Merge remote-tracking branch 'origin/5.7' into 5.8

Conflicts:
	examples/quick/quickwidgets/quickwidget/main.cpp
	src/qml/jsruntime/qv4jsonobject.cpp
	src/qml/jsruntime/qv4qobjectwrapper.cpp
	src/qml/jsruntime/qv4qobjectwrapper_p.h
	src/qml/qml/qqmlengine.cpp
	src/qml/qml/qqmlpropertycache.cpp
	src/qml/qml/qqmlpropertycache_p.h
	src/quick/items/qquickanimatedsprite.cpp
	src/quick/items/qquickitem.cpp
	src/quick/items/qquickitem.h
	src/quick/items/qquickitem_p.h
	src/quick/items/qquickview_p.h
	src/quick/scenegraph/qsgcontext.cpp
	src/quick/scenegraph/qsgdefaultrendercontext.cpp

Change-Id: I172c6fbff97208f21ed4c8b6db3d1747a889f22b

18 files changed, 94 insertions, 103 deletions

diff --git a/src/quick/items/context2d/qquickcontext2dtexture.cpp b/src/quick/items/context2d/qquickcontext2dtexture.cpp
index ddecf7c3d4..4435c0c37b 100644
--- a/src/quick/items/context2d/qquickcontext2dtexture.cpp
+++ b/src/quick/items/context2d/qquickcontext2dtexture.cpp
@@ -548,6 +548,9 @@ QPaintDevice* QQuickContext2DFBOTexture::beginPainting()
 {
     QQuickContext2DTexture::beginPainting();
 
+    const qreal devicePixelRatio = (m_item && m_item->window()) ?
+        m_item->window()->effectiveDevicePixelRatio() : qApp->devicePixelRatio();
+
     if (m_canvasWindow.size().isEmpty()) {
         delete m_fbo;
         delete m_multisampledFbo;
@@ -562,7 +565,7 @@ QPaintDevice* QQuickContext2DFBOTexture::beginPainting()
         delete m_paint_device;
         m_paint_device = 0;
 
-        m_fboSize = npotAdjustedSize(m_canvasWindow.size());
+        m_fboSize = npotAdjustedSize(m_canvasWindow.size() * devicePixelRatio);
         m_canvasWindowChanged = false;
 
         if (doMultisampling()) {
@@ -600,6 +603,7 @@ QPaintDevice* QQuickContext2DFBOTexture::beginPainting()
         QOpenGLPaintDevice *gl_device = new QOpenGLPaintDevice(m_fbo->size());
         gl_device->setPaintFlipped(true);
         gl_device->setSize(m_fbo->size());
+        gl_device->setDevicePixelRatio(devicePixelRatio);
         m_paint_device = gl_device;
     }
 
@@ -705,8 +709,12 @@ QPaintDevice* QQuickContext2DImageTexture::beginPainting()
     if (m_canvasWindow.size().isEmpty())
         return 0;
 
+    const qreal devicePixelRatio = (m_item && m_item->window()) ?
+        m_item->window()->effectiveDevicePixelRatio() : qApp->devicePixelRatio();
+
     if (m_canvasWindowChanged) {
-        m_image = QImage(m_canvasWindow.size(), QImage::Format_ARGB32_Premultiplied);
+        m_image = QImage(m_canvasWindow.size() * devicePixelRatio, QImage::Format_ARGB32_Premultiplied);
+        m_image.setDevicePixelRatio(devicePixelRatio);
         m_image.fill(0x00000000);
         m_canvasWindowChanged = false;
     }
diff --git a/src/quick/items/qquickanimatedsprite.cpp b/src/quick/items/qquickanimatedsprite.cpp
index 991ca8519f..8aeef4ef4a 100644
--- a/src/quick/items/qquickanimatedsprite.cpp
+++ b/src/quick/items/qquickanimatedsprite.cpp
@@ -42,6 +42,7 @@
 #include "qquicksprite_p.h"
 #include "qquickspriteengine_p.h"
 #include <QtQuick/private/qsgcontext_p.h>
+#include <QtQuick/private/qquickitem_p.h>
 #include <private/qsgadaptationlayer_p.h>
 #include <private/qqmlglobal_p.h>
 #include <QtQuick/qsgnode.h>
@@ -349,7 +350,7 @@ void QQuickAnimatedSprite::start()
     }
     emit currentFrameChanged(0);
     emit runningChanged(true);
-    update();
+    maybeUpdate();
 }
 
 void QQuickAnimatedSprite::stop()
@@ -360,7 +361,7 @@ void QQuickAnimatedSprite::stop()
         return;
     d->m_pauseOffset = 0;
     emit runningChanged(false);
-    update();
+    maybeUpdate();
 }
 
