…n,Nilstrieb

Fix deallocation with wrong allocator in (A)Rc::from_box_in

Deallocate the `Box` with the original allocator (via `&A`), not `Global`.

Fixes rust-lang#119749

<details> <summary>Example code with error and Miri output</summary>

(Note that this UB is not observable on stable, because the only usable allocator on stable is `Global` anyway.)

Code ([playground link](https://play.rust-lang.org/?version=nightly&mode=debug&edition=2021&gist=96193c2c6a1912d7f669fbbe39174b09)):

```rs
#![feature(allocator_api)]
use std::alloc::System;

// uncomment one of these
use std::rc::Rc;
//use std::sync::Arc as Rc;

fn main() {
    let x: Box<[u32], System> = Box::new_in([1,2,3], System);
    let _: Rc<[u32], System> = Rc::from(x);
}
```

Miri output:

```rs
error: Undefined Behavior: deallocating alloc904, which is C heap memory, using Rust heap deallocation operation
   --> /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/alloc.rs:117:14
    |
117 |     unsafe { __rust_dealloc(ptr, layout.size(), layout.align()) }
    |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ deallocating alloc904, which is C heap memory, using Rust heap deallocation operation
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
    = note: BACKTRACE:
    = note: inside `std::alloc::dealloc` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/alloc.rs:117:14: 117:64
    = note: inside `<std::alloc::Global as std::alloc::Allocator>::deallocate` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/alloc.rs:254:22: 254:51
    = note: inside `<std::boxed::Box<std::mem::ManuallyDrop<[u32]>> as std::ops::Drop>::drop` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/boxed.rs:1244:17: 1244:66
    = note: inside `std::ptr::drop_in_place::<std::boxed::Box<std::mem::ManuallyDrop<[u32]>>> - shim(Some(std::boxed::Box<std::mem::ManuallyDrop<[u32]>>))` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/ptr/mod.rs:507:1: 507:56
    = note: inside `std::mem::drop::<std::boxed::Box<std::mem::ManuallyDrop<[u32]>>>` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/mem/mod.rs:992:24: 992:25
    = note: inside `std::rc::Rc::<[u32], std::alloc::System>::from_box_in` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/rc.rs:1928:13: 1928:22
    = note: inside `<std::rc::Rc<[u32], std::alloc::System> as std::convert::From<std::boxed::Box<[u32], std::alloc::System>>>::from` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/rc.rs:2504:9: 2504:27
note: inside `main`
   --> src/main.rs:10:32
    |
10  |     let _: Rc<[u32], System> = Rc::from(x);
    |                                ^^^^^^^^^^^

note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace

error: aborting due to 1 previous error
```

</details>

Rollup of 12 pull requests

Successful merges:

 - rust-lang#118639 (Undeprecate lint `unstable_features` and make use of it in the compiler)
 - rust-lang#118714 ( Explanation that fields are being used when deriving `(Partial)Ord` on enums)
 - rust-lang#119801 (Fix deallocation with wrong allocator in (A)Rc::from_box_in)
 - rust-lang#119948 (Make `unsafe_op_in_unsafe_fn` migrated in edition 2024)
 - rust-lang#119999 (remote-test: use u64 to represent file size)
 - rust-lang#120058 (bootstrap: improvements for compiler builds)
 - rust-lang#120160 (Manually implement derived `NonZero` traits.)
 - rust-lang#120177 (Remove duplicate dependencies for rustc)
 - rust-lang#120185 (coverage: Don't instrument `#[automatically_derived]` functions)
 - rust-lang#120194 (Shorten `#[must_use]` Diagnostic Message for `Option::is_none`)
 - rust-lang#120200 (Correct the anchor of an URL in an error message)
 - rust-lang#120203 (Replace `#!/bin/bash` with `#!/usr/bin/env bash` in rust-installer tests)

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

…n,Nilstrieb

Fix deallocation with wrong allocator in (A)Rc::from_box_in

Deallocate the `Box` with the original allocator (via `&A`), not `Global`.

Fixes rust-lang#119749

<details> <summary>Example code with error and Miri output</summary>

(Note that this UB is not observable on stable, because the only usable allocator on stable is `Global` anyway.)

