public static void unlinkFixedNode(FixedWithNextNode fixed) {
assert fixed.next() != null && fixed.predecessor() != null && fixed.isAlive();
FixedNode next = fixed.next();
fixed.setNext(null);
fixed.replaceAtPredecessor(next);
}
private void setLastFixedNode(FixedWithNextNode n) {
assert n.isAlive() : n;
lastFixedNode = n;
}