[Bug tree-optimization/31169] Bootstrap comparison error at revision 122821

["rguenth at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

------- Comment #32 from rguenth at gcc dot gnu dot org  2007-03-28 08:52 -------
There is

  /* Refuse to operate on VARYING ranges, ranges of different kinds
     and symbolic ranges.  As an exception, we allow BIT_AND_EXPR
     because we may be able to derive a useful range even if one of
     the operands is VR_VARYING or symbolic range.  TODO, we may be
     able to derive anti-ranges in some cases.  */  
  if (code != BIT_AND_EXPR
      && code != TRUTH_AND_EXPR
      && code != TRUTH_OR_EXPR
      && (vr0.type == VR_VARYING
          || vr1.type == VR_VARYING
          || vr0.type != vr1.type
          || symbolic_range_p (&vr0)
          || symbolic_range_p (&vr1)))
    {
      set_value_range_to_varying (vr);
      return;
    }

which sets the value range to varying if vr0.type != vr1.type, so if
vr1.type is not an anti-range, then vr0.type isn't either.


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31169