From 8e31f53f8a3132c497363bd87f03204d3d7969af Mon Sep 17 00:00:00 2001
From: Neil MacIntosh <neilmac@microsoft.com>
Date: Fri, 29 Jul 2016 11:16:06 -0700
Subject: [PATCH] Building clean with MSVC12.

---
 include/multi_span.h  |  7 ++++---
 include/span.h        | 22 ++++++++++++++++++++--
 include/string_span.h | 23 +----------------------
 tests/span_tests.cpp  |  8 ++++++++
 tests/utils_tests.cpp |  2 +-
 5 files changed, 34 insertions(+), 28 deletions(-)

diff --git a/include/multi_span.h b/include/multi_span.h
index a59c4dc..e35fc33 100644
--- a/include/multi_span.h
+++ b/include/multi_span.h
@@ -1594,12 +1594,13 @@ public:
 // Free functions for manipulating spans
 //
 
+
 // reshape a multi_span into a different dimensionality
 // DimCount and Enabled here are workarounds for a bug in MSVC 2015
 template <typename SpanType, typename... Dimensions2, size_t DimCount = sizeof...(Dimensions2),
-          bool Enabled = (DimCount > 0), typename = std::enable_if_t<Enabled>>
-constexpr multi_span<typename SpanType::value_type, Dimensions2::value...>
-as_multi_span(SpanType s, Dimensions2... dims)
+          bool Enabled = (DimCount > 0), typename = std::enable_if_t<Enabled> >
+constexpr auto
+as_multi_span(SpanType s, Dimensions2... dims) -> multi_span<typename SpanType::value_type, Dimensions2::value...>
 {
     static_assert(details::is_multi_span<SpanType>::value,
                   "Variadic as_multi_span() is for reshaping existing spans.");
diff --git a/include/span.h b/include/span.h
index 4d8e877..44e1b8d 100644
--- a/include/span.h
+++ b/include/span.h
@@ -49,7 +49,8 @@
 #if _MSC_VER <= 1800
 
 #define GSL_MSVC_HAS_VARIADIC_CTOR_BUG
-#define GSL_MSVC_NO_SUPPORT_FOR_MOVE_CTOR_DEFAULT
+#define GSL_MSVC_NO_DEFAULT_MOVE_CTOR
+#define GSL_MSVC_NO_CPP14_STD_EQUAL
 
 // noexcept is not understood
 #ifndef GSL_THROW_ON_CONTRACT_VIOLATION
@@ -57,6 +58,9 @@
 #define noexcept /* nothing */
 #endif
 
+#pragma push_macro("alignof")
+#define alignof __alignof
+
 // turn off some misguided warnings
 #pragma warning(push)
 #pragma warning(disable : 4351) // warns about newly introduced aggregate initializer behavior
@@ -541,7 +545,11 @@ public:
     }
 
     constexpr span(const span& other) noexcept = default;
+#ifndef GSL_MSVC_NO_DEFAULT_MOVE_CTOR
     constexpr span(span&& other) noexcept = default;
+#else
+    constexpr span(span&& other) noexcept : storage_(std::move(other.storage_)) {}
+#endif
 
     template <
         class OtherElementType, std::ptrdiff_t OtherExtent,
@@ -567,8 +575,12 @@ public:
 
     ~span() noexcept = default;
     constexpr span& operator=(const span& other) noexcept = default;
-    constexpr span& operator=(span&& other) noexcept = default;
 
+#ifndef GSL_MSVC_NO_DEFAULT_MOVE_CTOR
+    constexpr span& operator=(span&& other) noexcept = default;
+#else
+    constexpr span& operator=(span&& other) noexcept { storage_ = std::move(other.storage_); return *this; }
+#endif
     // [span.sub], span subviews
     template <std::ptrdiff_t Count>
     constexpr span<element_type, Count> first() const
@@ -669,7 +681,11 @@ template <class ElementType, std::ptrdiff_t FirstExtent, std::ptrdiff_t SecondEx
 constexpr bool operator==(const span<ElementType, FirstExtent>& l,
                           const span<ElementType, SecondExtent>& r)
 {
+#ifdef GSL_MSVC_NO_CPP14_STD_EQUAL
+    return (l.size() == r.size()) && std::equal(l.begin(), l.end(), r.begin());
+#else
     return std::equal(l.begin(), l.end(), r.begin(), r.end());
+#endif
 }
 
 template <class ElementType, std::ptrdiff_t Extent>
@@ -756,6 +772,8 @@ as_writeable_bytes(span<ElementType, Extent> s) noexcept
 #pragma pop_macro("noexcept")
 #endif // GSL_THROW_ON_CONTRACT_VIOLATION
 
