diff --git a/compiler/rustc_ast_lowering/messages.ftl b/compiler/rustc_ast_lowering/messages.ftl
index c6472fd45fa98..370b15d2871a9 100644
--- a/compiler/rustc_ast_lowering/messages.ftl
+++ b/compiler/rustc_ast_lowering/messages.ftl
@@ -127,9 +127,6 @@ ast_lowering_misplaced_impl_trait =
`impl Trait` is not allowed in {$position}
.note = `impl Trait` is only allowed in arguments and return types of functions and methods
-ast_lowering_misplaced_relax_trait_bound =
- `?Trait` bounds are only permitted at the point where a type parameter is declared
-
ast_lowering_never_pattern_with_body =
a never pattern is always unreachable
.label = this will never be executed
diff --git a/compiler/rustc_ast_lowering/src/errors.rs b/compiler/rustc_ast_lowering/src/errors.rs
index b444324ef9143..83f3a976e83f7 100644
--- a/compiler/rustc_ast_lowering/src/errors.rs
+++ b/compiler/rustc_ast_lowering/src/errors.rs
@@ -324,13 +324,6 @@ pub(crate) struct MisplacedDoubleDot {
pub span: Span,
}
-#[derive(Diagnostic)]
-#[diag(ast_lowering_misplaced_relax_trait_bound)]
-pub(crate) struct MisplacedRelaxTraitBound {
- #[primary_span]
- pub span: Span,
-}
-
#[derive(Diagnostic)]
#[diag(ast_lowering_match_arm_with_no_body)]
pub(crate) struct MatchArmWithNoBody {
diff --git a/compiler/rustc_ast_lowering/src/item.rs b/compiler/rustc_ast_lowering/src/item.rs
index 8acb510577302..4df7697bcfb32 100644
--- a/compiler/rustc_ast_lowering/src/item.rs
+++ b/compiler/rustc_ast_lowering/src/item.rs
@@ -15,14 +15,11 @@ use smallvec::{SmallVec, smallvec};
use thin_vec::ThinVec;
use tracing::instrument;
-use super::errors::{
- InvalidAbi, InvalidAbiSuggestion, MisplacedRelaxTraitBound, TupleStructWithDefault,
- UnionWithDefault,
-};
+use super::errors::{InvalidAbi, InvalidAbiSuggestion, TupleStructWithDefault, UnionWithDefault};
use super::stability::{enabled_names, gate_unstable_abi};
use super::{
AstOwner, FnDeclKind, ImplTraitContext, ImplTraitPosition, LoweringContext, ParamMode,
- ResolverAstLoweringExt,
+ RelaxedBoundForbiddenReason, RelaxedBoundPolicy, ResolverAstLoweringExt,
};
pub(super) struct ItemLowerer<'a, 'hir> {
@@ -427,6 +424,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
|this| {
let bounds = this.lower_param_bounds(
bounds,
+ RelaxedBoundPolicy::Forbidden(RelaxedBoundForbiddenReason::SuperTrait),
ImplTraitContext::Disallowed(ImplTraitPosition::Bound),
);
let items = this.arena.alloc_from_iter(
@@ -447,6 +445,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
|this| {
this.lower_param_bounds(
bounds,
+ RelaxedBoundPolicy::Allowed,
ImplTraitContext::Disallowed(ImplTraitPosition::Bound),
)
},
@@ -938,6 +937,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
hir::TraitItemKind::Type(
this.lower_param_bounds(
bounds,
+ RelaxedBoundPolicy::Allowed,
ImplTraitContext::Disallowed(ImplTraitPosition::Generic),
),
ty,
@@ -1723,61 +1723,6 @@ impl<'hir> LoweringContext<'_, 'hir> {
assert!(self.impl_trait_defs.is_empty());
assert!(self.impl_trait_bounds.is_empty());
- // Error if `?Trait` bounds in where clauses don't refer directly to type parameters.
- // Note: we used to clone these bounds directly onto the type parameter (and avoid lowering
- // these into hir when we lower thee where clauses), but this makes it quite difficult to
- // keep track of the Span info. Now, `<dyn HirTyLowerer>::add_implicit_sized_bound`
- // checks both param bounds and where clauses for `?Sized`.
- for pred in &generics.where_clause.predicates {
- let WherePredicateKind::BoundPredicate(bound_pred) = &pred.kind else {
- continue;
- };
- let compute_is_param = || {
- // Check if the where clause type is a plain type parameter.
- match self
- .resolver
- .get_partial_res(bound_pred.bounded_ty.id)
- .and_then(|r| r.full_res())
- {
- Some(Res::Def(DefKind::TyParam, def_id))
- if bound_pred.bound_generic_params.is_empty() =>
- {
- generics
- .params
- .iter()
- .any(|p| def_id == self.local_def_id(p.id).to_def_id())
- }
- // Either the `bounded_ty` is not a plain type parameter, or
- // it's not found in the generic type parameters list.
- _ => false,
- }
- };
- // We only need to compute this once per `WherePredicate`, but don't
- // need to compute this at all unless there is a Maybe bound.
- let mut is_param: Option<bool> = None;
- for bound in &bound_pred.bounds {
- if !matches!(
- *bound,
- GenericBound::Trait(PolyTraitRef {
- modifiers: TraitBoundModifiers { polarity: BoundPolarity::Maybe(_), .. },
- ..
- })
- ) {
- continue;
- }
- let is_param = *is_param.get_or_insert_with(compute_is_param);
- if !is_param && !self.tcx.features().more_maybe_bounds() {
- self.tcx
- .sess
- .create_feature_err(
- MisplacedRelaxTraitBound { span: bound.span() },
- sym::more_maybe_bounds,
- )
- .emit();
- }
- }
- }
-
let mut predicates: SmallVec<[hir::WherePredicate<'hir>; 4]> = SmallVec::new();
predicates.extend(generics.params.iter().filter_map(|param| {
self.lower_generic_bound_predicate(
@@ -1787,6 +1732,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
¶m.bounds,
param.colon_span,
generics.span,
+ RelaxedBoundPolicy::Allowed,
itctx,
PredicateOrigin::GenericParam,
)
@@ -1796,7 +1742,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
.where_clause
.predicates
.iter()
- .map(|predicate| self.lower_where_predicate(predicate)),
+ .map(|predicate| self.lower_where_predicate(predicate, &generics.params)),
);
let mut params: SmallVec<[hir::GenericParam<'hir>; 4]> = self
@@ -1873,6 +1819,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
bounds: &[GenericBound],
colon_span: Option<Span>,
parent_span: Span,
+ rbp: RelaxedBoundPolicy<'_>,
itctx: ImplTraitContext,
origin: PredicateOrigin,
) -> Option<hir::WherePredicate<'hir>> {
@@ -1881,7 +1828,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
return None;
}
- let bounds = self.lower_param_bounds(bounds, itctx);
+ let bounds = self.lower_param_bounds(bounds, rbp, itctx);
let param_span = ident.span;
@@ -1933,7 +1880,11 @@ impl<'hir> LoweringContext<'_, 'hir> {
Some(hir::WherePredicate { hir_id, span, kind })
}
- fn lower_where_predicate(&mut self, pred: &WherePredicate) -> hir::WherePredicate<'hir> {
+ fn lower_where_predicate(
+ &mut self,
+ pred: &WherePredicate,
+ params: &[ast::GenericParam],
+ ) -> hir::WherePredicate<'hir> {
let hir_id = self.lower_node_id(pred.id);
let span = self.lower_span(pred.span);
self.lower_attrs(hir_id, &pred.attrs, span);
@@ -1942,17 +1893,29 @@ impl<'hir> LoweringContext<'_, 'hir> {
bound_generic_params,
bounded_ty,
bounds,
- }) => hir::WherePredicateKind::BoundPredicate(hir::WhereBoundPredicate {
- bound_generic_params: self
- .lower_generic_params(bound_generic_params, hir::GenericParamSource::Binder),
- bounded_ty: self
- .lower_ty(bounded_ty, ImplTraitContext::Disallowed(ImplTraitPosition::Bound)),
- bounds: self.lower_param_bounds(
- bounds,
- ImplTraitContext::Disallowed(ImplTraitPosition::Bound),
- ),
- origin: PredicateOrigin::WhereClause,
- }),
+ }) => {
+ let rbp = if bound_generic_params.is_empty() {
+ RelaxedBoundPolicy::AllowedIfOnTyParam(bounded_ty.id, params)
+ } else {
+ RelaxedBoundPolicy::Forbidden(RelaxedBoundForbiddenReason::LateBoundVarsInScope)
+ };
+ hir::WherePredicateKind::BoundPredicate(hir::WhereBoundPredicate {
+ bound_generic_params: self.lower_generic_params(
+ bound_generic_params,
+ hir::GenericParamSource::Binder,
+ ),
+ bounded_ty: self.lower_ty(
+ bounded_ty,
+ ImplTraitContext::Disallowed(ImplTraitPosition::Bound),
+ ),
+ bounds: self.lower_param_bounds(
+ bounds,
+ rbp,
+ ImplTraitContext::Disallowed(ImplTraitPosition::Bound),
+ ),
+ origin: PredicateOrigin::WhereClause,
+ })
+ }
WherePredicateKind::RegionPredicate(WhereRegionPredicate { lifetime, bounds }) => {
hir::WherePredicateKind::RegionPredicate(hir::WhereRegionPredicate {
lifetime: self.lower_lifetime(
@@ -1962,6 +1925,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
),
bounds: self.lower_param_bounds(
bounds,
+ RelaxedBoundPolicy::Allowed,
ImplTraitContext::Disallowed(ImplTraitPosition::Bound),
),
in_where_clause: true,
diff --git a/compiler/rustc_ast_lowering/src/lib.rs b/compiler/rustc_ast_lowering/src/lib.rs
index 26d7c0cd6d38f..8faf96a6df2d1 100644
--- a/compiler/rustc_ast_lowering/src/lib.rs
+++ b/compiler/rustc_ast_lowering/src/lib.rs
@@ -53,14 +53,14 @@ use rustc_hir::def::{DefKind, LifetimeRes, Namespace, PartialRes, PerNS, Res};
use rustc_hir::def_id::{CRATE_DEF_ID, LOCAL_CRATE, LocalDefId};
use rustc_hir::lints::DelayedLint;
use rustc_hir::{
- self as hir, AngleBrackets, ConstArg, GenericArg, HirId, ItemLocalMap, LangItem,
- LifetimeSource, LifetimeSyntax, ParamName, TraitCandidate,
+ self as hir, AngleBrackets, ConstArg, GenericArg, HirId, ItemLocalMap, LifetimeSource,
+ LifetimeSyntax, ParamName, TraitCandidate,
};
use rustc_index::{Idx, IndexSlice, IndexVec};
use rustc_macros::extension;
use rustc_middle::span_bug;
use rustc_middle::ty::{ResolverAstLowering, TyCtxt};
-use rustc_session::parse::add_feature_diagnostics;
+use rustc_session::parse::{add_feature_diagnostics, feature_err};
use rustc_span::symbol::{Ident, Symbol, kw, sym};
use rustc_span::{DUMMY_SP, DesugaringKind, Span};
use smallvec::SmallVec;
@@ -276,6 +276,20 @@ impl ResolverAstLowering {
}
}
+#[derive(Clone, Copy, Debug)]
+enum RelaxedBoundPolicy<'a> {
+ Allowed,
+ AllowedIfOnTyParam(NodeId, &'a [ast::GenericParam]),
+ Forbidden(RelaxedBoundForbiddenReason),
+}
+
+#[derive(Clone, Copy, Debug)]
+enum RelaxedBoundForbiddenReason {
+ TraitObjectTy,
+ SuperTrait,
+ LateBoundVarsInScope,
+}
+
/// Context of `impl Trait` in code, which determines whether it is allowed in an HIR subtree,
/// and if so, what meaning it has.
#[derive(Debug, Copy, Clone, PartialEq, Eq)]
@@ -1079,10 +1093,9 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
&*self.arena.alloc(self.ty(constraint.span, hir::TyKind::Err(guar)));
hir::AssocItemConstraintKind::Equality { term: err_ty.into() }
} else {
- // Desugar `AssocTy: Bounds` into an assoc type binding where the
- // later desugars into a trait predicate.
- let bounds = self.lower_param_bounds(bounds, itctx);
-
+ // FIXME(#135229): These should be forbidden!
+ let bounds =
+ self.lower_param_bounds(bounds, RelaxedBoundPolicy::Allowed, itctx);
hir::AssocItemConstraintKind::Bound { bounds }
}
}
@@ -1210,6 +1223,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
trait_ref: TraitRef { path: path.clone(), ref_id: t.id },
span: t.span,
},
+ RelaxedBoundPolicy::Forbidden(RelaxedBoundForbiddenReason::TraitObjectTy),
itctx,
);
let bounds = this.arena.alloc_from_iter([bound]);
@@ -1265,7 +1279,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
parenthesized: hir::GenericArgsParentheses::No,
span_ext: span,
});
- let path = self.make_lang_item_qpath(LangItem::Pin, span, Some(args));
+ let path = self.make_lang_item_qpath(hir::LangItem::Pin, span, Some(args));
hir::TyKind::Path(path)
}
TyKind::BareFn(f) => {
@@ -1326,7 +1340,13 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
// takes care of rejecting invalid modifier combinations and
// const trait bounds in trait object types.
