debug_info/调试符号：为什么 nm 不为我的可执行文件显示它们？

Question

为什么 nm 不像目标文件那样显示调试符号？

我的目标文件中所有符号地址都是0，这也正常吗？

MRE：

```
main.c
```
：

#include "foo.h"

int     main()
{
    foo();
    return 0;
}

```
foo.c
```
：

void    foo()
{
}

```
foo.h
```
：

#ifndef FOO_H
# define FOO_H
void    foo();
#endif

```
libfoo.a
```
的制作和符号：

$ gcc -c -g -o foo.o foo.c
$ nm -a foo.o 
0000000000000000 N .debug_abbrev
0000000000000000 N .debug_info
0000000000000000 N .debug_line
0000000000000000 N .debug_line_str
0000000000000000 N .debug_str
0000000000000000 T foo
0000000000000000 a foo.c
0000000000000000 t .text
$ ar rc libfoo.a foo.o
$ nm -a libfoo.a

foo.o:
0000000000000000 N .debug_abbrev
0000000000000000 N .debug_info
0000000000000000 N .debug_line
0000000000000000 N .debug_line_str
0000000000000000 N .debug_str
0000000000000000 T foo
0000000000000000 a foo.c
0000000000000000 t .text
$

编译成可执行文件：

$ gcc -g main.c -L . -lfoo
$ nm -a a.out 
0000000000000000 a 
0000000000004010 B __bss_start
                 w __cxa_finalize@GLIBC_2.2.5
0000000000004000 D __data_start
0000000000004000 W data_start
0000000000004008 D __dso_handle
0000000000003e20 d _DYNAMIC
0000000000004010 D _edata
0000000000004018 B _end
0000000000001138 T _fini
000000000000112e T foo
0000000000000000 a foo.c
0000000000003fe8 d _GLOBAL_OFFSET_TABLE_
                 w __gmon_start__
0000000000002004 r __GNU_EH_FRAME_HDR
0000000000001000 T _init
0000000000002000 R _IO_stdin_used
                 w _ITM_deregisterTMCloneTable
                 w _ITM_registerTMCloneTable
                 U __libc_start_main@GLIBC_2.34
0000000000001119 T main
0000000000000000 a main.c
0000000000001020 T _start
0000000000004010 D __TMC_END__
$

```
file
```
输出：

$ file a.out
a.out: ELF 64-bit LSB pie executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=48cebaa6f43e93bb1805faa5b71d41f1d1e71501, for GNU/Linux 4.4.0, with debug_info, not stripped
$

```
readelf -S
```
输出（附录）：

$ readelf -S a.out
There are 34 section headers, starting at offset 0x37c0:

Section Headers:
  [Nr] Name              Type             Address           Offset
       Size              EntSize          Flags  Link  Info  Align
  [ 0]                   NULL             0000000000000000  00000000
       0000000000000000  0000000000000000           0     0     0
  [ 1] .interp           PROGBITS         0000000000000318  00000318
       000000000000001c  0000000000000000   A       0     0     1
  [ 2] .note.gnu.pr[...] NOTE             0000000000000338  00000338
       0000000000000040  0000000000000000   A       0     0     8
  [ 3] .note.gnu.bu[...] NOTE             0000000000000378  00000378
       0000000000000024  0000000000000000   A       0     0     4
  [ 4] .note.ABI-tag     NOTE             000000000000039c  0000039c
       0000000000000020  0000000000000000   A       0     0     4
  [ 5] .gnu.hash         GNU_HASH         00000000000003c0  000003c0
       000000000000001c  0000000000000000   A       6     0     8
  [ 6] .dynsym           DYNSYM           00000000000003e0  000003e0
       0000000000000090  0000000000000018   A       7     1     8
  [ 7] .dynstr           STRTAB           0000000000000470  00000470
       0000000000000088  0000000000000000   A       0     0     1
  [ 8] .gnu.version      VERSYM           00000000000004f8  000004f8
       000000000000000c  0000000000000002   A       6     0     2
  [ 9] .gnu.version_r    VERNEED          0000000000000508  00000508
       0000000000000030  0000000000000000   A       7     1     8
  [10] .rela.dyn         RELA             0000000000000538  00000538
       00000000000000c0  0000000000000018   A       6     0     8
  [11] .init             PROGBITS         0000000000001000  00001000
       000000000000001b  0000000000000000  AX       0     0     4
  [12] .text             PROGBITS         0000000000001020  00001020
       0000000000000115  0000000000000000  AX       0     0     16
  [13] .fini             PROGBITS         0000000000001138  00001138
       000000000000000d  0000000000000000  AX       0     0     4
  [14] .rodata           PROGBITS         0000000000002000  00002000
       0000000000000004  0000000000000004  AM       0     0     4
  [15] .eh_frame_hdr     PROGBITS         0000000000002004  00002004
       0000000000000024  0000000000000000   A       0     0     4
  [16] .eh_frame         PROGBITS         0000000000002028  00002028
       0000000000000074  0000000000000000   A       0     0     8
  [17] .init_array       INIT_ARRAY       0000000000003e10  00002e10
       0000000000000008  0000000000000008  WA       0     0     8
  [18] .fini_array       FINI_ARRAY       0000000000003e18  00002e18
       0000000000000008  0000000000000008  WA       0     0     8
  [19] .dynamic          DYNAMIC          0000000000003e20  00002e20
       00000000000001a0  0000000000000010  WA       7     0     8
  [20] .got              PROGBITS         0000000000003fc0  00002fc0
       0000000000000028  0000000000000008  WA       0     0     8
  [21] .got.plt          PROGBITS         0000000000003fe8  00002fe8
       0000000000000018  0000000000000008  WA       0     0     8
  [22] .data             PROGBITS         0000000000004000  00003000
       0000000000000010  0000000000000000  WA       0     0     8
  [23] .bss              NOBITS           0000000000004010  00003010
       0000000000000008  0000000000000000  WA       0     0     1
  [24] .comment          PROGBITS         0000000000000000  00003010
       0000000000000036  0000000000000001  MS       0     0     1
  [25] .debug_aranges    PROGBITS         0000000000000000  00003046
       0000000000000060  0000000000000000           0     0     1
  [26] .debug_info       PROGBITS         0000000000000000  000030a6
       00000000000000ab  0000000000000000           0     0     1
  [27] .debug_abbrev     PROGBITS         0000000000000000  00003151
       000000000000007b  0000000000000000           0     0     1
  [28] .debug_line       PROGBITS         0000000000000000  000031cc
       00000000000000a1  0000000000000000           0     0     1
  [29] .debug_str        PROGBITS         0000000000000000  0000326d
       000000000000003d  0000000000000001  MS       0     0     1
  [30] .debug_line_str   PROGBITS         0000000000000000  000032aa
       000000000000003e  0000000000000001  MS       0     0     1
  [31] .symtab           SYMTAB           0000000000000000  000032e8
       0000000000000258  0000000000000018          32     7     8
  [32] .strtab           STRTAB           0000000000000000  00003540
       000000000000011f  0000000000000000           0     0     1
  [33] .shstrtab         STRTAB           0000000000000000  0000365f
       000000000000015c  0000000000000000           0     0     1
Key to Flags:
  W (write), A (alloc), X (execute), M (merge), S (strings), I (info),
  L (link order), O (extra OS processing required), G (group), T (TLS),
  C (compressed), x (unknown), o (OS specific), E (exclude),
  D (mbind), l (large), p (processor specific)

