Rename feature object_safe_for_dispatch to dyn_compatible_for_dispatch

This commit is contained in:
León Orell Valerian Liehr 2024-10-09 18:37:30 +02:00
parent 62b24ea7c5
commit 2e7a52b22f
No known key found for this signature in database
GPG Key ID: D17A07215F68E713
42 changed files with 130 additions and 124 deletions

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@ -154,6 +154,10 @@ declare_features! (
/// then removed. But there was no utility storing it separately, so now
/// it's in this list.
(removed, no_stack_check, "1.0.0", None, None),
/// Allows making `dyn Trait` well-formed even if `Trait` is not dyn-compatible (object safe).
/// Renamed to `dyn_compatible_for_dispatch`.
(removed, object_safe_for_dispatch, "CURRENT_RUSTC_VERSION", Some(43561),
Some("renamed to `dyn_compatible_for_dispatch`")),
/// Allows using `#[on_unimplemented(..)]` on traits.
/// (Moved to `rustc_attrs`.)
(removed, on_unimplemented, "1.40.0", None, None),

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@ -259,6 +259,14 @@ declare_features! (
(unstable, doc_notable_trait, "1.52.0", Some(45040)),
/// Allows using the `may_dangle` attribute (RFC 1327).
(unstable, dropck_eyepatch, "1.10.0", Some(34761)),
/// Allows making `dyn Trait` well-formed even if `Trait` is not dyn-compatible[^1].
/// In that case, `dyn Trait: Trait` does not hold. Moreover, coercions and
/// casts in safe Rust to `dyn Trait` for such a `Trait` is also forbidden.
///
/// Renamed from `object_safe_for_dispatch`.
///
/// [^1]: Formerly known as "object safe".
(unstable, dyn_compatible_for_dispatch, "CURRENT_RUSTC_VERSION", Some(43561)),
/// Allows using the `#[fundamental]` attribute.
(unstable, fundamental, "1.0.0", Some(29635)),
/// Allows using `#[link_name="llvm.*"]`.
@ -544,13 +552,6 @@ declare_features! (
(unstable, non_exhaustive_omitted_patterns_lint, "1.57.0", Some(89554)),
/// Allows `for<T>` binders in where-clauses
(incomplete, non_lifetime_binders, "1.69.0", Some(108185)),
/// Allows making `dyn Trait` well-formed even if `Trait` is not dyn-compatible[^1].
/// In that case, `dyn Trait: Trait` does not hold. Moreover, coercions and
/// casts in safe Rust to `dyn Trait` for such a `Trait` is also forbidden.
///
/// [^1]: Formerly known as "object safe".
// FIXME(dyn_compat_renaming): Rename feature.
(unstable, object_safe_for_dispatch, "1.40.0", Some(43561)),
/// Allows using enums in offset_of!
(unstable, offset_of_enum, "1.75.0", Some(120141)),
/// Allows using fields with slice type in offset_of!

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@ -199,7 +199,7 @@ fn check_object_overlap<'tcx>(
for component_def_id in component_def_ids {
if !tcx.is_dyn_compatible(component_def_id) {
// FIXME(dyn_compat_renaming): Rename test and update comment.
// Without the 'object_safe_for_dispatch' feature this is an error
// Without the 'dyn_compatible_for_dispatch' feature this is an error
// which will be reported by wfcheck. Ignore it here.
// This is tested by `coherence-impl-trait-for-trait-object-safe.rs`.
// With the feature enabled, the trait is not implemented automatically,

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@ -776,6 +776,7 @@ symbols! {
dropck_eyepatch,
dropck_parametricity,
dylib,
dyn_compatible_for_dispatch,
dyn_metadata,
dyn_star,
dyn_trait,

