src/java.base/share/classes/java/lang/reflect/Field.java

*** 165,174 ****
--- 165,180 ----
       */
      @Override
      @CallerSensitive
      public void setAccessible(boolean flag) {
          AccessibleObject.checkPermission();
+ 
+         if (clazz.isValue() && Modifier.isFinal(modifiers)) {
+             throw new InaccessibleObjectException(
+                 "Unable to make a value class field \"" + this + "\" accessible");
+         }
+ 
          if (flag) checkCanSetAccessible(Reflection.getCallerClass());
          setAccessible0(flag);
      }
  
      @Override