fix: address redox build issues

[xtqqczze]

These changes are intended to help restore successful builds on Redox.

RUSTC_BOOTSTRAP=1 cargo clippy -q -Zbuild-std --all-targets --features feat_os_unix_redox --target i586-unknown-redox --target x86_64-unknown-redox

[github-actions]

GNU testsuite comparison:

Skip an intermittent issue tests/date/date-locale-hour (fails in this run but passes in the 'main' branch)

[sylvestre]

still draft?

[xtqqczze]

@sylvestre Would you be happy to merge this as-is, or do need CI in place first?

[sylvestre]

happy to merge it if the CI is green

[codspeed]

Merging this PR will improve performance by 3.04%

⚡ 1 improved benchmark
✅ 376 untouched benchmarks
⏩ 54 skipped benchmarks¹

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
⚡	Simulation	du_all_wide_tree[(5000, 500)]	38.8 ms	37.6 ms	+3.04%

Tip

Curious why performance improved? Comment @codspeedbot explain why performance improved on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing xtqqczze:redox-cast (41abf5a) with main (ea21b10)²}

Footnotes

1. 54 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. ↩

2. No successful run was found on main (47df573) during the generation of this report, so ea21b10 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