Auto merge of #93173 - matthiaskrgr:rollup-49bj7ta, r=matthiaskrgr

Rollup of 10 pull requests

Successful merges:

 - #91965 (Add more granular `--exclude` in `x.py`)
 - #92467 (Ensure that early-bound function lifetimes are always 'local')
 - #92586 (Set the allocation MIN_ALIGN for espidf to 4.)
 - #92835 (Improve error message for key="value" cfg arguments.)
 - #92843 (Improve string concatenation suggestion)
 - #92963 (Implement tuple array diagnostic)
 - #93046 (Use let_else in even more places)
 - #93109 (Improve `Arc` and `Rc` documentation)
 - #93134 (delete `Stdin::split` forwarder)
 - #93139 (rustdoc: fix overflow-wrap for table layouts)

Failed merges:

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

77 files changed, 643 insertions, 509 deletions

diff --git a/compiler/rustc_borrowck/src/universal_regions.rs b/compiler/rustc_borrowck/src/universal_regions.rs
index b986df403f9..16a903d5e59 100644
--- a/compiler/rustc_borrowck/src/universal_regions.rs
+++ b/compiler/rustc_borrowck/src/universal_regions.rs
@@ -180,8 +180,9 @@ pub enum RegionClassification {
     /// anywhere. There is only one, `'static`.
     Global,
 
-    /// An **external** region is only relevant for closures. In that
-    /// case, it refers to regions that are free in the closure type
+    /// An **external** region is only relevant for
+    /// closures, generators, and inline consts. In that
+    /// case, it refers to regions that are free in the type
     /// -- basically, something bound in the surrounding context.
     ///
     /// Consider this example:
@@ -198,8 +199,8 @@ pub enum RegionClassification {
     /// Here, the lifetimes `'a` and `'b` would be **external** to the
     /// closure.
     ///
-    /// If we are not analyzing a closure, there are no external
-    /// lifetimes.
+    /// If we are not analyzing a closure/generator/inline-const,
+    /// there are no external lifetimes.
     External,
 
     /// A **local** lifetime is one about which we know the full set
@@ -424,22 +425,30 @@ impl<'cx, 'tcx> UniversalRegionsBuilder<'cx, 'tcx> {
 
         let typeck_root_def_id = self.infcx.tcx.typeck_root_def_id(self.mir_def.did.to_def_id());
 
-        // If this is a closure or generator, then the late-bound regions from the enclosing
-        // function are actually external regions to us. For example, here, 'a is not local
-        // to the closure c (although it is local to the fn foo):
-        // fn foo<'a>() {
-        //     let c = || { let x: &'a u32 = ...; }
-        // }
-        if self.mir_def.did.to_def_id() != typeck_root_def_id {
+        // If this is is a 'root' body (not a closure/generator/inline const), then
+        // there are no extern regions, so the local regions start at the same
+        // position as the (empty) sub-list of extern regions
+        let first_local_index = if self.mir_def.did.to_def_id() == typeck_root_def_id {
+            first_extern_index
+        } else {
+            // If this is a closure, generator, or inline-const, then the late-bound regions from the enclosing
+            // function are actually external regions to us. For example, here, 'a is not local
+            // to the closure c (although it is local to the fn foo):
+            // fn foo<'a>() {
+            //     let c = || { let x: &'a u32 = ...; }
+            // }
             self.infcx
-                .replace_late_bound_regions_with_nll_infer_vars(self.mir_def.did, &mut indices)
-        }
-
-        let bound_inputs_and_output = self.compute_inputs_and_output(&indices, defining_ty);
+                .replace_late_bound_regions_with_nll_infer_vars(self.mir_def.did, &mut indices);
+            // Any regions created during the execution of `defining_ty` or during the above
+            // late-bound region replacement are all considered 'extern' regions
+            self.infcx.num_region_vars()
+        };
 
         // "Liberate" the late-bound regions. These correspond to
         // "local" free regions.
-        let first_local_index = self.infcx.num_region_vars();
+
+        let bound_inputs_and_output = self.compute_inputs_and_output(&indices, defining_ty);
+
         let inputs_and_output = self.infcx.replace_bound_regions_with_nll_infer_vars(
             FR,
             self.mir_def.did,
diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs b/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
index 3d5fd2f354e..c90e43a4060 100644
--- a/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
+++ b/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
@@ -1493,7 +1493,7 @@ fn generator_layout_and_saved_local_names<'tcx>(
 
     let state_arg = mir::Local::new(1);
     for var in &body.var_debug_info {
-        let place = if let mir::VarDebugInfoContents::Place(p) = var.value { p } else { continue };
+        let mir::VarDebugInfoContents::Place(place) = &var.value else { continue };
         if place.local != state_arg {
             continue;
         }
diff --git a/compiler/rustc_codegen_llvm/src/lib.rs b/compiler/rustc_codegen_llvm/src/lib.rs
index cea4595fbbf..f0612eaba80 100644
--- a/compiler/rustc_codegen_llvm/src/lib.rs
+++ b/compiler/rustc_codegen_llvm/src/lib.rs
@@ -7,6 +7,7 @@
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
 #![feature(bool_to_option)]
 #![feature(crate_visibility_modifier)]
+#![feature(let_else)]
 #![feature(extern_types)]
 #![feature(nll)]
 #![recursion_limit = "256"]
diff --git a/compiler/rustc_interface/src/interface.rs b/compiler/rustc_interface/src/interface.rs
index 3804e100307..26343561959 100644
--- a/compiler/rustc_interface/src/interface.rs
+++ b/compiler/rustc_interface/src/interface.rs
@@ -124,7 +124,16 @@ pub fn parse_cfgspecs(cfgspecs: Vec<String>) -> FxHashSet<(String, Option<String
                     Err(errs) => errs.into_iter().for_each(|mut err| err.cancel()),
                 }
 
-                error!(r#"expected `key` or `key="value"`"#);
+                // If the user tried to use a key="value" flag, but is missing the quotes, provide
+                // a hint about how to resolve this.
+                if s.contains("=") && !s.contains("=\"") && !s.ends_with("\"") {
+                    error!(concat!(
+                        r#"expected `key` or `key="value"`, ensure escaping is appropriate"#,
+                        r#" for your shell, try 'key="value"' or key=\"value\""#
+                    ));
+                } else {
+                    error!(r#"expected `key` or `key="value"`"#);
+                }
             })
             .collect::<CrateConfig>();
         cfg.into_iter().map(|(a, b)| (a.to_string(), b.map(|b| b.to_string()))).collect()
diff --git a/compiler/rustc_interface/src/lib.rs b/compiler/rustc_interface/src/lib.rs
index 2fc3759968f..b911b108a73 100644
--- a/compiler/rustc_interface/src/lib.rs
+++ b/compiler/rustc_interface/src/lib.rs
@@ -1,5 +1,6 @@
 #![feature(bool_to_option)]
 #![feature(box_patterns)]
+#![feature(let_else)]
 #![feature(internal_output_capture)]
 #![feature(thread_spawn_unchecked)]
 #![feature(nll)]
diff --git a/compiler/rustc_interface/src/util.rs b/compiler/rustc_interface/src/util.rs
index 3921187baa5..6d9183eda9d 100644
--- a/compiler/rustc_interface/src/util.rs
+++ b/compiler/rustc_interface/src/util.rs
@@ -717,57 +717,57 @@ impl<'a, 'b> ReplaceBodyWithLoop<'a, 'b> {
     }
 
     fn should_ignore_fn(ret_ty: &ast::FnRetTy) -> bool {
-        if let ast::FnRetTy::Ty(ref ty) = ret_ty {
-            fn involves_impl_trait(ty: &ast::Ty) -> bool {
-                match ty.kind {
-                    ast::TyKind::ImplTrait(..) => true,
-                    ast::TyKind::Slice(ref subty)
-                    | ast::TyKind::Array(ref subty, _)
-                    | ast::TyKind::Ptr(ast::MutTy { ty: ref subty, .. })
-                    | ast::TyKind::Rptr(_, ast::MutTy { ty: ref subty, .. })
-                    | ast::TyKind::Paren(ref subty) => involves_impl_trait(subty),
-                    ast::TyKind::Tup(ref tys) => any_involves_impl_trait(tys.iter()),
-                    ast::TyKind::Path(_, ref path) => {
-                        path.segments.iter().any(|seg| match seg.args.as_deref() {
-                            None => false,
-                            Some(&ast::GenericArgs::AngleBracketed(ref data)) => {
-                                data.args.iter().any(|arg| match arg {
-                                    ast::AngleBracketedArg::Arg(arg) => match arg {
-                                        ast::GenericArg::Type(ty) => involves_impl_trait(ty),
-                                        ast::GenericArg::Lifetime(_)
-                                        | ast::GenericArg::Const(_) => false,
-                                    },
-                                    ast::AngleBracketedArg::Constraint(c) => match c.kind {
-                                        ast::AssocConstraintKind::Bound { .. } => true,
-                                        ast::AssocConstraintKind::Equality { ref term } => {
-                                            match term {
-                                                Term::Ty(ty) => involves_impl_trait(ty),
-                                                // FIXME(...): This should check if the constant
-                                                // involves a trait impl, but for now ignore.
-                                                Term::Const(_) => false,
-                                            }
+        let ast::FnRetTy::Ty(ref ty) = ret_ty else {
+            return false;
+        };
+        fn involves_impl_trait(ty: &ast::Ty) -> bool {
+            match ty.kind {
+                ast::TyKind::ImplTrait(..) => true,
+                ast::TyKind::Slice(ref subty)
+                | ast::TyKind::Array(ref subty, _)
+                | ast::TyKind::Ptr(ast::MutTy { ty: ref subty, .. })
+                | ast::TyKind::Rptr(_, ast::MutTy { ty: ref subty, .. })
+                | ast::TyKind::Paren(ref subty) => involves_impl_trait(subty),
+                ast::TyKind::Tup(ref tys) => any_involves_impl_trait(tys.iter()),
+                ast::TyKind::Path(_, ref path) => {
+                    path.segments.iter().any(|seg| match seg.args.as_deref() {
+                        None => false,
+                        Some(&ast::GenericArgs::AngleBracketed(ref data)) => {
+                            data.args.iter().any(|arg| match arg {
+                                ast::AngleBracketedArg::Arg(arg) => match arg {
+                                    ast::GenericArg::Type(ty) => involves_impl_trait(ty),
+                                    ast::GenericArg::Lifetime(_) | ast::GenericArg::Const(_) => {
+                                        false
+                                    }
+                                },
+                                ast::AngleBracketedArg::Constraint(c) => match c.kind {
+                                    ast::AssocConstraintKind::Bound { .. } => true,
+                                    ast::AssocConstraintKind::Equality { ref term } => {
+                                        match term {
+                                            Term::Ty(ty) => involves_impl_trait(ty),
+                                            // FIXME(...): This should check if the constant
+                                            // involves a trait impl, but for now ignore.
+                                            Term::Const(_) => false,
                                         }
-                                    },
-                                })
-                            }
-                            Some(&ast::GenericArgs::Parenthesized(ref data)) => {
-                                any_involves_impl_trait(data.inputs.iter())
-                                    || ReplaceBodyWithLoop::should_ignore_fn(&data.output)
-                            }
-                        })
-                    }
-                    _ => false,
+                                    }
+                                },
+                            })
+                        }
+                        Some(&ast::GenericArgs::Parenthesized(ref data)) => {
+                            any_involves_impl_trait(data.inputs.iter())
+                                || ReplaceBodyWithLoop::should_ignore_fn(&data.output)
+                        }
+                    })
                 }
+                _ => false,
             }
+        }
 
-            fn any_involves_impl_trait<'a, I: Iterator<Item = &'a P<ast::Ty>>>(mut it: I) -> bool {
-                it.any(|subty| involves_impl_trait(subty))
-            }
-
-            involves_impl_trait(ty)
-        } else {
-            false
+        fn any_involves_impl_trait<'a, I: Iterator<Item = &'a P<ast::Ty>>>(mut it: I) -> bool {
+            it.any(|subty| involves_impl_trait(subty))
         }
+
+        involves_impl_trait(ty)
     }
 
     fn is_sig_const(sig: &ast::FnSig) -> bool {
diff --git a/compiler/rustc_mir_build/src/build/matches/mod.rs b/compiler/rustc_mir_build/src/build/matches/mod.rs
index 85950d82419..3294f2cf641 100644
--- a/compiler/rustc_mir_build/src/build/matches/mod.rs
+++ b/compiler/rustc_mir_build/src/build/matches/mod.rs
@@ -1347,23 +1347,22 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
 
         let mut otherwise = None;
         for match_pair in match_pairs {
-            if let PatKind::Or { ref pats } = *match_pair.pattern.kind {
-                let or_span = match_pair.pattern.span;
-                let place = match_pair.place;
-
-                first_candidate.visit_leaves(|leaf_candidate| {
-                    self.test_or_pattern(
-                        leaf_candidate,
-                        &mut otherwise,
-                        pats,
-                        or_span,
-                        place.clone(),
-                        fake_borrows,
-                    );
-                });
-            } else {
+            let PatKind::Or { ref pats } = &*match_pair.pattern.kind else {
                 bug!("Or-patterns should have been sorted to the end");
-            }
+            };
+            let or_span = match_pair.pattern.span;
+            let place = match_pair.place;
+
+            first_candidate.visit_leaves(|leaf_candidate| {
+                self.test_or_pattern(
+                    leaf_candidate,
+                    &mut otherwise,
+                    pats,
+                    or_span,
+                    place.clone(),
+                    fake_borrows,
+                );
+            });
         }
 
         let remainder_start = otherwise.unwrap_or_else(|| self.cfg.start_new_block());
diff --git a/compiler/rustc_mir_build/src/build/matches/test.rs b/compiler/rustc_mir_build/src/build/matches/test.rs
index 7ed5d1d67ab..f4bf28bfa5c 100644
--- a/compiler/rustc_mir_build/src/build/matches/test.rs
+++ b/compiler/rustc_mir_build/src/build/matches/test.rs
@@ -88,11 +88,8 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
         switch_ty: Ty<'tcx>,
         options: &mut FxIndexMap<&'tcx ty::Const<'tcx>, u128>,
     ) -> bool {
-        let match_pair = match candidate.match_pairs.iter().find(|mp| mp.place == *test_place) {
-            Some(match_pair) => match_pair,
-            _ => {
-                return false;
-            }
+        let Some(match_pair) = candidate.match_pairs.iter().find(|mp| mp.place == *test_place) else {
+            return false;
         };
 
         match *match_pair.pattern.kind {
diff --git a/compiler/rustc_resolve/src/late/diagnostics.rs b/compiler/rustc_resolve/src/late/diagnostics.rs
index 7b4fe6f0e07..7e1e5c78805 100644
--- a/compiler/rustc_resolve/src/late/diagnostics.rs
+++ b/compiler/rustc_resolve/src/late/diagnostics.rs
@@ -1171,9 +1171,7 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
         ident: Symbol,
         kind: &AssocItemKind,
     ) -> Option<Symbol> {
-        let module = if let Some((module, _)) = self.current_trait_ref {
-            module
-        } else {
+        let Some((module, _)) = &self.current_trait_ref else {
             return None;
         };
         if ident == kw::Underscore {
diff --git a/compiler/rustc_resolve/src/late/lifetimes.rs b/compiler/rustc_resolve/src/late/lifetimes.rs
index b077a5c9144..4c7bdb33fb8 100644
--- a/compiler/rustc_resolve/src/late/lifetimes.rs
+++ b/compiler/rustc_resolve/src/late/lifetimes.rs
@@ -1000,46 +1000,45 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
                 // `fn foo<'a>() -> MyAnonTy<'a> { ... }`
                 //          ^                 ^this gets resolved in the current scope
                 for lifetime in lifetimes {
-                    if let hir::GenericArg::Lifetime(lifetime) = lifetime {
-                        self.visit_lifetime(lifetime);
+                    let hir::GenericArg::Lifetime(lifetime) = lifetime else {
+                        continue
+                    };
+                    self.visit_lifetime(lifetime);
+
+                    // Check for predicates like `impl for<'a> Trait<impl OtherTrait<'a>>`
+                    // and ban them. Type variables instantiated inside binders aren't
+                    // well-supported at the moment, so this doesn't work.
+                    // In the future, this should be fixed and this error should be removed.
+                    let def = self.map.defs.get(&lifetime.hir_id).cloned();
+                    let Some(Region::LateBound(_, _, def_id, _)) = def else {
+                        continue
+                    };
+                    let Some(def_id) = def_id.as_local() else {
+                        continue
+                    };
+                    let hir_id = self.tcx.hir().local_def_id_to_hir_id(def_id);
+                    // Ensure that the parent of the def is an item, not HRTB
+                    let parent_id = self.tcx.hir().get_parent_node(hir_id);
+                    // FIXME(cjgillot) Can this check be replaced by
+                    // `let parent_is_item = parent_id.is_owner();`?
+                    let parent_is_item = if let Some(parent_def_id) = parent_id.as_owner() {
+                        matches!(self.tcx.hir().krate().owners.get(parent_def_id), Some(Some(_)),)
+                    } else {
+                        false
+                    };
 
