Warn against recursive invocations of 'buffer-list-update-hook' (Bug#34765)

* src/buffer.c (Vbuffer_list_update_hook):
* doc/lispref/buffers.texi (Buffer List): Warn against
recursive invocations of 'buffer-list-update-hook' (Bug#34765).

2 files changed, 9 insertions, 3 deletions

diff --git a/doc/lispref/buffers.texi b/doc/lispref/buffers.texi
index d97a095f686..6ad1fb1824a 100644
--- a/doc/lispref/buffers.texi
+++ b/doc/lispref/buffers.texi
@@ -940,6 +940,10 @@ This is a normal hook run whenever the buffer list changes.  Functions
 (@pxref{Creating Buffers}), @code{rename-buffer} (@pxref{Buffer Names}),
 @code{kill-buffer} (@pxref{Killing Buffers}), @code{bury-buffer} (see
 above) and @code{select-window} (@pxref{Selecting Windows}).
+
+Functions run by this hook should avoid calling @code{select-window}
+with a nil @var{norecord} argument or @code{with-temp-buffer} since
+either may lead to infinite recursion.
 @end defvar
 
 @node Creating Buffers
diff --git a/src/buffer.c b/src/buffer.c
index 4ab5d4efe30..12620f0d4aa 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -6236,9 +6236,11 @@ The function `kill-all-local-variables' runs this before doing anything else.  *
 
   DEFVAR_LISP ("buffer-list-update-hook", Vbuffer_list_update_hook,
                doc: /* Hook run when the buffer list changes.
-Functions running this hook are, `get-buffer-create',
-`make-indirect-buffer', `rename-buffer', `kill-buffer',
-`bury-buffer-internal' and `select-window'.  */);
+Functions (implicitly) running this hook are `get-buffer-create',
+`make-indirect-buffer', `rename-buffer', `kill-buffer', `bury-buffer'
+and `select-window'.  Functions run by this hook should avoid calling
+`select-window' with a nil NORECORD argument or `with-temp-buffer'
+since either may lead to infinite recursion.  */);
   Vbuffer_list_update_hook = Qnil;
   DEFSYM (Qbuffer_list_update_hook, "buffer-list-update-hook");