GCC 编译器的链接脚本

 

查看方式

使用 gcc 命令可以查看其使用的默认脚本

gcc -Wl,-verbose

脚本内容

using internal linker script:
==================================================
/* Script for -z combreloc: combine and sort reloc sections */
/* Copyright (C) 2014-2015 Free Software Foundation, Inc.
   Copying and distribution of this script, with or without modification,
   are permitted in any medium without royalty provided the copyright
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}


==================================================

可以看出代码段总是从 0x400000 开始。

对一个 c 文件 c.c

cat c.c 
int main()
{}

可以查看代码段中 main 所在的地址就是 00000000004004d6 T main

nm c
0000000000601030 B __bss_start
0000000000601030 b completed.7594
0000000000601020 D __data_start
0000000000601020 W data_start
0000000000400410 t deregister_tm_clones
0000000000400490 t __do_global_dtors_aux
0000000000600e18 t __do_global_dtors_aux_fini_array_entry
0000000000601028 D __dso_handle
0000000000600e28 d _DYNAMIC
0000000000601030 D _edata
0000000000601038 B _end
0000000000400564 T _fini
00000000004004b0 t frame_dummy
0000000000600e10 t __frame_dummy_init_array_entry
0000000000400698 r __FRAME_END__
0000000000601000 d _GLOBAL_OFFSET_TABLE_
                 w __gmon_start__
0000000000400574 r __GNU_EH_FRAME_HDR
0000000000400390 T _init
0000000000600e18 t __init_array_end
0000000000600e10 t __init_array_start
0000000000400570 R _IO_stdin_used
                 w _ITM_deregisterTMCloneTable
                 w _ITM_registerTMCloneTable
0000000000600e20 d __JCR_END__
0000000000600e20 d __JCR_LIST__
                 w _Jv_RegisterClasses
0000000000400560 T __libc_csu_fini
00000000004004f0 T __libc_csu_init
                 U __libc_start_main@@GLIBC_2.2.5
00000000004004d6 T main
0000000000400450 t register_tm_clones
00000000004003e0 T _start
0000000000601030 D __TMC_END__