{"ast_node_type":"other","tokens":[{"end":114,"kind":"keyword","start":0,"text":"//"}]}
        // FIXME(explicit_tail_calls): should we have the span for `become`? is this span accurate? do we need it?
        args: Box<[Spanned<Operand<'tcx>>]>,
        /// This `Span` is the span of the function, without the dot and receiver