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// RUN: %target-build-swift %s %import-libdispatch -o %t_binary
// RUN: %target-codesign %t_binary
// RUN: %target-run %t_binary
// REQUIRES: executable_test
// REQUIRES: stress_test
// REQUIRES: libdispatch
// UNSUPPORTED: threading_none
import StdlibUnittest
import Dispatch
let iterations = 200_000
class Thing {}
class WBox<T: AnyObject> {
weak var wref: T?
init(_ ref: T) { self.wref = ref }
init() { self.wref = nil }
}
let WeakReferenceRaceTests = TestSuite("WeakReferenceRaceTests")
func forwardOptional<T>(_ t: T!) -> T {
return t!
}
WeakReferenceRaceTests.test("class instance property (copy)") {
let q = DispatchQueue(label: "", attributes: .concurrent)
// Capture a weak reference via its container object.
// https://github.com/apple/swift/issues/42814
for i in 1...iterations {
let box = WBox(Thing())
let closure = {
let nbox = WBox<Thing>()
nbox.wref = box.wref
_blackHole(nbox)
}
q.async(execute: closure)
q.async(execute: closure)
}
q.async(flags: .barrier) {}
}
WeakReferenceRaceTests.test("class instance property (load)") {
let q = DispatchQueue(label: "", attributes: .concurrent)
// Capture a weak reference via its container object.
// https://github.com/apple/swift/issues/42814
for i in 1...iterations {
let box = WBox(Thing())
let closure = {
if let ref = box.wref {
_blackHole(ref)
}
}
q.async(execute: closure)
q.async(execute: closure)
}
q.async(flags: .barrier) {}
}
WeakReferenceRaceTests.test("direct capture (copy)") {
let q = DispatchQueue(label: "", attributes: .concurrent)
// Capture a weak reference directly in multiple closures
for i in 1...iterations {
weak var wref = Thing()
let closure = {
let nbox = WBox<Thing>()
nbox.wref = wref
_blackHole(nbox)
}
q.async(execute: closure)
q.async(execute: closure)
}
q.async(flags: .barrier) {}
}
WeakReferenceRaceTests.test("direct capture (load)") {
let q = DispatchQueue(label: "", attributes: .concurrent)
// Capture a weak reference directly in multiple closures
for i in 1...iterations {
weak var wref = Thing()
let closure = {
if let ref = wref {
_blackHole(ref)
}
}
q.async(execute: closure)
q.async(execute: closure)
}
q.async(flags: .barrier) {}
}
runAllTests()
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