Merge pull request #1228 from wravery/master

Explicit cast from size_t to Slice<T>::iterator::difference_type in cxx.h

include/cxx.h

@@ -659,7 +659,7 @@ typename Slice<T>::iterator::difference_type
 Slice<T>::iterator::operator-(const iterator &other) const noexcept {
   auto diff = std::distance(static_cast<char *>(other.pos),
                             static_cast<char *>(this->pos));
-  return diff / this->stride;
+  return diff / static_cast<typename Slice<T>::iterator::difference_type>(this->stride);
 }
 
 template <typename T>