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-rw-r--r--compiler/rustc_codegen_llvm/src/consts.rs2
-rw-r--r--compiler/rustc_codegen_llvm/src/llvm/ffi.rs1
-rw-r--r--compiler/rustc_lint/src/impl_trait_overcaptures.rs375
-rw-r--r--compiler/rustc_lint/src/lib.rs1
-rw-r--r--compiler/rustc_middle/src/mir/pretty.rs4
-rw-r--r--compiler/rustc_mir_transform/src/coroutine/by_move_body.rs5
-rw-r--r--compiler/rustc_mir_transform/src/dest_prop.rs113
-rw-r--r--library/core/src/marker.rs15
-rw-r--r--src/librustdoc/html/render/mod.rs86
-rw-r--r--src/librustdoc/html/render/print_item.rs32
-rw-r--r--src/librustdoc/html/render/sidebar.rs47
-rw-r--r--src/librustdoc/html/sources.rs57
-rw-r--r--src/librustdoc/html/static/css/noscript.css4
-rw-r--r--src/librustdoc/html/static/css/rustdoc.css150
-rw-r--r--src/librustdoc/html/static/js/main.js9
-rw-r--r--src/librustdoc/html/static/js/scrape-examples.js7
-rw-r--r--src/librustdoc/html/templates/scraped_source.html33
-rw-r--r--src/librustdoc/html/templates/source.html14
-rw-r--r--src/tools/run-make-support/src/command.rs85
-rw-r--r--src/tools/run-make-support/src/external_deps/llvm.rs7
-rw-r--r--src/tools/run-make-support/src/external_deps/rustc.rs6
-rw-r--r--src/tools/run-make-support/src/external_deps/rustdoc.rs6
-rw-r--r--src/tools/run-make-support/src/lib.rs2
-rw-r--r--tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#0}-{closure#0}.built.after.mir (renamed from tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#0}-{closure#0}.coroutine_by_move.0.panic-abort.mir)8
-rw-r--r--tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#0}-{closure#1}.built.after.mir (renamed from tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#0}-{closure#0}.coroutine_by_move.0.panic-unwind.mir)4
-rw-r--r--tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#0}.coroutine_closure_by_move.0.mir (renamed from tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#0}.coroutine_closure_by_move.0.panic-abort.mir)6
-rw-r--r--tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#0}.coroutine_closure_by_move.0.panic-unwind.mir10
-rw-r--r--tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}-{closure#0}.built.after.mir (renamed from tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}-{closure#0}.coroutine_by_move.0.panic-abort.mir)4
-rw-r--r--tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}-{closure#1}.built.after.mir (renamed from tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}-{closure#0}.coroutine_by_move.0.panic-unwind.mir)4
-rw-r--r--tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}.coroutine_closure_by_move.0.mir (renamed from tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}.coroutine_closure_by_move.0.panic-abort.mir)6
-rw-r--r--tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}.coroutine_closure_by_move.0.panic-unwind.mir10
-rw-r--r--tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}.coroutine_closure_by_ref.0.mir (renamed from tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}.coroutine_closure_by_ref.0.panic-abort.mir)6
-rw-r--r--tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}.coroutine_closure_by_ref.0.panic-unwind.mir10
-rw-r--r--tests/mir-opt/async_closure_shims.rs11
-rw-r--r--tests/run-make/clear-error-blank-output/rmake.rs2
-rw-r--r--tests/run-make/comment-section/rmake.rs2
-rw-r--r--tests/run-make/compile-stdin/rmake.rs2
-rw-r--r--tests/run-make/libtest-junit/rmake.rs2
-rw-r--r--tests/run-make/llvm-ident/rmake.rs2
-rw-r--r--tests/run-make/llvm-outputs/rmake.rs4
-rw-r--r--tests/run-make/no-builtins-attribute/rmake.rs2
-rw-r--r--tests/run-make/pgo-branch-weights/rmake.rs5
-rw-r--r--tests/run-make/pgo-indirect-call-promotion/rmake.rs5
-rw-r--r--tests/run-make/pgo-use/rmake.rs2
-rw-r--r--tests/run-make/separate-link/rmake.rs2
-rw-r--r--tests/run-make/static-pie/rmake.rs2
-rw-r--r--tests/run-make/stdin-rustc/rmake.rs4
-rw-r--r--tests/run-make/stdin-rustdoc/rmake.rs4
-rw-r--r--tests/run-make/sysroot-crates-are-unstable/rmake.rs2
-rw-r--r--tests/run-make/unknown-mod-stdin/rmake.rs2
-rw-r--r--tests/run-make/x86_64-fortanix-unknown-sgx-lvi/rmake.rs12
-rw-r--r--tests/rustdoc-gui/code-example-buttons.goml21
-rw-r--r--tests/rustdoc-gui/docblock-code-block-line-number.goml73
-rw-r--r--tests/rustdoc-gui/scrape-examples-button-focus.goml38
-rw-r--r--tests/rustdoc-gui/scrape-examples-color.goml8
-rw-r--r--tests/rustdoc-gui/scrape-examples-layout.goml87
-rw-r--r--tests/rustdoc-gui/src/theme_css/custom-theme.css2
-rw-r--r--tests/rustdoc/impl-associated-items-order.rs42
-rw-r--r--tests/rustdoc/impl-associated-items-sidebar.rs42
-rw-r--r--tests/ui/impl-trait/precise-capturing/overcaptures-2024-but-fine.rs15
60 files changed, 1074 insertions, 450 deletions
diff --git a/compiler/rustc_codegen_llvm/src/consts.rs b/compiler/rustc_codegen_llvm/src/consts.rs
index b143e28c5f9..d60122fccee 100644
--- a/compiler/rustc_codegen_llvm/src/consts.rs
+++ b/compiler/rustc_codegen_llvm/src/consts.rs
@@ -390,7 +390,7 @@ impl<'ll> CodegenCx<'ll, '_> {
             let val_llty = self.val_ty(v);
 
             let g = self.get_static_inner(def_id, val_llty);
-            let llty = self.val_ty(g);
+            let llty = llvm::LLVMGlobalGetValueType(g);
 
             let g = if val_llty == llty {
                 g
diff --git a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
index 138cc3219aa..3bf4d496408 100644
--- a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
+++ b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
@@ -974,6 +974,7 @@ unsafe extern "C" {
     pub fn LLVMGetAlignment(Global: &Value) -> c_uint;
     pub fn LLVMSetAlignment(Global: &Value, Bytes: c_uint);
     pub fn LLVMSetDLLStorageClass(V: &Value, C: DLLStorageClass);
+    pub fn LLVMGlobalGetValueType(Global: &Value) -> &Type;
 
     // Operations on global variables
     pub fn LLVMIsAGlobalVariable(GlobalVar: &Value) -> Option<&Value>;
diff --git a/compiler/rustc_lint/src/impl_trait_overcaptures.rs b/compiler/rustc_lint/src/impl_trait_overcaptures.rs
index 8824e1dfe50..c43c650a9f9 100644
--- a/compiler/rustc_lint/src/impl_trait_overcaptures.rs
+++ b/compiler/rustc_lint/src/impl_trait_overcaptures.rs
@@ -1,19 +1,29 @@
-use rustc_data_structures::fx::FxIndexSet;
+use std::assert_matches::debug_assert_matches;
+use std::cell::LazyCell;
+
+use rustc_data_structures::fx::{FxHashMap, FxIndexMap, FxIndexSet};
 use rustc_data_structures::unord::UnordSet;
 use rustc_errors::{Applicability, LintDiagnostic};
 use rustc_hir as hir;
 use rustc_hir::def::DefKind;
 use rustc_hir::def_id::{DefId, LocalDefId};
+use rustc_infer::infer::outlives::env::OutlivesEnvironment;
+use rustc_infer::infer::TyCtxtInferExt;
 use rustc_macros::LintDiagnostic;
-use rustc_middle::bug;
 use rustc_middle::middle::resolve_bound_vars::ResolvedArg;
+use rustc_middle::ty::relate::{
+    structurally_relate_consts, structurally_relate_tys, Relate, RelateResult, TypeRelation,
+};
 use rustc_middle::ty::{
     self, Ty, TyCtxt, TypeSuperVisitable, TypeVisitable, TypeVisitableExt, TypeVisitor,
 };
+use rustc_middle::{bug, span_bug};
 use rustc_session::lint::FutureIncompatibilityReason;
 use rustc_session::{declare_lint, declare_lint_pass};
 use rustc_span::edition::Edition;
-use rustc_span::Span;
+use rustc_span::{Span, Symbol};
+use rustc_trait_selection::traits::outlives_bounds::InferCtxtExt;
+use rustc_trait_selection::traits::ObligationCtxt;
 
 use crate::{fluent_generated as fluent, LateContext, LateLintPass};
 
@@ -119,20 +129,41 @@ impl<'tcx> LateLintPass<'tcx> for ImplTraitOvercaptures {
     }
 }
 
+#[derive(PartialEq, Eq, Hash, Debug, Copy, Clone)]
+enum ParamKind {
+    // Early-bound var.
+    Early(Symbol, u32),
+    // Late-bound var on function, not within a binder. We can capture these.
+    Free(DefId, Symbol),
+    // Late-bound var in a binder. We can't capture these yet.
+    Late,
+}
+
 fn check_fn(tcx: TyCtxt<'_>, parent_def_id: LocalDefId) {
     let sig = tcx.fn_sig(parent_def_id).instantiate_identity();
 
-    let mut in_scope_parameters = FxIndexSet::default();
+    let mut in_scope_parameters = FxIndexMap::default();
     // Populate the in_scope_parameters list first with all of the generics in scope
     let mut current_def_id = Some(parent_def_id.to_def_id());
     while let Some(def_id) = current_def_id {
         let generics = tcx.generics_of(def_id);
         for param in &generics.own_params {
-            in_scope_parameters.insert(param.def_id);
+            in_scope_parameters.insert(param.def_id, ParamKind::Early(param.name, param.index));
         }
         current_def_id = generics.parent;
     }
 
+    for bound_var in sig.bound_vars() {
+        let ty::BoundVariableKind::Region(ty::BoundRegionKind::BrNamed(def_id, name)) = bound_var
+        else {
+            span_bug!(tcx.def_span(parent_def_id), "unexpected non-lifetime binder on fn sig");
+        };
+
+        in_scope_parameters.insert(def_id, ParamKind::Free(def_id, name));
+    }
+
+    let sig = tcx.liberate_late_bound_regions(parent_def_id.to_def_id(), sig);
+
     // Then visit the signature to walk through all the binders (incl. the late-bound
     // vars on the function itself, which we need to count too).
     sig.visit_with(&mut VisitOpaqueTypes {
@@ -140,21 +171,45 @@ fn check_fn(tcx: TyCtxt<'_>, parent_def_id: LocalDefId) {
         parent_def_id,
         in_scope_parameters,
         seen: Default::default(),
+        // Lazily compute these two, since they're likely a bit expensive.
+        variances: LazyCell::new(|| {
+            let mut functional_variances = FunctionalVariances {
+                tcx: tcx,
+                variances: FxHashMap::default(),
+                ambient_variance: ty::Covariant,
+                generics: tcx.generics_of(parent_def_id),
+            };
+            functional_variances.relate(sig, sig).unwrap();
+            functional_variances.variances
+        }),
+        outlives_env: LazyCell::new(|| {
+            let param_env = tcx.param_env(parent_def_id);
+            let infcx = tcx.infer_ctxt().build();
+            let ocx = ObligationCtxt::new(&infcx);
+            let assumed_wf_tys = ocx.assumed_wf_types(param_env, parent_def_id).unwrap_or_default();
+            let implied_bounds =
+                infcx.implied_bounds_tys_compat(param_env, parent_def_id, &assumed_wf_tys, false);
+            OutlivesEnvironment::with_bounds(param_env, implied_bounds)
+        }),
     });
 }
 
-struct VisitOpaqueTypes<'tcx> {
+struct VisitOpaqueTypes<'tcx, VarFn, OutlivesFn> {
     tcx: TyCtxt<'tcx>,
     parent_def_id: LocalDefId,
-    in_scope_parameters: FxIndexSet<DefId>,
+    in_scope_parameters: FxIndexMap<DefId, ParamKind>,
+    variances: LazyCell<FxHashMap<DefId, ty::Variance>, VarFn>,
+    outlives_env: LazyCell<OutlivesEnvironment<'tcx>, OutlivesFn>,
     seen: FxIndexSet<LocalDefId>,
 }
 
-impl<'tcx> TypeVisitor<TyCtxt<'tcx>> for VisitOpaqueTypes<'tcx> {
-    fn visit_binder<T: TypeVisitable<TyCtxt<'tcx>>>(
-        &mut self,
-        t: &ty::Binder<'tcx, T>,
-    ) -> Self::Result {
+impl<'tcx, VarFn, OutlivesFn> TypeVisitor<TyCtxt<'tcx>>
+    for VisitOpaqueTypes<'tcx, VarFn, OutlivesFn>
+where
+    VarFn: FnOnce() -> FxHashMap<DefId, ty::Variance>,
+    OutlivesFn: FnOnce() -> OutlivesEnvironment<'tcx>,
+{
+    fn visit_binder<T: TypeVisitable<TyCtxt<'tcx>>>(&mut self, t: &ty::Binder<'tcx, T>) {
         // When we get into a binder, we need to add its own bound vars to the scope.
         let mut added = vec![];
         for arg in t.bound_vars() {
@@ -163,8 +218,8 @@ impl<'tcx> TypeVisitor<TyCtxt<'tcx>> for VisitOpaqueTypes<'tcx> {
                 ty::BoundVariableKind::Region(ty::BoundRegionKind::BrNamed(def_id, ..))
                 | ty::BoundVariableKind::Ty(ty::BoundTyKind::Param(def_id, _)) => {
                     added.push(def_id);
-                    let unique = self.in_scope_parameters.insert(def_id);
-                    assert!(unique);
+                    let unique = self.in_scope_parameters.insert(def_id, ParamKind::Late);
+                    assert_eq!(unique, None);
                 }
                 _ => {
                     self.tcx.dcx().span_delayed_bug(
@@ -184,7 +239,7 @@ impl<'tcx> TypeVisitor<TyCtxt<'tcx>> for VisitOpaqueTypes<'tcx> {
         }
     }
 
