{"ast_node_type":"other","tokens":[{"end":59,"kind":"keyword","start":0,"text":"//"}]}
            // For panic_fmt, call const_panic_fmt instead.
        } else if self.tcx.is_lang_item(def_id, LangItem::PanicFmt) {
            let const_def_id = self.tcx.require_lang_item(LangItem::ConstPanicFmt, self.tcx.span);