Auto merge of #133893 - fmease:rollup-11pi6fg, r=fmease

Rollup of 10 pull requests

Successful merges:

 - #118833 (Add lint against function pointer comparisons)
 - #122161 (Fix suggestion when shorthand `self` has erroneous type)
 - #133233 (Add context to "const in pattern" errors)
 - #133761 (Update books)
 - #133843 (Do not emit empty suggestion)
 - #133863 (Rename `core_pattern_type` and `core_pattern_types` lib feature  gates to `pattern_type_macro`)
 - #133872 (No need to create placeholders for GAT args in confirm_object_candidate)
 - #133874 (`fn_sig_for_fn_abi` should return a `ty::FnSig`, no need for a binder)
 - #133890 (Add a new test ui/incoherent-inherent-impls/no-other-unrelated-errors to check E0116 does not cause unrelated errors)
 - #133892 (Revert #133817)

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

compiler/rustc_ast/src/ast.rs

@@ -2566,6 +2566,18 @@ pub enum SelfKind {
     Explicit(P<Ty>, Mutability),
 }
 
+impl SelfKind {
+    pub fn to_ref_suggestion(&self) -> String {
+        match self {
+            SelfKind::Region(None, mutbl) => mutbl.ref_prefix_str().to_string(),
+            SelfKind::Region(Some(lt), mutbl) => format!("&{lt} {}", mutbl.prefix_str()),
+            SelfKind::Value(_) | SelfKind::Explicit(_, _) => {
+                unreachable!("if we had an explicit self, we wouldn't be here")
+            }
+        }
+    }
+}
+
 pub type ExplicitSelf = Spanned<SelfKind>;
 
 impl Param {

compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs

@@ -3394,7 +3394,13 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         let Some(ty) = self.node_ty_opt(tail_expr.hir_id) else {
             return;
         };
-        if self.can_eq(self.param_env, expected_ty, ty) {
+        if self.can_eq(self.param_env, expected_ty, ty)
+            // FIXME: this happens with macro calls. Need to figure out why the stmt
+            // `println!();` doesn't include the `;` in its `Span`. (#133845)
+            // We filter these out to avoid ICEs with debug assertions on caused by
+            // empty suggestions.
+            && stmt.span.hi() != tail_expr.span.hi()
+        {
             err.span_suggestion_short(
                 stmt.span.with_lo(tail_expr.span.hi()),
                 "remove this semicolon",

compiler/rustc_lint/messages.ftl

@@ -885,6 +885,12 @@ lint_unnameable_test_items = cannot test inner items
 lint_unnecessary_qualification = unnecessary qualification
     .suggestion = remove the unnecessary path segments
 
+lint_unpredictable_fn_pointer_comparisons = function pointer comparisons do not produce meaningful results since their addresses are not guaranteed to be unique
+    .note_duplicated_fn = the address of the same function can vary between different codegen units
+    .note_deduplicated_fn = furthermore, different functions could have the same address after being merged together
+    .note_visit_fn_addr_eq = for more information visit <https://doc.rust-lang.org/nightly/core/ptr/fn.fn_addr_eq.html>
+    .fn_addr_eq_suggestion = refactor your code, or use `std::ptr::fn_addr_eq` to suppress the lint
+
 lint_unqualified_local_imports = `use` of a local item without leading `self::`, `super::`, or `crate::`
 
 lint_unsafe_attr_outside_unsafe = unsafe attribute used without unsafe

compiler/rustc_lint/src/lints.rs

@@ -1815,6 +1815,42 @@ pub(crate) enum AmbiguousWidePointerComparisonsAddrSuggestion<'a> {
     },
 }
 
+#[derive(LintDiagnostic)]
+pub(crate) enum UnpredictableFunctionPointerComparisons<'a> {
+    #[diag(lint_unpredictable_fn_pointer_comparisons)]
+    #[note(lint_note_duplicated_fn)]
+    #[note(lint_note_deduplicated_fn)]
+    #[note(lint_note_visit_fn_addr_eq)]
+    Suggestion {
+        #[subdiagnostic]
+        sugg: UnpredictableFunctionPointerComparisonsSuggestion<'a>,
+    },
+    #[diag(lint_unpredictable_fn_pointer_comparisons)]
+    #[note(lint_note_duplicated_fn)]
+    #[note(lint_note_deduplicated_fn)]
+    #[note(lint_note_visit_fn_addr_eq)]
+    Warn,
+}
+
+#[derive(Subdiagnostic)]
+#[multipart_suggestion(
+    lint_fn_addr_eq_suggestion,
+    style = "verbose",
+    applicability = "maybe-incorrect"
+)]
+pub(crate) struct UnpredictableFunctionPointerComparisonsSuggestion<'a> {
+    pub ne: &'a str,
+    pub cast_right: String,
+    pub deref_left: &'a str,
+    pub deref_right: &'a str,
+    #[suggestion_part(code = "{ne}std::ptr::fn_addr_eq({deref_left}")]
+    pub left: Span,
+    #[suggestion_part(code = ", {deref_right}")]
+    pub middle: Span,
+    #[suggestion_part(code = "{cast_right})")]
+    pub right: Span,
+}
+
 pub(crate) struct ImproperCTypes<'a> {
     pub ty: Ty<'a>,
     pub desc: &'a str,

compiler/rustc_lint/src/types.rs

@@ -23,7 +23,9 @@ use crate::lints::{
     AmbiguousWidePointerComparisons, AmbiguousWidePointerComparisonsAddrMetadataSuggestion,
     AmbiguousWidePointerComparisonsAddrSuggestion, AtomicOrderingFence, AtomicOrderingLoad,
     AtomicOrderingStore, ImproperCTypes, InvalidAtomicOrderingDiag, InvalidNanComparisons,
-    InvalidNanComparisonsSuggestion, UnusedComparisons, VariantSizeDifferencesDiag,
+    InvalidNanComparisonsSuggestion, UnpredictableFunctionPointerComparisons,
+    UnpredictableFunctionPointerComparisonsSuggestion, UnusedComparisons,
+    VariantSizeDifferencesDiag,
 };
 use crate::{LateContext, LateLintPass, LintContext, fluent_generated as fluent};
 
@@ -166,6 +168,35 @@ declare_lint! {
     "detects ambiguous wide pointer comparisons"
 }
 
+declare_lint! {
+    /// The `unpredictable_function_pointer_comparisons` lint checks comparison
+    /// of function pointer as the operands.
+    ///
+    /// ### Example
+    ///
+    /// ```rust
+    /// fn a() {}
+    /// fn b() {}
+    ///
+    /// let f: fn() = a;
+    /// let g: fn() = b;
+    ///
+    /// let _ = f == g;
+    /// ```
+    ///
+    /// {{produces}}
+    ///
+    /// ### Explanation
+    ///
+    /// Function pointers comparisons do not produce meaningful result since
+    /// they are never guaranteed to be unique and could vary between different
+    /// code generation units. Furthermore, different functions could have the
+    /// same address after being merged together.
+    UNPREDICTABLE_FUNCTION_POINTER_COMPARISONS,
+    Warn,
+    "detects unpredictable function pointer comparisons"
+}
+
 #[derive(Copy, Clone, Default)]
 pub(crate) struct TypeLimits {
     /// Id of the last visited negated expression
@@ -178,7 +209,8 @@ impl_lint_pass!(TypeLimits => [
     UNUSED_COMPARISONS,
     OVERFLOWING_LITERALS,
     INVALID_NAN_COMPARISONS,
-    AMBIGUOUS_WIDE_POINTER_COMPARISONS
+    AMBIGUOUS_WIDE_POINTER_COMPARISONS,
+    UNPREDICTABLE_FUNCTION_POINTER_COMPARISONS
 ]);
 
 impl TypeLimits {
@@ -255,7 +287,7 @@ fn lint_nan<'tcx>(
     cx.emit_span_lint(INVALID_NAN_COMPARISONS, e.span, lint);
 }
 
-#[derive(Debug, PartialEq)]
+#[derive(Debug, PartialEq, Copy, Clone)]
 enum ComparisonOp {
     BinOp(hir::BinOpKind),
     Other,
@@ -383,6 +415,100 @@ fn lint_wide_pointer<'tcx>(
     );
 }
 
+fn lint_fn_pointer<'tcx>(
+    cx: &LateContext<'tcx>,
+    e: &'tcx hir::Expr<'tcx>,
+    cmpop: ComparisonOp,
+    l: &'tcx hir::Expr<'tcx>,
+    r: &'tcx hir::Expr<'tcx>,
+) {
+    let peel_refs = |mut ty: Ty<'tcx>| -> (Ty<'tcx>, usize) {
+        let mut refs = 0;
+
+        while let ty::Ref(_, inner_ty, _) = ty.kind() {
+            ty = *inner_ty;
+            refs += 1;
+        }
+
+        (ty, refs)
+    };
+
+    // Left and right operands can have borrows, remove them
+    let l = l.peel_borrows();
+    let r = r.peel_borrows();
+
+    let Some(l_ty) = cx.typeck_results().expr_ty_opt(l) else { return };
+    let Some(r_ty) = cx.typeck_results().expr_ty_opt(r) else { return };
+
+    // Remove any references as `==` will deref through them (and count the
+    // number of references removed, for latter).
+    let (l_ty, l_ty_refs) = peel_refs(l_ty);
+    let (r_ty, r_ty_refs) = peel_refs(r_ty);
+
+    if !l_ty.is_fn() || !r_ty.is_fn() {
+        return;
+    }
+
+    // Let's try to suggest `ptr::fn_addr_eq` if/when possible.
+
+    let is_eq_ne = matches!(cmpop, ComparisonOp::BinOp(hir::BinOpKind::Eq | hir::BinOpKind::Ne));
+
+    if !is_eq_ne {
+        // Neither `==` nor `!=`, we can't suggest `ptr::fn_addr_eq`, just show the warning.
+        return cx.emit_span_lint(
+            UNPREDICTABLE_FUNCTION_POINTER_COMPARISONS,
+            e.span,
+            UnpredictableFunctionPointerComparisons::Warn,
+        );
+    }
+
+    let (Some(l_span), Some(r_span)) =
+        (l.span.find_ancestor_inside(e.span), r.span.find_ancestor_inside(e.span))
+    else {
+        // No appropriate spans for the left and right operands, just show the warning.
+        return cx.emit_span_lint(
+            UNPREDICTABLE_FUNCTION_POINTER_COMPARISONS,
+            e.span,
+            UnpredictableFunctionPointerComparisons::Warn,
+        );
+    };
+
+    let ne = if cmpop == ComparisonOp::BinOp(hir::BinOpKind::Ne) { "!" } else { "" };
+
+    // `ptr::fn_addr_eq` only works with raw pointer, deref any references.
+    let deref_left = &*"*".repeat(l_ty_refs);
+    let deref_right = &*"*".repeat(r_ty_refs);
+
+    let left = e.span.shrink_to_lo().until(l_span.shrink_to_lo());
+    let middle = l_span.shrink_to_hi().until(r_span.shrink_to_lo());
+    let right = r_span.shrink_to_hi().until(e.span.shrink_to_hi());
+
+    // We only check for a right cast as `FnDef` == `FnPtr` is not possible,
+    // only `FnPtr == FnDef` is possible.
+    let cast_right = if !r_ty.is_fn_ptr() {
+        let fn_sig = r_ty.fn_sig(cx.tcx);
+        format!(" as {fn_sig}")
+    } else {
+        String::new()
+    };
+
+    cx.emit_span_lint(
+        UNPREDICTABLE_FUNCTION_POINTER_COMPARISONS,
+        e.span,
+        UnpredictableFunctionPointerComparisons::Suggestion {
+            sugg: UnpredictableFunctionPointerComparisonsSuggestion {
+                ne,
+                deref_left,
+                deref_right,
+                left,
+                middle,
+                right,
+                cast_right,
+            },
+        },
+    );
+}
+
 impl<'tcx> LateLintPass<'tcx> for TypeLimits {
     fn check_expr(&mut self, cx: &LateContext<'tcx>, e: &'tcx hir::Expr<'tcx>) {
         match e.kind {
@@ -399,7 +525,9 @@ impl<'tcx> LateLintPass<'tcx> for TypeLimits {
                         cx.emit_span_lint(UNUSED_COMPARISONS, e.span, UnusedComparisons);
                     } else {
                         lint_nan(cx, e, binop, l, r);
-                        lint_wide_pointer(cx, e, ComparisonOp::BinOp(binop.node), l, r);
+                        let cmpop = ComparisonOp::BinOp(binop.node);
+                        lint_wide_pointer(cx, e, cmpop, l, r);
+                        lint_fn_pointer(cx, e, cmpop, l, r);
                     }
                 }
             }
@@ -411,6 +539,7 @@ impl<'tcx> LateLintPass<'tcx> for TypeLimits {
                     && let Some(cmpop) = diag_item_cmpop(diag_item) =>
             {
                 lint_wide_pointer(cx, e, cmpop, l, r);
+                lint_fn_pointer(cx, e, cmpop, l, r);
             }
             hir::ExprKind::MethodCall(_, l, [r], _)
                 if let Some(def_id) = cx.typeck_results().type_dependent_def_id(e.hir_id)
@@ -418,6 +547,7 @@ impl<'tcx> LateLintPass<'tcx> for TypeLimits {
                     && let Some(cmpop) = diag_item_cmpop(diag_item) =>
             {
                 lint_wide_pointer(cx, e, cmpop, l, r);
+                lint_fn_pointer(cx, e, cmpop, l, r);
             }
             _ => {}
         };

compiler/rustc_mir_build/messages.ftl

@@ -84,12 +84,17 @@ mir_build_call_to_unsafe_fn_requires_unsafe_unsafe_op_in_unsafe_fn_allowed =
 
 mir_build_confused = missing patterns are not covered because `{$variable}` is interpreted as a constant pattern, not a new variable
 
-mir_build_const_param_in_pattern = const parameters cannot be referenced in patterns
+mir_build_const_defined_here = constant defined here
 
-mir_build_const_pattern_depends_on_generic_parameter =
-    constant pattern depends on a generic parameter
+mir_build_const_param_in_pattern = constant parameters cannot be referenced in patterns
+    .label = can't be used in patterns
+mir_build_const_param_in_pattern_def = constant defined here
+
+mir_build_const_pattern_depends_on_generic_parameter = constant pattern cannot depend on generic parameters
+    .label = `const` depends on a generic parameter
 
 mir_build_could_not_eval_const_pattern = could not evaluate constant pattern
+    .label = could not evaluate constant
 
 mir_build_deref_raw_pointer_requires_unsafe =
     dereference of raw pointer is unsafe and requires unsafe block
@@ -147,7 +152,8 @@ mir_build_inline_assembly_requires_unsafe_unsafe_op_in_unsafe_fn_allowed =
 
 mir_build_interpreted_as_const = introduce a variable instead
 
-mir_build_invalid_pattern = `{$non_sm_ty}` cannot be used in patterns
+mir_build_invalid_pattern = {$prefix} `{$non_sm_ty}` cannot be used in patterns
+    .label = {$prefix} can't be used in patterns
 
 mir_build_irrefutable_let_patterns_if_let = irrefutable `if let` {$count ->
         [one] pattern
@@ -244,10 +250,12 @@ mir_build_mutation_of_layout_constrained_field_requires_unsafe_unsafe_op_in_unsa
     .label = mutation of layout constrained field
 
 mir_build_nan_pattern = cannot use NaN in patterns
+    .label = evaluates to `NaN`, which is not allowed in patterns
     .note = NaNs compare inequal to everything, even themselves, so this pattern would never match
     .help = try using the `is_nan` method instead
 
 mir_build_non_const_path = runtime values cannot be referenced in patterns
+    .label = references a runtime value
 
 mir_build_non_empty_never_pattern =
     mismatched types
@@ -265,13 +273,15 @@ mir_build_non_exhaustive_patterns_type_not_empty = non-exhaustive patterns: type
     .suggestion = ensure that all possible cases are being handled by adding a match arm with a wildcard pattern as shown
     .help = ensure that all possible cases are being handled by adding a match arm with a wildcard pattern
 
-mir_build_non_partial_eq_match =
-    to use a constant of type `{$non_peq_ty}` in a pattern, the type must implement `PartialEq`
+mir_build_non_partial_eq_match = constant of non-structural type `{$ty}` in a pattern
+    .label = constant of non-structural type
 
 mir_build_pattern_not_covered = refutable pattern in {$origin}
     .pattern_ty = the matched value is of type `{$pattern_ty}`
 
-mir_build_pointer_pattern = function pointers and raw pointers not derived from integers in patterns behave unpredictably and should not be relied upon. See https://github.com/rust-lang/rust/issues/70861 for details.
+mir_build_pointer_pattern = function pointers and raw pointers not derived from integers in patterns behave unpredictably and should not be relied upon
+    .label = can't be used in patterns
+    .note = see https://github.com/rust-lang/rust/issues/70861 for details
 
 mir_build_privately_uninhabited = pattern `{$witness_1}` is currently uninhabited, but this variant contains private fields which may become inhabited in the future
 
@@ -283,6 +293,8 @@ mir_build_rustc_box_attribute_error = `#[rustc_box]` attribute used incorrectly
     .missing_box = `#[rustc_box]` requires the `owned_box` lang item
 
 mir_build_static_in_pattern = statics cannot be referenced in patterns
+    .label = can't be used in patterns
+mir_build_static_in_pattern_def = `static` defined here
 
 mir_build_suggest_attempted_int_lit = alternatively, you could prepend the pattern with an underscore to define a new named variable; identifiers cannot begin with digits
 
@@ -310,12 +322,12 @@ mir_build_trailing_irrefutable_let_patterns = trailing irrefutable {$count ->
         *[other] them
     } into the body
 
-mir_build_type_not_structural =
-     to use a constant of type `{$non_sm_ty}` in a pattern, `{$non_sm_ty}` must be annotated with `#[derive(PartialEq)]`
-
+mir_build_type_not_structural = constant of non-structural type `{$ty}` in a pattern
+    .label = constant of non-structural type
+mir_build_type_not_structural_def = `{$ty}` must be annotated with `#[derive(PartialEq)]` to be usable in patterns
 mir_build_type_not_structural_more_info = see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
-
-mir_build_type_not_structural_tip = the traits must be derived, manual `impl`s are not sufficient
+mir_build_type_not_structural_tip =
+    the `PartialEq` trait must be derived, manual `impl`s are not sufficient; see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
 
 mir_build_unconditional_recursion = function cannot return without recursing
     .label = cannot return without recursing
@@ -334,6 +346,7 @@ mir_build_union_field_requires_unsafe_unsafe_op_in_unsafe_fn_allowed =
     .label = access to union field
 
 mir_build_union_pattern = cannot use unions in constant patterns
+    .label = can't use a `union` here
 
 mir_build_unreachable_making_this_unreachable = collectively making this unreachable
 

compiler/rustc_mir_build/src/errors.rs

@@ -631,20 +631,27 @@ pub(crate) struct NonExhaustiveMatchAllArmsGuarded;
 #[diag(mir_build_static_in_pattern, code = E0158)]
 pub(crate) struct StaticInPattern {
     #[primary_span]
+    #[label]
     pub(crate) span: Span,
+    #[label(mir_build_static_in_pattern_def)]
+    pub(crate) static_span: Span,
 }
 
 #[derive(Diagnostic)]
 #[diag(mir_build_const_param_in_pattern, code = E0158)]
 pub(crate) struct ConstParamInPattern {
     #[primary_span]
+    #[label]
     pub(crate) span: Span,
+    #[label(mir_build_const_param_in_pattern_def)]
+    pub(crate) const_span: Span,
 }
 
 #[derive(Diagnostic)]
 #[diag(mir_build_non_const_path, code = E0080)]
 pub(crate) struct NonConstPath {
     #[primary_span]
+    #[label]
     pub(crate) span: Span,
 }
 
@@ -695,6 +702,7 @@ pub(crate) struct WantedConstant {
 #[diag(mir_build_const_pattern_depends_on_generic_parameter, code = E0158)]
 pub(crate) struct ConstPatternDependsOnGenericParameter {
     #[primary_span]
+    #[label]
     pub(crate) span: Span,
 }
 
@@ -702,6 +710,7 @@ pub(crate) struct ConstPatternDependsOnGenericParameter {
 #[diag(mir_build_could_not_eval_const_pattern)]
 pub(crate) struct CouldNotEvalConstPattern {
     #[primary_span]
+    #[label]
     pub(crate) span: Span,
 }
 
@@ -867,33 +876,43 @@ pub(crate) enum Conflict {
 #[diag(mir_build_union_pattern)]
 pub(crate) struct UnionPattern {
     #[primary_span]
+    #[label]
     pub(crate) span: Span,
 }
 
 #[derive(Diagnostic)]
 #[diag(mir_build_type_not_structural)]
-#[note(mir_build_type_not_structural_tip)]
-#[note(mir_build_type_not_structural_more_info)]
 pub(crate) struct TypeNotStructural<'tcx> {
     #[primary_span]
+    #[label]
     pub(crate) span: Span,
-    pub(crate) non_sm_ty: Ty<'tcx>,
+    #[label(mir_build_type_not_structural_def)]
+    pub(crate) ty_def_span: Span,
+    pub(crate) ty: Ty<'tcx>,
+    #[note(mir_build_type_not_structural_tip)]
+    pub(crate) manual_partialeq_impl_span: Option<Span>,
+    #[note(mir_build_type_not_structural_more_info)]
+    pub(crate) manual_partialeq_impl_note: bool,
 }
 
 #[derive(Diagnostic)]
 #[diag(mir_build_non_partial_eq_match)]
+#[note(mir_build_type_not_structural_more_info)]
 pub(crate) struct TypeNotPartialEq<'tcx> {
     #[primary_span]
+    #[label]
     pub(crate) span: Span,
-    pub(crate) non_peq_ty: Ty<'tcx>,
+    pub(crate) ty: Ty<'tcx>,
 }
 
 #[derive(Diagnostic)]
 #[diag(mir_build_invalid_pattern)]
 pub(crate) struct InvalidPattern<'tcx> {
     #[primary_span]
+    #[label]
     pub(crate) span: Span,
     pub(crate) non_sm_ty: Ty<'tcx>,
+    pub(crate) prefix: String,
 }
 
 #[derive(Diagnostic)]
@@ -910,13 +929,16 @@ pub(crate) struct UnsizedPattern<'tcx> {
 #[help]
 pub(crate) struct NaNPattern {
     #[primary_span]
+    #[label]
     pub(crate) span: Span,
 }
 
 #[derive(Diagnostic)]
 #[diag(mir_build_pointer_pattern)]
+#[note]
 pub(crate) struct PointerPattern {
     #[primary_span]
+    #[label]
     pub(crate) span: Span,
 }
 

compiler/rustc_mir_build/src/thir/pattern/const_to_pat.rs

@@ -1,14 +1,17 @@
 use rustc_abi::{FieldIdx, VariantIdx};
 use rustc_apfloat::Float;
+use rustc_data_structures::fx::FxHashSet;
+use rustc_errors::Diag;
 use rustc_hir as hir;
 use rustc_index::Idx;
 use rustc_infer::infer::TyCtxtInferExt;
 use rustc_infer::traits::Obligation;
 use rustc_middle::mir::interpret::ErrorHandled;
 use rustc_middle::thir::{FieldPat, Pat, PatKind};
-use rustc_middle::ty::{self, Ty, TyCtxt, TypeVisitableExt, ValTree};
+use rustc_middle::ty::{self, Ty, TyCtxt, TypeVisitableExt, TypeVisitor, ValTree};
 use rustc_middle::{mir, span_bug};
-use rustc_span::Span;
+use rustc_span::def_id::DefId;
+use rustc_span::{Span, sym};
 use rustc_trait_selection::traits::ObligationCause;
 use rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt;
 use tracing::{debug, instrument, trace};
@@ -35,7 +38,7 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> {
         id: hir::HirId,
         span: Span,
     ) -> Box<Pat<'tcx>> {
-        let mut convert = ConstToPat::new(self, id, span);
+        let mut convert = ConstToPat::new(self, id, span, c);
 
         match c.kind() {
             ty::ConstKind::Unevaluated(uv) => convert.unevaluated_to_pat(uv, ty),
@@ -49,21 +52,26 @@ struct ConstToPat<'tcx> {
     tcx: TyCtxt<'tcx>,
     typing_env: ty::TypingEnv<'tcx>,
     span: Span,
+    id: hir::HirId,
 
     treat_byte_string_as_slice: bool,
+
+    c: ty::Const<'tcx>,
 }
 
 impl<'tcx> ConstToPat<'tcx> {
-    fn new(pat_ctxt: &PatCtxt<'_, 'tcx>, id: hir::HirId, span: Span) -> Self {
+    fn new(pat_ctxt: &PatCtxt<'_, 'tcx>, id: hir::HirId, span: Span, c: ty::Const<'tcx>) -> Self {
         trace!(?pat_ctxt.typeck_results.hir_owner);
         ConstToPat {
             tcx: pat_ctxt.tcx,
             typing_env: pat_ctxt.typing_env,
             span,
+            id,
             treat_byte_string_as_slice: pat_ctxt
                 .typeck_results
                 .treat_byte_string_as_slice
                 .contains(&id.local_id),
+            c,
         }
     }
 
