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Date: Tue, 21 Oct 2008 12:30:00 -0000
Subject: [Bug c/37882]  New: [4.3/4.4 Regression] Bitfield miscompilation
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From: "jakub at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org>
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struct S
{
  int a : 21;
  unsigned char b : 3;
} s;

int
main ()
{
  s.b = 4;
  if (s.b > 0 && s.b < 4)
    __builtin_abort ();
  return 0;
}

See http://gcc.gnu.org/ml/gcc-bugs/2008-10/msg01324.html
Works till 4.2, fails at -O with 4.3 and trunk.


-- 
           Summary: [4.3/4.4 Regression] Bitfield miscompilation
           Product: gcc
           Version: 4.4.0
            Status: UNCONFIRMED
          Keywords: wrong-code
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: jakub at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37882