Allow thread's buffer to be killed, by default

* src/thread.c (Fmake_thread): Add new argument (bug#76969).
(thread_set_error): New function, extracted from thread-signal.
(Fthread_buffer_disposition): Add getter.
(Fthread_set_buffer_disposition): And setter.
(thread_check_current_buffer): Check the values of threads'
buffer_disposition.
(thread_all_before_buffer_killed): New function.
(init_threads): Set buffer_disposition to nil for the main thread.
(syms_of_threads): Add new symbols and define the error.

* src/thread.h (thread_state): New field buffer_disposition.
(thread_all_before_buffer_killed): Declare.

* src/buffer.c (Fkill_buffer): Call thread_check_current_buffer
one more time after all hooks and after that call
thread_all_before_buffer_killed.

* src/comp.c (ABI_VERSION): Increase the value.

* test/src/thread-tests.el (thread-buffer-disposition-t)
(thread-buffer-disposition-nil)
(thread-buffer-disposition-silently)
(thread-set-buffer-disposition)
(thread-set-buffer-disposition-main-thread): New tests.

* doc/lispref/threads.texi (Basic Thread Functions): Document
buffer-disposition in make-thread and its getter and setter.

* etc/NEWS: Add entry.

1 files changed, 7 insertions, 0 deletions

diff --git a/src/buffer.c b/src/buffer.c
index a465153279d..e44b6daf587 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -2050,6 +2050,13 @@ cleaning up all windows currently displaying the buffer to be killed. */)
         return Qnil;
     }
 
+  /* Check all threads again, in case a hook changed something.  */
+  if (thread_check_current_buffer (b))
+    return Qnil;
+
+  /* Clean up references to the buffer in threads.  */
+  thread_all_before_buffer_killed (buffer);
+
   /* If the buffer now current is shown in the minibuffer and our buffer
      is the sole other buffer give up.  */
   XSETBUFFER (tem, current_buffer);