diff --git a/src/platformsupport/edid/qedidvendortable_p.h b/src/platformsupport/edid/qedidvendortable_p.h
index d09642d649d..948a9cecfcd 100644
--- a/src/platformsupport/edid/qedidvendortable_p.h
+++ b/src/platformsupport/edid/qedidvendortable_p.h
@@ -47,6 +47,15 @@
 #ifndef QEDIDVENDORTABLE_P_H
 #define QEDIDVENDORTABLE_P_H
 
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+
 QT_BEGIN_NAMESPACE
 
 typedef struct VendorTable {
diff --git a/util/edid/qedidvendortable.py b/util/edid/qedidvendortable.py
index 6d30f3a60da..500abf08903 100755
--- a/util/edid/qedidvendortable.py
+++ b/util/edid/qedidvendortable.py
@@ -82,6 +82,15 @@ header = """
 #ifndef QEDIDVENDORTABLE_P_H
 #define QEDIDVENDORTABLE_P_H
 
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+
 QT_BEGIN_NAMESPACE
 
 typedef struct VendorTable {