Memory leaks when using printf date/time formatting with user supplied date/time

[tiny28]

The following loop that makes use of the shell's builtin printf date/time formatting causes a slow memory leak.
The offending bit seems to be the second printf statement which parses a user specified date/time

while sleep 0.01s; do
printf -v date '%(%K.%3N)T'
printf -v jday '%(%j)T' "${date}"
done

Showing memory growth over time. $PID is set to the pid of the backgrounded script containing the loop.

while kill -0 $PID 2>/dev/null; do
ps -p $PID -o pid,vsz,rss,comm --no-headers
sleep 1
done

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