IOException on compilation (filename too long) when code is checkout into an encrypted directory

[giabao]

This error can be fixed by adding scala scalacOptions ++= Seq("-Xmax-classfile-name", "100")

Refs:

• IOException on compilation (filename too long). scala/pickling#10
• https://issues.scala-lang.org/browse/SI-8199

[jrudolph]

IIUC this feature doesn't work together with separate compilation. So, I don't think it is something we can fix. If you have other info, please reopen.

[giabao]

what is "separate compilation"?

I clone spray (branch release/1.3) into my home folder - which is encrypted (I use ubuntu 12.04) and can't compile it.
When I add the above scalac options then I can run sbt test, sbt publish-local without error.

[jrudolph]

The question is if you can still use it together with other software not built with the same flag.

[jrudolph]

Here's a branch that shows what can happen if you use the flag without using it in all projects:

https://github.com/jrudolph/spray/compare/w;max-classfile-name-breakage?expand=1

Run test:run in project spray-routing-tests.

[jrudolph]

Btw. it might be that adding the flag doesn't break something right now but that's just coincidental because the flag is more likely to apply to classes with long names which in many cases are anonymous, implementation-private classes that won't be referenced from third parties. However, as the example shows, it could happen to public identifiers as well which could lead to silent breakage.