MPV deadlock on exit

MPV deadlock on futex in mpv_terminate_destroy when exiting while video is still playing

#0  0x00007ffff4cf78ca in __futex_abstimed_wait_common64 () at /usr/lib/libpthread.so.0
#1  0x00007ffff4cf1270 in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#2  0x00007ffff5d898ec in  () at /usr/lib/libmpv.so.1
#3  0x00007ffff5e228fc in  () at /usr/lib/libmpv.so.1
#4  0x00007ffff5dca62c in  () at /usr/lib/libmpv.so.1
#5  0x00007ffff5dc19c4 in  () at /usr/lib/libmpv.so.1
#6  0x00007ffff5da3339 in  () at /usr/lib/libmpv.so.1
#7  0x000000010006391f in Vivy::MpvContainer::closeMpv() (this=0x10080b3a0) at /home/elliu/Projects/Vivy/src/UI/DocumentViews/MpvContainer.cc:72
#8  0x0000000100063976 in Vivy::MpvContainer::~MpvContainer() (this=0x10080b3a0, __in_chrg=<optimized out>) at /home/elliu/Projects/Vivy/src/UI/DocumentViews/MpvContainer.cc:78
#9  0x00000001000639c4 in Vivy::MpvContainer::~MpvContainer() (this=0x10080b3a0, __in_chrg=<optimized out>) at /home/elliu/Projects/Vivy/src/UI/DocumentViews/MpvContainer.cc:79
#10 0x00007ffff53a1b7e in QObjectPrivate::deleteChildren() () at /usr/lib/libQt5Core.so.5
#11 0x00007ffff7a635ce in QWidget::~QWidget() () at /usr/lib/libQt5Widgets.so.5
#12 0x000000010002a27e in Vivy::VideoView::~VideoView() (this=0x100eb3ff0, __in_chrg=<optimized out>) at /home/elliu/Projects/Vivy/src/UI/DocumentViews/VideoView.hh:13
#13 0x000000010002a2a0 in Vivy::VideoView::~VideoView() (this=0x100eb3ff0, __in_chrg=<optimized out>) at /home/elliu/Projects/Vivy/src/UI/DocumentViews/VideoView.hh:13
#14 0x00007ffff53a1b7e in QObjectPrivate::deleteChildren() () at /usr/lib/libQt5Core.so.5
#15 0x00007ffff7a635ce in QWidget::~QWidget() () at /usr/lib/libQt5Widgets.so.5
#16 0x00007ffff7b4a88a in QDockWidget::~QDockWidget() () at /usr/lib/libQt5Widgets.so.5
#17 0x000000010005a4b1 in Vivy::AbstractDocumentView::deleteAllContent() (this=0x100942e30) at /home/elliu/Projects/Vivy/src/UI/AbstractDocumentView.cc:33
#18 0x0000000100081a5b in Vivy::VivyDocumentView::closeDocument() (this=0x100942e30) at /home/elliu/Projects/Vivy/src/UI/VivyDocumentView.cc:163
#19 0x0000000100080bac in Vivy::VivyDocumentView::~VivyDocumentView() (this=0x100942e30, __in_chrg=<optimized out>) at /home/elliu/Projects/Vivy/src/UI/VivyDocumentView.cc:51
#20 0x0000000100080c24 in Vivy::VivyDocumentView::~VivyDocumentView() (this=0x100942e30, __in_chrg=<optimized out>) at /home/elliu/Projects/Vivy/src/UI/VivyDocumentView.cc:52
#21 0x00007ffff53a1b7e in QObjectPrivate::deleteChildren() () at /usr/lib/libQt5Core.so.5
#22 0x00007ffff7a635ce in QWidget::~QWidget() () at /usr/lib/libQt5Widgets.so.5
#23 0x00007ffff7be371a in QStackedWidget::~QStackedWidget() () at /usr/lib/libQt5Widgets.so.5
#24 0x00007ffff53a1b7e in QObjectPrivate::deleteChildren() () at /usr/lib/libQt5Core.so.5
#25 0x00007ffff7a635ce in QWidget::~QWidget() () at /usr/lib/libQt5Widgets.so.5
#26 0x00007ffff7c0793a in QTabWidget::~QTabWidget() () at /usr/lib/libQt5Widgets.so.5
#27 0x00007ffff53a1b7e in QObjectPrivate::deleteChildren() () at /usr/lib/libQt5Core.so.5
#28 0x00007ffff7a635ce in QWidget::~QWidget() () at /usr/lib/libQt5Widgets.so.5
#29 0x000000010002a202 in Vivy::MainWindow::~MainWindow() (this=0x7fffffffd790, __in_chrg=<optimized out>) at /home/elliu/Projects/Vivy/src/UI/MainWindow.hh:20
#30 0x0000000100085924 in Vivy::VivyApplication::exec() (this=0x7fffffffd820) at /home/elliu/Projects/Vivy/src/VivyApplication.cc:65
#31 0x000000010005746a in main(int, char**) (argc=1, argv=0x7fffffffd9d8) at /home/elliu/Projects/Vivy/src/Main.cc:7