Avoid initializing QFlags with 0 or nullptr in further cases

Amends qtbase/af2daafde72db02454d24b7d691aa6861525ab99.
Where applicable, port over to member initialization, thus also
fixing nullptr warnings.

Change-Id: Iaaf2dbbbcf2952253390b8839fd15a1b17be32c0
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>

src/gui/kernel/qguiapplication.cpp

@@ -1763,7 +1763,7 @@ Qt::KeyboardModifiers QGuiApplication::keyboardModifiers()
 */
 Qt::KeyboardModifiers QGuiApplication::queryKeyboardModifiers()
 {
-    CHECK_QAPP_INSTANCE(Qt::KeyboardModifiers(0))
+    CHECK_QAPP_INSTANCE(Qt::KeyboardModifiers{})
     QPlatformIntegration *pi = QGuiApplicationPrivate::platformIntegration();
     return pi->queryKeyboardModifiers();
 }

src/gui/kernel/qplatformdialoghelper.cpp

@@ -186,7 +186,7 @@ QVariant  QPlatformDialogHelper::defaultStyleHint(QPlatformDialogHelper::StyleHi
 class QFontDialogOptionsPrivate : public QSharedData
 {
 public:
-    QFontDialogOptionsPrivate() : options(0) {}
+    QFontDialogOptionsPrivate() = default;
 
     QFontDialogOptions::FontDialogOptions options;
     QString windowTitle;
@@ -328,7 +328,7 @@ Q_GLOBAL_STATIC(QColorDialogStaticData, qColorDialogStaticData)
 class QColorDialogOptionsPrivate : public QSharedData
 {
 public:
-    QColorDialogOptionsPrivate() : options(0) {}
+    QColorDialogOptionsPrivate() = default;
     // Write out settings around destruction of dialogs
     ~QColorDialogOptionsPrivate() { qColorDialogStaticData()->writeSettings(); }
 
@@ -465,24 +465,16 @@ void QPlatformColorDialogHelper::setOptions(const QSharedPointer<QColorDialogOpt
 class QFileDialogOptionsPrivate : public QSharedData
 {
 public:
-    QFileDialogOptionsPrivate() : options(0),
-        viewMode(QFileDialogOptions::Detail),
-        fileMode(QFileDialogOptions::AnyFile),
-        acceptMode(QFileDialogOptions::AcceptOpen),
-        filters(QDir::AllEntries | QDir::NoDotAndDotDot | QDir::AllDirs),
-        useDefaultNameFilters(true)
-    {}
-
     QFileDialogOptions::FileDialogOptions options;
     QString windowTitle;
 
-    QFileDialogOptions::ViewMode viewMode;
+    QFileDialogOptions::ViewMode viewMode = QFileDialogOptions::Detail;
-    QFileDialogOptions::FileMode fileMode;
+    QFileDialogOptions::FileMode fileMode = QFileDialogOptions::AnyFile;
-    QFileDialogOptions::AcceptMode acceptMode;
+    QFileDialogOptions::AcceptMode acceptMode = QFileDialogOptions::AcceptOpen;
     QString labels[QFileDialogOptions::DialogLabelCount];
-    QDir::Filters filters;
+    QDir::Filters filters = QDir::AllEntries | QDir::NoDotAndDotDot | QDir::AllDirs;
     QList<QUrl> sidebarUrls;
-    bool useDefaultNameFilters;
+    bool useDefaultNameFilters = true;
     QStringList nameFilters;
     QStringList mimeTypeFilters;
     QString defaultSuffix;

src/gui/painting/qpainter.cpp

@@ -7786,16 +7786,9 @@ QPainterState::QPainterState(const QPainterState *s)
 }
 
 QPainterState::QPainterState()
-    : brushOrigin(0, 0), bgBrush(Qt::white), clipOperation(Qt::NoClip),
+    : brushOrigin(0, 0), WxF(false), VxF(false), clipEnabled(true),
-      renderHints(0),
+      layoutDirection(QGuiApplication::layoutDirection())
-      wx(0), wy(0), ww(0), wh(0), vx(0), vy(0), vw(0), vh(0),
-      opacity(1), WxF(false), VxF(false), clipEnabled(true),
-      bgMode(Qt::TransparentMode), painter(0),
-      layoutDirection(QGuiApplication::layoutDirection()),
-      composition_mode(QPainter::CompositionMode_SourceOver),
-      emulationSpecifier(0), changeFlags(0)
 {
-    dirtyFlags = { };
 }
 
