flags |= CLONE_VFORK | CLONE_VM
	}
	if sys.PidFD != nil {
		flags |= CLONE_PIDFD
	}
	// Whether to use clone3.
	if sys.UseCgroupFD || flags&CLONE_NEWTIME != 0 || forceClone3 {
		clone3 = &cloneArgs{
			flags:      uint64(flags),
			exitSignal: uint64(SIGCHLD),
		}
		if sys.UseCgroupFD {
			clone3.flags |= CLONE_INTO_CGROUP
			clone3.cgroup = uint64(sys.CgroupFD)
		}
		if sys.PidFD != nil {

	}

	fd, suffix := prepareCgroupFD(t)

	cmd := testenv.Command(t, exe, "-test.run=^TestUseCgroupFD$")
	cmd.Env = append(cmd.Environ(), "GO_WANT_HELPER_PROCESS=1")
	cmd.SysProcAttr = &syscall.SysProcAttr{
		UseCgroupFD: true,
		CgroupFD:    fd,
	}
	out, err := cmd.CombinedOutput()
	if err != nil {
		if testenv.SyscallIsNotSupported(err) && !errors.Is(err, syscall.EINVAL) {
			// Can be one of: