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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id AB5D9C433FE for ; Sat, 26 Feb 2022 22:14:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229851AbiBZWPK (ORCPT ); Sat, 26 Feb 2022 17:15:10 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48536 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229802AbiBZWPJ (ORCPT ); Sat, 26 Feb 2022 17:15:09 -0500 Received: from mout.kundenserver.de (mout.kundenserver.de [212.227.17.10]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8CA961DF847; Sat, 26 Feb 2022 14:14:33 -0800 (PST) Received: from mail-wm1-f53.google.com ([209.85.128.53]) by mrelayeu.kundenserver.de (mreue107 [213.165.67.113]) with ESMTPSA (Nemesis) id 1M8xwu-1nKFJh3DWw-0066R7; Sat, 26 Feb 2022 23:14:31 +0100 Received: by mail-wm1-f53.google.com with SMTP id c192so3637559wma.4; Sat, 26 Feb 2022 14:14:31 -0800 (PST) X-Gm-Message-State: AOAM531ND0p4kXnNDC2sgqSdiW71n870mm+gJysDzjYw/NmMtaNszQjt wlJU2aBNAFW+iL2bAA+RjPmAOtUvbUffsQIyE9M= X-Google-Smtp-Source: ABdhPJzDQiG2WJNNyU8zXyeqkp2/I2pIvAnATyav1sudQ7qVyIelNKbafaciVu8AmGz8pwOL7x9RptXoWVX/tSfEtXg= X-Received: by 2002:a05:600c:1d27:b0:37c:74bb:2b4d with SMTP id l39-20020a05600c1d2700b0037c74bb2b4dmr8048471wms.82.1645913671403; Sat, 26 Feb 2022 14:14:31 -0800 (PST) MIME-Version: 1.0 References: <20220217184829.1991035-1-jakobkoschel@gmail.com> <20220217184829.1991035-4-jakobkoschel@gmail.com> <6DFD3D91-B82C-469C-8771-860C09BD8623@gmail.com> <20220226124249.GU614@gate.crashing.org> In-Reply-To: <20220226124249.GU614@gate.crashing.org> From: Arnd Bergmann Date: Sat, 26 Feb 2022 23:14:15 +0100 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [RFC PATCH 03/13] usb: remove the usage of the list iterator after the loop To: Segher Boessenkool Cc: Linus Torvalds , Jakob , Arnd Bergmann , Linux Kernel Mailing List , linux-arch , Greg Kroah-Hartman , Thomas Gleixner , Andy Shevchenko , Andrew Morton , Kees Cook , Mike Rapoport , "Gustavo A. R. Silva" , Brian Johannesmeyer , Cristiano Giuffrida , "Bos, H.J." Content-Type: text/plain; charset="UTF-8" X-Provags-ID: V03:K1:xn4Py0/5Y7Hjx1O//gsXYXBSKmsbC6odn+cPwMNzUI8Y+fIeSSP Hj462lJ4Q4D5EFIrLOOh2pwGhu7tuZ7S/1BVZvLoG6DAYkIeZgdVGPQCKK2Gm3Cekf/1PgR /C3ouG85TCr9oBOySbCjNHXt9t83BU3qhV2iPur8UX/CuFj7DotbZVQUZX5zbMqTdYRlBow CY4yER406apypIAcPVDJg== X-UI-Out-Filterresults: notjunk:1;V03:K0:qjD9mkA5UcY=:StnJtyKtnG8xOJDRhVQhLw 12qJNthjXWjR24fOAGFkBoxgNE+jlqosTdOOJEzTuLj3o0hAZ10iFcm5behvSkaY0uRLhP6zf A3p2fPIaRiYux6VAeSpOnGO48dda32K8fMh9hxeGT+hrEkX343cbCZkWB7eBm1mM6fNBmN5C0 +ywKLCj0MAH1FvT567NaXZZU3fnbgmKytopgnu/eEYPaMsagy1cRcYU1ucNg3vGGC7DuGsL1e bIZCLnXZkfsP0MQJ2QhXSJO8pp1QwTaUXM7QwYDEMSv9VQAgL13g1wrqr9Lv6AwYrg20+1Yhl VGoySiWGL5k3cPvLQaos1uh/xugE87Tv0Vj66Qs9Sloi/1IWKBsUNq6zZsAzUcKuachba6+NV p/KUkQXh+sY/upvg7sRzO+QVJKNtlwOkAArrpG8Yaw0C1Bw6JwSL16GB0/EzcCS7S77yzSCCa Pbpb26Fo9sN9jt45eHjVYvDWz9Hlr3jfX6iMmw8jVCU7o/l/U0V+Zvg++iN2+uLL5sr347XVE /wzKE5mLj02cyWn5u0Pgo/9j4hq4TpLDhuhyNjNBesnTZx2y1IUdjf9JdsJPVItexVEGtgHn9 0SrQDgelixKlggD7x2OkqW35B6nNSbbICfz92XAFSQywE0K2t5jGfkc6lstfxGYPW8F4cXtuc AIoA0aitl9tL9EfzbI+idu3PXaVS/R08CK5E3F6BPYPttbU98aiD/t4N2yH//vY561Vp0L8Ct 0AXBufQRlXvaBlhGpWrro40mXDUlz4mqIMOFHURP6edgsOSoOAZvBBRBBgRuLBVk1djSJWB/i 5iUokMkxa4Ns/fNegjc6f16I5m9JFDaE3x9McEcANFuAqIJf74= Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Feb 26, 2022 at 1:42 PM Segher Boessenkool wrote: > On Wed, Feb 23, 2022 at 11:23:39AM -0800, Linus Torvalds wrote: > > That said, we seem to only have two cases of it in the kernel, at > > least by a x86-64 allmodconfig build. So we could examine the types > > there, or we could just add '-Wno-shift-negative-value". > > Yes. > > The only reason the warning exists is because it is undefined behaviour > (not implementation-defined or anything). The reason it is that in the > standard is that it is hard to implement and even describe for machines > that are not two's complement. However relevant that is today :-) Could gcc follow the clang behavior then and skip the warning and sanitizer for this case when -fno-strict-overflow or -fwrapv are used? Arnd