Question

我想知道，如果我拿一个完全静态的类的地址，我保证其成员按正确的顺序排列吗？我想这也适用于在全局范围内定义的一组变量。

struct Buffer1
{
    static float val1;
    static float val2;
};

void readBuffer(void* buffer){ /*Do something*/}

int main()
{
// Sending the buffer
    readBuffer(&Buffer1);               // Type name is not allowed
    readBuffer(&Buffer1::val1);         // Does work, wondering if data will be correct

    return 0;
}

另外，有没有办法获取一组静态或全局变量的大小？像：

// Getting the size of the buffer
    size_t sizeOfBuffer = sizeof(Buffer1);  // Wrong size, doesn't measure static members
    sizeOfBuffer = sizeof(Buffer1::val1) + sizeof(Buffer1::val2);   // Does work but doesn't account for data padding/alignment, and is also tedious to change

我知道在这种情况下，实例化课程会更好，但我对这两个问题感到好奇。感谢。

Answer 1

不，C ++标准没有在静态范围内指定内存中对象的顺序。

C ++标准也不保证类成员的相对顺序。

如果我取其地址，静态变量是否保证有序？

1 个答案: