我想從我正在閱讀的程序集書中找到一個簡單的示例。我正試圖讓gdb與我正在與NASM彙編程序彙編的簡單彙編程序一起工作。以下是代碼，以及elf格式的對象文件。NASM和GDB符號：「在符號文件中找不到任何代碼段」。
; Version : 1.0
; Created Date : 11/12/2011
; Last Update : 11/12/2011
; Author : Jeff Duntemann
; Description : A simple assembly app for Linux, using NASM 2.05,
; demonstrating the use of Linux INT 80H syscalls
; to display text.
; Build using these commands:
; nasm -f elf -g -F stabs eatsyscall.asm
; ld -o eatsyscall eatsyscall.o
;
SECTION .data ; Section containing initialized data
EatMsg: db "Eat at Joe's!",10
EatLen: equ $-EatMsg
SECTION .bss ; Section containing uninitialized data
SECTION .txt ; Section containing code
global _start ; Linker needs this to find the entry point!
_start:
nop ; This no_op keeps gdb happy (see text)
mov eax,4 ; Specify sys_write syscall
mov ebx,1 ; Specify File Descriptor 1: Standard Output
mov ecx,EatMsg ; Pass offset of the message
mov edx,EatLen ; Pass the length of the mesage
int 80H ; Make syscall to output the text to stdout
mov eax,1 ; Specify Exit syscall
mov ebx,0 ; Return a code of zero
int 80H ; Make syscall to terminate the program
和
[email protected]:~/Code/AsmWork/eatsyscall$ objdump -s ./eatsyscall.o
./eatsyscall.o: file format elf32-i386
Contents of section .data:
0000 45617420 6174204a 6f652773 210a Eat at Joe's!.
Contents of section .txt:
0000 90b80400 0000bb01 000000b9 00000000 ................
0010 ba0e0000 00cd80b8 01000000 bb000000 ................
0020 00cd80 ...
Contents of section .stab:
0000 00000000 64000100 00000000 ....d.......
Contents of section .stabstr:
0000 00
我使用下面的命令來組裝：
nasm -f elf -g -F stabs eatsyscall.asm
，我使用下面的命令鏈接：
ld -o eatsyscall eatsyscall.o
當我在我得到的可執行文件上運行GDB以下：
[email protected]:~/Code/AsmWork/eatsyscall$ gdb eatsyscall
GNU gdb (Ubuntu/Linaro 7.3-0ubuntu2) 7.3-2011.08
Copyright (C) 2011 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law. Type "show copying"
and "show warranty" for details.
This GDB was configured as "i686-linux-gnu".
For bug reporting instructions, please see:
<http://bugs.launchpad.net/gdb-linaro/>...
Reading symbols from /home/mehoggan/Code/AsmWork/eatsyscall/eatsyscall...Can't find any code sections in symbol file
(gdb) quit
我需要什麼，除了我所完成以上工作得到GDB讀取指定NASM用-g標誌將調試符號呢？
FYI
[email protected]:~/Code/AsmWork/eatsyscall$ cat /etc/*release*
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=11.10
DISTRIB_CODENAME=oneiric
DISTRIB_DESCRIPTION="Ubuntu 11.10"
[email protected]:~/Code/AsmWork/eatsyscall$ uname -a
Linux mehoggan 3.0.0-12-generic-pae #20-Ubuntu SMP Fri Oct 7 16:37:17 UTC 2011 i686 i686 i386 GNU/Linux
[email protected]:~/Code/AsmWork/eatsyscall$
--Update--
即使我走了64位路由使用下面的命令，我仍然沒有成功：
mehoggan @ mehoggan ：〜/ Code/AsmWork/eatsyscall $ nasm -f elf64 -g -F stabs eatsyscall.asm mehoggan @ mehoggan：〜/ Code/AsmWork/eatsyscall $ ld -o eatsyscall eatsyscall.o -melf_x86_64 mehoggan @ mehoggan：〜/代碼/ AsmWork/eatsyscall $ ./eatsyscall 慶典：./eatsyscall：不能執行二進制文件 mehoggan @ mehoggan：〜/代碼/ AsmWork/eatsyscall $ objdump的-s eatsyscall.o
eatsyscall.o：文件格式elf64-x86-64
部分內容.data： 0000 45617420 6174204a 6f652773 210a在Joe's吃過！
section .txt的內容： 0000 9048b804 00000000 00000048 bb010000 .H ......... H .... 0010 00000000 0048b900 00000000 00000048 ..... H ........ H 0020 ba0e0000 00000000 00cd8048 b8010000 ............ H .... 0030 00000000 0048bb00 00000000 000000cd ..... H .......... 0040 80。
section .stab的內容： 0000 00000000 64000100 00000000 .... d .......
section .stabstr的內容： 0000 00。
mehoggan @ mehoggan：〜/代碼/ AsmWork/eatsyscall $
只是爲了跟進此： 我用祝福來編輯非兼容的.o文件，並手動歸零64對應的.stab部分中的最後'd'。 用這個手動修改過的文件重建exe後，一切正常。 這是64說它試圖創建一個64位的對象文件？ （我的Oneiric版本是32位。） – Kaitain