(rmail-set-attribute): Do nothing if MSGNUM is 0.

1 files changed, 25 insertions, 24 deletions

diff --git a/lisp/mail/rmail.el b/lisp/mail/rmail.el
index 69e4b39e45d..8279adaad24 100644
--- a/lisp/mail/rmail.el
+++ b/lisp/mail/rmail.el
@@ -1109,30 +1109,31 @@ argument causes us to read a file name and use that file as the inbox."
         (omin (point-min-marker))
         (buffer-read-only nil))
     (or msgnum (setq msgnum rmail-current-message))
-    (unwind-protect
-        (save-excursion
-          (widen)
-          (goto-char (+ 3 (rmail-msgbeg msgnum)))
-          (let ((curstate
-                 (not
-                  (null (search-backward (concat ", " attr ",")
-                                         (prog1 (point) (end-of-line)) t)))))
-            (or (eq curstate (not (not state)))
-                (if curstate
-                    (delete-region (point) (1- (match-end 0)))
-                  (beginning-of-line)
-                  (forward-char 2)
-                  (insert " " attr ","))))
-          (if (string= attr "deleted")
-              (rmail-set-message-deleted-p msgnum state)))
-      ;; Note: we don't use save-restriction because that does not work right
-      ;; if changes are made outside the saved restriction
-      ;; before that restriction is restored.
-      (narrow-to-region omin omax)
-      (set-marker omin nil)
-      (set-marker omax nil)
-      (if (= msgnum rmail-current-message)
-          (rmail-display-labels)))))
+    (if (> msgnum 0)
+        (unwind-protect
+            (save-excursion
+              (widen)
+              (goto-char (+ 3 (rmail-msgbeg msgnum)))
+              (let ((curstate
+                     (not
+                      (null (search-backward (concat ", " attr ",")
+                                             (prog1 (point) (end-of-line)) t)))))
+                (or (eq curstate (not (not state)))
+                    (if curstate
+                        (delete-region (point) (1- (match-end 0)))
+                      (beginning-of-line)
+                      (forward-char 2)
+                      (insert " " attr ","))))
+              (if (string= attr "deleted")
+                  (rmail-set-message-deleted-p msgnum state)))
+          ;; Note: we don't use save-restriction because that does not work right
+          ;; if changes are made outside the saved restriction
+          ;; before that restriction is restored.
+          (narrow-to-region omin omax)
+          (set-marker omin nil)
+          (set-marker omax nil)
+          (if (= msgnum rmail-current-message)
+              (rmail-display-labels))))))
 
 ;; Return t if the attributes/keywords line of msg number MSG
 ;; contains a match for the regexp LABELS.