Merging upstream version 1.68.2+dfsg1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

12 files changed, 162 insertions, 209 deletions

diff --git a/compiler/rustc_metadata/src/creader.rs b/compiler/rustc_metadata/src/creader.rs
index efeaac8fe..653f2b39d 100644
--- a/compiler/rustc_metadata/src/creader.rs
+++ b/compiler/rustc_metadata/src/creader.rs
@@ -1,10 +1,9 @@
 //! Validates all used crates and extern libraries and loads their metadata
 
 use crate::errors::{
-    AllocFuncRequired, ConflictingAllocErrorHandler, ConflictingGlobalAlloc, CrateNotPanicRuntime,
-    GlobalAllocRequired, MissingAllocErrorHandler, NoMultipleAllocErrorHandler,
-    NoMultipleGlobalAlloc, NoPanicStrategy, NoTransitiveNeedsDep, NotProfilerRuntime,
-    ProfilerBuiltinsNeedsCore,
+    ConflictingAllocErrorHandler, ConflictingGlobalAlloc, CrateNotPanicRuntime,
+    GlobalAllocRequired, NoMultipleAllocErrorHandler, NoMultipleGlobalAlloc, NoPanicStrategy,
+    NoTransitiveNeedsDep, NotProfilerRuntime, ProfilerBuiltinsNeedsCore,
 };
 use crate::locator::{CrateError, CrateLocator, CratePaths};
 use crate::rmeta::{CrateDep, CrateMetadata, CrateNumMap, CrateRoot, MetadataBlob};
@@ -13,7 +12,7 @@ use rustc_ast::expand::allocator::AllocatorKind;
 use rustc_ast::{self as ast, *};
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_data_structures::svh::Svh;
-use rustc_data_structures::sync::Lrc;
+use rustc_data_structures::sync::{Lrc, ReadGuard};
 use rustc_expand::base::SyntaxExtension;
 use rustc_hir::def_id::{CrateNum, LocalDefId, StableCrateId, LOCAL_CRATE};
 use rustc_hir::definitions::Definitions;
@@ -68,11 +67,12 @@ impl std::fmt::Debug for CStore {
 pub struct CrateLoader<'a> {
     // Immutable configuration.
     sess: &'a Session,
-    metadata_loader: Box<MetadataLoaderDyn>,
+    metadata_loader: &'a MetadataLoaderDyn,
+    definitions: ReadGuard<'a, Definitions>,
     local_crate_name: Symbol,
     // Mutable output.
-    cstore: CStore,
-    used_extern_options: FxHashSet<Symbol>,
+    cstore: &'a mut CStore,
+    used_extern_options: &'a mut FxHashSet<Symbol>,
 }
 
 pub enum LoadedMacro {
@@ -112,7 +112,7 @@ impl<'a> std::fmt::Debug for CrateDump<'a> {
         writeln!(fmt, "resolved crates:")?;
         for (cnum, data) in self.0.iter_crate_data() {
             writeln!(fmt, "  name: {}", data.name())?;
-            writeln!(fmt, "  cnum: {}", cnum)?;
+            writeln!(fmt, "  cnum: {cnum}")?;
             writeln!(fmt, "  hash: {}", data.hash())?;
             writeln!(fmt, "  reqd: {:?}", data.dep_kind())?;
             let CrateSource { dylib, rlib, rmeta } = data.source();
@@ -150,7 +150,7 @@ impl CStore {
     pub(crate) fn get_crate_data(&self, cnum: CrateNum) -> CrateMetadataRef<'_> {
         let cdata = self.metas[cnum]
             .as_ref()
-            .unwrap_or_else(|| panic!("Failed to get crate data for {:?}", cnum));
+            .unwrap_or_else(|| panic!("Failed to get crate data for {cnum:?}"));
         CrateMetadataRef { cdata, cstore: self }
     }
 
@@ -239,47 +239,49 @@ impl CStore {
             );
         }
     }
+
+    pub fn new(sess: &Session) -> CStore {
+        let mut stable_crate_ids = FxHashMap::default();
+        stable_crate_ids.insert(sess.local_stable_crate_id(), LOCAL_CRATE);
+        CStore {
+            // We add an empty entry for LOCAL_CRATE (which maps to zero) in
+            // order to make array indices in `metas` match with the
+            // corresponding `CrateNum`. This first entry will always remain
+            // `None`.
+            metas: IndexVec::from_elem_n(None, 1),
+            injected_panic_runtime: None,
+            allocator_kind: None,
+            alloc_error_handler_kind: None,
+            has_global_allocator: false,
+            has_alloc_error_handler: false,
+            stable_crate_ids,
+            unused_externs: Vec::new(),
+        }
+    }
 }
 
 impl<'a> CrateLoader<'a> {
     pub fn new(
         sess: &'a Session,
-        metadata_loader: Box<MetadataLoaderDyn>,
+        metadata_loader: &'a MetadataLoaderDyn,
         local_crate_name: Symbol,
+        cstore: &'a mut CStore,
+        definitions: ReadGuard<'a, Definitions>,
+        used_extern_options: &'a mut FxHashSet<Symbol>,
     ) -> Self {
-        let mut stable_crate_ids = FxHashMap::default();
-        stable_crate_ids.insert(sess.local_stable_crate_id(), LOCAL_CRATE);
-
         CrateLoader {
             sess,
             metadata_loader,
             local_crate_name,
-            cstore: CStore {
-                // We add an empty entry for LOCAL_CRATE (which maps to zero) in
-                // order to make array indices in `metas` match with the
-                // corresponding `CrateNum`. This first entry will always remain
-                // `None`.
-                metas: IndexVec::from_elem_n(None, 1),
-                injected_panic_runtime: None,
-                allocator_kind: None,
-                alloc_error_handler_kind: None,
-                has_global_allocator: false,
-                has_alloc_error_handler: false,
-                stable_crate_ids,
-                unused_externs: Vec::new(),
-            },
-            used_extern_options: Default::default(),
+            cstore,
+            used_extern_options,
+            definitions,
         }
     }
-
     pub fn cstore(&self) -> &CStore {
         &self.cstore
     }
 
-    pub fn into_cstore(self) -> CStore {
-        self.cstore
-    }
-
     fn existing_match(&self, name: Symbol, hash: Option<Svh>, kind: PathKind) -> Option<CrateNum> {
         for (cnum, data) in self.cstore.iter_crate_data() {
             if data.name() != name {
@@ -518,8 +520,8 @@ impl<'a> CrateLoader<'a> {
         }))
     }
 
-    fn resolve_crate<'b>(
-        &'b mut self,
+    fn resolve_crate(
+        &mut self,
         name: Symbol,
         span: Span,
         dep_kind: CrateDepKind,
@@ -892,10 +894,6 @@ impl<'a> CrateLoader<'a> {
         } else {
             // The alloc crate provides a default allocation error handler if
             // one isn't specified.
-            if !self.sess.features_untracked().default_alloc_error_handler {
-                self.sess.emit_err(AllocFuncRequired);
-                self.sess.emit_note(MissingAllocErrorHandler);
-            }
             self.cstore.alloc_error_handler_kind = Some(AllocatorKind::Default);
         }
     }
@@ -989,7 +987,6 @@ impl<'a> CrateLoader<'a> {
     pub fn process_extern_crate(
         &mut self,
         item: &ast::Item,
-        definitions: &Definitions,
         def_id: LocalDefId,
     ) -> Option<CrateNum> {
         match item.kind {
@@ -1013,7 +1010,7 @@ impl<'a> CrateLoader<'a> {
 
                 let cnum = self.resolve_crate(name, item.span, dep_kind)?;
 
-                let path_len = definitions.def_path(def_id).data.len();
+                let path_len = self.definitions.def_path(def_id).data.len();
                 self.update_extern_crate(
                     cnum,
                     ExternCrate {
diff --git a/compiler/rustc_metadata/src/dependency_format.rs b/compiler/rustc_metadata/src/dependency_format.rs
index 6112ec9e4..cee4ba56a 100644
--- a/compiler/rustc_metadata/src/dependency_format.rs
+++ b/compiler/rustc_metadata/src/dependency_format.rs
@@ -54,7 +54,7 @@
 use crate::creader::CStore;
 use crate::errors::{
     BadPanicStrategy, CrateDepMultiple, IncompatiblePanicInDropStrategy, LibRequired,
-    RequiredPanicStrategy, RlibRequired, TwoPanicRuntimes,
+    RequiredPanicStrategy, RlibRequired, RustcLibRequired, TwoPanicRuntimes,
 };
 
 use rustc_data_structures::fx::FxHashMap;
@@ -224,7 +224,12 @@ fn calculate_type(tcx: TyCtxt<'_>, ty: CrateType) -> DependencyList {
                     Linkage::Static => "rlib",
                     _ => "dylib",
                 };
-                sess.emit_err(LibRequired { crate_name: tcx.crate_name(cnum), kind: kind });
+                let crate_name = tcx.crate_name(cnum);
+                if crate_name.as_str().starts_with("rustc_") {
+                    sess.emit_err(RustcLibRequired { crate_name, kind });
+                } else {
+                    sess.emit_err(LibRequired { crate_name, kind });
+                }
             }
         }
     }
diff --git a/compiler/rustc_metadata/src/errors.rs b/compiler/rustc_metadata/src/errors.rs
index 6f7e6e09c..02c03114e 100644
--- a/compiler/rustc_metadata/src/errors.rs
+++ b/compiler/rustc_metadata/src/errors.rs
@@ -25,6 +25,14 @@ pub struct LibRequired<'a> {
 }
 
 #[derive(Diagnostic)]
+#[diag(metadata_rustc_lib_required)]
+#[help]
+pub struct RustcLibRequired<'a> {
+    pub crate_name: Symbol,
+    pub kind: &'a str,
+}
+
+#[derive(Diagnostic)]
 #[diag(metadata_crate_dep_multiple)]
 #[help]
 pub struct CrateDepMultiple {
@@ -372,14 +380,6 @@ pub struct ConflictingAllocErrorHandler {
 pub struct GlobalAllocRequired;
 
 #[derive(Diagnostic)]
-#[diag(metadata_alloc_func_required)]
-pub struct AllocFuncRequired;
-
-#[derive(Diagnostic)]
-#[diag(metadata_missing_alloc_error_handler)]
-pub struct MissingAllocErrorHandler;
-
-#[derive(Diagnostic)]
 #[diag(metadata_no_transitive_needs_dep)]
 pub struct NoTransitiveNeedsDep<'a> {
     pub crate_name: Symbol,
@@ -494,26 +494,16 @@ impl IntoDiagnostic<'_> for MultipleCandidates {
         let mut diag = handler.struct_err(rustc_errors::fluent::metadata_multiple_candidates);
         diag.set_arg("crate_name", self.crate_name);
         diag.set_arg("flavor", self.flavor);
-        diag.code(error_code!(E0465));
+        diag.code(error_code!(E0464));
         diag.set_span(self.span);
         for (i, candidate) in self.candidates.iter().enumerate() {
-            diag.span_note(self.span, &format!("candidate #{}: {}", i + 1, candidate.display()));
+            diag.note(&format!("candidate #{}: {}", i + 1, candidate.display()));
         }
         diag
     }
 }
 
