{"ast_node_type":"variable","tokens":[{"end":93,"kind":"keyword","start":0,"text":"let"}]}
                let safe_span = source_map.span_until_non_whitespace(safe_span.to(sig.span));
                let source_map = self.sess.psess.source_map();
                dcx.emit_err(errors::AbiCustomSafeForeignFunction { span: sig.span, safe_span });