sizeof operands get evaluated?

Question

AFAIK sizeof doesn\'t evaluate its operands it C++.

E.g.

int x = 0;
sizeof(x += 1); // value of x is not changed

But what does this

Answer 1

I don't know much about this, but if as you say, sizeof doesn't evaluate its operand then it must just rely on the type of the expression it's used on. So I would guess that arr on its own has a different type to arr+0, and that's why it was used.