diff --git a/clock.cpp b/clock.cpp
--- a/clock.cpp
+++ b/clock.cpp
@@ -103,7 +103,7 @@
             {
                 QPointF initPos = (2 * center + target[(i + 2) % 12]->pos()) / 3;
                 addCardForDeal( target[i], c, true, initPos );
-                c = 0;
+                c = nullptr;
                 break;
             }
         }
diff --git a/dealer.h b/dealer.h
--- a/dealer.h
+++ b/dealer.h
@@ -38,7 +38,6 @@
 #ifndef DEALER_H
 #define DEALER_H
 
-class CardDiff;
 class DealerInfo;
 #include "gamestate.h"
 class MessageBox;
@@ -57,7 +56,6 @@
 #include <QMap>
 #include <QStack>
 #include <QTimer>
-class QDomDocument;
 
 
 class DealerScene : public KCardScene
diff --git a/dealer.cpp b/dealer.cpp
--- a/dealer.cpp
+++ b/dealer.cpp
@@ -107,7 +107,7 @@
         }
     }
 
-    int readIntAttribute( const QXmlStreamReader & xml, const QString & key, bool * ok = 0 )
+    int readIntAttribute( const QXmlStreamReader & xml, const QString & key, bool * ok = nullptr )
     {
         QStringRef value = xml.attributes().value( key );
         return QString::fromRawData( value.data(), value.length() ).toInt( ok );
@@ -539,9 +539,9 @@
 
 DealerScene::DealerScene( const DealerInfo * di )
   : m_di( di ),
-    m_solver( 0 ),
-    m_solverThread( 0 ),
-    m_peekedCard( 0 ),
+    m_solver( nullptr ),
+    m_solverThread( nullptr ),
+    m_peekedCard( nullptr ),
     m_dealNumber( 0 ),
     m_loadedMoveCount( 0 ),
     m_neededFutureMoves( 1 ),
@@ -567,7 +567,7 @@
     m_dropQueued( false ),
     m_newCardsQueued( false ),
     m_takeStateQueued( false ),
-    m_currentState( 0 )
+    m_currentState( nullptr )
 {
     setItemIndexMethod(QGraphicsScene::NoIndex);
 
@@ -601,9 +601,9 @@
     if ( m_solverThread )
         m_solverThread->abort();
     delete m_solverThread;
-    m_solverThread = 0;
+    m_solverThread = nullptr;
     delete m_solver;
-    m_solver = 0;
+    m_solver = nullptr;
     qDeleteAll( m_undoStack );
     delete m_currentState;
     qDeleteAll( m_redoStack );
@@ -874,7 +874,7 @@
     qDeleteAll( m_undoStack );
     m_undoStack.clear();
     delete m_currentState;
-    m_currentState = 0;
+    m_currentState = nullptr;
     qDeleteAll( m_redoStack );
     m_redoStack.clear();
     m_lastKnownCardStates.clear();
@@ -1089,7 +1089,7 @@
     {
         e->accept();
         updatePileLayout( m_peekedCard->pile(), DURATION_FANCYSHOW );
-        m_peekedCard = 0;
+        m_peekedCard = nullptr;
     }
     else
     {
@@ -1712,7 +1712,7 @@
     delete m_solver;
     delete m_solverThread;
     m_solver = s;
-    m_solverThread = 0;
+    m_solverThread = nullptr;
 }
 
 bool DealerScene::isGameWon() const
@@ -1892,7 +1892,7 @@
         {
             p.save();
             p.setTransform( item->deviceTransform( p.worldTransform() ), false );
-            item->paint( &p, 0 );
+            item->paint( &p, nullptr );
             p.restore();
         }
     }
@@ -1955,7 +1955,7 @@
            || m_dealWasJustSaved
            || m_toldAboutWonGame
            || m_toldAboutLostGame
-           || KMessageBox::warningContinueCancel(0,
+           || KMessageBox::warningContinueCancel(nullptr,
                      i18n("A new game has been requested, but there is already a game in progress.\n\n"
                           "A loss will be recorded in the statistics if the current game is abandoned."),
                      i18n("Abandon Current Game?"),
diff --git a/dealerinfo.h b/dealerinfo.h
--- a/dealerinfo.h
+++ b/dealerinfo.h
@@ -40,7 +40,6 @@
 
 class DealerInfoList;
 class DealerScene;
-class Solver;
 
 #include <QByteArray>
 #include <QList>
diff --git a/freecell.cpp b/freecell.cpp
--- a/freecell.cpp
+++ b/freecell.cpp
@@ -46,9 +46,6 @@
 #include <KLocalizedString>
 
 
-const int CHUNKSIZE = 100;
-
-
 Freecell::Freecell( const DealerInfo * di )
   : DealerScene( di )
 {
diff --git a/gameselectionscene.cpp b/gameselectionscene.cpp
--- a/gameselectionscene.cpp
+++ b/gameselectionscene.cpp
@@ -146,7 +146,7 @@
         update();
     }
 
-    void paint( QPainter * painter, const QStyleOptionGraphicsItem * option, QWidget * widget = 0 ) Q_DECL_OVERRIDE
+    void paint( QPainter * painter, const QStyleOptionGraphicsItem * option, QWidget * widget = nullptr ) Q_DECL_OVERRIDE
     {
         Q_UNUSED( option )
         Q_UNUSED( widget )
diff --git a/gamestate.h b/gamestate.h
--- a/gamestate.h
+++ b/gamestate.h
@@ -55,7 +55,7 @@
     bool takenDown;
 
     CardState()
-      : pile( 0 ),
+      : pile( nullptr ),
         index( -1 ),
         faceUp( false ),
         takenDown( false )
diff --git a/hint.h b/hint.h
--- a/hint.h
+++ b/hint.h
@@ -47,8 +47,8 @@
 {
 public:
     MoveHint()
-      : m_card( 0 ),
-        m_to( 0 ),
+      : m_card( nullptr ),
+        m_to( nullptr ),
         m_priority( 0 )
     {
     }
diff --git a/idiot.cpp b/idiot.cpp
--- a/idiot.cpp
+++ b/idiot.cpp
@@ -171,7 +171,7 @@
          && card->pile() != talon
          && card->pile() != m_away )
     {
-        KCardPile * destination = 0;
+        KCardPile * destination = nullptr;
         if ( canMoveAway( card ) )
             destination = m_away;
         else if ( m_play[0]->isEmpty() )
diff --git a/klondike.h b/klondike.h
--- a/klondike.h
+++ b/klondike.h
@@ -74,16 +74,14 @@
     void setEasy( bool easy );
 
     bool easyRules;
-    bool redealt;
 
