updated boost on windows

winx64/include/boost/math/special_functions/detail/bessel_i0.hpp

@@ -15,9 +15,19 @@
 #include <boost/math/tools/big_constant.hpp>
 #include <boost/assert.hpp>
 
+#if defined(__GNUC__) && defined(BOOST_MATH_USE_FLOAT128)
+//
+// This is the only way we can avoid
+// warning: non-standard suffix on floating constant [-Wpedantic]
+// when building with -Wall -pedantic.  Neither __extension__
+// nor #pragma dianostic ignored work :(
+//
+#pragma GCC system_header
+#endif
+
 // Modified Bessel function of the first kind of order zero
 // we use the approximating forms derived in:
-// "Rational Approximations for the Modified Bessel Function of the First Kind – I0(x) for Computations with Double Precision"
+// "Rational Approximations for the Modified Bessel Function of the First Kind - I0(x) for Computations with Double Precision"
 // by Pavel Holoborodko, 
 // see http://www.advanpix.com/2015/11/11/rational-approximations-for-the-modified-bessel-function-of-the-first-kind-i0-computations-double-precision
 // The actual coefficients used are our own, and extend Pavel's work to precision's other than double.
@@ -532,7 +542,7 @@ template <typename T>
 inline T bessel_i0(const T& x)
 {
    typedef mpl::int_<
-      std::numeric_limits<T>::digits == 0 ?
+      ((std::numeric_limits<T>::digits == 0) || (std::numeric_limits<T>::radix != 2)) ?
       0 :
       std::numeric_limits<T>::digits <= 24 ?
       24 :