diff options
5 files changed, 144 insertions, 1 deletions
diff --git a/compiler/rustc_type_ir/src/ty_kind/closure.rs b/compiler/rustc_type_ir/src/ty_kind/closure.rs index 10b164eae02..74e4e035c87 100644 --- a/compiler/rustc_type_ir/src/ty_kind/closure.rs +++ b/compiler/rustc_type_ir/src/ty_kind/closure.rs @@ -3,9 +3,10 @@ use std::ops::ControlFlow; use derive_where::derive_where; use rustc_type_ir_macros::{Lift_Generic, TypeFoldable_Generic, TypeVisitable_Generic}; +use crate::data_structures::DelayedMap; use crate::fold::{TypeFoldable, TypeFolder, TypeSuperFoldable, shift_region}; use crate::inherent::*; -use crate::visit::{TypeSuperVisitable, TypeVisitable, TypeVisitor}; +use crate::visit::{TypeSuperVisitable, TypeVisitable, TypeVisitableExt, TypeVisitor}; use crate::{self as ty, Interner}; /// A closure can be modeled as a struct that looks like: @@ -471,6 +472,7 @@ impl<I: Interner> CoroutineClosureSignature<I> { interner: cx, region: env_region, debruijn: ty::INNERMOST, + cache: Default::default(), }); Ty::new_tup_from_iter( cx, @@ -498,6 +500,10 @@ struct FoldEscapingRegions<I: Interner> { interner: I, debruijn: ty::DebruijnIndex, region: I::Region, + + // Depends on `debruijn` because we may have types with regions of different + // debruijn depths depending on the binders we've entered. + cache: DelayedMap<(ty::DebruijnIndex, I::Ty), I::Ty>, } impl<I: Interner> TypeFolder<I> for FoldEscapingRegions<I> { @@ -505,6 +511,18 @@ impl<I: Interner> TypeFolder<I> for FoldEscapingRegions<I> { self.interner } + fn fold_ty(&mut self, t: I::Ty) -> I::Ty { + if !t.has_vars_bound_at_or_above(self.debruijn) { + t + } else if let Some(&t) = self.cache.get(&(self.debruijn, t)) { + t + } else { + let res = t.super_fold_with(self); + assert!(self.cache.insert((self.debruijn, t), res)); + res + } + } + fn fold_binder<T>(&mut self, t: ty::Binder<I, T>) -> ty::Binder<I, T> where T: TypeFoldable<I>, diff --git a/tests/ui/async-await/async-closures/post-mono-higher-ranked-hang-2.rs b/tests/ui/async-await/async-closures/post-mono-higher-ranked-hang-2.rs new file mode 100644 index 00000000000..4cdf4bf8def --- /dev/null +++ b/tests/ui/async-await/async-closures/post-mono-higher-ranked-hang-2.rs @@ -0,0 +1,23 @@ +//@ edition: 2021 +//@ build-fail + +// Regression test for <https://github.com/rust-lang/rust/issues/135780>. + +use std::future::Future; +use std::ops::AsyncFn; +use std::pin::Pin; + +fn recur<'l>(closure: &'l impl AsyncFn()) -> Pin<Box<dyn Future<Output = ()> + 'l>> { + Box::pin(async move { + let _ = closure(); + let _ = recur(&async || { + //~^ ERROR reached the recursion limit + let _ = closure(); + }); + }) +} + +fn main() { + let closure = async || {}; + let _ = recur(&closure); +} diff --git a/tests/ui/async-await/async-closures/post-mono-higher-ranked-hang-2.stderr b/tests/ui/async-await/async-closures/post-mono-higher-ranked-hang-2.stderr new file mode 100644 index 00000000000..64f4665225f --- /dev/null +++ b/tests/ui/async-await/async-closures/post-mono-higher-ranked-hang-2.stderr @@ -0,0 +1,18 @@ +error: reached the recursion limit while instantiating `recur::<{async closure@$DIR/post-mono-higher-ranked-hang-2.rs:13:24: 13:32}>` + --> $DIR/post-mono-higher-ranked-hang-2.rs:13:17 + | +LL | let _ = recur(&async || { + | _________________^ +LL | | +LL | | let _ = closure(); +LL | | }); + | |__________^ + | +note: `recur` defined here + --> $DIR/post-mono-higher-ranked-hang-2.rs:10:1 + | +LL | fn recur<'l>(closure: &'l impl AsyncFn()) -> Pin<Box<dyn Future<Output = ()> + 'l>> { + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: aborting due to 1 previous error + diff --git a/tests/ui/async-await/async-closures/post-mono-higher-ranked-hang.rs b/tests/ui/async-await/async-closures/post-mono-higher-ranked-hang.rs new file mode 100644 index 00000000000..f6ebf787f81 --- /dev/null +++ b/tests/ui/async-await/async-closures/post-mono-higher-ranked-hang.rs @@ -0,0 +1,63 @@ +//@ build-fail +//@ aux-build:block-on.rs +//@ edition:2021 + +// Regression test for <https://github.com/rust-lang/rust/issues/135780>. + +extern crate block_on; + +use std::future::Future; +use std::ops::AsyncFnMut; +use std::pin::{Pin, pin}; +use std::task::*; + +trait Db {} + +impl Db for () {} + +struct Env<'db> { + db: &'db (), +} + +#[derive(Debug)] +enum SymPerm<'db> { + Dummy(&'db ()), + Apply(Box<SymPerm<'db>>, Box<SymPerm<'db>>), +} + +pub struct ToChain<'env, 'db> { + db: &'db dyn crate::Db, + env: &'env Env<'db>, +} + +impl<'env, 'db> ToChain<'env, 'db> { + fn perm_pairs<'l>( + &'l self, + perm: &'l SymPerm<'db>, + yield_chain: &'l mut impl AsyncFnMut(&SymPerm<'db>), + ) -> Pin<Box<dyn std::future::Future<Output = ()> + 'l>> { + Box::pin(async move { + match perm { + SymPerm::Dummy(_) => yield_chain(perm).await, + SymPerm::Apply(l, r) => { + self.perm_pairs(l, &mut async move |left_pair| { + //~^ ERROR reached the recursion limit while instantiating + self.perm_pairs(r, yield_chain).await + }) + .await + } + } + }) + } +} + +fn main() { + block_on::block_on(async { + let pair = SymPerm::Apply(Box::new(SymPerm::Dummy(&())), Box::new(SymPerm::Dummy(&()))); + ToChain { db: &(), env: &Env { db: &() } } + .perm_pairs(&pair, &mut async |p| { + eprintln!("{p:?}"); + }) + .await; + }); +} diff --git a/tests/ui/async-await/async-closures/post-mono-higher-ranked-hang.stderr b/tests/ui/async-await/async-closures/post-mono-higher-ranked-hang.stderr new file mode 100644 index 00000000000..486e5f94165 --- /dev/null +++ b/tests/ui/async-await/async-closures/post-mono-higher-ranked-hang.stderr @@ -0,0 +1,21 @@ +error: reached the recursion limit while instantiating `ToChain::<'_, '_>::perm_pairs::<{async closure@$DIR/post-mono-higher-ranked-hang.rs:43:45: 43:67}>` + --> $DIR/post-mono-higher-ranked-hang.rs:43:21 + | +LL | / self.perm_pairs(l, &mut async move |left_pair| { +LL | | +LL | | self.perm_pairs(r, yield_chain).await +LL | | }) + | |______________________^ + | +note: `ToChain::<'env, 'db>::perm_pairs` defined here + --> $DIR/post-mono-higher-ranked-hang.rs:34:5 + | +LL | / fn perm_pairs<'l>( +LL | | &'l self, +LL | | perm: &'l SymPerm<'db>, +LL | | yield_chain: &'l mut impl AsyncFnMut(&SymPerm<'db>), +LL | | ) -> Pin<Box<dyn std::future::Future<Output = ()> + 'l>> { + | |____________________________________________________________^ + +error: aborting due to 1 previous error + |