-    fn visit_ty(&mut self, t: Ty<'tcx>) -> Self::Result {
+    fn visit_ty(&mut self, t: Ty<'tcx>) {
         if !t.has_aliases() {
             return;
         }
@@ -207,89 +262,126 @@ impl<'tcx> TypeVisitor<TyCtxt<'tcx>> for VisitOpaqueTypes<'tcx> {
             && let hir::OpaqueTyOrigin::FnReturn(parent_def_id) = opaque.origin
             && parent_def_id == self.parent_def_id
         {
-            // Compute the set of args that are captured by the opaque...
-            let mut captured = FxIndexSet::default();
-            let variances = self.tcx.variances_of(opaque_def_id);
-            let mut current_def_id = Some(opaque_def_id.to_def_id());
-            while let Some(def_id) = current_def_id {
-                let generics = self.tcx.generics_of(def_id);
-                for param in &generics.own_params {
-                    // A param is captured if it's invariant.
-                    if variances[param.index as usize] != ty::Invariant {
-                        continue;
-                    }
-                    // We need to turn all `ty::Param`/`ConstKind::Param` and
-                    // `ReEarlyParam`/`ReBound` into def ids.
-                    captured.insert(extract_def_id_from_arg(
-                        self.tcx,
-                        generics,
-                        opaque_ty.args[param.index as usize],
-                    ));
-                }
-                current_def_id = generics.parent;
-            }
-
-            // Compute the set of in scope params that are not captured. Get their spans,
-            // since that's all we really care about them for emitting the diagnostic.
-            let uncaptured_spans: Vec<_> = self
-                .in_scope_parameters
-                .iter()
-                .filter(|def_id| !captured.contains(*def_id))
-                .map(|def_id| self.tcx.def_span(def_id))
-                .collect();
-
             let opaque_span = self.tcx.def_span(opaque_def_id);
             let new_capture_rules =
                 opaque_span.at_least_rust_2024() || self.tcx.features().lifetime_capture_rules_2024;
-
-            // If we have uncaptured args, and if the opaque doesn't already have
-            // `use<>` syntax on it, and we're < edition 2024, then warn the user.
             if !new_capture_rules
                 && !opaque.bounds.iter().any(|bound| matches!(bound, hir::GenericBound::Use(..)))
-                && !uncaptured_spans.is_empty()
             {
-                let suggestion = if let Ok(snippet) =
-                    self.tcx.sess.source_map().span_to_snippet(opaque_span)
-                    && snippet.starts_with("impl ")
-                {
-                    let (lifetimes, others): (Vec<_>, Vec<_>) = captured
-                        .into_iter()
-                        .partition(|def_id| self.tcx.def_kind(*def_id) == DefKind::LifetimeParam);
-                    // Take all lifetime params first, then all others (ty/ct).
-                    let generics: Vec<_> = lifetimes
-                        .into_iter()
-                        .chain(others)
-                        .map(|def_id| self.tcx.item_name(def_id).to_string())
-                        .collect();
-                    // Make sure that we're not trying to name any APITs
-                    if generics.iter().all(|name| !name.starts_with("impl ")) {
-                        Some((
-                            format!(" + use<{}>", generics.join(", ")),
-                            opaque_span.shrink_to_hi(),
-                        ))
+                // Compute the set of args that are captured by the opaque...
+                let mut captured = FxIndexSet::default();
+                let mut captured_regions = FxIndexSet::default();
+                let variances = self.tcx.variances_of(opaque_def_id);
+                let mut current_def_id = Some(opaque_def_id.to_def_id());
+                while let Some(def_id) = current_def_id {
+                    let generics = self.tcx.generics_of(def_id);
+                    for param in &generics.own_params {
+                        // A param is captured if it's invariant.
+                        if variances[param.index as usize] != ty::Invariant {
+                            continue;
+                        }
+
+                        let arg = opaque_ty.args[param.index as usize];
+                        // We need to turn all `ty::Param`/`ConstKind::Param` and
+                        // `ReEarlyParam`/`ReBound` into def ids.
+                        captured.insert(extract_def_id_from_arg(self.tcx, generics, arg));
+
+                        captured_regions.extend(arg.as_region());
+                    }
+                    current_def_id = generics.parent;
+                }
+
+                // Compute the set of in scope params that are not captured.
+                let mut uncaptured_args: FxIndexSet<_> = self
+                    .in_scope_parameters
+                    .iter()
+                    .filter(|&(def_id, _)| !captured.contains(def_id))
+                    .collect();
+                // Remove the set of lifetimes that are in-scope that outlive some other captured
+                // lifetime and are contravariant (i.e. covariant in argument position).
+                uncaptured_args.retain(|&(def_id, kind)| {
+                    let Some(ty::Bivariant | ty::Contravariant) = self.variances.get(def_id) else {
+                        // Keep all covariant/invariant args. Also if variance is `None`,
+                        // then that means it's either not a lifetime, or it didn't show up
+                        // anywhere in the signature.
+                        return true;
+                    };
+                    // We only computed variance of lifetimes...
+                    debug_assert_matches!(self.tcx.def_kind(def_id), DefKind::LifetimeParam);
+                    let uncaptured = match *kind {
+                        ParamKind::Early(name, index) => ty::Region::new_early_param(
+                            self.tcx,
+                            ty::EarlyParamRegion { name, index },
+                        ),
+                        ParamKind::Free(def_id, name) => ty::Region::new_late_param(
+                            self.tcx,
+                            self.parent_def_id.to_def_id(),
+                            ty::BoundRegionKind::BrNamed(def_id, name),
+                        ),
+                        // Totally ignore late bound args from binders.
+                        ParamKind::Late => return true,
+                    };
+                    // Does this region outlive any captured region?
+                    !captured_regions.iter().any(|r| {
+                        self.outlives_env
+                            .free_region_map()
+                            .sub_free_regions(self.tcx, *r, uncaptured)
+                    })
+                });
+
+                // If we have uncaptured args, and if the opaque doesn't already have
+                // `use<>` syntax on it, and we're < edition 2024, then warn the user.
+                if !uncaptured_args.is_empty() {
+                    let suggestion = if let Ok(snippet) =
+                        self.tcx.sess.source_map().span_to_snippet(opaque_span)
+                        && snippet.starts_with("impl ")
+                    {
+                        let (lifetimes, others): (Vec<_>, Vec<_>) =
+                            captured.into_iter().partition(|def_id| {
+                                self.tcx.def_kind(*def_id) == DefKind::LifetimeParam
+                            });
+                        // Take all lifetime params first, then all others (ty/ct).
+                        let generics: Vec<_> = lifetimes
+                            .into_iter()
+                            .chain(others)
+                            .map(|def_id| self.tcx.item_name(def_id).to_string())
+                            .collect();
+                        // Make sure that we're not trying to name any APITs
+                        if generics.iter().all(|name| !name.starts_with("impl ")) {
+                            Some((
+                                format!(" + use<{}>", generics.join(", ")),
+                                opaque_span.shrink_to_hi(),
+                            ))
+                        } else {
+                            None
+                        }
                     } else {
                         None
-                    }
-                } else {
-                    None
-                };
-
-                self.tcx.emit_node_span_lint(
-                    IMPL_TRAIT_OVERCAPTURES,
-                    self.tcx.local_def_id_to_hir_id(opaque_def_id),
-                    opaque_span,
-                    ImplTraitOvercapturesLint {
-                        self_ty: t,
-                        num_captured: uncaptured_spans.len(),
-                        uncaptured_spans,
-                        suggestion,
-                    },
-                );
+                    };
+
+                    let uncaptured_spans: Vec<_> = uncaptured_args
+                        .into_iter()
+                        .map(|(def_id, _)| self.tcx.def_span(def_id))
+                        .collect();
+
+                    self.tcx.emit_node_span_lint(
+                        IMPL_TRAIT_OVERCAPTURES,
+                        self.tcx.local_def_id_to_hir_id(opaque_def_id),
+                        opaque_span,
+                        ImplTraitOvercapturesLint {
+                            self_ty: t,
+                            num_captured: uncaptured_spans.len(),
+                            uncaptured_spans,
+                            suggestion,
+                        },
+                    );
+                }
             }
+
             // Otherwise, if we are edition 2024, have `use<>` syntax, and
             // have no uncaptured args, then we should warn to the user that
             // it's redundant to capture all args explicitly.
-            else if new_capture_rules
+            if new_capture_rules
                 && let Some((captured_args, capturing_span)) =
                     opaque.bounds.iter().find_map(|bound| match *bound {
                         hir::GenericBound::Use(a, s) => Some((a, s)),
@@ -327,7 +419,7 @@ impl<'tcx> TypeVisitor<TyCtxt<'tcx>> for VisitOpaqueTypes<'tcx> {
                 if self
                     .in_scope_parameters
                     .iter()
-                    .all(|def_id| explicitly_captured.contains(def_id))
+                    .all(|(def_id, _)| explicitly_captured.contains(def_id))
                 {
                     self.tcx.emit_node_span_lint(
                         IMPL_TRAIT_REDUNDANT_CAPTURES,
@@ -396,7 +488,11 @@ fn extract_def_id_from_arg<'tcx>(
             ty::ReBound(
                 _,
                 ty::BoundRegion { kind: ty::BoundRegionKind::BrNamed(def_id, ..), .. },
-            ) => def_id,
+            )
+            | ty::ReLateParam(ty::LateParamRegion {
+                scope: _,
+                bound_region: ty::BoundRegionKind::BrNamed(def_id, ..),
+            }) => def_id,
             _ => unreachable!(),
         },
         ty::GenericArgKind::Type(ty) => {
@@ -413,3 +509,106 @@ fn extract_def_id_from_arg<'tcx>(
         }
     }
 }
+
+/// Computes the variances of regions that appear in the type, but considering
+/// late-bound regions too, which don't have their variance computed usually.
+///
+/// Like generalization, this is a unary operation implemented on top of the binary
+/// relation infrastructure, mostly because it's much easier to have the relation
+/// track the variance for you, rather than having to do it yourself.
+struct FunctionalVariances<'tcx> {
+    tcx: TyCtxt<'tcx>,
+    variances: FxHashMap<DefId, ty::Variance>,
+    ambient_variance: ty::Variance,
+    generics: &'tcx ty::Generics,
+}
+
+impl<'tcx> TypeRelation<TyCtxt<'tcx>> for FunctionalVariances<'tcx> {
+    fn cx(&self) -> TyCtxt<'tcx> {
+        self.tcx
+    }
+
+    fn relate_with_variance<T: ty::relate::Relate<TyCtxt<'tcx>>>(
+        &mut self,
+        variance: rustc_type_ir::Variance,
+        _: ty::VarianceDiagInfo<TyCtxt<'tcx>>,
+        a: T,
+        b: T,
+    ) -> RelateResult<'tcx, T> {
+        let old_variance = self.ambient_variance;
+        self.ambient_variance = self.ambient_variance.xform(variance);
+        self.relate(a, b).unwrap();
+        self.ambient_variance = old_variance;
+        Ok(a)
+    }
+
+    fn tys(&mut self, a: Ty<'tcx>, b: Ty<'tcx>) -> RelateResult<'tcx, Ty<'tcx>> {
+        structurally_relate_tys(self, a, b).unwrap();
+        Ok(a)
+    }
+
+    fn regions(
+        &mut self,
+        a: ty::Region<'tcx>,
+        _: ty::Region<'tcx>,
+    ) -> RelateResult<'tcx, ty::Region<'tcx>> {
+        let def_id = match *a {
+            ty::ReEarlyParam(ebr) => self.generics.region_param(ebr, self.tcx).def_id,
+            ty::ReBound(
+                _,
+                ty::BoundRegion { kind: ty::BoundRegionKind::BrNamed(def_id, ..), .. },
+            )
+            | ty::ReLateParam(ty::LateParamRegion {
+                scope: _,
+                bound_region: ty::BoundRegionKind::BrNamed(def_id, ..),
+            }) => def_id,
+            _ => {
+                return Ok(a);
+            }
+        };
+
+        if let Some(variance) = self.variances.get_mut(&def_id) {
+            *variance = unify(*variance, self.ambient_variance);
+        } else {
+            self.variances.insert(def_id, self.ambient_variance);
+        }
+
+        Ok(a)
+    }
+
+    fn consts(
+        &mut self,
+        a: ty::Const<'tcx>,
+        b: ty::Const<'tcx>,
+    ) -> RelateResult<'tcx, ty::Const<'tcx>> {
+        structurally_relate_consts(self, a, b).unwrap();
+        Ok(a)
+    }
+
+    fn binders<T>(
+        &mut self,
+        a: ty::Binder<'tcx, T>,
+        b: ty::Binder<'tcx, T>,
+    ) -> RelateResult<'tcx, ty::Binder<'tcx, T>>
+    where
+        T: Relate<TyCtxt<'tcx>>,
+    {
+        self.relate(a.skip_binder(), b.skip_binder()).unwrap();
+        Ok(a)
+    }
+}
+
+/// What is the variance that satisfies the two variances?
+fn unify(a: ty::Variance, b: ty::Variance) -> ty::Variance {
+    match (a, b) {
+        // Bivariance is lattice bottom.
+        (ty::Bivariant, other) | (other, ty::Bivariant) => other,
+        // Invariant is lattice top.
+        (ty::Invariant, _) | (_, ty::Invariant) => ty::Invariant,
+        // If type is required to be covariant and contravariant, then it's invariant.
+        (ty::Contravariant, ty::Covariant) | (ty::Covariant, ty::Contravariant) => ty::Invariant,
+        // Otherwise, co + co = co, contra + contra = contra.
+        (ty::Contravariant, ty::Contravariant) => ty::Contravariant,
+        (ty::Covariant, ty::Covariant) => ty::Covariant,
+    }
+}
diff --git a/compiler/rustc_lint/src/lib.rs b/compiler/rustc_lint/src/lib.rs
index c5a5c5b30af..bb7de4739fb 100644
--- a/compiler/rustc_lint/src/lib.rs
+++ b/compiler/rustc_lint/src/lib.rs
@@ -30,6 +30,7 @@
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
 #![doc(rust_logo)]
 #![feature(array_windows)]
+#![feature(assert_matches)]
 #![feature(box_patterns)]
 #![feature(control_flow_enum)]
 #![feature(extract_if)]
diff --git a/compiler/rustc_middle/src/mir/pretty.rs b/compiler/rustc_middle/src/mir/pretty.rs
index 9906be60e3e..a98e6943d68 100644
--- a/compiler/rustc_middle/src/mir/pretty.rs
+++ b/compiler/rustc_middle/src/mir/pretty.rs
@@ -612,7 +612,9 @@ fn write_mir_sig(tcx: TyCtxt<'_>, body: &Body<'_>, w: &mut dyn io::Write) -> io:
     let def_id = body.source.def_id();
     let kind = tcx.def_kind(def_id);
     let is_function = match kind {
-        DefKind::Fn | DefKind::AssocFn | DefKind::Ctor(..) => true,
+        DefKind::Fn | DefKind::AssocFn | DefKind::Ctor(..) | DefKind::SyntheticCoroutineBody => {
+            true
+        }
         _ => tcx.is_closure_like(def_id),
     };
     match (kind, body.source.promoted) {
diff --git a/compiler/rustc_mir_transform/src/coroutine/by_move_body.rs b/compiler/rustc_mir_transform/src/coroutine/by_move_body.rs
index ebe8d2eff4f..cf39c136b01 100644
--- a/compiler/rustc_mir_transform/src/coroutine/by_move_body.rs
+++ b/compiler/rustc_mir_transform/src/coroutine/by_move_body.rs
@@ -207,11 +207,12 @@ pub fn coroutine_by_move_body_def_id<'tcx>(
 
     let mut by_move_body = body.clone();
     MakeByMoveBody { tcx, field_remapping, by_move_coroutine_ty }.visit_body(&mut by_move_body);
-    dump_mir(tcx, false, "coroutine_by_move", &0, &by_move_body, |_, _| Ok(()));
 
-    let body_def = tcx.create_def(coroutine_def_id, kw::Empty, DefKind::SyntheticCoroutineBody);
+    // This will always be `{closure#1}`, since the original coroutine is `{closure#0}`.
+    let body_def = tcx.create_def(parent_def_id, kw::Empty, DefKind::SyntheticCoroutineBody);
     by_move_body.source =
         mir::MirSource::from_instance(InstanceKind::Item(body_def.def_id().to_def_id()));
+    dump_mir(tcx, false, "built", &"after", &by_move_body, |_, _| Ok(()));
 
     // Inherited from the by-ref coroutine.
     body_def.codegen_fn_attrs(tcx.codegen_fn_attrs(coroutine_def_id).clone());
diff --git a/compiler/rustc_mir_transform/src/dest_prop.rs b/compiler/rustc_mir_transform/src/dest_prop.rs
index 8940a21d7fa..67bee36b8a5 100644
--- a/compiler/rustc_mir_transform/src/dest_prop.rs
+++ b/compiler/rustc_mir_transform/src/dest_prop.rs
@@ -163,7 +163,8 @@ impl<'tcx> crate::MirPass<'tcx> for DestinationPropagation {
 
     fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
         let def_id = body.source.def_id();
-        let mut allocations = Allocations::default();
+        let mut candidates = Candidates::default();
+        let mut write_info = WriteInfo::default();
         trace!(func = ?tcx.def_path_str(def_id));
 
         let borrowed = rustc_mir_dataflow::impls::borrowed_locals(body);
@@ -191,12 +192,7 @@ impl<'tcx> crate::MirPass<'tcx> for DestinationPropagation {
         loop {
             // PERF: Can we do something smarter than recalculating the candidates and liveness
             // results?
-            let mut candidates = find_candidates(
-                body,
-                &borrowed,
-                &mut allocations.candidates,
-                &mut allocations.candidates_reverse,
-            );
+            candidates.reset_and_find(body, &borrowed);
             trace!(?candidates);
             dest_prop_mir_dump(tcx, body, &points, &live, round_count);
 
@@ -204,7 +200,7 @@ impl<'tcx> crate::MirPass<'tcx> for DestinationPropagation {
                 &mut candidates,
                 &points,
                 &live,
-                &mut allocations.write_info,
+                &mut write_info,
                 body,
             );
 
@@ -253,20 +249,8 @@ impl<'tcx> crate::MirPass<'tcx> for DestinationPropagation {
     }
 }
 