@@ -71,13 +79,32 @@ impl<'tcx> ConstToPat<'tcx> {
         ty.is_structural_eq_shallow(self.tcx)
     }
 
+    /// We errored. Signal that in the pattern, so that follow up errors can be silenced.
+    fn mk_err(&self, mut err: Diag<'_>, ty: Ty<'tcx>) -> Box<Pat<'tcx>> {
+        if let ty::ConstKind::Unevaluated(uv) = self.c.kind() {
+            let def_kind = self.tcx.def_kind(uv.def);
+            if let hir::def::DefKind::AssocConst = def_kind
+                && let Some(def_id) = uv.def.as_local()
+            {
+                // Include the container item in the output.
+                err.span_label(self.tcx.def_span(self.tcx.local_parent(def_id)), "");
+            }
+            if let hir::def::DefKind::Const | hir::def::DefKind::AssocConst = def_kind {
+                err.span_label(
+                    self.tcx.def_span(uv.def),
+                    crate::fluent_generated::mir_build_const_defined_here,
+                );
+            }
+        }
+        Box::new(Pat { span: self.span, ty, kind: PatKind::Error(err.emit()) })
+    }
+
     fn unevaluated_to_pat(
         &mut self,
         uv: ty::UnevaluatedConst<'tcx>,
         ty: Ty<'tcx>,
     ) -> Box<Pat<'tcx>> {
         trace!(self.treat_byte_string_as_slice);
-        let pat_from_kind = |kind| Box::new(Pat { span: self.span, ty, kind });
 
         // It's not *technically* correct to be revealing opaque types here as borrowcheck has
         // not run yet. However, CTFE itself uses `TypingMode::PostAnalysis` unconditionally even
@@ -96,32 +123,60 @@ impl<'tcx> ConstToPat<'tcx> {
             Ok(Ok(c)) => c,
             Err(ErrorHandled::Reported(_, _)) => {
                 // Let's tell the use where this failing const occurs.
-                let e = self.tcx.dcx().emit_err(CouldNotEvalConstPattern { span: self.span });
-                return pat_from_kind(PatKind::Error(e));
+                let mut err =
+                    self.tcx.dcx().create_err(CouldNotEvalConstPattern { span: self.span });
+                // We've emitted an error on the original const, it would be redundant to complain
+                // on its use as well.
+                if let ty::ConstKind::Unevaluated(uv) = self.c.kind()
+                    && let hir::def::DefKind::Const | hir::def::DefKind::AssocConst =
+                        self.tcx.def_kind(uv.def)
+                {
+                    err.downgrade_to_delayed_bug();
+                }
+                return self.mk_err(err, ty);
             }
             Err(ErrorHandled::TooGeneric(_)) => {
-                let e = self
+                let mut e = self
                     .tcx
                     .dcx()
-                    .emit_err(ConstPatternDependsOnGenericParameter { span: self.span });
-                return pat_from_kind(PatKind::Error(e));
+                    .create_err(ConstPatternDependsOnGenericParameter { span: self.span });
+                for arg in uv.args {
+                    if let ty::GenericArgKind::Type(ty) = arg.unpack()
+                        && let ty::Param(param_ty) = ty.kind()
+                    {
+                        let def_id = self.tcx.hir().enclosing_body_owner(self.id);
+                        let generics = self.tcx.generics_of(def_id);
+                        let param = generics.type_param(*param_ty, self.tcx);
+                        let span = self.tcx.def_span(param.def_id);
+                        e.span_label(span, "constant depends on this generic parameter");
+                        if let Some(ident) = self.tcx.def_ident_span(def_id)
+                            && self.tcx.sess.source_map().is_multiline(ident.between(span))
+                        {
+                            // Display the `fn` name as well in the diagnostic, as the generic isn't
+                            // in the same line and it could be confusing otherwise.
+                            e.span_label(ident, "");
+                        }
+                    }
+                }
+                return self.mk_err(e, ty);
             }
             Ok(Err(bad_ty)) => {
                 // The pattern cannot be turned into a valtree.
                 let e = match bad_ty.kind() {
                     ty::Adt(def, ..) => {
                         assert!(def.is_union());
-                        self.tcx.dcx().emit_err(UnionPattern { span: self.span })
+                        self.tcx.dcx().create_err(UnionPattern { span: self.span })
                     }
                     ty::FnPtr(..) | ty::RawPtr(..) => {
-                        self.tcx.dcx().emit_err(PointerPattern { span: self.span })
+                        self.tcx.dcx().create_err(PointerPattern { span: self.span })
                     }
-                    _ => self
-                        .tcx
-                        .dcx()
-                        .emit_err(InvalidPattern { span: self.span, non_sm_ty: bad_ty }),
+                    _ => self.tcx.dcx().create_err(InvalidPattern {
+                        span: self.span,
+                        non_sm_ty: bad_ty,
+                        prefix: bad_ty.prefix_string(self.tcx).to_string(),
+                    }),
                 };
-                return pat_from_kind(PatKind::Error(e));
+                return self.mk_err(e, ty);
             }
         };
 
@@ -130,42 +185,16 @@ impl<'tcx> ConstToPat<'tcx> {
 
         if !inlined_const_as_pat.references_error() {
             // Always check for `PartialEq` if we had no other errors yet.
-            if !self.type_has_partial_eq_impl(ty) {
-                let err = TypeNotPartialEq { span: self.span, non_peq_ty: ty };
-                let e = self.tcx.dcx().emit_err(err);
-                return pat_from_kind(PatKind::Error(e));
+            if !type_has_partial_eq_impl(self.tcx, typing_env, ty).0 {
+                let mut err = self.tcx.dcx().create_err(TypeNotPartialEq { span: self.span, ty });
+                extend_type_not_partial_eq(self.tcx, typing_env, ty, &mut err);
+                return self.mk_err(err, ty);
             }
         }
 
         inlined_const_as_pat
     }
 
-    #[instrument(level = "trace", skip(self), ret)]
-    fn type_has_partial_eq_impl(&self, ty: Ty<'tcx>) -> bool {
-        let (infcx, param_env) = self.tcx.infer_ctxt().build_with_typing_env(self.typing_env);
-        // double-check there even *is* a semantic `PartialEq` to dispatch to.
-        //
-        // (If there isn't, then we can safely issue a hard
-        // error, because that's never worked, due to compiler
-        // using `PartialEq::eq` in this scenario in the past.)
-        let partial_eq_trait_id =
-            self.tcx.require_lang_item(hir::LangItem::PartialEq, Some(self.span));
-        let partial_eq_obligation = Obligation::new(
-            self.tcx,
-            ObligationCause::dummy(),
-            param_env,
-            ty::TraitRef::new(self.tcx, partial_eq_trait_id, [ty, ty]),
-        );
-
-        // This *could* accept a type that isn't actually `PartialEq`, because region bounds get
-        // ignored. However that should be pretty much impossible since consts that do not depend on
-        // generics can only mention the `'static` lifetime, and how would one have a type that's
-        // `PartialEq` for some lifetime but *not* for `'static`? If this ever becomes a problem
-        // we'll need to leave some sort of trace of this requirement in the MIR so that borrowck
-        // can ensure that the type really implements `PartialEq`.
-        infcx.predicate_must_hold_modulo_regions(&partial_eq_obligation)
-    }
-
     fn field_pats(
         &self,
         vals: impl Iterator<Item = (ValTree<'tcx>, Ty<'tcx>)>,
@@ -190,10 +219,25 @@ impl<'tcx> ConstToPat<'tcx> {
                 // Extremely important check for all ADTs! Make sure they opted-in to be used in
                 // patterns.
                 debug!("adt_def {:?} has !type_marked_structural for cv.ty: {:?}", adt_def, ty);
-                let err = TypeNotStructural { span, non_sm_ty: ty };
-                let e = tcx.dcx().emit_err(err);
-                // We errored. Signal that in the pattern, so that follow up errors can be silenced.
-                PatKind::Error(e)
+                let (_impls_partial_eq, derived, structural, impl_def_id) =
+                    type_has_partial_eq_impl(self.tcx, self.typing_env, ty);
+                let (manual_partialeq_impl_span, manual_partialeq_impl_note) =
+                    match (structural, impl_def_id) {
+                        (true, _) => (None, false),
+                        (_, Some(def_id)) if def_id.is_local() && !derived => {
+                            (Some(tcx.def_span(def_id)), false)
+                        }
+                        _ => (None, true),
+                    };
+                let ty_def_span = tcx.def_span(adt_def.did());
+                let err = TypeNotStructural {
+                    span,
+                    ty,
+                    ty_def_span,
+                    manual_partialeq_impl_span,
+                    manual_partialeq_impl_note,
+                };
+                return self.mk_err(tcx.dcx().create_err(err), ty);
             }
             ty::Adt(adt_def, args) if adt_def.is_enum() => {
                 let (&variant_index, fields) = cv.unwrap_branch().split_first().unwrap();
@@ -207,7 +251,7 @@ impl<'tcx> ConstToPat<'tcx> {
                             adt_def.variants()[variant_index]
                                 .fields
                                 .iter()
-                                .map(|field| field.ty(self.tcx, args)),
+                                .map(|field| field.ty(tcx, args)),
                         ),
                     ),
                 }
@@ -216,7 +260,7 @@ impl<'tcx> ConstToPat<'tcx> {
                 assert!(!def.is_union()); // Valtree construction would never succeed for unions.
                 PatKind::Leaf {
                     subpatterns: self.field_pats(cv.unwrap_branch().iter().copied().zip(
-                        def.non_enum_variant().fields.iter().map(|field| field.ty(self.tcx, args)),
+                        def.non_enum_variant().fields.iter().map(|field| field.ty(tcx, args)),
                     )),
                 }
             }
@@ -252,10 +296,10 @@ impl<'tcx> ConstToPat<'tcx> {
                 // deref pattern.
                 _ => {
                     if !pointee_ty.is_sized(tcx, self.typing_env) && !pointee_ty.is_slice() {
-                        let err = UnsizedPattern { span, non_sm_ty: *pointee_ty };
-                        let e = tcx.dcx().emit_err(err);
-                        // We errored. Signal that in the pattern, so that follow up errors can be silenced.
-                        PatKind::Error(e)
+                        return self.mk_err(
+                            tcx.dcx().create_err(UnsizedPattern { span, non_sm_ty: *pointee_ty }),
+                            ty,
+                        );
                     } else {
                         // `b"foo"` produces a `&[u8; 3]`, but you can't use constants of array type when
                         // matching against references, you can only use byte string literals.
@@ -286,8 +330,7 @@ impl<'tcx> ConstToPat<'tcx> {
                 if is_nan {
                     // NaNs are not ever equal to anything so they make no sense as patterns.
                     // Also see <https://github.com/rust-lang/rfcs/pull/3535>.
-                    let e = tcx.dcx().emit_err(NaNPattern { span });
-                    PatKind::Error(e)
+                    return self.mk_err(tcx.dcx().create_err(NaNPattern { span }), ty);
                 } else {
                     PatKind::Constant {
                         value: mir::Const::Ty(ty, ty::Const::new_value(tcx, cv, ty)),
@@ -305,13 +348,153 @@ impl<'tcx> ConstToPat<'tcx> {
                 )
             }
             _ => {
-                let err = InvalidPattern { span, non_sm_ty: ty };
-                let e = tcx.dcx().emit_err(err);
-                // We errored. Signal that in the pattern, so that follow up errors can be silenced.
-                PatKind::Error(e)
+                let err = InvalidPattern {
+                    span,
+                    non_sm_ty: ty,
+                    prefix: ty.prefix_string(tcx).to_string(),
+                };
+                return self.mk_err(tcx.dcx().create_err(err), ty);
             }
         };
 
         Box::new(Pat { span, ty, kind })
     }
 }
+
+/// Given a type with type parameters, visit every ADT looking for types that need to
+/// `#[derive(PartialEq)]` for it to be a structural type.
+fn extend_type_not_partial_eq<'tcx>(
+    tcx: TyCtxt<'tcx>,
+    typing_env: ty::TypingEnv<'tcx>,
+    ty: Ty<'tcx>,
+    err: &mut Diag<'_>,
+) {
+    /// Collect all types that need to be `StructuralPartialEq`.
+    struct UsedParamsNeedInstantiationVisitor<'tcx> {
+        tcx: TyCtxt<'tcx>,
+        typing_env: ty::TypingEnv<'tcx>,
+        /// The user has written `impl PartialEq for Ty` which means it's non-structual.
+        adts_with_manual_partialeq: FxHashSet<Span>,
+        /// The type has no `PartialEq` implementation, neither manual or derived.
+        adts_without_partialeq: FxHashSet<Span>,
+        /// The user has written `impl PartialEq for Ty` which means it's non-structual,
+        /// but we don't have a span to point at, so we'll just add them as a `note`.
+        manual: Vec<Ty<'tcx>>,
+        /// The type has no `PartialEq` implementation, neither manual or derived, but
+        /// we don't have a span to point at, so we'll just add them as a `note`.
+        without: Vec<Ty<'tcx>>,
+    }
+
+    impl<'tcx> TypeVisitor<TyCtxt<'tcx>> for UsedParamsNeedInstantiationVisitor<'tcx> {
+        fn visit_ty(&mut self, ty: Ty<'tcx>) -> Self::Result {
+            if let ty::Adt(def, _args) = ty.kind() {
+                let ty_def_id = def.did();
+                let ty_def_span = self.tcx.def_span(ty_def_id);
+                let (impls_partial_eq, derived, structural, impl_def_id) =
+                    type_has_partial_eq_impl(self.tcx, self.typing_env, ty);
+                match (impls_partial_eq, derived, structural, impl_def_id) {
+                    (_, _, true, _) => {}
+                    (true, false, _, Some(def_id)) if def_id.is_local() => {
+                        self.adts_with_manual_partialeq.insert(self.tcx.def_span(def_id));
+                    }
+                    (true, false, _, _) if ty_def_id.is_local() => {
+                        self.adts_with_manual_partialeq.insert(ty_def_span);
+                    }
+                    (false, _, _, _) if ty_def_id.is_local() => {
+                        self.adts_without_partialeq.insert(ty_def_span);
+                    }
+                    (true, false, _, _) => {
+                        self.manual.push(ty);
+                    }
+                    (false, _, _, _) => {
+                        self.without.push(ty);
+                    }
+                    _ => {}
+                };
+            }
+            use rustc_middle::ty::TypeSuperVisitable;
+            ty.super_visit_with(self)
+        }
+    }
+    let mut v = UsedParamsNeedInstantiationVisitor {
+        tcx,
+        typing_env,
+        adts_with_manual_partialeq: FxHashSet::default(),
+        adts_without_partialeq: FxHashSet::default(),
+        manual: vec![],
+        without: vec![],
+    };
+    v.visit_ty(ty);
+    #[allow(rustc::potential_query_instability)] // Span labels will be sorted by the rendering
+    for span in v.adts_with_manual_partialeq {
+        err.span_note(span, "the `PartialEq` trait must be derived, manual `impl`s are not sufficient; see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details");
+    }
+    #[allow(rustc::potential_query_instability)] // Span labels will be sorted by the rendering
+    for span in v.adts_without_partialeq {
+        err.span_label(
+            span,
+            "must be annotated with `#[derive(PartialEq)]` to be usable in patterns",
+        );
+    }
+    for ty in v.manual {
+        err.note(format!(
+            "`{ty}` must be annotated with `#[derive(PartialEq)]` to be usable in patterns, manual `impl`s are not sufficient; see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details"
+        ));
+    }
+    for ty in v.without {
+        err.note(format!(
+            "`{ty}` must be annotated with `#[derive(PartialEq)]` to be usable in patterns"
+        ));
+    }
+}
+
+#[instrument(level = "trace", skip(tcx), ret)]
+fn type_has_partial_eq_impl<'tcx>(
+    tcx: TyCtxt<'tcx>,
+    typing_env: ty::TypingEnv<'tcx>,
+    ty: Ty<'tcx>,
+) -> (
+    /* has impl */ bool,
+    /* is derived */ bool,
+    /* structural partial eq */ bool,
+    /* non-blanket impl */ Option<DefId>,
+) {
+    let (infcx, param_env) = tcx.infer_ctxt().build_with_typing_env(typing_env);
+    // double-check there even *is* a semantic `PartialEq` to dispatch to.
+    //
+    // (If there isn't, then we can safely issue a hard
+    // error, because that's never worked, due to compiler
+    // using `PartialEq::eq` in this scenario in the past.)
+    let partial_eq_trait_id = tcx.require_lang_item(hir::LangItem::PartialEq, None);
+    let structural_partial_eq_trait_id = tcx.require_lang_item(hir::LangItem::StructuralPeq, None);
+
+    let partial_eq_obligation = Obligation::new(
+        tcx,
+        ObligationCause::dummy(),
+        param_env,
+        ty::TraitRef::new(tcx, partial_eq_trait_id, [ty, ty]),
+    );
+
+    let mut automatically_derived = false;
+    let mut structural_peq = false;
+    let mut impl_def_id = None;
+    for def_id in tcx.non_blanket_impls_for_ty(partial_eq_trait_id, ty) {
+        automatically_derived = tcx.has_attr(def_id, sym::automatically_derived);
+        impl_def_id = Some(def_id);
+    }
+    for _ in tcx.non_blanket_impls_for_ty(structural_partial_eq_trait_id, ty) {
+        structural_peq = true;
+    }
+    // This *could* accept a type that isn't actually `PartialEq`, because region bounds get
+    // ignored. However that should be pretty much impossible since consts that do not depend on
+    // generics can only mention the `'static` lifetime, and how would one have a type that's
+    // `PartialEq` for some lifetime but *not* for `'static`? If this ever becomes a problem
+    // we'll need to leave some sort of trace of this requirement in the MIR so that borrowck
+    // can ensure that the type really implements `PartialEq`.
+    (
+        infcx.predicate_must_hold_modulo_regions(&partial_eq_obligation),
+        automatically_derived,
+        structural_peq,
+        impl_def_id,
+    )
+}

compiler/rustc_mir_build/src/thir/pattern/mod.rs

@@ -528,11 +528,17 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> {
             | Res::SelfCtor(..) => PatKind::Leaf { subpatterns },
             _ => {
                 let e = match res {
-                    Res::Def(DefKind::ConstParam, _) => {
-                        self.tcx.dcx().emit_err(ConstParamInPattern { span })
+                    Res::Def(DefKind::ConstParam, def_id) => {
+                        self.tcx.dcx().emit_err(ConstParamInPattern {
+                            span,
+                            const_span: self.tcx().def_span(def_id),
+                        })
                     }
-                    Res::Def(DefKind::Static { .. }, _) => {
-                        self.tcx.dcx().emit_err(StaticInPattern { span })
+                    Res::Def(DefKind::Static { .. }, def_id) => {
+                        self.tcx.dcx().emit_err(StaticInPattern {
+                            span,
+                            static_span: self.tcx().def_span(def_id),
+                        })
                     }
                     _ => self.tcx.dcx().emit_err(NonConstPath { span }),
                 };

compiler/rustc_mir_transform/src/shim.rs

@@ -747,8 +747,8 @@ fn build_call_shim<'tcx>(
         sig.inputs_and_output = tcx.mk_type_list(&inputs_and_output);
     }
 
-    // FIXME(eddyb) avoid having this snippet both here and in
-    // `Instance::fn_sig` (introduce `InstanceKind::fn_sig`?).
+    // FIXME: Avoid having to adjust the signature both here and in
+    // `fn_sig_for_fn_abi`.
     if let ty::InstanceKind::VTableShim(..) = instance {
         // Modify fn(self, ...) to fn(self: *mut Self, ...)
         let mut inputs_and_output = sig.inputs_and_output.to_vec();

compiler/rustc_parse/messages.ftl

@@ -343,6 +343,9 @@ parse_incorrect_semicolon =
     .suggestion = remove this semicolon
     .help = {$name} declarations are not followed by a semicolon
 
+parse_incorrect_type_on_self = type not allowed for shorthand `self` parameter
+    .suggestion = move the modifiers on `self` to the type
+
 parse_incorrect_use_of_await = incorrect use of `await`
     .parentheses_suggestion = `await` is not a method call, remove the parentheses
 

compiler/rustc_parse/src/errors.rs

@@ -3409,3 +3409,22 @@ pub(crate) struct PolarityAndModifiers {
     pub polarity: &'static str,
     pub modifiers_concatenated: String,
 }
+
+#[derive(Diagnostic)]
+#[diag(parse_incorrect_type_on_self)]
+pub(crate) struct IncorrectTypeOnSelf {
+    #[primary_span]
+    pub span: Span,
+    #[subdiagnostic]
+    pub move_self_modifier: MoveSelfModifier,
+}
+
+#[derive(Subdiagnostic)]
+#[multipart_suggestion(parse_suggestion, applicability = "machine-applicable")]
+pub(crate) struct MoveSelfModifier {
+    #[suggestion_part(code = "")]
+    pub removal_span: Span,
+    #[suggestion_part(code = "{modifier}")]
+    pub insertion_span: Span,
+    pub modifier: String,
+}

compiler/rustc_parse/src/parser/item.rs

@@ -2941,6 +2941,32 @@ impl<'a> Parser<'a> {
             };
             Ok((eself, eself_ident, eself_hi))
         };
+        let expect_self_ident_not_typed =
+            |this: &mut Self, modifier: &SelfKind, modifier_span: Span| {
+                let eself_ident = expect_self_ident(this);
+
+                // Recover `: Type` after a qualified self
+                if this.may_recover() && this.eat_noexpect(&token::Colon) {
+                    let snap = this.create_snapshot_for_diagnostic();
+                    match this.parse_ty() {
+                        Ok(ty) => {
+                            this.dcx().emit_err(errors::IncorrectTypeOnSelf {
+                                span: ty.span,
+                                move_self_modifier: errors::MoveSelfModifier {
+                                    removal_span: modifier_span,
+                                    insertion_span: ty.span.shrink_to_lo(),
+                                    modifier: modifier.to_ref_suggestion(),
+                                },
+                            });
+                        }
+                        Err(diag) => {
+                            diag.cancel();
+                            this.restore_snapshot(snap);
+                        }
+                    }
+                }
+                eself_ident
+            };
         // Recover for the grammar `*self`, `*const self`, and `*mut self`.
         let recover_self_ptr = |this: &mut Self| {
             this.dcx().emit_err(errors::SelfArgumentPointer { span: this.token.span });
@@ -2978,7 +3004,9 @@ impl<'a> Parser<'a> {
                     // `&not_self`
                     return Ok(None);
                 };
-                (eself, expect_self_ident(self), self.prev_token.span)
+                let hi = self.token.span;
+                let self_ident = expect_self_ident_not_typed(self, &eself, eself_lo.until(hi));
+                (eself, self_ident, hi)
             }
             // `*self`
             token::BinOp(token::Star) if is_isolated_self(self, 1) => {

compiler/rustc_trait_selection/src/error_reporting/traits/suggestions.rs

@@ -3838,6 +3838,7 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
                 && self.predicate_must_hold_modulo_regions(&Obligation::misc(
                     tcx, expr.span, body_id, param_env, pred,
                 ))
+                && expr.span.hi() != rcvr.span.hi()
             {
                 err.span_suggestion_verbose(
                     expr.span.with_lo(rcvr.span.hi()),
@@ -4115,6 +4116,11 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
                         // the expected is a projection that we need to resolve.
                         // && let Some(tail_ty) = typeck_results.expr_ty_opt(expr)
                         && expected_found.found.is_unit()
+                        // FIXME: this happens with macro calls. Need to figure out why the stmt
+                        // `println!();` doesn't include the `;` in its `Span`. (#133845)
+                        // We filter these out to avoid ICEs with debug assertions on caused by
+                        // empty suggestions.
+                        && expr.span.hi() != stmt.span.hi()
                     {
                         err.span_suggestion_verbose(
                             expr.span.shrink_to_hi().with_hi(stmt.span.hi()),