     KSelectAction *options;
 
     PatPile* talon;
     PatPile* play[7];
     PatPile* target[4];
 
     KlondikePile *pile;
-    KCardDeck::Rank target_tops[4];
 
     friend class KlondikeSolver;
 };
diff --git a/klondike.cpp b/klondike.cpp
--- a/klondike.cpp
+++ b/klondike.cpp
@@ -138,7 +138,6 @@
 
     setActions(DealerScene::Hint | DealerScene::Demo | DealerScene::Draw);
     setSolver( new KlondikeSolver( this, pile->cardsToShow() ) );
-    redealt = false;
 
     options = new KSelectAction(i18n("Klondike &Options"), this );
     options->addAction( i18n("Draw 1" ));
@@ -203,7 +202,6 @@
         // Move the cards from the pile back to the deck
         flipCardsToPile( pile->cards(), talon, DURATION_MOVE );
 
-        redealt = true;
     }
     else
     {
@@ -224,7 +222,6 @@
 
 void Klondike::restart( const QList<KCard*> & cards )
 {
-    redealt = false;
 
     QList<KCard*> cardList = cards;
 
diff --git a/libkcardgame/kabstractcarddeck.h b/libkcardgame/kabstractcarddeck.h
--- a/libkcardgame/kabstractcarddeck.h
+++ b/libkcardgame/kabstractcarddeck.h
@@ -26,15 +26,14 @@
 
 #include <QObject>
 class QSize;
-class QPainter;
 
 
 class LIBKCARDGAME_EXPORT KAbstractCardDeck : public QObject
 {
     Q_OBJECT
 
 public:
-    explicit KAbstractCardDeck( const KCardTheme & theme = KCardTheme(), QObject * parent = 0 );
+    explicit KAbstractCardDeck( const KCardTheme & theme = KCardTheme(), QObject * parent = nullptr );
     virtual ~KAbstractCardDeck();
 
     void setDeckContents( const QList<quint32> & ids );
diff --git a/libkcardgame/kabstractcarddeck.cpp b/libkcardgame/kabstractcarddeck.cpp
--- a/libkcardgame/kabstractcarddeck.cpp
+++ b/libkcardgame/kabstractcarddeck.cpp
@@ -37,7 +37,6 @@
 namespace
 {
     const QString cacheNameTemplate( QStringLiteral("libkcardgame-themes/%1") );
-    const QString timeStampKey( QStringLiteral("libkcardgame_timestamp") );
     const QString unscaledSizeKey( QStringLiteral("libkcardgame_unscaledsize") );
     const QString lastUsedSizeKey( QStringLiteral("libkcardgame_lastusedsize") );
 
@@ -100,9 +99,9 @@
   : QObject( q ),
     q( q ),
     animationCheckTimer( new QTimer( this ) ),
-    cache( 0 ),
-    svgRenderer( 0 ),
-    thread( 0 )
+    cache( nullptr ),
+    svgRenderer( nullptr ),
+    thread( nullptr )
 
 {
     animationCheckTimer->setSingleShot( true );
@@ -226,7 +225,7 @@
     if ( thread && thread->isRunning() )
         thread->halt();
     delete thread;
-    thread = 0;
+    thread = nullptr;
 }
 
 
@@ -449,7 +448,7 @@
         {
             QMutexLocker l( &(d->rendererMutex) );
             delete d->svgRenderer;
-            d->svgRenderer = 0;
+            d->svgRenderer = nullptr;
         }
 
         delete d->cache;
diff --git a/libkcardgame/kcard.h b/libkcardgame/kcard.h
--- a/libkcardgame/kcard.h
+++ b/libkcardgame/kcard.h
@@ -39,7 +39,7 @@
     enum { Type = QGraphicsItem::UserType + 1 };
     int type() const Q_DECL_OVERRIDE;
 
-    void paint( QPainter * painter, const QStyleOptionGraphicsItem * option, QWidget * widget = 0 ) Q_DECL_OVERRIDE;
+    void paint( QPainter * painter, const QStyleOptionGraphicsItem * option, QWidget * widget = nullptr ) Q_DECL_OVERRIDE;
 
     quint32 id() const;
     int rank() const;
diff --git a/libkcardgame/kcard.cpp b/libkcardgame/kcard.cpp
--- a/libkcardgame/kcard.cpp
+++ b/libkcardgame/kcard.cpp
@@ -136,9 +136,9 @@
     d->highlighted = false;
     d->highlightValue = d->highlighted ? 1 : 0;
 
-    d->pile = 0;
+    d->pile = nullptr;
 
-    d->animation = 0;
+    d->animation = nullptr;
 
     d->fadeAnimation = new QPropertyAnimation( d, "highlightedness", d );
     d->fadeAnimation->setDuration( 150 );
@@ -249,7 +249,7 @@
 
 bool KCard::isAnimated() const
 {
-    return d->animation != 0;
+    return d->animation != nullptr;
 }
 
 
@@ -301,7 +301,7 @@
         return;
 
     delete d->animation;
-    d->animation = 0;
+    d->animation = nullptr;
 
     setZValue( d->destZ );
 
diff --git a/libkcardgame/kcarddeck.h b/libkcardgame/kcarddeck.h
--- a/libkcardgame/kcarddeck.h
+++ b/libkcardgame/kcarddeck.h
@@ -64,7 +64,7 @@
                                           const QList<Suit> & suits = standardSuits(),
                                           const QList<Rank> & ranks = standardRanks() );
 
-    explicit KCardDeck( const KCardTheme & theme = KCardTheme(), QObject * parent = 0 );
+    explicit KCardDeck( const KCardTheme & theme = KCardTheme(), QObject * parent = nullptr );
     virtual ~KCardDeck();
 
     int rankFromId( quint32 id ) const Q_DECL_OVERRIDE;
diff --git a/libkcardgame/kcardpile.h b/libkcardgame/kcardpile.h
--- a/libkcardgame/kcardpile.h
+++ b/libkcardgame/kcardpile.h
@@ -42,7 +42,6 @@
 class KCardScene;
 #include "libkcardgame_export.h"
 
-class QPropertyAnimation;
 #include <QGraphicsPixmapItem>
 
 
@@ -58,7 +57,7 @@
     int type() const Q_DECL_OVERRIDE;
 
     QRectF boundingRect() const Q_DECL_OVERRIDE;
-    void paint( QPainter * painter, const QStyleOptionGraphicsItem * option, QWidget * widget = 0 ) Q_DECL_OVERRIDE;
+    void paint( QPainter * painter, const QStyleOptionGraphicsItem * option, QWidget * widget = nullptr ) Q_DECL_OVERRIDE;
 
     QList<KCard*> cards() const;
     int count() const;
diff --git a/libkcardgame/kcardpile.cpp b/libkcardgame/kcardpile.cpp
--- a/libkcardgame/kcardpile.cpp
+++ b/libkcardgame/kcardpile.cpp
@@ -141,7 +141,7 @@
 KCardPile::~KCardPile()
 {
     foreach ( KCard * c, d->cards )
-        c->setPile( 0 );
+        c->setPile( nullptr );
 
     KCardScene * cardScene = dynamic_cast<KCardScene*>( scene() );
     if ( cardScene )
@@ -197,15 +197,15 @@
 KCard * KCardPile::at( int index ) const
 {
     if ( index < 0 || index >= d->cards.size() )
-        return 0;
+        return nullptr;
     return d->cards.at( index );
 }
 
 
 KCard * KCardPile::topCard() const
 {
     if ( d->cards.isEmpty() )
-        return 0;
+        return nullptr;
 
     return d->cards.last();
 }
@@ -441,7 +441,7 @@
 {
     Q_ASSERT( d->cards.contains( card ) );
     d->cards.removeAll( card );
-    card->setPile( 0 );
+    card->setPile( nullptr );
 }
 
 
diff --git a/libkcardgame/kcardscene.h b/libkcardgame/kcardscene.h
--- a/libkcardgame/kcardscene.h
+++ b/libkcardgame/kcardscene.h
@@ -41,7 +41,7 @@
 
 class KCard;
 class KAbstractCardDeck;
-class HighlightableItem;
+
 #include "libkcardgame_export.h"
 class KCardPile;
 
@@ -66,7 +66,7 @@
     };
     Q_DECLARE_FLAGS(SceneAlignment, SceneAlignmentFlag)
 
-    explicit KCardScene( QObject * parent = 0 );
+    explicit KCardScene( QObject * parent = nullptr );
     ~KCardScene();
 
     void setDeck( KAbstractCardDeck * deck );
diff --git a/libkcardgame/kcardscene.cpp b/libkcardgame/kcardscene.cpp
--- a/libkcardgame/kcardscene.cpp
+++ b/libkcardgame/kcardscene.cpp
@@ -82,9 +82,9 @@
         if ( KCardPile * pile = qobject_cast<KCardPile*>( object ) )
             return pile;
 
-        Q_ASSERT( object == 0 );
+        Q_ASSERT( !object );
 
-        return 0;
+        return nullptr;
     }
 }
 
@@ -148,7 +148,7 @@
             targets << p;
     }
 
-    KCardPile * bestTarget = 0;
+    KCardPile * bestTarget = nullptr;
     qreal bestArea = 1;
 
     foreach ( KCardPile * p, targets )
@@ -409,7 +409,7 @@
   : QGraphicsScene( parent ),
     d( new KCardScenePrivate( this ) )
 {
-    d->deck = 0;
+    d->deck = nullptr;
     d->alignment = AlignHCenter | AlignHSpread;
     d->layoutMargin = 0.15;
     d->layoutSpacing = 0.15;
@@ -1177,12 +1177,12 @@
         if ( e->button() == Qt::LeftButton )
         {
             emit pileClicked( pile );
-            emit pile->clicked( 0 );
+            emit pile->clicked( nullptr );
         }
         else if ( e->button() == Qt::RightButton )
         {
             emit pileRightClicked( pile );
-            emit pile->rightClicked( 0 );
+            emit pile->rightClicked( nullptr );
         }
     }
     else
@@ -1216,7 +1216,7 @@
     {
         e->accept();
         emit pileDoubleClicked( pile );
-        emit pile->doubleClicked( 0 );
+        emit pile->doubleClicked( nullptr );
     }
     else
     {
diff --git a/libkcardgame/kcardtheme.cpp b/libkcardgame/kcardtheme.cpp
--- a/libkcardgame/kcardtheme.cpp
+++ b/libkcardgame/kcardtheme.cpp
@@ -102,7 +102,7 @@
 
 
 KCardTheme::KCardTheme()
-  : d( 0 )
+  : d( nullptr )
 {
 }
 
diff --git a/libkcardgame/kcardthemewidget.h b/libkcardgame/kcardthemewidget.h
--- a/libkcardgame/kcardthemewidget.h
+++ b/libkcardgame/kcardthemewidget.h
@@ -29,7 +29,7 @@
 class LIBKCARDGAME_EXPORT KCardThemeWidget : public QWidget
 {
 public:
-    explicit KCardThemeWidget( const QSet<QString> & requiredFeatures, const QString & previewString, QWidget * parent = 0 );
+    explicit KCardThemeWidget( const QSet<QString> & requiredFeatures, const QString & previewString, QWidget * parent = nullptr );
     virtual ~KCardThemeWidget();
 
     void setCurrentSelection( const QString & dirName );
diff --git a/libkcardgame/kcardthemewidget.cpp b/libkcardgame/kcardthemewidget.cpp
--- a/libkcardgame/kcardthemewidget.cpp
+++ b/libkcardgame/kcardthemewidget.cpp
@@ -115,7 +115,7 @@
 CardThemeModel::CardThemeModel( KCardThemeWidgetPrivate * d, QObject * parent )
   : QAbstractListModel( parent ),
     d( d ),
-    m_thread( 0 )
+    m_thread( nullptr )
 {
     qRegisterMetaType<KCardTheme>();
 
@@ -190,7 +190,7 @@
     if ( m_thread && m_thread->isRunning() )
         m_thread->halt();
     delete m_thread;
-    m_thread = 0;
+    m_thread = nullptr;
 }
 
 
diff --git a/libkcardgame/kcardthemewidget_p.h b/libkcardgame/kcardthemewidget_p.h
--- a/libkcardgame/kcardthemewidget_p.h
+++ b/libkcardgame/kcardthemewidget_p.h
@@ -61,7 +61,7 @@
     Q_OBJECT
 
 public:
-    explicit CardThemeModel( KCardThemeWidgetPrivate * d, QObject * parent = 0 );
+    explicit CardThemeModel( KCardThemeWidgetPrivate * d, QObject * parent = nullptr );
     virtual ~CardThemeModel();
 
     void reload();
@@ -85,7 +85,7 @@
 class CardThemeDelegate : public QAbstractItemDelegate
 {
 public:
-    explicit CardThemeDelegate( KCardThemeWidgetPrivate * d, QObject * parent = 0 );
+    explicit CardThemeDelegate( KCardThemeWidgetPrivate * d, QObject * parent = nullptr );
 
     void paint( QPainter * painter, const QStyleOptionViewItem & option, const QModelIndex & index ) const Q_DECL_OVERRIDE;
     QSize sizeHint( const QStyleOptionViewItem & option, const QModelIndex & index ) const Q_DECL_OVERRIDE;
diff --git a/main.cpp b/main.cpp
--- a/main.cpp
+++ b/main.cpp
@@ -77,13 +77,13 @@
             if ( !d->solver() )
             {
                 qCritical() << "There is no solver for" << di->nameForId( wanted_game );;
-                return 0;
+                return nullptr;
             }
 
             return d;
         }
     }
-    return 0;
+    return nullptr;
 }
 
 // A function to remove all nonalphanumeric characters from a string
diff --git a/mainwindow.cpp b/mainwindow.cpp
--- a/mainwindow.cpp
+++ b/mainwindow.cpp
@@ -95,13 +95,13 @@
 
 
 MainWindow::MainWindow()
-  : KXmlGuiWindow( 0 ),
-    m_view( 0 ),
-    m_dealer( 0 ),
-    m_selector( 0 ),
-    m_cardDeck( 0 ),
-    m_soundEngine( 0 ),
-    m_dealDialog( 0 )
+  : KXmlGuiWindow( nullptr ),
+    m_view( nullptr ),
+    m_dealer( nullptr ),
+    m_selector( nullptr ),
+    m_cardDeck( nullptr ),
+    m_soundEngine( nullptr ),
+    m_dealDialog( nullptr )
 {
     setObjectName( QStringLiteral( "MainWindow" ) );
     // KCrash::setEmergencySaveFunction(::saveGame);
@@ -215,7 +215,7 @@
     // action, so we must create a new action and copy all the standard
     // properties over one by one.
     m_hintAction = new KToggleAction( actionCollection() );
-    a = KStandardGameAction::hint( 0, 0, 0 );
+    a = KStandardGameAction::hint( nullptr, nullptr, nullptr );
     m_hintAction->setText( a->text() );
     m_hintAction->setIcon( a->icon() );
     actionCollection()->setDefaultShortcut( m_hintAction, a->shortcut() );
@@ -506,8 +506,8 @@
     {
         m_dealer->recordGameStatistics();
         delete m_dealer;
-        m_view->setScene(0);
-        m_dealer = 0;
+        m_view->setScene(nullptr);
+        m_dealer = nullptr;
     }
 
     if ( !m_cardDeck )
@@ -553,8 +553,8 @@
         {
             m_dealer->recordGameStatistics();
             delete m_dealer;
-            m_view->setScene(0);
-            m_dealer = 0;
+            m_view->setScene(nullptr);
+            m_dealer = nullptr;
         }
 
         if (!m_selector)
@@ -684,7 +684,7 @@
         }
         else if ( m_soundEngine )
         {
-            disconnect( m_dealer, 0, m_soundEngine, 0 );
+            disconnect( m_dealer, nullptr, m_soundEngine, nullptr );
         }
     }
 }
diff --git a/patsolve/clocksolver.cpp b/patsolve/clocksolver.cpp
--- a/patsolve/clocksolver.cpp
+++ b/patsolve/clocksolver.cpp
@@ -115,8 +115,6 @@
 
 int ClockSolver::get_possible_moves(int *a, int *numout)
 {
-    int w, o;
-    card_t card;
     MOVE *mp;
 
     /* Check for moves from W to O. */
@@ -126,14 +124,14 @@
     int left_in_play = 0;
     int n = 0;
     mp = Possible;
-    for (w = 0; w < 8; ++w)
+    for (int w = 0; w < 8; ++w)
     {
         left_in_play += Wlen[w];
 
         if (Wlen[w] > 0)
         {
-            card = *Wp[w];
-            o = SUIT(card);
+            card_t card = *Wp[w];
+            auto o = SUIT(card);
             for ( int i = 0; i < 12; ++i )
             {
                 if ( o != SUIT( W[8][i] ) )
@@ -155,8 +153,6 @@
                 mp->turn_index = -1;
                 n++;
                 mp++;
-                //*a = true;
-                //return n;
             }
         } else if ( first_empty < 0 )
             first_empty = w;
@@ -184,14 +180,14 @@
             if ( Wlen[j] == 0 )
             {
                 if ( Wlen[i] > 1 && first_empty == j )
-                    allowed = 1;
+                    allowed = true;
             } else
             {
                 card_t below = *Wp[j];
 
                 if ( RANK(card) == RANK( below ) - 1 )
                 {
-                    allowed = 1;
+                    allowed = true;
                 }
             }
 
diff --git a/patsolve/fortyeightsolver.h b/patsolve/fortyeightsolver.h
--- a/patsolve/fortyeightsolver.h
+++ b/patsolve/fortyeightsolver.h
@@ -27,7 +27,6 @@
 {
 public:
     explicit FortyeightSolver(const Fortyeight *dealer);
-    int good_automove(int o, int r);
     int get_possible_moves(int *a, int *numout) Q_DECL_OVERRIDE;
     bool isWon() Q_DECL_OVERRIDE;
     void make_move(MOVE *m) Q_DECL_OVERRIDE;
diff --git a/patsolve/fortyeightsolver.cpp b/patsolve/fortyeightsolver.cpp
--- a/patsolve/fortyeightsolver.cpp
+++ b/patsolve/fortyeightsolver.cpp
@@ -626,7 +626,7 @@
 {
     if ( m.from == NUM_DECK || m.to == NUM_DECK )
         return MoveHint();
-    PatPile *frompile = 0;
+    PatPile *frompile = nullptr;
     if ( m.from < 8 )
         frompile = deal->stack[m.from];
     else
diff --git a/patsolve/freecellsolver.cpp b/patsolve/freecellsolver.cpp
--- a/patsolve/freecellsolver.cpp
+++ b/patsolve/freecellsolver.cpp
@@ -450,17 +450,17 @@
 {
     // this is tricky as we need to want to build the "meta moves"
 
