loe wj5eud6Tl4bVyT32DhCFUINwfha1F5e2RwBb9fule0QOygMpJVDv0/0vsOHeI+jzpIBv44DxFuN Ul5OZ9ppgt0x0oOHiQg== X-Received: by 2002:ac8:24d:0:b0:2d5:e1f1:d492 with SMTP id o13-20020ac8024d000000b002d5e1f1d492mr4119350qtg.348.1646921850727; Thu, 10 Mar 2022 06:17:30 -0800 (PST) X-Google-Smtp-Source: ABdhPJxNSIR53WhEQBy01UCFXB4Xmzl6xSnYdfWAQheeGFrG2Fnht4yS7+4BFjCB8F4R4QAsPAkLOg== X-Received: by 2002:ac8:24d:0:b0:2d5:e1f1:d492 with SMTP id o13-20020ac8024d000000b002d5e1f1d492mr4119321qtg.348.1646921850365; Thu, 10 Mar 2022 06:17:30 -0800 (PST) Received: from [192.168.1.149] (130-44-159-43.s15913.c3-0.arl-cbr1.sbo-arl.ma.cable.rcncustomer.com. [130.44.159.43]) by smtp.gmail.com with ESMTPSA id x12-20020a05620a12ac00b0067d4bfffc59sm1237041qki.118.2022.03.10.06.17.29 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 10 Mar 2022 06:17:29 -0800 (PST) Message-ID: <06a1aca7-5096-8214-152d-35b2800d5ed7@redhat.com> Date: Thu, 10 Mar 2022 09:17:29 -0500 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.6.1 Subject: Re: [PATCH] call mark_dfs_back_edges() before testing EDGE_DFS_BACK [PR104761] To: Martin Sebor , gcc-patches References: From: Jason Merrill In-Reply-To: X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-6.7 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, NICE_REPLY_A, RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H5, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_NONE, TXREP, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: gcc-patches@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 10 Mar 2022 14:17:33 -0000 On 3/2/22 19:15, Martin Sebor wrote: > The -Wdangling-pointer code tests the EDGE_DFS_BACK but the pass never > calls the mark_dfs_back_edges() function that initializes the bit (I > didn't know about it).  As a result the bit is not set when expected, > which can cause false positives under the right conditions. > > The attached patch adds a call to the warning pass to initialize > the bit.  Tested on x86_64-linux. OK on Monday if no other comments. Jason