Fix duplicate labels emitted in render_multispan_macro_backtrace()

[gurry]

This PR replaces the Vec used to store labels with an FxIndexSet in order to eliminate duplicates

Fixes #116836

[rustbot]

r? @petrochenkov

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[petrochenkov]

@bors r+ rollup

[bors]

📌 Commit 88c8714 has been approved by petrochenkov

It is now in the queue for this repository.

[matthiaskrgr]

@bors r- #116848 (comment)

[gurry]

@matthiaskrgr I've fixed the failing test

@rustbot label -S-waiting-on-author +S-waiting-on-review

[petrochenkov]

@bors r+

[bors]

📌 Commit 0091166 has been approved by petrochenkov

It is now in the queue for this repository.

[bors]

⌛ Testing commit 0091166 with merge ae466d2...

[bors]

☀️ Test successful - checks-actions
Approved by: petrochenkov
Pushing ae466d2 to master...

[rust-timer]

Finished benchmarking commit (ae466d2): 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)	-3.4%	[-3.4%, -3.4%]	1
All ❌✅ (primary)	-	-	0

Cycles

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)	4.1%	[1.7%, 10.7%]	6
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

Binary size

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

Bootstrap: 630.247s -> 630.044s (-0.03%)
Artifact size: 304.06 MiB -> 304.02 MiB (-0.01%)