Squid 3.4.9 - core dumped when shutting down

[Dr. Peter Voigt]

After my recent upgrade to 10.1-RELEASE (amd64) have have rebuilt all
ports. At the end of this proces I rebooted the machine and saw a

pid <pid> (squid), uid 100: exited on signal 6 (core dumped)

message in the kernel log. This behavior of Squid is reproducible on
every shutdown of Squid, e.g.

# service squid stop

produces a core dump /var/cache/squid/squid.core. Moreover, squid is
not cleanly terminated leaving one process which must be killed
manually with 

# kill <pid>

After that Squid can be started normally and it will run rock stable,
e.g. core dumping is occuring only when Squid is terminated.

I am wondering if this is a 10.1-RELEASE related issue or not. I have
not 10.0-RELEASE or 9.x-RELEASE available to check.

I necessary, I can provide some more information, e.g. the remaining
process list of Squid after a shutdown attempt and the squid.core file.

My exact Squid version is:

# pkg version |grep squid
squid-3.4.9_1                      =
squidGuard-1.4_15                  =
squidclamav-6.10_2                 =

Regards,
Peter