Auto merge of #137248 - matthiaskrgr:rollup-s18zjau, r=matthiaskrgr

Rollup of 9 pull requests

Successful merges:

 - #136936 (Use 'yes' instead of 'while-echo' in tests/ui/process/process-sigpipe.rs except 'nto')
 - #137026 (Stabilize (and const-stabilize) `integer_sign_cast`)
 - #137059 (fix: Alloc new errorcode E0803 for E0495)
 - #137177 (Update `minifier-rs` version to `0.3.5`)
 - #137210 (compiler: Stop reexporting stuff in cg_llvm::abi)
 - #137213 (Remove `rustc_middle::mir::tcx` module.)
 - #137216 (eval_outlives: bail out early if both regions are in the same SCC)
 - #137228 (Fix typo in hidden internal docs of `TrustedRandomAccess`)
 - #137242 (Add reference annotations for the `do_not_recommend` attribute)

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

64 files changed, 585 insertions, 546 deletions

diff --git a/Cargo.lock b/Cargo.lock
index bb17717aceb..22a349b2d32 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2211,9 +2211,9 @@ dependencies = [
 
 [[package]]
 name = "minifier"
-version = "0.3.4"
+version = "0.3.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1cf47565b1430f5fe6c81d3afcb4b835271348d7eb35294a4d592e38dd09ea22"
+checksum = "9bfdc64e2f805f3d12965f10522000bae36e88d2cfea44112331f467d4f4bf68"
 
 [[package]]
 name = "minimal-lexical"
diff --git a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
index e778340cb65..b2cc58fbe11 100644
--- a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
@@ -18,12 +18,11 @@ use rustc_hir::intravisit::{Visitor, walk_block, walk_expr};
 use rustc_hir::{CoroutineDesugaring, CoroutineKind, CoroutineSource, LangItem, PatField};
 use rustc_middle::bug;
 use rustc_middle::hir::nested_filter::OnlyBodies;
-use rustc_middle::mir::tcx::PlaceTy;
 use rustc_middle::mir::{
     self, AggregateKind, BindingForm, BorrowKind, ClearCrossCrate, ConstraintCategory,
     FakeBorrowKind, FakeReadCause, LocalDecl, LocalInfo, LocalKind, Location, MutBorrowKind,
-    Operand, Place, PlaceRef, ProjectionElem, Rvalue, Statement, StatementKind, Terminator,
-    TerminatorKind, VarBindingForm, VarDebugInfoContents,
+    Operand, Place, PlaceRef, PlaceTy, ProjectionElem, Rvalue, Statement, StatementKind,
+    Terminator, TerminatorKind, VarBindingForm, VarDebugInfoContents,
 };
 use rustc_middle::ty::print::PrintTraitRefExt as _;
 use rustc_middle::ty::{
diff --git a/compiler/rustc_borrowck/src/diagnostics/mod.rs b/compiler/rustc_borrowck/src/diagnostics/mod.rs
index 07ea369c5c7..7da089c5e8c 100644
--- a/compiler/rustc_borrowck/src/diagnostics/mod.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/mod.rs
@@ -13,10 +13,9 @@ use rustc_infer::infer::{
 };
 use rustc_infer::traits::SelectionError;
 use rustc_middle::bug;
-use rustc_middle::mir::tcx::PlaceTy;
 use rustc_middle::mir::{
     AggregateKind, CallSource, ConstOperand, ConstraintCategory, FakeReadCause, Local, LocalInfo,
-    LocalKind, Location, Operand, Place, PlaceRef, ProjectionElem, Rvalue, Statement,
+    LocalKind, Location, Operand, Place, PlaceRef, PlaceTy, ProjectionElem, Rvalue, Statement,
     StatementKind, Terminator, TerminatorKind, find_self_call,
 };
 use rustc_middle::ty::print::Print;
diff --git a/compiler/rustc_borrowck/src/lib.rs b/compiler/rustc_borrowck/src/lib.rs
index 22ce0fd1ea7..a98984a4b4c 100644
--- a/compiler/rustc_borrowck/src/lib.rs
+++ b/compiler/rustc_borrowck/src/lib.rs
@@ -33,7 +33,6 @@ use rustc_index::{IndexSlice, IndexVec};
 use rustc_infer::infer::{
     InferCtxt, NllRegionVariableOrigin, RegionVariableOrigin, TyCtxtInferExt,
 };
-use rustc_middle::mir::tcx::PlaceTy;
 use rustc_middle::mir::*;
 use rustc_middle::query::Providers;
 use rustc_middle::ty::fold::fold_regions;
diff --git a/compiler/rustc_borrowck/src/region_infer/mod.rs b/compiler/rustc_borrowck/src/region_infer/mod.rs
index d2268c4779d..e0e3e028c61 100644
--- a/compiler/rustc_borrowck/src/region_infer/mod.rs
+++ b/compiler/rustc_borrowck/src/region_infer/mod.rs
@@ -1267,6 +1267,11 @@ impl<'tcx> RegionInferenceContext<'tcx> {
         let sub_region_scc = self.constraint_sccs.scc(sub_region);
         let sup_region_scc = self.constraint_sccs.scc(sup_region);
 
+        if sub_region_scc == sup_region_scc {
+            debug!("{sup_region:?}: {sub_region:?} holds trivially; they are in the same SCC");
+            return true;
+        }
+
         // If we are checking that `'sup: 'sub`, and `'sub` contains
         // some placeholder that `'sup` cannot name, then this is only
         // true if `'sup` outlives static.
diff --git a/compiler/rustc_borrowck/src/type_check/mod.rs b/compiler/rustc_borrowck/src/type_check/mod.rs
index 93081919ec7..84759a0ae04 100644
--- a/compiler/rustc_borrowck/src/type_check/mod.rs
+++ b/compiler/rustc_borrowck/src/type_check/mod.rs
@@ -19,7 +19,6 @@ use rustc_infer::infer::{
     BoundRegion, BoundRegionConversionTime, InferCtxt, NllRegionVariableOrigin,
 };
 use rustc_infer::traits::PredicateObligations;
-use rustc_middle::mir::tcx::PlaceTy;
 use rustc_middle::mir::visit::{NonMutatingUseContext, PlaceContext, Visitor};
 use rustc_middle::mir::*;
 use rustc_middle::traits::query::NoSolution;
diff --git a/compiler/rustc_codegen_llvm/src/abi.rs b/compiler/rustc_codegen_llvm/src/abi.rs
index 28f423efc21..8c75125e009 100644
--- a/compiler/rustc_codegen_llvm/src/abi.rs
+++ b/compiler/rustc_codegen_llvm/src/abi.rs
@@ -2,19 +2,18 @@ use std::borrow::Borrow;
 use std::cmp;
 
 use libc::c_uint;
-use rustc_abi as abi;
-pub(crate) use rustc_abi::ExternAbi;
-use rustc_abi::{HasDataLayout, Primitive, Reg, RegKind, Size};
+use rustc_abi::{BackendRepr, HasDataLayout, Primitive, Reg, RegKind, Size};
 use rustc_codegen_ssa::MemFlags;
 use rustc_codegen_ssa::mir::operand::{OperandRef, OperandValue};
 use rustc_codegen_ssa::mir::place::{PlaceRef, PlaceValue};
 use rustc_codegen_ssa::traits::*;
 use rustc_middle::ty::Ty;
 use rustc_middle::ty::layout::LayoutOf;
-pub(crate) use rustc_middle::ty::layout::{WIDE_PTR_ADDR, WIDE_PTR_EXTRA};
 use rustc_middle::{bug, ty};
 use rustc_session::config;
-pub(crate) use rustc_target::callconv::*;
+use rustc_target::callconv::{
+    ArgAbi, ArgAttribute, ArgAttributes, ArgExtension, CastTarget, Conv, FnAbi, PassMode,
+};
 use rustc_target::spec::SanitizerSet;
 use smallvec::SmallVec;
 
@@ -458,7 +457,7 @@ impl<'ll, 'tcx> FnAbiLlvmExt<'ll, 'tcx> for FnAbi<'tcx, Ty<'tcx>> {
         match &self.ret.mode {
             PassMode::Direct(attrs) => {
                 attrs.apply_attrs_to_llfn(llvm::AttributePlace::ReturnValue, cx, llfn);
-                if let abi::BackendRepr::Scalar(scalar) = self.ret.layout.backend_repr {
+                if let BackendRepr::Scalar(scalar) = self.ret.layout.backend_repr {
                     apply_range_attr(llvm::AttributePlace::ReturnValue, scalar);
                 }
             }
@@ -499,7 +498,7 @@ impl<'ll, 'tcx> FnAbiLlvmExt<'ll, 'tcx> for FnAbi<'tcx, Ty<'tcx>> {
                 }
                 PassMode::Direct(attrs) => {
                     let i = apply(attrs);
-                    if let abi::BackendRepr::Scalar(scalar) = arg.layout.backend_repr {
+                    if let BackendRepr::Scalar(scalar) = arg.layout.backend_repr {
                         apply_range_attr(llvm::AttributePlace::Argument(i), scalar);
                     }
                 }
@@ -514,9 +513,7 @@ impl<'ll, 'tcx> FnAbiLlvmExt<'ll, 'tcx> for FnAbi<'tcx, Ty<'tcx>> {
                 PassMode::Pair(a, b) => {
                     let i = apply(a);
                     let ii = apply(b);
-                    if let abi::BackendRepr::ScalarPair(scalar_a, scalar_b) =
-                        arg.layout.backend_repr
-                    {
+                    if let BackendRepr::ScalarPair(scalar_a, scalar_b) = arg.layout.backend_repr {
                         apply_range_attr(llvm::AttributePlace::Argument(i), scalar_a);
                         apply_range_attr(llvm::AttributePlace::Argument(ii), scalar_b);
                     }
@@ -576,7 +573,7 @@ impl<'ll, 'tcx> FnAbiLlvmExt<'ll, 'tcx> for FnAbi<'tcx, Ty<'tcx>> {
         }
         if bx.cx.sess().opts.optimize != config::OptLevel::No
                 && llvm_util::get_version() < (19, 0, 0)
-                && let abi::BackendRepr::Scalar(scalar) = self.ret.layout.backend_repr
+                && let BackendRepr::Scalar(scalar) = self.ret.layout.backend_repr
                 && matches!(scalar.primitive(), Primitive::Int(..))
                 // If the value is a boolean, the range is 0..2 and that ultimately
                 // become 0..0 when the type becomes i1, which would be rejected
diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs b/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
index 59c3fe635d0..98d59f5a8ae 100644
--- a/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
+++ b/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
@@ -11,7 +11,9 @@ use rustc_codegen_ssa::traits::*;
 use rustc_hir::def::{CtorKind, DefKind};
 use rustc_hir::def_id::{DefId, LOCAL_CRATE};
 use rustc_middle::bug;
-use rustc_middle::ty::layout::{HasTypingEnv, LayoutOf, TyAndLayout};
+use rustc_middle::ty::layout::{
+    HasTypingEnv, LayoutOf, TyAndLayout, WIDE_PTR_ADDR, WIDE_PTR_EXTRA,
+};
 use rustc_middle::ty::{
     self, AdtKind, CoroutineArgsExt, ExistentialTraitRef, Instance, Ty, TyCtxt, Visibility,
 };
@@ -34,12 +36,12 @@ use crate::common::{AsCCharPtr, CodegenCx};
 use crate::debuginfo::dwarf_const;
 use crate::debuginfo::metadata::type_map::build_type_with_children;
 use crate::debuginfo::utils::{WidePtrKind, wide_pointer_kind};
+use crate::llvm;
 use crate::llvm::debuginfo::{
     DIDescriptor, DIFile, DIFlags, DILexicalBlock, DIScope, DIType, DebugEmissionKind,
     DebugNameTableKind,
 };
 use crate::value::Value;
-use crate::{abi, llvm};
 
 impl PartialEq for llvm::Metadata {
     fn eq(&self, other: &Self) -> bool {
@@ -211,16 +213,16 @@ fn build_pointer_or_reference_di_node<'ll, 'tcx>(
                     };
 
                     let layout = cx.layout_of(layout_type);
-                    let addr_field = layout.field(cx, abi::WIDE_PTR_ADDR);
-                    let extra_field = layout.field(cx, abi::WIDE_PTR_EXTRA);
+                    let addr_field = layout.field(cx, WIDE_PTR_ADDR);
+                    let extra_field = layout.field(cx, WIDE_PTR_EXTRA);
 
                     let (addr_field_name, extra_field_name) = match wide_pointer_kind {
                         WidePtrKind::Dyn => ("pointer", "vtable"),
                         WidePtrKind::Slice => ("data_ptr", "length"),
                     };
 
-                    assert_eq!(abi::WIDE_PTR_ADDR, 0);
-                    assert_eq!(abi::WIDE_PTR_EXTRA, 1);
+                    assert_eq!(WIDE_PTR_ADDR, 0);
+                    assert_eq!(WIDE_PTR_EXTRA, 1);
 
                     // The data pointer type is a regular, thin pointer, regardless of whether this
                     // is a slice or a trait object.
@@ -242,7 +244,7 @@ fn build_pointer_or_reference_di_node<'ll, 'tcx>(
                             owner,
                             addr_field_name,
                             (addr_field.size, addr_field.align.abi),
-                            layout.fields.offset(abi::WIDE_PTR_ADDR),
+                            layout.fields.offset(WIDE_PTR_ADDR),
                             DIFlags::FlagZero,
                             data_ptr_type_di_node,
                             None,
@@ -252,7 +254,7 @@ fn build_pointer_or_reference_di_node<'ll, 'tcx>(
                             owner,
                             extra_field_name,
                             (extra_field.size, extra_field.align.abi),
-                            layout.fields.offset(abi::WIDE_PTR_EXTRA),
+                            layout.fields.offset(WIDE_PTR_EXTRA),
                             DIFlags::FlagZero,
                             type_di_node(cx, extra_field.ty),
                             None,
diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs b/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs
index 17f2d5f4e73..10819a53b1d 100644
--- a/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs
+++ b/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs
@@ -22,6 +22,7 @@ use rustc_session::config::{self, DebugInfo};
 use rustc_span::{
     BytePos, Pos, SourceFile, SourceFileAndLine, SourceFileHash, Span, StableSourceFileId, Symbol,
 };
+use rustc_target::callconv::FnAbi;
 use rustc_target::spec::DebuginfoKind;
 use smallvec::SmallVec;
 use tracing::debug;
@@ -29,7 +30,6 @@ use tracing::debug;
 use self::metadata::{UNKNOWN_COLUMN_NUMBER, UNKNOWN_LINE_NUMBER, file_metadata, type_di_node};
 use self::namespace::mangled_name_of_instance;
 use self::utils::{DIB, create_DIArray, is_node_local_to_unit};
-use crate::abi::FnAbi;
 use crate::builder::Builder;
 use crate::common::{AsCCharPtr, CodegenCx};
 use crate::llvm;
diff --git a/compiler/rustc_codegen_llvm/src/declare.rs b/compiler/rustc_codegen_llvm/src/declare.rs
index cebceef1b93..e79662ebc64 100644
--- a/compiler/rustc_codegen_llvm/src/declare.rs
+++ b/compiler/rustc_codegen_llvm/src/declare.rs
@@ -16,10 +16,11 @@ use rustc_codegen_ssa::traits::TypeMembershipCodegenMethods;
 use rustc_data_structures::fx::FxIndexSet;
 use rustc_middle::ty::{Instance, Ty};
 use rustc_sanitizers::{cfi, kcfi};
+use rustc_target::callconv::FnAbi;
 use smallvec::SmallVec;
 use tracing::debug;
 
-use crate::abi::{FnAbi, FnAbiLlvmExt};
+use crate::abi::FnAbiLlvmExt;
 use crate::common::AsCCharPtr;
 use crate::context::{CodegenCx, SimpleCx};
 use crate::llvm::AttributePlace::Function;
diff --git a/compiler/rustc_codegen_llvm/src/intrinsic.rs b/compiler/rustc_codegen_llvm/src/intrinsic.rs
index 8b976885904..7e1a9d361e6 100644
--- a/compiler/rustc_codegen_llvm/src/intrinsic.rs
+++ b/compiler/rustc_codegen_llvm/src/intrinsic.rs
@@ -1,7 +1,7 @@
 use std::assert_matches::assert_matches;
 use std::cmp::Ordering;
 
-use rustc_abi::{self as abi, Align, Float, HasDataLayout, Primitive, Size};
+use rustc_abi::{Align, BackendRepr, ExternAbi, Float, HasDataLayout, Primitive, Size};
 use rustc_codegen_ssa::base::{compare_simd_types, wants_msvc_seh, wants_wasm_eh};
 use rustc_codegen_ssa::common::{IntPredicate, TypeKind};
 use rustc_codegen_ssa::errors::{ExpectedPointerMutability, InvalidMonomorphization};
@@ -14,10 +14,11 @@ use rustc_middle::ty::layout::{FnAbiOf, HasTyCtxt, HasTypingEnv, LayoutOf};
 use rustc_middle::ty::{self, GenericArgsRef, Ty};
 use rustc_middle::{bug, span_bug};
 use rustc_span::{Span, Symbol, sym};
+use rustc_target::callconv::{FnAbi, PassMode};
 use rustc_target::spec::{HasTargetSpec, PanicStrategy};
 use tracing::debug;
 
-use crate::abi::{ExternAbi, FnAbi, FnAbiLlvmExt, LlvmType, PassMode};
+use crate::abi::{FnAbiLlvmExt, LlvmType};
 use crate::builder::Builder;
 use crate::context::CodegenCx;
 use crate::llvm::{self, Metadata};
@@ -257,7 +258,7 @@ impl<'ll, 'tcx> IntrinsicCallBuilderMethods<'tcx> for Builder<'_, 'll, 'tcx> {
             }
             sym::va_arg => {
                 match fn_abi.ret.layout.backend_repr {
-                    abi::BackendRepr::Scalar(scalar) => {
+                    BackendRepr::Scalar(scalar) => {
                         match scalar.primitive() {
                             Primitive::Int(..) => {
                                 if self.cx().size_of(ret_ty).bytes() < 4 {
@@ -470,7 +471,7 @@ impl<'ll, 'tcx> IntrinsicCallBuilderMethods<'tcx> for Builder<'_, 'll, 'tcx> {
             }
 
             sym::raw_eq => {
-                use abi::BackendRepr::*;
+                use BackendRepr::*;
                 let tp_ty = fn_args.type_at(0);
                 let layout = self.layout_of(tp_ty).layout;
                 let use_integer_compare = match layout.backend_repr() {
@@ -582,8 +583,7 @@ impl<'ll, 'tcx> IntrinsicCallBuilderMethods<'tcx> for Builder<'_, 'll, 'tcx> {
                 }
 
                 let llret_ty = if ret_ty.is_simd()
-                    && let abi::BackendRepr::Memory { .. } =
-                        self.layout_of(ret_ty).layout.backend_repr
+                    && let BackendRepr::Memory { .. } = self.layout_of(ret_ty).layout.backend_repr
                 {
                     let (size, elem_ty) = ret_ty.simd_size_and_type(self.tcx());
                     let elem_ll_ty = match elem_ty.kind() {
diff --git a/compiler/rustc_codegen_ssa/src/mir/place.rs b/compiler/rustc_codegen_ssa/src/mir/place.rs
index eb4270ffe80..e32d298869b 100644
--- a/compiler/rustc_codegen_ssa/src/mir/place.rs
+++ b/compiler/rustc_codegen_ssa/src/mir/place.rs
@@ -1,7 +1,7 @@
 use rustc_abi::Primitive::{Int, Pointer};
 use rustc_abi::{Align, BackendRepr, FieldsShape, Size, TagEncoding, VariantIdx, Variants};
+use rustc_middle::mir::PlaceTy;
 use rustc_middle::mir::interpret::Scalar;
-use rustc_middle::mir::tcx::PlaceTy;
 use rustc_middle::ty::layout::{HasTyCtxt, LayoutOf, TyAndLayout};
 use rustc_middle::ty::{self, Ty};
 use rustc_middle::{bug, mir};
diff --git a/compiler/rustc_error_codes/src/error_codes/E0803.md b/compiler/rustc_error_codes/src/error_codes/E0803.md
new file mode 100644
index 00000000000..4c022688a2d
--- /dev/null
+++ b/compiler/rustc_error_codes/src/error_codes/E0803.md
@@ -0,0 +1,46 @@
+A trait implementation returns a reference without an
+explicit lifetime linking it to `self`.
+It commonly arises in generic trait implementations
+requiring explicit lifetime bounds.
+
+Erroneous code example:
+
+```compile_fail,E0803
+trait DataAccess<T> {
+    fn get_ref(&self) -> T;
+}
+
+struct Container<'a> {
+    value: &'a f64,
+}
+
+// Attempting to implement reference return
+impl<'a> DataAccess<&f64> for Container<'a> {
+    fn get_ref(&self) -> &f64 { // Error: Lifetime mismatch
+        self.value
+    }
+}
+```
+
+The trait method returns &f64 requiring an independent lifetime
+The struct Container<'a> carries lifetime parameter 'a
+The compiler cannot verify if the returned reference satisfies 'a constraints
+Solution
+Explicitly bind lifetimes to clarify constraints:
+```
+// Modified trait with explicit lifetime binding
+trait DataAccess<'a, T> {
+    fn get_ref(&'a self) -> T;
+}
+
+struct Container<'a> {
+    value: &'a f64,
+}
+
+// Correct implementation (bound lifetimes)
+impl<'a> DataAccess<'a, &'a f64> for Container<'a> {
+    fn get_ref(&'a self) -> &'a f64 {
+        self.value
+    }
+}
+```
diff --git a/compiler/rustc_error_codes/src/lib.rs b/compiler/rustc_error_codes/src/lib.rs
index e970b16f610..098ca42be2b 100644
--- a/compiler/rustc_error_codes/src/lib.rs
+++ b/compiler/rustc_error_codes/src/lib.rs
@@ -546,6 +546,7 @@ E0799: 0799,
 E0800: 0800,
 E0801: 0801,
 E0802: 0802,
+E0803: 0803,
         );
     )
 }
diff --git a/compiler/rustc_middle/src/mir/mod.rs b/compiler/rustc_middle/src/mir/mod.rs
index 00e21700fb2..528da4ca057 100644
--- a/compiler/rustc_middle/src/mir/mod.rs
+++ b/compiler/rustc_middle/src/mir/mod.rs
@@ -53,7 +53,6 @@ pub mod pretty;
 mod query;
 mod statement;
 mod syntax;
-pub mod tcx;
 mod terminator;
 
 pub mod traversal;
diff --git a/compiler/rustc_middle/src/mir/statement.rs b/compiler/rustc_middle/src/mir/statement.rs
index 690a907f9a3..595a5e548b0 100644
--- a/compiler/rustc_middle/src/mir/statement.rs
+++ b/compiler/rustc_middle/src/mir/statement.rs
@@ -1,7 +1,10 @@
 //! Functionality for statements, operands, places, and things that appear in them.
 
+use tracing::{debug, instrument};
+
 use super::interpret::GlobalAlloc;
 use super::*;
+use crate::ty::CoroutineArgsExt;
 
 ///////////////////////////////////////////////////////////////////////////
 // Statements
@@ -40,6 +43,162 @@ impl<'tcx> StatementKind<'tcx> {
 ///////////////////////////////////////////////////////////////////////////
 // Places
 
+#[derive(Copy, Clone, Debug, TypeFoldable, TypeVisitable)]
+pub struct PlaceTy<'tcx> {
+    pub ty: Ty<'tcx>,
+    /// Downcast to a particular variant of an enum or a coroutine, if included.
+    pub variant_index: Option<VariantIdx>,
+}
+
+// At least on 64 bit systems, `PlaceTy` should not be larger than two or three pointers.
+#[cfg(target_pointer_width = "64")]
+rustc_data_structures::static_assert_size!(PlaceTy<'_>, 16);
+
+impl<'tcx> PlaceTy<'tcx> {
+    #[inline]
+    pub fn from_ty(ty: Ty<'tcx>) -> PlaceTy<'tcx> {
+        PlaceTy { ty, variant_index: None }
+    }
+
+    /// `place_ty.field_ty(tcx, f)` computes the type of a given field.
+    ///
+    /// Most clients of `PlaceTy` can instead just extract the relevant type
+    /// directly from their `PlaceElem`, but some instances of `ProjectionElem<V, T>`
+    /// do not carry a `Ty` for `T`.
+    ///
+    /// Note that the resulting type has not been normalized.
+    #[instrument(level = "debug", skip(tcx), ret)]
+    pub fn field_ty(self, tcx: TyCtxt<'tcx>, f: FieldIdx) -> Ty<'tcx> {
+        if let Some(variant_index) = self.variant_index {
+            match *self.ty.kind() {
+                ty::Adt(adt_def, args) if adt_def.is_enum() => {
+                    adt_def.variant(variant_index).fields[f].ty(tcx, args)
+                }
+                ty::Coroutine(def_id, args) => {
+                    let mut variants = args.as_coroutine().state_tys(def_id, tcx);
+                    let Some(mut variant) = variants.nth(variant_index.into()) else {
+                        bug!("variant {variant_index:?} of coroutine out of range: {self:?}");
+                    };
+
+                    variant
+                        .nth(f.index())
+                        .unwrap_or_else(|| bug!("field {f:?} out of range: {self:?}"))
+                }
+                _ => bug!("can't downcast non-adt non-coroutine type: {self:?}"),
+            }
+        } else {
+            match self.ty.kind() {
+                ty::Adt(adt_def, args) if !adt_def.is_enum() => {
+                    adt_def.non_enum_variant().fields[f].ty(tcx, args)
+                }
+                ty::Closure(_, args) => args
+                    .as_closure()
+                    .upvar_tys()
+                    .get(f.index())
+                    .copied()
+                    .unwrap_or_else(|| bug!("field {f:?} out of range: {self:?}")),
+                ty::CoroutineClosure(_, args) => args
+                    .as_coroutine_closure()
+                    .upvar_tys()
+                    .get(f.index())
+                    .copied()
+                    .unwrap_or_else(|| bug!("field {f:?} out of range: {self:?}")),
+                // Only prefix fields (upvars and current state) are
+                // accessible without a variant index.
+                ty::Coroutine(_, args) => args
+                    .as_coroutine()
+                    .prefix_tys()
+                    .get(f.index())
+                    .copied()
+                    .unwrap_or_else(|| bug!("field {f:?} out of range: {self:?}")),
+                ty::Tuple(tys) => tys
+                    .get(f.index())
+                    .copied()
+                    .unwrap_or_else(|| bug!("field {f:?} out of range: {self:?}")),
+                _ => bug!("can't project out of {self:?}"),
+            }
+        }
+    }
+
+    pub fn multi_projection_ty(
+        self,
+        tcx: TyCtxt<'tcx>,
+        elems: &[PlaceElem<'tcx>],
+    ) -> PlaceTy<'tcx> {
+        elems.iter().fold(self, |place_ty, &elem| place_ty.projection_ty(tcx, elem))
+    }
+
+    /// Convenience wrapper around `projection_ty_core` for
+    /// `PlaceElem`, where we can just use the `Ty` that is already
+    /// stored inline on field projection elems.
+    pub fn projection_ty(self, tcx: TyCtxt<'tcx>, elem: PlaceElem<'tcx>) -> PlaceTy<'tcx> {
+        self.projection_ty_core(tcx, &elem, |_, _, ty| ty, |_, ty| ty)
+    }
+
+    /// `place_ty.projection_ty_core(tcx, elem, |...| { ... })`
+    /// projects `place_ty` onto `elem`, returning the appropriate
+    /// `Ty` or downcast variant corresponding to that projection.
+    /// The `handle_field` callback must map a `FieldIdx` to its `Ty`,
+    /// (which should be trivial when `T` = `Ty`).
+    pub fn projection_ty_core<V, T>(
+        self,
+        tcx: TyCtxt<'tcx>,
+        elem: &ProjectionElem<V, T>,
+        mut handle_field: impl FnMut(&Self, FieldIdx, T) -> Ty<'tcx>,
+        mut handle_opaque_cast_and_subtype: impl FnMut(&Self, T) -> Ty<'tcx>,
+    ) -> PlaceTy<'tcx>
+    where
+        V: ::std::fmt::Debug,
+        T: ::std::fmt::Debug + Copy,
+    {
+        if self.variant_index.is_some() && !matches!(elem, ProjectionElem::Field(..)) {
+            bug!("cannot use non field projection on downcasted place")
+        }
+        let answer = match *elem {
+            ProjectionElem::Deref => {
+                let ty = self.ty.builtin_deref(true).unwrap_or_else(|| {
+                    bug!("deref projection of non-dereferenceable ty {:?}", self)
+                });
+                PlaceTy::from_ty(ty)
+            }
+            ProjectionElem::Index(_) | ProjectionElem::ConstantIndex { .. } => {
+                PlaceTy::from_ty(self.ty.builtin_index().unwrap())
+            }
+            ProjectionElem::Subslice { from, to, from_end } => {
+                PlaceTy::from_ty(match self.ty.kind() {
+                    ty::Slice(..) => self.ty,
+                    ty::Array(inner, _) if !from_end => Ty::new_array(tcx, *inner, to - from),
+                    ty::Array(inner, size) if from_end => {
+                        let size = size
+                            .try_to_target_usize(tcx)
+                            .expect("expected subslice projection on fixed-size array");
+                        let len = size - from - to;
+                        Ty::new_array(tcx, *inner, len)
+                    }
+                    _ => bug!("cannot subslice non-array type: `{:?}`", self),
+                })
+            }
+            ProjectionElem::Downcast(_name, index) => {
+                PlaceTy { ty: self.ty, variant_index: Some(index) }
+            }
+            ProjectionElem::Field(f, fty) => PlaceTy::from_ty(handle_field(&self, f, fty)),
+            ProjectionElem::OpaqueCast(ty) => {
+                PlaceTy::from_ty(handle_opaque_cast_and_subtype(&self, ty))
+            }
+            ProjectionElem::Subtype(ty) => {
+                PlaceTy::from_ty(handle_opaque_cast_and_subtype(&self, ty))
+            }
+
+            // FIXME(unsafe_binders): Rename `handle_opaque_cast_and_subtype` to be more general.
+            ProjectionElem::UnwrapUnsafeBinder(ty) => {
+                PlaceTy::from_ty(handle_opaque_cast_and_subtype(&self, ty))
+            }
+        };
+        debug!("projection_ty self: {:?} elem: {:?} yields: {:?}", self, elem, answer);
+        answer
+    }
+}
+
 impl<V, T> ProjectionElem<V, T> {
     /// Returns `true` if the target of this projection may refer to a different region of memory
     /// than the base.
@@ -183,6 +342,25 @@ impl<'tcx> Place<'tcx> {
 
         self.as_ref().project_deeper(more_projections, tcx)
     }
+
+    pub fn ty_from<D: ?Sized>(
+        local: Local,
+        projection: &[PlaceElem<'tcx>],
+        local_decls: &D,
+        tcx: TyCtxt<'tcx>,
+    ) -> PlaceTy<'tcx>
+    where
+        D: HasLocalDecls<'tcx>,
+    {
+        PlaceTy::from_ty(local_decls.local_decls()[local].ty).multi_projection_ty(tcx, projection)
+    }
+
+    pub fn ty<D: ?Sized>(&self, local_decls: &D, tcx: TyCtxt<'tcx>) -> PlaceTy<'tcx>
+    where
+        D: HasLocalDecls<'tcx>,
+    {
+        Place::ty_from(self.local, self.projection, local_decls, tcx)
+    }
 }
 
 impl From<Local> for Place<'_> {
@@ -285,6 +463,13 @@ impl<'tcx> PlaceRef<'tcx> {
 
         Place { local: self.local, projection: tcx.mk_place_elems(new_projections) }
     }
+
+    pub fn ty<D: ?Sized>(&self, local_decls: &D, tcx: TyCtxt<'tcx>) -> PlaceTy<'tcx>
+    where
+        D: HasLocalDecls<'tcx>,
+    {
+        Place::ty_from(self.local, self.projection, local_decls, tcx)
+    }
 }
 
 impl From<Local> for PlaceRef<'_> {
@@ -379,6 +564,28 @@ impl<'tcx> Operand<'tcx> {
         let const_ty = self.constant()?.const_.ty();
         if let ty::FnDef(def_id, args) = *const_ty.kind() { Some((def_id, args)) } else { None }
     }
+
+    pub fn ty<D: ?Sized>(&self, local_decls: &D, tcx: TyCtxt<'tcx>) -> Ty<'tcx>
+    where
+        D: HasLocalDecls<'tcx>,
+    {
+        match self {
+            &Operand::Copy(ref l) | &Operand::Move(ref l) => l.ty(local_decls, tcx).ty,
+            Operand::Constant(c) => c.const_.ty(),
+        }
+    }
+
+    pub fn span<D: ?Sized>(&self, local_decls: &D) -> Span
+    where
+        D: HasLocalDecls<'tcx>,
+    {
+        match self {
+            &Operand::Copy(ref l) | &Operand::Move(ref l) => {
+                local_decls.local_decls()[l.local].source_info.span
+            }
+            Operand::Constant(c) => c.span,
+        }
+    }
 }
 
 impl<'tcx> ConstOperand<'tcx> {
@@ -404,6 +611,11 @@ impl<'tcx> ConstOperand<'tcx> {
 ///////////////////////////////////////////////////////////////////////////
 /// Rvalues
 
+pub enum RvalueInitializationState {
+    Shallow,
+    Deep,
+}
+
 impl<'tcx> Rvalue<'tcx> {
     /// Returns true if rvalue can be safely removed when the result is unused.
     #[inline]
@@ -443,6 +655,70 @@ impl<'tcx> Rvalue<'tcx> {
             | Rvalue::WrapUnsafeBinder(_, _) => true,
         }
     }
+
+    pub fn ty<D: ?Sized>(&self, local_decls: &D, tcx: TyCtxt<'tcx>) -> Ty<'tcx>
+    where
+        D: HasLocalDecls<'tcx>,
+    {
+        match *self {
+            Rvalue::Use(ref operand) => operand.ty(local_decls, tcx),
+            Rvalue::Repeat(ref operand, count) => {
+                Ty::new_array_with_const_len(tcx, operand.ty(local_decls, tcx), count)
+            }
+            Rvalue::ThreadLocalRef(did) => tcx.thread_local_ptr_ty(did),
+            Rvalue::Ref(reg, bk, ref place) => {
+                let place_ty = place.ty(local_decls, tcx).ty;
+                Ty::new_ref(tcx, reg, place_ty, bk.to_mutbl_lossy())
+            }
+            Rvalue::RawPtr(kind, ref place) => {
+                let place_ty = place.ty(local_decls, tcx).ty;
+                Ty::new_ptr(tcx, place_ty, kind.to_mutbl_lossy())
+            }
+            Rvalue::Len(..) => tcx.types.usize,
+            Rvalue::Cast(.., ty) => ty,
+            Rvalue::BinaryOp(op, box (ref lhs, ref rhs)) => {
+                let lhs_ty = lhs.ty(local_decls, tcx);
+                let rhs_ty = rhs.ty(local_decls, tcx);
+                op.ty(tcx, lhs_ty, rhs_ty)
+            }
+            Rvalue::UnaryOp(op, ref operand) => {
+                let arg_ty = operand.ty(local_decls, tcx);
+                op.ty(tcx, arg_ty)
+            }
+            Rvalue::Discriminant(ref place) => place.ty(local_decls, tcx).ty.discriminant_ty(tcx),
+            Rvalue::NullaryOp(NullOp::SizeOf | NullOp::AlignOf | NullOp::OffsetOf(..), _) => {
+                tcx.types.usize
+            }
+            Rvalue::NullaryOp(NullOp::ContractChecks, _)
+            | Rvalue::NullaryOp(NullOp::UbChecks, _) => tcx.types.bool,
+            Rvalue::Aggregate(ref ak, ref ops) => match **ak {
+                AggregateKind::Array(ty) => Ty::new_array(tcx, ty, ops.len() as u64),
+                AggregateKind::Tuple => {
+                    Ty::new_tup_from_iter(tcx, ops.iter().map(|op| op.ty(local_decls, tcx)))
+                }
+                AggregateKind::Adt(did, _, args, _, _) => tcx.type_of(did).instantiate(tcx, args),
+                AggregateKind::Closure(did, args) => Ty::new_closure(tcx, did, args),
+                AggregateKind::Coroutine(did, args) => Ty::new_coroutine(tcx, did, args),
+                AggregateKind::CoroutineClosure(did, args) => {
+                    Ty::new_coroutine_closure(tcx, did, args)
+                }
+                AggregateKind::RawPtr(ty, mutability) => Ty::new_ptr(tcx, ty, mutability),
+            },
+            Rvalue::ShallowInitBox(_, ty) => Ty::new_box(tcx, ty),
+            Rvalue::CopyForDeref(ref place) => place.ty(local_decls, tcx).ty,
+            Rvalue::WrapUnsafeBinder(_, ty) => ty,
+        }
+    }
+
+    #[inline]
+    /// Returns `true` if this rvalue is deeply initialized (most rvalues) or
+    /// whether its only shallowly initialized (`Rvalue::Box`).
+    pub fn initialization_state(&self) -> RvalueInitializationState {
+        match *self {
+            Rvalue::ShallowInitBox(_, _) => RvalueInitializationState::Shallow,
+            _ => RvalueInitializationState::Deep,
+        }
+    }
 }
 
 impl BorrowKind {
@@ -465,4 +741,124 @@ impl BorrowKind {
             BorrowKind::Mut { kind: MutBorrowKind::TwoPhaseBorrow } => true,
         }
     }
+
+    pub fn to_mutbl_lossy(self) -> hir::Mutability {
+        match self {
+            BorrowKind::Mut { .. } => hir::Mutability::Mut,
+            BorrowKind::Shared => hir::Mutability::Not,
+
+            // We have no type corresponding to a shallow borrow, so use
+            // `&` as an approximation.
+            BorrowKind::Fake(_) => hir::Mutability::Not,
+        }
+    }
+}
+
+impl<'tcx> UnOp {
+    pub fn ty(&self, tcx: TyCtxt<'tcx>, arg_ty: Ty<'tcx>) -> Ty<'tcx> {
+        match self {
+            UnOp::Not | UnOp::Neg => arg_ty,
+            UnOp::PtrMetadata => arg_ty.pointee_metadata_ty_or_projection(tcx),
+        }
+    }
+}
+
+impl<'tcx> BinOp {
+    pub fn ty(&self, tcx: TyCtxt<'tcx>, lhs_ty: Ty<'tcx>, rhs_ty: Ty<'tcx>) -> Ty<'tcx> {
+        // FIXME: handle SIMD correctly
+        match self {
+            &BinOp::Add
+            | &BinOp::AddUnchecked
+            | &BinOp::Sub
+            | &BinOp::SubUnchecked
+            | &BinOp::Mul
+            | &BinOp::MulUnchecked
+            | &BinOp::Div
+            | &BinOp::Rem
+            | &BinOp::BitXor
+            | &BinOp::BitAnd
+            | &BinOp::BitOr => {
+                // these should be integers or floats of the same size.
+                assert_eq!(lhs_ty, rhs_ty);
+                lhs_ty
+            }
+            &BinOp::AddWithOverflow | &BinOp::SubWithOverflow | &BinOp::MulWithOverflow => {
+                // these should be integers of the same size.
+                assert_eq!(lhs_ty, rhs_ty);
+                Ty::new_tup(tcx, &[lhs_ty, tcx.types.bool])
+            }
+            &BinOp::Shl
+            | &BinOp::ShlUnchecked
+            | &BinOp::Shr
+            | &BinOp::ShrUnchecked
+            | &BinOp::Offset => {
+                lhs_ty // lhs_ty can be != rhs_ty
+            }
+            &BinOp::Eq | &BinOp::Lt | &BinOp::Le | &BinOp::Ne | &BinOp::Ge | &BinOp::Gt => {
+                tcx.types.bool
+            }
+            &BinOp::Cmp => {
+                // these should be integer-like types of the same size.
+                assert_eq!(lhs_ty, rhs_ty);
+                tcx.ty_ordering_enum(None)
+            }
+        }
+    }
+    pub(crate) fn to_hir_binop(self) -> hir::BinOpKind {
+        match self {
+            // HIR `+`/`-`/`*` can map to either of these MIR BinOp, depending
+            // on whether overflow checks are enabled or not.
+            BinOp::Add | BinOp::AddWithOverflow => hir::BinOpKind::Add,
+            BinOp::Sub | BinOp::SubWithOverflow => hir::BinOpKind::Sub,
+            BinOp::Mul | BinOp::MulWithOverflow => hir::BinOpKind::Mul,
+            BinOp::Div => hir::BinOpKind::Div,
+            BinOp::Rem => hir::BinOpKind::Rem,
+            BinOp::BitXor => hir::BinOpKind::BitXor,
+            BinOp::BitAnd => hir::BinOpKind::BitAnd,
+            BinOp::BitOr => hir::BinOpKind::BitOr,
+            BinOp::Shl => hir::BinOpKind::Shl,
+            BinOp::Shr => hir::BinOpKind::Shr,
+            BinOp::Eq => hir::BinOpKind::Eq,
+            BinOp::Ne => hir::BinOpKind::Ne,
+            BinOp::Lt => hir::BinOpKind::Lt,
+            BinOp::Gt => hir::BinOpKind::Gt,
+            BinOp::Le => hir::BinOpKind::Le,
+            BinOp::Ge => hir::BinOpKind::Ge,
+            // We don't have HIR syntax for these.
+            BinOp::Cmp
+            | BinOp::AddUnchecked
+            | BinOp::SubUnchecked
+            | BinOp::MulUnchecked
+            | BinOp::ShlUnchecked
+            | BinOp::ShrUnchecked
+            | BinOp::Offset => {
+                unreachable!()
+            }
+        }
+    }
+
+    /// If this is a `FooWithOverflow`, return `Some(Foo)`.
+    pub fn overflowing_to_wrapping(self) -> Option<BinOp> {
+        Some(match self {
+            BinOp::AddWithOverflow => BinOp::Add,
+            BinOp::SubWithOverflow => BinOp::Sub,
+            BinOp::MulWithOverflow => BinOp::Mul,
+            _ => return None,
+        })
+    }
+
+    /// Returns whether this is a `FooWithOverflow`
+    pub fn is_overflowing(self) -> bool {
+        self.overflowing_to_wrapping().is_some()
+    }
+
+    /// If this is a `Foo`, return `Some(FooWithOverflow)`.
+    pub fn wrapping_to_overflowing(self) -> Option<BinOp> {
+        Some(match self {
+            BinOp::Add => BinOp::AddWithOverflow,
+            BinOp::Sub => BinOp::SubWithOverflow,
+            BinOp::Mul => BinOp::MulWithOverflow,
+            _ => return None,
+        })
+    }
 }
diff --git a/compiler/rustc_middle/src/mir/syntax.rs b/compiler/rustc_middle/src/mir/syntax.rs
index dfd40a9535b..389792a04f8 100644
--- a/compiler/rustc_middle/src/mir/syntax.rs
+++ b/compiler/rustc_middle/src/mir/syntax.rs
@@ -1133,7 +1133,7 @@ pub type AssertMessage<'tcx> = AssertKind<Operand<'tcx>>;
 ///
 ///  1. The address in memory that the place refers to.
 ///  2. The provenance with which the place is being accessed.
-///  3. The type of the place and an optional variant index. See [`PlaceTy`][super::tcx::PlaceTy].
+///  3. The type of the place and an optional variant index. See [`PlaceTy`][super::PlaceTy].
 ///  4. Optionally, some metadata. This exists if and only if the type of the place is not `Sized`.
 ///
 /// We'll give a description below of how all pieces of the place except for the provenance are
diff --git a/compiler/rustc_middle/src/mir/tcx.rs b/compiler/rustc_middle/src/mir/tcx.rs
deleted file mode 100644
index 862f78d7259..00000000000
--- a/compiler/rustc_middle/src/mir/tcx.rs
+++ /dev/null
@@ -1,416 +0,0 @@
-/*!
- * Methods for the various MIR types. These are intended for use after
- * building is complete.
- */
-
-use rustc_hir as hir;
-use tracing::{debug, instrument};
-use ty::CoroutineArgsExt;
-
-use crate::mir::*;
-
-#[derive(Copy, Clone, Debug, TypeFoldable, TypeVisitable)]
-pub struct PlaceTy<'tcx> {
-    pub ty: Ty<'tcx>,
-    /// Downcast to a particular variant of an enum or a coroutine, if included.
-    pub variant_index: Option<VariantIdx>,
-}
-
-// At least on 64 bit systems, `PlaceTy` should not be larger than two or three pointers.
-#[cfg(target_pointer_width = "64")]
-rustc_data_structures::static_assert_size!(PlaceTy<'_>, 16);
-
-impl<'tcx> PlaceTy<'tcx> {
-    #[inline]
-    pub fn from_ty(ty: Ty<'tcx>) -> PlaceTy<'tcx> {
-        PlaceTy { ty, variant_index: None }
-    }
-
-    /// `place_ty.field_ty(tcx, f)` computes the type of a given field.
-    ///
-    /// Most clients of `PlaceTy` can instead just extract the relevant type
-    /// directly from their `PlaceElem`, but some instances of `ProjectionElem<V, T>`
-    /// do not carry a `Ty` for `T`.
-    ///
-    /// Note that the resulting type has not been normalized.
-    #[instrument(level = "debug", skip(tcx), ret)]
-    pub fn field_ty(self, tcx: TyCtxt<'tcx>, f: FieldIdx) -> Ty<'tcx> {
-        if let Some(variant_index) = self.variant_index {
-            match *self.ty.kind() {
-                ty::Adt(adt_def, args) if adt_def.is_enum() => {
-                    adt_def.variant(variant_index).fields[f].ty(tcx, args)
-                }
-                ty::Coroutine(def_id, args) => {
-                    let mut variants = args.as_coroutine().state_tys(def_id, tcx);
-                    let Some(mut variant) = variants.nth(variant_index.into()) else {
-                        bug!("variant {variant_index:?} of coroutine out of range: {self:?}");
-                    };
-
-                    variant
-                        .nth(f.index())
-                        .unwrap_or_else(|| bug!("field {f:?} out of range: {self:?}"))
-                }
-                _ => bug!("can't downcast non-adt non-coroutine type: {self:?}"),
-            }
-        } else {
-            match self.ty.kind() {
-                ty::Adt(adt_def, args) if !adt_def.is_enum() => {
-                    adt_def.non_enum_variant().fields[f].ty(tcx, args)
-                }
-                ty::Closure(_, args) => args
-                    .as_closure()
-                    .upvar_tys()
-                    .get(f.index())
-                    .copied()
-                    .unwrap_or_else(|| bug!("field {f:?} out of range: {self:?}")),
-                ty::CoroutineClosure(_, args) => args
-                    .as_coroutine_closure()
-                    .upvar_tys()
-                    .get(f.index())
-                    .copied()
-                    .unwrap_or_else(|| bug!("field {f:?} out of range: {self:?}")),
-                // Only prefix fields (upvars and current state) are
-                // accessible without a variant index.
-                ty::Coroutine(_, args) => args
-                    .as_coroutine()
-                    .prefix_tys()
-                    .get(f.index())
-                    .copied()
-                    .unwrap_or_else(|| bug!("field {f:?} out of range: {self:?}")),
-                ty::Tuple(tys) => tys
-                    .get(f.index())
-                    .copied()
-                    .unwrap_or_else(|| bug!("field {f:?} out of range: {self:?}")),
-                _ => bug!("can't project out of {self:?}"),
-            }
-        }
-    }
-
-    pub fn multi_projection_ty(
-        self,
-        tcx: TyCtxt<'tcx>,
-        elems: &[PlaceElem<'tcx>],
-    ) -> PlaceTy<'tcx> {
-        elems.iter().fold(self, |place_ty, &elem| place_ty.projection_ty(tcx, elem))
-    }
-
-    /// Convenience wrapper around `projection_ty_core` for
-    /// `PlaceElem`, where we can just use the `Ty` that is already
-    /// stored inline on field projection elems.
-    pub fn projection_ty(self, tcx: TyCtxt<'tcx>, elem: PlaceElem<'tcx>) -> PlaceTy<'tcx> {
-        self.projection_ty_core(tcx, &elem, |_, _, ty| ty, |_, ty| ty)
-    }
-
-    /// `place_ty.projection_ty_core(tcx, elem, |...| { ... })`
-    /// projects `place_ty` onto `elem`, returning the appropriate
-    /// `Ty` or downcast variant corresponding to that projection.
-    /// The `handle_field` callback must map a `FieldIdx` to its `Ty`,
-    /// (which should be trivial when `T` = `Ty`).
-    pub fn projection_ty_core<V, T>(
-        self,
-        tcx: TyCtxt<'tcx>,
-        elem: &ProjectionElem<V, T>,
-        mut handle_field: impl FnMut(&Self, FieldIdx, T) -> Ty<'tcx>,
-        mut handle_opaque_cast_and_subtype: impl FnMut(&Self, T) -> Ty<'tcx>,
-    ) -> PlaceTy<'tcx>
-    where
-        V: ::std::fmt::Debug,
-        T: ::std::fmt::Debug + Copy,
-    {
-        if self.variant_index.is_some() && !matches!(elem, ProjectionElem::Field(..)) {
-            bug!("cannot use non field projection on downcasted place")
-        }
-        let answer = match *elem {
-            ProjectionElem::Deref => {
-                let ty = self.ty.builtin_deref(true).unwrap_or_else(|| {
-                    bug!("deref projection of non-dereferenceable ty {:?}", self)
-                });
-                PlaceTy::from_ty(ty)
-            }
-            ProjectionElem::Index(_) | ProjectionElem::ConstantIndex { .. } => {
-                PlaceTy::from_ty(self.ty.builtin_index().unwrap())
-            }
-            ProjectionElem::Subslice { from, to, from_end } => {
-                PlaceTy::from_ty(match self.ty.kind() {
-                    ty::Slice(..) => self.ty,
-                    ty::Array(inner, _) if !from_end => Ty::new_array(tcx, *inner, to - from),
-                    ty::Array(inner, size) if from_end => {
-                        let size = size
-                            .try_to_target_usize(tcx)
-                            .expect("expected subslice projection on fixed-size array");
-                        let len = size - from - to;
-                        Ty::new_array(tcx, *inner, len)
-                    }
-                    _ => bug!("cannot subslice non-array type: `{:?}`", self),
-                })
-            }
-            ProjectionElem::Downcast(_name, index) => {
-                PlaceTy { ty: self.ty, variant_index: Some(index) }
-            }
-            ProjectionElem::Field(f, fty) => PlaceTy::from_ty(handle_field(&self, f, fty)),
-            ProjectionElem::OpaqueCast(ty) => {
-                PlaceTy::from_ty(handle_opaque_cast_and_subtype(&self, ty))
-            }
-            ProjectionElem::Subtype(ty) => {
-                PlaceTy::from_ty(handle_opaque_cast_and_subtype(&self, ty))
-            }
-
-            // FIXME(unsafe_binders): Rename `handle_opaque_cast_and_subtype` to be more general.
-            ProjectionElem::UnwrapUnsafeBinder(ty) => {
-                PlaceTy::from_ty(handle_opaque_cast_and_subtype(&self, ty))
-            }
-        };
-        debug!("projection_ty self: {:?} elem: {:?} yields: {:?}", self, elem, answer);
-        answer
-    }
-}
-
-impl<'tcx> Place<'tcx> {
-    pub fn ty_from<D: ?Sized>(
-        local: Local,
-        projection: &[PlaceElem<'tcx>],
-        local_decls: &D,
-        tcx: TyCtxt<'tcx>,
-    ) -> PlaceTy<'tcx>
-    where
-        D: HasLocalDecls<'tcx>,
-    {
-        PlaceTy::from_ty(local_decls.local_decls()[local].ty).multi_projection_ty(tcx, projection)
-    }
-
-    pub fn ty<D: ?Sized>(&self, local_decls: &D, tcx: TyCtxt<'tcx>) -> PlaceTy<'tcx>
-    where
-        D: HasLocalDecls<'tcx>,
-    {
-        Place::ty_from(self.local, self.projection, local_decls, tcx)
-    }
-}
-
-impl<'tcx> PlaceRef<'tcx> {
-    pub fn ty<D: ?Sized>(&self, local_decls: &D, tcx: TyCtxt<'tcx>) -> PlaceTy<'tcx>
-    where
-        D: HasLocalDecls<'tcx>,
-    {
-        Place::ty_from(self.local, self.projection, local_decls, tcx)
-    }
-}
-
-pub enum RvalueInitializationState {
-    Shallow,
-    Deep,
-}
-
-impl<'tcx> Rvalue<'tcx> {
-    pub fn ty<D: ?Sized>(&self, local_decls: &D, tcx: TyCtxt<'tcx>) -> Ty<'tcx>
-    where
-        D: HasLocalDecls<'tcx>,
-    {
-        match *self {
-            Rvalue::Use(ref operand) => operand.ty(local_decls, tcx),
-            Rvalue::Repeat(ref operand, count) => {
-                Ty::new_array_with_const_len(tcx, operand.ty(local_decls, tcx), count)
-            }
-            Rvalue::ThreadLocalRef(did) => tcx.thread_local_ptr_ty(did),
-            Rvalue::Ref(reg, bk, ref place) => {
-                let place_ty = place.ty(local_decls, tcx).ty;
-                Ty::new_ref(tcx, reg, place_ty, bk.to_mutbl_lossy())
-            }
-            Rvalue::RawPtr(kind, ref place) => {
-                let place_ty = place.ty(local_decls, tcx).ty;
-                Ty::new_ptr(tcx, place_ty, kind.to_mutbl_lossy())
-            }
-            Rvalue::Len(..) => tcx.types.usize,
-            Rvalue::Cast(.., ty) => ty,
-            Rvalue::BinaryOp(op, box (ref lhs, ref rhs)) => {
-                let lhs_ty = lhs.ty(local_decls, tcx);
-                let rhs_ty = rhs.ty(local_decls, tcx);
-                op.ty(tcx, lhs_ty, rhs_ty)
-            }
-            Rvalue::UnaryOp(op, ref operand) => {
-                let arg_ty = operand.ty(local_decls, tcx);
-                op.ty(tcx, arg_ty)
-            }
-            Rvalue::Discriminant(ref place) => place.ty(local_decls, tcx).ty.discriminant_ty(tcx),
-            Rvalue::NullaryOp(NullOp::SizeOf | NullOp::AlignOf | NullOp::OffsetOf(..), _) => {
-                tcx.types.usize
-            }
-            Rvalue::NullaryOp(NullOp::ContractChecks, _)
-            | Rvalue::NullaryOp(NullOp::UbChecks, _) => tcx.types.bool,
-            Rvalue::Aggregate(ref ak, ref ops) => match **ak {
-                AggregateKind::Array(ty) => Ty::new_array(tcx, ty, ops.len() as u64),
-                AggregateKind::Tuple => {
-                    Ty::new_tup_from_iter(tcx, ops.iter().map(|op| op.ty(local_decls, tcx)))
-                }
-                AggregateKind::Adt(did, _, args, _, _) => tcx.type_of(did).instantiate(tcx, args),
-                AggregateKind::Closure(did, args) => Ty::new_closure(tcx, did, args),
-                AggregateKind::Coroutine(did, args) => Ty::new_coroutine(tcx, did, args),
-                AggregateKind::CoroutineClosure(did, args) => {
-                    Ty::new_coroutine_closure(tcx, did, args)
-                }
-                AggregateKind::RawPtr(ty, mutability) => Ty::new_ptr(tcx, ty, mutability),
-            },
-            Rvalue::ShallowInitBox(_, ty) => Ty::new_box(tcx, ty),
-            Rvalue::CopyForDeref(ref place) => place.ty(local_decls, tcx).ty,
-            Rvalue::WrapUnsafeBinder(_, ty) => ty,
-        }
-    }
-
-    #[inline]
-    /// Returns `true` if this rvalue is deeply initialized (most rvalues) or
-    /// whether its only shallowly initialized (`Rvalue::Box`).
-    pub fn initialization_state(&self) -> RvalueInitializationState {
-        match *self {
-            Rvalue::ShallowInitBox(_, _) => RvalueInitializationState::Shallow,
-            _ => RvalueInitializationState::Deep,
-        }
-    }
-}
-
-impl<'tcx> Operand<'tcx> {
-    pub fn ty<D: ?Sized>(&self, local_decls: &D, tcx: TyCtxt<'tcx>) -> Ty<'tcx>
-    where
-        D: HasLocalDecls<'tcx>,
-    {
-        match self {
-            &Operand::Copy(ref l) | &Operand::Move(ref l) => l.ty(local_decls, tcx).ty,
-            Operand::Constant(c) => c.const_.ty(),
-        }
-    }
-
-    pub fn span<D: ?Sized>(&self, local_decls: &D) -> Span
-    where
-        D: HasLocalDecls<'tcx>,
-    {
-        match self {
-            &Operand::Copy(ref l) | &Operand::Move(ref l) => {
-                local_decls.local_decls()[l.local].source_info.span
-            }
-            Operand::Constant(c) => c.span,
-        }
-    }
-}
-
-impl<'tcx> BinOp {
-    pub fn ty(&self, tcx: TyCtxt<'tcx>, lhs_ty: Ty<'tcx>, rhs_ty: Ty<'tcx>) -> Ty<'tcx> {
-        // FIXME: handle SIMD correctly
-        match self {
-            &BinOp::Add
-            | &BinOp::AddUnchecked
-            | &BinOp::Sub
-            | &BinOp::SubUnchecked
-            | &BinOp::Mul
-            | &BinOp::MulUnchecked
-            | &BinOp::Div
-            | &BinOp::Rem
-            | &BinOp::BitXor
-            | &BinOp::BitAnd
-            | &BinOp::BitOr => {
-                // these should be integers or floats of the same size.
-                assert_eq!(lhs_ty, rhs_ty);
-                lhs_ty
-            }
-            &BinOp::AddWithOverflow | &BinOp::SubWithOverflow | &BinOp::MulWithOverflow => {
-                // these should be integers of the same size.
-                assert_eq!(lhs_ty, rhs_ty);
-                Ty::new_tup(tcx, &[lhs_ty, tcx.types.bool])
-            }
-            &BinOp::Shl
-            | &BinOp::ShlUnchecked
-            | &BinOp::Shr
-            | &BinOp::ShrUnchecked
-            | &BinOp::Offset => {
-                lhs_ty // lhs_ty can be != rhs_ty
-            }
-            &BinOp::Eq | &BinOp::Lt | &BinOp::Le | &BinOp::Ne | &BinOp::Ge | &BinOp::Gt => {
-                tcx.types.bool
-            }
-            &BinOp::Cmp => {
-                // these should be integer-like types of the same size.
-                assert_eq!(lhs_ty, rhs_ty);
-                tcx.ty_ordering_enum(None)
-            }
-        }
-    }
-}
-
-impl<'tcx> UnOp {
-    pub fn ty(&self, tcx: TyCtxt<'tcx>, arg_ty: Ty<'tcx>) -> Ty<'tcx> {
-        match self {
-            UnOp::Not | UnOp::Neg => arg_ty,
-            UnOp::PtrMetadata => arg_ty.pointee_metadata_ty_or_projection(tcx),
-        }
-    }
-}
-
-impl BorrowKind {
-    pub fn to_mutbl_lossy(self) -> hir::Mutability {
-        match self {
-            BorrowKind::Mut { .. } => hir::Mutability::Mut,
-            BorrowKind::Shared => hir::Mutability::Not,
-
-            // We have no type corresponding to a shallow borrow, so use
-            // `&` as an approximation.
-            BorrowKind::Fake(_) => hir::Mutability::Not,
-        }
-    }
-}
-
-impl BinOp {
-    pub(crate) fn to_hir_binop(self) -> hir::BinOpKind {
-        match self {
-            // HIR `+`/`-`/`*` can map to either of these MIR BinOp, depending
-            // on whether overflow checks are enabled or not.
-            BinOp::Add | BinOp::AddWithOverflow => hir::BinOpKind::Add,
-            BinOp::Sub | BinOp::SubWithOverflow => hir::BinOpKind::Sub,
-            BinOp::Mul | BinOp::MulWithOverflow => hir::BinOpKind::Mul,
-            BinOp::Div => hir::BinOpKind::Div,
-            BinOp::Rem => hir::BinOpKind::Rem,
-            BinOp::BitXor => hir::BinOpKind::BitXor,
-            BinOp::BitAnd => hir::BinOpKind::BitAnd,
-            BinOp::BitOr => hir::BinOpKind::BitOr,
-            BinOp::Shl => hir::BinOpKind::Shl,
-            BinOp::Shr => hir::BinOpKind::Shr,
-            BinOp::Eq => hir::BinOpKind::Eq,
-            BinOp::Ne => hir::BinOpKind::Ne,
-            BinOp::Lt => hir::BinOpKind::Lt,
-            BinOp::Gt => hir::BinOpKind::Gt,
-            BinOp::Le => hir::BinOpKind::Le,
-            BinOp::Ge => hir::BinOpKind::Ge,
-            // We don't have HIR syntax for these.
-            BinOp::Cmp
-            | BinOp::AddUnchecked
-            | BinOp::SubUnchecked
-            | BinOp::MulUnchecked
-            | BinOp::ShlUnchecked
-            | BinOp::ShrUnchecked
-            | BinOp::Offset => {
-                unreachable!()
-            }
-        }
-    }
-
-    /// If this is a `FooWithOverflow`, return `Some(Foo)`.
-    pub fn overflowing_to_wrapping(self) -> Option<BinOp> {
-        Some(match self {
-            BinOp::AddWithOverflow => BinOp::Add,
-            BinOp::SubWithOverflow => BinOp::Sub,
-            BinOp::MulWithOverflow => BinOp::Mul,
-            _ => return None,
-        })
-    }
-
-    /// Returns whether this is a `FooWithOverflow`
-    pub fn is_overflowing(self) -> bool {
-        self.overflowing_to_wrapping().is_some()
-    }
-
-    /// If this is a `Foo`, return `Some(FooWithOverflow)`.
-    pub fn wrapping_to_overflowing(self) -> Option<BinOp> {
-        Some(match self {
-            BinOp::Add => BinOp::AddWithOverflow,
-            BinOp::Sub => BinOp::SubWithOverflow,
-            BinOp::Mul => BinOp::MulWithOverflow,
-            _ => return None,
-        })
-    }
-}
diff --git a/compiler/rustc_mir_build/src/builder/custom/parse/instruction.rs b/compiler/rustc_mir_build/src/builder/custom/parse/instruction.rs
index eab414e150f..19669021eef 100644
--- a/compiler/rustc_mir_build/src/builder/custom/parse/instruction.rs
+++ b/compiler/rustc_mir_build/src/builder/custom/parse/instruction.rs
@@ -1,6 +1,5 @@
 use rustc_abi::{FieldIdx, VariantIdx};
 use rustc_middle::mir::interpret::Scalar;
-use rustc_middle::mir::tcx::PlaceTy;
 use rustc_middle::mir::*;
 use rustc_middle::thir::*;
 use rustc_middle::ty;
diff --git a/compiler/rustc_mir_dataflow/src/move_paths/builder.rs b/compiler/rustc_mir_dataflow/src/move_paths/builder.rs
index b6c259aa4e0..8bbc89fdcec 100644
--- a/compiler/rustc_mir_dataflow/src/move_paths/builder.rs
+++ b/compiler/rustc_mir_dataflow/src/move_paths/builder.rs
@@ -1,7 +1,6 @@
 use std::mem;
 
