From owner-freebsd-stable Wed Oct 25 0:10: 6 2000 Delivered-To: freebsd-stable@freebsd.org Received: from shiva.jussieu.fr (shiva.jussieu.fr [134.157.0.129]) by hub.freebsd.org (Postfix) with ESMTP id B87DE37B479 for ; Wed, 25 Oct 2000 00:10:00 -0700 (PDT) Received: from parthe.lpthe.jussieu.fr (parthe.lpthe.jussieu.fr [134.157.10.1]) by shiva.jussieu.fr (8.10.0/jtpda-5.3.3) with ESMTP id e9P79xq21025 for ; Wed, 25 Oct 2000 09:09:59 +0200 (CEST) Received: from rose.lpthe.jussieu.fr ([134.157.10.102]) by parthe.lpthe.jussieu.fr (8.9.1a/jtpda-5.3.1) with ESMTP id JAA19413 for ; Wed, 25 Oct 2000 09:09:59 +0200 (MET DST) Received: (from michel@localhost) by rose.lpthe.jussieu.fr (8.9.3/8.9.3) id JAA00450 for freebsd-stable@FreeBSD.ORG; Wed, 25 Oct 2000 09:09:58 +0200 (CEST) (envelope-from michel) Date: Wed, 25 Oct 2000 09:09:58 +0200 From: Michel Talon To: freebsd-stable@FreeBSD.ORG Subject: Re: "Malloc type lacks magic" show-stopper solved Message-ID: <20001025090958.A435@lpthe.jussieu.fr> Mail-Followup-To: freebsd-stable@FreeBSD.ORG References: <200010250420.e9P4Kwe33361@cwsys.cwsent.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0pre2i In-Reply-To: Sender: owner-freebsd-stable@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Wed, Oct 25, 2000 at 07:45:24PM +1300, Juha Saarinen wrote: > %-> Anything above -O is not recommended. I've had problems with > %-> optimisation above -O under gcc on Intel (FreeBSD & Linux) ever since I > %-> converted from IBM mainframe to UNIX (religious experience). > > Thanks Cy. Still, it beggars the question... "why not?". I've not had any > problems with -O3 on Linux 2.2 and 2.4, and like I said, it worked under > FreeBSD 3.3. > > -- Juha First you don't have the same gcc version number in FreeBSD 3.3 and 4.1 and in Linux. If you read Documentation/Changes in even the most recent Linux kernel (4.0 Test 9) it is explicitly stated that old gcc is recommended over newer ones, and that bugs occur with newer ones. Second, i recommend you to write a program with a significative amount of computations and compile it with all flags possible, -O -O2 -O3 -Os and measure the execution time. You may be surprised. Last time i did that -O was the faster! -- Michel Talon To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message