Hi,
I am trying to understand where are unnamed string constants are
defined in symbol tables.
In the following example, the unnamed string constant is "Hello World!".
$ cat a.c
#include <stdio.h>
int main() { puts("Hello World!"); }
$ gcc -c a.c
$ gcc -o a.out a.o
But I don't find it in the symbol table. Could anybody point to me
where it is? Thanks.
$ readelf -s a.o
Symbol table '.symtab' contains 12 entries:
Num: Value Size Type Bind Vis Ndx Name
0: 0000000000000000 0 NOTYPE LOCAL DEFAULT UND
1: 0000000000000000 0 FILE LOCAL DEFAULT ABS a.c
2: 0000000000000000 0 SECTION LOCAL DEFAULT 1
3: 0000000000000000 0 SECTION LOCAL DEFAULT 3
4: 0000000000000000 0 SECTION LOCAL DEFAULT 4
5: 0000000000000000 0 SECTION LOCAL DEFAULT 5
6: 0000000000000000 0 SECTION LOCAL DEFAULT 7
7: 0000000000000000 0 SECTION LOCAL DEFAULT 8
8: 0000000000000000 0 SECTION LOCAL DEFAULT 6
9: 0000000000000000 23 FUNC GLOBAL DEFAULT 1 main
10: 0000000000000000 0 NOTYPE GLOBAL DEFAULT UND _GLOBAL_OFFSET_TABLE_
11: 0000000000000000 0 NOTYPE GLOBAL DEFAULT UND puts
$ readelf -s a.out
Symbol table '.dynsym' contains 7 entries:
Num: Value Size Type Bind Vis Ndx Name
0: 0000000000000000 0 NOTYPE LOCAL DEFAULT UND
1: 0000000000000000 0 NOTYPE WEAK DEFAULT UND _ITM_deregisterT[...]
2: 0000000000000000 0 FUNC GLOBAL DEFAULT UND puts@GLIBC_2.2.5 (2)
3: 0000000000000000 0 FUNC GLOBAL DEFAULT UND [...]@GLIBC_2.2.5 (2)
4: 0000000000000000 0 NOTYPE WEAK DEFAULT UND __gmon_start__
5: 0000000000000000 0 NOTYPE WEAK DEFAULT UND _ITM_registerTMC[...]
6: 0000000000000000 0 FUNC WEAK DEFAULT UND [...]@GLIBC_2.2.5 (2)
Symbol table '.symtab' contains 64 entries:
Num: Value Size Type Bind Vis Ndx Name
0: 0000000000000000 0 NOTYPE LOCAL DEFAULT UND
1: 00000000000002a8 0 SECTION LOCAL DEFAULT 1
2: 00000000000002c4 0 SECTION LOCAL DEFAULT 2
3: 00000000000002e8 0 SECTION LOCAL DEFAULT 3
4: 0000000000000308 0 SECTION LOCAL DEFAULT 4
5: 0000000000000330 0 SECTION LOCAL DEFAULT 5
6: 00000000000003d8 0 SECTION LOCAL DEFAULT 6
7: 000000000000045a 0 SECTION LOCAL DEFAULT 7
8: 0000000000000468 0 SECTION LOCAL DEFAULT 8
9: 0000000000000488 0 SECTION LOCAL DEFAULT 9
10: 0000000000000548 0 SECTION LOCAL DEFAULT 10
11: 0000000000001000 0 SECTION LOCAL DEFAULT 11
12: 0000000000001020 0 SECTION LOCAL DEFAULT 12
13: 0000000000001040 0 SECTION LOCAL DEFAULT 13
14: 0000000000001050 0 SECTION LOCAL DEFAULT 14
15: 00000000000011b4 0 SECTION LOCAL DEFAULT 15
16: 0000000000002000 0 SECTION LOCAL DEFAULT 16
17: 0000000000002014 0 SECTION LOCAL DEFAULT 17
18: 0000000000002050 0 SECTION LOCAL DEFAULT 18
19: 0000000000003de8 0 SECTION LOCAL DEFAULT 19
20: 0000000000003df0 0 SECTION LOCAL DEFAULT 20
21: 0000000000003df8 0 SECTION LOCAL DEFAULT 21
22: 0000000000003fd8 0 SECTION LOCAL DEFAULT 22
23: 0000000000004000 0 SECTION LOCAL DEFAULT 23
24: 0000000000004020 0 SECTION LOCAL DEFAULT 24
25: 0000000000004030 0 SECTION LOCAL DEFAULT 25
26: 0000000000000000 0 SECTION LOCAL DEFAULT 26
27: 0000000000000000 0 FILE LOCAL DEFAULT ABS crtstuff.c
28: 0000000000001080 0 FUNC LOCAL DEFAULT 14 deregister_tm_clones
29: 00000000000010b0 0 FUNC LOCAL DEFAULT 14 register_tm_clones
30: 00000000000010f0 0 FUNC LOCAL DEFAULT 14 __do_global_dtors_aux
31: 0000000000004030 1 OBJECT LOCAL DEFAULT 25 completed.0
32: 0000000000003df0 0 OBJECT LOCAL DEFAULT 20 __do_global_dtor[...]