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@ -639,8 +639,8 @@ fn object_ty_for_trait<'tcx>(
/// contained by the trait object, because the object that needs to be coerced is behind
/// a pointer.
///
/// In practice, we cannot use `dyn Trait` explicitly in the obligation because it would result
/// in a new check that `Trait` is dyn-compatible, creating a cycle (until object_safe_for_dispatch
/// In practice, we cannot use `dyn Trait` explicitly in the obligation because it would result in
/// a new check that `Trait` is dyn-compatible, creating a cycle (until dyn_compatible_for_dispatch
/// is stabilized, see tracking issue <https://github.com/rust-lang/rust/issues/43561>).
/// Instead, we fudge a little by introducing a new type parameter `U` such that
/// `Self: Unsize<U>` and `U: Trait + ?Sized`, and use `U` in place of `dyn Trait`.
@ -674,7 +674,7 @@ fn receiver_is_dispatchable<'tcx>(
// the type `U` in the query
// use a bogus type parameter to mimic a forall(U) query using u32::MAX for now.
// FIXME(mikeyhew) this is a total hack. Once object_safe_for_dispatch is stabilized, we can
// FIXME(mikeyhew) this is a total hack. Once dyn_compatible_for_dispatch is stabilized, we can
// replace this with `dyn Trait`
let unsized_self_ty: Ty<'tcx> =
Ty::new_param(tcx, u32::MAX, Symbol::intern("RustaceansAreAwesome"));

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@ -881,7 +881,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
}
if let Some(principal) = data.principal() {
if !self.infcx.tcx.features().object_safe_for_dispatch {
if !self.infcx.tcx.features().dyn_compatible_for_dispatch {
principal.with_self_ty(self.tcx(), self_ty)
} else if self.tcx().is_dyn_compatible(principal.def_id()) {
principal.with_self_ty(self.tcx(), self_ty)

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@ -829,7 +829,7 @@ impl<'a, 'tcx> TypeVisitor<TyCtxt<'tcx>> for WfPredicates<'a, 'tcx> {
// obligations that don't refer to Self and
// checking those
let defer_to_coercion = tcx.features().object_safe_for_dispatch;
let defer_to_coercion = tcx.features().dyn_compatible_for_dispatch;
if !defer_to_coercion {
if let Some(principal) = data.principal_def_id() {

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@ -1,6 +1,6 @@
//@ known-bug: #120241
//@ edition:2021
#![feature(object_safe_for_dispatch)]
#![feature(dyn_compatible_for_dispatch)]
#![feature(unsized_fn_params)]
fn guard(_s: Copy) -> bool {

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@ -1,6 +1,6 @@
//@ known-bug: #120241
//@ edition:2021
#![feature(object_safe_for_dispatch)]
#![feature(dyn_compatible_for_dispatch)]
trait B {
fn f(a: A) -> A;

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@ -1,6 +1,6 @@
//@ known-bug: #120482
//@ edition:2021
#![feature(object_safe_for_dispatch)]
#![feature(dyn_compatible_for_dispatch)]
trait B {
fn bar(&self, x: &Self);

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@ -1,6 +1,6 @@
//@ known-bug: rust-lang/rust#125512
//@ edition:2021
#![feature(object_safe_for_dispatch)]
#![feature(dyn_compatible_for_dispatch)]
trait B {
fn f(a: A) -> A;
}

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@ -1,7 +1,7 @@
//@ known-bug: rust-lang/rust#128176
#![feature(generic_const_exprs)]
#![feature(object_safe_for_dispatch)]
#![feature(dyn_compatible_for_dispatch)]
trait X {
type Y<const N: i16>;
}

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@ -1,6 +1,6 @@
//@ known-bug: #130521
#![feature(object_safe_for_dispatch)]
#![feature(dyn_compatible_for_dispatch)]
struct Vtable(dyn Cap);
trait Cap<'a> {}

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@ -1,7 +1,7 @@
// Check that unsafe trait object do not implement themselves
// automatically
#![feature(object_safe_for_dispatch)]
#![feature(dyn_compatible_for_dispatch)]
trait Trait: Sized {
fn call(&self);

