Tidy up dump-ice-to-disk and make assertion failures dump ICE messages

[jieyouxu]

For the future traveler: if you did a git blame and found this PR that last modified dump-ice-to-disk because the test failed in a completely unrelated PR, then I'm afraid our ICE dump may have regressed or somehow behaves differently on i686-mingw.

A bit of clean up to the dump-ice-to-disk test.

• Fixes/updates the top-level comment.
• Add a FIXME pointing to tests/run-make/dump-ice-to-disk is flakey on i686-mingw #128911 for flakiness.
• Instead of trying to manually cleanup rustc-ice*.txt dumps, run each test instance in a separate temp directory.
• Explicitly make RUSTC_ICE unavailable in one of the -Zmetrics-dir test case to not have interference from environment.
• Make assertion failures (on ICE dump line count mismatch) extremely verbose to help debug why this test is flakey in CI (tests/run-make/dump-ice-to-disk is flakey on i686-mingw #128911).

Contains a fix by @saethlin in #128909, should wait until that is merged then rebase on top.

try-job: aarch64-gnu
try-job: aarch64-apple
try-job: x86_64-msvc
try-job: i686-mingw
try-job: test-various

[rustbot]

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[jieyouxu]

Running a couple of try jobs for sanity check.

@bors try

[jieyouxu]

In the meantime, @rustbot author

[bors]

⌛ Trying commit 30b7e0b with merge ded2b46...

[bors]

☀️ Try build successful - checks-actions
Build commit: ded2b46 (ded2b46501204598d0759fbd5e38516f4331e4c6)

[jieyouxu]

@rustbot ready

[compiler-errors]

r=me when that dependency lands

[compiler-errors]

Needs rebase then r=me

@rustbot author

[jieyouxu]

Based on https://rust-lang.zulipchat.com/#narrow/stream/182449-t-compiler.2Fhelp/topic/getting.20.60Box.3Cdyn.20Any.3E.60.20as.20ICE.20message I am suspecting that this test is in fact not flakey and is correctly doing its job, and that our ICE dumps actually regressed. We'll see if the verbose dumps reveal anything in completely unrelated PRs again.

[jieyouxu]

In any case, we can merge the verbose dumping first to see if it fails somewhere else completely unrelated and how it failed.

[jieyouxu]

... I feel like PR CI is doing something weird here, it's been 2 hours and usually PR CI doesn't take that long. In any case, we'll see this in full CI if this fails.

@bors r=@compiler-errors rollup=iffy (this test is known to be flakey on i686-mingw)

[jieyouxu]

Oh wait can't do that, or else bors might send this straight to master without any testing.
@bors r- retry

[jieyouxu]

Please don't be waiting on bors! @bors r-

[jieyouxu]

bors please wait! @bors r-

[jieyouxu]

Re-opening since the try job on the draft PR #128958 is done. Maybe it won't be so cursed this time.

[jieyouxu]

@bors r=@compiler-errors rollup=iffy (this test is known to be flakey on i686-mingw)

[bors]

📌 Commit 960e7b5 has been approved by compiler-errors

It is now in the queue for this repository.

[jieyouxu]

I'm actually going to bump this higher because #122362 failed on dump-ice-to-disk again on i686-mingw.

@bors p=1 (other full CI is failing on this test, and this PR tries to make the failure cause more obvious)

[jieyouxu]

Going to ignore this test on windows so I can investigate on the side and not block full CI.

[jieyouxu]

@bors r=@compiler-errors

[bors]

📌 Commit 6dc300b has been approved by compiler-errors

It is now in the queue for this repository.

[bors]

⌛ Testing commit 6dc300b with merge 5e5ec8a...

[bors]

☀️ Test successful - checks-actions
Approved by: compiler-errors
Pushing 5e5ec8a to master...

[rust-timer]

Finished benchmarking commit (5e5ec8a): 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 2.3%, secondary -4.9%)

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)	2.3%	[2.3%, 2.3%]	1
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-4.9%	[-4.9%, -4.9%]	1
All ❌✅ (primary)	2.3%	[2.3%, 2.3%]	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: 757.742s -> 758.668s (0.12%)
Artifact size: 339.25 MiB -> 339.27 MiB (0.01%)