Auto merge of #76244 - vandenheuvel:remove__paramenv__def_id, r=nikomatsakis

Removing the `def_id` field from hot `ParamEnv` to make it smaller

This PR addresses https://github.com/rust-lang/rust/issues/74865.
This commit is contained in:
bors 2020-09-13 16:28:22 +00:00
commit 7402a39447
35 changed files with 288 additions and 337 deletions

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@ -26,7 +26,8 @@ pub fn explicit_outlives_bounds<'tcx>(
| ty::PredicateAtom::ClosureKind(..)
| ty::PredicateAtom::TypeOutlives(..)
| ty::PredicateAtom::ConstEvaluatable(..)
| ty::PredicateAtom::ConstEquate(..) => None,
| ty::PredicateAtom::ConstEquate(..)
| ty::PredicateAtom::TypeWellFormedFromEnv(..) => None,
ty::PredicateAtom::RegionOutlives(ty::OutlivesPredicate(r_a, r_b)) => {
Some(OutlivesBound::RegionSubRegion(r_b, r_a))
}

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@ -57,7 +57,7 @@ pub type TraitObligation<'tcx> = Obligation<'tcx, ty::PolyTraitPredicate<'tcx>>;
// `PredicateObligation` is used a lot. Make sure it doesn't unintentionally get bigger.
#[cfg(target_arch = "x86_64")]
static_assert_size!(PredicateObligation<'_>, 40);
static_assert_size!(PredicateObligation<'_>, 32);
pub type Obligations<'tcx, O> = Vec<Obligation<'tcx, O>>;
pub type PredicateObligations<'tcx> = Vec<PredicateObligation<'tcx>>;

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@ -236,6 +236,9 @@ impl Elaborator<'tcx> {
.map(|predicate| predicate_obligation(predicate, None)),
);
}
ty::PredicateAtom::TypeWellFormedFromEnv(..) => {
// Nothing to elaborate
}
}
}
}

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@ -1228,7 +1228,8 @@ impl<'tcx> LateLintPass<'tcx> for TrivialConstraints {
ClosureKind(..) |
Subtype(..) |
ConstEvaluatable(..) |
ConstEquate(..) => continue,
ConstEquate(..) |
TypeWellFormedFromEnv(..) => continue,
};
if predicate.is_global() {
cx.struct_span_lint(TRIVIAL_BOUNDS, span, |lint| {

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@ -1399,7 +1399,7 @@ rustc_queries! {
}
query evaluate_goal(
goal: traits::ChalkCanonicalGoal<'tcx>
goal: traits::CanonicalChalkEnvironmentAndGoal<'tcx>
) -> Result<
&'tcx Canonical<'tcx, canonical::QueryResponse<'tcx, ()>>,
NoSolution

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@ -6,14 +6,11 @@
//! interned Chalk types.
use rustc_middle::mir::interpret::ConstValue;
use rustc_middle::ty::fold::{TypeFoldable, TypeFolder, TypeVisitor};
use rustc_middle::ty::{self, AdtDef, Ty, TyCtxt};
use rustc_middle::ty::{self, AdtDef, TyCtxt};
use rustc_hir::def_id::DefId;
use rustc_target::spec::abi::Abi;
use smallvec::SmallVec;
use std::cmp::Ordering;
use std::fmt;
use std::hash::{Hash, Hasher};
@ -376,31 +373,10 @@ impl<'tcx> chalk_ir::interner::HasInterner for RustInterner<'tcx> {
type Interner = Self;
}
#[derive(Copy, Clone, PartialEq, Eq, Hash, Debug, HashStable, TypeFoldable)]
pub enum ChalkEnvironmentClause<'tcx> {
/// A normal rust `ty::Predicate` in the environment.
Predicate(ty::Predicate<'tcx>),
/// A special clause in the environment that gets lowered to
/// `chalk_ir::FromEnv::Ty`.
TypeFromEnv(Ty<'tcx>),
}
impl<'tcx> TypeFoldable<'tcx> for &'tcx ty::List<ChalkEnvironmentClause<'tcx>> {
fn super_fold_with<F: TypeFolder<'tcx>>(&self, folder: &mut F) -> Self {
let v = self.iter().map(|t| t.fold_with(folder)).collect::<SmallVec<[_; 8]>>();
folder.tcx().intern_chalk_environment_clause_list(&v)
}
fn super_visit_with<V: TypeVisitor<'tcx>>(&self, visitor: &mut V) -> bool {
self.iter().any(|t| t.visit_with(visitor))
}
}
/// We have to elaborate the environment of a chalk goal *before*
/// canonicalization. This type wraps the predicate and the elaborated
/// environment.
/// A chalk environment and goal.
#[derive(Copy, Clone, PartialEq, Eq, Hash, Debug, HashStable, TypeFoldable)]
pub struct ChalkEnvironmentAndGoal<'tcx> {
pub environment: &'tcx ty::List<ChalkEnvironmentClause<'tcx>>,
pub environment: &'tcx ty::List<ty::Predicate<'tcx>>,
pub goal: ty::Predicate<'tcx>,
}

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@ -26,14 +26,12 @@ use std::rc::Rc;
pub use self::select::{EvaluationCache, EvaluationResult, OverflowError, SelectionCache};
pub type ChalkCanonicalGoal<'tcx> = Canonical<'tcx, ChalkEnvironmentAndGoal<'tcx>>;
pub type CanonicalChalkEnvironmentAndGoal<'tcx> = Canonical<'tcx, ChalkEnvironmentAndGoal<'tcx>>;
pub use self::ImplSource::*;
pub use self::ObligationCauseCode::*;
pub use self::chalk::{
ChalkEnvironmentAndGoal, ChalkEnvironmentClause, RustInterner as ChalkRustInterner,
};
pub use self::chalk::{ChalkEnvironmentAndGoal, RustInterner as ChalkRustInterner};
/// Depending on the stage of compilation, we want projection to be
/// more or less conservative.

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@ -91,8 +91,6 @@ pub struct CtxtInterners<'tcx> {
projs: InternedSet<'tcx, List<ProjectionKind>>,
place_elems: InternedSet<'tcx, List<PlaceElem<'tcx>>>,
const_: InternedSet<'tcx, Const<'tcx>>,
chalk_environment_clause_list: InternedSet<'tcx, List<traits::ChalkEnvironmentClause<'tcx>>>,
}
impl<'tcx> CtxtInterners<'tcx> {
@ -110,7 +108,6 @@ impl<'tcx> CtxtInterners<'tcx> {
projs: Default::default(),
place_elems: Default::default(),
const_: Default::default(),
chalk_environment_clause_list: Default::default(),
}
}
@ -2041,7 +2038,7 @@ direct_interners! {
}
macro_rules! slice_interners {
($($field:ident: $method:ident($ty:ty)),+) => (
($($field:ident: $method:ident($ty:ty)),+ $(,)?) => (
$(impl<'tcx> TyCtxt<'tcx> {
pub fn $method(self, v: &[$ty]) -> &'tcx List<$ty> {
self.interners.$field.intern_ref(v, || {
@ -2060,8 +2057,6 @@ slice_interners!(
predicates: _intern_predicates(Predicate<'tcx>),
projs: _intern_projs(ProjectionKind),
place_elems: _intern_place_elems(PlaceElem<'tcx>),
chalk_environment_clause_list:
_intern_chalk_environment_clause_list(traits::ChalkEnvironmentClause<'tcx>)
);
impl<'tcx> TyCtxt<'tcx> {
@ -2460,13 +2455,6 @@ impl<'tcx> TyCtxt<'tcx> {
if ts.is_empty() { List::empty() } else { self._intern_canonical_var_infos(ts) }
}
pub fn intern_chalk_environment_clause_list(
self,
ts: &[traits::ChalkEnvironmentClause<'tcx>],
) -> &'tcx List<traits::ChalkEnvironmentClause<'tcx>> {
if ts.is_empty() { List::empty() } else { self._intern_chalk_environment_clause_list(ts) }
}
pub fn mk_fn_sig<I>(
self,
inputs: I,
@ -2524,18 +2512,6 @@ impl<'tcx> TyCtxt<'tcx> {
self.mk_substs(iter::once(self_ty.into()).chain(rest.iter().cloned()))
}
pub fn mk_chalk_environment_clause_list<
I: InternAs<
[traits::ChalkEnvironmentClause<'tcx>],
&'tcx List<traits::ChalkEnvironmentClause<'tcx>>,
>,
>(
self,
iter: I,
) -> I::Output {
iter.intern_with(|xs| self.intern_chalk_environment_clause_list(xs))
}
/// Walks upwards from `id` to find a node which might change lint levels with attributes.
/// It stops at `bound` and just returns it if reached.
pub fn maybe_lint_level_root_bounded(self, mut id: HirId, bound: HirId) -> HirId {

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@ -249,6 +249,9 @@ impl FlagComputation {
self.add_const(expected);
self.add_const(found);
}
ty::PredicateAtom::TypeWellFormedFromEnv(ty) => {
self.add_ty(ty);
}
}
}

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@ -1155,6 +1155,11 @@ pub enum PredicateAtom<'tcx> {
/// Constants must be equal. The first component is the const that is expected.
ConstEquate(&'tcx Const<'tcx>, &'tcx Const<'tcx>),
/// Represents a type found in the environment that we can use for implied bounds.
///
/// Only used for Chalk.
TypeWellFormedFromEnv(Ty<'tcx>),
}
impl<'tcx> PredicateAtom<'tcx> {
@ -1450,7 +1455,8 @@ impl<'tcx> Predicate<'tcx> {
| PredicateAtom::ClosureKind(..)
| PredicateAtom::TypeOutlives(..)
| PredicateAtom::ConstEvaluatable(..)
| PredicateAtom::ConstEquate(..) => None,
| PredicateAtom::ConstEquate(..)
| PredicateAtom::TypeWellFormedFromEnv(..) => None,
}
}
@ -1465,7 +1471,8 @@ impl<'tcx> Predicate<'tcx> {
| PredicateAtom::ObjectSafe(..)
| PredicateAtom::ClosureKind(..)
| PredicateAtom::ConstEvaluatable(..)
| PredicateAtom::ConstEquate(..) => None,
| PredicateAtom::ConstEquate(..)
| PredicateAtom::TypeWellFormedFromEnv(..) => None,
}
}
}
@ -1738,11 +1745,6 @@ pub struct ParamEnv<'tcx> {
///
/// Note: This is packed, use the reveal() method to access it.
packed: CopyTaggedPtr<&'tcx List<Predicate<'tcx>>, traits::Reveal, true>,
/// If this `ParamEnv` comes from a call to `tcx.param_env(def_id)`,
/// register that `def_id` (useful for transitioning to the chalk trait
/// solver).
pub def_id: Option<DefId>,
}
unsafe impl rustc_data_structures::tagged_ptr::Tag for traits::Reveal {
@ -1767,7 +1769,6 @@ impl<'tcx> fmt::Debug for ParamEnv<'tcx> {
f.debug_struct("ParamEnv")
.field("caller_bounds", &self.caller_bounds())
.field("reveal", &self.reveal())
.field("def_id", &self.def_id)
.finish()
}
}
@ -1776,23 +1777,16 @@ impl<'a, 'tcx> HashStable<StableHashingContext<'a>> for ParamEnv<'tcx> {
fn hash_stable(&self, hcx: &mut StableHashingContext<'a>, hasher: &mut StableHasher) {
self.caller_bounds().hash_stable(hcx, hasher);
self.reveal().hash_stable(hcx, hasher);
self.def_id.hash_stable(hcx, hasher);
}
}
impl<'tcx> TypeFoldable<'tcx> for ParamEnv<'tcx> {
fn super_fold_with<F: ty::fold::TypeFolder<'tcx>>(&self, folder: &mut F) -> Self {
ParamEnv::new(
self.caller_bounds().fold_with(folder),
self.reveal().fold_with(folder),
self.def_id.fold_with(folder),
)
ParamEnv::new(self.caller_bounds().fold_with(folder), self.reveal().fold_with(folder))
}
fn super_visit_with<V: TypeVisitor<'tcx>>(&self, visitor: &mut V) -> bool {
self.caller_bounds().visit_with(visitor)
|| self.reveal().visit_with(visitor)
|| self.def_id.visit_with(visitor)
self.caller_bounds().visit_with(visitor) || self.reveal().visit_with(visitor)
}
}
@ -1803,7 +1797,7 @@ impl<'tcx> ParamEnv<'tcx> {
/// type-checking.
#[inline]
pub fn empty() -> Self {
Self::new(List::empty(), Reveal::UserFacing, None)
Self::new(List::empty(), Reveal::UserFacing)
}
#[inline]
@ -1825,17 +1819,13 @@ impl<'tcx> ParamEnv<'tcx> {
/// or invoke `param_env.with_reveal_all()`.
#[inline]
pub fn reveal_all() -> Self {
Self::new(List::empty(), Reveal::All, None)
Self::new(List::empty(), Reveal::All)
}
/// Construct a trait environment with the given set of predicates.
#[inline]
pub fn new(
caller_bounds: &'tcx List<Predicate<'tcx>>,
reveal: Reveal,
def_id: Option<DefId>,
) -> Self {
ty::ParamEnv { packed: CopyTaggedPtr::new(caller_bounds, reveal), def_id }
pub fn new(caller_bounds: &'tcx List<Predicate<'tcx>>, reveal: Reveal) -> Self {
ty::ParamEnv { packed: CopyTaggedPtr::new(caller_bounds, reveal) }
}
pub fn with_user_facing(mut self) -> Self {
@ -1857,12 +1847,12 @@ impl<'tcx> ParamEnv<'tcx> {
return self;
}
ParamEnv::new(tcx.normalize_opaque_types(self.caller_bounds()), Reveal::All, self.def_id)
ParamEnv::new(tcx.normalize_opaque_types(self.caller_bounds()), Reveal::All)
}
/// Returns this same environment but with no caller bounds.
pub fn without_caller_bounds(self) -> Self {
Self::new(List::empty(), self.reveal(), self.def_id)
Self::new(List::empty(), self.reveal())
}
/// Creates a suitable environment in which to perform trait

