diff --git a/src/plugins/coreplugin/editormanager/editormanager.cpp b/src/plugins/coreplugin/editormanager/editormanager.cpp
index fa7d79fecff..46323c474de 100644
--- a/src/plugins/coreplugin/editormanager/editormanager.cpp
+++ b/src/plugins/coreplugin/editormanager/editormanager.cpp
@@ -1417,6 +1417,7 @@ IEditor *EditorManager::createEditor(const Id &editorId, const QString &fileName
     }
 
     IEditor *editor = factories.front()->createEditor();
+    QTC_CHECK(!editor || editor->id().isValid()); // sanity check that the editor has an id set
     if (editor)
         connect(editor->document(), SIGNAL(changed()), m_instance, SLOT(handleDocumentStateChange()));
     if (editor)