diff --git a/documentation/documentationfindwidget.h b/documentation/documentationfindwidget.h
--- a/documentation/documentationfindwidget.h
+++ b/documentation/documentationfindwidget.h
@@ -39,7 +39,7 @@
         };
         Q_DECLARE_FLAGS(FindOptions, FindOption);
         
-        explicit DocumentationFindWidget(QWidget* parent = 0);
+        explicit DocumentationFindWidget(QWidget* parent = nullptr);
         virtual ~DocumentationFindWidget();
         
         virtual void showEvent ( QShowEvent* ) override;
diff --git a/interfaces/idocumentation.h b/interfaces/idocumentation.h
--- a/interfaces/idocumentation.h
+++ b/interfaces/idocumentation.h
@@ -57,7 +57,7 @@
             inside the documentation widget. The implementation will have to enable the
             widget if it means to support the search feature.
     */
-    virtual QWidget* documentationWidget(DocumentationFindWidget* findWidget, QWidget* parent=0) = 0;
+    virtual QWidget* documentationWidget(DocumentationFindWidget* findWidget, QWidget* parent = nullptr) = 0;
 
     virtual IDocumentationProvider* provider() const = 0;
 
diff --git a/interfaces/iplugincontroller.h b/interfaces/iplugincontroller.h
--- a/interfaces/iplugincontroller.h
+++ b/interfaces/iplugincontroller.h
@@ -161,7 +161,7 @@
         if (plugin) {
             return plugin->extension<Extension>();
         }
-        return 0L;
+        return nullptr;
     }
 
     /**
diff --git a/interfaces/iuicontroller.h b/interfaces/iuicontroller.h
--- a/interfaces/iuicontroller.h
+++ b/interfaces/iuicontroller.h
@@ -51,7 +51,7 @@
      * @param parent the parent to use as parent for the widget
      * @returns the new widget for the toolview
      */
-    virtual QWidget* create(QWidget *parent = 0) = 0;
+    virtual QWidget* create(QWidget *parent = nullptr) = 0;
     /** 
      * @returns the identifier of this toolview.  The identifier
      * is used to remember which areas the tool view should appear
diff --git a/language/duchain/appendedlist.h b/language/duchain/appendedlist.h
--- a/language/duchain/appendedlist.h
+++ b/language/duchain/appendedlist.h
@@ -121,14 +121,14 @@
           //The only function that does not lock the mutex is getItem(..), because that function must be very efficient.
           //Since it's only a few instructions from the moment m_items is read to the moment it's used,
           //deleting the old data after a few seconds should be safe.
-          m_deleteLater.append(qMakePair(time(0), oldItems));
+          m_deleteLater.append(qMakePair(time(nullptr), oldItems));
 
           //We do this in this place so it isn't called too often. The result is that we will always have some additional data around.
           //However the index itself should anyway not consume too much data.
           if(!m_deleteLater.isEmpty()) {
             while(!m_deleteLater.isEmpty()) {
               //We delete after 5 seconds
-              if(time(0) - m_deleteLater.first().first > 5) {
+              if(time(nullptr) - m_deleteLater.first().first > 5) {
                 m_deleteLater.removeFirst();
               }else{
                 break;
@@ -296,7 +296,7 @@
 #define APPENDED_LIST_FIRST(container, type, name) \
     APPENDED_LIST_COMMON(container, type, name) \
     const type* name() const { \
-      if((name ## Data & KDevelop::DynamicAppendedListRevertMask) == 0) return 0; \
+      if((name ## Data & KDevelop::DynamicAppendedListRevertMask) == 0) return nullptr; \
       if(!appendedListsDynamic()) return reinterpret_cast<const type*>(reinterpret_cast<const char*>(this) + classSize() + offsetBehindBase()); \
       else return temporaryHash ## container ## name().getItem(name ## Data).data(); \
     } \
@@ -309,7 +309,7 @@
 #define APPENDED_LIST(container, type, name, predecessor) \
     APPENDED_LIST_COMMON(container, type, name) \
     const type* name() const {\
-      if((name ## Data & KDevelop::DynamicAppendedListRevertMask) == 0) return 0; \
+      if((name ## Data & KDevelop::DynamicAppendedListRevertMask) == 0) return nullptr; \
       if(!appendedListsDynamic()) return reinterpret_cast<const type*>(reinterpret_cast<const char*>(this) + classSize() + predecessor ## OffsetBehind()); \
       else return temporaryHash ## container ## name().getItem(name ## Data).data(); \
     } \
diff --git a/language/duchain/classdeclaration.h b/language/duchain/classdeclaration.h
--- a/language/duchain/classdeclaration.h
+++ b/language/duchain/classdeclaration.h
@@ -112,7 +112,7 @@
   /**Returns whether base is a public base-class of this class
    * @param baseConversionLevels If nonzero, this will count the distance of the classes.
    * */
-  bool isPublicBaseClass( ClassDeclaration* base, const KDevelop::TopDUContext* topContext, int* baseConversionLevels  = 0 ) const;
+  bool isPublicBaseClass( ClassDeclaration* base, const KDevelop::TopDUContext* topContext, int* baseConversionLevels = nullptr ) const;
 
   QString toString() const override;
 
diff --git a/language/duchain/duchainlock.h b/language/duchain/duchainlock.h
--- a/language/duchain/duchainlock.h
+++ b/language/duchain/duchainlock.h
@@ -115,7 +115,7 @@
    * \param duChainLock lock to read-acquire. If this is left zero, DUChain::lock() is used.
    * \param timeout Timeout in milliseconds. If this is not zero, you've got to check locked() to see whether the lock succeeded.
    */
-  explicit DUChainReadLocker(DUChainLock* duChainLock = 0, unsigned int timeout = 0);
+  explicit DUChainReadLocker(DUChainLock* duChainLock = nullptr, unsigned int timeout = 0);
 
   /// Destructor.
   ~DUChainReadLocker();
@@ -147,7 +147,7 @@
    * \param duChainLock lock to write-acquire. If this is left zero, DUChain::lock() is used.
    * \param timeout Timeout in milliseconds. If this is not zero, you've got to check locked() to see whether the lock succeeded.
    */
-  explicit DUChainWriteLocker(DUChainLock* duChainLock = 0, unsigned int timeout = 0);
+  explicit DUChainWriteLocker(DUChainLock* duChainLock = nullptr, unsigned int timeout = 0);
   /// Destructor.
   ~DUChainWriteLocker();
 
diff --git a/language/duchain/duchainpointer.h b/language/duchain/duchainpointer.h
--- a/language/duchain/duchainpointer.h
+++ b/language/duchain/duchainpointer.h
@@ -159,15 +159,15 @@
 
     Type* data() const {
       if( !d )
-        return 0;
+        return nullptr;
       return static_cast<Type*>(d->base());
     }
 
     DUChainPointer<Type>& operator= ( Type* rhs ) {
       if( rhs )
         d = rhs->weakPointer();
       else
-        d = 0;
+        d = nullptr;
 
       return *this;
     }
diff --git a/language/duchain/duchainregister.h b/language/duchain/duchainregister.h
--- a/language/duchain/duchainregister.h
+++ b/language/duchain/duchainregister.h
@@ -117,7 +117,7 @@
       Q_ASSERT(m_factories.size() > T::Identity);
       Q_ASSERT(m_factories[T::Identity]);
       delete m_factories[T::Identity];
-      m_factories[T::Identity] = 0;
+      m_factories[T::Identity] = nullptr;
       m_dataClassSizes[T::Identity] = 0;
     }
 
diff --git a/language/duchain/duchainutils.h b/language/duchain/duchainutils.h
--- a/language/duchain/duchainutils.h
+++ b/language/duchain/duchainutils.h
@@ -79,7 +79,7 @@
   KDEVPLATFORMLANGUAGE_EXPORT ItemUnderCursor itemUnderCursor(const QUrl& url, const KTextEditor::Cursor& cursor);
   /**If the given declaration is a definition, and has a real declaration
     *attached, returns that declarations. Else returns the given argument. */
-  KDEVPLATFORMLANGUAGE_EXPORT Declaration* declarationForDefinition(Declaration* definition, TopDUContext* topContext = 0);
+  KDEVPLATFORMLANGUAGE_EXPORT Declaration* declarationForDefinition(Declaration* definition, TopDUContext* topContext = nullptr);
   ///Returns the first declaration in the given line. Searches the given context and all sub-contexts.
   ///Must only be called from the foreground or with the foreground lock held.
   KDEVPLATFORMLANGUAGE_EXPORT Declaration* declarationInLine(const KTextEditor::Cursor& cursor, KDevelop::DUContext* ctx);
diff --git a/language/duchain/functiondefinition.h b/language/duchain/functiondefinition.h
--- a/language/duchain/functiondefinition.h
+++ b/language/duchain/functiondefinition.h
@@ -44,7 +44,7 @@
     * @param topContext the top-context from which to search
     * \returns the declaration matching this definition, otherwise null if no matching declaration has been found.
     * */
-    Declaration* declaration(const TopDUContext* topContext = 0) const;
+    Declaration* declaration(const TopDUContext* topContext = nullptr) const;
 
     ///Returns true if a Declaration has been assigned to this Definition
     bool hasDeclaration() const;
diff --git a/language/duchain/indexeddeclaration.h b/language/duchain/indexeddeclaration.h
--- a/language/duchain/indexeddeclaration.h
+++ b/language/duchain/indexeddeclaration.h
@@ -33,7 +33,7 @@
  */
 class KDEVPLATFORMLANGUAGE_EXPORT IndexedDeclaration {
   public:
-    IndexedDeclaration(const Declaration* decl = 0);
+    IndexedDeclaration(const Declaration* decl = nullptr);
     IndexedDeclaration(uint topContext, uint declarationIndex);
 
     /**
@@ -60,7 +60,7 @@
 
     ///@warning The duchain needs to be locked when this is called
     inline bool isValid() const {
-      return !isDummy() && declaration() != 0;
+      return !isDummy() && declaration() != nullptr;
     }
 
     inline bool operator<(const IndexedDeclaration& rhs) const {
diff --git a/language/duchain/indexedducontext.h b/language/duchain/indexedducontext.h
--- a/language/duchain/indexedducontext.h
+++ b/language/duchain/indexedducontext.h
@@ -55,7 +55,7 @@
     }
 
     bool isValid() const {
-      return !isDummy() && context() != 0;
+      return !isDummy() && context() != nullptr;
     }
 
     bool operator<(const IndexedDUContext& rhs) const {
diff --git a/language/duchain/indexedtopducontext.h b/language/duchain/indexedtopducontext.h
--- a/language/duchain/indexedtopducontext.h
+++ b/language/duchain/indexedtopducontext.h
@@ -40,7 +40,7 @@
       if(!index)
         setIsDummy(true);
     }
-    IndexedTopDUContext(TopDUContext* context = 0);
+    IndexedTopDUContext(TopDUContext* context = nullptr);
 
     enum {
       DummyMask = 1u<<31u
diff --git a/language/duchain/localindexeddeclaration.h b/language/duchain/localindexeddeclaration.h
--- a/language/duchain/localindexeddeclaration.h
+++ b/language/duchain/localindexeddeclaration.h
@@ -33,7 +33,7 @@
 class KDEVPLATFORMLANGUAGE_EXPORT LocalIndexedDeclaration
 {
   public:
-    LocalIndexedDeclaration(Declaration* decl = 0);
+    LocalIndexedDeclaration(Declaration* decl = nullptr);
     LocalIndexedDeclaration(uint declarationIndex);
 
     /**
diff --git a/language/duchain/navigation/navigationaction.h b/language/duchain/navigation/navigationaction.h
--- a/language/duchain/navigation/navigationaction.h
+++ b/language/duchain/navigation/navigationaction.h
@@ -42,16 +42,16 @@
   };
 
   ///When executed, this navigation-action calls the "executeKeyAction(QString) function in its navigation-context
-  NavigationAction(QString _key) : targetContext(0), type(ExecuteKey), key(_key) {
+  NavigationAction(QString _key) : targetContext(nullptr), type(ExecuteKey), key(_key) {
   }
 
-  NavigationAction() : targetContext(0), type(None) {
+  NavigationAction() : targetContext(nullptr), type(None) {
   }
 
-  NavigationAction( DeclarationPointer decl_, Type type_ ) : targetContext(0), decl(decl_), type(type_) {
+  NavigationAction( DeclarationPointer decl_, Type type_ ) : targetContext(nullptr), decl(decl_), type(type_) {
   }
 
-  NavigationAction( const QUrl& _document, const KTextEditor::Cursor& _cursor) : targetContext(0), document(_document), cursor(_cursor) {
+  NavigationAction( const QUrl& _document, const KTextEditor::Cursor& _cursor) : targetContext(nullptr), document(_document), cursor(_cursor) {
     type = JumpToSource;
   }
 
diff --git a/language/duchain/parsingenvironment.h b/language/duchain/parsingenvironment.h
--- a/language/duchain/parsingenvironment.h
+++ b/language/duchain/parsingenvironment.h
@@ -142,7 +142,7 @@
     ///Can additionally use language-specific information to decide whether the top-context that has this data attached needs to be reparsed.
     ///The standard-implementation checks the modification-time of this file stored using setModificationRevision, and all other modification-times
     ///stored with addModificationRevision(..).
-    virtual bool needsUpdate(const ParsingEnvironment* environment = 0) const;
+    virtual bool needsUpdate(const ParsingEnvironment* environment = nullptr) const;
     
     /**
      * A language-specific flag used by C++ to mark one context as a proxy of another.
diff --git a/language/duchain/topducontext.h b/language/duchain/topducontext.h
--- a/language/duchain/topducontext.h
+++ b/language/duchain/topducontext.h
@@ -58,7 +58,7 @@
 ///keep a ReferencedTopDUContext.
 class KDEVPLATFORMLANGUAGE_EXPORT ReferencedTopDUContext {
   public:
-    ReferencedTopDUContext(TopDUContext* context = 0);
+    ReferencedTopDUContext(TopDUContext* context = nullptr);
     ReferencedTopDUContext(const ReferencedTopDUContext& rhs);
     ~ReferencedTopDUContext();
     
@@ -107,7 +107,7 @@
 class KDEVPLATFORMLANGUAGE_EXPORT TopDUContext : public DUContext
 {
 public:
-  explicit TopDUContext(const IndexedString& url, const RangeInRevision& range, ParsingEnvironmentFile* file = 0);
+  explicit TopDUContext(const IndexedString& url, const RangeInRevision& range, ParsingEnvironmentFile* file = nullptr);
   explicit TopDUContext(TopDUContextData& data);
 
   TopDUContext* topContext() const override;
diff --git a/language/duchain/topducontextutils.h b/language/duchain/topducontextutils.h
--- a/language/duchain/topducontextutils.h
+++ b/language/duchain/topducontextutils.h
@@ -27,7 +27,7 @@
 /// \todo move data to private d pointer classes
 struct KDEVPLATFORMLANGUAGE_EXPORT TopDUContext::DeclarationChecker
 {
-  DeclarationChecker(const TopDUContext* _top, const CursorInRevision& _position, const AbstractType::Ptr& _dataType, DUContext::SearchFlags _flags, KDevVarLengthArray<IndexedDeclaration>* _createVisibleCache = 0);
+  DeclarationChecker(const TopDUContext* _top, const CursorInRevision& _position, const AbstractType::Ptr& _dataType, DUContext::SearchFlags _flags, KDevVarLengthArray<IndexedDeclaration>* _createVisibleCache = nullptr);
   bool operator()(const Declaration* dec) const;
 
