Leaping seconds and looping servers

You completely ignored everything I mentioned about filesystems, networking, the intersection of the two, and other routes for times out of the kernel which do not pass through glibc (or, if they do,. Since this is the nub of the problem, requiring replication of rarely-tested TAI-to-UTC conversion code in many places where it is currently centralized in two (NTP and the kernel), it is not surprising that you thought there was no real problem. There is.