Internal error with initialization check

[liufengyun]

Compiler version

Master

Minimized code

With -Ysafe-init:

class TestSuite:
  protected val it = new ItWord

  protected final class ItWord:
    def should(string: String) = new ItVerbString("should", string)

  private def registerTestToRun(fun: => Any): Unit = ()

  protected final class ItVerbString(verb: String, name: String):
    inline def in(testFun: => Any): Unit = registerTestToRun(testFun)

class MyTest extends TestSuite:
  it should "not cause outer select errors" in {
    assert(1 + 1 == 2)
  }

  val n = 10

Output

unexpected outerSelect, thisV = Warm(class ItVerbString,ThisRef(class MyTest),method <init>,List(Hot, Hot)), target = class MyTest, hops = 1

Expectation

The code should compile without issue. This is blocked by #15374 . It should work once #15374 is fixed.

[liufengyun]

Need to revert 73b3331 once this issue is fixed.