Odd issue grouping

[michaelni]

Hi
It seems oss-fuzz is grouping many unrelated testcases in the same issues.
For example issue 20492
https://oss-fuzz.com/testcases?q=group%3A5741286006456320 had many linked to 20492
their similarity where maybe 1-3 lines of the stacktrace, but even from seperate fuzz targets

Another example is issue 20659 which still has unlrelated issues grouped together at the moment

The real problem is that these issues where not vissible from the notification mails so only when i looked at why the issues where still open after thinking that they had been fixed did i realize that there where multiple unrelated testcases hiding threre

[inferno-chromium]

This is probably because 2nd frame is too similar(something*decode_frame) and 3rd frame is same(decode_simple_internal).
decode_frame
decode_simple_internal

It is really hard problem to how to best group. If we dont group, we file duplicate bugs. In this case, once you fix a bug and its incorrect group variants are not fixed, we will file a new bug for them in a few days.

[michaelni]

Is it possible to make grouped issues more vissible in mail notices ?
Or is there something i can do to stay more aware of this when primarly using the mail notices?

[inferno-chromium]

This is hard from implementation perspective (since groups get generated over time as we see new testcase). But on any testcase report, e.g. https://oss-fuzz.com/testcase-detail/5639509530378240, you can always check if this is part of a group, e.g. "Related: Group XYZ". You can click that link to see grouped testcases.
Can this decode_simple_internal be marked as inline function, then it will vanish from crash signature ?

[michaelni]

Can this decode_simple_internal be marked as inline function, then it will vanish from crash signature ?

Thanks for the suggestion, i posted a patch doing that to ffmpeg-devel
https://patchwork.ffmpeg.org/project/ffmpeg/patch/20200511224635.19071-1-michael@niedermayer.cc/

[michaelni]

suggested change applied to FFmpeg