diff --git a/src/devices/nm-acd-manager.h b/src/devices/nm-acd-manager.h
index 758848460a..8376ba48e3 100644
--- a/src/devices/nm-acd-manager.h
+++ b/src/devices/nm-acd-manager.h
@@ -40,4 +40,7 @@ gboolean nm_acd_manager_start_probe (NMAcdManager *self, guint timeout);
 gboolean nm_acd_manager_check_address (NMAcdManager *self, in_addr_t address);
 void nm_acd_manager_announce_addresses (NMAcdManager *self);
 
+NM_AUTO_DEFINE_FCN0 (NMAcdManager *, _nm_auto_free_acdmgr, nm_acd_manager_free);
+#define nm_auto_free_acdmgr nm_auto (_nm_auto_free_acdmgr)
+
 #endif /* __NM_ACD_MANAGER__ */