Auto merge of #138414 - matthiaskrgr:rollup-9ablqdb, r=matthiaskrgr

Rollup of 7 pull requests

Successful merges:

 - #137314 (change definitely unproductive cycles to error)
 - #137701 (Convert `ShardedHashMap` to use `hashbrown::HashTable`)
 - #138269 (uefi: fs: Implement FileType, FilePermissions and FileAttr)
 - #138331 (Use `RUSTC_LINT_FLAGS` more)
 - #138345 (Some autodiff cleanups)
 - #138387 (intrinsics: remove unnecessary leading underscore from argument names)
 - #138390 (fix incorrect tracing log)

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

Cargo.lock

@@ -1491,6 +1491,7 @@ version = "0.15.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bf151400ff0baff5465007dd2f3e717f3fe502074ca563069ce3a6629d07b289"
 dependencies = [
+ "allocator-api2",
  "foldhash",
  "serde",
 ]
@@ -3492,6 +3493,7 @@ dependencies = [
  "either",
  "elsa",
  "ena",
+ "hashbrown 0.15.2",
  "indexmap",
  "jobserver",
  "libc",

compiler/rustc_abi/src/lib.rs

@@ -5,7 +5,6 @@
 #![cfg_attr(feature = "nightly", feature(rustc_attrs))]
 #![cfg_attr(feature = "nightly", feature(rustdoc_internals))]
 #![cfg_attr(feature = "nightly", feature(step_trait))]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 /*! ABI handling for rustc

compiler/rustc_arena/src/lib.rs

@@ -23,7 +23,6 @@
 #![feature(maybe_uninit_slice)]
 #![feature(rustc_attrs)]
 #![feature(rustdoc_internals)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 use std::alloc::Layout;

compiler/rustc_ast/src/lib.rs

@@ -20,7 +20,6 @@
 #![feature(never_type)]
 #![feature(rustdoc_internals)]
 #![feature(stmt_expr_attributes)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 pub mod util {

compiler/rustc_ast_ir/src/lib.rs

@@ -9,7 +9,6 @@
 #![cfg_attr(feature = "nightly", allow(internal_features))]
 #![cfg_attr(feature = "nightly", feature(never_type))]
 #![cfg_attr(feature = "nightly", feature(rustc_attrs))]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 #[cfg(feature = "nightly")]

compiler/rustc_ast_lowering/src/lib.rs

@@ -40,7 +40,6 @@
 #![feature(if_let_guard)]
 #![feature(let_chains)]
 #![feature(rustdoc_internals)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 use std::sync::Arc;

compiler/rustc_ast_passes/src/lib.rs

@@ -10,7 +10,6 @@
 #![feature(iter_is_partitioned)]
 #![feature(let_chains)]
 #![feature(rustdoc_internals)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 pub mod ast_validation;

compiler/rustc_ast_pretty/src/lib.rs

@@ -3,7 +3,6 @@
 #![doc(rust_logo)]
 #![feature(box_patterns)]
 #![feature(rustdoc_internals)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 mod helpers;

compiler/rustc_attr_data_structures/src/lib.rs

@@ -3,7 +3,6 @@
 #![doc(rust_logo)]
 #![feature(let_chains)]
 #![feature(rustdoc_internals)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 mod attributes;

compiler/rustc_attr_parsing/src/lib.rs

@@ -81,7 +81,6 @@
 #![doc(rust_logo)]
 #![feature(let_chains)]
 #![feature(rustdoc_internals)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 #[macro_use]

compiler/rustc_baked_icu_data/src/lib.rs

@@ -23,6 +23,7 @@
 // tidy-alphabetical-start
 #![allow(elided_lifetimes_in_paths)]
 #![allow(internal_features)]
+#![allow(unreachable_pub)] // because this crate is mostly generated code
 #![doc(rust_logo)]
 #![feature(rustdoc_internals)]
 // #![warn(unreachable_pub)] // don't use because this crate is mostly generated code

compiler/rustc_borrowck/src/lib.rs

@@ -14,7 +14,6 @@
 #![feature(rustdoc_internals)]
 #![feature(stmt_expr_attributes)]
 #![feature(try_blocks)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 use std::borrow::Cow;

compiler/rustc_builtin_macros/src/lib.rs

@@ -19,7 +19,6 @@
 #![feature(rustdoc_internals)]
 #![feature(string_from_utf8_lossy_owned)]
 #![feature(try_blocks)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 extern crate proc_macro;

compiler/rustc_codegen_cranelift/example/mini_core.rs

@@ -624,25 +624,25 @@ pub mod intrinsics {
     #[rustc_intrinsic]
     pub fn size_of<T>() -> usize;
     #[rustc_intrinsic]
-    pub unsafe fn size_of_val<T: ?::Sized>(_val: *const T) -> usize;
+    pub unsafe fn size_of_val<T: ?::Sized>(val: *const T) -> usize;
     #[rustc_intrinsic]
     pub fn min_align_of<T>() -> usize;
     #[rustc_intrinsic]
-    pub unsafe fn min_align_of_val<T: ?::Sized>(_val: *const T) -> usize;
+    pub unsafe fn min_align_of_val<T: ?::Sized>(val: *const T) -> usize;
     #[rustc_intrinsic]
-    pub unsafe fn copy<T>(_src: *const T, _dst: *mut T, _count: usize);
+    pub unsafe fn copy<T>(src: *const T, dst: *mut T, count: usize);
     #[rustc_intrinsic]
-    pub unsafe fn transmute<T, U>(_e: T) -> U;
+    pub unsafe fn transmute<T, U>(e: T) -> U;
     #[rustc_intrinsic]
-    pub unsafe fn ctlz_nonzero<T>(_x: T) -> u32;
+    pub unsafe fn ctlz_nonzero<T>(x: T) -> u32;
     #[rustc_intrinsic]
     pub fn needs_drop<T: ?::Sized>() -> bool;
     #[rustc_intrinsic]
-    pub fn bitreverse<T>(_x: T) -> T;
+    pub fn bitreverse<T>(x: T) -> T;
     #[rustc_intrinsic]
-    pub fn bswap<T>(_x: T) -> T;
+    pub fn bswap<T>(x: T) -> T;
     #[rustc_intrinsic]
-    pub unsafe fn write_bytes<T>(_dst: *mut T, _val: u8, _count: usize);
+    pub unsafe fn write_bytes<T>(dst: *mut T, val: u8, count: usize);
     #[rustc_intrinsic]
     pub unsafe fn unreachable() -> !;
 }

compiler/rustc_codegen_gcc/example/mini_core.rs

@@ -595,25 +595,25 @@ pub mod intrinsics {
     #[rustc_intrinsic]
     pub fn size_of<T>() -> usize;
     #[rustc_intrinsic]
-    pub unsafe fn size_of_val<T: ?::Sized>(_val: *const T) -> usize;
+    pub unsafe fn size_of_val<T: ?::Sized>(val: *const T) -> usize;
     #[rustc_intrinsic]
     pub fn min_align_of<T>() -> usize;
     #[rustc_intrinsic]
-    pub unsafe fn min_align_of_val<T: ?::Sized>(_val: *const T) -> usize;
+    pub unsafe fn min_align_of_val<T: ?::Sized>(val: *const T) -> usize;
     #[rustc_intrinsic]
-    pub unsafe fn copy<T>(_src: *const T, _dst: *mut T, _count: usize);
+    pub unsafe fn copy<T>(src: *const T, dst: *mut T, count: usize);
     #[rustc_intrinsic]
-    pub unsafe fn transmute<T, U>(_e: T) -> U;
+    pub unsafe fn transmute<T, U>(e: T) -> U;
     #[rustc_intrinsic]
-    pub unsafe fn ctlz_nonzero<T>(_x: T) -> u32;
+    pub unsafe fn ctlz_nonzero<T>(x: T) -> u32;
     #[rustc_intrinsic]
     pub fn needs_drop<T: ?::Sized>() -> bool;
     #[rustc_intrinsic]
-    pub fn bitreverse<T>(_x: T) -> T;
+    pub fn bitreverse<T>(x: T) -> T;
     #[rustc_intrinsic]
-    pub fn bswap<T>(_x: T) -> T;
+    pub fn bswap<T>(x: T) -> T;
     #[rustc_intrinsic]
-    pub unsafe fn write_bytes<T>(_dst: *mut T, _val: u8, _count: usize);
+    pub unsafe fn write_bytes<T>(dst: *mut T, val: u8, count: usize);
     #[rustc_intrinsic]
     pub unsafe fn unreachable() -> !;
 }

compiler/rustc_codegen_llvm/src/lib.rs

@@ -19,7 +19,6 @@
 #![feature(rustdoc_internals)]
 #![feature(slice_as_array)]
 #![feature(try_blocks)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 use std::any::Any;

compiler/rustc_codegen_ssa/src/lib.rs

@@ -15,7 +15,6 @@
 #![feature(rustdoc_internals)]
 #![feature(trait_alias)]
 #![feature(try_blocks)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 //! This crate contains codegen code that is used by all codegen backends (LLVM and others).

compiler/rustc_const_eval/src/lib.rs

@@ -17,7 +17,6 @@
 #![feature(unqualified_local_imports)]
 #![feature(yeet_expr)]
 #![warn(unqualified_local_imports)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 pub mod check_consts;

compiler/rustc_data_structures/Cargo.toml

@@ -29,6 +29,11 @@ thin-vec = "0.2.12"
 tracing = "0.1"
 # tidy-alphabetical-end
 
+[dependencies.hashbrown]
+version = "0.15.2"
+default-features = false
+features = ["nightly"] # for may_dangle
+
 [dependencies.parking_lot]
 version = "0.12"
 

compiler/rustc_data_structures/src/graph/tests.rs

@@ -3,7 +3,7 @@ use std::cmp::max;
 use super::*;
 use crate::fx::FxHashMap;
 
-pub struct TestGraph {
+pub(super) struct TestGraph {
     num_nodes: usize,
     start_node: usize,
     successors: FxHashMap<usize, Vec<usize>>,
@@ -11,7 +11,7 @@ pub struct TestGraph {
 }
 
 impl TestGraph {
-    pub fn new(start_node: usize, edges: &[(usize, usize)]) -> Self {
+    pub(super) fn new(start_node: usize, edges: &[(usize, usize)]) -> Self {
         let mut graph = TestGraph {
             num_nodes: start_node + 1,
             start_node,

compiler/rustc_data_structures/src/lib.rs

@@ -24,7 +24,6 @@
 #![feature(dropck_eyepatch)]
 #![feature(extend_one)]
 #![feature(file_buffered)]
-#![feature(hash_raw_entry)]
 #![feature(macro_metavar_expr)]
 #![feature(map_try_insert)]
 #![feature(min_specialization)]

compiler/rustc_data_structures/src/marker.rs

@@ -76,6 +76,7 @@ impl_dyn_send!(
     [crate::sync::RwLock<T> where T: DynSend]
     [crate::tagged_ptr::TaggedRef<'a, P, T> where 'a, P: Sync, T: Send + crate::tagged_ptr::Tag]
     [rustc_arena::TypedArena<T> where T: DynSend]
+    [hashbrown::HashTable<T> where T: DynSend]
     [indexmap::IndexSet<V, S> where V: DynSend, S: DynSend]
     [indexmap::IndexMap<K, V, S> where K: DynSend, V: DynSend, S: DynSend]
     [thin_vec::ThinVec<T> where T: DynSend]
@@ -153,6 +154,7 @@ impl_dyn_sync!(
     [crate::tagged_ptr::TaggedRef<'a, P, T> where 'a, P: Sync, T: Sync + crate::tagged_ptr::Tag]
     [parking_lot::lock_api::Mutex<R, T> where R: DynSync, T: ?Sized + DynSend]
     [parking_lot::lock_api::RwLock<R, T> where R: DynSync, T: ?Sized + DynSend + DynSync]
+    [hashbrown::HashTable<T> where T: DynSync]
     [indexmap::IndexSet<V, S> where V: DynSync, S: DynSync]
     [indexmap::IndexMap<K, V, S> where K: DynSync, V: DynSync, S: DynSync]
     [smallvec::SmallVec<A> where A: smallvec::Array + DynSync]

compiler/rustc_data_structures/src/obligation_forest/mod.rs

@@ -313,7 +313,7 @@ pub struct Error<O, E> {
 
 mod helper {
     use super::*;
-    pub type ObligationTreeIdGenerator = impl Iterator<Item = ObligationTreeId>;
+    pub(super) type ObligationTreeIdGenerator = impl Iterator<Item = ObligationTreeId>;
     impl<O: ForestObligation> ObligationForest<O> {
         #[cfg_attr(not(bootstrap), define_opaque(ObligationTreeIdGenerator))]
         pub fn new() -> ObligationForest<O> {

compiler/rustc_data_structures/src/sharded.rs

@@ -1,11 +1,11 @@
 use std::borrow::Borrow;
-use std::collections::hash_map::RawEntryMut;
 use std::hash::{Hash, Hasher};
-use std::iter;
+use std::{iter, mem};
 
 use either::Either;
+use hashbrown::hash_table::{Entry, HashTable};
 