33: 0000000000001130 0 FUNC LOCAL DEFAULT 14 frame_dummy
34: 0000000000003de8 0 OBJECT LOCAL DEFAULT 19 __frame_dummy_in[...]
35: 0000000000000000 0 FILE LOCAL DEFAULT ABS a.c
36: 0000000000000000 0 FILE LOCAL DEFAULT ABS crtstuff.c
37: 0000000000002154 0 OBJECT LOCAL DEFAULT 18 __FRAME_END__
38: 0000000000000000 0 FILE LOCAL DEFAULT ABS
39: 0000000000003df0 0 NOTYPE LOCAL DEFAULT 19 __init_array_end
40: 0000000000003df8 0 OBJECT LOCAL DEFAULT 21 _DYNAMIC
41: 0000000000003de8 0 NOTYPE LOCAL DEFAULT 19 __init_array_start
42: 0000000000002014 0 NOTYPE LOCAL DEFAULT 17 __GNU_EH_FRAME_HDR
43: 0000000000004000 0 OBJECT LOCAL DEFAULT 23 _GLOBAL_OFFSET_TABLE_
44: 0000000000001000 0 FUNC LOCAL DEFAULT 11 _init
45: 00000000000011b0 1 FUNC GLOBAL DEFAULT 14 __libc_csu_fini
46: 0000000000000000 0 NOTYPE WEAK DEFAULT UND _ITM_deregisterT[...]
47: 0000000000004020 0 NOTYPE WEAK DEFAULT 24 data_start
48: 0000000000000000 0 FUNC GLOBAL DEFAULT UND puts@GLIBC_2.2.5
49: 0000000000004030 0 NOTYPE GLOBAL DEFAULT 24 _edata
50: 00000000000011b4 0 FUNC GLOBAL HIDDEN 15 _fini
51: 0000000000000000 0 FUNC GLOBAL DEFAULT UND __libc_start_mai[...]
52: 0000000000004020 0 NOTYPE GLOBAL DEFAULT 24 __data_start
53: 0000000000000000 0 NOTYPE WEAK DEFAULT UND __gmon_start__
54: 0000000000004028 0 OBJECT GLOBAL HIDDEN 24 __dso_handle
55: 0000000000002000 4 OBJECT GLOBAL DEFAULT 16 _IO_stdin_used
56: 0000000000001150 93 FUNC GLOBAL DEFAULT 14 __libc_csu_init
57: 0000000000004038 0 NOTYPE GLOBAL DEFAULT 25 _end
58: 0000000000001050 43 FUNC GLOBAL DEFAULT 14 _start
59: 0000000000004030 0 NOTYPE GLOBAL DEFAULT 25 __bss_start
60: 0000000000001135 23 FUNC GLOBAL DEFAULT 14 main
61: 0000000000004030 0 OBJECT GLOBAL HIDDEN 24 __TMC_END__
62: 0000000000000000 0 NOTYPE WEAK DEFAULT UND _ITM_registerTMC[...]
63: 0000000000000000 0 FUNC WEAK DEFAULT UND __cxa_finalize@G[...]
--
Regards,
Peng
