In Xcode 7.3.1 I perform this straigtfoward use-case resulting in crash (see below). The objective of this exercise is to add an additional tab (and view controller) to the tab controller.
1) Create New Project OSx Cocoa swift project
2) Open story board (by double-clicking storyboard)
3) Add Tab View Controller to canvas
4) Add View Controller to canvas
5) Control-drag from (3) to (4)
6) In resulting 'Relationship Segue' pop-up menu choose 'tab items'
7) Xcode crashes.
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Exception Type: EXC_CRASH (SIGABRT)
Exception Codes: 0x0000000000000000, 0x0000000000000000
Exception Note: EXC_CORPSE_NOTIFY
Application Specific Information:
ProductBuildVersion: 7D1014
UNCAUGHT EXCEPTION (NSRangeException): *** -[__NSArrayI objectAtIndex:]: index 3 beyond bounds [0 .. 2]
UserInfo: (null)
Hints:
0: Creation Backtrace for Notification Token:
0 -[_DVTNotificationReceiver initWithBlock:queue:] (in DVTFoundation)
1 -[NSNotificationCenter(DVTNSNotificationCenterAdditions) dvt_addObserverForName:object:queue:usingBlock:] (in DVTFoundation)
2 -[IBStoryboardDocumentEditor registerWithDocument] (in IDEInterfaceBuilderKit)
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