Package: emacs;
Reported by: Spencer Baugh <sbaugh <at> janestreet.com>
Date: Tue, 26 Aug 2025 16:21:02 UTC
Severity: normal
Found in version 31.1.90
Message #5 received at submit <at> debbugs.gnu.org (full text, mbox):
From: Spencer Baugh <sbaugh <at> janestreet.com> To: bug-gnu-emacs <at> gnu.org Subject: 31.1.90; Threads + receiving a signal causes a segfault Date: Tue, 26 Aug 2025 12:19:07 -0400
repro.el:
(make-thread
(lambda ()
(sleep-for .1)
(signal-process (emacs-pid) 'sigint)))
(sleep-for 100)
emacs -Q -l ./repro.el
Observe Emacs crashes with a segfault while shutting down.
In gdb, the segfault appears to be because current_thread is NULL.
This happens both in 30.2 and on trunk.
bt full:
#0 0x000000000041f32c in Fkill_emacs (arg=arg <at> entry=make_fixnum(2), restart=restart <at> entry=XIL(0)) at emacs.c:3002
exit_code = <optimized out>
#1 0x000000000041f482 in terminate_due_to_signal (sig=sig <at> entry=2, backtrace_limit=backtrace_limit <at> entry=40) at lisp.h:1226
#2 0x000000000041f8f6 in handle_fatal_signal (sig=sig <at> entry=2) at sysdep.c:1800
#3 0x0000000000557804 in deliver_process_signal (sig=2, handler=0x41f8eb <handle_fatal_signal>) at sysdep.c:1758
old_errno = 4
on_main_thread = true
#4 0x00007fffefc12970 in <signal handler called> () at /lib64/libpthread.so.0
#5 0x00007fffec134cd9 in pselect () at /lib64/libc.so.6
#6 0x000000000063b1b0 in really_call_select (arg=0x7fffffffbb80) at thread.c:624
sa = 0x7fffffffbb80
self = 0xc77300 <main_thread>
oldset = {
__val = {0, 5631674, 1184, 0, 0, 6023007, 6, 5944137, 0, 5635264, 140736988778981, 8, 140737488337912, 13783008, 140737340983936, 6}
}
#7 0x000000000063bd7e in flush_stack_call_func (arg=0x7fffffffbb80, func=0x63b160 <really_call_select>) at lisp.h:4509
sa = {
func = 0x419450 <pselect <at> plt>,
max_fds = 6,
rfds = 0x7fffffffbc70,
wfds = 0x7fffffffbcf0,
efds = 0x0,
timeout = 0x7fffffffc280,
sigmask = 0x0,
result = -135497884
}
#8 0x000000000063bd7e in thread_select (func=<optimized out>, max_fds=max_fds <at> entry=6, rfds=rfds <at> entry=0x7fffffffbc70, wfds=wfds <at> entry=0x7fffffffbcf0, efds=efds <at> entry=0x0, timeout=timeout <at> entry=0x7fffffffc280, sigmask=0x0) at thread.c:656
sa = {
func = 0x419450 <pselect <at> plt>,
max_fds = 6,
rfds = 0x7fffffffbc70,
wfds = 0x7fffffffbcf0,
efds = 0x0,
timeout = 0x7fffffffc280,
sigmask = 0x0,
result = -135497884
}
#9 0x0000000000668a3e in xg_select (fds_lim=6, rfds=rfds <at> entry=0x7fffffffc3f0, wfds=wfds <at> entry=0x7fffffffc470, efds=efds <at> entry=0x0, timeout=timeout <at> entry=0x7fffffffc280, sigmask=sigmask <at> entry=0x0) at xgselect.c:184
all_rfds = {
fds_bits = {32, 0 <repeats 15 times>}
}
all_wfds = {
fds_bits = {0 <repeats 16 times>}
}
tmo = {
tv_sec = 0,
tv_nsec = 0
}
tmop = 0x7fffffffc280
context = 0xdb81a0
have_wfds = <optimized out>
gfds_buf = {{
fd = 5,
events = 1,
revents = 0
}, {
fd = 15393381,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 48,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 6,
