diff --git a/src/app/main.cpp b/src/app/main.cpp
index e1800de1f11d822f1a02ff392ea40e858d4573f7..5199c7c7e64e8f2f6185ba0525137a85d6fadebe 100644
--- a/src/app/main.cpp
+++ b/src/app/main.cpp
@@ -46,7 +46,7 @@
 #include <QtGui/QApplication>
 #include <QtGui/QMainWindow>
 
-#ifdef Q_OS_DARWIN
+#ifdef Q_OS_MAC
 #  include <sys/resource.h>
 #endif
 
@@ -71,7 +71,7 @@ static const char *CLIENT_OPTION = "-client";
 typedef QList<ExtensionSystem::PluginSpec *> PluginSpecSet;
 
 // Helpers for displaying messages. Note that there is no console on Windows.
-#ifdef Q_WS_WIN
+#ifdef Q_OS_WIN
 // Format as <pre> HTML
 static inline void toHtml(QString &t)
 {
@@ -204,7 +204,7 @@ static inline QStringList getPluginPaths()
 
 int main(int argc, char **argv)
 {
-#ifdef Q_OS_DARWIN
+#ifdef Q_OS_MAC
     // increase the number of file that can be opened in Qt Creator.
     struct rlimit rl;
     getrlimit(RLIMIT_NOFILE, &rl);
diff --git a/src/libs/utils/abstractprocess.h b/src/libs/utils/abstractprocess.h
index b7edcd889ec9cfe20a0184e776306c02b8994928..db24b0ca4e5147de3dc1dd10fd00368d63dc6109 100644
--- a/src/libs/utils/abstractprocess.h
+++ b/src/libs/utils/abstractprocess.h
@@ -59,7 +59,7 @@ public:
 //signals:
     virtual void processError(const QString &error) = 0;
 
-#ifdef Q_WS_WIN
+#ifdef Q_OS_WIN
     // Add PATH and SystemRoot environment variables in case they are missing
     static QStringList fixWinEnvironment(const QStringList &env);
     // Quote a Windows command line correctly for the "CreateProcess" API
diff --git a/src/libs/utils/pathchooser.cpp b/src/libs/utils/pathchooser.cpp
index efc49881c98b10d901721a873678af1413425ae9..be494fb5aff8a6fcd7012335e2d20a5d02a640ff 100644
--- a/src/libs/utils/pathchooser.cpp
+++ b/src/libs/utils/pathchooser.cpp
@@ -44,11 +44,10 @@
 #include <QtGui/QToolButton>
 #include <QtGui/QPushButton>
 
-#ifdef Q_OS_MAC
 /*static*/ const char * const Core::Utils::PathChooser::browseButtonLabel =
+#ifdef Q_WS_MAC
                    QT_TRANSLATE_NOOP("Core::Utils::PathChooser", "Choose...");
 #else
-/*static*/ const char * const Core::Utils::PathChooser::browseButtonLabel =
                    QT_TRANSLATE_NOOP("Core::Utils::PathChooser", "Browse...");
 #endif
 
@@ -128,7 +127,7 @@ PathChooser::~PathChooser()
 
 void PathChooser::addButton(const QString &text, QObject *receiver, const char *slotFunc)
 {
-#ifdef Q_OS_MAC
+#ifdef Q_WS_MAC
     QPushButton *button = new QPushButton;
 #else
     QToolButton *button = new QToolButton;
diff --git a/src/plugins/bookmarks/bookmarksplugin.cpp b/src/plugins/bookmarks/bookmarksplugin.cpp
index 3d5cdf2bda874fbf36e663b621c3fd5744854b49..ab1d5239c2c2bf0860c7d34793a8c4c2940932a3 100644
--- a/src/plugins/bookmarks/bookmarksplugin.cpp
+++ b/src/plugins/bookmarks/bookmarksplugin.cpp
@@ -86,7 +86,7 @@ bool BookmarksPlugin::initialize(const QStringList & /*arguments*/, QString *)
     m_toggleAction = new QAction(tr("Toggle Bookmark"), this);
     Core::Command *cmd =
         am->registerAction(m_toggleAction, BOOKMARKS_TOGGLE_ACTION, textcontext);
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     cmd->setDefaultKeySequence(QKeySequence(tr("Ctrl+M")));
 #else
     cmd->setDefaultKeySequence(QKeySequence(tr("Meta+M")));
@@ -116,7 +116,7 @@ bool BookmarksPlugin::initialize(const QStringList & /*arguments*/, QString *)
     //Previous
     m_prevAction = new QAction(tr("Previous Bookmark"), this);
     cmd = am->registerAction(m_prevAction, BOOKMARKS_PREV_ACTION, globalcontext);
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     cmd->setDefaultKeySequence(QKeySequence(tr("Ctrl+,")));
 #else
     cmd->setDefaultKeySequence(QKeySequence(tr("Meta+,")));
@@ -126,7 +126,7 @@ bool BookmarksPlugin::initialize(const QStringList & /*arguments*/, QString *)
     //Next
     m_nextAction = new QAction(tr("Next Bookmark"), this);
     cmd = am->registerAction(m_nextAction, BOOKMARKS_NEXT_ACTION, globalcontext);
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     cmd->setDefaultKeySequence(QKeySequence(tr("Ctrl+.")));
 #else
     cmd->setDefaultKeySequence(QKeySequence(tr("Meta+.")));
diff --git a/src/plugins/coreplugin/actionmanager/actionmanager.cpp b/src/plugins/coreplugin/actionmanager/actionmanager.cpp
index 608956623e1379d0f14e7250174be0046721299b..304f7cf12f2a57fc4e1ccd6b32e2c0f1c7cda43a 100644
--- a/src/plugins/coreplugin/actionmanager/actionmanager.cpp
+++ b/src/plugins/coreplugin/actionmanager/actionmanager.cpp
@@ -361,7 +361,7 @@ Command *ActionManagerPrivate::registerOverridableAction(QAction *action, const
         baseAction->setEnabled(false);
         baseAction->setObjectName(id);
         baseAction->setParent(m_mainWnd);
-#ifdef Q_OS_MAC
+#ifdef Q_WS_MAC
         baseAction->setIconVisibleInMenu(false);
 #endif
         a->setAction(baseAction);
diff --git a/src/plugins/coreplugin/editormanager/editormanager.cpp b/src/plugins/coreplugin/editormanager/editormanager.cpp
index e4edc05d2beb59c958c48c22c4a565619496b39a..364098b63bb16d03dbe7ad33e754fc888145d840 100644
--- a/src/plugins/coreplugin/editormanager/editormanager.cpp
+++ b/src/plugins/coreplugin/editormanager/editormanager.cpp
@@ -344,7 +344,7 @@ EditorManager::EditorManager(ICore *core, QWidget *parent) :
 
     m_d->m_splitAction = new QAction(tr("Split"), this);
     cmd = am->registerAction(m_d->m_splitAction, Constants::SPLIT, editManagerContext);
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     cmd->setDefaultKeySequence(QKeySequence(tr("Ctrl+E,2")));
 #endif
     mwindow->addAction(cmd, Constants::G_WINDOW_SPLIT);
@@ -352,7 +352,7 @@ EditorManager::EditorManager(ICore *core, QWidget *parent) :
 
