Issue #13070: Fix a crash when a TextIOWrapper caught in a reference cycle
would be finalized after the reference to its underlying BufferedRWPair's
writer got cleared by the GC.
diff --git a/Modules/_io/bufferedio.c b/Modules/_io/bufferedio.c
index 73f924e..1b81647 100644
--- a/Modules/_io/bufferedio.c
+++ b/Modules/_io/bufferedio.c
@@ -2179,6 +2179,11 @@
static PyObject *
bufferedrwpair_closed_get(rwpair *self, void *context)
{
+ if (self->writer == NULL) {
+ PyErr_SetString(PyExc_RuntimeError,
+ "the BufferedRWPair object is being garbage-collected");
+ return NULL;
+ }
return PyObject_GetAttr((PyObject *) self->writer, _PyIO_str_closed);
}