+#pragma pop_macro("alignof")
+
 #undef GSL_MSVC_HAS_VARIADIC_CTOR_BUG
 
 #endif // _MSC_VER <= 1800
diff --git a/include/string_span.h b/include/string_span.h
index 0ca3c51..3fe826f 100644
--- a/include/string_span.h
+++ b/include/string_span.h
@@ -24,6 +24,7 @@
 #include "span.h"
 #include <cstring>
 #include <string>
+#include <cstdint>
 
 #ifdef _MSC_VER
 
@@ -313,7 +314,6 @@ public:
     template <class Container,
               class = std::enable_if_t<
                   !details::is_basic_string_span<Container>::value &&
-                  !details::is_span<Container>::value &&
                   std::is_convertible<typename Container::pointer, pointer>::value &&
                   std::is_convertible<typename Container::pointer,
                                       decltype(std::declval<Container>().data())>::value>>
@@ -324,7 +324,6 @@ public:
     template <class Container,
               class = std::enable_if_t<
                   !details::is_basic_string_span<Container>::value &&
-                  !details::is_span<Container>::value &&
                   std::is_convertible<typename Container::pointer, pointer>::value &&
                   std::is_convertible<typename Container::pointer,
                                       decltype(std::declval<Container>().data())>::value>>
@@ -332,26 +331,6 @@ public:
     {
     }
 
-#ifndef GSL_MSVC_HAS_SFINAE_SUBSTITUTION_ICE
-    // from span
-    template <typename OtherValueType, std::ptrdiff_t OtherExtent,
-              typename Dummy = std::enable_if_t<
-                  std::is_convertible<span<OtherValueType, OtherExtent>, impl_type>::value>>
-    constexpr basic_string_span(const span<OtherValueType, OtherExtent>& other) : span_(other)
-    {
-    }
-#else
-    // from span
-    constexpr basic_string_span(span<element_type, Extent> other) : span_(other) {}
-
-    template <typename = std::enable_if_t<
-                  !std::is_same<std::remove_const_t<element_type>, value_type>::value>>
-    constexpr basic_string_span(const span<std::remove_const_t<element_type>, Extent>& other)
-        : span_(other)
-    {
-    }
-#endif
-
     // from string_span
     template <
         class OtherValueType, std::ptrdiff_t OtherExtent,
diff --git a/tests/span_tests.cpp b/tests/span_tests.cpp
index 77b799a..8c9829d 100644
--- a/tests/span_tests.cpp
+++ b/tests/span_tests.cpp
@@ -839,7 +839,9 @@ SUITE(span_tests)
             CHECK(it - beyond == 0);
 
             for (auto& n : s)
+            {
                 CHECK(n == 5);
+            }
         }
     }
 
@@ -881,7 +883,9 @@ SUITE(span_tests)
             CHECK(it - beyond == 0);
 
             for (auto& n : s)
+            {
                 CHECK(n == 5);
+            }
         }
     }
 
@@ -923,7 +927,9 @@ SUITE(span_tests)
             CHECK(it - beyond == 0);
 
             for (auto& n : s)
+            {
                 CHECK(n == 5);
+            }
         }
     }
 
@@ -965,7 +971,9 @@ SUITE(span_tests)
             CHECK(it - beyond == 0);
 
             for (auto& n : s)
+            {
                 CHECK(n == 5);
+            }
         }
     }
 
diff --git a/tests/utils_tests.cpp b/tests/utils_tests.cpp
index a46d6e4..11582de 100644
--- a/tests/utils_tests.cpp
+++ b/tests/utils_tests.cpp
@@ -103,7 +103,7 @@ SUITE(utils_tests)
 
         CHECK(narrow<uint32_t>(int32_t(0)) == 0);
         CHECK(narrow<uint32_t>(int32_t(1)) == 1);
-        CHECK(narrow<uint32_t>(int32_max) == int32_max);
+        CHECK(narrow<uint32_t>(int32_max) == static_cast<uint32_t>(int32_max));
 
         CHECK_THROW(narrow<uint32_t>(int32_t(-1)), narrowing_error);
         CHECK_THROW(narrow<uint32_t>(int32_min), narrowing_error);