{"ast_node_type":"other","tokens":[{"end":61,"kind":"keyword","start":0,"text":"///"}]}
    /// require the `-Zunstable-options` flag, to be allowed.
    /// unstable components was set individually, for the given `TargetTuple`. This would also
    fn check_unstable_variants(&self, target_tuple: &TargetTuple) -> Result<(), String> {