Mark PartialEq as #[rustc_trivial_field_reads]

compiler/rustc_builtin_macros/src/format_foreign.rs

@@ -62,6 +62,8 @@ pub(crate) mod printf {
         /// Precision of the conversion.
         precision: Option<Num>,
         /// Length modifier for the conversion.
+        // FIXME(#143487): is it okay that this field is never read?
+        #[cfg_attr(not(bootstrap), expect(dead_code))]
         length: Option<&'a str>,
         /// Type of parameter being converted.
         type_: &'a str,

compiler/rustc_data_structures/src/sync/worker_local.rs

@@ -12,7 +12,13 @@ use crate::sync::CacheAligned;
 /// A pointer to the `RegistryData` which uniquely identifies a registry.
 /// This identifier can be reused if the registry gets freed.
 #[derive(Clone, Copy, PartialEq)]
-struct RegistryId(*const RegistryData);
+struct RegistryId(
+    #[cfg_attr(
+        not(bootstrap),
+        expect(dead_code, reason = "This field is only used for equality comparisons")
+    )]
+    *const RegistryData,
+);
 
 impl RegistryId {
     #[inline(always)]

compiler/rustc_errors/src/json/tests.rs

@@ -13,6 +13,7 @@ struct TestData {
 }
 
 #[derive(Deserialize, Debug, PartialEq, Eq)]
+#[allow(dead_code, reason = "Fields are only used for equality comparisons")]
 struct SpanTestData {
     pub byte_start: u32,
     pub byte_end: u32,

compiler/rustc_hir_typeck/src/loops.rs

@@ -26,15 +26,21 @@ use crate::errors::{
 enum Context {
     Normal,
     Fn,
-    Loop(hir::LoopSource),
+    Loop(
+        // FIXME(#143487): is it okay that this field is never read?
+        #[cfg_attr(not(bootstrap), expect(dead_code))] hir::LoopSource,
+    ),
     Closure(Span),
     Coroutine {
         coroutine_span: Span,
         kind: hir::CoroutineDesugaring,
         source: hir::CoroutineSource,
     },
     UnlabeledBlock(Span),
-    UnlabeledIfBlock(Span),
+    UnlabeledIfBlock(
+        // FIXME(#143487): is it okay that this field is never read?
+        #[cfg_attr(not(bootstrap), expect(dead_code))] Span,
+    ),
     LabeledBlock,
     /// E.g. The labeled block inside `['_'; 'block: { break 'block 1 + 2; }]`.
     AnonConst,

compiler/rustc_pattern_analysis/src/constructor.rs

@@ -657,7 +657,13 @@ impl Slice {
 
 /// A globally unique id to distinguish `Opaque` patterns.
 #[derive(Clone, Debug, PartialEq, Eq)]
-pub struct OpaqueId(u32);
+pub struct OpaqueId(
+    #[cfg_attr(
+        not(bootstrap),
+        expect(dead_code, reason = "This field is only used for equality comparisons")
+    )]
+    u32,
+);
 
 impl OpaqueId {
     pub fn new() -> Self {

compiler/rustc_thread_pool/tests/scoped_threadpool.rs

@@ -4,7 +4,7 @@ use crossbeam_utils::thread;
 use rustc_thread_pool::ThreadPoolBuilder;
 
 #[derive(PartialEq, Eq, Debug)]
-struct Local(i32);
+struct Local(#[allow(dead_code, reason = "Only used for equality comparisons")] i32);
 
 scoped_tls::scoped_thread_local!(static LOCAL: Local);
 

library/core/src/cmp.rs

@@ -247,6 +247,7 @@ use crate::ops::ControlFlow;
     append_const_msg
 )]
 #[rustc_diagnostic_item = "PartialEq"]
+#[rustc_trivial_field_reads]
 #[const_trait]
 #[rustc_const_unstable(feature = "const_trait_impl", issue = "67792")]
 pub trait PartialEq<Rhs: PointeeSized = Self>: PointeeSized {

