(gdb) run 11111111111111111111111111111
Starting program: /home/ubuntuvm/stack_overflow/so_ans 11111111111111111111111111111

Breakpoint 1, main (argc=2, argv=0x7fffffffdfe8) at ans_check.c:25
25	  if (check_answer(argv[1])) {
(gdb) i r rsp
rsp            0x7fffffffdef0	0x7fffffffdef0
(gdb) x/32xw $rsp
0x7fffffffdef0:	0xffffdfe8	0x00007fff	0x00000000	0x00000002
0x7fffffffdf00:	0x00000000	0x00000000	0xf7a32f45	0x00007fff
0x7fffffffdf10:	0x00000000	0x00000000	0xffffdfe8	0x00007fff
0x7fffffffdf20:	0x00000000	0x00000002	0x00400694	0x00000000
0x7fffffffdf30:	0x00000000	0x00000000	0x6343254b	0x86411a5f
0x7fffffffdf40:	0x00400560	0x00000000	0xffffdfe0	0x00007fff
0x7fffffffdf50:	0x00000000	0x00000000	0x00000000	0x00000000
0x7fffffffdf60:	0xdd63254b	0x79bee5a0	0x3eb9254b	0x79bef519
(gdb) c
Continuing.

Breakpoint 2, check_answer (ans=0x7fffffffe367 '1' <repeats 29 times>)
    at ans_check.c:10
10	  strcpy(ans_buf, ans);
(gdb) i r rsp
rsp            0x7fffffffdeb0	0x7fffffffdeb0
(gdb) x/32xw $rsp
0x7fffffffdeb0:	0xf7ffe1c8	0x00007fff	0xffffe367	0x00007fff
0x7fffffffdec0:	0x00000001	0x00000000	0x0040074d	0x00000000
0x7fffffffded0:	0xffffdf00	0x00007fff	0x00000000	0x00000000
0x7fffffffdee0:	0xffffdf00	0x00007fff	0x004006df	0x00000000
0x7fffffffdef0:	0xffffdfe8	0x00007fff	0x00000000	0x00000002
0x7fffffffdf00:	0x00000000	0x00000000	0xf7a32f45	0x00007fff
0x7fffffffdf10:	0x00000000	0x00000000	0xffffdfe8	0x00007fff
0x7fffffffdf20:	0x00000000	0x00000002	0x00400694	0x00000000
(gdb) x/s ans_buf
0x7fffffffdec0:	"\001"
(gdb) x/s &ans_flag
0x7fffffffdedc:	""
(gdb) c
Continuing.

Breakpoint 3, check_answer (ans=0x7fffffffe367 '1' <repeats 29 times>)
    at ans_check.c:15
15	  return ans_flag;
(gdb) i r rsp
rsp            0x7fffffffdeb0	0x7fffffffdeb0
(gdb) x/32xw $rsp
0x7fffffffdeb0:	0xf7ffe1c8	0x00007fff	0xffffe367	0x00007fff
0x7fffffffdec0:	0x31313131	0x31313131	0x31313131	0x31313131
0x7fffffffded0:	0x31313131	0x31313131	0x31313131	0x00000031
0x7fffffffdee0:	0xffffdf00	0x00007fff	0x004006df	0x00000000
0x7fffffffdef0:	0xffffdfe8	0x00007fff	0x00000000	0x00000002
0x7fffffffdf00:	0x00000000	0x00000000	0xf7a32f45	0x00007fff
0x7fffffffdf10:	0x00000000	0x00000000	0xffffdfe8	0x00007fff
0x7fffffffdf20:	0x00000000	0x00000002	0x00400694	0x00000000
(gdb)