perf: removed unnecessary let for return only in layout.rs

[Azzybana]

perf: removed unnecessary let for return only

[rustbot]

r? @scottmcm

rustbot has assigned @scottmcm.
They will have a look at your PR within the next two weeks and either review your PR or reassign to another reviewer.

Use r? to explicitly pick a reviewer

[bjorn3]

This won't have any performance impact. At best it could make the code nicer to look at.

[hkBst]

The commentary above already contains the same information as the let-for-comment-binding, so I suppose getting rid of it is fine.

[nnethercote]

@bors r+ rollup

[bors]

📌 Commit 79c0897 has been approved by nnethercote

It is now in the queue for this repository.

[mati865]

How about rewording the title and description?
Using perf here is misleading since this has absolutely zero effect on the performance.

[bors]

⌛ Testing commit 79c0897 with merge 292be5c...

[bors]

☀️ Test successful - checks-actions
Approved by: nnethercote
Pushing 292be5c to master...

[github-actions]

What is this?

This is an experimental post-merge analysis report that shows differences in test outcomes between the merged PR and its parent PR.

Comparing 292db4a (parent) -> 292be5c (this PR)

Test differences

Show 11 test diffs

11 doctest diffs were found. These are ignored, as they are noisy.

Test dashboard

Run

cargo run --manifest-path src/ci/citool/Cargo.toml -- \
    test-dashboard 292be5c7c05138d753bbd4b30db7a3f1a5c914f7 --output-dir test-dashboard

And then open test-dashboard/index.html in your browser to see an overview of all executed tests.

Job duration changes

1. dist-s390x-linux: 5041.2s -> 5695.5s (+13.0%)
2. dist-riscv64-linux: 4824.7s -> 5412.4s (+12.2%)
3. i686-msvc-2: 8051.2s -> 7274.1s (-9.7%)
4. x86_64-msvc-2: 6438.9s -> 7047.0s (+9.4%)
5. dist-ohos-x86_64: 4397.6s -> 4784.2s (+8.8%)
6. dist-apple-various: 3962.7s -> 4307.4s (+8.7%)
7. dist-ohos-aarch64: 4283.0s -> 4652.9s (+8.6%)
8. x86_64-msvc-ext2: 6121.1s -> 5598.1s (-8.5%)
9. dist-loongarch64-linux: 5292.4s -> 5719.4s (+8.1%)
10. dist-aarch64-apple: 8310.2s -> 7640.5s (-8.1%)

How to interpret the job duration changes?

Job durations can vary a lot, based on the actual runner instance
that executed the job, system noise, invalidated caches, etc. The table above is provided
mostly for t-infra members, for simpler debugging of potential CI slow-downs.

[rust-timer]

Finished benchmarking commit (292be5c): 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 (primary 3.1%, secondary -0.2%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	3.1%	[3.1%, 3.1%]	1
Regressions ❌ (secondary)	1.8%	[1.8%, 1.8%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-2.2%	[-2.2%, -2.2%]	1
All ❌✅ (primary)	3.1%	[3.1%, 3.1%]	1

Cycles

Results (secondary -0.6%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	2.1%	[2.1%, 2.1%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-3.2%	[-3.2%, -3.2%]	1
All ❌✅ (primary)	-	-	0

Binary size

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

Bootstrap: 476.353s -> 475.908s (-0.09%)
Artifact size: 390.24 MiB -> 390.25 MiB (0.00%)