diff --git a/src/plugins/coreplugin/dialogs/readonlyfilesdialog.cpp b/src/plugins/coreplugin/dialogs/readonlyfilesdialog.cpp
index b7c58544c96..8f252c07fab 100644
--- a/src/plugins/coreplugin/dialogs/readonlyfilesdialog.cpp
+++ b/src/plugins/coreplugin/dialogs/readonlyfilesdialog.cpp
@@ -140,7 +140,7 @@ ReadOnlyFilesDialog::ReadOnlyFilesDialog(IDocument *document, QWidget *parent,
     initDialog(QStringList() << document->filePath());
 }
 
-ReadOnlyFilesDialog::ReadOnlyFilesDialog(const QList<IDocument *> documents, QWidget *parent)
+ReadOnlyFilesDialog::ReadOnlyFilesDialog(const QList<IDocument *> &documents, QWidget *parent)
     : QDialog(parent)
     , d(new ReadOnlyFilesDialogPrivate)
     , ui(new Ui::ReadOnlyFilesDialog)
diff --git a/src/plugins/coreplugin/dialogs/readonlyfilesdialog.h b/src/plugins/coreplugin/dialogs/readonlyfilesdialog.h
index c99853ae049..a6295b94cbe 100644
--- a/src/plugins/coreplugin/dialogs/readonlyfilesdialog.h
+++ b/src/plugins/coreplugin/dialogs/readonlyfilesdialog.h
@@ -78,7 +78,7 @@ public:
     explicit ReadOnlyFilesDialog(IDocument *document,
                                  QWidget * parent = 0,
                                  bool displaySaveAs = false);
-    explicit ReadOnlyFilesDialog(const QList<IDocument *> documents,
+    explicit ReadOnlyFilesDialog(const QList<IDocument *> &documents,
                                  QWidget * parent = 0);
 
     ~ReadOnlyFilesDialog();
diff --git a/src/plugins/coreplugin/find/searchresulttreemodel.cpp b/src/plugins/coreplugin/find/searchresulttreemodel.cpp
index 7aafe033bbf..8ceac3b6cc7 100644
--- a/src/plugins/coreplugin/find/searchresulttreemodel.cpp
+++ b/src/plugins/coreplugin/find/searchresulttreemodel.cpp
@@ -59,7 +59,7 @@ void SearchResultTreeModel::setShowReplaceUI(bool show)
     m_showReplaceUI = show;
 }
 
-void SearchResultTreeModel::setTextEditorFont(const QFont &font, const SearchResultColor color)
+void SearchResultTreeModel::setTextEditorFont(const QFont &font, const SearchResultColor &color)
 {
     layoutAboutToBeChanged();
     m_textEditorFont = font;
diff --git a/src/plugins/coreplugin/find/searchresulttreemodel.h b/src/plugins/coreplugin/find/searchresulttreemodel.h
index 36ca6d94ac1..8ea988d5928 100644
--- a/src/plugins/coreplugin/find/searchresulttreemodel.h
+++ b/src/plugins/coreplugin/find/searchresulttreemodel.h
@@ -50,7 +50,7 @@ public:
     ~SearchResultTreeModel();
 
     void setShowReplaceUI(bool show);
-    void setTextEditorFont(const QFont &font, const SearchResultColor color);
+    void setTextEditorFont(const QFont &font, const SearchResultColor &color);
 
     Qt::ItemFlags flags(const QModelIndex &index) const;
     QModelIndex index(int row, int column, const QModelIndex &parent = QModelIndex()) const;
diff --git a/src/plugins/coreplugin/find/searchresulttreeview.cpp b/src/plugins/coreplugin/find/searchresulttreeview.cpp
index cb5a7588811..06df77c2027 100644
--- a/src/plugins/coreplugin/find/searchresulttreeview.cpp
+++ b/src/plugins/coreplugin/find/searchresulttreeview.cpp
@@ -58,7 +58,7 @@ void SearchResultTreeView::setAutoExpandResults(bool expand)
     m_autoExpandResults = expand;
 }
 
