Scala 3: Zinc does not fully propagate changes to inline methods

[informarte]

versions

Scala 3.0.1, Mill 0.9.9, Zinc 1.5.5

steps

Put the following objects into separate files:

object A {
  inline def f(x: Int) = x * 2
  def main(args: Array[String]): Unit = {
    println(f(10))
  }
}

object B {
  inline def g(x: Int) = A.f(x) * 2
  def main(args: Array[String]): Unit = {
    println(g(10))
  }
}

object C {
  inline def h(x: Int) = B.g(x) * 2
  def main(args: Array[String]): Unit = {
    println(h(10))
  }
}

Compile and run C.main; the output is 80.

problem

Now change the constant in A.f to 4 and recompile. Only 2 files get recompiled and the output of C.main is still 80.

expectation

After changing A.f, all files get recompiled and the output of C.main is correct.

notes

There seems to be now way to disable inlining in Scala 3. Hence it is very important that incremental compilation produces a correct result when an inlined method was changed. At the very least, a full rebuild should be triggered.

[smarter]

Duplicate of scala/scala3#11861 (incremental compilation in scala 3 is implemented in the compiler repository, not in zinc's repository) Also note that there's an open pr for this issue: scala/scala3#12931

[informarte]

Good to know, thanks.