https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78257
--- Comment #3 from Martin Liška <marxin at gcc dot gnu.org> --- 'f0' function is optimized out as of r242000
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78257
--- Comment #3 from Martin Liška <marxin at gcc dot gnu.org> --- 'f0' function is optimized out as of r242000