From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 111924 invoked by alias); 29 Oct 2019 08:45:50 -0000 Mailing-List: contact gcc-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-owner@gcc.gnu.org Received: (qmail 111863 invoked by uid 89); 29 Oct 2019 08:45:48 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-2.5 required=5.0 tests=AWL,BAYES_00,FREEMAIL_FROM,RCVD_IN_DNSWL_NONE,SPF_PASS autolearn=ham version=3.3.1 spammy=shipping X-HELO: mail-lf1-f46.google.com Received: from mail-lf1-f46.google.com (HELO mail-lf1-f46.google.com) (209.85.167.46) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Tue, 29 Oct 2019 08:45:44 +0000 Received: by mail-lf1-f46.google.com with SMTP id t8so9840416lfc.13 for ; Tue, 29 Oct 2019 01:45:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=+CbLDNdSawGZlN2vZ6gpPSDNJExEvePk4Vc3alVSpXE=; b=o/1uttUSuxc3C1GF29MTPHRY5rD+RbdXMLPPn0NGOwaFtTFC9LI7SUB9QeEki8kYZJ C6+X9imf3YDWakhuIK8k+J5Vi9aG/OZ29cto1MbokJhg0+WO5UYeo142kyTY7tC3TJSB zLODl1ROqOFSJQYht7LZL8JACoUPpDcmI+krtsJunwKAZI1Upu/s1lKLYmavxZTzXe4f haWDuAKS1L3oE5la46S+CGqgL5J7bUNdGM2bmaD7m7L8re9lD3aMmBYLCPDE3eh1dSwJ Nnaa/qOE25dWlLjF6Vg0pwlGi32F8VHbIEQQCs8twqUAIOwk/EfqhYItavGTFmeBGLHk QASg== MIME-Version: 1.0 References: <20191028202713.GF28442@gate.crashing.org> <00dcb1c4-793c-c44f-da1b-eabe067c7e1e@redhat.com> <20191028221203.GG28442@gate.crashing.org> In-Reply-To: <20191028221203.GG28442@gate.crashing.org> From: Richard Biener Date: Tue, 29 Oct 2019 08:45:00 -0000 Message-ID: Subject: Re: GCC selftest improvements To: Segher Boessenkool Cc: Jeff Law , Gabriel Dos Reis , Andrew Dean , David Malcolm , "gcc@gcc.gnu.org" , "ro@CeBiTec.Uni-Bielefeld.DE" , "mikestump@comcast.net" , "jason@redhat.com" , Jonathan Wakely Content-Type: text/plain; charset="UTF-8" X-IsSubscribed: yes X-SW-Source: 2019-10/txt/msg00181.txt.bz2 On Mon, Oct 28, 2019 at 11:12 PM Segher Boessenkool wrote: > > On Mon, Oct 28, 2019 at 03:41:13PM -0600, Jeff Law wrote: > > On 10/28/19 2:27 PM, Segher Boessenkool wrote: > > > On Mon, Oct 28, 2019 at 01:40:03PM -0600, Jeff Law wrote: > > >> On 10/25/19 6:01 PM, Gabriel Dos Reis wrote: > > >>> Jason, Jonathan - is the situation on the terrain really that dire that C++11 (or C++14) isn't at all available for platforms that GCC is bootstrapped from? > > >> The argument that I'd make is that's relatively uncommon (I know, I know > > >> AIX) that bootstrapping in those environments may well require first > > >> building something like gcc-9. > > >> > > >> I'd really like to see us move to C++11 or beyond. Sadly, I don't think > > >> we have any good mechanism for making this kind of technical decision > > >> when there isn't consensus. > > > > > > Which GCC version will be required to work as bootstrap compiler? Will > > > 4.8.5 be enough? > > I'd say gcc-9. What would we gain by making it 4.8 or anything else > > that old? > > Many systems do not have a system compiler newer than this *four years old* > one. GCC 4.8 is the first GCC version that supports all of C++11, which is > the only reason it would be even near acceptable to require something this > *new*. Agreed. Note we're even shipping new service packs for SLE12 which has that "ancient" compiler version (OTOH there _is_ a fully supported GCC 9 available for SLE12 as well). So, if we want C++11 then fine. But requiring GCC 9+ isn't going to fly. IIRC GCC 6 is first having -std=c++14 by default, but unless there's a compelling reason to use C++14 in GCC I'd rather not do it at this point. Removing all the workarounds in the tree we have for GCC 4.[12].x would of course be nice. But I have to update the testers that still use GCC 4.1.x as host compiler :P Richard. > > Segher