Auto merge of #124360 - matthiaskrgr:rollup-k6bffhd, r=matthiaskrgr

Rollup of 3 pull requests

Successful merges:

 - #124257 (Rewrite the `no-input-file.stderr` test in Rust and support diff)
 - #124324 (Minor AST cleanups)
 - #124327 (CI: implement job skipping in Python matrix calculation)

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

21 files changed, 256 insertions, 193 deletions

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 872b671b031..3651ef2c614 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -88,82 +88,57 @@ jobs:
         run: "echo \"[CI_PR_NUMBER=$num]\""
         env:
           num: "${{ github.event.number }}"
-        if: "success() && !env.SKIP_JOB && github.event_name == 'pull_request'"
+        if: "success() && github.event_name == 'pull_request'"
       - name: add extra environment variables
         run: src/ci/scripts/setup-environment.sh
         env:
           EXTRA_VARIABLES: "${{ toJson(matrix.env) }}"
-        if: success() && !env.SKIP_JOB
-      - name: decide whether to skip this job
-        run: src/ci/scripts/should-skip-this.sh
-        if: success() && !env.SKIP_JOB
       - name: ensure the channel matches the target branch
         run: src/ci/scripts/verify-channel.sh
-        if: success() && !env.SKIP_JOB
       - name: collect CPU statistics
         run: src/ci/scripts/collect-cpu-stats.sh
-        if: success() && !env.SKIP_JOB
       - name: show the current environment
         run: src/ci/scripts/dump-environment.sh
-        if: success() && !env.SKIP_JOB
       - name: install awscli
         run: src/ci/scripts/install-awscli.sh
-        if: success() && !env.SKIP_JOB
       - name: install sccache
         run: src/ci/scripts/install-sccache.sh
-        if: success() && !env.SKIP_JOB
       - name: select Xcode
         run: src/ci/scripts/select-xcode.sh
-        if: success() && !env.SKIP_JOB
       - name: install clang
         run: src/ci/scripts/install-clang.sh
-        if: success() && !env.SKIP_JOB
       - name: install tidy
         run: src/ci/scripts/install-tidy.sh
-        if: success() && !env.SKIP_JOB
       - name: install WIX
         run: src/ci/scripts/install-wix.sh
-        if: success() && !env.SKIP_JOB
       - name: disable git crlf conversion
         run: src/ci/scripts/disable-git-crlf-conversion.sh
-        if: success() && !env.SKIP_JOB
       - name: checkout submodules
         run: src/ci/scripts/checkout-submodules.sh
-        if: success() && !env.SKIP_JOB
       - name: install MSYS2
         run: src/ci/scripts/install-msys2.sh
-        if: success() && !env.SKIP_JOB
       - name: install MinGW
         run: src/ci/scripts/install-mingw.sh
-        if: success() && !env.SKIP_JOB
       - name: install ninja
         run: src/ci/scripts/install-ninja.sh
-        if: success() && !env.SKIP_JOB
       - name: enable ipv6 on Docker
         run: src/ci/scripts/enable-docker-ipv6.sh
-        if: success() && !env.SKIP_JOB
       - name: disable git crlf conversion
         run: src/ci/scripts/disable-git-crlf-conversion.sh
-        if: success() && !env.SKIP_JOB
       - name: ensure line endings are correct
         run: src/ci/scripts/verify-line-endings.sh
-        if: success() && !env.SKIP_JOB
       - name: ensure backported commits are in upstream branches
         run: src/ci/scripts/verify-backported-commits.sh
-        if: success() && !env.SKIP_JOB
       - name: ensure the stable version number is correct
         run: src/ci/scripts/verify-stable-version-number.sh
-        if: success() && !env.SKIP_JOB
       - name: run the build
         run: src/ci/scripts/run-build-from-ci.sh 2>&1
         env:
           AWS_ACCESS_KEY_ID: "${{ env.CACHES_AWS_ACCESS_KEY_ID }}"
           AWS_SECRET_ACCESS_KEY: "${{ secrets[format('AWS_SECRET_ACCESS_KEY_{0}', env.CACHES_AWS_ACCESS_KEY_ID)] }}"
           TOOLSTATE_REPO_ACCESS_TOKEN: "${{ secrets.TOOLSTATE_REPO_ACCESS_TOKEN }}"
-        if: success() && !env.SKIP_JOB
       - name: create github artifacts
         run: src/ci/scripts/create-doc-artifacts.sh
-        if: success() && !env.SKIP_JOB
       - name: upload artifacts to github
         uses: actions/upload-artifact@v4
         with:
@@ -171,13 +146,12 @@ jobs:
           path: obj/artifacts/doc
           if-no-files-found: ignore
           retention-days: 5
-        if: success() && !env.SKIP_JOB
       - name: upload artifacts to S3
         run: src/ci/scripts/upload-artifacts.sh
         env:
           AWS_ACCESS_KEY_ID: "${{ env.ARTIFACTS_AWS_ACCESS_KEY_ID }}"
           AWS_SECRET_ACCESS_KEY: "${{ secrets[format('AWS_SECRET_ACCESS_KEY_{0}', env.ARTIFACTS_AWS_ACCESS_KEY_ID)] }}"
-        if: "success() && !env.SKIP_JOB && (github.event_name == 'push' || env.DEPLOY == '1' || env.DEPLOY_ALT == '1')"
+        if: "success() && (github.event_name == 'push' || env.DEPLOY == '1' || env.DEPLOY_ALT == '1')"
   master:
     name: master
     runs-on: ubuntu-latest
@@ -202,7 +176,6 @@ jobs:
         shell: bash
         env:
           TOOLSTATE_REPO_ACCESS_TOKEN: "${{ secrets.TOOLSTATE_REPO_ACCESS_TOKEN }}"
-        if: success() && !env.SKIP_JOB
   try-success:
     needs:
       - job
diff --git a/Cargo.lock b/Cargo.lock
index 552b446a1e7..8a9701acae1 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -3343,6 +3343,7 @@ version = "0.0.0"
 dependencies = [
  "object 0.34.0",
  "regex",
+ "similar",
  "wasmparser",
 ]
 
@@ -5139,6 +5140,12 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0fda2ff0d084019ba4d7c6f371c95d8fd75ce3524c3cb8fb653a3023f6323e64"
 
 [[package]]
+name = "similar"
+version = "2.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fa42c91313f1d05da9b26f267f931cf178d4aba455b4c4622dd7355eb80c6640"
+
+[[package]]
 name = "siphasher"
 version = "0.3.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
diff --git a/compiler/rustc_ast/src/ast.rs b/compiler/rustc_ast/src/ast.rs
index 727c6bc82fe..af246e31371 100644
--- a/compiler/rustc_ast/src/ast.rs
+++ b/compiler/rustc_ast/src/ast.rs
@@ -2786,6 +2786,7 @@ pub enum AttrKind {
 #[derive(Clone, Encodable, Decodable, Debug)]
 pub struct NormalAttr {
     pub item: AttrItem,
+    // Tokens for the full attribute, e.g. `#[foo]`, `#![bar]`.
     pub tokens: Option<LazyAttrTokenStream>,
 }
 
@@ -2802,6 +2803,7 @@ impl NormalAttr {
 pub struct AttrItem {
     pub path: Path,
     pub args: AttrArgs,
+    // Tokens for the meta item, e.g. just the `foo` within `#[foo]` or `#![foo]`.
     pub tokens: Option<LazyAttrTokenStream>,
 }
 
diff --git a/compiler/rustc_ast/src/attr/mod.rs b/compiler/rustc_ast/src/attr/mod.rs
index 5e3fc7e3357..0f12fd31975 100644
--- a/compiler/rustc_ast/src/attr/mod.rs
+++ b/compiler/rustc_ast/src/attr/mod.rs
@@ -298,7 +298,10 @@ impl MetaItem {
     }
 
     pub fn value_str(&self) -> Option<Symbol> {
-        self.kind.value_str()
+        match &self.kind {
+            MetaItemKind::NameValue(v) => v.kind.str(),
+            _ => None,
+        }
     }
 
     fn from_tokens<'a, I>(tokens: &mut iter::Peekable<I>) -> Option<MetaItem>
@@ -362,13 +365,6 @@ impl MetaItem {
 }
 
 impl MetaItemKind {
-    pub fn value_str(&self) -> Option<Symbol> {
-        match self {
-            MetaItemKind::NameValue(v) => v.kind.str(),
-            _ => None,
-        }
-    }
-
     fn list_from_tokens(tokens: TokenStream) -> Option<ThinVec<NestedMetaItem>> {
         let mut tokens = tokens.trees().peekable();
         let mut result = ThinVec::new();
@@ -468,8 +464,9 @@ impl NestedMetaItem {
         self.meta_item().and_then(|meta_item| meta_item.meta_item_list())
     }
 
