diff --git a/Cargo.lock b/Cargo.lock
index f0c6e371c38be..716f4d7501467 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -221,7 +221,6 @@ dependencies = [
  "getopts",
  "ignore",
  "libc",
- "num_cpus",
  "once_cell",
  "opener",
  "pretty_assertions",
@@ -249,7 +248,6 @@ dependencies = [
  "anyhow",
  "flate2",
  "hex 0.4.2",
- "num_cpus",
  "rayon",
  "serde",
  "serde_json",
@@ -4241,7 +4239,6 @@ name = "rustc_session"
 version = "0.0.0"
 dependencies = [
  "getopts",
- "num_cpus",
  "rustc_ast",
  "rustc_data_structures",
  "rustc_errors",
diff --git a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
index 4502d15f36fa1..684a3ced5a070 100644
--- a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
@@ -5,16 +5,21 @@ use rustc_errors::{Applicability, Diagnostic, DiagnosticBuilder, ErrorGuaranteed
 use rustc_hir as hir;
 use rustc_hir::def_id::DefId;
 use rustc_hir::{AsyncGeneratorKind, GeneratorKind};
+use rustc_infer::infer::TyCtxtInferExt;
+use rustc_infer::traits::ObligationCause;
 use rustc_middle::mir::{
     self, AggregateKind, BindingForm, BorrowKind, ClearCrossCrate, ConstraintCategory,
     FakeReadCause, LocalDecl, LocalInfo, LocalKind, Location, Operand, Place, PlaceRef,
     ProjectionElem, Rvalue, Statement, StatementKind, Terminator, TerminatorKind, VarBindingForm,
 };
-use rustc_middle::ty::{self, suggest_constraining_type_param, Ty};
+use rustc_middle::ty::{
+    self, suggest_constraining_type_param, suggest_constraining_type_params, PredicateKind, Ty,
+};
 use rustc_mir_dataflow::move_paths::{InitKind, MoveOutIndex, MovePathIndex};
 use rustc_span::symbol::sym;
 use rustc_span::{BytePos, MultiSpan, Span, DUMMY_SP};
 use rustc_trait_selection::infer::InferCtxtExt;
+use rustc_trait_selection::traits::TraitEngineExt as _;
 
 use crate::borrow_set::TwoPhaseActivation;
 use crate::borrowck_errors;
@@ -423,7 +428,63 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                             None,
                         );
                     }
+                } else {
+                    // Try to find predicates on *generic params* that would allow copying `ty`
+
+                    let tcx = self.infcx.tcx;
+                    let generics = tcx.generics_of(self.mir_def_id());
+                    if let Some(hir_generics) = tcx
+                        .typeck_root_def_id(self.mir_def_id().to_def_id())
+                        .as_local()
+                        .and_then(|def_id| tcx.hir().get_generics(def_id))
+                    {
+                        let predicates: Result<Vec<_>, _> = tcx.infer_ctxt().enter(|infcx| {
+                            let mut fulfill_cx =
+                                <dyn rustc_infer::traits::TraitEngine<'_>>::new(infcx.tcx);
+
+                            let copy_did = infcx.tcx.lang_items().copy_trait().unwrap();
+                            let cause = ObligationCause::new(
+                                span,
+                                self.mir_hir_id(),
+                                rustc_infer::traits::ObligationCauseCode::MiscObligation,
+                            );
+                            fulfill_cx.register_bound(&infcx, self.param_env, ty, copy_did, cause);
+                            let errors = fulfill_cx.select_where_possible(&infcx);
+
+                            // Only emit suggestion if all required predicates are on generic
+                            errors
+                                .into_iter()
+                                .map(|err| match err.obligation.predicate.kind().skip_binder() {
+                                    PredicateKind::Trait(predicate) => {
+                                        match predicate.self_ty().kind() {
+                                            ty::Param(param_ty) => Ok((
+                                                generics.type_param(param_ty, tcx),
+                                                predicate
+                                                    .trait_ref
+                                                    .print_only_trait_path()
+                                                    .to_string(),
+                                            )),
+                                            _ => Err(()),
+                                        }
+                                    }
+                                    _ => Err(()),
+                                })
+                                .collect()
+                        });
+
+                        if let Ok(predicates) = predicates {
+                            suggest_constraining_type_params(
+                                tcx,
+                                hir_generics,
+                                &mut err,
+                                predicates.iter().map(|(param, constraint)| {
+                                    (param.name.as_str(), &**constraint, None)
+                                }),
+                            );
+                        }
+                    }
                 }
+
                 let span = if let Some(local) = place.as_local() {
                     let decl = &self.body.local_decls[local];
                     Some(decl.source_info.span)
diff --git a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
index 4a8894983b98d..6e9e0332faf60 100644
--- a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
+++ b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
@@ -576,12 +576,12 @@ pub enum PassKind {
     Module,
 }
 
-/// LLVMRustThinLTOData
+// LLVMRustThinLTOData
 extern "C" {
     pub type ThinLTOData;
 }
 
-/// LLVMRustThinLTOBuffer
+// LLVMRustThinLTOBuffer
 extern "C" {
     pub type ThinLTOBuffer;
 }
diff --git a/compiler/rustc_const_eval/src/interpret/intrinsics.rs b/compiler/rustc_const_eval/src/interpret/intrinsics.rs
index d6f856a6f0a70..bf7e811c76f8e 100644
--- a/compiler/rustc_const_eval/src/interpret/intrinsics.rs
+++ b/compiler/rustc_const_eval/src/interpret/intrinsics.rs
@@ -500,15 +500,9 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
         // `x % y != 0` or `y == 0` or `x == T::MIN && y == -1`.
         // First, check x % y != 0 (or if that computation overflows).
         let (res, overflow, _ty) = self.overflowing_binary_op(BinOp::Rem, &a, &b)?;
-        if overflow || res.assert_bits(a.layout.size) != 0 {
-            // Then, check if `b` is -1, which is the "MIN / -1" case.
-            let minus1 = Scalar::from_int(-1, dest.layout.size);
-            let b_scalar = b.to_scalar().unwrap();
-            if b_scalar == minus1 {
-                throw_ub_format!("exact_div: result of dividing MIN by -1 cannot be represented")
-            } else {
-                throw_ub_format!("exact_div: {} cannot be divided by {} without remainder", a, b,)
-            }
+        assert!(!overflow); // All overflow is UB, so this should never return on overflow.
+        if res.assert_bits(a.layout.size) != 0 {
+            throw_ub_format!("exact_div: {} cannot be divided by {} without remainder", a, b)
         }
         // `Rem` says this is all right, so we can let `Div` do its job.
         self.binop_ignore_overflow(BinOp::Div, &a, &b, dest)
diff --git a/compiler/rustc_const_eval/src/interpret/operator.rs b/compiler/rustc_const_eval/src/interpret/operator.rs
index 48c90e1881a9a..079ce9f07b8e1 100644
--- a/compiler/rustc_const_eval/src/interpret/operator.rs
+++ b/compiler/rustc_const_eval/src/interpret/operator.rs
@@ -196,16 +196,20 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                 _ => None,
             };
             if let Some(op) = op {
+                let l = self.sign_extend(l, left_layout) as i128;
                 let r = self.sign_extend(r, right_layout) as i128;
-                // We need a special check for overflowing remainder:
-                // "int_min % -1" overflows and returns 0, but after casting things to a larger int
-                // type it does *not* overflow nor give an unrepresentable result!
-                if bin_op == Rem {
-                    if r == -1 && l == (1 << (size.bits() - 1)) {
-                        return Ok((Scalar::from_int(0, size), true, left_layout.ty));
+
+                // We need a special check for overflowing Rem and Div since they are *UB*
+                // on overflow, which can happen with "int_min $OP -1".
+                if matches!(bin_op, Rem | Div) {
+                    if l == size.signed_int_min() && r == -1 {
+                        if bin_op == Rem {
+                            throw_ub!(RemainderOverflow)
+                        } else {
+                            throw_ub!(DivisionOverflow)
+                        }
                     }
                 }
-                let l = self.sign_extend(l, left_layout) as i128;
 
                 let (result, oflo) = op(l, r);
                 // This may be out-of-bounds for the result type, so we have to truncate ourselves.
diff --git a/compiler/rustc_lint/src/builtin.rs b/compiler/rustc_lint/src/builtin.rs
index 46b90baa5858a..72b8d8bb297a6 100644
--- a/compiler/rustc_lint/src/builtin.rs
+++ b/compiler/rustc_lint/src/builtin.rs
@@ -1086,6 +1086,16 @@ impl EarlyLintPass for UnusedDocComment {
     fn check_generic_param(&mut self, cx: &EarlyContext<'_>, param: &ast::GenericParam) {
         warn_if_doc(cx, param.ident.span, "generic parameters", &param.attrs);
     }
+
+    fn check_block(&mut self, cx: &EarlyContext<'_>, block: &ast::Block) {
+        warn_if_doc(cx, block.span, "block", &block.attrs());
+    }
+
+    fn check_item(&mut self, cx: &EarlyContext<'_>, item: &ast::Item) {
+        if let ast::ItemKind::ForeignMod(_) = item.kind {
+            warn_if_doc(cx, item.span, "extern block", &item.attrs);
+        }
+    }
 }
 
 declare_lint! {
diff --git a/compiler/rustc_middle/src/lib.rs b/compiler/rustc_middle/src/lib.rs
index 7ca564f29e659..f977b0fffebb6 100644
--- a/compiler/rustc_middle/src/lib.rs
+++ b/compiler/rustc_middle/src/lib.rs
@@ -56,6 +56,7 @@
 #![feature(nonzero_ops)]
 #![feature(unwrap_infallible)]
 #![feature(decl_macro)]
+#![feature(drain_filter)]
 #![recursion_limit = "512"]
 #![allow(rustc::potential_query_instability)]
 
diff --git a/compiler/rustc_middle/src/mir/interpret/error.rs b/compiler/rustc_middle/src/mir/interpret/error.rs
index 98cb90296a521..e524625f96646 100644
--- a/compiler/rustc_middle/src/mir/interpret/error.rs
+++ b/compiler/rustc_middle/src/mir/interpret/error.rs
@@ -233,6 +233,10 @@ pub enum UndefinedBehaviorInfo<'tcx> {
     DivisionByZero,
     /// Something was "remainded" by 0 (x % 0).
     RemainderByZero,
+    /// Signed division overflowed (INT_MIN / -1).
+    DivisionOverflow,
+    /// Signed remainder overflowed (INT_MIN % -1).
+    RemainderOverflow,
     /// Overflowing inbounds pointer arithmetic.
     PointerArithOverflow,
     /// Invalid metadata in a wide pointer (using `str` to avoid allocations).
@@ -310,6 +314,8 @@ impl fmt::Display for UndefinedBehaviorInfo<'_> {
             }
             DivisionByZero => write!(f, "dividing by zero"),
             RemainderByZero => write!(f, "calculating the remainder with a divisor of zero"),
+            DivisionOverflow => write!(f, "overflow in signed division (dividing MIN by -1)"),
+            RemainderOverflow => write!(f, "overflow in signed remainder (dividing MIN by -1)"),
             PointerArithOverflow => write!(f, "overflowing in-bounds pointer arithmetic"),
             InvalidMeta(msg) => write!(f, "invalid metadata in wide pointer: {}", msg),
             InvalidVtableDropFn(sig) => write!(
diff --git a/compiler/rustc_middle/src/ty/diagnostics.rs b/compiler/rustc_middle/src/ty/diagnostics.rs
index 58cf9fa7a8943..99a3d4c7fe4f7 100644
--- a/compiler/rustc_middle/src/ty/diagnostics.rs
+++ b/compiler/rustc_middle/src/ty/diagnostics.rs
@@ -7,6 +7,7 @@ use crate::ty::{
     ProjectionTy, Term, Ty, TyCtxt, TypeAndMut,
 };
 
+use rustc_data_structures::fx::FxHashMap;
 use rustc_errors::{Applicability, Diagnostic};
 use rustc_hir as hir;
 use rustc_hir::def_id::DefId;
@@ -157,9 +158,17 @@ pub fn suggest_arbitrary_trait_bound(
     true
 }
 
