Implement correct capture check for lazy vals #21601
Description
Compiler version
Minimized example
def f(c: T^, d: T^) =
lazy val x: T^{c} = d; c
val f = () => xOutput
Compiling this with -Xprint:cc gives:
package <empty> {
@SourceFile("tests/new/test.scala") class T() extends Object() {}
final lazy module val test$package: test$package = new test$package()
@SourceFile("tests/new/test.scala") final module class test$package() extends
Object() {
private[this] type $this = test$package.type
private def writeReplace(): AnyRef =
new scala.runtime.ModuleSerializationProxy(classOf[test$package.type])
def f(c: T^, d: T^): Unit =
{
lazy val x: T^{c} =
{
d
c
}
val f: () ->{x} (ex$1: caps.Exists) -> T^{x} =
{
def $anonfun(): T^{x} = x
closure($anonfun)
}
()
}
}
}Expectation
f should also capture d, but this is not recorded.
Generally, we have spent no thought so far how to capture check lazy vals, and it looks interesting. Maybe someone wants to pick that up?