diff --git a/compiler/rustc_ast_lowering/src/index.rs b/compiler/rustc_ast_lowering/src/index.rs
index 5f8933aa2beba..8d7351d3a510c 100644
--- a/compiler/rustc_ast_lowering/src/index.rs
+++ b/compiler/rustc_ast_lowering/src/index.rs
@@ -125,9 +125,9 @@ impl<'a, 'hir> NodeCollector<'a, 'hir> {
 }
 
 impl<'a, 'hir> Visitor<'hir> for NodeCollector<'a, 'hir> {
-    /// Because we want to track parent items and so forth, enable
-    /// deep walking so that we walk nested items in the context of
-    /// their outer items.
+    // Because we want to track parent items and so forth, enable
+    // deep walking so that we walk nested items in the context of
+    // their outer items.
 
     fn visit_nested_item(&mut self, item: ItemId) {
         debug!("visit_nested_item: {:?}", item);
diff --git a/compiler/rustc_attr_parsing/src/attributes/cfg_select.rs b/compiler/rustc_attr_parsing/src/attributes/cfg_select.rs
new file mode 100644
index 0000000000000..8006fb963b198
--- /dev/null
+++ b/compiler/rustc_attr_parsing/src/attributes/cfg_select.rs
@@ -0,0 +1,89 @@
+use rustc_ast::token::Token;
+use rustc_ast::tokenstream::TokenStream;
+use rustc_ast::{AttrStyle, NodeId, token};
+use rustc_feature::{AttributeTemplate, Features};
+use rustc_hir::AttrPath;
+use rustc_hir::attrs::CfgEntry;
+use rustc_parse::exp;
+use rustc_parse::parser::Parser;
+use rustc_session::Session;
+use rustc_span::{ErrorGuaranteed, Ident, Span};
+
+use crate::parser::MetaItemOrLitParser;
+use crate::{AttributeParser, ParsedDescription, ShouldEmit, parse_cfg_entry};
+
+pub enum CfgSelectPredicate {
+    Cfg(CfgEntry),
+    Wildcard(Token),
+}
+
+#[derive(Default)]
+pub struct CfgSelectBranches {
+    /// All the conditional branches.
+    pub reachable: Vec<(CfgEntry, TokenStream, Span)>,
+    /// The first wildcard `_ => { ... }` branch.
+    pub wildcard: Option<(Token, TokenStream, Span)>,
+    /// All branches after the first wildcard, including further wildcards.
+    /// These branches are kept for formatting.
+    pub unreachable: Vec<(CfgSelectPredicate, TokenStream, Span)>,
+}
+
+pub fn parse_cfg_select(
+    p: &mut Parser<'_>,
+    sess: &Session,
+    features: Option<&Features>,
+    lint_node_id: NodeId,
+) -> Result<CfgSelectBranches, ErrorGuaranteed> {
+    let mut branches = CfgSelectBranches::default();
+
+    while p.token != token::Eof {
+        if p.eat_keyword(exp!(Underscore)) {
+            let underscore = p.prev_token;
+            p.expect(exp!(FatArrow)).map_err(|e| e.emit())?;
+
+            let tts = p.parse_delimited_token_tree().map_err(|e| e.emit())?;
+            let span = underscore.span.to(p.token.span);
+
+            match branches.wildcard {
+                None => branches.wildcard = Some((underscore, tts, span)),
+                Some(_) => {
+                    branches.unreachable.push((CfgSelectPredicate::Wildcard(underscore), tts, span))
+                }
+            }
+        } else {
+            let meta = MetaItemOrLitParser::parse_single(p, ShouldEmit::ErrorsAndLints)
+                .map_err(|diag| diag.emit())?;
+            let cfg_span = meta.span();
+            let cfg = AttributeParser::parse_single_args(
+                sess,
+                cfg_span,
+                cfg_span,
+                AttrStyle::Inner,
+                AttrPath {
+                    segments: vec![Ident::from_str("cfg_select")].into_boxed_slice(),
+                    span: cfg_span,
+                },
+                ParsedDescription::Macro,
+                cfg_span,
+                lint_node_id,
+                features,
+                ShouldEmit::ErrorsAndLints,
+                &meta,
+                parse_cfg_entry,
+                &AttributeTemplate::default(),
+            )?;
+
+            p.expect(exp!(FatArrow)).map_err(|e| e.emit())?;
+
+            let tts = p.parse_delimited_token_tree().map_err(|e| e.emit())?;
+            let span = cfg_span.to(p.token.span);
+
+            match branches.wildcard {
+                None => branches.reachable.push((cfg, tts, span)),
+                Some(_) => branches.unreachable.push((CfgSelectPredicate::Cfg(cfg), tts, span)),
+            }
+        }
+    }
+
+    Ok(branches)
+}
diff --git a/compiler/rustc_attr_parsing/src/attributes/mod.rs b/compiler/rustc_attr_parsing/src/attributes/mod.rs
index 093969586596d..65e0957ca9005 100644
--- a/compiler/rustc_attr_parsing/src/attributes/mod.rs
+++ b/compiler/rustc_attr_parsing/src/attributes/mod.rs
@@ -33,6 +33,7 @@ pub(crate) mod allow_unstable;
 pub(crate) mod body;
 pub(crate) mod cfg;
 pub(crate) mod cfg_old;
+pub(crate) mod cfg_select;
 pub(crate) mod codegen_attrs;
 pub(crate) mod confusables;
 pub(crate) mod crate_level;
diff --git a/compiler/rustc_attr_parsing/src/lib.rs b/compiler/rustc_attr_parsing/src/lib.rs
index 473935abdcd50..046cca4c742b0 100644
--- a/compiler/rustc_attr_parsing/src/lib.rs
+++ b/compiler/rustc_attr_parsing/src/lib.rs
@@ -106,6 +106,7 @@ pub use attributes::cfg::{
     CFG_TEMPLATE, EvalConfigResult, eval_config_entry, parse_cfg, parse_cfg_attr, parse_cfg_entry,
 };
 pub use attributes::cfg_old::*;
+pub use attributes::cfg_select::*;
 pub use attributes::util::{is_builtin_attr, is_doc_alias_attrs_contain_symbol, parse_version};
 pub use context::{Early, Late, OmitDoc, ShouldEmit};
 pub use interface::AttributeParser;
diff --git a/compiler/rustc_builtin_macros/src/cfg_select.rs b/compiler/rustc_builtin_macros/src/cfg_select.rs
index f22d5f255c292..f2e454c3d4373 100644
--- a/compiler/rustc_builtin_macros/src/cfg_select.rs
+++ b/compiler/rustc_builtin_macros/src/cfg_select.rs
@@ -1,7 +1,9 @@
 use rustc_ast::tokenstream::TokenStream;
 use rustc_attr_parsing as attr;
+use rustc_attr_parsing::{
+    CfgSelectBranches, CfgSelectPredicate, EvalConfigResult, ShouldEmit, parse_cfg_select,
+};
 use rustc_expand::base::{DummyResult, ExpandResult, ExtCtxt, MacroExpanderResult};
-use rustc_parse::parser::cfg_select::{CfgSelectBranches, CfgSelectPredicate, parse_cfg_select};
 use rustc_span::{Ident, Span, sym};
 
 use crate::errors::{CfgSelectNoMatches, CfgSelectUnreachable};
@@ -9,11 +11,11 @@ use crate::errors::{CfgSelectNoMatches, CfgSelectUnreachable};
 /// Selects the first arm whose predicate evaluates to true.
 fn select_arm(ecx: &ExtCtxt<'_>, branches: CfgSelectBranches) -> Option<(TokenStream, Span)> {
     for (cfg, tt, arm_span) in branches.reachable {
-        if attr::cfg_matches(
-            &cfg,
+        if let EvalConfigResult::True = attr::eval_config_entry(
             &ecx.sess,
+            &cfg,
             ecx.current_expansion.lint_node_id,
-            Some(ecx.ecfg.features),
+            ShouldEmit::ErrorsAndLints,
         ) {
             return Some((tt, arm_span));
         }
@@ -27,37 +29,41 @@ pub(super) fn expand_cfg_select<'cx>(
     sp: Span,
     tts: TokenStream,
 ) -> MacroExpanderResult<'cx> {
-    ExpandResult::Ready(match parse_cfg_select(&mut ecx.new_parser_from_tts(tts)) {
-        Ok(branches) => {
-            if let Some((underscore, _, _)) = branches.wildcard {
-                // Warn for every unreachable predicate. We store the fully parsed branch for rustfmt.
-                for (predicate, _, _) in &branches.unreachable {
-                    let span = match predicate {
-                        CfgSelectPredicate::Wildcard(underscore) => underscore.span,
-                        CfgSelectPredicate::Cfg(cfg) => cfg.span(),
-                    };
-                    let err = CfgSelectUnreachable { span, wildcard_span: underscore.span };
-                    ecx.dcx().emit_warn(err);
+    ExpandResult::Ready(
+        match parse_cfg_select(
+            &mut ecx.new_parser_from_tts(tts),
+            ecx.sess,
+            Some(ecx.ecfg.features),
+            ecx.current_expansion.lint_node_id,
+        ) {
+            Ok(branches) => {
+                if let Some((underscore, _, _)) = branches.wildcard {
+                    // Warn for every unreachable predicate. We store the fully parsed branch for rustfmt.
+                    for (predicate, _, _) in &branches.unreachable {
+                        let span = match predicate {
+                            CfgSelectPredicate::Wildcard(underscore) => underscore.span,
+                            CfgSelectPredicate::Cfg(cfg) => cfg.span(),
+                        };
+                        let err = CfgSelectUnreachable { span, wildcard_span: underscore.span };
+                        ecx.dcx().emit_warn(err);
+                    }
                 }
-            }
 
-            if let Some((tts, arm_span)) = select_arm(ecx, branches) {
-                return ExpandResult::from_tts(
-                    ecx,
-                    tts,
-                    sp,
-                    arm_span,
-                    Ident::with_dummy_span(sym::cfg_select),
-                );
-            } else {
-                // Emit a compiler error when none of the predicates matched.
-                let guar = ecx.dcx().emit_err(CfgSelectNoMatches { span: sp });
-                DummyResult::any(sp, guar)
+                if let Some((tts, arm_span)) = select_arm(ecx, branches) {
+                    return ExpandResult::from_tts(
+                        ecx,
+                        tts,
+                        sp,
+                        arm_span,
+                        Ident::with_dummy_span(sym::cfg_select),
+                    );
+                } else {
+                    // Emit a compiler error when none of the predicates matched.
+                    let guar = ecx.dcx().emit_err(CfgSelectNoMatches { span: sp });
+                    DummyResult::any(sp, guar)
+                }
             }
-        }
-        Err(err) => {
-            let guar = err.emit();
-            DummyResult::any(sp, guar)
-        }
-    })
+            Err(guar) => DummyResult::any(sp, guar),
+        },
+    )
 }
diff --git a/compiler/rustc_codegen_cranelift/src/abi/mod.rs b/compiler/rustc_codegen_cranelift/src/abi/mod.rs
index 9ac282df5b5ea..09d71f5dd5579 100644
--- a/compiler/rustc_codegen_cranelift/src/abi/mod.rs
+++ b/compiler/rustc_codegen_cranelift/src/abi/mod.rs
@@ -916,8 +916,8 @@ pub(crate) fn codegen_call_with_unwind_action(
 pub(crate) fn lib_call_arg_param(tcx: TyCtxt<'_>, ty: Type, is_signed: bool) -> AbiParam {
     let param = AbiParam::new(ty);
     if ty.is_int() && u64::from(ty.bits()) < tcx.data_layout.pointer_size().bits() {
-        match (&tcx.sess.target.arch, tcx.sess.target.vendor.as_ref()) {
-            (Arch::X86_64, _) | (Arch::AArch64, "apple") => match (ty, is_signed) {
+        match (&tcx.sess.target.arch, tcx.sess.target.is_like_darwin) {
+            (Arch::X86_64, _) | (Arch::AArch64, true) => match (ty, is_signed) {
                 (types::I8 | types::I16, true) => param.sext(),
                 (types::I8 | types::I16, false) => param.uext(),
                 _ => param,
diff --git a/compiler/rustc_codegen_cranelift/src/codegen_f16_f128.rs b/compiler/rustc_codegen_cranelift/src/codegen_f16_f128.rs
index 91f7220667ff9..86bff32dc623c 100644
--- a/compiler/rustc_codegen_cranelift/src/codegen_f16_f128.rs
+++ b/compiler/rustc_codegen_cranelift/src/codegen_f16_f128.rs
@@ -5,7 +5,7 @@ use crate::prelude::*;
 
 pub(crate) fn f16_to_f32(fx: &mut FunctionCx<'_, '_, '_>, value: Value) -> Value {
     let (value, arg_ty) =
-        if fx.tcx.sess.target.vendor == "apple" && fx.tcx.sess.target.arch == Arch::X86_64 {
+        if fx.tcx.sess.target.is_like_darwin && fx.tcx.sess.target.arch == Arch::X86_64 {
             (
                 fx.bcx.ins().bitcast(types::I16, MemFlags::new(), value),
                 lib_call_arg_param(fx.tcx, types::I16, false),
@@ -22,8 +22,7 @@ fn f16_to_f64(fx: &mut FunctionCx<'_, '_, '_>, value: Value) -> Value {
 }
 
 pub(crate) fn f32_to_f16(fx: &mut FunctionCx<'_, '_, '_>, value: Value) -> Value {
-    let ret_ty = if fx.tcx.sess.target.vendor == "apple" && fx.tcx.sess.target.arch == Arch::X86_64
-    {
+    let ret_ty = if fx.tcx.sess.target.is_like_darwin && fx.tcx.sess.target.arch == Arch::X86_64 {
         types::I16
     } else {
         types::F16
@@ -38,8 +37,7 @@ pub(crate) fn f32_to_f16(fx: &mut FunctionCx<'_, '_, '_>, value: Value) -> Value
 }
 