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@ -0,0 +1,41 @@
// Test that the use of the dyn-incompatible trait objects
// are gated by the `dyn_compatible_for_dispatch` feature gate.
trait DynIncompatible1: Sized {}
trait DynIncompatible2 {
fn static_fn() {}
}
trait DynIncompatible3 {
fn foo<T>(&self);
}
trait DynIncompatible4 {
fn foo(&self, s: &Self);
}
fn takes_non_object_safe_ref<T>(obj: &dyn DynIncompatible1) {
//~^ ERROR E0038
}
fn return_non_object_safe_ref() -> &'static dyn DynIncompatible2 {
//~^ ERROR E0038
loop {}
}
fn takes_non_object_safe_box(obj: Box<dyn DynIncompatible3>) {
//~^ ERROR E0038
}
fn return_non_object_safe_rc() -> std::rc::Rc<dyn DynIncompatible4> {
//~^ ERROR E0038
loop {}
}
trait Trait {}
impl Trait for dyn DynIncompatible1 {}
//~^ ERROR E0038
fn main() {}

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@ -1,28 +1,28 @@
error[E0038]: the trait `NonObjectSafe1` cannot be made into an object
--> $DIR/feature-gate-object_safe_for_dispatch.rs:18:39
error[E0038]: the trait `DynIncompatible1` cannot be made into an object
--> $DIR/feature-gate-dyn_compatible_for_dispatch.rs:18:39
|
LL | fn takes_non_object_safe_ref<T>(obj: &dyn NonObjectSafe1) {
| ^^^^^^^^^^^^^^^^^^ `NonObjectSafe1` cannot be made into an object
LL | fn takes_non_object_safe_ref<T>(obj: &dyn DynIncompatible1) {
| ^^^^^^^^^^^^^^^^^^^^ `DynIncompatible1` cannot be made into an object
|
note: for a trait to be "dyn-compatible" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>
--> $DIR/feature-gate-object_safe_for_dispatch.rs:4:23
--> $DIR/feature-gate-dyn_compatible_for_dispatch.rs:4:25
|
LL | trait NonObjectSafe1: Sized {}
| -------------- ^^^^^ ...because it requires `Self: Sized`
LL | trait DynIncompatible1: Sized {}
| ---------------- ^^^^^ ...because it requires `Self: Sized`
| |
| this trait cannot be made into an object...
error[E0038]: the trait `NonObjectSafe2` cannot be made into an object
--> $DIR/feature-gate-object_safe_for_dispatch.rs:22:45
error[E0038]: the trait `DynIncompatible2` cannot be made into an object
--> $DIR/feature-gate-dyn_compatible_for_dispatch.rs:22:45
|
LL | fn return_non_object_safe_ref() -> &'static dyn NonObjectSafe2 {
| ^^^^^^^^^^^^^^^^^^ `NonObjectSafe2` cannot be made into an object
LL | fn return_non_object_safe_ref() -> &'static dyn DynIncompatible2 {
| ^^^^^^^^^^^^^^^^^^^^ `DynIncompatible2` cannot be made into an object
|
note: for a trait to be "dyn-compatible" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>
--> $DIR/feature-gate-object_safe_for_dispatch.rs:7:8
--> $DIR/feature-gate-dyn_compatible_for_dispatch.rs:7:8
|
LL | trait NonObjectSafe2 {
| -------------- this trait cannot be made into an object...
LL | trait DynIncompatible2 {
| ---------------- this trait cannot be made into an object...
LL | fn static_fn() {}
| ^^^^^^^^^ ...because associated function `static_fn` has no `self` parameter
help: consider turning `static_fn` into a method by giving it a `&self` argument
@ -34,47 +34,47 @@ help: alternatively, consider constraining `static_fn` so it does not apply to t
LL | fn static_fn() where Self: Sized {}
