gdb調試core轉儲檔案

1. 首先生成core檔案，示例代碼如下：

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

void core1()
{
    char *p = NULL;
    *p = 'a';
    printf("p:%s\n", p);
}

int main()
{
    core1();

    return 0;
}
           

[[email protected] aup]$ gcc coredump.c -o coredump -g

[[email protected] aup]$ ./coredump

段錯誤 (核心已轉儲)

[[email protected] aup]$ ll core.*

-rw-------. 1 ljq ljq 217088 5月  16 15:45 core.5004

core檔案已生成。

2. 使用gdb調試core檔案，定位錯誤位置：

[[email protected] aup]$ gdb coredump core.5004

GNU gdb (GDB) Fedora 7.10-23.fc23

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Reading symbols from coredump...done.

[New LWP 5004]

Core was generated by `./coredump'.                                                                     指出core檔案是由corddump産生

Program terminated with signal SIGSEGV, Segmentation fault.                       程式接受到信号SIGSEGV段錯誤而終止

#0  0x0804843b in core1 () at coredump.c:8                                                         程式終止時執行到coredump.c第8行，即:*p = 'a';，進而判斷執行到該行時程式異常退出

8           *p = 'a';

Missing separate debuginfos, use: dnf debuginfo-install glibc-2.22-3.fc23.i686

(gdb) bt              backtrace指令檢視函數調用棧順序

#0  0x0804843b in core1 () at coredump.c:8            最後一個被調用的函數是core1，如果有更多的函數被調用，這裡也會顯示出來

#1  0x0804846a in main () at coredump.c:14          corddump.c第14行調用core1函數

(gdb)