refactor(allocator): fix borrow_as_ptr clippy warnings

[overlookmotel]

Continuation of #21210.

Use NonNull::from_ref to construct self-pointing pointers in EMPTY_CHUNK. This removes some unsafe code.

[overlookmotel]

• docs(allocator): add doc comments for panics and errors #21230
• refactor(allocator): fix unnecessary_safety_comment clippy warnings #21229
• refactor(allocator): fix unsafe_op_in_unsafe_fn clippy warnings #21228
• refactor(allocator): fix mut_from_ref clippy warnings #21225
• refactor(allocator): fix cast_sign_loss clippy warnings #21224
• refactor(allocator): fix cast_ptr_alignment clippy warnings #21223
• refactor(allocator): fix ptr_cast_constness clippy warnings #21222
• refactor(allocator): fix ptr_as_ptr clippy warnings #21221
• refactor(allocator): fix ref_as_ptr clippy warnings #21220
• refactor(allocator): fix borrow_as_ptr clippy warnings #21219 👈 (View in Graphite)
• refactor(allocator): fix unused_self clippy warnings #21218
• refactor(allocator): fix manual_div_ceil clippy warnings #21217
• refactor(allocator): fix map_unwrap_or clippy warnings #21216
• refactor(allocator): fix filter_map_next clippy warnings #21215
• refactor(allocator): fix single_match_else clippy warnings #21214
• refactor(allocator): fix inconsistent_struct_constructor clippy warnings #21213
• refactor(allocator): fix semicolon_if_nothing_returned clippy warnings #21212
• refactor(allocator): fix uninlined_format_args clippy warnings #21211
• refactor(allocator): fix lifetimes clippy warnings #21210
• main

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[codspeed-hq]

Merging this PR will not alter performance

✅ 48 untouched benchmarks
⏩ 3 skipped benchmarks¹

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_{Comparing om/04-08-refactor_allocator_fix_borrow_as_ptr_clippy_warnings (87fef2d) with om/04-08-refactor_allocator_fix_unused_self_clippy_warnings (137fa5f)}

Footnotes

1. 3 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[Copilot]

Pull request overview

This PR continues the allocator refactor by removing clippy::borrow_as_ptr suppression and replacing manual pointer casts/unsafe NonNull::new_unchecked usage in the canonical EMPTY_CHUNK sentinel with NonNull::from_ref, reducing unsafe surface area in the bump allocator implementation.

Changes:

• Removed the clippy::borrow_as_ptr #![expect(...)] entry from bump.rs.
• Refactored EMPTY_CHUNK self-referential pointers (data, ptr, prev) to use NonNull::from_ref(...) instead of unsafe pointer casts.

[graphite-app]

Merge activity

• Apr 9, 8:43 AM UTC: overlookmotel added this pull request to the Graphite merge queue.
• Apr 9, 9:10 AM UTC: Merged by the Graphite merge queue.