The new Xcode 15.3 Release Candidate produces errors with strict concurrency checking that the usual pattern of using OSLog with a static property like static let logger = Logger(...) is not safe.
"Static property 'logger' is not concurrency-safe because it is not either conforming to 'Sendable' or isolated to a global actor; this is an error in Swift 6"
Is Logger thread safe and just not marked Sendable? Would it be "safe" to use nonisolated(unsafe) static let logger = Logger(...)?
Logger should be sendable. Under the covers, it’s an immutable struct with a single OSLog property, and that in turn is just a wrapper around the C os_log_t which is definitely thread safe.
We already have a bug on file requesting that it be marked sendable (r. 122467426). Sadly, the fix didn’t make Xcode 15.3.
In the meantime, I think it’s fine for you to suppress the warning with that annotation. I also recommend that you add this:
#if swift(>=6.0)
#warning("Reevaluate whether this decoration is necessary.")
#endif
to remind you to revisit this when Swift 6 lands.
IMPORTANT I’m not promising that this’ll be fixed in Swift 6 [1], just that it makes sense to reevaluate it then.
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Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"
[1] Because that’s a statement about The Future™, and I can’t predict that.