-use crate::fx::{FxHashMap, FxHasher};
+use crate::fx::FxHasher;
 use crate::sync::{CacheAligned, Lock, LockGuard, Mode, is_dyn_thread_safe};
 
 // 32 shards is sufficient to reduce contention on an 8-core Ryzen 7 1700,
@@ -140,17 +140,67 @@ pub fn shards() -> usize {
     1
 }
 
-pub type ShardedHashMap<K, V> = Sharded<FxHashMap<K, V>>;
+pub type ShardedHashMap<K, V> = Sharded<HashTable<(K, V)>>;
 
 impl<K: Eq, V> ShardedHashMap<K, V> {
     pub fn with_capacity(cap: usize) -> Self {
-        Self::new(|| FxHashMap::with_capacity_and_hasher(cap, rustc_hash::FxBuildHasher::default()))
+        Self::new(|| HashTable::with_capacity(cap))
     }
     pub fn len(&self) -> usize {
         self.lock_shards().map(|shard| shard.len()).sum()
     }
 }
 
+impl<K: Eq + Hash, V> ShardedHashMap<K, V> {
+    #[inline]
+    pub fn get<Q>(&self, key: &Q) -> Option<V>
+    where
+        K: Borrow<Q>,
+        Q: Hash + Eq,
+        V: Clone,
+    {
+        let hash = make_hash(key);
+        let shard = self.lock_shard_by_hash(hash);
+        let (_, value) = shard.find(hash, |(k, _)| k.borrow() == key)?;
+        Some(value.clone())
+    }
+
+    #[inline]
+    pub fn get_or_insert_with(&self, key: K, default: impl FnOnce() -> V) -> V
+    where
+        V: Copy,
+    {
+        let hash = make_hash(&key);
+        let mut shard = self.lock_shard_by_hash(hash);
+
+        match table_entry(&mut shard, hash, &key) {
+            Entry::Occupied(e) => e.get().1,
+            Entry::Vacant(e) => {
+                let value = default();
+                e.insert((key, value));
+                value
+            }
+        }
+    }
+
+    #[inline]
+    pub fn insert(&self, key: K, value: V) -> Option<V> {
+        let hash = make_hash(&key);
+        let mut shard = self.lock_shard_by_hash(hash);
+
+        match table_entry(&mut shard, hash, &key) {
+            Entry::Occupied(e) => {
+                let previous = mem::replace(&mut e.into_mut().1, value);
+                Some(previous)
+            }
+            Entry::Vacant(e) => {
+                e.insert((key, value));
+                None
+            }
+        }
+    }
+}
+
 impl<K: Eq + Hash + Copy> ShardedHashMap<K, ()> {
     #[inline]
     pub fn intern_ref<Q: ?Sized>(&self, value: &Q, make: impl FnOnce() -> K) -> K
@@ -160,13 +210,12 @@ impl<K: Eq + Hash + Copy> ShardedHashMap<K, ()> {
     {
         let hash = make_hash(value);
         let mut shard = self.lock_shard_by_hash(hash);
-        let entry = shard.raw_entry_mut().from_key_hashed_nocheck(hash, value);
 
-        match entry {
+        match table_entry(&mut shard, hash, value) {
-            RawEntryMut::Occupied(e) => *e.key(),
+            Entry::Occupied(e) => e.get().0,
-            RawEntryMut::Vacant(e) => {
+            Entry::Vacant(e) => {
                 let v = make();
-                e.insert_hashed_nocheck(hash, v, ());
+                e.insert((v, ()));
                 v
             }
         }
@@ -180,13 +229,12 @@ impl<K: Eq + Hash + Copy> ShardedHashMap<K, ()> {
     {
         let hash = make_hash(&value);
         let mut shard = self.lock_shard_by_hash(hash);
-        let entry = shard.raw_entry_mut().from_key_hashed_nocheck(hash, &value);
 
-        match entry {
+        match table_entry(&mut shard, hash, &value) {
-            RawEntryMut::Occupied(e) => *e.key(),
+            Entry::Occupied(e) => e.get().0,
-            RawEntryMut::Vacant(e) => {
+            Entry::Vacant(e) => {
                 let v = make(value);
-                e.insert_hashed_nocheck(hash, v, ());
+                e.insert((v, ()));
                 v
             }
         }
@@ -203,17 +251,30 @@ impl<K: Eq + Hash + Copy + IntoPointer> ShardedHashMap<K, ()> {
         let hash = make_hash(&value);
         let shard = self.lock_shard_by_hash(hash);
         let value = value.into_pointer();
-        shard.raw_entry().from_hash(hash, |entry| entry.into_pointer() == value).is_some()
+        shard.find(hash, |(k, ())| k.into_pointer() == value).is_some()
     }
 }
 
 #[inline]
-pub fn make_hash<K: Hash + ?Sized>(val: &K) -> u64 {
+fn make_hash<K: Hash + ?Sized>(val: &K) -> u64 {
     let mut state = FxHasher::default();
     val.hash(&mut state);
     state.finish()
 }
 
+#[inline]
+fn table_entry<'a, K, V, Q>(
+    table: &'a mut HashTable<(K, V)>,
+    hash: u64,
+    key: &Q,
+) -> Entry<'a, (K, V)>
+where
+    K: Hash + Borrow<Q>,
+    Q: ?Sized + Eq,
+{
+    table.entry(hash, move |(k, _)| k.borrow() == key, |(k, _)| make_hash(k))
+}
+
 /// Get a shard with a pre-computed hash value. If `get_shard_by_value` is
 /// ever used in combination with `get_shard_by_hash` on a single `Sharded`
 /// instance, then `hash` must be computed with `FxHasher`. Otherwise,

compiler/rustc_data_structures/src/sync.rs

@@ -88,7 +88,7 @@ mod mode {
 
     // Whether thread safety might be enabled.
     #[inline]
-    pub fn might_be_dyn_thread_safe() -> bool {
+    pub(super) fn might_be_dyn_thread_safe() -> bool {
         DYN_THREAD_SAFE_MODE.load(Ordering::Relaxed) != DYN_NOT_THREAD_SAFE
     }
 

compiler/rustc_data_structures/src/sync/parallel.rs

@@ -46,7 +46,7 @@ pub fn parallel_guard<R>(f: impl FnOnce(&ParallelGuard) -> R) -> R {
     ret
 }
 
-pub fn serial_join<A, B, RA, RB>(oper_a: A, oper_b: B) -> (RA, RB)
+fn serial_join<A, B, RA, RB>(oper_a: A, oper_b: B) -> (RA, RB)
 where
     A: FnOnce() -> RA,
     B: FnOnce() -> RB,

compiler/rustc_data_structures/src/tagged_ptr/tests.rs

@@ -7,7 +7,7 @@ use crate::stable_hasher::{HashStable, StableHasher};
 
 /// A tag type used in [`TaggedRef`] tests.
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
-pub enum Tag2 {
+enum Tag2 {
     B00 = 0b00,
     B01 = 0b01,
     B10 = 0b10,

compiler/rustc_driver_impl/src/lib.rs

@@ -17,7 +17,6 @@
 #![feature(result_flattening)]
 #![feature(rustdoc_internals)]
 #![feature(try_blocks)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 use std::cmp::max;

compiler/rustc_error_codes/src/lib.rs

@@ -6,7 +6,6 @@
 #![deny(rustdoc::invalid_codeblock_attributes)]
 #![doc(rust_logo)]
 #![feature(rustdoc_internals)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 // This higher-order macro defines the error codes that are in use. It is used

compiler/rustc_error_messages/src/lib.rs

@@ -4,7 +4,6 @@
 #![feature(rustc_attrs)]
 #![feature(rustdoc_internals)]
 #![feature(type_alias_impl_trait)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 use std::borrow::Cow;

compiler/rustc_errors/src/lib.rs

@@ -25,7 +25,6 @@
 #![feature(trait_alias)]
 #![feature(try_blocks)]
 #![feature(yeet_expr)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 extern crate self as rustc_errors;

compiler/rustc_expand/src/lib.rs

@@ -13,7 +13,6 @@
 #![feature(rustdoc_internals)]
 #![feature(try_blocks)]
 #![feature(yeet_expr)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 extern crate proc_macro as pm;

compiler/rustc_feature/src/lib.rs

@@ -15,7 +15,6 @@
 #![allow(internal_features)]
 #![doc(rust_logo)]
 #![feature(rustdoc_internals)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 mod accepted;

compiler/rustc_fluent_macro/src/lib.rs

@@ -7,7 +7,6 @@
 #![feature(proc_macro_span)]
 #![feature(rustdoc_internals)]
 #![feature(track_path)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 use proc_macro::TokenStream;

compiler/rustc_graphviz/src/lib.rs

@@ -277,7 +277,6 @@
 )]
 #![doc(rust_logo)]
 #![feature(rustdoc_internals)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 use std::borrow::Cow;

compiler/rustc_hir/src/lib.rs

@@ -14,7 +14,6 @@
 #![feature(never_type)]
 #![feature(rustc_attrs)]
 #![feature(variant_count)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 extern crate self as rustc_hir;

compiler/rustc_hir_analysis/src/lib.rs

@@ -74,7 +74,6 @@ This API is completely unstable and subject to change.
 #![feature(slice_partition_dedup)]
 #![feature(try_blocks)]
 #![feature(unwrap_infallible)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 // These are used by Clippy.

compiler/rustc_hir_pretty/src/lib.rs

@@ -3,7 +3,6 @@
 
 // tidy-alphabetical-start
 #![recursion_limit = "256"]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 use std::cell::Cell;

compiler/rustc_hir_typeck/src/lib.rs

@@ -9,7 +9,6 @@
 #![feature(let_chains)]
 #![feature(never_type)]
 #![feature(try_blocks)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 mod _match;

compiler/rustc_incremental/src/lib.rs

@@ -8,7 +8,6 @@
 #![doc(rust_logo)]
 #![feature(file_buffered)]
 #![feature(rustdoc_internals)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 mod assert_dep_graph;

compiler/rustc_index/src/lib.rs

@@ -4,7 +4,6 @@
 #![cfg_attr(feature = "nightly", feature(extend_one, step_trait, test))]
 #![cfg_attr(feature = "nightly", feature(new_range_api))]
 #![cfg_attr(feature = "nightly", feature(new_zeroed_alloc))]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 pub mod bit_set;

compiler/rustc_index_macros/src/newtype.rs

@@ -305,7 +305,7 @@ impl Parse for Newtype {
     }
 }
 
-pub fn newtype(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
+pub(crate) fn newtype(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
     let input = parse_macro_input!(input as Newtype);
     input.0.into()
 }

compiler/rustc_infer/src/lib.rs

@@ -24,7 +24,6 @@
 #![feature(let_chains)]
 #![feature(rustdoc_internals)]
 #![recursion_limit = "512"] // For rustdoc
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 mod errors;

compiler/rustc_interface/src/lib.rs

@@ -4,7 +4,6 @@
 #![feature(iter_intersperse)]
 #![feature(let_chains)]
 #![feature(try_blocks)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 mod callbacks;

compiler/rustc_lexer/src/lib.rs

@@ -23,7 +23,6 @@
 // We want to be able to build this crate with a stable compiler,
 // so no `#![feature]` attributes should be added.
 #![deny(unstable_features)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 mod cursor;

compiler/rustc_lint/src/lib.rs

@@ -33,7 +33,6 @@
 #![feature(rustc_attrs)]
 #![feature(rustdoc_internals)]
 #![feature(try_blocks)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 mod async_closures;

compiler/rustc_lint_defs/src/lib.rs

@@ -1,7 +1,3 @@
-// tidy-alphabetical-start
-#![warn(unreachable_pub)]
-// tidy-alphabetical-end
-
 use rustc_abi::ExternAbi;
 use rustc_ast::AttrId;
 use rustc_ast::attr::AttributeExt;

compiler/rustc_llvm/src/lib.rs

@@ -4,7 +4,6 @@
 #![doc(rust_logo)]
 #![feature(extern_types)]
 #![feature(rustdoc_internals)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 use std::cell::RefCell;

compiler/rustc_macros/src/lib.rs

@@ -6,7 +6,6 @@
 #![feature(proc_macro_diagnostic)]
 #![feature(proc_macro_span)]
 #![feature(proc_macro_tracked_env)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 use proc_macro::TokenStream;

compiler/rustc_metadata/src/lib.rs

@@ -16,7 +16,6 @@
 #![feature(proc_macro_internals)]
 #![feature(rustdoc_internals)]
 #![feature(trusted_len)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 extern crate proc_macro;

compiler/rustc_middle/src/lib.rs

@@ -62,7 +62,6 @@
 #![feature(try_trait_v2_yeet)]
 #![feature(type_alias_impl_trait)]
 #![feature(yeet_expr)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 #[cfg(test)]

compiler/rustc_middle/src/mir/interpret/mod.rs

@@ -452,12 +452,7 @@ impl<'tcx> TyCtxt<'tcx> {
         }
         let id = self.alloc_map.reserve();
         debug!("creating alloc {:?} with id {id:?}", alloc_salt.0);
-        let had_previous = self
+        let had_previous = self.alloc_map.to_alloc.insert(id, alloc_salt.0.clone()).is_some();
-            .alloc_map
-            .to_alloc
-            .lock_shard_by_value(&id)
-            .insert(id, alloc_salt.0.clone())
-            .is_some();
         // We just reserved, so should always be unique.
         assert!(!had_previous);
         dedup.insert(alloc_salt, id);
@@ -510,7 +505,7 @@ impl<'tcx> TyCtxt<'tcx> {
     /// local dangling pointers and allocations in constants/statics.
     #[inline]
     pub fn try_get_global_alloc(self, id: AllocId) -> Option<GlobalAlloc<'tcx>> {
-        self.alloc_map.to_alloc.lock_shard_by_value(&id).get(&id).cloned()
+        self.alloc_map.to_alloc.get(&id)
     }
 
