const violation?

[H. S. Teoh]

Why does the following code compile?

        import std.stdio;
        int f(ref int x) {
                return x++;
        }
        class A {
                int x=123;
                int g() const {
                        return f(x);
                }
        }
        void main() {
                auto a = new A;
                writeln(a.g());
                writeln(a.g());
        }

Shouldn't the const member g() be prohibited from passing a ref to a
member variable to f()?

But this code not only compiles, it outputs:

        123
        124

So I've managed to call a const member of A to alter the value of A.x?
Am I misunderstanding the meaning of const when applied to a member
function, or is this a compiler bug?

P.S. I'm using gdc-4.6; does dmd also have this behaviour?


T

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