From e7a79b31eaca464f37d346ebeb26be9d9bb1437b Mon Sep 17 00:00:00 2001
From: bolero-MURAKAMI <bolero.murakami@gmail.com>
Date: Fri, 12 Feb 2016 21:06:06 +0900
Subject: [PATCH] partial support (C++11 constexpr) for VC++2015

---
 sprout/cinttypes/div.hpp           |  4 ++--
 sprout/config/compiler/visualc.hpp |  6 +++++-
 sprout/config/suffix.hpp           | 16 ++++++++++++----
 sprout/cstdlib/div.hpp             |  2 +-
 sprout/type/string/to_string.hpp   |  2 +-
 5 files changed, 21 insertions(+), 9 deletions(-)

diff --git a/sprout/cinttypes/div.hpp b/sprout/cinttypes/div.hpp
index 70279689..9ac69dc3 100644
--- a/sprout/cinttypes/div.hpp
+++ b/sprout/cinttypes/div.hpp
@@ -59,7 +59,7 @@ namespace sprout {
 			typename sprout::detail::div_t_traits2<T>::type
 		>::type
 		div_impl2(T const& numer, T const& denom) {
-#if defined(_MSC_VER)
+#if defined(_MSC_VER) && (_MSC_VER > 1900)
 			typename sprout::detail::div_t_traits2<T>::type result = {numer / denom, numer % denom};
 			return result;
 #else
@@ -73,7 +73,7 @@ namespace sprout {
 			typename sprout::detail::div_t_traits2<T>::type
 		>::type
 		div_impl2(T const& numer, T const& denom) {
-#if defined(_MSC_VER)
+#if defined(_MSC_VER) && (_MSC_VER > 1900)
 			typename sprout::detail::div_t_traits2<T>::type result = {numer % denom, numer / denom};
 			return result;
 #else
diff --git a/sprout/config/compiler/visualc.hpp b/sprout/config/compiler/visualc.hpp
index 4f7fc2ee..a1e6f9b8 100644
--- a/sprout/config/compiler/visualc.hpp
+++ b/sprout/config/compiler/visualc.hpp
@@ -8,7 +8,11 @@
 #ifndef SPROUT_CONFIG_COMPILER_VISUALC_HPP
 #define SPROUT_CONFIG_COMPILER_VISUALC_HPP
 
-#define SPROUT_NO_CXX11_CONSTEXPR
+#if _MSC_FULL_VER < 190023026
+#	define SPROUT_NO_CXX11_CONSTEXPR
+#endif
+#define SPROUT_NO_STATIC_CONSTEXPR_INITIALIZATION
+
 #if _MSC_FULL_VER < 180020827
 #	define SPROUT_NO_CXX11_DEFAULTED_FUNCTIONS
 #	define SPROUT_NO_CXX11_DELETED_FUNCTIONS
diff --git a/sprout/config/suffix.hpp b/sprout/config/suffix.hpp
index d4f22c38..9697841f 100644
--- a/sprout/config/suffix.hpp
+++ b/sprout/config/suffix.hpp
@@ -17,11 +17,19 @@
 //
 #ifndef SPROUT_CONFIG_DISABLE_CONSTEXPR
 #	define SPROUT_CONSTEXPR constexpr
-#	define SPROUT_CONSTEXPR_OR_CONST constexpr
-#	define SPROUT_STATIC_CONSTEXPR static constexpr
+#	ifndef SPROUT_NO_STATIC_CONSTEXPR_INITIALIZATION
+#		define SPROUT_CONSTEXPR_OR_CONST constexpr
+#		define SPROUT_STATIC_CONSTEXPR static constexpr
 #
-#	define SPROUT_STATIC_CONSTEXPR_DATA_MEMBER_INNER(EXPR) = EXPR
-#	define SPROUT_STATIC_CONSTEXPR_DATA_MEMBER_OUTER(EXPR)
+#		define SPROUT_STATIC_CONSTEXPR_DATA_MEMBER_INNER(EXPR) = EXPR
+#		define SPROUT_STATIC_CONSTEXPR_DATA_MEMBER_OUTER(EXPR)
+#	else
+#		define SPROUT_CONSTEXPR_OR_CONST const
+#		define SPROUT_STATIC_CONSTEXPR static const
+#
+#		define SPROUT_STATIC_CONSTEXPR_DATA_MEMBER_INNER(EXPR)
+#		define SPROUT_STATIC_CONSTEXPR_DATA_MEMBER_OUTER(EXPR) = EXPR
+#	endif
 #else	// #ifndef SPROUT_CONFIG_DISABLE_CONSTEXPR
 #	define SPROUT_CONSTEXPR
 #	define SPROUT_CONSTEXPR_OR_CONST const
diff --git a/sprout/cstdlib/div.hpp b/sprout/cstdlib/div.hpp
index c5b482d4..fbf6b16b 100644
--- a/sprout/cstdlib/div.hpp
+++ b/sprout/cstdlib/div.hpp
@@ -56,7 +56,7 @@ namespace sprout {
 			typename sprout::detail::div_t_traits<T>::type
 		>::type
 		div_impl(T const& numer, T const& denom) {
-#if defined(_MSC_VER)
+#if defined(_MSC_VER) && (_MSC_VER > 1900)
 			typename sprout::detail::div_t_traits<T>::type result = {numer / denom, numer % denom};
 			return result;
 #else
diff --git a/sprout/type/string/to_string.hpp b/sprout/type/string/to_string.hpp
index d113aaa7..ade0c80c 100644
--- a/sprout/type/string/to_string.hpp
+++ b/sprout/type/string/to_string.hpp
@@ -23,7 +23,7 @@
 
 namespace sprout {
 	namespace types {
-#ifndef SPROUT_CONFIG_DISABLE_CONSTEXPR
+#if !defined(SPROUT_CONFIG_DISABLE_CONSTEXPR) && !defined(SPROUT_NO_STATIC_CONSTEXPR_INITIALIZATION)
 		//
 		// to_string
 		//