     m_d->m_splitSideBySideAction = new QAction(tr("Split Side by Side"), this);
     cmd = am->registerAction(m_d->m_splitSideBySideAction, Constants::SPLIT_SIDE_BY_SIDE, editManagerContext);
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     cmd->setDefaultKeySequence(QKeySequence(tr("Ctrl+E,3")));
 #endif
     mwindow->addAction(cmd, Constants::G_WINDOW_SPLIT);
@@ -360,7 +360,7 @@ EditorManager::EditorManager(ICore *core, QWidget *parent) :
 
     m_d->m_removeCurrentSplitAction = new QAction(tr("Remove Current Split"), this);
     cmd = am->registerAction(m_d->m_removeCurrentSplitAction, Constants::REMOVE_CURRENT_SPLIT, editManagerContext);
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     cmd->setDefaultKeySequence(QKeySequence(tr("Ctrl+E,0")));
 #endif
     mwindow->addAction(cmd, Constants::G_WINDOW_SPLIT);
@@ -368,7 +368,7 @@ EditorManager::EditorManager(ICore *core, QWidget *parent) :
 
     m_d->m_removeAllSplitsAction = new QAction(tr("Remove All Splits"), this);
     cmd = am->registerAction(m_d->m_removeAllSplitsAction, Constants::REMOVE_ALL_SPLITS, editManagerContext);
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     cmd->setDefaultKeySequence(QKeySequence(tr("Ctrl+E,1")));
 #endif
     mwindow->addAction(cmd, Constants::G_WINDOW_SPLIT);
@@ -376,7 +376,7 @@ EditorManager::EditorManager(ICore *core, QWidget *parent) :
 
     m_d->m_gotoOtherSplitAction = new QAction(tr("Goto Other Split"), this);
     cmd = am->registerAction(m_d->m_gotoOtherSplitAction, Constants::GOTO_OTHER_SPLIT, editManagerContext);
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     cmd->setDefaultKeySequence(QKeySequence(tr("Ctrl+E,o")));
 #endif
     mwindow->addAction(cmd, Constants::G_WINDOW_SPLIT);
diff --git a/src/plugins/coreplugin/fancyactionbar.cpp b/src/plugins/coreplugin/fancyactionbar.cpp
index b14491ae726b01660d791afaabfe76b1e83a1f4e..318cf82ff3a5dcca269bde703db25db522c51593 100644
--- a/src/plugins/coreplugin/fancyactionbar.cpp
+++ b/src/plugins/coreplugin/fancyactionbar.cpp
@@ -85,7 +85,7 @@ void FancyToolButton::paintEvent(QPaintEvent *event)
     QPainter p(this);
     p.drawPicture(0, 0, m_buttonElements.value(svgIdButtonBase));
     p.drawPicture(0, 0, m_buttonElements.value(isDown() ? svgIdButtonPressedBase : svgIdButtonNormalBase));
-#ifndef Q_WS_MAC // Mac UI's dont usually do hover
+#ifndef Q_WS_MAC // Mac UIs usually don't hover
     if (underMouse() && isEnabled())
         p.drawPicture(0, 0, m_buttonElements.value(svgIdButtonHoverOverlay));
 #endif
diff --git a/src/plugins/coreplugin/fileiconprovider.cpp b/src/plugins/coreplugin/fileiconprovider.cpp
index b5926a951ebb0fbb3bc63239c8872f488440ebed..34a58d574400930e66f131f92ea5ccfaec4e5813 100644
--- a/src/plugins/coreplugin/fileiconprovider.cpp
+++ b/src/plugins/coreplugin/fileiconprovider.cpp
@@ -70,7 +70,7 @@ QIcon FileIconProvider::icon(const QFileInfo &fileInfo)
 
         // Disabled since for now we'll make sure that all icons fit with our
         // own custom icons by returning an empty one if we don't know it.
-#ifdef Q_OS_WIN
+#ifdef Q_WS_WIN
         // This is incorrect if the OS does not always return the same icon for the
         // same suffix (Mac OS X), but should speed up the retrieval a lot ...
         icon = m_systemIconProvider.icon(fileInfo);
@@ -123,7 +123,7 @@ void FileIconProvider::registerIconOverlayForSuffix(const QIcon &icon, const QSt
 QIcon FileIconProvider::iconForSuffix(const QString &suffix) const
 {
     QIcon icon;
-#ifndef Q_OS_WIN // On windows we use the file system icons
+#ifndef Q_WS_WIN // On windows we use the file system icons
     if (suffix.isEmpty())
         return icon;
 
diff --git a/src/plugins/coreplugin/mainwindow.cpp b/src/plugins/coreplugin/mainwindow.cpp
index 07ff1132942d1e89c3d634dfe263438db15c69c2..3520bd0cd88a6db252820867aef01927f18b63c1 100644
--- a/src/plugins/coreplugin/mainwindow.cpp
+++ b/src/plugins/coreplugin/mainwindow.cpp
@@ -144,7 +144,7 @@ MainWindow::MainWindow() :
     m_optionsAction(0),
     m_toggleSideBarAction(0),
     m_toggleFullScreenAction(0),
-#ifdef Q_OS_MAC
+#ifdef Q_WS_MAC
     m_minimizeAction(0),
     m_zoomAction(0),
 #endif
@@ -153,7 +153,7 @@ MainWindow::MainWindow() :
     OutputPaneManager::create();
 
     setWindowTitle(tr("Qt Creator"));
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     qApp->setWindowIcon(QIcon(":/core/images/qtcreator_logo_128.png"));
 #endif
     QCoreApplication::setApplicationName(QLatin1String("QtCreator"));
@@ -597,7 +597,7 @@ void MainWindow::registerDefaultActions()
     // Save As Action
     tmpaction = new QAction(tr("Save &As..."), this);
     cmd = am->registerAction(tmpaction, Constants::SAVEAS, m_globalContext);
-#ifdef Q_OS_MAC
+#ifdef Q_WS_MAC
     cmd->setDefaultKeySequence(QKeySequence(tr("Ctrl+Shift+S")));
 #endif
     cmd->setAttribute(Command::CA_UpdateText);
@@ -607,7 +607,7 @@ void MainWindow::registerDefaultActions()
     // SaveAll Action
     m_saveAllAction = new QAction(tr("Save A&ll"), this);
     cmd = am->registerAction(m_saveAllAction, Constants::SAVEALL, m_globalContext);
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     cmd->setDefaultKeySequence(QKeySequence(tr("Ctrl+Shift+S")));
 #endif
     mfile->addAction(cmd, Constants::G_FILE_SAVE);
@@ -681,13 +681,13 @@ void MainWindow::registerDefaultActions()
     // Options Action
     m_optionsAction = new QAction(tr("&Options..."), this);
     cmd = am->registerAction(m_optionsAction, Constants::OPTIONS, m_globalContext);
-#ifdef Q_OS_MAC
+#ifdef Q_WS_MAC
     cmd->setDefaultKeySequence(QKeySequence("Ctrl+,"));
 #endif
     mtools->addAction(cmd, Constants::G_DEFAULT_THREE);
     connect(m_optionsAction, SIGNAL(triggered()), this, SLOT(showOptionsDialog()));
 
-#ifdef Q_OS_MAC
+#ifdef Q_WS_MAC
     // Minimize Action
     m_minimizeAction = new QAction(tr("Minimize"), this);
     cmd = am->registerAction(m_minimizeAction, Constants::MINIMIZE_WINDOW, m_globalContext);
@@ -711,7 +711,7 @@ void MainWindow::registerDefaultActions()
                                         tr("Show Sidebar"), this);
     m_toggleSideBarAction->setCheckable(true);
     cmd = am->registerAction(m_toggleSideBarAction, Constants::TOGGLE_SIDEBAR, m_globalContext);
-#ifdef Q_OS_MAC
+#ifdef Q_WS_MAC
     cmd->setDefaultKeySequence(QKeySequence("Ctrl+0"));
 #else
     cmd->setDefaultKeySequence(QKeySequence("Alt+0"));
@@ -721,7 +721,7 @@ void MainWindow::registerDefaultActions()
     mwindow->addAction(cmd, Constants::G_WINDOW_PANES);
     m_toggleSideBarAction->setEnabled(false);
 
-#if !defined(Q_OS_MAC)
+#ifndef Q_WS_MAC
     // Full Screen Action
     m_toggleFullScreenAction = new QAction(tr("Full Screen"), this);
     m_toggleFullScreenAction->setCheckable(true);
@@ -732,7 +732,7 @@ void MainWindow::registerDefaultActions()
 #endif
 
     // About IDE Action
-#ifdef Q_OS_MAC
+#ifdef Q_WS_MAC
     tmpaction = new QAction(tr("About &Qt Creator"), this); // it's convention not to add dots to the about menu
 #else
     tmpaction = new QAction(tr("About &Qt Creator..."), this);
@@ -746,7 +746,7 @@ void MainWindow::registerDefaultActions()
     cmd = am->registerAction(tmpaction, Constants::ABOUT_PLUGINS, m_globalContext);
     mhelp->addAction(cmd, Constants::G_HELP_ABOUT);
     tmpaction->setEnabled(true);
-#ifdef Q_OS_MAC
+#ifdef Q_WS_MAC
     cmd->action()->setMenuRole(QAction::ApplicationSpecificRole);
 #endif
     connect(tmpaction, SIGNAL(triggered()), this,  SLOT(aboutPlugins()));
@@ -1022,7 +1022,7 @@ void MainWindow::changeEvent(QEvent *e)
             emit windowActivated();
         }
     } else if (e->type() == QEvent::WindowStateChange) {
-#ifdef Q_OS_MAC
+#ifdef Q_WS_MAC
         bool minimized = isMinimized();
         if (debugMainWindow)
             qDebug() << "main window state changed to minimized=" << minimized;
diff --git a/src/plugins/coreplugin/mainwindow.h b/src/plugins/coreplugin/mainwindow.h
index 7886d7795d1c311ab285ef6124f834e671faa835..997a0c26d9e97bc77eaf7d2e12cf7b33632759b6 100644
--- a/src/plugins/coreplugin/mainwindow.h
+++ b/src/plugins/coreplugin/mainwindow.h
@@ -208,7 +208,7 @@ private:
     QAction *m_optionsAction;
     QAction *m_toggleSideBarAction;
     QAction *m_toggleFullScreenAction;
-#ifdef Q_OS_MAC
+#ifdef Q_WS_MAC
     QAction *m_minimizeAction;
     QAction *m_zoomAction;
 #endif
diff --git a/src/plugins/coreplugin/modemanager.cpp b/src/plugins/coreplugin/modemanager.cpp
index f54a9378a6b3455ce01c56424bad84c202a59d20..d514aa0022de33a40f43ae85b11e888d1916661f 100644
--- a/src/plugins/coreplugin/modemanager.cpp
+++ b/src/plugins/coreplugin/modemanager.cpp
@@ -147,7 +147,7 @@ void ModeManager::objectAdded(QObject *obj)
     m_modeShortcuts.insert(index, cmd);
     connect(cmd, SIGNAL(keySequenceChanged()), this, SLOT(updateModeToolTip()));
     for (int i = 0; i < m_modeShortcuts.size(); ++i) {
-#ifdef Q_OS_MAC
+#ifdef Q_WS_MAC
         m_modeShortcuts.at(i)->setDefaultKeySequence(QKeySequence(QString("Meta+%1").arg(i+1)));
 #else
         m_modeShortcuts.at(i)->setDefaultKeySequence(QKeySequence(QString("Ctrl+%1").arg(i+1)));
diff --git a/src/plugins/coreplugin/navigationwidget.cpp b/src/plugins/coreplugin/navigationwidget.cpp
index 091d19c2510a272003b36721a274cc0b1c3846b6..d93abca335e46fc2a752425710fccfd9f94ec517 100644
--- a/src/plugins/coreplugin/navigationwidget.cpp
+++ b/src/plugins/coreplugin/navigationwidget.cpp
@@ -363,7 +363,7 @@ NavigationSubWidget::NavigationSubWidget(NavigationWidget *parentWidget)
 
     m_navigationComboBox = new NavComboBox(this);
     m_navigationWidget = 0;
-#ifdef Q_OS_MAC
+#ifdef Q_WS_MAC
     // this is to avoid ugly tool bar behavior
     m_navigationComboBox->setMaximumWidth(130);
 #endif
diff --git a/src/plugins/coreplugin/outputpane.cpp b/src/plugins/coreplugin/outputpane.cpp
index 685327c55927f0849072e90d45f89d15d19d1a1c..ba27f6771afdb1fa9aa76eb83cf32b2a5beb6481 100644
--- a/src/plugins/coreplugin/outputpane.cpp
+++ b/src/plugins/coreplugin/outputpane.cpp
@@ -207,7 +207,7 @@ OutputPaneManager::OutputPaneManager(QWidget *parent) :
     m_buttonsWidget = new QWidget;
     m_buttonsWidget->setLayout(new QHBoxLayout);
     m_buttonsWidget->layout()->setContentsMargins(5,0,0,0);
-#ifdef Q_OS_MAC
+#ifdef Q_WS_MAC
     m_buttonsWidget->layout()->setSpacing(16);
 #else
     m_buttonsWidget->layout()->setSpacing(4);
@@ -299,7 +299,7 @@ void OutputPaneManager::init()
 