GenericBound::Trait(ty) => {
- let trait_ref = this.lower_poly_trait_ref(ty, itctx);
+ let trait_ref = this.lower_poly_trait_ref(
+ ty,
+ RelaxedBoundPolicy::Forbidden(
+ RelaxedBoundForbiddenReason::TraitObjectTy,
+ ),
+ itctx,
+ );
Some(trait_ref)
}
GenericBound::Outlives(lifetime) => {
@@ -1381,9 +1401,9 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
}
path
}
- ImplTraitContext::InBinding => {
- hir::TyKind::TraitAscription(self.lower_param_bounds(bounds, itctx))
- }
+ ImplTraitContext::InBinding => hir::TyKind::TraitAscription(
+ self.lower_param_bounds(bounds, RelaxedBoundPolicy::Allowed, itctx),
+ ),
ImplTraitContext::FeatureGated(position, feature) => {
let guar = self
.tcx
@@ -1499,7 +1519,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
let opaque_ty_span = self.mark_span_with_reason(DesugaringKind::OpaqueTy, span, None);
self.lower_opaque_inner(opaque_ty_node_id, origin, opaque_ty_span, |this| {
- this.lower_param_bounds(bounds, itctx)
+ this.lower_param_bounds(bounds, RelaxedBoundPolicy::Allowed, itctx)
})
}
@@ -1793,10 +1813,13 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
fn lower_param_bound(
&mut self,
tpb: &GenericBound,
+ rbp: RelaxedBoundPolicy<'_>,
itctx: ImplTraitContext,
) -> hir::GenericBound<'hir> {
match tpb {
- GenericBound::Trait(p) => hir::GenericBound::Trait(self.lower_poly_trait_ref(p, itctx)),
+ GenericBound::Trait(p) => {
+ hir::GenericBound::Trait(self.lower_poly_trait_ref(p, rbp, itctx))
+ }
GenericBound::Outlives(lifetime) => hir::GenericBound::Outlives(self.lower_lifetime(
lifetime,
LifetimeSource::OutlivesBound,
@@ -2011,19 +2034,81 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
#[instrument(level = "debug", skip(self))]
fn lower_poly_trait_ref(
&mut self,
- p: &PolyTraitRef,
+ tr: &PolyTraitRef,
+ rbp: RelaxedBoundPolicy<'_>,
itctx: ImplTraitContext,
) -> hir::PolyTraitRef<'hir> {
+ let PolyTraitRef { ref bound_generic_params, modifiers, ref trait_ref, span } = *tr;
+
let bound_generic_params =
- self.lower_lifetime_binder(p.trait_ref.ref_id, &p.bound_generic_params);
- let trait_ref = self.lower_trait_ref(p.modifiers, &p.trait_ref, itctx);
- let modifiers = self.lower_trait_bound_modifiers(p.modifiers);
+ self.lower_lifetime_binder(trait_ref.ref_id, bound_generic_params);
+ let trait_ref = self.lower_trait_ref(modifiers, trait_ref, itctx);
+ let modifiers = self.lower_trait_bound_modifiers(modifiers);
+
+ if let ast::BoundPolarity::Maybe(_) = modifiers.polarity {
+ self.validate_relaxed_bound(trait_ref, span, rbp);
+ }
+
hir::PolyTraitRef {
bound_generic_params,
modifiers,
trait_ref,
- span: self.lower_span(p.span),
+ span: self.lower_span(span),
+ }
+ }
+
+ fn validate_relaxed_bound(
+ &self,
+ trait_ref: hir::TraitRef<'_>,
+ span: Span,
+ rbp: RelaxedBoundPolicy<'_>,
+ ) {
+ let err = |message| feature_err(&self.tcx.sess, sym::more_maybe_bounds, span, message);
+
+ match rbp {
+ RelaxedBoundPolicy::Allowed => return,
+ RelaxedBoundPolicy::AllowedIfOnTyParam(id, params) => {
+ if let Some(res) = self.resolver.get_partial_res(id).and_then(|r| r.full_res())
+ && let Res::Def(DefKind::TyParam, def_id) = res
+ && params.iter().any(|p| def_id == self.local_def_id(p.id).to_def_id())
+ {
+ return;
+ }
+ if self.tcx.features().more_maybe_bounds() {
+ return;
+ }
+ }
+ RelaxedBoundPolicy::Forbidden(reason) => {
+ if self.tcx.features().more_maybe_bounds() {
+ return;
+ }
+
+ match reason {
+ RelaxedBoundForbiddenReason::TraitObjectTy => {
+ err("relaxed bounds are not permitted in trait object types").emit();
+ return;
+ }
+ RelaxedBoundForbiddenReason::SuperTrait => {
+ let mut diag = err("relaxed bounds are not permitted in supertrait bounds");
+ if let Some(def_id) = trait_ref.trait_def_id()
+ && self.tcx.is_lang_item(def_id, hir::LangItem::Sized)
+ {
+ diag.note("traits are `?Sized` by default");
+ }
+ diag.emit();
+ return;
+ }
+ RelaxedBoundForbiddenReason::LateBoundVarsInScope => {}
+ };
+ }
}
+
+ err("this relaxed bound is not permitted here")
+ .with_note(
+ "in this context, relaxed bounds are only allowed on \
+ type parameters defined by the closest item",
+ )
+ .emit();
}
fn lower_mt(&mut self, mt: &MutTy, itctx: ImplTraitContext) -> hir::MutTy<'hir> {
@@ -2034,17 +2119,19 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
fn lower_param_bounds(
&mut self,
bounds: &[GenericBound],
+ rbp: RelaxedBoundPolicy<'_>,
itctx: ImplTraitContext,
) -> hir::GenericBounds<'hir> {
- self.arena.alloc_from_iter(self.lower_param_bounds_mut(bounds, itctx))
+ self.arena.alloc_from_iter(self.lower_param_bounds_mut(bounds, rbp, itctx))
}
fn lower_param_bounds_mut(
&mut self,
bounds: &[GenericBound],
+ rbp: RelaxedBoundPolicy<'_>,
itctx: ImplTraitContext,
) -> impl Iterator<Item = hir::GenericBound<'hir>> {
- bounds.iter().map(move |bound| self.lower_param_bound(bound, itctx))
+ bounds.iter().map(move |bound| self.lower_param_bound(bound, rbp, itctx))
}
#[instrument(level = "debug", skip(self), ret)]
@@ -2078,6 +2165,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
bounds,
/* colon_span */ None,
span,
+ RelaxedBoundPolicy::Allowed,
ImplTraitContext::Universal,
hir::PredicateOrigin::ImplTrait,
);
diff --git a/compiler/rustc_ast_passes/messages.ftl b/compiler/rustc_ast_passes/messages.ftl
index 4290f7b7edeb0..fb5a41f352853 100644
--- a/compiler/rustc_ast_passes/messages.ftl
+++ b/compiler/rustc_ast_passes/messages.ftl
@@ -212,11 +212,6 @@ ast_passes_nomangle_ascii = `#[no_mangle]` requires ASCII identifier
ast_passes_obsolete_auto = `impl Trait for .. {"{}"}` is an obsolete syntax
.help = use `auto trait Trait {"{}"}` instead
-ast_passes_optional_trait_object = `?Trait` is not permitted in trait object types
-
-ast_passes_optional_trait_supertrait = `?Trait` is not permitted in supertraits
- .note = traits are `?{$path_str}` by default
-
ast_passes_out_of_order_params = {$param_ord} parameters must be declared prior to {$max_param} parameters
.suggestion = reorder the parameters: lifetimes, then consts and types
diff --git a/compiler/rustc_ast_passes/src/ast_validation.rs b/compiler/rustc_ast_passes/src/ast_validation.rs
index da24825120376..62182fdb26fca 100644
--- a/compiler/rustc_ast_passes/src/ast_validation.rs
+++ b/compiler/rustc_ast_passes/src/ast_validation.rs
@@ -1373,29 +1373,6 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
match bound {
GenericBound::Trait(trait_ref) => {
match (ctxt, trait_ref.modifiers.constness, trait_ref.modifiers.polarity) {
- (BoundKind::SuperTraits, BoundConstness::Never, BoundPolarity::Maybe(_))
- if !self.features.more_maybe_bounds() =>
- {
- self.sess
- .create_feature_err(
- errors::OptionalTraitSupertrait {
- span: trait_ref.span,
- path_str: pprust::path_to_string(&trait_ref.trait_ref.path),
- },
- sym::more_maybe_bounds,
- )
- .emit();
- }
- (BoundKind::TraitObject, BoundConstness::Never, BoundPolarity::Maybe(_))
- if !self.features.more_maybe_bounds() =>
- {
- self.sess
- .create_feature_err(
- errors::OptionalTraitObject { span: trait_ref.span },
- sym::more_maybe_bounds,
- )
- .emit();
- }
(
BoundKind::TraitObject,
BoundConstness::Always(_),
diff --git a/compiler/rustc_ast_passes/src/errors.rs b/compiler/rustc_ast_passes/src/errors.rs
index d387a4a310ea0..2e0fac8ec0b30 100644
--- a/compiler/rustc_ast_passes/src/errors.rs
+++ b/compiler/rustc_ast_passes/src/errors.rs
@@ -566,22 +566,6 @@ pub(crate) struct NestedLifetimes {
pub span: Span,
}
-#[derive(Diagnostic)]
-#[diag(ast_passes_optional_trait_supertrait)]
-#[note]
-pub(crate) struct OptionalTraitSupertrait {
- #[primary_span]
- pub span: Span,
- pub path_str: String,
-}
-
-#[derive(Diagnostic)]
-#[diag(ast_passes_optional_trait_object)]
-pub(crate) struct OptionalTraitObject {
- #[primary_span]
- pub span: Span,
-}
-
#[derive(Diagnostic)]
#[diag(ast_passes_const_bound_trait_object)]
pub(crate) struct ConstBoundTraitObject {
diff --git a/compiler/rustc_error_codes/src/error_codes/E0203.md b/compiler/rustc_error_codes/src/error_codes/E0203.md
index 1edb519275f79..a4dceedbf1fd1 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0203.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0203.md
@@ -1,15 +1,15 @@
-Having multiple relaxed default bounds is unsupported.
+Having duplicate relaxed default bounds is unsupported.
Erroneous code example:
```compile_fail,E0203
-struct Bad<T: ?Sized + ?Send>{
- inner: T
+struct Bad<T: ?Sized + ?Sized>{
+ inner: T,
}
```
-Here the type `T` cannot have a relaxed bound for multiple default traits
-(`Sized` and `Send`). This can be fixed by only using one relaxed bound.
+Here the type parameter `T` cannot have duplicate relaxed bounds for default
+trait `Sized`. This can be fixed by only using one relaxed bound:
```
struct Good<T: ?Sized>{
diff --git a/compiler/rustc_hir_analysis/messages.ftl b/compiler/rustc_hir_analysis/messages.ftl
index 529d3578985ae..a2fd665f2a4fa 100644
--- a/compiler/rustc_hir_analysis/messages.ftl
+++ b/compiler/rustc_hir_analysis/messages.ftl
@@ -371,9 +371,6 @@ hir_analysis_missing_type_params =
*[other] parameters
} must be specified on the object type
-hir_analysis_multiple_relaxed_default_bounds =
- type parameter has more than one relaxed default bound, only one is supported
-
hir_analysis_must_be_name_of_associated_function = must be a name of an associated function
hir_analysis_must_implement_not_function = not a function
@@ -448,8 +445,6 @@ hir_analysis_parenthesized_fn_trait_expansion =
hir_analysis_placeholder_not_allowed_item_signatures = the placeholder `_` is not allowed within types on item signatures for {$kind}
.label = not allowed in type signatures
-hir_analysis_pointee_sized_trait_object = `PointeeSized` cannot be used with trait objects
-
hir_analysis_precise_capture_self_alias = `Self` can't be captured in `use<...>` precise captures list, since it is an alias
.label = `Self` is not a generic argument, but an alias to the type of the {$what}
diff --git a/compiler/rustc_hir_analysis/src/collect/predicates_of.rs b/compiler/rustc_hir_analysis/src/collect/predicates_of.rs
index a93e58b101fe5..70b6482273f59 100644
--- a/compiler/rustc_hir_analysis/src/collect/predicates_of.rs
+++ b/compiler/rustc_hir_analysis/src/collect/predicates_of.rs
@@ -266,20 +266,16 @@ fn gather_explicit_predicates_of(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::Gen
match predicate.kind {
hir::WherePredicateKind::BoundPredicate(bound_pred) => {
let ty = icx.lowerer().lower_ty_maybe_return_type_notation(bound_pred.bounded_ty);
-
let bound_vars = tcx.late_bound_vars(predicate.hir_id);
- // Keep the type around in a dummy predicate, in case of no bounds.
- // That way, `where Ty:` is not a complete noop (see #53696) and `Ty`
- // is still checked for WF.
+
+ // This is a `where Ty:` (sic!).
if bound_pred.bounds.is_empty() {
if let ty::Param(_) = ty.kind() {
- // This is a `where T:`, which can be in the HIR from the
- // transformation that moves `?Sized` to `T`'s declaration.
- // We can skip the predicate because type parameters are
- // trivially WF, but also we *should*, to avoid exposing
- // users who never wrote `where Type:,` themselves, to
- // compiler/tooling bugs from not handling WF predicates.
+ // We can skip the predicate because type parameters are trivially WF.
} else {
+ // Keep the type around in a dummy predicate. That way, it's not a complete
+ // noop (see #53696) and `Ty` is still checked for WF.
+
let span = bound_pred.bounded_ty.span;
let predicate = ty::Binder::bind_with_vars(
ty::ClauseKind::WellFormed(ty.into()),
diff --git a/compiler/rustc_hir_analysis/src/errors.rs b/compiler/rustc_hir_analysis/src/errors.rs
index c1c828392126f..9f2371b41b69b 100644
--- a/compiler/rustc_hir_analysis/src/errors.rs
+++ b/compiler/rustc_hir_analysis/src/errors.rs
@@ -278,13 +278,6 @@ pub(crate) struct CopyImplOnTypeWithDtor {
pub span: Span,
}
-#[derive(Diagnostic)]
-#[diag(hir_analysis_multiple_relaxed_default_bounds, code = E0203)]
-pub(crate) struct MultipleRelaxedDefaultBounds {
- #[primary_span]
- pub spans: Vec<Span>,
-}
-
#[derive(Diagnostic)]
#[diag(hir_analysis_copy_impl_on_non_adt, code = E0206)]
pub(crate) struct CopyImplOnNonAdt {
@@ -318,13 +311,6 @@ pub(crate) struct TraitObjectDeclaredWithNoTraits {
pub trait_alias_span: Option<Span>,
}
-#[derive(Diagnostic)]
-#[diag(hir_analysis_pointee_sized_trait_object)]
-pub(crate) struct PointeeSizedTraitObject {
- #[primary_span]
- pub span: Span,
-}
-
#[derive(Diagnostic)]
#[diag(hir_analysis_ambiguous_lifetime_bound, code = E0227)]
pub(crate) struct AmbiguousLifetimeBound {
diff --git a/compiler/rustc_hir_analysis/src/hir_ty_lowering/bounds.rs b/compiler/rustc_hir_analysis/src/hir_ty_lowering/bounds.rs
index d17986d45d2f2..161fbba9cde57 100644
--- a/compiler/rustc_hir_analysis/src/hir_ty_lowering/bounds.rs
+++ b/compiler/rustc_hir_analysis/src/hir_ty_lowering/bounds.rs
@@ -6,7 +6,7 @@ use rustc_errors::struct_span_code_err;
use rustc_hir as hir;
use rustc_hir::def::{DefKind, Res};
use rustc_hir::def_id::{CRATE_DEF_ID, DefId, LocalDefId};
-use rustc_hir::{AmbigArg, LangItem, PolyTraitRef};
+use rustc_hir::{AmbigArg, PolyTraitRef};
use rustc_middle::bug;
use rustc_middle::ty::{
self as ty, IsSuggestable, Ty, TyCtxt, TypeSuperVisitable, TypeVisitable, TypeVisitableExt,
@@ -85,17 +85,17 @@ fn search_bounds_for<'tcx>(
}
}
-fn collect_unbounds<'tcx>(
+fn collect_relaxed_bounds<'tcx>(
hir_bounds: &'tcx [hir::GenericBound<'tcx>],
self_ty_where_predicates: Option<(LocalDefId, &'tcx [hir::WherePredicate<'tcx>])>,
) -> SmallVec<[&'tcx PolyTraitRef<'tcx>; 1]> {
- let mut unbounds: SmallVec<[_; 1]> = SmallVec::new();
+ let mut relaxed_bounds: SmallVec<[_; 1]> = SmallVec::new();
search_bounds_for(hir_bounds, self_ty_where_predicates, |ptr| {
if matches!(ptr.modifiers.polarity, hir::BoundPolarity::Maybe(_)) {
- unbounds.push(ptr);
+ relaxed_bounds.push(ptr);
}
});
- unbounds
+ relaxed_bounds
}
fn collect_bounds<'a, 'tcx>(
@@ -124,13 +124,13 @@ fn collect_sizedness_bounds<'tcx>(
self_ty_where_predicates: Option<(LocalDefId, &'tcx [hir::WherePredicate<'tcx>])>,
span: Span,
) -> CollectedSizednessBounds {
- let sized_did = tcx.require_lang_item(LangItem::Sized, span);
+ let sized_did = tcx.require_lang_item(hir::LangItem::Sized, span);
let sized = collect_bounds(hir_bounds, self_ty_where_predicates, sized_did);
- let meta_sized_did = tcx.require_lang_item(LangItem::MetaSized, span);
+ let meta_sized_did = tcx.require_lang_item(hir::LangItem::MetaSized, span);
let meta_sized = collect_bounds(hir_bounds, self_ty_where_predicates, meta_sized_did);
- let pointee_sized_did = tcx.require_lang_item(LangItem::PointeeSized, span);
+ let pointee_sized_did = tcx.require_lang_item(hir::LangItem::PointeeSized, span);
let pointee_sized = collect_bounds(hir_bounds, self_ty_where_predicates, pointee_sized_did);
CollectedSizednessBounds { sized, meta_sized, pointee_sized }
@@ -151,24 +151,6 @@ fn add_trait_bound<'tcx>(
}
impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
- /// Skip `PointeeSized` bounds.
- ///
- /// `PointeeSized` is a "fake bound" insofar as anywhere a `PointeeSized` bound exists, there
- /// is actually the absence of any bounds. This avoids limitations around non-global where
- /// clauses being preferred over item bounds (where `PointeeSized` bounds would be
- /// proven) - which can result in errors when a `PointeeSized` supertrait/bound/predicate is
- /// added to some items.
- pub(crate) fn should_skip_sizedness_bound<'hir>(
- &self,
- bound: &'hir hir::GenericBound<'tcx>,
- ) -> bool {
- bound
- .trait_ref()
- .and_then(|tr| tr.trait_def_id())
- .map(|did| self.tcx().is_lang_item(did, LangItem::PointeeSized))
- .unwrap_or(false)
- }
-
/// Adds sizedness bounds to a trait, trait alias, parameter, opaque type or associated type.
///
/// - On parameters, opaque type and associated types, add default `Sized` bound if no explicit
@@ -193,8 +175,8 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
return;
}
- let meta_sized_did = tcx.require_lang_item(LangItem::MetaSized, span);
- let pointee_sized_did = tcx.require_lang_item(LangItem::PointeeSized, span);
+ let meta_sized_did = tcx.require_lang_item(hir::LangItem::MetaSized, span);
+ let pointee_sized_did = tcx.require_lang_item(hir::LangItem::PointeeSized, span);
// If adding sizedness bounds to a trait, then there are some relevant early exits
if let Some(trait_did) = trait_did {
@@ -209,9 +191,22 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
return;
}
} else {
- // Report invalid unbounds on sizedness-bounded generic parameters.
- let unbounds = collect_unbounds(hir_bounds, self_ty_where_predicates);
- self.check_and_report_invalid_unbounds_on_param(unbounds);
+ // Report invalid relaxed bounds.
+ // FIXME: Since we only call this validation function here in this function, we only
+ // fully validate relaxed bounds in contexts where we perform
+ // "sized elaboration". In most cases that doesn't matter because we *usually*
+ // reject relaxed bounds outright during AST lowering.
+ // However, this can easily get out of sync! Ideally, we would perform this step
+ // where we are guaranteed to catch *all* bounds like in
+ // `Self::lower_poly_trait_ref`. List of concrete issues:
+ // FIXME(more_maybe_bounds): We don't call this for e.g., trait object tys or
+ // supertrait bounds!
+ // FIXME(trait_alias, #143122): We don't call it for the RHS. Arguably however,
+ // AST lowering should reject them outright.
+ // FIXME(associated_type_bounds): We don't call this for them. However, AST
+ // lowering should reject them outright (#135229).
+ let bounds = collect_relaxed_bounds(hir_bounds, self_ty_where_predicates);
+ self.check_and_report_invalid_relaxed_bounds(bounds);
}
let collected = collect_sizedness_bounds(tcx, hir_bounds, self_ty_where_predicates, span);
@@ -231,7 +226,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
} else {
// If there are no explicit sizedness bounds on a parameter then add a default
// `Sized` bound.
- let sized_did = tcx.require_lang_item(LangItem::Sized, span);
+ let sized_did = tcx.require_lang_item(hir::LangItem::Sized, span);
add_trait_bound(tcx, bounds, self_ty, sized_did, span);
}
}
@@ -463,10 +458,6 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
'tcx: 'hir,
{
for hir_bound in hir_bounds {
- if self.should_skip_sizedness_bound(hir_bound) {
- continue;
- }
-
// In order to avoid cycles, when we're lowering `SelfTraitThatDefines`,
// we skip over any traits that don't define the given associated type.
if let PredicateFilter::SelfTraitThatDefines(assoc_ident) = predicate_filter {
@@ -482,12 +473,8 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
match hir_bound {
hir::GenericBound::Trait(poly_trait_ref) => {
- let hir::TraitBoundModifiers { constness, polarity } = poly_trait_ref.modifiers;
let _ = self.lower_poly_trait_ref(
- &poly_trait_ref.trait_ref,
- poly_trait_ref.span,
- constness,
- polarity,
+ poly_trait_ref,
param_ty,
bounds,
predicate_filter,
diff --git a/compiler/rustc_hir_analysis/src/hir_ty_lowering/dyn_compatibility.rs b/compiler/rustc_hir_analysis/src/hir_ty_lowering/dyn_compatibility.rs
index cb106962be18e..76bb59e3f0901 100644
--- a/compiler/rustc_hir_analysis/src/hir_ty_lowering/dyn_compatibility.rs
+++ b/compiler/rustc_hir_analysis/src/hir_ty_lowering/dyn_compatibility.rs
@@ -2,7 +2,6 @@ use rustc_data_structures::fx::{FxHashSet, FxIndexMap, FxIndexSet};
use rustc_errors::codes::*;
use rustc_errors::struct_span_code_err;
use rustc_hir as hir;
-use rustc_hir::LangItem;
use rustc_hir::def::{DefKind, Res};
use rustc_lint_defs::builtin::UNUSED_ASSOCIATED_TYPE_BOUNDS;
use rustc_middle::ty::elaborate::ClauseWithSupertraitSpan;
@@ -18,9 +17,7 @@ use tracing::{debug, instrument};
use super::HirTyLowerer;
use crate::errors::SelfInTypeAlias;
-use crate::hir_ty_lowering::{
- GenericArgCountMismatch, GenericArgCountResult, PredicateFilter, RegionInferReason,
-};
+use crate::hir_ty_lowering::{GenericArgCountMismatch, PredicateFilter, RegionInferReason};
impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
/// Lower a trait object type from the HIR to our internal notion of a type.
@@ -38,24 +35,15 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
let mut user_written_bounds = Vec::new();
let mut potential_assoc_types = Vec::new();
- for trait_bound in hir_bounds.iter() {
- if let hir::BoundPolarity::Maybe(_) = trait_bound.modifiers.polarity {
- continue;
- }
- if let GenericArgCountResult {
- correct:
- Err(GenericArgCountMismatch { invalid_args: cur_potential_assoc_types, .. }),
- ..
- } = self.lower_poly_trait_ref(
- &trait_bound.trait_ref,
- trait_bound.span,
- hir::BoundConstness::Never,
- hir::BoundPolarity::Positive,
+ for poly_trait_ref in hir_bounds.iter() {
+ let result = self.lower_poly_trait_ref(
+ poly_trait_ref,
dummy_self,
&mut user_written_bounds,
PredicateFilter::SelfOnly,
- ) {
- potential_assoc_types.extend(cur_potential_assoc_types);
+ );
+ if let Err(GenericArgCountMismatch { invalid_args, .. }) = result.correct {
+ potential_assoc_types.extend(invalid_args);
}
}
@@ -81,13 +69,6 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
let guar = self.report_trait_object_addition_traits(®ular_traits);
return Ty::new_error(tcx, guar);
}
- // We don't support `PointeeSized` principals
- let pointee_sized_did = tcx.require_lang_item(LangItem::PointeeSized, span);
- if regular_traits.iter().any(|(pred, _)| pred.def_id() == pointee_sized_did) {
- let guar = self.report_pointee_sized_trait_object(span);
- return Ty::new_error(tcx, guar);
- }
-
// Don't create a dyn trait if we have errors in the principal.
if let Err(guar) = regular_traits.error_reported() {
return Ty::new_error(tcx, guar);
diff --git a/compiler/rustc_hir_analysis/src/hir_ty_lowering/errors.rs b/compiler/rustc_hir_analysis/src/hir_ty_lowering/errors.rs
index 5d85a3f8455e0..287a5532f0168 100644
--- a/compiler/rustc_hir_analysis/src/hir_ty_lowering/errors.rs
+++ b/compiler/rustc_hir_analysis/src/hir_ty_lowering/errors.rs
@@ -8,7 +8,7 @@ use rustc_errors::{
};
use rustc_hir::def::{CtorOf, DefKind, Res};
use rustc_hir::def_id::DefId;
-use rustc_hir::{self as hir, HirId, LangItem, PolyTraitRef};
+use rustc_hir::{self as hir, HirId, PolyTraitRef};
use rustc_middle::bug;
use rustc_middle::ty::fast_reject::{TreatParams, simplify_type};
use rustc_middle::ty::print::{PrintPolyTraitRefExt as _, PrintTraitRefExt as _};
@@ -29,59 +29,54 @@ use tracing::debug;
use super::InherentAssocCandidate;
use crate::errors::{
self, AssocItemConstraintsNotAllowedHere, ManualImplementation, MissingTypeParams,
- ParenthesizedFnTraitExpansion, PointeeSizedTraitObject, TraitObjectDeclaredWithNoTraits,
+ ParenthesizedFnTraitExpansion, TraitObjectDeclaredWithNoTraits,
};
use crate::fluent_generated as fluent;
use crate::hir_ty_lowering::{AssocItemQSelf, HirTyLowerer};
impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
- /// Check for multiple relaxed default bounds and relaxed bounds of non-sizedness traits.
- pub(crate) fn check_and_report_invalid_unbounds_on_param(
+ /// Check for duplicate relaxed bounds and relaxed bounds of non-default traits.
+ pub(crate) fn check_and_report_invalid_relaxed_bounds(
&self,
- unbounds: SmallVec<[&PolyTraitRef<'_>; 1]>,
+ relaxed_bounds: SmallVec<[&PolyTraitRef<'_>; 1]>,
) {
let tcx = self.tcx();
- let sized_did = tcx.require_lang_item(LangItem::Sized, DUMMY_SP);
+ let mut grouped_bounds = FxIndexMap::<_, Vec<_>>::default();
- let mut unique_bounds = FxIndexSet::default();
- let mut seen_repeat = false;
- for unbound in &unbounds {
- if let Res::Def(DefKind::Trait, unbound_def_id) = unbound.trait_ref.path.res {
- seen_repeat |= !unique_bounds.insert(unbound_def_id);
+ for bound in &relaxed_bounds {
+ if let Res::Def(DefKind::Trait, trait_def_id) = bound.trait_ref.path.res {
+ grouped_bounds.entry(trait_def_id).or_default().push(bound.span);
}
}
- if unbounds.len() > 1 {
- let err = errors::MultipleRelaxedDefaultBounds {
- spans: unbounds.iter().map(|ptr| ptr.span).collect(),
- };
-
- if seen_repeat {
- tcx.dcx().emit_err(err);
- } else if !tcx.features().more_maybe_bounds() {
- tcx.sess.create_feature_err(err, sym::more_maybe_bounds).emit();
- };
+ for (trait_def_id, spans) in grouped_bounds {
+ if spans.len() > 1 {
+ let name = tcx.item_name(trait_def_id);
+ self.dcx()
+ .struct_span_err(spans, format!("duplicate relaxed `{name}` bounds"))
+ .with_code(E0203)
+ .emit();
+ }
}
- for unbound in unbounds {
- if let Res::Def(DefKind::Trait, did) = unbound.trait_ref.path.res
- && ((did == sized_did) || tcx.is_default_trait(did))
+ let sized_def_id = tcx.require_lang_item(hir::LangItem::Sized, DUMMY_SP);
+
+ for bound in relaxed_bounds {
+ if let Res::Def(DefKind::Trait, def_id) = bound.trait_ref.path.res
+ && (def_id == sized_def_id || tcx.is_default_trait(def_id))
{
continue;
}
-
- let unbound_traits = match tcx.sess.opts.unstable_opts.experimental_default_bounds {
- true => "`?Sized` and `experimental_default_bounds`",
- false => "`?Sized`",
- };
self.dcx().span_err(
- unbound.span,
- format!(
- "relaxing a default bound only does something for {}; all other traits are \
- not bound by default",
- unbound_traits
- ),
+ bound.span,
+ if tcx.sess.opts.unstable_opts.experimental_default_bounds
+ || tcx.features().more_maybe_bounds()
+ {
+ "bound modifier `?` can only be applied to default traits like `Sized`"
+ } else {
+ "bound modifier `?` can only be applied to `Sized`"
+ },
);
}
}
@@ -1410,10 +1405,6 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
self.dcx().emit_err(TraitObjectDeclaredWithNoTraits { span, trait_alias_span })
}
-
- pub(super) fn report_pointee_sized_trait_object(&self, span: Span) -> ErrorGuaranteed {
- self.dcx().emit_err(PointeeSizedTraitObject { span })
- }
}
/// Emit an error for the given associated item constraint.
diff --git a/compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs b/compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs
index 55bf2ab6b50e1..51f4007b09ba6 100644
--- a/compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs
+++ b/compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs
@@ -750,18 +750,44 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
/// If for example you had `for<'a> Foo<'a>: Bar<'a>`, then the `self_ty` would be `Foo<'a>`
/// where `'a` is a bound region at depth 0. Similarly, the `trait_ref` would be `Bar<'a>`.
/// The lowered poly-trait-ref will track this binder explicitly, however.
- #[instrument(level = "debug", skip(self, span, constness, bounds))]
+ #[instrument(level = "debug", skip(self, bounds))]
pub(crate) fn lower_poly_trait_ref(
&self,
- trait_ref: &hir::TraitRef<'tcx>,
- span: Span,
- constness: hir::BoundConstness,
- polarity: hir::BoundPolarity,
+ poly_trait_ref: &hir::PolyTraitRef<'tcx>,
self_ty: Ty<'tcx>,
bounds: &mut Vec<(ty::Clause<'tcx>, Span)>,
predicate_filter: PredicateFilter,
) -> GenericArgCountResult {
+ let tcx = self.tcx();
+
+ // We use the *resolved* bound vars later instead of the HIR ones since the former
+ // also include the bound vars of the overarching predicate if applicable.
+ let hir::PolyTraitRef { bound_generic_params: _, modifiers, ref trait_ref, span } =
+ *poly_trait_ref;
+ let hir::TraitBoundModifiers { constness, polarity } = modifiers;
+
let trait_def_id = trait_ref.trait_def_id().unwrap_or_else(|| FatalError.raise());
+
+ let (polarity, bounds) = match polarity {
+ rustc_ast::BoundPolarity::Positive
+ if tcx.is_lang_item(trait_def_id, hir::LangItem::PointeeSized) =>
+ {
+ // Skip `PointeeSized` bounds.
+ //
+ // `PointeeSized` is a "fake bound" insofar as anywhere a `PointeeSized` bound exists, there
+ // is actually the absence of any bounds. This avoids limitations around non-global where
+ // clauses being preferred over item bounds (where `PointeeSized` bounds would be
+ // proven) - which can result in errors when a `PointeeSized` supertrait/bound/predicate is
+ // added to some items.
+ (ty::PredicatePolarity::Positive, &mut Vec::new())
+ }
+ rustc_ast::BoundPolarity::Positive => (ty::PredicatePolarity::Positive, bounds),
+ rustc_ast::BoundPolarity::Negative(_) => (ty::PredicatePolarity::Negative, bounds),
+ rustc_ast::BoundPolarity::Maybe(_) => {
+ (ty::PredicatePolarity::Positive, &mut Vec::new())
+ }
+ };
+
let trait_segment = trait_ref.path.segments.last().unwrap();
let _ = self.prohibit_generic_args(
@@ -778,7 +804,6 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
Some(self_ty),
);
- let tcx = self.tcx();
let bound_vars = tcx.late_bound_vars(trait_ref.hir_ref_id);
debug!(?bound_vars);
@@ -789,27 +814,6 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
debug!(?poly_trait_ref);
- 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;
- }
- };
-
// We deal with const conditions later.
match predicate_filter {
PredicateFilter::All
@@ -912,7 +916,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
// Don't register any associated item constraints for negative bounds,
// since we should have emitted an error for them earlier, and they
// would not be well-formed!
- if polarity != ty::PredicatePolarity::Positive {
+ if polarity == ty::PredicatePolarity::Negative {
self.dcx().span_delayed_bug(
constraint.span,
"negative trait bounds should not have assoc item constraints",
diff --git a/tests/ui/associated-item/missing-associated_item_or_field_def_ids.rs b/tests/ui/associated-item/missing-associated_item_or_field_def_ids.rs
index b90bb9ea4ddf6..029ce7d0e7e49 100644
--- a/tests/ui/associated-item/missing-associated_item_or_field_def_ids.rs
+++ b/tests/ui/associated-item/missing-associated_item_or_field_def_ids.rs
@@ -1,8 +1,7 @@
// Regression test for <https://github.com/rust-lang/rust/issues/137554>.
fn main() -> dyn Iterator + ?Iterator::advance_by(usize) {
- //~^ ERROR `?Trait` is not permitted in trait object types
- //~| ERROR expected trait, found associated function `Iterator::advance_by`
- //~| ERROR the value of the associated type `Item` in `Iterator` must be specified
+ //~^ ERROR expected trait, found associated function `Iterator::advance_by`
+ //~| ERROR relaxed bounds are not permitted in trait object types
todo!()
}
diff --git a/tests/ui/associated-item/missing-associated_item_or_field_def_ids.stderr b/tests/ui/associated-item/missing-associated_item_or_field_def_ids.stderr
index 7f0fbc800ed1c..3dc7fd78e41e8 100644
--- a/tests/ui/associated-item/missing-associated_item_or_field_def_ids.stderr
+++ b/tests/ui/associated-item/missing-associated_item_or_field_def_ids.stderr
@@ -1,25 +1,19 @@
-error[E0658]: `?Trait` is not permitted in trait object types
- --> $DIR/missing-associated_item_or_field_def_ids.rs:3:29
- |
-LL | fn main() -> dyn Iterator + ?Iterator::advance_by(usize) {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
- |
- = help: add `#![feature(more_maybe_bounds)]` 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[E0404]: expected trait, found associated function `Iterator::advance_by`
--> $DIR/missing-associated_item_or_field_def_ids.rs:3:30
|
LL | fn main() -> dyn Iterator + ?Iterator::advance_by(usize) {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^ not a trait
-error[E0191]: the value of the associated type `Item` in `Iterator` must be specified
- --> $DIR/missing-associated_item_or_field_def_ids.rs:3:18
+error[E0658]: relaxed bounds are not permitted in trait object types
+ --> $DIR/missing-associated_item_or_field_def_ids.rs:3:29
|
LL | fn main() -> dyn Iterator + ?Iterator::advance_by(usize) {
- | ^^^^^^^^ help: specify the associated type: `Iterator<Item = Type>`
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+ |
+ = help: add `#![feature(more_maybe_bounds)]` 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 3 previous errors
+error: aborting due to 2 previous errors
-Some errors have detailed explanations: E0191, E0404, E0658.
