diff --git a/compiler/rustc_trait_selection/src/traits/select/mod.rs b/compiler/rustc_trait_selection/src/traits/select/mod.rs index f5be8bf0949e6..8adf9015933c3 100644 --- a/compiler/rustc_trait_selection/src/traits/select/mod.rs +++ b/compiler/rustc_trait_selection/src/traits/select/mod.rs @@ -1487,10 +1487,11 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { ) => false, (ParamCandidate(other), ParamCandidate(victim)) => { - let value_same_except_bound_vars = other.value.skip_binder() + let same_except_bound_vars = other.value.skip_binder() == victim.value.skip_binder() + && other.constness == victim.constness && !other.value.skip_binder().has_escaping_bound_vars(); - if value_same_except_bound_vars { + if same_except_bound_vars { // See issue #84398. In short, we can generate multiple ParamCandidates which are // the same except for unused bound vars. Just pick the one with the fewest bound vars // or the current one if tied (they should both evaluate to the same answer). This is diff --git a/src/test/ui/rfc-2632-const-trait-impl/call-generic-method-dup-bound.rs b/src/test/ui/rfc-2632-const-trait-impl/call-generic-method-dup-bound.rs index 7185376b440c8..cc24dbd96d253 100644 --- a/src/test/ui/rfc-2632-const-trait-impl/call-generic-method-dup-bound.rs +++ b/src/test/ui/rfc-2632-const-trait-impl/call-generic-method-dup-bound.rs @@ -16,12 +16,17 @@ impl const PartialEq for S { // This duplicate bound should not result in ambiguities. It should be equivalent to a single ~const // bound. -// const fn equals_self(t: &T) -> bool { -// FIXME(fee1-dead)^ why should the order matter here? -const fn equals_self(t: &T) -> bool { +const fn equals_self(t: &T) -> bool { *t == *t } -pub const EQ: bool = equals_self(&S); +trait A: PartialEq {} +impl A for T {} + +const fn equals_self2(t: &T) -> bool { + *t == *t +} + +pub const EQ: bool = equals_self(&S) && equals_self2(&S); fn main() {}