diff --git a/src/eval.c b/src/eval.c
index 31dff05..8afd52e 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -9886,6 +9886,7 @@
     int		todo;
     hashitem_T	*hi;
 
+    opt->jo_set = 0;
     if (tv->v_type == VAR_UNKNOWN)
 	return OK;
     if (tv->v_type != VAR_DICT)