-    PatPile *frompile = 0;
+    PatPile *frompile = nullptr;
     if ( m.from < 8 )
         frompile = deal->store[m.from];
     else
         frompile = deal->freecell[m.from-8];
     KCard *card = frompile->at( frompile->count() - m.card_index - 1);
 
     if ( m.totype == O_Type )
     {
-        PatPile *target = 0;
-        PatPile *empty = 0;
+        PatPile *target = nullptr;
+        PatPile *empty = nullptr;
         for (int i = 0; i < 4; ++i) {
             KCard *c = deal->target[i]->topCard();
             if (c) {
@@ -476,7 +476,7 @@
             target = empty;
         return MoveHint( card, target, m.pri );
     } else {
-        PatPile *target = 0;
+        PatPile *target = nullptr;
         if ( m.to < 8 )
             target = deal->store[m.to];
         else
diff --git a/patsolve/golfsolver.h b/patsolve/golfsolver.h
--- a/patsolve/golfsolver.h
+++ b/patsolve/golfsolver.h
@@ -26,7 +26,7 @@
 {
 public:
     explicit GolfSolver(const Golf *dealer);
-    int good_automove(int o, int r);
+
     int get_possible_moves(int *a, int *numout) Q_DECL_OVERRIDE;
     bool isWon() Q_DECL_OVERRIDE;
     void make_move(MOVE *m) Q_DECL_OVERRIDE;
diff --git a/patsolve/grandfsolver.h b/patsolve/grandfsolver.h
--- a/patsolve/grandfsolver.h
+++ b/patsolve/grandfsolver.h
@@ -26,7 +26,7 @@
 {
 public:
     explicit GrandfSolver(const Grandf *dealer);
-    int good_automove(int o, int r);
+
     int get_possible_moves(int *a, int *numout) Q_DECL_OVERRIDE;
     bool isWon() Q_DECL_OVERRIDE;
     void make_move(MOVE *m) Q_DECL_OVERRIDE;
diff --git a/patsolve/grandfsolver.cpp b/patsolve/grandfsolver.cpp
--- a/patsolve/grandfsolver.cpp
+++ b/patsolve/grandfsolver.cpp
@@ -40,11 +40,10 @@
     //print_layout();
 #endif
 
-    int from, to;
     card_t card = NONE;
 
-    from = m->from;
-    to = m->to;
+    auto from = m->from;
+    auto to = m->to;
 
     if ( from == offs )
     {
@@ -456,15 +455,15 @@
     if ( m.from == offs )
         return MoveHint();
 
-    PatPile *frompile = 0;
+    PatPile *frompile = nullptr;
     frompile = deal->store[m.from % 7];
 
     KCard *card = frompile->at( frompile->count() - m.card_index - 1);
 
     if ( m.totype == O_Type )
     {
-        PatPile *target = 0;
-        PatPile *empty = 0;
+        PatPile *target = nullptr;
+        PatPile *empty = nullptr;
         for (int i = 0; i < 4; ++i) {
             KCard *c = deal->target[i]->topCard();
             if (c) {
@@ -482,7 +481,6 @@
     } else {
         return MoveHint( card, deal->store[m.to % 7], m.pri );
     }
-    return MoveHint();
 }
 
 void GrandfSolver::print_layout()
diff --git a/patsolve/gypsysolver.cpp b/patsolve/gypsysolver.cpp
--- a/patsolve/gypsysolver.cpp
+++ b/patsolve/gypsysolver.cpp
@@ -538,8 +538,8 @@
 
     if ( m.totype == O_Type )
     {
-        PatPile *target = 0;
-        PatPile *empty = 0;
+        PatPile *target = nullptr;
+        PatPile *empty = nullptr;
         for (int i = 0; i < 8; ++i) {
             KCard *c = deal->target[i]->topCard();
             if (c) {
diff --git a/patsolve/idiotsolver.cpp b/patsolve/idiotsolver.cpp
--- a/patsolve/idiotsolver.cpp
+++ b/patsolve/idiotsolver.cpp
@@ -242,7 +242,7 @@
     KCard *card = frompile->at( frompile->count() - m.card_index - 1);
     Q_ASSERT( card );
 
-    PatPile *target = 0;
+    PatPile *target = nullptr;
     if ( m.to == 5 )
         target = deal->m_away;
     else
diff --git a/patsolve/klondikesolver.cpp b/patsolve/klondikesolver.cpp
--- a/patsolve/klondikesolver.cpp
+++ b/patsolve/klondikesolver.cpp
@@ -538,7 +538,7 @@
 
 MoveHint KlondikeSolver::translateMove( const MOVE &m )
 {
-    PatPile *frompile = 0;
+    PatPile *frompile = nullptr;
     if ( m.from == 8 && m.to == 7 )
         return MoveHint();
     Q_ASSERT( m.from != 8 );
@@ -551,8 +551,8 @@
 
     if ( m.totype == O_Type )
     {
-        PatPile *target = 0;
-        PatPile *empty = 0;
+        PatPile *target = nullptr;
+        PatPile *empty = nullptr;
         for (int i = 0; i < 4; ++i) {
             KCard *c = deal->target[i]->topCard();
             if (c) {
diff --git a/patsolve/memory.h b/patsolve/memory.h
--- a/patsolve/memory.h
+++ b/patsolve/memory.h
@@ -68,7 +68,7 @@
     TREELIST *cluster_tree(unsigned int cluster);
     inscode insert_node(TREE *n, int d, TREE **tree, TREE **node);
     void give_back_block(unsigned char *p);
-    void init_buckets( int i );
+
     BLOCK *new_block(void);
 
     template<class T>
diff --git a/patsolve/memory.cpp b/patsolve/memory.cpp
--- a/patsolve/memory.cpp
+++ b/patsolve/memory.cpp
@@ -42,27 +42,27 @@
 
 	key = (quint8 *)n + sizeof(TREE);
 	n->depth = d;
-	n->left = n->right = NULL;
+	n->left = n->right = nullptr;
 	*node = n;
 	t = *tree;
-	if (t == NULL) {
+	if (t == nullptr) {
 		*tree = n;
 		return NEW;
 	}
-	while (1) {
+	while (true) {
 		tkey = (quint8 *)t + sizeof(TREE);
 		c = memcmp(key, tkey, Pilebytes);
 		if (c == 0) {
 			break;
 		}
 		if (c < 0) {
-			if (t->left == NULL) {
+			if (t->left == nullptr) {
 				t->left = n;
 				return NEW;
 			}
 			t = t->left;
 		} else {
-			if (t->right == NULL) {
+			if (t->right == nullptr) {
 				t->right = n;
 				return NEW;
 			}
@@ -104,7 +104,7 @@
 
