Empty package is available across files to named packages

[som-snytt]

Compiler version

Scala compiler version 3.0.3-RC1-bin-SNAPSHOT-git-7899462 -- Copyright 2002-2021, LAMP/EPFL

Minimized code

A file with definitions in empty package:

def f = 42

class C

Another file with definitions in named package:

class D2 extends C

package p {
  class D extends C

  @main def test = println((new D, new D2))
}

but it doesn't compile without the D2

package p {
  class D extends C

  @main def test = println(new D)
}

Output

without the "enabling" D2 to "open" the empty package

➜  ~/projects/dotty/bin/scalac -d /tmp -Vprint:typer  mt2.scala mt.scala
-- [E006] Not Found Error: mt.scala:5:18 --------------------------------------------------------------------------------
5 |  class D extends C
  |                  ^
  |                  Not found: type C

Expectation

File visibility of empty package defs in named package, per #7891

Not magically visible empty package across compilation units, such as C visible when D2 is defined.

Empty package defs available to empty package anywhere and anything in same file.

[som-snytt]

It looks like the "extra" definition could also be a second package, not just a top-level def.

[Kordyjan]

The visibility of definitions from the empty package is still an unsolved issue. This one will probably be solved together with #7891, you have mentioned.