SafepointBug.java

import org.jctools.queues.MpscUnboundedArrayQueue;

import java.util.concurrent.TimeUnit;
import java.util.concurrent.locks.LockSupport;

public class Main {

    public static final long HEALTH_INT = TimeUnit.SECONDS.toNanos(1);


    public static volatile long l;
    public static void main(String[] args) {

        MpscUnboundedArrayQueue<Long> queue = new MpscUnboundedArrayQueue<Long>(1024);


        Thread thealth = new Thread(() -> {
            do {
                LockSupport.parkNanos(HEALTH_INT);
                System.out.println(" healthy " + l);
            } while (true);
        }, "thealth");




        Thread tOffer = new Thread(() -> {
            long l = 0;
            do {
                queue.offer(l++);
                LockSupport.parkNanos(1);
            } while(true);
        }, "toffer");


        Thread tConsumer = new Thread(() -> {
            do {
                Long ll = queue.poll();
                if (ll != null)
                    Main.l = ll;
                LockSupport.parkNanos(1);
            } while(true);
        }, "tpoll");


        thealth.start();

        tConsumer.start();
        tOffer.start();
    }
}