On FreeBSD 10.3 gimp can cause the following error.

(script-fu:3985): LibGimp-ERROR **: shmat() failed: Invalid argument
Could not attach to gimp shared memory segment

This can be fixed by setting kern.ipc.shm_allow_removed=1 in /etc/sysctl.conf.
FreeBSD 11.0-R and newer have this set by default.