From c43a861814c2cbe65c67d0bfa5523b50eba1419f Mon Sep 17 00:00:00 2001
From: Stefan Monnier <monnier@iro.umontreal.ca>
Date: Mon, 22 Jul 2013 13:24:31 -0400
Subject: [PATCH] * lisp/subr.el (add-to-list): Fix compiler-macro when
 `append' is not constant.  Don't use `cl-member' for the base case.

---
 lisp/ChangeLog |  3 +++
 lisp/subr.el   | 21 +++++++++++++--------
 2 files changed, 16 insertions(+), 8 deletions(-)

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index bf243febe4..38c79fc427 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,5 +1,8 @@
 2013-07-22  Stefan Monnier  <monnier@iro.umontreal.ca>
 
+	* subr.el (add-to-list): Fix compiler-macro when `append' is
+	not constant.  Don't use `cl-member' for the base case.
+
 	* progmodes/subword.el: Fix boundary case (bug#13758).
 	(subword-forward-regexp): Make it a constant.  Wrap optional \\W in its
 	own group.
diff --git a/lisp/subr.el b/lisp/subr.el
index 75c6b3a062..7130639dbe 100644
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -1498,9 +1498,10 @@ other hooks, such as major mode hooks, can do the job."
       ;; FIXME: Something like this could be used for `set' as well.
       (if (or (not (eq 'quote (car-safe list-var)))
               (special-variable-p (cadr list-var))
-              (and append compare-fn))
+              (not (macroexp-const-p append)))
           exp
         (let* ((sym (cadr list-var))
+               (append (eval append))
                (msg (format "`add-to-list' can't use lexical var `%s'; use `push' or `cl-pushnew'"
                             sym))
                ;; Big ugly hack so we only output a warning during
@@ -1513,13 +1514,17 @@ other hooks, such as major mode hooks, can do the job."
                           (when (assq sym byte-compile--lexical-environment)
                             (byte-compile-log-warning msg t :error))))
                (code
-                (if append
-                    (macroexp-let2 macroexp-copyable-p x element
-                    `(unless (member ,x ,sym)
-                       (setq ,sym (append ,sym (list ,x)))))
-                  (require 'cl-lib)
-                  `(cl-pushnew ,element ,sym
-                               :test ,(or compare-fn '#'equal)))))
+                (macroexp-let2 macroexp-copyable-p x element
+                  `(unless ,(if compare-fn
+                                (progn
+                                  (require 'cl-lib)
+                                  `(cl-member ,x ,sym :test ,compare-fn))
+                              ;; For bootstrapping reasons, don't rely on
+                              ;; cl--compiler-macro-member for the base case.
+                              `(member ,x ,sym))
+                     ,(if append
+                          `(setq ,sym (append ,sym (list ,x)))
+                        `(push ,x ,sym))))))
           (if (not (macroexp--compiling-p))
               code
             `(progn
-- 
2.20.1