Auto merge of #131672 - matthiaskrgr:rollup-gyzysj4, r=matthiaskrgr

Rollup of 8 pull requests

Successful merges:

 - #128967 (std::fs::get_path freebsd update.)
 - #130629 (core/net: add Ipv[46]Addr::from_octets, Ipv6Addr::from_segments.)
 - #131274 (library: Const-stabilize `MaybeUninit::assume_init_mut`)
 - #131473 (compiler: `{TyAnd,}Layout` comes home)
 - #131533 (emscripten: Use the latest emsdk 3.1.68)
 - #131593 (miri: avoid cloning AllocExtra)
 - #131616 (merge const_ipv4 / const_ipv6 feature gate into 'ip' feature gate)
 - #131660 (Also use outermost const-anon for impl items in `non_local_defs` lint)

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

compiler/rustc_abi/src/callconv.rs

@@ -0,0 +1,254 @@
+mod abi {
+    pub(crate) use crate::Primitive::*;
+    pub(crate) use crate::Variants;
+}
+
+use rustc_macros::HashStable_Generic;
+
+use crate::{Abi, Align, FieldsShape, HasDataLayout, Size, TyAbiInterface, TyAndLayout};
+
+#[derive(Copy, Clone, PartialEq, Eq, Hash, Debug, HashStable_Generic)]
+pub enum RegKind {
+    Integer,
+    Float,
+    Vector,
+}
+
+#[derive(Copy, Clone, PartialEq, Eq, Hash, Debug, HashStable_Generic)]
+pub struct Reg {
+    pub kind: RegKind,
+    pub size: Size,
+}
+
+macro_rules! reg_ctor {
+    ($name:ident, $kind:ident, $bits:expr) => {
+        pub fn $name() -> Reg {
+            Reg { kind: RegKind::$kind, size: Size::from_bits($bits) }
+        }
+    };
+}
+
+impl Reg {
+    reg_ctor!(i8, Integer, 8);
+    reg_ctor!(i16, Integer, 16);
+    reg_ctor!(i32, Integer, 32);
+    reg_ctor!(i64, Integer, 64);
+    reg_ctor!(i128, Integer, 128);
+
+    reg_ctor!(f32, Float, 32);
+    reg_ctor!(f64, Float, 64);
+}
+
+impl Reg {
+    pub fn align<C: HasDataLayout>(&self, cx: &C) -> Align {
+        let dl = cx.data_layout();
+        match self.kind {
+            RegKind::Integer => match self.size.bits() {
+                1 => dl.i1_align.abi,
+                2..=8 => dl.i8_align.abi,
+                9..=16 => dl.i16_align.abi,
+                17..=32 => dl.i32_align.abi,
+                33..=64 => dl.i64_align.abi,
+                65..=128 => dl.i128_align.abi,
+                _ => panic!("unsupported integer: {self:?}"),
+            },
+            RegKind::Float => match self.size.bits() {
+                16 => dl.f16_align.abi,
+                32 => dl.f32_align.abi,
+                64 => dl.f64_align.abi,
+                128 => dl.f128_align.abi,
+                _ => panic!("unsupported float: {self:?}"),
+            },
+            RegKind::Vector => dl.vector_align(self.size).abi,
+        }
+    }
+}
+
+/// Return value from the `homogeneous_aggregate` test function.
+#[derive(Copy, Clone, Debug)]
+pub enum HomogeneousAggregate {
+    /// Yes, all the "leaf fields" of this struct are passed in the
+    /// same way (specified in the `Reg` value).
+    Homogeneous(Reg),
+
+    /// There are no leaf fields at all.
+    NoData,
+}
+
+/// Error from the `homogeneous_aggregate` test function, indicating
+/// there are distinct leaf fields passed in different ways,
+/// or this is uninhabited.
+#[derive(Copy, Clone, Debug)]
+pub struct Heterogeneous;
+
+impl HomogeneousAggregate {
+    /// If this is a homogeneous aggregate, returns the homogeneous
+    /// unit, else `None`.
+    pub fn unit(self) -> Option<Reg> {
+        match self {
+            HomogeneousAggregate::Homogeneous(reg) => Some(reg),
+            HomogeneousAggregate::NoData => None,
+        }
+    }
+
+    /// Try to combine two `HomogeneousAggregate`s, e.g. from two fields in
+    /// the same `struct`. Only succeeds if only one of them has any data,
+    /// or both units are identical.
+    fn merge(self, other: HomogeneousAggregate) -> Result<HomogeneousAggregate, Heterogeneous> {
+        match (self, other) {
+            (x, HomogeneousAggregate::NoData) | (HomogeneousAggregate::NoData, x) => Ok(x),
+
+            (HomogeneousAggregate::Homogeneous(a), HomogeneousAggregate::Homogeneous(b)) => {
+                if a != b {
+                    return Err(Heterogeneous);
+                }
+                Ok(self)
+            }
+        }
+    }
+}
+
+impl<'a, Ty> TyAndLayout<'a, Ty> {
+    /// Returns `true` if this is an aggregate type (including a ScalarPair!)
+    pub fn is_aggregate(&self) -> bool {
+        match self.abi {
+            Abi::Uninhabited | Abi::Scalar(_) | Abi::Vector { .. } => false,
+            Abi::ScalarPair(..) | Abi::Aggregate { .. } => true,
+        }
+    }
+
+    /// Returns `Homogeneous` if this layout is an aggregate containing fields of
+    /// only a single type (e.g., `(u32, u32)`). Such aggregates are often
+    /// special-cased in ABIs.
+    ///
+    /// Note: We generally ignore 1-ZST fields when computing this value (see #56877).
+    ///
+    /// This is public so that it can be used in unit tests, but
+    /// should generally only be relevant to the ABI details of
+    /// specific targets.
+    pub fn homogeneous_aggregate<C>(&self, cx: &C) -> Result<HomogeneousAggregate, Heterogeneous>
+    where
+        Ty: TyAbiInterface<'a, C> + Copy,
+    {
+        match self.abi {
+            Abi::Uninhabited => Err(Heterogeneous),
+
+            // The primitive for this algorithm.
+            Abi::Scalar(scalar) => {
+                let kind = match scalar.primitive() {
+                    abi::Int(..) | abi::Pointer(_) => RegKind::Integer,
+                    abi::Float(_) => RegKind::Float,
+                };
+                Ok(HomogeneousAggregate::Homogeneous(Reg { kind, size: self.size }))
+            }
+
+            Abi::Vector { .. } => {
+                assert!(!self.is_zst());
+                Ok(HomogeneousAggregate::Homogeneous(Reg {
+                    kind: RegKind::Vector,
+                    size: self.size,
+                }))
+            }
+
+            Abi::ScalarPair(..) | Abi::Aggregate { sized: true } => {
+                // Helper for computing `homogeneous_aggregate`, allowing a custom
+                // starting offset (used below for handling variants).
+                let from_fields_at =
+                    |layout: Self,
+                     start: Size|
+                     -> Result<(HomogeneousAggregate, Size), Heterogeneous> {
+                        let is_union = match layout.fields {
+                            FieldsShape::Primitive => {
+                                unreachable!("aggregates can't have `FieldsShape::Primitive`")
+                            }
+                            FieldsShape::Array { count, .. } => {
+                                assert_eq!(start, Size::ZERO);
+
+                                let result = if count > 0 {
+                                    layout.field(cx, 0).homogeneous_aggregate(cx)?
+                                } else {
+                                    HomogeneousAggregate::NoData
+                                };
+                                return Ok((result, layout.size));
+                            }
+                            FieldsShape::Union(_) => true,
+                            FieldsShape::Arbitrary { .. } => false,
+                        };
+
+                        let mut result = HomogeneousAggregate::NoData;
+                        let mut total = start;
+
+                        for i in 0..layout.fields.count() {
+                            let field = layout.field(cx, i);
+                            if field.is_1zst() {
+                                // No data here and no impact on layout, can be ignored.
+                                // (We might be able to also ignore all aligned ZST but that's less clear.)
+                                continue;
+                            }
+
+                            if !is_union && total != layout.fields.offset(i) {
+                                // This field isn't just after the previous one we considered, abort.
+                                return Err(Heterogeneous);
+                            }
+
+                            result = result.merge(field.homogeneous_aggregate(cx)?)?;
+
+                            // Keep track of the offset (without padding).
+                            let size = field.size;
+                            if is_union {
+                                total = total.max(size);
+                            } else {
+                                total += size;
+                            }
+                        }
+
+                        Ok((result, total))
+                    };
+
+                let (mut result, mut total) = from_fields_at(*self, Size::ZERO)?;
+
+                match &self.variants {
+                    abi::Variants::Single { .. } => {}
+                    abi::Variants::Multiple { variants, .. } => {
+                        // Treat enum variants like union members.
+                        // HACK(eddyb) pretend the `enum` field (discriminant)
+                        // is at the start of every variant (otherwise the gap
+                        // at the start of all variants would disqualify them).
+                        //
+                        // NB: for all tagged `enum`s (which include all non-C-like
+                        // `enum`s with defined FFI representation), this will
+                        // match the homogeneous computation on the equivalent
+                        // `struct { tag; union { variant1; ... } }` and/or
+                        // `union { struct { tag; variant1; } ... }`
+                        // (the offsets of variant fields should be identical
+                        // between the two for either to be a homogeneous aggregate).
+                        let variant_start = total;
+                        for variant_idx in variants.indices() {
+                            let (variant_result, variant_total) =
+                                from_fields_at(self.for_variant(cx, variant_idx), variant_start)?;
+
+                            result = result.merge(variant_result)?;
+                            total = total.max(variant_total);
+                        }
+                    }
+                }
+
+                // There needs to be no padding.
+                if total != self.size {
+                    Err(Heterogeneous)
+                } else {
+                    match result {
+                        HomogeneousAggregate::Homogeneous(_) => {
+                            assert_ne!(total, Size::ZERO);
+                        }
+                        HomogeneousAggregate::NoData => {
+                            assert_eq!(total, Size::ZERO);
+                        }
+                    }
+                    Ok(result)
+                }
+            }
+            Abi::Aggregate { sized: false } => Err(Heterogeneous),
+        }
+    }
+}

