Skip to content

Commit

Permalink
Auto merge of #132798 - workingjubilee:rollup-qxvmmqo, r=workingjubilee
Browse files Browse the repository at this point in the history 
Rollup of 5 pull requests

Successful merges:

 - #132755 (Do not reveal opaques in the param-env, we got lazy norm instead)
 - #132757 (Get rid of `check_opaque_type_well_formed`)
 - #132760 (Don't suggest `.into_iter()` on iterators)
 - #132778 (update io::Error::into_inner to acknowledge io::Error::other)
 - #132780 (use verbose for path separator suggestion)

r? `@ghost`
`@rustbot` modify labels: rollup
  • Loading branch information
@bors
bors committed Nov 9, 2024
2 parents 012ae13 + c4922f1 commit 62bb2ac
Show file tree
Hide file tree
Showing 47 changed files with 559 additions and 445 deletions.
90 changes: 1 addition & 89 deletions compiler/rustc_borrowck/src/region_infer/opaque_types.rs
View file
Original file line number Diff line number Diff line change
@@ -1,18 +1,14 @@
use rustc_data_structures::fx::FxIndexMap;
use rustc_errors::ErrorGuaranteed;
use rustc_hir::OpaqueTyOrigin;
use rustc_hir::def::DefKind;
use rustc_hir::def_id::LocalDefId;
use rustc_infer::infer::{InferCtxt, NllRegionVariableOrigin, TyCtxtInferExt as _};
use rustc_infer::traits::{Obligation, ObligationCause};
use rustc_macros::extension;
use rustc_middle::ty::visit::TypeVisitableExt;
use rustc_middle::ty::{
self, GenericArgKind, GenericArgs, OpaqueHiddenType, OpaqueTypeKey, Ty, TyCtxt, TypeFoldable,
TypingMode,
};
use rustc_span::Span;
use rustc_trait_selection::error_reporting::InferCtxtErrorExt;
use rustc_trait_selection::traits::ObligationCtxt;
use tracing::{debug, instrument};

Expand Down Expand Up @@ -303,91 +299,7 @@ impl<'tcx> InferCtxt<'tcx> {
return Ty::new_error(self.tcx, e);
}

// `definition_ty` does not live in of the current inference context,
// so lets make sure that we don't accidentally misuse our current `infcx`.
match check_opaque_type_well_formed(
self.tcx,
self.next_trait_solver(),
opaque_type_key.def_id,
instantiated_ty.span,
definition_ty,
) {
Ok(hidden_ty) => hidden_ty,
Err(guar) => Ty::new_error(self.tcx, guar),
}
}
}

/// This logic duplicates most of `check_opaque_meets_bounds`.
/// FIXME(oli-obk): Also do region checks here and then consider removing
/// `check_opaque_meets_bounds` entirely.
fn check_opaque_type_well_formed<'tcx>(
tcx: TyCtxt<'tcx>,
next_trait_solver: bool,
def_id: LocalDefId,
definition_span: Span,
definition_ty: Ty<'tcx>,
) -> Result<Ty<'tcx>, ErrorGuaranteed> {
// Only check this for TAIT. RPIT already supports `tests/ui/impl-trait/nested-return-type2.rs`
// on stable and we'd break that.
let opaque_ty_hir = tcx.hir().expect_opaque_ty(def_id);
let OpaqueTyOrigin::TyAlias { .. } = opaque_ty_hir.origin else {
return Ok(definition_ty);
};
let param_env = tcx.param_env(def_id);

let mut parent_def_id = def_id;
while tcx.def_kind(parent_def_id) == DefKind::OpaqueTy {
parent_def_id = tcx.local_parent(parent_def_id);
}

// FIXME(#132279): This should eventually use the already defined hidden types
// instead. Alternatively we'll entirely remove this function given we also check
// the opaque in `check_opaque_meets_bounds` later.
let infcx = tcx
.infer_ctxt()
.with_next_trait_solver(next_trait_solver)
.build(TypingMode::analysis_in_body(tcx, parent_def_id));
let ocx = ObligationCtxt::new_with_diagnostics(&infcx);
let identity_args = GenericArgs::identity_for_item(tcx, def_id);

// Require that the hidden type actually fulfills all the bounds of the opaque type, even without
// the bounds that the function supplies.
let opaque_ty = Ty::new_opaque(tcx, def_id.to_def_id(), identity_args);
ocx.eq(&ObligationCause::misc(definition_span, def_id), param_env, opaque_ty, definition_ty)
.map_err(|err| {
infcx
.err_ctxt()
.report_mismatched_types(
&ObligationCause::misc(definition_span, def_id),
param_env,
opaque_ty,
definition_ty,
err,
)
.emit()
})?;

// Require the hidden type to be well-formed with only the generics of the opaque type.
// Defining use functions may have more bounds than the opaque type, which is ok, as long as the
// hidden type is well formed even without those bounds.
let predicate = ty::Binder::dummy(ty::PredicateKind::Clause(ty::ClauseKind::WellFormed(
definition_ty.into(),
)));
ocx.register_obligation(Obligation::misc(tcx, definition_span, def_id, param_env, predicate));

// Check that all obligations are satisfied by the implementation's
// version.
let errors = ocx.select_all_or_error();

// This is fishy, but we check it again in `check_opaque_meets_bounds`.
// Remove once we can prepopulate with known hidden types.
let _ = infcx.take_opaque_types();

if errors.is_empty() {
Ok(definition_ty)
} else {
Err(infcx.err_ctxt().report_fulfillment_errors(errors))
definition_ty
}
}

Expand Down
155 changes: 136 additions & 19 deletions compiler/rustc_hir_analysis/src/check/check.rs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -5,13 +5,14 @@ use rustc_abi::FieldIdx;
use rustc_data_structures::unord::{UnordMap, UnordSet};
use rustc_errors::MultiSpan;
use rustc_errors::codes::*;
use rustc_hir::Node;
use rustc_hir::def::{CtorKind, DefKind};
use rustc_hir::{Node, intravisit};
use rustc_infer::infer::{RegionVariableOrigin, TyCtxtInferExt};
use rustc_infer::traits::Obligation;
use rustc_infer::traits::{Obligation, ObligationCauseCode};
use rustc_lint_defs::builtin::{
REPR_TRANSPARENT_EXTERNAL_PRIVATE_FIELDS, UNSUPPORTED_FN_PTR_CALLING_CONVENTIONS,
};
use rustc_middle::hir::nested_filter;
use rustc_middle::middle::resolve_bound_vars::ResolvedArg;
use rustc_middle::middle::stability::EvalResult;
use rustc_middle::span_bug;
Expand Down Expand Up @@ -190,7 +191,7 @@ fn check_static_inhabited(tcx: TyCtxt<'_>, def_id: LocalDefId) {
/// Checks that an opaque type does not contain cycles and does not use `Self` or `T::Foo`
/// projections that would result in "inheriting lifetimes".
fn check_opaque(tcx: TyCtxt<'_>, def_id: LocalDefId) {
let hir::OpaqueTy { origin, .. } = tcx.hir().expect_opaque_ty(def_id);
let hir::OpaqueTy { origin, .. } = *tcx.hir().expect_opaque_ty(def_id);

// HACK(jynelson): trying to infer the type of `impl trait` breaks documenting
// `async-std` (and `pub async fn` in general).
Expand All @@ -200,23 +201,20 @@ fn check_opaque(tcx: TyCtxt<'_>, def_id: LocalDefId) {
return;
}

let span = tcx.def_span(def_id);

if tcx.type_of(def_id).instantiate_identity().references_error() {
return;
}
if check_opaque_for_cycles(tcx, def_id, span).is_err() {
if check_opaque_for_cycles(tcx, def_id).is_err() {
return;
}

let _ = check_opaque_meets_bounds(tcx, def_id, span, origin);
let _ = check_opaque_meets_bounds(tcx, def_id, origin);
}

/// Checks that an opaque type does not contain cycles.
pub(super) fn check_opaque_for_cycles<'tcx>(
tcx: TyCtxt<'tcx>,
def_id: LocalDefId,
span: Span,
) -> Result<(), ErrorGuaranteed> {
let args = GenericArgs::identity_for_item(tcx, def_id);

Expand All @@ -233,7 +231,7 @@ pub(super) fn check_opaque_for_cycles<'tcx>(
.try_expand_impl_trait_type(def_id.to_def_id(), args, InspectCoroutineFields::No)
.is_err()
{
let reported = opaque_type_cycle_error(tcx, def_id, span);
let reported = opaque_type_cycle_error(tcx, def_id);
return Err(reported);
}

Expand Down Expand Up @@ -267,10 +265,16 @@ pub(super) fn check_opaque_for_cycles<'tcx>(
fn check_opaque_meets_bounds<'tcx>(
tcx: TyCtxt<'tcx>,
def_id: LocalDefId,
span: Span,
origin: &hir::OpaqueTyOrigin<LocalDefId>,
origin: hir::OpaqueTyOrigin<LocalDefId>,
) -> Result<(), ErrorGuaranteed> {
let defining_use_anchor = match *origin {
let (span, definition_def_id) =
if let Some((span, def_id)) = best_definition_site_of_opaque(tcx, def_id, origin) {
(span, Some(def_id))
} else {
(tcx.def_span(def_id), None)
};

let defining_use_anchor = match origin {
hir::OpaqueTyOrigin::FnReturn { parent, .. }
| hir::OpaqueTyOrigin::AsyncFn { parent, .. }
| hir::OpaqueTyOrigin::TyAlias { parent, .. } => parent,
Expand All @@ -281,7 +285,7 @@ fn check_opaque_meets_bounds<'tcx>(
let infcx = tcx.infer_ctxt().build(TypingMode::analysis_in_body(tcx, defining_use_anchor));
let ocx = ObligationCtxt::new_with_diagnostics(&infcx);

let args = match *origin {
let args = match origin {
hir::OpaqueTyOrigin::FnReturn { parent, .. }
| hir::OpaqueTyOrigin::AsyncFn { parent, .. }
| hir::OpaqueTyOrigin::TyAlias { parent, .. } => GenericArgs::identity_for_item(
Expand All @@ -306,8 +310,33 @@ fn check_opaque_meets_bounds<'tcx>(
_ => re,
});

let misc_cause = traits::ObligationCause::misc(span, def_id);
// HACK: We eagerly instantiate some bounds to report better errors for them...
// This isn't necessary for correctness, since we register these bounds when
// equating the opaque below, but we should clean this up in the new solver.
for (predicate, pred_span) in
tcx.explicit_item_bounds(def_id).iter_instantiated_copied(tcx, args)
{
let predicate = predicate.fold_with(&mut BottomUpFolder {
tcx,
ty_op: |ty| if ty == opaque_ty { hidden_ty } else { ty },
lt_op: |lt| lt,
ct_op: |ct| ct,
});

ocx.register_obligation(Obligation::new(
tcx,
ObligationCause::new(
span,
def_id,
ObligationCauseCode::OpaqueTypeBound(pred_span, definition_def_id),
),
param_env,
predicate,
));
}

let misc_cause = ObligationCause::misc(span, def_id);
// FIXME: We should just register the item bounds here, rather than equating.
match ocx.eq(&misc_cause, param_env, opaque_ty, hidden_ty) {
Ok(()) => {}
Err(ty_err) => {
Expand Down Expand Up @@ -364,6 +393,97 @@ fn check_opaque_meets_bounds<'tcx>(
}
}

fn best_definition_site_of_opaque<'tcx>(
tcx: TyCtxt<'tcx>,
opaque_def_id: LocalDefId,
origin: hir::OpaqueTyOrigin<LocalDefId>,
) -> Option<(Span, LocalDefId)> {
struct TaitConstraintLocator<'tcx> {
opaque_def_id: LocalDefId,
tcx: TyCtxt<'tcx>,
}
impl<'tcx> TaitConstraintLocator<'tcx> {
fn check(&self, item_def_id: LocalDefId) -> ControlFlow<(Span, LocalDefId)> {
if !self.tcx.has_typeck_results(item_def_id) {
return ControlFlow::Continue(());
}

if let Some(hidden_ty) =
self.tcx.mir_borrowck(item_def_id).concrete_opaque_types.get(&self.opaque_def_id)
{
ControlFlow::Break((hidden_ty.span, item_def_id))
} else {
ControlFlow::Continue(())
}
}
}
impl<'tcx> intravisit::Visitor<'tcx> for TaitConstraintLocator<'tcx> {
type NestedFilter = nested_filter::All;
type Result = ControlFlow<(Span, LocalDefId)>;
fn nested_visit_map(&mut self) -> Self::Map {
self.tcx.hir()
}
fn visit_expr(&mut self, ex: &'tcx hir::Expr<'tcx>) -> Self::Result {
if let hir::ExprKind::Closure(closure) = ex.kind {
self.check(closure.def_id)?;
}
intravisit::walk_expr(self, ex)
}
fn visit_item(&mut self, it: &'tcx hir::Item<'tcx>) -> Self::Result {
self.check(it.owner_id.def_id)?;
intravisit::walk_item(self, it)
}
fn visit_impl_item(&mut self, it: &'tcx hir::ImplItem<'tcx>) -> Self::Result {
self.check(it.owner_id.def_id)?;
intravisit::walk_impl_item(self, it)
}
fn visit_trait_item(&mut self, it: &'tcx hir::TraitItem<'tcx>) -> Self::Result {
self.check(it.owner_id.def_id)?;
intravisit::walk_trait_item(self, it)
}
fn visit_foreign_item(&mut self, it: &'tcx hir::ForeignItem<'tcx>) -> Self::Result {
intravisit::walk_foreign_item(self, it)
}
}

let mut locator = TaitConstraintLocator { tcx, opaque_def_id };
match origin {
hir::OpaqueTyOrigin::FnReturn { parent, .. }
| hir::OpaqueTyOrigin::AsyncFn { parent, .. } => locator.check(parent).break_value(),
hir::OpaqueTyOrigin::TyAlias { parent, in_assoc_ty: true } => {
let impl_def_id = tcx.local_parent(parent);
for assoc in tcx.associated_items(impl_def_id).in_definition_order() {
match assoc.kind {
ty::AssocKind::Const | ty::AssocKind::Fn => {
if let ControlFlow::Break(span) = locator.check(assoc.def_id.expect_local())
{
return Some(span);
}
}
ty::AssocKind::Type => {}
}
}

None
}
hir::OpaqueTyOrigin::TyAlias { in_assoc_ty: false, .. } => {
let scope = tcx.hir().get_defining_scope(tcx.local_def_id_to_hir_id(opaque_def_id));
let found = if scope == hir::CRATE_HIR_ID {
tcx.hir().walk_toplevel_module(&mut locator)
} else {
match tcx.hir_node(scope) {
Node::Item(it) => locator.visit_item(it),
Node::ImplItem(it) => locator.visit_impl_item(it),
Node::TraitItem(it) => locator.visit_trait_item(it),
Node::ForeignItem(it) => locator.visit_foreign_item(it),
other => bug!("{:?} is not a valid scope for an opaque type item", other),
}
};
found.break_value()
}
}
}

fn sanity_check_found_hidden_type<'tcx>(
tcx: TyCtxt<'tcx>,
key: ty::OpaqueTypeKey<'tcx>,
Expand Down Expand Up @@ -1535,11 +1655,8 @@ fn check_type_alias_type_params_are_used<'tcx>(tcx: TyCtxt<'tcx>, def_id: LocalD
///
/// If all the return expressions evaluate to `!`, then we explain that the error will go away
/// after changing it. This can happen when a user uses `panic!()` or similar as a placeholder.
fn opaque_type_cycle_error(
tcx: TyCtxt<'_>,
opaque_def_id: LocalDefId,
span: Span,
) -> ErrorGuaranteed {
fn opaque_type_cycle_error(tcx: TyCtxt<'_>, opaque_def_id: LocalDefId) -> ErrorGuaranteed {
let span = tcx.def_span(opaque_def_id);
let mut err = struct_span_code_err!(tcx.dcx(), span, E0720, "cannot resolve opaque type");

let mut label = false;
Expand Down
Loading

0 comments on commit 62bb2ac

Please sign in to comment.