How to demonstrate java multithreading visibility problems?

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By modifying the example here by removing operations I have come up with an example that consistently fails in my environment (the thread never stops running).

// Java environment:
// java version "1.6.0_0"
// OpenJDK Runtime Environment (IcedTea6 1.6.1) (6b16-1.6.1-3ubuntu3)
// OpenJDK 64-Bit Server VM (build 14.0-b16, mixed mode)
public class Test2 extends Thread {
    boolean keepRunning = true;
    public static void main(String[] args) throws InterruptedException {
        Test2 t = new Test2();
        t.start();
        Thread.sleep(1000);
        t.keepRunning = false;
        System.out.println(System.currentTimeMillis() + ": keepRunning is false");
    }
    public void run() {
        while (keepRunning) 
        {}
    }
}

Note that this type of problems are quite dependent on the compiler/runtime/system. In particular the compiler can determine to add instructions to read the variable from memory even if it is not volatile –so the code would work–, the vm and jit can optimize away the reads from memory and use only registers, and even the processor can reorder instructions –that would not affect this case, but in other multithreaded cases it can affect the perceived state from other threads if more than one variable are modified.

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