I'm surprised more people are not calling out "enqueue() happily overwrites current_tail->next even if it is not null (which may happen if some other producer

I'm surprised more people are not calling out "enqueue() happily overwrites current_tail->next even if it is not null (which may happen if some other producer has enqueued something since we read current_tail)." Its probably one of the bigger problems of this queue, basically negates the whole structure with this bug.