temporarily disable Span and MutableSpan for Windows

The current Windows nightly is too old to be able to compile the expected syntax.

Author: glessard

Package.swift

@@ -135,6 +135,7 @@ let package = Package(
           swiftSettings: [
             .enableExperimentalFeature("VariadicGenerics"),
             .enableExperimentalFeature("LifetimeDependence"),
+            .enableExperimentalFeature("LifetimeDependenceMutableAccessors", .when(platforms: [.macOS, .linux])),
             .enableExperimentalFeature("AddressableTypes"),
             .enableExperimentalFeature("BuiltinModule"),
             .enableExperimentalFeature("AccessLevelOnImport")

Sources/FoundationEssentials/Data/Data.swift

@@ -2239,6 +2239,7 @@ public struct Data : Equatable, Hashable, RandomAccessCollection, MutableCollect
         }
     }
 
+#if $LifetimeDependenceMutableAccessors && !os(Windows)
     @available(FoundationSpan 6.2, *)
     public var mutableBytes: MutableRawSpan {
         @lifetime(&self)
@@ -2298,6 +2299,7 @@ public struct Data : Equatable, Hashable, RandomAccessCollection, MutableCollect
 #endif
         }
     }
+#endif // $LifetimeDependenceMutableAccessors && !os(Windows)
 
     @_alwaysEmitIntoClient
     public func withContiguousStorageIfAvailable<ResultType>(_ body: (_ buffer: UnsafeBufferPointer<UInt8>) throws -> ResultType) rethrows -> ResultType? {
@@ -2950,7 +2952,7 @@ extension Data : Codable {
 }
 
 // TODO: remove once _overrideLifetime is public in the standard library
-
+#if $LifetimeDependenceMutableAccessors && !os(Windows)
 /// Unsafely discard any lifetime dependency on the `dependent` argument. Return
 /// a value identical to `dependent` with a lifetime dependency on the caller's
 /// borrow scope of the `source` argument.
@@ -2964,8 +2966,6 @@ internal func _overrideLifetime<
 >(
   _ dependent: consuming T, borrowing source: borrowing U
 ) -> T {
-  // TODO: Remove @_unsafeNonescapableResult. Instead, the unsafe dependence
-  // should be expressed by a builtin that is hidden within the function body.
   dependent
 }
 
@@ -2982,8 +2982,6 @@ internal func _overrideLifetime<
 >(
   _ dependent: consuming T, copying source: borrowing U
 ) -> T {
-  // TODO: Remove @_unsafeNonescapableResult. Instead, the unsafe dependence
-  // should be expressed by a builtin that is hidden within the function body.
   dependent
 }
 
@@ -3001,7 +2999,6 @@ internal func _overrideLifetime<
   _ dependent: consuming T,
   mutating source: inout U
 ) -> T {
-  // TODO: Remove @_unsafeNonescapableResult. Instead, the unsafe dependence
-  // should be expressed by a builtin that is hidden within the function body.
   dependent
 }
+#endif

Tests/FoundationEssentialsTests/DataTests.swift

@@ -1634,6 +1634,7 @@ class DataTests : XCTestCase {
         // source.advanced(by: 5)
     }
 
+#if !os(Windows)
     func test_InlineDataSpan() throws {
         guard #available(FoundationSpan 6.2, *) else { throw XCTSkip("Span not available") }
 
@@ -1777,6 +1778,7 @@ class DataTests : XCTestCase {
         XCTAssertEqual(source[i], 0)
         XCTAssertEqual(source[i+1], .max)
     }
+#endif // !os(Windows)
 
     #if false // FIXME: XCTest doesn't support crash tests yet rdar://20195010&22387653
     func test_bounding_failure_subdata() {