This is not your app crashing, but the Swift compiler is crashing.
Try it again with the just-released Xcode 7.3.1 to get the latest Swift compiler version. If it still crashes, submit a bug report with the project that causes it.
If you're lucky, you can try commenting code to find the particular construct that's causing the crash, and try reworking it into a different form that the compiler doesn't choke on.
There is not a general way to fix compiler crashes like this. My recommendations:
upgrade to the latest compiler
if the problem still occurs, file a [bug report][bug], ideally with a project that reproduces the crash
look at the backtrace in the crash to see if it gives you any hints as to what’s going wrong
shuffle your code around to avoid the crash.
In your case point 1 is interesting because you have two choices:
Xcode 8 includes Swift 2.3, which is a minor update that includes compatibility with the latest SDKs.
It also includes Swift 3, which is a major language change.
For minimal disruption you should test with Swift 2.3 to see if that improves things. If not, things get trickier. Migrating to Swift 3 is a bunch of work, and there’s no guarantee that it’ll fix any specific crash.
Share and Enjoy
Quinn “The Eskimo!”
Apple Developer Relations, Developer Technical Support, Core OS/Hardware
let myEmail = "eskimo" + "1" + "@apple.com"