diff --git a/ChangeLog b/ChangeLog
index c7f066f6e2..83c6aa4d95 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Tue Dec  7 22:29:45 2010  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* lib/optparse.rb (OptionParser::Completion#candidate),
+	  (OptionParser::Switch#compsys): remove unused variables.
+
 Tue Dec  7 22:05:25 2010  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* transcode.c (transcode_loop): call default handler of the given
diff --git a/lib/optparse.rb b/lib/optparse.rb
index 259aa06aa9..b2c9526598 100644
--- a/lib/optparse.rb
+++ b/lib/optparse.rb
@@ -229,7 +229,6 @@ class OptionParser
 
     def self.candidate(key, icase = false, pat = nil, &block)
       pat ||= Completion.regexp(key, icase)
-      canon, sw, cn = nil
       candidates = []
       block.call do |k, *v|
         (if Regexp === k
@@ -442,7 +441,7 @@ class OptionParser
     end
 
     def compsys(sdone, ldone)   # :nodoc:
-      sopts, lopts, s = [], [], nil
+      sopts, lopts = [], []
       @short.each {|s| sdone.fetch(s) {sopts << s}; sdone[s] = true} if @short
       @long.each {|s| ldone.fetch(s) {lopts << s}; ldone[s] = true} if @long
       return if sopts.empty? and lopts.empty? # completely hidden