Negative playspeed crashes ardour

[nathan-stewart]

If the playback speed slider is pulled to zero or negative, Ardour will crash:

ardour 4bc96f65cd9fee415292ecc59f06a31a3ac87fdb
repitch.lv2 149dc68809df326dbe6fe6fd3435db0252435e2b

Thread 18 "ardour-5.12.0" received signal SIGABRT, Aborted.
[Switching to Thread 0x7f3732d71700 (LWP 13451)]
0x00007f377a3e5428 in __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:54
54 ../sysdeps/unix/sysv/linux/raise.c: No such file or directory.
(gdb) bt
#0 0x00007f377a3e5428 in __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:54
#1 0x00007f377a3e702a in __GI_abort () at abort.c:89
#2 0x00007f377ad3784d in __gnu_cxx::__verbose_terminate_handler() () from /usr/lib/x86_64-linux-gnu/libstdc++.so.6
#3 0x00007f377ad356b6 in ?? () from /usr/lib/x86_64-linux-gnu/libstdc++.so.6
#4 0x00007f377ad35701 in std::terminate() () from /usr/lib/x86_64-linux-gnu/libstdc++.so.6
#5 0x00007f377ad35919 in __cxa_throw () from /usr/lib/x86_64-linux-gnu/libstdc++.so.6
#6 0x00007f377927d90a in RubberBand::Resamplers::D_SRC::resample(float const* const restrict*, float* const restrict*, int, float, bool) () from /usr/lib/x86_64-linux-gnu/librubberband.so.2
#7 0x00007f377927d173 in RubberBand::Resampler::resample(float const* const restrict*, float* const restrict*, int, float, bool) () from /usr/lib/x86_64-linux-gnu/librubberband.so.2
#8 0x00007f3779270f5e in RubberBand::RubberBandStretcher::Impl::consumeChannel(unsigned long, float const* const*, unsigned long, unsigned long, bool) () from /usr/lib/x86_64-linux-gnu/librubberband.so.2
#9 0x00007f3779287bcf in RubberBand::RubberBandStretcher::Impl::process(float const* const*, unsigned long, bool) () from /usr/lib/x86_64-linux-gnu/librubberband.so.2
#10 0x00007f36ff5f9461 in ?? () from /usr/local/lib/lv2/repitch.lv2/repitch.so
#11 0x00007f37823112c5 in lilv_instance_run (instance=0x4099420, sample_count=256) at /usr/include/lilv-0/lilv/lilv.h:1660
#12 0x00007f37823220ee in ARDOUR::LV2Plugin::run (this=0x408ae80, nframes=256, sync_work=false) at ../libs/ardour/lv2_plugin.cc:3088
#13 0x00007f378231fd91 in ARDOUR::LV2Plugin::connect_and_run (this=0x408ae80, bufs=..., start=474801, end=474801, speed=2.2204460492503131e-16, in_map=..., out_map=..., nframes=256, offset=0)
at ../libs/ardour/lv2_plugin.cc:2738
#14 0x00007f37820a01cc in ARDOUR::PluginInsert::connect_and_run (this=0x4089660, bufs=..., start=474801, end=474801, speed=2.2204460492503131e-16, nframes=256, offset=0, with_auto=true)
at ../libs/ardour/plugin_insert.cc:963
#15 0x00007f37820a1eaa in ARDOUR::PluginInsert::automate_and_run (this=0x4089660, bufs=..., start=474801, end=474801, speed=2.2204460492503131e-16, nframes=256) at ../libs/ardour/plugin_insert.cc:1222
#16 0x00007f37820a1bc1 in ARDOUR::PluginInsert::run (this=0x4089660, bufs=..., start_frame=474801, end_frame=474801, speed=2.2204460492503131e-16, nframes=256) at ../libs/ardour/plugin_insert.cc:1184
