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7a8a56254a
Adding `T == Int` to
G1 := <T where T: Equatable>
gives us
G2 := <T where T == Int>
which means that if I have this substitution map for G2:
S2 := { Int }
then `SubstitutionMap::get(G1, S2)` should give me this substitution map
for G1:
S2 := { Int, [Int: Equatable] }
But it didn't, instead returning a substitution map with an invalid
conformance.
The problem is that local conformance lookup alone cannot recover
`[Int: Equatable]` in this case, because there is no "concrete
conformance requirement" `[T == Int: Equatable]` recorded anywhere
in G2.
This is of course a legacy of the GenericSignatureBuilder. It would have
been better to not drop conformance requirements made concrete. But oh
well.
Fixes https://github.com/swiftlang/swift/issues/74465
Fixes rdar://130404629.
20 lines
322 B
Swift
20 lines
322 B
Swift
// RUN: %target-swift-emit-silgen %s
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public protocol P {
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associatedtype A : Equatable
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}
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public struct G<A: Equatable>: P {}
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extension P where A == Int {
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public init(integerLiteral: Int) {
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fatalError()
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}
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}
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extension G: ExpressibleByIntegerLiteral where A == Int {}
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public func f() -> G<Int> {
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return 123
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}
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