在弹出方法堆栈框架后，Throwable对象中的原因字段被设置为此

Question

这是我的openj9版本：

openjdk version "11.0.10" 2021-01-19
OpenJDK Runtime Environment AdoptOpenJDK (build 11.0.10+9)
Eclipse OpenJ9 VM AdoptOpenJDK (build openj9-0.24.0, JRE 11 Linux amd64-64-Bit Compressed References 20210120_910 (JIT enabled, AOT enabled)
OpenJ9   - 345e1b09e
OMR      - 741e94ea8
JCL      - 0a86953833 based on jdk-11.0.10+9)

当我在像HotSpot这样的其他JVM中运行以下程序时：

package dacapo6_26;

class Option {
    public boolean isRequired() {
        try {
            OutOfMemoryError var6 = new OutOfMemoryError("java.lang.OutOfMemoryError in ThrowCatch without counter");
            var6.initCause(new OutOfMemoryError("java.lang.OutOfMemoryError as cause exception"));
            throw var6;
        } catch (OutOfMemoryError var3) {
            /*
                The calling of var3.initCause would throw an IllegalStateException,
                since var6 has EXPLICITLY set a cause exception at line 7.
             */
            var3.initCause(new NoSuchMethodException("Cause Exception"));
        }
        return true;
    }
}

public class Harness {
    public static void main(String[] args) {
        try {
            Option option = new Option();
            System.out.println(option.isRequired());
        } catch (Exception var11) {
            /*
                The calling of var11.initCause would throw an IllegalStateException,
                since var11 has IMPLICITLY set a cause exception at line 14.
             */
            var11.initCause(new NoSuchMethodException("Cause Exception"));
            System.err.println("should not reach here");
        }
    }
}

结果是：

Exception in thread "main" java.lang.IllegalStateException: Can't overwrite cause with java.lang.NoSuchMethodException: Cause Exception
    at java.base/java.lang.Throwable.initCause(Throwable.java:462)
    at dacapo6_26.Harness.main(Harness.java:33)
Caused by: java.lang.IllegalStateException: Can't overwrite cause with java.lang.NoSuchMethodException: Cause Exception
    at java.base/java.lang.Throwable.initCause(Throwable.java:462)
    at dacapo6_26.Option.isRequired(Harness.java:12)
    at dacapo6_26.Harness.main(Harness.java:29)
Caused by: java.lang.OutOfMemoryError: java.lang.OutOfMemoryError in ThrowCatch without counter
    at dacapo6_26.Option.isRequired(Harness.java:6)
    ... 1 more
Caused by: java.lang.OutOfMemoryError: java.lang.OutOfMemoryError as cause exception
    at dacapo6_26.Option.isRequired(Harness.java:7)
    ... 1 more

但是在OpenJ9上运行时，结果是：

should not reach here

结果是预期的，还是OpenJ9中的一个bug？

OpenJ9是否遗漏了在var3.initCause(new NoSuchMethodException("Cause Exception"));行获得的cause字段信息？

谢谢!

Answer 1

此差异已得到纠正；请参见https://github.com/eclipse-openj9/openj9/pull/14877。修复应该在下一个(0.33.0)版本的OpenJ9中。