compiler/rustc_trait_selection/src/traits/select/confirmation.rs

@@ -16,9 +16,7 @@ use rustc_hir::lang_items::LangItem;
 use rustc_infer::infer::{DefineOpaqueTypes, HigherRankedType, InferOk};
 use rustc_infer::traits::ObligationCauseCode;
 use rustc_middle::traits::{BuiltinImplSource, SignatureMismatchData};
-use rustc_middle::ty::{
-    self, GenericArgs, GenericArgsRef, GenericParamDefKind, ToPolyTraitRef, Ty, TyCtxt, Upcast,
-};
+use rustc_middle::ty::{self, GenericArgsRef, ToPolyTraitRef, Ty, TyCtxt, Upcast};
 use rustc_middle::{bug, span_bug};
 use rustc_span::def_id::DefId;
 use tracing::{debug, instrument};
@@ -638,60 +636,12 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
             // higher-ranked things.
             // Prevent, e.g., `dyn Iterator<Item = str>`.
             for bound in self.tcx().item_bounds(assoc_type).transpose_iter() {
-                let arg_bound = if defs.is_empty() {
-                    bound.instantiate(tcx, trait_predicate.trait_ref.args)
-                } else {
-                    let mut args = smallvec::SmallVec::with_capacity(defs.count());
-                    args.extend(trait_predicate.trait_ref.args.iter());
-                    let mut bound_vars: smallvec::SmallVec<[ty::BoundVariableKind; 8]> =
-                        smallvec::SmallVec::with_capacity(
-                            bound.skip_binder().kind().bound_vars().len() + defs.count(),
-                        );
-                    bound_vars.extend(bound.skip_binder().kind().bound_vars().into_iter());
-                    GenericArgs::fill_single(&mut args, defs, &mut |param, _| match param.kind {
-                        GenericParamDefKind::Type { .. } => {
-                            let kind = ty::BoundTyKind::Param(param.def_id, param.name);
-                            let bound_var = ty::BoundVariableKind::Ty(kind);
-                            bound_vars.push(bound_var);
-                            Ty::new_bound(tcx, ty::INNERMOST, ty::BoundTy {
-                                var: ty::BoundVar::from_usize(bound_vars.len() - 1),
-                                kind,
-                            })
-                            .into()
-                        }
-                        GenericParamDefKind::Lifetime => {
-                            let kind = ty::BoundRegionKind::Named(param.def_id, param.name);
-                            let bound_var = ty::BoundVariableKind::Region(kind);
-                            bound_vars.push(bound_var);
-                            ty::Region::new_bound(tcx, ty::INNERMOST, ty::BoundRegion {
-                                var: ty::BoundVar::from_usize(bound_vars.len() - 1),
-                                kind,
-                            })
-                            .into()
-                        }
-                        GenericParamDefKind::Const { .. } => {
-                            let bound_var = ty::BoundVariableKind::Const;
-                            bound_vars.push(bound_var);
-                            ty::Const::new_bound(
-                                tcx,
-                                ty::INNERMOST,
-                                ty::BoundVar::from_usize(bound_vars.len() - 1),
-                            )
-                            .into()
-                        }
-                    });
-                    let bound_vars = tcx.mk_bound_variable_kinds(&bound_vars);
-                    let assoc_ty_args = tcx.mk_args(&args);
-                    let bound =
-                        bound.map_bound(|b| b.kind().skip_binder()).instantiate(tcx, assoc_ty_args);
-                    ty::Binder::bind_with_vars(bound, bound_vars).upcast(tcx)
-                };
                 let normalized_bound = normalize_with_depth_to(
                     self,
                     obligation.param_env,
                     obligation.cause.clone(),
                     obligation.recursion_depth + 1,
-                    arg_bound,
+                    bound.instantiate(tcx, trait_predicate.trait_ref.args),
                     &mut nested,
                 );
                 nested.push(obligation.with(tcx, normalized_bound));

compiler/rustc_ty_utils/src/abi.rs

@@ -31,20 +31,20 @@ fn fn_sig_for_fn_abi<'tcx>(
     tcx: TyCtxt<'tcx>,
     instance: ty::Instance<'tcx>,
     typing_env: ty::TypingEnv<'tcx>,
-) -> ty::PolyFnSig<'tcx> {
+) -> ty::FnSig<'tcx> {
     if let InstanceKind::ThreadLocalShim(..) = instance.def {
-        return ty::Binder::dummy(tcx.mk_fn_sig(
+        return tcx.mk_fn_sig(
             [],
             tcx.thread_local_ptr_ty(instance.def_id()),
             false,
             hir::Safety::Safe,
             rustc_abi::ExternAbi::Unadjusted,
-        ));
+        );
     }
 
     let ty = instance.ty(tcx, typing_env);
     match *ty.kind() {
-        ty::FnDef(..) => {
+        ty::FnDef(def_id, args) => {
             // HACK(davidtwco,eddyb): This is a workaround for polymorphization considering
             // parameters unused if they show up in the signature, but not in the `mir::Body`
             // (i.e. due to being inside a projection that got normalized, see
@@ -52,9 +52,8 @@ fn fn_sig_for_fn_abi<'tcx>(
             // track of a polymorphization `ParamEnv` to allow normalizing later.
             //
             // We normalize the `fn_sig` again after instantiating at a later point.
-            let mut sig = match *ty.kind() {
-                ty::FnDef(def_id, args) => tcx
-                    .fn_sig(def_id)
+            let mut sig = tcx.instantiate_bound_regions_with_erased(
+                tcx.fn_sig(def_id)
                     .map_bound(|fn_sig| {
                         tcx.normalize_erasing_regions(
                             ty::TypingEnv::non_body_analysis(tcx, def_id),
@@ -62,62 +61,36 @@ fn fn_sig_for_fn_abi<'tcx>(
                         )
                     })
                     .instantiate(tcx, args),
-                _ => unreachable!(),
-            };
+            );
 
             if let ty::InstanceKind::VTableShim(..) = instance.def {
-                // Modify `fn(self, ...)` to `fn(self: *mut Self, ...)`.
-                sig = sig.map_bound(|mut sig| {
                 let mut inputs_and_output = sig.inputs_and_output.to_vec();
                 inputs_and_output[0] = Ty::new_mut_ptr(tcx, inputs_and_output[0]);
                 sig.inputs_and_output = tcx.mk_type_list(&inputs_and_output);
-                    sig
-                });
             }
+
             sig
         }
         ty::Closure(def_id, args) => {
-            let sig = args.as_closure().sig();
-
-            let bound_vars =
-                tcx.mk_bound_variable_kinds_from_iter(sig.bound_vars().iter().chain(iter::once(
-                    ty::BoundVariableKind::Region(ty::BoundRegionKind::ClosureEnv),
-                )));
-            let br = ty::BoundRegion {
-                var: ty::BoundVar::from_usize(bound_vars.len() - 1),
-                kind: ty::BoundRegionKind::ClosureEnv,
-            };
-            let env_region = ty::Region::new_bound(tcx, ty::INNERMOST, br);
+            let sig = tcx.instantiate_bound_regions_with_erased(args.as_closure().sig());
             let env_ty = tcx.closure_env_ty(
                 Ty::new_closure(tcx, def_id, args),
                 args.as_closure().kind(),
-                env_region,
+                tcx.lifetimes.re_erased,
             );
 
-            let sig = sig.skip_binder();
-            ty::Binder::bind_with_vars(
             tcx.mk_fn_sig(
                 iter::once(env_ty).chain(sig.inputs().iter().cloned()),
                 sig.output(),
                 sig.c_variadic,
                 sig.safety,
                 sig.abi,
-                ),
-                bound_vars,
             )
         }
         ty::CoroutineClosure(def_id, args) => {
             let coroutine_ty = Ty::new_coroutine_closure(tcx, def_id, args);
             let sig = args.as_coroutine_closure().coroutine_closure_sig();
-            let bound_vars =
-                tcx.mk_bound_variable_kinds_from_iter(sig.bound_vars().iter().chain(iter::once(
-                    ty::BoundVariableKind::Region(ty::BoundRegionKind::ClosureEnv),
-                )));
-            let br = ty::BoundRegion {
-                var: ty::BoundVar::from_usize(bound_vars.len() - 1),
-                kind: ty::BoundRegionKind::ClosureEnv,
-            };
-            let env_region = ty::Region::new_bound(tcx, ty::INNERMOST, br);
+
             // When this `CoroutineClosure` comes from a `ConstructCoroutineInClosureShim`,
             // make sure we respect the `target_kind` in that shim.
             // FIXME(async_closures): This shouldn't be needed, and we should be populating
@@ -138,11 +111,11 @@ fn fn_sig_for_fn_abi<'tcx>(
                         coroutine_ty
                     }
                 } else {
-                    tcx.closure_env_ty(coroutine_ty, coroutine_kind, env_region)
+                    tcx.closure_env_ty(coroutine_ty, coroutine_kind, tcx.lifetimes.re_erased)
                 };
 
-            let sig = sig.skip_binder();
-            ty::Binder::bind_with_vars(
+            let sig = tcx.instantiate_bound_regions_with_erased(sig);
+
             tcx.mk_fn_sig(
                 iter::once(env_ty).chain([sig.tupled_inputs_ty]),
                 sig.to_coroutine_given_kind_and_upvars(
@@ -150,30 +123,20 @@ fn fn_sig_for_fn_abi<'tcx>(
                     args.as_coroutine_closure().parent_args(),
                     tcx.coroutine_for_closure(def_id),
                     coroutine_kind,
-                        env_region,
+                    tcx.lifetimes.re_erased,
                     args.as_coroutine_closure().tupled_upvars_ty(),
                     args.as_coroutine_closure().coroutine_captures_by_ref_ty(),
                 ),
                 sig.c_variadic,
                 sig.safety,
                 sig.abi,
-                ),
-                bound_vars,
             )
         }
         ty::Coroutine(did, args) => {
             let coroutine_kind = tcx.coroutine_kind(did).unwrap();
             let sig = args.as_coroutine().sig();
 
-            let bound_vars = tcx.mk_bound_variable_kinds_from_iter(iter::once(
-                ty::BoundVariableKind::Region(ty::BoundRegionKind::ClosureEnv),
-            ));
-            let br = ty::BoundRegion {
-                var: ty::BoundVar::from_usize(bound_vars.len() - 1),
-                kind: ty::BoundRegionKind::ClosureEnv,
-            };
-
-            let env_ty = Ty::new_mut_ref(tcx, ty::Region::new_bound(tcx, ty::INNERMOST, br), ty);
+            let env_ty = Ty::new_mut_ref(tcx, tcx.lifetimes.re_erased, ty);
 
             let pin_did = tcx.require_lang_item(LangItem::Pin, None);
             let pin_adt_ref = tcx.adt_def(pin_did);
@@ -268,7 +231,7 @@ fn fn_sig_for_fn_abi<'tcx>(
                 }
             };
 
-            let fn_sig = if let Some(resume_ty) = resume_ty {
+            if let Some(resume_ty) = resume_ty {
                 tcx.mk_fn_sig(
                     [env_ty, resume_ty],
                     ret_ty,
@@ -285,8 +248,7 @@ fn fn_sig_for_fn_abi<'tcx>(
                     hir::Safety::Safe,
                     rustc_abi::ExternAbi::Rust,
                 )
-            };
-            ty::Binder::bind_with_vars(fn_sig, bound_vars)
+            }
         }
         _ => bug!("unexpected type {:?} in Instance::fn_sig", ty),
     }
@@ -335,8 +297,16 @@ fn fn_abi_of_fn_ptr<'tcx>(
     query: ty::PseudoCanonicalInput<'tcx, (ty::PolyFnSig<'tcx>, &'tcx ty::List<Ty<'tcx>>)>,
 ) -> Result<&'tcx FnAbi<'tcx, Ty<'tcx>>, &'tcx FnAbiError<'tcx>> {
     let ty::PseudoCanonicalInput { typing_env, value: (sig, extra_args) } = query;
+
     let cx = LayoutCx::new(tcx, typing_env);
-    fn_abi_new_uncached(&cx, sig, extra_args, None, None, false)
+    fn_abi_new_uncached(
+        &cx,
+        tcx.instantiate_bound_regions_with_erased(sig),
+        extra_args,
+        None,
+        None,
+        false,
+    )
 }
 
 fn fn_abi_of_instance<'tcx>(
@@ -567,7 +537,7 @@ fn fn_abi_sanity_check<'tcx>(
 #[tracing::instrument(level = "debug", skip(cx, caller_location, fn_def_id, force_thin_self_ptr))]
 fn fn_abi_new_uncached<'tcx>(
     cx: &LayoutCx<'tcx>,
-    sig: ty::PolyFnSig<'tcx>,
+    sig: ty::FnSig<'tcx>,
     extra_args: &[Ty<'tcx>],
     caller_location: Option<Ty<'tcx>>,
     fn_def_id: Option<DefId>,
@@ -575,7 +545,7 @@ fn fn_abi_new_uncached<'tcx>(
     force_thin_self_ptr: bool,
 ) -> Result<&'tcx FnAbi<'tcx, Ty<'tcx>>, &'tcx FnAbiError<'tcx>> {
     let tcx = cx.tcx();
-    let sig = tcx.normalize_erasing_late_bound_regions(cx.typing_env, sig);
+    let sig = tcx.normalize_erasing_regions(cx.typing_env, sig);
 
     let conv = conv_from_spec_abi(cx.tcx(), sig.abi, sig.c_variadic);
 

library/core/src/lib.rs

@@ -345,7 +345,7 @@ pub mod net;
 pub mod option;
 pub mod panic;
 pub mod panicking;
-#[unstable(feature = "core_pattern_types", issue = "123646")]
+#[unstable(feature = "pattern_type_macro", issue = "123646")]
 pub mod pat;
 pub mod pin;
 #[unstable(feature = "random", issue = "130703")]

library/core/src/pat.rs

@@ -6,7 +6,7 @@
 /// ```
 #[macro_export]
 #[rustc_builtin_macro(pattern_type)]
-#[unstable(feature = "core_pattern_type", issue = "123646")]
+#[unstable(feature = "pattern_type_macro", issue = "123646")]
 macro_rules! pattern_type {
     ($($arg:tt)*) => {
         /* compiler built-in */

library/core/tests/ptr.rs

@@ -304,6 +304,7 @@ fn test_const_nonnull_new() {
 #[test]
 #[cfg(unix)] // printf may not be available on other platforms
 #[allow(deprecated)] // For SipHasher
+#[cfg_attr(not(bootstrap), allow(unpredictable_function_pointer_comparisons))]
 pub fn test_variadic_fnptr() {
     use core::ffi;
     use core::hash::{Hash, SipHasher};

library/std/src/lib.rs

@@ -589,7 +589,7 @@ pub mod net;
 pub mod num;
 pub mod os;
 pub mod panic;
-#[unstable(feature = "core_pattern_types", issue = "123646")]
+#[unstable(feature = "pattern_type_macro", issue = "123646")]
 pub mod pat;
 pub mod path;
 #[unstable(feature = "anonymous_pipe", issue = "127154")]

src/bootstrap/src/bin/main.rs

@@ -48,9 +48,9 @@ fn main() {
             err => {
                 drop(err);
                 if let Ok(pid) = pid {
-                    eprintln!("WARNING: build directory locked by process {pid}, waiting for lock");
+                    println!("WARNING: build directory locked by process {pid}, waiting for lock");
                 } else {
-                    eprintln!("WARNING: build directory locked, waiting for lock");
+                    println!("WARNING: build directory locked, waiting for lock");
                 }
                 let mut lock = t!(build_lock.write());
                 t!(lock.write(process::id().to_string().as_ref()));
@@ -70,13 +70,13 @@ fn main() {
     // changelog warning, not the `x.py setup` message.
     let suggest_setup = config.config.is_none() && !matches!(config.cmd, Subcommand::Setup { .. });
     if suggest_setup {
-        eprintln!("WARNING: you have not made a `config.toml`");
-        eprintln!(
+        println!("WARNING: you have not made a `config.toml`");
+        println!(
             "HELP: consider running `./x.py setup` or copying `config.example.toml` by running \
             `cp config.example.toml config.toml`"
         );
     } else if let Some(suggestion) = &changelog_suggestion {
-        eprintln!("{suggestion}");
+        println!("{suggestion}");
     }
 
     let pre_commit = config.src.join(".git").join("hooks").join("pre-commit");
@@ -86,13 +86,13 @@ fn main() {
     Build::new(config).build();
 
     if suggest_setup {
-        eprintln!("WARNING: you have not made a `config.toml`");
-        eprintln!(
+        println!("WARNING: you have not made a `config.toml`");
+        println!(
             "HELP: consider running `./x.py setup` or copying `config.example.toml` by running \
             `cp config.example.toml config.toml`"
         );
     } else if let Some(suggestion) = &changelog_suggestion {
-        eprintln!("{suggestion}");
+        println!("{suggestion}");
     }
 
     // Give a warning if the pre-commit script is in pre-commit and not pre-push.
@@ -102,14 +102,14 @@ fn main() {
     if fs::read_to_string(pre_commit).is_ok_and(|contents| {
         contents.contains("https://github.com/rust-lang/rust/issues/77620#issuecomment-705144570")
     }) {
-        eprintln!(
+        println!(
             "WARNING: You have the pre-push script installed to .git/hooks/pre-commit. \
                   Consider moving it to .git/hooks/pre-push instead, which runs less often."
         );
     }
 
     if suggest_setup || changelog_suggestion.is_some() {
-        eprintln!("NOTE: this message was printed twice to make it more likely to be seen");
+        println!("NOTE: this message was printed twice to make it more likely to be seen");
     }
 
     if dump_bootstrap_shims {

src/bootstrap/src/bin/rustc.rs

@@ -306,7 +306,7 @@ fn main() {
         // should run on success, after this block.
     }
     if verbose > 0 {
-        eprintln!("\nDid not run successfully: {status}\n{cmd:?}\n-------------");
+        println!("\nDid not run successfully: {status}\n{cmd:?}\n-------------");
     }
 
     if let Some(mut on_fail) = on_fail {

src/bootstrap/src/core/build_steps/check.rs

@@ -287,7 +287,7 @@ impl Step for CodegenBackend {
     fn run(self, builder: &Builder<'_>) {
         // FIXME: remove once https://github.com/rust-lang/rust/issues/112393 is resolved
         if builder.build.config.vendor && self.backend == "gcc" {
-            eprintln!("Skipping checking of `rustc_codegen_gcc` with vendoring enabled.");
+            println!("Skipping checking of `rustc_codegen_gcc` with vendoring enabled.");
             return;
         }
 

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

@@ -1611,7 +1611,7 @@ impl Step for Sysroot {
         let sysroot = sysroot_dir(compiler.stage);
 
         builder
-            .verbose(|| eprintln!("Removing sysroot {} to avoid caching bugs", sysroot.display()));
+            .verbose(|| println!("Removing sysroot {} to avoid caching bugs", sysroot.display()));
         let _ = fs::remove_dir_all(&sysroot);
         t!(fs::create_dir_all(&sysroot));
 
@@ -1681,7 +1681,7 @@ impl Step for Sysroot {
                     return true;
                 }
                 if !filtered_files.iter().all(|f| f != path.file_name().unwrap()) {
-                    builder.verbose_than(1, || eprintln!("ignoring {}", path.display()));
+                    builder.verbose_than(1, || println!("ignoring {}", path.display()));
                     false
                 } else {
                     true
@@ -2240,7 +2240,7 @@ pub fn stream_cargo(
         cargo.arg(arg);
     }
 
-    builder.verbose(|| eprintln!("running: {cargo:?}"));
+    builder.verbose(|| println!("running: {cargo:?}"));
 
     if builder.config.dry_run() {
         return true;
@@ -2261,12 +2261,12 @@ pub fn stream_cargo(
             Ok(msg) => {
                 if builder.config.json_output {
                     // Forward JSON to stdout.
-                    eprintln!("{line}");
+                    println!("{line}");
                 }
                 cb(msg)
             }
             // If this was informational, just print it out and continue
-            Err(_) => eprintln!("{line}"),
+            Err(_) => println!("{line}"),
         }
     }
 

src/bootstrap/src/core/build_steps/dist.rs

@@ -2080,7 +2080,7 @@ fn maybe_install_llvm(
     {
         let mut cmd = command(llvm_config);
         cmd.arg("--libfiles");
-        builder.verbose(|| eprintln!("running {cmd:?}"));
+        builder.verbose(|| println!("running {cmd:?}"));
         let files = cmd.run_capture_stdout(builder).stdout();
         let build_llvm_out = &builder.llvm_out(builder.config.build);
         let target_llvm_out = &builder.llvm_out(target);

src/bootstrap/src/core/build_steps/format.rs

@@ -107,10 +107,10 @@ fn print_paths(verb: &str, adjective: Option<&str>, paths: &[String]) {
         if let Some(adjective) = adjective { format!("{adjective} ") } else { String::new() };
     if len <= 10 {
         for path in paths {
-            eprintln!("fmt: {verb} {adjective}file {path}");
+            println!("fmt: {verb} {adjective}file {path}");
         }
     } else {
-        eprintln!("fmt: {verb} {len} {adjective}files");
+        println!("fmt: {verb} {len} {adjective}files");
     }
 }
 
@@ -199,7 +199,7 @@ pub fn format(build: &Builder<'_>, check: bool, all: bool, paths: &[PathBuf]) {
                 match get_modified_rs_files(build) {
                     Ok(Some(files)) => {
                         if files.is_empty() {
-                            eprintln!("fmt info: No modified files detected for formatting.");
+                            println!("fmt info: No modified files detected for formatting.");
                             return;
                         }
 

src/bootstrap/src/core/build_steps/setup.rs

@@ -134,7 +134,7 @@ impl Step for Profile {
                     t!(fs::remove_file(path));
                 }
                 _ => {
-                    eprintln!("Exiting.");
+                    println!("Exiting.");
                     crate::exit!(1);
                 }
             }
@@ -184,15 +184,15 @@ pub fn setup(config: &Config, profile: Profile) {
         Profile::Dist => &["dist", "build"],
     };
 
-    eprintln!();
+    println!();
 
-    eprintln!("To get started, try one of the following commands:");
+    println!("To get started, try one of the following commands:");
     for cmd in suggestions {
-        eprintln!("- `x.py {cmd}`");
+        println!("- `x.py {cmd}`");
     }
 
     if profile != Profile::Dist {
-        eprintln!(
+        println!(
             "For more suggestions, see https://rustc-dev-guide.rust-lang.org/building/suggested.html"
         );
     }
@@ -224,7 +224,7 @@ fn setup_config_toml(path: &PathBuf, profile: Profile, config: &Config) {
     t!(fs::write(path, settings));
 
     let include_path = profile.include_path(&config.src);
-    eprintln!("`x.py` will now use the configuration at {}", include_path.display());
+    println!("`x.py` will now use the configuration at {}", include_path.display());
 }
 
 /// Creates a toolchain link for stage1 using `rustup`
@@ -256,7 +256,7 @@ impl Step for Link {
         }
 
         if !rustup_installed(builder) {
-            eprintln!("WARNING: `rustup` is not installed; Skipping `stage1` toolchain linking.");
+            println!("WARNING: `rustup` is not installed; Skipping `stage1` toolchain linking.");
             return;
         }
 
@@ -296,7 +296,7 @@ fn attempt_toolchain_link(builder: &Builder<'_>, stage_path: &str) {
     }
 
     if try_link_toolchain(builder, stage_path) {
-        eprintln!(
+        println!(
             "Added `stage1` rustup toolchain; try `cargo +stage1 build` on a separate rust project to run a newly-built toolchain"
         );
     } else {
@@ -321,14 +321,14 @@ fn toolchain_is_linked(builder: &Builder<'_>) -> bool {
                 return false;
             }
             // The toolchain has already been linked.
-            eprintln!(
+            println!(
                 "`stage1` toolchain already linked; not attempting to link `stage1` toolchain"
             );
         }
         None => {
             // In this case, we don't know if the `stage1` toolchain has been linked;
             // but `rustup` failed, so let's not go any further.
-            eprintln!(
+            println!(
                 "`rustup` failed to list current toolchains; not attempting to link `stage1` toolchain"
             );
         }
@@ -389,9 +389,9 @@ pub fn interactive_path() -> io::Result<Profile> {
         input.parse()
     }
 
-    eprintln!("Welcome to the Rust project! What do you want to do with x.py?");
+    println!("Welcome to the Rust project! What do you want to do with x.py?");
     for ((letter, _), profile) in abbrev_all() {
-        eprintln!("{}) {}: {}", letter, profile, profile.purpose());
+        println!("{}) {}: {}", letter, profile, profile.purpose());
     }
     let template = loop {
         print!(
@@ -488,7 +488,7 @@ fn install_git_hook_maybe(builder: &Builder<'_>, config: &Config) -> io::Result<
         return Ok(());
     }
 
-    eprintln!(
+    println!(
         "\nRust's CI will automatically fail if it doesn't pass `tidy`, the internal tool for ensuring code quality.
 If you'd like, x.py can install a git hook for you that will automatically run `test tidy` before
 pushing your code to ensure your code is up to par. If you decide later that this behavior is
@@ -496,7 +496,7 @@ undesirable, simply delete the `pre-push` file from .git/hooks."
     );
 
     if prompt_user("Would you like to install the git hook?: [y/N]")? != Some(PromptResult::Yes) {
-        eprintln!("Ok, skipping installation!");
+        println!("Ok, skipping installation!");
         return Ok(());
     }
     if !hooks_dir.exists() {
@@ -513,7 +513,7 @@ undesirable, simply delete the `pre-push` file from .git/hooks."
             );
             return Err(e);
         }
-        Ok(_) => eprintln!("Linked `src/etc/pre-push.sh` to `.git/hooks/pre-push`"),
+        Ok(_) => println!("Linked `src/etc/pre-push.sh` to `.git/hooks/pre-push`"),
     };
     Ok(())
 }
@@ -654,7 +654,7 @@ impl Step for Editor {
                 if let Some(editor_kind) = editor_kind {
                     while !t!(create_editor_settings_maybe(config, editor_kind.clone())) {}
                 } else {
-                    eprintln!("Ok, skipping editor setup!");
+                    println!("Ok, skipping editor setup!");
                 }
             }
             Err(e) => eprintln!("Could not determine the editor: {e}"),
@@ -687,7 +687,7 @@ fn create_editor_settings_maybe(config: &Config, editor: EditorKind) -> io::Resu
             mismatched_settings = Some(false);
         }
     }
-    eprintln!(
+    println!(
         "\nx.py can automatically install the recommended `{settings_filename}` file for rustc development"
     );
 
