From 8855c59579bb0de5212210662ed8aebff3582d41 Mon Sep 17 00:00:00 2001
From: Neil MacIntosh <neilmac@microsoft.com>
Date: Fri, 15 Jul 2016 17:31:40 -0700
Subject: [PATCH] Added basic compile support for MSVC 2013 to byte.

---
 include/gsl_byte.h   | 32 ++++++++++++++++++++++++++++++++
 tests/byte_tests.cpp |  1 +
 tests/span_tests.cpp |  9 +++++++++
 3 files changed, 42 insertions(+)

diff --git a/include/gsl_byte.h b/include/gsl_byte.h
index 6e32fef..e2c79c9 100644
--- a/include/gsl_byte.h
+++ b/include/gsl_byte.h
@@ -19,6 +19,23 @@
 #ifndef GSL_BYTE_H
 #define GSL_BYTE_H
 
+#ifdef _MSC_VER
+
+// MSVC 2013 workarounds
+#if _MSC_VER <= 1800
+
+// constexpr is not understood
+#pragma push_macro("constexpr")
+#define constexpr 
+
+// noexcept is not understood 
+#pragma push_macro("noexcept")
+#define noexcept  
+
+#endif // _MSC_VER <= 1800
+
+#endif // _MSC_VER
+
 namespace gsl
 {
     // This is a simple definition for now that allows
@@ -68,4 +85,19 @@ namespace gsl
     
 } // namespace gsl
 
+
+#ifdef _MSC_VER
+
+#if _MSC_VER <= 1800
+
+#undef constexpr
+#pragma pop_macro("constexpr")
+
+#undef noexcept
+#pragma pop_macro("noexcept")
+
+#endif // _MSC_VER <= 1800
+
+#endif // _MSC_VER
+
 #endif // GSL_BYTE_H
\ No newline at end of file
diff --git a/tests/byte_tests.cpp b/tests/byte_tests.cpp
index 19456fd..5d4e7f6 100644
--- a/tests/byte_tests.cpp
+++ b/tests/byte_tests.cpp
@@ -87,6 +87,7 @@ SUITE(byte_tests)
         CHECK(a == byte(0x0F));
     }
 }
+
 }
 
 int main(int, const char* []) { return UnitTest::RunAllTests(); }
diff --git a/tests/span_tests.cpp b/tests/span_tests.cpp
index 5c17552..ae3c32e 100644
--- a/tests/span_tests.cpp
+++ b/tests/span_tests.cpp
@@ -794,6 +794,15 @@ SUITE(span_tests)
         CHECK(it1 == it2);
     }
 
+    TEST(const_iterator)
+    {
+        span<int>::const_iterator it1;
+        span<int>::const_iterator it2;
+        CHECK(it1 == it2);
+
+        
+    }
+
     TEST(begin_end)
     {
         {