This blog is updated daily.
A general description is here.
Error messages involving non-syntactic names (e.g. as produced by ‘`\r`’ when that object does not exist) now encode the control characters. (Reported by Hadley Wickham.)
On system where ‘mktime()’ does not set ‘ERRNO’, the last second before the epoch could not be converted from ‘POSIXlt’ to ‘POSIXct’. (Reported by Bill Dunlap.)