I noticed today that the defsystem grammar info node does not include the :class option. The attached patch fixes that.
diff --git a/asdf.texinfo b/asdf.texinfo index cfef5c6..b539182 100644 --- a/asdf.texinfo +++ b/asdf.texinfo @@ -339,7 +339,8 @@ option := :components component-list | :operation-done-p method-form | :depends-on ( {dependency-def}* ) | :serial [ t | nil ] - | :in-order-to ( {dependency}+ ) + | :in-order-to ( {dependency}+ ) + | :class symbol
component-list := ( {component-def}* )