diff options
15 files changed, 152 insertions, 111 deletions
diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/mod.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/mod.rs index 74f27e85cba..7a060cafeab 100644 --- a/compiler/rustc_hir_typeck/src/fn_ctxt/mod.rs +++ b/compiler/rustc_hir_typeck/src/fn_ctxt/mod.rs @@ -21,7 +21,6 @@ use rustc_middle::ty::{self, Const, Ty, TyCtxt, TypeVisitableExt}; use rustc_session::Session; use rustc_span::{self, DUMMY_SP, ErrorGuaranteed, Ident, Span, sym}; use rustc_trait_selection::error_reporting::TypeErrCtxt; -use rustc_trait_selection::error_reporting::infer::sub_relations::SubRelations; use rustc_trait_selection::traits::{ self, FulfillmentError, ObligationCause, ObligationCauseCode, ObligationCtxt, }; @@ -188,14 +187,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { /// /// [`InferCtxtErrorExt::err_ctxt`]: rustc_trait_selection::error_reporting::InferCtxtErrorExt::err_ctxt pub(crate) fn err_ctxt(&'a self) -> TypeErrCtxt<'a, 'tcx> { - let mut sub_relations = SubRelations::default(); - sub_relations.add_constraints( - self, - self.fulfillment_cx.borrow_mut().pending_obligations().iter().map(|o| o.predicate), - ); TypeErrCtxt { infcx: &self.infcx, - sub_relations: RefCell::new(sub_relations), typeck_results: Some(self.typeck_results.borrow()), fallback_has_occurred: self.fallback_has_occurred.get(), normalize_fn_sig: Box::new(|fn_sig| { diff --git a/compiler/rustc_infer/src/infer/context.rs b/compiler/rustc_infer/src/infer/context.rs index 8265fccabc9..efd623fac78 100644 --- a/compiler/rustc_infer/src/infer/context.rs +++ b/compiler/rustc_infer/src/infer/context.rs @@ -179,6 +179,10 @@ impl<'tcx> rustc_type_ir::InferCtxtLike for InferCtxt<'tcx> { self.inner.borrow_mut().type_variables().equate(a, b); } + fn sub_ty_vids_raw(&self, a: ty::TyVid, b: ty::TyVid) { + self.sub_ty_vids_raw(a, b); + } + fn equate_int_vids_raw(&self, a: ty::IntVid, b: ty::IntVid) { self.inner.borrow_mut().int_unification_table().union(a, b); } diff --git a/compiler/rustc_infer/src/infer/mod.rs b/compiler/rustc_infer/src/infer/mod.rs index d105d24bed7..48dd699cd50 100644 --- a/compiler/rustc_infer/src/infer/mod.rs +++ b/compiler/rustc_infer/src/infer/mod.rs @@ -764,6 +764,7 @@ impl<'tcx> InferCtxt<'tcx> { let r_b = self.shallow_resolve(predicate.skip_binder().b); match (r_a.kind(), r_b.kind()) { (&ty::Infer(ty::TyVar(a_vid)), &ty::Infer(ty::TyVar(b_vid))) => { + self.sub_ty_vids_raw(a_vid, b_vid); return Err((a_vid, b_vid)); } _ => {} @@ -1128,6 +1129,14 @@ impl<'tcx> InferCtxt<'tcx> { self.inner.borrow_mut().type_variables().root_var(var) } + pub fn sub_ty_vids_raw(&self, a: ty::TyVid, b: ty::TyVid) { + self.inner.borrow_mut().type_variables().sub(a, b); + } + + pub fn sub_root_var(&self, var: ty::TyVid) -> ty::TyVid { + self.inner.borrow_mut().type_variables().sub_root_var(var) + } + pub fn root_const_var(&self, var: ty::ConstVid) -> ty::ConstVid { self.inner.borrow_mut().const_unification_table().find(var).vid } diff --git a/compiler/rustc_infer/src/infer/relate/generalize.rs b/compiler/rustc_infer/src/infer/relate/generalize.rs index a000bb1123c..2323add0b32 100644 --- a/compiler/rustc_infer/src/infer/relate/generalize.rs +++ b/compiler/rustc_infer/src/infer/relate/generalize.rs @@ -519,6 +519,10 @@ impl<'tcx> TypeRelation<TyCtxt<'tcx>> for Generalizer<'_, 'tcx> { let origin = inner.type_variables().var_origin(vid); let new_var_id = inner.type_variables().new_var(self.for_universe, origin); + // Record that `vid` and `new_var_id` have to be subtypes + // of each other. This is currently only used for diagnostics. + // To see why, see the docs in the `type_variables` module. + inner.type_variables().sub(vid, new_var_id); // If we're in the new solver and create a new inference // variable inside of an alias we eagerly constrain that // inference variable to prevent unexpected ambiguity errors. diff --git a/compiler/rustc_infer/src/infer/snapshot/undo_log.rs b/compiler/rustc_infer/src/infer/snapshot/undo_log.rs index fcc0ab3af41..22c815fb87c 100644 --- a/compiler/rustc_infer/src/infer/snapshot/undo_log.rs +++ b/compiler/rustc_infer/src/infer/snapshot/undo_log.rs @@ -20,7 +20,7 @@ pub struct Snapshot<'tcx> { pub(crate) enum UndoLog<'tcx> { DuplicateOpaqueType, OpaqueTypes(OpaqueTypeKey<'tcx>, Option<OpaqueHiddenType<'tcx>>), - TypeVariables(sv::UndoLog<ut::Delegate<type_variable::TyVidEqKey<'tcx>>>), + TypeVariables(type_variable::UndoLog<'tcx>), ConstUnificationTable(sv::UndoLog<ut::Delegate<ConstVidKey<'tcx>>>), IntUnificationTable(sv::UndoLog<ut::Delegate<ty::IntVid>>), FloatUnificationTable(sv::UndoLog<ut::Delegate<ty::FloatVid>>), @@ -49,6 +49,8 @@ impl_from! { RegionConstraintCollector(region_constraints::UndoLog<'tcx>), TypeVariables(sv::UndoLog<ut::Delegate<type_variable::TyVidEqKey<'tcx>>>), + TypeVariables(sv::UndoLog<ut::Delegate<type_variable::TyVidSubKey>>), + TypeVariables(type_variable::UndoLog<'tcx>), IntUnificationTable(sv::UndoLog<ut::Delegate<ty::IntVid>>), FloatUnificationTable(sv::UndoLog<ut::Delegate<ty::FloatVid>>), diff --git a/compiler/rustc_infer/src/infer/type_variable.rs b/compiler/rustc_infer/src/infer/type_variable.rs index 6f6791804d3..613e5a5883a 100644 --- a/compiler/rustc_infer/src/infer/type_variable.rs +++ b/compiler/rustc_infer/src/infer/type_variable.rs @@ -13,12 +13,48 @@ use tracing::debug; use crate::infer::InferCtxtUndoLogs; +/// Represents a single undo-able action that affects a type inference variable. +#[derive(Clone)] +pub(crate) enum UndoLog<'tcx> { + EqRelation(sv::UndoLog<ut::Delegate<TyVidEqKey<'tcx>>>), + SubRelation(sv::UndoLog<ut::Delegate<TyVidSubKey>>), +} + +/// Convert from a specific kind of undo to the more general UndoLog +impl<'tcx> From<sv::UndoLog<ut::Delegate<TyVidEqKey<'tcx>>>> for UndoLog<'tcx> { + fn from(l: sv::UndoLog<ut::Delegate<TyVidEqKey<'tcx>>>) -> Self { + UndoLog::EqRelation(l) + } +} + +/// Convert from a specific kind of undo to the more general UndoLog +impl<'tcx> From<sv::UndoLog<ut::Delegate<TyVidSubKey>>> for UndoLog<'tcx> { + fn from(l: sv::UndoLog<ut::Delegate<TyVidSubKey>>) -> Self { + UndoLog::SubRelation(l) + } +} + impl<'tcx> Rollback<sv::UndoLog<ut::Delegate<TyVidEqKey<'tcx>>>> for TypeVariableStorage<'tcx> { fn reverse(&mut self, undo: sv::UndoLog<ut::Delegate<TyVidEqKey<'tcx>>>) { self.eq_relations.reverse(undo) } } +impl<'tcx> Rollback<sv::UndoLog<ut::Delegate<TyVidSubKey>>> for TypeVariableStorage<'tcx> { + fn reverse(&mut self, undo: sv::UndoLog<ut::Delegate<TyVidSubKey>>) { + self.sub_relations.reverse(undo) + } +} + +impl<'tcx> Rollback<UndoLog<'tcx>> for TypeVariableStorage<'tcx> { + fn reverse(&mut self, undo: UndoLog<'tcx>) { + match undo { + UndoLog::EqRelation(undo) => self.eq_relations.reverse(undo), + UndoLog::SubRelation(undo) => self.sub_relations.reverse(undo), + } + } +} + #[derive(Clone, Default)] pub(crate) struct TypeVariableStorage<'tcx> { /// The origins of each type variable. @@ -27,6 +63,23 @@ pub(crate) struct TypeVariableStorage<'tcx> { /// constraint `?X == ?Y`. This table also stores, for each key, /// the known value. eq_relations: ut::UnificationTableStorage<TyVidEqKey<'tcx>>, + /// Only used by `-Znext-solver` and for diagnostics. + /// + /// When reporting ambiguity errors, we sometimes want to + /// treat all inference vars which are subtypes of each + /// others as if they are equal. For this case we compute + /// the transitive closure of our subtype obligations here. + /// + /// E.g. when encountering ambiguity errors, we want to suggest + /// specifying some method argument or to add a type annotation + /// to a local variable. Because subtyping cannot change the + /// shape of a type, it's fine if the cause of the ambiguity error + /// is only related to the suggested variable via subtyping. + /// + /// Even for something like `let x = returns_arg(); x.method();` the + /// type of `x` is only a supertype of the argument of `returns_arg`. We + /// still want to suggest specifying the type of the argument. + sub_relations: ut::UnificationTableStorage<TyVidSubKey>, } pub(crate) struct TypeVariableTable<'a, 'tcx> { @@ -109,6 +162,16 @@ impl<'tcx> TypeVariableTable<'_, 'tcx> { debug_assert!(self.probe(a).is_unknown()); debug_assert!(self.probe(b).is_unknown()); self.eq_relations().union(a, b); + self.sub_relations().union(a, b); + } + + /// Records that `a <: b`, depending on `dir`. + /// + /// Precondition: neither `a` nor `b` are known. + pub(crate) fn sub(&mut self, a: ty::TyVid, b: ty::TyVid) { + debug_assert!(self.probe(a).is_unknown()); + debug_assert!(self.probe(b).is_unknown()); + self.sub_relations().union(a, b); } /// Instantiates `vid` with the type `ty`. @@ -142,6 +205,10 @@ impl<'tcx> TypeVariableTable<'_, 'tcx> { origin: TypeVariableOrigin, ) -> ty::TyVid { let eq_key = self.eq_relations().new_key(TypeVariableValue::Unknown { universe }); + + let sub_key = self.sub_relations().new_key(()); + debug_assert_eq!(eq_key.vid, sub_key.vid); + let index = self.storage.values.push(TypeVariableData { origin }); debug_assert_eq!(eq_key.vid, index); @@ -164,6 +231,18 @@ impl<'tcx> TypeVariableTable<'_, 'tcx> { self.eq_relations().find(vid).vid } + /// Returns the "root" variable of `vid` in the `sub_relations` + /// equivalence table. All type variables that have been are + /// related via equality or subtyping will yield the same root + /// variable (per the union-find algorithm), so `sub_root_var(a) + /// == sub_root_var(b)` implies that: + /// ```text + /// exists X. (a <: X || X <: a) && (b <: X || X <: b) + /// ``` + pub(crate) fn sub_root_var(&mut self, vid: ty::TyVid) -> ty::TyVid { + self.sub_relations().find(vid).vid + } + /// Retrieves the type to which `vid` has been instantiated, if /// any. pub(crate) fn probe(&mut self, vid: ty::TyVid) -> TypeVariableValue<'tcx> { @@ -181,6 +260,11 @@ impl<'tcx> TypeVariableTable<'_, 'tcx> { self.storage.eq_relations.with_log(self.undo_log) } + #[inline] + fn sub_relations(&mut self) -> super::UnificationTable<'_, 'tcx, TyVidSubKey> { + self.storage.sub_relations.with_log(self.undo_log) + } + /// Returns a range of the type variables created during the snapshot. pub(crate) fn vars_since_snapshot( &mut self, @@ -243,6 +327,33 @@ impl<'tcx> ut::UnifyKey for TyVidEqKey<'tcx> { } } +#[derive(Copy, Clone, Debug, PartialEq, Eq)] +pub(crate) struct TyVidSubKey { + vid: ty::TyVid, +} + +impl From<ty::TyVid> for TyVidSubKey { + #[inline] // make this function eligible for inlining - it is quite hot. + fn from(vid: ty::TyVid) -> Self { + TyVidSubKey { vid } + } +} + +impl ut::UnifyKey for TyVidSubKey { + type Value = (); + #[inline] + fn index(&self) -> u32 { + self.vid.as_u32() + } + #[inline] + fn from_index(i: u32) -> TyVidSubKey { + TyVidSubKey { vid: ty::TyVid::from_u32(i) } + } + fn tag() -> &'static str { + "TyVidSubKey" + } +} + impl<'tcx> ut::UnifyValue for TypeVariableValue<'tcx> { type Error = ut::NoError; diff --git a/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/mod.rs b/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/mod.rs index 443aebbdb4d..f0f95e53265 100644 --- a/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/mod.rs +++ b/compiler/rustc_next_trait_solver/src/solve/eval_ctxt/mod.rs @@ -900,6 +900,10 @@ where && goal.param_env.visit_with(&mut visitor).is_continue() } + pub(super) fn sub_ty_vids_raw(&self, a: ty::TyVid, b: ty::TyVid) { + self.delegate.sub_ty_vids_raw(a, b) + } + #[instrument(level = "trace", skip(self, param_env), ret)] pub(super) fn eq<T: Relate<I>>( &mut self, diff --git a/compiler/rustc_next_trait_solver/src/solve/mod.rs b/compiler/rustc_next_trait_solver/src/solve/mod.rs index 85f9d852d95..a2db21796a2 100644 --- a/compiler/rustc_next_trait_solver/src/solve/mod.rs +++ b/compiler/rustc_next_trait_solver/src/solve/mod.rs @@ -119,11 +119,15 @@ where #[instrument(level = "trace", skip(self))] fn compute_subtype_goal(&mut self, goal: Goal<I, ty::SubtypePredicate<I>>) -> QueryResult<I> { - if goal.predicate.a.is_ty_var() && goal.predicate.b.is_ty_var() { - self.evaluate_added_goals_and_make_canonical_response(Certainty::AMBIGUOUS) - } else { - self.sub(goal.param_env, goal.predicate.a, goal.predicate.b)?; - self.evaluate_added_goals_and_make_canonical_response(Certainty::Yes) + match (goal.predicate.a.kind(), goal.predicate.b.kind()) { + (ty::Infer(ty::TyVar(a_vid)), ty::Infer(ty::TyVar(b_vid))) => { + self.sub_ty_vids_raw(a_vid, b_vid); + self.evaluate_added_goals_and_make_canonical_response(Certainty::AMBIGUOUS) + } + _ => { + self.sub(goal.param_env, goal.predicate.a, goal.predicate.b)?; + self.evaluate_added_goals_and_make_canonical_response(Certainty::Yes) + } } } diff --git a/compiler/rustc_trait_selection/src/error_reporting/infer/mod.rs b/compiler/rustc_trait_selection/src/error_reporting/infer/mod.rs index 812e20e4338..d3a17232a40 100644 --- a/compiler/rustc_trait_selection/src/error_reporting/infer/mod.rs +++ b/compiler/rustc_trait_selection/src/error_reporting/infer/mod.rs @@ -91,7 +91,6 @@ mod suggest; pub mod need_type_info; pub mod nice_region_error; pub mod region; -pub mod sub_relations; /// Makes a valid string literal from a string by escaping special characters (" and \), /// unless they are already escaped. diff --git a/compiler/rustc_trait_selection/src/error_reporting/infer/need_type_info.rs b/compiler/rustc_trait_selection/src/error_reporting/infer/need_type_info.rs index ec2287ed516..dff1311070c 100644 --- a/compiler/rustc_trait_selection/src/error_reporting/infer/need_type_info.rs +++ b/compiler/rustc_trait_selection/src/error_reporting/infer/need_type_info.rs @@ -894,7 +894,7 @@ impl<'a, 'tcx> FindInferSourceVisitor<'a, 'tcx> { use ty::{Infer, TyVar}; match (inner_ty.kind(), target_ty.kind()) { (&Infer(TyVar(a_vid)), &Infer(TyVar(b_vid))) => { - self.tecx.sub_relations.borrow_mut().unified(self.tecx, a_vid, b_vid) + self.tecx.sub_root_var(a_vid) == self.tecx.sub_root_var(b_vid) } _ => false, } diff --git a/compiler/rustc_trait_selection/src/error_reporting/infer/sub_relations.rs b/compiler/rustc_trait_selection/src/error_reporting/infer/sub_relations.rs deleted file mode 100644 index ef26a8ff7b8..00000000000 --- a/compiler/rustc_trait_selection/src/error_reporting/infer/sub_relations.rs +++ /dev/null @@ -1,81 +0,0 @@ -use rustc_data_structures::fx::FxHashMap; -use rustc_data_structures::undo_log::NoUndo; -use rustc_data_structures::unify as ut; -use rustc_middle::ty; - -use crate::infer::InferCtxt; - -#[derive(Debug, Copy, Clone, PartialEq)] -struct SubId(u32); -impl ut::UnifyKey for SubId { - type Value = (); - #[inline] - fn index(&self) -> u32 { - self.0 - } - #[inline] - fn from_index(i: u32) -> SubId { - SubId(i) - } - fn tag() -> &'static str { - "SubId" - } -} - -/// When reporting ambiguity errors, we sometimes want to -/// treat all inference vars which are subtypes of each -/// others as if they are equal. For this case we compute -/// the transitive closure of our subtype obligations here. -/// -/// E.g. when encountering ambiguity errors, we want to suggest -/// specifying some method argument or to add a type annotation -/// to a local variable. Because subtyping cannot change the -/// shape of a type, it's fine if the cause of the ambiguity error -/// is only related to the suggested variable via subtyping. -/// -/// Even for something like `let x = returns_arg(); x.method();` the -/// type of `x` is only a supertype of the argument of `returns_arg`. We -/// still want to suggest specifying the type of the argument. -#[derive(Default)] -pub struct SubRelations { - map: FxHashMap<ty::TyVid, SubId>, - table: ut::UnificationTableStorage<SubId>, -} - -impl SubRelations { - fn get_id<'tcx>(&mut self, infcx: &InferCtxt<'tcx>, vid: ty::TyVid) -> SubId { - let root_vid = infcx.root_var(vid); - *self.map.entry(root_vid).or_insert_with(|| self.table.with_log(&mut NoUndo).new_key(())) - } - - pub fn add_constraints<'tcx>( - &mut self, - infcx: &InferCtxt<'tcx>, - obls: impl IntoIterator<Item = ty::Predicate<'tcx>>, - ) { - for p in obls { - let (a, b) = match p.kind().skip_binder() { - ty::PredicateKind::Subtype(ty::SubtypePredicate { a_is_expected: _, a, b }) => { - (a, b) - } - ty::PredicateKind::Coerce(ty::CoercePredicate { a, b }) => (a, b), - _ => continue, - }; - - match (a.kind(), b.kind()) { - (&ty::Infer(ty::TyVar(a_vid)), &ty::Infer(ty::TyVar(b_vid))) => { - let a = self.get_id(infcx, a_vid); - let b = self.get_id(infcx, b_vid); - self.table.with_log(&mut NoUndo).unify_var_var(a, b).unwrap(); - } - _ => continue, - } - } - } - - pub fn unified<'tcx>(&mut self, infcx: &InferCtxt<'tcx>, a: ty::TyVid, b: ty::TyVid) -> bool { - let a = self.get_id(infcx, a); - let b = self.get_id(infcx, b); - self.table.with_log(&mut NoUndo).unioned(a, b) - } -} diff --git a/compiler/rustc_trait_selection/src/error_reporting/mod.rs b/compiler/rustc_trait_selection/src/error_reporting/mod.rs index 82695688ae8..cce20b05c79 100644 --- a/compiler/rustc_trait_selection/src/error_reporting/mod.rs +++ b/compiler/rustc_trait_selection/src/error_reporting/mod.rs @@ -7,8 +7,6 @@ use rustc_macros::extension; use rustc_middle::bug; use rustc_middle::ty::{self, Ty}; -use crate::error_reporting::infer::sub_relations; - pub mod infer; pub mod traits; @@ -21,7 +19,6 @@ pub mod traits; /// methods which should not be used during the happy path. pub struct TypeErrCtxt<'a, 'tcx> { pub infcx: &'a InferCtxt<'tcx>, - pub sub_relations: std::cell::RefCell<sub_relations::SubRelations>, pub typeck_results: Option<std::cell::Ref<'a, ty::TypeckResults<'tcx>>>, pub fallback_has_occurred: bool, @@ -38,7 +35,6 @@ impl<'tcx> InferCtxt<'tcx> { fn err_ctxt(&self) -> TypeErrCtxt<'_, 'tcx> { TypeErrCtxt { infcx: self, - sub_relations: Default::default(), typeck_results: None, fallback_has_occurred: false, normalize_fn_sig: Box::new(|fn_sig| fn_sig), diff --git a/compiler/rustc_trait_selection/src/error_reporting/traits/mod.rs b/compiler/rustc_trait_selection/src/error_reporting/traits/mod.rs index c8500b2d9d4..f794ff632c5 100644 --- a/compiler/rustc_trait_selection/src/error_reporting/traits/mod.rs +++ b/compiler/rustc_trait_selection/src/error_reporting/traits/mod.rs @@ -139,10 +139,6 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> { &self, mut errors: Vec<FulfillmentError<'tcx>>, ) -> ErrorGuaranteed { - self.sub_relations - .borrow_mut() - .add_constraints(self, errors.iter().map(|e| e.obligation.predicate)); - #[derive(Debug)] struct ErrorDescriptor<'tcx> { goal: Goal<'tcx, ty::Predicate<'tcx>>, diff --git a/compiler/rustc_trait_selection/src/solve/delegate.rs b/compiler/rustc_trait_selection/src/solve/delegate.rs index e6a2761db5a..448fc025be6 100644 --- a/compiler/rustc_trait_selection/src/solve/delegate.rs +++ b/compiler/rustc_trait_selection/src/solve/delegate.rs @@ -126,13 +126,12 @@ impl<'tcx> rustc_next_trait_solver::delegate::SolverDelegate for SolverDelegate< } ty::PredicateKind::Subtype(ty::SubtypePredicate { a, b, .. }) | ty::PredicateKind::Coerce(ty::CoercePredicate { a, b }) => { - if self.shallow_resolve(a).is_ty_var() && self.shallow_resolve(b).is_ty_var() { - // FIXME: We also need to register a subtype relation between these vars - // when those are added, and if they aren't in the same sub root then - // we should mark this goal as `has_changed`. - Some(Certainty::AMBIGUOUS) - } else { - None + match (self.shallow_resolve(a).kind(), self.shallow_resolve(b).kind()) { + (&ty::Infer(ty::TyVar(a_vid)), &ty::Infer(ty::TyVar(b_vid))) => { + self.sub_ty_vids_raw(a_vid, b_vid); + Some(Certainty::AMBIGUOUS) + } + _ => None, } } ty::PredicateKind::Clause(ty::ClauseKind::ConstArgHasType(ct, _)) => { diff --git a/compiler/rustc_type_ir/src/infer_ctxt.rs b/compiler/rustc_type_ir/src/infer_ctxt.rs index b4462294700..3fac50ff9cc 100644 --- a/compiler/rustc_type_ir/src/infer_ctxt.rs +++ b/compiler/rustc_type_ir/src/infer_ctxt.rs @@ -197,6 +197,7 @@ pub trait InferCtxtLike: Sized { ) -> U; fn equate_ty_vids_raw(&self, a: ty::TyVid, b: ty::TyVid); + fn sub_ty_vids_raw(&self, a: ty::TyVid, b: ty::TyVid); fn equate_int_vids_raw(&self, a: ty::IntVid, b: ty::IntVid); fn equate_float_vids_raw(&self, a: ty::FloatVid, b: ty::FloatVid); fn equate_const_vids_raw(&self, a: ty::ConstVid, b: ty::ConstVid); |