 /*!
@@ -379,7 +380,15 @@ void QQuickAnimatedSprite::advance(int frames)
         d->m_curFrame += d->m_spriteEngine->maxFrames();
     d->m_curFrame = d->m_curFrame % d->m_spriteEngine->maxFrames();
     emit currentFrameChanged(d->m_curFrame);
-    update();
+    maybeUpdate();
+}
+
+void QQuickAnimatedSprite::maybeUpdate()
+{
+    QQuickItemPrivate *priv = QQuickItemPrivate::get(this);
+    const QLazilyAllocated<QQuickItemPrivate::ExtraData> &extraData = priv->extra;
+    if ((extraData.isAllocated() && extraData->effectRefCount > 0) || priv->effectiveVisible)
+        update();
 }
 
 /*!
@@ -399,7 +408,7 @@ void QQuickAnimatedSprite::pause()
     d->m_pauseOffset = d->m_timestamp.elapsed();
     d->m_paused = true;
     emit pausedChanged(true);
-    update();
+    maybeUpdate();
 }
 
 /*!
@@ -419,7 +428,7 @@ void QQuickAnimatedSprite::resume()
     d->m_pauseOffset = d->m_pauseOffset - d->m_timestamp.elapsed();
     d->m_paused = false;
     emit pausedChanged(false);
-    update();
+    maybeUpdate();
 }
 
 void QQuickAnimatedSprite::setRunning(bool arg)
@@ -610,7 +619,6 @@ void QQuickAnimatedSprite::createEngine()
     d->m_spriteEngine = new QQuickSpriteEngine(QList<QQuickSprite*>(spriteList), this);
     d->m_spriteEngine->startAssemblingImage();
     reset();
-    update();
 }
 
 QSGSpriteNode* QQuickAnimatedSprite::initNode()
@@ -622,10 +630,10 @@ QSGSpriteNode* QQuickAnimatedSprite::initNode()
         return nullptr;
     } else if (d->m_spriteEngine->status() == QQuickPixmap::Null) {
         d->m_spriteEngine->startAssemblingImage();
-        update();//Schedule another update, where we will check again
+        maybeUpdate();//Schedule another update, where we will check again
         return nullptr;
     } else if (d->m_spriteEngine->status() == QQuickPixmap::Loading) {
-        update();//Schedule another update, where we will check again
+        maybeUpdate();//Schedule another update, where we will check again
         return nullptr;
     }
 
@@ -651,7 +659,7 @@ void QQuickAnimatedSprite::reset()
 {
     Q_D(QQuickAnimatedSprite);
     d->m_pleaseReset = true;
-    update();
+    maybeUpdate();
 }
 
 QSGNode *QQuickAnimatedSprite::updatePaintNode(QSGNode *oldNode, UpdatePaintNodeData *)
@@ -673,7 +681,7 @@ QSGNode *QQuickAnimatedSprite::updatePaintNode(QSGNode *oldNode, UpdatePaintNode
         prepareNextFrame(node);
 
     if (d->m_running && !d->m_paused)
-        update();
+        maybeUpdate();
 
     return node;
 }
@@ -726,7 +734,7 @@ void QQuickAnimatedSprite::prepareNextFrame(QSGSpriteNode *node)
             frameAt = 0;
             d->m_running = false;
             emit runningChanged(false);
-            update();
+            maybeUpdate();
         }
     } else {
         frameAt = d->m_curFrame;
@@ -734,7 +742,7 @@ void QQuickAnimatedSprite::prepareNextFrame(QSGSpriteNode *node)
     if (d->m_curFrame != lastFrame) {
         if (isCurrentFrameChangedConnected())
             emit currentFrameChanged(d->m_curFrame);
-        update();
+        maybeUpdate();
     }
 
