--- a/src/java.prefs/windows/native/libprefs/WindowsPreferences.c	Fri Jun 08 11:30:10 2018 +0200
+++ b/src/java.prefs/windows/native/libprefs/WindowsPreferences.c	Fri Jun 08 18:11:32 2018 +0200
@@ -28,6 +28,8 @@
 #include "jni.h"
 #include "jni_util.h"
 #include "jvm.h"
+#include "java_util_prefs_WindowsPreferences.h"
+
 #ifdef __cplusplus
 extern "C" {
 #endif