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Merged
merged 1 commit into from
Sep 28, 2025
Merged

Allow &raw [mut | const] for union field in safe code #141469

merged 1 commit into from
Sep 28, 2025
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@Kivooeo
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@Kivooeo Kivooeo commented May 23, 2025 •
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fixes #141264

r? @Veykril

Unresolved questions:

  • Any edge cases?
  • How this works with rust-analyzer (because all I've did is prevent compiler from emitting error in &raw context) (Allow &raw [mut | const] for union field  rust-analyzer#19867)
  • Should we allow addr_of! and addr_of_mut! as well? In current version they both (&raw and addr_of!) are allowed (They are the same)
  • Is chain of union fields is a safe? (Yes)

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rustbot commented May 23, 2025

Failed to set assignee to Veykril: invalid assignee

Note: Only org members with at least the repository "read" role, users with write permissions, or people who have commented on the PR may be assigned.

@rustbot rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. labels May 23, 2025
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jieyouxu commented May 23, 2025

cc @RalfJung

@fmease fmease added the I-lang-nominated Nominated for discussion during a lang team meeting. label May 23, 2025
@Kivooeo Kivooeo changed the title Allow &raw [mut | const] for union field in safe Allow &raw [mut | const] for union field in safe May 23, 2025
@fmease fmease added the needs-fcp This change is insta-stable, or significant enough to need a team FCP to proceed. label May 23, 2025
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RalfJung commented May 23, 2025

Uh, the unsafety checker is not actually code I know very well, sorry.
r? compiler

@rustbot rustbot assigned davidtwco and unassigned RalfJung May 23, 2025
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RalfJung commented May 23, 2025

Should we allow addr_of! and addr_of_mut! as well? In current version they both (&raw and addr_of!) are allowed

The macros just expand to &raw, it's not even possible to treat them differently.

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Kivooeo commented May 23, 2025

I will debug this later today but this is very weird

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@fmease fmease added T-lang Relevant to the language team S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. and removed I-lang-nominated Nominated for discussion during a lang team meeting. S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels May 24, 2025
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@Kivooeo Kivooeo force-pushed the remove-usnsafegate branch from b006128 to 43892d3 Compare May 24, 2025 11:46
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@Kivooeo Kivooeo force-pushed the remove-usnsafegate branch from b60d3ff to fc03435 Compare May 24, 2025 12:03
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@Kivooeo Kivooeo force-pushed the remove-usnsafegate branch from 9ccf35d to cde9fa0 Compare May 24, 2025 12:48
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Kivooeo commented May 24, 2025

@rustbot ready

@rustbot rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. and removed S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. labels May 24, 2025
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rust-rfcbot commented Sep 10, 2025

🔔 This is now entering its final comment period, as per the review above. 🔔

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nikomatsakis commented Sep 10, 2025

@rfcbot reviewed

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compiler-errors commented Sep 14, 2025

r=me when FCP is over.

@traviscross traviscross added I-lang-radar Items that are on lang's radar and will need eventual work or consideration. and removed I-lang-nominated Nominated for discussion during a lang team meeting. P-lang-drag-1 Lang team prioritization drag level 1. https://rust-lang.zulipchat.com/#narrow/channel/410516-t-lang labels Sep 15, 2025
@rust-rfcbot rust-rfcbot added finished-final-comment-period The final comment period is finished for this PR / Issue. and removed final-comment-period In the final comment period and will be merged soon unless new substantive objections are raised. labels Sep 20, 2025
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rust-rfcbot commented Sep 20, 2025

The final comment period, with a disposition to merge, as per the review above, is now complete.

As the automated representative of the governance process, I would like to thank the author for their work and everyone else who contributed.

This will be merged soon.

@rust-rfcbot rust-rfcbot added the to-announce Announce this issue on triage meeting label Sep 20, 2025
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@traviscross traviscross added the relnotes Marks issues that should be documented in the release notes of the next release. label Sep 21, 2025
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jdonszelmann commented Sep 28, 2025

@bors r=compiler-errors

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bors commented Sep 28, 2025

📌 Commit 23f1767 has been approved by compiler-errors

It is now in the queue for this repository.

