1 files changed, 19 insertions, 12 deletions
diff --git a/boost/safe_numerics/checked_default.hpp b/boost/safe_numerics/checked_default.hpp
index 5a5bb44d24..07699c4fca 100644
--- a/boost/safe_numerics/checked_default.hpp
+++ b/boost/safe_numerics/checked_default.hpp
@@ -1,11 +1,6 @@
 #ifndef BOOST_NUMERIC_CHECKED_DEFAULT_HPP
 #define BOOST_NUMERIC_CHECKED_DEFAULT_HPP
 
-// MS compatible compilers support #pragma once
-#if defined(_MSC_VER) && (_MSC_VER >= 1020)
-# pragma once
-#endif
-
 //  Copyright (c) 2017 Robert Ramey
 //
 // Distributed under the Boost Software License, Version 1.0. (See
@@ -49,14 +44,27 @@ namespace safe_numerics {
 // it should trap with a static_assert. This occurs at compile time while
 // calculating result interval.  This needs more investigation.
 
-template<typename R, typename T = void, class Default = void>
-struct checked_operation{
+template<
+    typename R,
+    typename T,
+    class F = make_checked_result<R>,
+    class Default = void
+>
+struct heterogeneous_checked_operation {
     constexpr static checked_result<R>
     cast(const T & t) /* noexcept */ {
         return static_cast<R>(t);
     }
-    constexpr static checked_result<T>
-    minus(const T & t) noexcept {
+};
+
+template<
+    typename R,
+    class F = make_checked_result<R>,
+    class Default = void
+>
+struct checked_operation{
+    constexpr static checked_result<R>
+    minus(const R & t) noexcept {
         return - t;
     }
     constexpr static checked_result<R>
@@ -124,7 +132,7 @@ namespace checked {
 
 template<typename R, typename T>
 constexpr checked_result<R> cast(const T & t) /* noexcept */ {
-    return checked_operation<R, T>::cast(t);
+    return heterogeneous_checked_operation<R, T>::cast(t);
 }
 template<typename R>
 constexpr checked_result<R> minus(const R & t) noexcept {
@@ -184,7 +192,7 @@ constexpr checked_result<R> bitwise_or(const R & t, const R & u) noexcept {
 }
 template<typename R>
 constexpr checked_result<R> bitwise_xor(const R & t, const R & u) noexcept {
-    return checked_operation<R>::bitwise_or(t, u);
+    return checked_operation<R>::bitwise_xor(t, u);
 }
 template<typename R>
 constexpr checked_result<R> bitwise_and(const R & t, const R & u) noexcept {
@@ -200,4 +208,3 @@ constexpr checked_result<R> bitwise_not(const R & t) noexcept {
 } // boost
 
 #endif // BOOST_NUMERIC_CHECKED_DEFAULT_HPP
-