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Build Information

Successful build of LayoutUI, reference master (8cc8e3), with Swift 6.1 for macOS (SPM) on 31 Aug 2025 01:29:50 UTC.

Swift 6 data race errors: 10

Build Command

env DEVELOPER_DIR=/Applications/Xcode-16.3.0.app xcrun swift build --arch arm64 -Xswiftc -Xfrontend -Xswiftc -stats-output-dir -Xswiftc -Xfrontend -Xswiftc .stats -Xswiftc -strict-concurrency=complete -Xswiftc -enable-upcoming-feature -Xswiftc StrictConcurrency -Xswiftc -enable-upcoming-feature -Xswiftc DisableOutwardActorInference -Xswiftc -enable-upcoming-feature -Xswiftc GlobalActorIsolatedTypesUsability -Xswiftc -enable-upcoming-feature -Xswiftc InferSendableFromCaptures

Build Log

========================================
RunAll
========================================
Builder version: 4.67.1
Interrupt handler set up.
========================================
Checkout
========================================
Clone URL: https://github.com/k-o-d-e-n/LayoutUI.git
Reference: master
Initialized empty Git repository in /Users/admin/builder/spi-builder-workspace/.git/
From https://github.com/k-o-d-e-n/LayoutUI
 * branch            master     -> FETCH_HEAD
 * [new branch]      master     -> origin/master
HEAD is now at 8cc8e3d Last changes
Cloned https://github.com/k-o-d-e-n/LayoutUI.git
Revision (git rev-parse @):
8cc8e3d6ba1d17c258ef6d51f44db9027e928c27
SUCCESS checkout https://github.com/k-o-d-e-n/LayoutUI.git at master
========================================
ResolveProductDependencies
========================================
Resolving dependencies ...
{
  "identity": ".resolve-product-dependencies",
  "name": "resolve-dependencies",
  "url": "/Users/admin/builder/spi-builder-workspace/.resolve-product-dependencies",
  "version": "unspecified",
  "path": "/Users/admin/builder/spi-builder-workspace/.resolve-product-dependencies",
  "dependencies": [
    {
      "identity": "layoutui",
      "name": "LayoutUI",
      "url": "https://github.com/k-o-d-e-n/LayoutUI.git",
      "version": "unspecified",
      "path": "/Users/admin/builder/spi-builder-workspace/.resolve-product-dependencies/.build/checkouts/LayoutUI",
      "dependencies": [
      ]
    }
  ]
}
Fetching https://github.com/k-o-d-e-n/LayoutUI.git
[1/105] Fetching layoutui
Fetched https://github.com/k-o-d-e-n/LayoutUI.git from cache (0.74s)
Creating working copy for https://github.com/k-o-d-e-n/LayoutUI.git
Working copy of https://github.com/k-o-d-e-n/LayoutUI.git resolved at master (8cc8e3d)
warning: '.resolve-product-dependencies': dependency 'layoutui' is not used by any target
Found 0 product dependencies
========================================
Build
========================================
Selected platform:         macosSpm
Swift version:             6.1
Building package at path:  $PWD
https://github.com/k-o-d-e-n/LayoutUI.git
https://github.com/k-o-d-e-n/LayoutUI.git
{
  "dependencies" : [
  ],
  "manifest_display_name" : "LayoutUI",
  "name" : "LayoutUI",
  "path" : "/Users/admin/builder/spi-builder-workspace",
  "platforms" : [
    {
      "name" : "ios",
      "version" : "13.0"
    },
    {
      "name" : "macos",
      "version" : "10.10"
    },
    {
      "name" : "watchos",
      "version" : "6.0"
    },
    {
      "name" : "tvos",
      "version" : "13.0"
    }
  ],
  "products" : [
    {
      "name" : "LayoutUI",
      "targets" : [
        "LayoutUI"
      ],
      "type" : {
        "library" : [
          "automatic"
        ]
      }
    }
  ],
  "targets" : [
    {
      "c99name" : "LayoutUITests",
      "module_type" : "SwiftTarget",
      "name" : "LayoutUITests",
      "path" : "Tests/LayoutUITests",
      "sources" : [
        "LayoutUITests.swift"
      ],
      "target_dependencies" : [
        "LayoutUI"
      ],
      "type" : "test"
    },
    {
      "c99name" : "LayoutUI",
      "module_type" : "SwiftTarget",
      "name" : "LayoutUI",
      "path" : "Sources/LayoutUI",
      "product_memberships" : [
        "LayoutUI"
      ],
      "sources" : [
        "LayoutBuilder.swift",
        "LayoutBuilders.swift",
        "RectAccessors.swift",
        "RectBasedLayout.swift",
        "RectConstraints.swift",
        "RectLayouts.swift",
        "StackLayout.swift",
        "StackLayouts.swift",
        "SwiftUI.swift",
        "UIKit+AppKit.swift",
        "ViewBasedLayout.swift",
        "ViewConstraints.swift"
      ],
      "type" : "library"
    }
  ],
  "tools_version" : "5.6"
}
Running build ...