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@ -2096,6 +2096,11 @@ define_print_and_forward_display! {
print(c2),
write("`"))
}
ty::PredicateAtom::TypeWellFormedFromEnv(ty) => {
p!(write("the type `"),
print(ty),
write("` is found in the environment"))
}
}
}

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@ -260,6 +260,9 @@ impl fmt::Debug for ty::PredicateAtom<'tcx> {
write!(f, "ConstEvaluatable({:?}, {:?})", def_id, substs)
}
ty::PredicateAtom::ConstEquate(c1, c2) => write!(f, "ConstEquate({:?}, {:?})", c1, c2),
ty::PredicateAtom::TypeWellFormedFromEnv(ty) => {
write!(f, "TypeWellFormedFromEnv({:?})", ty)
}
}
}
}
@ -536,6 +539,9 @@ impl<'a, 'tcx> Lift<'tcx> for ty::PredicateAtom<'a> {
ty::PredicateAtom::ConstEquate(c1, c2) => {
tcx.lift(&(c1, c2)).map(|(c1, c2)| ty::PredicateAtom::ConstEquate(c1, c2))
}
ty::PredicateAtom::TypeWellFormedFromEnv(ty) => {
tcx.lift(&ty).map(ty::PredicateAtom::TypeWellFormedFromEnv)
}
}
}
}
@ -551,7 +557,7 @@ impl<'a, 'tcx> Lift<'tcx> for ty::ParamEnv<'a> {
type Lifted = ty::ParamEnv<'tcx>;
fn lift_to_tcx(&self, tcx: TyCtxt<'tcx>) -> Option<Self::Lifted> {
tcx.lift(&self.caller_bounds())
.map(|caller_bounds| ty::ParamEnv::new(caller_bounds, self.reveal(), self.def_id))
.map(|caller_bounds| ty::ParamEnv::new(caller_bounds, self.reveal()))
}
}

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@ -30,7 +30,8 @@ pub fn is_min_const_fn(tcx: TyCtxt<'tcx>, def_id: DefId, body: &'a Body<'tcx>) -
| ty::PredicateAtom::WellFormed(_)
| ty::PredicateAtom::Projection(_)
| ty::PredicateAtom::ConstEvaluatable(..)
| ty::PredicateAtom::ConstEquate(..) => continue,
| ty::PredicateAtom::ConstEquate(..)
| ty::PredicateAtom::TypeWellFormedFromEnv(..) => continue,
ty::PredicateAtom::ObjectSafe(_) => {
bug!("object safe predicate on function: {:#?}", predicate)
}

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@ -1261,7 +1261,8 @@ crate fn required_region_bounds(
| ty::PredicateAtom::ClosureKind(..)
| ty::PredicateAtom::RegionOutlives(..)
| ty::PredicateAtom::ConstEvaluatable(..)
| ty::PredicateAtom::ConstEquate(..) => None,
| ty::PredicateAtom::ConstEquate(..)
| ty::PredicateAtom::TypeWellFormedFromEnv(..) => None,
ty::PredicateAtom::TypeOutlives(ty::OutlivesPredicate(ref t, ref r)) => {
// Search for a bound of the form `erased_self_ty
// : 'a`, but be wary of something like `for<'a>

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@ -373,14 +373,12 @@ impl AutoTraitFinder<'tcx> {
computed_preds.clone().chain(user_computed_preds.iter().cloned()),
)
.map(|o| o.predicate);
new_env =
ty::ParamEnv::new(tcx.mk_predicates(normalized_preds), param_env.reveal(), None);
new_env = ty::ParamEnv::new(tcx.mk_predicates(normalized_preds), param_env.reveal());
}
let final_user_env = ty::ParamEnv::new(
tcx.mk_predicates(user_computed_preds.into_iter()),
user_env.reveal(),
None,
);
debug!(
"evaluate_nested_obligations(ty={:?}, trait_did={:?}): succeeded with '{:?}' \

