# 'InlineArray' is only available in macOS 26.0 or newer **URL:** \ **Category:** Using Swift\ **Tags:** inlinearray\ **Created:** [January 13, 2026, 5:19am UTC](https://forums.swift.org/t/inlinearray-is-only-available-in-macos-26-0-or-newer/84103 "2026-01-13T05:19:55Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![ibex](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/ibex/32/30439_2.png) [@ibex](https://forums.swift.org/u/ibex)\ **Post date:** [January 13, 2026, 5:19am UTC](https://forums.swift.org/t/inlinearray-is-only-available-in-macos-26-0-or-newer/84103/1 "2026-01-13T05:19:55Z")
I am using `Xcode 26.2` on a Mac (`15.7.3 (24G419)`) with Intel cores. I am unable use `InlineArray` for some reason. ```swift 'InlineArray' is only available in macOS 26.0 or newer ``` What is the reason? ---
**Author:** ![vanvoorden](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/vanvoorden/32/33619_2.png) [@vanvoorden](https://forums.swift.org/u/vanvoorden)\ **Post date:** [January 13, 2026, 5:25am UTC](https://forums.swift.org/t/inlinearray-is-only-available-in-macos-26-0-or-newer/84103/2 "2026-01-13T05:25:51Z")
> [@ibex](#): > > ```swift > 'InlineArray' is only available in macOS 26.0 or newer > > ``` This sounds correct? `InlineArray` requires `SwiftStdlib 6.2`: > Which requires macOS 26: > ---
**Author:** ![ibex](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/ibex/32/30439_2.png) [@ibex](https://forums.swift.org/u/ibex)\ **Post date:** [January 13, 2026, 6:19am UTC](https://forums.swift.org/t/inlinearray-is-only-available-in-macos-26-0-or-newer/84103/3 "2026-01-13T06:19:54Z")
> [@vanvoorden](#): > > Which requires macOS 26: Thank you, but would you know the specific reason? I would understand the requirement if it were to do with the concurrency system which might have a dependency on Apple silicon cores, but for a data structure I am baffled by this requirement. ---
**Author:** ![vanvoorden](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/vanvoorden/32/33619_2.png) [@vanvoorden](https://forums.swift.org/u/vanvoorden)\ **Post date:** [January 13, 2026, 6:26am UTC](https://forums.swift.org/t/inlinearray-is-only-available-in-macos-26-0-or-newer/84103/4 "2026-01-13T06:26:51Z")
> [@ibex](#): > > I would understand the requirement if it were to do with the concurrency system which might have a dependency on Apple silicon cores, but for a data structure I am baffled by this requirement. I don't actually think there is a lot of precedent here that new data structures should — or _can_ — be backdeployed. > [@Add @ArrayBuilder to the standard library](https://forums.swift.org/t/add-arraybuilder-to-the-standard-library/83811/12): > > The normal course of events, IIUC, is that new functions and methods can be freely back-deployed if they depend only on other earlier-available entrypoints, but types, protocols, and conformances _cannot_ be back-deployed. Substantial efforts and design decisions were put in to make such back-deployment possible for the Concurrency library. The `Span` types are backdeployable but AFAIK it was a lot of effort to get that working. ---
**Author:** ![David\_Smith](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/david_smith/32/37508_2.png) [@David\_Smith](https://forums.swift.org/u/David_Smith)\ **Post date:** [January 13, 2026, 7:02am UTC](https://forums.swift.org/t/inlinearray-is-only-available-in-macos-26-0-or-newer/84103/5 "2026-01-13T07:02:37Z")
> [@ibex](#): > > Thank you, but would you know the specific reason? In general, new types are extraordinarily difficult to back port, regardless of what they do. New functions/methods are much much easier. Among other issues, system libraries adopting them internally and then clients bringing their own copy and trying to pass into the library would lead to problems. ---
**Author:** ![CrystDragon](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/crystdragon/32/10461_2.png) [@CrystDragon](https://forums.swift.org/u/CrystDragon)\ **Post date:** [January 13, 2026, 7:47am UTC](https://forums.swift.org/t/inlinearray-is-only-available-in-macos-26-0-or-newer/84103/6 "2026-01-13T07:47:49Z")
In addition to what David has said, `InlineArray` also relies on the language feature of "Integer Generic Parameters", which already requires a Swift 6.2 runtime in the first place. Related thread: [Using InlineArray on macOS](https://forums.swift.org/t/using-inlinearray-on-macos/81492) ---
**Author:** ![tim1724](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/tim1724/32/450_2.png) [@tim1724](https://forums.swift.org/u/tim1724)\ **Post date:** [January 14, 2026, 7:04pm UTC](https://forums.swift.org/t/inlinearray-is-only-available-in-macos-26-0-or-newer/84103/7 "2026-01-14T19:04:03Z")
> [@ibex](#): > > Thank you, but would you know the specific reason? On Apple platforms the Swift Standard Library is part of the system software. So you're stuck with whatever version shipped with a particular version of the operating system. (I suppose Apple could update it in a software update, but they generally don't.) ---
**Author:** ![matthewruzzi](https://avatars.discourse-cdn.com/v4/letter/m/b782af/32.png) [@matthewruzzi](https://forums.swift.org/u/matthewruzzi)\ **Post date:** [January 14, 2026, 10:50pm UTC](https://forums.swift.org/t/inlinearray-is-only-available-in-macos-26-0-or-newer/84103/8 "2026-01-14T22:50:11Z")
It used to be bundled with the app itself. Is there still any way to do this? ---
**Author:** ![tim1724](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/tim1724/32/450_2.png) [@tim1724](https://forums.swift.org/u/tim1724)\ **Post date:** [January 14, 2026, 10:59pm UTC](https://forums.swift.org/t/inlinearray-is-only-available-in-macos-26-0-or-newer/84103/9 "2026-01-14T22:59:45Z")
Not for a long time now. Not since Apple's system libraries started using Swift. They need the version Apple ships, and you can't load two copies of the standard library into the same process, so if you link against just about any Apple library (aside from maybe libSystem and other C stuff) you wouldn't be able to use any version of the Swift Standard Library aside from the system one. Thus the option to use your own was removed a long time ago, as it's not useful for much besides perhaps command line utilities (as anything GUI will pull in the system's copy of the Standard Library) ---
**Author:** ![David\_Smith](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/david_smith/32/37508_2.png) [@David\_Smith](https://forums.swift.org/u/David_Smith)\ **Post date:** [January 14, 2026, 11:35pm UTC](https://forums.swift.org/t/inlinearray-is-only-available-in-macos-26-0-or-newer/84103/10 "2026-01-14T23:35:50Z")
> [@tim1724](#): > > libSystem libsystem actually indirectly links libswiftCore now it turns out. iirc the dependency chain is libsystem -\> libdispatch -\> libobjc -\> libswiftCore ---
**Author:** ![tim1724](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/tim1724/32/450_2.png) [@tim1724](https://forums.swift.org/u/tim1724)\ **Post date:** [January 15, 2026, 1:56am UTC](https://forums.swift.org/t/inlinearray-is-only-available-in-macos-26-0-or-newer/84103/11 "2026-01-15T01:56:27Z")
> [@David\_Smith](#): > > libsystem actually indirectly links libswiftCore now it turns out Well, that pretty conclusively rules out using your own copy of the Swift standard library for anything on modern macOS. You can't even make system calls without libSystem (at least not safely, as the Go maintainers learned the hard way)