Here is the backtrace I obtained using gdb, as per the HowToGetABacktrace page on the Debian wiki:
Thread 1 "ghb" received signal SIGABRT, Aborted.
0x00007ffff371fce1 in raise () from /lib/x86_64-linux-gnu/libc.so.6
#0 0x00007ffff371fce1 in raise () at /lib/x86_64-linux-gnu/libc.so.6
#1 0x00007ffff3709537 in abort () at /lib/x86_64-linux-gnu/libc.so.6
#2 0x00007ffff370940f in () at /lib/x86_64-linux-gnu/libc.so.6
#3 0x00007ffff3718662 in () at /lib/x86_64-linux-gnu/libc.so.6
#4 0x00007fffbd09ec35 in intel_enc_hw_context_init (ctx=0x555556ae5fd0, obj_config=0x555556ae94a0, vme_context_init=0x7fffbd075020 <gen8_vme_context_init>, mfc_context_init=0x7fffbd06cf20 <gen8_mfc_context_init>) at i965_encoder.c:1692
#5 0x00007fffbd096827 in i965_CreateContext (ctx=<optimized out>, config_id=<optimized out>, picture_width=<optimized out>, picture_height=<optimized out>, flag=<optimized out>, render_targets=0x555556ae5b80, num_render_targets=<optimized out>, context=<optimized out>) at i965_drv_video.c:2706
#6 0x00007ffff3a21de4 in vaCreateContext (dpy=0x555556ae5e60, config_id=16777216, picture_width=1920, picture_height=1088, flag=1, render_targets=0x555556ae5b80, num_render_targets=4, context=0x555556afb7c0) at va.c:1239
#7 0x00007fffbe3fc02d in () at /usr/lib/x86_64-linux-gnu/libmfxhw64.so.1
#8 0x00007fffbe36b55d in () at /usr/lib/x86_64-linux-gnu/libmfxhw64.so.1
#9 0x00007fffbe36ccb6 in () at /usr/lib/x86_64-linux-gnu/libmfxhw64.so.1
#10 0x00007fffbe24fdd7 in MFXVideoENCODE_Init () at /usr/lib/x86_64-linux-gnu/libmfxhw64.so.1
#11 0x00005555555fd47b in ()
#12 0x00005555556002b4 in ()
#13 0x000055555560042f in ()
#14 0x00005555555e0945 in ()
#15 0x00005555555b9fb8 in ghb_backend_init ()
#16 0x00005555555a79a5 in ghb_activate_cb ()
#17 0x00007ffff705665f in g_closure_invoke () at /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#18 0x00007ffff706899b in () at /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#19 0x00007ffff706ec6f in g_signal_emit_valist () at /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#20 0x00007ffff706f1df in g_signal_emit () at /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#21 0x00007ffff73d0ed8 in () at /usr/lib/x86_64-linux-gnu/libgio-2.0.so.0
#22 0x00007ffff73d104e in g_application_run () at /usr/lib/x86_64-linux-gnu/libgio-2.0.so.0
#23 0x0000555555586042 in main ()
#0 0x00007ffff371fce1 in raise () at /lib/x86_64-linux-gnu/libc.so.6
#1 0x00007ffff3709537 in abort () at /lib/x86_64-linux-gnu/libc.so.6
#2 0x00007ffff370940f in () at /lib/x86_64-linux-gnu/libc.so.6
#3 0x00007ffff3718662 in () at /lib/x86_64-linux-gnu/libc.so.6
#4 0x00007fffbd09ec35 in intel_enc_hw_context_init (ctx=0x555556ae5fd0, obj_config=0x555556ae94a0, vme_context_init=0x7fffbd075020 <gen8_vme_context_init>, mfc_context_init=0x7fffbd06cf20 <gen8_mfc_context_init>) at i965_encoder.c:1692
i965 = <optimized out>
intel = <optimized out>
encoder_context = 0x555556b16670
i = <optimized out>
__PRETTY_FUNCTION__ = "intel_enc_hw_context_init"
#5 0x00007fffbd096827 in i965_CreateContext (ctx=<optimized out>, config_id=<optimized out>, picture_width=<optimized out>, picture_height=<optimized out>, flag=<optimized out>, render_targets=0x555556ae5b80, num_render_targets=<optimized out>, context=<optimized out>) at i965_drv_video.c:2706
i965 = 0x555556ae86a0
obj_config = 0x555556ae94a0
obj_context = 0x555556aea630
attrib = <optimized out>
vaStatus = 0
contextID = <optimized out>
i = <optimized out>
max_width = 4096
max_height = 4096
min_width_height = <optimized out>
__PRETTY_FUNCTION__ = "i965_CreateContext"
#6 0x00007ffff3a21de4 in vaCreateContext (dpy=0x555556ae5e60, config_id=16777216, picture_width=1920, picture_height=1088, flag=1, render_targets=0x555556ae5b80, num_render_targets=4, context=0x555556afb7c0) at va.c:1239
ctx = <optimized out>
vaStatus = <optimized out>
__func__ = "vaCreateContext"
#7 0x00007fffbe3fc02d in () at /usr/lib/x86_64-linux-gnu/libmfxhw64.so.1
#8 0x00007fffbe36b55d in () at /usr/lib/x86_64-linux-gnu/libmfxhw64.so.1
#9 0x00007fffbe36ccb6 in () at /usr/lib/x86_64-linux-gnu/libmfxhw64.so.1
#10 0x00007fffbe24fdd7 in MFXVideoENCODE_Init () at /usr/lib/x86_64-linux-gnu/libmfxhw64.so.1
#11 0x00005555555fd47b in ()
#12 0x00005555556002b4 in ()
#13 0x000055555560042f in ()
#14 0x00005555555e0945 in ()
#15 0x00005555555b9fb8 in ghb_backend_init ()
#16 0x00005555555a79a5 in ghb_activate_cb ()
#17 0x00007ffff705665f in g_closure_invoke () at /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#18 0x00007ffff706899b in () at /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#19 0x00007ffff706ec6f in g_signal_emit_valist () at /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#20 0x00007ffff706f1df in g_signal_emit () at /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#21 0x00007ffff73d0ed8 in () at /usr/lib/x86_64-linux-gnu/libgio-2.0.so.0
#22 0x00007ffff73d104e in g_application_run () at /usr/lib/x86_64-linux-gnu/libgio-2.0.so.0
#23 0x0000555555586042 in main ()