diff --git a/include/boost/mpl/aux_/integral_wrapper.hpp b/include/boost/mpl/aux_/integral_wrapper.hpp
index 6b5962e..6bc05f7 100644
--- a/include/boost/mpl/aux_/integral_wrapper.hpp
+++ b/include/boost/mpl/aux_/integral_wrapper.hpp
@@ -77,7 +77,7 @@ struct AUX_WRAPPER_NAME
     // functions that return objects of both arithmetic ('int', 'long',
     // 'double', etc.) and wrapped integral types (for an example, see 
     // "mpl/example/power.cpp")
-    operator AUX_WRAPPER_VALUE_TYPE() const { return static_cast<AUX_WRAPPER_VALUE_TYPE>(this->value); } 
+    BOOST_CONSTEXPR operator AUX_WRAPPER_VALUE_TYPE() const { return static_cast<AUX_WRAPPER_VALUE_TYPE>(this->value); } 
 };
 
 #if !defined(BOOST_NO_INCLASS_MEMBER_INITIALIZATION)
diff --git a/include/boost/mpl/bool.hpp b/include/boost/mpl/bool.hpp
index f4bb485..0a6180c 100644
--- a/include/boost/mpl/bool.hpp
+++ b/include/boost/mpl/bool.hpp
@@ -26,7 +26,7 @@ template< bool C_ > struct bool_
     typedef integral_c_tag tag;
     typedef bool_ type;
     typedef bool value_type;
-    operator bool() const { return this->value; }
+    BOOST_CONSTEXPR operator bool() const { return this->value; }
 };
 
 #if !defined(BOOST_NO_INCLASS_MEMBER_INITIALIZATION)
diff --git a/include/boost/mpl/string.hpp b/include/boost/mpl/string.hpp
index c62d8ab..345918f 100644
--- a/include/boost/mpl/string.hpp
+++ b/include/boost/mpl/string.hpp
@@ -19,7 +19,7 @@
 
 #include <boost/config.hpp>
 #include <boost/detail/workaround.hpp>
-#include <boost/detail/endian.hpp>
+#include <boost/predef/other/endian.h>
 #include <boost/mpl/limits/string.hpp>
 #include <boost/mpl/if.hpp>
 #include <boost/mpl/char.hpp>
@@ -59,7 +59,7 @@ namespace boost { namespace mpl
     #define BOOST_MPL_MULTICHAR_LENGTH(c)                                                           \
       (std::size_t)((c<CHAR_MIN) ? 4 : ((c>0xffffff)+(c>0xffff)+(c>0xff)+1))
 
-    #if defined(BOOST_LITTLE_ENDIAN) && defined(__SUNPRO_CC)
+    #if defined(BOOST_ENDIAN_LITTLE_BYTE) && defined(__SUNPRO_CC)
 
         #define BOOST_MPL_MULTICHAR_AT(c,i)                                                         \
           (char)(0xff&((unsigned)(c)>>(8*(std::size_t)(i))))
diff --git a/test/bool.cpp b/test/bool.cpp
index 8fad753..e023c0c 100644
--- a/test/bool.cpp
+++ b/test/bool.cpp
@@ -16,11 +16,18 @@
 
 #include <cassert>
 
+#if defined(BOOST_NO_CXX11_CONSTEXPR)
+#define CONSTEXPR_BOOL_TEST(c)
+#else 
+#define CONSTEXPR_BOOL_TEST(c) { static_assert(bool_<c>() == c, "Constexpr for bool_ failed"); }
+#endif
+
 #define BOOL_TEST(c) \
     { MPL_ASSERT(( is_same< bool_<c>::value_type, bool > )); } \
     { MPL_ASSERT(( is_same< bool_<c>, c##_ > )); } \
     { MPL_ASSERT(( is_same< bool_<c>::type, bool_<c> > )); } \
     { MPL_ASSERT_RELATION( bool_<c>::value, ==, c ); } \
+    CONSTEXPR_BOOL_TEST(c) \
     BOOST_TEST( bool_<c>() == c ); \
 /**/
 
diff --git a/test/integral_wrapper_test.hpp b/test/integral_wrapper_test.hpp
index 4a08d3c..be31d50 100644
--- a/test/integral_wrapper_test.hpp
+++ b/test/integral_wrapper_test.hpp
@@ -28,6 +28,12 @@
     /**/
 #endif
 
+#if defined(BOOST_NO_CXX11_CONSTEXPR)
+#define CONSTEXPR_INTEGRAL_TEST(T, i)
+#else 
+#define CONSTEXPR_INTEGRAL_TEST(T, i) { static_assert(T() == i, "Constexpr for integral constant failed"); }
+#endif
+
 #if BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x582))
 // agurt 20/nov/06: see http://article.gmane.org/gmane.comp.lib.boost.devel/151065
 #define INTEGRAL_WRAPPER_TEST(unused1, i, T) \
@@ -39,6 +45,7 @@
     { MPL_ASSERT(( is_same< next< borland_tested_type >::type, WRAPPER(T,i+1) > )); } \
     { MPL_ASSERT(( is_same< prior< borland_tested_type >::type, WRAPPER(T,i-1) > )); } \
     { MPL_ASSERT_RELATION( (borland_tested_type::value), ==, i ); } \
+    CONSTEXPR_INTEGRAL_TEST(borland_tested_type, i) \
     INTEGRAL_WRAPPER_RUNTIME_TEST(i, T) \
     } \
 /**/
@@ -49,6 +56,7 @@
     { MPL_ASSERT(( is_same< next< WRAPPER(T,i) >::type, WRAPPER(T,i+1) > )); } \
     { MPL_ASSERT(( is_same< prior< WRAPPER(T,i) >::type, WRAPPER(T,i-1) > )); } \
     { MPL_ASSERT_RELATION( (WRAPPER(T,i)::value), ==, i ); } \
+    CONSTEXPR_INTEGRAL_TEST(WRAPPER(T,i), i) \
     INTEGRAL_WRAPPER_RUNTIME_TEST(i, T) \
 /**/
 #endif