-/// Container for the various allocations that we need.
-///
-/// We store these here and hand out `&mut` access to them, instead of dropping and recreating them
-/// frequently. Everything with a `&'alloc` lifetime points into here.
-#[derive(Default)]
-struct Allocations {
-    candidates: FxIndexMap<Local, Vec<Local>>,
-    candidates_reverse: FxIndexMap<Local, Vec<Local>>,
-    write_info: WriteInfo,
-    // PERF: Do this for `MaybeLiveLocals` allocations too.
-}
-
-#[derive(Debug)]
-struct Candidates<'alloc> {
+#[derive(Debug, Default)]
+struct Candidates {
     /// The set of candidates we are considering in this optimization.
     ///
     /// We will always merge the key into at most one of its values.
@@ -281,11 +265,12 @@ struct Candidates<'alloc> {
     ///
     /// We will still report that we would like to merge `_1` and `_2` in an attempt to allow us to
     /// remove that assignment.
-    c: &'alloc mut FxIndexMap<Local, Vec<Local>>,
+    c: FxIndexMap<Local, Vec<Local>>,
+
     /// A reverse index of the `c` set; if the `c` set contains `a => Place { local: b, proj }`,
     /// then this contains `b => a`.
     // PERF: Possibly these should be `SmallVec`s?
-    reverse: &'alloc mut FxIndexMap<Local, Vec<Local>>,
+    reverse: FxIndexMap<Local, Vec<Local>>,
 }
 
 //////////////////////////////////////////////////////////
@@ -358,19 +343,40 @@ impl<'a, 'tcx> MutVisitor<'tcx> for Merger<'a, 'tcx> {
 //
 // This section enforces bullet point 2
 
-struct FilterInformation<'a, 'body, 'alloc, 'tcx> {
-    body: &'body Body<'tcx>,
+struct FilterInformation<'a, 'tcx> {
+    body: &'a Body<'tcx>,
     points: &'a DenseLocationMap,
     live: &'a SparseIntervalMatrix<Local, PointIndex>,
-    candidates: &'a mut Candidates<'alloc>,
-    write_info: &'alloc mut WriteInfo,
+    candidates: &'a mut Candidates,
+    write_info: &'a mut WriteInfo,
     at: Location,
 }
 
 // We first implement some utility functions which we will expose removing candidates according to
 // different needs. Throughout the liveness filtering, the `candidates` are only ever accessed
 // through these methods, and not directly.
-impl<'alloc> Candidates<'alloc> {
+impl Candidates {
+    /// Collects the candidates for merging.
+    ///
+    /// This is responsible for enforcing the first and third bullet point.
+    fn reset_and_find<'tcx>(&mut self, body: &Body<'tcx>, borrowed: &BitSet<Local>) {
+        self.c.clear();
+        self.reverse.clear();
+        let mut visitor = FindAssignments { body, candidates: &mut self.c, borrowed };
+        visitor.visit_body(body);
+        // Deduplicate candidates.
+        for (_, cands) in self.c.iter_mut() {
+            cands.sort();
+            cands.dedup();
+        }
+        // Generate the reverse map.
+        for (src, cands) in self.c.iter() {
+            for dest in cands.iter().copied() {
+                self.reverse.entry(dest).or_default().push(*src);
+            }
+        }
+    }
+
     /// Just `Vec::retain`, but the condition is inverted and we add debugging output
     fn vec_filter_candidates(
         src: Local,
@@ -445,7 +451,7 @@ enum CandidateFilter {
     Remove,
 }
 
-impl<'a, 'body, 'alloc, 'tcx> FilterInformation<'a, 'body, 'alloc, 'tcx> {
+impl<'a, 'tcx> FilterInformation<'a, 'tcx> {
     /// Filters the set of candidates to remove those that conflict.
     ///
     /// The steps we take are exactly those that are outlined at the top of the file. For each
@@ -463,12 +469,12 @@ impl<'a, 'body, 'alloc, 'tcx> FilterInformation<'a, 'body, 'alloc, 'tcx> {
     /// before the statement/terminator will correctly report locals that are read in the
     /// statement/terminator to be live. We are additionally conservative by treating all written to
     /// locals as also being read from.
-    fn filter_liveness<'b>(
-        candidates: &mut Candidates<'alloc>,
+    fn filter_liveness(
+        candidates: &mut Candidates,
         points: &DenseLocationMap,
         live: &SparseIntervalMatrix<Local, PointIndex>,
-        write_info_alloc: &'alloc mut WriteInfo,
-        body: &'b Body<'tcx>,
+        write_info: &mut WriteInfo,
+        body: &Body<'tcx>,
     ) {
         let mut this = FilterInformation {
             body,
@@ -477,7 +483,7 @@ impl<'a, 'body, 'alloc, 'tcx> FilterInformation<'a, 'body, 'alloc, 'tcx> {
             candidates,
             // We don't actually store anything at this scope, we just keep things here to be able
             // to reuse the allocation.
-            write_info: write_info_alloc,
+            write_info,
             // Doesn't matter what we put here, will be overwritten before being used
             at: Location::START,
         };
@@ -734,40 +740,13 @@ fn places_to_candidate_pair<'tcx>(
     Some((a, b))
 }
 
-/// Collects the candidates for merging
-///
-/// This is responsible for enforcing the first and third bullet point.
-fn find_candidates<'alloc, 'tcx>(
-    body: &Body<'tcx>,
-    borrowed: &BitSet<Local>,
-    candidates: &'alloc mut FxIndexMap<Local, Vec<Local>>,
-    candidates_reverse: &'alloc mut FxIndexMap<Local, Vec<Local>>,
-) -> Candidates<'alloc> {
-    candidates.clear();
-    candidates_reverse.clear();
-    let mut visitor = FindAssignments { body, candidates, borrowed };
-    visitor.visit_body(body);
-    // Deduplicate candidates
-    for (_, cands) in candidates.iter_mut() {
-        cands.sort();
-        cands.dedup();
-    }
-    // Generate the reverse map
-    for (src, cands) in candidates.iter() {
-        for dest in cands.iter().copied() {
-            candidates_reverse.entry(dest).or_default().push(*src);
-        }
-    }
-    Candidates { c: candidates, reverse: candidates_reverse }
-}
-
-struct FindAssignments<'a, 'alloc, 'tcx> {
+struct FindAssignments<'a, 'tcx> {
     body: &'a Body<'tcx>,
-    candidates: &'alloc mut FxIndexMap<Local, Vec<Local>>,
+    candidates: &'a mut FxIndexMap<Local, Vec<Local>>,
     borrowed: &'a BitSet<Local>,
 }
 
-impl<'tcx> Visitor<'tcx> for FindAssignments<'_, '_, 'tcx> {
+impl<'tcx> Visitor<'tcx> for FindAssignments<'_, 'tcx> {
     fn visit_statement(&mut self, statement: &Statement<'tcx>, _: Location) {
         if let StatementKind::Assign(box (
             lhs,
@@ -819,9 +798,9 @@ fn is_local_required(local: Local, body: &Body<'_>) -> bool {
 /////////////////////////////////////////////////////////
 // MIR Dump
 
-fn dest_prop_mir_dump<'body, 'tcx>(
+fn dest_prop_mir_dump<'tcx>(
     tcx: TyCtxt<'tcx>,
-    body: &'body Body<'tcx>,
+    body: &Body<'tcx>,
     points: &DenseLocationMap,
     live: &SparseIntervalMatrix<Local, PointIndex>,
     round: usize,
diff --git a/library/core/src/marker.rs b/library/core/src/marker.rs
index 5654f5aa4b8..d9f197d9510 100644
--- a/library/core/src/marker.rs
+++ b/library/core/src/marker.rs
@@ -288,8 +288,19 @@ marker_impls! {
 /// }
 /// ```
 ///
-/// There is a small difference between the two: the `derive` strategy will also place a `Copy`
-/// bound on type parameters, which isn't always desired.
+/// There is a small difference between the two. The `derive` strategy will also place a `Copy`
+/// bound on type parameters:
+///
+/// ```
+/// #[derive(Clone)]
+/// struct MyStruct<T>(T);
+///
+/// impl<T: Copy> Copy for MyStruct<T> { }
+/// ```
+///
+/// This isn't always desired. For example, shared references (`&T`) can be copied regardless of
+/// whether `T` is `Copy`. Likewise, a generic struct containing markers such as [`PhantomData`]
+/// could potentially be duplicated with a bit-wise copy.
 ///
 /// ## What's the difference between `Copy` and `Clone`?
 ///
diff --git a/src/librustdoc/html/render/mod.rs b/src/librustdoc/html/render/mod.rs
index dc34c7844bf..f67d006116c 100644
--- a/src/librustdoc/html/render/mod.rs
+++ b/src/librustdoc/html/render/mod.rs
@@ -1794,13 +1794,64 @@ fn render_impl(
     let mut default_impl_items = Buffer::empty_from(w);
     let impl_ = i.inner_impl();
 
+    // Impl items are grouped by kinds:
+    //
+    // 1. Constants
+    // 2. Types
+    // 3. Functions
+    //
+    // This order is because you can have associated constants used in associated types (like array
+    // length), and both in associcated functions. So with this order, when reading from top to
+    // bottom, you should see items definitions before they're actually used most of the time.
+    let mut assoc_types = Vec::new();
+    let mut methods = Vec::new();
+
     if !impl_.is_negative_trait_impl() {
         for trait_item in &impl_.items {
+            match *trait_item.kind {
+                clean::MethodItem(..) | clean::TyMethodItem(_) => methods.push(trait_item),
+                clean::TyAssocTypeItem(..) | clean::AssocTypeItem(..) => {
+                    assoc_types.push(trait_item)
+                }
+                clean::TyAssocConstItem(..) | clean::AssocConstItem(_) => {
+                    // We render it directly since they're supposed to come first.
+                    doc_impl_item(
+                        &mut default_impl_items,
+                        &mut impl_items,
+                        cx,
+                        trait_item,
+                        if trait_.is_some() { &i.impl_item } else { parent },
+                        link,
+                        render_mode,
+                        false,
+                        trait_,
+                        rendering_params,
+                    );
+                }
+                _ => {}
+            }
+        }
+
+        for assoc_type in assoc_types {
             doc_impl_item(
                 &mut default_impl_items,
                 &mut impl_items,
                 cx,
-                trait_item,
+                assoc_type,
+                if trait_.is_some() { &i.impl_item } else { parent },
+                link,
+                render_mode,
+                false,
+                trait_,
+                rendering_params,
+            );
+        }
+        for method in methods {
+            doc_impl_item(
+                &mut default_impl_items,
+                &mut impl_items,
+                cx,
+                method,
                 if trait_.is_some() { &i.impl_item } else { parent },
                 link,
                 render_mode,
@@ -2455,28 +2506,6 @@ fn render_call_locations<W: fmt::Write>(mut w: W, cx: &mut Context<'_>, item: &c
         let needs_expansion = line_max - line_min > NUM_VISIBLE_LINES;
         let locations_encoded = serde_json::to_string(&line_ranges).unwrap();
 
-        write!(
-            &mut w,
-            "<div class=\"scraped-example {expanded_cls}\" data-locs=\"{locations}\">\
-                <div class=\"scraped-example-title\">\
-                   {name} (<a href=\"{url}\">{title}</a>)\
-                </div>\
-                <div class=\"code-wrapper\">",
-            expanded_cls = if needs_expansion { "" } else { "expanded" },
-            name = call_data.display_name,
-            url = init_url,
-            title = init_title,
-            // The locations are encoded as a data attribute, so they can be read
-            // later by the JS for interactions.
-            locations = Escape(&locations_encoded)
-        )
-        .unwrap();
-
-        if line_ranges.len() > 1 {
-            w.write_str(r#"<button class="prev">&pr;</button> <button class="next">&sc;</button>"#)
-                .unwrap();
-        }
-
         // Look for the example file in the source map if it exists, otherwise return a dummy span
         let file_span = (|| {
             let source_map = tcx.sess.source_map();
@@ -2507,9 +2536,16 @@ fn render_call_locations<W: fmt::Write>(mut w: W, cx: &mut Context<'_>, item: &c
             cx,
             &cx.root_path(),
             highlight::DecorationInfo(decoration_info),
-            sources::SourceContext::Embedded { offset: line_min, needs_expansion },
+            sources::SourceContext::Embedded(sources::ScrapedInfo {
+                needs_prev_next_buttons: line_ranges.len() > 1,
+                needs_expansion,
+                offset: line_min,
+                name: &call_data.display_name,
+                url: init_url,
+                title: init_title,
+                locations: locations_encoded,
+            }),
         );
-        w.write_str("</div></div>").unwrap();
 
         true
     };
diff --git a/src/librustdoc/html/render/print_item.rs b/src/librustdoc/html/render/print_item.rs
index a0a72d59d12..cda5409a460 100644
--- a/src/librustdoc/html/render/print_item.rs
+++ b/src/librustdoc/html/render/print_item.rs
@@ -843,55 +843,55 @@ fn item_trait(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, t: &clean:
         }
     }
 
-    if !required_types.is_empty() {
+    if !required_consts.is_empty() {
         write_section_heading(
             w,
-            "Required Associated Types",
-            "required-associated-types",
+            "Required Associated Constants",
+            "required-associated-consts",
             None,
             "<div class=\"methods\">",
         );
-        for t in required_types {
+        for t in required_consts {
             trait_item(w, cx, t, it);
         }
         w.write_str("</div>");
     }
-    if !provided_types.is_empty() {
+    if !provided_consts.is_empty() {
         write_section_heading(
             w,
-            "Provided Associated Types",
-            "provided-associated-types",
+            "Provided Associated Constants",
+            "provided-associated-consts",
             None,
             "<div class=\"methods\">",
         );
-        for t in provided_types {
+        for t in provided_consts {
             trait_item(w, cx, t, it);
         }
         w.write_str("</div>");
     }
 
-    if !required_consts.is_empty() {
+    if !required_types.is_empty() {
         write_section_heading(
             w,
-            "Required Associated Constants",
-            "required-associated-consts",
+            "Required Associated Types",
+            "required-associated-types",
             None,
             "<div class=\"methods\">",
         );
-        for t in required_consts {
+        for t in required_types {
             trait_item(w, cx, t, it);
         }
         w.write_str("</div>");
     }
-    if !provided_consts.is_empty() {
+    if !provided_types.is_empty() {
         write_section_heading(
             w,
-            "Provided Associated Constants",
-            "provided-associated-consts",
+            "Provided Associated Types",
+            "provided-associated-types",
             None,
             "<div class=\"methods\">",
         );
-        for t in provided_consts {
+        for t in provided_types {
             trait_item(w, cx, t, it);
         }
         w.write_str("</div>");
diff --git a/src/librustdoc/html/render/sidebar.rs b/src/librustdoc/html/render/sidebar.rs
index c75c28ef0a3..06cc57b2a55 100644
--- a/src/librustdoc/html/render/sidebar.rs
+++ b/src/librustdoc/html/render/sidebar.rs
@@ -302,10 +302,10 @@ fn sidebar_trait<'a>(
 
     blocks.extend(
         [
-            ("required-associated-types", "Required Associated Types", req_assoc),
-            ("provided-associated-types", "Provided Associated Types", prov_assoc),
             ("required-associated-consts", "Required Associated Constants", req_assoc_const),
             ("provided-associated-consts", "Provided Associated Constants", prov_assoc_const),
+            ("required-associated-types", "Required Associated Types", req_assoc),
+            ("provided-associated-types", "Provided Associated Types", prov_assoc),
             ("required-methods", "Required Methods", req_method),
             ("provided-methods", "Provided Methods", prov_method),
             ("foreign-impls", "Implementations on Foreign Types", foreign_impls),
@@ -394,6 +394,7 @@ fn sidebar_assoc_items<'a>(
     let cache = cx.cache();
 
     let mut assoc_consts = Vec::new();
+    let mut assoc_types = Vec::new();
     let mut methods = Vec::new();
     if let Some(v) = cache.impls.get(&did) {
         let mut used_links = FxHashSet::default();
@@ -401,22 +402,14 @@ fn sidebar_assoc_items<'a>(
 