         Command *cmd = am->registerAction(action, actionId, QList<int>() << Constants::C_GLOBAL_ID);
         if (outPane->priorityInStatusBar() != -1) {
-#ifdef Q_OS_MAC
+#ifdef Q_WS_MAC
             cmd->setDefaultKeySequence(QKeySequence(paneShortCut(Qt::CTRL, shortcutNumber)));
 #else
             cmd->setDefaultKeySequence(QKeySequence(paneShortCut(Qt::ALT, shortcutNumber)));
@@ -567,7 +567,7 @@ OutputPaneToggleButton::OutputPaneToggleButton(int number, const QString &text,
             "QPushButton { border-image: url(:/core/images/panel_button.png) 2 2 2 19;"
                          " border-width: 2px 2px 2px 19px; padding-left: -17; padding-right: 4 } "
             "QPushButton:checked { border-image: url(:/core/images/panel_button_checked.png) 2 2 2 19 } "
-#ifndef Q_WS_MAC // Mac UI's dont usually do hover
+#ifndef Q_WS_MAC // Mac UIs usually don't hover
             "QPushButton:checked:hover { border-image: url(:/core/images/panel_button_checked_hover.png) 2 2 2 19 } "
             "QPushButton:pressed:hover { border-image: url(:/core/images/panel_button_pressed.png) 2 2 2 19 } "
             "QPushButton:hover { border-image: url(:/core/images/panel_button_hover.png) 2 2 2 19 } "
diff --git a/src/plugins/coreplugin/stylehelper.cpp b/src/plugins/coreplugin/stylehelper.cpp
index b46f751e009da3662996a643b055711597532c38..42ca012cf31f78f98e46c5615dd45a3068437e34 100644
--- a/src/plugins/coreplugin/stylehelper.cpp
+++ b/src/plugins/coreplugin/stylehelper.cpp
@@ -50,7 +50,7 @@ static int range(float x, int min, int max)
 
 qreal StyleHelper::sidebarFontSize()
 {
-#if defined(Q_OS_MAC)
+#if defined(Q_WS_MAC)
     return 9;
 #else
     return 7.5;
diff --git a/src/plugins/cpaster/cpasterplugin.cpp b/src/plugins/cpaster/cpasterplugin.cpp
index 6af357ca8057c24a39b3f384969fe4e3728a9ae0..f407e1b100028c49b2602ae30bb36d03b545a75f 100644
--- a/src/plugins/cpaster/cpasterplugin.cpp
+++ b/src/plugins/cpaster/cpasterplugin.cpp
@@ -100,7 +100,7 @@ bool CodepasterPlugin::initialize(const QStringList &arguments, QString *error_m
 
     m_postAction = new QAction(tr("Paste Snippet..."), this);
     command = actionManager->registerAction(m_postAction, "CodePaster.Post", globalcontext);
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     command->setDefaultKeySequence(QKeySequence(tr("Alt+C,Alt+P")));
 #endif
     connect(m_postAction, SIGNAL(triggered()), this, SLOT(post()));
@@ -108,7 +108,7 @@ bool CodepasterPlugin::initialize(const QStringList &arguments, QString *error_m
 
     m_fetchAction = new QAction(tr("Fetch Snippet..."), this);
     command = actionManager->registerAction(m_fetchAction, "CodePaster.Fetch", globalcontext);
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     command->setDefaultKeySequence(QKeySequence(tr("Alt+C,Alt+F")));
 #endif
     connect(m_fetchAction, SIGNAL(triggered()), this, SLOT(fetch()));
diff --git a/src/plugins/cpptools/cppcodecompletion.cpp b/src/plugins/cpptools/cppcodecompletion.cpp
index 384058685b5588ecc7518d75cfa83dcb7269fde1..d69d683f819a6fb39b0416d0ed6a2e6974f98988 100644
--- a/src/plugins/cpptools/cppcodecompletion.cpp
+++ b/src/plugins/cpptools/cppcodecompletion.cpp
@@ -405,7 +405,7 @@ void FunctionArgumentWidget::updateHintText()
     m_popupFrame->setFixedWidth(m_popupFrame->minimumSizeHint().width());
 
     const QDesktopWidget *desktop = QApplication::desktop();
-#ifdef Q_OS_MAC
+#ifdef Q_WS_MAC
     const QRect screen = desktop->availableGeometry(desktop->screenNumber(m_editor->widget()));
 #else
     const QRect screen = desktop->screenGeometry(desktop->screenNumber(m_editor->widget()));
diff --git a/src/plugins/debugger/debuggerplugin.cpp b/src/plugins/debugger/debuggerplugin.cpp
index d252b2482da5606d329cc7a6eb7db0da2fcbe880..60db690d214b31fe662f6ff77f0f520f8a426af2 100644
--- a/src/plugins/debugger/debuggerplugin.cpp
+++ b/src/plugins/debugger/debuggerplugin.cpp
@@ -112,7 +112,7 @@ const char * const BREAK_BY_FUNCTION    = "Debugger.BreakByFunction";
 const char * const BREAK_AT_MAIN        = "Debugger.BreakAtMain";
 const char * const ADD_TO_WATCH         = "Debugger.AddToWatch";
 
-#ifdef Q_OS_MAC
+#ifdef Q_WS_MAC
 const char * const INTERRUPT_KEY            = "Shift+F5";
 const char * const RESET_KEY                = "Ctrl+Shift+F5";
 const char * const STEP_KEY                 = "F7";
@@ -1136,7 +1136,7 @@ void DebuggerPlugin::readSettings()
     DebuggerSettings::instance()->readSettings(s);
 
     QString defaultCommand("gdb");
-#if defined(Q_OS_WIN32)
+#ifdef Q_OS_WIN
     defaultCommand.append(".exe");
 #endif
     //QString defaultScript = ICore::instance()->resourcePath() +
diff --git a/src/plugins/debugger/gdb/gdbengine.cpp b/src/plugins/debugger/gdb/gdbengine.cpp
index 770586af681142590cd6eccfb8cc14281397065f..9b0ae33cf80741490a13e3c191db4ab8ca60c7bb 100644
--- a/src/plugins/debugger/gdb/gdbengine.cpp
+++ b/src/plugins/debugger/gdb/gdbengine.cpp
@@ -72,7 +72,7 @@
 #    include "shared/sharedlibraryinjector.h"
 #endif
 
-#if defined(Q_OS_LINUX) || defined(Q_OS_MAC)
+#ifdef Q_OS_UNIX
 #include <unistd.h>
 #include <dlfcn.h>
 #endif
@@ -826,12 +826,10 @@ void GdbEngine::handleInfoThreads(const GdbResultRecord &record, const QVariant
 void GdbEngine::handleInfoProc(const GdbResultRecord &record, const QVariant &)
 {
     if (record.resultClass == GdbResultDone) {
-        #if defined(Q_OS_MAC)
+        #ifdef Q_OS_MAC
         //^done,process-id="85075"
         maybeHandleInferiorPidChanged(_(record.data.findChild("process-id").data()));
-        #endif
-
-        #if defined(Q_OS_LINUX) || defined(Q_OS_WIN)
+        #else
         // FIXME: use something more robust
         QRegExp re(__("process (\\d+)"));
         QString data = __(record.data.findChild("consolestreamoutput").data());
@@ -919,14 +917,12 @@ static bool isStoppedReason(const QByteArray &reason)
 
 void GdbEngine::handleAqcuiredInferior()
 {
-    #if defined(Q_OS_WIN)
+    #ifdef Q_OS_WIN
     postCommand(_("info thread"), CB(handleInfoThreads));
-    #endif
-    #if defined(Q_OS_LINUX)
-    postCommand(_("info proc"), CB(handleInfoProc));
-    #endif
-    #if defined(Q_OS_MAC)
+    #elif defined(Q_OS_MAC)
     postCommand(_("info pid"), NeedsStop, CB(handleInfoProc));
+    #else
+    postCommand(_("info proc"), CB(handleInfoProc));
     #endif
     if (theDebuggerBoolSetting(ListSourceFiles))
         reloadSourceFiles();
@@ -1883,22 +1879,20 @@ void GdbEngine::sendInsertBreakpoint(int index)
 
