--- jsr166/src/test/tck/JSR166TestCase.java	2019/08/22 22:27:57	1.259
+++ jsr166/src/test/tck/JSR166TestCase.java	2019/09/05 17:27:07	1.260
@@ -754,8 +754,8 @@ public class JSR166TestCase extends Test
      */
     public void threadRecordFailure(Throwable t) {
         System.err.println(t);
-        dumpTestThreads();
-        threadFailure.compareAndSet(null, t);
+        if (threadFailure.compareAndSet(null, t))
+            dumpTestThreads();
     }
 
     public void setUp() {