 #[derive(Diagnostic)]
-#[diag(metadata_multiple_matching_crates, code = "E0464")]
-#[note]
-pub struct MultipleMatchingCrates {
-    #[primary_span]
-    pub span: Span,
-    pub crate_name: Symbol,
-    pub candidates: String,
-}
-
-#[derive(Diagnostic)]
 #[diag(metadata_symbol_conflicts_current, code = "E0519")]
 pub struct SymbolConflictsCurrent {
     #[primary_span]
diff --git a/compiler/rustc_metadata/src/fs.rs b/compiler/rustc_metadata/src/fs.rs
index 7601f6bd3..f64318997 100644
--- a/compiler/rustc_metadata/src/fs.rs
+++ b/compiler/rustc_metadata/src/fs.rs
@@ -90,7 +90,7 @@ pub fn encode_and_write_metadata(tcx: TyCtxt<'_>) -> (EncodedMetadata, bool) {
     let _prof_timer = tcx.sess.prof.generic_activity("write_crate_metadata");
 
     // If the user requests metadata as output, rename `metadata_filename`
-    // to the expected output `out_filename`.  The match above should ensure
+    // to the expected output `out_filename`. The match above should ensure
     // this file always exists.
     let need_metadata_file = tcx.sess.opts.output_types.contains_key(&OutputType::Metadata);
     let (metadata_filename, metadata_tmpdir) = if need_metadata_file {
diff --git a/compiler/rustc_metadata/src/locator.rs b/compiler/rustc_metadata/src/locator.rs
index 15546092e..0f5f74007 100644
--- a/compiler/rustc_metadata/src/locator.rs
+++ b/compiler/rustc_metadata/src/locator.rs
@@ -216,9 +216,8 @@ use crate::creader::Library;
 use crate::errors::{
     CannotFindCrate, CrateLocationUnknownType, DlError, ExternLocationNotExist,
     ExternLocationNotFile, FoundStaticlib, IncompatibleRustc, InvalidMetadataFiles,
-    LibFilenameForm, MultipleCandidates, MultipleMatchingCrates, NewerCrateVersion,
-    NoCrateWithTriple, NoDylibPlugin, NonAsciiName, StableCrateIdCollision, SymbolConflictsCurrent,
-    SymbolConflictsOthers,
+    LibFilenameForm, MultipleCandidates, NewerCrateVersion, NoCrateWithTriple, NoDylibPlugin,
+    NonAsciiName, StableCrateIdCollision, SymbolConflictsCurrent, SymbolConflictsOthers,
 };
 use crate::rmeta::{rustc_version, MetadataBlob, METADATA_HEADER};
 
@@ -240,7 +239,6 @@ use rustc_target::spec::{Target, TargetTriple};
 
 use snap::read::FrameDecoder;
 use std::borrow::Cow;
-use std::fmt::Write as _;
 use std::io::{Read, Result as IoResult, Write};
 use std::path::{Path, PathBuf};
 use std::{cmp, fmt, fs};
@@ -482,7 +480,22 @@ impl<'a> CrateLocator<'a> {
         match libraries.len() {
             0 => Ok(None),
             1 => Ok(Some(libraries.into_iter().next().unwrap().1)),
-            _ => Err(CrateError::MultipleMatchingCrates(self.crate_name, libraries)),
+            _ => {
+                let mut libraries: Vec<_> = libraries.into_values().collect();
+
+                libraries.sort_by_cached_key(|lib| lib.source.paths().next().unwrap().clone());
+                let candidates = libraries
+                    .iter()
+                    .map(|lib| lib.source.paths().next().unwrap().clone())
+                    .collect::<Vec<_>>();
+
+                Err(CrateError::MultipleCandidates(
+                    self.crate_name,
+                    // these are the same for all candidates
+                    get_flavor_from_path(candidates.first().unwrap()),
+                    candidates,
+                ))
+            }
         }
     }
 
@@ -578,7 +591,7 @@ impl<'a> CrateLocator<'a> {
                     Err(MetadataError::LoadFailure(err)) => {
                         info!("no metadata found: {}", err);
                         // The file was present and created by the same compiler version, but we
-                        // couldn't load it for some reason.  Give a hard error instead of silently
+                        // couldn't load it for some reason. Give a hard error instead of silently
                         // ignoring it, but only if we would have given an error anyway.
                         self.crate_rejections
                             .via_invalid
@@ -882,17 +895,22 @@ pub fn list_file_metadata(
     metadata_loader: &dyn MetadataLoader,
     out: &mut dyn Write,
 ) -> IoResult<()> {
+    let flavor = get_flavor_from_path(path);
+    match get_metadata_section(target, flavor, path, metadata_loader) {
+        Ok(metadata) => metadata.list_crate_metadata(out),
+        Err(msg) => write!(out, "{}\n", msg),
+    }
+}
+
+fn get_flavor_from_path(path: &Path) -> CrateFlavor {
     let filename = path.file_name().unwrap().to_str().unwrap();
-    let flavor = if filename.ends_with(".rlib") {
+
+    if filename.ends_with(".rlib") {
         CrateFlavor::Rlib
     } else if filename.ends_with(".rmeta") {
         CrateFlavor::Rmeta
     } else {
         CrateFlavor::Dylib
-    };
-    match get_metadata_section(target, flavor, path, metadata_loader) {
-        Ok(metadata) => metadata.list_crate_metadata(out),
-        Err(msg) => write!(out, "{}\n", msg),
     }
 }
 
