diff options
| -rw-r--r-- | compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs | 1 | ||||
| -rw-r--r-- | compiler/rustc_trait_selection/src/traits/wf.rs | 11 | ||||
| -rw-r--r-- | tests/ui/for/issue-20605.next.stderr | 2 | ||||
| -rw-r--r-- | tests/ui/for/issue-20605.rs | 2 | ||||
| -rw-r--r-- | tests/ui/traits/new-solver/alias-bound-unsound.rs | 2 | ||||
| -rw-r--r-- | tests/ui/traits/new-solver/alias-bound-unsound.stderr | 14 |
6 files changed, 27 insertions, 5 deletions
diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs index 67745f04641..557341f7ac8 100644 --- a/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs +++ b/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs @@ -1049,6 +1049,7 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> { } ty::PredicateKind::Clause(ty::ClauseKind::WellFormed(ty)) => { + let ty = self.resolve_vars_if_possible(ty); match self.tcx.sess.opts.unstable_opts.trait_solver { TraitSolver::Classic => { // WF predicates cannot themselves make diff --git a/compiler/rustc_trait_selection/src/traits/wf.rs b/compiler/rustc_trait_selection/src/traits/wf.rs index e80d413d976..e96e89ce73c 100644 --- a/compiler/rustc_trait_selection/src/traits/wf.rs +++ b/compiler/rustc_trait_selection/src/traits/wf.rs @@ -77,12 +77,19 @@ pub fn unnormalized_obligations<'tcx>( param_env: ty::ParamEnv<'tcx>, arg: GenericArg<'tcx>, ) -> Option<Vec<traits::PredicateObligation<'tcx>>> { + debug_assert_eq!(arg, infcx.resolve_vars_if_possible(arg)); + + // However, if `arg` IS an unresolved inference variable, returns `None`, + // because we are not able to make any progress at all. This is to prevent + // "livelock" where we say "$0 is WF if $0 is WF". + if arg.is_non_region_infer() { + return None; + } + if let ty::GenericArgKind::Lifetime(..) = arg.unpack() { return Some(vec![]); } - debug_assert_eq!(arg, infcx.resolve_vars_if_possible(arg)); - let mut wf = WfPredicates { infcx, param_env, diff --git a/tests/ui/for/issue-20605.next.stderr b/tests/ui/for/issue-20605.next.stderr index 5362a68c834..a96a53ca93e 100644 --- a/tests/ui/for/issue-20605.next.stderr +++ b/tests/ui/for/issue-20605.next.stderr @@ -14,7 +14,7 @@ LL | for item in *things { *item = 0 } = note: all local variables must have a statically known size = help: unsized locals are gated as an unstable feature -error: the type `<_ as IntoIterator>::IntoIter` is not well-formed +error: the type `<dyn Iterator<Item = &'a mut u8> as IntoIterator>::IntoIter` is not well-formed --> $DIR/issue-20605.rs:5:17 | LL | for item in *things { *item = 0 } diff --git a/tests/ui/for/issue-20605.rs b/tests/ui/for/issue-20605.rs index 499271fa92f..64156b35705 100644 --- a/tests/ui/for/issue-20605.rs +++ b/tests/ui/for/issue-20605.rs @@ -4,7 +4,7 @@ fn changer<'a>(mut things: Box<dyn Iterator<Item=&'a mut u8>>) { for item in *things { *item = 0 } //~^ ERROR the size for values of type - //[next]~^^ ERROR the type `<_ as IntoIterator>::IntoIter` is not well-formed + //[next]~^^ ERROR the type `<dyn Iterator<Item = &'a mut u8> as IntoIterator>::IntoIter` is not well-formed //[next]~| ERROR the trait bound `dyn Iterator<Item = &'a mut u8>: IntoIterator` is not satisfied } diff --git a/tests/ui/traits/new-solver/alias-bound-unsound.rs b/tests/ui/traits/new-solver/alias-bound-unsound.rs index 00294c708f1..6b6a77e2c7e 100644 --- a/tests/ui/traits/new-solver/alias-bound-unsound.rs +++ b/tests/ui/traits/new-solver/alias-bound-unsound.rs @@ -23,5 +23,7 @@ fn main() { drop(<() as Foo>::copy_me(&x)); //~^ ERROR `<() as Foo>::Item: Copy` is not satisfied //~| ERROR `<() as Foo>::Item` is not well-formed + //~| ERROR `<() as Foo>::Item` is not well-formed + //~| ERROR `<() as Foo>::Item` is not well-formed println!("{x}"); } diff --git a/tests/ui/traits/new-solver/alias-bound-unsound.stderr b/tests/ui/traits/new-solver/alias-bound-unsound.stderr index 9a43d2a6639..89abc608213 100644 --- a/tests/ui/traits/new-solver/alias-bound-unsound.stderr +++ b/tests/ui/traits/new-solver/alias-bound-unsound.stderr @@ -19,6 +19,18 @@ error: the type `<() as Foo>::Item` is not well-formed LL | drop(<() as Foo>::copy_me(&x)); | ^^^^^^^^^^^^^^^^^^^^^^^^ -error: aborting due to 2 previous errors +error: the type `<() as Foo>::Item` is not well-formed + --> $DIR/alias-bound-unsound.rs:23:5 + | +LL | drop(<() as Foo>::copy_me(&x)); + | ^^^^ + +error: the type `<() as Foo>::Item` is not well-formed + --> $DIR/alias-bound-unsound.rs:23:10 + | +LL | drop(<() as Foo>::copy_me(&x)); + | ^^^^^^^^^^^^^^^^^^^^^^^^ + +error: aborting due to 4 previous errors For more information about this error, try `rustc --explain E0277`. |