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36 lines
1.0 KiB
Rust
36 lines
1.0 KiB
Rust
//@ run-pass
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#![allow(non_upper_case_globals)]
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#![allow(dead_code)]
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/*!
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* On x86_64-linux-gnu and possibly other platforms, structs get 8-byte "preferred" alignment,
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* but their "ABI" alignment (i.e., what actually matters for data layout) is the largest alignment
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* of any field. (Also, `u64` has 8-byte ABI alignment; this is not always true).
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*
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* On such platforms, if monomorphize uses the "preferred" alignment, then it will unify
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* `A` and `B`, even though `S<A>` and `S<B>` have the field `t` at different offsets,
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* and apply the wrong instance of the method `unwrap`.
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*/
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#[derive(Copy, Clone)]
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struct S<T> { i:u8, t:T }
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impl<T> S<T> {
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fn unwrap(self) -> T {
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self.t
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}
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}
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#[derive(Copy, Clone, PartialEq, Debug)]
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struct A((u32, u32));
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#[derive(Copy, Clone, PartialEq, Debug)]
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struct B(u64);
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pub fn main() {
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static Ca: S<A> = S { i: 0, t: A((13, 104)) };
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static Cb: S<B> = S { i: 0, t: B(31337) };
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assert_eq!(Ca.unwrap(), A((13, 104)));
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assert_eq!(Cb.unwrap(), B(31337));
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}
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