The command line tool mariabackup always coredump.

# mariabackup --innobackupex --defaults-extra-file=/usr/local/etc/mysql/my.cnf --tmpdir=/tmp/ --user=galera --password=7xC5xDwzdX --socket=/tmp/mysql.sock --galera-info --stream=xbstream /var/backups/mysql/2018-04-24/

Segmentation fault (core dumped)

But if I specify the full path /usr/local/bin/mariabackup, it works well.
I had this issue since version 10.2.10 and am still having it now at 10.2.14.
This caused galera sst to fail.
Not sure if it's a mariadb bug or the way it was built in FreeBSD port.