   mutable KDevVarLengthArray<IndexedDeclaration>* createVisibleCache;
diff --git a/language/duchain/types/arraytype.h b/language/duchain/types/arraytype.h
--- a/language/duchain/types/arraytype.h
+++ b/language/duchain/types/arraytype.h
@@ -98,7 +98,7 @@
 template<>
 inline ArrayType* fastCast<ArrayType*>(AbstractType* from) {
   if(!from || from->whichType() != AbstractType::TypeArray)
-    return 0;
+    return nullptr;
   else
     return static_cast<ArrayType*>(from);
 }
diff --git a/language/duchain/types/constantintegraltype.h b/language/duchain/types/constantintegraltype.h
--- a/language/duchain/types/constantintegraltype.h
+++ b/language/duchain/types/constantintegraltype.h
@@ -110,7 +110,7 @@
 template<>
 inline ConstantIntegralType* fastCast<ConstantIntegralType*>(AbstractType* from) {
   if(!from || from->whichType() != KDevelop::AbstractType::TypeIntegral)
-    return 0;
+    return nullptr;
   else
     return dynamic_cast<ConstantIntegralType*>(from);
 }
diff --git a/language/duchain/types/delayedtype.h b/language/duchain/types/delayedtype.h
--- a/language/duchain/types/delayedtype.h
+++ b/language/duchain/types/delayedtype.h
@@ -97,7 +97,7 @@
 template<>
 inline DelayedType* fastCast<DelayedType*>(AbstractType* from) {
   if(!from || from->whichType() != AbstractType::TypeDelayed)
-    return 0;
+    return nullptr;
   else
     return static_cast<DelayedType*>(from);
 }
diff --git a/language/duchain/types/enumerationtype.h b/language/duchain/types/enumerationtype.h
--- a/language/duchain/types/enumerationtype.h
+++ b/language/duchain/types/enumerationtype.h
@@ -65,7 +65,7 @@
 template<>
 inline EnumerationType* fastCast<EnumerationType*>(AbstractType* from) {
   if(!from || from->whichType() != KDevelop::AbstractType::TypeEnumeration)
-    return 0;
+    return nullptr;
   else
     return static_cast<EnumerationType*>(from);
 }
diff --git a/language/duchain/types/enumeratortype.h b/language/duchain/types/enumeratortype.h
--- a/language/duchain/types/enumeratortype.h
+++ b/language/duchain/types/enumeratortype.h
@@ -67,7 +67,7 @@
 template<>
 inline EnumeratorType* fastCast<EnumeratorType*>(AbstractType* from) {
   if(!from || from->whichType() != KDevelop::AbstractType::TypeEnumerator)
-    return 0;
+    return nullptr;
   else
     return static_cast<EnumeratorType*>(from);
 }
diff --git a/language/duchain/types/functiontype.h b/language/duchain/types/functiontype.h
--- a/language/duchain/types/functiontype.h
+++ b/language/duchain/types/functiontype.h
@@ -139,7 +139,7 @@
 template<>
 inline FunctionType* fastCast<FunctionType*>(AbstractType* from) {
   if(!from || from->whichType() != AbstractType::TypeFunction)
-    return 0;
+    return nullptr;
   else
     return static_cast<FunctionType*>(from);
 }
diff --git a/language/duchain/types/integraltype.h b/language/duchain/types/integraltype.h
--- a/language/duchain/types/integraltype.h
+++ b/language/duchain/types/integraltype.h
@@ -118,7 +118,7 @@
 template<>
 inline IntegralType* fastCast<IntegralType*>(AbstractType* from) {
   if(!from || from->whichType() != AbstractType::TypeIntegral)
-    return 0;
+    return nullptr;
   else
     return static_cast<IntegralType*>(from);
 }
diff --git a/language/duchain/types/pointertype.h b/language/duchain/types/pointertype.h
--- a/language/duchain/types/pointertype.h
+++ b/language/duchain/types/pointertype.h
@@ -88,7 +88,7 @@
 template<>
 inline PointerType* fastCast<PointerType*>(AbstractType* from) {
   if(!from || from->whichType() != AbstractType::TypePointer)
-    return 0;
+    return nullptr;
   else
     return static_cast<PointerType*>(from);
 }
diff --git a/language/duchain/types/referencetype.h b/language/duchain/types/referencetype.h
--- a/language/duchain/types/referencetype.h
+++ b/language/duchain/types/referencetype.h
@@ -102,7 +102,7 @@
 template<>
 inline ReferenceType* fastCast<ReferenceType*>(AbstractType* from) {
   if(!from || from->whichType() != AbstractType::TypeReference)
-    return 0;
+    return nullptr;
   else
     return static_cast<ReferenceType*>(from);
 }
diff --git a/language/duchain/types/structuretype.h b/language/duchain/types/structuretype.h
--- a/language/duchain/types/structuretype.h
+++ b/language/duchain/types/structuretype.h
@@ -77,7 +77,7 @@
 template<>
 inline StructureType* fastCast<StructureType*>(AbstractType* from) {
   if(!from || from->whichType() != AbstractType::TypeStructure)
-    return 0;
+    return nullptr;
   else
     return static_cast<StructureType*>(from);
 }
diff --git a/language/duchain/types/typealiastype.h b/language/duchain/types/typealiastype.h
--- a/language/duchain/types/typealiastype.h
+++ b/language/duchain/types/typealiastype.h
@@ -76,7 +76,7 @@
 template<>
 inline TypeAliasType* fastCast<TypeAliasType*>(AbstractType* from) {
   if(!from || from->whichType() != AbstractType::TypeIntegral)
-    return 0;
+    return nullptr;
   else
     return static_cast<TypeAliasType*>(from);
 }
diff --git a/language/duchain/types/typepointer.h b/language/duchain/types/typepointer.h
--- a/language/duchain/types/typepointer.h
+++ b/language/duchain/types/typepointer.h
@@ -48,7 +48,7 @@
 
     ///Uses dynamic_cast to cast this pointer to the given type
     template<class U>
-    TypePtr<U> cast(U * /*dummy*/ = 0) const {
+    TypePtr<U> cast(U * /*dummy*/ = nullptr) const {
       return TypePtr<U>(dynamic_cast<U*>(Base::data()));
     }
 
diff --git a/language/duchain/types/typeutils.h b/language/duchain/types/typeutils.h
--- a/language/duchain/types/typeutils.h
+++ b/language/duchain/types/typeutils.h
@@ -41,12 +41,12 @@
    * Modifiers of aliases ore references are pushed into the targets.
    * @return return-value will only be zero if type is zero
    */
-  KDEVPLATFORMLANGUAGE_EXPORT KDevelop::AbstractType::Ptr targetType(const KDevelop::AbstractType::Ptr& type, const KDevelop::TopDUContext* topContext, bool* constant = 0);
+  KDEVPLATFORMLANGUAGE_EXPORT KDevelop::AbstractType::Ptr targetType(const KDevelop::AbstractType::Ptr& type, const KDevelop::TopDUContext* topContext, bool* constant = nullptr);
   /**
    * Same as targetType(..), ecept that it does not un-aliases TypeAliasTypes
    * Modifiers of aliases ore references are pushed into the targets.
    */
-  KDEVPLATFORMLANGUAGE_EXPORT KDevelop::AbstractType::Ptr targetTypeKeepAliases(const KDevelop::AbstractType::Ptr& type, const KDevelop::TopDUContext* topContext, bool* constant = 0);
+  KDEVPLATFORMLANGUAGE_EXPORT KDevelop::AbstractType::Ptr targetTypeKeepAliases(const KDevelop::AbstractType::Ptr& type, const KDevelop::TopDUContext* topContext, bool* constant = nullptr);
   /**
    * Resolves all type-aliases, returning the effective aliased type
    * All modifiers are pushed from the aliases into the targets.
diff --git a/language/util/basicsetrepository.h b/language/util/basicsetrepository.h
--- a/language/util/basicsetrepository.h
+++ b/language/util/basicsetrepository.h
@@ -291,7 +291,7 @@
       if(index)
           return dataRepository.itemFromIndex(index);
       else
-          return 0;
+          return nullptr;
   }
   
   inline QMutex* mutex() const {
diff --git a/language/util/setrepository.h b/language/util/setrepository.h
--- a/language/util/setrepository.h
+++ b/language/util/setrepository.h
@@ -108,14 +108,14 @@
             if(m_data->leftNode())
                 return StaticRepository::repository()->nodeFromIndex(m_data->leftNode());
             else
-                return 0;
+                return nullptr;
         }
 
         inline VirtualSetNode<T, Conversion, StaticRepository> rightChild() const {
             if(m_data->rightNode())
                 return StaticRepository::repository()->nodeFromIndex(m_data->rightNode());
             else
-                return 0;
+                return nullptr;
         }
 
         ///Returns the start of this node's range. If this is a final node, the length of the range is 1.
diff --git a/plugins/appwizard/appwizarddialog.h b/plugins/appwizard/appwizarddialog.h
--- a/plugins/appwizard/appwizarddialog.h
+++ b/plugins/appwizard/appwizarddialog.h
@@ -44,7 +44,7 @@
 Q_OBJECT
 public:
     AppWizardDialog( KDevelop::IPluginController*, ProjectTemplatesModel*,
-                     QWidget *parent = 0, Qt::WindowFlags flags = 0);
+                     QWidget *parent = nullptr, Qt::WindowFlags flags = nullptr);
 
     ApplicationInfo appInfo() const;
 
diff --git a/plugins/appwizard/appwizardpagewidget.h b/plugins/appwizard/appwizardpagewidget.h
--- a/plugins/appwizard/appwizardpagewidget.h
+++ b/plugins/appwizard/appwizardpagewidget.h
@@ -26,7 +26,7 @@
 {
     Q_OBJECT
 public:
-    explicit AppWizardPageWidget(QWidget* parent = 0);
+    explicit AppWizardPageWidget(QWidget* parent = nullptr);
     virtual ~AppWizardPageWidget();
 
     virtual bool shouldContinue();
diff --git a/plugins/filetemplates/templateclassassistant.cpp b/plugins/filetemplates/templateclassassistant.cpp
--- a/plugins/filetemplates/templateclassassistant.cpp
+++ b/plugins/filetemplates/templateclassassistant.cpp
@@ -58,17 +58,17 @@
 #include <KIO/Global>
 #include <KLocalizedString>
 
-#define REMOVE_PAGE(name)       \
-if (d->name##Page)              \
-{                               \
-    removePage(d->name##Page);  \
-    d->name##Page = 0;          \
-    d->name##PageWidget = 0;    \
+#define REMOVE_PAGE(name)          \
+if (d->name##Page)                 \
+{                                  \
+    removePage(d->name##Page);     \
+    d->name##Page = nullptr;       \
+    d->name##PageWidget = nullptr; \
 }
 
