diff --git a/Modules/_pickle.c b/Modules/_pickle.c
index a750351..bcbd3c0 100644
--- a/Modules/_pickle.c
+++ b/Modules/_pickle.c
@@ -7965,6 +7965,7 @@
     Py_VISIT(st->import_mapping_3to2);
     Py_VISIT(st->codecs_encode);
     Py_VISIT(st->getattr);
+    Py_VISIT(st->partial);
     return 0;
 }