 fn f64_to_f16(fx: &mut FunctionCx<'_, '_, '_>, value: Value) -> Value {
-    let ret_ty = if fx.tcx.sess.target.vendor == "apple" && fx.tcx.sess.target.arch == Arch::X86_64
-    {
+    let ret_ty = if fx.tcx.sess.target.is_like_darwin && fx.tcx.sess.target.arch == Arch::X86_64 {
         types::I16
     } else {
         types::F16
diff --git a/compiler/rustc_codegen_ssa/src/back/link.rs b/compiler/rustc_codegen_ssa/src/back/link.rs
index c5724c20b2165..2817dcf8e976a 100644
--- a/compiler/rustc_codegen_ssa/src/back/link.rs
+++ b/compiler/rustc_codegen_ssa/src/back/link.rs
@@ -1819,7 +1819,7 @@ fn self_contained_components(
                 LinkSelfContainedDefault::InferredForMusl => sess.crt_static(Some(crate_type)),
                 LinkSelfContainedDefault::InferredForMingw => {
                     sess.host == sess.target
-                        && sess.target.vendor != "uwp"
+                        && sess.target.abi != "uwp"
                         && detect_self_contained_mingw(sess, linker)
                 }
             }
diff --git a/compiler/rustc_codegen_ssa/src/back/linker.rs b/compiler/rustc_codegen_ssa/src/back/linker.rs
index eb2740d59b4b5..5abcf99b3d67a 100644
--- a/compiler/rustc_codegen_ssa/src/back/linker.rs
+++ b/compiler/rustc_codegen_ssa/src/back/linker.rs
@@ -83,7 +83,7 @@ pub(crate) fn get_linker<'a>(
     // To comply with the Windows App Certification Kit,
     // MSVC needs to link with the Store versions of the runtime libraries (vcruntime, msvcrt, etc).
     let t = &sess.target;
-    if matches!(flavor, LinkerFlavor::Msvc(..)) && t.vendor == "uwp" {
+    if matches!(flavor, LinkerFlavor::Msvc(..)) && t.abi == "uwp" {
         if let Some(ref tool) = msvc_tool {
             let original_path = tool.path();
             if let Some(root_lib_path) = original_path.ancestors().nth(4) {
@@ -134,7 +134,7 @@ pub(crate) fn get_linker<'a>(
 
     // FIXME: Move `/LIBPATH` addition for uwp targets from the linker construction
     // to the linker args construction.
-    assert!(cmd.get_args().is_empty() || sess.target.vendor == "uwp");
+    assert!(cmd.get_args().is_empty() || sess.target.abi == "uwp");
     match flavor {
         LinkerFlavor::Unix(Cc::No) if sess.target.os == "l4re" => {
             Box::new(L4Bender::new(cmd, sess)) as Box<dyn Linker>
diff --git a/compiler/rustc_codegen_ssa/src/common.rs b/compiler/rustc_codegen_ssa/src/common.rs
index 08e2f35595332..bde36f45b3838 100644
--- a/compiler/rustc_codegen_ssa/src/common.rs
+++ b/compiler/rustc_codegen_ssa/src/common.rs
@@ -171,7 +171,7 @@ pub fn asm_const_to_str<'tcx>(
 }
 
 pub fn is_mingw_gnu_toolchain(target: &Target) -> bool {
-    target.vendor == "pc" && target.os == "windows" && target.env == "gnu" && target.abi.is_empty()
+    target.os == "windows" && target.env == "gnu" && target.abi.is_empty()
 }
 
 pub fn i686_decorated_name(
diff --git a/compiler/rustc_data_structures/src/marker.rs b/compiler/rustc_data_structures/src/marker.rs
index 2be9ba292f976..0ef3bb319ff80 100644
--- a/compiler/rustc_data_structures/src/marker.rs
+++ b/compiler/rustc_data_structures/src/marker.rs
@@ -53,13 +53,13 @@ impl !DynSend for std::env::VarsOs {}
 
 macro_rules! already_send {
     ($([$ty: ty])*) => {
-        $(unsafe impl DynSend for $ty where $ty: Send {})*
+        $(unsafe impl DynSend for $ty where Self: Send {})*
     };
 }
 
 // These structures are already `Send`.
 already_send!(
-    [std::backtrace::Backtrace][std::io::Stdout][std::io::Stderr][std::io::Error][std::fs::File]
+    [std::backtrace::Backtrace][std::io::Stdout][std::io::Stderr][std::io::Error][std::fs::File][std::panic::Location<'_>]
         [rustc_arena::DroplessArena][jobserver_crate::Client][jobserver_crate::HelperThread]
         [crate::memmap::Mmap][crate::profiling::SelfProfiler][crate::owned_slice::OwnedSlice]
 );
@@ -127,14 +127,14 @@ impl !DynSync for std::env::VarsOs {}
 
 macro_rules! already_sync {
     ($([$ty: ty])*) => {
-        $(unsafe impl DynSync for $ty where $ty: Sync {})*
+        $(unsafe impl DynSync for $ty where Self: Sync {})*
     };
 }
 
 // These structures are already `Sync`.
 already_sync!(
     [std::sync::atomic::AtomicBool][std::sync::atomic::AtomicUsize][std::sync::atomic::AtomicU8]
-        [std::sync::atomic::AtomicU32][std::backtrace::Backtrace][std::io::Error][std::fs::File]
+        [std::sync::atomic::AtomicU32][std::backtrace::Backtrace][std::io::Error][std::fs::File][std::panic::Location<'_>]
         [jobserver_crate::Client][jobserver_crate::HelperThread][crate::memmap::Mmap]
         [crate::profiling::SelfProfiler][crate::owned_slice::OwnedSlice]
 );
diff --git a/compiler/rustc_data_structures/src/steal.rs b/compiler/rustc_data_structures/src/steal.rs
index 0d79d98b5d966..afa9bc36f2c5e 100644
--- a/compiler/rustc_data_structures/src/steal.rs
+++ b/compiler/rustc_data_structures/src/steal.rs
@@ -1,5 +1,5 @@
 use crate::stable_hasher::{HashStable, StableHasher};
-use crate::sync::{MappedReadGuard, ReadGuard, RwLock};
+use crate::sync::{MappedReadGuard, MappedWriteGuard, ReadGuard, RwLock, WriteGuard};
 
 /// The `Steal` struct is intended to used as the value for a query.
 /// Specifically, we sometimes have queries (*cough* MIR *cough*)
@@ -40,9 +40,17 @@ impl<T> Steal<T> {
         ReadGuard::map(borrow, |opt| opt.as_ref().unwrap())
     }
 
+    /// An escape hatch for rustc drivers to mutate `Steal` caches.
+    ///
+    /// Use at your own risk. This can badly break incremental compilation
+    /// and anything else that relies on the immutability of query caches.
     #[track_caller]
-    pub fn get_mut(&mut self) -> &mut T {
-        self.value.get_mut().as_mut().expect("attempt to read from stolen value")
+    pub fn risky_hack_borrow_mut(&self) -> MappedWriteGuard<'_, T> {
+        let borrow = self.value.borrow_mut();
+        if borrow.is_none() {
+            panic!("attempted to read from stolen value: {}", std::any::type_name::<T>());
+        }
+        WriteGuard::map(borrow, |opt| opt.as_mut().unwrap())
     }
 
     #[track_caller]
diff --git a/compiler/rustc_errors/src/emitter.rs b/compiler/rustc_errors/src/emitter.rs
index 81a7ee1ff45fe..e6fa1fa5ce50a 100644
--- a/compiler/rustc_errors/src/emitter.rs
+++ b/compiler/rustc_errors/src/emitter.rs
@@ -2322,11 +2322,6 @@ impl HumanEmitter {
                 show_code_change
             {
                 for part in parts {
-                    let snippet = if let Ok(snippet) = sm.span_to_snippet(part.span) {
-                        snippet
-                    } else {
-                        String::new()
-                    };
                     let span_start_pos = sm.lookup_char_pos(part.span.lo()).col_display;
                     let span_end_pos = sm.lookup_char_pos(part.span.hi()).col_display;
 
@@ -2402,7 +2397,7 @@ impl HumanEmitter {
                         // LL - REMOVED <- row_num - 2 - (newlines - first_i - 1)
                         // LL + NEWER
                         //    |         <- row_num
-
+                        let snippet = sm.span_to_snippet(part.span).unwrap_or_default();
                         let newlines = snippet.lines().count();
                         if newlines > 0 && row_num > newlines {
                             // Account for removals where the part being removed spans multiple
diff --git a/compiler/rustc_hir/src/attrs/data_structures.rs b/compiler/rustc_hir/src/attrs/data_structures.rs
index 7ddd71c346006..4ba64b240ac03 100644
--- a/compiler/rustc_hir/src/attrs/data_structures.rs
+++ b/compiler/rustc_hir/src/attrs/data_structures.rs
@@ -194,6 +194,18 @@ pub enum CfgEntry {
     Version(Option<RustcVersion>, Span),
 }
 
+impl CfgEntry {
+    pub fn span(&self) -> Span {
+        let (CfgEntry::All(_, span)
+        | CfgEntry::Any(_, span)
+        | CfgEntry::Not(_, span)
+        | CfgEntry::Bool(_, span)
+        | CfgEntry::NameValue { span, .. }
+        | CfgEntry::Version(_, span)) = self;
+        *span
+    }
+}
+
 /// Possible values for the `#[linkage]` attribute, allowing to specify the
 /// linkage type for a `MonoItem`.
 ///
diff --git a/compiler/rustc_hir_analysis/src/variance/terms.rs b/compiler/rustc_hir_analysis/src/variance/terms.rs
index cf38957bf24aa..9c7680b921205 100644
--- a/compiler/rustc_hir_analysis/src/variance/terms.rs
+++ b/compiler/rustc_hir_analysis/src/variance/terms.rs
@@ -44,7 +44,7 @@ impl<'a> fmt::Debug for VarianceTerm<'a> {
     }
 }
 
-/// The first pass over the crate simply builds up the set of inferreds.
+// The first pass over the crate simply builds up the set of inferreds.
 
 pub(crate) struct TermsContext<'a, 'tcx> {
     pub tcx: TyCtxt<'tcx>,
diff --git a/compiler/rustc_lint/src/passes.rs b/compiler/rustc_lint/src/passes.rs
index 191eb721b3477..ae145543e70dc 100644
--- a/compiler/rustc_lint/src/passes.rs
+++ b/compiler/rustc_lint/src/passes.rs
@@ -55,10 +55,10 @@ macro_rules! late_lint_methods {
 /// Each `check` method checks a single syntax node, and should not
 /// invoke methods recursively (unlike `Visitor`). By default they
 /// do nothing.
-//
+///
 // FIXME: eliminate the duplication with `Visitor`. But this also
 // contains a few lint-specific methods with no equivalent in `Visitor`.
-
+//
 macro_rules! declare_late_lint_pass {
     ([], [$($(#[$attr:meta])* fn $name:ident($($param:ident: $arg:ty),*);)*]) => (
         pub trait LateLintPass<'tcx>: LintPass {
diff --git a/compiler/rustc_metadata/src/native_libs.rs b/compiler/rustc_metadata/src/native_libs.rs
index 291f5c65dfa27..10fe23a0a65c9 100644
--- a/compiler/rustc_metadata/src/native_libs.rs
+++ b/compiler/rustc_metadata/src/native_libs.rs
@@ -67,7 +67,7 @@ pub fn walk_native_lib_search_dirs<R>(
     // FIXME: On AIX this also has the side-effect of making the list of library search paths
     // non-empty, which is needed or the linker may decide to record the LIBPATH env, if
     // defined, as the search path instead of appending the default search paths.
-    if sess.target.vendor == "fortanix"
+    if sess.target.abi == "fortanix"
         || sess.target.os == "linux"
         || sess.target.os == "fuchsia"
         || sess.target.is_like_aix
diff --git a/compiler/rustc_middle/src/mir/consts.rs b/compiler/rustc_middle/src/mir/consts.rs
index 5764a9c84eeaf..6985cc7ddcfa1 100644
--- a/compiler/rustc_middle/src/mir/consts.rs
+++ b/compiler/rustc_middle/src/mir/consts.rs
@@ -16,7 +16,7 @@ use crate::ty::{self, ConstKind, GenericArgsRef, ScalarInt, Ty, TyCtxt};
 
 ///////////////////////////////////////////////////////////////////////////
 /// Evaluated Constants
-
+///
 /// Represents the result of const evaluation via the `eval_to_allocation` query.
 /// Not to be confused with `ConstAllocation`, which directly refers to the underlying data!
 /// Here we indirect via an `AllocId`.
diff --git a/compiler/rustc_middle/src/ty/util.rs b/compiler/rustc_middle/src/ty/util.rs
index a4422abc6883a..782ea3906ef13 100644
--- a/compiler/rustc_middle/src/ty/util.rs
+++ b/compiler/rustc_middle/src/ty/util.rs
@@ -607,9 +607,9 @@ impl<'tcx> TyCtxt<'tcx> {
     /// have the same `DefKind`.
     ///
     /// Note that closures have a `DefId`, but the closure *expression* also has a
-    // `HirId` that is located within the context where the closure appears (and, sadly,
-    // a corresponding `NodeId`, since those are not yet phased out). The parent of
-    // the closure's `DefId` will also be the context where it appears.
+    /// `HirId` that is located within the context where the closure appears (and, sadly,
+    /// a corresponding `NodeId`, since those are not yet phased out). The parent of
+    /// the closure's `DefId` will also be the context where it appears.
     pub fn is_closure_like(self, def_id: DefId) -> bool {
         matches!(self.def_kind(def_id), DefKind::Closure)
     }
diff --git a/compiler/rustc_parse/src/parser/cfg_select.rs b/compiler/rustc_parse/src/parser/cfg_select.rs
index 08a71db4de853..9692d2c708938 100644
--- a/compiler/rustc_parse/src/parser/cfg_select.rs
+++ b/compiler/rustc_parse/src/parser/cfg_select.rs
@@ -1,83 +1,34 @@
-use rustc_ast::token::Token;
+use rustc_ast::token;
 use rustc_ast::tokenstream::{TokenStream, TokenTree};
 use rustc_ast::util::classify;
-use rustc_ast::{MetaItemInner, token};
 use rustc_errors::PResult;
-use rustc_span::Span;
 
 use crate::exp;
 use crate::parser::{AttrWrapper, ForceCollect, Parser, Restrictions, Trailing, UsePreAttrPos};
 
