(gdb) thread apply all bt

Thread 21 (Thread 0x7fffcd1b0830 (LWP 18282)):
#0  0x00007fffef6b6103 in poll () from /lib/libc.so.6
#1  0x00007ffff7a98b02 in ARDOUR::Session::midi_thread_work (this=0x1cec1a0) at libs/ardour/session_midi.cc:1220
#2  0x00007ffff7a985ea in ARDOUR::Session::_midi_thread_work (arg=0x1cec1a0) at libs/ardour/session_midi.cc:1138
#3  0x00007ffff2ea78ba in start_thread () from /lib/libpthread.so.0
#4  0x00007fffef6c101d in clone () from /lib/libc.so.6
#5  0x0000000000000000 in ?? ()

Thread 20 (Thread 0x7fffcd22b830 (LWP 18281)):
#0  0x00007fffef6b6103 in poll () from /lib/libc.so.6
#1  0x00007ffff7a35155 in ARDOUR::Session::butler_thread_work (this=0x1cec1a0) at libs/ardour/session_butler.cc:179
#2  0x00007ffff7a350d9 in ARDOUR::Session::_butler_thread_work (arg=0x1cec1a0) at libs/ardour/session_butler.cc:159
#3  0x00007ffff2ea78ba in start_thread () from /lib/libpthread.so.0
#4  0x00007fffef6c101d in clone () from /lib/libc.so.6
#5  0x0000000000000000 in ?? ()

Thread 19 (Thread 0x7fffcd4d8830 (LWP 18280)):
#0  0x00007ffff2eaf7dd in nanosleep () from /lib/libpthread.so.0
#1  0x00007ffff5a032a8 in g_usleep () from /lib/libglib-2.0.so.0
#2  0x00007ffff577b41c in Glib::usleep (microseconds=10000) at libs/glibmm2/glibmm/timer.cc:68
#3  0x00007ffff78fd962 in ARDOUR::AudioEngine::meter_thread (this=0x1a27be0) at libs/ardour/audioengine.cc:472
#4  0x00007ffff7905ddd in sigc::bound_mem_functor0<void, ARDOUR::AudioEngine>::operator() (this=0x1cebe28)
---Type <return> to continue, or q <return> to quit---
    at libs/sigc++2/sigc++/functors/mem_fun.h:1787
#5  0x00007ffff7905b54 in sigc::adaptor_functor<sigc::bound_mem_functor0<void, ARDOUR::AudioEngine> >::operator() (
    this=0x1cebe20) at libs/sigc++2/sigc++/adaptors/adaptor_trait.h:251
#6  0x00007ffff790552f in sigc::internal::slot_call0<sigc::bound_mem_functor0<void, ARDOUR::AudioEngine>, void>::call_it
    (rep=0x1cebdf0) at libs/sigc++2/sigc++/functors/slot.h:103
#7  0x0000000000818ac2 in sigc::slot0<void>::operator() (this=0x1bc8710) at libs/sigc++2/sigc++/functors/slot.h:440
#8  0x00007ffff5760a7c in call_thread_entry_slot (data=0x1bc8710) at libs/glibmm2/glibmm/thread.cc:43
#9  0x00007ffff5a006e4 in ?? () from /lib/libglib-2.0.so.0
#10 0x00007ffff2ea78ba in start_thread () from /lib/libpthread.so.0
#11 0x00007fffef6c101d in clone () from /lib/libc.so.6
#12 0x0000000000000000 in ?? ()

