LEFT_ENTRY
cur = LEFT_ENTRY(cur);
else if ((child = LEFT_ENTRY(tmp)) != NULL
child = LEFT_ENTRY(tmp);
child = LEFT_ENTRY(tmp);
tmp = LEFT_ENTRY(prev);
child = LEFT_ENTRY(tmp);
tmp = LEFT_ENTRY(tmp);
if ((child = LEFT_ENTRY(entry)) != NULL && maxgap < child->maxgap)
LEFT_ENTRY(entry) == entry->prev ? entry->prev : entry);