From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from baldric (baldric.uwo.ca [129.100.10.225]) by dsl2.external.hp.com (Postfix) with ESMTP id 7C18D483E for ; Sun, 21 Sep 2003 13:19:13 -0600 (MDT) Date: Sun, 21 Sep 2003 15:16:53 -0400 From: Carlos O'Donell To: John David Anglin Cc: dave.anglin@nrc-cnrc.gc.ca, parisc-linux@lists.parisc-linux.org Subject: Re: [parisc-linux] Re: Found the r19 problem! Message-ID: <20030921191653.GJ6963@systemhalted> References: <20030921185531.GH6963@systemhalted> <200309211912.h8LJCd59011386@hiauly1.hia.nrc.ca> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <200309211912.h8LJCd59011386@hiauly1.hia.nrc.ca> Sender: parisc-linux-admin@lists.parisc-linux.org Errors-To: parisc-linux-admin@lists.parisc-linux.org List-Help: List-Post: List-Subscribe: , List-Id: parisc-linux developers list List-Unsubscribe: , List-Archive: On Sun, Sep 21, 2003 at 03:12:39PM -0400, John David Anglin wrote: > Well that's why the restore is deleted. So, the clobber must go > and r19 must be preserved across the asm(...). As I said, you can't > clobber r19 when generating pic code. It's treated as fixed register, > so clobbering it can lead to undefined behavior. > > If the syscall used r19, it could include a use of r19 in the asm. > This would ensure the restore occurs before the syscall. I'm going to stop writing r19 to the stack and tell gcc I'm using r4, and then do a copy/copy to get r19 back. c.