events = 0,
revents = 0
}, {
fd = 2,
events = 0,
revents = 0
}, {
fd = 2,
events = 0,
revents = 0
}, {
fd = 2,
events = 0,
revents = 0
}, {
fd = 2,
events = 0,
revents = 0
}, {
fd = -334913767,
events = 32767,
revents = 0
}, {
fd = 15040436,
events = 0,
revents = 0
}, {
fd = -331543520,
events = 32767,
revents = 0
}, {
fd = 6400,
events = 0,
revents = 0
}, {
fd = 1,
events = 0,
revents = 0
}, {
fd = 7,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = -1089891930,
events = 65152,
revents = 22775
}, {
fd = 13945992,
events = 0,
revents = 0
}, {
fd = 6448,
events = 0,
revents = 0
}, {
fd = -440,
events = 65535,
revents = 65535
}, {
fd = 100,
events = 0,
revents = 0
}, {
fd = 103,
events = 148,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 103,
events = 119,
revents = 0
}, {
fd = 12,
events = 0,
revents = 0
}, {
fd = 1,
events = 0,
revents = 0
}, {
fd = 124,
events = 111,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = -331543616,
events = 32767,
revents = 0
}, {
fd = 6400,
events = 0,
revents = 0
}, {
fd = -440,
events = 65535,
revents = 65535
}, {
fd = 25,
events = 0,
revents = 0
}, {
fd = 80,
events = 0,
revents = 0
}, {
fd = 25,
events = 0,
revents = 0
}, {
fd = -334909086,
events = 32767,
revents = 0
}, {
fd = 6400,
events = 0,
revents = 0
}, {
fd = 6400,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 5873064,
events = 0,
revents = 0
}, {
fd = 3840,
events = 0,
revents = 0
}, {
fd = 0,
events = 24,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 25,
events = 0,
revents = 0
}, {
fd = 15398112,
events = 0,
revents = 0
}, {
fd = 5873287,
events = 0,
revents = 0
}, {
fd = 3840,
events = 0,
revents = 0
}, {
fd = 15398096,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 4357902,
events = 0,
revents = 0
}, {
fd = 15397616,
events = 0,
revents = 0
}, {
fd = 321,
events = 0,
revents = 0
}, {
fd = 15397600,
events = 0,
revents = 0
}, {
fd = 25,
events = 0,
revents = 0
}, {
fd = 336,
events = 0,
revents = 0
}, {
fd = -334906405,
events = 32767,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = -331543616,
events = 32767,
revents = 0
}, {
fd = -511466344,
events = 25,
revents = 0
}, {
fd = 321,
events = 0,
revents = 0
}, {
fd = 321,
events = 0,
revents = 0
}, {
fd = 1,
events = 0,
revents = 0
}, {
fd = 25,
events = 0,
revents = 0
}, {
fd = 80,
events = 0,
revents = 0
}, {
fd = 1,
events = 0,
revents = 0
}, {
fd = 5872976,
events = 0,
revents = 0
}, {
fd = 80,
events = 25,
revents = 0
}, {
fd = 1,
events = 0,
revents = 0
}, {
fd = 25,
events = 0,
revents = 0
}, {
fd = 14523552,
events = 0,
revents = 0
}, {
fd = 80,
events = 25,
revents = 0
}, {
fd = 4381164,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 4830954,
events = 0,
revents = 0
}, {
fd = 15393376,
events = 0,
revents = 0
}, {
fd = 15393376,
events = 2,
revents = 0
}, {
fd = -16220,
events = 32767,
revents = 0
}, {
fd = 15393376,
events = 0,
revents = 0
}, {
fd = 80,
events = 0,
revents = 0
}, {
fd = 80,
events = 0,
revents = 0
}, {
fd = 25,
events = 0,
