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Use BikeshedGuaranteedNotDrop in unsafe binder type WF too

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This commit is contained in:
Michael Goulet 2025-02-06 21:19:21 +00:00
parent 516afd557c
commit d0564fda65
4 changed files with 43 additions and 81 deletions
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2
compiler/rustc_next_trait_solver/src/solve/trait_goals.rs
View file

@ -627,7 +627,7 @@ where
/// NOTE: This is implemented as a built-in goal and not a set of impls like:
///
/// ```
/// ```rust,ignore (illustrative)
/// impl<T> BikeshedGuaranteedNoDrop for T where T: Copy {}
/// impl<T> BikeshedGuaranteedNoDrop for ManuallyDrop<T> {}
/// ```

5
compiler/rustc_trait_selection/src/traits/wf.rs
View file

@ -881,7 +881,10 @@ impl<'a, 'tcx> TypeVisitor<TyCtxt<'tcx>> for WfPredicates<'a, 'tcx> {
ty.map_bound(|ty| {
ty::TraitRef::new(
self.tcx(),
self.tcx().require_lang_item(LangItem::Copy, Some(self.span)),
self.tcx().require_lang_item(
LangItem::BikeshedGuaranteedNoDrop,
Some(self.span),
),
[ty],
)
}),

24
tests/ui/unsafe-binders/moves.rs
View file

@ -1,40 +1,40 @@
//@ known-bug: unknown
#![feature(unsafe_binders)]
// FIXME(unsafe_binders) ~^ WARN the feature `unsafe_binders` is incomplete
//~^ WARN the feature `unsafe_binders` is incomplete
use std::unsafe_binder::{wrap_binder, unwrap_binder};
use std::mem::{drop, ManuallyDrop};
use std::mem::{ManuallyDrop, drop};
use std::unsafe_binder::{unwrap_binder, wrap_binder};
#[derive(Default)]
struct NotCopyInner;
type NotCopy = ManuallyDrop<NotCopyInner>;
fn use_after_wrap() {
unsafe {
let base = NotCopy;
let base = NotCopy::default();
let binder: unsafe<> NotCopy = wrap_binder!(base);
drop(base);
// FIXME(unsafe_binders) ~^ ERROR use of moved value: `base`
//~^ ERROR use of moved value: `base`
}
}
fn move_out_of_wrap() {
unsafe {
let binder: unsafe<> NotCopy = wrap_binder!(NotCopy);
let binder: unsafe<> NotCopy = wrap_binder!(NotCopy::default());
drop(unwrap_binder!(binder));
drop(unwrap_binder!(binder));
// FIXME(unsafe_binders) ~^ ERROR use of moved value: `binder`
//~^ ERROR use of moved value: `binder`
}
}
fn not_conflicting() {
unsafe {
let binder: unsafe<> (NotCopy, NotCopy) = wrap_binder!((NotCopy, NotCopy));
let binder: unsafe<> (NotCopy, NotCopy) =
wrap_binder!((NotCopy::default(), NotCopy::default()));
drop(unwrap_binder!(binder).0);
drop(unwrap_binder!(binder).1);
// ^ NOT a problem.
// ^ NOT a problem, since the moves are disjoint.
drop(unwrap_binder!(binder).0);
// FIXME(unsafe_binders) ~^ ERROR use of moved value: `binder.0`
//~^ ERROR use of moved value: `binder.0`
}
}

93
tests/ui/unsafe-binders/moves.stderr
View file

@ -1,37 +1,5 @@
error[E0423]: expected value, found type alias `NotCopy`
--> $DIR/moves.rs:14:20
|
LL | let base = NotCopy;
| ^^^^^^^
|
= note: can't use a type alias as a constructor
error[E0423]: expected value, found type alias `NotCopy`
--> $DIR/moves.rs:23:53
|
LL | let binder: unsafe<> NotCopy = wrap_binder!(NotCopy);
| ^^^^^^^
|
= note: can't use a type alias as a constructor
error[E0423]: expected value, found type alias `NotCopy`
--> $DIR/moves.rs:32:65
|
LL | let binder: unsafe<> (NotCopy, NotCopy) = wrap_binder!((NotCopy, NotCopy));
| ^^^^^^^
|
= note: can't use a type alias as a constructor
error[E0423]: expected value, found type alias `NotCopy`
--> $DIR/moves.rs:32:74
|
LL | let binder: unsafe<> (NotCopy, NotCopy) = wrap_binder!((NotCopy, NotCopy));
| ^^^^^^^
|
= note: can't use a type alias as a constructor
warning: the feature `unsafe_binders` is incomplete and may not be safe to use and/or cause compiler crashes
--> $DIR/moves.rs:3:12
--> $DIR/moves.rs:1:12
|
LL | #![feature(unsafe_binders)]
| ^^^^^^^^^^^^^^
@ -39,47 +7,38 @@ LL | #![feature(unsafe_binders)]
= note: see issue #130516 <https://github.com/rust-lang/rust/issues/130516> for more information
= note: `#[warn(incomplete_features)]` on by default
error[E0277]: the trait bound `NotCopyInner: Copy` is not satisfied
--> $DIR/moves.rs:15:21
error[E0382]: use of moved value: `base`
--> $DIR/moves.rs:15:14
|
LL | let base = NotCopy::default();
| ---- move occurs because `base` has type `ManuallyDrop<NotCopyInner>`, which does not implement the `Copy` trait
LL | let binder: unsafe<> NotCopy = wrap_binder!(base);
| ^^^^^^^^^^^^^^^^ the trait `Copy` is not implemented for `NotCopyInner`
|
= note: required for `ManuallyDrop<NotCopyInner>` to implement `Copy`
help: consider annotating `NotCopyInner` with `#[derive(Copy)]`
|
LL + #[derive(Copy)]
LL | struct NotCopyInner;
|
| ---- value moved here
LL | drop(base);
| ^^^^ value used here after move
error[E0277]: the trait bound `NotCopyInner: Copy` is not satisfied
--> $DIR/moves.rs:23:21
error[E0382]: use of moved value: `binder`
--> $DIR/moves.rs:24:14
|
LL | let binder: unsafe<> NotCopy = wrap_binder!(NotCopy);
| ^^^^^^^^^^^^^^^^ the trait `Copy` is not implemented for `NotCopyInner`
|
= note: required for `ManuallyDrop<NotCopyInner>` to implement `Copy`
help: consider annotating `NotCopyInner` with `#[derive(Copy)]`
|
LL + #[derive(Copy)]
LL | struct NotCopyInner;
LL | drop(unwrap_binder!(binder));
| ---------------------- value moved here
LL | drop(unwrap_binder!(binder));
| ^^^^^^^^^^^^^^^^^^^^^^ value used here after move
|
= note: move occurs because `binder` has type `ManuallyDrop<NotCopyInner>`, which does not implement the `Copy` trait
= note: this error originates in the macro `unwrap_binder` (in Nightly builds, run with -Z macro-backtrace for more info)
error[E0277]: the trait bound `NotCopyInner: Copy` is not satisfied
--> $DIR/moves.rs:32:21
error[E0382]: use of moved value: `binder.0`
--> $DIR/moves.rs:36:14
|
LL | let binder: unsafe<> (NotCopy, NotCopy) = wrap_binder!((NotCopy, NotCopy));
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `Copy` is not implemented for `NotCopyInner`
|
= note: required for `ManuallyDrop<NotCopyInner>` to implement `Copy`
= note: required because it appears within the type `(ManuallyDrop<NotCopyInner>, ManuallyDrop<NotCopyInner>)`
help: consider annotating `NotCopyInner` with `#[derive(Copy)]`
|
LL + #[derive(Copy)]
LL | struct NotCopyInner;
LL | drop(unwrap_binder!(binder).0);
| ------------------------ value moved here
...
LL | drop(unwrap_binder!(binder).0);
| ^^^^^^^^^^^^^^^^^^^^^^^^ value used here after move
|
= note: move occurs because `binder.0` has type `ManuallyDrop<NotCopyInner>`, which does not implement the `Copy` trait
error: aborting due to 7 previous errors; 1 warning emitted
error: aborting due to 3 previous errors; 1 warning emitted
Some errors have detailed explanations: E0277, E0423.
For more information about an error, try `rustc --explain E0277`.
For more information about this error, try `rustc --explain E0382`.