-    /// Returns a name and single literal value tuple of the `MetaItem`.
-    pub fn name_value_literal(&self) -> Option<(Symbol, &MetaItemLit)> {
+    /// If it's a singleton list of the form `foo(lit)`, returns the `foo` and
+    /// the `lit`.
+    pub fn singleton_lit_list(&self) -> Option<(Symbol, &MetaItemLit)> {
         self.meta_item().and_then(|meta_item| {
             meta_item.meta_item_list().and_then(|meta_item_list| {
                 if meta_item_list.len() == 1
diff --git a/compiler/rustc_ast/src/mut_visit.rs b/compiler/rustc_ast/src/mut_visit.rs
index 7dbfb7c7364..1cceca33c17 100644
--- a/compiler/rustc_ast/src/mut_visit.rs
+++ b/compiler/rustc_ast/src/mut_visit.rs
@@ -335,7 +335,7 @@ pub fn visit_clobber<T: DummyAstNode>(t: &mut T, f: impl FnOnce(T) -> T) {
 
 // No `noop_` prefix because there isn't a corresponding method in `MutVisitor`.
 #[inline]
-pub fn visit_vec<T, F>(elems: &mut Vec<T>, mut visit_elem: F)
+fn visit_vec<T, F>(elems: &mut Vec<T>, mut visit_elem: F)
 where
     F: FnMut(&mut T),
 {
@@ -346,7 +346,7 @@ where
 
 // No `noop_` prefix because there isn't a corresponding method in `MutVisitor`.
 #[inline]
-pub fn visit_thin_vec<T, F>(elems: &mut ThinVec<T>, mut visit_elem: F)
+fn visit_thin_vec<T, F>(elems: &mut ThinVec<T>, mut visit_elem: F)
 where
     F: FnMut(&mut T),
 {
@@ -357,7 +357,7 @@ where
 
 // No `noop_` prefix because there isn't a corresponding method in `MutVisitor`.
 #[inline]
-pub fn visit_opt<T, F>(opt: &mut Option<T>, mut visit_elem: F)
+fn visit_opt<T, F>(opt: &mut Option<T>, mut visit_elem: F)
 where
     F: FnMut(&mut T),
 {
@@ -367,36 +367,37 @@ where
 }
 
 // No `noop_` prefix because there isn't a corresponding method in `MutVisitor`.
-pub fn visit_attrs<T: MutVisitor>(attrs: &mut AttrVec, vis: &mut T) {
+fn visit_attrs<T: MutVisitor>(attrs: &mut AttrVec, vis: &mut T) {
     for attr in attrs.iter_mut() {
         vis.visit_attribute(attr);
     }
 }
 
 // No `noop_` prefix because there isn't a corresponding method in `MutVisitor`.
-pub fn visit_exprs<T: MutVisitor>(exprs: &mut Vec<P<Expr>>, vis: &mut T) {
+#[allow(unused)]
+fn visit_exprs<T: MutVisitor>(exprs: &mut Vec<P<Expr>>, vis: &mut T) {
     exprs.flat_map_in_place(|expr| vis.filter_map_expr(expr))
 }
 
 // No `noop_` prefix because there isn't a corresponding method in `MutVisitor`.
-pub fn visit_thin_exprs<T: MutVisitor>(exprs: &mut ThinVec<P<Expr>>, vis: &mut T) {
+fn visit_thin_exprs<T: MutVisitor>(exprs: &mut ThinVec<P<Expr>>, vis: &mut T) {
     exprs.flat_map_in_place(|expr| vis.filter_map_expr(expr))
 }
 
 // No `noop_` prefix because there isn't a corresponding method in `MutVisitor`.
-pub fn visit_bounds<T: MutVisitor>(bounds: &mut GenericBounds, vis: &mut T) {
+fn visit_bounds<T: MutVisitor>(bounds: &mut GenericBounds, vis: &mut T) {
     visit_vec(bounds, |bound| vis.visit_param_bound(bound));
 }
 
 // No `noop_` prefix because there isn't a corresponding method in `MutVisitor`.
-pub fn visit_fn_sig<T: MutVisitor>(FnSig { header, decl, span }: &mut FnSig, vis: &mut T) {
+fn visit_fn_sig<T: MutVisitor>(FnSig { header, decl, span }: &mut FnSig, vis: &mut T) {
     vis.visit_fn_header(header);
     vis.visit_fn_decl(decl);
     vis.visit_span(span);
 }
 
 // No `noop_` prefix because there isn't a corresponding method in `MutVisitor`.
-pub fn visit_attr_args<T: MutVisitor>(args: &mut AttrArgs, vis: &mut T) {
+fn visit_attr_args<T: MutVisitor>(args: &mut AttrArgs, vis: &mut T) {
     match args {
         AttrArgs::Empty => {}
         AttrArgs::Delimited(args) => visit_delim_args(args, vis),
@@ -411,7 +412,7 @@ pub fn visit_attr_args<T: MutVisitor>(args: &mut AttrArgs, vis: &mut T) {
 }
 
 // No `noop_` prefix because there isn't a corresponding method in `MutVisitor`.
-pub fn visit_delim_args<T: MutVisitor>(args: &mut DelimArgs, vis: &mut T) {
+fn visit_delim_args<T: MutVisitor>(args: &mut DelimArgs, vis: &mut T) {
     let DelimArgs { dspan, delim: _, tokens } = args;
     visit_delim_span(dspan, vis);
     visit_tts(tokens, vis);
@@ -435,7 +436,7 @@ pub fn noop_flat_map_pat_field<T: MutVisitor>(
     smallvec![fp]
 }
 
-pub fn noop_visit_use_tree<T: MutVisitor>(use_tree: &mut UseTree, vis: &mut T) {
+fn noop_visit_use_tree<T: MutVisitor>(use_tree: &mut UseTree, vis: &mut T) {
     let UseTree { prefix, kind, span } = use_tree;
     vis.visit_path(prefix);
     match kind {
@@ -462,7 +463,7 @@ pub fn noop_flat_map_arm<T: MutVisitor>(mut arm: Arm, vis: &mut T) -> SmallVec<[
     smallvec![arm]
 }
 
-pub fn noop_visit_constraint<T: MutVisitor>(
+fn noop_visit_constraint<T: MutVisitor>(
     AssocConstraint { id, ident, gen_args, kind, span }: &mut AssocConstraint,
     vis: &mut T,
 ) {
@@ -541,7 +542,7 @@ pub fn noop_visit_ty<T: MutVisitor>(ty: &mut P<Ty>, vis: &mut T) {
     visit_lazy_tts(tokens, vis);
 }
 
-pub fn noop_visit_foreign_mod<T: MutVisitor>(foreign_mod: &mut ForeignMod, vis: &mut T) {
+fn noop_visit_foreign_mod<T: MutVisitor>(foreign_mod: &mut ForeignMod, vis: &mut T) {
     let ForeignMod { unsafety, abi: _, items } = foreign_mod;
     visit_unsafety(unsafety, vis);
     items.flat_map_in_place(|item| vis.flat_map_foreign_item(item));
@@ -562,11 +563,11 @@ pub fn noop_flat_map_variant<T: MutVisitor>(
     smallvec![variant]
 }
 
-pub fn noop_visit_ident<T: MutVisitor>(Ident { name: _, span }: &mut Ident, vis: &mut T) {
+fn noop_visit_ident<T: MutVisitor>(Ident { name: _, span }: &mut Ident, vis: &mut T) {
     vis.visit_span(span);
 }
 
