diff --git a/Python/errors.c b/Python/errors.c index c88a1909c7f..02e9572173a 100644 --- a/Python/errors.c +++ b/Python/errors.c @@ -106,10 +106,16 @@ PyErr_GivenExceptionMatches(PyObject *err, PyObject *exc) err = PyExceptionInstance_Class(err); if (PyExceptionClass_Check(err) && PyExceptionClass_Check(exc)) { - int res = 0; + int res = 0, reclimit; PyObject *exception, *value, *tb; PyErr_Fetch(&exception, &value, &tb); + /* Temporarily bump the recursion limit, so that in the most + common case PyObject_IsSubclass will not raise a recursion + error we have to ignore anyway. */ + reclimit = Py_GetRecursionLimit(); + Py_SetRecursionLimit(reclimit + 5); res = PyObject_IsSubclass(err, exc); + Py_SetRecursionLimit(reclimit); /* This function must not fail, so print the error here */ if (res == -1) { PyErr_WriteUnraisable(err);