bpo-42972: Fix sqlite3 traverse/clear functions (GH-26452) (GH-26461)

(cherry picked from commit d1124b09e8251061dc040cbd396f35ae57783f4a)

Co-authored-by: Erlend Egeberg Aasland <erlend.aasland@innova.no>

1 files changed, 15 insertions, 14 deletions

diff --git a/Modules/_sqlite/cursor.c b/Modules/_sqlite/cursor.c
index acd3ea2..558b43a 100644
--- a/Modules/_sqlite/cursor.c
+++ b/Modules/_sqlite/cursor.c
@@ -84,43 +84,44 @@ pysqlite_cursor_init_impl(pysqlite_Cursor *self,
 static int
 cursor_traverse(pysqlite_Cursor *self, visitproc visit, void *arg)
 {
+    Py_VISIT(Py_TYPE(self));
     Py_VISIT(self->connection);
+    Py_VISIT(self->description);
     Py_VISIT(self->row_cast_map);
+    Py_VISIT(self->lastrowid);
     Py_VISIT(self->row_factory);
+    Py_VISIT(self->statement);
     Py_VISIT(self->next_row);
-    Py_VISIT(Py_TYPE(self));
     return 0;
 }
 
 static int
 cursor_clear(pysqlite_Cursor *self)
 {
-    /* Reset the statement if the user has not closed the cursor */
-    if (self->statement) {
-        pysqlite_statement_reset(self->statement);
-        Py_CLEAR(self->statement);
-    }
-
     Py_CLEAR(self->connection);
-    Py_CLEAR(self->row_cast_map);
     Py_CLEAR(self->description);
+    Py_CLEAR(self->row_cast_map);
     Py_CLEAR(self->lastrowid);
     Py_CLEAR(self->row_factory);
-    Py_CLEAR(self->next_row);
-
-    if (self->in_weakreflist != NULL) {
-        PyObject_ClearWeakRefs((PyObject*)self);
+    if (self->statement) {
+        /* Reset the statement if the user has not closed the cursor */
+        pysqlite_statement_reset(self->statement);
+        Py_CLEAR(self->statement);
     }
+    Py_CLEAR(self->next_row);
 
     return 0;
 }
 
 static void
-cursor_dealloc(PyObject *self)
+cursor_dealloc(pysqlite_Cursor *self)
 {
     PyTypeObject *tp = Py_TYPE(self);
     PyObject_GC_UnTrack(self);
-    tp->tp_clear(self);
+    if (self->in_weakreflist != NULL) {
+        PyObject_ClearWeakRefs((PyObject*)self);
+    }
+    tp->tp_clear((PyObject *)self);
     tp->tp_free(self);
     Py_DECREF(tp);
 }