compiler/rustc_abi/src/layout.rs

@@ -11,6 +11,10 @@ use crate::{
     Variants, WrappingRange,
 };
 
+mod ty;
+
+pub use ty::{FIRST_VARIANT, FieldIdx, Layout, TyAbiInterface, TyAndLayout, VariantIdx};
+
 // A variant is absent if it's uninhabited and only has ZST fields.
 // Present uninhabited variants only require space for their fields,
 // but *not* an encoding of the discriminant (e.g., a tag value).

compiler/rustc_abi/src/layout/ty.rs

@@ -6,18 +6,8 @@ use Primitive::*;
 use rustc_data_structures::intern::Interned;
 use rustc_macros::HashStable_Generic;
 
-use crate::json::{Json, ToJson};
-
-pub mod call;
-
 // Explicitly import `Float` to avoid ambiguity with `Primitive::Float`.
-pub use rustc_abi::{Float, *};
+use crate::{Float, *};
-
-impl ToJson for Endian {
-    fn to_json(&self) -> Json {
-        self.as_str().to_json()
-    }
-}
 
 rustc_index::newtype_index! {
     /// The *source-order* index of a field in a variant.

compiler/rustc_abi/src/lib.rs

@@ -1,6 +1,7 @@
 // tidy-alphabetical-start
 #![cfg_attr(feature = "nightly", allow(internal_features))]
 #![cfg_attr(feature = "nightly", doc(rust_logo))]
+#![cfg_attr(feature = "nightly", feature(rustc_attrs))]
 #![cfg_attr(feature = "nightly", feature(rustdoc_internals))]
 #![cfg_attr(feature = "nightly", feature(step_trait))]
 #![warn(unreachable_pub)]
@@ -22,11 +23,16 @@ use rustc_macros::HashStable_Generic;
 #[cfg(feature = "nightly")]
 use rustc_macros::{Decodable_Generic, Encodable_Generic};
 
+mod callconv;
 mod layout;
 #[cfg(test)]
 mod tests;
 
-pub use layout::{LayoutCalculator, LayoutCalculatorError};
+pub use callconv::{Heterogeneous, HomogeneousAggregate, Reg, RegKind};
+pub use layout::{
+    FIRST_VARIANT, FieldIdx, Layout, LayoutCalculator, LayoutCalculatorError, TyAbiInterface,
+    TyAndLayout, VariantIdx,
+};
 
 /// Requirements for a `StableHashingContext` to be used in this crate.
 /// This is a hack to allow using the `HashStable_Generic` derive macro

compiler/rustc_const_eval/src/const_eval/machine.rs

@@ -140,7 +140,7 @@ impl<K: Hash + Eq, V> interpret::AllocMap<K, V> for FxIndexMap<K, V> {
 
     #[inline(always)]
     fn filter_map_collect<T>(&self, mut f: impl FnMut(&K, &V) -> Option<T>) -> Vec<T> {
-        self.iter().filter_map(move |(k, v)| f(k, &*v)).collect()
+        self.iter().filter_map(move |(k, v)| f(k, v)).collect()
     }
 
     #[inline(always)]

compiler/rustc_const_eval/src/interpret/memory.rs

@@ -993,11 +993,14 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
         bytes
     }
 
