Fix heap types in the stdlib to correctly visit its parent

Author: pablogsal

Modules/_abc.c

@@ -46,6 +46,10 @@ typedef struct {
 static int
 abc_data_traverse(_abc_data *self, visitproc visit, void *arg)
 {
+    PyTypeObject *parent = Py_TYPE(self);
+    if (parent->tp_traverse == (traverseproc)abc_data_traverse) {
+        Py_VISIT(parent);
+    }
     Py_VISIT(self->_abc_registry);
     Py_VISIT(self->_abc_cache);
     Py_VISIT(self->_abc_negative_cache);

Modules/_curses_panel.c

@@ -39,6 +39,10 @@ _curses_panel_clear(PyObject *m)
 static int
 _curses_panel_traverse(PyObject *m, visitproc visit, void *arg)
 {
+    PyTypeObject *parent = Py_TYPE(m);
+    if (parent->tp_traverse == (traverseproc)_curses_panel_traverse) {
+        Py_VISIT(parent);
+    }
     Py_VISIT(get_curses_panelstate(m)->PyCursesError);
     return 0;
 }

Modules/_json.c

@@ -1745,6 +1745,10 @@ encoder_dealloc(PyObject *self)
 static int
 encoder_traverse(PyEncoderObject *self, visitproc visit, void *arg)
 {
+    PyTypeObject *parent = Py_TYPE(self);
+    if (parent->tp_traverse == (traverseproc)encoder_traverse) {
+        Py_VISIT(parent);
+    }
     Py_VISIT(self->markers);
     Py_VISIT(self->defaultfn);
     Py_VISIT(self->encoder);

Modules/_struct.c

@@ -1641,6 +1641,10 @@ unpackiter_dealloc(unpackiterobject *self)
 static int
 unpackiter_traverse(unpackiterobject *self, visitproc visit, void *arg)
 {
+    PyTypeObject *parent = Py_TYPE(self);
+    if (parent->tp_traverse == (traverseproc)unpackiter_traverse) {
+        Py_VISIT(parent);
+    }
     Py_VISIT(self->so);
     Py_VISIT(self->buf.obj);
     return 0;

Objects/structseq.c

@@ -70,6 +70,11 @@ PyStructSequence_GetItem(PyObject* op, Py_ssize_t i)
 static int
 structseq_traverse(PyStructSequence *obj, visitproc visit, void *arg)
 {
+    PyTypeObject *parent = Py_TYPE(obj);
+    if (PyType_GetFlags(parent) & Py_TPFLAGS_HEAPTYPE &&
+        parent->tp_traverse == (traverseproc)structseq_traverse) {
+        Py_VISIT(parent);
+    }
     Py_ssize_t i, size;
     size = REAL_SIZE(obj);
     for (i = 0; i < size; ++i) {

Parser/asdl_c.py

@@ -673,6 +673,10 @@ def visitModule(self, mod):
 static int
 ast_traverse(AST_object *self, visitproc visit, void *arg)
 {
+    PyTypeObject *parent = Py_TYPE(self);
+    if (parent->tp_traverse == (traverseproc)ast_traverse) {
+        Py_VISIT(parent);
+    }
     Py_VISIT(self->dict);
     return 0;
 }