Insight needed for `Equatable` with Default MainActor Isolation

Using Swift
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1

I thought the following would have been resolved with Pull Request #82383

I’m using default actor isolation of MainActor as well as approachable concurrency. But when I have a protocol conforming to Equatable, I still need to use @MainActor on conforming types:

protocol P1: Equatable { }

struct S1: P1 { }
// Error: Conformance of 'S1' to protocol 'P1' crosses into main actor-isolated code an can cause data races

struct S1Workaround: @MainActor P1 { }	// OK

// Another potential workaround if `Equatable` conformance can be moved to the conforming type.
protocol P2 { }

struct S2: Equatable, P2 { }	// OK

I filed Issue 83610 last week but not responses yet. Thus, posting here to see if anyone has insights to include if this is perhaps working as expected. Thank you.

2

@Douglas_Gregor Any insights here would be most appreciated. I’m trying to figure out if this is an issue with the Swift compiler, or a legitimate case of still having to use @MainActor when default isolation is MainActor. Thank you.