     // set up fallback in case of pending breakpoints which aren't handled
     // by the MI interface
-#if defined(Q_OS_UNIX) && !defined(Q_OS_MAC)
-    QString cmd = _("-break-insert -f ");
+#if defined(Q_OS_WIN)
+    QString cmd = _("-break-insert ");
     //if (!data->condition.isEmpty())
-    //    cmd += _("-c ") + data->condition + ' ';
+    //    cmd += "-c " + data->condition + " ";
     cmd += where;
-#endif
-#if defined(Q_OS_MAC)
+#elif defined(Q_OS_MAC)
     QString cmd = _("-break-insert -l -1 ");
     //if (!data->condition.isEmpty())
     //    cmd += "-c " + data->condition + " ";
     cmd += where;
-#endif
-#if defined(Q_OS_WIN)
-    QString cmd = _("-break-insert ");
+#else
+    QString cmd = _("-break-insert -f ");
     //if (!data->condition.isEmpty())
-    //    cmd += "-c " + data->condition + " ";
+    //    cmd += _("-c ") + data->condition + ' ';
     cmd += where;
 #endif
     debugMessage(_("Current state: %1").arg(q->status()));
@@ -2039,24 +2033,22 @@ void GdbEngine::handleBreakInsert(const GdbResultRecord &record, const QVariant
         const BreakpointData *data = handler->at(index);
         // Note that it is perfectly correct that the file name is put
         // in quotes but not escaped. GDB simply is like that.
-#if defined(Q_OS_UNIX) && !defined(Q_OS_MAC)
-        //QString where = "\"\\\"" + data->fileName + "\\\":"
-        //    + data->lineNumber + "\"";
-        QString where = _c('"') + data->fileName + _("\":")
-            + data->lineNumber;
-        // Should not happen with -break-insert -f. gdb older than 6.8?
-        QTC_ASSERT(false, /**/);
-#endif
-#if defined(Q_OS_MAC)
+#if defined(Q_OS_WIN)
         QFileInfo fi(data->fileName);
         QString where = _c('"') + fi.fileName() + _("\":")
             + data->lineNumber;
-#endif
-#if defined(Q_OS_WIN)
+        //QString where = m_data->fileName + _c(':') + data->lineNumber;
+#elif defined(Q_OS_MAC)
         QFileInfo fi(data->fileName);
         QString where = _c('"') + fi.fileName() + _("\":")
             + data->lineNumber;
-        //QString where = m_data->fileName + _c(':') + data->lineNumber;
+#else
+        //QString where = "\"\\\"" + data->fileName + "\\\":"
+        //    + data->lineNumber + "\"";
+        QString where = _c('"') + data->fileName + _("\":")
+            + data->lineNumber;
+        // Should not happen with -break-insert -f. gdb older than 6.8?
+        QTC_ASSERT(false, /**/);
 #endif
         postCommand(_("break ") + where, CB(handleBreakInsert1), index);
     }
diff --git a/src/plugins/debugger/stackwindow.cpp b/src/plugins/debugger/stackwindow.cpp
index e51c27ac6d311fd66ab6287fcfc7e8004e7bcbc7..9354dda80680582f622e5fffb3cf1ba42992b203 100644
--- a/src/plugins/debugger/stackwindow.cpp
+++ b/src/plugins/debugger/stackwindow.cpp
@@ -133,7 +133,7 @@ void StackWindow::copyContentsToClipboard()
         str += '\n';
     }
     QClipboard *clipboard = QApplication::clipboard();
-    #ifdef Q_OS_LINUX
+    #ifdef Q_WS_X11
     clipboard->setText(str, QClipboard::Selection);
     #endif
     clipboard->setText(str, QClipboard::Clipboard);
diff --git a/src/plugins/find/findtoolbar.cpp b/src/plugins/find/findtoolbar.cpp
index 313d229ceb869d7f4bf30df3c825c1f60a0472eb..2dff2fdc37896b4fcefdee9fc6b2f89bae3b0b9b 100644
--- a/src/plugins/find/findtoolbar.cpp
+++ b/src/plugins/find/findtoolbar.cpp
@@ -240,7 +240,7 @@ bool FindToolBar::eventFilter(QObject *obj, QEvent *event)
     if ((obj == m_ui.findEdit || obj == m_findCompleter->popup())
                && event->type() == QEvent::KeyPress) {
         QKeyEvent *ke = static_cast<QKeyEvent *>(event);
-#ifdef Q_OS_MAC
+#ifdef Q_WS_MAC
         if (ke->key() == Qt::Key_Space && (ke->modifiers() & Qt::MetaModifier)) {
 #else
         if (ke->key() == Qt::Key_Space && (ke->modifiers() & Qt::ControlModifier)) {
@@ -261,7 +261,7 @@ bool FindToolBar::eventFilter(QObject *obj, QEvent *event)
                 event->accept();
                 return true;
             }
-#ifdef Q_OS_MAC
+#ifdef Q_WS_MAC
         } else if (ke->key() == Qt::Key_Space && (ke->modifiers() & Qt::MetaModifier)) {
 #else
         } else if (ke->key() == Qt::Key_Space && (ke->modifiers() & Qt::ControlModifier)) {
diff --git a/src/plugins/git/gitplugin.cpp b/src/plugins/git/gitplugin.cpp
index 4f240a21fe8111e15af6a90bb651bf03de184d31..ac3cfb2d2d8ad91b9923ddfde6b38935ee7e623a 100644
--- a/src/plugins/git/gitplugin.cpp
+++ b/src/plugins/git/gitplugin.cpp
@@ -279,7 +279,7 @@ bool GitPlugin::initialize(const QStringList &arguments, QString *errorMessage)
     m_diffAction = new Core::Utils::ParameterAction(tr("Diff Current File"), tr("Diff \"%1\""), Core::Utils::ParameterAction::AlwaysEnabled, this);
     command = actionManager->registerAction(m_diffAction, "Git.Diff", globalcontext);
     command->setAttribute(Core::Command::CA_UpdateText);
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     command->setDefaultKeySequence(QKeySequence(tr("Alt+G,Alt+D")));
 #endif
     connect(m_diffAction, SIGNAL(triggered()), this, SLOT(diffCurrentFile()));
@@ -287,7 +287,7 @@ bool GitPlugin::initialize(const QStringList &arguments, QString *errorMessage)
 
     m_statusAction = new Core::Utils::ParameterAction(tr("File Status"), tr("Status Related to \"%1\""), Core::Utils::ParameterAction::AlwaysEnabled, this);
     command = actionManager->registerAction(m_statusAction, "Git.Status", globalcontext);
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     command->setDefaultKeySequence(QKeySequence(tr("Alt+G,Alt+S")));
 #endif
     command->setAttribute(Core::Command::CA_UpdateText);
@@ -296,7 +296,7 @@ bool GitPlugin::initialize(const QStringList &arguments, QString *errorMessage)
 
