Decompilers comparison: how independent are the code bases and dependencies - could similarities be due to common dependencies on lower level resources?

Decompilers comparison: Can you speculate as to the impact for later version of Java (9/10) with more complex features?

I recently heard a talk from Google that they reverse all novel language features to JDK 7? Would such a tool help decompilers?

For decompilation: have you noticed specific features (e.g., inner classes, lambdas) that lead to recompilation problems?

Decompilers comparison: Could you briefly explain the result of other equivalence (syntactic equivalence and readability)?

Recall without precision is easy. Precision without recall is easy. So why create corpi to evaluate one without the other?