diff --git a/cgview/main.cpp b/cgview/main.cpp
--- a/cgview/main.cpp
+++ b/cgview/main.cpp
@@ -118,7 +118,7 @@
             return 1;
         }
     }
-    Q_ASSERT( et!=0 );
+    Q_ASSERT( et!=nullptr );
     out << "Sorted by: " << (sortByExcl ? "Exclusive ":"Inclusive ")
         << et->longName() << " (" << et->name() << ")" << endl;
 
diff --git a/kcachegrind/configdlg.h b/kcachegrind/configdlg.h
--- a/kcachegrind/configdlg.h
+++ b/kcachegrind/configdlg.h
@@ -44,8 +44,8 @@
 
 public:
     ConfigDlg(GlobalGUIConfig*, TraceData*,
-              QWidget* parent = 0);
-    ~ConfigDlg();
+              QWidget* parent = nullptr);
+    ~ConfigDlg() override;
 
     static bool configure(GlobalGUIConfig*, TraceData*, QWidget*);
 
diff --git a/kcachegrind/configdlg.cpp b/kcachegrind/configdlg.cpp
--- a/kcachegrind/configdlg.cpp
+++ b/kcachegrind/configdlg.cpp
@@ -39,9 +39,9 @@
 {
     _config = c;
     _data = data;
-    _objectCS = 0;
-    _classCS = 0;
-    _fileCS = 0;
+    _objectCS = nullptr;
+    _classCS = nullptr;
+    _fileCS = nullptr;
 
     connect(objectCombo, SIGNAL(activated(const QString &)),
             this, SLOT(objectActivated(const QString &)));
@@ -206,7 +206,7 @@
 {
     //  qDebug("objectActivated: %s", s.ascii());
 
-    if (s.isEmpty()) { _objectCS=0; return; }
+    if (s.isEmpty()) { _objectCS=nullptr; return; }
 
     QString n = ProfileContext::typeName(ProfileContext::Object) + '-' + s;
 
@@ -250,7 +250,7 @@
 {
     //  qDebug("classActivated: %s", s.ascii());
 
-    if (s.isEmpty()) { _classCS=0; return; }
+    if (s.isEmpty()) { _classCS=nullptr; return; }
 
     QString n = ProfileContext::typeName(ProfileContext::Class) + '-' + s;
 
@@ -281,7 +281,7 @@
 {
     //  qDebug("fileActivated: %s", s.ascii());
 
-    if (s.isEmpty()) { _fileCS=0; return; }
+    if (s.isEmpty()) { _fileCS=nullptr; return; }
 
     QString n = ProfileContext::typeName(ProfileContext::File) + '-' + s;
 
@@ -309,20 +309,20 @@
 QTreeWidgetItem *ConfigDlg::getSelectedDirItem()
 {
     const QList<QTreeWidgetItem*> selectedItems = dirList->selectedItems();
-    return selectedItems.count() ? selectedItems[0] : NULL;
+    return selectedItems.count() ? selectedItems[0] : nullptr;
     }
 
     void ConfigDlg::dirsItemChanged()
     {
     QTreeWidgetItem *dirItem = getSelectedDirItem();
-    deleteDirButton->setEnabled(dirItem && dirItem->parent() != NULL);
-    addDirButton->setEnabled(dirItem && dirItem->parent() == NULL);
+    deleteDirButton->setEnabled(dirItem && dirItem->parent() != nullptr);
+    addDirButton->setEnabled(dirItem && dirItem->parent() == nullptr);
 }
 
 void ConfigDlg::dirsDeletePressed()
 {
     QTreeWidgetItem *dirItem = getSelectedDirItem();
-    if (!dirItem || (dirItem->parent() == 0)) return;
+    if (!dirItem || (dirItem->parent() == nullptr)) return;
     QTreeWidgetItem* p = dirItem->parent();
     if (!p) return;
 
@@ -343,7 +343,7 @@
 void ConfigDlg::dirsAddPressed()
 {
     QTreeWidgetItem *dirItem = getSelectedDirItem();
-    if (!dirItem || (dirItem->parent() != 0)) return;
+    if (!dirItem || (dirItem->parent() != nullptr)) return;
 
     QString objName = dirItem->text(0);
 
diff --git a/kcachegrind/kdeconfig.h b/kcachegrind/kdeconfig.h
--- a/kcachegrind/kdeconfig.h
+++ b/kcachegrind/kdeconfig.h
@@ -34,11 +34,11 @@
     friend class KDEConfigStorage;
 
 public:
-    ~KDEConfigGroup();
+    ~KDEConfigGroup() override;
 
     void setValue(const QString& key, const QVariant& value,
-                  const QVariant& defaultValue = QVariant());
-    QVariant value(const QString& key, const QVariant& defaultValue) const;
+                  const QVariant& defaultValue = QVariant()) override;
+    QVariant value(const QString& key, const QVariant& defaultValue) const override;
 
 private:
     KDEConfigGroup(KConfigGroup*, bool);
@@ -55,7 +55,7 @@
 
 private:
     ConfigGroup* getGroup(const QString& group,
-                          const QString& optSuffix);
+                          const QString& optSuffix) override;
 
     KConfig* _kconfig;
 };
diff --git a/kcachegrind/kdeconfig.cpp b/kcachegrind/kdeconfig.cpp
--- a/kcachegrind/kdeconfig.cpp
+++ b/kcachegrind/kdeconfig.cpp
@@ -47,7 +47,7 @@
 void KDEConfigGroup::setValue(const QString& key, const QVariant& value,
                               const QVariant& defaultValue)
 {
-    if ((_kgroup == 0) || _readOnly) return;
+    if ((_kgroup == nullptr) || _readOnly) return;
 
     if (value == defaultValue) {
         _kgroup->deleteEntry(key);
@@ -82,7 +82,7 @@
 QVariant KDEConfigGroup::value(const QString& key,
                                const QVariant& defaultValue) const
 {
-    if (_kgroup == 0) return defaultValue;
+    if (_kgroup == nullptr) return defaultValue;
 
     switch(defaultValue.type()) {
     case QVariant::Bool:
@@ -135,7 +135,7 @@
         else if (gList.contains(group))
             g = new KConfigGroup(_kconfig, group);
         else
-            g = 0;
+            g = nullptr;
     }
     else {
         readOnly = false;
diff --git a/kcachegrind/toplevel.h b/kcachegrind/toplevel.h
--- a/kcachegrind/toplevel.h
+++ b/kcachegrind/toplevel.h
@@ -63,38 +63,38 @@
     Q_CLASSINFO("D-Bus Interface", "org.kde.kcachegrind")
 public:
     TopLevel();
-    ~TopLevel();
+    ~TopLevel() override;
 
     TraceData* data() { return _data; }
     void setData(TraceData*);
 
-    virtual void saveProperties(KConfigGroup &);
-    virtual void readProperties(const KConfigGroup &);
+    void saveProperties(KConfigGroup &) override;
+    void readProperties(const KConfigGroup &) override;
 
     void createActions();
     void createDocks();
 
     ProfileContext::Type groupType() { return _groupType; }
     EventType* eventType() { return _eventType; }
     EventType* eventType2() { return _eventType2; }
     TracePartList activeParts() { return _activeParts; }
-    TracePartList hiddenParts() { return _hiddenParts; }
+    TracePartList hiddenParts() override { return _hiddenParts; }
 
     // current config
     bool showPercentage() const { return _showPercentage; }
     bool showExpanded() const { return _showExpanded; }
     bool showCycles() const { return _showCycles; }
 
     /* convenience functions for often used context menu items */
-    void addEventTypeMenu(QMenu*,bool);
-    void addGoMenu(QMenu*);
+    void addEventTypeMenu(QMenu*,bool) override;
+    void addGoMenu(QMenu*) override;
 
     // Logger overwrites: notifications for file loading
-    virtual void loadStart(const QString& filename);
-    virtual void loadProgress(int progress); // 0 - 100
-    virtual void loadWarning(int line, const QString& msg);
-    virtual void loadError(int line, const QString& msg);
-    virtual void loadFinished(const QString& msg); // msg could be error
+    void loadStart(const QString& filename) override;
+    void loadProgress(int progress) override; // 0 - 100
+    void loadWarning(int line, const QString& msg) override;
+    void loadError(int line, const QString& msg) override;
+    void loadFinished(const QString& msg) override; // msg could be error
 
 public slots:
     void load();
@@ -130,9 +130,9 @@
     void groupTypeSelected(int);
     void splitSlot();
     void splitDirSlot();
-    void configureToolbars();
+    void configureToolbars() override;
     void configureKeys();
-    bool queryClose();
+    bool queryClose() override;
     void togglePartDock();
     void toggleStackDock();
     void toggleFunctionDock();
@@ -169,25 +169,25 @@
     bool setGroup(QString);
     bool setFunction(TraceFunction*);
     bool setFunction(QString);
-    void activePartsChangedSlot(const TracePartList& list);
+    void activePartsChangedSlot(const TracePartList& list) override;
     void partsHideSelectedSlot();
     void partsUnhideAllSlot();
 
     /* These go back to mainloop first by using a timer.
      * So they can be called from event handlers that
      * are not allowed to delete list entries.
      */
-    void setEventTypeDelayed(EventType*);
-    void setEventType2Delayed(EventType*);
-    void setGroupTypeDelayed(ProfileContext::Type);
-    void setGroupDelayed(TraceCostItem*);
-    void setTraceItemDelayed(CostItem*);
+    void setEventTypeDelayed(EventType*) override;
+    void setEventType2Delayed(EventType*) override;
+    void setGroupTypeDelayed(ProfileContext::Type) override;
+    void setGroupDelayed(TraceCostItem*) override;
+    void setTraceItemDelayed(CostItem*) override;
     void partsHideSelectedSlotDelayed();
     void partsUnhideAllSlotDelayed();
     void goBack();
     void goForward();
     void goUp();
-    void setDirectionDelayed(TraceItemView::Direction);
+    void setDirectionDelayed(TraceItemView::Direction) override;
 
     /* SingleShot Slots (without parameters) for the delayed versions */
     void setEventTypeDelayed();
@@ -199,15 +199,15 @@
     void setDirectionDelayed();
 
     // configuration has changed
-    void configChanged();
+    void configChanged() override;
 
     //void refresh();
     void slotShowTipOnStart();
     void slotShowTip();
 
     // progress in status bar, empty message disables progress display
     void showStatus(const QString& msg, int progress);
-    void showMessage(const QString&, int msec);
+    void showMessage(const QString&, int msec) override;
 
     // for running callgrind_control in the background
     void ccReadOutput();
diff --git a/kcachegrind/toplevel.cpp b/kcachegrind/toplevel.cpp
--- a/kcachegrind/toplevel.cpp
+++ b/kcachegrind/toplevel.cpp
@@ -79,15 +79,15 @@
 #include "callgraphview.h"
 
 TopLevel::TopLevel()
-    : KXmlGuiWindow(0)
+    : KXmlGuiWindow(nullptr)
 {
     QDBusConnection::sessionBus().registerObject(QStringLiteral("/KCachegrind"), this, QDBusConnection::ExportScriptableSlots);
 
-    _progressBar = 0;
+    _progressBar = nullptr;
     _statusbar = statusBar();
     _statusLabel = new QLabel(_statusbar);
     _statusbar->addWidget(_statusLabel, 1);
-    _ccProcess = 0;
+    _ccProcess = nullptr;
 
     _layoutCount = 1;
     _layoutCurrent = 0;
@@ -157,21 +157,21 @@
     _activeParts.clear();
     _hiddenParts.clear();
 
-    _data = 0;
-    _function = 0;
-    _eventType = 0;
-    _eventType2 = 0;
+    _data = nullptr;
+    _function = nullptr;
+    _eventType = nullptr;
+    _eventType2 = nullptr;
     _groupType = ProfileContext::InvalidType;
-    _group = 0;
+    _group = nullptr;
 
     // for delayed slots
-    _traceItemDelayed = 0;
-    _eventTypeDelayed = 0;
-    _eventType2Delayed = 0;
+    _traceItemDelayed = nullptr;
+    _eventTypeDelayed = nullptr;
+    _eventType2Delayed = nullptr;
     _groupTypeDelayed = ProfileContext::InvalidType;
-    _groupDelayed = 0;
+    _groupDelayed = nullptr;
     _directionDelayed = TraceItemView::None;
-    _lastSender = 0;
+    _lastSender = nullptr;
 }
 
 
@@ -1092,7 +1092,7 @@
 {
     EventType* ct;
 
-    ct = (_data) ? _data->eventTypes()->type(s) : 0;
+    ct = (_data) ? _data->eventTypes()->type(s) : nullptr;
 
     // if costtype with given name not found, use first available
     if (!ct && _data) ct = _data->eventTypes()->type(0);
@@ -1105,24 +1105,24 @@
     EventType* ct;
 
     // Special type i18n("(Hidden)") gives 0
-    ct = (_data) ? _data->eventTypes()->type(s) : 0;
+    ct = (_data) ? _data->eventTypes()->type(s) : nullptr;
 
     return setEventType2(ct);
 }
 
 void TopLevel::eventTypeSelected(const QString& s)
 {
     EventType* ct;
 
-    ct = (_data) ? _data->eventTypes()->typeForLong(s) : 0;
+    ct = (_data) ? _data->eventTypes()->typeForLong(s) : nullptr;
     setEventType(ct);
 }
 
 void TopLevel::eventType2Selected(const QString& s)
 {
     EventType* ct;
 
-    ct = (_data) ? _data->eventTypes()->typeForLong(s) : 0;
+    ct = (_data) ? _data->eventTypes()->typeForLong(s) : nullptr;
     setEventType2(ct);
 }
 
@@ -1366,9 +1366,9 @@
 
     case TraceItemView::Up:
     {
-        StackBrowser* b = _stackSelection ? _stackSelection->browser() : 0;
-        HistoryItem* hi = b ? b->current() : 0;
-        TraceFunction* f = hi ? hi->function() : 0;
+        StackBrowser* b = _stackSelection ? _stackSelection->browser() : nullptr;
+        HistoryItem* hi = b ? b->current() : nullptr;
+        TraceFunction* f = hi ? hi->function() : nullptr;
 
         if (!f) break;
         f = hi->stack()->caller(f, false);
@@ -1429,8 +1429,8 @@
     default: break;
     }
 
-    _traceItemDelayed = 0;
-    _lastSender = 0;
+    _traceItemDelayed = nullptr;
+    _lastSender = nullptr;
 }
 
 /**
@@ -1443,15 +1443,15 @@
 {
     if (data == _data) return;
 
-    _lastSender = 0;
+    _lastSender = nullptr;
 
     saveTraceSettings();
 
     if (_data) {
-        _partSelection->setData(0);
-        _stackSelection->setData(0);
-        _functionSelection->setData(0);
-        _multiView->setData(0);
+        _partSelection->setData(nullptr);
+        _stackSelection->setData(nullptr);
+        _functionSelection->setData(nullptr);
+        _multiView->setData(nullptr);
         _multiView->updateView(true);
 
         // we are the owner...
@@ -1526,7 +1526,7 @@
 void TopLevel::addEventTypeMenu(QMenu* popup, bool withCost2)
 {
     if (_data) {
-        QMenu *popup1, *popup2 = 0;
+        QMenu *popup1, *popup2 = nullptr;
         QAction* action;
 
         popup1 = popup->addMenu(i18n("Primary Event Type"));
@@ -1591,10 +1591,10 @@
 bool TopLevel::setEventType(QAction* action)
 {
     if (!_data) return false;
-    int id = action->data().toInt(0);
+    int id = action->data().toInt(nullptr);
 
     EventTypeSet* m = _data->eventTypes();
-    EventType* ct=0;
+    EventType* ct=nullptr;
     if (id >=100 && id<199) ct = m->realType(id-100);
     if (id >=200 && id<299) ct = m->derivedType(id-200);
 
@@ -1604,10 +1604,10 @@
 bool TopLevel::setEventType2(QAction* action)
 {
     if (!_data) return false;
-    int id = action->data().toInt(0);
+    int id = action->data().toInt(nullptr);
 
     EventTypeSet* m = _data->eventTypes();
-    EventType* ct=0;
+    EventType* ct=nullptr;
     if (id >=100 && id<199) ct = m->realType(id-100);
     if (id >=200 && id<299) ct = m->derivedType(id-200);
 
@@ -2031,14 +2031,14 @@
         qDebug("TopLevel::forceTrace: killing old callgrind_control");
         _ccProcess->kill();
         delete _ccProcess;
-        _ccProcess = 0;
+        _ccProcess = nullptr;
         _ccOutput = QString();
     }
     if (!_taDump->isChecked()) return;
 
     // get PID of first loaded part
     int pid = 0;
-    TracePart* p = 0;
+    TracePart* p = nullptr;
     TracePartList pl;
     if (_data) pl = _data->parts();
     if (!pl.isEmpty()) p = pl.first();
@@ -2088,7 +2088,7 @@
     showMessage(i18n("Error running callgrind_control"), 5000);
 
     _ccProcess->deleteLater();
-    _ccProcess = 0;
+    _ccProcess = nullptr;
 }
 
 void TopLevel::ccExit(int exitCode, QProcess::ExitStatus s)
@@ -2101,7 +2101,7 @@
     if (!_ccProcess) return;
     if (p != _ccProcess) return;
     _ccProcess->deleteLater();
-    _ccProcess = 0;
+    _ccProcess = nullptr;
     _taDump->setChecked(false);
 
     // if not successful no need to reload
@@ -2118,8 +2118,8 @@
     QMenu *popup = _paForward->menu();
 
     popup->clear();
-    StackBrowser* b = _stackSelection ? _stackSelection->browser() : 0;
-    HistoryItem* hi = b ? b->current() : 0;
+    StackBrowser* b = _stackSelection ? _stackSelection->browser() : nullptr;
+    HistoryItem* hi = b ? b->current() : nullptr;
     TraceFunction* f;
     QAction* action;
 
@@ -2155,8 +2155,8 @@
     QMenu *popup = _paBack->menu();
 
     popup->clear();
-    StackBrowser* b = _stackSelection ? _stackSelection->browser() : 0;
-    HistoryItem* hi = b ? b->current() : 0;
+    StackBrowser* b = _stackSelection ? _stackSelection->browser() : nullptr;
+    HistoryItem* hi = b ? b->current() : nullptr;
     TraceFunction* f;
     QAction* action;
 
@@ -2192,9 +2192,9 @@
     QMenu *popup = _paUp->menu();
 
     popup->clear();
-    StackBrowser* b = _stackSelection ? _stackSelection->browser() : 0;
-    HistoryItem* hi = b ? b->current() : 0;
-    TraceFunction* f = hi ? hi->function() : 0;
+    StackBrowser* b = _stackSelection ? _stackSelection->browser() : nullptr;
+    HistoryItem* hi = b ? b->current() : nullptr;
+    TraceFunction* f = hi ? hi->function() : nullptr;
     QAction* action;
 
     if (!f) {
@@ -2222,12 +2222,12 @@
 
 void TopLevel::forwardTriggered(QAction* action)
 {
-    int count = action->data().toInt(0);
+    int count = action->data().toInt(nullptr);
     //qDebug("forwardTriggered: %d", count);
     if( count <= 0)
         return;
 
-    StackBrowser* b = _stackSelection ? _stackSelection->browser() : 0;
+    StackBrowser* b = _stackSelection ? _stackSelection->browser() : nullptr;
     if (!b) return;
 
     while (count>1) {
@@ -2239,12 +2239,12 @@
 
 void TopLevel::backTriggered(QAction* action)
 {
-    int count = action->data().toInt(0);
+    int count = action->data().toInt(nullptr);
     //qDebug("backTriggered: %d", count);
     if( count <= 0)
         return;
 
-    StackBrowser* b = _stackSelection ? _stackSelection->browser() : 0;
+    StackBrowser* b = _stackSelection ? _stackSelection->browser() : nullptr;
     if (!b) return;
 
     while (count>1) {
@@ -2256,13 +2256,13 @@
 
 void TopLevel::upTriggered(QAction* action)
 {
-    int count = action->data().toInt(0);
+    int count = action->data().toInt(nullptr);
     //qDebug("upTriggered: %d", count);
     if( count <= 0)
         return;
 
-    StackBrowser* b = _stackSelection ? _stackSelection->browser() : 0;
-    HistoryItem* hi = b ? b->current() : 0;
+    StackBrowser* b = _stackSelection ? _stackSelection->browser() : nullptr;
+    HistoryItem* hi = b ? b->current() : nullptr;
     if (!hi) return;
 
     TraceFunction* f = hi->function();
@@ -2294,7 +2294,7 @@
         if (_progressBar) {
             _statusbar->removeWidget(_progressBar);
             delete _progressBar;
-            _progressBar = 0;
+            _progressBar = nullptr;
         }
         _statusbar->clearMessage();
         _progressMsg = msg;
diff --git a/libcore/cachegrindloader.cpp b/libcore/cachegrindloader.cpp
--- a/libcore/cachegrindloader.cpp
+++ b/libcore/cachegrindloader.cpp
@@ -40,8 +40,8 @@
 public:
     CachegrindLoader();
 
-    bool canLoad(QIODevice* file);
-    int  load(TraceData*, QIODevice* file, const QString& filename);
+    bool canLoad(QIODevice* file) override;
+    int  load(TraceData*, QIODevice* file, const QString& filename) override;
 
 private:
     void error(QString);
@@ -362,10 +362,10 @@
     int p = name.indexOf(')');
     if (p<2) {
         error(QStringLiteral("Invalid compressed ELF object ('%1')").arg(name));
-        return 0;
+        return nullptr;
     }
     int index = name.midRef(1, p-1).toInt();
-    TraceObject* o = 0;
+    TraceObject* o = nullptr;
     p++;
     while((name.length()>p) && name.at(p).isSpace()) p++;
     if (name.length()>p) {
@@ -390,9 +390,9 @@
     }
     else {
         if ((_objectVector.size() <= index) ||
-            ( (o=(TraceObject*)_objectVector.at(index)) == 0)) {
+            ( (o=(TraceObject*)_objectVector.at(index)) == nullptr)) {
             error(QStringLiteral("Undefined compressed ELF object index %1").arg(index));
-            return 0;
+            return nullptr;
         }
     }
 
@@ -410,10 +410,10 @@
     int p = name.indexOf(')');
     if (p<2) {
         error(QStringLiteral("Invalid compressed file ('%1')").arg(name));
-        return 0;
+        return nullptr;
     }
     int index = name.midRef(1, p-1).toUInt();
-    TraceFile* f = 0;
+    TraceFile* f = nullptr;
     p++;
     while((name.length()>p) && name.at(p).isSpace()) p++;
     if (name.length()>p) {
@@ -438,9 +438,9 @@
     }
     else {
         if ((_fileVector.size() <= index) ||
-            ( (f=(TraceFile*)_fileVector.at(index)) == 0)) {
+            ( (f=(TraceFile*)_fileVector.at(index)) == nullptr)) {
             error(QStringLiteral("Undefined compressed file index %1").arg(index));
-            return 0;
+            return nullptr;
         }
     }
 
@@ -461,12 +461,12 @@
     int p = name.indexOf(')');
     if (p<2) {
         error(QStringLiteral("Invalid compressed function ('%1')").arg(name));
-        return 0;
+        return nullptr;
     }
 
 
     int index = name.midRef(1, p-1).toUInt();
-    TraceFunction* f = 0;
+    TraceFunction* f = nullptr;
     p++;
     while((name.length()>p) && name.at(p).isSpace()) p++;
     if (name.length()>p) {
@@ -499,9 +499,9 @@
     }
     else {
         if ((_functionVector.size() <= index) ||
-            ( (f=(TraceFunction*)_functionVector.at(index)) == 0)) {
+            ( (f=(TraceFunction*)_functionVector.at(index)) == nullptr)) {
             error(QStringLiteral("Undefined compressed function index %1").arg(index));
-            return 0;
+            return nullptr;
         }
 
         // there was a check if the used function (returned from KCachegrinds
@@ -533,8 +533,8 @@
     }
 
     currentPartObject = currentObject->partObject(_part);
-    currentFunction = 0;
-    currentPartFunction = 0;
+    currentFunction = nullptr;
+    currentPartFunction = nullptr;
 }
 
 void CachegrindLoader::setCalledObject(const QString& name)
@@ -571,8 +571,8 @@
     }
 
     currentPartFile = currentFile->partFile(_part);
-    currentLine = 0;
-    currentPartLine = 0;
+    currentLine = nullptr;
+    currentPartLine = nullptr;
 }
 
 void CachegrindLoader::setCalledFile(const QString& name)
@@ -627,9 +627,9 @@
                                                         currentPartFile,
                                                         currentPartObject);
 
-    currentFunctionSource = 0;
-    currentLine = 0;
-    currentPartLine = 0;
+    currentFunctionSource = nullptr;
+    currentLine = nullptr;
+    currentPartLine = nullptr;
 }
 
 void CachegrindLoader::setCalledFunction(const QString& name)
@@ -669,43 +669,43 @@
     currentPos = PositionSpec();
 
     // current function/line
-    currentFunction = 0;
-    currentPartFunction = 0;
-    currentFunctionSource = 0;
-    currentFile = 0;
-    currentFunctionFile = 0;
-    currentPartFile = 0;
-    currentObject = 0;
-    currentPartObject = 0;
-    currentLine = 0;
-    currentPartLine = 0;
-    currentInstr = 0;
-    currentPartInstr = 0;
+    currentFunction = nullptr;
+    currentPartFunction = nullptr;
+    currentFunctionSource = nullptr;
+    currentFile = nullptr;
+    currentFunctionFile = nullptr;
+    currentPartFile = nullptr;
+    currentObject = nullptr;
+    currentPartObject = nullptr;
+    currentLine = nullptr;
+    currentPartLine = nullptr;
+    currentInstr = nullptr;
+    currentPartInstr = nullptr;
 
     // current call
-    currentCalledObject = 0;
-    currentCalledPartObject = 0;
-    currentCalledFile = 0;
-    currentCalledPartFile = 0;
-    currentCalledFunction = 0;
-    currentCalledPartFunction = 0;
+    currentCalledObject = nullptr;
+    currentCalledPartObject = nullptr;
+    currentCalledFile = nullptr;
+    currentCalledPartFile = nullptr;
+    currentCalledFunction = nullptr;
+    currentCalledPartFunction = nullptr;
     currentCallCount = 0;
 
     // current jump
-    currentJumpToFile = 0;
-    currentJumpToFunction = 0;
+    currentJumpToFile = nullptr;
+    currentJumpToFunction = nullptr;
     targetPos = PositionSpec();
     jumpsFollowed = 0;
     jumpsExecuted = 0;
 
-    mapping = 0;
+    mapping = nullptr;
 }
 
 void CachegrindLoader::prepareNewPart()
 {
     if (_part) {
         // really new part needed?
-        if (mapping == 0) return;
+        if (mapping == nullptr) return;
 
         // yes
         _part->invalidate();
@@ -749,7 +749,7 @@
     FixPool* pool = _data->fixPool();
 #endif
 
-    _part = 0;
+    _part = nullptr;
     partsAdded = 0;
     prepareNewPart();
 
@@ -1265,10 +1265,10 @@
                 _data->updateMaxCallCount(partLineCall->callCount());
             }
 #endif
-            currentCalledFile = 0;
-            currentCalledPartFile = 0;
-            currentCalledObject = 0;
-            currentCalledPartObject = 0;
+            currentCalledFile = nullptr;
+            currentCalledPartFile = nullptr;
+            currentCalledObject = nullptr;
+            currentCalledPartObject = nullptr;
             currentCallCount = 0;
 
             if (!line.isEmpty()) {
@@ -1347,8 +1347,8 @@
             }
 
             nextLineType = SelfCost;
-            currentJumpToFunction = 0;
-            currentJumpToFile = 0;
+            currentJumpToFunction = nullptr;
+            currentJumpToFile = nullptr;
 
             if (!line.isEmpty()) {
                 error(QStringLiteral("Garbage at end of jump cost line ('%1')").arg(line));
diff --git a/libcore/config.cpp b/libcore/config.cpp
--- a/libcore/config.cpp
+++ b/libcore/config.cpp
@@ -67,20 +67,20 @@
 // ConfigStorage
 //
 
-ConfigStorage* ConfigStorage::_storage = 0;
+ConfigStorage* ConfigStorage::_storage = nullptr;
 
 ConfigStorage::ConfigStorage()
 {
-    _storage = 0;
+    _storage = nullptr;
 }
 
 ConfigStorage::~ConfigStorage()
 {}
 
 ConfigGroup* ConfigStorage::group(const QString& group,
                                   const QString& optSuffix)
 {
-    Q_ASSERT(_storage != 0);
+    Q_ASSERT(_storage != nullptr);
 
     return _storage->getGroup(group, optSuffix);
 }
diff --git a/libcore/context.cpp b/libcore/context.cpp
--- a/libcore/context.cpp
+++ b/libcore/context.cpp
@@ -23,9 +23,9 @@
 //---------------------------------------------------
 // ProfileContext
 