-pub fn noop_visit_path<T: MutVisitor>(Path { segments, span, tokens }: &mut Path, vis: &mut T) {
+fn noop_visit_path<T: MutVisitor>(Path { segments, span, tokens }: &mut Path, vis: &mut T) {
     vis.visit_span(span);
     for PathSegment { ident, id, args } in segments {
         vis.visit_ident(ident);
@@ -576,7 +577,7 @@ pub fn noop_visit_path<T: MutVisitor>(Path { segments, span, tokens }: &mut Path
     visit_lazy_tts(tokens, vis);
 }
 
-pub fn noop_visit_qself<T: MutVisitor>(qself: &mut Option<P<QSelf>>, vis: &mut T) {
+fn noop_visit_qself<T: MutVisitor>(qself: &mut Option<P<QSelf>>, vis: &mut T) {
     visit_opt(qself, |qself| {
         let QSelf { ty, path_span, position: _ } = &mut **qself;
         vis.visit_ty(ty);
@@ -584,14 +585,14 @@ pub fn noop_visit_qself<T: MutVisitor>(qself: &mut Option<P<QSelf>>, vis: &mut T
     })
 }
 
-pub fn noop_visit_generic_args<T: MutVisitor>(generic_args: &mut GenericArgs, vis: &mut T) {
+fn noop_visit_generic_args<T: MutVisitor>(generic_args: &mut GenericArgs, vis: &mut T) {
     match generic_args {
         GenericArgs::AngleBracketed(data) => vis.visit_angle_bracketed_parameter_data(data),
         GenericArgs::Parenthesized(data) => vis.visit_parenthesized_parameter_data(data),
     }
 }
 
-pub fn noop_visit_generic_arg<T: MutVisitor>(arg: &mut GenericArg, vis: &mut T) {
+fn noop_visit_generic_arg<T: MutVisitor>(arg: &mut GenericArg, vis: &mut T) {
     match arg {
         GenericArg::Lifetime(lt) => vis.visit_lifetime(lt),
         GenericArg::Type(ty) => vis.visit_ty(ty),
@@ -599,7 +600,7 @@ pub fn noop_visit_generic_arg<T: MutVisitor>(arg: &mut GenericArg, vis: &mut T)
     }
 }
 
-pub fn noop_visit_angle_bracketed_parameter_data<T: MutVisitor>(
+fn noop_visit_angle_bracketed_parameter_data<T: MutVisitor>(
     data: &mut AngleBracketedArgs,
     vis: &mut T,
 ) {
@@ -611,7 +612,7 @@ pub fn noop_visit_angle_bracketed_parameter_data<T: MutVisitor>(
     vis.visit_span(span);
 }
 
-pub fn noop_visit_parenthesized_parameter_data<T: MutVisitor>(
+fn noop_visit_parenthesized_parameter_data<T: MutVisitor>(
     args: &mut ParenthesizedArgs,
     vis: &mut T,
 ) {
@@ -621,7 +622,7 @@ pub fn noop_visit_parenthesized_parameter_data<T: MutVisitor>(
     vis.visit_span(span);
 }
 
-pub fn noop_visit_local<T: MutVisitor>(local: &mut P<Local>, vis: &mut T) {
+fn noop_visit_local<T: MutVisitor>(local: &mut P<Local>, vis: &mut T) {
     let Local { id, pat, ty, kind, span, colon_sp, attrs, tokens } = local.deref_mut();
     vis.visit_id(id);
     vis.visit_pat(pat);
@@ -642,7 +643,7 @@ pub fn noop_visit_local<T: MutVisitor>(local: &mut P<Local>, vis: &mut T) {
     visit_lazy_tts(tokens, vis);
 }
 
-pub fn noop_visit_attribute<T: MutVisitor>(attr: &mut Attribute, vis: &mut T) {
+fn noop_visit_attribute<T: MutVisitor>(attr: &mut Attribute, vis: &mut T) {
     let Attribute { kind, id: _, style: _, span } = attr;
     match kind {
         AttrKind::Normal(normal) => {
@@ -658,25 +659,25 @@ pub fn noop_visit_attribute<T: MutVisitor>(attr: &mut Attribute, vis: &mut T) {
     vis.visit_span(span);
 }
 
-pub fn noop_visit_mac<T: MutVisitor>(mac: &mut MacCall, vis: &mut T) {
+fn noop_visit_mac<T: MutVisitor>(mac: &mut MacCall, vis: &mut T) {
     let MacCall { path, args } = mac;
     vis.visit_path(path);
     visit_delim_args(args, vis);
 }
 
-pub fn noop_visit_macro_def<T: MutVisitor>(macro_def: &mut MacroDef, vis: &mut T) {
+fn noop_visit_macro_def<T: MutVisitor>(macro_def: &mut MacroDef, vis: &mut T) {
     let MacroDef { body, macro_rules: _ } = macro_def;
     visit_delim_args(body, vis);
 }
 
-pub fn noop_visit_meta_list_item<T: MutVisitor>(li: &mut NestedMetaItem, vis: &mut T) {
+fn noop_visit_meta_list_item<T: MutVisitor>(li: &mut NestedMetaItem, vis: &mut T) {
     match li {
         NestedMetaItem::MetaItem(mi) => vis.visit_meta_item(mi),
         NestedMetaItem::Lit(_lit) => {}
     }
 }
 
-pub fn noop_visit_meta_item<T: MutVisitor>(mi: &mut MetaItem, vis: &mut T) {
+fn noop_visit_meta_item<T: MutVisitor>(mi: &mut MetaItem, vis: &mut T) {
     let MetaItem { path: _, kind, span } = mi;
     match kind {
         MetaItemKind::Word => {}
@@ -697,7 +698,7 @@ pub fn noop_flat_map_param<T: MutVisitor>(mut param: Param, vis: &mut T) -> Smal
 }
 
 // No `noop_` prefix because there isn't a corresponding method in `MutVisitor`.
-pub fn visit_attr_tt<T: MutVisitor>(tt: &mut AttrTokenTree, vis: &mut T) {
+fn visit_attr_tt<T: MutVisitor>(tt: &mut AttrTokenTree, vis: &mut T) {
     match tt {
         AttrTokenTree::Token(token, _) => {
             visit_token(token, vis);
@@ -724,7 +725,7 @@ pub fn visit_attr_tt<T: MutVisitor>(tt: &mut AttrTokenTree, vis: &mut T) {
 }
 
 // No `noop_` prefix because there isn't a corresponding method in `MutVisitor`.
-pub fn visit_tt<T: MutVisitor>(tt: &mut TokenTree, vis: &mut T) {
+fn visit_tt<T: MutVisitor>(tt: &mut TokenTree, vis: &mut T) {
     match tt {
         TokenTree::Token(token, _) => {
             visit_token(token, vis);
@@ -738,24 +739,21 @@ pub fn visit_tt<T: MutVisitor>(tt: &mut TokenTree, vis: &mut T) {
 }
 
 // No `noop_` prefix because there isn't a corresponding method in `MutVisitor`.
-pub fn visit_tts<T: MutVisitor>(TokenStream(tts): &mut TokenStream, vis: &mut T) {
+fn visit_tts<T: MutVisitor>(TokenStream(tts): &mut TokenStream, vis: &mut T) {
     if T::VISIT_TOKENS && !tts.is_empty() {
         let tts = Lrc::make_mut(tts);
         visit_vec(tts, |tree| visit_tt(tree, vis));
     }
 }
 
-pub fn visit_attr_tts<T: MutVisitor>(AttrTokenStream(tts): &mut AttrTokenStream, vis: &mut T) {
+fn visit_attr_tts<T: MutVisitor>(AttrTokenStream(tts): &mut AttrTokenStream, vis: &mut T) {
     if T::VISIT_TOKENS && !tts.is_empty() {
         let tts = Lrc::make_mut(tts);
         visit_vec(tts, |tree| visit_attr_tt(tree, vis));
     }
 }
 
