Re: PATCH COMMITTED: gcc 4.2 support for -Wstrict-overflow/-fstrict-overflow

[Ian Lance Taylor <iant at google dot com>]

"Richard Guenther" <richard.guenther@gmail.com> writes:

> I didn't notice it flushed to varying.  It does so for wrapping semantics
> (but I have patches to improve this), not for undefined overflow
> semantics.  So I think these cases are unchanged with your patch.

I mean these lines in extract_range_from_binary_expr (this is the
version from before my patch):

  if (!is_gimple_min_invariant (min) || TREE_OVERFLOW (min)
      || !is_gimple_min_invariant (max) || TREE_OVERFLOW (max))
    {
      set_value_range_to_varying (vr);
      return;
    }

Those lines are now:

  if (min == NULL_TREE
      || !is_gimple_min_invariant (min)
      || (TREE_OVERFLOW (min) && !is_overflow_infinity (min))
      || max == NULL_TREE
      || !is_gimple_min_invariant (max)
      || (TREE_OVERFLOW (max) && !is_overflow_infinity (max)))
    {
      set_value_range_to_varying (vr);
      return;
    }

Ian