--- jsr166/src/test/tck/JSR166TestCase.java	2017/07/22 18:23:59	1.235
+++ jsr166/src/test/tck/JSR166TestCase.java	2017/08/23 05:33:00	1.237
@@ -544,6 +544,7 @@ public class JSR166TestCase extends Test
                 "DoubleAdderTest",
                 "ForkJoinPool8Test",
                 "ForkJoinTask8Test",
+                "HashMapTest",
                 "LinkedBlockingDeque8Test",
                 "LinkedBlockingQueue8Test",
                 "LongAccumulatorTest",
@@ -1913,6 +1914,18 @@ public class JSR166TestCase extends Test
         Collections.shuffle(Arrays.asList(array), ThreadLocalRandom.current());
     }
 
+    /**
+     * Returns the same String as would be returned by {@link
+     * Object#toString}, whether or not the given object's class
+     * overrides toString().
+     *
+     * @see System#identityHashCode
+     */
+    static String identityString(Object x) {
+        return x.getClass().getName()
+            + "@" + Integer.toHexString(System.identityHashCode(x));
+    }
+
     // --- Shared assertions for Executor tests ---
 
     /**