diff --git a/src/widgets/accessible/accessible.pri b/src/widgets/accessible/accessible.pri
index bcdfbd639c46d43d049b1ceb74cf78b2859b5cf3..ac8205b1e3a9e352095bcf995a6e55bad1eb34d0 100644
--- a/src/widgets/accessible/accessible.pri
+++ b/src/widgets/accessible/accessible.pri
@@ -4,12 +4,12 @@ contains(QT_CONFIG, accessibility) {
     HEADERS += \
         accessible/qaccessiblewidget.h \
         accessible/qaccessiblewidgetfactory_p.h \
-        accessible/complexwidgets.h \
-        accessible/itemviews.h \
-        accessible/qaccessiblemenu.h \
-        accessible/qaccessiblewidgets.h \
-        accessible/rangecontrols.h \
-        accessible/simplewidgets.h
+        accessible/complexwidgets_p.h \
+        accessible/itemviews_p.h \
+        accessible/qaccessiblemenu_p.h \
+        accessible/qaccessiblewidgets_p.h \
+        accessible/rangecontrols_p.h \
+        accessible/simplewidgets_p.h
 
     SOURCES += \
         accessible/qaccessiblewidget.cpp \
diff --git a/src/widgets/accessible/complexwidgets.cpp b/src/widgets/accessible/complexwidgets.cpp
index 60a1329d5e2a3d32eb2f7d33489274c85fa232aa..6e985c86e8abcda6f27a573604f183dcaa4aa52d 100644
--- a/src/widgets/accessible/complexwidgets.cpp
+++ b/src/widgets/accessible/complexwidgets.cpp
@@ -31,7 +31,7 @@
 **
 ****************************************************************************/
 
-#include "complexwidgets.h"
+#include "complexwidgets_p.h"
 
 #include <qaccessible.h>
 #include <qapplication.h>
diff --git a/src/widgets/accessible/complexwidgets.h b/src/widgets/accessible/complexwidgets_p.h
similarity index 94%
rename from src/widgets/accessible/complexwidgets.h
rename to src/widgets/accessible/complexwidgets_p.h
index bd063e75174833cc674a8452e1571d26b1c89427..8edf996818bb795bfd6f2b96fe1dcd25dfada364 100644
--- a/src/widgets/accessible/complexwidgets.h
+++ b/src/widgets/accessible/complexwidgets_p.h
@@ -34,6 +34,17 @@
 #ifndef COMPLEXWIDGETS_H
 #define COMPLEXWIDGETS_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.
+//
+// We mean it.
+//
+
 #include <QtCore/qpointer.h>
 #include <QtWidgets/qaccessiblewidget.h>
 #include <QtWidgets/qabstractitemview.h>
diff --git a/src/widgets/accessible/itemviews.cpp b/src/widgets/accessible/itemviews.cpp
index 4f6cb56060a19f2261203e47c482a11a79b2968f..6534d51a45e543153f978b15fb5783bdaf7a7c61 100644
--- a/src/widgets/accessible/itemviews.cpp
+++ b/src/widgets/accessible/itemviews.cpp
@@ -31,7 +31,7 @@
 **
 ****************************************************************************/
 
-#include "itemviews.h"
+#include "itemviews_p.h"
 
 #include <qheaderview.h>
 #include <qtableview.h>
diff --git a/src/widgets/accessible/itemviews.h b/src/widgets/accessible/itemviews_p.h
similarity index 97%
rename from src/widgets/accessible/itemviews.h
rename to src/widgets/accessible/itemviews_p.h
index c1bd70a390509ed061dffbccb97ada18084fdcc4..a1b6a6db9fc8fb97f52adc7f95e84a0928c4a9a9 100644
--- a/src/widgets/accessible/itemviews.h
+++ b/src/widgets/accessible/itemviews_p.h
@@ -34,6 +34,17 @@
 #ifndef ACCESSIBLE_ITEMVIEWS_H
 #define ACCESSIBLE_ITEMVIEWS_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.
+//
+// We mean it.
+//
+
 #include "QtCore/qpointer.h"
 #include <QtGui/qaccessible.h>
 #include <QtWidgets/qaccessiblewidget.h>
diff --git a/src/widgets/accessible/qaccessiblemenu.cpp b/src/widgets/accessible/qaccessiblemenu.cpp
index 72eb82b2b7338132db4566e0a4b47609f7c434c5..a0a7852851d50df6cf7dc4898299151cd38a69f9 100644
--- a/src/widgets/accessible/qaccessiblemenu.cpp
+++ b/src/widgets/accessible/qaccessiblemenu.cpp
@@ -31,7 +31,7 @@
 **
 ****************************************************************************/
 
