File: double_check2.rs

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rustc 1.88.0%2Bdfsg1-1
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//@ check-pass

// This test exhibits undefined behavior, but it is very expensive and complex to check for such
// UB in constants.
// Thus, we do not detect it if you create references to statics in ways that are UB.

enum Foo {
    A = 5,
    B = 42,
}
enum Bar {
    C = 42,
    D = 99,
}
#[repr(C)]
union Union {
    foo: &'static Foo,
    bar: &'static Bar,
    u8: &'static u8,
}
static BAR: u8 = 5;
static FOO: (&Foo, &Bar) = unsafe {
    (
        // undefined behavior
        Union { u8: &BAR }.foo,
        Union { u8: &BAR }.bar,
    )
};
static FOO2: (&Foo, &Bar) = unsafe { (std::mem::transmute(&BAR), std::mem::transmute(&BAR)) };
//^ undefined behavior

fn main() {}