mikros/rust
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Rollup merge of #132209 - compiler-errors:modifiers, r=fmease

Browse Source 
Fix validation when lowering `?` trait bounds

Pass the unlowered (`rustc_hir`) polarity to `lower_poly_trait_ref`.

This allows us to actually *validate* that generic args are actually valid on `?Trait` paths. This actually regressed in #113671 because that PR changed the behavior where we were inadvertently re-lowering paths as `BoundPolarity::Positive`, which was also coincidentally the only place we were enforcing the generics on `?Trait` paths were correct.
This commit is contained in:
Jubilee 2024-10-31 17:50:40 -07:00 committed by GitHub
commit e31988cfc9
No known key found for this signature in database
GPG Key ID: B5690EEEBB952194
13 changed files with 119 additions and 58 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
compiler/rustc_hir_analysis/src/hir_ty_lowering/bounds.rs
View File

@ -168,12 +168,6 @@ pub(crate) fn lower_bounds<'hir, I: IntoIterator<Item = &'hir hir::GenericBound<
match hir_bound {
hir::GenericBound::Trait(poly_trait_ref) => {
let hir::TraitBoundModifiers { constness, polarity } = poly_trait_ref.modifiers;
let polarity = match polarity {
rustc_ast::BoundPolarity::Positive => ty::PredicatePolarity::Positive,
rustc_ast::BoundPolarity::Negative(_) => ty::PredicatePolarity::Negative,
rustc_ast::BoundPolarity::Maybe(_) => continue,
};
let _ = self.lower_poly_trait_ref(
&poly_trait_ref.trait_ref,
poly_trait_ref.span,

2
compiler/rustc_hir_analysis/src/hir_ty_lowering/dyn_compatibility.rs
View File

@ -51,7 +51,7 @@ pub(super) fn lower_trait_object_ty(
&trait_bound.trait_ref,
trait_bound.span,
hir::BoundConstness::Never,
ty::PredicatePolarity::Positive,
hir::BoundPolarity::Positive,
dummy_self,
&mut bounds,
PredicateFilter::SelfOnly,

47
compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs
View File

@ -668,7 +668,7 @@ pub(crate) fn lower_poly_trait_ref(
trait_ref: &hir::TraitRef<'tcx>,
span: Span,
constness: hir::BoundConstness,
polarity: ty::PredicatePolarity,
polarity: hir::BoundPolarity,
self_ty: Ty<'tcx>,
bounds: &mut Bounds<'tcx>,
predicate_filter: PredicateFilter,
@ -690,15 +690,6 @@ pub(crate) fn lower_poly_trait_ref(
Some(self_ty),
);
if let hir::BoundConstness::Always(span) | hir::BoundConstness::Maybe(span) = constness
&& !self.tcx().is_const_trait(trait_def_id)
{
self.dcx().emit_err(crate::errors::ConstBoundForNonConstTrait {
span,
modifier: constness.as_str(),
});
}
let tcx = self.tcx();
let bound_vars = tcx.late_bound_vars(trait_ref.hir_ref_id);
debug!(?bound_vars);
@ -708,6 +699,36 @@ pub(crate) fn lower_poly_trait_ref(
bound_vars,
);
let polarity = match polarity {
rustc_ast::BoundPolarity::Positive => ty::PredicatePolarity::Positive,
rustc_ast::BoundPolarity::Negative(_) => ty::PredicatePolarity::Negative,
rustc_ast::BoundPolarity::Maybe(_) => {
// Validate associated type at least. We may want to reject these
// outright in the future...
for constraint in trait_segment.args().constraints {
let _ = self.lower_assoc_item_constraint(
trait_ref.hir_ref_id,
poly_trait_ref,
constraint,
&mut Default::default(),
&mut Default::default(),
constraint.span,
predicate_filter,
);
}
return arg_count;
}
};
if let hir::BoundConstness::Always(span) | hir::BoundConstness::Maybe(span) = constness
&& !self.tcx().is_const_trait(trait_def_id)
{
self.dcx().emit_err(crate::errors::ConstBoundForNonConstTrait {
span,
modifier: constness.as_str(),
});
}
match predicate_filter {
PredicateFilter::All
| PredicateFilter::SelfOnly
@ -763,11 +784,11 @@ pub(crate) fn lower_poly_trait_ref(
// since we should have emitted an error for them earlier, and they
// would not be well-formed!
if polarity != ty::PredicatePolarity::Positive {
assert!(
self.dcx().has_errors().is_some(),
self.dcx().span_delayed_bug(
constraint.span,
"negative trait bounds should not have assoc item constraints",
);
continue;
break;
}
// Specify type to assert that error was already reported in `Err` case.

2
tests/ui/impl-trait/precise-capturing/bound-modifiers.rs
View File

@ -3,8 +3,6 @@
fn polarity() -> impl Sized + ?use<> {}
//~^ ERROR expected identifier, found keyword `use`
//~| ERROR cannot find trait `r#use` in this scope
//~| WARN relaxing a default bound only does something for `?Sized`
//~| WARN relaxing a default bound only does something for `?Sized`
fn asyncness() -> impl Sized + async use<> {}
//~^ ERROR expected identifier, found keyword `use`

32
tests/ui/impl-trait/precise-capturing/bound-modifiers.stderr
View File

@ -5,19 +5,19 @@ LL | fn polarity() -> impl Sized + ?use<> {}
| ^^^ expected identifier, found keyword
error: expected identifier, found keyword `use`
--> $DIR/bound-modifiers.rs:9:38
--> $DIR/bound-modifiers.rs:7:38
|
LL | fn asyncness() -> impl Sized + async use<> {}
| ^^^ expected identifier, found keyword
error: expected identifier, found keyword `use`
--> $DIR/bound-modifiers.rs:14:38
--> $DIR/bound-modifiers.rs:12:38
|
LL | fn constness() -> impl Sized + const use<> {}
| ^^^ expected identifier, found keyword
error: expected identifier, found keyword `use`
--> $DIR/bound-modifiers.rs:19:37
--> $DIR/bound-modifiers.rs:17:37
|
LL | fn binder() -> impl Sized + for<'a> use<> {}
| ^^^ expected identifier, found keyword
@ -29,25 +29,25 @@ LL | fn polarity() -> impl Sized + ?use<> {}
| ^^^ not found in this scope
error[E0405]: cannot find trait `r#use` in this scope
--> $DIR/bound-modifiers.rs:9:38
--> $DIR/bound-modifiers.rs:7:38
|
LL | fn asyncness() -> impl Sized + async use<> {}
| ^^^ not found in this scope
error[E0405]: cannot find trait `r#use` in this scope
--> $DIR/bound-modifiers.rs:14:38
--> $DIR/bound-modifiers.rs:12:38
|
LL | fn constness() -> impl Sized + const use<> {}
| ^^^ not found in this scope
error[E0405]: cannot find trait `r#use` in this scope
--> $DIR/bound-modifiers.rs:19:37
--> $DIR/bound-modifiers.rs:17:37
|
LL | fn binder() -> impl Sized + for<'a> use<> {}
| ^^^ not found in this scope
error[E0658]: async closures are unstable
--> $DIR/bound-modifiers.rs:9:32
--> $DIR/bound-modifiers.rs:7:32
|
LL | fn asyncness() -> impl Sized + async use<> {}
| ^^^^^
@ -58,7 +58,7 @@ LL | fn asyncness() -> impl Sized + async use<> {}
= help: to use an async block, remove the `||`: `async {`
error[E0658]: const trait impls are experimental
--> $DIR/bound-modifiers.rs:14:32
--> $DIR/bound-modifiers.rs:12:32
|
LL | fn constness() -> impl Sized + const use<> {}
| ^^^^^
@ -67,21 +67,7 @@ LL | fn constness() -> impl Sized + const use<> {}
= help: add `#![feature(const_trait_impl)]` to the crate attributes to enable
= note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
warning: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
--> $DIR/bound-modifiers.rs:3:31
|
LL | fn polarity() -> impl Sized + ?use<> {}
| ^^^^^^
warning: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
--> $DIR/bound-modifiers.rs:3:31
|
LL | fn polarity() -> impl Sized + ?use<> {}
| ^^^^^^
|
= note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
error: aborting due to 10 previous errors; 2 warnings emitted
error: aborting due to 10 previous errors
Some errors have detailed explanations: E0405, E0658.
For more information about an error, try `rustc --explain E0405`.

3
tests/ui/issues/issue-37534.rs
View File

@ -1,6 +1,5 @@
struct Foo<T: ?Hash> {}
//~^ ERROR expected trait, found derive macro `Hash`
//~^^ ERROR parameter `T` is never used
//~^^^ WARN relaxing a default bound only does something for `?Sized`
//~| WARN relaxing a default bound only does something for `?Sized`
fn main() {}

13
tests/ui/issues/issue-37534.stderr
View File

@ -15,15 +15,6 @@ warning: relaxing a default bound only does something for `?Sized`; all other tr
LL | struct Foo<T: ?Hash> {}
| ^^^^^
error[E0392]: type parameter `T` is never used
--> $DIR/issue-37534.rs:1:12
|
LL | struct Foo<T: ?Hash> {}
| ^ unused type parameter
|
= help: consider removing `T`, referring to it in a field, or using a marker such as `PhantomData`
error: aborting due to 1 previous error; 1 warning emitted
error: aborting due to 2 previous errors; 1 warning emitted
Some errors have detailed explanations: E0392, E0404.
For more information about an error, try `rustc --explain E0392`.
For more information about this error, try `rustc --explain E0404`.

4
tests/ui/trait-bounds/maybe-bound-generics-deny.rs Normal file
View File

@ -0,0 +1,4 @@
fn uwu<T: ?Sized<i32>>() {}
//~^ ERROR trait takes 0 generic arguments but 1 generic argument was supplied
fn main() {}

11
tests/ui/trait-bounds/maybe-bound-generics-deny.stderr Normal file
View File

@ -0,0 +1,11 @@
error[E0107]: trait takes 0 generic arguments but 1 generic argument was supplied
--> $DIR/maybe-bound-generics-deny.rs:1:12
|
LL | fn uwu<T: ?Sized<i32>>() {}
| ^^^^^----- help: remove the unnecessary generics
| |
| expected 0 generic arguments
error: aborting due to 1 previous error
For more information about this error, try `rustc --explain E0107`.

7
tests/ui/trait-bounds/maybe-bound-has-path-args.rs Normal file
View File

@ -0,0 +1,7 @@
trait Trait {}
fn test<T: ?self::<i32>::Trait>() {}
//~^ ERROR type arguments are not allowed on this type
//~| WARN relaxing a default bound only does something for `?Sized`
fn main() {}

17
tests/ui/trait-bounds/maybe-bound-has-path-args.stderr Normal file
View File

@ -0,0 +1,17 @@
warning: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
--> $DIR/maybe-bound-has-path-args.rs:3:12
|
LL | fn test<T: ?self::<i32>::Trait>() {}
| ^^^^^^^^^^^^^^^^^^^
error[E0109]: type arguments are not allowed on this type
--> $DIR/maybe-bound-has-path-args.rs:3:20
|
LL | fn test<T: ?self::<i32>::Trait>() {}
| ---- ^^^ type argument not allowed
| |
| not allowed on this type
error: aborting due to 1 previous error; 1 warning emitted
For more information about this error, try `rustc --explain E0109`.

12
tests/ui/trait-bounds/maybe-bound-with-assoc.rs Normal file
View File

@ -0,0 +1,12 @@
trait HasAssoc {
type Assoc;
}
fn hasassoc<T: ?HasAssoc<Assoc = ()>>() {}
//~^ WARN relaxing a default bound
trait NoAssoc {}
fn noassoc<T: ?NoAssoc<Missing = ()>>() {}
//~^ WARN relaxing a default bound
//~| ERROR associated type `Missing` not found for `NoAssoc`
fn main() {}

21
tests/ui/trait-bounds/maybe-bound-with-assoc.stderr Normal file
View File

@ -0,0 +1,21 @@
warning: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
--> $DIR/maybe-bound-with-assoc.rs:4:16
|
LL | fn hasassoc<T: ?HasAssoc<Assoc = ()>>() {}
| ^^^^^^^^^^^^^^^^^^^^^
warning: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
--> $DIR/maybe-bound-with-assoc.rs:8:15
|
LL | fn noassoc<T: ?NoAssoc<Missing = ()>>() {}
| ^^^^^^^^^^^^^^^^^^^^^^
error[E0220]: associated type `Missing` not found for `NoAssoc`
--> $DIR/maybe-bound-with-assoc.rs:8:24
|
LL | fn noassoc<T: ?NoAssoc<Missing = ()>>() {}
| ^^^^^^^ associated type `Missing` not found
error: aborting due to 1 previous error; 2 warnings emitted
For more information about this error, try `rustc --explain E0220`.