From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 4845 invoked by alias); 23 Apr 2002 19:56:03 -0000 Mailing-List: contact gcc-prs-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Archive: List-Post: List-Help: Sender: gcc-prs-owner@gcc.gnu.org Received: (qmail 4800 invoked by uid 71); 23 Apr 2002 19:56:02 -0000 Date: Tue, 23 Apr 2002 12:56:00 -0000 Message-ID: <20020423195601.4795.qmail@sources.redhat.com> To: echristo@gcc.gnu.org Cc: gcc-prs@gcc.gnu.org, From: Eric Christopher Subject: RE: libstdc++/5625: exception unwinding creates invalid pointer o n mips Reply-To: Eric Christopher X-SW-Source: 2002-04/txt/msg01217.txt.bz2 List-Id: The following reply was made to PR libstdc++/5625; it has been noted by GNATS. From: Eric Christopher To: Ed Maste Cc: "'echristo@gcc.gnu.org'" , "'gcc-bugs@gcc.gnu.org'" , "'gcc-prs@gcc.gnu.org'" , "'gcc-gnats@gcc.gnu.org'" Subject: RE: libstdc++/5625: exception unwinding creates invalid pointer o n mips Date: 23 Apr 2002 12:44:46 -0700 On Tue, 2002-04-23 at 12:35, Ed Maste wrote: > Yes, the MIPS documentation states that the destination register > gets the sign-extended result ("GPR[rt]<-sign_extend(temp31..0)"). > > However, note the ADDIU instruction Restrictions section: > > Restrictions: > If GPR rs does not contain a sign-extended > 32-bit value (bits 63..31 equal), then the > result of the operation is UNPREDICTABLE. > So it sounds like both your processor and gcc are in error. gcc by not sign extending the value before and you for not sign extending it after. I'll take a look at the sign extension requirements in the back end. -eric -- A fire drill does not demand a fire.