Here's my reproduction of this bug. I do not get any output from xbacktrace (i did source src/.gdbinit)
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(gdb) thread apply all bt
Thread 4 (Thread 0x7fe956851700 (LWP 3454)):
#0 0x00007fe95d754fdd in poll () at ../sysdeps/unix/syscall-template.S:81
#1 0x00007fe961302fe4 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2 0x00007fe9613030ec in g_main_context_iteration ()
from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3 0x00007fe961303129 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#4 0x00007fe961327f05 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#5 0x00007fe95da35184 in start_thread (arg=0x7fe956851700)
at pthread_create.c:312
#6 0x00007fe95d76237d in clone ()
at ../sysdeps/unix/sysv/linux/x86_64/clone.S:111
Thread 3 (Thread 0x7fe955819700 (LWP 3455)):
#0 0x00007fe95d754fdd in poll () at ../sysdeps/unix/syscall-template.S:81
#1 0x00007fe961302fe4 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2 0x00007fe9613030ec in g_main_context_iteration ()
from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3 0x00007fe9558211ad in ?? ()
from /usr/lib/x86_64-linux-gnu/gio/modules/libdconfsettings.so
#4 0x00007fe961327f05 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#5 0x00007fe95da35184 in start_thread (arg=0x7fe955819700)
at pthread_create.c:312
#6 0x00007fe95d76237d in clone ()
at ../sysdeps/unix/sysv/linux/x86_64/clone.S:111
Thread 2 (Thread 0x7fe94ffff700 (LWP 3456)):
#0 0x00007fe95d754fdd in poll () at ../sysdeps/unix/syscall-template.S:81
#1 0x00007fe961302fe4 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2 0x00007fe96130330a in g_main_loop_run ()
from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3 0x00007fe962063336 in ?? () from /usr/lib/x86_64-linux-gnu/libgio-2.0.so.0
#4 0x00007fe961327f05 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#5 0x00007fe95da35184 in start_thread (arg=0x7fe94ffff700)
at pthread_create.c:312
#6 0x00007fe95d76237d in clone ()
at ../sysdeps/unix/sysv/linux/x86_64/clone.S:111
Thread 1 (Thread 0x7fe963eaca80 (LWP 3453)):
#0 __GI___pthread_mutex_lock (mutex=0x13b8e00)
at ../nptl/pthread_mutex_lock.c:122
---Type <return> to continue, or q <return> to quit---
#1 0x00007fe961344981 in g_mutex_lock ()
from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2 0x00007fe961302699 in g_main_context_prepare ()
from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3 0x00007fe961302f03 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#4 0x00007fe961303097 in g_main_context_pending ()
from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#5 0x00007fe962746e9d in gtk_events_pending ()
from /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#6 0x00000000004ba4fb in XTread_socket (terminal=<optimized out>,
hold_quit=0x7fffcff83d70) at xterm.c:7011
#7 0x00000000004ecbe1 in gobble_input () at keyboard.c:6851
#8 0x00000000004ec605 in handle_async_input () at keyboard.c:7091
#9 process_pending_signals () at keyboard.c:7105
#10 0x000000000053dd42 in Fmake_list (length=<optimized out>, init=12144946)
at alloc.c:2637
#11 0x000000000055c7f8 in concat (nargs=nargs@entry=1,
args=args@entry=0x7fffcff83ee8, target_type=Lisp_Cons,
last_special=last_special@entry=false) at fns.c:588
#12 0x000000000055d321 in Fcopy_sequence (arg=19525990) at fns.c:456
#13 0x00000000004eb416 in timer_check () at keyboard.c:4572
#14 0x00000000004eb921 in readable_events (flags=1) at keyboard.c:3448
#15 0x00000000004ecce8 in get_input_pending (flags=1) at keyboard.c:6766
#16 0x00000000004f0134 in detect_input_pending_run_timers (
do_display=do_display@entry=true) at keyboard.c:9895
#17 0x0000000000595ac6 in wait_reading_process_output (
time_limit=time_limit@entry=30, nsecs=nsecs@entry=0,
read_kbd=read_kbd@entry=-1, do_display=do_display@entry=true,
wait_for_cell=12144946, wait_proc=wait_proc@entry=0x0,
just_wait_proc=just_wait_proc@entry=0) at process.c:4702
#18 0x0000000000421a74 in sit_for (timeout=<optimized out>,
reading=reading@entry=true, display_option=display_option@entry=1)
at dispnew.c:5867
#19 0x00000000004f0e54 in read_char (commandflag=1, map=map@entry=38081766,
prev_event=12144946, used_mouse_menu=used_mouse_menu@entry=0x7fffcff8472b,
end_time=end_time@entry=0x0) at keyboard.c:2810
#20 0x00000000004f232f in read_key_sequence (
keybuf=keybuf@entry=0x7fffcff84800, prompt=12144946,
dont_downcase_last=dont_downcase_last@entry=false,
can_return_switch_frame=can_return_switch_frame@entry=true,
fix_current_buffer=fix_current_buffer@entry=true,
---Type <return> to continue, or q <return> to quit---
prevent_redisplay=prevent_redisplay@entry=false, bufsize=30)
at keyboard.c:9089
#21 0x00000000004f3f20 in command_loop_1 () at keyboard.c:1453
#22 0x0000000000555b4e in internal_condition_case (
bfun=bfun@entry=0x4f3d30 <command_loop_1>, handlers=<optimized out>,
hfun=hfun@entry=0x4eaca0 <cmd_error>) at eval.c:1348
#23 0x00000000004e63de in command_loop_2 (ignore=ignore@entry=12144946)
at keyboard.c:1178
#24 0x0000000000555a5b in internal_catch (tag=12192450,
func=func@entry=0x4e63c0 <command_loop_2>, arg=12144946) at eval.c:1112
#25 0x00000000004ea8c7 in command_loop () at keyboard.c:1157
#26 recursive_edit_1 () at keyboard.c:778
#27 0x00000000004eabdd in Frecursive_edit () at keyboard.c:849
#28 0x0000000000417c95 in main (argc=<optimized out>, argv=0x7fffcff84b58)
at emacs.c:1642
(gdb) xbacktrace
(gdb)