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Sun, 14 Jul 2019 19:44:52 +0200 (CEST) Received: from [134.155.36.73] (edv13.bib.uni-mannheim.de [134.155.36.73]) by smtp.mail.uni-mannheim.de (Postfix) with ESMTPSA id 02715103D61; Sun, 14 Jul 2019 19:44:52 +0200 (CEST) To: Peter Maydell References: <030a439f-bb17-8232-bd1c-3585905e8feb@weilnetz.de> From: Stefan Weil Openpgp: preference=signencrypt Autocrypt: addr=sw@weilnetz.de; prefer-encrypt=mutual; keydata= mQINBFXCNBcBEACUbHx9FWsS1ATrhLGAS+Nc6bFQHPR3CpUQ4v++RiMg25bF6Ov1RsYEcovI 0DXGh6Ma+l6dRlvUXV8tMvNwqghDUr5KY7LN6tgcFKjBbXdv9VlKiWiMLKBrARcFKxx1sfLp 1P8RiaUdKsgy2Hq4T1PPy9ENTL1/FBG6P/Rw0rO9zOB+yNHcRJ5diDnERbi3x7qoaPUra2Ig lmQk/uxXKC0aNIhpNLNiQ+YpwTUN9q3eG6B9/3CG8RGtFzH9vDPlLvtUX+01a2gCifTi3iH3 8EEK8ACXIRs2dszlxMneKTvflXfvyCM1O+59wGcICQxltxLLhHSCJjOQyWdR2JUtn//XjVWM mf6bBT7Imx3DhhfFRlA+/Lw9Zah66DJrZgiV0LqoN/2f031TzD3FCBiGQEMC072MvSQ1DdJN OiRE1iWO0teLOxaFSbvJS9ij8CFSQQTnSVZs0YXGBal+1kMeaKo9sO4tkaAR2190IlMNanig CTJfeFqxzZkoki378grSHdGUTGKfwNPflTOA6Pw6xuUcxW55LB3lBsPqb0289P8o9dTR7582 e6XTkpzqe/z/fYmfI9YXIjGY8WBMRbsuQA30JLq1/n/zwxAOr2P9y4nqTMMgFOtQS8w4G46K UMY/5IspZp2VnPwvazUo2zpYiUSLo1hFHx2jrePYNu2KLROXpwARAQABtBxTdGVmYW4gV2Vp bCA8c3dAd2VpbG5ldHouZGU+iQI6BBMBCAAkAhsDBQsJCAcDBRUKCQgLBRYCAwEAAh4BAheA BQJV04LlAhkBAAoJEOCMIdVndFCtP5QP/1U8yWZzHeHufRFxtMsK1PERiLuKyGRH2oE5NWVc 5QQHZZ2ypXu53o2ZbZxmdy8+4lXiPWWwYVqto3V7bPaMTvQhIT0I3c3ZEZsvwyEEE6QdRs52 haZwX+TzNMQ5mOePdM2m4WqO0oU7YHU2WFf54MBmAGtj3FAQEAlZAaMiJs2aApw/4t35ICL1 Sb0FY8d8lKBbIFOAaFfrlQTC3y8eMTk1QxOVtdXpRrOl6OE0alWn97NRqeZlBm0P+BEvdgTP Qt+9rxbe4ulgKME2LkbDhLqf0m2+xMXb7T4LiHbQYnnWKGZyogpFaw3PuRVd9m8uxx1F8b4U jNzI9x2Ez5LDv8NHpSY0LGwvVmkgELYbcbyiftbuw81gJuM7k4IW5GR85kTH6y/Sq6JNaI4p 909IK8X4eeoCkAqEVmDOo1D5DytgxIV/PErrin82OIDXLENzOWfPPtUTO+H7qUe80NS2HLPG IveYSjuYKBB6n2JhPkUD7xxMEdh5Ukqi1WIBSV4Tuk3/ubHajP5bqg4QP3Wo1AyICX09A1QQ DajtMkyxXhYxr826EGcRD2WUUprGNYwaks4YiPuvOAJxSYprKWT6UDHzE3S8u4uZZm9H8cyg Fa3pysJwTmbmrBAP1lMolwXHky60dPnKPmFyArGC0utAH7QELXzBybnE/vSNttNT1D+HuQIN BFXcnj0BEAC32cCu2MWeqZEcvShjkoKsXk42mHrGbeuh/viVn8JOQbTO706GZtazoww2weAz uVEYhwqi7u9RATz9MReHf7R5F0KIRhc/2NhNNeixT/7L+E5jffH1LD+0IQdeLPoz6unvg7U/ 7OpdKWbHzPM3Lfd0N1dRP5sXULpjtYQKEgiOU58sc4F5rM10KoPFEMz8Ip4j9RbH/CbTPUM0 S4PxytRciB3Fjd0ECbVsErTjX7cZc/yBgs3ip7BPVWgbflhrc+utML/MwC6ZqCOIXf/U0ICY