diff --git a/include/nana/system/timepiece.hpp b/include/nana/system/timepiece.hpp
index 248a798e..443a4a0e 100644
--- a/include/nana/system/timepiece.hpp
+++ b/include/nana/system/timepiece.hpp
@@ -13,6 +13,8 @@
 #ifndef NANA_SYSTEM_TIMEPIECE_HPP
 #define NANA_SYSTEM_TIMEPIECE_HPP
 
+#include "../c++defines.hpp"
+
 namespace nana
 {
 namespace system