Bug 419952

Summary: Crash while adding video/picture with 0 tracks on timeline
Product: [Applications] kdenlive Reporter: Evgeny <s404.gordon>
Component: Rendering & ExportAssignee: Jean-Baptiste Mardelle <jb>
Status: RESOLVED FIXED    
Severity: crash CC: fritzibaby
Priority: NOR    
Version First Reported In: 19.12.3   
Target Milestone: ---   
Platform: Ubuntu   
OS: Linux   
Latest Commit: Version Fixed In: 20.04
Sentry Crash Report:

Description Evgeny 2020-04-11 12:09:21 UTC 
Application: kdenlive (19.12.3)

Qt Version: 5.12.5
Frameworks Version: 5.68.0
Operating System: Linux 5.4.0-21-generic x86_64
Windowing system: X11
Distribution: Ubuntu Focal Fossa (development branch)

-- Information about the crash:
- What I was doing when the application crashed:
go to configure kdenlive -> project defaults
set video & audio tracks to 0
create new project
add video or picture to project media

The crash can be reproduced every time.

-- Backtrace:
Application: Kdenlive (kdenlive), signal: Aborted
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0x7f7890708900 (LWP 4104))]

Thread 43 (Thread 0x7f77be7fc700 (LWP 4172)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f77ec069244) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x7f77ec0692a8, cond=0x7f77ec069218) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x7f77ec069218, mutex=0x7f77ec0692a8) at pthread_cond_wait.c:638
#3  0x00007f7873064ca6 in  () at /lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#5  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 42 (Thread 0x7f77beffd700 (LWP 4171)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f77ec069094) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x7f77ec0690f8, cond=0x7f77ec069068) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x7f77ec069068, mutex=0x7f77ec0690f8) at pthread_cond_wait.c:638
#3  0x00007f7873064ca6 in  () at /lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#5  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 41 (Thread 0x7f77bf7fe700 (LWP 4170)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f77ec068ee4) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x7f77ec068f48, cond=0x7f77ec068eb8) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x7f77ec068eb8, mutex=0x7f77ec068f48) at pthread_cond_wait.c:638
#3  0x00007f7873064ca6 in  () at /lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#5  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 40 (Thread 0x7f77bffff700 (LWP 4169)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f77ec068d30) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x7f77ec068d98, cond=0x7f77ec068d08) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x7f77ec068d08, mutex=0x7f77ec068d98) at pthread_cond_wait.c:638
#3  0x00007f7873064ca6 in  () at /lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#5  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 39 (Thread 0x7f77e4ca1700 (LWP 4168)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f77ec068b80) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x7f77ec068be8, cond=0x7f77ec068b58) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x7f77ec068b58, mutex=0x7f77ec068be8) at pthread_cond_wait.c:638
#3  0x00007f7873064ca6 in  () at /lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#5  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 38 (Thread 0x7f77e54a2700 (LWP 4167)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f77ec0689d0) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x7f77ec068a38, cond=0x7f77ec0689a8) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x7f77ec0689a8, mutex=0x7f77ec068a38) at pthread_cond_wait.c:638
#3  0x00007f7873064ca6 in  () at /lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#5  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 37 (Thread 0x7f77e5ca3700 (LWP 4166)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f77ec068820) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x7f77ec068888, cond=0x7f77ec0687f8) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x7f77ec0687f8, mutex=0x7f77ec068888) at pthread_cond_wait.c:638
#3  0x00007f7873064ca6 in  () at /lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#5  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 36 (Thread 0x7f77e64a4700 (LWP 4165)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f77ec068674) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x7f77ec0686d8, cond=0x7f77ec068648) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x7f77ec068648, mutex=0x7f77ec0686d8) at pthread_cond_wait.c:638