Answer 1

nm -a foo.o

输出的那些调试符号是链接节的名称包含调试信息。编译器将 all 节名称放入符号中目标文件的表，因为链接器需要它们来合并输入部分到输出文件中的输出部分。默认情况下

nm

不报告以下符号部分名称：使用

-a

即可。链接器不放置名称将输出部分合并到输出文件的符号表中，因为任何进一步的合并不再需要它们 - 除非链接是部分链接 (

-Wl,-r

) - 在这种情况下，它们被放入符号表中。

图示：

$ cat foobar.c
static const int bint = 47;

void foo() __attribute__((section(".text.foo")));
void foo()
{
}
int bar() __attribute__((section(".text.bar")));
int bar()
{
    return bint;
}


$ cat foobar.h
#ifndef FOOBAR_H
# define FOOBAR_H
void    foo();
int    bar(); 
#endif


$ cat main.c
#include "foobar.h"

int     main()
{
    foo();
    return bar();
}

$ gcc -g -c main.c foobar.c

符号表操作系统

foobar.o

是：

$ readelf --syms foobar.o

Symbol table '.symtab' contains 14 entries:
   Num:    Value          Size Type    Bind   Vis      Ndx Name
     0: 0000000000000000     0 NOTYPE  LOCAL  DEFAULT  UND 
     1: 0000000000000000     0 FILE    LOCAL  DEFAULT  ABS foobar.c
     2: 0000000000000000     0 SECTION LOCAL  DEFAULT    4 .rodata
     3: 0000000000000000     4 OBJECT  LOCAL  DEFAULT    4 bint
     4: 0000000000000000     0 SECTION LOCAL  DEFAULT    5 .text.foo
     5: 0000000000000000     0 SECTION LOCAL  DEFAULT    6 .text.bar
     6: 0000000000000000     0 SECTION LOCAL  DEFAULT    7 .debug_info
     7: 0000000000000000     0 SECTION LOCAL  DEFAULT    9 .debug_abbrev
     8: 0000000000000000     0 SECTION LOCAL  DEFAULT   12 .debug_rnglists
     9: 0000000000000000     0 SECTION LOCAL  DEFAULT   14 .debug_line
    10: 0000000000000000     0 SECTION LOCAL  DEFAULT   16 .debug_str
    11: 0000000000000000     0 SECTION LOCAL  DEFAULT   17 .debug_line_str
    12: 0000000000000000    11 FUNC    GLOBAL DEFAULT    5 foo
    13: 0000000000000000    15 FUNC    GLOBAL DEFAULT    6 bar

代表了所有部分，包括调试部分。

默认情况下

nm

不报告部分名称：

$ nm foobar.o
0000000000000000 T bar
0000000000000000 r bint
0000000000000000 T foo

但是

nm -a

确实：

$ nm -a foobar.o
0000000000000000 T bar
0000000000000000 r bint
0000000000000000 N .debug_abbrev
0000000000000000 N .debug_info
0000000000000000 N .debug_line
0000000000000000 N .debug_line_str
0000000000000000 N .debug_rnglists
0000000000000000 N .debug_str
0000000000000000 T foo
0000000000000000 a foobar.c
0000000000000000 r .rodata
0000000000000000 t .text.bar
0000000000000000 t .text.foo

现在链接程序并生成地图文件：

$ gcc -g -o prog main.o foobar.o -Wl,-Map=mapfile

（缩写）映射文件显示输入到输出部分合并：

Merging program properties
...[cut]...
Memory Configuration
...[cut]...
Name             Origin             Length             Attributes
*default*        0x0000000000000000 0xffffffffffffffff

