From: Jérémie Laval <jeremie.laval@gmail.com>
Date: Fri, 22 Oct 2010 14:15:18 +0000 (+0100)
Subject: Use test-and-test-and-set pattern in LazyInitializer::EnsureInitialized
X-Git-Url: http://wien.tomnetworks.com/gitweb/?a=commitdiff_plain;h=adedfedd00fae63a04d3d7e1c03693b7dff6781a;p=mono.git

Use test-and-test-and-set pattern in LazyInitializer::EnsureInitialized
---

diff --git a/mcs/class/corlib/System.Threading/LazyInitializer.cs b/mcs/class/corlib/System.Threading/LazyInitializer.cs
index c63126ee573..9b4ada957ac 100644
--- a/mcs/class/corlib/System.Threading/LazyInitializer.cs
+++ b/mcs/class/corlib/System.Threading/LazyInitializer.cs
@@ -39,7 +39,8 @@ namespace System.Threading
 		
 		public static T EnsureInitialized<T> (ref T target, Func<T> initFunc) where T : class
 		{
-			Interlocked.CompareExchange (ref target, initFunc (), null);
+			if (target == null)
+				Interlocked.CompareExchange (ref target, initFunc (), null);
 			
 			return target;
 		}