Open Radar

 
Summary:
As of Xcode 8.3 beta 1 (8W109m), Realm Swift no longer compiles.

This is a regression as Swift 3.1 aims to maintain source compatibility with Swift 3.0.x, and the framework compiles successfully with Swift 3.0.0, 3.0.1 and 3.0.2.

Steps to Reproduce:
1. git clone https://github.com/realm/realm-cocoa.git
2. cd realm-cocoa
3. git submodule update --init --recursive
4. git checkout a0c5399
5. open -a Xcode-8.3.app .
6. Select the "Realm Swift" scheme with "My Mac" as a build target
7. CMD-B to build

Expected Results:
RealmSwift.framework should compile successfully as it does with Xcode 8.0, 8.1 and 8.2.

Actual Results:
RealmSwift.framework fails to compile with the following errors:


/Users/jp/Projects/realm-cocoa/RealmSwift/List.swift:470:1: Type 'List<T>' does not conform to protocol '_IndexableBase'
/Users/jp/Projects/realm-cocoa/RealmSwift/List.swift:470:1: Type 'List<T>' does not conform to protocol 'RangeReplaceableCollection'
/Users/jp/Projects/realm-cocoa/RealmSwift/List.swift:470:1: Type 'List<T>' does not conform to protocol 'RandomAccessCollection'
/Users/jp/Projects/realm-cocoa/RealmSwift/List.swift:470:1: Type 'List<T>' does not conform to protocol '_RangeReplaceableIndexable'
/Users/jp/Projects/realm-cocoa/RealmSwift/List.swift:470:1: Type 'List<T>' does not conform to protocol 'Collection'
/Users/jp/Projects/realm-cocoa/RealmSwift/List.swift:470:1: Type 'List<T>' does not conform to protocol 'BidirectionalCollection'
/Users/jp/Projects/realm-cocoa/RealmSwift/List.swift:470:1: Type 'List<T>' does not conform to protocol '_BidirectionalIndexable'

Version:
Xcode 8.3 beta 1 (8W109m)

Notes:
I also tested this with top-of-trunk Swift from source (b03dfab3b45e79711217273824939c88f997a11c) which includes a fix that Joe Groff (hi Joe!) thought might have helped, but to no avail :(

See this twitter thread for not much more context: https://twitter.com/simjp/status/824685458206515200