From 042d3e08b8e55656a69adfa0382aee13bdde7b3a Mon Sep 17 00:00:00 2001
From: Jens Maurer <jens.maurer@gmx.net>
Date: Wed, 9 Jul 2003 23:13:40 +0000
Subject: [PATCH] fix compilation guard for "using std::swap"

[SVN r19009]
---
 include/boost/optional.hpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/include/boost/optional.hpp b/include/boost/optional.hpp
index ec4a209..45d1196 100644
--- a/include/boost/optional.hpp
+++ b/include/boost/optional.hpp
@@ -296,7 +296,8 @@ void optional_swap ( optional<T>& x, optional<T>& y )
   }
   else if ( !!x && !!y )
   {
-#ifndef __GNUC__
+#ifndef BOOST_NO_STDC_NAMESPACE
+    // allow for Koenig lookup
     using std::swap ;
 #endif
     swap(*x,*y);