-#include "qaccessiblemenu.h"
+#include "qaccessiblemenu_p.h"
 
 #include <qmenu.h>
 #include <qmenubar.h>
diff --git a/src/widgets/accessible/qaccessiblemenu.h b/src/widgets/accessible/qaccessiblemenu_p.h
similarity index 94%
rename from src/widgets/accessible/qaccessiblemenu.h
rename to src/widgets/accessible/qaccessiblemenu_p.h
index 9c7671072d2a06479d5f36ce89f32d55791230fa..b42c852ff19e8c568843c2456319ce339ad2a8d4 100644
--- a/src/widgets/accessible/qaccessiblemenu.h
+++ b/src/widgets/accessible/qaccessiblemenu_p.h
@@ -34,6 +34,17 @@
 #ifndef QACCESSIBLEMENU_H
 #define QACCESSIBLEMENU_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.
+//
+// We mean it.
+//
+
 #include <QtWidgets/qaccessiblewidget.h>
 #include <QtCore/qpointer.h>
 
diff --git a/src/widgets/accessible/qaccessiblewidgetfactory.cpp b/src/widgets/accessible/qaccessiblewidgetfactory.cpp
index e8b325b93fad8400c0196501b2a20c0061ecae59..4fa7c894826a24bbcde3bb383ee29d1d7eb8d721 100644
--- a/src/widgets/accessible/qaccessiblewidgetfactory.cpp
+++ b/src/widgets/accessible/qaccessiblewidgetfactory.cpp
@@ -31,12 +31,12 @@
 **
 ****************************************************************************/
 
-#include "qaccessiblewidgets.h"
-#include "qaccessiblemenu.h"
-#include "simplewidgets.h"
-#include "rangecontrols.h"
-#include "complexwidgets.h"
-#include "itemviews.h"
+#include "qaccessiblewidgets_p.h"
+#include "qaccessiblemenu_p.h"
+#include "simplewidgets_p.h"
+#include "rangecontrols_p.h"
+#include "complexwidgets_p.h"
+#include "itemviews_p.h"
 
 #include <qpushbutton.h>
 #include <qtoolbutton.h>
diff --git a/src/widgets/accessible/qaccessiblewidgetfactory_p.h b/src/widgets/accessible/qaccessiblewidgetfactory_p.h
index b3f9d8a2511b10ef5e5112876797e09550756ff7..caa37dcf818ef0c3e9f1d277228e86d4f974fc9b 100644
--- a/src/widgets/accessible/qaccessiblewidgetfactory_p.h
+++ b/src/widgets/accessible/qaccessiblewidgetfactory_p.h
@@ -36,6 +36,17 @@
 #ifndef QACCESSIBLEWIDGETFACTORY_H
 #define QACCESSIBLEWIDGETFACTORY_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.
+//
+// We mean it.
+//
+
 QT_BEGIN_NAMESPACE
 
 QAccessibleInterface *qAccessibleFactory(const QString &classname, QObject *object);
diff --git a/src/widgets/accessible/qaccessiblewidgets.cpp b/src/widgets/accessible/qaccessiblewidgets.cpp
index a2bf14b25b6363571e53146687683af1d188065a..604c754ea1b22137328a7926129d547301f57bd1 100644
--- a/src/widgets/accessible/qaccessiblewidgets.cpp
+++ b/src/widgets/accessible/qaccessiblewidgets.cpp
@@ -31,7 +31,7 @@
 **
 ****************************************************************************/
 
