We are seeing this problem quite often now
https://youtrack.jetbrains.com/issue/KT-48779#focus=Comments-27-5206280.0-0
This is a comment with more info and repository where it's reproducible (but kinda hard, it's not 100%, we're still investigating causes)
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What i'am thinking of is a flag that would crash build process instead of using fallback
It's important, because silent fallbacks degrade CI performance very badly, and is hard to look for: there is no API to get callbacks and add some alerting on it, so one should monitor build output for specific strings which is kinda meh..
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Flag is just a flextape, what is really needed is meaningful and actionable information of why daemon can't compile; which is not always accessible, even /tmp/kotlin-daemon*.log can contain no valuable info at all
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p.s. I'm ready to contribute such a flag if it will be considered good idea