Open Radar

 
Summary:
Deleting a specific unused method in a framework that I import into a playground causes the playground execution to fail.

Steps to Reproduce:
1. Open PathMathPlay.workspace and select the playground. Note that it executes and a green cog is displayed.
2. open CogIcon.swift and delete the method named bezierPath
3. build
4. select the playground again and trigger execution. 

Expected Results:
The same results as before the deletion of the method or failed compilation 

Actual Results:
Nothing is rendered and an error is logged to console beginning with
Playground execution failed: Execution was interrupted, reason: EXC_BAD_ACCESS (code=1, address=0xe).
    * thread #1: tid = 0xdb91, 0x00007fff99cde061 libobjc.A.dylib`objc_retain + 17, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0xe)
      * frame #0: 0x00007fff99cde061 libobjc.A.dylib`objc_retain + 17
        frame #1: 0x000000010defd8b6 PathMath`protocol witness for PathMath.BezierPathType.addArcWithCenter <A : PathMath.BezierPathType>(inout PathMath.BezierPathType.Self)(C.CGPoint, radius : CoreGraphics.CGFloat, startAngle : CoreGraphics.CGFloat, endAngle : CoreGraphics.CGFloat, clockwise : Swift.Bool) -> () in conformance ObjectiveC.NSBezierPath : PathMath.BezierPathType in PathMath + 54 at BezierPath.swift:134 …

Regression:
Describe circumstances where the problem occurs or does not occur, such as software versions and/or hardware configurations.

Notes:
Provide additional information, such as references to related problems, workarounds and relevant attachments.