revents = 0
}, {
fd = 14523552,
events = 0,
revents = 0
}, {
fd = 80,
events = 0,
revents = 0
}, {
fd = 4409751,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 5,
events = 0,
revents = 0
}, {
fd = 2,
events = 0,
revents = 0
}, {
fd = 538976288,
events = 80,
revents = 0
}, {
fd = 25,
events = 80,
revents = 0
}, {
fd = 2,
events = 8224,
revents = 8224
}, {
fd = 24,
events = 0,
revents = 0
}, {
fd = 1,
events = 25,
revents = 0
}, {
fd = 80,
events = 1,
revents = 0
}, {
fd = 80,
events = 0,
revents = 256
}, {
fd = 0,
events = 80,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 25,
events = 25,
revents = 0
}, {
fd = 6457486,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 1,
events = 0,
revents = 0
}, {
fd = 1,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 1,
events = 0,
revents = 0
}, {
fd = 5510312,
events = 0,
revents = 0
}, {
fd = -16048,
events = 32767,
revents = 0
}, {
fd = 13783008,
events = 65533,
revents = 65535
}, {
fd = -512860104,
events = 32767,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 37392,
events = 0,
revents = 0
}, {
fd = 14523557,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 5,
events = 5,
revents = 0
}, {
fd = 37392,
events = 0,
revents = 0
}, {
fd = 14523557,
events = 0,
revents = 0
}, {
fd = 48,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 1,
events = 0,
revents = 0
}, {
fd = 1,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 1,
events = 0,
revents = 0
}, {
fd = -15984,
events = 32767,
revents = 0
}, {
fd = -334485062,
events = 32767,
revents = 0
}}
gfds = 0x7fffffffbd70
gfds_size = <optimized out>
n_gfds = <optimized out>
retval = 0
our_fds = 0
max_fds = <optimized out>
i = <optimized out>
nfds = <optimized out>
tmo_in_millisec = -1
must_free = <optimized out>
need_to_dispatch = <optimized out>
#10 0x00000000006191a3 in wait_reading_process_output (time_limit=time_limit <at> entry=100, nsecs=nsecs <at> entry=0, read_kbd=read_kbd <at> entry=0, do_display=do_display <at> entry=false, wait_for_cell=wait_for_cell <at> entry=XIL(0), wait_proc=wait_proc <at> entry=0x0, just_wait_proc=0) at process.c:5711
tls_nfds = 0
tls_available = {
fds_bits = {0 <repeats 16 times>}
}
process_skipped = <optimized out>
wrapped = <optimized out>
channel_start = <optimized out>
child_fd = <optimized out>
last_read_channel = -1
channel = <optimized out>
nfds = <optimized out>
Available = {
fds_bits = {0 <repeats 16 times>}
}
Writeok = {
fds_bits = {0 <repeats 16 times>}
}
check_write = true
check_delay = <optimized out>
no_avail = false
xerrno = 4
proc = <optimized out>
timeout = {
tv_sec = 99,
tv_nsec = 999925830
}
end_time = <optimized out>
timer_delay = <optimized out>
got_output_end_time = {
tv_sec = 0,
tv_nsec = -1
}
wait = TIMEOUT
got_some_output = -1
prev_wait_proc_nbytes_read = 0
retry_for_async = <optimized out>
now = <optimized out>
#11 0x000000000042788b in Fsleep_for (seconds=<optimized out>, milliseconds=<optimized out>) at lisp.h:1192
t = {
tv_sec = 100,
tv_nsec = 0
}
tend = {
