diff --git a/contrib/pg_upgrade/test.sh b/contrib/pg_upgrade/test.sh
index 1ef80edbcbb32d457d5634b53675380276551b13..baa7d4748b6f521d5a99eb32885f2f9342abdb30 100644
--- a/contrib/pg_upgrade/test.sh
+++ b/contrib/pg_upgrade/test.sh
@@ -83,10 +83,10 @@ mkdir "$logdir"
 PGDATABASE="";        unset PGDATABASE
 PGUSER="";            unset PGUSER
 PGSERVICE="";         unset PGSERVICE
-PGSSLMODE=""          unset PGSSLMODE
+PGSSLMODE="";         unset PGSSLMODE
 PGREQUIRESSL="";      unset PGREQUIRESSL
 PGCONNECT_TIMEOUT=""; unset PGCONNECT_TIMEOUT
-PGHOST=""             unset PGHOST
+PGHOST="";            unset PGHOST
 PGHOSTADDR="";        unset PGHOSTADDR
 
 # Select a non-conflicting port number, similarly to pg_regress.c