Rollup of 19 pull requests

Cargo.lock

@@ -4812,6 +4812,7 @@ dependencies = [
  "serde_json",
  "sha2",
  "smallvec",
+ "stringdex",
  "tempfile",
  "threadpool",
  "tracing",
@@ -5225,6 +5226,15 @@ dependencies = [
  "quote",
 ]
 
+[[package]]
+name = "stringdex"
+version = "0.0.1-alpha4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2841fd43df5b1ff1b042e167068a1fe9b163dc93041eae56ab2296859013a9a0"
+dependencies = [
+ "stacker",
+]
+
 [[package]]
 name = "strsim"
 version = "0.11.1"

compiler/rustc_attr_parsing/src/attributes/inline.rs

@@ -62,8 +62,8 @@ impl<S: Stage> SingleAttributeParser<S> for InlineParser {
                 }
             }
             ArgParser::NameValue(_) => {
-                let suggestions =
-                    <Self as SingleAttributeParser<S>>::TEMPLATE.suggestions(false, "inline");
+                let suggestions = <Self as SingleAttributeParser<S>>::TEMPLATE
+                    .suggestions(cx.attr_style, "inline");
                 let span = cx.attr_span;
                 cx.emit_lint(AttributeLintKind::IllFormedAttributeInput { suggestions }, span);
                 return None;

compiler/rustc_attr_parsing/src/attributes/macro_attrs.rs

@@ -107,7 +107,7 @@ impl<S: Stage> AttributeParser<S> for MacroUseParser {
                     }
                 }
                 ArgParser::NameValue(_) => {
-                    let suggestions = MACRO_USE_TEMPLATE.suggestions(false, sym::macro_use);
+                    let suggestions = MACRO_USE_TEMPLATE.suggestions(cx.attr_style, sym::macro_use);
                     cx.emit_err(session_diagnostics::IllFormedAttributeInputLint {
                         num_suggestions: suggestions.len(),
                         suggestions: DiagArgValue::StrListSepByAnd(

compiler/rustc_attr_parsing/src/attributes/must_use.rs

@@ -35,8 +35,8 @@ impl<S: Stage> SingleAttributeParser<S> for MustUseParser {
                     Some(value_str)
                 }
                 ArgParser::List(_) => {
-                    let suggestions =
-                        <Self as SingleAttributeParser<S>>::TEMPLATE.suggestions(false, "must_use");
+                    let suggestions = <Self as SingleAttributeParser<S>>::TEMPLATE
+                        .suggestions(cx.attr_style, "must_use");
                     cx.emit_err(session_diagnostics::IllFormedAttributeInputLint {
                         num_suggestions: suggestions.len(),
                         suggestions: DiagArgValue::StrListSepByAnd(

compiler/rustc_attr_parsing/src/attributes/test_attrs.rs

@@ -29,7 +29,7 @@ impl<S: Stage> SingleAttributeParser<S> for IgnoreParser {
                 ArgParser::NameValue(name_value) => {
                     let Some(str_value) = name_value.value_as_str() else {
                         let suggestions = <Self as SingleAttributeParser<S>>::TEMPLATE
-                            .suggestions(false, "ignore");
+                            .suggestions(cx.attr_style, "ignore");
                         let span = cx.attr_span;
                         cx.emit_lint(
                             AttributeLintKind::IllFormedAttributeInput { suggestions },
@@ -40,8 +40,8 @@ impl<S: Stage> SingleAttributeParser<S> for IgnoreParser {
                     Some(str_value)
                 }
                 ArgParser::List(_) => {
-                    let suggestions =
-                        <Self as SingleAttributeParser<S>>::TEMPLATE.suggestions(false, "ignore");
+                    let suggestions = <Self as SingleAttributeParser<S>>::TEMPLATE
+                        .suggestions(cx.attr_style, "ignore");
                     let span = cx.attr_span;
                     cx.emit_lint(AttributeLintKind::IllFormedAttributeInput { suggestions }, span);
                     return None;

compiler/rustc_attr_parsing/src/context.rs

@@ -5,7 +5,7 @@ use std::sync::LazyLock;
 
 use itertools::Itertools;
 use private::Sealed;
-use rustc_ast::{self as ast, LitKind, MetaItemLit, NodeId};
+use rustc_ast::{self as ast, AttrStyle, LitKind, MetaItemLit, NodeId};
 use rustc_errors::{DiagCtxtHandle, Diagnostic};
 use rustc_feature::{AttributeTemplate, Features};
 use rustc_hir::attrs::AttributeKind;
@@ -315,6 +315,7 @@ pub struct AcceptContext<'f, 'sess, S: Stage> {
     /// The span of the attribute currently being parsed
     pub(crate) attr_span: Span,
 
