Deleting files under directory watching on Windows can cause VM crash

[aam]

From flutter/flutter#46616 several races were fixed and flutter concerns seem to be addressed, but repro that @DanTup referenced there sill causes crashes in Danny's set up.

Crashdump is available here https://drive.google.com/a/google.com/file/d/186LwO1g9p-eCW9jFmX7sqfhPSmM1hUlI/view?usp=sharing

[DanTup]

Although my repro was quite contrived, I think Dart-Code/Dart-Code#2287 (comment) may be a user still hitting this when working on Flutter (using the master branch it's happening less, but still happening).

[sortie]

@zichangg Have you tried if this crash can be reproduced?

[DanTup]

This has come up a few times again in Dart-Code/Dart-Code#2704 where running a Flutter app crashes the analysis server. Although I can't reproduce it when running the Flutter app, I have reproduced it a few times running flutter clean.

• (On Windows)
• Run the flutter_gallery app on Android emulator
• Run flutter clean
• Try to hover over anything in editor - pops up Dart Analyzer has terminated

If it doesn't repro, I just re-run the app, stop it, then clean.

Here is a crash dump:

https://drive.google.com/file/d/119wljBikMtmlE2iQsEKaMUEa9NtMQL7x/view?usp=sharing

The version of Flutter I used was

Flutter 1.21.0-8.0.pre.140 • channel master • https://github.com/DanTup/flutter.git
Framework • revision c8d051295a (7 hours ago) • 2020-08-11 00:26:02 -0400
Engine • revision a62703778b
Tools • Dart 2.10.0 (build 2.10.0-5.0.dev e2a67723ca)

Last things in the analyzer instrumentation log are:

1597143277987:Req:{"id"::"68","method"::"edit.getAssists","params"::{"file"::"M::\\Dev\\Google\\flutter_gallery\\lib\\main.dart","length"::0,"offset"::1041},"clientRequestTime"::1597143277987}
1597143277987:Req:{"id"::"69","method"::"edit.getAvailableRefactorings","params"::{"file"::"M::\\Dev\\Google\\flutter_gallery\\lib\\main.dart","length"::0,"offset"::1041},"clientRequestTime"::1597143277987}
1597143277988:Res:{"id"::"69","result"::{"kinds"::[]}}
1597143277992:Res:{"id"::"68","result"::{"assists"::[]}}
1597143280839:Watch:M::\Dev\Google\flutter_gallery:M::\Dev\Google\flutter_gallery\build\71910eb539bb7711546ff654f08685af\gen_localizations.stamp:remove
1597143280840:Watch:M::\Dev\Google\flutter_gallery:M::\Dev\Google\flutter_gallery\build\app\generated\not_namespaced_r_class_sources\debug\processDebugResources\r\androidx\activity\R.java:remove
1597143280841:Watch:M::\Dev\Google\flutter_gallery:M::\Dev\Google\flutter_gallery\build\app\generated\not_namespaced_r_class_sources\debug\processDebugResources\r\androidx\arch\core\R.java:remove
1597143280841:Watch:M::\Dev\Google\flutter_gallery:M::\Dev\Google\flutter_gallery\build\app\generated\not_namespaced_r_class_sources\debug\processDebugResources\r\androidx\core\R.java:remove
1597143280843:Watch:M::\Dev\Google\flutter_gallery:M::\Dev\Google\flutter_gallery\build\app\generated\not_namespaced_r_class_sources\debug\processDebugResources\r\androidx\customview\R.java:remove
1597143280844:Watch:M::\Dev\Google\flutter_gallery:M::\Dev\Google\flutter_gallery\build\app\generated\not_namespaced_r_class_sources\debug\processDebugResources\r\androidx\fragment\R.java:remove
1597143280844:Watch:M::\Dev\Google\flutter_gallery:M::\Dev\Google\flutter_gallery\build\app\generated\not_namespaced_r_class_sources\debug\processDebugResources\r\androidx\lifecycle\livedata\core\R.java:remove
1597143280844:Watch:M::\Dev\Google\flutter_gallery:M::\Dev\Google\flutter_gallery\build\app\generated\not_namespaced_r_class_sources\debug\processDebugResources\r\androidx\lifecycle\livedata\R.java:remove
1597143280844:Watch:M::\Dev\Google\flutter_gallery:M::\Dev\Google\flutter_gallery\build\app\generated\not_namespaced_r_class_sources\debug\processDebugResources\r\androidx\lifecycle\R.java:remove
1597143280845:Watch:M::\Dev\Google\flutter_gallery:M::\Dev\Google\flutter_gallery\build\app\generated\not_namespaced_r_class_sources\debug\processDebugResources\r\androidx\lifecycle\viewmodel\R.java:remove
1597143280845:Watch:M::\Dev\Google\flutter_gallery:M::\Dev\Google\flutter_gallery\build\app\generated\not_namespaced_r_class_sources\debug\processDebugResources\r\androidx\loader\R.java:remove
1597143280845:Watch:M::\Dev\Google\flutter_gallery:M::\Dev\Google\flutter_gallery\build\app\generated\not_namespaced_r_class_sources\debug\processDebugResources\r\androidx\savedstate\R.java:remove
1597143280845:Watch:M::\Dev\Google\flutter_gallery:M::\Dev\Google\flutter_gallery\build\app\generated\not_namespaced_r_class_sources\debug\processDebugResources\r\androidx\versionedparcelable\R.java:remove
1597143280845:Watch:M::\Dev\Google\flutter_gallery:M::\Dev\Google\flutter_gallery\build\app\generated\not_namespaced_r_class_sources\debug\processDebugResources\r\androidx\viewpager\R.java:remove

Full analyzer instrumentation log: analyzer.instrum.txt

[devoncarew]

@zichangg @a-siva - Danny's been seeing user reports of this more often. It may or may not be the same as the issue reported in January. Danny does have a consistent repro for this (as well as a crash dump), and is happy to test out possible fixes.

[a-siva]

@DanTup if you have consistent repro instructions could you post them here.

[DanTup]

@a-siva I posted some notes above with a crash dump: #40348 (comment)

It doesn't repro 100% of the time, but if I build/clean a few times, it happens maybe 1-2 times in 5 on my PC.