Why Does an Empty Class in C Have a Size of 1?

Understanding the Size of Empty Classes in C

In C , the size of an empty class is not zero. This might seem counterintuitive at first, but there's a crucial reason behind it.

Why the Size is Not Zero

The C standard prohibits objects and their classes from having a size of 0. This restriction prevents two distinct objects from sharing the same memory address. Even an empty class must have a size of at least 1 to ensure unique object addresses.

In the example provided:

<code class="cpp">#include <iostream>

class Test
{
};

int main()
{
    std::cout << sizeof(Test);
    return 0;
}</code>

The output is 1 because the Test class, despite being empty, has a size of 1 to comply with the standard. Every class in C , regardless of its content, must have a non-zero size to avoid potential memory address conflicts.

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