-pub fn visit_lazy_tts_opt_mut<T: MutVisitor>(
-    lazy_tts: Option<&mut LazyAttrTokenStream>,
-    vis: &mut T,
-) {
+fn visit_lazy_tts_opt_mut<T: MutVisitor>(lazy_tts: Option<&mut LazyAttrTokenStream>, vis: &mut T) {
     if T::VISIT_TOKENS {
         if let Some(lazy_tts) = lazy_tts {
             let mut tts = lazy_tts.to_attr_token_stream();
@@ -765,7 +763,7 @@ pub fn visit_lazy_tts_opt_mut<T: MutVisitor>(
     }
 }
 
-pub fn visit_lazy_tts<T: MutVisitor>(lazy_tts: &mut Option<LazyAttrTokenStream>, vis: &mut T) {
+fn visit_lazy_tts<T: MutVisitor>(lazy_tts: &mut Option<LazyAttrTokenStream>, vis: &mut T) {
     visit_lazy_tts_opt_mut(lazy_tts.as_mut(), vis);
 }
 
@@ -818,7 +816,7 @@ pub fn visit_token<T: MutVisitor>(t: &mut Token, vis: &mut T) {
 // contain multiple items, but decided against it when I looked at
 // `parse_item_or_view_item` and tried to figure out what I would do with
 // multiple items there....
-pub fn visit_nonterminal<T: MutVisitor>(nt: &mut token::Nonterminal, vis: &mut T) {
+fn visit_nonterminal<T: MutVisitor>(nt: &mut token::Nonterminal, vis: &mut T) {
     match nt {
         token::NtItem(item) => visit_clobber(item, |item| {
             // This is probably okay, because the only visitors likely to
@@ -851,7 +849,7 @@ pub fn visit_nonterminal<T: MutVisitor>(nt: &mut token::Nonterminal, vis: &mut T
 }
 
 // No `noop_` prefix because there isn't a corresponding method in `MutVisitor`.
-pub fn visit_defaultness<T: MutVisitor>(defaultness: &mut Defaultness, vis: &mut T) {
+fn visit_defaultness<T: MutVisitor>(defaultness: &mut Defaultness, vis: &mut T) {
     match defaultness {
         Defaultness::Default(span) => vis.visit_span(span),
         Defaultness::Final => {}
@@ -859,7 +857,7 @@ pub fn visit_defaultness<T: MutVisitor>(defaultness: &mut Defaultness, vis: &mut
 }
 
 // No `noop_` prefix because there isn't a corresponding method in `MutVisitor`.
-pub fn visit_unsafety<T: MutVisitor>(unsafety: &mut Unsafe, vis: &mut T) {
+fn visit_unsafety<T: MutVisitor>(unsafety: &mut Unsafe, vis: &mut T) {
     match unsafety {
         Unsafe::Yes(span) => vis.visit_span(span),
         Unsafe::No => {}
@@ -867,7 +865,7 @@ pub fn visit_unsafety<T: MutVisitor>(unsafety: &mut Unsafe, vis: &mut T) {
 }
 
 // No `noop_` prefix because there isn't a corresponding method in `MutVisitor`.
-pub fn visit_polarity<T: MutVisitor>(polarity: &mut ImplPolarity, vis: &mut T) {
+fn visit_polarity<T: MutVisitor>(polarity: &mut ImplPolarity, vis: &mut T) {
     match polarity {
         ImplPolarity::Positive => {}
         ImplPolarity::Negative(span) => vis.visit_span(span),
@@ -875,14 +873,14 @@ pub fn visit_polarity<T: MutVisitor>(polarity: &mut ImplPolarity, vis: &mut T) {
 }
 
 // No `noop_` prefix because there isn't a corresponding method in `MutVisitor`.
-pub fn visit_constness<T: MutVisitor>(constness: &mut Const, vis: &mut T) {
+fn visit_constness<T: MutVisitor>(constness: &mut Const, vis: &mut T) {
     match constness {
         Const::Yes(span) => vis.visit_span(span),
         Const::No => {}
     }
 }
 
-pub fn noop_visit_closure_binder<T: MutVisitor>(binder: &mut ClosureBinder, vis: &mut T) {
+fn noop_visit_closure_binder<T: MutVisitor>(binder: &mut ClosureBinder, vis: &mut T) {
     match binder {
         ClosureBinder::NotPresent => {}
         ClosureBinder::For { span: _, generic_params } => {
@@ -891,7 +889,7 @@ pub fn noop_visit_closure_binder<T: MutVisitor>(binder: &mut ClosureBinder, vis:
     }
 }
 
-pub fn noop_visit_coroutine_kind<T: MutVisitor>(coroutine_kind: &mut CoroutineKind, vis: &mut T) {
+fn noop_visit_coroutine_kind<T: MutVisitor>(coroutine_kind: &mut CoroutineKind, vis: &mut T) {
     match coroutine_kind {
         CoroutineKind::Async { span, closure_id, return_impl_trait_id }
         | CoroutineKind::Gen { span, closure_id, return_impl_trait_id }
@@ -903,27 +901,27 @@ pub fn noop_visit_coroutine_kind<T: MutVisitor>(coroutine_kind: &mut CoroutineKi
     }
 }
 
-pub fn noop_visit_fn_decl<T: MutVisitor>(decl: &mut P<FnDecl>, vis: &mut T) {
+fn noop_visit_fn_decl<T: MutVisitor>(decl: &mut P<FnDecl>, vis: &mut T) {
     let FnDecl { inputs, output } = decl.deref_mut();
     inputs.flat_map_in_place(|param| vis.flat_map_param(param));
     noop_visit_fn_ret_ty(output, vis);
 }
 
-pub fn noop_visit_fn_ret_ty<T: MutVisitor>(fn_ret_ty: &mut FnRetTy, vis: &mut T) {
+fn noop_visit_fn_ret_ty<T: MutVisitor>(fn_ret_ty: &mut FnRetTy, vis: &mut T) {
     match fn_ret_ty {
         FnRetTy::Default(span) => vis.visit_span(span),
         FnRetTy::Ty(ty) => vis.visit_ty(ty),
     }
 }
 
-pub fn noop_visit_param_bound<T: MutVisitor>(pb: &mut GenericBound, vis: &mut T) {
+fn noop_visit_param_bound<T: MutVisitor>(pb: &mut GenericBound, vis: &mut T) {
     match pb {
         GenericBound::Trait(ty, _modifier) => vis.visit_poly_trait_ref(ty),
         GenericBound::Outlives(lifetime) => noop_visit_lifetime(lifetime, vis),
     }
 }
 
-pub fn noop_visit_precise_capturing_arg<T: MutVisitor>(arg: &mut PreciseCapturingArg, vis: &mut T) {
+fn noop_visit_precise_capturing_arg<T: MutVisitor>(arg: &mut PreciseCapturingArg, vis: &mut T) {
     match arg {
         PreciseCapturingArg::Lifetime(lt) => {
             vis.visit_lifetime(lt);
@@ -960,7 +958,7 @@ pub fn noop_flat_map_generic_param<T: MutVisitor>(
     smallvec![param]
 }
 
-pub fn noop_visit_label<T: MutVisitor>(Label { ident }: &mut Label, vis: &mut T) {
+fn noop_visit_label<T: MutVisitor>(Label { ident }: &mut Label, vis: &mut T) {
     vis.visit_ident(ident);
 }
 
@@ -969,20 +967,20 @@ fn noop_visit_lifetime<T: MutVisitor>(Lifetime { id, ident }: &mut Lifetime, vis
     vis.visit_ident(ident);
 }
 
-pub fn noop_visit_generics<T: MutVisitor>(generics: &mut Generics, vis: &mut T) {
+fn noop_visit_generics<T: MutVisitor>(generics: &mut Generics, vis: &mut T) {
     let Generics { params, where_clause, span } = generics;
     params.flat_map_in_place(|param| vis.flat_map_generic_param(param));
     vis.visit_where_clause(where_clause);
     vis.visit_span(span);
 }
 