env DEVELOPER_DIR=/Applications/Xcode-16.3.0.app xcrun swift build --arch arm64 -Xswiftc -Xfrontend -Xswiftc -stats-output-dir -Xswiftc -Xfrontend -Xswiftc .stats -Xswiftc -strict-concurrency=complete -Xswiftc -enable-upcoming-feature -Xswiftc StrictConcurrency -Xswiftc -enable-upcoming-feature -Xswiftc DisableOutwardActorInference -Xswiftc -enable-upcoming-feature -Xswiftc GlobalActorIsolatedTypesUsability -Xswiftc -enable-upcoming-feature -Xswiftc InferSendableFromCaptures
Building for debugging...
[0/2] Write sources
[1/2] Write swift-version-2F0A5646E1D333AE.txt
[3/14] Compiling LayoutUI StackLayouts.swift
[4/14] Compiling LayoutUI ViewBasedLayout.swift
[5/14] Compiling LayoutUI UIKit+AppKit.swift
/Users/admin/builder/spi-builder-workspace/Sources/LayoutUI/UIKit+AppKit.swift:35:21: warning: main actor-isolated property 'frame' can not be referenced from a nonisolated context; this is an error in the Swift 6 language mode
 33 |     @inline(__always)
 34 |     public subscript(view: View) -> CGRect {
 35 |         get { _view.frame }
    |                     `- warning: main actor-isolated property 'frame' can not be referenced from a nonisolated context; this is an error in the Swift 6 language mode
 36 |         nonmutating set { _view.frame = newValue }
 37 |     }
/Applications/Xcode-16.3.0.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX15.4.sdk/System/Library/Frameworks/AppKit.framework/Headers/NSView.h:129:18: note: property declared here
127 | - (void)setFrameOrigin:(NSPoint)newOrigin;
128 | - (void)setFrameSize:(NSSize)newSize;
129 | @property NSRect frame;
    |                  `- note: property declared here
130 | @property CGFloat frameRotation;
131 | @property CGFloat frameCenterRotation API_AVAILABLE(macos(10.5));
/Users/admin/builder/spi-builder-workspace/Sources/LayoutUI/UIKit+AppKit.swift:36:33: warning: main actor-isolated property 'frame' can not be mutated from a nonisolated context; this is an error in the Swift 6 language mode
 34 |     public subscript(view: View) -> CGRect {
 35 |         get { _view.frame }
 36 |         nonmutating set { _view.frame = newValue }
    |                                 `- warning: main actor-isolated property 'frame' can not be mutated from a nonisolated context; this is an error in the Swift 6 language mode
 37 |     }
 38 | }
/Applications/Xcode-16.3.0.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX15.4.sdk/System/Library/Frameworks/AppKit.framework/Headers/NSView.h:129:18: note: mutation of this property is only permitted within the actor
127 | - (void)setFrameOrigin:(NSPoint)newOrigin;
128 | - (void)setFrameSize:(NSSize)newSize;
129 | @property NSRect frame;
    |                  `- note: mutation of this property is only permitted within the actor
130 | @property CGFloat frameRotation;
131 | @property CGFloat frameCenterRotation API_AVAILABLE(macos(10.5));
/Users/admin/builder/spi-builder-workspace/Sources/LayoutUI/UIKit+AppKit.swift:44:15: warning: call to main actor-isolated instance method 'sizeThatFits' in a synchronous nonisolated context; this is an error in the Swift 6 language mode
 41 |     @inlinable
 42 |     @inline(__always)
 43 |     public func fittingSize(for view: Void, with availableSize: CGSize) -> CGSize {
    |                 `- note: add '@MainActor' to make instance method 'fittingSize(for:with:)' part of global actor 'MainActor'
 44 |         _view.sizeThatFits(availableSize)
    |               `- warning: call to main actor-isolated instance method 'sizeThatFits' in a synchronous nonisolated context; this is an error in the Swift 6 language mode
 45 |     }
 46 | }
AppKit.NSControl.sizeThatFits:3:24: note: calls to instance method 'sizeThatFits' from outside of its actor context are implicitly asynchronous
1 | class NSControl {
2 | @available(macOS 10.10, *)
3 |   @MainActor open func sizeThatFits(_ size: NSSize) -> NSSize}
