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Ensure correct aligement of rustc_hir::Lifetime on platforms with lower default alignments. #144578

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merged 1 commit into from
Jul 29, 2025

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FractalFir
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The compiler relies on hir::Lifetime being aligned to at least 4 bytes(for the purposes of pointer tagging).

However, on some systems(like m68k) with lower alignment requirements(eg. usize / u32 aligned to 2 bytes),hir::Lifetime will be aligned to only 2 bytes.

This causes the compilation to fail on those systems - a const assert in the compiler fails.

This PR makes the aligement requriement of hir::Lifetime explict. This has no effect on platforms where that already is the case(repr align can only raise alignment), but ensures the alignment will stay correct no matter what.

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rustbot commented Jul 28, 2025

r? @davidtwco

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@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 Jul 28, 2025
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@bors r+ rollup

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bors commented Jul 28, 2025

📌 Commit 72927f6 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. labels Jul 28, 2025
samueltardieu added a commit to samueltardieu/rust that referenced this pull request Jul 28, 2025
…rors

Ensure correct aligement of rustc_hir::Lifetime on platforms with lower default alignments.

The compiler relies on `hir::Lifetime` being aligned to at least 4 bytes(for the purposes of pointer tagging).

However, on some systems(like m68k) with lower alignment requirements(eg. usize / u32 aligned to 2 bytes),`hir::Lifetime` will be aligned to only 2 bytes.

This causes the compilation to fail on those systems - a const assert in the compiler fails.

This PR makes the aligement requriement of hir::Lifetime explict. This has no effect on platforms where that already is the case(repr align can only raise alignment), but ensures the alignment will stay correct no matter what.
bors added a commit that referenced this pull request Jul 29, 2025
Rollup of 11 pull requests

Successful merges:

 - #143289 (Remove `[T]::array_chunks(_mut)`)
 - #143883 (Add `--link-targets-dir` argument to linkchecker)
 - #144034 (tests: Test line number in debuginfo for diverging function calls)
 - #144236 (Add `core::mem::DropGuard`)
 - #144268 (Add method `find_ancestor_not_from_macro` and `find_ancestor_not_from_extern_macro` to supersede `find_oldest_ancestor_in_same_ctxt`)
 - #144303 (Consolidate staging for `rustc_private` tools)
 - #144539 (constify with_exposed_provenance)
 - #144569 (rustc-dev-guide subtree update)
 - #144573 (Raw Pointers are Constant PatKinds too)
 - #144578 (Ensure correct aligement of rustc_hir::Lifetime on platforms with lower default alignments.)
 - #144582 (fix `Atomic*::as_ptr` wording)

r? `@ghost`
`@rustbot` modify labels: rollup
Zalathar added a commit to Zalathar/rust that referenced this pull request Jul 29, 2025
…rors

Ensure correct aligement of rustc_hir::Lifetime on platforms with lower default alignments.

The compiler relies on `hir::Lifetime` being aligned to at least 4 bytes(for the purposes of pointer tagging).

However, on some systems(like m68k) with lower alignment requirements(eg. usize / u32 aligned to 2 bytes),`hir::Lifetime` will be aligned to only 2 bytes.

This causes the compilation to fail on those systems - a const assert in the compiler fails.

This PR makes the aligement requriement of hir::Lifetime explict. This has no effect on platforms where that already is the case(repr align can only raise alignment), but ensures the alignment will stay correct no matter what.
Zalathar added a commit to Zalathar/rust that referenced this pull request Jul 29, 2025
…rors

Ensure correct aligement of rustc_hir::Lifetime on platforms with lower default alignments.

The compiler relies on `hir::Lifetime` being aligned to at least 4 bytes(for the purposes of pointer tagging).

However, on some systems(like m68k) with lower alignment requirements(eg. usize / u32 aligned to 2 bytes),`hir::Lifetime` will be aligned to only 2 bytes.

This causes the compilation to fail on those systems - a const assert in the compiler fails.

This PR makes the aligement requriement of hir::Lifetime explict. This has no effect on platforms where that already is the case(repr align can only raise alignment), but ensures the alignment will stay correct no matter what.
Zalathar added a commit to Zalathar/rust that referenced this pull request Jul 29, 2025
…rors

Ensure correct aligement of rustc_hir::Lifetime on platforms with lower default alignments.

