Rudder

In Cfclerk, we are seing stack overflow errors like:

[ERROR] error: java.lang.StackOverflowError
[INFO]     at scala.tools.nsc.typechecker.Typers$Typer.scala$tools$nsc$typechecker$Typers$Typer$$typedInternal(Typers.scala:5379)
[INFO]     at scala.tools.nsc.typechecker.Typers$Typer.body$2(Typers.scala:5370)
[INFO]     at scala.tools.nsc.typechecker.Typers$Typer.typed(Typers.scala:5374)
[INFO]     at scala.tools.nsc.typechecker.Typers$Typer.typed(Typers.scala:5463)
[INFO]     at scala.tools.nsc.typechecker.Typers$Typer.computeType(Typers.scala:5554)
[INFO]     at scala.tools.nsc.typechecker.Namers$Namer.assignTypeToTree(Namers.scala:880)
[INFO]     at scala.tools.nsc.typechecker.Namers$Namer.valDefSig(Namers.scala:1382)
[INFO]     at scala.tools.nsc.typechecker.Namers$Namer.getSig$1(Namers.scala:1533)
[INFO]     at scala.tools.nsc.typechecker.Namers$Namer.typeSig(Namers.scala:1542)
[INFO]     at scala.tools.nsc.typechecker.Namers$Namer$$anonfun$monoTypeCompleter$1$$anonfun$apply$1.apply$mcV$sp(Namers.scala:782)
[INFO]     at scala.tools.nsc.typechecker.Namers$Namer$$anonfun$monoTypeCompleter$1$$anonfun$apply$1.apply(Namers.scala:781)
[INFO]     at scala.tools.nsc.typechecker.Namers$Namer$$anonfun$monoTypeCompleter$1$$anonfun$apply$1.apply(Namers.scala:781)
[INFO]     at scala.tools.nsc.typechecker.Namers$Namer.scala$tools$nsc$typechecker$Namers$Namer$$logAndValidate(Namers.scala:1569)
[INFO]     at scala.tools.nsc.typechecker.Namers$Namer$$anonfun$monoTypeCompleter$1.apply(Namers.scala:781)
[INFO]     at scala.tools.nsc.typechecker.Namers$Namer$$anonfun$monoTypeCompleter$1.apply(Namers.scala:773)
[INFO]     at scala.tools.nsc.typechecker.Namers$$anon$1.completeImpl(Namers.scala:1685)
[INFO]     at scala.tools.nsc.typechecker.Namers$LockingTypeCompleter$class.complete(Namers.scala:1693)
[INFO]     at scala.tools.nsc.typechecker.Namers$$anon$1.complete(Namers.scala:1683)
[INFO]     at scala.reflect.internal.Symbols$Symbol.info(Symbols.scala:1514)
[INFO]     at scala.reflect.internal.Symbols$Symbol.initialize(Symbols.scala:1659)
[INFO]     at scala.tools.nsc.typechecker.Typers$Typer.typed1(Typers.scala:5008)
[INFO]     at scala.tools.nsc.typechecker.Typers$Typer.runTyper$1(Typers.scala:5396)

Moreover, we don't set the required Xmx, which may be why builds are sooooo slow.