diff options
Diffstat (limited to 'compiler/rustc_trait_selection')
| -rw-r--r-- | compiler/rustc_trait_selection/src/traits/dyn_compatibility.rs | 27 |
1 files changed, 23 insertions, 4 deletions
diff --git a/compiler/rustc_trait_selection/src/traits/dyn_compatibility.rs b/compiler/rustc_trait_selection/src/traits/dyn_compatibility.rs index ea1eed95723..4b493c95d59 100644 --- a/compiler/rustc_trait_selection/src/traits/dyn_compatibility.rs +++ b/compiler/rustc_trait_selection/src/traits/dyn_compatibility.rs @@ -106,6 +106,10 @@ fn dyn_compatibility_violations_for_trait( if !spans.is_empty() { violations.push(DynCompatibilityViolation::SupertraitNonLifetimeBinder(spans)); } + let spans = super_predicates_are_unconditionally_const(tcx, trait_def_id); + if !spans.is_empty() { + violations.push(DynCompatibilityViolation::SupertraitConst(spans)); + } violations } @@ -247,16 +251,31 @@ fn super_predicates_have_non_lifetime_binders( tcx: TyCtxt<'_>, trait_def_id: DefId, ) -> SmallVec<[Span; 1]> { - // If non_lifetime_binders is disabled, then exit early - if !tcx.features().non_lifetime_binders() { - return SmallVec::new(); - } tcx.explicit_super_predicates_of(trait_def_id) .iter_identity_copied() .filter_map(|(pred, span)| pred.has_non_region_bound_vars().then_some(span)) .collect() } +/// Checks for `const Trait` supertraits. We're okay with `[const] Trait`, +/// supertraits since for a non-const instantiation of that trait, the +/// conditionally-const supertrait is also not required to be const. +fn super_predicates_are_unconditionally_const( + tcx: TyCtxt<'_>, + trait_def_id: DefId, +) -> SmallVec<[Span; 1]> { + tcx.explicit_super_predicates_of(trait_def_id) + .iter_identity_copied() + .filter_map(|(pred, span)| { + if let ty::ClauseKind::HostEffect(_) = pred.kind().skip_binder() { + Some(span) + } else { + None + } + }) + .collect() +} + fn trait_has_sized_self(tcx: TyCtxt<'_>, trait_def_id: DefId) -> bool { tcx.generics_require_sized_self(trait_def_id) } |