#define xbt_swag_getNext(obj, offset) (((xbt_swag_hookup_t)(((char *) (obj)) + (offset)))->next)
#define xbt_swag_belongs(obj, swag) (xbt_swag_getNext((obj), (swag)->offset) || (swag)->tail == (obj))
#define xbt_swag_getNext(obj, offset) (((xbt_swag_hookup_t)(((char *) (obj)) + (offset)))->next)
#define xbt_swag_belongs(obj, swag) (xbt_swag_getNext((obj), (swag)->offset) || (swag)->tail == (obj))