 QPainterState::~QPainterState()

src/gui/painting/qpainter_p.h

@@ -154,29 +154,29 @@ public:
     QFont deviceFont;
     QPen pen;
     QBrush brush;
-    QBrush bgBrush;             // background brush
+    QBrush bgBrush = Qt::white; // background brush
     QRegion clipRegion;
     QPainterPath clipPath;
-    Qt::ClipOperation clipOperation;
+    Qt::ClipOperation clipOperation = Qt::NoClip;
     QPainter::RenderHints renderHints;
     QVector<QPainterClipInfo> clipInfo; // ### Make me smaller and faster to copy around...
     QTransform worldMatrix;       // World transformation matrix, not window and viewport
     QTransform matrix;            // Complete transformation matrix,
     QTransform redirectionMatrix;
-    int wx, wy, ww, wh;         // window rectangle
+    int wx = 0, wy = 0, ww = 0, wh = 0; // window rectangle
-    int vx, vy, vw, vh;         // viewport rectangle
+    int vx = 0, vy = 0, vw = 0, vh = 0; // viewport rectangle
-    qreal opacity;
+    qreal opacity = 1;
 
     uint WxF:1;                 // World transformation
     uint VxF:1;                 // View transformation
     uint clipEnabled:1;
 
-    Qt::BGMode bgMode;
+    Qt::BGMode bgMode = Qt::TransparentMode;
-    QPainter *painter;
+    QPainter *painter = nullptr;
     Qt::LayoutDirection layoutDirection;
-    QPainter::CompositionMode composition_mode;
+    QPainter::CompositionMode composition_mode = QPainter::CompositionMode_SourceOver;
-    uint emulationSpecifier;
+    uint emulationSpecifier = 0;
-    uint changeFlags;
+    uint changeFlags = 0;
 };
 
 struct QPainterDummyState

src/gui/painting/qpainterpath.cpp

@@ -1253,7 +1253,7 @@ void QPainterPath::addText(const QPointF &point, const QFont &f, const QString &
             fe->addOutlineToPath(x, y, glyphs, this,
                                  si.analysis.bidiLevel % 2
                                  ? QTextItem::RenderFlags(QTextItem::RightToLeft)
-                                 : QTextItem::RenderFlags(0));
+                                 : QTextItem::RenderFlags{});
 
             const qreal lw = fe->lineThickness().toReal();
             if (f.d->underline) {

src/gui/text/qfontengine.cpp

@@ -141,7 +141,7 @@ static void hb_getAdvances(HB_Font font, const HB_Glyph *glyphs, hb_uint32 numGl
     qglyphs.glyphs = const_cast<glyph_t *>(glyphs);
     qglyphs.advances = reinterpret_cast<QFixed *>(advances);
 
-    fe->recalcAdvances(&qglyphs, (flags & HB_ShaperFlag_UseDesignMetrics) ? QFontEngine::DesignMetrics : QFontEngine::ShaperFlags(0));
+    fe->recalcAdvances(&qglyphs, (flags & HB_ShaperFlag_UseDesignMetrics) ? QFontEngine::DesignMetrics : QFontEngine::ShaperFlags{});
 }
 
 static HB_Bool hb_canRender(HB_Font font, const HB_UChar16 *string, hb_uint32 length)

src/gui/text/qtextengine.cpp

@@ -1896,7 +1896,7 @@ int QTextEngine::shapeTextWithHarfbuzz(const QScriptItem &si, const ushort *stri
         }
 
