Meanwhile I checked the upstream history on github, and it appears the comma wasn't missing in the initial commit, but got lost in the next commit in file garb/garb_config.cpp.
Initial commit with the comma: https://github.com/codership/galera/commit/29d906e6239e0a4111214a8bf7f0779308f479f8 Comma lost somehow (I can't explain it. Manual resolution of a merge going wrong?) in the next commit: https://github.com/codership/galera/commit/b3c498328b699c733e5c881fcc66a6f721ac674d I aligned with this and put the comma exactly at the same place as the initial commit (instead of my previous patch) in the M.R below: https://salsa.debian.org/mariadb-team/galera-4/-/merge_requests/30 Tested OK with and without using the WORK_DIR parameter. regards, Adel Belhouane.