Skip to content
Merged
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
25 changes: 16 additions & 9 deletions compiler/rustc_hir_typeck/src/expr.rs
Original file line number Diff line number Diff line change
Expand Up @@ -2821,7 +2821,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
// but has nested obligations which are unsatisfied.
for (base_t, _) in self.autoderef(base.span, base_t).silence_errors() {
if let Some((_, index_ty, element_ty)) =
self.find_and_report_unsatisfied_index_impl(expr.hir_id, base, base_t)
self.find_and_report_unsatisfied_index_impl(base, base_t)
{
self.demand_coerce(idx, idx_t, index_ty, None, AllowTwoPhase::No);
return element_ty;
Expand Down Expand Up @@ -2880,7 +2880,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
/// predicates cause this to be, so that the user can add them to fix their code.
fn find_and_report_unsatisfied_index_impl(
&self,
index_expr_hir_id: HirId,
base_expr: &hir::Expr<'_>,
base_ty: Ty<'tcx>,
) -> Option<(ErrorGuaranteed, Ty<'tcx>, Ty<'tcx>)> {
Expand Down Expand Up @@ -2913,13 +2912,21 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
// in the first place.
ocx.register_obligations(traits::predicates_for_generics(
|idx, span| {
traits::ObligationCause::new(
base_expr.span,
self.body_id,
if span.is_dummy() {
traits::ExprItemObligation(impl_def_id, index_expr_hir_id, idx)
} else {
traits::ExprBindingObligation(impl_def_id, span, index_expr_hir_id, idx)
cause.clone().derived_cause(
ty::Binder::dummy(ty::TraitPredicate {
trait_ref: impl_trait_ref,
polarity: ty::ImplPolarity::Positive,
constness: ty::BoundConstness::NotConst,
}),
|derived| {
traits::ImplDerivedObligation(Box::new(
traits::ImplDerivedObligationCause {
derived,
impl_or_alias_def_id: impl_def_id,
impl_def_predicate_index: Some(idx),
span,
},
))
},
)
},
Expand Down
18 changes: 12 additions & 6 deletions tests/ui/typeck/bad-index-due-to-nested.stderr
Original file line number Diff line number Diff line change
Expand Up @@ -4,11 +4,14 @@ error[E0277]: the trait bound `K: Hash` is not satisfied
LL | map[k]
| ^^^ the trait `Hash` is not implemented for `K`
|
note: required by a bound in `<HashMap<K, V> as Index<&K>>`
--> $DIR/bad-index-due-to-nested.rs:9:8
note: required for `HashMap<K, V>` to implement `Index<&K>`
--> $DIR/bad-index-due-to-nested.rs:7:12
|
LL | impl<K, V> Index<&K> for HashMap<K, V>
| ^^^^^^^^^ ^^^^^^^^^^^^^
LL | where
LL | K: Hash,
| ^^^^ required by this bound in `<HashMap<K, V> as Index<&K>>`
| ---- unsatisfied trait bound introduced here
help: consider restricting type parameter `K`
|
LL | fn index<'a, K: std::hash::Hash, V>(map: &'a HashMap<K, V>, k: K) -> &'a V {
Expand All @@ -20,11 +23,14 @@ error[E0277]: the trait bound `V: Copy` is not satisfied
LL | map[k]
| ^^^ the trait `Copy` is not implemented for `V`
|
note: required by a bound in `<HashMap<K, V> as Index<&K>>`
--> $DIR/bad-index-due-to-nested.rs:10:8
note: required for `HashMap<K, V>` to implement `Index<&K>`
--> $DIR/bad-index-due-to-nested.rs:7:12
|
LL | impl<K, V> Index<&K> for HashMap<K, V>
| ^^^^^^^^^ ^^^^^^^^^^^^^
...
LL | V: Copy,
| ^^^^ required by this bound in `<HashMap<K, V> as Index<&K>>`
| ---- unsatisfied trait bound introduced here
help: consider restricting type parameter `V`
|
LL | fn index<'a, K, V: std::marker::Copy>(map: &'a HashMap<K, V>, k: K) -> &'a V {
Expand Down