     #[inline]
@@ -529,9 +524,7 @@ impl<'tcx> TyCtxt<'tcx> {
     /// Freezes an `AllocId` created with `reserve` by pointing it at an `Allocation`. Trying to
     /// call this function twice, even with the same `Allocation` will ICE the compiler.
     pub fn set_alloc_id_memory(self, id: AllocId, mem: ConstAllocation<'tcx>) {
-        if let Some(old) =
+        if let Some(old) = self.alloc_map.to_alloc.insert(id, GlobalAlloc::Memory(mem)) {
-            self.alloc_map.to_alloc.lock_shard_by_value(&id).insert(id, GlobalAlloc::Memory(mem))
-        {
             bug!("tried to set allocation ID {id:?}, but it was already existing as {old:#?}");
         }
     }
@@ -539,11 +532,8 @@ impl<'tcx> TyCtxt<'tcx> {
     /// Freezes an `AllocId` created with `reserve` by pointing it at a static item. Trying to
     /// call this function twice, even with the same `DefId` will ICE the compiler.
     pub fn set_nested_alloc_id_static(self, id: AllocId, def_id: LocalDefId) {
-        if let Some(old) = self
+        if let Some(old) =
-            .alloc_map
+            self.alloc_map.to_alloc.insert(id, GlobalAlloc::Static(def_id.to_def_id()))
-            .to_alloc
-            .lock_shard_by_value(&id)
-            .insert(id, GlobalAlloc::Static(def_id.to_def_id()))
         {
             bug!("tried to set allocation ID {id:?}, but it was already existing as {old:#?}");
         }

compiler/rustc_middle/src/ty/context.rs

@@ -2336,8 +2336,8 @@ macro_rules! sty_debug_print {
                 $(let mut $variant = total;)*
 
                 for shard in tcx.interners.type_.lock_shards() {
-                    let types = shard.keys();
+                    let types = shard.iter();
-                    for &InternedInSet(t) in types {
+                    for &(InternedInSet(t), ()) in types {
                         let variant = match t.internee {
                             ty::Bool | ty::Char | ty::Int(..) | ty::Uint(..) |
                                 ty::Float(..) | ty::Str | ty::Never => continue,

compiler/rustc_mir_build/src/lib.rs

@@ -9,7 +9,6 @@
 #![feature(if_let_guard)]
 #![feature(let_chains)]
 #![feature(try_blocks)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 // The `builder` module used to be named `build`, but that was causing GitHub's

compiler/rustc_mir_dataflow/src/lib.rs

@@ -8,7 +8,6 @@
 #![feature(let_chains)]
 #![feature(never_type)]
 #![feature(try_blocks)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 use rustc_middle::ty;

compiler/rustc_mir_transform/src/lib.rs

@@ -13,7 +13,6 @@
 #![feature(never_type)]
 #![feature(try_blocks)]
 #![feature(yeet_expr)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 use hir::ConstContext;

compiler/rustc_monomorphize/src/lib.rs

@@ -5,7 +5,6 @@
 #![feature(if_let_guard)]
 #![feature(impl_trait_in_assoc_type)]
 #![feature(let_chains)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 use rustc_hir::lang_items::LangItem;

compiler/rustc_monomorphize/src/partitioning/autodiff.rs

@@ -12,21 +12,15 @@ fn adjust_activity_to_abi<'tcx>(tcx: TyCtxt<'tcx>, fn_ty: Ty<'tcx>, da: &mut Vec
     if !matches!(fn_ty.kind(), ty::FnDef(..)) {
         bug!("expected fn def for autodiff, got {:?}", fn_ty);
     }
-    let fnc_binder: ty::Binder<'_, ty::FnSig<'_>> = fn_ty.fn_sig(tcx);
 
-    // If rustc compiles the unmodified primal, we know that this copy of the function
+    // We don't actually pass the types back into the type system.
-    // also has correct lifetimes. We know that Enzyme won't free the shadow too early
+    // All we do is decide how to handle the arguments.
-    // (or actually at all), so let's strip lifetimes when computing the layout.
+    let sig = fn_ty.fn_sig(tcx).skip_binder();
-    let x = tcx.instantiate_bound_regions_with_erased(fnc_binder);
+
     let mut new_activities = vec![];
     let mut new_positions = vec![];
-    for (i, ty) in x.inputs().iter().enumerate() {
+    for (i, ty) in sig.inputs().iter().enumerate() {
         if let Some(inner_ty) = ty.builtin_deref(true) {
-            if ty.is_fn_ptr() {
-                // FIXME(ZuseZ4): add a nicer error, or just figure out how to support them,
-                // since Enzyme itself can handle them.
-                tcx.dcx().err("function pointers are currently not supported in autodiff");
-            }
             if inner_ty.is_slice() {
                 // We know that the length will be passed as extra arg.
                 if !da.is_empty() {

compiler/rustc_next_trait_solver/src/lib.rs

@@ -6,7 +6,6 @@
 
 // tidy-alphabetical-start
 #![allow(rustc::usage_of_type_ir_inherent)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 pub mod canonicalizer;

compiler/rustc_next_trait_solver/src/solve/eval_ctxt/mod.rs

@@ -271,12 +271,39 @@ where
     /// and will need to clearly document it in the rustc-dev-guide before
     /// stabilization.
     pub(super) fn step_kind_for_source(&self, source: GoalSource) -> PathKind {
-        match (self.current_goal_kind, source) {
+        match source {
-            (_, GoalSource::NormalizeGoal(step_kind)) => step_kind,
+            // We treat these goals as unknown for now. It is likely that most miscellaneous
-            (CurrentGoalKind::CoinductiveTrait, GoalSource::ImplWhereBound) => {
+            // nested goals will be converted to an inductive variant in the future.
+            //
+            // Having unknown cycles is always the safer option, as changing that to either
+            // succeed or hard error is backwards compatible. If we incorrectly treat a cycle
+            // as inductive even though it should not be, it may be unsound during coherence and
+            // fixing it may cause inference breakage or introduce ambiguity.
+            GoalSource::Misc => PathKind::Unknown,
+            GoalSource::NormalizeGoal(path_kind) => path_kind,
+            GoalSource::ImplWhereBound => {
+                // We currently only consider a cycle coinductive if it steps
+                // into a where-clause of a coinductive trait.
+                //
+                // We probably want to make all traits coinductive in the future,
+                // so we treat cycles involving their where-clauses as ambiguous.
+                if let CurrentGoalKind::CoinductiveTrait = self.current_goal_kind {
                     PathKind::Coinductive
+                } else {
+                    PathKind::Unknown
                 }
-            _ => PathKind::Inductive,
+            }
+            // Relating types is always unproductive. If we were to map proof trees to
+            // corecursive functions as explained in #136824, relating types never
+            // introduces a constructor which could cause the recursion to be guarded.
+            GoalSource::TypeRelating => PathKind::Inductive,
+            // Instantiating a higher ranked goal can never cause the recursion to be
+            // guarded and is therefore unproductive.
+            GoalSource::InstantiateHigherRanked => PathKind::Inductive,
+            // These goal sources are likely unproductive and can be changed to
+            // `PathKind::Inductive`. Keeping them as unknown until we're confident
+            // about this and have an example where it is necessary.
+            GoalSource::AliasBoundConstCondition | GoalSource::AliasWellFormed => PathKind::Unknown,
         }
     }
 
@@ -606,7 +633,7 @@ where
 
             let (NestedNormalizationGoals(nested_goals), _, certainty) = self.evaluate_goal_raw(
                 GoalEvaluationKind::Nested,
-                GoalSource::Misc,
+                GoalSource::TypeRelating,
                 unconstrained_goal,
             )?;
             // Add the nested goals from normalization to our own nested goals.
@@ -683,7 +710,7 @@ where
     pub(super) fn add_normalizes_to_goal(&mut self, mut goal: Goal<I, ty::NormalizesTo<I>>) {
         goal.predicate = goal.predicate.fold_with(&mut ReplaceAliasWithInfer::new(
             self,
-            GoalSource::Misc,
+            GoalSource::TypeRelating,
             goal.param_env,
         ));
         self.inspect.add_normalizes_to_goal(self.delegate, self.max_input_universe, goal);
@@ -939,7 +966,15 @@ where
         rhs: T,
     ) -> Result<(), NoSolution> {
         let goals = self.delegate.relate(param_env, lhs, variance, rhs, self.origin_span)?;
-        self.add_goals(GoalSource::Misc, goals);
+        if cfg!(debug_assertions) {
+            for g in goals.iter() {
+                match g.predicate.kind().skip_binder() {
+                    ty::PredicateKind::Subtype { .. } | ty::PredicateKind::AliasRelate(..) => {}
+                    p => unreachable!("unexpected nested goal in `relate`: {p:?}"),
+                }
+            }
+        }
+        self.add_goals(GoalSource::TypeRelating, goals);
         Ok(())
     }
 

compiler/rustc_next_trait_solver/src/solve/inspect/build.rs

@@ -421,7 +421,7 @@ impl<D: SolverDelegate<Interner = I>, I: Interner> ProofTreeBuilder<D> {
         self.add_goal(
             delegate,
             max_input_universe,
-            GoalSource::Misc,
+            GoalSource::TypeRelating,
             goal.with(delegate.cx(), goal.predicate),
         );
     }

compiler/rustc_next_trait_solver/src/solve/mod.rs

@@ -313,7 +313,9 @@ where
                     ty::AliasRelationDirection::Equate,
                 ),
             );
-            self.add_goal(GoalSource::Misc, alias_relate_goal);
+            // We normalize the self type to be able to relate it with
+            // types from candidates.
+            self.add_goal(GoalSource::TypeRelating, alias_relate_goal);
             self.try_evaluate_added_goals()?;
             Ok(self.resolve_vars_if_possible(normalized_term))
         } else {

compiler/rustc_next_trait_solver/src/solve/project_goals.rs

@@ -24,7 +24,8 @@ where
                 ty::AliasRelationDirection::Equate,
             ),
         );
-        self.add_goal(GoalSource::Misc, goal);
+        // A projection goal holds if the alias is equal to the expected term.
+        self.add_goal(GoalSource::TypeRelating, goal);
         self.evaluate_added_goals_and_make_canonical_response(Certainty::Yes)
     }
 }

compiler/rustc_next_trait_solver/src/solve/search_graph.rs

@@ -1,9 +1,9 @@
 use std::convert::Infallible;
 use std::marker::PhantomData;
 
-use rustc_type_ir::Interner;
 use rustc_type_ir::search_graph::{self, PathKind};
-use rustc_type_ir::solve::{CanonicalInput, Certainty, QueryResult};
+use rustc_type_ir::solve::{CanonicalInput, Certainty, NoSolution, QueryResult};
+use rustc_type_ir::{Interner, TypingMode};
 
 use super::inspect::ProofTreeBuilder;
 use super::{FIXPOINT_STEP_LIMIT, has_no_inference_or_external_constraints};
@@ -47,7 +47,24 @@ where
     ) -> QueryResult<I> {
         match kind {
             PathKind::Coinductive => response_no_constraints(cx, input, Certainty::Yes),
-            PathKind::Inductive => response_no_constraints(cx, input, Certainty::overflow(false)),
+            PathKind::Unknown => response_no_constraints(cx, input, Certainty::overflow(false)),
+            // Even though we know these cycles to be unproductive, we still return
+            // overflow during coherence. This is both as we are not 100% confident in
+            // the implementation yet and any incorrect errors would be unsound there.
+            // The affected cases are also fairly artificial and not necessarily desirable
+            // so keeping this as ambiguity is fine for now.
+            //
+            // See `tests/ui/traits/next-solver/cycles/unproductive-in-coherence.rs` for an
+            // example where this would matter. We likely should change these cycles to `NoSolution`
+            // even in coherence once this is a bit more settled.
+            PathKind::Inductive => match input.typing_mode {
+                TypingMode::Coherence => {
+                    response_no_constraints(cx, input, Certainty::overflow(false))
+                }
+                TypingMode::Analysis { .. }
+                | TypingMode::PostBorrowckAnalysis { .. }
+                | TypingMode::PostAnalysis => Err(NoSolution),
+            },
         }
     }
 