Code ([playground link](https://play.rust-lang.org/?version=nightly&mode=debug&edition=2021&gist=96193c2c6a1912d7f669fbbe39174b09)):

```rs
#![feature(allocator_api)]
use std::alloc::System;

// uncomment one of these
use std::rc::Rc;
//use std::sync::Arc as Rc;

fn main() {
    let x: Box<[u32], System> = Box::new_in([1,2,3], System);
    let _: Rc<[u32], System> = Rc::from(x);
}
```

Miri output:

```rs
error: Undefined Behavior: deallocating alloc904, which is C heap memory, using Rust heap deallocation operation
   --> /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/alloc.rs:117:14
    |
117 |     unsafe { __rust_dealloc(ptr, layout.size(), layout.align()) }
    |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ deallocating alloc904, which is C heap memory, using Rust heap deallocation operation
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
    = note: BACKTRACE:
    = note: inside `std::alloc::dealloc` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/alloc.rs:117:14: 117:64
    = note: inside `<std::alloc::Global as std::alloc::Allocator>::deallocate` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/alloc.rs:254:22: 254:51
    = note: inside `<std::boxed::Box<std::mem::ManuallyDrop<[u32]>> as std::ops::Drop>::drop` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/boxed.rs:1244:17: 1244:66
    = note: inside `std::ptr::drop_in_place::<std::boxed::Box<std::mem::ManuallyDrop<[u32]>>> - shim(Some(std::boxed::Box<std::mem::ManuallyDrop<[u32]>>))` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/ptr/mod.rs:507:1: 507:56
    = note: inside `std::mem::drop::<std::boxed::Box<std::mem::ManuallyDrop<[u32]>>>` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/mem/mod.rs:992:24: 992:25
    = note: inside `std::rc::Rc::<[u32], std::alloc::System>::from_box_in` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/rc.rs:1928:13: 1928:22
    = note: inside `<std::rc::Rc<[u32], std::alloc::System> as std::convert::From<std::boxed::Box<[u32], std::alloc::System>>>::from` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/rc.rs:2504:9: 2504:27
note: inside `main`
   --> src/main.rs:10:32
    |
10  |     let _: Rc<[u32], System> = Rc::from(x);
    |                                ^^^^^^^^^^^

note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace

error: aborting due to 1 previous error
```

</details>

…n,Nilstrieb

Fix deallocation with wrong allocator in (A)Rc::from_box_in

Deallocate the `Box` with the original allocator (via `&A`), not `Global`.

Fixes rust-lang#119749

<details> <summary>Example code with error and Miri output</summary>

(Note that this UB is not observable on stable, because the only usable allocator on stable is `Global` anyway.)

Code ([playground link](https://play.rust-lang.org/?version=nightly&mode=debug&edition=2021&gist=96193c2c6a1912d7f669fbbe39174b09)):

```rs
#![feature(allocator_api)]
use std::alloc::System;

// uncomment one of these
use std::rc::Rc;
//use std::sync::Arc as Rc;

fn main() {
    let x: Box<[u32], System> = Box::new_in([1,2,3], System);
    let _: Rc<[u32], System> = Rc::from(x);
}
```

Miri output:

```rs
error: Undefined Behavior: deallocating alloc904, which is C heap memory, using Rust heap deallocation operation
   --> /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/alloc.rs:117:14
    |
117 |     unsafe { __rust_dealloc(ptr, layout.size(), layout.align()) }
    |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ deallocating alloc904, which is C heap memory, using Rust heap deallocation operation
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
    = note: BACKTRACE:
    = note: inside `std::alloc::dealloc` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/alloc.rs:117:14: 117:64
    = note: inside `<std::alloc::Global as std::alloc::Allocator>::deallocate` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/alloc.rs:254:22: 254:51
    = note: inside `<std::boxed::Box<std::mem::ManuallyDrop<[u32]>> as std::ops::Drop>::drop` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/boxed.rs:1244:17: 1244:66
    = note: inside `std::ptr::drop_in_place::<std::boxed::Box<std::mem::ManuallyDrop<[u32]>>> - shim(Some(std::boxed::Box<std::mem::ManuallyDrop<[u32]>>))` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/ptr/mod.rs:507:1: 507:56
    = note: inside `std::mem::drop::<std::boxed::Box<std::mem::ManuallyDrop<[u32]>>>` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/mem/mod.rs:992:24: 992:25
    = note: inside `std::rc::Rc::<[u32], std::alloc::System>::from_box_in` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/rc.rs:1928:13: 1928:22
    = note: inside `<std::rc::Rc<[u32], std::alloc::System> as std::convert::From<std::boxed::Box<[u32], std::alloc::System>>>::from` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/rc.rs:2504:9: 2504:27
note: inside `main`
   --> src/main.rs:10:32
    |
10  |     let _: Rc<[u32], System> = Rc::from(x);
    |                                ^^^^^^^^^^^

note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace

error: aborting due to 1 previous error
```

</details>

…iaskrgr

Rollup of 11 pull requests

Successful merges:

