GNU gdb (GDB) 8.1
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Attaching to process 2122
[New LWP 2137]
[New LWP 2176]
[New LWP 2195]
[New LWP 2204]
[New LWP 2219]
[New LWP 2241]
[New LWP 2270]
[New LWP 2347]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/usr/lib/libthread_db.so.1".
0x00007f2bb63dcfc4 in ?? () from /usr/lib/libQt5Gui.so.5
(gdb) bt
#0  0x00007f2bb63dcfc4 in  () at /usr/lib/libQt5Gui.so.5
(gdb)