From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugs-return-388895-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org>
Received: (qmail 19426 invoked by alias); 15 Apr 2012 14:59:54 -0000
Received: (qmail 19410 invoked by uid 22791); 15 Apr 2012 14:59:52 -0000
X-SWARE-Spam-Status: No, hits=-3.3 required=5.0	tests=ALL_TRUSTED,AWL,BAYES_00,SUBJ_OBFU_PUNCT_FEW,SUBJ_OBFU_PUNCT_MANY
X-Spam-Check-By: sourceware.org
Received: from localhost (HELO gcc.gnu.org) (127.0.0.1)    by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Sun, 15 Apr 2012 14:59:40 +0000
From: "regehr at cs dot utah.edu" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/52996] New: ice in verify_loop_structure, at cfgloop.c:1567
Date: Sun, 15 Apr 2012 14:59:00 -0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: new
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: c
X-Bugzilla-Keywords:
X-Bugzilla-Severity: normal
X-Bugzilla-Who: regehr at cs dot utah.edu
X-Bugzilla-Status: UNCONFIRMED
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org
X-Bugzilla-Target-Milestone: ---
X-Bugzilla-Changed-Fields:
Message-ID: <bug-52996-4@http.gcc.gnu.org/bugzilla/>
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
Content-Type: text/plain; charset="UTF-8"
MIME-Version: 1.0
Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm
Precedence: bulk
List-Id: <gcc-bugs.gcc.gnu.org>
List-Archive: <http://gcc.gnu.org/ml/gcc-bugs/>
List-Post: <mailto:gcc-bugs@gcc.gnu.org>
List-Help: <mailto:gcc-bugs-help@gcc.gnu.org>
Sender: gcc-bugs-owner@gcc.gnu.org
X-SW-Source: 2012-04/txt/msg01177.txt.bz2

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52996

             Bug #: 52996
           Summary: ice in verify_loop_structure, at cfgloop.c:1567
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: regehr@cs.utah.edu
                CC: chenyang@cs.utah.edu


[regehr@dyson r33]$ current-gcc -O3 -c small.c
small.c: In function 'fn1':
small.c:29:1: error: edge from 18 to 19 should be marked irreducible
 }
 ^
small.c:29:1: error: basic block 19 should be marked irreducible
 }
 ^
small.c:29:1: error: edge from 19 to 11 should be marked irreducible
 }
 ^
small.c:29:1: internal compiler error: in verify_loop_structure, at
cfgloop.c:1567
 }
 ^
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.


[regehr@dyson r33]$ cat small.c
int a, b, c, d, e, f;
void
fn1 ()
{
    int g, h;
lbl_173:
    if (a)
        c++;
lbl_158:
    e = 0;
    h = 0;
    for (; h > -8; h--)
    {
        g = 0;
        for (; g <= 0; g += 1)
        {
            d = 1;
            for (; d >= 0; d -= 1)
                a = 1;
            if (b)
                break;
            if (f)
                return;
            if (h)
                goto lbl_158;
        }
    }
    goto lbl_173;
}


[regehr@dyson r33]$ current-gcc -v
Using built-in specs.
COLLECT_GCC=current-gcc
COLLECT_LTO_WRAPPER=/uusoc/exports/scratch/regehr/z/compiler-install/gcc-r186455-install/bin/../libexec/gcc/x86_64-unknown-linux-gnu/4.8.0/lto-wrapper
Target: x86_64-unknown-linux-gnu
Configured with: ../configure --with-libelf=/usr/local --enable-lto
--prefix=/home/regehr/z/compiler-install/gcc-r186455-install
--program-prefix=r186455- --enable-languages=c,c++
Thread model: posix
gcc version 4.8.0 20120414 (experimental) (GCC)