library/stdarch/crates/std_detect/src/detect/os/linux/aarch64.rs

@@ -126,8 +126,8 @@ struct AtHwcap {
     f8fma: bool,
     f8dp4: bool,
     f8dp2: bool,
-    f8e4m3: bool,
-    f8e5m2: bool,
+    // f8e4m3: bool,
+    // f8e5m2: bool,
     smelutv2: bool,
     smef8f16: bool,
     smef8f32: bool,
@@ -230,8 +230,8 @@ impl From<auxvec::AuxVec> for AtHwcap {
             f8fma: bit::test(auxv.hwcap2, 52),
             f8dp4: bit::test(auxv.hwcap2, 53),
             f8dp2: bit::test(auxv.hwcap2, 54),
-            f8e4m3: bit::test(auxv.hwcap2, 55),
-            f8e5m2: bit::test(auxv.hwcap2, 56),
+            // f8e4m3: bit::test(auxv.hwcap2, 55),
+            // f8e5m2: bit::test(auxv.hwcap2, 56),
             smelutv2: bit::test(auxv.hwcap2, 57),
             smef8f16: bit::test(auxv.hwcap2, 58),
             smef8f32: bit::test(auxv.hwcap2, 59),

library/stdarch/crates/std_detect/src/detect/os/linux/s390x.rs

@@ -10,6 +10,8 @@ pub(crate) fn detect_features() -> cache::Initializer {
     cache(opt_hwcap, facilities)
 }
 
+// FIXME(#143487): is it okay that the fields are never read?
+#[expect(dead_code)]
 #[derive(Debug, Default, PartialEq)]
 struct AtHwcap {
     esan3: bool,

src/tools/miri/tests/fail/enum-untagged-variant-invalid-encoding.rs

@@ -7,6 +7,7 @@ use std::mem;
 // That means the untagged variants is in the niche variant range!
 // However, using the corresponding value (2+1 = 3) is not a valid encoding of this variant.
 #[derive(Copy, Clone, PartialEq)]
+#[allow(dead_code)]
 enum Foo {
     Var1,
     Var2(bool),

src/tools/miri/tests/pass/binops.rs

@@ -50,6 +50,7 @@ fn test_ptr() {
 }
 
 #[derive(PartialEq, Debug)]
+#[allow(dead_code)]
 struct P {
     x: isize,
     y: isize,

src/tools/miri/tests/pass/coercions.rs

@@ -1,4 +1,5 @@
 #![feature(coerce_unsized, unsize)]
+#![allow(dead_code)]
 
 use std::marker::Unsize;
 use std::ops::CoerceUnsized;

src/tools/miri/tests/pass/deriving-associated-types.rs

@@ -1,3 +1,5 @@
+#![allow(dead_code)]
+
 pub trait DeclaredTrait {
     type Type;
 }

src/tools/miri/tests/pass/tuple_like_enum_variant_constructor_struct_pointer_opt.rs

@@ -1,3 +1,5 @@
+#![allow(dead_code)]
+
 #[derive(Copy, Clone, PartialEq, Debug)]
 struct A<'a> {
     x: i32,

src/tools/miri/tests/pass/tuple_like_struct_constructor.rs

@@ -1,5 +1,6 @@
 fn main() {
     #[derive(PartialEq, Eq, Debug)]
+    #[allow(dead_code)]
     struct A(i32);
     assert_eq!(Some(42).map(A), Some(A(42)));
 }

src/tools/rust-analyzer/crates/hir-def/src/hir/format_args.rs

@@ -160,9 +160,12 @@ pub enum FormatArgumentKind {
 
 // Only used in parse_args and report_invalid_references,
 // to indicate how a referred argument was used.
-#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+#[derive(Clone, Copy, Debug)]
 enum PositionUsedAs {
-    Placeholder(Option<TextRange>),
+    Placeholder(
+        // FIXME(#143487): is it okay that the field is never read?
+        #[allow(dead_code)] Option<TextRange>,
+    ),
     Precision,
     Width,
 }

src/tools/rust-analyzer/crates/hir-ty/src/diagnostics/match_check.rs

@@ -65,6 +65,8 @@ pub(crate) enum PatKind {
     /// `Foo(...)` or `Foo{...}` or `Foo`, where `Foo` is a variant name from an ADT with
     /// multiple variants.
     Variant {
+        // FIXME(#143487): is it okay that the field is never read?
+        #[allow(dead_code)]
         substs: Substitution,
         enum_variant: EnumVariantId,
         subpatterns: Vec<FieldPat>,

