Auto merge of rust-lang#137982 - matthiaskrgr:rollup-12jvilg, r=matthiaskrgr

Rollup of 12 pull requests

Successful merges:

 - rust-lang#136975 (Look for `python3` first on MacOS, not `py`)
 - rust-lang#137240 (Slightly reformat `std::fs::remove_dir_all` error docs)
 - rust-lang#137303 (Remove `MaybeForgetReturn` suggestion)
 - rust-lang#137463 ([illumos] attempt to use posix_spawn to spawn processes)
 - rust-lang#137722 (`librustdoc`: 2024 edition! 🎊)
 - rust-lang#137758 (fix usage of ty decl macro fragments in attributes)
 - rust-lang#137772 (Fix char count in `Display` for `ByteStr`)
 - rust-lang#137805 (adjust Layout debug printing to match the internal field name)
 - rust-lang#137808 (Do not require that unsafe fields lack drop glue)
 - rust-lang#137913 (Allow struct field default values to reference struct's generics)
 - rust-lang#137963 (Add ``dyn`` keyword to `E0373` examples)
 - rust-lang#137975 (Remove unused `PpMode::needs_hir`)

r? `@ghost`
`@rustbot` modify labels: rollup

Author: bors

compiler/rustc_abi/src/lib.rs

@@ -1812,7 +1812,7 @@ where
         f.debug_struct("Layout")
             .field("size", size)
             .field("align", align)
-            .field("abi", backend_repr)
+            .field("backend_repr", backend_repr)
             .field("fields", fields)
             .field("largest_niche", largest_niche)
             .field("uninhabited", uninhabited)

compiler/rustc_attr_parsing/src/parser.rs

@@ -473,6 +473,15 @@ impl<'a> MetaItemListParserContext<'a> {
         {
             self.inside_delimiters.next();
             return Some(MetaItemOrLitParser::Lit(lit));
+        } else if let Some(TokenTree::Delimited(.., Delimiter::Invisible(_), inner_tokens)) =
+            self.inside_delimiters.peek()
+        {
+            self.inside_delimiters.next();
+            return MetaItemListParserContext {
+                inside_delimiters: inner_tokens.iter().peekable(),
+                dcx: self.dcx,
+            }
+            .next();
         }
 
         // or a path.

compiler/rustc_data_structures/src/captures.rs

@@ -48,7 +48,6 @@ pub use rustc_index::static_assert_size;
 pub mod aligned;
 pub mod base_n;
 pub mod binary_search_util;
-pub mod captures;
 pub mod fingerprint;
 pub mod flat_map_in_place;
 pub mod flock;

compiler/rustc_data_structures/src/lib.rs

@@ -3,7 +3,7 @@ A captured variable in a closure may not live long enough.
 Erroneous code example:
 
 ```compile_fail,E0373
-fn foo() -> Box<Fn(u32) -> u32> {
+fn foo() -> Box<dyn Fn(u32) -> u32> {
     let x = 0u32;
     Box::new(|y| x + y)
 }
@@ -42,7 +42,7 @@ This approach moves (or copies, where possible) data into the closure, rather
 than taking references to it. For example:
 
 ```
-fn foo() -> Box<Fn(u32) -> u32> {
+fn foo() -> Box<dyn Fn(u32) -> u32> {
     let x = 0u32;
     Box::new(move |y| x + y)
 }

compiler/rustc_error_codes/src/error_codes/E0373.md

@@ -626,7 +626,6 @@ pub enum StashKey {
     MaybeFruTypo,
     CallAssocMethod,
     AssociatedTypeSuggestion,
-    MaybeForgetReturn,
     /// Query cycle detected, stashing in favor of a better error.
     Cycle,
     UndeterminedMacroResolution,

compiler/rustc_errors/src/lib.rs

@@ -278,13 +278,6 @@ hir_analysis_invalid_union_field =
 hir_analysis_invalid_union_field_sugg =
     wrap the field type in `ManuallyDrop<...>`
 
-hir_analysis_invalid_unsafe_field =
-    field must implement `Copy` or be wrapped in `ManuallyDrop<...>` to be unsafe
-    .note = unsafe fields must not have drop side-effects, which is currently enforced via either `Copy` or `ManuallyDrop<...>`
-
-hir_analysis_invalid_unsafe_field_sugg =
-    wrap the field type in `ManuallyDrop<...>`
-
 hir_analysis_late_bound_const_in_apit = `impl Trait` can only mention const parameters from an fn or impl
     .label = const parameter declared here
 

compiler/rustc_hir_analysis/messages.ftl

@@ -70,7 +70,6 @@ fn check_struct(tcx: TyCtxt<'_>, def_id: LocalDefId) {
 
     check_transparent(tcx, def);
     check_packed(tcx, span, def);
-    check_unsafe_fields(tcx, def_id);
 }
 
 fn check_union(tcx: TyCtxt<'_>, def_id: LocalDefId) {
@@ -144,36 +143,6 @@ fn check_union_fields(tcx: TyCtxt<'_>, span: Span, item_def_id: LocalDefId) -> b
     true
 }
 
-/// Check that the unsafe fields do not need dropping.
-fn check_unsafe_fields(tcx: TyCtxt<'_>, item_def_id: LocalDefId) {
-    let span = tcx.def_span(item_def_id);
-    let def = tcx.adt_def(item_def_id);
-
-    let typing_env = ty::TypingEnv::non_body_analysis(tcx, item_def_id);
-    let args = ty::GenericArgs::identity_for_item(tcx, item_def_id);
-
-    for field in def.all_fields() {
-        if !field.safety.is_unsafe() {
-            continue;
-        }
-
-        if !allowed_union_or_unsafe_field(tcx, field.ty(tcx, args), typing_env, span) {
-            let hir::Node::Field(field) = tcx.hir_node_by_def_id(field.did.expect_local()) else {
-                unreachable!("field has to correspond to hir field")
-            };
-            let ty_span = field.ty.span;
-            tcx.dcx().emit_err(errors::InvalidUnsafeField {
-                field_span: field.span,
-                sugg: errors::InvalidUnsafeFieldSuggestion {
-                    lo: ty_span.shrink_to_lo(),
-                    hi: ty_span.shrink_to_hi(),
-                },
-                note: (),
-            });
-        }
-    }
-}
-
 /// Check that a `static` is inhabited.
 fn check_static_inhabited(tcx: TyCtxt<'_>, def_id: LocalDefId) {
     // Make sure statics are inhabited.
@@ -1517,7 +1486,6 @@ fn check_enum(tcx: TyCtxt<'_>, def_id: LocalDefId) {
 
     detect_discriminant_duplicate(tcx, def);
     check_transparent(tcx, def);
-    check_unsafe_fields(tcx, def_id);
 }
 
 /// Part of enum check. Given the discriminants of an enum, errors if two or more discriminants are equal

compiler/rustc_hir_analysis/src/check/check.rs

@@ -187,6 +187,8 @@ pub(super) fn generics_of(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::Generics {
                         Some(parent_did)
                     }
                     Node::TyPat(_) => Some(parent_did),
+                    // Field default values inherit the ADT's generics.
+                    Node::Field(_) => Some(parent_did),
                     _ => None,
                 }
             }

compiler/rustc_hir_analysis/src/collect/generics_of.rs

@@ -710,17 +710,6 @@ pub(crate) struct InvalidUnionField {
     pub note: (),
 }
 
-#[derive(Diagnostic)]
-#[diag(hir_analysis_invalid_unsafe_field, code = E0740)]
-pub(crate) struct InvalidUnsafeField {
-    #[primary_span]
-    pub field_span: Span,
-    #[subdiagnostic]
-    pub sugg: InvalidUnsafeFieldSuggestion,
-    #[note]
-    pub note: (),
-}
-
 #[derive(Diagnostic)]
 #[diag(hir_analysis_return_type_notation_on_non_rpitit)]
 pub(crate) struct ReturnTypeNotationOnNonRpitit<'tcx> {
@@ -742,18 +731,6 @@ pub(crate) struct InvalidUnionFieldSuggestion {
     pub hi: Span,
 }
 
-#[derive(Subdiagnostic)]
-#[multipart_suggestion(
-    hir_analysis_invalid_unsafe_field_sugg,
-    applicability = "machine-applicable"
-)]
-pub(crate) struct InvalidUnsafeFieldSuggestion {
-    #[suggestion_part(code = "std::mem::ManuallyDrop<")]
-    pub lo: Span,
-    #[suggestion_part(code = ">")]
-    pub hi: Span,
-}
-
 #[derive(Diagnostic)]
 #[diag(hir_analysis_return_type_notation_equality_bound)]
 pub(crate) struct ReturnTypeNotationEqualityBound {

compiler/rustc_hir_analysis/src/errors.rs

@@ -669,12 +669,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
         if !errors.is_empty() {
             self.adjust_fulfillment_errors_for_expr_obligation(&mut errors);
-            let errors_causecode = errors
-                .iter()
-                .map(|e| (e.obligation.cause.span, e.root_obligation.cause.code().clone()))
-                .collect::<Vec<_>>();
             self.err_ctxt().report_fulfillment_errors(errors);
-            self.collect_unused_stmts_for_coerce_return_ty(errors_causecode);
         }
     }
 

compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs

@@ -3,9 +3,7 @@ use std::{fmt, iter, mem};
 use itertools::Itertools;
 use rustc_data_structures::fx::FxIndexSet;
 use rustc_errors::codes::*;
-use rustc_errors::{
-    Applicability, Diag, ErrorGuaranteed, MultiSpan, StashKey, a_or_an, listify, pluralize,
-};
+use rustc_errors::{Applicability, Diag, ErrorGuaranteed, MultiSpan, a_or_an, listify, pluralize};
 use rustc_hir::def::{CtorOf, DefKind, Res};
 use rustc_hir::def_id::DefId;
 use rustc_hir::intravisit::Visitor;
@@ -2193,62 +2191,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         }
     }
 
-    pub(super) fn collect_unused_stmts_for_coerce_return_ty(
-        &self,
-        errors_causecode: Vec<(Span, ObligationCauseCode<'tcx>)>,
-    ) {
-        for (span, code) in errors_causecode {
-            self.dcx().try_steal_modify_and_emit_err(span, StashKey::MaybeForgetReturn, |err| {
-                if let Some(fn_sig) = self.body_fn_sig()
-                    && let ObligationCauseCode::WhereClauseInExpr(_, _, binding_hir_id, ..) = code
-                    && !fn_sig.output().is_unit()
-                {
-                    let mut block_num = 0;
-                    let mut found_semi = false;
-                    for (hir_id, node) in self.tcx.hir_parent_iter(binding_hir_id) {
-                        // Don't proceed into parent bodies
-                        if hir_id.owner != binding_hir_id.owner {
-                            break;
-                        }
-                        match node {
-                            hir::Node::Stmt(stmt) => {
-                                if let hir::StmtKind::Semi(expr) = stmt.kind {
-                                    let expr_ty = self.typeck_results.borrow().expr_ty(expr);
-                                    let return_ty = fn_sig.output();
-                                    if !matches!(expr.kind, hir::ExprKind::Ret(..))
-                                        && self.may_coerce(expr_ty, return_ty)
-                                    {
-                                        found_semi = true;
-                                    }
-                                }
-                            }
-                            hir::Node::Block(_block) => {
-                                if found_semi {
-                                    block_num += 1;
-                                }
-                            }
-                            hir::Node::Item(item) => {
-                                if let hir::ItemKind::Fn { .. } = item.kind {
-                                    break;
-                                }
-                            }
-                            _ => {}
-                        }
-                    }
-                    if block_num > 1 && found_semi {
-                        err.span_suggestion_verbose(
-                            // use the span of the *whole* expr
-                            self.tcx.hir().span(binding_hir_id).shrink_to_lo(),
-                            "you might have meant to return this to infer its type parameters",
-                            "return ",
-                            Applicability::MaybeIncorrect,
-                        );
-                    }
-                }
-            });
-        }
-    }
-
     /// Given a vector of fulfillment errors, try to adjust the spans of the
     /// errors to more accurately point at the cause of the failure.
     ///

compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs

@@ -78,6 +78,7 @@ struct IsNeverPattern;
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
 enum AnonConstKind {
     EnumDiscriminant,
+    FieldDefaultValue,
     InlineConst,
     ConstArg(IsRepeatExpr),
 }
@@ -1406,7 +1407,7 @@ impl<'ra: 'ast, 'ast, 'tcx> Visitor<'ast> for LateResolutionVisitor<'_, 'ast, 'r
         visit_opt!(self, visit_ident, ident);
         try_visit!(self.visit_ty(ty));
         if let Some(v) = &default {
-            self.resolve_anon_const(v, AnonConstKind::ConstArg(IsRepeatExpr::No));
+            self.resolve_anon_const(v, AnonConstKind::FieldDefaultValue);
         }
     }
 }
@@ -4658,6 +4659,7 @@ impl<'a, 'ast, 'ra: 'ast, 'tcx> LateResolutionVisitor<'a, 'ast, 'ra, 'tcx> {
             AnonConstKind::EnumDiscriminant => {
                 ConstantHasGenerics::No(NoConstantGenericsReason::IsEnumDiscriminant)
             }
+            AnonConstKind::FieldDefaultValue => ConstantHasGenerics::Yes,
             AnonConstKind::InlineConst => ConstantHasGenerics::Yes,
             AnonConstKind::ConstArg(_) => {
                 if self.r.tcx.features().generic_const_exprs() || is_trivial_const_arg {

compiler/rustc_resolve/src/late.rs

@@ -2887,14 +2887,6 @@ impl PpMode {
             | StableMir => true,
         }
     }
-    pub fn needs_hir(&self) -> bool {
-        use PpMode::*;
-        match *self {
-            Source(_) | AstTree | AstTreeExpanded => false,
-
-            Hir(_) | HirTree | ThirTree | ThirFlat | Mir | MirCFG | StableMir => true,
-        }
-    }
 
     pub fn needs_analysis(&self) -> bool {
         use PpMode::*;

compiler/rustc_session/src/config.rs

@@ -1,8 +1,6 @@
 use std::ops::ControlFlow;
 
-use rustc_errors::{
-    Applicability, Diag, E0283, E0284, E0790, MultiSpan, StashKey, struct_span_code_err,
-};
+use rustc_errors::{Applicability, Diag, E0283, E0284, E0790, MultiSpan, struct_span_code_err};
 use rustc_hir as hir;
 use rustc_hir::LangItem;
 use rustc_hir::def::{DefKind, Res};
@@ -197,7 +195,7 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
                 // be ignoring the fact that we don't KNOW the type works
                 // out. Though even that would probably be harmless, given that
                 // we're only talking about builtin traits, which are known to be
-                // inhabited. We used to check for `self.tcx.sess.has_errors()` to
+                // inhabited. We used to check for `self.tainted_by_errors()` to
                 // avoid inundating the user with unnecessary errors, but we now
                 // check upstream for type errors and don't add the obligations to
                 // begin with in those cases.
@@ -211,7 +209,7 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
                                 TypeAnnotationNeeded::E0282,
                                 false,
                             );
-                            return err.stash(span, StashKey::MaybeForgetReturn).unwrap();
+                            return err.emit();
                         }
                         Some(e) => return e,
                     }

compiler/rustc_trait_selection/src/error_reporting/traits/ambiguity.rs

@@ -151,9 +151,9 @@ dependencies = [
 
 [[package]]
 name = "libc"
-version = "0.2.169"
+version = "0.2.170"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b5aba8db14291edd000dfcc4d620c7ebfb122c613afb886ca8803fa4e128a20a"
+checksum = "875b3680cb2f8f71bdcf9a30f38d48282f5d3c95cbf9b3fa57269bb5d5c06828"
 dependencies = [
  "rustc-std-workspace-core",
 ]

library/Cargo.lock

@@ -151,7 +151,9 @@ impl fmt::Display for ByteStr {
         };
         let nchars: usize = self
             .utf8_chunks()
-            .map(|chunk| chunk.valid().len() + if chunk.invalid().is_empty() { 0 } else { 1 })
+            .map(|chunk| {
+                chunk.valid().chars().count() + if chunk.invalid().is_empty() { 0 } else { 1 }
+            })
             .sum();
         let padding = f.width().unwrap_or(0).saturating_sub(nchars);
         let fill = f.fill();

library/core/src/bstr.rs

@@ -453,8 +453,8 @@ impl Copy for ! {}
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<T: ?Sized> Copy for &T {}
 
-/// Marker trait for the types that are allowed in union fields, unsafe fields,
-/// and unsafe binder types.
+/// Marker trait for the types that are allowed in union fields and unsafe
+/// binder types.
 ///
 /// Implemented for:
 /// * `&T`, `&mut T` for all `T`,

library/core/src/marker.rs

@@ -35,7 +35,7 @@ miniz_oxide = { version = "0.8.0", optional = true, default-features = false }
 addr2line = { version = "0.24.0", optional = true, default-features = false }
 
 [target.'cfg(not(all(windows, target_env = "msvc")))'.dependencies]
-libc = { version = "0.2.169", default-features = false, features = [
+libc = { version = "0.2.170", default-features = false, features = [
     'rustc-dep-of-std',
 ], public = true }
 

library/std/Cargo.toml

@@ -2857,9 +2857,11 @@ pub fn remove_dir<P: AsRef<Path>>(path: P) -> io::Result<()> {
 ///
 /// See [`fs::remove_file`] and [`fs::remove_dir`].
 ///
-/// `remove_dir_all` will fail if `remove_dir` or `remove_file` fail on any constituent paths, including the root `path`.
-/// As a result, the directory you are deleting must exist, meaning that this function is not idempotent.
-/// Additionally, `remove_dir_all` will also fail if the `path` is not a directory.
+/// [`remove_dir_all`] will fail if [`remove_dir`] or [`remove_file`] fail on *any* constituent
+/// paths, *including* the root `path`. Consequently,
+///
+/// - The directory you are deleting *must* exist, meaning that this function is *not idempotent*.
+/// - [`remove_dir_all`] will fail if the `path` is *not* a directory.
 ///
 /// Consider ignoring the error if validating the removal is not required for your use case.
 ///