What Parameter To Set To Avoid Crash During GPS Glitch Problem or Bad GPS? Please Help

As we know that some times during flying it may happen GPS glitch or bad Gps. So my question is how to anticipate this GPS issue?? What parameter to set to avoid crash if this problem occur ? What happen if this problem occur during Auto mission. To my knowledge we can set Quadplane to change mode to QHOVER (or Altitude Hold for Copter). But which parameters that control this Gps issue?? What is the best procedure to handle this issue? Thank you.