Merge from rustc

Author: The Miri Cronjob Bot

Diff for: .github/workflows/ci.yml

@@ -46,7 +46,7 @@ jobs:
   # If you want to modify CI jobs, take a look at src/ci/github-actions/jobs.yml.
   calculate_matrix:
     name: Calculate job matrix
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     outputs:
       jobs: ${{ steps.jobs.outputs.jobs }}
       run_type: ${{ steps.jobs.outputs.run_type }}
@@ -243,7 +243,7 @@ jobs:
   # when a workflow is successful listening to webhooks only in our current bors implementation (homu).
   outcome:
     name: bors build finished
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     needs: [ calculate_matrix, job ]
     # !cancelled() executes the job regardless of whether the previous jobs passed or failed
     if: ${{ !cancelled() && contains(fromJSON('["auto", "try"]'), needs.calculate_matrix.outputs.run_type) }}

Diff for: .github/workflows/dependencies.yml

@@ -27,7 +27,7 @@ jobs:
   not-waiting-on-bors:
     if: github.repository_owner == 'rust-lang'
     name: skip if S-waiting-on-bors
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     steps:
       - env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
@@ -47,7 +47,7 @@ jobs:
     if: github.repository_owner == 'rust-lang'
     name: update dependencies
     needs: not-waiting-on-bors
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     steps:
       - name: checkout the source code
         uses: actions/checkout@v4
@@ -94,7 +94,7 @@ jobs:
     if: github.repository_owner == 'rust-lang'
     name: amend PR
     needs: update
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     permissions:
       contents: write
       pull-requests: write

Diff for: Cargo.lock

@@ -3722,6 +3722,7 @@ dependencies = [
  "rustc_fluent_macro",
  "rustc_hir",
  "rustc_index",
+ "rustc_lexer",
  "rustc_lint_defs",
  "rustc_macros",
  "rustc_serialize",

Diff for: compiler/rustc_ast/src/ast.rs

@@ -1322,11 +1322,15 @@ impl Expr {
     }
 
     pub fn precedence(&self) -> ExprPrecedence {
-        match self.kind {
-            ExprKind::Closure(..) => ExprPrecedence::Closure,
+        match &self.kind {
+            ExprKind::Closure(closure) => {
+                match closure.fn_decl.output {
+                    FnRetTy::Default(_) => ExprPrecedence::Jump,
+                    FnRetTy::Ty(_) => ExprPrecedence::Unambiguous,
+                }
+            }
 
             ExprKind::Break(..)
-            | ExprKind::Continue(..)
             | ExprKind::Ret(..)
             | ExprKind::Yield(..)
             | ExprKind::Yeet(..)
@@ -1360,6 +1364,7 @@ impl Expr {
             | ExprKind::Block(..)
             | ExprKind::Call(..)
             | ExprKind::ConstBlock(_)
+            | ExprKind::Continue(..)
             | ExprKind::Field(..)
             | ExprKind::ForLoop { .. }
             | ExprKind::FormatArgs(..)

Diff for: compiler/rustc_ast/src/util/parser.rs

@@ -231,8 +231,7 @@ impl AssocOp {
 
 #[derive(Clone, Copy, PartialEq, PartialOrd)]
 pub enum ExprPrecedence {
-    Closure,
-    // return, break, yield
+    // return, break, yield, closures
     Jump,
     // = += -= *= /= %= &= |= ^= <<= >>=
     Assign,

Diff for: compiler/rustc_borrowck/src/region_infer/mod.rs

@@ -795,7 +795,6 @@ impl<'tcx> RegionInferenceContext<'tcx> {
 
         // If the member region lives in a higher universe, we currently choose
         // the most conservative option by leaving it unchanged.
-
         if !self.constraint_sccs().annotation(scc).min_universe().is_root() {
             return;
         }
@@ -823,12 +822,14 @@ impl<'tcx> RegionInferenceContext<'tcx> {
         }
         debug!(?choice_regions, "after ub");
 
-        // At this point we can pick any member of `choice_regions`, but to avoid potential
-        // non-determinism we will pick the *unique minimum* choice.
+        // At this point we can pick any member of `choice_regions` and would like to choose
+        // it to be a small as possible. To avoid potential non-determinism we will pick the
+        // smallest such choice.
         //
         // Because universal regions are only partially ordered (i.e, not every two regions are
         // comparable), we will ignore any region that doesn't compare to all others when picking
         // the minimum choice.
+        //
         // For example, consider `choice_regions = ['static, 'a, 'b, 'c, 'd, 'e]`, where
         // `'static: 'a, 'static: 'b, 'a: 'c, 'b: 'c, 'c: 'd, 'c: 'e`.
         // `['d, 'e]` are ignored because they do not compare - the same goes for `['a, 'b]`.
@@ -853,6 +854,8 @@ impl<'tcx> RegionInferenceContext<'tcx> {
             return;
         };
 
