diff --git a/src/plugins/cppeditor/cpppreprocessoradditionwidget.h b/src/plugins/cppeditor/cpppreprocessoradditionwidget.h
index c9289b0e21c..d69a3d9de30 100644
--- a/src/plugins/cppeditor/cpppreprocessoradditionwidget.h
+++ b/src/plugins/cppeditor/cpppreprocessoradditionwidget.h
@@ -37,12 +37,9 @@
 #include <QVariantMap>
 #include <QPointer>
 
-namespace Ui {
-class CppPreProcessorAdditionWidget;
-}
-
 namespace CppEditor {
 namespace Internal {
+namespace Ui { class CppPreProcessorAdditionWidget; }
 
 class PreProcessorAdditionWidget : public QWidget
 {
diff --git a/src/plugins/cppeditor/cpppreprocessoradditionwidget.ui b/src/plugins/cppeditor/cpppreprocessoradditionwidget.ui
index c009a50646a..101ba17d3fe 100644
--- a/src/plugins/cppeditor/cpppreprocessoradditionwidget.ui
+++ b/src/plugins/cppeditor/cpppreprocessoradditionwidget.ui
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <ui version="4.0">
- <class>CppPreProcessorAdditionWidget</class>
- <widget class="QWidget" name="CppPreProcessorAdditionWidget">
+ <class>CppEditor::Internal::CppPreProcessorAdditionWidget</class>
+ <widget class="QWidget" name="CppEditor::Internal::CppPreProcessorAdditionWidget">
   <property name="geometry">
    <rect>
     <x>0</x>