Add impl of member function swap()

include/boost/unordered/concurrent_flat_map.hpp

@@ -694,6 +694,13 @@ namespace boost {
         return table_.erase_if(f);
       }
 
+      void swap(concurrent_flat_map& other) noexcept(
+        boost::allocator_is_always_equal<Allocator>::type::value ||
+        boost::allocator_propagate_on_container_swap<Allocator>::type::value)
+      {
+        return table_.swap(other.table_);
+      }
+
       void clear() noexcept { table_.clear(); }
 
       /// Hash Policy

include/boost/unordered/detail/foa/core.hpp

@@ -1447,8 +1447,8 @@ public:
     swap(h(),x.h());
     swap(pred(),x.pred());
     swap(arrays,x.arrays);
-    swap(ml,x.ml);
-    swap(size_,x.size_);
+    swap_size_impl(ml,x.ml);
+    swap_size_impl(size_,x.size_);
   }
 
   void clear()noexcept