+#[derive(Debug)]
+enum SuggestChangingConstraintsMessage<'a> {
+    RestrictBoundFurther,
+    RestrictType { ty: &'a str },
+    RestrictTypeFurther { ty: &'a str },
+    RemovingQSized,
+}
+
 fn suggest_removing_unsized_bound(
     generics: &hir::Generics<'_>,
-    err: &mut Diagnostic,
+    suggestions: &mut Vec<(Span, String, SuggestChangingConstraintsMessage<'_>)>,
     param_name: &str,
     param: &hir::GenericParam<'_>,
     def_id: Option<DefId>,
@@ -221,13 +230,12 @@ fn suggest_removing_unsized_bound(
                         //             ^^^^^^^^^
                         (_, pos, _, _) => bounds[pos - 1].span().shrink_to_hi().to(bound.span()),
                     };
-                    err.span_suggestion_verbose(
+
+                    suggestions.push((
                         sp,
-                        "consider removing the `?Sized` bound to make the \
-                            type parameter `Sized`",
                         String::new(),
-                        Applicability::MaybeIncorrect,
-                    );
+                        SuggestChangingConstraintsMessage::RemovingQSized,
+                    ));
                 }
             }
             _ => {}
@@ -249,13 +257,12 @@ fn suggest_removing_unsized_bound(
                     //       ^^^^^^^^^
                     (_, pos) => param.bounds[pos - 1].span().shrink_to_hi().to(bound.span()),
                 };
-                err.span_suggestion_verbose(
+
+                suggestions.push((
                     sp,
-                    "consider removing the `?Sized` bound to make the type parameter \
-                        `Sized`",
                     String::new(),
-                    Applicability::MaybeIncorrect,
-                );
+                    SuggestChangingConstraintsMessage::RemovingQSized,
+                ));
             }
             _ => {}
         }
@@ -271,184 +278,249 @@ pub fn suggest_constraining_type_param(
     constraint: &str,
     def_id: Option<DefId>,
 ) -> bool {
-    let param = generics.params.iter().find(|p| p.name.ident().as_str() == param_name);
+    suggest_constraining_type_params(
+        tcx,
+        generics,
+        err,
+        [(param_name, constraint, def_id)].into_iter(),
+    )
+}
 
-    let Some(param) = param else {
-        return false;
-    };
+/// Suggest restricting a type param with a new bound.
+pub fn suggest_constraining_type_params<'a>(
+    tcx: TyCtxt<'_>,
+    generics: &hir::Generics<'_>,
+    err: &mut Diagnostic,
+    param_names_and_constraints: impl Iterator<Item = (&'a str, &'a str, Option<DefId>)>,
+) -> bool {
+    let mut grouped = FxHashMap::default();
+    param_names_and_constraints.for_each(|(param_name, constraint, def_id)| {
+        grouped.entry(param_name).or_insert(Vec::new()).push((constraint, def_id))
+    });
 
-    const MSG_RESTRICT_BOUND_FURTHER: &str = "consider further restricting this bound";
-    let msg_restrict_type = format!("consider restricting type parameter `{}`", param_name);
-    let msg_restrict_type_further =
-        format!("consider further restricting type parameter `{}`", param_name);
+    let mut applicability = Applicability::MachineApplicable;
+    let mut suggestions = Vec::new();
 
-    if def_id == tcx.lang_items().sized_trait() {
-        // Type parameters are already `Sized` by default.
-        err.span_label(param.span, &format!("this type parameter needs to be `{}`", constraint));
-        suggest_removing_unsized_bound(generics, err, param_name, param, def_id);
-        return true;
-    }
-    let mut suggest_restrict = |span| {
-        err.span_suggestion_verbose(
-            span,
-            MSG_RESTRICT_BOUND_FURTHER,
-            format!(" + {}", constraint),
-            Applicability::MachineApplicable,
-        );
-    };
+    for (param_name, mut constraints) in grouped {
+        let param = generics.params.iter().find(|p| p.name.ident().as_str() == param_name);
+        let Some(param) = param else { return false };
 
-    if param_name.starts_with("impl ") {
-        // If there's an `impl Trait` used in argument position, suggest
-        // restricting it:
-        //
-        //   fn foo(t: impl Foo) { ... }
-        //             --------
-        //             |
-        //             help: consider further restricting this bound with `+ Bar`
-        //
-        // Suggestion for tools in this case is:
-        //
-        //   fn foo(t: impl Foo) { ... }
-        //             --------
-        //             |
-        //             replace with: `impl Foo + Bar`
-
-        suggest_restrict(param.span.shrink_to_hi());
-        return true;
-    }
+        {
+            let mut sized_constraints =
+                constraints.drain_filter(|(_, def_id)| *def_id == tcx.lang_items().sized_trait());
+            if let Some((constraint, def_id)) = sized_constraints.next() {
+                applicability = Applicability::MaybeIncorrect;
 
-    if generics.where_clause.predicates.is_empty()
-        // Given `trait Base<T = String>: Super<T>` where `T: Copy`, suggest restricting in the
-        // `where` clause instead of `trait Base<T: Copy = String>: Super<T>`.
-        && !matches!(param.kind, hir::GenericParamKind::Type { default: Some(_), .. })
-    {
-        if let Some(span) = param.bounds_span_for_suggestions() {
-            // If user has provided some bounds, suggest restricting them:
+                err.span_label(
+                    param.span,
+                    &format!("this type parameter needs to be `{}`", constraint),
+                );
+                suggest_removing_unsized_bound(
+                    generics,
+                    &mut suggestions,
+                    param_name,
+                    param,
+                    def_id,
+                );
+            }
+        }
+
+        if constraints.is_empty() {
+            continue;
+        }
+
+        let constraint = constraints.iter().map(|&(c, _)| c).collect::<Vec<_>>().join(" + ");
+        let mut suggest_restrict = |span| {
+            suggestions.push((
+                span,
+                format!(" + {}", constraint),
+                SuggestChangingConstraintsMessage::RestrictBoundFurther,
+            ))
+        };
+
+        if param_name.starts_with("impl ") {
+            // If there's an `impl Trait` used in argument position, suggest
+            // restricting it:
             //
-            //   fn foo<T: Foo>(t: T) { ... }
-            //             ---
+            //   fn foo(t: impl Foo) { ... }
+            //             --------
             //             |
             //             help: consider further restricting this bound with `+ Bar`
             //
             // Suggestion for tools in this case is:
             //
-            //   fn foo<T: Foo>(t: T) { ... }
-            //          --
-            //          |
-            //          replace with: `T: Bar +`
-            suggest_restrict(span);
-        } else {
-            // If user hasn't provided any bounds, suggest adding a new one:
-            //
-            //   fn foo<T>(t: T) { ... }
-            //          - help: consider restricting this type parameter with `T: Foo`
-            err.span_suggestion_verbose(
-                param.span.shrink_to_hi(),
-                &msg_restrict_type,
-                format!(": {}", constraint),
-                Applicability::MachineApplicable,
-            );
+            //   fn foo(t: impl Foo) { ... }
+            //             --------
+            //             |
+            //             replace with: `impl Foo + Bar`
+
+            suggest_restrict(param.span.shrink_to_hi());
+            continue;
         }
 
-        true
-    } else {
-        // This part is a bit tricky, because using the `where` clause user can
-        // provide zero, one or many bounds for the same type parameter, so we
-        // have following cases to consider:
-        //
-        // 1) When the type parameter has been provided zero bounds
-        //
-        //    Message:
-        //      fn foo<X, Y>(x: X, y: Y) where Y: Foo { ... }
-        //             - help: consider restricting this type parameter with `where X: Bar`
-        //
-        //    Suggestion:
-        //      fn foo<X, Y>(x: X, y: Y) where Y: Foo { ... }
-        //                                           - insert: `, X: Bar`
-        //
-        //
-        // 2) When the type parameter has been provided one bound
-        //
-        //    Message:
-        //      fn foo<T>(t: T) where T: Foo { ... }
-        //                            ^^^^^^
-        //                            |
-        //                            help: consider further restricting this bound with `+ Bar`
-        //
-        //    Suggestion:
-        //      fn foo<T>(t: T) where T: Foo { ... }
-        //                            ^^
-        //                            |
-        //                            replace with: `T: Bar +`
-        //
-        //
-        // 3) When the type parameter has been provided many bounds
-        //
-        //    Message:
-        //      fn foo<T>(t: T) where T: Foo, T: Bar {... }
-        //             - help: consider further restricting this type parameter with `where T: Zar`
-        //
-        //    Suggestion:
-        //      fn foo<T>(t: T) where T: Foo, T: Bar {... }
-        //                                          - insert: `, T: Zar`
-        //
-        // Additionally, there may be no `where` clause whatsoever in the case that this was
-        // reached because the generic parameter has a default:
-        //
-        //    Message:
-        //      trait Foo<T=()> {... }
-        //             - help: consider further restricting this type parameter with `where T: Zar`
-        //
-        //    Suggestion:
-        //      trait Foo<T=()> where T: Zar {... }
-        //                     - insert: `where T: Zar`
-
-        if matches!(param.kind, hir::GenericParamKind::Type { default: Some(_), .. })
-            && generics.where_clause.predicates.len() == 0
+        if generics.where_clause.predicates.is_empty()
+        // Given `trait Base<T = String>: Super<T>` where `T: Copy`, suggest restricting in the
+        // `where` clause instead of `trait Base<T: Copy = String>: Super<T>`.
+        && !matches!(param.kind, hir::GenericParamKind::Type { default: Some(_), .. })
         {
-            // Suggest a bound, but there is no existing `where` clause *and* the type param has a
-            // default (`<T=Foo>`), so we suggest adding `where T: Bar`.
-            err.span_suggestion_verbose(
-                generics.where_clause.tail_span_for_suggestion(),
-                &msg_restrict_type_further,
-                format!(" where {}: {}", param_name, constraint),
-                Applicability::MachineApplicable,
-            );
+            if let Some(span) = param.bounds_span_for_suggestions() {
+                // If user has provided some bounds, suggest restricting them:
+                //
+                //   fn foo<T: Foo>(t: T) { ... }
+                //             ---
+                //             |
+                //             help: consider further restricting this bound with `+ Bar`
+                //
+                // Suggestion for tools in this case is:
+                //
+                //   fn foo<T: Foo>(t: T) { ... }
+                //          --
+                //          |
+                //          replace with: `T: Bar +`
+                suggest_restrict(span);
+            } else {
+                // If user hasn't provided any bounds, suggest adding a new one:
+                //
+                //   fn foo<T>(t: T) { ... }
+                //          - help: consider restricting this type parameter with `T: Foo`
+                suggestions.push((
+                    param.span.shrink_to_hi(),
+                    format!(": {}", constraint),
+                    SuggestChangingConstraintsMessage::RestrictType { ty: param_name },
+                ));
+            }
         } else {
-            let mut param_spans = Vec::new();
+            // This part is a bit tricky, because using the `where` clause user can
+            // provide zero, one or many bounds for the same type parameter, so we
+            // have following cases to consider:
+            //
+            // 1) When the type parameter has been provided zero bounds
+            //
+            //    Message:
+            //      fn foo<X, Y>(x: X, y: Y) where Y: Foo { ... }
+            //             - help: consider restricting this type parameter with `where X: Bar`
+            //
+            //    Suggestion:
+            //      fn foo<X, Y>(x: X, y: Y) where Y: Foo { ... }
+            //                                           - insert: `, X: Bar`
+            //
+            //
+            // 2) When the type parameter has been provided one bound
+            //
+            //    Message:
+            //      fn foo<T>(t: T) where T: Foo { ... }
+            //                            ^^^^^^
+            //                            |
+            //                            help: consider further restricting this bound with `+ Bar`
+            //
+            //    Suggestion:
+            //      fn foo<T>(t: T) where T: Foo { ... }
+            //                            ^^
+            //                            |
+            //                            replace with: `T: Bar +`
+            //
+            //
+            // 3) When the type parameter has been provided many bounds
+            //
+            //    Message:
+            //      fn foo<T>(t: T) where T: Foo, T: Bar {... }
+            //             - help: consider further restricting this type parameter with `where T: Zar`
+            //
+            //    Suggestion:
+            //      fn foo<T>(t: T) where T: Foo, T: Bar {... }
+            //                                          - insert: `, T: Zar`
+            //
+            // Additionally, there may be no `where` clause whatsoever in the case that this was
+            // reached because the generic parameter has a default:
+            //
+            //    Message:
+            //      trait Foo<T=()> {... }
+            //             - help: consider further restricting this type parameter with `where T: Zar`
+            //
+            //    Suggestion:
+            //      trait Foo<T=()> where T: Zar {... }
+            //                     - insert: `where T: Zar`
 
