diff --git a/lisp/progmodes/js.el b/lisp/progmodes/js.el
index a35c4a31d06..40f60c9277a 100644
--- a/lisp/progmodes/js.el
+++ b/lisp/progmodes/js.el
@@ -62,7 +62,7 @@
 (defvar moz-repl-name)
 (defvar ido-cur-list)
 (defvar electric-layout-rules)
-(declare-function ido-mode "ido")
+(declare-function ido-mode "ido" (arg))
 (declare-function inferior-moz-process "ext:mozrepl" ())
 
 ;;; Constants
diff --git a/lisp/w32-fns.el b/lisp/w32-fns.el
index 4815f4b8c21..91c02530427 100644
--- a/lisp/w32-fns.el
+++ b/lisp/w32-fns.el
@@ -31,9 +31,9 @@
 
 ;;;; Function keys
 
-(declare-function set-message-beep "w32fns.c")
-(declare-function w32-get-locale-info "w32proc.c")
-(declare-function w32-get-valid-locale-ids "w32proc.c")
+(declare-function set-message-beep "w32fns.c" (sound))
+(declare-function w32-get-locale-info "w32proc.c" (lcid &optional longform))
+(declare-function w32-get-valid-locale-ids "w32proc.c" ())
 
 ;; Map all versions of a filename (8.3, longname, mixed case) to the
 ;; same buffer.