message: Workaround MSVC bug in span.hpp
  Fixes
diff: @@ -144,7 +144,7 @@ namespace ranges
  std::is_convertible<concepts::ContiguousRange::element_t<Rng>(*)[], T(*)[]>>;
  template<typename Rng>
  using DynamicConversion = meta::bool_<
  - N == dynamic_extent || (range_cardinality<Rng>::value < cardinality{})>;
  + N == dynamic_extent || (range_cardinality<Rng>::value < cardinality())>;
  template<typename Rng,
  // This multiple-CONCEPT_REQUIRES_ form works around a gcc 4.9 bug.
  @@ -331,7 +331,7 @@ namespace ranges
  CONCEPT_REQUIRES_(ContiguousRange<Rng>())>
  span(Rng &&rng) ->
  span<concepts::ContiguousRange::element_t<Rng>,
  - (range_cardinality<Rng>::value < cardinality{}
  + (range_cardinality<Rng>::value < cardinality()
  ? dynamic_extent
  : static_cast<detail::span_index_t>(range_cardinality<Rng>::value))>;
  #endif
  @@ -363,7 +363,7 @@ namespace ranges
  }
  template<typename Rng,
  CONCEPT_REQUIRES_(ContiguousRange<Rng>() &&
  - range_cardinality<Rng>::value < cardinality{})>
  + range_cardinality<Rng>::value < cardinality())>
  constexpr span<concepts::ContiguousRange::element_t<Rng>>
  make_span(Rng &&rng)
  noexcept(noexcept(ranges::data(rng), ranges::size(rng)))
  @@ -373,7 +373,7 @@ namespace ranges
  }
  template<typename Rng,
  CONCEPT_REQUIRES_(ContiguousRange<Rng>() &&
  - range_cardinality<Rng>::value >= cardinality{})>
  + range_cardinality<Rng>::value >= cardinality())>
  constexpr span<concepts::ContiguousRange::element_t<Rng>,
  static_cast<detail::span_index_t>(range_cardinality<Rng>::value)>
  make_span(Rng &&rng)
  