     m_logAction = new Core::Utils::ParameterAction(tr("Log File"), tr("Log of \"%1\""), Core::Utils::ParameterAction::AlwaysEnabled, this);
     command = actionManager->registerAction(m_logAction, "Git.Log", globalcontext);
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     command->setDefaultKeySequence(QKeySequence(tr("Alt+G,Alt+L")));
 #endif
     command->setAttribute(Core::Command::CA_UpdateText);
@@ -305,7 +305,7 @@ bool GitPlugin::initialize(const QStringList &arguments, QString *errorMessage)
 
     m_blameAction = new Core::Utils::ParameterAction(tr("Blame"), tr("Blame for \"%1\""), Core::Utils::ParameterAction::AlwaysEnabled, this);
     command = actionManager->registerAction(m_blameAction, "Git.Blame", globalcontext);
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     command->setDefaultKeySequence(QKeySequence(tr("Alt+G,Alt+B")));
 #endif
     command->setAttribute(Core::Command::CA_UpdateText);
@@ -314,7 +314,7 @@ bool GitPlugin::initialize(const QStringList &arguments, QString *errorMessage)
 
     m_undoFileAction = new Core::Utils::ParameterAction(tr("Undo Changes"), tr("Undo Changes for \"%1\""),  Core::Utils::ParameterAction::AlwaysEnabled, this);
     command = actionManager->registerAction(m_undoFileAction, "Git.Undo", globalcontext);
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     command->setDefaultKeySequence(QKeySequence(tr("Alt+G,Alt+U")));
 #endif
     command->setAttribute(Core::Command::CA_UpdateText);
@@ -323,7 +323,7 @@ bool GitPlugin::initialize(const QStringList &arguments, QString *errorMessage)
 
     m_stageAction = new Core::Utils::ParameterAction(tr("Stage File for Commit"), tr("Stage \"%1\" for Commit"), Core::Utils::ParameterAction::AlwaysEnabled, this);
     command = actionManager->registerAction(m_stageAction, "Git.Stage", globalcontext);
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     command->setDefaultKeySequence(QKeySequence(tr("Alt+G,Alt+A")));
 #endif
     command->setAttribute(Core::Command::CA_UpdateText);
@@ -346,7 +346,7 @@ bool GitPlugin::initialize(const QStringList &arguments, QString *errorMessage)
 
     m_diffProjectAction = new Core::Utils::ParameterAction(tr("Diff Current Project"), tr("Diff Project \"%1\""), Core::Utils::ParameterAction::AlwaysEnabled, this);
     command = actionManager->registerAction(m_diffProjectAction, "Git.DiffProject", globalcontext);
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     command->setDefaultKeySequence(QKeySequence("Alt+G,Alt+Shift+D"));
 #endif
     command->setAttribute(Core::Command::CA_UpdateText);
@@ -361,7 +361,7 @@ bool GitPlugin::initialize(const QStringList &arguments, QString *errorMessage)
 
     m_logProjectAction = new Core::Utils::ParameterAction(tr("Log Project"), tr("Log Project \"%1\""), Core::Utils::ParameterAction::AlwaysEnabled, this);
     command = actionManager->registerAction(m_logProjectAction, "Git.LogProject", globalcontext);
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     command->setDefaultKeySequence(QKeySequence(tr("Alt+G,Alt+K")));
 #endif
     command->setAttribute(Core::Command::CA_UpdateText);
@@ -398,7 +398,7 @@ bool GitPlugin::initialize(const QStringList &arguments, QString *errorMessage)
 
     m_commitAction = new QAction(tr("Commit..."), this);
     command = actionManager->registerAction(m_commitAction, "Git.Commit", globalcontext);
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     command->setDefaultKeySequence(QKeySequence(tr("Alt+G,Alt+C")));
 #endif
     command->setAttribute(Core::Command::CA_UpdateText);
diff --git a/src/plugins/help/centralwidget.cpp b/src/plugins/help/centralwidget.cpp
index a53a67564ac27adc867763f9b23a7d9fc1fe5ada..72574102f91d8719099b146de13bdd92814cc724 100644
--- a/src/plugins/help/centralwidget.cpp
+++ b/src/plugins/help/centralwidget.cpp
@@ -85,10 +85,10 @@ CentralWidget::CentralWidget(QHelpEngine *engine, QWidget *parent)
     globalActionList.clear();
     collectionFile = helpEngine->collectionFile();
 
-    QString system = QLatin1String("win");
-
 #ifdef Q_OS_MAC
-    system = QLatin1String("mac");
+#   define SYSTEM "mac"
+#else
+#   define SYSTEM "win"
 #endif
 
     tabWidget = new QTabWidget;
@@ -100,7 +100,7 @@ CentralWidget::CentralWidget(QHelpEngine *engine, QWidget *parent)
     QToolButton *newTabButton = new QToolButton(this);
     newTabButton->setAutoRaise(true);
     newTabButton->setToolTip(tr("Add new page"));
-    newTabButton->setIcon(QIcon(QString::fromUtf8(":/trolltech/assistant/images/%1/addtab.png").arg(system)));
+    newTabButton->setIcon(QIcon(QString::fromLatin1(":/trolltech/assistant/images/" SYSTEM "/addtab.png")));
 
     tabWidget->setCornerWidget(newTabButton, Qt::TopLeftCorner);
     connect(newTabButton, SIGNAL(clicked()), this, SLOT(newTab()));
diff --git a/src/plugins/help/helpplugin.cpp b/src/plugins/help/helpplugin.cpp
index 661723464cb84600b3c5857842a65296866a745d..f5287afbd6f2cbad6244f1ad40244895732185c1 100644
--- a/src/plugins/help/helpplugin.cpp
+++ b/src/plugins/help/helpplugin.cpp
@@ -241,7 +241,7 @@ bool HelpPlugin::initialize(const QStringList &arguments, QString *error)
     am->actionContainer(Core::Constants::M_HELP)->addAction(cmd,
         Core::Constants::G_HELP_HELP);
 
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     QAction *sep = new QAction(this);
     sep->setSeparator(true);
     cmd = am->registerAction(sep, QLatin1String("Help.Separator"), globalcontext);
@@ -344,7 +344,7 @@ bool HelpPlugin::initialize(const QStringList &arguments, QString *error)
     actionList << previousAction
         << nextAction
         << homeAction
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
         << sep
 #endif
         << copyAction;
diff --git a/src/plugins/projectexplorer/debugginghelper.cpp b/src/plugins/projectexplorer/debugginghelper.cpp
index da5fefc5125bc9e210e8145645b517015699dc42..b403872f5b200cf6866c52f7de0012c8911b7341 100644
--- a/src/plugins/projectexplorer/debugginghelper.cpp
+++ b/src/plugins/projectexplorer/debugginghelper.cpp
@@ -215,10 +215,11 @@ QStringList DebuggingHelperLibrary::possibleQMakeCommands()
     // On windows noone has renamed qmake, right?
 #ifdef Q_OS_WIN
     return QStringList() << "qmake.exe";
-#endif
+#else
     // On unix some distributions renamed qmake to avoid clashes
     QStringList result;
     result << "qmake-qt4" << "qmake4" << "qmake";
     return result;
+#endif
 }
 
diff --git a/src/plugins/projectexplorer/projecttreewidget.cpp b/src/plugins/projectexplorer/projecttreewidget.cpp
index 32b6ca9edfb3cc11834c2aa2eb175dcc715394ee..8054fa0f8d69f4c5ed6f62a64e025d73aa24acd9 100644
--- a/src/plugins/projectexplorer/projecttreewidget.cpp
+++ b/src/plugins/projectexplorer/projecttreewidget.cpp
@@ -90,7 +90,7 @@ protected:
             QTreeView::focusOutEvent(event);
     }
 
