Parse #![variants_from_header] inner attribute
diff --git a/syntax/mod.rs b/syntax/mod.rs
index 96aa4c9..1eae19e 100644
--- a/syntax/mod.rs
+++ b/syntax/mod.rs
@@ -111,6 +111,7 @@
     pub generics: Lifetimes,
     pub brace_token: Brace,
     pub variants: Vec<Variant>,
+    pub variants_from_header: bool,
     pub repr: Atom,
     pub repr_type: Type,
     pub explicit_repr: bool,