         {
             let used_links_bor = &mut used_links;
-            assoc_consts.extend(
-                v.iter()
-                    .filter(|i| i.inner_impl().trait_.is_none())
-                    .flat_map(|i| get_associated_constants(i.inner_impl(), used_links_bor)),
-            );
+            for impl_ in v.iter().map(|i| i.inner_impl()).filter(|i| i.trait_.is_none()) {
+                assoc_consts.extend(get_associated_constants(impl_, used_links_bor));
+                assoc_types.extend(get_associated_types(impl_, used_links_bor));
+                methods.extend(get_methods(impl_, false, used_links_bor, false, cx.tcx()));
+            }
             // We want links' order to be reproducible so we don't use unstable sort.
             assoc_consts.sort();
-
-            #[rustfmt::skip] // rustfmt makes the pipeline less readable
-            methods.extend(
-                v.iter()
-                    .filter(|i| i.inner_impl().trait_.is_none())
-                    .flat_map(|i| get_methods(i.inner_impl(), false, used_links_bor, false, cx.tcx())),
-            );
-
-            // We want links' order to be reproducible so we don't use unstable sort.
+            assoc_types.sort();
             methods.sort();
         }
 
@@ -426,6 +419,11 @@ fn sidebar_assoc_items<'a>(
                 "associatedconstant",
                 assoc_consts,
             ),
+            LinkBlock::new(
+                Link::new("implementations", "Associated Types"),
+                "associatedtype",
+                assoc_types,
+            ),
             LinkBlock::new(Link::new("implementations", "Methods"), "method", methods),
         ];
 
@@ -452,6 +450,7 @@ fn sidebar_assoc_items<'a>(
                 &mut blocks,
             );
         }
+
         links.append(&mut blocks);
     }
 }
@@ -715,3 +714,19 @@ fn get_associated_constants<'a>(
         })
         .collect::<Vec<_>>()
 }
+
+fn get_associated_types<'a>(
+    i: &'a clean::Impl,
+    used_links: &mut FxHashSet<String>,
+) -> Vec<Link<'a>> {
+    i.items
+        .iter()
+        .filter_map(|item| match item.name {
+            Some(ref name) if !name.is_empty() && item.is_associated_type() => Some(Link::new(
+                get_next_url(used_links, format!("{typ}.{name}", typ = ItemType::AssocType)),
+                name.as_str(),
+            )),
+            _ => None,
+        })
+        .collect::<Vec<_>>()
+}
diff --git a/src/librustdoc/html/sources.rs b/src/librustdoc/html/sources.rs
index ae65dd76b5f..551bb56685c 100644
--- a/src/librustdoc/html/sources.rs
+++ b/src/librustdoc/html/sources.rs
@@ -290,9 +290,34 @@ where
     }
 }
 
-pub(crate) enum SourceContext {
+pub(crate) struct ScrapedInfo<'a> {
+    pub(crate) offset: usize,
+    pub(crate) needs_prev_next_buttons: bool,
+    pub(crate) name: &'a str,
+    pub(crate) url: &'a str,
+    pub(crate) title: &'a str,
+    pub(crate) locations: String,
+    pub(crate) needs_expansion: bool,
+}
+
+#[derive(Template)]
+#[template(path = "scraped_source.html")]
+struct ScrapedSource<'a, Code: std::fmt::Display> {
+    info: ScrapedInfo<'a>,
+    lines: RangeInclusive<usize>,
+    code_html: Code,
+}
+
+#[derive(Template)]
+#[template(path = "source.html")]
+struct Source<Code: std::fmt::Display> {
+    lines: RangeInclusive<usize>,
+    code_html: Code,
+}
+
+pub(crate) enum SourceContext<'a> {
     Standalone,
-    Embedded { offset: usize, needs_expansion: bool },
+    Embedded(ScrapedInfo<'a>),
 }
 
 /// Wrapper struct to render the source code of a file. This will do things like
@@ -304,23 +329,8 @@ pub(crate) fn print_src(
     context: &Context<'_>,
     root_path: &str,
     decoration_info: highlight::DecorationInfo,
-    source_context: SourceContext,
+    source_context: SourceContext<'_>,
 ) {
-    #[derive(Template)]
-    #[template(path = "source.html")]
-    struct Source<Code: std::fmt::Display> {
-        embedded: bool,
-        needs_expansion: bool,
-        lines: RangeInclusive<usize>,
-        code_html: Code,
-    }
-    let lines = s.lines().count();
-    let (embedded, needs_expansion, lines) = match source_context {
-        SourceContext::Standalone => (false, false, 1..=lines),
-        SourceContext::Embedded { offset, needs_expansion } => {
-            (true, needs_expansion, (1 + offset)..=(lines + offset))
-        }
-    };
     let current_href = context
         .href_from_span(clean::Span::new(file_span), false)
         .expect("only local crates should have sources emitted");
@@ -333,5 +343,14 @@ pub(crate) fn print_src(
         );
         Ok(())
     });
-    Source { embedded, needs_expansion, lines, code_html: code }.render_into(&mut writer).unwrap();
+    let lines = s.lines().count();
+    match source_context {
+        SourceContext::Standalone => {
+            Source { lines: (1..=lines), code_html: code }.render_into(&mut writer).unwrap()
+        }
+        SourceContext::Embedded(info) => {
+            let lines = (1 + info.offset)..=(lines + info.offset);
+            ScrapedSource { info, lines, code_html: code }.render_into(&mut writer).unwrap();
+        }
+    };
 }
diff --git a/src/librustdoc/html/static/css/noscript.css b/src/librustdoc/html/static/css/noscript.css
index 86e8edad703..e62b16267f1 100644
--- a/src/librustdoc/html/static/css/noscript.css
+++ b/src/librustdoc/html/static/css/noscript.css
@@ -59,6 +59,8 @@ nav.sub {
 	--copy-path-button-color: #999;
 	--copy-path-img-filter: invert(50%);
 	--copy-path-img-hover-filter: invert(35%);
+	--code-example-button-color: #7f7f7f;
+	--code-example-button-hover-color: #595959;
 	--codeblock-error-hover-color: rgb(255, 0, 0);
 	--codeblock-error-color: rgba(255, 0, 0, .5);
 	--codeblock-ignore-hover-color: rgb(255, 142, 0);
@@ -162,6 +164,8 @@ nav.sub {
 		--copy-path-button-color: #999;
 		--copy-path-img-filter: invert(50%);
 		--copy-path-img-hover-filter: invert(65%);
+		--code-example-button-color: #7f7f7f;
+		--code-example-button-hover-color: #a5a5a5;
 		--codeblock-error-hover-color: rgb(255, 0, 0);
 		--codeblock-error-color: rgba(255, 0, 0, .5);
 		--codeblock-ignore-hover-color: rgb(255, 142, 0);
diff --git a/src/librustdoc/html/static/css/rustdoc.css b/src/librustdoc/html/static/css/rustdoc.css
index 271de1b1ccf..38154dee3e2 100644
--- a/src/librustdoc/html/static/css/rustdoc.css
+++ b/src/librustdoc/html/static/css/rustdoc.css
@@ -378,7 +378,7 @@ pre.item-decl {
 .src .content pre {
 	padding: 20px;
 }
-.rustdoc.src .example-wrap pre.src-line-numbers  {
+.rustdoc.src .example-wrap .src-line-numbers  {
 	padding: 20px 0 20px 4px;
 }
 
@@ -757,10 +757,32 @@ ul.block, .block li, .block ul {
 	margin-bottom: 10px;
 }
 
-.rustdoc .example-wrap > pre {
+.rustdoc .example-wrap > pre,
+.rustdoc .scraped-example .src-line-numbers,
+.rustdoc .scraped-example .src-line-numbers > pre {
 	border-radius: 6px;
 }
 
+/*
+If the code example line numbers are displayed, there will be a weird radius in the middle from
+both the code example and the line numbers, so we need to remove the radius in this case.
+*/
+.rustdoc .example-wrap > .example-line-numbers,
+.rustdoc .scraped-example .src-line-numbers,
+.rustdoc .scraped-example .src-line-numbers > pre {
+	border-top-right-radius: 0;
+	border-bottom-right-radius: 0;
+}
+.rustdoc .example-wrap > .example-line-numbers + pre,
+.rustdoc .scraped-example .rust {
+	border-top-left-radius: 0;
+	border-bottom-left-radius: 0;
+}
+
+.rustdoc .scraped-example {
+	position: relative;
+}
+
 /* For the last child of a div, the margin will be taken care of
 	by the margin-top of the next item. */
 .rustdoc .example-wrap:last-child {
@@ -772,15 +794,36 @@ ul.block, .block li, .block ul {
 	flex-grow: 1;
 }
 
-.rustdoc:not(.src) .example-wrap pre {
+.scraped-example:not(.expanded) .example-wrap {
+	/* scrape-examples.js has a constant DEFAULT_MAX_LINES (call it N) for the number
+	 * of lines shown in the un-expanded example code viewer. This pre needs to have
+	 * a max-height equal to line-height * N. The line-height is currently 1.5em,
+	 * and we include additional 10px for padding. */
+	max-height: calc(1.5em * 5 + 10px);
+}
+
+.rustdoc:not(.src) .scraped-example:not(.expanded) .src-line-numbers,
+.rustdoc:not(.src) .scraped-example:not(.expanded) .src-line-numbers > pre,
+.rustdoc:not(.src) .scraped-example:not(.expanded) pre.rust {
+	padding-bottom: 0;
+	/* See above comment, should be the same max-height. */
 	overflow: auto hidden;
 }
+.rustdoc:not(.src) .scraped-example .src-line-numbers {
+	padding-top: 0;
+}
+.rustdoc:not(.src) .scraped-example.expanded .src-line-numbers {
+	padding-bottom: 0;
+}
+
+.rustdoc:not(.src) .example-wrap pre {
+	overflow: auto;
+}
 
 .rustdoc .example-wrap pre.example-line-numbers,
-.rustdoc .example-wrap pre.src-line-numbers {
-	flex-grow: 0;
+.rustdoc .example-wrap .src-line-numbers {
 	min-width: fit-content; /* prevent collapsing into nothing in truncated scraped examples */
-	overflow: initial;
+	flex-grow: 0;
 	text-align: right;
 	-webkit-user-select: none;
 	user-select: none;
@@ -788,7 +831,7 @@ ul.block, .block li, .block ul {
 	color: var(--src-line-numbers-span-color);
 }
 
-.rustdoc .example-wrap pre.src-line-numbers {
+.rustdoc .scraped-example .src-line-numbers {
 	padding: 14px 0;
 }
 .src-line-numbers a, .src-line-numbers span {
@@ -1500,17 +1543,23 @@ instead, we check that it's not a "finger" cursor.
 .example-wrap .button-holder.keep-visible {
 	visibility: visible;
 }
-.example-wrap .button-holder .copy-button, .example-wrap .test-arrow {
+.example-wrap .button-holder > * {
 	background: var(--main-background-color);
 	cursor: pointer;
 	border-radius: var(--button-border-radius);
 	height: var(--copy-path-height);
 	width: var(--copy-path-width);
+	border: 0;
+	color: var(--code-example-button-color);
 }
-.example-wrap .button-holder .copy-button {
+.example-wrap .button-holder > *:hover {
+	color: var(--code-example-button-hover-color);
+}
+.example-wrap .button-holder > *:not(:first-child) {
 	margin-left: var(--button-left-margin);
+}
+.example-wrap .button-holder .copy-button {
 	padding: 2px 0 0 4px;
-	border: 0;
 }
 .example-wrap .button-holder .copy-button::before,
 .example-wrap .test-arrow::before {
@@ -2254,6 +2303,7 @@ in src-script.js and main.js
 	}
 }
 
+
 /* Should have min-width: (N + 1)px where N is the mobile breakpoint above. */
 @media (min-width: 701px) {
 	/* Places file-link for a scraped example on top of the example to save space.
@@ -2356,99 +2406,41 @@ in src-script.js and main.js
 	color: var(--scrape-example-help-hover-color);
 }
 
-.scraped-example {
-	/* So .scraped-example-title can be positioned absolutely */
-	position: relative;
-}
-
-.scraped-example .code-wrapper {
-	position: relative;
-	display: flex;
-	flex-direction: row;
-	flex-wrap: wrap;
-	width: 100%;
-}
-
-.scraped-example:not(.expanded) .code-wrapper {
-	/* scrape-examples.js has a constant DEFAULT_MAX_LINES (call it N) for the number
-	 * of lines shown in the un-expanded example code viewer. This pre needs to have
-	 * a max-height equal to line-height * N. The line-height is currently 1.5em,
-	 * and we include additional 10px for padding. */
-	 max-height: calc(1.5em * 5 + 10px);
-}
-
-.scraped-example:not(.expanded) .code-wrapper pre {
-	overflow-y: hidden;
-	padding-bottom: 0;
-	/* See above comment, should be the same max-height. */
-	max-height: calc(1.5em * 5 + 10px);
-}
-
-.more-scraped-examples .scraped-example:not(.expanded) .code-wrapper,
-.more-scraped-examples .scraped-example:not(.expanded) .code-wrapper pre {
-	/* See above comment, except this height is based on HIDDEN_MAX_LINES. */
-	max-height: calc(1.5em * 10 + 10px);
-}
-
-.scraped-example .code-wrapper .next,
-.scraped-example .code-wrapper .prev,
-.scraped-example .code-wrapper .expand {
-	color: var(--main-color);
-	position: absolute;
-	top: 0.25em;
-	z-index: 1;
-	padding: 0;
-	background: none;
-	border: none;
-	/* iOS button gradient: https://stackoverflow.com/q/5438567 */
-	-webkit-appearance: none;
-	opacity: 1;
-}
-.scraped-example .code-wrapper .prev {
-	right: 2.25em;
-}
-.scraped-example .code-wrapper .next {
-	right: 1.25em;
-}
-.scraped-example .code-wrapper .expand {
-	right: 0.25em;
-}
-
-.scraped-example:not(.expanded) .code-wrapper::before,
-.scraped-example:not(.expanded) .code-wrapper::after {
+.scraped-example:not(.expanded) .example-wrap::before,
+.scraped-example:not(.expanded) .example-wrap::after {
 	content: " ";
 	width: 100%;
 	height: 5px;
 	position: absolute;
 	z-index: 1;
 }
-.scraped-example:not(.expanded) .code-wrapper::before {
+.scraped-example:not(.expanded) .example-wrap::before {
 	top: 0;
 	background: linear-gradient(to bottom,
 		var(--scrape-example-code-wrapper-background-start),
 		var(--scrape-example-code-wrapper-background-end));
 }
-.scraped-example:not(.expanded) .code-wrapper::after {
+.scraped-example:not(.expanded) .example-wrap::after {
 	bottom: 0;
 	background: linear-gradient(to top,
 		var(--scrape-example-code-wrapper-background-start),
 		var(--scrape-example-code-wrapper-background-end));
 }
 
-.scraped-example .code-wrapper .example-wrap {
+.scraped-example:not(.expanded) {
 	width: 100%;
 	overflow-y: hidden;
 	margin-bottom: 0;
 }
 
-.scraped-example:not(.expanded) .code-wrapper .example-wrap {
+.scraped-example:not(.expanded) {
 	overflow-x: hidden;
 }
 
-.scraped-example .example-wrap .rust span.highlight {
+.scraped-example .rust span.highlight {
 	background: var(--scrape-example-code-line-highlight);
 }
-.scraped-example .example-wrap .rust span.highlight.focus {
+.scraped-example .rust span.highlight.focus {
 	background: var(--scrape-example-code-line-highlight-focus);
 }
 
@@ -2542,6 +2534,8 @@ by default.
 	--copy-path-button-color: #999;
 	--copy-path-img-filter: invert(50%);
 	--copy-path-img-hover-filter: invert(35%);
+	--code-example-button-color: #7f7f7f;
+	--code-example-button-hover-color: #595959;
 	--codeblock-error-hover-color: rgb(255, 0, 0);
 	--codeblock-error-color: rgba(255, 0, 0, .5);
 	--codeblock-ignore-hover-color: rgb(255, 142, 0);
@@ -2644,6 +2638,8 @@ by default.
 	--copy-path-button-color: #999;
 	--copy-path-img-filter: invert(50%);
 	--copy-path-img-hover-filter: invert(65%);
+	--code-example-button-color: #7f7f7f;
+	--code-example-button-hover-color: #a5a5a5;
 	--codeblock-error-hover-color: rgb(255, 0, 0);
 	--codeblock-error-color: rgba(255, 0, 0, .5);
 	--codeblock-ignore-hover-color: rgb(255, 142, 0);
@@ -2753,6 +2749,8 @@ Original by Dempfi (https://github.com/dempfi/ayu)
 	--copy-path-button-color: #fff;
 	--copy-path-img-filter: invert(70%);
 	--copy-path-img-hover-filter: invert(100%);
+	--code-example-button-color: #b2b2b2;
+	--code-example-button-hover-color: #fff;
 	--codeblock-error-hover-color: rgb(255, 0, 0);
 	--codeblock-error-color: rgba(255, 0, 0, .5);
 	--codeblock-ignore-hover-color: rgb(255, 142, 0);
diff --git a/src/librustdoc/html/static/js/main.js b/src/librustdoc/html/static/js/main.js
index 0291b6ed6f5..858753a1917 100644
--- a/src/librustdoc/html/static/js/main.js
+++ b/src/librustdoc/html/static/js/main.js
@@ -1855,8 +1855,13 @@ href="https://doc.rust-lang.org/${channel}/rustdoc/read-documentation/search.htm
         // Since the button will be added, no need to keep this listener around.
         elem.removeEventListener("mouseover", addCopyButton);
 
