diff options
Diffstat (limited to 'lisp/simple.el')
| -rw-r--r-- | lisp/simple.el | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/lisp/simple.el b/lisp/simple.el index 68bfd7b14f4..a5e8381eaaa 100644 --- a/lisp/simple.el +++ b/lisp/simple.el @@ -2143,7 +2143,12 @@ as an argument limits undo to changes within the current region." ;; above when checking. (while (eq (car list) nil) (setq list (cdr list))) - (puthash list (if undo-in-region t pending-undo-list) + (puthash list + ;; Prevent identity mapping. This can happen if + ;; consecutive nils are erroneously in undo list. + (if (or undo-in-region (eq list pending-undo-list)) + t + pending-undo-list) undo-equiv-table)) ;; Don't specify a position in the undo record for the undo command. ;; Instead, undoing this should move point to where the change is. |