@@ -706,7 +706,7 @@ fn create_editor_settings_maybe(config: &Config, editor: EditorKind) -> io::Resu
         Some(PromptResult::Yes) => true,
         Some(PromptResult::Print) => false,
         _ => {
-            eprintln!("Ok, skipping settings!");
+            println!("Ok, skipping settings!");
             return Ok(true);
         }
     };
@@ -733,9 +733,9 @@ fn create_editor_settings_maybe(config: &Config, editor: EditorKind) -> io::Resu
             _ => "Created",
         };
         fs::write(&settings_path, editor.settings_template())?;
-        eprintln!("{verb} `{}`", settings_filename);
+        println!("{verb} `{}`", settings_filename);
     } else {
-        eprintln!("\n{}", editor.settings_template());
+        println!("\n{}", editor.settings_template());
     }
     Ok(should_create)
 }

src/bootstrap/src/core/build_steps/suggest.rs

@@ -66,6 +66,6 @@ pub fn suggest(builder: &Builder<'_>, run: bool) {
             build.build();
         }
     } else {
-        eprintln!("HELP: consider using the `--run` flag to automatically run suggested tests");
+        println!("HELP: consider using the `--run` flag to automatically run suggested tests");
     }
 }

src/bootstrap/src/core/build_steps/test.rs

@@ -471,11 +471,11 @@ impl Miri {
         // We re-use the `cargo` from above.
         cargo.arg("--print-sysroot");
 
-        builder.verbose(|| eprintln!("running: {cargo:?}"));
+        builder.verbose(|| println!("running: {cargo:?}"));
         let stdout = cargo.run_capture_stdout(builder).stdout();
         // Output is "<sysroot>\n".
         let sysroot = stdout.trim_end();
-        builder.verbose(|| eprintln!("`cargo miri setup --print-sysroot` said: {sysroot:?}"));
+        builder.verbose(|| println!("`cargo miri setup --print-sysroot` said: {sysroot:?}"));
         PathBuf::from(sysroot)
     }
 }
@@ -2478,7 +2478,7 @@ fn markdown_test(builder: &Builder<'_>, compiler: Compiler, markdown: &Path) ->
         }
     }
 
-    builder.verbose(|| eprintln!("doc tests for: {}", markdown.display()));
+    builder.verbose(|| println!("doc tests for: {}", markdown.display()));
     let mut cmd = builder.rustdoc_cmd(compiler);
     builder.add_rust_test_threads(&mut cmd);
     // allow for unstable options such as new editions

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

@@ -523,7 +523,7 @@ impl Builder<'_> {
 
         let sysroot_str = sysroot.as_os_str().to_str().expect("sysroot should be UTF-8");
         if self.is_verbose() && !matches!(self.config.dry_run, DryRun::SelfCheck) {
-            eprintln!("using sysroot {sysroot_str}");
+            println!("using sysroot {sysroot_str}");
         }
 
         let mut rustflags = Rustflags::new(target);

src/bootstrap/src/core/builder/mod.rs

@@ -392,14 +392,14 @@ impl StepDescription {
     fn is_excluded(&self, builder: &Builder<'_>, pathset: &PathSet) -> bool {
         if builder.config.skip.iter().any(|e| pathset.has(e, builder.kind)) {
             if !matches!(builder.config.dry_run, DryRun::SelfCheck) {
-                eprintln!("Skipping {pathset:?} because it is excluded");
+                println!("Skipping {pathset:?} because it is excluded");
             }
             return true;
         }
 
         if !builder.config.skip.is_empty() && !matches!(builder.config.dry_run, DryRun::SelfCheck) {
             builder.verbose(|| {
-                eprintln!(
+                println!(
                     "{:?} not skipped for {:?} -- not in {:?}",
                     pathset, self.name, builder.config.skip
                 )
@@ -1437,11 +1437,11 @@ impl<'a> Builder<'a> {
                 panic!("{}", out);
             }
             if let Some(out) = self.cache.get(&step) {
-                self.verbose_than(1, || eprintln!("{}c {:?}", "  ".repeat(stack.len()), step));
+                self.verbose_than(1, || println!("{}c {:?}", "  ".repeat(stack.len()), step));
 
                 return out;
             }
-            self.verbose_than(1, || eprintln!("{}> {:?}", "  ".repeat(stack.len()), step));
+            self.verbose_than(1, || println!("{}> {:?}", "  ".repeat(stack.len()), step));
             stack.push(Box::new(step.clone()));
         }
 
@@ -1462,7 +1462,7 @@ impl<'a> Builder<'a> {
             let step_string = format!("{step:?}");
             let brace_index = step_string.find('{').unwrap_or(0);
             let type_string = type_name::<S>();
-            eprintln!(
+            println!(
                 "[TIMING] {} {} -- {}.{:03}",
                 &type_string.strip_prefix("bootstrap::").unwrap_or(type_string),
                 &step_string[brace_index..],
@@ -1479,9 +1479,7 @@ impl<'a> Builder<'a> {
             let cur_step = stack.pop().expect("step stack empty");
             assert_eq!(cur_step.downcast_ref(), Some(&step));
         }
-        self.verbose_than(1, || {
-            eprintln!("{}< {:?}", "  ".repeat(self.stack.borrow().len()), step)
-        });
+        self.verbose_than(1, || println!("{}< {:?}", "  ".repeat(self.stack.borrow().len()), step));
         self.cache.put(step, out.clone());
         out
     }

src/bootstrap/src/core/config/config.rs

@@ -1293,7 +1293,7 @@ impl Config {
                     .map(|change_id| change_id.inner.map(crate::find_recent_config_change_ids))
                 {
                     if !changes.is_empty() {
-                        eprintln!(
+                        println!(
                             "WARNING: There have been changes to x.py since you last updated:\n{}",
                             crate::human_readable_changes(&changes)
                         );
@@ -1559,7 +1559,7 @@ impl Config {
         }
 
         if cargo_clippy.is_some() && rustc.is_none() {
-            eprintln!(
+            println!(
                 "WARNING: Using `build.cargo-clippy` without `build.rustc` usually fails due to toolchain conflict."
             );
         }
@@ -1841,7 +1841,7 @@ impl Config {
 
             // FIXME: Remove this option at the end of 2024.
             if parallel_compiler.is_some() {
-                eprintln!(
+                println!(
                     "WARNING: The `rust.parallel-compiler` option is deprecated and does nothing. The parallel compiler (with one thread) is now the default"
                 );
             }
@@ -1873,7 +1873,7 @@ impl Config {
                         if available_backends.contains(&backend) {
                             panic!("Invalid value '{s}' for 'rust.codegen-backends'. Instead, please use '{backend}'.");
                         } else {
-                            eprintln!("HELP: '{s}' for 'rust.codegen-backends' might fail. \
+                            println!("HELP: '{s}' for 'rust.codegen-backends' might fail. \
                                 Codegen backends are mostly defined without the '{CODEGEN_BACKEND_PREFIX}' prefix. \
                                 In this case, it would be referred to as '{backend}'.");
                         }
@@ -1902,7 +1902,7 @@ impl Config {
         // tests may fail due to using a different channel than the one used by the compiler during tests.
         if let Some(commit) = &config.download_rustc_commit {
             if is_user_configured_rust_channel {
-                eprintln!(
+                println!(
                     "WARNING: `rust.download-rustc` is enabled. The `rust.channel` option will be overridden by the CI rustc's channel."
                 );
 
@@ -1992,10 +1992,10 @@ impl Config {
 
             if config.llvm_from_ci {
                 let warn = |option: &str| {
-                    eprintln!(
+                    println!(
                         "WARNING: `{option}` will only be used on `compiler/rustc_llvm` build, not for the LLVM build."
                     );
-                    eprintln!(
+                    println!(
                         "HELP: To use `{option}` for LLVM builds, set `download-ci-llvm` option to false."
                     );
                 };
@@ -2014,12 +2014,12 @@ impl Config {
                 // if they've chosen a different value.
 
                 if libzstd.is_some() {
-                    eprintln!(
+                    println!(
                         "WARNING: when using `download-ci-llvm`, the local `llvm.libzstd` option, \
                         like almost all `llvm.*` options, will be ignored and set by the LLVM CI \
                         artifacts builder config."
                     );
-                    eprintln!(
+                    println!(
                         "HELP: To use `llvm.libzstd` for LLVM/LLD builds, set `download-ci-llvm` option to false."
                     );
                 }
@@ -2088,7 +2088,7 @@ impl Config {
                             if available_backends.contains(&backend) {
                                 panic!("Invalid value '{s}' for 'target.{triple}.codegen-backends'. Instead, please use '{backend}'.");
                             } else {
-                                eprintln!("HELP: '{s}' for 'target.{triple}.codegen-backends' might fail. \
+                                println!("HELP: '{s}' for 'target.{triple}.codegen-backends' might fail. \
                                     Codegen backends are mostly defined without the '{CODEGEN_BACKEND_PREFIX}' prefix. \
                                     In this case, it would be referred to as '{backend}'.");
                             }
@@ -2304,7 +2304,7 @@ impl Config {
         if self.dry_run() {
             return Ok(());
         }
-        self.verbose(|| eprintln!("running: {cmd:?}"));
+        self.verbose(|| println!("running: {cmd:?}"));
         build_helper::util::try_run(cmd, self.is_verbose())
     }
 
@@ -2479,7 +2479,7 @@ impl Config {
                         // This happens when LLVM submodule is updated in CI, we should disable ci-rustc without an error
                         // to not break CI. For non-CI environments, we should return an error.
                         if CiEnv::is_ci() {
-                            eprintln!("WARNING: LLVM submodule has changes, `download-rustc` will be disabled.");
+                            println!("WARNING: LLVM submodule has changes, `download-rustc` will be disabled.");
                             return None;
                         } else {
                             panic!("ERROR: LLVM submodule has changes, `download-rustc` can't be used.");
@@ -2490,8 +2490,8 @@ impl Config {
                         let ci_config_toml = match self.get_builder_toml("ci-rustc") {
                             Ok(ci_config_toml) => ci_config_toml,
                             Err(e) if e.to_string().contains("unknown field") => {
-                                eprintln!("WARNING: CI rustc has some fields that are no longer supported in bootstrap; download-rustc will be disabled.");
-                                eprintln!("HELP: Consider rebasing to a newer commit if available.");
+                                println!("WARNING: CI rustc has some fields that are no longer supported in bootstrap; download-rustc will be disabled.");
+                                println!("HELP: Consider rebasing to a newer commit if available.");
                                 return None;
                             },
                             Err(e) => {
@@ -2516,7 +2516,7 @@ impl Config {
                             .is_some_and(|s| s == "1" || s == "true");
 
                         if disable_ci_rustc_if_incompatible && res.is_err() {
-                            eprintln!("WARNING: download-rustc is disabled with `DISABLE_CI_RUSTC_IF_INCOMPATIBLE` env.");
+                            println!("WARNING: download-rustc is disabled with `DISABLE_CI_RUSTC_IF_INCOMPATIBLE` env.");
                             return None;
                         }
 
@@ -2701,7 +2701,7 @@ impl Config {
             return;
         }
 
-        eprintln!("Updating submodule {relative_path}");
+        println!("Updating submodule {relative_path}");
         self.check_run(
             helpers::git(Some(&self.src))
                 .run_always()
@@ -2824,7 +2824,7 @@ impl Config {
             Some(StringOrBool::Bool(true)) => false,
             Some(StringOrBool::String(s)) if s == "if-unchanged" => {
                 if !self.rust_info.is_managed_git_subrepository() {
-                    eprintln!(
+                    println!(
                         "ERROR: `download-rustc=if-unchanged` is only compatible with Git managed sources."
                     );
                     crate::exit!(1);
@@ -2857,10 +2857,10 @@ impl Config {
                 if if_unchanged {
                     return None;
                 }
-                eprintln!("ERROR: could not find commit hash for downloading rustc");
-                eprintln!("HELP: maybe your repository history is too shallow?");
-                eprintln!("HELP: consider setting `rust.download-rustc=false` in config.toml");
-                eprintln!("HELP: or fetch enough history to include one upstream commit");
+                println!("ERROR: could not find commit hash for downloading rustc");
+                println!("HELP: maybe your repository history is too shallow?");
+                println!("HELP: consider setting `rust.download-rustc=false` in config.toml");
+                println!("HELP: or fetch enough history to include one upstream commit");
                 crate::exit!(1);
             }
         };
@@ -2899,7 +2899,7 @@ impl Config {
         let if_unchanged = || {
             if self.rust_info.is_from_tarball() {
                 // Git is needed for running "if-unchanged" logic.
-                eprintln!(
+                println!(
                     "WARNING: 'if-unchanged' has no effect on tarball sources; ignoring `download-ci-llvm`."
                 );
                 return false;
@@ -2948,10 +2948,10 @@ impl Config {
         // Only commits merged by bors will have CI artifacts.
         let commit = get_closest_merge_commit(Some(&self.src), &self.git_config(), &[]).unwrap();
         if commit.is_empty() {
-            eprintln!("error: could not find commit hash for downloading components from CI");
-            eprintln!("help: maybe your repository history is too shallow?");
-            eprintln!("help: consider disabling `{option_name}`");
-            eprintln!("help: or fetch enough history to include one upstream commit");
+            println!("error: could not find commit hash for downloading components from CI");
+            println!("help: maybe your repository history is too shallow?");
+            println!("help: consider disabling `{option_name}`");
+            println!("help: or fetch enough history to include one upstream commit");
             crate::exit!(1);
         }
 
@@ -2963,14 +2963,14 @@ impl Config {
         if has_changes {
             if if_unchanged {
                 if self.is_verbose() {
-                    eprintln!(
+                    println!(
                         "warning: saw changes to one of {modified_paths:?} since {commit}; \
                             ignoring `{option_name}`"
                     );
                 }
                 return None;
             }
-            eprintln!(
+            println!(
                 "warning: `{option_name}` is enabled, but there are changes to one of {modified_paths:?}"
             );
         }
@@ -3007,7 +3007,7 @@ pub(crate) fn check_incompatible_options_for_ci_llvm(
         ($current:expr, $expected:expr) => {
             if let Some(current) = &$current {
                 if Some(current) != $expected.as_ref() {
-                    eprintln!(
+                    println!(
                         "WARNING: `llvm.{}` has no effect with `llvm.download-ci-llvm`. \
                         Current value: {:?}, Expected value(s): {}{:?}",
                         stringify!($expected).replace("_", "-"),
@@ -3112,7 +3112,7 @@ fn check_incompatible_options_for_ci_rustc(
         ($current:expr, $expected:expr, $config_section:expr) => {
             if let Some(current) = &$current {
                 if Some(current) != $expected.as_ref() {
-                    eprintln!(
+                    println!(
                         "WARNING: `{}` has no effect with `rust.download-rustc`. \
                         Current value: {:?}, Expected value(s): {}{:?}",
                         format!("{}.{}", $config_section, stringify!($expected).replace("_", "-")),

src/bootstrap/src/core/config/flags.rs

@@ -196,12 +196,12 @@ impl Flags {
         if let Ok(HelpVerboseOnly { help: true, verbose: 1.., cmd: subcommand }) =
             HelpVerboseOnly::try_parse_from(normalize_args(args))
         {
-            eprintln!("NOTE: updating submodules before printing available paths");
+            println!("NOTE: updating submodules before printing available paths");
             let config = Config::parse(Self::parse(&[String::from("build")]));
             let build = Build::new(config);
             let paths = Builder::get_help(&build, subcommand);
             if let Some(s) = paths {
-                eprintln!("{s}");
+                println!("{s}");
             } else {
                 panic!("No paths available for subcommand `{}`", subcommand.as_str());
             }

src/bootstrap/src/core/download.rs

@@ -77,7 +77,7 @@ impl Config {
         if self.dry_run() && !cmd.run_always {
             return true;
         }
-        self.verbose(|| eprintln!("running: {cmd:?}"));
+        self.verbose(|| println!("running: {cmd:?}"));
         check_run(cmd, self.is_verbose())
     }
 
@@ -144,7 +144,7 @@ impl Config {
     /// Please see <https://nixos.org/patchelf.html> for more information
     fn fix_bin_or_dylib(&self, fname: &Path) {
         assert_eq!(SHOULD_FIX_BINS_AND_DYLIBS.get(), Some(&true));
-        eprintln!("attempting to patch {}", fname.display());
+        println!("attempting to patch {}", fname.display());
 
         // Only build `.nix-deps` once.
         static NIX_DEPS_DIR: OnceLock<PathBuf> = OnceLock::new();
@@ -206,7 +206,7 @@ impl Config {
     }
 
     fn download_file(&self, url: &str, dest_path: &Path, help_on_error: &str) {
-        self.verbose(|| eprintln!("download {url}"));
+        self.verbose(|| println!("download {url}"));
         // Use a temporary file in case we crash while downloading, to avoid a corrupt download in cache/.
         let tempfile = self.tempdir().join(dest_path.file_name().unwrap());
         // While bootstrap itself only supports http and https downloads, downstream forks might
@@ -226,7 +226,7 @@ impl Config {
     }
 
     fn download_http_with_retries(&self, tempfile: &Path, url: &str, help_on_error: &str) {
-        eprintln!("downloading {url}");
+        println!("downloading {url}");
         // Try curl. If that fails and we are on windows, fallback to PowerShell.
         // options should be kept in sync with
         // src/bootstrap/src/core/download.rs
@@ -341,7 +341,7 @@ impl Config {
             short_path = short_path.strip_prefix(pattern).unwrap_or(short_path);
             let dst_path = dst.join(short_path);
             self.verbose(|| {
-                eprintln!("extracting {} to {}", original_path.display(), dst.display())
+                println!("extracting {} to {}", original_path.display(), dst.display())
             });
             if !t!(member.unpack_in(dst)) {
                 panic!("path traversal attack ??");
@@ -365,7 +365,7 @@ impl Config {
     pub(crate) fn verify(&self, path: &Path, expected: &str) -> bool {
         use sha2::Digest;
 
-        self.verbose(|| eprintln!("verifying {}", path.display()));
+        self.verbose(|| println!("verifying {}", path.display()));
 
         if self.dry_run() {
             return false;
@@ -391,7 +391,7 @@ impl Config {
         let verified = checksum == expected;
 
         if !verified {
-            eprintln!(
+            println!(
                 "invalid checksum: \n\
                 found:    {checksum}\n\
                 expected: {expected}",
@@ -421,7 +421,7 @@ enum DownloadSource {
 /// Functions that are only ever called once, but named for clarify and to avoid thousand-line functions.
 impl Config {
     pub(crate) fn download_clippy(&self) -> PathBuf {
-        self.verbose(|| eprintln!("downloading stage0 clippy artifacts"));
+        self.verbose(|| println!("downloading stage0 clippy artifacts"));
 
         let date = &self.stage0_metadata.compiler.date;
         let version = &self.stage0_metadata.compiler.version;
@@ -518,7 +518,7 @@ impl Config {
     }
 
     pub(crate) fn download_ci_rustc(&self, commit: &str) {
-        self.verbose(|| eprintln!("using downloaded stage2 artifacts from CI (commit {commit})"));
+        self.verbose(|| println!("using downloaded stage2 artifacts from CI (commit {commit})"));
 
         let version = self.artifact_version_part(commit);
         // download-rustc doesn't need its own cargo, it can just use beta's. But it does need the
@@ -539,7 +539,7 @@ impl Config {
 
     #[cfg(not(feature = "bootstrap-self-test"))]
     pub(crate) fn download_beta_toolchain(&self) {
-        self.verbose(|| eprintln!("downloading stage0 beta artifacts"));
+        self.verbose(|| println!("downloading stage0 beta artifacts"));
 
         let date = &self.stage0_metadata.compiler.date;
         let version = &self.stage0_metadata.compiler.version;
@@ -677,7 +677,7 @@ impl Config {
                     return;
                 } else {
                     self.verbose(|| {
-                        eprintln!(
+                        println!(
                             "ignoring cached file {} due to failed verification",
                             tarball.display()
                         )
@@ -776,10 +776,10 @@ download-rustc = false
                     t!(check_incompatible_options_for_ci_llvm(current_config_toml, ci_config_toml));
                 }
                 Err(e) if e.to_string().contains("unknown field") => {
-                    eprintln!(
+                    println!(
                         "WARNING: CI LLVM has some fields that are no longer supported in bootstrap; download-ci-llvm will be disabled."
                     );
-                    eprintln!("HELP: Consider rebasing to a newer commit if available.");
+                    println!("HELP: Consider rebasing to a newer commit if available.");
                 }
                 Err(e) => {
                     eprintln!("ERROR: Failed to parse CI LLVM config.toml: {e}");

src/bootstrap/src/core/sanity.rs

@@ -237,11 +237,11 @@ than building it.
                 stage0_supported_target_list.intersection(&missing_targets_hashset).collect();
 
             if !duplicated_targets.is_empty() {
-                eprintln!(
+                println!(
                     "Following targets supported from the stage0 compiler, please remove them from STAGE0_MISSING_TARGETS list."
                 );
                 for duplicated_target in duplicated_targets {
-                    eprintln!("  {duplicated_target}");
+                    println!("  {duplicated_target}");
                 }
                 std::process::exit(1);
             }

src/bootstrap/src/lib.rs

@@ -406,11 +406,11 @@ impl Build {
             .unwrap()
             .trim();
         if local_release.split('.').take(2).eq(version.split('.').take(2)) {
-            build.verbose(|| eprintln!("auto-detected local-rebuild {local_release}"));
+            build.verbose(|| println!("auto-detected local-rebuild {local_release}"));
             build.local_rebuild = true;
         }
 
-        build.verbose(|| eprintln!("finding compilers"));
+        build.verbose(|| println!("finding compilers"));
         utils::cc_detect::find(&build);
         // When running `setup`, the profile is about to change, so any requirements we have now may
         // be different on the next invocation. Don't check for them until the next time x.py is
@@ -418,7 +418,7 @@ impl Build {
         //
         // Similarly, for `setup` we don't actually need submodules or cargo metadata.
         if !matches!(build.config.cmd, Subcommand::Setup { .. }) {
-            build.verbose(|| eprintln!("running sanity check"));
+            build.verbose(|| println!("running sanity check"));
             crate::core::sanity::check(&mut build);
 
             // Make sure we update these before gathering metadata so we don't get an error about missing
@@ -436,7 +436,7 @@ impl Build {
             // Now, update all existing submodules.
             build.update_existing_submodules();
 
-            build.verbose(|| eprintln!("learning about cargo"));
+            build.verbose(|| println!("learning about cargo"));
             crate::core::metadata::build(&mut build);
         }
 