 use rustc_index::IndexVec;
-use rustc_middle::mir::tcx::{PlaceTy, RvalueInitializationState};
 use rustc_middle::mir::*;
 use rustc_middle::ty::{self, Ty, TyCtxt, TypeVisitableExt};
 use rustc_middle::{bug, span_bug};
diff --git a/compiler/rustc_mir_dataflow/src/value_analysis.rs b/compiler/rustc_mir_dataflow/src/value_analysis.rs
index a51af8c40fd..104a2e8c091 100644
--- a/compiler/rustc_mir_dataflow/src/value_analysis.rs
+++ b/compiler/rustc_mir_dataflow/src/value_analysis.rs
@@ -7,7 +7,6 @@ use rustc_data_structures::fx::{FxHashMap, FxIndexSet, StdEntry};
 use rustc_data_structures::stack::ensure_sufficient_stack;
 use rustc_index::IndexVec;
 use rustc_index::bit_set::DenseBitSet;
-use rustc_middle::mir::tcx::PlaceTy;
 use rustc_middle::mir::visit::{MutatingUseContext, PlaceContext, Visitor};
 use rustc_middle::mir::*;
 use rustc_middle::ty::{self, Ty, TyCtxt};
diff --git a/compiler/rustc_mir_transform/src/elaborate_drop.rs b/compiler/rustc_mir_transform/src/elaborate_drop.rs
index 2de55e38052..9330a9481f5 100644
--- a/compiler/rustc_mir_transform/src/elaborate_drop.rs
+++ b/compiler/rustc_mir_transform/src/elaborate_drop.rs
@@ -185,7 +185,7 @@ where
             place.ty(self.elaborator.body(), self.tcx()).ty
         } else {
             // We don't have a slice with all the locals, since some are in the patch.
-            tcx::PlaceTy::from_ty(self.elaborator.patch_ref().local_ty(place.local))
+            PlaceTy::from_ty(self.elaborator.patch_ref().local_ty(place.local))
                 .multi_projection_ty(self.elaborator.tcx(), place.projection)
                 .ty
         }
diff --git a/compiler/rustc_trait_selection/src/error_reporting/infer/region.rs b/compiler/rustc_trait_selection/src/error_reporting/infer/region.rs
index d009687ef14..fecb38ab597 100644
--- a/compiler/rustc_trait_selection/src/error_reporting/infer/region.rs
+++ b/compiler/rustc_trait_selection/src/error_reporting/infer/region.rs
@@ -2,7 +2,7 @@ use std::iter;
 
 use rustc_data_structures::fx::FxIndexSet;
 use rustc_errors::{
-    Applicability, Diag, E0309, E0310, E0311, E0495, Subdiagnostic, struct_span_code_err,
+    Applicability, Diag, E0309, E0310, E0311, E0803, Subdiagnostic, struct_span_code_err,
 };
 use rustc_hir::def::DefKind;
 use rustc_hir::def_id::{DefId, LocalDefId};
@@ -1032,7 +1032,7 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
         struct_span_code_err!(
             self.dcx(),
             var_origin.span(),
-            E0495,
+            E0803,
             "cannot infer an appropriate lifetime{} due to conflicting requirements",
             var_description
         )
diff --git a/library/core/src/iter/adapters/zip.rs b/library/core/src/iter/adapters/zip.rs
index 0c388115908..8090c98e7ed 100644
--- a/library/core/src/iter/adapters/zip.rs
+++ b/library/core/src/iter/adapters/zip.rs
@@ -556,13 +556,13 @@ impl<A: Debug + TrustedRandomAccessNoCoerce, B: Debug + TrustedRandomAccessNoCoe
 ///     * `std::iter::ExactSizeIterator::len`
 ///     * `std::iter::Iterator::__iterator_get_unchecked`
 ///     * `std::iter::TrustedRandomAccessNoCoerce::size`
-/// 5. If `T` is a subtype of `Self`, then `self` is allowed to be coerced
+/// 5. If `Self` is a subtype of `T`, then `self` is allowed to be coerced
 ///    to `T`. If `self` is coerced to `T` after `self.__iterator_get_unchecked(idx)` has already
 ///    been called, then no methods except for the ones listed under 4. are allowed to be called
 ///    on the resulting value of type `T`, either. Multiple such coercion steps are allowed.
 ///    Regarding 2. and 3., the number of times `__iterator_get_unchecked(idx)` or `next_back()` is
 ///    called on `self` and the resulting value of type `T` (and on further coercion results with
-///    sub-subtypes) are added together and their sums must not exceed the specified bounds.
+///    super-supertypes) are added together and their sums must not exceed the specified bounds.
 ///
 /// Further, given that these conditions are met, it must guarantee that:
 ///
@@ -570,7 +570,7 @@ impl<A: Debug + TrustedRandomAccessNoCoerce, B: Debug + TrustedRandomAccessNoCoe
 /// * It must be safe to call the methods listed above on `self` after calling
 ///   `self.__iterator_get_unchecked(idx)`, assuming that the required traits are implemented.
 /// * It must also be safe to drop `self` after calling `self.__iterator_get_unchecked(idx)`.
-/// * If `T` is a subtype of `Self`, then it must be safe to coerce `self` to `T`.
+/// * If `Self` is a subtype of `T`, then it must be safe to coerce `self` to `T`.
 //
 // FIXME: Clarify interaction with SourceIter/InPlaceIterable. Calling `SourceIter::as_inner`
 // after `__iterator_get_unchecked` is supposed to be allowed.
@@ -580,7 +580,7 @@ impl<A: Debug + TrustedRandomAccessNoCoerce, B: Debug + TrustedRandomAccessNoCoe
 pub unsafe trait TrustedRandomAccess: TrustedRandomAccessNoCoerce {}
 
