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From: "18307130172 at fudan dot edu.cn" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug tree-optimization/106131] [10/11/12/13 Regression]
 -fstrict-aliasing breaks normal program that does not use any pointer or
 reference
Date: Thu, 30 Jun 2022 00:50:45 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D106131

--- Comment #6 from Xue Zhenliang <18307130172 at fudan dot edu.cn> ---
I'm trying to reducing it further. Now I've eliminated the dependency on ST=
L:

struct Pair {
    int a, b;

    Pair(const Pair &) =3D default;
    Pair(int _a, int _b) : a(_a), b(_b) {}
    Pair &operator=3D(const Pair &z) {
        a =3D z.a;
        b =3D z.b;
        return *this;
    }
};

const int &max(const int &a, const int &b) {
    return a < b ? b : a;
}

int foo(Pair x, Pair y) {
    return max(x.b, y.b);
}

int main() {
    auto f =3D new Pair[3] {{0, -11}, {0, -8}, {0, 2}};
    for (int i =3D 0; i < 1; i++) {
        f[i] =3D f[0];
        if(i =3D=3D 0)
            f[i] =3D f[2];
        if (foo(f[i], f[1]) !=3D 2)
            __builtin_abort();
    }
}=