refactor(allocator): add #[repr(transparent)] to Vec and Box

[overlookmotel]

Both these structs are just wrappers around another type. Best to put #[repr(transparent)] on them.

[overlookmotel]

• refactor(allocator): add #[repr(transparent)] to Vec and Box #13457 👈 (View in Graphite)
• main

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[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #13457 will not alter performance

_{Comparing 08-30-perf_allocator_add_repr_transparent_to_vec_and_box_ (e6cdaa6) with main (68b9b33)¹}

Summary

✅ 37 untouched benchmarks

Footnotes

1. No successful run was found on main (e6cdaa6) during the generation of this report, so 68b9b33 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

[Copilot]

Pull Request Overview

This refactor adds #[repr(transparent)] attributes to the Vec and Box structs in the allocator crate to ensure they have the same memory layout as their wrapped types.

• Adds #[repr(transparent)] to Vec<'alloc, T> wrapper struct
• Adds #[repr(transparent)] to Box<'alloc, T> wrapper struct

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
crates/oxc_allocator/src/vec.rs	Adds transparent representation to Vec wrapper
crates/oxc_allocator/src/boxed.rs	Adds transparent representation to Box wrapper

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[Boshen]

Merge activity

• Aug 31, 6:38 AM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Aug 31, 6:38 AM UTC: Boshen added this pull request to the Graphite merge queue.
• Aug 31, 6:44 AM UTC: Merged by the Graphite merge queue.