Linker script and memory map
...[cut]...
.text           0x0000000000001040      0x121
...[cut]...
 .text          0x0000000000001147        0x0 foobar.o
 .text.foo      0x0000000000001147        0xb foobar.o
                0x0000000000001147                foo
 .text.bar      0x0000000000001152        0xf foobar.o
                0x0000000000001152                bar                
...[cut]...                
.rodata         0x0000000000002000        0x8
...[cut]...
 .rodata        0x0000000000002004        0x4 foobar.o
...[cut]...
.debug_info     0x0000000000000000       0xf9
 *(.debug_info .gnu.linkonce.wi.*)
 .debug_info    0x0000000000000000       0x74 main.o
 .debug_info    0x0000000000000074       0x85 foobar.o
.debug_abbrev   0x0000000000000000       0xcc
 *(.debug_abbrev)
 .debug_abbrev  0x0000000000000000       0x65 main.o
 .debug_abbrev  0x0000000000000065       0x67 foobar.o
.debug_line     0x0000000000000000       0xba
 *(.debug_line .debug_line.* .debug_line_end)
 .debug_line    0x0000000000000000       0x57 main.o
 .debug_line    0x0000000000000057       0x63 foobar.o
...[cut]...
.debug_str      0x0000000000000000       0x98
 *(.debug_str)
 .debug_str     0x0000000000000000       0x98 main.o
                                         0x93 (size before relaxing)
 .debug_str     0x0000000000000098       0x93 foobar.o
...[cut]...
.debug_line_str
                0x0000000000000000       0x34
 *(.debug_line_str)
 .debug_line_str
                0x0000000000000000       0x34 main.o
                                         0x54 (size before relaxing)
 .debug_line_str
                0x0000000000000034       0x51 foobar.o     
...[cut] ...
OUTPUT(prog elf64-x86-64)

注意例如输入函数部分

text.foo

和

text.bar

如何合并到输出

.text

部分。

所有节名称都从输出文件的符号表中消失了：

$ readelf -W --syms prog

Symbol table '.dynsym' contains 6 entries:
   Num:    Value          Size Type    Bind   Vis      Ndx Name
     0: 0000000000000000     0 NOTYPE  LOCAL  DEFAULT  UND 
     1: 0000000000000000     0 FUNC    GLOBAL DEFAULT  UND __libc_start_main@GLIBC_2.34 (2)
     2: 0000000000000000     0 NOTYPE  WEAK   DEFAULT  UND _ITM_deregisterTMCloneTable
     3: 0000000000000000     0 NOTYPE  WEAK   DEFAULT  UND __gmon_start__
     4: 0000000000000000     0 NOTYPE  WEAK   DEFAULT  UND _ITM_registerTMCloneTable
     5: 0000000000000000     0 FUNC    WEAK   DEFAULT  UND __cxa_finalize@GLIBC_2.2.5 (3)

