uucore: build with --no-default-features

[xtqqczze]

Closes #15339.
Closes #15362.

cargo clippy -q -p uucore --all-targets --no-default-features

[codspeed]

Merging this PR will degrade performance by 3.86%

⚠️ 120 benchmarks spent significant time in system calls

System calls cannot be consistently instrumented, so they are not included in the measure, which understates the real cost. Please switch to the Walltime instrument to accurately measure system calls.

Measurement and system calls

• csplit_line_number
• cksum_default
• dd_copy_partial
• du_wide_tree[(5000, 500)]
• dd_copy_64k_blocks
• df_deep_directory
• cksum_sysv
• cksum_crc32b
• du_deep_tree[(100, 3)]
• cut_fields_newline_delim
• …and 110 more

ℹ️ 1 benchmark has no flame graph

The flamegraph could not be generated because too much time was spent in runtime internals, making the visualization not useful for performance analysis.

• sort_dictionary_order[500000]

⚡ 2 improved benchmarks
❌ 2 regressed benchmarks
✅ 397 untouched benchmarks
⏩ 70 skipped benchmarks¹

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌ ⚠️	Simulation	csplit_line_number	48 ms	56.3 ms	-14.82%
❌	Simulation	csplit_regex_pattern	66.3 ms	73.7 ms	-10.04%
⚡	Simulation	factor_three_39_bit_primes	598.6 ms	561.1 ms	+6.68%
⚡	Simulation	factor_five_38_bit_primes	1.9 s	1.8 s	+4.53%

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 xtqqczze:GH15339 (c545582) with main (175f6e1)²}

Footnotes

1. 70 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 (4945ecf) during the generation of this report, so 175f6e1 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