diff --git a/Objects/classobject.c b/Objects/classobject.c
index 9375e07..0df249d 100644
--- a/Objects/classobject.c
+++ b/Objects/classobject.c
@@ -953,6 +953,7 @@
 				return _Py_HashPointer(inst);
 			}
 		}
+		Py_XDECREF(func);
 		PyErr_SetString(PyExc_TypeError, "unhashable instance");
 		return -1;
 	}