From 5359f483bce6e4bc682daf1c4e56912a9517506c Mon Sep 17 00:00:00 2001
From: Dave Abrahams <dave@boostpro.com>
Date: Tue, 13 Jan 2004 19:04:15 +0000
Subject: [PATCH] Workaround for GCC2

[SVN r21695]
---
 include/boost/type_traits/is_abstract.hpp | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/include/boost/type_traits/is_abstract.hpp b/include/boost/type_traits/is_abstract.hpp
index ad0642c..b26d107 100755
--- a/include/boost/type_traits/is_abstract.hpp
+++ b/include/boost/type_traits/is_abstract.hpp
@@ -65,10 +65,14 @@ struct is_abstract_imp
    template<class U>
    static type_traits::yes_type check(...);
 
+   // GCC2 won't even parse this template if we embed the computation
+   // of s1 in the computation of value.
+   BOOST_STATIC_CONSTANT(unsigned, s1 = sizeof(check<T>(0)));
+    
    BOOST_STATIC_CONSTANT(bool, value = 
       (::boost::type_traits::ice_and<
          ::boost::is_class<T>::value,
-         (sizeof(check<T>(0)) == sizeof(type_traits::yes_type))
+         (s1 == sizeof(type_traits::yes_type))
       >::value));
 };