 - rust-lang#117910 (Refactor uses of `objc_msgSend` to no longer have clashing definitions)
 - rust-lang#118639 (Undeprecate lint `unstable_features` and make use of it in the compiler)
 - rust-lang#119801 (Fix deallocation with wrong allocator in (A)Rc::from_box_in)
 - rust-lang#120058 (bootstrap: improvements for compiler builds)
 - rust-lang#120059 (Make generic const type mismatches not hide trait impls from the trait solver)
 - rust-lang#120097 (Report unreachable subpatterns consistently)
 - rust-lang#120137 (Validate AggregateKind types in MIR)
 - rust-lang#120164 (`maybe_lint_impl_trait`: separate `is_downgradable` from `is_object_safe`)
 - rust-lang#120181 (Allow any `const` expression blocks in `thread_local!`)
 - rust-lang#120204 (Builtin macros effectively have implicit #[collapse_debuginfo(yes)])
 - rust-lang#120218 (rustfmt: Check that a token can begin a nonterminal kind before parsing it as a macro arg)

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

…iaskrgr

Rollup of 10 pull requests

Successful merges:

 - rust-lang#117910 (Refactor uses of `objc_msgSend` to no longer have clashing definitions)
 - rust-lang#118639 (Undeprecate lint `unstable_features` and make use of it in the compiler)
 - rust-lang#119801 (Fix deallocation with wrong allocator in (A)Rc::from_box_in)
 - rust-lang#120058 (bootstrap: improvements for compiler builds)
 - rust-lang#120059 (Make generic const type mismatches not hide trait impls from the trait solver)
 - rust-lang#120097 (Report unreachable subpatterns consistently)
 - rust-lang#120137 (Validate AggregateKind types in MIR)
 - rust-lang#120164 (`maybe_lint_impl_trait`: separate `is_downgradable` from `is_object_safe`)
 - rust-lang#120181 (Allow any `const` expression blocks in `thread_local!`)
 - rust-lang#120218 (rustfmt: Check that a token can begin a nonterminal kind before parsing it as a macro arg)

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

Rollup merge of rust-lang#119801 - zachs18:zachs18-patch-1, r=steffahn,Nilstrieb

Fix deallocation with wrong allocator in (A)Rc::from_box_in

Deallocate the `Box` with the original allocator (via `&A`), not `Global`.

Fixes rust-lang#119749

<details> <summary>Example code with error and Miri output</summary>

(Note that this UB is not observable on stable, because the only usable allocator on stable is `Global` anyway.)

Code ([playground link](https://play.rust-lang.org/?version=nightly&mode=debug&edition=2021&gist=96193c2c6a1912d7f669fbbe39174b09)):

```rs
#![feature(allocator_api)]
use std::alloc::System;

// uncomment one of these
use std::rc::Rc;
//use std::sync::Arc as Rc;

fn main() {
    let x: Box<[u32], System> = Box::new_in([1,2,3], System);
    let _: Rc<[u32], System> = Rc::from(x);
}
```

Miri output:

```rs
error: Undefined Behavior: deallocating alloc904, which is C heap memory, using Rust heap deallocation operation
   --> /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/alloc.rs:117:14
    |
117 |     unsafe { __rust_dealloc(ptr, layout.size(), layout.align()) }
    |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ deallocating alloc904, which is C heap memory, using Rust heap deallocation operation
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
    = note: BACKTRACE:
    = note: inside `std::alloc::dealloc` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/alloc.rs:117:14: 117:64
    = note: inside `<std::alloc::Global as std::alloc::Allocator>::deallocate` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/alloc.rs:254:22: 254:51
    = note: inside `<std::boxed::Box<std::mem::ManuallyDrop<[u32]>> as std::ops::Drop>::drop` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/boxed.rs:1244:17: 1244:66
    = note: inside `std::ptr::drop_in_place::<std::boxed::Box<std::mem::ManuallyDrop<[u32]>>> - shim(Some(std::boxed::Box<std::mem::ManuallyDrop<[u32]>>))` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/ptr/mod.rs:507:1: 507:56
    = note: inside `std::mem::drop::<std::boxed::Box<std::mem::ManuallyDrop<[u32]>>>` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/mem/mod.rs:992:24: 992:25
    = note: inside `std::rc::Rc::<[u32], std::alloc::System>::from_box_in` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/rc.rs:1928:13: 1928:22
    = note: inside `<std::rc::Rc<[u32], std::alloc::System> as std::convert::From<std::boxed::Box<[u32], std::alloc::System>>>::from` at /playground/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/rc.rs:2504:9: 2504:27
note: inside `main`
   --> src/main.rs:10:32
    |
10  |     let _: Rc<[u32], System> = Rc::from(x);
    |                                ^^^^^^^^^^^

note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace

error: aborting due to 1 previous error
```

</details>