Meta tracking issue for spurious CI failures

[jieyouxu]

This is a (meta) tracking issue intended to make it easier to find the specific spurious CI failure issues.

Platform-specific

• Tracking Issue for high failure rates on Windows MSVC CI with filesystem errors #127883; CI-spurious-fail-msvc CI spurious failure: target env msvc
• ci: spurious failure tests\mir-opt\strip_debuginfo.rs Cannot create a file when that file already exists.` #134351; CI-spurious-fail-msvc CI spurious failure: target env msvc
• Tracking Issue for spurious mingw CI failures #133958; CI-spurious-fail-mingw CI spurious failure: target env mingw
• SIGSEGV/SIGILL while building rustc itself in x86_64 apple CI jobs #134220; CI-spurious-x86_64-apple-SIGSEGV-SIGILL CI spurious failure: SIGSEGV/SIGILL while building rustc itself on x86_64-apple

Runner-specific

• Sporadic errors with armhf-gnu CI remote test runs #97669
• (Unclear, under investigation) new arm64 runners behave strangely Compiler crashes/ICEs on new aarch64 GHA runners/Azure Cobalt 100 (Neoverse N2) CPUs #135867

Known problems

LLVM

• llvm-tblgen Segmentation fault in CI on dist-aarch64-apple #109624
• random Empty/Tombstone LLVM assertion error on i686-msvc CI #110290

Pointer provenance ABA lockless queue test failures

• ABA pointer provenance lockless queue test failures due to ABA-problem with pointer provenance in lockless queues #121950 in the miri test suite, CI-ABA-ptr-provenance-lockless-queue-fail CI spurious failure: related to #121950

Linkers

rust-lld can sometimes crash quite often

• Linking with rust-lld causes SIGSEGV in FFI code #128286

Networking failures

• Tracking issue for spurious network failures on bots #40474

Bot troubles

• Bors: 422 Update is not a fast forward #43535

Possible mitigation approaches

• bootstrap: retry cargo invocations if stderr contains a known pattern #134472

Others

• Suspected cosmic bitflips or faulty memory cell: Rollup of 8 pull requests #136084 (comment)
• Upload metrics to datadog npm ci segfault: Rollup of 12 pull requests #136572 (comment), rustdoc: run css and html minifier at build instead of runtime #136253 (comment)

[matthiaskrgr]

https://github.com/rust-lang/rust/issues?q=is%3Aissue%20state%3Aopen%20label%3AA-spurious