#3  0x00007f7873064ca6 in  () at /lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#5  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 35 (Thread 0x7f77e6ca5700 (LWP 4164)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f77ec0684c4) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x7f77ec068528, cond=0x7f77ec068498) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x7f77ec068498, mutex=0x7f77ec068528) at pthread_cond_wait.c:638
#3  0x00007f7873064ca6 in  () at /lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#5  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 34 (Thread 0x7f7849efa700 (LWP 4145)):
#0  __GI___libc_read (nbytes=10, buf=0x7f7849ef9c2e, fd=33) at ../sysdeps/unix/sysv/linux/read.c:26
#1  __GI___libc_read (fd=33, buf=0x7f7849ef9c2e, nbytes=10) at ../sysdeps/unix/sysv/linux/read.c:24
#2  0x00007f78939b7955 in pa_read () at /usr/lib/x86_64-linux-gnu/pulseaudio/libpulsecommon-13.99.so
#3  0x00007f7897483416 in pa_mainloop_prepare () at /lib/x86_64-linux-gnu/libpulse.so.0
#4  0x00007f7897483eb4 in pa_mainloop_iterate () at /lib/x86_64-linux-gnu/libpulse.so.0
#5  0x00007f786a311abf in  () at /lib/x86_64-linux-gnu/libSDL2-2.0.so.0
#6  0x00007f786a2636be in  () at /lib/x86_64-linux-gnu/libSDL2-2.0.so.0
#7  0x00007f786a2b3720 in  () at /lib/x86_64-linux-gnu/libSDL2-2.0.so.0
#8  0x00007f786a32c13d in  () at /lib/x86_64-linux-gnu/libSDL2-2.0.so.0
#9  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#10 0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 33 (Thread 0x7f781a7fc700 (LWP 4144)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f781d64cefc) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x7f781d64cea8, cond=0x7f781d64ced0) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x7f781d64ced0, mutex=0x7f781d64cea8) at pthread_cond_wait.c:638
#3  0x00007f789a0dee79 in  () at /lib/x86_64-linux-gnu/libmlt.so.6
#4  0x000056365785c671 in  ()
#5  0x00007f78980939c2 in  () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#7  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 32 (Thread 0x7f781affd700 (LWP 4143)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f781d64ce38) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x7f781d64ce40, cond=0x7f781d64ce10) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x7f781d64ce10, mutex=0x7f781d64ce40) at pthread_cond_wait.c:638
#3  0x00007f786722aa73 in  () at /usr/lib/x86_64-linux-gnu/mlt/libmltsdl2.so
#4  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#5  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 31 (Thread 0x7f7849f3b700 (LWP 4142)):
#0  __GI___libc_read (nbytes=10, buf=0x7f7849f3ac6e, fd=22) at ../sysdeps/unix/sysv/linux/read.c:26
#1  __GI___libc_read (fd=22, buf=0x7f7849f3ac6e, nbytes=10) at ../sysdeps/unix/sysv/linux/read.c:24
#2  0x00007f78939b7955 in pa_read () at /usr/lib/x86_64-linux-gnu/pulseaudio/libpulsecommon-13.99.so
#3  0x00007f7897483416 in pa_mainloop_prepare () at /lib/x86_64-linux-gnu/libpulse.so.0
#4  0x00007f7897483eb4 in pa_mainloop_iterate () at /lib/x86_64-linux-gnu/libpulse.so.0
#5  0x00007f7897483f70 in pa_mainloop_run () at /lib/x86_64-linux-gnu/libpulse.so.0
#6  0x00007f786a311cb3 in  () at /lib/x86_64-linux-gnu/libSDL2-2.0.so.0
#7  0x00007f786a2b3720 in  () at /lib/x86_64-linux-gnu/libSDL2-2.0.so.0
#8  0x00007f786a32c13d in  () at /lib/x86_64-linux-gnu/libSDL2-2.0.so.0
#9  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#10 0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 30 (Thread 0x7f77e77f6700 (LWP 4141)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x56365b1f4604) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x56365b1f4668, cond=0x56365b1f45d8) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x56365b1f45d8, mutex=0x56365b1f4668) at pthread_cond_wait.c:638
#3  0x00007f7873064ca6 in  () at /lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#5  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 29 (Thread 0x7f77e7ff7700 (LWP 4140)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x56365b1f4454) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x56365b1f44b8, cond=0x56365b1f4428) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x56365b1f4428, mutex=0x56365b1f44b8) at pthread_cond_wait.c:638
#3  0x00007f7873064ca6 in  () at /lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#5  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 28 (Thread 0x7f77e87f8700 (LWP 4139)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x56365b1f42a4) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x56365b1f4308, cond=0x56365b1f4278) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x56365b1f4278, mutex=0x56365b1f4308) at pthread_cond_wait.c:638