-        const parent = document.createElement("div");
-        parent.className = "button-holder";
+        // If this is a scrapped example, there will already be a "button-holder" element.
+        let parent = elem.querySelector(".button-holder");
+        if (!parent) {
+            parent = document.createElement("div");
+            parent.className = "button-holder";
+        }
+
         const runButton = elem.querySelector(".test-arrow");
         if (runButton !== null) {
             // If there is a run button, we move it into the same div.
diff --git a/src/librustdoc/html/static/js/scrape-examples.js b/src/librustdoc/html/static/js/scrape-examples.js
index 7a3a9c5f340..06e42814d33 100644
--- a/src/librustdoc/html/static/js/scrape-examples.js
+++ b/src/librustdoc/html/static/js/scrape-examples.js
@@ -13,7 +13,7 @@
 
     // Scroll code block to the given code location
     function scrollToLoc(elt, loc, isHidden) {
-        const lines = elt.querySelector(".src-line-numbers");
+        const lines = elt.querySelector(".src-line-numbers > pre");
         let scrollOffset;
 
         // If the block is greater than the size of the viewer,
@@ -24,8 +24,7 @@
             const line = Math.max(0, loc[0] - 1);
             scrollOffset = lines.children[line].offsetTop;
         } else {
-            const wrapper = elt.querySelector(".code-wrapper");
-            const halfHeight = wrapper.offsetHeight / 2;
+            const halfHeight = elt.offsetHeight / 2;
             const offsetTop = lines.children[loc[0]].offsetTop;
             const lastLine = lines.children[loc[1]];
             const offsetBot = lastLine.offsetTop + lastLine.offsetHeight;
@@ -33,7 +32,7 @@
             scrollOffset = offsetMid - halfHeight;
         }
 
-        lines.scrollTo(0, scrollOffset);
+        lines.parentElement.scrollTo(0, scrollOffset);
         elt.querySelector(".rust").scrollTo(0, scrollOffset);
     }
 
diff --git a/src/librustdoc/html/templates/scraped_source.html b/src/librustdoc/html/templates/scraped_source.html
new file mode 100644
index 00000000000..e1fc2e69378
--- /dev/null
+++ b/src/librustdoc/html/templates/scraped_source.html
@@ -0,0 +1,33 @@
+<div class="scraped-example{% if !info.needs_expansion +%} expanded{% endif %}" data-locs="{{info.locations}}"> {# #}
+    <div class="scraped-example-title">
+       {{info.name +}} (<a href="{{info.url}}">{{info.title}}</a>) {# #}
+    </div>
+    <div class="example-wrap"> {# #}
+        {# https://developers.google.com/search/docs/crawling-indexing/robots-meta-tag#data-nosnippet-attr
+           Do not show "1 2 3 4 5 ..." in web search results. #}
+        <div class="src-line-numbers" data-nosnippet> {# #}
+            <pre>
+                {% for line in lines.clone() %}
+                    {# ~#}
+                    <span>{{line|safe}}</span>
+                {% endfor %}
+            </pre> {# #}
+        </div> {# #}
+        <pre class="rust"> {# #}
+            <code>
+                {{code_html|safe}}
+            </code> {# #}
+        </pre> {# #}
+        {% if info.needs_prev_next_buttons || info.needs_expansion %}
+            <div class="button-holder">
+                {% if info.needs_prev_next_buttons %}
+                    <button class="prev">&pr;</button> {# #}
+                    <button class="next">&sc;</button>
+                {% endif %}
+                {% if info.needs_expansion %}
+                    <button class="expand">&varr;</button>
+                {% endif %}
+            </div>
+        {% endif %}
+    </div> {# #}
+</div> {# #}
diff --git a/src/librustdoc/html/templates/source.html b/src/librustdoc/html/templates/source.html
index 42d01277db2..60a47f1b5de 100644
--- a/src/librustdoc/html/templates/source.html
+++ b/src/librustdoc/html/templates/source.html
@@ -1,21 +1,15 @@
-<div class="example-wrap"> {# #}
+<div class="example-wrap">
     {# https://developers.google.com/search/docs/crawling-indexing/robots-meta-tag#data-nosnippet-attr
        Do not show "1 2 3 4 5 ..." in web search results. #}
     <div data-nosnippet><pre class="src-line-numbers">
         {% for line in lines.clone() %}
-            {% if embedded %}
-                <span>{{line|safe}}</span>
-            {%~ else %}
-                <a href="#{{line|safe}}" id="{{line|safe}}">{{line|safe}}</a>
-            {%~ endif %}
+            {# ~#}
+            <a href="#{{line|safe}}" id="{{line|safe}}">{{line|safe}}</a>
         {% endfor %}
     </pre></div> {# #}
     <pre class="rust"> {# #}
         <code>
-            {% if needs_expansion %}
-                <button class="expand">&varr;</button>
-            {% endif %}
             {{code_html|safe}}
         </code> {# #}
     </pre> {# #}
-</div>
+</div> {# #}
diff --git a/src/tools/run-make-support/src/command.rs b/src/tools/run-make-support/src/command.rs
index a0b96e25a0c..6b58173b343 100644
--- a/src/tools/run-make-support/src/command.rs
+++ b/src/tools/run-make-support/src/command.rs
@@ -15,7 +15,7 @@ use crate::{
 /// This is a custom command wrapper that simplifies working with commands and makes it easier to
 /// ensure that we check the exit status of executed processes.
 ///
-/// # A [`Command`] must be executed
+/// # A [`Command`] must be executed exactly once
 ///
 /// A [`Command`] is armed by a [`DropBomb`] on construction to enforce that it will be executed. If
 /// a [`Command`] is constructed but never executed, the drop bomb will explode and cause the test
@@ -23,26 +23,73 @@ use crate::{
 /// containing constructed but never executed commands is dangerous because it can give a false
 /// sense of confidence.
 ///
+/// Each [`Command`] invocation can also only be executed once, because we want to enforce
+/// `std{in,out,err}` config via [`std::process::Stdio`] but [`std::process::Stdio`] is not
+/// cloneable.
+///
+/// In this sense, [`Command`] exhibits linear type semantics but enforced at run-time.
+///
 /// [`run`]: Self::run
 /// [`run_fail`]: Self::run_fail
 /// [`run_unchecked`]: Self::run_unchecked
 #[derive(Debug)]
 pub struct Command {
     cmd: StdCommand,
-    stdin: Option<Box<[u8]>>,
+    // Convience for providing a quick stdin buffer.
+    stdin_buf: Option<Box<[u8]>>,
+
+    // Configurations for child process's std{in,out,err} handles.
+    stdin: Option<Stdio>,
+    stdout: Option<Stdio>,
+    stderr: Option<Stdio>,
+
+    // Emulate linear type semantics.
     drop_bomb: DropBomb,
+    already_executed: bool,
 }
 
 impl Command {
     #[track_caller]
     pub fn new<P: AsRef<OsStr>>(program: P) -> Self {
         let program = program.as_ref();
-        Self { cmd: StdCommand::new(program), stdin: None, drop_bomb: DropBomb::arm(program) }
+        Self {
+            cmd: StdCommand::new(program),
+            stdin_buf: None,
+            drop_bomb: DropBomb::arm(program),
+            stdin: None,
+            stdout: None,
+            stderr: None,
+            already_executed: false,
+        }
     }
 
-    /// Specify a stdin input
-    pub fn stdin<I: AsRef<[u8]>>(&mut self, input: I) -> &mut Self {
-        self.stdin = Some(input.as_ref().to_vec().into_boxed_slice());
+    /// Specify a stdin input buffer. This is a convenience helper,
+    pub fn stdin_buf<I: AsRef<[u8]>>(&mut self, input: I) -> &mut Self {
+        self.stdin_buf = Some(input.as_ref().to_vec().into_boxed_slice());
+        self
+    }
+
+    /// Configuration for the child process’s standard input (stdin) handle.
+    ///
+    /// See [`std::process::Command::stdin`].
+    pub fn stdin<T: Into<Stdio>>(&mut self, cfg: T) -> &mut Self {
+        self.stdin = Some(cfg.into());
+        self
+    }
+
+    /// Configuration for the child process’s standard output (stdout) handle.
+    ///
+    /// See [`std::process::Command::stdout`].
+    pub fn stdout<T: Into<Stdio>>(&mut self, cfg: T) -> &mut Self {
+        self.stdout = Some(cfg.into());
+        self
+    }
+
+    /// Configuration for the child process’s standard error (stderr) handle.
+    ///
+    /// See [`std::process::Command::stderr`].
+    pub fn stderr<T: Into<Stdio>>(&mut self, cfg: T) -> &mut Self {
+        self.stderr = Some(cfg.into());
         self
     }
 
@@ -105,6 +152,8 @@ impl Command {
     }
 
     /// Run the constructed command and assert that it is successfully run.
+    ///
+    /// By default, std{in,out,err} are [`Stdio::piped()`].
     #[track_caller]
     pub fn run(&mut self) -> CompletedProcess {
         let output = self.command_output();
@@ -115,6 +164,8 @@ impl Command {
     }
 
     /// Run the constructed command and assert that it does not successfully run.
+    ///
+    /// By default, std{in,out,err} are [`Stdio::piped()`].
     #[track_caller]
     pub fn run_fail(&mut self) -> CompletedProcess {
         let output = self.command_output();
@@ -124,10 +175,10 @@ impl Command {
         output
     }
 
-    /// Run the command but do not check its exit status.
-    /// Only use if you explicitly don't care about the exit status.
-    /// Prefer to use [`Self::run`] and [`Self::run_fail`]
-    /// whenever possible.
+    /// Run the command but do not check its exit status. Only use if you explicitly don't care
+    /// about the exit status.
+    ///
+    /// Prefer to use [`Self::run`] and [`Self::run_fail`] whenever possible.
     #[track_caller]
     pub fn run_unchecked(&mut self) -> CompletedProcess {
         self.command_output()
@@ -135,13 +186,19 @@ impl Command {
 
     #[track_caller]
     fn command_output(&mut self) -> CompletedProcess {
+        if self.already_executed {
+            panic!("command was already executed");
+        } else {
+            self.already_executed = true;
+        }
+
         self.drop_bomb.defuse();
         // let's make sure we piped all the input and outputs
-        self.cmd.stdin(Stdio::piped());
-        self.cmd.stdout(Stdio::piped());
-        self.cmd.stderr(Stdio::piped());
+        self.cmd.stdin(self.stdin.take().unwrap_or(Stdio::piped()));
+        self.cmd.stdout(self.stdout.take().unwrap_or(Stdio::piped()));
+        self.cmd.stderr(self.stderr.take().unwrap_or(Stdio::piped()));
 
-        let output = if let Some(input) = &self.stdin {
+        let output = if let Some(input) = &self.stdin_buf {
             let mut child = self.cmd.spawn().unwrap();
 
             {
diff --git a/src/tools/run-make-support/src/external_deps/llvm.rs b/src/tools/run-make-support/src/external_deps/llvm.rs
index e9315856cd7..2522c4aeb93 100644
--- a/src/tools/run-make-support/src/external_deps/llvm.rs
+++ b/src/tools/run-make-support/src/external_deps/llvm.rs
@@ -227,9 +227,10 @@ impl LlvmFilecheck {
         Self { cmd }
     }
 
-    /// Pipe a read file into standard input containing patterns that will be matched against the .patterns(path) call.
-    pub fn stdin<I: AsRef<[u8]>>(&mut self, input: I) -> &mut Self {
-        self.cmd.stdin(input);
+    /// Provide a buffer representing standard input containing patterns that will be matched
+    /// against the `.patterns(path)` call.
+    pub fn stdin_buf<I: AsRef<[u8]>>(&mut self, input: I) -> &mut Self {
+        self.cmd.stdin_buf(input);
         self
     }
 
diff --git a/src/tools/run-make-support/src/external_deps/rustc.rs b/src/tools/run-make-support/src/external_deps/rustc.rs
index cece58d2956..f60ea972839 100644
--- a/src/tools/run-make-support/src/external_deps/rustc.rs
+++ b/src/tools/run-make-support/src/external_deps/rustc.rs
@@ -291,9 +291,9 @@ impl Rustc {
         self
     }
 
-    /// Specify a stdin input
-    pub fn stdin<I: AsRef<[u8]>>(&mut self, input: I) -> &mut Self {
-        self.cmd.stdin(input);
+    /// Specify a stdin input buffer.
+    pub fn stdin_buf<I: AsRef<[u8]>>(&mut self, input: I) -> &mut Self {
+        self.cmd.stdin_buf(input);
         self
     }
 
diff --git a/src/tools/run-make-support/src/external_deps/rustdoc.rs b/src/tools/run-make-support/src/external_deps/rustdoc.rs
index 96b1c719e2e..df5e5d8a2e8 100644
--- a/src/tools/run-make-support/src/external_deps/rustdoc.rs
+++ b/src/tools/run-make-support/src/external_deps/rustdoc.rs
@@ -85,9 +85,9 @@ impl Rustdoc {
         self
     }
 
-    /// Specify a stdin input
-    pub fn stdin<I: AsRef<[u8]>>(&mut self, input: I) -> &mut Self {
-        self.cmd.stdin(input);
+    /// Specify a stdin input buffer.
+    pub fn stdin_buf<I: AsRef<[u8]>>(&mut self, input: I) -> &mut Self {
+        self.cmd.stdin_buf(input);
         self
     }
 
diff --git a/src/tools/run-make-support/src/lib.rs b/src/tools/run-make-support/src/lib.rs
index 989d00d4c2f..fefafb95b33 100644
--- a/src/tools/run-make-support/src/lib.rs
+++ b/src/tools/run-make-support/src/lib.rs
@@ -34,6 +34,7 @@ pub mod rfs {
 }
 
 // Re-exports of third-party library crates.
+// tidy-alphabetical-start
 pub use bstr;
 pub use gimli;
 pub use libc;
@@ -41,6 +42,7 @@ pub use object;
 pub use regex;
 pub use serde_json;
 pub use wasmparser;
+// tidy-alphabetical-end
 
 // Re-exports of external dependencies.
 pub use external_deps::{c_build, cc, clang, htmldocck, llvm, python, rustc, rustdoc};
diff --git a/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#0}-{closure#0}.coroutine_by_move.0.panic-abort.mir b/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#0}-{closure#0}.built.after.mir
index 1f5bb551b8e..7da33b8a094 100644
--- a/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#0}-{closure#0}.coroutine_by_move.0.panic-abort.mir
+++ b/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#0}-{closure#0}.built.after.mir
@@ -1,11 +1,11 @@
-// MIR for `main::{closure#0}::{closure#0}::{closure#0}` 0 coroutine_by_move
+// MIR for `main::{closure#0}::{closure#0}::{closure#0}` after built
 
-fn main::{closure#0}::{closure#0}::{closure#0}(_1: {async closure body@$DIR/async_closure_shims.rs:53:53: 56:10}, _2: ResumeTy) -> ()
+fn main::{closure#0}::{closure#0}::{closure#0}(_1: {async closure body@$DIR/async_closure_shims.rs:54:53: 57:10}, _2: ResumeTy) -> ()
 yields ()
  {
     debug _task_context => _2;
     debug a => (_1.0: i32);
-    debug b => (_1.1: i32);
+    debug b => (*(_1.1: &i32));
     let mut _0: ();
     let _3: i32;
     scope 1 {
@@ -28,7 +28,7 @@ yields ()
         _4 = &_3;
         FakeRead(ForLet(None), _4);
         StorageLive(_5);
-        _5 = &(_1.1: i32);
+        _5 = &(*(_1.1: &i32));
         FakeRead(ForLet(None), _5);
         _0 = const ();
         StorageDead(_5);
diff --git a/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#0}-{closure#0}.coroutine_by_move.0.panic-unwind.mir b/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#0}-{closure#1}.built.after.mir
index 1f5bb551b8e..a21e82ef5b6 100644
--- a/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#0}-{closure#0}.coroutine_by_move.0.panic-unwind.mir
+++ b/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#0}-{closure#1}.built.after.mir
@@ -1,6 +1,6 @@
-// MIR for `main::{closure#0}::{closure#0}::{closure#0}` 0 coroutine_by_move
+// MIR for `main::{closure#0}::{closure#0}::{closure#1}` after built
 