-pub fn noop_visit_where_clause<T: MutVisitor>(wc: &mut WhereClause, vis: &mut T) {
+fn noop_visit_where_clause<T: MutVisitor>(wc: &mut WhereClause, vis: &mut T) {
     let WhereClause { has_where_token: _, predicates, span } = wc;
     visit_thin_vec(predicates, |predicate| vis.visit_where_predicate(predicate));
     vis.visit_span(span);
 }
 
-pub fn noop_visit_where_predicate<T: MutVisitor>(pred: &mut WherePredicate, vis: &mut T) {
+fn noop_visit_where_predicate<T: MutVisitor>(pred: &mut WherePredicate, vis: &mut T) {
     match pred {
         WherePredicate::BoundPredicate(bp) => {
             let WhereBoundPredicate { span, bound_generic_params, bounded_ty, bounds } = bp;
@@ -1006,7 +1004,7 @@ pub fn noop_visit_where_predicate<T: MutVisitor>(pred: &mut WherePredicate, vis:
     }
 }
 
-pub fn noop_visit_variant_data<T: MutVisitor>(vdata: &mut VariantData, vis: &mut T) {
+fn noop_visit_variant_data<T: MutVisitor>(vdata: &mut VariantData, vis: &mut T) {
     match vdata {
         VariantData::Struct { fields, .. } => {
             fields.flat_map_in_place(|field| vis.flat_map_field_def(field));
@@ -1019,12 +1017,12 @@ pub fn noop_visit_variant_data<T: MutVisitor>(vdata: &mut VariantData, vis: &mut
     }
 }
 
-pub fn noop_visit_trait_ref<T: MutVisitor>(TraitRef { path, ref_id }: &mut TraitRef, vis: &mut T) {
+fn noop_visit_trait_ref<T: MutVisitor>(TraitRef { path, ref_id }: &mut TraitRef, vis: &mut T) {
     vis.visit_path(path);
     vis.visit_id(ref_id);
 }
 
-pub fn noop_visit_poly_trait_ref<T: MutVisitor>(p: &mut PolyTraitRef, vis: &mut T) {
+fn noop_visit_poly_trait_ref<T: MutVisitor>(p: &mut PolyTraitRef, vis: &mut T) {
     let PolyTraitRef { bound_generic_params, trait_ref, span } = p;
     bound_generic_params.flat_map_in_place(|param| vis.flat_map_generic_param(param));
     vis.visit_trait_ref(trait_ref);
@@ -1058,7 +1056,7 @@ pub fn noop_flat_map_expr_field<T: MutVisitor>(
     smallvec![f]
 }
 
-pub fn noop_visit_mt<T: MutVisitor>(MutTy { ty, mutbl: _ }: &mut MutTy, vis: &mut T) {
+fn noop_visit_mt<T: MutVisitor>(MutTy { ty, mutbl: _ }: &mut MutTy, vis: &mut T) {
     vis.visit_ty(ty);
 }
 
@@ -1225,7 +1223,7 @@ fn visit_const_item<T: MutVisitor>(
     visit_opt(expr, |expr| visitor.visit_expr(expr));
 }
 
-pub fn noop_visit_fn_header<T: MutVisitor>(header: &mut FnHeader, vis: &mut T) {
+fn noop_visit_fn_header<T: MutVisitor>(header: &mut FnHeader, vis: &mut T) {
     let FnHeader { unsafety, coroutine_kind, constness, ext: _ } = header;
     visit_constness(constness, vis);
     coroutine_kind.as_mut().map(|coroutine_kind| vis.visit_coroutine_kind(coroutine_kind));
@@ -1343,12 +1341,12 @@ pub fn noop_visit_pat<T: MutVisitor>(pat: &mut P<Pat>, vis: &mut T) {
     visit_lazy_tts(tokens, vis);
 }
 
-pub fn noop_visit_anon_const<T: MutVisitor>(AnonConst { id, value }: &mut AnonConst, vis: &mut T) {
+fn noop_visit_anon_const<T: MutVisitor>(AnonConst { id, value }: &mut AnonConst, vis: &mut T) {
     vis.visit_id(id);
     vis.visit_expr(value);
 }
 
-pub fn noop_visit_inline_asm<T: MutVisitor>(asm: &mut InlineAsm, vis: &mut T) {
+fn noop_visit_inline_asm<T: MutVisitor>(asm: &mut InlineAsm, vis: &mut T) {
     for (op, _) in &mut asm.operands {
         match op {
             InlineAsmOperand::In { expr, .. }
@@ -1368,7 +1366,7 @@ pub fn noop_visit_inline_asm<T: MutVisitor>(asm: &mut InlineAsm, vis: &mut T) {
     }
 }
 
-pub fn noop_visit_inline_asm_sym<T: MutVisitor>(
+fn noop_visit_inline_asm_sym<T: MutVisitor>(
     InlineAsmSym { id, qself, path }: &mut InlineAsmSym,
     vis: &mut T,
 ) {
@@ -1377,7 +1375,7 @@ pub fn noop_visit_inline_asm_sym<T: MutVisitor>(
     vis.visit_path(path);
 }
 
-pub fn noop_visit_format_args<T: MutVisitor>(fmt: &mut FormatArgs, vis: &mut T) {
+fn noop_visit_format_args<T: MutVisitor>(fmt: &mut FormatArgs, vis: &mut T) {
     for arg in fmt.arguments.all_args_mut() {
         if let FormatArgumentKind::Named(name) = &mut arg.kind {
             vis.visit_ident(name);
@@ -1594,10 +1592,7 @@ pub fn noop_flat_map_stmt<T: MutVisitor>(
     stmts
 }
 
-pub fn noop_flat_map_stmt_kind<T: MutVisitor>(
-    kind: StmtKind,
-    vis: &mut T,
-) -> SmallVec<[StmtKind; 1]> {
+fn noop_flat_map_stmt_kind<T: MutVisitor>(kind: StmtKind, vis: &mut T) -> SmallVec<[StmtKind; 1]> {
     match kind {
         StmtKind::Let(mut local) => smallvec![StmtKind::Let({
             vis.visit_local(&mut local);
@@ -1617,7 +1612,7 @@ pub fn noop_flat_map_stmt_kind<T: MutVisitor>(
     }
 }
 
-pub fn noop_visit_vis<T: MutVisitor>(visibility: &mut Visibility, vis: &mut T) {
+fn noop_visit_vis<T: MutVisitor>(visibility: &mut Visibility, vis: &mut T) {
     match &mut visibility.kind {
         VisibilityKind::Public | VisibilityKind::Inherited => {}
         VisibilityKind::Restricted { path, id, shorthand: _ } => {
@@ -1628,7 +1623,7 @@ pub fn noop_visit_vis<T: MutVisitor>(visibility: &mut Visibility, vis: &mut T) {
     vis.visit_span(&mut visibility.span);
 }
 
-pub fn noop_visit_capture_by<T: MutVisitor>(capture_by: &mut CaptureBy, vis: &mut T) {
+fn noop_visit_capture_by<T: MutVisitor>(capture_by: &mut CaptureBy, vis: &mut T) {
     match capture_by {
         CaptureBy::Ref => {}
         CaptureBy::Value { move_kw } => {
diff --git a/compiler/rustc_ast/src/tokenstream.rs b/compiler/rustc_ast/src/tokenstream.rs
index 880f92bbe7b..08d65a5ffa5 100644
--- a/compiler/rustc_ast/src/tokenstream.rs
+++ b/compiler/rustc_ast/src/tokenstream.rs
@@ -140,9 +140,8 @@ impl fmt::Debug for LazyAttrTokenStream {
 }
 
 impl<S: SpanEncoder> Encodable<S> for LazyAttrTokenStream {
-    fn encode(&self, s: &mut S) {
-        // Used by AST json printing.
-        Encodable::encode(&self.to_attr_token_stream(), s);
+    fn encode(&self, _s: &mut S) {
+        panic!("Attempted to encode LazyAttrTokenStream");
     }
 }
 
