FIR crashes on Bool type resolution

Hello A snippet below crashes when I try to instantiate a Counter module in my design. Bool type resolution being the victim. If I use a function to implement a counter in my design, all works seamlessly: System: Ubuntu 16.04.5, Scala version: 2.11.12, Chisel version: 3.1.0 Code

package  counter_pkg 
import    chisel3._
import    chisel3.util._

class Counter (max:UInt, ena:Bool ) extends Module {
  val width = max.getWidth
    val io = IO (new Bundle {
    val out  = Output(UInt(width.W))
  })
    val x = RegInit(0.asUInt(width.W))
  x := Mux(x === max, 0.U, Mux (ena, x + 1.U, x))
  io.out := x
}

class CounterWrap extends Module {
  val io = IO (new Bundle {
    val out  = Output (UInt(16.W))
    })
   
  val idle :: run :: Nil = Enum (2)
  val state = RegInit(idle)
    val ena  = RegInit (false.B)
  ena := state === run
  val cnt  = Module (new Counter(16.U, **ena.toBool**)) // This won't compile if I remove .toBool
   io.out := 0.U
}

Execution Result Log

[info] [0.003] Elaborating design...
[info] [0.237] Done elaborating.
Total FIRRTL Compile Time: 327.7 ms
Total FIRRTL Compile Time: 35.0 ms
End of dependency graph
Circuit state created
Exception during evaluation: mux(WRef(cnt._T_12,UIntType(IntWidth(6)),NodeKind,MALE)) must be (0|1).U<1> was 18.PU<6>  @[Counter.scala 16:32:@12.4]  @[Counter.scala 16:32:@12.4]
Expression Evaluation stack
   0 cnt.x:Reg -> mux(cnt.reset, UInt<5>("h0"), cnt._T_15)
   1 cnt._T_15:Node -> mux(cnt._T_9, UInt<1>("h0"), cnt._T_14)
   2 cnt._T_14:Node -> mux(cnt._T_12, cnt._T_13, cnt.x)
Error: InterpreterExecption(mux(WRef(cnt._T_12,UIntType(IntWidth(6)),NodeKind,MALE)) must be (0|1).U<1> was 18.PU<6>  @[Counter.scala 16:32:@12.4] during warmup evaluation
Exception during evaluation: mux(WRef(cnt._T_12,UIntType(IntWidth(6)),NodeKind,MALE)) must be (0|1).U<1> was 18.PU<6>  @[Counter.scala 16:32:@12.4]  @[Counter.scala 16:32:@12.4]
Expression Evaluation stack
   0 cnt.x:Reg -> mux(cnt.reset, UInt<5>("h0"), cnt._T_15)
   1 cnt._T_15:Node -> mux(cnt._T_9, UInt<1>("h0"), cnt._T_14)
   2 cnt._T_14:Node -> mux(cnt._T_12, cnt._T_13, cnt.x)
[error] (run-main-2) firrtl_interpreter.InterpreterException: mux(WRef(cnt._T_12,UIntType(IntWidth(6)),NodeKind,MALE)) must be (0|1).U<1> was 18.PU<6>  @[Counter.scala 16:32:@12.4]
[error] firrtl_interpreter.InterpreterException: mux(WRef(cnt._T_12,UIntType(IntWidth(6)),NodeKind,MALE)) must be (0|1).U<1> was 18.PU<6>  @[Counter.scala 16:32:@12.4]
[error] 	at firrtl_interpreter.InterpreterException$.apply(InterpreterException.scala:10)
[error] 	at firrtl_interpreter.LoFirrtlExpressionEvaluator.evaluate(LoFirrtlExpressionEvaluator.scala:302)
[error] 	at firrtl_interpreter.LoFirrtlExpressionEvaluator$$anonfun$5.apply(LoFirrtlExpressionEvaluator.scala:453)

[seldridge]

It helps when I compile it before posting. It should be io.en, not en. I corrected the example above and added a note that I edited it.

@edwardcwang beat me to the punch! GitHub flavored Markdown provides a lot of neat functionality. There’s a small guide here.

[edwardcwang]

Also try io.en instead of just en since en is a signal inside of io.