@@ -931,7 +949,6 @@ pub(crate) enum CrateError {
     ExternLocationNotExist(Symbol, PathBuf),
     ExternLocationNotFile(Symbol, PathBuf),
     MultipleCandidates(Symbol, CrateFlavor, Vec<PathBuf>),
-    MultipleMatchingCrates(Symbol, FxHashMap<Svh, Library>),
     SymbolConflictsCurrent(Symbol),
     SymbolConflictsOthers(Symbol),
     StableCrateIdCollision(Symbol, Symbol),
@@ -972,37 +989,7 @@ impl CrateError {
                 sess.emit_err(ExternLocationNotFile { span, crate_name, location: &loc });
             }
             CrateError::MultipleCandidates(crate_name, flavor, candidates) => {
-                sess.emit_err(MultipleCandidates { span, flavor: flavor, crate_name, candidates });
-            }
-            CrateError::MultipleMatchingCrates(crate_name, libraries) => {
-                let mut libraries: Vec<_> = libraries.into_values().collect();
-                // Make ordering of candidates deterministic.
-                // This has to `clone()` to work around lifetime restrictions with `sort_by_key()`.
-                // `sort_by()` could be used instead, but this is in the error path,
-                // so the performance shouldn't matter.
-                libraries.sort_by_cached_key(|lib| lib.source.paths().next().unwrap().clone());
-                let candidates = libraries
-                    .iter()
-                    .map(|lib| {
-                        let crate_name = lib.metadata.get_root().name();
-                        let crate_name = crate_name.as_str();
-                        let mut paths = lib.source.paths();
-
-                        // This `unwrap()` should be okay because there has to be at least one
-                        // source file. `CrateSource`'s docs confirm that too.
-                        let mut s = format!(
-                            "\ncrate `{}`: {}",
-                            crate_name,
-                            paths.next().unwrap().display()
-                        );
-                        let padding = 8 + crate_name.len();
-                        for path in paths {
-                            write!(s, "\n{:>padding$}", path.display(), padding = padding).unwrap();
-                        }
-                        s
-                    })
-                    .collect::<String>();
-                sess.emit_err(MultipleMatchingCrates { span, crate_name, candidates });
+                sess.emit_err(MultipleCandidates { span, crate_name, flavor, candidates });
             }
             CrateError::SymbolConflictsCurrent(root_name) => {
                 sess.emit_err(SymbolConflictsCurrent { span, crate_name: root_name });
@@ -1011,11 +998,7 @@ impl CrateError {
                 sess.emit_err(SymbolConflictsOthers { span, crate_name: root_name });
             }
             CrateError::StableCrateIdCollision(crate_name0, crate_name1) => {
-                sess.emit_err(StableCrateIdCollision {
-                    span,
-                    crate_name0: crate_name0,
-                    crate_name1: crate_name1,
-                });
+                sess.emit_err(StableCrateIdCollision { span, crate_name0, crate_name1 });
             }
             CrateError::DlOpen(s) | CrateError::DlSym(s) => {
                 sess.emit_err(DlError { span, err: s });
@@ -1074,7 +1057,7 @@ impl CrateError {
                     }
                     sess.emit_err(NoCrateWithTriple {
                         span,
-                        crate_name: crate_name,
+                        crate_name,
                         locator_triple: locator.triple.triple(),
                         add_info,
                         found_crates,
diff --git a/compiler/rustc_metadata/src/native_libs.rs b/compiler/rustc_metadata/src/native_libs.rs
index 1fd35adf1..6f05c76e8 100644
--- a/compiler/rustc_metadata/src/native_libs.rs
+++ b/compiler/rustc_metadata/src/native_libs.rs
@@ -45,7 +45,7 @@ pub fn find_native_static_library(
 
     for path in search_paths {
         for (prefix, suffix) in &formats {
-            let test = path.join(format!("{}{}{}", prefix, name, suffix));
+            let test = path.join(format!("{prefix}{name}{suffix}"));
             if test.exists() {
                 return test;
             }
@@ -433,10 +433,10 @@ impl<'tcx> Collector<'tcx> {
         }
 
         // Update kind and, optionally, the name of all native libraries
-        // (there may be more than one) with the specified name.  If any
+        // (there may be more than one) with the specified name. If any
         // library is mentioned more than once, keep the latest mention
         // of it, so that any possible dependent libraries appear before
-        // it.  (This ensures that the linker is able to see symbols from
+        // it. (This ensures that the linker is able to see symbols from
         // all possible dependent libraries before linking in the library
         // in question.)
         for passed_lib in &self.tcx.sess.opts.libs {
diff --git a/compiler/rustc_metadata/src/rmeta/decoder.rs b/compiler/rustc_metadata/src/rmeta/decoder.rs
index af7b0793a..143d8f2f1 100644
--- a/compiler/rustc_metadata/src/rmeta/decoder.rs
+++ b/compiler/rustc_metadata/src/rmeta/decoder.rs
@@ -78,10 +78,6 @@ pub(crate) struct CrateMetadata {
     blob: MetadataBlob,
 
     // --- Some data pre-decoded from the metadata blob, usually for performance ---
-    /// NOTE(eddyb) we pass `'static` to a `'tcx` parameter because this
-    /// lifetime is only used behind `LazyValue`, `LazyArray`, or `LazyTable`, and therefore acts like a
-    /// universal (`for<'tcx>`), that is paired up with whichever `TyCtxt`
-    /// is being used to decode those values.
     root: CrateRoot,
     /// Trait impl data.
     /// FIXME: Used only from queries and can use query cache,
@@ -466,7 +462,7 @@ impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for SyntaxContext {
                 .root
                 .syntax_contexts
                 .get(cdata, id)
-                .unwrap_or_else(|| panic!("Missing SyntaxContext {:?} for crate {:?}", id, cname))
+                .unwrap_or_else(|| panic!("Missing SyntaxContext {id:?} for crate {cname:?}"))
                 .decode((cdata, sess))
         })
     }
@@ -688,10 +684,10 @@ impl MetadataBlob {
     pub(crate) fn get_root(&self) -> CrateRoot {
         let slice = &self.blob()[..];
         let offset = METADATA_HEADER.len();
-        let pos = (((slice[offset + 0] as u32) << 24)
-            | ((slice[offset + 1] as u32) << 16)
-            | ((slice[offset + 2] as u32) << 8)
-            | ((slice[offset + 3] as u32) << 0)) as usize;
+
+        let pos_bytes = slice[offset..][..4].try_into().unwrap();
+        let pos = u32::from_be_bytes(pos_bytes) as usize;
+
         LazyValue::<CrateRoot>::from_position(NonZeroUsize::new(pos).unwrap()).decode(self)
     }
 
