diff --git a/compiler/rustc_trait_selection/src/traits/select/mod.rs b/compiler/rustc_trait_selection/src/traits/select/mod.rs index 515f3a34988..8835f2cc1b9 100644 --- a/compiler/rustc_trait_selection/src/traits/select/mod.rs +++ b/compiler/rustc_trait_selection/src/traits/select/mod.rs @@ -371,23 +371,28 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { if !candidate_set.ambiguous && no_candidates_apply { let trait_ref = stack.obligation.predicate.skip_binder().trait_ref; - let self_ty = trait_ref.self_ty(); - let (trait_desc, self_desc) = with_no_trimmed_paths!({ - let trait_desc = trait_ref.print_only_trait_path().to_string(); - let self_desc = if self_ty.has_concrete_skeleton() { - Some(self_ty.to_string()) + if !trait_ref.references_error() { + let self_ty = trait_ref.self_ty(); + let (trait_desc, self_desc) = with_no_trimmed_paths!({ + let trait_desc = trait_ref.print_only_trait_path().to_string(); + let self_desc = if self_ty.has_concrete_skeleton() { + Some(self_ty.to_string()) + } else { + None + }; + (trait_desc, self_desc) + }); + let cause = if let Conflict::Upstream = conflict { + IntercrateAmbiguityCause::UpstreamCrateUpdate { + trait_desc, + self_desc, + } } else { - None + IntercrateAmbiguityCause::DownstreamCrate { trait_desc, self_desc } }; - (trait_desc, self_desc) - }); - let cause = if let Conflict::Upstream = conflict { - IntercrateAmbiguityCause::UpstreamCrateUpdate { trait_desc, self_desc } - } else { - IntercrateAmbiguityCause::DownstreamCrate { trait_desc, self_desc } - }; - debug!(?cause, "evaluate_stack: pushing cause"); - self.intercrate_ambiguity_causes.as_mut().unwrap().insert(cause); + debug!(?cause, "evaluate_stack: pushing cause"); + self.intercrate_ambiguity_causes.as_mut().unwrap().insert(cause); + } } } } diff --git a/src/test/ui/trait-bounds/impl-bound-with-references-error.rs b/src/test/ui/trait-bounds/impl-bound-with-references-error.rs new file mode 100644 index 00000000000..e5d0a1aaed0 --- /dev/null +++ b/src/test/ui/trait-bounds/impl-bound-with-references-error.rs @@ -0,0 +1,20 @@ +// Regression test for #105138. +// This test ensures that the compiler does not add note +// for implementation of trait whose inner type is erroneous. + +pub enum LabelText { + Plain, +} + +impl From for LabelText +//~^ ERROR conflicting implementations of trait `From` for type `LabelText` [E0119] +where + T: Into>, + //~^ ERROR cannot find type `Cow` in this scope [E0412] +{ + fn from(text: T) -> Self { + LabelText::Plain(text.into()) + } +} + +fn main() {} diff --git a/src/test/ui/trait-bounds/impl-bound-with-references-error.stderr b/src/test/ui/trait-bounds/impl-bound-with-references-error.stderr new file mode 100644 index 00000000000..95fd6bd504c --- /dev/null +++ b/src/test/ui/trait-bounds/impl-bound-with-references-error.stderr @@ -0,0 +1,24 @@ +error[E0412]: cannot find type `Cow` in this scope + --> $DIR/impl-bound-with-references-error.rs:12:13 + | +LL | T: Into>, + | ^^^ not found in this scope + | +help: consider importing this enum + | +LL | use std::borrow::Cow; + | + +error[E0119]: conflicting implementations of trait `From` for type `LabelText` + --> $DIR/impl-bound-with-references-error.rs:9:1 + | +LL | impl From for LabelText + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | + = note: conflicting implementation in crate `core`: + - impl From for T; + +error: aborting due to 2 previous errors + +Some errors have detailed explanations: E0119, E0412. +For more information about an error, try `rustc --explain E0119`.