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 5BED0C10F13 for ; Thu, 11 Apr 2019 10:18:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3612D20818 for ; Thu, 11 Apr 2019 10:18:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726644AbfDKKSv (ORCPT ); Thu, 11 Apr 2019 06:18:51 -0400 Received: from mail-qt1-f196.google.com ([209.85.160.196]:33736 "EHLO mail-qt1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726026AbfDKKSu (ORCPT ); Thu, 11 Apr 2019 06:18:50 -0400 Received: by mail-qt1-f196.google.com with SMTP id k14so6442300qtb.0; Thu, 11 Apr 2019 03:18:50 -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=0DHhgBXQ0z77tvZpUH6fOOpqgWzNNEa0UaCE/Q5ZlQE=; b=meZe+6e8naF5ZEwaoSbUIs9VlcvP55hQaDlWcY3U6s9f5qhf0oXLxF5/MIhMSjASO9 fbJVKZ5cRCWo2WPuvAh0fBu7DA2BV9uy0/MsLvRUOsfU9RqZqyHD1W/gz88nZWHRt8U0 fE02LDqqRRAXeF1WFOi1H6lyTXQ7rU7Ik0yAe4uzI1+Uyz9eHDOZUTL/ofEnDVDx5ANg ELEiEdseVMCCT0RDJ1PvYDdcF79B52KXJJGQwR3iawZfmh3JFA0G/nq8TQAnWG1ndfVH ZTJgKA0Rb3bSDfngKgpqNXb1XCSwu2mJ78aEjHlAPxI48I1jr4Vphsx08nwXcIaWrGMv 2UaQ== X-Gm-Message-State: APjAAAX/GG5jgsoDrCEVZuIcbhtVB9vvzxaDyfufEYQj9Q7IGY04B4IO QNROK1FprVoNsmb8+/cB8jKUjLZRwD8fzulnLK4= X-Google-Smtp-Source: APXvYqzxGzPRVsikYtH/R8v51echGOnwOUuchObZERN7Vqz5/vGF176FNxASc8nu9q2YfppJz5wcv3MpttbK5iZf108= X-Received: by 2002:a0c:e014:: with SMTP id j20mr38802961qvk.172.1554977929444; Thu, 11 Apr 2019 03:18:49 -0700 (PDT) MIME-Version: 1.0 References: <20190410201300.3528984-1-arnd@arndb.de> In-Reply-To: From: Arnd Bergmann Date: Thu, 11 Apr 2019 12:18:33 +0200 Message-ID: Subject: Re: [PATCH 1/2] s390: only build for new CPUs with clang To: Nick Desaulniers Cc: Martin Schwidefsky , Heiko Carstens , Vasily Gorbik , clang-built-linux@googlegroups.com, Nathan Chancellor , linux-s390 , Masahiro Yamada , Philipp Rudo , Tony Krowiak , LKML 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 On Thu, Apr 11, 2019 at 12:20 AM 'Nick Desaulniers' via Clang Built Linux wrote: > > On Wed, Apr 10, 2019 at 1:13 PM Arnd Bergmann wrote: > > > > llvm does does not understand -march=z9-109 and older target > > Please file bugs for these in LLVM's issue tracker. It might be > possible to enable these additional architecture variants if they're > similar to existing ones and simply unrecognized. IIRC, we had this > issue with armv7 variants. I really don't see that as necessary here. While generally speaking, it would be nice to support the widest possible range of hardware, and it would not be hard to add this support, it seems highly unlikely that anyone would actually want to use that in case of s390. The last enterprise distros to support z9 were SLES11 (end of life as of last month) and RHEL6 (ending its 10 year life next year). Anyone who is still on those releases will probably not install a brand new compiler, and anyone who is on newer releases won't run on prehistoric hardware. Debian still runs on very old hardware in theory, but even there you'd have a hard time finding someone to test the output of the compiler on an old machine. Arnd