[Bug middle-end/123826] folding of `pow(a, 2.0)` into a*a causes errno not to be set

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123826

--- Comment #12 from Richard Biener <rguenth at gcc dot gnu.org> ---
You can always use -fno-math-errno