PXC-8.0 rsync upgrade issue : wsrep_sst_common: line 383: $1: unbound variable

        2019-03-25T08:31:17.103832Z WSREP_SST: [INFO] Waiting for data-dir through rsync................
        2019-03-25T08:31:18.643574Z WSREP_SST: [DEBUG] Transfer-type determined to be: ist
        2019-03-25T08:31:18.644862Z WSREP_SST: [INFO] ..............rsync completed
        2019-03-25T08:31:18.645540Z WSREP_SST: [INFO] Running post-processing ...........
/dev/shm/qa/pxc80/bin/wsrep_sst_common: line 383: $1: unbound variable
        2019-03-25T08:31:18.649382Z WSREP_SST: [DEBUG] Running mysql_upgrade, schema versions do not match
        2019-03-25T08:31:18.650046Z WSREP_SST: [DEBUG] wsrep schema version expected:8.0.15 datadir:
        2019-03-25T08:31:18.651836Z WSREP_SST: [INFO] Removing the redo logs (older version:0.0.0)
        2019-03-25T08:31:18.660973Z WSREP_SST: [DEBUG] Found the mysqld binary in /dev/shm/qa/pxc80/bin/mysqld
        2019-03-25T08:31:18.667090Z WSREP_SST: [DEBUG] -- Ver 8.0.15-5-31.33-debug for Linux on x86_64 (Percona XtraDB Cluster binary (GPL) 8.0.15-31.33, Revision -debug - UNIV_DEBUG ON)
        2019-03-25T08:31:18.670253Z WSREP_SST: [DEBUG] Found the mysql_upgrade binary in /dev/shm/qa/pxc80/bin/mysql_upgrade
        2019-03-25T08:31:18.674611Z WSREP_SST: [DEBUG] -- Ver 8.0.15-5-31.33 for Linux on x86_64 (Percona XtraDB Cluster binary (GPL) 8.0.15-31.33, Revision -debug - UNIV_DEBUG ON)
        2019-03-25T08:31:18.676631Z WSREP_SST: [DEBUG] Found the mysqladmin binary in /dev/shm/qa/pxc80/bin/mysqladmin
        2019-03-25T08:31:18.680552Z WSREP_SST: [DEBUG] -- Ver 8.0.15-5-31.33 for Linux on x86_64 (Percona XtraDB Cluster binary (GPL) 8.0.15-31.33, Revision -debug - UNIV_DEBUG ON)
        2019-03-25T08:31:18.681274Z WSREP_SST: [DEBUG] Found the mysql binary in /dev/shm/qa/pxc80/bin/mysql
        2019-03-25T08:31:18.684050Z WSREP_SST: [DEBUG] -- Ver 8.0.15-5-31.33 for Linux on x86_64 (Percona XtraDB Cluster binary (GPL) 8.0.15-31.33, Revision -debug - UNIV_DEBUG ON)
        2019-03-25T08:31:18.716131Z WSREP_SST: [DEBUG] Starting the MySQL server(#1) used for post-processing
        2019-03-25T08:31:18.717035Z WSREP_SST: [DEBUG] MySQL server(10965) started
        2019-03-25T08:31:34.826709Z WSREP_SST: [DEBUG] MySQL server shut down
        2019-03-25T08:31:34.827472Z WSREP_SST: [DEBUG] Starting the MySQL server(#2) used for post-processing
        2019-03-25T08:31:34.839842Z WSREP_SST: [INFO] Waiting for server instance to start.....  This may take some time
        2019-03-25T08:31:36.860388Z WSREP_SST: [DEBUG] MySQL server(11012) started
        2019-03-25T08:31:36.861134Z WSREP_SST: [INFO] Running mysql_upgrade  donor:0.0.0  local:8.0.15
        2019-03-25T08:31:36.861851Z WSREP_SST: [DEBUG] Starting mysql_upgrade
        2019-03-25T08:31:53.501344Z WSREP_SST: [DEBUG] mysql_upgrade completed
        2019-03-25T08:31:53.502120Z WSREP_SST: [DEBUG] Creating wsrep state file:/dev/shm/qa/node3//wsrep_state.dat (version:1.0 wsrep:8.0.15)
        2019-03-25T08:31:53.502890Z WSREP_SST: [DEBUG] Shutting down the MySQL server
        2019-03-25T08:31:55.548710Z WSREP_SST: [DEBUG] MySQL server shut down
        2019-03-25T08:31:55.550396Z WSREP_SST: [INFO] ...........post-processing done
        2019-03-25T08:31:55.552925Z WSREP_SST: [DEBUG] Joiner cleanup. rsync PID: 0
        2019-03-25T08:31:55.557414Z WSREP_SST: [DEBUG] Joiner cleanup done.
2019-03-25T08:31:16.030983Z 0 [Warning] [MY-010097] [Server] Insecure configuration for --secure-file-priv: Current value does not restrict location of generated files. Consider setting it to a valid, non-empty path.