diff options
11 files changed, 120 insertions, 21 deletions
diff --git a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs index 2d9bc45ebc8..e5bc4b38748 100644 --- a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs +++ b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs @@ -1442,9 +1442,14 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, '_, 'infcx, 'tcx> { // See `tests/ui/moves/needs-clone-through-deref.rs` return false; } + // We don't want to suggest `.clone()` in a move closure, since the value has already been captured. if self.in_move_closure(expr) { return false; } + // We also don't want to suggest cloning a closure itself, since the value has already been captured. + if let hir::ExprKind::Closure(_) = expr.kind { + return false; + } // Try to find predicates on *generic params* that would allow copying `ty` let mut suggestion = if let Some(symbol) = tcx.hir().maybe_get_struct_pattern_shorthand_field(expr) { diff --git a/compiler/rustc_mir_transform/src/shim.rs b/compiler/rustc_mir_transform/src/shim.rs index 19e3bf5a599..d2f50040821 100644 --- a/compiler/rustc_mir_transform/src/shim.rs +++ b/compiler/rustc_mir_transform/src/shim.rs @@ -435,6 +435,9 @@ fn build_clone_shim<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId, self_ty: Ty<'tcx>) - match self_ty.kind() { ty::FnDef(..) | ty::FnPtr(_) => builder.copy_shim(), ty::Closure(_, args) => builder.tuple_like_shim(dest, src, args.as_closure().upvar_tys()), + ty::CoroutineClosure(_, args) => { + builder.tuple_like_shim(dest, src, args.as_coroutine_closure().upvar_tys()) + } ty::Tuple(..) => builder.tuple_like_shim(dest, src, self_ty.tuple_fields()), ty::Coroutine(coroutine_def_id, args) => { assert_eq!(tcx.coroutine_movability(*coroutine_def_id), hir::Movability::Movable); diff --git a/compiler/rustc_next_trait_solver/src/solve/assembly/structural_traits.rs b/compiler/rustc_next_trait_solver/src/solve/assembly/structural_traits.rs index 770ac9a929e..60beaa0df84 100644 --- a/compiler/rustc_next_trait_solver/src/solve/assembly/structural_traits.rs +++ b/compiler/rustc_next_trait_solver/src/solve/assembly/structural_traits.rs @@ -217,7 +217,10 @@ where // impl Copy/Clone for Closure where Self::TupledUpvars: Copy/Clone ty::Closure(_, args) => Ok(vec![ty::Binder::dummy(args.as_closure().tupled_upvars_ty())]), - ty::CoroutineClosure(..) => Err(NoSolution), + // impl Copy/Clone for CoroutineClosure where Self::TupledUpvars: Copy/Clone + ty::CoroutineClosure(_, args) => { + Ok(vec![ty::Binder::dummy(args.as_coroutine_closure().tupled_upvars_ty())]) + } // only when `coroutine_clone` is enabled and the coroutine is movable // impl Copy/Clone for Coroutine where T: Copy/Clone forall T in (upvars, witnesses) diff --git a/compiler/rustc_trait_selection/src/traits/select/mod.rs b/compiler/rustc_trait_selection/src/traits/select/mod.rs index c007cd5314a..699c05466bd 100644 --- a/compiler/rustc_trait_selection/src/traits/select/mod.rs +++ b/compiler/rustc_trait_selection/src/traits/select/mod.rs @@ -2262,8 +2262,21 @@ impl<'tcx> SelectionContext<'_, 'tcx> { } } - // FIXME(async_closures): These are never clone, for now. - ty::CoroutineClosure(_, _) => None, + ty::CoroutineClosure(_, args) => { + // (*) binder moved here + let ty = self.infcx.shallow_resolve(args.as_coroutine_closure().tupled_upvars_ty()); + if let ty::Infer(ty::TyVar(_)) = ty.kind() { + // Not yet resolved. + Ambiguous + } else { + Where( + obligation + .predicate + .rebind(args.as_coroutine_closure().upvar_tys().to_vec()), + ) + } + } + // `Copy` and `Clone` are automatically implemented for an anonymous adt // if all of its fields are `Copy` and `Clone` ty::Adt(adt, args) if adt.is_anonymous() => { diff --git a/tests/ui/async-await/async-closures/clone-closure.rs b/tests/ui/async-await/async-closures/clone-closure.rs new file mode 100644 index 00000000000..807897e3e03 --- /dev/null +++ b/tests/ui/async-await/async-closures/clone-closure.rs @@ -0,0 +1,24 @@ +//@ aux-build:block-on.rs +//@ edition:2021 +//@ run-pass +//@ check-run-results + +#![feature(async_closure)] + +extern crate block_on; + +async fn for_each(f: impl async FnOnce(&str) + Clone) { + f.clone()("world").await; + f.clone()("world2").await; +} + +fn main() { + block_on::block_on(async_main()); +} + +async fn async_main() { + let x = String::from("Hello,"); + for_each(async move |s| { + println!