-                        // Check for predicates like `impl for<'a> Trait<impl OtherTrait<'a>>`
-                        // and ban them. Type variables instantiated inside binders aren't
-                        // well-supported at the moment, so this doesn't work.
-                        // In the future, this should be fixed and this error should be removed.
-                        let def = self.map.defs.get(&lifetime.hir_id).cloned();
-                        if let Some(Region::LateBound(_, _, def_id, _)) = def {
-                            if let Some(def_id) = def_id.as_local() {
-                                let hir_id = self.tcx.hir().local_def_id_to_hir_id(def_id);
-                                // Ensure that the parent of the def is an item, not HRTB
-                                let parent_id = self.tcx.hir().get_parent_node(hir_id);
-                                // FIXME(cjgillot) Can this check be replaced by
-                                // `let parent_is_item = parent_id.is_owner();`?
-                                let parent_is_item =
-                                    if let Some(parent_def_id) = parent_id.as_owner() {
-                                        matches!(
-                                            self.tcx.hir().krate().owners.get(parent_def_id),
-                                            Some(Some(_)),
-                                        )
-                                    } else {
-                                        false
-                                    };
-
-                                if !parent_is_item {
-                                    if !self.trait_definition_only {
-                                        struct_span_err!(
-                                            self.tcx.sess,
-                                            lifetime.span,
-                                            E0657,
-                                            "`impl Trait` can only capture lifetimes \
-                                                bound at the fn or impl level"
-                                        )
-                                        .emit();
-                                    }
-                                    self.uninsert_lifetime_on_error(lifetime, def.unwrap());
-                                }
-                            }
+                    if !parent_is_item {
+                        if !self.trait_definition_only {
+                            struct_span_err!(
+                                self.tcx.sess,
+                                lifetime.span,
+                                E0657,
+                                "`impl Trait` can only capture lifetimes \
+                                    bound at the fn or impl level"
+                            )
+                            .emit();
                         }
+                        self.uninsert_lifetime_on_error(lifetime, def.unwrap());
                     }
                 }
 
diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs
index e94c600bb49..3fb42a2ec4a 100644
--- a/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs
+++ b/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs
@@ -840,39 +840,38 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> {
             };
 
             for refs_remaining in 0..refs_number {
-                if let ty::Ref(_, inner_ty, _) = suggested_ty.kind() {
-                    suggested_ty = inner_ty;
+                let ty::Ref(_, inner_ty, _) = suggested_ty.kind() else {
+                    break;
+                };
+                suggested_ty = inner_ty;
 
-                    let new_obligation = self.mk_trait_obligation_with_new_self_ty(
-                        obligation.param_env,
-                        trait_ref,
-                        suggested_ty,
-                    );
+                let new_obligation = self.mk_trait_obligation_with_new_self_ty(
+                    obligation.param_env,
+                    trait_ref,
+                    suggested_ty,
+                );
 
-                    if self.predicate_may_hold(&new_obligation) {
-                        let sp = self
-                            .tcx
-                            .sess
-                            .source_map()
-                            .span_take_while(span, |c| c.is_whitespace() || *c == '&');
+                if self.predicate_may_hold(&new_obligation) {
+                    let sp = self
+                        .tcx
+                        .sess
+                        .source_map()
+                        .span_take_while(span, |c| c.is_whitespace() || *c == '&');
 
-                        let remove_refs = refs_remaining + 1;
+                    let remove_refs = refs_remaining + 1;
 
-                        let msg = if remove_refs == 1 {
-                            "consider removing the leading `&`-reference".to_string()
-                        } else {
-                            format!("consider removing {} leading `&`-references", remove_refs)
-                        };
+                    let msg = if remove_refs == 1 {
+                        "consider removing the leading `&`-reference".to_string()
+                    } else {
+                        format!("consider removing {} leading `&`-references", remove_refs)
+                    };
 
-                        err.span_suggestion_short(
-                            sp,
-                            &msg,
-                            String::new(),
-                            Applicability::MachineApplicable,
-                        );
-                        break;
-                    }
-                } else {
+                    err.span_suggestion_short(
+                        sp,
+                        &msg,
+                        String::new(),
+                        Applicability::MachineApplicable,
+                    );
                     break;
                 }
             }
diff --git a/compiler/rustc_typeck/src/check/callee.rs b/compiler/rustc_typeck/src/check/callee.rs
index eea8f40635d..0fea0afb572 100644
--- a/compiler/rustc_typeck/src/check/callee.rs
+++ b/compiler/rustc_typeck/src/check/callee.rs
@@ -307,6 +307,36 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         }
     }
 
+    /// Give appropriate suggestion when encountering `[("a", 0) ("b", 1)]`, where the
+    /// likely intention is to create an array containing tuples.
+    fn maybe_suggest_bad_array_definition(
+        &self,
+        err: &mut DiagnosticBuilder<'a>,
+        call_expr: &'tcx hir::Expr<'tcx>,
+        callee_expr: &'tcx hir::Expr<'tcx>,
+    ) -> bool {
+        let hir_id = self.tcx.hir().get_parent_node(call_expr.hir_id);
+        let parent_node = self.tcx.hir().get(hir_id);
+        if let (
+            hir::Node::Expr(hir::Expr { kind: hir::ExprKind::Array(_), .. }),
+            hir::ExprKind::Tup(exp),
+            hir::ExprKind::Call(_, args),
+        ) = (parent_node, &callee_expr.kind, &call_expr.kind)
+        {
+            if args.len() == exp.len() {
+                let start = callee_expr.span.shrink_to_hi();
+                err.span_suggestion(
+                    start,
+                    "consider separating array elements with a comma",
+                    ",".to_string(),
+                    Applicability::MaybeIncorrect,
+                );
+                return true;
+            }
+        }
+        false
+    }
+
     fn confirm_builtin_call(
         &self,
         call_expr: &'tcx hir::Expr<'tcx>,
@@ -422,7 +452,9 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     _ => Res::Err,
                 };
 
-                err.span_label(call_expr.span, "call expression requires function");
+                if !self.maybe_suggest_bad_array_definition(&mut err, call_expr, callee_expr) {
+                    err.span_label(call_expr.span, "call expression requires function");
+                }
 
                 if let Some(span) = self.tcx.hir().res_span(def) {
                     let callee_ty = callee_ty.to_string();
diff --git a/compiler/rustc_typeck/src/check/op.rs b/compiler/rustc_typeck/src/check/op.rs
index c20c457de85..74516acbfcf 100644
--- a/compiler/rustc_typeck/src/check/op.rs
+++ b/compiler/rustc_typeck/src/check/op.rs
@@ -549,16 +549,9 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         is_assign: IsAssign,
         op: hir::BinOp,
     ) -> bool {
-        let source_map = self.tcx.sess.source_map();
-        let remove_borrow_msg = "String concatenation appends the string on the right to the \
-                                 string on the left and may require reallocation. This \
-                                 requires ownership of the string on the left";
-
-        let msg = "`to_owned()` can be used to create an owned `String` \
-                   from a string reference. String concatenation \
-                   appends the string on the right to the string \
-                   on the left and may require reallocation. This \
-                   requires ownership of the string on the left";
+        let str_concat_note = "string concatenation requires an owned `String` on the left";
+        let rm_borrow_msg = "remove the borrow to obtain an owned `String`";
+        let to_owned_msg = "create an owned `String` from a string reference";
 
         let string_type = self.tcx.get_diagnostic_item(sym::String);
         let is_std_string = |ty: Ty<'tcx>| match ty.ty_adt_def() {
@@ -574,31 +567,23 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     ) =>
             {
                 if let IsAssign::No = is_assign { // Do not supply this message if `&str += &str`
-                    err.span_label(
-                        op.span,
-                        "`+` cannot be used to concatenate two `&str` strings",
-                    );
-                    match source_map.span_to_snippet(lhs_expr.span) {
-                        Ok(lstring) => {
-                            err.span_suggestion(
-                                lhs_expr.span,
-                                if lstring.starts_with('&') {
-                                    remove_borrow_msg
-                                } else {
-                                    msg
-                                },
-                                if let Some(stripped) = lstring.strip_prefix('&') {
-                                    // let a = String::new();
-                                    // let _ = &a + "bar";
-                                    stripped.to_string()
-                                } else {
-                                    format!("{}.to_owned()", lstring)
-                                },
-                                Applicability::MachineApplicable,
-                            )
-                        }
-                        _ => err.help(msg),
-                    };
+                    err.span_label(op.span, "`+` cannot be used to concatenate two `&str` strings");
+                    err.note(str_concat_note);
+                    if let hir::ExprKind::AddrOf(_, _, lhs_inner_expr) = lhs_expr.kind {
+                        err.span_suggestion_verbose(
+                            lhs_expr.span.until(lhs_inner_expr.span),
+                            rm_borrow_msg,
+                            "".to_owned(),
+                            Applicability::MachineApplicable
+                        );
+                    } else {
+                        err.span_suggestion_verbose(
+                            lhs_expr.span.shrink_to_hi(),
+                            to_owned_msg,
+                            ".to_owned()".to_owned(),
+                            Applicability::MachineApplicable
+                        );
+                    }
                 }
                 true
             }
@@ -609,32 +594,30 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     op.span,
                     "`+` cannot be used to concatenate a `&str` with a `String`",
                 );
-                match (
-                    source_map.span_to_snippet(lhs_expr.span),
-                    source_map.span_to_snippet(rhs_expr.span),
-                    is_assign,
-                ) {
-                    (Ok(l), Ok(r), IsAssign::No) => {
-                        let to_string = if let Some(stripped) = l.strip_prefix('&') {
-                            // let a = String::new(); let b = String::new();
-                            // let _ = &a + b;
-                            stripped.to_string()
+                match is_assign {
+                    IsAssign::No => {
+                        let sugg_msg;
+                        let lhs_sugg = if let hir::ExprKind::AddrOf(_, _, lhs_inner_expr) = lhs_expr.kind {
+                            sugg_msg = "remove the borrow on the left and add one on the right";
+                            (lhs_expr.span.until(lhs_inner_expr.span), "".to_owned())
                         } else {
-                            format!("{}.to_owned()", l)
+                            sugg_msg = "create an owned `String` on the left and add a borrow on the right";
+                            (lhs_expr.span.shrink_to_hi(), ".to_owned()".to_owned())
                         };
-                        err.multipart_suggestion(
-                            msg,
-                            vec![
-                                (lhs_expr.span, to_string),
-                                (rhs_expr.span, format!("&{}", r)),
-                            ],
+                        let suggestions = vec![
+                            lhs_sugg,
+                            (rhs_expr.span.shrink_to_lo(), "&".to_owned()),
+                        ];
+                        err.multipart_suggestion_verbose(
+                            sugg_msg,
+                            suggestions,
                             Applicability::MachineApplicable,
                         );
                     }
-                    _ => {
-                        err.help(msg);
+                    IsAssign::Yes => {
+                        err.note(str_concat_note);
                     }
-                };
+                }
                 true
             }
             _ => false,
diff --git a/library/alloc/src/rc.rs b/library/alloc/src/rc.rs
index 33bee4324fd..bf5fcfdcbf5 100644
--- a/library/alloc/src/rc.rs
+++ b/library/alloc/src/rc.rs
@@ -451,12 +451,10 @@ impl<T> Rc<T> {
     ///
     /// let mut five = Rc::<u32>::new_uninit();
     ///
-    /// let five = unsafe {
-    ///     // Deferred initialization:
-    ///     Rc::get_mut_unchecked(&mut five).as_mut_ptr().write(5);
+    /// // Deferred initialization:
+    /// Rc::get_mut(&mut five).unwrap().write(5);
     ///
-    ///     five.assume_init()
-    /// };
+    /// let five = unsafe { five.assume_init() };
     ///
     /// assert_eq!(*five, 5)
     /// ```
@@ -543,12 +541,10 @@ impl<T> Rc<T> {
     ///
     /// let mut five = Rc::<u32>::try_new_uninit()?;
     ///
-    /// let five = unsafe {
-    ///     // Deferred initialization:
-    ///     Rc::get_mut_unchecked(&mut five).as_mut_ptr().write(5);
+    /// // Deferred initialization:
+    /// Rc::get_mut(&mut five).unwrap().write(5);
     ///
-    ///     five.assume_init()
-    /// };
+    /// let five = unsafe { five.assume_init() };
     ///
     /// assert_eq!(*five, 5);
     /// # Ok::<(), std::alloc::AllocError>(())
@@ -660,14 +656,13 @@ impl<T> Rc<[T]> {
     ///
     /// let mut values = Rc::<[u32]>::new_uninit_slice(3);
     ///
-    /// let values = unsafe {
-    ///     // Deferred initialization:
-    ///     Rc::get_mut_unchecked(&mut values)[0].as_mut_ptr().write(1);
-    ///     Rc::get_mut_unchecked(&mut values)[1].as_mut_ptr().write(2);
-    ///     Rc::get_mut_unchecked(&mut values)[2].as_mut_ptr().write(3);
+    /// // Deferred initialization:
+    /// let data = Rc::get_mut(&mut values).unwrap();
+    /// data[0].write(1);
+    /// data[1].write(2);
+    /// data[2].write(3);
     ///
-    ///     values.assume_init()
-    /// };
+    /// let values = unsafe { values.assume_init() };
     ///
     /// assert_eq!(*values, [1, 2, 3])
     /// ```
@@ -738,12 +733,10 @@ impl<T> Rc<mem::MaybeUninit<T>> {
     ///
     /// let mut five = Rc::<u32>::new_uninit();
     ///
-    /// let five = unsafe {
-    ///     // Deferred initialization:
-    ///     Rc::get_mut_unchecked(&mut five).as_mut_ptr().write(5);
+    /// // Deferred initialization:
+    /// Rc::get_mut(&mut five).unwrap().write(5);
     ///
-    ///     five.assume_init()
-    /// };
+    /// let five = unsafe { five.assume_init() };
     ///
     /// assert_eq!(*five, 5)
     /// ```
@@ -777,14 +770,13 @@ impl<T> Rc<[mem::MaybeUninit<T>]> {
     ///
     /// let mut values = Rc::<[u32]>::new_uninit_slice(3);
     ///
-    /// let values = unsafe {
-    ///     // Deferred initialization:
-    ///     Rc::get_mut_unchecked(&mut values)[0].as_mut_ptr().write(1);
-    ///     Rc::get_mut_unchecked(&mut values)[1].as_mut_ptr().write(2);
-    ///     Rc::get_mut_unchecked(&mut values)[2].as_mut_ptr().write(3);
+    /// // Deferred initialization:
+    /// let data = Rc::get_mut(&mut values).unwrap();
+    /// data[0].write(1);
+    /// data[1].write(2);
+    /// data[2].write(3);
     ///
-    ///     values.assume_init()
-    /// };
+    /// let values = unsafe { values.assume_init() };
     ///
     /// assert_eq!(*values, [1, 2, 3])
     /// ```
diff --git a/library/alloc/src/sync.rs b/library/alloc/src/sync.rs
index 7c065f37d1f..ab8a44b2147 100644
--- a/library/alloc/src/sync.rs
+++ b/library/alloc/src/sync.rs
@@ -437,12 +437,10 @@ impl<T> Arc<T> {
     ///
     /// let mut five = Arc::<u32>::new_uninit();
     ///
-    /// let five = unsafe {
-    ///     // Deferred initialization:
-    ///     Arc::get_mut_unchecked(&mut five).as_mut_ptr().write(5);
+    /// // Deferred initialization:
+    /// Arc::get_mut(&mut five).unwrap().write(5);
     ///
-    ///     five.assume_init()
-    /// };
+    /// let five = unsafe { five.assume_init() };
     ///
     /// assert_eq!(*five, 5)
     /// ```
@@ -545,12 +543,10 @@ impl<T> Arc<T> {
     ///
     /// let mut five = Arc::<u32>::try_new_uninit()?;
     ///
-    /// let five = unsafe {
-    ///     // Deferred initialization:
-    ///     Arc::get_mut_unchecked(&mut five).as_mut_ptr().write(5);
+    /// // Deferred initialization:
+    /// Arc::get_mut(&mut five).unwrap().write(5);
     ///
-    ///     five.assume_init()
-    /// };
+    /// let five = unsafe { five.assume_init() };
     ///
     /// assert_eq!(*five, 5);
     /// # Ok::<(), std::alloc::AllocError>(())
@@ -652,14 +648,13 @@ impl<T> Arc<[T]> {
     ///
     /// let mut values = Arc::<[u32]>::new_uninit_slice(3);
     ///
-    /// let values = unsafe {
-    ///     // Deferred initialization:
-    ///     Arc::get_mut_unchecked(&mut values)[0].as_mut_ptr().write(1);
-    ///     Arc::get_mut_unchecked(&mut values)[1].as_mut_ptr().write(2);
-    ///     Arc::get_mut_unchecked(&mut values)[2].as_mut_ptr().write(3);
+    /// // Deferred initialization:
+    /// let data = Arc::get_mut(&mut values).unwrap();
+    /// data[0].write(1);
+    /// data[1].write(2);
+    /// data[2].write(3);
     ///
-    ///     values.assume_init()
-    /// };
+    /// let values = unsafe { values.assume_init() };
     ///
     /// assert_eq!(*values, [1, 2, 3])
     /// ```
@@ -730,12 +725,10 @@ impl<T> Arc<mem::MaybeUninit<T>> {
     ///
     /// let mut five = Arc::<u32>::new_uninit();
     ///
-    /// let five = unsafe {
-    ///     // Deferred initialization:
-    ///     Arc::get_mut_unchecked(&mut five).as_mut_ptr().write(5);
+    /// // Deferred initialization:
+    /// Arc::get_mut(&mut five).unwrap().write(5);
     ///
-    ///     five.assume_init()
-    /// };
+    /// let five = unsafe { five.assume_init() };
     ///
     /// assert_eq!(*five, 5)
     /// ```
@@ -770,14 +763,13 @@ impl<T> Arc<[mem::MaybeUninit<T>]> {
     ///
     /// let mut values = Arc::<[u32]>::new_uninit_slice(3);
     ///
-    /// let values = unsafe {
-    ///     // Deferred initialization:
-    ///     Arc::get_mut_unchecked(&mut values)[0].as_mut_ptr().write(1);
-    ///     Arc::get_mut_unchecked(&mut values)[1].as_mut_ptr().write(2);
-    ///     Arc::get_mut_unchecked(&mut values)[2].as_mut_ptr().write(3);
+    /// // Deferred initialization:
+    /// let data = Arc::get_mut(&mut values).unwrap();
+    /// data[0].write(1);
+    /// data[1].write(2);
+    /// data[2].write(3);
     ///
-    ///     values.assume_init()
-    /// };
+    /// let values = unsafe { values.assume_init() };
     ///
     /// assert_eq!(*values, [1, 2, 3])
     /// ```
diff --git a/library/std/src/ffi/c_str.rs b/library/std/src/ffi/c_str.rs
index d859bff1a45..66fee2fe548 100644
--- a/library/std/src/ffi/c_str.rs
+++ b/library/std/src/ffi/c_str.rs
@@ -973,7 +973,8 @@ impl<'a> From<&'a CString> for Cow<'a, CStr> {
 
