From 56c135c9253563f92755b0a9cd54ec67f7c17fc7 Mon Sep 17 00:00:00 2001 From: Oli Scherer Date: Fri, 24 May 2024 13:21:59 +0000 Subject: [PATCH 1/2] Revert "Rollup merge of #123979 - oli-obk:define_opaque_types7, r=compiler-errors" This reverts commit f939d1ff4820844595d0f50f94038869f1445d08, reversing changes made to 183c706305d8c4e0ccb0967932381baf7e0c3611. --- compiler/rustc_infer/src/infer/mod.rs | 17 ++--------------- 1 file changed, 2 insertions(+), 15 deletions(-) diff --git a/compiler/rustc_infer/src/infer/mod.rs b/compiler/rustc_infer/src/infer/mod.rs index 8d4011421bd..6f603d9b612 100644 --- a/compiler/rustc_infer/src/infer/mod.rs +++ b/compiler/rustc_infer/src/infer/mod.rs @@ -957,27 +957,14 @@ pub fn subtype_predicate( (&ty::Infer(ty::TyVar(a_vid)), &ty::Infer(ty::TyVar(b_vid))) => { return Err((a_vid, b_vid)); } - // We don't silently want to constrain hidden types here, so we assert that either one side is - // an infer var, so it'll get constrained to whatever the other side is, or there are no opaque - // types involved. - // We don't expect this to actually get hit, but if it does, we now at least know how to write - // a test for it. - (_, ty::Infer(ty::TyVar(_))) => {} - (ty::Infer(ty::TyVar(_)), _) => {} - _ if r_a != r_b && (r_a, r_b).has_opaque_types() => { - span_bug!( - cause.span(), - "opaque types got hidden types registered from within subtype predicate: {r_a:?} vs {r_b:?}" - ) - } _ => {} } self.enter_forall(predicate, |ty::SubtypePredicate { a_is_expected, a, b }| { if a_is_expected { - Ok(self.at(cause, param_env).sub(DefineOpaqueTypes::Yes, a, b)) + Ok(self.at(cause, param_env).sub(DefineOpaqueTypes::No, a, b)) } else { - Ok(self.at(cause, param_env).sup(DefineOpaqueTypes::Yes, b, a)) + Ok(self.at(cause, param_env).sup(DefineOpaqueTypes::No, b, a)) } }) } From 526090b901cbedcef7e1eec132e217917606a54d Mon Sep 17 00:00:00 2001 From: Oli Scherer Date: Thu, 23 May 2024 10:03:55 +0000 Subject: [PATCH 2/2] Add regression tests --- tests/crashes/124891.rs | 22 ------- .../impl-trait/lazy_subtyping_of_opaques.rs | 59 +++++++++++++++++++ .../lazy_subtyping_of_opaques.stderr | 21 +++++++ .../lazy_subtyping_of_opaques.rs | 30 ++++++++++ .../lazy_subtyping_of_opaques.stderr | 26 ++++++++ 5 files changed, 136 insertions(+), 22 deletions(-) delete mode 100644 tests/crashes/124891.rs create mode 100644 tests/ui/impl-trait/lazy_subtyping_of_opaques.rs create mode 100644 tests/ui/impl-trait/lazy_subtyping_of_opaques.stderr create mode 100644 tests/ui/type-alias-impl-trait/lazy_subtyping_of_opaques.rs create mode 100644 tests/ui/type-alias-impl-trait/lazy_subtyping_of_opaques.stderr diff --git a/tests/crashes/124891.rs b/tests/crashes/124891.rs deleted file mode 100644 index 9b5892418c8..00000000000 --- a/tests/crashes/124891.rs +++ /dev/null @@ -1,22 +0,0 @@ -//@ known-bug: rust-lang/rust#124891 - -type Tait = impl FnOnce() -> (); - -fn reify_as_tait() -> Thunk { - Thunk::new(|cont| cont) -} - -struct Thunk(F); - -impl Thunk { - fn new(f: F) - where - F: ContFn, - { - todo!(); - } -} - -trait ContFn {} - -impl ()> ContFn for F {} diff --git a/tests/ui/impl-trait/lazy_subtyping_of_opaques.rs b/tests/ui/impl-trait/lazy_subtyping_of_opaques.rs new file mode 100644 index 00000000000..65331894725 --- /dev/null +++ b/tests/ui/impl-trait/lazy_subtyping_of_opaques.rs @@ -0,0 +1,59 @@ +//! This test checks that we allow subtyping predicates that contain opaque types. +//! No hidden types are being constrained in the subtyping predicate, but type and +//! lifetime variables get subtyped in the generic parameter list of the opaque. + +use std::iter; + +mod either { + pub enum Either { + Left(L), + Right(R), + } + + impl> Iterator for Either { + type Item = L::Item; + fn next(&mut self) -> Option { + todo!() + } + } + pub use self::Either::{Left, Right}; +} + +pub enum BabeConsensusLogRef<'a> { + NextEpochData(BabeNextEpochRef<'a>), + NextConfigData, +} + +impl<'a> BabeConsensusLogRef<'a> { + pub fn scale_encoding( + &self, + ) -> impl Iterator + Clone + 'a> + Clone + 'a { + //~^ ERROR is not satisfied + //~| ERROR is not satisfied + //~| ERROR is not satisfied + match self { + BabeConsensusLogRef::NextEpochData(digest) => either::Left(either::Left( + digest.scale_encoding().map(either::Left).map(either::Left), + )), + BabeConsensusLogRef::NextConfigData => either::Right( + // The Opaque type from ``scale_encoding` gets used opaquely here, while the `R` + // generic parameter of `Either` contains type variables that get subtyped and the + // opaque type contains lifetime variables that get subtyped. + iter::once(either::Right(either::Left([1]))) + .chain(std::iter::once([1]).map(either::Right).map(either::Right)), + ), + } + } +} + +pub struct BabeNextEpochRef<'a>(&'a ()); + +impl<'a> BabeNextEpochRef<'a> { + pub fn scale_encoding( + &self, + ) -> impl Iterator + Clone + 'a> + Clone + 'a { + std::iter::once([1]) + } +} + +fn main() {} diff --git a/tests/ui/impl-trait/lazy_subtyping_of_opaques.stderr b/tests/ui/impl-trait/lazy_subtyping_of_opaques.stderr new file mode 100644 index 00000000000..2f8c957c2c7 --- /dev/null +++ b/tests/ui/impl-trait/lazy_subtyping_of_opaques.stderr @@ -0,0 +1,21 @@ +error[E0277]: the trait bound `Either + Clone + '_> + Clone + '_, fn(impl AsRef<[u8]> + Clone + '_) -> Either + Clone + '_, _> {Either:: + Clone + '_, _>::Left}>, fn(Either + Clone + '_, _>) -> Either + Clone + '_, _>, Either<[{integer}; 1], [{integer}; 1]>> {Either:: + Clone + '_, _>, Either<[{integer}; 1], [{integer}; 1]>>::Left}>, _>, std::iter::Chain + Clone + '_, _>, Either<[{integer}; 1], [{integer}; 1]>>>, Map, fn([{integer}; 1]) -> Either<[{integer}; 1], [{integer}; 1]> {Either::<[{integer}; 1], [{integer}; 1]>::Right}>, fn(Either<[{integer}; 1], [{integer}; 1]>) -> Either + Clone + '_, _>, Either<[{integer}; 1], [{integer}; 1]>> {Either:: + Clone + '_, _>, Either<[{integer}; 1], [{integer}; 1]>>::Right}>>>: Clone` is not satisfied + --> $DIR/lazy_subtyping_of_opaques.rs:30:10 + | +LL | ) -> impl Iterator + Clone + 'a> + Clone + 'a { + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `Clone` is not implemented for `Either + Clone + '_> + Clone + '_, fn(impl AsRef<[u8]> + Clone + '_) -> Either + Clone + '_, _> {Either:: + Clone + '_, _>::Left}>, fn(Either + Clone + '_, _>) -> Either + Clone + '_, _>, Either<[{integer}; 1], [{integer}; 1]>> {Either:: + Clone + '_, _>, Either<[{integer}; 