diff --git a/src/widgets/widgets/qmdiarea.cpp b/src/widgets/widgets/qmdiarea.cpp
index 4bbb5c62549..3b4505688b6 100644
--- a/src/widgets/widgets/qmdiarea.cpp
+++ b/src/widgets/widgets/qmdiarea.cpp
@@ -220,19 +220,7 @@ static inline QMdiArea *mdiAreaParent(QWidget *widget)
 }
 
 #if QT_CONFIG(tabwidget)
-QTabBar::Shape _q_tb_tabBarShapeFrom(QTabWidget::TabShape shape, QTabWidget::TabPosition position)
-{
-    const bool rounded = (shape == QTabWidget::Rounded);
-    if (position == QTabWidget::North)
-        return rounded ? QTabBar::RoundedNorth : QTabBar::TriangularNorth;
-    if (position == QTabWidget::South)
-        return rounded ? QTabBar::RoundedSouth : QTabBar::TriangularSouth;
-    if (position == QTabWidget::East)
-        return rounded ? QTabBar::RoundedEast : QTabBar::TriangularEast;
-    if (position == QTabWidget::West)
-        return rounded ? QTabBar::RoundedWest : QTabBar::TriangularWest;
-    return QTabBar::RoundedNorth;
-}
+QTabBar::Shape _q_tb_tabBarShapeFrom(QTabWidget::TabShape shape, QTabWidget::TabPosition position);
 #endif // QT_CONFIG(tabwidget)
 
 static inline QString tabTextFor(QMdiSubWindow *subWindow)
diff --git a/src/widgets/widgets/qtabwidget.cpp b/src/widgets/widgets/qtabwidget.cpp
index 89e3d59a061..8db76db7c71 100644
--- a/src/widgets/widgets/qtabwidget.cpp
+++ b/src/widgets/widgets/qtabwidget.cpp
@@ -1407,6 +1407,20 @@ void QTabWidget::clear()
         removeTab(0);
 }
 
+QTabBar::Shape _q_tb_tabBarShapeFrom(QTabWidget::TabShape shape, QTabWidget::TabPosition position)
+{
+    const bool rounded = (shape == QTabWidget::Rounded);
+    if (position == QTabWidget::North)
+        return rounded ? QTabBar::RoundedNorth : QTabBar::TriangularNorth;
+    if (position == QTabWidget::South)
+        return rounded ? QTabBar::RoundedSouth : QTabBar::TriangularSouth;
+    if (position == QTabWidget::East)
+        return rounded ? QTabBar::RoundedEast : QTabBar::TriangularEast;
+    if (position == QTabWidget::West)
+        return rounded ? QTabBar::RoundedWest : QTabBar::TriangularWest;
+    return QTabBar::RoundedNorth;
+}
+
 QT_END_NAMESPACE
 
 #include "moc_qtabwidget.cpp"