Add borrow_as_ptr lint

Closes: #6995

Signed-off-by: Federico Guerinoni <guerinoni.federico@gmail.com>
Co-authored-by: Paolo Barbolini <paolo@paolo565.org>

CHANGELOG.md

@@ -2887,6 +2887,7 @@ Released 2018-09-13
 [`blocks_in_if_conditions`]: https://rust-lang.github.io/rust-clippy/master/index.html#blocks_in_if_conditions
 [`bool_assert_comparison`]: https://rust-lang.github.io/rust-clippy/master/index.html#bool_assert_comparison
 [`bool_comparison`]: https://rust-lang.github.io/rust-clippy/master/index.html#bool_comparison
+[`borrow_as_ptr`]: https://rust-lang.github.io/rust-clippy/master/index.html#borrow_as_ptr
 [`borrow_interior_mutable_const`]: https://rust-lang.github.io/rust-clippy/master/index.html#borrow_interior_mutable_const
 [`borrowed_box`]: https://rust-lang.github.io/rust-clippy/master/index.html#borrowed_box
 [`box_collection`]: https://rust-lang.github.io/rust-clippy/master/index.html#box_collection

README.md

@@ -5,7 +5,7 @@
 
 A collection of lints to catch common mistakes and improve your [Rust](https://github.com/rust-lang/rust) code.
 
-[There are over 450 lints included in this crate!](https://rust-lang.github.io/rust-clippy/master/index.html)
+[There are over 500 lints included in this crate!](https://rust-lang.github.io/rust-clippy/master/index.html)
 
 Lints are divided into categories, each with a default [lint level](https://doc.rust-lang.org/rustc/lints/levels.html).
 You can choose how much Clippy is supposed to ~~annoy~~ help you by changing the lint level by category.

clippy_lints/src/borrow_as_ptr.rs

@@ -0,0 +1,97 @@
+use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::is_no_std_crate;
+use clippy_utils::source::snippet_opt;
+use clippy_utils::{meets_msrv, msrvs};
+use if_chain::if_chain;
+use rustc_errors::Applicability;
+use rustc_hir::{BorrowKind, Expr, ExprKind, Mutability, TyKind};
+use rustc_lint::{LateContext, LateLintPass};
+use rustc_semver::RustcVersion;
+use rustc_session::{declare_tool_lint, impl_lint_pass};
+
+declare_clippy_lint! {
+    /// ### What it does
+    /// Checks for the usage of `&expr as *const T` or
+    /// `&mut expr as *mut T`, and suggest using `ptr::addr_of` or
+    /// `ptr::addr_of_mut` instead.
+    ///
+    /// ### Why is this bad?
+    /// This would improve readability and avoid creating a reference
+    /// that points to an uninitialized value or unaligned place.
+    /// Read the `ptr::addr_of` docs for more information.
+    ///
+    /// ### Example
+    /// ```rust
+    /// let val = 1;
+    /// let p = &val as *const i32;
+    ///
+    /// let mut val_mut = 1;
+    /// let p_mut = &mut val_mut as *mut i32;
+    /// ```
+    /// Use instead:
+    /// ```rust
+    /// let val = 1;
+    /// let p = std::ptr::addr_of!(val);
+    ///
+    /// let mut val_mut = 1;
+    /// let p_mut = std::ptr::addr_of_mut!(val_mut);
+    /// ```
+    #[clippy::version = "1.60.0"]
+    pub BORROW_AS_PTR,
+    pedantic,
+    "borrowing just to cast to a raw pointer"
+}
+
+impl_lint_pass!(BorrowAsPtr => [BORROW_AS_PTR]);
+
+pub struct BorrowAsPtr {
+    msrv: Option<RustcVersion>,
+}
+
+impl BorrowAsPtr {
+    #[must_use]
+    pub fn new(msrv: Option<RustcVersion>) -> Self {
+        Self { msrv }
+    }
+}
+
+impl<'tcx> LateLintPass<'tcx> for BorrowAsPtr {
+    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
+        if !meets_msrv(self.msrv.as_ref(), &msrvs::BORROW_AS_PTR) {
+            return;
+        }
+
+        if expr.span.from_expansion() {
+            return;
+        }
+
+        if_chain! {
+            if let ExprKind::Cast(left_expr, ty) = &expr.kind;
+            if let TyKind::Ptr(_) = ty.kind;
+            if let ExprKind::AddrOf(BorrowKind::Ref, mutability, e) = &left_expr.kind;
+
+            then {
+                let core_or_std = if is_no_std_crate(cx) { "core" } else { "std" };
+                let macro_name = match mutability {
+                    Mutability::Not => "addr_of",
+                    Mutability::Mut => "addr_of_mut",
+                };
+
+                span_lint_and_sugg(
+                    cx,
+                    BORROW_AS_PTR,
+                    expr.span,
+                    "borrow as raw pointer",
+                    "try",
+                    format!(
+                        "{}::ptr::{}!({})",
+                        core_or_std,
+                        macro_name,
+                        snippet_opt(cx, e.span).unwrap()
+                    ),
+                    Applicability::MachineApplicable,
+                );
+            }
+        }
+    }
+}

