编写一个必然crash 的程序
#include <stdio.h> void crash(){ char *a=0; *a=0; } int main() { printf("hello world\n"); crash(); printf("after crash\n"); }
执行gdb 远程调试
gdbserver :1234 a.out
运行 gdb , 运行命令 target remote :1234
必须用 file 指定可执行文件,才能看见调用函数
(gdb) c Continuing. Program received signal SIGSEGV, Segmentation fault. 0x0000000000400534 in ?? () (gdb) bt #0 0x0000000000400534 in ?? () #1 0x00007fffffffe4c0 in ?? () #2 0x000000000040054c in ?? () #3 0x0000000000000000 in ?? () (gdb) file /home/payne/hello/a.out A program is being debugged already. Are you sure you want to change the file? (y or n) y Reading symbols from /home/payne/hello/a.out...done. (gdb) bt #0 0x0000000000400534 in fun1 () at hello.cpp:6 #1 0x000000000040054c in main () at hello.cpp:12
不用 -g 编译也能看见函数,但不能定位到行
Program received signal SIGSEGV, Segmentation fault. 0x0000000000400534 in crash() () (gdb) bt #0 0x0000000000400534 in crash() () #1 0x000000000040054c in main ()
把 crash 放到 so 中会如何?
生成libcrash.so 重新编译 hello.cpp
g++ -o libcrash.so -shared crash.cpp
export LD_LIBRARY_PATH=`pwd`
g++ hello.cpp -lcrash
gdb 不能定位到 so 中的函数
rogram received signal SIGSEGV, Segmentation fault. 0x00007ffff7ff65bc in ?? () (gdb) bt #0 0x00007ffff7ff65bc in ?? () #1 0x00007fffffffe470 in ?? () #2 0x0000000000400657 in ?? () #3 0x0000000000000000 in ?? () (gdb) file /home/payne/hello/a.out A program is being debugged already. Are you sure you want to change the file? (y or n) Please answer y or n. A program is being debugged already. Are you sure you want to change the file? (y or n) y Reading symbols from /home/payne/hello/a.out...(no debugging symbols found)...done. (gdb) bty Undefined command: "bty". Try "help". (gdb) bt #0 0x00007ffff7ff65bc in ?? () #1 0x00007fffffffe470 in ?? () #2 0x0000000000400657 in main ()
用 set solib-search-path 指定路径, 可以得到 so 中的位置
(gdb) set solib-search-path /home/payne/hello Reading symbols from /home/payne/hello/libcrash.so...(no debugging symbols found)...done. Loaded symbols for /home/payne/hello/libcrash.so Reading symbols from /lib/x86_64-linux-gnu/libc.so.6...Reading symbols from /usr/lib/debug/lib/x86_64-linux-gnu/libc-2.15.so...done. done. Loaded symbols for /lib/x86_64-linux-gnu/libc.so.6 Reading symbols from /lib64/ld-linux-x86-64.so.2...Reading symbols from /usr/lib/debug/lib/x86_64-linux-gnu/ld-2.15.so...done. done. Loaded symbols for /lib64/ld-linux-x86-64.so.2 (gdb) bt #0 0x00007ffff7ff65bc in crash() () from /home/payne/hello/libcrash.so #1 0x0000000000400657 in main ()
gdbserver 远程调试问题:设置文件和so搜索路径
时间: 2024-10-19 14:03:14