         if (kerningEnabled && !shaper_item.kerning_applied)
-            actualFontEngine->doKerning(&g, option.useDesignMetrics() ? QFontEngine::DesignMetrics : QFontEngine::ShaperFlags(0));
+            actualFontEngine->doKerning(&g, option.useDesignMetrics() ? QFontEngine::DesignMetrics : QFontEngine::ShaperFlags{});
 
         if (engineIdx != 0) {
             for (quint32 i = 0; i < shaper_item.num_glyphs; ++i)
@@ -3895,12 +3895,7 @@ QStackTextEngine::QStackTextEngine(const QString &string, const QFont &f)
 }
 
 QTextItemInt::QTextItemInt(const QScriptItem &si, QFont *font, const QTextCharFormat &format)
-    : justified(false),
+    : charFormat(format),
-      underlineStyle(QTextCharFormat::NoUnderline),
-      charFormat(format),
-      num_chars(0),
-      chars(nullptr),
-      logClusters(nullptr),
       f(font),
       fontEngine(font->d->engineForScript(si.analysis.script))
 {
@@ -3910,13 +3905,9 @@ QTextItemInt::QTextItemInt(const QScriptItem &si, QFont *font, const QTextCharFo
 }
 
 QTextItemInt::QTextItemInt(const QGlyphLayout &g, QFont *font, const QChar *chars_, int numChars, QFontEngine *fe, const QTextCharFormat &format)
-    : flags(0),
+    : charFormat(format),
-      justified(false),
-      underlineStyle(QTextCharFormat::NoUnderline),
-      charFormat(format),
       num_chars(numChars),
       chars(chars_),
-      logClusters(nullptr),
       f(font),
       glyphs(g),
       fontEngine(fe)

src/gui/text/qtextengine_p.h

@@ -303,10 +303,7 @@ struct QScriptItem;
 class QTextItemInt : public QTextItem
 {
 public:
-    inline QTextItemInt()
+    inline QTextItemInt() = default;
-        : justified(false), underlineStyle(QTextCharFormat::NoUnderline), num_chars(0), chars(nullptr),
-          logClusters(nullptr), f(nullptr), fontEngine(nullptr)
-    {}
     QTextItemInt(const QScriptItem &si, QFont *font, const QTextCharFormat &format = QTextCharFormat());
     QTextItemInt(const QGlyphLayout &g, QFont *font, const QChar *chars, int numChars, QFontEngine *fe,
                  const QTextCharFormat &format = QTextCharFormat());
@@ -321,16 +318,16 @@ public:
     QFixed width;
 
     RenderFlags flags;
-    bool justified;
+    bool justified = false;
-    QTextCharFormat::UnderlineStyle underlineStyle;
+    QTextCharFormat::UnderlineStyle underlineStyle = QTextCharFormat::NoUnderline;
     const QTextCharFormat charFormat;
-    int num_chars;
+    int num_chars = 0;
-    const QChar *chars;
+    const QChar *chars = nullptr;
-    const unsigned short *logClusters;
+    const unsigned short *logClusters = nullptr;
-    const QFont *f;
+    const QFont *f = nullptr;
 
     QGlyphLayout glyphs;
-    QFontEngine *fontEngine;
+    QFontEngine *fontEngine = nullptr;
 };
 
 struct QScriptItem

src/gui/vulkan/qvulkaninstance.cpp

@@ -251,7 +251,6 @@ public:
     QVulkanInstancePrivate(QVulkanInstance *q)
         : q_ptr(q),
           vkInst(VK_NULL_HANDLE),
-          flags(0),
           errorCode(VK_SUCCESS)
     { }
     ~QVulkanInstancePrivate() { reset(); }

src/network/bearer/qnetworkconfigmanager.cpp

@@ -355,7 +355,7 @@ QNetworkConfigurationManager::Capabilities QNetworkConfigurationManager::capabil
     if (priv)
         return priv->capabilities();
 
-    return QNetworkConfigurationManager::Capabilities(0);
+    return {};
 }
 
 /*!

