In JDK-8150009 we are trying to define how and where debuginfo should be available during our build life cycle. The full solution is also depending on JDK-8136777 which will take more time to get done. One thing is pretty clear and that is that jmod files cannot contain debuginfo. It's quite urgent to fix that particular problem since it is currently eating a lot of space by being duplicated in the jdk image.

I already have a patch prepared for solving this particular issue and it shouldn't conflict much with other work in this area so I would like to push that separately first.