diff --git a/include/boost/smart_ptr/detail/yield_k.hpp b/include/boost/smart_ptr/detail/yield_k.hpp
index e32d5aa..403f32f 100644
--- a/include/boost/smart_ptr/detail/yield_k.hpp
+++ b/include/boost/smart_ptr/detail/yield_k.hpp
@@ -68,20 +68,15 @@ namespace detail
 # define BOOST_SP_STDCALL __stdcall
 #endif
 
-#if !BOOST_COMP_CLANG || !defined __MINGW32__
-  extern "C" void BOOST_SP_STDCALL Sleep( unsigned long ms );
-#else
-#include <_mingw.h>
-#if !defined __MINGW64_VERSION_MAJOR
-  extern "C" void BOOST_SP_STDCALL Sleep( unsigned long ms );
+#if defined(__LP64__) // Cygwin 64
+  extern "C" __declspec(dllimport) void BOOST_SP_STDCALL Sleep( unsigned int ms );
 #else
   extern "C" __declspec(dllimport) void BOOST_SP_STDCALL Sleep( unsigned long ms );
 #endif
-#endif
 
 #undef BOOST_SP_STDCALL
 
-#endif
+#endif // !defined( BOOST_USE_WINDOWS_H ) && !BOOST_PLAT_WINDOWS_RUNTIME
 
 inline void yield( unsigned k )
 {
diff --git a/test/Jamfile b/test/Jamfile
index c9c7b67..6cff91a 100644
--- a/test/Jamfile
+++ b/test/Jamfile
@@ -272,3 +272,7 @@ run lsp_convertible_test2.cpp ;
 run make_shared_array_tmp_test.cpp ;
 
 run lw_thread_test.cpp : : : <threading>multi ;
+
+compile sp_windows_h_test.cpp ;
+compile spinlock_windows_h_test.cpp ;
+compile yield_k_windows_h_test.cpp ;
diff --git a/test/sp_windows_h_test.cpp b/test/sp_windows_h_test.cpp
new file mode 100644
index 0000000..b4df132
--- /dev/null
+++ b/test/sp_windows_h_test.cpp
@@ -0,0 +1,11 @@
+// Copyright 2018 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+
+#if defined(_WIN32) || defined(__WIN32__) || defined(__CYGWIN__)
+# include <windows.h>
+# include <boost/shared_ptr.hpp>
+#endif
+
+int main()
+{
+}
diff --git a/test/spinlock_windows_h_test.cpp b/test/spinlock_windows_h_test.cpp
new file mode 100644
index 0000000..68a8781
--- /dev/null
+++ b/test/spinlock_windows_h_test.cpp
@@ -0,0 +1,11 @@
+// Copyright 2018 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+
+#if defined(_WIN32) || defined(__WIN32__) || defined(__CYGWIN__)
+# include <windows.h>
+# include <boost/smart_ptr/detail/spinlock.hpp>
+#endif
+
+int main()
+{
+}
diff --git a/test/yield_k_windows_h_test.cpp b/test/yield_k_windows_h_test.cpp
new file mode 100644
index 0000000..c2f88b8
--- /dev/null
+++ b/test/yield_k_windows_h_test.cpp
@@ -0,0 +1,11 @@
+// Copyright 2018 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+
+#if defined(_WIN32) || defined(__WIN32__) || defined(__CYGWIN__)
+# include <windows.h>
+# include <boost/smart_ptr/detail/yield_k.hpp>
+#endif
+
+int main()
+{
+}