src/network/kernel/qnetworkinterface.cpp

@@ -746,7 +746,7 @@ QString QNetworkInterface::humanReadableName() const
 */
 QNetworkInterface::InterfaceFlags QNetworkInterface::flags() const
 {
-    return d ? d->flags : InterfaceFlags(0);
+    return d ? d->flags : InterfaceFlags{};
 }
 
 /*!

src/network/socket/qlocalsocket_unix.cpp

@@ -64,7 +64,6 @@ QLocalSocketPrivate::QLocalSocketPrivate() : QIODevicePrivate(),
         delayConnect(0),
         connectTimer(0),
         connectingSocket(-1),
-        connectingOpenMode(0),
         state(QLocalSocket::UnconnectedState)
 {
 }

src/opengl/qgl.cpp

@@ -83,7 +83,8 @@ QT_BEGIN_NAMESPACE
 class QGLDefaultExtensions
 {
 public:
-    QGLDefaultExtensions() : extensions(0) {
+    QGLDefaultExtensions()
+    {
         QGLTemporaryContext tempContext;
         Q_ASSERT(QOpenGLContext::currentContext());
         QOpenGLExtensions *ext = qgl_extensions();

src/platformsupport/eventdispatchers/qwindowsguieventdispatcher.cpp

@@ -61,7 +61,7 @@ QT_BEGIN_NAMESPACE
 */
 
 QWindowsGuiEventDispatcher::QWindowsGuiEventDispatcher(QObject *parent) :
-    QEventDispatcherWin32(parent), m_flags(0)
+    QEventDispatcherWin32(parent)
 {
     setObjectName(QStringLiteral("QWindowsGuiEventDispatcher"));
     createInternalHwnd(); // QTBUG-40881: Do not delay registering timers, etc. for QtMfc.

src/platformsupport/fontdatabases/windows/qwindowsfontenginedirectwrite.cpp

@@ -458,7 +458,7 @@ bool QWindowsFontEngineDirectWrite::stringToCMap(const QChar *str, int len, QGly
     glyphs->numGlyphs = actualLength;
 
     if (!(flags & GlyphIndicesOnly))
-        recalcAdvances(glyphs, 0);
+        recalcAdvances(glyphs, {});
 
     return true;
 }

src/platformsupport/input/evdevmouse/qevdevmousehandler.cpp

@@ -99,8 +99,7 @@ std::unique_ptr<QEvdevMouseHandler> QEvdevMouseHandler::create(const QString &de
 }
 
 QEvdevMouseHandler::QEvdevMouseHandler(const QString &device, int fd, bool abs, bool compression, int jitterLimit)
-    : m_device(device), m_fd(fd), m_notify(0), m_x(0), m_y(0), m_prevx(0), m_prevy(0),
+    : m_device(device), m_fd(fd), m_abs(abs), m_compression(compression)
-      m_abs(abs), m_compression(compression), m_buttons(0), m_prevInvalid(true)
 {
     setObjectName(QLatin1String("Evdev Mouse Handler"));
 

src/platformsupport/input/evdevmouse/qevdevmousehandler_p.h

@@ -84,16 +84,16 @@ private:
 
     QString m_device;
     int m_fd;
-    QSocketNotifier *m_notify;
+    QSocketNotifier *m_notify = nullptr;
-    int m_x, m_y;
+    int m_x = 0, m_y = 0;
-    int m_prevx, m_prevy;
+    int m_prevx = 0, m_prevy = 0;
     bool m_abs;
     bool m_compression;
     Qt::MouseButtons m_buttons;
     Qt::MouseButton m_button;
     QEvent::Type m_eventType;
     int m_jitterLimitSquared;
-    bool m_prevInvalid;
+    bool m_prevInvalid = true;
     int m_hardwareWidth;
     int m_hardwareHeight;
     qreal m_hardwareScalerY;

src/platformsupport/input/evdevtouch/qevdevtouchhandler.cpp

@@ -113,16 +113,13 @@ public:
     QList<QWindowSystemInterface::TouchPoint> m_lastTouchPoints;
 