-ProfileContext* ProfileContext::_contexts = 0;
-QString* ProfileContext::_typeName = 0;
-QString* ProfileContext::_i18nTypeName = 0;
+ProfileContext* ProfileContext::_contexts = nullptr;
+QString* ProfileContext::_typeName = nullptr;
+QString* ProfileContext::_i18nTypeName = nullptr;
 
 
 ProfileContext::ProfileContext(ProfileContext::Type t)
@@ -47,15 +47,15 @@
 {
     if (_typeName) {
         delete [] _typeName;
-        _typeName = 0;
+        _typeName = nullptr;
     }
     if (_i18nTypeName) {
         delete [] _i18nTypeName;
-        _i18nTypeName = 0;
+        _i18nTypeName = nullptr;
     }
     if (_contexts) {
         delete [] _contexts;
-        _contexts = 0;
+        _contexts = nullptr;
     }
 }
 
diff --git a/libcore/costitem.h b/libcore/costitem.h
--- a/libcore/costitem.h
+++ b/libcore/costitem.h
@@ -153,11 +153,11 @@
 
     explicit ProfileCostArray(ProfileContext*);
     ProfileCostArray();
-    virtual ~ProfileCostArray();
+    ~ProfileCostArray() override;
 
-    virtual QString costString(EventTypeSet*);
+    QString costString(EventTypeSet*) override;
 
-    virtual void clear();
+    void clear() override;
 
     // reserve space for cost
     void reserve(int);
@@ -178,7 +178,7 @@
     void maxCost(int index, SubCost value);
     ProfileCostArray diff(ProfileCostArray* item);
 
-    virtual void invalidate();
+    void invalidate() override;
 
     /** Returns a sub cost. This automatically triggers
      * a call to update() if needed.
@@ -193,7 +193,7 @@
     QString prettySubCostPerCall(EventType* t, uint64 calls);
 
 protected:
-    virtual void update();
+    void update() override;
 
 private:
     // Only used by friend class EventType: return subcost by index
diff --git a/libcore/costitem.cpp b/libcore/costitem.cpp
--- a/libcore/costitem.cpp
+++ b/libcore/costitem.cpp
@@ -32,8 +32,8 @@
 
 CostItem::CostItem(ProfileContext* c)
 {
-    _position = 0;
-    _dep = 0;
+    _position = nullptr;
+    _dep = nullptr;
     _dirty = true;
 
     _context = c;
@@ -85,7 +85,7 @@
 
 QString CostItem::toString()
 {
-    return QStringLiteral("%1\n  [%3]").arg(fullName()).arg(costString(0));
+    return QStringLiteral("%1\n  [%3]").arg(fullName()).arg(costString(nullptr));
 }
 
 void CostItem::invalidate()
@@ -104,22 +104,22 @@
 
 TracePart* CostItem::part()
 {
-    return _position ? _position->part() : 0;
+    return _position ? _position->part() : nullptr;
 }
 
 const TracePart* CostItem::part() const
 {
-    return _position ? _position->part() : 0;
+    return _position ? _position->part() : nullptr;
 }
 
 TraceData* CostItem::data()
 {
-    return _position ? _position->data() : 0;
+    return _position ? _position->data() : nullptr;
 }
 
 const TraceData* CostItem::data() const
 {
-    return _position ? _position->data() : 0;
+    return _position ? _position->data() : nullptr;
 }
 
 
@@ -134,19 +134,19 @@
 ProfileCostArray::ProfileCostArray(ProfileContext* context)
     : CostItem(context)
 {
-    _cachedType = 0; // no virtual value cached
+    _cachedType = nullptr; // no virtual value cached
     _allocCount = 0;
     _count = 0;
-    _cost = 0;
+    _cost = nullptr;
 }
 
 ProfileCostArray::ProfileCostArray()
     : CostItem(ProfileContext::context(ProfileContext::UnknownType))
 {
-    _cachedType = 0; // no virtual value cached
+    _cachedType = nullptr; // no virtual value cached
     _allocCount = 0;
     _count = 0;
-    _cost = 0;
+    _cost = nullptr;
 }
 
 ProfileCostArray::~ProfileCostArray()
@@ -567,7 +567,7 @@
 {
     if (_dirty) return;
     _dirty = true;
-    _cachedType = 0; // cached value is invalid, too
+    _cachedType = nullptr; // cached value is invalid, too
 
     if (_dep)
         _dep->invalidate();
diff --git a/libcore/coverage.h b/libcore/coverage.h
--- a/libcore/coverage.h
+++ b/libcore/coverage.h
@@ -47,7 +47,7 @@
 
     Coverage();
 
-    virtual int rtti() { return Rtti; }
+    int rtti() override { return Rtti; }
     void init();
 
     TraceFunction* function() { return _function; }
diff --git a/libcore/eventtype.cpp b/libcore/eventtype.cpp
--- a/libcore/eventtype.cpp
+++ b/libcore/eventtype.cpp
@@ -26,16 +26,16 @@
 //---------------------------------------------------
 // EventType
 
-QList<EventType*>* EventType::_knownTypes = 0;
+QList<EventType*>* EventType::_knownTypes = nullptr;
 
 EventType::EventType(const QString& name, const QString& longName,
                      const QString& formula)
 {
     _name = name;
     _longName = longName;
     _formula = formula;
     _isReal = formula.isEmpty();
-    _set = 0;
+    _set = nullptr;
     _realIndex = ProfileCostArray::InvalidIndex;
     _parsed = false;
     _inParsing = false;
@@ -255,37 +255,37 @@
 
 EventType* EventType::cloneKnownRealType(const QString& n)
 {
-    if (!_knownTypes) return 0;
+    if (!_knownTypes) return nullptr;
 
     foreach (EventType* t, *_knownTypes)
         if (t->isReal() && (t->name() == n)) {
             EventType* type = new EventType(*t);
             return type;
         }
 
-    return 0;
+    return nullptr;
 }
 
 
 EventType* EventType::cloneKnownDerivedType(const QString& n)
 {
-    if (!_knownTypes) return 0;
+    if (!_knownTypes) return nullptr;
 
     foreach (EventType* t, *_knownTypes)
         if (!t->isReal() && (t->name() == n)) {
             EventType* type = new EventType(*t);
             return type;
         }
 
-    return 0;
+    return nullptr;
 }
 
 // we take ownership
 void EventType::add(EventType* t, bool overwriteExisting)
 {
     if (!t) return;
 
-    t->setEventTypeSet(0);
+    t->setEventTypeSet(nullptr);
 
     if (!_knownTypes)
         _knownTypes = new QList<EventType*>;
@@ -332,8 +332,8 @@
 
 EventType* EventType::knownType(int i)
 {
-    if (!_knownTypes) return 0;
-    if (i<0 || i>=(int)_knownTypes->count()) return 0;
+    if (!_knownTypes) return nullptr;
+    if (i<0 || i>=(int)_knownTypes->count()) return nullptr;
 
     return _knownTypes->at(i);
 }
@@ -346,8 +346,8 @@
 {
     _realCount = 0;
     _derivedCount = 0;
-    for (int i=0;i<ProfileCostArray::MaxRealIndex;i++) _real[i] = 0;
-    for (int i=0;i<ProfileCostArray::MaxRealIndex;i++) _derived[i] = 0;
+    for (int i=0;i<ProfileCostArray::MaxRealIndex;i++) _real[i] = nullptr;
+    for (int i=0;i<ProfileCostArray::MaxRealIndex;i++) _derived[i] = nullptr;
 }
 
 EventTypeSet::~EventTypeSet()
@@ -383,7 +383,7 @@
         qDebug() << "EventTypeSet::createMapping: No space for "
                  << newCount << " cost entries.";
         qDebug() << "Increase MaxRealIndexValue in libcore/costitem.h and recompile.";
-        return 0;
+        return nullptr;
     }
 
     EventTypeMapping* mapping = new EventTypeMapping(this);
@@ -470,7 +470,7 @@
     EventType::remove(t->name());
 
     // delete this type
-    _derived[i] = 0;
+    _derived[i] = nullptr;
     delete t;
     if (i+1 == _derivedCount) {
         // we can reuse the last index
@@ -482,27 +482,27 @@
 
 EventType* EventTypeSet::realType(int t)
 {
-    if (t<0 || t>=_realCount) return 0;
+    if (t<0 || t>=_realCount) return nullptr;
     return _real[t];
 }
 
 EventType* EventTypeSet::derivedType(int t)
 {
-    if (t<0 || t>=_derivedCount) return 0;
+    if (t<0 || t>=_derivedCount) return nullptr;
     return _derived[t];
 }
 
 
 EventType* EventTypeSet::type(int t)
 {
-    if (t<0) return 0;
+    if (t<0) return nullptr;
     if (t<_realCount) return _real[t];
 
     t -= ProfileCostArray::MaxRealIndex;
-    if (t<0) return 0;
+    if (t<0) return nullptr;
     if (t<_derivedCount) return _derived[t];
 
-    return 0;
+    return nullptr;
 }
 
 EventType* EventTypeSet::type(const QString& name)
@@ -515,7 +515,7 @@
         if (_derived[i] && (_derived[i]->name() == name))
             return _derived[i];
 
-    return 0;
+    return nullptr;
 }
 
 EventType* EventTypeSet::typeForLong(const QString& name)
@@ -528,7 +528,7 @@
         if (_derived[i] && (_derived[i]->longName() == name))
             return _derived[i];
 
-    return 0;
+    return nullptr;
 }
 
 
@@ -571,7 +571,7 @@
                 addDiff++;
                 add(new EventType(t->name(), t->longName(), t->formula()));
             }
-            t->setEventTypeSet(0);
+            t->setEventTypeSet(nullptr);
         }
         if (addDiff == 0) break;
         addCount += addDiff;
diff --git a/libcore/fixcost.cpp b/libcore/fixcost.cpp
--- a/libcore/fixcost.cpp
+++ b/libcore/fixcost.cpp
@@ -47,7 +47,7 @@
         _count = 0;
 
     _nextCostOfPartFunction = partFunction ?
-                                  partFunction->setFirstFixCost(this) : 0;
+                                  partFunction->setFirstFixCost(this) : nullptr;
 }
 
 void* FixCost::operator new(size_t size, FixPool* pool)
@@ -103,7 +103,7 @@
     else
         _cost[_count] = callCount;
 
-    _nextCostOfPartCall = partCall ? partCall->setFirstFixCallCost(this) : 0;
+    _nextCostOfPartCall = partCall ? partCall->setFirstFixCallCost(this) : nullptr;
 }
 
 void* FixCallCost::operator new(size_t size, FixPool* pool)
@@ -171,7 +171,7 @@
     if (isCondJump) _cost[1] = followed;
 
     _nextJumpOfPartFunction = partFunction ?
-                                  partFunction->setFirstFixJump(this) : 0;
+                                  partFunction->setFirstFixJump(this) : nullptr;
 }
 
 void* FixJump::operator new(size_t size, FixPool* pool)
diff --git a/libcore/globalconfig.h b/libcore/globalconfig.h
--- a/libcore/globalconfig.h
+++ b/libcore/globalconfig.h
@@ -48,7 +48,7 @@
     virtual void saveOptions();
     virtual void readOptions();
 
-    static QStringList sourceDirs(TraceData*, TraceObject* o = 0);
+    static QStringList sourceDirs(TraceData*, TraceObject* o = nullptr);
     static bool showPercentage();
     static bool showExpanded();
     static bool showCycles();
diff --git a/libcore/globalconfig.cpp b/libcore/globalconfig.cpp
--- a/libcore/globalconfig.cpp
+++ b/libcore/globalconfig.cpp
@@ -114,11 +114,11 @@
 }
 
 
-GlobalConfig* GlobalConfig::_config = 0;
+GlobalConfig* GlobalConfig::_config = nullptr;
 
 GlobalConfig::GlobalConfig()
 {
-    _config = 0;
+    _config = nullptr;
 
     // general presentation options
     _showPercentage   = DEFAULT_SHOWPERCENTAGE;
@@ -144,7 +144,7 @@
 
 GlobalConfig* GlobalConfig::config()
 {
-    if (_config == 0)
+    if (_config == nullptr)
         _config = new GlobalConfig();
 
     return _config;
diff --git a/libcore/loader.cpp b/libcore/loader.cpp
--- a/libcore/loader.cpp
+++ b/libcore/loader.cpp
@@ -33,7 +33,7 @@
     _name = name;
     _description = desc;
 
-    _logger = 0;
+    _logger = nullptr;
 }
 
 Loader::~Loader()
@@ -55,16 +55,16 @@
         if (l->canLoad(file))
             return l;
 
-    return 0;
+    return nullptr;
 }
 
 Loader* Loader::loader(const QString& name)
 {
     foreach (Loader* l, _loaderList)
         if (l->name() == name)
             return l;
 
-    return 0;
+    return nullptr;
 }
 
 // factories of available loaders
diff --git a/libcore/pool.cpp b/libcore/pool.cpp
--- a/libcore/pool.cpp
+++ b/libcore/pool.cpp
@@ -35,7 +35,7 @@
 
 FixPool::FixPool()
 {
-    _first = _last = 0;
+    _first = _last = nullptr;
     _reservation = 0;
     _count = 0;
     _size = 0;
@@ -57,7 +57,7 @@
 
 void* FixPool::allocate(unsigned int size)
 {
-    if (!ensureSpace(size)) return 0;
+    if (!ensureSpace(size)) return nullptr;
 
     _reservation = 0;
     void* result = _last->space + _last->used;
@@ -71,7 +71,7 @@
 
 void* FixPool::reserve(unsigned int size)
 {
-    if (!ensureSpace(size)) return 0;
+    if (!ensureSpace(size)) return nullptr;
     _reservation = size;
 
     return _last->space + _last->used;
@@ -108,7 +108,7 @@
                "this system. You could try loading this file on a 64-bit OS.");
         exit(1);
     }
-    newChunk->next = 0;
+    newChunk->next = nullptr;
     newChunk->used = 0;
 
     if (!_last) {
@@ -171,8 +171,8 @@
         (*(char**)(*ptr - 4)) != (char*)ptr )
         qFatal("Chaining error in DynPool::free");
 
-    (*(char**)(*ptr - 4)) = 0;
-    *ptr = 0;
+    (*(char**)(*ptr - 4)) = nullptr;
+    *ptr = nullptr;
 }
 
 bool DynPool::ensureSpace(unsigned int size)
@@ -198,7 +198,7 @@
                       p, len, p[1], freed, pnew);
 
         /* skip freed space ? */
-        if (p[1] == 0) {
+        if (p[1] == nullptr) {
             freed += len;
             p = pnext;
             continue;
@@ -224,7 +224,7 @@
         pnew = (char**) pnew[0];
         p = pnext;
     }
-    pnew[0] = 0;
+    pnew[0] = nullptr;
 
     unsigned int newused = (char*)pnew - (char*)newdata;
     qDebug("DynPool::ensureSpace size: %d => %d, used %d => %d (%d freed)",
diff --git a/libcore/stackbrowser.cpp b/libcore/stackbrowser.cpp
--- a/libcore/stackbrowser.cpp
+++ b/libcore/stackbrowser.cpp
@@ -55,15 +55,15 @@
 
     // event type to use for the "most probable" call stack
     // we simply take the first real event type
-    if ((_top->data() == 0) ||
+    if ((_top->data() == nullptr) ||
         (_top->data()->eventTypes()->realCount() <1)) return;
     EventType* e = _top->data()->eventTypes()->realType(0);
 
     int max = 30;
 
     // try to extend to lower stack frames
     while (f && (max-- >0)) {
-        TraceCall* call = 0;
+        TraceCall* call = nullptr;
         most = 0;
         foreach(TraceCall* c, f->callings()) {
             // no cycle calls in stack: could be deleted without notice
@@ -100,13 +100,13 @@
 
     // event type to use for the "most probable" call stack
     // we simply take the first real event type
-    if ((_top->data() == 0) ||
+    if ((_top->data() == nullptr) ||
         (_top->data()->eventTypes()->realCount() <1)) return;
     EventType* e = _top->data()->eventTypes()->realType(0);
 
     // try to extend to upper stack frames
     while (_top && (max-- >0)) {
-        TraceCall* call = 0;
+        TraceCall* call = nullptr;
         most = 0;
         foreach(TraceCall* c, _top->callers()) {
             // no cycle calls in stack: could be deleted without notice
@@ -146,7 +146,7 @@
         if (f == fn)
             return c->caller();
     }
-    return 0;
+    return nullptr;
 }
 
 TraceFunction* Stack::called(TraceFunction* fn, bool extend)
@@ -171,7 +171,7 @@
         }
     }
 
-    return 0;
+    return nullptr;
 }
 
 bool Stack::contains(TraceFunction* fn)
@@ -223,8 +223,8 @@
     TraceCallList calls = _calls;
 
     // cycles are listed on there own
-    if (f->cycle() == f) return 0;
-    if (_top->cycle() == _top) return 0;
+    if (f->cycle() == f) return nullptr;
+    if (_top->cycle() == _top) return nullptr;
 
     foreach(TraceCall* c, calls) {
         foreach(TraceCall* c2, c->called()->callings()) {
@@ -239,7 +239,7 @@
             return new Stack(_top, calls);
         }
     }
-    return 0;
+    return nullptr;
 }
 
 QString Stack::toString()
@@ -261,8 +261,8 @@
     if (_stack)
         _stack->ref();
 
-    _last = 0;
-    _next = 0;
+    _last = nullptr;
+    _next = nullptr;
 
     /*
   qDebug("New Stack History Item (sRef %d): %s\n  %s",
@@ -290,7 +290,7 @@
 
 StackBrowser::StackBrowser()
 {
-    _current = 0;
+    _current = nullptr;
 }
 
 StackBrowser::~StackBrowser()
@@ -309,7 +309,7 @@
         HistoryItem* item = _current;
         if (item->next()) {
             item = item->next();
-            item->last()->setNext(0);
+            item->last()->setNext(nullptr);
 
             while (item->next()) {
                 item = item->next();
diff --git a/libcore/subcost.h b/libcore/subcost.h
--- a/libcore/subcost.h
+++ b/libcore/subcost.h
@@ -89,7 +89,7 @@
     int maxSize() { return _maxSize; }
     bool hasMore() { return _count > _maxSize; }
     ProfileCostArray* operator[] (int i)
-    { return (i>=0 && i<_count && i<_maxSize) ? _item[i] : 0; }
+    { return (i>=0 && i<_count && i<_maxSize) ? _item[i] : nullptr; }
 
 private:
     TraceCostList _list;
diff --git a/libcore/subcost.cpp b/libcore/subcost.cpp
--- a/libcore/subcost.cpp
+++ b/libcore/subcost.cpp
@@ -68,7 +68,7 @@
 
 HighestCostList::HighestCostList()
 {
-    _costType = 0;
+    _costType = nullptr;
     clear(1);
 }
 
diff --git a/libcore/tracedata.h b/libcore/tracedata.h
--- a/libcore/tracedata.h
+++ b/libcore/tracedata.h
@@ -202,11 +202,11 @@
 {
 public:
     explicit TraceJumpCost(ProfileContext*);
-    virtual ~TraceJumpCost();
+    ~TraceJumpCost() override;
 
     // reimplementations for cost addition
-    virtual QString costString(EventTypeSet* m);
-    virtual void clear();
+    QString costString(EventTypeSet* m) override;
+    void clear() override;
 
     void addCost(TraceJumpCost*);
 
@@ -229,11 +229,11 @@
 {
 public:
     explicit TraceCallCost(ProfileContext*);
-    virtual ~TraceCallCost();
+    ~TraceCallCost() override;
 
     // reimplementations for cost addition
-    virtual QString costString(EventTypeSet* m);
-    virtual void clear();
+    QString costString(EventTypeSet* m) override;
+    void clear() override;
 
     // additional cost metric
     SubCost callCount();
@@ -252,11 +252,11 @@
 {
 public:
     explicit TraceInclusiveCost(ProfileContext*);
-    virtual ~TraceInclusiveCost();
+    ~TraceInclusiveCost() override;
 
     // reimplementations for cost addition
-    virtual QString costString(EventTypeSet* m);
-    virtual void clear();
+    QString costString(EventTypeSet* m) override;
+    void clear() override;
 
     // additional cost metric
     ProfileCostArray* inclusive();
@@ -275,10 +275,10 @@
 {
 public:
     explicit TraceListCost(ProfileContext*);
-    virtual ~TraceListCost();
+    ~TraceListCost() override;
 
     // reimplementation for dependency list
-    virtual void update();
+    void update() override;
 
     TraceCostList& deps() { return _deps; }
     void addDep(ProfileCostArray*);
@@ -304,10 +304,10 @@
 {
 public:
     explicit TraceJumpListCost(ProfileContext*);
-    virtual ~TraceJumpListCost();
+    ~TraceJumpListCost() override;
 
     // reimplementation for dependency list
-    virtual void update();
+    void update() override;
 
     TraceJumpCostList deps() { return _deps; }
     void addDep(TraceJumpCost*);
@@ -335,10 +335,10 @@
 {
 public:
     explicit TraceCallListCost(ProfileContext*);
-    virtual ~TraceCallListCost();
+    ~TraceCallListCost() override;
 
     // reimplementation for dependency list
-    virtual void update();
+    void update() override;
 
     TraceCallCostList deps() { return _deps; }
     void addDep(TraceCallCost*);
@@ -363,10 +363,10 @@
 {
 public:
     explicit TraceInclusiveListCost(ProfileContext*);
-    virtual ~TraceInclusiveListCost();
+    ~TraceInclusiveListCost() override;
 
     // reimplementation for dependency
-    virtual void update();
+    void update() override;
 
     TraceInclusiveCostList deps() { return _deps; }
     void addDep(TraceInclusiveCost*);
@@ -399,10 +399,10 @@
 {
 public:
     TracePartInstrJump(TraceInstrJump*, TracePartInstrJump*);
-    virtual ~TracePartInstrJump();
+    ~TracePartInstrJump() override;
 
     // fix cost item
-    virtual void update() {}
+    void update() override {}
     TraceInstrJump* instrJump() const { return (TraceInstrJump*) _dep; }
     TracePartInstrJump* next() const { return _next; }
 
@@ -420,10 +420,10 @@
 {
 public:
     explicit TracePartInstrCall(TraceInstrCall*);
-    virtual ~TracePartInstrCall();
+    ~TracePartInstrCall() override;
 
     // fix cost item
-    virtual void update() {}
+    void update() override {}
     TraceInstrCall* instrCall() const { return (TraceInstrCall*) _dep; }
 };
 
@@ -436,10 +436,10 @@
 {
 public:
     explicit TracePartInstr(TraceInstr*);
-    virtual ~TracePartInstr();
+    ~TracePartInstr() override;
 
     // fix cost item
-    virtual void update() {}
+    void update() override {}
 
     TraceInstr* instr() const { return (TraceInstr*)_dep; }
 };
@@ -452,10 +452,10 @@
 {
 public:
     explicit TracePartLineJump(TraceLineJump*);
-    virtual ~TracePartLineJump();
+    ~TracePartLineJump() override;
 
     // fix cost item
-    virtual void update() {}
+    void update() override {}
     TraceLineJump* lineJump() const { return (TraceLineJump*) _dep; }
 };
 
@@ -468,10 +468,10 @@
 {
 public:
     explicit TracePartLineCall(TraceLineCall*);
-    virtual ~TracePartLineCall();
+    ~TracePartLineCall() override;
 
     // fix cost item
-    virtual void update() {}
+    void update() override {}
     TraceLineCall* lineCall() const { return (TraceLineCall*) _dep; }
 };
 
@@ -485,10 +485,10 @@
 {
 public:
     explicit TracePartLine(TraceLine*);
-    virtual ~TracePartLine();
+    ~TracePartLine() override;
 
     // fix cost item
-    virtual void update() {}
+    void update() override {}
 
     TraceLine* line() const { return (TraceLine*)_dep; }
 };
@@ -501,9 +501,9 @@
 {
 public:
     explicit TracePartLineRegion(TraceLineRegion*);
-    virtual ~TracePartLineRegion();
+    ~TracePartLineRegion() override;
 
-    virtual void update();
+    void update() override;
 
     TraceLineRegion* region() const { return (TraceLineRegion*)_dep; }
 };
@@ -517,13 +517,13 @@
 {
 public:
     explicit TracePartCall(TraceCall* call);
-    virtual ~TracePartCall();
+    ~TracePartCall() override;
 
     // calls a function itself?
     bool isRecursion();
 
     // reimplementation for dependency list
-    virtual void update();
+    void update() override;
 
     TraceCall* call() const { return (TraceCall*)_dep; }
 
@@ -545,10 +545,10 @@
 public:
     TracePartFunction(TraceFunction*,
                       TracePartObject*, TracePartFile*);
-    virtual ~TracePartFunction();
+    ~TracePartFunction() override;
 
-    virtual void update();
-    virtual QString costString(EventTypeSet* m);
+    void update() override;
+    QString costString(EventTypeSet* m) override;
 
     void addPartInstr(TracePartInstr*);
     void addPartLine(TracePartLine*);
@@ -608,9 +608,9 @@
 {
 public:
     explicit TracePartClass(TraceClass*);
-    virtual ~TracePartClass();
+    ~TracePartClass() override;
 
-    QString prettyName() const;
+    QString prettyName() const override;
 
     TraceClass* cls() { return (TraceClass*)_dep; }
     void addPartFunction(TracePartFunction* f) { addDep(f); }
@@ -625,7 +625,7 @@
 {
 public:
     explicit TracePartFile(TraceFile*);
-    virtual ~TracePartFile();
+    ~TracePartFile() override;
 
     TraceFile* file() { return (TraceFile*)_dep; }
     void addPartFunction(TracePartFunction* f) { addDep(f); }
@@ -640,7 +640,7 @@
 {
 public:
     explicit TracePartObject(TraceObject*);
-    virtual ~TracePartObject();
+    ~TracePartObject() override;
 
     TraceObject* object() const { return (TraceObject*)_dep; }
     void addPartFunction(TracePartFunction* f) { addDep(f); }
@@ -656,15 +656,15 @@
 {
 public:
     explicit TracePart(TraceData*);
-    virtual ~TracePart();
+    ~TracePart() override;
 
-    virtual TracePart* part() { return this; }
-    virtual const TracePart* part() const { return this; }
+    TracePart* part() override { return this; }
+    const TracePart* part() const override { return this; }
 
     QString shortName() const;
-    QString prettyName() const;
+    QString prettyName() const override;
     /// @return Name of the file this part was loaded from
-    QString name() const { return _name; }
+    QString name() const override { return _name; }
     QString description() const { return _descr; }
     QString trigger() const { return _trigger; }
     QString timeframe() const { return _timeframe; }
@@ -726,11 +726,11 @@
 public:
     TraceInstrJump(TraceInstr* instrFrom, TraceInstr* instrTo,
                    bool isCondJump);
-    virtual ~TraceInstrJump();
+    ~TraceInstrJump() override;
 
-    virtual QString name() const;
+    QString name() const override;
 
-    virtual void update();
+    void update() override;
 
     TraceInstr* instrFrom() const { return _instrFrom; }
     TraceInstr* instrTo() const { return _instrTo; }
@@ -755,9 +755,9 @@
 public:
     TraceLineJump(TraceLine* lineFrom, TraceLine* lineTo,
                   bool isCondJump);
-    virtual ~TraceLineJump();
+    ~TraceLineJump() override;
 
-    virtual QString name() const;
+    QString name() const override;
 
     TraceLine* lineFrom() const { return _lineFrom; }
     TraceLine* lineTo() const { return _lineTo; }
@@ -767,7 +767,7 @@
     TracePartLineJump* partLineJump(TracePart*);
 
 protected:
-    bool onlyActiveParts() { return true; }
+    bool onlyActiveParts() override { return true; }
 
 private:
     TraceLine *_lineFrom, *_lineTo;
@@ -782,18 +782,18 @@
 {
 public:
     TraceInstrCall(TraceCall* call, TraceInstr* instr);
-    virtual ~TraceInstrCall();
+    ~TraceInstrCall() override;
 
-    virtual QString name() const;
+    QString name() const override;
 
     TraceInstr* instr() const { return _instr; }
     TraceCall* call() const { return _call; }
 
     // part factory
     TracePartInstrCall* partInstrCall(TracePart*, TracePartCall*);
 
 protected:
-    bool onlyActiveParts() { return true; }
+    bool onlyActiveParts() override { return true; }
 
 private:
     TraceInstr* _instr;
@@ -808,18 +808,18 @@
 {
 public:
     TraceLineCall(TraceCall* call, TraceLine* line);
-    virtual ~TraceLineCall();
+    ~TraceLineCall() override;
 
-    virtual QString name() const;
+    QString name() const override;
 
     TraceLine* line() const { return _line; }
     TraceCall* call() const { return _call; }
 
     // part factory
     TracePartLineCall* partLineCall(TracePart*, TracePartCall*);
 
 protected:
-    bool onlyActiveParts() { return true; }
+    bool onlyActiveParts() override { return true; }
 
 private:
     TraceLine* _line;
@@ -835,17 +835,17 @@
 {
 public:
     TraceCall(TraceFunction* caller, TraceFunction* called);
-    virtual ~TraceCall();
+    ~TraceCall() override;
 