diff --git a/compiler/rustc_attr/src/builtin.rs b/compiler/rustc_attr/src/builtin.rs
index 439f13e7635..1c2077372e1 100644
--- a/compiler/rustc_attr/src/builtin.rs
+++ b/compiler/rustc_attr/src/builtin.rs
@@ -986,7 +986,7 @@ pub fn parse_repr_attr(sess: &Session, attr: &Attribute) -> Vec<ReprAttr> {
                     recognised = true;
                     acc.push(h);
                 }
-            } else if let Some((name, value)) = item.name_value_literal() {
+            } else if let Some((name, value)) = item.singleton_lit_list() {
                 let mut literal_error = None;
                 let mut err_span = item.span();
                 if name == sym::align {
diff --git a/compiler/rustc_codegen_ssa/src/codegen_attrs.rs b/compiler/rustc_codegen_ssa/src/codegen_attrs.rs
index 9c9e134f033..c28b0d644e6 100644
--- a/compiler/rustc_codegen_ssa/src/codegen_attrs.rs
+++ b/compiler/rustc_codegen_ssa/src/codegen_attrs.rs
@@ -435,7 +435,7 @@ fn codegen_fn_attrs(tcx: TyCtxt<'_>, did: LocalDefId) -> CodegenFnAttrs {
             sym::repr => {
                 codegen_fn_attrs.alignment = if let Some(items) = attr.meta_item_list()
                     && let [item] = items.as_slice()
-                    && let Some((sym::align, literal)) = item.name_value_literal()
+                    && let Some((sym::align, literal)) = item.singleton_lit_list()
                 {
                     rustc_attr::parse_alignment(&literal.kind)
                         .map_err(|msg| {
diff --git a/compiler/rustc_session/src/options.rs b/compiler/rustc_session/src/options.rs
index d5108058948..6a556e2a1f5 100644
--- a/compiler/rustc_session/src/options.rs
+++ b/compiler/rustc_session/src/options.rs
@@ -1,5 +1,4 @@
 use crate::config::*;
-
 use crate::search_paths::SearchPath;
 use crate::utils::NativeLib;
 use crate::{lint, EarlyDiagCtxt};
@@ -8,20 +7,17 @@ use rustc_data_structures::profiling::TimePassesFormat;
 use rustc_data_structures::stable_hasher::Hash64;
 use rustc_errors::ColorConfig;
 use rustc_errors::{LanguageIdentifier, TerminalUrl};
+use rustc_feature::UnstableFeatures;
+use rustc_span::edition::Edition;
+use rustc_span::RealFileName;
+use rustc_span::SourceFileHashAlgorithm;
 use rustc_target::spec::{
     CodeModel, LinkerFlavorCli, MergeFunctions, PanicStrategy, SanitizerSet, WasmCAbi,
 };
 use rustc_target::spec::{
     RelocModel, RelroLevel, SplitDebuginfo, StackProtector, TargetTriple, TlsModel,
 };
-
-use rustc_feature::UnstableFeatures;
-use rustc_span::edition::Edition;
-use rustc_span::RealFileName;
-use rustc_span::SourceFileHashAlgorithm;
-
 use std::collections::BTreeMap;
-
 use std::hash::{DefaultHasher, Hasher};
 use std::num::{IntErrorKind, NonZero};
 use std::path::PathBuf;
@@ -118,8 +114,8 @@ top_level_options!(
     /// incremental compilation cache before proceeding.
     ///
     /// - `[TRACKED_NO_CRATE_HASH]`
-    /// Same as `[TRACKED]`, but will not affect the crate hash. This is useful for options that only
-    /// affect the incremental cache.
+    /// Same as `[TRACKED]`, but will not affect the crate hash. This is useful for options that
+    /// only affect the incremental cache.
     ///
     /// - `[UNTRACKED]`
     /// Incremental compilation is not influenced by this option.
diff --git a/src/ci/github-actions/calculate-job-matrix.py b/src/ci/github-actions/calculate-job-matrix.py
index c24cefa8d89..124c22bd979 100755
--- a/src/ci/github-actions/calculate-job-matrix.py
+++ b/src/ci/github-actions/calculate-job-matrix.py
@@ -17,10 +17,13 @@ from typing import List, Dict, Any, Optional
 
 import yaml
 
+CI_DIR = Path(__file__).absolute().parent.parent
 JOBS_YAML_PATH = Path(__file__).absolute().parent / "jobs.yml"
 
+Job = Dict[str, Any]
 
-def name_jobs(jobs: List[Dict], prefix: str) -> List[Dict]:
+
+def name_jobs(jobs: List[Dict], prefix: str) -> List[Job]:
     """
     Add a `name` attribute to each job, based on its image and the given `prefix`.
     """
@@ -29,7 +32,7 @@ def name_jobs(jobs: List[Dict], prefix: str) -> List[Dict]:
     return jobs
 
 
-def add_base_env(jobs: List[Dict], environment: Dict[str, str]) -> List[Dict]:
+def add_base_env(jobs: List[Job], environment: Dict[str, str]) -> List[Job]:
     """
     Prepends `environment` to the `env` attribute of each job.
     The `env` of each job has higher precedence than `environment`.
@@ -77,7 +80,7 @@ def find_job_type(ctx: GitHubCtx) -> Optional[JobType]:
     return None
 
 
-def calculate_jobs(job_type: JobType, job_data: Dict[str, Any]) -> List[Dict[str, Any]]:
+def calculate_jobs(job_type: JobType, job_data: Dict[str, Any]) -> List[Job]:
     if job_type == JobType.PR:
         return add_base_env(name_jobs(job_data["pr"], "PR"), job_data["envs"]["pr"])
     elif job_type == JobType.Try:
@@ -88,6 +91,13 @@ def calculate_jobs(job_type: JobType, job_data: Dict[str, Any]) -> List[Dict[str
     return []
 
 
+def skip_jobs(jobs: List[Dict[str, Any]], channel: str) -> List[Job]:
+    """
+    Skip CI jobs that are not supposed to be executed on the given `channel`.
+    """
+    return [j for j in jobs if j.get("only_on_channel", channel) == channel]
+
+
 def get_github_ctx() -> GitHubCtx:
     return GitHubCtx(
         event_name=os.environ["GITHUB_EVENT_NAME"],
@@ -107,9 +117,13 @@ if __name__ == "__main__":
     job_type = find_job_type(github_ctx)
     logging.info(f"Job type: {job_type}")
 
+    with open(CI_DIR / "channel") as f:
+        channel = f.read().strip()
+
     jobs = []
     if job_type is not None:
         jobs = calculate_jobs(job_type, data)
+    jobs = skip_jobs(jobs, channel)
 
     logging.info(f"Output:\n{yaml.dump(jobs, indent=4)}")
     print(f"jobs={json.dumps(jobs)}")
diff --git a/src/ci/github-actions/ci.yml b/src/ci/github-actions/ci.yml
index 19d6b517552..bc4b1b815cf 100644
--- a/src/ci/github-actions/ci.yml
+++ b/src/ci/github-actions/ci.yml
@@ -107,9 +107,6 @@ x--expand-yaml-anchors--remove:
   - &job-aarch64-linux
     os: [self-hosted, ARM64, linux]
 
-  - &step
-    if: success() && !env.SKIP_JOB
-
   - &base-ci-job
     defaults:
       run:
@@ -151,7 +148,7 @@ x--expand-yaml-anchors--remove:
         run: echo "[CI_PR_NUMBER=$num]"
         env:
           num: ${{ github.event.number }}
-        if: success() && !env.SKIP_JOB && github.event_name == 'pull_request'
+        if: success() && github.event_name == 'pull_request'
 
       - name: add extra environment variables
         run: src/ci/scripts/setup-environment.sh
@@ -161,71 +158,51 @@ x--expand-yaml-anchors--remove:
           # are passed to the `setup-environment.sh` script encoded in JSON,
           # which then uses log commands to actually set them.
           EXTRA_VARIABLES: ${{ toJson(matrix.env) }}
-        <<: *step
-
-      - name: decide whether to skip this job
-        run: src/ci/scripts/should-skip-this.sh
-        <<: *step
 
       - name: ensure the channel matches the target branch
         run: src/ci/scripts/verify-channel.sh
-        <<: *step
 
       - name: collect CPU statistics
         run: src/ci/scripts/collect-cpu-stats.sh
-        <<: *step
 