 #[stable(feature = "shared_from_slice2", since = "1.24.0")]
 impl From<CString> for Arc<CStr> {
-    /// Converts a [`CString`] into an <code>[Arc]<[CStr]></code> without copying or allocating.
+    /// Converts a [`CString`] into an <code>[Arc]<[CStr]></code> by moving the [`CString`]
+    /// data into a new [`Arc`] buffer.
     #[inline]
     fn from(s: CString) -> Arc<CStr> {
         let arc: Arc<[u8]> = Arc::from(s.into_inner());
@@ -992,7 +993,8 @@ impl From<&CStr> for Arc<CStr> {
 
 #[stable(feature = "shared_from_slice2", since = "1.24.0")]
 impl From<CString> for Rc<CStr> {
-    /// Converts a [`CString`] into an <code>[Rc]<[CStr]></code> without copying or allocating.
+    /// Converts a [`CString`] into an <code>[Rc]<[CStr]></code> by moving the [`CString`]
+    /// data into a new [`Arc`] buffer.
     #[inline]
     fn from(s: CString) -> Rc<CStr> {
         let rc: Rc<[u8]> = Rc::from(s.into_inner());
diff --git a/library/std/src/ffi/os_str.rs b/library/std/src/ffi/os_str.rs
index 982ad189878..81f72e34d93 100644
--- a/library/std/src/ffi/os_str.rs
+++ b/library/std/src/ffi/os_str.rs
@@ -989,7 +989,8 @@ impl Clone for Box<OsStr> {
 
 #[stable(feature = "shared_from_slice2", since = "1.24.0")]
 impl From<OsString> for Arc<OsStr> {
-    /// Converts an [`OsString`] into an <code>[Arc]<[OsStr]></code> without copying or allocating.
+    /// Converts an [`OsString`] into an <code>[Arc]<[OsStr]></code> by moving the [`OsString`]
+    /// data into a new [`Arc`] buffer.
     #[inline]
     fn from(s: OsString) -> Arc<OsStr> {
         let arc = s.inner.into_arc();
@@ -1008,7 +1009,8 @@ impl From<&OsStr> for Arc<OsStr> {
 
 #[stable(feature = "shared_from_slice2", since = "1.24.0")]
 impl From<OsString> for Rc<OsStr> {
-    /// Converts an [`OsString`] into an <code>[Rc]<[OsStr]></code> without copying or allocating.
+    /// Converts an [`OsString`] into an <code>[Rc]<[OsStr]></code> by moving the [`OsString`]
+    /// data into a new [`Rc`] buffer.
     #[inline]
     fn from(s: OsString) -> Rc<OsStr> {
         let rc = s.inner.into_rc();
diff --git a/library/std/src/io/stdio.rs b/library/std/src/io/stdio.rs
index c072f0cafe4..3d6de20d860 100644
--- a/library/std/src/io/stdio.rs
+++ b/library/std/src/io/stdio.rs
@@ -7,7 +7,7 @@ use crate::io::prelude::*;
 
 use crate::cell::{Cell, RefCell};
 use crate::fmt;
-use crate::io::{self, BufReader, IoSlice, IoSliceMut, LineWriter, Lines, Split};
+use crate::io::{self, BufReader, IoSlice, IoSliceMut, LineWriter, Lines};
 use crate::lazy::SyncOnceCell;
 use crate::pin::Pin;
 use crate::sync::atomic::{AtomicBool, Ordering};
@@ -465,29 +465,6 @@ impl Stdin {
     pub fn lines(self) -> Lines<StdinLock<'static>> {
         self.into_locked().lines()
     }
-
-    /// Consumes this handle and returns an iterator over input bytes,
-    /// split at the specified byte value.
-    ///
-    /// For detailed semantics of this method, see the documentation on
-    /// [`BufRead::split`].
-    ///
-    /// # Examples
-    ///
-    /// ```no_run
-    /// #![feature(stdin_forwarders)]
-    /// use std::io;
-    ///
-    /// let splits = io::stdin().split(b'-');
-    /// for split in splits {
-    ///     println!("got a chunk: {}", String::from_utf8_lossy(&split.unwrap()));
-    /// }
-    /// ```
-    #[must_use = "`self` will be dropped if the result is not used"]
-    #[unstable(feature = "stdin_forwarders", issue = "87096")]
-    pub fn split(self, byte: u8) -> Split<StdinLock<'static>> {
-        self.into_locked().split(byte)
-    }
 }
 
 #[stable(feature = "std_debug", since = "1.16.0")]
diff --git a/library/std/src/path.rs b/library/std/src/path.rs
index f509403fe2e..558333518f1 100644
--- a/library/std/src/path.rs
+++ b/library/std/src/path.rs
@@ -1766,7 +1766,8 @@ impl<'a> From<Cow<'a, Path>> for PathBuf {
 
 #[stable(feature = "shared_from_slice2", since = "1.24.0")]
 impl From<PathBuf> for Arc<Path> {
-    /// Converts a [`PathBuf`] into an [`Arc`] by moving the [`PathBuf`] data into a new [`Arc`] buffer.
+    /// Converts a [`PathBuf`] into an <code>[Arc]<[Path]></code> by moving the [`PathBuf`] data
+    /// into a new [`Arc`] buffer.
     #[inline]
     fn from(s: PathBuf) -> Arc<Path> {
         let arc: Arc<OsStr> = Arc::from(s.into_os_string());
@@ -1786,7 +1787,8 @@ impl From<&Path> for Arc<Path> {
 
 #[stable(feature = "shared_from_slice2", since = "1.24.0")]
 impl From<PathBuf> for Rc<Path> {
-    /// Converts a [`PathBuf`] into an [`Rc`] by moving the [`PathBuf`] data into a new `Rc` buffer.
+    /// Converts a [`PathBuf`] into an <code>[Rc]<[Path]></code> by moving the [`PathBuf`] data into
+    /// a new [`Rc`] buffer.
     #[inline]
     fn from(s: PathBuf) -> Rc<Path> {
         let rc: Rc<OsStr> = Rc::from(s.into_os_string());
@@ -1796,7 +1798,7 @@ impl From<PathBuf> for Rc<Path> {
 
 #[stable(feature = "shared_from_slice2", since = "1.24.0")]
 impl From<&Path> for Rc<Path> {
-    /// Converts a [`Path`] into an [`Rc`] by copying the [`Path`] data into a new `Rc` buffer.
+    /// Converts a [`Path`] into an [`Rc`] by copying the [`Path`] data into a new [`Rc`] buffer.
     #[inline]
     fn from(s: &Path) -> Rc<Path> {
         let rc: Rc<OsStr> = Rc::from(s.as_os_str());
diff --git a/library/std/src/sys/common/alloc.rs b/library/std/src/sys/common/alloc.rs
index 9665d1fa892..e06eaf6db1a 100644
--- a/library/std/src/sys/common/alloc.rs
+++ b/library/std/src/sys/common/alloc.rs
@@ -14,8 +14,8 @@ use crate::ptr;
     target_arch = "asmjs",
     target_arch = "wasm32",
     target_arch = "hexagon",
-    target_arch = "riscv32",
-    target_arch = "xtensa"
+    all(target_arch = "riscv32", not(target_os = "espidf")),
+    all(target_arch = "xtensa", not(target_os = "espidf")),
 )))]
 pub const MIN_ALIGN: usize = 8;
 #[cfg(all(any(
@@ -28,6 +28,12 @@ pub const MIN_ALIGN: usize = 8;
     target_arch = "wasm64",
 )))]
 pub const MIN_ALIGN: usize = 16;
+// The allocator on the esp-idf platform guarentees 4 byte alignment.
+#[cfg(all(any(
+    all(target_arch = "riscv32", target_os = "espidf"),
+    all(target_arch = "xtensa", target_os = "espidf"),
+)))]
+pub const MIN_ALIGN: usize = 4;
 
 pub unsafe fn realloc_fallback(
     alloc: &System,
diff --git a/src/bootstrap/builder.rs b/src/bootstrap/builder.rs
index 6ccf8b1d522..5cab3e8be10 100644
--- a/src/bootstrap/builder.rs
+++ b/src/bootstrap/builder.rs
@@ -7,7 +7,7 @@ use std::fmt::Debug;
 use std::fs;
 use std::hash::Hash;
 use std::ops::Deref;
-use std::path::{Path, PathBuf};
+use std::path::{Component, Path, PathBuf};
 use std::process::Command;
 use std::time::{Duration, Instant};
 
@@ -105,6 +105,44 @@ struct StepDescription {
     should_run: fn(ShouldRun<'_>) -> ShouldRun<'_>,
     make_run: fn(RunConfig<'_>),
     name: &'static str,
+    kind: Kind,
+}
+
+#[derive(Clone, PartialOrd, Ord, PartialEq, Eq)]
+pub struct TaskPath {
+    pub path: PathBuf,
+    pub kind: Option<Kind>,
+}
+
+impl TaskPath {
+    pub fn parse(path: impl Into<PathBuf>) -> TaskPath {
+        let mut kind = None;
+        let mut path = path.into();
+
+        let mut components = path.components();
+        if let Some(Component::Normal(os_str)) = components.next() {
+            if let Some(str) = os_str.to_str() {
+                if let Some((found_kind, found_prefix)) = str.split_once("::") {
+                    if found_kind.is_empty() {
+                        panic!("empty kind in task path {}", path.display());
+                    }
+                    kind = Some(Kind::parse(found_kind));
+                    path = Path::new(found_prefix).join(components.as_path());
+                }
+            }
+        }
+
+        TaskPath { path, kind }
+    }
+}
+
+impl Debug for TaskPath {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        if let Some(kind) = &self.kind {
+            write!(f, "{}::", kind.as_str())?;
+        }
+        write!(f, "{}", self.path.display())
+    }
 }
 
 /// Collection of paths used to match a task rule.
@@ -115,14 +153,14 @@ pub enum PathSet {
     /// These are generally matched as a path suffix. For example, a
     /// command-line value of `libstd` will match if `src/libstd` is in the
     /// set.
-    Set(BTreeSet<PathBuf>),
+    Set(BTreeSet<TaskPath>),
     /// A "suite" of paths.
     ///
     /// These can match as a path suffix (like `Set`), or as a prefix. For
     /// example, a command-line value of `src/test/ui/abi/variadic-ffi.rs`
     /// will match `src/test/ui`. A command-line value of `ui` would also
     /// match `src/test/ui`.
-    Suite(PathBuf),
+    Suite(TaskPath),
 }
 
 impl PathSet {
@@ -130,35 +168,46 @@ impl PathSet {
         PathSet::Set(BTreeSet::new())
     }
 
-    fn one<P: Into<PathBuf>>(path: P) -> PathSet {
+    fn one<P: Into<PathBuf>>(path: P, kind: Kind) -> PathSet {
         let mut set = BTreeSet::new();
-        set.insert(path.into());
+        set.insert(TaskPath { path: path.into(), kind: Some(kind.into()) });
         PathSet::Set(set)
     }
 
-    fn has(&self, needle: &Path) -> bool {
+    fn has(&self, needle: &Path, module: Option<Kind>) -> bool {
+        let check = |p: &TaskPath| {
+            if let (Some(p_kind), Some(kind)) = (&p.kind, module) {
+                p.path.ends_with(needle) && *p_kind == kind
+            } else {
+                p.path.ends_with(needle)
+            }
+        };
+
         match self {
-            PathSet::Set(set) => set.iter().any(|p| p.ends_with(needle)),
-            PathSet::Suite(suite) => suite.ends_with(needle),
+            PathSet::Set(set) => set.iter().any(check),
+            PathSet::Suite(suite) => check(suite),
         }
     }
 
     fn path(&self, builder: &Builder<'_>) -> PathBuf {
         match self {
-            PathSet::Set(set) => set.iter().next().unwrap_or(&builder.build.src).to_path_buf(),
-            PathSet::Suite(path) => PathBuf::from(path),
+            PathSet::Set(set) => {
+                set.iter().next().map(|p| &p.path).unwrap_or(&builder.build.src).clone()
+            }
+            PathSet::Suite(path) => path.path.clone(),
         }
     }
 }
 
 impl StepDescription {
-    fn from<S: Step>() -> StepDescription {
+    fn from<S: Step>(kind: Kind) -> StepDescription {
         StepDescription {
             default: S::DEFAULT,
             only_hosts: S::ONLY_HOSTS,
             should_run: S::should_run,
             make_run: S::make_run,
             name: std::any::type_name::<S>(),
+            kind,
         }
     }
 
