diff --git a/src/libs/cplusplus/PPToken.cpp b/src/libs/cplusplus/PPToken.cpp
index 7b34c1ed35a..232569616db 100644
--- a/src/libs/cplusplus/PPToken.cpp
+++ b/src/libs/cplusplus/PPToken.cpp
@@ -32,6 +32,7 @@
 #include <cstring>
 
 using namespace CPlusPlus;
+using namespace CPlusPlus::Internal;
 
 bool ByteArrayRef::startsWith(const char *s) const
 {
@@ -52,7 +53,7 @@ int ByteArrayRef::count(char ch) const
     return num;
 }
 
-void Internal::PPToken::squeezeSource()
+void PPToken::squeezeSource()
 {
     if (hasSource()) {
         m_src = m_src.mid(offset, f.length);
diff --git a/src/plugins/cppeditor/cppelementevaluator.cpp b/src/plugins/cppeditor/cppelementevaluator.cpp
index 0da38d6958a..09fbd8a875b 100644
--- a/src/plugins/cppeditor/cppelementevaluator.cpp
+++ b/src/plugins/cppeditor/cppelementevaluator.cpp
@@ -42,7 +42,7 @@
 #include <QQueue>
 
 using namespace CppEditor;
-using namespace Internal;
+using namespace CppEditor::Internal;
 using namespace CPlusPlus;
 
 namespace {
diff --git a/src/plugins/cppeditor/cppincludehierarchy.cpp b/src/plugins/cppeditor/cppincludehierarchy.cpp
index e32467d2380..1af8f2595a0 100644
--- a/src/plugins/cppeditor/cppincludehierarchy.cpp
+++ b/src/plugins/cppeditor/cppincludehierarchy.cpp
@@ -50,7 +50,7 @@
 #include <QVBoxLayout>
 
 using namespace CppEditor;
-using namespace Internal;
+using namespace CppEditor::Internal;
 using namespace Utils;
 
 namespace CppEditor {
diff --git a/src/plugins/cppeditor/cppsnippetprovider.cpp b/src/plugins/cppeditor/cppsnippetprovider.cpp
index 4da115396ff..88f2f28750d 100644
--- a/src/plugins/cppeditor/cppsnippetprovider.cpp
+++ b/src/plugins/cppeditor/cppsnippetprovider.cpp
@@ -42,7 +42,7 @@
 #include <QCoreApplication>
 
 using namespace CppEditor;
-using namespace Internal;
+using namespace CppEditor::Internal;
 
 CppSnippetProvider::CppSnippetProvider() :
     TextEditor::ISnippetProvider()
diff --git a/src/plugins/cppeditor/cpptypehierarchy.cpp b/src/plugins/cppeditor/cpptypehierarchy.cpp
index 74271141062..b04808d678c 100644
--- a/src/plugins/cppeditor/cpptypehierarchy.cpp
+++ b/src/plugins/cppeditor/cpptypehierarchy.cpp
@@ -44,7 +44,7 @@
 #include <QLabel>
 
 using namespace CppEditor;
-using namespace Internal;
+using namespace CppEditor::Internal;
 using namespace Utils;
 
 namespace {