 /// Like [`TrustedRandomAccess`] but without any of the requirements / guarantees around
-/// coercions to subtypes after `__iterator_get_unchecked` (they aren’t allowed here!), and
+/// coercions to supertypes after `__iterator_get_unchecked` (they aren’t allowed here!), and
 /// without the requirement that subtypes / supertypes implement `TrustedRandomAccessNoCoerce`.
 ///
 /// This trait was created in PR #85874 to fix soundness issue #85873 without performance regressions.
diff --git a/library/core/src/num/int_macros.rs b/library/core/src/num/int_macros.rs
index 96a290ad5a0..296b5ebdfaf 100644
--- a/library/core/src/num/int_macros.rs
+++ b/library/core/src/num/int_macros.rs
@@ -193,13 +193,13 @@ macro_rules! int_impl {
         /// Basic usage:
         ///
         /// ```
-        /// #![feature(integer_sign_cast)]
         ///
         #[doc = concat!("let n = -1", stringify!($SelfT), ";")]
         ///
         #[doc = concat!("assert_eq!(n.cast_unsigned(), ", stringify!($UnsignedT), "::MAX);")]
         /// ```
-        #[unstable(feature = "integer_sign_cast", issue = "125882")]
+        #[stable(feature = "integer_sign_cast", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "integer_sign_cast", since = "CURRENT_RUSTC_VERSION")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
diff --git a/library/core/src/num/nonzero.rs b/library/core/src/num/nonzero.rs
index 21bad6705ab..b59451d7c75 100644
--- a/library/core/src/num/nonzero.rs
+++ b/library/core/src/num/nonzero.rs
@@ -1633,14 +1633,14 @@ macro_rules! nonzero_integer_signedness_dependent_methods {
         /// Basic usage:
         ///
         /// ```
-        /// #![feature(integer_sign_cast)]
         /// # use std::num::NonZero;
         ///
         #[doc = concat!("let n = NonZero::<", stringify!($Int), ">::MAX;")]
         ///
         #[doc = concat!("assert_eq!(n.cast_signed(), NonZero::new(-1", stringify!($Sint), ").unwrap());")]
         /// ```
-        #[unstable(feature = "integer_sign_cast", issue = "125882")]
+        #[stable(feature = "integer_sign_cast", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "integer_sign_cast", since = "CURRENT_RUSTC_VERSION")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
@@ -2072,14 +2072,14 @@ macro_rules! nonzero_integer_signedness_dependent_methods {
         /// Basic usage:
         ///
         /// ```
-        /// #![feature(integer_sign_cast)]
         /// # use std::num::NonZero;
         ///
         #[doc = concat!("let n = NonZero::new(-1", stringify!($Int), ").unwrap();")]
         ///
         #[doc = concat!("assert_eq!(n.cast_unsigned(), NonZero::<", stringify!($Uint), ">::MAX);")]
         /// ```
-        #[unstable(feature = "integer_sign_cast", issue = "125882")]
+        #[stable(feature = "integer_sign_cast", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "integer_sign_cast", since = "CURRENT_RUSTC_VERSION")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
diff --git a/library/core/src/num/uint_macros.rs b/library/core/src/num/uint_macros.rs
index 29f6791ee6a..74d3ae699f6 100644
--- a/library/core/src/num/uint_macros.rs
+++ b/library/core/src/num/uint_macros.rs
@@ -223,13 +223,12 @@ macro_rules! uint_impl {
         /// Basic usage:
         ///
         /// ```
-        /// #![feature(integer_sign_cast)]
-        ///
         #[doc = concat!("let n = ", stringify!($SelfT), "::MAX;")]
         ///
         #[doc = concat!("assert_eq!(n.cast_signed(), -1", stringify!($SignedT), ");")]
         /// ```
-        #[unstable(feature = "integer_sign_cast", issue = "125882")]
+        #[stable(feature = "integer_sign_cast", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "integer_sign_cast", since = "CURRENT_RUSTC_VERSION")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
diff --git a/src/librustdoc/Cargo.toml b/src/librustdoc/Cargo.toml
index c593cdcbcd2..c07cc4dc347 100644
--- a/src/librustdoc/Cargo.toml
+++ b/src/librustdoc/Cargo.toml
@@ -13,7 +13,7 @@ rinja = { version = "0.3", default-features = false, features = ["config"] }
 base64 = "0.21.7"
 itertools = "0.12"
 indexmap = "2"
-minifier = { version = "0.3.4", default-features = false }
+minifier = { version = "0.3.5", default-features = false }
 pulldown-cmark-old = { version = "0.9.6", package = "pulldown-cmark", default-features = false }
 regex = "1"
 rustdoc-json-types = { path = "../rustdoc-json-types" }
diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/as_expression.current.stderr b/tests/ui/diagnostic_namespace/do_not_recommend/as_expression.current.stderr
index 28e7975c7a2..305fbbd275f 100644
--- a/tests/ui/diagnostic_namespace/do_not_recommend/as_expression.current.stderr
+++ b/tests/ui/diagnostic_namespace/do_not_recommend/as_expression.current.stderr
@@ -1,5 +1,5 @@
 error[E0277]: the trait bound `&str: AsExpression<Integer>` is not satisfied
-  --> $DIR/as_expression.rs:55:15
+  --> $DIR/as_expression.rs:56:15
    |
 LL |     SelectInt.check("bar");
    |               ^^^^^ the trait `AsExpression<Integer>` is not implemented for `&str`
diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/as_expression.next.stderr b/tests/ui/diagnostic_namespace/do_not_recommend/as_expression.next.stderr
index 4f685c508c7..90bb715a052 100644
--- a/tests/ui/diagnostic_namespace/do_not_recommend/as_expression.next.stderr
+++ b/tests/ui/diagnostic_namespace/do_not_recommend/as_expression.next.stderr
@@ -1,5 +1,5 @@
 error[E0277]: the trait bound `&str: AsExpression<<SelectInt as Expression>::SqlType>` is not satisfied
-  --> $DIR/as_expression.rs:55:21
+  --> $DIR/as_expression.rs:56:21
    |
 LL |     SelectInt.check("bar");
    |               ----- ^^^^^ the trait `AsExpression<<SelectInt as Expression>::SqlType>` is not implemented for `&str`
@@ -8,7 +8,7 @@ LL |     SelectInt.check("bar");
    |
    = help: the trait `AsExpression<Text>` is implemented for `&str`
 note: required by a bound in `Foo::check`
-  --> $DIR/as_expression.rs:46:12
+  --> $DIR/as_expression.rs:47:12
    |
 LL |     fn check<T>(&self, _: T) -> <T as AsExpression<<Self as Expression>::SqlType>>::Expression
    |        ----- required by a bound in this associated function
@@ -17,7 +17,7 @@ LL |         T: AsExpression<Self::SqlType>,
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `Foo::check`
 
 error[E0271]: type mismatch resolving `<SelectInt as Expression>::SqlType == Text`
-  --> $DIR/as_expression.rs:55:5
+  --> $DIR/as_expression.rs:56:5
    |
 LL |     SelectInt.check("bar");
    |     ^^^^^^^^^^^^^^^^^^^^^^ expected `Text`, found `Integer`
diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/as_expression.rs b/tests/ui/diagnostic_namespace/do_not_recommend/as_expression.rs
index 48c1ed2b02d..73a238ddf50 100644
--- a/tests/ui/diagnostic_namespace/do_not_recommend/as_expression.rs
+++ b/tests/ui/diagnostic_namespace/do_not_recommend/as_expression.rs
@@ -1,6 +1,7 @@
 //@ revisions: current next
 //@ ignore-compare-mode-next-solver (explicit revisions)
 //@[next] compile-flags: -Znext-solver
+//@ reference: attributes.diagnostic.do_not_recommend.intro
 
 pub trait Expression {
     type SqlType;
diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/does_not_acccept_args.current.stderr b/tests/ui/diagnostic_namespace/do_not_recommend/does_not_acccept_args.current.stderr
index 47597a5d405..8a478a5c733 100644
--- a/tests/ui/diagnostic_namespace/do_not_recommend/does_not_acccept_args.current.stderr
+++ b/tests/ui/diagnostic_namespace/do_not_recommend/does_not_acccept_args.current.stderr
@@ -1,5 +1,5 @@
 warning: `#[diagnostic::do_not_recommend]` does not expect any arguments
-  --> $DIR/does_not_acccept_args.rs:10:1
+  --> $DIR/does_not_acccept_args.rs:11:1
    |
 LL | #[diagnostic::do_not_recommend(not_accepted)]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -7,13 +7,13 @@ LL | #[diagnostic::do_not_recommend(not_accepted)]
    = note: `#[warn(unknown_or_malformed_diagnostic_attributes)]` on by default
 
 warning: `#[diagnostic::do_not_recommend]` does not expect any arguments
-  --> $DIR/does_not_acccept_args.rs:14:1
+  --> $DIR/does_not_acccept_args.rs:15:1
    |
 LL | #[diagnostic::do_not_recommend(not_accepted = "foo")]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 warning: `#[diagnostic::do_not_recommend]` does not expect any arguments
-  --> $DIR/does_not_acccept_args.rs:18:1
+  --> $DIR/does_not_acccept_args.rs:19:1
    |
 LL | #[diagnostic::do_not_recommend(not_accepted(42))]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/does_not_acccept_args.next.stderr b/tests/ui/diagnostic_namespace/do_not_recommend/does_not_acccept_args.next.stderr
index 47597a5d405..8a478a5c733 100644
--- a/tests/ui/diagnostic_namespace/do_not_recommend/does_not_acccept_args.next.stderr
+++ b/tests/ui/diagnostic_namespace/do_not_recommend/does_not_acccept_args.next.stderr
@@ -1,5 +1,5 @@
 warning: `#[diagnostic::do_not_recommend]` does not expect any arguments
-  --> $DIR/does_not_acccept_args.rs:10:1
+  --> $DIR/does_not_acccept_args.rs:11:1
    |
 LL | #[diagnostic::do_not_recommend(not_accepted)]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -7,13 +7,13 @@ LL | #[diagnostic::do_not_recommend(not_accepted)]
    = note: `#[warn(unknown_or_malformed_diagnostic_attributes)]` on by default
 
 warning: `#[diagnostic::do_not_recommend]` does not expect any arguments
-  --> $DIR/does_not_acccept_args.rs:14:1
+  --> $DIR/does_not_acccept_args.rs:15:1
    |
 LL | #[diagnostic::do_not_recommend(not_accepted = "foo")]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 warning: `#[diagnostic::do_not_recommend]` does not expect any arguments
-  --> $DIR/does_not_acccept_args.rs:18:1
+  --> $DIR/does_not_acccept_args.rs:19:1
    |
 LL | #[diagnostic::do_not_recommend(not_accepted(42))]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/does_not_acccept_args.rs b/tests/ui/diagnostic_namespace/do_not_recommend/does_not_acccept_args.rs
index eeff5e2e6e8..5c21c045e10 100644
--- a/tests/ui/diagnostic_namespace/do_not_recommend/does_not_acccept_args.rs
+++ b/tests/ui/diagnostic_namespace/do_not_recommend/does_not_acccept_args.rs
@@ -2,6 +2,7 @@
 //@ revisions: current next
 //@ ignore-compare-mode-next-solver (explicit revisions)
 //@[next] compile-flags: -Znext-solver
+//@ reference: attributes.diagnostic.do_not_recommend.syntax
 
 trait Foo {}
 trait Bar {}
diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/incorrect-locations.current.stderr b/tests/ui/diagnostic_namespace/do_not_recommend/incorrect-locations.current.stderr
index ee6ebabadd9..e348f0c8902 100644
--- a/tests/ui/diagnostic_namespace/do_not_recommend/incorrect-locations.current.stderr
+++ b/tests/ui/diagnostic_namespace/do_not_recommend/incorrect-locations.current.stderr
@@ -1,5 +1,5 @@
 warning: `#[diagnostic::do_not_recommend]` can only be placed on trait implementations
-  --> $DIR/incorrect-locations.rs:6:1
+  --> $DIR/incorrect-locations.rs:7:1
    |
 LL | #[diagnostic::do_not_recommend]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -7,49 +7,49 @@ LL | #[diagnostic::do_not_recommend]
    = note: `#[warn(unknown_or_malformed_diagnostic_attributes)]` on by default
 
 warning: `#[diagnostic::do_not_recommend]` can only be placed on trait implementations
-  --> $DIR/incorrect-locations.rs:10:1
+  --> $DIR/incorrect-locations.rs:11:1
    |
 LL | #[diagnostic::do_not_recommend]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 warning: `#[diagnostic::do_not_recommend]` can only be placed on trait implementations
-  --> $DIR/incorrect-locations.rs:14:1
+  --> $DIR/incorrect-locations.rs:15:1
    |
 LL | #[diagnostic::do_not_recommend]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 warning: `#[diagnostic::do_not_recommend]` can only be placed on trait implementations
-  --> $DIR/incorrect-locations.rs:18:1
+  --> $DIR/incorrect-locations.rs:19:1
    |
 LL | #[diagnostic::do_not_recommend]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 warning: `#[diagnostic::do_not_recommend]` can only be placed on trait implementations
-  --> $DIR/incorrect-locations.rs:22:1
+  --> $DIR/incorrect-locations.rs:23:1
    |
 LL | #[diagnostic::do_not_recommend]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 warning: `#[diagnostic::do_not_recommend]` can only be placed on trait implementations
-  --> $DIR/incorrect-locations.rs:26:1
+  --> $DIR/incorrect-locations.rs:27:1
    |
 LL | #[diagnostic::do_not_recommend]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 warning: `#[diagnostic::do_not_recommend]` can only be placed on trait implementations
-  --> $DIR/incorrect-locations.rs:30:1
+  --> $DIR/incorrect-locations.rs:31:1
    |
 LL | #[diagnostic::do_not_recommend]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 warning: `#[diagnostic::do_not_recommend]` can only be placed on trait implementations
-  --> $DIR/incorrect-locations.rs:34:1
+  --> $DIR/incorrect-locations.rs:35:1
    |
 LL | #[diagnostic::do_not_recommend]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 warning: `#[diagnostic::do_not_recommend]` can only be placed on trait implementations
-  --> $DIR/incorrect-locations.rs:38:1
+  --> $DIR/incorrect-locations.rs:39:1
    |
 LL | #[diagnostic::do_not_recommend]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/incorrect-locations.next.stderr b/tests/ui/diagnostic_namespace/do_not_recommend/incorrect-locations.next.stderr
index ee6ebabadd9..e348f0c8902 100644
--- a/tests/ui/diagnostic_namespace/do_not_recommend/incorrect-locations.next.stderr
+++ b/tests/ui/diagnostic_namespace/do_not_recommend/incorrect-locations.next.stderr
@@ -1,5 +1,5 @@
 warning: `#[diagnostic::do_not_recommend]` can only be placed on trait implementations
-  --> $DIR/incorrect-locations.rs:6:1
+  --> $DIR/incorrect-locations.rs:7:1
    |
 LL | #[diagnostic::do_not_recommend]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -7,49 +7,49 @@ LL | #[diagnostic::do_not_recommend]
    = note: `#[warn(unknown_or_malformed_diagnostic_attributes)]` on by default
 
