diff --git a/core/my_basic.c b/core/my_basic.c
index bc9eaf5..10b5490 100755
--- a/core/my_basic.c
+++ b/core/my_basic.c
@@ -6405,9 +6405,11 @@ static int _gc_add_reachable(void* data, void* extra, void* h) {
 	case _DT_ROUTINE:
 		if(obj->data.routine->type == MB_RT_LAMBDA) {
 			if(!_ht_find(ht, &obj->data.routine->func.lambda.ref)) {
+				_running_context_ref_t* outs = obj->data.routine->func.lambda.outer_scope;
 				_ht_set_or_insert(ht, &obj->data.routine->func.lambda.ref, obj->data.routine);
-				if(obj->data.routine->func.lambda.outer_scope) {
-					_HT_FOREACH(obj->data.routine->func.lambda.outer_scope->scope->var_dict, _do_nothing_on_object, _gc_add_reachable, ht);
+				while(outs) {
+					_HT_FOREACH(outs->scope->var_dict, _do_nothing_on_object, _gc_add_reachable, ht);
+					outs = outs->prev;
 				}
 			}
 		}