@@ -177,7 +226,7 @@ impl StepDescription {
     }
 
     fn is_excluded(&self, builder: &Builder<'_>, pathset: &PathSet) -> bool {
-        if builder.config.exclude.iter().any(|e| pathset.has(e)) {
+        if builder.config.exclude.iter().any(|e| pathset.has(&e.path, e.kind)) {
             eprintln!("Skipping {:?} because it is excluded", pathset);
             return true;
         }
@@ -192,8 +241,10 @@ impl StepDescription {
     }
 
     fn run(v: &[StepDescription], builder: &Builder<'_>, paths: &[PathBuf]) {
-        let should_runs =
-            v.iter().map(|desc| (desc.should_run)(ShouldRun::new(builder))).collect::<Vec<_>>();
+        let should_runs = v
+            .iter()
+            .map(|desc| (desc.should_run)(ShouldRun::new(builder, desc.kind)))
+            .collect::<Vec<_>>();
 
         // sanity checks on rules
         for (desc, should_run) in v.iter().zip(&should_runs) {
@@ -226,7 +277,7 @@ impl StepDescription {
                 if let Some(suite) = should_run.is_suite_path(path) {
                     attempted_run = true;
                     desc.maybe_run(builder, suite);
-                } else if let Some(pathset) = should_run.pathset_for_path(path) {
+                } else if let Some(pathset) = should_run.pathset_for_path(path, desc.kind) {
                     attempted_run = true;
                     desc.maybe_run(builder, pathset);
                 }
@@ -246,6 +297,8 @@ enum ReallyDefault<'a> {
 
 pub struct ShouldRun<'a> {
     pub builder: &'a Builder<'a>,
+    kind: Kind,
+
     // use a BTreeSet to maintain sort order
     paths: BTreeSet<PathSet>,
 
@@ -255,9 +308,10 @@ pub struct ShouldRun<'a> {
 }
 
 impl<'a> ShouldRun<'a> {
-    fn new(builder: &'a Builder<'_>) -> ShouldRun<'a> {
+    fn new(builder: &'a Builder<'_>, kind: Kind) -> ShouldRun<'a> {
         ShouldRun {
             builder,
+            kind,
             paths: BTreeSet::new(),
             is_really_default: ReallyDefault::Bool(true), // by default no additional conditions
         }
@@ -293,7 +347,7 @@ impl<'a> ShouldRun<'a> {
         let mut set = BTreeSet::new();
         for krate in self.builder.in_tree_crates(name, None) {
             let path = krate.local_path(self.builder);
-            set.insert(path);
+            set.insert(TaskPath { path, kind: Some(self.kind) });
         }
         self.paths.insert(PathSet::Set(set));
         self
@@ -306,7 +360,7 @@ impl<'a> ShouldRun<'a> {
     pub fn krate(mut self, name: &str) -> Self {
         for krate in self.builder.in_tree_crates(name, None) {
             let path = krate.local_path(self.builder);
-            self.paths.insert(PathSet::one(path));
+            self.paths.insert(PathSet::one(path, self.kind));
         }
         self
     }
@@ -318,19 +372,25 @@ impl<'a> ShouldRun<'a> {
 
     // multiple aliases for the same job
     pub fn paths(mut self, paths: &[&str]) -> Self {
-        self.paths.insert(PathSet::Set(paths.iter().map(PathBuf::from).collect()));
+        self.paths.insert(PathSet::Set(
+            paths
+                .iter()
+                .map(|p| TaskPath { path: p.into(), kind: Some(self.kind.into()) })
+                .collect(),
+        ));
         self
     }
 
     pub fn is_suite_path(&self, path: &Path) -> Option<&PathSet> {
         self.paths.iter().find(|pathset| match pathset {
-            PathSet::Suite(p) => path.starts_with(p),
+            PathSet::Suite(p) => path.starts_with(&p.path),
             PathSet::Set(_) => false,
         })
     }
 
     pub fn suite_path(mut self, suite: &str) -> Self {
-        self.paths.insert(PathSet::Suite(PathBuf::from(suite)));
+        self.paths
+            .insert(PathSet::Suite(TaskPath { path: suite.into(), kind: Some(self.kind.into()) }));
         self
     }
 
@@ -340,12 +400,12 @@ impl<'a> ShouldRun<'a> {
         self
     }
 
-    fn pathset_for_path(&self, path: &Path) -> Option<&PathSet> {
-        self.paths.iter().find(|pathset| pathset.has(path))
+    fn pathset_for_path(&self, path: &Path, kind: Kind) -> Option<&PathSet> {
+        self.paths.iter().find(|pathset| pathset.has(path, Some(kind)))
     }
 }
 
-#[derive(Copy, Clone, PartialEq, Eq, Debug)]
+#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Debug)]
 pub enum Kind {
     Build,
     Check,
@@ -359,11 +419,44 @@ pub enum Kind {
     Run,
 }
 
+impl Kind {
+    fn parse(string: &str) -> Kind {
+        match string {
+            "build" => Kind::Build,
+            "check" => Kind::Check,
+            "clippy" => Kind::Clippy,
+            "fix" => Kind::Fix,
+            "test" => Kind::Test,
+            "bench" => Kind::Bench,
+            "dist" => Kind::Dist,
+            "doc" => Kind::Doc,
+            "install" => Kind::Install,
+            "run" => Kind::Run,
+            other => panic!("unknown kind: {}", other),
+        }
+    }
+
+    fn as_str(&self) -> &'static str {
+        match self {
+            Kind::Build => "build",
+            Kind::Check => "check",
+            Kind::Clippy => "clippy",
+            Kind::Fix => "fix",
+            Kind::Test => "test",
+            Kind::Bench => "bench",
+            Kind::Dist => "dist",
+            Kind::Doc => "doc",
+            Kind::Install => "install",
+            Kind::Run => "run",
+        }
+    }
+}
+
 impl<'a> Builder<'a> {
     fn get_step_descriptions(kind: Kind) -> Vec<StepDescription> {
         macro_rules! describe {
             ($($rule:ty),+ $(,)?) => {{
-                vec![$(StepDescription::from::<$rule>()),+]
+                vec![$(StepDescription::from::<$rule>(kind)),+]
             }};
         }
         match kind {
@@ -540,8 +633,11 @@ impl<'a> Builder<'a> {
 
         let builder = Self::new_internal(build, kind, vec![]);
         let builder = &builder;
-        let mut should_run = ShouldRun::new(builder);
+        // The "build" kind here is just a placeholder, it will be replaced with something else in
+        // the following statement.
+        let mut should_run = ShouldRun::new(builder, Kind::Build);
         for desc in Builder::get_step_descriptions(builder.kind) {
+            should_run.kind = desc.kind;
             should_run = (desc.should_run)(should_run);
         }
         let mut help = String::from("Available paths:\n");
@@ -552,11 +648,11 @@ impl<'a> Builder<'a> {
             match pathset {
                 PathSet::Set(set) => {
                     for path in set {
-                        add_path(&path);
+                        add_path(&path.path);
                     }
                 }
                 PathSet::Suite(path) => {
-                    add_path(&path.join("..."));
+                    add_path(&path.path.join("..."));
                 }
             }
         }
@@ -1626,9 +1722,10 @@ impl<'a> Builder<'a> {
     pub(crate) fn ensure_if_default<T, S: Step<Output = Option<T>>>(
         &'a self,
         step: S,
+        kind: Kind,
     ) -> S::Output {
-        let desc = StepDescription::from::<S>();
-        let should_run = (desc.should_run)(ShouldRun::new(self));
+        let desc = StepDescription::from::<S>(kind);
+        let should_run = (desc.should_run)(ShouldRun::new(self, desc.kind));
 
         // Avoid running steps contained in --exclude
         for pathset in &should_run.paths {
@@ -1642,13 +1739,16 @@ impl<'a> Builder<'a> {
     }
 
     /// Checks if any of the "should_run" paths is in the `Builder` paths.
-    pub(crate) fn was_invoked_explicitly<S: Step>(&'a self) -> bool {
-        let desc = StepDescription::from::<S>();
-        let should_run = (desc.should_run)(ShouldRun::new(self));
+    pub(crate) fn was_invoked_explicitly<S: Step>(&'a self, kind: Kind) -> bool {
+        let desc = StepDescription::from::<S>(kind);
+        let should_run = (desc.should_run)(ShouldRun::new(self, desc.kind));
 
         for path in &self.paths {
-            if should_run.paths.iter().any(|s| s.has(path))
-                && !desc.is_excluded(self, &PathSet::Suite(path.clone()))
+            if should_run.paths.iter().any(|s| s.has(path, Some(desc.kind)))
+                && !desc.is_excluded(
+                    self,
+                    &PathSet::Suite(TaskPath { path: path.clone(), kind: Some(desc.kind.into()) }),
+                )
             {
                 return true;
             }
diff --git a/src/bootstrap/builder/tests.rs b/src/bootstrap/builder/tests.rs
index bb3ea04d4ac..bc710344969 100644
--- a/src/bootstrap/builder/tests.rs
+++ b/src/bootstrap/builder/tests.rs
@@ -499,7 +499,7 @@ mod dist {
         let host = TargetSelection::from_user("A");
 
         builder.run_step_descriptions(
-            &[StepDescription::from::<test::Crate>()],
+            &[StepDescription::from::<test::Crate>(Kind::Test)],
             &["library/std".into()],
         );
 
@@ -520,7 +520,7 @@ mod dist {
     #[test]
     fn test_exclude() {
         let mut config = configure(&["A"], &["A"]);
-        config.exclude = vec!["src/tools/tidy".into()];
+        config.exclude = vec![TaskPath::parse("src/tools/tidy")];
         config.cmd = Subcommand::Test {
             paths: Vec::new(),
             test_args: Vec::new(),
diff --git a/src/bootstrap/config.rs b/src/bootstrap/config.rs
index 5af9248583c..683cfc630e7 100644
--- a/src/bootstrap/config.rs
+++ b/src/bootstrap/config.rs
@@ -12,6 +12,7 @@ use std::fs;
 use std::path::{Path, PathBuf};
 use std::str::FromStr;
 
+use crate::builder::TaskPath;
 use crate::cache::{Interned, INTERNER};
 use crate::channel::GitInfo;
 pub use crate::flags::Subcommand;
@@ -62,7 +63,7 @@ pub struct Config {
     pub sanitizers: bool,
     pub profiler: bool,
     pub ignore_git: bool,
-    pub exclude: Vec<PathBuf>,
+    pub exclude: Vec<TaskPath>,
     pub include_default_paths: bool,
     pub rustc_error_format: Option<String>,
     pub json_output: bool,
@@ -635,7 +636,7 @@ impl Config {
         let flags = Flags::parse(&args);
 
         let mut config = Config::default_opts();
-        config.exclude = flags.exclude;
+        config.exclude = flags.exclude.into_iter().map(|path| TaskPath::parse(path)).collect();
         config.include_default_paths = flags.include_default_paths;
         config.rustc_error_format = flags.rustc_error_format;
         config.json_output = flags.json_output;
diff --git a/src/bootstrap/dist.rs b/src/bootstrap/dist.rs
index a46a4e63714..66b63cd1278 100644
--- a/src/bootstrap/dist.rs
+++ b/src/bootstrap/dist.rs
@@ -16,7 +16,7 @@ use std::process::Command;
 
 use build_helper::{output, t};
 
-use crate::builder::{Builder, RunConfig, ShouldRun, Step};
+use crate::builder::{Builder, Kind, RunConfig, ShouldRun, Step};
 use crate::cache::{Interned, INTERNER};
 use crate::compile;
 use crate::config::TargetSelection;
@@ -1368,7 +1368,7 @@ impl Step for Extended {
         let mut built_tools = HashSet::new();
         macro_rules! add_component {
             ($name:expr => $step:expr) => {
-                if let Some(tarball) = builder.ensure_if_default($step) {
+                if let Some(tarball) = builder.ensure_if_default($step, Kind::Dist) {
                     tarballs.push(tarball);
                     built_tools.insert($name);
                 }
diff --git a/src/bootstrap/doc.rs b/src/bootstrap/doc.rs
index f0f31c447bd..23b5ddcd47a 100644
--- a/src/bootstrap/doc.rs
+++ b/src/bootstrap/doc.rs
@@ -15,7 +15,7 @@ use std::path::{Path, PathBuf};
 use crate::Mode;
 use build_helper::{t, up_to_date};
 
-use crate::builder::{Builder, Compiler, RunConfig, ShouldRun, Step};
+use crate::builder::{Builder, Compiler, Kind, RunConfig, ShouldRun, Step};
 use crate::cache::{Interned, INTERNER};
 use crate::compile;
 use crate::config::{Config, TargetSelection};
@@ -240,7 +240,7 @@ impl Step for TheBook {
             invoke_rustdoc(builder, compiler, target, path);
         }
 
-        if builder.was_invoked_explicitly::<Self>() {
+        if builder.was_invoked_explicitly::<Self>(Kind::Doc) {
             let out = builder.doc_out(target);
             let index = out.join("book").join("index.html");
             open(builder, &index);
@@ -400,7 +400,7 @@ impl Step for Standalone {
 
         // We open doc/index.html as the default if invoked as `x.py doc --open`
         // with no particular explicit doc requested (e.g. library/core).
-        if builder.paths.is_empty() || builder.was_invoked_explicitly::<Self>() {
+        if builder.paths.is_empty() || builder.was_invoked_explicitly::<Self>(Kind::Doc) {
             let index = out.join("index.html");
             open(builder, &index);
         }
@@ -902,7 +902,7 @@ impl Step for RustcBook {
             name: INTERNER.intern_str("rustc"),
             src: INTERNER.intern_path(out_base),
         });
-        if builder.was_invoked_explicitly::<Self>() {
+        if builder.was_invoked_explicitly::<Self>(Kind::Doc) {
             let out = builder.doc_out(self.target);
             let index = out.join("rustc").join("index.html");
             open(builder, &index);
diff --git a/src/librustdoc/html/static/css/rustdoc.css b/src/librustdoc/html/static/css/rustdoc.css
index bdd8aa430b2..2c937aa0ec9 100644
--- a/src/librustdoc/html/static/css/rustdoc.css
+++ b/src/librustdoc/html/static/css/rustdoc.css
@@ -671,7 +671,6 @@ nav.sub {
 	margin: .5em 0;
 	width: calc(100% - 2px);
 	overflow-x: auto;
-	overflow-wrap: normal;
 	display: block;
 }
 
@@ -858,6 +857,31 @@ h2.small-section-header > .anchor {
 
 .block a.current.crate { font-weight: 500; }
 
+/*  In most contexts we use `overflow-wrap: anywhere` to ensure that we can wrap
+	as much as needed on mobile (see
+	src/test/rustdoc-gui/type-declaration-overflow.goml for an example of why
+	this matters). The `anywhere` value means:
+
+	"Soft wrap opportunities introduced by the word break are considered when
+	 calculating min-content intrinsic sizes."
+
+	https://developer.mozilla.org/en-US/docs/Web/CSS/overflow-wrap#values
+
+	For table layouts, that becomes a problem: the browser tries to make each
+	column as narrow as possible, and `overflow-wrap: anywhere` means it can do
+	so by breaking words - even if some other column could be shrunk without
+	breaking words! This shows up, for instance, in the `Structs` / `Modules` /
+	`Functions` (etcetera) sections of a module page, and when a docblock
+	contains a table.
+
+	So, for table layouts, override the default with break-word, which does
+	_not_ affect min-content intrinsic sizes.
+*/
+table,
+.item-table {
+	overflow-wrap: break-word;
+}
+
 .item-table {
 	display: table;
 }
@@ -2058,10 +2082,6 @@ details.rustdoc-toggle[open] > summary.hideme::after {
 		overflow-wrap: anywhere;
 	}
 
