Return an error code from _PyCrossInterpreterData_Release().

python · ericsnowcurrently · Dec 2, 2022 · Nov 21, 2022 · Nov 21, 2022 · Nov 21, 2022
commit 4f9baf0a4d56c1e166c31e01147e1ce595580b13
@@ -394,7 +394,7 @@ struct _xid {
 
 PyAPI_FUNC(int) _PyObject_GetCrossInterpreterData(PyObject *, _PyCrossInterpreterData *);
 PyAPI_FUNC(PyObject *) _PyCrossInterpreterData_NewObject(_PyCrossInterpreterData *);
-PyAPI_FUNC(void) _PyCrossInterpreterData_Release(_PyCrossInterpreterData *);
+PyAPI_FUNC(int) _PyCrossInterpreterData_Release(_PyCrossInterpreterData *);
 
 PyAPI_FUNC(int) _PyObject_CheckCrossInterpreterData(PyObject *);
 

diff --git a/Lib/test/test__xxsubinterpreters.py b/Lib/test/test__xxsubinterpreters.py
@@ -1545,6 +1545,19 @@ def test_recv_default(self):
         self.assertEqual(obj5, b'eggs')
         self.assertIs(obj6, default)
 
+    def test_recv_sending_interp_destroyed(self):
+        cid = interpreters.channel_create()
+        interp = interpreters.create()
+        interpreters.run_string(interp, dedent(f"""
+            import _xxsubinterpreters as _interpreters
+            _interpreters.channel_send({cid}, b'spam')
+            """))
+        interpreters.destroy(interp)
+
+        with self.assertRaisesRegex(RuntimeError,
+                                    'unrecognized interpreter ID'):
+            interpreters.channel_recv(cid)
+
     def test_run_string_arg_unresolved(self):
         cid = interpreters.channel_create()
         interp = interpreters.create()

diff --git a/Modules/_xxsubinterpretersmodule.c b/Modules/_xxsubinterpretersmodule.c
@@ -103,9 +103,8 @@ _release_xid_data(_PyCrossInterpreterData *data, int ignoreexc)
     if (ignoreexc) {
         PyErr_Fetch(&exctype, &excval, &exctb);
     }
-    int res = 0;
-    _PyCrossInterpreterData_Release(data);
-    if (PyErr_Occurred()) {
+    int res = _PyCrossInterpreterData_Release(data);
+    if (res < 0) {
         // XXX Fix this!
         /* The owning interpreter is already destroyed.
          * Ideally, this shouldn't ever happen.  When an interpreter is
@@ -128,7 +127,6 @@ _release_xid_data(_PyCrossInterpreterData *data, int ignoreexc)
             // XXX Emit a warning?
             PyErr_Clear();
         }
-        res = 1;
     }
     if (ignoreexc) {
         PyErr_Restore(exctype, excval, exctb);
@@ -1512,6 +1510,7 @@ _channel_recv(_channels *channels, int64_t id, PyObject **res)
         return err;
     }
     else if (data == NULL) {
+        assert(!PyErr_Occurred());
         return 0;
     }
 

@@ -1865,7 +1865,7 @@ _PyObject_GetCrossInterpreterData(PyObject *obj, _PyCrossInterpreterData *data)
     // Fill in the blanks and validate the result.
     data->interp = interp->id;
     if (_check_xidata(tstate, data) != 0) {
-        _PyCrossInterpreterData_Release(data);
+        (void)_PyCrossInterpreterData_Release(data);
         return -1;
     }
 
@@ -1878,8 +1878,8 @@ _release_xidata(void *arg)
     _PyCrossInterpreterData *data = (_PyCrossInterpreterData *)arg;
     if (data->free != NULL) {
         data->free(data->data);
-        data->data = NULL;
     }
+    data->data = NULL;
     Py_CLEAR(data->obj);
 }
 
@@ -1910,27 +1910,29 @@ _call_in_interpreter(struct _gilstate_runtime_state *gilstate,
     }
 }
 
-void
+int
 _PyCrossInterpreterData_Release(_PyCrossInterpreterData *data)
 {
-    if (data->data == NULL && data->obj == NULL) {
+    if (data->free == NULL && data->obj == NULL) {
         // Nothing to release!
-        return;
+        data->data = NULL;
+        return 0;
     }
 
     // Switch to the original interpreter.
     PyInterpreterState *interp = _PyInterpreterState_LookUpID(data->interp);
     if (interp == NULL) {
         // The interpreter was already destroyed.
-        if (data->free != NULL) {
-            // XXX Someone leaked some memory...
-        }
-        return;
+        // This function shouldn't have been called.
+        // XXX Someone leaked some memory...
+        assert(PyErr_Occurred());
+        return -1;
     }
 
     // "Release" the data and/or the object.
     struct _gilstate_runtime_state *gilstate = &_PyRuntime.gilstate;
     _call_in_interpreter(gilstate, interp, _release_xidata, data);
+    return 0;
 }
 
 PyObject *