-pub enum CfgSelectPredicate {
-    Cfg(MetaItemInner),
-    Wildcard(Token),
-}
-
-#[derive(Default)]
-pub struct CfgSelectBranches {
-    /// All the conditional branches.
-    pub reachable: Vec<(MetaItemInner, TokenStream, Span)>,
-    /// The first wildcard `_ => { ... }` branch.
-    pub wildcard: Option<(Token, TokenStream, Span)>,
-    /// All branches after the first wildcard, including further wildcards.
-    /// These branches are kept for formatting.
-    pub unreachable: Vec<(CfgSelectPredicate, TokenStream, Span)>,
-}
-
-/// Parses a `TokenTree` consisting either of `{ /* ... */ }` (and strip the braces) or an
-/// expression followed by a comma (and strip the comma).
-fn parse_token_tree<'a>(p: &mut Parser<'a>) -> PResult<'a, TokenStream> {
-    if p.token == token::OpenBrace {
-        // Strip the outer '{' and '}'.
-        match p.parse_token_tree() {
-            TokenTree::Token(..) => unreachable!("because of the expect above"),
-            TokenTree::Delimited(.., tts) => return Ok(tts),
-        }
-    }
-    let expr = p.collect_tokens(None, AttrWrapper::empty(), ForceCollect::Yes, |p, _| {
-        p.parse_expr_res(Restrictions::STMT_EXPR, AttrWrapper::empty())
-            .map(|(expr, _)| (expr, Trailing::No, UsePreAttrPos::No))
-    })?;
-    if !classify::expr_is_complete(&expr) && p.token != token::CloseBrace && p.token != token::Eof {
-        p.expect(exp!(Comma))?;
-    } else {
-        let _ = p.eat(exp!(Comma));
-    }
-    Ok(TokenStream::from_ast(&expr))
-}
-
-pub fn parse_cfg_select<'a>(p: &mut Parser<'a>) -> PResult<'a, CfgSelectBranches> {
-    let mut branches = CfgSelectBranches::default();
-
-    while p.token != token::Eof {
-        if p.eat_keyword(exp!(Underscore)) {
-            let underscore = p.prev_token;
-            p.expect(exp!(FatArrow))?;
-
-            let tts = parse_token_tree(p)?;
-            let span = underscore.span.to(p.token.span);
-
-            match branches.wildcard {
-                None => branches.wildcard = Some((underscore, tts, span)),
-                Some(_) => {
-                    branches.unreachable.push((CfgSelectPredicate::Wildcard(underscore), tts, span))
-                }
+impl<'a> Parser<'a> {
+    /// Parses a `TokenTree` consisting either of `{ /* ... */ }` (and strip the braces) or an
+    /// expression followed by a comma (and strip the comma).
+    pub fn parse_delimited_token_tree(&mut self) -> PResult<'a, TokenStream> {
+        if self.token == token::OpenBrace {
+            // Strip the outer '{' and '}'.
+            match self.parse_token_tree() {
+                TokenTree::Token(..) => unreachable!("because of the expect above"),
+                TokenTree::Delimited(.., tts) => return Ok(tts),
             }
+        }
+        let expr = self.collect_tokens(None, AttrWrapper::empty(), ForceCollect::Yes, |p, _| {
+            p.parse_expr_res(Restrictions::STMT_EXPR, AttrWrapper::empty())
+                .map(|(expr, _)| (expr, Trailing::No, UsePreAttrPos::No))
+        })?;
+        if !classify::expr_is_complete(&expr)
+            && self.token != token::CloseBrace
+            && self.token != token::Eof
+        {
+            self.expect(exp!(Comma))?;
         } else {
-            let meta_item = p.parse_meta_item_inner()?;
-            p.expect(exp!(FatArrow))?;
-
-            let tts = parse_token_tree(p)?;
-            let span = meta_item.span().to(p.token.span);
-
-            match branches.wildcard {
-                None => branches.reachable.push((meta_item, tts, span)),
-                Some(_) => {
-                    branches.unreachable.push((CfgSelectPredicate::Cfg(meta_item), tts, span))
-                }
-            }
+            let _ = self.eat(exp!(Comma));
         }
+        Ok(TokenStream::from_ast(&expr))
     }
-
-    Ok(branches)
 }
diff --git a/compiler/rustc_session/src/config/cfg.rs b/compiler/rustc_session/src/config/cfg.rs
index 26ff87417ab0d..50c88e8b1e62a 100644
--- a/compiler/rustc_session/src/config/cfg.rs
+++ b/compiler/rustc_session/src/config/cfg.rs
@@ -298,7 +298,7 @@ pub(crate) fn default_configuration(sess: &Session) -> Cfg {
         ins_none!(sym::target_thread_local);
     }
 
-    ins_str!(sym::target_vendor, &sess.target.vendor);
+    ins_sym!(sym::target_vendor, sess.target.vendor_symbol());
 
     // If the user wants a test runner, then add the test cfg.
     if sess.is_test_crate() {
@@ -456,7 +456,7 @@ impl CheckCfg {
                     );
                     values_target_os.insert(Symbol::intern(&target.options.os));
                     values_target_pointer_width.insert(sym::integer(target.pointer_width));
-                    values_target_vendor.insert(Symbol::intern(&target.options.vendor));
+                    values_target_vendor.insert(target.vendor_symbol());
                 }
             }
         }
diff --git a/compiler/rustc_target/src/lib.rs b/compiler/rustc_target/src/lib.rs
index 2d83caa07676a..73a0d9eea7326 100644
--- a/compiler/rustc_target/src/lib.rs
+++ b/compiler/rustc_target/src/lib.rs
@@ -9,7 +9,9 @@
 
 // tidy-alphabetical-start
 #![cfg_attr(bootstrap, feature(debug_closure_helpers))]
+#![expect(internal_features)]
 #![feature(iter_intersperse)]
+#![feature(rustc_attrs)]
 // tidy-alphabetical-end
 
 use std::path::{Path, PathBuf};
diff --git a/compiler/rustc_target/src/spec/base/windows_uwp_msvc.rs b/compiler/rustc_target/src/spec/base/windows_uwp_msvc.rs
index 374918d38a791..4f9d9c83761f4 100644
--- a/compiler/rustc_target/src/spec/base/windows_uwp_msvc.rs
+++ b/compiler/rustc_target/src/spec/base/windows_uwp_msvc.rs
@@ -1,10 +1,9 @@
 use crate::spec::{LinkerFlavor, Lld, TargetOptions, base};
 
 pub(crate) fn opts() -> TargetOptions {
-    let mut opts = base::windows_msvc::opts();
+    let mut opts =
+        TargetOptions { abi: "uwp".into(), vendor: "uwp".into(), ..base::windows_msvc::opts() };
 
-    opts.abi = "uwp".into();
-    opts.vendor = "uwp".into();
     opts.add_pre_link_args(LinkerFlavor::Msvc(Lld::No), &["/APPCONTAINER", "mincore.lib"]);
 
     opts
diff --git a/compiler/rustc_target/src/spec/json.rs b/compiler/rustc_target/src/spec/json.rs
index ab2879f6c6ea8..8ac09205fbc89 100644
--- a/compiler/rustc_target/src/spec/json.rs
+++ b/compiler/rustc_target/src/spec/json.rs
@@ -261,6 +261,7 @@ impl ToJson for Target {
             ($attr:ident) => {{ target_option_val!($attr, (stringify!($attr)).replace("_", "-")) }};
             ($attr:ident, $json_name:expr) => {{
                 let name = $json_name;
+                #[allow(rustc::bad_opt_access)]
                 if default.$attr != target.$attr {
                     d.insert(name.into(), target.$attr.to_json());
                 }
diff --git a/compiler/rustc_target/src/spec/mod.rs b/compiler/rustc_target/src/spec/mod.rs
index 2dd0fbc4517a5..08fae288c441c 100644
--- a/compiler/rustc_target/src/spec/mod.rs
+++ b/compiler/rustc_target/src/spec/mod.rs
@@ -2045,6 +2045,7 @@ type StaticCow<T> = Cow<'static, T>;
 /// construction, all its fields logically belong to `Target` and available from `Target`
 /// through `Deref` impls.
 #[derive(PartialEq, Clone, Debug)]
+#[rustc_lint_opt_ty]
 pub struct TargetOptions {
     /// Used as the `target_endian` `cfg` variable. Defaults to little endian.
     pub endian: Endian,
@@ -2063,7 +2064,10 @@ pub struct TargetOptions {
     /// However, parts of the backend do check this field for specific values to enable special behavior.
     pub abi: StaticCow<str>,
     /// Vendor name to use for conditional compilation (`target_vendor`). Defaults to "unknown".
-    pub vendor: StaticCow<str>,
+    #[rustc_lint_opt_deny_field_access(
+        "use `Target::is_like_*` instead of this field; see https://github.com/rust-lang/rust/issues/100343 for rationale"
+    )]
+    vendor: StaticCow<str>,
 
     /// Linker to invoke
     pub linker: Option<StaticCow<str>>,
@@ -3323,6 +3327,10 @@ impl Target {
             Align::MAX
         }
     }
+
+    pub fn vendor_symbol(&self) -> Symbol {
+        Symbol::intern(&self.vendor)
+    }
 }
 
