[SR-8771] Object deallocation in Xcode 10 Playground does not work

[DevAndArtist]

Previous ID	SR-8771
Radar	rdar://problem/44513925
Original Reporter	@DevAndArtist
Type	Bug

Environment

Xcode 10 GM

Additional Detail from JIRA

Votes	0
Component/s	Xcode Playground Support
Labels	Bug
Assignee	None
Priority	Medium

md5: ca7b422a0aafdb7e1527b0c4b35306bd

Issue Description:

Playgroud does proceed with deallocation of objects when expected in Xcode 10 GM.

class Ref {
  weak var obj: Obj?
}

class Obj {
  deinit {
    print("deinit")
  }
}

var obj: Obj? = Obj() // Never deallocates in Xcode 10 Playground
let ref = Ref()
ref.obj = obj
obj = nil

Discussion in the forums:

https://forums.swift.org/t/is-this-a-swift-4-2-regression-object-not-deallocating/16136

[DevAndArtist]

Swift Sync System create

[DevAndArtist]

@belkadan was it okay for me to call the sync system? And do I always need to add the link in order for it to trigger? I did it the first time ever, but only because I've seen it on every ticket that creates a rdar.

[belkadan]

It's better for you not to, cause if there's already a Radar tracking the same issue we'd rather link the existing one. (I also think we'd prefer if non-Apple people don't use it in general, just for corporate / open-source boundary reasons.)

[DevAndArtist]

Thanks for clarification on that.