Based on the OpenCB failure dotty-cps-async/dotty-cps-async - build logs and torrentdam/bittorrent - build logs
Compiler version
3.9.0-RC4
Bisect points to 32a04c8 / #25960
Compiles fine in 3.8.4
Minimized code
Original snippet (cats-effect-cps):
//> using dep org.typelevel::cats-effect-cps:0.5.0
//> using dep org.typelevel::cats-effect:3.7.0
import cats.effect.IO
import cats.effect.cps.*
def program: IO[Int] = async[IO] {
val x = IO.pure(1).await
x + 1
}Self contained minimization
trait Ctx[F[_]]
trait TryCtx[F[_]] extends Ctx[F]
trait Monad[F[_]]:
type Context <: Ctx[F]
def pure[T](t: T): F[T]
def apply[T](op: Context => F[T]): F[T]
object Monad:
type Aux[F[_], C <: Ctx[F]] = Monad[F] { type Context = C }
trait TryMonad[F[_]] extends Monad[F]:
type Context <: TryCtx[F]
class TryBody[F[_]] extends TryCtx[F]
trait TryInstance[F[_]] extends TryMonad[F]:
type Context = TryBody[F]
def apply[T](op: Context => F[T]): F[T] = op(TryBody())
class InferAsyncArg[F[_], C <: Ctx[F]](using val am: Monad.Aux[F, C]):
transparent inline def apply[T](inline expr: C ?=> T): F[T] =
am.apply(ctx => am.pure(expr(using ctx)))
transparent inline def async[F[_]](using am: Monad[F]) =
new InferAsyncArg(using am)
case class IO[A](value: A)
implicit def ioTryMonad: TryMonad[IO] = new TryMonad[IO] with TryInstance[IO]:
def pure[T](t: T) = IO(t)
def program: IO[Int] = async[IO] {
1 + 1
}Output
[error] ./test.scala:50:24
[error] Found: (ctx : InferAsyncArg_this.am.Context)
[error] Required: InferAsyncArg[IO, ? <: TryCtx[IO]]#C
Error compiling project (Scala 3.9.0-RC4, JVM (25))
Expectation
Most likely should continue to compile
Based on the OpenCB failure dotty-cps-async/dotty-cps-async - build logs and torrentdam/bittorrent - build logs
Compiler version
3.9.0-RC4
Bisect points to 32a04c8 / #25960
Compiles fine in 3.8.4
Minimized code
Original snippet (cats-effect-cps):
Self contained minimization
Output
Expectation
Most likely should continue to compile