--- old/src/hotspot/share/classfile/javaClasses.hpp	2019-01-10 15:10:50.965538021 +0100
+++ new/src/hotspot/share/classfile/javaClasses.hpp	2019-01-10 15:10:50.669537432 +0100
@@ -78,6 +78,8 @@
   f(reflect_UnsafeStaticFieldAccessorImpl) \
   f(java_lang_reflect_Parameter) \
   f(java_lang_Module) \
+  f(java_lang_module_ModuleDescriptor) \
+  f(java_lang_module_ModuleDescriptor_Version) \
   f(java_lang_StackTraceElement) \
   f(java_lang_StackFrameInfo) \
   f(java_lang_LiveStackFrameInfo) \
@@ -775,6 +777,7 @@
   private:
     static int loader_offset;
     static int name_offset;
+    static int module_descriptor_offset;
     static int _module_entry_offset;
     static void compute_offsets();
 
@@ -794,11 +797,47 @@
     static oop name(oop module);
     static void set_name(oop module, oop value);
 
+    static oop module_descriptor(oop module);
+
     static ModuleEntry* module_entry(oop module);
     static void set_module_entry(oop module, ModuleEntry* module_entry);
 
   friend class JavaClasses;
 };
+
+class java_lang_module_ModuleDescriptor {
+  private:
+    static int version_offset;
+    static void compute_offsets();
+
+  public:
+    static void serialize_offsets(SerializeClosure* f) NOT_CDS_RETURN;
+
+    // Testers
+    static bool is_instance(oop obj);
+
+    // Accessors
+    static oop version(oop module_descriptor);
+
+  friend class JavaClasses;
+};
+
+class java_lang_module_ModuleDescriptor_Version {
+  private:
+    static int version_offset;
+    static void compute_offsets();
+
+  public:
+    static void serialize_offsets(SerializeClosure* f) NOT_CDS_RETURN;
+
+    // Testers
+    static bool is_instance(oop obj);
+
+    // Accessors
+    static oop version(oop module_descriptor_version);
+
+  friend class JavaClasses;
+};
 
 // Interface to jdk.internal.reflect.ConstantPool objects
 class reflect_ConstantPool {