Concurrency: Restore -enable-experimental-feature IsolatedAny.

Supported older compilers don't enable this feature by default, so it can't be
omitted from the `_Concurrency` module's flags (regression from
swiftlang#74543).

Additionally, remove `@_allowFeatureSuppression(IsolatedAny)` from all
declarations. We no longer need to support compilers that don't have the
`IsolatedAny` feature, so the suppression is superfluous and the alternative
branches didn't actually build anyways. _Additionally_, the suppressible
feature logic could not handle suppressing `IsolatedAny` simultaneously with
`SendingArgsAndResults`, resulting in a broken interface because `sending` was
used outside `#if $SendingArgsAndResults` guards.

Author: tshortli

stdlib/public/Concurrency/CMakeLists.txt

@@ -60,6 +60,12 @@ else()
   list(APPEND SWIFT_RUNTIME_CONCURRENCY_C_FLAGS "-fswift-async-fp=never")
 endif()
 
+# Do not remove until IsolatedAny is on by default in all supported compilers.
+list(APPEND SWIFT_RUNTIME_CONCURRENCY_SWIFT_FLAGS
+  "-enable-experimental-feature"
+  "IsolatedAny"
+)
+
 list(APPEND SWIFT_RUNTIME_CONCURRENCY_C_FLAGS
   "-D__STDC_WANT_LIB_EXT1__=1")
 

stdlib/public/Concurrency/DiscardingTaskGroup.swift

@@ -200,7 +200,6 @@ public struct DiscardingTaskGroup {
   ///     to set the child task's priority to the priority of the group.
   ///   - operation: The operation to execute as part of the task group.
   @_alwaysEmitIntoClient
-  @_allowFeatureSuppression(IsolatedAny)
   #if SWIFT_STDLIB_TASK_TO_THREAD_MODEL_CONCURRENCY
   @available(*, unavailable, message: "Unavailable in task-to-thread concurrency model", renamed: "addTask(operation:)")
   #endif
@@ -257,7 +256,6 @@ public struct DiscardingTaskGroup {
   /// - Returns: `true` if the child task was added to the group;
   ///   otherwise `false`.
   @_alwaysEmitIntoClient
-  @_allowFeatureSuppression(IsolatedAny)
   #if SWIFT_STDLIB_TASK_TO_THREAD_MODEL_CONCURRENCY
   @available(*, unavailable, message: "Unavailable in task-to-thread concurrency model", renamed: "addTask(operation:)")
   #endif
@@ -313,7 +311,6 @@ public struct DiscardingTaskGroup {
   }
 
   @_alwaysEmitIntoClient
-  @_allowFeatureSuppression(IsolatedAny)
   public mutating func addTask(
     operation: sending @escaping @isolated(any) () async -> Void
   ) {
@@ -357,7 +354,6 @@ public struct DiscardingTaskGroup {
 #if SWIFT_STDLIB_TASK_TO_THREAD_MODEL_CONCURRENCY
   @available(*, unavailable, message: "Unavailable in task-to-thread concurrency model", renamed: "addTaskUnlessCancelled(operation:)")
 #endif
-  @_allowFeatureSuppression(IsolatedAny)
   @_alwaysEmitIntoClient
   public mutating func addTaskUnlessCancelled(
     operation: sending @escaping @isolated(any) () async -> Void
@@ -892,7 +888,6 @@ public struct ThrowingDiscardingTaskGroup<Failure: Error> {
   @available(*, unavailable, message: "Unavailable in task-to-thread concurrency model", renamed: "addTask(operation:)")
 #endif
   @_alwaysEmitIntoClient
-  @_allowFeatureSuppression(IsolatedAny)
   public mutating func addTask(
     priority: TaskPriority? = nil,
     operation: sending @escaping @isolated(any) () async throws -> Void
@@ -936,7 +931,6 @@ public struct ThrowingDiscardingTaskGroup<Failure: Error> {
   @available(*, unavailable, message: "Unavailable in task-to-thread concurrency model", renamed: "addTask(operation:)")
 #endif
   @_alwaysEmitIntoClient
-  @_allowFeatureSuppression(IsolatedAny)
   public mutating func addTaskUnlessCancelled(
     priority: TaskPriority? = nil,
     operation: sending @escaping @isolated(any) () async throws -> Void

stdlib/public/Concurrency/Task.swift

@@ -608,7 +608,6 @@ extension Task where Failure == Never {
 #if SWIFT_STDLIB_TASK_TO_THREAD_MODEL_CONCURRENCY
   @discardableResult
   @_alwaysEmitIntoClient
-  @_allowFeatureSuppression(IsolatedAny)
   @available(*, unavailable, message: "Unavailable in task-to-thread concurrency model")
   public init(
     priority: TaskPriority? = nil,
@@ -665,7 +664,6 @@ extension Task where Failure == Never {
   ///   - operation: The operation to perform.
   @discardableResult
   @_alwaysEmitIntoClient
-  @_allowFeatureSuppression(IsolatedAny)
   public init(
     priority: TaskPriority? = nil,
     @_inheritActorContext @_implicitSelfCapture operation: sending @escaping @isolated(any) () async -> Success
@@ -704,7 +702,6 @@ extension Task where Failure == Error {
 #if SWIFT_STDLIB_TASK_TO_THREAD_MODEL_CONCURRENCY
   @discardableResult
   @_alwaysEmitIntoClient
-  @_allowFeatureSuppression(IsolatedAny)
   @available(*, unavailable, message: "Unavailable in task-to-thread concurrency model")
   public init(
     priority: TaskPriority? = nil,
@@ -761,7 +758,6 @@ extension Task where Failure == Error {
   ///   - operation: The operation to perform.
   @discardableResult
   @_alwaysEmitIntoClient
-  @_allowFeatureSuppression(IsolatedAny)
   public init(
     priority: TaskPriority? = nil,
     @_inheritActorContext @_implicitSelfCapture operation: sending @escaping @isolated(any) () async throws -> Success
@@ -802,7 +798,6 @@ extension Task where Failure == Never {
 #if SWIFT_STDLIB_TASK_TO_THREAD_MODEL_CONCURRENCY
   @discardableResult
   @_alwaysEmitIntoClient
-  @_allowFeatureSuppression(IsolatedAny)
   @available(*, unavailable, message: "Unavailable in task-to-thread concurrency model")
   public static func detached(
     priority: TaskPriority? = nil,
@@ -856,7 +851,6 @@ extension Task where Failure == Never {
   /// - Returns: A reference to the task.
   @discardableResult
   @_alwaysEmitIntoClient
-  @_allowFeatureSuppression(IsolatedAny)
   public static func detached(
     priority: TaskPriority? = nil,
     operation: sending @escaping @isolated(any) () async -> Success
@@ -895,7 +889,6 @@ extension Task where Failure == Error {
 #if SWIFT_STDLIB_TASK_TO_THREAD_MODEL_CONCURRENCY
   @discardableResult
   @_alwaysEmitIntoClient
-  @_allowFeatureSuppression(IsolatedAny)
   @available(*, unavailable, message: "Unavailable in task-to-thread concurrency model")
   public static func detached(
     priority: TaskPriority? = nil,
@@ -951,7 +944,6 @@ extension Task where Failure == Error {
   /// - Returns: A reference to the task.
   @discardableResult
   @_alwaysEmitIntoClient
-  @_allowFeatureSuppression(IsolatedAny)
   public static func detached(
     priority: TaskPriority? = nil,
     operation: sending @escaping @isolated(any) () async throws -> Success

stdlib/public/Concurrency/TaskGroup+TaskExecutor.swift

@@ -31,7 +31,6 @@ extension TaskGroup {
   ///     to set the child task's priority to the priority of the group.
   ///   - operation: The operation to execute as part of the task group.
   @_alwaysEmitIntoClient
-  @_allowFeatureSuppression(IsolatedAny)
   public mutating func addTask(
     executorPreference taskExecutor: (any TaskExecutor)?,
     priority: TaskPriority? = nil,
@@ -82,7 +81,6 @@ extension TaskGroup {
   /// - Returns: `true` if the child task was added to the group;
   ///   otherwise `false`.
   @_alwaysEmitIntoClient
-  @_allowFeatureSuppression(IsolatedAny)
   public mutating func addTaskUnlessCancelled(
     executorPreference taskExecutor: (any TaskExecutor)?,
     priority: TaskPriority? = nil,
@@ -146,7 +144,6 @@ extension ThrowingTaskGroup {
   ///     to set the child task's priority to the priority of the group.
   ///   - operation: The operation to execute as part of the task group.
   @_alwaysEmitIntoClient
-  @_allowFeatureSuppression(IsolatedAny)
   public mutating func addTask(
     executorPreference taskExecutor: (any TaskExecutor)?,
     priority: TaskPriority? = nil,
@@ -194,7 +191,6 @@ extension ThrowingTaskGroup {
   /// - Returns: `true` if the child task was added to the group;
   ///   otherwise `false`.
   @_alwaysEmitIntoClient
-  @_allowFeatureSuppression(IsolatedAny)
   public mutating func addTaskUnlessCancelled(
     executorPreference taskExecutor: (any TaskExecutor)?,
     priority: TaskPriority? = nil,
@@ -258,7 +254,6 @@ extension DiscardingTaskGroup {
   ///     to set the child task's priority to the priority of the group.
   ///   - operation: The operation to execute as part of the task group.
   @_alwaysEmitIntoClient
-  @_allowFeatureSuppression(IsolatedAny)
   public mutating func addTask(
     executorPreference taskExecutor: (any TaskExecutor)?,
     priority: TaskPriority? = nil,
@@ -311,7 +306,6 @@ extension DiscardingTaskGroup {
   /// - Returns: `true` if the child task was added to the group;
   ///   otherwise `false`.
   @_alwaysEmitIntoClient
-  @_allowFeatureSuppression(IsolatedAny)
   public mutating func addTaskUnlessCancelled(
     executorPreference taskExecutor: (any TaskExecutor)?,
     priority: TaskPriority? = nil,
@@ -375,7 +369,6 @@ extension ThrowingDiscardingTaskGroup {
   ///     to set the child task's priority to the priority of the group.
   ///   - operation: The operation to execute as part of the task group.
   @_alwaysEmitIntoClient
-  @_allowFeatureSuppression(IsolatedAny)
   public mutating func addTask(
     executorPreference taskExecutor: (any TaskExecutor)?,
     priority: TaskPriority? = nil,
@@ -428,7 +421,6 @@ extension ThrowingDiscardingTaskGroup {
   /// - Returns: `true` if the child task was added to the group;
   ///   otherwise `false`.
   @_alwaysEmitIntoClient
-  @_allowFeatureSuppression(IsolatedAny)
   public mutating func addTaskUnlessCancelled(
     executorPreference taskExecutor: (any TaskExecutor)?,
     priority: TaskPriority? = nil,

