diff --git a/libdevcore/CommonData.h b/libdevcore/CommonData.h
index 63a374c30..f587b3533 100644
--- a/libdevcore/CommonData.h
+++ b/libdevcore/CommonData.h
@@ -55,6 +55,13 @@ template <class T, class U> std::set<T>& operator+=(std::set<T>& _a, U const& _b
 	_a.insert(_b.begin(), _b.end());
 	return _a;
 }
+/// Concatenate the contents of a container onto a set, move variant.
+template <class T, class U> std::set<T>& operator+=(std::set<T>& _a, U&& _b)
+{
+	for (auto&& x: _b)
+		_a.insert(std::move(x));
+	return _a;
+}
 /// Concatenate two vectors of elements.
 template <class T>
 inline std::vector<T> operator+(std::vector<T> const& _a, std::vector<T> const& _b)