     qreal frameCount = d->m_spriteEngine->spriteFrames();
diff --git a/src/quick/items/qquickanimatedsprite_p.h b/src/quick/items/qquickanimatedsprite_p.h
index cbd6524c40..564c402fbb 100644
--- a/src/quick/items/qquickanimatedsprite_p.h
+++ b/src/quick/items/qquickanimatedsprite_p.h
@@ -168,6 +168,7 @@ protected:
     void componentComplete() Q_DECL_OVERRIDE;
     QSGNode *updatePaintNode(QSGNode *, UpdatePaintNodeData *) Q_DECL_OVERRIDE;
 private:
+    void maybeUpdate();
     bool isCurrentFrameChangedConnected();
     void prepareNextFrame(QSGSpriteNode *node);
     void reloadImage();
diff --git a/src/quick/items/qquickflickable.cpp b/src/quick/items/qquickflickable.cpp
index e69c6a8d59..12b01b8aaf 100644
--- a/src/quick/items/qquickflickable.cpp
+++ b/src/quick/items/qquickflickable.cpp
@@ -1556,11 +1556,11 @@ void QQuickFlickablePrivate::replayDelayedPress()
 
         // If we have the grab, release before delivering the event
         if (QQuickWindow *w = q->window()) {
+            replayingPressEvent = true;
             if (w->mouseGrabberItem() == q)
                 q->ungrabMouse();
 
             // Use the event handler that will take care of finding the proper item to propagate the event
-            replayingPressEvent = true;
             QCoreApplication::sendEvent(w, mouseEvent.data());
             replayingPressEvent = false;
         }
@@ -1590,7 +1590,7 @@ void QQuickFlickable::timerEvent(QTimerEvent *event)
         d->movementEndingTimer.stop();
         d->pressed = false;
         d->stealMouse = false;
-        if (!d->velocityTimeline.isActive())
+        if (!d->velocityTimeline.isActive() && !d->timeline.isActive())
             movementEnding(true, true);
     }
 }
@@ -1643,7 +1643,7 @@ void QQuickFlickable::viewportMoved(Qt::Orientations orient)
 void QQuickFlickablePrivate::viewportAxisMoved(AxisData &data, qreal minExtent, qreal maxExtent, qreal vSize,
                                            QQuickTimeLineCallback::Callback fixupCallback)
 {
-    if (pressed || calcVelocity) {
+    if (!scrollingPhase && (pressed || calcVelocity)) {
         int elapsed = data.velocityTime.restart();
         if (elapsed > 0) {
             qreal velocity = (data.lastPos - data.move.value()) * 1000 / elapsed;
@@ -2216,7 +2216,8 @@ void QQuickFlickable::mouseUngrabEvent()
     Q_D(QQuickFlickable);
     // if our mouse grab has been removed (probably by another Flickable),
     // fix our state
-    d->cancelInteraction();
+    if (!d->replayingPressEvent)
+        d->cancelInteraction();
 }
 
 void QQuickFlickablePrivate::cancelInteraction()
diff --git a/src/quick/items/qquickitem.cpp b/src/quick/items/qquickitem.cpp
index eaf26a5c9a..814a73d9a4 100644
--- a/src/quick/items/qquickitem.cpp
+++ b/src/quick/items/qquickitem.cpp
@@ -7023,15 +7023,6 @@ void QQuickItemPrivate::setHasHoverInChild(bool hasHover)
     }
 }
 
-void QQuickItemPrivate::markObjects(QV4::ExecutionEngine *e)
-{
-    Q_Q(QQuickItem);
-    QV4::QObjectWrapper::markWrapper(q, e);
-
-    for (QQuickItem *child : qAsConst(childItems))
-        QQuickItemPrivate::get(child)->markObjects(e);
-}
-
 #ifndef QT_NO_CURSOR
 
 /*!
@@ -8195,6 +8186,37 @@ QAccessible::Role QQuickItemPrivate::accessibleRole() const
 }
 #endif
 