-For more information about an error, try `rustc --explain E0191`.
+Some errors have detailed explanations: E0404, E0658.
+For more information about an error, try `rustc --explain E0404`.
diff --git a/tests/ui/associated-types/avoid-getting-associated-items-of-undefined-trait.rs b/tests/ui/associated-types/avoid-getting-associated-items-of-undefined-trait.rs
index f6b749a5100b9..bac4e60886772 100644
--- a/tests/ui/associated-types/avoid-getting-associated-items-of-undefined-trait.rs
+++ b/tests/ui/associated-types/avoid-getting-associated-items-of-undefined-trait.rs
@@ -6,7 +6,6 @@ trait Tr {
fn main() {
let _: dyn Tr + ?Foo<Assoc = ()>;
- //~^ ERROR: `?Trait` is not permitted in trait object types
- //~| ERROR: cannot find trait `Foo` in this scope
- //~| ERROR: the value of the associated type `Item` in `Tr` must be specified
+ //~^ ERROR: cannot find trait `Foo` in this scope
+ //~| ERROR: relaxed bounds are not permitted in trait object types
}
diff --git a/tests/ui/associated-types/avoid-getting-associated-items-of-undefined-trait.stderr b/tests/ui/associated-types/avoid-getting-associated-items-of-undefined-trait.stderr
index f31a1de76a790..3b35c164d37d4 100644
--- a/tests/ui/associated-types/avoid-getting-associated-items-of-undefined-trait.stderr
+++ b/tests/ui/associated-types/avoid-getting-associated-items-of-undefined-trait.stderr
@@ -1,28 +1,19 @@
-error[E0658]: `?Trait` is not permitted in trait object types
- --> $DIR/avoid-getting-associated-items-of-undefined-trait.rs:8:21
- |
-LL | let _: dyn Tr + ?Foo<Assoc = ()>;
- | ^^^^^^^^^^^^^^^^
- |
- = help: add `#![feature(more_maybe_bounds)]` 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[E0405]: cannot find trait `Foo` in this scope
--> $DIR/avoid-getting-associated-items-of-undefined-trait.rs:8:22
|
LL | let _: dyn Tr + ?Foo<Assoc = ()>;
| ^^^ not found in this scope
-error[E0191]: the value of the associated type `Item` in `Tr` must be specified
- --> $DIR/avoid-getting-associated-items-of-undefined-trait.rs:8:16
+error[E0658]: relaxed bounds are not permitted in trait object types
+ --> $DIR/avoid-getting-associated-items-of-undefined-trait.rs:8:21
|
-LL | type Item;
- | --------- `Item` defined here
-...
LL | let _: dyn Tr + ?Foo<Assoc = ()>;
- | ^^ help: specify the associated type: `Tr<Item = Type>`
+ | ^^^^^^^^^^^^^^^^
+ |
+ = help: add `#![feature(more_maybe_bounds)]` 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 3 previous errors
+error: aborting due to 2 previous errors
-Some errors have detailed explanations: E0191, E0405, E0658.
-For more information about an error, try `rustc --explain E0191`.
+Some errors have detailed explanations: E0405, E0658.
+For more information about an error, try `rustc --explain E0405`.
diff --git a/tests/ui/feature-gates/feature-gate-more-maybe-bounds.rs b/tests/ui/feature-gates/feature-gate-more-maybe-bounds.rs
index 6a832744e3ee9..9c727ae3aad4c 100644
--- a/tests/ui/feature-gates/feature-gate-more-maybe-bounds.rs
+++ b/tests/ui/feature-gates/feature-gate-more-maybe-bounds.rs
@@ -2,23 +2,13 @@
trait Trait1 {}
auto trait Trait2 {}
-trait Trait3: ?Trait1 {}
-//~^ ERROR `?Trait` is not permitted in supertraits
-trait Trait4 where Self: ?Trait1 {}
-//~^ ERROR ?Trait` bounds are only permitted at the point where a type parameter is declared
+trait Trait3: ?Trait1 {} //~ ERROR relaxed bounds are not permitted in supertrait bounds
+trait Trait4 where Self: ?Trait1 {} //~ ERROR this relaxed bound is not permitted here
fn foo(_: Box<dyn Trait1 + ?Trait2>) {}
-//~^ ERROR `?Trait` is not permitted in trait object types
+//~^ ERROR relaxed bounds are not permitted in trait object types
fn bar<T: ?Trait1 + ?Trait2>(_: T) {}
-//~^ ERROR type parameter has more than one relaxed default bound, only one is supported
-//~| ERROR relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
-//~| ERROR relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
-
-trait Trait {}
-// Do not suggest `#![feature(more_maybe_bounds)]` for repetitions
-fn baz<T: ?Trait + ?Trait>(_ : T) {}
-//~^ ERROR type parameter has more than one relaxed default bound, only one is supported
-//~| ERROR relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
-//~| ERROR relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
+//~^ ERROR bound modifier `?` can only be applied to `Sized`
+//~| ERROR bound modifier `?` can only be applied to `Sized`
fn main() {}
diff --git a/tests/ui/feature-gates/feature-gate-more-maybe-bounds.stderr b/tests/ui/feature-gates/feature-gate-more-maybe-bounds.stderr
index 729df4eb37cac..d01d9cbef3adc 100644
--- a/tests/ui/feature-gates/feature-gate-more-maybe-bounds.stderr
+++ b/tests/ui/feature-gates/feature-gate-more-maybe-bounds.stderr
@@ -1,71 +1,43 @@
-error[E0658]: `?Trait` is not permitted in supertraits
+error[E0658]: relaxed bounds are not permitted in supertrait bounds
--> $DIR/feature-gate-more-maybe-bounds.rs:5:15
|
LL | trait Trait3: ?Trait1 {}
| ^^^^^^^
|
- = note: traits are `?Trait1` by default
= help: add `#![feature(more_maybe_bounds)]` 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[E0658]: `?Trait` is not permitted in trait object types
- --> $DIR/feature-gate-more-maybe-bounds.rs:10:28
- |
-LL | fn foo(_: Box<dyn Trait1 + ?Trait2>) {}
- | ^^^^^^^
- |
- = help: add `#![feature(more_maybe_bounds)]` 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[E0658]: `?Trait` bounds are only permitted at the point where a type parameter is declared
- --> $DIR/feature-gate-more-maybe-bounds.rs:7:26
+error[E0658]: this relaxed bound is not permitted here
+ --> $DIR/feature-gate-more-maybe-bounds.rs:6:26
|
LL | trait Trait4 where Self: ?Trait1 {}
| ^^^^^^^
|
= help: add `#![feature(more_maybe_bounds)]` to the crate attributes to enable
= note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
+ = note: in this context, relaxed bounds are only allowed on type parameters defined by the closest item
-error[E0203]: type parameter has more than one relaxed default bound, only one is supported
- --> $DIR/feature-gate-more-maybe-bounds.rs:12:11
+error[E0658]: relaxed bounds are not permitted in trait object types
+ --> $DIR/feature-gate-more-maybe-bounds.rs:8:28
|
-LL | fn bar<T: ?Trait1 + ?Trait2>(_: T) {}
- | ^^^^^^^ ^^^^^^^
+LL | fn foo(_: Box<dyn Trait1 + ?Trait2>) {}
+ | ^^^^^^^
|
= help: add `#![feature(more_maybe_bounds)]` 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: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
- --> $DIR/feature-gate-more-maybe-bounds.rs:12:11
+error: bound modifier `?` can only be applied to `Sized`
+ --> $DIR/feature-gate-more-maybe-bounds.rs:10:11
|
LL | fn bar<T: ?Trait1 + ?Trait2>(_: T) {}
| ^^^^^^^
-error: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
- --> $DIR/feature-gate-more-maybe-bounds.rs:12:21
+error: bound modifier `?` can only be applied to `Sized`
+ --> $DIR/feature-gate-more-maybe-bounds.rs:10:21
|
LL | fn bar<T: ?Trait1 + ?Trait2>(_: T) {}
| ^^^^^^^
-error[E0203]: type parameter has more than one relaxed default bound, only one is supported
- --> $DIR/feature-gate-more-maybe-bounds.rs:19:11
- |
-LL | fn baz<T: ?Trait + ?Trait>(_ : T) {}
- | ^^^^^^ ^^^^^^
-
-error: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
- --> $DIR/feature-gate-more-maybe-bounds.rs:19:11
- |
-LL | fn baz<T: ?Trait + ?Trait>(_ : T) {}
- | ^^^^^^
-
-error: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
- --> $DIR/feature-gate-more-maybe-bounds.rs:19:20
- |
-LL | fn baz<T: ?Trait + ?Trait>(_ : T) {}
- | ^^^^^^
-
-error: aborting due to 9 previous errors
+error: aborting due to 5 previous errors
-Some errors have detailed explanations: E0203, E0658.
-For more information about an error, try `rustc --explain E0203`.
+For more information about this error, try `rustc --explain E0658`.
diff --git a/tests/ui/impl-trait/opt-out-bound-not-satisfied.rs b/tests/ui/impl-trait/opt-out-bound-not-satisfied.rs
index 27c493a13bf91..7e0e1eadf9c75 100644
--- a/tests/ui/impl-trait/opt-out-bound-not-satisfied.rs
+++ b/tests/ui/impl-trait/opt-out-bound-not-satisfied.rs
@@ -3,8 +3,8 @@
use std::future::Future;
fn foo() -> impl ?Future<Output = impl Send> {
- //~^ ERROR: relaxing a default bound only does something for `?Sized`
- //~| ERROR: relaxing a default bound only does something for `?Sized`
+ //~^ ERROR: bound modifier `?` can only be applied to `Sized`
+ //~| ERROR: bound modifier `?` can only be applied to `Sized`
()
}
diff --git a/tests/ui/impl-trait/opt-out-bound-not-satisfied.stderr b/tests/ui/impl-trait/opt-out-bound-not-satisfied.stderr
index dc4314c58ad2f..f99d6a7e5f6d0 100644
--- a/tests/ui/impl-trait/opt-out-bound-not-satisfied.stderr
+++ b/tests/ui/impl-trait/opt-out-bound-not-satisfied.stderr
@@ -1,10 +1,10 @@
-error: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
+error: bound modifier `?` can only be applied to `Sized`
--> $DIR/opt-out-bound-not-satisfied.rs:5:18
|
LL | fn foo() -> impl ?Future<Output = impl Send> {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^
-error: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
+error: bound modifier `?` can only be applied to `Sized`
--> $DIR/opt-out-bound-not-satisfied.rs:5:18
|
LL | fn foo() -> impl ?Future<Output = impl Send> {
diff --git a/tests/ui/issues/issue-37534.rs b/tests/ui/issues/issue-37534.rs
index 09d60b7786b99..63f6479ae2e24 100644
--- a/tests/ui/issues/issue-37534.rs
+++ b/tests/ui/issues/issue-37534.rs
@@ -1,5 +1,5 @@
struct Foo<T: ?Hash> {}
//~^ ERROR expected trait, found derive macro `Hash`
-//~| ERROR relaxing a default bound only does something for `?Sized`
+//~| ERROR bound modifier `?` can only be applied to `Sized`
fn main() {}
diff --git a/tests/ui/issues/issue-37534.stderr b/tests/ui/issues/issue-37534.stderr
index 3219854bc70ce..0860735420301 100644
--- a/tests/ui/issues/issue-37534.stderr
+++ b/tests/ui/issues/issue-37534.stderr
@@ -9,7 +9,7 @@ help: consider importing this trait instead
LL + use std::hash::Hash;
|
-error: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
+error: bound modifier `?` can only be applied to `Sized`
--> $DIR/issue-37534.rs:1:15
|
LL | struct Foo<T: ?Hash> {}
diff --git a/tests/ui/issues/issue-87199.rs b/tests/ui/issues/issue-87199.rs
index 4e4e35c6a71e8..dd9dfc74ca352 100644
--- a/tests/ui/issues/issue-87199.rs
+++ b/tests/ui/issues/issue-87199.rs
@@ -6,12 +6,12 @@
// Check that these function definitions only emit warnings, not errors
fn arg<T: ?Send>(_: T) {}
-//~^ ERROR: relaxing a default bound only does something for `?Sized`
+//~^ ERROR: bound modifier `?` can only be applied to `Sized`
fn ref_arg<T: ?Send>(_: &T) {}
-//~^ ERROR: relaxing a default bound only does something for `?Sized`
+//~^ ERROR: bound modifier `?` can only be applied to `Sized`
fn ret() -> impl Iterator<Item = ()> + ?Send { std::iter::empty() }
-//~^ ERROR: relaxing a default bound only does something for `?Sized`
-//~| ERROR: relaxing a default bound only does something for `?Sized`
+//~^ ERROR: bound modifier `?` can only be applied to `Sized`
+//~| ERROR: bound modifier `?` can only be applied to `Sized`
// Check that there's no `?Sized` relaxation!
