src/java.base/share/classes/java/io/ObjectStreamClass.java

@@ -1183,23 +1183,41 @@
             this.desc = desc;
             this.hasData = hasData;
         }
     }
 
+    private static final Unsafe U = Unsafe.getUnsafe();
+    private static final long   CDS_OFFSET;
+
+    static {
+        Field field = null;
+        try {
+            field = ObjectStreamClass.class.getDeclaredField("dataLayout");
+        } catch(NoSuchFieldException | SecurityException e) {
+        }
+        if(field == null) {
+            CDS_OFFSET = Unsafe.INVALID_FIELD_OFFSET;
+        } else {
+            CDS_OFFSET = U.objectFieldOffset(field);
+        }
+    }
+
     /**
      * Returns array of ClassDataSlot instances representing the data layout
      * (including superclass data) for serialized objects described by this
      * class descriptor.  ClassDataSlots are ordered by inheritance with those
      * containing "higher" superclasses appearing first.  The final
      * ClassDataSlot contains a reference to this descriptor.
      */
     ClassDataSlot[] getClassDataLayout() throws InvalidClassException {
         // REMIND: synchronize instead of relying on volatile?
-        if (dataLayout == null) {
-            dataLayout = getClassDataLayout0();
+        ClassDataSlot[] slots = (ClassDataSlot[])U.getObjectAcquire(this, CDS_OFFSET);
+        if (slots == null) {
+            slots = getClassDataLayout0();
+            U.putObjectRelease(this, CDS_OFFSET, slots);
         }
-        return dataLayout;
+        return slots;
     }
 
     private ClassDataSlot[] getClassDataLayout0()
         throws InvalidClassException
     {