+// helper code to let a visual parent mark its visual children for the garbage collector
+
+namespace QV4 {
+namespace Heap {
+struct QQuickItemWrapper : public QObjectWrapper {
+};
+}
+}
+
+struct QQuickItemWrapper : public QV4::QObjectWrapper {
+    V4_OBJECT2(QQuickItemWrapper, QV4::QObjectWrapper)
+    static void markObjects(QV4::Heap::Base *that, QV4::ExecutionEngine *e);
+};
+
+DEFINE_OBJECT_VTABLE(QQuickItemWrapper);
+
+void QQuickItemWrapper::markObjects(QV4::Heap::Base *that, QV4::ExecutionEngine *e)
+{
+    QObjectWrapper::Data *This = static_cast<QObjectWrapper::Data *>(that);
+    if (QQuickItem *item = static_cast<QQuickItem*>(This->object())) {
+        foreach (QQuickItem *child, QQuickItemPrivate::get(item)->childItems)
+            QV4::QObjectWrapper::markWrapper(child, e);
+    }
+    QV4::QObjectWrapper::markObjects(that, e);
+}
+
+quint64 QQuickItemPrivate::_q_createJSWrapper(QV4::ExecutionEngine *engine)
+{
+    return (engine->memoryManager->allocObject<QQuickItemWrapper>(q_func()))->asReturnedValue();
+}
+
 QT_END_NAMESPACE
 
 #include <moc_qquickitem.cpp>
diff --git a/src/quick/items/qquickitem.h b/src/quick/items/qquickitem.h
index 87ae83246c..510d46739a 100644
--- a/src/quick/items/qquickitem.h
+++ b/src/quick/items/qquickitem.h
@@ -148,6 +148,7 @@ class Q_QUICK_EXPORT QQuickItem : public QObject, public QQmlParserStatus
     Q_PRIVATE_PROPERTY(QQuickItem::d_func(), QQuickItemLayer *layer READ layer DESIGNABLE false CONSTANT FINAL)
 
     Q_CLASSINFO("DefaultProperty", "data")
+    Q_CLASSINFO("qt_QmlJSWrapperFactoryMethod", "_q_createJSWrapper(QV4::ExecutionEngine*)")
 
 public:
     enum Flag {
@@ -442,6 +443,7 @@ protected:
 
 private:
     Q_PRIVATE_SLOT(d_func(), void _q_resourceObjectDeleted(QObject *))
+    Q_PRIVATE_SLOT(d_func(), quint64 _q_createJSWrapper(QV4::ExecutionEngine *))
 
     friend class QQuickWindow;
     friend class QQuickWindowPrivate;
diff --git a/src/quick/items/qquickitem_p.h b/src/quick/items/qquickitem_p.h
index d1511285a9..49a674f2c6 100644
--- a/src/quick/items/qquickitem_p.h
+++ b/src/quick/items/qquickitem_p.h
@@ -300,6 +300,7 @@ public:
 
     void _q_resourceObjectDeleted(QObject *);
     void _q_windowChanged(QQuickWindow *w);
+    quint64 _q_createJSWrapper(QV4::ExecutionEngine *engine);
 
     enum ChangeType {
         Geometry = 0x01,
@@ -593,9 +594,6 @@ public:
     void setHasCursorInChild(bool hasCursor);
     void setHasHoverInChild(bool hasHover);
 
-    // recursive helper to let a visual parent mark its visual children
-    void markObjects(QV4::ExecutionEngine *e);
-
     virtual void updatePolish() { }
 };
 
diff --git a/src/quick/items/qquickmousearea.cpp b/src/quick/items/qquickmousearea.cpp
index 0118d882af..10e6afad33 100644
--- a/src/quick/items/qquickmousearea.cpp
+++ b/src/quick/items/qquickmousearea.cpp
@@ -672,6 +672,7 @@ void QQuickMouseArea::mousePressEvent(QMouseEvent *event)
     Q_D(QQuickMouseArea);
     d->moved = false;
     d->stealMouse = d->preventStealing;
+    d->overThreshold = false;
     if (!d->enabled || !(event->button() & acceptedMouseButtons())) {
         QQuickItem::mousePressEvent(event);
     } else {
@@ -957,6 +958,7 @@ bool QQuickMouseArea::sendMouseEvent(QMouseEvent *event)
             if (!d->pressed) {
                 // no other buttons are pressed
                 d->stealMouse = false;
+                d->overThreshold = false;
                 if (c && c->mouseGrabberItem() == this)
                     ungrabMouse();
                 emit canceled();
diff --git a/src/quick/items/qquickpositioners.cpp b/src/quick/items/qquickpositioners.cpp
index 38e89e78eb..e22427ca49 100644
--- a/src/quick/items/qquickpositioners.cpp
+++ b/src/quick/items/qquickpositioners.cpp
@@ -872,7 +872,7 @@ void QQuickPositionerAttached::setIsLastItem(bool isLastItem)
     the item that is being added. See the \l ViewTransition documentation for more details
     and examples on using these transitions.
 
