diff --git a/src/corelib/tools/qset.h b/src/corelib/tools/qset.h
index d8d6e39dfbd..4cb0bcdd975 100644
--- a/src/corelib/tools/qset.h
+++ b/src/corelib/tools/qset.h
@@ -207,7 +207,7 @@ public:
 
     friend QSet operator+(const QSet &lhs, const QSet &rhs) { return QSet(lhs) += rhs; }
     friend QSet operator+(QSet &&lhs, const QSet &rhs) { lhs += rhs; return std::move(lhs); }
-    friend QSet operator+(const QSet &lhs, QSet &&rhs) { return lhs += std::move(rhs); }
+    friend QSet operator+(const QSet &lhs, QSet &&rhs) { return QSet(lhs) += std::move(rhs); }
     friend QSet operator+(QSet &&lhs, QSet &&rhs) { return std::move(lhs) += std::move(rhs); }
 
     friend QSet operator-(const QSet &lhs, const QSet &rhs) { return QSet(lhs) -= rhs; }