-#ifdef Q_OS_MAC
+#ifdef Q_WS_MAC
     void keyPressEvent(QKeyEvent *event)
     {
         if ((event->key() == Qt::Key_Return
diff --git a/src/plugins/qt4projectmanager/qmakestep.cpp b/src/plugins/qt4projectmanager/qmakestep.cpp
index 3b0049ec4030dc2a77770e2b55c99c75c24dd009..071d30a5ce38c6d4cff10b50fa607b6dcae96815 100644
--- a/src/plugins/qt4projectmanager/qmakestep.cpp
+++ b/src/plugins/qt4projectmanager/qmakestep.cpp
@@ -103,7 +103,7 @@ bool QMakeStep::init(const QString &name)
 
 
     if (!qtVersion->isValid()) {
-#if defined(Q_OS_MAC)
+#if defined(Q_WS_MAC)
         emit addToOutputWindow(tr("\n<font color=\"#ff0000\"><b>No valid Qt version set. Set one in Preferences </b></font>\n"));
 #else
         emit addToOutputWindow(tr("\n<font color=\"#ff0000\"><b>No valid Qt version set. Set one in Tools/Options </b></font>\n"));
diff --git a/src/plugins/qt4projectmanager/qtversionmanager.cpp b/src/plugins/qt4projectmanager/qtversionmanager.cpp
index 761e70612fa38030fcfdff64d1dbf92f1c0139b0..ea64f2da180909c8d0393df574b3d888de2e4ea0 100644
--- a/src/plugins/qt4projectmanager/qtversionmanager.cpp
+++ b/src/plugins/qt4projectmanager/qtversionmanager.cpp
@@ -937,8 +937,7 @@ static inline QStringList possibleGuiBinaries(const QString &name)
 {
 #ifdef Q_OS_WIN
     return QStringList(name + QLatin1String(".exe"));
-#endif
-#ifdef Q_OS_MAC // 'Foo.app/Contents/MacOS/Foo'
+#elif defined(Q_OS_MAC) // 'Foo.app/Contents/MacOS/Foo'
     QString upCaseName = name;
     upCaseName[0] = upCaseName.at(0).toUpper();
     QString macBinary = upCaseName;
diff --git a/src/plugins/subversion/subversionplugin.cpp b/src/plugins/subversion/subversionplugin.cpp
index 532beecdf45f6ac7abd661c67ad9c434e9c4de22..af0e674c1bc070d8eec939ccebd3e79f94db241b 100644
--- a/src/plugins/subversion/subversionplugin.cpp
+++ b/src/plugins/subversion/subversionplugin.cpp
@@ -336,7 +336,7 @@ bool SubversionPlugin::initialize(const QStringList &arguments, QString *errorMe
     command = ami->registerAction(m_addAction, SubversionPlugin::ADD,
         globalcontext);
     command->setAttribute(Core::Command::CA_UpdateText);
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     command->setDefaultKeySequence(QKeySequence(tr("Alt+S,Alt+A")));
 #endif
     connect(m_addAction, SIGNAL(triggered()), this, SLOT(addCurrentFile()));
@@ -368,7 +368,7 @@ bool SubversionPlugin::initialize(const QStringList &arguments, QString *errorMe
     command = ami->registerAction(m_diffCurrentAction,
         SubversionPlugin::DIFF_CURRENT, globalcontext);
     command->setAttribute(Core::Command::CA_UpdateText);
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     command->setDefaultKeySequence(QKeySequence(tr("Alt+S,Alt+D")));
 #endif
     connect(m_diffCurrentAction, SIGNAL(triggered()), this, SLOT(diffCurrentFile()));
@@ -386,7 +386,7 @@ bool SubversionPlugin::initialize(const QStringList &arguments, QString *errorMe
     command = ami->registerAction(m_commitCurrentAction,
         SubversionPlugin::COMMIT_CURRENT, globalcontext);
     command->setAttribute(Core::Command::CA_UpdateText);
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     command->setDefaultKeySequence(QKeySequence(tr("Alt+S,Alt+C")));
 #endif
     connect(m_commitCurrentAction, SIGNAL(triggered()), this, SLOT(startCommitCurrentFile()));
diff --git a/src/plugins/texteditor/basetexteditor.cpp b/src/plugins/texteditor/basetexteditor.cpp
index 44ab1dab1fe8cea10583252006124cd69a96dbee..5448be6d4a388e91f4765878c1f80b73b506ab90 100644
--- a/src/plugins/texteditor/basetexteditor.cpp
+++ b/src/plugins/texteditor/basetexteditor.cpp
@@ -956,7 +956,7 @@ void BaseTextEditor::keyPressEvent(QKeyEvent *e)
     case Qt::Key_End:
     case Qt::Key_Right:
     case Qt::Key_Left:
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
         if ((e->modifiers() & (Qt::AltModifier | Qt::ShiftModifier)) == (Qt::AltModifier | Qt::ShiftModifier)) {
 
