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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 7D9CFC43387 for ; Tue, 8 Jan 2019 14:09:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 53F71206C0 for ; Tue, 8 Jan 2019 14:09:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729306AbfAHOJ6 convert rfc822-to-8bit (ORCPT ); Tue, 8 Jan 2019 09:09:58 -0500 Received: from mail-vk1-f195.google.com ([209.85.221.195]:36748 "EHLO mail-vk1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728839AbfAHOJ4 (ORCPT ); Tue, 8 Jan 2019 09:09:56 -0500 Received: by mail-vk1-f195.google.com with SMTP id 185so891969vkc.3; Tue, 08 Jan 2019 06:09:56 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=lBYfDnPVXDNQRdMrfaAMpkN7j7FL3/qAK52ZkVu2fys=; b=tVmm6bJf8DBwx9JY3qav7scbPj9+lzcv6vcSnYrG9wmsX+alw0aoLlwsr33F8EU8Cl W8SXwBKeXe9HnHR3qPU5L1qyKyoY/zLqpgIIEKiSgjBMMIgsNUo/VajRBFNVOW7eay4e LBERWxvWrK66tvh2LQ7p7b/f5hI7dm4GBwlzr8AuGzF2YSr3PRo593aNcCZs+4M9OcM0 iy4ThBw3N+Md0W1TVPu4hc+F2zdP7cqc9vxts0AQ7LuoAra6opiO5Vj+6IdbQbvOJGYx ki/vJp/WkeZ952ov4TSMqPhvYZ6VzOmkrHXArm5LXZjF+PjlcMBY8czNaC/k3dh9rRcp mgPw== X-Gm-Message-State: AJcUukcOsDl15n3pw/3oXPKtu1SuOH9fejiuDqp6ELP4C1ieC4UudHE3 C+tjiRePb+B6fqmrbRMD1gi4JN8pZ8v6SiS0+Zo= X-Google-Smtp-Source: ALg8bN6qFRYPO2P1ipa2zYPbcOuFnt82aRPxIbNYPlHO+iRlp4rKCHN4pCHhWU67m2C6Fvyml09H4vGTRLlmS2DTITE= X-Received: by 2002:a1f:2145:: with SMTP id h66mr682873vkh.65.1546956595430; Tue, 08 Jan 2019 06:09:55 -0800 (PST) MIME-Version: 1.0 References: <1996329d875e1ab5b9cd69db187b7037ad3a0d8d.camel@perches.com> In-Reply-To: From: Geert Uytterhoeven Date: Tue, 8 Jan 2019 15:09:42 +0100 Message-ID: Subject: Re: [PATCH] Raise the minimum required gcc version to 4.6 To: Joe Perches Cc: "torvalds@linux-foundation.org" , Linux Kernel Mailing List , Andrew Morton , Dave Hansen , Mike Galbraith , Guenter Roeck , Rik van Riel , Kees Cook , Nick Desaulniers , Jonathan Corbet , "open list:DOCUMENTATION" , Arnd Bergmann , linux-m68k Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Dec 29, 2018 at 3:25 PM Geert Uytterhoeven wrote: > On Fri, Aug 24, 2018 at 12:00 AM Joe Perches wrote: > > On Thu, 2018-08-23 at 23:52 +0200, Geert Uytterhoeven wrote: > > > Reverted locally (incl. the follow-up), applied Andrew's fix, detected new > > > warnings in v4.18+, and sent patches where it makes sense... > > > > Thanks for that. > > Given the rise of anonymous unions all over the place, I gave up, and > have upgraded from gcc 4.1.2 to 7.3.0 for cross-compiling m68k kernels. > One good things is that the kernel size for an atari_defconfig kernel dropped > by 3.7% or 163 KiB. > > For the record, below is a list of differences in generated warnings. > Note that the source trees are not identical, as the tree used with > gcc-7.3.0 did not include any workarounds I needed for gcc-4.1.2. > All warnings flagged by gcc 4.1.2 should be false positives (iff I did a > good job during the last few years ;-) > > I plan to repeat the exercise with gcc-8.2.0 (after v4.21-rc1 or so). As promised, gcc-7.3.0 => gcc-8.2.0: *** ERRORS *** 4 error regressions: + error: devfreq.c: undefined reference to `strcmp': => .text+0x9c6) + error: ldm.c: undefined reference to `strcmp': => .text+0x1900), .text+0x1964), .text+0x19a0), .text+0x193c) + error: proc.c: undefined reference to `strcmp': => .text+0x18c), .text+0x178) + error: xattr.c: undefined reference to `strcmp': => .text+0xbaa), .text+0xbf0), .text+0x2e8), .text+0x268), .text+0x97a), .text+0x9be), .text+0x3d4) Hmm, time to fix the auto-strncmp-to-strcmp-conversion for good... *** WARNINGS *** 1 warning regressions: + drivers/dio/dio.c: warning: ‘strcpy’ writing 69 or more bytes into a region of size 64 overflows the destination [-Wstringop-overflow=]: => 240:17 That's a nice one, it found a 15 year old bug. Patch sent ;-) Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds