Merge "Merge remote-tracking branch 'origin/5.14' into 5.15"

25 files changed, 300 insertions, 37 deletions

diff --git a/src/corelib/codecs/qutfcodec.cpp b/src/corelib/codecs/qutfcodec.cpp
index af36bd7e2f..8561f908b9 100644
--- a/src/corelib/codecs/qutfcodec.cpp
+++ b/src/corelib/codecs/qutfcodec.cpp
@@ -930,6 +930,7 @@ QString QUtf32::convertToUnicode(const char *chars, int len, QTextCodec::Convert
         tuple[num++] = *chars++;
         if (num == 4) {
             if (!headerdone) {
+                headerdone = true;
                 if (endian == DetectEndianness) {
                     if (tuple[0] == 0xff && tuple[1] == 0xfe && tuple[2] == 0 && tuple[3] == 0 && endian != BigEndianness) {
                         endian = LittleEndianness;
diff --git a/src/corelib/io/qurl.cpp b/src/corelib/io/qurl.cpp
index def4a1095f..104161bc33 100644
--- a/src/corelib/io/qurl.cpp
+++ b/src/corelib/io/qurl.cpp
@@ -4192,7 +4192,7 @@ static bool isIp6(const QString &text)
 
 /*!
     Returns a valid URL from a user supplied \a userInput string if one can be
-    deducted. In the case that is not possible, an invalid QUrl() is returned.
+    deduced. In the case that is not possible, an invalid QUrl() is returned.
 
     This overload takes a \a workingDirectory path, in order to be able to
     handle relative paths. This is especially useful when handling command
diff --git a/src/corelib/itemmodels/qsortfilterproxymodel.cpp b/src/corelib/itemmodels/qsortfilterproxymodel.cpp
index 21303549ab..61d37d5062 100644
--- a/src/corelib/itemmodels/qsortfilterproxymodel.cpp
+++ b/src/corelib/itemmodels/qsortfilterproxymodel.cpp
@@ -3055,12 +3055,8 @@ bool QSortFilterProxyModel::filterAcceptsRow(int source_row, const QModelIndex &
     Returns \c true if the item in the column indicated by the given \a source_column
     and \a source_parent should be included in the model; otherwise returns \c false.
 
-    The default implementation returns \c true if the value held by the relevant item
-    matches the filter string, wildcard string or regular expression.
-
-    \note By default, the Qt::DisplayRole is used to determine if the column
-    should be accepted or not. This can be changed by setting the \l
-    filterRole property.
+    \note The default implementation always returns \c true. You must reimplement this
+    method to get the described behavior.
 
     \sa filterAcceptsRow(), setFilterFixedString(), setFilterRegExp(), setFilterWildcard()
 */
diff --git a/src/corelib/text/qharfbuzz.cpp b/src/corelib/text/qharfbuzz.cpp
index a3e266ccd2..f54ce26206 100644
--- a/src/corelib/text/qharfbuzz.cpp
+++ b/src/corelib/text/qharfbuzz.cpp
@@ -72,7 +72,7 @@ HB_UChar16 HB_GetMirroredChar(HB_UChar16 ch)
 
 void (*HB_Library_Resolve(const char *library, int version, const char *symbol))()
 {
-#if !QT_CONFIG(library)
+#if !QT_CONFIG(library) || defined(Q_OS_WASM)
     Q_UNUSED(library);
     Q_UNUSED(version);
     Q_UNUSED(symbol);
diff --git a/src/corelib/text/qstring.h b/src/corelib/text/qstring.h
index 1f4e856660..61325c7486 100644
--- a/src/corelib/text/qstring.h
+++ b/src/corelib/text/qstring.h
@@ -1124,7 +1124,7 @@ int QStringView::toWCharArray(wchar_t *array) const
     if (sizeof(wchar_t) == sizeof(QChar)) {
         if (auto src = data())
             memcpy(array, src, sizeof(QChar) * size());
-        return size();
+        return int(size());     // ### q6sizetype
     } else {
         return QString::toUcs4_helper(reinterpret_cast<const ushort *>(data()), int(size()),
                                       reinterpret_cast<uint *>(array));
diff --git a/src/corelib/tools/qlinkedlist.h b/src/corelib/tools/qlinkedlist.h
index 64c6b4d326..14fbc34b9d 100644
--- a/src/corelib/tools/qlinkedlist.h
+++ b/src/corelib/tools/qlinkedlist.h
@@ -70,14 +70,14 @@ QT_WARNING_DISABLE_DEPRECATED
 
 QT_BEGIN_NAMESPACE
 
-struct QT_DEPRECATED_VERSION_5_15 Q_CORE_EXPORT QLinkedListData
+struct QT_DEPRECATED_VERSION_5_15 QLinkedListData
 {
     QLinkedListData *n, *p;
     QtPrivate::RefCount ref;
     int size;
     uint sharable : 1;
 
-    static const QLinkedListData shared_null;
+    Q_CORE_EXPORT static const QLinkedListData shared_null;
 };
 
 template <typename T>
diff --git a/src/gui/kernel/qguiapplication.cpp b/src/gui/kernel/qguiapplication.cpp
index bbcb7d9cc5..469563c415 100644
--- a/src/gui/kernel/qguiapplication.cpp
+++ b/src/gui/kernel/qguiapplication.cpp
@@ -610,7 +610,7 @@ static QWindowGeometrySpecification windowGeometrySpecification = Q_WINDOW_GEOME
         \li \c {dialogs=[xp|none]}, \c xp uses XP-style native dialogs and
             \c none disables them.
 
-        \li \c {dpiawareness=[0|1|2} Sets the DPI awareness of the process
+        \li \c {dpiawareness=[0|1|2]} Sets the DPI awareness of the process
                (see \l{High DPI Displays}, since Qt 5.4).
         \li \c {fontengine=freetype}, uses the FreeType font engine.
         \li \c {menus=[native|none]}, controls the use of native menus.
diff --git a/src/gui/painting/qcolor.cpp b/src/gui/painting/qcolor.cpp
index 917706e8cf..f15f6aeebd 100644
--- a/src/gui/painting/qcolor.cpp
+++ b/src/gui/painting/qcolor.cpp
@@ -3264,6 +3264,7 @@ const uint qt_inv_premul_factor[256] = {
 /*!
     \namespace QColorConstants
     \inmodule QtGui
+    \since 5.14
 
     \brief The QColorConstants namespace contains QColor predefined constants.
 
diff --git a/src/gui/util/qshadergraph.cpp b/src/gui/util/qshadergraph.cpp
index b05b710713..46fe6ac6d6 100644
--- a/src/gui/util/qshadergraph.cpp
+++ b/src/gui/util/qshadergraph.cpp
@@ -44,13 +44,20 @@ QT_BEGIN_NAMESPACE
 
 namespace
 {
-    QVector<QShaderNode> copyOutputNodes(const QVector<QShaderNode> &nodes)
+    QVector<QShaderNode> copyOutputNodes(const QVector<QShaderNode> &nodes, const QVector<QShaderGraph::Edge> &edges)
     {
         auto res = QVector<QShaderNode>();
         std::copy_if(nodes.cbegin(), nodes.cend(),
                      std::back_inserter(res),
-                     [] (const QShaderNode &node) {
-                         return node.type() == QShaderNode::Output;
+                     [&edges] (const QShaderNode &node) {
+                         return node.type() == QShaderNode::Output ||
+                                (node.type() == QShaderNode::Function &&
+                                 !std::any_of(edges.cbegin(),
+                                              edges.cend(),
+                                              [&node] (const QShaderGraph::Edge &edge) {
+                                                  return edge.sourceNodeUuid ==
+                                                         node.uuid();
+                                              }));
                      });
         return res;
     }
@@ -210,8 +217,8 @@ QVector<QShaderGraph::Statement> QShaderGraph::createStatements(const QStringLis
 
     auto result = QVector<Statement>();
     QVector<Edge> currentEdges = enabledEdges;
-    QVector<QUuid> currentUuids = [enabledNodes] {
-        const QVector<QShaderNode> inputs = copyOutputNodes(enabledNodes);
+    QVector<QUuid> currentUuids = [enabledNodes, enabledEdges] {
+        const QVector<QShaderNode> inputs = copyOutputNodes(enabledNodes, enabledEdges);
         auto res = QVector<QUuid>();
         std::transform(inputs.cbegin(), inputs.cend(),
                        std::back_inserter(res),
diff --git a/src/network/access/qhttpnetworkconnectionchannel.cpp b/src/network/access/qhttpnetworkconnectionchannel.cpp
index 72af21bd8f..ccdb1cd6cd 100644
--- a/src/network/access/qhttpnetworkconnectionchannel.cpp
+++ b/src/network/access/qhttpnetworkconnectionchannel.cpp
@@ -1099,6 +1099,7 @@ void QHttpNetworkConnectionChannel::_q_error(QAbstractSocket::SocketError socket
 
         if (reply) {
             reply->d_func()->errorString = errorString;
+            reply->d_func()->httpErrorCode = errorCode;
             emit reply->finishedWithError(errorCode, errorString);
             reply = nullptr;
             if (protocolHandler)
diff --git a/src/network/access/qhttpnetworkreply.cpp b/src/network/access/qhttpnetworkreply.cpp
index af456c3607..2024c0fefb 100644
--- a/src/network/access/qhttpnetworkreply.cpp
+++ b/src/network/access/qhttpnetworkreply.cpp
@@ -158,6 +158,11 @@ QString QHttpNetworkReply::errorString() const
     return d_func()->errorString;
 }
 
+QNetworkReply::NetworkError QHttpNetworkReply::errorCode() const
+{
+    return d_func()->httpErrorCode;
+}
+
 QString QHttpNetworkReply::reasonPhrase() const
 {
     return d_func()->reasonPhrase;
diff --git a/src/network/access/qhttpnetworkreply_p.h b/src/network/access/qhttpnetworkreply_p.h
index 12cfe359aa..9c03a403e1 100644
--- a/src/network/access/qhttpnetworkreply_p.h
+++ b/src/network/access/qhttpnetworkreply_p.h
@@ -115,6 +115,8 @@ public:
     QString errorString() const;
     void setErrorString(const QString &error);
 
+    QNetworkReply::NetworkError errorCode() const;
+
     QString reasonPhrase() const;
 
     qint64 bytesAvailable() const;
@@ -259,6 +261,7 @@ public:
     qint64 removedContentLength;
     QPointer<QHttpNetworkConnection> connection;
     QPointer<QHttpNetworkConnectionChannel> connectionChannel;
+    QNetworkReply::NetworkError httpErrorCode = QNetworkReply::NoError;
 
     bool autoDecompress;
 
diff --git a/src/network/access/qhttpthreaddelegate.cpp b/src/network/access/qhttpthreaddelegate.cpp
index 7757fb9503..dcc8c9337e 100644
--- a/src/network/access/qhttpthreaddelegate.cpp
+++ b/src/network/access/qhttpthreaddelegate.cpp
@@ -428,6 +428,12 @@ void QHttpThreadDelegate::startRequest()
 
     connect(httpReply, SIGNAL(cacheCredentials(QHttpNetworkRequest,QAuthenticator*)),
             this, SLOT(cacheCredentialsSlot(QHttpNetworkRequest,QAuthenticator*)));
+    if (httpReply->errorCode() != QNetworkReply::NoError) {
+        if (synchronous)
+            synchronousFinishedWithErrorSlot(httpReply->errorCode(), httpReply->errorString());
+        else
+            finishedWithErrorSlot(httpReply->errorCode(), httpReply->errorString());
+    }
 }
 
 // This gets called from the user thread or by the synchronous HTTP timeout timer
diff --git a/src/network/access/qnetworkaccessmanager.cpp b/src/network/access/qnetworkaccessmanager.cpp
index 1120446bc7..7745f4b752 100644
--- a/src/network/access/qnetworkaccessmanager.cpp
+++ b/src/network/access/qnetworkaccessmanager.cpp
@@ -1477,7 +1477,7 @@ QNetworkReply *QNetworkAccessManager::createRequest(QNetworkAccessManager::Opera
         // immediately set 'networkAccessible' even before we start
         // the monitor.
 #ifdef QT_NO_BEARERMANAGEMENT
-        if (d->networkAccessible
+        if (!d->networkAccessible
 #else
         if (d->networkAccessible == NotAccessible
 #endif // QT_NO_BEARERMANAGEMENT
diff --git a/src/network/kernel/qnetconmonitor_win.cpp b/src/network/kernel/qnetconmonitor_win.cpp
index 1566e7f914..59b6cd5b66 100644
--- a/src/network/kernel/qnetconmonitor_win.cpp
+++ b/src/network/kernel/qnetconmonitor_win.cpp
@@ -163,11 +163,14 @@ private:
     ComPtr<QNetworkConnectionEvents> connectionEvents;
     // We can assume we have access to internet/subnet when this class is created because
     // connection has already been established to the peer:
-    NLM_CONNECTIVITY connectivity =
-            NLM_CONNECTIVITY(NLM_CONNECTIVITY_IPV4_INTERNET | NLM_CONNECTIVITY_IPV6_INTERNET
-                             | NLM_CONNECTIVITY_IPV4_SUBNET | NLM_CONNECTIVITY_IPV6_SUBNET);
+    NLM_CONNECTIVITY connectivity = NLM_CONNECTIVITY(
+            NLM_CONNECTIVITY_IPV4_INTERNET | NLM_CONNECTIVITY_IPV6_INTERNET
+            | NLM_CONNECTIVITY_IPV4_SUBNET | NLM_CONNECTIVITY_IPV6_SUBNET
+            | NLM_CONNECTIVITY_IPV4_LOCALNETWORK | NLM_CONNECTIVITY_IPV6_LOCALNETWORK
+            | NLM_CONNECTIVITY_IPV4_NOTRAFFIC | NLM_CONNECTIVITY_IPV6_NOTRAFFIC);
 
     bool sameSubnet = false;
+    bool isLinkLocal = false;
     bool monitoring = false;
     bool comInitFailed = false;
     bool remoteIsIPv6 = false;
@@ -370,6 +373,7 @@ bool QNetworkConnectionMonitorPrivate::setTargets(const QHostAddress &local,
         return false;
     }
     sameSubnet = remote.isInSubnet(local, it->prefixLength());
+    isLinkLocal = remote.isLinkLocal() && local.isLinkLocal();
     remoteIsIPv6 = remote.protocol() == QAbstractSocket::IPv6Protocol;
 
     return connectionEvents->setTarget(iface);
@@ -461,9 +465,28 @@ void QNetworkConnectionMonitor::stopMonitoring()
 bool QNetworkConnectionMonitor::isReachable()
 {
     Q_D(QNetworkConnectionMonitor);
-    NLM_CONNECTIVITY required = d->sameSubnet
-            ? (d->remoteIsIPv6 ? NLM_CONNECTIVITY_IPV6_SUBNET : NLM_CONNECTIVITY_IPV4_SUBNET)
-            : (d->remoteIsIPv6 ? NLM_CONNECTIVITY_IPV6_INTERNET : NLM_CONNECTIVITY_IPV4_INTERNET);
+
+    const NLM_CONNECTIVITY RequiredSameSubnetIPv6 =
+            NLM_CONNECTIVITY(NLM_CONNECTIVITY_IPV6_SUBNET | NLM_CONNECTIVITY_IPV6_LOCALNETWORK
+                             | NLM_CONNECTIVITY_IPV6_INTERNET);
+    const NLM_CONNECTIVITY RequiredSameSubnetIPv4 =
+            NLM_CONNECTIVITY(NLM_CONNECTIVITY_IPV4_SUBNET | NLM_CONNECTIVITY_IPV4_LOCALNETWORK
+                             | NLM_CONNECTIVITY_IPV4_INTERNET);
+
+    NLM_CONNECTIVITY required;
+    if (d->isLinkLocal) {
+        required = NLM_CONNECTIVITY(
+                d->remoteIsIPv6 ? NLM_CONNECTIVITY_IPV6_NOTRAFFIC | RequiredSameSubnetIPv6
+                                : NLM_CONNECTIVITY_IPV4_NOTRAFFIC | RequiredSameSubnetIPv4);
+    } else if (d->sameSubnet) {
+        required =
+                NLM_CONNECTIVITY(d->remoteIsIPv6 ? RequiredSameSubnetIPv6 : RequiredSameSubnetIPv4);
+
+    } else {
+        required = NLM_CONNECTIVITY(d->remoteIsIPv6 ? NLM_CONNECTIVITY_IPV6_INTERNET
+                                                    : NLM_CONNECTIVITY_IPV4_INTERNET);
+    }
+
     return d_func()->connectivity & required;
 }
 
@@ -695,7 +718,8 @@ bool QNetworkStatusMonitor::isNetworkAccessible()
 {
     return d_func()->connectivity
             & (NLM_CONNECTIVITY_IPV4_INTERNET | NLM_CONNECTIVITY_IPV6_INTERNET
-               | NLM_CONNECTIVITY_IPV4_SUBNET | NLM_CONNECTIVITY_IPV6_SUBNET);
+               | NLM_CONNECTIVITY_IPV4_SUBNET | NLM_CONNECTIVITY_IPV6_SUBNET
+               | NLM_CONNECTIVITY_IPV4_LOCALNETWORK | NLM_CONNECTIVITY_IPV6_LOCALNETWORK);
 }
 
 bool QNetworkStatusMonitor::isEnabled()
diff --git a/src/network/socket/qnativesocketengine_win.cpp b/src/network/socket/qnativesocketengine_win.cpp
index dd115c33dc..2581fc048e 100644
--- a/src/network/socket/qnativesocketengine_win.cpp
+++ b/src/network/socket/qnativesocketengine_win.cpp
@@ -590,7 +590,8 @@ bool QNativeSocketEnginePrivate::fetchConnectionParameters()
     // local address of the socket which bound on both IPv4 and IPv6 interfaces.
     // This address does not match to any special address and should not be used
     // to send the data. So, replace it with QHostAddress::Any.
-    if (socketProtocol == QAbstractSocket::IPv6Protocol) {
+    const uchar ipv6MappedNet[] = {0,0,0,0, 0,0,0,0, 0,0,0xff,0xff, 0,0,0,0};
+    if (localAddress.isInSubnet(QHostAddress(ipv6MappedNet), 128 - 32)) {
         bool ok = false;
         const quint32 localIPv4 = localAddress.toIPv4Address(&ok);
         if (ok && localIPv4 == INADDR_ANY) {
diff --git a/src/platformsupport/windowsuiautomation/uiaserverinterfaces_p.h b/src/platformsupport/windowsuiautomation/uiaserverinterfaces_p.h
index fd39b6ee33..fde16206da 100644
--- a/src/platformsupport/windowsuiautomation/uiaserverinterfaces_p.h
+++ b/src/platformsupport/windowsuiautomation/uiaserverinterfaces_p.h
@@ -383,4 +383,21 @@ __CRT_UUID_DECL(IWindowProvider, 0x987df77b, 0xdb06, 0x4d77, 0x8f,0x8a, 0x86,0xa
 #endif
 #endif
 
+
+#ifndef __IExpandCollapseProvider_INTERFACE_DEFINED__
+#define __IExpandCollapseProvider_INTERFACE_DEFINED__
+DEFINE_GUID(IID_IExpandCollapseProvider, 0xd847d3a5, 0xcab0, 0x4a98, 0x8c,0x32, 0xec,0xb4,0x5c,0x59,0xad,0x24);
+MIDL_INTERFACE("d847d3a5-cab0-4a98-8c32-ecb45c59ad24")
+IExpandCollapseProvider : public IUnknown
+{
+public:
+    virtual HRESULT STDMETHODCALLTYPE Expand() = 0;
+    virtual HRESULT STDMETHODCALLTYPE Collapse() = 0;
+    virtual HRESULT STDMETHODCALLTYPE get_ExpandCollapseState(__RPC__out enum ExpandCollapseState *pRetVal) = 0;
+};
+#ifdef __CRT_UUID_DECL
+__CRT_UUID_DECL(IExpandCollapseProvider, 0xd847d3a5, 0xcab0, 0x4a98, 0x8c,0x32, 0xec,0xb4,0x5c,0x59,0xad,0x24)
+#endif
+#endif
+
 #endif
diff --git a/src/platformsupport/windowsuiautomation/uiatypes_p.h b/src/platformsupport/windowsuiautomation/uiatypes_p.h
index 8ef71843a3..afbc957094 100644
--- a/src/platformsupport/windowsuiautomation/uiatypes_p.h
+++ b/src/platformsupport/windowsuiautomation/uiatypes_p.h
@@ -155,6 +155,13 @@ enum WindowInteractionState {
     WindowInteractionState_NotResponding           = 4
 };
 
+enum ExpandCollapseState {
+    ExpandCollapseState_Collapsed         = 0,
+    ExpandCollapseState_Expanded          = 1,
+    ExpandCollapseState_PartiallyExpanded = 2,
+    ExpandCollapseState_LeafNode          = 3
+};
+
 struct UiaRect {
     double left;
     double top;
diff --git a/src/plugins/platforms/cocoa/qcocoabackingstore.mm b/src/plugins/platforms/cocoa/qcocoabackingstore.mm
index 2e15d11564..cb019c3775 100644
--- a/src/plugins/platforms/cocoa/qcocoabackingstore.mm
+++ b/src/plugins/platforms/cocoa/qcocoabackingstore.mm
@@ -574,7 +574,8 @@ void QCALayerBackingStore::flush(QWindow *flushedWindow, const QRegion &region,
 
         qCInfo(lcQpaBackingStore) << "Flushing" << subImage
             << "to" << flushedView.layer << "of subview" << flushedView;
-        QCFType<CGImageRef> cgImage = subImage.toCGImage();
+        QCFType<CGImageRef> cgImage = CGImageCreateCopyWithColorSpace(
+            QCFType<CGImageRef>(subImage.toCGImage()), colorSpace());
         flushedView.layer.contents = (__bridge id)static_cast<CGImageRef>(cgImage);
     }
 
diff --git a/src/plugins/platforms/windows/uiautomation/qwindowsuiaexpandcollapseprovider.cpp b/src/plugins/platforms/windows/uiautomation/qwindowsuiaexpandcollapseprovider.cpp
new file mode 100644
index 0000000000..6ac8de23fa
--- /dev/null
+++ b/src/plugins/platforms/windows/uiautomation/qwindowsuiaexpandcollapseprovider.cpp
@@ -0,0 +1,120 @@
+/****************************************************************************
+**
+** Copyright (C) 2020 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the plugins of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QtGui/qtguiglobal.h>
+#if QT_CONFIG(accessibility)
+
+#include "qwindowsuiaexpandcollapseprovider.h"
+#include "qwindowsuiautils.h"
+#include "qwindowscontext.h"
+
+#include <QtGui/qaccessible.h>
+#include <QtCore/qloggingcategory.h>
+#include <QtCore/qstring.h>
+
+QT_BEGIN_NAMESPACE
+
+using namespace QWindowsUiAutomation;
+
+
+QWindowsUiaExpandCollapseProvider::QWindowsUiaExpandCollapseProvider(QAccessible::Id id) :
+    QWindowsUiaBaseProvider(id)
+{
+}
+
+QWindowsUiaExpandCollapseProvider::~QWindowsUiaExpandCollapseProvider() = default;
+
+HRESULT STDMETHODCALLTYPE QWindowsUiaExpandCollapseProvider::Expand()
+{
+    qCDebug(lcQpaUiAutomation) << __FUNCTION__;
+
+    QAccessibleInterface *accessible = accessibleInterface();
+    if (!accessible)
+        return UIA_E_ELEMENTNOTAVAILABLE;
+
+    QAccessibleActionInterface *actionInterface = accessible->actionInterface();
+    if (!actionInterface)
+        return UIA_E_ELEMENTNOTAVAILABLE;
+
+    if (accessible->childCount() > 0 && accessible->child(0)->state().invisible)
+        actionInterface->doAction(QAccessibleActionInterface::showMenuAction());
+
+    return S_OK;
+}
+
+HRESULT STDMETHODCALLTYPE QWindowsUiaExpandCollapseProvider::Collapse()
+{
+    qCDebug(lcQpaUiAutomation) << __FUNCTION__;
+
+    QAccessibleInterface *accessible = accessibleInterface();
+    if (!accessible)
+        return UIA_E_ELEMENTNOTAVAILABLE;
+
+    QAccessibleActionInterface *actionInterface = accessible->actionInterface();
+    if (!actionInterface)
+        return UIA_E_ELEMENTNOTAVAILABLE;
+
+    if (accessible->childCount() > 0 && !accessible->child(0)->state().invisible)
+        actionInterface->doAction(QAccessibleActionInterface::showMenuAction());
+
+    return S_OK;
+}
+
+HRESULT STDMETHODCALLTYPE QWindowsUiaExpandCollapseProvider::get_ExpandCollapseState(__RPC__out ExpandCollapseState *pRetVal)
+{
+    qCDebug(lcQpaUiAutomation) << __FUNCTION__;
+
+    if (!pRetVal)
+        return E_INVALIDARG;
+    *pRetVal = ExpandCollapseState_LeafNode;
+
+    QAccessibleInterface *accessible = accessibleInterface();
+    if (!accessible)
+        return UIA_E_ELEMENTNOTAVAILABLE;
+
+    if (accessible->childCount() > 0)
+        *pRetVal = accessible->child(0)->state().invisible ?
+                ExpandCollapseState_Collapsed : ExpandCollapseState_Expanded;
+
+    return S_OK;
+}
+
+QT_END_NAMESPACE
+
+#endif // QT_CONFIG(accessibility)
diff --git a/src/plugins/platforms/windows/uiautomation/qwindowsuiaexpandcollapseprovider.h b/src/plugins/platforms/windows/uiautomation/qwindowsuiaexpandcollapseprovider.h
new file mode 100644
index 0000000000..f5b4c2e78b
--- /dev/null
+++ b/src/plugins/platforms/windows/uiautomation/qwindowsuiaexpandcollapseprovider.h
@@ -0,0 +1,69 @@
+/****************************************************************************
+**
+** Copyright (C) 2020 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the plugins of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QWINDOWSUIAEXPANDCOLLAPSEPROVIDER_H
+#define QWINDOWSUIAEXPANDCOLLAPSEPROVIDER_H
+
+#include <QtGui/qtguiglobal.h>
+#if QT_CONFIG(accessibility)
+
+#include "qwindowsuiabaseprovider.h"
+
+QT_BEGIN_NAMESPACE
+
+// Implements the Expand/Collapse control pattern provider. Used for menu items with submenus.
+class QWindowsUiaExpandCollapseProvider : public QWindowsUiaBaseProvider,
+                                          public QWindowsComBase<IExpandCollapseProvider>
+{
+    Q_DISABLE_COPY_MOVE(QWindowsUiaExpandCollapseProvider)
+public:
+    explicit QWindowsUiaExpandCollapseProvider(QAccessible::Id id);
+    virtual ~QWindowsUiaExpandCollapseProvider() override;
+
+    // IExpandCollapseProvider
+    HRESULT STDMETHODCALLTYPE Expand() override;
+    HRESULT STDMETHODCALLTYPE Collapse() override;
+    HRESULT STDMETHODCALLTYPE get_ExpandCollapseState(__RPC__out ExpandCollapseState *pRetVal) override;
+};
+
+QT_END_NAMESPACE
+
+#endif // QT_CONFIG(accessibility)
+
+#endif // QWINDOWSUIAEXPANDCOLLAPSEPROVIDER_H
diff --git a/src/plugins/platforms/windows/uiautomation/qwindowsuiamainprovider.cpp b/src/plugins/platforms/windows/uiautomation/qwindowsuiamainprovider.cpp
index 93cfd095e4..68881663eb 100644
--- a/src/plugins/platforms/windows/uiautomation/qwindowsuiamainprovider.cpp
+++ b/src/plugins/platforms/windows/uiautomation/qwindowsuiamainprovider.cpp
@@ -53,6 +53,7 @@
 #include "qwindowsuiagridprovider.h"
 #include "qwindowsuiagriditemprovider.h"
 #include "qwindowsuiawindowprovider.h"
+#include "qwindowsuiaexpandcollapseprovider.h"
 #include "qwindowscombase.h"
 #include "qwindowscontext.h"
 #include "qwindowsuiautils.h"
@@ -341,6 +342,14 @@ HRESULT QWindowsUiaMainProvider::GetPatternProvider(PATTERNID idPattern, IUnknow
             *pRetVal = new QWindowsUiaInvokeProvider(id());
         }
         break;
+    case UIA_ExpandCollapsePatternId:
+        // Menu items with submenus.
+        if (accessible->role() == QAccessible::MenuItem
+                && accessible->childCount() > 0
+                && accessible->child(0)->role() == QAccessible::PopupMenu) {
+            *pRetVal = new QWindowsUiaExpandCollapseProvider(id());
+        }
+        break;
     default:
         break;
     }
diff --git a/src/plugins/platforms/windows/uiautomation/uiautomation.pri b/src/plugins/platforms/windows/uiautomation/uiautomation.pri
index ee9332e7ea..1c4b018d1c 100644
--- a/src/plugins/platforms/windows/uiautomation/uiautomation.pri
+++ b/src/plugins/platforms/windows/uiautomation/uiautomation.pri
@@ -19,6 +19,7 @@ SOURCES += \
     $$PWD/qwindowsuiagridprovider.cpp \
     $$PWD/qwindowsuiagriditemprovider.cpp \
     $$PWD/qwindowsuiawindowprovider.cpp \
+    $$PWD/qwindowsuiaexpandcollapseprovider.cpp \
     $$PWD/qwindowsuiautils.cpp
 
 HEADERS += \
@@ -39,6 +40,7 @@ HEADERS += \
     $$PWD/qwindowsuiagridprovider.h \
     $$PWD/qwindowsuiagriditemprovider.h \
     $$PWD/qwindowsuiawindowprovider.h \
+    $$PWD/qwindowsuiaexpandcollapseprovider.h \
     $$PWD/qwindowsuiautils.h
 
 mingw: QMAKE_USE *= uuid
diff --git a/src/plugins/platforms/xcb/qxcbscreen.cpp b/src/plugins/platforms/xcb/qxcbscreen.cpp
index 698be45aa8..505f7343ce 100644
--- a/src/plugins/platforms/xcb/qxcbscreen.cpp
+++ b/src/plugins/platforms/xcb/qxcbscreen.cpp
@@ -665,7 +665,9 @@ QImage::Format QXcbScreen::format() const
     bool needsRgbSwap;
     qt_xcb_imageFormatForVisual(connection(), screen()->root_depth, visualForId(screen()->root_visual), &format, &needsRgbSwap);
     // We are ignoring needsRgbSwap here and just assumes the backing-store will handle it.
-    return format;
+    if (format != QImage::Format_Invalid)
+        return format;
+    return QImage::Format_RGB32;
 }
 
 int QXcbScreen::forcedDpi() const
diff --git a/src/widgets/itemviews/qabstractitemview.cpp b/src/widgets/itemviews/qabstractitemview.cpp
index 2524d4acfa..5b92fc6790 100644
--- a/src/widgets/itemviews/qabstractitemview.cpp
+++ b/src/widgets/itemviews/qabstractitemview.cpp
@@ -705,15 +705,6 @@ void QAbstractItemView::setModel(QAbstractItemModel *model)
     }
     d->model = (model ? model : QAbstractItemModelPrivate::staticEmptyModel());
 
-    // These asserts do basic sanity checking of the model
-    Q_ASSERT_X(d->model->index(0,0) == d->model->index(0,0),
-               "QAbstractItemView::setModel",
-               "A model should return the exact same index "
-               "(including its internal id/pointer) when asked for it twice in a row.");
-    Q_ASSERT_X(!d->model->index(0,0).parent().isValid(),
-               "QAbstractItemView::setModel",
-               "The parent of a top level index should be invalid");
-
     if (d->model != QAbstractItemModelPrivate::staticEmptyModel()) {
         connect(d->model, SIGNAL(destroyed()),
                 this, SLOT(_q_modelDestroyed()));