Error: '@backDeployed' requires that initializer 'init(cString:)' have a body

Development Standard Library
1

Hi! I have a small diff on Standard Library and I am attempting to build a toolchain for testing my changes.

I checked out swift and followed the steps in GettingStarted.md to clone the dependencies. When I try and follow the steps from README.md to build the toolchain I see these errors:

error: '@backDeployed' requires that initializer 'init(cString:)' have a body
1415 |   @available(*, deprecated, renamed: "init(platformString:)")
1416 |   public init(cString: Swift.UnsafePointer<Swift.CChar>)
1417 |   @backDeployed(before: macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0)
     |    `- error: '@backDeployed' requires that initializer 'init(cString:)' have a body
1418 |   @available(*, deprecated, renamed: "init(platformString:)")
1419 |   @available(visionOS, unavailable, renamed: "init(platformString:)")

It looks like there are 18 of those errors when attempting to build the toolchain.

Any ideas what to do about that? I couldn't find any open tasks in the repo tracking a similar error on backDeployed.

Is there a better way for me to build and test local changes on Standard Library with a toolchain build?

2

Just in case it makes any difference I see some clues that these errors are related to building for XROS.platform and XRSimulator.platform.

I'm also building from macOS 15.5.

3

Actually it looks like this is also failing on CI with the same error:

4

It looks like build-toolchain --macos-only still works for now locally.

5

not sure if it's related, but a pair of PRs were put up recently to fix something involving back deployment and availability. seems like you might have found a workaround, but also could try applying the patch locally.

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