Symbol table '.symtab' contains 39 entries:
   Num:    Value          Size Type    Bind   Vis      Ndx Name
     0: 0000000000000000     0 NOTYPE  LOCAL  DEFAULT  UND 
     1: 0000000000000000     0 FILE    LOCAL  DEFAULT  ABS Scrt1.o
     2: 000000000000038c    32 OBJECT  LOCAL  DEFAULT    4 __abi_tag
     3: 0000000000000000     0 FILE    LOCAL  DEFAULT  ABS crtstuff.c
     4: 0000000000001070     0 FUNC    LOCAL  DEFAULT   14 deregister_tm_clones
     5: 00000000000010a0     0 FUNC    LOCAL  DEFAULT   14 register_tm_clones
     6: 00000000000010e0     0 FUNC    LOCAL  DEFAULT   14 __do_global_dtors_aux
     7: 0000000000004010     1 OBJECT  LOCAL  DEFAULT   24 completed.0
     8: 0000000000003df8     0 OBJECT  LOCAL  DEFAULT   20 __do_global_dtors_aux_fini_array_entry
     9: 0000000000001120     0 FUNC    LOCAL  DEFAULT   14 frame_dummy
    10: 0000000000003df0     0 OBJECT  LOCAL  DEFAULT   19 __frame_dummy_init_array_entry
    11: 0000000000000000     0 FILE    LOCAL  DEFAULT  ABS main.c
    12: 0000000000000000     0 FILE    LOCAL  DEFAULT  ABS foobar.c
    13: 0000000000002004     4 OBJECT  LOCAL  DEFAULT   16 bint
    14: 0000000000000000     0 FILE    LOCAL  DEFAULT  ABS crtstuff.c
    15: 0000000000002118     0 OBJECT  LOCAL  DEFAULT   18 __FRAME_END__
    16: 0000000000000000     0 FILE    LOCAL  DEFAULT  ABS 
    17: 0000000000003e00     0 OBJECT  LOCAL  DEFAULT   21 _DYNAMIC
    18: 0000000000002008     0 NOTYPE  LOCAL  DEFAULT   17 __GNU_EH_FRAME_HDR
    19: 0000000000003fc0     0 OBJECT  LOCAL  DEFAULT   22 _GLOBAL_OFFSET_TABLE_
    20: 0000000000000000     0 FUNC    GLOBAL DEFAULT  UND __libc_start_main@GLIBC_2.34
    21: 0000000000000000     0 NOTYPE  WEAK   DEFAULT  UND _ITM_deregisterTMCloneTable
    22: 0000000000004000     0 NOTYPE  WEAK   DEFAULT   23 data_start
    23: 0000000000004010     0 NOTYPE  GLOBAL DEFAULT   23 _edata
    24: 0000000000001152    15 FUNC    GLOBAL DEFAULT   14 bar
    25: 0000000000001164     0 FUNC    GLOBAL HIDDEN    15 _fini
    26: 0000000000004000     0 NOTYPE  GLOBAL DEFAULT   23 __data_start
    27: 0000000000000000     0 NOTYPE  WEAK   DEFAULT  UND __gmon_start__
    28: 0000000000004008     0 OBJECT  GLOBAL HIDDEN    23 __dso_handle
    29: 0000000000002000     4 OBJECT  GLOBAL DEFAULT   16 _IO_stdin_used
    30: 0000000000001147    11 FUNC    GLOBAL DEFAULT   14 foo
    31: 0000000000004018     0 NOTYPE  GLOBAL DEFAULT   24 _end
    32: 0000000000001040    38 FUNC    GLOBAL DEFAULT   14 _start
    33: 0000000000004010     0 NOTYPE  GLOBAL DEFAULT   24 __bss_start
    34: 0000000000001129    30 FUNC    GLOBAL DEFAULT   14 main
    35: 0000000000004010     0 OBJECT  GLOBAL HIDDEN    23 __TMC_END__
    36: 0000000000000000     0 NOTYPE  WEAK   DEFAULT  UND _ITM_registerTMCloneTable
    37: 0000000000000000     0 FUNC    WEAK   DEFAULT  UND __cxa_finalize@GLIBC_2.2.5
    38: 0000000000001000     0 FUNC    GLOBAL HIDDEN    11 _init

但是输出节名称仍然是节名称：

$ readelf -S prog
There are 36 section headers, starting at offset 0x3b10:

Section Headers:
  [Nr] Name              Type             Address           Offset
       Size              EntSize          Flags  Link  Info  Align
  [ 0]                   NULL             0000000000000000  00000000
       0000000000000000  0000000000000000           0     0     0
  [ 1] .interp           PROGBITS         0000000000000318  00000318
       000000000000001c  0000000000000000   A       0     0     1
  [ 2] .note.gnu.pr[...] NOTE             0000000000000338  00000338
       0000000000000030  0000000000000000   A       0     0     8
  [ 3] .note.gnu.bu[...] NOTE             0000000000000368  00000368
       0000000000000024  0000000000000000   A       0     0     4
  [ 4] .note.ABI-tag     NOTE             000000000000038c  0000038c
       0000000000000020  0000000000000000   A       0     0     4
  [ 5] .gnu.hash         GNU_HASH         00000000000003b0  000003b0
       0000000000000024  0000000000000000   A       6     0     8
  [ 6] .dynsym           DYNSYM           00000000000003d8  000003d8
       0000000000000090  0000000000000018   A       7     1     8
  [ 7] .dynstr           STRTAB           0000000000000468  00000468
       0000000000000088  0000000000000000   A       0     0     1
  [ 8] .gnu.version      VERSYM           00000000000004f0  000004f0
       000000000000000c  0000000000000002   A       6     0     2
  [ 9] .gnu.version_r    VERNEED          0000000000000500  00000500
       0000000000000030  0000000000000000   A       7     1     8
  [10] .rela.dyn         RELA             0000000000000530  00000530
       00000000000000c0  0000000000000018   A       6     0     8
  [11] .init             PROGBITS         0000000000001000  00001000
       000000000000001b  0000000000000000  AX       0     0     4
  [12] .plt              PROGBITS         0000000000001020  00001020
       0000000000000010  0000000000000010  AX       0     0     16
  [13] .plt.got          PROGBITS         0000000000001030  00001030
       0000000000000010  0000000000000010  AX       0     0     16
  [14] .text             PROGBITS         0000000000001040  00001040
       0000000000000121  0000000000000000  AX       0     0     16
  [15] .fini             PROGBITS         0000000000001164  00001164
       000000000000000d  0000000000000000  AX       0     0     4
  [16] .rodata           PROGBITS         0000000000002000  00002000
       0000000000000008  0000000000000000   A       0     0     4
  [17] .eh_frame_hdr     PROGBITS         0000000000002008  00002008
       000000000000003c  0000000000000000   A       0     0     4
  [18] .eh_frame         PROGBITS         0000000000002048  00002048
       00000000000000d4  0000000000000000   A       0     0     8
  [19] .init_array       INIT_ARRAY       0000000000003df0  00002df0
       0000000000000008  0000000000000008  WA       0     0     8
  [20] .fini_array       FINI_ARRAY       0000000000003df8  00002df8
       0000000000000008  0000000000000008  WA       0     0     8
  [21] .dynamic          DYNAMIC          0000000000003e00  00002e00
       00000000000001c0  0000000000000010  WA       7     0     8
  [22] .got              PROGBITS         0000000000003fc0  00002fc0
       0000000000000040  0000000000000008  WA       0     0     8
  [23] .data             PROGBITS         0000000000004000  00003000
       0000000000000010  0000000000000000  WA       0     0     8
  [24] .bss              NOBITS           0000000000004010  00003010
       0000000000000008  0000000000000000  WA       0     0     1
  [25] .comment          PROGBITS         0000000000000000  00003010
       0000000000000026  0000000000000001  MS       0     0     1
  [26] .debug_aranges    PROGBITS         0000000000000000  00003036
       0000000000000070  0000000000000000           0     0     1
  [27] .debug_info       PROGBITS         0000000000000000  000030a6
       00000000000000f9  0000000000000000           0     0     1
  [28] .debug_abbrev     PROGBITS         0000000000000000  0000319f
       00000000000000cc  0000000000000000           0     0     1
  [29] .debug_line       PROGBITS         0000000000000000  0000326b
       00000000000000ba  0000000000000000           0     0     1
  [30] .debug_str        PROGBITS         0000000000000000  00003325
       0000000000000098  0000000000000001  MS       0     0     1
  [31] .debug_line_str   PROGBITS         0000000000000000  000033bd
       0000000000000034  0000000000000001  MS       0     0     1
  [32] .debug_rnglists   PROGBITS         0000000000000000  000033f1
       0000000000000021  0000000000000000           0     0     1
  [33] .symtab           SYMTAB           0000000000000000  00003418
       00000000000003a8  0000000000000018          34    20     8
  [34] .strtab           STRTAB           0000000000000000  000037c0
       00000000000001df  0000000000000000           0     0     1
  [35] .shstrtab         STRTAB           0000000000000000  0000399f
       000000000000016c  0000000000000000           0     0     1

.text

部分当然会保留下来，但

.text.foo

和

.text.bar

不会，已合并为

.text

.

