From b7297ac4407e25f7872cd061246196cd4c8b485b Mon Sep 17 00:00:00 2001
From: Michael Goulet <michael@errs.io>
Date: Sun, 29 Sep 2024 13:08:48 -0400
Subject: [PATCH 1/4] Add gate for precise capturing in traits
---
compiler/rustc_ast_lowering/src/lib.rs | 19 ++++++++++++++-----
compiler/rustc_feature/src/unstable.rs | 2 ++
compiler/rustc_span/src/symbol.rs | 1 +
...eature-gate-precise_capturing_in_traits.rs | 6 ++++++
...re-gate-precise_capturing_in_traits.stderr | 13 +++++++++++++
.../forgot-to-capture-type.stderr | 3 +++
.../precise-capturing/redundant.rpitit.stderr | 6 ++++++
...itit-captures-more-method-lifetimes.stderr | 3 +++
.../precise-capturing/rpitit.stderr | 3 +++
.../precise-capturing/self-capture.stderr | 3 +++
10 files changed, 54 insertions(+), 5 deletions(-)
create mode 100644 tests/ui/feature-gates/feature-gate-precise_capturing_in_traits.rs
create mode 100644 tests/ui/feature-gates/feature-gate-precise_capturing_in_traits.stderr
diff --git a/compiler/rustc_ast_lowering/src/lib.rs b/compiler/rustc_ast_lowering/src/lib.rs
index b26797f42032f..35af4d63cc760 100644
--- a/compiler/rustc_ast_lowering/src/lib.rs
+++ b/compiler/rustc_ast_lowering/src/lib.rs
@@ -1573,11 +1573,20 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
// Feature gate for RPITIT + use<..>
match origin {
rustc_hir::OpaqueTyOrigin::FnReturn { in_trait_or_impl: Some(_), .. } => {
- if let Some(span) = bounds.iter().find_map(|bound| match *bound {
- ast::GenericBound::Use(_, span) => Some(span),
- _ => None,
- }) {
- self.tcx.dcx().emit_err(errors::NoPreciseCapturesOnRpitit { span });
+ if !self.tcx.features().precise_capturing_in_traits
+ && let Some(span) = bounds.iter().find_map(|bound| match *bound {
+ ast::GenericBound::Use(_, span) => Some(span),
+ _ => None,
+ })
+ {
+ let mut diag =
+ self.tcx.dcx().create_err(errors::NoPreciseCapturesOnRpitit { span });
+ add_feature_diagnostics(
+ &mut diag,
+ self.tcx.sess,
+ sym::precise_capturing_in_traits,
+ );
+ diag.emit();
}
}
_ => {}
diff --git a/compiler/rustc_feature/src/unstable.rs b/compiler/rustc_feature/src/unstable.rs
index 380e36fe40566..19a6960cf4d88 100644
--- a/compiler/rustc_feature/src/unstable.rs
+++ b/compiler/rustc_feature/src/unstable.rs
@@ -565,6 +565,8 @@ declare_features! (
(incomplete, pin_ergonomics, "CURRENT_RUSTC_VERSION", Some(130494)),
/// Allows postfix match `expr.match { ... }`
(unstable, postfix_match, "1.79.0", Some(121618)),
+ /// Allows `use<..>` precise capturign on impl Trait in traits.
+ (unstable, precise_capturing_in_traits, "CURRENT_RUSTC_VERSION", Some(130044)),
/// Allows macro attributes on expressions, statements and non-inline modules.
(unstable, proc_macro_hygiene, "1.30.0", Some(54727)),
/// Makes `&` and `&mut` patterns eat only one layer of references in Rust 2024.
diff --git a/compiler/rustc_span/src/symbol.rs b/compiler/rustc_span/src/symbol.rs
index 1527600e764c0..683f59a89995e 100644
--- a/compiler/rustc_span/src/symbol.rs
+++ b/compiler/rustc_span/src/symbol.rs
@@ -1479,6 +1479,7 @@ symbols! {
powif64,
pre_dash_lto: "pre-lto",
precise_capturing,
+ precise_capturing_in_traits,
precise_pointer_size_matching,
pref_align_of,
prefetch_read_data,
diff --git a/tests/ui/feature-gates/feature-gate-precise_capturing_in_traits.rs b/tests/ui/feature-gates/feature-gate-precise_capturing_in_traits.rs
new file mode 100644
index 0000000000000..308b41dfc68ab
--- /dev/null
+++ b/tests/ui/feature-gates/feature-gate-precise_capturing_in_traits.rs
@@ -0,0 +1,6 @@
+trait Foo {
+ fn test() -> impl Sized + use<Self>;
+ //~^ ERROR `use<...>` precise capturing syntax is currently not allowed in return-position
+}
+
+fn main() {}
diff --git a/tests/ui/feature-gates/feature-gate-precise_capturing_in_traits.stderr b/tests/ui/feature-gates/feature-gate-precise_capturing_in_traits.stderr
new file mode 100644
index 0000000000000..b2c6bf61124d9
--- /dev/null
+++ b/tests/ui/feature-gates/feature-gate-precise_capturing_in_traits.stderr
@@ -0,0 +1,13 @@
+error: `use<...>` precise capturing syntax is currently not allowed in return-position `impl Trait` in traits
+ --> $DIR/feature-gate-precise_capturing_in_traits.rs:2:31
+ |
+LL | fn test() -> impl Sized + use<Self>;
+ | ^^^^^^^^^
+ |
+ = note: currently, return-position `impl Trait` in traits and trait implementations capture all lifetimes in scope
+ = note: see issue #130044 <https://github.com/rust-lang/rust/issues/130044> for more information
+ = help: add `#![feature(precise_capturing_in_traits)]` to the crate attributes to enable
+ = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
+
+error: aborting due to 1 previous error
+
diff --git a/tests/ui/impl-trait/precise-capturing/forgot-to-capture-type.stderr b/tests/ui/impl-trait/precise-capturing/forgot-to-capture-type.stderr
index d9be9d543e450..23d6a3bd11e82 100644
--- a/tests/ui/impl-trait/precise-capturing/forgot-to-capture-type.stderr
+++ b/tests/ui/impl-trait/precise-capturing/forgot-to-capture-type.stderr
@@ -5,6 +5,9 @@ LL | fn bar() -> impl Sized + use<>;
| ^^^^^
|
= note: currently, return-position `impl Trait` in traits and trait implementations capture all lifetimes in scope
+ = note: see issue #130044 <https://github.com/rust-lang/rust/issues/130044> for more information
+ = help: add `#![feature(precise_capturing_in_traits)]` to the crate attributes to enable
+ = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
error: `impl Trait` must mention all type parameters in scope in `use<...>`
--> $DIR/forgot-to-capture-type.rs:1:23
diff --git a/tests/ui/impl-trait/precise-capturing/redundant.rpitit.stderr b/tests/ui/impl-trait/precise-capturing/redundant.rpitit.stderr