-            for predicate in generics.where_clause.predicates {
-                if let WherePredicate::BoundPredicate(WhereBoundPredicate {
-                    span,
-                    bounded_ty,
-                    ..
-                }) = predicate
-                {
-                    if let TyKind::Path(QPath::Resolved(_, path)) = &bounded_ty.kind {
-                        if let Some(segment) = path.segments.first() {
-                            if segment.ident.to_string() == param_name {
-                                param_spans.push(span);
+            if matches!(param.kind, hir::GenericParamKind::Type { default: Some(_), .. })
+                && generics.where_clause.predicates.len() == 0
+            {
+                // Suggest a bound, but there is no existing `where` clause *and* the type param has a
+                // default (`<T=Foo>`), so we suggest adding `where T: Bar`.
+                suggestions.push((
+                    generics.where_clause.tail_span_for_suggestion(),
+                    format!(" where {}: {}", param_name, constraint),
+                    SuggestChangingConstraintsMessage::RestrictTypeFurther { ty: param_name },
+                ));
+            } else {
+                let mut param_spans = Vec::new();
+
+                for predicate in generics.where_clause.predicates {
+                    if let WherePredicate::BoundPredicate(WhereBoundPredicate {
+                        span,
+                        bounded_ty,
+                        ..
+                    }) = predicate
+                    {
+                        if let TyKind::Path(QPath::Resolved(_, path)) = &bounded_ty.kind {
+                            if let Some(segment) = path.segments.first() {
+                                if segment.ident.to_string() == param_name {
+                                    param_spans.push(span);
+                                }
                             }
                         }
                     }
                 }
-            }
 
-            match param_spans[..] {
-                [&param_span] => suggest_restrict(param_span.shrink_to_hi()),
-                _ => {
-                    err.span_suggestion_verbose(
-                        generics.where_clause.tail_span_for_suggestion(),
-                        &msg_restrict_type_further,
-                        format!(", {}: {}", param_name, constraint),
-                        Applicability::MachineApplicable,
-                    );
+                match param_spans[..] {
+                    [&param_span] => suggest_restrict(param_span.shrink_to_hi()),
+                    _ => {
+                        suggestions.push((
+                            generics.where_clause.tail_span_for_suggestion(),
+                            constraints
+                                .iter()
+                                .map(|&(constraint, _)| format!(", {}: {}", param_name, constraint))
+                                .collect::<String>(),
+                            SuggestChangingConstraintsMessage::RestrictTypeFurther {
+                                ty: param_name,
+                            },
+                        ));
+                    }
                 }
             }
         }
+    }
 
-        true
+    if suggestions.len() == 1 {
+        let (span, suggestion, msg) = suggestions.pop().unwrap();
+
+        let s;
+        let msg = match msg {
+            SuggestChangingConstraintsMessage::RestrictBoundFurther => {
+                "consider further restricting this bound"
+            }
+            SuggestChangingConstraintsMessage::RestrictType { ty } => {
+                s = format!("consider restricting type parameter `{}`", ty);
+                &s
+            }
+            SuggestChangingConstraintsMessage::RestrictTypeFurther { ty } => {
+                s = format!("consider further restricting type parameter `{}`", ty);
+                &s
+            }
+            SuggestChangingConstraintsMessage::RemovingQSized => {
+                "consider removing the `?Sized` bound to make the type parameter `Sized`"
+            }
+        };
+
+        err.span_suggestion_verbose(span, msg, suggestion, applicability);
+    } else {
+        err.multipart_suggestion_verbose(
+            "consider restricting type parameters",
+            suggestions.into_iter().map(|(span, suggestion, _)| (span, suggestion)).collect(),
+            applicability,
+        );
     }
+
+    true
 }
 
 /// Collect al types that have an implicit `'static` obligation that we could suggest `'_` for.
diff --git a/compiler/rustc_mir_transform/src/const_prop.rs b/compiler/rustc_mir_transform/src/const_prop.rs
index c5ef1e101460f..d849bc408fab4 100644
--- a/compiler/rustc_mir_transform/src/const_prop.rs
+++ b/compiler/rustc_mir_transform/src/const_prop.rs
@@ -1196,12 +1196,21 @@ impl<'tcx> MutVisitor<'tcx> for ConstPropagator<'_, 'tcx> {
                             AssertKind::RemainderByZero(op) => {
                                 Some(AssertKind::RemainderByZero(eval_to_int(op)))
                             }
+                            AssertKind::Overflow(bin_op @ (BinOp::Div | BinOp::Rem), op1, op2) => {
+                                // Division overflow is *UB* in the MIR, and different than the
+                                // other overflow checks.
+                                Some(AssertKind::Overflow(
+                                    *bin_op,
+                                    eval_to_int(op1),
+                                    eval_to_int(op2),
+                                ))
+                            }
                             AssertKind::BoundsCheck { ref len, ref index } => {
                                 let len = eval_to_int(len);
                                 let index = eval_to_int(index);
                                 Some(AssertKind::BoundsCheck { len, index })
                             }
-                            // Overflow is are already covered by checks on the binary operators.
+                            // Remaining overflow errors are already covered by checks on the binary operators.
                             AssertKind::Overflow(..) | AssertKind::OverflowNeg(_) => None,
                             // Need proper const propagator for these.
                             _ => None,
diff --git a/compiler/rustc_session/Cargo.toml b/compiler/rustc_session/Cargo.toml
index 37cfc4a0dc3c2..6b1eaa4d399d9 100644
--- a/compiler/rustc_session/Cargo.toml
+++ b/compiler/rustc_session/Cargo.toml
@@ -15,6 +15,5 @@ rustc_serialize = { path = "../rustc_serialize" }
 rustc_data_structures = { path = "../rustc_data_structures" }
 rustc_span = { path = "../rustc_span" }
 rustc_fs_util = { path = "../rustc_fs_util" }
-num_cpus = "1.0"
 rustc_ast = { path = "../rustc_ast" }
 rustc_lint_defs = { path = "../rustc_lint_defs" }
diff --git a/compiler/rustc_session/src/options.rs b/compiler/rustc_session/src/options.rs
index c2b13346cd6c9..43123d30ad5c6 100644
--- a/compiler/rustc_session/src/options.rs
+++ b/compiler/rustc_session/src/options.rs
@@ -551,7 +551,7 @@ mod parse {
     crate fn parse_threads(slot: &mut usize, v: Option<&str>) -> bool {
         match v.and_then(|s| s.parse().ok()) {
             Some(0) => {
-                *slot = ::num_cpus::get();
+                *slot = std::thread::available_parallelism().map_or(1, std::num::NonZeroUsize::get);
                 true
             }
             Some(i) => {
diff --git a/compiler/rustc_typeck/src/check/demand.rs b/compiler/rustc_typeck/src/check/demand.rs
index 040a087b2352e..f01843ebabacf 100644
--- a/compiler/rustc_typeck/src/check/demand.rs
+++ b/compiler/rustc_typeck/src/check/demand.rs
@@ -276,11 +276,28 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             // we suggest adding a separate return expression instead.
             // (To avoid things like suggesting `Ok(while .. { .. })`.)
             if expr_ty.is_unit() {
+                let mut id = expr.hir_id;
+                let mut parent;
+
+                // Unroll desugaring, to make sure this works for `for` loops etc.
+                loop {
+                    parent = self.tcx.hir().get_parent_node(id);
+                    if let Some(parent_span) = self.tcx.hir().opt_span(parent) {
+                        if parent_span.find_ancestor_inside(expr.span).is_some() {
+                            // The parent node is part of the same span, so is the result of the
+                            // same expansion/desugaring and not the 'real' parent node.
+                            id = parent;
+                            continue;
+                        }
+                    }
+                    break;
+                }
+
                 if let Some(hir::Node::Block(&hir::Block {
                     span: block_span, expr: Some(e), ..
-                })) = self.tcx.hir().find(self.tcx.hir().get_parent_node(expr.hir_id))
+                })) = self.tcx.hir().find(parent)
                 {
-                    if e.hir_id == expr.hir_id {
+                    if e.hir_id == id {
                         if let Some(span) = expr.span.find_ancestor_inside(block_span) {
                             let return_suggestions =
                                 if self.tcx.is_diagnostic_item(sym::Result, expected_adt.did) {
diff --git a/library/core/src/ffi/mod.rs b/library/core/src/ffi/mod.rs
index e5255686ff984..2b611e5aae276 100644
--- a/library/core/src/ffi/mod.rs
+++ b/library/core/src/ffi/mod.rs
@@ -117,7 +117,7 @@ mod c_char_definition {
             all(target_os = "android", any(target_arch = "aarch64", target_arch = "arm")),
             all(target_os = "l4re", target_arch = "x86_64"),
             all(
-                target_os = "freebsd",
+                any(target_os = "freebsd", target_os = "openbsd"),
                 any(
                     target_arch = "aarch64",
                     target_arch = "arm",
@@ -130,7 +130,6 @@ mod c_char_definition {
                 target_os = "netbsd",
                 any(target_arch = "aarch64", target_arch = "arm", target_arch = "powerpc")
             ),
-            all(target_os = "openbsd", target_arch = "aarch64"),
             all(
                 target_os = "vxworks",
                 any(
diff --git a/library/core/tests/num/wrapping.rs b/library/core/tests/num/wrapping.rs
index c4fb321ef26cf..8ded139a1809f 100644
--- a/library/core/tests/num/wrapping.rs
+++ b/library/core/tests/num/wrapping.rs
@@ -308,3 +308,13 @@ fn wrapping_int_api() {
         }
     }
 }
+
+#[test]
+fn wrapping_const() {
+    // Specifically the wrapping behavior of division and remainder is subtle,
+    // see https://github.com/rust-lang/rust/pull/94512.
+    const _: () = {
+        assert!(i32::MIN.wrapping_div(-1) == i32::MIN);
+        assert!(i32::MIN.wrapping_rem(-1) == 0);
+    };
+}
diff --git a/library/portable-simd/crates/core_simd/src/intrinsics.rs b/library/portable-simd/crates/core_simd/src/intrinsics.rs
index 4c68d11e8932a..cf2c0a02351ed 100644
--- a/library/portable-simd/crates/core_simd/src/intrinsics.rs
+++ b/library/portable-simd/crates/core_simd/src/intrinsics.rs
@@ -18,9 +18,10 @@
 //!
 //! Unless stated otherwise, all intrinsics for binary operations require SIMD vectors of equal types and lengths.
 
