Date: Mon, 15 Mar 2004 02:10:52 +0200 From: Nikos Ntarmos <ntarmos@ceid.upatras.gr> To: freebsd-current@freebsd.org Subject: [ntarmos@ceid.upatras.gr: GCC optimization bugs -- still there or a historic artifact?] Message-ID: <20040315001052.GA20921@diogenis.ceid.upatras.gr>
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--YZ5djTAD1cGYuMQK Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Hi all. I'm crossposting this to current@, as I think it pertains more to 5.2+ and -CURRENT than to hackers@. Cheers... \n\n -- Nikos "Noth" Ntarmos | < ntarmos at ceid dot upatras dot gr > NetCINS Lab. @ C.E.I.D. | [ http://{noth,p2p}.ceid.upatras.gr/ ] U. of Patras - Greece | ( 38.2594N, 21.7428E ) ( 1024D / CF95160A ) --YZ5djTAD1cGYuMQK Content-Type: message/rfc822 Content-Disposition: inline Return-Path: <owner-freebsd-hackers@freebsd.org> X-Original-To: ntarmos@localhost Delivered-To: ntarmos@localhost Received: from localhost (localhost.localdomain [127.0.0.1]) by Noth.ceid.upatras.gr (Postfix) with ESMTP id 24445FBB1 for <ntarmos@localhost>; Sat, 13 Mar 2004 21:50:07 +0200 (EET) Received: from Noth.ceid.upatras.gr ([127.0.0.1]) by localhost (Noth [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 14203-01 for <ntarmos@localhost>; Sat, 13 Mar 2004 21:50:06 +0200 (EET) Received: from localhost (localhost.localdomain [127.0.0.1]) by Noth.ceid.upatras.gr (Postfix) with ESMTP id ED468FD97 for <ntarmos@localhost>; Sat, 13 Mar 2004 21:50:05 +0200 (EET) Delivered-To: ntarmos@ceid.upatras.gr Received: from diogenis.ceid.upatras.gr [150.140.141.181] by localhost with IMAP (fetchmail-6.2.5) for ntarmos@localhost (single-drop); Sat, 13 Mar 2004 21:50:05 +0200 (EET) Received: (qmail 4914 invoked from network); 13 Mar 2004 19:40:57 -0000 Received: from mx2.freebsd.org (216.136.204.119) by diogenis.ceid.upatras.gr with SMTP; 13 Mar 2004 19:40:57 -0000 Received: from hub.freebsd.org (hub.freebsd.org [216.136.204.18]) by mx2.freebsd.org (Postfix) with ESMTP id 657B556D5E; Sat, 13 Mar 2004 11:39:57 -0800 (PST) (envelope-from owner-freebsd-hackers@freebsd.org) Received: from hub.freebsd.org (localhost [127.0.0.1]) by hub.freebsd.org (Postfix) with ESMTP id 7C03416A51F; Sat, 13 Mar 2004 11:39:50 -0800 (PST) Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 1F73516A4CE for <freebsd-hackers@freebsd.org>; Sat, 13 Mar 2004 11:23:26 -0800 (PST) Received: from diogenis.ceid.upatras.gr (diogenis.ceid.upatras.gr [150.140.141.181]) by mx1.FreeBSD.org (Postfix) with SMTP id C7BC143D45 for <freebsd-hackers@freebsd.org>; Sat, 13 Mar 2004 11:23:24 -0800 (PST) (envelope-from ntarmos@Noth.ceid.upatras.gr) Received: (qmail 16252 invoked from network); 13 Mar 2004 19:23:21 -0000 Received: from noth.ceid.upatras.gr (150.140.143.234) by diogenis.ceid.upatras.gr with SMTP; 13 Mar 2004 19:23:21 -0000 Received: from localhost (localhost.localdomain [127.0.0.1]) by Noth.ceid.upatras.gr (Postfix) with ESMTP id 287E6FD97 for <freebsd-hackers@freebsd.org>; Sat, 13 Mar 2004 21:23:58 +0200 (EET) Received: from Noth.ceid.upatras.gr ([127.0.0.1]) by localhost (Noth [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 29604-10 for <freebsd-hackers@freebsd.org>; Sat, 13 Mar 2004 21:23:57 +0200 (EET) Received: by Noth.ceid.upatras.gr (Postfix, from userid 1000) id 956D7FD89; Sat, 13 Mar 2004 21:23:57 +0200 (EET) Date: Sat, 13 Mar 2004 21:23:57 +0200 From: Nikos Ntarmos <ntarmos@ceid.upatras.gr> To: freebsd-hackers@freebsd.org Message-ID: <20040313192357.GA10778@diogenis.ceid.upatras.gr> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.5.1+cvs20040105i X-Virus-Scanned: by amavisd-new-20030616-p7 (Debian) at Noth.ceid.upatras.gr Subject: GCC optimization bugs -- still there or a historic artifact? X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Technical Discussions relating to FreeBSD <freebsd-hackers.freebsd.org> List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-hackers>, <mailto:freebsd-hackers-request@freebsd.org?subject=unsubscribe> List-Archive: <http://lists.freebsd.org/pipermail/freebsd-hackers>; List-Post: <mailto:freebsd-hackers@freebsd.org> List-Help: <mailto:freebsd-hackers-request@freebsd.org?subject=help> List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-hackers>, <mailto:freebsd-hackers-request@freebsd.org?subject=subscribe> Sender: owner-freebsd-hackers@freebsd.org Errors-To: owner-freebsd-hackers@freebsd.org X-Virus-Scanned: by amavisd-new-20030616-p7 (Debian) at Noth.ceid.upatras.gr X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on Noth.ceid.upatras.gr X-Spam-Level: X-Spam-Status: No, hits=-103.4 required=7.0 tests=AWL,BAYES_00, USER_IN_WHITELIST autolearn=ham version=2.63 Hi all. There was a thread on the CFLAGS knob in make.conf in early Feb.'04 (the exact subject was "need help on CFLAGS in /etc/make.conf please"), where some posters raised the issue of gcc optimization bugs that supposedly manifest in optimization levels above -O2. The last post on this subject was on Feb. 13th, though, and nothing has come up ever since. AFAIK 5.2.1+ and -CURRENT have moved to gcc-3.3.3. Are these issues still there? I've been making my way around FreeBSD's and GCC's gnat and couldn't find anything relevant. Ummm... Actually almost all relevant entries in our gnat end with something like "bug the gcc guys for we're too overwhelmed to look into gcc issues". The funny thing is there is no entry in the gcc's gnat about optimization bugs in 3.3.3. As some very specific person noted, "-O gets about an order of magnitude less testing than -O2" by the gcc community. This whole thing came up in the port-alpha@netbsd list, in a thread about Compaq's C compiler (aka ccc) for linux/alpha (lang/compaq-cc in our ports tree) and its status in NetBSD. The manpage for make.conf states that the issues with levels >1 are even worse on alpha. Well, gcc-3.3.3 is as fast as (if not faster than) ccc for optimization levels above -O2, and can be used for a much wider part of the C/C++ source available out there. So the question is: are these gcc issues still there or just a historic artifact left lurking around manpages "just to be sure"? \n\n -- Nikos "Noth" Ntarmos | < ntarmos at ceid dot upatras dot gr > NetCINS Lab. @ C.E.I.D. | [ http://{noth,p2p}.ceid.upatras.gr/ ] U. of Patras - Greece | ( 38.2594N, 21.7428E ) ( 1024D / CF95160A ) _______________________________________________ freebsd-hackers@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to "freebsd-hackers-unsubscribe@freebsd.org" --YZ5djTAD1cGYuMQK--
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