diff --git a/test/system_error_test.cpp b/test/system_error_test.cpp
index 41f4612..d3dbec6 100644
--- a/test/system_error_test.cpp
+++ b/test/system_error_test.cpp
@@ -22,7 +22,9 @@
 #include <boost/system/system_error.hpp>
 #include <iostream>
 
-#include <winerror.h>
+#ifdef BOOST_WINDOWS_API
+# include <winerror.h>
+#endif
 
 using boost::system::system_error;
 using boost::system::error_code;