     struct Contact {
-        int trackingId;
+        int trackingId = -1;
-        int x;
+        int x = 0;
-        int y;
+        int y = 0;
-        int maj;
+        int maj = -1;
-        int pressure;
+        int pressure = 0;
-        Qt::TouchPointState state;
+        Qt::TouchPointState state = Qt::TouchPointPressed;
         QTouchEvent::TouchPoint::InfoFlags flags;
-        Contact() : trackingId(-1),
-            x(0), y(0), maj(-1), pressure(0),
-            state(Qt::TouchPointPressed), flags(0) { }
     };
     QHash<int, Contact> m_contacts; // The key is a tracking id for type A, slot number for type B.
     QHash<int, Contact> m_lastContacts;

src/plugins/platforms/windows/qwindowsglcontext.h

@@ -89,7 +89,7 @@ struct QWindowsOpenGLContextFormat
 
     QSurfaceFormat::OpenGLContextProfile profile = QSurfaceFormat::NoProfile;
     int version = 0; //! majorVersion<<8 + minorVersion
-    QSurfaceFormat::FormatOptions options = nullptr;
+    QSurfaceFormat::FormatOptions options;
 };
 
 #ifndef QT_NO_DEBUG_STREAM

src/plugins/platforms/windows/qwindowskeymapper.cpp

@@ -1019,14 +1019,14 @@ bool QWindowsKeyMapper::translateKeyEventInternal(QWindow *window, MSG msg,
                 if (dirStatus == VK_LSHIFT
                         && ((msg.wParam == VK_SHIFT && GetKeyState(VK_LCONTROL))
                             || (msg.wParam == VK_CONTROL && GetKeyState(VK_LSHIFT)))) {
-                    sendExtendedPressRelease(receiver, Qt::Key_Direction_L, nullptr,
+                    sendExtendedPressRelease(receiver, Qt::Key_Direction_L, {},
                                              scancode, vk_key, nModifiers, QString(), false);
                     result = true;
                     dirStatus = 0;
                 } else if (dirStatus == VK_RSHIFT
                            && ( (msg.wParam == VK_SHIFT && GetKeyState(VK_RCONTROL))
                                 || (msg.wParam == VK_CONTROL && GetKeyState(VK_RSHIFT)))) {
-                    sendExtendedPressRelease(receiver, Qt::Key_Direction_R, nullptr,
+                    sendExtendedPressRelease(receiver, Qt::Key_Direction_R, {},
                                              scancode, vk_key, nModifiers, QString(), false);
                     result = true;
                     dirStatus = 0;

src/plugins/platforms/windows/qwindowsmousehandler.cpp

@@ -165,7 +165,7 @@ void QWindowsMouseHandler::clearEvents()
 
 Qt::MouseButtons QWindowsMouseHandler::queryMouseButtons()
 {
-    Qt::MouseButtons result = nullptr;
+    Qt::MouseButtons result;
     const bool mouseSwapped = GetSystemMetrics(SM_SWAPBUTTON);
     if (GetAsyncKeyState(VK_LBUTTON) < 0)
         result |= mouseSwapped ? Qt::RightButton: Qt::LeftButton;
@@ -630,7 +630,7 @@ bool QWindowsMouseHandler::translateTouchEvent(QWindow *window, HWND,
 
     QTouchPointList touchPoints;
     touchPoints.reserve(winTouchPointCount);
-    Qt::TouchPointStates allStates = nullptr;
+    Qt::TouchPointStates allStates;
 
     GetTouchInputInfo(reinterpret_cast<HTOUCHINPUT>(msg.lParam),
                       UINT(msg.wParam), winTouchInputs.data(), sizeof(TOUCHINPUT));

src/plugins/platforms/windows/qwindowspointerhandler.cpp

@@ -482,7 +482,7 @@ bool QWindowsPointerHandler::translateTouchEvent(QWindow *window, HWND hwnd,
                 << " message=" << Qt::hex << msg.message
                 << " count=" << Qt::dec << count;
 
