1 files changed, 57 insertions, 9 deletions

diff --git a/Objects/exceptions.c b/Objects/exceptions.c
index 418bffb0a0..9258ace50a 100644
--- a/Objects/exceptions.c
+++ b/Objects/exceptions.c
@@ -250,11 +250,67 @@ BaseException_set_tb(PyBaseExceptionObject *self, PyObject *tb)
     return 0;
 }
 
+static PyObject *
+BaseException_get_context(PyObject *self) {
+    PyObject *res = PyException_GetContext(self);
+    if (res) return res;  /* new reference already returned above */
+    Py_RETURN_NONE;
+}
+
+static int
+BaseException_set_context(PyObject *self, PyObject *arg) {
+    if (arg == NULL) {
+        PyErr_SetString(PyExc_TypeError, "__context__ may not be deleted");
+        return -1;
+    } else if (arg == Py_None) {
+        arg = NULL;
+    } else if (!PyExceptionInstance_Check(arg)) {
+        PyErr_SetString(PyExc_TypeError, "exception context must be None "
+                        "or derive from BaseException");
+        return -1;
+    } else {
+        /* PyException_SetContext steals this reference */
+        Py_INCREF(arg);
+    } 
+    PyException_SetContext(self, arg);
+    return 0;
+}
+
+static PyObject *
+BaseException_get_cause(PyObject *self) {
+    PyObject *res = PyException_GetCause(self);
+    if (res) return res;  /* new reference already returned above */
+    Py_RETURN_NONE;
+}
+
+static int
+BaseException_set_cause(PyObject *self, PyObject *arg) {
+    if (arg == NULL) {
+        PyErr_SetString(PyExc_TypeError, "__cause__ may not be deleted");
+        return -1;
+    } else if (arg == Py_None) {
+        arg = NULL;
+    } else if (!PyExceptionInstance_Check(arg)) {
+        PyErr_SetString(PyExc_TypeError, "exception cause must be None "
+                        "or derive from BaseException");
+        return -1;
+    } else {
+        /* PyException_SetCause steals this reference */
+        Py_INCREF(arg);
+    } 
+    PyException_SetCause(self, arg);
+    return 0;
+}
+
 
 static PyGetSetDef BaseException_getset[] = {
     {"__dict__", (getter)BaseException_get_dict, (setter)BaseException_set_dict},
     {"args", (getter)BaseException_get_args, (setter)BaseException_set_args},
     {"__traceback__", (getter)BaseException_get_tb, (setter)BaseException_set_tb},
+    {"__context__", (getter)BaseException_get_context,
+     (setter)BaseException_set_context, PyDoc_STR("exception context")},
+    {"__cause__", (getter)BaseException_get_cause,
+     (setter)BaseException_set_cause, PyDoc_STR("exception cause")},
     {NULL},
 };
 
@@ -303,14 +359,6 @@ PyException_SetContext(PyObject *self, PyObject *context) {
 }
 
 
-static PyMemberDef BaseException_members[] = {
-    {"__context__", T_OBJECT, offsetof(PyBaseExceptionObject, context), 0,
-        PyDoc_STR("exception context")},
-    {"__cause__", T_OBJECT, offsetof(PyBaseExceptionObject, cause), 0,
-        PyDoc_STR("exception cause")},
-    {NULL}  /* Sentinel */
-};
-
 static PyTypeObject _PyExc_BaseException = {
     PyVarObject_HEAD_INIT(NULL, 0)
     "BaseException", /*tp_name*/
@@ -341,7 +389,7 @@ static PyTypeObject _PyExc_BaseException = {
     0,                          /* tp_iter */
     0,                          /* tp_iternext */
     BaseException_methods,      /* tp_methods */
-    BaseException_members,      /* tp_members */
+    0,                          /* tp_members */
     BaseException_getset,       /* tp_getset */
     0,                          /* tp_base */
     0,                          /* tp_dict */