-    /// Find leaked allocations. Allocations reachable from `static_roots` or a `Global` allocation
+    /// Find leaked allocations, remove them from memory and return them. Allocations reachable from
-    /// are not considered leaked, as well as leaks whose kind's `may_leak()` returns true.
+    /// `static_roots` or a `Global` allocation are not considered leaked, as well as leaks whose
-    pub fn find_leaked_allocations(
+    /// kind's `may_leak()` returns true.
-        &self,
+    ///
-        static_roots: &[AllocId],
+    /// This is highly destructive, no more execution can happen after this!
+    pub fn take_leaked_allocations(
+        &mut self,
+        static_roots: impl FnOnce(&Self) -> &[AllocId],
     ) -> Vec<(AllocId, MemoryKind<M::MemoryKind>, Allocation<M::Provenance, M::AllocExtra, M::Bytes>)>
     {
         // Collect the set of allocations that are *reachable* from `Global` allocations.
@@ -1008,7 +1011,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
                 self.memory.alloc_map.filter_map_collect(move |&id, &(kind, _)| {
                     if Some(kind) == global_kind { Some(id) } else { None }
                 });
-            todo.extend(static_roots);
+            todo.extend(static_roots(self));
             while let Some(id) = todo.pop() {
                 if reachable.insert(id) {
                     // This is a new allocation, add the allocation it points to `todo`.
@@ -1023,13 +1026,15 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
         };
 
         // All allocations that are *not* `reachable` and *not* `may_leak` are considered leaking.
-        self.memory.alloc_map.filter_map_collect(|id, (kind, alloc)| {
+        let leaked: Vec<_> = self.memory.alloc_map.filter_map_collect(|&id, &(kind, _)| {
-            if kind.may_leak() || reachable.contains(id) {
+            if kind.may_leak() || reachable.contains(&id) { None } else { Some(id) }
-                None
+        });
-            } else {
+        let mut result = Vec::new();
-                Some((*id, *kind, alloc.clone()))
+        for &id in leaked.iter() {
-            }
+            let (kind, alloc) = self.memory.alloc_map.remove(&id).unwrap();
-        })
+            result.push((id, kind, alloc));
+        }
+        result
     }
 
     /// Runs the closure in "validation" mode, which means the machine's memory read hooks will be

compiler/rustc_lint/src/non_local_def.rs

@@ -301,9 +301,13 @@ fn did_has_local_parent(
         return false;
     };
 
-    peel_parent_while(tcx, parent_did, |tcx, did| tcx.def_kind(did) == DefKind::Mod)
+    peel_parent_while(tcx, parent_did, |tcx, did| {
-        .map(|parent_did| parent_did == impl_parent || Some(parent_did) == outermost_impl_parent)
+        tcx.def_kind(did) == DefKind::Mod
-        .unwrap_or(false)
+            || (tcx.def_kind(did) == DefKind::Const
+                && tcx.opt_item_name(did) == Some(kw::Underscore))
+    })
+    .map(|parent_did| parent_did == impl_parent || Some(parent_did) == outermost_impl_parent)
+    .unwrap_or(false)
 }
 
 /// Given a `DefId` checks if it satisfies `f` if it does check with it's parent and continue

compiler/rustc_middle/src/ty/context.rs

@@ -12,6 +12,7 @@ use std::marker::PhantomData;
 use std::ops::{Bound, Deref};
 use std::{fmt, iter, mem};
 
+use rustc_abi::{FieldIdx, Layout, LayoutS, TargetDataLayout, VariantIdx};
 use rustc_ast::{self as ast, attr};
 use rustc_data_structures::defer;
 use rustc_data_structures::fingerprint::Fingerprint;
@@ -48,7 +49,6 @@ use rustc_session::{Limit, MetadataKind, Session};
 use rustc_span::def_id::{CRATE_DEF_ID, DefPathHash, StableCrateId};
 use rustc_span::symbol::{Ident, Symbol, kw, sym};
 use rustc_span::{DUMMY_SP, Span};
-use rustc_target::abi::{FieldIdx, Layout, LayoutS, TargetDataLayout, VariantIdx};
 use rustc_target::spec::abi;
 use rustc_type_ir::TyKind::*;
 use rustc_type_ir::fold::TypeFoldable;

compiler/rustc_target/src/callconv/mod.rs

@@ -1,10 +1,11 @@
 use std::fmt;
 use std::str::FromStr;
 
+pub use rustc_abi::{Reg, RegKind};
 use rustc_macros::HashStable_Generic;
 use rustc_span::Symbol;
 
-use crate::abi::{self, Abi, Align, FieldsShape, HasDataLayout, Size, TyAbiInterface, TyAndLayout};
+use crate::abi::{self, Abi, Align, HasDataLayout, Size, TyAbiInterface, TyAndLayout};
 use crate::spec::{self, HasTargetSpec, HasWasmCAbiOpt, WasmCAbi};
 
 mod aarch64;
@@ -192,63 +193,6 @@ impl ArgAttributes {
     }
 }
 
-#[derive(Copy, Clone, PartialEq, Eq, Hash, Debug, HashStable_Generic)]
-pub enum RegKind {
-    Integer,
-    Float,
-    Vector,
-}
-
-#[derive(Copy, Clone, PartialEq, Eq, Hash, Debug, HashStable_Generic)]
-pub struct Reg {
-    pub kind: RegKind,
-    pub size: Size,
-}
-
-macro_rules! reg_ctor {
-    ($name:ident, $kind:ident, $bits:expr) => {
-        pub fn $name() -> Reg {
-            Reg { kind: RegKind::$kind, size: Size::from_bits($bits) }
-        }
-    };
-}
-
-impl Reg {
-    reg_ctor!(i8, Integer, 8);
-    reg_ctor!(i16, Integer, 16);
-    reg_ctor!(i32, Integer, 32);
-    reg_ctor!(i64, Integer, 64);
-    reg_ctor!(i128, Integer, 128);
-
-    reg_ctor!(f32, Float, 32);
-    reg_ctor!(f64, Float, 64);
-}
-
-impl Reg {
-    pub fn align<C: HasDataLayout>(&self, cx: &C) -> Align {
-        let dl = cx.data_layout();
-        match self.kind {
-            RegKind::Integer => match self.size.bits() {
-                1 => dl.i1_align.abi,
-                2..=8 => dl.i8_align.abi,
-                9..=16 => dl.i16_align.abi,
-                17..=32 => dl.i32_align.abi,
-                33..=64 => dl.i64_align.abi,
-                65..=128 => dl.i128_align.abi,
-                _ => panic!("unsupported integer: {self:?}"),
-            },
-            RegKind::Float => match self.size.bits() {
-                16 => dl.f16_align.abi,
-                32 => dl.f32_align.abi,
-                64 => dl.f64_align.abi,
-                128 => dl.f128_align.abi,
-                _ => panic!("unsupported float: {self:?}"),
-            },
-            RegKind::Vector => dl.vector_align(self.size).abi,
-        }
-    }
-}
-
 /// An argument passed entirely registers with the
 /// same kind (e.g., HFA / HVA on PPC64 and AArch64).
 #[derive(Clone, Copy, PartialEq, Eq, Hash, Debug, HashStable_Generic)]
@@ -380,195 +324,6 @@ impl CastTarget {
     }
 }
 
