catch_panic: warn about panicking payload drop

[RalfJung]

Warns about the footgun in #86027.

Will be unnecessary if panics escaping from drop leads to abort (rust-lang/rfcs#3288). But until that is enforced everywhere, let's warn users about this.

[rustbot]

r? @workingjubilee

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[workingjubilee]

lmao I keep forgetting about that.

@bors r+ rollup

[bors]

📌 Commit 42972f5 has been approved by workingjubilee

It is now in the queue for this repository.

[bors]

⌛ Testing commit 42972f5 with merge 204805a...

[bors]

☀️ Test successful - checks-actions
Approved by: workingjubilee
Pushing 204805a to master...

[rust-timer]

Finished benchmarking commit (204805a): 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)	3.8%	[3.8%, 3.8%]	1
Improvements ✅ (primary)	-1.4%	[-1.4%, -1.4%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-1.4%	[-1.4%, -1.4%]	1

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: 666.819s -> 669.024s (0.33%)
Artifact size: 315.68 MiB -> 315.68 MiB (0.00%)