stdlib/public/Concurrency/TaskGroup.swift

@@ -326,7 +326,6 @@ public struct TaskGroup<ChildTaskResult: Sendable> {
   ///     to set the child task's priority to the priority of the group.
   ///   - operation: The operation to execute as part of the task group.
   @_alwaysEmitIntoClient
-  @_allowFeatureSuppression(IsolatedAny)
   public mutating func addTask(
     priority: TaskPriority? = nil,
     operation: sending @escaping @isolated(any) () async -> ChildTaskResult
@@ -373,7 +372,6 @@ public struct TaskGroup<ChildTaskResult: Sendable> {
   /// - Returns: `true` if the child task was added to the group;
   ///   otherwise `false`.
   @_alwaysEmitIntoClient
-  @_allowFeatureSuppression(IsolatedAny)
   public mutating func addTaskUnlessCancelled(
     priority: TaskPriority? = nil,
     operation: sending @escaping @isolated(any) () async -> ChildTaskResult
@@ -485,7 +483,6 @@ public struct TaskGroup<ChildTaskResult: Sendable> {
 #else // if SWIFT_STDLIB_TASK_TO_THREAD_MODEL_CONCURRENCY
   @available(SwiftStdlib 5.7, *)
   @available(*, unavailable, message: "Unavailable in task-to-thread concurrency model", renamed: "addTask(operation:)")
-  @_allowFeatureSuppression(IsolatedAny)
   public mutating func addTask(
     priority: TaskPriority? = nil,
     operation: sending @escaping @isolated(any) () async -> ChildTaskResult
@@ -498,7 +495,6 @@ public struct TaskGroup<ChildTaskResult: Sendable> {
   /// - Parameters:
   ///   - operation: The operation to execute as part of the task group.
   @_alwaysEmitIntoClient
-  @_allowFeatureSuppression(IsolatedAny)
   public mutating func addTask(
     operation: sending @escaping @isolated(any) () async -> ChildTaskResult
   ) {
@@ -541,7 +537,6 @@ public struct TaskGroup<ChildTaskResult: Sendable> {
   /// - Returns: `true` if the child task was added to the group;
   ///   otherwise `false`.
   @_alwaysEmitIntoClient
-  @_allowFeatureSuppression(IsolatedAny)
   public mutating func addTaskUnlessCancelled(
     operation: sending @escaping @isolated(any) () async -> ChildTaskResult
   ) -> Bool {
@@ -871,7 +866,6 @@ public struct ThrowingTaskGroup<ChildTaskResult: Sendable, Failure: Error> {
   ///     to set the child task's priority to the priority of the group.
   ///   - operation: The operation to execute as part of the task group.
   @_alwaysEmitIntoClient
-  @_allowFeatureSuppression(IsolatedAny)
   public mutating func addTask(
     priority: TaskPriority? = nil,
     operation: sending @escaping @isolated(any) () async throws -> ChildTaskResult
@@ -913,7 +907,6 @@ public struct ThrowingTaskGroup<ChildTaskResult: Sendable, Failure: Error> {
   /// - Returns: `true` if the child task was added to the group;
   ///   otherwise `false`.
   @_alwaysEmitIntoClient
-  @_allowFeatureSuppression(IsolatedAny)
   public mutating func addTaskUnlessCancelled(
     priority: TaskPriority? = nil,
     operation: sending @escaping @isolated(any) () async throws -> ChildTaskResult