-    virtual QString name() const;
+    QString name() const override;
 
     // calls a function itself?
     bool isRecursion() { return _caller == _called; }
 
     // return cycle number >0 if call is inside of a cycle
     int inCycle();
     // we need some special handling for cycle calls
-    void update();
+    void update() override;
 
     void invalidateDynamicCost();
 
@@ -866,7 +866,7 @@
     { FixCallCost* t = _firstFixCost; _firstFixCost = fc; return t; }
 
 protected:
-    bool onlyActiveParts() { return true; }
+    bool onlyActiveParts() override { return true; }
 
 private:
     TraceInstrCallList _instrCalls;
@@ -887,10 +887,10 @@
 {
 public:
     TraceInstr();
-    virtual ~TraceInstr();
+    ~TraceInstr() override;
 
-    virtual QString name() const;
-    QString prettyName() const;
+    QString name() const override;
+    QString prettyName() const override;
 
     bool isValid() { return _addr != Addr(0); }
 
@@ -914,7 +914,7 @@
     void setLine(TraceLine* l) { _line = l; }
 
 protected:
-    bool onlyActiveParts() { return true; }
+    bool onlyActiveParts() override { return true; }
 
 private:
     Addr _addr;
@@ -935,10 +935,10 @@
 {
 public:
     TraceLine();
-    virtual ~TraceLine();
+    ~TraceLine() override;
 
-    virtual QString name() const;
-    QString prettyName() const;
+    QString name() const override;
+    QString prettyName() const override;
 
     // factories
     TracePartLine* partLine(TracePart* part,
@@ -948,7 +948,7 @@
     void addLineCall(TraceLineCall*);
 
 
-    bool isValid() { return _sourceFile != 0; }
+    bool isValid() { return _sourceFile != nullptr; }
     bool hasCost(EventType*);
     TraceFunctionSource* functionSource() const { return _sourceFile; }
     uint lineno() const { return _lineno; }
@@ -960,7 +960,7 @@
     void setLineno(uint lineno) { _lineno = lineno; }
 
 protected:
-    bool onlyActiveParts() { return true; }
+    bool onlyActiveParts() override { return true; }
 
 private:
     TraceFunctionSource* _sourceFile;
@@ -980,13 +980,13 @@
 {
 public:
     explicit TraceCostItem(ProfileContext*);
-    virtual ~TraceCostItem();
+    ~TraceCostItem() override;
 
-    virtual QString name() const { return _name; }
+    QString name() const override { return _name; }
     virtual void setName(const QString& name) { _name = name; }
 
 protected:
-    bool onlyActiveParts() { return true; }
+    bool onlyActiveParts() override { return true; }
 
 protected:
     QString _name;
@@ -1000,13 +1000,13 @@
 {
 public:
     TraceLineRegion(uint from, uint to, QString name);
-    virtual ~TraceLineRegion();
+    ~TraceLineRegion() override;
 
-    virtual void update();
+    void update() override;
 
     uint from() const { return _from; }
     uint to() const { return _to; }
-    QString name() const { return _name; }
+    QString name() const override { return _name; }
 
     // factories
     TracePartLine* partLineRegion(TracePart* part,
@@ -1029,12 +1029,12 @@
 {
 public:
     TraceFunctionSource(TraceFunction*, TraceFile*);
-    virtual ~TraceFunctionSource();
+    ~TraceFunctionSource() override;
 
-    virtual QString name() const;
+    QString name() const override;
 
     // reimplementation for dependency map
-    virtual void update();
+    void update() override;
 
     TraceFile* file() const { return _file; }
     TraceFunction* function() const { return _function; }
@@ -1124,9 +1124,9 @@
     TraceFunction();
     TraceFunction(TraceData* data, const QString& name,
                   TraceClass* cls, TraceFile* file, TraceObject* object);
-    virtual ~TraceFunction();
+    ~TraceFunction() override;
 
-    virtual void update();
+    void update() override;
 
     // this invalidate all subcosts of function depending on
     // active status of parts
@@ -1149,8 +1149,8 @@
      */
     QString location(int maxFiles = 0) const;
 
-    QString prettyName() const;
-    QString formattedName() const;
+    QString prettyName() const override;
+    QString formattedName() const override;
     static QString prettyEmptyName();
     QString prettyLocation(int maxFiles = 0) const;
     QString prettyNameWithLocation(int maxFiles = 1) const;
@@ -1162,7 +1162,7 @@
     TraceFile* file() const { return _file; }
     TraceObject* object() const { return _object; }
     // get the source file with lines from function declaration (not inlined)
-    TraceFunctionSource* sourceFile(TraceFile* file = 0,
+    TraceFunctionSource* sourceFile(TraceFile* file = nullptr,
                                     bool createNew = false);
     const TraceFunctionSourceList& sourceFiles() const
     { return _sourceFiles; }
@@ -1271,9 +1271,9 @@
 {
 public:
     TraceClass();
-    virtual ~TraceClass();
+    ~TraceClass() override;
 
-    virtual QString prettyName() const;
+    QString prettyName() const override;
     static QString prettyEmptyName();
 
     void addFunction(TraceFunction*);
@@ -1295,7 +1295,7 @@
 {
 public:
     TraceFile();
-    virtual ~TraceFile();
+    ~TraceFile() override;
 
     void setDirectory(const QString& dir);
     void resetDirectory() { _dir = QString(); }
@@ -1306,7 +1306,7 @@
 
     // without path
     QString shortName() const;
-    QString prettyName() const;
+    QString prettyName() const override;
     QString prettyLongName() const;
     static QString prettyEmptyName();
     const TraceFunctionList& functions() const { return _functions; }
@@ -1331,16 +1331,16 @@
 {
 public:
     TraceObject();
-    virtual ~TraceObject();
+    ~TraceObject() override;
 
     void setDirectory(const QString& dir);
     void resetDirectory() { _dir = QString(); }
     QString directory();
 
     void addFunction(TraceFunction*);
 
     QString shortName() const;
-    QString prettyName() const;
+    QString prettyName() const override;
     static QString prettyEmptyName();
     const TraceFunctionList& functions() const { return _functions; }
 
@@ -1365,11 +1365,11 @@
     // profiled architecture (must be same for every part)
     enum Arch { ArchUnknown, ArchARM };
 
-    explicit TraceData(Logger* l = 0);
-    virtual ~TraceData();
+    explicit TraceData(Logger* l = nullptr);
+    ~TraceData() override;
 
-    virtual TraceData* data() { return this; }
-    virtual const TraceData* data() const { return this; }
+    TraceData* data() override { return this; }
+    const TraceData* data() const override { return this; }
 
     /**
      * Loads profile data files.
@@ -1430,7 +1430,7 @@
      * is not needed.
      */
     ProfileCostArray* search(ProfileContext::Type, QString,
-                             EventType* ct = 0, ProfileCostArray* parent = 0);
+                             EventType* ct = nullptr, ProfileCostArray* parent = nullptr);
 
     // for pretty function names without signature if unique...
     TraceFunctionMap::Iterator functionIterator(TraceFunction*);
@@ -1461,7 +1461,7 @@
     // reset all manually set directories for source files
     void resetSourceDirs();
 
-    virtual void update();
+    void update() override;
 
     // invalidates all cost items dependant on active state of parts
     void invalidateDynamicCost();
diff --git a/libcore/tracedata.cpp b/libcore/tracedata.cpp
--- a/libcore/tracedata.cpp
+++ b/libcore/tracedata.cpp
@@ -181,7 +181,7 @@
 TraceListCost::TraceListCost(ProfileContext* context)
     : ProfileCostArray(context)
 {
-    _lastDep = 0;
+    _lastDep = nullptr;
 }
 
 TraceListCost::~TraceListCost()
@@ -219,7 +219,7 @@
             return dep;
         }
     }
-    return 0;
+    return nullptr;
 }
 
 
@@ -255,7 +255,7 @@
 TraceJumpListCost::TraceJumpListCost(ProfileContext* context)
     : TraceJumpCost(context)
 {
-    _lastDep = 0;
+    _lastDep = nullptr;
 }
 
 TraceJumpListCost::~TraceJumpListCost()
@@ -293,7 +293,7 @@
             return dep;
         }
     }
-    return 0;
+    return nullptr;
 }
 
 
@@ -329,7 +329,7 @@
 TraceCallListCost::TraceCallListCost(ProfileContext* context)
     : TraceCallCost(context)
 {
-    _lastDep = 0;
+    _lastDep = nullptr;
 }
 
 TraceCallListCost::~TraceCallListCost()
@@ -367,7 +367,7 @@
             return dep;
         }
     }
-    return 0;
+    return nullptr;
 }
 
 
@@ -407,7 +407,7 @@
 TraceInclusiveListCost::TraceInclusiveListCost(ProfileContext* context)
     : TraceInclusiveCost(context)
 {
-    _lastDep = 0;
+    _lastDep = nullptr;
 }
 
 TraceInclusiveListCost::~TraceInclusiveListCost()
@@ -446,7 +446,7 @@
             return dep;
         }
     }
-    return 0;
+    return nullptr;
 }
 
 void TraceInclusiveListCost::update()
@@ -568,7 +568,7 @@
 {
     _dep = call;
 
-    _firstFixCallCost = 0;
+    _firstFixCallCost = nullptr;
 }
 
 TracePartCall::~TracePartCall()
@@ -621,15 +621,15 @@
     _dep = function;
     _partObject = partObject;
     _partFile = partFile;
-    _partClass = 0;
+    _partClass = nullptr;
 
     _calledCount     = 0;
     _callingCount    = 0;
     _calledContexts  = 0;
     _callingContexts = 0;
 
-    _firstFixCost = 0;
-    _firstFixJump = 0;
+    _firstFixCost = nullptr;
+    _firstFixJump = nullptr;
 }
 
 TracePartFunction::~TracePartFunction()
@@ -788,7 +788,7 @@
     _callingContexts = 0;
 
     // To calculate context counts, we just use first real event type (FIXME?)
-    EventType* e = data() ? data()->eventTypes()->realType(0) : 0;
+    EventType* e = data() ? data()->eventTypes()->realType(0) : nullptr;
 
     // calculate additional cost metrics
     foreach(TracePartCall* caller, _partCallers) {
@@ -928,7 +928,7 @@
                                bool isCondJump)
     : TraceJumpCost(ProfileContext::context(ProfileContext::InstrJump))
 {
-    _first = 0;
+    _first = nullptr;
 
     _instrFrom = instrFrom;
     _instrTo = instrTo;
@@ -948,7 +948,7 @@
 
 TracePartInstrJump* TraceInstrJump::partInstrJump(TracePart* part)
 {
-    static TracePartInstrJump* item = 0;
+    static TracePartInstrJump* item = nullptr;
 
     // shortcut if recently used
     if (item &&
@@ -1270,7 +1270,7 @@
         TraceFunctionCycle* c = _called->cycle();
         if (c && _caller && (_caller->cycle() != c)) {
             // HACK to get rid of cycle postfix...
-            _called->setCycle(0);
+            _called->setCycle(nullptr);
             QString via = _called->prettyName();
             _called->setCycle(c);
             return QObject::tr("%1 via %2").arg(c->name()).arg(via);
@@ -1287,8 +1287,8 @@
     : TraceListCost(ProfileContext::context(ProfileContext::Instr))
 {
     _addr = 0;
-    _line = 0;
-    _function = 0;
+    _line = nullptr;
+    _function = nullptr;
 }
 
 TraceInstr::~TraceInstr()
@@ -1381,7 +1381,7 @@
     : TraceListCost(ProfileContext::context(ProfileContext::Line))
 {
     _lineno = 0;
-    _sourceFile = 0;
+    _sourceFile = nullptr;
 }
 
 TraceLine::~TraceLine()
@@ -1513,9 +1513,9 @@
     // the function is dependent from our cost sum
     _dep = _function;
 
-    _lineMap = 0;
+    _lineMap = nullptr;
     _lineMapFilled = false;
-    _line0 = 0;
+    _line0 = nullptr;
 }
 
 TraceFunctionSource::~TraceFunctionSource()
@@ -1555,18 +1555,18 @@
 {
     if (lineno == 0) {
         if (!_line0) {
-            if (!createNew) return 0;
+            if (!createNew) return nullptr;
             _line0 = new TraceLine;
             _line0->setSourceFile(this);
             _line0->setLineno(0);
         }
         return _line0;
     }
 
     if (!createNew) {
-        if (!_lineMap) return 0;
+        if (!_lineMap) return nullptr;
         TraceLineMap::Iterator it = _lineMap->find(lineno);
-        if (it == _lineMap->end()) return 0;
+        if (it == _lineMap->end()) return nullptr;
         return &(it.value());
     }
 
@@ -1624,10 +1624,10 @@
     if (!_lineMap)
         _lineMap = new TraceLineMap;
 
-    TraceLine* l = 0;
-    TracePartLine* pl = 0;
-    TraceLineCall* lc = 0;
-    TracePartLineCall* plc = 0;
+    TraceLine* l = nullptr;
+    TracePartLine* pl = nullptr;
+    TraceLineCall* lc = nullptr;
+    TracePartLineCall* plc = nullptr;
 
     /* go over all part objects for this function, and
      * - build TraceLines (the line map) using FixCost objects
@@ -1651,14 +1651,14 @@
                     l->setSourceFile(this);
                     l->setLineno(fc->line());
                 }
-                pl = 0;
+                pl = nullptr;
             }
             if (!pl || pl->part() != fc->part())
                 pl = l->partLine(fc->part(), pf);
             fc->addTo(pl);
         }
 
-        TraceLine* to = 0;
+        TraceLine* to = nullptr;
         TraceLineJump* lj;
         TracePartLineJump* plj;
         FixJump* fj = pf->firstFixJump();
@@ -1710,7 +1710,7 @@
                 }
                 if (!lc || lc->call() != pc->call() || lc->line() != l) {
                     lc = pc->call()->lineCall(l);
-                    plc = 0;
+                    plc = nullptr;
                 }
                 if (!plc || plc->part() != fcc->part())
                     plc = lc->partLineCall(fcc->part(), pc);
@@ -1736,7 +1736,7 @@
 
 TraceAssociation::TraceAssociation()
 {
-    _function = 0;
+    _function = nullptr;
     _valid = false;
 }
 
@@ -1764,7 +1764,7 @@
     }
 
     _function = f;
-    if (f && f->association(rtti()) == 0) {
+    if (f && f->association(rtti()) == nullptr) {
         f->addAssociation(this);
         return true;
     }
@@ -1794,17 +1794,17 @@
 TraceFunction::TraceFunction()
     : TraceCostItem(ProfileContext::context(ProfileContext::Function))
 {
-    _object = 0;
-    _file = 0;
-    _cls = 0;
-    _cycle = 0;
+    _object = nullptr;
+    _file = nullptr;
+    _cls = nullptr;
+    _cycle = nullptr;
 
     _calledCount     = 0;
     _callingCount    = 0;
     _calledContexts  = 0;
     _callingContexts = 0;
 
-    _instrMap = 0;
+    _instrMap = nullptr;
     _instrMapFilled = false;
 }
 
@@ -1865,7 +1865,7 @@
         if (a->rtti() == rtti)
             return a;
     }
-    return 0;
+    return nullptr;
 }
 
 #if 0
@@ -2100,13 +2100,13 @@
 TraceInstr* TraceFunction::instr(Addr addr, bool createNew)
 {
     // address 0 not allowed
-    if (addr == Addr(0)) return 0;
+    if (addr == Addr(0)) return nullptr;
 
     if (!createNew) {
-        if (!_instrMap) return 0;
+        if (!_instrMap) return nullptr;
         TraceInstrMap::Iterator it = _instrMap->find(addr);
         if (it == _instrMap->end())
-            return 0;
+            return nullptr;
         return &(it.value());
     }
 
@@ -2175,7 +2175,7 @@
         if (sourceFile->file() == file)
             return sourceFile;
 
-    if (!createNew) return 0;
+    if (!createNew) return nullptr;
 
     TraceFunctionSource* sourceFile = new TraceFunctionSource(this, file);
     _sourceFiles.append(sourceFile);
@@ -2194,11 +2194,11 @@
 TraceLine* TraceFunction::line(TraceFile* file, uint lineno,
                                bool createNew)
 {
-    Q_ASSERT(file!=0);
+    Q_ASSERT(file!=nullptr);
 
     TraceFunctionSource* sf = sourceFile(file, createNew);
     if (!sf)
-        return 0;
+        return nullptr;
     else
         return sf->line(lineno, createNew);
 }
@@ -2227,7 +2227,7 @@
         if (partObject)
             partObject->addPartFunction(item);
     }
-    else if (item->partObject()==0 && partObject) {
+    else if (item->partObject()==nullptr && partObject) {
         item->setPartObject(partObject);
         partObject->addPartFunction(item);
     }
@@ -2339,7 +2339,7 @@
     clear();
 
     // To calculate context counts, we just use first real event type (FIXME?)
-    EventType* e = data() ? data()->eventTypes()->realType(0) : 0;
+    EventType* e = data() ? data()->eventTypes()->realType(0) : nullptr;
 
     // context count is NOT the sum of part contexts
     foreach(TraceCall *caller, _callers) {
@@ -2411,8 +2411,8 @@
 
 void TraceFunction::cycleReset()
 {
-    _cycle = 0;
-    _cycleStackDown = 0;
+    _cycle = nullptr;
+    _cycleStackDown = nullptr;
     _cycleLow = 0;
 }
 
@@ -2435,7 +2435,7 @@
      * percent of the cost of the function.
      * FIXME: Which cost type to use for this heuristic ?!
      */
-    Q_ASSERT((data() != 0) && (data()->eventTypes()->realCount()>0));
+    Q_ASSERT((data() != nullptr) && (data()->eventTypes()->realCount()>0));
     EventType* e = data()->eventTypes()->realType(0);
 
     SubCost base = 0;
@@ -2494,7 +2494,7 @@
 
         if (*pTop == this) {
             *pTop = _cycleStackDown;
-            _cycleStackDown = 0;
+            _cycleStackDown = nullptr;
         }
         else {
             // a SCC with >1 members
@@ -2508,7 +2508,7 @@
 
                 // remove from stack
                 *pTop = top->_cycleStackDown;
-                top->_cycleStackDown = 0;
+                top->_cycleStackDown = nullptr;
 
                 if (0) qDebug("  %s", qPrintable(top->prettyName()));
                 if (top == this) break;
@@ -2527,11 +2527,11 @@
     if (!_instrMap)
         _instrMap = new TraceInstrMap;
 
-    TraceLine* l = 0;
-    TraceInstr* i = 0;
-    TracePartInstr* pi = 0;
-    TraceInstrCall* ic = 0;
-    TracePartInstrCall* pic = 0;
+    TraceLine* l = nullptr;
+    TraceInstr* i = nullptr;
+    TracePartInstr* pi = nullptr;
+    TraceInstrCall* ic = nullptr;
+    TracePartInstrCall* pic = nullptr;
 
     foreach(TraceInclusiveCost* icost, deps()) {
         TracePartFunction* pf = (TracePartFunction*) icost;
@@ -2555,14 +2555,14 @@
                     i->setAddr(fc->addr());
                     i->setLine(l);
                 }
-                pi = 0;
+                pi = nullptr;
             }
             if (!pi || pi->part() != fc->part())
                 pi = i->partInstr(fc->part(), pf);
             fc->addTo(pi);
         }
 
-        TraceInstr* to = 0;
+        TraceInstr* to = nullptr;
         TraceInstrJump* ij;
         TracePartInstrJump* pij;
         FixJump* fj = pf->firstFixJump();
@@ -2614,7 +2614,7 @@
                 }
                 if (!ic || ic->call() != pc->call() || ic->instr() != i) {
                     ic = pc->call()->instrCall(i);
-                    pic = 0;
+                    pic = nullptr;
                 }
                 if (!pic || pic->part() != fcc->part())
                     pic = ic->partInstrCall(fcc->part(), pc);
@@ -2985,7 +2985,7 @@
     _tid = 0;
     _pid = 0;
 
-    _eventTypeMapping = 0;
+    _eventTypeMapping = nullptr;
 }
 
 TracePart::~TracePart()
@@ -3078,8 +3078,8 @@
 
     _maxThreadID = 0;
     _maxPartNumber = 0;
-    _fixPool = 0;
-    _dynPool = 0;
+    _fixPool = nullptr;
+    _dynPool = nullptr;
 
     _arch = ArchUnknown;
 }
@@ -3207,7 +3207,7 @@
 
     int partsLoaded = l->load(this, device, filename);
 
-    l->setLogger(0);
+    l->setLogger(nullptr);
 
     return partsLoaded;
 }
@@ -3276,7 +3276,7 @@
     foreach(TracePart* part, _parts)
         if (part->name() == name)
             return part;
-    return 0;
+    return nullptr;
 }
 
 QString TraceData::activePartRange()
@@ -3418,7 +3418,7 @@
 
     if (!file || !object || !c) {
         qDebug("ERROR - no file/object/class for %s ?!", qPrintable(name));
-        return 0;
+        return nullptr;
     }
 
     // Use object name and file name as part of key, to get distinct
@@ -3530,7 +3530,7 @@
 ProfileCostArray* TraceData::search(ProfileContext::Type t, QString name,
                                     EventType* ct, ProfileCostArray* parent)
 {
-    ProfileCostArray* result = 0;
+    ProfileCostArray* result = nullptr;
     ProfileContext::Type pt;
     SubCost sc, scTop = 0;
 
@@ -3719,7 +3719,7 @@
         }
 #endif
 
-        stackTop = 0;
+        stackTop = nullptr;
         (*it).cycleDFS(1, pNo, &stackTop);
     }
 
diff --git a/libcore/utils.h b/libcore/utils.h
--- a/libcore/utils.h
+++ b/libcore/utils.h
@@ -39,7 +39,7 @@
 
 public:
     // constructor for an invalid string
-    FixString() { _len = 0; _str = 0; }
+    FixString() { _len = 0; _str = nullptr; }
 
     /**
      * FixString never does a deep copy! You have to make sure that
@@ -51,7 +51,7 @@
     int len() { return _len; }
     const char* ascii() { return _str; }
     bool isEmpty() { return _len == 0; }
-    bool isValid() { return _str != 0; }
+    bool isValid() { return _str != nullptr; }
 
     // sets <c> to first character and returns true if length >0
     bool first(char& c)
diff --git a/libcore/utils.cpp b/libcore/utils.cpp
--- a/libcore/utils.cpp
+++ b/libcore/utils.cpp
@@ -361,7 +361,7 @@
     _openError = false;
     _used_mmap = false;
 
-    uchar* addr = 0;
+    uchar* addr = nullptr;
 
 #if QT_VERSION >= 0x040400
     // QFile::map was introduced with Qt 4.4
diff --git a/libviews/callgraphview.h b/libviews/callgraphview.h
--- a/libviews/callgraphview.h
+++ b/libviews/callgraphview.h
@@ -110,10 +110,10 @@
     void setCaller(GraphEdge*);
     TraceFunction* nextVisible();
     TraceFunction* priorVisible();
-    TraceCall* nextVisibleCaller(GraphEdge* = 0);
-    TraceCall* nextVisibleCallee(GraphEdge* = 0);
-    TraceCall* priorVisibleCaller(GraphEdge* = 0);
-    TraceCall* priorVisibleCallee(GraphEdge* = 0);
+    TraceCall* nextVisibleCaller(GraphEdge* = nullptr);
+    TraceCall* nextVisibleCallee(GraphEdge* = nullptr);
+    TraceCall* priorVisibleCaller(GraphEdge* = nullptr);
+    TraceCall* priorVisibleCallee(GraphEdge* = nullptr);
 
     double self, incl;
 
@@ -258,17 +258,17 @@
 {
 public:
     StorableGraphOptions();
-    virtual ~StorableGraphOptions(){}
+    ~StorableGraphOptions() override{}
     // implementation of getters
-    virtual double funcLimit() { return _funcLimit; }
-    virtual double callLimit() { return _callLimit; }
-    virtual int maxCallerDepth() { return _maxCallerDepth; }
-    virtual int maxCalleeDepth() { return _maxCalleeDepth; }
-    virtual bool showSkipped() { return _showSkipped; }
-    virtual bool expandCycles() { return _expandCycles; }
-    virtual bool clusterGroups() { return _clusterGroups; }
-    virtual int detailLevel() { return _detailLevel; }
-    virtual Layout layout() { return _layout; }
+    double funcLimit() override { return _funcLimit; }
+    double callLimit() override { return _callLimit; }
+    int maxCallerDepth() override { return _maxCallerDepth; }
+    int maxCalleeDepth() override { return _maxCalleeDepth; }
+    bool showSkipped() override { return _showSkipped; }
+    bool expandCycles() override { return _expandCycles; }
+    bool clusterGroups() override { return _clusterGroups; }
+    int detailLevel() override { return _detailLevel; }
+    Layout layout() override { return _layout; }
 
     // setters
     void setMaxCallerDepth(int d) { _maxCallerDepth = d; }
@@ -302,7 +302,7 @@
     GraphExporter(TraceData*, TraceFunction*, EventType*,
                   ProfileContext::Type,
                   QString filename = QString());
-    virtual ~GraphExporter();
+    ~GraphExporter() override;
 
     void reset(TraceData*, CostItem*, EventType*,
                ProfileContext::Type,
@@ -325,13 +325,13 @@
 
     // Set the object from which to get graph options for creation.
     // Default is this object itself (supply 0 for default)
-    void setGraphOptions(GraphOptions* go = 0);
+    void setGraphOptions(GraphOptions* go = nullptr);
 
     // Create a subgraph with given limits/maxDepths
     void createGraph();
 
     // calls createGraph before dumping of not already created
-    void writeDot(QIODevice* = 0);
+    void writeDot(QIODevice* = nullptr);
 
     // to map back to structures when parsing a layouted graph
 
@@ -379,19 +379,19 @@
     Q_OBJECT
 
 public:
-    explicit PanningView(QWidget * parent = 0);
+    explicit PanningView(QWidget * parent = nullptr);
 
     void setZoomRect(const QRectF& r);
 
 signals:
     void zoomRectMoved(qreal dx, qreal dy);
     void zoomRectMoveFinished();
 
 protected:
-    void mousePressEvent(QMouseEvent*);
-    void mouseMoveEvent(QMouseEvent*);
-    void mouseReleaseEvent(QMouseEvent*);
-    void drawForeground(QPainter * p, const QRectF&);
+    void mousePressEvent(QMouseEvent*) override;
+    void mouseMoveEvent(QMouseEvent*) override;
+    void mouseReleaseEvent(QMouseEvent*) override;
+    void drawForeground(QPainter * p, const QRectF&) override;
 
     QRectF _zoomRect;
     bool _movingZoomRect;
@@ -421,14 +421,14 @@
 
     void updateGroup();
     void setSelected(bool);
-    void paint(QPainter*, const QStyleOptionGraphicsItem*, QWidget*);
+    void paint(QPainter*, const QStyleOptionGraphicsItem*, QWidget*) override;
 
     GraphNode* node()
     {
         return _node;
     }
 
-    int type() const
+    int type() const override
     {
         return CANVAS_NODE;
     }
@@ -444,14 +444,14 @@
 public:
     CanvasEdgeLabel(CallGraphView*, CanvasEdge*, int, int, int, int);
 
-    void paint(QPainter*, const QStyleOptionGraphicsItem*, QWidget*);
+    void paint(QPainter*, const QStyleOptionGraphicsItem*, QWidget*) override;
 
     CanvasEdge* canvasEdge()
     {
         return _ce;
     }
 
-    int type() const
+    int type() const override
     {
         return CANVAS_EDGELABEL;
     }
@@ -474,14 +474,14 @@
 public:
     explicit CanvasEdgeArrow(CanvasEdge*);
 
-    void paint(QPainter*, const QStyleOptionGraphicsItem*, QWidget*);
+    void paint(QPainter*, const QStyleOptionGraphicsItem*, QWidget*) override;
 
     CanvasEdge* canvasEdge()
     {
         return _ce;
     }
 
-    int type() const
+    int type() const override
     {
         return CANVAS_EDGEARROW;
     }
@@ -496,7 +496,7 @@
 public:
     explicit CanvasEdge(GraphEdge*);
 
-    void paint(QPainter*, const QStyleOptionGraphicsItem*, QWidget*);
+    void paint(QPainter*, const QStyleOptionGraphicsItem*, QWidget*) override;
 
     void setSelected(bool);
 
@@ -526,7 +526,7 @@
         return _edge;
     }
 
-    int type() const
+    int type() const override
     {
         return CANVAS_EDGE;
     }
@@ -546,7 +546,7 @@
 public:
     explicit CanvasFrame(CanvasNode*);
 
-    int type() const
+    int type() const override
     {
         return CANVAS_FRAME;
     }
@@ -556,7 +556,7 @@
         return false;
     }
 
