diff --git a/compiler/rustc_hir_analysis/src/check/dropck.rs b/compiler/rustc_hir_analysis/src/check/dropck.rs index e5b212eb757b..3d55ffc595f5 100644 --- a/compiler/rustc_hir_analysis/src/check/dropck.rs +++ b/compiler/rustc_hir_analysis/src/check/dropck.rs @@ -184,13 +184,7 @@ fn ensure_drop_predicates_are_implied_by_item_defn<'tcx>( let p = p.kind(); match (predicate.skip_binder(), p.skip_binder()) { (ty::PredicateKind::Trait(a), ty::PredicateKind::Trait(b)) => { - // Since struct predicates cannot have ~const, project the impl predicate - // onto one that ignores the constness. This is equivalent to saying that - // we match a `Trait` bound on the struct with a `Trait` or `~const Trait` - // in the impl. - let non_const_a = - ty::TraitPredicate { constness: ty::BoundConstness::NotConst, ..a }; - relator.relate(predicate.rebind(non_const_a), p.rebind(b)).is_ok() + relator.relate(predicate.rebind(a), p.rebind(b)).is_ok() } (ty::PredicateKind::Projection(a), ty::PredicateKind::Projection(b)) => { relator.relate(predicate.rebind(a), p.rebind(b)).is_ok() diff --git a/src/test/ui/rfc-2632-const-trait-impl/const-drop-fail.precise.stderr b/src/test/ui/rfc-2632-const-trait-impl/const-drop-fail.precise.stderr index ddf0e2d91c09..796c0d388eaf 100644 --- a/src/test/ui/rfc-2632-const-trait-impl/const-drop-fail.precise.stderr +++ b/src/test/ui/rfc-2632-const-trait-impl/const-drop-fail.precise.stderr @@ -45,34 +45,55 @@ note: required by a bound in `check` LL | const fn check(_: T) {} | ^^^^^^^^^^^^^^^ required by this bound in `check` -error[E0277]: the trait bound `ConstDropImplWithBounds: ~const Destruct` is not satisfied +error[E0277]: the trait bound `NonTrivialDrop: ~const A` is not satisfied + --> $DIR/const-drop-fail.rs:48:47 + | +LL | ConstDropImplWithBounds::(PhantomData), + | ----------------------------------------- ^^^^^^^^^^^ the trait `~const A` is not implemented for `NonTrivialDrop` + | | + | required by a bound introduced by this call + | +note: the trait `A` is implemented for `NonTrivialDrop`, but that implementation is not `const` + --> $DIR/const-drop-fail.rs:48:47 + | +LL | ConstDropImplWithBounds::(PhantomData), + | ^^^^^^^^^^^ +note: required by a bound in `ConstDropImplWithBounds` + --> $DIR/const-drop-fail.rs:27:35 + | +LL | struct ConstDropImplWithBounds(PhantomData); + | ^^^^^^^^ required by this bound in `ConstDropImplWithBounds` + +error[E0277]: the trait bound `NonTrivialDrop: ~const A` is not satisfied --> $DIR/const-drop-fail.rs:48:5 | -LL | const _: () = check($exp); - | ----- required by a bound introduced by this call -... LL | ConstDropImplWithBounds::(PhantomData), - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `~const Destruct` is not implemented for `ConstDropImplWithBounds` + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `~const A` is not implemented for `NonTrivialDrop` | -note: required for `ConstDropImplWithBounds` to implement `~const Destruct` - --> $DIR/const-drop-fail.rs:29:25 +note: the trait `A` is implemented for `NonTrivialDrop`, but that implementation is not `const` + --> $DIR/const-drop-fail.rs:48:5 | -LL | impl const Drop for ConstDropImplWithBounds { - | ^^^^ ^^^^^^^^^^^^^^^^^^^^^^^^^^ - = note: 1 redundant requirement hidden - = note: required for `ConstDropImplWithBounds` to implement `~const Destruct` -note: required by a bound in `check` - --> $DIR/const-drop-fail.rs:35:19 +LL | ConstDropImplWithBounds::(PhantomData), + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ +note: required by a bound in `ConstDropImplWithBounds` + --> $DIR/const-drop-fail.rs:27:35 | -LL | const fn check(_: T) {} - | ^^^^^^^^^^^^^^^ required by this bound in `check` -help: consider borrowing here - | -LL | &ConstDropImplWithBounds::(PhantomData), - | + -LL | &mut ConstDropImplWithBounds::(PhantomData), - | ++++ +LL | struct ConstDropImplWithBounds(PhantomData); + | ^^^^^^^^ required by this bound in `ConstDropImplWithBounds` -error: aborting due to 3 previous errors +error[E0367]: `Drop` impl requires `T: ~const A` but the struct it is implemented for does not + --> $DIR/const-drop-fail.rs:55:9 + | +LL | impl const Drop for ConstDropImplWithNonConstBounds { + | ^^^^^^^^ + | +note: the implementor must specify the same requirement + --> $DIR/const-drop-fail.rs:53:1 + | +LL | struct ConstDropImplWithNonConstBounds(PhantomData); + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ -For more information about this error, try `rustc --explain E0277`. +error: aborting due to 5 previous errors + +Some errors have detailed explanations: E0277, E0367. +For more information about an error, try `rustc --explain E0277`. diff --git a/src/test/ui/rfc-2632-const-trait-impl/const-drop-fail.rs b/src/test/ui/rfc-2632-const-trait-impl/const-drop-fail.rs index 565e2c77ac5c..d36c7f81ced8 100644 --- a/src/test/ui/rfc-2632-const-trait-impl/const-drop-fail.rs +++ b/src/test/ui/rfc-2632-const-trait-impl/const-drop-fail.rs @@ -24,7 +24,7 @@ trait A { fn a() { } } impl A for NonTrivialDrop {} -struct ConstDropImplWithBounds(PhantomData); +struct ConstDropImplWithBounds(PhantomData); impl const Drop for ConstDropImplWithBounds { fn drop(&mut self) { @@ -47,6 +47,16 @@ check_all! { //~^ ERROR can't drop ConstDropImplWithBounds::(PhantomData), //~^ ERROR the trait bound + //~| ERROR the trait bound +} + +struct ConstDropImplWithNonConstBounds(PhantomData); + +impl const Drop for ConstDropImplWithNonConstBounds { +//~^ ERROR `Drop` impl requires `T: ~const A` but the struct it is implemented for does not + fn drop(&mut self) { + T::a(); + } } fn main() {} diff --git a/src/test/ui/rfc-2632-const-trait-impl/const-drop-fail.stock.stderr b/src/test/ui/rfc-2632-const-trait-impl/const-drop-fail.stock.stderr index ddf0e2d91c09..796c0d388eaf 100644 --- a/src/test/ui/rfc-2632-const-trait-impl/const-drop-fail.stock.stderr +++ b/src/test/ui/rfc-2632-const-trait-impl/const-drop-fail.stock.stderr @@ -45,34 +45,55 @@ note: required by a bound in `check` LL | const fn check(_: T) {} | ^^^^^^^^^^^^^^^ required by this bound in `check` -error[E0277]: the trait bound `ConstDropImplWithBounds: ~const Destruct` is not satisfied +error[E0277]: the trait bound `NonTrivialDrop: ~const A` is not satisfied + --> $DIR/const-drop-fail.rs:48:47 + | +LL | ConstDropImplWithBounds::(PhantomData), + | ----------------------------------------- ^^^^^^^^^^^ the trait `~const A` is not implemented for `NonTrivialDrop` + | | + | required by a bound introduced by this call + | +note: the trait `A` is implemented for `NonTrivialDrop`, but that implementation is not `const` + --> $DIR/const-drop-fail.rs:48:47 + | +LL | ConstDropImplWithBounds::(PhantomData), + | ^^^^^^^^^^^ +note: required by a bound in `ConstDropImplWithBounds` + --> $DIR/const-drop-fail.rs:27:35 + | +LL | struct ConstDropImplWithBounds(PhantomData); + | ^^^^^^^^ required by this bound in `ConstDropImplWithBounds` + +error[E0277]: the trait bound `NonTrivialDrop: ~const A` is not satisfied --> $DIR/const-drop-fail.rs:48:5 | -LL | const _: () = check($exp); - | ----- required by a bound introduced by this call -... LL | ConstDropImplWithBounds::(PhantomData), - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `~const Destruct` is not implemented for `ConstDropImplWithBounds` + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `~const A` is not implemented for `NonTrivialDrop` | -note: required for `ConstDropImplWithBounds` to implement `~const Destruct` - --> $DIR/const-drop-fail.rs:29:25 +note: the trait `A` is implemented for `NonTrivialDrop`, but that implementation is not `const` + --> $DIR/const-drop-fail.rs:48:5 | -LL | impl const Drop for ConstDropImplWithBounds { - | ^^^^ ^^^^^^^^^^^^^^^^^^^^^^^^^^ - = note: 1 redundant requirement hidden - = note: required for `ConstDropImplWithBounds` to implement `~const Destruct` -note: required by a bound in `check` - --> $DIR/const-drop-fail.rs:35:19 +LL | ConstDropImplWithBounds::(PhantomData), + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ +note: required by a bound in `ConstDropImplWithBounds` + --> $DIR/const-drop-fail.rs:27:35 | -LL | const fn check(_: T) {} - | ^^^^^^^^^^^^^^^ required by this bound in `check` -help: consider borrowing here - | -LL | &ConstDropImplWithBounds::(PhantomData), - | + -LL | &mut ConstDropImplWithBounds::(PhantomData), - | ++++ +LL | struct ConstDropImplWithBounds(PhantomData); + | ^^^^^^^^ required by this bound in `ConstDropImplWithBounds` -error: aborting due to 3 previous errors +error[E0367]: `Drop` impl requires `T: ~const A` but the struct it is implemented for does not + --> $DIR/const-drop-fail.rs:55:9 + | +LL | impl const Drop for ConstDropImplWithNonConstBounds { + | ^^^^^^^^ + | +note: the implementor must specify the same requirement + --> $DIR/const-drop-fail.rs:53:1 + | +LL | struct ConstDropImplWithNonConstBounds(PhantomData); + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ -For more information about this error, try `rustc --explain E0277`. +error: aborting due to 5 previous errors + +Some errors have detailed explanations: E0277, E0367. +For more information about an error, try `rustc --explain E0277`. diff --git a/src/test/ui/rfc-2632-const-trait-impl/const-drop.rs b/src/test/ui/rfc-2632-const-trait-impl/const-drop.rs index 8b4c40658156..b0fc3adf984a 100644 --- a/src/test/ui/rfc-2632-const-trait-impl/const-drop.rs +++ b/src/test/ui/rfc-2632-const-trait-impl/const-drop.rs @@ -60,7 +60,7 @@ mod t { fn foo() {} } - pub struct ConstDropWithBound(pub core::marker::PhantomData); + pub struct ConstDropWithBound(pub core::marker::PhantomData); impl const Drop for ConstDropWithBound { fn drop(&mut self) { diff --git a/src/test/ui/rfc-2632-const-trait-impl/tilde_const_on_impl_bound.rs b/src/test/ui/rfc-2632-const-trait-impl/tilde_const_on_impl_bound.rs new file mode 100644 index 000000000000..285cef571f33 --- /dev/null +++ b/src/test/ui/rfc-2632-const-trait-impl/tilde_const_on_impl_bound.rs @@ -0,0 +1,17 @@ +// check-pass +#![feature(const_trait_impl)] + +#[const_trait] +trait Foo { + fn foo(&self) {} +} + +struct Bar(T); + +impl Bar { + const fn foo(&self) { + self.0.foo() + } +} + +fn main() {}