@@ -605,7 +605,7 @@ impl Build {
         let stamp = dir.join(".stamp");
         let mut cleared = false;
         if mtime(&stamp) < mtime(input) {
-            self.verbose(|| eprintln!("Dirty - {}", dir.display()));
+            self.verbose(|| println!("Dirty - {}", dir.display()));
             let _ = fs::remove_dir_all(dir);
             cleared = true;
         } else if stamp.exists() {
@@ -890,7 +890,7 @@ impl Build {
         let executed_at = std::panic::Location::caller();
 
         self.verbose(|| {
-            eprintln!("running: {command:?} (created at {created_at}, executed at {executed_at})")
+            println!("running: {command:?} (created at {created_at}, executed at {executed_at})")
         });
 
         let cmd = command.as_command_mut();
@@ -947,7 +947,7 @@ Executed at: {executed_at}"#,
 
         let fail = |message: &str, output: CommandOutput| -> ! {
             if self.is_verbose() {
-                eprintln!("{message}");
+                println!("{message}");
             } else {
                 let (stdout, stderr) = (output.stdout_if_present(), output.stderr_if_present());
                 // If the command captures output, the user would not see any indication that
@@ -957,16 +957,16 @@ Executed at: {executed_at}"#,
                     if let Some(stdout) =
                         output.stdout_if_present().take_if(|s| !s.trim().is_empty())
                     {
-                        eprintln!("STDOUT:\n{stdout}\n");
+                        println!("STDOUT:\n{stdout}\n");
                     }
                     if let Some(stderr) =
                         output.stderr_if_present().take_if(|s| !s.trim().is_empty())
                     {
-                        eprintln!("STDERR:\n{stderr}\n");
+                        println!("STDERR:\n{stderr}\n");
                     }
-                    eprintln!("Command {command:?} has failed. Rerun with -v to see more details.");
+                    println!("Command {command:?} has failed. Rerun with -v to see more details.");
                 } else {
-                    eprintln!("Command has failed. Rerun with -v to see more details.");
+                    println!("Command has failed. Rerun with -v to see more details.");
                 }
             }
             exit!(1);
@@ -1011,7 +1011,7 @@ Executed at: {executed_at}"#,
         match self.config.dry_run {
             DryRun::SelfCheck => (),
             DryRun::Disabled | DryRun::UserSelected => {
-                eprintln!("{msg}");
+                println!("{msg}");
             }
         }
     }
@@ -1666,7 +1666,7 @@ Executed at: {executed_at}"#,
         if self.config.dry_run() {
             return;
         }
-        self.verbose_than(1, || eprintln!("Copy/Link {src:?} to {dst:?}"));
+        self.verbose_than(1, || println!("Copy/Link {src:?} to {dst:?}"));
         if src == dst {
             return;
         }
@@ -1775,7 +1775,7 @@ Executed at: {executed_at}"#,
             return;
         }
         let dst = dstdir.join(src.file_name().unwrap());
-        self.verbose_than(1, || eprintln!("Install {src:?} to {dst:?}"));
+        self.verbose_than(1, || println!("Install {src:?} to {dst:?}"));
         t!(fs::create_dir_all(dstdir));
         if !src.exists() {
             panic!("ERROR: File \"{}\" not found!", src.display());

src/bootstrap/src/utils/cc_detect.rs

@@ -155,15 +155,15 @@ pub fn find_target(build: &Build, target: TargetSelection) {
         build.cxx.borrow_mut().insert(target, compiler);
     }
 
-    build.verbose(|| eprintln!("CC_{} = {:?}", target.triple, build.cc(target)));
-    build.verbose(|| eprintln!("CFLAGS_{} = {cflags:?}", target.triple));
+    build.verbose(|| println!("CC_{} = {:?}", target.triple, build.cc(target)));
+    build.verbose(|| println!("CFLAGS_{} = {cflags:?}", target.triple));
     if let Ok(cxx) = build.cxx(target) {
         let cxxflags = build.cflags(target, GitRepo::Rustc, CLang::Cxx);
-        build.verbose(|| eprintln!("CXX_{} = {cxx:?}", target.triple));
-        build.verbose(|| eprintln!("CXXFLAGS_{} = {cxxflags:?}", target.triple));
+        build.verbose(|| println!("CXX_{} = {cxx:?}", target.triple));
+        build.verbose(|| println!("CXXFLAGS_{} = {cxxflags:?}", target.triple));
     }
     if let Some(ar) = ar {
-        build.verbose(|| eprintln!("AR_{} = {ar:?}", target.triple));
+        build.verbose(|| println!("AR_{} = {ar:?}", target.triple));
         build.ar.borrow_mut().insert(target, ar);
     }
 

src/bootstrap/src/utils/helpers.rs

@@ -135,7 +135,7 @@ impl Drop for TimeIt {
     fn drop(&mut self) {
         let time = self.1.elapsed();
         if !self.0 {
-            eprintln!("\tfinished in {}.{:03} seconds", time.as_secs(), time.subsec_millis());
+            println!("\tfinished in {}.{:03} seconds", time.as_secs(), time.subsec_millis());
         }
     }
 }
@@ -267,12 +267,12 @@ pub fn check_run(cmd: &mut BootstrapCommand, print_cmd_on_fail: bool) -> bool {
     let status = match cmd.as_command_mut().status() {
         Ok(status) => status,
         Err(e) => {
-            eprintln!("failed to execute command: {cmd:?}\nERROR: {e}");
+            println!("failed to execute command: {cmd:?}\nERROR: {e}");
             return false;
         }
     };
     if !status.success() && print_cmd_on_fail {
-        eprintln!(
+        println!(
             "\n\ncommand did not execute successfully: {cmd:?}\n\
              expected success, got: {status}\n\n"
         );

src/bootstrap/src/utils/metrics.rs

@@ -185,7 +185,7 @@ impl BuildMetrics {
                 if version.format_version == CURRENT_FORMAT_VERSION {
                     t!(serde_json::from_slice::<JsonRoot>(&contents)).invocations
                 } else {
-                    eprintln!(
+                    println!(
                         "WARNING: overriding existing build/metrics.json, as it's not \
                          compatible with build metrics format version {CURRENT_FORMAT_VERSION}."
                     );

src/bootstrap/src/utils/render_tests.rs

@@ -56,7 +56,7 @@ fn run_tests(builder: &Builder<'_>, cmd: &mut BootstrapCommand, stream: bool) ->
     let cmd = cmd.as_command_mut();
     cmd.stdout(Stdio::piped());
 
-    builder.verbose(|| eprintln!("running: {cmd:?}"));
+    builder.verbose(|| println!("running: {cmd:?}"));
 
     let mut process = cmd.spawn().unwrap();
 
@@ -71,7 +71,7 @@ fn run_tests(builder: &Builder<'_>, cmd: &mut BootstrapCommand, stream: bool) ->
 
     let result = process.wait_with_output().unwrap();
     if !result.status.success() && builder.is_verbose() {
-        eprintln!(
+        println!(
             "\n\ncommand did not execute successfully: {cmd:?}\n\
              expected success, got: {}",
             result.status
@@ -135,9 +135,7 @@ impl<'a> Renderer<'a> {
         if self.up_to_date_tests > 0 {
             let n = self.up_to_date_tests;
             let s = if n > 1 { "s" } else { "" };
-            eprintln!(
-                "help: ignored {n} up-to-date test{s}; use `--force-rerun` to prevent this\n"
-            );
+            println!("help: ignored {n} up-to-date test{s}; use `--force-rerun` to prevent this\n");
         }
     }
 
@@ -192,7 +190,7 @@ impl<'a> Renderer<'a> {
         if let Some(exec_time) = test.exec_time {
             print!(" ({exec_time:.2?})");
         }
-        eprintln!();
+        println!();
     }
 
     fn render_test_outcome_terse(&mut self, outcome: Outcome<'_>, test: &TestOutcome) {
@@ -202,7 +200,7 @@ impl<'a> Renderer<'a> {
                 let executed = format!("{:>width$}", self.executed_tests - 1, width = total.len());
                 print!(" {executed}/{total}");
             }
-            eprintln!();
+            println!();
             self.terse_tests_in_line = 0;
         }
 
@@ -214,31 +212,31 @@ impl<'a> Renderer<'a> {
     fn render_suite_outcome(&self, outcome: Outcome<'_>, suite: &SuiteOutcome) {
         // The terse output doesn't end with a newline, so we need to add it ourselves.
         if !self.builder.config.verbose_tests {
-            eprintln!();
+            println!();
         }
 
         if !self.failures.is_empty() {
-            eprintln!("\nfailures:\n");
+            println!("\nfailures:\n");
             for failure in &self.failures {
                 if failure.stdout.is_some() || failure.message.is_some() {
-                    eprintln!("---- {} stdout ----", failure.name);
+                    println!("---- {} stdout ----", failure.name);
                     if let Some(stdout) = &failure.stdout {
-                        eprintln!("{stdout}");
+                        println!("{stdout}");
                     }
                     if let Some(message) = &failure.message {
-                        eprintln!("NOTE: {message}");
+                        println!("NOTE: {message}");
                     }
                 }
             }
 
-            eprintln!("\nfailures:");
+            println!("\nfailures:");
             for failure in &self.failures {
-                eprintln!("    {}", failure.name);
+                println!("    {}", failure.name);
             }
         }
 
         if !self.benches.is_empty() {
-            eprintln!("\nbenchmarks:");
+            println!("\nbenchmarks:");
 
             let mut rows = Vec::new();
             for bench in &self.benches {
@@ -253,13 +251,13 @@ impl<'a> Renderer<'a> {
             let max_1 = rows.iter().map(|r| r.1.len()).max().unwrap_or(0);
             let max_2 = rows.iter().map(|r| r.2.len()).max().unwrap_or(0);
             for row in &rows {
-                eprintln!("    {:<max_0$} {:>max_1$} {:>max_2$}", row.0, row.1, row.2);
+                println!("    {:<max_0$} {:>max_1$} {:>max_2$}", row.0, row.1, row.2);
             }
         }
 
         print!("\ntest result: ");
         self.builder.colored_stdout(|stdout| outcome.write_long(stdout)).unwrap();
-        eprintln!(
+        println!(
             ". {} passed; {} failed; {} ignored; {} measured; {} filtered out{time}\n",
             suite.passed,
             suite.failed,
@@ -276,7 +274,7 @@ impl<'a> Renderer<'a> {
     fn render_message(&mut self, message: Message) {
         match message {
             Message::Suite(SuiteMessage::Started { test_count }) => {
-                eprintln!("\nrunning {test_count} tests");
+                println!("\nrunning {test_count} tests");
                 self.executed_tests = 0;
                 self.terse_tests_in_line = 0;
                 self.tests_count = Some(test_count);
@@ -316,7 +314,7 @@ impl<'a> Renderer<'a> {
                 self.failures.push(outcome);
             }
             Message::Test(TestMessage::Timeout { name }) => {
-                eprintln!("test {name} has been running for a long time");
+                println!("test {name} has been running for a long time");
             }
             Message::Test(TestMessage::Started) => {} // Not useful
         }

src/bootstrap/src/utils/tarball.rs

@@ -344,7 +344,7 @@ impl<'a> Tarball<'a> {
         // For `x install` tarball files aren't needed, so we can speed up the process by not producing them.
         let compression_profile = if self.builder.kind == Kind::Install {
             self.builder.verbose(|| {
-                eprintln!("Forcing dist.compression-profile = 'no-op' for `x install`.")
+                println!("Forcing dist.compression-profile = 'no-op' for `x install`.")
             });
             // "no-op" indicates that the rust-installer won't produce compressed tarball sources.
             "no-op"

src/doc/book

@@ -1 +1 @@
-Subproject commit e16dd73690a6cc3ecdc5f5d94bbc3ce158a42e16
+Subproject commit 614c19cb4025636eb2ba68ebb3d44e3bd3a5e6e4

src/doc/edition-guide

@@ -1 +1 @@
-Subproject commit f48b0e842a3911c63240e955d042089e9e0894c7
+Subproject commit 128669297c8a7fdf771042eaec18b8adfaeaf0cd

src/doc/reference

@@ -1 +1 @@
-Subproject commit 5c86c739ec71b8bc839310ff47fa94e94635bba9
+Subproject commit ede56d1bbe132bac476b5029cd6d7508ca9572e9

src/doc/rustc-dev-guide

@@ -1 +1 @@
-Subproject commit 787b4166ccc67bd8f72a6e3ef6685ce9ce82909a
+Subproject commit b21d99b770f9aceb0810c843847c52f86f45d2ed

src/tools/clippy/clippy_lints/src/declared_lints.rs

@@ -744,7 +744,6 @@ pub static LINTS: &[&crate::LintInfo] = &[
     crate::unit_types::LET_UNIT_VALUE_INFO,
     crate::unit_types::UNIT_ARG_INFO,
     crate::unit_types::UNIT_CMP_INFO,
-    crate::unnamed_address::FN_ADDRESS_COMPARISONS_INFO,
     crate::unnecessary_box_returns::UNNECESSARY_BOX_RETURNS_INFO,
     crate::unnecessary_literal_bound::UNNECESSARY_LITERAL_BOUND_INFO,
     crate::unnecessary_map_on_constructor::UNNECESSARY_MAP_ON_CONSTRUCTOR_INFO,

src/tools/clippy/clippy_lints/src/deprecated_lints.rs

@@ -74,6 +74,8 @@ declare_with_version! { RENAMED(RENAMED_VERSION): &[(&str, &str)] = &[
     #[clippy::version = "1.53.0"]
     ("clippy::filter_map", "clippy::manual_filter_map"),
     #[clippy::version = ""]
+    ("clippy::fn_address_comparisons", "unpredictable_function_pointer_comparisons"),
+    #[clippy::version = ""]
     ("clippy::identity_conversion", "clippy::useless_conversion"),
     #[clippy::version = "pre 1.29.0"]
     ("clippy::if_let_redundant_pattern_matching", "clippy::redundant_pattern_matching"),

src/tools/clippy/clippy_lints/src/lib.rs

@@ -363,7 +363,6 @@ mod uninhabited_references;
 mod uninit_vec;
 mod unit_return_expecting_ord;
 mod unit_types;
-mod unnamed_address;
 mod unnecessary_box_returns;
 mod unnecessary_literal_bound;
 mod unnecessary_map_on_constructor;
@@ -786,7 +785,6 @@ pub fn register_lints(store: &mut rustc_lint::LintStore, conf: &'static Conf) {
     store.register_early_pass(|| Box::new(option_env_unwrap::OptionEnvUnwrap));
     store.register_late_pass(move |_| Box::new(wildcard_imports::WildcardImports::new(conf)));
     store.register_late_pass(|_| Box::<redundant_pub_crate::RedundantPubCrate>::default());
-    store.register_late_pass(|_| Box::new(unnamed_address::UnnamedAddress));
     store.register_late_pass(|_| Box::<dereference::Dereferencing<'_>>::default());
     store.register_late_pass(|_| Box::new(option_if_let_else::OptionIfLetElse));
     store.register_late_pass(|_| Box::new(future_not_send::FutureNotSend));

src/tools/clippy/clippy_lints/src/unnamed_address.rs

@@ -1,60 +0,0 @@
-use clippy_utils::diagnostics::span_lint;
-use rustc_hir::{BinOpKind, Expr, ExprKind};
-use rustc_lint::{LateContext, LateLintPass};
-use rustc_middle::ty;
-use rustc_session::declare_lint_pass;
-
-declare_clippy_lint! {
-    /// ### What it does
-    /// Checks for comparisons with an address of a function item.
-    ///
-    /// ### Why is this bad?
-    /// Function item address is not guaranteed to be unique and could vary
-    /// between different code generation units. Furthermore different function items could have
-    /// the same address after being merged together.
-    ///
-    /// ### Example
-    /// ```no_run
-    /// type F = fn();
-    /// fn a() {}
-    /// let f: F = a;
-    /// if f == a {
-    ///     // ...
-    /// }
-    /// ```
-    #[clippy::version = "1.44.0"]
-    pub FN_ADDRESS_COMPARISONS,
-    correctness,
-    "comparison with an address of a function item"
-}
-
-declare_lint_pass!(UnnamedAddress => [FN_ADDRESS_COMPARISONS]);
-
-impl LateLintPass<'_> for UnnamedAddress {
-    fn check_expr(&mut self, cx: &LateContext<'_>, expr: &Expr<'_>) {
-        fn is_comparison(binop: BinOpKind) -> bool {
-            matches!(
-                binop,
-                BinOpKind::Eq | BinOpKind::Lt | BinOpKind::Le | BinOpKind::Ne | BinOpKind::Ge | BinOpKind::Gt
-            )
-        }
-
-        fn is_fn_def(cx: &LateContext<'_>, expr: &Expr<'_>) -> bool {
-            matches!(cx.typeck_results().expr_ty(expr).kind(), ty::FnDef(..))
-        }
-
-        if let ExprKind::Binary(binop, left, right) = expr.kind
-            && is_comparison(binop.node)
-            && cx.typeck_results().expr_ty_adjusted(left).is_fn_ptr()
-            && cx.typeck_results().expr_ty_adjusted(right).is_fn_ptr()
-            && (is_fn_def(cx, left) || is_fn_def(cx, right))
-        {
-            span_lint(
-                cx,
-                FN_ADDRESS_COMPARISONS,
-                expr.span,
-                "comparing with a non-unique address of a function item",
-            );
-        }
-    }
-}

src/tools/clippy/tests/ui/fn_address_comparisons.rs

@@ -1,23 +0,0 @@
-use std::fmt::Debug;
-use std::ptr;
-use std::rc::Rc;
-use std::sync::Arc;
-
-fn a() {}
-
-#[warn(clippy::fn_address_comparisons)]
-fn main() {
-    type F = fn();
-    let f: F = a;
-    let g: F = f;
-
-    // These should fail:
-    let _ = f == a;
-    //~^ ERROR: comparing with a non-unique address of a function item
-    //~| NOTE: `-D clippy::fn-address-comparisons` implied by `-D warnings`
-    let _ = f != a;
-    //~^ ERROR: comparing with a non-unique address of a function item
-
-    // These should be fine:
-    let _ = f == g;
-}

src/tools/clippy/tests/ui/fn_address_comparisons.stderr

@@ -1,17 +0,0 @@
-error: comparing with a non-unique address of a function item
-  --> tests/ui/fn_address_comparisons.rs:15:13
-   |
-LL |     let _ = f == a;
-   |             ^^^^^^
-   |
-   = note: `-D clippy::fn-address-comparisons` implied by `-D warnings`
-   = help: to override `-D warnings` add `#[allow(clippy::fn_address_comparisons)]`
-
-error: comparing with a non-unique address of a function item
-  --> tests/ui/fn_address_comparisons.rs:18:13
-   |
-LL |     let _ = f != a;
-   |             ^^^^^^
-
-error: aborting due to 2 previous errors
-

src/tools/clippy/tests/ui/rename.fixed

@@ -59,6 +59,7 @@
 #![allow(unknown_lints)]
 #![allow(unused_labels)]
 #![allow(ambiguous_wide_pointer_comparisons)]
+#![allow(unpredictable_function_pointer_comparisons)]
 #![allow(clippy::reversed_empty_ranges)]
 #![warn(clippy::almost_complete_range)] //~ ERROR: lint `clippy::almost_complete_letter_range`
 #![warn(clippy::disallowed_names)] //~ ERROR: lint `clippy::blacklisted_name`
@@ -74,6 +75,7 @@
 #![warn(clippy::mixed_read_write_in_expression)] //~ ERROR: lint `clippy::eval_order_dependence`
 #![warn(clippy::manual_find_map)] //~ ERROR: lint `clippy::find_map`
 #![warn(clippy::manual_filter_map)] //~ ERROR: lint `clippy::filter_map`
+#![warn(unpredictable_function_pointer_comparisons)] //~ ERROR: lint `clippy::fn_address_comparisons`
 #![warn(clippy::useless_conversion)] //~ ERROR: lint `clippy::identity_conversion`
 #![warn(clippy::redundant_pattern_matching)] //~ ERROR: lint `clippy::if_let_redundant_pattern_matching`
 #![warn(clippy::match_result_ok)] //~ ERROR: lint `clippy::if_let_some_result`

src/tools/clippy/tests/ui/rename.rs

@@ -59,6 +59,7 @@
 #![allow(unknown_lints)]
 #![allow(unused_labels)]
 #![allow(ambiguous_wide_pointer_comparisons)]
+#![allow(unpredictable_function_pointer_comparisons)]
 #![allow(clippy::reversed_empty_ranges)]
 #![warn(clippy::almost_complete_letter_range)] //~ ERROR: lint `clippy::almost_complete_letter_range`
 #![warn(clippy::blacklisted_name)] //~ ERROR: lint `clippy::blacklisted_name`
@@ -74,6 +75,7 @@
 #![warn(clippy::eval_order_dependence)] //~ ERROR: lint `clippy::eval_order_dependence`
 #![warn(clippy::find_map)] //~ ERROR: lint `clippy::find_map`
 #![warn(clippy::filter_map)] //~ ERROR: lint `clippy::filter_map`
+#![warn(clippy::fn_address_comparisons)] //~ ERROR: lint `clippy::fn_address_comparisons`
 #![warn(clippy::identity_conversion)] //~ ERROR: lint `clippy::identity_conversion`
 #![warn(clippy::if_let_redundant_pattern_matching)] //~ ERROR: lint `clippy::if_let_redundant_pattern_matching`
 #![warn(clippy::if_let_some_result)] //~ ERROR: lint `clippy::if_let_some_result`

src/tools/clippy/tests/ui/rename.stderr

@@ -1,5 +1,5 @@
 error: lint `clippy::almost_complete_letter_range` has been renamed to `clippy::almost_complete_range`
-  --> tests/ui/rename.rs:63:9
+  --> tests/ui/rename.rs:64:9
    |
 LL | #![warn(clippy::almost_complete_letter_range)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::almost_complete_range`
@@ -8,394 +8,400 @@ LL | #![warn(clippy::almost_complete_letter_range)]
    = help: to override `-D warnings` add `#[allow(renamed_and_removed_lints)]`
 
 error: lint `clippy::blacklisted_name` has been renamed to `clippy::disallowed_names`
-  --> tests/ui/rename.rs:64:9
+  --> tests/ui/rename.rs:65:9
    |
 LL | #![warn(clippy::blacklisted_name)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::disallowed_names`
 
 error: lint `clippy::block_in_if_condition_expr` has been renamed to `clippy::blocks_in_conditions`
-  --> tests/ui/rename.rs:65:9
+  --> tests/ui/rename.rs:66:9
    |
 LL | #![warn(clippy::block_in_if_condition_expr)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::blocks_in_conditions`
 
 error: lint `clippy::block_in_if_condition_stmt` has been renamed to `clippy::blocks_in_conditions`
-  --> tests/ui/rename.rs:66:9
+  --> tests/ui/rename.rs:67:9
    |
 LL | #![warn(clippy::block_in_if_condition_stmt)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::blocks_in_conditions`
 
 error: lint `clippy::blocks_in_if_conditions` has been renamed to `clippy::blocks_in_conditions`
-  --> tests/ui/rename.rs:67:9
+  --> tests/ui/rename.rs:68:9
    |
 LL | #![warn(clippy::blocks_in_if_conditions)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::blocks_in_conditions`
 
 error: lint `clippy::box_vec` has been renamed to `clippy::box_collection`
-  --> tests/ui/rename.rs:68:9
+  --> tests/ui/rename.rs:69:9
    |
 LL | #![warn(clippy::box_vec)]
    |         ^^^^^^^^^^^^^^^ help: use the new name: `clippy::box_collection`
 
 error: lint `clippy::const_static_lifetime` has been renamed to `clippy::redundant_static_lifetimes`
-  --> tests/ui/rename.rs:69:9
+  --> tests/ui/rename.rs:70:9
    |
 LL | #![warn(clippy::const_static_lifetime)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::redundant_static_lifetimes`
 
 error: lint `clippy::cyclomatic_complexity` has been renamed to `clippy::cognitive_complexity`
-  --> tests/ui/rename.rs:70:9
+  --> tests/ui/rename.rs:71:9
    |
 LL | #![warn(clippy::cyclomatic_complexity)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::cognitive_complexity`
 
 error: lint `clippy::derive_hash_xor_eq` has been renamed to `clippy::derived_hash_with_manual_eq`
-  --> tests/ui/rename.rs:71:9
+  --> tests/ui/rename.rs:72:9
    |
 LL | #![warn(clippy::derive_hash_xor_eq)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::derived_hash_with_manual_eq`
 
 error: lint `clippy::disallowed_method` has been renamed to `clippy::disallowed_methods`
-  --> tests/ui/rename.rs:72:9
+  --> tests/ui/rename.rs:73:9
    |
 LL | #![warn(clippy::disallowed_method)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::disallowed_methods`
 
 error: lint `clippy::disallowed_type` has been renamed to `clippy::disallowed_types`
-  --> tests/ui/rename.rs:73:9
+  --> tests/ui/rename.rs:74:9
    |
 LL | #![warn(clippy::disallowed_type)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::disallowed_types`
 
 error: lint `clippy::eval_order_dependence` has been renamed to `clippy::mixed_read_write_in_expression`
-  --> tests/ui/rename.rs:74:9
+  --> tests/ui/rename.rs:75:9
    |
 LL | #![warn(clippy::eval_order_dependence)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::mixed_read_write_in_expression`
 
 error: lint `clippy::find_map` has been renamed to `clippy::manual_find_map`
-  --> tests/ui/rename.rs:75:9
+  --> tests/ui/rename.rs:76:9
    |
 LL | #![warn(clippy::find_map)]
    |         ^^^^^^^^^^^^^^^^ help: use the new name: `clippy::manual_find_map`
 
 error: lint `clippy::filter_map` has been renamed to `clippy::manual_filter_map`
-  --> tests/ui/rename.rs:76:9
+  --> tests/ui/rename.rs:77:9
    |
 LL | #![warn(clippy::filter_map)]
    |         ^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::manual_filter_map`
 
