gboolean is_parallel;
GCObject* (*alloc_for_promotion) (GCVTable vtable, GCObject *obj, size_t objsize, gboolean has_references);
+ GCObject* (*alloc_for_promotion_par) (GCVTable vtable, GCObject *obj, size_t objsize, gboolean has_references);
SgenObjectOperations serial_ops;
SgenObjectOperations serial_ops_with_concurrent_major;