fn main() {
diff --git a/tests/ui/issues/issue-87199.stderr b/tests/ui/issues/issue-87199.stderr
index acc4e84779c9c..8a930a3d704c1 100644
--- a/tests/ui/issues/issue-87199.stderr
+++ b/tests/ui/issues/issue-87199.stderr
@@ -1,22 +1,22 @@
-error: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
+error: bound modifier `?` can only be applied to `Sized`
--> $DIR/issue-87199.rs:8:11
|
LL | fn arg<T: ?Send>(_: T) {}
| ^^^^^
-error: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
+error: bound modifier `?` can only be applied to `Sized`
--> $DIR/issue-87199.rs:10:15
|
LL | fn ref_arg<T: ?Send>(_: &T) {}
| ^^^^^
-error: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
+error: bound modifier `?` can only be applied to `Sized`
--> $DIR/issue-87199.rs:12:40
|
LL | fn ret() -> impl Iterator<Item = ()> + ?Send { std::iter::empty() }
| ^^^^^
-error: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
+error: bound modifier `?` can only be applied to `Sized`
--> $DIR/issue-87199.rs:12:40
|
LL | fn ret() -> impl Iterator<Item = ()> + ?Send { std::iter::empty() }
diff --git a/tests/ui/parser/trait-object-trait-parens.rs b/tests/ui/parser/trait-object-trait-parens.rs
index 438034bc38aa4..51f0e2de6116f 100644
--- a/tests/ui/parser/trait-object-trait-parens.rs
+++ b/tests/ui/parser/trait-object-trait-parens.rs
@@ -6,17 +6,17 @@ fn f<T: (Copy) + (?Sized) + (for<'a> Trait<'a>)>() {}
fn main() {
let _: Box<(Obj) + (?Sized) + (for<'a> Trait<'a>)>;
- //~^ ERROR `?Trait` is not permitted in trait object types
+ //~^ ERROR relaxed bounds are not permitted in trait object types
//~| ERROR only auto traits can be used as additional traits
//~| WARN trait objects without an explicit `dyn` are deprecated
//~| WARN this is accepted in the current edition
let _: Box<?Sized + (for<'a> Trait<'a>) + (Obj)>;
- //~^ ERROR `?Trait` is not permitted in trait object types
+ //~^ ERROR relaxed bounds are not permitted in trait object types
//~| ERROR only auto traits can be used as additional traits
//~| WARN trait objects without an explicit `dyn` are deprecated
//~| WARN this is accepted in the current edition
let _: Box<for<'a> Trait<'a> + (Obj) + (?Sized)>;
- //~^ ERROR `?Trait` is not permitted in trait object types
+ //~^ ERROR relaxed bounds are not permitted in trait object types
//~| ERROR only auto traits can be used as additional traits
//~| WARN trait objects without an explicit `dyn` are deprecated
//~| WARN this is accepted in the current edition
diff --git a/tests/ui/parser/trait-object-trait-parens.stderr b/tests/ui/parser/trait-object-trait-parens.stderr
index d75352b6811ea..8f8ddeac1c5aa 100644
--- a/tests/ui/parser/trait-object-trait-parens.stderr
+++ b/tests/ui/parser/trait-object-trait-parens.stderr
@@ -1,4 +1,4 @@
-error[E0658]: `?Trait` is not permitted in trait object types
+error[E0658]: relaxed bounds are not permitted in trait object types
--> $DIR/trait-object-trait-parens.rs:8:24
|
LL | let _: Box<(Obj) + (?Sized) + (for<'a> Trait<'a>)>;
@@ -7,7 +7,7 @@ LL | let _: Box<(Obj) + (?Sized) + (for<'a> Trait<'a>)>;
= help: add `#![feature(more_maybe_bounds)]` 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[E0658]: `?Trait` is not permitted in trait object types
+error[E0658]: relaxed bounds are not permitted in trait object types
--> $DIR/trait-object-trait-parens.rs:13:16
|
LL | let _: Box<?Sized + (for<'a> Trait<'a>) + (Obj)>;
@@ -16,7 +16,7 @@ LL | let _: Box<?Sized + (for<'a> Trait<'a>) + (Obj)>;
= help: add `#![feature(more_maybe_bounds)]` 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[E0658]: `?Trait` is not permitted in trait object types
+error[E0658]: relaxed bounds are not permitted in trait object types
--> $DIR/trait-object-trait-parens.rs:18:44
|
LL | let _: Box<for<'a> Trait<'a> + (Obj) + (?Sized)>;
diff --git a/tests/ui/sized-hierarchy/default-bound.rs b/tests/ui/sized-hierarchy/default-bound.rs
index 12b2eb2b5c1b4..bbb2c6d96baa8 100644
--- a/tests/ui/sized-hierarchy/default-bound.rs
+++ b/tests/ui/sized-hierarchy/default-bound.rs
@@ -14,13 +14,13 @@ fn neg_sized<T: ?Sized>() {}
fn metasized<T: MetaSized>() {}
fn neg_metasized<T: ?MetaSized>() {}
-//~^ ERROR relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
+//~^ ERROR bound modifier `?` can only be applied to `Sized`
fn pointeesized<T: PointeeSized>() { }
fn neg_pointeesized<T: ?PointeeSized>() { }
-//~^ ERROR relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
+//~^ ERROR bound modifier `?` can only be applied to `Sized`
fn main() {
diff --git a/tests/ui/sized-hierarchy/default-bound.stderr b/tests/ui/sized-hierarchy/default-bound.stderr
index 22f0fa29d3e23..0a4ea6f44d8ed 100644
--- a/tests/ui/sized-hierarchy/default-bound.stderr
+++ b/tests/ui/sized-hierarchy/default-bound.stderr
@@ -1,10 +1,10 @@
-error: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
+error: bound modifier `?` can only be applied to `Sized`
--> $DIR/default-bound.rs:16:21
|
LL | fn neg_metasized<T: ?MetaSized>() {}
| ^^^^^^^^^^
-error: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
+error: bound modifier `?` can only be applied to `Sized`
--> $DIR/default-bound.rs:22:24
|
LL | fn neg_pointeesized<T: ?PointeeSized>() { }
diff --git a/tests/ui/sized-hierarchy/default-supertrait.rs b/tests/ui/sized-hierarchy/default-supertrait.rs
index b25acf9e6ea4f..ab3b28e84db5a 100644
--- a/tests/ui/sized-hierarchy/default-supertrait.rs
+++ b/tests/ui/sized-hierarchy/default-supertrait.rs
@@ -6,18 +6,18 @@ use std::marker::{MetaSized, PointeeSized};
trait Sized_: Sized { }
trait NegSized: ?Sized { }
-//~^ ERROR `?Trait` is not permitted in supertraits
+//~^ ERROR relaxed bounds are not permitted in supertrait bounds
trait MetaSized_: MetaSized { }
trait NegMetaSized: ?MetaSized { }
-//~^ ERROR `?Trait` is not permitted in supertraits
+//~^ ERROR relaxed bounds are not permitted in supertrait bounds
trait PointeeSized_: PointeeSized { }
trait NegPointeeSized: ?PointeeSized { }
-//~^ ERROR `?Trait` is not permitted in supertraits
+//~^ ERROR relaxed bounds are not permitted in supertrait bounds
trait Bare {}
diff --git a/tests/ui/sized-hierarchy/default-supertrait.stderr b/tests/ui/sized-hierarchy/default-supertrait.stderr
index de23936b900bc..77cb9755d4a1c 100644
--- a/tests/ui/sized-hierarchy/default-supertrait.stderr
+++ b/tests/ui/sized-hierarchy/default-supertrait.stderr
@@ -1,30 +1,28 @@
-error[E0658]: `?Trait` is not permitted in supertraits
+error[E0658]: relaxed bounds are not permitted in supertrait bounds
--> $DIR/default-supertrait.rs:8:17
|
LL | trait NegSized: ?Sized { }
| ^^^^^^
|
- = note: traits are `?Sized` by default
= help: add `#![feature(more_maybe_bounds)]` to the crate attributes to enable
= note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
+ = note: traits are `?Sized` by default
-error[E0658]: `?Trait` is not permitted in supertraits
+error[E0658]: relaxed bounds are not permitted in supertrait bounds
--> $DIR/default-supertrait.rs:13:21
|
LL | trait NegMetaSized: ?MetaSized { }
| ^^^^^^^^^^
|
- = note: traits are `?MetaSized` by default
= help: add `#![feature(more_maybe_bounds)]` 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[E0658]: `?Trait` is not permitted in supertraits
+error[E0658]: relaxed bounds are not permitted in supertrait bounds
--> $DIR/default-supertrait.rs:19:24
|
LL | trait NegPointeeSized: ?PointeeSized { }
| ^^^^^^^^^^^^^
|
- = note: traits are `?PointeeSized` by default
= help: add `#![feature(more_maybe_bounds)]` to the crate attributes to enable
= note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
diff --git a/tests/ui/sized-hierarchy/pointee-validation.rs b/tests/ui/sized-hierarchy/pointee-validation.rs
new file mode 100644
index 0000000000000..c80b26b310ae5
--- /dev/null
+++ b/tests/ui/sized-hierarchy/pointee-validation.rs
@@ -0,0 +1,20 @@
+// Test that despite us dropping `PointeeSized` bounds during HIR ty lowering
+// we still validate it first.
+// issue: <https://github.com/rust-lang/rust/issues/142718>
+#![feature(sized_hierarchy)]
+
+use std::marker::PointeeSized;
+
+struct T where (): PointeeSized<(), Undefined = ()>;
+//~^ ERROR trait takes 0 generic arguments but 1 generic argument was supplied
+//~| ERROR associated type `Undefined` not found for `PointeeSized`
+
+const fn test<T, U>() where T: const PointeeSized, U: [const] PointeeSized {}
+//~^ ERROR `const` can only be applied to `#[const_trait]` traits
+//~| ERROR `const` can only be applied to `#[const_trait]` traits
+//~| ERROR const trait impls are experimental
+//~| ERROR `[const]` can only be applied to `#[const_trait]` traits
+//~| ERROR `[const]` can only be applied to `#[const_trait]` traits
+//~| ERROR const trait impls are experimental
+
+fn main() {}
diff --git a/tests/ui/sized-hierarchy/pointee-validation.stderr b/tests/ui/sized-hierarchy/pointee-validation.stderr
new file mode 100644
index 0000000000000..36500290e6c4d
--- /dev/null
+++ b/tests/ui/sized-hierarchy/pointee-validation.stderr
@@ -0,0 +1,76 @@
+error[E0658]: const trait impls are experimental
+ --> $DIR/pointee-validation.rs:12:32
+ |
+LL | const fn test<T, U>() where T: const PointeeSized, U: [const] PointeeSized {}
+ | ^^^^^
+ |
+ = note: see issue #67792 <https://github.com/rust-lang/rust/issues/67792> for more information
+ = 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
+
+error[E0658]: const trait impls are experimental
+ --> $DIR/pointee-validation.rs:12:55
+ |
+LL | const fn test<T, U>() where T: const PointeeSized, U: [const] PointeeSized {}
+ | ^^^^^^^
+ |
+ = note: see issue #67792 <https://github.com/rust-lang/rust/issues/67792> for more information
+ = 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
+
+error[E0107]: trait takes 0 generic arguments but 1 generic argument was supplied
+ --> $DIR/pointee-validation.rs:8:20
+ |
+LL | struct T where (): PointeeSized<(), Undefined = ()>;
+ | ^^^^^^^^^^^^-------------------- help: remove the unnecessary generics
+ | |
+ | expected 0 generic arguments
+
+error[E0220]: associated type `Undefined` not found for `PointeeSized`
+ --> $DIR/pointee-validation.rs:8:37
+ |
+LL | struct T where (): PointeeSized<(), Undefined = ()>;
+ | ^^^^^^^^^ associated type `Undefined` not found
+
+error: `const` can only be applied to `#[const_trait]` traits
+ --> $DIR/pointee-validation.rs:12:32
+ |
+LL | const fn test<T, U>() where T: const PointeeSized, U: [const] PointeeSized {}
+ | ^^^^^ can't be applied to `PointeeSized`
+ |
+note: `PointeeSized` can't be used with `const` because it isn't annotated with `#[const_trait]`
+ --> $SRC_DIR/core/src/marker.rs:LL:COL
+
+error: `[const]` can only be applied to `#[const_trait]` traits
+ --> $DIR/pointee-validation.rs:12:55
+ |
+LL | const fn test<T, U>() where T: const PointeeSized, U: [const] PointeeSized {}
+ | ^^^^^^^ can't be applied to `PointeeSized`
+ |
+note: `PointeeSized` can't be used with `[const]` because it isn't annotated with `#[const_trait]`
+ --> $SRC_DIR/core/src/marker.rs:LL:COL
+
+error: `const` can only be applied to `#[const_trait]` traits
+ --> $DIR/pointee-validation.rs:12:32
+ |
+LL | const fn test<T, U>() where T: const PointeeSized, U: [const] PointeeSized {}
+ | ^^^^^ can't be applied to `PointeeSized`
+ |
+note: `PointeeSized` can't be used with `const` because it isn't annotated with `#[const_trait]`
+ --> $SRC_DIR/core/src/marker.rs:LL:COL
+ = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+error: `[const]` can only be applied to `#[const_trait]` traits
+ --> $DIR/pointee-validation.rs:12:55
+ |
+LL | const fn test<T, U>() where T: const PointeeSized, U: [const] PointeeSized {}
+ | ^^^^^^^ can't be applied to `PointeeSized`
+ |
+note: `PointeeSized` can't be used with `[const]` because it isn't annotated with `#[const_trait]`
+ --> $SRC_DIR/core/src/marker.rs:LL:COL
+ = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+error: aborting due to 8 previous errors
+
+Some errors have detailed explanations: E0107, E0220, E0658.
+For more information about an error, try `rustc --explain E0107`.
diff --git a/tests/ui/sized-hierarchy/reject-dyn-pointeesized.rs b/tests/ui/sized-hierarchy/reject-dyn-pointeesized.rs
index ece1702679d00..89e4c15371d4a 100644
--- a/tests/ui/sized-hierarchy/reject-dyn-pointeesized.rs
+++ b/tests/ui/sized-hierarchy/reject-dyn-pointeesized.rs
@@ -3,7 +3,7 @@
use std::marker::PointeeSized;
type Foo = dyn PointeeSized;
-//~^ ERROR `PointeeSized` cannot be used with trait objects
+//~^ ERROR at least one trait is required for an object type
fn foo(f: &Foo) {}
@@ -12,5 +12,5 @@ fn main() {
let x = main;
let y: Box<dyn PointeeSized> = x;
-//~^ ERROR `PointeeSized` cannot be used with trait objects
+//~^ ERROR at least one trait is required for an object type
}
diff --git a/tests/ui/sized-hierarchy/reject-dyn-pointeesized.stderr b/tests/ui/sized-hierarchy/reject-dyn-pointeesized.stderr
index a833c6952fdc5..616b2400f8650 100644
--- a/tests/ui/sized-hierarchy/reject-dyn-pointeesized.stderr
+++ b/tests/ui/sized-hierarchy/reject-dyn-pointeesized.stderr
@@ -1,10 +1,10 @@
-error: `PointeeSized` cannot be used with trait objects
+error[E0224]: at least one trait is required for an object type
--> $DIR/reject-dyn-pointeesized.rs:5:12
|
LL | type Foo = dyn PointeeSized;
| ^^^^^^^^^^^^^^^^
-error: `PointeeSized` cannot be used with trait objects
+error[E0224]: at least one trait is required for an object type
--> $DIR/reject-dyn-pointeesized.rs:14:16
|
LL | let y: Box<dyn PointeeSized> = x;
@@ -12,3 +12,4 @@ LL | let y: Box<dyn PointeeSized> = x;
error: aborting due to 2 previous errors
+For more information about this error, try `rustc --explain E0224`.
diff --git a/tests/ui/trait-bounds/duplicate-relaxed-bounds.rs b/tests/ui/trait-bounds/duplicate-relaxed-bounds.rs
new file mode 100644
index 0000000000000..a1681ddec77b0
--- /dev/null
+++ b/tests/ui/trait-bounds/duplicate-relaxed-bounds.rs
@@ -0,0 +1,22 @@
+fn dupes<T: ?Sized + ?Sized + ?Iterator + ?Iterator>() {}
+//~^ ERROR duplicate relaxed `Sized` bounds
+//~| ERROR duplicate relaxed `Iterator` bounds
+//~| ERROR bound modifier `?` can only be applied to `Sized`
+//~| ERROR bound modifier `?` can only be applied to `Sized`
+
+trait Trait {
+ // We used to say "type parameter has more than one relaxed default bound"
+ // even on *associated types* like here. Test that we no longer do that.
+ type Type: ?Sized + ?Sized;
+ //~^ ERROR duplicate relaxed `Sized` bounds
+ //~| ERROR duplicate relaxed `Sized` bounds
+}
+
+// We used to emit an additional error about "multiple relaxed default bounds".
+// However, multiple relaxed bounds are actually *fine* if they're distinct.
+// Ultimately, we still reject this because `Sized` is
+// the only (stable) default trait, so we're fine.
+fn not_dupes<T: ?Sized + ?Iterator>() {}
+//~^ ERROR bound modifier `?` can only be applied to `Sized`
+
+fn main() {}
diff --git a/tests/ui/trait-bounds/duplicate-relaxed-bounds.stderr b/tests/ui/trait-bounds/duplicate-relaxed-bounds.stderr
new file mode 100644
index 0000000000000..ccc723fc7a653
--- /dev/null
+++ b/tests/ui/trait-bounds/duplicate-relaxed-bounds.stderr
@@ -0,0 +1,47 @@
+error[E0203]: duplicate relaxed `Sized` bounds
+ --> $DIR/duplicate-relaxed-bounds.rs:1:13
+ |
+LL | fn dupes<T: ?Sized + ?Sized + ?Iterator + ?Iterator>() {}
+ | ^^^^^^ ^^^^^^
+
+error[E0203]: duplicate relaxed `Iterator` bounds
+ --> $DIR/duplicate-relaxed-bounds.rs:1:31
+ |
+LL | fn dupes<T: ?Sized + ?Sized + ?Iterator + ?Iterator>() {}
+ | ^^^^^^^^^ ^^^^^^^^^
+
+error: bound modifier `?` can only be applied to `Sized`
+ --> $DIR/duplicate-relaxed-bounds.rs:1:31
+ |
+LL | fn dupes<T: ?Sized + ?Sized + ?Iterator + ?Iterator>() {}
+ | ^^^^^^^^^
+
+error: bound modifier `?` can only be applied to `Sized`
+ --> $DIR/duplicate-relaxed-bounds.rs:1:43
+ |
+LL | fn dupes<T: ?Sized + ?Sized + ?Iterator + ?Iterator>() {}
+ | ^^^^^^^^^
+
+error: bound modifier `?` can only be applied to `Sized`
+ --> $DIR/duplicate-relaxed-bounds.rs:19:26
+ |
+LL | fn not_dupes<T: ?Sized + ?Iterator>() {}
+ | ^^^^^^^^^
+
+error[E0203]: duplicate relaxed `Sized` bounds
+ --> $DIR/duplicate-relaxed-bounds.rs:10:16
+ |
+LL | type Type: ?Sized + ?Sized;
+ | ^^^^^^ ^^^^^^
+
+error[E0203]: duplicate relaxed `Sized` bounds
+ --> $DIR/duplicate-relaxed-bounds.rs:10:16
+ |
+LL | type Type: ?Sized + ?Sized;
+ | ^^^^^^ ^^^^^^
+ |
+ = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+error: aborting due to 7 previous errors
+
+For more information about this error, try `rustc --explain E0203`.
diff --git a/tests/ui/trait-bounds/bad-suggestionf-for-repeated-unsized-bound-127441.rs b/tests/ui/trait-bounds/fix-dyn-sized-fn-param-sugg.rs
similarity index 51%
rename from tests/ui/trait-bounds/bad-suggestionf-for-repeated-unsized-bound-127441.rs
rename to tests/ui/trait-bounds/fix-dyn-sized-fn-param-sugg.rs
index e6d7f74880fb2..1aa36207bc3ea 100644
--- a/tests/ui/trait-bounds/bad-suggestionf-for-repeated-unsized-bound-127441.rs
+++ b/tests/ui/trait-bounds/fix-dyn-sized-fn-param-sugg.rs
@@ -1,39 +1,38 @@
-// Regression test for #127441
-
-// Tests that we make the correct suggestion
-// in case there are more than one `?Sized`
-// bounds on a function parameter
+// Test that we emit a correct structured suggestions for dynamically sized ("maybe unsized")
+// function parameters.
