@main methods can't be experimental

[prolativ]

Compiler version

3.1.1-RC1

Minimized code

import annotation.experimental

@main
@experimental
def run(): Unit = {}

Output

[error] method run is marked @experimental and therefore may only be used in an experimental scope.
[error] @main
[error] ^

Expectation

As the code below compiles successfully

import annotation.experimental

object Main:
  @experimental
  def main(args: Array[String]): Unit = {}

I would expect the variant with @main @experimental to work as well unless for some reason we decide it would be better not to have experimental main methods at all, in which case we should disallow marking main methods in objects as @experimental.

@odersky @smarter what do you think?

[smarter]

Sounds like @experimental isn't copied to the method on the generated class.