1 files changed, 14 insertions, 6 deletions
diff --git a/Objects/abstract.c b/Objects/abstract.c
index 6f7b946..6227ad5 100644
--- a/Objects/abstract.c
+++ b/Objects/abstract.c
@@ -2557,14 +2557,22 @@ abstract_issubclass(PyObject *derived, PyObject *cls)
             derived = PyTuple_GET_ITEM(bases, 0);
             continue;
         }
-        for (i = 0; i < n; i++) {
-            r = abstract_issubclass(PyTuple_GET_ITEM(bases, i), cls);
-            if (r != 0)
-                break;
-        }
+        break;
+    }
+    assert(n >= 2);
+    if (Py_EnterRecursiveCall(" in __issubclass__")) {
         Py_DECREF(bases);
-        return r;
+        return -1;
     }
+    for (i = 0; i < n; i++) {
+        r = abstract_issubclass(PyTuple_GET_ITEM(bases, i), cls);
+        if (r != 0) {
+            break;
+        }
+    }
+    Py_LeaveRecursiveCall();
+    Py_DECREF(bases);
+    return r;
 }
 
 static int