  |                        |- note: calls to instance method 'sizeThatFits' from outside of its actor context are implicitly asynchronous
  |                        `- note: main actor isolation inferred from inheritance from class 'NSView'
4 |
/Users/admin/builder/spi-builder-workspace/Sources/LayoutUI/UIKit+AppKit.swift:52:38: warning: main actor-isolated property 'frame' can not be referenced from a nonisolated context; this is an error in the Swift 6 language mode
 50 |     @inline(__always)
 51 |     public subscript(view: View) -> CGRect {
 52 |         get { view[keyPath: keyPath].frame }
    |                                      `- warning: main actor-isolated property 'frame' can not be referenced from a nonisolated context; this is an error in the Swift 6 language mode
 53 |         nonmutating set { view[keyPath: keyPath].frame = newValue }
 54 |     }
/Applications/Xcode-16.3.0.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX15.4.sdk/System/Library/Frameworks/AppKit.framework/Headers/NSView.h:129:18: note: property declared here
127 | - (void)setFrameOrigin:(NSPoint)newOrigin;
128 | - (void)setFrameSize:(NSSize)newSize;
129 | @property NSRect frame;
    |                  `- note: property declared here
130 | @property CGFloat frameRotation;
131 | @property CGFloat frameCenterRotation API_AVAILABLE(macos(10.5));
/Users/admin/builder/spi-builder-workspace/Sources/LayoutUI/UIKit+AppKit.swift:53:50: warning: main actor-isolated property 'frame' can not be mutated from a nonisolated context; this is an error in the Swift 6 language mode
 51 |     public subscript(view: View) -> CGRect {
 52 |         get { view[keyPath: keyPath].frame }
 53 |         nonmutating set { view[keyPath: keyPath].frame = newValue }
    |                                                  `- warning: main actor-isolated property 'frame' can not be mutated from a nonisolated context; this is an error in the Swift 6 language mode
 54 |     }
 55 | }
/Applications/Xcode-16.3.0.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX15.4.sdk/System/Library/Frameworks/AppKit.framework/Headers/NSView.h:129:18: note: mutation of this property is only permitted within the actor
127 | - (void)setFrameOrigin:(NSPoint)newOrigin;
128 | - (void)setFrameSize:(NSSize)newSize;
129 | @property NSRect frame;
    |                  `- note: mutation of this property is only permitted within the actor
130 | @property CGFloat frameRotation;
131 | @property CGFloat frameCenterRotation API_AVAILABLE(macos(10.5));
/Users/admin/builder/spi-builder-workspace/Sources/LayoutUI/UIKit+AppKit.swift:60:32: warning: call to main actor-isolated instance method 'sizeThatFits' in a synchronous nonisolated context; this is an error in the Swift 6 language mode
 57 |     @inlinable
 58 |     @inline(__always)
 59 |     public func fittingSize(for view: View, with availableSize: CGSize) -> CGSize {
    |                 `- note: add '@MainActor' to make instance method 'fittingSize(for:with:)' part of global actor 'MainActor'
 60 |         view[keyPath: keyPath].sizeThatFits(availableSize)
    |                                `- warning: call to main actor-isolated instance method 'sizeThatFits' in a synchronous nonisolated context; this is an error in the Swift 6 language mode
 61 |     }
 62 | }
AppKit.NSControl.sizeThatFits:3:24: note: calls to instance method 'sizeThatFits' from outside of its actor context are implicitly asynchronous
1 | class NSControl {
2 | @available(macOS 10.10, *)
3 |   @MainActor open func sizeThatFits(_ size: NSSize) -> NSSize}
  |                        |- note: calls to instance method 'sizeThatFits' from outside of its actor context are implicitly asynchronous
  |                        `- note: main actor isolation inferred from inheritance from class 'NSView'
4 |
[6/14] Compiling LayoutUI StackLayout.swift
/Users/admin/builder/spi-builder-workspace/Sources/LayoutUI/StackLayout.swift:37:32: warning: static property 'null' cannot be used in an '@inlinable' function because 'CoreGraphics' was not imported by this file; this is an error in the Swift 6 language mode