Thread 18 (Thread 0x7fffcd5c3710 (LWP 18279)):
#0  0x00007fffef67081f in memset () from /lib/libc.so.6
#1  0x00007fffebbd9031 in ?? () from /usr/lib/libvorbis.so.0
#2  0x00007fffebbda343 in _vp_psy_init () from /usr/lib/libvorbis.so.0
#3  0x00007fffebbd4cc5 in ?? () from /usr/lib/libvorbis.so.0
#4  0x00007fffebbd4db3 in vorbis_analysis_init () from /usr/lib/libvorbis.so.0
#5  0x00007ffff1711de2 in ?? () from /usr/lib/libsndfile.so.1
#6  0x00007ffff17000a6 in sf_writef_float () from /usr/lib/libsndfile.so.1
#7  0x00007ffff7a91a03 in ARDOUR::AudioExportSpecification::process (this=0x1e52028, nframes=1024)
    at libs/ardour/session_export.cc:418
#8  0x00007ffff7a9261d in ARDOUR::Session::process_export (this=0x1cec1a0, nframes=1024, spec=0x1e52028)
---Type <return> to continue, or q <return> to quit---
    at libs/ardour/session_export.cc:643
#9  0x00007ffff7a93e0a in sigc::bound_mem_functor2<int, ARDOUR::Session, unsigned int, ARDOUR::AudioExportSpecification*>::operator() (this=0x1a12500, _A_a1=@0x7fffcd548b34, _A_a2=@0x1a12520) at libs/sigc++2/sigc++/functors/mem_fun.h:1917
#10 0x00007ffff7a93c5d in sigc::adaptor_functor<sigc::bound_mem_functor2<int, ARDOUR::Session, unsigned int, ARDOUR::AudioExportSpecification*> >::operator()<unsigned int const&, ARDOUR::AudioExportSpecification*&> (this=0x1a124f8, 
    _A_arg1=@0x7fffcd548b34, _A_arg2=@0x1a12520) at libs/sigc++2/sigc++/adaptors/adaptor_trait.h:103
#11 0x00007ffff7a93a9a in sigc::bind_functor<-1, sigc::bound_mem_functor2<int, ARDOUR::Session, unsigned int, ARDOUR::AudioExportSpecification*>, ARDOUR::AudioExportSpecification*, sigc::nil, sigc::nil, sigc::nil, sigc::nil, sigc::nil, sigc::nil>::operator()<unsigned int const&> (this=0x1a124f0, _A_arg1=@0x7fffcd548b34) at libs/sigc++2/sigc++/adaptors/bind.h:1122
#12 0x00007ffff7a937f6 in sigc::internal::slot_call1<sigc::bind_functor<-1, sigc::bound_mem_functor2<int, ARDOUR::Session, unsigned int, ARDOUR::AudioExportSpecification*>, ARDOUR::AudioExportSpecification*, sigc::nil, sigc::nil, sigc::nil, sigc::nil, sigc::nil, sigc::nil>, int, unsigned int>::call_it (rep=0x1a124c0, a_1=@0x7fffcd548b34)
    at libs/sigc++2/sigc++/functors/slot.h:137
#13 0x00007ffff79045c0 in sigc::internal::signal_emit1<int, unsigned int, sigc::nil>::emit (impl=0x2141dd0, 
    _A_a1=@0x7fffcd548b34) at libs/sigc++2/sigc++/signal.h:917
#14 0x00007ffff79029f5 in sigc::signal1<int, unsigned int, sigc::nil>::emit (this=0x1a27bf0, _A_a1=@0x7fffcd548b34)
    at libs/sigc++2/sigc++/signal.h:2773
#15 0x00007ffff7901bb3 in sigc::signal1<int, unsigned int, sigc::nil>::operator() (this=0x1a27bf0, _A_a1=@0x7fffcd548b34)
    at libs/sigc++2/sigc++/signal.h:2781
#16 0x00007ffff78fd1db in ARDOUR::AudioEngine::process_callback (this=0x1a27be0, nframes=1024)
    at libs/ardour/audioengine.cc:336
#17 0x00007ffff78fd006 in ARDOUR::AudioEngine::_process_callback (nframes=1024, arg=0x1a27be0)
    at libs/ardour/audioengine.cc:289
---Type <return> to continue, or q <return> to quit---
#18 0x00007ffff30c70f0 in jack_client_thread_aux (arg=0x1a2c4c0) at client.c:1965
#19 0x00007ffff30c7222 in jack_client_thread (arg=0x1a2c4c0) at client.c:2006
#20 0x00007ffff30cc4a4 in jack_thread_proxy (varg=0x1ce9610) at thread.c:125
#21 0x00007ffff2ea78ba in start_thread () from /lib/libpthread.so.0
#22 0x00007fffef6c101d in clone () from /lib/libc.so.6
#23 0x0000000000000000 in ?? ()

Thread 17 (Thread 0x7fffcf5cb710 (LWP 18276)):
#0  0x00007ffff2eac16c in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#1  0x00007ffff30c8de9 in mb_thread_func (arg=0x0) at messagebuffer.c:72
#2  0x00007ffff2ea78ba in start_thread () from /lib/libpthread.so.0
#3  0x00007fffef6c101d in clone () from /lib/libc.so.6
#4  0x0000000000000000 in ?? ()