 	/* Find the tree in this bucket with that cluster number. */
 
-	last = NULL;
+	last = nullptr;
 	for (tl = Treelist[bucket]; tl; tl = tl->next) {
 		if (tl->cluster == cluster) {
 			break;
@@ -114,15 +114,15 @@
 
 	/* If we didn't find it, make a new one and add it to the list. */
 
-	if (tl == NULL) {
+	if (tl == nullptr) {
 		tl = mm_allocate(TREELIST);
-		if (tl == NULL) {
-			return NULL;
+		if (tl == nullptr) {
+			return nullptr;
 		}
-		tl->tree = NULL;
+		tl->tree = nullptr;
 		tl->cluster = cluster;
-		tl->next = NULL;
-		if (last == NULL) {
+		tl->next = nullptr;
+		if (last == nullptr) {
 			Treelist[bucket] = tl;
 		} else {
 			last->next = tl;
@@ -139,17 +139,17 @@
 	BLOCK *b;
 
 	b = mm_allocate(BLOCK);
-	if (b == NULL) {
-		return NULL;
+	if (b == nullptr) {
+		return nullptr;
 	}
 	b->block = new_array(quint8, BLOCKSIZE);
-	if (b->block == NULL) {
+	if (b->block == nullptr) {
                 MemoryManager::free_ptr(b);
-		return NULL;
+		return nullptr;
 	}
 	b->ptr = b->block;
 	b->remain = BLOCKSIZE;
-	b->next = NULL;
+	b->next = nullptr;
 
 	return b;
 }
@@ -164,8 +164,8 @@
 	b = Block;
 	if (s > b->remain) {
 		b = new_block();
-		if (b == NULL) {
-			return NULL;
+		if (b == nullptr) {
+			return nullptr;
 		}
 		b->next = Block;
 		Block = b;
@@ -228,14 +228,14 @@
 	void *x;
 
 	if (s > Mem_remain) {
-		return NULL;
+		return nullptr;
 	}
 
-	if ((x = (void *)malloc(s)) == NULL) {
-		return NULL;
+	// use calloc to ensure that the memory is zeroed
+	if ((x = calloc(1, s)) == nullptr) {
+		return nullptr;
 	}
 
-        memset( x, 0, s );
 	Mem_remain -= s;
 	return x;
 }
diff --git a/patsolve/patsolve.h b/patsolve/patsolve.h
--- a/patsolve/patsolve.h
+++ b/patsolve/patsolve.h
@@ -53,16 +53,13 @@
     }
 };
 
-struct POSITION;
-
 struct POSITION {
         POSITION *queue;      /* next position in the queue */
 	POSITION *parent;     /* point back up the move stack */
 	TREE *node;             /* compact position rep.'s tree node */
 	MOVE move;              /* move that got us here from the parent */
 	quint32 cluster; /* the cluster this node is in */
 	short depth;            /* number of moves so far */
-	quint8 ntemp;           /* number of cards in T */
 	quint8 nchild;          /* number of child nodes left */
 };
 
@@ -83,7 +80,7 @@
     Solver();
     virtual ~Solver();
     ExitStatus patsolve( int max_positions = -1, bool debug = false);
-    bool recursive(POSITION *pos = 0);
+    bool recursive(POSITION *pos = nullptr);
     virtual void translate_layout() = 0;
     bool m_shouldEnd;
     QMutex endMutex;
@@ -99,8 +96,7 @@
     virtual int get_possible_moves(int *a, int *numout) = 0;
     int translateSuit( int s );
 
-    int wcmp(int a, int b);
-    void queue_position(POSITION *pos, int pri);
+	void queue_position(POSITION *pos, int pri);
     void free_position(POSITION *pos, int);
     POSITION *dequeue_position();
     void hashpile(int w);
@@ -156,7 +152,6 @@
     POSITION *Qhead[NQUEUES]; /* separate queue for each priority */
     int Maxq;
 
-    bool m_newer_piles_first;
     unsigned long Total_generated, Total_positions;
     qreal depth_sum;
 
diff --git a/patsolve/patsolve.cpp b/patsolve/patsolve.cpp
--- a/patsolve/patsolve.cpp
+++ b/patsolve/patsolve.cpp
@@ -95,7 +95,7 @@
 {
     int i, alln, a, numout = 0;
 
-    if ( parent == NULL ) {
+    if ( parent == nullptr ) {
         init();
         recu_pos.clear();
         delete Stack;
@@ -135,7 +135,7 @@
         return false;
 
     MOVE *mp0 = new_array(MOVE, alln+1);
-    if (mp0 == NULL) {
+    if (mp0 == nullptr) {
         return false;
     }
     MOVE *mp = mp0;
@@ -152,7 +152,7 @@
     for (mp = mp0; mp->card_index != -1; ++mp) {
 
         int depth = 0;
-        if (parent != NULL)
+        if (parent != nullptr)
             depth = parent->depth + 1;
 
         make_move(mp);
@@ -164,7 +164,7 @@
 
         Total_generated++;
         POSITION *pos = &Stack[depth];
-        pos->queue = NULL;
+        pos->queue = nullptr;
         pos->parent = parent;
         pos->node = pack_position();
         quint8 *key = (quint8 *)pos->node + sizeof(TREE);
@@ -183,7 +183,7 @@
             quint8 *tkey = (quint8 *)Stack[i].node + sizeof(TREE);
             if ( !memcmp( key, tkey, mm->Pilebytes ) )
             {
-                key = 0;
+                key = nullptr;
                 break;
             }
         }
@@ -214,10 +214,10 @@
 
     MemoryManager::free_array(mp0, alln);
 
-    if ( parent == NULL ) {
+    if ( parent == nullptr ) {
         printf( "Total %ld\n", Total_generated );
         delete [] Stack;
-        Stack = 0;
+        Stack = nullptr;
     }
     return fit;
 }
@@ -254,7 +254,7 @@
 	if (n == 0) {
             /* No more moves - won or lost */
             //print_layout();
-            return NULL;
+            return nullptr;
 	}
 
