- if (arg)
- ((MonoArgumentException *)ex)->param_name =
- mono_string_new (mono_object_get_domain ((MonoObject*)ex), arg);
+ if (arg) {
+ MonoArgumentException *argex = (MonoArgumentException *)ex;
+ MONO_OBJECT_SETREF (argex, param_name, mono_string_new (mono_object_get_domain ((MonoObject*)ex), arg));
+ }