-/// These intrinsics aren't linked directly from LLVM and are mostly undocumented, however they are
-/// mostly lowered to the matching LLVM instructions by the compiler in a fairly straightforward manner.
-/// The associated LLVM instruction or intrinsic is documented alongside each Rust intrinsic function.
+
+// These intrinsics aren't linked directly from LLVM and are mostly undocumented, however they are
+// mostly lowered to the matching LLVM instructions by the compiler in a fairly straightforward manner.
+// The associated LLVM instruction or intrinsic is documented alongside each Rust intrinsic function.
 extern "platform-intrinsic" {
     /// add/fadd
     pub(crate) fn simd_add<T>(x: T, y: T) -> T;
diff --git a/library/std/src/os/fd/mod.rs b/library/std/src/os/fd/mod.rs
index df11dc21aa7a6..13bb079194fbe 100644
--- a/library/std/src/os/fd/mod.rs
+++ b/library/std/src/os/fd/mod.rs
@@ -11,3 +11,6 @@ pub mod owned;
 
 // Implementations for `AsRawFd` etc. for network types.
 mod net;
+
+#[cfg(test)]
+mod tests;
diff --git a/library/std/src/os/fd/owned.rs b/library/std/src/os/fd/owned.rs
index d72f9a2ff9c8f..807b057234ac1 100644
--- a/library/std/src/os/fd/owned.rs
+++ b/library/std/src/os/fd/owned.rs
@@ -21,6 +21,10 @@ use crate::sys_common::{AsInner, FromInner, IntoInner};
 /// descriptor, so it can be used in FFI in places where a file descriptor is
 /// passed as an argument, it is not captured or consumed, and it never has the
 /// value `-1`.
+///
+/// This type's `.to_owned()` implementation returns another `BorrowedFd`
+/// rather than an `OwnedFd`. It just makes a trivial copy of the raw file
+/// descriptor, which is then borrowed under the same lifetime.
 #[derive(Copy, Clone)]
 #[repr(transparent)]
 #[rustc_layout_scalar_valid_range_start(0)]
@@ -62,7 +66,7 @@ impl BorrowedFd<'_> {
     /// the returned `BorrowedFd`, and it must not have the value `-1`.
     #[inline]
     #[unstable(feature = "io_safety", issue = "87074")]
-    pub unsafe fn borrow_raw_fd(fd: RawFd) -> Self {
+    pub unsafe fn borrow_raw(fd: RawFd) -> Self {
         assert_ne!(fd, u32::MAX as RawFd);
         // SAFETY: we just asserted that the value is in the valid range and isn't `-1` (the only value bigger than `0xFF_FF_FF_FE` unsigned)
         unsafe { Self { fd, _phantom: PhantomData } }
@@ -231,7 +235,7 @@ impl AsFd for OwnedFd {
         // Safety: `OwnedFd` and `BorrowedFd` have the same validity
         // invariants, and the `BorrowdFd` is bounded by the lifetime
         // of `&self`.
-        unsafe { BorrowedFd::borrow_raw_fd(self.as_raw_fd()) }
+        unsafe { BorrowedFd::borrow_raw(self.as_raw_fd()) }
     }
 }
 
diff --git a/library/std/src/os/fd/tests.rs b/library/std/src/os/fd/tests.rs
new file mode 100644
index 0000000000000..26ef93e3d7110
--- /dev/null
+++ b/library/std/src/os/fd/tests.rs
@@ -0,0 +1,34 @@
+#[cfg(any(unix, target_os = "wasi"))]
+#[test]
+fn test_raw_fd() {
+    #[cfg(unix)]
+    use crate::os::unix::io::{AsRawFd, BorrowedFd, FromRawFd, IntoRawFd, RawFd};
+    #[cfg(target_os = "wasi")]
+    use crate::os::wasi::io::{AsRawFd, BorrowedFd, FromRawFd, IntoRawFd, RawFd};
+
+    let raw_fd: RawFd = crate::io::stdin().as_raw_fd();
+
+    let stdin_as_file = unsafe { crate::fs::File::from_raw_fd(raw_fd) };
+    assert_eq!(stdin_as_file.as_raw_fd(), raw_fd);
+    assert_eq!(unsafe { BorrowedFd::borrow_raw(raw_fd).as_raw_fd() }, raw_fd);
+    assert_eq!(stdin_as_file.into_raw_fd(), 0);
+}
+
+#[cfg(any(unix, target_os = "wasi"))]
+#[test]
+fn test_fd() {
+    #[cfg(unix)]
+    use crate::os::unix::io::{AsFd, AsRawFd, BorrowedFd, FromRawFd, IntoRawFd, OwnedFd, RawFd};
+    #[cfg(target_os = "wasi")]
+    use crate::os::wasi::io::{AsFd, AsRawFd, BorrowedFd, FromRawFd, IntoRawFd, OwnedFd, RawFd};
+
+    let stdin = crate::io::stdin();
+    let fd: BorrowedFd<'_> = stdin.as_fd();
+    let raw_fd: RawFd = fd.as_raw_fd();
+    let owned_fd: OwnedFd = unsafe { OwnedFd::from_raw_fd(raw_fd) };
+
+    let stdin_as_file = crate::fs::File::from(owned_fd);
+
+    assert_eq!(stdin_as_file.as_fd().as_raw_fd(), raw_fd);
+    assert_eq!(Into::<OwnedFd>::into(stdin_as_file).into_raw_fd(), raw_fd);
+}
diff --git a/library/std/src/os/windows/io/handle.rs b/library/std/src/os/windows/io/handle.rs
index 8df6c54a4144e..842a15ae1bfc0 100644
--- a/library/std/src/os/windows/io/handle.rs
+++ b/library/std/src/os/windows/io/handle.rs
@@ -28,6 +28,10 @@ use crate::sys_common::{AsInner, FromInner, IntoInner};
 /// And, it *may* have the value `NULL` (0), which can occur when consoles are
 /// detached from processes, or when `windows_subsystem` is used.
 ///
+/// This type's `.to_owned()` implementation returns another `BorrowedHandle`
+/// rather than an `OwnedHandle`. It just makes a trivial copy of the raw
+/// handle, which is then borrowed under the same lifetime.
+///
 /// [here]: https://devblogs.microsoft.com/oldnewthing/20040302-00/?p=40443
 #[derive(Copy, Clone)]
 #[repr(transparent)]
@@ -131,7 +135,7 @@ impl BorrowedHandle<'_> {
     /// [here]: https://devblogs.microsoft.com/oldnewthing/20040302-00/?p=40443
     #[inline]
     #[unstable(feature = "io_safety", issue = "87074")]
-    pub unsafe fn borrow_raw_handle(handle: RawHandle) -> Self {
+    pub unsafe fn borrow_raw(handle: RawHandle) -> Self {
         Self { handle, _phantom: PhantomData }
     }
 }
@@ -345,7 +349,7 @@ impl AsHandle for OwnedHandle {
         // Safety: `OwnedHandle` and `BorrowedHandle` have the same validity
         // invariants, and the `BorrowdHandle` is bounded by the lifetime
         // of `&self`.
-        unsafe { BorrowedHandle::borrow_raw_handle(self.as_raw_handle()) }
+        unsafe { BorrowedHandle::borrow_raw(self.as_raw_handle()) }
     }
 }
 
@@ -373,49 +377,49 @@ impl From<OwnedHandle> for fs::File {
 impl AsHandle for crate::io::Stdin {
     #[inline]
     fn as_handle(&self) -> BorrowedHandle<'_> {
-        unsafe { BorrowedHandle::borrow_raw_handle(self.as_raw_handle()) }
+        unsafe { BorrowedHandle::borrow_raw(self.as_raw_handle()) }
     }
 }
 
 impl<'a> AsHandle for crate::io::StdinLock<'a> {
     #[inline]
     fn as_handle(&self) -> BorrowedHandle<'_> {
-        unsafe { BorrowedHandle::borrow_raw_handle(self.as_raw_handle()) }
+        unsafe { BorrowedHandle::borrow_raw(self.as_raw_handle()) }
     }
 }
 
 impl AsHandle for crate::io::Stdout {
     #[inline]
     fn as_handle(&self) -> BorrowedHandle<'_> {
-        unsafe { BorrowedHandle::borrow_raw_handle(self.as_raw_handle()) }
+        unsafe { BorrowedHandle::borrow_raw(self.as_raw_handle()) }
     }
 }
 
 impl<'a> AsHandle for crate::io::StdoutLock<'a> {
     #[inline]
     fn as_handle(&self) -> BorrowedHandle<'_> {
-        unsafe { BorrowedHandle::borrow_raw_handle(self.as_raw_handle()) }
+        unsafe { BorrowedHandle::borrow_raw(self.as_raw_handle()) }
     }
 }
 
 impl AsHandle for crate::io::Stderr {
     #[inline]
     fn as_handle(&self) -> BorrowedHandle<'_> {
-        unsafe { BorrowedHandle::borrow_raw_handle(self.as_raw_handle()) }
+        unsafe { BorrowedHandle::borrow_raw(self.as_raw_handle()) }
     }
 }
 
 impl<'a> AsHandle for crate::io::StderrLock<'a> {
     #[inline]
     fn as_handle(&self) -> BorrowedHandle<'_> {
-        unsafe { BorrowedHandle::borrow_raw_handle(self.as_raw_handle()) }
+        unsafe { BorrowedHandle::borrow_raw(self.as_raw_handle()) }
     }
 }
 
 impl AsHandle for crate::process::ChildStdin {
     #[inline]
     fn as_handle(&self) -> BorrowedHandle<'_> {
-        unsafe { BorrowedHandle::borrow_raw_handle(self.as_raw_handle()) }
+        unsafe { BorrowedHandle::borrow_raw(self.as_raw_handle()) }
     }
 }
 
@@ -429,7 +433,7 @@ impl From<crate::process::ChildStdin> for OwnedHandle {
 impl AsHandle for crate::process::ChildStdout {
     #[inline]
     fn as_handle(&self) -> BorrowedHandle<'_> {
-        unsafe { BorrowedHandle::borrow_raw_handle(self.as_raw_handle()) }
+        unsafe { BorrowedHandle::borrow_raw(self.as_raw_handle()) }
     }
 }
 
@@ -443,7 +447,7 @@ impl From<crate::process::ChildStdout> for OwnedHandle {
 impl AsHandle for crate::process::ChildStderr {
     #[inline]
     fn as_handle(&self) -> BorrowedHandle<'_> {
-        unsafe { BorrowedHandle::borrow_raw_handle(self.as_raw_handle()) }
+        unsafe { BorrowedHandle::borrow_raw(self.as_raw_handle()) }
     }
 }
 
@@ -457,7 +461,7 @@ impl From<crate::process::ChildStderr> for OwnedHandle {
 impl<T> AsHandle for crate::thread::JoinHandle<T> {
     #[inline]
     fn as_handle(&self) -> BorrowedHandle<'_> {
-        unsafe { BorrowedHandle::borrow_raw_handle(self.as_raw_handle()) }
+        unsafe { BorrowedHandle::borrow_raw(self.as_raw_handle()) }
     }
 }
 
diff --git a/library/std/src/os/windows/io/socket.rs b/library/std/src/os/windows/io/socket.rs
index 2f13eb77a1b94..a695a4106e810 100644
--- a/library/std/src/os/windows/io/socket.rs
+++ b/library/std/src/os/windows/io/socket.rs
@@ -21,6 +21,10 @@ use crate::sys::cvt;
 /// so it can be used in FFI in places where a socket is passed as an argument,
 /// it is not captured or consumed, and it never has the value
 /// `INVALID_SOCKET`.
+///
+/// This type's `.to_owned()` implementation returns another `BorrowedSocket`
+/// rather than an `OwnedSocket`. It just makes a trivial copy of the raw
+/// socket, which is then borrowed under the same lifetime.
 #[derive(Copy, Clone)]
 #[repr(transparent)]
 #[rustc_layout_scalar_valid_range_start(0)]
@@ -67,7 +71,7 @@ impl BorrowedSocket<'_> {
     /// `INVALID_SOCKET`.
     #[inline]
     #[unstable(feature = "io_safety", issue = "87074")]
-    pub unsafe fn borrow_raw_socket(socket: RawSocket) -> Self {
+    pub unsafe fn borrow_raw(socket: RawSocket) -> Self {
         debug_assert_ne!(socket, c::INVALID_SOCKET as RawSocket);
         Self { socket, _phantom: PhantomData }
     }
@@ -239,14 +243,14 @@ impl AsSocket for OwnedSocket {
         // Safety: `OwnedSocket` and `BorrowedSocket` have the same validity
         // invariants, and the `BorrowdSocket` is bounded by the lifetime
         // of `&self`.
-        unsafe { BorrowedSocket::borrow_raw_socket(self.as_raw_socket()) }
+        unsafe { BorrowedSocket::borrow_raw(self.as_raw_socket()) }
     }
 }
 
 impl AsSocket for crate::net::TcpStream {
     #[inline]
     fn as_socket(&self) -> BorrowedSocket<'_> {
-        unsafe { BorrowedSocket::borrow_raw_socket(self.as_raw_socket()) }
+        unsafe { BorrowedSocket::borrow_raw(self.as_raw_socket()) }
     }
 }
 
