diff --git a/arch/PKGBUILD b/arch/PKGBUILD
index 93ca5e3..c625277 100644
--- a/arch/PKGBUILD
+++ b/arch/PKGBUILD
@@ -71,7 +71,7 @@ package_libnetctlgui() {
 
 package_netctlgui-helper() {
   pkgdesc="Helper daemon for netctl-gui. A part of netctl-gui"
-  depends=('libnetctlgui')
+  depends=("libnetctlgui=${pkgver}")
   provides=('netctlgui-helper-qt4')
   conflicts=('netctlgui-helper-qt4')
   backup=('etc/netctl-gui.conf'
@@ -85,7 +85,7 @@ package_netctlgui-helper() {
 
 package_netctl-gui() {
   pkgdesc="Qt5 graphical front-end for netctl. A part of netctl-gui"
-  depends=('libnetctlgui' 'xdg-utils')
+  depends=("libnetctlgui=${pkgver}" 'xdg-utils')
   optdepends=('plasma-netctl-gui: KF5 widget'
               'netctlgui-helper: DBus helper daemon')
   provides=('netctl-gui-qt4')
diff --git a/arch/PKGBUILD-qt4 b/arch/PKGBUILD-qt4
index 5e0e46d..e7aa036 100644
--- a/arch/PKGBUILD-qt4
+++ b/arch/PKGBUILD-qt4
@@ -73,7 +73,7 @@ package_libnetctlgui-qt4() {
 
 package_netctlgui-helper-qt4() {
   pkgdesc="Helper daemon for netctl-gui. A part of netctl-gui"
-  depends=('libnetctlgui-qt4')
+  depends=("libnetctlgui-qt4=${pkgver}")
   provides=('netctlgui-helper')
   conflicts=('netctlgui-helper')
   backup=('etc/netctl-gui.conf'
@@ -87,7 +87,7 @@ package_netctlgui-helper-qt4() {
 
 package_netctl-gui-qt4() {
   pkgdesc="Qt4 graphical front-end for netctl. A part of netctl-gui"
-  depends=('libnetctlgui-qt4')
+  depends=("libnetctlgui-qt4=${pkgver}")
   optdepends=('kdeplasma-applets-netctl-gui: KDE widget'
               'netctlgui-helper-qt4: DBus helper daemon')
   provides=('netctl-gui')
diff --git a/sources/CMakeLists.txt b/sources/CMakeLists.txt
index 65088fa..5db99cd 100644
--- a/sources/CMakeLists.txt
+++ b/sources/CMakeLists.txt
@@ -55,6 +55,8 @@ if (CMAKE_COMPILER_IS_GNUCXX)
   set (CMAKE_CXX_FLAGS "-Wall -std=c++11")
   set (CMAKE_CXX_FLAGS_DEBUG "-g -O0")
   set (CMAKE_CXX_FLAGS_RELEASE "-O2 -DNDEBUG")
+  # avoid newer gcc warnings
+  add_definitions (-D_DEFAULT_SOURCE)
 else ()
   message (STATUS "Unknown compiler")
 endif ()
diff --git a/sources/gui/src/settingswindow.cpp b/sources/gui/src/settingswindow.cpp
index b114c0d..18b1310 100644
--- a/sources/gui/src/settingswindow.cpp
+++ b/sources/gui/src/settingswindow.cpp
@@ -114,7 +114,7 @@ void SettingsWindow::closeWindow()
 
     saveSettings();
     close();
-    ((MainWindow *)parent())->updateConfiguration();
+    dynamic_cast<MainWindow *>(parent())->updateConfiguration();
 }
 
 
@@ -467,7 +467,7 @@ void SettingsWindow::startHelper()
 {
     if (debug) qDebug() << PDEBUG;
 
-    ((MainWindow *)parent())->startHelper();
+    dynamic_cast<MainWindow *>(parent())->startHelper();
     updateHelper();
 }
 
@@ -476,12 +476,12 @@ void SettingsWindow::updateHelper()
 {
     if (debug) qDebug() << PDEBUG;
 
-    if (((MainWindow *)parent())->isHelperServiceActive()) {
+    if (dynamic_cast<MainWindow *>(parent())->isHelperServiceActive()) {
         ui->label_status->setText(QApplication::translate("SettingsWindow", "Active (systemd)"));
         ui->pushButton_status->setText(QApplication::translate("SettingsWindow", "Stop"));
         ui->pushButton_status->setIcon(QIcon::fromTheme("process-stop"));
         ui->pushButton_status->setDisabled(true);
-    } else if (((MainWindow *)parent())->isHelperActive()) {
+    } else if (dynamic_cast<MainWindow *>(parent())->isHelperActive()) {
         ui->label_status->setText(QApplication::translate("SettingsWindow", "Active"));
         ui->pushButton_status->setText(QApplication::translate("SettingsWindow", "Stop"));
         ui->pushButton_status->setIcon(QIcon::fromTheme("process-stop"));
diff --git a/sources/gui/src/trayicon.cpp b/sources/gui/src/trayicon.cpp
index da2bbbd..b3b9bee 100644
--- a/sources/gui/src/trayicon.cpp
+++ b/sources/gui/src/trayicon.cpp
@@ -30,7 +30,7 @@ TrayIcon::TrayIcon(QObject *parent, const bool debugCmd)
     : QSystemTrayIcon(parent),
       debug(debugCmd)
 {
-    mainWindow = (MainWindow *)parent;
+    mainWindow = dynamic_cast<MainWindow *>(parent);
 
     init();
 }
diff --git a/sources/plasmoid-kde4/netctl.h b/sources/plasmoid-kde4/netctl.h
index 3374b7c..9f6c048 100644
--- a/sources/plasmoid-kde4/netctl.h
+++ b/sources/plasmoid-kde4/netctl.h
@@ -98,22 +98,22 @@ protected:
 
 private:
     // ui
-    QWidget *graphicsWidget;
-    QHBoxLayout *layout;
-    IconLabel *iconLabel;
-    QLabel *textLabel;
+    QWidget *graphicsWidget = nullptr;
+    QHBoxLayout *layout = nullptr;
+    IconLabel *iconLabel = nullptr;
+    QLabel *textLabel = nullptr;
     // information
-    bool status;
+    bool status = false;
     QMap<QString, QString> info;
     QStringList profileList;
     // context menu
     void createActions();
     QList<QAction*> menuActions;
-    QMenu *startProfileMenu;
-    QMenu *switchToProfileMenu;
+    QMenu *startProfileMenu = nullptr;
+    QMenu *switchToProfileMenu = nullptr;
     QMap<QString, QAction*> contextMenu;
     // data engine
-    Plasma::DataEngine *netctlEngine;
+    Plasma::DataEngine *netctlEngine = nullptr;
     void connectToEngine();
     void disconnectFromEngine();
     QList<QVariant> sendDBusRequest(const QString cmd, const QList<QVariant> args = QList<QVariant>());
@@ -123,13 +123,15 @@ private:
     Ui::ConfigWindow uiWidConfig;
     Ui::About uiAboutConfig;
     // configuration
-    int autoUpdateInterval;
-    bool bigInterface;
-    bool debug;
-    QString textPattern;
+    int autoUpdateInterval = 1000;
+    bool bigInterface = true;
+    bool debug = false;
+    QString textPattern = QString();
     QStringList formatLine;
     QMap<QString, QString> paths;
-    bool useHelper, useSudo, useWifi;
+    bool useHelper = true;
+    bool useSudo = false;
+    bool useWifi = false;
 };
 
 K_EXPORT_PLASMA_APPLET(netctl, Netctl)