diff --git a/include/boost/intrusive/pointer_plus_bit.hpp b/include/boost/intrusive/pointer_plus_bit.hpp
index 35542b2..02290e6 100644
--- a/include/boost/intrusive/pointer_plus_bit.hpp
+++ b/include/boost/intrusive/pointer_plus_bit.hpp
@@ -54,7 +54,7 @@ struct pointer_plus_bit<T*>
    typedef T*        pointer;
 
    static pointer get_pointer(pointer n)
-   {  return pointer(std::size_t(n) & std::size_t(~1u));  }
+   {  return pointer(std::size_t(n) & ~std::size_t(1u));  }
 
    static void set_pointer(pointer &n, pointer p)
    {