@@ -702,16 +698,14 @@ impl MetadataBlob {
         writeln!(out, "hash {} stable_crate_id {:?}", root.hash, root.stable_crate_id)?;
         writeln!(out, "proc_macro {:?}", root.proc_macro_data.is_some())?;
         writeln!(out, "=External Dependencies=")?;
+
         for (i, dep) in root.crate_deps.decode(self).enumerate() {
+            let CrateDep { name, extra_filename, hash, host_hash, kind } = dep;
+            let number = i + 1;
+
             writeln!(
                 out,
-                "{} {}{} hash {} host_hash {:?} kind {:?}",
-                i + 1,
-                dep.name,
-                dep.extra_filename,
-                dep.hash,
-                dep.host_hash,
-                dep.kind
+                "{number} {name}{extra_filename} hash {hash} host_hash {host_hash:?} kind {kind:?}"
             )?;
         }
         write!(out, "\n")?;
@@ -812,7 +806,7 @@ impl<'a, 'tcx> CrateMetadataRef<'a> {
             .tables
             .def_span
             .get(self, index)
-            .unwrap_or_else(|| panic!("Missing span for {:?}", index))
+            .unwrap_or_else(|| panic!("Missing span for {index:?}"))
             .decode((self, sess))
     }
 
@@ -1255,7 +1249,7 @@ impl<'a, 'tcx> CrateMetadataRef<'a> {
             .tables
             .proc_macro_quoted_spans
             .get(self, index)
-            .unwrap_or_else(|| panic!("Missing proc macro quoted span: {:?}", index))
+            .unwrap_or_else(|| panic!("Missing proc macro quoted span: {index:?}"))
             .decode((self, sess))
     }
 
@@ -1527,13 +1521,15 @@ impl<'a, 'tcx> CrateMetadataRef<'a> {
                 if let Some(virtual_dir) = &sess.opts.unstable_opts.simulate_remapped_rust_src_base
                 {
                     if let Some(real_dir) = &sess.opts.real_rust_source_base_dir {
-                        if let rustc_span::FileName::Real(ref mut old_name) = name {
-                            if let rustc_span::RealFileName::LocalPath(local) = old_name {
-                                if let Ok(rest) = local.strip_prefix(real_dir) {
-                                    *old_name = rustc_span::RealFileName::Remapped {
-                                        local_path: None,
-                                        virtual_name: virtual_dir.join(rest),
-                                    };
+                        for subdir in ["library", "compiler"] {
+                            if let rustc_span::FileName::Real(ref mut old_name) = name {
+                                if let rustc_span::RealFileName::LocalPath(local) = old_name {
+                                    if let Ok(rest) = local.strip_prefix(real_dir.join(subdir)) {
+                                        *old_name = rustc_span::RealFileName::Remapped {
+                                            local_path: None,
+                                            virtual_name: virtual_dir.join(subdir).join(rest),
+                                        };
+                                    }
                                 }
                             }
                         }
diff --git a/compiler/rustc_metadata/src/rmeta/decoder/cstore_impl.rs b/compiler/rustc_metadata/src/rmeta/decoder/cstore_impl.rs
index c5d4da079..6fd5bd52a 100644
--- a/compiler/rustc_metadata/src/rmeta/decoder/cstore_impl.rs
+++ b/compiler/rustc_metadata/src/rmeta/decoder/cstore_impl.rs
@@ -232,14 +232,14 @@ provide! { tcx, def_id, other, cdata,
             .get(cdata, def_id.index)
             .is_some()
     }
-    collect_trait_impl_trait_tys => {
+    collect_return_position_impl_trait_in_trait_tys => {
         Ok(cdata
             .root
             .tables
             .trait_impl_trait_tys
             .get(cdata, def_id.index)
             .map(|lazy| lazy.decode((cdata, tcx)))
-            .process_decoded(tcx, || panic!("{:?} does not have trait_impl_trait_tys", def_id)))
+            .process_decoded(tcx, || panic!("{def_id:?} does not have trait_impl_trait_tys")))
      }
 
     visibility => { cdata.get_visibility(def_id.index) }
@@ -391,7 +391,7 @@ pub(in crate::rmeta) fn provide(providers: &mut Providers) {
             // keys from the former.
             // This is a rudimentary check that does not catch all cases,
             // just the easiest.
-            let mut fallback_map: DefIdMap<DefId> = Default::default();
+            let mut fallback_map: Vec<(DefId, DefId)> = Default::default();
 
             // Issue 46112: We want the map to prefer the shortest
             // paths when reporting the path to an item. Therefore we
@@ -421,12 +421,12 @@ pub(in crate::rmeta) fn provide(providers: &mut Providers) {
 
                 if let Some(def_id) = child.res.opt_def_id() {
                     if child.ident.name == kw::Underscore {
-                        fallback_map.insert(def_id, parent);
+                        fallback_map.push((def_id, parent));
                         return;
                     }
 
                     if ty::util::is_doc_hidden(tcx, parent) {
-                        fallback_map.insert(def_id, parent);
+                        fallback_map.push((def_id, parent));
                         return;
                     }
 
@@ -460,6 +460,7 @@ pub(in crate::rmeta) fn provide(providers: &mut Providers) {
             // Fill in any missing entries with the less preferable path.
             // If this path re-exports the child as `_`, we still use this
             // path in a diagnostic that suggests importing `::*`.
+
             for (child, parent) in fallback_map {
                 visible_parent_map.entry(child).or_insert(parent);
             }
@@ -638,6 +639,9 @@ impl CrateStore for CStore {
     fn as_any(&self) -> &dyn Any {
         self
     }
+    fn untracked_as_any(&mut self) -> &mut dyn Any {
+        self
+    }
 
     fn crate_name(&self, cnum: CrateNum) -> Symbol {
         self.get_crate_data(cnum).root.name
diff --git a/compiler/rustc_metadata/src/rmeta/def_path_hash_map.rs b/compiler/rustc_metadata/src/rmeta/def_path_hash_map.rs
index 40c94b372..a6133f1b4 100644
--- a/compiler/rustc_metadata/src/rmeta/def_path_hash_map.rs
+++ b/compiler/rustc_metadata/src/rmeta/def_path_hash_map.rs
@@ -58,7 +58,7 @@ impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for DefPathHashMapRef<'static>
         let _ = d.read_raw_bytes(len);
 
         let inner = odht::HashTable::from_raw_bytes(o).unwrap_or_else(|e| {
-            panic!("decode error: {}", e);
+            panic!("decode error: {e}");
         });
         DefPathHashMapRef::OwnedFromMetadata(inner)
     }
diff --git a/compiler/rustc_metadata/src/rmeta/encoder.rs b/compiler/rustc_metadata/src/rmeta/encoder.rs
index 7304c891e..8f7a61b72 100644
--- a/compiler/rustc_metadata/src/rmeta/encoder.rs
+++ b/compiler/rustc_metadata/src/rmeta/encoder.rs
@@ -76,7 +76,7 @@ pub(super) struct EncodeContext<'a, 'tcx> {
     symbol_table: FxHashMap<Symbol, usize>,
 }
 
-/// If the current crate is a proc-macro, returns early with `Lazy:empty()`.
+/// If the current crate is a proc-macro, returns early with `LazyArray::empty()`.
 /// This is useful for skipping the encoding of things that aren't needed
 /// for proc-macro crates.
 macro_rules! empty_proc_macro {
@@ -145,7 +145,7 @@ impl<'a, 'tcx, I, T> Encodable<EncodeContext<'a, 'tcx>> for LazyTable<I, T> {
 impl<'a, 'tcx> Encodable<EncodeContext<'a, 'tcx>> for CrateNum {
     fn encode(&self, s: &mut EncodeContext<'a, 'tcx>) {
         if *self != LOCAL_CRATE && s.is_proc_macro {
-            panic!("Attempted to encode non-local CrateNum {:?} for proc-macro crate", self);
+            panic!("Attempted to encode non-local CrateNum {self:?} for proc-macro crate");
         }
         s.emit_u32(self.as_u32());
     }
@@ -172,7 +172,7 @@ impl<'a, 'tcx> Encodable<EncodeContext<'a, 'tcx>> for SyntaxContext {
 impl<'a, 'tcx> Encodable<EncodeContext<'a, 'tcx>> for ExpnId {
     fn encode(&self, s: &mut EncodeContext<'a, 'tcx>) {
         if self.krate == LOCAL_CRATE {
-            // We will only write details for local expansions.  Non-local expansions will fetch
+            // We will only write details for local expansions. Non-local expansions will fetch
             // data from the corresponding crate's metadata.
             // FIXME(#43047) FIXME(#74731) We may eventually want to avoid relying on external
             // metadata from proc-macro crates.
@@ -276,7 +276,7 @@ impl<'a, 'tcx> Encodable<EncodeContext<'a, 'tcx>> for Span {
                 // Introduce a new scope so that we drop the 'lock()' temporary
                 match &*source_file.external_src.lock() {
                     ExternalSource::Foreign { metadata_index, .. } => *metadata_index,
-                    src => panic!("Unexpected external source {:?}", src),
+                    src => panic!("Unexpected external source {src:?}"),
                 }
             };
 
@@ -332,7 +332,7 @@ impl<'a, 'tcx> Encodable<EncodeContext<'a, 'tcx>> for Symbol {
                     s.emit_str(self.as_str());
                 }
                 Entry::Occupied(o) => {
-                    let x = o.get().clone();
+                    let x = *o.get();
                     s.emit_u8(SYMBOL_OFFSET);
                     s.emit_usize(x);
                 }
@@ -713,7 +713,7 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
         let computed_total_bytes: usize = stats.iter().map(|(_, size)| size).sum();
         assert_eq!(total_bytes, computed_total_bytes);
 
-        if tcx.sess.meta_stats() {
+        if tcx.sess.opts.unstable_opts.meta_stats {
             self.opaque.flush();
 
             // Rewind and re-read all the metadata to count the zero bytes we wrote.
@@ -733,12 +733,9 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
             let prefix = "meta-stats";
             let perc = |bytes| (bytes * 100) as f64 / total_bytes as f64;
 
-            eprintln!("{} METADATA STATS", prefix);
+            eprintln!("{prefix} METADATA STATS");
             eprintln!("{} {:<23}{:>10}", prefix, "Section", "Size");
-            eprintln!(
-                "{} ----------------------------------------------------------------",
-                prefix
-            );
+            eprintln!("{prefix} ----------------------------------------------------------------");
             for (label, size) in stats {
                 eprintln!(
                     "{} {:<23}{:>10} ({:4.1}%)",
@@ -748,10 +745,7 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
                     perc(size)
                 );
             }
-            eprintln!(
-                "{} ----------------------------------------------------------------",
-                prefix
-            );
+            eprintln!("{prefix} ----------------------------------------------------------------");
             eprintln!(
                 "{} {:<23}{:>10} (of which {:.1}% are zero bytes)",
                 prefix,
@@ -759,7 +753,7 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
                 to_readable_str(total_bytes),
                 perc(zero_bytes)
             );
-            eprintln!("{}", prefix);
+            eprintln!("{prefix}");
         }
 