 warning: `#[diagnostic::do_not_recommend]` can only be placed on trait implementations
-  --> $DIR/incorrect-locations.rs:10:1
+  --> $DIR/incorrect-locations.rs:11:1
    |
 LL | #[diagnostic::do_not_recommend]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 warning: `#[diagnostic::do_not_recommend]` can only be placed on trait implementations
-  --> $DIR/incorrect-locations.rs:14:1
+  --> $DIR/incorrect-locations.rs:15:1
    |
 LL | #[diagnostic::do_not_recommend]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 warning: `#[diagnostic::do_not_recommend]` can only be placed on trait implementations
-  --> $DIR/incorrect-locations.rs:18:1
+  --> $DIR/incorrect-locations.rs:19:1
    |
 LL | #[diagnostic::do_not_recommend]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 warning: `#[diagnostic::do_not_recommend]` can only be placed on trait implementations
-  --> $DIR/incorrect-locations.rs:22:1
+  --> $DIR/incorrect-locations.rs:23:1
    |
 LL | #[diagnostic::do_not_recommend]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 warning: `#[diagnostic::do_not_recommend]` can only be placed on trait implementations
-  --> $DIR/incorrect-locations.rs:26:1
+  --> $DIR/incorrect-locations.rs:27:1
    |
 LL | #[diagnostic::do_not_recommend]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 warning: `#[diagnostic::do_not_recommend]` can only be placed on trait implementations
-  --> $DIR/incorrect-locations.rs:30:1
+  --> $DIR/incorrect-locations.rs:31:1
    |
 LL | #[diagnostic::do_not_recommend]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 warning: `#[diagnostic::do_not_recommend]` can only be placed on trait implementations
-  --> $DIR/incorrect-locations.rs:34:1
+  --> $DIR/incorrect-locations.rs:35:1
    |
 LL | #[diagnostic::do_not_recommend]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 warning: `#[diagnostic::do_not_recommend]` can only be placed on trait implementations
-  --> $DIR/incorrect-locations.rs:38:1
+  --> $DIR/incorrect-locations.rs:39:1
    |
 LL | #[diagnostic::do_not_recommend]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/incorrect-locations.rs b/tests/ui/diagnostic_namespace/do_not_recommend/incorrect-locations.rs
index 1cf436aa2af..e716457eaed 100644
--- a/tests/ui/diagnostic_namespace/do_not_recommend/incorrect-locations.rs
+++ b/tests/ui/diagnostic_namespace/do_not_recommend/incorrect-locations.rs
@@ -2,6 +2,7 @@
 //@ revisions: current next
 //@ ignore-compare-mode-next-solver (explicit revisions)
 //@[next] compile-flags: -Znext-solver
+//@ reference: attributes.diagnostic.do_not_recommend.allowed-positions
 
 #[diagnostic::do_not_recommend]
 //~^WARN `#[diagnostic::do_not_recommend]` can only be placed
diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/nested.current.stderr b/tests/ui/diagnostic_namespace/do_not_recommend/nested.current.stderr
index b14c68d6897..cb1da8ff8be 100644
--- a/tests/ui/diagnostic_namespace/do_not_recommend/nested.current.stderr
+++ b/tests/ui/diagnostic_namespace/do_not_recommend/nested.current.stderr
@@ -1,11 +1,11 @@
 error[E0277]: the trait bound `(): Root` is not satisfied
-  --> $DIR/nested.rs:21:18
+  --> $DIR/nested.rs:22:18
    |
 LL |     needs_root::<()>();
    |                  ^^ the trait `Root` is not implemented for `()`
    |
 note: required by a bound in `needs_root`
-  --> $DIR/nested.rs:18:18
+  --> $DIR/nested.rs:19:18
    |
 LL | fn needs_root<T: Root>() {}
    |                  ^^^^ required by this bound in `needs_root`
diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/nested.next.stderr b/tests/ui/diagnostic_namespace/do_not_recommend/nested.next.stderr
index b14c68d6897..cb1da8ff8be 100644
--- a/tests/ui/diagnostic_namespace/do_not_recommend/nested.next.stderr
+++ b/tests/ui/diagnostic_namespace/do_not_recommend/nested.next.stderr
@@ -1,11 +1,11 @@
 error[E0277]: the trait bound `(): Root` is not satisfied
-  --> $DIR/nested.rs:21:18
+  --> $DIR/nested.rs:22:18
    |
 LL |     needs_root::<()>();
    |                  ^^ the trait `Root` is not implemented for `()`
    |
 note: required by a bound in `needs_root`
-  --> $DIR/nested.rs:18:18
+  --> $DIR/nested.rs:19:18
    |
 LL | fn needs_root<T: Root>() {}
    |                  ^^^^ required by this bound in `needs_root`
diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/nested.rs b/tests/ui/diagnostic_namespace/do_not_recommend/nested.rs
index 6534157d1fb..3c96c760dfb 100644
--- a/tests/ui/diagnostic_namespace/do_not_recommend/nested.rs
+++ b/tests/ui/diagnostic_namespace/do_not_recommend/nested.rs
@@ -1,6 +1,7 @@
 //@ revisions: current next
 //@ ignore-compare-mode-next-solver (explicit revisions)
 //@[next] compile-flags: -Znext-solver
+//@ reference: attributes.diagnostic.do_not_recommend.intro
 
 trait Root {}
 trait DontRecommend {}
diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/simple.current.stderr b/tests/ui/diagnostic_namespace/do_not_recommend/simple.current.stderr
index 884b13c17b8..dd425f1e6ee 100644
--- a/tests/ui/diagnostic_namespace/do_not_recommend/simple.current.stderr
+++ b/tests/ui/diagnostic_namespace/do_not_recommend/simple.current.stderr
@@ -1,11 +1,11 @@
 error[E0277]: the trait bound `*mut (): Foo` is not satisfied
-  --> $DIR/simple.rs:15:17
+  --> $DIR/simple.rs:16:17
    |
 LL |     needs_foo::<*mut ()>();
    |                 ^^^^^^^ the trait `Foo` is not implemented for `*mut ()`
    |
 note: required by a bound in `needs_foo`
-  --> $DIR/simple.rs:10:17
+  --> $DIR/simple.rs:11:17
    |
 LL | fn needs_foo<T: Foo>() {}
    |                 ^^^ required by this bound in `needs_foo`
diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/simple.next.stderr b/tests/ui/diagnostic_namespace/do_not_recommend/simple.next.stderr
index 884b13c17b8..dd425f1e6ee 100644
--- a/tests/ui/diagnostic_namespace/do_not_recommend/simple.next.stderr
+++ b/tests/ui/diagnostic_namespace/do_not_recommend/simple.next.stderr
@@ -1,11 +1,11 @@
 error[E0277]: the trait bound `*mut (): Foo` is not satisfied
-  --> $DIR/simple.rs:15:17
+  --> $DIR/simple.rs:16:17
    |
 LL |     needs_foo::<*mut ()>();
    |                 ^^^^^^^ the trait `Foo` is not implemented for `*mut ()`
    |
 note: required by a bound in `needs_foo`
-  --> $DIR/simple.rs:10:17
+  --> $DIR/simple.rs:11:17
    |
 LL | fn needs_foo<T: Foo>() {}
    |                 ^^^ required by this bound in `needs_foo`
diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/simple.rs b/tests/ui/diagnostic_namespace/do_not_recommend/simple.rs
index 6bca2b724d2..a6fa7ac7949 100644
--- a/tests/ui/diagnostic_namespace/do_not_recommend/simple.rs
+++ b/tests/ui/diagnostic_namespace/do_not_recommend/simple.rs
@@ -1,6 +1,7 @@
 //@ revisions: current next
 //@ ignore-compare-mode-next-solver (explicit revisions)
 //@[next] compile-flags: -Znext-solver
+//@ reference: attributes.diagnostic.do_not_recommend.intro
 
 trait Foo {}
 
diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/stacked.current.stderr b/tests/ui/diagnostic_namespace/do_not_recommend/stacked.current.stderr
index d8605806395..d940c3fd477 100644
--- a/tests/ui/diagnostic_namespace/do_not_recommend/stacked.current.stderr
+++ b/tests/ui/diagnostic_namespace/do_not_recommend/stacked.current.stderr
@@ -1,11 +1,11 @@
 error[E0277]: the trait bound `(): Root` is not satisfied
-  --> $DIR/stacked.rs:17:18
+  --> $DIR/stacked.rs:18:18
    |
 LL |     needs_root::<()>();
    |                  ^^ the trait `Root` is not implemented for `()`
    |
 note: required by a bound in `needs_root`
-  --> $DIR/stacked.rs:14:18
+  --> $DIR/stacked.rs:15:18
    |
 LL | fn needs_root<T: Root>() {}
    |                  ^^^^ required by this bound in `needs_root`
diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/stacked.next.stderr b/tests/ui/diagnostic_namespace/do_not_recommend/stacked.next.stderr
index d8605806395..d940c3fd477 100644
--- a/tests/ui/diagnostic_namespace/do_not_recommend/stacked.next.stderr
+++ b/tests/ui/diagnostic_namespace/do_not_recommend/stacked.next.stderr
@@ -1,11 +1,11 @@
 error[E0277]: the trait bound `(): Root` is not satisfied
-  --> $DIR/stacked.rs:17:18
+  --> $DIR/stacked.rs:18:18
    |
 LL |     needs_root::<()>();
    |                  ^^ the trait `Root` is not implemented for `()`
    |
 note: required by a bound in `needs_root`
-  --> $DIR/stacked.rs:14:18
+  --> $DIR/stacked.rs:15:18
    |
 LL | fn needs_root<T: Root>() {}
    |                  ^^^^ required by this bound in `needs_root`
diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/stacked.rs b/tests/ui/diagnostic_namespace/do_not_recommend/stacked.rs
index 842e04b9d90..fd7be35ff84 100644
--- a/tests/ui/diagnostic_namespace/do_not_recommend/stacked.rs
+++ b/tests/ui/diagnostic_namespace/do_not_recommend/stacked.rs
@@ -1,6 +1,7 @@
 //@ revisions: current next
 //@ ignore-compare-mode-next-solver (explicit revisions)
 //@[next] compile-flags: -Znext-solver
+//@ reference: attributes.diagnostic.do_not_recommend.intro
 
 trait Root {}
 trait DontRecommend {}
diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/supress_suggestions_in_help.current.stderr b/tests/ui/diagnostic_namespace/do_not_recommend/supress_suggestions_in_help.current.stderr
index 95ccbb92a89..0b07b073172 100644
--- a/tests/ui/diagnostic_namespace/do_not_recommend/supress_suggestions_in_help.current.stderr
+++ b/tests/ui/diagnostic_namespace/do_not_recommend/supress_suggestions_in_help.current.stderr
@@ -1,5 +1,5 @@
 error[E0277]: the trait bound `(): Foo` is not satisfied
-  --> $DIR/supress_suggestions_in_help.rs:21:11
+  --> $DIR/supress_suggestions_in_help.rs:22:11
    |
 LL |     check(());
    |     ----- ^^ the trait `Foo` is not implemented for `()`
@@ -8,7 +8,7 @@ LL |     check(());
    |
    = help: the trait `Foo` is implemented for `i32`
 note: required by a bound in `check`
-  --> $DIR/supress_suggestions_in_help.rs:18:18
+  --> $DIR/supress_suggestions_in_help.rs:19:18
    |
 LL | fn check(a: impl Foo) {}
    |                  ^^^ required by this bound in `check`
diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/supress_suggestions_in_help.next.stderr b/tests/ui/diagnostic_namespace/do_not_recommend/supress_suggestions_in_help.next.stderr
index 95ccbb92a89..0b07b073172 100644
--- a/tests/ui/diagnostic_namespace/do_not_recommend/supress_suggestions_in_help.next.stderr
+++ b/tests/ui/diagnostic_namespace/do_not_recommend/supress_suggestions_in_help.next.stderr
@@ -1,5 +1,5 @@
 error[E0277]: the trait bound `(): Foo` is not satisfied
-  --> $DIR/supress_suggestions_in_help.rs:21:11
+  --> $DIR/supress_suggestions_in_help.rs:22:11
    |
 LL |     check(());
    |     ----- ^^ the trait `Foo` is not implemented for `()`
@@ -8,7 +8,7 @@ LL |     check(());
    |
    = help: the trait `Foo` is implemented for `i32`
 note: required by a bound in `check`
-  --> $DIR/supress_suggestions_in_help.rs:18:18
+  --> $DIR/supress_suggestions_in_help.rs:19:18
    |
 LL | fn check(a: impl Foo) {}
    |                  ^^^ required by this bound in `check`
diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/supress_suggestions_in_help.rs b/tests/ui/diagnostic_namespace/do_not_recommend/supress_suggestions_in_help.rs
index 2c7c1516123..04cf8243a67 100644
--- a/tests/ui/diagnostic_namespace/do_not_recommend/supress_suggestions_in_help.rs
+++ b/tests/ui/diagnostic_namespace/do_not_recommend/supress_suggestions_in_help.rs
@@ -1,6 +1,7 @@
 //@ revisions: current next
 //@ ignore-compare-mode-next-solver (explicit revisions)
 //@[next] compile-flags: -Znext-solver
+//@ reference: attributes.diagnostic.do_not_recommend.intro
 
 trait Foo {}
 
diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/type_mismatch.current.stderr b/tests/ui/diagnostic_namespace/do_not_recommend/type_mismatch.current.stderr
index b53febbb71a..31a1ae991ec 100644
--- a/tests/ui/diagnostic_namespace/do_not_recommend/type_mismatch.current.stderr
+++ b/tests/ui/diagnostic_namespace/do_not_recommend/type_mismatch.current.stderr
@@ -1,11 +1,11 @@
 error[E0277]: Very important message!
-  --> $DIR/type_mismatch.rs:23:14
+  --> $DIR/type_mismatch.rs:24:14
    |
 LL |     verify::<u8>();
    |              ^^ the trait `TheImportantOne` is not implemented for `u8`
    |
 note: required by a bound in `verify`
-  --> $DIR/type_mismatch.rs:20:14
+  --> $DIR/type_mismatch.rs:21:14
    |
 LL | fn verify<T: TheImportantOne>() {}
    |              ^^^^^^^^^^^^^^^ required by this bound in `verify`
diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/type_mismatch.next.stderr b/tests/ui/diagnostic_namespace/do_not_recommend/type_mismatch.next.stderr
index b53febbb71a..31a1ae991ec 100644
--- a/tests/ui/diagnostic_namespace/do_not_recommend/type_mismatch.next.stderr
+++ b/tests/ui/diagnostic_namespace/do_not_recommend/type_mismatch.next.stderr
@@ -1,11 +1,11 @@
 error[E0277]: Very important message!
-  --> $DIR/type_mismatch.rs:23:14
+  --> $DIR/type_mismatch.rs:24:14
    |
 LL |     verify::<u8>();
    |              ^^ the trait `TheImportantOne` is not implemented for `u8`
    |
 note: required by a bound in `verify`
-  --> $DIR/type_mismatch.rs:20:14
+  --> $DIR/type_mismatch.rs:21:14
    |
 LL | fn verify<T: TheImportantOne>() {}
    |              ^^^^^^^^^^^^^^^ required by this bound in `verify`
diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/type_mismatch.rs b/tests/ui/diagnostic_namespace/do_not_recommend/type_mismatch.rs
index 7f30fdb06c7..b5bd14745cd 100644
--- a/tests/ui/diagnostic_namespace/do_not_recommend/type_mismatch.rs
+++ b/tests/ui/diagnostic_namespace/do_not_recommend/type_mismatch.rs
@@ -1,6 +1,7 @@
 //@ revisions: current next
 //@ ignore-compare-mode-next-solver (explicit revisions)
 //@[next] compile-flags: -Znext-solver
+//@ reference: attributes.diagnostic.do_not_recommend.intro
 