-    Qt::TouchPointStates allStates = nullptr;
+    Qt::TouchPointStates allStates;
 
     for (quint32 i = 0; i < count; ++i) {
         if (QWindowsContext::verbose > 1)

src/plugins/platforms/windows/qwindowstheme.h

@@ -71,7 +71,7 @@ public:
 
     QPixmap standardPixmap(StandardPixmap sp, const QSizeF &size) const override;
 
-    QIcon fileIcon(const QFileInfo &fileInfo, QPlatformTheme::IconOptions iconOptions = nullptr) const override;
+    QIcon fileIcon(const QFileInfo &fileInfo, QPlatformTheme::IconOptions iconOptions = {}) const override;
 
     void windowsThemeChanged(QWindow *window);
     void displayChanged() { refreshIconPixmapSizes(); }

src/plugins/platforms/xcb/qxcbwindow.cpp

@@ -876,7 +876,7 @@ enum {
 
 QXcbWindow::NetWmStates QXcbWindow::netWmStates()
 {
-    NetWmStates result(0);
+    NetWmStates result;
 
     auto reply = Q_XCB_REPLY_UNCHECKED(xcb_get_property, xcb_connection(),
                                        0, m_window, atom(QXcbAtom::_NET_WM_STATE),
@@ -1063,7 +1063,7 @@ void QXcbWindow::setNetWmStateOnUnmappedWindow()
     if (Q_UNLIKELY(m_mapped))
         qCWarning(lcQpaXcb()) << "internal error: " << Q_FUNC_INFO << "called on mapped window";
 
-    NetWmStates states(0);
+    NetWmStates states;
     const Qt::WindowFlags flags = window()->flags();
     if (flags & Qt::WindowStaysOnTopHint) {
         states |= NetWmStateAbove;
@@ -1477,7 +1477,7 @@ uint QXcbWindow::visualIdStatic(QWindow *window)
 
 QXcbWindowFunctions::WmWindowTypes QXcbWindow::wmWindowTypes() const
 {
-    QXcbWindowFunctions::WmWindowTypes result(0);
+    QXcbWindowFunctions::WmWindowTypes result;
 
     auto reply = Q_XCB_REPLY_UNCHECKED(xcb_get_property, xcb_connection(),
                                        0, m_window, atom(QXcbAtom::_NET_WM_WINDOW_TYPE),

src/widgets/graphicsview/qgraphicssceneevent.cpp

@@ -344,8 +344,7 @@ class QGraphicsSceneMouseEventPrivate : public QGraphicsSceneEventPrivate
     Q_DECLARE_PUBLIC(QGraphicsSceneMouseEvent)
 public:
     inline QGraphicsSceneMouseEventPrivate()
-        : button(Qt::NoButton),
+        : button(Qt::NoButton), source(Qt::MouseEventNotSynthesized)
-          buttons(0), modifiers(0), source(Qt::MouseEventNotSynthesized), flags(0)
     { }
 
     QPointF pos;
@@ -691,17 +690,15 @@ class QGraphicsSceneWheelEventPrivate : public QGraphicsSceneEventPrivate
 {
     Q_DECLARE_PUBLIC(QGraphicsSceneWheelEvent)
 public:
-    inline QGraphicsSceneWheelEventPrivate()
+    inline QGraphicsSceneWheelEventPrivate() = default;
-        : buttons(0), modifiers(0), delta(0), orientation(Qt::Horizontal)
-    { }
 
     QPointF pos;
     QPointF scenePos;
     QPoint screenPos;
     Qt::MouseButtons buttons;
     Qt::KeyboardModifiers modifiers;
-    int delta;
+    int delta = 0;
-    Qt::Orientation orientation;
+    Qt::Orientation orientation = Qt::Horizontal;
 };
 