-	.docblock table code {
-		overflow-wrap: normal;
-	}
-
 	.sub-container {
 		flex-direction: column;
 	}
diff --git a/src/test/mir-opt/nll/named_lifetimes_basic.use_x.nll.0.mir b/src/test/mir-opt/nll/named_lifetimes_basic.use_x.nll.0.mir
index bfc85e98786..975e2ffbf01 100644
--- a/src/test/mir-opt/nll/named_lifetimes_basic.use_x.nll.0.mir
+++ b/src/test/mir-opt/nll/named_lifetimes_basic.use_x.nll.0.mir
@@ -2,8 +2,8 @@
 
 | Free Region Mapping
 | '_#0r | Global | ['_#2r, '_#1r, '_#0r, '_#4r, '_#3r]
-| '_#1r | External | ['_#1r, '_#4r]
-| '_#2r | External | ['_#2r, '_#1r, '_#4r]
+| '_#1r | Local | ['_#1r, '_#4r]
+| '_#2r | Local | ['_#2r, '_#1r, '_#4r]
 | '_#3r | Local | ['_#4r, '_#3r]
 | '_#4r | Local | ['_#4r]
 |
diff --git a/src/test/rustdoc-gui/src/lib2/lib.rs b/src/test/rustdoc-gui/src/lib2/lib.rs
index 79354ec8745..73013c9778f 100644
--- a/src/test/rustdoc-gui/src/lib2/lib.rs
+++ b/src/test/rustdoc-gui/src/lib2/lib.rs
@@ -39,7 +39,6 @@ impl Trait for Foo {
     const Y: u32 = 0;
 }
 
-
 impl implementors::Whatever for Foo {
     type Foo = u32;
 }
@@ -58,8 +57,10 @@ pub mod sub_mod {
 pub mod long_trait {
     use std::ops::DerefMut;
 
-    pub trait ALongNameBecauseItHelpsTestingTheCurrentProblem: DerefMut<Target = u32>
-        + From<u128> + Send + Sync + AsRef<str> + 'static {}
+    pub trait ALongNameBecauseItHelpsTestingTheCurrentProblem:
+        DerefMut<Target = u32> + From<u128> + Send + Sync + AsRef<str> + 'static
+    {
+    }
 }
 
 pub mod long_table {
@@ -88,18 +89,28 @@ pub mod summary_table {
 }
 
 pub mod too_long {
-pub type ReallyLongTypeNameLongLongLong = Option<unsafe extern "C" fn(a: *const u8, b: *const u8) -> *const u8>;
-
-pub const ReallyLongTypeNameLongLongLongConstBecauseWhyNotAConstRightGigaGigaSupraLong: u32 = 0;
-
-pub struct SuperIncrediblyLongLongLongLongLongLongLongGigaGigaGigaMegaLongLongLongStructName {
-    pub a: u32,
-}
+    pub type ReallyLongTypeNameLongLongLong =
+        Option<unsafe extern "C" fn(a: *const u8, b: *const u8) -> *const u8>;
+
+    pub const ReallyLongTypeNameLongLongLongConstBecauseWhyNotAConstRightGigaGigaSupraLong: u32 = 0;
+
+    /// This also has a really long doccomment. Lorem ipsum dolor sit amet,
+    /// consectetur adipiscing elit. Suspendisse id nibh malesuada, hendrerit
+    /// massa vel, tincidunt est. Nulla interdum, sem ac efficitur ornare, arcu
+    /// nunc dignissim nibh, at rutrum diam augue ac mauris. Fusce tincidunt et
+    /// ligula sed viverra. Aenean sed facilisis dui, non volutpat felis. In
+    /// vitae est dui. Donec felis nibh, blandit at nibh eu, tempor suscipit
+    /// nisl. Vestibulum ornare porta libero, eu faucibus purus iaculis ut. Ut
+    /// quis tincidunt nunc, in mollis purus. Nulla sed interdum quam. Nunc
+    /// vitae cursus ex.
+    pub struct SuperIncrediblyLongLongLongLongLongLongLongGigaGigaGigaMegaLongLongLongStructName {
+        pub a: u32,
+    }
 
-impl SuperIncrediblyLongLongLongLongLongLongLongGigaGigaGigaMegaLongLongLongStructName {
-    /// ```
-    /// let x = SuperIncrediblyLongLongLongLongLongLongLongGigaGigaGigaMegaLongLongLongStructName { a: 0 };
-    /// ```
+    impl SuperIncrediblyLongLongLongLongLongLongLongGigaGigaGigaMegaLongLongLongStructName {
+        /// ```
+        /// let x = SuperIncrediblyLongLongLongLongLongLongLongGigaGigaGigaMegaLongLongLongStructName { a: 0 };
+        /// ```
         pub fn foo(&self) {}
     }
 }
diff --git a/src/test/rustdoc-gui/type-declation-overflow.goml b/src/test/rustdoc-gui/type-declation-overflow.goml
index 21874f786f1..c35b38747df 100644
--- a/src/test/rustdoc-gui/type-declation-overflow.goml
+++ b/src/test/rustdoc-gui/type-declation-overflow.goml
@@ -7,6 +7,10 @@ assert-property: ("body", {"scrollWidth": "1100"})
 // However, since there is overflow in the type declaration, its scroll width is bigger.
 assert-property: (".item-decl pre", {"scrollWidth": "1324"})
 
+// In the table-ish view on the module index, the name should not be wrapped more than necessary.
+goto: file://|DOC_PATH|/lib2/too_long/index.html
+assert-property: (".item-table .struct", {"offsetWidth": "684"})
+
 // We now make the same check on type declaration...
 goto: file://|DOC_PATH|/lib2/too_long/type.ReallyLongTypeNameLongLongLong.html
 assert-property: ("body", {"scrollWidth": "1100"})
diff --git a/src/test/ui/c-variadic/variadic-ffi-4.stderr b/src/test/ui/c-variadic/variadic-ffi-4.stderr
index 4b03fe15494..ff4da5251a9 100644
--- a/src/test/ui/c-variadic/variadic-ffi-4.stderr
+++ b/src/test/ui/c-variadic/variadic-ffi-4.stderr
@@ -20,7 +20,7 @@ LL | pub unsafe extern "C" fn no_escape0<'f>(_: usize, ap: ...) -> VaListImpl<'f
    |                                     |
    |                                     lifetime `'f` defined here
 LL |     ap
-   |     ^^ returning this value requires that `'1` must outlive `'f`
+   |     ^^ function was supposed to return data with lifetime `'f` but it is returning data with lifetime `'1`
    |
    = note: requirement occurs because of the type VaListImpl<'_>, which makes the generic argument '_ invariant
    = note: the struct VaListImpl<'f> is invariant over the parameter 'f
diff --git a/src/test/ui/conditional-compilation/cfg-arg-invalid-1.rs b/src/test/ui/conditional-compilation/cfg-arg-invalid-1.rs
index 36dd78dd2b1..d20e79b9db3 100644
--- a/src/test/ui/conditional-compilation/cfg-arg-invalid-1.rs
+++ b/src/test/ui/conditional-compilation/cfg-arg-invalid-1.rs
@@ -1,3 +1,3 @@
 // compile-flags: --cfg a(b=c)
-// error-pattern: invalid `--cfg` argument: `a(b=c)` (expected `key` or `key="value"`)
+// error-pattern: invalid `--cfg` argument: `a(b=c)` (expected `key` or `key="value"`, ensure escaping is appropriate for your shell, try 'key="value"' or key=\"value\")
 fn main() {}
diff --git a/src/test/ui/conditional-compilation/cfg-arg-invalid-1.stderr b/src/test/ui/conditional-compilation/cfg-arg-invalid-1.stderr
index 1e7922a9ff1..3a12e978680 100644
--- a/src/test/ui/conditional-compilation/cfg-arg-invalid-1.stderr
+++ b/src/test/ui/conditional-compilation/cfg-arg-invalid-1.stderr
@@ -1,2 +1,2 @@
-error: invalid `--cfg` argument: `a(b=c)` (expected `key` or `key="value"`)
+error: invalid `--cfg` argument: `a(b=c)` (expected `key` or `key="value"`, ensure escaping is appropriate for your shell, try 'key="value"' or key=\"value\")
 
diff --git a/src/test/ui/conditional-compilation/cfg-arg-invalid-9.rs b/src/test/ui/conditional-compilation/cfg-arg-invalid-9.rs
new file mode 100644
index 00000000000..628b335c873
--- /dev/null
+++ b/src/test/ui/conditional-compilation/cfg-arg-invalid-9.rs
@@ -0,0 +1,4 @@
+// Test for missing quotes around value, issue #66450.
+// compile-flags: --cfg key=value
+// error-pattern: invalid `--cfg` argument: `key=value` (expected `key` or `key="value"`, ensure escaping is appropriate for your shell, try 'key="value"' or key=\"value\")
+fn main() {}
diff --git a/src/test/ui/conditional-compilation/cfg-arg-invalid-9.stderr b/src/test/ui/conditional-compilation/cfg-arg-invalid-9.stderr
new file mode 100644
index 00000000000..985b5252258
--- /dev/null
+++ b/src/test/ui/conditional-compilation/cfg-arg-invalid-9.stderr
@@ -0,0 +1,2 @@
+error: invalid `--cfg` argument: `key=value` (expected `key` or `key="value"`, ensure escaping is appropriate for your shell, try 'key="value"' or key=\"value\")
+
diff --git a/src/test/ui/fn/implied-bounds-unnorm-associated-type.nll.stderr b/src/test/ui/fn/implied-bounds-unnorm-associated-type.nll.stderr
index e37ec7f2665..8096f08385c 100644
--- a/src/test/ui/fn/implied-bounds-unnorm-associated-type.nll.stderr
+++ b/src/test/ui/fn/implied-bounds-unnorm-associated-type.nll.stderr
@@ -6,7 +6,7 @@ LL | fn f<'a, 'b>(s: &'b str, _: <&'a &'b () as Trait>::Type) -> &'a str {
    |      |
    |      lifetime `'a` defined here
 LL |     s
-   |     ^ returning this value requires that `'b` must outlive `'a`
+   |     ^ function was supposed to return data with lifetime `'a` but it is returning data with lifetime `'b`
    |
    = help: consider adding the following bound: `'b: 'a`
 
diff --git a/src/test/ui/issues/issue-16683.nll.stderr b/src/test/ui/issues/issue-16683.nll.stderr
index 0e8f520353f..fff681b2e0b 100644
--- a/src/test/ui/issues/issue-16683.nll.stderr
+++ b/src/test/ui/issues/issue-16683.nll.stderr
@@ -1,20 +1,13 @@
-error[E0521]: borrowed data escapes outside of associated function
+error: lifetime may not live long enough
   --> $DIR/issue-16683.rs:4:9
    |
 LL | trait T<'a> {
    |         -- lifetime `'a` defined here
 LL |     fn a(&'a self) -> &'a bool;
 LL |     fn b(&self) {
-   |          -----
-   |          |
-   |          `self` is a reference that is only valid in the associated function body
-   |          let's call the lifetime of this reference `'1`
+   |          - let's call the lifetime of this reference `'1`
 LL |         self.a();
-   |         ^^^^^^^^
-   |         |
-   |         `self` escapes the associated function body here
-   |         argument requires that `'1` must outlive `'a`
+   |         ^^^^^^^^ argument requires that `'1` must outlive `'a`
 
 error: aborting due to previous error
 
-For more information about this error, try `rustc --explain E0521`.
diff --git a/src/test/ui/issues/issue-17758.nll.stderr b/src/test/ui/issues/issue-17758.nll.stderr
index b929fdbf368..613ef6b907c 100644
--- a/src/test/ui/issues/issue-17758.nll.stderr
+++ b/src/test/ui/issues/issue-17758.nll.stderr
@@ -1,20 +1,13 @@
-error[E0521]: borrowed data escapes outside of associated function
+error: lifetime may not live long enough
   --> $DIR/issue-17758.rs:7:9
    |
 LL | trait Foo<'a> {
    |           -- lifetime `'a` defined here
 LL |     fn foo(&'a self);
 LL |     fn bar(&self) {
-   |            -----
-   |            |
-   |            `self` is a reference that is only valid in the associated function body
-   |            let's call the lifetime of this reference `'1`
+   |            - let's call the lifetime of this reference `'1`
 LL |         self.foo();
-   |         ^^^^^^^^^^
-   |         |
-   |         `self` escapes the associated function body here
-   |         argument requires that `'1` must outlive `'a`
+   |         ^^^^^^^^^^ argument requires that `'1` must outlive `'a`
 
 error: aborting due to previous error
 
-For more information about this error, try `rustc --explain E0521`.
diff --git a/src/test/ui/issues/issue-47377.stderr b/src/test/ui/issues/issue-47377.stderr
index a7b8b1ca861..4f0fd948e76 100644
--- a/src/test/ui/issues/issue-47377.stderr
+++ b/src/test/ui/issues/issue-47377.stderr
@@ -7,10 +7,11 @@ LL |      let _a = b + ", World!";
    |               | `+` cannot be used to concatenate two `&str` strings
    |               &str
    |
-help: `to_owned()` can be used to create an owned `String` from a string reference. String concatenation appends the string on the right to the string on the left and may require reallocation. This requires ownership of the string on the left
+   = note: string concatenation requires an owned `String` on the left
+help: create an owned `String` from a string reference
    |
 LL |      let _a = b.to_owned() + ", World!";
-   |               ~~~~~~~~~~~~
+   |                +++++++++++
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/issues/issue-47380.stderr b/src/test/ui/issues/issue-47380.stderr
index f6222c77e2e..b04ac5536c4 100644
--- a/src/test/ui/issues/issue-47380.stderr
+++ b/src/test/ui/issues/issue-47380.stderr
@@ -7,10 +7,11 @@ LL |     println!("🦀🦀🦀🦀🦀"); let _a = b + ", World!";
    |                                      | `+` cannot be used to concatenate two `&str` strings
    |                                      &str
    |
-help: `to_owned()` can be used to create an owned `String` from a string reference. String concatenation appends the string on the right to the string on the left and may require reallocation. This requires ownership of the string on the left
+   = note: string concatenation requires an owned `String` on the left
+help: create an owned `String` from a string reference
    |
 LL |     println!("🦀🦀🦀🦀🦀"); let _a = b.to_owned() + ", World!";
-   |                                      ~~~~~~~~~~~~
+   |                                       +++++++++++
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/issues/issue-5100.stderr b/src/test/ui/issues/issue-5100.stderr
index de71e1d1a66..c87a3e348a2 100644
--- a/src/test/ui/issues/issue-5100.stderr
+++ b/src/test/ui/issues/issue-5100.stderr
@@ -59,10 +59,8 @@ LL |         &(true, false) => ()
 error[E0618]: expected function, found `(char, char)`
   --> $DIR/issue-5100.rs:48:14
    |
-LL |       let v = [('a', 'b')
-   |  ______________-^^^^^^^^^
-LL | |              ('c', 'd'),
-   | |_______________________- call expression requires function
+LL |     let v = [('a', 'b')
+   |              ^^^^^^^^^^- help: consider separating array elements with a comma: `,`
 
 error[E0308]: mismatched types
   --> $DIR/issue-5100.rs:55:19
diff --git a/src/test/ui/issues/issue-52213.nll.stderr b/src/test/ui/issues/issue-52213.nll.stderr
index 359f91309d4..da31bcd5475 100644
--- a/src/test/ui/issues/issue-52213.nll.stderr
+++ b/src/test/ui/issues/issue-52213.nll.stderr
@@ -7,7 +7,7 @@ LL | fn transmute_lifetime<'a, 'b, T>(t: &'a (T,)) -> &'b T {
    |                       lifetime `'a` defined here
 LL |     match (&t,) {
 LL |         ((u,),) => u,
-   |                    ^ returning this value requires that `'a` must outlive `'b`
+   |                    ^ function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a`
    |
    = help: consider adding the following bound: `'a: 'b`
 
diff --git a/src/test/ui/match/match-ref-mut-invariance.nll.stderr b/src/test/ui/match/match-ref-mut-invariance.nll.stderr
index 1dc29d2088c..c8a7876dc54 100644
--- a/src/test/ui/match/match-ref-mut-invariance.nll.stderr
+++ b/src/test/ui/match/match-ref-mut-invariance.nll.stderr
@@ -6,7 +6,7 @@ LL | impl<'b> S<'b> {
 LL |     fn bar<'a>(&'a mut self) -> &'a mut &'a i32 {
    |            -- lifetime `'a` defined here
 LL |         match self.0 { ref mut x => x }
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ returning this value requires that `'a` must outlive `'b`
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ associated function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a`
    |
    = help: consider adding the following bound: `'a: 'b`
    = note: requirement occurs because of a mutable reference to &i32
diff --git a/src/test/ui/match/match-ref-mut-let-invariance.nll.stderr b/src/test/ui/match/match-ref-mut-let-invariance.nll.stderr
index 8b87c3da28b..11ddf1487dd 100644
--- a/src/test/ui/match/match-ref-mut-let-invariance.nll.stderr
+++ b/src/test/ui/match/match-ref-mut-let-invariance.nll.stderr
@@ -7,7 +7,7 @@ LL |     fn bar<'a>(&'a mut self) -> &'a mut &'a i32 {
    |            -- lifetime `'a` defined here
 LL |         let ref mut x = self.0;
 LL |         x
-   |         ^ returning this value requires that `'a` must outlive `'b`
+   |         ^ associated function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a`
    |
    = help: consider adding the following bound: `'a: 'b`
    = note: requirement occurs because of a mutable reference to &i32
diff --git a/src/test/ui/nll/issue-52113.stderr b/src/test/ui/nll/issue-52113.stderr
index dcf03386734..f70ae2edd7f 100644
--- a/src/test/ui/nll/issue-52113.stderr
+++ b/src/test/ui/nll/issue-52113.stderr
@@ -7,7 +7,7 @@ LL | fn produce_err<'a, 'b: 'a>(data: &'b mut Vec<&'b u32>, value: &'a u32) -> i
    |                lifetime `'a` defined here
 ...
 LL |     x
-   |     ^ returning this value requires that `'a` must outlive `'b`
+   |     ^ function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a`
    |
    = help: consider adding the following bound: `'a: 'b`
 
diff --git a/src/test/ui/nll/issue-55394.nll.stderr b/src/test/ui/nll/issue-55394.nll.stderr
index d0723047ac0..24b8c84b4a9 100644
--- a/src/test/ui/nll/issue-55394.nll.stderr
+++ b/src/test/ui/nll/issue-55394.nll.stderr
@@ -6,7 +6,7 @@ LL |     fn new(bar: &mut Bar) -> Self {
    |                 |
    |                 let's call the lifetime of this reference `'1`
 LL |         Foo { bar }
-   |         ^^^^^^^^^^^ returning this value requires that `'1` must outlive `'2`
+   |         ^^^^^^^^^^^ associated function was supposed to return data with lifetime `'2` but it is returning data with lifetime `'1`
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/nll/issue-67007-escaping-data.rs b/src/test/ui/nll/issue-67007-escaping-data.rs
index 8c21737e05f..99b6d512261 100644
--- a/src/test/ui/nll/issue-67007-escaping-data.rs
+++ b/src/test/ui/nll/issue-67007-escaping-data.rs
@@ -14,7 +14,7 @@ struct Consumer<'tcx>(&'tcx ());
 
 impl<'tcx> Consumer<'tcx> {
     fn bad_method<'a>(&self, fcx: &FnCtxt<'a, 'tcx>) {
-        let other = self.use_fcx(fcx); //~ ERROR borrowed data
+        let other = self.use_fcx(fcx); //~ ERROR lifetime may not live long enough
         fcx.use_it(other);
     }
 
diff --git a/src/test/ui/nll/issue-67007-escaping-data.stderr b/src/test/ui/nll/issue-67007-escaping-data.stderr
index 2834d6fb0d2..ce067e23aa3 100644
--- a/src/test/ui/nll/issue-67007-escaping-data.stderr
+++ b/src/test/ui/nll/issue-67007-escaping-data.stderr
@@ -1,21 +1,14 @@
-error[E0521]: borrowed data escapes outside of associated function
+error: lifetime may not live long enough
   --> $DIR/issue-67007-escaping-data.rs:17:21
    |
 LL | impl<'tcx> Consumer<'tcx> {
    |      ---- lifetime `'tcx` defined here
 LL |     fn bad_method<'a>(&self, fcx: &FnCtxt<'a, 'tcx>) {
-   |                   --  -----  --- `fcx` is a reference that is only valid in the associated function body
-   |                   |   |
-   |                   |   `self` declared here, outside of the associated function body
-   |                   lifetime `'a` defined here
+   |                   -- lifetime `'a` defined here
 LL |         let other = self.use_fcx(fcx);
-   |                     ^^^^^^^^^^^^^^^^^
-   |                     |
-   |                     `fcx` escapes the associated function body here
-   |                     argument requires that `'a` must outlive `'tcx`
+   |                     ^^^^^^^^^^^^^^^^^ argument requires that `'a` must outlive `'tcx`
    |
    = help: consider adding the following bound: `'a: 'tcx`
 
 error: aborting due to previous error
 
-For more information about this error, try `rustc --explain E0521`.
diff --git a/src/test/ui/nll/mir_check_cast_closure.stderr b/src/test/ui/nll/mir_check_cast_closure.stderr
index 113e220e513..f34cafe308d 100644
--- a/src/test/ui/nll/mir_check_cast_closure.stderr
+++ b/src/test/ui/nll/mir_check_cast_closure.stderr
@@ -7,7 +7,7 @@ LL | fn bar<'a, 'b>() -> fn(&'a u32, &'b u32) -> &'a u32 {
    |        lifetime `'a` defined here
 LL |     let g: fn(_, _) -> _ = |_x, y| y;
 LL |     g
-   |     ^ returning this value requires that `'b` must outlive `'a`
+   |     ^ function was supposed to return data with lifetime `'a` but it is returning data with lifetime `'b`
    |
    = help: consider adding the following bound: `'b: 'a`
 
diff --git a/src/test/ui/nll/outlives-suggestion-more.stderr b/src/test/ui/nll/outlives-suggestion-more.stderr
index a80e59d4822..7f98aa5801d 100644
--- a/src/test/ui/nll/outlives-suggestion-more.stderr
+++ b/src/test/ui/nll/outlives-suggestion-more.stderr
@@ -6,7 +6,7 @@ LL | fn foo1<'a, 'b, 'c, 'd>(x: &'a usize, y: &'b usize) -> (&'c usize, &'d usiz
    |         |
    |         lifetime `'a` defined here
 LL |     (x, y)
-   |     ^^^^^^ returning this value requires that `'a` must outlive `'c`
+   |     ^^^^^^ function was supposed to return data with lifetime `'c` but it is returning data with lifetime `'a`
    |
    = help: consider adding the following bound: `'a: 'c`
 
@@ -18,7 +18,7 @@ LL | fn foo1<'a, 'b, 'c, 'd>(x: &'a usize, y: &'b usize) -> (&'c usize, &'d usiz
    |             |
    |             lifetime `'b` defined here
 LL |     (x, y)
-   |     ^^^^^^ returning this value requires that `'b` must outlive `'d`
+   |     ^^^^^^ function was supposed to return data with lifetime `'d` but it is returning data with lifetime `'b`
    |
    = help: consider adding the following bound: `'b: 'd`
 
@@ -35,7 +35,7 @@ LL | fn foo2<'a, 'b, 'c>(x: &'a usize, y: &'b usize) -> (&'c usize, &'static usi
    |         |
    |         lifetime `'a` defined here
 LL |     (x, y)
-   |     ^^^^^^ returning this value requires that `'a` must outlive `'c`
+   |     ^^^^^^ function was supposed to return data with lifetime `'c` but it is returning data with lifetime `'a`
    |
    = help: consider adding the following bound: `'a: 'c`
 
diff --git a/src/test/ui/nll/outlives-suggestion-simple.rs b/src/test/ui/nll/outlives-suggestion-simple.rs
index 41e4d83aa92..496cf92400c 100644
--- a/src/test/ui/nll/outlives-suggestion-simple.rs
+++ b/src/test/ui/nll/outlives-suggestion-simple.rs
@@ -70,7 +70,7 @@ pub struct Foo2<'a> {
 impl<'a> Foo2<'a> {
     // should not produce outlives suggestions to name 'self
     fn get_bar(&self) -> Bar2 {
-        Bar2::new(&self) //~ERROR borrowed data escapes outside of associated function
+        Bar2::new(&self) //~ERROR lifetime may not live long enough
     }
 }
 
diff --git a/src/test/ui/nll/outlives-suggestion-simple.stderr b/src/test/ui/nll/outlives-suggestion-simple.stderr
index 3b2017d2d03..8e6e4f1a476 100644
--- a/src/test/ui/nll/outlives-suggestion-simple.stderr
+++ b/src/test/ui/nll/outlives-suggestion-simple.stderr
@@ -6,7 +6,7 @@ LL | fn foo1<'a, 'b>(x: &'a usize) -> &'b usize {
    |         |
    |         lifetime `'a` defined here
 LL |     x
-   |     ^ returning this value requires that `'a` must outlive `'b`
+   |     ^ function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a`
    |
    = help: consider adding the following bound: `'a: 'b`
 
@@ -53,7 +53,7 @@ LL | fn foo4<'a, 'b, 'c>(x: &'a usize) -> (&'b usize, &'c usize) {
    |         lifetime `'a` defined here
 ...
 LL |     (x, x)
-   |     ^^^^^^ returning this value requires that `'a` must outlive `'b`
+   |     ^^^^^^ function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a`
    |
    = help: consider adding the following bound: `'a: 'b`
 
@@ -73,7 +73,7 @@ LL | impl<'a> Bar<'a> {
 LL |     pub fn get<'b>(&self) -> &'b usize {
    |                -- lifetime `'b` defined here
 LL |         self.x
-   |         ^^^^^^ returning this value requires that `'a` must outlive `'b`
+   |         ^^^^^^ associated function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a`
    |
    = help: consider adding the following bound: `'a: 'b`
 
@@ -85,28 +85,20 @@ LL | impl<'a> Baz<'a> {
 LL |     fn get<'b>(&'b self) -> &'a i32 {
    |            -- lifetime `'b` defined here
 LL |         self.x
-   |         ^^^^^^ returning this value requires that `'b` must outlive `'a`
+   |         ^^^^^^ associated function was supposed to return data with lifetime `'a` but it is returning data with lifetime `'b`
    |
    = help: consider adding the following bound: `'b: 'a`
 
-error[E0521]: borrowed data escapes outside of associated function
+error: lifetime may not live long enough
   --> $DIR/outlives-suggestion-simple.rs:73:9
    |
 LL | impl<'a> Foo2<'a> {
    |      -- lifetime `'a` defined here
 LL |     // should not produce outlives suggestions to name 'self
 LL |     fn get_bar(&self) -> Bar2 {
-   |                -----
-   |                |
-   |                `self` declared here, outside of the associated function body
-   |                `self` is a reference that is only valid in the associated function body
-   |                let's call the lifetime of this reference `'1`
+   |                - let's call the lifetime of this reference `'1`
 LL |         Bar2::new(&self)
-   |         ^^^^^^^^^^^^^^^^
-   |         |
-   |         `self` escapes the associated function body here
-   |         argument requires that `'1` must outlive `'a`
+   |         ^^^^^^^^^^^^^^^^ argument requires that `'1` must outlive `'a`
 
 error: aborting due to 9 previous errors
 
-For more information about this error, try `rustc --explain E0521`.
diff --git a/src/test/ui/nll/type-alias-free-regions.nll.stderr b/src/test/ui/nll/type-alias-free-regions.nll.stderr
index bde73b05894..45fd5a2f1d6 100644
--- a/src/test/ui/nll/type-alias-free-regions.nll.stderr
+++ b/src/test/ui/nll/type-alias-free-regions.nll.stderr
@@ -6,7 +6,7 @@ LL | impl<'a> FromBox<'a> for C<'a> {
 LL |     fn from_box(b: Box<B>) -> Self {
    |                 - has type `Box<Box<&'1 isize>>`
 LL |         C { f: b }
-   |         ^^^^^^^^^^ returning this value requires that `'1` must outlive `'a`
+   |         ^^^^^^^^^^ associated function was supposed to return data with lifetime `'a` but it is returning data with lifetime `'1`
 
 error: lifetime may not live long enough
   --> $DIR/type-alias-free-regions.rs:27:9
@@ -16,7 +16,7 @@ LL | impl<'a> FromTuple<'a> for C<'a> {
 LL |     fn from_tuple(b: (B,)) -> Self {
    |                   - has type `(Box<&'1 isize>,)`
 LL |         C { f: Box::new(b.0) }
-   |         ^^^^^^^^^^^^^^^^^^^^^^ returning this value requires that `'1` must outlive `'a`
+   |         ^^^^^^^^^^^^^^^^^^^^^^ associated function was supposed to return data with lifetime `'a` but it is returning data with lifetime `'1`
 
 error: aborting due to 2 previous errors
 
diff --git a/src/test/ui/nll/type-check-pointer-coercions.stderr b/src/test/ui/nll/type-check-pointer-coercions.stderr
index ccb3d33ac40..b392c2007d3 100644
--- a/src/test/ui/nll/type-check-pointer-coercions.stderr
+++ b/src/test/ui/nll/type-check-pointer-coercions.stderr
@@ -6,7 +6,7 @@ LL | fn shared_to_const<'a, 'b>(x: &&'a i32) -> *const &'b i32 {
    |                    |
    |                    lifetime `'a` defined here
 LL |     x
-   |     ^ returning this value requires that `'a` must outlive `'b`
+   |     ^ function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a`
    |
    = help: consider adding the following bound: `'a: 'b`
 
@@ -18,7 +18,7 @@ LL | fn unique_to_const<'a, 'b>(x: &mut &'a i32) -> *const &'b i32 {
    |                    |
    |                    lifetime `'a` defined here
 LL |     x
-   |     ^ returning this value requires that `'a` must outlive `'b`
+   |     ^ function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a`
    |
    = help: consider adding the following bound: `'a: 'b`
 
@@ -47,7 +47,7 @@ LL | fn unique_to_mut<'a, 'b>(x: &mut &'a i32) -> *mut &'b i32 {
    |                  lifetime `'a` defined here
 LL |     // Two errors because *mut is invariant
 LL |     x
-   |     ^ returning this value requires that `'a` must outlive `'b`
+   |     ^ function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a`
    |
    = help: consider adding the following bound: `'a: 'b`
    = note: requirement occurs because of a mutable pointer to &i32
@@ -64,7 +64,7 @@ LL | fn mut_to_const<'a, 'b>(x: *mut &'a i32) -> *const &'b i32 {
    |                 |
    |                 lifetime `'a` defined here
 LL |     x
-   |     ^ returning this value requires that `'a` must outlive `'b`
+   |     ^ function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a`
    |
    = help: consider adding the following bound: `'a: 'b`
 
@@ -77,7 +77,7 @@ LL | fn array_elem<'a, 'b>(x: &'a i32) -> *const &'b i32 {
    |               lifetime `'a` defined here
 ...
 LL |     y
-   |     ^ returning this value requires that `'a` must outlive `'b`
+   |     ^ function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a`
    |
    = help: consider adding the following bound: `'a: 'b`
 
@@ -90,7 +90,7 @@ LL | fn array_coerce<'a, 'b>(x: &'a i32) -> *const [&'b i32; 3] {
    |                 lifetime `'a` defined here
 ...
 LL |     y
-   |     ^ returning this value requires that `'a` must outlive `'b`
+   |     ^ function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a`
    |
    = help: consider adding the following bound: `'a: 'b`
 
@@ -103,7 +103,7 @@ LL | fn nested_array<'a, 'b>(x: &'a i32) -> *const [&'b i32; 2] {
    |                 lifetime `'a` defined here
 ...
 LL |     y
-   |     ^ returning this value requires that `'a` must outlive `'b`
+   |     ^ function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a`
    |
    = help: consider adding the following bound: `'a: 'b`
 
diff --git a/src/test/ui/nll/user-annotations/wf-self-type.stderr b/src/test/ui/nll/user-annotations/wf-self-type.stderr
index 33bb1c519b1..902b4c68755 100644
--- a/src/test/ui/nll/user-annotations/wf-self-type.stderr
+++ b/src/test/ui/nll/user-annotations/wf-self-type.stderr
@@ -6,7 +6,7 @@ LL | pub fn foo<'a, 'b>(u: &'b ()) -> &'a () {
    |            |
    |            lifetime `'a` defined here
 LL |     Foo::xmute(u)
-   |     ^^^^^^^^^^^^^ returning this value requires that `'b` must outlive `'a`
+   |     ^^^^^^^^^^^^^ function was supposed to return data with lifetime `'a` but it is returning data with lifetime `'b`
    |
    = help: consider adding the following bound: `'b: 'a`
 
diff --git a/src/test/ui/object-lifetime/object-lifetime-default-elision.nll.stderr b/src/test/ui/object-lifetime/object-lifetime-default-elision.nll.stderr
index 900cdfca244..61e96f59fed 100644
--- a/src/test/ui/object-lifetime/object-lifetime-default-elision.nll.stderr
+++ b/src/test/ui/object-lifetime/object-lifetime-default-elision.nll.stderr
@@ -7,7 +7,7 @@ LL | fn load3<'a,'b>(ss: &'a dyn SomeTrait) -> &'b dyn SomeTrait {
    |          lifetime `'a` defined here
 ...
 LL |     ss
-   |     ^^ returning this value requires that `'a` must outlive `'b`
+   |     ^^ function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a`
    |
    = help: consider adding the following bound: `'a: 'b`
 
diff --git a/src/test/ui/regions/region-object-lifetime-2.nll.stderr b/src/test/ui/regions/region-object-lifetime-2.nll.stderr
index db45a03ad18..d95289f3f9d 100644
--- a/src/test/ui/regions/region-object-lifetime-2.nll.stderr
+++ b/src/test/ui/regions/region-object-lifetime-2.nll.stderr
@@ -6,7 +6,7 @@ LL | fn borrowed_receiver_different_lifetimes<'a,'b>(x: &'a dyn Foo) -> &'b () {
    |                                          |
    |                                          lifetime `'a` defined here
 LL |     x.borrowed()
-   |     ^^^^^^^^^^^^ returning this value requires that `'a` must outlive `'b`
+   |     ^^^^^^^^^^^^ function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a`
    |
    = help: consider adding the following bound: `'a: 'b`
 
diff --git a/src/test/ui/regions/region-object-lifetime-in-coercion.nll.stderr b/src/test/ui/regions/region-object-lifetime-in-coercion.nll.stderr
index 7e8f78067e0..92588819076 100644
--- a/src/test/ui/regions/region-object-lifetime-in-coercion.nll.stderr
+++ b/src/test/ui/regions/region-object-lifetime-in-coercion.nll.stderr
@@ -31,7 +31,7 @@ LL | fn d<'a,'b>(v: &'a [u8]) -> Box<dyn Foo+'b> {
    |      |
    |      lifetime `'a` defined here
 LL |     Box::new(v)
-   |     ^^^^^^^^^^^ returning this value requires that `'a` must outlive `'b`
+   |     ^^^^^^^^^^^ function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a`
    |
    = help: consider adding the following bound: `'a: 'b`
 
diff --git a/src/test/ui/regions/regions-bounded-method-type-parameters-trait-bound.nll.stderr b/src/test/ui/regions/regions-bounded-method-type-parameters-trait-bound.nll.stderr
index 62032bcb609..246b6483c21 100644
--- a/src/test/ui/regions/regions-bounded-method-type-parameters-trait-bound.nll.stderr
+++ b/src/test/ui/regions/regions-bounded-method-type-parameters-trait-bound.nll.stderr
@@ -1,18 +1,13 @@
-error[E0521]: borrowed data escapes outside of function
+error: lifetime may not live long enough
   --> $DIR/regions-bounded-method-type-parameters-trait-bound.rs:20:5
    |
 LL | fn caller2<'a,'b,F:Foo<'a>>(a: Inv<'a>, b: Inv<'b>, f: F) {
-   |            -- --            -           - `b` is a reference that is only valid in the function body
-   |            |  |             |
-   |            |  |             `a` declared here, outside of the function body
-   |            |  lifetime `'b` defined here
+   |            -- -- lifetime `'b` defined here
+   |            |
    |            lifetime `'a` defined here
 LL |     // Here the value provided for 'y is 'b, and hence 'b:'a does not hold.
 LL |     f.method(b);
-   |     ^^^^^^^^^^^
-   |     |
-   |     `b` escapes the function body here
-   |     argument requires that `'b` must outlive `'a`
+   |     ^^^^^^^^^^^ argument requires that `'b` must outlive `'a`
    |
    = help: consider adding the following bound: `'b: 'a`
    = note: requirement occurs because of the type Inv<'_>, which makes the generic argument '_ invariant
@@ -21,4 +16,3 @@ LL |     f.method(b);
 
 error: aborting due to previous error
 
-For more information about this error, try `rustc --explain E0521`.
diff --git a/src/test/ui/regions/regions-bounds.nll.stderr b/src/test/ui/regions/regions-bounds.nll.stderr
index dd702755c7e..84226a57553 100644
--- a/src/test/ui/regions/regions-bounds.nll.stderr
+++ b/src/test/ui/regions/regions-bounds.nll.stderr
@@ -6,7 +6,7 @@ LL | fn a_fn1<'a,'b>(e: TupleStruct<'a>) -> TupleStruct<'b> {
    |          |
    |          lifetime `'a` defined here
 LL |     return e;
-   |            ^ returning this value requires that `'a` must outlive `'b`
+   |            ^ function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a`
    |
    = help: consider adding the following bound: `'a: 'b`
 
@@ -18,7 +18,7 @@ LL | fn a_fn3<'a,'b>(e: Struct<'a>) -> Struct<'b> {
    |          |
    |          lifetime `'a` defined here
 LL |     return e;
-   |            ^ returning this value requires that `'a` must outlive `'b`
+   |            ^ function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a`
    |
    = help: consider adding the following bound: `'a: 'b`
 
diff --git a/src/test/ui/regions/regions-close-over-type-parameter-multiple.nll.stderr b/src/test/ui/regions/regions-close-over-type-parameter-multiple.nll.stderr
index c2bd3bbf823..25566742099 100644
--- a/src/test/ui/regions/regions-close-over-type-parameter-multiple.nll.stderr
+++ b/src/test/ui/regions/regions-close-over-type-parameter-multiple.nll.stderr
@@ -7,7 +7,7 @@ LL | fn make_object_bad<'a,'b,'c,A:SomeTrait+'a+'b>(v: A) -> Box<dyn SomeTrait +
    |                    lifetime `'a` defined here
 LL |     // A outlives 'a AND 'b...but not 'c.
 LL |     Box::new(v) as Box<dyn SomeTrait + 'a>
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ returning this value requires that `'a` must outlive `'c`
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ function was supposed to return data with lifetime `'c` but it is returning data with lifetime `'a`
    |
    = help: consider adding the following bound: `'a: 'c`
 
diff --git a/src/test/ui/regions/regions-creating-enums4.nll.stderr b/src/test/ui/regions/regions-creating-enums4.nll.stderr
index dda374c90d9..91cf57e099d 100644
--- a/src/test/ui/regions/regions-creating-enums4.nll.stderr
+++ b/src/test/ui/regions/regions-creating-enums4.nll.stderr
@@ -6,7 +6,7 @@ LL | fn mk_add_bad2<'a,'b>(x: &'a Ast<'a>, y: &'a Ast<'a>, z: &Ast) -> Ast<'b> {
    |                |
    |                lifetime `'a` defined here
 LL |     Ast::Add(x, y)
-   |     ^^^^^^^^^^^^^^ returning this value requires that `'a` must outlive `'b`
+   |     ^^^^^^^^^^^^^^ function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a`
    |
    = help: consider adding the following bound: `'a: 'b`
 
diff --git a/src/test/ui/regions/regions-early-bound-error-method.nll.stderr b/src/test/ui/regions/regions-early-bound-error-method.nll.stderr
index 4957bcf3f73..7f10c051f29 100644
--- a/src/test/ui/regions/regions-early-bound-error-method.nll.stderr
+++ b/src/test/ui/regions/regions-early-bound-error-method.nll.stderr
@@ -6,7 +6,7 @@ LL | impl<'a> Box<'a> {
 LL |     fn or<'b,G:GetRef<'b>>(&self, g2: G) -> &'a isize {
    |           -- lifetime `'b` defined here
 LL |         g2.get()
-   |         ^^^^^^^^ returning this value requires that `'b` must outlive `'a`
+   |         ^^^^^^^^ associated function was supposed to return data with lifetime `'a` but it is returning data with lifetime `'b`
    |
    = help: consider adding the following bound: `'b: 'a`
 
diff --git a/src/test/ui/regions/regions-free-region-ordering-incorrect.nll.stderr b/src/test/ui/regions/regions-free-region-ordering-incorrect.nll.stderr
index 106d3df2744..f7c75033c04 100644
--- a/src/test/ui/regions/regions-free-region-ordering-incorrect.nll.stderr
+++ b/src/test/ui/regions/regions-free-region-ordering-incorrect.nll.stderr
@@ -9,7 +9,7 @@ LL | /         match self.next {
 LL | |             Some(ref next) => next.get(),
 LL | |             None => &self.val
 LL | |         }
-   | |_________^ returning this value requires that `'a` must outlive `'b`
+   | |_________^ associated function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a`
    |
    = help: consider adding the following bound: `'a: 'b`
 
diff --git a/src/test/ui/regions/regions-infer-not-param.nll.stderr b/src/test/ui/regions/regions-infer-not-param.nll.stderr
index e211f9d1391..3183aee23d9 100644
--- a/src/test/ui/regions/regions-infer-not-param.nll.stderr
+++ b/src/test/ui/regions/regions-infer-not-param.nll.stderr
@@ -2,7 +2,7 @@ error: lifetime may not live long enough
   --> $DIR/regions-infer-not-param.rs:15:54
    |
 LL | fn take_direct<'a,'b>(p: Direct<'a>) -> Direct<'b> { p }
-   |                -- -- lifetime `'b` defined here      ^ returning this value requires that `'a` must outlive `'b`
+   |                -- -- lifetime `'b` defined here      ^ function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a`
    |                |
    |                lifetime `'a` defined here
    |
@@ -25,7 +25,7 @@ error: lifetime may not live long enough
   --> $DIR/regions-infer-not-param.rs:19:63
    |
 LL | fn take_indirect2<'a,'b>(p: Indirect2<'a>) -> Indirect2<'b> { p }
-   |                   -- -- lifetime `'b` defined here            ^ returning this value requires that `'a` must outlive `'b`
+   |                   -- -- lifetime `'b` defined here            ^ function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a`
    |                   |
    |                   lifetime `'a` defined here
    |
diff --git a/src/test/ui/regions/regions-trait-object-subtyping.nll.stderr b/src/test/ui/regions/regions-trait-object-subtyping.nll.stderr
index bf325d56013..26f0fcae638 100644
--- a/src/test/ui/regions/regions-trait-object-subtyping.nll.stderr
+++ b/src/test/ui/regions/regions-trait-object-subtyping.nll.stderr
@@ -7,7 +7,7 @@ LL | fn foo3<'a,'b>(x: &'a mut dyn Dummy) -> &'b mut dyn Dummy {
    |         lifetime `'a` defined here
 LL |     // Without knowing 'a:'b, we can't coerce
 LL |     x
-   |     ^ returning this value requires that `'a` must outlive `'b`
+   |     ^ function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a`
    |
    = help: consider adding the following bound: `'a: 'b`
    = note: requirement occurs because of a mutable reference to dyn Dummy
@@ -23,7 +23,7 @@ LL | fn foo4<'a:'b,'b>(x: Wrapper<&'a mut dyn Dummy>) -> Wrapper<&'b mut dyn Dum
    |         lifetime `'a` defined here
 LL |     // We can't coerce because it is packed in `Wrapper`
 LL |     x
-   |     ^ returning this value requires that `'b` must outlive `'a`
+   |     ^ function was supposed to return data with lifetime `'a` but it is returning data with lifetime `'b`
    |
    = help: consider adding the following bound: `'b: 'a`
    = note: requirement occurs because of a mutable reference to dyn Dummy
diff --git a/src/test/ui/span/issue-39018.stderr b/src/test/ui/span/issue-39018.stderr
index 92e86bf5d6c..e2e7ce1ed18 100644
--- a/src/test/ui/span/issue-39018.stderr
+++ b/src/test/ui/span/issue-39018.stderr
@@ -7,10 +7,11 @@ LL |     let x = "Hello " + "World!";
    |             |        `+` cannot be used to concatenate two `&str` strings
    |             &str
    |
-help: `to_owned()` can be used to create an owned `String` from a string reference. String concatenation appends the string on the right to the string on the left and may require reallocation. This requires ownership of the string on the left
+   = note: string concatenation requires an owned `String` on the left
+help: create an owned `String` from a string reference
    |
 LL |     let x = "Hello ".to_owned() + "World!";
-   |             ~~~~~~~~~~~~~~~~~~~
+   |                     +++++++++++
 
 error[E0369]: cannot add `World` to `World`
   --> $DIR/issue-39018.rs:8:26
@@ -46,10 +47,10 @@ LL |     let x = "Hello " + "World!".to_owned();
    |             |        `+` cannot be used to concatenate a `&str` with a `String`
    |             &str
    |
-help: `to_owned()` can be used to create an owned `String` from a string reference. String concatenation appends the string on the right to the string on the left and may require reallocation. This requires ownership of the string on the left
+help: create an owned `String` on the left and add a borrow on the right
    |
 LL |     let x = "Hello ".to_owned() + &"World!".to_owned();
-   |             ~~~~~~~~~~~~~~~~~~~   ~~~~~~~~~~~~~~~~~~~~
+   |                     +++++++++++   +
 
 error[E0369]: cannot add `&String` to `&String`
   --> $DIR/issue-39018.rs:26:16
@@ -60,10 +61,12 @@ LL |     let _ = &a + &b;
    |             |  `+` cannot be used to concatenate two `&str` strings
    |             &String
    |
-help: String concatenation appends the string on the right to the string on the left and may require reallocation. This requires ownership of the string on the left
+   = note: string concatenation requires an owned `String` on the left
+help: remove the borrow to obtain an owned `String`
    |
-LL |     let _ = a + &b;
-   |             ~
+LL -     let _ = &a + &b;
+LL +     let _ = a + &b;
+   | 
 
 error[E0369]: cannot add `String` to `&String`
   --> $DIR/issue-39018.rs:27:16
@@ -74,10 +77,11 @@ LL |     let _ = &a + b;
    |             |  `+` cannot be used to concatenate a `&str` with a `String`
    |             &String
    |
-help: `to_owned()` can be used to create an owned `String` from a string reference. String concatenation appends the string on the right to the string on the left and may require reallocation. This requires ownership of the string on the left
+help: remove the borrow on the left and add one on the right
    |
-LL |     let _ = a + &b;
-   |             ~   ~~
+LL -     let _ = &a + b;
+LL +     let _ = a + &b;
+   | 
 
 error[E0308]: mismatched types
   --> $DIR/issue-39018.rs:29:17
@@ -97,10 +101,10 @@ LL |     let _ = e + b;
    |             | `+` cannot be used to concatenate a `&str` with a `String`
    |             &String
    |
-help: `to_owned()` can be used to create an owned `String` from a string reference. String concatenation appends the string on the right to the string on the left and may require reallocation. This requires ownership of the string on the left
+help: create an owned `String` on the left and add a borrow on the right
    |
 LL |     let _ = e.to_owned() + &b;
-   |             ~~~~~~~~~~~~   ~~
+   |              +++++++++++   +
 
 error[E0369]: cannot add `&String` to `&String`
   --> $DIR/issue-39018.rs:31:15
@@ -111,10 +115,11 @@ LL |     let _ = e + &b;
    |             | `+` cannot be used to concatenate two `&str` strings
    |             &String
    |
-help: `to_owned()` can be used to create an owned `String` from a string reference. String concatenation appends the string on the right to the string on the left and may require reallocation. This requires ownership of the string on the left
+   = note: string concatenation requires an owned `String` on the left
+help: create an owned `String` from a string reference
    |
 LL |     let _ = e.to_owned() + &b;
-   |             ~~~~~~~~~~~~
+   |              +++++++++++
 