 #[diagnostic::on_unimplemented(message = "Very important message!")]
 trait TheImportantOne {}
diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/with_lifetime.current.stderr b/tests/ui/diagnostic_namespace/do_not_recommend/with_lifetime.current.stderr
index a8429ff60f8..7e348842e19 100644
--- a/tests/ui/diagnostic_namespace/do_not_recommend/with_lifetime.current.stderr
+++ b/tests/ui/diagnostic_namespace/do_not_recommend/with_lifetime.current.stderr
@@ -1,5 +1,5 @@
 error: lifetime may not live long enough
-  --> $DIR/with_lifetime.rs:17:5
+  --> $DIR/with_lifetime.rs:18:5
    |
 LL | fn foo<'a>(a: &'a ()) {
    |        -- lifetime `'a` defined here
diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/with_lifetime.next.stderr b/tests/ui/diagnostic_namespace/do_not_recommend/with_lifetime.next.stderr
index a8429ff60f8..7e348842e19 100644
--- a/tests/ui/diagnostic_namespace/do_not_recommend/with_lifetime.next.stderr
+++ b/tests/ui/diagnostic_namespace/do_not_recommend/with_lifetime.next.stderr
@@ -1,5 +1,5 @@
 error: lifetime may not live long enough
-  --> $DIR/with_lifetime.rs:17:5
+  --> $DIR/with_lifetime.rs:18:5
    |
 LL | fn foo<'a>(a: &'a ()) {
    |        -- lifetime `'a` defined here
diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/with_lifetime.rs b/tests/ui/diagnostic_namespace/do_not_recommend/with_lifetime.rs
index 6a67d83d5fe..98916ed061f 100644
--- a/tests/ui/diagnostic_namespace/do_not_recommend/with_lifetime.rs
+++ b/tests/ui/diagnostic_namespace/do_not_recommend/with_lifetime.rs
@@ -1,6 +1,7 @@
 //@ revisions: current next
 //@ ignore-compare-mode-next-solver (explicit revisions)
 //@[next] compile-flags: -Znext-solver
+//@ reference: attributes.diagnostic.do_not_recommend.intro
 
 trait Root {}
 trait DontRecommend {}
diff --git a/tests/ui/implied-bounds/impl-implied-bounds-compatibility-unnormalized.stderr b/tests/ui/implied-bounds/impl-implied-bounds-compatibility-unnormalized.stderr
index f498257e12f..f8ee6fef824 100644
--- a/tests/ui/implied-bounds/impl-implied-bounds-compatibility-unnormalized.stderr
+++ b/tests/ui/implied-bounds/impl-implied-bounds-compatibility-unnormalized.stderr
@@ -1,4 +1,4 @@
-error[E0495]: cannot infer an appropriate lifetime for lifetime parameter 's in generic type due to conflicting requirements
+error[E0803]: cannot infer an appropriate lifetime for lifetime parameter 's in generic type due to conflicting requirements
   --> $DIR/impl-implied-bounds-compatibility-unnormalized.rs:11:5
    |
 LL |     fn get<'s>(s: &'s str, _: <&'static &'s () as Project>::Ty) -> &'static str {
@@ -25,4 +25,4 @@ LL |     fn get<'s>(s: &'s str, _: <&'static &'s () as Project>::Ty) -> &'static
 
 error: aborting due to 1 previous error
 
-For more information about this error, try `rustc --explain E0495`.
+For more information about this error, try `rustc --explain E0803`.
diff --git a/tests/ui/issues/issue-20831-debruijn.stderr b/tests/ui/issues/issue-20831-debruijn.stderr
index fe310998f09..bed75ed6ba2 100644
--- a/tests/ui/issues/issue-20831-debruijn.stderr
+++ b/tests/ui/issues/issue-20831-debruijn.stderr
@@ -1,4 +1,4 @@
-error[E0495]: cannot infer an appropriate lifetime for lifetime parameter `'a` due to conflicting requirements
+error[E0803]: cannot infer an appropriate lifetime for lifetime parameter `'a` due to conflicting requirements
   --> $DIR/issue-20831-debruijn.rs:28:33
    |
 LL |     fn subscribe(&mut self, t : Box<dyn Subscriber<Input=<Self as Publisher>::Output> + 'a>) {
@@ -48,4 +48,4 @@ LL |     fn subscribe(&mut self, t : Box<dyn Subscriber<Input=<Self as Publisher
 
 error: aborting due to 3 previous errors
 
-For more information about this error, try `rustc --explain E0495`.
+For more information about this error, try `rustc --explain E0803`.
diff --git a/tests/ui/nll/normalization-bounds-error.stderr b/tests/ui/nll/normalization-bounds-error.stderr
index d4254881863..47d2663313d 100644
--- a/tests/ui/nll/normalization-bounds-error.stderr
+++ b/tests/ui/nll/normalization-bounds-error.stderr
@@ -1,4 +1,4 @@
-error[E0495]: cannot infer an appropriate lifetime for lifetime parameter `'d` due to conflicting requirements
+error[E0803]: cannot infer an appropriate lifetime for lifetime parameter `'d` due to conflicting requirements
   --> $DIR/normalization-bounds-error.rs:12:31
    |
 LL | fn visit_seq<'d, 'a: 'd>() -> <&'a () as Visitor<'d>>::Value {}
@@ -36,4 +36,4 @@ LL | fn visit_seq<'d, 'a: 'd>() -> <&'a () as Visitor<'d>>::Value {}
 
 error: aborting due to 2 previous errors
 
-For more information about this error, try `rustc --explain E0495`.
+For more information about this error, try `rustc --explain E0803`.
diff --git a/tests/ui/process/process-sigpipe.rs b/tests/ui/process/process-sigpipe.rs
index 453e53379fc..3ecf271599d 100644
--- a/tests/ui/process/process-sigpipe.rs
+++ b/tests/ui/process/process-sigpipe.rs
@@ -9,9 +9,9 @@
 // Make sure that these behaviors don't get inherited to children
 // spawned via std::process, since they're needed for traditional UNIX
 // filter behavior.
-// This test checks that `while echo y ; do : ; done | head` terminates
-// (instead of running forever), and that it does not print an error
-// message about a broken pipe.
+// This test checks that `yes` or `while echo y ; do : ; done | head`
+// terminates (instead of running forever), and that it does not print an
+// error message about a broken pipe.
 
 //@ ignore-vxworks no 'sh'
 //@ ignore-fuchsia no 'sh'
@@ -22,14 +22,21 @@ use std::process;
 use std::thread;
 
 fn main() {
-    // Just in case `yes` doesn't check for EPIPE...
+    // Just in case `yes` or `while-echo` doesn't check for EPIPE...
     thread::spawn(|| {
         thread::sleep_ms(5000);
         process::exit(1);
     });
+    // QNX Neutrino does not have `yes`. Therefore, use `while-echo` for `nto`
+    // and `yes` for other platforms.
+    let command = if cfg!(target_os = "nto") {
+        "while echo y ; do : ; done | head"
+    } else {
+        "yes | head"
+    };
     let output = process::Command::new("sh")
         .arg("-c")
-        .arg("while echo y ; do : ; done | head")
+        .arg(command)
         .output()
         .unwrap();
     assert!(output.status.success());
diff --git a/tests/ui/regions/regions-normalize-in-where-clause-list.stderr b/tests/ui/regions/regions-normalize-in-where-clause-list.stderr
index 2e76333e26f..ca9ceeeeff3 100644
--- a/tests/ui/regions/regions-normalize-in-where-clause-list.stderr
+++ b/tests/ui/regions/regions-normalize-in-where-clause-list.stderr
@@ -1,4 +1,4 @@
-error[E0495]: cannot infer an appropriate lifetime for lifetime parameter `'a` due to conflicting requirements
+error[E0803]: cannot infer an appropriate lifetime for lifetime parameter `'a` due to conflicting requirements
   --> $DIR/regions-normalize-in-where-clause-list.rs:24:4
    |
 LL | fn bar<'a, 'b>()
@@ -24,4 +24,4 @@ LL | fn bar<'a, 'b>()
 
 error: aborting due to 1 previous error
 
-For more information about this error, try `rustc --explain E0495`.
+For more information about this error, try `rustc --explain E0803`.
diff --git a/tests/ui/regions/resolve-re-error-ice.stderr b/tests/ui/regions/resolve-re-error-ice.stderr
index 41c5f0fa92e..f463a97c5bc 100644
--- a/tests/ui/regions/resolve-re-error-ice.stderr
+++ b/tests/ui/regions/resolve-re-error-ice.stderr
@@ -1,4 +1,4 @@
-error[E0495]: cannot infer an appropriate lifetime for lifetime parameter '_ in generic type due to conflicting requirements
+error[E0803]: cannot infer an appropriate lifetime for lifetime parameter '_ in generic type due to conflicting requirements
   --> $DIR/resolve-re-error-ice.rs:12:5
    |
 LL |     fn key_set(&self) -> Subject<'a, Keys<K, V>, (), R> {
@@ -34,4 +34,4 @@ LL | struct Subject<'a, T, V, R>(PhantomData<(&'a T, V, R)>);
 
 error: aborting due to 1 previous error
 
-For more information about this error, try `rustc --explain E0495`.
+For more information about this error, try `rustc --explain E0803`.
diff --git a/tests/ui/static/static-lifetime.stderr b/tests/ui/static/static-lifetime.stderr
index 7a956dbfeef..9b5869fd0dc 100644
--- a/tests/ui/static/static-lifetime.stderr
+++ b/tests/ui/static/static-lifetime.stderr
@@ -11,7 +11,7 @@ LL | impl<'a, A: Clone> Arbitrary for ::std::borrow::Cow<'a, A> {}
    |      ^^
    = note: but lifetime parameter must outlive the static lifetime
 
-error[E0495]: cannot infer an appropriate lifetime for lifetime parameter `'a` due to conflicting requirements
+error[E0803]: cannot infer an appropriate lifetime for lifetime parameter `'a` due to conflicting requirements
   --> $DIR/static-lifetime.rs:3:34
    |
 LL | impl<'a, A: Clone> Arbitrary for ::std::borrow::Cow<'a, A> {}
@@ -38,5 +38,5 @@ LL | impl<'a, A: Clone> Arbitrary for ::std::borrow::Cow<'a, A> {}
 
 error: aborting due to 2 previous errors
 
-Some errors have detailed explanations: E0478, E0495.
+Some errors have detailed explanations: E0478, E0803.
 For more information about an error, try `rustc --explain E0478`.
diff --git a/tests/ui/traits/impl-of-supertrait-has-wrong-lifetime-parameters.stderr b/tests/ui/traits/impl-of-supertrait-has-wrong-lifetime-parameters.stderr
index 8bf8536c74e..4e324209fe9 100644
--- a/tests/ui/traits/impl-of-supertrait-has-wrong-lifetime-parameters.stderr
+++ b/tests/ui/traits/impl-of-supertrait-has-wrong-lifetime-parameters.stderr
@@ -1,4 +1,4 @@
-error[E0495]: cannot infer an appropriate lifetime for lifetime parameter `'b` due to conflicting requirements
+error[E0803]: cannot infer an appropriate lifetime for lifetime parameter `'b` due to conflicting requirements
   --> $DIR/impl-of-supertrait-has-wrong-lifetime-parameters.rs:24:28
    |
 LL | impl<'a,'b> T2<'a, 'b> for S<'a, 'b> {
@@ -24,4 +24,4 @@ LL | impl<'a,'b> T2<'a, 'b> for S<'a, 'b> {
 
 error: aborting due to 1 previous error
 
-For more information about this error, try `rustc --explain E0495`.
+For more information about this error, try `rustc --explain E0803`.
diff --git a/tests/ui/type-alias-impl-trait/closure_wf_outlives.stderr b/tests/ui/type-alias-impl-trait/closure_wf_outlives.stderr
index 04288112fa8..ae00d3fc667 100644
--- a/tests/ui/type-alias-impl-trait/closure_wf_outlives.stderr
+++ b/tests/ui/type-alias-impl-trait/closure_wf_outlives.stderr
@@ -15,7 +15,7 @@ note: but lifetime parameter must outlive the lifetime `'b` as defined here
 LL |     type Opaque<'a, 'b> = impl Sized + 'a + 'b;
    |                     ^^
 
-error[E0495]: cannot infer an appropriate lifetime due to conflicting requirements
+error[E0803]: cannot infer an appropriate lifetime due to conflicting requirements
   --> $DIR/closure_wf_outlives.rs:34:9
    |
 LL |         || {}
@@ -63,5 +63,5 @@ LL |     type Opaque<T: 'static> = impl Sized;
 
 error: aborting due to 3 previous errors
 
-Some errors have detailed explanations: E0310, E0478, E0495.
+Some errors have detailed explanations: E0310, E0478, E0803.
 For more information about an error, try `rustc --explain E0310`.