Constant nc::TIME_UPTIME_SEC_MAX

pub const TIME_UPTIME_SEC_MAX: i64

Located here for timespec[64]_valid_strict Limits for settimeofday():

To prevent setting the time close to the wraparound point time setting is limited so a reasonable uptime can be accomodated. Uptime of 30 years should be really sufficient, which means the cutoff is 2232. At that point the cutoff is just a small part of the larger problem.