我试图找出一个非常奇怪的问题.我有带有gdb的CentOS 6.5系统:
GNU gdb (GDB) Red Hat Enterprise Linux (7.2-75.el6)
和gcc:
gcc (GCC) 4.8.2 20131212 (Red Hat 4.8.2-8)
我有这个文件:
#include<stdio.h>
int main()
{
printf("OK!");
return 0;
}
我用它编译:
gcc -o a a.c -g -O0
该文件似乎很好:
$file a
a: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.18, not stripped
但是当我尝试调试它时,会发生这种情况:
$gdb a
GNU gdb (GDB) Red Hat Enterprise Linux (7.2-75.el6)
Copyright (C) 2010 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 "x86_64-redhat-linux-gnu".
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>...
Reading symbols from a...done.
(gdb) b main
Breakpoint 1 at 0x4004e4
(gdb) r
Starting program: a
Breakpoint 1, 0x00000000004004e4 in main ()
(gdb) l
1 /* Run time dynamic linker.
2 Copyright (C) 1995-2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
(gdb) l main
No line number known for main.
即,gdb拒绝查看任何调试信息.有人知道这里可能有什么问题吗?
解决方法:
您的GDB很老了.您的GCC非常新.
我怀疑您的GCC正在发出DWARF4调试信息(根据release notes,默认值为gcc-4.8),您的GDB无法识别该信息.
使用-gdwarf-2而不是-g可以获得更好的结果吗?
如果是这样,请升级您的GDB或将此编译器与-gdwarf-2一起使用.