#17 0x00007f3782132cf4 in ARDOUR::Route::process_output_buffers (this=0x40696f0, bufs=..., start_frame=474801, end_frame=474801, nframes=256, declick=0, gain_automation_ok=true) at ../libs/ardour/route.cc:460
#18 0x00007f3782133dc0 in ARDOUR::Route::passthru (this=0x40696f0, bufs=..., start_frame=474801, end_frame=474801, nframes=256, declick=0) at ../libs/ardour/route.cc:618
#19 0x00007f37821464cc in ARDOUR::Route::roll (this=0x40696f0, nframes=256, start_frame=474801, end_frame=474801, declick=0) at ../libs/ardour/route.cc:3588
#20 0x00007f3781d388e9 in ARDOUR::Graph::process_one_route (this=0x37f6010, route=0x40696f0) at ../libs/ardour/graph.cc:611
#21 0x00007f3781d3e330 in ARDOUR::GraphNode::process (this=0x4069b90) at ../libs/ardour/graphnode.cc:79
#22 0x00007f3781d36c85 in ARDOUR::Graph::run_one (this=0x37f6010) at ../libs/ardour/graph.cc:420
#23 0x00007f3781d36eca in ARDOUR::Graph::helper_thread (this=0x37f6010) at ../libs/ardour/graph.cc:438
#24 0x00007f3781d3da2d in boost::_mfi::mf0<void, ARDOUR::Graph>::operator() (this=0x7f3732d70c58, p=0x37f6010) at /usr/include/boost/bind/mem_fn_template.hpp:49
#25 0x00007f3781d3d146 in boost::_bi::list1<boost::_bi::valueARDOUR::Graph* >::operator()<boost::_mfi::mf0<void, ARDOUR::Graph>, boost::_bi::list0> (this=0x7f3732d70c68, f=..., a=...)
at /usr/include/boost/bind/bind.hpp:253
#26 0x00007f3781d3c5d6 in boost::_bi::bind_t<void, boost::_mfi::mf0<void, ARDOUR::Graph>, boost::_bi::list1<boost::_bi::valueARDOUR::Graph* > >::operator() (this=0x7f3732d70c58)
at /usr/include/boost/bind/bind.hpp:893
#27 0x00007f3781d3bdd0 in boost::detail::function::void_function_obj_invoker0<boost::_bi::bind_t<void, boost::_mfi::mf0<void, ARDOUR::Graph>, boost::_bi::list1<boost::_bi::valueARDOUR::Graph* > >, void>::invoke (function_obj_ptr=...) at /usr/include/boost/function/function_template.hpp:159
#28 0x0000000000711e5f in boost::function0::operator() (this=0x7f3732d70c50) at /usr/include/boost/function/function_template.hpp:773
#29 0x00007f375a6fed44 in ARDOUR::JACKAudioBackend::_start_process_thread (arg=0x2897560) at ../libs/backends/jack/jack_audiobackend.cc:936
#30 0x00007f377bb576ba in start_thread (arg=0x7f3732d71700) at pthread_create.c:333
#31 0x00007f377a4b741d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

[x42]

This is a bug with Ardour, processing zero samples at non-zero speed.

start=474801, end=474801, speed=2.2204460492503131e-16

Can you double check Ardour > Menu > Help > About? The git revision that you reference does not match line numbers in the backtrace. e.g.

#12 0x00007f37823220ee in ARDOUR::LV2Plugin::run (this=0x408ae80, nframes=256, sync_work=false) at ../libs/ardour/lv2_plugin.cc:3088

You mention ardour 4bc96f65cd9fee415292ecc59f06a31a3ac87fdb but https://github.com/Ardour/ardour/blob/4bc96f65cd9fee415292ecc59f06a31a3ac87fdb/libs/ardour/lv2_plugin.cc#L3088 is an empty line.

It seems you're still running 5.12 or have not re-configured Ardour correctly since.

PS. it's not actually negative speed that is the issue, but the transition near zero from positive to negative.