@bors bors added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. S-waiting-on-team DEPRECATED: Use the team-based variants `S-waiting-on-t-lang`, `S-waiting-on-t-compiler`, ... labels Sep 28, 2025
matthiaskrgr added a commit to matthiaskrgr/rust that referenced this pull request Sep 28, 2025
@matthiaskrgr
Rollup merge of rust-lang#141469 - Kivooeo:remove-usnsafegate, r=comp…
2d7f221 
…iler-errors

Allow `&raw [mut | const]` for union field in safe code

fixes rust-lang#141264

r? `@Veykril`

Unresolved questions:

- [x] Any edge cases?
- [x] How this works with rust-analyzer (because all I've did is prevent compiler from emitting error in `&raw` context) (rust-lang/rust-analyzer#19867)
- [x] Should we allow `addr_of!` and `addr_of_mut!` as well? In current version they both (`&raw` and `addr_of!`) are allowed (They are the same)
- [x] Is chain of union fields is a safe? (Yes)
@matthiaskrgr matthiaskrgr mentioned this pull request Sep 28, 2025
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bors added a commit that referenced this pull request Sep 28, 2025
@bors
Auto merge of #147128 - matthiaskrgr:rollup-mqey4c4, r=matthiaskrgr
c8905ea 
Rollup of 6 pull requests

Successful merges:

 - #140482 (std::net: update tcp deferaccept delay type to Duration.)
 - #141469 (Allow `&raw [mut | const]` for union field in safe code)
 - #144197 (TypeTree support in autodiff)
 - #146675 (Allow shared access to `Exclusive<T>` when `T: Sync`)
 - #147113 (Reland "Add LSX accelerated implementation for source file analysis")
 - #147120 (Fix --extra-checks=spellcheck to prevent cargo install every time)

r? `@ghost`
`@rustbot` modify labels: rollup
@bors bors merged commit 6059195 into rust-lang:master Sep 28, 2025
10 checks passed
@rustbot rustbot added this to the 1.92.0 milestone Sep 28, 2025
rust-timer added a commit that referenced this pull request Sep 28, 2025
@rust-timer
Unrolled build for #141469
be75a93 
Rollup merge of #141469 - Kivooeo:remove-usnsafegate, r=compiler-errors

Allow `&raw [mut | const]` for union field in safe code

fixes #141264

r? ``@Veykril``

Unresolved questions:

- [x] Any edge cases?
- [x] How this works with rust-analyzer (because all I've did is prevent compiler from emitting error in `&raw` context) (rust-lang/rust-analyzer#19867)
- [x] Should we allow `addr_of!` and `addr_of_mut!` as well? In current version they both (`&raw` and `addr_of!`) are allowed (They are the same)
- [x] Is chain of union fields is a safe? (Yes)
github-actions bot pushed a commit to rust-lang/miri that referenced this pull request Sep 29, 2025
@bors
Auto merge of #147128 - matthiaskrgr:rollup-mqey4c4, r=matthiaskrgr
378536f 
Rollup of 6 pull requests

Successful merges:

 - rust-lang/rust#140482 (std::net: update tcp deferaccept delay type to Duration.)
 - rust-lang/rust#141469 (Allow `&raw [mut | const]` for union field in safe code)
 - rust-lang/rust#144197 (TypeTree support in autodiff)
 - rust-lang/rust#146675 (Allow shared access to `Exclusive<T>` when `T: Sync`)
 - rust-lang/rust#147113 (Reland "Add LSX accelerated implementation for source file analysis")
 - rust-lang/rust#147120 (Fix --extra-checks=spellcheck to prevent cargo install every time)

r? `@ghost`
`@rustbot` modify labels: rollup
intel-lab-lkp pushed a commit to intel-lab-lkp/linux that referenced this pull request Oct 13, 2025
@ojeda @intel-lab-lkp
rust: bitmap: clean Rust 1.92.0 unused_unsafe warning
37c2ee8 
Starting with Rust 1.92.0 (expected 2025-12-11), Rust allows to safely
take the address of a union field [1][2]:

      CLIPPY L rust/kernel.o
    error: unnecessary `unsafe` block
       --> rust/kernel/bitmap.rs:169:13
        |
    169 |             unsafe { core::ptr::addr_of!(self.repr.bitmap) }
        |             ^^^^^^ unnecessary `unsafe` block
        |
        = note: `-D unused-unsafe` implied by `-D warnings`
        = help: to override `-D warnings` add `#[allow(unused_unsafe)]`

    error: unnecessary `unsafe` block
       --> rust/kernel/bitmap.rs:185:13
        |
    185 |             unsafe { core::ptr::addr_of_mut!(self.repr.bitmap) }
        |             ^^^^^^ unnecessary `unsafe` block

Thus allow both instances to clean the warning in newer compilers.