("{x} {s}"); + }).await; +} diff --git a/tests/ui/async-await/async-closures/clone-closure.run.stdout b/tests/ui/async-await/async-closures/clone-closure.run.stdout new file mode 100644 index 00000000000..0cfcf1923da --- /dev/null +++ b/tests/ui/async-await/async-closures/clone-closure.run.stdout @@ -0,0 +1,2 @@ +Hello, world +Hello, world2 diff --git a/tests/ui/async-await/async-closures/move-consuming-capture.stderr b/tests/ui/async-await/async-closures/move-consuming-capture.stderr index 45c1eac8f8f..4ce71ec49d6 100644 --- a/tests/ui/async-await/async-closures/move-consuming-capture.stderr +++ b/tests/ui/async-await/async-closures/move-consuming-capture.stderr @@ -11,6 +11,15 @@ LL | x().await; | note: `async_call_once` takes ownership of the receiver `self`, which moves `x` --> $SRC_DIR/core/src/ops/async_function.rs:LL:COL +help: you could `clone` the value and consume it, if the `NoCopy: Clone` trait bound could be satisfied + | +LL | x.clone()().await; + | ++++++++ +help: consider annotating `NoCopy` with `#[derive(Clone)]` + | +LL + #[derive(Clone)] +LL | struct NoCopy; + | error: aborting due to 1 previous error diff --git a/tests/ui/async-await/async-closures/not-clone-closure.rs b/tests/ui/async-await/async-closures/not-clone-closure.rs new file mode 100644 index 00000000000..2776ce4690f --- /dev/null +++ b/tests/ui/async-await/async-closures/not-clone-closure.rs @@ -0,0 +1,36 @@ +//@ edition: 2021 + +#![feature(async_closure)] + +struct NotClonableArg; +#[derive(Default)] +struct NotClonableReturnType; + +// Verify that the only components that we care about are the upvars, not the signature. +fn we_are_okay_with_not_clonable_signature() { + let x = async |x: NotClonableArg| -> NotClonableReturnType { Default::default() }; + x.clone(); // Okay +} + +#[derive(Debug)] +struct NotClonableUpvar; + +fn we_only_care_about_clonable_upvars() { + let x = NotClonableUpvar; + // Notably, this is clone because we capture `&x`. + let yes_clone = async || { + println!("{x:?}"); + }; + yes_clone.clone(); // Okay + + let z = NotClonableUpvar; + // However, this is not because the closure captures `z` by move. + // (Even though the future that is lent out captures `z by ref!) + let not_clone = async move || { + println!("{z:?}"); + }; + not_clone.clone(); + //~^ ERROR the trait bound `NotClonableUpvar: Clone` is not satisfied +} + +fn main() {} diff --git a/tests/ui/async-await/async-closures/not-clone-closure.stderr b/tests/ui/async-await/async-closures/not-clone-closure.stderr new file mode 100644 index 00000000000..aea48a455c2 --- /dev/null +++ b/tests/ui/async-await/async-closures/not-clone-closure.stderr @@ -0,0 +1,20 @@ +error[E0277]: the trait bound `NotClonableUpvar: Clone` is not satisfied in `{async closure@$DIR/not-clone-closure.rs:29:21: 29:34}` + --> $DIR/not-clone-closure.rs:32:15 + | +LL | not_clone.clone(); + | ^^^^^ within `{async closure@$DIR/not-clone-closure.rs:29:21: 29:34}`, the trait `Clone` is not implemented for `NotClonableUpvar`, which is required by `{async closure@$DIR/not-clone-closure.rs:29:21: 29:34}: Clone` + | +note: required because it's used within this closure + --> $DIR/not-clone-closure.rs:29:21 + | +LL | let not_clone = async move || { + | ^^^^^^^^^^^^^ +help: consider annotating `NotClonableUpvar` with `#[derive(Clone)]` + | +LL + #[derive(Clone)] +LL | struct NotClonableUpvar; + | + +error: aborting due to 1 previous error + +For more information about this error, try `rustc --explain E0277`. diff --git a/tests/ui/async-await/async-closures/without-precise-captures-we-are-powerless.rs b/tests/ui/async-await/async-closures/without-precise-captures-we-are-powerless.rs index 17681161e20..18f16ca4b2d 100644 --- a/tests/ui/async-await/async-closures/without-precise-captures-we-are-powerless.rs +++ b/tests/ui/async-await/async-closures/without-precise-captures-we-are-powerless.rs @@ -19,7 +19,7 @@ fn simple<'a>(x: &'a i32) { let c = async move || { println!("{}", *x); }; outlives::<'a>(c()); //~ ERROR `c` does not live long enough - outlives::<'a>(call_once(c)); //~ ERROR cannot move out of `c` + outlives::<'a>(call_once(c)); } struct S<'a>(&'a i32); diff --git a/tests/ui/async-await/async-closures/without-precise-captures-we-are-powerless.stderr b/tests/ui/async-await/async-closures/without-precise-captures-we-are-powerless.stderr index 569028934cb..1df5abdbb18 100644 --- a/tests/ui/async-await/async-closures/without-precise-captures-we-are-powerless.stderr +++ b/tests/ui/async-await/async-closures/without-precise-captures-we-are-powerless.stderr @@ -29,22 +29,6 @@ LL | outlives::<'a>(call_once(c)); LL | } | - `c` dropped here while still borrowed -error[E0505]: cannot move out of `c` because it is borrowed - --> $DIR/without-precise-captures-we-are-powerless.rs:22:30 - | -LL | fn simple<'a>(x: &'a i32) { - | -- lifetime `'a` defined here -... -LL | let c = async move || { println!("{}", *x); }; - | - binding `c` declared here -LL | outlives::<'a>(c()); - | --- - | | - | borrow of `c` occurs here - | argument requires that `c` is borrowed for `'a` -LL | outlives::<'a>(call_once(c)); - | ^ move out of `c` occurs here - error[E0597]: `x` does not live long enough --> $DIR/without-precise-captures-we-are-powerless.rs:28:13 | @@ -146,7 +130,7 @@ LL | // outlives::<'a>(call_once(c)); // FIXME(async_closures): Figure out w LL | } | - `c` dropped here while still borrowed -error: aborting due to 10 previous errors +error: aborting due to 9 previous errors Some errors have detailed explanations: E0505, E0597, E0621. For more information about an error, try `rustc --explain E0505`. |