相关疑难解决方法(0)

我以为我真的理解这一点,并重新阅读标准(ISO 9899:1990)只是证实了我明显错误的理解,所以现在我问这里.

以下程序崩溃:

#include <stdio.h>
#include <stddef.h>

typedef struct {
    int array[3];
} type1_t;

typedef struct {
    int *ptr;
} type2_t;

type1_t my_test = { {1, 2, 3} };

int main(int argc, char *argv[])
{
    (void)argc;
    (void)argv;

    type1_t *type1_p =             &my_test;
    type2_t *type2_p = (type2_t *) &my_test;

    printf("offsetof(type1_t, array) = %lu\n", offsetof(type1_t, array)); // 0
    printf("my_test.array[0]  = %d\n", my_test.array[0]);
    printf("type1_p->array[0] = %d\n", type1_p->array[0]);
    printf("type2_p->ptr[0]   = %d\n", type2_p->ptr[0]);  // this line crashes

    return 0;
}

比较表达式my_test.array[0]并type2_p->ptr[0]根据我对标准的解释:

6.3.2.1数组下标 …