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@ -4,12 +4,11 @@ use crate::infer::canonical::OriginalQueryValues;
use crate::infer::InferCtxt;
use crate::traits::query::NoSolution;
use crate::traits::{
ChalkEnvironmentAndGoal, ChalkEnvironmentClause, FulfillmentError, FulfillmentErrorCode,
ObligationCause, PredicateObligation, SelectionError, TraitEngine,
ChalkEnvironmentAndGoal, FulfillmentError, FulfillmentErrorCode, ObligationCause,
PredicateObligation, SelectionError, TraitEngine,
};
use rustc_data_structures::fx::FxIndexSet;
use rustc_hir::def_id::DefId;
use rustc_middle::ty::{self, Ty, TyCtxt};
use rustc_middle::ty::{self, Ty};
pub struct FulfillmentContext<'tcx> {
obligations: FxIndexSet<PredicateObligation<'tcx>>,
@ -21,132 +20,6 @@ impl FulfillmentContext<'tcx> {
}
}
fn environment<'tcx>(
tcx: TyCtxt<'tcx>,
def_id: DefId,
) -> &'tcx ty::List<ChalkEnvironmentClause<'tcx>> {
use rustc_hir::{ForeignItemKind, ImplItemKind, ItemKind, Node, TraitItemKind};
use rustc_middle::ty::subst::GenericArgKind;
debug!("environment(def_id = {:?})", def_id);
// The environment of an impl Trait type is its defining function's environment.
if let Some(parent) = ty::is_impl_trait_defn(tcx, def_id) {
return environment(tcx, parent);
}
// Compute the bounds on `Self` and the type parameters.
let ty::InstantiatedPredicates { predicates, .. } =
tcx.predicates_of(def_id).instantiate_identity(tcx);
let clauses = predicates.into_iter().map(ChalkEnvironmentClause::Predicate);
let hir_id = tcx.hir().local_def_id_to_hir_id(def_id.expect_local());
let node = tcx.hir().get(hir_id);
enum NodeKind {
TraitImpl,
InherentImpl,
Fn,
Other,
};
let node_kind = match node {
Node::TraitItem(item) => match item.kind {
TraitItemKind::Fn(..) => NodeKind::Fn,
_ => NodeKind::Other,
},
Node::ImplItem(item) => match item.kind {
ImplItemKind::Fn(..) => NodeKind::Fn,
_ => NodeKind::Other,
},
Node::Item(item) => match item.kind {
ItemKind::Impl { of_trait: Some(_), .. } => NodeKind::TraitImpl,
ItemKind::Impl { of_trait: None, .. } => NodeKind::InherentImpl,
ItemKind::Fn(..) => NodeKind::Fn,
_ => NodeKind::Other,
},
Node::ForeignItem(item) => match item.kind {
ForeignItemKind::Fn(..) => NodeKind::Fn,
_ => NodeKind::Other,
},
// FIXME: closures?
_ => NodeKind::Other,
};
// FIXME(eddyb) isn't the unordered nature of this a hazard?
let mut inputs = FxIndexSet::default();
match node_kind {
// In a trait impl, we assume that the header trait ref and all its
// constituents are well-formed.
NodeKind::TraitImpl => {
let trait_ref = tcx.impl_trait_ref(def_id).expect("not an impl");
// FIXME(chalk): this has problems because of late-bound regions
//inputs.extend(trait_ref.substs.iter().flat_map(|arg| arg.walk()));
inputs.extend(trait_ref.substs.iter());
}
// In an inherent impl, we assume that the receiver type and all its
// constituents are well-formed.
NodeKind::InherentImpl => {
let self_ty = tcx.type_of(def_id);
inputs.extend(self_ty.walk());
}
// In an fn, we assume that the arguments and all their constituents are
// well-formed.
NodeKind::Fn => {
let fn_sig = tcx.fn_sig(def_id);
let fn_sig = tcx.liberate_late_bound_regions(def_id, &fn_sig);
inputs.extend(fn_sig.inputs().iter().flat_map(|ty| ty.walk()));
}
NodeKind::Other => (),
}
let input_clauses = inputs.into_iter().filter_map(|arg| {
match arg.unpack() {
GenericArgKind::Type(ty) => Some(ChalkEnvironmentClause::TypeFromEnv(ty)),
// FIXME(eddyb) no WF conditions from lifetimes?
GenericArgKind::Lifetime(_) => None,
// FIXME(eddyb) support const generics in Chalk
GenericArgKind::Const(_) => None,
}
});
tcx.mk_chalk_environment_clause_list(clauses.chain(input_clauses))
}
/// We need to wrap a `ty::Predicate` in an elaborated environment *before* we
/// canonicalize. This is due to the fact that we insert extra clauses into the
/// environment for all input types (`FromEnv`).
fn in_environment(
infcx: &InferCtxt<'_, 'tcx>,
obligation: &PredicateObligation<'tcx>,
) -> ChalkEnvironmentAndGoal<'tcx> {
assert!(!infcx.is_in_snapshot());
let obligation = infcx.resolve_vars_if_possible(obligation);
let environment = match obligation.param_env.def_id {
Some(def_id) => environment(infcx.tcx, def_id),
None if obligation.param_env.caller_bounds().is_empty() => ty::List::empty(),
// FIXME(chalk): this is hit in ui/where-clauses/where-clause-constraints-are-local-for-trait-impl
// and ui/generics/generic-static-methods
//_ => bug!("non-empty `ParamEnv` with no def-id"),
_ => ty::List::empty(),
};
ChalkEnvironmentAndGoal { environment, goal: obligation.predicate }
}
impl TraitEngine<'tcx> for FulfillmentContext<'tcx> {
fn normalize_projection_type(
&mut self,
@ -195,6 +68,8 @@ impl TraitEngine<'tcx> for FulfillmentContext<'tcx> {
&mut self,
infcx: &InferCtxt<'_, 'tcx>,
) -> Result<(), Vec<FulfillmentError<'tcx>>> {
assert!(!infcx.is_in_snapshot());
let mut errors = Vec::new();
let mut next_round = FxIndexSet::default();
let mut making_progress;
@ -205,10 +80,11 @@ impl TraitEngine<'tcx> for FulfillmentContext<'tcx> {
// We iterate over all obligations, and record if we are able
// to unambiguously prove at least one obligation.
for obligation in self.obligations.drain(..) {
let goal_in_environment = in_environment(infcx, &obligation);
let obligation = infcx.resolve_vars_if_possible(&obligation);
let environment = obligation.param_env.caller_bounds();
let goal = ChalkEnvironmentAndGoal { environment, goal: obligation.predicate };
let mut orig_values = OriginalQueryValues::default();
let canonical_goal =
infcx.canonicalize_query(&goal_in_environment, &mut orig_values);
let canonical_goal = infcx.canonicalize_query(&goal, &mut orig_values);
match infcx.tcx.evaluate_goal(canonical_goal) {
Ok(response) => {

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@ -663,6 +663,11 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> {
obligation
)
}
ty::PredicateAtom::TypeWellFormedFromEnv(..) => span_bug!(
span,
"TypeWellFormedFromEnv predicate should only exist in the environment"
),
}
}

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@ -87,7 +87,7 @@ pub struct PendingPredicateObligation<'tcx> {
// `PendingPredicateObligation` is used a lot. Make sure it doesn't unintentionally get bigger.
#[cfg(target_arch = "x86_64")]
static_assert_size!(PendingPredicateObligation<'_>, 64);
static_assert_size!(PendingPredicateObligation<'_>, 56);
impl<'a, 'tcx> FulfillmentContext<'tcx> {
/// Creates a new fulfillment context.
@ -355,6 +355,9 @@ impl<'a, 'b, 'tcx> ObligationProcessor for FulfillProcessor<'a, 'b, 'tcx> {
obligation.with(pred.to_predicate(self.selcx.tcx())),
]))
}
ty::PredicateAtom::TypeWellFormedFromEnv(..) => {
bug!("TypeWellFormedFromEnv is only used for Chalk")
}
},
&ty::PredicateKind::Atom(atom) => match atom {
ty::PredicateAtom::Trait(ref data, _) => {
@ -536,6 +539,9 @@ impl<'a, 'b, 'tcx> ObligationProcessor for FulfillProcessor<'a, 'b, 'tcx> {
}
}
}
ty::PredicateAtom::TypeWellFormedFromEnv(..) => {
bug!("TypeWellFormedFromEnv is only used for Chalk")
}
},
}
}

