Failsafe_flags : where invalid values update?

Hello dear,

I am developing using PX4 autopilot v1.15.4.

I looked for where the various invalid values ​​of failsafe_flags (ex. angular_velocity_invalid) are updated, but I couldn’t find any point where they are updated other than HealthAndArmingChecks where they are initialized to true.

Are these values ​​just dummy values, or am I just missing something?