我认为这个问题与整数格式无关,而与文件名有关。
FIRST_PROG.c
和可执行文件名
COMPILED_1
第二次使用文件名
SECOND_PROC.c
和可执行文件名
COMPILED_2
gcc
没有设置其他标志:
int main() {
return 0;
}
如果你
hd
生成的可执行文件的内容,在某个偏移量处,您可以看到:
00001720 66 72 61 6d 65 5f 64 75 6d 6d 79 5f 69 6e 69 74 |frame_dummy_init|
00001730 5f 61 72 72 61 79 5f 65 6e 74 72 79 00 46 49 52 |_array_entry.FIR|
00001740 53 54 5f 50 52 4f 47 2e 63 00 5f 5f 46 52 41 4d |ST_PROG.c.__FRAM|
注意,源文件的名称,
第一个程序。c
00001720 66 72 61 6d 65 5f 64 75 6d 6d 79 5f 69 6e 69 74 |frame_dummy_init|
00001730 5f 61 72 72 61 79 5f 65 6e 74 72 79 00 53 45 43 |_array_entry.SEC|
00001740 4f 4e 44 5f 50 52 4f 47 2e 63 00 5f 5f 46 52 41 |OND_PROG.c.__FRA|
你可以看到
SECOND_PROG.c
也嵌入到二进制文件中。
转储两个可执行文件
objdump -s
在任何地方都没有显示,这与干净的
diff
你从你的程序中得到了。但是,使用
readelf -a
列出生成的可执行文件的内容
做
显示以下内容:
Symbol table '.symtab' contains 66 entries:
Num: Value Size Type Bind Vis Ndx Name
0: 0000000000000000 0 NOTYPE LOCAL DEFAULT UND
1: 0000000000400238 0 SECTION LOCAL DEFAULT 1
2: 0000000000400254 0 SECTION LOCAL DEFAULT 2
3: 0000000000400274 0 SECTION LOCAL DEFAULT 3
4: 0000000000400298 0 SECTION LOCAL DEFAULT 4
5: 00000000004002b8 0 SECTION LOCAL DEFAULT 5
6: 0000000000400300 0 SECTION LOCAL DEFAULT 6
7: 0000000000400338 0 SECTION LOCAL DEFAULT 7
8: 0000000000400340 0 SECTION LOCAL DEFAULT 8
9: 0000000000400360 0 SECTION LOCAL DEFAULT 9
10: 0000000000400378 0 SECTION LOCAL DEFAULT 10
11: 0000000000400390 0 SECTION LOCAL DEFAULT 11
12: 00000000004003b0 0 SECTION LOCAL DEFAULT 12
13: 00000000004003d0 0 SECTION LOCAL DEFAULT 13
14: 00000000004003e0 0 SECTION LOCAL DEFAULT 14
15: 0000000000400564 0 SECTION LOCAL DEFAULT 15
16: 0000000000400570 0 SECTION LOCAL DEFAULT 16
17: 0000000000400574 0 SECTION LOCAL DEFAULT 17
18: 00000000004005a8 0 SECTION LOCAL DEFAULT 18
19: 0000000000600e10 0 SECTION LOCAL DEFAULT 19
20: 0000000000600e18 0 SECTION LOCAL DEFAULT 20
21: 0000000000600e20 0 SECTION LOCAL DEFAULT 21
22: 0000000000600e28 0 SECTION LOCAL DEFAULT 22
23: 0000000000600ff8 0 SECTION LOCAL DEFAULT 23
24: 0000000000601000 0 SECTION LOCAL DEFAULT 24
25: 0000000000601020 0 SECTION LOCAL DEFAULT 25
26: 0000000000601030 0 SECTION LOCAL DEFAULT 26
27: 0000000000000000 0 SECTION LOCAL DEFAULT 27
28: 0000000000000000 0 FILE LOCAL DEFAULT ABS crtstuff.c
29: 0000000000600e20 0 OBJECT LOCAL DEFAULT 21 __JCR_LIST__
30: 0000000000400410 0 FUNC LOCAL DEFAULT 14 deregister_tm_clones
31: 0000000000400450 0 FUNC LOCAL DEFAULT 14 register_tm_clones
32: 0000000000400490 0 FUNC LOCAL DEFAULT 14 __do_global_dtors_aux
33: 0000000000601030 1 OBJECT LOCAL DEFAULT 26 completed.7585