+    pub(crate) attr_style: AttrStyle,
     /// The expected structure of the attribute.
     ///
     /// Used in reporting errors to give a hint to users what the attribute *should* look like.
@@ -396,6 +397,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
                     i.kind.is_bytestr().then(|| self.sess().source_map().start_point(i.span))
                 }),
             },
+            attr_style: self.attr_style,
         })
     }
 
@@ -406,6 +408,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
             template: self.template.clone(),
             attribute: self.attr_path.clone(),
             reason: AttributeParseErrorReason::ExpectedIntegerLiteral,
+            attr_style: self.attr_style,
         })
     }
 
@@ -416,6 +419,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
             template: self.template.clone(),
             attribute: self.attr_path.clone(),
             reason: AttributeParseErrorReason::ExpectedList,
+            attr_style: self.attr_style,
         })
     }
 
@@ -426,6 +430,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
             template: self.template.clone(),
             attribute: self.attr_path.clone(),
             reason: AttributeParseErrorReason::ExpectedNoArgs,
+            attr_style: self.attr_style,
         })
     }
 
@@ -437,6 +442,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
             template: self.template.clone(),
             attribute: self.attr_path.clone(),
             reason: AttributeParseErrorReason::ExpectedIdentifier,
+            attr_style: self.attr_style,
         })
     }
 
@@ -449,6 +455,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
             template: self.template.clone(),
             attribute: self.attr_path.clone(),
             reason: AttributeParseErrorReason::ExpectedNameValue(name),
+            attr_style: self.attr_style,
         })
     }
 
@@ -460,6 +467,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
             template: self.template.clone(),
             attribute: self.attr_path.clone(),
             reason: AttributeParseErrorReason::DuplicateKey(key),
+            attr_style: self.attr_style,
         })
     }
 
@@ -472,6 +480,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
             template: self.template.clone(),
             attribute: self.attr_path.clone(),
             reason: AttributeParseErrorReason::UnexpectedLiteral,
+            attr_style: self.attr_style,
         })
     }
 
@@ -482,6 +491,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
             template: self.template.clone(),
             attribute: self.attr_path.clone(),
             reason: AttributeParseErrorReason::ExpectedSingleArgument,
+            attr_style: self.attr_style,
         })
     }
 
@@ -492,6 +502,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
             template: self.template.clone(),
             attribute: self.attr_path.clone(),
             reason: AttributeParseErrorReason::ExpectedAtLeastOneArgument,
+            attr_style: self.attr_style,
         })
     }
 
@@ -510,6 +521,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
                 strings: false,
                 list: false,
             },
+            attr_style: self.attr_style,
         })
     }
 
@@ -528,6 +540,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
                 strings: false,
                 list: true,
             },
+            attr_style: self.attr_style,
         })
     }
 
@@ -546,6 +559,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
                 strings: true,
                 list: false,
             },
+            attr_style: self.attr_style,
         })
     }
 
@@ -804,6 +818,7 @@ impl<'sess> AttributeParser<'sess, Early> {
                 },
             },
             attr_span: attr.span,
+            attr_style: attr.style,
             template,
             attr_path: path.get_attribute_path(),
         };
@@ -914,6 +929,7 @@ impl<'sess, S: Stage> AttributeParser<'sess, S> {
                                     emit_lint: &mut emit_lint,
                                 },
                                 attr_span: lower_span(attr.span),
+                                attr_style: attr.style,
                                 template: &accept.template,
                                 attr_path: path.get_attribute_path(),
                             };

compiler/rustc_attr_parsing/src/session_diagnostics.rs

@@ -1,6 +1,6 @@
 use std::num::IntErrorKind;
 
-use rustc_ast as ast;
+use rustc_ast::{self as ast, AttrStyle};
 use rustc_errors::codes::*;
 use rustc_errors::{
     Applicability, Diag, DiagArgValue, DiagCtxtHandle, Diagnostic, EmissionGuarantee, Level,
@@ -579,6 +579,7 @@ pub(crate) enum AttributeParseErrorReason {
 pub(crate) struct AttributeParseError {
     pub(crate) span: Span,
     pub(crate) attr_span: Span,
+    pub(crate) attr_style: AttrStyle,
     pub(crate) template: AttributeTemplate,
     pub(crate) attribute: AttrPath,
     pub(crate) reason: AttributeParseErrorReason,
@@ -717,7 +718,8 @@ impl<'a, G: EmissionGuarantee> Diagnostic<'a, G> for AttributeParseError {
         if let Some(link) = self.template.docs {
             diag.note(format!("for more information, visit <{link}>"));
         }
-        let suggestions = self.template.suggestions(false, &name);
+        let suggestions = self.template.suggestions(self.attr_style, &name);
+
         diag.span_suggestions(
             self.attr_span,
             if suggestions.len() == 1 {

compiler/rustc_borrowck/messages.ftl

@@ -90,7 +90,7 @@ borrowck_lifetime_constraints_error =
     lifetime may not live long enough
 
 borrowck_limitations_implies_static =
-    due to current limitations in the borrow checker, this implies a `'static` lifetime
+    due to a current limitation of the type system, this implies a `'static` lifetime
 
 borrowck_move_closure_suggestion =
     consider adding 'move' keyword before the nested closure

compiler/rustc_borrowck/src/diagnostics/mod.rs

@@ -6,7 +6,9 @@ use rustc_abi::{FieldIdx, VariantIdx};
 use rustc_data_structures::fx::FxIndexMap;
 use rustc_errors::{Applicability, Diag, EmissionGuarantee, MultiSpan, listify};
 use rustc_hir::def::{CtorKind, Namespace};
-use rustc_hir::{self as hir, CoroutineKind, LangItem};
+use rustc_hir::{
+    self as hir, CoroutineKind, GenericBound, LangItem, WhereBoundPredicate, WherePredicateKind,
+};
 use rustc_index::{IndexSlice, IndexVec};
 use rustc_infer::infer::{BoundRegionConversionTime, NllRegionVariableOrigin};
 use rustc_infer::traits::SelectionError;
@@ -658,25 +660,66 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {
 
     /// Add a note to region errors and borrow explanations when higher-ranked regions in predicates
     /// implicitly introduce an "outlives `'static`" constraint.
+    ///
+    /// This is very similar to `fn suggest_static_lifetime_for_gat_from_hrtb` which handles this
+    /// note for failed type tests instead of outlives errors.
     fn add_placeholder_from_predicate_note<G: EmissionGuarantee>(
         &self,
-        err: &mut Diag<'_, G>,
+        diag: &mut Diag<'_, G>,
         path: &[OutlivesConstraint<'tcx>],
     ) {
-        let predicate_span = path.iter().find_map(|constraint| {
+        let tcx = self.infcx.tcx;
+        let Some((gat_hir_id, generics)) = path.iter().find_map(|constraint| {
             let outlived = constraint.sub;
             if let Some(origin) = self.regioncx.definitions.get(outlived)
-                && let NllRegionVariableOrigin::Placeholder(_) = origin.origin
-                && let ConstraintCategory::Predicate(span) = constraint.category
+                && let NllRegionVariableOrigin::Placeholder(placeholder) = origin.origin
+                && let Some(id) = placeholder.bound.kind.get_id()
+                && let Some(placeholder_id) = id.as_local()
+                && let gat_hir_id = tcx.local_def_id_to_hir_id(placeholder_id)
+                && let Some(generics_impl) =
+                    tcx.parent_hir_node(tcx.parent_hir_id(gat_hir_id)).generics()
             {
-                Some(span)
+                Some((gat_hir_id, generics_impl))
             } else {
                 None
             }
-        });
+        }) else {
+            return;
+        };
 
-        if let Some(span) = predicate_span {
-            err.span_note(span, "due to current limitations in the borrow checker, this implies a `'static` lifetime");
+        // Look for the where-bound which introduces the placeholder.
+        // As we're using the HIR, we need to handle both `for<'a> T: Trait<'a>`
+        // and `T: for<'a> Trait`<'a>.
+        for pred in generics.predicates {
+            let WherePredicateKind::BoundPredicate(WhereBoundPredicate {
+                bound_generic_params,
+                bounds,
+                ..
+            }) = pred.kind
+            else {
+                continue;
+            };
+            if bound_generic_params
+                .iter()
+                .rfind(|bgp| tcx.local_def_id_to_hir_id(bgp.def_id) == gat_hir_id)
+                .is_some()
+            {
+                diag.span_note(pred.span, fluent::borrowck_limitations_implies_static);
+                return;
+            }
+            for bound in bounds.iter() {
+                if let GenericBound::Trait(bound) = bound {
+                    if bound
+                        .bound_generic_params
+                        .iter()
+                        .rfind(|bgp| tcx.local_def_id_to_hir_id(bgp.def_id) == gat_hir_id)
+                        .is_some()
+                    {
+                        diag.span_note(bound.span, fluent::borrowck_limitations_implies_static);
+                        return;
+                    }
+                }
+            }
         }
     }