+// We used to emit a butchered suggestion if duplicate relaxed `Sized` bounds were present.
+// issue: <https://github.com/rust-lang/rust/issues/127441>.
use std::fmt::Debug;
fn foo1<T: ?Sized>(a: T) {}
-//~^ ERROR he size for values of type `T` cannot be known at compilation time
+//~^ ERROR the size for values of type `T` cannot be known at compilation time
fn foo2<T: ?Sized + ?Sized>(a: T) {}
-//~^ ERROR type parameter has more than one relaxed default bound, only one is supported
+//~^ ERROR duplicate relaxed `Sized` bounds
//~| ERROR the size for values of type `T` cannot be known at compilation time
fn foo3<T: ?Sized + ?Sized + Debug>(a: T) {}
-//~^ ERROR type parameter has more than one relaxed default bound, only one is supported
-//~| ERROR he size for values of type `T` cannot be known at compilation time
+//~^ ERROR duplicate relaxed `Sized` bounds
+//~| ERROR the size for values of type `T` cannot be known at compilation time
fn foo4<T: ?Sized + Debug + ?Sized >(a: T) {}
-//~^ ERROR type parameter has more than one relaxed default bound, only one is supported
+//~^ ERROR duplicate relaxed `Sized` bounds
//~| ERROR the size for values of type `T` cannot be known at compilation time
fn foo5(_: impl ?Sized) {}
//~^ ERROR the size for values of type `impl ?Sized` cannot be known at compilation time
fn foo6(_: impl ?Sized + ?Sized) {}
-//~^ ERROR type parameter has more than one relaxed default bound, only one is supported
+//~^ ERROR duplicate relaxed `Sized` bounds
//~| ERROR the size for values of type `impl ?Sized + ?Sized` cannot be known at compilation tim
fn foo7(_: impl ?Sized + ?Sized + Debug) {}
-//~^ ERROR type parameter has more than one relaxed default bound, only one is supported
+//~^ ERROR duplicate relaxed `Sized` bounds
//~| ERROR the size for values of type `impl ?Sized + ?Sized + Debug` cannot be known at compilation time
fn foo8(_: impl ?Sized + Debug + ?Sized ) {}
-//~^ ERROR type parameter has more than one relaxed default bound, only one is supported
+//~^ ERROR duplicate relaxed `Sized` bounds
//~| ERROR the size for values of type `impl ?Sized + Debug + ?Sized` cannot be known at compilation time
fn main() {}
diff --git a/tests/ui/trait-bounds/bad-suggestionf-for-repeated-unsized-bound-127441.stderr b/tests/ui/trait-bounds/fix-dyn-sized-fn-param-sugg.stderr
similarity index 80%
rename from tests/ui/trait-bounds/bad-suggestionf-for-repeated-unsized-bound-127441.stderr
rename to tests/ui/trait-bounds/fix-dyn-sized-fn-param-sugg.stderr
index 363f52d6df8d5..7a9c2f043ac41 100644
--- a/tests/ui/trait-bounds/bad-suggestionf-for-repeated-unsized-bound-127441.stderr
+++ b/tests/ui/trait-bounds/fix-dyn-sized-fn-param-sugg.stderr
@@ -1,41 +1,41 @@
-error[E0203]: type parameter has more than one relaxed default bound, only one is supported
- --> $DIR/bad-suggestionf-for-repeated-unsized-bound-127441.rs:12:12
+error[E0203]: duplicate relaxed `Sized` bounds
+ --> $DIR/fix-dyn-sized-fn-param-sugg.rs:11:12
|
LL | fn foo2<T: ?Sized + ?Sized>(a: T) {}
| ^^^^^^ ^^^^^^
-error[E0203]: type parameter has more than one relaxed default bound, only one is supported
- --> $DIR/bad-suggestionf-for-repeated-unsized-bound-127441.rs:16:12
+error[E0203]: duplicate relaxed `Sized` bounds
+ --> $DIR/fix-dyn-sized-fn-param-sugg.rs:15:12
|
LL | fn foo3<T: ?Sized + ?Sized + Debug>(a: T) {}
| ^^^^^^ ^^^^^^
-error[E0203]: type parameter has more than one relaxed default bound, only one is supported
- --> $DIR/bad-suggestionf-for-repeated-unsized-bound-127441.rs:20:12
+error[E0203]: duplicate relaxed `Sized` bounds
+ --> $DIR/fix-dyn-sized-fn-param-sugg.rs:19:12
|
LL | fn foo4<T: ?Sized + Debug + ?Sized >(a: T) {}
| ^^^^^^ ^^^^^^
-error[E0203]: type parameter has more than one relaxed default bound, only one is supported
- --> $DIR/bad-suggestionf-for-repeated-unsized-bound-127441.rs:27:17
+error[E0203]: duplicate relaxed `Sized` bounds
+ --> $DIR/fix-dyn-sized-fn-param-sugg.rs:26:17
|
LL | fn foo6(_: impl ?Sized + ?Sized) {}
| ^^^^^^ ^^^^^^
-error[E0203]: type parameter has more than one relaxed default bound, only one is supported
- --> $DIR/bad-suggestionf-for-repeated-unsized-bound-127441.rs:31:17
+error[E0203]: duplicate relaxed `Sized` bounds
+ --> $DIR/fix-dyn-sized-fn-param-sugg.rs:30:17
|
LL | fn foo7(_: impl ?Sized + ?Sized + Debug) {}
| ^^^^^^ ^^^^^^
-error[E0203]: type parameter has more than one relaxed default bound, only one is supported
- --> $DIR/bad-suggestionf-for-repeated-unsized-bound-127441.rs:35:17
+error[E0203]: duplicate relaxed `Sized` bounds
+ --> $DIR/fix-dyn-sized-fn-param-sugg.rs:34:17
|
LL | fn foo8(_: impl ?Sized + Debug + ?Sized ) {}
| ^^^^^^ ^^^^^^
error[E0277]: the size for values of type `T` cannot be known at compilation time
- --> $DIR/bad-suggestionf-for-repeated-unsized-bound-127441.rs:9:23
+ --> $DIR/fix-dyn-sized-fn-param-sugg.rs:8:23
|
LL | fn foo1<T: ?Sized>(a: T) {}
| - ^ doesn't have a size known at compile-time
@@ -54,7 +54,7 @@ LL | fn foo1<T: ?Sized>(a: &T) {}
| +
error[E0277]: the size for values of type `T` cannot be known at compilation time
- --> $DIR/bad-suggestionf-for-repeated-unsized-bound-127441.rs:12:32
+ --> $DIR/fix-dyn-sized-fn-param-sugg.rs:11:32
|
LL | fn foo2<T: ?Sized + ?Sized>(a: T) {}
| - ^ doesn't have a size known at compile-time
@@ -73,7 +73,7 @@ LL | fn foo2<T: ?Sized + ?Sized>(a: &T) {}
| +
error[E0277]: the size for values of type `T` cannot be known at compilation time
- --> $DIR/bad-suggestionf-for-repeated-unsized-bound-127441.rs:16:40
+ --> $DIR/fix-dyn-sized-fn-param-sugg.rs:15:40
|
LL | fn foo3<T: ?Sized + ?Sized + Debug>(a: T) {}
| - ^ doesn't have a size known at compile-time
@@ -92,7 +92,7 @@ LL | fn foo3<T: ?Sized + ?Sized + Debug>(a: &T) {}
| +
error[E0277]: the size for values of type `T` cannot be known at compilation time
- --> $DIR/bad-suggestionf-for-repeated-unsized-bound-127441.rs:20:41
+ --> $DIR/fix-dyn-sized-fn-param-sugg.rs:19:41
|
LL | fn foo4<T: ?Sized + Debug + ?Sized >(a: T) {}
| - ^ doesn't have a size known at compile-time
@@ -111,7 +111,7 @@ LL | fn foo4<T: ?Sized + Debug + ?Sized >(a: &T) {}
| +
error[E0277]: the size for values of type `impl ?Sized` cannot be known at compilation time
- --> $DIR/bad-suggestionf-for-repeated-unsized-bound-127441.rs:24:12
+ --> $DIR/fix-dyn-sized-fn-param-sugg.rs:23:12
|
LL | fn foo5(_: impl ?Sized) {}
| ^^^^^^^^^^^
@@ -131,7 +131,7 @@ LL | fn foo5(_: &impl ?Sized) {}
| +
error[E0277]: the size for values of type `impl ?Sized + ?Sized` cannot be known at compilation time
- --> $DIR/bad-suggestionf-for-repeated-unsized-bound-127441.rs:27:12
+ --> $DIR/fix-dyn-sized-fn-param-sugg.rs:26:12
|
LL | fn foo6(_: impl ?Sized + ?Sized) {}
| ^^^^^^^^^^^^^^^^^^^^
@@ -151,7 +151,7 @@ LL | fn foo6(_: &impl ?Sized + ?Sized) {}
| +
error[E0277]: the size for values of type `impl ?Sized + ?Sized + Debug` cannot be known at compilation time
- --> $DIR/bad-suggestionf-for-repeated-unsized-bound-127441.rs:31:12
+ --> $DIR/fix-dyn-sized-fn-param-sugg.rs:30:12
|
LL | fn foo7(_: impl ?Sized + ?Sized + Debug) {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -171,7 +171,7 @@ LL | fn foo7(_: &impl ?Sized + ?Sized + Debug) {}
| +
error[E0277]: the size for values of type `impl ?Sized + Debug + ?Sized` cannot be known at compilation time
- --> $DIR/bad-suggestionf-for-repeated-unsized-bound-127441.rs:35:12
+ --> $DIR/fix-dyn-sized-fn-param-sugg.rs:34:12
|
LL | fn foo8(_: impl ?Sized + Debug + ?Sized ) {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/tests/ui/trait-bounds/maybe-bound-has-path-args.rs b/tests/ui/trait-bounds/maybe-bound-has-path-args.rs
index e5abcae5d219b..14a2667049775 100644
--- a/tests/ui/trait-bounds/maybe-bound-has-path-args.rs
+++ b/tests/ui/trait-bounds/maybe-bound-has-path-args.rs
@@ -2,6 +2,6 @@ trait Trait {}
fn test<T: ?self::<i32>::Trait>() {}
//~^ ERROR type arguments are not allowed on module `maybe_bound_has_path_args`
-//~| ERROR relaxing a default bound only does something for `?Sized`
+//~| ERROR bound modifier `?` can only be applied to `Sized`
fn main() {}
diff --git a/tests/ui/trait-bounds/maybe-bound-has-path-args.stderr b/tests/ui/trait-bounds/maybe-bound-has-path-args.stderr
index dc55b26c9183c..bf968b05af085 100644
--- a/tests/ui/trait-bounds/maybe-bound-has-path-args.stderr
+++ b/tests/ui/trait-bounds/maybe-bound-has-path-args.stderr
@@ -1,4 +1,4 @@
-error: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
+error: bound modifier `?` can only be applied to `Sized`
--> $DIR/maybe-bound-has-path-args.rs:3:12
|
LL | fn test<T: ?self::<i32>::Trait>() {}
diff --git a/tests/ui/trait-bounds/maybe-bound-with-assoc.rs b/tests/ui/trait-bounds/maybe-bound-with-assoc.rs
index 9127c2de16d5e..e123f18474d1c 100644
--- a/tests/ui/trait-bounds/maybe-bound-with-assoc.rs
+++ b/tests/ui/trait-bounds/maybe-bound-with-assoc.rs
@@ -2,11 +2,11 @@ trait HasAssoc {
type Assoc;
}
fn hasassoc<T: ?HasAssoc<Assoc = ()>>() {}
-//~^ ERROR relaxing a default bound
+//~^ ERROR bound modifier `?` can only be applied to `Sized`
trait NoAssoc {}
fn noassoc<T: ?NoAssoc<Missing = ()>>() {}
-//~^ ERROR relaxing a default bound
+//~^ ERROR bound modifier `?` can only be applied to `Sized`
//~| ERROR associated type `Missing` not found for `NoAssoc`
fn main() {}
diff --git a/tests/ui/trait-bounds/maybe-bound-with-assoc.stderr b/tests/ui/trait-bounds/maybe-bound-with-assoc.stderr
index 36a1e0ade2063..b2ae0584aff91 100644
--- a/tests/ui/trait-bounds/maybe-bound-with-assoc.stderr
+++ b/tests/ui/trait-bounds/maybe-bound-with-assoc.stderr
@@ -1,10 +1,10 @@
-error: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
+error: bound modifier `?` can only be applied to `Sized`
--> $DIR/maybe-bound-with-assoc.rs:4:16
|
LL | fn hasassoc<T: ?HasAssoc<Assoc = ()>>() {}
| ^^^^^^^^^^^^^^^^^^^^^
-error: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
+error: bound modifier `?` can only be applied to `Sized`
--> $DIR/maybe-bound-with-assoc.rs:8:15
|
LL | fn noassoc<T: ?NoAssoc<Missing = ()>>() {}
diff --git a/tests/ui/trait-bounds/more_maybe_bounds.rs b/tests/ui/trait-bounds/more_maybe_bounds.rs
new file mode 100644
index 0000000000000..47348b0a0dd78
--- /dev/null
+++ b/tests/ui/trait-bounds/more_maybe_bounds.rs
@@ -0,0 +1,29 @@
+// FIXME(more_maybe_bounds): Even under `more_maybe_bounds` / `-Zexperimental-default-bounds`,
+// trying to relax non-default bounds should still be an error in all contexts! As you can see
+// there are places like supertrait bounds and trait object types where we currently don't perform
+// this check.
+#![feature(auto_traits, more_maybe_bounds, negative_impls)]
+
+trait Trait1 {}
+auto trait Trait2 {}
+
+// FIXME: `?Trait1` should be rejected, `Trait1` isn't marked `#[lang = "default_traitN"]`.
+trait Trait3: ?Trait1 {}
+trait Trait4 where Self: Trait1 {}
+
+// FIXME: `?Trait2` should be rejected, `Trait2` isn't marked `#[lang = "default_traitN"]`.
+fn foo(_: Box<(dyn Trait3 + ?Trait2)>) {}
+fn bar<T: ?Sized + ?Trait2 + ?Trait1 + ?Trait4>(_: &T) {}
+//~^ ERROR bound modifier `?` can only be applied to default traits like `Sized`
+//~| ERROR bound modifier `?` can only be applied to default traits like `Sized`
+//~| ERROR bound modifier `?` can only be applied to default traits like `Sized`
+
+struct S;
+impl !Trait2 for S {}
+impl Trait1 for S {}
+impl Trait3 for S {}
+
+fn main() {
+ foo(Box::new(S));
+ bar(&S);
+}
diff --git a/tests/ui/trait-bounds/more_maybe_bounds.stderr b/tests/ui/trait-bounds/more_maybe_bounds.stderr
new file mode 100644
index 0000000000000..09c9fc311657e
--- /dev/null
+++ b/tests/ui/trait-bounds/more_maybe_bounds.stderr
@@ -0,0 +1,20 @@
+error: bound modifier `?` can only be applied to default traits like `Sized`
+ --> $DIR/more_maybe_bounds.rs:16:20
+ |
+LL | fn bar<T: ?Sized + ?Trait2 + ?Trait1 + ?Trait4>(_: &T) {}
+ | ^^^^^^^
+
+error: bound modifier `?` can only be applied to default traits like `Sized`
+ --> $DIR/more_maybe_bounds.rs:16:30
+ |
+LL | fn bar<T: ?Sized + ?Trait2 + ?Trait1 + ?Trait4>(_: &T) {}
+ | ^^^^^^^
+
+error: bound modifier `?` can only be applied to default traits like `Sized`
+ --> $DIR/more_maybe_bounds.rs:16:40
+ |
+LL | fn bar<T: ?Sized + ?Trait2 + ?Trait1 + ?Trait4>(_: &T) {}
+ | ^^^^^^^
+
+error: aborting due to 3 previous errors
+
diff --git a/tests/ui/traits/const-traits/const-trait-bounds-trait-objects.rs b/tests/ui/traits/const-traits/const-trait-bounds-trait-objects.rs
index ece87529c3e3b..1d1da9b0e3dfc 100644
--- a/tests/ui/traits/const-traits/const-trait-bounds-trait-objects.rs
+++ b/tests/ui/traits/const-traits/const-trait-bounds-trait-objects.rs
@@ -14,5 +14,7 @@ fn main() {
trait NonConst {}
const fn handle(_: &dyn const NonConst) {}
//~^ ERROR const trait bounds are not allowed in trait object types
+//~| ERROR `const` can only be applied to `#[const_trait]` traits
const fn take(_: &dyn [const] NonConst) {}
//~^ ERROR `[const]` is not allowed here
+//~| ERROR `[const]` can only be applied to `#[const_trait]` traits
diff --git a/tests/ui/traits/const-traits/const-trait-bounds-trait-objects.stderr b/tests/ui/traits/const-traits/const-trait-bounds-trait-objects.stderr
index 090555c637791..06e0493024c1b 100644
--- a/tests/ui/traits/const-traits/const-trait-bounds-trait-objects.stderr
+++ b/tests/ui/traits/const-traits/const-trait-bounds-trait-objects.stderr
@@ -19,12 +19,34 @@ LL | const fn handle(_: &dyn const NonConst) {}
| ^^^^^^^^^^^^^^
error: `[const]` is not allowed here
- --> $DIR/const-trait-bounds-trait-objects.rs:17:23
+ --> $DIR/const-trait-bounds-trait-objects.rs:18:23
|
LL | const fn take(_: &dyn [const] NonConst) {}
| ^^^^^^^
|
= note: trait objects cannot have `[const]` trait bounds
-error: aborting due to 4 previous errors
+error: `const` can only be applied to `#[const_trait]` traits
+ --> $DIR/const-trait-bounds-trait-objects.rs:15:25
+ |
+LL | const fn handle(_: &dyn const NonConst) {}
+ | ^^^^^ can't be applied to `NonConst`
+ |
+help: mark `NonConst` as `#[const_trait]` to allow it to have `const` implementations
+ |
+LL | #[const_trait] trait NonConst {}
+ | ++++++++++++++
+
+error: `[const]` can only be applied to `#[const_trait]` traits
+ --> $DIR/const-trait-bounds-trait-objects.rs:18:23
+ |
+LL | const fn take(_: &dyn [const] NonConst) {}
+ | ^^^^^^^ can't be applied to `NonConst`
+ |
+help: mark `NonConst` as `#[const_trait]` to allow it to have `const` implementations
+ |
+LL | #[const_trait] trait NonConst {}
+ | ++++++++++++++
+
+error: aborting due to 6 previous errors
diff --git a/tests/ui/traits/const-traits/mutually-exclusive-trait-bound-modifiers.rs b/tests/ui/traits/const-traits/mutually-exclusive-trait-bound-modifiers.rs
index 5f47778a1404f..2df0a133fd613 100644
--- a/tests/ui/traits/const-traits/mutually-exclusive-trait-bound-modifiers.rs
+++ b/tests/ui/traits/const-traits/mutually-exclusive-trait-bound-modifiers.rs
@@ -2,9 +2,12 @@
const fn maybe_const_maybe<T: [const] ?Sized>() {}
//~^ ERROR `[const]` trait not allowed with `?` trait polarity modifier
+//~| ERROR `[const]` can only be applied to `#[const_trait]` traits
+//~| ERROR `[const]` can only be applied to `#[const_trait]` traits
fn const_maybe<T: const ?Sized>() {}
//~^ ERROR `const` trait not allowed with `?` trait polarity modifier
+//~| ERROR `const` can only be applied to `#[const_trait]` traits
const fn maybe_const_negative<T: [const] !Trait>() {}
//~^ ERROR `[const]` trait not allowed with `!` trait polarity modifier
diff --git a/tests/ui/traits/const-traits/mutually-exclusive-trait-bound-modifiers.stderr b/tests/ui/traits/const-traits/mutually-exclusive-trait-bound-modifiers.stderr
index 429131f905f0e..d25c0d2d82bb6 100644
--- a/tests/ui/traits/const-traits/mutually-exclusive-trait-bound-modifiers.stderr
+++ b/tests/ui/traits/const-traits/mutually-exclusive-trait-bound-modifiers.stderr
@@ -7,7 +7,7 @@ LL | const fn maybe_const_maybe<T: [const] ?Sized>() {}
| there is not a well-defined meaning for a `[const] ?` trait
error: `const` trait not allowed with `?` trait polarity modifier
- --> $DIR/mutually-exclusive-trait-bound-modifiers.rs:6:25
+ --> $DIR/mutually-exclusive-trait-bound-modifiers.rs:8:25
|
LL | fn const_maybe<T: const ?Sized>() {}
| ----- ^
@@ -15,7 +15,7 @@ LL | fn const_maybe<T: const ?Sized>() {}
| there is not a well-defined meaning for a `const ?` trait
error: `[const]` trait not allowed with `!` trait polarity modifier
- --> $DIR/mutually-exclusive-trait-bound-modifiers.rs:9:42
+ --> $DIR/mutually-exclusive-trait-bound-modifiers.rs:12:42
|
LL | const fn maybe_const_negative<T: [const] !Trait>() {}
| ------- ^
@@ -23,7 +23,7 @@ LL | const fn maybe_const_negative<T: [const] !Trait>() {}
| there is not a well-defined meaning for a `[const] !` trait
error: `const` trait not allowed with `!` trait polarity modifier
- --> $DIR/mutually-exclusive-trait-bound-modifiers.rs:13:28
+ --> $DIR/mutually-exclusive-trait-bound-modifiers.rs:16:28
|
LL | fn const_negative<T: const !Trait>() {}
| ----- ^
@@ -31,16 +31,44 @@ LL | fn const_negative<T: const !Trait>() {}
| there is not a well-defined meaning for a `const !` trait
error: negative bounds are not supported
- --> $DIR/mutually-exclusive-trait-bound-modifiers.rs:9:42
+ --> $DIR/mutually-exclusive-trait-bound-modifiers.rs:12:42
|
LL | const fn maybe_const_negative<T: [const] !Trait>() {}
| ^
error: negative bounds are not supported
- --> $DIR/mutually-exclusive-trait-bound-modifiers.rs:13:28
+ --> $DIR/mutually-exclusive-trait-bound-modifiers.rs:16:28
|
LL | fn const_negative<T: const !Trait>() {}
| ^
-error: aborting due to 6 previous errors
+error: `[const]` can only be applied to `#[const_trait]` traits
+ --> $DIR/mutually-exclusive-trait-bound-modifiers.rs:3:31
+ |
+LL | const fn maybe_const_maybe<T: [const] ?Sized>() {}
+ | ^^^^^^^ can't be applied to `Sized`
+ |
+note: `Sized` can't be used with `[const]` because it isn't annotated with `#[const_trait]`
+ --> $SRC_DIR/core/src/marker.rs:LL:COL
+
+error: `[const]` can only be applied to `#[const_trait]` traits
+ --> $DIR/mutually-exclusive-trait-bound-modifiers.rs:3:31
+ |
+LL | const fn maybe_const_maybe<T: [const] ?Sized>() {}
+ | ^^^^^^^ can't be applied to `Sized`
+ |
+note: `Sized` can't be used with `[const]` because it isn't annotated with `#[const_trait]`
+ --> $SRC_DIR/core/src/marker.rs:LL:COL
+ = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+error: `const` can only be applied to `#[const_trait]` traits
+ --> $DIR/mutually-exclusive-trait-bound-modifiers.rs:8:19
+ |
+LL | fn const_maybe<T: const ?Sized>() {}
+ | ^^^^^ can't be applied to `Sized`
+ |
+note: `Sized` can't be used with `const` because it isn't annotated with `#[const_trait]`
+ --> $SRC_DIR/core/src/marker.rs:LL:COL
+
+error: aborting due to 9 previous errors
diff --git a/tests/ui/traits/default_auto_traits/maybe-bounds-in-dyn-traits.rs b/tests/ui/traits/default_auto_traits/maybe-bounds-in-dyn-traits.rs
index 5069cd256b277..e7cca41a47eab 100644
--- a/tests/ui/traits/default_auto_traits/maybe-bounds-in-dyn-traits.rs
+++ b/tests/ui/traits/default_auto_traits/maybe-bounds-in-dyn-traits.rs
@@ -64,4 +64,8 @@ fn main() {
x.leak_foo();
//~^ ERROR the trait bound `dyn Trait: Leak` is not satisfied
x.maybe_leak_foo();
+ // Ensure that we validate the generic args of relaxed bounds in trait object types.
+ let _: dyn Trait + ?Leak<(), Undefined = ()>;
+ //~^ ERROR trait takes 0 generic arguments but 1 generic argument was supplied
+ //~| ERROR associated type `Undefined` not found for `Leak`
}
diff --git a/tests/ui/traits/default_auto_traits/maybe-bounds-in-dyn-traits.stderr b/tests/ui/traits/default_auto_traits/maybe-bounds-in-dyn-traits.stderr
index 48745e40268d4..350233b7cbe9d 100644
--- a/tests/ui/traits/default_auto_traits/maybe-bounds-in-dyn-traits.stderr
+++ b/tests/ui/traits/default_auto_traits/maybe-bounds-in-dyn-traits.stderr
@@ -18,6 +18,27 @@ note: required by a bound in `Trait::leak_foo`
LL | fn leak_foo(&self) {}
| ^^^^^^^^^^^^^^^^^^^^^ required by this bound in `Trait::leak_foo`
-error: aborting due to 2 previous errors
+error[E0107]: trait takes 0 generic arguments but 1 generic argument was supplied
+ --> $DIR/maybe-bounds-in-dyn-traits.rs:68:25
+ |
+LL | let _: dyn Trait + ?Leak<(), Undefined = ()>;
+ | ^^^^-------------------- help: remove the unnecessary generics
+ | |
+ | expected 0 generic arguments
+ |
+note: trait defined here, with 0 generic parameters
+ --> $DIR/maybe-bounds-in-dyn-traits.rs:44:12
+ |
+LL | auto trait Leak {}
+ | ^^^^
+
+error[E0220]: associated type `Undefined` not found for `Leak`
+ --> $DIR/maybe-bounds-in-dyn-traits.rs:68:34
+ |
+LL | let _: dyn Trait + ?Leak<(), Undefined = ()>;
+ | ^^^^^^^^^ associated type `Undefined` not found
+
+error: aborting due to 4 previous errors
-For more information about this error, try `rustc --explain E0277`.
+Some errors have detailed explanations: E0107, E0220, E0277.
+For more information about an error, try `rustc --explain E0107`.
diff --git a/tests/ui/traits/maybe-polarity-pass.rs b/tests/ui/traits/maybe-polarity-pass.rs
deleted file mode 100644
index 1ccd52bc1694a..0000000000000
--- a/tests/ui/traits/maybe-polarity-pass.rs
+++ /dev/null
@@ -1,25 +0,0 @@
-#![feature(auto_traits)]
-#![feature(more_maybe_bounds)]
-#![feature(negative_impls)]
-
-trait Trait1 {}
-auto trait Trait2 {}
-
-trait Trait3 : ?Trait1 {}
-trait Trait4 where Self: Trait1 {}
-
-fn foo(_: Box<(dyn Trait3 + ?Trait2)>) {}
-fn bar<T: ?Sized + ?Trait2 + ?Trait1 + ?Trait4>(_: &T) {}
-//~^ ERROR relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
-//~| ERROR relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
-//~| ERROR relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
-
-struct S;
-impl !Trait2 for S {}
-impl Trait1 for S {}
-impl Trait3 for S {}
-
-fn main() {
- foo(Box::new(S));
- bar(&S);
-}
diff --git a/tests/ui/traits/maybe-polarity-pass.stderr b/tests/ui/traits/maybe-polarity-pass.stderr
deleted file mode 100644
index 1f378dd665ae6..0000000000000
--- a/tests/ui/traits/maybe-polarity-pass.stderr
+++ /dev/null
@@ -1,20 +0,0 @@
-error: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
- --> $DIR/maybe-polarity-pass.rs:12:20
- |
-LL | fn bar<T: ?Sized + ?Trait2 + ?Trait1 + ?Trait4>(_: &T) {}
- | ^^^^^^^
-
-error: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
- --> $DIR/maybe-polarity-pass.rs:12:30
- |
-LL | fn bar<T: ?Sized + ?Trait2 + ?Trait1 + ?Trait4>(_: &T) {}
- | ^^^^^^^
-
-error: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
- --> $DIR/maybe-polarity-pass.rs:12:40
- |
-LL | fn bar<T: ?Sized + ?Trait2 + ?Trait1 + ?Trait4>(_: &T) {}
- | ^^^^^^^
-
-error: aborting due to 3 previous errors
-
diff --git a/tests/ui/traits/maybe-polarity-repeated.rs b/tests/ui/traits/maybe-polarity-repeated.rs
deleted file mode 100644
index fd1ef567b3eab..0000000000000
--- a/tests/ui/traits/maybe-polarity-repeated.rs
+++ /dev/null
@@ -1,9 +0,0 @@
-#![feature(more_maybe_bounds)]
-
-trait Trait {}
-fn foo<T: ?Trait + ?Trait>(_: T) {}
-//~^ ERROR type parameter has more than one relaxed default bound, only one is supported
-//~| ERROR relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
-//~| ERROR relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
-
-fn main() {}
diff --git a/tests/ui/traits/maybe-polarity-repeated.stderr b/tests/ui/traits/maybe-polarity-repeated.stderr
deleted file mode 100644
index 4fa1dc45bda85..0000000000000
--- a/tests/ui/traits/maybe-polarity-repeated.stderr
+++ /dev/null
@@ -1,21 +0,0 @@
-error[E0203]: type parameter has more than one relaxed default bound, only one is supported
- --> $DIR/maybe-polarity-repeated.rs:4:11
- |
-LL | fn foo<T: ?Trait + ?Trait>(_: T) {}
- | ^^^^^^ ^^^^^^
-
-error: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
- --> $DIR/maybe-polarity-repeated.rs:4:11
- |
-LL | fn foo<T: ?Trait + ?Trait>(_: T) {}
- | ^^^^^^
-
-error: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
- --> $DIR/maybe-polarity-repeated.rs:4:20
- |
-LL | fn foo<T: ?Trait + ?Trait>(_: T) {}
- | ^^^^^^
-
-error: aborting due to 3 previous errors
-
-For more information about this error, try `rustc --explain E0203`.
diff --git a/tests/ui/traits/maybe-trait-bounds-forbidden-locations.rs b/tests/ui/traits/maybe-trait-bounds-forbidden-locations.rs
deleted file mode 100644
index 04963c98765e9..0000000000000
--- a/tests/ui/traits/maybe-trait-bounds-forbidden-locations.rs
+++ /dev/null
@@ -1,18 +0,0 @@
-//! Test that ?Trait bounds are forbidden in supertraits and trait object types.
-//!
-//! While `?Sized` and other maybe bounds are allowed in type parameter bounds and where clauses,
-//! they are explicitly forbidden in certain syntactic positions:
-//! - As supertraits in trait definitions
-//! - In trait object type expressions
-//!
