From 0b884db73439fa7036cbfe9bc88a2ec3701a05a2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Johannes=20Wei=C3=9F?= <johannesweiss@apple.com>
Date: Mon, 16 Jan 2017 19:37:06 +0000
Subject: [PATCH] don't hold references to unowned DispatchData objects
 (SR-3628)

(cherry picked from commit dac881a0ec3e41b669aac1f2d686e90e665f08ae)
---
 src/swift/DispatchStubs.cc |  6 ++++++
 src/swift/Wrapper.swift    | 12 +++++++-----
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/src/swift/DispatchStubs.cc b/src/swift/DispatchStubs.cc
index a3629c60d..c81768ab8 100644
--- a/src/swift/DispatchStubs.cc
+++ b/src/swift/DispatchStubs.cc
@@ -165,6 +165,12 @@ _swift_dispatch_release(dispatch_object_t obj) {
   dispatch_release(obj);
 }
 
+SWIFT_CC(swift) DISPATCH_RUNTIME_STDLIB_INTERFACE
+extern "C" void
+_swift_dispatch_retain(dispatch_object_t obj) {
+  dispatch_retain(obj);
+}
+
 // DISPATCH_RUNTIME_STDLIB_INTERFACE
 // extern "C" dispatch_queue_t
 // _swift_apply_current_root_queue() {
diff --git a/src/swift/Wrapper.swift b/src/swift/Wrapper.swift
index 34ccc1b1f..ece006d6b 100644
--- a/src/swift/Wrapper.swift
+++ b/src/swift/Wrapper.swift
@@ -188,7 +188,6 @@ extension DispatchSource : DispatchSourceProcess,
 
 internal class __DispatchData : DispatchObject {
 	internal let __wrapped:dispatch_data_t
-	internal let __owned:Bool
 
 	final internal override func wrapped() -> dispatch_object_t {
 		return unsafeBitCast(__wrapped, to: dispatch_object_t.self)
@@ -196,13 +195,13 @@ internal class __DispatchData : DispatchObject {
 
 	internal init(data:dispatch_data_t, owned:Bool) {
 		__wrapped = data
-		__owned = owned
+		if !owned {
+			_swift_dispatch_retain(unsafeBitCast(data, to: dispatch_object_t.self))
+		}
 	}
 
 	deinit {
-		if __owned {
-			_swift_dispatch_release(wrapped())
-		}
+		_swift_dispatch_release(wrapped())
 	}
 }
 
@@ -335,3 +334,6 @@ internal enum _OSQoSClass : UInt32  {
 
 @_silgen_name("_swift_dispatch_release")
 internal func _swift_dispatch_release(_ obj: dispatch_object_t) -> Void
+
+@_silgen_name("_swift_dispatch_retain")
+internal func _swift_dispatch_retain(_ obj: dispatch_object_t) -> Void