-/// Return value from the `homogeneous_aggregate` test function.
-#[derive(Copy, Clone, Debug)]
-pub enum HomogeneousAggregate {
-    /// Yes, all the "leaf fields" of this struct are passed in the
-    /// same way (specified in the `Reg` value).
-    Homogeneous(Reg),
-
-    /// There are no leaf fields at all.
-    NoData,
-}
-
-/// Error from the `homogeneous_aggregate` test function, indicating
-/// there are distinct leaf fields passed in different ways,
-/// or this is uninhabited.
-#[derive(Copy, Clone, Debug)]
-pub struct Heterogeneous;
-
-impl HomogeneousAggregate {
-    /// If this is a homogeneous aggregate, returns the homogeneous
-    /// unit, else `None`.
-    pub fn unit(self) -> Option<Reg> {
-        match self {
-            HomogeneousAggregate::Homogeneous(reg) => Some(reg),
-            HomogeneousAggregate::NoData => None,
-        }
-    }
-
-    /// Try to combine two `HomogeneousAggregate`s, e.g. from two fields in
-    /// the same `struct`. Only succeeds if only one of them has any data,
-    /// or both units are identical.
-    fn merge(self, other: HomogeneousAggregate) -> Result<HomogeneousAggregate, Heterogeneous> {
-        match (self, other) {
-            (x, HomogeneousAggregate::NoData) | (HomogeneousAggregate::NoData, x) => Ok(x),
-
-            (HomogeneousAggregate::Homogeneous(a), HomogeneousAggregate::Homogeneous(b)) => {
-                if a != b {
-                    return Err(Heterogeneous);
-                }
-                Ok(self)
-            }
-        }
-    }
-}
-
-impl<'a, Ty> TyAndLayout<'a, Ty> {
-    /// Returns `true` if this is an aggregate type (including a ScalarPair!)
-    fn is_aggregate(&self) -> bool {
-        match self.abi {
-            Abi::Uninhabited | Abi::Scalar(_) | Abi::Vector { .. } => false,
-            Abi::ScalarPair(..) | Abi::Aggregate { .. } => true,
-        }
-    }
-
-    /// Returns `Homogeneous` if this layout is an aggregate containing fields of
-    /// only a single type (e.g., `(u32, u32)`). Such aggregates are often
-    /// special-cased in ABIs.
-    ///
-    /// Note: We generally ignore 1-ZST fields when computing this value (see #56877).
-    ///
-    /// This is public so that it can be used in unit tests, but
-    /// should generally only be relevant to the ABI details of
-    /// specific targets.
-    pub fn homogeneous_aggregate<C>(&self, cx: &C) -> Result<HomogeneousAggregate, Heterogeneous>
-    where
-        Ty: TyAbiInterface<'a, C> + Copy,
-    {
-        match self.abi {
-            Abi::Uninhabited => Err(Heterogeneous),
-
-            // The primitive for this algorithm.
-            Abi::Scalar(scalar) => {
-                let kind = match scalar.primitive() {
-                    abi::Int(..) | abi::Pointer(_) => RegKind::Integer,
-                    abi::Float(_) => RegKind::Float,
-                };
-                Ok(HomogeneousAggregate::Homogeneous(Reg { kind, size: self.size }))
-            }
-
-            Abi::Vector { .. } => {
-                assert!(!self.is_zst());
-                Ok(HomogeneousAggregate::Homogeneous(Reg {
-                    kind: RegKind::Vector,
-                    size: self.size,
-                }))
-            }
-
-            Abi::ScalarPair(..) | Abi::Aggregate { sized: true } => {
-                // Helper for computing `homogeneous_aggregate`, allowing a custom
-                // starting offset (used below for handling variants).
-                let from_fields_at =
-                    |layout: Self,
-                     start: Size|
-                     -> Result<(HomogeneousAggregate, Size), Heterogeneous> {
-                        let is_union = match layout.fields {
-                            FieldsShape::Primitive => {
-                                unreachable!("aggregates can't have `FieldsShape::Primitive`")
-                            }
-                            FieldsShape::Array { count, .. } => {
-                                assert_eq!(start, Size::ZERO);
-
-                                let result = if count > 0 {
-                                    layout.field(cx, 0).homogeneous_aggregate(cx)?
-                                } else {
-                                    HomogeneousAggregate::NoData
-                                };
-                                return Ok((result, layout.size));
-                            }
-                            FieldsShape::Union(_) => true,
-                            FieldsShape::Arbitrary { .. } => false,
-                        };
-
-                        let mut result = HomogeneousAggregate::NoData;
-                        let mut total = start;
-
-                        for i in 0..layout.fields.count() {
-                            let field = layout.field(cx, i);
-                            if field.is_1zst() {
-                                // No data here and no impact on layout, can be ignored.
-                                // (We might be able to also ignore all aligned ZST but that's less clear.)
-                                continue;
-                            }
-
-                            if !is_union && total != layout.fields.offset(i) {
-                                // This field isn't just after the previous one we considered, abort.
-                                return Err(Heterogeneous);
-                            }
-
-                            result = result.merge(field.homogeneous_aggregate(cx)?)?;
-
-                            // Keep track of the offset (without padding).
-                            let size = field.size;
-                            if is_union {
-                                total = total.max(size);
-                            } else {
-                                total += size;
-                            }
-                        }
-
-                        Ok((result, total))
-                    };
-
-                let (mut result, mut total) = from_fields_at(*self, Size::ZERO)?;
-
-                match &self.variants {
-                    abi::Variants::Single { .. } => {}
-                    abi::Variants::Multiple { variants, .. } => {
-                        // Treat enum variants like union members.
-                        // HACK(eddyb) pretend the `enum` field (discriminant)
-                        // is at the start of every variant (otherwise the gap
-                        // at the start of all variants would disqualify them).
-                        //
-                        // NB: for all tagged `enum`s (which include all non-C-like
-                        // `enum`s with defined FFI representation), this will
-                        // match the homogeneous computation on the equivalent
-                        // `struct { tag; union { variant1; ... } }` and/or
-                        // `union { struct { tag; variant1; } ... }`
-                        // (the offsets of variant fields should be identical
-                        // between the two for either to be a homogeneous aggregate).
-                        let variant_start = total;
-                        for variant_idx in variants.indices() {
-                            let (variant_result, variant_total) =
-                                from_fields_at(self.for_variant(cx, variant_idx), variant_start)?;
-
-                            result = result.merge(variant_result)?;
-                            total = total.max(variant_total);
-                        }
-                    }
-                }
-
-                // There needs to be no padding.
-                if total != self.size {
-                    Err(Heterogeneous)
-                } else {
-                    match result {
-                        HomogeneousAggregate::Homogeneous(_) => {
-                            assert_ne!(total, Size::ZERO);
-                        }
-                        HomogeneousAggregate::NoData => {
-                            assert_eq!(total, Size::ZERO);
-                        }
-                    }
-                    Ok(result)
-                }
-            }
-            Abi::Aggregate { sized: false } => Err(Heterogeneous),
-        }
-    }
-}
-
 /// Information about how to pass an argument to,
 /// or return a value from, a function, under some ABI.
 #[derive(Clone, PartialEq, Eq, Hash, HashStable_Generic)]

compiler/rustc_target/src/json.rs

@@ -134,3 +134,9 @@ impl ToJson for TargetMetadata {
         })
     }
 }
+
+impl ToJson for rustc_abi::Endian {
+    fn to_json(&self) -> Json {
+        self.as_str().to_json()
+    }
+}

compiler/rustc_target/src/lib.rs

@@ -21,8 +21,8 @@
 
 use std::path::{Path, PathBuf};
 
