https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103008
--- Comment #11 from joseph at codesourcery dot com <joseph at codesourcery dot com> --- An implementation using division like that definitely isn't valid without -funsafe-math-optimizations (it gives nonsense results when the exponent difference between the arguments is too large, inaccurate results whenever the multiplication is inexact unless you use fma, and spurious exceptions for operations that are never supposed to raise "inexact" on any arguments).