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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/46491] New: [4.3/4.4/4.5 Regression] ipa-pure-const.c miscompilation
Date: Mon, 15 Nov 2010 20:04:00 -0000	[thread overview]
Message-ID: <bug-46491-4@http.gcc.gnu.org/bugzilla/> (raw)

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46491

           Summary: [4.3/4.4/4.5 Regression] ipa-pure-const.c
                    miscompilation
           Product: gcc
           Version: 4.5.2
            Status: UNCONFIRMED
          Keywords: wrong-code
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: jakub@gcc.gnu.org
        ReportedBy: jakub@gcc.gnu.org


extern void abort (void);

__attribute__((noinline)) int
foo (int *p)
{
  int r;
  asm ("movl $6, (%1)\n\txorl %0, %0" : "=r" (r) : "r" (p) : "memory");
  return r;
}

int
main (void)
{
  int p = 8;
  if ((foo (&p) ? : p) != 6)
    abort ();
  return 0;
}

is miscompiled with -O2 in 4.5 (and with -O2 -fno-ipa-reference in
4.1/4.2/4.3/4.4).


             reply	other threads:[~2010-11-15 20:03 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-11-15 20:04 jakub at gcc dot gnu.org [this message]
2010-11-15 20:03 ` [Bug tree-optimization/46491] " jakub at gcc dot gnu.org
2010-11-15 22:31 ` jakub at gcc dot gnu.org
2010-11-15 22:37 ` jakub at gcc dot gnu.org
2010-11-15 22:45 ` [Bug tree-optimization/46491] [4.3/4.4 " jakub at gcc dot gnu.org
2011-04-07 21:26 ` jakub at gcc dot gnu.org
2011-06-27 10:38 ` [Bug tree-optimization/46491] [4.3 " rguenth at gcc dot gnu.org
2011-06-27 12:21 ` rguenth at gcc dot gnu.org

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