-#include "qaccessiblewidgets.h"
+#include "qaccessiblewidgets_p.h"
 #include "qabstracttextdocumentlayout.h"
 #include "qapplication.h"
 #include "qclipboard.h"
diff --git a/src/widgets/accessible/qaccessiblewidgets.h b/src/widgets/accessible/qaccessiblewidgets_p.h
similarity index 97%
rename from src/widgets/accessible/qaccessiblewidgets.h
rename to src/widgets/accessible/qaccessiblewidgets_p.h
index 53f8c2c603504a81bbaeacf307a461e23aecc0a3..4bdc229578b751520db69f1b672b0b6b5770caf7 100644
--- a/src/widgets/accessible/qaccessiblewidgets.h
+++ b/src/widgets/accessible/qaccessiblewidgets_p.h
@@ -34,6 +34,17 @@
 #ifndef QACCESSIBLEWIDGETS_H
 #define QACCESSIBLEWIDGETS_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.
+//
+// We mean it.
+//
+
 #include <QtWidgets/qaccessiblewidget.h>
 
 #ifndef QT_NO_ACCESSIBILITY
diff --git a/src/widgets/accessible/rangecontrols.cpp b/src/widgets/accessible/rangecontrols.cpp
index 002d4a9ef462ec585a60f58784c6a3341439b761..0607a35269584b3d2dd7ec8334af3bf6b28fb85f 100644
--- a/src/widgets/accessible/rangecontrols.cpp
+++ b/src/widgets/accessible/rangecontrols.cpp
@@ -31,7 +31,7 @@
 **
 ****************************************************************************/
 
-#include "rangecontrols.h"
+#include "rangecontrols_p.h"
 
 #include <qslider.h>
 #include <qdial.h>
@@ -47,7 +47,7 @@
 #include <qmath.h>
 #include <private/qmath_p.h>
 
-#include "simplewidgets.h" // let spinbox use line edit's interface
+#include "simplewidgets_p.h" // let spinbox use line edit's interface
 
 QT_BEGIN_NAMESPACE
 
diff --git a/src/widgets/accessible/rangecontrols.h b/src/widgets/accessible/rangecontrols_p.h
similarity index 96%
rename from src/widgets/accessible/rangecontrols.h
rename to src/widgets/accessible/rangecontrols_p.h
index 11d4435e9d276df4727d591e2cfac912a704adf1..32c6d6985fe5980288bdd3d9cd40111036c1be3d 100644
--- a/src/widgets/accessible/rangecontrols.h
+++ b/src/widgets/accessible/rangecontrols_p.h
@@ -34,6 +34,17 @@
 #ifndef RANGECONTROLS_H
 #define RANGECONTROLS_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.
+//
+// We mean it.
+//
+
 #include <QtWidgets/qaccessiblewidget.h>
 
 QT_BEGIN_NAMESPACE
diff --git a/src/widgets/accessible/simplewidgets.cpp b/src/widgets/accessible/simplewidgets.cpp
index b08c21939ae9fc0500566c222ca3f2cbfda8fbbb..065c618cf7ef8fc8c2b7cb0bc885bd08465a9f66 100644
--- a/src/widgets/accessible/simplewidgets.cpp
+++ b/src/widgets/accessible/simplewidgets.cpp
@@ -31,7 +31,7 @@
 **
 ****************************************************************************/
 
-#include "simplewidgets.h"
+#include "simplewidgets_p.h"
 
 #include <qabstractbutton.h>
 #include <qcheckbox.h>
diff --git a/src/widgets/accessible/simplewidgets.h b/src/widgets/accessible/simplewidgets_p.h
similarity index 96%
rename from src/widgets/accessible/simplewidgets.h
rename to src/widgets/accessible/simplewidgets_p.h
index 0dfd9f79c89dc1cb60323cd2566654eab9a99bdd..c2e904273fa47261f1c500147d7be974ef6618ff 100644
--- a/src/widgets/accessible/simplewidgets.h
+++ b/src/widgets/accessible/simplewidgets_p.h
@@ -34,6 +34,17 @@
 #ifndef SIMPLEWIDGETS_H
 #define SIMPLEWIDGETS_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.
+//
+// We mean it.
+//
+
 #include <QtCore/qcoreapplication.h>
 #include <QtWidgets/qaccessiblewidget.h>