Thread 4 (Thread 0x7fffe61df710 (LWP 18261)):
#0  0x00007ffff2eac16c in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#1  0x00007ffff5761521 in Glib::Cond::wait (this=0x1362120, mutex=...) at libs/glibmm2/glibmm/thread.cc:362
#2  0x00007ffff78dc0e6 in ARDOUR::Analyser::work () at libs/ardour/analyser.cc:85
#3  0x00007ffff78dbd8d in analyser_work () at libs/ardour/analyser.cc:49
#4  0x0000000000bccf67 in sigc::pointer_functor0<void>::operator()() const ()
#5  0x0000000000bcc2f4 in sigc::adaptor_functor<sigc::pointer_functor0<void> >::operator()() const ()
#6  0x0000000000bcaca3 in sigc::internal::slot_call0<sigc::pointer_functor0<void>, void>::call_it(sigc::internal::slot_rep*) ()
---Type <return> to continue, or q <return> to quit---
#7  0x0000000000818ac2 in sigc::slot0<void>::operator() (this=0x1362140) at libs/sigc++2/sigc++/functors/slot.h:440
#8  0x00007ffff5760a7c in call_thread_entry_slot (data=0x1362140) at libs/glibmm2/glibmm/thread.cc:43
#9  0x00007ffff5a006e4 in ?? () from /lib/libglib-2.0.so.0
#10 0x00007ffff2ea78ba in start_thread () from /lib/libpthread.so.0
#11 0x00007fffef6c101d in clone () from /lib/libc.so.6
#12 0x0000000000000000 in ?? ()

Thread 3 (Thread 0x7fffe69e0710 (LWP 18260)):
#0  0x00007ffff2eac16c in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#1  0x00007ffff5761521 in Glib::Cond::wait (this=0x13549f0, mutex=...) at libs/glibmm2/glibmm/thread.cc:362
#2  0x00007ffff7ad41ea in peak_thread_work () at libs/ardour/source_factory.cc:65
#3  0x0000000000bccf67 in sigc::pointer_functor0<void>::operator()() const ()
#4  0x0000000000bcc2f4 in sigc::adaptor_functor<sigc::pointer_functor0<void> >::operator()() const ()
#5  0x0000000000bcaca3 in sigc::internal::slot_call0<sigc::pointer_functor0<void>, void>::call_it(sigc::internal::slot_rep*) ()
#6  0x0000000000818ac2 in sigc::slot0<void>::operator() (this=0x1354e60) at libs/sigc++2/sigc++/functors/slot.h:440
#7  0x00007ffff5760a7c in call_thread_entry_slot (data=0x1354e60) at libs/glibmm2/glibmm/thread.cc:43
#8  0x00007ffff5a006e4 in ?? () from /lib/libglib-2.0.so.0
#9  0x00007ffff2ea78ba in start_thread () from /lib/libpthread.so.0
#10 0x00007fffef6c101d in clone () from /lib/libc.so.6
#11 0x0000000000000000 in ?? ()

