From 2c3d75c7091178056640d914d3efd0518815df92 Mon Sep 17 00:00:00 2001
From: Jinhao <cnjinhao@hotmail.com>
Date: Tue, 25 Sep 2018 02:07:15 +0800
Subject: [PATCH] fix bug of C++ feature detection(#338)

---
 include/nana/c++defines.hpp  | 6 +++---
 source/gui/widgets/label.cpp | 2 +-
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/include/nana/c++defines.hpp b/include/nana/c++defines.hpp
index ef5d8e9f..9456887f 100644
--- a/include/nana/c++defines.hpp
+++ b/include/nana/c++defines.hpp
@@ -211,10 +211,10 @@
 
 
 #undef _nana_std_optional
-#if ((defined(_MSC_VER) && (_MSC_VER >= 1912) && ((!defined(_MSVC_LANG)) || _MSVC_LANG < 201703))) ||	\
-	((__cplusplus < 201703L) || \
+#if ((defined(_MSC_VER) && ((!defined(_MSVC_LANG)) || _MSVC_LANG < 201703))) ||	\
+	((!defined(_MSC_VER)) && ((__cplusplus < 201703L) || \
 		(defined(__clang__) && (__clang_major__ * 100 + __clang_minor__ < 400)) ||				\
-		(!defined(__clang__) && defined(__GNUC__) && (__GNUC__ * 100 + __GNUC_MINOR__ < 701))	\
+		(!defined(__clang__) && defined(__GNUC__) && (__GNUC__ * 100 + __GNUC_MINOR__ < 701)))	\
 	)
 #	define _nana_std_optional
 #endif
diff --git a/source/gui/widgets/label.cpp b/source/gui/widgets/label.cpp
index 03b88215..88fe88f2 100644
--- a/source/gui/widgets/label.cpp
+++ b/source/gui/widgets/label.cpp
@@ -303,7 +303,7 @@ namespace nana
 							extent_size.width = width_px;
 
 						for (auto & vsline : rs.vslines)
-							extent_size.height += vsline.extent_height_px;
+							extent_size.height += static_cast<size::value_type>(vsline.extent_height_px);
 
 						content_lines.emplace_back(std::move(rs.vslines));