34: 0000000000600e18 0 OBJECT LOCAL DEFAULT 20 __do_global_dtors_aux_fin
35: 00000000004004b0 0 FUNC LOCAL DEFAULT 14 frame_dummy
36: 0000000000600e10 0 OBJECT LOCAL DEFAULT 19 __frame_dummy_init_array_
37: 0000000000000000 0 FILE LOCAL DEFAULT ABS FIRST_PROG.c
38: 0000000000000000 0 FILE LOCAL DEFAULT ABS crtstuff.c
39: 0000000000400698 0 OBJECT LOCAL DEFAULT 18 __FRAME_END__
40: 0000000000600e20 0 OBJECT LOCAL DEFAULT 21 __JCR_END__
41: 0000000000000000 0 FILE LOCAL DEFAULT ABS
42: 0000000000600e18 0 NOTYPE LOCAL DEFAULT 19 __init_array_end
43: 0000000000600e28 0 OBJECT LOCAL DEFAULT 22 _DYNAMIC
44: 0000000000600e10 0 NOTYPE LOCAL DEFAULT 19 __init_array_start
45: 0000000000400574 0 NOTYPE LOCAL DEFAULT 17 __GNU_EH_FRAME_HDR
46: 0000000000601000 0 OBJECT LOCAL DEFAULT 24 _GLOBAL_OFFSET_TABLE_
47: 0000000000400560 2 FUNC GLOBAL DEFAULT 14 __libc_csu_fini
48: 0000000000000000 0 NOTYPE WEAK DEFAULT UND _ITM_deregisterTMCloneTab
49: 0000000000601020 0 NOTYPE WEAK DEFAULT 25 data_start
50: 0000000000601030 0 NOTYPE GLOBAL DEFAULT 25 _edata
51: 0000000000400564 0 FUNC GLOBAL DEFAULT 15 _fini
52: 0000000000000000 0 FUNC GLOBAL DEFAULT UND __libc_start_main@@GLIBC_
53: 0000000000601020 0 NOTYPE GLOBAL DEFAULT 25 __data_start
54: 0000000000000000 0 NOTYPE WEAK DEFAULT UND __gmon_start__
55: 0000000000601028 0 OBJECT GLOBAL HIDDEN 25 __dso_handle
56: 0000000000400570 4 OBJECT GLOBAL DEFAULT 16 _IO_stdin_used
57: 00000000004004f0 101 FUNC GLOBAL DEFAULT 14 __libc_csu_init
58: 0000000000601038 0 NOTYPE GLOBAL DEFAULT 26 _end
59: 00000000004003e0 42 FUNC GLOBAL DEFAULT 14 _start
60: 0000000000601030 0 NOTYPE GLOBAL DEFAULT 26 __bss_start
61: 00000000004004d6 11 FUNC GLOBAL DEFAULT 14 main
62: 0000000000000000 0 NOTYPE WEAK DEFAULT UND _Jv_RegisterClasses
63: 0000000000601030 0 OBJECT GLOBAL HIDDEN 25 __TMC_END__
64: 0000000000000000 0 NOTYPE WEAK DEFAULT UND _ITM_registerTMCloneTable
65: 0000000000400390 0 FUNC GLOBAL DEFAULT 11 _init
注意,条目37包含源文件的名称。如果你尝试
差异
ing的输出
readelf-a
81c81
< [28] .shstrtab STRTAB 0000000000000000 0000189f
---
> [28] .shstrtab STRTAB 0000000000000000 000018a0
86c86
< 0000000000000207 0000000000000000 0 0 1
---
> 0000000000000208 0000000000000000 0 0 1
211c211
< 37: 0000000000000000 0 FILE LOCAL DEFAULT ABS FIRST_PROG.c
---
> 37: 0000000000000000 0 FILE LOCAL DEFAULT ABS SECOND_PROG.c
258c258
< Build ID: 2c64961288049002e34a1f14e55d6c80dd96816c
---
> Build ID: 5425dec81aae53bd30e85fe94659d320bb774dcc
似乎这些差异中的许多归结为源文件的名称不同。
所以我的官方答案是“这与整数文字无关,只是编译具有不同名称的文件的函数。”