src/tools/rust-analyzer/crates/hir-ty/src/infer/cast.rs

@@ -362,7 +362,10 @@ enum PointerKind {
     // slice
     Length,
     OfAlias,
-    OfParam(PlaceholderIndex),
+    OfParam(
+        // FIXME(#143487): is it okay that the field is never read?
+        #[allow(dead_code)] PlaceholderIndex,
+    ),
     Error,
 }
 

src/tools/rust-analyzer/crates/hir/src/lib.rs

@@ -4634,9 +4634,11 @@ impl Closure {
     }
 }
 
-#[derive(Clone, Debug, PartialEq, Eq)]
+#[derive(Clone, Debug)]
 pub struct ClosureCapture {
     owner: DefWithBodyId,
+    // FIXME(#143487): is it okay that the field is never read?
+    #[allow(dead_code)]
     closure: ClosureId,
     capture: hir_ty::CapturedItem,
 }

src/tools/rust-analyzer/crates/ide-completion/src/context.rs

@@ -287,6 +287,7 @@ pub(crate) struct PatternContext {
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub(crate) struct ParamContext {
     pub(crate) param_list: ast::ParamList,
+    #[allow(dead_code, reason = "Used for equality comparison")]
     pub(crate) param: ast::Param,
     pub(crate) kind: ParamKind,
 }

src/tools/rust-analyzer/xtask/src/publish/notes.rs

@@ -421,9 +421,15 @@ impl Default for ListNesting {
 
 #[derive(Debug, PartialEq, Eq)]
 enum ListMarker {
-    Asterisk(usize),
+    Asterisk(
+        // FIXME(#143487): is it okay that the field is never read?
+        #[allow(dead_code)] usize,
+    ),
     Hyphen,
-    Dot(usize),
+    Dot(
+        // FIXME(#143487): is it okay that the field is never read?
+        #[allow(dead_code)] usize,
+    ),
 }
 
 impl ListMarker {

tests/ui/abi/extern/extern-pass-FiveU16s.rs

@@ -1,5 +1,6 @@
 //@ run-pass
 #![allow(improper_ctypes)]
+#![allow(dead_code)]
 
 // Test a foreign function that accepts and returns a struct by value.
 

tests/ui/abi/extern/extern-pass-TwoU16s.rs

@@ -1,5 +1,6 @@
 //@ run-pass
 #![allow(improper_ctypes)]
+#![allow(dead_code)]
 
 // Test a foreign function that accepts and returns a struct
 // by value.

tests/ui/abi/extern/extern-pass-TwoU32s.rs

@@ -1,5 +1,6 @@
 //@ run-pass
 #![allow(improper_ctypes)]
+#![allow(dead_code)]
 
 // Test a foreign function that accepts and returns a struct
 // by value.

tests/ui/abi/extern/extern-pass-TwoU64s.rs

@@ -1,5 +1,6 @@
 //@ run-pass
 #![allow(improper_ctypes)]
+#![allow(dead_code)]
 
 // Test a foreign function that accepts and returns a struct
 // by value.

tests/ui/abi/extern/extern-pass-TwoU8s.rs

@@ -1,5 +1,6 @@
 //@ run-pass
 #![allow(improper_ctypes)]
+#![allow(dead_code)]
 
 // Test a foreign function that accepts and returns a struct
 // by value.

tests/ui/abi/homogenous-floats-target-feature-mixup.rs

@@ -9,6 +9,7 @@
 
 #![allow(overflowing_literals)]
 #![allow(unused_variables)]
+#![allow(dead_code)]
 
 use std::process::{Command, ExitStatus};
 use std::env;

tests/ui/async-await/drop-order/drop-order-for-async-fn-parameters-by-ref-binding.rs

@@ -3,6 +3,7 @@
 //@ run-pass
 
 #![allow(unused_variables)]
+#![allow(dead_code)]
 
 // Test that the drop order for parameters in a fn and async fn matches up. Also test that
 // parameters (used or unused) are not dropped until the async fn completes execution.

tests/ui/async-await/drop-order/drop-order-for-async-fn-parameters.rs

@@ -6,6 +6,7 @@
 //@[nomiropt]compile-flags: -Z mir-opt-level=0
 
 #![allow(unused_variables)]
+#![allow(dead_code)]
 
