From 7a57a74bf52306d18d265fa4b498064634c91652 Mon Sep 17 00:00:00 2001 From: lcnr Date: Tue, 10 Sep 2024 15:21:57 +0200 Subject: [PATCH] generalize: track relevant info in cache key --- .../rustc_infer/src/infer/relate/generalize.rs | 18 +++++++++--------- .../occurs-check/unused-substs-3.rs | 6 ++++-- .../occurs-check/unused-substs-3.stderr | 8 +++----- 3 files changed, 16 insertions(+), 16 deletions(-) diff --git a/compiler/rustc_infer/src/infer/relate/generalize.rs b/compiler/rustc_infer/src/infer/relate/generalize.rs index f2a511d7a88..fbe64f47741 100644 --- a/compiler/rustc_infer/src/infer/relate/generalize.rs +++ b/compiler/rustc_infer/src/infer/relate/generalize.rs @@ -259,11 +259,11 @@ impl<'tcx> InferCtxt<'tcx> { structurally_relate_aliases, root_vid, for_universe, - ambient_variance, root_term: source_term.into(), + ambient_variance, in_alias: false, - has_unconstrained_ty_var: false, cache: Default::default(), + has_unconstrained_ty_var: false, }; let value_may_be_infer = generalizer.relate(source_term, source_term)?; @@ -304,14 +304,12 @@ struct Generalizer<'me, 'tcx> { /// we reject the relation. for_universe: ty::UniverseIndex, - /// After we generalize this type, we are going to relate it to - /// some other type. What will be the variance at this point? - ambient_variance: ty::Variance, - /// The root term (const or type) we're generalizing. Used for cycle errors. root_term: Term<'tcx>, - cache: SsoHashMap, Ty<'tcx>>, + /// After we generalize this type, we are going to relate it to + /// some other type. What will be the variance at this point? + ambient_variance: ty::Variance, /// This is set once we're generalizing the arguments of an alias. /// @@ -320,6 +318,8 @@ struct Generalizer<'me, 'tcx> { /// hold by either normalizing the outer or the inner associated type. in_alias: bool, + cache: SsoHashMap<(Ty<'tcx>, ty::Variance, bool), Ty<'tcx>>, + /// See the field `has_unconstrained_ty_var` in `Generalization`. has_unconstrained_ty_var: bool, } @@ -451,7 +451,7 @@ impl<'tcx> TypeRelation> for Generalizer<'_, 'tcx> { fn tys(&mut self, t: Ty<'tcx>, t2: Ty<'tcx>) -> RelateResult<'tcx, Ty<'tcx>> { assert_eq!(t, t2); // we are misusing TypeRelation here; both LHS and RHS ought to be == - if let Some(&result) = self.cache.get(&t) { + if let Some(&result) = self.cache.get(&(t, self.ambient_variance, self.in_alias)) { return Ok(result); } @@ -557,7 +557,7 @@ impl<'tcx> TypeRelation> for Generalizer<'_, 'tcx> { _ => relate::structurally_relate_tys(self, t, t), }?; - self.cache.insert(t, g); + self.cache.insert((t, self.ambient_variance, self.in_alias), g); Ok(g) } diff --git a/tests/ui/const-generics/occurs-check/unused-substs-3.rs b/tests/ui/const-generics/occurs-check/unused-substs-3.rs index 6db18d587d3..dfb051192e2 100644 --- a/tests/ui/const-generics/occurs-check/unused-substs-3.rs +++ b/tests/ui/const-generics/occurs-check/unused-substs-3.rs @@ -11,9 +11,11 @@ fn bind() -> (T, [u8; 6 + 1]) { fn main() { let (mut t, foo) = bind(); + //~^ ERROR mismatched types + //~| NOTE cyclic type + // `t` is `ty::Infer(TyVar(?1t))` // `foo` contains `ty::Infer(TyVar(?1t))` in its substs t = foo; - //~^ ERROR mismatched types - //~| NOTE cyclic type + } diff --git a/tests/ui/const-generics/occurs-check/unused-substs-3.stderr b/tests/ui/const-generics/occurs-check/unused-substs-3.stderr index bcb59705c6b..30a2a7901bd 100644 --- a/tests/ui/const-generics/occurs-check/unused-substs-3.stderr +++ b/tests/ui/const-generics/occurs-check/unused-substs-3.stderr @@ -1,10 +1,8 @@ error[E0308]: mismatched types - --> $DIR/unused-substs-3.rs:16:9 + --> $DIR/unused-substs-3.rs:13:24 | -LL | t = foo; - | ^^^- help: try using a conversion method: `.to_vec()` - | | - | cyclic type of infinite size +LL | let (mut t, foo) = bind(); + | ^^^^^^ cyclic type of infinite size error: aborting due to 1 previous error