index 213888356e572..27f8ff92d3e65 100644
--- a/tests/ui/impl-trait/precise-capturing/redundant.rpitit.stderr
+++ b/tests/ui/impl-trait/precise-capturing/redundant.rpitit.stderr
@@ -5,6 +5,9 @@ LL | fn in_trait() -> impl Sized + use<'a, Self>;
| ^^^^^^^^^^^^^
|
= note: currently, return-position `impl Trait` in traits and trait implementations capture all lifetimes in scope
+ = note: see issue #130044 <https://github.com/rust-lang/rust/issues/130044> for more information
+ = help: add `#![feature(precise_capturing_in_traits)]` to the crate attributes to enable
+ = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
error: `use<...>` precise capturing syntax is currently not allowed in return-position `impl Trait` in traits
--> $DIR/redundant.rs:21:35
@@ -13,6 +16,9 @@ LL | fn in_trait() -> impl Sized + use<'a> {}
| ^^^^^^^
|
= note: currently, return-position `impl Trait` in traits and trait implementations capture all lifetimes in scope
+ = note: see issue #130044 <https://github.com/rust-lang/rust/issues/130044> for more information
+ = help: add `#![feature(precise_capturing_in_traits)]` to the crate attributes to enable
+ = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
error: aborting due to 2 previous errors
diff --git a/tests/ui/impl-trait/precise-capturing/rpitit-captures-more-method-lifetimes.stderr b/tests/ui/impl-trait/precise-capturing/rpitit-captures-more-method-lifetimes.stderr
index b390a23eef414..ffd9646a4038b 100644
--- a/tests/ui/impl-trait/precise-capturing/rpitit-captures-more-method-lifetimes.stderr
+++ b/tests/ui/impl-trait/precise-capturing/rpitit-captures-more-method-lifetimes.stderr
@@ -5,6 +5,9 @@ LL | fn bar<'tr: 'tr>(&'tr mut self) -> impl Sized + use<Self>;
| ^^^^^^^^^
|
= note: currently, return-position `impl Trait` in traits and trait implementations capture all lifetimes in scope
+ = note: see issue #130044 <https://github.com/rust-lang/rust/issues/130044> for more information
+ = help: add `#![feature(precise_capturing_in_traits)]` to the crate attributes to enable
+ = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
error: return type captures more lifetimes than trait definition
--> $DIR/rpitit-captures-more-method-lifetimes.rs:11:40
diff --git a/tests/ui/impl-trait/precise-capturing/rpitit.stderr b/tests/ui/impl-trait/precise-capturing/rpitit.stderr
index 5a120df9f047a..c162875f327cc 100644
--- a/tests/ui/impl-trait/precise-capturing/rpitit.stderr
+++ b/tests/ui/impl-trait/precise-capturing/rpitit.stderr
@@ -5,6 +5,9 @@ LL | fn hello() -> impl PartialEq + use<Self>;
| ^^^^^^^^^
|
= note: currently, return-position `impl Trait` in traits and trait implementations capture all lifetimes in scope
+ = note: see issue #130044 <https://github.com/rust-lang/rust/issues/130044> for more information
+ = help: add `#![feature(precise_capturing_in_traits)]` to the crate attributes to enable
+ = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
error: `impl Trait` captures lifetime parameter, but it is not mentioned in `use<...>` precise captures list
--> $DIR/rpitit.rs:9:19
diff --git a/tests/ui/impl-trait/precise-capturing/self-capture.stderr b/tests/ui/impl-trait/precise-capturing/self-capture.stderr
index c1974600f30c5..45ebc429d88a7 100644
--- a/tests/ui/impl-trait/precise-capturing/self-capture.stderr
+++ b/tests/ui/impl-trait/precise-capturing/self-capture.stderr
@@ -5,6 +5,9 @@ LL | fn bar<'a>() -> impl Sized + use<Self>;
| ^^^^^^^^^
|
= note: currently, return-position `impl Trait` in traits and trait implementations capture all lifetimes in scope
+ = note: see issue #130044 <https://github.com/rust-lang/rust/issues/130044> for more information
+ = help: add `#![feature(precise_capturing_in_traits)]` to the crate attributes to enable
+ = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
error: aborting due to 1 previous error
From a7dc98733da8b84cfc21a538541a41803c4529a0 Mon Sep 17 00:00:00 2001
From: Michael Goulet <michael@errs.io>
Date: Sun, 29 Sep 2024 13:41:13 -0400
Subject: [PATCH 2/4] Add variances to RPITITs
---
.../rustc_hir_analysis/src/variance/mod.rs | 49 +++++++++++++--
compiler/rustc_metadata/src/rmeta/encoder.rs | 5 +-
compiler/rustc_middle/src/ty/context.rs | 4 ++
compiler/rustc_type_ir/src/interner.rs | 2 +
compiler/rustc_type_ir/src/relate.rs | 10 ++++
tests/ui/impl-trait/in-trait/variance.rs | 23 ++++----
tests/ui/impl-trait/in-trait/variance.stderr | 34 +++++++----
.../forgot-to-capture-type.rs | 3 +-
.../forgot-to-capture-type.stderr | 17 +-----
.../precise-capturing/redundant.normal.stderr | 20 -------
.../precise-capturing/redundant.rpitit.stderr | 24 --------
.../impl-trait/precise-capturing/redundant.rs | 15 +++--
.../precise-capturing/redundant.stderr | 36 +++++++++++
.../rpitit-captures-more-method-lifetimes.rs | 5 +-
...itit-captures-more-method-lifetimes.stderr | 23 ++------
.../rpitit-impl-captures-too-much.rs | 14 +++++
.../rpitit-impl-captures-too-much.stderr | 17 ++++++
.../ui/impl-trait/precise-capturing/rpitit.rs | 31 +++++++---
.../precise-capturing/rpitit.stderr | 59 ++++++++-----------
.../precise-capturing/self-capture.rs | 5 +-
.../precise-capturing/self-capture.stderr | 13 ----
21 files changed, 241 insertions(+), 168 deletions(-)
delete mode 100644 tests/ui/impl-trait/precise-capturing/redundant.normal.stderr
delete mode 100644 tests/ui/impl-trait/precise-capturing/redundant.rpitit.stderr
create mode 100644 tests/ui/impl-trait/precise-capturing/redundant.stderr
create mode 100644 tests/ui/impl-trait/precise-capturing/rpitit-impl-captures-too-much.rs
create mode 100644 tests/ui/impl-trait/precise-capturing/rpitit-impl-captures-too-much.stderr
delete mode 100644 tests/ui/impl-trait/precise-capturing/self-capture.stderr
diff --git a/compiler/rustc_hir_analysis/src/variance/mod.rs b/compiler/rustc_hir_analysis/src/variance/mod.rs
index 12bb9a3f9e0f3..02cfb57b836f6 100644
--- a/compiler/rustc_hir_analysis/src/variance/mod.rs
+++ b/compiler/rustc_hir_analysis/src/variance/mod.rs
@@ -5,6 +5,7 @@
use itertools::Itertools;
use rustc_arena::DroplessArena;
+use rustc_hir as hir;
use rustc_hir::def::DefKind;
use rustc_hir::def_id::{DefId, LocalDefId};
use rustc_middle::query::Providers;
@@ -63,8 +64,29 @@ fn variances_of(tcx: TyCtxt<'_>, item_def_id: LocalDefId) -> &[ty::Variance] {
let crate_map = tcx.crate_variances(());
return crate_map.variances.get(&item_def_id.to_def_id()).copied().unwrap_or(&[]);
}
+ DefKind::AssocTy => match tcx.opt_rpitit_info(item_def_id.to_def_id()) {
+ Some(ty::ImplTraitInTraitData::Trait { opaque_def_id, .. }) => {
+ return variance_of_opaque(
+ tcx,
+ opaque_def_id.expect_local(),
+ ForceCaptureTraitArgs::Yes,
+ );
+ }
+ None | Some(ty::ImplTraitInTraitData::Impl { .. }) => {}
+ },
DefKind::OpaqueTy => {
- return variance_of_opaque(tcx, item_def_id);
+ let force_capture_trait_args = if let hir::OpaqueTyOrigin::FnReturn {
+ parent: _,
+ in_trait_or_impl: Some(hir::RpitContext::Trait),
+ } =
+ tcx.hir_node_by_def_id(item_def_id).expect_opaque_ty().origin
+ {
+ ForceCaptureTraitArgs::Yes
+ } else {
+ ForceCaptureTraitArgs::No
+ };
+
+ return variance_of_opaque(tcx, item_def_id, force_capture_trait_args);
}
_ => {}
}
@@ -73,8 +95,18 @@ fn variances_of(tcx: TyCtxt<'_>, item_def_id: LocalDefId) -> &[ty::Variance] {
span_bug!(tcx.def_span(item_def_id), "asked to compute variance for wrong kind of item");
}
+#[derive(Debug, Copy, Clone)]
+enum ForceCaptureTraitArgs {
+ Yes,
+ No,
+}
+
#[instrument(level = "trace", skip(tcx), ret)]
-fn variance_of_opaque(tcx: TyCtxt<'_>, item_def_id: LocalDefId) -> &[ty::Variance] {
+fn variance_of_opaque(
+ tcx: TyCtxt<'_>,
+ item_def_id: LocalDefId,
+ force_capture_trait_args: ForceCaptureTraitArgs,
+) -> &[ty::Variance] {
let generics = tcx.generics_of(item_def_id);
// Opaque types may only use regions that are bound. So for
@@ -115,9 +147,7 @@ fn variance_of_opaque(tcx: TyCtxt<'_>, item_def_id: LocalDefId) -> &[ty::Varianc
#[instrument(level = "trace", skip(self), ret)]
fn visit_ty(&mut self, t: Ty<'tcx>) {
match t.kind() {
- ty::Alias(_, ty::AliasTy { def_id, args, .. })
- if matches!(self.tcx.def_kind(*def_id), DefKind::OpaqueTy) =>
- {
+ ty::Alias(ty::Opaque, ty::AliasTy { def_id, args, .. }) => {
self.visit_opaque(*def_id, args);
}
_ => t.super_visit_with(self),
@@ -135,6 +165,15 @@ fn variance_of_opaque(tcx: TyCtxt<'_>, item_def_id: LocalDefId) -> &[ty::Varianc
let mut generics = generics;
while let Some(def_id) = generics.parent {
generics = tcx.generics_of(def_id);
+
+ // Don't mark trait params generic if we're in an RPITIT.
+ if matches!(force_capture_trait_args, ForceCaptureTraitArgs::Yes)
+ && generics.parent.is_none()
+ {
+ debug_assert_eq!(tcx.def_kind(def_id), DefKind::Trait);
+ break;
+ }
+
for param in &generics.own_params {
match param.kind {
ty::GenericParamDefKind::Lifetime => {
diff --git a/compiler/rustc_metadata/src/rmeta/encoder.rs b/compiler/rustc_metadata/src/rmeta/encoder.rs
index 610c682d3a461..afe03531861c9 100644
--- a/compiler/rustc_metadata/src/rmeta/encoder.rs
+++ b/compiler/rustc_metadata/src/rmeta/encoder.rs
@@ -1100,9 +1100,12 @@ fn should_encode_variances<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId, def_kind: Def
| DefKind::Fn
| DefKind::Ctor(..)
| DefKind::AssocFn => true,
+ DefKind::AssocTy => {
+ // Only encode variances for RPITITs (for traits)
+ matches!(tcx.opt_rpitit_info(def_id), Some(ty::ImplTraitInTraitData::Trait { .. }))
+ }
DefKind::Mod
| DefKind::Field
- | DefKind::AssocTy
| DefKind::AssocConst
| DefKind::TyParam
| DefKind::ConstParam
diff --git a/compiler/rustc_middle/src/ty/context.rs b/compiler/rustc_middle/src/ty/context.rs
index 90265f67bc1f6..590e1d336f340 100644
--- a/compiler/rustc_middle/src/ty/context.rs
+++ b/compiler/rustc_middle/src/ty/context.rs
@@ -539,6 +539,10 @@ impl<'tcx> Interner for TyCtxt<'tcx> {
self.trait_def(trait_def_id).implement_via_object
}
+ fn is_impl_trait_in_trait(self, def_id: DefId) -> bool {
+ self.is_impl_trait_in_trait(def_id)
+ }
+
fn delay_bug(self, msg: impl ToString) -> ErrorGuaranteed {
self.dcx().span_delayed_bug(DUMMY_SP, msg.to_string())
}
diff --git a/compiler/rustc_type_ir/src/interner.rs b/compiler/rustc_type_ir/src/interner.rs
index a72e7b482a6fd..f06017d7e5c35 100644
--- a/compiler/rustc_type_ir/src/interner.rs
+++ b/compiler/rustc_type_ir/src/interner.rs
@@ -261,6 +261,8 @@ pub trait Interner:
fn trait_may_be_implemented_via_object(self, trait_def_id: Self::DefId) -> bool;
+ fn is_impl_trait_in_trait(self, def_id: Self::DefId) -> bool;
+
fn delay_bug(self, msg: impl ToString) -> Self::ErrorGuaranteed;
fn is_general_coroutine(self, coroutine_def_id: Self::DefId) -> bool;
diff --git a/compiler/rustc_type_ir/src/relate.rs b/compiler/rustc_type_ir/src/relate.rs
index 1302906adab1f..e1f3e493e36e3 100644
--- a/compiler/rustc_type_ir/src/relate.rs
+++ b/compiler/rustc_type_ir/src/relate.rs
@@ -254,6 +254,16 @@ impl<I: Interner> Relate<I> for ty::AliasTy<I> {
b.args,
false, // do not fetch `type_of(a_def_id)`, as it will cause a cycle
)?,
+ ty::Projection if relation.cx().is_impl_trait_in_trait(a.def_id) => {
+ relate_args_with_variances(
+ relation,
+ a.def_id,
+ relation.cx().variances_of(a.def_id),
+ a.args,
+ b.args,
+ false, // do not fetch `type_of(a_def_id)`, as it will cause a cycle
+ )?
+ }
ty::Projection | ty::Weak | ty::Inherent => {
relate_args_invariantly(relation, a.args, b.args)?
}
diff --git a/tests/ui/impl-trait/in-trait/variance.rs b/tests/ui/impl-trait/in-trait/variance.rs
index 0ac44bf7546c2..19905c608e3b5 100644
--- a/tests/ui/impl-trait/in-trait/variance.rs
+++ b/tests/ui/impl-trait/in-trait/variance.rs
@@ -1,22 +1,25 @@
-#![feature(rustc_attrs)]
+#![feature(rustc_attrs, precise_capturing_in_traits)]
#![allow(internal_features)]
#![rustc_variance_of_opaques]
-trait Captures<'a> {}
-impl<T> Captures<'_> for T {}
-
trait Foo<'i> {
fn implicit_capture_early<'a: 'a>() -> impl Sized {}
- //~^ [Self: o, 'i: *, 'a: *, 'a: o, 'i: o]
+ //~^ [Self: o, 'i: o, 'a: *, 'a: o, 'i: o]
+
+ fn explicit_capture_early<'a: 'a>() -> impl Sized + use<'i, 'a, Self> {}
+ //~^ [Self: o, 'i: o, 'a: *, 'i: o, 'a: o]
- fn explicit_capture_early<'a: 'a>() -> impl Sized + Captures<'a> {}
- //~^ [Self: o, 'i: *, 'a: *, 'a: o, 'i: o]
+ fn not_captured_early<'a: 'a>() -> impl Sized + use<'i, Self> {}
+ //~^ [Self: o, 'i: o, 'a: *, 'i: o]
fn implicit_capture_late<'a>(_: &'a ()) -> impl Sized {}
- //~^ [Self: o, 'i: *, 'a: o, 'i: o]
+ //~^ [Self: o, 'i: o, 'a: o, 'i: o]
+
+ fn explicit_capture_late<'a>(_: &'a ()) -> impl Sized + use<'i, 'a, Self> {}
+ //~^ [Self: o, 'i: o, 'i: o, 'a: o]
- fn explicit_capture_late<'a>(_: &'a ()) -> impl Sized + Captures<'a> {}
- //~^ [Self: o, 'i: *, 'a: o, 'i: o]
+ fn not_cpatured_late<'a>(_: &'a ()) -> impl Sized + use<'i, Self> {}
+ //~^ [Self: o, 'i: o, 'i: o]
}
fn main() {}
diff --git a/tests/ui/impl-trait/in-trait/variance.stderr b/tests/ui/impl-trait/in-trait/variance.stderr
index 54e0afbaa950d..f65174e1c358c 100644
--- a/tests/ui/impl-trait/in-trait/variance.stderr
+++ b/tests/ui/impl-trait/in-trait/variance.stderr
@@ -1,26 +1,38 @@
-error: [Self: o, 'i: *, 'a: *, 'a: o, 'i: o]
- --> $DIR/variance.rs:9:44
+error: [Self: o, 'i: o, 'a: *, 'a: o, 'i: o]
+ --> $DIR/variance.rs:6:44
|
LL | fn implicit_capture_early<'a: 'a>() -> impl Sized {}
| ^^^^^^^^^^
-error: [Self: o, 'i: *, 'a: *, 'a: o, 'i: o]
- --> $DIR/variance.rs:12:44
+error: [Self: o, 'i: o, 'a: *, 'i: o, 'a: o]
+ --> $DIR/variance.rs:9:44
+ |
+LL | fn explicit_capture_early<'a: 'a>() -> impl Sized + use<'i, 'a, Self> {}
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: [Self: o, 'i: o, 'a: *, 'i: o]
+ --> $DIR/variance.rs:12:40
|
-LL | fn explicit_capture_early<'a: 'a>() -> impl Sized + Captures<'a> {}
- | ^^^^^^^^^^^^^^^^^^^^^^^^^
+LL | fn not_captured_early<'a: 'a>() -> impl Sized + use<'i, Self> {}
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^
-error: [Self: o, 'i: *, 'a: o, 'i: o]
+error: [Self: o, 'i: o, 'a: o, 'i: o]
--> $DIR/variance.rs:15:48
|
LL | fn implicit_capture_late<'a>(_: &'a ()) -> impl Sized {}
| ^^^^^^^^^^
-error: [Self: o, 'i: *, 'a: o, 'i: o]
+error: [Self: o, 'i: o, 'i: o, 'a: o]
--> $DIR/variance.rs:18:48
|
-LL | fn explicit_capture_late<'a>(_: &'a ()) -> impl Sized + Captures<'a> {}
- | ^^^^^^^^^^^^^^^^^^^^^^^^^
+LL | fn explicit_capture_late<'a>(_: &'a ()) -> impl Sized + use<'i, 'a, Self> {}
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: [Self: o, 'i: o, 'i: o]
+ --> $DIR/variance.rs:21:44
+ |
+LL | fn not_cpatured_late<'a>(_: &'a ()) -> impl Sized + use<'i, Self> {}
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^
-error: aborting due to 4 previous errors
+error: aborting due to 6 previous errors
diff --git a/tests/ui/impl-trait/precise-capturing/forgot-to-capture-type.rs b/tests/ui/impl-trait/precise-capturing/forgot-to-capture-type.rs
index 9d68819f657db..6c2477c9744ab 100644
--- a/tests/ui/impl-trait/precise-capturing/forgot-to-capture-type.rs
+++ b/tests/ui/impl-trait/precise-capturing/forgot-to-capture-type.rs
@@ -1,10 +1,11 @@
+#![feature(precise_capturing_in_traits)]
+
fn type_param<T>() -> impl Sized + use<> {}
//~^ ERROR `impl Trait` must mention all type parameters in scope
trait Foo {
fn bar() -> impl Sized + use<>;
//~^ ERROR `impl Trait` must mention the `Self` type of the trait
- //~| ERROR `use<...>` precise capturing syntax is currently not allowed in return-position `impl Trait` in traits
}
fn main() {}
diff --git a/tests/ui/impl-trait/precise-capturing/forgot-to-capture-type.stderr b/tests/ui/impl-trait/precise-capturing/forgot-to-capture-type.stderr
index 23d6a3bd11e82..93b44a0c18c27 100644
--- a/tests/ui/impl-trait/precise-capturing/forgot-to-capture-type.stderr
+++ b/tests/ui/impl-trait/precise-capturing/forgot-to-capture-type.stderr
@@ -1,16 +1,5 @@
-error: `use<...>` precise capturing syntax is currently not allowed in return-position `impl Trait` in traits
- --> $DIR/forgot-to-capture-type.rs:5:30
- |
-LL | fn bar() -> impl Sized + use<>;
- | ^^^^^
- |
- = note: currently, return-position `impl Trait` in traits and trait implementations capture all lifetimes in scope
- = note: see issue #130044 <https://github.com/rust-lang/rust/issues/130044> for more information
- = help: add `#![feature(precise_capturing_in_traits)]` to the crate attributes to enable
- = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
-
error: `impl Trait` must mention all type parameters in scope in `use<...>`
- --> $DIR/forgot-to-capture-type.rs:1:23
+ --> $DIR/forgot-to-capture-type.rs:3:23
|
LL | fn type_param<T>() -> impl Sized + use<> {}
| - ^^^^^^^^^^^^^^^^^^
@@ -20,7 +9,7 @@ LL | fn type_param<T>() -> impl Sized + use<> {}
= note: currently, all type parameters are required to be mentioned in the precise captures list
error: `impl Trait` must mention the `Self` type of the trait in `use<...>`
- --> $DIR/forgot-to-capture-type.rs:5:17
+ --> $DIR/forgot-to-capture-type.rs:7:17
|
LL | trait Foo {
| --------- `Self` type parameter is implicitly captured by this `impl Trait`
@@ -29,5 +18,5 @@ LL | fn bar() -> impl Sized + use<>;
|
= note: currently, all type parameters are required to be mentioned in the precise captures list
-error: aborting due to 3 previous errors
+error: aborting due to 2 previous errors
diff --git a/tests/ui/impl-trait/precise-capturing/redundant.normal.stderr b/tests/ui/impl-trait/precise-capturing/redundant.normal.stderr
deleted file mode 100644
index d1bcbaa33ae2b..0000000000000
--- a/tests/ui/impl-trait/precise-capturing/redundant.normal.stderr
+++ /dev/null
@@ -1,20 +0,0 @@
-warning: all possible in-scope parameters are already captured, so `use<...>` syntax is redundant
- --> $DIR/redundant.rs:5:19
- |
-LL | fn hello<'a>() -> impl Sized + use<'a> {}
- | ^^^^^^^^^^^^^-------
- | |
- | help: remove the `use<...>` syntax
- |
- = note: `#[warn(impl_trait_redundant_captures)]` on by default
-
-warning: all possible in-scope parameters are already captured, so `use<...>` syntax is redundant
- --> $DIR/redundant.rs:10:27
- |
-LL | fn inherent(&self) -> impl Sized + use<'_> {}
- | ^^^^^^^^^^^^^-------
- | |
- | help: remove the `use<...>` syntax
-
-warning: 2 warnings emitted
-
diff --git a/tests/ui/impl-trait/precise-capturing/redundant.rpitit.stderr b/tests/ui/impl-trait/precise-capturing/redundant.rpitit.stderr
deleted file mode 100644
index 27f8ff92d3e65..0000000000000
--- a/tests/ui/impl-trait/precise-capturing/redundant.rpitit.stderr
+++ /dev/null
@@ -1,24 +0,0 @@
-error: `use<...>` precise capturing syntax is currently not allowed in return-position `impl Trait` in traits
- --> $DIR/redundant.rs:16:35
- |
-LL | fn in_trait() -> impl Sized + use<'a, Self>;
- | ^^^^^^^^^^^^^
- |
- = note: currently, return-position `impl Trait` in traits and trait implementations capture all lifetimes in scope
- = note: see issue #130044 <https://github.com/rust-lang/rust/issues/130044> for more information
- = help: add `#![feature(precise_capturing_in_traits)]` to the crate attributes to enable
- = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
-
-error: `use<...>` precise capturing syntax is currently not allowed in return-position `impl Trait` in traits
- --> $DIR/redundant.rs:21:35
- |
-LL | fn in_trait() -> impl Sized + use<'a> {}
- | ^^^^^^^
- |
- = note: currently, return-position `impl Trait` in traits and trait implementations capture all lifetimes in scope
- = note: see issue #130044 <https://github.com/rust-lang/rust/issues/130044> for more information
- = help: add `#![feature(precise_capturing_in_traits)]` to the crate attributes to enable
- = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
-
-error: aborting due to 2 previous errors
-
diff --git a/tests/ui/impl-trait/precise-capturing/redundant.rs b/tests/ui/impl-trait/precise-capturing/redundant.rs
index 4a08ffb61be03..e19d935f5b0d4 100644
--- a/tests/ui/impl-trait/precise-capturing/redundant.rs
+++ b/tests/ui/impl-trait/precise-capturing/redundant.rs
@@ -1,25 +1,24 @@
//@ compile-flags: -Zunstable-options --edition=2024
-//@ revisions: normal rpitit
-//@[normal] check-pass
+//@ check-pass
+
+#![feature(precise_capturing_in_traits)]
fn hello<'a>() -> impl Sized + use<'a> {}
-//[normal]~^ WARN all possible in-scope parameters are already captured
+//~^ WARN all possible in-scope parameters are already captured
struct Inherent;
impl Inherent {
fn inherent(&self) -> impl Sized + use<'_> {}
- //[normal]~^ WARN all possible in-scope parameters are already captured
+ //~^ WARN all possible in-scope parameters are already captured
}
-#[cfg(rpitit)]
trait Test<'a> {
fn in_trait() -> impl Sized + use<'a, Self>;
- //[rpitit]~^ ERROR `use<...>` precise capturing syntax is currently not allowed in return-position `impl Trait` in traits
+ //~^ WARN all possible in-scope parameters are already captured
}
-#[cfg(rpitit)]
impl<'a> Test<'a> for () {
fn in_trait() -> impl Sized + use<'a> {}
- //[rpitit]~^ ERROR `use<...>` precise capturing syntax is currently not allowed in return-position `impl Trait` in traits
+ //~^ WARN all possible in-scope parameters are already captured
}
fn main() {}
diff --git a/tests/ui/impl-trait/precise-capturing/redundant.stderr b/tests/ui/impl-trait/precise-capturing/redundant.stderr
new file mode 100644
index 0000000000000..274d9d2375f7d
--- /dev/null
+++ b/tests/ui/impl-trait/precise-capturing/redundant.stderr
@@ -0,0 +1,36 @@
+warning: all possible in-scope parameters are already captured, so `use<...>` syntax is redundant
+ --> $DIR/redundant.rs:6:19
+ |
+LL | fn hello<'a>() -> impl Sized + use<'a> {}
+ | ^^^^^^^^^^^^^-------
+ | |
+ | help: remove the `use<...>` syntax
+ |
+ = note: `#[warn(impl_trait_redundant_captures)]` on by default
+
+warning: all possible in-scope parameters are already captured, so `use<...>` syntax is redundant
+ --> $DIR/redundant.rs:11:27
+ |
+LL | fn inherent(&self) -> impl Sized + use<'_> {}
+ | ^^^^^^^^^^^^^-------
+ | |
+ | help: remove the `use<...>` syntax
+
+warning: all possible in-scope parameters are already captured, so `use<...>` syntax is redundant
+ --> $DIR/redundant.rs:16:22
+ |
+LL | fn in_trait() -> impl Sized + use<'a, Self>;
+ | ^^^^^^^^^^^^^-------------
+ | |
+ | help: remove the `use<...>` syntax
+
+warning: all possible in-scope parameters are already captured, so `use<...>` syntax is redundant
+ --> $DIR/redundant.rs:20:22
+ |
+LL | fn in_trait() -> impl Sized + use<'a> {}
+ | ^^^^^^^^^^^^^-------
+ | |
+ | help: remove the `use<...>` syntax
+
+warning: 4 warnings emitted
+
diff --git a/tests/ui/impl-trait/precise-capturing/rpitit-captures-more-method-lifetimes.rs b/tests/ui/impl-trait/precise-capturing/rpitit-captures-more-method-lifetimes.rs
index 062351afecbdf..b39c1408c0509 100644
--- a/tests/ui/impl-trait/precise-capturing/rpitit-captures-more-method-lifetimes.rs
+++ b/tests/ui/impl-trait/precise-capturing/rpitit-captures-more-method-lifetimes.rs
@@ -2,13 +2,14 @@
// trait definition, which is not allowed. Due to the default lifetime capture
// rules of RPITITs, this is only doable if we use precise capturing.
+#![feature(precise_capturing_in_traits)]
+
pub trait Foo {
fn bar<'tr: 'tr>(&'tr mut self) -> impl Sized + use<Self>;
- //~^ ERROR `use<...>` precise capturing syntax is currently not allowed in return-position `impl Trait` in traits
}
impl Foo for () {
- fn bar<'im: 'im>(&'im mut self) -> impl Sized + 'im {}
+ fn bar<'im: 'im>(&'im mut self) -> impl Sized + use<'im> {}
//~^ ERROR return type captures more lifetimes than trait definition
}
diff --git a/tests/ui/impl-trait/precise-capturing/rpitit-captures-more-method-lifetimes.stderr b/tests/ui/impl-trait/precise-capturing/rpitit-captures-more-method-lifetimes.stderr
index ffd9646a4038b..45f755d3cc1be 100644
--- a/tests/ui/impl-trait/precise-capturing/rpitit-captures-more-method-lifetimes.stderr
+++ b/tests/ui/impl-trait/precise-capturing/rpitit-captures-more-method-lifetimes.stderr
@@ -1,28 +1,17 @@
-error: `use<...>` precise capturing syntax is currently not allowed in return-position `impl Trait` in traits
- --> $DIR/rpitit-captures-more-method-lifetimes.rs:6:53
- |
-LL | fn bar<'tr: 'tr>(&'tr mut self) -> impl Sized + use<Self>;
- | ^^^^^^^^^
- |
- = note: currently, return-position `impl Trait` in traits and trait implementations capture all lifetimes in scope
- = note: see issue #130044 <https://github.com/rust-lang/rust/issues/130044> for more information
- = help: add `#![feature(precise_capturing_in_traits)]` to the crate attributes to enable
- = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
-
error: return type captures more lifetimes than trait definition
- --> $DIR/rpitit-captures-more-method-lifetimes.rs:11:40
+ --> $DIR/rpitit-captures-more-method-lifetimes.rs:12:40
|
-LL | fn bar<'im: 'im>(&'im mut self) -> impl Sized + 'im {}
- | --- ^^^^^^^^^^^^^^^^
+LL | fn bar<'im: 'im>(&'im mut self) -> impl Sized + use<'im> {}
+ | --- ^^^^^^^^^^^^^^^^^^^^^
| |
| this lifetime was captured
|
note: hidden type must only reference lifetimes captured by this impl trait
- --> $DIR/rpitit-captures-more-method-lifetimes.rs:6:40
+ --> $DIR/rpitit-captures-more-method-lifetimes.rs:8:40
|
LL | fn bar<'tr: 'tr>(&'tr mut self) -> impl Sized + use<Self>;
| ^^^^^^^^^^^^^^^^^^^^^^
- = note: hidden type inferred to be `impl Sized + 'im`
+ = note: hidden type inferred to be `impl Sized`
-error: aborting due to 2 previous errors
+error: aborting due to 1 previous error
diff --git a/tests/ui/impl-trait/precise-capturing/rpitit-impl-captures-too-much.rs b/tests/ui/impl-trait/precise-capturing/rpitit-impl-captures-too-much.rs
new file mode 100644
index 0000000000000..b16b0522d6e11
--- /dev/null
+++ b/tests/ui/impl-trait/precise-capturing/rpitit-impl-captures-too-much.rs
@@ -0,0 +1,14 @@
+#![feature(precise_capturing_in_traits)]
+
+struct Invariant<'a>(&'a mut &'a mut ());
+
+trait Trait {
+ fn hello(self_: Invariant<'_>) -> impl Sized + use<Self>;
+}
+
+impl Trait for () {
+ fn hello(self_: Invariant<'_>) -> impl Sized + use<'_> {}
+ //~^ ERROR return type captures more lifetimes than trait definition
+}
+
+fn main() {}
diff --git a/tests/ui/impl-trait/precise-capturing/rpitit-impl-captures-too-much.stderr b/tests/ui/impl-trait/precise-capturing/rpitit-impl-captures-too-much.stderr
new file mode 100644
index 0000000000000..e1856b929106e
--- /dev/null
+++ b/tests/ui/impl-trait/precise-capturing/rpitit-impl-captures-too-much.stderr
@@ -0,0 +1,17 @@
+error: return type captures more lifetimes than trait definition
+ --> $DIR/rpitit-impl-captures-too-much.rs:10:39
+ |
+LL | fn hello(self_: Invariant<'_>) -> impl Sized + use<'_> {}
+ | -- ^^^^^^^^^^^^^^^^^^^^
+ | |
+ | this lifetime was captured
+ |
+note: hidden type must only reference lifetimes captured by this impl trait
+ --> $DIR/rpitit-impl-captures-too-much.rs:6:39
+ |
+LL | fn hello(self_: Invariant<'_>) -> impl Sized + use<Self>;
+ | ^^^^^^^^^^^^^^^^^^^^^^
+ = note: hidden type inferred to be `impl Sized`
+
+error: aborting due to 1 previous error
+
diff --git a/tests/ui/impl-trait/precise-capturing/rpitit.rs b/tests/ui/impl-trait/precise-capturing/rpitit.rs
index feeeb1461e827..3f887e8e47f1c 100644
--- a/tests/ui/impl-trait/precise-capturing/rpitit.rs
+++ b/tests/ui/impl-trait/precise-capturing/rpitit.rs
@@ -1,19 +1,34 @@
-//@ known-bug: unknown
-
// RPITITs don't have variances in their GATs, so they always relate invariantly
// and act as if they capture all their args.
// To fix this soundly, we need to make sure that all the trait header args
// remain captured, since they affect trait selection.
-trait Foo<'a> {
- fn hello() -> impl PartialEq + use<Self>;
+#![feature(precise_capturing_in_traits)]
+
+fn eq_types<T>(_: T, _: T) {}
+
+trait TraitLt<'a: 'a> {
+ fn hello() -> impl Sized + use<Self>;
+ //~^ ERROR `impl Trait` captures lifetime parameter, but it is not mentioned in `use<...>` precise captures list
+}
+fn trait_lt<'a, 'b, T: for<'r> TraitLt<'r>> () {
+ eq_types(
+ //~^ ERROR lifetime may not live long enough
+ //~| ERROR lifetime may not live long enough
+ <T as TraitLt<'a>>::hello(),
+ <T as TraitLt<'b>>::hello(),
+ );
}
-fn test<'a, 'b, T: for<'r> Foo<'r>>() {
- PartialEq::eq(
- &<T as Foo<'a>>::hello(),
- &<T as Foo<'b>>::hello(),
+trait MethodLt {
+ fn hello<'a: 'a>() -> impl Sized + use<Self>;
+}
+fn method_lt<'a, 'b, T: MethodLt> () {
+ eq_types(
+ T::hello::<'a>(),
+ T::hello::<'b>(),
);
+ // Good!
}
fn main() {}
diff --git a/tests/ui/impl-trait/precise-capturing/rpitit.stderr b/tests/ui/impl-trait/precise-capturing/rpitit.stderr
index c162875f327cc..8c219bb04a278 100644
--- a/tests/ui/impl-trait/precise-capturing/rpitit.stderr
+++ b/tests/ui/impl-trait/precise-capturing/rpitit.stderr
@@ -1,47 +1,40 @@
-error: `use<...>` precise capturing syntax is currently not allowed in return-position `impl Trait` in traits
- --> $DIR/rpitit.rs:9:36
- |
-LL | fn hello() -> impl PartialEq + use<Self>;
- | ^^^^^^^^^
- |
- = note: currently, return-position `impl Trait` in traits and trait implementations capture all lifetimes in scope
- = note: see issue #130044 <https://github.com/rust-lang/rust/issues/130044> for more information
- = help: add `#![feature(precise_capturing_in_traits)]` to the crate attributes to enable
- = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
-
error: `impl Trait` captures lifetime parameter, but it is not mentioned in `use<...>` precise captures list
- --> $DIR/rpitit.rs:9:19
+ --> $DIR/rpitit.rs:11:19
|
-LL | trait Foo<'a> {
- | -- this lifetime parameter is captured
-LL | fn hello() -> impl PartialEq + use<Self>;
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^ lifetime captured due to being mentioned in the bounds of the `impl Trait`
+LL | trait TraitLt<'a: 'a> {
+ | -- this lifetime parameter is captured
+LL | fn hello() -> impl Sized + use<Self>;
+ | ^^^^^^^^^^^^^^^^^^^^^^ lifetime captured due to being mentioned in the bounds of the `impl Trait`
error: lifetime may not live long enough
- --> $DIR/rpitit.rs:13:5
+ --> $DIR/rpitit.rs:15:5
|
-LL | fn test<'a, 'b, T: for<'r> Foo<'r>>() {
- | -- -- lifetime `'b` defined here
- | |
- | lifetime `'a` defined here
-LL | / PartialEq::eq(
-LL | | &<T as Foo<'a>>::hello(),
-LL | | &<T as Foo<'b>>::hello(),
+LL | fn trait_lt<'a, 'b, T: for<'r> TraitLt<'r>> () {
+ | -- -- lifetime `'b` defined here
+ | |
+ | lifetime `'a` defined here
+LL | / eq_types(
+LL | |
+LL | |
+LL | | <T as TraitLt<'a>>::hello(),
+LL | | <T as TraitLt<'b>>::hello(),
LL | | );
| |_____^ argument requires that `'a` must outlive `'b`
|
= help: consider adding the following bound: `'a: 'b`
error: lifetime may not live long enough
- --> $DIR/rpitit.rs:13:5
+ --> $DIR/rpitit.rs:15:5
|
-LL | fn test<'a, 'b, T: for<'r> Foo<'r>>() {
- | -- -- lifetime `'b` defined here
- | |
- | lifetime `'a` defined here
-LL | / PartialEq::eq(
-LL | | &<T as Foo<'a>>::hello(),
-LL | | &<T as Foo<'b>>::hello(),
+LL | fn trait_lt<'a, 'b, T: for<'r> TraitLt<'r>> () {
+ | -- -- lifetime `'b` defined here
+ | |
+ | lifetime `'a` defined here
+LL | / eq_types(
+LL | |
+LL | |
+LL | | <T as TraitLt<'a>>::hello(),
+LL | | <T as TraitLt<'b>>::hello(),
LL | | );
| |_____^ argument requires that `'b` must outlive `'a`
|
@@ -49,5 +42,5 @@ LL | | );
help: `'a` and `'b` must be the same: replace one with the other
-error: aborting due to 4 previous errors
+error: aborting due to 3 previous errors
diff --git a/tests/ui/impl-trait/precise-capturing/self-capture.rs b/tests/ui/impl-trait/precise-capturing/self-capture.rs
index a61a7f06edc1d..15985da50b55e 100644
--- a/tests/ui/impl-trait/precise-capturing/self-capture.rs
+++ b/tests/ui/impl-trait/precise-capturing/self-capture.rs
@@ -1,6 +1,9 @@
+//@ check-pass
+
+#![feature(precise_capturing_in_traits)]
+
trait Foo {
fn bar<'a>() -> impl Sized + use<Self>;
- //~^ ERROR `use<...>` precise capturing syntax is currently not allowed in return-position `impl Trait` in traits
}
fn main() {}
diff --git a/tests/ui/impl-trait/precise-capturing/self-capture.stderr b/tests/ui/impl-trait/precise-capturing/self-capture.stderr
deleted file mode 100644
index 45ebc429d88a7..0000000000000
--- a/tests/ui/impl-trait/precise-capturing/self-capture.stderr
+++ /dev/null
@@ -1,13 +0,0 @@
-error: `use<...>` precise capturing syntax is currently not allowed in return-position `impl Trait` in traits
- --> $DIR/self-capture.rs:2:34
- |
-LL | fn bar<'a>() -> impl Sized + use<Self>;
- | ^^^^^^^^^
- |
- = note: currently, return-position `impl Trait` in traits and trait implementations capture all lifetimes in scope
- = note: see issue #130044 <https://github.com/rust-lang/rust/issues/130044> for more information
- = help: add `#![feature(precise_capturing_in_traits)]` to the crate attributes to enable
- = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
-
-error: aborting due to 1 previous error
-
From 36076ecdc726c4e1104e70df2d142f39501a4f48 Mon Sep 17 00:00:00 2001
From: Michael Goulet <michael@errs.io>
Date: Sun, 29 Sep 2024 13:49:32 -0400
Subject: [PATCH 3/4] Clarify implicit captures for RPITIT
---
compiler/rustc_hir_analysis/messages.ftl | 3 +++
.../rustc_hir_analysis/src/check/check.rs | 25 ++++++++++++-------
.../src/errors/precise_captures.rs | 9 +++++++
.../precise-capturing/rpitit.stderr | 4 +--
4 files changed, 30 insertions(+), 11 deletions(-)
diff --git a/compiler/rustc_hir_analysis/messages.ftl b/compiler/rustc_hir_analysis/messages.ftl
index c73826c489f96..a80dc87c62242 100644
--- a/compiler/rustc_hir_analysis/messages.ftl
+++ b/compiler/rustc_hir_analysis/messages.ftl
@@ -259,6 +259,9 @@ hir_analysis_late_bound_lifetime_in_apit = `impl Trait` can only mention lifetim
hir_analysis_late_bound_type_in_apit = `impl Trait` can only mention type parameters from an fn or impl
.label = type parameter declared here
+hir_analysis_lifetime_implicitly_captured = `impl Trait` captures lifetime parameter, but it is not mentioned in `use<...>` precise captures list
+ .param_label = all lifetime parameters originating from a trait are captured implicitly
+
hir_analysis_lifetime_must_be_first = lifetime parameter `{$name}` must be listed before non-lifetime parameters
.label = move the lifetime before this parameter
diff --git a/compiler/rustc_hir_analysis/src/check/check.rs b/compiler/rustc_hir_analysis/src/check/check.rs
index eb62ff86c7179..d0063b449f894 100644
--- a/compiler/rustc_hir_analysis/src/check/check.rs
+++ b/compiler/rustc_hir_analysis/src/check/check.rs
@@ -589,15 +589,22 @@ fn check_opaque_precise_captures<'tcx>(tcx: TyCtxt<'tcx>, opaque_def_id: LocalDe
param_span: tcx.def_span(def_id),
});
} else {
- // If the `use_span` is actually just the param itself, then we must
- // have not duplicated the lifetime but captured the original.
- // The "effective" `use_span` will be the span of the opaque itself,
- // and the param span will be the def span of the param.
- tcx.dcx().emit_err(errors::LifetimeNotCaptured {
- opaque_span,
- use_span: opaque_span,
- param_span: use_span,
- });
+ if tcx.def_kind(tcx.parent(param.def_id)) == DefKind::Trait {
+ tcx.dcx().emit_err(errors::LifetimeImplicitlyCaptured {
+ opaque_span,
+ param_span: tcx.def_span(param.def_id),
+ });
+ } else {
+ // If the `use_span` is actually just the param itself, then we must
+ // have not duplicated the lifetime but captured the original.
+ // The "effective" `use_span` will be the span of the opaque itself,
+ // and the param span will be the def span of the param.
+ tcx.dcx().emit_err(errors::LifetimeNotCaptured {
+ opaque_span,
+ use_span: opaque_span,
+ param_span: use_span,
+ });
+ }
}
continue;
}
diff --git a/compiler/rustc_hir_analysis/src/errors/precise_captures.rs b/compiler/rustc_hir_analysis/src/errors/precise_captures.rs
index b6cffb90805b3..8a83866b7fa46 100644
--- a/compiler/rustc_hir_analysis/src/errors/precise_captures.rs
+++ b/compiler/rustc_hir_analysis/src/errors/precise_captures.rs
@@ -34,6 +34,15 @@ pub(crate) struct LifetimeNotCaptured {
pub opaque_span: Span,
}
+#[derive(Diagnostic)]
+#[diag(hir_analysis_lifetime_implicitly_captured)]
+pub(crate) struct LifetimeImplicitlyCaptured {
+ #[primary_span]
+ pub opaque_span: Span,
+ #[label(hir_analysis_param_label)]
+ pub param_span: Span,
+}
+
#[derive(Diagnostic)]
#[diag(hir_analysis_bad_precise_capture)]
pub(crate) struct BadPreciseCapture {
diff --git a/tests/ui/impl-trait/precise-capturing/rpitit.stderr b/tests/ui/impl-trait/precise-capturing/rpitit.stderr
index 8c219bb04a278..498eae54a1c68 100644
--- a/tests/ui/impl-trait/precise-capturing/rpitit.stderr
+++ b/tests/ui/impl-trait/precise-capturing/rpitit.stderr
@@ -2,9 +2,9 @@ error: `impl Trait` captures lifetime parameter, but it is not mentioned in `use
--> $DIR/rpitit.rs:11:19
|
LL | trait TraitLt<'a: 'a> {
- | -- this lifetime parameter is captured
+ | -- all lifetime parameters originating from a trait are captured implicitly
LL | fn hello() -> impl Sized + use<Self>;
- | ^^^^^^^^^^^^^^^^^^^^^^ lifetime captured due to being mentioned in the bounds of the `impl Trait`
+ | ^^^^^^^^^^^^^^^^^^^^^^
error: lifetime may not live long enough
--> $DIR/rpitit.rs:15:5
From 322c4bdac595e7689dcf08b847d0bd4d82a4bad9 Mon Sep 17 00:00:00 2001
From: Michael Goulet <michael@errs.io>
Date: Sun, 29 Sep 2024 13:49:53 -0400
Subject: [PATCH 4/4] Don't fire refinement lint if there are errors
---
.../rustc_hir_analysis/src/check/compare_impl_item/refine.rs | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/compiler/rustc_hir_analysis/src/check/compare_impl_item/refine.rs b/compiler/rustc_hir_analysis/src/check/compare_impl_item/refine.rs
index 80334c6efe7d6..2d6b9813271e2 100644
--- a/compiler/rustc_hir_analysis/src/check/compare_impl_item/refine.rs
+++ b/compiler/rustc_hir_analysis/src/check/compare_impl_item/refine.rs
@@ -64,6 +64,10 @@ pub(super) fn check_refining_return_position_impl_trait_in_trait<'tcx>(
return;
};
+ if hidden_tys.items().any(|(_, &ty)| ty.skip_binder().references_error()) {
+ return;
+ }
+
let mut collector = ImplTraitInTraitCollector { tcx, types: FxIndexSet::default() };
trait_m_sig.visit_with(&mut collector);