patch 7.4.1498
Problem:    Error for locked item when using json_decode(). (Shougo)
Solution:   Initialize v_lock.
diff --git a/src/json.c b/src/json.c
index b41d45e..34cf188 100644
--- a/src/json.c
+++ b/src/json.c
@@ -506,6 +506,7 @@
 		return FAIL;
 	    }
 	    di->di_tv = item;
+	    di->di_tv.v_lock = 0;
 	    if (dict_add(res->vval.v_dict, di) == FAIL)
 	    {
 		dictitem_free(di);