-    \note This transition is not applied to the items that already part of the positioner
+    \note This transition is not applied to the items that are already part of the positioner
     at the time of its creation. In this case, the \l populate transition is applied instead.
 
     \sa populate, ViewTransition, {Qt Quick Examples - Positioners}
@@ -1039,7 +1039,7 @@ void QQuickColumn::reportConflictingAnchors()
     the item that is being added. See the \l ViewTransition documentation for more details
     and examples on using these transitions.
 
-    \note This transition is not applied to the items that already part of the positioner
+    \note This transition is not applied to the items that are already part of the positioner
     at the time of its creation. In this case, the \l populate transition is applied instead.
 
     \sa populate, ViewTransition, {Qt Quick Examples - Positioners}
@@ -1307,7 +1307,7 @@ void QQuickRow::reportConflictingAnchors()
     the item that is being added. See the \l ViewTransition documentation for more details
     and examples on using these transitions.
 
-    \note This transition is not applied to the items that already part of the positioner
+    \note This transition is not applied to the items that are already part of the positioner
     at the time of its creation. In this case, the \l populate transition is applied instead.
 
     \sa populate, ViewTransition, {Qt Quick Examples - Positioners}
@@ -1882,7 +1882,7 @@ void QQuickGrid::reportConflictingAnchors()
     the item that is being added. See the \l ViewTransition documentation for more details
     and examples on using these transitions.
 
-    \note This transition is not applied to the items that already part of the positioner
+    \note This transition is not applied to the items that are already part of the positioner
     at the time of its creation. In this case, the \l populate transition is applied instead.
 
     \sa populate, ViewTransition, {Qt Quick Examples - Positioners}
diff --git a/src/quick/items/qquickrectangle.cpp b/src/quick/items/qquickrectangle.cpp
index 9e747f2c47..7ba2421d62 100644
--- a/src/quick/items/qquickrectangle.cpp
+++ b/src/quick/items/qquickrectangle.cpp
@@ -365,7 +365,7 @@ QQuickPen *QQuickRectangle::border()
     The gradient to use to fill the rectangle.
 
     This property allows for the construction of simple vertical gradients.
-    Other gradients may by formed by adding rotation to the rectangle.
+    Other gradients may be formed by adding rotation to the rectangle.
 
     \div {class="float-left"}
     \inlineimage declarative-rect_gradient.png
diff --git a/src/quick/items/qquicktext.cpp b/src/quick/items/qquicktext.cpp
index 14268b472e..2bfb4501fc 100644
--- a/src/quick/items/qquicktext.cpp
+++ b/src/quick/items/qquicktext.cpp
@@ -898,11 +898,11 @@ QRectF QQuickTextPrivate::setupTextLayout(qreal *const baseline)
 
             // If the width of the item has changed and it's possible the result of wrapping,
             // eliding, scaling has changed, or the text is not left aligned do another layout.
-            if ((lineWidth < qMin(oldWidth, naturalWidth) || (widthExceeded && lineWidth > oldWidth))
+            if ((!qFuzzyCompare(lineWidth, oldWidth) || (widthExceeded && lineWidth > oldWidth))
                     && (singlelineElide || multilineElide || canWrap || horizontalFit
                         || q->effectiveHAlign() != QQuickText::AlignLeft)) {
                 widthChanged = true;
-                widthExceeded = false;
+                widthExceeded = lineWidth >= qMin(oldWidth, naturalWidth);
                 heightExceeded = false;
                 continue;
             }
@@ -937,7 +937,7 @@ QRectF QQuickTextPrivate::setupTextLayout(qreal *const baseline)
 
             bool wasInLayout = internalWidthUpdate;
             internalWidthUpdate = true;
-            q->setImplicitHeight(naturalHeight);
+            q->setImplicitHeight(naturalHeight + q->topPadding() + q->bottomPadding());
             internalWidthUpdate = wasInLayout;
 
             multilineElide = elideMode == QQuickText::ElideRight
diff --git a/src/quick/items/qquickview.cpp b/src/quick/items/qquickview.cpp
index d79d8ba3cd..a167f01484 100644
--- a/src/quick/items/qquickview.cpp
+++ b/src/quick/items/qquickview.cpp
@@ -48,29 +48,11 @@
 