tv_sec = 1756225164,
tv_nsec = 695603177
}
duration = <optimized out>
#12 0x00000000005c1f2e in eval_sub (form=<optimized out>) at lisp.h:2243
i = <optimized out>
maxargs = 2
args_left = XIL(0)
numargs = 1
original_fun = <optimized out>
original_args = XIL(0x7ffff73ae593)
count = {
bytes = 1024
}
fun = <optimized out>
val = <optimized out>
funcar = <optimized out>
argvals = {make_fixnum(100), XIL(0), XIL(0x7fffffffc748), XIL(0x400), make_fixnum(0), XIL(0x400), make_fixnum(0), XIL(0x7fffffffc750)}
#13 0x00000000005ea19a in readevalloop_eager_expand_eval (val=<optimized out>, macroexpand=XIL(0xb340)) at lisp.h:1192
#14 0x00000000005f0dbf in readevalloop (readcharfun=XIL(0xe57515), infile0=0x0, sourcename=XIL(0xe213f4), printflag=false, unibyte=<optimized out>, readfun=XIL(0), start=XIL(0), end=XIL(0)) at lread.c:2548
c = <optimized out>
val = XIL(0x7ffff73ae583)
b = <optimized out>
continue_reading_p = true
lex_bound = <optimized out>
whole_buffer = true
first_sexp = <optimized out>
macroexpand = XIL(0xb340)
#15 0x00000000005f2070 in Feval_buffer (buffer=<optimized out>, printflag=XIL(0), filename=XIL(0xe213f4), unibyte=XIL(0), do_allow_print=<optimized out>) at lisp.h:1488
tem = XIL(0)
buf = XIL(0xe57515)
#16 0x00007ffff5f1a59e in F6c6f61642d776974682d636f64652d636f6e76657273696f6e_load_with_code_conversion_0 () at /usr/local/home/sbaugh/src/emacs/emacs-30/src/../native-lisp/30.1.90-04e012b0/preloaded/mule-0685467c-3b823856.eln
#17 0x00000000005beba0 in Ffuncall (nargs=nargs <at> entry=5, args=args <at> entry=0x7fffffffcaa0) at eval.c:3097
val = <optimized out>
#18 0x00000000005f1879 in Fload (file=XIL(0xe210a4), noerror=XIL(0), nomessage=XIL(0x30), nosuffix=<optimized out>, must_suffix=<optimized out>) at lisp.h:1488
val = <optimized out>
stream = 0x0
fd = 5
found = XIL(0xe213f4)
efound = <optimized out>
hist_file_name = <optimized out>
newer = false
compiled = false
handler = <optimized out>
fmode = 0x6b41e7 "r"
version = 0
no_native = false
is_module = false
is_native_elisp = false
found_eff = <optimized out>
is_elc = false
input = {
stream = 0xeed314,
lookahead = -92 '\244',
buf = "\020\342\000"
}
#19 0x00007ffff57d56bc in F636f6d6d616e642d6c696e652d31_command_line_1_0 () at /usr/local/home/sbaugh/src/emacs/emacs-30/src/../native-lisp/30.1.90-04e012b0/preloaded/startup-1d646357-21c0c8b9.eln
#20 0x00000000005beba0 in Ffuncall (nargs=2, args=0x7fffffffd080) at eval.c:3097
val = <optimized out>
#21 0x00007ffff57cd3af in F636f6d6d616e642d6c696e65_command_line_0 () at /usr/local/home/sbaugh/src/emacs/emacs-30/src/../native-lisp/30.1.90-04e012b0/preloaded/startup-1d646357-21c0c8b9.eln
#22 0x00000000005beba0 in Ffuncall (nargs=1, args=0x7fffffffd158) at eval.c:3097
val = <optimized out>
#23 0x00007ffff57c8bfb in F6e6f726d616c2d746f702d6c6576656c_normal_top_level_0 () at /usr/local/home/sbaugh/src/emacs/emacs-30/src/../native-lisp/30.1.90-04e012b0/preloaded/startup-1d646357-21c0c8b9.eln
#24 0x00000000005c2012 in eval_sub (form=<optimized out>) at lisp.h:2243
