This commit was manufactured by cvs2svn to create tag 'v1_4_4'.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/tags/v1_4_4@668 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 7 insertions, 1 deletions

diff --git a/lib/singleton.rb b/lib/singleton.rb
index 8167a01aa8..235ba898fd 100644
--- a/lib/singleton.rb
+++ b/lib/singleton.rb
@@ -14,9 +14,15 @@ module Singleton
   def Singleton.append_features(klass)
     klass.private_class_method(:new)
     klass.instance_eval %{
+      @__instance__ = nil
       def instance
+	Thread.critical = true
 	unless @__instance__
-	  @__instance__ = new
+	  begin
+	    @__instance__ = new
+	  ensure
+	    Thread.critical = false
+	  end
 	end
 	return @__instance__
       end