 #include <QtQml/qqmlengine.h>
 #include <private/qqmlengine_p.h>
+#include <private/qv4qobjectwrapper_p.h>
 #include <QtCore/qbasictimer.h>
 
 QT_BEGIN_NAMESPACE
 
-DEFINE_OBJECT_VTABLE(QV4::QQuickRootItemMarker);
-
-QV4::Heap::QQuickRootItemMarker *QV4::QQuickRootItemMarker::create(QQmlEngine *engine, QQuickWindow *window)
-{
-    QV4::ExecutionEngine *e = QQmlEnginePrivate::getV4Engine(engine);
-    return e->memoryManager->allocObject<QQuickRootItemMarker>(window);
-}
-
-void QV4::QQuickRootItemMarker::markObjects(QV4::Heap::Base *that, QV4::ExecutionEngine *e)
-{
-    QQuickItem *root = static_cast<QQuickRootItemMarker::Data *>(that)->window->contentItem();
-    if (root) {
-        QQuickItemPrivate *rootPrivate = QQuickItemPrivate::get(root);
-        rootPrivate->markObjects(e);
-    }
-
-    QV4::Object::markObjects(that, e);
-}
-
 void QQuickViewPrivate::init(QQmlEngine* e)
 {
     Q_Q(QQuickView);
@@ -84,10 +66,10 @@ void QQuickViewPrivate::init(QQmlEngine* e)
         engine.data()->setIncubationController(q->incubationController());
 
     {
+        // The content item has CppOwnership policy (set in QQuickWindow). Ensure the presence of a JS
+        // wrapper so that the garbage collector can see the policy.
         QV4::ExecutionEngine *v4 = QQmlEnginePrivate::getV4Engine(engine.data());
-        QV4::Scope scope(v4);
-        QV4::Scoped<QV4::QQuickRootItemMarker> v(scope, QV4::QQuickRootItemMarker::create(engine.data(), q));
-        rootItemMarker.set(v4, v);
+        QV4::QObjectWrapper::wrap(v4, contentItem);
     }
 }
 
diff --git a/src/quick/items/qquickview_p.h b/src/quick/items/qquickview_p.h
index 9c0d87984f..a090bdc9f7 100644
--- a/src/quick/items/qquickview_p.h
+++ b/src/quick/items/qquickview_p.h
@@ -108,38 +108,8 @@ public:
     QQuickView::ResizeMode resizeMode;
     QSize initialSize;
     QElapsedTimer frameTimer;
-    QV4::PersistentValue rootItemMarker;
 };
 
-namespace QV4 {
-namespace Heap {
-
-struct QQuickRootItemMarker : Object {
-    inline void init(QQuickWindow *window)
-    {
-        Object::init();
-        this->window = window;
-    }
-
-    QQuickWindow *window;
-};
-
-}
-
-struct QQuickRootItemMarker : public Object
-{
-    V4_OBJECT2(QQuickRootItemMarker, Object)
-
-    static Heap::QQuickRootItemMarker *create(QQmlEngine *engine, QQuickWindow *window);
-
-    static void markObjects(QV4::Heap::Base *that, QV4::ExecutionEngine *e);
-
-};
-
-
-
-}
-
 QT_END_NAMESPACE
 
 #endif // QQUICKVIEW_P_H
diff --git a/src/quick/items/qquickwindowmodule.cpp b/src/quick/items/qquickwindowmodule.cpp
index c624d162a9..deb44ce34d 100644
--- a/src/quick/items/qquickwindowmodule.cpp
+++ b/src/quick/items/qquickwindowmodule.cpp
@@ -47,6 +47,7 @@
 
 #include <private/qguiapplication_p.h>
 #include <private/qqmlengine_p.h>
+#include <private/qv4qobjectwrapper_p.h>
 #include <qpa/qplatformintegration.h>
 