-fn main::{closure#0}::{closure#0}::{closure#0}(_1: {async closure body@$DIR/async_closure_shims.rs:53:53: 56:10}, _2: ResumeTy) -> ()
+fn main::{closure#0}::{closure#0}::{closure#1}(_1: {async closure body@$DIR/async_closure_shims.rs:54:53: 57:10}, _2: ResumeTy) -> ()
 yields ()
  {
     debug _task_context => _2;
diff --git a/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#0}.coroutine_closure_by_move.0.panic-abort.mir b/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#0}.coroutine_closure_by_move.0.mir
index a984845fd2c..c1566360995 100644
--- a/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#0}.coroutine_closure_by_move.0.panic-abort.mir
+++ b/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#0}.coroutine_closure_by_move.0.mir
@@ -1,10 +1,10 @@
 // MIR for `main::{closure#0}::{closure#0}` 0 coroutine_closure_by_move
 
-fn main::{closure#0}::{closure#0}(_1: {async closure@$DIR/async_closure_shims.rs:53:33: 53:52}, _2: i32) -> {async closure body@$DIR/async_closure_shims.rs:53:53: 56:10} {
-    let mut _0: {async closure body@$DIR/async_closure_shims.rs:53:53: 56:10};
+fn main::{closure#0}::{closure#0}(_1: {async closure@$DIR/async_closure_shims.rs:54:33: 54:52}, _2: i32) -> {async closure body@$DIR/async_closure_shims.rs:54:53: 57:10} {
+    let mut _0: {async closure body@$DIR/async_closure_shims.rs:54:53: 57:10};
 
     bb0: {
-        _0 = {coroutine@$DIR/async_closure_shims.rs:53:53: 56:10 (#0)} { a: move _2, b: move (_1.0: i32) };
+        _0 = {coroutine@$DIR/async_closure_shims.rs:54:53: 57:10 (#0)} { a: move _2, b: move (_1.0: i32) };
         return;
     }
 }
diff --git a/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#0}.coroutine_closure_by_move.0.panic-unwind.mir b/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#0}.coroutine_closure_by_move.0.panic-unwind.mir
deleted file mode 100644
index a984845fd2c..00000000000
--- a/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#0}.coroutine_closure_by_move.0.panic-unwind.mir
+++ /dev/null
@@ -1,10 +0,0 @@
-// MIR for `main::{closure#0}::{closure#0}` 0 coroutine_closure_by_move
-
-fn main::{closure#0}::{closure#0}(_1: {async closure@$DIR/async_closure_shims.rs:53:33: 53:52}, _2: i32) -> {async closure body@$DIR/async_closure_shims.rs:53:53: 56:10} {
-    let mut _0: {async closure body@$DIR/async_closure_shims.rs:53:53: 56:10};
-
-    bb0: {
-        _0 = {coroutine@$DIR/async_closure_shims.rs:53:53: 56:10 (#0)} { a: move _2, b: move (_1.0: i32) };
-        return;
-    }
-}
diff --git a/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}-{closure#0}.coroutine_by_move.0.panic-abort.mir b/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}-{closure#0}.built.after.mir
index 17fa9314806..a4a6a535a23 100644
--- a/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}-{closure#0}.coroutine_by_move.0.panic-abort.mir
+++ b/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}-{closure#0}.built.after.mir
@@ -1,6 +1,6 @@
-// MIR for `main::{closure#0}::{closure#1}::{closure#0}` 0 coroutine_by_move
+// MIR for `main::{closure#0}::{closure#1}::{closure#0}` after built
 
-fn main::{closure#0}::{closure#1}::{closure#0}(_1: {async closure body@$DIR/async_closure_shims.rs:62:48: 65:10}, _2: ResumeTy) -> ()
+fn main::{closure#0}::{closure#1}::{closure#0}(_1: {async closure body@$DIR/async_closure_shims.rs:63:48: 66:10}, _2: ResumeTy) -> ()
 yields ()
  {
     debug _task_context => _2;
diff --git a/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}-{closure#0}.coroutine_by_move.0.panic-unwind.mir b/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}-{closure#1}.built.after.mir
index 17fa9314806..69bba6f5194 100644
--- a/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}-{closure#0}.coroutine_by_move.0.panic-unwind.mir
+++ b/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}-{closure#1}.built.after.mir
@@ -1,6 +1,6 @@
-// MIR for `main::{closure#0}::{closure#1}::{closure#0}` 0 coroutine_by_move
+// MIR for `main::{closure#0}::{closure#1}::{closure#1}` after built
 
-fn main::{closure#0}::{closure#1}::{closure#0}(_1: {async closure body@$DIR/async_closure_shims.rs:62:48: 65:10}, _2: ResumeTy) -> ()
+fn main::{closure#0}::{closure#1}::{closure#1}(_1: {async closure body@$DIR/async_closure_shims.rs:63:48: 66:10}, _2: ResumeTy) -> ()
 yields ()
  {
     debug _task_context => _2;
diff --git a/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}.coroutine_closure_by_move.0.panic-abort.mir b/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}.coroutine_closure_by_move.0.mir
index aab9f7b03b9..134fe145bae 100644
--- a/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}.coroutine_closure_by_move.0.panic-abort.mir
+++ b/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}.coroutine_closure_by_move.0.mir
@@ -1,10 +1,10 @@
 // MIR for `main::{closure#0}::{closure#1}` 0 coroutine_closure_by_move
 
-fn main::{closure#0}::{closure#1}(_1: {async closure@$DIR/async_closure_shims.rs:62:33: 62:47}, _2: i32) -> {async closure body@$DIR/async_closure_shims.rs:62:48: 65:10} {
-    let mut _0: {async closure body@$DIR/async_closure_shims.rs:62:48: 65:10};
+fn main::{closure#0}::{closure#1}(_1: {async closure@$DIR/async_closure_shims.rs:63:33: 63:47}, _2: i32) -> {async closure body@$DIR/async_closure_shims.rs:63:48: 66:10} {
+    let mut _0: {async closure body@$DIR/async_closure_shims.rs:63:48: 66:10};
 
     bb0: {
-        _0 = {coroutine@$DIR/async_closure_shims.rs:62:48: 65:10 (#0)} { a: move _2, b: move (_1.0: &i32) };
+        _0 = {coroutine@$DIR/async_closure_shims.rs:63:48: 66:10 (#0)} { a: move _2, b: move (_1.0: &i32) };
         return;
     }
 }
diff --git a/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}.coroutine_closure_by_move.0.panic-unwind.mir b/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}.coroutine_closure_by_move.0.panic-unwind.mir
deleted file mode 100644
index aab9f7b03b9..00000000000
--- a/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}.coroutine_closure_by_move.0.panic-unwind.mir
+++ /dev/null
@@ -1,10 +0,0 @@
-// MIR for `main::{closure#0}::{closure#1}` 0 coroutine_closure_by_move
-
-fn main::{closure#0}::{closure#1}(_1: {async closure@$DIR/async_closure_shims.rs:62:33: 62:47}, _2: i32) -> {async closure body@$DIR/async_closure_shims.rs:62:48: 65:10} {
-    let mut _0: {async closure body@$DIR/async_closure_shims.rs:62:48: 65:10};
-
-    bb0: {
-        _0 = {coroutine@$DIR/async_closure_shims.rs:62:48: 65:10 (#0)} { a: move _2, b: move (_1.0: &i32) };
-        return;
-    }
-}
diff --git a/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}.coroutine_closure_by_ref.0.panic-abort.mir b/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}.coroutine_closure_by_ref.0.mir
index 3fdc81791de..f267d93bd60 100644
--- a/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}.coroutine_closure_by_ref.0.panic-abort.mir
+++ b/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}.coroutine_closure_by_ref.0.mir
@@ -1,10 +1,10 @@
 // MIR for `main::{closure#0}::{closure#1}` 0 coroutine_closure_by_ref
 
-fn main::{closure#0}::{closure#1}(_1: &{async closure@$DIR/async_closure_shims.rs:62:33: 62:47}, _2: i32) -> {async closure body@$DIR/async_closure_shims.rs:62:48: 65:10} {
-    let mut _0: {async closure body@$DIR/async_closure_shims.rs:62:48: 65:10};
+fn main::{closure#0}::{closure#1}(_1: &{async closure@$DIR/async_closure_shims.rs:63:33: 63:47}, _2: i32) -> {async closure body@$DIR/async_closure_shims.rs:63:48: 66:10} {
+    let mut _0: {async closure body@$DIR/async_closure_shims.rs:63:48: 66:10};
 
     bb0: {
-        _0 = {coroutine@$DIR/async_closure_shims.rs:62:48: 65:10 (#0)} { a: move _2, b: copy ((*_1).0: &i32) };
+        _0 = {coroutine@$DIR/async_closure_shims.rs:63:48: 66:10 (#0)} { a: move _2, b: copy ((*_1).0: &i32) };
         return;
     }
 }
diff --git a/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}.coroutine_closure_by_ref.0.panic-unwind.mir b/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}.coroutine_closure_by_ref.0.panic-unwind.mir
deleted file mode 100644
index 3fdc81791de..00000000000
--- a/tests/mir-opt/async_closure_shims.main-{closure#0}-{closure#1}.coroutine_closure_by_ref.0.panic-unwind.mir
+++ /dev/null
@@ -1,10 +0,0 @@
-// MIR for `main::{closure#0}::{closure#1}` 0 coroutine_closure_by_ref
-
-fn main::{closure#0}::{closure#1}(_1: &{async closure@$DIR/async_closure_shims.rs:62:33: 62:47}, _2: i32) -> {async closure body@$DIR/async_closure_shims.rs:62:48: 65:10} {
-    let mut _0: {async closure body@$DIR/async_closure_shims.rs:62:48: 65:10};
-
-    bb0: {
-        _0 = {coroutine@$DIR/async_closure_shims.rs:62:48: 65:10 (#0)} { a: move _2, b: copy ((*_1).0: &i32) };
-        return;
-    }
-}
diff --git a/tests/mir-opt/async_closure_shims.rs b/tests/mir-opt/async_closure_shims.rs
index 57c55ef055c..b2168ba0c46 100644
--- a/tests/mir-opt/async_closure_shims.rs
+++ b/tests/mir-opt/async_closure_shims.rs
@@ -1,6 +1,5 @@
 //@ edition:2021
 // skip-filecheck
-// EMIT_MIR_FOR_EACH_PANIC_STRATEGY
 
 #![feature(async_closure, noop_waker, async_fn_traits)]
 #![allow(unused)]
@@ -22,7 +21,7 @@ pub fn block_on<T>(fut: impl Future<Output = T>) -> T {
     }
 }
 
-async fn call(f: &mut impl AsyncFn(i32)) {
+async fn call(f: &impl AsyncFn(i32)) {
     f(0).await;
 }
 
@@ -43,10 +42,12 @@ async fn call_normal_mut<F: Future<Output = ()>>(f: &mut impl FnMut(i32) -> F) {
 }
 
 // EMIT_MIR async_closure_shims.main-{closure#0}-{closure#0}.coroutine_closure_by_move.0.mir
-// EMIT_MIR async_closure_shims.main-{closure#0}-{closure#0}-{closure#0}.coroutine_by_move.0.mir
+// EMIT_MIR async_closure_shims.main-{closure#0}-{closure#0}-{closure#0}.built.after.mir
+// EMIT_MIR async_closure_shims.main-{closure#0}-{closure#0}-{closure#1}.built.after.mir
 // EMIT_MIR async_closure_shims.main-{closure#0}-{closure#1}.coroutine_closure_by_ref.0.mir
 // EMIT_MIR async_closure_shims.main-{closure#0}-{closure#1}.coroutine_closure_by_move.0.mir
-// EMIT_MIR async_closure_shims.main-{closure#0}-{closure#1}-{closure#0}.coroutine_by_move.0.mir
+// EMIT_MIR async_closure_shims.main-{closure#0}-{closure#1}-{closure#0}.built.after.mir
+// EMIT_MIR async_closure_shims.main-{closure#0}-{closure#1}-{closure#1}.built.after.mir
 pub fn main() {
     block_on(async {
         let b = 2i32;
@@ -54,7 +55,7 @@ pub fn main() {
             let a = &a;
             let b = &b;
         };
-        call(&mut async_closure).await;
+        call(&async_closure).await;
         call_mut(&mut async_closure).await;
         call_once(async_closure).await;
 
diff --git a/tests/run-make/clear-error-blank-output/rmake.rs b/tests/run-make/clear-error-blank-output/rmake.rs
index e0f042cf805..22e030691f2 100644
--- a/tests/run-make/clear-error-blank-output/rmake.rs
+++ b/tests/run-make/clear-error-blank-output/rmake.rs
@@ -8,6 +8,6 @@
 use run_make_support::rustc;
 
 fn main() {
-    let output = rustc().output("").stdin(b"fn main() {}").run_fail();
+    let output = rustc().output("").stdin_buf(b"fn main() {}").run_fail();
     output.assert_stderr_not_contains("panic");
 }
diff --git a/tests/run-make/comment-section/rmake.rs b/tests/run-make/comment-section/rmake.rs
index 1557f50dbd0..ccfc38e870d 100644
--- a/tests/run-make/comment-section/rmake.rs
+++ b/tests/run-make/comment-section/rmake.rs
@@ -14,7 +14,7 @@ fn main() {
 
     rustc()
         .arg("-")
-        .stdin("fn main() {}")
+        .stdin_buf("fn main() {}")
         .emit("link,obj")
         .arg("-Csave-temps")
         .target(target)
diff --git a/tests/run-make/compile-stdin/rmake.rs b/tests/run-make/compile-stdin/rmake.rs
index f93080dfdc4..b8244335855 100644
--- a/tests/run-make/compile-stdin/rmake.rs
+++ b/tests/run-make/compile-stdin/rmake.rs
@@ -8,6 +8,6 @@
 use run_make_support::{run, rustc};
 
 fn main() {
-    rustc().arg("-").stdin("fn main() {}").run();
+    rustc().arg("-").stdin_buf("fn main() {}").run();
     run("rust_out");
 }
diff --git a/tests/run-make/libtest-junit/rmake.rs b/tests/run-make/libtest-junit/rmake.rs
index d631313ed92..5917660b6c7 100644
--- a/tests/run-make/libtest-junit/rmake.rs
+++ b/tests/run-make/libtest-junit/rmake.rs
@@ -21,7 +21,7 @@ fn run_tests(extra_args: &[&str], expected_file: &str) {
         .run_fail();
     let test_stdout = &cmd_out.stdout_utf8();
 
-    python_command().arg("validate_junit.py").stdin(test_stdout).run();
+    python_command().arg("validate_junit.py").stdin_buf(test_stdout).run();
 
     diff()
         .expected_file(expected_file)
diff --git a/tests/run-make/llvm-ident/rmake.rs b/tests/run-make/llvm-ident/rmake.rs
index 9699d0579f6..47e6fc4de15 100644
--- a/tests/run-make/llvm-ident/rmake.rs
+++ b/tests/run-make/llvm-ident/rmake.rs
@@ -17,7 +17,7 @@ fn main() {
         .codegen_units(16)
         .opt_level("2")
         .target(&env_var("TARGET"))
-        .stdin("fn main(){}")
+        .stdin_buf("fn main(){}")
         .run();
 