@@ -267,7 +271,7 @@ impl From<OwnedSocket> for crate::net::TcpStream {
 impl AsSocket for crate::net::TcpListener {
     #[inline]
     fn as_socket(&self) -> BorrowedSocket<'_> {
-        unsafe { BorrowedSocket::borrow_raw_socket(self.as_raw_socket()) }
+        unsafe { BorrowedSocket::borrow_raw(self.as_raw_socket()) }
     }
 }
 
@@ -288,7 +292,7 @@ impl From<OwnedSocket> for crate::net::TcpListener {
 impl AsSocket for crate::net::UdpSocket {
     #[inline]
     fn as_socket(&self) -> BorrowedSocket<'_> {
-        unsafe { BorrowedSocket::borrow_raw_socket(self.as_raw_socket()) }
+        unsafe { BorrowedSocket::borrow_raw(self.as_raw_socket()) }
     }
 }
 
diff --git a/library/std/src/sys/unix/stdio.rs b/library/std/src/sys/unix/stdio.rs
index b359987595d30..e4d83ba0ffd13 100644
--- a/library/std/src/sys/unix/stdio.rs
+++ b/library/std/src/sys/unix/stdio.rs
@@ -96,7 +96,7 @@ pub fn panic_output() -> Option<impl io::Write> {
 impl AsFd for io::Stdin {
     #[inline]
     fn as_fd(&self) -> BorrowedFd<'_> {
-        unsafe { BorrowedFd::borrow_raw_fd(libc::STDIN_FILENO) }
+        unsafe { BorrowedFd::borrow_raw(libc::STDIN_FILENO) }
     }
 }
 
@@ -104,7 +104,7 @@ impl AsFd for io::Stdin {
 impl<'a> AsFd for io::StdinLock<'a> {
     #[inline]
     fn as_fd(&self) -> BorrowedFd<'_> {
-        unsafe { BorrowedFd::borrow_raw_fd(libc::STDIN_FILENO) }
+        unsafe { BorrowedFd::borrow_raw(libc::STDIN_FILENO) }
     }
 }
 
@@ -112,7 +112,7 @@ impl<'a> AsFd for io::StdinLock<'a> {
 impl AsFd for io::Stdout {
     #[inline]
     fn as_fd(&self) -> BorrowedFd<'_> {
-        unsafe { BorrowedFd::borrow_raw_fd(libc::STDOUT_FILENO) }
+        unsafe { BorrowedFd::borrow_raw(libc::STDOUT_FILENO) }
     }
 }
 
@@ -120,7 +120,7 @@ impl AsFd for io::Stdout {
 impl<'a> AsFd for io::StdoutLock<'a> {
     #[inline]
     fn as_fd(&self) -> BorrowedFd<'_> {
-        unsafe { BorrowedFd::borrow_raw_fd(libc::STDOUT_FILENO) }
+        unsafe { BorrowedFd::borrow_raw(libc::STDOUT_FILENO) }
     }
 }
 
@@ -128,7 +128,7 @@ impl<'a> AsFd for io::StdoutLock<'a> {
 impl AsFd for io::Stderr {
     #[inline]
     fn as_fd(&self) -> BorrowedFd<'_> {
-        unsafe { BorrowedFd::borrow_raw_fd(libc::STDERR_FILENO) }
+        unsafe { BorrowedFd::borrow_raw(libc::STDERR_FILENO) }
     }
 }
 
@@ -136,6 +136,6 @@ impl AsFd for io::Stderr {
 impl<'a> AsFd for io::StderrLock<'a> {
     #[inline]
     fn as_fd(&self) -> BorrowedFd<'_> {
-        unsafe { BorrowedFd::borrow_raw_fd(libc::STDERR_FILENO) }
+        unsafe { BorrowedFd::borrow_raw(libc::STDERR_FILENO) }
     }
 }
diff --git a/library/stdarch b/library/stdarch
index b4a0e07552cf9..bcbe010614f39 160000
--- a/library/stdarch
+++ b/library/stdarch
@@ -1 +1 @@
-Subproject commit b4a0e07552cf90ef8f1a5b775bf70e4db94b3d63
+Subproject commit bcbe010614f398ec86f3a9274d22e33e5f2ee60b
diff --git a/src/bootstrap/Cargo.toml b/src/bootstrap/Cargo.toml
index 592a137e379de..02efc08cc791f 100644
--- a/src/bootstrap/Cargo.toml
+++ b/src/bootstrap/Cargo.toml
@@ -37,7 +37,6 @@ test = false
 build_helper = { path = "../build_helper" }
 cmake = "0.1.38"
 filetime = "0.2"
-num_cpus = "1.0"
 getopts = "0.2.19"
 cc = "1.0.69"
 libc = "0.2"
diff --git a/src/bootstrap/config.rs b/src/bootstrap/config.rs
index d6f77fe6cd6d0..ce76ccd57551d 100644
--- a/src/bootstrap/config.rs
+++ b/src/bootstrap/config.rs
@@ -1187,7 +1187,7 @@ fn set<T>(field: &mut T, val: Option<T>) {
 
 fn threads_from_config(v: u32) -> u32 {
     match v {
-        0 => num_cpus::get() as u32,
+        0 => std::thread::available_parallelism().map_or(1, std::num::NonZeroUsize::get) as u32,
         n => n,
     }
 }
diff --git a/src/bootstrap/flags.rs b/src/bootstrap/flags.rs
index 9180c5f03af68..74528f2752f5f 100644
--- a/src/bootstrap/flags.rs
+++ b/src/bootstrap/flags.rs
@@ -208,7 +208,7 @@ To learn more about a subcommand, run `./x.py <subcommand> -h`",
         let j_msg = format!(
             "number of jobs to run in parallel; \
              defaults to {} (this host's logical CPU count)",
-            num_cpus::get()
+            std::thread::available_parallelism().map_or(1, std::num::NonZeroUsize::get)
         );
         opts.optopt("j", "jobs", &j_msg, "JOBS");
         opts.optflag("h", "help", "print this help message");
diff --git a/src/bootstrap/lib.rs b/src/bootstrap/lib.rs
index 86339c8d7f88d..6a58de40181c2 100644
--- a/src/bootstrap/lib.rs
+++ b/src/bootstrap/lib.rs
@@ -917,7 +917,9 @@ impl Build {
     /// Returns the number of parallel jobs that have been configured for this
     /// build.
     fn jobs(&self) -> u32 {
-        self.config.jobs.unwrap_or_else(|| num_cpus::get() as u32)
+        self.config.jobs.unwrap_or_else(|| {
+            std::thread::available_parallelism().map_or(1, std::num::NonZeroUsize::get) as u32
+        })
     }
 
     fn debuginfo_map_to(&self, which: GitRepo) -> Option<String> {
diff --git a/src/doc/rustc/src/platform-support.md b/src/doc/rustc/src/platform-support.md
index d7e0b9d50f084..4c05818440b09 100644
--- a/src/doc/rustc/src/platform-support.md
+++ b/src/doc/rustc/src/platform-support.md
@@ -139,7 +139,7 @@ target | std | notes
 `armv7r-none-eabi` | * | Bare ARMv7-R
 `armv7r-none-eabihf` | * | Bare ARMv7-R, hardfloat
 `asmjs-unknown-emscripten` | ✓ | asm.js via Emscripten
-`i586-pc-windows-msvc` | ✓ | 32-bit Windows w/o SSE
+`i586-pc-windows-msvc` | * | 32-bit Windows w/o SSE
 `i586-unknown-linux-gnu` | ✓ | 32-bit Linux w/o SSE (kernel 4.4, glibc 2.23)
 `i586-unknown-linux-musl` | ✓ | 32-bit Linux w/o SSE, MUSL
 `i686-linux-android` | ✓ | 32-bit x86 Android
@@ -236,7 +236,7 @@ target | std | host | notes
 `hexagon-unknown-linux-musl` | ? |  |
 `i386-apple-ios` | ✓ |  | 32-bit x86 iOS
 `i686-apple-darwin` | ✓ | ✓ | 32-bit macOS (10.7+, Lion+)
-`i686-pc-windows-msvc` | ✓ |  | 32-bit Windows XP support
+`i686-pc-windows-msvc` | * |  | 32-bit Windows XP support
 `i686-unknown-haiku` | ✓ | ✓ | 32-bit Haiku
 `i686-unknown-netbsd` | ✓ | ✓ | NetBSD/i386 with SSE2
 [`i686-unknown-openbsd`](platform-support/openbsd.md) | ✓ | ✓ | 32-bit OpenBSD
@@ -283,7 +283,7 @@ target | std | host | notes
 [`wasm64-unknown-unknown`](platform-support/wasm64-unknown-unknown.md) | ? |  | WebAssembly
 `x86_64-apple-ios-macabi` | ✓ |  | Apple Catalyst on x86_64
 `x86_64-apple-tvos` | * | | x86 64-bit tvOS
-`x86_64-pc-windows-msvc` | ✓ |  | 64-bit Windows XP support
+`x86_64-pc-windows-msvc` | * |  | 64-bit Windows XP support
 `x86_64-sun-solaris` | ? |  | Deprecated target for 64-bit Solaris 10/11, illumos
 `x86_64-unknown-dragonfly` | ✓ | ✓ | 64-bit DragonFlyBSD
 `x86_64-unknown-haiku` | ✓ | ✓ | 64-bit Haiku
diff --git a/src/test/ui/async-await/proper-span-for-type-error.fixed b/src/test/ui/async-await/proper-span-for-type-error.fixed
index 1f1e1184dcc02..7d43b575d2f66 100644
--- a/src/test/ui/async-await/proper-span-for-type-error.fixed
+++ b/src/test/ui/async-await/proper-span-for-type-error.fixed
@@ -5,7 +5,8 @@
 async fn a() {}
 
 async fn foo() -> Result<(), i32> {
-    Ok(a().await) //~ ERROR mismatched types
+    a().await;
+    Ok(()) //~ ERROR mismatched types
 }
 
 fn main() {}
diff --git a/src/test/ui/async-await/proper-span-for-type-error.stderr b/src/test/ui/async-await/proper-span-for-type-error.stderr
index 611dc0407bf96..25f05156ce2bc 100644
--- a/src/test/ui/async-await/proper-span-for-type-error.stderr
+++ b/src/test/ui/async-await/proper-span-for-type-error.stderr
@@ -6,10 +6,11 @@ LL |     a().await
    |
    = note:   expected enum `Result<(), i32>`
            found unit type `()`
-help: try wrapping the expression in `Ok`
+help: try adding an expression at the end of the block
+   |
+LL ~     a().await;
+LL ~     Ok(())
    |
-LL |     Ok(a().await)
-   |     +++         +
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/consts/const-int-unchecked.stderr b/src/test/ui/consts/const-int-unchecked.stderr
index 22e8c8dabc970..ad880d56d904d 100644
--- a/src/test/ui/consts/const-int-unchecked.stderr
+++ b/src/test/ui/consts/const-int-unchecked.stderr
@@ -266,7 +266,7 @@ error[E0080]: evaluation of constant value failed
   --> $DIR/const-int-unchecked.rs:134:25
    |
 LL | const _: i32 = unsafe { std::intrinsics::unchecked_div(i32::MIN, -1) };
-   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ overflow executing `unchecked_div`
+   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ overflow in signed division (dividing MIN by -1)
 
 error[E0080]: evaluation of constant value failed
   --> $DIR/const-int-unchecked.rs:137:25
@@ -278,7 +278,7 @@ error[E0080]: evaluation of constant value failed
   --> $DIR/const-int-unchecked.rs:139:25
    |
 LL | const _: i32 = unsafe { std::intrinsics::unchecked_rem(i32::MIN, -1) };
-   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ overflow executing `unchecked_rem`
+   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ overflow in signed remainder (dividing MIN by -1)
 
 error[E0080]: evaluation of constant value failed
   --> $DIR/const-int-unchecked.rs:144:25
diff --git a/src/test/ui/did_you_mean/compatible-variants.rs b/src/test/ui/did_you_mean/compatible-variants.rs
index a70dda8386f08..b078064b26745 100644
--- a/src/test/ui/did_you_mean/compatible-variants.rs
+++ b/src/test/ui/did_you_mean/compatible-variants.rs
@@ -23,6 +23,21 @@ fn b() -> Result<(), ()> {
     //~| HELP try adding an expression
 }
 
