segmentation fault about samplv1

[rncbc]

unfortunately that's not easily reproducible if at all :(
what happens when you hit Reset from the MIDI Controller... dialog (right-click on the subject knob)- instead of Delete in the Help > Configure > Controllers ?

[tjingboem]

i made a new video to show:
sementation02-2018-03-25_21.35.14.mp4.zip
I guess this works fine...

[rncbc]

can you build with debug symbols (.configure --enable-debug) and try to run under gdb and have a back-trace of the segfault ?

you don't need to install it all the way, just follow these lines from the source tree:

$ ./autogen.sh clean
$ ./autogen.sh
$ ./configure --enable-debug
$ make
$ export LD_LIBRARY_PATH=$(pwd)/src
$ gdb src/samplv1_jack
gdb> run

returning to gdb prompt when segfaults, enter

gdb> bt

dump here the bt output (only the first page please).

seeya

[tjingboem]

I never worked with with gdb, but was able to do all the things you mentioned :)

I was able to build and run it from gdb. I got the segmentation fault but Samplv1 did not disappear completely this time, although it seems to be frozen.
Here is the output you asked for:

(gdb) run
Starting program: /media/menno/datae/Downloads/samplv1-master/src/samplv1_jack
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[New Thread 0x7fffe9e0f700 (LWP 10040)]
[New Thread 0x7fffded31700 (LWP 10041)]
[New Thread 0x7fffde530700 (LWP 10042)]
[New Thread 0x7fffde4af700 (LWP 10043)]
[New Thread 0x7fffdd4ed700 (LWP 10044)]
[New Thread 0x7fffde41c700 (LWP 10045)]
samplv1widget::newPreset()
samplv1widget::clearSampleFile()
[New Thread 0x7fffc9096700 (LWP 10046)]
[Thread 0x7fffc9096700 (LWP 10046) exited]
samplv1widget::loadSampleFile("/media/menno/datae/onderzoek/bluetests/freeze3.wav")

Thread 1 "samplv1_jack" received signal SIGSEGV, Segmentation fault.
0x00007ffff6f117c0 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
(gdb) bt
#0 0x00007ffff6f117c0 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#1 0x00007ffff6f1197b in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#2 0x00007ffff6edef7b in QTreeView::isIndexHidden(QModelIndex const&) const () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#3 0x00007ffff6ee0ea7 in QTreeView::visualRect(QModelIndex const&) const () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#4 0x00007ffff6e875da in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#5 0x00007ffff6e87ae8 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#6 0x00007fffec9e69d9 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5XcbQpa.so.5
#7 0x00007fffec9e6f49 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5XcbQpa.so.5
#8 0x00007fffec9ec3ac in ?? () from /usr/lib/x86_64-linux-gnu/libQt5XcbQpa.so.5
#9 0x00007ffff7e68abe in ?? () from /usr/lib/x86_64-linux-gnu/libQt5DBus.so.5
#10 0x00007ffff7e6a26e in ?? () from /usr/lib/x86_64-linux-gnu/libQt5DBus.so.5
#11 0x00007ffff68c7c01 in QObject::event(QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#12 0x00007ffff6c4305c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#13 0x00007ffff6c48516 in QApplication::notify(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#14 0x00007ffff689838b in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#15 0x00007ffff689a786 in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#16 0x00007ffff68ee3c3 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#17 0x00007ffff4467197 in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#18 0x00007ffff44673f0 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#19 0x00007ffff446749c in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#20 0x00007ffff68ee7cf in QEventDispatcherGlib::processEvents(QFlagsQEventLoop::ProcessEventsFlag) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#21 0x00007ffff6895b4a in QEventLoop::exec(QFlagsQEventLoop::ProcessEventsFlag) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#22 0x00007ffff6e3dd8d in QDialog::exec() () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#23 0x00007ffff71b8cb9 in samplv1widget::helpConfigure (this=0x89a2e0) at samplv1widget.cpp:1257
#24 0x00007ffff71f100f in samplv1widget::qt_static_metacall (_o=0x89a2e0, _c=QMetaObject::InvokeMetaMethod, _id=17, _a=0x7fffffffcc10) at .moc_ui/moc_samplv1widget.cpp:157
#25 0x00007ffff68c6d2a in QMetaObject::activate(QObject*, int, int, void**) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#26 0x00007ffff6c39412 in QAction::triggered(bool) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#27 0x00007ffff6c3b898 in QAction::activate(QAction::ActionEvent) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#28 0x00007ffff6dbde52 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#29 0x00007ffff6dc40ec in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#30 0x00007ffff6dc8060 in QMenu::mouseReleaseEvent(QMouseEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#31 0x00007ffff6c85fc8 in QWidget::event(QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#32 0x00007ffff6dc8ab3 in QMenu::event(QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#33 0x00007ffff6c4305c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#34 0x00007ffff6c48c19 in QApplication::notify(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#35 0x00007ffff689838b in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#36 0x00007ffff6c47b32 in QApplicationPrivate::sendMouseEvent(QWidget*, QMouseEvent*, QWidget*, QWidget*, QWidget**, QPointer&, bool) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#37 0x00007ffff6ca091d in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#38 0x00007ffff6ca2b7b in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#39 0x00007ffff6c4305c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#40 0x00007ffff6c48516 in QApplication::notify(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#41 0x00007ffff689838b in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#42 0x00007ffff4a734e1 in QGuiApplicationPrivate::processMouseEvent(QWindowSystemInterfacePrivate::MouseEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Gui.so.5
#43 0x00007ffff4a751a5 in QGuiApplicationPrivate::processWindowSystemEvent(QWindowSystemInterfacePrivate::WindowSystemEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Gui.so.5
#44 0x00007ffff4a58f08 in QWindowSystemInterface::sendWindowSystemEvents(QFlagsQEventLoop::ProcessEventsFlag) () from /usr/lib/x86_64-linux-gnu/libQt5Gui.so.5
#45 0x00007fffec9c8200 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5XcbQpa.so.5
#46 0x00007ffff4467197 in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#47 0x00007ffff44673f0 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#48 0x00007ffff446749c in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#49 0x00007ffff68ee7cf in QEventDispatcherGlib::processEvents(QFlagsQEventLoop::ProcessEventsFlag) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#50 0x00007ffff6895b4a in QEventLoop::exec(QFlagsQEventLoop::ProcessEventsFlag) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#51 0x00007ffff689dbec in QCoreApplication::exec() () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#52 0x000000000040c52f in samplv1_jack_application::exec (this=0x7fffffffda70) at samplv1_jack.cpp:758
#53 0x000000000040cdcc in main (argc=1, argv=0x7fffffffdbb8) at samplv1_jack.cpp:885
(gdb)

[rncbc]

seems weird environmental: it is not clear (to me) why samplv1_jack links to libQt5XcbQpa.so.5 and libQt5DBus.so.5 ...

can you tell me what distro, desktop environment, whether it's xorg, wayland, mir, unity, whatever?

[tjingboem]

Sure.
I'm on Linux Mint 18.3 (= Ubuntu-like), Cinnamon as WM, KXstudio, low-latency

[tjingboem]

I am not sure if it is related, but "our" version of Samplv1 has a somewhat different look from the one i see on your website:

As you see, the different submodules (LFO, DCF etc.) have no border like the one on your website. May this have to do with this QT link?

On a second machine, the whole problem does not exist. This machine runs the same Linux Mint 18.3. There, i can delete the CC without a crash - in standalone version as well as the LV2.

I'm not sure if it is interesting to pursue this problem any further if it is on my machine only?