-//! See https://github.com/rust-lang/rust/issues/20503
-
-trait Tr: ?Sized {}
-//~^ ERROR `?Trait` is not permitted in supertraits
-
-type A1 = dyn Tr + (?Sized);
-//~^ ERROR `?Trait` is not permitted in trait object types
-type A2 = dyn for<'a> Tr + (?Sized);
-//~^ ERROR `?Trait` is not permitted in trait object types
-
-fn main() {}
diff --git a/tests/ui/traits/maybe-trait-bounds-forbidden-locations.stderr b/tests/ui/traits/maybe-trait-bounds-forbidden-locations.stderr
deleted file mode 100644
index bd0baa580bdf5..0000000000000
--- a/tests/ui/traits/maybe-trait-bounds-forbidden-locations.stderr
+++ /dev/null
@@ -1,31 +0,0 @@
-error[E0658]: `?Trait` is not permitted in supertraits
- --> $DIR/maybe-trait-bounds-forbidden-locations.rs:10:11
- |
-LL | trait Tr: ?Sized {}
- | ^^^^^^
- |
- = note: traits are `?Sized` by default
- = help: add `#![feature(more_maybe_bounds)]` 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[E0658]: `?Trait` is not permitted in trait object types
- --> $DIR/maybe-trait-bounds-forbidden-locations.rs:13:20
- |
-LL | type A1 = dyn Tr + (?Sized);
- | ^^^^^^^^
- |
- = help: add `#![feature(more_maybe_bounds)]` 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[E0658]: `?Trait` is not permitted in trait object types
- --> $DIR/maybe-trait-bounds-forbidden-locations.rs:15:28
- |
-LL | type A2 = dyn for<'a> Tr + (?Sized);
- | ^^^^^^^^
- |
- = help: add `#![feature(more_maybe_bounds)]` 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 3 previous errors
-
-For more information about this error, try `rustc --explain E0658`.
diff --git a/tests/ui/traits/wf-object/maybe-bound.rs b/tests/ui/traits/wf-object/maybe-bound.rs
deleted file mode 100644
index 17771e976ef3b..0000000000000
--- a/tests/ui/traits/wf-object/maybe-bound.rs
+++ /dev/null
@@ -1,18 +0,0 @@
-// Test that `dyn ... + ?Sized + ...` is okay (though `?Sized` has no effect in trait objects).
-
-trait Foo {}
-
-type _0 = dyn ?Sized + Foo;
-//~^ ERROR `?Trait` is not permitted in trait object types
-
-type _1 = dyn Foo + ?Sized;
-//~^ ERROR `?Trait` is not permitted in trait object types
-
-type _2 = dyn Foo + ?Sized + ?Sized;
-//~^ ERROR `?Trait` is not permitted in trait object types
-//~| ERROR `?Trait` is not permitted in trait object types
-
-type _3 = dyn ?Sized + Foo;
-//~^ ERROR `?Trait` is not permitted in trait object types
-
-fn main() {}
diff --git a/tests/ui/traits/wf-object/maybe-bound.stderr b/tests/ui/traits/wf-object/maybe-bound.stderr
deleted file mode 100644
index be7afabd0d01d..0000000000000
--- a/tests/ui/traits/wf-object/maybe-bound.stderr
+++ /dev/null
@@ -1,48 +0,0 @@
-error[E0658]: `?Trait` is not permitted in trait object types
- --> $DIR/maybe-bound.rs:5:15
- |
-LL | type _0 = dyn ?Sized + Foo;
- | ^^^^^^
- |
- = help: add `#![feature(more_maybe_bounds)]` 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[E0658]: `?Trait` is not permitted in trait object types
- --> $DIR/maybe-bound.rs:8:21
- |
-LL | type _1 = dyn Foo + ?Sized;
- | ^^^^^^
- |
- = help: add `#![feature(more_maybe_bounds)]` 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[E0658]: `?Trait` is not permitted in trait object types
- --> $DIR/maybe-bound.rs:11:21
- |
-LL | type _2 = dyn Foo + ?Sized + ?Sized;
- | ^^^^^^
- |
- = help: add `#![feature(more_maybe_bounds)]` 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[E0658]: `?Trait` is not permitted in trait object types
- --> $DIR/maybe-bound.rs:11:30
- |
-LL | type _2 = dyn Foo + ?Sized + ?Sized;
- | ^^^^^^
- |
- = help: add `#![feature(more_maybe_bounds)]` 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[E0658]: `?Trait` is not permitted in trait object types
- --> $DIR/maybe-bound.rs:15:15
- |
-LL | type _3 = dyn ?Sized + Foo;
- | ^^^^^^
- |
- = help: add `#![feature(more_maybe_bounds)]` 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 5 previous errors
-
-For more information about this error, try `rustc --explain E0658`.
diff --git a/tests/ui/traits/wf-object/only-maybe-bound.rs b/tests/ui/traits/wf-object/only-maybe-bound.rs
index 3e6db3e997c9b..96360e0331cdb 100644
--- a/tests/ui/traits/wf-object/only-maybe-bound.rs
+++ b/tests/ui/traits/wf-object/only-maybe-bound.rs
@@ -2,6 +2,6 @@
type _0 = dyn ?Sized;
//~^ ERROR at least one trait is required for an object type [E0224]
-//~| ERROR ?Trait` is not permitted in trait object types
+//~| ERROR relaxed bounds are not permitted in trait object types
fn main() {}
diff --git a/tests/ui/traits/wf-object/only-maybe-bound.stderr b/tests/ui/traits/wf-object/only-maybe-bound.stderr
index 26269476eaaee..d52728e209ec4 100644
--- a/tests/ui/traits/wf-object/only-maybe-bound.stderr
+++ b/tests/ui/traits/wf-object/only-maybe-bound.stderr
@@ -1,4 +1,4 @@
-error[E0658]: `?Trait` is not permitted in trait object types
+error[E0658]: relaxed bounds are not permitted in trait object types
--> $DIR/only-maybe-bound.rs:3:15
|
LL | type _0 = dyn ?Sized;
diff --git a/tests/ui/unsized/maybe-bounds-where.rs b/tests/ui/unsized/maybe-bounds-where.rs
deleted file mode 100644
index 4c4141631a7c5..0000000000000
--- a/tests/ui/unsized/maybe-bounds-where.rs
+++ /dev/null
@@ -1,28 +0,0 @@
-struct S1<T>(T) where (T): ?Sized;
-//~^ ERROR `?Trait` bounds are only permitted at the point where a type parameter is declared
-
-struct S2<T>(T) where u8: ?Sized;
-//~^ ERROR `?Trait` bounds are only permitted at the point where a type parameter is declared
-
-struct S3<T>(T) where &'static T: ?Sized;
-//~^ ERROR `?Trait` bounds are only permitted at the point where a type parameter is declared
-
-trait Trait<'a> {}
-
-struct S4<T>(T) where for<'a> T: ?Trait<'a>;
-//~^ ERROR `?Trait` bounds are only permitted at the point where a type parameter is declared
-//~| ERROR relaxing a default bound only does something for `?Sized`
-
-struct S5<T>(*const T) where T: ?Trait<'static> + ?Sized;
-//~^ ERROR type parameter has more than one relaxed default bound
-//~| ERROR relaxing a default bound only does something for `?Sized`
-
-impl<T> S1<T> {
- fn f() where T: ?Sized {}
- //~^ ERROR `?Trait` bounds are only permitted at the point where a type parameter is declared
-}
-
-fn main() {
- let u = vec![1, 2, 3];
- let _s: S5<[u8]> = S5(&u[..]); // OK
-}
diff --git a/tests/ui/unsized/maybe-bounds-where.stderr b/tests/ui/unsized/maybe-bounds-where.stderr
deleted file mode 100644
index fb6d37c29660a..0000000000000
--- a/tests/ui/unsized/maybe-bounds-where.stderr
+++ /dev/null
@@ -1,70 +0,0 @@
-error[E0658]: `?Trait` bounds are only permitted at the point where a type parameter is declared
- --> $DIR/maybe-bounds-where.rs:1:28
- |
-LL | struct S1<T>(T) where (T): ?Sized;
- | ^^^^^^
- |
- = help: add `#![feature(more_maybe_bounds)]` 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[E0658]: `?Trait` bounds are only permitted at the point where a type parameter is declared
- --> $DIR/maybe-bounds-where.rs:4:27
- |
-LL | struct S2<T>(T) where u8: ?Sized;
- | ^^^^^^
- |
- = help: add `#![feature(more_maybe_bounds)]` 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[E0658]: `?Trait` bounds are only permitted at the point where a type parameter is declared
- --> $DIR/maybe-bounds-where.rs:7:35
- |
-LL | struct S3<T>(T) where &'static T: ?Sized;
- | ^^^^^^
- |
- = help: add `#![feature(more_maybe_bounds)]` 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[E0658]: `?Trait` bounds are only permitted at the point where a type parameter is declared
- --> $DIR/maybe-bounds-where.rs:12:34
- |
-LL | struct S4<T>(T) where for<'a> T: ?Trait<'a>;
- | ^^^^^^^^^^
- |
- = help: add `#![feature(more_maybe_bounds)]` 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[E0658]: `?Trait` bounds are only permitted at the point where a type parameter is declared
- --> $DIR/maybe-bounds-where.rs:21:21
- |
-LL | fn f() where T: ?Sized {}
- | ^^^^^^
- |
- = help: add `#![feature(more_maybe_bounds)]` 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: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
- --> $DIR/maybe-bounds-where.rs:12:34
- |
-LL | struct S4<T>(T) where for<'a> T: ?Trait<'a>;
- | ^^^^^^^^^^
-
-error[E0203]: type parameter has more than one relaxed default bound, only one is supported
- --> $DIR/maybe-bounds-where.rs:16:33
- |
-LL | struct S5<T>(*const T) where T: ?Trait<'static> + ?Sized;
- | ^^^^^^^^^^^^^^^ ^^^^^^
- |
- = help: add `#![feature(more_maybe_bounds)]` 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: relaxing a default bound only does something for `?Sized`; all other traits are not bound by default
- --> $DIR/maybe-bounds-where.rs:16:33
- |
-LL | struct S5<T>(*const T) where T: ?Trait<'static> + ?Sized;
- | ^^^^^^^^^^^^^^^
-
-error: aborting due to 8 previous errors
-
-Some errors have detailed explanations: E0203, E0658.
-For more information about an error, try `rustc --explain E0203`.
diff --git a/tests/ui/unsized/relaxed-bounds-invalid-places.rs b/tests/ui/unsized/relaxed-bounds-invalid-places.rs
new file mode 100644
index 0000000000000..b8eda1e7786b5
--- /dev/null
+++ b/tests/ui/unsized/relaxed-bounds-invalid-places.rs
@@ -0,0 +1,34 @@
+// Test various places where relaxed bounds are not permitted.
+//
+// Relaxed bounds are only permitted inside impl-Trait, assoc ty item bounds and
+// on type params defined by the closest item.
+
+struct S1<T>(T) where (T): ?Sized; //~ ERROR this relaxed bound is not permitted here
+
+struct S2<T>(T) where u8: ?Sized; //~ ERROR this relaxed bound is not permitted here
+
+struct S3<T>(T) where &'static T: ?Sized; //~ ERROR this relaxed bound is not permitted here
+
+trait Trait<'a> {}
+
+struct S4<T>(T) where for<'a> T: ?Trait<'a>;
+//~^ ERROR this relaxed bound is not permitted here
+//~| ERROR bound modifier `?` can only be applied to `Sized`
+
+struct S5<T>(*const T) where T: ?Trait<'static> + ?Sized;
+//~^ ERROR bound modifier `?` can only be applied to `Sized`
+
+impl<T> S1<T> {
+ fn f() where T: ?Sized {} //~ ERROR this relaxed bound is not permitted here
+}
+
+trait Tr: ?Sized {} //~ ERROR relaxed bounds are not permitted in supertrait bounds
+
+// Test that relaxed `Sized` bounds are rejected in trait object types:
+
+type O1 = dyn Tr + ?Sized; //~ ERROR relaxed bounds are not permitted in trait object types
+type O2 = dyn ?Sized + ?Sized + Tr;
+//~^ ERROR relaxed bounds are not permitted in trait object types
+//~| ERROR relaxed bounds are not permitted in trait object types
+
+fn main() {}
diff --git a/tests/ui/unsized/relaxed-bounds-invalid-places.stderr b/tests/ui/unsized/relaxed-bounds-invalid-places.stderr
new file mode 100644
index 0000000000000..46a709f2e9e87
--- /dev/null
+++ b/tests/ui/unsized/relaxed-bounds-invalid-places.stderr
@@ -0,0 +1,102 @@
+error[E0658]: this relaxed bound is not permitted here
+ --> $DIR/relaxed-bounds-invalid-places.rs:6:28
+ |
+LL | struct S1<T>(T) where (T): ?Sized;
+ | ^^^^^^
+ |
+ = help: add `#![feature(more_maybe_bounds)]` to the crate attributes to enable
+ = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
+ = note: in this context, relaxed bounds are only allowed on type parameters defined by the closest item
+
+error[E0658]: this relaxed bound is not permitted here
+ --> $DIR/relaxed-bounds-invalid-places.rs:8:27
+ |
+LL | struct S2<T>(T) where u8: ?Sized;
+ | ^^^^^^
+ |
+ = help: add `#![feature(more_maybe_bounds)]` to the crate attributes to enable
+ = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
+ = note: in this context, relaxed bounds are only allowed on type parameters defined by the closest item
+
+error[E0658]: this relaxed bound is not permitted here
+ --> $DIR/relaxed-bounds-invalid-places.rs:10:35
+ |
+LL | struct S3<T>(T) where &'static T: ?Sized;
+ | ^^^^^^
+ |
+ = help: add `#![feature(more_maybe_bounds)]` to the crate attributes to enable
+ = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
+ = note: in this context, relaxed bounds are only allowed on type parameters defined by the closest item
+
+error[E0658]: this relaxed bound is not permitted here
+ --> $DIR/relaxed-bounds-invalid-places.rs:14:34
+ |
+LL | struct S4<T>(T) where for<'a> T: ?Trait<'a>;
+ | ^^^^^^^^^^
+ |
+ = help: add `#![feature(more_maybe_bounds)]` to the crate attributes to enable
+ = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
+ = note: in this context, relaxed bounds are only allowed on type parameters defined by the closest item
+
+error[E0658]: this relaxed bound is not permitted here
+ --> $DIR/relaxed-bounds-invalid-places.rs:22:21
+ |
+LL | fn f() where T: ?Sized {}
+ | ^^^^^^
+ |
+ = help: add `#![feature(more_maybe_bounds)]` to the crate attributes to enable
+ = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
+ = note: in this context, relaxed bounds are only allowed on type parameters defined by the closest item
+
+error[E0658]: relaxed bounds are not permitted in supertrait bounds
+ --> $DIR/relaxed-bounds-invalid-places.rs:25:11
+ |
+LL | trait Tr: ?Sized {}
+ | ^^^^^^
+ |
+ = help: add `#![feature(more_maybe_bounds)]` to the crate attributes to enable
+ = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
+ = note: traits are `?Sized` by default
+
+error[E0658]: relaxed bounds are not permitted in trait object types
+ --> $DIR/relaxed-bounds-invalid-places.rs:29:20
+ |
+LL | type O1 = dyn Tr + ?Sized;
+ | ^^^^^^
+ |
+ = help: add `#![feature(more_maybe_bounds)]` 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[E0658]: relaxed bounds are not permitted in trait object types
+ --> $DIR/relaxed-bounds-invalid-places.rs:30:15
+ |
+LL | type O2 = dyn ?Sized + ?Sized + Tr;
+ | ^^^^^^
+ |
+ = help: add `#![feature(more_maybe_bounds)]` 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[E0658]: relaxed bounds are not permitted in trait object types
+ --> $DIR/relaxed-bounds-invalid-places.rs:30:24
+ |
+LL | type O2 = dyn ?Sized + ?Sized + Tr;
+ | ^^^^^^
+ |
+ = help: add `#![feature(more_maybe_bounds)]` 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: bound modifier `?` can only be applied to `Sized`
+ --> $DIR/relaxed-bounds-invalid-places.rs:14:34
+ |
+LL | struct S4<T>(T) where for<'a> T: ?Trait<'a>;
+ | ^^^^^^^^^^
+
+error: bound modifier `?` can only be applied to `Sized`
+ --> $DIR/relaxed-bounds-invalid-places.rs:18:33
+ |
+LL | struct S5<T>(*const T) where T: ?Trait<'static> + ?Sized;
+ | ^^^^^^^^^^^^^^^
+
+error: aborting due to 11 previous errors
+
+For more information about this error, try `rustc --explain E0658`.