From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 21664 invoked by alias); 13 Nov 2001 17:26:07 -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 21614 invoked by uid 71); 13 Nov 2001 17:26:02 -0000 Resent-Date: 13 Nov 2001 17:26:02 -0000 Resent-Message-ID: <20011113172602.21613.qmail@sourceware.cygnus.com> Resent-From: gcc-gnats@gcc.gnu.org (GNATS Filer) Resent-To: nobody@gcc.gnu.org Resent-Cc: gcc-prs@gcc.gnu.org, gcc-bugs@gcc.gnu.org Resent-Reply-To: gcc-gnats@gcc.gnu.org, pavenis@latnet.lv Received:(qmail 18598 invoked by uid 61); 13 Nov 2001 17:16:39 -0000 Message-Id:<20011113171639.18597.qmail@sourceware.cygnus.com> Date: Fri, 02 Nov 2001 07:21:00 -0000 From: pavenis@latnet.lv Reply-To: pavenis@latnet.lv To: gcc-gnats@gcc.gnu.org X-Send-Pr-Version:gnatsweb-2.9.2 (1.1.1.1.2.21) Subject: optimization/4867: gcc-3.1 20011112 generates wrong code for integer division X-SW-Source: 2001-11/txt/msg00045.txt.bz2 List-Id: >Number: 4867 >Category: optimization >Synopsis: gcc-3.1 20011112 generates wrong code for integer division >Confidential: no >Severity: serious >Priority: medium >Responsible: unassigned >State: open >Class: wrong-code >Submitter-Id: net >Arrival-Date: Tue Nov 13 09:26:01 PST 2001 >Closed-Date: >Last-Modified: >Originator: Andris Pavenis >Release: gcc-3.1 20011112 (experimental), gcc-3.1 20011030 (experimental) >Organization: >Environment: gcc-3.1 20011112 for i686-pc-linux-gnu, gcc-3.1 20011030 for i586-pc-msdosdjgpp >Description: gcc-3.1 generates bad code for integer division and taking remainder when result is being stored in structure members which size is specified in bits (8 bits in this case) in included example. It happens for -march=i386, -march=i486, -march=i586 and -march=k6, but not for -march=i686. I'm getting output: 245 19 instead of correct: 42 1 Andris #include struct foo { unsigned a:8, b:8; }; struct foo div10 (unsigned short arg); int main (void) { struct foo bar = div10(421); printf ("%u %u\n", (unsigned) bar.a, (unsigned) bar.b); } struct foo div10 (unsigned short arg) { struct foo bar; bar.a = arg/10; bar.b = arg%10; return bar; } >How-To-Repeat: gcc -O2 -march=i386 foo.c -o foo ./foo (the same for i486, i586 and k6). >Fix: >Release-Note: >Audit-Trail: >Unformatted: