Merge pull request rust-lang#4478 from rust-lang/rustup-2025-07-19

Automatic Rustup

Author: oli-obk

compiler/rustc_attr_data_structures/src/attributes.rs

@@ -110,6 +110,22 @@ pub enum DeprecatedSince {
     Err,
 }
 
+#[derive(
+    Copy,
+    Debug,
+    Eq,
+    PartialEq,
+    Encodable,
+    Decodable,
+    Clone,
+    HashStable_Generic,
+    PrintAttribute
+)]
+pub enum CoverageStatus {
+    On,
+    Off,
+}
+
 impl Deprecation {
     /// Whether an item marked with #[deprecated(since = "X")] is currently
     /// deprecated (i.e., whether X is not greater than the current rustc
@@ -274,6 +290,9 @@ pub enum AttributeKind {
     /// Represents `#[const_trait]`.
     ConstTrait(Span),
 
+    /// Represents `#[coverage]`.
+    Coverage(Span, CoverageStatus),
+
     ///Represents `#[rustc_deny_explicit_impl]`.
     DenyExplicitImpl(Span),
 

compiler/rustc_attr_data_structures/src/encode_cross_crate.rs

@@ -28,6 +28,7 @@ impl AttributeKind {
             ConstStability { .. } => Yes,
             ConstStabilityIndirect => No,
             ConstTrait(..) => No,
+            Coverage(..) => No,
             DenyExplicitImpl(..) => No,
             Deprecation { .. } => Yes,
             DoNotImplementViaObject(..) => No,

compiler/rustc_attr_data_structures/src/lib.rs

@@ -24,7 +24,7 @@ use rustc_ast::token::CommentKind;
 use rustc_ast::{AttrStyle, IntTy, UintTy};
 use rustc_ast_pretty::pp::Printer;
 use rustc_span::hygiene::Transparency;
-use rustc_span::{Span, Symbol};
+use rustc_span::{ErrorGuaranteed, Span, Symbol};
 pub use stability::*;
 use thin_vec::ThinVec;
 pub use version::*;
@@ -170,7 +170,7 @@ macro_rules! print_tup {
 }
 
 print_tup!(A B C D E F G H);
-print_skip!(Span, ());
+print_skip!(Span, (), ErrorGuaranteed);
 print_disp!(u16, bool, NonZero<u32>);
 print_debug!(Symbol, UintTy, IntTy, Align, AttrStyle, CommentKind, Transparency);
 

compiler/rustc_attr_data_structures/src/stability.rs

@@ -1,7 +1,7 @@
 use std::num::NonZero;
 
 use rustc_macros::{Decodable, Encodable, HashStable_Generic, PrintAttribute};
-use rustc_span::{Symbol, sym};
+use rustc_span::{ErrorGuaranteed, Symbol, sym};
 
 use crate::{PrintAttribute, RustcVersion};
 
@@ -153,7 +153,7 @@ pub enum StableSince {
     /// Stabilized in the upcoming version, whatever number that is.
     Current,
     /// Failed to parse a stabilization version.
-    Err,
+    Err(ErrorGuaranteed),
 }
 
 impl StabilityLevel {

compiler/rustc_attr_parsing/src/attributes/codegen_attrs.rs

@@ -1,4 +1,4 @@
-use rustc_attr_data_structures::{AttributeKind, OptimizeAttr, UsedBy};
+use rustc_attr_data_structures::{AttributeKind, CoverageStatus, OptimizeAttr, UsedBy};
 use rustc_feature::{AttributeTemplate, template};
 use rustc_session::parse::feature_err;
 use rustc_span::{Span, Symbol, sym};
@@ -52,6 +52,45 @@ impl<S: Stage> NoArgsAttributeParser<S> for ColdParser {
     const CREATE: fn(Span) -> AttributeKind = AttributeKind::Cold;
 }
 
+pub(crate) struct CoverageParser;
+
+impl<S: Stage> SingleAttributeParser<S> for CoverageParser {
+    const PATH: &[Symbol] = &[sym::coverage];
+    const ATTRIBUTE_ORDER: AttributeOrder = AttributeOrder::KeepOutermost;
+    const ON_DUPLICATE: OnDuplicate<S> = OnDuplicate::Error;
+    const TEMPLATE: AttributeTemplate = template!(OneOf: &[sym::off, sym::on]);
+
+    fn convert(cx: &mut AcceptContext<'_, '_, S>, args: &ArgParser<'_>) -> Option<AttributeKind> {
+        let Some(args) = args.list() else {
+            cx.expected_specific_argument_and_list(cx.attr_span, vec!["on", "off"]);
+            return None;
+        };
+
+        let Some(arg) = args.single() else {
+            cx.expected_single_argument(args.span);
+            return None;
+        };
+
+        let fail_incorrect_argument = |span| cx.expected_specific_argument(span, vec!["on", "off"]);
+
+        let Some(arg) = arg.meta_item() else {
+            fail_incorrect_argument(args.span);
+            return None;
+        };
+
+        let status = match arg.path().word_sym() {
+            Some(sym::off) => CoverageStatus::Off,
+            Some(sym::on) => CoverageStatus::On,
+            None | Some(_) => {
+                fail_incorrect_argument(arg.span());
+                return None;
+            }
+        };
+
+        Some(AttributeKind::Coverage(cx.attr_span, status))
+    }
+}
+
 pub(crate) struct ExportNameParser;
 
 impl<S: Stage> SingleAttributeParser<S> for ExportNameParser {

compiler/rustc_attr_parsing/src/attributes/stability.rs

@@ -292,12 +292,12 @@ pub(crate) fn parse_stability<S: Stage>(
         } else if let Some(version) = parse_version(since) {
             StableSince::Version(version)
         } else {
-            cx.emit_err(session_diagnostics::InvalidSince { span: cx.attr_span });
-            StableSince::Err
+            let err = cx.emit_err(session_diagnostics::InvalidSince { span: cx.attr_span });
+            StableSince::Err(err)
         }
     } else {
-        cx.emit_err(session_diagnostics::MissingSince { span: cx.attr_span });
-        StableSince::Err
+        let err = cx.emit_err(session_diagnostics::MissingSince { span: cx.attr_span });
+        StableSince::Err(err)
     };
 
     match feature {

compiler/rustc_attr_parsing/src/context.rs

@@ -17,8 +17,9 @@ use crate::attributes::allow_unstable::{
     AllowConstFnUnstableParser, AllowInternalUnstableParser, UnstableFeatureBoundParser,
 };
 use crate::attributes::codegen_attrs::{
-    ColdParser, ExportNameParser, NakedParser, NoMangleParser, OmitGdbPrettyPrinterSectionParser,
-    OptimizeParser, TargetFeatureParser, TrackCallerParser, UsedParser,
+    ColdParser, CoverageParser, ExportNameParser, NakedParser, NoMangleParser,
+    OmitGdbPrettyPrinterSectionParser, OptimizeParser, TargetFeatureParser, TrackCallerParser,
+    UsedParser,
 };
 use crate::attributes::confusables::ConfusablesParser;
 use crate::attributes::deprecation::DeprecationParser;
@@ -139,6 +140,7 @@ attribute_parsers!(
         // tidy-alphabetical-end
 
         // tidy-alphabetical-start
+        Single<CoverageParser>,
         Single<DeprecationParser>,
         Single<DummyParser>,
         Single<ExportNameParser>,
@@ -452,6 +454,25 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
             reason: AttributeParseErrorReason::ExpectedSpecificArgument {
                 possibilities,
                 strings: false,
+                list: false,
+            },
+        })
+    }
+
+    pub(crate) fn expected_specific_argument_and_list(
+        &self,
+        span: Span,
+        possibilities: Vec<&'static str>,
+    ) -> ErrorGuaranteed {
+        self.emit_err(AttributeParseError {
+            span,
+            attr_span: self.attr_span,
+            template: self.template.clone(),
+            attribute: self.attr_path.clone(),
+            reason: AttributeParseErrorReason::ExpectedSpecificArgument {
+                possibilities,
+                strings: false,
+                list: true,
             },
         })
     }
@@ -469,6 +490,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
             reason: AttributeParseErrorReason::ExpectedSpecificArgument {
                 possibilities,
                 strings: true,
+                list: false,
             },
         })
     }

compiler/rustc_attr_parsing/src/session_diagnostics.rs

@@ -533,15 +533,22 @@ pub(crate) struct LinkOrdinalOutOfRange {
 
 pub(crate) enum AttributeParseErrorReason {
     ExpectedNoArgs,
-    ExpectedStringLiteral { byte_string: Option<Span> },
+    ExpectedStringLiteral {
+        byte_string: Option<Span>,
+    },
     ExpectedIntegerLiteral,
     ExpectedAtLeastOneArgument,
     ExpectedSingleArgument,
     ExpectedList,
     UnexpectedLiteral,
     ExpectedNameValue(Option<Symbol>),
     DuplicateKey(Symbol),
-    ExpectedSpecificArgument { possibilities: Vec<&'static str>, strings: bool },
+    ExpectedSpecificArgument {
+        possibilities: Vec<&'static str>,
+        strings: bool,
+        /// Should we tell the user to write a list when they didn't?
+        list: bool,
+    },
 }
 
 pub(crate) struct AttributeParseError {
@@ -615,7 +622,11 @@ impl<'a, G: EmissionGuarantee> Diagnostic<'a, G> for AttributeParseError {
                     format!("expected this to be of the form `{name} = \"...\"`"),
                 );
             }
-            AttributeParseErrorReason::ExpectedSpecificArgument { possibilities, strings } => {
+            AttributeParseErrorReason::ExpectedSpecificArgument {
+                possibilities,
+                strings,
+                list: false,
+            } => {
                 let quote = if strings { '"' } else { '`' };
                 match possibilities.as_slice() {
                     &[] => {}
@@ -641,6 +652,38 @@ impl<'a, G: EmissionGuarantee> Diagnostic<'a, G> for AttributeParseError {
                     }
                 }
             }
+            AttributeParseErrorReason::ExpectedSpecificArgument {
+                possibilities,
+                strings,
+                list: true,
+            } => {
+                let quote = if strings { '"' } else { '`' };
+                match possibilities.as_slice() {
+                    &[] => {}
+                    &[x] => {
+                        diag.span_label(
+                            self.span,
+                            format!(
+                                "this attribute is only valid with {quote}{x}{quote} as an argument"
+                            ),
+                        );
+                    }
+                    [first, second] => {
+                        diag.span_label(self.span, format!("this attribute is only valid with either {quote}{first}{quote} or {quote}{second}{quote} as an argument"));
+                    }
+                    [first @ .., second_to_last, last] => {
+                        let mut res = String::new();
+                        for i in first {
+                            res.push_str(&format!("{quote}{i}{quote}, "));
+                        }
+                        res.push_str(&format!(
+                            "{quote}{second_to_last}{quote} or {quote}{last}{quote}"
+                        ));
+
+                        diag.span_label(self.span, format!("this attribute is only valid with one of the following arguments: {res}"));
+                    }
+                }
+            }
         }
 
         let suggestions = self.template.suggestions(false, &name);

compiler/rustc_borrowck/src/type_check/constraint_conversion.rs

@@ -1,3 +1,4 @@
+use rustc_data_structures::fx::FxHashSet;
 use rustc_hir::def_id::LocalDefId;
 use rustc_infer::infer::canonical::QueryRegionConstraints;
 use rustc_infer::infer::outlives::env::RegionBoundPairs;
@@ -7,7 +8,7 @@ use rustc_infer::infer::{InferCtxt, SubregionOrigin};
 use rustc_infer::traits::query::type_op::DeeplyNormalize;
 use rustc_middle::bug;
 use rustc_middle::ty::{
-    self, GenericArgKind, Ty, TyCtxt, TypeFoldable, TypeVisitableExt, fold_regions,
+    self, GenericArgKind, Ty, TyCtxt, TypeFoldable, TypeVisitableExt, elaborate, fold_regions,
 };
 use rustc_span::Span;
 use rustc_trait_selection::traits::query::type_op::{TypeOp, TypeOpOutput};
@@ -70,10 +71,12 @@ impl<'a, 'tcx> ConstraintConversion<'a, 'tcx> {
 
