ubuntu@ubuntu:~/emacs25-25.1+1.dbg/debian/build-x/admin/grammars$ gdb ../../src/emacs core 
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Reading symbols from ../../src/emacs...done.
[New LWP 24349]
[New LWP 24350]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/aarch64-linux-gnu/libthread_db.so.1".
Core was generated by `../../src/emacs -batch --no-site-file --no-site-lisp -l semantic/bovine/grammar'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0  __flockfile (stream=0x0) at ../sysdeps/pthread/flockfile.c:28
28	../sysdeps/pthread/flockfile.c: No such file or directory.
[Current thread is 1 (Thread 0xffff9da129d0 (LWP 24349))]
(gdb) set pagination off
(gdb) bt
#0  __flockfile (stream=0x0) at ../sysdeps/pthread/flockfile.c:28
#1  0x00000000004e0cc4 in terminate_due_to_signal (sig=sig@entry=11, backtrace_limit=backtrace_limit@entry=40) at emacs.c:381
#2  0x00000000004f74f8 in handle_fatal_signal (sig=sig@entry=11) at sysdep.c:1601
#3  0x00000000004f7734 in deliver_thread_signal (sig=sig@entry=11, handler=0x4f74e8 <handle_fatal_signal>) at sysdep.c:1575
#4  0x00000000004f77ac in deliver_fatal_thread_signal (sig=11) at sysdep.c:1613
#5  handle_sigsegv (sig=11, siginfo=<optimized out>, arg=<optimized out>) at sysdep.c:1695
#6  <signal handler called>
#7  unchain_marker (marker=marker@entry=0x130ad18) at marker.c:605
#8  0x00000000005334a4 in free_marker (marker=marker@entry=19967257) at alloc.c:3850
#9  0x0000000000505b98 in signal_before_change (preserve_ptr=0x0, end_int=44894, start_int=9854976) at insdel.c:2041
#10 prepare_to_modify_buffer_1 (start=start@entry=11223, end=end@entry=11223, preserve_ptr=preserve_ptr@entry=0x0) at insdel.c:1867
#11 0x0000000000506050 in prepare_to_modify_buffer (start=11223, end=11223, preserve_ptr=preserve_ptr@entry=0x0) at insdel.c:1878
#12 0x0000000000506268 in insert_1_both (string=string@entry=0xffffd674f1d8 "         ", nchars=nchars@entry=5, nbytes=nbytes@entry=5, inherit=inherit@entry=true, prepare=prepare@entry=true, before_markers=before_markers@entry=false) at insdel.c:801
#13 0x0000000000506a6c in insert_1_both (before_markers=false, prepare=true, inherit=true, nbytes=5, nchars=5, string=0xffffd674f1d8 "         ") at insdel.c:600
#14 insert_and_inherit (string=0xffffd674f1d8 "         ", nbytes=5) at insdel.c:597
#15 0x0000000000542284 in Finsert_char (character=character@entry=130, count=<optimized out>, inherit=inherit@entry=44448) at editfns.c:2641
#16 0x000000000051aba4 in Findent_to (column=<optimized out>, minimum=<optimized out>, minimum@entry=0) at indent.c:848
#17 0x00000000005802f4 in exec_byte_code (bytestr=<optimized out>, vector=<optimized out>, maxdepth=<optimized out>, args_template=<optimized out>, nargs=nargs@entry=0, args=<optimized out>, args@entry=0xffffd67502e0) at bytecode.c:1575
#18 0x000000000054cfa0 in funcall_lambda (fun=fun@entry=723107683, nargs=nargs@entry=0, arg_vector=arg_vector@entry=0xffffd67502e0) at eval.c:2855
#19 0x000000000054c2d0 in apply_lambda (fun=723107683, fun@entry=7940517, args=<optimized out>, count=4294967295, count@entry=44) at eval.c:2794
#20 0x000000000054c650 in eval_sub (form=<optimized out>) at eval.c:2241
#21 0x000000000054cb70 in Fprogn (body=723107715, body@entry=723107683) at eval.c:426
#22 0x0000000000546c44 in Fsave_excursion (args=723107683) at editfns.c:1014
#23 0x000000000054c818 in eval_sub (form=<optimized out>) at eval.c:2119
#24 0x000000000054fa30 in Fprogn (body=723107731) at eval.c:426
#25 Flet (args=9859131) at eval.c:946
#26 0x000000000054c818 in eval_sub (form=<optimized out>) at eval.c:2119
#27 0x000000000054cfcc in Fprogn (body=723107779) at eval.c:426
#28 funcall_lambda (fun=10272, fun@entry=12262675, nargs=nargs@entry=3, arg_vector=arg_vector@entry=0xffffd6750770) at eval.c:2914
#29 0x000000000054c2d0 in apply_lambda (fun=12262675, fun@entry=723105875, args=<optimized out>, count=4294967295, count@entry=36) at eval.c:2794
#30 0x000000000054c650 in eval_sub (form=<optimized out>) at eval.c:2241
#31 0x000000000054cb70 in Fprogn (body=12261011, body@entry=12262675) at eval.c:426
#32 0x0000000000546c44 in Fsave_excursion (args=12262675) at editfns.c:1014
#33 0x000000000054c818 in eval_sub (form=<optimized out>) at eval.c:2119
#34 0x000000000054cbd4 in Fprogn (body=13569939) at eval.c:426
#35 Fif (args=<optimized out>) at eval.c:384
