From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 1766 invoked by alias); 12 Nov 2002 13:06:08 -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 1751 invoked by uid 71); 12 Nov 2002 13:06:06 -0000 Date: Tue, 19 Nov 2002 14:36:00 -0000 Message-ID: <20021112130606.1750.qmail@sources.redhat.com> To: nobody@gcc.gnu.org Cc: gcc-prs@gcc.gnu.org, From: Christoph Ludwig Subject: Re: optimization/8541: Alpha architecture: Wrong code with -O1 and higher (Regression from 2.95) Reply-To: Christoph Ludwig X-SW-Source: 2002-11/txt/msg00579.txt.bz2 List-Id: The following reply was made to PR optimization/8541; it has been noted by GNATS. From: Christoph Ludwig To: Falk Hueffner Cc: gcc-gnats@gcc.gnu.org Subject: Re: optimization/8541: Alpha architecture: Wrong code with -O1 and higher (Regression from 2.95) Date: Tue, 12 Nov 2002 14:00:57 +0100 On Tue, Nov 12, 2002 at 01:01:25PM +0100, Falk Hueffner wrote: > > // a1 * RADIX + a0 = quot * b + RV > inline udigit > divide (udigit & quot, udigit a1, udigit a0, udigit b) > { > udigit a[2] = { a0, a1 }; > return mpn_divrem_1(", 0, a, 2, b); > } > > [...] > udigit accum_l, accum_h, temp_h, temp_l, carry; > [...] > accum_h = divide(carry, 0, accum_h, pp); > > It seems to me that mpn_divrem_1 might write 2 words to carry, > clobbering random stack memory. Are you sure it doesn't? Oops! I added a few further tests, and it seems, you are right. I was looking for the error in the wrong corner of the library. :-( My apologies for the unnecessary noise on the gcc bug mailing list. How do I withdraw a bug report or request it to be closed? Regards Christoph -- http://www.informatik.tu-darmstadt.de/TI/Mitarbeiter/cludwig.html LiDIA-CA: http://www.informatik.tu-darmstadt.de/TI/Forschung/LiDIA-CA/