diff --git a/src/plugins/qmldesigner/components/formeditor/resizecontroller.cpp b/src/plugins/qmldesigner/components/formeditor/resizecontroller.cpp
index 36b526f857967f1298f33b93a7b27c5627e98858..c60d0cf591825c9effccbf8d77f9533fd4bfff6e 100644
--- a/src/plugins/qmldesigner/components/formeditor/resizecontroller.cpp
+++ b/src/plugins/qmldesigner/components/formeditor/resizecontroller.cpp
@@ -164,7 +164,9 @@ ResizeController::~ResizeController()
 
 ResizeController &ResizeController::operator =(const ResizeController &other)
 {
-    m_data = other.m_data;
+    if (this != &other)
+        m_data = other.m_data;
+    return *this;
 }