I'm getting this when connecting Gabble master with GLib master.
Maybe a GLib regression, I'll investigate.

(telepathy-gabble:7968): wocky-WARNING **: The underlying stream 'GSocketOutputStream' used by the WockyTLSSession called the GAsyncResultCallback recursively.  This is an error in the underlying implementation: in some cases it may lead to unbounded recursion.  Result callbacks should always be dispatched from the mainloop.


#0  0x00007ffff67d2070 in g_logv (log_domain=0x7ffff7bdb399 "wocky", log_level=G_LOG_LEVEL_WARNING, 
    format=0x7ffff7bdbc40 "The underlying stream '%s' used by the WockyTLSSession called the GAsyncResultCallback recursively.  This is an error in the underlying implementation: in some cases it may lead to unbounded recursion"..., args1=0x7fffffffd368) at gmessages.c:758
#1  0x00007ffff67d2164 in g_log (log_domain=0x7ffff7bdb399 "wocky", log_level=G_LOG_LEVEL_WARNING, 
    format=0x7ffff7bdbc40 "The underlying stream '%s' used by the WockyTLSSession called the GAsyncResultCallback recursively.  This is an error in the underlying implementation: in some cases it may lead to unbounded recursion"...) at gmessages.c:792
#2  0x00007ffff7bc7f09 in wocky_tls_session_push_func (user_data=0x767180, buffer=0xa495a0, count=118) at wocky-tls.c:1267
#3  0x0000003cb701d533 in _gnutls_writev_emu (giovec_cnt=<optimized out>, giovec=<optimized out>, session=<optimized out>)
    at gnutls_buffers.c:390
#4  _gnutls_writev (giovec_cnt=1, giovec=0x7fffffffd500, session=0x806860) at gnutls_buffers.c:417
#5  _gnutls_io_write_flush (session=0x806860) at gnutls_buffers.c:731
#6  0x0000003cb701d880 in _gnutls_handshake_io_write_flush (session=0x806860) at gnutls_buffers.c:809
#7  0x0000003cb701e663 in _gnutls_send_handshake (session=0x806860, bufel=0xa58830, type=GNUTLS_HANDSHAKE_CLIENT_HELLO)
    at gnutls_handshake.c:1228
#8  0x0000003cb702237b in _gnutls_send_client_hello (again=<optimized out>, session=0x806860) at gnutls_handshake.c:2215
#9  _gnutls_send_hello (session=0x806860, again=<optimized out>) at gnutls_handshake.c:2323
#10 0x0000003cb7022b4d in _gnutls_handshake_client (session=0x806860) at gnutls_handshake.c:2751
#11 0x0000003cb70230a5 in gnutls_handshake (session=0x806860) at gnutls_handshake.c:2673
#12 0x00007ffff7bc5e90 in wocky_tls_session_try_operation (session=0x767180, operation=WOCKY_TLS_OP_READ) at wocky-tls.c:396
#13 0x00007ffff7bc67f4 in wocky_tls_session_handshake_async (session=0x767180, io_priority=0, cancellable=0x7ffff0001270, 
    callback=0x7ffff7bbffb0 <session_handshake_cb>, user_data=0x7efc40) at wocky-tls.c:602
#14 0x00007ffff7bbfe8d in do_handshake (self=0x7efc40) at wocky-tls-connector.c:269
#15 0x00007ffff7bc06c3 in wocky_tls_connector_secure_async (self=0x7efc40, connection=0x7e9000, old_style_ssl=1, 
    peername=0x778960 "jabber.belnet.be", extra_identities=0x0, cancellable=0x7ffff0001270, 
    callback=0x7ffff7b9700c <tls_connector_secure_cb>, user_data=0x760ad0) at wocky-tls-connector.c:485
#16 0x00007ffff7b96802 in maybe_old_ssl (self=0x760ad0) at wocky-connector.c:1036
#17 0x00007ffff7b963d9 in tcp_host_connected (source=0x7d59e0, result=0x7e7e60, connector=0x760ad0) at wocky-connector.c:940
#18 0x00007ffff73df95d in g_simple_async_result_complete (simple=0x7e7e60) at gsimpleasyncresult.c:767
#19 0x00007ffff73e9393 in g_socket_client_async_connect_complete (data=0x7d5a30) at gsocketclient.c:1316
#20 0x00007ffff73e96f0 in g_socket_client_tls_handshake (data=0x7d5a30) at gsocketclient.c:1392
#21 0x00007ffff73e9983 in g_socket_client_connected_callback (source=0x7ef8a0, result=0x7ef910, user_data=0x7d5a30) at gsocketclient.c:1469
#22 0x00007ffff73df95d in g_simple_async_result_complete (simple=0x7ef910) at gsimpleasyncresult.c:767
#23 0x00007ffff73eaaf9 in g_socket_connection_connect_callback (socket=0x7dd190, condition=G_IO_OUT, user_data=0x7ef910)
    at gsocketconnection.c:242
#24 0x00007ffff73e5170 in socket_source_dispatch (source=0x7a1a50, callback=0x7ffff73eaa43 <g_socket_connection_connect_callback>, 
    user_data=0x7ef910) at gsocket.c:3168
#25 0x00007ffff67c851c in g_main_dispatch (context=0x753de0) at gmain.c:2539
#26 0x00007ffff67c91c1 in g_main_context_dispatch (context=0x753de0) at gmain.c:3075
#27 0x00007ffff67c93a4 in g_main_context_iterate (context=0x753de0, block=1, dispatch=1, self=0x74d780) at gmain.c:3146
---Type <return> to continue, or q <return> to quit---
#28 0x00007ffff67c97cd in g_main_loop_run (loop=0x758930) at gmain.c:3340
#29 0x00007ffff787adfe in tp_run_connection_manager (prog_name=0x4de849 "telepathy-gabble", version=0x4de83e "0.16.999.1", 
    construct_cm=0x4288ec <construct_cm>, argc=1, argv=0x7fffffffdf38) at run.c:285
#30 0x0000000000428c4a in gabble_main (argc=1, argv=0x7fffffffdf38) at gabble.c:182
#31 0x00000000004288e9 in main (argc=1, argv=0x7fffffffdf38) at main.c:33