21386259: -[UIApplication canOpenURL:] deadlock

[openradar-mirror]

Description

I just experienced a deadlock in -[UIApplication canOpenURL:] with the following backtrace:

• thread 22108400: Swift 2.0b4: Allow if let and guard let to assign to self in failable value type initializers #1: tid = 0x23e07, 0x000000019a998b08 libsystem_kernel.dylib`semaphore_wait_trap + 8, queue = 'com.apple.main-thread', stop reason = signal SIGSTOP
  • frame #0: 0x000000019a998b08 libsystem_kernel.dylibsemaphore_wait_trap + 8 frame #1: 0x00000001013f2cd8 libdispatch.dylib_dispatch_semaphore_wait_slow + 244
    frame 22108390: Swift 2.0b4: Allow assignment of nil to self in failable initializers to indicate failure #2: 0x000000019aaa706c libxpc.dylibxpc_connection_send_message_with_reply_sync + 204 frame #3: 0x0000000187e71678 MobileCoreServices_LSCanOpenURL + 96
    frame 22108127: Apple Music: CarPlay does not show the For You Playlists #4: 0x0000000187e776a8 MobileCoreServices-[LSApplicationWorkspace isApplicationAvailableToOpenURL:error:] + 332 frame #5: 0x000000018a7bf784 UIKit-[UIApplication _applicationProxyForURL:publicURLsOnly:] + 100
    frame 22108095: Changing account in Music app requires force-quit #6: 0x000000018a79601c UIKit-[UIApplication _canOpenURL:publicURLsOnly:] + 256 frame #7: 0x000000018a7bf958 UIKit-[UIApplication canOpenURL:] + 236
    frame 22107434: Providing Generic Generator for protocol intermittently crashes compiler #8: 0x000000010010f3d8 Where To`-[UIApplication(self=0x000000015ed7bb90, _cmd=0x000000018ae3cdb3, url=0x00000001660dcc70) myCanOpenURL:] + 684 at UIApplication+Additions.m:61

The app waits forever in this backtrace and is completely unresponsive.

The call was made right after putting the app into the foreground.

Product Version: 9.0 beta 1
Created: 2015-06-15T18:32:20.004180
Originated: 2015-06-15T20:32:00
Open Radar Link: http://www.openradar.me/21386259