+error: lint `clippy::fn_address_comparisons` has been renamed to `unpredictable_function_pointer_comparisons`
+  --> tests/ui/rename.rs:78:9
+   |
+LL | #![warn(clippy::fn_address_comparisons)]
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `unpredictable_function_pointer_comparisons`
+
 error: lint `clippy::identity_conversion` has been renamed to `clippy::useless_conversion`
-  --> tests/ui/rename.rs:77:9
+  --> tests/ui/rename.rs:79:9
    |
 LL | #![warn(clippy::identity_conversion)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::useless_conversion`
 
 error: lint `clippy::if_let_redundant_pattern_matching` has been renamed to `clippy::redundant_pattern_matching`
-  --> tests/ui/rename.rs:78:9
+  --> tests/ui/rename.rs:80:9
    |
 LL | #![warn(clippy::if_let_redundant_pattern_matching)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::redundant_pattern_matching`
 
 error: lint `clippy::if_let_some_result` has been renamed to `clippy::match_result_ok`
-  --> tests/ui/rename.rs:79:9
+  --> tests/ui/rename.rs:81:9
    |
 LL | #![warn(clippy::if_let_some_result)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::match_result_ok`
 
 error: lint `clippy::incorrect_clone_impl_on_copy_type` has been renamed to `clippy::non_canonical_clone_impl`
-  --> tests/ui/rename.rs:80:9
+  --> tests/ui/rename.rs:82:9
    |
 LL | #![warn(clippy::incorrect_clone_impl_on_copy_type)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::non_canonical_clone_impl`
 
 error: lint `clippy::incorrect_partial_ord_impl_on_ord_type` has been renamed to `clippy::non_canonical_partial_ord_impl`
-  --> tests/ui/rename.rs:81:9
+  --> tests/ui/rename.rs:83:9
    |
 LL | #![warn(clippy::incorrect_partial_ord_impl_on_ord_type)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::non_canonical_partial_ord_impl`
 
 error: lint `clippy::integer_arithmetic` has been renamed to `clippy::arithmetic_side_effects`
-  --> tests/ui/rename.rs:82:9
+  --> tests/ui/rename.rs:84:9
    |
 LL | #![warn(clippy::integer_arithmetic)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::arithmetic_side_effects`
 
 error: lint `clippy::logic_bug` has been renamed to `clippy::overly_complex_bool_expr`
-  --> tests/ui/rename.rs:83:9
+  --> tests/ui/rename.rs:85:9
    |
 LL | #![warn(clippy::logic_bug)]
    |         ^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::overly_complex_bool_expr`
 
 error: lint `clippy::new_without_default_derive` has been renamed to `clippy::new_without_default`
-  --> tests/ui/rename.rs:84:9
+  --> tests/ui/rename.rs:86:9
    |
 LL | #![warn(clippy::new_without_default_derive)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::new_without_default`
 
 error: lint `clippy::option_and_then_some` has been renamed to `clippy::bind_instead_of_map`
-  --> tests/ui/rename.rs:85:9
+  --> tests/ui/rename.rs:87:9
    |
 LL | #![warn(clippy::option_and_then_some)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::bind_instead_of_map`
 
 error: lint `clippy::option_expect_used` has been renamed to `clippy::expect_used`
-  --> tests/ui/rename.rs:86:9
+  --> tests/ui/rename.rs:88:9
    |
 LL | #![warn(clippy::option_expect_used)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::expect_used`
 
 error: lint `clippy::option_map_unwrap_or` has been renamed to `clippy::map_unwrap_or`
-  --> tests/ui/rename.rs:87:9
+  --> tests/ui/rename.rs:89:9
    |
 LL | #![warn(clippy::option_map_unwrap_or)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::map_unwrap_or`
 
 error: lint `clippy::option_map_unwrap_or_else` has been renamed to `clippy::map_unwrap_or`
-  --> tests/ui/rename.rs:88:9
+  --> tests/ui/rename.rs:90:9
    |
 LL | #![warn(clippy::option_map_unwrap_or_else)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::map_unwrap_or`
 
 error: lint `clippy::option_unwrap_used` has been renamed to `clippy::unwrap_used`
-  --> tests/ui/rename.rs:89:9
+  --> tests/ui/rename.rs:91:9
    |
 LL | #![warn(clippy::option_unwrap_used)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::unwrap_used`
 
 error: lint `clippy::overflow_check_conditional` has been renamed to `clippy::panicking_overflow_checks`
-  --> tests/ui/rename.rs:90:9
+  --> tests/ui/rename.rs:92:9
    |
 LL | #![warn(clippy::overflow_check_conditional)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::panicking_overflow_checks`
 
 error: lint `clippy::ref_in_deref` has been renamed to `clippy::needless_borrow`
-  --> tests/ui/rename.rs:91:9
+  --> tests/ui/rename.rs:93:9
    |
 LL | #![warn(clippy::ref_in_deref)]
    |         ^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::needless_borrow`
 
 error: lint `clippy::result_expect_used` has been renamed to `clippy::expect_used`
-  --> tests/ui/rename.rs:92:9
+  --> tests/ui/rename.rs:94:9
    |
 LL | #![warn(clippy::result_expect_used)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::expect_used`
 
 error: lint `clippy::result_map_unwrap_or_else` has been renamed to `clippy::map_unwrap_or`
-  --> tests/ui/rename.rs:93:9
+  --> tests/ui/rename.rs:95:9
    |
 LL | #![warn(clippy::result_map_unwrap_or_else)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::map_unwrap_or`
 
 error: lint `clippy::result_unwrap_used` has been renamed to `clippy::unwrap_used`
-  --> tests/ui/rename.rs:94:9
+  --> tests/ui/rename.rs:96:9
    |
 LL | #![warn(clippy::result_unwrap_used)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::unwrap_used`
 
 error: lint `clippy::single_char_push_str` has been renamed to `clippy::single_char_add_str`
-  --> tests/ui/rename.rs:95:9
+  --> tests/ui/rename.rs:97:9
    |
 LL | #![warn(clippy::single_char_push_str)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::single_char_add_str`
 
 error: lint `clippy::stutter` has been renamed to `clippy::module_name_repetitions`
-  --> tests/ui/rename.rs:96:9
+  --> tests/ui/rename.rs:98:9
    |
 LL | #![warn(clippy::stutter)]
    |         ^^^^^^^^^^^^^^^ help: use the new name: `clippy::module_name_repetitions`
 
 error: lint `clippy::thread_local_initializer_can_be_made_const` has been renamed to `clippy::missing_const_for_thread_local`
-  --> tests/ui/rename.rs:97:9
+  --> tests/ui/rename.rs:99:9
    |
 LL | #![warn(clippy::thread_local_initializer_can_be_made_const)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::missing_const_for_thread_local`
 
 error: lint `clippy::to_string_in_display` has been renamed to `clippy::recursive_format_impl`
-  --> tests/ui/rename.rs:98:9
+  --> tests/ui/rename.rs:100:9
    |
 LL | #![warn(clippy::to_string_in_display)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::recursive_format_impl`
 
 error: lint `clippy::unwrap_or_else_default` has been renamed to `clippy::unwrap_or_default`
-  --> tests/ui/rename.rs:99:9
+  --> tests/ui/rename.rs:101:9
    |
 LL | #![warn(clippy::unwrap_or_else_default)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::unwrap_or_default`
 
 error: lint `clippy::zero_width_space` has been renamed to `clippy::invisible_characters`
-  --> tests/ui/rename.rs:100:9
+  --> tests/ui/rename.rs:102:9
    |
 LL | #![warn(clippy::zero_width_space)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::invisible_characters`
 
 error: lint `clippy::cast_ref_to_mut` has been renamed to `invalid_reference_casting`
-  --> tests/ui/rename.rs:101:9
+  --> tests/ui/rename.rs:103:9
    |
 LL | #![warn(clippy::cast_ref_to_mut)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `invalid_reference_casting`
 
 error: lint `clippy::clone_double_ref` has been renamed to `suspicious_double_ref_op`
-  --> tests/ui/rename.rs:102:9
+  --> tests/ui/rename.rs:104:9
    |
 LL | #![warn(clippy::clone_double_ref)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `suspicious_double_ref_op`
 
 error: lint `clippy::cmp_nan` has been renamed to `invalid_nan_comparisons`
-  --> tests/ui/rename.rs:103:9
+  --> tests/ui/rename.rs:105:9
    |
 LL | #![warn(clippy::cmp_nan)]
    |         ^^^^^^^^^^^^^^^ help: use the new name: `invalid_nan_comparisons`
 
 error: lint `clippy::drop_bounds` has been renamed to `drop_bounds`
-  --> tests/ui/rename.rs:104:9
+  --> tests/ui/rename.rs:106:9
    |
 LL | #![warn(clippy::drop_bounds)]
    |         ^^^^^^^^^^^^^^^^^^^ help: use the new name: `drop_bounds`
 
 error: lint `clippy::drop_copy` has been renamed to `dropping_copy_types`
-  --> tests/ui/rename.rs:105:9
+  --> tests/ui/rename.rs:107:9
    |
 LL | #![warn(clippy::drop_copy)]
    |         ^^^^^^^^^^^^^^^^^ help: use the new name: `dropping_copy_types`
 
 error: lint `clippy::drop_ref` has been renamed to `dropping_references`
-  --> tests/ui/rename.rs:106:9
+  --> tests/ui/rename.rs:108:9
    |
 LL | #![warn(clippy::drop_ref)]
    |         ^^^^^^^^^^^^^^^^ help: use the new name: `dropping_references`
 
 error: lint `clippy::fn_null_check` has been renamed to `useless_ptr_null_checks`
-  --> tests/ui/rename.rs:107:9
+  --> tests/ui/rename.rs:109:9
    |
 LL | #![warn(clippy::fn_null_check)]
    |         ^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `useless_ptr_null_checks`
 
 error: lint `clippy::for_loop_over_option` has been renamed to `for_loops_over_fallibles`
-  --> tests/ui/rename.rs:108:9
+  --> tests/ui/rename.rs:110:9
    |
 LL | #![warn(clippy::for_loop_over_option)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `for_loops_over_fallibles`
 
 error: lint `clippy::for_loop_over_result` has been renamed to `for_loops_over_fallibles`
-  --> tests/ui/rename.rs:109:9
+  --> tests/ui/rename.rs:111:9
    |
 LL | #![warn(clippy::for_loop_over_result)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `for_loops_over_fallibles`
 
 error: lint `clippy::for_loops_over_fallibles` has been renamed to `for_loops_over_fallibles`
-  --> tests/ui/rename.rs:110:9
+  --> tests/ui/rename.rs:112:9
    |
 LL | #![warn(clippy::for_loops_over_fallibles)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `for_loops_over_fallibles`
 
 error: lint `clippy::forget_copy` has been renamed to `forgetting_copy_types`
-  --> tests/ui/rename.rs:111:9
+  --> tests/ui/rename.rs:113:9
    |
 LL | #![warn(clippy::forget_copy)]
    |         ^^^^^^^^^^^^^^^^^^^ help: use the new name: `forgetting_copy_types`
 
 error: lint `clippy::forget_ref` has been renamed to `forgetting_references`
-  --> tests/ui/rename.rs:112:9
+  --> tests/ui/rename.rs:114:9
    |
 LL | #![warn(clippy::forget_ref)]
    |         ^^^^^^^^^^^^^^^^^^ help: use the new name: `forgetting_references`
 
 error: lint `clippy::into_iter_on_array` has been renamed to `array_into_iter`
-  --> tests/ui/rename.rs:113:9
+  --> tests/ui/rename.rs:115:9
    |
 LL | #![warn(clippy::into_iter_on_array)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `array_into_iter`
 
 error: lint `clippy::invalid_atomic_ordering` has been renamed to `invalid_atomic_ordering`
-  --> tests/ui/rename.rs:114:9
+  --> tests/ui/rename.rs:116:9
    |
 LL | #![warn(clippy::invalid_atomic_ordering)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `invalid_atomic_ordering`
 
 error: lint `clippy::invalid_ref` has been renamed to `invalid_value`
-  --> tests/ui/rename.rs:115:9
+  --> tests/ui/rename.rs:117:9
    |
 LL | #![warn(clippy::invalid_ref)]
    |         ^^^^^^^^^^^^^^^^^^^ help: use the new name: `invalid_value`
 
 error: lint `clippy::invalid_utf8_in_unchecked` has been renamed to `invalid_from_utf8_unchecked`
-  --> tests/ui/rename.rs:116:9
+  --> tests/ui/rename.rs:118:9
    |
 LL | #![warn(clippy::invalid_utf8_in_unchecked)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `invalid_from_utf8_unchecked`
 
 error: lint `clippy::let_underscore_drop` has been renamed to `let_underscore_drop`
-  --> tests/ui/rename.rs:117:9
+  --> tests/ui/rename.rs:119:9
    |
 LL | #![warn(clippy::let_underscore_drop)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `let_underscore_drop`
 
 error: lint `clippy::maybe_misused_cfg` has been renamed to `unexpected_cfgs`
-  --> tests/ui/rename.rs:118:9
+  --> tests/ui/rename.rs:120:9
    |
 LL | #![warn(clippy::maybe_misused_cfg)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `unexpected_cfgs`
 
 error: lint `clippy::mem_discriminant_non_enum` has been renamed to `enum_intrinsics_non_enums`
-  --> tests/ui/rename.rs:119:9
+  --> tests/ui/rename.rs:121:9
    |
 LL | #![warn(clippy::mem_discriminant_non_enum)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `enum_intrinsics_non_enums`
 
 error: lint `clippy::mismatched_target_os` has been renamed to `unexpected_cfgs`
-  --> tests/ui/rename.rs:120:9
+  --> tests/ui/rename.rs:122:9
    |
 LL | #![warn(clippy::mismatched_target_os)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `unexpected_cfgs`
 
 error: lint `clippy::panic_params` has been renamed to `non_fmt_panics`
-  --> tests/ui/rename.rs:121:9
+  --> tests/ui/rename.rs:123:9
    |
 LL | #![warn(clippy::panic_params)]
    |         ^^^^^^^^^^^^^^^^^^^^ help: use the new name: `non_fmt_panics`
 
 error: lint `clippy::positional_named_format_parameters` has been renamed to `named_arguments_used_positionally`
-  --> tests/ui/rename.rs:122:9
+  --> tests/ui/rename.rs:124:9
    |
 LL | #![warn(clippy::positional_named_format_parameters)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `named_arguments_used_positionally`
 
 error: lint `clippy::temporary_cstring_as_ptr` has been renamed to `dangling_pointers_from_temporaries`
-  --> tests/ui/rename.rs:123:9
+  --> tests/ui/rename.rs:125:9
    |
 LL | #![warn(clippy::temporary_cstring_as_ptr)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `dangling_pointers_from_temporaries`
 
 error: lint `clippy::undropped_manually_drops` has been renamed to `undropped_manually_drops`
-  --> tests/ui/rename.rs:124:9
+  --> tests/ui/rename.rs:126:9
    |
 LL | #![warn(clippy::undropped_manually_drops)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `undropped_manually_drops`
 
 error: lint `clippy::unknown_clippy_lints` has been renamed to `unknown_lints`
-  --> tests/ui/rename.rs:125:9
+  --> tests/ui/rename.rs:127:9
    |
 LL | #![warn(clippy::unknown_clippy_lints)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `unknown_lints`
 
 error: lint `clippy::unused_label` has been renamed to `unused_labels`
-  --> tests/ui/rename.rs:126:9
+  --> tests/ui/rename.rs:128:9
    |
 LL | #![warn(clippy::unused_label)]
    |         ^^^^^^^^^^^^^^^^^^^^ help: use the new name: `unused_labels`
 
 error: lint `clippy::vtable_address_comparisons` has been renamed to `ambiguous_wide_pointer_comparisons`
-  --> tests/ui/rename.rs:127:9
+  --> tests/ui/rename.rs:129:9
    |
 LL | #![warn(clippy::vtable_address_comparisons)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `ambiguous_wide_pointer_comparisons`
 
 error: lint `clippy::reverse_range_loop` has been renamed to `clippy::reversed_empty_ranges`
-  --> tests/ui/rename.rs:128:9
+  --> tests/ui/rename.rs:130:9
    |
 LL | #![warn(clippy::reverse_range_loop)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the new name: `clippy::reversed_empty_ranges`
 
-error: aborting due to 66 previous errors
+error: aborting due to 67 previous errors
 

src/tools/compiletest/src/compute_diff.rs

@@ -144,7 +144,7 @@ where
     }
 
     if !wrote_data {
-        eprintln!("note: diff is identical to nightly rustdoc");
+        println!("note: diff is identical to nightly rustdoc");
         assert!(diff_output.metadata().unwrap().len() == 0);
         return false;
     } else if verbose {

src/tools/compiletest/src/debuggers.rs

@@ -20,7 +20,7 @@ pub(crate) fn configure_gdb(config: &Config) -> Option<Arc<Config>> {
     }
 
     if config.remote_test_client.is_some() && !config.target.contains("android") {
-        eprintln!(
+        println!(
             "WARNING: debuginfo tests are not available when \
              testing with remote"
         );
@@ -28,7 +28,7 @@ pub(crate) fn configure_gdb(config: &Config) -> Option<Arc<Config>> {
     }
 
     if config.target.contains("android") {
-        eprintln!(
+        println!(
             "{} debug-info test uses tcp 5039 port.\
              please reserve it",
             config.target
@@ -50,7 +50,7 @@ pub(crate) fn configure_lldb(config: &Config) -> Option<Arc<Config>> {
     config.lldb_python_dir.as_ref()?;
 
     if let Some(350) = config.lldb_version {
-        eprintln!(
+        println!(
             "WARNING: The used version of LLDB (350) has a \
              known issue that breaks debuginfo tests. See \
              issue #32520 for more information. Skipping all \

src/tools/compiletest/src/lib.rs

@@ -188,8 +188,8 @@ pub fn parse_config(args: Vec<String>) -> Config {
     let (argv0, args_) = args.split_first().unwrap();
     if args.len() == 1 || args[1] == "-h" || args[1] == "--help" {
         let message = format!("Usage: {} [OPTIONS] [TESTNAME...]", argv0);
-        eprintln!("{}", opts.usage(&message));
-        eprintln!();
+        println!("{}", opts.usage(&message));
+        println!();
         panic!()
     }
 
@@ -200,8 +200,8 @@ pub fn parse_config(args: Vec<String>) -> Config {
 
     if matches.opt_present("h") || matches.opt_present("help") {
         let message = format!("Usage: {} [OPTIONS]  [TESTNAME...]", argv0);
-        eprintln!("{}", opts.usage(&message));
-        eprintln!();
+        println!("{}", opts.usage(&message));
+        println!();
         panic!()
     }
 
@@ -501,7 +501,7 @@ pub fn run_tests(config: Arc<Config>) {
             // easy to miss which tests failed, and as such fail to reproduce
             // the failure locally.
 
-            eprintln!(
+            println!(
                 "Some tests failed in compiletest suite={}{} mode={} host={} target={}",
                 config.suite,
                 config

src/tools/compiletest/src/runtest.rs

@@ -774,20 +774,20 @@ impl<'test> TestCx<'test> {
                 unexpected.len(),
                 not_found.len()
             ));
-            eprintln!("status: {}\ncommand: {}\n", proc_res.status, proc_res.cmdline);
+            println!("status: {}\ncommand: {}\n", proc_res.status, proc_res.cmdline);
             if !unexpected.is_empty() {
-                eprintln!("{}", "--- unexpected errors (from JSON output) ---".green());
+                println!("{}", "--- unexpected errors (from JSON output) ---".green());
                 for error in &unexpected {
-                    eprintln!("{}", error.render_for_expected());
+                    println!("{}", error.render_for_expected());
                 }
-                eprintln!("{}", "---".green());
+                println!("{}", "---".green());
             }
             if !not_found.is_empty() {
-                eprintln!("{}", "--- not found errors (from test file) ---".red());
+                println!("{}", "--- not found errors (from test file) ---".red());
                 for error in &not_found {
-                    eprintln!("{}", error.render_for_expected());
+                    println!("{}", error.render_for_expected());
                 }
-                eprintln!("{}", "---\n".red());
+                println!("{}", "---\n".red());
             }
             panic!("errors differ from expected");
         }
@@ -1876,18 +1876,18 @@ impl<'test> TestCx<'test> {
 
     fn maybe_dump_to_stdout(&self, out: &str, err: &str) {
         if self.config.verbose {
-            eprintln!("------stdout------------------------------");
-            eprintln!("{}", out);
-            eprintln!("------stderr------------------------------");
-            eprintln!("{}", err);
-            eprintln!("------------------------------------------");
+            println!("------stdout------------------------------");
+            println!("{}", out);
+            println!("------stderr------------------------------");
+            println!("{}", err);
+            println!("------------------------------------------");
         }
     }
 
     fn error(&self, err: &str) {
         match self.revision {
-            Some(rev) => eprintln!("\nerror in revision `{}`: {}", rev, err),
-            None => eprintln!("\nerror: {}", err),
+            Some(rev) => println!("\nerror in revision `{}`: {}", rev, err),
+            None => println!("\nerror: {}", err),
         }
     }
 
@@ -1972,7 +1972,7 @@ impl<'test> TestCx<'test> {
         if !self.config.has_html_tidy {
             return;
         }
-        eprintln!("info: generating a diff against nightly rustdoc");
+        println!("info: generating a diff against nightly rustdoc");
 
         let suffix =
             self.safe_revision().map_or("nightly".into(), |path| path.to_owned() + "-nightly");
@@ -2082,7 +2082,7 @@ impl<'test> TestCx<'test> {
                 .output()
                 .unwrap();
             assert!(output.status.success());
-            eprintln!("{}", String::from_utf8_lossy(&output.stdout));
+            println!("{}", String::from_utf8_lossy(&output.stdout));
             eprintln!("{}", String::from_utf8_lossy(&output.stderr));
         } else {
             use colored::Colorize;
@@ -2482,7 +2482,7 @@ impl<'test> TestCx<'test> {
                 )"#
             )
             .replace_all(&output, |caps: &Captures<'_>| {
-                eprintln!("{}", &caps[0]);
+                println!("{}", &caps[0]);
                 caps[0].replace(r"\", "/")
             })
             .replace("\r\n", "\n")
@@ -2581,16 +2581,16 @@ impl<'test> TestCx<'test> {
         if let Err(err) = fs::write(&actual_path, &actual) {
             self.fatal(&format!("failed to write {stream} to `{actual_path:?}`: {err}",));
         }
-        eprintln!("Saved the actual {stream} to {actual_path:?}");
+        println!("Saved the actual {stream} to {actual_path:?}");
 
         let expected_path =
             expected_output_path(self.testpaths, self.revision, &self.config.compare_mode, stream);
 
         if !self.config.bless {
             if expected.is_empty() {
-                eprintln!("normalized {}:\n{}\n", stream, actual);
+                println!("normalized {}:\n{}\n", stream, actual);
             } else {
-                eprintln!("diff of {stream}:\n");
+                println!("diff of {stream}:\n");
                 if let Some(diff_command) = self.config.diff_command.as_deref() {
                     let mut args = diff_command.split_whitespace();
                     let name = args.next().unwrap();
@@ -2625,10 +2625,10 @@ impl<'test> TestCx<'test> {
             if let Err(err) = fs::write(&expected_path, &actual) {
                 self.fatal(&format!("failed to write {stream} to `{expected_path:?}`: {err}"));
             }
-            eprintln!("Blessing the {stream} of {test_name} in {expected_path:?}");
+            println!("Blessing the {stream} of {test_name} in {expected_path:?}");
         }
 
-        eprintln!("\nThe actual {0} differed from the expected {0}.", stream);
+        println!("\nThe actual {0} differed from the expected {0}.", stream);
 
         if self.config.bless { 0 } else { 1 }
     }
@@ -2707,7 +2707,7 @@ impl<'test> TestCx<'test> {
         fs::create_dir_all(&incremental_dir).unwrap();
 
         if self.config.verbose {
-            eprintln!("init_incremental_test: incremental_dir={}", incremental_dir.display());
+            println!("init_incremental_test: incremental_dir={}", incremental_dir.display());
         }
     }
 
@@ -2765,7 +2765,7 @@ impl ProcRes {
             }
         }
 
-        eprintln!(
+        println!(
             "status: {}\ncommand: {}\n{}\n{}\n",
             self.status,
             self.cmdline,
@@ -2776,7 +2776,7 @@ impl ProcRes {
 
     pub fn fatal(&self, err: Option<&str>, on_failure: impl FnOnce()) -> ! {
         if let Some(e) = err {
-            eprintln!("\nerror: {}", e);
+            println!("\nerror: {}", e);
         }
         self.print_info();
         on_failure();

src/tools/compiletest/src/runtest/codegen_units.rs

@@ -64,13 +64,13 @@ impl TestCx<'_> {
         if !missing.is_empty() {
             missing.sort();
 
-            eprintln!("\nThese items should have been contained but were not:\n");
+            println!("\nThese items should have been contained but were not:\n");
 
             for item in &missing {
-                eprintln!("{}", item);
+                println!("{}", item);
             }
 
-            eprintln!("\n");
+            println!("\n");
         }
 
         if !unexpected.is_empty() {
@@ -80,24 +80,24 @@ impl TestCx<'_> {
                 sorted
             };
 
-            eprintln!("\nThese items were contained but should not have been:\n");
+            println!("\nThese items were contained but should not have been:\n");
 
             for item in sorted {
-                eprintln!("{}", item);
+                println!("{}", item);
             }
 
