This happened after I pressed ^C:
#0 __pthread_kill_implementation (threadid=<optimized out>,
signo=signo@entry=6, no_tid=no_tid@entry=0) at ./nptl/pthread_kill.c:44
Download failed: Invalid argument. Continuing without source file ./nptl/./nptl/pthread_kill.c.
44 ./nptl/pthread_kill.c: No such file or directory.
[Current thread is 1 (Thread 0x7f04feaf0480 (LWP 1416976))]
(gdb) where
#0 __pthread_kill_implementation (threadid=<optimized out>,
signo=signo@entry=6, no_tid=no_tid@entry=0) at ./nptl/pthread_kill.c:44
#1 0x00007f04ffaa815f in __pthread_kill_internal (signo=6,
threadid=<optimized out>) at ./nptl/pthread_kill.c:78
#2 0x00007f04ffa5a472 in __GI_raise (sig=sig@entry=6)
at ../sysdeps/posix/raise.c:26
#3 0x00007f04ffa444b2 in __GI_abort () at ./stdlib/abort.c:79
#4 0x00007f04fffc9355 in isc_assertion_failed (
file=file@entry=0x7f0500008129 "signal.c", line=line@entry=78,
type=type@entry=isc_assertiontype_require,
cond=cond@entry=0x7f0500001480 "((signal) != ((void *)0) && ((const isc__magic_t *)(signal))->magic == ((('S') << 24 | ('I') << 16 | ('G') << 8 | (' '))))") at ./lib/isc/assertions.c:49
#5 0x00007f04fffe8521 in isc_signal_stop (signal=<optimized out>)
at ./lib/isc/signal.c:78
#6 0x00007f04fffdd89e in isc_loopmgr_blocking (loopmgr=0x7f04fc208600)
at ./lib/isc/loop.c:587
#7 0x00005624a7a1b056 in get_address (host=0x7f04fc272a00 "127.0.0.1",
myport=53, sockaddr=0x7f04fc29f7d8) at ./bin/dig/dighost.c:4521
#8 0x00005624a7a1d31d in start_udp (query=<optimized out>)
at ./bin/dig/dighost.c:3263
#9 0x00005624a7a1e8ef in clear_current_lookup () at ./bin/dig/dighost.c:1820
#10 0x00005624a7a2028a in recv_done (handle=0x7f04fc29fa80,
eresult=<optimized out>, region=0x7fffab553870, arg=0x7f04fc29f700)
--Type <RET> for more, q to quit, c to continue without paging--c
at ./bin/dig/dighost.c:3915
#11 0x00007f04fffbadfc in isc___nm_readcb (arg=<optimized out>)
at netmgr/netmgr.c:1783
#12 isc__nm_readcb (sock=sock@entry=0x7f04fc274800, uvreq=<optimized out>,
eresult=eresult@entry=ISC_R_SHUTTINGDOWN, async=async@entry=false)
at netmgr/netmgr.c:1798
#13 0x00007f04fffc8146 in isc__nm_udp_failed_read_cb (sock=0x7f04fc274800,
result=ISC_R_SHUTTINGDOWN, async=false) at netmgr/udp.c:865
#14 0x00007f04ffef767b in uv_walk (loop=loop@entry=0x7f04fc272020,
walk_cb=walk_cb@entry=0x7f04fffb8b10 <shutdown_walk_cb>, arg=arg@entry=0x0)
at ./src/uv-common.c:549
#15 0x00007f04fffbb758 in networker_teardown (arg=0x7f04fc20f2f0)
at netmgr/netmgr.c:140
#16 0x00007f04fffc96a7 in isc__async_cb (handle=<optimized out>)
at ./lib/isc/async.c:111
#17 0x00007f04ffef8633 in uv__async_io (loop=0x7f04fc272020,
w=<optimized out>, events=<optimized out>) at ./src/unix/async.c:176
#18 0x00007f04fff0c065 in uv__io_poll (loop=loop@entry=0x7f04fc272020,
timeout=<optimized out>) at ./src/unix/linux.c:1476
#19 0x00007f04ffef92f8 in uv_run (loop=loop@entry=0x7f04fc272020,
mode=mode@entry=UV_RUN_DEFAULT) at ./src/unix/core.c:447
#20 0x00007f04fffdbd30 in loop_thread (arg=0x7f04fc272000)
at ./lib/isc/loop.c:282
#21 0x00005624a7a14fc8 in main (argc=2, argv=0x7fffab557dd8)
at ./bin/dig/host.c:914
(gdb)