+        // As we require `'scc: 'min_choice`, we have definitely already computed
+        // its `scc_values` at this point.
         let min_choice_scc = self.constraint_sccs.scc(min_choice);
         debug!(?min_choice, ?min_choice_scc);
         if self.scc_values.add_region(scc, min_choice_scc) {

Diff for: compiler/rustc_codegen_cranelift/src/driver/jit.rs

@@ -294,7 +294,7 @@ fn dep_symbol_lookup_fn(
     // search path.
     for &cnum in crate_info.used_crates.iter().rev() {
         let src = &crate_info.used_crate_source[&cnum];
-        match data[cnum.as_usize() - 1] {
+        match data[cnum] {
             Linkage::NotLinked | Linkage::IncludedFromDylib => {}
             Linkage::Static => {
                 let name = crate_info.crate_name[&cnum];

Diff for: compiler/rustc_codegen_llvm/src/llvm/ffi.rs

@@ -56,25 +56,6 @@ pub enum LLVMRustResult {
     Failure,
 }
 
-// Rust version of the C struct with the same name in rustc_llvm/llvm-wrapper/RustWrapper.cpp.
-#[repr(C)]
-pub struct LLVMRustCOFFShortExport {
-    pub name: *const c_char,
-    pub ordinal_present: bool,
-    /// value of `ordinal` only important when `ordinal_present` is true
-    pub ordinal: u16,
-}
-
-impl LLVMRustCOFFShortExport {
-    pub fn new(name: *const c_char, ordinal: Option<u16>) -> LLVMRustCOFFShortExport {
-        LLVMRustCOFFShortExport {
-            name,
-            ordinal_present: ordinal.is_some(),
-            ordinal: ordinal.unwrap_or(0),
-        }
-    }
-}
-
 /// Translation of LLVM's MachineTypes enum, defined in llvm\include\llvm\BinaryFormat\COFF.h.
 ///
 /// We include only architectures supported on Windows.
@@ -2347,15 +2328,6 @@ unsafe extern "C" {
     ) -> &'a mut RustArchiveMember<'a>;
     pub fn LLVMRustArchiveMemberFree<'a>(Member: &'a mut RustArchiveMember<'a>);
 
-    pub fn LLVMRustWriteImportLibrary(
-        ImportName: *const c_char,
-        Path: *const c_char,
-        Exports: *const LLVMRustCOFFShortExport,
-        NumExports: usize,
-        Machine: u16,
-        MinGW: bool,
-    ) -> LLVMRustResult;
-
     pub fn LLVMRustSetDataLayoutFromTargetMachine<'a>(M: &'a Module, TM: &'a TargetMachine);
 
     pub fn LLVMRustPositionBuilderAtStart<'a>(B: &Builder<'a>, BB: &'a BasicBlock);

Diff for: compiler/rustc_codegen_ssa/src/back/link.rs

@@ -15,7 +15,7 @@ use rustc_ast::CRATE_NODE_ID;
 use rustc_data_structures::fx::{FxIndexMap, FxIndexSet};
 use rustc_data_structures::memmap::Mmap;
 use rustc_data_structures::temp_dir::MaybeTempDir;
-use rustc_errors::{DiagCtxtHandle, FatalError};
+use rustc_errors::DiagCtxtHandle;
 use rustc_fs_util::{fix_windows_verbatim_for_gcc, try_canonicalize};
 use rustc_hir::def_id::{CrateNum, LOCAL_CRATE};
 use rustc_metadata::fs::{METADATA_FILENAME, copy_to_stdout, emit_wrapper_file};
@@ -234,8 +234,6 @@ pub fn each_linked_rlib(
     crate_type: Option<CrateType>,
     f: &mut dyn FnMut(CrateNum, &Path),
 ) -> Result<(), errors::LinkRlibError> {
-    let crates = info.used_crates.iter();
-
     let fmts = if let Some(crate_type) = crate_type {
         let Some(fmts) = info.dependency_formats.get(&crate_type) else {
             return Err(errors::LinkRlibError::MissingFormat);
@@ -261,8 +259,9 @@ pub fn each_linked_rlib(
         info.dependency_formats.first().unwrap().1
     };
 