clippy_lints/src/lib.register_lints.rs

@@ -59,6 +59,7 @@ store.register_lints(&[
     bool_assert_comparison::BOOL_ASSERT_COMPARISON,
     booleans::LOGIC_BUG,
     booleans::NONMINIMAL_BOOL,
+    borrow_as_ptr::BORROW_AS_PTR,
     bytecount::NAIVE_BYTECOUNT,
     cargo_common_metadata::CARGO_COMMON_METADATA,
     case_sensitive_file_extension_comparisons::CASE_SENSITIVE_FILE_EXTENSION_COMPARISONS,

clippy_lints/src/lib.register_pedantic.rs

@@ -7,6 +7,7 @@ store.register_group(true, "clippy::pedantic", Some("clippy_pedantic"), vec![
     LintId::of(await_holding_invalid::AWAIT_HOLDING_LOCK),
     LintId::of(await_holding_invalid::AWAIT_HOLDING_REFCELL_REF),
     LintId::of(bit_mask::VERBOSE_BIT_MASK),
+    LintId::of(borrow_as_ptr::BORROW_AS_PTR),
     LintId::of(bytecount::NAIVE_BYTECOUNT),
     LintId::of(case_sensitive_file_extension_comparisons::CASE_SENSITIVE_FILE_EXTENSION_COMPARISONS),
     LintId::of(casts::CAST_LOSSLESS),

clippy_lints/src/lib.rs

@@ -174,6 +174,7 @@ mod blacklisted_name;
 mod blocks_in_if_conditions;
 mod bool_assert_comparison;
 mod booleans;
+mod borrow_as_ptr;
 mod bytecount;
 mod cargo_common_metadata;
 mod case_sensitive_file_extension_comparisons;
@@ -857,6 +858,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     store.register_late_pass(|| Box::new(return_self_not_must_use::ReturnSelfNotMustUse));
     store.register_late_pass(|| Box::new(init_numbered_fields::NumberedFields));
     store.register_early_pass(|| Box::new(single_char_lifetime_names::SingleCharLifetimeNames));
+    store.register_late_pass(move || Box::new(borrow_as_ptr::BorrowAsPtr::new(msrv)));
     // add lints here, do not remove this comment, it's used in `new_lint`
 }
 

clippy_utils/src/msrvs.rs

@@ -14,6 +14,7 @@ macro_rules! msrv_aliases {
 msrv_aliases! {
     1,53,0 { OR_PATTERNS }
     1,52,0 { STR_SPLIT_ONCE }
+    1,51,0 { BORROW_AS_PTR }
     1,50,0 { BOOL_THEN }
     1,47,0 { TAU }
     1,46,0 { CONST_IF_MATCH }

tests/ui/as_conversions.rs

@@ -1,6 +1,7 @@
 // aux-build:macro_rules.rs
 
 #![warn(clippy::as_conversions)]
+#![allow(clippy::borrow_as_ptr)]
 
 #[macro_use]
 extern crate macro_rules;

tests/ui/as_conversions.stderr

@@ -1,5 +1,5 @@
 error: using a potentially dangerous silent `as` conversion
-  --> $DIR/as_conversions.rs:14:13
+  --> $DIR/as_conversions.rs:15:13
    |
 LL |     let i = 0u32 as u64;
    |             ^^^^^^^^^^^
@@ -8,7 +8,7 @@ LL |     let i = 0u32 as u64;
    = help: consider using a safe wrapper for this conversion
 
 error: using a potentially dangerous silent `as` conversion
-  --> $DIR/as_conversions.rs:16:13
+  --> $DIR/as_conversions.rs:17:13
    |
 LL |     let j = &i as *const u64 as *mut u64;
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -16,7 +16,7 @@ LL |     let j = &i as *const u64 as *mut u64;
    = help: consider using a safe wrapper for this conversion
 
 error: using a potentially dangerous silent `as` conversion
-  --> $DIR/as_conversions.rs:16:13
+  --> $DIR/as_conversions.rs:17:13
    |
 LL |     let j = &i as *const u64 as *mut u64;
    |             ^^^^^^^^^^^^^^^^

tests/ui/borrow_as_ptr.fixed

@@ -0,0 +1,10 @@
+// run-rustfix
+#![warn(clippy::borrow_as_ptr)]
+
+fn main() {
+    let val = 1;
+    let _p = std::ptr::addr_of!(val);
+
+    let mut val_mut = 1;
+    let _p_mut = std::ptr::addr_of_mut!(val_mut);
+}

tests/ui/borrow_as_ptr.rs

@@ -0,0 +1,10 @@
+// run-rustfix
+#![warn(clippy::borrow_as_ptr)]
+
+fn main() {
+    let val = 1;
+    let _p = &val as *const i32;
+
+    let mut val_mut = 1;
+    let _p_mut = &mut val_mut as *mut i32;
+}

tests/ui/borrow_as_ptr.stderr

@@ -0,0 +1,16 @@
+error: borrow as raw pointer
+  --> $DIR/borrow_as_ptr.rs:6:14
+   |
+LL |     let _p = &val as *const i32;
+   |              ^^^^^^^^^^^^^^^^^^ help: try: `std::ptr::addr_of!(val)`
+   |
+   = note: `-D clippy::borrow-as-ptr` implied by `-D warnings`
+
+error: borrow as raw pointer
+  --> $DIR/borrow_as_ptr.rs:9:18
+   |
+LL |     let _p_mut = &mut val_mut as *mut i32;
+   |                  ^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `std::ptr::addr_of_mut!(val_mut)`
+
+error: aborting due to 2 previous errors
+

tests/ui/borrow_as_ptr_no_std.fixed

@@ -0,0 +1,22 @@
+// run-rustfix
+#![warn(clippy::borrow_as_ptr)]
+#![feature(lang_items, start, libc)]
+#![no_std]
+
+#[start]
+fn main(_argc: isize, _argv: *const *const u8) -> isize {
+    let val = 1;
+    let _p = core::ptr::addr_of!(val);
+
+    let mut val_mut = 1;
+    let _p_mut = core::ptr::addr_of_mut!(val_mut);
+    0
+}
+
+#[panic_handler]
+fn panic(_info: &core::panic::PanicInfo) -> ! {
+    loop {}
+}
+
+#[lang = "eh_personality"]
+extern "C" fn eh_personality() {}

tests/ui/borrow_as_ptr_no_std.rs

@@ -0,0 +1,22 @@
+// run-rustfix
+#![warn(clippy::borrow_as_ptr)]
+#![feature(lang_items, start, libc)]
+#![no_std]
+
+#[start]
+fn main(_argc: isize, _argv: *const *const u8) -> isize {
+    let val = 1;
+    let _p = &val as *const i32;
+
+    let mut val_mut = 1;
+    let _p_mut = &mut val_mut as *mut i32;
+    0
+}
+
+#[panic_handler]
+fn panic(_info: &core::panic::PanicInfo) -> ! {
+    loop {}
+}
+
+#[lang = "eh_personality"]
+extern "C" fn eh_personality() {}

tests/ui/borrow_as_ptr_no_std.stderr

@@ -0,0 +1,16 @@
+error: borrow as raw pointer
+  --> $DIR/borrow_as_ptr_no_std.rs:9:14
+   |
+LL |     let _p = &val as *const i32;
+   |              ^^^^^^^^^^^^^^^^^^ help: try: `core::ptr::addr_of!(val)`
+   |
+   = note: `-D clippy::borrow-as-ptr` implied by `-D warnings`
+
+error: borrow as raw pointer
+  --> $DIR/borrow_as_ptr_no_std.rs:12:18
+   |
+LL |     let _p_mut = &mut val_mut as *mut i32;
+   |                  ^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `core::ptr::addr_of_mut!(val_mut)`
+
+error: aborting due to 2 previous errors
+

tests/ui/cast_alignment.rs

@@ -4,7 +4,13 @@
 extern crate libc;
 
 #[warn(clippy::cast_ptr_alignment)]
-#[allow(clippy::no_effect, clippy::unnecessary_operation, clippy::cast_lossless)]
+#[allow(
+    clippy::no_effect,
+    clippy::unnecessary_operation,
+    clippy::cast_lossless,
+    clippy::borrow_as_ptr
+)]
+
 fn main() {
     /* These should be warned against */
 

tests/ui/cast_alignment.stderr

@@ -1,5 +1,5 @@
 error: casting from `*const u8` to a more-strictly-aligned pointer (`*const u16`) (1 < 2 bytes)
-  --> $DIR/cast_alignment.rs:12:5
+  --> $DIR/cast_alignment.rs:18:5
    |
 LL |     (&1u8 as *const u8) as *const u16;
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -7,19 +7,19 @@ LL |     (&1u8 as *const u8) as *const u16;
    = note: `-D clippy::cast-ptr-alignment` implied by `-D warnings`
 
 error: casting from `*mut u8` to a more-strictly-aligned pointer (`*mut u16`) (1 < 2 bytes)
-  --> $DIR/cast_alignment.rs:13:5
+  --> $DIR/cast_alignment.rs:19:5
    |
 LL |     (&mut 1u8 as *mut u8) as *mut u16;
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: casting from `*const u8` to a more-strictly-aligned pointer (`*const u16`) (1 < 2 bytes)
-  --> $DIR/cast_alignment.rs:16:5
+  --> $DIR/cast_alignment.rs:22:5
    |
 LL |     (&1u8 as *const u8).cast::<u16>();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: casting from `*mut u8` to a more-strictly-aligned pointer (`*mut u16`) (1 < 2 bytes)
-  --> $DIR/cast_alignment.rs:17:5
+  --> $DIR/cast_alignment.rs:23:5
    |
 LL |     (&mut 1u8 as *mut u8).cast::<u16>();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

tests/ui/cast_ref_to_mut.rs

@@ -1,5 +1,5 @@
 #![warn(clippy::cast_ref_to_mut)]
-#![allow(clippy::no_effect)]
+#![allow(clippy::no_effect, clippy::borrow_as_ptr)]
 
 extern "C" {
     // N.B., mutability can be easily incorrect in FFI calls -- as

tests/ui/mutex_atomic.rs

@@ -1,6 +1,7 @@
 #![warn(clippy::all)]
 #![warn(clippy::mutex_integer)]
 #![warn(clippy::mutex_atomic)]
+#![allow(clippy::borrow_as_ptr)]
 
 fn main() {
     use std::sync::Mutex;

tests/ui/mutex_atomic.stderr

@@ -1,5 +1,5 @@
 error: consider using an `AtomicBool` instead of a `Mutex` here; if you just want the locking behavior and not the internal type, consider using `Mutex<()>`
-  --> $DIR/mutex_atomic.rs:7:5
+  --> $DIR/mutex_atomic.rs:8:5
    |
 LL |     Mutex::new(true);
    |     ^^^^^^^^^^^^^^^^
@@ -7,31 +7,31 @@ LL |     Mutex::new(true);
    = note: `-D clippy::mutex-atomic` implied by `-D warnings`
 
 error: consider using an `AtomicUsize` instead of a `Mutex` here; if you just want the locking behavior and not the internal type, consider using `Mutex<()>`
-  --> $DIR/mutex_atomic.rs:8:5
+  --> $DIR/mutex_atomic.rs:9:5
    |
 LL |     Mutex::new(5usize);
    |     ^^^^^^^^^^^^^^^^^^
 
 error: consider using an `AtomicIsize` instead of a `Mutex` here; if you just want the locking behavior and not the internal type, consider using `Mutex<()>`
-  --> $DIR/mutex_atomic.rs:9:5
+  --> $DIR/mutex_atomic.rs:10:5
    |
 LL |     Mutex::new(9isize);
    |     ^^^^^^^^^^^^^^^^^^
 
 error: consider using an `AtomicPtr` instead of a `Mutex` here; if you just want the locking behavior and not the internal type, consider using `Mutex<()>`
-  --> $DIR/mutex_atomic.rs:11:5
+  --> $DIR/mutex_atomic.rs:12:5
    |
 LL |     Mutex::new(&x as *const u32);
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: consider using an `AtomicPtr` instead of a `Mutex` here; if you just want the locking behavior and not the internal type, consider using `Mutex<()>`
-  --> $DIR/mutex_atomic.rs:12:5
+  --> $DIR/mutex_atomic.rs:13:5
    |
 LL |     Mutex::new(&mut x as *mut u32);
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: consider using an `AtomicUsize` instead of a `Mutex` here; if you just want the locking behavior and not the internal type, consider using `Mutex<()>`
-  --> $DIR/mutex_atomic.rs:13:5
+  --> $DIR/mutex_atomic.rs:14:5
    |
 LL |     Mutex::new(0u32);
    |     ^^^^^^^^^^^^^^^^
@@ -39,7 +39,7 @@ LL |     Mutex::new(0u32);
    = note: `-D clippy::mutex-integer` implied by `-D warnings`
 
 error: consider using an `AtomicIsize` instead of a `Mutex` here; if you just want the locking behavior and not the internal type, consider using `Mutex<()>`
-  --> $DIR/mutex_atomic.rs:14:5
+  --> $DIR/mutex_atomic.rs:15:5
    |
 LL |     Mutex::new(0i32);
    |     ^^^^^^^^^^^^^^^^

tests/ui/or_fun_call.fixed

@@ -2,7 +2,7 @@
 
 #![warn(clippy::or_fun_call)]
 #![allow(dead_code)]
-#![allow(clippy::unnecessary_wraps)]
+#![allow(clippy::unnecessary_wraps, clippy::borrow_as_ptr)]
 
 use std::collections::BTreeMap;
 use std::collections::HashMap;

tests/ui/or_fun_call.rs

@@ -2,7 +2,7 @@
 
 #![warn(clippy::or_fun_call)]
 #![allow(dead_code)]
-#![allow(clippy::unnecessary_wraps)]
+#![allow(clippy::unnecessary_wraps, clippy::borrow_as_ptr)]
 
 use std::collections::BTreeMap;
 use std::collections::HashMap;

tests/ui/transmute.rs

@@ -1,4 +1,4 @@
-#![allow(dead_code)]
+#![allow(dead_code, clippy::borrow_as_ptr)]
 
 extern crate core;
 

tests/ui/transmute_ptr_to_ptr.rs

@@ -1,4 +1,5 @@
 #![warn(clippy::transmute_ptr_to_ptr)]
+#![allow(clippy::borrow_as_ptr)]
 
 // Make sure we can modify lifetimes, which is one of the recommended uses
 // of transmute

tests/ui/transmute_ptr_to_ptr.stderr

@@ -1,5 +1,5 @@
 error: transmute from a pointer to a pointer
-  --> $DIR/transmute_ptr_to_ptr.rs:29:29
+  --> $DIR/transmute_ptr_to_ptr.rs:30:29
    |
 LL |         let _: *const f32 = std::mem::transmute(ptr);
    |                             ^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `ptr as *const f32`
@@ -7,31 +7,31 @@ LL |         let _: *const f32 = std::mem::transmute(ptr);
    = note: `-D clippy::transmute-ptr-to-ptr` implied by `-D warnings`
 
 error: transmute from a pointer to a pointer
-  --> $DIR/transmute_ptr_to_ptr.rs:30:27
+  --> $DIR/transmute_ptr_to_ptr.rs:31:27
    |
 LL |         let _: *mut f32 = std::mem::transmute(mut_ptr);
    |                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `mut_ptr as *mut f32`
 
 error: transmute from a reference to a reference
-  --> $DIR/transmute_ptr_to_ptr.rs:32:23
+  --> $DIR/transmute_ptr_to_ptr.rs:33:23
    |
 LL |         let _: &f32 = std::mem::transmute(&1u32);
    |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `&*(&1u32 as *const u32 as *const f32)`
 
 error: transmute from a reference to a reference
-  --> $DIR/transmute_ptr_to_ptr.rs:33:23
+  --> $DIR/transmute_ptr_to_ptr.rs:34:23
    |
 LL |         let _: &f64 = std::mem::transmute(&1f32);
    |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `&*(&1f32 as *const f32 as *const f64)`
 
 error: transmute from a reference to a reference
-  --> $DIR/transmute_ptr_to_ptr.rs:36:27
+  --> $DIR/transmute_ptr_to_ptr.rs:37:27
    |
 LL |         let _: &mut f32 = std::mem::transmute(&mut 1u32);
    |                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `&mut *(&mut 1u32 as *mut u32 as *mut f32)`
 
 error: transmute from a reference to a reference
-  --> $DIR/transmute_ptr_to_ptr.rs:37:37
+  --> $DIR/transmute_ptr_to_ptr.rs:38:37
    |
 LL |         let _: &GenericParam<f32> = std::mem::transmute(&GenericParam { t: 1u32 });
    |                                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `&*(&GenericParam { t: 1u32 } as *const GenericParam<u32> as *const GenericParam<f32>)`

tests/ui/transmutes_expressible_as_ptr_casts.fixed

@@ -4,8 +4,7 @@
 // would otherwise be responsible for
 #![warn(clippy::useless_transmute)]
 #![warn(clippy::transmute_ptr_to_ptr)]
-#![allow(unused_unsafe)]
-#![allow(dead_code)]
+#![allow(dead_code, unused_unsafe, clippy::borrow_as_ptr)]
 
 use std::mem::{size_of, transmute};
 

tests/ui/transmutes_expressible_as_ptr_casts.rs

@@ -4,8 +4,7 @@
 // would otherwise be responsible for
 #![warn(clippy::useless_transmute)]
 #![warn(clippy::transmute_ptr_to_ptr)]
-#![allow(unused_unsafe)]
-#![allow(dead_code)]
+#![allow(dead_code, unused_unsafe, clippy::borrow_as_ptr)]
 
 use std::mem::{size_of, transmute};
 

tests/ui/transmutes_expressible_as_ptr_casts.stderr

@@ -1,5 +1,5 @@
 error: transmute from an integer to a pointer
-  --> $DIR/transmutes_expressible_as_ptr_casts.rs:19:39
+  --> $DIR/transmutes_expressible_as_ptr_casts.rs:18:39
    |
 LL |     let _ptr_i32_transmute = unsafe { transmute::<usize, *const i32>(usize::MAX) };
    |                                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `usize::MAX as *const i32`
@@ -7,7 +7,7 @@ LL |     let _ptr_i32_transmute = unsafe { transmute::<usize, *const i32>(usize:
    = note: `-D clippy::useless-transmute` implied by `-D warnings`
 
 error: transmute from a pointer to a pointer
-  --> $DIR/transmutes_expressible_as_ptr_casts.rs:23:38
+  --> $DIR/transmutes_expressible_as_ptr_casts.rs:22:38
    |
 LL |     let _ptr_i8_transmute = unsafe { transmute::<*const i32, *const i8>(ptr_i32) };
    |                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `ptr_i32 as *const i8`
@@ -15,13 +15,13 @@ LL |     let _ptr_i8_transmute = unsafe { transmute::<*const i32, *const i8>(ptr
    = note: `-D clippy::transmute-ptr-to-ptr` implied by `-D warnings`
 
 error: transmute from a pointer to a pointer
-  --> $DIR/transmutes_expressible_as_ptr_casts.rs:29:46
+  --> $DIR/transmutes_expressible_as_ptr_casts.rs:28:46
    |
 LL |     let _ptr_to_unsized_transmute = unsafe { transmute::<*const [i32], *const [u16]>(slice_ptr) };
    |                                              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `slice_ptr as *const [u16]`
 
 error: transmute from `*const i32` to `usize` which could be expressed as a pointer cast instead
-  --> $DIR/transmutes_expressible_as_ptr_casts.rs:35:50
+  --> $DIR/transmutes_expressible_as_ptr_casts.rs:34:50
    |
 LL |     let _usize_from_int_ptr_transmute = unsafe { transmute::<*const i32, usize>(ptr_i32) };
    |                                                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `ptr_i32 as usize`
@@ -29,25 +29,25 @@ LL |     let _usize_from_int_ptr_transmute = unsafe { transmute::<*const i32, us
    = note: `-D clippy::transmutes-expressible-as-ptr-casts` implied by `-D warnings`
 