@@ -57,12 +74,7 @@ where
         input: CanonicalInput<I>,
         result: QueryResult<I>,
     ) -> bool {
-        match kind {
+        Self::initial_provisional_result(cx, kind, input) == result
-            PathKind::Coinductive => response_no_constraints(cx, input, Certainty::Yes) == result,
-            PathKind::Inductive => {
-                response_no_constraints(cx, input, Certainty::overflow(false)) == result
-            }
-        }
     }
 
     fn on_stack_overflow(

compiler/rustc_parse/src/lib.rs

@@ -13,7 +13,6 @@
 #![feature(iter_intersperse)]
 #![feature(let_chains)]
 #![feature(string_from_utf8_lossy_owned)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 use std::path::{Path, PathBuf};

compiler/rustc_parse_format/src/lib.rs

@@ -13,7 +13,6 @@
     html_playground_url = "https://play.rust-lang.org/",
     test(attr(deny(warnings)))
 )]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 pub use Alignment::*;

compiler/rustc_passes/src/lib.rs

@@ -13,7 +13,6 @@
 #![feature(map_try_insert)]
 #![feature(rustdoc_internals)]
 #![feature(try_blocks)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 use rustc_middle::query::Providers;

compiler/rustc_pattern_analysis/src/lib.rs

@@ -6,7 +6,6 @@
 #![allow(rustc::diagnostic_outside_of_impl)]
 #![allow(rustc::untranslatable_diagnostic)]
 #![cfg_attr(feature = "rustc", feature(let_chains))]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 pub mod constructor;

compiler/rustc_pattern_analysis/tests/common/mod.rs

@@ -5,7 +5,7 @@ use rustc_pattern_analysis::usefulness::{PlaceValidity, UsefulnessReport};
 use rustc_pattern_analysis::{MatchArm, PatCx, PrivateUninhabitedField};
 
 /// Sets up `tracing` for easier debugging. Tries to look like the `rustc` setup.
-pub fn init_tracing() {
+fn init_tracing() {
     use tracing_subscriber::Layer;
     use tracing_subscriber::layer::SubscriberExt;
     use tracing_subscriber::util::SubscriberInitExt;
@@ -24,7 +24,7 @@ pub fn init_tracing() {
 /// A simple set of types.
 #[allow(dead_code)]
 #[derive(Debug, Copy, Clone, PartialEq, Eq)]
-pub enum Ty {
+pub(super) enum Ty {
     /// Booleans
     Bool,
     /// 8-bit unsigned integers
@@ -41,7 +41,7 @@ pub enum Ty {
 
 /// The important logic.
 impl Ty {
-    pub fn sub_tys(&self, ctor: &Constructor<Cx>) -> Vec<Self> {
+    pub(super) fn sub_tys(&self, ctor: &Constructor<Cx>) -> Vec<Self> {
         use Constructor::*;
         match (ctor, *self) {
             (Struct, Ty::Tuple(tys)) => tys.iter().copied().collect(),
@@ -63,7 +63,7 @@ impl Ty {
         }
     }
 
-    pub fn ctor_set(&self) -> ConstructorSet<Cx> {
+    fn ctor_set(&self) -> ConstructorSet<Cx> {
         match *self {
             Ty::Bool => ConstructorSet::Bool,
             Ty::U8 => ConstructorSet::Integers {
@@ -104,7 +104,7 @@ impl Ty {
         }
     }
 
-    pub fn write_variant_name(
+    fn write_variant_name(
         &self,
         f: &mut std::fmt::Formatter<'_>,
         ctor: &Constructor<Cx>,
@@ -120,7 +120,7 @@ impl Ty {
 }
 
 /// Compute usefulness in our simple context (and set up tracing for easier debugging).
-pub fn compute_match_usefulness<'p>(
+pub(super) fn compute_match_usefulness<'p>(
     arms: &[MatchArm<'p, Cx>],
     ty: Ty,
     scrut_validity: PlaceValidity,
@@ -137,7 +137,7 @@ pub fn compute_match_usefulness<'p>(
 }
 
 #[derive(Debug)]
-pub struct Cx;
+pub(super) struct Cx;
 
 /// The context for pattern analysis. Forwards anything interesting to `Ty` methods.
 impl PatCx for Cx {

compiler/rustc_privacy/src/lib.rs

@@ -7,7 +7,6 @@
 #![feature(let_chains)]
 #![feature(rustdoc_internals)]
 #![feature(try_blocks)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 mod errors;

compiler/rustc_query_impl/src/lib.rs

@@ -9,7 +9,6 @@
 #![feature(min_specialization)]
 #![feature(rustc_attrs)]
 #![feature(rustdoc_internals)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 use rustc_data_structures::stable_hasher::HashStable;

compiler/rustc_query_system/src/dep_graph/graph.rs

@@ -1,5 +1,4 @@
 use std::assert_matches::assert_matches;
-use std::collections::hash_map::Entry;
 use std::fmt::Debug;
 use std::hash::Hash;
 use std::marker::PhantomData;
@@ -9,7 +8,7 @@ use std::sync::atomic::{AtomicU32, Ordering};
 use rustc_data_structures::fingerprint::Fingerprint;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_data_structures::profiling::{QueryInvocationId, SelfProfilerRef};
-use rustc_data_structures::sharded::{self, Sharded};
+use rustc_data_structures::sharded::{self, ShardedHashMap};
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_data_structures::sync::{AtomicU64, Lock};
 use rustc_data_structures::unord::UnordMap;
@@ -619,7 +618,7 @@ impl<D: Deps> DepGraphData<D> {
         if let Some(prev_index) = self.previous.node_to_index_opt(dep_node) {
             self.current.prev_index_to_index.lock()[prev_index]
         } else {
-            self.current.new_node_to_index.lock_shard_by_value(dep_node).get(dep_node).copied()
+            self.current.new_node_to_index.get(dep_node)
         }
     }
 
@@ -1048,7 +1047,7 @@ rustc_index::newtype_index! {
 /// first, and `data` second.
 pub(super) struct CurrentDepGraph<D: Deps> {
     encoder: GraphEncoder<D>,
-    new_node_to_index: Sharded<FxHashMap<DepNode, DepNodeIndex>>,
+    new_node_to_index: ShardedHashMap<DepNode, DepNodeIndex>,
     prev_index_to_index: Lock<IndexVec<SerializedDepNodeIndex, Option<DepNodeIndex>>>,
 
     /// This is used to verify that fingerprints do not change between the creation of a node
@@ -1117,12 +1116,9 @@ impl<D: Deps> CurrentDepGraph<D> {
                 profiler,
                 previous,
             ),
-            new_node_to_index: Sharded::new(|| {
+            new_node_to_index: ShardedHashMap::with_capacity(
-                FxHashMap::with_capacity_and_hasher(
                 new_node_count_estimate / sharded::shards(),
-                    Default::default(),
+            ),
-                )
-            }),
             prev_index_to_index: Lock::new(IndexVec::from_elem_n(None, prev_graph_node_count)),
             anon_id_seed,
             #[cfg(debug_assertions)]
@@ -1152,14 +1148,9 @@ impl<D: Deps> CurrentDepGraph<D> {
         edges: EdgesVec,
         current_fingerprint: Fingerprint,
     ) -> DepNodeIndex {
-        let dep_node_index = match self.new_node_to_index.lock_shard_by_value(&key).entry(key) {
+        let dep_node_index = self
-            Entry::Occupied(entry) => *entry.get(),
+            .new_node_to_index
-            Entry::Vacant(entry) => {
+            .get_or_insert_with(key, || self.encoder.send(key, current_fingerprint, edges));
-                let dep_node_index = self.encoder.send(key, current_fingerprint, edges);
-                entry.insert(dep_node_index);
-                dep_node_index
-            }
-        };
 
         #[cfg(debug_assertions)]
         self.record_edge(dep_node_index, key, current_fingerprint);
@@ -1257,7 +1248,7 @@ impl<D: Deps> CurrentDepGraph<D> {
     ) {
         let node = &prev_graph.index_to_node(prev_index);
         debug_assert!(
-            !self.new_node_to_index.lock_shard_by_value(node).contains_key(node),
+            !self.new_node_to_index.get(node).is_some(),
             "node from previous graph present in new node collection"
         );
     }
@@ -1382,7 +1373,7 @@ fn panic_on_forbidden_read<D: Deps>(data: &DepGraphData<D>, dep_node_index: DepN
     if dep_node.is_none() {
         // Try to find it among the new nodes
         for shard in data.current.new_node_to_index.lock_shards() {
-            if let Some((node, _)) = shard.iter().find(|(_, index)| **index == dep_node_index) {
+            if let Some((node, _)) = shard.iter().find(|(_, index)| *index == dep_node_index) {
                 dep_node = Some(*node);
                 break;
             }

compiler/rustc_query_system/src/lib.rs

@@ -3,10 +3,8 @@
 #![feature(assert_matches)]
 #![feature(core_intrinsics)]
 #![feature(dropck_eyepatch)]
-#![feature(hash_raw_entry)]
 #![feature(let_chains)]
 #![feature(min_specialization)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 pub mod cache;

compiler/rustc_query_system/src/query/caches.rs

@@ -2,8 +2,7 @@ use std::fmt::Debug;
 use std::hash::Hash;
 use std::sync::OnceLock;
 
-use rustc_data_structures::fx::FxHashMap;
+use rustc_data_structures::sharded::ShardedHashMap;
-use rustc_data_structures::sharded::{self, Sharded};
 pub use rustc_data_structures::vec_cache::VecCache;
 use rustc_hir::def_id::LOCAL_CRATE;
 use rustc_index::Idx;
@@ -36,7 +35,7 @@ pub trait QueryCache: Sized {
 /// In-memory cache for queries whose keys aren't suitable for any of the
 /// more specialized kinds of cache. Backed by a sharded hashmap.
 pub struct DefaultCache<K, V> {
-    cache: Sharded<FxHashMap<K, (V, DepNodeIndex)>>,
+    cache: ShardedHashMap<K, (V, DepNodeIndex)>,
 }
 
 impl<K, V> Default for DefaultCache<K, V> {
@@ -55,19 +54,14 @@ where
 
     #[inline(always)]
     fn lookup(&self, key: &K) -> Option<(V, DepNodeIndex)> {
-        let key_hash = sharded::make_hash(key);
+        self.cache.get(key)
-        let lock = self.cache.lock_shard_by_hash(key_hash);
-        let result = lock.raw_entry().from_key_hashed_nocheck(key_hash, key);
-
-        if let Some((_, value)) = result { Some(*value) } else { None }
     }
 
