[stdlib] Make expected actor isolation checking crash by default

Only affects projects compiled with `-enable-actor-data-race-checks` flag.

Author: xedin

stdlib/public/Concurrency/Actor.cpp

@@ -353,7 +353,7 @@ static bool swift_task_isCurrentExecutorImpl(SerialExecutorRef executor) {
 /// 0 - no logging
 /// 1 - warn on each instance
 /// 2 - fatal error
-static unsigned unexpectedExecutorLogLevel = 1;
+static unsigned unexpectedExecutorLogLevel = 2;
 
 static void checkUnexpectedExecutorLogLevel(void *context) {
 #if SWIFT_STDLIB_HAS_ENVIRON

test/Concurrency/Runtime/data_race_detection.swift

@@ -1,5 +1,7 @@
-// RUN: %target-run-simple-swift( -Xfrontend -disable-availability-checking  -enable-actor-data-race-checks %import-libdispatch -parse-as-library) > %t.log 2>&1
-// RUN: %FileCheck %s < %t.log
+// RUN: %empty-directory(%t)
+// RUN: %target-build-swift %import-libdispatch -Xfrontend -disable-availability-checking -enable-actor-data-race-checks -parse-as-library -I %t %s -o %t/a.out -module-name main
+// RUN: %target-codesign %t/a.out
+// RUN: not --crash %target-run %t/a.out 2>&1 | %FileCheck %s
 
 // REQUIRES: executable_test
 // REQUIRES: concurrency
@@ -58,15 +60,10 @@ actor MyActor {
 @main
 struct Runner {
   static func main() async {
-    print("Launching a main-actor task")
-    // CHECK: warning: data race detected: @MainActor function at main/data_race_detection.swift:23 was not called on the main thread
-    launchFromMainThread()
-    sleep(1)
-
     let actor = MyActor()
     let actorFn = await actor.getTaskOnMyActor()
     print("Launching an actor-instance task")
-    // CHECK: warning: data race detected: actor-isolated function at main/data_race_detection.swift:52 was not called on the same actor
+    // CHECK: error: data race detected: actor-isolated function at main/data_race_detection.swift:57 was not called on the same actor
     launchTask(actorFn)
 
     sleep(1)

test/Concurrency/Runtime/data_race_detection_with_downgrade.swift

@@ -0,0 +1,82 @@
+// RUN: %empty-directory(%t)
+// RUN: %target-build-swift %import-libdispatch -Xfrontend -disable-availability-checking -enable-actor-data-race-checks -parse-as-library -I %t %s -o %t/a.out -module-name main
+// RUN: %target-codesign %t/a.out
+// RUN: env SWIFT_UNEXPECTED_EXECUTOR_LOG_LEVEL=1 %target-run %t/a.out 2>&1 | %FileCheck %s
+
+// Make sure that without downgrade the program crashes by default
+// RUN: not --crash %target-run %t/a.out 2>&1
+
+// REQUIRES: executable_test
+// REQUIRES: concurrency
+// REQUIRES: libdispatch
+
+// rdar://76038845
+// REQUIRES: concurrency_runtime
+// UNSUPPORTED: back_deployment_runtime
+// UNSUPPORTED: single_threaded_concurrency
+
+// Simulators don't pass `env` through to simulators even with `%env-`
+// REQUIRES: OS=macosx || OS=linux-gnu
+
+import _Concurrency
+import Dispatch
+
+// For sleep
+#if canImport(Darwin)
+import Darwin
+#elseif canImport(Glibc)
+import Glibc
+#endif
+
+@MainActor func onMainActor() {
+  print("I'm on the main actor!")
+}
+
+func promiseMainThread(_ fn: @escaping @MainActor () -> Void) -> (() -> Void) {
+  typealias Fn = () -> Void
+  return unsafeBitCast(fn, to: Fn.self)
+}
+
+func launchTask(_ fn: @escaping () -> Void) {
+  if #available(macOS 10.10, iOS 8.0, watchOS 2.0, tvOS 8.0, *) {
+    DispatchQueue.global().async {
+      fn()
+    }
+  }
+}
+
+func launchFromMainThread() {
+  launchTask(promiseMainThread(onMainActor))
+}
+
+actor MyActor {
+  var counter = 0
+
+  func onMyActor() {
+    counter = counter + 1
+  }
+
+  func getTaskOnMyActor() -> (() -> Void) {
+    return {
+      self.onMyActor()
+    }
+  }
+}
+
+@main
+struct Runner {
+  static func main() async {
+    print("Launching a main-actor task")
+    // CHECK: warning: data race detected: @MainActor function at main/data_race_detection.swift:28 was not called on the main thread
+    launchFromMainThread()
+    sleep(1)
+
+    let actor = MyActor()
+    let actorFn = await actor.getTaskOnMyActor()
+    print("Launching an actor-instance task")
+    // CHECK: warning: data race detected: actor-isolated function at main/data_race_detection.swift:57 was not called on the same actor
+    launchTask(actorFn)
+
+    sleep(1)
+  }
+}