 error: transmute from a reference to a pointer
-  --> $DIR/transmutes_expressible_as_ptr_casts.rs:41:41
+  --> $DIR/transmutes_expressible_as_ptr_casts.rs:40:41
    |
 LL |     let _array_ptr_transmute = unsafe { transmute::<&[i32; 4], *const [i32; 4]>(array_ref) };
    |                                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `array_ref as *const [i32; 4]`
 
 error: transmute from `fn(usize) -> u8 {main::foo}` to `*const usize` which could be expressed as a pointer cast instead
-  --> $DIR/transmutes_expressible_as_ptr_casts.rs:49:41
+  --> $DIR/transmutes_expressible_as_ptr_casts.rs:48:41
    |
 LL |     let _usize_ptr_transmute = unsafe { transmute::<fn(usize) -> u8, *const usize>(foo) };
    |                                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `foo as *const usize`
 
 error: transmute from `fn(usize) -> u8 {main::foo}` to `usize` which could be expressed as a pointer cast instead
-  --> $DIR/transmutes_expressible_as_ptr_casts.rs:53:49
+  --> $DIR/transmutes_expressible_as_ptr_casts.rs:52:49
    |
 LL |     let _usize_from_fn_ptr_transmute = unsafe { transmute::<fn(usize) -> u8, usize>(foo) };
    |                                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `foo as usize`
 
 error: transmute from a reference to a pointer
-  --> $DIR/transmutes_expressible_as_ptr_casts.rs:65:14
+  --> $DIR/transmutes_expressible_as_ptr_casts.rs:64:14
    |
 LL |     unsafe { transmute::<&[i32; 1], *const u8>(in_param) }
    |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `in_param as *const [i32; 1] as *const u8`

tests/ui/unnecessary_cast_fixable.fixed

@@ -1,7 +1,12 @@
 // run-rustfix
 
 #![warn(clippy::unnecessary_cast)]
-#![allow(clippy::no_effect, clippy::unnecessary_operation, clippy::nonstandard_macro_braces)]
+#![allow(
+    clippy::no_effect,
+    clippy::unnecessary_operation,
+    clippy::nonstandard_macro_braces,
+    clippy::borrow_as_ptr
+)]
 
 fn main() {
     // casting integer literal to float is unnecessary

tests/ui/unnecessary_cast_fixable.rs

@@ -1,7 +1,12 @@
 // run-rustfix
 
 #![warn(clippy::unnecessary_cast)]
-#![allow(clippy::no_effect, clippy::unnecessary_operation, clippy::nonstandard_macro_braces)]
+#![allow(
+    clippy::no_effect,
+    clippy::unnecessary_operation,
+    clippy::nonstandard_macro_braces,
+    clippy::borrow_as_ptr
+)]
 
 fn main() {
     // casting integer literal to float is unnecessary

tests/ui/unnecessary_cast_fixable.stderr

@@ -1,5 +1,5 @@
 error: casting integer literal to `f32` is unnecessary
-  --> $DIR/unnecessary_cast_fixable.rs:8:5
+  --> $DIR/unnecessary_cast_fixable.rs:13:5
    |
 LL |     100 as f32;
    |     ^^^^^^^^^^ help: try: `100_f32`
@@ -7,97 +7,97 @@ LL |     100 as f32;
    = note: `-D clippy::unnecessary-cast` implied by `-D warnings`
 
 error: casting integer literal to `f64` is unnecessary
-  --> $DIR/unnecessary_cast_fixable.rs:9:5
+  --> $DIR/unnecessary_cast_fixable.rs:14:5
    |
 LL |     100 as f64;
    |     ^^^^^^^^^^ help: try: `100_f64`
 
 error: casting integer literal to `f64` is unnecessary
-  --> $DIR/unnecessary_cast_fixable.rs:10:5
+  --> $DIR/unnecessary_cast_fixable.rs:15:5
    |
 LL |     100_i32 as f64;
    |     ^^^^^^^^^^^^^^ help: try: `100_f64`
 
 error: casting integer literal to `f32` is unnecessary
-  --> $DIR/unnecessary_cast_fixable.rs:11:13
+  --> $DIR/unnecessary_cast_fixable.rs:16:13
    |
 LL |     let _ = -100 as f32;
    |             ^^^^^^^^^^^ help: try: `-100_f32`
 
 error: casting integer literal to `f64` is unnecessary
-  --> $DIR/unnecessary_cast_fixable.rs:12:13
+  --> $DIR/unnecessary_cast_fixable.rs:17:13
    |
 LL |     let _ = -100 as f64;
    |             ^^^^^^^^^^^ help: try: `-100_f64`
 
 error: casting integer literal to `f64` is unnecessary
-  --> $DIR/unnecessary_cast_fixable.rs:13:13
+  --> $DIR/unnecessary_cast_fixable.rs:18:13
    |
 LL |     let _ = -100_i32 as f64;
    |             ^^^^^^^^^^^^^^^ help: try: `-100_f64`
 
