diff --git a/geometrytip.cpp b/geometrytip.cpp
index cf826e42bf..237f3644f3 100644
--- a/geometrytip.cpp
+++ b/geometrytip.cpp
@@ -40,6 +40,13 @@ GeometryTip::~GeometryTip()
 {
 }
 
+static QString numberWithSign(int n)
+{
+    const QLocale locale;
+    const QChar sign = n >= 0 ? locale.positiveSign() : locale.negativeSign();
+    return sign + QString::number(std::abs(n));
+}
+
 void GeometryTip::setGeometry(const QRect& geom)
 {
     int w = geom.width();
@@ -53,9 +60,11 @@ void GeometryTip::setGeometry(const QRect& geom)
     }
 
     h = qMax(h, 0);   // in case of isShade() and PBaseSize
-    QString pos;
-    pos.sprintf("%+d,%+d<br>(<b>%d&nbsp;x&nbsp;%d</b>)",
-                geom.x(), geom.y(), w, h);
+    const QString pos = QStringLiteral("%1,%2<br>(<b>%3&nbsp;x&nbsp;%4</b>)")
+        .arg(numberWithSign(geom.x()))
+        .arg(numberWithSign(geom.y()))
+        .arg(w)
+        .arg(h);
     setText(pos);
     adjustSize();
     move(geom.x() + ((geom.width()  - width())  / 2),
diff --git a/main_x11.cpp b/main_x11.cpp
index 721bdf76e6..891b8393a3 100644
--- a/main_x11.cpp
+++ b/main_x11.cpp
@@ -363,7 +363,6 @@ KWIN_EXPORT int kdemain(int argc, char * argv[])
         if ((pos = display_name.lastIndexOf('.')) != -1)
             display_name.remove(pos, 10);   // 10 is enough to be sure we removed ".s"
 
-        QString envir;
         for (int i = 0; i < number_of_screens; i++) {
             // If execution doesn't pass by here, then kwin
             // acts exactly as previously
@@ -382,7 +381,9 @@ KWIN_EXPORT int kdemain(int argc, char * argv[])
         }
         // In the next statement, display_name shouldn't contain a screen
         // number. If it had it, it was removed at the "pos" check
-        envir.sprintf("DISPLAY=%s.%d", display_name.data(), KWin::Application::x11ScreenNumber());
+        const QString envir = QStringLiteral("DISPLAY=%1.%2")
+            .arg(display_name.data())
+            .arg(KWin::Application::x11ScreenNumber());
 
         if (putenv(strdup(envir.toLatin1().constData()))) {
             fprintf(stderr, "%s: WARNING: unable to set DISPLAY environment variable\n", argv[0]);
diff --git a/virtualdesktops.cpp b/virtualdesktops.cpp
index 80ee4774c7..76ed4819fa 100644
--- a/virtualdesktops.cpp
+++ b/virtualdesktops.cpp
@@ -698,7 +698,7 @@ void VirtualDesktopManager::load()
     if (screen_number == 0) {
         groupname = QStringLiteral("Desktops");
     } else {
-        groupname.sprintf("Desktops-screen-%d", screen_number);
+        groupname = QStringLiteral("Desktops-screen-%1").arg(screen_number);
     }
     KConfigGroup group(m_config, groupname);
     const int n = group.readEntry("Number", 1);
@@ -752,7 +752,7 @@ void VirtualDesktopManager::save()
     if (screen_number == 0) {
         groupname = QStringLiteral("Desktops");
     } else {
-        groupname.sprintf("Desktops-screen-%d", screen_number);
+        groupname = QStringLiteral("Desktops-screen-%1").arg(screen_number);
     }
     KConfigGroup group(m_config, groupname);