发布版本中的Liker错误 - 函数签名特化<arg [2]>

Question

此代码在Debug模式（Xcode8.0）中构建良好：

private func rebuildMyClass3sForMyClassCache() {
    someWorker.fetchClass1Categories { (categories: [MyClass2]) in
        self.representedMyClass3sForMyClass1 = categories
            .flatMap { $0.class1s.sorted(by: { (a: MyClass1, b: MyClass1) -> Bool in
                return (a.priorityWithinCategory ?? 0) < (b.priorityWithinCategory ?? 0)
            })
    }
            // we want to show MyClass1 sections only for MyClass1s that actually contain MyClass3s
    .filter { $0.belongingMyClass3s.count > 0 }
}

但在构建Release时会出现链接器错误：

Showing Recent Issues   "Swift.UnsafeMutableBufferPointer.(subscript.materializeForSet : (Swift.Int) -> A).(closure #1)", referenced from:

function signature specialization <Arg[2] = Exploded> of generic specialization
<Swift.UnsafeMutableBufferPointer<MessagesExtension.MyClass1> with
Swift.UnsafeMutableBufferPointer<MessagesExtension.MyClass1> :
Swift.MutableCollection in Swift and
Swift.UnsafeMutableBufferPointer<MessagesExtension.MyClass1> :
Swift.RandomAccessCollection in Swift> of Swift._siftDown <A where A:
Swift.MutableCollection, A: Swift.RandomAccessCollection> (inout A, index : A.Index, subRange : Swift.Range<A.Index>, by : inout (A.Iterator.Element, A.Iterator.Element) -> Swift.Bool) -> () in ManageMyClass3sInteractor.o

this Question建议禁用编译器优化    在我看来，不是发布的选项。

Answer 1

原来是一个Xcode 8.0错误。

更新到Xcode 8.1解决了这个问题。