         root
@@ -894,8 +888,8 @@ fn should_encode_mir(tcx: TyCtxt<'_>, def_id: LocalDefId) -> (bool, bool) {
         | DefKind::AssocConst
         | DefKind::Static(..)
         | DefKind::Const => (true, false),
-        // Full-fledged functions
-        DefKind::AssocFn | DefKind::Fn => {
+        // Full-fledged functions + closures
+        DefKind::AssocFn | DefKind::Fn | DefKind::Closure => {
             let generics = tcx.generics_of(def_id);
             let needs_inline = (generics.requires_monomorphization(tcx)
                 || tcx.codegen_fn_attrs(def_id).requests_inline())
@@ -906,15 +900,6 @@ fn should_encode_mir(tcx: TyCtxt<'_>, def_id: LocalDefId) -> (bool, bool) {
             let always_encode_mir = tcx.sess.opts.unstable_opts.always_encode_mir;
             (is_const_fn, needs_inline || always_encode_mir)
         }
-        // Closures can't be const fn.
-        DefKind::Closure => {
-            let generics = tcx.generics_of(def_id);
-            let needs_inline = (generics.requires_monomorphization(tcx)
-                || tcx.codegen_fn_attrs(def_id).requests_inline())
-                && tcx.sess.opts.output_types.should_codegen();
-            let always_encode_mir = tcx.sess.opts.unstable_opts.always_encode_mir;
-            (false, needs_inline || always_encode_mir)
-        }
         // Generators require optimized MIR to compute layout.
         DefKind::Generator => (false, true),
         // The others don't have MIR.
@@ -1093,7 +1078,7 @@ fn should_encode_const(def_kind: DefKind) -> bool {
     }
 }
 
-fn should_encode_trait_impl_trait_tys<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> bool {
+fn should_encode_trait_impl_trait_tys(tcx: TyCtxt<'_>, def_id: DefId) -> bool {
     if tcx.def_kind(def_id) != DefKind::AssocFn {
         return false;
     }
@@ -1111,8 +1096,8 @@ fn should_encode_trait_impl_trait_tys<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) ->
     // associated types.
     tcx.fn_sig(trait_item_def_id).skip_binder().output().walk().any(|arg| {
         if let ty::GenericArgKind::Type(ty) = arg.unpack()
-            && let ty::Projection(data) = ty.kind()
-            && tcx.def_kind(data.item_def_id) == DefKind::ImplTraitPlaceholder
+            && let ty::Alias(ty::Projection, data) = ty.kind()
+            && tcx.def_kind(data.def_id) == DefKind::ImplTraitPlaceholder
         {
             true
         } else {
@@ -1197,13 +1182,16 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
                 record!(self.tables.params_in_repr[def_id] <- params_in_repr);
             }
             if should_encode_trait_impl_trait_tys(tcx, def_id)
-                && let Ok(table) = self.tcx.collect_trait_impl_trait_tys(def_id)
+                && let Ok(table) = self.tcx.collect_return_position_impl_trait_in_trait_tys(def_id)
             {
                 record!(self.tables.trait_impl_trait_tys[def_id] <- table);
             }
         }
-        let inherent_impls = tcx.crate_inherent_impls(());
-        for (def_id, implementations) in inherent_impls.inherent_impls.iter() {
+        let inherent_impls = tcx.with_stable_hashing_context(|hcx| {
+            tcx.crate_inherent_impls(()).inherent_impls.to_sorted(&hcx, true)
+        });
+
+        for (def_id, implementations) in inherent_impls {
             if implementations.is_empty() {
                 continue;
             }
@@ -1337,24 +1325,16 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
         debug!("EncodeContext::encode_info_for_trait_item({:?})", def_id);
         let tcx = self.tcx;
 
-        let ast_item = tcx.hir().expect_trait_item(def_id.expect_local());
-        self.tables.impl_defaultness.set(def_id.index, ast_item.defaultness);
+        let impl_defaultness = tcx.impl_defaultness(def_id.expect_local());
+        self.tables.impl_defaultness.set(def_id.index, impl_defaultness);
         let trait_item = tcx.associated_item(def_id);
         self.tables.assoc_container.set(def_id.index, trait_item.container);
 
         match trait_item.kind {
             ty::AssocKind::Const => {}
             ty::AssocKind::Fn => {
-                let hir::TraitItemKind::Fn(m_sig, m) = &ast_item.kind else { bug!() };
-                match *m {
-                    hir::TraitFn::Required(ref names) => {
-                        record_array!(self.tables.fn_arg_names[def_id] <- *names)
-                    }
-                    hir::TraitFn::Provided(body) => {
-                        record_array!(self.tables.fn_arg_names[def_id] <- self.tcx.hir().body_param_names(body))
-                    }
-                };
-                self.tables.asyncness.set(def_id.index, m_sig.header.asyncness);
+                record_array!(self.tables.fn_arg_names[def_id] <- tcx.fn_arg_names(def_id));
+                self.tables.asyncness.set(def_id.index, tcx.asyncness(def_id));
                 self.tables.constness.set(def_id.index, hir::Constness::NotConst);
             }
             ty::AssocKind::Type => {
@@ -1443,7 +1423,7 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
             let instance =
                 ty::InstanceDef::Item(ty::WithOptConstParam::unknown(def_id.to_def_id()));
             let unused = tcx.unused_generic_params(instance);
-            if !unused.is_empty() {
+            if !unused.all_used() {
                 record!(self.tables.unused_generic_params[def_id.to_def_id()] <- unused);
             }
         }
@@ -1572,10 +1552,10 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
                 self.tables.impl_defaultness.set(def_id.index, *defaultness);
                 self.tables.constness.set(def_id.index, *constness);
 
-                let trait_ref = self.tcx.impl_trait_ref(def_id);
+                let trait_ref = self.tcx.impl_trait_ref(def_id).map(ty::EarlyBinder::skip_binder);
                 if let Some(trait_ref) = trait_ref {
                     let trait_def = self.tcx.trait_def(trait_ref.def_id);
-                    if let Some(mut an) = trait_def.ancestors(self.tcx, def_id).ok() {
+                    if let Ok(mut an) = trait_def.ancestors(self.tcx, def_id) {
                         if let Some(specialization_graph::Node::Impl(parent)) = an.nth(1) {
                             self.tables.impl_parent.set(def_id.index, parent.into());
                         }
@@ -1703,6 +1683,8 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
             }
 
             ty::Closure(_, substs) => {
+                let constness = self.tcx.constness(def_id.to_def_id());
+                self.tables.constness.set(def_id.to_def_id().index, constness);
                 record!(self.tables.fn_sig[def_id.to_def_id()] <- substs.as_closure().sig());
             }
 
