--- jsr166/src/jsr166y/ForkJoinTask.java	2013/01/09 02:51:37	1.99
+++ jsr166/src/jsr166y/ForkJoinTask.java	2015/09/03 22:54:46	1.102
@@ -395,11 +395,13 @@ public abstract class ForkJoinTask<V> im
         final Throwable ex;
         ExceptionNode next;
         final long thrower;  // use id not ref to avoid weak cycles
+        final int hashCode;  // store task hashCode before weak ref disappears
         ExceptionNode(ForkJoinTask<?> task, Throwable ex, ExceptionNode next) {
             super(task, exceptionTableRefQueue);
             this.ex = ex;
             this.next = next;
             this.thrower = Thread.currentThread().getId();
+            this.hashCode = System.identityHashCode(task);
         }
     }
 
@@ -468,7 +470,7 @@ public abstract class ForkJoinTask<V> im
     }
 
     /**
-     * Removes exception node and clears status
+     * Removes exception node and clears status.
      */
     private void clearExceptionalCompletion() {
         int h = System.identityHashCode(this);
@@ -561,9 +563,9 @@ public abstract class ForkJoinTask<V> im
     private static void expungeStaleExceptions() {
         for (Object x; (x = exceptionTableRefQueue.poll()) != null;) {
             if (x instanceof ExceptionNode) {
-                ForkJoinTask<?> key = ((ExceptionNode)x).get();
+                int hashCode = ((ExceptionNode)x).hashCode;
                 ExceptionNode[] t = exceptionTable;
-                int i = System.identityHashCode(key) & (t.length - 1);
+                int i = hashCode & (t.length - 1);
                 ExceptionNode e = t[i];
                 ExceptionNode pred = null;
                 while (e != null) {
@@ -1326,7 +1328,7 @@ public abstract class ForkJoinTask<V> im
     }
 
     /**
-     * Adaptor for Runnables. This implements RunnableFuture
+     * Adapter for Runnables. This implements RunnableFuture
      * to be compliant with AbstractExecutorService constraints
      * when used in ForkJoinPool.
      */
@@ -1347,7 +1349,7 @@ public abstract class ForkJoinTask<V> im
     }
 
     /**
-     * Adaptor for Runnables without results
+     * Adapter for Runnables without results
      */
     static final class AdaptedRunnableAction extends ForkJoinTask<Void>
         implements RunnableFuture<Void> {
@@ -1364,7 +1366,7 @@ public abstract class ForkJoinTask<V> im
     }
 
     /**
-     * Adaptor for Callables
+     * Adapter for Callables
      */
     static final class AdaptedCallable<T> extends ForkJoinTask<T>
         implements RunnableFuture<T> {