 /*!
@@ -872,15 +869,13 @@ class QGraphicsSceneContextMenuEventPrivate : public QGraphicsSceneEventPrivate
 {
     Q_DECLARE_PUBLIC(QGraphicsSceneContextMenuEvent)
         public:
-    inline QGraphicsSceneContextMenuEventPrivate()
+    inline QGraphicsSceneContextMenuEventPrivate() = default;
-        : modifiers(0), reason(QGraphicsSceneContextMenuEvent::Other)
-        { }
 
     QPointF pos;
     QPointF scenePos;
     QPoint screenPos;
     Qt::KeyboardModifiers modifiers;
-    QGraphicsSceneContextMenuEvent::Reason reason;
+    QGraphicsSceneContextMenuEvent::Reason reason = QGraphicsSceneContextMenuEvent::Other;
 };
 
 /*!

src/widgets/graphicsview/qgraphicsview.cpp

@@ -352,14 +352,13 @@ QGraphicsViewPrivate::QGraphicsViewPrivate()
       alignment(Qt::AlignCenter),
       transformationAnchor(QGraphicsView::AnchorViewCenter), resizeAnchor(QGraphicsView::NoAnchor),
       viewportUpdateMode(QGraphicsView::MinimalViewportUpdate),
-      optimizationFlags(0),
       scene(0),
 #if QT_CONFIG(rubberband)
       rubberBanding(false),
       rubberBandSelectionMode(Qt::IntersectsItemShape),
       rubberBandSelectionOperation(Qt::ReplaceSelection),
 #endif
-      handScrollMotions(0), cacheMode(0),
+      handScrollMotions(0),
 #ifndef QT_NO_CURSOR
       hasStoredOriginalCursor(false),
 #endif

src/widgets/kernel/qboxlayout.cpp

@@ -1173,7 +1173,7 @@ void QBoxLayout::setDirection(Direction direction)
             if (box->magic) {
                 QSpacerItem *sp = box->item->spacerItem();
                 if (sp) {
-                    if (sp->expandingDirections() == Qt::Orientations(0) /*No Direction*/) {
+                    if (sp->expandingDirections() == Qt::Orientations{} /*No Direction*/) {
                         //spacing or strut
                         QSize s = sp->sizeHint();
                         sp->changeSize(s.height(), s.width(),

src/widgets/kernel/qformlayout.cpp

@@ -199,18 +199,17 @@ public:
     ItemMatrix m_matrix;
     QList<QFormLayoutItem *> m_things;
 
-    int layoutWidth;    // the last width that we called setupVerticalLayoutData on (for vLayouts)
+    int layoutWidth = -1;    // the last width that we called setupVerticalLayoutData on (for vLayouts)
 
-    int hfw_width;  // the last width we calculated HFW for
+    int hfw_width = -1;  // the last width we calculated HFW for
-    int hfw_height; // what that height was
+    int hfw_height = -1; // what that height was
-    int hfw_minheight;  // what that minheight was
 
-    int hfw_sh_height;  // the hfw for sh_width
+    int hfw_sh_height = -1;  // the hfw for sh_width
-    int hfw_sh_minheight;   // the minhfw for sh_width
+    int hfw_sh_minheight = -1; // the minhfw for sh_width
 
-    int min_width;  // the width that gets turned into minSize (from updateSizes)
+    int min_width = -1;  // the width that gets turned into minSize (from updateSizes)
-    int sh_width;   // the width that gets turned into prefSize (from updateSizes)
+    int sh_width = -1;   // the width that gets turned into prefSize (from updateSizes)
-    int thresh_width; // the width that we start splitting label/field pairs at (from updateSizes)
+    int thresh_width = QLAYOUTSIZE_MAX; // the width that we start splitting label/field pairs at (from updateSizes)
     QSize minSize;
     QSize prefSize;
     int formMaxWidth;
@@ -222,17 +221,15 @@ public:
 
     QVector<QLayoutStruct> hfwLayouts;
 
-    int hSpacing;
+    int hSpacing = -1;
-    int vSpacing;
+    int vSpacing = -1;
     QLayoutItem* replaceAt(int index, QLayoutItem*) override;
 };
 
