Disable enum cases as protocol witnesses. #35842
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There is a serious bug in the implementation. swiftlang#35838 fixes this in main, but might have side effects that are more than we want to risk for Swift 5.4. rdar://73855052
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| @swift-ci Please test |
slavapestov requested changes Feb 9, 2021
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This feature shipped in 5.3 so we can't remove it now. I would just cherry pick the real fix into 5.4.
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Explanation: There is a serious miscompilation bug in the code generation for enum cases as protocol witnesses. There is a fix in #35838, but that fix affects a fairly low level of SIL type lowering that could have unforeseen knock on effects, so I don't want to risk the stability of 5.4. It is safer to disable this new feature in the meantime.
Scope: Removes a new feature from the 5.4 branch.
Issue: rdar://73855052
Risk: Low, removes a new feature.
Testing: Swift CI