> marshalの内部ですね．デバッガによるバックトレースは取れますか？ ま
た，
  > sizeof(int),sizeof(long),sizeof(void*)が知りたいのですが，調べられ
ま
  > すか？

最初からつけとくべきすね。お手数をおかけします。これで分りますでしょう
か。

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marshal
[1, 2, 3, [4, 5, "foo"], {1=>"bar"}, 2.5, 
265252859812191058636308480000000]

Program received signal 11, Segmentation fault
Reading in symbols for marshal.c...done.
0x804d587 in r_bytes0 (sp=0x80474d4, s=0x80474c4 "", len=0, arg=0x3)
    at marshal.c:532
(gdb) bt
Searching...
>0  F   0x804d587 in r_bytes0 (sp=0x80474d4, s=0x80474c4 "", len=0, arg=0x3)
    at marshal.c:532
#1  F   0x804d695 in r_string (arg=0x8047628) at marshal.c:575
#2  F   0x804d8d9 in r_object (arg=0x8047628) at marshal.c:670
#3  F   0x804d96e in r_object (arg=0x8047628) at marshal.c:686
#4  F   0x804d96e in r_object (arg=0x8047628) at marshal.c:686
#5  F   0x804dccc in load (arg=0x8047628) at marshal.c:791
#6  FI  0x80797a1 in rb_ensure (b_proc=0x804dcc0 <load>, data1=
134510120, 
    e_proc=0x804dcd0 <load_ensure>, data2=134510120) at eval.c:3191
#7  F   0x804de11 in marshal_load (argc=1, argv=0x8047754) at marshal.
c:841
#8  FI  0x8079bcc in rb_call0 (klass=135096780, recv=135096860, id=
7945, argc=1, 
    argv=0x8047754, body=0x80d6968, nosuper=1) at eval.c:3373
#9  F   0x807a6ba in rb_call (klass=135096780, recv=135096860, mid=
7945, argc=1, 
    argv=0x8047754, scope=0) at eval.c:3649
#10 F   0x8076ae4 in rb_eval (self=135144240, node=0x80b8238) at eval.
c:1981
#11 F   0x8076baa in rb_eval (self=135144240, node=0x80b8210) at eval.
c:1991
#12 F   0x8075beb in rb_eval (self=135144240, node=0x80b81e8) at eval.
c:1608
#13 F   0x8074aaf in eval_node (self=135144240) at eval.c:925
#14 F   0x8074b55 in ruby_run () at eval.c:955
#15 F   0x804a5cd in main (argc=2, argv=0x8047a44, envp=0x8047a50) at 
main.c:32
#16     0x804a597 in _start ()
(gdb) p sizeof(int)
$1 = 4
(gdb) p sizeof(long)
$2 = 4
(gdb) p sizeof(void *)
$3 = 4
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