#36 0x000000000054c818 in eval_sub (form=<optimized out>) at eval.c:2119
#37 0x000000000054f770 in Fprogn (body=13567587) at eval.c:426
#38 FletX (args=13567331) at eval.c:882
#39 0x000000000054c818 in eval_sub (form=<optimized out>) at eval.c:2119
#40 0x000000000054cfcc in Fprogn (body=13566499) at eval.c:426
#41 funcall_lambda (fun=13781520, fun@entry=723108003, nargs=nargs@entry=2, arg_vector=arg_vector@entry=0xffffd6750cc0) at eval.c:2914
#42 0x000000000054c2d0 in apply_lambda (fun=723108003, fun@entry=19998211, args=<optimized out>, count=4294967295, count@entry=20) at eval.c:2794
#43 0x000000000054c650 in eval_sub (form=<optimized out>) at eval.c:2241
#44 0x000000000054cb70 in Fprogn (body=723108067, body@entry=723108003) at eval.c:426
#45 0x00000000005417cc in Fsave_current_buffer (args=723108003) at editfns.c:1027
#46 0x000000000054c818 in eval_sub (form=form@entry=5568768) at eval.c:2119
#47 0x000000000054fe50 in internal_lisp_condition_case (var=<optimized out>, bodyform=5568768, handlers=<optimized out>) at eval.c:1280
#48 0x000000000054c818 in eval_sub (form=<optimized out>) at eval.c:2119
#49 0x000000000054f900 in Flet (args=723102451) at eval.c:918
#50 0x000000000054c818 in eval_sub (form=<optimized out>) at eval.c:2119
#51 0x000000000054cfcc in Fprogn (body=723102371) at eval.c:426
#52 funcall_lambda (fun=722114352, fun@entry=44448, nargs=nargs@entry=2, arg_vector=arg_vector@entry=0xffffd67512d0) at eval.c:2914
#53 0x000000000054c2d0 in apply_lambda (fun=44448, fun@entry=723102419, args=<optimized out>, count=9859128, count@entry=13) at eval.c:2794
#54 0x000000000054c650 in eval_sub (form=<optimized out>) at eval.c:2241
#55 0x000000000054cfcc in Fprogn (body=723132339) at eval.c:426
#56 funcall_lambda (fun=712183688, nargs=nargs@entry=0, arg_vector=arg_vector@entry=0xffffd6751608) at eval.c:2914
#57 0x000000000054d264 in Ffuncall (nargs=nargs@entry=1, args=args@entry=0xffffd6751600) at eval.c:2754
#58 0x000000000057f3a4 in exec_byte_code (bytestr=<optimized out>, vector=<optimized out>, maxdepth=<optimized out>, args_template=<optimized out>, nargs=nargs@entry=1, args=<optimized out>, args@entry=0xffffd67517b0) at bytecode.c:880
#59 0x000000000054cfa0 in funcall_lambda (fun=7575400, nargs=nargs@entry=1, arg_vector=arg_vector@entry=0xffffd67517b0) at eval.c:2855
#60 0x000000000054d264 in Ffuncall (nargs=nargs@entry=2, args=args@entry=0xffffd67517a8) at eval.c:2754
#61 0x000000000057f3a4 in exec_byte_code (bytestr=<optimized out>, vector=<optimized out>, maxdepth=<optimized out>, args_template=<optimized out>, nargs=nargs@entry=0, args=<optimized out>, args@entry=0xffffd67519b8) at bytecode.c:880
#62 0x000000000054cfa0 in funcall_lambda (fun=5769148, nargs=nargs@entry=0, arg_vector=arg_vector@entry=0xffffd67519b8) at eval.c:2855
#63 0x000000000054d264 in Ffuncall (nargs=nargs@entry=1, args=args@entry=0xffffd67519b0) at eval.c:2754
#64 0x000000000057f3a4 in exec_byte_code (bytestr=<optimized out>, vector=<optimized out>, maxdepth=<optimized out>, args_template=<optimized out>, nargs=nargs@entry=0, args=<optimized out>, args@entry=0xffffd6751ab0) at bytecode.c:880
#65 0x000000000054cfa0 in funcall_lambda (fun=fun@entry=6142712, nargs=nargs@entry=0, arg_vector=arg_vector@entry=0xffffd6751ab0) at eval.c:2855
#66 0x000000000054c2d0 in apply_lambda (fun=6142712, fun@entry=7571293, args=<optimized out>, count=6310728, count@entry=4) at eval.c:2794
#67 0x000000000054c650 in eval_sub (form=form@entry=15021379) at eval.c:2241
#68 0x000000000054ff48 in Feval (form=15021379, lexical=<optimized out>) at eval.c:1988
#69 0x000000000054bb94 in internal_condition_case (bfun=0x54bb40 <internal_catch+72>, bfun@entry=0x4e1188 <top_level_2>, handlers=handlers@entry=19056, hfun=0xffffd6751c70, hfun@entry=0x4e57c8 <cmd_error>) at eval.c:1309
#70 0x00000000004e34d0 in top_level_1 (ignore=<optimized out>) at keyboard.c:1124
#71 0x000000000054bb40 in internal_catch (tag=tag@entry=45840, func=0x4e5344 <recursive_edit_1+116>, func@entry=0x4e3468 <top_level_1>, arg=281474279742672, arg@entry=0) at eval.c:1074
#72 0x00000000004e1124 in command_loop () at keyboard.c:1085
#73 0x00000000004e5344 in recursive_edit_1 () at keyboard.c:692
#74 0x00000000004e5704 in Frecursive_edit () at keyboard.c:763
#75 0x000000000041b480 in main (argc=11, argv=<optimized out>) at emacs.c:1626
(gdb)