#3  0x00007f7873064ca6 in  () at /lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#5  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 27 (Thread 0x7f77e8ff9700 (LWP 4138)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x56365b1f40f4) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x56365b1f4158, cond=0x56365b1f40c8) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x56365b1f40c8, mutex=0x56365b1f4158) at pthread_cond_wait.c:638
#3  0x00007f7873064ca6 in  () at /lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#5  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 26 (Thread 0x7f77e97fa700 (LWP 4137)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x56365b1f3f44) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x56365b1f3fa8, cond=0x56365b1f3f18) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x56365b1f3f18, mutex=0x56365b1f3fa8) at pthread_cond_wait.c:638
#3  0x00007f7873064ca6 in  () at /lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#5  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 25 (Thread 0x7f77e9ffb700 (LWP 4136)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x56365b1f3d94) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x56365b1f3df8, cond=0x56365b1f3d68) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x56365b1f3d68, mutex=0x56365b1f3df8) at pthread_cond_wait.c:638
#3  0x00007f7873064ca6 in  () at /lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#5  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 24 (Thread 0x7f77ea7fc700 (LWP 4135)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x56365b1f3be4) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x56365b1f3c48, cond=0x56365b1f3bb8) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x56365b1f3bb8, mutex=0x56365b1f3c48) at pthread_cond_wait.c:638
#3  0x00007f7873064ca6 in  () at /lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#5  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 23 (Thread 0x7f77eaffd700 (LWP 4134)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x56365b1f3a30) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x56365b1f3a98, cond=0x56365b1f3a08) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x56365b1f3a08, mutex=0x56365b1f3a98) at pthread_cond_wait.c:638
#3  0x00007f7873064ca6 in  () at /lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#5  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 22 (Thread 0x7f77eb7fe700 (LWP 4133)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x56365b1f3880) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x56365b1f38e8, cond=0x56365b1f3858) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x56365b1f3858, mutex=0x56365b1f38e8) at pthread_cond_wait.c:638
#3  0x00007f7873064ca6 in  () at /lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#5  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 21 (Thread 0x7f77ebfff700 (LWP 4132)):
#0  0x00007f788436562f in avio_r8 () at /lib/x86_64-linux-gnu/libavformat.so.58
#1  0x00007f7884365cd2 in avio_rb16 () at /lib/x86_64-linux-gnu/libavformat.so.58
#2  0x00007f7884365d2f in avio_rb32 () at /lib/x86_64-linux-gnu/libavformat.so.58
#3  0x00007f78843ea760 in  () at /lib/x86_64-linux-gnu/libavformat.so.58
#4  0x00007f78843e6ce5 in  () at /lib/x86_64-linux-gnu/libavformat.so.58
#5  0x00007f78843e6ce5 in  () at /lib/x86_64-linux-gnu/libavformat.so.58
#6  0x00007f78843e6ce5 in  () at /lib/x86_64-linux-gnu/libavformat.so.58
#7  0x00007f78843e6ce5 in  () at /lib/x86_64-linux-gnu/libavformat.so.58
#8  0x00007f78843f5a64 in  () at /lib/x86_64-linux-gnu/libavformat.so.58
#9  0x00007f78843e6ce5 in  () at /lib/x86_64-linux-gnu/libavformat.so.58
#10 0x00007f78843e7215 in  () at /lib/x86_64-linux-gnu/libavformat.so.58
#11 0x00007f78843e6ce5 in  () at /lib/x86_64-linux-gnu/libavformat.so.58
#12 0x00007f78843efcd7 in  () at /lib/x86_64-linux-gnu/libavformat.so.58
#13 0x00007f78844b68e6 in avformat_open_input () at /lib/x86_64-linux-gnu/libavformat.so.58
#14 0x00007f78846ab3f2 in  () at /usr/lib/x86_64-linux-gnu/mlt/libmltavformat.so
#15 0x00007f78846af087 in producer_avformat_init () at /usr/lib/x86_64-linux-gnu/mlt/libmltavformat.so
#16 0x00007f789a0e3892 in mlt_factory_producer () at /lib/x86_64-linux-gnu/libmlt.so.6
#17 0x00007f789a0b067e in Mlt::Producer::Producer(mlt_profile_s*, char const*, char const*) () at /lib/x86_64-linux-gnu/libmlt++.so.3
#18 0x00005636577f6f93 in  ()
#19 0x00005636577fb3e8 in  ()
#20 0x0000563657801e0a in  ()
#21 0x0000563657803c5c in  ()
#22 0x0000563657804204 in  ()
#23 0x00007f789a210cb5 in QtConcurrent::ThreadEngineBase::run() () at /lib/x86_64-linux-gnu/libQt5Concurrent.so.5
#24 0x00007f7898096f72 in  () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#25 0x00007f78980939c2 in  () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#26 0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#27 0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 20 (Thread 0x7f781880f700 (LWP 4131)):
#0  futex_abstimed_wait_cancelable (private=<optimized out>, abstime=0x7f781880ebd0, clockid=<optimized out>, expected=0, futex_word=0x7f77f8004b10) at ../sysdeps/nptl/futex-internal.h:320
#1  __pthread_cond_wait_common (abstime=0x7f781880ebd0, clockid=<optimized out>, mutex=0x7f77f8004ac0, cond=0x7f77f8004ae8) at pthread_cond_wait.c:520
#2  __pthread_cond_timedwait (cond=0x7f77f8004ae8, mutex=0x7f77f8004ac0, abstime=0x7f781880ebd0) at pthread_cond_wait.c:656
#3  0x00007f7898099a6c in QWaitCondition::wait(QMutex*, QDeadlineTimer) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f7898099bbb in QWaitCondition::wait(QMutex*, unsigned long) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f7898097161 in  () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f78980939c2 in  () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#8  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 19 (Thread 0x7f7819010700 (LWP 4130)):
#0  futex_abstimed_wait_cancelable (private=<optimized out>, abstime=0x7f781900fbd0, clockid=<optimized out>, expected=0, futex_word=0x7f7860005204) at ../sysdeps/nptl/futex-internal.h:320
#1  __pthread_cond_wait_common (abstime=0x7f781900fbd0, clockid=<optimized out>, mutex=0x7f78600051b0, cond=0x7f78600051d8) at pthread_cond_wait.c:520
#2  __pthread_cond_timedwait (cond=0x7f78600051d8, mutex=0x7f78600051b0, abstime=0x7f781900fbd0) at pthread_cond_wait.c:656
#3  0x00007f7898099a6c in QWaitCondition::wait(QMutex*, QDeadlineTimer) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f7898099bbb in QWaitCondition::wait(QMutex*, unsigned long) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f7898097161 in  () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f78980939c2 in  () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#8  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 18 (Thread 0x7f781b7fe700 (LWP 4126)):
#0  0x00007f7897bc896f in __GI___poll (fds=0x7f780c0029e0, nfds=1, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007f7893b741ae in  () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f7893b742e3 in g_main_context_iteration () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f78982b28c3 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f789825982b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f7898092775 in QThread::exec() () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f78980939c2 in  () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#8  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 17 (Thread 0x7f781bfff700 (LWP 4125)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x563662e54944) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x563662e548f0, cond=0x563662e54918) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x563662e54918, mutex=0x563662e548f0) at pthread_cond_wait.c:638
#3  0x00007f7898099aff in QWaitCondition::wait(QMutex*, QDeadlineTimer) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f7898099bf1 in QWaitCondition::wait(QMutex*, unsigned long) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f789937b0d9 in  () at /lib/x86_64-linux-gnu/libQt5Quick.so.5
#6  0x00007f789937b37d in  () at /lib/x86_64-linux-gnu/libQt5Quick.so.5
#7  0x00007f78980939c2 in  () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#9  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 16 (Thread 0x7f7848da3700 (LWP 4124)):
#0  0x00007f7893b70734 in  () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#1  0x00007f7893b72185 in  () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f7893b7366b in g_main_context_prepare () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f7893b740db in  () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007f7893b742e3 in g_main_context_iteration () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007f78982b28c3 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f789825982b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f7898092775 in QThread::exec() () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f78980939c2 in  () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#9  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#10 0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 15 (Thread 0x7f78495b6700 (LWP 4123)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x563661d47044) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x563661d46ff0, cond=0x563661d47018) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x563661d47018, mutex=0x563661d46ff0) at pthread_cond_wait.c:638
#3  0x00007f7898099aff in QWaitCondition::wait(QMutex*, QDeadlineTimer) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f7898099bf1 in QWaitCondition::wait(QMutex*, unsigned long) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f789937b0d9 in  () at /lib/x86_64-linux-gnu/libQt5Quick.so.5
#6  0x00007f789937b37d in  () at /lib/x86_64-linux-gnu/libQt5Quick.so.5
#7  0x00007f78980939c2 in  () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#9  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 14 (Thread 0x7f784abfd700 (LWP 4118)):
#0  0x00007f7897bc896f in __GI___poll (fds=0x7f7840006200, nfds=1, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007f7893b741ae in  () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f7893b742e3 in g_main_context_iteration () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f78982b28c3 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f789825982b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f7898092775 in QThread::exec() () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f78992eee0a in  () at /lib/x86_64-linux-gnu/libQt5Quick.so.5
#7  0x00007f78980939c2 in  () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#9  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 13 (Thread 0x7f784b7fe700 (LWP 4117)):
#0  __GI___libc_read (nbytes=16, buf=0x7f784b7fda70, fd=20) at ../sysdeps/unix/sysv/linux/read.c:26
#1  __GI___libc_read (fd=20, buf=0x7f784b7fda70, nbytes=16) at ../sysdeps/unix/sysv/linux/read.c:24
#2  0x00007f7893bbc89f in  () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f7893b73cfe in g_main_context_check () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007f7893b74152 in  () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007f7893b742e3 in g_main_context_iteration () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#6  0x00007f78982b28c3 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f789825982b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f7898092775 in QThread::exec() () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#9  0x00007f789900b3a9 in  () at /lib/x86_64-linux-gnu/libQt5Qml.so.5
#10 0x00007f78980939c2 in  () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#11 0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#12 0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 12 (Thread 0x7f784bfff700 (LWP 4116)):
#0  __GI___libc_read (nbytes=16, buf=0x7f784bffea50, fd=19) at ../sysdeps/unix/sysv/linux/read.c:26
#1  __GI___libc_read (fd=19, buf=0x7f784bffea50, nbytes=16) at ../sysdeps/unix/sysv/linux/read.c:24
#2  0x00007f7893bbc89f in  () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f7893b73cfe in g_main_context_check () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007f7893b74152 in  () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007f7893b742e3 in g_main_context_iteration () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#6  0x00007f78982b28c3 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f789825982b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f7898092775 in QThread::exec() () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#9  0x00007f78992eee0a in  () at /lib/x86_64-linux-gnu/libQt5Quick.so.5
#10 0x00007f78980939c2 in  () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#11 0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#12 0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 11 (Thread 0x7f785d96e700 (LWP 4115)):
#0  0x00007f7897bc896f in __GI___poll (fds=0x7f78500029e0, nfds=1, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007f7893b741ae in  () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f7893b742e3 in g_main_context_iteration () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f78982b28c3 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f789825982b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f7898092775 in QThread::exec() () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f789900b3a9 in  () at /lib/x86_64-linux-gnu/libQt5Qml.so.5
#7  0x00007f78980939c2 in  () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#9  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 10 (Thread 0x7f785ebaf700 (LWP 4114)):
#0  0x00007f7897bc896f in __GI___poll (fds=0x7f784c0025e0, nfds=1, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007f7893b741ae in  () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f7893b742e3 in g_main_context_iteration () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f78982b28c3 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f789825982b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f7898092775 in QThread::exec() () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f789900b3a9 in  () at /lib/x86_64-linux-gnu/libQt5Qml.so.5