-    for &cnum in crates {
-        match fmts.get(cnum.as_usize() - 1) {
+    let used_dep_crates = info.used_crates.iter();
+    for &cnum in used_dep_crates {
+        match fmts.get(cnum) {
             Some(&Linkage::NotLinked | &Linkage::Dynamic | &Linkage::IncludedFromDylib) => continue,
             Some(_) => {}
             None => return Err(errors::LinkRlibError::MissingFormat),
@@ -624,7 +623,7 @@ fn link_staticlib(
 
     let mut all_rust_dylibs = vec![];
     for &cnum in crates {
-        match fmts.get(cnum.as_usize() - 1) {
+        match fmts.get(cnum) {
             Some(&Linkage::Dynamic) => {}
             _ => continue,
         }
@@ -1039,22 +1038,22 @@ fn link_natively(
         Err(e) => {
             let linker_not_found = e.kind() == io::ErrorKind::NotFound;
 
-            if linker_not_found {
-                sess.dcx().emit_err(errors::LinkerNotFound { linker_path, error: e });
+            let err = if linker_not_found {
+                sess.dcx().emit_err(errors::LinkerNotFound { linker_path, error: e })
             } else {
                 sess.dcx().emit_err(errors::UnableToExeLinker {
                     linker_path,
                     error: e,
                     command_formatted: format!("{cmd:?}"),
-                });
-            }
+                })
+            };
 
             if sess.target.is_like_msvc && linker_not_found {
                 sess.dcx().emit_note(errors::MsvcMissingLinker);
                 sess.dcx().emit_note(errors::CheckInstalledVisualStudio);
                 sess.dcx().emit_note(errors::InsufficientVSCodeProduct);
             }
-            FatalError.raise();
+            err.raise_fatal();
         }
     }
 
@@ -2361,8 +2360,8 @@ fn linker_with_args(
         .crate_info
         .native_libraries
         .iter()
-        .filter_map(|(cnum, libraries)| {
-            (dependency_linkage[cnum.as_usize() - 1] != Linkage::Static).then_some(libraries)
+        .filter_map(|(&cnum, libraries)| {
+            (dependency_linkage[cnum] != Linkage::Static).then_some(libraries)
         })
         .flatten()
         .collect::<Vec<_>>();
@@ -2754,7 +2753,7 @@ fn add_upstream_rust_crates(
         // (e.g. `libstd` when `-C prefer-dynamic` is used).
         // FIXME: `dependency_formats` can report `profiler_builtins` as `NotLinked` for some
         // reason, it shouldn't do that because `profiler_builtins` should indeed be linked.
-        let linkage = data[cnum.as_usize() - 1];
+        let linkage = data[cnum];
         let link_static_crate = linkage == Linkage::Static
             || (linkage == Linkage::IncludedFromDylib || linkage == Linkage::NotLinked)
                 && (codegen_results.crate_info.compiler_builtins == Some(cnum)

Diff for: compiler/rustc_codegen_ssa/src/back/linker.rs

@@ -1744,15 +1744,10 @@ fn for_each_exported_symbols_include_dep<'tcx>(
     crate_type: CrateType,
     mut callback: impl FnMut(ExportedSymbol<'tcx>, SymbolExportInfo, CrateNum),
 ) {
-    for &(symbol, info) in tcx.exported_symbols(LOCAL_CRATE).iter() {
-        callback(symbol, info, LOCAL_CRATE);
-    }
-
     let formats = tcx.dependency_formats(());
     let deps = &formats[&crate_type];
 
-    for (index, dep_format) in deps.iter().enumerate() {
-        let cnum = CrateNum::new(index + 1);
+    for (cnum, dep_format) in deps.iter_enumerated() {
         // For each dependency that we are linking to statically ...
         if *dep_format == Linkage::Static {
             for &(symbol, info) in tcx.exported_symbols(cnum).iter() {

Diff for: compiler/rustc_driver_impl/src/pretty.rs

@@ -4,7 +4,6 @@ use std::cell::Cell;
 use std::fmt::Write;
 
 use rustc_ast_pretty::pprust as pprust_ast;
-use rustc_errors::FatalError;
 use rustc_middle::bug;
 use rustc_middle::mir::{write_mir_graphviz, write_mir_pretty};
 use rustc_middle::ty::{self, TyCtxt};
@@ -311,9 +310,7 @@ pub fn print<'tcx>(sess: &Session, ppm: PpMode, ex: PrintExtra<'tcx>) {
             let tcx = ex.tcx();
             let mut out = String::new();
             rustc_hir_analysis::check_crate(tcx);
-            if tcx.dcx().has_errors().is_some() {
-                FatalError.raise();
-            }
+            tcx.dcx().abort_if_errors();
             debug!("pretty printing THIR tree");
             for did in tcx.hir().body_owners() {
                 let _ = writeln!(out, "{:?}:\n{}\n", did, tcx.thir_tree(did));
@@ -324,9 +321,7 @@ pub fn print<'tcx>(sess: &Session, ppm: PpMode, ex: PrintExtra<'tcx>) {
             let tcx = ex.tcx();
             let mut out = String::new();
             rustc_hir_analysis::check_crate(tcx);
-            if tcx.dcx().has_errors().is_some() {
-                FatalError.raise();
-            }
+            tcx.dcx().abort_if_errors();
             debug!("pretty printing THIR flat");
             for did in tcx.hir().body_owners() {
                 let _ = writeln!(out, "{:?}:\n{}\n", did, tcx.thir_flat(did));

Diff for: compiler/rustc_errors/Cargo.toml

@@ -16,6 +16,7 @@ rustc_error_messages = { path = "../rustc_error_messages" }
 rustc_fluent_macro = { path = "../rustc_fluent_macro" }
 rustc_hir = { path = "../rustc_hir" }
 rustc_index = { path = "../rustc_index" }
+rustc_lexer = { path = "../rustc_lexer" }
 rustc_lint_defs = { path = "../rustc_lint_defs" }
 rustc_macros = { path = "../rustc_macros" }
 rustc_serialize = { path = "../rustc_serialize" }

Diff for: compiler/rustc_errors/src/emitter.rs

@@ -19,6 +19,7 @@ use derive_setters::Setters;
 use rustc_data_structures::fx::{FxHashMap, FxIndexMap, FxIndexSet};
 use rustc_data_structures::sync::{DynSend, IntoDynSyncSend, Lrc};
 use rustc_error_messages::{FluentArgs, SpanLabel};
+use rustc_lexer;
 use rustc_lint_defs::pluralize;
 use rustc_span::hygiene::{ExpnKind, MacroKind};
 use rustc_span::source_map::SourceMap;
@@ -1698,9 +1699,14 @@ impl HumanEmitter {
                     if let Some(source_string) =
                         line.line_index.checked_sub(1).and_then(|l| file.get_line(l))
                     {
+                        // Whitespace can only be removed (aka considered leading)
+                        // if the lexer considers it whitespace.
+                        // non-rustc_lexer::is_whitespace() chars are reported as an
+                        // error (ex. no-break-spaces \u{a0}), and thus can't be considered
+                        // for removal during error reporting.
                         let leading_whitespace = source_string
                             .chars()
-                            .take_while(|c| c.is_whitespace())
+                            .take_while(|c| rustc_lexer::is_whitespace(*c))
                             .map(|c| {
                                 match c {
                                     // Tabs are displayed as 4 spaces
@@ -1709,7 +1715,7 @@ impl HumanEmitter {
                                 }
                             })
                             .sum();
-                        if source_string.chars().any(|c| !c.is_whitespace()) {
+                        if source_string.chars().any(|c| !rustc_lexer::is_whitespace(c)) {
                             whitespace_margin = min(whitespace_margin, leading_whitespace);
                         }
                     }

Diff for: compiler/rustc_feature/src/builtin_attrs.rs

@@ -912,11 +912,20 @@ pub const BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[
     rustc_attr!(
         rustc_deny_explicit_impl,
         AttributeType::Normal,
-        template!(List: "implement_via_object = (true|false)"),
+        template!(Word),
         ErrorFollowing,
         EncodeCrossCrate::No,
         "#[rustc_deny_explicit_impl] enforces that a trait can have no user-provided impls"
     ),
+    rustc_attr!(
+        rustc_do_not_implement_via_object,
+        AttributeType::Normal,
+        template!(Word),
+        ErrorFollowing,
+        EncodeCrossCrate::No,
+        "#[rustc_do_not_implement_via_object] opts out of the automatic trait impl for trait objects \
+        (`impl Trait for dyn Trait`)"
+    ),
     rustc_attr!(
         rustc_has_incoherent_inherent_impls, AttributeType::Normal, template!(Word),
         ErrorFollowing, EncodeCrossCrate::Yes,