fix(printf): do not panic when field width exceeds u16::MAX

[VedantMadane]

Summary

fix(printf): do not panic when field width exceeds u16::MAX

Changes

• num_format.rs: manual padding path when width > u16::MAX
• test_printf.rs: regression for %65536d

Fixes #13850

[github-actions]

GNU testsuite comparison:

Skip an intermittent issue tests/cut/bounded-memory (fails in this run but passes in the 'main' branch)
Skip an intermittent issue tests/tail/symlink (fails in this run but passes in the 'main' branch)
Note: The gnu test tests/cut/cut-huge-range is now being skipped but was previously passing.
Congrats! The gnu test tests/dd/no-allocate is now passing!
Congrats! The gnu test tests/tail/tail-n0f is now passing!

[codspeed-hq]

Merging this PR will regress 1 benchmark

⚠️ Different runtime environments detected

Some benchmarks with significant performance changes were compared across different runtime environments,
which may affect the accuracy of the results.

Open the report in CodSpeed to investigate

⚡ 1 improved benchmark
❌ 1 regressed benchmark
✅ 131 untouched benchmarks
⏩ 274 skipped benchmarks¹

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	Simulation	du_summarize_balanced_tree[(5, 4, 10)]	16.1 ms	16.8 ms	-3.86%
⚡	Simulation	seq_formatted	175.6 ms	160.1 ms	+9.65%

Tip

Investigate this regression by commenting @codspeedbot fix this regression on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing VedantMadane:fix/issue-13850 (50a5154) with main (a9b64fc)²}

Footnotes

1. 274 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 (71ebb92) during the generation of this report, so a9b64fc was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

[codspeed-hq]

Unable to generate the performance report

There was an internal error while processing the run's data. We're working on fixing the issue. Feel free to contact us on Discord or at support@codspeed.io if the issue persists.

[sylvestre]

some jobs are failing, could you please have a look? thanks