-#define ZERO_PAGE(name)         \
-d->name##Page = 0;              \
-d->name##PageWidget = 0;
+#define ZERO_PAGE(name)  \
+d->name##Page = nullptr; \
+d->name##PageWidget = nullptr;
 
 using namespace KDevelop;
 
diff --git a/plugins/subversion/kdevsvncpp/client.hpp b/plugins/subversion/kdevsvncpp/client.hpp
--- a/plugins/subversion/kdevsvncpp/client.hpp
+++ b/plugins/subversion/kdevsvncpp/client.hpp
@@ -112,7 +112,7 @@
     /**
      * Initializes the primary memory pool.
      */
-    Client(Context * context = 0);
+    Client(Context * context = nullptr);
 
     virtual ~Client();
 
diff --git a/plugins/subversion/kdevsvncpp/entry.hpp b/plugins/subversion/kdevsvncpp/entry.hpp
--- a/plugins/subversion/kdevsvncpp/entry.hpp
+++ b/plugins/subversion/kdevsvncpp/entry.hpp
@@ -50,7 +50,7 @@
      *
      * @param src another entry to copy from
      */
-    Entry(const svn_wc_entry_t * src = 0);
+    Entry(const svn_wc_entry_t * src = nullptr);
 
     /**
      * copy constructor
diff --git a/plugins/subversion/kdevsvncpp/info.hpp b/plugins/subversion/kdevsvncpp/info.hpp
--- a/plugins/subversion/kdevsvncpp/info.hpp
+++ b/plugins/subversion/kdevsvncpp/info.hpp
@@ -49,7 +49,7 @@
      *
      * @param src another entry to copy from
      */
-    Info(const Path & path, const svn_info_t * src = 0);
+    Info(const Path & path, const svn_info_t * src = nullptr);
 
     /**
      * copy constructor
diff --git a/plugins/subversion/kdevsvncpp/pool.hpp b/plugins/subversion/kdevsvncpp/pool.hpp
--- a/plugins/subversion/kdevsvncpp/pool.hpp
+++ b/plugins/subversion/kdevsvncpp/pool.hpp
@@ -41,7 +41,7 @@
      *
      * @param parent NULL -> global pool
      */
-    Pool(apr_pool_t * parent = (apr_pool_t *)0);
+    Pool(apr_pool_t * parent = nullptr);
 
     virtual ~ Pool();
 
diff --git a/plugins/subversion/kdevsvncpp/property.hpp b/plugins/subversion/kdevsvncpp/property.hpp
--- a/plugins/subversion/kdevsvncpp/property.hpp
+++ b/plugins/subversion/kdevsvncpp/property.hpp
@@ -64,7 +64,7 @@
   class Property
   {
   public:
-    Property(Context * context = 0,
+    Property(Context * context = nullptr,
              const Path & path = "");
 
     virtual ~Property();
diff --git a/plugins/subversion/kdevsvncpp/status.hpp b/plugins/subversion/kdevsvncpp/status.hpp
--- a/plugins/subversion/kdevsvncpp/status.hpp
+++ b/plugins/subversion/kdevsvncpp/status.hpp
@@ -50,7 +50,7 @@
      * @param path
      * @param status
      */
-    Status(const char * path = 0, const svn_wc_status2_t * status = 0);
+    Status(const char * path = nullptr, const svn_wc_status2_t * status = nullptr);
 
     /**
      * copy constructor
diff --git a/plugins/subversion/kdevsvncpp/targets.hpp b/plugins/subversion/kdevsvncpp/targets.hpp
--- a/plugins/subversion/kdevsvncpp/targets.hpp
+++ b/plugins/subversion/kdevsvncpp/targets.hpp
@@ -64,7 +64,7 @@
      *
      * @param target
      */
-    Targets(const char * target = 0);
+    Targets(const char * target = nullptr);
 
     /**
      * Copy Constructor
diff --git a/serialization/itemrepository.h b/serialization/itemrepository.h
--- a/serialization/itemrepository.h
+++ b/serialization/itemrepository.h
@@ -130,12 +130,12 @@
     Bucket()
       : m_monsterBucketExtent(0)
       , m_available(0)
-      , m_data(0)
-      , m_mappedData(0)
-      , m_objectMap(0)
+      , m_data(nullptr)
+      , m_mappedData(nullptr)
+      , m_objectMap(nullptr)
       , m_largestFreeItem(0)
       , m_freeItemCount(0)
-      , m_nextBucketHash(0)
+      , m_nextBucketHash(nullptr)
       , m_dirty(false)
       , m_changed(false)
       , m_lastUsed(0)
@@ -214,7 +214,7 @@
 
       if(static_cast<size_t>(file->pos()) != offset + (1+m_monsterBucketExtent)*DataSize)
       {
-        KMessageBox::error(0, i18n("Failed writing to %1, probably the disk is full", file->fileName()));
+        KMessageBox::error(nullptr, i18n("Failed writing to %1, probably the disk is full", file->fileName()));
         abort();
       }
 
@@ -1013,7 +1013,7 @@
     DynamicItem(const DynamicItem& rhs) : m_item(rhs.m_item), m_start(rhs.m_start) {
 //         qDebug() << "stealing" << m_item;
       Q_ASSERT(rhs.m_start);
-      rhs.m_start = 0;
+      rhs.m_start = nullptr;
     }
 
     Item* operator->() {
@@ -1057,20 +1057,20 @@
   ///                If this is zero, you have to care about storing the data using store() and/or close() by yourself. It does not happen automatically.
   ///                For the global standard registry, the storing/loading is triggered from within duchain, so you don't need to care about it.
   ItemRepository(const QString& repositoryName, ItemRepositoryRegistry* registry  = &globalItemRepositoryRegistry(),
-                 uint repositoryVersion = 1, AbstractRepositoryManager* manager = 0)
+                 uint repositoryVersion = 1, AbstractRepositoryManager* manager = nullptr)
     : m_ownMutex(QMutex::Recursive)
     , m_mutex(&m_ownMutex)
     , m_repositoryName(repositoryName)
     , m_registry(registry)
-    , m_file(0)
-    , m_dynamicFile(0)
+    , m_file(nullptr)
+    , m_dynamicFile(nullptr)
     , m_repositoryVersion(repositoryVersion)
     , m_manager(manager)
   {
     m_unloadingEnabled = true;
     m_metaDataChanged = true;
     m_buckets.resize(10);
-    m_buckets.fill(0);
+    m_buckets.fill(nullptr);
 
     memset(m_firstBucketForHash, 0, bucketHashSize * sizeof(short unsigned int));
 
