59 lines
1.4 KiB
Rust
59 lines
1.4 KiB
Rust
// revisions: nofallback fallback
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// only-windows - the number of `Error` impls is platform-dependent
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//[fallback] check-pass
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//[nofallback] check-fail
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#![feature(never_type)]
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#![cfg_attr(fallback, feature(never_type_fallback))]
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#![allow(unreachable_code)]
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use std::error::Error;
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use std::mem;
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fn raw_ptr_box<T>(t: T) -> *mut T {
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panic!()
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}
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fn foo(x: !) -> Box<dyn Error> {
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/* *mut $0 is coerced to Box<dyn Error> here */ Box::<_ /* ! */>::new(x)
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//[nofallback]~^ ERROR trait bound `(): std::error::Error` is not satisfied
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}
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fn foo_raw_ptr(x: !) -> *mut dyn Error {
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/* *mut $0 is coerced to *mut Error here */ raw_ptr_box::<_ /* ! */>(x)
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//[nofallback]~^ ERROR trait bound `(): std::error::Error` is not satisfied
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}
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fn no_coercion(d: *mut dyn Error) -> *mut dyn Error {
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/* an unsize coercion won't compile here, and it is indeed not used
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because there is nothing requiring the _ to be Sized */
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d as *mut _
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}
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trait Xyz {}
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struct S;
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struct T;
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impl Xyz for S {}
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impl Xyz for T {}
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fn foo_no_never() {
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let mut x /* : Option<S> */ = None;
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let mut first_iter = false;
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loop {
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if !first_iter {
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let y: Box<dyn Xyz>
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= /* Box<$0> is coerced to Box<Xyz> here */ Box::new(x.unwrap());
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}
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x = Some(S);
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first_iter = true;
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}
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let mut y : Option<S> = None;
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// assert types are equal
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mem::swap(&mut x, &mut y);
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}
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fn main() {
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}
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