tcx.mk_adt(def, substs)
}
ItemKind::OpaqueTy(OpaqueTy { origin: hir::OpaqueTyOrigin::TyAlias, .. }) => {
- find_opaque_ty_constraints(tcx, def_id)
+ find_opaque_ty_constraints_for_tait(tcx, def_id)
}
// Opaque types desugared from `impl Trait`.
ItemKind::OpaqueTy(OpaqueTy { origin: hir::OpaqueTyOrigin::FnReturn(owner) | hir::OpaqueTyOrigin::AsyncFn(owner), .. }) => {
- let concrete_ty = tcx
- .mir_borrowck(owner)
- .concrete_opaque_types
- .get(&def_id.to_def_id())
- .copied()
- .map(|concrete| concrete.ty)
- .unwrap_or_else(|| {
- let table = tcx.typeck(owner);
- if let Some(_) = table.tainted_by_errors {
- // Some error in the
- // owner fn prevented us from populating
- // the `concrete_opaque_types` table.
- tcx.ty_error()
- } else {
- table.concrete_opaque_types.get(&def_id.to_def_id()).copied().unwrap_or_else(|| {
- // We failed to resolve the opaque type or it
- // resolves to itself. We interpret this as the
- // no values of the hidden type ever being constructed,
- // so we can just make the hidden type be `!`.
- // For backwards compatibility reasons, we fall back to
- // `()` until we the diverging default is changed.
- Some(tcx.mk_diverging_default())
- }).expect("RPIT always have a hidden type from typeck")
- }
- });
- debug!("concrete_ty = {:?}", concrete_ty);
- concrete_ty
+ find_opaque_ty_constraints_for_rpit(tcx, def_id, owner)
}
ItemKind::Trait(..)
| ItemKind::TraitAlias(..)
/// fn b<T>() -> Foo<T, u32> { .. }
/// ```
///
-fn find_opaque_ty_constraints(tcx: TyCtxt<'_>, def_id: LocalDefId) -> Ty<'_> {
+fn find_opaque_ty_constraints_for_tait(tcx: TyCtxt<'_>, def_id: LocalDefId) -> Ty<'_> {
use rustc_hir::{Expr, ImplItem, Item, TraitItem};
struct ConstraintLocator<'tcx> {
tcx: TyCtxt<'tcx>,
/// def_id of the opaque type whose defining uses are being checked
- def_id: DefId,
+ def_id: LocalDefId,
/// as we walk the defining uses, we are checking that all of them
/// define the same hidden type. This variable is set to `Some`
impl ConstraintLocator<'_> {
#[instrument(skip(self), level = "debug")]
- fn check(&mut self, def_id: LocalDefId) {
+ fn check(&mut self, item_def_id: LocalDefId) {
// Don't try to check items that cannot possibly constrain the type.
- if !self.tcx.has_typeck_results(def_id) {
+ if !self.tcx.has_typeck_results(item_def_id) {
debug!("no constraint: no typeck results");
return;
}
// // because we again need to reveal `Foo` so we can check whether the
// // constant does not contain interior mutability.
// ```
- let tables = self.tcx.typeck(def_id);
+ let tables = self.tcx.typeck(item_def_id);
if let Some(_) = tables.tainted_by_errors {
self.found = Some(ty::OpaqueHiddenType { span: DUMMY_SP, ty: self.tcx.ty_error() });
return;
}
- if tables.concrete_opaque_types.get(&self.def_id).is_none() {
+ if !tables.concrete_opaque_types.contains_key(&self.def_id) {
debug!("no constraints in typeck results");
return;
}
// Use borrowck to get the type with unerased regions.
- let concrete_opaque_types = &self.tcx.mir_borrowck(def_id).concrete_opaque_types;
+ let concrete_opaque_types = &self.tcx.mir_borrowck(item_def_id).concrete_opaque_types;
debug!(?concrete_opaque_types);
- for &(def_id, concrete_type) in concrete_opaque_types {
- if def_id != self.def_id {
- // Ignore constraints for other opaque types.
- continue;
- }
-
+ if let Some(&concrete_type) = concrete_opaque_types.get(&self.def_id) {
debug!(?concrete_type, "found constraint");
-
if let Some(prev) = self.found {
if concrete_type.ty != prev.ty && !(concrete_type, prev).references_error() {
prev.report_mismatch(&concrete_type, self.tcx);
fn visit_item(&mut self, it: &'tcx Item<'tcx>) {
trace!(?it.def_id);
// The opaque type itself or its children are not within its reveal scope.
- if it.def_id.to_def_id() != self.def_id {
+ if it.def_id != self.def_id {
self.check(it.def_id);
intravisit::walk_item(self, it);
}
fn visit_impl_item(&mut self, it: &'tcx ImplItem<'tcx>) {
trace!(?it.def_id);
// The opaque type itself or its children are not within its reveal scope.
- if it.def_id.to_def_id() != self.def_id {
+ if it.def_id != self.def_id {
self.check(it.def_id);
intravisit::walk_impl_item(self, it);
}
let hir_id = tcx.hir().local_def_id_to_hir_id(def_id);
let scope = tcx.hir().get_defining_scope(hir_id);
- let mut locator = ConstraintLocator { def_id: def_id.to_def_id(), tcx, found: None };
+ let mut locator = ConstraintLocator { def_id: def_id, tcx, found: None };
debug!(?scope);
}
}
+fn find_opaque_ty_constraints_for_rpit(
+ tcx: TyCtxt<'_>,
+ def_id: LocalDefId,
+ owner_def_id: LocalDefId,
+) -> Ty<'_> {
+ use rustc_hir::{Expr, ImplItem, Item, TraitItem};
+
+ struct ConstraintChecker<'tcx> {
+ tcx: TyCtxt<'tcx>,
+
+ /// def_id of the opaque type whose defining uses are being checked
+ def_id: LocalDefId,
+
+ found: ty::OpaqueHiddenType<'tcx>,
+ }
+
+ impl ConstraintChecker<'_> {
+ #[instrument(skip(self), level = "debug")]
+ fn check(&self, def_id: LocalDefId) {
+ // Use borrowck to get the type with unerased regions.
+ let concrete_opaque_types = &self.tcx.mir_borrowck(def_id).concrete_opaque_types;
+ debug!(?concrete_opaque_types);
+ for &(def_id, concrete_type) in concrete_opaque_types {
+ if def_id != self.def_id {
+ // Ignore constraints for other opaque types.
+ continue;
+ }
+
+ debug!(?concrete_type, "found constraint");
+
+ if concrete_type.ty != self.found.ty
+ && !(concrete_type, self.found).references_error()
+ {
+ self.found.report_mismatch(&concrete_type, self.tcx);
+ }
+ }
+ }
+ }
+
+ impl<'tcx> intravisit::Visitor<'tcx> for ConstraintChecker<'tcx> {
+ type NestedFilter = nested_filter::OnlyBodies;
+
+ fn nested_visit_map(&mut self) -> Self::Map {
+ self.tcx.hir()
+ }
+ fn visit_expr(&mut self, ex: &'tcx Expr<'tcx>) {
+ if let hir::ExprKind::Closure { .. } = ex.kind {
+ let def_id = self.tcx.hir().local_def_id(ex.hir_id);
+ self.check(def_id);
+ }
+ intravisit::walk_expr(self, ex);
+ }
+ fn visit_item(&mut self, it: &'tcx Item<'tcx>) {
+ trace!(?it.def_id);
+ // The opaque type itself or its children are not within its reveal scope.
+ if it.def_id != self.def_id {
+ self.check(it.def_id);
+ intravisit::walk_item(self, it);
+ }
+ }
+ fn visit_impl_item(&mut self, it: &'tcx ImplItem<'tcx>) {
+ trace!(?it.def_id);
+ // The opaque type itself or its children are not within its reveal scope.
+ if it.def_id != self.def_id {
+ self.check(it.def_id);
+ intravisit::walk_impl_item(self, it);
+ }
+ }
+ fn visit_trait_item(&mut self, it: &'tcx TraitItem<'tcx>) {
+ trace!(?it.def_id);
+ self.check(it.def_id);
+ intravisit::walk_trait_item(self, it);
+ }
+ }
+
+ let concrete = tcx.mir_borrowck(owner_def_id).concrete_opaque_types.get(&def_id).copied();
+
+ if let Some(concrete) = concrete {
+ let scope = tcx.hir().local_def_id_to_hir_id(owner_def_id);
+ debug!(?scope);
+ let mut locator = ConstraintChecker { def_id: def_id, tcx, found: concrete };
+
+ match tcx.hir().get(scope) {
+ Node::Item(it) => intravisit::walk_item(&mut locator, it),
+ Node::ImplItem(it) => intravisit::walk_impl_item(&mut locator, it),
+ Node::TraitItem(it) => intravisit::walk_trait_item(&mut locator, it),
+ other => bug!("{:?} is not a valid scope for an opaque type item", other),
+ }
+ }
+
+ concrete.map(|concrete| concrete.ty).unwrap_or_else(|| {
+ let table = tcx.typeck(owner_def_id);
+ if let Some(_) = table.tainted_by_errors {
+ // Some error in the
+ // owner fn prevented us from populating
+ // the `concrete_opaque_types` table.
+ tcx.ty_error()
+ } else {
+ table
+ .concrete_opaque_types
+ .get(&def_id)
+ .copied()
+ .unwrap_or_else(|| {
+ // We failed to resolve the opaque type or it
+ // resolves to itself. We interpret this as the
+ // no values of the hidden type ever being constructed,
+ // so we can just make the hidden type be `!`.
+ // For backwards compatibility reasons, we fall back to
+ // `()` until we the diverging default is changed.
+ Some(tcx.mk_diverging_default())
+ })
+ .expect("RPIT always have a hidden type from typeck")
+ }
+ })
+}
+
fn infer_placeholder_type<'a>(
tcx: TyCtxt<'a>,
def_id: LocalDefId,
projects / rust.git / blobdiff