std::alloc: use posix_memalign instead of memalign on solarish

[devnexen]

memalign on Solarish requires the alignment to be at least the size of a pointer, which we did not honor. posix_memalign also requires that, but that code path already takes care of this requirement.

close GH-124787

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[rustbot]

Some changes occurred in src/tools/cargo

cc @ehuss

[RalfJung]

Can't we just use posix_memalign? Solaris and Illumos seem to both have that. Then the diff would be just two lines, as we're already using posix_memalign by default when we don't have some other special case.

[devnexen]

If we do not care of solaris < 10 then it s possible indeed.

[RalfJung]

https://doc.rust-lang.org/rustc/platform-support.html explicitly says "Solaris 11" so I think indeed we do not care about Solaris 10 or older.

[RalfJung]

LGTM, thanks!
@bors r+

[bors]

📌 Commit 1e232fe has been approved by RalfJung

It is now in the queue for this repository.

[bors]

⌛ Testing commit 1e232fe with merge b71fa82...

[bors]

☀️ Test successful - checks-actions
Approved by: RalfJung
Pushing b71fa82 to master...

[rust-timer]

Finished benchmarking commit (b71fa82): comparison URL.

Overall result: ✅ improvements - no action needed

@rustbot label: -perf-regression

Instruction count

This is a highly reliable metric that was 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)	-0.1%	[-0.1%, -0.1%]	1
All ❌✅ (primary)	-	-	0

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)	-2.1%	[-2.4%, -1.8%]	4
Improvements ✅ (secondary)	-3.6%	[-4.2%, -2.9%]	2
All ❌✅ (primary)	-2.1%	[-2.4%, -1.8%]	4

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: 677.159s -> 675.425s (-0.26%)
Artifact size: 315.94 MiB -> 315.92 MiB (-0.01%)