// RUN: not --crash %target-swift-frontend %s -emit-ir // REQUIRES: OS=macosx import Foundation import CoreData // Does not segfault @available(macOS 10.12, *) class Foo: NSObject, NSFetchedResultsControllerDelegate { override init() { super.init() } @nonobjc func controllerWillChangeContent(_ controller: NSFetchedResultsController) { } } // Segfaults @available(macOS 10.12, *) class Bar: NSObject { override init() { super.init() } } @available(macOS 10.12, *) extension Bar: NSFetchedResultsControllerDelegate { @nonobjc func controllerWillChangeContent(_ controller: NSFetchedResultsController) { } }