src/java.base/share/classes/jdk/internal/loader/BootLoader.java

@@ -222,11 +222,11 @@
 
             if (moduleName != null) {
                 // named module from runtime image or exploded module
                 Optional<Module> om = BOOT_LAYER.findModule(moduleName);
                 if (!om.isPresent())
-                    throw new InternalError();
+                    throw new InternalError("Module not present:" + moduleName);
                 return om.get();
             }
 
             return null;
         }