-            eprintln!("\n");
+            println!("\n");
         }
 
         if !wrong_cgus.is_empty() {
             wrong_cgus.sort_by_key(|pair| pair.0.name.clone());
-            eprintln!("\nThe following items were assigned to wrong codegen units:\n");
+            println!("\nThe following items were assigned to wrong codegen units:\n");
 
             for &(ref expected_item, ref actual_item) in &wrong_cgus {
-                eprintln!("{}", expected_item.name);
-                eprintln!("  expected: {}", codegen_units_to_str(&expected_item.codegen_units));
-                eprintln!("  actual:   {}", codegen_units_to_str(&actual_item.codegen_units));
-                eprintln!();
+                println!("{}", expected_item.name);
+                println!("  expected: {}", codegen_units_to_str(&expected_item.codegen_units));
+                println!("  actual:   {}", codegen_units_to_str(&actual_item.codegen_units));
+                println!();
             }
         }
 

src/tools/compiletest/src/runtest/debuginfo.rs

@@ -260,7 +260,7 @@ impl TestCx<'_> {
                 cmdline,
             };
             if adb.kill().is_err() {
-                eprintln!("Adb process is already finished.");
+                println!("Adb process is already finished.");
             }
         } else {
             let rust_src_root =
@@ -275,7 +275,7 @@ impl TestCx<'_> {
 
             match self.config.gdb_version {
                 Some(version) => {
-                    eprintln!("NOTE: compiletest thinks it is using GDB version {}", version);
+                    println!("NOTE: compiletest thinks it is using GDB version {}", version);
 
                     if version > extract_gdb_version("7.4").unwrap() {
                         // Add the directory containing the pretty printers to
@@ -297,7 +297,7 @@ impl TestCx<'_> {
                     }
                 }
                 _ => {
-                    eprintln!(
+                    println!(
                         "NOTE: compiletest does not know which version of \
                          GDB it is using"
                     );
@@ -392,10 +392,10 @@ impl TestCx<'_> {
 
         match self.config.lldb_version {
             Some(ref version) => {
-                eprintln!("NOTE: compiletest thinks it is using LLDB version {}", version);
+                println!("NOTE: compiletest thinks it is using LLDB version {}", version);
             }
             _ => {
-                eprintln!(
+                println!(
                     "NOTE: compiletest does not know which version of \
                      LLDB it is using"
                 );

src/tools/compiletest/src/runtest/rustdoc_json.rs

@@ -29,7 +29,7 @@ impl TestCx<'_> {
 
         if !res.status.success() {
             self.fatal_proc_rec_with_ctx("jsondocck failed!", &res, |_| {
-                eprintln!("Rustdoc Output:");
+                println!("Rustdoc Output:");
                 proc_res.print_info();
             })
         }

src/tools/compiletest/src/runtest/ui.rs

@@ -109,10 +109,10 @@ impl TestCx<'_> {
         }
 
         if errors > 0 {
-            eprintln!("To update references, rerun the tests and pass the `--bless` flag");
+            println!("To update references, rerun the tests and pass the `--bless` flag");
             let relative_path_to_file =
                 self.testpaths.relative_dir.join(self.testpaths.file.file_name().unwrap());
-            eprintln!(
+            println!(
                 "To only update this specific test, also pass `--test-args {}`",
                 relative_path_to_file.display(),
             );

src/tools/compiletest/src/util.rs

@@ -30,7 +30,7 @@ fn path_div() -> &'static str {
 pub fn logv(config: &Config, s: String) {
     debug!("{}", s);
     if config.verbose {
-        eprintln!("{}", s);
+        println!("{}", s);
     }
 }
 

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

@@ -1,3 +1,5 @@
+#![allow(unpredictable_function_pointer_comparisons)]
+
 use std::mem;
 
 trait Answer {

src/tools/miri/tests/pass/issues/issue-91636.rs

@@ -1,3 +1,5 @@
+#![allow(unpredictable_function_pointer_comparisons)]
+
 type BuiltIn = for<'a> fn(&str);
 
 struct Function {

src/tools/rust-analyzer/crates/ide-db/src/generated/lints.rs

@@ -3936,17 +3936,8 @@ The tracking issue for this feature is: [#117693]
 "##,
     },
     Lint {
-        label: "core_pattern_type",
-        description: r##"# `core_pattern_type`
-
-This feature has no tracking issue, and is therefore likely internal to the compiler, not being intended for general use.
-
-------------------------
-"##,
-    },
-    Lint {
-        label: "core_pattern_types",
-        description: r##"# `core_pattern_types`
+        label: "pattern_type_macro",
+        description: r##"# `pattern_type_macro`
 
 This feature has no tracking issue, and is therefore likely internal to the compiler, not being intended for general use.
 

src/tools/tidy/src/error_codes.rs

@@ -38,7 +38,7 @@ const IGNORE_UI_TEST_CHECK: &[&str] =
 macro_rules! verbose_print {
     ($verbose:expr, $($fmt:tt)*) => {
         if $verbose {
-            eprintln!("{}", format_args!($($fmt)*));
+            println!("{}", format_args!($($fmt)*));
         }
     };
 }
@@ -49,8 +49,8 @@ pub fn check(root_path: &Path, search_paths: &[&Path], verbose: bool, bad: &mut
     // Stage 1: create list
     let error_codes = extract_error_codes(root_path, &mut errors);
     if verbose {
-        eprintln!("Found {} error codes", error_codes.len());
-        eprintln!("Highest error code: `{}`", error_codes.iter().max().unwrap());
+        println!("Found {} error codes", error_codes.len());
+        println!("Highest error code: `{}`", error_codes.iter().max().unwrap());
     }
 
     // Stage 2: check list has docs

src/tools/tidy/src/features.rs

@@ -158,14 +158,14 @@ pub fn check(
         .collect::<Vec<_>>();
 
     for &(name, _) in gate_untested.iter() {
-        eprintln!("Expected a gate test for the feature '{name}'.");
-        eprintln!(
+        println!("Expected a gate test for the feature '{name}'.");
+        println!(
             "Hint: create a failing test file named 'tests/ui/feature-gates/feature-gate-{}.rs',\
                 \n      with its failures due to missing usage of `#![feature({})]`.",
             name.replace("_", "-"),
             name
         );
-        eprintln!(
+        println!(
             "Hint: If you already have such a test and don't want to rename it,\
                 \n      you can also add a // gate-test-{} line to the test file.",
             name
@@ -218,7 +218,7 @@ pub fn check(
 
         lines.sort();
         for line in lines {
-            eprintln!("* {line}");
+            println!("* {line}");
         }
     }
 

src/tools/tidy/src/fluent_period.rs

@@ -18,7 +18,6 @@ const ALLOWLIST: &[&str] = &[
     "const_eval_validation_failure_note",
     "driver_impl_ice",
     "incremental_corrupt_file",
-    "mir_build_pointer_pattern",
 ];
 
 fn check_period(filename: &str, contents: &str, bad: &mut bool) {

src/tools/tidy/src/unstable_book.rs

@@ -118,16 +118,16 @@ pub fn check(path: &Path, features: CollectedFeatures, bad: &mut bool) {
     // List unstable features that don't have Unstable Book sections.
     // Remove the comment marker if you want the list printed.
     /*
-    eprintln!("Lib features without unstable book sections:");
+    println!("Lib features without unstable book sections:");
     for feature_name in &unstable_lang_feature_names -
                         &unstable_book_lang_features_section_file_names {
-        eprintln!("    * {} {:?}", feature_name, lib_features[&feature_name].tracking_issue);
+        println!("    * {} {:?}", feature_name, lib_features[&feature_name].tracking_issue);
     }
 
-    eprintln!("Lang features without unstable book sections:");
+    println!("Lang features without unstable book sections:");
     for feature_name in &unstable_lib_feature_names-
                         &unstable_book_lib_features_section_file_names {
-        eprintln!("    * {} {:?}", feature_name, lang_features[&feature_name].tracking_issue);
+        println!("    * {} {:?}", feature_name, lang_features[&feature_name].tracking_issue);
     }
     // */
 }

src/tools/tidy/src/x_version.rs

@@ -42,7 +42,7 @@ pub fn check(root: &Path, cargo: &Path, bad: &mut bool) {
 
         if let Some(expected) = get_x_wrapper_version(root, cargo) {
             if installed < expected {
-                return eprintln!(
+                return println!(
                     "Current version of x is {installed}, but the latest version is {expected}\nConsider updating to the newer version of x by running `cargo install --path src/tools/x`"
                 );
             }

tests/codegen/pattern_type_symbols.rs

@@ -4,8 +4,7 @@
 //@ compile-flags: -Csymbol-mangling-version=v0 -Copt-level=0 --crate-type=lib
 
 #![feature(pattern_types)]
-#![feature(core_pattern_types)]
-#![feature(core_pattern_type)]
+#![feature(pattern_type_macro)]
 
 use std::pat::pattern_type;
 

tests/ui/associated-consts/associated-const-type-parameter-pattern.rs

@@ -18,17 +18,17 @@ impl Foo for Def {
 pub fn test<A: Foo, B: Foo>(arg: EFoo) {
     match arg {
         A::X => println!("A::X"),
-        //~^ error: constant pattern depends on a generic parameter
+        //~^ ERROR constant pattern cannot depend on generic parameters
         B::X => println!("B::X"),
-        //~^ error: constant pattern depends on a generic parameter
+        //~^ ERROR constant pattern cannot depend on generic parameters
         _ => (),
     }
 }
 
 pub fn test_let_pat<A: Foo, B: Foo>(arg: EFoo, A::X: EFoo) {
-    //~^ ERROR constant pattern depends on a generic parameter
+    //~^ ERROR constant pattern cannot depend on generic parameters
     let A::X = arg;
-    //~^ ERROR constant pattern depends on a generic parameter
+    //~^ ERROR constant pattern cannot depend on generic parameters
 }
 
 fn main() {

tests/ui/associated-consts/associated-const-type-parameter-pattern.stderr

@@ -1,26 +1,57 @@
-error[E0158]: constant pattern depends on a generic parameter
+error[E0158]: constant pattern cannot depend on generic parameters
   --> $DIR/associated-const-type-parameter-pattern.rs:20:9
    |
+LL | pub trait Foo {
+   | -------------
+LL |     const X: EFoo;
+   |     ------------- constant defined here
+...
+LL | pub fn test<A: Foo, B: Foo>(arg: EFoo) {
+   |             - constant depends on this generic parameter
+LL |     match arg {
 LL |         A::X => println!("A::X"),
-   |         ^^^^
+   |         ^^^^ `const` depends on a generic parameter
 
-error[E0158]: constant pattern depends on a generic parameter
+error[E0158]: constant pattern cannot depend on generic parameters
   --> $DIR/associated-const-type-parameter-pattern.rs:22:9
    |
+LL | pub trait Foo {
+   | -------------
+LL |     const X: EFoo;
+   |     ------------- constant defined here
+...
+LL | pub fn test<A: Foo, B: Foo>(arg: EFoo) {
+   |                     - constant depends on this generic parameter
+...
 LL |         B::X => println!("B::X"),
-   |         ^^^^
+   |         ^^^^ `const` depends on a generic parameter
 
-error[E0158]: constant pattern depends on a generic parameter
+error[E0158]: constant pattern cannot depend on generic parameters
   --> $DIR/associated-const-type-parameter-pattern.rs:30:9
    |
+LL | pub trait Foo {
+   | -------------
+LL |     const X: EFoo;
+   |     ------------- constant defined here
+...
+LL | pub fn test_let_pat<A: Foo, B: Foo>(arg: EFoo, A::X: EFoo) {
+   |                     - constant depends on this generic parameter
+LL |
 LL |     let A::X = arg;
-   |         ^^^^
+   |         ^^^^ `const` depends on a generic parameter
 
-error[E0158]: constant pattern depends on a generic parameter
+error[E0158]: constant pattern cannot depend on generic parameters
   --> $DIR/associated-const-type-parameter-pattern.rs:28:48
    |
+LL | pub trait Foo {
+   | -------------
+LL |     const X: EFoo;
+   |     ------------- constant defined here
+...
 LL | pub fn test_let_pat<A: Foo, B: Foo>(arg: EFoo, A::X: EFoo) {
-   |                                                ^^^^
+   |                     -                          ^^^^ `const` depends on a generic parameter
+   |                     |
+   |                     constant depends on this generic parameter
 
 error: aborting due to 4 previous errors
 

tests/ui/binding/const-param.rs

@@ -2,7 +2,7 @@
 
 fn check<const N: usize>() {
     match 1 {
-        N => {} //~ ERROR const parameters cannot be referenced in patterns
+        N => {} //~ ERROR constant parameters cannot be referenced in patterns
         _ => {}
     }
 }

tests/ui/binding/const-param.stderr

@@ -1,8 +1,11 @@
-error[E0158]: const parameters cannot be referenced in patterns
+error[E0158]: constant parameters cannot be referenced in patterns
   --> $DIR/const-param.rs:5:9
    |
+LL | fn check<const N: usize>() {
+   |          -------------- constant defined here
+LL |     match 1 {
 LL |         N => {}
-   |         ^
+   |         ^ can't be used in patterns
 
 error: aborting due to 1 previous error
 

tests/ui/binop/binary-op-on-fn-ptr-eq.rs

@@ -1,6 +1,9 @@
 //@ run-pass
 // Tests equality between supertype and subtype of a function
 // See the issue #91636
+
+#![allow(unpredictable_function_pointer_comparisons)]
+
 fn foo(_a: &str) {}
 
 fn main() {

tests/ui/box/unit/unique-ffi-symbols.rs

@@ -1,6 +1,9 @@
 //@ run-pass
 // We used to have a __rust_abi shim that resulted in duplicated symbols
 // whenever the item path wasn't enough to disambiguate between them.
+
+#![allow(unpredictable_function_pointer_comparisons)]
+
 fn main() {
     let a = {
         extern "C" fn good() -> i32 { return 0; }

tests/ui/const_prop/ice-type-mismatch-when-copying-112824.rs

@@ -12,8 +12,7 @@ impl Opcode2 {
 
 pub fn example2(msg_type: Opcode2) -> impl FnMut(&[u8]) {
     move |i| match msg_type {
-        Opcode2::OP2 => unimplemented!(),
-        //~^ ERROR: could not evaluate constant pattern
+        Opcode2::OP2 => unimplemented!(), // ok, `const` already emitted an error
     }
 }
 

tests/ui/const_prop/ice-type-mismatch-when-copying-112824.stderr

@@ -17,13 +17,7 @@ help: you might be missing a type parameter
 LL | pub struct Opcode2<S>(&'a S);
    |                   +++
 
-error: could not evaluate constant pattern
-  --> $DIR/ice-type-mismatch-when-copying-112824.rs:15:9
-   |
-LL |         Opcode2::OP2 => unimplemented!(),
-   |         ^^^^^^^^^^^^
-
-error: aborting due to 3 previous errors
+error: aborting due to 2 previous errors
 
 Some errors have detailed explanations: E0261, E0412.
 For more information about an error, try `rustc --explain E0261`.

tests/ui/consts/const-eval/const-eval-overflow-2.rs

@@ -12,8 +12,7 @@ const NEG_NEG_128: i8 = -NEG_128; //~ ERROR constant
 
 fn main() {
     match -128i8 {
-        NEG_NEG_128 => println!("A"),
-        //~^ ERROR could not evaluate constant pattern
+        NEG_NEG_128 => println!("A"), // ok, `const` error already emitted
         _ => println!("B"),
     }
 }

tests/ui/consts/const-eval/const-eval-overflow-2.stderr

@@ -4,12 +4,6 @@ error[E0080]: evaluation of constant value failed
 LL | const NEG_NEG_128: i8 = -NEG_128;
    |                         ^^^^^^^^ attempt to negate `i8::MIN`, which would overflow
 
-error: could not evaluate constant pattern
-  --> $DIR/const-eval-overflow-2.rs:15:9
-   |
-LL |         NEG_NEG_128 => println!("A"),
-   |         ^^^^^^^^^^^
-
-error: aborting due to 2 previous errors
+error: aborting due to 1 previous error
 
 For more information about this error, try `rustc --explain E0080`.

tests/ui/consts/const-eval/ref_to_int_match.32bit.stderr

@@ -7,12 +7,6 @@ LL | const BAR: Int = unsafe { Foo { r: &42 }.f };
    = help: this code performed an operation that depends on the underlying bytes representing a pointer
    = help: the absolute address of a pointer is not known at compile-time, so such operations are not supported
 
-error: could not evaluate constant pattern
-  --> $DIR/ref_to_int_match.rs:7:14
-   |
-LL |         10..=BAR => {},
-   |              ^^^
-
-error: aborting due to 2 previous errors
+error: aborting due to 1 previous error
 
 For more information about this error, try `rustc --explain E0080`.

tests/ui/consts/const-eval/ref_to_int_match.64bit.stderr

@@ -7,12 +7,6 @@ LL | const BAR: Int = unsafe { Foo { r: &42 }.f };
    = help: this code performed an operation that depends on the underlying bytes representing a pointer
    = help: the absolute address of a pointer is not known at compile-time, so such operations are not supported
 
-error: could not evaluate constant pattern
-  --> $DIR/ref_to_int_match.rs:7:14
-   |
-LL |         10..=BAR => {},
-   |              ^^^
-
-error: aborting due to 2 previous errors
+error: aborting due to 1 previous error
 
 For more information about this error, try `rustc --explain E0080`.

tests/ui/consts/const-eval/ref_to_int_match.rs

@@ -4,7 +4,7 @@ fn main() {
     let n: Int = 40;
     match n {
         0..=10 => {},
-        10..=BAR => {}, //~ ERROR could not evaluate constant pattern
+        10..=BAR => {}, // ok, `const` error already emitted
         _ => {},
     }
 }

tests/ui/consts/const-extern-function.rs

@@ -1,5 +1,7 @@
 //@ run-pass
+
 #![allow(non_upper_case_globals)]
+#![allow(unpredictable_function_pointer_comparisons)]
 
 extern "C" fn foopy() {}
 

tests/ui/consts/const_in_pattern/cross-crate-fail.rs

@@ -9,15 +9,13 @@ fn main() {
     let _ = Defaulted;
     match None {
         consts::SOME => panic!(),
-        //~^ must be annotated with `#[derive(PartialEq)]`
-
+        //~^ ERROR constant of non-structural type `CustomEq` in a pattern
         _ => {}
     }
 
     match None {
         <Defaulted as consts::AssocConst>::SOME  => panic!(),
-        //~^ must be annotated with `#[derive(PartialEq)]`
-
+        //~^ ERROR constant of non-structural type `CustomEq` in a pattern
         _ => {}
     }
 }

tests/ui/consts/const_in_pattern/cross-crate-fail.stderr

@@ -1,19 +1,33 @@
-error: to use a constant of type `CustomEq` in a pattern, `CustomEq` must be annotated with `#[derive(PartialEq)]`
+error: constant of non-structural type `CustomEq` in a pattern
   --> $DIR/cross-crate-fail.rs:11:9
    |
 LL |         consts::SOME => panic!(),
-   |         ^^^^^^^^^^^^
+   |         ^^^^^^^^^^^^ constant of non-structural type
+   |
+  ::: $DIR/auxiliary/consts.rs:1:1
+   |
+LL | pub struct CustomEq;
+   | ------------------- `CustomEq` must be annotated with `#[derive(PartialEq)]` to be usable in patterns
+...
+LL | pub const SOME: Option<CustomEq> = Some(CustomEq);
+   | -------------------------------- constant defined here
    |
-   = note: the traits must be derived, manual `impl`s are not sufficient
    = note: see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
 
-error: to use a constant of type `CustomEq` in a pattern, `CustomEq` must be annotated with `#[derive(PartialEq)]`
-  --> $DIR/cross-crate-fail.rs:18:9
+error: constant of non-structural type `CustomEq` in a pattern
+  --> $DIR/cross-crate-fail.rs:17:9
    |
 LL |         <Defaulted as consts::AssocConst>::SOME  => panic!(),
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ constant of non-structural type
+   |
+  ::: $DIR/auxiliary/consts.rs:1:1
+   |
+LL | pub struct CustomEq;
+   | ------------------- `CustomEq` must be annotated with `#[derive(PartialEq)]` to be usable in patterns
+...
+LL |     const SOME: Option<CustomEq> = Some(CustomEq);
+   |     ---------------------------- constant defined here
    |
-   = note: the traits must be derived, manual `impl`s are not sufficient
    = note: see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
 
 error: aborting due to 2 previous errors

tests/ui/consts/const_in_pattern/issue-34784-match-on-non-int-raw-ptr.stderr

@@ -1,26 +1,46 @@
-error: function pointers and raw pointers not derived from integers in patterns behave unpredictably and should not be relied upon. See https://github.com/rust-lang/rust/issues/70861 for details.
+error: function pointers and raw pointers not derived from integers in patterns behave unpredictably and should not be relied upon
   --> $DIR/issue-34784-match-on-non-int-raw-ptr.rs:9:9
    |
+LL | const C: *const u8 = &0;
+   | ------------------ constant defined here
+...
 LL |         C => {}
-   |         ^
+   |         ^ can't be used in patterns
+   |
+   = note: see https://github.com/rust-lang/rust/issues/70861 for details
 
-error: function pointers and raw pointers not derived from integers in patterns behave unpredictably and should not be relied upon. See https://github.com/rust-lang/rust/issues/70861 for details.
+error: function pointers and raw pointers not derived from integers in patterns behave unpredictably and should not be relied upon
   --> $DIR/issue-34784-match-on-non-int-raw-ptr.rs:16:9
    |
+LL | const C_INNER: (*const u8, u8) = (C, 0);
+   | ------------------------------ constant defined here
+...
 LL |         C_INNER => {}
-   |         ^^^^^^^
+   |         ^^^^^^^ can't be used in patterns
+   |
+   = note: see https://github.com/rust-lang/rust/issues/70861 for details
 
-error: function pointers and raw pointers not derived from integers in patterns behave unpredictably and should not be relied upon. See https://github.com/rust-lang/rust/issues/70861 for details.
+error: function pointers and raw pointers not derived from integers in patterns behave unpredictably and should not be relied upon
   --> $DIR/issue-34784-match-on-non-int-raw-ptr.rs:27:9
    |
+LL | const D: *const [u8; 4] = b"abcd";
+   | ----------------------- constant defined here
+...
 LL |         D => {}
-   |         ^
+   |         ^ can't be used in patterns
+   |
+   = note: see https://github.com/rust-lang/rust/issues/70861 for details
 
-error: function pointers and raw pointers not derived from integers in patterns behave unpredictably and should not be relied upon. See https://github.com/rust-lang/rust/issues/70861 for details.
+error: function pointers and raw pointers not derived from integers in patterns behave unpredictably and should not be relied upon
   --> $DIR/issue-34784-match-on-non-int-raw-ptr.rs:32:9
    |
+LL | const STR: *const str = "abcd";
+   | --------------------- constant defined here
+...
 LL |         STR => {}
-   |         ^^^
+   |         ^^^ can't be used in patterns
+   |
+   = note: see https://github.com/rust-lang/rust/issues/70861 for details
 
 error: aborting due to 4 previous errors
 

tests/ui/consts/const_in_pattern/issue-44333.stderr

@@ -1,14 +1,24 @@
-error: function pointers and raw pointers not derived from integers in patterns behave unpredictably and should not be relied upon. See https://github.com/rust-lang/rust/issues/70861 for details.
+error: function pointers and raw pointers not derived from integers in patterns behave unpredictably and should not be relied upon
   --> $DIR/issue-44333.rs:15:9
    |
+LL | const FOO: Func = foo;
+   | --------------- constant defined here
+...
 LL |         FOO => println!("foo"),
-   |         ^^^
+   |         ^^^ can't be used in patterns
+   |
+   = note: see https://github.com/rust-lang/rust/issues/70861 for details
 