View File

@ -302,11 +302,8 @@ pub fn normalize_param_env_or_error<'tcx>(
debug!("normalize_param_env_or_error: elaborated-predicates={:?}", predicates);
let elaborated_env = ty::ParamEnv::new(
tcx.intern_predicates(&predicates),
unnormalized_env.reveal(),
unnormalized_env.def_id,
);
let elaborated_env =
ty::ParamEnv::new(tcx.intern_predicates(&predicates), unnormalized_env.reveal());
// HACK: we are trying to normalize the param-env inside *itself*. The problem is that
// normalization expects its param-env to be already normalized, which means we have
@ -360,7 +357,7 @@ pub fn normalize_param_env_or_error<'tcx>(
let outlives_env: Vec<_> =
non_outlives_predicates.iter().chain(&outlives_predicates).cloned().collect();
let outlives_env =
ty::ParamEnv::new(tcx.intern_predicates(&outlives_env), unnormalized_env.reveal(), None);
ty::ParamEnv::new(tcx.intern_predicates(&outlives_env), unnormalized_env.reveal());
let outlives_predicates = match do_normalize_predicates(
tcx,
region_context,
@ -380,11 +377,7 @@ pub fn normalize_param_env_or_error<'tcx>(
let mut predicates = non_outlives_predicates;
predicates.extend(outlives_predicates);
debug!("normalize_param_env_or_error: final predicates={:?}", predicates);
ty::ParamEnv::new(
tcx.intern_predicates(&predicates),
unnormalized_env.reveal(),
unnormalized_env.def_id,
)
ty::ParamEnv::new(tcx.intern_predicates(&predicates), unnormalized_env.reveal())
}
pub fn fully_normalize<'a, 'tcx, T>(

View File

@ -276,7 +276,8 @@ fn predicates_reference_self(
| ty::PredicateAtom::ClosureKind(..)
| ty::PredicateAtom::Subtype(..)
| ty::PredicateAtom::ConstEvaluatable(..)
| ty::PredicateAtom::ConstEquate(..) => None,
| ty::PredicateAtom::ConstEquate(..)
| ty::PredicateAtom::TypeWellFormedFromEnv(..) => None,
}
})
.collect()
@ -310,7 +311,8 @@ fn generics_require_sized_self(tcx: TyCtxt<'_>, def_id: DefId) -> bool {
| ty::PredicateAtom::ClosureKind(..)
| ty::PredicateAtom::TypeOutlives(..)
| ty::PredicateAtom::ConstEvaluatable(..)
| ty::PredicateAtom::ConstEquate(..) => false,
| ty::PredicateAtom::ConstEquate(..)
| ty::PredicateAtom::TypeWellFormedFromEnv(..) => false,
}
})
}
@ -654,11 +656,7 @@ fn receiver_is_dispatchable<'tcx>(
.chain(iter::once(trait_predicate))
.collect();
ty::ParamEnv::new(
tcx.intern_predicates(&caller_bounds),
param_env.reveal(),
param_env.def_id,
)
ty::ParamEnv::new(tcx.intern_predicates(&caller_bounds), param_env.reveal())
};
// Receiver: DispatchFromDyn<Receiver[Self => U]>

View File

@ -593,6 +593,9 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
}
}
}
ty::PredicateAtom::TypeWellFormedFromEnv(..) => {
bug!("TypeWellFormedFromEnv is only used for chalk")
}
}
}

View File

@ -127,6 +127,9 @@ pub fn predicate_obligations<'a, 'tcx>(
wf.compute(c1.into());
wf.compute(c2.into());
}
ty::PredicateAtom::TypeWellFormedFromEnv(..) => {
bug!("TypeWellFormedFromEnv is only used for Chalk")
}
}
wf.normalize()

View File

@ -31,9 +31,7 @@
//! not. To lower anything wrapped in a `Binder`, we first deeply find any bound
//! variables from the current `Binder`.
use rustc_middle::traits::{
ChalkEnvironmentAndGoal, ChalkEnvironmentClause, ChalkRustInterner as RustInterner,
};
use rustc_middle::traits::{ChalkEnvironmentAndGoal, ChalkRustInterner as RustInterner};
use rustc_middle::ty::fold::TypeFolder;
use rustc_middle::ty::subst::{GenericArg, GenericArgKind, SubstsRef};
use rustc_middle::ty::{
@ -43,8 +41,6 @@ use rustc_span::def_id::DefId;
use std::collections::btree_map::{BTreeMap, Entry};
use chalk_ir::fold::shift::Shift;
/// Essentially an `Into` with a `&RustInterner` parameter
crate trait LowerInto<'tcx, T> {
/// Lower a rustc construct (e.g., `ty::TraitPredicate`) to a chalk type, consuming `self`.
@ -82,60 +78,45 @@ impl<'tcx> LowerInto<'tcx, chalk_ir::InEnvironment<chalk_ir::Goal<RustInterner<'
self,
interner: &RustInterner<'tcx>,
) -> chalk_ir::InEnvironment<chalk_ir::Goal<RustInterner<'tcx>>> {
let clauses = self.environment.into_iter().map(|clause| match clause {
ChalkEnvironmentClause::Predicate(predicate) => {
let (predicate, binders, _named_regions) =
collect_bound_vars(interner, interner.tcx, &predicate.bound_atom(interner.tcx));
let consequence = match predicate {
ty::PredicateAtom::Trait(predicate, _) => chalk_ir::DomainGoal::FromEnv(
chalk_ir::FromEnv::Trait(predicate.trait_ref.lower_into(interner)),
),
ty::PredicateAtom::RegionOutlives(predicate) => chalk_ir::DomainGoal::Holds(
chalk_ir::WhereClause::LifetimeOutlives(chalk_ir::LifetimeOutlives {
a: predicate.0.lower_into(interner),
b: predicate.1.lower_into(interner),
}),
),
ty::PredicateAtom::TypeOutlives(predicate) => chalk_ir::DomainGoal::Holds(
chalk_ir::WhereClause::TypeOutlives(chalk_ir::TypeOutlives {
ty: predicate.0.lower_into(interner),
lifetime: predicate.1.lower_into(interner),
}),
),
ty::PredicateAtom::Projection(predicate) => chalk_ir::DomainGoal::Holds(
chalk_ir::WhereClause::AliasEq(predicate.lower_into(interner)),
),
ty::PredicateAtom::WellFormed(..)
| ty::PredicateAtom::ObjectSafe(..)
| ty::PredicateAtom::ClosureKind(..)
| ty::PredicateAtom::Subtype(..)
| ty::PredicateAtom::ConstEvaluatable(..)
| ty::PredicateAtom::ConstEquate(..) => {
bug!("unexpected predicate {}", predicate)
}
};
let value = chalk_ir::ProgramClauseImplication {
consequence,
conditions: chalk_ir::Goals::empty(interner),
priority: chalk_ir::ClausePriority::High,
constraints: chalk_ir::Constraints::empty(interner),
};
chalk_ir::ProgramClauseData(chalk_ir::Binders::new(binders, value)).intern(interner)
}
ChalkEnvironmentClause::TypeFromEnv(ty) => {
chalk_ir::ProgramClauseData(chalk_ir::Binders::new(
chalk_ir::VariableKinds::empty(interner),
chalk_ir::ProgramClauseImplication {
consequence: chalk_ir::DomainGoal::FromEnv(chalk_ir::FromEnv::Ty(
ty.lower_into(interner).shifted_in(interner),
)),
conditions: chalk_ir::Goals::empty(interner),
priority: chalk_ir::ClausePriority::High,
constraints: chalk_ir::Constraints::empty(interner),
},
))
.intern(interner)
}
let clauses = self.environment.into_iter().map(|predicate| {
let (predicate, binders, _named_regions) =
collect_bound_vars(interner, interner.tcx, &predicate.bound_atom(interner.tcx));
let consequence = match predicate {
ty::PredicateAtom::TypeWellFormedFromEnv(ty) => {
chalk_ir::DomainGoal::FromEnv(chalk_ir::FromEnv::Ty(ty.lower_into(interner)))
}
ty::PredicateAtom::Trait(predicate, _) => chalk_ir::DomainGoal::FromEnv(
chalk_ir::FromEnv::Trait(predicate.trait_ref.lower_into(interner)),
),
ty::PredicateAtom::RegionOutlives(predicate) => chalk_ir::DomainGoal::Holds(
chalk_ir::WhereClause::LifetimeOutlives(chalk_ir::LifetimeOutlives {
a: predicate.0.lower_into(interner),
b: predicate.1.lower_into(interner),
}),
),
ty::PredicateAtom::TypeOutlives(predicate) => chalk_ir::DomainGoal::Holds(
chalk_ir::WhereClause::TypeOutlives(chalk_ir::TypeOutlives {
ty: predicate.0.lower_into(interner),
lifetime: predicate.1.lower_into(interner),
}),
),
ty::PredicateAtom::Projection(predicate) => chalk_ir::DomainGoal::Holds(
chalk_ir::WhereClause::AliasEq(predicate.lower_into(interner)),
),
ty::PredicateAtom::WellFormed(..)
| ty::PredicateAtom::ObjectSafe(..)
| ty::PredicateAtom::ClosureKind(..)
| ty::PredicateAtom::Subtype(..)
| ty::PredicateAtom::ConstEvaluatable(..)
| ty::PredicateAtom::ConstEquate(..) => bug!("unexpected predicate {}", predicate),
};
let value = chalk_ir::ProgramClauseImplication {
consequence,
conditions: chalk_ir::Goals::empty(interner),
priority: chalk_ir::ClausePriority::High,
constraints: chalk_ir::Constraints::empty(interner),
};
chalk_ir::ProgramClauseData(chalk_ir::Binders::new(binders, value)).intern(interner)
});
let goal: chalk_ir::GoalData<RustInterner<'tcx>> = self.goal.lower_into(&interner);
@ -214,6 +195,9 @@ impl<'tcx> LowerInto<'tcx, chalk_ir::GoalData<RustInterner<'tcx>>> for ty::Predi
| ty::PredicateAtom::ConstEquate(..) => {
chalk_ir::GoalData::All(chalk_ir::Goals::empty(interner))
}
ty::PredicateAtom::TypeWellFormedFromEnv(ty) => chalk_ir::GoalData::DomainGoal(
chalk_ir::DomainGoal::FromEnv(chalk_ir::FromEnv::Ty(ty.lower_into(interner))),
),
};
chalk_ir::GoalData::Quantified(
@ -684,7 +668,10 @@ impl<'tcx> LowerInto<'tcx, Option<chalk_ir::QuantifiedWhereClause<RustInterner<'
| ty::PredicateAtom::ClosureKind(..)
| ty::PredicateAtom::Subtype(..)
| ty::PredicateAtom::ConstEvaluatable(..)
| ty::PredicateAtom::ConstEquate(..) => bug!("unexpected predicate {}", &self),
| ty::PredicateAtom::ConstEquate(..)
| ty::PredicateAtom::TypeWellFormedFromEnv(..) => {
bug!("unexpected predicate {}", &self)
}
};
value.map(|value| chalk_ir::Binders::new(binders, value))
}

View File

@ -1,8 +1,7 @@
//! Calls `chalk-solve` to solve a `ty::Predicate`
//!
//! In order to call `chalk-solve`, this file must convert a
//! `ChalkCanonicalGoal` into a Chalk ucanonical goal. It then calls Chalk, and
//! converts the answer back into rustc solution.
//! In order to call `chalk-solve`, this file must convert a `CanonicalChalkEnvironmentAndGoal` into
//! a Chalk uncanonical goal. It then calls Chalk, and converts the answer back into rustc solution.
crate mod db;
crate mod lowering;
@ -20,7 +19,7 @@ use rustc_middle::ty::{self, BoundVar, ParamTy, TyCtxt, TypeFoldable};
use rustc_infer::infer::canonical::{
Canonical, CanonicalVarValues, Certainty, QueryRegionConstraints, QueryResponse,
};
use rustc_infer::traits::{self, ChalkCanonicalGoal};
use rustc_infer::traits::{self, CanonicalChalkEnvironmentAndGoal};
use crate::chalk::db::RustIrDatabase as ChalkRustIrDatabase;
use crate::chalk::lowering::{
@ -35,7 +34,7 @@ crate fn provide(p: &mut Providers) {
crate fn evaluate_goal<'tcx>(
tcx: TyCtxt<'tcx>,
obligation: ChalkCanonicalGoal<'tcx>,
obligation: CanonicalChalkEnvironmentAndGoal<'tcx>,
) -> Result<&'tcx Canonical<'tcx, QueryResponse<'tcx, ()>>, traits::query::NoSolution> {
let interner = ChalkRustInterner { tcx };

View File

@ -103,7 +103,8 @@ fn compute_implied_outlives_bounds<'tcx>(
| ty::PredicateAtom::ClosureKind(..)
| ty::PredicateAtom::ObjectSafe(..)
| ty::PredicateAtom::ConstEvaluatable(..)
| ty::PredicateAtom::ConstEquate(..) => vec![],
| ty::PredicateAtom::ConstEquate(..)
| ty::PredicateAtom::TypeWellFormedFromEnv(..) => vec![],
ty::PredicateAtom::WellFormed(arg) => {
wf_args.push(arg);
vec![]

View File

@ -49,6 +49,7 @@ fn not_outlives_predicate(p: &ty::Predicate<'tcx>) -> bool {
| ty::PredicateAtom::ClosureKind(..)
| ty::PredicateAtom::Subtype(..)
| ty::PredicateAtom::ConstEvaluatable(..)
| ty::PredicateAtom::ConstEquate(..) => true,
| ty::PredicateAtom::ConstEquate(..)
| ty::PredicateAtom::TypeWellFormedFromEnv(..) => true,
}
}

View File

@ -1,3 +1,4 @@
use rustc_data_structures::fx::FxIndexSet;
use rustc_data_structures::svh::Svh;
use rustc_hir as hir;
use rustc_hir::def::DefKind;
@ -5,7 +6,9 @@ use rustc_hir::def_id::{CrateNum, DefId, LocalDefId, LOCAL_CRATE};
use rustc_infer::traits::util;
use rustc_middle::hir::map as hir_map;
use rustc_middle::ty::subst::{InternalSubsts, Subst};
use rustc_middle::ty::{self, ToPredicate, Ty, TyCtxt, WithConstness};
use rustc_middle::ty::{
self, Binder, Predicate, PredicateAtom, PredicateKind, ToPredicate, Ty, TyCtxt, WithConstness,
};
use rustc_session::CrateDisambiguator;
use rustc_span::symbol::Symbol;
use rustc_span::Span;
@ -245,7 +248,7 @@ fn param_env(tcx: TyCtxt<'_>, def_id: DefId) -> ty::ParamEnv<'_> {
}
// Compute the bounds on Self and the type parameters.
let ty::InstantiatedPredicates { predicates, .. } =
let ty::InstantiatedPredicates { mut predicates, .. } =
tcx.predicates_of(def_id).instantiate_identity(tcx);
// Finally, we have to normalize the bounds in the environment, in
@ -260,11 +263,13 @@ fn param_env(tcx: TyCtxt<'_>, def_id: DefId) -> ty::ParamEnv<'_> {
// are any errors at that point, so after type checking you can be
// sure that this will succeed without errors anyway.
let unnormalized_env = ty::ParamEnv::new(
tcx.intern_predicates(&predicates),
traits::Reveal::UserFacing,
tcx.sess.opts.debugging_opts.chalk.then_some(def_id),
);
if tcx.sess.opts.debugging_opts.chalk {
let environment = well_formed_types_in_env(tcx, def_id);
predicates.extend(environment);
}
let unnormalized_env =
ty::ParamEnv::new(tcx.intern_predicates(&predicates), traits::Reveal::UserFacing);
let body_id = def_id
.as_local()
@ -276,6 +281,122 @@ fn param_env(tcx: TyCtxt<'_>, def_id: DefId) -> ty::ParamEnv<'_> {
traits::normalize_param_env_or_error(tcx, def_id, unnormalized_env, cause)
}
/// Elaborate the environment.
///
/// Collect a list of `Predicate`'s used for building the `ParamEnv`. Adds `TypeWellFormedFromEnv`'s
/// that are assumed to be well-formed (because they come from the environment).
///
/// Used only in chalk mode.
fn well_formed_types_in_env<'tcx>(
tcx: TyCtxt<'tcx>,
def_id: DefId,
) -> &'tcx ty::List<Predicate<'tcx>> {
use rustc_hir::{ForeignItemKind, ImplItemKind, ItemKind, Node, TraitItemKind};
use rustc_middle::ty::subst::GenericArgKind;
debug!("environment(def_id = {:?})", def_id);
// The environment of an impl Trait type is its defining function's environment.
if let Some(parent) = ty::is_impl_trait_defn(tcx, def_id) {
return well_formed_types_in_env(tcx, parent);
}
// Compute the bounds on `Self` and the type parameters.
let ty::InstantiatedPredicates { predicates, .. } =
tcx.predicates_of(def_id).instantiate_identity(tcx);
let clauses = predicates.into_iter();
if !def_id.is_local() {
return ty::List::empty();
}
let hir_id = tcx.hir().local_def_id_to_hir_id(def_id.expect_local());
let node = tcx.hir().get(hir_id);
enum NodeKind {
TraitImpl,
InherentImpl,
Fn,
Other,
};
let node_kind = match node {
Node::TraitItem(item) => match item.kind {
TraitItemKind::Fn(..) => NodeKind::Fn,
_ => NodeKind::Other,
},
Node::ImplItem(item) => match item.kind {
ImplItemKind::Fn(..) => NodeKind::Fn,
_ => NodeKind::Other,
},
Node::Item(item) => match item.kind {
ItemKind::Impl { of_trait: Some(_), .. } => NodeKind::TraitImpl,
ItemKind::Impl { of_trait: None, .. } => NodeKind::InherentImpl,
ItemKind::Fn(..) => NodeKind::Fn,
_ => NodeKind::Other,
},
Node::ForeignItem(item) => match item.kind {
ForeignItemKind::Fn(..) => NodeKind::Fn,
_ => NodeKind::Other,
},
// FIXME: closures?
_ => NodeKind::Other,
};
// FIXME(eddyb) isn't the unordered nature of this a hazard?
let mut inputs = FxIndexSet::default();
match node_kind {
// In a trait impl, we assume that the header trait ref and all its
// constituents are well-formed.
NodeKind::TraitImpl => {
let trait_ref = tcx.impl_trait_ref(def_id).expect("not an impl");
// FIXME(chalk): this has problems because of late-bound regions
//inputs.extend(trait_ref.substs.iter().flat_map(|arg| arg.walk()));
inputs.extend(trait_ref.substs.iter());
}
// In an inherent impl, we assume that the receiver type and all its
// constituents are well-formed.
NodeKind::InherentImpl => {
let self_ty = tcx.type_of(def_id);
inputs.extend(self_ty.walk());
}
// In an fn, we assume that the arguments and all their constituents are
// well-formed.
NodeKind::Fn => {
let fn_sig = tcx.fn_sig(def_id);
let fn_sig = tcx.liberate_late_bound_regions(def_id, &fn_sig);
inputs.extend(fn_sig.inputs().iter().flat_map(|ty| ty.walk()));
}
NodeKind::Other => (),
}
let input_clauses = inputs.into_iter().filter_map(|arg| {
match arg.unpack() {
GenericArgKind::Type(ty) => {
let binder = Binder::dummy(PredicateAtom::TypeWellFormedFromEnv(ty));
Some(tcx.mk_predicate(PredicateKind::ForAll(binder)))
}
// FIXME(eddyb) no WF conditions from lifetimes?
GenericArgKind::Lifetime(_) => None,
// FIXME(eddyb) support const generics in Chalk
GenericArgKind::Const(_) => None,
}
});
tcx.mk_predicates(clauses.chain(input_clauses))
}
fn param_env_reveal_all_normalized(tcx: TyCtxt<'_>, def_id: DefId) -> ty::ParamEnv<'_> {
tcx.param_env(def_id).with_reveal_all_normalized(tcx)
}

