instruction-reordering

来源： https://stackoverflow.com/questions/58804138/memory-model-how-load-acquire-semantic-actually-works

问题 Below code sample is taken from JLS 17.5 "final Field Semantics": class FinalFieldExample { final int x; int y; static FinalFieldExample f; public FinalFieldExample() { x = 3; y = 4; } static void writer() { f = new FinalFieldExample(); } static void reader() { if (f != null) { int i = f.x; // guaranteed to see 3 int j = f.y; // could see 0 } } } Since the instance of FinalFieldExample is published through a data race, is it possible that the f != null check evaluates successfully, yet

问题 With Java instruction reordering the execution order of the code is changed by the JVM at compile time or run time, possibly causing unrelated statements to be executed out-of-order. So my question is: Can someone provide an example Java program/snippet, that reliably shows an instruction reordering problem, that is not caused also by other synchronization issues ( such as caching/visibility or non-atomic r/w, as in my failed attempt at such a demo in my previous question ) To emphasize, I am

问题 With Java instruction reordering the execution order of the code is changed by the JVM at compile time or run time, possibly causing unrelated statements to be executed out-of-order. So my question is: Can someone provide an example Java program/snippet, that reliably shows an instruction reordering problem, that is not caused also by other synchronization issues ( such as caching/visibility or non-atomic r/w, as in my failed attempt at such a demo in my previous question ) To emphasize, I am