-pub mod abi;
 pub mod asm;
+pub mod callconv;
 pub mod json;
 pub mod spec;
 pub mod target_features;
@@ -30,6 +30,15 @@ pub mod target_features;
 #[cfg(test)]
 mod tests;
 
+pub mod abi {
+    pub(crate) use Float::*;
+    pub(crate) use Primitive::*;
+    // Explicitly import `Float` to avoid ambiguity with `Primitive::Float`.
+    pub use rustc_abi::{Float, *};
+
+    pub use crate::callconv as call;
+}
+
 pub use rustc_abi::HashStableContext;
 
 /// The name of rustc's own place to organize libraries.

library/core/src/lib.rs

@@ -124,11 +124,8 @@
 #![feature(const_hash)]
 #![feature(const_heap)]
 #![feature(const_index_range_slice_index)]
-#![feature(const_ipv4)]
-#![feature(const_ipv6)]
 #![feature(const_likely)]
 #![feature(const_make_ascii)]
-#![feature(const_maybe_uninit_assume_init)]
 #![feature(const_nonnull_new)]
 #![feature(const_num_midpoint)]
 #![feature(const_option_ext)]

library/core/src/mem/maybe_uninit.rs

@@ -913,7 +913,11 @@ impl<T> MaybeUninit<T> {
     /// };
     /// ```
     #[stable(feature = "maybe_uninit_ref", since = "1.55.0")]
-    #[rustc_const_unstable(feature = "const_maybe_uninit_assume_init", issue = "none")]
+    #[cfg_attr(bootstrap, rustc_allow_const_fn_unstable(const_mut_refs))]
+    #[rustc_const_stable(
+        feature = "const_maybe_uninit_assume_init",
+        since = "CURRENT_RUSTC_VERSION"
+    )]
     #[inline(always)]
     pub const unsafe fn assume_init_mut(&mut self) -> &mut T {
         // SAFETY: the caller must guarantee that `self` is initialized.
@@ -999,7 +1003,8 @@ impl<T> MaybeUninit<T> {
     ///
     /// [`assume_init_mut`]: MaybeUninit::assume_init_mut
     #[unstable(feature = "maybe_uninit_slice", issue = "63569")]
-    #[rustc_const_unstable(feature = "const_maybe_uninit_assume_init", issue = "none")]
+    #[cfg_attr(bootstrap, rustc_allow_const_fn_unstable(const_mut_refs))]
+    #[rustc_const_unstable(feature = "maybe_uninit_slice", issue = "63569")]
     #[inline(always)]
     pub const unsafe fn slice_assume_init_mut(slice: &mut [Self]) -> &mut [T] {
         // SAFETY: similar to safety notes for `slice_get_ref`, but we have a

library/core/src/net/ip_addr.rs

@@ -295,7 +295,6 @@ impl IpAddr {
     /// assert_eq!(IpAddr::V4(Ipv4Addr::new(80, 9, 12, 3)).is_global(), true);
     /// assert_eq!(IpAddr::V6(Ipv6Addr::new(0, 0, 0x1c9, 0, 0, 0xafc8, 0, 0x1)).is_global(), true);
     /// ```
-    #[rustc_const_unstable(feature = "const_ip", issue = "76205")]
     #[unstable(feature = "ip", issue = "27709")]
     #[must_use]
     #[inline]
@@ -348,7 +347,6 @@ impl IpAddr {
     ///     true
     /// );
     /// ```
-    #[rustc_const_unstable(feature = "const_ip", issue = "76205")]
     #[unstable(feature = "ip", issue = "27709")]
     #[must_use]
     #[inline]
@@ -600,6 +598,24 @@ impl Ipv4Addr {
         self.octets
     }
 
+    /// Creates an `Ipv4Addr` from a four element byte array.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(ip_from)]
+    /// use std::net::Ipv4Addr;
+    ///
+    /// let addr = Ipv4Addr::from_octets([13u8, 12u8, 11u8, 10u8]);
+    /// assert_eq!(Ipv4Addr::new(13, 12, 11, 10), addr);
+    /// ```
+    #[unstable(feature = "ip_from", issue = "131360")]
+    #[must_use]
+    #[inline]
+    pub const fn from_octets(octets: [u8; 4]) -> Ipv4Addr {
+        Ipv4Addr { octets }
+    }
+
     /// Returns [`true`] for the special 'unspecified' address (`0.0.0.0`).
     ///
     /// This property is defined in _UNIX Network Programming, Second Edition_,
@@ -776,7 +792,6 @@ impl Ipv4Addr {
     ///
     /// // For a complete overview see the IANA IPv4 Special-Purpose Address Registry.
     /// ```
-    #[rustc_const_unstable(feature = "const_ipv4", issue = "76205")]
     #[unstable(feature = "ip", issue = "27709")]
     #[must_use]
     #[inline]
@@ -813,7 +828,6 @@ impl Ipv4Addr {
     /// assert_eq!(Ipv4Addr::new(100, 127, 255, 255).is_shared(), true);
     /// assert_eq!(Ipv4Addr::new(100, 128, 0, 0).is_shared(), false);
     /// ```
-    #[rustc_const_unstable(feature = "const_ipv4", issue = "76205")]
     #[unstable(feature = "ip", issue = "27709")]
     #[must_use]
     #[inline]
@@ -841,7 +855,6 @@ impl Ipv4Addr {
     /// assert_eq!(Ipv4Addr::new(198, 19, 255, 255).is_benchmarking(), true);
     /// assert_eq!(Ipv4Addr::new(198, 20, 0, 0).is_benchmarking(), false);
     /// ```
-    #[rustc_const_unstable(feature = "const_ipv4", issue = "76205")]
     #[unstable(feature = "ip", issue = "27709")]
     #[must_use]
     #[inline]
@@ -878,7 +891,6 @@ impl Ipv4Addr {
     /// // The broadcast address is not considered as reserved for future use by this implementation
     /// assert_eq!(Ipv4Addr::new(255, 255, 255, 255).is_reserved(), false);
     /// ```
-    #[rustc_const_unstable(feature = "const_ipv4", issue = "76205")]
     #[unstable(feature = "ip", issue = "27709")]
     #[must_use]
     #[inline]
@@ -1400,6 +1412,34 @@ impl Ipv6Addr {
         ]
     }
 
