diff --git a/src/hb-atomic-private.hh b/src/hb-atomic-private.hh
index 60cbcf91b..2336a9fcb 100644
--- a/src/hb-atomic-private.hh
+++ b/src/hb-atomic-private.hh
@@ -45,6 +45,9 @@
 #elif !defined(HB_NO_MT) && (defined(_WIN32) || defined(__CYGWIN__))
 
 #define WIN32_LEAN_AND_MEAN
+#ifndef _WIN32_WINNT
+#define _WIN32_WINNT 0x0600
+#endif
 #include <windows.h>
 
 /* MinGW has a convoluted history of supporting MemoryBarrier