-    void paint(QPainter*, const QStyleOptionGraphicsItem*, QWidget*);
+    void paint(QPainter*, const QStyleOptionGraphicsItem*, QWidget*) override;
 
 private:
     static QPixmap* _p;
@@ -580,17 +580,17 @@
 
     explicit CallGraphView(TraceItemView* parentView, QWidget* parent,
                            const QString& name);
-    ~CallGraphView();
+    ~CallGraphView() override;
 
-    void restoreOptions(const QString& prefix, const QString& postfix);
-    void saveOptions(const QString& prefix, const QString& postfix);
+    void restoreOptions(const QString& prefix, const QString& postfix) override;
+    void saveOptions(const QString& prefix, const QString& postfix) override;
 
-    QWidget* widget()
+    QWidget* widget() override
     {
         return this;
     }
 
-    QString whatsThis() const;
+    QString whatsThis() const override;
 
     ZoomPosition zoomPos() const
     {
@@ -620,21 +620,21 @@
     void layoutTriggered(QAction*);
 
 protected:
-    void resizeEvent(QResizeEvent*);
-    void mousePressEvent(QMouseEvent*);
-    void mouseMoveEvent(QMouseEvent*);
-    void mouseReleaseEvent(QMouseEvent*);
-    void mouseDoubleClickEvent(QMouseEvent*);
-    void contextMenuEvent(QContextMenuEvent*);
-    void keyPressEvent(QKeyEvent*);
-    void focusInEvent(QFocusEvent*);
-    void focusOutEvent(QFocusEvent*);
-    void scrollContentsBy(int dx, int dy);
+    void resizeEvent(QResizeEvent*) override;
+    void mousePressEvent(QMouseEvent*) override;
+    void mouseMoveEvent(QMouseEvent*) override;
+    void mouseReleaseEvent(QMouseEvent*) override;
+    void mouseDoubleClickEvent(QMouseEvent*) override;
+    void contextMenuEvent(QContextMenuEvent*) override;
+    void keyPressEvent(QKeyEvent*) override;
+    void focusInEvent(QFocusEvent*) override;
+    void focusOutEvent(QFocusEvent*) override;
+    void scrollContentsBy(int dx, int dy) override;
 
 private:
     void updateSizes(QSize s = QSize(0,0));
-    CostItem* canShow(CostItem*);
-    void doUpdate(int, bool);
+    CostItem* canShow(CostItem*) override;
+    void doUpdate(int, bool) override;
     void refresh();
     void makeFrame(CanvasNode*, bool active);
     void clear();
diff --git a/libviews/callgraphview.cpp b/libviews/callgraphview.cpp
--- a/libviews/callgraphview.cpp
+++ b/libviews/callgraphview.cpp
@@ -131,9 +131,9 @@
 
 GraphNode::GraphNode()
 {
-    _f=0;
+    _f=nullptr;
     self = incl = 0;
-    _cn = 0;
+    _cn = nullptr;
 
     _visible = false;
     _lastCallerIndex = _lastCalleeIndex = -1;
@@ -236,10 +236,10 @@
     // can not use at(): index can be -1 (out of bounds), result is 0 then
     GraphEdge* e = callers.value(_lastCallerIndex);
     if (e && !e->isVisible())
-        e = 0;
+        e = nullptr;
     if (!e) {
         double maxCost = 0.0;
-        GraphEdge* maxEdge = 0;
+        GraphEdge* maxEdge = nullptr;
         for(int i = 0; i<callers.size(); i++) {
             e = callers[i];
             if (e->isVisible() && (e->cost > maxCost)) {
@@ -250,7 +250,7 @@
         }
         e = maxEdge;
     }
-    return e ? e->call() : 0;
+    return e ? e->call() : nullptr;
 }
 
 TraceCall* GraphNode::visibleCallee()
@@ -261,11 +261,11 @@
 
     GraphEdge* e = callees.value(_lastCalleeIndex);
     if (e && !e->isVisible())
-        e = 0;
+        e = nullptr;
 
     if (!e) {
         double maxCost = 0.0;
-        GraphEdge* maxEdge = 0;
+        GraphEdge* maxEdge = nullptr;
         for(int i = 0; i<callees.size(); i++) {
             e = callees[i];
             if (e->isVisible() && (e->cost > maxCost)) {
@@ -276,7 +276,7 @@
         }
         e = maxEdge;
     }
-    return e ? e->call() : 0;
+    return e ? e->call() : nullptr;
 }
 
 void GraphNode::setCallee(GraphEdge* e)
@@ -310,7 +310,7 @@
         if (c)
             return c->called(true);
     }
-    return 0;
+    return nullptr;
 }
 
 TraceFunction* GraphNode::priorVisible()
@@ -332,7 +332,7 @@
         if (c)
             return c->called(true);
     }
-    return 0;
+    return nullptr;
 }
 
 TraceCall* GraphNode::nextVisibleCaller(GraphEdge* e)
@@ -346,7 +346,7 @@
         }
         idx++;
     }
-    return 0;
+    return nullptr;
 }
 
 TraceCall* GraphNode::nextVisibleCallee(GraphEdge* e)
@@ -360,7 +360,7 @@
         }
         idx++;
     }
-    return 0;
+    return nullptr;
 }
 
 TraceCall* GraphNode::priorVisibleCaller(GraphEdge* e)
@@ -375,7 +375,7 @@
         }
         idx--;
     }
-    return 0;
+    return nullptr;
 }
 
 TraceCall* GraphNode::priorVisibleCallee(GraphEdge* e)
@@ -390,7 +390,7 @@
         }
         idx--;
     }
-    return 0;
+    return nullptr;
 }
 
 
@@ -400,11 +400,11 @@
 
 GraphEdge::GraphEdge()
 {
-    _c=0;
-    _from = _to = 0;
-    _fromNode = _toNode = 0;
+    _c=nullptr;
+    _from = _to = nullptr;
+    _fromNode = _toNode = nullptr;
     cost = count = 0;
-    _ce = 0;
+    _ce = nullptr;
 
     _visible = false;
     _lastFromCaller = true;
@@ -432,7 +432,7 @@
             _fromNode->setCallee(this);
         return _from;
     }
-    return 0;
+    return nullptr;
 }
 
 TraceFunction* GraphEdge::visibleCallee()
@@ -443,12 +443,12 @@
             _toNode->setCaller(this);
         return _to;
     }
-    return 0;
+    return nullptr;
 }
 
 TraceCall* GraphEdge::nextVisible()
 {
-    TraceCall* res = 0;
+    TraceCall* res = nullptr;
 
     if (_lastFromCaller && _fromNode) {
         res = _fromNode->nextVisibleCallee(this);
@@ -464,7 +464,7 @@
 
 TraceCall* GraphEdge::priorVisible()
 {
-    TraceCall* res = 0;
+    TraceCall* res = nullptr;
 
     if (_lastFromCaller && _fromNode) {
         res = _fromNode->priorVisibleCallee(this);
@@ -530,18 +530,18 @@
 GraphExporter::GraphExporter()
 {
     _go = this;
-    _tmpFile = 0;
-    _item = 0;
-    reset(0, 0, 0, ProfileContext::InvalidType, QString());
+    _tmpFile = nullptr;
+    _item = nullptr;
+    reset(nullptr, nullptr, nullptr, ProfileContext::InvalidType, QString());
 }
 
 GraphExporter::GraphExporter(TraceData* d, TraceFunction* f,
                              EventType* ct, ProfileContext::Type gt,
                              QString filename)
 {
     _go = this;
-    _tmpFile = 0;
-    _item = 0;
+    _tmpFile = nullptr;
+    _item = nullptr;
     reset(d, f, ct, gt, filename);
 }
 
@@ -575,7 +575,7 @@
         case ProfileContext::Call:
             break;
         default:
-            i = 0;
+            i = nullptr;
         }
     }
 
@@ -593,7 +593,7 @@
         _dotName = _tmpFile->fileName();
         _useBox = true;
     } else {
-        _tmpFile = 0;
+        _tmpFile = nullptr;
         _dotName = filename;
         _useBox = false;
     }
@@ -603,7 +603,7 @@
 
 void GraphExporter::setGraphOptions(GraphOptions* go)
 {
-    if (go == 0)
+    if (go == nullptr)
         go = this;
     _go = go;
 }
@@ -663,8 +663,8 @@
     if (!_item)
         return;
 
-    QFile* file = 0;
-    QTextStream* stream = 0;
+    QFile* file = nullptr;
+    QTextStream* stream = nullptr;
 
     if (device)
         stream = new QTextStream(device);
@@ -696,7 +696,7 @@
     if (_go->layout() == LeftRight) {
         *stream << QStringLiteral("  rankdir=LR;\n");
     } else if (_go->layout() == Circular) {
-        TraceFunction *f = 0;
+        TraceFunction *f = nullptr;
         switch (_item->type()) {
         case ProfileContext::Function:
         case ProfileContext::FunctionCycle:
@@ -740,7 +740,7 @@
             g = f->cycle();
             break;
         default:
-            g = 0;
+            g = nullptr;
             break;
         }
         nLists[g].append(&n);
@@ -843,7 +843,7 @@
             countSum = n.callerCountSum();
             if (costSum > _realCallLimit) {
 
-                QPair<TraceFunction*,TraceFunction*> p(0, n.function());
+                QPair<TraceFunction*,TraceFunction*> p(nullptr, n.function());
                 e = &(_edgeMap[p]);
                 e->setCallee(p.second);
                 e->cost = costSum;
@@ -864,7 +864,7 @@
             countSum = n.calleeCountSum();
             if (costSum > _realCallLimit) {
 
-                QPair<TraceFunction*,TraceFunction*> p(n.function(), 0);
+                QPair<TraceFunction*,TraceFunction*> p(n.function(), nullptr);
                 e = &(_edgeMap[p]);
                 e->setCaller(p.first);
                 e->cost = costSum;
@@ -915,32 +915,32 @@
 TraceFunction* GraphExporter::toFunc(QString s)
 {
     if (s[0] != 'F')
-        return 0;
+        return nullptr;
     bool ok;
     TraceFunction* f = (TraceFunction*) s.midRef(1).toULongLong(&ok, 16);
     if (!ok)
-        return 0;
+        return nullptr;
 
     return f;
 }
 
 GraphNode* GraphExporter::node(TraceFunction* f)
 {
     if (!f)
-        return 0;
+        return nullptr;
 
     GraphNodeMap::Iterator it = _nodeMap.find(f);
     if (it == _nodeMap.end())
-        return 0;
+        return nullptr;
 
     return &(*it);
 }
 
 GraphEdge* GraphExporter::edge(TraceFunction* f1, TraceFunction* f2)
 {
     GraphEdgeMap::Iterator it = _edgeMap.find(qMakePair(f1, f2));
     if (it == _edgeMap.end())
-        return 0;
+        return nullptr;
 
     return &(*it);
 }
@@ -964,7 +964,7 @@
 
     double oldIncl = 0.0;
     GraphNode& n = _nodeMap[f];
-    if (n.function() == 0) {
+    if (n.function() == nullptr) {
         n.setFunction(f);
     } else
         oldIncl = n.incl;
@@ -1029,7 +1029,7 @@
         QPair<TraceFunction*,TraceFunction*> p(toCallees ? f : f2,
                                                toCallees ? f2 : f);
         GraphEdge& e = _edgeMap[p];
-        if (e.call() == 0) {
+        if (e.call() == nullptr) {
             e.setCall(call);
             e.setCaller(p.first);
             e.setCallee(p.second);
@@ -1049,7 +1049,7 @@
             QPair<TraceFunction*,TraceFunction*>
                     realP(toCallees ? f : realF, toCallees ? realF : f);
             GraphEdge& e = _edgeMap[realP];
-            if (e.call() == 0) {
+            if (e.call() == nullptr) {
                 e.setCall(call);
                 e.setCaller(realP.first);
                 e.setCallee(realP.second);
@@ -1356,8 +1356,8 @@
 CanvasEdge::CanvasEdge(GraphEdge* e) :
     _edge(e)
 {
-    _label = 0;
-    _arrow = 0;
+    _label = nullptr;
+    _arrow = nullptr;
     _thickness = 0;
 
     setFlag(QGraphicsItem::ItemIsSelectable);
@@ -1435,7 +1435,7 @@
 // CanvasFrame
 //
 
-QPixmap* CanvasFrame::_p = 0;
+QPixmap* CanvasFrame::_p = nullptr;
 
 CanvasFrame::CanvasFrame(CanvasNode* n)
 {
@@ -1512,12 +1512,12 @@
     _zoomPosition = DEFAULT_ZOOMPOS;
     _lastAutoPosition = TopLeft;
 
-    _scene = 0;
+    _scene = nullptr;
     _xMargin = _yMargin = 0;
     _panningView = new PanningView(this);
     _panningZoom = 1;
-    _selectedNode = 0;
-    _selectedEdge = 0;
+    _selectedNode = nullptr;
+    _selectedEdge = nullptr;
     _isMoving = false;
 
     _exporter.setGraphOptions(this);
@@ -1538,8 +1538,8 @@
     // tooltips...
     //_tip = new CallGraphTip(this);
 
-    _renderProcess = 0;
-    _prevSelectedNode = 0;
+    _renderProcess = nullptr;
+    _prevSelectedNode = nullptr;
     connect(&_renderTimer, &QTimer::timeout,
             this, &CallGraphView::showRenderWarning);
 }
@@ -1739,8 +1739,8 @@
                                              ||(e->key() == Qt::Key_Down)||(e->key() == Qt::Key_Left)||(e->key()
                                                                                                         == Qt::Key_Right))) {
 
-        TraceFunction* f = 0;
-        TraceCall* c = 0;
+        TraceFunction* f = nullptr;
+        TraceCall* c = nullptr;
 
         // rotate arrow key meaning for LeftRight layout
         int key = e->key();
@@ -1837,7 +1837,7 @@
             break;
         }
     }
-    return 0;
+    return nullptr;
 }
 
 void CallGraphView::doUpdate(int changeType, bool)
@@ -1853,8 +1853,8 @@
         if (!_selectedItem)
             return;
 
-        GraphNode* n = 0;
-        GraphEdge* e = 0;
+        GraphNode* n = nullptr;
+        GraphEdge* e = nullptr;
         if ((_selectedItem->type() == ProfileContext::Function)
             ||(_selectedItem->type() == ProfileContext::FunctionCycle)) {
             n = _exporter.node((TraceFunction*)_selectedItem);
@@ -1871,14 +1871,14 @@
         if (_selectedNode && _selectedNode->canvasNode()) {
             _selectedNode->canvasNode()->setSelected(false);
         }
-        _selectedNode = 0;
+        _selectedNode = nullptr;
         if (_selectedEdge && _selectedEdge->canvasEdge()) {
             _selectedEdge->canvasEdge()->setSelected(false);
         }
-        _selectedEdge = 0;
+        _selectedEdge = nullptr;
 
         // select
-        CanvasNode* sNode = 0;
+        CanvasNode* sNode = nullptr;
         if (n && n->canvasNode()) {
             _selectedNode = n;
             _selectedNode->canvasNode()->setSelected(true);
@@ -1927,8 +1927,8 @@
     if (changeType & dataChanged) {
         // invalidate old selection and graph part
         _exporter.reset(_data, _activeItem, _eventType, _groupType);
-        _selectedNode = 0;
-        _selectedEdge = 0;
+        _selectedNode = nullptr;
+        _selectedEdge = nullptr;
     }
 
     refresh();
@@ -1939,10 +1939,10 @@
     if (!_scene)
         return;
 
-    _panningView->setScene(0);
-    setScene(0);
+    _panningView->setScene(nullptr);
+    setScene(nullptr);
     delete _scene;
-    _scene = 0;
+    _scene = nullptr;
 }
 
 void CallGraphView::showText(QString s)
@@ -2002,7 +2002,7 @@
 
     // forget about this process, not interesting any longer
     _renderProcess->deleteLater();
-    _renderProcess = 0;
+    _renderProcess = nullptr;
     _unparsedOutput = QString();
 
     _renderTimer.setSingleShot(true);
@@ -2044,8 +2044,8 @@
     if (1)
         qDebug() << "CallGraphView::refresh";
 
-    _selectedNode = 0;
-    _selectedEdge = 0;
+    _selectedNode = nullptr;
+    _selectedEdge = nullptr;
 
     /*
      * Call 'dot' asynchronoulsy in the background with the aim to
@@ -2103,7 +2103,7 @@
     qDebug("CallGraphView::readDotOutput: QProcess %p", p);
 
     // signal from old/uninteresting process?
-    if ((_renderProcess == 0) || (p != _renderProcess)) {
+    if ((_renderProcess == nullptr) || (p != _renderProcess)) {
         p->deleteLater();
         return;
     }
@@ -2118,16 +2118,16 @@
            p->error(), p);
 
     // signal from old/uninteresting process?
-    if ((_renderProcess == 0) || (p != _renderProcess)) {
+    if ((_renderProcess == nullptr) || (p != _renderProcess)) {
         p->deleteLater();
         return;
     }
 
     showRenderError(QString::fromLocal8Bit(_renderProcess->readAllStandardError()));
 
     // not interesting any longer
     _renderProcess->deleteLater();
-    _renderProcess = 0;
+    _renderProcess = nullptr;
 }
 
 
@@ -2137,14 +2137,14 @@
     qDebug("CallGraphView::dotExited: QProcess %p", p);
 
     // signal from old/uninteresting process?
-    if ((_renderProcess == 0) || (p != _renderProcess)) {
+    if ((_renderProcess == nullptr) || (p != _renderProcess)) {
         p->deleteLater();
         return;
     }
 
     _unparsedOutput.append(QString::fromLocal8Bit(_renderProcess->readAllStandardOutput()));
     _renderProcess->deleteLater();
-    _renderProcess = 0;
+    _renderProcess = nullptr;
 
     QString line, cmd;
     CanvasNode *rItem;
@@ -2154,8 +2154,8 @@
     QTextStream* dotStream;
     double scale = 1.0, scaleX = 1.0, scaleY = 1.0;
     double dotWidth = 0, dotHeight = 0;
-    GraphNode* activeNode = 0;
-    GraphEdge* activeEdge = 0;
+    GraphNode* activeNode = nullptr;
+    GraphEdge* activeEdge = nullptr;
 
     _renderTimer.stop();
     viewport()->setUpdatesEnabled(false);
@@ -2248,7 +2248,7 @@
             continue;
         }
 
-        if (_scene == 0) {
+        if (_scene == nullptr) {
             qDebug() << "Ignoring '"<< cmd
                      << "' without 'graph' from dot ("<< _exporter.filename()
                      << ":"<< lineno << ")";
@@ -2369,8 +2369,8 @@
 
         // calls into/out of cycles are special: make them blue
         QColor arrowColor = Qt::black;
-        TraceFunction* caller = e->fromNode() ? e->fromNode()->function() : 0;
-        TraceFunction* called = e->toNode() ? e->toNode()->function() : 0;
+        TraceFunction* caller = e->fromNode() ? e->fromNode()->function() : nullptr;
+        TraceFunction* called = e->toNode() ? e->toNode()->function() : nullptr;
         if ( (caller && (caller->cycle() == caller)) ||
              (called && (called->cycle() == called)) ) arrowColor = Qt::blue;
 
@@ -2395,7 +2395,7 @@
 
         // check if head is at start of spline...
         // this is needed because dot always gives points from top to bottom
-        CanvasNode* fromNode = e->fromNode() ? e->fromNode()->canvasNode() : 0;
+        CanvasNode* fromNode = e->fromNode() ? e->fromNode()->canvasNode() : nullptr;
         if (fromNode) {
             QPointF toCenter = fromNode->rect().center();
             qreal dx0 = poly.point(0).x() - toCenter.x();
@@ -2527,7 +2527,7 @@
         }
     }
 
-    CanvasNode* sNode = 0;
+    CanvasNode* sNode = nullptr;
     if (_selectedNode)
         sNode = _selectedNode->canvasNode();
     else if (_selectedEdge) {
@@ -2566,7 +2566,7 @@
     viewport()->setUpdatesEnabled(true);
 
     delete _renderProcess;
-    _renderProcess = 0;
+    _renderProcess = nullptr;
 }
 
 
@@ -2667,7 +2667,7 @@
 void CallGraphView::mouseDoubleClickEvent(QMouseEvent* e)
 {
     QGraphicsItem* i = itemAt(e->pos());
-    if (i == 0)
+    if (i == nullptr)
         return;
 
     if (i->type() == CANVAS_NODE) {
@@ -2736,7 +2736,7 @@
 
 void CallGraphView::callerDepthTriggered(QAction* a)
 {
-    _maxCallerDepth = a->data().toInt(0);
+    _maxCallerDepth = a->data().toInt(nullptr);
     refresh();
 }
 
@@ -2776,7 +2776,7 @@
 
 void CallGraphView::calleeDepthTriggered(QAction* a)
 {
-    _maxCalleeDepth = a->data().toInt(0);
+    _maxCalleeDepth = a->data().toInt(nullptr);
     refresh();
 }
 
@@ -2819,7 +2819,7 @@
 
 void CallGraphView::nodeLimitTriggered(QAction* a)
 {
-    _funcLimit = a->data().toDouble(0);
+    _funcLimit = a->data().toDouble(nullptr);
     refresh();
 }
 
@@ -2856,7 +2856,7 @@
 
 void CallGraphView::callLimitTriggered(QAction* a)
 {
-    _callLimit = a->data().toDouble(0);
+    _callLimit = a->data().toDouble(nullptr);
     refresh();
 }
 
@@ -2892,7 +2892,7 @@
 
 void CallGraphView::zoomPosTriggered(QAction* a)
 {
-    _zoomPosition = (ZoomPosition) a->data().toInt(0);
+    _zoomPosition = (ZoomPosition) a->data().toInt(nullptr);
     updateSizes();
 }
 
@@ -2925,7 +2925,7 @@
 
 void CallGraphView::layoutTriggered(QAction* a)
 {
-    _layout = (Layout) a->data().toInt(0);
+    _layout = (Layout) a->data().toInt(nullptr);
     refresh();
 }
 
@@ -2937,12 +2937,12 @@
     QGraphicsItem* i = itemAt(e->pos());
 
     QMenu popup;
-    TraceFunction *f = 0, *cycle = 0;
-    TraceCall* c = 0;
+    TraceFunction *f = nullptr, *cycle = nullptr;
+    TraceCall* c = nullptr;
 
-    QAction* activateFunction = 0;
-    QAction* activateCycle = 0;
-    QAction* activateCall = 0;
+    QAction* activateFunction = nullptr;
+    QAction* activateCycle = nullptr;
+    QAction* activateCall = nullptr;
     if (i) {
         if (i->type() == CANVAS_NODE) {
             GraphNode* n = ((CanvasNode*)i)->node();
@@ -2988,7 +2988,7 @@
         }
     }
 
-    QAction* stopLayout = 0;
+    QAction* stopLayout = nullptr;
     if (_renderProcess) {
         stopLayout = popup.addAction(tr("Stop Layouting"));
         popup.addSeparator();
diff --git a/libviews/callitem.h b/libviews/callitem.h
--- a/libviews/callitem.h
+++ b/libviews/callitem.h
@@ -33,7 +33,7 @@
 public:
     CallItem(CallView*, QTreeWidget*, TraceCall* c);
 
-    bool operator<(const QTreeWidgetItem& other) const;
+    bool operator<(const QTreeWidgetItem& other) const override;
     TraceCall* call() { return _call; }
     CallView* view() { return _view; }
     void updateCost();
diff --git a/libviews/callmapview.h b/libviews/callmapview.h
--- a/libviews/callmapview.h
+++ b/libviews/callmapview.h
@@ -41,16 +41,16 @@
     CallMapView(bool showCallers, TraceItemView* parentView,
                 QWidget* parent, const QString& name);
 
-    QWidget* widget() { return this; }
-    QString whatsThis() const;
-    void setData(TraceData*);
+    QWidget* widget() override { return this; }
+    QString whatsThis() const override;
+    void setData(TraceData*) override;
 
-    void restoreOptions(const QString& prefix, const QString& postfix);
-    void saveOptions(const QString& prefix, const QString& postfix);
+    void restoreOptions(const QString& prefix, const QString& postfix) override;
+    void saveOptions(const QString& prefix, const QString& postfix) override;
 
     bool showCallers() const { return _showCallers; }
     ProfileCostArray* totalCost();
-    QString tipString(TreeMapItem*) const;
+    QString tipString(TreeMapItem*) const override;
     QColor groupColor(TraceFunction*) const;
 
 private slots:
@@ -64,8 +64,8 @@
     void borderWidthTriggered(QAction*);
 
 private:
-    CostItem* canShow(CostItem*);
-    void doUpdate(int, bool);
+    CostItem* canShow(CostItem*) override;
+    void doUpdate(int, bool) override;
 
     // context menu builders
     void addItemListMenu(QMenu*,TreeMapItem*);
@@ -94,10 +94,10 @@
 class CallMapItemBase: public TreeMapItem
 {
 public:
-    int maxLines(int) const;
-    bool allowBreak(int) const;
-    bool allowTruncation(int) const;
-    Position position(int) const;
+    int maxLines(int) const override;
+    bool allowBreak(int) const override;
+    bool allowTruncation(int) const override;
+    Position position(int) const override;
 };
 
 class CallMapRootItem: public CallMapItemBase
@@ -107,14 +107,14 @@
 
     void setFunction(TraceFunction* f);
     TraceFunction* function() { return _f; }
-    int rtti() const { return 1; }
-    double sum() const;
-    double value() const;
-    bool isMarked(int) const;
-    QString text(int) const;
-    QPixmap pixmap(int) const;
-    TreeMapItemList* children();
-    QColor backColor() const;
+    int rtti() const override { return 1; }
+    double sum() const override;
+    double value() const override;
+    bool isMarked(int) const override;
+    QString text(int) const override;
+    QPixmap pixmap(int) const override;
+    TreeMapItemList* children() override;
+    QColor backColor() const override;
 
 private:
     TraceFunction* _f;
@@ -126,16 +126,16 @@
 public:
     CallMapCallingItem(double factor, TraceCall* c);
     void init();
-    int rtti() const { return 2; }
-    int borderWidth() const { return widget()->borderWidth(); }
+    int rtti() const override { return 2; }
+    int borderWidth() const override { return widget()->borderWidth(); }
     TraceFunction* function() { return _c->called(); }
-    double value() const;
-    double sum() const;
-    bool isMarked(int) const;
-    QString text(int) const;
-    QPixmap pixmap(int) const;
-    TreeMapItemList* children();
-    QColor backColor() const;
+    double value() const override;
+    double sum() const override;
+    bool isMarked(int) const override;
+    QString text(int) const override;
+    QPixmap pixmap(int) const override;
+    TreeMapItemList* children() override;
+    QColor backColor() const override;
 
 private:
     TraceCall* _c;
@@ -146,15 +146,15 @@
 {
 public:
     CallMapCallerItem(double factor, TraceCall* c);
-    int rtti() const { return 3; }
-    int borderWidth() const { return widget()->borderWidth(); }
+    int rtti() const override { return 3; }
+    int borderWidth() const override { return widget()->borderWidth(); }
     TraceFunction* function() { return _c->caller(); }
-    double value() const;
-    bool isMarked(int) const;
-    QString text(int i) const;
-    QPixmap pixmap(int) const;
-    TreeMapItemList* children();
-    QColor backColor() const;
+    double value() const override;
+    bool isMarked(int) const override;
+    QString text(int i) const override;
+    QPixmap pixmap(int) const override;
+    TreeMapItemList* children() override;
+    QColor backColor() const override;
 
 private:
     TraceCall* _c;
diff --git a/libviews/callmapview.cpp b/libviews/callmapview.cpp
--- a/libviews/callmapview.cpp
+++ b/libviews/callmapview.cpp
@@ -139,7 +139,7 @@
 {
     TraceItemView::setData(d);
 
-    ((CallMapRootItem*)base())->setFunction(0);
+    ((CallMapRootItem*)base())->setFunction(nullptr);
 }
 
 void CallMapView::addItemListMenu(QMenu* menu, TreeMapItem* item)
@@ -440,7 +440,7 @@
             _topLevel->showMessage(msg, 5000);
     }
 
-    TraceFunction* f = 0;
+    TraceFunction* f = nullptr;
 
     if (item->rtti() == 1) {
         CallMapRootItem* bi = (CallMapRootItem*)item;
@@ -472,16 +472,16 @@
     default:
         break;
     }
-    return 0;
+    return nullptr;
 }
 
 void CallMapView::doUpdate(int changeType, bool)
 {
     if (changeType == eventType2Changed) return;
 
     // if there is a selected item, always draw marking...
     if (changeType & selectedItemChanged) {
-        TraceFunction* f = 0;
+        TraceFunction* f = nullptr;
 
         if (_selectedItem) {
             switch(_selectedItem->type()) {
@@ -503,7 +503,7 @@
 
 
     if (changeType & activeItemChanged) {
-        TraceFunction* f = 0;
+        TraceFunction* f = nullptr;
 
         if (_activeItem) {
             switch(_activeItem->type()) {
@@ -573,7 +573,7 @@
 ProfileCostArray* CallMapView::totalCost()
 {
     TraceFunction* f = ((CallMapRootItem*)base())->function();
-    if (!f) return 0;
+    if (!f) return nullptr;
 
     return GlobalConfig::showExpanded() ? f->inclusive() : f->data();
 }
@@ -612,7 +612,7 @@
 
