GDB_test_2.c

/*
* @Author: feizhao
* @Date:   2016-03-15 21:51:50
* @Last Modified by:   feizhao
* @Last Modified time: 2016-03-15 21:51:50
*/

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

struct line {
   int length;
   char contents[0]; // C99的玩法是：char contents[]; 没有指定数组长度
};

int main(){
    int this_length=10;
    struct line *thisline = (struct line *)
                     malloc (sizeof (struct line) + this_length);
    thisline->length = this_length;
    memset(thisline->contents, 'a', this_length);
    return 0;
}