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Summary:
Bridging an NSArray from Objective-C to a typed array in Swift can cause memory leaks to be reported in Instruments. Changing the code from a typed array to an NSArray fixes the leak, but only when each member in the array is cast individually:

```
array.map { $0 as? ElementType}.filter { $0 != nil }.flatMap { $0 }
```

Happens when either -O (fast) or -O -whole-module-optimization compiler flags are enabled.

Steps to Reproduce:
1. Download the attached project zip and unzip.
2. Open in Xcode and select a simulator or device.
3. Profile the app in Instruments, selecting the 'Leaks' instrument if prompted (either Simulator or Device).
4. Change `#if 1` to `#if 0` on line 15 in `AppDelegate.m`.
5. Profile the app again.

Expected Results:
There shouldn’t be any memory leaks, regardless of whether typed bridging is used.

Actual Results:
Instruments detects a memory leak when bridging to typed array from Objective-C. (see attached screenshot)

Version:
Xcode Version 7.3.1 (7D1014)
OS X 10.11.6

Notes:


Configuration:
Apple Swift version 2.2 (swiftlang-703.0.18.8 clang-703.0.31)
Target: x86_64-apple-macosx10.9

SwiftArrayBridgingLeakExample.zip - configuration file has been successfully uploaded.

Attachments:
'Screenshot 2016-08-18 11.14.40.png' and 'SwiftArrayBridgingLeakExample.zip' were successfully uploaded.