 error: casting float literal to `f32` is unnecessary
-  --> $DIR/unnecessary_cast_fixable.rs:14:5
+  --> $DIR/unnecessary_cast_fixable.rs:19:5
    |
 LL |     100. as f32;
    |     ^^^^^^^^^^^ help: try: `100_f32`
 
 error: casting float literal to `f64` is unnecessary
-  --> $DIR/unnecessary_cast_fixable.rs:15:5
+  --> $DIR/unnecessary_cast_fixable.rs:20:5
    |
 LL |     100. as f64;
    |     ^^^^^^^^^^^ help: try: `100_f64`
 
 error: casting integer literal to `u32` is unnecessary
-  --> $DIR/unnecessary_cast_fixable.rs:27:5
+  --> $DIR/unnecessary_cast_fixable.rs:32:5
    |
 LL |     1 as u32;
    |     ^^^^^^^^ help: try: `1_u32`
 
 error: casting integer literal to `i32` is unnecessary
-  --> $DIR/unnecessary_cast_fixable.rs:28:5
+  --> $DIR/unnecessary_cast_fixable.rs:33:5
    |
 LL |     0x10 as i32;
    |     ^^^^^^^^^^^ help: try: `0x10_i32`
 
 error: casting integer literal to `usize` is unnecessary
-  --> $DIR/unnecessary_cast_fixable.rs:29:5
+  --> $DIR/unnecessary_cast_fixable.rs:34:5
    |
 LL |     0b10 as usize;
    |     ^^^^^^^^^^^^^ help: try: `0b10_usize`
 
 error: casting integer literal to `u16` is unnecessary
-  --> $DIR/unnecessary_cast_fixable.rs:30:5
+  --> $DIR/unnecessary_cast_fixable.rs:35:5
    |
 LL |     0o73 as u16;
    |     ^^^^^^^^^^^ help: try: `0o73_u16`
 
 error: casting integer literal to `u32` is unnecessary
-  --> $DIR/unnecessary_cast_fixable.rs:31:5
+  --> $DIR/unnecessary_cast_fixable.rs:36:5
    |
 LL |     1_000_000_000 as u32;
    |     ^^^^^^^^^^^^^^^^^^^^ help: try: `1_000_000_000_u32`
 
 error: casting float literal to `f64` is unnecessary
-  --> $DIR/unnecessary_cast_fixable.rs:33:5
+  --> $DIR/unnecessary_cast_fixable.rs:38:5
    |
 LL |     1.0 as f64;
    |     ^^^^^^^^^^ help: try: `1.0_f64`
 
 error: casting float literal to `f32` is unnecessary
-  --> $DIR/unnecessary_cast_fixable.rs:34:5
+  --> $DIR/unnecessary_cast_fixable.rs:39:5
    |
 LL |     0.5 as f32;
    |     ^^^^^^^^^^ help: try: `0.5_f32`
 
 error: casting integer literal to `i32` is unnecessary
-  --> $DIR/unnecessary_cast_fixable.rs:38:13
+  --> $DIR/unnecessary_cast_fixable.rs:43:13
    |
 LL |     let _ = -1 as i32;
    |             ^^^^^^^^^ help: try: `-1_i32`
 
 error: casting float literal to `f32` is unnecessary
-  --> $DIR/unnecessary_cast_fixable.rs:39:13
+  --> $DIR/unnecessary_cast_fixable.rs:44:13
    |
 LL |     let _ = -1.0 as f32;
    |             ^^^^^^^^^^^ help: try: `-1.0_f32`

tests/ui/vtable_address_comparisons.rs

@@ -4,6 +4,8 @@ use std::rc::Rc;
 use std::sync::Arc;
 
 #[warn(clippy::vtable_address_comparisons)]
+#[allow(clippy::borrow_as_ptr)]
+
 fn main() {
     let a: *const dyn Debug = &1 as &dyn Debug;
     let b: *const dyn Debug = &1 as &dyn Debug;

tests/ui/vtable_address_comparisons.stderr

@@ -1,5 +1,5 @@
 error: comparing trait object pointers compares a non-unique vtable address
-  --> $DIR/vtable_address_comparisons.rs:12:13
+  --> $DIR/vtable_address_comparisons.rs:14:13
    |
 LL |     let _ = a == b;
    |             ^^^^^^
@@ -8,7 +8,7 @@ LL |     let _ = a == b;
    = help: consider extracting and comparing data pointers only
 
 error: comparing trait object pointers compares a non-unique vtable address
-  --> $DIR/vtable_address_comparisons.rs:13:13
+  --> $DIR/vtable_address_comparisons.rs:15:13
    |
 LL |     let _ = a != b;
    |             ^^^^^^
@@ -16,7 +16,7 @@ LL |     let _ = a != b;
    = help: consider extracting and comparing data pointers only
 
 error: comparing trait object pointers compares a non-unique vtable address
-  --> $DIR/vtable_address_comparisons.rs:14:13
+  --> $DIR/vtable_address_comparisons.rs:16:13
    |
 LL |     let _ = a < b;
    |             ^^^^^
@@ -24,7 +24,7 @@ LL |     let _ = a < b;
    = help: consider extracting and comparing data pointers only
 
