MARK_CHECKPOINT  4694 gc.c               MARK_CHECKPOINT("vm");
MARK_CHECKPOINT  4699 gc.c               MARK_CHECKPOINT("finalizers");
MARK_CHECKPOINT  4702 gc.c               MARK_CHECKPOINT("machine_context");
MARK_CHECKPOINT  4705 gc.c               MARK_CHECKPOINT("encodings");
MARK_CHECKPOINT  4709 gc.c               MARK_CHECKPOINT("global_list");
MARK_CHECKPOINT  4714 gc.c               MARK_CHECKPOINT("end_proc");
MARK_CHECKPOINT  4717 gc.c               MARK_CHECKPOINT("global_tbl");
MARK_CHECKPOINT  4722 gc.c               MARK_CHECKPOINT("finish");