   (let ((file-line-pos (split-string posn ":")))
     (goto-char (point-min))
     (forward-line (1- (string-to-number (cadr file-line-pos))))
-    (go-guru--goto-byte-column (string-to-number (caddr file-line-pos)))))
+    (go-guru--goto-byte-column (string-to-number (cl-caddr file-line-pos)))))
 
 ;;;###autoload
 (defun go-guru-callees ()

	    (setq start end) ; break out of loop
	  (setq p (1- p)) ; exclude final space
	  (let* ((posn (buffer-substring-no-properties start p))
		 (flen (search ":" posn)) ; length of filename
		 (filename (if (< flen 19)
			       (substring posn 0 flen)
			     (concat "…" (substring posn (- flen 19) flen)))))

(require 'go-mode)
(require 'json)
(require 'simple)
(require 'cl-lib)

(defgroup go-guru nil
  "Options specific to the Go guru."