 /// Either a target tuple string or a path to a JSON file.
diff --git a/compiler/rustc_target/src/spec/targets/armv6k_nintendo_3ds.rs b/compiler/rustc_target/src/spec/targets/armv6k_nintendo_3ds.rs
index a79c642870126..37a8b1d878098 100644
--- a/compiler/rustc_target/src/spec/targets/armv6k_nintendo_3ds.rs
+++ b/compiler/rustc_target/src/spec/targets/armv6k_nintendo_3ds.rs
@@ -5,7 +5,6 @@ use crate::spec::{
 /// A base target for Nintendo 3DS devices using the devkitARM toolchain.
 ///
 /// Requires the devkitARM toolchain for 3DS targets on the host system.
-
 pub(crate) fn target() -> Target {
     let pre_link_args = TargetOptions::link_args(
         LinkerFlavor::Gnu(Cc::Yes, Lld::No),
diff --git a/compiler/rustc_target/src/spec/targets/armv7_sony_vita_newlibeabihf.rs b/compiler/rustc_target/src/spec/targets/armv7_sony_vita_newlibeabihf.rs
index 6c02ec26fea48..631b9770fac54 100644
--- a/compiler/rustc_target/src/spec/targets/armv7_sony_vita_newlibeabihf.rs
+++ b/compiler/rustc_target/src/spec/targets/armv7_sony_vita_newlibeabihf.rs
@@ -7,7 +7,6 @@ use crate::spec::{
 /// A base target for PlayStation Vita devices using the VITASDK toolchain (using newlib).
 ///
 /// Requires the VITASDK toolchain on the host system.
-
 pub(crate) fn target() -> Target {
     let pre_link_args = TargetOptions::link_args(
         LinkerFlavor::Gnu(Cc::Yes, Lld::No),
diff --git a/compiler/rustc_target/src/spec/targets/i686_win7_windows_gnu.rs b/compiler/rustc_target/src/spec/targets/i686_win7_windows_gnu.rs
index c026f915906cb..43ebc54c2b402 100644
--- a/compiler/rustc_target/src/spec/targets/i686_win7_windows_gnu.rs
+++ b/compiler/rustc_target/src/spec/targets/i686_win7_windows_gnu.rs
@@ -1,15 +1,18 @@
 use crate::spec::{
-    Arch, Cc, FramePointer, LinkerFlavor, Lld, RustcAbi, Target, TargetMetadata, base,
+    Arch, Cc, FramePointer, LinkerFlavor, Lld, RustcAbi, Target, TargetMetadata, TargetOptions,
+    base,
 };
 
 pub(crate) fn target() -> Target {
-    let mut base = base::windows_gnu::opts();
-    base.vendor = "win7".into();
-    base.rustc_abi = Some(RustcAbi::X86Sse2);
-    base.cpu = "pentium4".into();
-    base.max_atomic_width = Some(64);
-    base.frame_pointer = FramePointer::Always; // Required for backtraces
-    base.linker = Some("i686-w64-mingw32-gcc".into());
+    let mut base = TargetOptions {
+        vendor: "win7".into(),
+        rustc_abi: Some(RustcAbi::X86Sse2),
+        cpu: "pentium4".into(),
+        max_atomic_width: Some(64),
+        frame_pointer: FramePointer::Always, // Required for backtraces
+        linker: Some("i686-w64-mingw32-gcc".into()),
+        ..base::windows_gnu::opts()
+    };
 
     // Mark all dynamic libraries and executables as compatible with the larger 4GiB address
     // space available to x86 Windows binaries on x86_64.
diff --git a/compiler/rustc_target/src/spec/targets/i686_win7_windows_msvc.rs b/compiler/rustc_target/src/spec/targets/i686_win7_windows_msvc.rs
index 68131bf654264..8994c245d7b90 100644
--- a/compiler/rustc_target/src/spec/targets/i686_win7_windows_msvc.rs
+++ b/compiler/rustc_target/src/spec/targets/i686_win7_windows_msvc.rs
@@ -1,18 +1,22 @@
-use crate::spec::{Arch, LinkerFlavor, Lld, RustcAbi, SanitizerSet, Target, TargetMetadata, base};
+use crate::spec::{
+    Arch, LinkerFlavor, Lld, RustcAbi, SanitizerSet, Target, TargetMetadata, TargetOptions, base,
+};
 
 pub(crate) fn target() -> Target {
-    let mut base = base::windows_msvc::opts();
-    base.vendor = "win7".into();
-    base.rustc_abi = Some(RustcAbi::X86Sse2);
-    base.cpu = "pentium4".into();
-    base.max_atomic_width = Some(64);
-    base.supported_sanitizers = SanitizerSet::ADDRESS;
-    // On Windows 7 32-bit, the alignment characteristic of the TLS Directory
-    // don't appear to be respected by the PE Loader, leading to crashes. As
-    // a result, let's disable has_thread_local to make sure TLS goes through
-    // the emulation layer.
-    // See https://github.com/rust-lang/rust/issues/138903
-    base.has_thread_local = false;
+    let mut base = TargetOptions {
+        vendor: "win7".into(),
+        rustc_abi: Some(RustcAbi::X86Sse2),
+        cpu: "pentium4".into(),
+        max_atomic_width: Some(64),
+        supported_sanitizers: SanitizerSet::ADDRESS,
+        // On Windows 7 32-bit, the alignment characteristic of the TLS Directory
+        // don't appear to be respected by the PE Loader, leading to crashes. As
+        // a result, let's disable has_thread_local to make sure TLS goes through
+        // the emulation layer.
+        // See https://github.com/rust-lang/rust/issues/138903
+        has_thread_local: false,
+        ..base::windows_msvc::opts()
+    };
 
     base.add_pre_link_args(
         LinkerFlavor::Msvc(Lld::No),
diff --git a/compiler/rustc_target/src/spec/targets/sparcv9_sun_solaris.rs b/compiler/rustc_target/src/spec/targets/sparcv9_sun_solaris.rs
index 79035c791156d..498d8182ad589 100644
--- a/compiler/rustc_target/src/spec/targets/sparcv9_sun_solaris.rs
+++ b/compiler/rustc_target/src/spec/targets/sparcv9_sun_solaris.rs
@@ -1,15 +1,17 @@
 use rustc_abi::Endian;
 
-use crate::spec::{Arch, Cc, LinkerFlavor, Target, TargetMetadata, base};
+use crate::spec::{Arch, Cc, LinkerFlavor, Target, TargetMetadata, TargetOptions, base};
 
 pub(crate) fn target() -> Target {
-    let mut base = base::solaris::opts();
-    base.endian = Endian::Big;
+    let mut base = TargetOptions {
+        endian: Endian::Big,
+        // llvm calls this "v9"
+        cpu: "v9".into(),
+        vendor: "sun".into(),
+        max_atomic_width: Some(64),
+        ..base::solaris::opts()
+    };
     base.add_pre_link_args(LinkerFlavor::Unix(Cc::Yes), &["-m64"]);
-    // llvm calls this "v9"
-    base.cpu = "v9".into();
-    base.vendor = "sun".into();
-    base.max_atomic_width = Some(64);
 
