src/java.base/share/classes/java/util/concurrent/locks/AbstractQueuedLongSynchronizer.java

*** 63,72 ****
--- 63,77 ----
      extends AbstractOwnableSynchronizer
      implements java.io.Serializable {
  
      private static final long serialVersionUID = 7373984972572414692L;
  
+     /**
+      * Constructor for subclasses to call.
+      */
+     public AbstractQueuedLongSynchronizer() {}
+ 
      /*
       * To keep sources in sync, the remainder of this source file is
       * exactly cloned from AbstractQueuedSynchronizer, replacing class
       * name and changing ints related with sync state to longs. Please
       * keep it that way.