aux-bin: Avoid old .so files from old tests; clean auxiliary dir root

[Enselic]

Also fix the typo pointed out here.

Closes #124465

[rustbot]

r? @davidtwco

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[rustbot]

Some changes occurred in src/tools/compiletest

cc @jieyouxu

[jieyouxu]

Thanks!

@bors r+ rollup

[bors]

📌 Commit de3eff7 has been approved by jieyouxu

It is now in the queue for this repository.

[bors]

⌛ Testing commit de3eff7 with merge 9084601...

[bors]

☀️ Test successful - checks-actions
Approved by: jieyouxu
Pushing 9084601 to master...

[rust-timer]

Finished benchmarking commit (9084601): comparison URL.

Overall result: no relevant changes - no action needed

@rustbot label: -perf-regression

Instruction count

This benchmark run did not return any relevant results for this metric.

Max RSS (memory usage)

Results

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-3.6%	[-3.6%, -3.6%]	1
All ❌✅ (primary)	-	-	0

Cycles

This benchmark run did not return any relevant results for this metric.

Binary size

This benchmark run did not return any relevant results for this metric.

Bootstrap: 671.911s -> 672.94s (0.15%)
Artifact size: 315.98 MiB -> 315.94 MiB (-0.01%)