Fix another case of freed markers in the undo-list (Bug#30931)

* src/alloc.c (free_marker): Remove.
* src/editfns.c (save_restriction_restore):
* src/insdel.c (signal_before_change): Detach the markers from the
buffer when we're done with them instead of calling free_marker on
them.
* test/src/editfns-tests.el (delete-region-undo-markers-1)
(delete-region-undo-markers-2): New tests.

(cherry picked from commit 96b8747d5c5d747af13fd84d8fe0308ef2a0ea7a)

1 files changed, 0 insertions, 9 deletions

diff --git a/src/alloc.c b/src/alloc.c
index c3f7920ed87..09d61b7e5f3 100644
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -3884,15 +3884,6 @@ build_marker (struct buffer *buf, ptrdiff_t charpos, ptrdiff_t bytepos)
   return obj;
 }
 
-/* Put MARKER back on the free list after using it temporarily.  */
-
-void
-free_marker (Lisp_Object marker)
-{
-  unchain_marker (XMARKER (marker));
-  free_misc (marker);
-}
-
 
 /* Return a newly created vector or string with specified arguments as
    elements.  If all the arguments are characters that can fit