From owner-freebsd-stable Fri Oct 27 15:51:35 2000 Delivered-To: freebsd-stable@freebsd.org Received: from mail.wgate.com (mail.wgate.com [38.219.83.4]) by hub.freebsd.org (Postfix) with ESMTP id 6387D37B479 for ; Fri, 27 Oct 2000 15:51:30 -0700 (PDT) Received: from jesup.eng.tvol.net ([10.32.2.26]) by mail.wgate.com with SMTP (Microsoft Exchange Internet Mail Service Version 5.5.2650.21) id VT2X0HJB; Fri, 27 Oct 2000 18:51:35 -0400 Reply-To: Randell Jesup To: Juha Saarinen Cc: Michel Talon , "freebsd-stable@FreeBSD.ORG" Subject: Re: "Malloc type lacks magic" show-stopper solved References: From: Randell Jesup Date: 27 Oct 2000 18:54:50 -0400 In-Reply-To: Juha Saarinen's message of "Sat, 28 Oct 2000 11:19:37 +1300 (NZDT)" Message-ID: User-Agent: Gnus/5.0807 (Gnus v5.8.7) Emacs/20.7 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: owner-freebsd-stable@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Juha Saarinen writes: >> things like PII's than for Athlon/Duron). Removing frame pointers for >> example can save a lot of memory traffic, > >With -fomit-frame-pointer? That doesn't seem to be possible -- if you try >that, you get an error message about "pg" (probably not the right name, >but I can't check that now) not being compatible with >-fomit-frame-pointer. True - profiling code hooks (-pg) aren't compatible with -fomit-frame-pointer. So? If I want to compile a version for profiling the kernel, I'll compile a version for that purpose. >> as can letting the compiler optimize away or merge locals. > >How would you do that, out of interest? The compiler says "look, this variable isn't used again before it's thrown away (or set to another value). I'll reuse the register/stack location it's stored in for another value". Typical result is that when debugging code optimized this way, "dead" variables display as garbage in a debugger. I suspect gcc does that optimization at the -O level. It may do more of it at -O2 or -O3. -- Randell Jesup, Worldgate Communications, ex-Scala, ex-Amiga OS team ('88-94) rjesup@wgate.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message