     #[inline]
     fn complete(&self, key: K, value: V, index: DepNodeIndex) {
-        let mut lock = self.cache.lock_shard_by_value(&key);
         // We may be overwriting another value. This is all right, since the dep-graph
         // will check that the fingerprint matches.
-        lock.insert(key, (value, index));
+        self.cache.insert(key, (value, index));
     }
 
     fn iter(&self, f: &mut dyn FnMut(&Self::Key, &Self::Value, DepNodeIndex)) {

compiler/rustc_resolve/src/lib.rs

@@ -20,7 +20,6 @@
 #![feature(let_chains)]
 #![feature(rustc_attrs)]
 #![feature(rustdoc_internals)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 use std::cell::{Cell, RefCell};

compiler/rustc_sanitizers/src/lib.rs

@@ -6,7 +6,6 @@
 // tidy-alphabetical-start
 #![cfg_attr(doc, recursion_limit = "256")] // FIXME(nnethercote): will be removed by #124141
 #![feature(let_chains)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 pub mod cfi;

compiler/rustc_serialize/src/lib.rs

@@ -14,7 +14,6 @@
 #![feature(min_specialization)]
 #![feature(never_type)]
 #![feature(rustdoc_internals)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 pub use self::serialize::{Decodable, Decoder, Encodable, Encoder};

compiler/rustc_session/src/lib.rs

@@ -7,7 +7,6 @@
 // To generate CodegenOptionsTargetModifiers and UnstableOptionsTargetModifiers enums
 // with macro_rules, it is necessary to use recursive mechanic ("Incremental TT Munchers").
 #![recursion_limit = "256"]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 pub mod errors;

compiler/rustc_smir/src/lib.rs

@@ -16,7 +16,6 @@
 )]
 #![doc(rust_logo)]
 #![feature(rustdoc_internals)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 pub mod rustc_internal;

compiler/rustc_span/src/lib.rs

@@ -32,7 +32,6 @@
 #![feature(rustc_attrs)]
 #![feature(rustdoc_internals)]
 #![feature(slice_as_chunks)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 // The code produced by the `Encodable`/`Decodable` derive macros refer to

compiler/rustc_symbol_mangling/src/lib.rs

@@ -94,7 +94,6 @@
 #![doc(rust_logo)]
 #![feature(let_chains)]
 #![feature(rustdoc_internals)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 use rustc_hir::def::DefKind;

compiler/rustc_target/src/lib.rs

@@ -16,7 +16,6 @@
 #![feature(let_chains)]
 #![feature(rustc_attrs)]
 #![feature(rustdoc_internals)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 use std::path::{Path, PathBuf};

compiler/rustc_trait_selection/src/lib.rs

@@ -31,7 +31,6 @@
 #![feature(unwrap_infallible)]
 #![feature(yeet_expr)]
 #![recursion_limit = "512"] // For rustdoc
-#![warn(unreachable_pub)] // For rustdoc
 // tidy-alphabetical-end
 
 pub mod error_reporting;

compiler/rustc_trait_selection/src/solve/fulfill/derive_errors.rs

@@ -440,7 +440,7 @@ impl<'tcx> ProofTreeVisitor<'tcx> for BestObligation<'tcx> {
             match (child_mode, nested_goal.source()) {
                 (
                     ChildMode::Trait(_) | ChildMode::Host(_),
-                    GoalSource::Misc | GoalSource::NormalizeGoal(_),
+                    GoalSource::Misc | GoalSource::TypeRelating | GoalSource::NormalizeGoal(_),
                 ) => {
                     continue;
                 }

compiler/rustc_traits/src/lib.rs

@@ -2,7 +2,6 @@
 
 // tidy-alphabetical-start
 #![recursion_limit = "256"]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 mod codegen;

compiler/rustc_transmute/src/lib.rs

@@ -1,7 +1,6 @@
 // tidy-alphabetical-start
 #![cfg_attr(doc, recursion_limit = "256")] // FIXME(nnethercote): will be removed by #124141
 #![feature(never_type)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 pub(crate) use rustc_data_structures::fx::{FxIndexMap as Map, FxIndexSet as Set};

compiler/rustc_ty_utils/src/lib.rs

@@ -17,7 +17,6 @@
 #![feature(let_chains)]
 #![feature(never_type)]
 #![feature(rustdoc_internals)]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 use rustc_middle::query::Providers;

compiler/rustc_type_ir/src/lib.rs

@@ -6,7 +6,6 @@
     feature(associated_type_defaults, never_type, rustc_attrs, negative_impls)
 )]
 #![cfg_attr(feature = "nightly", allow(internal_features))]
-#![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
 extern crate self as rustc_type_ir;

compiler/rustc_type_ir/src/search_graph/mod.rs

@@ -13,6 +13,7 @@
 /// behavior as long as the resulting behavior is still correct.
 use std::cmp::Ordering;
 use std::collections::BTreeMap;
+use std::collections::hash_map::Entry;
 use std::fmt::Debug;
 use std::hash::Hash;
 use std::marker::PhantomData;
@@ -20,7 +21,7 @@ use std::marker::PhantomData;
 use derive_where::derive_where;
 use rustc_index::{Idx, IndexVec};
 #[cfg(feature = "nightly")]
-use rustc_macros::HashStable_NoContext;
+use rustc_macros::{HashStable_NoContext, TyDecodable, TyEncodable};
 use tracing::debug;
 
 use crate::data_structures::HashMap;
@@ -111,21 +112,35 @@ pub trait Delegate {
 /// In the initial iteration of a cycle, we do not yet have a provisional
 /// result. In the case we return an initial provisional result depending
 /// on the kind of cycle.
-#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
-#[cfg_attr(feature = "nightly", derive(HashStable_NoContext))]
+#[cfg_attr(feature = "nightly", derive(TyDecodable, TyEncodable, HashStable_NoContext))]
 pub enum PathKind {
-    Coinductive,
+    /// A path consisting of only inductive/unproductive steps. Their initial
+    /// provisional result is `Err(NoSolution)`. We currently treat them as
+    /// `PathKind::Unknown` during coherence until we're fully confident in
+    /// our approach.
     Inductive,
+    /// A path which is not be coinductive right now but we may want
+    /// to change of them to be so in the future. We return an ambiguous
+    /// result in this case to prevent people from relying on this.
+    Unknown,
+    /// A path with at least one coinductive step. Such cycles hold.
+    Coinductive,
 }
+
 impl PathKind {
     /// Returns the path kind when merging `self` with `rest`.
     ///
     /// Given an inductive path `self` and a coinductive path `rest`,
     /// the path `self -> rest` would be coinductive.
+    ///
+    /// This operation represents an ordering and would be equivalent
+    /// to `max(self, rest)`.
     fn extend(self, rest: PathKind) -> PathKind {
-        match self {
+        match (self, rest) {
-            PathKind::Coinductive => PathKind::Coinductive,
+            (PathKind::Coinductive, _) | (_, PathKind::Coinductive) => PathKind::Coinductive,
-            PathKind::Inductive => rest,
+            (PathKind::Unknown, _) | (_, PathKind::Unknown) => PathKind::Unknown,
+            (PathKind::Inductive, PathKind::Inductive) => PathKind::Inductive,
         }
     }
 }
@@ -159,9 +174,6 @@ impl UsageKind {
             }
         }
     }
-    fn and_merge(&mut self, other: impl Into<Self>) {
-        *self = self.merge(other);
-    }
 }
 
 /// For each goal we track whether the paths from this goal
@@ -297,7 +309,7 @@ impl CycleHeads {
 
             let path_from_entry = match step_kind {
                 PathKind::Coinductive => AllPathsToHeadCoinductive::Yes,
-                PathKind::Inductive => path_from_entry,
+                PathKind::Unknown | PathKind::Inductive => path_from_entry,
             };
 
             self.insert(head, path_from_entry);
@@ -305,6 +317,63 @@ impl CycleHeads {
     }
 }
 
+bitflags::bitflags! {
+    /// Tracks how nested goals have been accessed. This is necessary to disable
+    /// global cache entries if computing them would otherwise result in a cycle or
+    /// access a provisional cache entry.
+    #[derive(Debug, Clone, Copy)]
+    pub struct PathsToNested: u8 {
+        /// The initial value when adding a goal to its own nested goals.
+        const EMPTY                      = 1 << 0;
+        const INDUCTIVE                  = 1 << 1;
+        const UNKNOWN                    = 1 << 2;
+        const COINDUCTIVE                = 1 << 3;
+    }
+}
+impl From<PathKind> for PathsToNested {
+    fn from(path: PathKind) -> PathsToNested {
+        match path {
+            PathKind::Inductive => PathsToNested::INDUCTIVE,
+            PathKind::Unknown => PathsToNested::UNKNOWN,
+            PathKind::Coinductive => PathsToNested::COINDUCTIVE,
+        }
+    }
+}
+impl PathsToNested {
+    /// The implementation of this function is kind of ugly. We check whether
+    /// there currently exist 'weaker' paths in the set, if so we upgrade these
+    /// paths to at least `path`.
+    #[must_use]
+    fn extend_with(mut self, path: PathKind) -> Self {
+        match path {
+            PathKind::Inductive => {
+                if self.intersects(PathsToNested::EMPTY) {
+                    self.remove(PathsToNested::EMPTY);
+                    self.insert(PathsToNested::INDUCTIVE);
+                }
+            }
+            PathKind::Unknown => {
+                if self.intersects(PathsToNested::EMPTY | PathsToNested::INDUCTIVE) {
+                    self.remove(PathsToNested::EMPTY | PathsToNested::INDUCTIVE);
+                    self.insert(PathsToNested::UNKNOWN);
+                }
+            }
+            PathKind::Coinductive => {
+                if self.intersects(
+                    PathsToNested::EMPTY | PathsToNested::INDUCTIVE | PathsToNested::UNKNOWN,
+                ) {
+                    self.remove(
+                        PathsToNested::EMPTY | PathsToNested::INDUCTIVE | PathsToNested::UNKNOWN,
+                    );
+                    self.insert(PathsToNested::COINDUCTIVE);
+                }
+            }
+        }
+
+        self
+    }
+}
+
 /// The nested goals of each stack entry and the path from the
 /// stack entry to that nested goal.
 ///
@@ -322,15 +391,18 @@ impl CycleHeads {
 /// results from a the cycle BAB depending on the cycle root.
 #[derive_where(Debug, Default, Clone; X: Cx)]
 struct NestedGoals<X: Cx> {
-    nested_goals: HashMap<X::Input, UsageKind>,
+    nested_goals: HashMap<X::Input, PathsToNested>,
 }
 impl<X: Cx> NestedGoals<X> {
     fn is_empty(&self) -> bool {
         self.nested_goals.is_empty()
     }
 
-    fn insert(&mut self, input: X::Input, path_from_entry: UsageKind) {
+    fn insert(&mut self, input: X::Input, paths_to_nested: PathsToNested) {
-        self.nested_goals.entry(input).or_insert(path_from_entry).and_merge(path_from_entry);
+        match self.nested_goals.entry(input) {
+            Entry::Occupied(mut entry) => *entry.get_mut() |= paths_to_nested,
+            Entry::Vacant(entry) => drop(entry.insert(paths_to_nested)),
+        }
     }
 
     /// Adds the nested goals of a nested goal, given that the path `step_kind` from this goal
@@ -341,18 +413,15 @@ impl<X: Cx> NestedGoals<X> {
     /// the same as for the child.
     fn extend_from_child(&mut self, step_kind: PathKind, nested_goals: &NestedGoals<X>) {
         #[allow(rustc::potential_query_instability)]
-        for (input, path_from_entry) in nested_goals.iter() {
+        for (input, paths_to_nested) in nested_goals.iter() {
-            let path_from_entry = match step_kind {
+            let paths_to_nested = paths_to_nested.extend_with(step_kind);
-                PathKind::Coinductive => UsageKind::Single(PathKind::Coinductive),
+            self.insert(input, paths_to_nested);
-                PathKind::Inductive => path_from_entry,
-            };
-            self.insert(input, path_from_entry);
         }
     }
 
     #[cfg_attr(feature = "nightly", rustc_lint_query_instability)]
     #[allow(rustc::potential_query_instability)]
-    fn iter(&self) -> impl Iterator<Item = (X::Input, UsageKind)> {
+    fn iter(&self) -> impl Iterator<Item = (X::Input, PathsToNested)> + '_ {
         self.nested_goals.iter().map(|(i, p)| (*i, *p))
     }
 
@@ -490,7 +559,7 @@ impl<D: Delegate<Cx = X>, X: Cx> SearchGraph<D> {
             // goals as this change may cause them to now depend on additional
             // goals, resulting in new cycles. See the dev-guide for examples.
             if parent_depends_on_cycle {
-                parent.nested_goals.insert(parent.input, UsageKind::Single(PathKind::Inductive))
+                parent.nested_goals.insert(parent.input, PathsToNested::EMPTY);
             }
         }
     }
@@ -666,7 +735,7 @@ impl<D: Delegate<Cx = X>, X: Cx> SearchGraph<D> {
             //
             // We must therefore not use the global cache entry for `B` in that case.
             // See tests/ui/traits/next-solver/cycles/hidden-by-overflow.rs
-            last.nested_goals.insert(last.input, UsageKind::Single(PathKind::Inductive));
+            last.nested_goals.insert(last.input, PathsToNested::EMPTY);
         }
 
         debug!("encountered stack overflow");
@@ -749,16 +818,11 @@ impl<D: Delegate<Cx = X>, X: Cx> SearchGraph<D> {
 
                 // We now care about the path from the next highest cycle head to the
                 // provisional cache entry.
-                match path_from_head {
+                *path_from_head = path_from_head.extend(Self::cycle_path_kind(
-                    PathKind::Coinductive => {}
-                    PathKind::Inductive => {
-                        *path_from_head = Self::cycle_path_kind(
                     &self.stack,
                     stack_entry.step_kind_from_parent,
                     head,
-                        )
+                ));
-                    }
-                }
                 // Mutate the result of the provisional cache entry in case we did
                 // not reach a fixpoint.
                 *result = mutate_result(input, *result);
@@ -858,7 +922,7 @@ impl<D: Delegate<Cx = X>, X: Cx> SearchGraph<D> {
             for &ProvisionalCacheEntry {
                 encountered_overflow,
                 ref heads,
-                path_from_head,
+                path_from_head: head_to_provisional,
                 result: _,
             } in entries.iter()
             {
@@ -870,25 +934,20 @@ impl<D: Delegate<Cx = X>, X: Cx> SearchGraph<D> {
 