-error: function pointers and raw pointers not derived from integers in patterns behave unpredictably and should not be relied upon. See https://github.com/rust-lang/rust/issues/70861 for details.
+error: function pointers and raw pointers not derived from integers in patterns behave unpredictably and should not be relied upon
   --> $DIR/issue-44333.rs:16:9
    |
+LL | const BAR: Func = bar;
+   | --------------- constant defined here
+...
 LL |         BAR => println!("bar"),
-   |         ^^^
+   |         ^^^ can't be used in patterns
+   |
+   = note: see https://github.com/rust-lang/rust/issues/70861 for details
 
 error: aborting due to 2 previous errors
 

tests/ui/consts/const_in_pattern/issue-65466.rs

@@ -11,7 +11,7 @@ const C: &[O<B>] = &[O::None];
 fn main() {
     let x = O::None;
     match &[x][..] {
-        C => (), //~ERROR: the type must implement `PartialEq`
+        C => (), //~ ERROR constant of non-structural type `&[O<B>]` in a pattern
         _ => (),
     }
 }

tests/ui/consts/const_in_pattern/issue-65466.stderr

@@ -1,8 +1,16 @@
-error: to use a constant of type `&[O<B>]` in a pattern, the type must implement `PartialEq`
+error: constant of non-structural type `&[O<B>]` in a pattern
   --> $DIR/issue-65466.rs:14:9
    |
+LL | struct B;
+   | -------- must be annotated with `#[derive(PartialEq)]` to be usable in patterns
+LL |
+LL | const C: &[O<B>] = &[O::None];
+   | ---------------- constant defined here
+...
 LL |         C => (),
-   |         ^
+   |         ^ constant of non-structural type
+   |
+   = note: see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
 
 error: aborting due to 1 previous error
 

tests/ui/consts/const_in_pattern/no-eq-branch-fail.rs

@@ -16,8 +16,7 @@ const BAR_BAZ: Foo = if 42 == 42 {
 
 fn main() {
     match Foo::Qux(NoEq) {
-        BAR_BAZ => panic!(),
-        //~^ ERROR must be annotated with `#[derive(PartialEq)]`
+        BAR_BAZ => panic!(), //~ ERROR constant of non-structural type `Foo` in a pattern
         _ => {}
     }
 }

tests/ui/consts/const_in_pattern/no-eq-branch-fail.stderr

@@ -1,10 +1,15 @@
-error: to use a constant of type `Foo` in a pattern, `Foo` must be annotated with `#[derive(PartialEq)]`
+error: constant of non-structural type `Foo` in a pattern
   --> $DIR/no-eq-branch-fail.rs:19:9
    |
+LL | enum Foo {
+   | -------- `Foo` must be annotated with `#[derive(PartialEq)]` to be usable in patterns
+...
+LL | const BAR_BAZ: Foo = if 42 == 42 {
+   | ------------------ constant defined here
+...
 LL |         BAR_BAZ => panic!(),
-   |         ^^^^^^^
+   |         ^^^^^^^ constant of non-structural type
    |
-   = note: the traits must be derived, manual `impl`s are not sufficient
    = note: see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
 
 error: aborting due to 1 previous error

tests/ui/consts/const_in_pattern/reject_non_partial_eq.rs

@@ -26,7 +26,7 @@ fn main() {
 
     match None {
         NO_PARTIAL_EQ_NONE => println!("NO_PARTIAL_EQ_NONE"),
-        //~^ ERROR must implement `PartialEq`
+        //~^ ERROR constant of non-structural type `Option<NoPartialEq>` in a pattern
         _ => panic!("whoops"),
     }
 }

tests/ui/consts/const_in_pattern/reject_non_partial_eq.stderr

@@ -1,8 +1,16 @@
-error: to use a constant of type `Option<NoPartialEq>` in a pattern, the type must implement `PartialEq`
+error: constant of non-structural type `Option<NoPartialEq>` in a pattern
   --> $DIR/reject_non_partial_eq.rs:28:9
    |
+LL | struct NoPartialEq(u32);
+   | ------------------ must be annotated with `#[derive(PartialEq)]` to be usable in patterns
+...
+LL | const NO_PARTIAL_EQ_NONE: Option<NoPartialEq> = None;
+   | --------------------------------------------- constant defined here
+...
 LL |         NO_PARTIAL_EQ_NONE => println!("NO_PARTIAL_EQ_NONE"),
-   |         ^^^^^^^^^^^^^^^^^^
+   |         ^^^^^^^^^^^^^^^^^^ constant of non-structural type
+   |
+   = note: see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
 
 error: aborting due to 1 previous error
 

tests/ui/consts/const_in_pattern/reject_non_structural.rs

@@ -17,9 +17,29 @@ struct NoPartialEq;
 
 #[derive(Copy, Clone, Debug)]
 struct NoDerive;
+//~^ NOTE must be annotated with `#[derive(PartialEq)]`
+//~| NOTE must be annotated with `#[derive(PartialEq)]`
+//~| NOTE must be annotated with `#[derive(PartialEq)]`
+//~| NOTE must be annotated with `#[derive(PartialEq)]`
+//~| NOTE must be annotated with `#[derive(PartialEq)]`
+//~| NOTE must be annotated with `#[derive(PartialEq)]`
+//~| NOTE must be annotated with `#[derive(PartialEq)]`
+//~| NOTE must be annotated with `#[derive(PartialEq)]`
+//~| NOTE must be annotated with `#[derive(PartialEq)]`
+//~| NOTE must be annotated with `#[derive(PartialEq)]`
 
 // This impl makes `NoDerive` irreflexive.
 impl PartialEq for NoDerive { fn eq(&self, _: &Self) -> bool { false } }
+//~^ NOTE StructuralPartialEq.html for details
+//~| NOTE StructuralPartialEq.html for details
+//~| NOTE StructuralPartialEq.html for details
+//~| NOTE StructuralPartialEq.html for details
+//~| NOTE StructuralPartialEq.html for details
+//~| NOTE StructuralPartialEq.html for details
+//~| NOTE StructuralPartialEq.html for details
+//~| NOTE StructuralPartialEq.html for details
+//~| NOTE StructuralPartialEq.html for details
+//~| NOTE StructuralPartialEq.html for details
 
 impl Eq for NoDerive { }
 
@@ -36,65 +56,55 @@ fn main() {
     #[derive(PartialEq, Eq, Debug)]
     enum Derive<X> { Some(X), None, }
 
-    const ENUM: Derive<NoDerive> = Derive::Some(NoDerive);
+    const ENUM: Derive<NoDerive> = Derive::Some(NoDerive); //~ NOTE constant defined here
     match Derive::Some(NoDerive) { ENUM => dbg!(ENUM), _ => panic!("whoops"), };
-    //~^ ERROR must be annotated with `#[derive(PartialEq)]`
-    //~| NOTE the traits must be derived
-    //~| NOTE StructuralPartialEq.html for details
+    //~^ ERROR constant of non-structural type `NoDerive` in a pattern
+    //~| NOTE constant of non-structural type
 
-    const FIELD: OND = TrivialEq(Some(NoDerive)).0;
+    const FIELD: OND = TrivialEq(Some(NoDerive)).0; //~ NOTE constant defined here
     match Some(NoDerive) { FIELD => dbg!(FIELD), _ => panic!("whoops"), };
-    //~^ ERROR must be annotated with `#[derive(PartialEq)]`
-    //~| NOTE the traits must be derived
-    //~| NOTE StructuralPartialEq.html for details
+    //~^ ERROR constant of non-structural type `NoDerive` in a pattern
+    //~| NOTE constant of non-structural type
 
     const NO_DERIVE_SOME: OND = Some(NoDerive);
-    const INDIRECT: OND = NO_DERIVE_SOME;
+    const INDIRECT: OND = NO_DERIVE_SOME; //~ NOTE constant defined here
     match Some(NoDerive) {INDIRECT => dbg!(INDIRECT), _ => panic!("whoops"), };
-    //~^ ERROR must be annotated with `#[derive(PartialEq)]`
-    //~| NOTE the traits must be derived
-    //~| NOTE StructuralPartialEq.html for details
+    //~^ ERROR constant of non-structural type `NoDerive` in a pattern
+    //~| NOTE constant of non-structural type
 
-    const TUPLE: (OND, OND) = (None, Some(NoDerive));
+    const TUPLE: (OND, OND) = (None, Some(NoDerive)); //~ NOTE constant defined here
     match (None, Some(NoDerive)) { TUPLE => dbg!(TUPLE), _ => panic!("whoops"), };
-    //~^ ERROR must be annotated with `#[derive(PartialEq)]`
-    //~| NOTE the traits must be derived
-    //~| NOTE StructuralPartialEq.html for details
+    //~^ ERROR constant of non-structural type `NoDerive` in a pattern
+    //~| NOTE constant of non-structural type
 
-    const TYPE_ASCRIPTION: OND = type_ascribe!(Some(NoDerive), OND);
+    const TYPE_ASCRIPTION: OND = type_ascribe!(Some(NoDerive), OND); //~ NOTE constant defined here
     match Some(NoDerive) { TYPE_ASCRIPTION => dbg!(TYPE_ASCRIPTION), _ => panic!("whoops"), };
-    //~^ ERROR must be annotated with `#[derive(PartialEq)]`
-    //~| NOTE the traits must be derived
-    //~| NOTE StructuralPartialEq.html for details
+    //~^ ERROR constant of non-structural type `NoDerive` in a pattern
+    //~| NOTE constant of non-structural type
 
-    const ARRAY: [OND; 2] = [None, Some(NoDerive)];
+    const ARRAY: [OND; 2] = [None, Some(NoDerive)]; //~ NOTE constant defined here
     match [None, Some(NoDerive)] { ARRAY => dbg!(ARRAY), _ => panic!("whoops"), };
-    //~^ ERROR must be annotated with `#[derive(PartialEq)]`
-    //~| NOTE the traits must be derived
-    //~| NOTE StructuralPartialEq.html for details
+    //~^ ERROR constant of non-structural type `NoDerive` in a pattern
+    //~| NOTE constant of non-structural type
 
-    const REPEAT: [OND; 2] = [Some(NoDerive); 2];
+    const REPEAT: [OND; 2] = [Some(NoDerive); 2]; //~ NOTE constant defined here
     match [Some(NoDerive); 2] { REPEAT => dbg!(REPEAT), _ => panic!("whoops"), };
-    //~^ ERROR must be annotated with `#[derive(PartialEq)]`
-    //~| NOTE the traits must be derived
-    //~| NOTE StructuralPartialEq.html for details
+    //~^ ERROR constant of non-structural type `NoDerive` in a pattern
+    //~| NOTE constant of non-structural type
 
-    trait Trait: Sized { const ASSOC: Option<Self>; }
+    trait Trait: Sized { const ASSOC: Option<Self>; } //~ NOTE constant defined here
     impl Trait for NoDerive { const ASSOC: Option<NoDerive> = Some(NoDerive); }
     match Some(NoDerive) { NoDerive::ASSOC => dbg!(NoDerive::ASSOC), _ => panic!("whoops"), };
-    //~^ ERROR must be annotated with `#[derive(PartialEq)]`
-    //~| NOTE the traits must be derived
-    //~| NOTE StructuralPartialEq.html for details
+    //~^ ERROR constant of non-structural type `NoDerive` in a pattern
+    //~| NOTE constant of non-structural type
 
-    const BLOCK: OND = { NoDerive; Some(NoDerive) };
+    const BLOCK: OND = { NoDerive; Some(NoDerive) }; //~ NOTE constant defined here
     match Some(NoDerive) { BLOCK => dbg!(BLOCK), _ => panic!("whoops"), };
-    //~^ ERROR must be annotated with `#[derive(PartialEq)]`
-    //~| NOTE the traits must be derived
-    //~| NOTE StructuralPartialEq.html for details
+    //~^ ERROR constant of non-structural type `NoDerive` in a pattern
+    //~| NOTE constant of non-structural type
 
-    const ADDR_OF: &OND = &Some(NoDerive);
+    const ADDR_OF: &OND = &Some(NoDerive); //~ NOTE constant defined here
     match &Some(NoDerive) { ADDR_OF => dbg!(ADDR_OF), _ => panic!("whoops"), };
-    //~^ ERROR must be annotated with `#[derive(PartialEq)]`
-    //~| NOTE the traits must be derived
-    //~| NOTE StructuralPartialEq.html for details
+    //~^ ERROR constant of non-structural type `NoDerive` in a pattern
+    //~| NOTE constant of non-structural type
 }

tests/ui/consts/const_in_pattern/reject_non_structural.stderr

@@ -1,92 +1,173 @@
-error: to use a constant of type `NoDerive` in a pattern, `NoDerive` must be annotated with `#[derive(PartialEq)]`
-  --> $DIR/reject_non_structural.rs:40:36
+error: constant of non-structural type `NoDerive` in a pattern
+  --> $DIR/reject_non_structural.rs:60:36
    |
+LL | struct NoDerive;
+   | --------------- `NoDerive` must be annotated with `#[derive(PartialEq)]` to be usable in patterns
+...
+LL |     const ENUM: Derive<NoDerive> = Derive::Some(NoDerive);
+   |     ---------------------------- constant defined here
 LL |     match Derive::Some(NoDerive) { ENUM => dbg!(ENUM), _ => panic!("whoops"), };
-   |                                    ^^^^
+   |                                    ^^^^ constant of non-structural type
    |
-   = note: the traits must be derived, manual `impl`s are not sufficient
-   = note: see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
+note: the `PartialEq` trait must be derived, manual `impl`s are not sufficient; see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
+  --> $DIR/reject_non_structural.rs:32:1
+   |
+LL | impl PartialEq for NoDerive { fn eq(&self, _: &Self) -> bool { false } }
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: to use a constant of type `NoDerive` in a pattern, `NoDerive` must be annotated with `#[derive(PartialEq)]`
-  --> $DIR/reject_non_structural.rs:46:28
-   |
-LL |     match Some(NoDerive) { FIELD => dbg!(FIELD), _ => panic!("whoops"), };
-   |                            ^^^^^
-   |
-   = note: the traits must be derived, manual `impl`s are not sufficient
-   = note: see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
-
-error: to use a constant of type `NoDerive` in a pattern, `NoDerive` must be annotated with `#[derive(PartialEq)]`
-  --> $DIR/reject_non_structural.rs:53:27
-   |
-LL |     match Some(NoDerive) {INDIRECT => dbg!(INDIRECT), _ => panic!("whoops"), };
-   |                           ^^^^^^^^
-   |
-   = note: the traits must be derived, manual `impl`s are not sufficient
-   = note: see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
-
-error: to use a constant of type `NoDerive` in a pattern, `NoDerive` must be annotated with `#[derive(PartialEq)]`
-  --> $DIR/reject_non_structural.rs:59:36
-   |
-LL |     match (None, Some(NoDerive)) { TUPLE => dbg!(TUPLE), _ => panic!("whoops"), };
-   |                                    ^^^^^
-   |
-   = note: the traits must be derived, manual `impl`s are not sufficient
-   = note: see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
-
-error: to use a constant of type `NoDerive` in a pattern, `NoDerive` must be annotated with `#[derive(PartialEq)]`
+error: constant of non-structural type `NoDerive` in a pattern
   --> $DIR/reject_non_structural.rs:65:28
    |
+LL | struct NoDerive;
+   | --------------- `NoDerive` must be annotated with `#[derive(PartialEq)]` to be usable in patterns
+...
+LL |     const FIELD: OND = TrivialEq(Some(NoDerive)).0;
+   |     ---------------- constant defined here
+LL |     match Some(NoDerive) { FIELD => dbg!(FIELD), _ => panic!("whoops"), };
+   |                            ^^^^^ constant of non-structural type
+   |
+note: the `PartialEq` trait must be derived, manual `impl`s are not sufficient; see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
+  --> $DIR/reject_non_structural.rs:32:1
+   |
+LL | impl PartialEq for NoDerive { fn eq(&self, _: &Self) -> bool { false } }
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: constant of non-structural type `NoDerive` in a pattern
+  --> $DIR/reject_non_structural.rs:71:27
+   |
+LL | struct NoDerive;
+   | --------------- `NoDerive` must be annotated with `#[derive(PartialEq)]` to be usable in patterns
+...
+LL |     const INDIRECT: OND = NO_DERIVE_SOME;
+   |     ------------------- constant defined here
+LL |     match Some(NoDerive) {INDIRECT => dbg!(INDIRECT), _ => panic!("whoops"), };
+   |                           ^^^^^^^^ constant of non-structural type
+   |
+note: the `PartialEq` trait must be derived, manual `impl`s are not sufficient; see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
+  --> $DIR/reject_non_structural.rs:32:1
+   |
+LL | impl PartialEq for NoDerive { fn eq(&self, _: &Self) -> bool { false } }
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: constant of non-structural type `NoDerive` in a pattern
+  --> $DIR/reject_non_structural.rs:76:36
+   |
+LL | struct NoDerive;
+   | --------------- `NoDerive` must be annotated with `#[derive(PartialEq)]` to be usable in patterns
+...
+LL |     const TUPLE: (OND, OND) = (None, Some(NoDerive));
+   |     ----------------------- constant defined here
+LL |     match (None, Some(NoDerive)) { TUPLE => dbg!(TUPLE), _ => panic!("whoops"), };
+   |                                    ^^^^^ constant of non-structural type
+   |
+note: the `PartialEq` trait must be derived, manual `impl`s are not sufficient; see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
+  --> $DIR/reject_non_structural.rs:32:1
+   |
+LL | impl PartialEq for NoDerive { fn eq(&self, _: &Self) -> bool { false } }
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: constant of non-structural type `NoDerive` in a pattern
+  --> $DIR/reject_non_structural.rs:81:28
+   |
+LL | struct NoDerive;
+   | --------------- `NoDerive` must be annotated with `#[derive(PartialEq)]` to be usable in patterns
+...
+LL |     const TYPE_ASCRIPTION: OND = type_ascribe!(Some(NoDerive), OND);
+   |     -------------------------- constant defined here
 LL |     match Some(NoDerive) { TYPE_ASCRIPTION => dbg!(TYPE_ASCRIPTION), _ => panic!("whoops"), };
-   |                            ^^^^^^^^^^^^^^^
+   |                            ^^^^^^^^^^^^^^^ constant of non-structural type
    |
-   = note: the traits must be derived, manual `impl`s are not sufficient
-   = note: see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
+note: the `PartialEq` trait must be derived, manual `impl`s are not sufficient; see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
+  --> $DIR/reject_non_structural.rs:32:1
+   |
+LL | impl PartialEq for NoDerive { fn eq(&self, _: &Self) -> bool { false } }
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: to use a constant of type `NoDerive` in a pattern, `NoDerive` must be annotated with `#[derive(PartialEq)]`
-  --> $DIR/reject_non_structural.rs:71:36
+error: constant of non-structural type `NoDerive` in a pattern
+  --> $DIR/reject_non_structural.rs:86:36
    |
+LL | struct NoDerive;
+   | --------------- `NoDerive` must be annotated with `#[derive(PartialEq)]` to be usable in patterns
+...
+LL |     const ARRAY: [OND; 2] = [None, Some(NoDerive)];
+   |     --------------------- constant defined here
 LL |     match [None, Some(NoDerive)] { ARRAY => dbg!(ARRAY), _ => panic!("whoops"), };
-   |                                    ^^^^^
+   |                                    ^^^^^ constant of non-structural type
    |
-   = note: the traits must be derived, manual `impl`s are not sufficient
-   = note: see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
+note: the `PartialEq` trait must be derived, manual `impl`s are not sufficient; see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
+  --> $DIR/reject_non_structural.rs:32:1
+   |
+LL | impl PartialEq for NoDerive { fn eq(&self, _: &Self) -> bool { false } }
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: to use a constant of type `NoDerive` in a pattern, `NoDerive` must be annotated with `#[derive(PartialEq)]`
-  --> $DIR/reject_non_structural.rs:77:33
+error: constant of non-structural type `NoDerive` in a pattern
+  --> $DIR/reject_non_structural.rs:91:33
    |
+LL | struct NoDerive;
+   | --------------- `NoDerive` must be annotated with `#[derive(PartialEq)]` to be usable in patterns
+...
+LL |     const REPEAT: [OND; 2] = [Some(NoDerive); 2];
+   |     ---------------------- constant defined here
 LL |     match [Some(NoDerive); 2] { REPEAT => dbg!(REPEAT), _ => panic!("whoops"), };
-   |                                 ^^^^^^
+   |                                 ^^^^^^ constant of non-structural type
    |
-   = note: the traits must be derived, manual `impl`s are not sufficient
-   = note: see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
+note: the `PartialEq` trait must be derived, manual `impl`s are not sufficient; see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
+  --> $DIR/reject_non_structural.rs:32:1
+   |
+LL | impl PartialEq for NoDerive { fn eq(&self, _: &Self) -> bool { false } }
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: to use a constant of type `NoDerive` in a pattern, `NoDerive` must be annotated with `#[derive(PartialEq)]`
-  --> $DIR/reject_non_structural.rs:84:28
+error: constant of non-structural type `NoDerive` in a pattern
+  --> $DIR/reject_non_structural.rs:97:28
    |
+LL | struct NoDerive;
+   | --------------- `NoDerive` must be annotated with `#[derive(PartialEq)]` to be usable in patterns
+...
+LL |     trait Trait: Sized { const ASSOC: Option<Self>; }
+   |     ------------------   ------------------------- constant defined here
+LL |     impl Trait for NoDerive { const ASSOC: Option<NoDerive> = Some(NoDerive); }
 LL |     match Some(NoDerive) { NoDerive::ASSOC => dbg!(NoDerive::ASSOC), _ => panic!("whoops"), };
-   |                            ^^^^^^^^^^^^^^^
+   |                            ^^^^^^^^^^^^^^^ constant of non-structural type
    |
-   = note: the traits must be derived, manual `impl`s are not sufficient
-   = note: see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
+note: the `PartialEq` trait must be derived, manual `impl`s are not sufficient; see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
+  --> $DIR/reject_non_structural.rs:32:1
+   |
+LL | impl PartialEq for NoDerive { fn eq(&self, _: &Self) -> bool { false } }
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: to use a constant of type `NoDerive` in a pattern, `NoDerive` must be annotated with `#[derive(PartialEq)]`
-  --> $DIR/reject_non_structural.rs:90:28
+error: constant of non-structural type `NoDerive` in a pattern
+  --> $DIR/reject_non_structural.rs:102:28
    |
+LL | struct NoDerive;
+   | --------------- `NoDerive` must be annotated with `#[derive(PartialEq)]` to be usable in patterns
+...
+LL |     const BLOCK: OND = { NoDerive; Some(NoDerive) };
+   |     ---------------- constant defined here
 LL |     match Some(NoDerive) { BLOCK => dbg!(BLOCK), _ => panic!("whoops"), };
-   |                            ^^^^^
+   |                            ^^^^^ constant of non-structural type
    |
-   = note: the traits must be derived, manual `impl`s are not sufficient
-   = note: see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
+note: the `PartialEq` trait must be derived, manual `impl`s are not sufficient; see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
+  --> $DIR/reject_non_structural.rs:32:1
+   |
+LL | impl PartialEq for NoDerive { fn eq(&self, _: &Self) -> bool { false } }
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: to use a constant of type `NoDerive` in a pattern, `NoDerive` must be annotated with `#[derive(PartialEq)]`
-  --> $DIR/reject_non_structural.rs:96:29
+error: constant of non-structural type `NoDerive` in a pattern
+  --> $DIR/reject_non_structural.rs:107:29
    |
+LL | struct NoDerive;
+   | --------------- `NoDerive` must be annotated with `#[derive(PartialEq)]` to be usable in patterns
+...
+LL |     const ADDR_OF: &OND = &Some(NoDerive);
+   |     ------------------- constant defined here
 LL |     match &Some(NoDerive) { ADDR_OF => dbg!(ADDR_OF), _ => panic!("whoops"), };
-   |                             ^^^^^^^
+   |                             ^^^^^^^ constant of non-structural type
    |
-   = note: the traits must be derived, manual `impl`s are not sufficient
-   = note: see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
+note: the `PartialEq` trait must be derived, manual `impl`s are not sufficient; see https://doc.rust-lang.org/stable/std/marker/trait.StructuralPartialEq.html for details
+  --> $DIR/reject_non_structural.rs:32:1
+   |
+LL | impl PartialEq for NoDerive { fn eq(&self, _: &Self) -> bool { false } }
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: aborting due to 10 previous errors
 

tests/ui/consts/const_refs_to_static_fail_invalid.rs

@@ -11,7 +11,7 @@ fn invalid() {
 
     // This must be rejected here (or earlier), since it's not a valid `&bool`.
     match &true {
-        C => {} //~ERROR: could not evaluate constant pattern
+        C => {} // ok, `const` already emitted an error
         _ => {}
     }
 }
@@ -27,7 +27,7 @@ fn extern_() {
 
     // This must be rejected here (or earlier), since the pattern cannot be read.
     match &0 {
-        C => {} //~ERROR: could not evaluate constant pattern
+        C => {} // ok, `const` already emitted an error
         _ => {}
     }
 }
@@ -42,7 +42,7 @@ fn mutable() {
     // This *must not build*, the constant we are matching against
     // could change its value!
     match &42 {
-        C => {} //~ERROR: could not evaluate constant pattern
+        C => {} // ok, `const` already emitted an error
         _ => {}
     }
 }

tests/ui/consts/const_refs_to_static_fail_invalid.stderr

@@ -31,24 +31,6 @@ LL |     const C: &i32 = unsafe { &S_MUT };
                HEX_DUMP
            }
 
-error: could not evaluate constant pattern
-  --> $DIR/const_refs_to_static_fail_invalid.rs:14:9
-   |
-LL |         C => {}
-   |         ^
-
-error: could not evaluate constant pattern
-  --> $DIR/const_refs_to_static_fail_invalid.rs:30:9
-   |
-LL |         C => {}
-   |         ^
-
-error: could not evaluate constant pattern
-  --> $DIR/const_refs_to_static_fail_invalid.rs:45:9
-   |
-LL |         C => {}
-   |         ^
-
-error: aborting due to 6 previous errors
+error: aborting due to 3 previous errors
 
 For more information about this error, try `rustc --explain E0080`.