快速定位段错误

最新推荐文章于 2023-08-01 09:59:12 发布

转载最新推荐文章于 2023-08-01 09:59:12 发布 · 231 阅读

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原文链接：http://www.cnblogs.com/abcdk/p/5682709.html

本文通过一个简单的C++程序示例，介绍了如何复现并利用GDB调试程序中的段错误问题，详细展示了从创建错误程序、编译、设置ulimit参数到生成及分析core文件的全过程。

1.先写一个会产生段错误的程序：

test.cpp

#include <stdio.h>
#include <string.h>

void fun()
{
    char *ptr;
    memcpy(ptr, "abc", 3);
}

int main()
{
    fun();

    return 0;
}

2.编译程序 g++ -g test.cpp -o test

3.使用ulimit -c unlimited命令，使程序产生段错误时可以产生core文件

4.gdb test core.*** 调试程序

[root@localhost mnt]# gdb test core.2660 
GNU gdb (GDB) Red Hat Enterprise Linux 7.6.1-80.el7
Copyright (C) 2013 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-redhat-linux-gnu".
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>...
Reading symbols from /mnt/test...done.
[New LWP 2660]
Core was generated by `./test'.
Program terminated with signal 11, Segmentation fault.
#0  0xb75f7e5a in __memcpy_ssse3_rep () from /lib/libc.so.6
Missing separate debuginfos, use: debuginfo-install glibc-2.17-105.el7.i686 libgcc-4.8.5-4.el7.i686 libstdc++-4.8.5-4.el7.i686
(gdb) where
#0  0xb75f7e5a in __memcpy_ssse3_rep () from /lib/libc.so.6
#1  0x080484e1 in fun () at test.cpp:7
#2  0x080484ee in main () at test.cpp:12
(gdb) q

从上图可以看到，程序在main()->fun()->memcpy()处产生段错误。

转载于:https://www.cnblogs.com/abcdk/p/5682709.html