diff options
| -rw-r--r-- | compiler/rustc_trait_selection/src/solve/trait_goals.rs | 14 | ||||
| -rw-r--r-- | tests/ui/traits/new-solver/unsafe-auto-trait-impl.rs | 8 |
2 files changed, 22 insertions, 0 deletions
diff --git a/compiler/rustc_trait_selection/src/solve/trait_goals.rs b/compiler/rustc_trait_selection/src/solve/trait_goals.rs index abb69476cae..6554c739b3f 100644 --- a/compiler/rustc_trait_selection/src/solve/trait_goals.rs +++ b/compiler/rustc_trait_selection/src/solve/trait_goals.rs @@ -89,6 +89,20 @@ impl<'tcx> assembly::GoalKind<'tcx> for TraitPredicate<'tcx> { ecx: &mut EvalCtxt<'_, 'tcx>, goal: Goal<'tcx, Self>, ) -> QueryResult<'tcx> { + // This differs from the current stable behavior and + // fixes #84857. Due to breakage found via crater, we + // currently instead lint patterns which can be used to + // exploit this unsoundness on stable, see #93367 for + // more details. + if let Some(def_id) = ecx.tcx().find_map_relevant_impl( + goal.predicate.def_id(), + goal.predicate.self_ty(), + Some, + ) { + debug!(?def_id, ?goal, "disqualified auto-trait implementation"); + return Err(NoSolution); + } + ecx.probe_and_evaluate_goal_for_constituent_tys( goal, structural_traits::instantiate_constituent_tys_for_auto_trait, diff --git a/tests/ui/traits/new-solver/unsafe-auto-trait-impl.rs b/tests/ui/traits/new-solver/unsafe-auto-trait-impl.rs new file mode 100644 index 00000000000..bcfc747ebb1 --- /dev/null +++ b/tests/ui/traits/new-solver/unsafe-auto-trait-impl.rs @@ -0,0 +1,8 @@ +// compile-flags: -Ztrait-solver=next +// check-pass + +struct Foo(*mut ()); + +unsafe impl Sync for Foo {} + +fn main() {} |