@@ -1860,7 +1842,7 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
         // the assumption that they are numbered 1 to n.
         // FIXME (#2166): This is not nearly enough to support correct versioning
         // but is enough to get transitive crate dependencies working.
-        self.lazy_array(deps.iter().map(|&(_, ref dep)| dep))
+        self.lazy_array(deps.iter().map(|(_, dep)| dep))
     }
 
     fn encode_lib_features(&mut self) -> LazyArray<(Symbol, Option<Symbol>)> {
@@ -1914,6 +1896,8 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
         for id in tcx.hir().items() {
             if matches!(tcx.def_kind(id.owner_id), DefKind::Impl) {
                 if let Some(trait_ref) = tcx.impl_trait_ref(id.owner_id) {
+                    let trait_ref = trait_ref.subst_identity();
+
                     let simplified_self_ty = fast_reject::simplify_type(
                         self.tcx,
                         trait_ref.self_ty(),
@@ -1997,7 +1981,7 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
         self.lazy_array(
             exported_symbols
                 .iter()
-                .filter(|&&(ref exported_symbol, _)| match *exported_symbol {
+                .filter(|&(exported_symbol, _)| match *exported_symbol {
                     ExportedSymbol::NoDefId(symbol_name) => symbol_name != metadata_symbol_name,
                     _ => true,
                 })
diff --git a/compiler/rustc_metadata/src/rmeta/mod.rs b/compiler/rustc_metadata/src/rmeta/mod.rs
index 571804644..5066dbbb9 100644
--- a/compiler/rustc_metadata/src/rmeta/mod.rs
+++ b/compiler/rustc_metadata/src/rmeta/mod.rs
@@ -13,7 +13,7 @@ use rustc_hir::def::{CtorKind, DefKind};
 use rustc_hir::def_id::{CrateNum, DefId, DefIndex, DefPathHash, StableCrateId};
 use rustc_hir::definitions::DefKey;
 use rustc_hir::lang_items::LangItem;
-use rustc_index::bit_set::{BitSet, FiniteBitSet};
+use rustc_index::bit_set::BitSet;
 use rustc_index::vec::IndexVec;
 use rustc_middle::metadata::ModChild;
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrs;
@@ -22,7 +22,7 @@ use rustc_middle::middle::resolve_lifetime::ObjectLifetimeDefault;
 use rustc_middle::mir;
 use rustc_middle::ty::fast_reject::SimplifiedType;
 use rustc_middle::ty::query::Providers;
-use rustc_middle::ty::{self, ReprOptions, Ty};
+use rustc_middle::ty::{self, ReprOptions, Ty, UnusedGenericParams};
 use rustc_middle::ty::{DeducedParamAttrs, GeneratorDiagnosticData, ParameterizedOverTcx, TyCtxt};
 use rustc_serialize::opaque::FileEncoder;
 use rustc_session::config::SymbolManglingVersion;
@@ -359,8 +359,8 @@ define_tables! {
     variances_of: Table<DefIndex, LazyArray<ty::Variance>>,
     fn_sig: Table<DefIndex, LazyValue<ty::PolyFnSig<'static>>>,
     codegen_fn_attrs: Table<DefIndex, LazyValue<CodegenFnAttrs>>,
-    impl_trait_ref: Table<DefIndex, LazyValue<ty::TraitRef<'static>>>,
-    const_param_default: Table<DefIndex, LazyValue<rustc_middle::ty::Const<'static>>>,
+    impl_trait_ref: Table<DefIndex, LazyValue<ty::EarlyBinder<ty::TraitRef<'static>>>>,
+    const_param_default: Table<DefIndex, LazyValue<ty::EarlyBinder<rustc_middle::ty::Const<'static>>>>,
     object_lifetime_default: Table<DefIndex, LazyValue<ObjectLifetimeDefault>>,
     optimized_mir: Table<DefIndex, LazyValue<mir::Body<'static>>>,
     mir_for_ctfe: Table<DefIndex, LazyValue<mir::Body<'static>>>,
@@ -384,7 +384,7 @@ define_tables! {
     trait_item_def_id: Table<DefIndex, RawDefId>,
     inherent_impls: Table<DefIndex, LazyArray<DefIndex>>,
     expn_that_defined: Table<DefIndex, LazyValue<ExpnId>>,
-    unused_generic_params: Table<DefIndex, LazyValue<FiniteBitSet<u32>>>,
+    unused_generic_params: Table<DefIndex, LazyValue<UnusedGenericParams>>,
     params_in_repr: Table<DefIndex, LazyValue<BitSet<u32>>>,
     repr_options: Table<DefIndex, LazyValue<ReprOptions>>,
     // `def_keys` and `def_path_hashes` represent a lazy version of a
@@ -418,11 +418,6 @@ struct VariantData {
     is_non_exhaustive: bool,
 }
 
-#[derive(TyEncodable, TyDecodable)]
-struct GeneratorData<'tcx> {
-    layout: mir::GeneratorLayout<'tcx>,
-}
-
 // Tags used for encoding Spans:
 const TAG_VALID_SPAN_LOCAL: u8 = 0;
 const TAG_VALID_SPAN_FOREIGN: u8 = 1;
diff --git a/compiler/rustc_metadata/src/rmeta/table.rs b/compiler/rustc_metadata/src/rmeta/table.rs
index 29fe61107..716655c7f 100644
--- a/compiler/rustc_metadata/src/rmeta/table.rs
+++ b/compiler/rustc_metadata/src/rmeta/table.rs
@@ -7,7 +7,6 @@ use rustc_middle::ty::ParameterizedOverTcx;
 use rustc_serialize::opaque::FileEncoder;
 use rustc_serialize::Encoder as _;
 use rustc_span::hygiene::MacroKind;
-use std::convert::TryInto;
 use std::marker::PhantomData;
 use std::num::NonZeroUsize;