Swift 5.7 concurrency regression for top-level code

Using Swift
1

For Swift 5.7, I'm getting odd behaviour when I call Task.init at the top-level. Here's an executable Swift package's main.swift (Repository for source code):

actor CounterActor {
	var count = 0
	var maximum = 0
}

let counterActor = CounterActor()

Task.init {
	await print(counterActor.count)
	await print(counterActor.maximum)
}

Thread.sleep(forTimeInterval: 5)

It outputs nothing from swift run no matter how much time we sleep for.

If we wrap the top-level code in a function, then it outputs quickly:

actor CounterActor { /* same as before */ }

func f() {
	let counterActor = CounterActor()
	
	Task {
		await print(counterActor.count)
		await print(counterActor.maximum)
	}
	Thread.sleep(forTimeInterval: 0.5)
}

f()

Thread.sleep(forTimeInterval: 0.1)

Am I doing something wrong or is this behaviour a regression? (It works as I would expect with Xcode 13.3.1)

Environment:

$ swift --version
swift-driver version: 1.55.1 Apple Swift version 5.7 (swiftlang-5.7.0.113.202 clang-1400.0.16.2)
Target: arm64-apple-macosx12.0

OS: macOS Monterey 12.4
Chip: Apple M1 Max

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