Avoid crashes due to base-less indirect buffer

* src/buffer.c (Fkill_buffer): Prevent killing a buffer if its
indirect buffer refuses to be killed.  (Bug#69529)

1 files changed, 10 insertions, 2 deletions

diff --git a/src/buffer.c b/src/buffer.c
index 126f3eb055a..9f55a8813fa 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -1971,8 +1971,16 @@ cleaning up all windows currently displaying the buffer to be killed. */)
       Lisp_Object tail, other;
 
       FOR_EACH_LIVE_BUFFER (tail, other)
-        if (XBUFFER (other)->base_buffer == b)
-          Fkill_buffer (other);
+        {
+          struct buffer *obuf = XBUFFER (other);
+          if (obuf->base_buffer == b)
+            {
+              Fkill_buffer (other);
+              if (BUFFER_LIVE_P (obuf))
+                error ("Unable to kill buffer whose indirect buffer `%s' cannot be killed",
+                       SDATA (BVAR (obuf, name)));
+            }
+        }
 
       /* Exit if we now have killed the base buffer (Bug#11665).  */
       if (!BUFFER_LIVE_P (b))