diff --git boost/unordered/detail/table.hpp boost/unordered/detail/table.hpp
index a4c875c..9cfa3da 100644
--- boost/unordered/detail/table.hpp
+++ boost/unordered/detail/table.hpp
@@ -455,6 +455,7 @@ namespace boost { namespace unordered { namespace detail {
 
         void swap_allocators(table& other, false_type)
         {
+            (void)other;
             // According to 23.2.1.8, if propagate_on_container_swap is
             // false the behaviour is undefined unless the allocators
             // are equal.