#7  0x00007f78980939c2 in  () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#9  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 9 (Thread 0x7f786493b700 (LWP 4113)):
#0  0x00007f7897bc896f in __GI___poll (fds=0x7f78540029e0, nfds=1, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007f7893b741ae in  () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f7893b742e3 in g_main_context_iteration () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f78982b28a5 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f789825982b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f7898092775 in QThread::exec() () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f789900b3a9 in  () at /lib/x86_64-linux-gnu/libQt5Qml.so.5
#7  0x00007f78980939c2 in  () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#9  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 8 (Thread 0x7f7865bf2700 (LWP 4112)):
#0  0x00007ffc14bcf6cb in  ()
#1  0x00007ffc14bcf918 in clock_gettime ()
#2  0x00007f7897b93235 in __GI___clock_gettime (clock_id=1, tp=0x7f7865bf19f0) at ../sysdeps/unix/sysv/linux/clock_gettime.c:38
#3  0x00007f78982b2185 in  () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f78982b0a1d in QTimerInfoList::updateCurrentTime() () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f78982b0ff9 in QTimerInfoList::timerWait(timespec&) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f78982b2616 in  () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f7893b7372f in g_main_context_prepare () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#8  0x00007f7893b740db in  () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#9  0x00007f7893b742e3 in g_main_context_iteration () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#10 0x00007f78982b28c3 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#11 0x00007f789825982b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#12 0x00007f7898092775 in QThread::exec() () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#13 0x00007f789900b3a9 in  () at /lib/x86_64-linux-gnu/libQt5Qml.so.5
#14 0x00007f78980939c2 in  () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#15 0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#16 0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 7 (Thread 0x7f7866ed9700 (LWP 4111)):
#0  futex_abstimed_wait_cancelable (private=<optimized out>, abstime=0x7f7866ed8bd0, clockid=<optimized out>, expected=0, futex_word=0x56365905b6c4) at ../sysdeps/nptl/futex-internal.h:320
#1  __pthread_cond_wait_common (abstime=0x7f7866ed8bd0, clockid=<optimized out>, mutex=0x56365905b670, cond=0x56365905b698) at pthread_cond_wait.c:520
#2  __pthread_cond_timedwait (cond=0x56365905b698, mutex=0x56365905b670, abstime=0x7f7866ed8bd0) at pthread_cond_wait.c:656
#3  0x00007f7898099a6c in QWaitCondition::wait(QMutex*, QDeadlineTimer) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f7898099bbb in QWaitCondition::wait(QMutex*, unsigned long) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f7898097161 in  () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f78980939c2 in  () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#8  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 6 (Thread 0x7f7885f38700 (LWP 4110)):
#0  0x00007f7893b7209d in g_source_ref () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#1  0x00007f7893b72168 in  () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f7893b73aff in g_main_context_check () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f7893b74152 in  () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007f7893b742e3 in g_main_context_iteration () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007f78982b28c3 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f789825982b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f7898092775 in QThread::exec() () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f7899dd2efa in  () at /lib/x86_64-linux-gnu/libQt5DBus.so.5
#9  0x00007f78980939c2 in  () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#10 0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#11 0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 5 (Thread 0x7f78877fe700 (LWP 4109)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f78880046cc) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x7f7888004678, cond=0x7f78880046a0) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x7f78880046a0, mutex=0x7f7888004678) at pthread_cond_wait.c:638
