False postive discarded non-Unit value ... Add : Unit to discard silently

[joan38]

Compiler version

3.3.5, 3.6.4, 3.7.0

Minimized code

import scribe.*
@main def run: Unit =
  Logger.root.withHandler(minimumLevel = Some(Level.Error)).replace(): Unit

https://scastie.scala-lang.org/a9rhjXNDS72Ve5vg8XOrrw

Output

discarded non-Unit value of type scribe.Logger. Add : Unit to discard silently.

Expectation

The : Unit should remove the warning

Workaround

val _ = Logger.root.withHandler(minimumLevel = Some(Level.Error)).replace()

Thanks

[som-snytt]

More minimized

class C(c: Int):
  def f(i: Int, j: Int = c) = i + j

def test2: Unit =
  C(27).f(i = 42): Unit

where the default arg becomes

    def test2: Unit =
      {
        {
          val $1$: C = new C(27)
          $1$.f(i = 42, $1$.f$default$2)
        }
        ()
      }:Unit

[joan38]

Amazing thanks guys!