From owner-freebsd-current Wed Mar 15 23:19:29 2000 Delivered-To: freebsd-current@freebsd.org Received: from ns.cvzoom.net (ns.cvzoom.net [208.226.154.2]) by hub.freebsd.org (Postfix) with SMTP id C9A7837BBA0 for ; Wed, 15 Mar 2000 23:19:26 -0800 (PST) (envelope-from dmmiller@cvzoom.net) Received: (qmail 1672 invoked from network); 16 Mar 2000 07:19:24 -0000 Received: from acs-63-85-133-249.cvzoom.net (HELO cvzoom.net) (63.85.133.249) by ns.cvzoom.net with SMTP; 16 Mar 2000 07:19:24 -0000 Message-ID: <38D08ADF.9C28C61E@cvzoom.net> Date: Thu, 16 Mar 2000 02:18:55 -0500 From: Donn Miller X-Mailer: Mozilla 4.72 [en] (X11; I; FreeBSD 5.0-CURRENT i386) X-Accept-Language: en MIME-Version: 1.0 Cc: freebsd-current@freebsd.org Subject: Re: gcc -Os optimisation broken (RELENG_4) References: <38CF48CF.59A100D7@altavista.net> <8ap8qe$hvj$1@bigeye.rhein-neckar.de> <38D08908.C629B55E@gorean.org> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Doug Barton wrote: > Hmm... If I have a PII (Actually celeron 300A) or a PIII, which is > better, 'pentium' or 'pentiumpro'? I would think the latter, but I've > learned not to assume where gcc is concerned. I think that 'pentium' would result in code that isn't as optimized as 'pentiumpro', but I've heard that 'pentium' has a lot less problems. > Also, I have heard conflicting reports as to whether compiling the > kernel/world with optimisations is a good thing. Anyone care to (re)open > that can of worms? I compile my kernel/world with -mpentium -O3 -pipe. The only problem I've seen so far were spurious random reboots that would occur about 2-3 times a month. But, that was last summer, and hasn't happened since. Something else must have been the culprit. (Maybe -current wasn't as stable last summer.) With the aforementioned CFLAGS, I have a pretty reliable and stable system. I've heard that -mpentiumpro can be pretty buggy, and it can actually result in slower code than -mpentium for certain pentium types. I trust plain -mpentium, as it has been very reliable for me, except for some compile-time errors caused by the optimization (Qt). - Donn To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message