int foo(int a)
{
    switch (a)
    {
        int res;
    case 1:
        res = 1;
        return res;
    case 2:
        return res;

    default:
        return 0;
    }
}

void main()
{
    enum v1 = foo(1);    // CTFE error, v->addrOnStack not set
    enum v2 = foo(2);    // CTFE error, used before initialization
    assert(foo(2) == 0); // runtime error, res is uninitialized
}

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