Rollup merge of #118833 - Urgau:lint_function_pointer_comparisons, r=cjgillot

Add lint against function pointer comparisons

This is kind of a follow-up to https://github.com/rust-lang/rust/pull/117758 where we added a lint against wide pointer comparisons for being ambiguous and unreliable; well function pointer comparisons are also unreliable. We should IMO follow a similar logic and warn people about it.

-----

## `unpredictable_function_pointer_comparisons`

*warn-by-default*

The `unpredictable_function_pointer_comparisons` lint checks comparison of function pointer as the operands.

### Example

```rust
fn foo() {}
let a = foo as fn();

let _ = a == foo;
```

### 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 function could have the same address after being merged together.

----

This PR also uplift the very similar `clippy::fn_address_comparisons` lint, which only linted on if one of the operand was an `ty::FnDef` while this PR lints proposes to lint on all `ty::FnPtr` and `ty::FnDef`.

```@rustbot``` labels +I-lang-nominated

~~Edit: Blocked on https://github.com/rust-lang/libs-team/issues/323 being accepted and it's follow-up pr~~

11 files changed, 83 insertions, 170 deletions

diff --git a/src/tools/clippy/clippy_lints/src/declared_lints.rs b/src/tools/clippy/clippy_lints/src/declared_lints.rs
index c4a0c8f1865..022ed180ed8 100644
--- a/src/tools/clippy/clippy_lints/src/declared_lints.rs
+++ b/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,
diff --git a/src/tools/clippy/clippy_lints/src/deprecated_lints.rs b/src/tools/clippy/clippy_lints/src/deprecated_lints.rs
index 77dbe9b78a1..3ea792d8b83 100644
--- a/src/tools/clippy/clippy_lints/src/deprecated_lints.rs
+++ b/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"),
diff --git a/src/tools/clippy/clippy_lints/src/lib.rs b/src/tools/clippy/clippy_lints/src/lib.rs
index c9064df25ac..e80cca6e7db 100644
--- a/src/tools/clippy/clippy_lints/src/lib.rs
+++ b/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));
diff --git a/src/tools/clippy/clippy_lints/src/unnamed_address.rs b/src/tools/clippy/clippy_lints/src/unnamed_address.rs
deleted file mode 100644
index cd2dacc9f09..00000000000
--- a/src/tools/clippy/clippy_lints/src/unnamed_address.rs
+++ /dev/null
@@ -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",
-            );
-        }
-    }
-}
diff --git a/src/tools/clippy/tests/ui/fn_address_comparisons.rs b/src/tools/clippy/tests/ui/fn_address_comparisons.rs
deleted file mode 100644
index 35535bd4fdd..00000000000
--- a/src/tools/clippy/tests/ui/fn_address_comparisons.rs
+++ /dev/null
@@ -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;
-}
diff --git a/src/tools/clippy/tests/ui/fn_address_comparisons.stderr b/src/tools/clippy/tests/ui/fn_address_comparisons.stderr
deleted file mode 100644
index e6de7e35807..00000000000
--- a/src/tools/clippy/tests/ui/fn_address_comparisons.stderr
+++ /dev/null
@@ -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
-
diff --git a/src/tools/clippy/tests/ui/rename.fixed b/src/tools/clippy/tests/ui/rename.fixed
index 0d6e07aa546..47149622ef7 100644
--- a/src/tools/clippy/tests/ui/rename.fixed
+++ b/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`
diff --git a/src/tools/clippy/tests/ui/rename.rs b/src/tools/clippy/tests/ui/rename.rs
index 2ac59718786..7a78a5d280d 100644
--- a/src/tools/clippy/tests/ui/rename.rs
+++ b/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`
diff --git a/src/tools/clippy/tests/ui/rename.stderr b/src/tools/clippy/tests/ui/rename.stderr
index a5ae727b7ee..dc24bc16d0e 100644
--- a/src/tools/clippy/tests/ui/rename.stderr
+++ b/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
 
diff --git a/src/tools/miri/tests/pass/function_pointers.rs b/src/tools/miri/tests/pass/function_pointers.rs
index a5c4bc5e0d9..7145be334a1 100644
--- a/src/tools/miri/tests/pass/function_pointers.rs
+++ b/src/tools/miri/tests/pass/function_pointers.rs
@@ -1,3 +1,5 @@
+#![allow(unpredictable_function_pointer_comparisons)]
+
 use std::mem;
 
 trait Answer {
diff --git a/src/tools/miri/tests/pass/issues/issue-91636.rs b/src/tools/miri/tests/pass/issues/issue-91636.rs
index 00370165812..d0cadcd2c70 100644
--- a/src/tools/miri/tests/pass/issues/issue-91636.rs
+++ b/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 {