fp5I7PDbUSWgMFHvorWegMYJ9EzZ2nTvytL8E75C2U3j5RZAuQH5ysfGpdaTS76CRrYDtkEc ViTL+hRUgrX9qvqzCdNEePbQZr6u6TNx3FBEnaTAZ5GuosfUk7ynvam2+zAzLNU+GTywTZL2 WU+tvOePp9z1/mbLnH2LkWHgy3bPu77AFJ1yTbBXl5OEQ/PtTOJeC1urvgeNru26hDFSFyk4 gFcqXxswu2PGU7tWYffXZXN+IFipCS718eDcT8eL66ifZ8lqJ8Vu5WJmp9mr1spP9RYbT7Rw pzZ3iiz7e7AZyOtpSMIVJeYZTbtiqJbyN4zukhrTdCgCFYgf0CkA5UGpYXp2sXPr+gVxKX2p tj/gid4n95vR7KMeWV6DJ0YS4hKGtdhkuJCpJfjKP/e8TwARAQABiQIfBBgBCAAJBQJV3J49 AhsMAAoJEOCMIdVndFCtYRoQAJOu3RZTEvUBPoFqsnd849VmOKKg77cs+HD3xyLtp95JwQrz hwa/4ouDFrC86jt1vARfpVx5C8nQtNnWhg+5h5kyOIbtB1/27CCTdXAd/hL2k3GyrJXEc+i0 31E9bCqgf2KGY7+aXu4LeAfRIWJT9FGVzdz1f+77pJuRIRRmtSs8VAond2l+OcDdEI9Mjd9M qvyPJwDkDkDvsNptrcv4xeNzvX+2foxkJmYru6dJ+leritsasiAxacUowGB5E41RZEUg6bmV F4SMseIAEKWLy3hPGvYBOzADhq2YLgnM/wn9Y9Z7bEMy+w5e75saBbkFI7TncxDPUnIl/UTE KU1ORi5WWbvXYkUTtfNzZyD0/v3oojcIoZvK1OlpOtXHdlqOodjXF9nLe8eiVHyl8ZnzFxhe EW2QPvX8FLKqmSs9W9saQtk6bhv9LNYIYINjH3EEH/+bbmV+ln4O7a73Wm8L3tnpC3LmdGn2 Rm8B6J2ZK6ci1TRDiMpCUWefpnIuE+TibC5VJR5zx0Yh11rxxBFob8mWktRmLZyeEoCcZoBo sbJxD80QxWO03zPpkcJ7d4BrVsQ/BJkBtEe4Jn4iqHqA/OcrzwuEZSv+/MdgoqfblBZhDusm LYfVy7wFDeVClG6eQIiK2EnmDChLRkVIQzbkV0iG+NJVVJHLGK7/OsO47+zq Message-ID: <63d96e86-3823-2586-eb25-44beff91f8f2@weilnetz.de> Date: Sun, 14 Jul 2019 19:44:55 +0200 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Content-Language: en-GB X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 134.155.96.80 Subject: Re: [Qemu-devel] [BUG] 216 Alerts reported by LGTM for QEMU (some might be release critical) X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , Eduardo Habkost , QEMU Developers , Max Reitz , Paolo Bonzini , Richard Henderson Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Am 14.07.2019 um 19:30 schrieb Peter Maydell: [...] > "Analyzer thinks this multiply can overflow > but in fact it's not possible" is quite a common false > positive cause... The analysers don't complain because a multiply can overflow. They complain because the code indicates that a larger result is expected, for example uint64_t = uint32_t * uint32_t. They would not complain for the same multiplication if it were assigned to a uint32_t. So there is a simple solution to write the code in a way which avoids false positives... Stefan