 QT_BEGIN_NAMESPACE
@@ -104,12 +105,11 @@ void QQuickWindowQmlImpl::classBegin()
         if (e && !e->incubationController())
             e->setIncubationController(incubationController());
     }
-    Q_ASSERT(e);
     {
+        // The content item has CppOwnership policy (set in QQuickWindow). Ensure the presence of a JS
+        // wrapper so that the garbage collector can see the policy.
         QV4::ExecutionEngine *v4 = QQmlEnginePrivate::getV4Engine(e);
-        QV4::Scope scope(v4);
-        QV4::ScopedObject v(scope, QV4::QQuickRootItemMarker::create(e, this));
-        d->rootItemMarker = v;
+        QV4::QObjectWrapper::wrap(v4, d->contentItem);
     }
 }
 
diff --git a/src/quick/scenegraph/qsgcontext.cpp b/src/quick/scenegraph/qsgcontext.cpp
index 688fc7db08..d52f69c7a3 100644
--- a/src/quick/scenegraph/qsgcontext.cpp
+++ b/src/quick/scenegraph/qsgcontext.cpp
@@ -307,10 +307,6 @@ QAnimationDriver *QSGContext::createAnimationDriver(QObject *parent)
 
 QSize QSGContext::minimumFBOSize() const
 {
-#ifdef Q_OS_MAC
-    if (QSysInfo::MacintoshVersion < QSysInfo::MV_10_8)
-        return QSize(33, 33);
-#endif
     return QSize(1, 1);
 }
 
diff --git a/src/quick/scenegraph/qsgdefaultrendercontext.cpp b/src/quick/scenegraph/qsgdefaultrendercontext.cpp
index 6f10611ba3..1a17453baf 100644
--- a/src/quick/scenegraph/qsgdefaultrendercontext.cpp
+++ b/src/quick/scenegraph/qsgdefaultrendercontext.cpp
@@ -99,12 +99,12 @@ void QSGDefaultRenderContext::initialize(void *context)
 
 #ifdef Q_OS_LINUX
     const char *vendor = (const char *) funcs->glGetString(GL_VENDOR);
-    if (strstr(vendor, "nouveau"))
+    if (vendor && strstr(vendor, "nouveau"))
         m_brokenIBOs = true;
     const char *renderer = (const char *) funcs->glGetString(GL_RENDERER);
-    if (strstr(renderer, "llvmpipe"))
+    if (renderer && strstr(renderer, "llvmpipe"))
         m_serializedRender = true;
-    if (strstr(vendor, "Hisilicon Technologies") && strstr(renderer, "Immersion.16"))
+    if (vendor && renderer && strstr(vendor, "Hisilicon Technologies") && strstr(renderer, "Immersion.16"))
         m_brokenIBOs = true;
 #endif
 
diff --git a/src/quick/util/qquickimageprovider.cpp b/src/quick/util/qquickimageprovider.cpp
index 6cecf6f6f6..0c245d2b23 100644
--- a/src/quick/util/qquickimageprovider.cpp
+++ b/src/quick/util/qquickimageprovider.cpp
@@ -105,7 +105,7 @@ QImage QQuickTextureFactory::image() const
 }
 
 /*!
-    Returns a QQuickTextureFactory holding the given image.
+    Returns a QQuickTextureFactory holding the given \a image.
 
     This is typically used as a helper in QQuickImageResponse::textureFactory.
 
@@ -187,6 +187,8 @@ QString QQuickImageResponse::errorString() const
     This method is used to communicate that the response is no longer required by the engine.
 
     It may be reimplemented to cancel a request in the provider side, however, it is not mandatory.
+
+    A cancelled QQuickImageResponse still needs to emit finished().
 */
 void QQuickImageResponse::cancel()
 {
diff --git a/src/quick/util/qquickpixmapcache.cpp b/src/quick/util/qquickpixmapcache.cpp
index 9722bf544b..d151c43f7a 100644
--- a/src/quick/util/qquickpixmapcache.cpp
+++ b/src/quick/util/qquickpixmapcache.cpp
@@ -614,7 +614,6 @@ void QQuickPixmapReader::processJobs()
                     if (asyncResponse) {
                         asyncResponses.remove(asyncResponse);
                         asyncResponse->cancel();
-                        asyncResponse->deleteLater();
                     }
                 }
                 PIXMAP_PROFILE(pixmapStateChanged<QQuickProfiler::PixmapLoadingError>(job->url));