Compilation loop when companion object is in other file than class

[pikinier20]

Minimized code

One file:

package example.reproduction

class Reproduction

Second file:

package example.reproduction

object Reproduction

Output

Looped compilation - repeated message about compiling 2 sources from ...

Expectation

I think this code is correct and should compile correctly

[abgruszecki]

I retested this on master - it seems that instead of looping, we emit a mysterious error message:

-- [E006] Not Found Error: A2.scala:3:0 ----------------------------------------
3 |object Reproduction
  |^
  |Not found: type Reproduction$

longer explanation available when compiling with `-explain`
1 error found

We should fix this to be explicit about why we refuse to compile the above definitions.