arrays - 连续数组

Question

我很好奇C18标准中的一句话:

Two pointers compare equal if and only if both are null pointers, bothare pointers to the same object (including a pointer to an object anda subobject at its beginning) or function, both are pointers to onepast the last element of the same array object, or one is a pointer toone past the end of one array object and the other is a pointer to thestart of a different array object that happens to immediatelyfollow the first array object in the address space. § 6.5.9 6

为什么数组后面的对象必须是另一个数组？不能简单地成为与数组基类型相同类型的对象(例如 int 紧跟在 int[] 之后)？
难怪我试过这个代码:

#include <stdio.h>

struct test { int arr[10]; int i; };

int main() {
    struct test t;
    int *p, *q;
    p = t.arr + 10;
    q = &t.i;
    if (p == q)
        printf("Equal pointers.");
    return 0;
}

它产生相等的指针。这种行为是否根本没有保证，只是实现定义的巧合？

Answer 1

OP: Why the object following the array has to be necessarily another array?

它不是。 “...开始不同的数组...”是一种简化。下一个规范是:

For the purposes of these operators, a pointer to an object that is not an element of an array behaves the same as a pointer to the first element of an array of length one with the type of the object as its element type. C17dr § 6.5.9 7

OP: Couldn't simply be an object which type was the same as the array base type (like an int immediately following an int[])?

是的。