-void SearchResultTreeView::setTextEditorFont(const QFont &font, const SearchResultColor color)
+void SearchResultTreeView::setTextEditorFont(const QFont &font, const SearchResultColor &color)
 {
     m_model->setTextEditorFont(font, color);
 
diff --git a/src/plugins/coreplugin/find/searchresulttreeview.h b/src/plugins/coreplugin/find/searchresulttreeview.h
index 3d28daaa7fa..f92841ab733 100644
--- a/src/plugins/coreplugin/find/searchresulttreeview.h
+++ b/src/plugins/coreplugin/find/searchresulttreeview.h
@@ -48,7 +48,7 @@ public:
     explicit SearchResultTreeView(QWidget *parent = 0);
 
     void setAutoExpandResults(bool expand);
-    void setTextEditorFont(const QFont &font, const SearchResultColor color);
+    void setTextEditorFont(const QFont &font, const SearchResultColor &color);
 
     SearchResultTreeModel *model() const;
     void addResults(const QList<SearchResultItem> &items, SearchResult::AddMode mode);
diff --git a/src/plugins/coreplugin/find/searchresultwidget.cpp b/src/plugins/coreplugin/find/searchresultwidget.cpp
index b604909b66b..9daca32b7f4 100644
--- a/src/plugins/coreplugin/find/searchresultwidget.cpp
+++ b/src/plugins/coreplugin/find/searchresultwidget.cpp
@@ -341,7 +341,7 @@ void SearchResultWidget::notifyVisibilityChanged(bool visible)
     emit visibilityChanged(visible);
 }
 
-void SearchResultWidget::setTextEditorFont(const QFont &font, const SearchResultColor color)
+void SearchResultWidget::setTextEditorFont(const QFont &font, const SearchResultColor &color)
 {
     m_searchResultTreeView->setTextEditorFont(font, color);
 }
diff --git a/src/plugins/coreplugin/find/searchresultwidget.h b/src/plugins/coreplugin/find/searchresultwidget.h
index 88bdbaef266..34f083de30f 100644
--- a/src/plugins/coreplugin/find/searchresultwidget.h
+++ b/src/plugins/coreplugin/find/searchresultwidget.h
@@ -79,7 +79,7 @@ public:
 
     void notifyVisibilityChanged(bool visible);
 
-    void setTextEditorFont(const QFont &font, const SearchResultColor color);
+    void setTextEditorFont(const QFont &font, const SearchResultColor &color);
 
     void setAutoExpandResults(bool expand);
     void expandAll();
diff --git a/src/plugins/coreplugin/styleanimator.cpp b/src/plugins/coreplugin/styleanimator.cpp
index 07b5ef2e57f..7a283510fe7 100644
--- a/src/plugins/coreplugin/styleanimator.cpp
+++ b/src/plugins/coreplugin/styleanimator.cpp
@@ -48,7 +48,7 @@ void Animation::paint(QPainter *painter, const QStyleOption *option)
     Q_UNUSED(painter)
 }
 
-void Animation::drawBlendedImage(QPainter *painter, QRect rect, float alpha)
+void Animation::drawBlendedImage(QPainter *painter, const QRect &rect, float alpha)
 {
     if (m_secondaryImage.isNull() || m_primaryImage.isNull())
         return;
diff --git a/src/plugins/coreplugin/styleanimator.h b/src/plugins/coreplugin/styleanimator.h
index a3aed0d04da..c474dc6f5d6 100644
--- a/src/plugins/coreplugin/styleanimator.h
+++ b/src/plugins/coreplugin/styleanimator.h
@@ -58,7 +58,7 @@ public :
     virtual void paint(QPainter *painter, const QStyleOption *option);
 
 protected:
-    void drawBlendedImage(QPainter *painter, QRect rect, float value);
+    void drawBlendedImage(QPainter *painter, const QRect &rect, float value);
     QTime m_startTime;
     QPointer<QWidget> m_widget;
     QImage m_primaryImage;