 error[E0369]: cannot add `&str` to `&String`
   --> $DIR/issue-39018.rs:32:15
@@ -125,10 +130,11 @@ LL |     let _ = e + d;
    |             | `+` cannot be used to concatenate two `&str` strings
    |             &String
    |
-help: `to_owned()` can be used to create an owned `String` from a string reference. String concatenation appends the string on the right to the string on the left and may require reallocation. This requires ownership of the string on the left
+   = note: string concatenation requires an owned `String` on the left
+help: create an owned `String` from a string reference
    |
 LL |     let _ = e.to_owned() + d;
-   |             ~~~~~~~~~~~~
+   |              +++++++++++
 
 error[E0369]: cannot add `&&str` to `&String`
   --> $DIR/issue-39018.rs:33:15
@@ -139,10 +145,11 @@ LL |     let _ = e + &d;
    |             | `+` cannot be used to concatenate two `&str` strings
    |             &String
    |
-help: `to_owned()` can be used to create an owned `String` from a string reference. String concatenation appends the string on the right to the string on the left and may require reallocation. This requires ownership of the string on the left
+   = note: string concatenation requires an owned `String` on the left
+help: create an owned `String` from a string reference
    |
 LL |     let _ = e.to_owned() + &d;
-   |             ~~~~~~~~~~~~
+   |              +++++++++++
 
 error[E0369]: cannot add `&&str` to `&&str`
   --> $DIR/issue-39018.rs:34:16
@@ -169,10 +176,11 @@ LL |     let _ = c + &d;
    |             | `+` cannot be used to concatenate two `&str` strings
    |             &str
    |
-help: `to_owned()` can be used to create an owned `String` from a string reference. String concatenation appends the string on the right to the string on the left and may require reallocation. This requires ownership of the string on the left
+   = note: string concatenation requires an owned `String` on the left
+help: create an owned `String` from a string reference
    |
 LL |     let _ = c.to_owned() + &d;
-   |             ~~~~~~~~~~~~
+   |              +++++++++++
 
 error[E0369]: cannot add `&str` to `&str`
   --> $DIR/issue-39018.rs:37:15
@@ -183,10 +191,11 @@ LL |     let _ = c + d;
    |             | `+` cannot be used to concatenate two `&str` strings
    |             &str
    |
-help: `to_owned()` can be used to create an owned `String` from a string reference. String concatenation appends the string on the right to the string on the left and may require reallocation. This requires ownership of the string on the left
+   = note: string concatenation requires an owned `String` on the left
+help: create an owned `String` from a string reference
    |
 LL |     let _ = c.to_owned() + d;
-   |             ~~~~~~~~~~~~
+   |              +++++++++++
 
 error: aborting due to 14 previous errors
 
diff --git a/src/test/ui/str/str-concat-on-double-ref.stderr b/src/test/ui/str/str-concat-on-double-ref.stderr
index dee28897f4d..bd354679f78 100644
--- a/src/test/ui/str/str-concat-on-double-ref.stderr
+++ b/src/test/ui/str/str-concat-on-double-ref.stderr
@@ -7,10 +7,11 @@ LL |     let c = a + b;
    |             | `+` cannot be used to concatenate two `&str` strings
    |             &String
    |
-help: `to_owned()` can be used to create an owned `String` from a string reference. String concatenation appends the string on the right to the string on the left and may require reallocation. This requires ownership of the string on the left
+   = note: string concatenation requires an owned `String` on the left
+help: create an owned `String` from a string reference
    |
 LL |     let c = a.to_owned() + b;
-   |             ~~~~~~~~~~~~
+   |              +++++++++++
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/terminal-width/non-1-width-unicode-multiline-label.stderr b/src/test/ui/terminal-width/non-1-width-unicode-multiline-label.stderr
index 480f442fedd..bf277362dba 100644
--- a/src/test/ui/terminal-width/non-1-width-unicode-multiline-label.stderr
+++ b/src/test/ui/terminal-width/non-1-width-unicode-multiline-label.stderr
@@ -7,10 +7,11 @@ LL | ...ཽཾཿ྄ཱྀྀྂྃ྅྆྇ྈྉྊྋྌྍྎྏྐྑྒྒྷྔ
    |                                                  |              `+` cannot be used to concatenate two `&str` strings
    |                                                  &str
    |
-help: `to_owned()` can be used to create an owned `String` from a string reference. String concatenation appends the string on the right to the string on the left and may require reallocation. This requires ownership of the string on the left
+   = note: string concatenation requires an owned `String` on the left
+help: create an owned `String` from a string reference
    |
 LL |     let _ = "ༀ༁༂༃༄༅༆༇༈༉༊་༌།༎༏༐༑༒༓༔༕༖༗༘༙༚༛༜༝༞༟༠༡༢༣༤༥༦༧༨༩༪༫༬༭༮༯༰༱༲༳༴༵༶༷༸༹༺༻༼༽༾༿ཀཁགགྷངཅཆཇ཈ཉཊཋཌཌྷཎཏཐདདྷནཔཕབབྷམཙཚཛཛྷཝཞཟའཡརལཤཥསཧཨཀྵཪཫཬ཭཮཯཰ཱཱཱིིུུྲྀཷླྀཹེཻོཽཾཿ྄ཱྀྀྂྃ྅྆྇ྈྉྊྋྌྍྎྏྐྑྒྒྷྔྕྖྗ྘ྙྚྛྜྜྷྞྟྠྡྡྷྣྤྥྦྦྷྨྩྪྫྫྷྭྮྯྰྱྲླྴྵྶྷྸྐྵྺྻྼ྽྾྿࿀࿁࿂࿃࿄࿅࿆࿇࿈࿉࿊࿋࿌࿍࿎࿏࿐࿑࿒࿓࿔࿕࿖࿗࿘࿙࿚"; let _a = unicode_is_fun.to_owned() + " really fun!";
-   |                                                                                                                                                                           ~~~~~~~~~~~~~~~~~~~~~~~~~
+   |                                                                                                                                                                                         +++++++++++
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/tuple/array-diagnostics.rs b/src/test/ui/tuple/array-diagnostics.rs
new file mode 100644
index 00000000000..1929dab0731
--- /dev/null
+++ b/src/test/ui/tuple/array-diagnostics.rs
@@ -0,0 +1,7 @@
+fn main() {
+    let _tmp = [
+        ("C200B40A82", 3),
+        ("C200B40A83", 4) //~ ERROR: expected function, found `(&'static str, {integer})` [E0618]
+        ("C200B40A8537", 5),
+    ];
+}
diff --git a/src/test/ui/tuple/array-diagnostics.stderr b/src/test/ui/tuple/array-diagnostics.stderr
new file mode 100644
index 00000000000..a10d7af470c
--- /dev/null
+++ b/src/test/ui/tuple/array-diagnostics.stderr
@@ -0,0 +1,9 @@
+error[E0618]: expected function, found `(&'static str, {integer})`
+  --> $DIR/array-diagnostics.rs:4:9
+   |
+LL |         ("C200B40A83", 4)
+   |         ^^^^^^^^^^^^^^^^^- help: consider separating array elements with a comma: `,`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0618`.
diff --git a/src/test/ui/variance/variance-contravariant-arg-object.nll.stderr b/src/test/ui/variance/variance-contravariant-arg-object.nll.stderr
index 91d4fd2e971..3315eaaf1c0 100644
--- a/src/test/ui/variance/variance-contravariant-arg-object.nll.stderr
+++ b/src/test/ui/variance/variance-contravariant-arg-object.nll.stderr
@@ -7,7 +7,7 @@ LL | fn get_min_from_max<'min, 'max>(v: Box<dyn Get<&'max i32>>)
    |                     lifetime `'min` defined here
 ...
 LL |     v
-   |     ^ returning this value requires that `'min` must outlive `'max`
+   |     ^ function was supposed to return data with lifetime `'max` but it is returning data with lifetime `'min`
    |
    = help: consider adding the following bound: `'min: 'max`
 
@@ -20,7 +20,7 @@ LL | fn get_max_from_min<'min, 'max, G>(v: Box<dyn Get<&'min i32>>)
    |                     lifetime `'min` defined here
 ...
 LL |     v
-   |     ^ returning this value requires that `'min` must outlive `'max`
+   |     ^ function was supposed to return data with lifetime `'max` but it is returning data with lifetime `'min`
    |
    = help: consider adding the following bound: `'min: 'max`
 
diff --git a/src/test/ui/variance/variance-covariant-arg-object.nll.stderr b/src/test/ui/variance/variance-covariant-arg-object.nll.stderr
index 37fdea960be..b116b8e263f 100644
--- a/src/test/ui/variance/variance-covariant-arg-object.nll.stderr
+++ b/src/test/ui/variance/variance-covariant-arg-object.nll.stderr
@@ -7,7 +7,7 @@ LL | fn get_min_from_max<'min, 'max>(v: Box<dyn Get<&'max i32>>)
    |                     lifetime `'min` defined here
 ...
 LL |     v
-   |     ^ returning this value requires that `'min` must outlive `'max`
+   |     ^ function was supposed to return data with lifetime `'max` but it is returning data with lifetime `'min`
    |
    = help: consider adding the following bound: `'min: 'max`
 
@@ -20,7 +20,7 @@ LL | fn get_max_from_min<'min, 'max, G>(v: Box<dyn Get<&'min i32>>)
    |                     lifetime `'min` defined here
 ...
 LL |     v
-   |     ^ returning this value requires that `'min` must outlive `'max`
+   |     ^ function was supposed to return data with lifetime `'max` but it is returning data with lifetime `'min`
    |
    = help: consider adding the following bound: `'min: 'max`
 
diff --git a/src/test/ui/variance/variance-invariant-arg-object.nll.stderr b/src/test/ui/variance/variance-invariant-arg-object.nll.stderr
index f6265980af7..303c7f3388a 100644
--- a/src/test/ui/variance/variance-invariant-arg-object.nll.stderr
+++ b/src/test/ui/variance/variance-invariant-arg-object.nll.stderr
@@ -7,7 +7,7 @@ LL | fn get_min_from_max<'min, 'max>(v: Box<dyn Get<&'max i32>>)
    |                     lifetime `'min` defined here
 ...
 LL |     v
-   |     ^ returning this value requires that `'min` must outlive `'max`
+   |     ^ function was supposed to return data with lifetime `'max` but it is returning data with lifetime `'min`
    |
    = help: consider adding the following bound: `'min: 'max`
 
@@ -20,7 +20,7 @@ LL | fn get_max_from_min<'min, 'max, G>(v: Box<dyn Get<&'min i32>>)
    |                     lifetime `'min` defined here
 ...
 LL |     v
-   |     ^ returning this value requires that `'min` must outlive `'max`
+   |     ^ function was supposed to return data with lifetime `'max` but it is returning data with lifetime `'min`
    |
    = help: consider adding the following bound: `'min: 'max`
 
diff --git a/src/test/ui/variance/variance-use-contravariant-struct-1.nll.stderr b/src/test/ui/variance/variance-use-contravariant-struct-1.nll.stderr
index eddd4b217c0..837c70ca313 100644
--- a/src/test/ui/variance/variance-use-contravariant-struct-1.nll.stderr
+++ b/src/test/ui/variance/variance-use-contravariant-struct-1.nll.stderr
@@ -7,7 +7,7 @@ LL | fn foo<'min,'max>(v: SomeStruct<&'max ()>)
    |        lifetime `'min` defined here
 ...
 LL |     v
-   |     ^ returning this value requires that `'min` must outlive `'max`
+   |     ^ function was supposed to return data with lifetime `'max` but it is returning data with lifetime `'min`
    |
    = help: consider adding the following bound: `'min: 'max`
 
diff --git a/src/test/ui/variance/variance-use-covariant-struct-1.nll.stderr b/src/test/ui/variance/variance-use-covariant-struct-1.nll.stderr
index a86c1b93a73..bab858c5acb 100644
--- a/src/test/ui/variance/variance-use-covariant-struct-1.nll.stderr
+++ b/src/test/ui/variance/variance-use-covariant-struct-1.nll.stderr
@@ -7,7 +7,7 @@ LL | fn foo<'min,'max>(v: SomeStruct<&'min ()>)
    |        lifetime `'min` defined here
 ...
 LL |     v
-   |     ^ returning this value requires that `'min` must outlive `'max`
+   |     ^ function was supposed to return data with lifetime `'max` but it is returning data with lifetime `'min`
    |
    = help: consider adding the following bound: `'min: 'max`
 
diff --git a/src/test/ui/variance/variance-use-invariant-struct-1.nll.stderr b/src/test/ui/variance/variance-use-invariant-struct-1.nll.stderr
index 6890cb115c3..f1df2a88b6b 100644
--- a/src/test/ui/variance/variance-use-invariant-struct-1.nll.stderr
+++ b/src/test/ui/variance/variance-use-invariant-struct-1.nll.stderr
@@ -7,7 +7,7 @@ LL | fn foo<'min,'max>(v: SomeStruct<&'max ()>)
    |        lifetime `'min` defined here
 ...
 LL |     v
-   |     ^ returning this value requires that `'min` must outlive `'max`
+   |     ^ function was supposed to return data with lifetime `'max` but it is returning data with lifetime `'min`
    |
    = help: consider adding the following bound: `'min: 'max`
    = note: requirement occurs because of the type SomeStruct<&()>, which makes the generic argument &() invariant
@@ -23,7 +23,7 @@ LL | fn bar<'min,'max>(v: SomeStruct<&'min ()>)
    |        lifetime `'min` defined here
 ...
 LL |     v
-   |     ^ returning this value requires that `'min` must outlive `'max`
+   |     ^ function was supposed to return data with lifetime `'max` but it is returning data with lifetime `'min`
    |
    = help: consider adding the following bound: `'min: 'max`
    = note: requirement occurs because of the type SomeStruct<&()>, which makes the generic argument &() invariant
diff --git a/src/test/ui/wf/wf-static-method.nll.stderr b/src/test/ui/wf/wf-static-method.nll.stderr
index 9c066a7bdb0..26504311195 100644
--- a/src/test/ui/wf/wf-static-method.nll.stderr
+++ b/src/test/ui/wf/wf-static-method.nll.stderr
@@ -7,7 +7,7 @@ LL | impl<'a, 'b> Foo<'a, 'b, Evil<'a, 'b>> for () {
    |      lifetime `'a` defined here
 ...
 LL |         u
-   |         ^ returning this value requires that `'b` must outlive `'a`
+   |         ^ associated function was supposed to return data with lifetime `'a` but it is returning data with lifetime `'b`
    |
    = help: consider adding the following bound: `'b: 'a`
 
@@ -33,7 +33,7 @@ LL | impl<'a, 'b> Evil<'a, 'b> {
    |      lifetime `'a` defined here
 LL |     fn inherent_evil(u: &'b u32) -> &'a u32 {
 LL |         u
-   |         ^ returning this value requires that `'b` must outlive `'a`
+   |         ^ associated function was supposed to return data with lifetime `'a` but it is returning data with lifetime `'b`
    |
    = help: consider adding the following bound: `'b: 'a`
 
@@ -45,7 +45,7 @@ LL | fn evil<'a, 'b>(b: &'b u32) -> &'a u32 {
    |         |
    |         lifetime `'a` defined here
 LL |     <()>::static_evil(b)
-   |     ^^^^^^^^^^^^^^^^^^^^ returning this value requires that `'b` must outlive `'a`
+   |     ^^^^^^^^^^^^^^^^^^^^ function was supposed to return data with lifetime `'a` but it is returning data with lifetime `'b`
    |
    = help: consider adding the following bound: `'b: 'a`
 
@@ -57,7 +57,7 @@ LL | fn indirect_evil<'a, 'b>(b: &'b u32) -> &'a u32 {
    |                  |
    |                  lifetime `'a` defined here
 LL |     <IndirectEvil>::static_evil(b)
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ returning this value requires that `'b` must outlive `'a`
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ function was supposed to return data with lifetime `'a` but it is returning data with lifetime `'b`
    |
    = help: consider adding the following bound: `'b: 'a`
 
@@ -69,7 +69,7 @@ LL | fn inherent_evil<'a, 'b>(b: &'b u32) -> &'a u32 {
    |                  |
    |                  lifetime `'a` defined here
 LL |     <Evil>::inherent_evil(b)
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^ returning this value requires that `'b` must outlive `'a`
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^ function was supposed to return data with lifetime `'a` but it is returning data with lifetime `'b`
    |
    = help: consider adding the following bound: `'b: 'a`