     Target {
         llvm_target: "sparcv9-sun-solaris".into(),
diff --git a/compiler/rustc_target/src/spec/targets/x86_64_pc_solaris.rs b/compiler/rustc_target/src/spec/targets/x86_64_pc_solaris.rs
index 7b8d5def3a70b..39ebe62430479 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64_pc_solaris.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64_pc_solaris.rs
@@ -1,16 +1,19 @@
 use crate::spec::{
-    Arch, Cc, LinkerFlavor, SanitizerSet, StackProbeType, Target, TargetMetadata, base,
+    Arch, Cc, LinkerFlavor, SanitizerSet, StackProbeType, Target, TargetMetadata, TargetOptions,
+    base,
 };
 
 pub(crate) fn target() -> Target {
-    let mut base = base::solaris::opts();
+    let mut base = TargetOptions {
+        cpu: "x86-64".into(),
+        plt_by_default: false,
+        vendor: "pc".into(),
+        max_atomic_width: Some(64),
+        stack_probes: StackProbeType::Inline,
+        supported_sanitizers: SanitizerSet::ADDRESS | SanitizerSet::CFI | SanitizerSet::THREAD,
+        ..base::solaris::opts()
+    };
     base.add_pre_link_args(LinkerFlavor::Unix(Cc::Yes), &["-m64"]);
-    base.cpu = "x86-64".into();
-    base.plt_by_default = false;
-    base.vendor = "pc".into();
-    base.max_atomic_width = Some(64);
-    base.stack_probes = StackProbeType::Inline;
-    base.supported_sanitizers = SanitizerSet::ADDRESS | SanitizerSet::CFI | SanitizerSet::THREAD;
 
     Target {
         llvm_target: "x86_64-pc-solaris".into(),
diff --git a/compiler/rustc_target/src/spec/targets/x86_64_win7_windows_gnu.rs b/compiler/rustc_target/src/spec/targets/x86_64_win7_windows_gnu.rs
index 22a1a126b8912..0bd4215855264 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64_win7_windows_gnu.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64_win7_windows_gnu.rs
@@ -1,18 +1,20 @@
-use crate::spec::{Arch, Cc, LinkerFlavor, Lld, Target, TargetMetadata, base};
+use crate::spec::{Arch, Cc, LinkerFlavor, Lld, Target, TargetMetadata, TargetOptions, base};
 
 pub(crate) fn target() -> Target {
-    let mut base = base::windows_gnu::opts();
-    base.vendor = "win7".into();
-    base.cpu = "x86-64".into();
-    base.plt_by_default = false;
+    let mut base = TargetOptions {
+        vendor: "win7".into(),
+        cpu: "x86-64".into(),
+        plt_by_default: false,
+        max_atomic_width: Some(64),
+        linker: Some("x86_64-w64-mingw32-gcc".into()),
+        ..base::windows_gnu::opts()
+    };
     // Use high-entropy 64 bit address space for ASLR
     base.add_pre_link_args(
         LinkerFlavor::Gnu(Cc::No, Lld::No),
         &["-m", "i386pep", "--high-entropy-va"],
     );
     base.add_pre_link_args(LinkerFlavor::Gnu(Cc::Yes, Lld::No), &["-m64", "-Wl,--high-entropy-va"]);
-    base.max_atomic_width = Some(64);
-    base.linker = Some("x86_64-w64-mingw32-gcc".into());
 
     Target {
         llvm_target: "x86_64-pc-windows-gnu".into(),
diff --git a/compiler/rustc_target/src/spec/targets/x86_64_win7_windows_msvc.rs b/compiler/rustc_target/src/spec/targets/x86_64_win7_windows_msvc.rs
index 99b59154811f2..1cc2efaae5f5f 100644
--- a/compiler/rustc_target/src/spec/targets/x86_64_win7_windows_msvc.rs
+++ b/compiler/rustc_target/src/spec/targets/x86_64_win7_windows_msvc.rs
@@ -1,12 +1,14 @@
-use crate::spec::{Arch, SanitizerSet, Target, TargetMetadata, base};
+use crate::spec::{Arch, SanitizerSet, Target, TargetMetadata, TargetOptions, base};
 
 pub(crate) fn target() -> Target {
-    let mut base = base::windows_msvc::opts();
-    base.vendor = "win7".into();
-    base.cpu = "x86-64".into();
-    base.plt_by_default = false;
-    base.max_atomic_width = Some(64);
-    base.supported_sanitizers = SanitizerSet::ADDRESS;
+    let base = TargetOptions {
+        vendor: "win7".into(),
+        cpu: "x86-64".into(),
+        plt_by_default: false,
+        max_atomic_width: Some(64),
+        supported_sanitizers: SanitizerSet::ADDRESS,
+        ..base::windows_msvc::opts()
+    };
 
     Target {
         llvm_target: "x86_64-pc-windows-msvc".into(),
diff --git a/library/core/src/num/int_macros.rs b/library/core/src/num/int_macros.rs
index 7d395eb780346..9e3aeed69572f 100644
--- a/library/core/src/num/int_macros.rs
+++ b/library/core/src/num/int_macros.rs
@@ -1503,7 +1503,7 @@ macro_rules! int_impl {
             }
         }
 
-        /// Strict shift right. Computes `self >> rhs`, panicking `rhs` is
+        /// Strict shift right. Computes `self >> rhs`, panicking if `rhs` is
         /// larger than or equal to the number of bits in `self`.
         ///
         /// # Panics
diff --git a/library/core/src/num/uint_macros.rs b/library/core/src/num/uint_macros.rs
index 2996e7b00da4e..8b3b122998774 100644
--- a/library/core/src/num/uint_macros.rs
+++ b/library/core/src/num/uint_macros.rs
@@ -1900,7 +1900,7 @@ macro_rules! uint_impl {
             }
         }
 
-        /// Strict shift right. Computes `self >> rhs`, panicking `rhs` is
+        /// Strict shift right. Computes `self >> rhs`, panicking if `rhs` is
         /// larger than or equal to the number of bits in `self`.
         ///
         /// # Panics
diff --git a/src/librustdoc/passes/collect_intra_doc_links.rs b/src/librustdoc/passes/collect_intra_doc_links.rs
index d09949e6868d6..8af197212f8bd 100644
--- a/src/librustdoc/passes/collect_intra_doc_links.rs
+++ b/src/librustdoc/passes/collect_intra_doc_links.rs
@@ -1215,7 +1215,6 @@ impl LinkCollector<'_, '_> {
             || !did.is_local()
     }
 
