{"ast_node_type":"variable","tokens":[{"end":77,"kind":"keyword","start":0,"text":"let"}]}
        let callee_features = &self.codegen_fn_attrs(caller).target_features;
        let fun_features = &self.codegen_fn_attrs(fun_def).target_features;
        if self.is_target_feature_call_safe(&fun_features, &callee_features) {