                 // A provisional cache entry only applies if the path from its highest head
                 // matches the path when encountering the goal.
+                //
+                // We check if any of the paths taken while computing the global goal
+                // would end up with an applicable provisional cache entry.
                 let head = heads.highest_cycle_head();
-                let full_path = match Self::cycle_path_kind(stack, step_kind_from_parent, head) {
+                let head_to_curr = Self::cycle_path_kind(stack, step_kind_from_parent, head);
-                    PathKind::Coinductive => UsageKind::Single(PathKind::Coinductive),
+                let full_paths = path_from_global_entry.extend_with(head_to_curr);
-                    PathKind::Inductive => path_from_global_entry,
+                if full_paths.contains(head_to_provisional.into()) {
-                };
-
-                match (full_path, path_from_head) {
-                    (UsageKind::Mixed, _)
-                    | (UsageKind::Single(PathKind::Coinductive), PathKind::Coinductive)
-                    | (UsageKind::Single(PathKind::Inductive), PathKind::Inductive) => {
                     debug!(
-                            ?full_path,
+                        ?full_paths,
-                            ?path_from_head,
+                        ?head_to_provisional,
                         "cache entry not applicable due to matching paths"
                     );
                     return false;
                 }
-                    _ => debug!(?full_path, ?path_from_head, "paths don't match"),
-                }
             }
         }
 
@@ -986,8 +1045,8 @@ impl<D: Delegate<Cx = X>, X: Cx> SearchGraph<D> {
         let last = &mut self.stack[last_index];
         last.reached_depth = last.reached_depth.max(next_index);
 
-        last.nested_goals.insert(input, UsageKind::Single(step_kind_from_parent));
+        last.nested_goals.insert(input, step_kind_from_parent.into());
-        last.nested_goals.insert(last.input, UsageKind::Single(PathKind::Inductive));
+        last.nested_goals.insert(last.input, PathsToNested::EMPTY);
         if last_index != head {
             last.heads.insert(head, step_kind_from_parent);
         }

compiler/rustc_type_ir/src/solve/mod.rs

@@ -58,20 +58,24 @@ impl<I: Interner, P> Goal<I, P> {
 /// Why a specific goal has to be proven.
 ///
 /// This is necessary as we treat nested goals different depending on
-/// their source. This is currently mostly used by proof tree visitors
+/// their source. This is used to decide whether a cycle is coinductive.
-/// but will be used by cycle handling in the future.
+/// See the documentation of `EvalCtxt::step_kind_for_source` for more details
+/// about this.
+///
+/// It is also used by proof tree visitors, e.g. for diagnostics purposes.
 #[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
 #[cfg_attr(feature = "nightly", derive(HashStable_NoContext))]
 pub enum GoalSource {
     Misc,
-    /// We're proving a where-bound of an impl.
+    /// A nested goal required to prove that types are equal/subtypes.
+    /// This is always an unproductive step.
     ///
-    /// FIXME(-Znext-solver=coinductive): Explain how and why this
+    /// This is also used for all `NormalizesTo` goals as we they are used
-    /// changes whether cycles are coinductive.
+    /// to relate types in `AliasRelate`.
+    TypeRelating,
+    /// We're proving a where-bound of an impl.
     ImplWhereBound,
     /// Const conditions that need to hold for `~const` alias bounds to hold.
-    ///
-    /// FIXME(-Znext-solver=coinductive): Are these even coinductive?
     AliasBoundConstCondition,
     /// Instantiating a higher-ranked goal and re-proving it.
     InstantiateHigherRanked,
@@ -79,7 +83,6 @@ pub enum GoalSource {
     /// This is used in two places: projecting to an opaque whose hidden type
     /// is already registered in the opaque type storage, and for rigid projections.
     AliasWellFormed,
-
     /// In case normalizing aliases in nested goals cycles, eagerly normalizing these
     /// aliases in the context of the parent may incorrectly change the cycle kind.
     /// Normalizing aliases in goals therefore tracks the original path kind for this

library/alloc/src/boxed.rs

@@ -239,7 +239,7 @@ pub struct Box<
 /// This is the surface syntax for `box <expr>` expressions.
 #[rustc_intrinsic]
 #[unstable(feature = "liballoc_internals", issue = "none")]
-pub fn box_new<T>(_x: T) -> Box<T>;
+pub fn box_new<T>(x: T) -> Box<T>;
 
 impl<T> Box<T> {
     /// Allocates memory on the heap and then places `x` into it.

library/core/src/ffi/va_list.rs

@@ -306,15 +306,15 @@ impl<'f> Drop for VaListImpl<'f> {
 /// `va_copy`.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-unsafe fn va_end(_ap: &mut VaListImpl<'_>);
+unsafe fn va_end(ap: &mut VaListImpl<'_>);
 
 /// Copies the current location of arglist `src` to the arglist `dst`.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-unsafe fn va_copy<'f>(_dest: *mut VaListImpl<'f>, _src: &VaListImpl<'f>);
+unsafe fn va_copy<'f>(dest: *mut VaListImpl<'f>, src: &VaListImpl<'f>);
 
 /// Loads an argument of type `T` from the `va_list` `ap` and increment the
 /// argument `ap` points to.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-unsafe fn va_arg<T: sealed_trait::VaArgSafe>(_ap: &mut VaListImpl<'_>) -> T;
+unsafe fn va_arg<T: sealed_trait::VaArgSafe>(ap: &mut VaListImpl<'_>) -> T;

library/core/src/intrinsics/simd.rs

@@ -11,7 +11,7 @@
 /// `idx` must be in-bounds of the vector.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub const unsafe fn simd_insert<T, U>(_x: T, _idx: u32, _val: U) -> T;
+pub const unsafe fn simd_insert<T, U>(x: T, idx: u32, val: U) -> T;
 
 /// Extracts an element from a vector.
 ///
@@ -22,28 +22,28 @@ pub const unsafe fn simd_insert<T, U>(_x: T, _idx: u32, _val: U) -> T;
 /// `idx` must be in-bounds of the vector.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub const unsafe fn simd_extract<T, U>(_x: T, _idx: u32) -> U;
+pub const unsafe fn simd_extract<T, U>(x: T, idx: u32) -> U;
 
 /// Adds two simd vectors elementwise.
 ///
 /// `T` must be a vector of integers or floats.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_add<T>(_x: T, _y: T) -> T;
+pub unsafe fn simd_add<T>(x: T, y: T) -> T;
 
 /// Subtracts `rhs` from `lhs` elementwise.
 ///
 /// `T` must be a vector of integers or floats.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_sub<T>(_lhs: T, _rhs: T) -> T;
+pub unsafe fn simd_sub<T>(lhs: T, rhs: T) -> T;
 
 /// Multiplies two simd vectors elementwise.
 ///
 /// `T` must be a vector of integers or floats.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_mul<T>(_x: T, _y: T) -> T;
+pub unsafe fn simd_mul<T>(x: T, y: T) -> T;
 
 /// Divides `lhs` by `rhs` elementwise.
 ///
@@ -54,7 +54,7 @@ pub unsafe fn simd_mul<T>(_x: T, _y: T) -> T;
 /// Additionally for signed integers, `<int>::MIN / -1` is undefined behavior.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_div<T>(_lhs: T, _rhs: T) -> T;
+pub unsafe fn simd_div<T>(lhs: T, rhs: T) -> T;
 
 /// Returns remainder of two vectors elementwise.
 ///
@@ -65,7 +65,7 @@ pub unsafe fn simd_div<T>(_lhs: T, _rhs: T) -> T;
 /// Additionally for signed integers, `<int>::MIN / -1` is undefined behavior.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_rem<T>(_lhs: T, _rhs: T) -> T;
+pub unsafe fn simd_rem<T>(lhs: T, rhs: T) -> T;
 
 /// Shifts vector left elementwise, with UB on overflow.
 ///
@@ -78,7 +78,7 @@ pub unsafe fn simd_rem<T>(_lhs: T, _rhs: T) -> T;
 /// Each element of `rhs` must be less than `<int>::BITS`.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_shl<T>(_lhs: T, _rhs: T) -> T;
+pub unsafe fn simd_shl<T>(lhs: T, rhs: T) -> T;
 
 /// Shifts vector right elementwise, with UB on overflow.
 ///
@@ -91,28 +91,28 @@ pub unsafe fn simd_shl<T>(_lhs: T, _rhs: T) -> T;
 /// Each element of `rhs` must be less than `<int>::BITS`.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_shr<T>(_lhs: T, _rhs: T) -> T;
+pub unsafe fn simd_shr<T>(lhs: T, rhs: T) -> T;
 
 /// "Ands" vectors elementwise.
 ///
 /// `T` must be a vector of integers.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_and<T>(_x: T, _y: T) -> T;
+pub unsafe fn simd_and<T>(x: T, y: T) -> T;
 
 /// "Ors" vectors elementwise.
 ///
 /// `T` must be a vector of integers.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_or<T>(_x: T, _y: T) -> T;
+pub unsafe fn simd_or<T>(x: T, y: T) -> T;
 
 /// "Exclusive ors" vectors elementwise.
 ///
 /// `T` must be a vector of integers.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_xor<T>(_x: T, _y: T) -> T;
+pub unsafe fn simd_xor<T>(x: T, y: T) -> T;
 
 /// Numerically casts a vector, elementwise.
 ///
@@ -133,7 +133,7 @@ pub unsafe fn simd_xor<T>(_x: T, _y: T) -> T;
 /// * Be representable in the return type, after truncating off its fractional part
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_cast<T, U>(_x: T) -> U;
+pub unsafe fn simd_cast<T, U>(x: T) -> U;
 
 /// Numerically casts a vector, elementwise.
 ///
@@ -147,7 +147,7 @@ pub unsafe fn simd_cast<T, U>(_x: T) -> U;
 /// Otherwise, truncates or extends the value, maintaining the sign for signed integers.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_as<T, U>(_x: T) -> U;
+pub unsafe fn simd_as<T, U>(x: T) -> U;
 
 /// Negates a vector elementwise.
 ///
@@ -156,14 +156,14 @@ pub unsafe fn simd_as<T, U>(_x: T) -> U;
 /// Rust panics for `-<int>::Min` due to overflow, but it is not UB with this intrinsic.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_neg<T>(_x: T) -> T;
+pub unsafe fn simd_neg<T>(x: T) -> T;
 
 /// Returns absolute value of a vector, elementwise.
 ///
 /// `T` must be a vector of floating-point primitive types.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_fabs<T>(_x: T) -> T;
+pub unsafe fn simd_fabs<T>(x: T) -> T;
 
 /// Returns the minimum of two vectors, elementwise.
 ///
@@ -172,7 +172,7 @@ pub unsafe fn simd_fabs<T>(_x: T) -> T;
 /// Follows IEEE-754 `minNum` semantics.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_fmin<T>(_x: T, _y: T) -> T;
+pub unsafe fn simd_fmin<T>(x: T, y: T) -> T;
 
 /// Returns the maximum of two vectors, elementwise.
 ///
@@ -181,7 +181,7 @@ pub unsafe fn simd_fmin<T>(_x: T, _y: T) -> T;
 /// Follows IEEE-754 `maxNum` semantics.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_fmax<T>(_x: T, _y: T) -> T;
+pub unsafe fn simd_fmax<T>(x: T, y: T) -> T;
 
 /// Tests elementwise equality of two vectors.
 ///
@@ -192,7 +192,7 @@ pub unsafe fn simd_fmax<T>(_x: T, _y: T) -> T;
 /// Returns `0` for false and `!0` for true.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_eq<T, U>(_x: T, _y: T) -> U;
+pub unsafe fn simd_eq<T, U>(x: T, y: T) -> U;
 
 /// Tests elementwise inequality equality of two vectors.
 ///
@@ -203,7 +203,7 @@ pub unsafe fn simd_eq<T, U>(_x: T, _y: T) -> U;
 /// Returns `0` for false and `!0` for true.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_ne<T, U>(_x: T, _y: T) -> U;
+pub unsafe fn simd_ne<T, U>(x: T, y: T) -> U;
 
 /// Tests if `x` is less than `y`, elementwise.
 ///
@@ -214,7 +214,7 @@ pub unsafe fn simd_ne<T, U>(_x: T, _y: T) -> U;
 /// Returns `0` for false and `!0` for true.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_lt<T, U>(_x: T, _y: T) -> U;
+pub unsafe fn simd_lt<T, U>(x: T, y: T) -> U;
 