-    #[allow(rustc::potential_query_instability)]
     pub(crate) fn resolve_ambiguities(&mut self) {
         let mut ambiguous_links = mem::take(&mut self.ambiguous_links);
         for ((item_id, path_str), info_items) in ambiguous_links.iter_mut() {
diff --git a/src/tools/miri/src/machine.rs b/src/tools/miri/src/machine.rs
index 304ae00b01a92..a4f8e9ccaab99 100644
--- a/src/tools/miri/src/machine.rs
+++ b/src/tools/miri/src/machine.rs
@@ -715,7 +715,7 @@ impl<'tcx> MiriMachine<'tcx> {
             match target.arch {
                 Arch::Wasm32 | Arch::Wasm64 => 64 * 1024, // https://webassembly.github.io/spec/core/exec/runtime.html#memory-instances
                 Arch::AArch64 => {
-                    if target.options.vendor.as_ref() == "apple" {
+                    if target.is_like_darwin {
                         // No "definitive" source, but see:
                         // https://www.wwdcnotes.com/notes/wwdc20/10214/
                         // https://github.com/ziglang/zig/issues/11308 etc.
diff --git a/tests/run-make/rustdoc-test-builder/builder.rs b/tests/run-make/rustdoc-test-builder/builder.rs
new file mode 100644
index 0000000000000..b5a2c8ae346ea
--- /dev/null
+++ b/tests/run-make/rustdoc-test-builder/builder.rs
@@ -0,0 +1,23 @@
+use std::ffi::OsString;
+use std::path::PathBuf;
+use std::process::{self, Command};
+use std::{env, fs};
+
+fn main() {
+    let args: Vec<OsString> = env::args_os().collect();
+    let log_path = env::var_os("BUILDER_LOG").map(PathBuf::from).expect("BUILDER_LOG must be set");
+    let real_rustc = env::var_os("REAL_RUSTC").expect("REAL_RUSTC must be set");
+
+    let log_contents =
+        args.iter().skip(1).map(|arg| arg.to_string_lossy()).collect::<Vec<_>>().join("\n");
+    fs::write(&log_path, log_contents).expect("failed to write builder log");
+
+    let status = Command::new(real_rustc)
+        .args(args.iter().skip(1))
+        .status()
+        .expect("failed to invoke real rustc");
+
+    if !status.success() {
+        process::exit(status.code().unwrap_or(1));
+    }
+}
diff --git a/tests/run-make/rustdoc-test-builder/doctest.rs b/tests/run-make/rustdoc-test-builder/doctest.rs
new file mode 100644
index 0000000000000..1a4ff6a2fdd76
--- /dev/null
+++ b/tests/run-make/rustdoc-test-builder/doctest.rs
@@ -0,0 +1,3 @@
+//! ```rust
+//! assert_eq!(2 + 2, 4);
+//! ```
diff --git a/tests/run-make/rustdoc-test-builder/rmake.rs b/tests/run-make/rustdoc-test-builder/rmake.rs
index 9aa8143dc1dc4..d10a3c92cae42 100644
--- a/tests/run-make/rustdoc-test-builder/rmake.rs
+++ b/tests/run-make/rustdoc-test-builder/rmake.rs
@@ -1,11 +1,14 @@
-// This test ensures that if the rustdoc test binary is not executable, it will
-// gracefully fail and not panic.
+// This test validates the `--test-builder` rustdoc option.
+// It ensures that:
+// 1. When the test-builder path points to a non-executable file, rustdoc gracefully fails
+// 2. When the test-builder path points to a valid executable, it receives rustc arguments
 
 //@ needs-target-std
 
-use run_make_support::{path, rfs, rustdoc};
+use run_make_support::{bare_rustc, path, rfs, rustc_path, rustdoc, target};
 
 fn main() {
+    // Test 1: Verify that a non-executable test-builder fails gracefully
     let absolute_path = path("foo.rs").canonicalize().expect("failed to get absolute path");
     let output = rustdoc()
         .input("foo.rs")
@@ -19,4 +22,37 @@ fn main() {
     output.assert_stdout_contains("Failed to spawn ");
     // ... and that we didn't panic.
     output.assert_not_ice();
+
+    // Some targets (for example wasm) cannot execute doctests directly even with a runner,
+    // so only exercise the success path when the target can run on the host.
+    if target().contains("wasm") || std::env::var_os("REMOTE_TEST_CLIENT").is_some() {
+        return;
+    }
+
+    // Test 2: Verify that a valid test-builder is invoked with correct arguments
+    // Build a custom test-builder that logs its arguments and forwards to rustc.
+    // Use `bare_rustc` so we compile for the host architecture even in cross builds.
+    let builder_bin = path("builder-bin");
+    bare_rustc().input("builder.rs").output(&builder_bin).run();
+
+    let log_path = path("builder.log");
+    let _ = std::fs::remove_file(&log_path);
+
+    // Run rustdoc with our custom test-builder
+    rustdoc()
+        .input("doctest.rs")
+        .arg("--test")
+        .arg("-Zunstable-options")
+        .arg("--test-builder")
+        .arg(&builder_bin)
+        .env("REAL_RUSTC", rustc_path())
+        .env("BUILDER_LOG", &log_path)
+        .run();
+
+    // Verify the custom builder was invoked with rustc-style arguments
+    let log_contents = rfs::read_to_string(&log_path);
+    assert!(
+        log_contents.contains("--crate-type"),
+        "expected builder to receive rustc arguments, got:\n{log_contents}"
+    );
 }
diff --git a/tests/ui/macros/cfg_select.rs b/tests/ui/macros/cfg_select.rs
index 9241141ef9a6c..2a627cc05b93b 100644
--- a/tests/ui/macros/cfg_select.rs
+++ b/tests/ui/macros/cfg_select.rs
@@ -60,3 +60,38 @@ cfg_select! {
 
 cfg_select! {}
 //~^ ERROR none of the predicates in this `cfg_select` evaluated to true
+
+cfg_select! {
+    => {}
+    //~^ ERROR expected a literal (`1u8`, `1.0f32`, `"string"`, etc.) here, found `=>`
+}
+
+cfg_select! {
+    () => {}
+    //~^ ERROR expected a literal (`1u8`, `1.0f32`, `"string"`, etc.) here, found `(`
+}
+
+cfg_select! {
+    "str" => {}
+    //~^ ERROR malformed `cfg_select` macro input [E0539]
+}
+
+cfg_select! {
+    a::b => {}
+    //~^ ERROR malformed `cfg_select` macro input [E0539]
+}
+
+cfg_select! {
+    a() => {}
+    //~^ ERROR invalid predicate `a` [E0537]
+}
+
+cfg_select! {
+    a + 1 => {}
+    //~^ ERROR expected one of `(`, `::`, `=>`, or `=`, found `+`
+}
+
+cfg_select! {
+    cfg!() => {}
+    //~^ ERROR expected one of `(`, `::`, `=>`, or `=`, found `!`
+}
diff --git a/tests/ui/macros/cfg_select.stderr b/tests/ui/macros/cfg_select.stderr
index 7280f35c16f93..3a5d2b0a1e1ee 100644
--- a/tests/ui/macros/cfg_select.stderr
+++ b/tests/ui/macros/cfg_select.stderr
@@ -21,5 +21,51 @@ error: none of the predicates in this `cfg_select` evaluated to true
 LL | cfg_select! {}
    | ^^^^^^^^^^^^^^
 
-error: aborting due to 2 previous errors; 1 warning emitted
+error: expected a literal (`1u8`, `1.0f32`, `"string"`, etc.) here, found `=>`
+  --> $DIR/cfg_select.rs:65:5
+   |
+LL |     => {}
+   |     ^^
+
+error: expected a literal (`1u8`, `1.0f32`, `"string"`, etc.) here, found `(`
+  --> $DIR/cfg_select.rs:70:5
+   |
+LL |     () => {}
+   |     ^
+
+error[E0539]: malformed `cfg_select` macro input
+  --> $DIR/cfg_select.rs:75:5
+   |
+LL |     "str" => {}
+   |     ^^^^^ expected a valid identifier here
+   |
+
+error[E0539]: malformed `cfg_select` macro input
+  --> $DIR/cfg_select.rs:80:5
+   |
+LL |     a::b => {}
+   |     ^^^^ expected a valid identifier here
+   |
+
+error[E0537]: invalid predicate `a`
+  --> $DIR/cfg_select.rs:85:5
+   |
+LL |     a() => {}
+   |     ^^^
+
+error: expected one of `(`, `::`, `=>`, or `=`, found `+`
+  --> $DIR/cfg_select.rs:90:7
+   |
+LL |     a + 1 => {}
+   |       ^ expected one of `(`, `::`, `=>`, or `=`
+
+error: expected one of `(`, `::`, `=>`, or `=`, found `!`
+  --> $DIR/cfg_select.rs:95:8
+   |
+LL |     cfg!() => {}
+   |        ^ expected one of `(`, `::`, `=>`, or `=`
+
+error: aborting due to 9 previous errors; 1 warning emitted
 
+Some errors have detailed explanations: E0537, E0539.
+For more information about an error, try `rustc --explain E0537`.