Why was rsyslog.log created by valgrind automatically deleted?

Issue

• Following valgrind command was executed on the system to log the output at /tmp/rsyslog.log:

# service rsyslog stop
# /usr/bin/valgrind --trace-children=yes --show-reachable=yes --track-origins=yes --read-var-info=yes --tool=memcheck --leak-check=full --num-callers=50 -v --log-file=/tmp/rsyslog.log /sbin/rsyslogd -i /var/run/syslogd.pid -c 5

• But /tmp/rsyslog.log no longer exists.
• Does valgrind delete the log file it is stopped or terminated?