Bug 17224

testcase: forever-threads from pr 17147

@ruffy:gdb$ cat foo.gdb
set trace-commands on
show interactive-mode
set interactive-mode on
#set non-stop on
file ~/src/play/forever-threads.x64
run &
shell sleep 3
info threads
@ruffy:gdb$ ./gdb -D ./data-directory < foo.gdb
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(gdb) (gdb) +show interactive-mode
Debugger's interactive mode is auto (currently off).
(gdb) +set interactive-mode on
(gdb) (gdb) +file ~/src/play/forever-threads.x64
Reading symbols from ~/src/play/forever-threads.x64...done.
(gdb) +run &
Starting program: /home/dje/src/play/forever-threads.x64
Segmentation fault

Backtrace:

(top-gdb) bt
#0  0x00000000004bfc4c in hardwire_copy_tty_state (scb=0xecabe0, ttystate=0x0) at ../../experiment/gdb/ser-unix.c:200
#1  0x0000000000729401 in serial_copy_tty_state (scb=0xecabe0, ttystate=0x0) at ../../experiment/gdb/serial.c:491
#2  0x000000000077dc26 in child_terminal_init_with_pgrp (pgrp=21249) at ../../experiment/gdb/inflow.c:231
#3  0x000000000077dcb1 in child_terminal_init (self=0xd65100) at ../../experiment/gdb/inflow.c:265
#4  0x0000000000651daa in delegate_terminal_init (self=0xd65100) at ../../experiment/gdb/target-delegates.c:731
#5  0x00000000004c2fc3 in startup_inferior (ntraps=1) at ../../experiment/gdb/fork-child.c:512
#6  0x00000000004c13f4 in inf_ptrace_create_inferior (ops=0xd65100, exec_file=0x1022840 "/home/dje/src/play/forever-threads.x64", allargs=0x1052620 "", env=0xec\
76a0, from_tty=1) at ../../experiment/gdb/inf-ptrace.c:140
#7  0x00000000004c7ff9 in linux_nat_create_inferior (ops=0xd65100, exec_file=0x1022840 "/home/dje/src/play/forever-threads.x64", allargs=0x1052620 "", env=0xec7\
6a0, from_tty=1) at ../../experiment/gdb/linux-nat.c:1318
#8  0x0000000000601a89 in run_command_1 (args=0x0, from_tty=1, tbreak_at_main=0) at ../../experiment/gdb/infcmd.c:605
#9  0x0000000000601b8e in run_command (args=0xcdcdb4 "&", from_tty=1) at ../../experiment/gdb/infcmd.c:640
#10 0x000000000050c526 in do_cfunc (c=0xd9a180, args=0xcdcdb4 "&", from_tty=1) at ../../experiment/gdb/cli/cli-decode.c:107
#11 0x000000000050f613 in cmd_func (cmd=0xd9a180, args=0xcdcdb4 "&", from_tty=1) at ../../experiment/gdb/cli/cli-decode.c:1885
#12 0x00000000007354a2 in execute_command (p=0xcdcdb4 "&", from_tty=1) at ../../experiment/gdb/top.c:462
#13 0x000000000062d325 in command_handler (command=0xcdcdb0 "") at ../../experiment/gdb/event-top.c:433
#14 0x000000000062d8de in command_line_handler (rl=0x1054f20 "") at ../../experiment/gdb/event-top.c:630
#15 0x000000000062da65 in gdb_readline2 (client_data=0x0) at ../../experiment/gdb/event-top.c:711
#16 0x000000000062d237 in stdin_event_handler (error=0, client_data=0x0) at ../../experiment/gdb/event-top.c:373
#17 0x000000000062be2c in handle_file_event (data=...) at ../../experiment/gdb/event-loop.c:766
#18 0x000000000062b313 in process_event () at ../../experiment/gdb/event-loop.c:343
#19 0x000000000062b3b5 in gdb_do_one_event () at ../../experiment/gdb/event-loop.c:395
#20 0x000000000062b42a in start_event_loop () at ../../experiment/gdb/event-loop.c:432
#21 0x000000000062ce93 in cli_command_loop (data=0x0) at ../../experiment/gdb/event-top.c:182
#22 0x0000000000623853 in current_interp_command_loop () at ../../experiment/gdb/interps.c:328
#23 0x000000000062438d in captured_command_loop (data=0x0) at ../../experiment/gdb/main.c:324
#24 0x00000000006206e1 in catch_errors (func=0x624372 <captured_command_loop>, func_args=0x0, errstring=0x9feb4d "", mask=RETURN_MASK_ALL) at ../../experiment/g\
db/exceptions.c:516
#25 0x00000000006258dc in captured_main (data=0x7fffffffe680) at ../../experiment/gdb/main.c:1180
#26 0x00000000006206e1 in catch_errors (func=0x624769 <captured_main>, func_args=0x7fffffffe680, errstring=0x9feb4d "", mask=RETURN_MASK_ALL) at ../../experimen\
t/gdb/exceptions.c:516
#27 0x0000000000625905 in gdb_main (args=0x7fffffffe680) at ../../experiment/gdb/main.c:1188
#28 0x00000000004737b7 in main (argc=3, argv=0x7fffffffe788) at ../../experiment/gdb/gdb.c:33