The `@section` and `@used` attributes are available in Swift 6.3 and later. See [SE-0492][1]. Prior to 6.3, these were available as `@_section` and `@_used`, however those require enabling the `SymbolLinkageMarkers ` experimental feature. [1]: https://github.com/swiftlang/swift-evolution/blob/main/proposals/0492-section-control.md