1], [{integer}; 1]>>::Left}>, _>, std::iter::Chain + Clone + '_, _>, Either<[{integer}; 1], [{integer}; 1]>>>, Map, fn([{integer}; 1]) -> Either<[{integer}; 1], [{integer}; 1]> {Either::<[{integer}; 1], [{integer}; 1]>::Right}>, fn(Either<[{integer}; 1], [{integer}; 1]>) -> Either + Clone + '_, _>, Either<[{integer}; 1], [{integer}; 1]>> {Either:: + Clone + '_, _>, Either<[{integer}; 1], [{integer}; 1]>>::Right}>>>` + +error[E0277]: the trait bound `Either + Clone + '_, _>, Either<[{integer}; 1], [{integer}; 1]>>: AsRef<[u8]>` is not satisfied + --> $DIR/lazy_subtyping_of_opaques.rs:30:31 + | +LL | ) -> impl Iterator + Clone + 'a> + Clone + 'a { + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `AsRef<[u8]>` is not implemented for `Either + Clone + '_, _>, Either<[{integer}; 1], [{integer}; 1]>>` + +error[E0277]: the trait bound `Either + Clone + '_, _>, Either<[{integer}; 1], [{integer}; 1]>>: Clone` is not satisfied + --> $DIR/lazy_subtyping_of_opaques.rs:30:31 + | +LL | ) -> impl Iterator + Clone + 'a> + Clone + 'a { + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `Clone` is not implemented for `Either + Clone + '_, _>, Either<[{integer}; 1], [{integer}; 1]>>` + +error: aborting due to 3 previous errors + +For more information about this error, try `rustc --explain E0277`. diff --git a/tests/ui/type-alias-impl-trait/lazy_subtyping_of_opaques.rs b/tests/ui/type-alias-impl-trait/lazy_subtyping_of_opaques.rs new file mode 100644 index 00000000000..72a90287e37 --- /dev/null +++ b/tests/ui/type-alias-impl-trait/lazy_subtyping_of_opaques.rs @@ -0,0 +1,30 @@ +#![feature(type_alias_impl_trait)] + +//! This test used to ICE rust-lang/rust#124891 +//! because we added an assertion for catching cases where opaque types get +//! registered during the processing of subtyping predicates. + +type Tait = impl FnOnce() -> (); + +fn reify_as_tait() -> Thunk { + Thunk::new(|cont| cont) + //~^ ERROR: mismatched types + //~| ERROR: mismatched types +} + +struct Thunk(F); + +impl Thunk { + fn new(f: F) + where + F: ContFn, + { + todo!(); + } +} + +trait ContFn {} + +impl ()> ContFn for F {} + +fn main() {} diff --git a/tests/ui/type-alias-impl-trait/lazy_subtyping_of_opaques.stderr b/tests/ui/type-alias-impl-trait/lazy_subtyping_of_opaques.stderr new file mode 100644 index 00000000000..5a35dc27446 --- /dev/null +++ b/tests/ui/type-alias-impl-trait/lazy_subtyping_of_opaques.stderr @@ -0,0 +1,26 @@ +error[E0308]: mismatched types + --> $DIR/lazy_subtyping_of_opaques.rs:10:23 + | +LL | type Tait = impl FnOnce() -> (); + | ------------------- the found opaque type +... +LL | Thunk::new(|cont| cont) + | ^^^^ expected `()`, found opaque type + | + = note: expected unit type `()` + found opaque type `Tait` + +error[E0308]: mismatched types + --> $DIR/lazy_subtyping_of_opaques.rs:10:5 + | +LL | fn reify_as_tait() -> Thunk { + | ----------- expected `Thunk<_>` because of return type +LL | Thunk::new(|cont| cont) + | ^^^^^^^^^^^^^^^^^^^^^^^ expected `Thunk<_>`, found `()` + | + = note: expected struct `Thunk<_>` + found unit type `()` + +error: aborting due to 2 previous errors + +For more information about this error, try `rustc --explain E0308`.