| +++++++++++++++++
error[E0038]: the trait `NonObjectSafe3` cannot be made into an object
--> $DIR/feature-gate-object_safe_for_dispatch.rs:27:39
error[E0038]: the trait `DynIncompatible3` cannot be made into an object
--> $DIR/feature-gate-dyn_compatible_for_dispatch.rs:27:39
|
LL | fn takes_non_object_safe_box(obj: Box<dyn NonObjectSafe3>) {
| ^^^^^^^^^^^^^^^^^^ `NonObjectSafe3` cannot be made into an object
LL | fn takes_non_object_safe_box(obj: Box<dyn DynIncompatible3>) {
| ^^^^^^^^^^^^^^^^^^^^ `DynIncompatible3` cannot be made into an object
|
note: for a trait to be "dyn-compatible" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>
--> $DIR/feature-gate-object_safe_for_dispatch.rs:11:8
--> $DIR/feature-gate-dyn_compatible_for_dispatch.rs:11:8
|
LL | trait NonObjectSafe3 {
| -------------- this trait cannot be made into an object...
LL | trait DynIncompatible3 {
| ---------------- this trait cannot be made into an object...
LL | fn foo<T>(&self);
| ^^^ ...because method `foo` has generic type parameters
= help: consider moving `foo` to another trait
error[E0038]: the trait `NonObjectSafe4` cannot be made into an object
--> $DIR/feature-gate-object_safe_for_dispatch.rs:31:47
error[E0038]: the trait `DynIncompatible4` cannot be made into an object
--> $DIR/feature-gate-dyn_compatible_for_dispatch.rs:31:47
|
LL | fn return_non_object_safe_rc() -> std::rc::Rc<dyn NonObjectSafe4> {
| ^^^^^^^^^^^^^^^^^^ `NonObjectSafe4` cannot be made into an object
LL | fn return_non_object_safe_rc() -> std::rc::Rc<dyn DynIncompatible4> {
| ^^^^^^^^^^^^^^^^^^^^ `DynIncompatible4` cannot be made into an object
|
note: for a trait to be "dyn-compatible" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>
--> $DIR/feature-gate-object_safe_for_dispatch.rs:15:22
--> $DIR/feature-gate-dyn_compatible_for_dispatch.rs:15:22
|
LL | trait NonObjectSafe4 {
| -------------- this trait cannot be made into an object...
LL | trait DynIncompatible4 {
| ---------------- this trait cannot be made into an object...
LL | fn foo(&self, s: &Self);
| ^^^^^ ...because method `foo` references the `Self` type in this parameter
= help: consider moving `foo` to another trait
error[E0038]: the trait `NonObjectSafe1` cannot be made into an object
--> $DIR/feature-gate-object_safe_for_dispatch.rs:38:16
error[E0038]: the trait `DynIncompatible1` cannot be made into an object
--> $DIR/feature-gate-dyn_compatible_for_dispatch.rs:38:16
|
LL | impl Trait for dyn NonObjectSafe1 {}
| ^^^^^^^^^^^^^^^^^^ `NonObjectSafe1` cannot be made into an object
LL | impl Trait for dyn DynIncompatible1 {}
| ^^^^^^^^^^^^^^^^^^^^ `DynIncompatible1` cannot be made into an object
|
note: for a trait to be "dyn-compatible" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>
--> $DIR/feature-gate-object_safe_for_dispatch.rs:4:23
--> $DIR/feature-gate-dyn_compatible_for_dispatch.rs:4:25
|
LL | trait NonObjectSafe1: Sized {}
| -------------- ^^^^^ ...because it requires `Self: Sized`
LL | trait DynIncompatible1: Sized {}
| ---------------- ^^^^^ ...because it requires `Self: Sized`
| |
| this trait cannot be made into an object...

