diff --git a/include/libtorrent/intrusive_ptr_base.hpp b/include/libtorrent/intrusive_ptr_base.hpp
index c7fbe46ad..98a1fed2e 100644
--- a/include/libtorrent/intrusive_ptr_base.hpp
+++ b/include/libtorrent/intrusive_ptr_base.hpp
@@ -45,7 +45,8 @@ namespace libtorrent
 		intrusive_ptr_base(intrusive_ptr_base<T> const&)
 			: m_refs(0) {}
 
-		intrusive_ptr_base& operator=(intrusive_ptr_base const& rhs) {}
+		intrusive_ptr_base& operator=(intrusive_ptr_base const& rhs)
+		{ return *this; }
 
 		friend void intrusive_ptr_add_ref(intrusive_ptr_base<T> const* s)
 		{