 QFormLayoutPrivate::QFormLayoutPrivate()
     : fieldGrowthPolicy(DefaultFieldGrowthPolicy),
       rowWrapPolicy(DefaultRowWrapPolicy), has_hfw(false), dirty(true), sizesDirty(true),
-      expandVertical(0), expandHorizontal(0), labelAlignment(0), formAlignment(0),
+      expandVertical(0), expandHorizontal(0)
-      layoutWidth(-1), hfw_width(-1), hfw_sh_height(-1), min_width(-1),
-      sh_width(-1), thresh_width(QLAYOUTSIZE_MAX), hSpacing(-1), vSpacing(-1)
 {
 }
 
@@ -481,7 +478,6 @@ void QFormLayoutPrivate::recalcHFW(int w)
     } else {
         hfw_width = w;
         hfw_height = qMin(QLAYOUTSIZE_MAX, h);
-        hfw_minheight = qMin(QLAYOUTSIZE_MAX, mh);
     }
 }
 

src/widgets/kernel/qlayoutitem.cpp

@@ -591,7 +591,7 @@ Qt::Orientations QSpacerItem::expandingDirections() const
 Qt::Orientations QWidgetItem::expandingDirections() const
 {
     if (isEmpty())
-        return Qt::Orientations(0);
+        return {};
 
     Qt::Orientations e = wid->sizePolicy().expandingDirections();
     /*

src/widgets/styles/qstyleoption.cpp

@@ -2909,7 +2909,7 @@ QStyleOptionRubberBand::QStyleOptionRubberBand(int version)
 */
 
 QStyleOptionTitleBar::QStyleOptionTitleBar()
-    : QStyleOptionComplex(Version, SO_TitleBar), titleBarState(0), titleBarFlags(0)
+    : QStyleOptionComplex(Version, SO_TitleBar), titleBarState(0)
 {
 }
 
@@ -2954,7 +2954,7 @@ QStyleOptionTitleBar::QStyleOptionTitleBar()
     \internal
 */
 QStyleOptionTitleBar::QStyleOptionTitleBar(int version)
-    : QStyleOptionComplex(version, SO_TitleBar), titleBarState(0), titleBarFlags(0)
+    : QStyleOptionComplex(version, SO_TitleBar), titleBarState(0)
 {
 }
 

src/widgets/util/qflickgesture.cpp

@@ -610,7 +610,7 @@ QGestureRecognizer::Result QFlickGestureRecognizer::recognize(QGesture *state,
     }
 
     // depending on the scroller state return the gesture state
-    Result result(0);
+    Result result;
     bool scrollerIsActive = (scroller->state() == QScroller::Dragging ||
                              scroller->state() == QScroller::Scrolling);
 

src/widgets/widgets/qdatetimeedit.cpp

@@ -1416,9 +1416,9 @@ QDateTimeEdit::StepEnabled QDateTimeEdit::stepEnabled() const
 {
     Q_D(const QDateTimeEdit);
     if (d->readOnly)
-        return StepEnabled(0);
+        return {};
     if (d->specialValue()) {
-        return (d->minimum == d->maximum ? StepEnabled(0) : StepEnabled(StepUpEnabled));
+        return (d->minimum == d->maximum ? StepEnabled{} : StepEnabled(StepUpEnabled));
     }
 
     QAbstractSpinBox::StepEnabled ret = { };

src/widgets/widgets/qtoolbarlayout.cpp

@@ -240,9 +240,9 @@ Qt::Orientations QToolBarLayout::expandingDirections() const
         updateGeomArray();
     QToolBar *tb = qobject_cast<QToolBar*>(parentWidget());
     if (!tb)
-        return Qt::Orientations(0);
+        return {};
     Qt::Orientation o = tb->orientation();
-    return expanding ? Qt::Orientations(o) : Qt::Orientations(0);
+    return expanding ? Qt::Orientations(o) : Qt::Orientations{};
 }
 
 bool QToolBarLayout::movable() const