Link: rust-lang/rust#141264 [1]
Link: rust-lang/rust#141469 [2]
Signed-off-by: Miguel Ojeda <[email protected]>
mj22226 pushed a commit to mj22226/linux that referenced this pull request Oct 15, 2025
@ojeda @YuryNorov
rust: bitmap: clean Rust 1.92.0 unused_unsafe warning
8169e48 
Starting with Rust 1.92.0 (expected 2025-12-11), Rust allows to safely
take the address of a union field [1][2]:

      CLIPPY L rust/kernel.o
    error: unnecessary `unsafe` block
       --> rust/kernel/bitmap.rs:169:13
        |
    169 |             unsafe { core::ptr::addr_of!(self.repr.bitmap) }
        |             ^^^^^^ unnecessary `unsafe` block
        |
        = note: `-D unused-unsafe` implied by `-D warnings`
        = help: to override `-D warnings` add `#[allow(unused_unsafe)]`

    error: unnecessary `unsafe` block
       --> rust/kernel/bitmap.rs:185:13
        |
    185 |             unsafe { core::ptr::addr_of_mut!(self.repr.bitmap) }
        |             ^^^^^^ unnecessary `unsafe` block

Thus allow both instances to clean the warning in newer compilers.

Link: rust-lang/rust#141264 [1]
Link: rust-lang/rust#141469 [2]
Signed-off-by: Miguel Ojeda <[email protected]>
Reviewed-by: Alice Ryhl <[email protected]>
Signed-off-by: Yury Norov (NVIDIA) <[email protected]>
norov pushed a commit to norov/linux that referenced this pull request Oct 15, 2025
@ojeda @YuryNorov
rust: bitmap: clean Rust 1.92.0 unused_unsafe warning
0f58788 
Starting with Rust 1.92.0 (expected 2025-12-11), Rust allows to safely
take the address of a union field [1][2]:

      CLIPPY L rust/kernel.o
    error: unnecessary `unsafe` block
       --> rust/kernel/bitmap.rs:169:13
        |
    169 |             unsafe { core::ptr::addr_of!(self.repr.bitmap) }
        |             ^^^^^^ unnecessary `unsafe` block
        |
        = note: `-D unused-unsafe` implied by `-D warnings`
        = help: to override `-D warnings` add `#[allow(unused_unsafe)]`

    error: unnecessary `unsafe` block
       --> rust/kernel/bitmap.rs:185:13
        |
    185 |             unsafe { core::ptr::addr_of_mut!(self.repr.bitmap) }
        |             ^^^^^^ unnecessary `unsafe` block

Thus allow both instances to clean the warning in newer compilers.

Link: rust-lang/rust#141264 [1]
Link: rust-lang/rust#141469 [2]
Signed-off-by: Miguel Ojeda <[email protected]>
Reviewed-by: Alice Ryhl <[email protected]>
Signed-off-by: Yury Norov (NVIDIA) <[email protected]>
riteshharjani pushed a commit to riteshharjani/linux-ci that referenced this pull request Oct 29, 2025
@ojeda @riteshharjani
rust: bitmap: clean Rust 1.92.0 unused_unsafe warning
30de677 
Starting with Rust 1.92.0 (expected 2025-12-11), Rust allows to safely
take the address of a union field [1][2]:

      CLIPPY L rust/kernel.o
    error: unnecessary `unsafe` block
       --> rust/kernel/bitmap.rs:169:13
        |
    169 |             unsafe { core::ptr::addr_of!(self.repr.bitmap) }
        |             ^^^^^^ unnecessary `unsafe` block
        |
        = note: `-D unused-unsafe` implied by `-D warnings`
        = help: to override `-D warnings` add `#[allow(unused_unsafe)]`

    error: unnecessary `unsafe` block
       --> rust/kernel/bitmap.rs:185:13
        |
    185 |             unsafe { core::ptr::addr_of_mut!(self.repr.bitmap) }
        |             ^^^^^^ unnecessary `unsafe` block

Thus allow both instances to clean the warning in newer compilers.

Link: rust-lang/rust#141264 [1]
Link: rust-lang/rust#141469 [2]
Signed-off-by: Miguel Ojeda <[email protected]>
Reviewed-by: Alice Ryhl <[email protected]>
Signed-off-by: Yury Norov (NVIDIA) <[email protected]>
@cuviper cuviper mentioned this pull request Nov 20, 2025
Open
@apiraino apiraino removed the to-announce Announce this issue on triage meeting label Nov 27, 2025
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&raw const some_union.field erroneously requires unsafe