diff --git a/include/boost/integer/integer_mask.hpp b/include/boost/integer/integer_mask.hpp
index 0a092d3..8c4e1bb 100644
--- a/include/boost/integer/integer_mask.hpp
+++ b/include/boost/integer/integer_mask.hpp
@@ -70,6 +70,11 @@ struct low_bits_mask_t
       BOOST_STATIC_CONSTANT( std::size_t, bit_count = limits_type::digits );    \
   }
 
+#ifdef BOOST_MSVC
+#pragma warning(push)
+#pragma warning(disable:4245)  // 'initializing' : conversion from 'int' to 'const boost::low_bits_mask_t<8>::least', signed/unsigned mismatch
+#endif
+
 BOOST_LOW_BITS_MASK_SPECIALIZE( unsigned char );
 
 #if USHRT_MAX > UCHAR_MAX
@@ -84,6 +89,10 @@ BOOST_LOW_BITS_MASK_SPECIALIZE( unsigned int );
 BOOST_LOW_BITS_MASK_SPECIALIZE( unsigned long );
 #endif
 
+#ifdef BOOST_MSVC
+#pragma warning(pop)
+#endif
+
 #undef BOOST_LOW_BITS_MASK_SPECIALIZE
 
 
diff --git a/include/boost/integer_traits.hpp b/include/boost/integer_traits.hpp
index 96b3526..8011618 100644
--- a/include/boost/integer_traits.hpp
+++ b/include/boost/integer_traits.hpp
@@ -27,6 +27,17 @@
 #include <wchar.h>
 #endif
 
+//
+// We simply cannot include this header on gcc without getting copious warnings of the kind:
+//
+// ../../../boost/integer_traits.hpp:164:66: warning: use of C99 long long integer constant
+//
+// And yet there is no other reasonable implementation, so we declare this a system header
+// to suppress these warnings.
+//
+#if defined(__GNUC__) && (__GNUC__ >= 4)
+#pragma GCC system_header
+#endif
 
 namespace boost {
 template<class T>
diff --git a/test/integer_mask_test.cpp b/test/integer_mask_test.cpp
index 38f5211..8e0c11a 100644
--- a/test/integer_mask_test.cpp
+++ b/test/integer_mask_test.cpp
@@ -17,6 +17,9 @@
 
 #include <iostream>  // for std::cout (std::endl indirectly)
 
+#ifdef BOOST_MSVC
+#pragma warning(disable:4127) // conditional expression is constant
+#endif
 
 #define PRIVATE_HIGH_BIT_SLOW_TEST(v)  BOOST_CHECK( ::boost::high_bit_mask_t< \
  (v) >::high_bit == (1ul << (v)) );
@@ -25,10 +28,20 @@
 #define PRIVATE_HIGH_BIT_TEST(v)  do { PRIVATE_HIGH_BIT_SLOW_TEST(v); \
  PRIVATE_HIGH_BIT_FAST_TEST(v); } while (false)
 
-#define PRIVATE_LOW_BITS_SLOW_TEST(v)  BOOST_CHECK( ::boost::low_bits_mask_t< \
- (v) >::sig_bits == ((1ul << (v)) - 1) );
-#define PRIVATE_LOW_BITS_FAST_TEST(v)  BOOST_CHECK( ::boost::low_bits_mask_t< \
- (v) >::sig_bits_fast == ((1ul << (v)) - 1) );
+#define PRIVATE_LOW_BITS_SLOW_TEST(v)  \
+   do{ \
+      unsigned long mask = 0;\
+      if(v > 0)\
+         { mask = ((1ul << (v-1)) - 1); mask <<= 1; mask |= 1; }\
+      BOOST_CHECK( ::boost::low_bits_mask_t< (v) >::sig_bits ==  mask); \
+   }while(false);
+#define PRIVATE_LOW_BITS_FAST_TEST(v)  \
+   do{ \
+      unsigned long mask = 0;\
+      if(v > 0)\
+         { mask = ((1ul << (v-1)) - 1); mask <<= 1; mask |= 1; }\
+      BOOST_CHECK( ::boost::low_bits_mask_t< (v) >::sig_bits_fast == mask);\
+   }while(false);
 #define PRIVATE_LOW_BITS_TEST(v)  do { PRIVATE_LOW_BITS_SLOW_TEST(v); \
  PRIVATE_LOW_BITS_FAST_TEST(v); } while (false)
 
@@ -73,7 +86,7 @@ int test_main( int, char*[] )
     PRIVATE_HIGH_BIT_TEST(  0 );
 
     cout << "Doing low_bits_mask_t tests." << endl;
-    PRIVATE_LOW_BITS_TEST( 32 );  // Undefined behavior?  Whoops!
+    PRIVATE_LOW_BITS_TEST( 32 );
     PRIVATE_LOW_BITS_TEST( 31 );
     PRIVATE_LOW_BITS_TEST( 30 );
     PRIVATE_LOW_BITS_TEST( 29 );
diff --git a/test/integer_test.cpp b/test/integer_test.cpp
index 6bfff11..ba6a4bb 100644
--- a/test/integer_test.cpp
+++ b/test/integer_test.cpp
@@ -22,6 +22,10 @@
 #include <iostream>  // for std::cout (std::endl indirectly)
 #include <typeinfo>  // for std::type_info
 
+#ifdef BOOST_MSVC
+#pragma warning(disable:4127) // conditional expression is constant
+#endif
+
 
 // Control if the names of the types for each version
 // of the integer templates will be printed.