TAILQ_FIRST
next_scb = TAILQ_FIRST(untagged_q);
if (TAILQ_FIRST(untagged_q) == NULL)
if ((scb = TAILQ_FIRST(queue)) != NULL
for (cs = TAILQ_FIRST(&cs_tailq);
cs == TAILQ_FIRST(&cs_tailq) ? "" : ",\n",
cur_scope = TAILQ_FIRST(&scope->inner_scope);
for ((var) = TAILQ_FIRST((head)); \
TAILQ_FIRST((head)) = NULL; \
(head)->tqh_last = &TAILQ_FIRST((head)); \
if ((TAILQ_NEXT((elm), field) = TAILQ_FIRST((head))) != NULL) \
TAILQ_FIRST((head))->field.tqe_prev = \
TAILQ_FIRST((head)) = (elm); \
(elm)->field.tqe_prev = &TAILQ_FIRST((head)); \