@@ -1695,7 +1695,7 @@
             const int unloadAfterTicks = 2;
             if(m_buckets[a]->lastUsed() > unloadAfterTicks) {
                 delete m_buckets[a];
-                m_buckets[a] = 0;
+                m_buckets[a] = nullptr;
             }else{
                 m_buckets[a]->tick();
             }
@@ -1910,9 +1910,9 @@
     m_dynamicFile = new QFile(dir.absoluteFilePath( m_repositoryName + QLatin1String("_dynamic") ));
     if(!m_file->open( QFile::ReadWrite ) || !m_dynamicFile->open( QFile::ReadWrite ) ) {
       delete m_file;
-      m_file = 0;
+      m_file = nullptr;
       delete m_dynamicFile;
-      m_dynamicFile = 0;
+      m_dynamicFile = nullptr;
       return false;
     }
 
@@ -1932,7 +1932,7 @@
       m_file->write((char*)&m_statItemCount, sizeof(uint));
 
       m_buckets.resize(10);
-      m_buckets.fill(0);
+      m_buckets.fill(nullptr);
       uint bucketCount = m_buckets.size();
       m_file->write((char*)&bucketCount, sizeof(uint));
 
@@ -1944,7 +1944,7 @@
       //We have completely initialized the file now
       if(m_file->pos() != BucketStartOffset)
       {
-        KMessageBox::error(0, i18n("Failed writing to %1, probably the disk is full", m_file->fileName()));
+        KMessageBox::error(nullptr, i18n("Failed writing to %1, probably the disk is full", m_file->fileName()));
         abort();
       }
 
@@ -1967,9 +1967,9 @@
       if(storedVersion != m_repositoryVersion || hashSize != bucketHashSize || itemRepositoryVersion != staticItemRepositoryVersion()) {
         qDebug() << "repository" << m_repositoryName << "version mismatch in" << m_file->fileName() << ", stored: version " << storedVersion << "hashsize" << hashSize << "repository-version" << itemRepositoryVersion << " current: version" << m_repositoryVersion << "hashsize" << bucketHashSize << "repository-version" << staticItemRepositoryVersion();
         delete m_file;
-        m_file = 0;
+        m_file = nullptr;
         delete m_dynamicFile;
-        m_dynamicFile = 0;
+        m_dynamicFile = nullptr;
         return false;
       }
       m_metaDataChanged = false;
@@ -1990,7 +1990,7 @@
     }
 
     m_fileMapSize = 0;
-    m_fileMap = 0;
+    m_fileMap = nullptr;
 
 #ifdef ITEMREPOSITORY_USE_MMAP_LOADING
     if(m_file->size() > BucketStartOffset){
@@ -2020,14 +2020,14 @@
     if(m_file)
       m_file->close();
     delete m_file;
-    m_file = 0;
-    m_fileMap = 0;
+    m_file = nullptr;
+    m_fileMap = nullptr;
     m_fileMapSize = 0;
 
     if(m_dynamicFile)
       m_dynamicFile->close();
     delete m_dynamicFile;
-    m_dynamicFile = 0;
+    m_dynamicFile = nullptr;
 
     qDeleteAll(m_buckets);
     m_buckets.clear();
@@ -2136,7 +2136,7 @@
     Q_ASSERT(bucketForIndex(bucketNumber)->isEmpty());
     Q_ASSERT(bucketForIndex(bucketNumber)->noNextBuckets());
     delete m_buckets[bucketNumber];
-    m_buckets[bucketNumber] = 0;
+    m_buckets[bucketNumber] = nullptr;
   }
 
   //m_file must be opened
diff --git a/serialization/repositorymanager.h b/serialization/repositorymanager.h
--- a/serialization/repositorymanager.h
+++ b/serialization/repositorymanager.h
@@ -32,7 +32,7 @@
   ///@param shareMutex Option repository from where this repository should take the thread-safety mutex
   RepositoryManager(QString name,
                     int version = 1,
-                    AbstractRepositoryManager*(*shareMutex)() = 0,
+                    AbstractRepositoryManager*(*shareMutex)() = nullptr,
                     ItemRepositoryRegistry& registry = globalItemRepositoryRegistry()) :
   m_name(name),
   m_version(version),
diff --git a/shell/core.h b/shell/core.h
--- a/shell/core.h
+++ b/shell/core.h
@@ -63,7 +63,7 @@
       * @param session the name or uuid of the session to be loaded
       *
       */
-    static bool initialize(QObject* splash = 0, Setup mode=Default, const QString& session = {} );
+    static bool initialize(QObject* splash = nullptr, Setup mode=Default, const QString& session = {} );
 
     /**
      * \brief Provide access an instance of Core
@@ -123,11 +123,11 @@
 
 protected:
     friend class CorePrivate;
-    Core( KDevelop::CorePrivate* dd, QObject* parent = 0 );
+    Core( KDevelop::CorePrivate* dd, QObject* parent = nullptr );
     KDevelop::CorePrivate *d;
     static Core *m_self;
 private:
-    Core(QObject *parent = 0);
+    Core(QObject *parent = nullptr);
 };
 
