https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113411
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Ever confirmed|0 |1
Last reconfirmed| |2024-01-16
Status|UNCONFIRMED |NEW
--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
I think it's OK for reals with -fno-rounding-math.
It's valid for integers with or without undefined overflow, the corner
case to consider is
abs(-INT_MAX - 1) * abs (b)
where with undefined overflow the abs() is already invoking undefined
behavior. The problematical multiplication is (-INT_MAX-1) * -1 but
we cannot arrive at this from a defined input. For
abs(a*b)
the problematical input is -INT_MAX - 1 but we can't arrive at that
either (b == 1 with a == -INT_MAX-1 is undefined, b == -1 the same).