 CallMapRootItem::CallMapRootItem()
 {
-    _f = 0;
+    _f = nullptr;
 }
 
 void CallMapRootItem::setFunction(TraceFunction* f)
diff --git a/libviews/callview.h b/libviews/callview.h
--- a/libviews/callview.h
+++ b/libviews/callview.h
@@ -33,10 +33,10 @@
 
 public:
     CallView(bool showCallers, TraceItemView* parentView,
-             QWidget* parent=0);
+             QWidget* parent=nullptr);
 
-    virtual QWidget* widget() { return this; }
-    QString whatsThis() const;
+    QWidget* widget() override { return this; }
+    QString whatsThis() const override;
     bool showCallers() const { return _showCallers; }
 
 protected slots:
@@ -46,11 +46,11 @@
     void headerClicked(int);
 
 protected:
-    void keyPressEvent(QKeyEvent* event);
+    void keyPressEvent(QKeyEvent* event) override;
 
 private:
-    CostItem* canShow(CostItem*);
-    void doUpdate(int, bool);
+    CostItem* canShow(CostItem*) override;
+    void doUpdate(int, bool) override;
     void refresh();
     void setCostColumnWidths();
 
diff --git a/libviews/callview.cpp b/libviews/callview.cpp
--- a/libviews/callview.cpp
+++ b/libviews/callview.cpp
@@ -115,11 +115,11 @@
     // p is in local coordinates
     int col = columnAt(p.x());
     QTreeWidgetItem* i = itemAt(p);
-    TraceCall* c = i ? ((CallItem*) i)->call() : 0;
-    TraceFunction *f = 0, *cycle = 0;
+    TraceCall* c = i ? ((CallItem*) i)->call() : nullptr;
+    TraceFunction *f = nullptr, *cycle = nullptr;
 
-    QAction* activateFunctionAction = 0;
-    QAction* activateCycleAction = 0;
+    QAction* activateFunctionAction = nullptr;
+    QAction* activateCycleAction = nullptr;
     if (c) {
         QString name  = _showCallers ? c->callerName(true) : c->calledName(true);
         f = _showCallers ? c->caller(true) : c->called(true);
@@ -207,7 +207,7 @@
     default:
         break;
     }
-    return 0;
+    return nullptr;
 }
 
 void CallView::doUpdate(int changeType, bool)
@@ -229,7 +229,7 @@
             if (ti == _selectedItem) return;
         }
 
-        QTreeWidgetItem *item = 0;
+        QTreeWidgetItem *item = nullptr;
         for (int i=0; i<topLevelItemCount();i++) {
             item = topLevelItem(i);
             c = ((CallItem*) item)->call();
@@ -281,7 +281,7 @@
     QList<QTreeWidgetItem*> items;
     foreach(TraceCall* call, l)
         if (call->subCost(_eventType)>0)
-            items.append(new CallItem(this, 0, call));
+            items.append(new CallItem(this, nullptr, call));
 
     // when inserting, switch off sorting for performance reason
     setSortingEnabled(false);
diff --git a/libviews/costlistitem.h b/libviews/costlistitem.h
--- a/libviews/costlistitem.h
+++ b/libviews/costlistitem.h
@@ -32,8 +32,8 @@
     CostListItem(QTreeWidget* parent, int skipped, TraceCostItem* cost,
                  EventType* et);
 
-    bool operator< ( const QTreeWidgetItem & other ) const;
-    TraceCostItem* costItem() { return (_skipped) ? 0 : _costItem; }
+    bool operator< ( const QTreeWidgetItem & other ) const override;
+    TraceCostItem* costItem() { return (_skipped) ? nullptr : _costItem; }
     void setEventType(EventType* et);
     void update();
     void setSize(int s);
diff --git a/libviews/coverageitem.h b/libviews/coverageitem.h
--- a/libviews/coverageitem.h
+++ b/libviews/coverageitem.h
@@ -38,8 +38,8 @@
                        TraceFunction* base,
                        EventType* ct, ProfileContext::Type gt);
 
-    bool operator< ( const QTreeWidgetItem & other ) const;
-    TraceFunction* function() { return (_skipped) ? 0 : _function; }
+    bool operator< ( const QTreeWidgetItem & other ) const override;
+    TraceFunction* function() { return (_skipped) ? nullptr : _function; }
     void setCostType(EventType* ct);
     void setGroupType(ProfileContext::Type);
     void update();
@@ -66,8 +66,8 @@
                        TraceFunction* base,
                        EventType* ct, ProfileContext::Type gt);
 
-    bool operator< ( const QTreeWidgetItem & other ) const;
-    TraceFunction* function() { return (_skipped) ? 0 : _function; }
+    bool operator< ( const QTreeWidgetItem & other ) const override;
+    TraceFunction* function() { return (_skipped) ? nullptr : _function; }
     void setCostType(EventType* ct);
     void setGroupType(ProfileContext::Type);
     void update();
diff --git a/libviews/coverageitem.cpp b/libviews/coverageitem.cpp
--- a/libviews/coverageitem.cpp
+++ b/libviews/coverageitem.cpp
@@ -112,7 +112,7 @@
     }
 
     setText(0, str);
-    setIcon(0, partitionPixmap(25, 10, _coverage->inclusiveHistogram(), 0,
+    setIcon(0, partitionPixmap(25, 10, _coverage->inclusiveHistogram(), nullptr,
                                Coverage::maxHistogramDepth, false));
 
     // call count
@@ -174,7 +174,7 @@
 {
     _skipped = 0;
     _coverage = c;
-    _function = c ? c->function() : 0;
+    _function = c ? c->function() : nullptr;
     _base = base;
     _groupType = ProfileContext::InvalidType;
 
@@ -198,7 +198,7 @@
 {
     _skipped = skipped;
     _coverage = c;
-    _function = c ? c->function() : 0;
+    _function = c ? c->function() : nullptr;
     _base = base;
     _groupType = ProfileContext::InvalidType;
 
@@ -270,9 +270,9 @@
         setText(1, _self.pretty());
     }
 
-    setIcon(0, partitionPixmap(25, 10, _coverage->inclusiveHistogram(), 0,
+    setIcon(0, partitionPixmap(25, 10, _coverage->inclusiveHistogram(), nullptr,
                                Coverage::maxHistogramDepth, false));
-    setIcon(1, partitionPixmap(25, 10, _coverage->selfHistogram(), 0,
+    setIcon(1, partitionPixmap(25, 10, _coverage->selfHistogram(), nullptr,
                                Coverage::maxHistogramDepth, false));
 
 
diff --git a/libviews/coverageview.h b/libviews/coverageview.h
--- a/libviews/coverageview.h
+++ b/libviews/coverageview.h
@@ -35,23 +35,23 @@
 
 public:
     CoverageView(bool showCallers, TraceItemView* parentView,
-                 QWidget* parent = 0);
+                 QWidget* parent = nullptr);
 
-    virtual QWidget* widget() { return this; }
-    QString whatsThis() const;
+    QWidget* widget() override { return this; }
+    QString whatsThis() const override;
 
 protected slots:
     void context(const QPoint &);
     void selectedSlot(QTreeWidgetItem*, QTreeWidgetItem*);
     void activatedSlot(QTreeWidgetItem*, int);
     void headerClicked(int);
 
 protected:
-    void keyPressEvent(QKeyEvent* event);
+    void keyPressEvent(QKeyEvent* event) override;
 
 private:
-    CostItem* canShow(CostItem*);
-    void doUpdate(int, bool);
+    CostItem* canShow(CostItem*) override;
+    void doUpdate(int, bool) override;
     void refresh();
 
     HighestCostList _hc;
diff --git a/libviews/coverageview.cpp b/libviews/coverageview.cpp
--- a/libviews/coverageview.cpp
+++ b/libviews/coverageview.cpp
@@ -158,14 +158,14 @@
     QTreeWidgetItem* i = itemAt(p);
     QMenu popup;
 
-    TraceFunction* f = 0;
+    TraceFunction* f = nullptr;
     if (i) {
         f = _showCallers ?
                 ((CallerCoverageItem*)i)->function() :
                 ((CalleeCoverageItem*)i)->function();
     }
 
-    QAction* activateFunctionAction = 0;
+    QAction* activateFunctionAction = nullptr;
     if (f) {
         QString menuText = tr("Go to '%1'").arg(GlobalConfig::shortenSymbol(f->prettyName()));
         activateFunctionAction = popup.addAction(menuText);
@@ -185,7 +185,7 @@
 
 void CoverageView::selectedSlot(QTreeWidgetItem* i, QTreeWidgetItem*)
 {
-    TraceFunction* f = 0;
+    TraceFunction* f = nullptr;
     if (i) {
         f = _showCallers ?
                 ((CallerCoverageItem*)i)->function() :
@@ -200,7 +200,7 @@
 
 void CoverageView::activatedSlot(QTreeWidgetItem* i, int)
 {
-    TraceFunction* f = 0;
+    TraceFunction* f = nullptr;
     if (i) {
         f = _showCallers ?
                 ((CallerCoverageItem*)i)->function() :
@@ -250,7 +250,7 @@
     default:
         break;
     }
-    return 0;
+    return nullptr;
 }
 
 void CoverageView::doUpdate(int changeType, bool)
@@ -263,7 +263,7 @@
             return;
         }
 
-        TraceFunction* f = 0;
+        TraceFunction* f = nullptr;
         QTreeWidgetItem* i = currentItem();
         if (i) {
             f = _showCallers ?
@@ -309,7 +309,7 @@
     if (!_data || !_activeItem) return;
 
     ProfileContext::Type t = _activeItem->type();
-    TraceFunction* f = 0;
+    TraceFunction* f = nullptr;
     if (t == ProfileContext::Function) f = (TraceFunction*) _activeItem;
     if (t == ProfileContext::FunctionCycle) f = (TraceFunction*) _activeItem;
     if (!f) return;
@@ -338,20 +338,20 @@
         ff = (TraceFunction*) _hc[i];
         Coverage* c = (Coverage*) ff->association(Coverage::Rtti);
         if (_showCallers)
-            item = new CallerCoverageItem(0, c, f, _eventType, _groupType);
+            item = new CallerCoverageItem(nullptr, c, f, _eventType, _groupType);
         else
-            item = new CalleeCoverageItem(0, c, f, _eventType, _groupType);
+            item = new CalleeCoverageItem(nullptr, c, f, _eventType, _groupType);
         items.append(item);
     }
     if (_hc.hasMore()) {
         // a placeholder for all the functions skipped ...
         ff = (TraceFunction*) _hc[_hc.maxSize()-1];
         Coverage* c = (Coverage*) ff->association(Coverage::Rtti);
         if (_showCallers)
-            item = new CallerCoverageItem(0, _hc.count() - _hc.maxSize(),
+            item = new CallerCoverageItem(nullptr, _hc.count() - _hc.maxSize(),
                                           c, f, _eventType, _groupType);
         else
-            item = new CalleeCoverageItem(0, _hc.count() - _hc.maxSize(),
+            item = new CalleeCoverageItem(nullptr, _hc.count() - _hc.maxSize(),
                                           c, f, _eventType, _groupType);
         items.append(item);
     }
diff --git a/libviews/eventtypeitem.h b/libviews/eventtypeitem.h
--- a/libviews/eventtypeitem.h
+++ b/libviews/eventtypeitem.h
@@ -33,13 +33,13 @@
     EventTypeItem(TraceCostItem* costItem,
                   EventType* ct, ProfileContext::Type gt);
 
-    bool operator<(const QTreeWidgetItem &other) const;
+    bool operator<(const QTreeWidgetItem &other) const override;
     void setGroupType(ProfileContext::Type);
     TraceCostItem* costItem() { return _costItem; }
     EventType* eventType() { return _eventType; }
     void update();
 
-    QVariant data(int column, int role) const;
+    QVariant data(int column, int role) const override;
 
 private:
     SubCost _sum, _pure;
diff --git a/libviews/eventtypeitem.cpp b/libviews/eventtypeitem.cpp
--- a/libviews/eventtypeitem.cpp
+++ b/libviews/eventtypeitem.cpp
@@ -70,7 +70,7 @@
 
 void EventTypeItem::update()
 {
-    TraceData* d = _costItem ? _costItem->data() : 0;
+    TraceData* d = _costItem ? _costItem->data() : nullptr;
     double total = d ? ((double)d->subCost(_eventType)) : 0.0;
 
     if (total == 0.0) {
@@ -82,11 +82,11 @@
     }
 
     TraceFunction* f = (_costItem && _costItem->type()==ProfileContext::Function) ?
-                           (TraceFunction*)_costItem : 0;
+                           (TraceFunction*)_costItem : nullptr;
 
     ProfileCostArray* selfTotalCost = f ? f->data() : d;
     if (f && GlobalConfig::showExpanded()) {
-        ProfileCostArray* parent = 0;
+        ProfileCostArray* parent = nullptr;
         switch(_groupType) {
         case ProfileContext::Object:        parent = f->object(); break;
         case ProfileContext::Class:         parent = f->cls(); break;
diff --git a/libviews/eventtypeview.h b/libviews/eventtypeview.h
--- a/libviews/eventtypeview.h
+++ b/libviews/eventtypeview.h
@@ -36,18 +36,18 @@
     explicit EventTypeView(TraceItemView* parentView,
                            QWidget* parent, const QString& name);
 
-    virtual QWidget* widget() { return this; }
-    QString whatsThis() const;
+    QWidget* widget() override { return this; }
+    QString whatsThis() const override;
 
 private slots:
     void context(const QPoint&);
     void currentItemChanged(QTreeWidgetItem*, QTreeWidgetItem*);
     void itemDoubleClicked(QTreeWidgetItem*, int);
     void itemChanged(QTreeWidgetItem*, int);
 
 private:
-    CostItem* canShow(CostItem*);
-    void doUpdate(int, bool);
+    CostItem* canShow(CostItem*) override;
+    void doUpdate(int, bool) override;
     void refresh();
 };
 
diff --git a/libviews/eventtypeview.cpp b/libviews/eventtypeview.cpp
--- a/libviews/eventtypeview.cpp
+++ b/libviews/eventtypeview.cpp
@@ -98,21 +98,21 @@
     QMenu popup;
 
     QTreeWidgetItem* i = itemAt(p);
-    EventType* ct = i ? ((EventTypeItem*) i)->eventType() : 0;
+    EventType* ct = i ? ((EventTypeItem*) i)->eventType() : nullptr;
 
-    QAction* selectType2Action = 0;
-    QAction* hideType2Action = 0;
+    QAction* selectType2Action = nullptr;
+    QAction* hideType2Action = nullptr;
     if (ct)
         selectType2Action = popup.addAction(tr("Set as Secondary Event Type"));
     if (_eventType2)
         hideType2Action = popup.addAction(tr("Hide Secondary Event Type"));
     if (!popup.isEmpty())
         popup.addSeparator();
 
-    QAction* editLongNameAction = 0;
-    QAction* editShortNameAction = 0;
-    QAction* editFormulaAction = 0;
-    QAction* removeTypeAction = 0;
+    QAction* editLongNameAction = nullptr;
+    QAction* editShortNameAction = nullptr;
+    QAction* editFormulaAction = nullptr;
+    QAction* removeTypeAction = nullptr;
     if (ct && !ct->isReal()) {
         editLongNameAction = popup.addAction(tr("Edit Long Name"));
         editShortNameAction = popup.addAction(tr("Edit Short Name"));
@@ -123,22 +123,22 @@
 
     addGoMenu(&popup);
 
-    QAction* newTypeAction = 0;
+    QAction* newTypeAction = nullptr;
     if( _data) {
         popup.addSeparator();
         newTypeAction = popup.addAction(tr("New Event Type..."));
     }
 
     QAction* a = popup.exec(viewport()->mapToGlobal(p));
-    if (a == hideType2Action) selectedEventType2(0);
+    if (a == hideType2Action) selectedEventType2(nullptr);
     else if (a == selectType2Action) selectedEventType2(ct);
     else if (a == editLongNameAction) editItem(i, 0);
     else if (a == editShortNameAction) editItem(i, 3);
     else if (a == editFormulaAction) editItem(i, 5);
     else if (a == removeTypeAction) {
 
         // search for a previous type
-        EventType* prev = 0, *ct = 0;
+        EventType* prev = nullptr, *ct = nullptr;
         EventTypeSet* m = _data->eventTypes();
         for (int i=0;i<m->realCount();i++) {
             ct = m->realType(i);
@@ -183,21 +183,21 @@
 
 void EventTypeView::currentItemChanged(QTreeWidgetItem* i, QTreeWidgetItem*)
 {
-    EventType* ct = i ? ((EventTypeItem*) i)->eventType() : 0;
+    EventType* ct = i ? ((EventTypeItem*) i)->eventType() : nullptr;
     if (ct)
         selectedEventType(ct);
 }
 
 void EventTypeView::itemDoubleClicked(QTreeWidgetItem* i, int)
 {
-    EventType* ct = i ? ((EventTypeItem*) i)->eventType() : 0;
+    EventType* ct = i ? ((EventTypeItem*) i)->eventType() : nullptr;
     if (ct)
         selectedEventType2(ct);
 }
 
 CostItem* EventTypeView::canShow(CostItem* i)
 {
-    if (!i) return 0;
+    if (!i) return nullptr;
 
     switch(i->type()) {
     case ProfileContext::Object:
@@ -208,7 +208,7 @@
     case ProfileContext::Function:
         break;
     default:
-        return 0;
+        return nullptr;
     }
     return i;
 }
@@ -272,9 +272,9 @@
     }
     TraceCostItem* c = (TraceCostItem*) _activeItem;
 
-    EventType* ct =0;
-    QTreeWidgetItem* item = 0;
-    QTreeWidgetItem* selected = 0;
+    EventType* ct =nullptr;
+    QTreeWidgetItem* item = nullptr;
+    QTreeWidgetItem* selected = nullptr;
     QList<QTreeWidgetItem*> items;
 
     EventTypeSet* m = _data->eventTypes();
@@ -304,12 +304,12 @@
 
 void EventTypeView::itemChanged(QTreeWidgetItem* item, int c)
 {
-    EventType* ct = item ? ((EventTypeItem*) item)->eventType() : 0;
+    EventType* ct = item ? ((EventTypeItem*) item)->eventType() : nullptr;
     if (!ct || ct->isReal()) return;
 
     // search for matching known Type
     int knownCount = EventType::knownTypeCount();
-    EventType* known = 0;
+    EventType* known = nullptr;
     for (int i=0; i<knownCount; i++) {
         known = EventType::knownType(i);
         if (known->name() == ct->name()) break;
diff --git a/libviews/functionlistmodel.h b/libviews/functionlistmodel.h
--- a/libviews/functionlistmodel.h
+++ b/libviews/functionlistmodel.h
@@ -34,7 +34,7 @@
 
 public:
     FunctionListModel();
-    ~FunctionListModel();
+    ~FunctionListModel() override;
 
     /* Data to show: all functions from <data>
      * - which are part of function group <group>
@@ -44,16 +44,16 @@
                         EventType* eventType);
 
     // reimplemented from QAbstractItemModel
-    QVariant data(const QModelIndex&, int) const;
-    Qt::ItemFlags flags(const QModelIndex&) const;
+    QVariant data(const QModelIndex&, int) const override;
+    Qt::ItemFlags flags(const QModelIndex&) const override;
     QVariant headerData(int section, Qt::Orientation orientation,
-                        int role = Qt::DisplayRole) const;
+                        int role = Qt::DisplayRole) const override;
     QModelIndex index(int row, int column = 0,
-                      const QModelIndex &parent = QModelIndex()) const;
-    QModelIndex parent(const QModelIndex &index) const;
-    int rowCount(const QModelIndex &parent = QModelIndex()) const;
-    int columnCount(const QModelIndex &parent = QModelIndex()) const;
-    void sort(int column, Qt::SortOrder order);
+                      const QModelIndex &parent = QModelIndex()) const override;
+    QModelIndex parent(const QModelIndex &index) const override;
+    int rowCount(const QModelIndex &parent = QModelIndex()) const override;
+    int columnCount(const QModelIndex &parent = QModelIndex()) const override;
+    void sort(int column, Qt::SortOrder order) override;
 
     void setFilter(QString filter);
     void setEventType(EventType*);
diff --git a/libviews/functionlistmodel.cpp b/libviews/functionlistmodel.cpp
--- a/libviews/functionlistmodel.cpp
+++ b/libviews/functionlistmodel.cpp
@@ -22,7 +22,7 @@
 #include "listutils.h"
 
 FunctionListModel::FunctionListModel()
-    : QAbstractItemModel(0)
+    : QAbstractItemModel(nullptr)
 {
     _maxCount = 300;
     _sortColumn = 0;
@@ -35,7 +35,7 @@
             << tr("Function")
             << tr("Location");
 
-    _max0 = _max1 = _max2 = 0;
+    _max0 = _max1 = _max2 = nullptr;
 }
 
 FunctionListModel::~FunctionListModel()
@@ -58,7 +58,7 @@
 
 TraceFunction* FunctionListModel::function(const QModelIndex& index)
 {
-    if (!index.isValid()) return 0;
+    if (!index.isValid()) return nullptr;
 
     return (TraceFunction*) index.internalPointer();
 }
@@ -77,7 +77,7 @@
     }
 
     TraceFunction *f = (TraceFunction*) index.internalPointer();
-    Q_ASSERT(f != 0);
+    Q_ASSERT(f != nullptr);
     switch(role) {
     case Qt::TextAlignmentRole:
         return (index.column()<3) ? Qt::AlignRight : Qt::AlignLeft;
@@ -120,7 +120,7 @@
 Qt::ItemFlags FunctionListModel::flags(const QModelIndex &index) const
 {
     if (!index.isValid())
-        return 0;
+        return nullptr;
 
     return Qt::ItemIsEnabled | Qt::ItemIsSelectable;
 }
@@ -233,31 +233,31 @@
         case ProfileContext::Object:
         {
             TraceObject* o = dynamic_cast<TraceObject*>(group);
-            Q_ASSERT(o != 0);
+            Q_ASSERT(o != nullptr);
             _list = o->functions();
         }
             break;
 
         case ProfileContext::Class:
         {
             TraceClass* c = dynamic_cast<TraceClass*>(group);
-            Q_ASSERT(c != 0);
+            Q_ASSERT(c != nullptr);
             _list = c->functions();
         }
             break;
 
         case ProfileContext::File:
         {
             TraceFile* f = dynamic_cast<TraceFile*>(group);
-            Q_ASSERT(f != 0);
+            Q_ASSERT(f != nullptr);
             _list = f->functions();
         }
             break;
 
         case ProfileContext::FunctionCycle:
         {
             TraceFunctionCycle* c = dynamic_cast<TraceFunctionCycle*>(group);
-            Q_ASSERT(c != 0);
+            Q_ASSERT(c != nullptr);
             _list = c->members();
         }
             break;
@@ -282,9 +282,9 @@
     FunctionLessThan lessThan2(2, Qt::AscendingOrder, _eventType);
 
     // reset max functions
-    _max0 = 0;
-    _max1 = 0;
-    _max2 = 0;
+    _max0 = nullptr;
+    _max1 = nullptr;
+    _max2 = nullptr;
 
     _filteredList.clear();
     int index = 0;
diff --git a/libviews/functionselection.h b/libviews/functionselection.h
--- a/libviews/functionselection.h
+++ b/libviews/functionselection.h
@@ -48,17 +48,17 @@
     Q_OBJECT
 
 public:
-    explicit FunctionSelection(TopLevelBase*, QWidget* parent = 0);
+    explicit FunctionSelection(TopLevelBase*, QWidget* parent = nullptr);
 
     TraceCostItem* group() { return _group; }
     TraceCostItem* group(QString);
     void setGroup(TraceCostItem*);
     void query(QString);
     bool selectTopFunction();
 
-    QWidget* widget() { return this; }
-    QString whatsThis() const;
-    void setData(TraceData*);
+    QWidget* widget() override { return this; }
+    QString whatsThis() const override;
+    void setData(TraceData*) override;
 
     void updateGroupingMenu(QMenu*);
 
@@ -79,8 +79,8 @@
     void functionHeaderClicked(int);
 
 private:
-    CostItem* canShow(CostItem* i);
-    void doUpdate(int, bool);
+    CostItem* canShow(CostItem* i) override;
+    void doUpdate(int, bool) override;
     void selectFunction();
     void refresh();
     void setCostColumnWidths();
@@ -118,13 +118,13 @@
 {
     Q_OBJECT
 public:
-    explicit AutoToolTipDelegate(QObject* parent = 0);
-    ~AutoToolTipDelegate();
+    explicit AutoToolTipDelegate(QObject* parent = nullptr);
+    ~AutoToolTipDelegate() override;
 
 public slots:
     bool helpEvent( QHelpEvent* e, QAbstractItemView* view,
                     const QStyleOptionViewItem& option,
-                    const QModelIndex& index );
+                    const QModelIndex& index ) override;
 };
 
 #endif
diff --git a/libviews/functionselection.cpp b/libviews/functionselection.cpp
--- a/libviews/functionselection.cpp
+++ b/libviews/functionselection.cpp
@@ -87,9 +87,9 @@
 
 FunctionSelection::FunctionSelection( TopLevelBase* top,
                                       QWidget* parent)
-    : QWidget(parent), TraceItemView(0, top)
+    : QWidget(parent), TraceItemView(nullptr, top)
 {
-    _group = 0;
+    _group = nullptr;
     _inSetGroup = false;
     _inSetFunction = false;
     _functionListSortOrder = Qt::DescendingOrder;
@@ -233,11 +233,11 @@
 {
     TraceItemView::setData(d);
 
-    _group = 0;
+    _group = nullptr;
     _groupSize.clear();
     _hc.clear(GlobalConfig::maxListCount());
     groupList->clear();
-    functionListModel->resetModelData(d, 0, QString(), 0);
+    functionListModel->resetModelData(d, nullptr, QString(), nullptr);
 }
 
 void FunctionSelection::searchReturnPressed()
@@ -250,7 +250,7 @@
         item  = groupList->currentItem();
         if (!item || item->isHidden()) {
             int i;
-            item = 0;
+            item = nullptr;
             for (i=0; i<groupList->topLevelItemCount(); i++) {
                 item = groupList->topLevelItem(i);
                 if (!item->isHidden()) break;
@@ -285,9 +285,9 @@
 void FunctionSelection::functionContext(const QPoint & p)
 {
     QMenu popup;
-    TraceFunction* f = 0;
+    TraceFunction* f = nullptr;
 
-    QAction* activateFunctionAction = 0;
+    QAction* activateFunctionAction = nullptr;
     QModelIndex i = functionList->indexAt(p);
     if (i.isValid()) {
         f = functionListModel->function(i);
@@ -406,7 +406,7 @@
         break;
 
     default:
-        i = 0;
+        i = nullptr;
         break;
     }
     return i;
@@ -468,7 +468,7 @@
     }
 
     if (changeType == activeItemChanged) {
-        if (_activeItem ==0) {
+        if (_activeItem ==nullptr) {
             functionList->clearSelection();
             return;
         }
@@ -536,7 +536,7 @@
             case ProfileContext::File:   _group = f->file();  break;
             case ProfileContext::FunctionCycle: _group = f->cycle();  break;
             default:
-                _group = 0;
+                _group = nullptr;
                 break;
             }
         }
@@ -570,7 +570,7 @@
     if (g == _group) return;
     _group = g;
 
-    QTreeWidgetItem* item = 0;
+    QTreeWidgetItem* item = nullptr;
     int i;
     for (i=0; i < groupList->topLevelItemCount(); i++) {
         item = groupList->topLevelItem(i);
@@ -582,7 +582,7 @@
         groupList->scrollToItem(item);
         // prohibit signalling of a group selection
         _inSetGroup = true;
-        _group = 0;
+        _group = nullptr;
         groupList->setCurrentItem(item);
         _inSetGroup = false;
     }
@@ -603,7 +603,7 @@
     functionListModel->setMaxCount(GlobalConfig::maxListCount());
 
     if (!_data || _data->parts().count()==0) {
-        functionListModel->resetModelData(0, 0, QString(), 0);
+        functionListModel->resetModelData(nullptr, nullptr, QString(), nullptr);
         selectTopFunction();
         return;
     }
@@ -652,7 +652,7 @@
 
     default:
     {
-        _group = 0;
+        _group = nullptr;
         functionListModel->resetModelData(_data, _group, _searchString, _eventType);
         selectFunction(dynamic_cast<TraceFunction*>(_activeItem));
         setCostColumnWidths();
@@ -664,7 +664,7 @@
     if (_activeItem && (_activeItem->type() == _groupType))
         _group = (TraceCostItem*) _activeItem;
 
