ClangdTests.exe/TUSchedulerTests.ManyUpdates flaky on windows

[nico]

Bugzilla Link	50773
Version	unspecified
OS	All
CC	@sam-mccall

Extended Description

https://lab.llvm.org/buildbot/#/builders/123/builds/4487/steps/12/logs/stdio :

Reusing preamble version 0 for version 5 of C:\clangd-test\foo2.cpp
Assertion failed: Requests.empty() && "No new normal tasks can be scheduled concurrently with " "blockUntilIdle(): ASTWorker isn't threadsafe", file C:\b\slave\clang-x64-windows-msvc\llvm-project\clang-tools-extra\clangd\TUScheduler.cpp, line 1390
********************
Testing:  0.. 10.. 20.. 30.. 40.. 50.. 60.. 70.. 80.. 90.. 
********************
Failed Tests (1):
  Clangd Unit Tests :: ./ClangdTests.exe/TUSchedulerTests.ManyUpdates

Same on https://lab.llvm.org/buildbot/#/builders/123/builds/4485/steps/12/logs/stdio

Same on https://lab.llvm.org/buildbot/#/builders/123/builds/4481/steps/12/logs/stdio

Same on https://lab.llvm.org/buildbot/#/builders/123/builds/4564/steps/12/logs/stdio

From a random sample, it looks like the majority of failures on https://lab.llvm.org/buildbot/#/builders/123 is due to this.

[nico]

(#48455 is about a hang in this test suite -- looks like this code has a concurrency bug somewhere)

[nico]

This is happening a lot right now:

http://45.33.8.238/win/80342/step_9.txt
http://45.33.8.238/win/80320/step_9.txt
http://45.33.8.238/win/80314/step_9.txt
http://45.33.8.238/win/80293/step_9.txt
http://45.33.8.238/win/80291/step_9.txt

5 failures in the last 1.5 days.

[nico]

@ilya-biryukov added this test over 5 years ago in https://reviews.llvm.org/D42174.

[HighCommander4]

See also clangd/clangd#1712

[kadircet]

Hi all, sorry for missing those.

Hi @nico, I was checking the failures in the past week, and they don't seem to be from clangd. Is this still relevant for the build bot you're running?

[kadircet]

closing as this doesn't seem to be showing up anymore on the relevant build bots at least, and despite the original bug being about a correctness issue, the recent failures are all timeouts.