mirror of https://github.com/rust-lang/rust
55 lines
1.1 KiB
Rust
55 lines
1.1 KiB
Rust
//@ run-pass
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#![allow(dead_code)]
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use std::mem;
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// Raising alignment
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#[repr(align(16))]
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enum Align16 {
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Foo { foo: u32 },
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Bar { bar: u32 },
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}
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// Raise alignment by maximum
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#[repr(align(1), align(16))]
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#[repr(align(32))]
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#[repr(align(4))]
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enum Align32 {
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Foo,
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Bar,
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}
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// Not reducing alignment
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#[repr(align(4))]
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enum AlsoAlign16 {
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Foo { limb_with_align16: Align16 },
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Bar,
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}
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// No niche for discriminant when used as limb
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#[repr(align(16))]
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struct NoNiche16(u64, u64);
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// Discriminant will require extra space, but enum needs to stay compatible
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// with alignment 16
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#[repr(align(1))]
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enum AnotherAlign16 {
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Foo { limb_with_noniche16: NoNiche16 },
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Bar,
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Baz,
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}
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fn main() {
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assert_eq!(mem::align_of::<Align16>(), 16);
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assert_eq!(mem::size_of::<Align16>(), 16);
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assert_eq!(mem::align_of::<Align32>(), 32);
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assert_eq!(mem::size_of::<Align32>(), 32);
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assert_eq!(mem::align_of::<AlsoAlign16>(), 16);
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assert_eq!(mem::size_of::<AlsoAlign16>(), 16);
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assert_eq!(mem::align_of::<AnotherAlign16>(), 16);
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assert_eq!(mem::size_of::<AnotherAlign16>(), 32);
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}
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