       - name: show the current environment
         run: src/ci/scripts/dump-environment.sh
-        <<: *step
 
       - name: install awscli
         run: src/ci/scripts/install-awscli.sh
-        <<: *step
 
       - name: install sccache
         run: src/ci/scripts/install-sccache.sh
-        <<: *step
 
       - name: select Xcode
         run: src/ci/scripts/select-xcode.sh
-        <<: *step
 
       - name: install clang
         run: src/ci/scripts/install-clang.sh
-        <<: *step
 
       - name: install tidy
         run: src/ci/scripts/install-tidy.sh
-        <<: *step
 
       - name: install WIX
         run: src/ci/scripts/install-wix.sh
-        <<: *step
 
       - name: disable git crlf conversion
         run: src/ci/scripts/disable-git-crlf-conversion.sh
-        <<: *step
 
       - name: checkout submodules
         run: src/ci/scripts/checkout-submodules.sh
-        <<: *step
 
       - name: install MSYS2
         run: src/ci/scripts/install-msys2.sh
-        <<: *step
 
       - name: install MinGW
         run: src/ci/scripts/install-mingw.sh
-        <<: *step
 
       - name: install ninja
         run: src/ci/scripts/install-ninja.sh
-        <<: *step
 
       - name: enable ipv6 on Docker
         run: src/ci/scripts/enable-docker-ipv6.sh
-        <<: *step
 
       # Disable automatic line ending conversion (again). On Windows, when we're
       # installing dependencies, something switches the git configuration directory or
@@ -234,19 +211,15 @@ x--expand-yaml-anchors--remove:
       # appropriate line endings.
       - name: disable git crlf conversion
         run: src/ci/scripts/disable-git-crlf-conversion.sh
-        <<: *step
 
       - name: ensure line endings are correct
         run: src/ci/scripts/verify-line-endings.sh
-        <<: *step
 
       - name: ensure backported commits are in upstream branches
         run: src/ci/scripts/verify-backported-commits.sh
-        <<: *step
 
       - name: ensure the stable version number is correct
         run: src/ci/scripts/verify-stable-version-number.sh
-        <<: *step
 
       - name: run the build
         # Redirect stderr to stdout to avoid reordering the two streams in the GHA logs.
@@ -255,11 +228,9 @@ x--expand-yaml-anchors--remove:
           AWS_ACCESS_KEY_ID: ${{ env.CACHES_AWS_ACCESS_KEY_ID }}
           AWS_SECRET_ACCESS_KEY: ${{ secrets[format('AWS_SECRET_ACCESS_KEY_{0}', env.CACHES_AWS_ACCESS_KEY_ID)] }}
           TOOLSTATE_REPO_ACCESS_TOKEN: ${{ secrets.TOOLSTATE_REPO_ACCESS_TOKEN }}
-        <<: *step
 
       - name: create github artifacts
         run: src/ci/scripts/create-doc-artifacts.sh
-        <<: *step
 
       - name: upload artifacts to github
         uses: actions/upload-artifact@v4
@@ -269,7 +240,6 @@ x--expand-yaml-anchors--remove:
           path: obj/artifacts/doc
           if-no-files-found: ignore
           retention-days: 5
-        <<: *step
 
       - name: upload artifacts to S3
         run: src/ci/scripts/upload-artifacts.sh
@@ -281,8 +251,7 @@ x--expand-yaml-anchors--remove:
         # adding the condition is helpful as this way CI will not silently skip
         # deploying artifacts from a dist builder if the variables are misconfigured,
         # erroring about invalid credentials instead.
-        if: success() && !env.SKIP_JOB && (github.event_name == 'push' || env.DEPLOY == '1' || env.DEPLOY_ALT == '1')
-        <<: *step
+        if: success() && (github.event_name == 'push' || env.DEPLOY == '1' || env.DEPLOY_ALT == '1')
 
   # These snippets are used by the try-success, try-failure, auto-success and auto-failure jobs.
   # Check out their documentation for more information on why they're needed.
@@ -399,7 +368,6 @@ jobs:
         shell: bash
         env:
           TOOLSTATE_REPO_ACCESS_TOKEN: ${{ secrets.TOOLSTATE_REPO_ACCESS_TOKEN }}
-        <<: *step
 
   # These jobs don't actually test anything, but they're used to tell bors the
   # build completed, as there is no practical way to detect when a workflow is
diff --git a/src/ci/github-actions/jobs.yml b/src/ci/github-actions/jobs.yml
index ec58bd0924e..df6c5d6079d 100644
--- a/src/ci/github-actions/jobs.yml
+++ b/src/ci/github-actions/jobs.yml
@@ -79,7 +79,7 @@ pr:
     <<: *job-linux-16c
 
 # Jobs that run when you perform a try build (@bors try)
-# These jobs automatically inherit envs.production, to avoid repeating
+# These jobs automatically inherit envs.try, to avoid repeating
 # it in each job definition.
 try:
   - image: dist-x86_64-linux
@@ -88,7 +88,7 @@ try:
     <<: *job-linux-16c
 
 # Main CI jobs that have to be green to merge a commit into master
-# These jobs automatically inherit envs.production, to avoid repeating
+# These jobs automatically inherit envs.auto, to avoid repeating
 # it in each job definition.
 auto:
   #############################
@@ -200,24 +200,23 @@ auto:
   # channel name on the output), and this builder prevents landing
   # changes that would result in broken builds after a promotion.
   - image: x86_64-gnu-stable
+    # Only run this job on the nightly channel. Running this on beta
+    # could cause failures when `dev: 1` in `stage0.txt`, and running
+    # this on stable is useless.
+    only_on_channel: nightly
     env:
       IMAGE: x86_64-gnu
       RUST_CI_OVERRIDE_RELEASE_CHANNEL: stable
-      # Only run this job on the nightly channel. Running this on beta
-      # could cause failures when `dev: 1` in `stage0.txt`, and running
-      # this on stable is useless.
-      CI_ONLY_WHEN_CHANNEL: nightly
     <<: *job-linux-4c
 
   - image: x86_64-gnu-aux
     <<: *job-linux-4c
 
   - image: x86_64-gnu-integration
-    env:
-      # Only run this job on the nightly channel. Fuchsia requires
-      # nightly features to compile, and this job would fail if
-      # executed on beta and stable.
-      CI_ONLY_WHEN_CHANNEL: nightly
+    # Only run this job on the nightly channel. Fuchsia requires
+    # nightly features to compile, and this job would fail if
+    # executed on beta and stable.
+    only_on_channel: nightly
     <<: *job-linux-8c
 
   - image: x86_64-gnu-debug
diff --git a/src/ci/scripts/should-skip-this.sh b/src/ci/scripts/should-skip-this.sh
deleted file mode 100755
index 48127166ad0..00000000000
--- a/src/ci/scripts/should-skip-this.sh
+++ /dev/null
@@ -1,21 +0,0 @@
-#!/bin/bash
-# Set the SKIP_JOB environment variable if this job is not supposed to run on the current builder.
-
-set -euo pipefail
-IFS=$'\n\t'
-
-source "$(cd "$(dirname "$0")" && pwd)/../shared.sh"
-
-if [[ -n "${CI_ONLY_WHEN_CHANNEL-}" ]]; then
-    if [[ "${CI_ONLY_WHEN_CHANNEL}" = "$(cat src/ci/channel)" ]]; then
-        echo "The channel is the expected one"
-    else
-        echo "Not executing this job as the channel is not the expected one"
-        ciCommandSetEnv SKIP_JOB 1
-        exit 0
-    fi
-fi
-
-
-echo "Executing the job since there is no skip rule preventing the execution"
-exit 0
diff --git a/src/tools/run-make-support/Cargo.toml b/src/tools/run-make-support/Cargo.toml
index 3ea35c7940c..61a24c97e77 100644
--- a/src/tools/run-make-support/Cargo.toml
+++ b/src/tools/run-make-support/Cargo.toml
@@ -5,5 +5,6 @@ edition = "2021"
 
