1 files changed, 6 insertions, 0 deletions
diff --git a/Python/gc_free_threading.c b/Python/gc_free_threading.c
index 70dace9..4c459b0 100644
--- a/Python/gc_free_threading.c
+++ b/Python/gc_free_threading.c
@@ -433,6 +433,12 @@ static void
 gc_visit_thread_stacks(PyInterpreterState *interp, struct collection_state *state)
 {
     _Py_FOR_EACH_TSTATE_BEGIN(interp, p) {
+        _PyCStackRef *c_ref = ((_PyThreadStateImpl *)p)->c_stack_refs;
+        while (c_ref != NULL) {
+            gc_visit_stackref(c_ref->ref);
+            c_ref = c_ref->next;
+        }
+
         for (_PyInterpreterFrame *f = p->current_frame; f != NULL; f = f->previous) {
             if (f->owner >= FRAME_OWNED_BY_INTERPRETER) {
                 continue;