2 files changed, 11 insertions, 2 deletions

diff --git a/etc/NEWS b/etc/NEWS
index 790cf47fbee..f9ede684085 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -1459,8 +1459,14 @@ displayed with a "spinning bar".
 ** New variable `revert-buffer-in-progress-p' is true while a buffer is
 being reverted, even if the buffer has a local `revert-buffer-function'.
 
-** New variables `delayed-warnings-list' and `delayed-warnings-hook' allow
-deferring warnings until the main command loop is executed.
+---
+** New variables `delayed-warnings-list' and `delayed-warnings-hook'.
+If delayed-warnings-list is non-nil, the command loop calls
+delayed-warnings-hook after post-command-hook.  At present, this is
+only used by Emacs on some platforms to display warnings during
+startup, which might otherwise not be noticed.  This uses the functions
+display-delayed-warnings and collapse-delayed-warnings.
+
 
 +++
 ** `set-auto-mode' now respects mode: local variables at the end of files,
diff --git a/lisp/subr.el b/lisp/subr.el
index e735fd9577d..6c79b3f88e2 100644
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -1884,6 +1884,9 @@ Used from `delayed-warnings-hook' (which see)."
         (push warning collapsed)))
     (setq delayed-warnings-list (nreverse collapsed))))
 
+;; At present this is only really useful for Emacs internals.
+;; Document in the lispref if it becomes generally useful.
+;; Ref http://lists.gnu.org/archive/html/emacs-devel/2012-02/msg00085.html
 (defvar delayed-warnings-hook '(collapse-delayed-warnings
                                 display-delayed-warnings)
   "Normal hook run to process delayed warnings.