-    QTreeWidgetItem *item = 0, *activeItem = 0;
+    QTreeWidgetItem *item = nullptr, *activeItem = nullptr;
     QList<QTreeWidgetItem*> items;
 
     // we always put group of active item in list, even if
@@ -708,7 +708,7 @@
     if (activeItem) {
         groupList->scrollToItem(activeItem);
         _inSetGroup = true;
-        _group = 0;
+        _group = nullptr;
         groupList->setCurrentItem(activeItem);
         _inSetGroup = false;
     }
@@ -765,7 +765,7 @@
             return item->costItem();
     }
 
-    return 0;
+    return nullptr;
 }
 
 
@@ -811,7 +811,7 @@
     QRegExp re(query, Qt::CaseInsensitive, QRegExp::Wildcard);
     _groupSize.clear();
 
-    TraceFunction* f = 0;
+    TraceFunction* f = nullptr;
     TraceFunctionList list2;
 
     _hc.clear(GlobalConfig::maxListCount());
@@ -872,7 +872,7 @@
 
     functionActivated(i);
 
-    return (f!=0);
+    return (f!=nullptr);
 }
 
 void FunctionSelection::setCostColumnWidths()
diff --git a/libviews/globalguiconfig.h b/libviews/globalguiconfig.h
--- a/libviews/globalguiconfig.h
+++ b/libviews/globalguiconfig.h
@@ -74,13 +74,13 @@
 
 public:
     GlobalGUIConfig();
-    ~GlobalGUIConfig();
+    ~GlobalGUIConfig() override;
 
     // gets the singleton instance
     static GlobalGUIConfig* config();
 
-    void saveOptions();
-    void readOptions();
+    void saveOptions() override;
+    void readOptions() override;
 
     // color for visualization of an object
     static QColor functionColor(ProfileContext::Type gt, TraceFunction*);
diff --git a/libviews/globalguiconfig.cpp b/libviews/globalguiconfig.cpp
--- a/libviews/globalguiconfig.cpp
+++ b/libviews/globalguiconfig.cpp
@@ -89,13 +89,13 @@
 {
     GlobalGUIConfig* gc;
 
-    if (_config == 0) {
+    if (_config == nullptr) {
         gc = new GlobalGUIConfig();
         _config = gc;
     }
     else {
         gc = dynamic_cast<GlobalGUIConfig*>(_config);
-        if (gc == 0)
+        if (gc == nullptr)
             qFatal("Internal error: config object is not a GlobalGUIConfig.");
     }
 
@@ -231,7 +231,7 @@
 {
     // predefined ?
     GlobalGUIConfig* c = config();
-    ConfigColorSetting* cs = c->_colors.value(n, 0);
+    ConfigColorSetting* cs = c->_colors.value(n, nullptr);
     if (cs || !createNew) return cs;
 
     cs = new ConfigColorSetting(n);
diff --git a/libviews/instritem.h b/libviews/instritem.h
--- a/libviews/instritem.h
+++ b/libviews/instritem.h
@@ -60,7 +60,7 @@
     TraceInstrJump* instrJump() const { return _instrJump; }
     TraceInstrJump* jump(int i) const { return _jump[i]; }
     int jumpCount() const { return _jump.size(); }
-    bool operator< ( const QTreeWidgetItem & other ) const;
+    bool operator< ( const QTreeWidgetItem & other ) const override;
 
     void updateGroup();
     void updateCost();
@@ -88,9 +88,9 @@
 public:
     explicit InstrItemDelegate(InstrView *parent);
     void paint(QPainter *painter, const QStyleOptionViewItem &option,
-               const QModelIndex & index ) const;
+               const QModelIndex & index ) const override;
     QSize sizeHint(const QStyleOptionViewItem &option,
-                   const QModelIndex &index) const;
+                   const QModelIndex &index) const override;
 
 protected:
     void paintArrows(QPainter *p,
diff --git a/libviews/instritem.cpp b/libviews/instritem.cpp
--- a/libviews/instritem.cpp
+++ b/libviews/instritem.cpp
@@ -41,9 +41,9 @@
 {
     _view = iv;
     _addr = addr;
-    _instr = 0;
-    _instrCall = 0;
-    _instrJump = 0;
+    _instr = nullptr;
+    _instrCall = nullptr;
+    _instrJump = nullptr;
     _inside = false;
 
     setTextAlignment(0, Qt::AlignRight);
@@ -67,8 +67,8 @@
     _view = iv;
     _addr = addr;
     _instr = instr;
-    _instrCall = 0;
-    _instrJump = 0;
+    _instrCall = nullptr;
+    _instrJump = nullptr;
     _inside = inside;
 
     setTextAlignment(0, Qt::AlignRight);
@@ -100,7 +100,7 @@
     _addr = addr;
     _instr = instr;
     _instrCall = instrCall;
-    _instrJump = 0;
+    _instrJump = nullptr;
     _inside = true;
 
     setTextAlignment(0, Qt::AlignRight);
@@ -143,7 +143,7 @@
     _addr = addr;
     _inside = true;
     _instr = instr;
-    _instrCall = 0;
+    _instrCall = nullptr;
     _instrJump = instrJump;
 
     setTextAlignment(0, Qt::AlignRight);
@@ -380,7 +380,7 @@
     // draw line borders, detect start/stop of a line
     for(int i=0; i< item->jumpCount(); i++) {
         TraceInstrJump* jump = item->jump(i);
-        if (jump == 0) continue;
+        if (jump == nullptr) continue;
 
         y1 = 0;
         y2 = height;
@@ -455,7 +455,7 @@
     // this overwrites borders of horizontal line
     for(int i=0; i< item->jumpCount(); i++) {
         TraceInstrJump* jump = item->jump(i);
-        if (jump == 0) continue;
+        if (jump == nullptr) continue;
 
         c = jump->isCondJump() ? Qt::red : Qt::blue;
 
diff --git a/libviews/instrview.h b/libviews/instrview.h
--- a/libviews/instrview.h
+++ b/libviews/instrview.h
@@ -37,27 +37,27 @@
 
 public:
     explicit InstrView(TraceItemView* parentView,
-                       QWidget* parent = 0);
+                       QWidget* parent = nullptr);
 
-    virtual QWidget* widget() { return this; }
-    QString whatsThis() const;
+    QWidget* widget() override { return this; }
+    QString whatsThis() const override;
     int arrowLevels() { return _arrowLevels; }
 
-    void restoreOptions(const QString& prefix, const QString& postfix);
-    void saveOptions(const QString& prefix, const QString& postfix);
+    void restoreOptions(const QString& prefix, const QString& postfix) override;
+    void saveOptions(const QString& prefix, const QString& postfix) override;
 
 protected slots:
     void context(const QPoint &);
     void selectedSlot(QTreeWidgetItem*, QTreeWidgetItem*);
     void activatedSlot(QTreeWidgetItem*,int);
     void headerClicked(int);
 
 protected:
-    void keyPressEvent(QKeyEvent* event);
+    void keyPressEvent(QKeyEvent* event) override;
 
 private:
-    CostItem* canShow(CostItem*);
-    void doUpdate(int, bool);
+    CostItem* canShow(CostItem*) override;
+    void doUpdate(int, bool) override;
     void refresh();
     void setColumnWidths();
     bool searchFile(QString&, TraceObject*);
diff --git a/libviews/instrview.cpp b/libviews/instrview.cpp
--- a/libviews/instrview.cpp
+++ b/libviews/instrview.cpp
@@ -254,13 +254,13 @@
     int c = columnAt(p.x());
     QTreeWidgetItem* i = itemAt(p);
 
-    TraceInstrCall* ic = i ? ((InstrItem*) i)->instrCall() : 0;
-    TraceInstrJump* ij = i ? ((InstrItem*) i)->instrJump() : 0;
-    TraceFunction* f = ic ? ic->call()->called() : 0;
-    TraceInstr* instr = ij ? ij->instrTo() : 0;
+    TraceInstrCall* ic = i ? ((InstrItem*) i)->instrCall() : nullptr;
+    TraceInstrJump* ij = i ? ((InstrItem*) i)->instrJump() : nullptr;
+    TraceFunction* f = ic ? ic->call()->called() : nullptr;
+    TraceInstr* instr = ij ? ij->instrTo() : nullptr;
 
-    QAction* activateFunctionAction = 0;
-    QAction* activateInstrAction = 0;
+    QAction* activateFunctionAction = nullptr;
+    QAction* activateInstrAction = nullptr;
     if (f) {
         QString menuText = tr("Go to '%1'").arg(GlobalConfig::shortenSymbol(f->prettyName()));
         activateFunctionAction = popup.addAction(menuText);
@@ -375,7 +375,7 @@
         break;
     }
 
-    return 0;
+    return nullptr;
 }
 
 
@@ -390,15 +390,15 @@
         }
 
         QList<QTreeWidgetItem*> items = selectedItems();
-        InstrItem* ii = (items.count() > 0) ? (InstrItem*)items[0] : 0;
+        InstrItem* ii = (items.count() > 0) ? (InstrItem*)items[0] : nullptr;
         if (ii) {
             if ((ii->instr() == _selectedItem) ||
                 (ii->instr() && (ii->instr()->line() == _selectedItem))) return;
             if (ii->instrCall() &&
                 (ii->instrCall()->call()->called() == _selectedItem)) return;
         }
 
-        TraceInstrJump* ij = 0;
+        TraceInstrJump* ij = nullptr;
         if (_selectedItem->type() == ProfileContext::InstrJump)
             ij = (TraceInstrJump*) _selectedItem;
 
@@ -415,7 +415,7 @@
                 _inSelectionUpdate = false;
                 break;
             }
-            item2 = 0;
+            item2 = nullptr;
             for (int j=0; i<item->childCount(); j++) {
                 item2 = item->child(j);
                 ii = (InstrItem*)item2;
@@ -545,7 +545,7 @@
     if (!_data || !_activeItem) return;
 
     ProfileContext::Type t = _activeItem->type();
-    TraceFunction* f = 0;
+    TraceFunction* f = nullptr;
     if (t == ProfileContext::Function) f = (TraceFunction*) _activeItem;
     if (t == ProfileContext::Instr) {
         f = ((TraceInstr*)_activeItem)->function();
@@ -692,7 +692,7 @@
 
         if (iStart==_arrowLevels) {
             for(iStart=0; iStart<_arrowLevels; ++iStart)
-                if (_jump[iStart] == 0) break;
+                if (_jump[iStart] == nullptr) break;
             if (iStart==_arrowLevels) {
                 _arrowLevels++;
                 _jump.resize(_arrowLevels);
@@ -741,11 +741,11 @@
         if (highAddr > addr)
             break;
         else {
-            if (iEnd>=0) _jump[iEnd] = 0;
+            if (iEnd>=0) _jump[iEnd] = nullptr;
             iEnd = -1;
         }
     }
-    if (iEnd>=0) _jump[iEnd] = 0;
+    if (iEnd>=0) _jump[iEnd] = nullptr;
 }
 
 
@@ -867,7 +867,7 @@
     int objdumpLineno = 0, dumpedLines = 0, noAssLines = 0;
     SubCost most = 0;
     TraceInstr* currInstr;
-    InstrItem *ii, *ii2, *item = 0, *first = 0, *selected = 0;
+    InstrItem *ii, *ii2, *item = nullptr, *first = nullptr, *selected = nullptr;
     QString code, cmd, args;
     bool needObjAddr = true, needCostAddr = true;
 
@@ -944,7 +944,7 @@
                 needCostAddr = true;
             }
             else
-                currInstr = 0;
+                currInstr = nullptr;
 
             needObjAddr = true;
 
@@ -1005,7 +1005,7 @@
             skipLineWritten = false;
 
 
-        ii = new InstrItem(this, 0, addr, inside,
+        ii = new InstrItem(this, nullptr, addr, inside,
                            code, cmd, args, currInstr);
         items.append(ii);
 
diff --git a/libviews/listutils.cpp b/libviews/listutils.cpp
--- a/libviews/listutils.cpp
+++ b/libviews/listutils.cpp
@@ -36,7 +36,7 @@
     static bool inited = false;
 
     if (!inited) {
-        for (int i=0;i<37;i++) pixs[i]=0;
+        for (int i=0;i<37;i++) pixs[i]=nullptr;
         inited = true;
     }
     int hash = (w+h+c.red()+c.green()+c.blue()) % 37;
diff --git a/libviews/multiview.h b/libviews/multiview.h
--- a/libviews/multiview.h
+++ b/libviews/multiview.h
@@ -38,30 +38,30 @@
     Q_OBJECT
 
 public:
-    explicit MultiView(TopLevelBase* top, QWidget* parent = 0);
+    explicit MultiView(TopLevelBase* top, QWidget* parent = nullptr);
 
-    QWidget* widget() { return this; }
+    QWidget* widget() override { return this; }
     TabView* activeTabView() const { return _active; }
-    void setData(TraceData*);
+    void setData(TraceData*) override;
 
     void appendView();
     void removeView();
     void setChildCount(int);
     int childCount() { return _views.count(); }
 
-    void selected(TraceItemView*, CostItem*);
-    void activated(TraceItemView*, CostItem*);
+    void selected(TraceItemView*, CostItem*) override;
+    void activated(TraceItemView*, CostItem*) override;
 
-    void saveLayout(const QString& prefix, const QString& postfix);
-    void restoreLayout(const QString& prefix, const QString& postfix);
-    void saveOptions(const QString& prefix, const QString& postfix);
-    void restoreOptions(const QString& prefix, const QString& postfix);
+    void saveLayout(const QString& prefix, const QString& postfix) override;
+    void restoreLayout(const QString& prefix, const QString& postfix) override;
+    void saveOptions(const QString& prefix, const QString& postfix) override;
+    void restoreOptions(const QString& prefix, const QString& postfix) override;
 
 public slots:
     void tabActivated(TabView*);
 
 private:
-    void doUpdate(int, bool);
+    void doUpdate(int, bool) override;
 
     TabView* _active;
     QList<TabView*> _views;
diff --git a/libviews/multiview.cpp b/libviews/multiview.cpp
--- a/libviews/multiview.cpp
+++ b/libviews/multiview.cpp
@@ -36,7 +36,7 @@
 //
 
 MultiView::MultiView(TopLevelBase* top, QWidget* parent)
-    : QSplitter(parent), TraceItemView(0, top)
+    : QSplitter(parent), TraceItemView(nullptr, top)
 {
     // default
     setOrientation(Qt::Horizontal);
@@ -76,7 +76,7 @@
 
     // set same attributes as in active view
     tv->set(0, _data, _eventType, _eventType2,
-            _groupType, _partList, _activeItem, 0);
+            _groupType, _partList, _activeItem, nullptr);
 
     if (0) qDebug() << "MultiView::appendView, now "
                     << _views.count();
@@ -110,7 +110,7 @@
     if (0) qDebug() << "MultiView::tabActivated "
                     << newActiveTab->objectName();
 
-    CostItem* oldActiveItem = 0;
+    CostItem* oldActiveItem = nullptr;
     if (_active) {
         oldActiveItem = _active->activeItem();
         _active->setActive(false);
@@ -183,7 +183,7 @@
     }
     delete g;
 
-    TabView* activeTV = 0;
+    TabView* activeTV = nullptr;
     foreach(TabView* tv, _views) {
         if (tv->objectName() == active) activeTV=tv;
         tv->restoreLayout( QStringLiteral("%1-%2").arg(prefix).arg(tv->objectName()),
diff --git a/libviews/partgraph.h b/libviews/partgraph.h
--- a/libviews/partgraph.h
+++ b/libviews/partgraph.h
@@ -36,7 +36,7 @@
     // Visualization inside of trace parts
     enum VisualizationMode { NoVisualization, Partitioning, Inclusive };
 
-    explicit PartAreaWidget(QWidget* parent=0);
+    explicit PartAreaWidget(QWidget* parent=nullptr);
 
     void setData(TraceData* d);
     void setEventType(EventType* ct);
@@ -54,7 +54,7 @@
     int callLevels() const { return _callLevels; }
 
     QColor groupColor(TraceFunction*) const;
-    QString tipString(TreeMapItem*) const;
+    QString tipString(TreeMapItem*) const override;
 
     void changeHidden(const TracePartList& list);
     bool isHidden(TracePart*) const;
@@ -80,12 +80,12 @@
 
     void setData(TraceData* d);
 
-    int rtti() const { return 1; }
-    double value() const;
-    QString text(int) const;
-    int borderWidth() const { return 0; }
-    TreeMapItemList* children();
-    QColor backColor() const;
+    int rtti() const override { return 1; }
+    double value() const override;
+    QString text(int) const override;
+    int borderWidth() const override { return 0; }
+    TreeMapItemList* children() override;
+    QColor backColor() const override;
 
 private:
     TraceData* _data;
@@ -95,15 +95,15 @@
 {
 public:
     explicit PartItem(TracePart* p);
-    int rtti() const { return 2; }
+    int rtti() const override { return 2; }
     TracePart* part() { return _p; }
-    double value() const;
-    double sum() const;
-    int borderWidth() const { return 0; }
-    QString text(int) const;
-    QPixmap pixmap(int) const;
-    TreeMapItemList* children();
-    QColor backColor() const;
+    double value() const override;
+    double sum() const override;
+    int borderWidth() const override { return 0; }
+    QString text(int) const override;
+    QPixmap pixmap(int) const override;
+    TreeMapItemList* children() override;
+    QColor backColor() const override;
 
 private:
     TracePart* _p;
@@ -114,15 +114,15 @@
 {
 public:
     explicit SubPartItem(ProfileCostArray*);
-    int rtti() const { return 3; }
+    int rtti() const override { return 3; }
     ProfileCostArray* partCostItem() { return _partCostItem; }
-    double value() const;
-    double sum() const;
-    SplitMode splitMode() const { return Vertical; }
-    QString text(int) const;
-    QPixmap pixmap(int) const;
-    TreeMapItemList* children();
-    QColor backColor() const;
+    double value() const override;
+    double sum() const override;
+    SplitMode splitMode() const override { return Vertical; }
+    QString text(int) const override;
+    QPixmap pixmap(int) const override;
+    TreeMapItemList* children() override;
+    QColor backColor() const override;
 
 private:
     ProfileCostArray* _partCostItem;
diff --git a/libviews/partgraph.cpp b/libviews/partgraph.cpp
--- a/libviews/partgraph.cpp
+++ b/libviews/partgraph.cpp
@@ -33,10 +33,10 @@
 PartAreaWidget::PartAreaWidget(QWidget* parent)
     : TreeMapWidget(new BasePartItem(), parent)
 {
-    _data = 0;
-    _function = 0;
+    _data = nullptr;
+    _function = nullptr;
 
-    _eventType = 0;
+    _eventType = nullptr;
     _groupType = ProfileContext::InvalidType;
     _visualization = NoVisualization;
     _zoomFunction = false;
@@ -48,7 +48,7 @@
     if (data == _data) return;
 
     _data = data;
-    _function = 0;
+    _function = nullptr;
     _hiddenParts.clear();
 
     ((BasePartItem*)base())->setData(data);
@@ -186,7 +186,7 @@
 BasePartItem::BasePartItem()
     : TreeMapItem()
 {
-    _data = 0;
+    _data = nullptr;
     setSorting(-1);
 }
 
@@ -399,7 +399,7 @@
 QColor PartItem::backColor() const
 {
     PartAreaWidget* w = (PartAreaWidget*)widget();
-    return w->groupColor(0);
+    return w->groupColor(nullptr);
 }
 
 
diff --git a/libviews/partlistitem.h b/libviews/partlistitem.h
--- a/libviews/partlistitem.h
+++ b/libviews/partlistitem.h
@@ -36,7 +36,7 @@
     PartListItem(QTreeWidget* parent, TraceCostItem* costItem,
                  EventType* ct, ProfileContext::Type gt, TracePart* part);
 
-    bool operator<(const QTreeWidgetItem& other) const;
+    bool operator<(const QTreeWidgetItem& other) const override;
     ProfileCostArray* partCostItem() { return _partCostItem; }
     void setEventType(EventType* ct);
     void setGroupType(ProfileContext::Type);
diff --git a/libviews/partlistitem.cpp b/libviews/partlistitem.cpp
--- a/libviews/partlistitem.cpp
+++ b/libviews/partlistitem.cpp
@@ -72,9 +72,9 @@
 void PartListItem::update()
 {
     TracePartFunction* pf;
-    pf = !_partCostItem ? 0 :
+    pf = !_partCostItem ? nullptr :
                           (_partCostItem->type()==ProfileContext::PartFunction) ?
-                              ((TracePartFunction*)_partCostItem) : 0;
+                              ((TracePartFunction*)_partCostItem) : nullptr;
 
     double total = _part->subCost(_eventType);
 
diff --git a/libviews/partselection.h b/libviews/partselection.h
--- a/libviews/partselection.h
+++ b/libviews/partselection.h
@@ -40,16 +40,16 @@
     Q_OBJECT
 
 public:
-    explicit PartSelection(TopLevelBase*, QWidget* parent = 0);
+    explicit PartSelection(TopLevelBase*, QWidget* parent = nullptr);
 
-    virtual QWidget* widget() { return this; }
-    QString whatsThis() const;
-    void setData(TraceData*);
+    QWidget* widget() override { return this; }
+    QString whatsThis() const override;
+    void setData(TraceData*) override;
 
     PartAreaWidget* graph() { return _partAreaWidget; }
 
-    void saveOptions(const QString& prefix, const QString& postfix);
-    void restoreOptions(const QString& prefix, const QString& postfix);
+    void saveOptions(const QString& prefix, const QString& postfix) override;
+    void restoreOptions(const QString& prefix, const QString& postfix) override;
 
 signals:
     void partsHideSelected();
@@ -67,8 +67,8 @@
 
 private:
     // reimplementations of TraceItemView
-    CostItem* canShow(CostItem*);
-    void doUpdate(int, bool);
+    CostItem* canShow(CostItem*) override;
+    void doUpdate(int, bool) override;
 
     // helper for doUpdate
     void selectParts(const TracePartList& list);
diff --git a/libviews/partselection.cpp b/libviews/partselection.cpp
--- a/libviews/partselection.cpp
+++ b/libviews/partselection.cpp
@@ -51,7 +51,7 @@
 
 PartSelection::PartSelection( TopLevelBase* top,
                               QWidget* parent)
-    : QWidget(parent), TraceItemView(0, top)
+    : QWidget(parent), TraceItemView(nullptr, top)
 {
     _inSelectionUpdate = false;
 
@@ -145,7 +145,7 @@
     default:
         break;
     }
-    return 0;
+    return nullptr;
 }
 
 /* Helper for doUpdate(), called on partsChanged event.
@@ -201,7 +201,7 @@
         _partAreaWidget->setGroupType(_groupType);
 
     if (changeType & activeItemChanged) {
-        TraceFunction* f = 0;
+        TraceFunction* f = nullptr;
 
         if (_activeItem) {
             switch(_activeItem->type()) {
@@ -252,7 +252,7 @@
     if (!i || i->rtti() != 3) return;
 
     ProfileCostArray* c = ((SubPartItem*) i)->partCostItem();
-    TraceCostItem* ci = 0;
+    TraceCostItem* ci = nullptr;
 
     switch(c->type()) {
     case ProfileContext::PartFunction:
@@ -334,12 +334,12 @@
     QAction* a;
 
     QString str;
-    TreeMapItem* s = 0;
+    TreeMapItem* s = nullptr;
 
-    QAction* selectPartAction = 0;
-    QAction* selectAllPartsAction = 0;
-    QAction* hidePartsAction = 0;
-    QAction* showPartsAction = 0;
+    QAction* selectPartAction = nullptr;
+    QAction* selectAllPartsAction = nullptr;
+    QAction* hidePartsAction = nullptr;
+    QAction* showPartsAction = nullptr;
     if (_data && (_data->parts().count()>1)) {
         s = _partAreaWidget->possibleSelection(i);
         if (!s->text(0).isEmpty()) {
diff --git a/libviews/partview.h b/libviews/partview.h
--- a/libviews/partview.h
+++ b/libviews/partview.h
@@ -33,10 +33,10 @@
     Q_OBJECT
 
 public:
-    explicit PartView(TraceItemView* parentView, QWidget* parent=0);
+    explicit PartView(TraceItemView* parentView, QWidget* parent=nullptr);
 
-    virtual QWidget* widget() { return this; }
-    QString whatsThis() const;
+    QWidget* widget() override { return this; }
+    QString whatsThis() const override;
 
     void refresh();
 
@@ -46,8 +46,8 @@
     void headerClicked(int);
 
 private:
-    CostItem* canShow(CostItem*);
-    void doUpdate(int, bool);
+    CostItem* canShow(CostItem*) override;
+    void doUpdate(int, bool) override;
 
     bool _inSelectionUpdate;
 };
diff --git a/libviews/partview.cpp b/libviews/partview.cpp
--- a/libviews/partview.cpp
+++ b/libviews/partview.cpp
@@ -137,9 +137,9 @@
 
 CostItem* PartView::canShow(CostItem* i)
 {
-    if (!TraceItemView::data()) return 0;
+    if (!TraceItemView::data()) return nullptr;
     if (TraceItemView::data()->parts().count()>1) return i;
-    return 0;
+    return nullptr;
 }
 
 void PartView::doUpdate(int changeType, bool)
@@ -220,7 +220,7 @@
     }
 
     ProfileContext::Type t = _activeItem->type();
-    TraceFunction* f = 0;
+    TraceFunction* f = nullptr;
     if (t == ProfileContext::Function) f = (TraceFunction*) _activeItem;
     if (!f) return;
 
@@ -235,7 +235,7 @@
     QTreeWidgetItem* item;
     foreach(TracePart* part, _data->parts()) {
         if (hidden.contains(part)) continue;
-        item = new PartListItem(0, f, _eventType, _groupType, part);
+        item = new PartListItem(nullptr, f, _eventType, _groupType, part);
         items.append(item);
     }
     setSortingEnabled(false);
diff --git a/libviews/sourceitem.h b/libviews/sourceitem.h
--- a/libviews/sourceitem.h
+++ b/libviews/sourceitem.h
@@ -37,7 +37,7 @@
     SourceItem(SourceView* sv, QTreeWidget* parent,
                int fileno, unsigned int lineno,
                bool inside, const QString& src,
-               TraceLine* line = 0);
+               TraceLine* line = nullptr);
 
     // for call lines
     SourceItem(SourceView* sv, QTreeWidgetItem* parent,
@@ -57,7 +57,7 @@
     TraceLineJump* lineJump() const { return _lineJump; }
     TraceLineJump* jump(int i) const { return _jump[i]; }
     int jumpCount() const { return _jump.size(); }
-    bool operator< ( const QTreeWidgetItem & other ) const;
+    bool operator< ( const QTreeWidgetItem & other ) const override;
 
     void updateGroup();
     void updateCost();
@@ -87,12 +87,12 @@
 public:
     explicit SourceItemDelegate(SourceView *parent);
     void paint(QPainter *painter, const QStyleOptionViewItem &option,
-               const QModelIndex & index ) const;
+               const QModelIndex & index ) const override;
     QSize sizeHint(const QStyleOptionViewItem &option,
-                   const QModelIndex &index) const;
+                   const QModelIndex &index) const override;
     QWidget* createEditor(QWidget *parent,
                           const QStyleOptionViewItem &option,
-                          const QModelIndex &index) const;
+                          const QModelIndex &index) const override;
 
 protected:
     void paintArrows(QPainter *p,
diff --git a/libviews/sourceitem.cpp b/libviews/sourceitem.cpp
--- a/libviews/sourceitem.cpp
+++ b/libviews/sourceitem.cpp
@@ -50,8 +50,8 @@
     _fileno = fileno;
     _inside = inside;
     _line = line;
-    _lineCall = 0;
-    _lineJump = 0;
+    _lineCall = nullptr;
+    _lineJump = nullptr;
 
     setTextAlignment(0, Qt::AlignRight);
     setTextAlignment(1, Qt::AlignRight);
@@ -84,7 +84,7 @@
     _inside = true;
     _line = line;
     _lineCall = lineCall;
-    _lineJump = 0;
+    _lineJump = nullptr;
 
     setTextAlignment(0, Qt::AlignRight);
     setTextAlignment(1, Qt::AlignRight);
@@ -126,7 +126,7 @@
     _fileno = fileno;
     _inside = true;
     _line = line;
-    _lineCall = 0;
+    _lineCall = nullptr;
     _lineJump = lineJump;
 
     setTextAlignment(0, Qt::AlignRight);
@@ -384,7 +384,7 @@
     // draw line borders, detect start/stop of a line
     for(int i=0; i< item->jumpCount(); i++) {
         TraceLineJump* jump = item->jump(i);
-        if (jump == 0) continue;
+        if (jump == nullptr) continue;
 
         y1 = 0;
         y2 = height;
@@ -459,7 +459,7 @@
     // this overwrites borders of horizontal line
     for(int i=0;i< item->jumpCount();i++) {
         TraceLineJump* jump = item->jump(i);
-        if (jump == 0) continue;
+        if (jump == nullptr) continue;
 
         c = jump->isCondJump() ? Qt::red : Qt::blue;
 
diff --git a/libviews/sourceview.h b/libviews/sourceview.h
--- a/libviews/sourceview.h
+++ b/libviews/sourceview.h
@@ -36,10 +36,10 @@
 
 public:
     explicit SourceView(TraceItemView* parentView,
-                        QWidget* parent = 0);
+                        QWidget* parent = nullptr);
 
