jdk/src/java.base/share/classes/java/lang/StackStreamFactory.java

@@ -69,10 +69,11 @@
     private static final int MIN_BATCH_SIZE    = SMALL_BATCH;
 
     // These flags must match the values maintained in the VM
     @Native private static final int DEFAULT_MODE              = 0x0;
     @Native private static final int FILL_CLASS_REFS_ONLY      = 0x2;
+    @Native private static final int GET_CALLER_CLASS          = 0x4;
     @Native private static final int SHOW_HIDDEN_FRAMES        = 0x20;  // LambdaForms are hidden by the VM
     @Native private static final int FILL_LIVE_STACK_FRAMES    = 0x100;
     /*
      * For Throwable to use StackWalker, set useNewThrowable to true.
      * Performance work and extensive testing is needed to replace the

@@ -612,13 +613,11 @@
         }
 
         private Class<?> caller;
 
         CallerClassFinder(StackWalker walker) {
-            super(walker, FILL_CLASS_REFS_ONLY);
-            assert (mode & FILL_CLASS_REFS_ONLY) == FILL_CLASS_REFS_ONLY
-                   : "mode should contain FILL_CLASS_REFS_ONLY";
+            super(walker, FILL_CLASS_REFS_ONLY|GET_CALLER_CLASS);
         }
 
         final class ClassBuffer extends FrameBuffer<Class<?>> {
             Class<?>[] classes;      // caller class for fast path
             ClassBuffer(int batchSize) {