Swift Playground compiler crashes when arbitrary function is annotated with @inlinable

Number:rdar://FB7719603 Date Originated:5/31/2020
Status:Open Resolved:
Product:Swift Playground Product Version:
Classification:Incorrect/Unexpected behavior Reproducible:Always
* Please describe the issue:
When using Swift Playgrounds app (both on macOS and iPad), the application fails to run playground page if it contains function annotated with @inlinable. The app itself won't crash but the compiler will. Console.app on macOS is full of crash reports. It's hard to find why the page won't run because playgrounds will not mark problematic part of the code.
Please list the steps you took to reproduce the issue:
Create an empty playground on iPad or macOS and write function annotated with @inlinable, for example:

func thisShouldWork() {


Then click on 'Run My Code'

* What did you expect to happen?
The app will compile and run given code.

* What actually happened?
The compiler fails to compile the code and crashes. The app continues to run and shows 'There was a problem running this page.' error modal. Note that annotating variables inside struct works and compiles.


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