-    QWidget* widget() { return this; }
-    QString whatsThis() const;
+    QWidget* widget() override { return this; }
+    QString whatsThis() const override;
     int arrowLevels() { return _arrowLevels; }
 
 protected slots:
@@ -49,11 +49,11 @@
     void headerClicked(int);
 
 protected:
-    void keyPressEvent(QKeyEvent* event);
+    void keyPressEvent(QKeyEvent* event) override;
 
 private:
-    CostItem* canShow(CostItem*);
-    void doUpdate(int, bool);
+    CostItem* canShow(CostItem*) override;
+    void doUpdate(int, bool) override;
     void refresh();
     void updateJumpArray(uint,SourceItem*,bool,bool);
     bool searchFile(QString&, TraceFunctionSource*);
diff --git a/libviews/sourceview.cpp b/libviews/sourceview.cpp
--- a/libviews/sourceview.cpp
+++ b/libviews/sourceview.cpp
@@ -109,13 +109,13 @@
     QTreeWidgetItem* i = itemAt(p);
     QMenu popup;
 
-    TraceLineCall* lc = i ? ((SourceItem*) i)->lineCall() : 0;
-    TraceLineJump* lj = i ? ((SourceItem*) i)->lineJump() : 0;
-    TraceFunction* f = lc ? lc->call()->called() : 0;
-    TraceLine* line = lj ? lj->lineTo() : 0;
+    TraceLineCall* lc = i ? ((SourceItem*) i)->lineCall() : nullptr;
+    TraceLineJump* lj = i ? ((SourceItem*) i)->lineJump() : nullptr;
+    TraceFunction* f = lc ? lc->call()->called() : nullptr;
+    TraceLine* line = lj ? lj->lineTo() : nullptr;
 
-    QAction* activateFunctionAction = 0;
-    QAction* activateLineAction = 0;
+    QAction* activateFunctionAction = nullptr;
+    QAction* activateLineAction = nullptr;
     if (f) {
         QString menuText = tr("Go to '%1'").arg(GlobalConfig::shortenSymbol(f->prettyName()));
         activateFunctionAction = popup.addAction(menuText);
@@ -159,13 +159,13 @@
         return;
     }
 
-    TraceFunction* f = lc ? lc->call()->called() : 0;
+    TraceFunction* f = lc ? lc->call()->called() : nullptr;
     if (f) {
         _selectedItem = f;
         selected(f);
     }
     else {
-        TraceLine* line = lj ? lj->lineTo() : 0;
+        TraceLine* line = lj ? lj->lineTo() : nullptr;
         if (line) {
             _selectedItem = line;
             selected(line);
@@ -186,10 +186,10 @@
         return;
     }
 
-    TraceFunction* f = lc ? lc->call()->called() : 0;
+    TraceFunction* f = lc ? lc->call()->called() : nullptr;
     if (f) TraceItemView::activated(f);
     else {
-        TraceLine* line = lj ? lj->lineTo() : 0;
+        TraceLine* line = lj ? lj->lineTo() : nullptr;
         if (line) TraceItemView::activated(line);
     }
 }
@@ -219,7 +219,7 @@
         break;
     }
 
-    return 0;
+    return nullptr;
 }
 
 void SourceView::doUpdate(int changeType, bool)
@@ -232,16 +232,16 @@
             return;
         }
 
-        TraceLine* sLine = 0;
+        TraceLine* sLine = nullptr;
         if (_selectedItem->type() == ProfileContext::Line)
             sLine = (TraceLine*) _selectedItem;
         if (_selectedItem->type() == ProfileContext::Instr)
             sLine = ((TraceInstr*)_selectedItem)->line();
-        if ((_selectedItem->type() != ProfileContext::Function) && (sLine == 0))
+        if ((_selectedItem->type() != ProfileContext::Function) && (sLine == nullptr))
             return;
 
         QList<QTreeWidgetItem*> items = selectedItems();
-        SourceItem* si = (items.count() > 0) ? (SourceItem*)items[0] : 0;
+        SourceItem* si = (items.count() > 0) ? (SourceItem*)items[0] : nullptr;
         if (si) {
             if (sLine && (si->line() == sLine)) return;
             if (si->lineCall() &&
@@ -317,7 +317,7 @@
     }
 
     ProfileContext::Type t = _activeItem->type();
-    TraceFunction* f = 0;
+    TraceFunction* f = nullptr;
     if (t == ProfileContext::Function) f = (TraceFunction*) _activeItem;
     if (t == ProfileContext::Instr) {
         f = ((TraceInstr*)_activeItem)->function();
@@ -471,7 +471,7 @@
 
         if (iStart == asize) {
             for(iStart=0; iStart<asize; ++iStart)
-                if (_jump[iStart] == 0) break;
+                if (_jump[iStart] == nullptr) break;
 
             if (iStart== asize) {
                 asize++;
@@ -524,11 +524,11 @@
         if (highLineno > lineno)
             break;
         else {
-            if (iEnd>=0) _jump[iEnd] = 0;
+            if (iEnd>=0) _jump[iEnd] = nullptr;
             iEnd = -1;
         }
     }
-    if (iEnd>=0) _jump[iEnd] = 0;
+    if (iEnd>=0) _jump[iEnd] = nullptr;
 }
 
 
@@ -593,7 +593,7 @@
 
     bool validSourceFile = (!sf->file()->name().isEmpty());
 
-    TraceLine* sLine = 0;
+    TraceLine* sLine = nullptr;
     if (_selectedItem) {
         if (_selectedItem->type() == ProfileContext::Line)
             sLine = (TraceLine*) _selectedItem;
@@ -740,7 +740,7 @@
 
     QList<QTreeWidgetItem*> items;
     TraceLine* currLine;
-    SourceItem *si, *si2, *item = 0, *first = 0, *selected = 0;
+    SourceItem *si, *si2, *item = nullptr, *first = nullptr, *selected = nullptr;
     QFile file(filename);
     bool fileEndReached = false;
     if (!file.open(QIODevice::ReadOnly)) return;
@@ -794,7 +794,7 @@
             nextCostLineno = (lineIt == lineItEnd) ? 0 : (*lineIt).lineno();
         }
         else
-            currLine = 0;
+            currLine = nullptr;
 
         // update inside
         if (!inside) {
@@ -827,7 +827,7 @@
         QString s = QString(buf);
         if(s.size() > 0 && s.at(s.length()-1) == '\r')
             s = s.left(s.length()-1);
-        si = new SourceItem(this, 0,
+        si = new SourceItem(this, nullptr,
                             fileno, fileLineno, inside, s,
                             currLine);
         items.append(si);
diff --git a/libviews/stackitem.cpp b/libviews/stackitem.cpp
--- a/libviews/stackitem.cpp
+++ b/libviews/stackitem.cpp
@@ -37,7 +37,7 @@
 {
     _view = ss;
     _function = f;
-    _call = 0;
+    _call = nullptr;
 
     setTextAlignment(0, Qt::AlignRight);
     setTextAlignment(1, Qt::AlignRight);
diff --git a/libviews/stackselection.h b/libviews/stackselection.h
--- a/libviews/stackselection.h
+++ b/libviews/stackselection.h
@@ -40,8 +40,8 @@
     Q_OBJECT
 
 public:
-    explicit StackSelection(QWidget* parent = 0);
-    ~StackSelection();
+    explicit StackSelection(QWidget* parent = nullptr);
+    ~StackSelection() override;
 
     TraceData* data() const { return _data; }
     void setData(TraceData*);
diff --git a/libviews/stackselection.cpp b/libviews/stackselection.cpp
--- a/libviews/stackselection.cpp
+++ b/libviews/stackselection.cpp
@@ -36,11 +36,11 @@
 StackSelection::StackSelection(QWidget* parent)
     : QWidget(parent)
 {
-    _data = 0;
+    _data = nullptr;
     _browser = new StackBrowser();
-    _function = 0;
-    _eventType = 0;
-    _eventType2 = 0;
+    _function = nullptr;
+    _eventType = nullptr;
+    _eventType2 = nullptr;
     _groupType = ProfileContext::Function;
 
     setWindowTitle(tr("Stack Selection"));
@@ -85,7 +85,7 @@
     _stackList->clear();
     delete _browser;
     _browser = new StackBrowser();
-    _function = 0;
+    _function = nullptr;
 }
 
 
@@ -120,15 +120,15 @@
 
 
     QList<QTreeWidgetItem*> items;
-    QTreeWidgetItem* activeItem = 0;
+    QTreeWidgetItem* activeItem = nullptr;
     TraceCallList l = item->stack()->calls();
     for(int i=l.count()-1; i>=0; i--) {
-        StackItem* si = new StackItem(this, 0, l.at(i));
+        StackItem* si = new StackItem(this, nullptr, l.at(i));
         if (si->function() == item->function())
             activeItem = si;
         items.prepend(si);
     }
-    StackItem* si = new StackItem(this, 0, top);
+    StackItem* si = new StackItem(this, nullptr, top);
     if (si->function() == item->function())
         activeItem = si;
     items.prepend(si);
diff --git a/libviews/tabview.h b/libviews/tabview.h
--- a/libviews/tabview.h
+++ b/libviews/tabview.h
@@ -51,7 +51,7 @@
 public:
     TabBar(TabView*, QTabWidget* parent);
 protected:
-    void mousePressEvent(QMouseEvent *e);
+    void mousePressEvent(QMouseEvent *e) override;
 
 private:
     void context(QWidget*, const QPoint &);
@@ -72,11 +72,11 @@
     Q_OBJECT
 
 public:
-    explicit Splitter(Qt::Orientation o, QWidget* parent = 0);
+    explicit Splitter(Qt::Orientation o, QWidget* parent = nullptr);
     void checkVisiblity();
 
 protected:
-    void moveEvent(QMoveEvent *);
+    void moveEvent(QMoveEvent *) override;
 };
 
 
@@ -92,19 +92,19 @@
 
 public:
 
-    explicit TabWidget(TabView*, QWidget* parent = 0);
+    explicit TabWidget(TabView*, QWidget* parent = nullptr);
 
     bool hasVisibleRect() { return _hasVisibleRect; }
     void checkVisibility();
 
 signals:
     void visibleRectChanged(TabWidget*);
 
 protected:
-    void resizeEvent(QResizeEvent *);
-    void showEvent(QShowEvent *);
-    void hideEvent(QHideEvent *);
-    void moveEvent(QMoveEvent *);
+    void resizeEvent(QResizeEvent *) override;
+    void showEvent(QShowEvent *) override;
+    void hideEvent(QHideEvent *) override;
+    void moveEvent(QMoveEvent *) override;
 
 private:
     bool _hasVisibleRect;
@@ -119,13 +119,13 @@
 public:
 
     explicit TabView( TraceItemView* parentView,
-                      QWidget* parent = 0 );
+                      QWidget* parent = nullptr );
 
-    virtual QWidget* widget() { return this; }
-    QString whatsThis() const;
-    void setData(TraceData*);
-    bool isViewVisible() { return !_isCollapsed; }
-    void selected(TraceItemView*, CostItem*);
+    QWidget* widget() override { return this; }
+    QString whatsThis() const override;
+    void setData(TraceData*) override;
+    bool isViewVisible() override { return !_isCollapsed; }
+    void selected(TraceItemView*, CostItem*) override;
     bool active() const { return _active; }
     void setActive(bool);
 
@@ -139,10 +139,10 @@
     int visibleTabs();
     int visibleAreas();
 
-    void saveLayout(const QString& prefix, const QString& postfix);
-    void restoreLayout(const QString& prefix, const QString& postfix);
-    void saveOptions(const QString& prefix, const QString& postfix);
-    void restoreOptions(const QString& prefix, const QString& postfix);
+    void saveLayout(const QString& prefix, const QString& postfix) override;
+    void restoreLayout(const QString& prefix, const QString& postfix) override;
+    void saveOptions(const QString& prefix, const QString& postfix) override;
+    void restoreOptions(const QString& prefix, const QString& postfix) override;
 
 public slots:
     void tabChanged(int);
@@ -152,17 +152,17 @@
     void tabActivated(TabView*);
 
 protected:
-    void resizeEvent(QResizeEvent *);
-    bool eventFilter(QObject*, QEvent*);
-    void mousePressEvent(QMouseEvent*);
+    void resizeEvent(QResizeEvent *) override;
+    bool eventFilter(QObject*, QEvent*) override;
+    void mousePressEvent(QMouseEvent*) override;
 
 private:
     TraceItemView* addTab(const QString&, TraceItemView*);
     void addTop(TraceItemView*);
     void addBottom(TraceItemView*);
     TabWidget* tabWidget(Position);
     void updateVisibility();
-    void doUpdate(int, bool);
+    void doUpdate(int, bool) override;
     void updateNameLabel(const QString &n = QString());
     void installFocusFilters();
     void tabCounts(int&, int&, int&, int&);
diff --git a/libviews/tabview.cpp b/libviews/tabview.cpp
--- a/libviews/tabview.cpp
+++ b/libviews/tabview.cpp
@@ -78,7 +78,7 @@
 {
     if (e->button() == Qt::RightButton) {
         int idx = tabAt(e->pos());
-        QWidget* page = 0;
+        QWidget* page = nullptr;
         if (idx >=0) {
             setCurrentIndex(idx);
             page = _tabWidget->widget(idx);
@@ -92,20 +92,20 @@
 {
     QMenu popup, popup2, popup3;
 
-    QAction* pageToTopAction = 0;
-    QAction* areaToTopAction = 0;
-    QAction* showOnTopAction = 0;
-    QAction* pageToRightAction = 0;
-    QAction* areaToRightAction = 0;
-    QAction* showOnRightAction = 0;
-    QAction* pageToBottomAction = 0;
-    QAction* areaToBottomAction = 0;
-    QAction* showOnBottomAction = 0;
-    QAction* pageToLeftAction = 0;
-    QAction* areaToLeftAction = 0;
-    QAction* showOnLeftAction = 0;
-    QAction* hidePageAction = 0;
-    QAction* hideAreaAction = 0;
+    QAction* pageToTopAction = nullptr;
+    QAction* areaToTopAction = nullptr;
+    QAction* showOnTopAction = nullptr;
+    QAction* pageToRightAction = nullptr;
+    QAction* areaToRightAction = nullptr;
+    QAction* showOnRightAction = nullptr;
+    QAction* pageToBottomAction = nullptr;
+    QAction* areaToBottomAction = nullptr;
+    QAction* showOnBottomAction = nullptr;
+    QAction* pageToLeftAction = nullptr;
+    QAction* areaToLeftAction = nullptr;
+    QAction* showOnLeftAction = nullptr;
+    QAction* hidePageAction = nullptr;
+    QAction* hideAreaAction = nullptr;
 
     if (page) {
         TraceItemView::Position p = _tabView->tabPosition(page);
@@ -170,13 +170,13 @@
         _tabView->moveTab(page, TraceItemView::Left, true);
 
     else if (a == showOnTopAction)
-        _tabView->moveTab(0, TraceItemView::Top, true);
+        _tabView->moveTab(nullptr, TraceItemView::Top, true);
     else if (a == showOnRightAction)
-        _tabView->moveTab(0, TraceItemView::Right, true);
+        _tabView->moveTab(nullptr, TraceItemView::Right, true);
     else if (a == showOnBottomAction)
-        _tabView->moveTab(0, TraceItemView::Bottom, true);
+        _tabView->moveTab(nullptr, TraceItemView::Bottom, true);
     else if (a == showOnLeftAction)
-        _tabView->moveTab(0, TraceItemView::Left, true);
+        _tabView->moveTab(nullptr, TraceItemView::Left, true);
 }
 
 
@@ -378,28 +378,28 @@
     // Keep following order in sync with DEFAULT_xxxTABS defines!
 
     addTop( addTab( tr("Types"),
-                    new EventTypeView(this, 0,
+                    new EventTypeView(this, nullptr,
                                       "EventTypeView")));
     addTop( addTab( tr("Callers"), callerView) );
     addTop( addTab( tr("All Callers"), allCallerView) );
     addTop( addTab( tr("Callee Map"),
-                    new CallMapView(false, this, 0,
+                    new CallMapView(false, this, nullptr,
                                     "CalleeMapView")));
     addTop( addTab( tr("Source Code"), sourceView) );
 
     addBottom( addTab( tr("Parts"), partView ) );
     addBottom( addTab( tr("Callees"), calleeView) );
     addBottom( addTab( tr("Call Graph"),
-                       new CallGraphView(this, 0,
+                       new CallGraphView(this, nullptr,
                                          "CallGraphView")));
     addBottom( addTab( tr("All Callees"), allCalleeView) );
     addBottom( addTab( tr("Caller Map"),
-                       new CallMapView(true, this, 0,
+                       new CallMapView(true, this, nullptr,
                                        "CallerMapView")));
     addBottom( addTab( tr("Machine Code"), instrView) );
 
     // after all child widgets are created...
-    _lastFocus = 0;
+    _lastFocus = nullptr;
     _active = false;
     installFocusFilters();
 
@@ -593,14 +593,14 @@
     default:
         break;
     }
-    return 0;
+    return nullptr;
 }
 
 void TabView::moveTab(QWidget* w, Position p, bool wholeArea)
 {
     Position origPos = Hidden;
     if (w) {
-        TraceItemView* found = 0;
+        TraceItemView* found = nullptr;
         foreach(TraceItemView* v, _tabs)
             if (v->widget() == w) { found = v; break; }
 
@@ -627,7 +627,7 @@
             isEnabled = from->isTabEnabled(from->indexOf(w));
             from->removeTab(from->indexOf(w));
         }
-        else isEnabled = (v->canShow(_activeItem)!=0);
+        else isEnabled = (v->canShow(_activeItem)!=nullptr);
 
         if (to) {
             int idx = -1, i;
@@ -691,8 +691,8 @@
 bool TabView::eventFilter(QObject* o, QEvent* e)
 {
     if (e->type() == QEvent::FocusIn) {
-        _lastFocus = o->isWidgetType() ? (QWidget*) o : 0;
-        setActive(_lastFocus != 0);
+        _lastFocus = o->isWidgetType() ? (QWidget*) o : nullptr;
+        setActive(_lastFocus != nullptr);
     }
     return QWidget::eventFilter(o,e);
 }
@@ -742,7 +742,7 @@
     bool canShow;
     foreach(TraceItemView *v, _tabs) {
 
-        TabWidget *tw = 0;
+        TabWidget *tw = nullptr;
         switch(v->position()) {
         case TraceItemView::Top:    tw = _topTW; break;
         case TraceItemView::Bottom: tw = _bottomTW; break;
@@ -861,10 +861,10 @@
         bottomTabs = bottomTabsDefault;
     }
 
-    TraceItemView *activeTop = 0, *activeBottom = 0;
-    TraceItemView *activeLeft = 0, *activeRight = 0;
+    TraceItemView *activeTop = nullptr, *activeBottom = nullptr;
+    TraceItemView *activeLeft = nullptr, *activeRight = nullptr;
 
-    moveTab(0, TraceItemView::Top, true);
+    moveTab(nullptr, TraceItemView::Top, true);
     foreach(TraceItemView *v, _tabs) {
         QString n = v->widget()->objectName();
         if (topTabs.contains(n)) {
diff --git a/libviews/traceitemview.h b/libviews/traceitemview.h
--- a/libviews/traceitemview.h
+++ b/libviews/traceitemview.h
@@ -92,7 +92,7 @@
     // a TraceItemView can have a position in a parent container
     enum Position { Hidden, Top, Right, Left, Bottom };
 
-    explicit TraceItemView(TraceItemView* parentView, TopLevelBase* top = 0);
+    explicit TraceItemView(TraceItemView* parentView, TopLevelBase* top = nullptr);
     virtual ~TraceItemView();
 
     virtual QString whatsThis() const;
diff --git a/libviews/traceitemview.cpp b/libviews/traceitemview.cpp
--- a/libviews/traceitemview.cpp
+++ b/libviews/traceitemview.cpp
@@ -51,12 +51,12 @@
     _parentView = parentView;
     _topLevel = top ? top : parentView->topLevel();
 
-    _data = _newData = 0;
+    _data = _newData = nullptr;
     // _partList and _newPartList is empty
-    _activeItem = _newActiveItem = 0;
-    _selectedItem = _newSelectedItem = 0;
-    _eventType = _newEventType = 0;
-    _eventType2 = _newEventType2 = 0;
+    _activeItem = _newActiveItem = nullptr;
+    _selectedItem = _newSelectedItem = nullptr;
+    _eventType = _newEventType = nullptr;
+    _eventType2 = _newEventType2 = nullptr;
     _groupType = _newGroupType = ProfileContext::InvalidType;
 
     _status = nothingChanged;
@@ -113,16 +113,16 @@
     _newActiveItem = canShow(i);
     if (_activeItem != _newActiveItem) {
         // new item activated, start with empty selection
-        _newSelectedItem = 0;
+        _newSelectedItem = nullptr;
         updateView();
     }
 
-    return (_newActiveItem != 0);
+    return (_newActiveItem != nullptr);
 }
 
 TraceFunction* TraceItemView::activeFunction()
 {
-    if (!_activeItem) return 0;
+    if (!_activeItem) return nullptr;
 
     ProfileContext::Type t = _activeItem->type();
     switch(t) {
@@ -132,7 +132,7 @@
     default:
         break;
     }
-    return 0;
+    return nullptr;
 }
 
 bool TraceItemView::set(int changeType, TraceData* d,
@@ -150,11 +150,11 @@
     _newActiveItem = canShow(a);
     if (_activeItem != _newActiveItem) {
         // new item activated, start with empty selection
-        _newSelectedItem = 0;
+        _newSelectedItem = nullptr;
     }
     updateView();
 
-    return (_newActiveItem != 0);
+    return (_newActiveItem != nullptr);
 }
 
 
@@ -172,10 +172,10 @@
     _newData = d;
 
     // invalidate all pointers to old data
-    _activeItem = _newActiveItem = 0;
-    _selectedItem = _newSelectedItem = 0;
-    _eventType = _newEventType = 0;
-    _eventType2 = _newEventType2 = 0;
+    _activeItem = _newActiveItem = nullptr;
+    _selectedItem = _newSelectedItem = nullptr;
+    _eventType = _newEventType = nullptr;
+    _eventType2 = _newEventType2 = nullptr;
     _groupType = _newGroupType = ProfileContext::InvalidType;
     _partList.clear();
     _newPartList.clear();
@@ -236,7 +236,7 @@
     if (_newActiveItem != _activeItem) {
 
         // when setting a new active item, there is no selection
-        _selectedItem = 0;
+        _selectedItem = nullptr;
 
         _status |= activeItemChanged;
         _activeItem = _newActiveItem;
diff --git a/libviews/treemap.h b/libviews/treemap.h
--- a/libviews/treemap.h
+++ b/libviews/treemap.h
@@ -104,20 +104,20 @@
                               bool selected = false, bool current = false);
 
     // getters
-    QString  text(int) const;
-    QPixmap  pixmap(int) const;
-    Position position(int) const;
-    int      maxLines(int) const;
-    int      fieldCount() const { return _field.size(); }
+    QString  text(int) const override;
+    QPixmap  pixmap(int) const override;
+    Position position(int) const override;
+    int      maxLines(int) const override;
+    int      fieldCount() const override { return _field.size(); }
 
-    QColor   backColor() const { return _backColor; }
-    bool selected() const { return _selected; }
-    bool current() const { return _current; }
-    bool shaded() const { return _shaded; }
-    bool rotated() const { return _rotated; }
-    bool drawFrame() const { return _drawFrame; }
+    QColor   backColor() const override { return _backColor; }
+    bool selected() const override { return _selected; }
+    bool current() const override { return _current; }
+    bool shaded() const override { return _shaded; }
+    bool rotated() const override { return _rotated; }
+    bool drawFrame() const override { return _drawFrame; }
 
-    const QFont& font() const;
+    const QFont& font() const override;
 
     // attribute setters
     void setField(int f, const QString& t, const QPixmap& pm = QPixmap(),
@@ -177,18 +177,18 @@
     void setDrawParams(DrawParams*);
 
     // draw on a given QPainter, use this class as info provider per default
-    void drawBack(QPainter*, DrawParams* dp = 0);
+    void drawBack(QPainter*, DrawParams* dp = nullptr);
     /* Draw field at position() from pixmap()/text() with maxLines().
      * Returns true if something was drawn
      */
-    bool drawField(QPainter*, int f, DrawParams* dp = 0);
+    bool drawField(QPainter*, int f, DrawParams* dp = nullptr);
 
     // resets rectangle for free space
     void setRect(const QRect&);
 
     // Returns the rectangle area still free of text/pixmaps after
     // a number of drawText() calls.
-    QRect remainingRect(DrawParams* dp = 0);
+    QRect remainingRect(DrawParams* dp = nullptr);
 
 private:
     int _usedTopLeft, _usedTopCenter, _usedTopRight;
@@ -241,11 +241,11 @@
                      HAlternate, VAlternate,
                      Horizontal, Vertical };
 
-    explicit TreeMapItem(TreeMapItem* parent = 0, double value = 1.0 );
+    explicit TreeMapItem(TreeMapItem* parent = nullptr, double value = 1.0 );
     TreeMapItem(TreeMapItem* parent, double value,
                 const QString& text1, const QString& text2 = QString(),
                 const QString& text3 = QString(), const QString& text4 = QString());
-    virtual ~TreeMapItem();
+    ~TreeMapItem() override;
 
     bool isChildOf(TreeMapItem*);
 
@@ -326,8 +326,8 @@
     virtual double sum() const;
     virtual double value() const;
     // replace "Default" position with setting from TreeMapWidget
-    virtual Position position(int) const;
-    virtual const QFont& font() const;
+    Position position(int) const override;
+    const QFont& font() const override;
     virtual bool isMarked(int) const;
 
     virtual int borderWidth() const;
@@ -405,8 +405,8 @@
     enum SelectionMode { Single, Multi, Extended, NoSelection };
 
     /* The widget gets owner of the base item */
-    explicit TreeMapWidget(TreeMapItem* base, QWidget* parent=0);
-    ~TreeMapWidget();
+    explicit TreeMapWidget(TreeMapItem* base, QWidget* parent=nullptr);
+    ~TreeMapWidget() override;
 
     /**
      * Returns the TreeMapItem filling out the widget space
@@ -460,7 +460,7 @@
      * parent. When parent == 0, clears whole selection
      * Returns true if selection changed.
      */
-    bool clearSelection(TreeMapItem* parent = 0);
+    bool clearSelection(TreeMapItem* parent = nullptr);
 
     /**
      * Selects or unselects items in a range.
@@ -664,15 +664,15 @@
     void contextMenuRequested(TreeMapItem*, const QPoint &);
 
 protected:
-    void mousePressEvent( QMouseEvent * );
-    void contextMenuEvent( QContextMenuEvent * );
-    void mouseReleaseEvent( QMouseEvent * );
-    void mouseMoveEvent( QMouseEvent * );
-    void mouseDoubleClickEvent( QMouseEvent * );
-    void keyPressEvent( QKeyEvent* );
-    void paintEvent( QPaintEvent * );
+    void mousePressEvent( QMouseEvent * ) override;
+    void contextMenuEvent( QContextMenuEvent * ) override;
+    void mouseReleaseEvent( QMouseEvent * ) override;
+    void mouseMoveEvent( QMouseEvent * ) override;
+    void mouseDoubleClickEvent( QMouseEvent * ) override;
+    void keyPressEvent( QKeyEvent* ) override;
+    void paintEvent( QPaintEvent * ) override;
     void fontChange( const QFont& );
-    bool event(QEvent *event);
+    bool event(QEvent *event) override;
 
 private:
     TreeMapItemList diff(TreeMapItemList&, TreeMapItemList&);
diff --git a/libviews/treemap.cpp b/libviews/treemap.cpp
--- a/libviews/treemap.cpp
+++ b/libviews/treemap.cpp
@@ -110,7 +110,7 @@
 
 const QFont& StoredDrawParams::font() const
 {
-    static QFont* f = 0;
+    static QFont* f = nullptr;
     if (!f) f = new QFont(QApplication::font());
 
     return *f;
@@ -184,8 +184,8 @@
 
 RectDrawing::RectDrawing(const QRect& r)
 {
-    _fm = 0;
-    _dp = 0;
+    _fm = nullptr;
+    _dp = nullptr;
     setRect(r);
 }
 
@@ -503,7 +503,7 @@
     bool isBottom = false;
     bool isCenter = false;
     bool isRight = false;
-    int* used = 0;
+    int* used = nullptr;
     switch(pos) {
     case DrawParams::TopLeft:
         used = &_usedTopLeft;
@@ -809,7 +809,7 @@
 
 TreeMapItem* TreeMapItemList::commonParent()
 {
-    if (isEmpty()) return 0;
+    if (isEmpty()) return nullptr;
 