 35 |     @inline(__always)
 36 |     public func layout(to rect: inout CGRect, with view: Scheme.View, in source: CGRect) {
 37 |         var unionRect = CGRect.null
    |                                |- warning: static property 'null' cannot be used in an '@inlinable' function because 'CoreGraphics' was not imported by this file; this is an error in the Swift 6 language mode
    |                                `- note: The missing import of module 'CoreGraphics' will be added implicitly
 38 |         for element in data {
 39 |             var r = source
/Users/admin/builder/spi-builder-workspace/Sources/LayoutUI/StackLayout.swift:41:35: warning: instance method 'union' cannot be used in an '@inlinable' function because 'CoreGraphics' was not imported by this file; this is an error in the Swift 6 language mode
 39 |             var r = source
 40 |             scheme(element).layout(to: &r, with: view, in: source)
 41 |             unionRect = unionRect.union(r)
    |                                   |- warning: instance method 'union' cannot be used in an '@inlinable' function because 'CoreGraphics' was not imported by this file; this is an error in the Swift 6 language mode
    |                                   `- note: The missing import of module 'CoreGraphics' will be added implicitly
 42 |         }
 43 |         rect = unionRect
/Users/admin/builder/spi-builder-workspace/Sources/LayoutUI/StackLayout.swift:188:32: warning: static property 'null' cannot be used in an '@inlinable' function because 'CoreGraphics' was not imported by this file; this is an error in the Swift 6 language mode
186 |     @inline(__always)
187 |     public func layout(to rect: inout CGRect, with view: Scheme.View, in source: CGRect) {
188 |         var unionRect = CGRect.null
    |                                |- warning: static property 'null' cannot be used in an '@inlinable' function because 'CoreGraphics' was not imported by this file; this is an error in the Swift 6 language mode
    |                                `- note: The missing import of module 'CoreGraphics' will be added implicitly
189 |         reducer.reduce(source) { result, element -> SublayoutForRectCalculating<Scheme> in
190 |             let l = scheme(result, element)
[7/14] Compiling LayoutUI RectLayouts.swift
[8/14] Compiling LayoutUI RectAccessors.swift
[9/14] Compiling LayoutUI RectBasedLayout.swift
[10/14] Compiling LayoutUI RectConstraints.swift
[11/14] Compiling LayoutUI LayoutBuilder.swift
[12/14] Compiling LayoutUI LayoutBuilders.swift
[13/14] Emitting module LayoutUI
/Users/admin/builder/spi-builder-workspace/Sources/LayoutUI/StackLayout.swift:37:32: warning: static property 'null' cannot be used in an '@inlinable' function because 'CoreGraphics' was not imported by this file; this is an error in the Swift 6 language mode
 35 |     @inline(__always)
 36 |     public func layout(to rect: inout CGRect, with view: Scheme.View, in source: CGRect) {
 37 |         var unionRect = CGRect.null
    |                                |- warning: static property 'null' cannot be used in an '@inlinable' function because 'CoreGraphics' was not imported by this file; this is an error in the Swift 6 language mode
    |                                `- note: The missing import of module 'CoreGraphics' will be added implicitly
 38 |         for element in data {
 39 |             var r = source
/Users/admin/builder/spi-builder-workspace/Sources/LayoutUI/StackLayout.swift:41:35: warning: instance method 'union' cannot be used in an '@inlinable' function because 'CoreGraphics' was not imported by this file; this is an error in the Swift 6 language mode
 39 |             var r = source
 40 |             scheme(element).layout(to: &r, with: view, in: source)
 41 |             unionRect = unionRect.union(r)
