Address some compilation warnings.

* lisp/international/mule-cmds.el (w32-get-console-codepage)
(w32-get-console-output-codepage):
* lisp/progmodes/elisp-mode.el (xref-collect-references):
* lisp/version.el (cairo-version-string): Declare.

* lisp/erc/erc.el (erc-nickname-in-use): Fix typo.

lisp/erc/erc.el

@@ -4185,7 +4185,7 @@ See also `erc-display-error-notice'."
                                    ;; server's setting if we haven't
                                    ;; established a connection yet
                                    (- 9 (length erc-nick-uniquifier))))
-				erc-nick-uniqifier)))
+				erc-nick-uniquifier)))
       (erc-cmd-NICK newnick)
       (erc-display-error-notice
        nil

lisp/international/mule-cmds.el

@@ -2519,6 +2519,9 @@ is returned.  Thus, for instance, if charset \"ISO8859-2\",
 ;; too, for setting things such as calendar holidays, ps-print paper
 ;; size, spelling dictionary.
 
+(declare-function w32-get-console-codepage "w32proc.c" ())
+(declare-function w32-get-console-output-codepage "w32proc.c" ())
+
 (defun locale-translate (locale)
   "Expand LOCALE according to `locale-translation-file-name', if possible.
 For example, translate \"swedish\" into \"sv_SE.ISO8859-1\"."

lisp/progmodes/elisp-mode.el

@@ -582,6 +582,7 @@ It can be quoted, or be inside a quoted form."
 (declare-function xref-make-bogus-location "xref" (message))
 (declare-function xref-make "xref" (description location))
 (declare-function xref-collect-matches "xref" (input dir &optional kind))
+(declare-function xref-collect-references "xref" (symbol dir))
 
 (defun elisp-xref-find (action id)
   (require 'find-func)

lisp/version.el

@@ -47,6 +47,7 @@ This variable first existed in version 19.23.")
 (defvar motif-version-string)
 (defvar gtk-version-string)
 (defvar ns-version-string)
+(defvar cairo-version-string)
 
 (defun emacs-version (&optional here)
   "Return string describing the version of Emacs that is running.