install: point at the failing part of an invalid mode

[sylvestre]

_{Stack created with GitHub Stacks CLI • Give Feedback 💬}

[codspeed-hq]

Merging this PR will degrade performance by 3.29%

❌ 2 regressed benchmarks
✅ 345 untouched benchmarks
⏩ 46 skipped benchmarks¹

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	Memory	factor_multiple_u64s[2]	58.6 KB	60.7 KB	-3.4%
❌	Memory	seq_custom_separator	63 KB	65 KB	-3.18%

Tip

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

---

_{Comparing mode-diag-5-install (fb5e04a) with mode-diag-4-mknod (6295e0c)}

Footnotes

1. 46 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. ↩

[github-actions]

GNU testsuite comparison:

Skipping an intermittent issue tests/date/date-locale-hour (passes in this run but fails in the 'main' branch)
Congrats! The gnu test tests/seq/seq-epipe is now passing!
Skip an intermittent issue tests/tail/tail-n0f (was skipped on 'main', now failing)

[github-actions]

Binary size comparison:

Individual binary size comparison VS main (threshold: >=5% AND >=4 KB).

Total size of compared binaries: 147.69 MB (+72 KB, +0.05%)

Significant per-binary changes:
  install     1.24 MB ->    1.31 MB  (+72 KB, +5.66%)