* lisp/subr.el (pop): Use `car-safe'.

* lisp/subr.el (pop): Use `car-safe'.
* lisp/emacs-lisp/byte-opt.el (byte-optimize-form-code-walker): Remove hack
to detect unused `pop' return value.

* lisp/emacs-lisp/advice.el (defadvice): Add indent rule.

* lisp/international/mule-cmds.el: Require CL.
(find-coding-systems-for-charsets): Avoid add-to-list.
(sanitize-coding-system-list): New function, extracted from
select-safe-coding-system-interactively.
(select-safe-coding-system-interactively): Use it.
(read-input-method-name): Accept symbols for `default'.

* lisp/progmodes/python.el (python-nav-beginning-of-block): Remove unused
var `block-regexp'.
(python-nav--forward-sexp): Remove unused var `re-search-fn'.
(python-fill-string): Remove unused var `marker'.
(python-skeleton-add-menu-items): Remove unused var `items'.