+    /// Creates an `Ipv6Addr` from an eight element 16-bit array.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(ip_from)]
+    /// use std::net::Ipv6Addr;
+    ///
+    /// let addr = Ipv6Addr::from_segments([
+    ///     0x20du16, 0x20cu16, 0x20bu16, 0x20au16,
+    ///     0x209u16, 0x208u16, 0x207u16, 0x206u16,
+    /// ]);
+    /// assert_eq!(
+    ///     Ipv6Addr::new(
+    ///         0x20d, 0x20c, 0x20b, 0x20a,
+    ///         0x209, 0x208, 0x207, 0x206,
+    ///     ),
+    ///     addr
+    /// );
+    /// ```
+    #[unstable(feature = "ip_from", issue = "131360")]
+    #[must_use]
+    #[inline]
+    pub const fn from_segments(segments: [u16; 8]) -> Ipv6Addr {
+        let [a, b, c, d, e, f, g, h] = segments;
+        Ipv6Addr::new(a, b, c, d, e, f, g, h)
+    }
+
     /// Returns [`true`] for the special 'unspecified' address (`::`).
     ///
     /// This property is defined in [IETF RFC 4291].
@@ -1510,7 +1550,6 @@ impl Ipv6Addr {
     ///
     /// // For a complete overview see the IANA IPv6 Special-Purpose Address Registry.
     /// ```
-    #[rustc_const_unstable(feature = "const_ipv6", issue = "76205")]
     #[unstable(feature = "ip", issue = "27709")]
     #[must_use]
     #[inline]
@@ -1562,7 +1601,6 @@ impl Ipv6Addr {
     /// assert_eq!(Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0xc00a, 0x2ff).is_unique_local(), false);
     /// assert_eq!(Ipv6Addr::new(0xfc02, 0, 0, 0, 0, 0, 0, 0).is_unique_local(), true);
     /// ```
-    #[rustc_const_unstable(feature = "const_ipv6", issue = "76205")]
     #[unstable(feature = "ip", issue = "27709")]
     #[must_use]
     #[inline]
@@ -1591,7 +1629,6 @@ impl Ipv6Addr {
     /// assert_eq!(Ipv6Addr::new(0x2001, 0xdb8, 0, 0, 0, 0, 0, 0).is_unicast(), true);
     /// assert_eq!(Ipv6Addr::new(0xff00, 0, 0, 0, 0, 0, 0, 0).is_unicast(), false);
     /// ```
-    #[rustc_const_unstable(feature = "const_ipv6", issue = "76205")]
     #[unstable(feature = "ip", issue = "27709")]
     #[must_use]
     #[inline]
@@ -1643,7 +1680,6 @@ impl Ipv6Addr {
     /// assert_eq!(Ipv6Addr::new(0xfe80, 0, 0, 1, 0, 0, 0, 0).is_unicast_link_local(), true);
     /// assert_eq!(Ipv6Addr::new(0xfe81, 0, 0, 0, 0, 0, 0, 0).is_unicast_link_local(), true);
     /// ```
-    #[rustc_const_unstable(feature = "const_ipv6", issue = "76205")]
     #[unstable(feature = "ip", issue = "27709")]
     #[must_use]
     #[inline]
@@ -1668,7 +1704,6 @@ impl Ipv6Addr {
     /// assert_eq!(Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0xc00a, 0x2ff).is_documentation(), false);
     /// assert_eq!(Ipv6Addr::new(0x2001, 0xdb8, 0, 0, 0, 0, 0, 0).is_documentation(), true);
     /// ```
-    #[rustc_const_unstable(feature = "const_ipv6", issue = "76205")]
     #[unstable(feature = "ip", issue = "27709")]
     #[must_use]
     #[inline]
@@ -1729,7 +1764,6 @@ impl Ipv6Addr {
     /// assert_eq!(Ipv6Addr::new(0x2001, 0xdb8, 0, 0, 0, 0, 0, 0).is_unicast_global(), false);
     /// assert_eq!(Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0xc00a, 0x2ff).is_unicast_global(), true);
     /// ```
-    #[rustc_const_unstable(feature = "const_ipv6", issue = "76205")]
     #[unstable(feature = "ip", issue = "27709")]
     #[must_use]
     #[inline]
@@ -1758,7 +1792,6 @@ impl Ipv6Addr {
     /// );
     /// assert_eq!(Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0xc00a, 0x2ff).multicast_scope(), None);
     /// ```
-    #[rustc_const_unstable(feature = "const_ipv6", issue = "76205")]
     #[unstable(feature = "ip", issue = "27709")]
     #[must_use]
     #[inline]
@@ -1818,7 +1851,6 @@ impl Ipv6Addr {
     ///
     /// assert_eq!(Ipv6Addr::new(0x2001, 0xdb8, 0, 0, 0, 0, 0, 0).is_ipv4_mapped(), false);
     /// ```
-    #[rustc_const_unstable(feature = "const_ipv6", issue = "76205")]
     #[unstable(feature = "ip", issue = "27709")]
     #[must_use]
     #[inline]
@@ -1932,7 +1964,7 @@ impl Ipv6Addr {
     /// use std::net::Ipv6Addr;
     ///
     /// assert_eq!(Ipv6Addr::new(0xff00, 0, 0, 0, 0, 0, 0, 0).octets(),
-    ///            [255, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]);
+    ///            [0xff, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]);
     /// ```
     #[rustc_const_stable(feature = "const_ip_32", since = "1.32.0")]
     #[stable(feature = "ipv6_to_octets", since = "1.12.0")]
@@ -1941,6 +1973,33 @@ impl Ipv6Addr {
     pub const fn octets(&self) -> [u8; 16] {
         self.octets
     }
+
+    /// Creates an `Ipv6Addr` from a sixteen element byte array.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(ip_from)]
+    /// use std::net::Ipv6Addr;
+    ///
+    /// let addr = Ipv6Addr::from_octets([
+    ///     0x19u8, 0x18u8, 0x17u8, 0x16u8, 0x15u8, 0x14u8, 0x13u8, 0x12u8,
+    ///     0x11u8, 0x10u8, 0x0fu8, 0x0eu8, 0x0du8, 0x0cu8, 0x0bu8, 0x0au8,
+    /// ]);
+    /// assert_eq!(
+    ///     Ipv6Addr::new(
+    ///         0x1918, 0x1716, 0x1514, 0x1312,
+    ///         0x1110, 0x0f0e, 0x0d0c, 0x0b0a,
+    ///     ),
+    ///     addr
+    /// );
+    /// ```
+    #[unstable(feature = "ip_from", issue = "131360")]
+    #[must_use]
+    #[inline]
+    pub const fn from_octets(octets: [u8; 16]) -> Ipv6Addr {
+        Ipv6Addr { octets }
+    }
 }
 
