src/java.xml.bind/share/classes/javax/xml/bind/ModuleUtil.java

@@ -128,13 +128,10 @@
      *
      * @throws JAXBException if ony of a classes package is not open to {@code java.xml.bind} module.
      */
     static void delegateAddOpensToImplModule(Class[] classes, Class<?> factorySPI) throws JAXBException {
         final Module implModule = factorySPI.getModule();
-        if (!implModule.isNamed()) {
-            return;
-        }
 
         Module jaxbModule = JAXBContext.class.getModule();
 
         for (Class cls : classes) {
             final Module classModule = cls.getModule();