#0  __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:49
#1  0x00007ffff35bf538 in __GI_abort () at abort.c:79
#2  0x00007ffff35bf421 in __assert_fail_base (fmt=0x7ffff3724e08 "%s%s%s:%u: %s%sAssertion `%s' failed.\n%n", assertion=0x7ffff7a15f33 "r", file=0x7ffff7a15f10 "../libs/ardour/midi_ring_buffer.cc", line=93, function=<optimized out>) at assert.c:92
#3  0x00007ffff35ceaa2 in __GI___assert_fail
    (assertion=0x7ffff7a15f33 "r", file=0x7ffff7a15f10 "../libs/ardour/midi_ring_buffer.cc", line=93, function=0x7ffff7a15e18 "size_t ARDOUR::MidiRingBuffer<T>::read(ARDOUR::MidiBuffer&, ARDOUR::samplepos_t, ARDOUR::samplepos_t, ARDOUR::samplecnt_t, bool) [with T = long int; size_t = long unsigned int; ARDOUR::samplepos_t = l"...) at assert.c:101
#4  0x00007ffff7508f53 in ARDOUR::MidiRingBuffer<long>::read(ARDOUR::MidiBuffer&, long, long, long, bool) (this=0x55556135b530, dst=..., start=0, end=1, offset=255, stop_on_overflow_in_dst=true) at ../libs/ardour/midi_ring_buffer.cc:93
#5  0x00007ffff7527840 in ARDOUR::MidiTrack::snapshot_out_of_band_data(long) (this=0x55556135a580, nframes=256) at ../libs/ardour/midi_track.cc:480
#6  0x00007ffff76741ff in ARDOUR::Route::run_route(long, long, unsigned int, bool, bool) (this=0x55556135a580, start_sample=16444105, end_sample=16444105, nframes=256, gain_automation_ok=false, run_disk_reader=false) at ../libs/ardour/route.cc:709
#7  0x00007ffff7688547 in ARDOUR::Route::no_roll_unlocked(unsigned int, long, long, bool) (this=0x55556135a580, nframes=256, start_sample=16444105, end_sample=16444105, session_state_changing=false) at ../libs/ardour/route.cc:3987
#8  0x00007ffff7526ae3 in ARDOUR::MidiTrack::no_roll_unlocked(unsigned int, long, long, bool) (this=0x55556135a580, nframes=256, start_sample=16444105, end_sample=16444105, state_changing=false) at ../libs/ardour/midi_track.cc:356
#9  0x00007ffff76883fe in ARDOUR::Route::no_roll(unsigned int, long, long, bool) (this=0x55556135a580, nframes=256, start_sample=16444105, end_sample=16444105, session_state_changing=false) at ../libs/ardour/route.cc:3957
#10 0x00007ffff71f5aa4 in ARDOUR::Graph::process_one_route(ARDOUR::Route*) (this=0x555556ff0a00, route=0x55556135a580) at ../libs/ardour/graph.cc:670
#11 0x00007ffff71faa5a in ARDOUR::GraphNode::process() (this=0x55556135aa60) at ../libs/ardour/graphnode.cc:80
#12 0x00007ffff71f5cdd in ARDOUR::GraphNode::run(int) (this=0x55556135aa60, chain=1) at ../libs/ardour/ardour/graphnode.h:62
#13 0x00007ffff71f3578 in ARDOUR::Graph::run_one() (this=0x555556ff0a00) at ../libs/ardour/graph.cc:442
#14 0x00007ffff71f38f3 in ARDOUR::Graph::helper_thread() (this=0x555556ff0a00) at ../libs/ardour/graph.cc:470
#15 0x00007ffff71fa257 in boost::_mfi::mf0<void, ARDOUR::Graph>::operator()(ARDOUR::Graph*) const (this=0x7fffbeab6818, p=0x555556ff0a00) at /usr/include/boost/bind/mem_fn_template.hpp:49
#16 0x00007ffff71f9a47 in boost::_bi::list1<boost::_bi::value<ARDOUR::Graph*> >::operator()<boost::_mfi::mf0<void, ARDOUR::Graph>, boost::_bi::list0>(boost::_bi::type<void>, boost::_mfi::mf0<void, ARDOUR::Graph>&, boost::_bi::list0&, int) (this=0x7fffbeab6828, f=..., a=...) at /usr/include/boost/bind/bind.hpp:259
#17 0x00007ffff71f8f18 in boost::_bi::bind_t<void, boost::_mfi::mf0<void, ARDOUR::Graph>, boost::_bi::list1<boost::_bi::value<ARDOUR::Graph*> > >::operator()() (this=0x7fffbeab6818) at /usr/include/boost/bind/bind.hpp:1294
#18 0x00007ffff71f86c4 in boost::detail::function::void_function_obj_invoker0<boost::_bi::bind_t<void, boost::_mfi::mf0<void, ARDOUR::Graph>, boost::_bi::list1<boost::_bi::value<ARDOUR::Graph*> > >, void>::invoke(boost::detail::function::function_buffer&) (function_obj_ptr=...) at /usr/include/boost/function/function_template.hpp:158
#19 0x0000555555ba00c3 in boost::function0<void>::operator()() const (this=0x7fffbeab6810) at /usr/include/boost/function/function_template.hpp:763
#20 0x00007fffda446c35 in ARDOUR::JACKAudioBackend::_start_process_thread(void*) (arg=0x55555c1b6840) at ../libs/backends/jack/jack_audiobackend.cc:953
#21 0x00007ffff40e8e6e in start_thread (arg=0x7fffbeab7640) at pthread_create.c:463
#22 0x00007ffff36982af in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95