 	/* Prioritize these moves.  Automoves don't get queued, so they
@@ -271,8 +271,8 @@
 	moves. */
 
 	mp = mp0 = new_array(MOVE, n);
-	if (mp == NULL) {
-		return NULL;
+	if (mp == nullptr) {
+		return nullptr;
 	}
 	*nmoves = n;
 	i = 0;
@@ -306,17 +306,6 @@
 
 int Posbytes;
 
-/* Comparison function for sorting the W piles. */
-
-int Solver::wcmp(int a, int b)
-{
-	if (m_newer_piles_first) {
-		return Wpilenum[b] - Wpilenum[a];       /* newer piles first */
-	} else {
-		return Wpilenum[a] - Wpilenum[b];       /* older piles first */
-	}
-}
-
 void Solver::pilesort(void)
 {
     	/* Make sure all the piles have id numbers. */
@@ -370,9 +359,9 @@
 	will get filled in later, by insert_node(). */
 
 	p = mm->new_from_block(Treebytes);
-	if (p == NULL) {
+	if (p == nullptr) {
                 Status = UnableToDetermineSolvability;
-		return NULL;
+		return nullptr;
 	}
 	node = (TREE *)p;
 	p += sizeof(TREE);
@@ -391,7 +380,7 @@
                 if ( j < 0 )
                 {
                     mm->give_back_block( p );
-                    return NULL;
+                    return nullptr;
                 }
                 *p2++ = j;
 	}
@@ -419,7 +408,6 @@
 void Solver::unpack_position(POSITION *pos)
 {
 	int i, w;
-	quint8 c;
 	BUCKETLIST *l;
 
         unpack_cluster(pos->cluster);
@@ -432,7 +420,7 @@
 		       j             j
 	*/
 
-	w = i = c = 0;
+	w = i = 0;
 	quint16 *p2 = ( quint16* )( (quint8 *)(pos->node) + sizeof(TREE) );
 	while (w < m_number_piles) {
                 i = *p2++;
@@ -481,7 +469,7 @@
     //printf("Winning in %d moves.\n", nmoves);
 
     mpp0 = new_array(MOVE *, nmoves);
-    if (mpp0 == NULL) {
+    if (mpp0 == nullptr) {
         Status = UnableToDetermineSolvability;
         return; /* how sad, so close... */
     }
@@ -551,7 +539,7 @@
 
 	/* Look for the pile in this bucket. */
 
-	last = NULL;
+	last = nullptr;
 	for (l = Bucketlist[bucket]; l; l = l->next) {
 		if (l->hash == Whash[w] &&
 		    strncmp((char*)l->pile, (char*)W[w], Wlen[w]) == 0) {
@@ -562,20 +550,20 @@
 
 	/* If we didn't find it, make a new one and add it to the list. */
 
-	if (l == NULL) {
+	if (l == nullptr) {
 		if (Pilenum >= NPILES ) {
                         Status = UnableToDetermineSolvability;
 			//qDebug() << "out of piles";
 			return -1;
 		}
 		l = mm_allocate(BUCKETLIST);
-		if (l == NULL) {
+		if (l == nullptr) {
                         Status = UnableToDetermineSolvability;
 			//qDebug() << "out of buckets";
 			return -1;
 		}
 		l->pile = new_array(quint8, Wlen[w] + 1);
-		if (l->pile == NULL) {
+		if (l->pile == nullptr) {
                     Status = UnableToDetermineSolvability;
                     MemoryManager::free_ptr(l);
 		    //qDebug() << "out of memory";
@@ -588,8 +576,8 @@
 		strncpy((char*)l->pile, (char*)W[w], Wlen[w] + 1);
 		l->hash = Whash[w];
 		l->pilenum = pilenum = Pilenum++;
-		l->next = NULL;
-		if (last == NULL) {
+		l->next = nullptr;
+		if (last == nullptr) {
 			Bucketlist[bucket] = l;
 		} else {
 			last->next = l;
@@ -642,7 +630,7 @@
 	/* Init the queues. */
 
 	for (i = 0; i < NQUEUES; ++i) {
-		Qhead[i] = NULL;
+		Qhead[i] = nullptr;
 	}
 	Maxq = 0;
 
@@ -652,17 +640,17 @@
 	pilesort();
 	m.card_index = -1;
         m.turn_index = -1;
-	pos = new_position(NULL, &m);
-	if ( pos == NULL )
+	pos = new_position(nullptr, &m);
+	if ( pos == nullptr )
         {
             Status = UnableToDetermineSolvability;
             return;
         }
 	queue_position(pos, 0);
 
 	/* Solve it. */
 
-        while ((pos = dequeue_position()) != NULL) {
+        while ((pos = dequeue_position()) != nullptr) {
 		q = solve(pos);
 		if (!q) {
                     free_position(pos, true);
@@ -709,7 +697,7 @@
 
 	/* Generate an array of all the moves we can make. */
 
-	if ((mp0 = get_moves(&nmoves)) == NULL) {
+	if ((mp0 = get_moves(&nmoves)) == nullptr) {
             if ( isWon() ) {
                 Status = SolutionExists;
                 win( parent );
@@ -738,7 +726,7 @@
 
 		/* See if this is a new position. */
 
-		if ((pos = new_position(parent, mp)) == NULL) {
+		if ((pos = new_position(parent, mp)) == nullptr) {
 			undo_move(mp);
 			parent->nchild--;
 			continue;
@@ -790,7 +778,7 @@
             pos->queue = Freepos;
             Freepos = pos;
             pos = pos->parent;
-            if (pos == NULL) {
+            if (pos == nullptr) {
                 return;
             }
             pos->nchild--;
@@ -827,8 +815,8 @@
 	at the head or tail of the queue, depending on whether we're
 	pretending it's a stack or a queue. */
 
-	pos->queue = NULL;
-	if (Qhead[pri] == NULL) {
+	pos->queue = nullptr;
+	if (Qhead[pri] == nullptr) {
 		Qhead[pri] = pos;
 	} else {
             pos->queue = Qhead[pri];
@@ -857,7 +845,7 @@
 		qpos--;
 		if (qpos < minpos) {
 			if (last) {
-				return NULL;
+				return nullptr;
 			}
 			qpos = Maxq;
 			minpos--;
@@ -868,14 +856,14 @@
 				last = true;
 			}
 		}
-	} while (Qhead[qpos] == NULL);
+	} while (Qhead[qpos] == nullptr);
 
 	pos = Qhead[qpos];
 	Qhead[qpos] = pos->queue;
 
 	/* Decrease Maxq if that queue emptied. */
 
-	while (Qhead[qpos] == NULL && qpos == Maxq && Maxq > 0) {
+	while (Qhead[qpos] == nullptr && qpos == Maxq && Maxq > 0) {
 		Maxq--;
 		qpos--;
 		if (qpos < minpos) {
@@ -893,17 +881,16 @@
 Solver::Solver()
 {
     mm = new MemoryManager();
-    Freepos = NULL;
-    m_newer_piles_first = true;
+    Freepos = nullptr;
     /* Work arrays. */
-    W = 0;
-    Wp = 0;
+    W = nullptr;
+    Wp = nullptr;
 
-    Wlen = 0;
+    Wlen = nullptr;
 
-    Whash = 0;
-    Wpilenum = 0;
-    Stack = 0;
+    Whash = nullptr;
+    Wpilenum = nullptr;
+    Stack = nullptr;
 }
 
 Solver::~Solver()
@@ -944,7 +931,7 @@
     free_buckets();
     mm->free_clusters();
     mm->free_blocks();
-    Freepos = NULL;
+    Freepos = nullptr;
 }
 
 
@@ -1036,14 +1023,14 @@
         /* Get the tree for this cluster. */
 
 	TREELIST *tl = mm->cluster_tree(k);
-	if (tl == NULL) {
+	if (tl == nullptr) {
 		return MemoryManager::ERR;
 	}
 
 	/* Create a compact position representation. */
 
 	TREE *newtree = pack_position();
-	if (newtree == NULL) {
+	if (newtree == nullptr) {
 		return MemoryManager::ERR;
 	}
         Total_generated++;
@@ -1068,7 +1055,7 @@
 	/* Search the list of stored positions.  If this position is found,
 	then ignore it and return (unless this position is better). */
 
-	if (parent == NULL) {
+	if (parent == nullptr) {
 		depth = 0;
 	} else {
 		depth = parent->depth + 1;
@@ -1078,7 +1065,7 @@
                 Total_positions++;
                 depth_sum += depth;
         } else
-            return NULL;
+            return nullptr;
 
 
 	/* A new or better position.  insert() already stashed it in the
@@ -1090,14 +1077,14 @@
 		Freepos = Freepos->queue;
 	} else {
 		p = mm->new_from_block(Posbytes);
-		if (p == NULL) {
+		if (p == nullptr) {
                         Status = UnableToDetermineSolvability;
-			return NULL;
+			return nullptr;
 		}
 	}
 
 	pos = (POSITION *)p;
-	pos->queue = NULL;
+	pos->queue = nullptr;
 	pos->parent = parent;
 	pos->node = node;
 	pos->move = *m;                 /* struct copy */
diff --git a/patsolve/spidersolver.cpp b/patsolve/spidersolver.cpp
--- a/patsolve/spidersolver.cpp
+++ b/patsolve/spidersolver.cpp
@@ -385,14 +385,13 @@
                         else {
                             if ( conti[j]+l+1 != 13 || conti[i]>conti[j]+l )
                             {
-                                card_t card_below;
+                                card_t card_below {};
                                 bool exists_card_below = Wlen[i] >= l + 2;
                                 if (exists_card_below) {
                                     card_below = W[i][Wlen[i]-l-2];
                                 }
-                                if ( !exists_card_below || ( exists_card_below &&
-                                                             (  SUIT( card_below ) != SUIT( card ) ||
-                                                                RANK(card_below) != RANK(card) + 1 )
+                                if ( !exists_card_below || ((SUIT(card_below ) != SUIT(card ) ||
+                                                             RANK(card_below) != RANK(card) + 1)
                                                             )
                                     )
                                 {
@@ -611,7 +610,6 @@
     if ( m.totype == O_Type )
     {
         return MoveHint(); // the move to the legs is fully automated
-        return MoveHint( frompile->topCard(), deal->legs[0], m.pri ); // for now
     }
 
     Q_ASSERT( m.from < 10 && m.to < 10 );
diff --git a/patsolve/yukonsolver.cpp b/patsolve/yukonsolver.cpp
--- a/patsolve/yukonsolver.cpp
+++ b/patsolve/yukonsolver.cpp
@@ -392,15 +392,15 @@
 
 MoveHint YukonSolver::translateMove( const MOVE &m )
 {
-    PatPile *frompile = 0;
+    PatPile *frompile = nullptr;
     frompile = deal->store[m.from];
 
     KCard *card = frompile->at( frompile->count() - m.card_index - 1);
 
     if ( m.totype == O_Type )
     {
-        PatPile *target = 0;
-        PatPile *empty = 0;
+        PatPile *target = nullptr;
+        PatPile *empty = nullptr;
         for (int i = 0; i < 4; ++i) {
             KCard *c = deal->target[i]->topCard();
             if (c) {
diff --git a/renderer.h b/renderer.h
--- a/renderer.h
+++ b/renderer.h
@@ -21,10 +21,8 @@
 
 #include <KGameRenderer>
 
-class QSize;
 class QString;
 class QColor;
-class QPixmap;
 
 
 class Renderer : public KGameRenderer
diff --git a/renderer.cpp b/renderer.cpp
--- a/renderer.cpp
+++ b/renderer.cpp
@@ -23,21 +23,21 @@
 #include <KgThemeProvider>
 
 
-Renderer * Renderer::s_instance = 0;
+Renderer * Renderer::s_instance = nullptr;
 
 
 Renderer * Renderer::self()
 {
-    if ( s_instance == 0 )
+    if ( s_instance == nullptr )
         s_instance = new Renderer();
     return s_instance;
 }
 
 
 void Renderer::deleteSelf()
 {
     delete s_instance;
-    s_instance = 0;
+    s_instance = nullptr;
 }
 
 
diff --git a/soundengine.h b/soundengine.h
--- a/soundengine.h
+++ b/soundengine.h
@@ -26,7 +26,7 @@
     Q_OBJECT
 
 public:
-    explicit SoundEngine( QObject * parent = 0 );
+    explicit SoundEngine( QObject * parent = nullptr );
     virtual ~SoundEngine();
 
 public slots: