diff --git a/include/boost/smart_ptr/detail/yield_k.hpp b/include/boost/smart_ptr/detail/yield_k.hpp
index c3d0450..5beefd6 100644
--- a/include/boost/smart_ptr/detail/yield_k.hpp
+++ b/include/boost/smart_ptr/detail/yield_k.hpp
@@ -27,6 +27,10 @@
 #include <boost/config.hpp>
 #include <boost/predef.h>
 
+#if defined __MINGW32__
+#include <_mingw.h>
+#endif
+
 #if BOOST_PLAT_WINDOWS_RUNTIME
 #include <thread>
 #endif
@@ -60,10 +64,10 @@ namespace detail
 {
 
 #if !defined( BOOST_USE_WINDOWS_H ) && !BOOST_PLAT_WINDOWS_RUNTIME
-#if BOOST_COMP_CLANG
-  extern "C" __declspec(dllimport) void __stdcall Sleep( unsigned long ms );
-#else
+#if !BOOST_COMP_CLANG || (defined __MINGW32__ && !defined __MINGW64_VERSION_MAJOR)
   extern "C" void __stdcall Sleep( unsigned long ms );
+#else
+  extern "C" __declspec(dllimport) void __stdcall Sleep( unsigned long ms );
 #endif
 #endif