68 lines
1.5 KiB
Rust
68 lines
1.5 KiB
Rust
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// run-pass
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#![allow(dead_code)]
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struct Foo<T: ?Sized> {
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a: u16,
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b: T
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}
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trait Bar {
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fn get(&self) -> usize;
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}
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impl Bar for usize {
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fn get(&self) -> usize { *self }
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}
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struct Baz<T: ?Sized> {
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a: T
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}
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struct HasDrop<T: ?Sized> {
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ptr: Box<usize>,
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data: T
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}
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fn main() {
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// Test that zero-offset works properly
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let b : Baz<usize> = Baz { a: 7 };
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assert_eq!(b.a.get(), 7);
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let b : &Baz<dyn Bar> = &b;
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assert_eq!(b.a.get(), 7);
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// Test that the field is aligned properly
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let f : Foo<usize> = Foo { a: 0, b: 11 };
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assert_eq!(f.b.get(), 11);
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let ptr1 : *const u8 = &f.b as *const _ as *const u8;
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let f : &Foo<dyn Bar> = &f;
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let ptr2 : *const u8 = &f.b as *const _ as *const u8;
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assert_eq!(f.b.get(), 11);
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// The pointers should be the same
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assert_eq!(ptr1, ptr2);
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// Test that nested DSTs work properly
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let f : Foo<Foo<usize>> = Foo { a: 0, b: Foo { a: 1, b: 17 }};
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assert_eq!(f.b.b.get(), 17);
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let f : &Foo<Foo<dyn Bar>> = &f;
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assert_eq!(f.b.b.get(), 17);
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// Test that get the pointer via destructuring works
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let f : Foo<usize> = Foo { a: 0, b: 11 };
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let f : &Foo<dyn Bar> = &f;
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let &Foo { a: _, b: ref bar } = f;
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assert_eq!(bar.get(), 11);
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// Make sure that drop flags don't screw things up
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let d : HasDrop<Baz<[i32; 4]>> = HasDrop {
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ptr: Box::new(0),
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data: Baz { a: [1,2,3,4] }
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};
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assert_eq!([1,2,3,4], d.data.a);
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let d : &HasDrop<Baz<[i32]>> = &d;
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assert_eq!(&[1,2,3,4], &d.data.a);
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}
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