Method __do_complete

include/stdexec/__detail/__spawn.hpp:110–123

      __assoc_t __assoc_;

      static void __do_complete(__spawn_state_base* __base) noexcept
      {
        auto* __self = static_cast<__spawn_state*>(__base);

        [[maybe_unused]]
        auto __assoc = std::move(__self->__assoc_);

        {
          using __traits = std::allocator_traits<_Alloc>::template rebind_traits<__spawn_state>;
          typename __traits::allocator_type __alloc(std::move(__self->__alloc_));
          __traits::destroy(__alloc, __self);
          __traits::deallocate(__alloc, __self, 1);
        }
      }
    };

    struct spawn_t