diff -up ./src/polkitagent/polkitagentlistener.c.ori ./src/polkitagent/polkitagentlistener.c

--- ./src/polkitagent/polkitagentlistener.c.ori	2018-08-10 14:58:58.555475169 +0200

+++ ./src/polkitagent/polkitagentlistener.c	2018-08-10 14:59:15.900396570 +0200

@@ -439,6 +439,7 @@ polkit_agent_listener_register_with_opti

           server->thread_initialization_error = NULL;

           g_thread_join (server->thread);

           server_free (server);

+          server = NULL;

           goto out;

         }

     }