From c7fba524cb023be57f4f34c50f116197d198ec0a Mon Sep 17 00:00:00 2001 From: Paul Sokolovsky Date: Sun, 19 Jun 2016 00:56:06 +0300 Subject: [PATCH] py/objtype: Inherit protocol vtable from base class only if it exists. --- py/objtype.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/py/objtype.c b/py/objtype.c index 3020ed513d..907308a757 100644 --- a/py/objtype.c +++ b/py/objtype.c @@ -918,7 +918,9 @@ mp_obj_t mp_obj_new_type(qstr name, mp_obj_t bases_tuple, mp_obj_t locals_dict) // abstract base class which would translate C-level protocol to // Python method calls, and any subclass inheriting from it will // support this feature. - o->protocol = ((mp_obj_type_t*)MP_OBJ_TO_PTR(items[0]))->protocol; + if (len > 0) { + o->protocol = ((mp_obj_type_t*)MP_OBJ_TO_PTR(items[0]))->protocol; + } o->bases_tuple = MP_OBJ_TO_PTR(bases_tuple); o->locals_dict = MP_OBJ_TO_PTR(locals_dict);