--- jsr166/src/test/tck/JSR166TestCase.java	2019/09/29 20:18:35	1.270
+++ jsr166/src/test/tck/JSR166TestCase.java	2020/02/01 18:52:17	1.271
@@ -1200,8 +1200,9 @@ public class JSR166TestCase extends Test
         } catch (TimeoutException success) {
         } catch (Exception fail) {
             threadUnexpectedException(fail);
-        } finally { future.cancel(true); }
+        }
         assertTrue(millisElapsedSince(startTime) >= timeoutMillis);
+        assertFalse(future.isDone());
     }
 
     /**