我试图在我的程序中添加一个断点
b {line number}
但是我总是发现错误:
No symbol table is loaded. Use the "file" command.
我该怎么办?
解决方法
这是gdb的快速入门教程:
/* test.c */ /* Sample program to debug. */ #include <stdio.h> #include <stdlib.h> int main (int argc,char **argv) { if (argc != 3) return 1; int a = atoi (argv[1]); int b = atoi (argv[2]); int c = a + b; printf ("%d\n",c); return 0; }
编译-g选项:
gcc -g -o test test.c
将现在包含调试符号的可执行文件加载到gdb中:
gdb --annotate=3 test.exe
现在你应该在gdb提示符下找到自己.在那里可以向gdb发出命令.
假设您希望在第11行放置断点,并执行执行,打印局部变量的值 – 以下命令序列将帮助您执行此操作:
(gdb) break test.c:11 Breakpoint 1 at 0x401329: file test.c,line 11. (gdb) set args 10 20 (gdb) run Starting program: c:\Documents and Settings\VMathew\Desktop/test.exe 10 20 [New thread 3824.0x8e8] Breakpoint 1,main (argc=3,argv=0x3d5a90) at test.c:11 (gdb) n (gdb) print a $1 = 10 (gdb) n (gdb) print b $2 = 20 (gdb) n (gdb) print c $3 = 30 (gdb) c Continuing. 30 Program exited normally. (gdb)
简而言之,您需要使用以下命令来开始使用gdb:
break file:lineno - sets a breakpoint in the file at lineno. set args - sets the command line arguments. run - executes the debugged program with the given command line arguments. next (n) and step (s) - step program and step program until it reaches a different source line,respectively. print - prints a local variable bt - print backtrace of all stack frames c - continue execution.