When using build tools 14.3 everything works, but when using 15.1 the following piece of code fails to compile when BUILD_LIBRARY_FOR_DISTRIBUTION is set to YES.
public protocol Test<PrimaryType> {
associatedtype PrimaryType
func give() -> PrimaryType
}
public typealias Concrete = Test<Int> & AnyObject
public protocol Factory {
func concrete() -> any Concrete
}
It looks like a bug was introduced in the new build tools version.
The output error is:
/Users/{redacted}/Library/Developer/Xcode/DerivedData/TestPat-bhxphcvnfxvnqqawqjiikabafbhb/Build/Intermediates.noindex/TestPat.build/Release-iphoneos/PatTest.build/Objects-normal/arm64/PatTest.swiftinterface:21:26: error: non-protocol, non-class type 'Test<Int>' cannot be used within a protocol-constrained type
func concrete() -> any PatTest.Test<Swift.Int> & Swift.AnyObject
^
/Users/{redacted}/Library/Developer/Xcode/DerivedData/TestPat-bhxphcvnfxvnqqawqjiikabafbhb/Build/Intermediates.noindex/TestPat.build/Release-iphoneos/PatTest.build/Objects-normal/arm64/PatTest.swiftinterface:1:1: error: failed to verify module interface of 'PatTest' due to the errors above; the textual interface may be broken by project issues or a compiler bug
// swift-interface-format-version: 1.0
^
** BUILD FAILED **
excerpt:
error: non-protocol, non-class type 'Test<Int>'
cannot be used within a protocol-constrained type
func concrete() -> any PatTest.Test<Swift.Int> & Swift.AnyObject
^
I would expect this should compile with no issues.