for (idx = count / 2; idx >= 1; idx--)
heapify (array, count, size, idx, compare, aux);
expensive_assert (count < 1 || is_heap (array, count, size, compare, aux));
for (idx = count / 2; idx >= 1; idx--)
heapify (array, count, size, idx, compare, aux);
expensive_assert (count < 1 || is_heap (array, count, size, compare, aux));