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//@ check-fail
#![feature(extern_types)]
#![feature(pointer_like_trait)]
use std::marker::PointerLike;
struct NotReprTransparent;
impl PointerLike for NotReprTransparent {}
//~^ ERROR: implementation must be applied to type that
//~| NOTE: the struct `NotReprTransparent` is not `repr(transparent)`
#[repr(transparent)]
struct FieldIsPl(usize);
impl PointerLike for FieldIsPl {}
#[repr(transparent)]
struct FieldIsPlAndHasOtherField(usize, ());
impl PointerLike for FieldIsPlAndHasOtherField {}
#[repr(transparent)]
struct FieldIsNotPl(u8);
impl PointerLike for FieldIsNotPl {}
//~^ ERROR: implementation must be applied to type that
//~| NOTE: the field `0` of struct `FieldIsNotPl` does not implement `PointerLike`
#[repr(transparent)]
struct GenericFieldIsNotPl<T>(T);
impl<T> PointerLike for GenericFieldIsNotPl<T> {}
//~^ ERROR: implementation must be applied to type that
//~| NOTE: the field `0` of struct `GenericFieldIsNotPl<T>` does not implement `PointerLike`
#[repr(transparent)]
struct GenericFieldIsPl<T>(T);
impl<T: PointerLike> PointerLike for GenericFieldIsPl<T> {}
#[repr(transparent)]
struct IsZeroSized(());
impl PointerLike for IsZeroSized {}
//~^ ERROR: implementation must be applied to type that
//~| NOTE: the struct `IsZeroSized` is `repr(transparent)`, but does not have a non-trivial field
trait SomeTrait {}
impl PointerLike for dyn SomeTrait {}
//~^ ERROR: implementation must be applied to type that
//~| NOTE: types of dynamic or unknown size
extern "C" {
type ExternType;
}
impl PointerLike for ExternType {}
//~^ ERROR: implementation must be applied to type that
//~| NOTE: types of dynamic or unknown size
struct LocalSizedType(&'static str);
struct LocalUnsizedType(str);
// This is not a special error but a normal coherence error,
// which should still happen.
impl PointerLike for &LocalSizedType {}
//~^ ERROR: conflicting implementations of trait `PointerLike`
//~| NOTE: conflicting implementation in crate `core`
impl PointerLike for &LocalUnsizedType {}
//~^ ERROR: implementation must be applied to type that
//~| NOTE: references to dynamically-sized types are too large to be `PointerLike`
impl PointerLike for Box<LocalSizedType> {}
//~^ ERROR: conflicting implementations of trait `PointerLike`
//~| NOTE: conflicting implementation in crate `alloc`
impl PointerLike for Box<LocalUnsizedType> {}
//~^ ERROR: implementation must be applied to type that
//~| NOTE: boxes of dynamically-sized types are too large to be `PointerLike`
fn expects_pointer_like(x: impl PointerLike) {}
fn main() {
expects_pointer_like(FieldIsPl(1usize));
expects_pointer_like(FieldIsPlAndHasOtherField(1usize, ()));
expects_pointer_like(GenericFieldIsPl(1usize));
}
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