 [dependencies]
 object = "0.34.0"
+similar = "2.5.0"
 wasmparser = "0.118.2"
 regex = "1.8" # 1.8 to avoid memchr 2.6.0, as 2.5.0 is pinned in the workspace
diff --git a/src/tools/run-make-support/src/diff/mod.rs b/src/tools/run-make-support/src/diff/mod.rs
new file mode 100644
index 00000000000..54532c6e35b
--- /dev/null
+++ b/src/tools/run-make-support/src/diff/mod.rs
@@ -0,0 +1,81 @@
+use similar::TextDiff;
+use std::path::Path;
+
+#[cfg(test)]
+mod tests;
+
+pub fn diff() -> Diff {
+    Diff::new()
+}
+
+#[derive(Debug)]
+pub struct Diff {
+    expected: Option<String>,
+    expected_name: Option<String>,
+    actual: Option<String>,
+    actual_name: Option<String>,
+}
+
+impl Diff {
+    /// Construct a bare `diff` invocation.
+    pub fn new() -> Self {
+        Self { expected: None, expected_name: None, actual: None, actual_name: None }
+    }
+
+    /// Specify the expected output for the diff from a file.
+    pub fn expected_file<P: AsRef<Path>>(&mut self, path: P) -> &mut Self {
+        let path = path.as_ref();
+        let content = std::fs::read_to_string(path).expect("failed to read file");
+        let name = path.to_string_lossy().to_string();
+
+        self.expected = Some(content);
+        self.expected_name = Some(name);
+        self
+    }
+
+    /// Specify the expected output for the diff from a given text string.
+    pub fn expected_text<T: AsRef<[u8]>>(&mut self, name: &str, text: T) -> &mut Self {
+        self.expected = Some(String::from_utf8_lossy(text.as_ref()).to_string());
+        self.expected_name = Some(name.to_string());
+        self
+    }
+
+    /// Specify the actual output for the diff from a file.
+    pub fn actual_file<P: AsRef<Path>>(&mut self, path: P) -> &mut Self {
+        let path = path.as_ref();
+        let content = std::fs::read_to_string(path).expect("failed to read file");
+        let name = path.to_string_lossy().to_string();
+
+        self.actual = Some(content);
+        self.actual_name = Some(name);
+        self
+    }
+
+    /// Specify the actual output for the diff from a given text string.
+    pub fn actual_text<T: AsRef<[u8]>>(&mut self, name: &str, text: T) -> &mut Self {
+        self.actual = Some(String::from_utf8_lossy(text.as_ref()).to_string());
+        self.actual_name = Some(name.to_string());
+        self
+    }
+
+    /// Executes the diff process, prints any differences to the standard error.
+    #[track_caller]
+    pub fn run(&self) {
+        let expected = self.expected.as_ref().expect("expected text not set");
+        let actual = self.actual.as_ref().expect("actual text not set");
+        let expected_name = self.expected_name.as_ref().unwrap();
+        let actual_name = self.actual_name.as_ref().unwrap();
+
+        let output = TextDiff::from_lines(expected, actual)
+            .unified_diff()
+            .header(expected_name, actual_name)
+            .to_string();
+
+        if !output.is_empty() {
+            panic!(
+                "test failed: `{}` is different from `{}`\n\n{}",
+                expected_name, actual_name, output
+            )
+        }
+    }
+}
diff --git a/src/tools/run-make-support/src/diff/tests.rs b/src/tools/run-make-support/src/diff/tests.rs
new file mode 100644
index 00000000000..e6d72544b7e
--- /dev/null
+++ b/src/tools/run-make-support/src/diff/tests.rs
@@ -0,0 +1,39 @@
+#[cfg(test)]
+mod tests {
+    use crate::*;
+
+    #[test]
+    fn test_diff() {
+        let expected = "foo\nbar\nbaz\n";
+        let actual = "foo\nbar\nbaz\n";
+        diff().expected_text("EXPECTED_TEXT", expected).actual_text("ACTUAL_TEXT", actual).run();
+    }
+
+    #[test]
+    fn test_should_panic() {
+        let expected = "foo\nbar\nbaz\n";
+        let actual = "foo\nbaz\nbar\n";
+
+        let output = std::panic::catch_unwind(|| {
+            diff()
+                .expected_text("EXPECTED_TEXT", expected)
+                .actual_text("ACTUAL_TEXT", actual)
+                .run();
+        })
+        .unwrap_err();
+
+        let expected_output = "\
+test failed: `EXPECTED_TEXT` is different from `ACTUAL_TEXT`
+
+--- EXPECTED_TEXT
++++ ACTUAL_TEXT
+@@ -1,3 +1,3 @@
+ foo
++baz
+ bar
+-baz
+";
+
+        assert_eq!(output.downcast_ref::<String>().unwrap(), expected_output);
+    }
+}
diff --git a/src/tools/run-make-support/src/lib.rs b/src/tools/run-make-support/src/lib.rs
index e723e824ed6..76e8838d27c 100644
--- a/src/tools/run-make-support/src/lib.rs
+++ b/src/tools/run-make-support/src/lib.rs
@@ -5,6 +5,7 @@
 
 pub mod cc;
 pub mod clang;
+pub mod diff;
 pub mod llvm_readobj;
 pub mod run;
 pub mod rustc;
@@ -20,6 +21,7 @@ pub use wasmparser;
 
 pub use cc::{cc, extra_c_flags, extra_cxx_flags, Cc};
 pub use clang::{clang, Clang};
+pub use diff::{diff, Diff};
 pub use llvm_readobj::{llvm_readobj, LlvmReadobj};
 pub use run::{run, run_fail};
 pub use rustc::{aux_build, rustc, Rustc};
diff --git a/src/tools/run-make-support/src/rustc.rs b/src/tools/run-make-support/src/rustc.rs
index 9bf41c6e2e9..ddaae3236c2 100644
--- a/src/tools/run-make-support/src/rustc.rs
+++ b/src/tools/run-make-support/src/rustc.rs
@@ -148,6 +148,13 @@ impl Rustc {
         self
     }
 
+    /// Specify the print request.
+    pub fn print(&mut self, request: &str) -> &mut Self {
+        self.cmd.arg("--print");
+        self.cmd.arg(request);
+        self
+    }
+
     /// Add an extra argument to the linker invocation, via `-Clink-arg`.
     pub fn link_arg(&mut self, link_arg: &str) -> &mut Self {
         self.cmd.arg(format!("-Clink-arg={link_arg}"));
diff --git a/src/tools/tidy/src/allowed_run_make_makefiles.txt b/src/tools/tidy/src/allowed_run_make_makefiles.txt
index 93188b4fbae..9b3c0d0f1a5 100644
--- a/src/tools/tidy/src/allowed_run_make_makefiles.txt
+++ b/src/tools/tidy/src/allowed_run_make_makefiles.txt
@@ -189,7 +189,6 @@ run-make/no-builtins-attribute/Makefile
 run-make/no-builtins-lto/Makefile
 run-make/no-cdylib-as-rdylib/Makefile
 run-make/no-duplicate-libs/Makefile
-run-make/no-input-file/Makefile
 run-make/no-intermediate-extras/Makefile
 run-make/obey-crate-type-flag/Makefile
 run-make/optimization-remarks-dir-pgo/Makefile
diff --git a/tests/run-make/no-input-file/Makefile b/tests/run-make/no-input-file/Makefile
deleted file mode 100644
index a754573a524..00000000000
--- a/tests/run-make/no-input-file/Makefile
+++ /dev/null
@@ -1,4 +0,0 @@
-include ../tools.mk
-
-all:
-	$(RUSTC) --print crate-name 2>&1 | diff - no-input-file.stderr
diff --git a/tests/run-make/no-input-file/rmake.rs b/tests/run-make/no-input-file/rmake.rs
new file mode 100644
index 00000000000..26df7e80dfb
--- /dev/null
+++ b/tests/run-make/no-input-file/rmake.rs
@@ -0,0 +1,9 @@
+extern crate run_make_support;
+
+use run_make_support::{diff, rustc};
+
+fn main() {
+    let output = rustc().print("crate-name").run_fail_assert_exit_code(1);
+
+    diff().expected_file("no-input-file.stderr").actual_text("output", output.stderr).run();
+}