 /// Tests if `x` is less than or equal to `y`, elementwise.
 ///
@@ -225,7 +225,7 @@ pub unsafe fn simd_lt<T, U>(_x: T, _y: T) -> U;
 /// Returns `0` for false and `!0` for true.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_le<T, U>(_x: T, _y: T) -> U;
+pub unsafe fn simd_le<T, U>(x: T, y: T) -> U;
 
 /// Tests if `x` is greater than `y`, elementwise.
 ///
@@ -236,7 +236,7 @@ pub unsafe fn simd_le<T, U>(_x: T, _y: T) -> U;
 /// Returns `0` for false and `!0` for true.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_gt<T, U>(_x: T, _y: T) -> U;
+pub unsafe fn simd_gt<T, U>(x: T, y: T) -> U;
 
 /// Tests if `x` is greater than or equal to `y`, elementwise.
 ///
@@ -247,7 +247,7 @@ pub unsafe fn simd_gt<T, U>(_x: T, _y: T) -> U;
 /// Returns `0` for false and `!0` for true.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_ge<T, U>(_x: T, _y: T) -> U;
+pub unsafe fn simd_ge<T, U>(x: T, y: T) -> U;
 
 /// Shuffles two vectors by const indices.
 ///
@@ -263,7 +263,7 @@ pub unsafe fn simd_ge<T, U>(_x: T, _y: T) -> U;
 /// of `xy`.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_shuffle<T, U, V>(_x: T, _y: T, _idx: U) -> V;
+pub unsafe fn simd_shuffle<T, U, V>(x: T, y: T, idx: U) -> V;
 
 /// Reads a vector of pointers.
 ///
@@ -284,7 +284,7 @@ pub unsafe fn simd_shuffle<T, U, V>(_x: T, _y: T, _idx: U) -> V;
 /// `mask` must only contain `0` or `!0` values.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_gather<T, U, V>(_val: T, _ptr: U, _mask: V) -> T;
+pub unsafe fn simd_gather<T, U, V>(val: T, ptr: U, mask: V) -> T;
 
 /// Writes to a vector of pointers.
 ///
@@ -308,7 +308,7 @@ pub unsafe fn simd_gather<T, U, V>(_val: T, _ptr: U, _mask: V) -> T;
 /// `mask` must only contain `0` or `!0` values.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_scatter<T, U, V>(_val: T, _ptr: U, _mask: V);
+pub unsafe fn simd_scatter<T, U, V>(val: T, ptr: U, mask: V);
 
 /// Reads a vector of pointers.
 ///
@@ -331,7 +331,7 @@ pub unsafe fn simd_scatter<T, U, V>(_val: T, _ptr: U, _mask: V);
 /// `mask` must only contain `0` or `!0` values.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_masked_load<V, U, T>(_mask: V, _ptr: U, _val: T) -> T;
+pub unsafe fn simd_masked_load<V, U, T>(mask: V, ptr: U, val: T) -> T;
 
 /// Writes to a vector of pointers.
 ///
@@ -353,14 +353,14 @@ pub unsafe fn simd_masked_load<V, U, T>(_mask: V, _ptr: U, _val: T) -> T;
 /// `mask` must only contain `0` or `!0` values.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_masked_store<V, U, T>(_mask: V, _ptr: U, _val: T);
+pub unsafe fn simd_masked_store<V, U, T>(mask: V, ptr: U, val: T);
 
 /// Adds two simd vectors elementwise, with saturation.
 ///
 /// `T` must be a vector of integer primitive types.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_saturating_add<T>(_x: T, _y: T) -> T;
+pub unsafe fn simd_saturating_add<T>(x: T, y: T) -> T;
 
 /// Subtracts two simd vectors elementwise, with saturation.
 ///
@@ -369,7 +369,7 @@ pub unsafe fn simd_saturating_add<T>(_x: T, _y: T) -> T;
 /// Subtract `rhs` from `lhs`.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_saturating_sub<T>(_lhs: T, _rhs: T) -> T;
+pub unsafe fn simd_saturating_sub<T>(lhs: T, rhs: T) -> T;
 
 /// Adds elements within a vector from left to right.
 ///
@@ -380,7 +380,7 @@ pub unsafe fn simd_saturating_sub<T>(_lhs: T, _rhs: T) -> T;
 /// Starting with the value `y`, add the elements of `x` and accumulate.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_reduce_add_ordered<T, U>(_x: T, _y: U) -> U;
+pub unsafe fn simd_reduce_add_ordered<T, U>(x: T, y: U) -> U;
 
 /// Adds elements within a vector in arbitrary order. May also be re-associated with
 /// unordered additions on the inputs/outputs.
@@ -390,7 +390,7 @@ pub unsafe fn simd_reduce_add_ordered<T, U>(_x: T, _y: U) -> U;
 /// `U` must be the element type of `T`.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_reduce_add_unordered<T, U>(_x: T) -> U;
+pub unsafe fn simd_reduce_add_unordered<T, U>(x: T) -> U;
 
 /// Multiplies elements within a vector from left to right.
 ///
@@ -401,7 +401,7 @@ pub unsafe fn simd_reduce_add_unordered<T, U>(_x: T) -> U;
 /// Starting with the value `y`, multiply the elements of `x` and accumulate.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_reduce_mul_ordered<T, U>(_x: T, _y: U) -> U;
+pub unsafe fn simd_reduce_mul_ordered<T, U>(x: T, y: U) -> U;
 
 /// Multiplies elements within a vector in arbitrary order. May also be re-associated with
 /// unordered additions on the inputs/outputs.
@@ -411,7 +411,7 @@ pub unsafe fn simd_reduce_mul_ordered<T, U>(_x: T, _y: U) -> U;
 /// `U` must be the element type of `T`.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_reduce_mul_unordered<T, U>(_x: T) -> U;
+pub unsafe fn simd_reduce_mul_unordered<T, U>(x: T) -> U;
 
 /// Checks if all mask values are true.
 ///
@@ -421,7 +421,7 @@ pub unsafe fn simd_reduce_mul_unordered<T, U>(_x: T) -> U;
 /// `x` must contain only `0` or `!0`.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_reduce_all<T>(_x: T) -> bool;
+pub unsafe fn simd_reduce_all<T>(x: T) -> bool;
 
 /// Checks if any mask value is true.
 ///
@@ -431,7 +431,7 @@ pub unsafe fn simd_reduce_all<T>(_x: T) -> bool;
 /// `x` must contain only `0` or `!0`.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_reduce_any<T>(_x: T) -> bool;
+pub unsafe fn simd_reduce_any<T>(x: T) -> bool;
 
 /// Returns the maximum element of a vector.
 ///
@@ -442,7 +442,7 @@ pub unsafe fn simd_reduce_any<T>(_x: T) -> bool;
 /// For floating-point values, uses IEEE-754 `maxNum`.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_reduce_max<T, U>(_x: T) -> U;
+pub unsafe fn simd_reduce_max<T, U>(x: T) -> U;
 
 /// Returns the minimum element of a vector.
 ///
@@ -453,7 +453,7 @@ pub unsafe fn simd_reduce_max<T, U>(_x: T) -> U;
 /// For floating-point values, uses IEEE-754 `minNum`.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_reduce_min<T, U>(_x: T) -> U;
+pub unsafe fn simd_reduce_min<T, U>(x: T) -> U;
 
 /// Logical "ands" all elements together.
 ///
@@ -462,7 +462,7 @@ pub unsafe fn simd_reduce_min<T, U>(_x: T) -> U;
 /// `U` must be the element type of `T`.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_reduce_and<T, U>(_x: T) -> U;
+pub unsafe fn simd_reduce_and<T, U>(x: T) -> U;
 
 /// Logical "ors" all elements together.
 ///
@@ -471,7 +471,7 @@ pub unsafe fn simd_reduce_and<T, U>(_x: T) -> U;
 /// `U` must be the element type of `T`.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_reduce_or<T, U>(_x: T) -> U;
+pub unsafe fn simd_reduce_or<T, U>(x: T) -> U;
 
 /// Logical "exclusive ors" all elements together.
 ///
@@ -480,7 +480,7 @@ pub unsafe fn simd_reduce_or<T, U>(_x: T) -> U;
 /// `U` must be the element type of `T`.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_reduce_xor<T, U>(_x: T) -> U;
+pub unsafe fn simd_reduce_xor<T, U>(x: T) -> U;
 
 /// Truncates an integer vector to a bitmask.
 ///
@@ -517,7 +517,7 @@ pub unsafe fn simd_reduce_xor<T, U>(_x: T) -> U;
 /// `x` must contain only `0` and `!0`.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_bitmask<T, U>(_x: T) -> U;
+pub unsafe fn simd_bitmask<T, U>(x: T) -> U;
 
 /// Selects elements from a mask.
 ///
@@ -533,7 +533,7 @@ pub unsafe fn simd_bitmask<T, U>(_x: T) -> U;
 /// `mask` must only contain `0` and `!0`.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_select<M, T>(_mask: M, _if_true: T, _if_false: T) -> T;
+pub unsafe fn simd_select<M, T>(mask: M, if_true: T, if_false: T) -> T;
 
 /// Selects elements from a bitmask.
 ///
@@ -551,7 +551,7 @@ pub unsafe fn simd_select<M, T>(_mask: M, _if_true: T, _if_false: T) -> T;
 /// Padding bits must be all zero.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_select_bitmask<M, T>(_m: M, _yes: T, _no: T) -> T;
+pub unsafe fn simd_select_bitmask<M, T>(m: M, yes: T, no: T) -> T;
 
 /// Calculates the offset from a pointer vector elementwise, potentially
 /// wrapping.
@@ -563,14 +563,14 @@ pub unsafe fn simd_select_bitmask<M, T>(_m: M, _yes: T, _no: T) -> T;
 /// Operates as if by `<ptr>::wrapping_offset`.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_arith_offset<T, U>(_ptr: T, _offset: U) -> T;
+pub unsafe fn simd_arith_offset<T, U>(ptr: T, offset: U) -> T;
 
 /// Casts a vector of pointers.
 ///
 /// `T` and `U` must be vectors of pointers with the same number of elements.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_cast_ptr<T, U>(_ptr: T) -> U;
+pub unsafe fn simd_cast_ptr<T, U>(ptr: T) -> U;
 
 /// Exposes a vector of pointers as a vector of addresses.
 ///
@@ -579,7 +579,7 @@ pub unsafe fn simd_cast_ptr<T, U>(_ptr: T) -> U;
 /// `U` must be a vector of `usize` with the same length as `T`.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_expose_provenance<T, U>(_ptr: T) -> U;
+pub unsafe fn simd_expose_provenance<T, U>(ptr: T) -> U;
 
 /// Creates a vector of pointers from a vector of addresses.
 ///
@@ -588,56 +588,56 @@ pub unsafe fn simd_expose_provenance<T, U>(_ptr: T) -> U;
 /// `U` must be a vector of pointers, with the same length as `T`.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_with_exposed_provenance<T, U>(_addr: T) -> U;
+pub unsafe fn simd_with_exposed_provenance<T, U>(addr: T) -> U;
 
 /// Swaps bytes of each element.
 ///
 /// `T` must be a vector of integers.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_bswap<T>(_x: T) -> T;
+pub unsafe fn simd_bswap<T>(x: T) -> T;
 
 /// Reverses bits of each element.
 ///
 /// `T` must be a vector of integers.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_bitreverse<T>(_x: T) -> T;
+pub unsafe fn simd_bitreverse<T>(x: T) -> T;
 
 /// Counts the leading zeros of each element.
 ///
 /// `T` must be a vector of integers.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_ctlz<T>(_x: T) -> T;
+pub unsafe fn simd_ctlz<T>(x: T) -> T;
 
 /// Counts the number of ones in each element.
 ///
 /// `T` must be a vector of integers.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_ctpop<T>(_x: T) -> T;
+pub unsafe fn simd_ctpop<T>(x: T) -> T;
 
 /// Counts the trailing zeros of each element.
 ///
 /// `T` must be a vector of integers.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_cttz<T>(_x: T) -> T;
+pub unsafe fn simd_cttz<T>(x: T) -> T;
 
 /// Rounds up each element to the next highest integer-valued float.
 ///
 /// `T` must be a vector of floats.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_ceil<T>(_x: T) -> T;
+pub unsafe fn simd_ceil<T>(x: T) -> T;
 
 /// Rounds down each element to the next lowest integer-valued float.
 ///
 /// `T` must be a vector of floats.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_floor<T>(_x: T) -> T;
+pub unsafe fn simd_floor<T>(x: T) -> T;
 