 /// Writes an Ipv6Addr, conforming to the canonical style described by
@@ -2113,15 +2172,13 @@ impl From<[u8; 16]> for Ipv6Addr {
     /// use std::net::Ipv6Addr;
     ///
     /// let addr = Ipv6Addr::from([
-    ///     25u8, 24u8, 23u8, 22u8, 21u8, 20u8, 19u8, 18u8,
+    ///     0x19u8, 0x18u8, 0x17u8, 0x16u8, 0x15u8, 0x14u8, 0x13u8, 0x12u8,
-    ///     17u8, 16u8, 15u8, 14u8, 13u8, 12u8, 11u8, 10u8,
+    ///     0x11u8, 0x10u8, 0x0fu8, 0x0eu8, 0x0du8, 0x0cu8, 0x0bu8, 0x0au8,
     /// ]);
     /// assert_eq!(
     ///     Ipv6Addr::new(
-    ///         0x1918, 0x1716,
+    ///         0x1918, 0x1716, 0x1514, 0x1312,
-    ///         0x1514, 0x1312,
+    ///         0x1110, 0x0f0e, 0x0d0c, 0x0b0a,
-    ///         0x1110, 0x0f0e,
-    ///         0x0d0c, 0x0b0a
     ///     ),
     ///     addr
     /// );
@@ -2142,15 +2199,13 @@ impl From<[u16; 8]> for Ipv6Addr {
     /// use std::net::Ipv6Addr;
     ///
     /// let addr = Ipv6Addr::from([
-    ///     525u16, 524u16, 523u16, 522u16,
+    ///     0x20du16, 0x20cu16, 0x20bu16, 0x20au16,
-    ///     521u16, 520u16, 519u16, 518u16,
+    ///     0x209u16, 0x208u16, 0x207u16, 0x206u16,
     /// ]);
     /// assert_eq!(
     ///     Ipv6Addr::new(
-    ///         0x20d, 0x20c,
+    ///         0x20d, 0x20c, 0x20b, 0x20a,
-    ///         0x20b, 0x20a,
+    ///         0x209, 0x208, 0x207, 0x206,
-    ///         0x209, 0x208,
-    ///         0x207, 0x206
     ///     ),
     ///     addr
     /// );
@@ -2172,15 +2227,13 @@ impl From<[u8; 16]> for IpAddr {
     /// use std::net::{IpAddr, Ipv6Addr};
     ///
     /// let addr = IpAddr::from([
-    ///     25u8, 24u8, 23u8, 22u8, 21u8, 20u8, 19u8, 18u8,
+    ///     0x19u8, 0x18u8, 0x17u8, 0x16u8, 0x15u8, 0x14u8, 0x13u8, 0x12u8,
-    ///     17u8, 16u8, 15u8, 14u8, 13u8, 12u8, 11u8, 10u8,
+    ///     0x11u8, 0x10u8, 0x0fu8, 0x0eu8, 0x0du8, 0x0cu8, 0x0bu8, 0x0au8,
     /// ]);
     /// assert_eq!(
     ///     IpAddr::V6(Ipv6Addr::new(
-    ///         0x1918, 0x1716,
+    ///         0x1918, 0x1716, 0x1514, 0x1312,
-    ///         0x1514, 0x1312,
+    ///         0x1110, 0x0f0e, 0x0d0c, 0x0b0a,
-    ///         0x1110, 0x0f0e,
-    ///         0x0d0c, 0x0b0a
     ///     )),
     ///     addr
     /// );
@@ -2201,15 +2254,13 @@ impl From<[u16; 8]> for IpAddr {
     /// use std::net::{IpAddr, Ipv6Addr};
     ///
     /// let addr = IpAddr::from([
-    ///     525u16, 524u16, 523u16, 522u16,
+    ///     0x20du16, 0x20cu16, 0x20bu16, 0x20au16,
-    ///     521u16, 520u16, 519u16, 518u16,
+    ///     0x209u16, 0x208u16, 0x207u16, 0x206u16,
     /// ]);
     /// assert_eq!(
     ///     IpAddr::V6(Ipv6Addr::new(
-    ///         0x20d, 0x20c,
+    ///         0x20d, 0x20c, 0x20b, 0x20a,
-    ///         0x20b, 0x20a,
+    ///         0x209, 0x208, 0x207, 0x206,
-    ///         0x209, 0x208,
-    ///         0x207, 0x206
     ///     )),
     ///     addr
     /// );

library/core/tests/lib.rs

@@ -19,9 +19,6 @@
 #![feature(const_black_box)]
 #![feature(const_hash)]
 #![feature(const_heap)]
-#![feature(const_ip)]
-#![feature(const_ipv4)]
-#![feature(const_ipv6)]
 #![feature(const_likely)]
 #![feature(const_nonnull_new)]
 #![feature(const_option_ext)]
@@ -50,6 +47,7 @@
 #![feature(hashmap_internals)]
 #![feature(int_roundings)]
 #![feature(ip)]
+#![feature(ip_from)]
 #![feature(is_ascii_octdigit)]
 #![feature(isqrt)]
 #![feature(iter_advance_by)]

library/core/tests/net/ip_addr.rs

@@ -494,6 +494,7 @@ fn ipv6_properties() {
             let octets = &[$($octet),*];
             assert_eq!(&ip!($s).octets(), octets);
             assert_eq!(Ipv6Addr::from(*octets), ip!($s));
+            assert_eq!(Ipv6Addr::from_octets(*octets), ip!($s));
 
             let unspecified: u32 = 1 << 0;
             let loopback: u32 = 1 << 1;
@@ -846,15 +847,19 @@ fn ipv6_from_constructors() {
 
 #[test]
 fn ipv4_from_octets() {
-    assert_eq!(Ipv4Addr::from([127, 0, 0, 1]), Ipv4Addr::new(127, 0, 0, 1))
+    assert_eq!(Ipv4Addr::from([127, 0, 0, 1]), Ipv4Addr::new(127, 0, 0, 1));
+    assert_eq!(Ipv4Addr::from_octets([127, 0, 0, 1]), Ipv4Addr::new(127, 0, 0, 1));
 }
 
 #[test]
 fn ipv6_from_segments() {
     let from_u16s =
         Ipv6Addr::from([0x0011, 0x2233, 0x4455, 0x6677, 0x8899, 0xaabb, 0xccdd, 0xeeff]);
+    let from_u16s_explicit =
+        Ipv6Addr::from_segments([0x0011, 0x2233, 0x4455, 0x6677, 0x8899, 0xaabb, 0xccdd, 0xeeff]);
     let new = Ipv6Addr::new(0x0011, 0x2233, 0x4455, 0x6677, 0x8899, 0xaabb, 0xccdd, 0xeeff);
     assert_eq!(new, from_u16s);
+    assert_eq!(new, from_u16s_explicit);
 }
 
 #[test]
@@ -865,7 +870,15 @@ fn ipv6_from_octets() {
         0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88, 0x99, 0xaa, 0xbb, 0xcc, 0xdd, 0xee,
         0xff,
     ]);
+    let from_u16s_explicit =
+        Ipv6Addr::from_segments([0x0011, 0x2233, 0x4455, 0x6677, 0x8899, 0xaabb, 0xccdd, 0xeeff]);
+    let from_u8s_explicit = Ipv6Addr::from_octets([
+        0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88, 0x99, 0xaa, 0xbb, 0xcc, 0xdd, 0xee,
+        0xff,
+    ]);
     assert_eq!(from_u16s, from_u8s);
+    assert_eq!(from_u16s, from_u16s_explicit);
+    assert_eq!(from_u16s_explicit, from_u8s_explicit);
 }
 
