src/hotspot/share/oops/klass.cpp

@@ -807,14 +807,14 @@
     if (module->is_named()) {
       has_mod_name = true;
       module_name = module->name()->as_C_string();
       msglen += strlen(module_name);
       // Use version if exists and is not a jdk module
-      if (module->is_non_jdk_module() && module->version() != NULL) {
+      if (module->should_show_version()) {
         has_version = true;
         version = module->version()->as_C_string();
-        msglen += strlen("@") + strlen(version);
+        msglen += strlen(version) + 1; // +1 for "@"
       }
     }
   } else {
     // klass is an array of primitives, so its module is java.base
     module_name = JAVA_BASE_NAME;