ld_verbose.txt

GNU ld (GNU Binutils for Ubuntu) 2.30
  Supported emulations:
   elf_x86_64
   elf32_x86_64
   elf_i386
   elf_iamcu
   i386linux
   elf_l1om
   elf_k1om
   i386pep
   i386pe
using internal linker script:
==================================================
/* Script for -z combreloc: combine and sort reloc sections */
/* Copyright (C) 2014-2018 Free Software Foundation, Inc.
   Copying and distribution of this script, with or without modification,
   are permitted in any medium without royalty provided the copyright
   notice and this notice are preserved.  */
OUTPUT_FORMAT("elf64-x86-64", "elf64-x86-64",
	      "elf64-x86-64")
OUTPUT_ARCH(i386:x86-64)
ENTRY(_start)
SEARCH_DIR("=/usr/local/lib/x86_64-linux-gnu"); SEARCH_DIR("=/lib/x86_64-linux-gnu"); SEARCH_DIR("=/usr/lib/x86_64-linux-gnu"); SEARCH_DIR("=/usr/lib/x86_64-linux-gnu64"); SEARCH_DIR("=/usr/local/lib64"); SEARCH_DIR("=/lib64"); SEARCH_DIR("=/usr/lib64"); SEARCH_DIR("=/usr/local/lib"); SEARCH_DIR("=/lib"); SEARCH_DIR("=/usr/lib"); SEARCH_DIR("=/usr/x86_64-linux-gnu/lib64"); SEARCH_DIR("=/usr/x86_64-linux-gnu/lib");
SECTIONS
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  .ctors          :
  {
    /* gcc uses crtbegin.o to find the start of
       the constructors, so we make sure it is
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    KEEP (*crtbegin.o(.ctors))
    KEEP (*crtbegin?.o(.ctors))
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    KEEP (*(.ctors))
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  {
    KEEP (*crtbegin.o(.dtors))
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}

Hello, I see your document, there is a question I want to ask you. Is there an official document describing the linker script in gnu? How to read and understand it？

@1367485513

You can see this file in ld --verbose option.
Or if you want to read linker scripts more easily, I recommend to set -M option in ld command, which means "Map".
Here is an example:

$ ld -T hello.ld hello0.o -M

Memory Configuration

Name             Origin             Length             Attributes
*default*        0x0000000000000000 0xffffffffffffffff

Linker script and memory map

                0x0000000008048054                . = (0x8048000 + SIZEOF_HEADERS)

.text           0x0000000008048054       0x2b
 *(.text)
 .text          0x0000000008048054       0x2b hello0.o
                0x0000000008048054                main
                0x000000000804807f                PROVIDE (etext, .)

.rodata
 *(.rodata)
                0x000000000804807f                PROVIDE (data, .)

.data           0x000000000804807f        0x0
 *(.data)
 .data          0x000000000804807f        0x0 hello0.o
                0x000000000804807f                PROVIDE (edata, .)

.bss            0x000000000804807f        0x0
 *(.bss)
 .bss           0x000000000804807f        0x0 hello0.o
                0x000000000804807f                PROVIDE (end, .)

/DISCARD/
 *(.eh_frame_hdr .note.gnu.build-id)
LOAD hello0.o
OUTPUT(a.out elf32-i386)

and

// hello.ld
SECTIONS
{
  /* location counter */
  . = 0x08048000 + SIZEOF_HEADERS;
  .text : { *(.text) }
  PROVIDE(etext = .);   /* Define the 'etext' symbol to this value */
  .rodata : { *(.rodata) }

    PROVIDE(data = .);
  .data : { *(.data) }
    /* Adjust the address for the data segment to the next page */
    /*. = ALIGN(0x1000); */
    PROVIDE(edata = .);
  .bss : { *(.bss) }
    PROVIDE(end = .);

    /DISCARD/ : {
        *(.eh_frame_hdr .note.gnu.build-id)
    }
}

yes.i know that.I want to find an official document introducing him.such as ：https://sourceware.org/binutils/docs/ld/Scripts.html#Scripts

…

------------------ 原始邮件 ------------------ 发件人: "Kenta Nakajima"<notifications@github.com>; 发送时间: 2019年7月31日(星期三) 下午2:59 收件人: "knknkn1162"<knknkn1162@noreply.github.com>; 抄送: "jhma"<1367485513@qq.com>; "Mention"<mention@noreply.github.com>; 主题: Re: knknkn1162/ld_verbose.txt @1367485513 You can see this file in ld --verbose option. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub, or mute the thread.

I don't know the kind of tutorial in linker script, but I can just read this because I have the knowledge of ELF(Executable and Linkable File).
It's not difficult to understand linker scripts if you can do ELF format.

ok,thanks a lot

…

---Original--- From: "Kenta Nakajima"<notifications@github.com> Date: Wed, Jul 31, 2019 15:37 PM To: "knknkn1162"<knknkn1162@noreply.github.com>; Cc: "1367485513"<1367485513@qq.com>;"Mention"<mention@noreply.github.com>; Subject: Re: knknkn1162/ld_verbose.txt I don't know the kind of tutorial in linker script, but I can just read this because I have the knowledge of ELF(Executable and Linkable File). It's not difficult to understand linker scripts if you can do ELF format. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub, or mute the thread.