Crash when an NSDictionary<NSString *, NSError *> is attempted to bridge to Swift

Number:rdar://39349762 Date Originated:April 11th, 2018
Status:None Resolved:
Product:Developer Tools Product Version:Xcode Version 9.3 (9E145)
Classification:Crash Reproducible:Always
When an Objective-C API uses an `NSDictionary<NSString *, NSError *> *` object either as a return type, parameter, or block parameter, the bridging that takes place to and from the Swift `Error` type will cause the app to crash.
If an API simply uses `NSError *` type, the bridging produces useable objects both ways with no crashing.

Steps to Reproduce:
Use the attached project and run, you will get through the plain error tests but crash on any of the dictionary tests

Expected Results:
NSError bridging within a Dictionary should produce the same sort of objects we get from the plain error examples

Actual Results:
NSError bridging within a Dictionary crashes or produces objects which crash when accessing NSError properties such as domain and code.

Xcode Version 9.3 (9E145)


Project GitHub Repository

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