#3  0x00007f788dea734b in  () at /usr/lib/x86_64-linux-gnu/dri/i965_dri.so
#4  0x00007f788dea6f5b in  () at /usr/lib/x86_64-linux-gnu/dri/i965_dri.so
#5  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#6  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 4 (Thread 0x7f7887fff700 (LWP 4108)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f78880046cc) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x7f7888004678, cond=0x7f78880046a0) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x7f78880046a0, mutex=0x7f7888004678) at pthread_cond_wait.c:638
#3  0x00007f788dea734b in  () at /usr/lib/x86_64-linux-gnu/dri/i965_dri.so
#4  0x00007f788dea6f5b in  () at /usr/lib/x86_64-linux-gnu/dri/i965_dri.so
#5  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#6  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 3 (Thread 0x7f788cf34700 (LWP 4107)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f78880046cc) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x7f7888004678, cond=0x7f78880046a0) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x7f78880046a0, mutex=0x7f7888004678) at pthread_cond_wait.c:638
#3  0x00007f788dea734b in  () at /usr/lib/x86_64-linux-gnu/dri/i965_dri.so
#4  0x00007f788dea6f5b in  () at /usr/lib/x86_64-linux-gnu/dri/i965_dri.so
#5  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#6  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 2 (Thread 0x7f788d735700 (LWP 4106)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f78880046cc) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x7f7888004678, cond=0x7f78880046a0) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x7f78880046a0, mutex=0x7f7888004678) at pthread_cond_wait.c:638
#3  0x00007f788dea734b in  () at /usr/lib/x86_64-linux-gnu/dri/i965_dri.so
#4  0x00007f788dea6f5b in  () at /usr/lib/x86_64-linux-gnu/dri/i965_dri.so
#5  0x00007f789743d609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#6  0x00007f7897bd5103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 1 (Thread 0x7f7890708900 (LWP 4104)):
[KCrash Handler]
#6  __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50
#7  0x00007f7897ad8859 in __GI_abort () at abort.c:79
#8  0x00007f7897e92951 in  () at /lib/x86_64-linux-gnu/libstdc++.so.6
#9  0x00007f7897e9e47c in  () at /lib/x86_64-linux-gnu/libstdc++.so.6
#10 0x00007f7897e9e4e7 in  () at /lib/x86_64-linux-gnu/libstdc++.so.6
#11 0x00007f7897e9e799 in  () at /lib/x86_64-linux-gnu/libstdc++.so.6
#12 0x00007f7897e953be in std::__throw_out_of_range(char const*) () at /lib/x86_64-linux-gnu/libstdc++.so.6
#13 0x000056365795fb7e in  ()
#14 0x00005636579233ef in  ()
#15 0x00005636579ca5eb in  ()
#16 0x00005636578c061c in  ()
#17 0x00005636578c0a45 in  ()
#18 0x00007f78982867b8 in QMetaObject::activate(QObject*, int, int, void**) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#19 0x00007f789829385e in QTimer::timeout(QTimer::QPrivateSignal) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#20 0x00007f7898287045 in QObject::event(QEvent*) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#21 0x00007f78997e6a66 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /lib/x86_64-linux-gnu/libQt5Widgets.so.5
#22 0x00007f78997f00e0 in QApplication::notify(QObject*, QEvent*) () at /lib/x86_64-linux-gnu/libQt5Widgets.so.5
#23 0x00007f789825ac8a in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#24 0x00007f78982b1bf0 in QTimerInfoList::activateTimers() () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#25 0x00007f78982b2524 in  () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#26 0x00007f7893b73fbd in g_main_context_dispatch () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#27 0x00007f7893b74240 in  () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#28 0x00007f7893b742e3 in g_main_context_iteration () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#29 0x00007f78982b28a5 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#30 0x00007f789825982b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#31 0x00007f7898261596 in QCoreApplication::exec() () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#32 0x000056365756a79d in  ()
#33 0x00007f7897ada0b3 in __libc_start_main (main=0x5636575694c0, argc=1, argv=0x7ffc14a99588, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7ffc14a99578) at ../csu/libc-start.c:308
#34 0x0000563657571c3e in _start ()
[Inferior 1 (process 4104) detached]
Comment 1 emohr 2020-04-12 13:38:00 UTC 
This bug is solved with the upcoming 20.04 version. You can't delete all video/audio tracks anymore.

Please try with the current Kdenlive_Nightly_Appimage
https://binary-factory.kde.org/job/Kdenlive_Nightly_Appimage_Build/lastSuccessfulBuild/artifact/