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X-OriginatorOrg: arm.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 23 Feb 2023 19:11:01.4473 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 1864b339-d3a8-48ca-dbe6-08db15d1b3fc X-MS-Exchange-CrossTenant-Id: f34e5979-57d9-4aaa-ad4d-b122a662184d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=f34e5979-57d9-4aaa-ad4d-b122a662184d;Ip=[63.35.35.123];Helo=[64aa7808-outbound-1.mta.getcheckrecipient.com] X-MS-Exchange-CrossTenant-AuthSource: AM7EUR03FT026.eop-EUR03.prod.protection.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: AS8PR08MB9096 X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,FORGED_SPF_HELO,KAM_DMARC_NONE,RCVD_IN_DNSWL_NONE,RCVD_IN_MSPIKE_H2,RCVD_IN_VALIDITY_RPBL,SPF_HELO_PASS,SPF_NONE,TXREP,UNPARSEABLE_RELAY autolearn=no autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: Hi Adhemerval,=0A= =0A= What kind of readahead are you trying to test/fix here? It's not clear from= the=0A= patch... So with strcmp you can safely call strlen on either input, and sim= ilarly I=0A= believe you can call strnlen on both inputs of strncmp without getting a cr= ash.=0A= That means it is possible to read ahead as long as you never read past a ze= ro=0A= byte or past the given size.=0A= =0A= If you couldn't read even a single byte past the first mismatch it would be= hard=0A= to create efficient implementations, especially with wide vectors...=0A= =0A= Cheers,=0A= Wilco=