The compiler relies on `hir::Lifetime` being aligned to at least 4 bytes(for the purposes of pointer tagging).

However, on some systems(like m68k) with lower alignment requirements(eg. usize / u32 aligned to 2 bytes),`hir::Lifetime` will be aligned to only 2 bytes.

This causes the compilation to fail on those systems - a const assert in the compiler fails.

This PR makes the aligement requriement of hir::Lifetime explict. This has no effect on platforms where that already is the case(repr align can only raise alignment), but ensures the alignment will stay correct no matter what.
bors added a commit that referenced this pull request Jul 29, 2025
Rollup of 11 pull requests

Successful merges:

 - #143883 (Add `--link-targets-dir` argument to linkchecker)
 - #144236 (Add `core::mem::DropGuard`)
 - #144303 (Consolidate staging for `rustc_private` tools)
 - #144367 (Move dist-apple-various from x86_64 to aarch64)
 - #144539 (constify with_exposed_provenance)
 - #144569 (rustc-dev-guide subtree update)
 - #144573 (Raw Pointers are Constant PatKinds too)
 - #144575 (fixed typo chunks->as_chunks)
 - #144578 (Ensure correct aligement of rustc_hir::Lifetime on platforms with lower default alignments.)
 - #144582 (fix `Atomic*::as_ptr` wording)
 - #144616 (coverage: Regression test for "function name is empty" bug)

r? `@ghost`
`@rustbot` modify labels: rollup
bors added a commit that referenced this pull request Jul 29, 2025
Rollup of 10 pull requests

Successful merges:

 - #143883 (Add `--link-targets-dir` argument to linkchecker)
 - #144236 (Add `core::mem::DropGuard`)
 - #144367 (Move dist-apple-various from x86_64 to aarch64)
 - #144539 (constify with_exposed_provenance)
 - #144569 (rustc-dev-guide subtree update)
 - #144573 (Raw Pointers are Constant PatKinds too)
 - #144575 (fixed typo chunks->as_chunks)
 - #144578 (Ensure correct aligement of rustc_hir::Lifetime on platforms with lower default alignments.)
 - #144582 (fix `Atomic*::as_ptr` wording)
 - #144616 (coverage: Regression test for "function name is empty" bug)

r? `@ghost`
`@rustbot` modify labels: rollup
@bors bors merged commit e08a308 into rust-lang:master Jul 29, 2025
10 checks passed
@rustbot rustbot added this to the 1.90.0 milestone Jul 29, 2025
rust-timer added a commit that referenced this pull request Jul 29, 2025
Rollup merge of #144578 - FractalFir:m68k_fix, r=compiler-errors

Ensure correct aligement of rustc_hir::Lifetime on platforms with lower default alignments.

The compiler relies on `hir::Lifetime` being aligned to at least 4 bytes(for the purposes of pointer tagging).

However, on some systems(like m68k) with lower alignment requirements(eg. usize / u32 aligned to 2 bytes),`hir::Lifetime` will be aligned to only 2 bytes.

This causes the compilation to fail on those systems - a const assert in the compiler fails.

This PR makes the aligement requriement of hir::Lifetime explict. This has no effect on platforms where that already is the case(repr align can only raise alignment), but ensures the alignment will stay correct no matter what.
github-actions bot pushed a commit to rust-lang/rustc-dev-guide that referenced this pull request Jul 31, 2025
Rollup of 10 pull requests

Successful merges:

 - rust-lang/rust#143883 (Add `--link-targets-dir` argument to linkchecker)
 - rust-lang/rust#144236 (Add `core::mem::DropGuard`)
 - rust-lang/rust#144367 (Move dist-apple-various from x86_64 to aarch64)
 - rust-lang/rust#144539 (constify with_exposed_provenance)
 - rust-lang/rust#144569 (rustc-dev-guide subtree update)
 - rust-lang/rust#144573 (Raw Pointers are Constant PatKinds too)
 - rust-lang/rust#144575 (fixed typo chunks->as_chunks)
 - rust-lang/rust#144578 (Ensure correct aligement of rustc_hir::Lifetime on platforms with lower default alignments.)
 - rust-lang/rust#144582 (fix `Atomic*::as_ptr` wording)
 - rust-lang/rust#144616 (coverage: Regression test for "function name is empty" bug)

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