https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61184
--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
Ok, it's rather an old bug in vrp_operand_equal_p which does
if (is_overflow_infinity (val1))
return is_overflow_infinity (val2);
which isn't correct for how it is called from update_value_range
(old value first, new value last and in this particular case
+INF and +INF(OVF) which are happily classified as equal).