     #[instrument(skip(self), level = "debug")]
     pub(super) fn convert_all(&mut self, query_constraints: &QueryRegionConstraints<'tcx>) {
-        let QueryRegionConstraints { outlives } = query_constraints;
+        let QueryRegionConstraints { outlives, assumptions } = query_constraints;
+        let assumptions =
+            elaborate::elaborate_outlives_assumptions(self.infcx.tcx, assumptions.iter().copied());
 
         for &(predicate, constraint_category) in outlives {
-            self.convert(predicate, constraint_category);
+            self.convert(predicate, constraint_category, &assumptions);
         }
     }
 
@@ -112,15 +115,20 @@ impl<'a, 'tcx> ConstraintConversion<'a, 'tcx> {
 
             self.category = outlives_requirement.category;
             self.span = outlives_requirement.blame_span;
-            self.convert(ty::OutlivesPredicate(subject, outlived_region), self.category);
+            self.convert(
+                ty::OutlivesPredicate(subject, outlived_region),
+                self.category,
+                &Default::default(),
+            );
         }
         (self.category, self.span, self.from_closure) = backup;
     }
 
     fn convert(
         &mut self,
-        predicate: ty::OutlivesPredicate<'tcx, ty::GenericArg<'tcx>>,
+        predicate: ty::ArgOutlivesPredicate<'tcx>,
         constraint_category: ConstraintCategory<'tcx>,
+        higher_ranked_assumptions: &FxHashSet<ty::ArgOutlivesPredicate<'tcx>>,
     ) {
         let tcx = self.infcx.tcx;
         debug!("generate: constraints at: {:#?}", self.locations);
@@ -150,7 +158,15 @@ impl<'a, 'tcx> ConstraintConversion<'a, 'tcx> {
             }
 
             let mut next_outlives_predicates = vec![];
-            for (ty::OutlivesPredicate(k1, r2), constraint_category) in outlives_predicates {
+            for (pred, constraint_category) in outlives_predicates {
+                // Constraint is implied by a coroutine's well-formedness.
+                if self.infcx.tcx.sess.opts.unstable_opts.higher_ranked_assumptions
+                    && higher_ranked_assumptions.contains(&pred)
+                {
+                    continue;
+                }
+
+                let ty::OutlivesPredicate(k1, r2) = pred;
                 match k1.kind() {
                     GenericArgKind::Lifetime(r1) => {
                         let r1_vid = self.to_region_vid(r1);
@@ -266,14 +282,15 @@ impl<'a, 'tcx> ConstraintConversion<'a, 'tcx> {
         &self,
         ty: Ty<'tcx>,
         next_outlives_predicates: &mut Vec<(
-            ty::OutlivesPredicate<'tcx, ty::GenericArg<'tcx>>,
+            ty::ArgOutlivesPredicate<'tcx>,
             ConstraintCategory<'tcx>,
         )>,
     ) -> Ty<'tcx> {
         match self.param_env.and(DeeplyNormalize { value: ty }).fully_perform(self.infcx, self.span)
         {
             Ok(TypeOpOutput { output: ty, constraints, .. }) => {
-                if let Some(QueryRegionConstraints { outlives }) = constraints {
+                // FIXME(higher_ranked_auto): What should we do with the assumptions here?
+                if let Some(QueryRegionConstraints { outlives, assumptions: _ }) = constraints {
                     next_outlives_predicates.extend(outlives.iter().copied());
                 }
                 ty

compiler/rustc_borrowck/src/type_check/mod.rs

@@ -131,6 +131,11 @@ pub(crate) fn type_check<'tcx>(
         pre_obligations.is_empty(),
         "there should be no incoming region obligations = {pre_obligations:#?}",
     );
+    let pre_assumptions = infcx.take_registered_region_assumptions();
+    assert!(
+        pre_assumptions.is_empty(),
+        "there should be no incoming region assumptions = {pre_assumptions:#?}",
+    );
 
     debug!(?normalized_inputs_and_output);