     TreeMapItem* parent = first();
     for(int i = 1; parent && i<size(); i++)
@@ -857,8 +857,8 @@
     _parent = parent;
 
     _sum = 0;
-    _children = 0;
-    _widget = 0;
+    _children = nullptr;
+    _widget = nullptr;
     _index = -1;
     _depth = -1; // not set
     _unused_self = 0;
@@ -889,8 +889,8 @@
     setText(0, text1);
 
     _sum = 0;
-    _children = 0;
-    _widget = 0;
+    _children = nullptr;
+    _widget = nullptr;
     _index = -1;
     _depth = -1; // not set
     _unused_self = 0;
@@ -905,7 +905,7 @@
     if (_children) {
         qDeleteAll(*_children);
         delete _children;
-        _children = 0;
+        _children = nullptr;
     }
 
     // finally, notify widget about deletion
@@ -952,7 +952,7 @@
 
         qDeleteAll(*_children);
         delete _children;
-        _children = 0;
+        _children = nullptr;
     }
 }
 
@@ -1009,7 +1009,7 @@
     i->setParent(this);
 
     _children->append(i); // preserve insertion order
-    if (sorting(0) != -1)
+    if (sorting(nullptr) != -1)
         std::sort(_children->begin(), _children->end(), treeMapItemLessThan);
 }
 
@@ -1206,10 +1206,10 @@
     // _forceText will be false on resizing (per default)
 
     // start state: _selection is an empty list
-    _current = 0;
-    _oldCurrent = 0;
-    _pressed = 0;
-    _lastOver = 0;
+    _current = nullptr;
+    _oldCurrent = nullptr;
+    _pressed = nullptr;
+    _lastOver = nullptr;
     _needsRefresh = _base;
 
     setAttribute(Qt::WA_NoSystemBackground, true);
@@ -1524,10 +1524,10 @@
     _selection.removeAll(i);
     _tmpSelection.removeAll(i);
 
-    if (_current == i) _current = 0;
-    if (_oldCurrent == i) _oldCurrent = 0;
-    if (_pressed == i) _pressed = 0;
-    if (_lastOver == i) _lastOver = 0;
+    if (_current == i) _current = nullptr;
+    if (_oldCurrent == i) _oldCurrent = nullptr;
+    if (_pressed == i) _pressed = nullptr;
+    if (_lastOver == i) _lastOver = nullptr;
 
     // do not redraw a deleted item
     if (_needsRefresh == i) {
@@ -1561,14 +1561,14 @@
 TreeMapItem* TreeMapWidget::item(int x, int y) const
 {
 
-    if (!rect().contains(x, y)) return 0;
+    if (!rect().contains(x, y)) return nullptr;
     if (DEBUG_DRAWING) qDebug() << "item(" << x << "," << y << "):";
 
     TreeMapItem* p = _base;
     TreeMapItem* i;
     while (1) {
         TreeMapItemList* list = p->children();
-        i = 0;
+        i = nullptr;
         if (list) {
             int idx;
             for (idx=0; idx<list->size(); idx++) {
@@ -1588,11 +1588,11 @@
                     break;
                 }
             }
-            if (idx == list->size()) i = 0; // not contained in child
+            if (idx == list->size()) i = nullptr; // not contained in child
         }
 
         if (!i) {
-            static TreeMapItem* last = 0;
+            static TreeMapItem* last = nullptr;
             if (p != last) {
                 last = p;
 
@@ -1607,7 +1607,7 @@
         }
         p = i;
     }
-    return 0;
+    return nullptr;
 }
 
 TreeMapItem* TreeMapWidget::possibleSelection(TreeMapItem* i) const
@@ -1696,8 +1696,8 @@
  */
 TreeMapItem* TreeMapWidget::setTmpSelected(TreeMapItem* item, bool selected)
 {
-    if (!item) return 0;
-    if (_selectionMode == NoSelection) return 0;
+    if (!item) return nullptr;
+    if (_selectionMode == NoSelection) return nullptr;
 
     TreeMapItemList old = _tmpSelection;
 
@@ -1736,7 +1736,7 @@
         changed->redraw();
         emit selectionChanged();
     }
-    return (changed != 0);
+    return (changed != nullptr);
 }
 
 bool TreeMapWidget::isSelected(TreeMapItem* i) const
@@ -1802,9 +1802,9 @@
                                                  TreeMapItem* i2,
                                                  bool selected)
 {
-    if ((i1 == 0) && (i2 == 0)) return 0;
-    if ((i1 == 0) || i1->isChildOf(i2)) return setTmpSelected(i2, selected);
-    if ((i2 == 0) || i2->isChildOf(i1)) return setTmpSelected(i1, selected);
+    if ((i1 == nullptr) && (i2 == nullptr)) return nullptr;
+    if ((i1 == nullptr) || i1->isChildOf(i2)) return setTmpSelected(i2, selected);
+    if ((i2 == nullptr) || i2->isChildOf(i1)) return setTmpSelected(i1, selected);
 
     TreeMapItem* changed = setTmpSelected(i1, selected);
     TreeMapItem* changed2 = setTmpSelected(i2, selected);
@@ -1870,7 +1870,7 @@
     _inControlDrag = e->modifiers() & Qt::ControlModifier;
     _lastOver = _pressed;
 
-    TreeMapItem* changed = 0;
+    TreeMapItem* changed = nullptr;
     TreeMapItem* item = possibleSelection(_pressed);
 
     switch(_selectionMode) {
@@ -1918,8 +1918,8 @@
                 emit selectionChanged(_lastOver);
             emit selectionChanged();
         }
-        _pressed = 0;
-        _lastOver = 0;
+        _pressed = nullptr;
+        _lastOver = nullptr;
         emit rightButtonPressed(i, e->pos());
     }
 }
@@ -1933,12 +1933,12 @@
     if (_lastOver == over) return;
 
     setCurrent(over);
-    if (over == 0) {
-        _lastOver = 0;
+    if (over == nullptr) {
+        _lastOver = nullptr;
         return;
     }
 
-    TreeMapItem* changed = 0;
+    TreeMapItem* changed = nullptr;
     TreeMapItem* item = possibleSelection(over);
 
     switch(_selectionMode) {
@@ -1992,8 +1992,8 @@
             emit clicked(_lastOver);
     }
 
-    _pressed = 0;
-    _lastOver = 0;
+    _pressed = nullptr;
+    _lastOver = nullptr;
 }
 
 
@@ -2057,8 +2057,8 @@
             if (changed)
                 redraw(changed);
         }
-        _pressed = 0;
-        _lastOver = 0;
+        _pressed = nullptr;
+        _lastOver = nullptr;
     }
 
     if ((e->key() == Qt::Key_Space) ||
@@ -2229,7 +2229,7 @@
         _fontHeight = fontMetrics().height();
 
         drawItems(&p, _needsRefresh);
-        _needsRefresh = 0;
+        _needsRefresh = nullptr;
     }
 
     QPainter p(this);
@@ -2536,7 +2536,7 @@
             QRect firstRect = QRect(r.x(), r.y(), nextPos, r.height());
 
             if (nextPos < _visibleWidth) {
-                if (item->sorting(0) == -1) {
+                if (item->sorting(nullptr) == -1) {
                     // fill current rect with hash pattern
                     drawFill(item, p, firstRect);
                 }
@@ -2555,7 +2555,7 @@
             len = lenLeft;
 
             if (!drawDetails) {
-                if (item->sorting(0) == -1)
+                if (item->sorting(nullptr) == -1)
                     drawDetails = true;
                 else {
                     drawFill(item, p, r, list, idx, len, goBack);
@@ -2587,7 +2587,7 @@
             QRect firstRect = QRect(r.x(), r.y(), r.width(), nextPos);
 
             if (nextPos < _visibleWidth) {
-                if (item->sorting(0) == -1) {
+                if (item->sorting(nullptr) == -1) {
                     drawFill(item, p, firstRect);
                 }
                 else {
@@ -2604,7 +2604,7 @@
             len = lenLeft;
 
             if (!drawDetails) {
-                if (item->sorting(0) == -1)
+                if (item->sorting(nullptr) == -1)
                     drawDetails = true;
                 else {
                     drawFill(item, p, r, list, idx, len, goBack);
@@ -2716,7 +2716,7 @@
         }
 
         // if no sorting, do not stop drawing
-        if (item->sorting(0) == -1) drawOn = true;
+        if (item->sorting(nullptr) == -1) drawOn = true;
 
         // second half
         if (drawOn)
@@ -2771,7 +2771,7 @@
         int nextPos = (user_sum <= 0.0) ? 0: (int)(lastPos * val / user_sum +.5);
         if (nextPos>lastPos) nextPos = lastPos;
 
-        if ((item->sorting(0) != -1) && (nextPos < _visibleWidth)) {
+        if ((item->sorting(nullptr) != -1) && (nextPos < _visibleWidth)) {
             drawFill(item, p, fullRect, list, idx, len, goBack);
             if (DEBUG_DRAWING)
                 qDebug() << " -drawItemArray(" << item->path(0).join(QStringLiteral("/"))
diff --git a/qcachegrind/colorsettings.h b/qcachegrind/colorsettings.h
--- a/qcachegrind/colorsettings.h
+++ b/qcachegrind/colorsettings.h
@@ -36,11 +36,11 @@
 
 public:
     ColorSettings(TraceData* data, QWidget* parent);
-    virtual ~ColorSettings();
+    ~ColorSettings() override;
 
-    bool check(QString&, QString&);
-    void accept();
-    void activate(QString s);
+    bool check(QString&, QString&) override;
+    void accept() override;
+    void activate(QString s) override;
 
 public slots:
     void resetClicked();
diff --git a/qcachegrind/colorsettings.cpp b/qcachegrind/colorsettings.cpp
--- a/qcachegrind/colorsettings.cpp
+++ b/qcachegrind/colorsettings.cpp
@@ -100,7 +100,7 @@
     connect(ui.colorButton, &QtColorButton::colorChanged,
             this, &ColorSettings::colorChanged);
 
-    _current = 0;
+    _current = nullptr;
     update();
 }
 
diff --git a/qcachegrind/configdialog.h b/qcachegrind/configdialog.h
--- a/qcachegrind/configdialog.h
+++ b/qcachegrind/configdialog.h
@@ -49,7 +49,7 @@
     QString currentPage();
 
 public slots:
-    void accept();
+    void accept() override;
     void listItemChanged(QString);
     void clearError();
 
diff --git a/qcachegrind/configpage.h b/qcachegrind/configpage.h
--- a/qcachegrind/configpage.h
+++ b/qcachegrind/configpage.h
@@ -32,7 +32,7 @@
     Q_OBJECT
 public:
     ConfigPage(QWidget* parent, QString title, QString longTitle = QString());
-    virtual ~ConfigPage() {}
+    ~ConfigPage() override {}
 
     QString title() { return _title; }
     QString longTitle() { return _longTitle; }
diff --git a/qcachegrind/generalsettings.h b/qcachegrind/generalsettings.h
--- a/qcachegrind/generalsettings.h
+++ b/qcachegrind/generalsettings.h
@@ -31,10 +31,10 @@
     Q_OBJECT
 public:
     explicit GeneralSettings(QWidget* parent);
-    virtual ~GeneralSettings() {}
+    ~GeneralSettings() override {}
 
-    bool check(QString&, QString&);
-    void accept();
+    bool check(QString&, QString&) override;
+    void accept() override;
 
 private:
     Ui::GeneralSettings ui;
diff --git a/qcachegrind/qcgconfig.h b/qcachegrind/qcgconfig.h
--- a/qcachegrind/qcgconfig.h
+++ b/qcachegrind/qcgconfig.h
@@ -33,11 +33,11 @@
     friend class QCGConfigStorage;
 
 public:
-    ~QCGConfigGroup();
+    ~QCGConfigGroup() override;
 
     void setValue(const QString& key, const QVariant& value,
-                  const QVariant& defaultValue = QVariant());
-    QVariant value(const QString& key, const QVariant& defaultValue) const;
+                  const QVariant& defaultValue = QVariant()) override;
+    QVariant value(const QString& key, const QVariant& defaultValue) const override;
 
 private:
     QCGConfigGroup(QSettings*, QString prefix, bool);
@@ -52,11 +52,11 @@
 {
 public:
     QCGConfigStorage();
-    ~QCGConfigStorage();
+    ~QCGConfigStorage() override;
 
 private:
     ConfigGroup* getGroup(const QString& group,
-                          const QString& optSuffix);
+                          const QString& optSuffix) override;
 
     QSettings* _settings;
 };
diff --git a/qcachegrind/qcgconfig.cpp b/qcachegrind/qcgconfig.cpp
--- a/qcachegrind/qcgconfig.cpp
+++ b/qcachegrind/qcgconfig.cpp
@@ -45,7 +45,7 @@
 void QCGConfigGroup::setValue(const QString& key, const QVariant& value,
                               const QVariant& defaultValue)
 {
-    if ((_settings == 0) || _readOnly) return;
+    if ((_settings == nullptr) || _readOnly) return;
 
     QString fullKey = QStringLiteral("%1/%2").arg(_prefix).arg(key);
     if (value == defaultValue)
@@ -57,7 +57,7 @@
 QVariant QCGConfigGroup::value(const QString& key,
                                const QVariant& defaultValue) const
 {
-    if (_settings == 0) return defaultValue;
+    if (_settings == nullptr) return defaultValue;
 
     QString fullKey = QStringLiteral("%1/%2").arg(_prefix).arg(key);
     return _settings->value(fullKey, defaultValue);
@@ -94,5 +94,5 @@
         return new QCGConfigGroup(_settings, group, true);
 
     // requested group does not exist, return only default values
-    return new QCGConfigGroup(0, QString(), true);
+    return new QCGConfigGroup(nullptr, QString(), true);
 }
diff --git a/qcachegrind/qcgtoplevel.h b/qcachegrind/qcgtoplevel.h
--- a/qcachegrind/qcgtoplevel.h
+++ b/qcachegrind/qcgtoplevel.h
@@ -55,7 +55,7 @@
 
 public:
     QCGTopLevel();
-    ~QCGTopLevel();
+    ~QCGTopLevel() override;
 
     TraceData* data() { return _data; }
     void setData(TraceData*);
@@ -65,24 +65,24 @@
     void createMenu();
     void createToolbar();
 
-    void closeEvent(QCloseEvent*);
+    void closeEvent(QCloseEvent*) override;
 
     ProfileContext::Type groupType() { return _groupType; }
     EventType* eventType() { return _eventType; }
     EventType* eventType2() { return _eventType2; }
     TracePartList activeParts() { return _activeParts; }
-    TracePartList hiddenParts() { return _hiddenParts; }
+    TracePartList hiddenParts() override { return _hiddenParts; }
 
     /* convenience functions for often used context menu items */
-    void addEventTypeMenu(QMenu*,bool);
-    void addGoMenu(QMenu*);
+    void addEventTypeMenu(QMenu*,bool) override;
+    void addGoMenu(QMenu*) override;
 
     // Logger overwrites: notifications for file loading
-    virtual void loadStart(const QString& filename);
-    virtual void loadProgress(int progress); // 0 - 100
-    virtual void loadWarning(int line, const QString& msg);
-    virtual void loadError(int line, const QString& msg);
-    virtual void loadFinished(const QString& msg); // msg could be error
+    void loadStart(const QString& filename) override;
+    void loadProgress(int progress) override; // 0 - 100
+    void loadWarning(int line, const QString& msg) override;
+    void loadError(int line, const QString& msg) override;
+    void loadFinished(const QString& msg) override; // msg could be error
 
 public slots:
     void load();
@@ -150,25 +150,25 @@
     bool setGroup(QString);
     bool setFunction(TraceFunction*);
     bool setFunction(QString);
-    void activePartsChangedSlot(const TracePartList& list);
+    void activePartsChangedSlot(const TracePartList& list) override;
     void partsHideSelectedSlot();
     void partsUnhideAllSlot();
 
     /* These go back to mainloop first by using a timer.
    * So they can be called from event handlers that
    * are not allowed to delete list entries.
    */
-    void setEventTypeDelayed(EventType*);
-    void setEventType2Delayed(EventType*);
-    void setGroupTypeDelayed(ProfileContext::Type);
-    void setGroupDelayed(TraceCostItem*);
-    void setTraceItemDelayed(CostItem*);
+    void setEventTypeDelayed(EventType*) override;
+    void setEventType2Delayed(EventType*) override;
+    void setGroupTypeDelayed(ProfileContext::Type) override;
+    void setGroupDelayed(TraceCostItem*) override;
+    void setTraceItemDelayed(CostItem*) override;
     void partsHideSelectedSlotDelayed();
     void partsUnhideAllSlotDelayed();
     void goBack();
     void goForward();
     void goUp();
-    void setDirectionDelayed(TraceItemView::Direction);
+    void setDirectionDelayed(TraceItemView::Direction) override;
 
     /* SingleShot Slots (without parameters) for the delayed versions */
     void setEventTypeDelayed();
@@ -180,13 +180,13 @@
     void setDirectionDelayed();
 
     // configuration has changed
-    void configChanged();
+    void configChanged() override;
 
     //void refresh();
 
     // progress in status bar, empty message disables progress display
     void showStatus(const QString& msg, int progress);
-    void showMessage(const QString&, int msec);
+    void showMessage(const QString&, int msec) override;
 
 private:
     void resetState();
diff --git a/qcachegrind/qcgtoplevel.cpp b/qcachegrind/qcgtoplevel.cpp
--- a/qcachegrind/qcgtoplevel.cpp
+++ b/qcachegrind/qcgtoplevel.cpp
@@ -66,7 +66,7 @@
                        QDBusConnection::ExportScriptableSlots);
 #endif
 
-    _progressBar = 0;
+    _progressBar = nullptr;
     _statusbar = statusBar();
     _statusLabel = new QLabel(_statusbar);
     _statusbar->addWidget(_statusLabel, 1);
@@ -118,21 +118,21 @@
     _activeParts.clear();
     _hiddenParts.clear();
 
-    _data = 0;
-    _function = 0;
-    _eventType = 0;
-    _eventType2 = 0;
+    _data = nullptr;
+    _function = nullptr;
+    _eventType = nullptr;
+    _eventType2 = nullptr;
     _groupType = ProfileContext::InvalidType;
-    _group = 0;
+    _group = nullptr;
 
     // for delayed slots
-    _traceItemDelayed = 0;
-    _eventTypeDelayed = 0;
-    _eventType2Delayed = 0;
+    _traceItemDelayed = nullptr;
+    _eventTypeDelayed = nullptr;
+    _eventType2Delayed = nullptr;
     _groupTypeDelayed = ProfileContext::InvalidType;
-    _groupDelayed = 0;
+    _groupDelayed = nullptr;
     _directionDelayed = TraceItemView::None;
-    _lastSender = 0;
+    _lastSender = nullptr;
 }
 
 
@@ -916,7 +916,7 @@
 {
     EventType* ct;
 
-    ct = (_data) ? _data->eventTypes()->type(s) : 0;
+    ct = (_data) ? _data->eventTypes()->type(s) : nullptr;
 
     // if costtype with given name not found, use first available
     if (!ct && _data) ct = _data->eventTypes()->type(0);
@@ -929,24 +929,24 @@
     EventType* ct;
 
     // Special type tr("(Hidden)") gives 0
-    ct = (_data) ? _data->eventTypes()->type(s) : 0;
+    ct = (_data) ? _data->eventTypes()->type(s) : nullptr;
 
     return setEventType2(ct);
 }
 
 void QCGTopLevel::eventTypeSelected(const QString& s)
 {
     EventType* ct;
 
-    ct = (_data) ? _data->eventTypes()->typeForLong(s) : 0;
+    ct = (_data) ? _data->eventTypes()->typeForLong(s) : nullptr;
     setEventType(ct);
 }
 
 void QCGTopLevel::eventType2Selected(const QString& s)
 {
     EventType* ct;
 
-    ct = (_data) ? _data->eventTypes()->typeForLong(s) : 0;
+    ct = (_data) ? _data->eventTypes()->typeForLong(s) : nullptr;
     setEventType2(ct);
 }
 
@@ -1185,9 +1185,9 @@
 
     case TraceItemView::Up:
     {
-        StackBrowser* b = _stackSelection ? _stackSelection->browser() : 0;
-        HistoryItem* hi = b ? b->current() : 0;
-        TraceFunction* f = hi ? hi->function() : 0;
+        StackBrowser* b = _stackSelection ? _stackSelection->browser() : nullptr;
+        HistoryItem* hi = b ? b->current() : nullptr;
+        TraceFunction* f = hi ? hi->function() : nullptr;
 
         if (!f) break;
         f = hi->stack()->caller(f, false);
@@ -1245,8 +1245,8 @@
     default: break;
     }
 
-    _traceItemDelayed = 0;
-    _lastSender = 0;
+    _traceItemDelayed = nullptr;
+    _lastSender = nullptr;
 }
 
 /**
@@ -1259,15 +1259,15 @@
 {
     if (data == _data) return;
 
-    _lastSender = 0;
+    _lastSender = nullptr;
 
     saveTraceSettings();
 
     if (_data) {
-        _partSelection->setData(0);
-        _stackSelection->setData(0);
-        _functionSelection->setData(0);
-        _multiView->setData(0);
+        _partSelection->setData(nullptr);
+        _stackSelection->setData(nullptr);
+        _functionSelection->setData(nullptr);
+        _multiView->setData(nullptr);
         _multiView->updateView(true);
 
         // we are the owner...
@@ -1344,7 +1344,7 @@
         connect(m, SIGNAL(triggered(QAction*)),
                 this, SLOT(setEventType2(QAction*)), Qt::UniqueConnection);
 
-        if (_eventType2 != 0) {
+        if (_eventType2 != nullptr) {
             action = m->addAction(tr("Hide"));
             action->setData(199);
             m->addSeparator();
@@ -1399,10 +1399,10 @@
 bool QCGTopLevel::setEventType(QAction* action)
 {
     if (!_data) return false;
-    int id = action->data().toInt(0);
+    int id = action->data().toInt(nullptr);
 
     EventTypeSet* m = _data->eventTypes();
-    EventType* ct=0;
+    EventType* ct=nullptr;
     if (id >=100 && id<199) ct = m->realType(id-100);
     if (id >=200 && id<299) ct = m->derivedType(id-200);
 
@@ -1412,10 +1412,10 @@
 bool QCGTopLevel::setEventType2(QAction* action)
 {
     if (!_data) return false;
-    int id = action->data().toInt(0);
+    int id = action->data().toInt(nullptr);
 
     EventTypeSet* m = _data->eventTypes();
-    EventType* ct=0;
+    EventType* ct=nullptr;
     if (id >=100 && id<199) ct = m->realType(id-100);
     if (id >=200 && id<299) ct = m->derivedType(id-200);
 
@@ -1832,8 +1832,8 @@
     QMenu *popup = _forwardAction->menu();
 
     popup->clear();
-    StackBrowser* b = _stackSelection ? _stackSelection->browser() : 0;
-    HistoryItem* hi = b ? b->current() : 0;
+    StackBrowser* b = _stackSelection ? _stackSelection->browser() : nullptr;
+    HistoryItem* hi = b ? b->current() : nullptr;
     TraceFunction* f;
     QAction* action;
 
@@ -1869,8 +1869,8 @@
     QMenu *popup = _backAction->menu();
 
     popup->clear();
-    StackBrowser* b = _stackSelection ? _stackSelection->browser() : 0;
-    HistoryItem* hi = b ? b->current() : 0;
+    StackBrowser* b = _stackSelection ? _stackSelection->browser() : nullptr;
+    HistoryItem* hi = b ? b->current() : nullptr;
     TraceFunction* f;
     QAction* action;
 
@@ -1906,9 +1906,9 @@
     QMenu *popup = _upAction->menu();
 
     popup->clear();
-    StackBrowser* b = _stackSelection ? _stackSelection->browser() : 0;
-    HistoryItem* hi = b ? b->current() : 0;
-    TraceFunction* f = hi ? hi->function() : 0;
+    StackBrowser* b = _stackSelection ? _stackSelection->browser() : nullptr;
+    HistoryItem* hi = b ? b->current() : nullptr;
+    TraceFunction* f = hi ? hi->function() : nullptr;
     QAction* action;
 
     if (!f) {
@@ -1935,12 +1935,12 @@
 
 void QCGTopLevel::forwardTriggered(QAction* action)
 {
-    int count = action->data().toInt(0);
+    int count = action->data().toInt(nullptr);
     //qDebug("forwardTriggered: %d", count);
     if( count <= 0)
         return;
 
-    StackBrowser* b = _stackSelection ? _stackSelection->browser() : 0;
+    StackBrowser* b = _stackSelection ? _stackSelection->browser() : nullptr;
     if (!b) return;
 
     while (count>1) {
@@ -1952,12 +1952,12 @@
 
 void QCGTopLevel::backTriggered(QAction* action)
 {
-    int count = action->data().toInt(0);
+    int count = action->data().toInt(nullptr);
     //qDebug("backTriggered: %d", count);
     if( count <= 0)
         return;
 
-    StackBrowser* b = _stackSelection ? _stackSelection->browser() : 0;
+    StackBrowser* b = _stackSelection ? _stackSelection->browser() : nullptr;
     if (!b) return;
 
     while (count>1) {
@@ -1969,13 +1969,13 @@
 
 void QCGTopLevel::upTriggered(QAction* action)
 {
-    int count = action->data().toInt(0);
+    int count = action->data().toInt(nullptr);
     //qDebug("upTriggered: %d", count);
     if( count <= 0)
         return;
 
-    StackBrowser* b = _stackSelection ? _stackSelection->browser() : 0;
-    HistoryItem* hi = b ? b->current() : 0;
+    StackBrowser* b = _stackSelection ? _stackSelection->browser() : nullptr;
+    HistoryItem* hi = b ? b->current() : nullptr;
     if (!hi) return;
 
     TraceFunction* f = hi->function();
@@ -2007,7 +2007,7 @@
         if (_progressBar) {
             _statusbar->removeWidget(_progressBar);
             delete _progressBar;
-            _progressBar = 0;
+            _progressBar = nullptr;
         }
         _statusbar->clearMessage();
         _progressMsg = msg;
diff --git a/qcachegrind/qtcolorbutton.h b/qcachegrind/qtcolorbutton.h
--- a/qcachegrind/qtcolorbutton.h
+++ b/qcachegrind/qtcolorbutton.h
@@ -44,8 +44,8 @@
     Q_OBJECT
     Q_PROPERTY(bool backgroundCheckered READ isBackgroundCheckered WRITE setBackgroundCheckered)
 public:
-    explicit QtColorButton(QWidget *parent = 0);
-    ~QtColorButton();
+    explicit QtColorButton(QWidget *parent = nullptr);
+    ~QtColorButton() override;
 
     bool isBackgroundCheckered() const;
     void setBackgroundCheckered(bool checkered);
@@ -59,13 +59,13 @@
 signals:
     void colorChanged(const QColor &color);
 protected:
-    void paintEvent(QPaintEvent *event);
-    void mousePressEvent(QMouseEvent *event);
-    void mouseMoveEvent(QMouseEvent *event);
+    void paintEvent(QPaintEvent *event) override;
+    void mousePressEvent(QMouseEvent *event) override;
+    void mouseMoveEvent(QMouseEvent *event) override;
 #ifndef QT_NO_DRAGANDDROP
-    void dragEnterEvent(QDragEnterEvent *event);
-    void dragLeaveEvent(QDragLeaveEvent *event);
-    void dropEvent(QDropEvent *event);
+    void dragEnterEvent(QDragEnterEvent *event) override;
+    void dragLeaveEvent(QDragLeaveEvent *event) override;
+    void dropEvent(QDropEvent *event) override;
 #endif
 private:
     class QtColorButtonPrivate* d_ptr;
diff --git a/qcachegrind/sourcesettings.h b/qcachegrind/sourcesettings.h
--- a/qcachegrind/sourcesettings.h
+++ b/qcachegrind/sourcesettings.h
@@ -35,11 +35,11 @@
 
 public:
     SourceSettings(TraceData* data, QWidget* parent);
-    virtual ~SourceSettings() {}
+    ~SourceSettings() override {}
 
-    bool check(QString&, QString&);
-    void accept();
-    void activate(QString s);
+    bool check(QString&, QString&) override;
+    void accept() override;
+    void activate(QString s) override;
 
 public slots:
     void addClicked();
diff --git a/qcachegrind/sourcesettings.cpp b/qcachegrind/sourcesettings.cpp
--- a/qcachegrind/sourcesettings.cpp
+++ b/qcachegrind/sourcesettings.cpp
@@ -96,7 +96,7 @@
     connect(ui.dirEdit, SIGNAL(textChanged(QString)),
             this, SLOT(dirEditChanged(QString)));
 
-    _current = 0;
+    _current = nullptr;
     update();
 }
 
@@ -144,7 +144,7 @@
     delete _current;
     // deletion can trigger a call to dirListItemChanged() !
     if (_current == i) {
-        _current = 0;
+        _current = nullptr;
         update();
     }
 }