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@ -1,41 +0,0 @@
// Test that the use of the non object-safe trait objects
// are gated by `object_safe_for_dispatch` feature gate.
trait NonObjectSafe1: Sized {}
trait NonObjectSafe2 {
fn static_fn() {}
}
trait NonObjectSafe3 {
fn foo<T>(&self);
}
trait NonObjectSafe4 {
fn foo(&self, s: &Self);
}
fn takes_non_object_safe_ref<T>(obj: &dyn NonObjectSafe1) {
//~^ ERROR E0038
}
fn return_non_object_safe_ref() -> &'static dyn NonObjectSafe2 {
//~^ ERROR E0038
loop {}
}
fn takes_non_object_safe_box(obj: Box<dyn NonObjectSafe3>) {
//~^ ERROR E0038
}
fn return_non_object_safe_rc() -> std::rc::Rc<dyn NonObjectSafe4> {
//~^ ERROR E0038
loop {}
}
trait Trait {}
impl Trait for dyn NonObjectSafe1 {}
//~^ ERROR E0038
fn main() {}

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@ -1,8 +1,8 @@
// Test that Copy bounds inherited by trait are checked.
//
//@ revisions: curr object_safe_for_dispatch
//@ revisions: curr dyn_compatible_for_dispatch
#![cfg_attr(object_safe_for_dispatch, feature(object_safe_for_dispatch))]
#![cfg_attr(dyn_compatible_for_dispatch, feature(dyn_compatible_for_dispatch))]
use std::any::Any;
@ -19,7 +19,7 @@ fn take_param<T:Foo>(foo: &T) { }
fn a() {
let x: Box<_> = Box::new(3);
take_param(&x); //[curr]~ ERROR E0277
//[object_safe_for_dispatch]~^ ERROR E0277
//[dyn_compatible_for_dispatch]~^ ERROR E0277
}
fn b() {
@ -28,7 +28,7 @@ fn b() {
let z = &x as &dyn Foo;
//[curr]~^ ERROR E0038
//[curr]~| ERROR E0038
//[object_safe_for_dispatch]~^^^ ERROR E0038
//[dyn_compatible_for_dispatch]~^^^ ERROR E0038
}
fn main() { }

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@ -1,9 +1,9 @@
// Check that we correctly prevent users from making trait objects
// from traits with associated consts.
//
//@ revisions: curr object_safe_for_dispatch
//@ revisions: curr dyn_compatible_for_dispatch
#![cfg_attr(object_safe_for_dispatch, feature(object_safe_for_dispatch))]
#![cfg_attr(dyn_compatible_for_dispatch, feature(dyn_compatible_for_dispatch))]
trait Bar {
const X: usize;

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@ -1,9 +1,9 @@
// Check that we correctly prevent users from making trait objects
// from traits with generic methods, unless `where Self : Sized` is
// present.
//@ revisions: curr object_safe_for_dispatch
//@ revisions: curr dyn_compatible_for_dispatch
#![cfg_attr(object_safe_for_dispatch, feature(object_safe_for_dispatch))]
#![cfg_attr(dyn_compatible_for_dispatch, feature(dyn_compatible_for_dispatch))]
trait Bar {
@ -18,14 +18,14 @@ trait Quux {
fn make_bar<T:Bar>(t: &T) -> &dyn Bar {
//[curr]~^ ERROR E0038
t
//[object_safe_for_dispatch]~^ ERROR E0038
//[dyn_compatible_for_dispatch]~^ ERROR E0038
//[curr]~^^ ERROR E0038
}
fn make_bar_explicit<T:Bar>(t: &T) -> &dyn Bar {
//[curr]~^ ERROR E0038
t as &dyn Bar
//[object_safe_for_dispatch]~^ ERROR E0038
//[dyn_compatible_for_dispatch]~^ ERROR E0038
//[curr]~^^ ERROR E0038
//[curr]~| ERROR E0038
}

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@ -2,9 +2,9 @@
// form traits that make use of `Self` in an argument or return
// position, unless `where Self : Sized` is present..
//
//@ revisions: curr object_safe_for_dispatch
//@ revisions: curr dyn_compatible_for_dispatch
#![cfg_attr(object_safe_for_dispatch, feature(object_safe_for_dispatch))]
#![cfg_attr(dyn_compatible_for_dispatch, feature(dyn_compatible_for_dispatch))]
trait Bar {