             d->m_lastEventWasBlockSelectionEvent = true;
diff --git a/src/plugins/texteditor/completionwidget.cpp b/src/plugins/texteditor/completionwidget.cpp
index 8806fd3d6d5945e783d6aa9096d10ee78636b709..a7d0c2312979b8f1020fa2f38fb9688449224497 100644
--- a/src/plugins/texteditor/completionwidget.cpp
+++ b/src/plugins/texteditor/completionwidget.cpp
@@ -255,7 +255,7 @@ void CompletionWidget::updatePositionAndSize(int startPos)
     // Determine the position, keeping the popup on the screen
     const QRect cursorRect = m_editor->cursorRect(startPos);
     const QDesktopWidget *desktop = QApplication::desktop();
-#ifdef Q_OS_MAC
+#ifdef Q_WS_MAC
     const QRect screen = desktop->availableGeometry(desktop->screenNumber(m_editorWidget));
 #else
     const QRect screen = desktop->screenGeometry(desktop->screenNumber(m_editorWidget));
diff --git a/src/plugins/texteditor/fontsettings.cpp b/src/plugins/texteditor/fontsettings.cpp
index 37907a345e5c4625d5e31af50091f100f172704e..441a7a67113598be734816acf91699c9e4126046 100644
--- a/src/plugins/texteditor/fontsettings.cpp
+++ b/src/plugins/texteditor/fontsettings.cpp
@@ -48,7 +48,7 @@ static const bool DEFAULT_ANTIALIAS = true;
     enum { DEFAULT_FONT_SIZE = 12 };
     static const char *DEFAULT_FONT_FAMILY = "Monaco";
 #else
-#ifdef Q_OS_UNIX
+#ifdef Q_WS_X11
     enum { DEFAULT_FONT_SIZE = 9 };
     static const char *DEFAULT_FONT_FAMILY = "Monospace";
 #else
diff --git a/src/plugins/texteditor/texteditoractionhandler.cpp b/src/plugins/texteditor/texteditoractionhandler.cpp
index 44220bfdb9991004554402000437db773f73ef0c..d8bd9e098e494d1cc57e76da54d185a883377031 100644
--- a/src/plugins/texteditor/texteditoractionhandler.cpp
+++ b/src/plugins/texteditor/texteditoractionhandler.cpp
@@ -146,7 +146,7 @@ void TextEditorActionHandler::createActions()
     m_visualizeWhitespaceAction->setCheckable(true);
     command = am->registerAction(m_visualizeWhitespaceAction,
                                  TextEditor::Constants::VISUALIZE_WHITESPACE, m_contextId);
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     command->setDefaultKeySequence(QKeySequence(tr("Ctrl+E, Ctrl+V")));
 #endif
     advancedMenu->addAction(command, Core::Constants::G_EDIT_FORMAT);
@@ -162,7 +162,7 @@ void TextEditorActionHandler::createActions()
     m_textWrappingAction = new QAction(tr("Enable Text &Wrapping"), this);
     m_textWrappingAction->setCheckable(true);
     command = am->registerAction(m_textWrappingAction, TextEditor::Constants::TEXT_WRAPPING, m_contextId);
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     command->setDefaultKeySequence(QKeySequence(tr("Ctrl+E, Ctrl+W")));
 #endif
     advancedMenu->addAction(command, Core::Constants::G_EDIT_FORMAT);
diff --git a/src/plugins/texteditor/texteditorplugin.cpp b/src/plugins/texteditor/texteditorplugin.cpp
index 049d3a3978061fa52ea78c7aeb173b0384e075a7..b6bf55025bfae1ebba9ee39327b6425ee7a9bcd8 100644
--- a/src/plugins/texteditor/texteditorplugin.cpp
+++ b/src/plugins/texteditor/texteditorplugin.cpp
@@ -124,7 +124,7 @@ bool TextEditorPlugin::initialize(const QStringList &arguments, QString *errorMe
     // Make sure the shortcut still works when the completion widget is active
     completionShortcut->setContext(Qt::ApplicationShortcut);
     Core::Command *command = am->registerShortcut(completionShortcut, Constants::COMPLETE_THIS, context);
-#ifndef Q_OS_MAC
+#ifndef Q_WS_MAC
     command->setDefaultKeySequence(QKeySequence(tr("Ctrl+Space")));
 #else
     command->setDefaultKeySequence(QKeySequence(tr("Meta+Space")));
diff --git a/src/shared/help/bookmarkmanager.cpp b/src/shared/help/bookmarkmanager.cpp
index 7052495fcef9f6979accf102bc671a7699cf342e..96c8643765732bbb9de25b1bbbe1a0738315ce7b 100644
--- a/src/shared/help/bookmarkmanager.cpp
+++ b/src/shared/help/bookmarkmanager.cpp
@@ -436,9 +436,10 @@ void BookmarkWidget::setup(bool showButtons)
     treeView = new TreeView(this);
     vlayout->addWidget(treeView);
 
-    QString system = QLatin1String("win");
 #ifdef Q_OS_MAC
-    system = QLatin1String("mac");
+#   define SYSTEM "mac"
+#else
+#   define SYSTEM "win"
 #endif
 
     if (showButtons) {
@@ -449,8 +450,8 @@ void BookmarkWidget::setup(bool showButtons)
 
         addButton = new QToolButton(this);
         addButton->setText(tr("Add"));
-        addButton->setIcon(QIcon(QString::fromUtf8(
-            ":/trolltech/assistant/images/%1/addtab.png").arg(system)));
+        addButton->setIcon(QIcon(QString::fromLatin1(
+            ":/trolltech/assistant/images/" SYSTEM "/addtab.png")));
         addButton->setAutoRaise(true);
         addButton->setToolButtonStyle(Qt::ToolButtonTextBesideIcon);
         hlayout->addWidget(addButton);
@@ -458,8 +459,8 @@ void BookmarkWidget::setup(bool showButtons)
 
         removeButton = new QToolButton(this);
         removeButton->setText(tr("Remove"));
-        removeButton->setIcon(QIcon(QString::fromUtf8(
-            ":/trolltech/assistant/images/%1/closetab.png").arg(system)));
+        removeButton->setIcon(QIcon(QString::fromLatin1(
+            ":/trolltech/assistant/images/" SYSTEM "/closetab.png")));
         removeButton->setAutoRaise(true);
         removeButton->setToolButtonStyle(Qt::ToolButtonTextBesideIcon);
         hlayout->addWidget(removeButton);
diff --git a/src/shared/help/indexwindow.cpp b/src/shared/help/indexwindow.cpp
index 1b79ed00ae8aba6f78596baf543f551b9fdf48ae..8ae9f4e0a9346caf100e3af2059cbc6186c81cf1 100644
--- a/src/shared/help/indexwindow.cpp
+++ b/src/shared/help/indexwindow.cpp
@@ -140,7 +140,7 @@ bool IndexWindow::eventFilter(QObject *obj, QEvent *e)
             }
         }
     }
-#ifdef Q_OS_MAC
+#ifdef Q_WS_MAC
     else if (obj == m_indexWidget && e->type() == QEvent::KeyPress) {
         QKeyEvent *ke = static_cast<QKeyEvent*>(e);
         if (ke->key() == Qt::Key_Return || ke->key() == Qt::Key_Enter)
diff --git a/src/shared/proparser/profileevaluator.cpp b/src/shared/proparser/profileevaluator.cpp
index 0a352e2b0b2ca724b45a2173dd840bfb20980e61..6f6d6c7bbc36bcaa3b4cc9d5960e21ef8662409c 100644
--- a/src/shared/proparser/profileevaluator.cpp
+++ b/src/shared/proparser/profileevaluator.cpp
@@ -48,7 +48,7 @@
 #ifdef Q_OS_UNIX
 #include <unistd.h>
 #include <sys/utsname.h>
-#elif defined(Q_OS_WIN32)
+#else
 #include <Windows.h>
 #endif
 #include <stdio.h>
diff --git a/src/shared/qtlockedfile/qtlockedfile.h b/src/shared/qtlockedfile/qtlockedfile.h
index b4a5cbd06376a8c7d0526ebdf321a98b7ee001a1..49e26735dc67921a8014735e15775b4e4dbb3b7b 100644
--- a/src/shared/qtlockedfile/qtlockedfile.h
+++ b/src/shared/qtlockedfile/qtlockedfile.h
@@ -32,7 +32,7 @@
 
 #include <QtCore/QFile>
 
-#if defined(Q_WS_WIN)
+#if defined(Q_OS_WIN)
 #  if !defined(QT_QTLOCKEDFILE_EXPORT) && !defined(QT_QTLOCKEDFILE_IMPORT)
 #    define QT_QTLOCKEDFILE_EXPORT
 #  elif defined(QT_QTLOCKEDFILE_IMPORT)