Change _PyObject_GC_Resize to expect Py_ssize_t.
diff --git a/Modules/gcmodule.c b/Modules/gcmodule.c
index 4902eb5..42dfa15 100644
--- a/Modules/gcmodule.c
+++ b/Modules/gcmodule.c
@@ -1284,7 +1284,7 @@
 }
 
 PyVarObject *
-_PyObject_GC_Resize(PyVarObject *op, int nitems)
+_PyObject_GC_Resize(PyVarObject *op, Py_ssize_t nitems)
 {
 	const size_t basicsize = _PyObject_VAR_SIZE(op->ob_type, nitems);
 	PyGC_Head *g = AS_GC(op);