Thread 2 (Thread 0x7fffe71e1710 (LWP 18259)):
---Type <return> to continue, or q <return> to quit---
#0  0x00007ffff2eac16c in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#1  0x00007ffff5761521 in Glib::Cond::wait (this=0x13549f0, mutex=...) at libs/glibmm2/glibmm/thread.cc:362
#2  0x00007ffff7ad41ea in peak_thread_work () at libs/ardour/source_factory.cc:65
#3  0x0000000000bccf67 in sigc::pointer_functor0<void>::operator()() const ()
#4  0x0000000000bcc2f4 in sigc::adaptor_functor<sigc::pointer_functor0<void> >::operator()() const ()
#5  0x0000000000bcaca3 in sigc::internal::slot_call0<sigc::pointer_functor0<void>, void>::call_it(sigc::internal::slot_rep*) ()
#6  0x0000000000818ac2 in sigc::slot0<void>::operator() (this=0x1354a10) at libs/sigc++2/sigc++/functors/slot.h:440
#7  0x00007ffff5760a7c in call_thread_entry_slot (data=0x1354a10) at libs/glibmm2/glibmm/thread.cc:43
#8  0x00007ffff5a006e4 in ?? () from /lib/libglib-2.0.so.0
#9  0x00007ffff2ea78ba in start_thread () from /lib/libpthread.so.0
#10 0x00007fffef6c101d in clone () from /lib/libc.so.6
#11 0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7ffff7fae7e0 (LWP 18256)):
#0  0x00007ffff2eaf0bd in read () from /lib/libpthread.so.0
#1  0x00007ffff30c3caf in oop_client_deliver_request (ptr=0x1a2c4c0, req=0x7fffffffb800) at client.c:253
#2  0x00007ffff30c3d91 in jack_client_deliver_request (client=0x1a2c4c0, req=0x7fffffffb800) at client.c:284
#3  0x00007ffff30c5eac in jack_set_freewheel (client=0x1a2c4c0, onoff=1) at client.c:1338
#4  0x00007ffff78ffccf in ARDOUR::AudioEngine::freewheel (this=0x1a27be0, onoff=true) at libs/ardour/audioengine.cc:1065
#5  0x00007ffff7a91d1e in ARDOUR::Session::start_audio_export (this=0x1cec1a0, spec=...)
    at libs/ardour/session_export.cc:449
#6  0x0000000000a99e04 in ExportSessionDialog::export_audio_data (this=0x1e52000)
---Type <return> to continue, or q <return> to quit---
    at gtk2_ardour/export_session_dialog.cc:35
#7  0x0000000000a8d799 in ExportDialog::do_export (this=0x1e52000) at gtk2_ardour/export_dialog.cc:1101
#8  0x0000000000a95b17 in sigc::bound_mem_functor0<void, ExportDialog>::operator()() const ()
#9  0x0000000000a95296 in sigc::adaptor_functor<sigc::bound_mem_functor0<void, ExportDialog> >::operator()() const ()
#10 0x0000000000a93fef in sigc::internal::slot_call0<sigc::bound_mem_functor0<void, ExportDialog>, void>::call_it (
    rep=0x1e79100) at libs/sigc++2/sigc++/functors/slot.h:103
#11 0x0000000000818ac2 in sigc::slot0<void>::operator() (this=0x1e790d8) at libs/sigc++2/sigc++/functors/slot.h:440
#12 0x00007ffff57609f5 in Glib::SignalProxyNormal::slot0_void_callback (self=0x1e65c80, data=0x1e790d0)
    at libs/glibmm2/glibmm/signalproxy.cc:95
#13 0x00007ffff629147e in g_closure_invoke () from /usr/lib/libgobject-2.0.so.0
#14 0x00007ffff62a77f4 in ?? () from /usr/lib/libgobject-2.0.so.0
#15 0x00007ffff62a8a76 in g_signal_emit_valist () from /usr/lib/libgobject-2.0.so.0
#16 0x00007ffff62a8fc3 in g_signal_emit () from /usr/lib/libgobject-2.0.so.0
#17 0x00007ffff5192235 in ?? () from /usr/lib/libgtk-x11-2.0.so.0
#18 0x00007ffff629147e in g_closure_invoke () from /usr/lib/libgobject-2.0.so.0
#19 0x00007ffff62a6cc1 in ?? () from /usr/lib/libgobject-2.0.so.0
#20 0x00007ffff62a8a76 in g_signal_emit_valist () from /usr/lib/libgobject-2.0.so.0
#21 0x00007ffff62a8fc3 in g_signal_emit () from /usr/lib/libgobject-2.0.so.0
#22 0x00007ffff5190f3d in ?? () from /usr/lib/libgtk-x11-2.0.so.0
#23 0x00007ffff523dc08 in ?? () from /usr/lib/libgtk-x11-2.0.so.0
#24 0x00007ffff629147e in g_closure_invoke () from /usr/lib/libgobject-2.0.so.0
#25 0x00007ffff62a7040 in ?? () from /usr/lib/libgobject-2.0.so.0
#26 0x00007ffff62a88bd in g_signal_emit_valist () from /usr/lib/libgobject-2.0.so.0
---Type <return> to continue, or q <return> to quit---
#27 0x00007ffff62a8fc3 in g_signal_emit () from /usr/lib/libgobject-2.0.so.0
#28 0x00007ffff5353f6f in ?? () from /usr/lib/libgtk-x11-2.0.so.0
#29 0x00007ffff52360f3 in gtk_propagate_event () from /usr/lib/libgtk-x11-2.0.so.0
#30 0x00007ffff52371ab in gtk_main_do_event () from /usr/lib/libgtk-x11-2.0.so.0
#31 0x00007ffff4eab3bc in ?? () from /usr/lib/libgdk-x11-2.0.so.0
#32 0x00007ffff59d76c2 in g_main_context_dispatch () from /lib/libglib-2.0.so.0
#33 0x00007ffff59db538 in ?? () from /lib/libglib-2.0.so.0
#34 0x00007ffff59dba45 in g_main_loop_run () from /lib/libglib-2.0.so.0
#35 0x00007ffff5237647 in gtk_main () from /usr/lib/libgtk-x11-2.0.so.0
#36 0x00007ffff38f6437 in Gtk::Main::run_impl (this=0x10f8470) at libs/gtkmm2/gtk/gtkmm/main.cc:503
#37 0x00007ffff38f6229 in Gtk::Main::run () at libs/gtkmm2/gtk/gtkmm/main.cc:450
#38 0x00007ffff338d9ee in Gtkmm2ext::UI::run (this=0x10f2b80, old_receiver=...) at libs/gtkmm2ext/gtk_ui.cc:230
#39 0x0000000000b15617 in main (argc=1, argv=0x7fffffffe098) at gtk2_ardour/main.cc:398