GDB output:
Starting program: /PWD/a.out
[Thread debugging using libthread_db enabled] Using host libthread_db library "/usr/lib/libthread_db.so.1". [New Thread 0x7fffd9293700 (LWP 1744)]
Thread 1 "a.out" received signal SIGSEGV, Segmentation fault. 0x00007fffe9497370 in av_buffer_unref () from /usr/lib/libavutil.so.55
Machine:
OpenCV - version 3.2.0
ffmpeg - version 3.3
OS - Manjaro Linux