100 implicits eat heap and slow down error reporting

<details><summary>Self-contained example</summary>

```scala
package foo

object Test {
  type F[T]
  val F: F[Int] = ???

  def f[T](t: T)(
    e1: F[T], e2: F[T], e3: F[T],
    e4: F[T], e5: F[T], e6: F[T],
    e7: F[T], e8: F[T], e9: F[T],
    e10: F[T], e11: F[T], e12: F[T],
  ) = ???
  f("foo")(
    F, F, F,
    F, F, F,
    F, F, F,
    F, F, F,
  )
}


object x extends X1 with X2

trait X1 extends Implicits
trait X2 extends Implicits

trait Implicits {
  type F[T]
  type G[T]

  given g1 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g2 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g3 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g4 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g5 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g6 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g7 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g8 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g9 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g10 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g11 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g12 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g13 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g14 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g15 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g16 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g17 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g18 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g19 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g20 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g21 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g22 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g23 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g24 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g25 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g26 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g27 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g28 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g29 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g30 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g31 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g32 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g33 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g34 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g35 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g36 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g37 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g38 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g39 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g40 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g41 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g42 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g43 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g44 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g45 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g46 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g47 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g48 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g49 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g50 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g51 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g52 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g53 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g54 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g55 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g56 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g57 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g58 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g59 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g60 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g61 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g62 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g63 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g64 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g65 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g66 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g67 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g68 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g69 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g70 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g71 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g72 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g73 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g74 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g75 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g76 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g77 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g78 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g79 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g80 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g81 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g82 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g83 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g84 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g85 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g86 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g87 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g88 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g89 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g90 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g91 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g92 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g93 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g94 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g95 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g96 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g97 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g98 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g99 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
  given g100 [T1: F, T2: F, T3: F, T4: F, T5: F, T6: F, T7: F, T8: F, T9: F, T10: F, T11: F, T12: F, T13: F, T14: F, T15: F, T16: F, T17: F, T18: F, T19: F, T20: F, T21: F, T22: F] as G[Int] = ???
}
```
</details>

Output (12 times):

```scala
-- [E007] Type Mismatch Error: /Users/kmetiuk/Projects/scala3/playground/upickle-oome/src/Test.scala:14:4
14 |    F, F, F,
   |    ^
   |    Found:    (foo.Test.F : foo.Test.F[Int])
   |    Required: foo.Test.F[T]
   |
   |    where:    T is a type variable with constraint >: ("foo" : String)
```

The error is correct, the time and space that the compilation takes up are inadequate:

<img width="1365" alt="Screenshot 2020-06-11 at 12 33 51" src="https://user-images.githubusercontent.com/2614813/84375421-d2bed580-abdf-11ea-9aca-cedde757a184.png">

The culprit seems to be `dotty.tools.dotc.core.Types$CachedAppliedType`:

<img width="1365" alt="Screenshot 2020-06-11 at 12 34 54" src="https://user-images.githubusercontent.com/2614813/84375528-fbdf6600-abdf-11ea-8f70-9a2bab0dcc9d.png">