 #[test]
@@ -915,6 +928,9 @@ fn ipv4_const() {
     const OCTETS: [u8; 4] = IP_ADDRESS.octets();
     assert_eq!(OCTETS, [127, 0, 0, 1]);
 
+    const FROM_OCTETS: Ipv4Addr = Ipv4Addr::from_octets(OCTETS);
+    assert_eq!(IP_ADDRESS, FROM_OCTETS);
+
     const IS_UNSPECIFIED: bool = IP_ADDRESS.is_unspecified();
     assert!(!IS_UNSPECIFIED);
 
@@ -971,9 +987,15 @@ fn ipv6_const() {
     const SEGMENTS: [u16; 8] = IP_ADDRESS.segments();
     assert_eq!(SEGMENTS, [0, 0, 0, 0, 0, 0, 0, 1]);
 
+    const FROM_SEGMENTS: Ipv6Addr = Ipv6Addr::from_segments(SEGMENTS);
+    assert_eq!(IP_ADDRESS, FROM_SEGMENTS);
+
     const OCTETS: [u8; 16] = IP_ADDRESS.octets();
     assert_eq!(OCTETS, [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1]);
 
+    const FROM_OCTETS: Ipv6Addr = Ipv6Addr::from_octets(OCTETS);
+    assert_eq!(IP_ADDRESS, FROM_OCTETS);
+
     const IS_UNSPECIFIED: bool = IP_ADDRESS.is_unspecified();
     assert!(!IS_UNSPECIFIED);
 

library/std/Cargo.toml

@@ -39,7 +39,7 @@ miniz_oxide = { version = "0.7.0", optional = true, default-features = false }
 addr2line = { version = "0.22.0", optional = true, default-features = false }
 
 [target.'cfg(not(all(windows, target_env = "msvc")))'.dependencies]
-libc = { version = "0.2.156", default-features = false, features = [
+libc = { version = "0.2.159", default-features = false, features = [
     'rustc-dep-of-std',
 ], public = true }
 

library/std/src/lib.rs

@@ -414,9 +414,6 @@
 // tidy-alphabetical-start
 #![feature(const_collections_with_hasher)]
 #![feature(const_hash)]
-#![feature(const_ip)]
-#![feature(const_ipv4)]
-#![feature(const_ipv6)]
 #![feature(thread_local_internals)]
 // tidy-alphabetical-end
 //

library/std/src/sys/pal/unix/fs.rs

@@ -1538,7 +1538,7 @@ impl fmt::Debug for File {
             Some(PathBuf::from(OsString::from_vec(buf)))
         }
 
-        #[cfg(all(target_os = "freebsd", target_arch = "x86_64"))]
+        #[cfg(target_os = "freebsd")]
         fn get_path(fd: c_int) -> Option<PathBuf> {
             let info = Box::<libc::kinfo_file>::new_zeroed();
             let mut info = unsafe { info.assume_init() };
@@ -1566,7 +1566,7 @@ impl fmt::Debug for File {
         #[cfg(not(any(
             target_os = "linux",
             target_os = "vxworks",
-            all(target_os = "freebsd", target_arch = "x86_64"),
+            target_os = "freebsd",
             target_os = "netbsd",
             target_os = "illumos",
             target_os = "solaris",

src/ci/docker/scripts/emscripten.sh

@@ -20,5 +20,5 @@ exit 1
 
 git clone https://github.com/emscripten-core/emsdk.git /emsdk-portable
 cd /emsdk-portable
-hide_output ./emsdk install 2.0.5
+hide_output ./emsdk install 3.1.68
-./emsdk activate 2.0.5
+./emsdk activate 3.1.68

src/tools/miri/src/diagnostics.rs

@@ -473,14 +473,14 @@ pub fn report_leaks<'tcx>(
     leaks: Vec<(AllocId, MemoryKind, Allocation<Provenance, AllocExtra<'tcx>, MiriAllocBytes>)>,
 ) {
     let mut any_pruned = false;
-    for (id, kind, mut alloc) in leaks {
+    for (id, kind, alloc) in leaks {
         let mut title = format!(
             "memory leaked: {id:?} ({}, size: {:?}, align: {:?})",
             kind,
             alloc.size().bytes(),
             alloc.align.bytes()
         );
-        let Some(backtrace) = alloc.extra.backtrace.take() else {
+        let Some(backtrace) = alloc.extra.backtrace else {
             ecx.tcx.dcx().err(title);
             continue;
         };

src/tools/miri/src/eval.rs

@@ -476,7 +476,7 @@ pub fn eval_entry<'tcx>(
         }
         // Check for memory leaks.
         info!("Additional static roots: {:?}", ecx.machine.static_roots);
-        let leaks = ecx.find_leaked_allocations(&ecx.machine.static_roots);
+        let leaks = ecx.take_leaked_allocations(|ecx| &ecx.machine.static_roots);
         if !leaks.is_empty() {
             report_leaks(&ecx, leaks);
             tcx.dcx().note("set `MIRIFLAGS=-Zmiri-ignore-leaks` to disable this check");

src/tools/miri/src/machine.rs

@@ -321,7 +321,7 @@ impl ProvenanceExtra {
 }
 
 /// Extra per-allocation data
-#[derive(Debug, Clone)]
+#[derive(Debug)]
 pub struct AllocExtra<'tcx> {
     /// Global state of the borrow tracker, if enabled.
     pub borrow_tracker: Option<borrow_tracker::AllocState>,
@@ -338,6 +338,14 @@ pub struct AllocExtra<'tcx> {
     pub backtrace: Option<Vec<FrameInfo<'tcx>>>,
 }
 
+// We need a `Clone` impl because the machine passes `Allocation` through `Cow`...
+// but that should never end up actually cloning our `AllocExtra`.
+impl<'tcx> Clone for AllocExtra<'tcx> {
+    fn clone(&self) -> Self {
+        panic!("our allocations should never be cloned");
+    }
+}
+
 impl VisitProvenance for AllocExtra<'_> {
     fn visit_provenance(&self, visit: &mut VisitWith<'_>) {
         let AllocExtra { borrow_tracker, data_race, weak_memory, backtrace: _ } = self;

tests/ui/lint/non-local-defs/convoluted-locals-131474-with-mods.rs

@@ -31,4 +31,15 @@ const _: () = {
     };
 };
 
+// https://github.com/rust-lang/rust/issues/131643
+const _: () = {
+    const _: () = {
+        impl tmp::InnerTest {}
+    };
+
+    mod tmp {
+        pub(super) struct InnerTest;
+    }
+};
+
 fn main() {}

tests/ui/lint/non-local-defs/convoluted-locals-131474.rs

@@ -21,4 +21,13 @@ const _: () = {
     };
 };
 
+// https://github.com/rust-lang/rust/issues/131643
+const _: () = {
+    const _: () = {
+        impl InnerTest {}
+    };
+
+    struct InnerTest;
+};
+
 fn main() {}