gnus-util.el (gnus-macroexpand-all): Don't modify argument.

[bpt/emacs.git] / lisp / gnus / gnus-util.el

diff --git a/lisp/gnus/gnus-util.el b/lisp/gnus/gnus-util.el
index af5159e..1f391f0 100644 (file)
--- a/lisp/gnus/gnus-util.el
+++ b/lisp/gnus/gnus-util.el
@@ -2041,7 +2041,7 @@ Same as `string-match' except this function does not change the match data."
 If no macros are expanded, FORM is returned unchanged."
     (if (consp form)
        (let ((idx 1)
 If no macros are expanded, FORM is returned unchanged."
     (if (consp form)
        (let ((idx 1)

-             (len (length form))
+             (len (length (setq form (copy-sequence form))))

              expanded)
          (while (< idx len)
            (setcar (nthcdr idx form) (gnus-macroexpand-all (nth idx form)))
              expanded)
          (while (< idx len)
            (setcar (nthcdr idx form) (gnus-macroexpand-all (nth idx form)))