I discovered it originally in upickle where I was getting an OOME from it:

```scala
java.lang.OutOfMemoryError: Java heap space: Java heap space
    HashSet.allocate compiler/src/dotty/tools/dotc/util/HashSet.scala:23
    HashSet.growTable compiler/src/dotty/tools/dotc/util/HashSet.scala:152
    HashSet.addEntryAt compiler/src/dotty/tools/dotc/util/HashSet.scala:61
    HashSet.addEntryAfterScan compiler/src/dotty/tools/dotc/util/HashSet.scala:138
    Uniques$AppliedUniques.enterIfNew compiler/src/dotty/tools/dotc/core/Uniques.scala:92
    Types$AppliedType$.apply compiler/src/dotty/tools/dotc/core/Types.scala:3965
    TypeApplications$.appliedTo$extension compiler/src/dotty/tools/dotc/core/TypeApplications.scala:346
    Types$AppliedType.derivedAppliedType compiler/src/dotty/tools/dotc/core/Types.scala:3939
    Types$TypeMap.derivedAppliedType compiler/src/dotty/tools/dotc/core/Types.scala:4885
    Types$TypeMap.mapOver compiler/src/dotty/tools/dotc/core/Types.scala:4943
    Substituters.substParams compiler/src/dotty/tools/dotc/core/Substituters.scala:157
    Contexts$Context.substParams compiler/src/dotty/tools/dotc/core/Contexts.scala:78
    Substituters$SubstParamsMap.apply compiler/src/dotty/tools/dotc/core/Substituters.scala:193
    Substituters$SubstParamsMap.apply compiler/src/dotty/tools/dotc/core/Substituters.scala:193
    List.mapConserve scala-library-2.13.2.jar/scala/collection/immutable/List.scala:472
    Types$TypeMap.mapOverLambda$1 compiler/src/dotty/tools/dotc/core/Types.scala:4972
    Types$TypeMap.mapOver compiler/src/dotty/tools/dotc/core/Types.scala:4976
    Substituters.substParams compiler/src/dotty/tools/dotc/core/Substituters.scala:157
    Contexts$Context.substParams compiler/src/dotty/tools/dotc/core/Contexts.scala:78
    Substituters$SubstParamsMap.apply compiler/src/dotty/tools/dotc/core/Substituters.scala:193
    Types$TypeMap.mapOverLambda$1 compiler/src/dotty/tools/dotc/core/Types.scala:4974
    Types$TypeMap.mapOver compiler/src/dotty/tools/dotc/core/Types.scala:4976
    Substituters.substParams compiler/src/dotty/tools/dotc/core/Substituters.scala:157
    Contexts$Context.substParams compiler/src/dotty/tools/dotc/core/Contexts.scala:78
    Types$Type.substParams compiler/src/dotty/tools/dotc/core/Types.scala:1579
    Types$LambdaType.instantiate compiler/src/dotty/tools/dotc/core/Types.scala:3169
    Types$MethodOrPoly.instantiate compiler/src/dotty/tools/dotc/core/Types.scala:3204
    TypeAssigner.assignType compiler/src/dotty/tools/dotc/typer/TypeAssigner.scala:367
    Typer.assignType compiler/src/dotty/tools/dotc/typer/Typer.scala:84
    tpd$.TypeApply compiler/src/dotty/tools/dotc/ast/tpd.scala:51
    tpd$TreeOps$.appliedToTypeTrees$extension compiler/src/dotty/tools/dotc/ast/tpd.scala:932
    Typer.adapt1 compiler/src/dotty/tools/dotc/typer/Typer.scala:3481
```

It seems something to do with applied types being generated in excessive quantities. In this self-contained example, I was not able to get an OOME but I was able to grow the heap to the maximal size. Probably doesn't take much to tip the compiler to OOME beyond that.

What I discovered influences `dotty.tools.dotc.core.Types$CachedAppliedType` count and compilation times:

1. Number of `F[T]` parameters to the `f` function – linear growth of object count
2. Number of implicits in `Implicits`: increase from 30 to 60 gave 4 times more objects
3. Number of traits `x` inherits from: with 1 or less `X*` trait, the slowdown disappears completely. 2 is the minimal number to reproduce the slowdown. Increasing the traits number seems to further increase time and heap usage.
4. Inheritance depth: if `X*` do not directly inherit from `Implicits` but via other traits (e.g. `X1 <: A1 <: B1 <: ... <: Implicits` instead of `X1 <: Implicits`), this also seems to increase the time and space usage.
5. The number of type parameters to the implicits must be big enough but I did not notice a significant time-space increase beyond 22.
6. If you comment out `object x`, the behavior disappears.
7. If you comment out `package foo`, the behavior disappears. You can bring `object x` under `object Test` for the behavior to reappear, however, it seems it is a bit weaker that way.
8. The type parameters to the implicits must have context bounds – without the context bounds, the behavior disappears.

The described scenario can be encountered in practice e.g. when generating typeclasses for tuples. You can easily end up with a few dozen synthetic implicits that way, as was done in upickle.

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