+fn c() -> Option<()> {
+    for _ in [1, 2] {
+        //~^ ERROR mismatched types
+        f();
+    }
+    //~^ HELP try adding an expression
+}
+
+fn d() -> Option<()> {
+    c()?
+    //~^ ERROR incompatible types
+    //~| HELP try removing this `?`
+    //~| HELP try adding an expression
+}
+
 fn main() {
     let _: Option<()> = while false {};
     //~^ ERROR mismatched types
diff --git a/src/test/ui/did_you_mean/compatible-variants.stderr b/src/test/ui/did_you_mean/compatible-variants.stderr
index 0dfd8f5c128f6..51c1bf97c4e2c 100644
--- a/src/test/ui/did_you_mean/compatible-variants.stderr
+++ b/src/test/ui/did_you_mean/compatible-variants.stderr
@@ -37,7 +37,52 @@ LL +     Ok(())
    |
 
 error[E0308]: mismatched types
-  --> $DIR/compatible-variants.rs:27:25
+  --> $DIR/compatible-variants.rs:27:5
+   |
+LL |   fn c() -> Option<()> {
+   |             ---------- expected `Option<()>` because of return type
+LL | /     for _ in [1, 2] {
+LL | |
+LL | |         f();
+LL | |     }
+   | |_____^ expected enum `Option`, found `()`
+   |
+   = note:   expected enum `Option<()>`
+           found unit type `()`
+help: try adding an expression at the end of the block
+   |
+LL ~     }
+LL +     None
+   |
+LL ~     }
+LL +     Some(())
+   |
+
+error[E0308]: `?` operator has incompatible types
+  --> $DIR/compatible-variants.rs:35:5
+   |
+LL |     c()?
+   |     ^^^^ expected enum `Option`, found `()`
+   |
+   = note: `?` operator cannot convert from `()` to `Option<()>`
+   = note:   expected enum `Option<()>`
+           found unit type `()`
+help: try removing this `?`
+   |
+LL -     c()?
+LL +     c()
+   | 
+help: try adding an expression at the end of the block
+   |
+LL ~     c()?;
+LL +     None
+   |
+LL ~     c()?;
+LL +     Some(())
+   |
+
+error[E0308]: mismatched types
+  --> $DIR/compatible-variants.rs:42:25
    |
 LL |     let _: Option<()> = while false {};
    |            ----------   ^^^^^^^^^^^^^^ expected enum `Option`, found `()`
@@ -52,7 +97,7 @@ LL |     let _: Option<()> = Some(while false {});
    |                         +++++              +
 
 error[E0308]: mismatched types
-  --> $DIR/compatible-variants.rs:31:9
+  --> $DIR/compatible-variants.rs:46:9
    |
 LL |         while false {}
    |         ^^^^^^^^^^^^^^ expected enum `Option`, found `()`
@@ -69,7 +114,7 @@ LL +         Some(())
    |
 
 error[E0308]: mismatched types
-  --> $DIR/compatible-variants.rs:35:31
+  --> $DIR/compatible-variants.rs:50:31
    |
 LL |     let _: Result<i32, i32> = 1;
    |            ----------------   ^ expected enum `Result`, found integer
@@ -86,7 +131,7 @@ LL |     let _: Result<i32, i32> = Err(1);
    |                               ++++ +
 
 error[E0308]: mismatched types
-  --> $DIR/compatible-variants.rs:38:26
+  --> $DIR/compatible-variants.rs:53:26
    |
 LL |     let _: Option<i32> = 1;
    |            -----------   ^ expected enum `Option`, found integer
@@ -101,7 +146,7 @@ LL |     let _: Option<i32> = Some(1);
    |                          +++++ +
 
 error[E0308]: mismatched types
-  --> $DIR/compatible-variants.rs:41:28
+  --> $DIR/compatible-variants.rs:56:28
    |
 LL |     let _: Hey<i32, i32> = 1;
    |            -------------   ^ expected enum `Hey`, found integer
@@ -118,7 +163,7 @@ LL |     let _: Hey<i32, i32> = Hey::B(1);
    |                            +++++++ +
 
 error[E0308]: mismatched types
-  --> $DIR/compatible-variants.rs:44:29
+  --> $DIR/compatible-variants.rs:59:29
    |
 LL |     let _: Hey<i32, bool> = false;
    |            --------------   ^^^^^ expected enum `Hey`, found `bool`
@@ -133,7 +178,7 @@ LL |     let _: Hey<i32, bool> = Hey::B(false);
    |                             +++++++     +
 
 error[E0308]: mismatched types
-  --> $DIR/compatible-variants.rs:48:19
+  --> $DIR/compatible-variants.rs:63:19
    |
 LL |     let _ = Foo { bar };
    |                   ^^^ expected enum `Option`, found `i32`
@@ -145,6 +190,6 @@ help: try wrapping the expression in `Some`
 LL |     let _ = Foo { bar: Some(bar) };
    |                   ++++++++++   +
 
-error: aborting due to 9 previous errors
+error: aborting due to 11 previous errors
 
 For more information about this error, try `rustc --explain E0308`.
diff --git a/src/test/ui/lint/unused/unused-doc-comments-edge-cases.rs b/src/test/ui/lint/unused/unused-doc-comments-edge-cases.rs
index 258f9e4831f9a..54d86c31fb4fb 100644
--- a/src/test/ui/lint/unused/unused-doc-comments-edge-cases.rs
+++ b/src/test/ui/lint/unused/unused-doc-comments-edge-cases.rs
@@ -29,4 +29,18 @@ fn doc_comment_on_expr(num: u8) -> bool {
 fn doc_comment_on_generic<#[doc = "x"] T>(val: T) {}
 //~^ ERROR: unused doc comment
 
+fn doc_comment_on_block() {
+    /// unused doc comment
+    //~^ ERROR: unused doc comment
+    {
+        let x = 12;
+    }
+}
+
+/// unused doc comment
+//~^ ERROR: unused doc comment
+extern "C" {
+    fn foo();
+}
+
 fn main() {}
diff --git a/src/test/ui/lint/unused/unused-doc-comments-edge-cases.stderr b/src/test/ui/lint/unused/unused-doc-comments-edge-cases.stderr
index 3ce1df71a2ed5..30a96af583af7 100644
--- a/src/test/ui/lint/unused/unused-doc-comments-edge-cases.stderr
+++ b/src/test/ui/lint/unused/unused-doc-comments-edge-cases.stderr
@@ -49,6 +49,32 @@ LL | fn doc_comment_on_generic<#[doc = "x"] T>(val: T) {}
    |
    = help: use `//` for a plain comment
 
+error: unused doc comment
+  --> $DIR/unused-doc-comments-edge-cases.rs:33:5
+   |
+LL |       /// unused doc comment
+   |       ^^^^^^^^^^^^^^^^^^^^^^
+LL |
+LL | /     {
+LL | |         let x = 12;
+LL | |     }
+   | |_____- rustdoc does not generate documentation for expressions
+   |
+   = help: use `//` for a plain comment
+
+error: unused doc comment
+  --> $DIR/unused-doc-comments-edge-cases.rs:40:1
+   |
+LL |   /// unused doc comment
+   |   ^^^^^^^^^^^^^^^^^^^^^^
+LL |
+LL | / extern "C" {
+LL | |     fn foo();
+LL | | }
+   | |_- rustdoc does not generate documentation for extern block
+   |
+   = help: use `//` for a plain comment
+
 error[E0308]: mismatched types
   --> $DIR/unused-doc-comments-edge-cases.rs:14:9
    |
@@ -63,7 +89,7 @@ help: you might have meant to return this value
 LL |         return true;
    |         ++++++     +
 
-error: aborting due to 6 previous errors
+error: aborting due to 8 previous errors
 