 error: comparing trait object pointers compares a non-unique vtable address
-  --> $DIR/vtable_address_comparisons.rs:15:13
+  --> $DIR/vtable_address_comparisons.rs:17:13
    |
 LL |     let _ = a <= b;
    |             ^^^^^^
@@ -32,7 +32,7 @@ LL |     let _ = a <= b;
    = help: consider extracting and comparing data pointers only
 
 error: comparing trait object pointers compares a non-unique vtable address
-  --> $DIR/vtable_address_comparisons.rs:16:13
+  --> $DIR/vtable_address_comparisons.rs:18:13
    |
 LL |     let _ = a > b;
    |             ^^^^^
@@ -40,7 +40,7 @@ LL |     let _ = a > b;
    = help: consider extracting and comparing data pointers only
 
 error: comparing trait object pointers compares a non-unique vtable address
-  --> $DIR/vtable_address_comparisons.rs:17:13
+  --> $DIR/vtable_address_comparisons.rs:19:13
    |
 LL |     let _ = a >= b;
    |             ^^^^^^
@@ -48,7 +48,7 @@ LL |     let _ = a >= b;
    = help: consider extracting and comparing data pointers only
 
 error: comparing trait object pointers compares a non-unique vtable address
-  --> $DIR/vtable_address_comparisons.rs:18:5
+  --> $DIR/vtable_address_comparisons.rs:20:5
    |
 LL |     ptr::eq(a, b);
    |     ^^^^^^^^^^^^^
@@ -56,7 +56,7 @@ LL |     ptr::eq(a, b);
    = help: consider extracting and comparing data pointers only
 
 error: comparing trait object pointers compares a non-unique vtable address
-  --> $DIR/vtable_address_comparisons.rs:22:5
+  --> $DIR/vtable_address_comparisons.rs:24:5
    |
 LL |     ptr::eq(a, b);
    |     ^^^^^^^^^^^^^
@@ -64,7 +64,7 @@ LL |     ptr::eq(a, b);
    = help: consider extracting and comparing data pointers only
 
 error: comparing trait object pointers compares a non-unique vtable address
-  --> $DIR/vtable_address_comparisons.rs:25:5
+  --> $DIR/vtable_address_comparisons.rs:27:5
    |
 LL |     Rc::ptr_eq(&a, &a);
    |     ^^^^^^^^^^^^^^^^^^
@@ -72,7 +72,7 @@ LL |     Rc::ptr_eq(&a, &a);
    = help: consider extracting and comparing data pointers only
 
 error: comparing trait object pointers compares a non-unique vtable address
-  --> $DIR/vtable_address_comparisons.rs:28:5
+  --> $DIR/vtable_address_comparisons.rs:30:5
    |
 LL |     Arc::ptr_eq(&a, &a);
    |     ^^^^^^^^^^^^^^^^^^^

tests/ui/zero_offset.rs

@@ -1,3 +1,4 @@
+#[allow(clippy::borrow_as_ptr)]
 fn main() {
     unsafe {
         let m = &mut () as *mut ();

tests/ui/zero_offset.stderr

@@ -1,5 +1,5 @@
 error: offset calculation on zero-sized value
-  --> $DIR/zero_offset.rs:4:9
+  --> $DIR/zero_offset.rs:5:9
    |
 LL |         m.offset(0);
    |         ^^^^^^^^^^^
@@ -7,43 +7,43 @@ LL |         m.offset(0);
    = note: `#[deny(clippy::zst_offset)]` on by default
 
 error: offset calculation on zero-sized value
-  --> $DIR/zero_offset.rs:5:9
+  --> $DIR/zero_offset.rs:6:9
    |
 LL |         m.wrapping_add(0);
    |         ^^^^^^^^^^^^^^^^^
 
 error: offset calculation on zero-sized value
-  --> $DIR/zero_offset.rs:6:9
+  --> $DIR/zero_offset.rs:7:9
    |
 LL |         m.sub(0);
    |         ^^^^^^^^
 
 error: offset calculation on zero-sized value
-  --> $DIR/zero_offset.rs:7:9
+  --> $DIR/zero_offset.rs:8:9
    |
 LL |         m.wrapping_sub(0);
    |         ^^^^^^^^^^^^^^^^^
 
 error: offset calculation on zero-sized value
-  --> $DIR/zero_offset.rs:10:9
+  --> $DIR/zero_offset.rs:11:9
    |
 LL |         c.offset(0);
    |         ^^^^^^^^^^^
 
 error: offset calculation on zero-sized value
-  --> $DIR/zero_offset.rs:11:9
+  --> $DIR/zero_offset.rs:12:9
    |
 LL |         c.wrapping_add(0);
    |         ^^^^^^^^^^^^^^^^^
 
 error: offset calculation on zero-sized value
-  --> $DIR/zero_offset.rs:12:9
+  --> $DIR/zero_offset.rs:13:9
    |
 LL |         c.sub(0);
    |         ^^^^^^^^
 
 error: offset calculation on zero-sized value
-  --> $DIR/zero_offset.rs:13:9
+  --> $DIR/zero_offset.rs:14:9
    |
 LL |         c.wrapping_sub(0);
    |         ^^^^^^^^^^^^^^^^^