Index: boost/lexical_cast.hpp
===================================================================
--- boost/lexical_cast.hpp	(revision 82179)
+++ boost/lexical_cast.hpp	(working copy)
@@ -1870,7 +1870,7 @@
 #elif defined( __BORLANDC__ )
 # pragma option push -w-8041
 #endif
-                    utype const comp_val = static_cast<utype>(-(std::numeric_limits<Type>::min)());
+                    utype const comp_val = static_cast<utype>(1) << std::numeric_limits<Type>::digits;
                     succeed = succeed && out_tmp<=comp_val;
                     output = -out_tmp;
 #if (defined _MSC_VER)