 }
diff --git a/sublime/areaindex.h b/sublime/areaindex.h
--- a/sublime/areaindex.h
+++ b/sublime/areaindex.h
@@ -126,7 +126,7 @@
     Does nothing if the view is already split.
     @param after if not 0, new view will be placed after this one.
     @param view the view to be added.*/
-    void add(View *view, View *after = 0);
+    void add(View *view, View *after = nullptr);
     /**Removes view and unsplits the parent index when no views
     are left at the current index.*/
     void remove(View *view);
diff --git a/tests/json/jsondeclarationtests.h b/tests/json/jsondeclarationtests.h
--- a/tests/json/jsondeclarationtests.h
+++ b/tests/json/jsondeclarationtests.h
@@ -182,7 +182,7 @@
   const QString UN_ID_ERROR = QStringLiteral("Unable to identify declaration of type \"%1\".");
   AbstractType::Ptr type = TypeUtils::targetType(decl->abstractType(), decl->topContext());
   IdentifiedType* idType = dynamic_cast<IdentifiedType*>(type.data());
-  Declaration* idDecl = idType ? idType->declaration(decl->topContext()) : 0;
+  Declaration* idDecl = idType ? idType->declaration(decl->topContext()) : nullptr;
   if (!idDecl)
     return UN_ID_ERROR.arg(type->toString());
 
@@ -238,7 +238,7 @@
 DeclarationTest(definition)
 {
   KDevVarLengthArray<IndexedDeclaration> definitions = DUChain::definitions()->definitions(decl->id());
-  Declaration *declDef  = 0;
+  Declaration *declDef = nullptr;
   if (!definitions.isEmpty())
     declDef = definitions.at(0).declaration();
   return testObject(declDef, value, QStringLiteral("Declaration's definition"));
@@ -257,7 +257,7 @@
 ///@returns whether the declaration's nullity matches the given value
 DeclarationTest(null)
 {
-  return compareValues(decl == 0, value, QStringLiteral("Declaration's nullity"));
+  return compareValues(decl == nullptr, value, QStringLiteral("Declaration's nullity"));
 }
 ///JSON type: bool
 ///@returns whether the declaration's default parameter matches the given value
diff --git a/util/convenientfreelist.h b/util/convenientfreelist.h
--- a/util/convenientfreelist.h
+++ b/util/convenientfreelist.h
@@ -36,7 +36,7 @@
     template<class Data, class Handler>
     class ConstantConvenientEmbeddedSet {
         public:
-            ConstantConvenientEmbeddedSet() : m_data(0), m_dataSize(0), m_centralFreeItem(-1) {
+            ConstantConvenientEmbeddedSet() : m_data(nullptr), m_dataSize(0), m_centralFreeItem(-1) {
             }
             ConstantConvenientEmbeddedSet(const Data* data, uint count, int centralFreeItem) : m_data(data), m_dataSize(count), m_centralFreeItem(centralFreeItem) {
             }
@@ -151,7 +151,7 @@
     template<class Data, class Handler>
     class ConvenientEmbeddedSetIterator : public ConstantConvenientEmbeddedSet<Data, Handler> {
         public:
-        ConvenientEmbeddedSetIterator(const Data* data = 0, uint count = 0, int centralFreeItem = -1) : ConstantConvenientEmbeddedSet<Data, Handler>(data, count, centralFreeItem), m_pos(0) {
+        ConvenientEmbeddedSetIterator(const Data* data = nullptr, uint count = 0, int centralFreeItem = -1) : ConstantConvenientEmbeddedSet<Data, Handler>(data, count, centralFreeItem), m_pos(0) {
             //Move to first valid position
             moveToValid();
         }
diff --git a/util/embeddedfreetree.h b/util/embeddedfreetree.h
--- a/util/embeddedfreetree.h
+++ b/util/embeddedfreetree.h
@@ -274,7 +274,7 @@
             }
 
             ///Transfers the data into a new item-list. The size of the new item-list must equal newItemCount()
-            void transferData(Data* newItems, uint newCount, int* newCentralFree = 0) {
+            void transferData(Data* newItems, uint newCount, int* newCentralFree = nullptr) {
                 DEBUG_FREEITEM_COUNT
 
                 uint currentRealCount = m_itemCount - countFreeItems(*m_centralFreeItem);
@@ -756,7 +756,7 @@
             }
 
             ///Transfers the data into a new item-list. The size of the new item-list must equal newItemCount()
-            void transferData(Data* newItems, uint newCount, int* newCentralFree = 0) {
+            void transferData(Data* newItems, uint newCount, int* newCentralFree = nullptr) {
                 DEBUG_FREEITEM_COUNT
                 //We only transfer into a new list when all the free items are used up
 
diff --git a/vcs/vcsjob.h b/vcs/vcsjob.h
--- a/vcs/vcsjob.h
+++ b/vcs/vcsjob.h
@@ -44,7 +44,7 @@
 {
     Q_OBJECT
 public:
-    explicit VcsJob( QObject* parent = 0, OutputJobVerbosity verbosity = OutputJob::Verbose);
+    explicit VcsJob( QObject* parent = nullptr, OutputJobVerbosity verbosity = OutputJob::Verbose);
     virtual ~VcsJob();
     /**
      * To easily check which type of job this is.