    |                                   |- warning: instance method 'union' cannot be used in an '@inlinable' function because 'CoreGraphics' was not imported by this file; this is an error in the Swift 6 language mode
    |                                   `- note: The missing import of module 'CoreGraphics' will be added implicitly
 42 |         }
 43 |         rect = unionRect
/Users/admin/builder/spi-builder-workspace/Sources/LayoutUI/StackLayout.swift:188:32: warning: static property 'null' cannot be used in an '@inlinable' function because 'CoreGraphics' was not imported by this file; this is an error in the Swift 6 language mode
186 |     @inline(__always)
187 |     public func layout(to rect: inout CGRect, with view: Scheme.View, in source: CGRect) {
188 |         var unionRect = CGRect.null
    |                                |- warning: static property 'null' cannot be used in an '@inlinable' function because 'CoreGraphics' was not imported by this file; this is an error in the Swift 6 language mode
    |                                `- note: The missing import of module 'CoreGraphics' will be added implicitly
189 |         reducer.reduce(source) { result, element -> SublayoutForRectCalculating<Scheme> in
190 |             let l = scheme(result, element)
/Users/admin/builder/spi-builder-workspace/Sources/LayoutUI/SwiftUI.swift:140:16: warning: static property 'defaultValue' is not concurrency-safe because it is nonisolated global shared mutable state; this is an error in the Swift 6 language mode
138 | struct ConstrainedLayoutKey: LayoutValueKey {
139 |     @usableFromInline
140 |     static var defaultValue: Layout? = nil
    |                |- warning: static property 'defaultValue' is not concurrency-safe because it is nonisolated global shared mutable state; this is an error in the Swift 6 language mode
    |                |- note: convert 'defaultValue' to a 'let' constant to make 'Sendable' shared state immutable
    |                |- note: add '@MainActor' to make static property 'defaultValue' part of global actor 'MainActor'
    |                `- note: disable concurrency-safety checks if accesses are protected by an external synchronization mechanism
141 |     @usableFromInline
142 |     struct Layout {
/Users/admin/builder/spi-builder-workspace/Sources/LayoutUI/UIKit+AppKit.swift:35:21: warning: main actor-isolated property 'frame' can not be referenced from a nonisolated context; this is an error in the Swift 6 language mode
 33 |     @inline(__always)
 34 |     public subscript(view: View) -> CGRect {
 35 |         get { _view.frame }
    |                     `- warning: main actor-isolated property 'frame' can not be referenced from a nonisolated context; this is an error in the Swift 6 language mode
 36 |         nonmutating set { _view.frame = newValue }
 37 |     }
/Applications/Xcode-16.3.0.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX15.4.sdk/System/Library/Frameworks/AppKit.framework/Headers/NSView.h:129:18: note: property declared here
127 | - (void)setFrameOrigin:(NSPoint)newOrigin;
128 | - (void)setFrameSize:(NSSize)newSize;
129 | @property NSRect frame;
    |                  `- note: property declared here
130 | @property CGFloat frameRotation;
131 | @property CGFloat frameCenterRotation API_AVAILABLE(macos(10.5));
/Users/admin/builder/spi-builder-workspace/Sources/LayoutUI/UIKit+AppKit.swift:36:33: warning: main actor-isolated property 'frame' can not be mutated from a nonisolated context; this is an error in the Swift 6 language mode
 34 |     public subscript(view: View) -> CGRect {
 35 |         get { _view.frame }
 36 |         nonmutating set { _view.frame = newValue }
    |                                 `- warning: main actor-isolated property 'frame' can not be mutated from a nonisolated context; this is an error in the Swift 6 language mode
 37 |     }
 38 | }
/Applications/Xcode-16.3.0.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX15.4.sdk/System/Library/Frameworks/AppKit.framework/Headers/NSView.h:129:18: note: mutation of this property is only permitted within the actor