i = 0
maxargs = <optimized out>
args_left = XIL(0)
numargs = 0
original_fun = <optimized out>
original_args = XIL(0)
count = {
bytes = 128
}
fun = <optimized out>
val = <optimized out>
funcar = <optimized out>
argvals = {XIL(0xffffffffffffffff), XIL(0x7fffffffd3b4), XIL(0x7fffffffd3e8), make_fixnum(35184288361560), XIL(0xc77300), XIL(0xe1bb40), XIL(0x7ffff73deb43), make_fixnum(1504411)}
#25 0x00000000005c3b0f in Feval (form=XIL(0x7fffe210eaa3), lexical=lexical <at> entry=XIL(0x30)) at eval.c:2466
#26 0x0000000000537edb in top_level_2 () at lisp.h:1192
res = <optimized out>
#27 0x00000000005bd532 in internal_condition_case (bfun=bfun <at> entry=0x537e90 <top_level_2>, handlers=handlers <at> entry=XIL(0x90), hfun=hfun <at> entry=0x53f140 <cmd_error>) at eval.c:1617
val = <optimized out>
c = 0xe1bb40
#28 0x0000000000539a02 in top_level_1 (ignore=ignore <at> entry=XIL(0)) at lisp.h:1192
#29 0x00000000005bd461 in internal_catch (tag=tag <at> entry=XIL(0x122d0), func=func <at> entry=0x5399e0 <top_level_1>, arg=arg <at> entry=XIL(0)) at eval.c:1296
val = <optimized out>
c = 0xef0e00
#30 0x0000000000537dbb in command_loop () at lisp.h:1192
#31 0x000000000053ecf6 in recursive_edit_1 () at keyboard.c:754
val = <optimized out>
#32 0x000000000053f084 in Frecursive_edit () at keyboard.c:837
buffer = <optimized out>
#33 0x00000000004267a7 in main (argc=<optimized out>, argv=<optimized out>) at emacs.c:2646
stack_bottom_variable = 0xc4acf64ff28ad800
old_argc = <optimized out>
no_loadup = false
junk = 0x0
dname_arg = 0x0
ch_to_dir = 0x0
original_pwd = <optimized out>
dump_mode = <optimized out>
skip_args = 1
temacs = 0x0
attempt_load_pdump = <optimized out>
only_version = <optimized out>
rlim = {
rlim_cur = 10022912,
rlim_max = 18446744073709551615
}
lc_all = <optimized out>
sockfd = -1
module_assertions = <optimized out>
In GNU Emacs 30.1.90 (build 9, x86_64-pc-linux-gnu, X toolkit, cairo
version 1.15.12, Xaw scroll bars) of 2025-08-14 built on
igm-qws-u22796a
Repository revision: 6adc26ffa74aedbd1cfa9a1ee72073ebccea2b96
Repository branch: emacs-30
Windowing system distributor 'The X.Org Foundation', version 11.0.12101016
System Description: Rocky Linux 8.10 (Green Obsidian)
Configured using:
'configure --with-x-toolkit=lucid --without-gpm --without-gconf
--without-selinux --without-imagemagick --with-modules --with-gif=no
--with-cairo --with-rsvg --without-compress-install --with-tree-sitter
--with-native-compilation=aot
PKG_CONFIG_PATH=/usr/local/home/garnish/libtree-sitter/0.22.6-1/lib/pkgconfig/'
Configured features:
CAIRO DBUS FREETYPE GLIB GMP GNUTLS GSETTINGS HARFBUZZ JPEG LIBSYSTEMD
LIBXML2 MODULES NATIVE_COMP NOTIFY INOTIFY PDUMPER PNG RSVG SECCOMP
SOUND SQLITE3 THREADS TIFF TOOLKIT_SCROLL_BARS TREE_SITTER X11 XDBE XIM
XINPUT2 XPM LUCID ZLIB
Important settings:
value of $LANG: en_US.utf8
locale-coding-system: utf-8-unix
GNU bug tracking system
Copyright (C) 1999 Darren O. Benham,
1997,2003 nCipher Corporation Ltd,
1994-97 Ian Jackson.