     // `llvm-dis` is used here since `--emit=llvm-ir` does not emit LLVM IR
diff --git a/tests/run-make/llvm-outputs/rmake.rs b/tests/run-make/llvm-outputs/rmake.rs
index b8ac21c98a0..632e9a09ba5 100644
--- a/tests/run-make/llvm-outputs/rmake.rs
+++ b/tests/run-make/llvm-outputs/rmake.rs
@@ -11,8 +11,8 @@ fn main() {
         let p = cwd();
         path_bc = p.join("nonexistant_dir_bc");
         path_ir = p.join("nonexistant_dir_ir");
-        rustc().input("-").stdin("fn main() {}").out_dir(&path_bc).emit("llvm-bc").run();
-        rustc().input("-").stdin("fn main() {}").out_dir(&path_ir).emit("llvm-ir").run();
+        rustc().input("-").stdin_buf("fn main() {}").out_dir(&path_bc).emit("llvm-bc").run();
+        rustc().input("-").stdin_buf("fn main() {}").out_dir(&path_ir).emit("llvm-ir").run();
         assert!(path_bc.exists());
         assert!(path_ir.exists());
     });
diff --git a/tests/run-make/no-builtins-attribute/rmake.rs b/tests/run-make/no-builtins-attribute/rmake.rs
index 1e15b0c03f1..7182c65a2c5 100644
--- a/tests/run-make/no-builtins-attribute/rmake.rs
+++ b/tests/run-make/no-builtins-attribute/rmake.rs
@@ -9,5 +9,5 @@ use run_make_support::{llvm_filecheck, rfs, rustc};
 fn main() {
     rustc().input("no_builtins.rs").emit("link").run();
     rustc().input("main.rs").emit("llvm-ir").run();
-    llvm_filecheck().patterns("filecheck.main.txt").stdin(rfs::read("main.ll")).run();
+    llvm_filecheck().patterns("filecheck.main.txt").stdin_buf(rfs::read("main.ll")).run();
 }
diff --git a/tests/run-make/pgo-branch-weights/rmake.rs b/tests/run-make/pgo-branch-weights/rmake.rs
index ef33d009dbb..105c2fafc5a 100644
--- a/tests/run-make/pgo-branch-weights/rmake.rs
+++ b/tests/run-make/pgo-branch-weights/rmake.rs
@@ -35,5 +35,8 @@ fn main() {
         .codegen_units(1)
         .emit("llvm-ir")
         .run();
-    llvm_filecheck().patterns("filecheck-patterns.txt").stdin(rfs::read("interesting.ll")).run();
+    llvm_filecheck()
+        .patterns("filecheck-patterns.txt")
+        .stdin_buf(rfs::read("interesting.ll"))
+        .run();
 }
diff --git a/tests/run-make/pgo-indirect-call-promotion/rmake.rs b/tests/run-make/pgo-indirect-call-promotion/rmake.rs
index d0ccfd8a4d7..28232eb2566 100644
--- a/tests/run-make/pgo-indirect-call-promotion/rmake.rs
+++ b/tests/run-make/pgo-indirect-call-promotion/rmake.rs
@@ -29,5 +29,8 @@ fn main() {
         .codegen_units(1)
         .emit("llvm-ir")
         .run();
-    llvm_filecheck().patterns("filecheck-patterns.txt").stdin(rfs::read("interesting.ll")).run();
+    llvm_filecheck()
+        .patterns("filecheck-patterns.txt")
+        .stdin_buf(rfs::read("interesting.ll"))
+        .run();
 }
diff --git a/tests/run-make/pgo-use/rmake.rs b/tests/run-make/pgo-use/rmake.rs
index cad49372266..276af9ea263 100644
--- a/tests/run-make/pgo-use/rmake.rs
+++ b/tests/run-make/pgo-use/rmake.rs
@@ -51,5 +51,5 @@ fn main() {
     let lines: Vec<_> = ir.lines().rev().collect();
     let mut reversed_ir = lines.join("\n");
     reversed_ir.push('\n');
-    llvm_filecheck().patterns("filecheck-patterns.txt").stdin(reversed_ir.as_bytes()).run();
+    llvm_filecheck().patterns("filecheck-patterns.txt").stdin_buf(reversed_ir.as_bytes()).run();
 }
diff --git a/tests/run-make/separate-link/rmake.rs b/tests/run-make/separate-link/rmake.rs
index e91b25489bc..0ec7334e75d 100644
--- a/tests/run-make/separate-link/rmake.rs
+++ b/tests/run-make/separate-link/rmake.rs
@@ -8,7 +8,7 @@
 use run_make_support::{run, rustc};
 
 fn main() {
-    rustc().stdin(b"fn main(){}").arg("-Zno-link").arg("-").run();
+    rustc().stdin_buf(b"fn main(){}").arg("-Zno-link").arg("-").run();
     rustc().arg("-Zlink-only").input("rust_out.rlink").run();
     run("rust_out");
 }
diff --git a/tests/run-make/static-pie/rmake.rs b/tests/run-make/static-pie/rmake.rs
index 74f86bb8163..1557c170f56 100644
--- a/tests/run-make/static-pie/rmake.rs
+++ b/tests/run-make/static-pie/rmake.rs
@@ -28,7 +28,7 @@ fn ok_compiler_version(compiler: &str) -> bool {
     }
 
     let compiler_output =
-        cmd(compiler).stdin(trigger).arg("-").arg("-E").arg("-x").arg("c").run().stdout_utf8();
+        cmd(compiler).stdin_buf(trigger).arg("-").arg("-E").arg("-x").arg("c").run().stdout_utf8();
     let re = Regex::new(r"(?m)^(\d+)").unwrap();
     let version: u32 =
         re.captures(&compiler_output).unwrap().get(1).unwrap().as_str().parse().unwrap();
diff --git a/tests/run-make/stdin-rustc/rmake.rs b/tests/run-make/stdin-rustc/rmake.rs
index 68e9cf2fbd8..2d634dd455e 100644
--- a/tests/run-make/stdin-rustc/rmake.rs
+++ b/tests/run-make/stdin-rustc/rmake.rs
@@ -14,7 +14,7 @@ const NOT_UTF8: &[u8] = &[0xff, 0xff, 0xff];
 
 fn main() {
     // echo $HELLO_WORLD | rustc -
-    rustc().arg("-").stdin(HELLO_WORLD).run();
+    rustc().arg("-").stdin_buf(HELLO_WORLD).run();
     assert!(
         PathBuf::from(if !is_windows() { "rust_out" } else { "rust_out.exe" })
             .try_exists()
@@ -22,7 +22,7 @@ fn main() {
     );
 
     // echo $NOT_UTF8 | rustc -
-    rustc().arg("-").stdin(NOT_UTF8).run_fail().assert_stderr_contains(
+    rustc().arg("-").stdin_buf(NOT_UTF8).run_fail().assert_stderr_contains(
         "error: couldn't read from stdin, as it did not contain valid UTF-8",
     );
 }
diff --git a/tests/run-make/stdin-rustdoc/rmake.rs b/tests/run-make/stdin-rustdoc/rmake.rs
index de47a24fbdd..30f97b8a2cd 100644
--- a/tests/run-make/stdin-rustdoc/rmake.rs
+++ b/tests/run-make/stdin-rustdoc/rmake.rs
@@ -15,11 +15,11 @@ fn main() {
     let out_dir = PathBuf::from("doc");
 
     // rustdoc -
-    rustdoc().arg("-").out_dir(&out_dir).stdin(INPUT).run();
+    rustdoc().arg("-").out_dir(&out_dir).stdin_buf(INPUT).run();
     assert!(out_dir.join("rust_out/struct.F.html").try_exists().unwrap());
 
     // rustdoc --test -
-    rustdoc().arg("--test").arg("-").stdin(INPUT).run();
+    rustdoc().arg("--test").arg("-").stdin_buf(INPUT).run();
 
     // rustdoc file.rs -
     rustdoc().arg("file.rs").arg("-").run_fail();
diff --git a/tests/run-make/sysroot-crates-are-unstable/rmake.rs b/tests/run-make/sysroot-crates-are-unstable/rmake.rs
index 2240d87237b..c81c7fafdab 100644
--- a/tests/run-make/sysroot-crates-are-unstable/rmake.rs
+++ b/tests/run-make/sysroot-crates-are-unstable/rmake.rs
@@ -34,7 +34,7 @@ fn check_crate_is_unstable(cr: &Crate) {
         .target(target())
         .extern_(name, path)
         .input("-")
-        .stdin(format!("extern crate {name};"))
+        .stdin_buf(format!("extern crate {name};"))
         .run_fail();
 
     // Make sure it failed for the intended reason, not some other reason.
diff --git a/tests/run-make/unknown-mod-stdin/rmake.rs b/tests/run-make/unknown-mod-stdin/rmake.rs
index 0fe5c78ed0f..6be3119c0fd 100644
--- a/tests/run-make/unknown-mod-stdin/rmake.rs
+++ b/tests/run-make/unknown-mod-stdin/rmake.rs
@@ -12,7 +12,7 @@
 use run_make_support::{diff, rustc};
 
 fn main() {
-    let out = rustc().crate_type("rlib").stdin(b"mod unknown;").arg("-").run_fail();
+    let out = rustc().crate_type("rlib").stdin_buf(b"mod unknown;").arg("-").run_fail();
     diff()
         .actual_text("actual-stdout", out.stdout_utf8())
         .expected_file("unknown-mod.stdout")
diff --git a/tests/run-make/x86_64-fortanix-unknown-sgx-lvi/rmake.rs b/tests/run-make/x86_64-fortanix-unknown-sgx-lvi/rmake.rs
index 130781a4293..e58762aeb6d 100644
--- a/tests/run-make/x86_64-fortanix-unknown-sgx-lvi/rmake.rs
+++ b/tests/run-make/x86_64-fortanix-unknown-sgx-lvi/rmake.rs
@@ -78,19 +78,23 @@ fn check(func_re: &str, mut checks: &str) {
     // This is because frame pointers are optional, and them being enabled requires
     // an additional `popq` in the pattern checking file.
     if func_re == "std::io::stdio::_print::[[:alnum:]]+" {
-        let output = llvm_filecheck().stdin(&dump).patterns(checks).run_unchecked();
+        let output = llvm_filecheck().stdin_buf(&dump).patterns(checks).run_unchecked();
         if !output.status().success() {
             checks = "print.without_frame_pointers.checks";
-            llvm_filecheck().stdin(&dump).patterns(checks).run();
+            llvm_filecheck().stdin_buf(&dump).patterns(checks).run();
         }
     } else {
-        llvm_filecheck().stdin(&dump).patterns(checks).run();
+        llvm_filecheck().stdin_buf(&dump).patterns(checks).run();
     }
     if !["rust_plus_one_global_asm", "cmake_plus_one_c_global_asm", "cmake_plus_one_cxx_global_asm"]
         .contains(&func_re)
     {
         // The assembler cannot avoid explicit `ret` instructions. Sequences
         // of `shlq $0x0, (%rsp); lfence; retq` are used instead.
-        llvm_filecheck().args(&["--implicit-check-not", "ret"]).stdin(dump).patterns(checks).run();
+        llvm_filecheck()
+            .args(&["--implicit-check-not", "ret"])
+            .stdin_buf(dump)
+            .patterns(checks)
+            .run();
     }
 }
diff --git a/tests/rustdoc-gui/code-example-buttons.goml b/tests/rustdoc-gui/code-example-buttons.goml
index 4f037ec79f5..c62683b45da 100644
--- a/tests/rustdoc-gui/code-example-buttons.goml
+++ b/tests/rustdoc-gui/code-example-buttons.goml
@@ -94,3 +94,24 @@ call-function: ("check-buttons",{
     "filter": "invert(0.5)",
     "filter_hover": "invert(0.35)",
 })
+
+define-function: (
+    "check-buttons-position",
+    [pre_selector],
+    block {
+        move-cursor-to: |pre_selector| + " .rust:not(.item-decl)"
+        store-position: (|pre_selector| + " .rust:not(.item-decl)", {"x": x, "y": y})
+        assert-position: (|pre_selector| + " .rust:not(.item-decl) + .button-holder", {
+            "y": |y| + 4,
+        })
+    }
+)
+
+call-function: ("check-buttons-position", {"pre_selector": ".example-wrap"})
+
+go-to: "file://" + |DOC_PATH| + "/scrape_examples/fn.test_many.html"
+// We should work as well for scraped examples.
+call-function: ("check-buttons-position", {"pre_selector": ".scraped-example .example-wrap"})
+// And also when the scraped example "title" goes above.
+set-window-size: (600, 600)
+call-function: ("check-buttons-position", {"pre_selector": ".scraped-example .example-wrap"})
diff --git a/tests/rustdoc-gui/docblock-code-block-line-number.goml b/tests/rustdoc-gui/docblock-code-block-line-number.goml
index 348ce0c992f..03f8f80b10d 100644
--- a/tests/rustdoc-gui/docblock-code-block-line-number.goml
+++ b/tests/rustdoc-gui/docblock-code-block-line-number.goml
@@ -5,6 +5,18 @@ go-to: "file://" + |DOC_PATH| + "/test_docs/fn.foo.html"
 // We check that without this setting, there is no line number displayed.
 assert-false: "pre.example-line-numbers"
 
+// All corners should be rounded.
+assert-css: (
+    ".example-wrap .rust",
+    {
+        "border-top-left-radius": "6px",
+        "border-bottom-left-radius": "6px",
+        "border-top-right-radius": "6px",
+        "border-bottom-right-radius": "6px",
+    },
+    ALL,
+)
+
 // We set the setting to show the line numbers on code examples.
 set-local-storage: {"rustdoc-line-numbers": "true"}
 reload:
@@ -29,9 +41,21 @@ define-function: (
                 "margin": "0px",
                 "padding": "14px 8px",
                 "text-align": "right",
+                // There should not be a radius on the right of the line numbers.
+                "border-top-left-radius": "6px",
+                "border-bottom-left-radius": "6px",
+                "border-top-right-radius": "0px",
+                "border-bottom-right-radius": "0px",
             },
             ALL,
         )
+        // There should not be a radius on the left of the line numbers.
+        assert-css: ("pre.example-line-numbers + .rust", {
+            "border-top-left-radius": "0px",
+            "border-bottom-left-radius": "0px",
+            "border-top-right-radius": "6px",
+            "border-bottom-right-radius": "6px",
+        })
     },
 )
 call-function: ("check-colors", {
@@ -64,7 +88,56 @@ wait-for: 100 // wait-for-false does not exist
 assert-false: "pre.example-line-numbers"
 assert-local-storage: {"rustdoc-line-numbers": "false" }
 
+// Check that the rounded corners are back.
+assert-css: (
+    ".example-wrap .rust",
+    {
+        "border-top-left-radius": "6px",
+        "border-bottom-left-radius": "6px",
+        "border-top-right-radius": "6px",
+        "border-bottom-right-radius": "6px",
+    },
+    ALL,
+)
+
 // Finally, turn it on again.
 click: "input#line-numbers"
 wait-for: "pre.example-line-numbers"
 assert-local-storage: {"rustdoc-line-numbers": "true" }
+
+// Same check with scraped examples line numbers.
+go-to: "file://" + |DOC_PATH| + "/scrape_examples/fn.test_many.html"
+
+assert-css: (
+    ".scraped-example .src-line-numbers > pre",
+    {
+        // There should not be a radius on the right of the line numbers.
+        "border-top-left-radius": "6px",
+        "border-bottom-left-radius": "6px",
+        "border-top-right-radius": "0px",
+        "border-bottom-right-radius": "0px",
+    },
+    ALL,
+)
+assert-css: (
+    ".scraped-example .src-line-numbers",
+    {
+        // There should not be a radius on the right of the line numbers.
+        "border-top-left-radius": "6px",
+        "border-bottom-left-radius": "6px",
+        "border-top-right-radius": "0px",
+        "border-bottom-right-radius": "0px",
+    },
+    ALL,
+)
+assert-css: (
+    ".scraped-example .rust",
+    {
+        // There should not be a radius on the left of the code.
+        "border-top-left-radius": "0px",
+        "border-bottom-left-radius": "0px",
+        "border-top-right-radius": "6px",
+        "border-bottom-right-radius": "6px",
+    },
+    ALL,
+)
diff --git a/tests/rustdoc-gui/scrape-examples-button-focus.goml b/tests/rustdoc-gui/scrape-examples-button-focus.goml
index af4293dfc00..83ed6a219b2 100644
--- a/tests/rustdoc-gui/scrape-examples-button-focus.goml
+++ b/tests/rustdoc-gui/scrape-examples-button-focus.goml
@@ -3,29 +3,53 @@
 go-to: "file://" + |DOC_PATH| + "/scrape_examples/fn.test.html"
 
