When poudriere built repositories have DEFAULT_OPTIONS+=samba=4.8 set in the poudriere-specific make.conf file, several ports fail to build due to the error: Invalid version of samba: 4.8 Building the port net/pecl-smbclient the classical BSDish way (via make), there is a message, that the requirement of Samba 4.7 is handled bt net/samba48 and the port compiles and successfully installs.
A commit references this bug: Author: timur Date: Thu Apr 12 08:54:30 UTC 2018 New revision: 467131 URL: https://svnweb.freebsd.org/changeset/ports/467131 Log: Add Samba 4.8 as possible default version, remove obsolete Samba 4.4 PR: 227453 Sponsored by: iXsystems Inc. Changes: head/Mk/Uses/samba.mk
Committed, thanks!