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@ -1,9 +1,9 @@
// Check that we correctly prevent users from making trait objects
// from traits with static methods.
//
//@ revisions: curr object_safe_for_dispatch
//@ revisions: curr dyn_compatible_for_dispatch
#![cfg_attr(object_safe_for_dispatch, feature(object_safe_for_dispatch))]
#![cfg_attr(dyn_compatible_for_dispatch, feature(dyn_compatible_for_dispatch))]
trait Foo {
fn foo() {}

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@ -1,9 +1,9 @@
// Check that we correctly prevent users from making trait objects
// from traits where `Self : Sized`.
//
//@ revisions: curr object_safe_for_dispatch
//@ revisions: curr dyn_compatible_for_dispatch
#![cfg_attr(object_safe_for_dispatch, feature(object_safe_for_dispatch))]
#![cfg_attr(dyn_compatible_for_dispatch, feature(dyn_compatible_for_dispatch))]
trait Bar
where Self : Sized

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@ -1,9 +1,9 @@
// Check that we correctly prevent users from making trait objects
// from traits where `Self : Sized`.
//
//@ revisions: curr object_safe_for_dispatch
//@ revisions: curr dyn_compatible_for_dispatch
#![cfg_attr(object_safe_for_dispatch, feature(object_safe_for_dispatch))]
#![cfg_attr(dyn_compatible_for_dispatch, feature(dyn_compatible_for_dispatch))]
trait Bar: Sized {
fn bar<T>(&self, t: T);

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@ -3,7 +3,7 @@
//
//@ check-pass
#![feature(object_safe_for_dispatch)]
#![feature(dyn_compatible_for_dispatch)]
trait Trait: Sized {}

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@ -5,7 +5,7 @@
//@[next] compile-flags: -Znext-solver
//@ run-pass
#![feature(object_safe_for_dispatch)]
#![feature(dyn_compatible_for_dispatch)]
trait Bad {
fn stat() -> char {

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@ -3,7 +3,7 @@
//
//@ check-pass
#![feature(object_safe_for_dispatch)]
#![feature(dyn_compatible_for_dispatch)]
trait Statics {
fn plain() {}

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@ -1,6 +1,6 @@
//@ revisions: curr object_safe_for_dispatch
//@ revisions: curr dyn_compatible_for_dispatch
#![cfg_attr(object_safe_for_dispatch, feature(object_safe_for_dispatch))]
#![cfg_attr(dyn_compatible_for_dispatch, feature(dyn_compatible_for_dispatch))]
use std::rc::Rc;
@ -33,7 +33,7 @@ fn make_foo() {
let x = Rc::new(5usize) as Rc<dyn Foo>;
//[curr]~^ ERROR E0038
//[curr]~| ERROR E0038
//[object_safe_for_dispatch]~^^^ ERROR E0038
//[dyn_compatible_for_dispatch]~^^^ ERROR E0038
}
fn make_bar() {

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@ -1,4 +1,4 @@
#![feature(object_safe_for_dispatch)]
#![feature(dyn_compatible_for_dispatch)]
trait Foo {
fn f() {}

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@ -1,7 +1,7 @@
// Check that we do not allow casts or coercions
// to object unsafe trait objects inside a Box
#![feature(object_safe_for_dispatch)]
#![feature(dyn_compatible_for_dispatch)]
trait Trait: Sized {}

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@ -1,7 +1,7 @@
// Check that we do not allow casts or coercions
// to object unsafe trait objects by ref
#![feature(object_safe_for_dispatch)]
#![feature(dyn_compatible_for_dispatch)]
trait Trait: Sized {}

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@ -1,7 +1,7 @@
// Check that we do not allow coercions to object
// unsafe trait objects in match arms
#![feature(object_safe_for_dispatch)]
#![feature(dyn_compatible_for_dispatch)]
trait Trait: Sized {}