 /// Rounds each element to the closest integer-valued float.
 /// Ties are resolved by rounding away from 0.
@@ -645,7 +645,7 @@ pub unsafe fn simd_floor<T>(_x: T) -> T;
 /// `T` must be a vector of floats.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_round<T>(_x: T) -> T;
+pub unsafe fn simd_round<T>(x: T) -> T;
 
 /// Returns the integer part of each element as an integer-valued float.
 /// In other words, non-integer values are truncated towards zero.
@@ -653,21 +653,21 @@ pub unsafe fn simd_round<T>(_x: T) -> T;
 /// `T` must be a vector of floats.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_trunc<T>(_x: T) -> T;
+pub unsafe fn simd_trunc<T>(x: T) -> T;
 
 /// Takes the square root of each element.
 ///
 /// `T` must be a vector of floats.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_fsqrt<T>(_x: T) -> T;
+pub unsafe fn simd_fsqrt<T>(x: T) -> T;
 
 /// Computes `(x*y) + z` for each element, but without any intermediate rounding.
 ///
 /// `T` must be a vector of floats.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_fma<T>(_x: T, _y: T, _z: T) -> T;
+pub unsafe fn simd_fma<T>(x: T, y: T, z: T) -> T;
 
 /// Computes `(x*y) + z` for each element, non-deterministically executing either
 /// a fused multiply-add or two operations with rounding of the intermediate result.
@@ -682,53 +682,53 @@ pub unsafe fn simd_fma<T>(_x: T, _y: T, _z: T) -> T;
 /// `T` must be a vector of floats.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_relaxed_fma<T>(_x: T, _y: T, _z: T) -> T;
+pub unsafe fn simd_relaxed_fma<T>(x: T, y: T, z: T) -> T;
 
 // Computes the sine of each element.
 ///
 /// `T` must be a vector of floats.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_fsin<T>(_a: T) -> T;
+pub unsafe fn simd_fsin<T>(a: T) -> T;
 
 // Computes the cosine of each element.
 ///
 /// `T` must be a vector of floats.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_fcos<T>(_a: T) -> T;
+pub unsafe fn simd_fcos<T>(a: T) -> T;
 
 // Computes the exponential function of each element.
 ///
 /// `T` must be a vector of floats.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_fexp<T>(_a: T) -> T;
+pub unsafe fn simd_fexp<T>(a: T) -> T;
 
 // Computes 2 raised to the power of each element.
 ///
 /// `T` must be a vector of floats.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_fexp2<T>(_a: T) -> T;
+pub unsafe fn simd_fexp2<T>(a: T) -> T;
 
 // Computes the base 10 logarithm of each element.
 ///
 /// `T` must be a vector of floats.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_flog10<T>(_a: T) -> T;
+pub unsafe fn simd_flog10<T>(a: T) -> T;
 
 // Computes the base 2 logarithm of each element.
 ///
 /// `T` must be a vector of floats.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_flog2<T>(_a: T) -> T;
+pub unsafe fn simd_flog2<T>(a: T) -> T;
 
 // Computes the natural logarithm of each element.
 ///
 /// `T` must be a vector of floats.
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn simd_flog<T>(_a: T) -> T;
+pub unsafe fn simd_flog<T>(a: T) -> T;

library/std/src/sys/fs/uefi.rs

@@ -1,14 +1,21 @@
 use crate::ffi::OsString;
 use crate::fmt;
-use crate::hash::{Hash, Hasher};
+use crate::hash::Hash;
 use crate::io::{self, BorrowedCursor, IoSlice, IoSliceMut, SeekFrom};
 use crate::path::{Path, PathBuf};
 use crate::sys::time::SystemTime;
 use crate::sys::unsupported;
 
+#[expect(dead_code)]
+const FILE_PERMISSIONS_MASK: u64 = r_efi::protocols::file::READ_ONLY;
+
 pub struct File(!);
 
-pub struct FileAttr(!);
+#[derive(Clone)]
+pub struct FileAttr {
+    attr: u64,
+    size: u64,
+}
 
 pub struct ReadDir(!);
 
@@ -20,42 +27,40 @@ pub struct OpenOptions {}
 #[derive(Copy, Clone, Debug, Default)]
 pub struct FileTimes {}
 
-pub struct FilePermissions(!);
+#[derive(Clone, PartialEq, Eq, Debug)]
+// Bool indicates if file is readonly
+pub struct FilePermissions(bool);
 
-pub struct FileType(!);
+#[derive(Clone, Copy, PartialEq, Eq, Hash, Debug)]
+// Bool indicates if directory
+pub struct FileType(bool);
 
 #[derive(Debug)]
 pub struct DirBuilder {}
 
 impl FileAttr {
     pub fn size(&self) -> u64 {
-        self.0
+        self.size
     }
 
     pub fn perm(&self) -> FilePermissions {
-        self.0
+        FilePermissions::from_attr(self.attr)
     }
 
     pub fn file_type(&self) -> FileType {
-        self.0
+        FileType::from_attr(self.attr)
     }
 
     pub fn modified(&self) -> io::Result<SystemTime> {
-        self.0
+        unsupported()
     }
 
     pub fn accessed(&self) -> io::Result<SystemTime> {
-        self.0
+        unsupported()
     }
 
     pub fn created(&self) -> io::Result<SystemTime> {
-        self.0
+        unsupported()
-    }
-}
-
-impl Clone for FileAttr {
-    fn clone(&self) -> FileAttr {
-        self.0
     }
 }
 
@@ -64,28 +69,17 @@ impl FilePermissions {
         self.0
     }
 
-    pub fn set_readonly(&mut self, _readonly: bool) {
+    pub fn set_readonly(&mut self, readonly: bool) {
-        self.0
+        self.0 = readonly
-    }
     }
 
-impl Clone for FilePermissions {
+    const fn from_attr(attr: u64) -> Self {
-    fn clone(&self) -> FilePermissions {
+        Self(attr & r_efi::protocols::file::READ_ONLY != 0)
-        self.0
-    }
     }
 
-impl PartialEq for FilePermissions {
+    #[expect(dead_code)]
-    fn eq(&self, _other: &FilePermissions) -> bool {
+    const fn to_attr(&self) -> u64 {
-        self.0
+        if self.0 { r_efi::protocols::file::READ_ONLY } else { 0 }
-    }
-}
-
-impl Eq for FilePermissions {}
-
-impl fmt::Debug for FilePermissions {
-    fn fmt(&self, _f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        self.0
     }
 }
 
@@ -100,39 +94,16 @@ impl FileType {
     }
 
     pub fn is_file(&self) -> bool {
-        self.0
+        !self.is_dir()
     }
 
+    // Symlinks are not supported in UEFI
     pub fn is_symlink(&self) -> bool {
-        self.0
+        false
-    }
     }
 
-impl Clone for FileType {
+    const fn from_attr(attr: u64) -> Self {
-    fn clone(&self) -> FileType {
+        Self(attr & r_efi::protocols::file::DIRECTORY != 0)
-        self.0
-    }
-}
-
-impl Copy for FileType {}
-
-impl PartialEq for FileType {
-    fn eq(&self, _other: &FileType) -> bool {
-        self.0
-    }
-}
-
-impl Eq for FileType {}
-
-impl Hash for FileType {
-    fn hash<H: Hasher>(&self, _h: &mut H) {
-        self.0
-    }
-}
-
-impl fmt::Debug for FileType {
-    fn fmt(&self, _f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        self.0
     }
 }
 
@@ -303,8 +274,8 @@ pub fn rename(_old: &Path, _new: &Path) -> io::Result<()> {
     unsupported()
 }
 
-pub fn set_perm(_p: &Path, perm: FilePermissions) -> io::Result<()> {
+pub fn set_perm(_p: &Path, _perm: FilePermissions) -> io::Result<()> {
-    match perm.0 {}
+    unsupported()
 }
 
 pub fn rmdir(_p: &Path) -> io::Result<()> {

src/bootstrap/src/core/build_steps/compile.rs

@@ -194,11 +194,7 @@ impl Step for Std {
         trace!(?compiler_to_use);
 
         if compiler_to_use != compiler {
-            trace!(
+            trace!(?compiler_to_use, ?compiler, "compiler != compiler_to_use, uplifting library");
-                ?compiler_to_use,
-                ?compiler,
-                "compiler != compiler_to_use, handling cross-compile scenario"
-            );
 
             builder.ensure(Std::new(compiler_to_use, target));
             let msg = if compiler_to_use.host == target {

src/bootstrap/src/core/builder/cargo.rs

@@ -1045,8 +1045,11 @@ impl Builder<'_> {
         // so this line allows the use of custom libcs.
         cargo.env("LIBC_CHECK_CFG", "1");
 
-        if source_type == SourceType::InTree {
         let mut lint_flags = Vec::new();
+
+        // Lints for all in-tree code: compiler, rustdoc, cranelift, gcc,
+        // clippy, rustfmt, rust-analyzer, etc.
+        if source_type == SourceType::InTree {
             // When extending this list, add the new lints to the RUSTFLAGS of the
             // build_bootstrap function of src/bootstrap/bootstrap.py as well as
             // some code doesn't go through this `rustc` wrapper.
@@ -1058,28 +1061,33 @@ impl Builder<'_> {
                 rustdocflags.arg("-Dwarnings");
             }
 
-            // This does not use RUSTFLAGS due to caching issues with Cargo.
-            // Clippy is treated as an "in tree" tool, but shares the same
-            // cache as other "submodule" tools. With these options set in
-            // RUSTFLAGS, that causes *every* shared dependency to be rebuilt.
-            // By injecting this into the rustc wrapper, this circumvents
-            // Cargo's fingerprint detection. This is fine because lint flags
-            // are always ignored in dependencies. Eventually this should be
-            // fixed via better support from Cargo.
-            cargo.env("RUSTC_LINT_FLAGS", lint_flags.join(" "));
-
             rustdocflags.arg("-Wrustdoc::invalid_codeblock_attributes");
         }
 
+        // Lints just for `compiler/` crates.
         if mode == Mode::Rustc {
-            rustflags.arg("-Wrustc::internal");
+            lint_flags.push("-Wrustc::internal");
-            rustflags.arg("-Drustc::symbol_intern_string_literal");
+            lint_flags.push("-Drustc::symbol_intern_string_literal");
             // FIXME(edition_2024): Change this to `-Wrust_2024_idioms` when all
             // of the individual lints are satisfied.
-            rustflags.arg("-Wkeyword_idents_2024");
+            lint_flags.push("-Wkeyword_idents_2024");
-            rustflags.arg("-Wunsafe_op_in_unsafe_fn");
+            lint_flags.push("-Wunreachable_pub");
+            lint_flags.push("-Wunsafe_op_in_unsafe_fn");
         }
 
+        // This does not use RUSTFLAGS for two reasons.
+        // - Due to caching issues with Cargo. Clippy is treated as an "in
+        //   tree" tool, but shares the same cache as other "submodule" tools.
+        //   With these options set in RUSTFLAGS, that causes *every* shared
+        //   dependency to be rebuilt. By injecting this into the rustc
+        //   wrapper, this circumvents Cargo's fingerprint detection. This is
+        //   fine because lint flags are always ignored in dependencies.
+        //   Eventually this should be fixed via better support from Cargo.
+        // - RUSTFLAGS is ignored for proc macro crates that are being built on
+        //   the host (because `--target` is given). But we want the lint flags
+        //   to be applied to proc macro crates.
+        cargo.env("RUSTC_LINT_FLAGS", lint_flags.join(" "));
+
         if self.config.rust_frame_pointers {
             rustflags.arg("-Cforce-frame-pointers=true");
         }

src/tools/miri/tests/fail/intrinsics/copy_overlapping.rs

@@ -2,7 +2,7 @@
 
 // Directly call intrinsic to avoid debug assertions in libstd
 #[rustc_intrinsic]
-unsafe fn copy_nonoverlapping<T>(_src: *const T, _dst: *mut T, _count: usize);
+unsafe fn copy_nonoverlapping<T>(src: *const T, dst: *mut T, count: usize);
 
 fn main() {
     let mut data = [0u8; 16];

src/tools/miri/tests/fail/intrinsics/copy_unaligned.rs

@@ -2,7 +2,7 @@
 
 // Directly call intrinsic to avoid debug assertions in libstd
 #[rustc_intrinsic]
-unsafe fn copy_nonoverlapping<T>(_src: *const T, _dst: *mut T, _count: usize);
+unsafe fn copy_nonoverlapping<T>(src: *const T, dst: *mut T, count: usize);
 
 fn main() {
     let mut data = [0u16; 8];

src/tools/miri/tests/fail/intrinsics/ctlz_nonzero.rs

@@ -2,7 +2,7 @@
 
 mod rusti {
     #[rustc_intrinsic]
-    pub unsafe fn ctlz_nonzero<T>(_x: T) -> u32;
+    pub unsafe fn ctlz_nonzero<T>(x: T) -> u32;
 }
 
 pub fn main() {