127 | - (void)setFrameOrigin:(NSPoint)newOrigin;
128 | - (void)setFrameSize:(NSSize)newSize;
129 | @property NSRect frame;
    |                  `- note: mutation of this property is only permitted within the actor
130 | @property CGFloat frameRotation;
131 | @property CGFloat frameCenterRotation API_AVAILABLE(macos(10.5));
/Users/admin/builder/spi-builder-workspace/Sources/LayoutUI/UIKit+AppKit.swift:44:15: warning: call to main actor-isolated instance method 'sizeThatFits' in a synchronous nonisolated context; this is an error in the Swift 6 language mode
 41 |     @inlinable
 42 |     @inline(__always)
 43 |     public func fittingSize(for view: Void, with availableSize: CGSize) -> CGSize {
    |                 `- note: add '@MainActor' to make instance method 'fittingSize(for:with:)' part of global actor 'MainActor'
 44 |         _view.sizeThatFits(availableSize)
    |               `- warning: call to main actor-isolated instance method 'sizeThatFits' in a synchronous nonisolated context; this is an error in the Swift 6 language mode
 45 |     }
 46 | }
AppKit.NSControl.sizeThatFits:3:24: note: calls to instance method 'sizeThatFits' from outside of its actor context are implicitly asynchronous
1 | class NSControl {
2 | @available(macOS 10.10, *)
3 |   @MainActor open func sizeThatFits(_ size: NSSize) -> NSSize}
  |                        |- note: calls to instance method 'sizeThatFits' from outside of its actor context are implicitly asynchronous
  |                        `- note: main actor isolation inferred from inheritance from class 'NSView'
4 |
/Users/admin/builder/spi-builder-workspace/Sources/LayoutUI/UIKit+AppKit.swift:52:38: warning: main actor-isolated property 'frame' can not be referenced from a nonisolated context; this is an error in the Swift 6 language mode
 50 |     @inline(__always)
 51 |     public subscript(view: View) -> CGRect {
 52 |         get { view[keyPath: keyPath].frame }
    |                                      `- warning: main actor-isolated property 'frame' can not be referenced from a nonisolated context; this is an error in the Swift 6 language mode
 53 |         nonmutating set { view[keyPath: keyPath].frame = newValue }
 54 |     }
/Applications/Xcode-16.3.0.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX15.4.sdk/System/Library/Frameworks/AppKit.framework/Headers/NSView.h:129:18: note: property declared here
127 | - (void)setFrameOrigin:(NSPoint)newOrigin;
128 | - (void)setFrameSize:(NSSize)newSize;
129 | @property NSRect frame;
    |                  `- note: property declared here
130 | @property CGFloat frameRotation;
131 | @property CGFloat frameCenterRotation API_AVAILABLE(macos(10.5));
/Users/admin/builder/spi-builder-workspace/Sources/LayoutUI/UIKit+AppKit.swift:53:50: warning: main actor-isolated property 'frame' can not be mutated from a nonisolated context; this is an error in the Swift 6 language mode
 51 |     public subscript(view: View) -> CGRect {
 52 |         get { view[keyPath: keyPath].frame }
 53 |         nonmutating set { view[keyPath: keyPath].frame = newValue }
    |                                                  `- warning: main actor-isolated property 'frame' can not be mutated from a nonisolated context; this is an error in the Swift 6 language mode
 54 |     }
 55 | }
/Applications/Xcode-16.3.0.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX15.4.sdk/System/Library/Frameworks/AppKit.framework/Headers/NSView.h:129:18: note: mutation of this property is only permitted within the actor
127 | - (void)setFrameOrigin:(NSPoint)newOrigin;
128 | - (void)setFrameSize:(NSSize)newSize;
129 | @property NSRect frame;
    |                  `- note: mutation of this property is only permitted within the actor
130 | @property CGFloat frameRotation;
131 | @property CGFloat frameCenterRotation API_AVAILABLE(macos(10.5));
/Users/admin/builder/spi-builder-workspace/Sources/LayoutUI/UIKit+AppKit.swift:60:32: warning: call to main actor-isolated instance method 'sizeThatFits' in a synchronous nonisolated context; this is an error in the Swift 6 language mode
 57 |     @inlinable
 58 |     @inline(__always)
 59 |     public func fittingSize(for view: View, with availableSize: CGSize) -> CGSize {
    |                 `- note: add '@MainActor' to make instance method 'fittingSize(for:with:)' part of global actor 'MainActor'
 60 |         view[keyPath: keyPath].sizeThatFits(availableSize)
    |                                `- warning: call to main actor-isolated instance method 'sizeThatFits' in a synchronous nonisolated context; this is an error in the Swift 6 language mode
 61 |     }
 62 | }
AppKit.NSControl.sizeThatFits:3:24: note: calls to instance method 'sizeThatFits' from outside of its actor context are implicitly asynchronous
1 | class NSControl {
2 | @available(macOS 10.10, *)
3 |   @MainActor open func sizeThatFits(_ size: NSSize) -> NSSize}
  |                        |- note: calls to instance method 'sizeThatFits' from outside of its actor context are implicitly asynchronous
  |                        `- note: main actor isolation inferred from inheritance from class 'NSView'
4 |
[14/14] Compiling LayoutUI SwiftUI.swift
/Users/admin/builder/spi-builder-workspace/Sources/LayoutUI/SwiftUI.swift:140:16: warning: static property 'defaultValue' is not concurrency-safe because it is nonisolated global shared mutable state; this is an error in the Swift 6 language mode
138 | struct ConstrainedLayoutKey: LayoutValueKey {
139 |     @usableFromInline
140 |     static var defaultValue: Layout? = nil
    |                |- warning: static property 'defaultValue' is not concurrency-safe because it is nonisolated global shared mutable state; this is an error in the Swift 6 language mode
    |                |- note: convert 'defaultValue' to a 'let' constant to make 'Sendable' shared state immutable
    |                |- note: add '@MainActor' to make static property 'defaultValue' part of global actor 'MainActor'
    |                `- note: disable concurrency-safety checks if accesses are protected by an external synchronization mechanism
141 |     @usableFromInline
142 |     struct Layout {
[15/15] Compiling LayoutUI ViewConstraints.swift
Build complete! (7.97s)
Build complete.
{
  "dependencies" : [
  ],
  "manifest_display_name" : "LayoutUI",
  "name" : "LayoutUI",
  "path" : "/Users/admin/builder/spi-builder-workspace",
  "platforms" : [
    {
      "name" : "ios",
      "version" : "13.0"
    },
    {
      "name" : "macos",
      "version" : "10.10"
    },
    {
      "name" : "watchos",
      "version" : "6.0"
    },
    {
      "name" : "tvos",
      "version" : "13.0"
    }
  ],
  "products" : [
    {
      "name" : "LayoutUI",
      "targets" : [
        "LayoutUI"
      ],
      "type" : {
        "library" : [
          "automatic"
        ]
      }
    }
  ],
  "targets" : [
    {
      "c99name" : "LayoutUITests",
      "module_type" : "SwiftTarget",
      "name" : "LayoutUITests",
      "path" : "Tests/LayoutUITests",
      "sources" : [
        "LayoutUITests.swift"
      ],
      "target_dependencies" : [
        "LayoutUI"
      ],
      "type" : "test"
    },
    {
      "c99name" : "LayoutUI",
      "module_type" : "SwiftTarget",
      "name" : "LayoutUI",
      "path" : "Sources/LayoutUI",
      "product_memberships" : [
        "LayoutUI"
      ],
      "sources" : [
        "LayoutBuilder.swift",
        "LayoutBuilders.swift",
        "RectAccessors.swift",
        "RectBasedLayout.swift",
        "RectConstraints.swift",
        "RectLayouts.swift",
        "StackLayout.swift",
        "StackLayouts.swift",
        "SwiftUI.swift",
        "UIKit+AppKit.swift",
        "ViewBasedLayout.swift",
        "ViewConstraints.swift"
      ],
      "type" : "library"
    }
  ],
  "tools_version" : "5.6"
}
Done.