Run most of the unordered container tests (not the exception tests) on warning

level 4 on Visual C++.


[SVN r38648]

test/helpers/invariants.hpp

@@ -15,6 +15,11 @@
 #include "./helpers.hpp"
 #include "./allocator.hpp"
 
+#if defined(BOOST_MSVC)
+#pragma warning(push)
+#pragma warning(disable:4127) // conditional expression is constant
+#endif
+
 namespace test
 {
     template <class X>
@@ -92,5 +97,9 @@ namespace test
     }
 }
 
+#if defined(BOOST_MSVC)
+#pragma warning(pop)
+#endif
+
 #endif