emacs-29 dc7acb1aafe: Avoid errors in 'delete-forward-char' deleting static compositions

[Eli Zaretskii]

branch: emacs-29
commit dc7acb1aafe9b0b84481ac51a5bd5125d263537e
Author: Eli Zaretskii <eliz@gnu.org>
Commit: Eli Zaretskii <eliz@gnu.org>

    Avoid errors in 'delete-forward-char' deleting static compositions
    
    * lisp/simple.el (delete-forward-char): Fix recognition of static
    compositions.  (Bug#63837)
---
 lisp/simple.el | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lisp/simple.el b/lisp/simple.el
index 3f88fcb8d03..9df5958a168 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -1520,7 +1520,8 @@ the actual saved text might be different from what was 
killed."
                        (let ((from (car cmp))
                              (to (cadr cmp)))
                          (cond
-                          ((= (length cmp) 2) ; static composition
+                          ((and (= (length cmp) 3) ; static composition
+                                (booleanp (nth 2 cmp)))
                            to)
                           ;; TO can be at POS, in which case we want
                           ;; to make sure we advance at least by 1