View File

@ -202,11 +202,8 @@ fn compare_predicate_entailment<'tcx>(
// The key step here is to update the caller_bounds's predicates to be
// the new hybrid bounds we computed.
let normalize_cause = traits::ObligationCause::misc(impl_m_span, impl_m_hir_id);
let param_env = ty::ParamEnv::new(
tcx.intern_predicates(&hybrid_preds.predicates),
Reveal::UserFacing,
None,
);
let param_env =
ty::ParamEnv::new(tcx.intern_predicates(&hybrid_preds.predicates), Reveal::UserFacing);
let param_env = traits::normalize_param_env_or_error(
tcx,
impl_m.def_id,
@ -1120,11 +1117,8 @@ fn compare_type_predicate_entailment<'tcx>(
debug!("compare_type_predicate_entailment: bounds={:?}", hybrid_preds);
let normalize_cause = traits::ObligationCause::misc(impl_ty_span, impl_ty_hir_id);
let param_env = ty::ParamEnv::new(
tcx.intern_predicates(&hybrid_preds.predicates),
Reveal::UserFacing,
None,
);
let param_env =
ty::ParamEnv::new(tcx.intern_predicates(&hybrid_preds.predicates), Reveal::UserFacing);
let param_env = traits::normalize_param_env_or_error(
tcx,
impl_ty.def_id,
@ -1227,7 +1221,7 @@ fn compare_projection_bounds<'tcx>(
})
.to_predicate(tcx),
);
ty::ParamEnv::new(tcx.intern_predicates(&predicates), Reveal::UserFacing, None)
ty::ParamEnv::new(tcx.intern_predicates(&predicates), Reveal::UserFacing)
};
tcx.infer_ctxt().enter(move |infcx| {

View File

@ -814,7 +814,8 @@ impl<'a, 'tcx> ProbeContext<'a, 'tcx> {
| ty::PredicateAtom::ClosureKind(..)
| ty::PredicateAtom::TypeOutlives(..)
| ty::PredicateAtom::ConstEvaluatable(..)
| ty::PredicateAtom::ConstEquate(..) => None,
| ty::PredicateAtom::ConstEquate(..)
| ty::PredicateAtom::TypeWellFormedFromEnv(..) => None,
},
);

View File

@ -3918,6 +3918,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
// code is looking for a self type of a unresolved
// inference variable.
ty::PredicateAtom::ClosureKind(..) => None,
ty::PredicateAtom::TypeWellFormedFromEnv(..) => None,
}
})
.filter(move |(tr, _)| self.self_type_matches_expected_vid(*tr, ty_var_root))

View File

@ -405,6 +405,7 @@ fn trait_predicate_kind<'tcx>(
| ty::PredicateAtom::ObjectSafe(_)
| ty::PredicateAtom::ClosureKind(..)
| ty::PredicateAtom::ConstEvaluatable(..)
| ty::PredicateAtom::ConstEquate(..) => None,
| ty::PredicateAtom::ConstEquate(..)
| ty::PredicateAtom::TypeWellFormedFromEnv(..) => None,
}
}

View File

@ -57,7 +57,8 @@ impl<'tcx> ExplicitPredicatesMap<'tcx> {
| ty::PredicateAtom::ClosureKind(..)
| ty::PredicateAtom::Subtype(..)
| ty::PredicateAtom::ConstEvaluatable(..)
| ty::PredicateAtom::ConstEquate(..) => (),
| ty::PredicateAtom::ConstEquate(..)
| ty::PredicateAtom::TypeWellFormedFromEnv(..) => (),
}
}

View File

@ -508,7 +508,8 @@ impl<'a> Clean<Option<WherePredicate>> for ty::Predicate<'a> {
| ty::PredicateAtom::ObjectSafe(..)
| ty::PredicateAtom::ClosureKind(..)
| ty::PredicateAtom::ConstEvaluatable(..)
| ty::PredicateAtom::ConstEquate(..) => panic!("not user writable"),
| ty::PredicateAtom::ConstEquate(..)
| ty::PredicateAtom::TypeWellFormedFromEnv(..) => panic!("not user writable"),
}
}
}

View File

@ -1,11 +1,11 @@
error[E0277]: the trait bound `{float}: Bar` is not satisfied
--> $DIR/type_inference.rs:27:5
--> $DIR/type_inference.rs:27:14
|
LL | fn only_bar<T: Bar>(_x: T) { }
| --- required by this bound in `only_bar`
...
LL | only_bar(x);
| ^^^^^^^^ the trait `Bar` is not implemented for `{float}`
| ^ the trait `Bar` is not implemented for `{float}`
|
= help: the following implementations were found:
<i32 as Bar>

View File

@ -18,7 +18,7 @@ LL | enum MList { Cons(isize, MList), Nil }
| ^^^^^^^^^^
|
= note: ...which again requires computing drop-check constraints for `MList`, completing the cycle
= note: cycle used when computing dropck types for `Canonical { max_universe: U0, variables: [], value: ParamEnvAnd { param_env: ParamEnv { caller_bounds: [], reveal: UserFacing, def_id: None }, value: MList } }`
= note: cycle used when computing dropck types for `Canonical { max_universe: U0, variables: [], value: ParamEnvAnd { param_env: ParamEnv { caller_bounds: [], reveal: UserFacing }, value: MList } }`
error: aborting due to 2 previous errors