 // The next/prev buttons vertically scroll the code viewport between examples
-store-property: (".scraped-example-list > .scraped-example pre", {"scrollTop": initialScrollTop})
+move-cursor-to: ".scraped-example-list > .scraped-example"
+store-property: (".scraped-example-list > .scraped-example .src-line-numbers", {
+    "scrollTop": initialScrollTop,
+})
+assert-property: (".scraped-example-list > .scraped-example .rust", {
+    "scrollTop": |initialScrollTop|,
+})
 focus: ".scraped-example-list > .scraped-example .next"
 press-key: "Enter"
-assert-property-false: (".scraped-example-list > .scraped-example pre", {
+assert-property-false: (".scraped-example-list > .scraped-example .src-line-numbers", {
+    "scrollTop": |initialScrollTop|
+}, NEAR)
+assert-property-false: (".scraped-example-list > .scraped-example .rust", {
     "scrollTop": |initialScrollTop|
 }, NEAR)
 focus: ".scraped-example-list > .scraped-example .prev"
 press-key: "Enter"
-assert-property: (".scraped-example-list > .scraped-example pre", {
+assert-property: (".scraped-example-list > .scraped-example .src-line-numbers", {
+    "scrollTop": |initialScrollTop|
+}, NEAR)
+assert-property: (".scraped-example-list > .scraped-example .rust", {
     "scrollTop": |initialScrollTop|
 }, NEAR)
 
 // The expand button increases the scrollHeight of the minimized code viewport
 store-property: (".scraped-example-list > .scraped-example pre", {"offsetHeight": smallOffsetHeight})
-assert-property-false: (".scraped-example-list > .scraped-example pre", {
+assert-property: (".scraped-example-list > .scraped-example .src-line-numbers", {
+    "scrollHeight": |smallOffsetHeight|
+}, NEAR)
+assert-property: (".scraped-example-list > .scraped-example .rust", {
     "scrollHeight": |smallOffsetHeight|
 }, NEAR)
 focus: ".scraped-example-list > .scraped-example .expand"
 press-key: "Enter"
-assert-property-false: (".scraped-example-list > .scraped-example pre", {
+assert-property-false: (".scraped-example-list > .scraped-example .src-line-numbers", {
+    "offsetHeight": |smallOffsetHeight|
+}, NEAR)
+assert-property-false: (".scraped-example-list > .scraped-example .rust", {
     "offsetHeight": |smallOffsetHeight|
 }, NEAR)
-store-property: (".scraped-example-list > .scraped-example pre", {"offsetHeight": fullOffsetHeight})
-assert-property: (".scraped-example-list > .scraped-example pre", {
+store-property: (".scraped-example-list > .scraped-example .src-line-numbers", {
+    "offsetHeight": fullOffsetHeight,
+})
+assert-property: (".scraped-example-list > .scraped-example .rust", {
+    "offsetHeight": |fullOffsetHeight|,
+    "scrollHeight": |fullOffsetHeight|,
+})
+assert-property: (".scraped-example-list > .scraped-example .src-line-numbers", {
     "scrollHeight": |fullOffsetHeight|
 }, NEAR)
diff --git a/tests/rustdoc-gui/scrape-examples-color.goml b/tests/rustdoc-gui/scrape-examples-color.goml
index 588ba08a60c..b0faca190a5 100644
--- a/tests/rustdoc-gui/scrape-examples-color.goml
+++ b/tests/rustdoc-gui/scrape-examples-color.goml
@@ -10,10 +10,10 @@ define-function: (
     block {
         call-function: ("switch-theme", {"theme": |theme|})
         wait-for: ".more-examples-toggle"
-        assert-css: (".scraped-example .example-wrap .rust span.highlight:not(.focus)", {
+        assert-css: (".scraped-example .rust span.highlight:not(.focus)", {
             "background-color": |highlight|,
         }, ALL)
-        assert-css: (".scraped-example .example-wrap .rust span.highlight.focus", {
+        assert-css: (".scraped-example .rust span.highlight.focus", {
             "background-color": |highlight_focus|,
         }, ALL)
 
@@ -67,11 +67,11 @@ define-function: (
     [theme, background_color_start, background_color_end],
     block {
         call-function: ("switch-theme", {"theme": |theme|})
-        assert-css: (".scraped-example:not(.expanded) .code-wrapper::before", {
+        assert-css: (".scraped-example:not(.expanded) .example-wrap::before", {
             "background-image": "linear-gradient(" + |background_color_start| + ", " +
                 |background_color_end| + ")",
         })
-        assert-css: (".scraped-example:not(.expanded) .code-wrapper::after", {
+        assert-css: (".scraped-example:not(.expanded) .example-wrap::after", {
             "background-image": "linear-gradient(to top, " + |background_color_start| + ", " +
                 |background_color_end| + ")",
         })
diff --git a/tests/rustdoc-gui/scrape-examples-layout.goml b/tests/rustdoc-gui/scrape-examples-layout.goml
index 4fc1c1ac065..6bea352bce4 100644
--- a/tests/rustdoc-gui/scrape-examples-layout.goml
+++ b/tests/rustdoc-gui/scrape-examples-layout.goml
@@ -1,48 +1,115 @@
 // Check that the line number column has the correct layout.
 go-to: "file://" + |DOC_PATH| + "/scrape_examples/fn.test_many.html"
 
+set-window-size: (1000, 1000)
+
 // Check that it's not zero.
 assert-property-false: (
-    ".more-scraped-examples .scraped-example .code-wrapper .src-line-numbers",
+    ".more-scraped-examples .scraped-example .src-line-numbers",
     {"clientWidth": "0"}
 )
 
 // Check that examples with very long lines have the same width as ones that don't.
 store-property: (
-    ".more-scraped-examples .scraped-example:nth-child(2) .code-wrapper .src-line-numbers",
+    ".more-scraped-examples .scraped-example:nth-child(2) .src-line-numbers",
     {"clientWidth": clientWidth},
 )
 
 assert-property: (
-    ".more-scraped-examples .scraped-example:nth-child(3) .code-wrapper .src-line-numbers",
+    ".more-scraped-examples .scraped-example:nth-child(3) .src-line-numbers",
     {"clientWidth": |clientWidth|}
 )
 
 assert-property: (
-    ".more-scraped-examples .scraped-example:nth-child(4) .code-wrapper .src-line-numbers",
+    ".more-scraped-examples .scraped-example:nth-child(4) .src-line-numbers",
     {"clientWidth": |clientWidth|}
 )
 
 assert-property: (
-    ".more-scraped-examples .scraped-example:nth-child(5) .code-wrapper .src-line-numbers",
+    ".more-scraped-examples .scraped-example:nth-child(5) .src-line-numbers",
     {"clientWidth": |clientWidth|}
 )
 
 assert-property: (
-    ".more-scraped-examples .scraped-example:nth-child(6) .code-wrapper .src-line-numbers",
+    ".more-scraped-examples .scraped-example:nth-child(6) .src-line-numbers",
     {"clientWidth": |clientWidth|}
 )
 
+// The "title" should be located at the right bottom corner of the code example.
+store-position: (".scraped-example .example-wrap", {"x": x, "y": y})
+store-size: (".scraped-example .example-wrap", {"width": width, "height": height})
+store-size: (".scraped-example .scraped-example-title", {
+    "width": title_width,
+    "height": title_height,
+})
+assert-position: (".scraped-example .scraped-example-title", {
+    "x": |x| + |width| - |title_width| - 5,
+    "y": |y| + |height| - |title_height| - 8,
+})
+
+// Check that the expand button works and also that line number aligns with code.
+move-cursor-to: ".scraped-example .rust"
+click: ".scraped-example .button-holder .expand"
+wait-for: ".scraped-example.expanded"
+// They should have the same y position.
+compare-elements-position: (
+    ".scraped-example.expanded .src-line-numbers pre span",
+    ".scraped-example.expanded .rust code",
+    ["y"],
+)
+// And they should have the same height.
+compare-elements-size: (
+    ".scraped-example.expanded .src-line-numbers",
+    ".scraped-example.expanded .rust",
+    ["height"],
+)
+// Collapse code again.
+click: ".scraped-example .button-holder .expand"
+
 // Check that for both mobile and desktop sizes, the buttons in scraped examples are displayed
 // correctly.
 
 store-value: (offset_y, 4)
 
 // First with desktop
-assert-position: (".scraped-example .code-wrapper", {"y": 226})
-assert-position: (".scraped-example .code-wrapper .prev", {"y": 226 + |offset_y|})
+assert-position: (".scraped-example", {"y": 226})
+assert-position: (".scraped-example .prev", {"y": 226 + |offset_y|})
+
+// Gradient background should be at the top of the code block.
+assert-css: (".scraped-example .example-wrap::before", {"top": "0px"})
+assert-css: (".scraped-example .example-wrap::after", {"bottom": "0px"})
 
 // Then with mobile
 set-window-size: (600, 600)
-assert-position: (".scraped-example .code-wrapper", {"y": 308})
-assert-position: (".scraped-example .code-wrapper .prev", {"y": 308 + |offset_y|})
+store-size: (".scraped-example .scraped-example-title", {"height": title_height})
+assert-position: (".scraped-example", {"y": 284})
+assert-position: (".scraped-example .prev", {"y": 284 + |offset_y| + |title_height|})
+
+define-function: (
+    "check_title_and_code_position",
+    [],
+    block {
+        // Title should be above the code.
+        store-position: (".scraped-example .example-wrap .src-line-numbers", {"x": x, "y": y})
+        store-size: (".scraped-example .scraped-example-title", { "height": title_height })
+
+        assert-position: (".scraped-example .scraped-example-title", {
+            "x": |x|, // same X position.
+            "y": |y| - |title_height|,
+        })
+
+        // Line numbers should be right beside the code.
+        compare-elements-position: (
+            ".scraped-example .example-wrap .src-line-numbers",
+            ".scraped-example .example-wrap .rust",
+            ["y"],
+        )
+    }
+)
+
+// Check that the title is now above the code.
+call-function: ("check_title_and_code_position", {})
+
+// Then with small mobile
+set-window-size: (300, 300)
+call-function: ("check_title_and_code_position", {})
diff --git a/tests/rustdoc-gui/src/theme_css/custom-theme.css b/tests/rustdoc-gui/src/theme_css/custom-theme.css
index a56c31ab9d2..366f09f22b2 100644
--- a/tests/rustdoc-gui/src/theme_css/custom-theme.css
+++ b/tests/rustdoc-gui/src/theme_css/custom-theme.css
@@ -23,6 +23,8 @@
 	--copy-path-button-color: #999;
 	--copy-path-img-filter: invert(50%);
 	--copy-path-img-hover-filter: invert(35%);
+        --code-example-button-color: #7f7f7f;
+	--code-example-button-hover-color: #a5a5a5;
 	--codeblock-error-hover-color: rgb(255, 0, 0);
 	--codeblock-error-color: rgba(255, 0, 0, .5);
 	--codeblock-ignore-hover-color: rgb(255, 142, 0);
diff --git a/tests/rustdoc/impl-associated-items-order.rs b/tests/rustdoc/impl-associated-items-order.rs
new file mode 100644
index 00000000000..759e0f0b400
--- /dev/null
+++ b/tests/rustdoc/impl-associated-items-order.rs
@@ -0,0 +1,42 @@
+// This test ensures that impl associated items always follow this order:
+//
+// 1. Consts
+// 2. Types
+// 3. Functions
+
+#![feature(inherent_associated_types)]
+#![allow(incomplete_features)]
+#![crate_name = "foo"]
+
+//@ has 'foo/struct.Bar.html'
+pub struct Bar;
+
+impl Bar {
+    //@ has - '//*[@id="implementations-list"]//*[@class="impl-items"]/section[3]/h4' \
+    // 'pub fn foo()'
+    pub fn foo() {}
+    //@ has - '//*[@id="implementations-list"]//*[@class="impl-items"]/section[1]/h4' \
+    // 'pub const X: u8 = 12u8'
+    pub const X: u8 = 12;
+    //@ has - '//*[@id="implementations-list"]//*[@class="impl-items"]/section[2]/h4' \
+    // 'pub type Y = u8'
+    pub type Y = u8;
+}
+
+pub trait Foo {
+    const W: u32;
+    fn yeay();
+    type Z;
+}
+
+impl Foo for Bar {
+    //@ has - '//*[@id="trait-implementations-list"]//*[@class="impl-items"]/section[2]/h4' \
+    // 'type Z = u8'
+    type Z = u8;
+    //@ has - '//*[@id="trait-implementations-list"]//*[@class="impl-items"]/section[1]/h4' \
+    // 'const W: u32 = 12u32'
+    const W: u32 = 12;
+    //@ has - '//*[@id="trait-implementations-list"]//*[@class="impl-items"]/section[3]/h4' \
+    // 'fn yeay()'
+    fn yeay() {}
+}
diff --git a/tests/rustdoc/impl-associated-items-sidebar.rs b/tests/rustdoc/impl-associated-items-sidebar.rs
new file mode 100644
index 00000000000..d393a577e50
--- /dev/null
+++ b/tests/rustdoc/impl-associated-items-sidebar.rs
@@ -0,0 +1,42 @@
+// This test ensures that impl/trait associated items are listed in the sidebar.
+
+// ignore-tidy-linelength
+
+#![feature(inherent_associated_types)]
+#![feature(associated_type_defaults)]
+#![allow(incomplete_features)]
+#![crate_name = "foo"]
+
+//@ has 'foo/struct.Bar.html'
+pub struct Bar;
+
+impl Bar {
+    //@ has - '//*[@class="sidebar-elems"]//h3[1]' 'Associated Constants'
+    //@ has - '//*[@class="sidebar-elems"]//ul[@class="block associatedconstant"]/li/a[@href="#associatedconstant.X"]' 'X'
+    pub const X: u8 = 12;
+    //@ has - '//*[@class="sidebar-elems"]//h3[2]' 'Associated Types'
+    //@ has - '//*[@class="sidebar-elems"]//ul[@class="block associatedtype"]/li/a[@href="#associatedtype.Y"]' 'Y'
+    pub type Y = u8;
+}
+
+//@ has 'foo/trait.Foo.html'
+pub trait Foo {
+    //@ has - '//*[@class="sidebar-elems"]//h3[5]' 'Required Methods'
+    //@ has - '//*[@class="sidebar-elems"]//ul[@class="block"][5]/li/a[@href="#tymethod.yeay"]' 'yeay'
+    fn yeay();
+    //@ has - '//*[@class="sidebar-elems"]//h3[6]' 'Provided Methods'
+    //@ has - '//*[@class="sidebar-elems"]//ul[@class="block"][6]/li/a[@href="#method.boo"]' 'boo'
+    fn boo() {}
+    //@ has - '//*[@class="sidebar-elems"]//h3[1]' 'Required Associated Constants'
+    //@ has - '//*[@class="sidebar-elems"]//ul[@class="block"][1]/li/a[@href="#associatedconstant.W"]' 'W'
+    const W: u32;
+    //@ has - '//*[@class="sidebar-elems"]//h3[2]' 'Provided Associated Constants'
+    //@ has - '//*[@class="sidebar-elems"]//ul[@class="block"][2]/li/a[@href="#associatedconstant.U"]' 'U'
+    const U: u32 = 0;
+    //@ has - '//*[@class="sidebar-elems"]//h3[3]' 'Required Associated Types'
+    //@ has - '//*[@class="sidebar-elems"]//ul[@class="block"][3]/li/a[@href="#associatedtype.Z"]' 'Z'
+    type Z;
+    //@ has - '//*[@class="sidebar-elems"]//h3[4]' 'Provided Associated Types'
+    //@ has - '//*[@class="sidebar-elems"]//ul[@class="block"][4]/li/a[@href="#associatedtype.T"]' 'T'
+    type T = u32;
+}
diff --git a/tests/ui/impl-trait/precise-capturing/overcaptures-2024-but-fine.rs b/tests/ui/impl-trait/precise-capturing/overcaptures-2024-but-fine.rs
new file mode 100644
index 00000000000..e30f785b0ae
--- /dev/null
+++ b/tests/ui/impl-trait/precise-capturing/overcaptures-2024-but-fine.rs
@@ -0,0 +1,15 @@
+//@ check-pass
+
+#![deny(impl_trait_overcaptures)]
+
+struct Ctxt<'tcx>(&'tcx ());
+
+// In `compute`, we don't care that we're "overcapturing" `'tcx`
+// in edition 2024, because it can be shortened at the call site
+// and we know it outlives `'_`.
+
+impl<'tcx> Ctxt<'tcx> {
+    fn compute(&self) -> impl Sized + '_ {}
+}
+
+fn main() {}