cpp/chrono/utc clock/to sys

Converts a  to a  representing the same point in time (if possible).

If represents a time point during a leap second insertion, the last representable value of  prior to the insertion of the leap second is returned. In all other cases,.

Return value
A representing the same point in time as, or the last representable value prior to the insertion of the leap second if  represents a time point during a leap second insertion.