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 A296AC4321D for ; Thu, 23 Aug 2018 21:52:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4807920661 for ; Thu, 23 Aug 2018 21:52:55 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4807920661 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-m68k.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728332AbeHXBYd (ORCPT ); Thu, 23 Aug 2018 21:24:33 -0400 Received: from mail-ua1-f65.google.com ([209.85.222.65]:38895 "EHLO mail-ua1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726458AbeHXBYc (ORCPT ); Thu, 23 Aug 2018 21:24:32 -0400 Received: by mail-ua1-f65.google.com with SMTP id o11-v6so4177846uak.5; Thu, 23 Aug 2018 14:52:52 -0700 (PDT) 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; bh=YFwoNoEPmLbe8W2YiVMYx5Z3YR1vK+8c/BzXFqQ8EeM=; b=IbAVC6/wweH15JdJ2B/qJ9MnbXDmHtBxytm3P6/sB4aIc6e9ctnphVocYqYFsFgiCz 3AcQTDWY+vPRuKpdXK/dOUbuTVYaOgGhShodEPXt1KWyey3Mt2IsnDH47H5/bCOUHLaC Gjk/HdLU0gkcpBlEVVy9NXe7Y3Y3cnNJZ6Oawd+UoRmqsjjQy5T2mU1/3YyZFmgvIPy0 t6Wn3aFEdoRqLT6+I+pItRjQrLLDY+DgGewlzkUaRjuJ+IRqJRHY4Sc8FFvh4CqGUap2 jPQW9Qsc2uN+an9udPuTNyNrXTENDhM8c9ZDZnBjteTRD6TCu38YnSQFSKFC+xbbiuJx 1X3w== X-Gm-Message-State: APzg51CQ6mNMFO9D27FfdBA5o8lknp3twuINoC4JrgOkLjXrxLJu5jNI 8CJADgzqP2beRscS4Yx/XnOBFzyclPAI7tIcVms= X-Google-Smtp-Source: ANB0VdZKwDzx0n6Go+YCvcjB6M3WicGa58lXfS4tT+BczHBKHyVPk4SY8RGyfOqesxapxDC4Q1pCU2wRnh020Xy3spw= X-Received: by 2002:ab0:51e4:: with SMTP id h33-v6mr6033949uaa.137.1535061172085; Thu, 23 Aug 2018 14:52:52 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Geert Uytterhoeven Date: Thu, 23 Aug 2018 23:52:40 +0200 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 , riel@surriel.com, Kees Cook , Nick Desaulniers , Jonathan Corbet , "open list:DOCUMENTATION" , Arnd Bergmann Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Joe, On Mon, Aug 20, 2018 at 10:15 PM Joe Perches wrote: > Various architectures fail to build properly with older versions > of the gcc compiler. > > An example from Guenter Roeck via this thread: > https://lore.kernel.org/lkml/20180814170904.GA12768@roeck-us.net/ > > ---------------------- > In file included from ./include/linux/mm.h:17:0, > from ./include/linux/pid_namespace.h:7, > from ./include/linux/ptrace.h:10, > from arch/openrisc/kernel/asm-offsets.c:32: > ./include/linux/mm_types.h:497:16: error: flexible array member in otherwise empty struct > > This is just an example with gcc 4.5.1 for or32. I have seen the problem > with gcc 4.4 (for unicore32) as well. > ---------------------- > > So update the minimum required version of gcc to 4.6. > > Miscellanea: > > o Update Documentation/process/changes.rst > o Remove and consolidate version test blocks in compiler-gcc.h > for versions lower than 4.6 > > Signed-off-by: Joe Perches > Reviewed-by: Kees Cook > Reviewed-by: Nick Desaulniers Thanks for your patch! I'm willing to upgrade. But there's one thing that's holding me back. Does gcc 8.x gives again the same warnings as my venerable old gcc 4.1.2, that no one else seems to see? Or will the real bugs I detect this way stay unfixed? Polyculture is a good thing, also in compilers. Reverted locally (incl. the follow-up), applied Andrew's fix, detected new warnings in v4.18+, and sent patches where it makes sense... 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