Deadlock when invoking hover/reference resolution in the Eclipse LWB

[Gohla]

Summary

A deadlock can occur sometimes when invoking hover/reference resolution in the Eclipse LWB.

What you did

Build a language and then invoke hover/reference resolution.

What you expected to happen

No deadlock to occur.

What actually happened

A deadlock occurs.

Context

• Spoofax version: 0.11.10
• Operating system & version: Any

Additional information

Thread dump: https://gist.github.com/Gohla/661524b25904b5010f3ddd98525a2057 The dump indicates that both the:

• Main thread (which is invoking hover) is waiting on a lock because it walks the project resources (due to executing the Sdf3GetSourceFiles task), and this lock is probably locked because the Spoofax LWB builder thread holds a lock on the entire project.
• Spoofax LWB builder thread probably locks the entire project, but is stuck waiting on a lock for writing to the console.

It is unclear to me why the builder thread is stuck waiting on the console.

[Gohla]

Fixed by https://github.com/metaborg/spoofax-pie/commit/04b6515dacdf0fcb6ae90780f4ce1e7e31fa9af1, to be released in 0.11.12.