{"ast_node_type":"other","tokens":[{"end":76,"kind":"keyword","start":0,"text":"Extern::Explicit(StrLit"}]}
                Extern::Explicit(StrLit { symbol_unescaped: sym::C, .. }, _)
            (Some(FnCtxt::Free), Some(header)) => match header.ext {
                | Extern::Explicit(StrLit { symbol_unescaped: sym::C_dash_unwind, .. }, _)