 Some errors have detailed explanations: E0308, E0658.
 For more information about an error, try `rustc --explain E0308`.
diff --git a/src/test/ui/moves/use_of_moved_value_clone_suggestions.rs b/src/test/ui/moves/use_of_moved_value_clone_suggestions.rs
new file mode 100644
index 0000000000000..d5c8d4e6bdf2b
--- /dev/null
+++ b/src/test/ui/moves/use_of_moved_value_clone_suggestions.rs
@@ -0,0 +1,6 @@
+// `Rc` is not ever `Copy`, we should not suggest adding `T: Copy` constraint
+fn duplicate_rc<T>(t: std::rc::Rc<T>) -> (std::rc::Rc<T>, std::rc::Rc<T>) {
+    (t, t) //~ use of moved value: `t`
+}
+
+fn main() {}
diff --git a/src/test/ui/moves/use_of_moved_value_clone_suggestions.stderr b/src/test/ui/moves/use_of_moved_value_clone_suggestions.stderr
new file mode 100644
index 0000000000000..c25981e6f8063
--- /dev/null
+++ b/src/test/ui/moves/use_of_moved_value_clone_suggestions.stderr
@@ -0,0 +1,13 @@
+error[E0382]: use of moved value: `t`
+  --> $DIR/use_of_moved_value_clone_suggestions.rs:3:9
+   |
+LL | fn duplicate_rc<T>(t: std::rc::Rc<T>) -> (std::rc::Rc<T>, std::rc::Rc<T>) {
+   |                    - move occurs because `t` has type `Rc<T>`, which does not implement the `Copy` trait
+LL |     (t, t)
+   |      -  ^ value used here after move
+   |      |
+   |      value moved here
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0382`.
diff --git a/src/test/ui/moves/use_of_moved_value_copy_suggestions.fixed b/src/test/ui/moves/use_of_moved_value_copy_suggestions.fixed
new file mode 100644
index 0000000000000..d31046c77006e
--- /dev/null
+++ b/src/test/ui/moves/use_of_moved_value_copy_suggestions.fixed
@@ -0,0 +1,72 @@
+// run-rustfix
+#![allow(dead_code)]
+
+fn duplicate_t<T: Copy>(t: T) -> (T, T) {
+    //~^ HELP consider restricting type parameter `T`
+    (t, t) //~ use of moved value: `t`
+}
+
+fn duplicate_opt<T: Copy>(t: Option<T>) -> (Option<T>, Option<T>) {
+    //~^ HELP consider restricting type parameter `T`
+    (t, t) //~ use of moved value: `t`
+}
+
+fn duplicate_tup1<T: Copy>(t: (T,)) -> ((T,), (T,)) {
+    //~^ HELP consider restricting type parameter `T`
+    (t, t) //~ use of moved value: `t`
+}
+
+fn duplicate_tup2<A: Copy, B: Copy>(t: (A, B)) -> ((A, B), (A, B)) {
+    //~^ HELP consider restricting type parameters
+    (t, t) //~ use of moved value: `t`
+}
+
+fn duplicate_custom<T: Trait + Copy>(t: S<T>) -> (S<T>, S<T>) {
+    //~^ HELP consider restricting type parameter `T`
+    (t, t) //~ use of moved value: `t`
+}
+
+struct S<T>(T);
+trait Trait {}
+impl<T: Trait + Clone> Clone for S<T> {
+    fn clone(&self) -> Self {
+        Self(self.0.clone())
+    }
+}
+impl<T: Trait + Copy> Copy for S<T> {}
+
+trait A {}
+trait B {}
+
+// Test where bounds are added with different bound placements
+fn duplicate_custom_1<T: Trait + Copy>(t: S<T>) -> (S<T>, S<T>) where {
+    //~^ HELP consider restricting type parameter `T`
+    (t, t) //~ use of moved value: `t`
+}
+
+fn duplicate_custom_2<T>(t: S<T>) -> (S<T>, S<T>)
+where
+    T: A + Trait + Copy,
+    //~^ HELP consider further restricting this bound
+{
+    (t, t) //~ use of moved value: `t`
+}
+
+fn duplicate_custom_3<T>(t: S<T>) -> (S<T>, S<T>)
+where
+    T: A,
+    T: B, T: Trait, T: Copy
+    //~^ HELP consider further restricting type parameter `T`
+{
+    (t, t) //~ use of moved value: `t`
+}
+
+fn duplicate_custom_4<T: A>(t: S<T>) -> (S<T>, S<T>)
+where
+    T: B + Trait + Copy,
+    //~^ HELP consider further restricting this bound
+{
+    (t, t) //~ use of moved value: `t`
+}
+
+fn main() {}
diff --git a/src/test/ui/moves/use_of_moved_value_copy_suggestions.rs b/src/test/ui/moves/use_of_moved_value_copy_suggestions.rs
new file mode 100644
index 0000000000000..7cc5189fac017
--- /dev/null
+++ b/src/test/ui/moves/use_of_moved_value_copy_suggestions.rs
@@ -0,0 +1,72 @@
+// run-rustfix
+#![allow(dead_code)]
+
+fn duplicate_t<T>(t: T) -> (T, T) {
+    //~^ HELP consider restricting type parameter `T`
+    (t, t) //~ use of moved value: `t`
+}
+
+fn duplicate_opt<T>(t: Option<T>) -> (Option<T>, Option<T>) {
+    //~^ HELP consider restricting type parameter `T`
+    (t, t) //~ use of moved value: `t`
+}
+
+fn duplicate_tup1<T>(t: (T,)) -> ((T,), (T,)) {
+    //~^ HELP consider restricting type parameter `T`
+    (t, t) //~ use of moved value: `t`
+}
+
+fn duplicate_tup2<A, B>(t: (A, B)) -> ((A, B), (A, B)) {
+    //~^ HELP consider restricting type parameters
+    (t, t) //~ use of moved value: `t`
+}
+
+fn duplicate_custom<T>(t: S<T>) -> (S<T>, S<T>) {
+    //~^ HELP consider restricting type parameter `T`
+    (t, t) //~ use of moved value: `t`
+}
+
+struct S<T>(T);
+trait Trait {}
+impl<T: Trait + Clone> Clone for S<T> {
+    fn clone(&self) -> Self {
+        Self(self.0.clone())
+    }
+}
+impl<T: Trait + Copy> Copy for S<T> {}
+
+trait A {}
+trait B {}
+
+// Test where bounds are added with different bound placements
+fn duplicate_custom_1<T>(t: S<T>) -> (S<T>, S<T>) where {
+    //~^ HELP consider restricting type parameter `T`
+    (t, t) //~ use of moved value: `t`
+}
+
+fn duplicate_custom_2<T>(t: S<T>) -> (S<T>, S<T>)
+where
+    T: A,
+    //~^ HELP consider further restricting this bound
+{
+    (t, t) //~ use of moved value: `t`
+}
+
+fn duplicate_custom_3<T>(t: S<T>) -> (S<T>, S<T>)
+where
+    T: A,
+    T: B,
+    //~^ HELP consider further restricting type parameter `T`
+{
+    (t, t) //~ use of moved value: `t`
+}
+
+fn duplicate_custom_4<T: A>(t: S<T>) -> (S<T>, S<T>)
+where
+    T: B,
+    //~^ HELP consider further restricting this bound
+{
+    (t, t) //~ use of moved value: `t`
+}
+
+fn main() {}
diff --git a/src/test/ui/moves/use_of_moved_value_copy_suggestions.stderr b/src/test/ui/moves/use_of_moved_value_copy_suggestions.stderr
new file mode 100644
index 0000000000000..8e72697ca30bb
--- /dev/null
+++ b/src/test/ui/moves/use_of_moved_value_copy_suggestions.stderr
@@ -0,0 +1,147 @@
+error[E0382]: use of moved value: `t`
+  --> $DIR/use_of_moved_value_copy_suggestions.rs:6:9
+   |
+LL | fn duplicate_t<T>(t: T) -> (T, T) {
+   |                   - move occurs because `t` has type `T`, which does not implement the `Copy` trait
+LL |
+LL |     (t, t)
+   |      -  ^ value used here after move
+   |      |
+   |      value moved here
+   |
+help: consider restricting type parameter `T`
+   |
+LL | fn duplicate_t<T: Copy>(t: T) -> (T, T) {
+   |                 ++++++
+
+error[E0382]: use of moved value: `t`
+  --> $DIR/use_of_moved_value_copy_suggestions.rs:11:9
+   |
+LL | fn duplicate_opt<T>(t: Option<T>) -> (Option<T>, Option<T>) {
+   |                     - move occurs because `t` has type `Option<T>`, which does not implement the `Copy` trait
+LL |
+LL |     (t, t)
+   |      -  ^ value used here after move
+   |      |
+   |      value moved here
+   |
+help: consider restricting type parameter `T`
+   |
+LL | fn duplicate_opt<T: Copy>(t: Option<T>) -> (Option<T>, Option<T>) {
+   |                   ++++++
+
+error[E0382]: use of moved value: `t`
+  --> $DIR/use_of_moved_value_copy_suggestions.rs:16:9
+   |
+LL | fn duplicate_tup1<T>(t: (T,)) -> ((T,), (T,)) {
+   |                      - move occurs because `t` has type `(T,)`, which does not implement the `Copy` trait
+LL |
+LL |     (t, t)
+   |      -  ^ value used here after move
+   |      |
+   |      value moved here
+   |
+help: consider restricting type parameter `T`
+   |
+LL | fn duplicate_tup1<T: Copy>(t: (T,)) -> ((T,), (T,)) {
+   |                    ++++++
+
+error[E0382]: use of moved value: `t`
+  --> $DIR/use_of_moved_value_copy_suggestions.rs:21:9
+   |
+LL | fn duplicate_tup2<A, B>(t: (A, B)) -> ((A, B), (A, B)) {
+   |                         - move occurs because `t` has type `(A, B)`, which does not implement the `Copy` trait
+LL |
+LL |     (t, t)
+   |      -  ^ value used here after move
+   |      |
+   |      value moved here
+   |
+help: consider restricting type parameters
+   |
+LL | fn duplicate_tup2<A: Copy, B: Copy>(t: (A, B)) -> ((A, B), (A, B)) {
+   |                    ++++++   ++++++
+
+error[E0382]: use of moved value: `t`
+  --> $DIR/use_of_moved_value_copy_suggestions.rs:26:9
+   |
+LL | fn duplicate_custom<T>(t: S<T>) -> (S<T>, S<T>) {
+   |                        - move occurs because `t` has type `S<T>`, which does not implement the `Copy` trait
+LL |
+LL |     (t, t)
+   |      -  ^ value used here after move
+   |      |
+   |      value moved here
+   |
+help: consider restricting type parameter `T`
+   |
+LL | fn duplicate_custom<T: Trait + Copy>(t: S<T>) -> (S<T>, S<T>) {
+   |                      ++++++++++++++
+
+error[E0382]: use of moved value: `t`
+  --> $DIR/use_of_moved_value_copy_suggestions.rs:44:9
+   |
+LL | fn duplicate_custom_1<T>(t: S<T>) -> (S<T>, S<T>) where {
+   |                          - move occurs because `t` has type `S<T>`, which does not implement the `Copy` trait
+LL |
+LL |     (t, t)
+   |      -  ^ value used here after move
+   |      |
+   |      value moved here
+   |
+help: consider restricting type parameter `T`
+   |
+LL | fn duplicate_custom_1<T: Trait + Copy>(t: S<T>) -> (S<T>, S<T>) where {
+   |                        ++++++++++++++
+
+error[E0382]: use of moved value: `t`
+  --> $DIR/use_of_moved_value_copy_suggestions.rs:52:9
+   |
+LL | fn duplicate_custom_2<T>(t: S<T>) -> (S<T>, S<T>)
+   |                          - move occurs because `t` has type `S<T>`, which does not implement the `Copy` trait
+...
+LL |     (t, t)
+   |      -  ^ value used here after move
+   |      |
+   |      value moved here
+   |
+help: consider further restricting this bound
+   |
+LL |     T: A + Trait + Copy,
+   |          ++++++++++++++
+
+error[E0382]: use of moved value: `t`
+  --> $DIR/use_of_moved_value_copy_suggestions.rs:61:9
+   |
+LL | fn duplicate_custom_3<T>(t: S<T>) -> (S<T>, S<T>)
+   |                          - move occurs because `t` has type `S<T>`, which does not implement the `Copy` trait
+...
+LL |     (t, t)
+   |      -  ^ value used here after move
+   |      |
+   |      value moved here
+   |
+help: consider further restricting type parameter `T`
+   |
+LL |     T: B, T: Trait, T: Copy
+   |         ~~~~~~~~~~~~~~~~~~~
+
+error[E0382]: use of moved value: `t`
+  --> $DIR/use_of_moved_value_copy_suggestions.rs:69:9
+   |
+LL | fn duplicate_custom_4<T: A>(t: S<T>) -> (S<T>, S<T>)
+   |                             - move occurs because `t` has type `S<T>`, which does not implement the `Copy` trait
+...
+LL |     (t, t)
+   |      -  ^ value used here after move
+   |      |
+   |      value moved here
+   |
+help: consider further restricting this bound
+   |
+LL |     T: B + Trait + Copy,
+   |          ++++++++++++++
+
+error: aborting due to 9 previous errors
+
+For more information about this error, try `rustc --explain E0382`.
diff --git a/src/test/ui/numbers-arithmetic/issue-8460-const.noopt.stderr b/src/test/ui/numbers-arithmetic/issue-8460-const.noopt.stderr
index d94c7742de301..e2eee1ccdc98c 100644
--- a/src/test/ui/numbers-arithmetic/issue-8460-const.noopt.stderr
+++ b/src/test/ui/numbers-arithmetic/issue-8460-const.noopt.stderr
@@ -1,36 +1,36 @@
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:13:36
    |
 LL |     assert!(thread::spawn(move|| { isize::MIN / -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^^^^ attempt to compute `isize::MIN / -1_isize`, which would overflow
    |
-   = note: `#[deny(arithmetic_overflow)]` on by default
+   = note: `#[deny(unconditional_panic)]` on by default
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:15:36
    |
 LL |     assert!(thread::spawn(move|| { i8::MIN / -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^ attempt to compute `i8::MIN / -1_i8`, which would overflow
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:17:36
    |
 LL |     assert!(thread::spawn(move|| { i16::MIN / -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^^ attempt to compute `i16::MIN / -1_i16`, which would overflow
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:19:36
    |
 LL |     assert!(thread::spawn(move|| { i32::MIN / -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^^ attempt to compute `i32::MIN / -1_i32`, which would overflow
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:21:36
    |
 LL |     assert!(thread::spawn(move|| { i64::MIN / -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^^ attempt to compute `i64::MIN / -1_i64`, which would overflow
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:23:36
    |
 LL |     assert!(thread::spawn(move|| { i128::MIN / -1; }).join().is_err());
@@ -41,8 +41,6 @@ error: this operation will panic at runtime
    |
 LL |     assert!(thread::spawn(move|| { 1isize / 0; }).join().is_err());
    |                                    ^^^^^^^^^^ attempt to divide `1_isize` by zero
-   |
-   = note: `#[deny(unconditional_panic)]` on by default
 
