58 lines
831 B
Rust
58 lines
831 B
Rust
#![feature(trait_upcasting)]
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#![allow(incomplete_features)]
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trait Foo: PartialEq<i32> + std::fmt::Debug + Send + Sync {
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fn a(&self) -> i32 {
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10
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}
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fn z(&self) -> i32 {
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11
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}
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fn y(&self) -> i32 {
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12
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}
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}
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trait Bar: Foo {
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fn b(&self) -> i32 {
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20
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}
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fn w(&self) -> i32 {
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21
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}
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}
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trait Baz: Bar {
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fn c(&self) -> i32 {
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30
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}
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}
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impl Foo for i32 {
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fn a(&self) -> i32 {
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100
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}
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}
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impl Bar for i32 {
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fn b(&self) -> i32 {
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200
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}
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}
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impl Baz for i32 {
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fn c(&self) -> i32 {
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300
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}
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}
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fn main() {
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let baz: &dyn Baz = &1;
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let baz_fake: &dyn Bar = unsafe { std::mem::transmute(baz) };
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let _err = baz_fake as &dyn Foo;
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//~^ERROR: upcast on a pointer whose vtable does not match its type
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}
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