savehist: Take care not to set nil

diff --git a/lisp/savehist.el b/lisp/savehist.el
index cb680dcfd9bcd065f4a3b038b1839fec1f4545a3..2ffb6731be690e2b00ad04a7f40e8406c6216719 100644 (file)
--- a/lisp/savehist.el
+++ b/lisp/savehist.el
@@ -222,6 +222,7 @@ Normally invoked by calling `savehist-mode' to unset the minor mode."
   (savehist--manage-timer))
 
 (defvar savehist--has-given-file-warning nil)
+
 (defun savehist-save ()
   "Save the values of minibuffer history variables.
 Unbound symbols referenced in `savehist-additional-variables' are ignored."
@@ -242,7 +243,7 @@ Unbound symbols referenced in `savehist-additional-variables' are ignored."
       (prin1
        (seq-keep
         (lambda (sym)
-          (and (boundp sym)
+          (and sym (boundp sym)
                (not (memq sym savehist-ignored-variables))
                (readablep (symbol-value sym))
                (cons sym (symbol-value sym))))