另一方面，如果我们执行部分链接：

$ gcc -r -g -o prog main.o foobar.o

然后节名称进入符号表：

$ readelf --syms prog

Symbol table '.symtab' contains 24 entries:
   Num:    Value          Size Type    Bind   Vis      Ndx Name
     0: 0000000000000000     0 NOTYPE  LOCAL  DEFAULT  UND 
     1: 0000000000000000     0 SECTION LOCAL  DEFAULT    1 .note.gnu.property
     2: 0000000000000000     0 SECTION LOCAL  DEFAULT    2 .text
     3: 0000000000000000     0 SECTION LOCAL  DEFAULT    4 .text.foo
     4: 0000000000000000     0 SECTION LOCAL  DEFAULT    5 .text.bar
     5: 0000000000000000     0 SECTION LOCAL  DEFAULT    6 .rodata
     6: 0000000000000000     0 SECTION LOCAL  DEFAULT    7 .eh_frame
     7: 0000000000000000     0 SECTION LOCAL  DEFAULT    9 .data
     8: 0000000000000000     0 SECTION LOCAL  DEFAULT   10 .bss
     9: 0000000000000000     0 SECTION LOCAL  DEFAULT   11 .comment
    10: 0000000000000000     0 SECTION LOCAL  DEFAULT   12 .note.GNU-stack
    11: 0000000000000000     0 SECTION LOCAL  DEFAULT   13 .debug_aranges
    12: 0000000000000000     0 SECTION LOCAL  DEFAULT   15 .debug_info
    13: 0000000000000000     0 SECTION LOCAL  DEFAULT   17 .debug_abbrev
    14: 0000000000000000     0 SECTION LOCAL  DEFAULT   18 .debug_line
    15: 0000000000000000     0 SECTION LOCAL  DEFAULT   20 .debug_str
    16: 0000000000000000     0 SECTION LOCAL  DEFAULT   21 .debug_line_str
    17: 0000000000000000     0 SECTION LOCAL  DEFAULT   22 .debug_rnglists
    18: 0000000000000000     0 FILE    LOCAL  DEFAULT  ABS main.c
    19: 0000000000000000     0 FILE    LOCAL  DEFAULT  ABS foobar.c
    20: 0000000000000000     4 OBJECT  LOCAL  DEFAULT    6 bint
    21: 0000000000000000    30 FUNC    GLOBAL DEFAULT    2 main
    22: 0000000000000000    11 FUNC    GLOBAL DEFAULT    4 foo
    23: 0000000000000000    15 FUNC    GLOBAL DEFAULT    5 bar

他们的报道者：

$ nm -a prog
0000000000000000 T bar
0000000000000000 r bint
0000000000000000 b .bss
0000000000000000 n .comment
0000000000000000 d .data
0000000000000000 N .debug_abbrev
0000000000000000 N .debug_aranges
0000000000000000 N .debug_info
0000000000000000 N .debug_line
0000000000000000 N .debug_line_str
0000000000000000 N .debug_rnglists
0000000000000000 N .debug_str
0000000000000000 r .eh_frame
0000000000000000 T foo
0000000000000000 a foobar.c
0000000000000000 T main
0000000000000000 a main.c
0000000000000000 r .note.gnu.property
0000000000000000 n .note.GNU-stack
0000000000000000 r .rodata
0000000000000000 t .text
0000000000000000 t .text.bar
0000000000000000 t .text.foo

debug_info/调试符号：为什么 nm 不为我的可执行文件显示它们？

问题描述投票：0回答：1

MRE：

1个回答

最新问题

debug_info/调试符号：为什么 nm 不为我的可执行文件显示它们？

问题描述 投票：0回答：1

MRE：

1个回答

最新问题

问题描述投票：0回答：1