Don't modify interactive closures destructively (Bug#60974).fix/bug-60974

* lisp/emacs-lisp/cconv.el (cconv-convert): When form is an
interactive lambda form, don't destructively modify it, as it might be
a constant literal. Instead, create a new list with the relevant
place(s) changed.

* test/lisp/emacs-lisp/cconv-tests.el
(cconv-tests-interactive-form-modify-bug60974): New test.

1 files changed, 12 insertions, 0 deletions

diff --git a/test/lisp/emacs-lisp/cconv-tests.el b/test/lisp/emacs-lisp/cconv-tests.el
index 349ffeb7e47..6facd3452ea 100644
--- a/test/lisp/emacs-lisp/cconv-tests.el
+++ b/test/lisp/emacs-lisp/cconv-tests.el
@@ -376,6 +376,18 @@
                          (eval '(lambda (x) :closure-dont-trim-context (+ x 1))
                                `((y . ,magic-string)))))))
 
+(ert-deftest cconv-tests-interactive-form-modify-bug60974 ()
+  (let* ((f '(function (lambda (&optional arg)
+                         (interactive
+                          (list (if current-prefix-arg
+                                    (prefix-numeric-value current-prefix-arg)
+                                  'toggle)))
+                         (ignore arg))))
+         (if (cadr (nth 2 (cadr f))))
+         (if2))
+    (cconv-closure-convert f)
+    (setq if2 (cadr (nth 2 (cadr f))))
+    (should (eq if if2))))
 
 (provide 'cconv-tests)
 ;;; cconv-tests.el ends here