# Clear out any environment vars that might cause libpq to connect to
# the wrong postmaster (cf pg_regress.c)
-unset PGDATABASE
-unset PGUSER
-unset PGSERVICE
-unset PGSSLMODE
-unset PGREQUIRESSL
-unset PGCONNECT_TIMEOUT
-unset PGHOST
-unset PGHOSTADDR
+#
+# Some shells, such as NetBSD's, return non-zero from unset if the variable
+# is already unset. Since we are operating under 'set -e', this causes the
+# script to fail. To guard against this, set them all to an empty string first.
+PGDATABASE=""; unset PGDATABASE
+PGUSER=""; unset PGUSER
+PGSERVICE=""; unset PGSERVICE
+PGSSLMODE="" unset PGSSLMODE
+PGREQUIRESSL=""; unset PGREQUIRESSL
+PGCONNECT_TIMEOUT=""; unset PGCONNECT_TIMEOUT
+PGHOST="" unset PGHOST
+PGHOSTADDR=""; unset PGHOSTADDR
# Select a non-conflicting port number, similarly to pg_regress.c
PG_VERSION_NUM=`grep '#define PG_VERSION_NUM' $newsrc/src/include/pg_config.h | awk '{print $3}'`