 // Test that the drop order for parameters in a fn and async fn matches up. Also test that
 // parameters (used or unused) are not dropped until the async fn completes execution.

tests/ui/async-await/drop-order/drop-order-for-locals-when-cancelled.rs

@@ -6,6 +6,7 @@
 #![allow(unused_variables)]
 #![allow(unused_must_use)]
 #![allow(path_statements)]
+#![allow(dead_code)]
 
 // Test that the drop order for locals in a fn and async fn matches up.
 extern crate arc_wake;

tests/ui/async-await/drop-order/drop-order-for-temporary-in-tail-return-expr.rs

@@ -6,6 +6,7 @@
 //@[nomiropt]compile-flags: -Z mir-opt-level=0
 
 #![allow(unused_variables)]
+#![allow(dead_code)]
 
 // Test the drop order for parameters relative to local variables and
 // temporaries created in the tail return expression of the function

tests/ui/async-await/drop-order/drop-order-when-cancelled.rs

@@ -10,6 +10,7 @@
 // This file is mostly copy-pasted from drop-order-for-async-fn-parameters.rs
 
 #![allow(unused_variables)]
+#![allow(dead_code)]
 
 extern crate arc_wake;
 

tests/ui/binding/match-larger-const.rs

@@ -1,4 +1,6 @@
 //@ run-pass
+#![allow(dead_code)]
+
 #[derive(Eq, PartialEq)]
 pub struct Data([u8; 4]);
 

tests/ui/binop/binops.rs

@@ -1,6 +1,7 @@
 //@ run-pass
 
 #![allow(non_camel_case_types)]
+#![allow(dead_code)]
 // Binop corner cases
 
 fn test_nil() {

tests/ui/codegen/mono-respects-abi-alignment.rs

@@ -8,6 +8,7 @@
 //! leading to incorrect method dispatch for `unwrap()`.
 
 //@ run-pass
+#![allow(dead_code)]
 
 #[derive(Copy, Clone)]
 struct S<T> {

tests/ui/coercion/issue-39823.rs

@@ -1,5 +1,6 @@
 //@ run-pass
 //@ aux-build:issue-39823.rs
+#![allow(dead_code)]
 
 extern crate issue_39823;
 use issue_39823::{RemoteC, RemoteG};

tests/ui/coherence/coherence-where-clause.rs

@@ -1,4 +1,5 @@
 //@ run-pass
+#![allow(dead_code)]
 
 use std::fmt::Debug;
 trait MyTrait {

tests/ui/consts/const_constructor/const_constructor_qpath.rs

@@ -1,4 +1,5 @@
 //@ run-pass
+#![allow(dead_code)]
 
 trait ConstDefault {
     const DEFAULT: Self;

tests/ui/consts/const_in_pattern/issue-62614.rs

@@ -1,4 +1,5 @@
 //@ run-pass
+#![allow(dead_code)]
 
 struct Sum(u32, u32);
 

tests/ui/consts/const_in_pattern/null-raw-ptr-issue-119270.rs

@@ -1,4 +1,5 @@
 //@ run-pass
+#![allow(dead_code)]
 struct NoDerive(#[allow(dead_code)] i32);
 
 #[derive(PartialEq)]

tests/ui/consts/match-const-fn-structs.rs

@@ -1,5 +1,6 @@
 //@ run-pass
 #![allow(unused_variables)]
+#![allow(dead_code)]
 
 // https://github.com/rust-lang/rust/issues/46114
 

tests/ui/deriving/deriving-associated-types.rs

@@ -1,4 +1,6 @@
 //@ run-pass
+#![allow(dead_code)]
+
 pub trait DeclaredTrait {
     type Type;
 }

tests/ui/deriving/deriving-via-extension-struct-tuple.rs

@@ -1,4 +1,5 @@
 //@ run-pass
+#![allow(dead_code)]
 #[derive(PartialEq, Debug)]
 struct Foo(isize, isize, String);
 

tests/ui/deriving/deriving-via-extension-struct.rs

@@ -1,4 +1,6 @@
 //@ run-pass
+#![allow(dead_code)]
+
 #[derive(PartialEq, Debug)]
 struct Foo {
     x: isize,