https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83331
Martin Liška <marxin at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |jakub at gcc dot gnu.org, | |marxin at gcc dot gnu.org, | |rguenth at gcc dot gnu.org --- Comment #1 from Martin Liška <marxin at gcc dot gnu.org> --- It's caused by fact that without optimization level std::cbrt (123.456) is optimized in front-end, while std::cbrt (x) not. However I'm not expert about the floating point behavior.