 error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:27:36
@@ -74,37 +72,37 @@ error: this operation will panic at runtime
 LL |     assert!(thread::spawn(move|| { 1i128 / 0; }).join().is_err());
    |                                    ^^^^^^^^^ attempt to divide `1_i128` by zero
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:37:36
    |
 LL |     assert!(thread::spawn(move|| { isize::MIN % -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^^^^ attempt to compute the remainder of `isize::MIN % -1_isize`, which would overflow
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:39:36
    |
 LL |     assert!(thread::spawn(move|| { i8::MIN % -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^ attempt to compute the remainder of `i8::MIN % -1_i8`, which would overflow
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:41:36
    |
 LL |     assert!(thread::spawn(move|| { i16::MIN % -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^^ attempt to compute the remainder of `i16::MIN % -1_i16`, which would overflow
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:43:36
    |
 LL |     assert!(thread::spawn(move|| { i32::MIN % -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^^ attempt to compute the remainder of `i32::MIN % -1_i32`, which would overflow
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:45:36
    |
 LL |     assert!(thread::spawn(move|| { i64::MIN % -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^^ attempt to compute the remainder of `i64::MIN % -1_i64`, which would overflow
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:47:36
    |
 LL |     assert!(thread::spawn(move|| { i128::MIN % -1; }).join().is_err());
diff --git a/src/test/ui/numbers-arithmetic/issue-8460-const.opt.stderr b/src/test/ui/numbers-arithmetic/issue-8460-const.opt.stderr
index d94c7742de301..e2eee1ccdc98c 100644
--- a/src/test/ui/numbers-arithmetic/issue-8460-const.opt.stderr
+++ b/src/test/ui/numbers-arithmetic/issue-8460-const.opt.stderr
@@ -1,36 +1,36 @@
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:13:36
    |
 LL |     assert!(thread::spawn(move|| { isize::MIN / -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^^^^ attempt to compute `isize::MIN / -1_isize`, which would overflow
    |
-   = note: `#[deny(arithmetic_overflow)]` on by default
+   = note: `#[deny(unconditional_panic)]` on by default
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:15:36
    |
 LL |     assert!(thread::spawn(move|| { i8::MIN / -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^ attempt to compute `i8::MIN / -1_i8`, which would overflow
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:17:36
    |
 LL |     assert!(thread::spawn(move|| { i16::MIN / -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^^ attempt to compute `i16::MIN / -1_i16`, which would overflow
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:19:36
    |
 LL |     assert!(thread::spawn(move|| { i32::MIN / -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^^ attempt to compute `i32::MIN / -1_i32`, which would overflow
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:21:36
    |
 LL |     assert!(thread::spawn(move|| { i64::MIN / -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^^ attempt to compute `i64::MIN / -1_i64`, which would overflow
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:23:36
    |
 LL |     assert!(thread::spawn(move|| { i128::MIN / -1; }).join().is_err());
@@ -41,8 +41,6 @@ error: this operation will panic at runtime
    |
 LL |     assert!(thread::spawn(move|| { 1isize / 0; }).join().is_err());
    |                                    ^^^^^^^^^^ attempt to divide `1_isize` by zero
-   |
-   = note: `#[deny(unconditional_panic)]` on by default
 
 error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:27:36
@@ -74,37 +72,37 @@ error: this operation will panic at runtime
 LL |     assert!(thread::spawn(move|| { 1i128 / 0; }).join().is_err());
    |                                    ^^^^^^^^^ attempt to divide `1_i128` by zero
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:37:36
    |
 LL |     assert!(thread::spawn(move|| { isize::MIN % -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^^^^ attempt to compute the remainder of `isize::MIN % -1_isize`, which would overflow
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:39:36
    |
 LL |     assert!(thread::spawn(move|| { i8::MIN % -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^ attempt to compute the remainder of `i8::MIN % -1_i8`, which would overflow
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:41:36
    |
 LL |     assert!(thread::spawn(move|| { i16::MIN % -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^^ attempt to compute the remainder of `i16::MIN % -1_i16`, which would overflow
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:43:36
    |
 LL |     assert!(thread::spawn(move|| { i32::MIN % -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^^ attempt to compute the remainder of `i32::MIN % -1_i32`, which would overflow
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:45:36
    |
 LL |     assert!(thread::spawn(move|| { i64::MIN % -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^^ attempt to compute the remainder of `i64::MIN % -1_i64`, which would overflow
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:47:36
    |
 LL |     assert!(thread::spawn(move|| { i128::MIN % -1; }).join().is_err());
diff --git a/src/test/ui/numbers-arithmetic/issue-8460-const.opt_with_overflow_checks.stderr b/src/test/ui/numbers-arithmetic/issue-8460-const.opt_with_overflow_checks.stderr
index d94c7742de301..e2eee1ccdc98c 100644
--- a/src/test/ui/numbers-arithmetic/issue-8460-const.opt_with_overflow_checks.stderr
+++ b/src/test/ui/numbers-arithmetic/issue-8460-const.opt_with_overflow_checks.stderr
@@ -1,36 +1,36 @@
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:13:36
    |
 LL |     assert!(thread::spawn(move|| { isize::MIN / -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^^^^ attempt to compute `isize::MIN / -1_isize`, which would overflow
    |
-   = note: `#[deny(arithmetic_overflow)]` on by default
+   = note: `#[deny(unconditional_panic)]` on by default
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:15:36
    |
 LL |     assert!(thread::spawn(move|| { i8::MIN / -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^ attempt to compute `i8::MIN / -1_i8`, which would overflow
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:17:36
    |
 LL |     assert!(thread::spawn(move|| { i16::MIN / -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^^ attempt to compute `i16::MIN / -1_i16`, which would overflow
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:19:36
    |
 LL |     assert!(thread::spawn(move|| { i32::MIN / -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^^ attempt to compute `i32::MIN / -1_i32`, which would overflow
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:21:36
    |
 LL |     assert!(thread::spawn(move|| { i64::MIN / -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^^ attempt to compute `i64::MIN / -1_i64`, which would overflow
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:23:36
    |
 LL |     assert!(thread::spawn(move|| { i128::MIN / -1; }).join().is_err());
@@ -41,8 +41,6 @@ error: this operation will panic at runtime
    |
 LL |     assert!(thread::spawn(move|| { 1isize / 0; }).join().is_err());
    |                                    ^^^^^^^^^^ attempt to divide `1_isize` by zero
-   |
-   = note: `#[deny(unconditional_panic)]` on by default
 
 error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:27:36
@@ -74,37 +72,37 @@ error: this operation will panic at runtime
 LL |     assert!(thread::spawn(move|| { 1i128 / 0; }).join().is_err());
    |                                    ^^^^^^^^^ attempt to divide `1_i128` by zero
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:37:36
    |
 LL |     assert!(thread::spawn(move|| { isize::MIN % -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^^^^ attempt to compute the remainder of `isize::MIN % -1_isize`, which would overflow
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:39:36
    |
 LL |     assert!(thread::spawn(move|| { i8::MIN % -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^ attempt to compute the remainder of `i8::MIN % -1_i8`, which would overflow
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:41:36
    |
 LL |     assert!(thread::spawn(move|| { i16::MIN % -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^^ attempt to compute the remainder of `i16::MIN % -1_i16`, which would overflow
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:43:36
    |
 LL |     assert!(thread::spawn(move|| { i32::MIN % -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^^ attempt to compute the remainder of `i32::MIN % -1_i32`, which would overflow
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:45:36
    |
 LL |     assert!(thread::spawn(move|| { i64::MIN % -1; }).join().is_err());
    |                                    ^^^^^^^^^^^^^ attempt to compute the remainder of `i64::MIN % -1_i64`, which would overflow
 
-error: this arithmetic operation will overflow
+error: this operation will panic at runtime
   --> $DIR/issue-8460-const.rs:47:36
    |
 LL |     assert!(thread::spawn(move|| { i128::MIN % -1; }).join().is_err());
diff --git a/src/test/ui/numbers-arithmetic/issue-8460-const.rs b/src/test/ui/numbers-arithmetic/issue-8460-const.rs
index dc754666c8e1f..8cad6deb3db5e 100644
--- a/src/test/ui/numbers-arithmetic/issue-8460-const.rs
+++ b/src/test/ui/numbers-arithmetic/issue-8460-const.rs
@@ -11,17 +11,17 @@ use std::thread;
 
 fn main() {
     assert!(thread::spawn(move|| { isize::MIN / -1; }).join().is_err());
-    //~^ ERROR arithmetic operation will overflow
+    //~^ ERROR operation will panic
     assert!(thread::spawn(move|| { i8::MIN / -1; }).join().is_err());
-    //~^ ERROR arithmetic operation will overflow
+    //~^ ERROR operation will panic
     assert!(thread::spawn(move|| { i16::MIN / -1; }).join().is_err());
-    //~^ ERROR arithmetic operation will overflow
+    //~^ ERROR operation will panic
     assert!(thread::spawn(move|| { i32::MIN / -1; }).join().is_err());
-    //~^ ERROR arithmetic operation will overflow
+    //~^ ERROR operation will panic
     assert!(thread::spawn(move|| { i64::MIN / -1; }).join().is_err());
-    //~^ ERROR arithmetic operation will overflow
+    //~^ ERROR operation will panic
     assert!(thread::spawn(move|| { i128::MIN / -1; }).join().is_err());
-    //~^ ERROR arithmetic operation will overflow
+    //~^ ERROR operation will panic
     assert!(thread::spawn(move|| { 1isize / 0; }).join().is_err());
     //~^ ERROR operation will panic
     assert!(thread::spawn(move|| { 1i8 / 0; }).join().is_err());
@@ -35,17 +35,17 @@ fn main() {
     assert!(thread::spawn(move|| { 1i128 / 0; }).join().is_err());
     //~^ ERROR operation will panic
     assert!(thread::spawn(move|| { isize::MIN % -1; }).join().is_err());
-    //~^ ERROR arithmetic operation will overflow
+    //~^ ERROR operation will panic
     assert!(thread::spawn(move|| { i8::MIN % -1; }).join().is_err());
-    //~^ ERROR arithmetic operation will overflow
+    //~^ ERROR operation will panic
     assert!(thread::spawn(move|| { i16::MIN % -1; }).join().is_err());
-    //~^ ERROR arithmetic operation will overflow
+    //~^ ERROR operation will panic
     assert!(thread::spawn(move|| { i32::MIN % -1; }).join().is_err());
-    //~^ ERROR arithmetic operation will overflow
+    //~^ ERROR operation will panic
     assert!(thread::spawn(move|| { i64::MIN % -1; }).join().is_err());
-    //~^ ERROR arithmetic operation will overflow
+    //~^ ERROR operation will panic
     assert!(thread::spawn(move|| { i128::MIN % -1; }).join().is_err());
-    //~^ ERROR arithmetic operation will overflow
+    //~^ ERROR operation will panic
     assert!(thread::spawn(move|| { 1isize % 0; }).join().is_err());
     //~^ ERROR operation will panic
     assert!(thread::spawn(move|| { 1i8 % 0; }).join().is_err());
diff --git a/src/tools/build-manifest/Cargo.toml b/src/tools/build-manifest/Cargo.toml
index c022d3aa0acd7..c437bde5ae69a 100644
--- a/src/tools/build-manifest/Cargo.toml
+++ b/src/tools/build-manifest/Cargo.toml
@@ -13,4 +13,3 @@ tar = "0.4.29"
 sha2 = "0.10.1"
 rayon = "1.5.1"
 hex = "0.4.2"
-num_cpus = "1.13.0"
diff --git a/src/tools/build-manifest/src/main.rs b/src/tools/build-manifest/src/main.rs
index 8a62146abfc4e..378efeb644375 100644
--- a/src/tools/build-manifest/src/main.rs
+++ b/src/tools/build-manifest/src/main.rs
@@ -208,7 +208,7 @@ fn main() {
     let num_threads = if let Some(num) = env::var_os("BUILD_MANIFEST_NUM_THREADS") {
         num.to_str().unwrap().parse().expect("invalid number for BUILD_MANIFEST_NUM_THREADS")
     } else {
-        num_cpus::get()
+        std::thread::available_parallelism().map_or(1, std::num::NonZeroUsize::get)
     };
     rayon::ThreadPoolBuilder::new()
         .num_threads(num_threads)