如何在C＆C ++中查找细分错误？（使用GDB）

分段错误是运行时错误之一，它是由于内存访问冲突引起的，例如访问无效的数组索引，指向一些受限地址等。在本文中，我们将看到如何使用GDB工具检测这种类型的错误。。

让我们看一下代码和找到错误的相应步骤。

示例

#include <stdio.h>
main() {
   int* ptr = NULL;
   *ptr = 1; //trying to access unknown memory location
   printf("%p\n", ptr);
}

使用“ gcc –g program_name.c”编译代码，然后使用“ ./a.out”运行

输出结果

soumyadeep@soumyadeep-VirtualBox:~/Cpp_progs$ ./a.out
Segmentation fault (core dumped)

发生细分错误。

写'gdb ./a.out core'

soumyadeep@soumyadeep-VirtualBox:~/Cpp_progs$ gdb ./a.out core

GNU gdb (Ubuntu 8.1-0ubuntu3) 8.1.0.20180409-git

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-linux-gnu".

Type "show configuration" for configuration details.

For bug reporting instructions, please see:

<http://www.gnu.org/software/gdb/bugs/>.

Find the GDB manual and other documentation resources online at:

<http://www.gnu.org/software/gdb/documentation/>.

For help, type "help".

Type "apropos word" to search for commands related to "word"...

Reading symbols from ./a.out...done.

/home/soumyadeep/Cpp_progs/core: No such file or directory.

(gdb)

输入“ r”，然后按Enter。

Starting program: /home/soumyadeep/Cpp_progs/a.out

Program received signal SIGSEGV, Segmentation fault.

0x000055555555465e in main () at 1230.find_seg_error.c:5

5 *ptr = 1; //trying to access unknown memory location

(gdb)

这样我们就成功得到了错误，现在退出GDB

(gdb) quit
A debugging session is active.
Inferior 1 [process 2794] will be killed.
Quit anyway? (y or n) y