Bump required toolchain to Swift 5.10

.github/workflows/pull_request.yml

@@ -9,7 +9,7 @@ jobs:
     name: Test
     uses: swiftlang/github-workflows/.github/workflows/swift_package_test.yml@main
     with:
-      linux_exclude_swift_versions: '[{"swift_version": "5.8"}]'
+      linux_exclude_swift_versions: '[{"swift_version": "5.8"}, {"swift_version": "5.9"}]'
       windows_exclude_swift_versions: '[{"swift_version": "5.9"}]'
 
   soundness:

CMakeLists.txt

@@ -1,7 +1,7 @@
 #[[
 This source file is part of the Swift Atomics Open Source Project
 
-Copyright (c) 2021 Apple Inc. and the Swift project authors
+Copyright (c) 2021 - 2025 Apple Inc. and the Swift project authors
 Licensed under Apache License v2.0 with Runtime Library Exception
 
 See https://swift.org/LICENSE.txt for license information
@@ -31,10 +31,7 @@ set(ATOMICS_C_FLAGS)
 if(CMAKE_Swift_COMPILER_VERSION VERSION_GREATER_EQUAL 5.9)
   list(APPEND ATOMICS_SWIFT_FLAGS
     "-enable-experimental-feature BuiltinModule"
-    "-DATOMICS_NATIVE_BUILTINS"
-    "-Xcc" "-DATOMICS_NATIVE_BUILTINS=1")
-  list(APPEND ATOMICS_C_FLAGS
-    "-DATOMICS_NATIVE_BUILTINS=1")
+    )
 endif()
 
 add_subdirectory(Sources)

Package.swift

@@ -1,9 +1,9 @@
-// swift-tools-version:5.9
+// swift-tools-version:5.10
 //===----------------------------------------------------------------------===//
 //
 // This source file is part of the Swift.org open source project
 //
-// Copyright (c) 2020 - 2023 Apple Inc. and the Swift project authors
+// Copyright (c) 2020 - 2025 Apple Inc. and the Swift project authors
 // Licensed under Apache License v2.0 with Runtime Library Exception
 //
 // See https://swift.org/LICENSE.txt for license information
@@ -18,10 +18,8 @@ var _swiftSettings: [SwiftSetting] = []
 
 // Enable the use of native Swift compiler builtins instead of C atomics.
 _cSettings += [
-  .define("ATOMICS_NATIVE_BUILTINS"),
 ]
 _swiftSettings += [
-  .define("ATOMICS_NATIVE_BUILTINS"),
   .enableExperimentalFeature("BuiltinModule")
 ]
 
@@ -48,7 +46,6 @@ let package = Package(
         "Conformances/IntegerConformances.swift.gyb",
         "Conformances/PointerConformances.swift.gyb",
         "Primitives/Primitives.native.swift.gyb",
-        "Primitives/Primitives.shims.swift.gyb",
         "Types/IntegerOperations.swift.gyb",
       ],
       cSettings: _cSettings,

Sources/Atomics/CMakeLists.txt

@@ -1,7 +1,7 @@
 #[[
 This source file is part of the Swift Atomics Open Source Project
 
-Copyright (c) 2021 - 2023 Apple Inc. and the Swift project authors
+Copyright (c) 2021 - 2025 Apple Inc. and the Swift project authors
 Licensed under Apache License v2.0 with Runtime Library Exception
 
 See https://swift.org/LICENSE.txt for license information
@@ -17,7 +17,6 @@ add_library(Atomics
   "Types/autogenerated/IntegerOperations.swift"
   "Unmanaged extensions.swift"
   "Primitives/autogenerated/Primitives.native.swift"
-  "Primitives/autogenerated/Primitives.shims.swift"
   "Conformances/RawRepresentable.swift"
   "Conformances/OptionalRawRepresentable.swift"
   "Conformances/autogenerated/IntegerConformances.swift"

Sources/Atomics/Conformances/AtomicBool.swift.gyb

@@ -2,7 +2,7 @@
 //
 // This source file is part of the Swift Atomics open source project
 //
-// Copyright (c) 2020 - 2023 Apple Inc. and the Swift project authors
+// Copyright (c) 2020 - 2025 Apple Inc. and the Swift project authors
 // Licensed under Apache License v2.0 with Runtime Library Exception
 //
 // See https://swift.org/LICENSE.txt for license information
@@ -16,7 +16,6 @@
 }%
 ${autogenerated_warning()}
 
-#if ATOMICS_NATIVE_BUILTINS
 import Builtin
 
 extension Bool {
@@ -26,9 +25,6 @@ extension Bool {
     self = unsafeBitCast(builtin, to: Bool.self)
   }
 }
-#else
-import _AtomicsShims
-#endif
 
 extension Bool: AtomicValue {
   @frozen
@@ -43,25 +39,16 @@ extension Bool: AtomicValue {
 
     @_transparent @_alwaysEmitIntoClient
     public init(_ value: Bool) {
-#if ATOMICS_NATIVE_BUILTINS
       _storage = value._atomicRepresentation
-#else
-      _storage = _sa_prepare_Int8(value._atomicRepresentation)
-#endif
     }
 
     @_transparent @_alwaysEmitIntoClient
     public func dispose() -> Value {
-#if ATOMICS_NATIVE_BUILTINS
       return _storage._decodeBool
-#else
-      return _sa_dispose_Int8(_storage)._decodeBool
-#endif
     }
   }
 }
 
-#if ATOMICS_NATIVE_BUILTINS
 extension Bool {
   @_transparent @_alwaysEmitIntoClient
   internal var _atomicRepresentation: _AtomicInt8Storage {
@@ -76,21 +63,6 @@ extension _AtomicInt8Storage {
     (Int8(self._value) & 1) != 0
   }
 }
-#else
-extension Bool {
-  @_transparent @_alwaysEmitIntoClient
-  internal var _atomicRepresentation: Int8 {
-    self ? 1 : 0
-  }
-}
-
-extension Int8 {
-  @_transparent @_alwaysEmitIntoClient
-  internal var _decodeBool: Bool {
-    (self & 1) != 0
-  }
-}
-#endif
 
 extension UnsafeMutablePointer
 where Pointee == Bool.AtomicRepresentation {