From owner-freebsd-hackers Wed Jan 5 10:45:18 2000 Delivered-To: freebsd-hackers@freebsd.org Received: from dan.emsphone.com (dan.emsphone.com [199.67.51.101]) by hub.freebsd.org (Postfix) with ESMTP id 658BC15486 for ; Wed, 5 Jan 2000 10:45:08 -0800 (PST) (envelope-from dan@dan.emsphone.com) Received: (from dan@localhost) by dan.emsphone.com (8.9.3/8.9.3) id MAA31309; Wed, 5 Jan 2000 12:44:40 -0600 (CST) (envelope-from dan) Date: Wed, 5 Jan 2000 12:44:40 -0600 From: Dan Nelson To: "Ronald F. Guilmette" Cc: Martin Cracauer , mauzi@poli.hu, hackers@FreeBSD.ORG Subject: Re: [OFFTOPIC] alt. C compiler Message-ID: <20000105124439.A28602@dan.emsphone.com> References: <20000105100909.B63545@cons.org> <99736.947095986@monkeys.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0i In-Reply-To: <99736.947095986@monkeys.com>; from "Ronald F. Guilmette" on Wed Jan 5 10:13:06 GMT 2000 X-OS: FreeBSD 4.0-CURRENT Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG In the last episode (Jan 05), Ronald F. Guilmette said: > Martin Cracauer wrote: > > > >When your code breaks when using -O2 or higher, don't do that, use > >just -O! > > Ah, excuse me, but -O is equivalent to -O2. /usr/src/contrib/gcc/toplev.c:4821 if (!strcmp (argv[i], "-O")) { optimize = 1; optimize_size = 0; } So, -O is equivalent to -O1. Go down one page from there, and you'll see the individual optiomizations enabled by each level. Also note that for stock gcc, there is nothing above -O3 (If you see someone using anything higher, you can be sure they're using pgcc). The -Os flag automatically sets -O2. -- Dan Nelson dnelson@emsphone.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message